Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
diff --git a/drivers/char/ftape/Kconfig b/drivers/char/ftape/Kconfig
new file mode 100644
index 0000000..7d3ecb5
--- /dev/null
+++ b/drivers/char/ftape/Kconfig
@@ -0,0 +1,340 @@
+#
+# Ftape configuration
+#
+config ZFTAPE
+	tristate "Zftape, the VFS interface"
+	depends on FTAPE
+	---help---
+	  Normally, you want to say Y or M. DON'T say N here or you
+	  WON'T BE ABLE TO USE YOUR FLOPPY TAPE DRIVE.
+
+	  The ftape module itself no longer contains the routines necessary
+	  to interface with the kernel VFS layer (i.e. to actually write data
+	  to and read data from the tape drive).  Instead the file system
+	  interface (i.e. the hardware independent part of the driver) has
+	  been moved to a separate module.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called zftape.
+
+	  Regardless of whether you say Y or M here, an additional runtime
+	  loadable module called `zft-compressor' which contains code to
+	  support user transparent on-the-fly compression based on Ross
+	  William's lzrw3 algorithm will be produced.  If you have enabled the
+	  kernel module loader (i.e. have said Y to "Kernel module loader
+	  support", above) then `zft-compressor' will be loaded
+	  automatically by zftape when needed.
+
+	  Despite its name, zftape does NOT use compression by default.  The
+	  file <file:Documentation/ftape.txt> contains a short description of
+	  the most important changes in the file system interface compared to
+	  previous versions of ftape.  The ftape home page
+	  <http://www.instmath.rwth-aachen.de/~heine/ftape/> contains
+	  further information.
+
+	  IMPORTANT NOTE: zftape can read archives created by previous
+	  versions of ftape and provide file mark support (i.e. fast skipping
+	  between tape archives) but previous version of ftape will lack file
+	  mark support when reading archives produced by zftape.
+
+config ZFT_DFLT_BLK_SZ
+	int "Default block size"
+	depends on ZFTAPE
+	default "10240"
+	---help---
+	  If unsure leave this at its default value, i.e. 10240. Note that
+	  you specify only the default block size here. The block size can be
+	  changed at run time using the MTSETBLK tape operation with the
+	  MTIOCTOP ioctl (i.e. with "mt -f /dev/qft0 setblk #BLKSZ" from the
+	  shell command line).
+
+	  The probably most striking difference between zftape and previous
+	  versions of ftape is the fact that all data must be written or read
+	  in multiples of a fixed block size. The block size defaults to
+	  10240 which is what GNU tar uses. The values for the block size
+	  should be either 1 or multiples of 1024 up to a maximum value of
+	  63488 (i.e. 62 K). If you specify `1' then zftape's builtin
+	  compression will be disabled.
+
+	  Reasonable values are `10240' (GNU tar's default block size),
+	  `5120' (afio's default block size), `32768' (default block size some
+	  backup programs assume for SCSI tape drives) or `1' (no restriction
+	  on block size, but disables builtin compression).
+
+comment "The compressor will be built as a module only!"
+	depends on FTAPE && ZFTAPE
+
+config ZFT_COMPRESSOR
+	tristate
+	depends on FTAPE!=n && ZFTAPE!=n
+	default m
+
+config FT_NR_BUFFERS
+	int "Number of ftape buffers (EXPERIMENTAL)"
+	depends on FTAPE && EXPERIMENTAL
+	default "3"
+	help
+	  Please leave this at `3' unless you REALLY know what you are doing.
+	  It is not necessary to change this value. Values below 3 make the
+	  proper use of ftape impossible, values greater than 3 are a waste of
+	  memory. You can change the amount of DMA memory used by ftape at
+	  runtime with "mt -f /dev/qft0 setdrvbuffer #NUMBUFFERS". Each buffer
+	  wastes 32 KB of memory. Please note that this memory cannot be
+	  swapped out.
+
+config FT_PROC_FS
+	bool "Enable procfs status report (+2kb)"
+	depends on FTAPE && PROC_FS
+	---help---
+	  Optional. Saying Y will result in creation of a directory
+	  `/proc/ftape' under the /proc file system. The files can be viewed
+	  with your favorite pager (i.e. use "more /proc/ftape/history" or
+	  "less /proc/ftape/history" or simply "cat /proc/ftape/history"). The
+	  file will contain some status information about the inserted
+	  cartridge, the kernel driver, your tape drive, the floppy disk
+	  controller and the error history for the most recent use of the
+	  kernel driver. Saying Y will enlarge the size of the ftape driver
+	  by approximately 2 KB.
+
+	  WARNING: When compiling ftape as a module (i.e. saying M to "Floppy
+	  tape drive") it is dangerous to use ftape's /proc file system
+	  interface. Accessing `/proc/ftape' while the module is unloaded will
+	  result in a kernel Oops. This cannot be fixed from inside ftape.
+
+choice
+	prompt "Debugging output"
+	depends on FTAPE
+	default FT_NORMAL_DEBUG
+
+config FT_NORMAL_DEBUG
+	bool "Normal"
+	---help---
+	  This option controls the amount of debugging output the ftape driver
+	  is ABLE to produce; it does not increase or diminish the debugging
+	  level itself. If unsure, leave this at its default setting,
+	  i.e. choose "Normal".
+
+	  Ftape can print lots of debugging messages to the system console
+	  resp. kernel log files. Reducing the amount of possible debugging
+	  output reduces the size of the kernel module by some KB, so it might
+	  be a good idea to use "None" for emergency boot floppies.
+
+	  If you want to save memory then the following strategy is
+	  recommended: leave this option at its default setting "Normal" until
+	  you know that the driver works as expected, afterwards reconfigure
+	  the kernel, this time specifying "Reduced" or "None" and recompile
+	  and install the kernel as usual. Note that choosing "Excessive"
+	  debugging output does not increase the amount of debugging output
+	  printed to the console but only makes it possible to produce
+	  "Excessive" debugging output.
+
+	  Please read <file:Documentation/ftape.txt> for a short description
+	  how to control the amount of debugging output.
+
+config FT_FULL_DEBUG
+	bool "Excessive"
+	help
+	  Extremely verbose output for driver debugging purposes.
+
+config FT_NO_TRACE
+	bool "Reduced"
+	help
+	  Reduced tape driver debugging output.
+
+config FT_NO_TRACE_AT_ALL
+	bool "None"
+	help
+	  Suppress all debugging output from the tape drive.
+
+endchoice
+
+comment "Hardware configuration"
+	depends on FTAPE
+
+choice
+	prompt "Floppy tape controllers"
+	depends on FTAPE
+	default FT_STD_FDC
+
+config FT_STD_FDC
+	bool "Standard"
+	---help---
+	  Only change this setting if you have a special controller. If you
+	  didn't plug any add-on card into your computer system but just
+	  plugged the floppy tape cable into the already existing floppy drive
+	  controller then you don't want to change the default setting,
+	  i.e. choose "Standard".
+
+	  Choose "MACH-2" if you have a Mountain Mach-2 controller.
+	  Choose "FC-10/FC-20" if you have a Colorado FC-10 or FC-20
+	  controller.
+	  Choose "Alt/82078" if you have another controller that is located at
+	  an IO base address different from the standard floppy drive
+	  controller's base address of `0x3f0', or uses an IRQ (interrupt)
+	  channel different from `6', or a DMA channel different from
+	  `2'. This is necessary for any controller card that is based on
+	  Intel's 82078 FDC such as Seagate's, Exabyte's and Iomega's "high
+	  speed" controllers.
+
+	  If you choose something other than "Standard" then please make
+	  sure that the settings for the IO base address and the IRQ and DMA
+	  channel in the configuration menus below are correct. Use the manual
+	  of your tape drive to determine the correct settings!
+
+	  If you are already successfully using your tape drive with another
+	  operating system then you definitely should use the same settings
+	  for the IO base, the IRQ and DMA channel that have proven to work
+	  with that other OS.
+
+	  Note that this menu lets you specify only the default setting for
+	  the hardware setup. The hardware configuration can be changed at
+	  boot time (when ftape is compiled into the kernel, i.e. if you
+	  have said Y to "Floppy tape drive") or module load time (i.e. if you
+	  have said M to "Floppy tape drive").
+
+	  Please read also the file <file:Documentation/ftape.txt> which
+	  contains a short description of the parameters that can be set at
+	  boot or load time. If you want to use your floppy tape drive on a
+	  PCI-bus based system, please read the file
+	  <file:drivers/char/ftape/README.PCI>.
+
+config FT_MACH2
+	bool "MACH-2"
+
+config FT_PROBE_FC10
+	bool "FC-10/FC-20"
+
+config FT_ALT_FDC
+	bool "Alt/82078"
+
+endchoice
+
+comment "Consult the manuals of your tape drive for the correct settings!"
+	depends on FTAPE && !FT_STD_FDC
+
+config FT_FDC_BASE
+	hex "IO base of the floppy disk controller"
+	depends on FTAPE && !FT_STD_FDC
+	default "0"
+	---help---
+	  You don't need to specify a value if the following default
+	  settings for the base IO address are correct:
+	  <<< MACH-2     : 0x1E0 >>>
+	  <<< FC-10/FC-20: 0x180 >>>
+	  <<< Secondary  : 0x370 >>>
+	  Secondary refers to a secondary FDC controller like the "high speed"
+	  controllers delivered by Seagate or Exabyte or Iomega's Ditto Dash.
+	  Please make sure that the setting for the IO base address
+	  specified here is correct. USE THE MANUAL OF YOUR TAPE DRIVE OR
+	  CONTROLLER CARD TO DETERMINE THE CORRECT SETTING. If you are already
+	  successfully using the tape drive with another operating system then
+	  you definitely should use the same settings for the IO base that has
+	  proven to work with that other OS.
+
+	  Note that this menu lets you specify only the default setting for
+	  the IO base. The hardware configuration can be changed at boot time
+	  (when ftape is compiled into the kernel, i.e. if you specified Y to
+	  "Floppy tape drive") or module load time (i.e. if you have said M to
+	  "Floppy tape drive").
+
+	  Please read also the file <file:Documentation/ftape.txt> which
+	  contains a short description of the parameters that can be set at
+	  boot or load time.
+
+config FT_FDC_IRQ
+	int "IRQ channel of the floppy disk controller"
+	depends on FTAPE && !FT_STD_FDC
+	default "0"
+	---help---
+	  You don't need to specify a value if the following default
+	  settings for the interrupt channel are correct:
+	  <<< MACH-2     : 6 >>>
+	  <<< FC-10/FC-20: 9 >>>
+	  <<< Secondary  : 6 >>>
+	  Secondary refers to secondary a FDC controller like the "high speed"
+	  controllers delivered by Seagate or Exabyte or Iomega's Ditto Dash.
+	  Please make sure that the setting for the IO base address
+	  specified here is correct. USE THE MANUAL OF YOUR TAPE DRIVE OR
+	  CONTROLLER CARD TO DETERMINE THE CORRECT SETTING. If you are already
+	  successfully using the tape drive with another operating system then
+	  you definitely should use the same settings for the IO base that has
+	  proven to work with that other OS.
+
+	  Note that this menu lets you specify only the default setting for
+	  the IRQ channel. The hardware configuration can be changed at boot
+	  time (when ftape is compiled into the kernel, i.e. if you said Y to
+	  "Floppy tape drive") or module load time (i.e. if you said M to
+	  "Floppy tape drive").
+
+	  Please read also the file <file:Documentation/ftape.txt> which
+	  contains a short description of the parameters that can be set at
+	  boot or load time.
+
+config FT_FDC_DMA
+	int "DMA channel of the floppy disk controller"
+	depends on FTAPE && !FT_STD_FDC
+	default "0"
+	---help---
+	  You don't need to specify a value if the following default
+	  settings for the DMA channel are correct:
+	  <<< MACH-2     : 2 >>>
+	  <<< FC-10/FC-20: 3 >>>
+	  <<< Secondary  : 2 >>>
+	  Secondary refers to a secondary FDC controller like the "high speed"
+	  controllers delivered by Seagate or Exabyte or Iomega's Ditto Dash.
+	  Please make sure that the setting for the IO base address
+	  specified here is correct. USE THE MANUAL OF YOUR TAPE DRIVE OR
+	  CONTROLLER CARD TO DETERMINE THE CORRECT SETTING. If you are already
+	  successfully using the tape drive with another operating system then
+	  you definitely should use the same settings for the IO base that has
+	  proven to work with that other OS.
+
+	  Note that this menu lets you specify only the default setting for
+	  the DMA channel. The hardware configuration can be changed at boot
+	  time (when ftape is compiled into the kernel, i.e. if you said Y to
+	  "Floppy tape drive") or module load time (i.e. if you said M to
+	  "Floppy tape drive").
+
+	  Please read also the file <file:Documentation/ftape.txt> which
+	  contains a short description of the parameters that can be set at
+	  boot or load time.
+
+config FT_FDC_THR
+	int "Default FIFO threshold (EXPERIMENTAL)"
+	depends on FTAPE && EXPERIMENTAL
+	default "8"
+	help
+	  Set the FIFO threshold of the FDC. If this is higher the DMA
+	  controller may serve the FDC after a higher latency time. If this is
+	  lower, fewer DMA transfers occur leading to less bus contention.
+	  You may try to tune this if ftape annoys you with "reduced data
+	  rate because of excessive overrun errors" messages. However, this
+	  doesn't seem to have too much effect.
+
+	  If unsure, don't touch the initial value, i.e. leave it at "8".
+
+config FT_FDC_MAX_RATE
+	int "Maximal data rate to use (EXPERIMENTAL)"
+	depends on FTAPE && EXPERIMENTAL
+	default "2000"
+	---help---
+	  With some motherboard/FDC combinations ftape will not be able to
+	  run your FDC/tape drive combination at the highest available
+	  speed. If this is the case you'll encounter "reduced data rate
+	  because of excessive overrun errors" messages and lots of retries
+	  before ftape finally decides to reduce the data rate.
+
+	  In this case it might be desirable to tell ftape beforehand that
+	  it need not try to run the tape drive at the highest available
+	  speed. If unsure, leave this disabled, i.e. leave it at 2000
+	  bits/sec.
+
+config FT_ALPHA_CLOCK
+	int "CPU clock frequency of your DEC Alpha" if ALPHA
+	depends on FTAPE
+	default "0"
+	help
+	  On some DEC Alpha machines the CPU clock frequency cannot be
+	  determined automatically, so you need to specify it here ONLY if
+	  running a DEC Alpha, otherwise this setting has no effect.
+
diff --git a/drivers/char/ftape/Makefile b/drivers/char/ftape/Makefile
new file mode 100644
index 0000000..0e67d2f
--- /dev/null
+++ b/drivers/char/ftape/Makefile
@@ -0,0 +1,28 @@
+#
+#       Copyright (C) 1997 Claus Heine.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; see the file COPYING.  If not, write to
+# the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+#
+# $Source: /homes/cvs/ftape-stacked/ftape/Makefile,v $
+# $Revision: 1.4 $
+# $Date: 1997/10/05 19:17:56 $
+#
+#      Makefile for the QIC-40/80/3010/3020 floppy-tape driver for
+#      Linux.
+#
+
+obj-$(CONFIG_FTAPE)		+= lowlevel/
+obj-$(CONFIG_ZFTAPE)		+= zftape/
+obj-$(CONFIG_ZFT_COMPRESSOR)	+= compressor/
diff --git a/drivers/char/ftape/README.PCI b/drivers/char/ftape/README.PCI
new file mode 100644
index 0000000..18de159
--- /dev/null
+++ b/drivers/char/ftape/README.PCI
@@ -0,0 +1,81 @@
+Some notes for ftape users with PCI motherboards:
+=================================================
+
+The problem:
+------------
+
+There have been some problem reports from people using PCI-bus based
+systems getting overrun errors.
+I wasn't able to reproduce these until I ran ftape on a Intel Plato
+(Premiere PCI II) motherboard with bios version 1.00.08AX1.
+It turned out that if GAT (Guaranteed Access Timing) is enabled (?)
+ftape gets a lot of overrun errors.
+The problem disappears when disabling GAT in the bios.
+Note that Intel removed this setting (permanently disabled) from the
+1.00.10AX1 bios !
+
+It looks like that if GAT is enabled there are often large periods
+(greater than 120 us !??) on the ISA bus that the DMA controller cannot
+service the floppy disk controller.
+I cannot imagine this being acceptable in a decent PCI implementation.
+Maybe this is a `feature' of the chipset. I can only speculate why
+Intel choose to remove the option from the latest Bios...
+
+The lesson of this all is that there may be other motherboard
+implementations having the same of similar problems.
+If you experience a lot of overrun errors during a backup to tape,
+see if there is some setting in the Bios that may influence the
+bus timing.
+
+I judge this a hardware problem and not a limitation of ftape ;-)
+My DOS backup software seems to be suffering from the same problems
+and even refuses to run at 1 Mbps !
+Ftape will reduce the data-rate from 1 Mbps to 500 Kbps if the number
+of overrun errors on a track exceeds a threshold.
+
+
+Possible solutions:
+-------------------
+
+Some of the problems were solved by upgrading the (flash) bios.
+Other suggest that it has to do with the FDC being on the PCI
+bus, but that is not the case with the Intel Premiere II boards.
+[If upgrading the bios doesn't solve the problem you could try
+a floppy disk controller on the isa-bus].
+
+Here is a list of systems and recommended BIOS settings:
+
+
+        Intel Premiere PCI (Revenge):
+
+Bios version 1.00.09.AF2 is reported to work.
+
+
+
+        Intel Premiere PCI II (Plato):
+
+Bios version 1.00.10.AX1 and version 11 beta are ok.
+If using version 1.00.08.AX1, GAT must be disabled !
+
+
+
+        ASUS PCI/I-SP3G:
+
+Preferred settings:     ISA-GAT-mode : disabled
+                        DMA-linebuffer-mode : standard
+                        ISA-masterbuffer-mode : standard
+
+
+        DELL Dimension XPS P90
+
+Bios version A2 is reported to be broken, while bios version A5 works.
+You can get a flash bios upgrade from http://www.dell.com
+
+
+To see if you're having the GAT problem, try making a backup
+under DOS. If it's very slow and often repositions you're
+probably having this problem.
+
+                        --//--
+ LocalWords:  ftape PCI bios GAT ISA DMA chipset Mbps Kbps FDC isa AF ok ASUS
+ LocalWords:  SP linebuffer masterbuffer XPS http www com
diff --git a/drivers/char/ftape/RELEASE-NOTES b/drivers/char/ftape/RELEASE-NOTES
new file mode 100644
index 0000000..03799db
--- /dev/null
+++ b/drivers/char/ftape/RELEASE-NOTES
@@ -0,0 +1,966 @@
+Hey, Emacs, we're -*-Text-*- mode!
+
+===== Release notes for ftape-3.04d 25/11/97 =====
+- The correct pre-processor statement for "else if" is "#elif" not
+  "elsif".
+- Need to call zft_reset_position() when overwriting cartridges
+  previously written with ftape-2.x, sftape, or ancient
+  (pre-ftape-3.x) versions of zftape.
+
+===== Release notes for ftape-3.04c 16/11/97 =====
+- fdc_probe() was calling DUMPREGS with a result length of "1" which
+  was just fine. Undo previous change.
+
+===== Release notes for ftape-3.04b 14/11/97 =====
+
+- patches/2.x.x/floppy.c.diff was somewhat broken, releasing i/o
+  regions it never had allocated.
+- fdc_probe() was calling DUMPREGS with a result length of "1" instead
+  of "10"
+- Writing deleted data marks if the first segents on track zero are
+  should work now.
+- ftformat should now be able to handle those cases where the tape
+  drive sets the read only status bit (QIC-40/80 cartridges with
+  QIC-3010/3020 tape drives) because the header segment is damaged.
+- the MTIOCFTCMD ioctl may now be issued by the superuser ONLY.
+
+===== Release notes for ftape-3.04a 12/11/97 =====
+- Fix an "infinite loop can't be killed by signal" bug in
+  ftape_get_drive_status(). Only relevant when trying to access
+  buggy/misconfigured hardware
+- Try to compensate a bug in the HP Colorado T3000's firmware: it
+  doesn't set the write protect bit for QIC80/QIC40 cartridges.
+
+===== Release notes for ftape-3.04 06/11/97 =====
+- If positioning with fast seeking fails fall back to a slow seek
+  before giving up.
+- (nearly) no retries on "no data errors" when verifying after
+  formatting. Improved tuning of the bad sector map after formatting.
+- the directory layout has changed again to allow for easier kernel
+  integration
+- Module parameter "ftape_tracing" now is called "ft_tracing" because
+  the "ftape_tracing" variable has the version checksum attached to it.
+- `/proc/ftape' interface for 2.0.* kernels. `/proc/ftape' no longer
+  is a directory but a file that contains all the information formerly
+  provided in separate files under the `/proc/ftape/' directory.
+- Most of the configuration options have been prefixed by "CONFIG_FT_"
+  in preparation of the kernel inclusion. The Makefiles under
+  "./ftape/" should be directly usable by the kernel.
+- The MODVERSIONS stuff is now auto-detected.
+- Broke backslashed multi line options in MCONFIG into separate lines
+  using GNU-make's "+=" feature.
+- The html and dvi version of the manual is now installed under
+  '/usr/doc/ftape` with 'make install`
+- New SMP define in MCONFIG. ftape works with SMP if this is defined.
+- attempt to cope with "excessive overrun errors" by gradually
+  increasing FDC FIFO threshold. But this doesn't seem to have too
+  much an effect.
+- New load time configuration parameter "ft_fdc_rate_limit". If you
+  encounter too many overrun errors with a 2Mb controller then you
+  might want to set this to 1000.
+- overrun errors on the last sector in a segment sometimes result in
+  a zero DMA residue. Dunno why, but compensate for it.
+- there were still fdc_read() timeout errors. I think I have fixed it
+  now, please FIXME.
+- Sometimes ftape_write() failed to re-start the tape drive when a
+  segment without a good sector was reached ("wait for empty segment
+  failed"). This is fixed. Especially important for > QIC-3010.
+- sftape (aka ftape-2.x) has vanished. I didn't work on it for
+  ages. It is probably still possible to use the old code with
+  ftape-3.04, if one really needs it (BUT RECOMPILE IT)
+- zftape no longer alters the contents of already existing volume
+  table entries, which makes it possible to fill in missing fields,
+  like time stamps using some user space program.
+- ./contrib/vtblc/ contains such a program.
+- new perl script ./contrib/scripts/listtape that list the contents of a
+  floppy tape cartridge parsing the output of "mt volinfo" + "mt fsf"
+- the MTWEOF implementation has changed a little bit (after I had a
+  look at amanda). Calling MTWEOF while the tape is still held open
+  after writing something to the tape now will terminate the current
+  volume, and start a new one at the current position.
+- the volume table maintained by zftape now is a doubly linked list
+  that grows dynamically as needed.
+
+  formatting floppy tape cartridges
+  ---------------------------------
+  * there is a new user space formatting program that does most of the
+    dirty work in user space (auto-detect, computing the sector
+    coordinates, adjusting time stamps and statistics). It has a
+    simple command line interface.
+  * ftape-format.o has vanished, it has been folded into the low level
+    ftape.o module, and the ioctl interface into zftape.o. Most of the
+    complicated stuff has been moved to user space, so there was no
+    need for a separate module anymore.
+  * there is a new ioctl MTIOCFTCMD that sends a bare QIC-117 command
+    to the tape drive.
+  * there is a new mmap() feature to map the dma buffers into user
+    space to be used by the user level formatting program.
+  * Formatting of yet unformatted or totally degaussed cartridges
+    should be possible now. FIXME.
+
+===== Release notes for ftape-3.03b, <forgot the exact date> ====
+
+ftape-3.03b was released as a beta release only. Its main new feature
+was support of the DITTO-2GB drive. This was made possible by reverse
+engineering done by <fill in his name> after Iomega failed to support
+ftape. Although they had promised to do so (this makes me feel a bit
+sad and uncomfortable about Iomega).
+
+===== Release notes for ftape-3.03a, 22/05/97 ====
+
+- Finally fixed auto-un-loading of modules for kernels > 2.1.18
+- Add an "uninstall" target to the Makefile
+- removed the kdtime hack
+- texi2www didn't properly set the back-reference from a footnote back
+  to the regular text.
+
+  zftape specific
+  ---------------
+  * hide the old compression map volume. Taper doesn't accept the
+    presence of non-Taper volumes and Taper-written volume on the same
+    tape.
+  * EOD (End Of Data) handling was still broken: the expected behavior
+    is to return a zero byte count at the first attempt to read past
+    EOD, return a zero byte count at the second attempt to read past
+    EOD and THEN return -EIO.
+  
+  ftape-format specific
+  ---------------------
+  * Detection of QIC-40 cartridges in select_tape_format() was broken
+    and made it impossible to format QIC-3010/3020 cartridges.
+  * There are strange "TR-1 Extra" cartridges out there which weren't
+    detected properly because the don't strictly conform to the
+    QIC-80, Rev. N, spec.
+
+===== Release notes for ftape-3.03, 30/04/97 =====
+
+- Removed kernel integration code from the package. I plan to provide
+  a package that can be integrated into the stock kernel separately
+  (hopefully soon).
+  As a result, a simple `make' command now will build everything.
+- ALL compile time configuration options have been moved to the file
+  `MCONFIG'.
+- Quite a few `low level' changes to allow formatting of cartridges.
+- formatting is implemented as a separate module `ftape-format.o'. The
+  modified `mt' program contains sample code that shows how to use it.
+- The VFS interface has been moved from the `ftape.o' module to the
+  high level modules `zftape.o' resp. `sftape.o'. `ftape.o' contains
+  the hardware support only.
+- A bit of /proc support for kernels > 2.1.28
+- Moved documentation to Doc subdir. INSTALL now contains some real
+  installation notes.
+- `install' target in Makefile.
+
+zftape specific:
+----------------
+
+- zftape works for large cartridges now ( > 2^31 bytes)
+- MTIOCVOLINFO and MTIOCGETSIZE now return the size in KILOBYTES,
+  NO LONGER in bytes.
+
+- permissions for write access to a cartridge have changed:
+  * zftape now also takes the file access mode into account
+  * zftape no longer allows writing in the middle of the recorded
+    media. The tape has to be positioned at BOT or EOD for write
+    access.
+
+- MTBSF has changed. It used to position at the beginning of the
+  previous file when called with count 1. This was different from the
+  expected behavior for other Un*x tape drivers (i.e. SCSI). MTBSF
+  with count 1 should merely position at the beginning of the current
+  volume. Fixed. As a result, `tar --verify' now produces the desired
+  result: it verifies the last written volume, not the pre-last
+  written volume.
+
+- The compression map has vanished --> no need for `mt erase' any
+  more. Fast seeking in a compressed volume is still be possible, but
+  takes slightly longer. As a side effect, you may experience an
+  additional volume showing up in front of all others for old
+  cartridges. This is the tape volume that holds the compression map.
+
+- The compression support for zftape has been moved to a separate
+  module `zft-compressor'. DON'T forget to load it before trying to
+  read back compressed volumes. The stock `zftape.o' module probes for
+  the module `zft-compressor' using the kerneld message channel; you
+  have to install `zft-compressor.o' in a place where modprobe can
+  find it if you want to use this.
+
+- New experimental feature that tries to get the broken down GMT time
+  from user space via a kernel daemon message channel. You need to
+  compile and start the `kdtime' daemon contained in the contrib
+  directory to use it. Needed (?) for time stamps in the header
+  segments and the volume table.
+
+- variable block size mode via MTSETBLK 0
+
+- keep modules locked in memory after the block size has been changed
+
+sftape specific:
+----------------
+
+- end of tape handling should be fixed, i.e. multi volume archives
+  written with `afio' can be read back now.
+
+
+===== Release notes for ftape-3.02a, 09/01/97 =====
+
+No big news:
+- call zft_init() resp. sft_init() when compiling the entire stuff
+  into the kernel image.
+- fix bug in ftape-setup.c when NO_TRACE_AT_ALL was defined.
+- fix bug in sftape-eof.c/zftape-eof.c for old kernels (1.2.*)
+- add support for new module interface for recent kernels
+
+===== Release notes for ftape-3.02, 16/12/96 =====
+- Fixed the `FDC unlock command failed' bug in fdc-io.c. When the FIFO
+  was already locked when ftape was loaded, ftape failed to unlock it.
+- Fixed compilation of `contrib/gnumt'. It now finds `mtio.h' even if
+  ftape is NOT included into the kernel source tree.
+- fc-10.c: include <asm/io.h> for inb() and outb().
+- ftape/sftape/zftape: all global variable now have either a `ftape_',
+  a `ft_', `sft_', `zft_' or `qic_' prefix to prevent name clashes
+  with other parts of the kernel when including ftape into the kernel
+  source tree.
+- Kerneld support has changed. `ftape' now searches for a module
+  `ftape-frontend' when none of the frontend (`sftape' or `zftape') is
+  loaded. Please refer to the `Installation/Loading ftape' section of
+  the TeXinfo manual.
+- Add load resp. boot-time configuration of ftape. There are now
+  variables ft_fdc_base, ft_fdc_dma and ft_fdc_irq corresponding to
+  the former FDC_BASE etc. compile time definitions. One can also use
+  the kernel command line parameters to configure the driver if it is
+  compiled into the kernel. Also, the FC-10/FC-20 support is load-time
+  configurable now as well as the MACH-II hack (ft_probe_fc10,
+  resp. ft_mach2). Please refer to the section `Installation/Configure
+  ftape' of the TeXinfo manual.
+- I removed the MODVERSIONS option from `Makefile.module'. Let me alone
+  with ftape and MODVERSIONS unless you include the ftape sources into
+  the kernel source tree.
+- new vendors in `vendors.h':
+  * HP Colorado T3000 
+  * ComByte DoublePlay (including a bug fix for their broken
+    formatting software, thanks to whraven@njackn.com)
+  * Iomega DITTO 2GIG. NOTE: this drive cannot work with ftape because
+    the logical data layout of the cartridges used by this drive does
+    NOT conform to the QIC standards, it is a special Iomega specific
+    format. I've sent mail to Iomega but didn't receive an answer
+    yet. If you want this drive to be supported by ftape, ask Iomega
+    to give me information about it.
+- zftape:
+  * re-introduced the MTIOC_ZFTAPE_GETBLKSZ ioctl for compatibility
+    with zftape 1.06a and earlier. Please don't use it when writing
+    new software, use the MTIOCVOLINFO ioctl instead.
+  * Major overhaul of the code that updates the header segments. Never
+    change the tape label unless erasing the tape. Thus we almost
+    never need to write the header segments, unless we would modify
+    the bad sector map which isn't done yet. Updating of volume table
+    and compression map more secure now although it takes a bit
+    longer.
+  * Fixed bug when aborting a write operation with a signal: zftape
+    now finishes the current volume (i.e. writes an eof marker) at the
+    current position. It didn't before which led to somehow *strange*
+    behavior in this cases.
+  * Keep module locked in memory when using it with  the non-rewinding
+    devices and the tape is not logical at BOT. Needed for kerneld
+    support.
+- sftape:
+  * Keep module locked in memory when using it with  the non-rewinding
+    devices and the tape is not logical at BOT. Needed for kerneld
+    support.
+
+===== Release notes for ftape-3.01, 14/11/96 =====
+
+- Fixed silly bugs in ftape-3.00:
+  * MAKEDEV.ftape: major device number must be 27, not 23 
+  * sftape/sftape-read.c: sftape_read_header_segments() called 
+    itself recursively instead of calling ftape_read_header_segment()
+  * zftape/qic-vtbl.h: conversion of ftape's file marks to zftape's
+    internal volume table was broken.
+  * patches/2.x.x/linux-2.0.21.dif: my RCS (resp. CVS) system replaced
+    the `$Revison:' etc. macros in the `ftape.h' concerning part of the
+    patch :-( Fixed.
+  * info/ftape.info: Fixed misspellings (`cp' <-> `cp -r' etc.)
+  * when ftape/sftape or ftape/zftape was compiled into the kernel the
+    variable ftape_status was declared twice. Fixed.
+  * removed reference to undeclared variable kernel_version when not
+    compiling as module
+  * fixed a bug introduced by the use of bit-fields for some flags
+    (i.e. write_protected, no_cartridge, formatted)
+  * flag `header_read' is now reset correctly to zero when tape is
+    removed.
+- fixed a bug in sftape/sftape-eof.c that was already in the original
+  ftape code. MTFSF/BSF was not handled correctly when positioned
+  right before the file mark (think of tar)
+- Changed TRACE macros (following a suggestion of Marcin Dalecki) to use
+  the predefined __FUNCTION__ macro of GCC. Spares about 4k of code.
+- added new vendor id for Iomega DITTO 2GIG
+- fixed a bug already present in zftape-1.06 when aborting a write
+  with a signal: we now finish the current volume at that
+  position. Header segments remain NOT up to date until an explicit call
+  to MTREW or MTOFFL is done.  
+
+===== Release notes for ftape-3.00, 14/10/96 =====
+
+- Merged ftape with zftape. There are three modules now:
+  ftape for the hardware support, sftape for the implementation of the
+  original ftape eof mark stuff and zftape that implements zftape's way
+  of handling things (compression, volume table, tape blocks of
+  constant length)
+- Documentation in TeXinfo format in the `info' subdirectory.
+- New ioctls for zftape. See zftape/zftape.h
+- Dummy formatting ioctl for ftape. See ftape.h
+- Kernel patch files for the 2.*.* series to include ftape-3.00 in the
+  kernel source tree. These includes a kernel compatible Config.in
+  script and fairly large online information for the kernel configure
+  script.
+- Support for compiling with Linux-1.2.13. 
+- Modified GNU mt from their cpio package that can handle the new
+  ioctls.
+- ftape/sftape/zftape is kerneld save now!
+
+Notes on sftape:
+- sftape implements the eof handling code of the original ftape. If
+  you like to stick with the original ftape stuff, you have to use
+  this module, not zftape.
+- sftape is kerneld save, unlike the original ftape.
+- we keep the entire header segment now in memory, so no need to read
+  it before updating the header segments. Additional memory
+  consumption: 256 bytes. 
+
+Notes for zftape:
+- zftape has support for tapes with format code 6 now, which use a
+  slightly different volume table format compared with other floppy
+  tapes.
+- new ioctls for zftape. Have a look at zftape/zftape.h
+- The internal volume table representation has changed for zftape. Old
+  cartridges are converted automatically.
+- zftape no longer uses compression map segments, which have vanished
+  from the QIC specs, but creates volume table entry that reserves
+  enough space for the compression map. 
+- zftape is kerneld save now.
+- we keep the entire header segment now in memory, so no need to read
+  it before updating the header segments. Additional memory
+  consumption: 256 bytes. 
+
+Notes for contrib/gnumt:
+- modified mt from the GNU cpio package that supports all the new
+  ioctls of zftape.
+Notes for contrib/swapout:
+- This contains the swapout.c program that was written by Kai
+  Harrekilde-Pederson. I simply added a Makefile.
+
+===== Release notes for ftape-2.10, 14/10/96 =====
+
+The ftape maintainer has changed. 
+Kai Harrekilde-Petersen <khp@dolphinics.no>
+has resigned from maintaining ftape, and I,
+Claus-Justus Heine <claus@momo.math.rwth-aachen.de>,
+have taken over.
+
+- Added support for tapes with `format code 6', i.e. QIC-3020 tapes
+  with more than 2^16 segments.
+- merged changes made by Bas Laarhoven with ftape-2.09. Refer
+  to his release notes below. I've included them into this
+  file unchanged for your reference.
+- disabled call stack back trace for now. This new feature
+  introduced by the interim release 2.0.x still seems to
+  be buggy.
+- Tried to minimize differences between the ftape version
+  to be included into the kernel source tree and the standalone
+  module version.
+- Reintroduced support for Linux-1.2.13. Please refer to the
+  Install-guide. 
+
+===== Release notes for ftape-2.09, 16/06/96 =====
+
+There aren't any really big news in this release, mostly just that I
+(the maintainer) have changed my email address (due to a new job).  My
+new address is <khp@dolphinics.no>
+
+- The CLK_48MHZ and FDC_82078SL options has gone (all 2Mbps cards seem
+  to use a 48MHz oscillator anyway and I haven't heard of an 'SL
+  chip out there).
+- The S82078B has been `downgraded' to i82077AA compability.
+- TESTING option revived.  Right now, it'll enable the (seriously broken)
+  2Mbps code.  If you enable it, you'll experience a tape drive that's
+  *really* out to lunch!
+- Some (bold) changes in the init code.  Please notify me if they
+  break things for you.
+
+===== Release notes for ftape-2.08, 14/03/96 =====
+
+If you correct a problem with ftape, please send your patch to
+khp@dolphinics.no too.
+
+- Updated to reflect that NR_MEM_LISTS is gone in 1.3.74
+- Teac 700 added to list of known drives.
+- The registered device name is now "ft" rather than "ftape".
+
+===== Release notes for ftape-2.07a, 14/03/96 =====
+
+Bugfixes by Marcin Dalecki <dalecki@namu03.gwdg.de>:
+- In the last release it just compiled against 1.3.70;
+  now the params to request_irq() and free_irq are() are fixed, so it also 
+  works in 1.3.73 :-)
+- Support for modules is now correct for newer kernels.
+
+===== Release notes for ftape-2.07, 04/03/96 =====
+
+
+- ftape updated to compile against 1.3.70.
+- Iomega 700 and Wangtek 3200 recognised.
+
+
+===== Release notes for ftape-2.06b, 13/02/96 =====
+
+Another simple bugfix version.
+
+- Jumbo 700 recognised.
+- Typo in vendors.h fixed.
+
+
+===== Release notes for ftape-2.06a, 10/02/96 =====
+
+This release is a simple bugfix version.
+
+- Linux/SMP: ftape *should* work.
+- FC-10/20: Only accepts IRQs 3-7, or 9.  If IRQ 9, properly tell the card
+  to use IRQ 2.  Thanks to Greg Crider (gcrider@iclnet.org) for finding and
+  locating this bug and testing the patch.
+- Insight drive recognised correctly again.
+- Motor-on wakeup version of the Iomega 250 drive added
+
+
+===== Release notes for ftape-2.06, 28/01/96 =====
+
+Special thanks go to Neal Friedman and Steven Sorbom for their
+help in producing and testing this release.
+
+I have continued to clean up the code, with an eye towards inclusion
+of ftape in Linus' official kernel (In fact, as I type this, I am
+running on a kernel with ftape support statically linked).  I have
+test-compiled ftape against my 1.2.13 tree without problems.
+Hopefully, everything should be OK for the v1.2.x people.
+
+WARNING! Alan Cox has mailed me that ftape does *NOT* work with
+Linux/SMP.  If you try to run ftape under Linux/SMP, it will cause a
+kernel deadlock (which is worse than a panic).
+
+- QIC-3020/TR-3: 1Mbps support works.  Neal is capable of reading and
+  writing data to a tape.  ftape will automatically detect the type of
+  tape (e.g. TR-3 vs QIC-80) and move the fdc in and out of
+  "perpendicular mode" as necessary.
+- 2Mbps support is disabled by default, since it is not fully
+  debugged.  If you are adventurous, remove -DFDC_82078SL in the
+  Makefile and see what happens :-)
+- fdc detection: silly bugs removed (Only 2Mbps fdcs were affected)
+  and added detection of the National Semiconductors PC8744 fdc chip
+  (used in the PC873xx "super-IO" chips).
+- Removed warning about incompatible types when compiling with Linux
+  1.2.x.
+- README.PCI updated with info about the DELL Dimension XPS P90.
+- Connor TST3200R added to detected drives.
+- `swapout' utility added to distribution.  It will dirty 5Meg of
+  memory, trying to swap out other programs.  Just say `make swapout'
+  to build it.  ftape will do this automatically Real Soon Now (ie:
+  when I have found out which kernel memory alloc function to call).
+
+
+===== Release notes for ftape-2.05, 08/01/96 =====
+
+- For v1.2.x Kernels, you must apply the patch linux-1.2/ksyms.patch to
+  the kernel and rebuild it (it adds the __get_dma_pages symbol to
+  ksyms.c).
+- Included new asm-i386/io.h file from v1.3.x kernel series, to enable
+  gcc v.2.7.[12] to compile v1.2.x kernels (linux-1.2/io.h).
+- Module versions: If you wish to compile ftape as a versioned module,
+  you must first compile your kernel with CONFIG_MODVERSIONS=y.
+  Otherwise, you will get complaints that <linux/modversions.h> does not
+  exist (if that happens, a `touch modversions.h' will help you out).
+- CLK_48MHZ: new define in the Makefile (default: non-zero).  If you have
+  a tape controller card that uses the i82078(-1) chip, but cannot get
+  it to work with ftape, try set it to 0 (and please report this).
+- QIC-3010/3020: Complete support is still missing, but will hopefully
+  come soon.  Steven Sorbom has kindly provided me with hints about
+  this.  Writing of QIC-3020 tapes definitely does NOT work (do not try
+  it! - the drive will not be in "perpendicular mode" and this will ruin
+  the formatting info on the tape).
+- ftape_num_buffers is out of fashion: use NR_BUFFERS instead (and
+  recompile if you want to change it :-).
+
+
+===== Release notes for ftape-2.04, 01/01/96 =====
+
+This version by Kai Harrekilde-Petersen <khp@dolphinics.no>
+
+- ALERT! Support for Kernels earlier then v1.1.85 is about to go away.
+  I intend to clean up some of the code (getting rid of an annoyingly
+  large numbers of #ifdef mostly), which means that support for
+  pre-1.1.85 kernels must go as well.
+- NR_FTAPE_BUFFERS is gone; You can instead select the number of dma
+  buffers by saying `insmod ftape.o ftape_num_buffer=<n>' instead.
+- Configure script gone.  ftape will now automagically determine your
+  kernel version by /usr/include/linux/version.h instead.
+- CONFIG_MODVERSIONS now work.  All combinations of versioned /
+  unversioned kernel and ftape module works (at least with my 1.3.52
+  kernel).
+- If you have problems with inserting ftape into an old (1.2.x)
+  kernel (e.g. insmod says "1.2.8 does not match 1.2.8), recompile
+  your modules utilities with your new compiler.
+- Reveal TB1400 drive added to vendors.h
+- Support for the i82078-1 (2Mbps) chip is coming along.  The
+  biggest problem is that I don't have such a card, which makes
+  testing / debugging somewhat problematic.  The second biggest
+  problem is that I do not have the QIC-3010/3020 standards either.
+  Status right now is that the chip is detected, and it should be
+  possible to put it into 2Mbps mode.  However, I do not know what
+  "extras" are needed to complete the support.  Although putting the
+  i82078 into 1Mbps mode ought to work out of the box, it doesn't
+  (right now, ftape complains about id am errors).
+
+
+===== Release notes for ftape-2.04beta5, 29/12/95 =====
+
+Bas offline linux-tape
+----------------------
+For reasons only known to the majordomo mail list processor, Bas was
+kicked off the linux-tape list sometime during the summer.  Being
+overworked at his for-pay job, he didn't notice it much.  Instead I
+(Kai, khp@dolphinics.no) has worked on ftape to produce the 2.04(beta)
+version.
+
+zftape
+------
+Note that there exists a much improved version of ftape, written by
+Claus-Justus Heine <claus@willi.math.rwth-aachen.de> which is named
+zftape, which conforms to the QIC-80 specs on how to mark backups, and
+is capable of doing automatic compression.  However, zftape makes
+substantial changes to ftape, and I (Kai) have therefore declined to
+integrate zftape into ftape.  Hopefully, this will happen soon.
+
+CONFIG_QIC117 removed from the kernel
+-------------------------------------
+The biggest change of all is that ftape now will allocate its dma
+buffers when it is inserted.  The means that the CONFIG_QIC117 option
+has disappeared from the Linux kernel as of v1.3.34.  If you have an
+earlier kernel, simply answer 'no' to the question will do the trick
+(if you get complains about __get_free_pages() missing, contact the
+linux-tape mailing list).
+
+Note that ftape-2.04beta will work equally well on kernels with and
+without `ftape support'.  The only catch is, that you will waste
+around 96-128Kb of precious DMA'able memory on a box that has ftape
+support compiled in.
+
+Now for the real changes:
+
+- FC-20 can now use DMA channels 1, 2, and 3. Thanks to Daniel
+  Cohen, catman@wpi.edu.
+- ftape no longer requires a (gigantic) 96Kb buffer to be statically
+  allocated by the kernel.
+- Added new Iomega drive (8882) to vendors.h
+- -fno-strength-reduce added to Makefile, since GCC is broken.
+- i82078-1 (2Mbps) FDC support started.
+
+
+===== Release notes for ftape-2.03b, 27/05/95 =====
+
+- Prevented verify_area to return error if called with zero length.
+- Fixed a bug in flush_buffers that caused too much padding to be
+  written when a final segment had bad sectors.
+- Increased maximum fast-seek overshoot value from 5 to 10 segments.
+- Breaking loop after 5 retries when positioning fails.
+- Fixed wrong calculation of tape length for QIC-3010 and QIC-3020
+  tapes (densities were swapped).
+- Fixed wrong calculation of overshoot on seek_forward: Wrong sign
+  of error.
+- Suppress (false) error message due to new tape loaded.
+- Added two new CMS drives (11c3 and 11c5) to vendors.h.
+
+
+===== Release notes for ftape-2.03a, 09/05/95 =====
+
+- Fixed display of old error (even if already cleared) in ftape_open.
+- Improved tape length detection, ioctls would fail for 425 ft tapes.
+  Until the tape length is calculated with data from the header
+  segment, we'll use worst-case values.
+- Clear eof_mark after rewinding ioctls.
+- Fixed wrong version message (2.03 had 2.02g id).
+- Fixed bug that caused the fdc to be reset very frequently.
+  This shouldn't affect normal operation but the timing of the
+  report routines has changed again and that may cause problems.
+  We'll just have to find out....
+- Implemented correct write precompensation setting for QIC-3010/3020.
+- Cleaned up fdc_interrupt_wait routine. Hope it still works :-)
+- Finally removed (already disabled) special eof mark handling for
+  gnu tar.
+- Changed order of get_dma_residue and disable_dma in fdc-isr.c
+  because the current order would fail on at least one system.
+  We're back to the original order again, hope (and expect) this
+  doesn't break any other system.
+
+
+===== Release notes for ftape-2.03, 07/05/95 =====
+
+(Changes refer to the first ftape-2.02 release)
+
+Support for wide and extended length tapes
+------------------------------------------
+The Conner TSM 420 and 850 drives are reported to be working.
+I haven't received any reports about other brands; the TSM 420
+and 850 seem to be the most widely used wide drives.
+Extended length tapes (425 ft) with normal QIC-80 drives
+are operating too (At least I've had no reports stating otherwise).
+_Not_ yet completely supported (although they may work) are
+QIC-3020 drives and 2 Mbps floppy disk controllers won't work at
+the highest speed.
+If someone is kind enough to send me one of these, I'll include
+support for it too ;-)
+
+Easier configuration
+--------------------
+Problems due to wrong settings in the Makefile are prevented
+by using a configuration script that sets the necessary (kernel
+version dependent) compile time options.
+This kernel version is now determined from the sources found
+at /usr/src/linux, or if not found, the old way using
+/proc/version.
+Versioned modules will be used automatically when supported
+by- and configured in- the kernel.
+Note that the current modules code (1.1.87) is still broken
+and _needs_ the fix included in the insmod directory.
+Please don't send me any more Oops reports caused by insmod :-(
+
+Reduced module size
+-------------------
+The standard module size is much reduced and some compile time
+options can even reduce it further. (I don't recommend this
+for normal use but it can be handy for rescue diskettes)
+
+Option:           Approx. module size:
+
+<standard>             150 Kb
+NO_TRACE               125 Kb
+NO_TRACE_AT_ALL         67 Kb
+
+
+Much improved driver interruption
+---------------------------------
+Most possible loops have been broken and signal detection
+has been improved.
+In most cases the driver can be aborted by ^C (SIGINT) and
+SIGKILL (kill -9) will generate be a sure kill.
+(Note that aborting a tape operation may damage the last
+data written to tape)
+
+Improved error recovery
+-----------------------
+Ftape now returns an error (ENODATA) to the application if
+a segment proves to be unrecoverable and then skips the
+bad segment.
+This causes most applications to continue to work (tar
+and afio) loosing only a small amount (up to 29 Kb) of data.
+Retried read operations will now be done slightly off-track
+to improve the chance of success. Serious head off-track
+errors will be detected.
+
+FC-10 and FC-20 controllers
+---------------------------
+Ftape now supports both the old CMS FC-10 and the newer FC-20
+controllers.
+Because the operation of these cards is still undocumented,
+thus far they will only work with the default settings (See
+Makefile). Any feed-back on how to use them with other settings
+will be welcome !
+Compilation will fail if one changes the settings to illegal
+values.
+
+Kernels and compilers
+---------------------
+Ftape is currently being developed using the 2.5.8 compiler.
+The older 2.4.5 probably works too (Set option in Makefile!).
+I have no experience with any later compilers nor Elf support.
+Any information on this is welcome.
+The latest kernel I have tested ftape with is 1.2.6.
+
+Compression
+-----------
+An impressive collection of changes for ftape including
+on-the-fly compression is still lying on my desk.
+If 2.03 proves to be reliable I might start integrating these
+but as usual, I'm short in time :-(
+
+Formatting
+----------
+There is still no way to format tapes under Linux. As far as
+I know all attempts to write such a program have died now.
+Since formatted tapes are rather common now, I think all we
+need is a utility that writes a worst case pattern and verifies
+that with the drive put in verify mode, reducing margins.
+Any takers ?
+
+Furthermore
+-----------
+Cleaned up messages.
+Prepared to support multiple tape drives on one fdc.
+Thanks to all the people who sent bug reports and helped me
+improve the driver. Without trying to be complete I'll mention
+Gary Anderson (without his accurate reports and unreliable
+hardware there wouldn't be a 2.03), Stefan Kneifel (FC-20),
+Robert Broughton (FC-20, you were almost there ;-), Bjorn
+Ekwall (for the versioned modules and buggy insmod ;-), Peter
+Fox, Christopher Oliver, Ralph Whittaker and not the least
+Linus Torvalds (for Linux and keeping me busy because of
+changes to the kernel ;-)
+Thanks to anyone I forgot, for the bug reports, the ftape
+bashing and the mental support...
+
+
+That's it for now. Have Fun,
+
+Bas.
+
+
+===== Release notes for ftape-2.02g, 06/05/95 =====
+
+- Added extra test to break read-id loop with signal.
+- Changed rewind code to handle negative overshoot for drives
+  that take very long to start or stop.
+- Let use of get/set i/o-regions depend on kernel version.
+- Changed code to use a more general test for conditional
+  compilations depending on kernel version.
+- Improved micro-step functionality to go off-track only
+  while reading (id & data).
+- Added failure on tape-not-referenced bit in ftape_command.
+- Added FOREVER option to read-wait routine.
+- Changed read-id to use shorter timeout causing smaller
+  rewinds on timeout.
+- Made kernel-interface functions static.
+
+
+===== Release notes for ftape-2.02f, 03/05/95 =====
+
+- Added support for dual tape drives on my system, extended Configure
+  script to detect host 'dodo'.
+- Log media defect in history if ecc failed and no data was returned.
+- Fixed Configure script that was failing for kernel versions with
+  double digit version or revision numbers.
+
+
+===== Release notes for ftape-2.02e, 01/05/95 =====
+
+- Fixed reposition loop at logical eot (failing read_id).
+- Fixed 34 segment offset when rewinding.
+- Added fast seek capability for more than 255 segments.
+- Fixed wrong busy result from ftape_command causing reverse
+  seek to fail.
+- Added breakout from infinite rewind loop (if something fails).
+
+
+===== Release notes for ftape-2.02d, 30/04/95 =====
+
+- Improved abortion on signals: Interrupt will make a graceful
+  exit, Kill will be less nice and should be used if everything
+  else fails.
+- Included check for tape-head off track.
+- Implemented exit from tape-start loop.
+- Added kernel io-port registration.
+- Implemented skip of failing segment (ENODATA) on ecc failure.
+  This allows afio and tar to continue when the tape is damaged.
+- Made distinction between drive names with different codes.
+
+
+===== Release notes for ftape-2.02c, 22/04/95 =====
+
+- Fixed too tight command queueing after tape stop/pause command
+  issued from within interrupt service routine (Showed as timeout
+  on Acknowledge errors during retries on some systems)
+- Tried to fix timeouts when using 425 ft tape because the extended
+  length doesn't seem to be detected by the hardware.
+  We now use the format code from the header segment so adjust the
+  timing after reading the header segment.
+- Fixed some messages stating 'unexpected something...' being not
+  unexpected anymore.
+- Started preparations for merge of dynamic buffer allocation and
+  compression code.
+- Changed some debug messages to include relevant segment information
+  at level 4.
+- Included early bail-out when drive offline, preventing a lot of
+  false messages.
+- Moved ftape_parameter_xxx() offsets into function instead of in calls.
+- Removed 'weird, drive busy but no data' error when caused by
+  an error during a read-id.
+- Improved 'timeout on acknowledge' diagnostics.
+- Moved MODULE option into Configure.
+- Reduced code size when no tracing at all was set (Claus Heine).
+- No longer log error code 0 (no error) as an error.
+
+
+===== Release notes for ftape-2.02b, 09/04/95 =====
+
+- Relaxed timing for status operation and displaying
+  abnormal results. Hopefully this shows what's going
+  wrong with the Conner TSM850R drives.
+- Created script for configuration, using version number
+  of kernel source if available, otherwise /proc/version.
+- Fixed conditionals in kernel-interface.c.
+- Removed unavoidable TRACE output.
+
+
+===== Release notes for ftape-2.02a, 01/04/95 =====
+
+- Implemented `new-style' (versioned) modules support for new
+  kernels.
+- Reduced size of module by moving static data to bss.
+- Now using version number of kernel source instead of running
+  kernel for kernel versions >= 1.1.82
+- Added feedback on drive speeds to vendor information.
+- Included fixed insmod sources to distribution (Let's hope
+  the modules distribution get fixed soon :-/).
+
+Note that I haven't yet implemented any of the code extension I
+received. I hope to find some time to do this soon.
+
+
+===== Release notes for ftape-2.02, 15/01/95 =====
+
+
+- Fixed failing repositioning when overshoot was incremented.
+- Fixed rate selection: Because of a deficiency in the QIC-117
+  specification one cannot distinguish between a not implemented
+  and a failing command. Therefor we now try to find out if the
+  drive does support this command before usage.
+- Fixed error retry using wrong offset in fdc-isr.
+- Improved retry code to retry only once on a single no-data
+  error in a segment.
+- Validate sector number extracted from eof mark because an
+  invalid file mark (due to ???) could cause kernel panic.
+- Split ftape-io.c into ftape-io.c and ftape-ctl.c files.
+- Corrected too high media error count after writing to
+  a bad tape.
+- Added #include <asm/segment.h> again because old kernel versions
+  need it.
+- Fixed fdc not being disabled when open failed because no tape
+  drive was found.
+- Fixed problem with soft error in sector 32 (shift operator with
+  shiftcount 32 is not defined).
+
+
+===== Release notes for ftape-2.01, 08/01/95 =====
+
+
+- Removed TESTING setting from distributed Makefile.
+- Fixed `mt asf' failure: Rewind was deferred to close which
+  overruled the fsf ioctl.
+- Prevented non-interruptible commands being interrupted.
+- Added missing timeout.pause setting.
+- Maximum tape speed read from drive type information table.
+  If the information is not in the table (0) the drive will
+  determine the speed itself and put a message in the logfile.
+  This information should then be added to the table in the
+  vendors.h file (and reported to me).
+- Added call to ftape_init_drive after soft reset for those
+  (antique) drives that don't do an implicit seek_load_point
+  after a reset or power up.
+- Don't try to set data rate if reset failed.
+- Prevent update of seek variables when starting from the
+  beginning or the end of the tape.
+- Fixed wrong adjustment of overshoot in seek_forward().
+- Added sync to Makefile (again).
+- Added code to diagnose timer problems (calibr.c).
+- Replaced time differences by timediff calls.
+- Removed reference to do_floppy from object for recent kernels.
+- Fixed wrong display of 'failing dma controller' message.
+- Removed various no longer used #include statements.
+- Added max. tape speed value to vendor-struct.
+- Changed ftape-command to check pre-conditions and wait
+  if needed.
+- Further updated qic117.h to rev G.
+- Combined command name table and restrictions table to one.
+  Extended this table with some new fields.
+- Increased timeout on Ack timer value and included code to
+  report out of spec behaviour.
+- Increased rewind timeout margin to calculated + 20%.
+- Improved data rate selection so it won't fail on some
+  older (pre standard) drives.
+- Changed initialisation code so drive will be rewound if the
+  driver is reloaded and the tape is not at bot.
+- Moved some of the flush operations from close to the ioctls.
+- Added exit code value to failing verify area message.
+- Loop until tape halted in smart-stop.
+- Fast seek handled specially if located at bot or eot.
+- Being more conservative on overshoot value.
+
+
+===== Release notes for ftape-2.00, 31/12/94 =====
+
+  The Install-guide is completely rewritten and now also includes
+some information on how to use the driver. If you're either new
+to ftape or new to Unix tape devices make sure to read it !
+
+  If you own a pci system and experience problems with the
+ftape driver make sure to read the README.PCI file. It contains
+some hints on how to fix your hardware.
+
+  For anybody who hasn't noticed: The version number of the
+driver has been incremented (The latest released version has
+been version 1.14d).
+  This has been done for two major reasons:
+
+  o  A new (better) error recovery scheme is implemented.
+  o  Support for new drive types has been added.
+
+  All these improvements/changes will probably include a couple
+of new (and old?) bugs. If you encounter any problems that you think
+I'm not yet aware of, feel free to send a report to <bas@vimec.nl>.
+  I recommend keeping a version of ftape-1.14d available, just
+in case ;-)
+
+  This version should work with all kernel versions from 1.0.9 up
+to 1.1.72 (and probably earlier and later versions too).
+
+
+Major new features:
+
+- Better handling of tapes with defects: When a sector repeatedly
+  (SOFT_RETRIES in ftape.h) cannot be written to or read from it is
+  marked as an hard error and gets skipped.
+  The error correction code can handle up to three of these hard
+  errors provided there are no other errors in that segment (32 Kb).
+  
+- Allows writing to tapes with defects (although the risk of loosing
+  data increases !)
+  Look for the media-defects entry printed with the statistics when
+  the tape is closed. A non-zero value here shows a bad tape.
+  [the actual count is wrong (too high), this is a known bug].
+
+- Use of backup header segment if first one is failing.
+
+- Support for extended length tapes with QIC-80: both 425 and 1100 ft.
+  0.25 inch tapes are now recognized and handled.
+
+- Support for new QIC-80 drives with 8 mm `wide' tapes (e.g. Conner
+  TSM 420).
+
+- Support for new QIC-3010 and QIC-3020 drives (experimental) with
+  both 0.25 inch and 8 mm tapes.
+
+Some minor features were added, a couple of small bugs were fixed and
+probably some new ones introduced ;-).
+
+[lseek() didn't make it into this version]
+
+Have fun,
+
+Bas.
+----
+ LocalWords:  ftape MCONFIG mt VFS zftape resp sftape proc subdir MTIOCVOLINFO
+ LocalWords:  MTIOCGETSIZE BOT EOD MTBSF zft kerneld modprobe kdtime contrib TR
+ LocalWords:  MTSETBLK afio uninstall texi www EIO QIC init sft eof aka dma GB
+ LocalWords:  SIGKILL MTIOCFTCMD mmap Iomega FDC fdc io gnumt mtio fc asm inb
+ LocalWords:  outb ft qic frontend TeXinfo irq mach MODVERSIONS CONFIG html dvi
+ LocalWords:  usr doc SMP Mb Dunno FIXME vtblc perl listtape volinfo fsf MTWEOF
+ LocalWords:  amanda degaussed ComByte DoublePlay whraven njackn com MTIOC vtbl
+ LocalWords:  GETBLKSZ MAKEDEV zftape's linux dif CVS Revison cp MTREW MTOFFL
+ LocalWords:  MTFSF BSF Marcin Dalecki GCC Config cpio swapout Kai Harrekilde
+ LocalWords:  Pederson khp dolphinics Justus claus momo rwth aachen Laarhoven
diff --git a/drivers/char/ftape/compressor/Makefile b/drivers/char/ftape/compressor/Makefile
new file mode 100644
index 0000000..1fbd6c4
--- /dev/null
+++ b/drivers/char/ftape/compressor/Makefile
@@ -0,0 +1,31 @@
+#
+#       Copyright (C) 1997 Claus-Justus Heine.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; see the file COPYING.  If not, write to
+# the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+#
+# $Source: /homes/cvs/ftape-stacked/ftape/compressor/Makefile,v $
+# $Revision: 1.1 $
+# $Date: 1997/10/05 19:12:28 $
+#
+#      Makefile for the optional compressor for th zftape VFS
+#      interface to the QIC-40/80/3010/3020 floppy-tape driver for
+#      Linux.
+#
+
+obj-$(CONFIG_ZFT_COMPRESSOR) += zft-compressor.o
+
+zft-compressor-objs := zftape-compress.o lzrw3.o
+
+CFLAGS_lzrw3.o	:= -O6 -funroll-all-loops
diff --git a/drivers/char/ftape/compressor/lzrw3.c b/drivers/char/ftape/compressor/lzrw3.c
new file mode 100644
index 0000000..a032a0e
--- /dev/null
+++ b/drivers/char/ftape/compressor/lzrw3.c
@@ -0,0 +1,743 @@
+/*
+ * $Source: /homes/cvs/ftape-stacked/ftape/compressor/lzrw3.c,v $
+ * $Revision: 1.1 $
+ * $Date: 1997/10/05 19:12:29 $
+ *
+ * Implementation of Ross Williams lzrw3 algorithm. Adaption for zftape.
+ *
+ */
+
+#include "../compressor/lzrw3.h"       /* Defines single exported function "compress".   */
+
+/******************************************************************************/
+/*                                                                            */
+/*                                    LZRW3.C                                 */
+/*                                                                            */
+/******************************************************************************/
+/*                                                                            */
+/* Author  : Ross Williams.                                                   */
+/* Date    : 30-Jun-1991.                                                     */
+/* Release : 1.                                                               */
+/*                                                                            */
+/******************************************************************************/
+/*                                                                            */
+/* This file contains an implementation of the LZRW3 data compression         */
+/* algorithm in C.                                                            */
+/*                                                                            */
+/* The algorithm is a general purpose compression algorithm that runs fast    */
+/* and gives reasonable compression. The algorithm is a member of the Lempel  */
+/* Ziv family of algorithms and bases its compression on the presence in the  */
+/* data of repeated substrings.                                               */
+/*                                                                            */
+/* This algorithm is unpatented and the code is public domain. As the         */
+/* algorithm is based on the LZ77 class of algorithms, it is unlikely to be   */
+/* the subject of a patent challenge.                                         */
+/*                                                                            */
+/* Unlike the LZRW1 and LZRW1-A algorithms, the LZRW3 algorithm is            */
+/* deterministic and is guaranteed to yield the same compressed               */
+/* representation for a given file each time it is run.                       */
+/*                                                                            */
+/* The LZRW3 algorithm was originally designed and implemented                */
+/* by Ross Williams on 31-Dec-1990.                                           */
+/*                                                                            */
+/* Here are the results of applying this code, compiled under THINK C 4.0     */
+/* and running on a Mac-SE (8MHz 68000), to the standard calgary corpus.      */
+/*                                                                            */
+/*    +----------------------------------------------------------------+      */
+/*    | DATA COMPRESSION TEST                                          |      */
+/*    | =====================                                          |      */
+/*    | Time of run     : Sun 30-Jun-1991 09:31PM                      |      */
+/*    | Timing accuracy : One part in 100                              |      */
+/*    | Context length  : 262144 bytes (= 256.0000K)                   |      */
+/*    | Test suite      : Calgary Corpus Suite                         |      */
+/*    | Files in suite  : 14                                           |      */
+/*    | Algorithm       : LZRW3                                        |      */
+/*    | Note: All averages are calculated from the un-rounded values.  |      */
+/*    +----------------------------------------------------------------+      */
+/*    | File Name   Length  CxB  ComLen  %Remn  Bits  Com K/s  Dec K/s |      */
+/*    | ----------  ------  ---  ------  -----  ----  -------  ------- |      */
+/*    | rpus:Bib.D  111261    1   55033   49.5  3.96    19.46    32.27 |      */
+/*    | us:Book1.D  768771    3  467962   60.9  4.87    17.03    31.07 |      */
+/*    | us:Book2.D  610856    3  317102   51.9  4.15    19.39    34.15 |      */
+/*    | rpus:Geo.D  102400    1   82424   80.5  6.44    11.65    18.18 |      */
+/*    | pus:News.D  377109    2  205670   54.5  4.36    17.14    27.47 |      */
+/*    | pus:Obj1.D   21504    1   13027   60.6  4.85    13.40    18.95 |      */
+/*    | pus:Obj2.D  246814    1  116286   47.1  3.77    19.31    30.10 |      */
+/*    | s:Paper1.D   53161    1   27522   51.8  4.14    18.60    31.15 |      */
+/*    | s:Paper2.D   82199    1   45160   54.9  4.40    18.45    32.84 |      */
+/*    | rpus:Pic.D  513216    2  122388   23.8  1.91    35.29    51.05 |      */
+/*    | us:Progc.D   39611    1   19669   49.7  3.97    18.87    30.64 |      */
+/*    | us:Progl.D   71646    1   28247   39.4  3.15    24.34    40.66 |      */
+/*    | us:Progp.D   49379    1   19377   39.2  3.14    23.91    39.23 |      */
+/*    | us:Trans.D   93695    1   33481   35.7  2.86    25.48    40.37 |      */
+/*    +----------------------------------------------------------------+      */
+/*    | Average     224401    1  110953   50.0  4.00    20.17    32.72 |      */
+/*    +----------------------------------------------------------------+      */
+/*                                                                            */
+/******************************************************************************/
+
+/******************************************************************************/
+
+/* The following structure is returned by the "compress" function below when  */
+/* the user asks the function to return identifying information.              */
+/* The most important field in the record is the working memory field which   */
+/* tells the calling program how much working memory should be passed to      */
+/* "compress" when it is called to perform a compression or decompression.    */
+/* LZRW3 uses the same amount of memory during compression and decompression. */
+/* For more information on this structure see "compress.h".                   */
+  
+#define U(X)            ((ULONG) X)
+#define SIZE_P_BYTE     (U(sizeof(UBYTE *)))
+#define SIZE_WORD       (U(sizeof(UWORD  )))
+#define ALIGNMENT_FUDGE (U(16))
+#define MEM_REQ ( U(4096)*(SIZE_P_BYTE) + ALIGNMENT_FUDGE )
+
+static struct compress_identity identity =
+{
+ U(0x032DDEA8),                           /* Algorithm identification number. */
+ MEM_REQ,                                 /* Working memory (bytes) required. */
+ "LZRW3",                                 /* Name of algorithm.               */
+ "1.0",                                   /* Version number of algorithm.     */
+ "31-Dec-1990",                           /* Date of algorithm.               */
+ "Public Domain",                         /* Copyright notice.                */
+ "Ross N. Williams",                      /* Author of algorithm.             */
+ "Renaissance Software",                  /* Affiliation of author.           */
+ "Public Domain"                          /* Vendor of algorithm.             */
+};
+ 
+LOCAL void compress_compress  (UBYTE *,UBYTE *,ULONG,UBYTE *, LONG *);
+LOCAL void compress_decompress(UBYTE *,UBYTE *,LONG, UBYTE *, ULONG *);
+
+/******************************************************************************/
+
+/* This function is the only function exported by this module.                */
+/* Depending on its first parameter, the function can be requested to         */
+/* compress a block of memory, decompress a block of memory, or to identify   */
+/* itself. For more information, see the specification file "compress.h".     */
+
+EXPORT void lzrw3_compress(
+	UWORD     action,      /* Action to be performed.		*/
+	UBYTE   *wrk_mem,	/* Address of working memory we can use.*/
+	UBYTE   *src_adr,	/* Address of input data.		*/
+	LONG     src_len,	/* Length  of input data.		*/
+	UBYTE   *dst_adr,	/* Address to put output data.		*/
+	void  *p_dst_len	/* Address of longword for length of output data.*/
+)
+{
+ switch (action)
+   {
+    case COMPRESS_ACTION_IDENTITY:
+       *((struct compress_identity **)p_dst_len)= &identity;
+       break;
+    case COMPRESS_ACTION_COMPRESS:
+       compress_compress(wrk_mem,src_adr,src_len,dst_adr,(LONG *)p_dst_len);
+       break;
+    case COMPRESS_ACTION_DECOMPRESS:
+       compress_decompress(wrk_mem,src_adr,src_len,dst_adr,(LONG *)p_dst_len);
+       break;
+   }
+}
+
+/******************************************************************************/
+/*                                                                            */
+/* BRIEF DESCRIPTION OF THE LZRW3 ALGORITHM                                   */
+/* ========================================                                   */
+/* The LZRW3 algorithm is identical to the LZRW1-A algorithm except that      */
+/* instead of transmitting history offsets, it transmits hash table indexes.  */
+/* In order to decode the indexes, the decompressor must maintain an          */
+/* identical hash table. Copy items are straightforward:when the decompressor */
+/* receives a copy item, it simply looks up the hash table to translate the   */
+/* index into a pointer into the data already decompressed. To update the     */
+/* hash table, it replaces the same table entry with a pointer to the start   */
+/* of the newly decoded phrase. The tricky part is with literal items, for at */
+/* the time that the decompressor receives a literal item the decompressor    */
+/* does not have the three bytes in the Ziv (that the compressor has) to      */
+/* perform the three-byte hash. To solve this problem, in LZRW3, both the     */
+/* compressor and decompressor are wired up so that they "buffer" these       */
+/* literals and update their hash tables only when three bytes are available. */
+/* This makes the maximum buffering 2 bytes.                                  */
+/*                                                                            */
+/* Replacement of offsets by hash table indexes yields a few percent extra    */
+/* compression at the cost of some speed. LZRW3 is slower than LZRW1, LZRW1-A */
+/* and LZRW2, but yields better compression.                                  */
+/*                                                                            */
+/* Extra compression could be obtained by using a hash table of depth two.    */
+/* However, increasing the depth above one incurs a significant decrease in   */
+/* compression speed which was not considered worthwhile. Another reason for  */
+/* keeping the depth down to one was to allow easy comparison with the        */
+/* LZRW1-A and LZRW2 algorithms so as to demonstrate the exact effect of the  */
+/* use of direct hash indexes.                                                */
+/*                                                                            */
+/*                                  +---+                                     */
+/*                                  |___|4095                                 */
+/*                                  |___|                                     */
+/*              +---------------------*_|<---+   /----+---\                   */
+/*              |                   |___|    +---|Hash    |                   */
+/*              |                   |___|        |Function|                   */
+/*              |                   |___|        \--------/                   */
+/*              |                   |___|0            ^                       */
+/*              |                   +---+             |                       */
+/*              |                   Hash        +-----+                       */
+/*              |                   Table       |                             */
+/*              |                              ---                            */
+/*              v                              ^^^                            */
+/*      +-------------------------------------|----------------+              */
+/*      ||||||||||||||||||||||||||||||||||||||||||||||||||||||||              */
+/*      +-------------------------------------|----------------+              */
+/*      |                                     |1......18|      |              */
+/*      |<------- Lempel=History ------------>|<--Ziv-->|      |              */
+/*      |     (=bytes already processed)      |<-Still to go-->|              */
+/*      |<-------------------- INPUT BLOCK ------------------->|              */
+/*                                                                            */
+/* The diagram above for LZRW3 looks almost identical to the diagram for      */
+/* LZRW1. The difference is that in LZRW3, the compressor transmits hash      */
+/* table indices instead of Lempel offsets. For this to work, the             */
+/* decompressor must maintain a hash table as well as the compressor and both */
+/* compressor and decompressor must "buffer" literals, as the decompressor    */
+/* cannot hash phrases commencing with a literal until another two bytes have */
+/* arrived.                                                                   */
+/*                                                                            */
+/*  LZRW3 Algorithm Execution Summary                                         */
+/*  ---------------------------------                                         */
+/*  1. Hash the first three bytes of the Ziv to yield a hash table index h.   */
+/*  2. Look up the hash table yielding history pointer p.                     */
+/*  3. Match where p points with the Ziv. If there is a match of three or     */
+/*     more bytes, code those bytes (in the Ziv) as a copy item, otherwise    */
+/*     code the next byte in the Ziv as a literal item.                       */
+/*  4. Update the hash table as possible subject to the constraint that only  */
+/*     phrases commencing three bytes back from the Ziv can be hashed and     */
+/*     entered into the hash table. (This enables the decompressor to keep    */
+/*     pace). See the description and code for more details.                  */
+/*                                                                            */
+/******************************************************************************/
+/*                                                                            */
+/*                     DEFINITION OF COMPRESSED FILE FORMAT                   */
+/*                     ====================================                   */
+/*  * A compressed file consists of a COPY FLAG followed by a REMAINDER.      */
+/*  * The copy flag CF uses up four bytes with the first byte being the       */
+/*    least significant.                                                      */
+/*  * If CF=1, then the compressed file represents the remainder of the file  */
+/*    exactly. Otherwise CF=0 and the remainder of the file consists of zero  */
+/*    or more GROUPS, each of which represents one or more bytes.             */
+/*  * Each group consists of two bytes of CONTROL information followed by     */
+/*    sixteen ITEMs except for the last group which can contain from one      */
+/*    to sixteen items.                                                       */
+/*  * An item can be either a LITERAL item or a COPY item.                    */
+/*  * Each item corresponds to a bit in the control bytes.                    */
+/*  * The first control byte corresponds to the first 8 items in the group    */
+/*    with bit 0 corresponding to the first item in the group and bit 7 to    */
+/*    the eighth item in the group.                                           */
+/*  * The second control byte corresponds to the second 8 items in the group  */
+/*    with bit 0 corresponding to the ninth item in the group and bit 7 to    */
+/*    the sixteenth item in the group.                                        */
+/*  * A zero bit in a control word means that the corresponding item is a     */
+/*    literal item. A one bit corresponds to a copy item.                     */
+/*  * A literal item consists of a single byte which represents itself.       */
+/*  * A copy item consists of two bytes that represent from 3 to 18 bytes.    */
+/*  * The first  byte in a copy item will be denoted C1.                      */
+/*  * The second byte in a copy item will be denoted C2.                      */
+/*  * Bits will be selected using square brackets.                            */
+/*    For example: C1[0..3] is the low nibble of the first control byte.      */
+/*    of copy item C1.                                                        */
+/*  * The LENGTH of a copy item is defined to be C1[0..3]+3 which is a number */
+/*    in the range [3,18].                                                    */
+/*  * The INDEX of a copy item is defined to be C1[4..7]*256+C2[0..8] which   */
+/*    is a number in the range [0,4095].                                      */
+/*  * A copy item represents the sequence of bytes                            */
+/*       text[POS-OFFSET..POS-OFFSET+LENGTH-1] where                          */
+/*          text   is the entire text of the uncompressed string.             */
+/*          POS    is the index in the text of the character following the    */
+/*                   string represented by all the items preceeding the item  */
+/*                   being defined.                                           */
+/*          OFFSET is obtained from INDEX by looking up the hash table.       */
+/*                                                                            */
+/******************************************************************************/
+
+/* The following #define defines the length of the copy flag that appears at  */
+/* the start of the compressed file. The value of four bytes was chosen       */
+/* because the fast_copy routine on my Macintosh runs faster if the source    */
+/* and destination blocks are relatively longword aligned.                    */
+/* The actual flag data appears in the first byte. The rest are zeroed so as  */
+/* to normalize the compressed representation (i.e. not non-deterministic).   */
+#define FLAG_BYTES 4
+
+/* The following #defines define the meaning of the values of the copy        */
+/* flag at the start of the compressed file.                                  */
+#define FLAG_COMPRESS 0     /* Signals that output was result of compression. */
+#define FLAG_COPY     1     /* Signals that output was simply copied over.    */
+
+/* The 68000 microprocessor (on which this algorithm was originally developed */
+/* is fussy about non-aligned arrays of words. To avoid these problems the    */
+/* following macro can be used to "waste" from 0 to 3 bytes so as to align    */
+/* the argument pointer.                                                      */
+#define ULONG_ALIGN_UP(X) ((((ULONG)X)+sizeof(ULONG)-1)&~(sizeof(ULONG)-1))
+
+
+/* The following constant defines the maximum length of an uncompressed item. */
+/* This definition must not be changed; its value is hardwired into the code. */
+/* The longest number of bytes that can be spanned by a single item is 18     */
+/* for the longest copy item.                                                 */
+#define MAX_RAW_ITEM (18)
+
+/* The following constant defines the maximum length of an uncompressed group.*/
+/* This definition must not be changed; its value is hardwired into the code. */
+/* A group contains at most 16 items which explains this definition.          */
+#define MAX_RAW_GROUP (16*MAX_RAW_ITEM)
+
+/* The following constant defines the maximum length of a compressed group.   */
+/* This definition must not be changed; its value is hardwired into the code. */
+/* A compressed group consists of two control bytes followed by up to 16      */
+/* compressed items each of which can have a maximum length of two bytes.     */
+#define MAX_CMP_GROUP (2+16*2)
+
+/* The following constant defines the number of entries in the hash table.    */
+/* This definition must not be changed; its value is hardwired into the code. */
+#define HASH_TABLE_LENGTH (4096)
+
+/* LZRW3, unlike LZRW1(-A), must initialize its hash table so as to enable    */
+/* the compressor and decompressor to stay in step maintaining identical hash */
+/* tables. In an early version of the algorithm, the tables were simply       */
+/* initialized to zero and a check for zero was included just before the      */
+/* matching code. However, this test costs time. A better solution is to      */
+/* initialize all the entries in the hash table to point to a constant        */
+/* string. The decompressor does the same. This solution requires no extra    */
+/* test. The contents of the string do not matter so long as the string is    */
+/* the same for the compressor and decompressor and contains at least         */
+/* MAX_RAW_ITEM bytes. I chose consecutive decimal digits because they do not */
+/* have white space problems (e.g. there is no chance that the compiler will  */
+/* replace more than one space by a TAB) and because they make the length of  */
+/* the string obvious by inspection.                                          */
+#define START_STRING_18 ((UBYTE *) "123456789012345678")
+
+/* In this algorithm, hash values have to be calculated at more than one      */
+/* point. The following macro neatens the code up for this.                   */
+#define HASH(PTR) \
+   (((40543*(((*(PTR))<<8)^((*((PTR)+1))<<4)^(*((PTR)+2))))>>4) & 0xFFF)
+
+/******************************************************************************/
+
+/* Input  : Hand over the required amount of working memory in p_wrk_mem.     */
+/* Input  : Specify input block using p_src_first and src_len.                */
+/* Input  : Point p_dst_first to the start of the output zone (OZ).           */
+/* Input  : Point p_dst_len to a ULONG to receive the output length.          */
+/* Input  : Input block and output zone must not overlap.                     */
+/* Output : Length of output block written to *p_dst_len.                     */
+/* Output : Output block in Mem[p_dst_first..p_dst_first+*p_dst_len-1]. May   */
+/* Output : write in OZ=Mem[p_dst_first..p_dst_first+src_len+MAX_CMP_GROUP-1].*/
+/* Output : Upon completion guaranteed *p_dst_len<=src_len+FLAG_BYTES.        */
+LOCAL void compress_compress(UBYTE *p_wrk_mem,
+			     UBYTE *p_src_first, ULONG  src_len,
+			     UBYTE *p_dst_first, LONG  *p_dst_len)
+{
+ /* p_src and p_dst step through the source and destination blocks.           */
+ register UBYTE *p_src = p_src_first;
+ register UBYTE *p_dst = p_dst_first;
+ 
+ /* The following variables are never modified and are used in the            */
+ /* calculations that determine when the main loop terminates.                */
+ UBYTE *p_src_post  = p_src_first+src_len;
+ UBYTE *p_dst_post  = p_dst_first+src_len;
+ UBYTE *p_src_max1  = p_src_first+src_len-MAX_RAW_ITEM;
+ UBYTE *p_src_max16 = p_src_first+src_len-MAX_RAW_ITEM*16;
+ 
+ /* The variables 'p_control' and 'control' are used to buffer control bits.  */
+ /* Before each group is processed, the next two bytes of the output block    */
+ /* are set aside for the control word for the group about to be processed.   */
+ /* 'p_control' is set to point to the first byte of that word. Meanwhile,    */
+ /* 'control' buffers the control bits being generated during the processing  */
+ /* of the group. Instead of having a counter to keep track of how many items */
+ /* have been processed (=the number of bits in the control word), at the     */
+ /* start of each group, the top word of 'control' is filled with 1 bits.     */
+ /* As 'control' is shifted for each item, the 1 bits in the top word are     */
+ /* absorbed or destroyed. When they all run out (i.e. when the top word is   */
+ /* all zero bits, we know that we are at the end of a group.                 */
+# define TOPWORD 0xFFFF0000
+ UBYTE *p_control;
+ register ULONG control=TOPWORD;
+ 
+ /* THe variable 'hash' always points to the first element of the hash table. */
+ UBYTE **hash= (UBYTE **)  ULONG_ALIGN_UP(p_wrk_mem);
+ 
+ /* The following two variables represent the literal buffer. p_h1 points to  */
+ /* the hash table entry corresponding to the youngest literal. p_h2 points   */
+ /* to the hash table entry corresponding to the second youngest literal.     */
+ /* Note: p_h1=0=>p_h2=0 because zero values denote absence of a pending      */
+ /* literal. The variables are initialized to zero meaning an empty "buffer". */
+ UBYTE **p_h1=NULL;
+ UBYTE **p_h2=NULL;
+  
+ /* To start, we write the flag bytes. Being optimistic, we set the flag to   */
+ /* FLAG_COMPRESS. The remaining flag bytes are zeroed so as to keep the      */
+ /* algorithm deterministic.                                                  */
+ *p_dst++=FLAG_COMPRESS;
+ {UWORD i; for (i=2;i<=FLAG_BYTES;i++) *p_dst++=0;}
+
+ /* Reserve the first word of output as the control word for the first group. */
+ /* Note: This is undone at the end if the input block is empty.              */
+ p_control=p_dst; p_dst+=2;
+ 
+ /* Initialize all elements of the hash table to point to a constant string.  */
+ /* Use of an unrolled loop speeds this up considerably.                      */
+ {UWORD i; UBYTE **p_h=hash;
+#  define ZH *p_h++=START_STRING_18
+  for (i=0;i<256;i++)     /* 256=HASH_TABLE_LENGTH/16. */
+    {ZH;ZH;ZH;ZH;
+     ZH;ZH;ZH;ZH;
+     ZH;ZH;ZH;ZH;
+     ZH;ZH;ZH;ZH;}
+ }
+
+ /* The main loop processes either 1 or 16 items per iteration. As its        */
+ /* termination logic is complicated, I have opted for an infinite loop       */
+ /* structure containing 'break' and 'goto' statements.                       */
+ while (TRUE)
+   {/* Begin main processing loop. */
+   
+    /* Note: All the variables here except unroll should be defined within    */
+    /*       the inner loop. Unfortunately the loop hasn't got a block.       */
+     register UBYTE *p;         /* Scans through targ phrase during matching. */
+     register UBYTE *p_ziv= NULL ;     /* Points to first byte of current Ziv.       */
+     register UWORD unroll;     /* Loop counter for unrolled inner loop.      */
+     register UWORD index;      /* Index of current hash table entry.         */
+     register UBYTE **p_h0 = NULL ;     /* Pointer to current hash table entry.       */
+     
+    /* Test for overrun and jump to overrun code if necessary.                */
+    if (p_dst>p_dst_post)
+       goto overrun;
+       
+    /* The following cascade of if statements efficiently catches and deals   */
+    /* with varying degrees of closeness to the end of the input block.       */
+    /* When we get very close to the end, we stop updating the table and      */
+    /* code the remaining bytes as literals. This makes the code simpler.     */
+    unroll=16;
+    if (p_src>p_src_max16)
+      {
+       unroll=1;
+       if (p_src>p_src_max1)
+         {
+          if (p_src==p_src_post)
+             break;
+          else
+             goto literal;
+         }
+      }
+         
+    /* This inner unrolled loop processes 'unroll' (whose value is either 1   */
+    /* or 16) items. I have chosen to implement this loop with labels and     */
+    /* gotos to heighten the ease with which the loop may be implemented with */
+    /* a single decrement and branch instruction in assembly language and     */
+    /* also because the labels act as highly readable place markers.          */
+    /* (Also because we jump into the loop for endgame literals (see above)). */
+    
+    begin_unrolled_loop:
+    
+       /* To process the next phrase, we hash the next three bytes and use    */
+       /* the resultant hash table index to look up the hash table. A pointer */
+       /* to the entry is stored in p_h0 so as to avoid an array lookup. The  */
+       /* hash table entry *p_h0 is looked up yielding a pointer p to a       */
+       /* potential match of the Ziv in the history.                          */
+       index=HASH(p_src);
+       p_h0=&hash[index];
+       p=*p_h0;
+       
+       /* Having looked up the candidate position, we are in a position to    */
+       /* attempt a match. The match loop has been unrolled using the PS      */
+       /* macro so that failure within the first three bytes automatically    */
+       /* results in the literal branch being taken. The coding is simple.    */
+       /* p_ziv saves p_src so we can let p_src wander.                       */
+#       define PS *p++!=*p_src++
+       p_ziv=p_src;
+       if (PS || PS || PS)
+         {
+          /* Literal. */
+          
+          /* Code the literal byte as itself and a zero control bit.          */
+          p_src=p_ziv; literal: *p_dst++=*p_src++; control&=0xFFFEFFFF;
+          
+          /* We have just coded a literal. If we had two pending ones, that   */
+          /* makes three and we can update the hash table.                    */
+          if (p_h2!=0)
+             {*p_h2=p_ziv-2;}
+             
+          /* In any case, rotate the hash table pointers for next time. */
+          p_h2=p_h1; p_h1=p_h0;
+          
+         }
+       else
+         {
+          /* Copy */
+          
+          /* Match up to 15 remaining bytes using an unrolled loop and code. */
+#if 0
+          PS || PS || PS || PS || PS || PS || PS || PS ||
+          PS || PS || PS || PS || PS || PS || PS || p_src++;
+#else     
+          if (
+               !( PS || PS || PS || PS || PS || PS || PS || PS ||
+                  PS || PS || PS || PS || PS || PS || PS ) 
+             ) p_src++;
+#endif
+          *p_dst++=((index&0xF00)>>4)|(--p_src-p_ziv-3);
+          *p_dst++=index&0xFF;
+          
+          /* As we have just coded three bytes, we are now in a position to   */
+          /* update the hash table with the literal bytes that were pending   */
+          /* upon the arrival of extra context bytes.                         */
+          if (p_h1!=0)
+            {
+             if (p_h2)
+               {*p_h2=p_ziv-2; p_h2=NULL;}
+             *p_h1=p_ziv-1; p_h1=NULL;
+            }
+            
+          /* In any case, we can update the hash table based on the current   */
+          /* position as we just coded at least three bytes in a copy items.  */
+          *p_h0=p_ziv;
+          
+         }
+       control>>=1;
+                
+       /* This loop is all set up for a decrement and jump instruction! */
+#ifndef linux
+`    end_unrolled_loop: if (--unroll) goto begin_unrolled_loop;
+#else
+    /* end_unrolled_loop: */ if (--unroll) goto begin_unrolled_loop;
+#endif
+
+    /* At this point it will nearly always be the end of a group in which     */
+    /* case, we have to do some control-word processing. However, near the    */
+    /* end of the input block, the inner unrolled loop is only executed once. */
+    /* This necessitates the 'if' test.                                       */
+    if ((control&TOPWORD)==0)
+      {
+       /* Write the control word to the place we saved for it in the output. */
+       *p_control++=  control     &0xFF;
+       *p_control  = (control>>8) &0xFF;
+
+       /* Reserve the next word in the output block for the control word */
+       /* for the group about to be processed.                           */
+       p_control=p_dst; p_dst+=2;
+       
+       /* Reset the control bits buffer. */
+       control=TOPWORD;
+      }
+          
+   } /* End main processing loop. */
+   
+ /* After the main processing loop has executed, all the input bytes have     */
+ /* been processed. However, the control word has still to be written to the  */
+ /* word reserved for it in the output at the start of the most recent group. */
+ /* Before writing, the control word has to be shifted so that all the bits   */
+ /* are in the right place. The "empty" bit positions are filled with 1s      */
+ /* which partially fill the top word.                                        */
+ while(control&TOPWORD) control>>=1;
+ *p_control++= control     &0xFF;
+ *p_control++=(control>>8) &0xFF;
+ 
+ /* If the last group contained no items, delete the control word too.        */
+ if (p_control==p_dst) p_dst-=2;
+ 
+ /* Write the length of the output block to the dst_len parameter and return. */
+ *p_dst_len=p_dst-p_dst_first;                           
+ return;
+ 
+ /* Jump here as soon as an overrun is detected. An overrun is defined to     */
+ /* have occurred if p_dst>p_dst_first+src_len. That is, the moment the       */
+ /* length of the output written so far exceeds the length of the input block.*/
+ /* The algorithm checks for overruns at least at the end of each group       */
+ /* which means that the maximum overrun is MAX_CMP_GROUP bytes.              */
+ /* Once an overrun occurs, the only thing to do is to set the copy flag and  */
+ /* copy the input over.                                                      */
+ overrun:
+#if 0
+ *p_dst_first=FLAG_COPY;
+ fast_copy(p_src_first,p_dst_first+FLAG_BYTES,src_len);
+ *p_dst_len=src_len+FLAG_BYTES;
+#else
+ fast_copy(p_src_first,p_dst_first,src_len);
+ *p_dst_len= -src_len; /* return a negative number to indicate uncompressed data */
+#endif
+}
+
+/******************************************************************************/
+
+/* Input  : Hand over the required amount of working memory in p_wrk_mem.     */
+/* Input  : Specify input block using p_src_first and src_len.                */
+/* Input  : Point p_dst_first to the start of the output zone.                */
+/* Input  : Point p_dst_len to a ULONG to receive the output length.          */
+/* Input  : Input block and output zone must not overlap. User knows          */
+/* Input  : upperbound on output block length from earlier compression.       */
+/* Input  : In any case, maximum expansion possible is nine times.            */
+/* Output : Length of output block written to *p_dst_len.                     */
+/* Output : Output block in Mem[p_dst_first..p_dst_first+*p_dst_len-1].       */
+/* Output : Writes only  in Mem[p_dst_first..p_dst_first+*p_dst_len-1].       */
+LOCAL void compress_decompress( UBYTE *p_wrk_mem,
+				UBYTE *p_src_first, LONG   src_len,
+				UBYTE *p_dst_first, ULONG *p_dst_len)
+{
+ /* Byte pointers p_src and p_dst scan through the input and output blocks.   */
+ register UBYTE *p_src = p_src_first+FLAG_BYTES;
+ register UBYTE *p_dst = p_dst_first;
+ /* we need to avoid a SEGV when trying to uncompress corrupt data */
+ register UBYTE *p_dst_post = p_dst_first + *p_dst_len;
+
+ /* The following two variables are never modified and are used to control    */
+ /* the main loop.                                                            */
+ UBYTE *p_src_post  = p_src_first+src_len;
+ UBYTE *p_src_max16 = p_src_first+src_len-(MAX_CMP_GROUP-2);
+ 
+ /* The hash table is the only resident of the working memory. The hash table */
+ /* contains HASH_TABLE_LENGTH=4096 pointers to positions in the history. To  */
+ /* keep Macintoshes happy, it is longword aligned.                           */
+ UBYTE **hash = (UBYTE **) ULONG_ALIGN_UP(p_wrk_mem);
+
+ /* The variable 'control' is used to buffer the control bits which appear in */
+ /* groups of 16 bits (control words) at the start of each compressed group.  */
+ /* When each group is read, bit 16 of the register is set to one. Whenever   */
+ /* a new bit is needed, the register is shifted right. When the value of the */
+ /* register becomes 1, we know that we have reached the end of a group.      */
+ /* Initializing the register to 1 thus instructs the code to follow that it  */
+ /* should read a new control word immediately.                               */
+ register ULONG control=1;
+ 
+ /* The value of 'literals' is always in the range 0..3. It is the number of  */
+ /* consecutive literal items just seen. We have to record this number so as  */
+ /* to know when to update the hash table. When literals gets to 3, there     */
+ /* have been three consecutive literals and we can update at the position of */
+ /* the oldest of the three.                                                  */
+ register UWORD literals=0;
+ 
+ /* Check the leading copy flag to see if the compressor chose to use a copy  */
+ /* operation instead of a compression operation. If a copy operation was     */
+ /* used, then all we need to do is copy the data over, set the output length */
+ /* and return.                                                               */
+#if 0
+ if (*p_src_first==FLAG_COPY)
+   {
+    fast_copy(p_src_first+FLAG_BYTES,p_dst_first,src_len-FLAG_BYTES);
+    *p_dst_len=src_len-FLAG_BYTES;
+    return;
+   }
+#else
+  if ( src_len < 0 )
+  {                                            
+   fast_copy(p_src_first,p_dst_first,-src_len );
+   *p_dst_len = (ULONG)-src_len;
+   return;
+  }
+#endif
+   
+ /* Initialize all elements of the hash table to point to a constant string.  */
+ /* Use of an unrolled loop speeds this up considerably.                      */
+ {UWORD i; UBYTE **p_h=hash;
+#  define ZJ *p_h++=START_STRING_18
+  for (i=0;i<256;i++)     /* 256=HASH_TABLE_LENGTH/16. */
+    {ZJ;ZJ;ZJ;ZJ;
+     ZJ;ZJ;ZJ;ZJ;
+     ZJ;ZJ;ZJ;ZJ;
+     ZJ;ZJ;ZJ;ZJ;}
+ }
+
+ /* The outer loop processes either 1 or 16 items per iteration depending on  */
+ /* how close p_src is to the end of the input block.                         */
+ while (p_src!=p_src_post)
+   {/* Start of outer loop */
+   
+    register UWORD unroll;   /* Counts unrolled loop executions.              */
+    
+    /* When 'control' has the value 1, it means that the 16 buffered control  */
+    /* bits that were read in at the start of the current group have all been */
+    /* shifted out and that all that is left is the 1 bit that was injected   */
+    /* into bit 16 at the start of the current group. When we reach the end   */
+    /* of a group, we have to load a new control word and inject a new 1 bit. */
+    if (control==1)
+      {
+       control=0x10000|*p_src++;
+       control|=(*p_src++)<<8;
+      }
+
+    /* If it is possible that we are within 16 groups from the end of the     */
+    /* input, execute the unrolled loop only once, else process a whole group */
+    /* of 16 items by looping 16 times.                                       */
+    unroll= p_src<=p_src_max16 ? 16 : 1;
+
+    /* This inner loop processes one phrase (item) per iteration. */
+    while (unroll--)
+      { /* Begin unrolled inner loop. */
+      
+       /* Process a literal or copy item depending on the next control bit. */
+       if (control&1)
+         {
+          /* Copy item. */
+          
+          register UBYTE *p;           /* Points to place from which to copy. */
+          register UWORD lenmt;        /* Length of copy item minus three.    */
+          register UBYTE **p_hte;      /* Pointer to current hash table entry.*/
+          register UBYTE *p_ziv=p_dst; /* Pointer to start of current Ziv.    */
+          
+          /* Read and dismantle the copy word. Work out from where to copy.   */
+          lenmt=*p_src++;
+          p_hte=&hash[((lenmt&0xF0)<<4)|*p_src++];
+          p=*p_hte;
+          lenmt&=0xF;
+          
+          /* Now perform the copy using a half unrolled loop. */
+          *p_dst++=*p++;
+          *p_dst++=*p++;
+          *p_dst++=*p++;
+          while (lenmt--)
+             *p_dst++=*p++;
+                 
+          /* Because we have just received 3 or more bytes in a copy item     */
+          /* (whose bytes we have just installed in the output), we are now   */
+          /* in a position to flush all the pending literal hashings that had */
+          /* been postponed for lack of bytes.                                */
+          if (literals>0)
+            {
+             register UBYTE *r=p_ziv-literals;
+             hash[HASH(r)]=r;
+             if (literals==2)
+                {r++; hash[HASH(r)]=r;}
+             literals=0;
+            }
+            
+          /* In any case, we can immediately update the hash table with the   */
+          /* current position. We don't need to do a HASH(...) to work out    */
+          /* where to put the pointer, as the compressor just told us!!!      */
+          *p_hte=p_ziv;
+          
+         }
+       else
+         {
+          /* Literal item. */
+          
+          /* Copy over the literal byte. */
+          *p_dst++=*p_src++;
+          
+          /* If we now have three literals waiting to be hashed into the hash */
+          /* table, we can do one of them now (because there are three).      */
+          if (++literals == 3)
+             {register UBYTE *p=p_dst-3; hash[HASH(p)]=p; literals=2;}
+         }
+          
+       /* Shift the control buffer so the next control bit is in bit 0. */
+       control>>=1;
+#if 1
+       if (p_dst > p_dst_post) 
+       {
+	       /* Shit: we tried to decompress corrupt data */
+	       *p_dst_len = 0;
+	       return;
+       }
+#endif
+      } /* End unrolled inner loop. */
+               
+   } /* End of outer loop */
+   
+ /* Write the length of the decompressed data before returning. */
+  *p_dst_len=p_dst-p_dst_first;
+}
+
+/******************************************************************************/
+/*                               End of LZRW3.C                               */
+/******************************************************************************/
diff --git a/drivers/char/ftape/compressor/lzrw3.h b/drivers/char/ftape/compressor/lzrw3.h
new file mode 100644
index 0000000..533feba
--- /dev/null
+++ b/drivers/char/ftape/compressor/lzrw3.h
@@ -0,0 +1,253 @@
+#ifndef _LZRW3_H
+#define _LZRW3_H
+/*
+ * $Source: /homes/cvs/ftape-stacked/ftape/compressor/lzrw3.h,v $
+ * $Revision: 1.1 $
+ * $Date: 1997/10/05 19:12:30 $
+ *
+ *  include files for lzrw3. Only slighty modified from the original
+ *  version. Assembles the three include files compress.h, port.h and
+ *  fastcopy.h from the original lzrw3 package.
+ *
+ */
+
+#include <linux/types.h>
+#include <linux/string.h>
+
+/******************************************************************************/
+/*                                                                            */
+/*                                 COMPRESS.H                                 */
+/*                                                                            */
+/******************************************************************************/
+/*                                                                            */
+/* Author : Ross Williams.                                                    */
+/* Date   : December 1989.                                                    */
+/*                                                                            */
+/* This header file defines the interface to a set of functions called        */
+/* 'compress', each member of which implements a particular data compression  */
+/* algorithm.                                                                 */
+/*                                                                            */
+/* Normally in C programming, for each .H file, there is a corresponding .C   */
+/* file that implements the functions promised in the .H file.                */
+/* Here, there are many .C files corresponding to this header file.           */
+/* Each comforming implementation file contains a single function             */
+/* called 'compress' that implements a single data compression                */
+/* algorithm that conforms with the interface specified in this header file.  */
+/* Only one algorithm can be linked in at a time in this organization.        */
+/*                                                                            */
+/******************************************************************************/
+/*                                                                            */
+/*                    DEFINITION OF FUNCTION COMPRESS                         */
+/*                    ===============================                         */
+/*                                                                            */
+/* Summary of Function Compress                                               */
+/* ----------------------------                                               */
+/* The action that 'compress' takes depends on its first argument called      */
+/* 'action'.  The function provides three actions:                            */
+/*                                                                            */
+/*    - Return information about the algorithm.                               */
+/*    - Compress   a block of memory.                                         */
+/*    - Decompress a block of memory.                                         */
+/*                                                                            */
+/* Parameters                                                                 */
+/* ----------                                                                 */
+/* See the formal C definition later for a description of the parameters.     */
+/*                                                                            */
+/* Constants                                                                  */
+/* ---------                                                                  */
+/* COMPRESS_OVERRUN: The constant COMPRESS_OVERRUN defines by how many bytes  */
+/* an algorithm is allowed to expand a block during a compression operation.  */
+/*                                                                            */
+/* Although compression algorithms usually compress data, there will always   */
+/* be data that a given compressor will expand (this can be proven).          */
+/* Fortunately, the degree of expansion can be limited to a single bit, by    */
+/* copying over the input data if the data gets bigger during compression.    */
+/* To allow for this possibility, the first bit of a compressed               */
+/* representation can be used as a flag indicating whether the                */
+/* input data was copied over, or truly compressed. In practice, the first    */
+/* byte would be used to store this bit so as to maintain byte alignment.     */
+/*                                                                            */
+/* Unfortunately, in general, the only way to tell if an algorithm will       */
+/* expand a particular block of data is to run the algorithm on the data.     */
+/* If the algorithm does not continuously monitor how many output bytes it    */
+/* has written, it might write an output block far larger than the input      */
+/* block before realizing that it has done so.                                */
+/* On the other hand, continuous checks on output length are inefficient.     */
+/*                                                                            */
+/* To cater for all these problems, this interface definition:                */
+/* > Allows a compression algorithm to return an output block that is up to   */
+/*   COMPRESS_OVERRUN bytes longer than the input block.                      */
+/* > Allows a compression algorithm to write up to COMPRESS_OVERRUN bytes     */
+/*   more than the length of the input block to the memory of the output      */
+/*   block regardless of the length of the output block eventually returned.  */
+/*   This allows an algorithm to overrun the length of the input block in the */
+/*   output block by up to COMPRESS_OVERRUN bytes between expansion checks.   */
+/*                                                                            */
+/* The problem does not arise for decompression.                              */
+/*                                                                            */
+/* Identity Action                                                            */
+/* ---------------                                                            */
+/* > action must be COMPRESS_ACTION_IDENTITY.                                 */
+/* > p_dst_len must point to a longword to receive a longword address.        */
+/* > The value of the other parameters does not matter.                       */
+/* > After execution, the longword that p_dst_len points to will be a pointer */
+/*   to a structure of type compress_identity.                                */
+/*   Thus, for example, after the call, (*p_dst_len)->memory will return the  */
+/*   number of bytes of working memory that the algorithm requires to run.    */
+/* > The values of the identity structure returned are fixed constant         */
+/*   attributes of the algorithm and must not vary from call to call.         */
+/*                                                                            */
+/* Common Requirements for Compression and Decompression Actions              */
+/* -------------------------------------------------------------              */
+/* > wrk_mem must point to an unused block of memory of a length specified in */
+/*   the algorithm's identity block. The identity block can be obtained by    */
+/*   making a separate call to compress, specifying the identity action.      */
+/* > The INPUT BLOCK is defined to be Memory[src_addr,src_addr+src_len-1].    */
+/* > dst_len will be used to denote *p_dst_len.                               */
+/* > dst_len is not read by compress, only written.                           */
+/* > The value of dst_len is defined only upon termination.                   */
+/* > The OUTPUT BLOCK is defined to be Memory[dst_addr,dst_addr+dst_len-1].   */
+/*                                                                            */
+/* Compression Action                                                         */
+/* ------------------                                                         */
+/* > action must be COMPRESS_ACTION_COMPRESS.                                 */
+/* > src_len must be in the range [0,COMPRESS_MAX_ORG].                       */
+/* > The OUTPUT ZONE is defined to be                                         */
+/*      Memory[dst_addr,dst_addr+src_len-1+COMPRESS_OVERRUN].                 */
+/* > The function can modify any part of the output zone regardless of the    */
+/*   final length of the output block.                                        */
+/* > The input block and the output zone must not overlap.                    */
+/* > dst_len will be in the range [0,src_len+COMPRESS_OVERRUN].               */
+/* > dst_len will be in the range [0,COMPRESS_MAX_COM] (from prev fact).      */
+/* > The output block will consist of a representation of the input block.    */
+/*                                                                            */
+/* Decompression Action                                                       */
+/* --------------------                                                       */
+/* > action must be COMPRESS_ACTION_DECOMPRESS.                               */
+/* > The input block must be the result of an earlier compression operation.  */
+/* > If the previous fact is true, the following facts must also be true:     */
+/*   > src_len will be in the range [0,COMPRESS_MAX_COM].                     */
+/*   > dst_len will be in the range [0,COMPRESS_MAX_ORG].                     */
+/* > The input and output blocks must not overlap.                            */
+/* > Only the output block is modified.                                       */
+/* > Upon termination, the output block will consist of the bytes contained   */
+/*   in the input block passed to the earlier compression operation.          */
+/*                                                                            */
+/******************************************************************************/
+
+/******************************************************************************/
+/*                                                                            */
+/*                                    PORT.H                                  */
+/*                                                                            */
+/******************************************************************************/
+/*                                                                            */
+/* This module contains macro definitions and types that are likely to        */
+/* change between computers.                                                  */
+/*                                                                            */
+/******************************************************************************/
+
+#ifndef DONE_PORT       /* Only do this if not previously done.               */
+
+   #ifdef THINK_C
+      #define UBYTE unsigned char      /* Unsigned byte                       */
+      #define UWORD unsigned int       /* Unsigned word (2 bytes)             */
+      #define ULONG unsigned long      /* Unsigned word (4 bytes)             */
+      #define BOOL  unsigned char      /* Boolean                             */
+      #define FOPEN_BINARY_READ  "rb"  /* Mode string for binary reading.     */
+      #define FOPEN_BINARY_WRITE "wb"  /* Mode string for binary writing.     */
+      #define FOPEN_TEXT_APPEND  "a"   /* Mode string for text appending.     */
+      #define REAL double              /* USed for floating point stuff.      */
+   #endif
+   #if defined(LINUX) || defined(linux)
+      #define UBYTE __u8               /* Unsigned byte                       */
+      #define UWORD __u16              /* Unsigned word (2 bytes)             */
+      #define ULONG __u32              /* Unsigned word (4 bytes)             */
+      #define LONG  __s32              /* Signed   word (4 bytes)             */
+      #define BOOL  is not used here   /* Boolean                             */
+      #define FOPEN_BINARY_READ  not used  /* Mode string for binary reading. */
+      #define FOPEN_BINARY_WRITE not used  /* Mode string for binary writing. */
+      #define FOPEN_TEXT_APPEND  not used  /* Mode string for text appending. */
+      #define REAL not used                /* USed for floating point stuff.  */
+      #ifndef TRUE
+      #define TRUE 1
+      #endif
+   #endif
+
+   #define DONE_PORT                   /* Don't do all this again.            */
+   #define MALLOC_FAIL NULL            /* Failure status from malloc()        */
+   #define LOCAL static                /* For non-exported routines.          */
+   #define EXPORT                      /* Signals exported function.          */
+   #define then                        /* Useful for aligning ifs.            */
+
+#endif
+
+/******************************************************************************/
+/*                              End of PORT.H                                 */
+/******************************************************************************/
+
+#define COMPRESS_ACTION_IDENTITY   0
+#define COMPRESS_ACTION_COMPRESS   1
+#define COMPRESS_ACTION_DECOMPRESS 2
+
+#define COMPRESS_OVERRUN 1024
+#define COMPRESS_MAX_COM 0x70000000
+#define COMPRESS_MAX_ORG (COMPRESS_MAX_COM-COMPRESS_OVERRUN)
+
+#define COMPRESS_MAX_STRLEN 255
+
+/* The following structure provides information about the algorithm.         */
+/* > The top bit of id must be zero. The remaining bits must be chosen by    */
+/*   the author of the algorithm by tossing a coin 31 times.                 */
+/* > The amount of memory requested by the algorithm is specified in bytes   */
+/*   and must be in the range [0,0x70000000].                                */
+/* > All strings s must be such that strlen(s)<=COMPRESS_MAX_STRLEN.         */
+struct compress_identity
+  {
+   ULONG id;           /* Identifying number of algorithm.            */
+   ULONG memory;       /* Number of bytes of working memory required. */
+
+   char  *name;        /* Name of algorithm.                          */
+   char  *version;     /* Version number.                             */
+   char  *date;        /* Date of release of this version.            */
+   char  *copyright;   /* Copyright message.                          */
+
+   char  *author;      /* Author of algorithm.                        */
+   char  *affiliation; /* Affiliation of author.                      */
+   char  *vendor;      /* Where the algorithm can be obtained.        */
+  };
+
+void  lzrw3_compress(        /* Single function interface to compression algorithm. */
+UWORD     action,      /* Action to be performed.                             */
+UBYTE   *wrk_mem,      /* Working memory temporarily given to routine to use. */
+UBYTE   *src_adr,      /* Address of input  data.                             */
+LONG     src_len,      /* Length  of input  data.                             */
+UBYTE   *dst_adr,      /* Address of output data.                             */
+void  *p_dst_len       /* Pointer to a longword where routine will write:     */
+                       /*    If action=..IDENTITY   => Adr of id structure.   */
+                       /*    If action=..COMPRESS   => Length of output data. */
+                       /*    If action=..DECOMPRESS => Length of output data. */
+);
+
+/******************************************************************************/
+/*                             End of COMPRESS.H                              */
+/******************************************************************************/
+
+
+/******************************************************************************/
+/*                                  fast_copy.h                               */
+/******************************************************************************/
+
+/* This function copies a block of memory very quickly.                       */
+/* The exact speed depends on the relative alignment of the blocks of memory. */
+/* PRE  : 0<=src_len<=(2^32)-1 .                                              */
+/* PRE  : Source and destination blocks must not overlap.                     */
+/* POST : MEM[dst_adr,dst_adr+src_len-1]=MEM[src_adr,src_adr+src_len-1].      */
+/* POST : MEM[dst_adr,dst_adr+src_len-1] is the only memory changed.          */
+
+#define fast_copy(src,dst,len) memcpy(dst,src,len)
+
+/******************************************************************************/
+/*                               End of fast_copy.h                           */
+/******************************************************************************/
+
+#endif
diff --git a/drivers/char/ftape/compressor/zftape-compress.c b/drivers/char/ftape/compressor/zftape-compress.c
new file mode 100644
index 0000000..220a227
--- /dev/null
+++ b/drivers/char/ftape/compressor/zftape-compress.c
@@ -0,0 +1,1203 @@
+/*
+ *      Copyright (C) 1994-1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2, or (at
+ your option) any later version.
+ 
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+ 
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ USA.
+ 
+ *
+ *     This file implements a "generic" interface between the *
+ *     zftape-driver and a compression-algorithm. The *
+ *     compression-algorithm currently used is a LZ77. I use the *
+ *     implementation lzrw3 by Ross N. Williams (Renaissance *
+ *     Software). The compression program itself is in the file
+ *     lzrw3.c * and lzrw3.h.  To adopt another compression algorithm
+ *     the functions * zft_compress() and zft_uncompress() must be
+ *     changed * appropriately. See below.
+ */
+
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+
+#include <linux/zftape.h>
+
+#include <asm/uaccess.h>
+
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-eof.h"
+#include "../zftape/zftape-ctl.h"
+#include "../zftape/zftape-write.h"
+#include "../zftape/zftape-read.h"
+#include "../zftape/zftape-rw.h"
+#include "../compressor/zftape-compress.h"
+#include "../zftape/zftape-vtbl.h"
+#include "../compressor/lzrw3.h"
+
+/*
+ *   global variables
+ */
+
+/* I handle the allocation of this buffer as a special case, because
+ * it's size varies depending on the tape length inserted.
+ */
+
+/* local variables 
+ */
+static void *zftc_wrk_mem = NULL;
+static __u8 *zftc_buf     = NULL;
+static void *zftc_scratch_buf  = NULL;
+
+/* compression statistics 
+ */
+static unsigned int zftc_wr_uncompressed = 0;
+static unsigned int zftc_wr_compressed   = 0;
+static unsigned int zftc_rd_uncompressed = 0;
+static unsigned int zftc_rd_compressed   = 0;
+
+/* forward */
+static int  zftc_write(int *write_cnt,
+		       __u8 *dst_buf, const int seg_sz,
+		       const __u8 __user *src_buf, const int req_len,
+		       const zft_position *pos, const zft_volinfo *volume);
+static int  zftc_read(int *read_cnt,
+		      __u8  __user *dst_buf, const int to_do,
+		      const __u8 *src_buf, const int seg_sz,
+		      const zft_position *pos, const zft_volinfo *volume);
+static int  zftc_seek(unsigned int new_block_pos, 
+		      zft_position *pos, const zft_volinfo *volume,
+		      __u8 *buffer);
+static void zftc_lock   (void);
+static void zftc_reset  (void);
+static void zftc_cleanup(void);
+static void zftc_stats      (void);
+
+/* compressed segment. This conforms to QIC-80-MC, Revision K.
+ * 
+ * Rev. K applies to tapes with `fixed length format' which is
+ * indicated by format code 2,3 and 5. See below for format code 4 and 6
+ *
+ * 2 bytes: offset of compression segment structure
+ *          29k > offset >= 29k-18: data from previous segment ens in this
+ *                                  segment and no compressed block starts
+ *                                  in this segment
+ *                     offset == 0: data from previous segment occupies entire
+ *                                  segment and continues in next segment
+ * n bytes: remainder from previous segment
+ * 
+ * Rev. K:  
+ * 4 bytes: 4 bytes: files set byte offset
+ * Post Rev. K and QIC-3020/3020:
+ * 8 bytes: 8 bytes: files set byte offset
+ * 2 bytes: byte count N (amount of data following)
+ *          bit 15 is set if data is compressed, bit 15 is not
+ *          set if data is uncompressed
+ * N bytes: data (as much as specified in the byte count)
+ * 2 bytes: byte count N_1 of next cluster
+ * N_1 bytes: data of next cluset
+ * 2 bytes: byte count N_2 of next cluster
+ * N_2 bytes: ...  
+ *
+ * Note that the `N' byte count accounts only for the bytes that in the
+ * current segment if the cluster spans to the next segment.
+ */
+
+typedef struct
+{
+	int cmpr_pos;             /* actual position in compression buffer */
+	int cmpr_sz;              /* what is left in the compression buffer
+				   * when copying the compressed data to the
+				   * deblock buffer
+				   */
+	unsigned int first_block; /* location of header information in
+				   * this segment
+				   */
+	unsigned int count;       /* amount of data of current block
+				   * contained in current segment 
+				   */
+	unsigned int offset;      /* offset in current segment */
+	unsigned int spans:1;     /* might continue in next segment */
+	unsigned int uncmpr;      /* 0x8000 if this block contains
+				   * uncompressed data 
+				   */
+	__s64 foffs;              /* file set byte offset, same as in 
+				   * compression map segment
+				   */
+} cmpr_info;
+
+static cmpr_info cseg; /* static data. Must be kept uptodate and shared by 
+			* read, write and seek functions
+			*/
+
+#define DUMP_CMPR_INFO(level, msg, info)				\
+	TRACE(level, msg "\n"						\
+	      KERN_INFO "cmpr_pos   : %d\n"				\
+	      KERN_INFO "cmpr_sz    : %d\n"				\
+	      KERN_INFO "first_block: %d\n"				\
+	      KERN_INFO "count      : %d\n"				\
+	      KERN_INFO "offset     : %d\n"				\
+	      KERN_INFO "spans      : %d\n"				\
+	      KERN_INFO "uncmpr     : 0x%04x\n"				\
+	      KERN_INFO "foffs      : " LL_X,				\
+	      (info)->cmpr_pos, (info)->cmpr_sz, (info)->first_block,	\
+	      (info)->count, (info)->offset, (info)->spans == 1,	\
+	      (info)->uncmpr, LL((info)->foffs))
+
+/*   dispatch compression segment info, return error code
+ *  
+ *   afterwards, cseg->offset points to start of data of the NEXT
+ *   compressed block, and cseg->count contains the amount of data
+ *   left in the actual compressed block. cseg->spans is set to 1 if
+ *   the block is continued in the following segment. Otherwise it is
+ *   set to 0. 
+ */
+static int get_cseg (cmpr_info *cinfo, const __u8 *buff, 
+		     const unsigned int seg_sz,
+		     const zft_volinfo *volume)
+{
+	TRACE_FUN(ft_t_flow);
+
+ 	cinfo->first_block = GET2(buff, 0);
+	if (cinfo->first_block == 0) { /* data spans to next segment */
+		cinfo->count  = seg_sz - sizeof(__u16);
+		cinfo->offset = seg_sz;
+		cinfo->spans = 1;
+	} else { /* cluster definetely ends in this segment */
+		if (cinfo->first_block > seg_sz) {
+			/* data corrupted */
+			TRACE_ABORT(-EIO, ft_t_err, "corrupted data:\n"
+				    KERN_INFO "segment size: %d\n"
+				    KERN_INFO "first block : %d",
+				    seg_sz, cinfo->first_block);
+		}
+	        cinfo->count  = cinfo->first_block - sizeof(__u16);
+		cinfo->offset = cinfo->first_block;
+		cinfo->spans = 0;
+	}
+	/* now get the offset the first block should have in the
+	 * uncompressed data stream.
+	 *
+	 * For this magic `18' refer to CRF-3 standard or QIC-80MC,
+	 * Rev. K.  
+	 */
+	if ((seg_sz - cinfo->offset) > 18) {
+		if (volume->qic113) { /* > revision K */
+			TRACE(ft_t_data_flow, "New QIC-113 compliance");
+			cinfo->foffs = GET8(buff, cinfo->offset);
+			cinfo->offset += sizeof(__s64); 
+		} else {
+			TRACE(/* ft_t_data_flow */ ft_t_noise, "pre QIC-113 version");
+			cinfo->foffs   = (__s64)GET4(buff, cinfo->offset);
+			cinfo->offset += sizeof(__u32); 
+		}
+	}
+	if (cinfo->foffs > volume->size) {
+		TRACE_ABORT(-EIO, ft_t_err, "Inconsistency:\n"
+			    KERN_INFO "offset in current volume: %d\n"
+			    KERN_INFO "size of current volume  : %d",
+			    (int)(cinfo->foffs>>10), (int)(volume->size>>10));
+	}
+	if (cinfo->cmpr_pos + cinfo->count > volume->blk_sz) {
+		TRACE_ABORT(-EIO, ft_t_err, "Inconsistency:\n"
+			    KERN_INFO "block size : %d\n"
+			    KERN_INFO "data record: %d",
+			    volume->blk_sz, cinfo->cmpr_pos + cinfo->count);
+	}
+	DUMP_CMPR_INFO(ft_t_noise /* ft_t_any */, "", cinfo);
+	TRACE_EXIT 0;
+}
+
+/*  This one is called, when a new cluster starts in same segment.
+ *  
+ *  Note: if this is the first cluster in the current segment, we must
+ *  not check whether there are more than 18 bytes available because
+ *  this have already been done in get_cseg() and there may be less
+ *  than 18 bytes available due to header information.
+ * 
+ */
+static void get_next_cluster(cmpr_info *cluster, const __u8 *buff, 
+			     const int seg_sz, const int finish)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (seg_sz - cluster->offset > 18 || cluster->foffs != 0) {
+		cluster->count   = GET2(buff, cluster->offset);
+		cluster->uncmpr  = cluster->count & 0x8000;
+		cluster->count  -= cluster->uncmpr;
+		cluster->offset += sizeof(__u16);
+		cluster->foffs   = 0;
+		if ((cluster->offset + cluster->count) < seg_sz) {
+			cluster->spans = 0;
+		} else if (cluster->offset + cluster->count == seg_sz) {
+			cluster->spans = !finish;
+		} else {
+			/* either an error or a volume written by an 
+			 * old version. If this is a data error, then we'll
+			 * catch it later.
+			 */
+			TRACE(ft_t_data_flow, "Either error or old volume");
+			cluster->spans = 1;
+			cluster->count = seg_sz - cluster->offset;
+		}
+	} else {
+		cluster->count = 0;
+		cluster->spans = 0;
+		cluster->foffs = 0;
+	}
+	DUMP_CMPR_INFO(ft_t_noise /* ft_t_any */ , "", cluster);
+	TRACE_EXIT;
+}
+
+static void zftc_lock(void)
+{
+}
+
+/*  this function is needed for zftape_reset_position in zftape-io.c 
+ */
+static void zftc_reset(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	memset((void *)&cseg, '\0', sizeof(cseg));
+	zftc_stats();
+	TRACE_EXIT;
+}
+
+static int cmpr_mem_initialized = 0;
+static unsigned int alloc_blksz = 0;
+
+static int zft_allocate_cmpr_mem(unsigned int blksz)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (cmpr_mem_initialized && blksz == alloc_blksz) {
+		TRACE_EXIT 0;
+	}
+	TRACE_CATCH(zft_vmalloc_once(&zftc_wrk_mem, CMPR_WRK_MEM_SIZE),
+		    zftc_cleanup());
+	TRACE_CATCH(zft_vmalloc_always(&zftc_buf, blksz + CMPR_OVERRUN),
+		    zftc_cleanup());
+	alloc_blksz = blksz;
+	TRACE_CATCH(zft_vmalloc_always(&zftc_scratch_buf, blksz+CMPR_OVERRUN),
+		    zftc_cleanup());
+	cmpr_mem_initialized = 1;
+	TRACE_EXIT 0;
+}
+
+static void zftc_cleanup(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	zft_vfree(&zftc_wrk_mem, CMPR_WRK_MEM_SIZE);
+	zft_vfree(&zftc_buf, alloc_blksz + CMPR_OVERRUN);
+	zft_vfree(&zftc_scratch_buf, alloc_blksz + CMPR_OVERRUN);
+	cmpr_mem_initialized = alloc_blksz = 0;
+	TRACE_EXIT;
+}
+
+/*****************************************************************************
+ *                                                                           *
+ *  The following two functions "ftape_compress()" and                       *
+ *  "ftape_uncompress()" are the interface to the actual compression         *
+ *  algorithm (i.e. they are calling the "compress()" function from          *
+ *  the lzrw3 package for now). These routines could quite easily be         *
+ *  changed to adopt another compression algorithm instead of lzrw3,         *
+ *  which currently is used.                                                 *
+ *                                                                           *
+ *****************************************************************************/
+
+/* called by zft_compress_write() to perform the compression. Must
+ * return the size of the compressed data.
+ *
+ * NOTE: The size of the compressed data should not exceed the size of
+ *       the uncompressed data. Most compression algorithms have means
+ *       to store data unchanged if the "compressed" data amount would
+ *       exceed the original one. Mostly this is done by storing some
+ *       flag-bytes in front of the compressed data to indicate if it
+ *       is compressed or not. Thus the worst compression result
+ *       length is the original length plus those flag-bytes.
+ *
+ *       We don't want that, as the QIC-80 standard provides a means
+ *       of marking uncompressed blocks by simply setting bit 15 of
+ *       the compressed block's length. Thus a compessed block can
+ *       have at most a length of 2^15-1 bytes. The QIC-80 standard
+ *       restricts the block-length even further, allowing only 29k -
+ *       6 bytes.
+ *
+ *       Currently, the maximum blocksize used by zftape is 28k.
+ *
+ *       In short: don't exceed the length of the input-package, set
+ *       bit 15 of the compressed size to 1 if you have copied data
+ *       instead of compressing it.
+ */
+static int zft_compress(__u8 *in_buffer, unsigned int in_sz, __u8 *out_buffer)
+{ 
+	__s32 compressed_sz;
+	TRACE_FUN(ft_t_flow);
+	
+
+	lzrw3_compress(COMPRESS_ACTION_COMPRESS, zftc_wrk_mem,
+		       in_buffer, in_sz, out_buffer, &compressed_sz);
+	if (TRACE_LEVEL >= ft_t_info) {
+		/*  the compiler will optimize this away when
+		 *  compiled with NO_TRACE_AT_ALL option
+		 */
+		TRACE(ft_t_data_flow, "\n"
+		      KERN_INFO "before compression: %d bytes\n"
+		      KERN_INFO "after compresison : %d bytes", 
+		      in_sz, 
+		      (int)(compressed_sz < 0 
+		      ? -compressed_sz : compressed_sz));
+		/*  for statistical purposes
+		 */
+		zftc_wr_compressed   += (compressed_sz < 0 
+					   ? -compressed_sz : compressed_sz);
+		zftc_wr_uncompressed += in_sz;
+	}
+	TRACE_EXIT (int)compressed_sz;
+}
+
+/* called by zft_compress_read() to decompress the data. Must
+ * return the size of the decompressed data for sanity checks
+ * (compared with zft_blk_sz)
+ *
+ * NOTE: Read the note for zft_compress() above!  If bit 15 of the
+ *       parameter in_sz is set, then the data in in_buffer isn't
+ *       compressed, which must be handled by the un-compression
+ *       algorithm. (I changed lzrw3 to handle this.)
+ *
+ *  The parameter max_out_sz is needed to prevent buffer overruns when 
+ *  uncompressing corrupt data.
+ */
+static unsigned int zft_uncompress(__u8 *in_buffer, 
+				   int in_sz, 
+				   __u8 *out_buffer,
+				   unsigned int max_out_sz)
+{ 
+	TRACE_FUN(ft_t_flow);
+	
+	lzrw3_compress(COMPRESS_ACTION_DECOMPRESS, zftc_wrk_mem,
+		       in_buffer, (__s32)in_sz,
+		       out_buffer, (__u32 *)&max_out_sz);
+	
+	if (TRACE_LEVEL >= ft_t_info) {
+		TRACE(ft_t_data_flow, "\n"
+		      KERN_INFO "before decompression: %d bytes\n"
+		      KERN_INFO "after decompression : %d bytes", 
+		      in_sz < 0 ? -in_sz : in_sz,(int)max_out_sz);
+		/*  for statistical purposes
+		 */
+		zftc_rd_compressed   += in_sz < 0 ? -in_sz : in_sz;
+		zftc_rd_uncompressed += max_out_sz;
+	}
+	TRACE_EXIT (unsigned int)max_out_sz;
+}
+
+/* print some statistics about the efficiency of the compression to
+ * the kernel log 
+ */
+static void zftc_stats(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (TRACE_LEVEL < ft_t_info) {
+		TRACE_EXIT;
+	}
+	if (zftc_wr_uncompressed != 0) {
+		if (zftc_wr_compressed > (1<<14)) {
+			TRACE(ft_t_info, "compression statistics (writing):\n"
+			      KERN_INFO " compr./uncmpr.   : %3d %%",
+			      (((zftc_wr_compressed>>10) * 100)
+			       / (zftc_wr_uncompressed>>10)));
+		} else {
+			TRACE(ft_t_info, "compression statistics (writing):\n"
+			      KERN_INFO " compr./uncmpr.   : %3d %%",
+			      ((zftc_wr_compressed * 100)
+			       / zftc_wr_uncompressed));
+		}
+	}
+	if (zftc_rd_uncompressed != 0) {
+		if (zftc_rd_compressed > (1<<14)) {
+			TRACE(ft_t_info, "compression statistics (reading):\n"
+			      KERN_INFO " compr./uncmpr.   : %3d %%",
+			      (((zftc_rd_compressed>>10) * 100)
+			       / (zftc_rd_uncompressed>>10)));
+		} else {
+			TRACE(ft_t_info, "compression statistics (reading):\n"
+			      KERN_INFO " compr./uncmpr.   : %3d %%",
+			      ((zftc_rd_compressed * 100)
+			       / zftc_rd_uncompressed));
+		}
+	}
+	/* only print it once: */
+	zftc_wr_uncompressed = 
+		zftc_wr_compressed  =
+		zftc_rd_uncompressed =
+		zftc_rd_compressed   = 0;
+	TRACE_EXIT;
+}
+
+/* start new compressed block 
+ */
+static int start_new_cseg(cmpr_info *cluster, 
+			  char *dst_buf, 
+			  const zft_position *pos,
+			  const unsigned int blk_sz,
+			  const char *src_buf,
+			  const int this_segs_sz,
+			  const int qic113)
+{
+	int size_left;
+	int cp_cnt;
+	int buf_pos;
+	TRACE_FUN(ft_t_flow);
+
+	size_left = this_segs_sz - sizeof(__u16) - cluster->cmpr_sz;
+	TRACE(ft_t_data_flow,"\n" 
+	      KERN_INFO "segment size   : %d\n"
+	      KERN_INFO "compressed_sz: %d\n"
+	      KERN_INFO "size_left      : %d",
+	      this_segs_sz, cluster->cmpr_sz, size_left);
+	if (size_left > 18) { /* start a new cluseter */
+		cp_cnt = cluster->cmpr_sz;
+		cluster->cmpr_sz = 0;
+		buf_pos = cp_cnt + sizeof(__u16);
+		PUT2(dst_buf, 0, buf_pos);
+
+		if (qic113) {
+			__s64 foffs = pos->volume_pos;
+			if (cp_cnt) foffs += (__s64)blk_sz;
+
+			TRACE(ft_t_data_flow, "new style QIC-113 header");
+			PUT8(dst_buf, buf_pos, foffs);
+			buf_pos += sizeof(__s64);
+		} else {
+			__u32 foffs = (__u32)pos->volume_pos;
+			if (cp_cnt) foffs += (__u32)blk_sz;
+			
+			TRACE(ft_t_data_flow, "old style QIC-80MC header");
+			PUT4(dst_buf, buf_pos, foffs);
+			buf_pos += sizeof(__u32);
+		}
+	} else if (size_left >= 0) {
+		cp_cnt = cluster->cmpr_sz;
+		cluster->cmpr_sz = 0;
+		buf_pos = cp_cnt + sizeof(__u16);
+		PUT2(dst_buf, 0, buf_pos);  
+		/* zero unused part of segment. */
+		memset(dst_buf + buf_pos, '\0', size_left);
+		buf_pos = this_segs_sz;
+	} else { /* need entire segment and more space */
+		PUT2(dst_buf, 0, 0); 
+		cp_cnt = this_segs_sz - sizeof(__u16);
+		cluster->cmpr_sz  -= cp_cnt;
+		buf_pos = this_segs_sz;
+	}
+	memcpy(dst_buf + sizeof(__u16), src_buf + cluster->cmpr_pos, cp_cnt);
+	cluster->cmpr_pos += cp_cnt;
+	TRACE_EXIT buf_pos;
+}
+
+/* return-value: the number of bytes removed from the user-buffer
+ *               `src_buf' or error code
+ *
+ *  int *write_cnt           : how much actually has been moved to the
+ *                             dst_buf. Need not be initialized when
+ *                             function returns with an error code
+ *                             (negativ return value) 
+ *  __u8 *dst_buf            : kernel space buffer where the has to be
+ *                             copied to. The contents of this buffers
+ *                             goes to a specific segment.
+ *  const int seg_sz         : the size of the segment dst_buf will be
+ *                             copied to.
+ *  const zft_position *pos  : struct containing the coordinates in
+ *                             the current volume (byte position,
+ *                             segment id of current segment etc)
+ *  const zft_volinfo *volume: information about the current volume,
+ *                             size etc.
+ *  const __u8 *src_buf      : user space buffer that contains the
+ *                             data the user wants to be written to
+ *                             tape.
+ *  const int req_len        : the amount of data the user wants to be
+ *                             written to tape.
+ */
+static int zftc_write(int *write_cnt,
+		      __u8 *dst_buf, const int seg_sz,
+		      const __u8 __user *src_buf, const int req_len,
+		      const zft_position *pos, const zft_volinfo *volume)
+{
+	int req_len_left = req_len;
+	int result;
+	int len_left;
+	int buf_pos_write = pos->seg_byte_pos;
+	TRACE_FUN(ft_t_flow);
+	
+	/* Note: we do not unlock the module because
+	 * there are some values cached in that `cseg' variable.  We
+	 * don't don't want to use this information when being
+	 * unloaded by kerneld even when the tape is full or when we
+	 * cannot allocate enough memory.
+	 */
+	if (pos->tape_pos > (volume->size-volume->blk_sz-ZFT_CMPR_OVERHEAD)) {
+		TRACE_EXIT -ENOSPC;
+	}    
+	if (zft_allocate_cmpr_mem(volume->blk_sz) < 0) {
+		/* should we unlock the module? But it shouldn't 
+		 * be locked anyway ...
+		 */
+		TRACE_EXIT -ENOMEM;
+	}
+	if (buf_pos_write == 0) { /* fill a new segment */
+		*write_cnt = buf_pos_write = start_new_cseg(&cseg,
+							    dst_buf,
+							    pos,
+							    volume->blk_sz,
+							    zftc_buf, 
+							    seg_sz,
+							    volume->qic113);
+		if (cseg.cmpr_sz == 0 && cseg.cmpr_pos != 0) {
+			req_len_left -= result = volume->blk_sz;
+			cseg.cmpr_pos  = 0;
+		} else {
+			result = 0;
+		}
+	} else {
+		*write_cnt = result = 0;
+	}
+	
+	len_left = seg_sz - buf_pos_write;
+	while ((req_len_left > 0) && (len_left > 18)) {
+		/* now we have some size left for a new compressed
+		 * block.  We know, that the compression buffer is
+		 * empty (else there wouldn't be any space left).  
+		 */
+		if (copy_from_user(zftc_scratch_buf, src_buf + result, 
+				   volume->blk_sz) != 0) {
+			TRACE_EXIT -EFAULT;
+		}
+		req_len_left -= volume->blk_sz;
+		cseg.cmpr_sz = zft_compress(zftc_scratch_buf, volume->blk_sz, 
+					    zftc_buf);
+		if (cseg.cmpr_sz < 0) {
+			cseg.uncmpr = 0x8000;
+			cseg.cmpr_sz = -cseg.cmpr_sz;
+		} else {
+			cseg.uncmpr = 0;
+		}
+		/* increment "result" iff we copied the entire
+		 * compressed block to the zft_deblock_buf 
+		 */
+		len_left -= sizeof(__u16);
+		if (len_left >= cseg.cmpr_sz) {
+			len_left -= cseg.count = cseg.cmpr_sz;
+			cseg.cmpr_pos = cseg.cmpr_sz = 0;
+			result += volume->blk_sz;
+		} else {
+			cseg.cmpr_sz       -= 
+				cseg.cmpr_pos =
+				cseg.count    = len_left;
+			len_left = 0;
+		}
+		PUT2(dst_buf, buf_pos_write, cseg.uncmpr | cseg.count);
+		buf_pos_write += sizeof(__u16);
+		memcpy(dst_buf + buf_pos_write, zftc_buf, cseg.count);
+		buf_pos_write += cseg.count;
+		*write_cnt    += cseg.count + sizeof(__u16);
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+	}
+	/* erase the remainder of the segment if less than 18 bytes
+	 * left (18 bytes is due to the QIC-80 standard) 
+	 */
+	if (len_left <= 18) {
+		memset(dst_buf + buf_pos_write, '\0', len_left);
+		(*write_cnt) += len_left;
+	}
+	TRACE(ft_t_data_flow, "returning %d", result);
+	TRACE_EXIT result;
+}   
+
+/* out:
+ *
+ * int *read_cnt: the number of bytes we removed from the zft_deblock_buf
+ *                (result)
+ * int *to_do   : the remaining size of the read-request.
+ *
+ * in:
+ *
+ * char *buff          : buff is the address of the upper part of the user
+ *                       buffer, that hasn't been filled with data yet.
+
+ * int buf_pos_read    : copy of from _ftape_read()
+ * int buf_len_read    : copy of buf_len_rd from _ftape_read()
+ * char *zft_deblock_buf: zft_deblock_buf
+ * unsigned short blk_sz: the block size valid for this volume, may differ
+ *                            from zft_blk_sz.
+ * int finish: if != 0 means that this is the last segment belonging
+ *  to this volume
+ * returns the amount of data actually copied to the user-buffer
+ *
+ * to_do MUST NOT SHRINK except to indicate an EOF. In this case *to_do has to
+ * be set to 0 
+ */
+static int zftc_read (int *read_cnt, 
+		      __u8  __user *dst_buf, const int to_do, 
+		      const __u8 *src_buf, const int seg_sz, 
+		      const zft_position *pos, const zft_volinfo *volume)
+{          
+	int uncompressed_sz;         
+	int result = 0;
+	int remaining = to_do;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE_CATCH(zft_allocate_cmpr_mem(volume->blk_sz),);
+	if (pos->seg_byte_pos == 0) {
+		/* new segment just read
+		 */
+		TRACE_CATCH(get_cseg(&cseg, src_buf, seg_sz, volume),
+			    *read_cnt = 0);
+		memcpy(zftc_buf + cseg.cmpr_pos, src_buf + sizeof(__u16), 
+		       cseg.count);
+		cseg.cmpr_pos += cseg.count;
+		*read_cnt      = cseg.offset;
+		DUMP_CMPR_INFO(ft_t_noise /* ft_t_any */, "", &cseg);
+	} else {
+		*read_cnt = 0;
+	}
+	/* loop and uncompress until user buffer full or
+	 * deblock-buffer empty 
+	 */
+	TRACE(ft_t_data_flow, "compressed_sz: %d, compos : %d, *read_cnt: %d",
+	      cseg.cmpr_sz, cseg.cmpr_pos, *read_cnt);
+	while ((cseg.spans == 0) && (remaining > 0)) {
+		if (cseg.cmpr_pos  != 0) { /* cmpr buf is not empty */
+			uncompressed_sz = 
+				zft_uncompress(zftc_buf,
+					       cseg.uncmpr == 0x8000 ?
+					       -cseg.cmpr_pos : cseg.cmpr_pos,
+					       zftc_scratch_buf,
+					       volume->blk_sz);
+			if (uncompressed_sz != volume->blk_sz) {
+				*read_cnt = 0;
+				TRACE_ABORT(-EIO, ft_t_warn,
+				      "Uncompressed blk (%d) != blk size (%d)",
+				      uncompressed_sz, volume->blk_sz);
+			}       
+			if (copy_to_user(dst_buf + result, 
+					 zftc_scratch_buf, 
+					 uncompressed_sz) != 0 ) {
+				TRACE_EXIT -EFAULT;
+			}
+			remaining      -= uncompressed_sz;
+			result     += uncompressed_sz;
+			cseg.cmpr_pos  = 0;
+		}                                              
+		if (remaining > 0) {
+			get_next_cluster(&cseg, src_buf, seg_sz, 
+					 volume->end_seg == pos->seg_pos);
+			if (cseg.count != 0) {
+				memcpy(zftc_buf, src_buf + cseg.offset,
+				       cseg.count);
+				cseg.cmpr_pos = cseg.count;
+				cseg.offset  += cseg.count;
+				*read_cnt += cseg.count + sizeof(__u16);
+			} else {
+				remaining = 0;
+			}
+		}
+		TRACE(ft_t_data_flow, "\n" 
+		      KERN_INFO "compressed_sz: %d\n"
+		      KERN_INFO "compos       : %d\n"
+		      KERN_INFO "*read_cnt    : %d",
+		      cseg.cmpr_sz, cseg.cmpr_pos, *read_cnt);
+	}
+	if (seg_sz - cseg.offset <= 18) {
+		*read_cnt += seg_sz - cseg.offset;
+		TRACE(ft_t_data_flow, "expanding read cnt to: %d", *read_cnt);
+	}
+	TRACE(ft_t_data_flow, "\n"
+	      KERN_INFO "segment size   : %d\n"
+	      KERN_INFO "read count     : %d\n"
+	      KERN_INFO "buf_pos_read   : %d\n"
+	      KERN_INFO "remaining      : %d",
+		seg_sz, *read_cnt, pos->seg_byte_pos, 
+		seg_sz - *read_cnt - pos->seg_byte_pos);
+	TRACE(ft_t_data_flow, "returning: %d", result);
+	TRACE_EXIT result;
+}                
+
+/* seeks to the new data-position. Reads sometimes a segment.
+ *  
+ * start_seg and end_seg give the boundaries of the current volume
+ * blk_sz is the blk_sz of the current volume as stored in the
+ * volume label
+ *
+ * We don't allow blocksizes less than 1024 bytes, therefore we don't need
+ * a 64 bit argument for new_block_pos.
+ */
+
+static int seek_in_segment(const unsigned int to_do, cmpr_info  *c_info,
+			   const char *src_buf, const int seg_sz, 
+			   const int seg_pos, const zft_volinfo *volume);
+static int slow_seek_forward_until_error(const unsigned int distance,
+					 cmpr_info *c_info, zft_position *pos, 
+					 const zft_volinfo *volume, __u8 *buf);
+static int search_valid_segment(unsigned int segment,
+				const unsigned int end_seg,
+				const unsigned int max_foffs,
+				zft_position *pos, cmpr_info *c_info,
+				const zft_volinfo *volume, __u8 *buf);
+static int slow_seek_forward(unsigned int dest, cmpr_info *c_info,
+			     zft_position *pos, const zft_volinfo *volume,
+			     __u8 *buf);
+static int compute_seg_pos(unsigned int dest, zft_position *pos,
+			   const zft_volinfo *volume);
+
+#define ZFT_SLOW_SEEK_THRESHOLD  10 /* segments */
+#define ZFT_FAST_SEEK_MAX_TRIALS 10 /* times */
+#define ZFT_FAST_SEEK_BACKUP     10 /* segments */
+
+static int zftc_seek(unsigned int new_block_pos,
+		     zft_position *pos, const zft_volinfo *volume, __u8 *buf)
+{
+	unsigned int dest;
+	int limit;
+	int distance;
+	int result = 0;
+	int seg_dist;
+	int new_seg;
+	int old_seg = 0;
+	int fast_seek_trials = 0;
+	TRACE_FUN(ft_t_flow);
+
+	if (new_block_pos == 0) {
+		pos->seg_pos      = volume->start_seg;
+		pos->seg_byte_pos = 0;
+		pos->volume_pos   = 0;
+		zftc_reset();
+		TRACE_EXIT 0;
+	}
+	dest = new_block_pos * (volume->blk_sz >> 10);
+	distance = dest - (pos->volume_pos >> 10);
+	while (distance != 0) {
+		seg_dist = compute_seg_pos(dest, pos, volume);
+		TRACE(ft_t_noise, "\n"
+		      KERN_INFO "seg_dist: %d\n"
+		      KERN_INFO "distance: %d\n"
+		      KERN_INFO "dest    : %d\n"
+		      KERN_INFO "vpos    : %d\n"
+		      KERN_INFO "seg_pos : %d\n"
+		      KERN_INFO "trials  : %d",
+		      seg_dist, distance, dest,
+		      (unsigned int)(pos->volume_pos>>10), pos->seg_pos,
+		      fast_seek_trials);
+		if (distance > 0) {
+			if (seg_dist < 0) {
+				TRACE(ft_t_bug, "BUG: distance %d > 0, "
+				      "segment difference %d < 0",
+				      distance, seg_dist);
+				result = -EIO;
+				break;
+			}
+			new_seg = pos->seg_pos + seg_dist;
+			if (new_seg > volume->end_seg) {
+				new_seg = volume->end_seg;
+			}
+			if (old_seg == new_seg || /* loop */
+			    seg_dist <= ZFT_SLOW_SEEK_THRESHOLD ||
+			    fast_seek_trials >= ZFT_FAST_SEEK_MAX_TRIALS) {
+				TRACE(ft_t_noise, "starting slow seek:\n"
+				   KERN_INFO "fast seek failed too often: %s\n"
+				   KERN_INFO "near target position      : %s\n"
+				   KERN_INFO "looping between two segs  : %s",
+				      (fast_seek_trials >= 
+				       ZFT_FAST_SEEK_MAX_TRIALS)
+				      ? "yes" : "no",
+				      (seg_dist <= ZFT_SLOW_SEEK_THRESHOLD) 
+				      ? "yes" : "no",
+				      (old_seg == new_seg)
+				      ? "yes" : "no");
+				result = slow_seek_forward(dest, &cseg, 
+							   pos, volume, buf);
+				break;
+			}
+			old_seg = new_seg;
+			limit = volume->end_seg;
+			fast_seek_trials ++;
+			for (;;) {
+				result = search_valid_segment(new_seg, limit,
+							      volume->size,
+							      pos, &cseg,
+							      volume, buf);
+				if (result == 0 || result == -EINTR) {
+					break;
+				}
+				if (new_seg == volume->start_seg) {
+					result = -EIO; /* set errror 
+							* condition
+							*/
+					break;
+				}
+				limit    = new_seg;
+				new_seg -= ZFT_FAST_SEEK_BACKUP;
+				if (new_seg < volume->start_seg) {
+					new_seg = volume->start_seg;
+				}
+			}
+			if (result < 0) {
+				TRACE(ft_t_warn,
+				      "Couldn't find a readable segment");
+				break;
+			}
+		} else /* if (distance < 0) */ {
+			if (seg_dist > 0) {
+				TRACE(ft_t_bug, "BUG: distance %d < 0, "
+				      "segment difference %d >0",
+				      distance, seg_dist);
+				result = -EIO;
+				break;
+			}
+			new_seg = pos->seg_pos + seg_dist;
+			if (fast_seek_trials > 0 && seg_dist == 0) {
+				/* this avoids sticking to the same
+				 * segment all the time. On the other hand:
+				 * if we got here for the first time, and the
+				 * deblock_buffer still contains a valid
+				 * segment, then there is no need to skip to 
+				 * the previous segment if the desired position
+				 * is inside this segment.
+				 */
+				new_seg --;
+			}
+			if (new_seg < volume->start_seg) {
+				new_seg = volume->start_seg;
+			}
+			limit   = pos->seg_pos;
+			fast_seek_trials ++;
+			for (;;) {
+				result = search_valid_segment(new_seg, limit,
+							      pos->volume_pos,
+							      pos, &cseg,
+							      volume, buf);
+				if (result == 0 || result == -EINTR) {
+					break;
+				}
+				if (new_seg == volume->start_seg) {
+					result = -EIO; /* set errror 
+							* condition
+							*/
+					break;
+				}
+				limit    = new_seg;
+				new_seg -= ZFT_FAST_SEEK_BACKUP;
+				if (new_seg < volume->start_seg) {
+					new_seg = volume->start_seg;
+				}
+			}
+			if (result < 0) {
+				TRACE(ft_t_warn,
+				      "Couldn't find a readable segment");
+				break;
+			}
+		}
+		distance = dest - (pos->volume_pos >> 10);
+	}
+	TRACE_EXIT result;
+}
+
+
+/*  advance inside the given segment at most to_do bytes.
+ *  of kilobytes moved
+ */
+
+static int seek_in_segment(const unsigned int to_do,
+			   cmpr_info  *c_info,
+			   const char *src_buf, 
+			   const int seg_sz, 
+			   const int seg_pos,
+			   const zft_volinfo *volume)
+{
+	int result = 0;
+	int blk_sz = volume->blk_sz >> 10;
+	int remaining = to_do;
+	TRACE_FUN(ft_t_flow);
+
+	if (c_info->offset == 0) {
+		/* new segment just read
+		 */
+		TRACE_CATCH(get_cseg(c_info, src_buf, seg_sz, volume),);
+		c_info->cmpr_pos += c_info->count;
+		DUMP_CMPR_INFO(ft_t_noise, "", c_info);
+	}
+	/* loop and uncompress until user buffer full or
+	 * deblock-buffer empty 
+	 */
+	TRACE(ft_t_noise, "compressed_sz: %d, compos : %d",
+	      c_info->cmpr_sz, c_info->cmpr_pos);
+	while (c_info->spans == 0 && remaining > 0) {
+		if (c_info->cmpr_pos  != 0) { /* cmpr buf is not empty */
+			result       += blk_sz;
+			remaining    -= blk_sz;
+			c_info->cmpr_pos = 0;
+		}
+		if (remaining > 0) {
+			get_next_cluster(c_info, src_buf, seg_sz, 
+					 volume->end_seg == seg_pos);
+			if (c_info->count != 0) {
+				c_info->cmpr_pos = c_info->count;
+				c_info->offset  += c_info->count;
+			} else {
+				break;
+			}
+		}
+		/*  Allow escape from this loop on signal!
+		 */
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		DUMP_CMPR_INFO(ft_t_noise, "", c_info);
+		TRACE(ft_t_noise, "to_do: %d", remaining);
+	}
+	if (seg_sz - c_info->offset <= 18) {
+		c_info->offset = seg_sz;
+	}
+	TRACE(ft_t_noise, "\n"
+	      KERN_INFO "segment size   : %d\n"
+	      KERN_INFO "buf_pos_read   : %d\n"
+	      KERN_INFO "remaining      : %d",
+	      seg_sz, c_info->offset,
+	      seg_sz - c_info->offset);
+	TRACE_EXIT result;
+}                
+
+static int slow_seek_forward_until_error(const unsigned int distance,
+					 cmpr_info *c_info,
+					 zft_position *pos, 
+					 const zft_volinfo *volume,
+					 __u8 *buf)
+{
+	unsigned int remaining = distance;
+	int seg_sz;
+	int seg_pos;
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	seg_pos = pos->seg_pos;
+	do {
+		TRACE_CATCH(seg_sz = zft_fetch_segment(seg_pos, buf, 
+						       FT_RD_AHEAD),);
+		/* now we have the contents of the actual segment in
+		 * the deblock buffer
+		 */
+		TRACE_CATCH(result = seek_in_segment(remaining, c_info, buf,
+						     seg_sz, seg_pos,volume),);
+		remaining        -= result;
+		pos->volume_pos  += result<<10;
+		pos->seg_pos      = seg_pos;
+		pos->seg_byte_pos = c_info->offset;
+		seg_pos ++;
+		if (seg_pos <= volume->end_seg && c_info->offset == seg_sz) {
+			pos->seg_pos ++;
+			pos->seg_byte_pos = 0;
+			c_info->offset = 0;
+		}
+		/*  Allow escape from this loop on signal!
+		 */
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		TRACE(ft_t_noise, "\n"
+		      KERN_INFO "remaining:  %d\n"
+		      KERN_INFO "seg_pos:    %d\n"
+		      KERN_INFO "end_seg:    %d\n"
+		      KERN_INFO "result:     %d",
+		      remaining, seg_pos, volume->end_seg, result);  
+	} while (remaining > 0 && seg_pos <= volume->end_seg);
+	TRACE_EXIT 0;
+}
+
+/* return segment id of next segment containing valid data, -EIO otherwise
+ */
+static int search_valid_segment(unsigned int segment,
+				const unsigned int end_seg,
+				const unsigned int max_foffs,
+				zft_position *pos,
+				cmpr_info *c_info,
+				const zft_volinfo *volume,
+				__u8 *buf)
+{
+	cmpr_info tmp_info;
+	int seg_sz;
+	TRACE_FUN(ft_t_flow);
+	
+	memset(&tmp_info, 0, sizeof(cmpr_info));
+	while (segment <= end_seg) {
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		TRACE(ft_t_noise,
+		      "Searching readable segment between %d and %d",
+		      segment, end_seg);
+		seg_sz = zft_fetch_segment(segment, buf, FT_RD_AHEAD);
+		if ((seg_sz > 0) &&
+		    (get_cseg (&tmp_info, buf, seg_sz, volume) >= 0) &&
+		    (tmp_info.foffs != 0 || segment == volume->start_seg)) {
+			if ((tmp_info.foffs>>10) > max_foffs) {
+				TRACE_ABORT(-EIO, ft_t_noise, "\n"
+					    KERN_INFO "cseg.foff: %d\n"
+					    KERN_INFO "dest     : %d",
+					    (int)(tmp_info.foffs >> 10),
+					    max_foffs);
+			}
+			DUMP_CMPR_INFO(ft_t_noise, "", &tmp_info);
+			*c_info           = tmp_info;
+			pos->seg_pos      = segment;
+			pos->volume_pos   = c_info->foffs;
+			pos->seg_byte_pos = c_info->offset;
+			TRACE(ft_t_noise, "found segment at %d", segment);
+			TRACE_EXIT 0;
+		}
+		segment++;
+	}
+	TRACE_EXIT -EIO;
+}
+
+static int slow_seek_forward(unsigned int dest,
+			     cmpr_info *c_info,
+			     zft_position *pos,
+			     const zft_volinfo *volume,
+			     __u8 *buf)
+{
+	unsigned int distance;
+	int result = 0;
+	TRACE_FUN(ft_t_flow);
+		
+	distance = dest - (pos->volume_pos >> 10);
+	while ((distance > 0) &&
+	       (result = slow_seek_forward_until_error(distance,
+						       c_info,
+						       pos,
+						       volume,
+						       buf)) < 0) {
+		if (result == -EINTR) {
+			break;
+		}
+		TRACE(ft_t_noise, "seg_pos: %d", pos->seg_pos);
+		/* the failing segment is either pos->seg_pos or
+		 * pos->seg_pos + 1. There is no need to further try
+		 * that segment, because ftape_read_segment() already
+		 * has tried very much to read it. So we start with
+		 * following segment, which is pos->seg_pos + 1
+		 */
+		if(search_valid_segment(pos->seg_pos+1, volume->end_seg, dest,
+					pos, c_info,
+					volume, buf) < 0) {
+			TRACE(ft_t_noise, "search_valid_segment() failed");
+			result = -EIO;
+			break;
+		}
+		distance = dest - (pos->volume_pos >> 10);
+		result = 0;
+		TRACE(ft_t_noise, "segment: %d", pos->seg_pos);
+		/* found valid segment, retry the seek */
+	}
+	TRACE_EXIT result;
+}
+
+static int compute_seg_pos(const unsigned int dest,
+			   zft_position *pos,
+			   const zft_volinfo *volume)
+{
+	int segment;
+	int distance = dest - (pos->volume_pos >> 10);
+	unsigned int raw_size;
+	unsigned int virt_size;
+	unsigned int factor;
+	TRACE_FUN(ft_t_flow);
+
+	if (distance >= 0) {
+		raw_size  = volume->end_seg - pos->seg_pos + 1;
+		virt_size = ((unsigned int)(volume->size>>10) 
+			     - (unsigned int)(pos->volume_pos>>10)
+			     + FT_SECTORS_PER_SEGMENT - FT_ECC_SECTORS - 1);
+		virt_size /= FT_SECTORS_PER_SEGMENT - FT_ECC_SECTORS;
+		if (virt_size == 0 || raw_size == 0) {
+			TRACE_EXIT 0;
+		}
+		if (raw_size >= (1<<25)) {
+			factor = raw_size/(virt_size>>7);
+		} else {
+			factor = (raw_size<<7)/virt_size;
+		}
+		segment = distance/(FT_SECTORS_PER_SEGMENT-FT_ECC_SECTORS);
+		segment = (segment * factor)>>7;
+	} else {
+		raw_size  = pos->seg_pos - volume->start_seg + 1;
+		virt_size = ((unsigned int)(pos->volume_pos>>10)
+			     + FT_SECTORS_PER_SEGMENT - FT_ECC_SECTORS - 1);
+		virt_size /= FT_SECTORS_PER_SEGMENT - FT_ECC_SECTORS;
+		if (virt_size == 0 || raw_size == 0) {
+			TRACE_EXIT 0;
+		}
+		if (raw_size >= (1<<25)) {
+			factor = raw_size/(virt_size>>7);
+		} else {
+			factor = (raw_size<<7)/virt_size;
+		}
+		segment = distance/(FT_SECTORS_PER_SEGMENT-FT_ECC_SECTORS);
+	}
+	TRACE(ft_t_noise, "factor: %d/%d", factor, 1<<7);
+	TRACE_EXIT segment;
+}
+
+static struct zft_cmpr_ops cmpr_ops = {
+	zftc_write,
+	zftc_read,
+	zftc_seek,
+	zftc_lock,
+	zftc_reset,
+	zftc_cleanup
+};
+
+int zft_compressor_init(void)
+{
+	TRACE_FUN(ft_t_flow);
+	
+#ifdef MODULE
+	printk(KERN_INFO "zftape compressor v1.00a 970514 for " FTAPE_VERSION "\n");
+        if (TRACE_LEVEL >= ft_t_info) {
+		printk(
+KERN_INFO "(c) 1997 Claus-Justus Heine (claus@momo.math.rwth-aachen.de)\n"
+KERN_INFO "Compressor for zftape (lzrw3 algorithm)\n");
+        }
+#else /* !MODULE */
+	/* print a short no-nonsense boot message */
+	printk("zftape compressor v1.00a 970514\n");
+	printk("For use with " FTAPE_VERSION "\n");
+#endif /* MODULE */
+	TRACE(ft_t_info, "zft_compressor_init @ 0x%p", zft_compressor_init);
+	TRACE(ft_t_info, "installing compressor for zftape ...");
+	TRACE_CATCH(zft_cmpr_register(&cmpr_ops),);
+	TRACE_EXIT 0;
+}
+
+#ifdef MODULE
+
+MODULE_AUTHOR(
+	"(c) 1996, 1997 Claus-Justus Heine (claus@momo.math.rwth-aachen.de");
+MODULE_DESCRIPTION(
+"Compression routines for zftape. Uses the lzrw3 algorithm by Ross Williams");
+MODULE_LICENSE("GPL");
+
+/* Called by modules package when installing the driver
+ */
+int init_module(void)
+{
+	return zft_compressor_init();
+}
+
+#endif /* MODULE */
diff --git a/drivers/char/ftape/compressor/zftape-compress.h b/drivers/char/ftape/compressor/zftape-compress.h
new file mode 100644
index 0000000..f200741
--- /dev/null
+++ b/drivers/char/ftape/compressor/zftape-compress.h
@@ -0,0 +1,83 @@
+#ifndef _ZFTAPE_COMPRESS_H
+#define _ZFTAPE_COMPRESS_H
+/*
+ *      Copyright (c) 1994-1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2, or (at
+ your option) any later version.
+ 
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+ 
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/compressor/zftape-compress.h,v $
+ * $Revision: 1.1 $
+ * $Date: 1997/10/05 19:12:32 $
+ *
+ * This file contains macros and definitions for zftape's
+ * builtin compression code.
+ *
+ */
+
+#include "../zftape/zftape-buffers.h"
+#include "../zftape/zftape-vtbl.h"
+#include "../compressor/lzrw3.h"
+
+/* CMPR_WRK_MEM_SIZE gives the size of the compression wrk_mem */
+/* I got these out of lzrw3.c */
+#define U(X)            ((__u32) X)
+#define SIZE_P_BYTE     (U(sizeof(__u8 *)))
+#define ALIGNMENT_FUDGE (U(16))
+
+#define CMPR_WRK_MEM_SIZE (U(4096)*(SIZE_P_BYTE) + ALIGNMENT_FUDGE)
+
+/* the maximum number of bytes the size of the "compressed" data can
+ * exceed the uncompressed data. As it is quite useless to compress
+ * data twice it is sometimes the case that it is more efficient to
+ * copy a block of data but to feed it to the "compression"
+ * algorithm. In this case there are some flag bytes or the like
+ * proceding the "compressed" data.  THAT MUST NOT BE THE CASE for the
+ * algorithm we use for this driver. Instead, the high bit 15 of
+ * compressed_size:
+ *
+ * compressed_size = ftape_compress()
+ *
+ * must be set in such a case.
+ *
+ * Nevertheless, it might also be as for lzrw3 that there is an
+ * "intermediate" overrun that exceeds the amount of the compressed
+ * data that is actually produced. During the algorithm we need in the
+ * worst case MAX_CMP_GROUP bytes more than the input-size.
+ */
+#define MAX_CMP_GROUP (2+16*2) /* from lzrw3.c */
+
+#define CMPR_OVERRUN      MAX_CMP_GROUP /* during compression */
+
+/****************************************************/
+
+#define     CMPR_BUFFER_SIZE (MAX_BLOCK_SIZE + CMPR_OVERRUN)
+
+/* the compression map stores the byte offset compressed blocks within
+ * the current volume for catridges with format code 2,3 and 5
+ * (and old versions of zftape) and the offset measured in kilobytes for
+ * format code 4 and 6. This gives us a possible max. size of a 
+ * compressed volume of 1024*4GIG which should be enough.
+ */
+typedef __u32 CmprMap;
+
+/* globals 
+ */
+
+/* exported functions
+ */
+
+#endif /* _ZFTAPE_COMPRESS_H */
diff --git a/drivers/char/ftape/lowlevel/Makefile b/drivers/char/ftape/lowlevel/Makefile
new file mode 100644
index 0000000..febab07
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/Makefile
@@ -0,0 +1,43 @@
+#
+#       Copyright (C) 1996, 1997 Clau-Justus Heine.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; see the file COPYING.  If not, write to
+# the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+#
+# $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/Makefile,v $
+# $Revision: 1.4 $
+# $Date: 1997/10/07 09:26:02 $
+#
+#      Makefile for the lowlevel part QIC-40/80/3010/3020 floppy-tape
+#      driver for Linux.
+#
+
+obj-$(CONFIG_FTAPE) += ftape.o
+
+ftape-objs := ftape-init.o fdc-io.o fdc-isr.o \
+	      ftape-bsm.o ftape-ctl.o ftape-read.o ftape-rw.o \
+	      ftape-write.o ftape-io.o ftape-calibr.o ftape-ecc.o fc-10.o \
+	      ftape-buffer.o ftape-format.o ftape_syms.o
+
+ifeq ($(CONFIG_FTAPE),y)
+ftape-objs += ftape-setup.o
+endif
+
+ifndef CONFIG_FT_NO_TRACE_AT_ALL
+ftape-objs += ftape-tracing.o
+endif
+
+ifeq ($(CONFIG_FT_PROC_FS),y)
+ftape-objs += ftape-proc.o
+endif
diff --git a/drivers/char/ftape/lowlevel/fc-10.c b/drivers/char/ftape/lowlevel/fc-10.c
new file mode 100644
index 0000000..9bc1cdd
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/fc-10.c
@@ -0,0 +1,175 @@
+/*
+ *
+
+   Copyright (C) 1993,1994 Jon Tombs.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   The entire guts of this program was written by dosemu, modified to
+   record reads and writes to the ports in the 0x180-0x188 address space,
+   while running the CMS program TAPE.EXE V2.0.5 supplied with the drive.
+
+   Modified to use an array of addresses and generally cleaned up (made
+   much shorter) 4 June 94, dosemu isn't that good at writing short code it
+   would seem :-). Made independent of 0x180, but I doubt it will work
+   at any other address.
+
+   Modified for distribution with ftape source. 21 June 94, SJL.
+
+   Modifications on 20 October 95, by Daniel Cohen (catman@wpi.edu):
+   Modified to support different DMA, IRQ, and IO Ports.  Borland's
+   Turbo Debugger in virtual 8086 mode (TD386.EXE with hardware breakpoints
+   provided by the TDH386.SYS Device Driver) was used on the CMS program
+   TAPE V4.0.5.  I set breakpoints on I/O to ports 0x180-0x187.  Note that
+   CMS's program will not successfully configure the tape drive if you set
+   breakpoints on IO Reads, but you can set them on IO Writes without problems.
+   Known problems:
+   - You can not use DMA Channels 5 or 7.
+
+   Modification on 29 January 96, by Daniel Cohen (catman@wpi.edu):
+   Modified to only accept IRQs 3 - 7, or 9.  Since we can only send a 3 bit
+   number representing the IRQ to the card, special handling is required when
+   IRQ 9 is selected.  IRQ 2 and 9 are the same, and we should request IRQ 9
+   from the kernel while telling the card to use IRQ 2.  Thanks to Greg
+   Crider (gcrider@iclnet.org) for finding and locating this bug, as well as
+   testing the patch.
+
+   Modification on 11 December 96, by Claus Heine (claus@momo.math.rwth-aachen.de):
+   Modified a little to use variahle ft_fdc_base, ft_fdc_irq, ft_fdc_dma 
+   instead of preprocessor symbols. Thus we can compile this into the module
+   or kernel and let the user specify the options as command line arguments.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/fc-10.c,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:04 $
+ *
+ *      This file contains code for the CMS FC-10/FC-20 card.
+ */
+
+#include <asm/io.h>
+#include <linux/ftape.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/fdc-io.h"
+#include "../lowlevel/fc-10.h"
+
+static __u16 inbs_magic[] = {
+	0x3, 0x3, 0x0, 0x4, 0x7, 0x2, 0x5, 0x3, 0x1, 0x4,
+	0x3, 0x5, 0x2, 0x0, 0x3, 0x7, 0x4, 0x2,
+	0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7
+};
+
+static __u16 fc10_ports[] = {
+	0x180, 0x210, 0x2A0, 0x300, 0x330, 0x340, 0x370
+};
+
+int fc10_enable(void)
+{
+	int i;
+	__u8 cardConfig = 0x00;
+	__u8 x;
+	TRACE_FUN(ft_t_flow);
+
+/*  This code will only work if the FC-10 (or FC-20) is set to
+ *  use DMA channels 1, 2, or 3.  DMA channels 5 and 7 seem to be 
+ *  initialized by the same command as channels 1 and 3, respectively.
+ */
+	if (ft_fdc_dma > 3) {
+		TRACE_ABORT(0, ft_t_err,
+"Error: The FC-10/20 must be set to use DMA channels 1, 2, or 3!");
+	}
+/*  Only allow the FC-10/20 to use IRQ 3-7, or 9.  Note that CMS's program
+ *  only accepts IRQ's 2-7, but in linux, IRQ 2 is the same as IRQ 9.
+ */
+	if (ft_fdc_irq < 3 || ft_fdc_irq == 8 || ft_fdc_irq > 9) {
+		TRACE_ABORT(0, ft_t_err, 
+"Error: The FC-10/20 must be set to use IRQ levels 3 - 7, or 9!\n"
+KERN_INFO "Note: IRQ 9 is the same as IRQ 2");
+	}
+	/*  Clear state machine ???
+	 */
+	for (i = 0; i < NR_ITEMS(inbs_magic); i++) {
+		inb(ft_fdc_base + inbs_magic[i]);
+	}
+	outb(0x0, ft_fdc_base);
+
+	x = inb(ft_fdc_base);
+	if (x == 0x13 || x == 0x93) {
+		for (i = 1; i < 8; i++) {
+			if (inb(ft_fdc_base + i) != x) {
+				TRACE_EXIT 0;
+			}
+		}
+	} else {
+		TRACE_EXIT 0;
+	}
+
+	outb(0x8, ft_fdc_base);
+
+	for (i = 0; i < 8; i++) {
+		if (inb(ft_fdc_base + i) != 0x0) {
+			TRACE_EXIT 0;
+		}
+	}
+	outb(0x10, ft_fdc_base);
+
+	for (i = 0; i < 8; i++) {
+		if (inb(ft_fdc_base + i) != 0xff) {
+			TRACE_EXIT 0;
+		}
+	}
+
+	/*  Okay, we found a FC-10 card ! ???
+	 */
+	outb(0x0, fdc.ccr);
+
+	/*  Clear state machine again ???
+	 */
+	for (i = 0; i < NR_ITEMS(inbs_magic); i++) {
+		inb(ft_fdc_base + inbs_magic[i]);
+	}
+	/* Send io port */
+	for (i = 0; i < NR_ITEMS(fc10_ports); i++)
+		if (ft_fdc_base == fc10_ports[i])
+			cardConfig = i + 1;
+	if (cardConfig == 0) {
+		TRACE_EXIT 0;	/* Invalid I/O Port */
+	}
+	/* and IRQ - If using IRQ 9, tell the FC card it is actually IRQ 2 */
+	if (ft_fdc_irq != 9)
+		cardConfig |= ft_fdc_irq << 3;
+	else
+		cardConfig |= 2 << 3;
+
+	/* and finally DMA Channel */
+	cardConfig |= ft_fdc_dma << 6;
+	outb(cardConfig, ft_fdc_base);	/* DMA [2 bits]/IRQ [3 bits]/BASE [3 bits] */
+
+	/*  Enable FC-10 ???
+	 */
+	outb(0, fdc.ccr);
+	outb(0, fdc.dor2);
+	outb(FDC_DMA_MODE /* 8 */, fdc.dor);
+	outb(FDC_DMA_MODE /* 8 */, fdc.dor);
+	outb(1, fdc.dor2);
+
+	/*************************************
+	 *
+	 * cH: why the hell should this be necessary? This is done 
+	 *     by fdc_reset()!!!
+	 *
+	 *************************************/
+	/*  Initialize fdc, select drive B:
+	 */
+	outb(FDC_DMA_MODE, fdc.dor);	/* assert reset, dma & irq enabled */
+	/*       0x08    */
+	outb(FDC_DMA_MODE|FDC_RESET_NOT, fdc.dor);	/* release reset */
+	/*       0x08    |   0x04   = 0x0c */
+	outb(FDC_DMA_MODE|FDC_RESET_NOT|FDC_MOTOR_1|FTAPE_SEL_B, fdc.dor);
+	/*       0x08    |   0x04      |  0x20     |  0x01  = 0x2d */    
+	/* select drive 1 */ /* why not drive 0 ???? */
+	TRACE_EXIT (x == 0x93) ? 2 : 1;
+}
diff --git a/drivers/char/ftape/lowlevel/fc-10.h b/drivers/char/ftape/lowlevel/fc-10.h
new file mode 100644
index 0000000..da7b88b
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/fc-10.h
@@ -0,0 +1,39 @@
+#ifndef _FC_10_H
+#define _FC_10_H
+
+/*
+ * Copyright (C) 1994-1996 Bas Laarhoven.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/fc-10.h,v $
+ * $Revision: 1.1 $
+ * $Date: 1997/09/19 09:05:22 $
+ *
+ *      This file contains definitions for the FC-10 code
+ *      of the QIC-40/80 floppy-tape driver for Linux.
+ */
+
+/*
+ *      fc-10.c defined global vars.
+ */
+
+/*
+ *      fc-10.c defined global functions.
+ */
+extern int fc10_enable(void);
+
+#endif
diff --git a/drivers/char/ftape/lowlevel/fdc-io.c b/drivers/char/ftape/lowlevel/fdc-io.c
new file mode 100644
index 0000000..1704a2a
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/fdc-io.c
@@ -0,0 +1,1352 @@
+/*
+ * Copyright (C) 1993-1996 Bas Laarhoven,
+ *           (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/fdc-io.c,v $
+ * $Revision: 1.7.4.2 $
+ * $Date: 1997/11/16 14:48:17 $
+ *
+ *      This file contains the low-level floppy disk interface code
+ *      for the QIC-40/80/3010/3020 floppy-tape driver "ftape" for
+ *      Linux.
+ */
+
+#include <linux/config.h> /* for CONFIG_FT_* */
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/ioport.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#include <asm/dma.h>
+#include <asm/irq.h>
+
+#include <linux/ftape.h>
+#include <linux/qic117.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/fdc-io.h"
+#include "../lowlevel/fdc-isr.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-calibr.h"
+#include "../lowlevel/fc-10.h"
+
+/*      Global vars.
+ */
+static int ftape_motor;
+volatile int ftape_current_cylinder = -1;
+volatile fdc_mode_enum fdc_mode = fdc_idle;
+fdc_config_info fdc;
+DECLARE_WAIT_QUEUE_HEAD(ftape_wait_intr);
+
+unsigned int ft_fdc_base       = CONFIG_FT_FDC_BASE;
+unsigned int ft_fdc_irq        = CONFIG_FT_FDC_IRQ;
+unsigned int ft_fdc_dma        = CONFIG_FT_FDC_DMA;
+unsigned int ft_fdc_threshold  = CONFIG_FT_FDC_THR;  /* bytes */
+unsigned int ft_fdc_rate_limit = CONFIG_FT_FDC_MAX_RATE; /* bits/sec */
+int ft_probe_fc10        = CONFIG_FT_PROBE_FC10;
+int ft_mach2             = CONFIG_FT_MACH2;
+
+/*      Local vars.
+ */
+static spinlock_t fdc_io_lock; 
+static unsigned int fdc_calibr_count;
+static unsigned int fdc_calibr_time;
+static int fdc_status;
+volatile __u8 fdc_head;		/* FDC head from sector id */
+volatile __u8 fdc_cyl;		/* FDC track from sector id */
+volatile __u8 fdc_sect;		/* FDC sector from sector id */
+static int fdc_data_rate = 500;	/* data rate (Kbps) */
+static int fdc_rate_code;	/* data rate code (0 == 500 Kbps) */
+static int fdc_seek_rate = 2;	/* step rate (msec) */
+static void (*do_ftape) (void);
+static int fdc_fifo_state;	/* original fifo setting - fifo enabled */
+static int fdc_fifo_thr;	/* original fifo setting - threshold */
+static int fdc_lock_state;	/* original lock setting - locked */
+static int fdc_fifo_locked;	/* has fifo && lock set ? */
+static __u8 fdc_precomp;	/* default precomp. value (nsec) */
+static __u8 fdc_prec_code;	/* fdc precomp. select code */
+
+static char ftape_id[] = "ftape";  /* used by request irq and free irq */
+
+static int fdc_set_seek_rate(int seek_rate);
+
+void fdc_catch_stray_interrupts(int count)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&fdc_io_lock, flags);
+	if (count == 0) {
+		ft_expected_stray_interrupts = 0;
+	} else {
+		ft_expected_stray_interrupts += count;
+	}
+	spin_unlock_irqrestore(&fdc_io_lock, flags);
+}
+
+/*  Wait during a timeout period for a given FDC status.
+ *  If usecs == 0 then just test status, else wait at least for usecs.
+ *  Returns -ETIME on timeout. Function must be calibrated first !
+ */
+static int fdc_wait(unsigned int usecs, __u8 mask, __u8 state)
+{
+	int count_1 = (fdc_calibr_count * usecs +
+                       fdc_calibr_count - 1) / fdc_calibr_time;
+
+	do {
+		fdc_status = inb_p(fdc.msr);
+		if ((fdc_status & mask) == state) {
+			return 0;
+		}
+	} while (count_1-- >= 0);
+	return -ETIME;
+}
+
+int fdc_ready_wait(unsigned int usecs)
+{
+	return fdc_wait(usecs, FDC_DATA_READY | FDC_BUSY, FDC_DATA_READY);
+}
+
+/* Why can't we just use udelay()?
+ */
+static void fdc_usec_wait(unsigned int usecs)
+{
+	fdc_wait(usecs, 0, 1);	/* will always timeout ! */
+}
+
+static int fdc_ready_out_wait(unsigned int usecs)
+{
+	fdc_usec_wait(FT_RQM_DELAY);	/* wait for valid RQM status */
+	return fdc_wait(usecs, FDC_DATA_OUT_READY, FDC_DATA_OUT_READY);
+}
+
+void fdc_wait_calibrate(void)
+{
+	ftape_calibrate("fdc_wait",
+			fdc_usec_wait, &fdc_calibr_count, &fdc_calibr_time); 
+}
+
+/*  Wait for a (short) while for the FDC to become ready
+ *  and transfer the next command byte.
+ *  Return -ETIME on timeout on getting ready (depends on hardware!).
+ */
+static int fdc_write(const __u8 data)
+{
+	fdc_usec_wait(FT_RQM_DELAY);	/* wait for valid RQM status */
+	if (fdc_wait(150, FDC_DATA_READY_MASK, FDC_DATA_IN_READY) < 0) {
+		return -ETIME;
+	} else {
+		outb(data, fdc.fifo);
+		return 0;
+	}
+}
+
+/*  Wait for a (short) while for the FDC to become ready
+ *  and transfer the next result byte.
+ *  Return -ETIME if timeout on getting ready (depends on hardware!).
+ */
+static int fdc_read(__u8 * data)
+{
+	fdc_usec_wait(FT_RQM_DELAY);	/* wait for valid RQM status */
+	if (fdc_wait(150, FDC_DATA_READY_MASK, FDC_DATA_OUT_READY) < 0) {
+		return -ETIME;
+	} else {
+		*data = inb(fdc.fifo);
+		return 0;
+	}
+}
+
+/*  Output a cmd_len long command string to the FDC.
+ *  The FDC should be ready to receive a new command or
+ *  an error (EBUSY or ETIME) will occur.
+ */
+int fdc_command(const __u8 * cmd_data, int cmd_len)
+{
+	int result = 0;
+	unsigned long flags;
+	int count = cmd_len;
+	int retry = 0;
+#ifdef TESTING
+	static unsigned int last_time;
+	unsigned int time;
+#endif
+	TRACE_FUN(ft_t_any);
+
+	fdc_usec_wait(FT_RQM_DELAY);	/* wait for valid RQM status */
+	spin_lock_irqsave(&fdc_io_lock, flags);
+	if (!in_interrupt())
+		/* Yes, I know, too much comments inside this function
+		 * ...
+		 * 
+		 * Yet another bug in the original driver. All that
+		 * havoc is caused by the fact that the isr() sends
+		 * itself a command to the floppy tape driver (pause,
+		 * micro step pause).  Now, the problem is that
+		 * commands are transmitted via the fdc_seek
+		 * command. But: the fdc performs seeks in the
+		 * background i.e. it doesn't signal busy while
+		 * sending the step pulses to the drive. Therefore the
+		 * non-interrupt level driver has no chance to tell
+		 * whether the isr() just has issued a seek. Therefore
+		 * we HAVE TO have a look at the ft_hide_interrupt
+		 * flag: it signals the non-interrupt level part of
+		 * the driver that it has to wait for the fdc until it
+		 * has completet seeking.
+		 *
+		 * THIS WAS PRESUMABLY THE REASON FOR ALL THAT
+		 * "fdc_read timeout" errors, I HOPE :-)
+		 */
+		if (ft_hide_interrupt) {
+			restore_flags(flags);
+			TRACE(ft_t_info,
+			      "Waiting for the isr() completing fdc_seek()");
+			if (fdc_interrupt_wait(2 * FT_SECOND) < 0) {
+				TRACE(ft_t_warn,
+		      "Warning: timeout waiting for isr() seek to complete");
+			}
+			if (ft_hide_interrupt || !ft_seek_completed) {
+				/* There cannot be another
+				 * interrupt. The isr() only stops
+				 * the tape and the next interrupt
+				 * won't come until we have send our
+				 * command to the drive.
+				 */
+				TRACE_ABORT(-EIO, ft_t_bug,
+					    "BUG? isr() is still seeking?\n"
+					    KERN_INFO "hide: %d\n"
+					    KERN_INFO "seek: %d",
+					    ft_hide_interrupt,
+					    ft_seek_completed);
+
+			}
+			fdc_usec_wait(FT_RQM_DELAY);	/* wait for valid RQM status */
+			spin_lock_irqsave(&fdc_io_lock, flags);
+		}
+	fdc_status = inb(fdc.msr);
+	if ((fdc_status & FDC_DATA_READY_MASK) != FDC_DATA_IN_READY) {
+		spin_unlock_irqrestore(&fdc_io_lock, flags);
+		TRACE_ABORT(-EBUSY, ft_t_err, "fdc not ready");
+	} 
+	fdc_mode = *cmd_data;	/* used by isr */
+#ifdef TESTING
+	if (fdc_mode == FDC_SEEK) {
+		time = ftape_timediff(last_time, ftape_timestamp());
+		if (time < 6000) {
+	TRACE(ft_t_bug,"Warning: short timeout between seek commands: %d",
+	      time);
+		}
+	}
+#endif
+	if (!in_interrupt()) {
+		/* shouldn't be cleared if called from isr
+		 */
+		ft_interrupt_seen = 0;
+	}
+	while (count) {
+		result = fdc_write(*cmd_data);
+		if (result < 0) {
+			TRACE(ft_t_fdc_dma,
+			      "fdc_mode = %02x, status = %02x at index %d",
+			      (int) fdc_mode, (int) fdc_status,
+			      cmd_len - count);
+			if (++retry <= 3) {
+				TRACE(ft_t_warn, "fdc_write timeout, retry");
+			} else {
+				TRACE(ft_t_err, "fdc_write timeout, fatal");
+				/* recover ??? */
+				break;
+			}
+		} else {
+			--count;
+			++cmd_data;
+		}
+        }
+#ifdef TESTING
+	if (fdc_mode == FDC_SEEK) {
+		last_time = ftape_timestamp();
+	}
+#endif
+	spin_unlock_irqrestore(&fdc_io_lock, flags);
+	TRACE_EXIT result;
+}
+
+/*  Input a res_len long result string from the FDC.
+ *  The FDC should be ready to send the result or an error
+ *  (EBUSY or ETIME) will occur.
+ */
+int fdc_result(__u8 * res_data, int res_len)
+{
+	int result = 0;
+	unsigned long flags;
+	int count = res_len;
+	int retry = 0;
+	TRACE_FUN(ft_t_any);
+
+	spin_lock_irqsave(&fdc_io_lock, flags);
+	fdc_status = inb(fdc.msr);
+	if ((fdc_status & FDC_DATA_READY_MASK) != FDC_DATA_OUT_READY) {
+		TRACE(ft_t_err, "fdc not ready");
+		result = -EBUSY;
+	} else while (count) {
+		if (!(fdc_status & FDC_BUSY)) {
+			spin_unlock_irqrestore(&fdc_io_lock, flags);
+			TRACE_ABORT(-EIO, ft_t_err, "premature end of result phase");
+		}
+		result = fdc_read(res_data);
+		if (result < 0) {
+			TRACE(ft_t_fdc_dma,
+			      "fdc_mode = %02x, status = %02x at index %d",
+			      (int) fdc_mode,
+			      (int) fdc_status,
+			      res_len - count);
+			if (++retry <= 3) {
+				TRACE(ft_t_warn, "fdc_read timeout, retry");
+			} else {
+				TRACE(ft_t_err, "fdc_read timeout, fatal");
+				/* recover ??? */
+				break;
+				++retry;
+			}
+		} else {
+			--count;
+			++res_data;
+		}
+	}
+	spin_unlock_irqrestore(&fdc_io_lock, flags);
+	fdc_usec_wait(FT_RQM_DELAY);	/* allow FDC to negate BSY */
+	TRACE_EXIT result;
+}
+
+/*      Handle command and result phases for
+ *      commands without data phase.
+ */
+static int fdc_issue_command(const __u8 * out_data, int out_count,
+		      __u8 * in_data, int in_count)
+{
+	TRACE_FUN(ft_t_any);
+
+	if (out_count > 0) {
+		TRACE_CATCH(fdc_command(out_data, out_count),);
+	}
+	/* will take 24 - 30 usec for fdc_sense_drive_status and
+	 * fdc_sense_interrupt_status commands.
+	 *    35 fails sometimes (5/9/93 SJL)
+	 * On a loaded system it incidentally takes longer than
+	 * this for the fdc to get ready ! ?????? WHY ??????
+	 * So until we know what's going on use a very long timeout.
+	 */
+	TRACE_CATCH(fdc_ready_out_wait(500 /* usec */),);
+	if (in_count > 0) {
+		TRACE_CATCH(fdc_result(in_data, in_count),
+			    TRACE(ft_t_err, "result phase aborted"));
+	}
+	TRACE_EXIT 0;
+}
+
+/*      Wait for FDC interrupt with timeout (in milliseconds).
+ *      Signals are blocked so the wait will not be aborted.
+ *      Note: interrupts must be enabled ! (23/05/93 SJL)
+ */
+int fdc_interrupt_wait(unsigned int time)
+{
+	DECLARE_WAITQUEUE(wait,current);
+	sigset_t old_sigmask;	
+	static int resetting;
+	long timeout;
+
+	TRACE_FUN(ft_t_fdc_dma);
+
+ 	if (waitqueue_active(&ftape_wait_intr)) {
+		TRACE_ABORT(-EIO, ft_t_err, "error: nested call");
+	}
+	/* timeout time will be up to USPT microseconds too long ! */
+	timeout = (1000 * time + FT_USPT - 1) / FT_USPT;
+
+	spin_lock_irq(&current->sighand->siglock);
+	old_sigmask = current->blocked;
+	sigfillset(&current->blocked);
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+
+	set_current_state(TASK_INTERRUPTIBLE);
+	add_wait_queue(&ftape_wait_intr, &wait);
+	while (!ft_interrupt_seen && timeout) {
+		set_current_state(TASK_INTERRUPTIBLE);
+		timeout = schedule_timeout(timeout);
+        }
+
+	spin_lock_irq(&current->sighand->siglock);
+	current->blocked = old_sigmask;
+	recalc_sigpending();
+	spin_unlock_irq(&current->sighand->siglock);
+	
+	remove_wait_queue(&ftape_wait_intr, &wait);
+	/*  the following IS necessary. True: as well
+	 *  wake_up_interruptible() as the schedule() set TASK_RUNNING
+	 *  when they wakeup a task, BUT: it may very well be that
+	 *  ft_interrupt_seen is already set to 1 when we enter here
+	 *  in which case schedule() gets never called, and
+	 *  TASK_RUNNING never set. This has the funny effect that we
+	 *  execute all the code until we leave kernel space, but then
+	 *  the task is stopped (a task CANNOT be preempted while in
+	 *  kernel mode. Sending a pair of SIGSTOP/SIGCONT to the
+	 *  tasks wakes it up again. Funny! :-)
+	 */
+	current->state = TASK_RUNNING; 
+	if (ft_interrupt_seen) { /* woken up by interrupt */
+		ft_interrupt_seen = 0;
+		TRACE_EXIT 0;
+	}
+	/*  Original comment:
+	 *  In first instance, next statement seems unnecessary since
+	 *  it will be cleared in fdc_command. However, a small part of
+	 *  the software seems to rely on this being cleared here
+	 *  (ftape_close might fail) so stick to it until things get fixed !
+	 */
+	/*  My deeply sought of knowledge:
+	 *  Behold NO! It is obvious. fdc_reset() doesn't call fdc_command()
+	 *  but nevertheless uses fdc_interrupt_wait(). OF COURSE this needs to
+	 *  be reset here.
+	 */
+	ft_interrupt_seen = 0;	/* clear for next call */
+	if (!resetting) {
+		resetting = 1;	/* break infinite recursion if reset fails */
+		TRACE(ft_t_any, "cleanup reset");
+		fdc_reset();
+		resetting = 0;
+	}
+	TRACE_EXIT (signal_pending(current)) ? -EINTR : -ETIME;
+}
+
+/*      Start/stop drive motor. Enable DMA mode.
+ */
+void fdc_motor(int motor)
+{
+	int unit = ft_drive_sel;
+	int data = unit | FDC_RESET_NOT | FDC_DMA_MODE;
+	TRACE_FUN(ft_t_any);
+
+	ftape_motor = motor;
+	if (ftape_motor) {
+		data |= FDC_MOTOR_0 << unit;
+		TRACE(ft_t_noise, "turning motor %d on", unit);
+	} else {
+		TRACE(ft_t_noise, "turning motor %d off", unit);
+	}
+	if (ft_mach2) {
+		outb_p(data, fdc.dor2);
+	} else {
+		outb_p(data, fdc.dor);
+	}
+	ftape_sleep(10 * FT_MILLISECOND);
+	TRACE_EXIT;
+}
+
+static void fdc_update_dsr(void)
+{
+	TRACE_FUN(ft_t_any);
+
+	TRACE(ft_t_flow, "rate = %d Kbps, precomp = %d ns",
+	      fdc_data_rate, fdc_precomp);
+	if (fdc.type >= i82077) {
+		outb_p((fdc_rate_code & 0x03) | fdc_prec_code, fdc.dsr);
+	} else {
+		outb_p(fdc_rate_code & 0x03, fdc.ccr);
+	}
+	TRACE_EXIT;
+}
+
+void fdc_set_write_precomp(int precomp)
+{
+	TRACE_FUN(ft_t_any);
+
+	TRACE(ft_t_noise, "New precomp: %d nsec", precomp);
+	fdc_precomp = precomp;
+	/*  write precompensation can be set in multiples of 41.67 nsec.
+	 *  round the parameter to the nearest multiple and convert it
+	 *  into a fdc setting. Note that 0 means default to the fdc,
+	 *  7 is used instead of that.
+	 */
+	fdc_prec_code = ((fdc_precomp + 21) / 42) << 2;
+	if (fdc_prec_code == 0 || fdc_prec_code > (6 << 2)) {
+		fdc_prec_code = 7 << 2;
+	}
+	fdc_update_dsr();
+	TRACE_EXIT;
+}
+
+/*  Reprogram the 82078 registers to use Data Rate Table 1 on all drives.
+ */
+static void fdc_set_drive_specs(void)
+{
+	__u8 cmd[] = { FDC_DRIVE_SPEC, 0x00, 0x00, 0x00, 0x00, 0xc0};
+	int result;
+	TRACE_FUN(ft_t_any);
+
+	TRACE(ft_t_flow, "Setting of drive specs called");
+	if (fdc.type >= i82078_1) {
+		cmd[1] = (0 << 5) | (2 << 2);
+		cmd[2] = (1 << 5) | (2 << 2);
+		cmd[3] = (2 << 5) | (2 << 2);
+		cmd[4] = (3 << 5) | (2 << 2);
+		result = fdc_command(cmd, NR_ITEMS(cmd));
+		if (result < 0) {
+			TRACE(ft_t_err, "Setting of drive specs failed");
+		}
+	}
+	TRACE_EXIT;
+}
+
+/* Select clock for fdc, must correspond with tape drive setting !
+ * This also influences the fdc timing so we must adjust some values.
+ */
+int fdc_set_data_rate(int rate)
+{
+	int bad_rate = 0;
+	TRACE_FUN(ft_t_any);
+
+	/* Select clock for fdc, must correspond with tape drive setting !
+	 * This also influences the fdc timing so we must adjust some values.
+	 */
+	TRACE(ft_t_fdc_dma, "new rate = %d", rate);
+	switch (rate) {
+	case 250:
+		fdc_rate_code = fdc_data_rate_250;
+		break;
+	case 500:
+		fdc_rate_code = fdc_data_rate_500;
+		break;
+	case 1000:
+		if (fdc.type < i82077) {
+			bad_rate = 1;
+                } else {
+			fdc_rate_code = fdc_data_rate_1000;
+		}
+		break;
+	case 2000:
+		if (fdc.type < i82078_1) {
+			bad_rate = 1;
+                } else {
+			fdc_rate_code = fdc_data_rate_2000;
+		}
+		break;
+	default:
+		bad_rate = 1;
+        }
+	if (bad_rate) {
+		TRACE_ABORT(-EIO,
+			    ft_t_fdc_dma, "%d is not a valid data rate", rate);
+	}
+	fdc_data_rate = rate;
+	fdc_update_dsr();
+	fdc_set_seek_rate(fdc_seek_rate);  /* clock changed! */
+	ftape_udelay(1000);
+	TRACE_EXIT 0;
+}
+
+/*  keep the unit select if keep_select is != 0,
+ */
+static void fdc_dor_reset(int keep_select)
+{
+	__u8 fdc_ctl = ft_drive_sel;
+
+	if (keep_select != 0) {
+		fdc_ctl |= FDC_DMA_MODE;
+		if (ftape_motor) {
+			fdc_ctl |= FDC_MOTOR_0 << ft_drive_sel;
+		}
+	}
+	ftape_udelay(10); /* ??? but seems to be necessary */
+	if (ft_mach2) {
+		outb_p(fdc_ctl & 0x0f, fdc.dor);
+		outb_p(fdc_ctl, fdc.dor2);
+	} else {
+		outb_p(fdc_ctl, fdc.dor);
+	}
+	fdc_usec_wait(10); /* delay >= 14 fdc clocks */
+	if (keep_select == 0) {
+		fdc_ctl = 0;
+	}
+	fdc_ctl |= FDC_RESET_NOT;
+	if (ft_mach2) {
+		outb_p(fdc_ctl & 0x0f, fdc.dor);
+		outb_p(fdc_ctl, fdc.dor2);
+	} else {
+		outb_p(fdc_ctl, fdc.dor);
+	}
+}
+
+/*      Reset the floppy disk controller. Leave the ftape_unit selected.
+ */
+void fdc_reset(void)
+{
+	int st0;
+	int i;
+	int dummy;
+	unsigned long flags;
+	TRACE_FUN(ft_t_any);
+
+	spin_lock_irqsave(&fdc_io_lock, flags);
+
+	fdc_dor_reset(1); /* keep unit selected */
+
+	fdc_mode = fdc_idle;
+
+	/*  maybe the cli()/sti() pair is not necessary, BUT:
+	 *  the following line MUST be here. Otherwise fdc_interrupt_wait()
+	 *  won't wait. Note that fdc_reset() is called from 
+	 *  ftape_dumb_stop() when the fdc is busy transferring data. In this
+	 *  case fdc_isr() MOST PROBABLY sets ft_interrupt_seen, and tries
+	 *  to get the result bytes from the fdc etc. CLASH.
+	 */
+	ft_interrupt_seen = 0;
+	
+	/*  Program data rate
+	 */
+	fdc_update_dsr();               /* restore data rate and precomp */
+
+	spin_unlock_irqrestore(&fdc_io_lock, flags);
+
+        /*
+         *	Wait for first polling cycle to complete
+	 */
+	if (fdc_interrupt_wait(1 * FT_SECOND) < 0) {
+		TRACE(ft_t_err, "no drive polling interrupt!");
+	} else {	/* clear all disk-changed statuses */
+		for (i = 0; i < 4; ++i) {
+			if(fdc_sense_interrupt_status(&st0, &dummy) != 0) {
+				TRACE(ft_t_err, "sense failed for %d", i);
+			}
+			if (i == ft_drive_sel) {
+				ftape_current_cylinder = dummy;
+			}
+		}
+		TRACE(ft_t_noise, "drive polling completed");
+	}
+	/*
+         *	SPECIFY COMMAND
+	 */
+	fdc_set_seek_rate(fdc_seek_rate);
+	/*
+	 *	DRIVE SPECIFICATION COMMAND (if fdc type known)
+	 */
+	if (fdc.type >= i82078_1) {
+		fdc_set_drive_specs();
+	}
+	TRACE_EXIT;
+}
+
+#if !defined(CLK_48MHZ)
+# define CLK_48MHZ 1
+#endif
+
+/*  When we're done, put the fdc into reset mode so that the regular
+ *  floppy disk driver will figure out that something is wrong and
+ *  initialize the controller the way it wants.
+ */
+void fdc_disable(void)
+{
+	__u8 cmd1[] = {FDC_CONFIGURE, 0x00, 0x00, 0x00};
+	__u8 cmd2[] = {FDC_LOCK};
+	__u8 cmd3[] = {FDC_UNLOCK};
+	__u8 stat[1];
+	TRACE_FUN(ft_t_flow);
+
+	if (!fdc_fifo_locked) {
+		fdc_reset();
+		TRACE_EXIT;
+	}
+	if (fdc_issue_command(cmd3, 1, stat, 1) < 0 || stat[0] != 0x00) {
+		fdc_dor_reset(0);
+		TRACE_ABORT(/**/, ft_t_bug, 
+		"couldn't unlock fifo, configuration remains changed");
+	}
+	fdc_fifo_locked = 0;
+	if (CLK_48MHZ && fdc.type >= i82078) {
+		cmd1[0] |= FDC_CLK48_BIT;
+	}
+	cmd1[2] = ((fdc_fifo_state) ? 0 : 0x20) + (fdc_fifo_thr - 1);
+	if (fdc_command(cmd1, NR_ITEMS(cmd1)) < 0) {
+		fdc_dor_reset(0);
+		TRACE_ABORT(/**/, ft_t_bug,
+		"couldn't reconfigure fifo to old state");
+	}
+	if (fdc_lock_state &&
+	    fdc_issue_command(cmd2, 1, stat, 1) < 0) {
+		fdc_dor_reset(0);
+		TRACE_ABORT(/**/, ft_t_bug, "couldn't lock old state again");
+	}
+	TRACE(ft_t_noise, "fifo restored: %sabled, thr. %d, %slocked",
+	      fdc_fifo_state ? "en" : "dis",
+	      fdc_fifo_thr, (fdc_lock_state) ? "" : "not ");
+	fdc_dor_reset(0);
+	TRACE_EXIT;
+}
+
+/*      Specify FDC seek-rate (milliseconds)
+ */
+static int fdc_set_seek_rate(int seek_rate)
+{
+	/* set step rate, dma mode, and minimal head load and unload times
+	 */
+	__u8 in[3] = { FDC_SPECIFY, 1, (1 << 1)};
+ 
+	fdc_seek_rate = seek_rate;
+	in[1] |= (16 - (fdc_data_rate * fdc_seek_rate) / 500) << 4;
+
+	return fdc_command(in, 3);
+}
+
+/*      Sense drive status: get unit's drive status (ST3)
+ */
+int fdc_sense_drive_status(int *st3)
+{
+	__u8 out[2];
+	__u8 in[1];
+	TRACE_FUN(ft_t_any);
+
+	out[0] = FDC_SENSED;
+	out[1] = ft_drive_sel;
+	TRACE_CATCH(fdc_issue_command(out, 2, in, 1),);
+	*st3 = in[0];
+	TRACE_EXIT 0;
+}
+
+/*      Sense Interrupt Status command:
+ *      should be issued at the end of each seek.
+ *      get ST0 and current cylinder.
+ */
+int fdc_sense_interrupt_status(int *st0, int *current_cylinder)
+{
+	__u8 out[1];
+	__u8 in[2];
+	TRACE_FUN(ft_t_any);
+
+	out[0] = FDC_SENSEI;
+	TRACE_CATCH(fdc_issue_command(out, 1, in, 2),);
+	*st0 = in[0];
+	*current_cylinder = in[1];
+	TRACE_EXIT 0;
+}
+
+/*      step to track
+ */
+int fdc_seek(int track)
+{
+	__u8 out[3];
+	int st0, pcn;
+#ifdef TESTING
+	unsigned int time;
+#endif
+	TRACE_FUN(ft_t_any);
+
+	out[0] = FDC_SEEK;
+	out[1] = ft_drive_sel;
+	out[2] = track;
+#ifdef TESTING
+	time = ftape_timestamp();
+#endif
+	/*  We really need this command to work !
+	 */
+	ft_seek_completed = 0;
+	TRACE_CATCH(fdc_command(out, 3),
+		    fdc_reset();
+		    TRACE(ft_t_noise, "destination was: %d, resetting FDC...",
+			  track));
+	/*    Handle interrupts until ft_seek_completed or timeout.
+	 */
+	for (;;) {
+		TRACE_CATCH(fdc_interrupt_wait(2 * FT_SECOND),);
+		if (ft_seek_completed) {
+			TRACE_CATCH(fdc_sense_interrupt_status(&st0, &pcn),);
+			if ((st0 & ST0_SEEK_END) == 0) {
+				TRACE_ABORT(-EIO, ft_t_err,
+				      "no seek-end after seek completion !??");
+			}
+			break;
+		}
+	}
+#ifdef TESTING
+	time = ftape_timediff(time, ftape_timestamp()) / abs(track - ftape_current_cylinder);
+	if ((time < 900 || time > 3100) && abs(track - ftape_current_cylinder) > 5) {
+		TRACE(ft_t_warn, "Wrong FDC STEP interval: %d usecs (%d)",
+                         time, track - ftape_current_cylinder);
+	}
+#endif
+	/*    Verify whether we issued the right tape command.
+	 */
+	/* Verify that we seek to the proper track. */
+	if (pcn != track) {
+		TRACE_ABORT(-EIO, ft_t_err, "bad seek..");
+	}
+	ftape_current_cylinder = track;
+	TRACE_EXIT 0;
+}
+
+static int perpend_mode; /* set if fdc is in perpendicular mode */
+
+static int perpend_off(void)
+{
+ 	__u8 perpend[] = {FDC_PERPEND, 0x00};
+	TRACE_FUN(ft_t_any);
+	
+	if (perpend_mode) {
+		/* Turn off perpendicular mode */
+		perpend[1] = 0x80;
+		TRACE_CATCH(fdc_command(perpend, 2),
+			    TRACE(ft_t_err,"Perpendicular mode exit failed!"));
+		perpend_mode = 0;
+	}
+	TRACE_EXIT 0;
+}
+
+static int handle_perpend(int segment_id)
+{
+ 	__u8 perpend[] = {FDC_PERPEND, 0x00};
+	TRACE_FUN(ft_t_any);
+
+	/* When writing QIC-3020 tapes, turn on perpendicular mode
+	 * if tape is moving in forward direction (even tracks).
+	 */
+	if (ft_qic_std == QIC_TAPE_QIC3020 &&
+	    ((segment_id / ft_segments_per_track) & 1) == 0) {
+/*  FIXME: some i82077 seem to support perpendicular mode as
+ *  well. 
+ */
+#if 0
+		if (fdc.type < i82077AA) {}
+#else
+		if (fdc.type < i82077 && ft_data_rate < 1000) {
+#endif
+			/*  fdc does not support perpendicular mode: complain 
+			 */
+			TRACE_ABORT(-EIO, ft_t_err,
+				    "Your FDC does not support QIC-3020.");
+		}
+		perpend[1] = 0x03 /* 0x83 + (0x4 << ft_drive_sel) */ ;
+		TRACE_CATCH(fdc_command(perpend, 2),
+			   TRACE(ft_t_err,"Perpendicular mode entry failed!"));
+		TRACE(ft_t_flow, "Perpendicular mode set");
+		perpend_mode = 1;
+		TRACE_EXIT 0;
+	}
+	TRACE_EXIT perpend_off();
+}
+
+static inline void fdc_setup_dma(char mode,
+				 volatile void *addr, unsigned int count)
+{
+	/* Program the DMA controller.
+	 */
+	disable_dma(fdc.dma);
+	clear_dma_ff(fdc.dma);
+	set_dma_mode(fdc.dma, mode);
+	set_dma_addr(fdc.dma, virt_to_bus((void*)addr));
+	set_dma_count(fdc.dma, count);
+	enable_dma(fdc.dma);
+}
+
+/*  Setup fdc and dma for formatting the next segment
+ */
+int fdc_setup_formatting(buffer_struct * buff)
+{
+	unsigned long flags;
+	__u8 out[6] = {
+		FDC_FORMAT, 0x00, 3, 4 * FT_SECTORS_PER_SEGMENT, 0x00, 0x6b
+	};
+	TRACE_FUN(ft_t_any);
+	
+	TRACE_CATCH(handle_perpend(buff->segment_id),);
+	/* Program the DMA controller.
+	 */
+        TRACE(ft_t_fdc_dma,
+	      "phys. addr. = %lx", virt_to_bus((void*) buff->ptr));
+	spin_lock_irqsave(&fdc_io_lock, flags);
+	fdc_setup_dma(DMA_MODE_WRITE, buff->ptr, FT_SECTORS_PER_SEGMENT * 4);
+	/* Issue FDC command to start reading/writing.
+	 */
+	out[1] = ft_drive_sel;
+	out[4] = buff->gap3;
+	TRACE_CATCH(fdc_setup_error = fdc_command(out, sizeof(out)),
+		    restore_flags(flags); fdc_mode = fdc_idle);
+	spin_unlock_irqrestore(&fdc_io_lock, flags);
+	TRACE_EXIT 0;
+}
+
+
+/*      Setup Floppy Disk Controller and DMA to read or write the next cluster
+ *      of good sectors from or to the current segment.
+ */
+int fdc_setup_read_write(buffer_struct * buff, __u8 operation)
+{
+	unsigned long flags;
+	__u8 out[9];
+	int dma_mode;
+	TRACE_FUN(ft_t_any);
+
+	switch(operation) {
+	case FDC_VERIFY:
+		if (fdc.type < i82077) {
+			operation = FDC_READ;
+		}
+	case FDC_READ:
+	case FDC_READ_DELETED:
+		dma_mode = DMA_MODE_READ;
+		TRACE(ft_t_fdc_dma, "xfer %d sectors to 0x%p",
+		      buff->sector_count, buff->ptr);
+		TRACE_CATCH(perpend_off(),);
+		break;
+	case FDC_WRITE_DELETED:
+		TRACE(ft_t_noise, "deleting segment %d", buff->segment_id);
+	case FDC_WRITE:
+		dma_mode = DMA_MODE_WRITE;
+		/* When writing QIC-3020 tapes, turn on perpendicular mode
+		 * if tape is moving in forward direction (even tracks).
+		 */
+		TRACE_CATCH(handle_perpend(buff->segment_id),);
+		TRACE(ft_t_fdc_dma, "xfer %d sectors from 0x%p",
+		      buff->sector_count, buff->ptr);
+		break;
+	default:
+		TRACE_ABORT(-EIO,
+			    ft_t_bug, "bug: invalid operation parameter");
+	}
+	TRACE(ft_t_fdc_dma, "phys. addr. = %lx",virt_to_bus((void*)buff->ptr));
+	spin_lock_irqsave(&fdc_io_lock, flags);
+	if (operation != FDC_VERIFY) {
+		fdc_setup_dma(dma_mode, buff->ptr,
+			      FT_SECTOR_SIZE * buff->sector_count);
+	}
+	/* Issue FDC command to start reading/writing.
+	 */
+	out[0] = operation;
+	out[1] = ft_drive_sel;
+	out[2] = buff->cyl;
+	out[3] = buff->head;
+	out[4] = buff->sect + buff->sector_offset;
+	out[5] = 3;		/* Sector size of 1K. */
+	out[6] = out[4] + buff->sector_count - 1;	/* last sector */
+	out[7] = 109;		/* Gap length. */
+	out[8] = 0xff;		/* No limit to transfer size. */
+	TRACE(ft_t_fdc_dma, "C: 0x%02x, H: 0x%02x, R: 0x%02x, cnt: 0x%02x",
+		out[2], out[3], out[4], out[6] - out[4] + 1);
+	spin_unlock_irqrestore(&fdc_io_lock, flags);
+	TRACE_CATCH(fdc_setup_error = fdc_command(out, 9),fdc_mode = fdc_idle);
+	TRACE_EXIT 0;
+}
+
+int fdc_fifo_threshold(__u8 threshold,
+		       int *fifo_state, int *lock_state, int *fifo_thr)
+{
+	const __u8 cmd0[] = {FDC_DUMPREGS};
+	__u8 cmd1[] = {FDC_CONFIGURE, 0, (0x0f & (threshold - 1)), 0};
+	const __u8 cmd2[] = {FDC_LOCK};
+	const __u8 cmd3[] = {FDC_UNLOCK};
+	__u8 reg[10];
+	__u8 stat;
+	int i;
+	int result;
+	TRACE_FUN(ft_t_any);
+
+	if (CLK_48MHZ && fdc.type >= i82078) {
+		cmd1[0] |= FDC_CLK48_BIT;
+	}
+	/*  Dump fdc internal registers for examination
+	 */
+	TRACE_CATCH(fdc_command(cmd0, NR_ITEMS(cmd0)),
+		    TRACE(ft_t_warn, "dumpreg cmd failed, fifo unchanged"));
+	/*  Now read fdc internal registers from fifo
+	 */
+	for (i = 0; i < (int)NR_ITEMS(reg); ++i) {
+		fdc_read(&reg[i]);
+		TRACE(ft_t_fdc_dma, "Register %d = 0x%02x", i, reg[i]);
+	}
+	if (fifo_state && lock_state && fifo_thr) {
+		*fifo_state = (reg[8] & 0x20) == 0;
+		*lock_state = reg[7] & 0x80;
+		*fifo_thr = 1 + (reg[8] & 0x0f);
+	}
+	TRACE(ft_t_noise,
+	      "original fifo state: %sabled, threshold %d, %slocked",
+	      ((reg[8] & 0x20) == 0) ? "en" : "dis",
+	      1 + (reg[8] & 0x0f), (reg[7] & 0x80) ? "" : "not ");
+	/*  If fdc is already locked, unlock it first ! */
+	if (reg[7] & 0x80) {
+		fdc_ready_wait(100);
+		TRACE_CATCH(fdc_issue_command(cmd3, NR_ITEMS(cmd3), &stat, 1),
+			    TRACE(ft_t_bug, "FDC unlock command failed, "
+				  "configuration unchanged"));
+	}
+	fdc_fifo_locked = 0;
+	/*  Enable fifo and set threshold at xx bytes to allow a
+	 *  reasonably large latency and reduce number of dma bursts.
+	 */
+	fdc_ready_wait(100);
+	if ((result = fdc_command(cmd1, NR_ITEMS(cmd1))) < 0) {
+		TRACE(ft_t_bug, "configure cmd failed, fifo unchanged");
+	}
+	/*  Now lock configuration so reset will not change it
+	 */
+        if(fdc_issue_command(cmd2, NR_ITEMS(cmd2), &stat, 1) < 0 ||
+	   stat != 0x10) {
+		TRACE_ABORT(-EIO, ft_t_bug,
+			    "FDC lock command failed, stat = 0x%02x", stat);
+	}
+	fdc_fifo_locked = 1;
+	TRACE_EXIT result;
+}
+
+static int fdc_fifo_enable(void)
+{
+	TRACE_FUN(ft_t_any);
+
+	if (fdc_fifo_locked) {
+		TRACE_ABORT(0, ft_t_warn, "Fifo not enabled because locked");
+	}
+	TRACE_CATCH(fdc_fifo_threshold(ft_fdc_threshold /* bytes */,
+				       &fdc_fifo_state,
+				       &fdc_lock_state,
+				       &fdc_fifo_thr),);
+	TRACE_CATCH(fdc_fifo_threshold(ft_fdc_threshold /* bytes */,
+				       NULL, NULL, NULL),);
+	TRACE_EXIT 0;
+}
+
+/*   Determine fd controller type 
+ */
+static __u8 fdc_save_state[2];
+
+static int fdc_probe(void)
+{
+	__u8 cmd[1];
+	__u8 stat[16]; /* must be able to hold dumpregs & save results */
+	int i;
+	TRACE_FUN(ft_t_any);
+
+	/*  Try to find out what kind of fd controller we have to deal with
+	 *  Scheme borrowed from floppy driver:
+	 *  first try if FDC_DUMPREGS command works
+	 *  (this indicates that we have a 82072 or better)
+	 *  then try the FDC_VERSION command (82072 doesn't support this)
+	 *  then try the FDC_UNLOCK command (some older 82077's don't support this)
+	 *  then try the FDC_PARTID command (82078's support this)
+	 */
+	cmd[0] = FDC_DUMPREGS;
+	if (fdc_issue_command(cmd, 1, stat, 1) != 0) {
+		TRACE_ABORT(no_fdc, ft_t_bug, "No FDC found");
+	}
+	if (stat[0] == 0x80) {
+		/* invalid command: must be pre 82072 */
+		TRACE_ABORT(i8272,
+			    ft_t_warn, "Type 8272A/765A compatible FDC found");
+	}
+	fdc_result(&stat[1], 9);
+	fdc_save_state[0] = stat[7];
+	fdc_save_state[1] = stat[8];
+	cmd[0] = FDC_VERSION;
+	if (fdc_issue_command(cmd, 1, stat, 1) < 0 || stat[0] == 0x80) {
+		TRACE_ABORT(i8272, ft_t_warn, "Type 82072 FDC found");
+	}
+	if (*stat != 0x90) {
+		TRACE_ABORT(i8272, ft_t_warn, "Unknown FDC found");
+	}
+	cmd[0] = FDC_UNLOCK;
+	if(fdc_issue_command(cmd, 1, stat, 1) < 0 || stat[0] != 0x00) {
+		TRACE_ABORT(i8272, ft_t_warn,
+			    "Type pre-1991 82077 FDC found, "
+			    "treating it like a 82072");
+	}
+	if (fdc_save_state[0] & 0x80) { /* was locked */
+		cmd[0] = FDC_LOCK; /* restore lock */
+		(void)fdc_issue_command(cmd, 1, stat, 1);
+		TRACE(ft_t_warn, "FDC is already locked");
+	}
+	/* Test for a i82078 FDC */
+	cmd[0] = FDC_PARTID;
+	if (fdc_issue_command(cmd, 1, stat, 1) < 0 || stat[0] == 0x80) {
+		/* invalid command: not a i82078xx type FDC */
+		for (i = 0; i < 4; ++i) {
+			outb_p(i, fdc.tdr);
+			if ((inb_p(fdc.tdr) & 0x03) != i) {
+				TRACE_ABORT(i82077,
+					    ft_t_warn, "Type 82077 FDC found");
+			}
+		}
+		TRACE_ABORT(i82077AA, ft_t_warn, "Type 82077AA FDC found");
+	}
+	/* FDC_PARTID cmd succeeded */
+	switch (stat[0] >> 5) {
+	case 0x0:
+		/* i82078SL or i82078-1.  The SL part cannot run at
+		 * 2Mbps (the SL and -1 dies are identical; they are
+		 * speed graded after production, according to Intel).
+		 * Some SL's can be detected by doing a SAVE cmd and
+		 * look at bit 7 of the first byte (the SEL3V# bit).
+		 * If it is 0, the part runs off 3Volts, and hence it
+		 * is a SL.
+		 */
+		cmd[0] = FDC_SAVE;
+		if(fdc_issue_command(cmd, 1, stat, 16) < 0) {
+			TRACE(ft_t_err, "FDC_SAVE failed. Dunno why");
+			/* guess we better claim the fdc to be a i82078 */
+			TRACE_ABORT(i82078,
+				    ft_t_warn,
+				    "Type i82078 FDC (i suppose) found");
+		}
+		if ((stat[0] & FDC_SEL3V_BIT)) {
+			/* fdc running off 5Volts; Pray that it's a i82078-1
+			 */
+			TRACE_ABORT(i82078_1, ft_t_warn,
+				  "Type i82078-1 or 5Volt i82078SL FDC found");
+		}
+		TRACE_ABORT(i82078, ft_t_warn,
+			    "Type 3Volt i82078SL FDC (1Mbps) found");
+	case 0x1:
+	case 0x2: /* S82078B  */
+		/* The '78B  isn't '78 compatible.  Detect it as a '77AA */
+		TRACE_ABORT(i82077AA, ft_t_warn, "Type i82077AA FDC found");
+	case 0x3: /* NSC PC8744 core; used in several super-IO chips */
+		TRACE_ABORT(i82077AA,
+			    ft_t_warn, "Type 82077AA compatible FDC found");
+	default:
+		TRACE(ft_t_warn, "A previously undetected FDC found");
+		TRACE_ABORT(i82077AA, ft_t_warn,
+			  "Treating it as a 82077AA. Please report partid= %d",
+			    stat[0]);
+	} /* switch(stat[ 0] >> 5) */
+	TRACE_EXIT no_fdc;
+}
+
+static int fdc_request_regions(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (ft_mach2 || ft_probe_fc10) {
+		if (!request_region(fdc.sra, 8, "fdc (ft)")) {
+#ifndef BROKEN_FLOPPY_DRIVER
+			TRACE_EXIT -EBUSY;
+#else
+			TRACE(ft_t_warn,
+"address 0x%03x occupied (by floppy driver?), using it anyway", fdc.sra);
+#endif
+		}
+	} else {
+		if (!request_region(fdc.sra, 6, "fdc (ft)")) {
+#ifndef BROKEN_FLOPPY_DRIVER
+			TRACE_EXIT -EBUSY;
+#else
+			TRACE(ft_t_warn,
+"address 0x%03x occupied (by floppy driver?), using it anyway", fdc.sra);
+#endif
+		}
+		if (!request_region(fdc.sra + 7, 1, "fdc (ft)")) {
+#ifndef BROKEN_FLOPPY_DRIVER
+			release_region(fdc.sra, 6);
+			TRACE_EXIT -EBUSY;
+#else
+			TRACE(ft_t_warn,
+"address 0x%03x occupied (by floppy driver?), using it anyway", fdc.sra + 7);
+#endif
+		}
+	}
+	TRACE_EXIT 0;
+}
+
+void fdc_release_regions(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (fdc.sra != 0) {
+		if (fdc.dor2 != 0) {
+			release_region(fdc.sra, 8);
+		} else {
+			release_region(fdc.sra, 6);
+			release_region(fdc.dir, 1);
+		}
+	}
+	TRACE_EXIT;
+}
+
+static int fdc_config_regs(unsigned int fdc_base, 
+			   unsigned int fdc_irq, 
+			   unsigned int fdc_dma)
+{
+	TRACE_FUN(ft_t_flow);
+
+	fdc.irq = fdc_irq;
+	fdc.dma = fdc_dma;
+	fdc.sra = fdc_base;
+	fdc.srb = fdc_base + 1;
+	fdc.dor = fdc_base + 2;
+	fdc.tdr = fdc_base + 3;
+	fdc.msr = fdc.dsr = fdc_base + 4;
+	fdc.fifo = fdc_base + 5;
+	fdc.dir = fdc.ccr = fdc_base + 7;
+	fdc.dor2 = (ft_mach2 || ft_probe_fc10) ? fdc_base + 6 : 0;
+	TRACE_CATCH(fdc_request_regions(), fdc.sra = 0);
+	TRACE_EXIT 0;
+}
+
+static int fdc_config(void)
+{
+	static int already_done;
+	TRACE_FUN(ft_t_any);
+
+	if (already_done) {
+		TRACE_CATCH(fdc_request_regions(),);
+		*(fdc.hook) = fdc_isr;	/* hook our handler in */
+		TRACE_EXIT 0;
+	}
+	if (ft_probe_fc10) {
+		int fc_type;
+		
+		TRACE_CATCH(fdc_config_regs(ft_fdc_base,
+					    ft_fdc_irq, ft_fdc_dma),);
+		fc_type = fc10_enable();
+		if (fc_type != 0) {
+			TRACE(ft_t_warn, "FC-%c0 controller found", '0' + fc_type);
+			fdc.type = fc10;
+			fdc.hook = &do_ftape;
+			*(fdc.hook) = fdc_isr;	/* hook our handler in */
+			already_done = 1;
+			TRACE_EXIT 0;
+		} else {
+			TRACE(ft_t_warn, "FC-10/20 controller not found");
+			fdc_release_regions();
+			fdc.type = no_fdc;
+			ft_probe_fc10 = 0;
+			ft_fdc_base   = 0x3f0;
+			ft_fdc_irq    = 6;
+			ft_fdc_dma    = 2;
+		}
+	}
+	TRACE(ft_t_warn, "fdc base: 0x%x, irq: %d, dma: %d", 
+	      ft_fdc_base, ft_fdc_irq, ft_fdc_dma);
+	TRACE_CATCH(fdc_config_regs(ft_fdc_base, ft_fdc_irq, ft_fdc_dma),);
+	fdc.hook = &do_ftape;
+	*(fdc.hook) = fdc_isr;	/* hook our handler in */
+	already_done = 1;
+	TRACE_EXIT 0;
+}
+
+static irqreturn_t ftape_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+	void (*handler) (void) = *fdc.hook;
+	int handled = 0;
+	TRACE_FUN(ft_t_any);
+
+	*fdc.hook = NULL;
+	if (handler) {
+		handled = 1;
+		handler();
+	} else {
+		TRACE(ft_t_bug, "Unexpected ftape interrupt");
+	}
+	TRACE_EXIT IRQ_RETVAL(handled);
+}
+
+static int fdc_grab_irq_and_dma(void)
+{
+	TRACE_FUN(ft_t_any);
+
+	if (fdc.hook == &do_ftape) {
+		/*  Get fast interrupt handler.
+		 */
+		if (request_irq(fdc.irq, ftape_interrupt,
+				SA_INTERRUPT, "ft", ftape_id)) {
+			TRACE_ABORT(-EIO, ft_t_bug,
+				    "Unable to grab IRQ%d for ftape driver",
+				    fdc.irq);
+		}
+		if (request_dma(fdc.dma, ftape_id)) {
+			free_irq(fdc.irq, ftape_id);
+			TRACE_ABORT(-EIO, ft_t_bug,
+			      "Unable to grab DMA%d for ftape driver",
+			      fdc.dma);
+		}
+	}
+	if (ft_fdc_base != 0x3f0 && (ft_fdc_dma == 2 || ft_fdc_irq == 6)) {
+		/* Using same dma channel or irq as standard fdc, need
+		 * to disable the dma-gate on the std fdc. This
+		 * couldn't be done in the floppy driver as some
+		 * laptops are using the dma-gate to enter a low power
+		 * or even suspended state :-(
+		 */
+		outb_p(FDC_RESET_NOT, 0x3f2);
+		TRACE(ft_t_noise, "DMA-gate on standard fdc disabled");
+	}
+	TRACE_EXIT 0;
+}
+
+int fdc_release_irq_and_dma(void)
+{
+	TRACE_FUN(ft_t_any);
+
+	if (fdc.hook == &do_ftape) {
+		disable_dma(fdc.dma);	/* just in case... */
+		free_dma(fdc.dma);
+		free_irq(fdc.irq, ftape_id);
+	}
+	if (ft_fdc_base != 0x3f0 && (ft_fdc_dma == 2 || ft_fdc_irq == 6)) {
+		/* Using same dma channel as standard fdc, need to
+		 * disable the dma-gate on the std fdc. This couldn't
+		 * be done in the floppy driver as some laptops are
+		 * using the dma-gate to enter a low power or even
+		 * suspended state :-(
+		 */
+		outb_p(FDC_RESET_NOT | FDC_DMA_MODE, 0x3f2);
+		TRACE(ft_t_noise, "DMA-gate on standard fdc enabled again");
+	}
+	TRACE_EXIT 0;
+}
+
+int fdc_init(void)
+{
+	TRACE_FUN(ft_t_any);
+
+	/* find a FDC to use */
+	TRACE_CATCH(fdc_config(),);
+	TRACE_CATCH(fdc_grab_irq_and_dma(), fdc_release_regions());
+	ftape_motor = 0;
+	fdc_catch_stray_interrupts(0);	/* clear number of awainted
+					 * stray interrupte 
+					 */
+	fdc_catch_stray_interrupts(1);	/* one always comes (?) */
+	TRACE(ft_t_flow, "resetting fdc");
+	fdc_set_seek_rate(2);		/* use nominal QIC step rate */
+	fdc_reset();			/* init fdc & clear track counters */
+	if (fdc.type == no_fdc) {	/* no FC-10 or FC-20 found */
+		fdc.type = fdc_probe();
+		fdc_reset();		/* update with new knowledge */
+	}
+	if (fdc.type == no_fdc) {
+		fdc_release_irq_and_dma();
+		fdc_release_regions();
+		TRACE_EXIT -ENXIO;
+	}
+	if (fdc.type >= i82077) {
+		if (fdc_fifo_enable() < 0) {
+			TRACE(ft_t_warn, "couldn't enable fdc fifo !");
+		} else {
+			TRACE(ft_t_flow, "fdc fifo enabled and locked");
+		}
+	}
+	TRACE_EXIT 0;
+}
diff --git a/drivers/char/ftape/lowlevel/fdc-io.h b/drivers/char/ftape/lowlevel/fdc-io.h
new file mode 100644
index 0000000..7ec3c72
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/fdc-io.h
@@ -0,0 +1,252 @@
+#ifndef _FDC_IO_H
+#define _FDC_IO_H
+
+/*
+ *    Copyright (C) 1993-1996 Bas Laarhoven,
+ *              (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/fdc-io.h,v $
+ * $Revision: 1.3 $
+ * $Date: 1997/10/05 19:18:06 $
+ *
+ *      This file contains the declarations for the low level
+ *      functions that communicate with the floppy disk controller,
+ *      for the QIC-40/80/3010/3020 floppy-tape driver "ftape" for
+ *      Linux.
+ */
+
+#include <linux/fdreg.h>
+
+#include "../lowlevel/ftape-bsm.h"
+
+#define FDC_SK_BIT      (0x20)
+#define FDC_MT_BIT      (0x80)
+
+#define FDC_READ        (FD_READ & ~(FDC_SK_BIT | FDC_MT_BIT))
+#define FDC_WRITE       (FD_WRITE & ~FDC_MT_BIT)
+#define FDC_READ_DELETED  (0x4c)
+#define FDC_WRITE_DELETED (0x49)
+#define FDC_VERIFY        (0x56)
+#define FDC_READID      (0x4a)
+#define FDC_SENSED      (0x04)
+#define FDC_SENSEI      (FD_SENSEI)
+#define FDC_FORMAT      (FD_FORMAT)
+#define FDC_RECAL       (FD_RECALIBRATE)
+#define FDC_SEEK        (FD_SEEK)
+#define FDC_SPECIFY     (FD_SPECIFY)
+#define FDC_RECALIBR    (FD_RECALIBRATE)
+#define FDC_VERSION     (FD_VERSION)
+#define FDC_PERPEND     (FD_PERPENDICULAR)
+#define FDC_DUMPREGS    (FD_DUMPREGS)
+#define FDC_LOCK        (FD_LOCK)
+#define FDC_UNLOCK      (FD_UNLOCK)
+#define FDC_CONFIGURE   (FD_CONFIGURE)
+#define FDC_DRIVE_SPEC  (0x8e)	/* i82078 has this (any others?) */
+#define FDC_PARTID      (0x18)	/* i82078 has this */
+#define FDC_SAVE        (0x2e)	/* i82078 has this (any others?) */
+#define FDC_RESTORE     (0x4e)	/* i82078 has this (any others?) */
+
+#define FDC_STATUS_MASK (STATUS_BUSY | STATUS_DMA | STATUS_DIR | STATUS_READY)
+#define FDC_DATA_READY  (STATUS_READY)
+#define FDC_DATA_OUTPUT (STATUS_DIR)
+#define FDC_DATA_READY_MASK (STATUS_READY | STATUS_DIR)
+#define FDC_DATA_OUT_READY  (STATUS_READY | STATUS_DIR)
+#define FDC_DATA_IN_READY   (STATUS_READY)
+#define FDC_BUSY        (STATUS_BUSY)
+#define FDC_CLK48_BIT   (0x80)
+#define FDC_SEL3V_BIT   (0x40)
+
+#define ST0_INT_MASK    (ST0_INTR)
+#define FDC_INT_NORMAL  (ST0_INTR & 0x00)
+#define FDC_INT_ABNORMAL (ST0_INTR & 0x40)
+#define FDC_INT_INVALID (ST0_INTR & 0x80)
+#define FDC_INT_READYCH (ST0_INTR & 0xC0)
+#define ST0_SEEK_END    (ST0_SE)
+#define ST3_TRACK_0     (ST3_TZ)
+
+#define FDC_RESET_NOT   (0x04)
+#define FDC_DMA_MODE    (0x08)
+#define FDC_MOTOR_0     (0x10)
+#define FDC_MOTOR_1     (0x20)
+
+typedef struct {
+	void (**hook) (void);	/* our wedge into the isr */
+	enum {
+		no_fdc, i8272, i82077, i82077AA, fc10,
+		i82078, i82078_1
+	} type;			/* FDC type */
+	unsigned int irq; /* FDC irq nr */
+	unsigned int dma; /* FDC dma channel nr */
+	__u16 sra;	  /* Status register A (PS/2 only) */
+	__u16 srb;	  /* Status register B (PS/2 only) */
+	__u16 dor;	  /* Digital output register */
+	__u16 tdr;	  /* Tape Drive Register (82077SL-1 &
+			     82078 only) */
+	__u16 msr;	  /* Main Status Register */
+	__u16 dsr;	  /* Datarate Select Register (8207x only) */
+	__u16 fifo;	  /* Data register / Fifo on 8207x */
+	__u16 dir;	  /* Digital Input Register */
+	__u16 ccr;	  /* Configuration Control Register */
+	__u16 dor2;	  /* Alternate dor on MACH-2 controller,
+			     also used with FC-10, meaning unknown */
+} fdc_config_info;
+
+typedef enum {
+	fdc_data_rate_250  = 2,
+	fdc_data_rate_300  = 1,	/* any fdc in default configuration */
+	fdc_data_rate_500  = 0,
+	fdc_data_rate_1000 = 3,
+	fdc_data_rate_2000 = 1,	/* i82078-1: when using Data Rate Table #2 */
+} fdc_data_rate_type;
+
+typedef enum {
+	fdc_idle          = 0,
+	fdc_reading_data  = FDC_READ,
+	fdc_seeking       = FDC_SEEK,
+	fdc_writing_data  = FDC_WRITE,
+	fdc_deleting      = FDC_WRITE_DELETED,
+	fdc_reading_id    = FDC_READID,
+	fdc_recalibrating = FDC_RECAL,
+	fdc_formatting    = FDC_FORMAT,
+	fdc_verifying     = FDC_VERIFY
+} fdc_mode_enum;
+
+typedef enum {
+	waiting = 0,
+	reading,
+	writing,
+	formatting,
+	verifying,
+	deleting,
+	done,
+	error,
+	mmapped,
+} buffer_state_enum;
+
+typedef struct {
+	__u8 *address;
+	volatile buffer_state_enum status;
+	volatile __u8 *ptr;
+	volatile unsigned int bytes;
+	volatile unsigned int segment_id;
+
+	/* bitmap for remainder of segment not yet handled.
+	 * one bit set for each bad sector that must be skipped.
+	 */
+	volatile SectorMap bad_sector_map;
+
+	/* bitmap with bad data blocks in data buffer.
+	 * the errors in this map may be retried.
+	 */
+	volatile SectorMap soft_error_map;
+
+	/* bitmap with bad data blocks in data buffer
+	 * the errors in this map may not be retried.
+	 */
+	volatile SectorMap hard_error_map;
+
+	/* retry counter for soft errors.
+	 */
+	volatile int retry;
+
+	/* sectors to skip on retry ???
+	 */
+	volatile unsigned int skip;
+
+	/* nr of data blocks in data buffer
+	 */
+	volatile unsigned int data_offset;
+
+	/* offset in segment for first sector to be handled.
+	 */
+	volatile unsigned int sector_offset;
+
+	/* size of cluster of good sectors to be handled.
+	 */
+	volatile unsigned int sector_count;
+
+	/* size of remaining part of segment to be handled.
+	 */
+	volatile unsigned int remaining;
+
+	/* points to next segment (contiguous) to be handled,
+	 * or is zero if no read-ahead is allowed.
+	 */
+	volatile unsigned int next_segment;
+
+	/* flag being set if deleted data was read.
+	 */
+	volatile int deleted;
+
+	/* floppy coordinates of first sector in segment */
+	volatile __u8 head;
+	volatile __u8 cyl;
+	volatile __u8 sect;
+
+	/* gap to use when formatting */
+	__u8 gap3;
+	/* flag set when buffer is mmaped */
+	int mmapped;
+} buffer_struct;
+
+/*
+ *      fdc-io.c defined public variables
+ */
+extern volatile fdc_mode_enum fdc_mode;
+extern int fdc_setup_error;	/* outdated ??? */
+extern wait_queue_head_t ftape_wait_intr;
+extern volatile int ftape_current_cylinder; /* track nr FDC thinks we're on */
+extern volatile __u8 fdc_head;	/* FDC head */
+extern volatile __u8 fdc_cyl;	/* FDC track */
+extern volatile __u8 fdc_sect;	/* FDC sector */
+extern fdc_config_info fdc;	/* FDC hardware configuration */
+
+extern unsigned int ft_fdc_base;
+extern unsigned int ft_fdc_irq;
+extern unsigned int ft_fdc_dma;
+extern unsigned int ft_fdc_threshold;
+extern unsigned int ft_fdc_rate_limit;
+extern int ft_probe_fc10;
+extern int ft_mach2;
+/*
+ *      fdc-io.c defined public functions
+ */
+extern void fdc_catch_stray_interrupts(int count);
+extern int fdc_ready_wait(unsigned int timeout);
+extern int fdc_command(const __u8 * cmd_data, int cmd_len);
+extern int fdc_result(__u8 * res_data, int res_len);
+extern int fdc_interrupt_wait(unsigned int time);
+extern int fdc_seek(int track);
+extern int fdc_sense_drive_status(int *st3);
+extern void fdc_motor(int motor);
+extern void fdc_reset(void);
+extern void fdc_disable(void);
+extern int fdc_fifo_threshold(__u8 threshold,
+			      int *fifo_state, int *lock_state, int *fifo_thr);
+extern void fdc_wait_calibrate(void);
+extern int fdc_sense_interrupt_status(int *st0, int *current_cylinder);
+extern void fdc_save_drive_specs(void);
+extern void fdc_restore_drive_specs(void);
+extern int fdc_set_data_rate(int rate);
+extern void fdc_set_write_precomp(int precomp);
+extern int fdc_release_irq_and_dma(void);
+extern void fdc_release_regions(void);
+extern int fdc_init(void);
+extern int fdc_setup_read_write(buffer_struct * buff, __u8 operation);
+extern int fdc_setup_formatting(buffer_struct * buff);
+#endif
diff --git a/drivers/char/ftape/lowlevel/fdc-isr.c b/drivers/char/ftape/lowlevel/fdc-isr.c
new file mode 100644
index 0000000..ad2bc73
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/fdc-isr.c
@@ -0,0 +1,1170 @@
+/*
+ *      Copyright (C) 1994-1996 Bas Laarhoven,
+ *                (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/fdc-isr.c,v $
+ * $Revision: 1.9 $
+ * $Date: 1997/10/17 23:01:53 $
+ *
+ *      This file contains the interrupt service routine and
+ *      associated code for the QIC-40/80/3010/3020 floppy-tape driver
+ *      "ftape" for Linux.
+ */
+
+#include <asm/io.h>
+#include <asm/dma.h>
+
+#define volatile		/* */
+
+#include <linux/ftape.h>
+#include <linux/qic117.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/fdc-isr.h"
+#include "../lowlevel/fdc-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-calibr.h"
+#include "../lowlevel/ftape-bsm.h"
+
+/*      Global vars.
+ */
+volatile int ft_expected_stray_interrupts;
+volatile int ft_interrupt_seen;
+volatile int ft_seek_completed;
+volatile int ft_hide_interrupt;
+/*      Local vars.
+ */
+typedef enum {
+	no_error = 0, id_am_error = 0x01, id_crc_error = 0x02,
+	data_am_error = 0x04, data_crc_error = 0x08,
+	no_data_error = 0x10, overrun_error = 0x20,
+} error_cause;
+static int stop_read_ahead;
+
+
+static void print_error_cause(int cause)
+{
+	TRACE_FUN(ft_t_any);
+
+	switch (cause) {
+	case no_data_error:
+		TRACE(ft_t_noise, "no data error");
+		break;
+	case id_am_error:
+		TRACE(ft_t_noise, "id am error");
+		break;
+	case id_crc_error:
+		TRACE(ft_t_noise, "id crc error");
+		break;
+	case data_am_error:
+		TRACE(ft_t_noise, "data am error");
+		break;
+	case data_crc_error:
+		TRACE(ft_t_noise, "data crc error");
+		break;
+	case overrun_error:
+		TRACE(ft_t_noise, "overrun error");
+		break;
+	default:;
+	}
+	TRACE_EXIT;
+}
+
+static char *fdc_mode_txt(fdc_mode_enum mode)
+{
+	switch (mode) {
+	case fdc_idle:
+		return "fdc_idle";
+	case fdc_reading_data:
+		return "fdc_reading_data";
+	case fdc_seeking:
+		return "fdc_seeking";
+	case fdc_writing_data:
+		return "fdc_writing_data";
+	case fdc_reading_id:
+		return "fdc_reading_id";
+	case fdc_recalibrating:
+		return "fdc_recalibrating";
+	case fdc_formatting:
+		return "fdc_formatting";
+	case fdc_verifying:
+		return "fdc_verifying";
+	default:
+		return "unknown";
+	}
+}
+
+static inline error_cause decode_irq_cause(fdc_mode_enum mode, __u8 st[])
+{
+	error_cause cause = no_error;
+	TRACE_FUN(ft_t_any);
+
+	/*  Valid st[], decode cause of interrupt.
+	 */
+	switch (st[0] & ST0_INT_MASK) {
+	case FDC_INT_NORMAL:
+		TRACE(ft_t_fdc_dma,"normal completion: %s",fdc_mode_txt(mode));
+		break;
+	case FDC_INT_ABNORMAL:
+		TRACE(ft_t_flow, "abnormal completion %s", fdc_mode_txt(mode));
+		TRACE(ft_t_fdc_dma, "ST0: 0x%02x, ST1: 0x%02x, ST2: 0x%02x",
+		      st[0], st[1], st[2]);
+		TRACE(ft_t_fdc_dma,
+		      "C: 0x%02x, H: 0x%02x, R: 0x%02x, N: 0x%02x",
+		      st[3], st[4], st[5], st[6]);
+		if (st[1] & 0x01) {
+			if (st[2] & 0x01) {
+				cause = data_am_error;
+			} else {
+				cause = id_am_error;
+			}
+		} else if (st[1] & 0x20) {
+			if (st[2] & 0x20) {
+				cause = data_crc_error;
+			} else {
+				cause = id_crc_error;
+			}
+		} else if (st[1] & 0x04) {
+			cause = no_data_error;
+		} else if (st[1] & 0x10) {
+			cause = overrun_error;
+		}
+		print_error_cause(cause);
+		break;
+	case FDC_INT_INVALID:
+		TRACE(ft_t_flow, "invalid completion %s", fdc_mode_txt(mode));
+		break;
+	case FDC_INT_READYCH:
+		if (st[0] & ST0_SEEK_END) {
+			TRACE(ft_t_flow, "drive poll completed");
+		} else {
+			TRACE(ft_t_flow, "ready change %s",fdc_mode_txt(mode));
+		}
+		break;
+	default:
+		break;
+	}
+	TRACE_EXIT cause;
+}
+
+static void update_history(error_cause cause)
+{
+	switch (cause) {
+	case id_am_error:
+		ft_history.id_am_errors++;
+		break;
+	case id_crc_error:
+		ft_history.id_crc_errors++;
+		break;
+	case data_am_error:
+		ft_history.data_am_errors++;
+		break;
+	case data_crc_error:
+		ft_history.data_crc_errors++;
+		break;
+	case overrun_error:
+		ft_history.overrun_errors++;
+		break;
+	case no_data_error:
+		ft_history.no_data_errors++;
+		break;
+	default:;
+	}
+}
+
+static void skip_bad_sector(buffer_struct * buff)
+{
+	TRACE_FUN(ft_t_any);
+
+	/*  Mark sector as soft error and skip it
+	 */
+	if (buff->remaining > 0) {
+		++buff->sector_offset;
+		++buff->data_offset;
+		--buff->remaining;
+		buff->ptr += FT_SECTOR_SIZE;
+		buff->bad_sector_map >>= 1;
+	} else {
+		/*  Hey, what is this????????????? C code: if we shift 
+		 *  more than 31 bits, we get no shift. That's bad!!!!!!
+		 */
+		++buff->sector_offset;	/* hack for error maps */
+		TRACE(ft_t_warn, "skipping last sector in segment");
+	}
+	TRACE_EXIT;
+}
+
+static void update_error_maps(buffer_struct * buff, unsigned int error_offset)
+{
+	int hard = 0;
+	TRACE_FUN(ft_t_any);
+
+	if (buff->retry < FT_SOFT_RETRIES) {
+		buff->soft_error_map |= (1 << error_offset);
+	} else {
+		buff->hard_error_map |= (1 << error_offset);
+		buff->soft_error_map &= ~buff->hard_error_map;
+		buff->retry = -1;  /* will be set to 0 in setup_segment */
+		hard = 1;
+	}
+	TRACE(ft_t_noise, "sector %d : %s error\n"
+	      KERN_INFO "hard map: 0x%08lx\n"
+	      KERN_INFO "soft map: 0x%08lx",
+	      FT_SECTOR(error_offset), hard ? "hard" : "soft",
+	      (long) buff->hard_error_map, (long) buff->soft_error_map);
+	TRACE_EXIT;
+}
+
+static void print_progress(buffer_struct *buff, error_cause cause)
+{
+	TRACE_FUN(ft_t_any);
+
+	switch (cause) {
+	case no_error: 
+		TRACE(ft_t_flow,"%d Sector(s) transferred", buff->sector_count);
+		break;
+	case no_data_error:
+		TRACE(ft_t_flow, "Sector %d not found",
+		      FT_SECTOR(buff->sector_offset));
+		break;
+	case overrun_error:
+		/*  got an overrun error on the first byte, must be a
+		 *  hardware problem
+		 */
+		TRACE(ft_t_bug,
+		      "Unexpected error: failing DMA or FDC controller ?");
+		break;
+	case data_crc_error:
+		TRACE(ft_t_flow, "Error in sector %d",
+		      FT_SECTOR(buff->sector_offset - 1));
+		break;
+	case id_crc_error:
+	case id_am_error:
+	case data_am_error:
+		TRACE(ft_t_flow, "Error in sector %d",
+		      FT_SECTOR(buff->sector_offset));
+		break;
+	default:
+		TRACE(ft_t_flow, "Unexpected error at sector %d",
+		      FT_SECTOR(buff->sector_offset));
+		break;
+	}
+	TRACE_EXIT;
+}
+
+/*
+ *  Error cause:   Amount xferred:  Action:
+ *
+ *  id_am_error         0           mark bad and skip
+ *  id_crc_error        0           mark bad and skip
+ *  data_am_error       0           mark bad and skip
+ *  data_crc_error    % 1024        mark bad and skip
+ *  no_data_error       0           retry on write
+ *                                  mark bad and skip on read
+ *  overrun_error  [ 0..all-1 ]     mark bad and skip
+ *  no_error           all          continue
+ */
+
+/*  the arg `sector' is returned by the fdc and tells us at which sector we
+ *  are positioned at (relative to starting sector of segment)
+ */
+static void determine_verify_progress(buffer_struct *buff,
+				      error_cause cause,
+				      __u8 sector)
+{
+	TRACE_FUN(ft_t_any);
+
+	if (cause == no_error && sector == 1) {
+		buff->sector_offset = FT_SECTORS_PER_SEGMENT;
+		buff->remaining     = 0;
+		if (TRACE_LEVEL >= ft_t_flow) {
+			print_progress(buff, cause);
+		}
+	} else {
+		buff->sector_offset = sector - buff->sect;
+		buff->remaining = FT_SECTORS_PER_SEGMENT - buff->sector_offset;
+		TRACE(ft_t_noise, "%ssector offset: 0x%04x", 
+		      (cause == no_error) ? "unexpected " : "",
+		      buff->sector_offset);
+		switch (cause) {
+		case overrun_error:
+			break;
+#if 0
+		case no_data_error:
+			buff->retry = FT_SOFT_RETRIES;
+			if (buff->hard_error_map    &&
+			    buff->sector_offset > 1 &&
+			    (buff->hard_error_map & 
+			     (1 << (buff->sector_offset-2)))) {
+				buff->retry --;
+			}
+			break;
+#endif
+		default:
+			buff->retry = FT_SOFT_RETRIES;
+			break;
+		}
+		if (TRACE_LEVEL >= ft_t_flow) {
+			print_progress(buff, cause);
+		}
+		/*  Sector_offset points to the problem area Now adjust
+		 *  sector_offset so it always points one past he failing
+		 *  sector. I.e. skip the bad sector.
+		 */
+		++buff->sector_offset;
+		--buff->remaining;
+		update_error_maps(buff, buff->sector_offset - 1);
+	}
+	TRACE_EXIT;
+}
+
+static void determine_progress(buffer_struct *buff,
+			       error_cause cause,
+			       __u8 sector)
+{
+	unsigned int dma_residue;
+	TRACE_FUN(ft_t_any);
+
+	/*  Using less preferred order of disable_dma and
+	 *  get_dma_residue because this seems to fail on at least one
+	 *  system if reversed!
+	 */
+	dma_residue = get_dma_residue(fdc.dma);
+	disable_dma(fdc.dma);
+	if (cause != no_error || dma_residue != 0) {
+		TRACE(ft_t_noise, "%sDMA residue: 0x%04x", 
+		      (cause == no_error) ? "unexpected " : "",
+		      dma_residue);
+		/* adjust to actual value: */
+		if (dma_residue == 0) {
+			/* this happens sometimes with overrun errors.
+			 * I don't know whether we could ignore the
+			 * overrun error. Play save.
+			 */
+			buff->sector_count --;
+		} else {
+			buff->sector_count -= ((dma_residue + 
+						(FT_SECTOR_SIZE - 1)) /
+					       FT_SECTOR_SIZE);
+		}
+	}
+	/*  Update var's influenced by the DMA operation.
+	 */
+	if (buff->sector_count > 0) {
+		buff->sector_offset   += buff->sector_count;
+		buff->data_offset     += buff->sector_count;
+		buff->ptr             += (buff->sector_count *
+					  FT_SECTOR_SIZE);
+		buff->remaining       -= buff->sector_count;
+		buff->bad_sector_map >>= buff->sector_count;
+	}
+	if (TRACE_LEVEL >= ft_t_flow) {
+		print_progress(buff, cause);
+	}
+	if (cause != no_error) {
+		if (buff->remaining == 0) {
+			TRACE(ft_t_warn, "foo?\n"
+			      KERN_INFO "count : %d\n"
+			      KERN_INFO "offset: %d\n"
+			      KERN_INFO "soft  : %08x\n"
+			      KERN_INFO "hard  : %08x",
+			      buff->sector_count,
+			      buff->sector_offset,
+			      buff->soft_error_map,
+			      buff->hard_error_map);
+		}
+		/*  Sector_offset points to the problem area, except if we got
+		 *  a data_crc_error. In that case it points one past the
+		 *  failing sector.
+		 *
+		 *  Now adjust sector_offset so it always points one past he
+		 *  failing sector. I.e. skip the bad sector.  
+		 */
+		if (cause != data_crc_error) {
+			skip_bad_sector(buff);
+		}
+		update_error_maps(buff, buff->sector_offset - 1);
+	}
+	TRACE_EXIT;
+}
+
+static int calc_steps(int cmd)
+{
+	if (ftape_current_cylinder > cmd) {
+		return ftape_current_cylinder - cmd;
+	} else {
+		return ftape_current_cylinder + cmd;
+	}
+}
+
+static void pause_tape(int retry, int mode)
+{
+	int result;
+	__u8 out[3] = {FDC_SEEK, ft_drive_sel, 0};
+	TRACE_FUN(ft_t_any);
+
+	/*  We'll use a raw seek command to get the tape to rewind and
+	 *  stop for a retry.
+	 */
+	++ft_history.rewinds;
+	if (qic117_cmds[ftape_current_command].non_intr) {
+		TRACE(ft_t_warn, "motion command may be issued too soon");
+	}
+	if (retry && (mode == fdc_reading_data ||
+		      mode == fdc_reading_id   ||
+		      mode == fdc_verifying)) {
+		ftape_current_command = QIC_MICRO_STEP_PAUSE;
+		ftape_might_be_off_track = 1;
+	} else {
+		ftape_current_command = QIC_PAUSE;
+	}
+	out[2] = calc_steps(ftape_current_command);
+	result = fdc_command(out, 3); /* issue QIC_117 command */
+	ftape_current_cylinder = out[ 2];
+	if (result < 0) {
+		TRACE(ft_t_noise, "qic-pause failed, status = %d", result);
+	} else {
+		ft_location.known  = 0;
+		ft_runner_status   = idle;
+		ft_hide_interrupt     = 1;
+		ftape_tape_running = 0;
+	}
+	TRACE_EXIT;
+}
+
+static void continue_xfer(buffer_struct *buff,
+			  fdc_mode_enum mode, 
+			  unsigned int skip)
+{
+	int write = 0;
+ 	TRACE_FUN(ft_t_any);
+
+	if (mode == fdc_writing_data || mode == fdc_deleting) {
+		write = 1;
+	}
+	/*  This part can be removed if it never happens
+	 */
+	if (skip > 0 &&
+	    (ft_runner_status != running ||
+	     (write && (buff->status != writing)) ||
+	     (!write && (buff->status != reading && 
+			 buff->status != verifying)))) {
+		TRACE(ft_t_err, "unexpected runner/buffer state %d/%d",
+		      ft_runner_status, buff->status);
+		buff->status = error;
+		/* finish this buffer: */
+		(void)ftape_next_buffer(ft_queue_head);
+		ft_runner_status = aborting;
+		fdc_mode         = fdc_idle;
+	} else if (buff->remaining > 0 && ftape_calc_next_cluster(buff) > 0) {
+		/*  still sectors left in current segment, continue
+		 *  with this segment
+		 */
+		if (fdc_setup_read_write(buff, mode) < 0) {
+			/* failed, abort operation
+			 */
+			buff->bytes = buff->ptr - buff->address;
+			buff->status = error;
+			/* finish this buffer: */
+			(void)ftape_next_buffer(ft_queue_head);
+			ft_runner_status = aborting;
+			fdc_mode         = fdc_idle;
+		}
+	} else {
+		/* current segment completed
+		 */
+		unsigned int last_segment = buff->segment_id;
+		int eot = ((last_segment + 1) % ft_segments_per_track) == 0;
+		unsigned int next = buff->next_segment;	/* 0 means stop ! */
+
+		buff->bytes = buff->ptr - buff->address;
+		buff->status = done;
+		buff = ftape_next_buffer(ft_queue_head);
+		if (eot) {
+			/*  finished last segment on current track,
+			 *  can't continue
+			 */
+			ft_runner_status = logical_eot;
+			fdc_mode         = fdc_idle;
+			TRACE_EXIT;
+		}
+		if (next <= 0) {
+			/*  don't continue with next segment
+			 */
+			TRACE(ft_t_noise, "no %s allowed, stopping tape",
+			      (write) ? "write next" : "read ahead");
+			pause_tape(0, mode);
+			ft_runner_status = idle;  /*  not quite true until
+						   *  next irq 
+						   */
+			TRACE_EXIT;
+		}
+		/*  continue with next segment
+		 */
+		if (buff->status != waiting) {
+			TRACE(ft_t_noise, "all input buffers %s, pausing tape",
+			      (write) ? "empty" : "full");
+			pause_tape(0, mode);
+			ft_runner_status = idle;  /*  not quite true until
+						   *  next irq 
+						   */
+			TRACE_EXIT;
+		}
+		if (write && next != buff->segment_id) {
+			TRACE(ft_t_noise, 
+			      "segments out of order, aborting write");
+			ft_runner_status = do_abort;
+			fdc_mode         = fdc_idle;
+			TRACE_EXIT;
+		}
+		ftape_setup_new_segment(buff, next, 0);
+		if (stop_read_ahead) {
+			buff->next_segment = 0;
+			stop_read_ahead = 0;
+		}
+		if (ftape_calc_next_cluster(buff) == 0 ||
+		    fdc_setup_read_write(buff, mode) != 0) {
+			TRACE(ft_t_err, "couldn't start %s-ahead",
+			      write ? "write" : "read");
+			ft_runner_status = do_abort;
+			fdc_mode         = fdc_idle;
+		} else {
+			/* keep on going */
+			switch (ft_driver_state) {
+			case   reading: buff->status = reading;   break;
+			case verifying: buff->status = verifying; break;
+			case   writing: buff->status = writing;   break;
+			case  deleting: buff->status = deleting;  break;
+			default:
+				TRACE(ft_t_err, 
+		      "BUG: ft_driver_state %d should be one out of "
+		      "{reading, writing, verifying, deleting}",
+				      ft_driver_state);
+				buff->status = write ? writing : reading;
+				break;
+			}
+		}
+	}
+	TRACE_EXIT;
+}
+
+static void retry_sector(buffer_struct *buff, 
+			 int mode,
+			 unsigned int skip)
+{
+	TRACE_FUN(ft_t_any);
+
+	TRACE(ft_t_noise, "%s error, will retry",
+	      (mode == fdc_writing_data || mode == fdc_deleting) ? "write" : "read");
+	pause_tape(1, mode);
+	ft_runner_status = aborting;
+	buff->status     = error;
+	buff->skip       = skip;
+	TRACE_EXIT;
+}
+
+static unsigned int find_resume_point(buffer_struct *buff)
+{
+	int i = 0;
+	SectorMap mask;
+	SectorMap map;
+	TRACE_FUN(ft_t_any);
+
+	/*  This function is to be called after all variables have been
+	 *  updated to point past the failing sector.
+	 *  If there are any soft errors before the failing sector,
+	 *  find the first soft error and return the sector offset.
+	 *  Otherwise find the last hard error.
+	 *  Note: there should always be at least one hard or soft error !
+	 */
+	if (buff->sector_offset < 1 || buff->sector_offset > 32) {
+		TRACE(ft_t_bug, "BUG: sector_offset = %d",
+		      buff->sector_offset);
+		TRACE_EXIT 0;
+	}
+	if (buff->sector_offset >= 32) { /* C-limitation on shift ! */
+		mask = 0xffffffff;
+	} else {
+		mask = (1 << buff->sector_offset) - 1;
+	}
+	map = buff->soft_error_map & mask;
+	if (map) {
+		while ((map & (1 << i)) == 0) {
+			++i;
+		}
+		TRACE(ft_t_noise, "at sector %d", FT_SECTOR(i));
+	} else {
+		map = buff->hard_error_map & mask;
+		i = buff->sector_offset - 1;
+		if (map) {
+			while ((map & (1 << i)) == 0) {
+				--i;
+			}
+			TRACE(ft_t_noise, "after sector %d", FT_SECTOR(i));
+			++i; /* first sector after last hard error */
+		} else {
+			TRACE(ft_t_bug, "BUG: no soft or hard errors");
+		}
+	}
+	TRACE_EXIT i;
+}
+
+/*  check possible dma residue when formatting, update position record in
+ *  buffer struct. This is, of course, modelled after determine_progress(), but
+ *  we don't need to set up for retries because the format process cannot be
+ *  interrupted (except at the end of the tape track).
+ */
+static int determine_fmt_progress(buffer_struct *buff, error_cause cause)
+{
+	unsigned int dma_residue;
+	TRACE_FUN(ft_t_any);
+
+	/*  Using less preferred order of disable_dma and
+	 *  get_dma_residue because this seems to fail on at least one
+	 *  system if reversed!
+	 */
+	dma_residue = get_dma_residue(fdc.dma);
+	disable_dma(fdc.dma);
+	if (cause != no_error || dma_residue != 0) {
+		TRACE(ft_t_info, "DMA residue = 0x%04x", dma_residue);
+		fdc_mode = fdc_idle;
+		switch(cause) {
+		case no_error:
+			ft_runner_status = aborting;
+			buff->status = idle;
+			break;
+		case overrun_error:
+			/*  got an overrun error on the first byte, must be a
+			 *  hardware problem 
+			 */
+			TRACE(ft_t_bug, 
+			      "Unexpected error: failing DMA controller ?");
+			ft_runner_status = do_abort;
+			buff->status = error;
+			break;
+		default:
+			TRACE(ft_t_noise, "Unexpected error at segment %d",
+			      buff->segment_id);
+			ft_runner_status = do_abort;
+			buff->status = error;
+			break;
+		}
+		TRACE_EXIT -EIO; /* can only retry entire track in format mode
+				  */
+	}
+	/*  Update var's influenced by the DMA operation.
+	 */
+	buff->ptr             += FT_SECTORS_PER_SEGMENT * 4;
+	buff->bytes           -= FT_SECTORS_PER_SEGMENT * 4;
+	buff->remaining       -= FT_SECTORS_PER_SEGMENT;
+	buff->segment_id ++; /* done with segment */
+	TRACE_EXIT 0;
+}
+
+/*
+ *  Continue formatting, switch buffers if there is no data left in
+ *  current buffer. This is, of course, modelled after
+ *  continue_xfer(), but we don't need to set up for retries because
+ *  the format process cannot be interrupted (except at the end of the
+ *  tape track).
+ */
+static void continue_formatting(buffer_struct *buff)
+{
+	TRACE_FUN(ft_t_any);
+
+	if (buff->remaining <= 0) { /*  no space left in dma buffer */
+		unsigned int next = buff->next_segment; 
+
+		if (next == 0) { /* end of tape track */
+			buff->status     = done;
+			ft_runner_status = logical_eot;
+			fdc_mode         = fdc_idle;
+			TRACE(ft_t_noise, "Done formatting track %d",
+			      ft_location.track);
+			TRACE_EXIT;
+		}
+		/*
+		 *  switch to next buffer!
+		 */
+		buff->status   = done;
+		buff = ftape_next_buffer(ft_queue_head);
+
+		if (buff->status != waiting  || next != buff->segment_id) {
+			goto format_setup_error;
+		}
+	}
+	if (fdc_setup_formatting(buff) < 0) {
+		goto format_setup_error;
+	}
+	buff->status = formatting;
+	TRACE(ft_t_fdc_dma, "Formatting segment %d on track %d",
+	      buff->segment_id, ft_location.track);
+	TRACE_EXIT;
+ format_setup_error:
+	ft_runner_status = do_abort;
+	fdc_mode         = fdc_idle;
+	buff->status     = error;
+	TRACE(ft_t_err, "Error setting up for segment %d on track %d",
+	      buff->segment_id, ft_location.track);
+	TRACE_EXIT;
+
+}
+
+/*  this handles writing, read id, reading and formatting
+ */
+static void handle_fdc_busy(buffer_struct *buff)
+{
+	static int no_data_error_count;
+	int retry = 0;
+	error_cause cause;
+	__u8 in[7];
+	int skip;
+	fdc_mode_enum fmode = fdc_mode;
+	TRACE_FUN(ft_t_any);
+
+	if (fdc_result(in, 7) < 0) { /* better get it fast ! */
+		TRACE(ft_t_err, 
+		      "Probably fatal error during FDC Result Phase\n"
+		      KERN_INFO
+		      "drive may hang until (power on) reset :-(");
+		/*  what to do next ????
+		 */
+		TRACE_EXIT;
+	}
+	cause = decode_irq_cause(fdc_mode, in);
+#ifdef TESTING
+	{ int i;
+	for (i = 0; i < (int)ft_nr_buffers; ++i)
+		TRACE(ft_t_any, "buffer[%d] status: %d, segment_id: %d",
+		      i, ft_buffer[i]->status, ft_buffer[i]->segment_id);
+	}
+#endif
+	if (fmode == fdc_reading_data && ft_driver_state == verifying) {
+		fmode = fdc_verifying;
+	}
+	switch (fmode) {
+	case fdc_verifying:
+		if (ft_runner_status == aborting ||
+		    ft_runner_status == do_abort) {
+			TRACE(ft_t_noise,"aborting %s",fdc_mode_txt(fdc_mode));
+			break;
+		}
+		if (buff->retry > 0) {
+			TRACE(ft_t_flow, "this is retry nr %d", buff->retry);
+		}
+		switch (cause) {
+		case no_error:
+			no_data_error_count = 0;
+			determine_verify_progress(buff, cause, in[5]);
+			if (in[2] & 0x40) {
+				/*  This should not happen when verifying
+				 */
+				TRACE(ft_t_warn,
+				      "deleted data in segment %d/%d",
+				      buff->segment_id,
+				      FT_SECTOR(buff->sector_offset - 1));
+				buff->remaining = 0; /* abort transfer */
+				buff->hard_error_map = EMPTY_SEGMENT;
+				skip = 1;
+			} else {
+				skip = 0;
+			}
+			continue_xfer(buff, fdc_mode, skip);
+			break;
+		case no_data_error:
+			no_data_error_count ++;
+		case overrun_error:
+			retry ++;
+		case id_am_error:
+		case id_crc_error:
+		case data_am_error:
+		case data_crc_error:
+			determine_verify_progress(buff, cause, in[5]); 
+			if (cause == no_data_error) {
+				if (no_data_error_count >= 2) {
+					TRACE(ft_t_warn,
+					      "retrying because of successive "
+					      "no data errors");
+					no_data_error_count = 0;
+				} else {
+					retry --;
+				}
+			} else {
+				no_data_error_count = 0;
+			}
+			if (retry) {
+				skip = find_resume_point(buff);
+			} else {
+				skip = buff->sector_offset;
+			}
+			if (retry && skip < 32) {
+				retry_sector(buff, fdc_mode, skip);
+			} else {
+				continue_xfer(buff, fdc_mode, skip);
+			}
+			update_history(cause);
+			break;
+		default:
+			/*  Don't know why this could happen 
+			 *  but find out.
+			 */
+			determine_verify_progress(buff, cause, in[5]);
+			retry_sector(buff, fdc_mode, 0);
+			TRACE(ft_t_err, "Error: unexpected error");
+			break;
+		}
+		break;
+	case fdc_reading_data:
+#ifdef TESTING
+		/* I'm sorry, but: NOBODY ever used this trace
+		 * messages for ages. I guess that Bas was the last person
+		 * that ever really used this (thank you, between the lines)
+		 */
+		if (cause == no_error) {
+			TRACE(ft_t_flow,"reading segment %d",buff->segment_id);
+		} else {
+			TRACE(ft_t_noise, "error reading segment %d",
+			      buff->segment_id);
+			TRACE(ft_t_noise, "\n"
+			      KERN_INFO
+			     "IRQ:C: 0x%02x, H: 0x%02x, R: 0x%02x, N: 0x%02x\n"
+			      KERN_INFO
+			      "BUF:C: 0x%02x, H: 0x%02x, R: 0x%02x",
+			      in[3], in[4], in[5], in[6],
+			      buff->cyl, buff->head, buff->sect);
+		}
+#endif
+		if (ft_runner_status == aborting ||
+		    ft_runner_status == do_abort) {
+			TRACE(ft_t_noise,"aborting %s",fdc_mode_txt(fdc_mode));
+			break;
+		}
+		if (buff->bad_sector_map == FAKE_SEGMENT) {
+			/* This condition occurs when reading a `fake'
+			 * sector that's not accessible. Doesn't
+			 * really matter as we would have ignored it
+			 * anyway !
+			 *
+			 * Chance is that we're past the next segment
+			 * now, so the next operation may fail and
+			 * result in a retry.  
+			 */
+			buff->remaining = 0;	/* skip failing sector */
+			/* buff->ptr       = buff->address; */
+			/* fake success: */
+			continue_xfer(buff, fdc_mode, 1);
+			/*  trace calls are expensive: place them AFTER
+			 *  the real stuff has been done.
+			 *  
+			 */
+			TRACE(ft_t_noise, "skipping empty segment %d (read), size? %d",
+			      buff->segment_id, buff->ptr - buff->address);
+			TRACE_EXIT;
+		}
+		if (buff->retry > 0) {
+			TRACE(ft_t_flow, "this is retry nr %d", buff->retry);
+		}
+		switch (cause) {
+		case no_error:
+			determine_progress(buff, cause, in[5]);
+			if (in[2] & 0x40) {
+				/*  Handle deleted data in header segments.
+				 *  Skip segment and force read-ahead.
+				 */
+				TRACE(ft_t_warn,
+				      "deleted data in segment %d/%d",
+				      buff->segment_id,
+				      FT_SECTOR(buff->sector_offset - 1));
+				buff->deleted = 1;
+				buff->remaining = 0;/*abort transfer */
+				buff->soft_error_map |=
+						(-1L << buff->sector_offset);
+				if (buff->segment_id == 0) {
+					/* stop on next segment */
+					stop_read_ahead = 1;
+				}
+				/* force read-ahead: */
+				buff->next_segment = 
+					buff->segment_id + 1;
+				skip = (FT_SECTORS_PER_SEGMENT - 
+					buff->sector_offset);
+			} else {
+				skip = 0;
+			}
+			continue_xfer(buff, fdc_mode, skip);
+			break;
+		case no_data_error:
+			/* Tape started too far ahead of or behind the
+			 * right sector.  This may also happen in the
+			 * middle of a segment !
+			 *
+			 * Handle no-data as soft error. If next
+			 * sector fails too, a retry (with needed
+			 * reposition) will follow.
+			 */
+			retry ++;
+		case id_am_error:
+		case id_crc_error:
+		case data_am_error:
+		case data_crc_error:
+		case overrun_error:
+			retry += (buff->soft_error_map != 0 ||
+				  buff->hard_error_map != 0);
+			determine_progress(buff, cause, in[5]); 
+#if 1 || defined(TESTING)
+			if (cause == overrun_error) retry ++;
+#endif
+			if (retry) {
+				skip = find_resume_point(buff);
+			} else {
+				skip = buff->sector_offset;
+			}
+			/*  Try to resume with next sector on single
+			 *  errors (let ecc correct it), but retry on
+			 *  no_data (we'll be past the target when we
+			 *  get here so we cannot retry) or on
+			 *  multiple errors (reduce chance on ecc
+			 *  failure).
+			 */
+			/*  cH: 23/02/97: if the last sector in the 
+			 *  segment was a hard error, then there is 
+			 *  no sense in a retry. This occasion seldom
+			 *  occurs but ... @:³²¸`@%&§$
+			 */
+			if (retry && skip < 32) {
+				retry_sector(buff, fdc_mode, skip);
+			} else {
+				continue_xfer(buff, fdc_mode, skip);
+			}
+			update_history(cause);
+			break;
+		default:
+			/*  Don't know why this could happen 
+			 *  but find out.
+			 */
+			determine_progress(buff, cause, in[5]);
+			retry_sector(buff, fdc_mode, 0);
+			TRACE(ft_t_err, "Error: unexpected error");
+			break;
+		}
+		break;
+	case fdc_reading_id:
+		if (cause == no_error) {
+			fdc_cyl = in[3];
+			fdc_head = in[4];
+			fdc_sect = in[5];
+			TRACE(ft_t_fdc_dma,
+			      "id read: C: 0x%02x, H: 0x%02x, R: 0x%02x",
+			      fdc_cyl, fdc_head, fdc_sect);
+		} else {	/* no valid information, use invalid sector */
+			fdc_cyl = fdc_head = fdc_sect = 0;
+			TRACE(ft_t_flow, "Didn't find valid sector Id");
+		}
+		fdc_mode = fdc_idle;
+		break;
+	case fdc_deleting:
+	case fdc_writing_data:
+#ifdef TESTING
+		if (cause == no_error) {
+			TRACE(ft_t_flow, "writing segment %d", buff->segment_id);
+		} else {
+			TRACE(ft_t_noise, "error writing segment %d",
+			      buff->segment_id);
+		}
+#endif
+		if (ft_runner_status == aborting ||
+		    ft_runner_status == do_abort) {
+			TRACE(ft_t_flow, "aborting %s",fdc_mode_txt(fdc_mode));
+			break;
+		}
+		if (buff->retry > 0) {
+			TRACE(ft_t_flow, "this is retry nr %d", buff->retry);
+		}
+		if (buff->bad_sector_map == FAKE_SEGMENT) {
+			/* This condition occurs when trying to write to a
+			 * `fake' sector that's not accessible. Doesn't really
+			 * matter as it isn't used anyway ! Might be located
+			 * at wrong segment, then we'll fail on the next
+			 * segment.
+			 */
+			TRACE(ft_t_noise, "skipping empty segment (write)");
+			buff->remaining = 0;	/* skip failing sector */
+			/* fake success: */
+			continue_xfer(buff, fdc_mode, 1);
+			break;
+		}
+		switch (cause) {
+		case no_error:
+			determine_progress(buff, cause, in[5]);
+			continue_xfer(buff, fdc_mode, 0);
+			break;
+		case no_data_error:
+		case id_am_error:
+		case id_crc_error:
+		case data_am_error:
+		case overrun_error:
+			update_history(cause);
+			determine_progress(buff, cause, in[5]);
+			skip = find_resume_point(buff);
+			retry_sector(buff, fdc_mode, skip);
+			break;
+		default:
+			if (in[1] & 0x02) {
+				TRACE(ft_t_err, "media not writable");
+			} else {
+				TRACE(ft_t_bug, "unforeseen write error");
+			}
+			fdc_mode = fdc_idle;
+			break;
+		}
+		break; /* fdc_deleting || fdc_writing_data */
+	case fdc_formatting:
+		/*  The interrupt comes after formatting a segment. We then
+		 *  have to set up QUICKLY for the next segment. But
+		 *  afterwards, there is plenty of time.
+		 */
+		switch (cause) {
+		case no_error:
+			/*  would like to keep most of the formatting stuff
+			 *  outside the isr code, but timing is too critical
+			 */
+			if (determine_fmt_progress(buff, cause) >= 0) {
+				continue_formatting(buff);
+			}
+			break;
+		case no_data_error:
+		case id_am_error:
+		case id_crc_error:
+		case data_am_error:
+		case overrun_error:
+		default:
+			determine_fmt_progress(buff, cause);
+			update_history(cause);
+			if (in[1] & 0x02) {
+				TRACE(ft_t_err, "media not writable");
+			} else {
+				TRACE(ft_t_bug, "unforeseen write error");
+			}
+			break;
+		} /* cause */
+		break;
+	default:
+		TRACE(ft_t_warn, "Warning: unexpected irq during: %s",
+		      fdc_mode_txt(fdc_mode));
+		fdc_mode = fdc_idle;
+		break;
+	}
+	TRACE_EXIT;
+}
+
+/*      FDC interrupt service routine.
+ */
+void fdc_isr(void)
+{
+	static int isr_active;
+#ifdef TESTING
+	unsigned int t0 = ftape_timestamp();
+#endif
+	TRACE_FUN(ft_t_any);
+
+ 	if (isr_active++) {
+		--isr_active;
+		TRACE(ft_t_bug, "BUG: nested interrupt, not good !");
+		*fdc.hook = fdc_isr; /*  hook our handler into the fdc
+				      *  code again 
+				      */
+		TRACE_EXIT;
+	}
+	sti();
+	if (inb_p(fdc.msr) & FDC_BUSY) {	/*  Entering Result Phase */
+		ft_hide_interrupt = 0;
+		handle_fdc_busy(ftape_get_buffer(ft_queue_head));
+		if (ft_runner_status == do_abort) {
+			/*      cease operation, remember tape position
+			 */
+			TRACE(ft_t_flow, "runner aborting");
+			ft_runner_status = aborting;
+			++ft_expected_stray_interrupts;
+		}
+	} else { /* !FDC_BUSY */
+		/*  clear interrupt, cause should be gotten by issuing
+		 *  a Sense Interrupt Status command.
+		 */
+		if (fdc_mode == fdc_recalibrating || fdc_mode == fdc_seeking) {
+			if (ft_hide_interrupt) {
+				int st0;
+				int pcn;
+
+				if (fdc_sense_interrupt_status(&st0, &pcn) < 0)
+					TRACE(ft_t_err,
+					      "sense interrupt status failed");
+				ftape_current_cylinder = pcn;
+				TRACE(ft_t_flow, "handled hidden interrupt");
+			}
+			ft_seek_completed = 1;
+			fdc_mode = fdc_idle;
+		} else if (!waitqueue_active(&ftape_wait_intr)) {
+			if (ft_expected_stray_interrupts == 0) {
+				TRACE(ft_t_warn, "unexpected stray interrupt");
+			} else {
+				TRACE(ft_t_flow, "expected stray interrupt");
+				--ft_expected_stray_interrupts;
+			}
+		} else {
+			if (fdc_mode == fdc_reading_data ||
+			    fdc_mode == fdc_verifying    ||
+			    fdc_mode == fdc_writing_data ||
+			    fdc_mode == fdc_deleting     ||
+			    fdc_mode == fdc_formatting   ||
+			    fdc_mode == fdc_reading_id) {
+				if (inb_p(fdc.msr) & FDC_BUSY) {
+					TRACE(ft_t_bug,
+					"***** FDC failure, busy too late");
+				} else {
+					TRACE(ft_t_bug,
+					      "***** FDC failure, no busy");
+				}
+			} else {
+				TRACE(ft_t_fdc_dma, "awaited stray interrupt");
+			}
+		}
+		ft_hide_interrupt = 0;
+	}
+	/*    Handle sleep code.
+	 */
+	if (!ft_hide_interrupt) {
+		ft_interrupt_seen ++;
+		if (waitqueue_active(&ftape_wait_intr)) {
+			wake_up_interruptible(&ftape_wait_intr);
+		}
+	} else {
+		TRACE(ft_t_flow, "hiding interrupt while %s", 
+		      waitqueue_active(&ftape_wait_intr) ? "waiting":"active");
+	}
+#ifdef TESTING
+	t0 = ftape_timediff(t0, ftape_timestamp());
+	if (t0 >= 1000) {
+		/* only tell us about long calls */
+		TRACE(ft_t_noise, "isr() duration: %5d usec", t0);
+	}
+#endif
+	*fdc.hook = fdc_isr;	/* hook our handler into the fdc code again */
+	--isr_active;
+	TRACE_EXIT;
+}
diff --git a/drivers/char/ftape/lowlevel/fdc-isr.h b/drivers/char/ftape/lowlevel/fdc-isr.h
new file mode 100644
index 0000000..065aa97
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/fdc-isr.h
@@ -0,0 +1,55 @@
+#ifndef _FDC_ISR_H
+#define _FDC_ISR_H
+
+/*
+ * Copyright (C) 1993-1996 Bas Laarhoven,
+ *           (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/fdc-isr.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:07 $
+ *
+ *      This file declares the global variables necessary to
+ *      synchronize the interrupt service routine (isr) with the
+ *      remainder of the QIC-40/80/3010/3020 floppy-tape driver
+ *      "ftape" for Linux.
+ */
+
+/*
+ *      fdc-isr.c defined public variables
+ */
+extern volatile int ft_expected_stray_interrupts; /* masks stray interrupts */
+extern volatile int ft_seek_completed;	          /* flag set by isr */
+extern volatile int ft_interrupt_seen;	          /* flag set by isr */
+extern volatile int ft_hide_interrupt;            /* flag set by isr */
+
+/*
+ *      fdc-io.c defined public functions
+ */
+extern void fdc_isr(void);
+
+/*
+ *      A kernel hook that steals one interrupt from the floppy
+ *      driver (Should be fixed when the new fdc driver gets ready)
+ *      See the linux kernel source files:
+ *          drivers/block/floppy.c & drivers/block/blk.h
+ *      for the details.
+ */
+extern void (*do_floppy) (void);
+
+#endif
diff --git a/drivers/char/ftape/lowlevel/ftape-bsm.c b/drivers/char/ftape/lowlevel/ftape-bsm.c
new file mode 100644
index 0000000..d1a301c
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-bsm.c
@@ -0,0 +1,491 @@
+/*
+ *      Copyright (C) 1994-1996 Bas Laarhoven,
+ *                (C) 1996-1997 Claus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-bsm.c,v $
+ * $Revision: 1.3 $
+ * $Date: 1997/10/05 19:15:15 $
+ *
+ *      This file contains the bad-sector map handling code for
+ *      the QIC-117 floppy tape driver for Linux.
+ *      QIC-40, QIC-80, QIC-3010 and QIC-3020 maps are implemented.
+ */
+
+#include <linux/string.h>
+
+#include <linux/ftape.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-bsm.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+
+/*      Global vars.
+ */
+
+/*      Local vars.
+ */
+static __u8 *bad_sector_map;
+static SectorCount *bsm_hash_ptr; 
+
+typedef enum {
+	forward, backward
+} mode_type;
+
+#if 0
+static void ftape_put_bad_sector_entry(int segment_id, SectorMap new_map);
+#endif
+
+#if 0
+/*  fix_tape converts a normal QIC-80 tape into a 'wide' tape.
+ *  For testing purposes only !
+ */
+void fix_tape(__u8 * buffer, ft_format_type new_code)
+{
+	static __u8 list[BAD_SECTOR_MAP_SIZE];
+	SectorMap *src_ptr = (SectorMap *) list;
+	__u8 *dst_ptr = bad_sector_map;
+	SectorMap map;
+	unsigned int sector = 1;
+	int i;
+
+	if (format_code != fmt_var && format_code != fmt_big) {
+		memcpy(list, bad_sector_map, sizeof(list));
+		memset(bad_sector_map, 0, sizeof(bad_sector_map));
+		while ((__u8 *) src_ptr - list < sizeof(list)) {
+			map = *src_ptr++;
+			if (map == EMPTY_SEGMENT) {
+				*(SectorMap *) dst_ptr = 0x800000 + sector;
+				dst_ptr += 3;
+				sector += SECTORS_PER_SEGMENT;
+			} else {
+				for (i = 0; i < SECTORS_PER_SEGMENT; ++i) {
+					if (map & 1) {
+						*(SewctorMap *) dst_ptr = sector;
+						dst_ptr += 3;
+					}
+					map >>= 1;
+					++sector;
+				}
+			}
+		}
+	}
+	bad_sector_map_changed = 1;
+	*(buffer + 4) = new_code;	/* put new format code */
+	if (format_code != fmt_var && new_code == fmt_big) {
+		PUT4(buffer, FT_6_HSEG_1,   (__u32)GET2(buffer, 6));
+		PUT4(buffer, FT_6_HSEG_2,   (__u32)GET2(buffer, 8));
+		PUT4(buffer, FT_6_FRST_SEG, (__u32)GET2(buffer, 10));
+		PUT4(buffer, FT_6_LAST_SEG, (__u32)GET2(buffer, 12));
+		memset(buffer+6, '\0', 8);
+	}
+	format_code = new_code;
+}
+
+#endif
+
+/*   given buffer that contains a header segment, find the end of
+ *   of the bsm list
+ */
+__u8 * ftape_find_end_of_bsm_list(__u8 * address)
+{
+	__u8 *ptr   = address + FT_HEADER_END; /* start of bsm list */
+	__u8 *limit = address + FT_SEGMENT_SIZE;
+	while (ptr + 2 < limit) {
+		if (ptr[0] || ptr[1] || ptr[2]) {
+			ptr += 3;
+		} else {
+			return ptr;
+		}
+	}
+	return NULL;
+}
+
+static inline void put_sector(SectorCount *ptr, unsigned int sector)
+{
+	ptr->bytes[0] = sector & 0xff;
+	sector >>= 8;
+	ptr->bytes[1] = sector & 0xff;
+	sector >>= 8;
+	ptr->bytes[2] = sector & 0xff;
+}
+
+static inline unsigned int get_sector(SectorCount *ptr)
+{
+#if 1
+	unsigned int sector;
+
+	sector  = ptr->bytes[0];
+	sector += ptr->bytes[1] <<  8;
+	sector += ptr->bytes[2] << 16;
+
+	return sector;
+#else
+	/*  GET4 gets the next four bytes in Intel little endian order
+	 *  and converts them to host byte order and handles unaligned
+	 *  access.
+	 */
+	return (GET4(ptr, 0) & 0x00ffffff); /* back to host byte order */
+#endif
+}
+
+static void bsm_debug_fake(void)
+{
+	/* for testing of bad sector handling at end of tape
+	 */
+#if 0
+	ftape_put_bad_sector_entry(segments_per_track * tracks_per_tape - 3,
+				   0x000003e0;
+	ftape_put_bad_sector_entry(segments_per_track * tracks_per_tape - 2,
+				   0xff3fffff;
+	ftape_put_bad_sector_entry(segments_per_track * tracks_per_tape - 1,
+				   0xffffe000;
+#endif
+	/*  Enable to test bad sector handling
+	 */
+#if 0
+	ftape_put_bad_sector_entry(30, 0xfffffffe)
+	ftape_put_bad_sector_entry(32, 0x7fffffff);
+	ftape_put_bad_sector_entry(34, 0xfffeffff);
+	ftape_put_bad_sector_entry(36, 0x55555555);
+	ftape_put_bad_sector_entry(38, 0xffffffff);
+	ftape_put_bad_sector_entry(50, 0xffff0000);
+	ftape_put_bad_sector_entry(51, 0xffffffff);
+	ftape_put_bad_sector_entry(52, 0xffffffff);
+	ftape_put_bad_sector_entry(53, 0x0000ffff);
+#endif
+	/*  Enable when testing multiple volume tar dumps.
+	 */
+#if 0
+	{
+		int i;
+
+		for (i = ft_first_data_segment;
+		     i <= ft_last_data_segment - 7; ++i) {
+			ftape_put_bad_sector_entry(i, EMPTY_SEGMENT);
+		}
+	}
+#endif
+	/*  Enable when testing bit positions in *_error_map
+	 */
+#if 0
+	{
+		int i;
+		
+		for (i = first_data_segment; i <= last_data_segment; ++i) {
+			ftape_put_bad_sector_entry(i,
+					   ftape_get_bad_sector_entry(i) 
+					   | 0x00ff00ff);
+		}
+	}
+#endif
+}
+
+static void print_bad_sector_map(void)
+{
+	unsigned int good_sectors;
+	unsigned int total_bad = 0;
+	int i;
+	TRACE_FUN(ft_t_flow);
+
+	if (ft_format_code == fmt_big || 
+	    ft_format_code == fmt_var || 
+	    ft_format_code == fmt_1100ft) {
+		SectorCount *ptr = (SectorCount *)bad_sector_map;
+		unsigned int sector;
+		__u16 *ptr16;
+
+		while((sector = get_sector(ptr++)) != 0) {
+			if ((ft_format_code == fmt_big || 
+			     ft_format_code == fmt_var) &&
+			    sector & 0x800000) {
+				total_bad += FT_SECTORS_PER_SEGMENT - 3;
+				TRACE(ft_t_noise, "bad segment at sector: %6d",
+				      sector & 0x7fffff);
+			} else {
+				++total_bad;
+				TRACE(ft_t_noise, "bad sector: %6d", sector);
+			}
+		}
+		/*  Display old ftape's end-of-file marks
+		 */
+		ptr16 = (__u16*)ptr;
+		while ((sector = get_unaligned(ptr16++)) != 0) {
+			TRACE(ft_t_noise, "Old ftape eof mark: %4d/%2d",
+			      sector, get_unaligned(ptr16++));
+		}
+	} else { /* fixed size format */
+		for (i = ft_first_data_segment;
+		     i < (int)(ft_segments_per_track * ft_tracks_per_tape); ++i) {
+			SectorMap map = ((SectorMap *) bad_sector_map)[i];
+
+			if (map) {
+				TRACE(ft_t_noise,
+				      "bsm for segment %4d: 0x%08x", i, (unsigned int)map);
+				total_bad += ((map == EMPTY_SEGMENT)
+					       ? FT_SECTORS_PER_SEGMENT - 3
+					       : count_ones(map));
+			}
+		}
+	}
+	good_sectors =
+		((ft_segments_per_track * ft_tracks_per_tape - ft_first_data_segment)
+		 * (FT_SECTORS_PER_SEGMENT - 3)) - total_bad;
+	TRACE(ft_t_info, "%d Kb usable on this tape", good_sectors);
+	if (total_bad == 0) {
+		TRACE(ft_t_info,
+		      "WARNING: this tape has no bad blocks registered !");
+	} else {
+		TRACE(ft_t_info, "%d bad sectors", total_bad);
+	}
+	TRACE_EXIT;
+}
+
+
+void ftape_extract_bad_sector_map(__u8 * buffer)
+{
+	TRACE_FUN(ft_t_any);
+
+	/*  Fill the bad sector map with the contents of buffer.
+	 */
+	if (ft_format_code == fmt_var || ft_format_code == fmt_big) {
+		/* QIC-3010/3020 and wide QIC-80 tapes no longer have a failed
+		 * sector log but use this area to extend the bad sector map.
+		 */
+		bad_sector_map = &buffer[FT_HEADER_END];
+	} else {
+		/* non-wide QIC-80 tapes have a failed sector log area that
+		 * mustn't be included in the bad sector map.
+		 */
+		bad_sector_map = &buffer[FT_FSL + FT_FSL_SIZE];
+	}
+	if (ft_format_code == fmt_1100ft || 
+	    ft_format_code == fmt_var    ||
+	    ft_format_code == fmt_big) {
+		bsm_hash_ptr = (SectorCount *)bad_sector_map;
+	} else {
+		bsm_hash_ptr = NULL;
+	}
+	bsm_debug_fake();
+	if (TRACE_LEVEL >= ft_t_info) {
+		print_bad_sector_map();
+	}
+	TRACE_EXIT;
+}
+
+static inline SectorMap cvt2map(unsigned int sector)
+{
+	return 1 << (((sector & 0x7fffff) - 1) % FT_SECTORS_PER_SEGMENT);
+}
+
+static inline int cvt2segment(unsigned int sector)
+{
+	return ((sector & 0x7fffff) - 1) / FT_SECTORS_PER_SEGMENT;
+}
+
+static int forward_seek_entry(int segment_id, 
+			      SectorCount **ptr, 
+			      SectorMap *map)
+{
+	unsigned int sector;
+	int segment;
+
+	do {
+		sector = get_sector((*ptr)++);
+		segment = cvt2segment(sector);
+	} while (sector != 0 && segment < segment_id);
+	(*ptr) --; /* point to first sector >= segment_id */
+	/*  Get all sectors in segment_id
+	 */
+	if (sector == 0 || segment != segment_id) {
+		*map = 0;
+		return 0;
+	} else if ((sector & 0x800000) &&
+		   (ft_format_code == fmt_var || ft_format_code == fmt_big)) {
+		*map = EMPTY_SEGMENT;
+		return FT_SECTORS_PER_SEGMENT;
+	} else {
+		int count = 1;
+		SectorCount *tmp_ptr = (*ptr) + 1;
+		
+		*map = cvt2map(sector);
+		while ((sector = get_sector(tmp_ptr++)) != 0 &&
+		       (segment = cvt2segment(sector)) == segment_id) {
+			*map |= cvt2map(sector);
+			++count;
+		}
+		return count;
+	}
+}
+
+static int backwards_seek_entry(int segment_id,
+				SectorCount **ptr,
+				SectorMap *map)
+{
+	unsigned int sector;
+	int segment; /* max unsigned int */
+
+	if (*ptr <= (SectorCount *)bad_sector_map) {
+		*map = 0;
+		return 0;
+	}
+	do {
+		sector  = get_sector(--(*ptr));
+		segment = cvt2segment(sector);
+	} while (*ptr > (SectorCount *)bad_sector_map && segment > segment_id);
+	if (segment > segment_id) { /*  at start of list, no entry found */
+		*map = 0;
+		return 0;
+	} else if (segment < segment_id) {
+		/*  before smaller entry, adjust for overshoot */
+		(*ptr) ++;
+		*map = 0;
+		return 0;
+	} else if ((sector & 0x800000) &&
+		   (ft_format_code == fmt_big || ft_format_code == fmt_var)) {
+		*map = EMPTY_SEGMENT;
+		return FT_SECTORS_PER_SEGMENT;
+	} else { /*  get all sectors in segment_id */
+		int count = 1;
+
+		*map = cvt2map(sector);
+		while(*ptr > (SectorCount *)bad_sector_map) {
+			sector = get_sector(--(*ptr));
+			segment = cvt2segment(sector);
+			if (segment != segment_id) {
+				break;
+			}
+			*map |= cvt2map(sector);
+			++count;
+		}
+		if (segment < segment_id) {
+			(*ptr) ++;
+		}
+		return count;
+	}
+}
+
+#if 0
+static void ftape_put_bad_sector_entry(int segment_id, SectorMap new_map)
+{
+	SectorCount *ptr = (SectorCount *)bad_sector_map;
+	int count;
+	int new_count;
+	SectorMap map;
+	TRACE_FUN(ft_t_any);
+
+	if (ft_format_code == fmt_1100ft || 
+	    ft_format_code == fmt_var || 
+	    ft_format_code == fmt_big) {
+		count = forward_seek_entry(segment_id, &ptr, &map);
+		new_count = count_ones(new_map);
+		/* If format code == 4 put empty segment instead of 32
+		 * bad sectors.
+		 */
+		if (ft_format_code == fmt_var || ft_format_code == fmt_big) {
+			if (new_count == FT_SECTORS_PER_SEGMENT) {
+				new_count = 1;
+			}
+			if (count == FT_SECTORS_PER_SEGMENT) {
+				count = 1;
+			}
+		}
+		if (count != new_count) {
+			/* insert (or delete if < 0) new_count - count
+			 * entries.  Move trailing part of list
+			 * including terminating 0.
+			 */
+			SectorCount *hi_ptr = ptr;
+
+			do {
+			} while (get_sector(hi_ptr++) != 0);
+			/*  Note: ptr is of type byte *, and each bad sector
+			 *  consumes 3 bytes.
+			 */
+			memmove(ptr + new_count, ptr + count,
+				(size_t)(hi_ptr - (ptr + count))*sizeof(SectorCount));
+		}
+		TRACE(ft_t_noise, "putting map 0x%08x at %p, segment %d",
+		      (unsigned int)new_map, ptr, segment_id);
+		if (new_count == 1 && new_map == EMPTY_SEGMENT) {
+			put_sector(ptr++, (0x800001 + 
+					  segment_id * 
+					  FT_SECTORS_PER_SEGMENT));
+		} else {
+			int i = 0;
+
+			while (new_map) {
+				if (new_map & 1) {
+					put_sector(ptr++, 
+						   1 + segment_id * 
+						   FT_SECTORS_PER_SEGMENT + i);
+				}
+				++i;
+				new_map >>= 1;
+			}
+		}
+	} else {
+		((SectorMap *) bad_sector_map)[segment_id] = new_map;
+	}
+	TRACE_EXIT;
+}
+#endif  /*  0  */
+
+SectorMap ftape_get_bad_sector_entry(int segment_id)
+{
+	if (ft_used_header_segment == -1) {
+		/*  When reading header segment we'll need a blank map.
+		 */
+		return 0;
+	} else if (bsm_hash_ptr != NULL) {
+		/*  Invariants:
+		 *    map - mask value returned on last call.
+		 *    bsm_hash_ptr - points to first sector greater or equal to
+		 *          first sector in last_referenced segment.
+		 *    last_referenced - segment id used in the last call,
+		 *                      sector and map belong to this id.
+		 *  This code is designed for sequential access and retries.
+		 *  For true random access it may have to be redesigned.
+		 */
+		static int last_reference = -1;
+		static SectorMap map;
+
+		if (segment_id > last_reference) {
+			/*  Skip all sectors before segment_id
+			 */
+			forward_seek_entry(segment_id, &bsm_hash_ptr, &map);
+		} else if (segment_id < last_reference) {
+			/* Skip backwards until begin of buffer or
+			 * first sector in segment_id 
+			 */
+			backwards_seek_entry(segment_id, &bsm_hash_ptr, &map);
+		}		/* segment_id == last_reference : keep map */
+		last_reference = segment_id;
+		return map;
+	} else {
+		return ((SectorMap *) bad_sector_map)[segment_id];
+	}
+}
+
+/*  This is simply here to prevent us from overwriting other kernel
+ *  data. Writes will result in NULL Pointer dereference.
+ */
+void ftape_init_bsm(void)
+{
+	bad_sector_map = NULL;
+	bsm_hash_ptr   = NULL;
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-bsm.h b/drivers/char/ftape/lowlevel/ftape-bsm.h
new file mode 100644
index 0000000..ed45465
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-bsm.h
@@ -0,0 +1,66 @@
+#ifndef _FTAPE_BSM_H
+#define _FTAPE_BSM_H
+
+/*
+ * Copyright (C) 1994-1996 Bas Laarhoven,
+ *           (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-bsm.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:07 $
+ *
+ *      This file contains definitions for the bad sector map handling
+ *      routines for the QIC-117 floppy-tape driver for Linux.
+ */
+
+#include <linux/ftape.h>
+#include <linux/ftape-header-segment.h>
+
+#define EMPTY_SEGMENT           (0xffffffff)
+#define FAKE_SEGMENT            (0xfffffffe)
+
+/*  maximum (format code 4) bad sector map size (bytes).
+ */
+#define BAD_SECTOR_MAP_SIZE     (29 * SECTOR_SIZE - 256)
+
+/*  format code 4 bad sector entry, ftape uses this
+ *  internally for all format codes
+ */
+typedef __u32 SectorMap;
+/*  variable and 1100 ft bad sector map entry. These three bytes represent
+ *  a single sector address measured from BOT. 
+ */
+typedef struct NewSectorMap {          
+	__u8 bytes[3];
+} SectorCount;
+
+
+/*
+ *      ftape-bsm.c defined global vars.
+ */
+
+/*
+ *      ftape-bsm.c defined global functions.
+ */
+extern void update_bad_sector_map(__u8 * buffer);
+extern void ftape_extract_bad_sector_map(__u8 * buffer);
+extern SectorMap ftape_get_bad_sector_entry(int segment_id);
+extern __u8 *ftape_find_end_of_bsm_list(__u8 * address);
+extern void ftape_init_bsm(void);
+
+#endif
diff --git a/drivers/char/ftape/lowlevel/ftape-buffer.c b/drivers/char/ftape/lowlevel/ftape-buffer.c
new file mode 100644
index 0000000..54af20c
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-buffer.c
@@ -0,0 +1,129 @@
+/*
+ *      Copyright (C) 1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-buffer.c,v $
+ * $Revision: 1.3 $
+ * $Date: 1997/10/16 23:33:11 $
+ *
+ *  This file contains the allocator/dealloctor for ftape's dynamic dma
+ *  buffer.
+ */
+
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <asm/dma.h>
+
+#include <linux/ftape.h>
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-read.h"
+#include "../lowlevel/ftape-tracing.h"
+
+/*  DMA'able memory allocation stuff.
+ */
+
+static inline void *dmaalloc(size_t size)
+{
+	unsigned long addr;
+
+	if (size == 0) {
+		return NULL;
+	}
+	addr = __get_dma_pages(GFP_KERNEL, get_order(size));
+	if (addr) {
+		struct page *page;
+
+		for (page = virt_to_page(addr); page < virt_to_page(addr+size); page++)
+			SetPageReserved(page);
+	}
+	return (void *)addr;
+}
+
+static inline void dmafree(void *addr, size_t size)
+{
+	if (size > 0) {
+		struct page *page;
+
+		for (page = virt_to_page((unsigned long)addr);
+		     page < virt_to_page((unsigned long)addr+size); page++)
+			ClearPageReserved(page);
+		free_pages((unsigned long) addr, get_order(size));
+	}
+}
+
+static int add_one_buffer(void)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	if (ft_nr_buffers >= FT_MAX_NR_BUFFERS) {
+		TRACE_EXIT -ENOMEM;
+	}
+	ft_buffer[ft_nr_buffers] = kmalloc(sizeof(buffer_struct), GFP_KERNEL);
+	if (ft_buffer[ft_nr_buffers] == NULL) {
+		TRACE_EXIT -ENOMEM;
+	}
+	memset(ft_buffer[ft_nr_buffers], 0, sizeof(buffer_struct));
+	ft_buffer[ft_nr_buffers]->address = dmaalloc(FT_BUFF_SIZE);
+	if (ft_buffer[ft_nr_buffers]->address == NULL) {
+		kfree(ft_buffer[ft_nr_buffers]);
+		ft_buffer[ft_nr_buffers] = NULL;
+		TRACE_EXIT -ENOMEM;
+	}
+	ft_nr_buffers ++;
+	TRACE(ft_t_info, "buffer nr #%d @ %p, dma area @ %p",
+	      ft_nr_buffers,
+	      ft_buffer[ft_nr_buffers-1],
+	      ft_buffer[ft_nr_buffers-1]->address);
+	TRACE_EXIT 0;
+}
+
+static void del_one_buffer(void)
+{
+	TRACE_FUN(ft_t_flow);
+	if (ft_nr_buffers > 0) {
+		TRACE(ft_t_info, "releasing buffer nr #%d @ %p, dma area @ %p",
+		      ft_nr_buffers,
+		      ft_buffer[ft_nr_buffers-1],
+		      ft_buffer[ft_nr_buffers-1]->address);
+		ft_nr_buffers --;
+		dmafree(ft_buffer[ft_nr_buffers]->address, FT_BUFF_SIZE);
+		kfree(ft_buffer[ft_nr_buffers]);
+		ft_buffer[ft_nr_buffers] = NULL;
+	}
+	TRACE_EXIT;
+}
+
+int ftape_set_nr_buffers(int cnt)
+{
+	int delta = cnt - ft_nr_buffers;
+	TRACE_FUN(ft_t_flow);
+
+	if (delta > 0) {
+		while (delta--) {
+			if (add_one_buffer() < 0) {
+				TRACE_EXIT -ENOMEM;
+			}
+		}
+	} else if (delta < 0) {
+		while (delta++) {
+			del_one_buffer();
+		}
+	}
+	ftape_zap_read_buffers();
+	TRACE_EXIT 0;
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-buffer.h b/drivers/char/ftape/lowlevel/ftape-buffer.h
new file mode 100644
index 0000000..eec99ce
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-buffer.h
@@ -0,0 +1,32 @@
+#ifndef _FTAPE_BUFFER_H
+#define _FTAPE_BUFFER_H
+
+/*
+ *      Copyright (C) 1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-buffer.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:08 $
+ *
+ *  This file contains the allocator/dealloctor for ftape's dynamic dma
+ *  buffer.
+ */
+
+extern int  ftape_set_nr_buffers(int cnt);
+
+#endif
diff --git a/drivers/char/ftape/lowlevel/ftape-calibr.c b/drivers/char/ftape/lowlevel/ftape-calibr.c
new file mode 100644
index 0000000..956b258
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-calibr.c
@@ -0,0 +1,276 @@
+/*
+ *      Copyright (C) 1993-1996 Bas Laarhoven.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-calibr.c,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:08 $
+ *
+ *      GP calibration routine for processor speed dependent
+ *      functions.
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/jiffies.h>
+#include <asm/system.h>
+#include <asm/io.h>
+#if defined(__alpha__)
+# include <asm/hwrpb.h>
+#elif defined(__x86_64__)
+# include <asm/msr.h>
+# include <asm/timex.h>
+#elif defined(__i386__)
+# include <linux/timex.h>
+#endif
+#include <linux/ftape.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-calibr.h"
+#include "../lowlevel/fdc-io.h"
+
+#undef DEBUG
+
+#if !defined(__alpha__) && !defined(__i386__) && !defined(__x86_64__)
+# error Ftape is not implemented for this architecture!
+#endif
+
+#if defined(__alpha__) || defined(__x86_64__)
+static unsigned long ps_per_cycle = 0;
+#endif
+
+static spinlock_t calibr_lock;
+
+/*
+ * Note: On Intel PCs, the clock ticks at 100 Hz (HZ==100) which is
+ * too slow for certain timeouts (and that clock doesn't even tick
+ * when interrupts are disabled).  For that reason, the 8254 timer is
+ * used directly to implement fine-grained timeouts.  However, on
+ * Alpha PCs, the 8254 is *not* used to implement the clock tick
+ * (which is 1024 Hz, normally) and the 8254 timer runs at some
+ * "random" frequency (it seems to run at 18Hz, but it's not safe to
+ * rely on this value).  Instead, we use the Alpha's "rpcc"
+ * instruction to read cycle counts.  As this is a 32 bit counter,
+ * it will overflow only once per 30 seconds (on a 200MHz machine),
+ * which is plenty.
+ */
+
+unsigned int ftape_timestamp(void)
+{
+#if defined(__alpha__)
+	unsigned long r;
+
+	asm volatile ("rpcc %0" : "=r" (r));
+	return r;
+#elif defined(__x86_64__)
+	unsigned long r;
+	rdtscl(r);
+	return r;
+#elif defined(__i386__)
+
+/*
+ * Note that there is some time between counter underflowing and jiffies
+ * increasing, so the code below won't always give correct output.
+ * -Vojtech
+ */
+
+	unsigned long flags;
+	__u16 lo;
+	__u16 hi;
+
+	spin_lock_irqsave(&calibr_lock, flags);
+	outb_p(0x00, 0x43);	/* latch the count ASAP */
+	lo = inb_p(0x40);	/* read the latched count */
+	lo |= inb(0x40) << 8;
+	hi = jiffies;
+	spin_unlock_irqrestore(&calibr_lock, flags);
+	return ((hi + 1) * (unsigned int) LATCH) - lo;  /* downcounter ! */
+#endif
+}
+
+static unsigned int short_ftape_timestamp(void)
+{
+#if defined(__alpha__) || defined(__x86_64__)
+	return ftape_timestamp();
+#elif defined(__i386__)
+	unsigned int count;
+ 	unsigned long flags;
+ 
+	spin_lock_irqsave(&calibr_lock, flags);
+ 	outb_p(0x00, 0x43);	/* latch the count ASAP */
+	count = inb_p(0x40);	/* read the latched count */
+	count |= inb(0x40) << 8;
+	spin_unlock_irqrestore(&calibr_lock, flags);
+	return (LATCH - count);	/* normal: downcounter */
+#endif
+}
+
+static unsigned int diff(unsigned int t0, unsigned int t1)
+{
+#if defined(__alpha__) || defined(__x86_64__)
+	return (t1 - t0);
+#elif defined(__i386__)
+	/*
+	 * This is tricky: to work for both short and full ftape_timestamps
+	 * we'll have to discriminate between these.
+	 * If it _looks_ like short stamps with wrapping around we'll
+	 * asume it are. This will generate a small error if it really
+	 * was a (very large) delta from full ftape_timestamps.
+	 */
+	return (t1 <= t0 && t0 <= LATCH) ? t1 + LATCH - t0 : t1 - t0;
+#endif
+}
+
+static unsigned int usecs(unsigned int count)
+{
+#if defined(__alpha__) || defined(__x86_64__)
+	return (ps_per_cycle * count) / 1000000UL;
+#elif defined(__i386__)
+	return (10000 * count) / ((CLOCK_TICK_RATE + 50) / 100);
+#endif
+}
+
+unsigned int ftape_timediff(unsigned int t0, unsigned int t1)
+{
+	/*
+	 *  Calculate difference in usec for ftape_timestamp results t0 & t1.
+	 *  Note that on the i386 platform with short time-stamps, the
+	 *  maximum allowed timespan is 1/HZ or we'll lose ticks!
+	 */
+	return usecs(diff(t0, t1));
+}
+
+/*      To get an indication of the I/O performance,
+ *      measure the duration of the inb() function.
+ */
+static void time_inb(void)
+{
+	int i;
+	int t0, t1;
+	unsigned long flags;
+	int status;
+	TRACE_FUN(ft_t_any);
+
+	spin_lock_irqsave(&calibr_lock, flags);
+	t0 = short_ftape_timestamp();
+	for (i = 0; i < 1000; ++i) {
+		status = inb(fdc.msr);
+	}
+	t1 = short_ftape_timestamp();
+	spin_unlock_irqrestore(&calibr_lock, flags);
+	TRACE(ft_t_info, "inb() duration: %d nsec", ftape_timediff(t0, t1));
+	TRACE_EXIT;
+}
+
+static void init_clock(void)
+{
+	TRACE_FUN(ft_t_any);
+
+#if defined(__x86_64__)
+	ps_per_cycle = 1000000000UL / cpu_khz;
+#elif defined(__alpha__)
+	extern struct hwrpb_struct *hwrpb;
+	ps_per_cycle = (1000*1000*1000*1000UL) / hwrpb->cycle_freq;
+#endif
+	TRACE_EXIT;
+}
+
+/*
+ *      Input:  function taking int count as parameter.
+ *              pointers to calculated calibration variables.
+ */
+void ftape_calibrate(char *name,
+		    void (*fun) (unsigned int), 
+		    unsigned int *calibr_count, 
+		    unsigned int *calibr_time)
+{
+	static int first_time = 1;
+	int i;
+	unsigned int tc = 0;
+	unsigned int count;
+	unsigned int time;
+#if defined(__i386__)
+	unsigned int old_tc = 0;
+	unsigned int old_count = 1;
+	unsigned int old_time = 1;
+#endif
+	TRACE_FUN(ft_t_flow);
+
+	if (first_time) {             /* get idea of I/O performance */
+		init_clock();
+		time_inb();
+		first_time = 0;
+	}
+	/*    value of timeout must be set so that on very slow systems
+	 *    it will give a time less than one jiffy, and on
+	 *    very fast systems it'll give reasonable precision.
+	 */
+
+	count = 40;
+	for (i = 0; i < 15; ++i) {
+		unsigned int t0;
+		unsigned int t1;
+		unsigned int once;
+		unsigned int multiple;
+		unsigned long flags;
+
+		*calibr_count =
+		*calibr_time = count;	/* set TC to 1 */
+		spin_lock_irqsave(&calibr_lock, flags);
+		fun(0);		/* dummy, get code into cache */
+		t0 = short_ftape_timestamp();
+		fun(0);		/* overhead + one test */
+		t1 = short_ftape_timestamp();
+		once = diff(t0, t1);
+		t0 = short_ftape_timestamp();
+		fun(count);		/* overhead + count tests */
+		t1 = short_ftape_timestamp();
+		multiple = diff(t0, t1);
+		spin_unlock_irqrestore(&calibr_lock, flags);
+		time = ftape_timediff(0, multiple - once);
+		tc = (1000 * time) / (count - 1);
+		TRACE(ft_t_any, "once:%3d us,%6d times:%6d us, TC:%5d ns",
+			usecs(once), count - 1, usecs(multiple), tc);
+#if defined(__alpha__) || defined(__x86_64__)
+		/*
+		 * Increase the calibration count exponentially until the
+		 * calibration time exceeds 100 ms.
+		 */
+		if (time >= 100*1000) {
+			break;
+		}
+#elif defined(__i386__)
+		/*
+		 * increase the count until the resulting time nears 2/HZ,
+		 * then the tc will drop sharply because we lose LATCH counts.
+		 */
+		if (tc <= old_tc / 2) {
+			time = old_time;
+			count = old_count;
+			break;
+		}
+		old_tc = tc;
+		old_count = count;
+		old_time = time;
+#endif
+		count *= 2;
+	}
+	*calibr_count = count - 1;
+	*calibr_time  = time;
+	TRACE(ft_t_info, "TC for `%s()' = %d nsec (at %d counts)",
+	     name, (1000 * *calibr_time) / *calibr_count, *calibr_count);
+	TRACE_EXIT;
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-calibr.h b/drivers/char/ftape/lowlevel/ftape-calibr.h
new file mode 100644
index 0000000..0c7e752
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-calibr.h
@@ -0,0 +1,37 @@
+#ifndef _FTAPE_CALIBR_H
+#define _FTAPE_CALIBR_H
+
+/*
+ *      Copyright (C) 1993-1996 Bas Laarhoven.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-calibr.h,v $
+ * $Revision: 1.1 $
+ * $Date: 1997/09/19 09:05:26 $
+ *
+ *      This file contains a gp calibration routine for
+ *      hardware dependent timeout functions.
+ */
+
+extern void ftape_calibrate(char *name,
+			    void (*fun) (unsigned int),
+			    unsigned int *calibr_count,
+			    unsigned int *calibr_time);
+extern unsigned int ftape_timestamp(void);
+extern unsigned int ftape_timediff(unsigned int t0, unsigned int t1);
+
+#endif /* _FTAPE_CALIBR_H */
diff --git a/drivers/char/ftape/lowlevel/ftape-ctl.c b/drivers/char/ftape/lowlevel/ftape-ctl.c
new file mode 100644
index 0000000..32e0439
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-ctl.c
@@ -0,0 +1,897 @@
+/*
+ *      Copyright (C) 1993-1996 Bas Laarhoven,
+ *                    1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-ctl.c,v $
+ * $Revision: 1.4 $
+ * $Date: 1997/11/11 14:37:44 $
+ *
+ *      This file contains the non-read/write ftape functions for the
+ *      QIC-40/80/3010/3020 floppy-tape driver "ftape" for Linux.
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+
+#include <linux/ftape.h>
+#include <linux/qic117.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+
+/* ease porting between pre-2.4.x and later kernels */
+#define vma_get_pgoff(v)      ((v)->vm_pgoff)
+
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-write.h"
+#include "../lowlevel/ftape-read.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-bsm.h"
+
+/*      Global vars.
+ */
+ftape_info ftape_status = {
+/*  vendor information */
+	{ 0, },     /* drive type */
+/*  data rates */
+	500,        /* used data rate */
+	500,        /* drive max rate */
+	500,        /* fdc max rate   */
+/*  drive selection, either FTAPE_SEL_A/B/C/D */
+	-1,     /* drive selection */
+/*  flags set after decode the drive and tape status   */
+	0,          /* formatted */
+	1,          /* no tape */
+	1,          /* write protected */
+	1,          /* new tape */
+/*  values of last queried drive/tape status and error */
+	{{0,}},     /* last error code */
+	{{0,}},     /* drive status, configuration, tape status */
+/*  cartridge geometry */
+        20,         /* tracks_per_tape */
+        102,        /* segments_per_track */
+/*  location of header segments, etc. */
+	-1,     /* used_header_segment */
+	-1,     /* header_segment_1 */
+	-1,     /* header_segment_2 */
+	-1,     /* first_data_segment */
+        -1,     /* last_data_segment */
+/*  the format code as stored in the header segment  */
+	fmt_normal, /* format code */
+/*  the default for the qic std: unknown */
+	-1,
+/*  is tape running? */
+	idle,       /* runner_state */
+/*  is tape reading/writing/verifying/formatting/deleting */
+	idle,       /* driver state */
+/*  flags fatal hardware error */
+	1,          /* failure */
+/*  history record */
+	{ 0, }      /* history record */
+};
+	
+int ftape_segments_per_head     = 1020;
+int ftape_segments_per_cylinder = 4;
+int ftape_init_drive_needed = 1; /* need to be global for ftape_reset_drive()
+				  * in ftape-io.c
+				  */
+
+/*      Local vars.
+ */
+static const vendor_struct vendors[] = QIC117_VENDORS;
+static const wakeup_method methods[] = WAKEUP_METHODS;
+
+const ftape_info *ftape_get_status(void)
+{
+#if defined(STATUS_PARANOYA)
+	static ftape_info get_status;
+
+	get_status = ftape_status;
+	return &get_status;
+#else
+	return &ftape_status; /*  maybe return only a copy of it to assure 
+			       *  read only access
+			       */
+#endif
+}
+
+static int ftape_not_operational(int status)
+{
+	/* return true if status indicates tape can not be used.
+	 */
+	return ((status ^ QIC_STATUS_CARTRIDGE_PRESENT) &
+		(QIC_STATUS_ERROR |
+		 QIC_STATUS_CARTRIDGE_PRESENT |
+		 QIC_STATUS_NEW_CARTRIDGE));
+}
+
+int ftape_seek_to_eot(void)
+{
+	int status;
+	TRACE_FUN(ft_t_any);
+
+	TRACE_CATCH(ftape_ready_wait(ftape_timeout.pause, &status),);
+	while ((status & QIC_STATUS_AT_EOT) == 0) {
+		if (ftape_not_operational(status)) {
+			TRACE_EXIT -EIO;
+		}
+		TRACE_CATCH(ftape_command_wait(QIC_PHYSICAL_FORWARD,
+					       ftape_timeout.rewind,&status),);
+	}
+	TRACE_EXIT 0;
+}
+
+int ftape_seek_to_bot(void)
+{
+	int status;
+	TRACE_FUN(ft_t_any);
+
+	TRACE_CATCH(ftape_ready_wait(ftape_timeout.pause, &status),);
+	while ((status & QIC_STATUS_AT_BOT) == 0) {
+		if (ftape_not_operational(status)) {
+			TRACE_EXIT -EIO;
+		}
+		TRACE_CATCH(ftape_command_wait(QIC_PHYSICAL_REVERSE,
+					       ftape_timeout.rewind,&status),);
+	}
+	TRACE_EXIT 0;
+}
+
+static int ftape_new_cartridge(void)
+{
+	ft_location.track = -1; /* force seek on first access */
+	ftape_zap_read_buffers();
+	ftape_zap_write_buffers();
+	return 0;
+}
+
+int ftape_abort_operation(void)
+{
+	int result = 0;
+	int status;
+	TRACE_FUN(ft_t_flow);
+
+	if (ft_runner_status == running) {
+		TRACE(ft_t_noise, "aborting runner, waiting");
+		
+		ft_runner_status = do_abort;
+		/* set timeout so that the tape will run to logical EOT
+		 * if we missed the last sector and there are no queue pulses.
+		 */
+		result = ftape_dumb_stop();
+	}
+	if (ft_runner_status != idle) {
+		if (ft_runner_status == do_abort) {
+			TRACE(ft_t_noise, "forcing runner abort");
+		}
+		TRACE(ft_t_noise, "stopping tape");
+		result = ftape_stop_tape(&status);
+		ft_location.known = 0;
+		ft_runner_status  = idle;
+	}
+	ftape_reset_buffer();
+	ftape_zap_read_buffers();
+	ftape_set_state(idle);
+	TRACE_EXIT result;
+}
+
+static int lookup_vendor_id(unsigned int vendor_id)
+{
+	int i = 0;
+
+	while (vendors[i].vendor_id != vendor_id) {
+		if (++i >= NR_ITEMS(vendors)) {
+			return -1;
+		}
+	}
+	return i;
+}
+
+static void ftape_detach_drive(void)
+{
+	TRACE_FUN(ft_t_any);
+
+	TRACE(ft_t_flow, "disabling tape drive and fdc");
+	ftape_put_drive_to_sleep(ft_drive_type.wake_up);
+	fdc_catch_stray_interrupts(1);	/* one always comes */
+	fdc_disable();
+	fdc_release_irq_and_dma();
+	fdc_release_regions();
+	TRACE_EXIT;
+}
+
+static void clear_history(void)
+{
+	ft_history.used = 0;
+	ft_history.id_am_errors =
+		ft_history.id_crc_errors =
+		ft_history.data_am_errors =
+		ft_history.data_crc_errors =
+		ft_history.overrun_errors =
+		ft_history.no_data_errors =
+		ft_history.retries =
+		ft_history.crc_errors =
+		ft_history.crc_failures =
+		ft_history.ecc_failures =
+		ft_history.corrected =
+		ft_history.defects =
+		ft_history.rewinds = 0;
+}
+
+static int ftape_activate_drive(vendor_struct * drive_type)
+{
+	int result = 0;
+	TRACE_FUN(ft_t_flow);
+
+	/* If we already know the drive type, wake it up.
+	 * Else try to find out what kind of drive is attached.
+	 */
+	if (drive_type->wake_up != unknown_wake_up) {
+		TRACE(ft_t_flow, "enabling tape drive and fdc");
+		result = ftape_wakeup_drive(drive_type->wake_up);
+		if (result < 0) {
+			TRACE(ft_t_err, "known wakeup method failed");
+		}
+	} else {
+		wake_up_types method;
+		const ft_trace_t old_tracing = TRACE_LEVEL;
+		if (TRACE_LEVEL < ft_t_flow) {
+			SET_TRACE_LEVEL(ft_t_bug);
+		}
+
+		/*  Try to awaken the drive using all known methods.
+		 *  Lower tracing for a while.
+		 */
+		for (method=no_wake_up; method < NR_ITEMS(methods); ++method) {
+			drive_type->wake_up = method;
+#ifdef CONFIG_FT_TWO_DRIVES
+			/*  Test setup for dual drive configuration.
+			 *  /dev/rft2 uses mountain wakeup
+			 *  /dev/rft3 uses colorado wakeup
+			 *  Other systems will use the normal scheme.
+			 */
+			if ((ft_drive_sel < 2)                            ||
+			    (ft_drive_sel == 2 && method == FT_WAKE_UP_1) ||
+			    (ft_drive_sel == 3 && method == FT_WAKE_UP_2)) {
+				result=ftape_wakeup_drive(drive_type->wake_up);
+			} else {
+				result = -EIO;
+			}
+#else
+			result = ftape_wakeup_drive(drive_type->wake_up);
+#endif
+			if (result >= 0) {
+				TRACE(ft_t_warn, "drive wakeup method: %s",
+				      methods[drive_type->wake_up].name);
+				break;
+			}
+		}
+		SET_TRACE_LEVEL(old_tracing);
+
+		if (method >= NR_ITEMS(methods)) {
+			/* no response at all, cannot open this drive */
+			drive_type->wake_up = unknown_wake_up;
+			TRACE(ft_t_err, "no tape drive found !");
+			result = -ENODEV;
+		}
+	}
+	TRACE_EXIT result;
+}
+
+static int ftape_get_drive_status(void)
+{
+	int result;
+	int status;
+	TRACE_FUN(ft_t_flow);
+
+	ft_no_tape = ft_write_protected = 0;
+	/*    Tape drive is activated now.
+	 *    First clear error status if present.
+	 */
+	do {
+		result = ftape_ready_wait(ftape_timeout.reset, &status);
+		if (result < 0) {
+			if (result == -ETIME) {
+				TRACE(ft_t_err, "ftape_ready_wait timeout");
+			} else if (result == -EINTR) {
+				TRACE(ft_t_err, "ftape_ready_wait aborted");
+			} else {
+				TRACE(ft_t_err, "ftape_ready_wait failed");
+			}
+			TRACE_EXIT -EIO;
+		}
+		/*  Clear error condition (drive is ready !)
+		 */
+		if (status & QIC_STATUS_ERROR) {
+			unsigned int error;
+			qic117_cmd_t command;
+
+			TRACE(ft_t_err, "error status set");
+			result = ftape_report_error(&error, &command, 1);
+			if (result < 0) {
+				TRACE(ft_t_err,
+				      "report_error_code failed: %d", result);
+				/* hope it's working next time */
+				ftape_reset_drive();
+				TRACE_EXIT -EIO;
+			} else if (error != 0) {
+				TRACE(ft_t_noise, "error code   : %d", error);
+				TRACE(ft_t_noise, "error command: %d", command);
+			}
+		}
+		if (status & QIC_STATUS_NEW_CARTRIDGE) {
+			unsigned int error;
+			qic117_cmd_t command;
+			const ft_trace_t old_tracing = TRACE_LEVEL;
+			SET_TRACE_LEVEL(ft_t_bug);
+
+			/*  Undocumented feature: Must clear (not present!)
+			 *  error here or we'll fail later.
+			 */
+			ftape_report_error(&error, &command, 1);
+
+			SET_TRACE_LEVEL(old_tracing);
+			TRACE(ft_t_info, "status: new cartridge");
+			ft_new_tape = 1;
+		} else {
+			ft_new_tape = 0;
+		}
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+	} while (status & QIC_STATUS_ERROR);
+	
+	ft_no_tape = !(status & QIC_STATUS_CARTRIDGE_PRESENT);
+	ft_write_protected = (status & QIC_STATUS_WRITE_PROTECT) != 0;
+	if (ft_no_tape) {
+		TRACE(ft_t_warn, "no cartridge present");
+	} else {
+		if (ft_write_protected) {
+			TRACE(ft_t_noise, "Write protected cartridge");
+		}
+	}
+	TRACE_EXIT 0;
+}
+
+static void ftape_log_vendor_id(void)
+{
+	int vendor_index;
+	TRACE_FUN(ft_t_flow);
+
+	ftape_report_vendor_id(&ft_drive_type.vendor_id);
+	vendor_index = lookup_vendor_id(ft_drive_type.vendor_id);
+	if (ft_drive_type.vendor_id == UNKNOWN_VENDOR &&
+	    ft_drive_type.wake_up == wake_up_colorado) {
+		vendor_index = 0;
+		/* hack to get rid of all this mail */
+		ft_drive_type.vendor_id = 0;
+	}
+	if (vendor_index < 0) {
+		/* Unknown vendor id, first time opening device.  The
+		 * drive_type remains set to type found at wakeup
+		 * time, this will probably keep the driver operating
+		 * for this new vendor.  
+		 */
+		TRACE(ft_t_warn, "\n"
+		      KERN_INFO "============ unknown vendor id ===========\n"
+		      KERN_INFO "A new, yet unsupported tape drive is found\n"
+		      KERN_INFO "Please report the following values:\n"
+		      KERN_INFO "   Vendor id     : 0x%04x\n"
+		      KERN_INFO "   Wakeup method : %s\n"
+		      KERN_INFO "And a description of your tape drive\n"
+		      KERN_INFO "to "THE_FTAPE_MAINTAINER"\n"
+		      KERN_INFO "==========================================",
+		      ft_drive_type.vendor_id,
+		      methods[ft_drive_type.wake_up].name);
+		ft_drive_type.speed = 0;		/* unknown */
+	} else {
+		ft_drive_type.name  = vendors[vendor_index].name;
+		ft_drive_type.speed = vendors[vendor_index].speed;
+		TRACE(ft_t_info, "tape drive type: %s", ft_drive_type.name);
+		/* scan all methods for this vendor_id in table */
+		while(ft_drive_type.wake_up != vendors[vendor_index].wake_up) {
+			if (vendor_index < NR_ITEMS(vendors) - 1 &&
+			    vendors[vendor_index + 1].vendor_id 
+			    == 
+			    ft_drive_type.vendor_id) {
+				++vendor_index;
+			} else {
+				break;
+			}
+		}
+		if (ft_drive_type.wake_up != vendors[vendor_index].wake_up) {
+			TRACE(ft_t_warn, "\n"
+		     KERN_INFO "==========================================\n"
+		     KERN_INFO "wakeup type mismatch:\n"
+		     KERN_INFO "found: %s, expected: %s\n"
+		     KERN_INFO "please report this to "THE_FTAPE_MAINTAINER"\n"
+		     KERN_INFO "==========================================",
+			      methods[ft_drive_type.wake_up].name,
+			      methods[vendors[vendor_index].wake_up].name);
+		}
+	}
+	TRACE_EXIT;
+}
+
+void ftape_calc_timeouts(unsigned int qic_std,
+			 unsigned int data_rate,
+			 unsigned int tape_len)
+{
+	int speed;		/* deci-ips ! */
+	int ff_speed;
+	int length;
+	TRACE_FUN(ft_t_any);
+
+	/*                           tape transport speed
+	 *  data rate:        QIC-40   QIC-80   QIC-3010 QIC-3020
+	 *
+	 *    250 Kbps        25 ips     n/a      n/a      n/a
+	 *    500 Kbps        50 ips   34 ips   22.6 ips   n/a
+	 *      1 Mbps          n/a    68 ips   45.2 ips 22.6 ips
+	 *      2 Mbps          n/a      n/a      n/a    45.2 ips
+	 *
+	 *  fast tape transport speed is at least 68 ips.
+	 */
+	switch (qic_std) {
+	case QIC_TAPE_QIC40:
+		speed = (data_rate == 250) ? 250 : 500;
+		break;
+	case QIC_TAPE_QIC80:
+		speed = (data_rate == 500) ? 340 : 680;
+		break;
+	case QIC_TAPE_QIC3010:
+		speed = (data_rate == 500) ? 226 : 452;
+		break;
+	case QIC_TAPE_QIC3020:
+		speed = (data_rate == 1000) ? 226 : 452;
+		break;
+	default:
+		TRACE(ft_t_bug, "Unknown qic_std (bug) ?");
+		speed = 500;
+		break;
+	}
+	if (ft_drive_type.speed == 0) {
+		unsigned long t0;
+		static int dt = 0;     /* keep gcc from complaining */
+		static int first_time = 1;
+
+		/*  Measure the time it takes to wind to EOT and back to BOT.
+		 *  If the tape length is known, calculate the rewind speed.
+		 *  Else keep the time value for calculation of the rewind
+		 *  speed later on, when the length _is_ known.
+		 *  Ask for a report only when length and speed are both known.
+		 */
+		if (first_time) {
+			ftape_seek_to_bot();
+			t0 = jiffies;
+			ftape_seek_to_eot();
+			ftape_seek_to_bot();
+			dt = (int) (((jiffies - t0) * FT_USPT) / 1000);
+			if (dt < 1) {
+				dt = 1;	/* prevent div by zero on failures */
+			}
+			first_time = 0;
+			TRACE(ft_t_info,
+			      "trying to determine seek timeout, got %d msec",
+			      dt);
+		}
+		if (tape_len != 0) {
+			ft_drive_type.speed = 
+				(2 * 12 * tape_len * 1000) / dt;
+			TRACE(ft_t_warn, "\n"
+		     KERN_INFO "==========================================\n"
+		     KERN_INFO "drive type: %s\n"
+		     KERN_INFO "delta time = %d ms, length = %d ft\n"
+		     KERN_INFO "has a maximum tape speed of %d ips\n"
+		     KERN_INFO "please report this to "THE_FTAPE_MAINTAINER"\n"
+		     KERN_INFO "==========================================",
+			      ft_drive_type.name, dt, tape_len, 
+			      ft_drive_type.speed);
+		}
+	}
+	/*  Handle unknown length tapes as very long ones. We'll
+	 *  determine the actual length from a header segment later.
+	 *  This is normal for all modern (Wide,TR1/2/3) formats.
+	 */
+	if (tape_len <= 0) {
+		TRACE(ft_t_noise,
+		      "Unknown tape length, using maximal timeouts");
+		length = QIC_TOP_TAPE_LEN;	/* use worst case values */
+	} else {
+		length = tape_len;		/* use actual values */
+	}
+	if (ft_drive_type.speed == 0) {
+		ff_speed = speed; 
+	} else {
+		ff_speed = ft_drive_type.speed;
+	}
+	/*  time to go from bot to eot at normal speed (data rate):
+	 *  time = (1+delta) * length (ft) * 12 (inch/ft) / speed (ips)
+	 *  delta = 10 % for seek speed, 20 % for rewind speed.
+	 */
+	ftape_timeout.seek = (length * 132 * FT_SECOND) / speed;
+	ftape_timeout.rewind = (length * 144 * FT_SECOND) / (10 * ff_speed);
+	ftape_timeout.reset = 20 * FT_SECOND + ftape_timeout.rewind;
+	TRACE(ft_t_noise, "timeouts for speed = %d, length = %d\n"
+	      KERN_INFO "seek timeout  : %d sec\n"
+	      KERN_INFO "rewind timeout: %d sec\n"
+	      KERN_INFO "reset timeout : %d sec",
+	      speed, length,
+	      (ftape_timeout.seek + 500) / 1000,
+	      (ftape_timeout.rewind + 500) / 1000,
+	      (ftape_timeout.reset + 500) / 1000);
+	TRACE_EXIT;
+}
+
+/* This function calibrates the datarate (i.e. determines the maximal
+ * usable data rate) and sets the global variable ft_qic_std to qic_std
+ *
+ */
+int ftape_calibrate_data_rate(unsigned int qic_std)
+{
+	int rate = ft_fdc_rate_limit;
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	ft_qic_std = qic_std;
+
+	if (ft_qic_std == -1) {
+		TRACE_ABORT(-EIO, ft_t_err,
+		"Unable to determine data rate if QIC standard is unknown");
+	}
+
+	/*  Select highest rate supported by both fdc and drive.
+	 *  Start with highest rate supported by the fdc.
+	 */
+	while (fdc_set_data_rate(rate) < 0 && rate > 250) {
+		rate /= 2;
+	}
+	TRACE(ft_t_info,
+	      "Highest FDC supported data rate: %d Kbps", rate);
+	ft_fdc_max_rate = rate;
+	do {
+		result = ftape_set_data_rate(rate, ft_qic_std);
+	} while (result == -EINVAL && (rate /= 2) > 250);
+	if (result < 0) {
+		TRACE_ABORT(-EIO, ft_t_err, "set datarate failed");
+	}
+	ft_data_rate = rate;
+	TRACE_EXIT 0;
+}
+
+static int ftape_init_drive(void)
+{
+	int status;
+	qic_model model;
+	unsigned int qic_std;
+	unsigned int data_rate;
+	TRACE_FUN(ft_t_flow);
+
+	ftape_init_drive_needed = 0; /* don't retry if this fails ? */
+	TRACE_CATCH(ftape_report_raw_drive_status(&status),);
+	if (status & QIC_STATUS_CARTRIDGE_PRESENT) {
+		if (!(status & QIC_STATUS_AT_BOT)) {
+			/*  Antique drives will get here after a soft reset,
+			 *  modern ones only if the driver is loaded when the
+			 *  tape wasn't rewound properly.
+			 */
+			/* Tape should be at bot if new cartridge ! */
+			ftape_seek_to_bot();
+		}
+		if (!(status & QIC_STATUS_REFERENCED)) {
+			TRACE(ft_t_flow, "starting seek_load_point");
+			TRACE_CATCH(ftape_command_wait(QIC_SEEK_LOAD_POINT,
+						       ftape_timeout.reset,
+						       &status),);
+		}
+	}
+	ft_formatted = (status & QIC_STATUS_REFERENCED) != 0;
+	if (!ft_formatted) {
+		TRACE(ft_t_warn, "Warning: tape is not formatted !");
+	}
+
+	/*  report configuration aborts when ftape_tape_len == -1
+	 *  unknown qic_std is okay if not formatted.
+	 */
+	TRACE_CATCH(ftape_report_configuration(&model,
+					       &data_rate,
+					       &qic_std,
+					       &ftape_tape_len),);
+
+	/*  Maybe add the following to the /proc entry
+	 */
+	TRACE(ft_t_info, "%s drive @ %d Kbps",
+	      (model == prehistoric) ? "prehistoric" :
+	      ((model == pre_qic117c) ? "pre QIC-117C" :
+	       ((model == post_qic117b) ? "post QIC-117B" :
+		"post QIC-117D")), data_rate);
+
+	if (ft_formatted) {
+		/*  initialize ft_used_data_rate to maximum value 
+		 *  and set ft_qic_std
+		 */
+		TRACE_CATCH(ftape_calibrate_data_rate(qic_std),);
+		if (ftape_tape_len == 0) {
+			TRACE(ft_t_info, "unknown length QIC-%s tape",
+			      (ft_qic_std == QIC_TAPE_QIC40) ? "40" :
+			      ((ft_qic_std == QIC_TAPE_QIC80) ? "80" :
+			       ((ft_qic_std == QIC_TAPE_QIC3010) 
+				? "3010" : "3020")));
+		} else {
+			TRACE(ft_t_info, "%d ft. QIC-%s tape", ftape_tape_len,
+			      (ft_qic_std == QIC_TAPE_QIC40) ? "40" :
+			      ((ft_qic_std == QIC_TAPE_QIC80) ? "80" :
+			       ((ft_qic_std == QIC_TAPE_QIC3010)
+				? "3010" : "3020")));
+		}
+		ftape_calc_timeouts(ft_qic_std, ft_data_rate, ftape_tape_len);
+		/* soft write-protect QIC-40/QIC-80 cartridges used with a
+		 * Colorado T3000 drive. Buggy hardware!
+		 */
+		if ((ft_drive_type.vendor_id == 0x011c6) &&
+		    ((ft_qic_std == QIC_TAPE_QIC40 ||
+		      ft_qic_std == QIC_TAPE_QIC80) &&
+		     !ft_write_protected)) {
+			TRACE(ft_t_warn, "\n"
+	KERN_INFO "The famous Colorado T3000 bug:\n"
+	KERN_INFO "%s drives can't write QIC40 and QIC80\n"
+	KERN_INFO "cartridges but don't set the write-protect flag!",
+			      ft_drive_type.name);
+			ft_write_protected = 1;
+		}
+	} else {
+		/*  Doesn't make too much sense to set the data rate
+		 *  because we don't know what to use for the write
+		 *  precompensation.
+		 *  Need to do this again when formatting the cartridge.
+		 */
+		ft_data_rate = data_rate;
+		ftape_calc_timeouts(QIC_TAPE_QIC40,
+				    data_rate,
+				    ftape_tape_len);
+	}
+	ftape_new_cartridge();
+	TRACE_EXIT 0;
+}
+
+static void ftape_munmap(void)
+{
+	int i;
+	TRACE_FUN(ft_t_flow);
+	
+	for (i = 0; i < ft_nr_buffers; i++) {
+		ft_buffer[i]->mmapped = 0;
+	}
+	TRACE_EXIT;
+}
+
+/*   Map the dma buffers into the virtual address range given by vma.
+ *   We only check the caller doesn't map non-existent buffers. We
+ *   don't check for multiple mappings.
+ */
+int ftape_mmap(struct vm_area_struct *vma)
+{
+	int num_buffers;
+	int i;
+	TRACE_FUN(ft_t_flow);
+	
+	if (ft_failure) {
+		TRACE_EXIT -ENODEV;
+	}
+	if (!(vma->vm_flags & (VM_READ|VM_WRITE))) {
+		TRACE_ABORT(-EINVAL, ft_t_err, "Undefined mmap() access");
+	}
+	if (vma_get_pgoff(vma) != 0) {
+		TRACE_ABORT(-EINVAL, ft_t_err, "page offset must be 0");
+	}
+	if ((vma->vm_end - vma->vm_start) % FT_BUFF_SIZE != 0) {
+		TRACE_ABORT(-EINVAL, ft_t_err,
+			    "size = %ld, should be a multiple of %d",
+			    vma->vm_end - vma->vm_start,
+			    FT_BUFF_SIZE);
+	}
+	num_buffers = (vma->vm_end - vma->vm_start) / FT_BUFF_SIZE;
+	if (num_buffers > ft_nr_buffers) {
+		TRACE_ABORT(-EINVAL,
+			    ft_t_err, "size = %ld, should be less than %d",
+			    vma->vm_end - vma->vm_start,
+			    ft_nr_buffers * FT_BUFF_SIZE);
+	}
+	if (ft_driver_state != idle) {
+		/* this also clears the buffer states 
+		 */
+		ftape_abort_operation();
+	} else {
+		ftape_reset_buffer();
+	}
+	for (i = 0; i < num_buffers; i++) {
+		unsigned long pfn;
+
+		pfn = virt_to_phys(ft_buffer[i]->address) >> PAGE_SHIFT;
+		TRACE_CATCH(remap_pfn_range(vma, vma->vm_start +
+					     i * FT_BUFF_SIZE,
+					     pfn,
+					     FT_BUFF_SIZE,
+					     vma->vm_page_prot),
+			    _res = -EAGAIN);
+		TRACE(ft_t_noise, "remapped dma buffer @ %p to location @ %p",
+		      ft_buffer[i]->address,
+		      (void *)(vma->vm_start + i * FT_BUFF_SIZE));
+	}
+	for (i = 0; i < num_buffers; i++) {
+		memset(ft_buffer[i]->address, 0xAA, FT_BUFF_SIZE);
+		ft_buffer[i]->mmapped++;
+	}	
+	TRACE_EXIT 0;
+}
+
+static void ftape_init_driver(void); /* forward declaration */
+
+/*      OPEN routine called by kernel-interface code
+ */
+int ftape_enable(int drive_selection)
+{
+	TRACE_FUN(ft_t_any);
+
+	if (ft_drive_sel == -1 || ft_drive_sel != drive_selection) {
+		/* Other selection than last time
+		 */
+		ftape_init_driver();
+	}
+	ft_drive_sel = FTAPE_SEL(drive_selection);
+	ft_failure = 0;
+	TRACE_CATCH(fdc_init(),); /* init & detect fdc */
+	TRACE_CATCH(ftape_activate_drive(&ft_drive_type),
+		    fdc_disable();
+		    fdc_release_irq_and_dma();
+		    fdc_release_regions());
+	TRACE_CATCH(ftape_get_drive_status(), ftape_detach_drive());
+	if (ft_drive_type.vendor_id == UNKNOWN_VENDOR) {
+		ftape_log_vendor_id();
+	}
+	if (ft_new_tape) {
+		ftape_init_drive_needed = 1;
+	}
+	if (!ft_no_tape && ftape_init_drive_needed) {
+		TRACE_CATCH(ftape_init_drive(), ftape_detach_drive());
+	}
+	ftape_munmap(); /* clear the mmap flag */
+	clear_history();
+	TRACE_EXIT 0;
+}
+
+/*   release routine called by the high level interface modules
+ *   zftape or sftape.
+ */
+void ftape_disable(void)
+{
+	int i;
+	TRACE_FUN(ft_t_any);
+
+	for (i = 0; i < ft_nr_buffers; i++) {
+		if (ft_buffer[i]->mmapped) {
+			TRACE(ft_t_noise, "first byte of buffer %d: 0x%02x",
+			      i, *ft_buffer[i]->address);
+		}
+	}
+	if (sigtestsetmask(&current->pending.signal, _DONT_BLOCK) && 
+	    !(sigtestsetmask(&current->pending.signal, _NEVER_BLOCK)) &&
+	    ftape_tape_running) {
+		TRACE(ft_t_warn,
+		      "Interrupted by fatal signal and tape still running");
+		ftape_dumb_stop();
+		ftape_abort_operation(); /* it's annoying */
+	} else {
+		ftape_set_state(idle);
+	}
+	ftape_detach_drive();
+	if (ft_history.used) {
+		TRACE(ft_t_info, "== Non-fatal errors this run: ==");
+		TRACE(ft_t_info, "fdc isr statistics:\n"
+		      KERN_INFO " id_am_errors     : %3d\n"
+		      KERN_INFO " id_crc_errors    : %3d\n"
+		      KERN_INFO " data_am_errors   : %3d\n"
+		      KERN_INFO " data_crc_errors  : %3d\n"
+		      KERN_INFO " overrun_errors   : %3d\n"
+		      KERN_INFO " no_data_errors   : %3d\n"
+		      KERN_INFO " retries          : %3d",
+		      ft_history.id_am_errors,   ft_history.id_crc_errors,
+		      ft_history.data_am_errors, ft_history.data_crc_errors,
+		      ft_history.overrun_errors, ft_history.no_data_errors,
+		      ft_history.retries);
+		if (ft_history.used & 1) {
+			TRACE(ft_t_info, "ecc statistics:\n"
+			      KERN_INFO " crc_errors       : %3d\n"
+			      KERN_INFO " crc_failures     : %3d\n"
+			      KERN_INFO " ecc_failures     : %3d\n"
+			      KERN_INFO " sectors corrected: %3d",
+			      ft_history.crc_errors,   ft_history.crc_failures,
+			      ft_history.ecc_failures, ft_history.corrected);
+		}
+		if (ft_history.defects > 0) {
+			TRACE(ft_t_warn, "Warning: %d media defects!",
+			      ft_history.defects);
+		}
+		if (ft_history.rewinds > 0) {
+			TRACE(ft_t_info, "tape motion statistics:\n"
+			      KERN_INFO "repositions       : %3d",
+			      ft_history.rewinds);
+		}
+	}
+	ft_failure = 1;
+	TRACE_EXIT;
+}
+
+static void ftape_init_driver(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	ft_drive_type.vendor_id = UNKNOWN_VENDOR;
+	ft_drive_type.speed     = 0;
+	ft_drive_type.wake_up   = unknown_wake_up;
+	ft_drive_type.name      = "Unknown";
+
+	ftape_timeout.seek      = 650 * FT_SECOND;
+	ftape_timeout.reset     = 670 * FT_SECOND;
+	ftape_timeout.rewind    = 650 * FT_SECOND;
+	ftape_timeout.head_seek =  15 * FT_SECOND;
+	ftape_timeout.stop      =   5 * FT_SECOND;
+	ftape_timeout.pause     =  16 * FT_SECOND;
+
+	ft_qic_std             = -1;
+	ftape_tape_len         = 0;  /* unknown */
+	ftape_current_command  = 0;
+	ftape_current_cylinder = -1;
+
+	ft_segments_per_track       = 102;
+	ftape_segments_per_head     = 1020;
+	ftape_segments_per_cylinder = 4;
+	ft_tracks_per_tape          = 20;
+
+	ft_failure = 1;
+
+	ft_formatted       = 0;
+	ft_no_tape         = 1;
+	ft_write_protected = 1;
+	ft_new_tape        = 1;
+
+	ft_driver_state = idle;
+
+	ft_data_rate = 
+		ft_fdc_max_rate   = 500;
+	ft_drive_max_rate = 0; /* triggers set_rate_test() */
+
+	ftape_init_drive_needed = 1;
+
+	ft_header_segment_1    = -1;
+	ft_header_segment_2    = -1;
+	ft_used_header_segment = -1;
+	ft_first_data_segment  = -1;
+	ft_last_data_segment   = -1;
+
+	ft_location.track = -1;
+	ft_location.known = 0;
+
+	ftape_tape_running = 0;
+	ftape_might_be_off_track = 1;
+
+	ftape_new_cartridge();	/* init some tape related variables */
+	ftape_init_bsm();
+	TRACE_EXIT;
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-ctl.h b/drivers/char/ftape/lowlevel/ftape-ctl.h
new file mode 100644
index 0000000..5f5e30b
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-ctl.h
@@ -0,0 +1,162 @@
+#ifndef _FTAPE_CTL_H
+#define _FTAPE_CTL_H
+
+/*
+ * Copyright (C) 1993-1996 Bas Laarhoven,
+ *           (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-ctl.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:09 $
+ *
+ *      This file contains the non-standard IOCTL related definitions
+ *      for the QIC-40/80/3010/3020 floppy-tape driver "ftape" for
+ *      Linux.
+ */
+
+#include <linux/ioctl.h>
+#include <linux/mtio.h>
+#include <linux/ftape-vendors.h>
+
+#include "../lowlevel/ftape-rw.h"
+#include <linux/ftape-header-segment.h>
+
+typedef struct {
+	int used;		/* any reading or writing done */
+	/* isr statistics */
+	unsigned int id_am_errors;	/* id address mark not found */
+	unsigned int id_crc_errors;	/* crc error in id address mark */
+	unsigned int data_am_errors;	/* data address mark not found */
+	unsigned int data_crc_errors;	/* crc error in data field */
+	unsigned int overrun_errors;	/* fdc access timing problem */
+	unsigned int no_data_errors;	/* sector not found */
+	unsigned int retries;	/* number of tape retries */
+	/* ecc statistics */
+	unsigned int crc_errors;	/* crc error in data */
+	unsigned int crc_failures;	/* bad data without crc error */
+	unsigned int ecc_failures;	/* failed to correct */
+	unsigned int corrected;	/* total sectors corrected */
+	/* general statistics */
+	unsigned int rewinds;	/* number of tape rewinds */
+	unsigned int defects;	/* bad sectors due to media defects */
+} history_record;
+
+/* this structure contains * ALL * information that we want
+ * our child modules to know about, but don't want them to
+ * modify. 
+ */
+typedef struct {
+	/*  vendor information */
+	vendor_struct fti_drive_type;
+	/*  data rates */
+	unsigned int fti_used_data_rate;
+	unsigned int fti_drive_max_rate;
+	unsigned int fti_fdc_max_rate;
+	/*  drive selection, either FTAPE_SEL_A/B/C/D */
+	int fti_drive_sel;      
+	/*  flags set after decode the drive and tape status   */
+	unsigned int fti_formatted      :1;
+	unsigned int fti_no_tape        :1;
+	unsigned int fti_write_protected:1;
+	unsigned int fti_new_tape       :1;
+	/*  values of last queried drive/tape status and error */
+	ft_drive_error  fti_last_error;
+	ft_drive_status fti_last_status;
+	/*  cartridge geometry */
+	unsigned int fti_tracks_per_tape;
+	unsigned int fti_segments_per_track;
+	/*  location of header segments, etc. */
+	int fti_used_header_segment;
+	int fti_header_segment_1;
+	int fti_header_segment_2;
+	int fti_first_data_segment;
+	int fti_last_data_segment;
+	/*  the format code as stored in the header segment  */
+	ft_format_type  fti_format_code;
+	/*  the following is the sole reason for the ftape_set_status() call */
+	unsigned int fti_qic_std;
+	/*  is tape running? */
+	volatile enum runner_status_enum fti_runner_status;
+	/*  is tape reading/writing/verifying/formatting/deleting */
+	buffer_state_enum fti_state;
+	/*  flags fatal hardware error */
+	unsigned int fti_failure:1;
+	/*  history record */
+	history_record fti_history;
+} ftape_info;
+
+/* vendor information */
+#define ft_drive_type          ftape_status.fti_drive_type
+/*  data rates */
+#define ft_data_rate           ftape_status.fti_used_data_rate
+#define ft_drive_max_rate      ftape_status.fti_drive_max_rate
+#define ft_fdc_max_rate        ftape_status.fti_fdc_max_rate
+/*  drive selection, either FTAPE_SEL_A/B/C/D */
+#define ft_drive_sel           ftape_status.fti_drive_sel
+/*  flags set after decode the drive and tape status   */
+#define ft_formatted           ftape_status.fti_formatted
+#define ft_no_tape             ftape_status.fti_no_tape
+#define ft_write_protected     ftape_status.fti_write_protected
+#define ft_new_tape            ftape_status.fti_new_tape
+/*  values of last queried drive/tape status and error */
+#define ft_last_error          ftape_status.fti_last_error
+#define ft_last_status         ftape_status.fti_last_status
+/*  cartridge geometry */
+#define ft_tracks_per_tape     ftape_status.fti_tracks_per_tape
+#define ft_segments_per_track  ftape_status.fti_segments_per_track
+/*  the format code as stored in the header segment  */
+#define ft_format_code         ftape_status.fti_format_code
+/*  the qic status as returned by report drive configuration */
+#define ft_qic_std             ftape_status.fti_qic_std
+#define ft_used_header_segment ftape_status.fti_used_header_segment
+#define ft_header_segment_1    ftape_status.fti_header_segment_1
+#define ft_header_segment_2    ftape_status.fti_header_segment_2
+#define ft_first_data_segment  ftape_status.fti_first_data_segment
+#define ft_last_data_segment   ftape_status.fti_last_data_segment
+/*  is tape running? */
+#define ft_runner_status       ftape_status.fti_runner_status
+/*  is tape reading/writing/verifying/formatting/deleting */
+#define ft_driver_state        ftape_status.fti_state
+/*  flags fatal hardware error */
+#define ft_failure             ftape_status.fti_failure
+/*  history record */
+#define ft_history             ftape_status.fti_history
+
+/*
+ *      ftape-ctl.c defined global vars.
+ */
+extern ftape_info ftape_status;
+extern int ftape_segments_per_head;
+extern int ftape_segments_per_cylinder;
+extern int ftape_init_drive_needed;
+
+/*
+ *      ftape-ctl.c defined global functions.
+ */
+extern int  ftape_mmap(struct vm_area_struct *vma);
+extern int  ftape_enable(int drive_selection);
+extern void ftape_disable(void);
+extern int  ftape_seek_to_bot(void);
+extern int  ftape_seek_to_eot(void);
+extern int  ftape_abort_operation(void);
+extern void ftape_calc_timeouts(unsigned int qic_std,
+				 unsigned int data_rate,
+				 unsigned int tape_len);
+extern int  ftape_calibrate_data_rate(unsigned int qic_std);
+extern const ftape_info *ftape_get_status(void);
+#endif
diff --git a/drivers/char/ftape/lowlevel/ftape-ecc.c b/drivers/char/ftape/lowlevel/ftape-ecc.c
new file mode 100644
index 0000000..e5632f6
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-ecc.c
@@ -0,0 +1,853 @@
+/*
+ *
+ *      Copyright (c) 1993 Ning and David Mosberger.
+ 
+ This is based on code originally written by Bas Laarhoven (bas@vimec.nl)
+ and David L. Brown, Jr., and incorporates improvements suggested by
+ Kai Harrekilde-Petersen.
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2, or (at
+ your option) any later version.
+ 
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+ 
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-ecc.c,v $
+ * $Revision: 1.3 $
+ * $Date: 1997/10/05 19:18:10 $
+ *
+ *      This file contains the Reed-Solomon error correction code 
+ *      for the QIC-40/80 floppy-tape driver for Linux.
+ */
+
+#include <linux/ftape.h>
+
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-ecc.h"
+
+/* Machines that are big-endian should define macro BIG_ENDIAN.
+ * Unfortunately, there doesn't appear to be a standard include file
+ * that works for all OSs.
+ */
+
+#if defined(__sparc__) || defined(__hppa)
+#define BIG_ENDIAN
+#endif				/* __sparc__ || __hppa */
+
+#if defined(__mips__)
+#error Find a smart way to determine the Endianness of the MIPS CPU
+#endif
+
+/* Notice: to minimize the potential for confusion, we use r to
+ *         denote the independent variable of the polynomials in the
+ *         Galois Field GF(2^8).  We reserve x for polynomials that
+ *         that have coefficients in GF(2^8).
+ *         
+ * The Galois Field in which coefficient arithmetic is performed are
+ * the polynomials over Z_2 (i.e., 0 and 1) modulo the irreducible
+ * polynomial f(r), where f(r)=r^8 + r^7 + r^2 + r + 1.  A polynomial
+ * is represented as a byte with the MSB as the coefficient of r^7 and
+ * the LSB as the coefficient of r^0.  For example, the binary
+ * representation of f(x) is 0x187 (of course, this doesn't fit into 8
+ * bits).  In this field, the polynomial r is a primitive element.
+ * That is, r^i with i in 0,...,255 enumerates all elements in the
+ * field.
+ *
+ * The generator polynomial for the QIC-80 ECC is
+ *
+ *      g(x) = x^3 + r^105*x^2 + r^105*x + 1
+ *
+ * which can be factored into:
+ *
+ *      g(x) = (x-r^-1)(x-r^0)(x-r^1)
+ *
+ * the byte representation of the coefficients are:
+ *
+ *      r^105 = 0xc0
+ *      r^-1  = 0xc3
+ *      r^0   = 0x01
+ *      r^1   = 0x02
+ *
+ * Notice that r^-1 = r^254 as exponent arithmetic is performed
+ * modulo 2^8-1 = 255.
+ *
+ * For more information on Galois Fields and Reed-Solomon codes, refer
+ * to any good book.  I found _An Introduction to Error Correcting
+ * Codes with Applications_ by S. A. Vanstone and P. C. van Oorschot
+ * to be a good introduction into the former.  _CODING THEORY: The
+ * Essentials_ I found very useful for its concise description of
+ * Reed-Solomon encoding/decoding.
+ *
+ */
+
+typedef __u8 Matrix[3][3];
+
+/*
+ * gfpow[] is defined such that gfpow[i] returns r^i if
+ * i is in the range [0..255].
+ */
+static const __u8 gfpow[] =
+{
+	0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80,
+	0x87, 0x89, 0x95, 0xad, 0xdd, 0x3d, 0x7a, 0xf4,
+	0x6f, 0xde, 0x3b, 0x76, 0xec, 0x5f, 0xbe, 0xfb,
+	0x71, 0xe2, 0x43, 0x86, 0x8b, 0x91, 0xa5, 0xcd,
+	0x1d, 0x3a, 0x74, 0xe8, 0x57, 0xae, 0xdb, 0x31,
+	0x62, 0xc4, 0x0f, 0x1e, 0x3c, 0x78, 0xf0, 0x67,
+	0xce, 0x1b, 0x36, 0x6c, 0xd8, 0x37, 0x6e, 0xdc,
+	0x3f, 0x7e, 0xfc, 0x7f, 0xfe, 0x7b, 0xf6, 0x6b,
+	0xd6, 0x2b, 0x56, 0xac, 0xdf, 0x39, 0x72, 0xe4,
+	0x4f, 0x9e, 0xbb, 0xf1, 0x65, 0xca, 0x13, 0x26,
+	0x4c, 0x98, 0xb7, 0xe9, 0x55, 0xaa, 0xd3, 0x21,
+	0x42, 0x84, 0x8f, 0x99, 0xb5, 0xed, 0x5d, 0xba,
+	0xf3, 0x61, 0xc2, 0x03, 0x06, 0x0c, 0x18, 0x30,
+	0x60, 0xc0, 0x07, 0x0e, 0x1c, 0x38, 0x70, 0xe0,
+	0x47, 0x8e, 0x9b, 0xb1, 0xe5, 0x4d, 0x9a, 0xb3,
+	0xe1, 0x45, 0x8a, 0x93, 0xa1, 0xc5, 0x0d, 0x1a,
+	0x34, 0x68, 0xd0, 0x27, 0x4e, 0x9c, 0xbf, 0xf9,
+	0x75, 0xea, 0x53, 0xa6, 0xcb, 0x11, 0x22, 0x44,
+	0x88, 0x97, 0xa9, 0xd5, 0x2d, 0x5a, 0xb4, 0xef,
+	0x59, 0xb2, 0xe3, 0x41, 0x82, 0x83, 0x81, 0x85,
+	0x8d, 0x9d, 0xbd, 0xfd, 0x7d, 0xfa, 0x73, 0xe6,
+	0x4b, 0x96, 0xab, 0xd1, 0x25, 0x4a, 0x94, 0xaf,
+	0xd9, 0x35, 0x6a, 0xd4, 0x2f, 0x5e, 0xbc, 0xff,
+	0x79, 0xf2, 0x63, 0xc6, 0x0b, 0x16, 0x2c, 0x58,
+	0xb0, 0xe7, 0x49, 0x92, 0xa3, 0xc1, 0x05, 0x0a,
+	0x14, 0x28, 0x50, 0xa0, 0xc7, 0x09, 0x12, 0x24,
+	0x48, 0x90, 0xa7, 0xc9, 0x15, 0x2a, 0x54, 0xa8,
+	0xd7, 0x29, 0x52, 0xa4, 0xcf, 0x19, 0x32, 0x64,
+	0xc8, 0x17, 0x2e, 0x5c, 0xb8, 0xf7, 0x69, 0xd2,
+	0x23, 0x46, 0x8c, 0x9f, 0xb9, 0xf5, 0x6d, 0xda,
+	0x33, 0x66, 0xcc, 0x1f, 0x3e, 0x7c, 0xf8, 0x77,
+	0xee, 0x5b, 0xb6, 0xeb, 0x51, 0xa2, 0xc3, 0x01
+};
+
+/*
+ * This is a log table.  That is, gflog[r^i] returns i (modulo f(r)).
+ * gflog[0] is undefined and the first element is therefore not valid.
+ */
+static const __u8 gflog[256] =
+{
+	0xff, 0x00, 0x01, 0x63, 0x02, 0xc6, 0x64, 0x6a,
+	0x03, 0xcd, 0xc7, 0xbc, 0x65, 0x7e, 0x6b, 0x2a,
+	0x04, 0x8d, 0xce, 0x4e, 0xc8, 0xd4, 0xbd, 0xe1,
+	0x66, 0xdd, 0x7f, 0x31, 0x6c, 0x20, 0x2b, 0xf3,
+	0x05, 0x57, 0x8e, 0xe8, 0xcf, 0xac, 0x4f, 0x83,
+	0xc9, 0xd9, 0xd5, 0x41, 0xbe, 0x94, 0xe2, 0xb4,
+	0x67, 0x27, 0xde, 0xf0, 0x80, 0xb1, 0x32, 0x35,
+	0x6d, 0x45, 0x21, 0x12, 0x2c, 0x0d, 0xf4, 0x38,
+	0x06, 0x9b, 0x58, 0x1a, 0x8f, 0x79, 0xe9, 0x70,
+	0xd0, 0xc2, 0xad, 0xa8, 0x50, 0x75, 0x84, 0x48,
+	0xca, 0xfc, 0xda, 0x8a, 0xd6, 0x54, 0x42, 0x24,
+	0xbf, 0x98, 0x95, 0xf9, 0xe3, 0x5e, 0xb5, 0x15,
+	0x68, 0x61, 0x28, 0xba, 0xdf, 0x4c, 0xf1, 0x2f,
+	0x81, 0xe6, 0xb2, 0x3f, 0x33, 0xee, 0x36, 0x10,
+	0x6e, 0x18, 0x46, 0xa6, 0x22, 0x88, 0x13, 0xf7,
+	0x2d, 0xb8, 0x0e, 0x3d, 0xf5, 0xa4, 0x39, 0x3b,
+	0x07, 0x9e, 0x9c, 0x9d, 0x59, 0x9f, 0x1b, 0x08,
+	0x90, 0x09, 0x7a, 0x1c, 0xea, 0xa0, 0x71, 0x5a,
+	0xd1, 0x1d, 0xc3, 0x7b, 0xae, 0x0a, 0xa9, 0x91,
+	0x51, 0x5b, 0x76, 0x72, 0x85, 0xa1, 0x49, 0xeb,
+	0xcb, 0x7c, 0xfd, 0xc4, 0xdb, 0x1e, 0x8b, 0xd2,
+	0xd7, 0x92, 0x55, 0xaa, 0x43, 0x0b, 0x25, 0xaf,
+	0xc0, 0x73, 0x99, 0x77, 0x96, 0x5c, 0xfa, 0x52,
+	0xe4, 0xec, 0x5f, 0x4a, 0xb6, 0xa2, 0x16, 0x86,
+	0x69, 0xc5, 0x62, 0xfe, 0x29, 0x7d, 0xbb, 0xcc,
+	0xe0, 0xd3, 0x4d, 0x8c, 0xf2, 0x1f, 0x30, 0xdc,
+	0x82, 0xab, 0xe7, 0x56, 0xb3, 0x93, 0x40, 0xd8,
+	0x34, 0xb0, 0xef, 0x26, 0x37, 0x0c, 0x11, 0x44,
+	0x6f, 0x78, 0x19, 0x9a, 0x47, 0x74, 0xa7, 0xc1,
+	0x23, 0x53, 0x89, 0xfb, 0x14, 0x5d, 0xf8, 0x97,
+	0x2e, 0x4b, 0xb9, 0x60, 0x0f, 0xed, 0x3e, 0xe5,
+	0xf6, 0x87, 0xa5, 0x17, 0x3a, 0xa3, 0x3c, 0xb7
+};
+
+/* This is a multiplication table for the factor 0xc0 (i.e., r^105 (mod f(r)).
+ * gfmul_c0[f] returns r^105 * f(r) (modulo f(r)).
+ */
+static const __u8 gfmul_c0[256] =
+{
+	0x00, 0xc0, 0x07, 0xc7, 0x0e, 0xce, 0x09, 0xc9,
+	0x1c, 0xdc, 0x1b, 0xdb, 0x12, 0xd2, 0x15, 0xd5,
+	0x38, 0xf8, 0x3f, 0xff, 0x36, 0xf6, 0x31, 0xf1,
+	0x24, 0xe4, 0x23, 0xe3, 0x2a, 0xea, 0x2d, 0xed,
+	0x70, 0xb0, 0x77, 0xb7, 0x7e, 0xbe, 0x79, 0xb9,
+	0x6c, 0xac, 0x6b, 0xab, 0x62, 0xa2, 0x65, 0xa5,
+	0x48, 0x88, 0x4f, 0x8f, 0x46, 0x86, 0x41, 0x81,
+	0x54, 0x94, 0x53, 0x93, 0x5a, 0x9a, 0x5d, 0x9d,
+	0xe0, 0x20, 0xe7, 0x27, 0xee, 0x2e, 0xe9, 0x29,
+	0xfc, 0x3c, 0xfb, 0x3b, 0xf2, 0x32, 0xf5, 0x35,
+	0xd8, 0x18, 0xdf, 0x1f, 0xd6, 0x16, 0xd1, 0x11,
+	0xc4, 0x04, 0xc3, 0x03, 0xca, 0x0a, 0xcd, 0x0d,
+	0x90, 0x50, 0x97, 0x57, 0x9e, 0x5e, 0x99, 0x59,
+	0x8c, 0x4c, 0x8b, 0x4b, 0x82, 0x42, 0x85, 0x45,
+	0xa8, 0x68, 0xaf, 0x6f, 0xa6, 0x66, 0xa1, 0x61,
+	0xb4, 0x74, 0xb3, 0x73, 0xba, 0x7a, 0xbd, 0x7d,
+	0x47, 0x87, 0x40, 0x80, 0x49, 0x89, 0x4e, 0x8e,
+	0x5b, 0x9b, 0x5c, 0x9c, 0x55, 0x95, 0x52, 0x92,
+	0x7f, 0xbf, 0x78, 0xb8, 0x71, 0xb1, 0x76, 0xb6,
+	0x63, 0xa3, 0x64, 0xa4, 0x6d, 0xad, 0x6a, 0xaa,
+	0x37, 0xf7, 0x30, 0xf0, 0x39, 0xf9, 0x3e, 0xfe,
+	0x2b, 0xeb, 0x2c, 0xec, 0x25, 0xe5, 0x22, 0xe2,
+	0x0f, 0xcf, 0x08, 0xc8, 0x01, 0xc1, 0x06, 0xc6,
+	0x13, 0xd3, 0x14, 0xd4, 0x1d, 0xdd, 0x1a, 0xda,
+	0xa7, 0x67, 0xa0, 0x60, 0xa9, 0x69, 0xae, 0x6e,
+	0xbb, 0x7b, 0xbc, 0x7c, 0xb5, 0x75, 0xb2, 0x72,
+	0x9f, 0x5f, 0x98, 0x58, 0x91, 0x51, 0x96, 0x56,
+	0x83, 0x43, 0x84, 0x44, 0x8d, 0x4d, 0x8a, 0x4a,
+	0xd7, 0x17, 0xd0, 0x10, 0xd9, 0x19, 0xde, 0x1e,
+	0xcb, 0x0b, 0xcc, 0x0c, 0xc5, 0x05, 0xc2, 0x02,
+	0xef, 0x2f, 0xe8, 0x28, 0xe1, 0x21, 0xe6, 0x26,
+	0xf3, 0x33, 0xf4, 0x34, 0xfd, 0x3d, 0xfa, 0x3a
+};
+
+
+/* Returns V modulo 255 provided V is in the range -255,-254,...,509.
+ */
+static inline __u8 mod255(int v)
+{
+	if (v > 0) {
+		if (v < 255) {
+			return v;
+		} else {
+			return v - 255;
+		}
+	} else {
+		return v + 255;
+	}
+}
+
+
+/* Add two numbers in the field.  Addition in this field is equivalent
+ * to a bit-wise exclusive OR operation---subtraction is therefore
+ * identical to addition.
+ */
+static inline __u8 gfadd(__u8 a, __u8 b)
+{
+	return a ^ b;
+}
+
+
+/* Add two vectors of numbers in the field.  Each byte in A and B gets
+ * added individually.
+ */
+static inline unsigned long gfadd_long(unsigned long a, unsigned long b)
+{
+	return a ^ b;
+}
+
+
+/* Multiply two numbers in the field:
+ */
+static inline __u8 gfmul(__u8 a, __u8 b)
+{
+	if (a && b) {
+		return gfpow[mod255(gflog[a] + gflog[b])];
+	} else {
+		return 0;
+	}
+}
+
+
+/* Just like gfmul, except we have already looked up the log of the
+ * second number.
+ */
+static inline __u8 gfmul_exp(__u8 a, int b)
+{
+	if (a) {
+		return gfpow[mod255(gflog[a] + b)];
+	} else {
+		return 0;
+	}
+}
+
+
+/* Just like gfmul_exp, except that A is a vector of numbers.  That
+ * is, each byte in A gets multiplied by gfpow[mod255(B)].
+ */
+static inline unsigned long gfmul_exp_long(unsigned long a, int b)
+{
+	__u8 t;
+
+	if (sizeof(long) == 4) {
+		return (
+		((t = (__u32)a >> 24 & 0xff) ?
+		 (((__u32) gfpow[mod255(gflog[t] + b)]) << 24) : 0) |
+		((t = (__u32)a >> 16 & 0xff) ?
+		 (((__u32) gfpow[mod255(gflog[t] + b)]) << 16) : 0) |
+		((t = (__u32)a >> 8 & 0xff) ?
+		 (((__u32) gfpow[mod255(gflog[t] + b)]) << 8) : 0) |
+		((t = (__u32)a >> 0 & 0xff) ?
+		 (((__u32) gfpow[mod255(gflog[t] + b)]) << 0) : 0));
+	} else if (sizeof(long) == 8) {
+		return (
+		((t = (__u64)a >> 56 & 0xff) ?
+		 (((__u64) gfpow[mod255(gflog[t] + b)]) << 56) : 0) |
+		((t = (__u64)a >> 48 & 0xff) ?
+		 (((__u64) gfpow[mod255(gflog[t] + b)]) << 48) : 0) |
+		((t = (__u64)a >> 40 & 0xff) ?
+		 (((__u64) gfpow[mod255(gflog[t] + b)]) << 40) : 0) |
+		((t = (__u64)a >> 32 & 0xff) ?
+		 (((__u64) gfpow[mod255(gflog[t] + b)]) << 32) : 0) |
+		((t = (__u64)a >> 24 & 0xff) ?
+		 (((__u64) gfpow[mod255(gflog[t] + b)]) << 24) : 0) |
+		((t = (__u64)a >> 16 & 0xff) ?
+		 (((__u64) gfpow[mod255(gflog[t] + b)]) << 16) : 0) |
+		((t = (__u64)a >> 8 & 0xff) ?
+		 (((__u64) gfpow[mod255(gflog[t] + b)]) << 8) : 0) |
+		((t = (__u64)a >> 0 & 0xff) ?
+		 (((__u64) gfpow[mod255(gflog[t] + b)]) << 0) : 0));
+	} else {
+		TRACE_FUN(ft_t_any);
+		TRACE_ABORT(-1, ft_t_err, "Error: size of long is %d bytes",
+			    (int)sizeof(long));
+	}
+}
+
+
+/* Divide two numbers in the field.  Returns a/b (modulo f(x)).
+ */
+static inline __u8 gfdiv(__u8 a, __u8 b)
+{
+	if (!b) {
+		TRACE_FUN(ft_t_any);
+		TRACE_ABORT(0xff, ft_t_bug, "Error: division by zero");
+	} else if (a == 0) {
+		return 0;
+	} else {
+		return gfpow[mod255(gflog[a] - gflog[b])];
+	}
+}
+
+
+/* The following functions return the inverse of the matrix of the
+ * linear system that needs to be solved to determine the error
+ * magnitudes.  The first deals with matrices of rank 3, while the
+ * second deals with matrices of rank 2.  The error indices are passed
+ * in arguments L0,..,L2 (0=first sector, 31=last sector).  The error
+ * indices must be sorted in ascending order, i.e., L0<L1<L2.
+ *
+ * The linear system that needs to be solved for the error magnitudes
+ * is A * b = s, where s is the known vector of syndromes, b is the
+ * vector of error magnitudes and A in the ORDER=3 case:
+ *
+ *    A_3 = {{1/r^L[0], 1/r^L[1], 1/r^L[2]},
+ *          {        1,        1,        1},
+ *          { r^L[0], r^L[1], r^L[2]}} 
+ */
+static inline int gfinv3(__u8 l0,
+			 __u8 l1, 
+			 __u8 l2, 
+			 Matrix Ainv)
+{
+	__u8 det;
+	__u8 t20, t10, t21, t12, t01, t02;
+	int log_det;
+
+	/* compute some intermediate results: */
+	t20 = gfpow[l2 - l0];	        /* t20 = r^l2/r^l0 */
+	t10 = gfpow[l1 - l0];	        /* t10 = r^l1/r^l0 */
+	t21 = gfpow[l2 - l1];	        /* t21 = r^l2/r^l1 */
+	t12 = gfpow[l1 - l2 + 255];	/* t12 = r^l1/r^l2 */
+	t01 = gfpow[l0 - l1 + 255];	/* t01 = r^l0/r^l1 */
+	t02 = gfpow[l0 - l2 + 255];	/* t02 = r^l0/r^l2 */
+	/* Calculate the determinant of matrix A_3^-1 (sometimes
+	 * called the Vandermonde determinant):
+	 */
+	det = gfadd(t20, gfadd(t10, gfadd(t21, gfadd(t12, gfadd(t01, t02)))));
+	if (!det) {
+		TRACE_FUN(ft_t_any);
+		TRACE_ABORT(0, ft_t_err,
+			   "Inversion failed (3 CRC errors, >0 CRC failures)");
+	}
+	log_det = 255 - gflog[det];
+
+	/* Now, calculate all of the coefficients:
+	 */
+	Ainv[0][0]= gfmul_exp(gfadd(gfpow[l1], gfpow[l2]), log_det);
+	Ainv[0][1]= gfmul_exp(gfadd(t21, t12), log_det);
+	Ainv[0][2]= gfmul_exp(gfadd(gfpow[255 - l1], gfpow[255 - l2]),log_det);
+
+	Ainv[1][0]= gfmul_exp(gfadd(gfpow[l0], gfpow[l2]), log_det);
+	Ainv[1][1]= gfmul_exp(gfadd(t20, t02), log_det);
+	Ainv[1][2]= gfmul_exp(gfadd(gfpow[255 - l0], gfpow[255 - l2]),log_det);
+
+	Ainv[2][0]= gfmul_exp(gfadd(gfpow[l0], gfpow[l1]), log_det);
+	Ainv[2][1]= gfmul_exp(gfadd(t10, t01), log_det);
+	Ainv[2][2]= gfmul_exp(gfadd(gfpow[255 - l0], gfpow[255 - l1]),log_det);
+
+	return 1;
+}
+
+
+static inline int gfinv2(__u8 l0, __u8 l1, Matrix Ainv)
+{
+	__u8 det;
+	__u8 t1, t2;
+	int log_det;
+
+	t1 = gfpow[255 - l0];
+	t2 = gfpow[255 - l1];
+	det = gfadd(t1, t2);
+	if (!det) {
+		TRACE_FUN(ft_t_any);
+		TRACE_ABORT(0, ft_t_err,
+			   "Inversion failed (2 CRC errors, >0 CRC failures)");
+	}
+	log_det = 255 - gflog[det];
+
+	/* Now, calculate all of the coefficients:
+	 */
+	Ainv[0][0] = Ainv[1][0] = gfpow[log_det];
+
+	Ainv[0][1] = gfmul_exp(t2, log_det);
+	Ainv[1][1] = gfmul_exp(t1, log_det);
+
+	return 1;
+}
+
+
+/* Multiply matrix A by vector S and return result in vector B.  M is
+ * assumed to be of order NxN, S and B of order Nx1.
+ */
+static inline void gfmat_mul(int n, Matrix A, 
+			     __u8 *s, __u8 *b)
+{
+	int i, j;
+	__u8 dot_prod;
+
+	for (i = 0; i < n; ++i) {
+		dot_prod = 0;
+		for (j = 0; j < n; ++j) {
+			dot_prod = gfadd(dot_prod, gfmul(A[i][j], s[j]));
+		}
+		b[i] = dot_prod;
+	}
+}
+
+
+
+/* The Reed Solomon ECC codes are computed over the N-th byte of each
+ * block, where N=SECTOR_SIZE.  There are up to 29 blocks of data, and
+ * 3 blocks of ECC.  The blocks are stored contiguously in memory.  A
+ * segment, consequently, is assumed to have at least 4 blocks: one or
+ * more data blocks plus three ECC blocks.
+ *
+ * Notice: In QIC-80 speak, a CRC error is a sector with an incorrect
+ *         CRC.  A CRC failure is a sector with incorrect data, but
+ *         a valid CRC.  In the error control literature, the former
+ *         is usually called "erasure", the latter "error."
+ */
+/* Compute the parity bytes for C columns of data, where C is the
+ * number of bytes that fit into a long integer.  We use a linear
+ * feed-back register to do this.  The parity bytes P[0], P[STRIDE],
+ * P[2*STRIDE] are computed such that:
+ *
+ *              x^k * p(x) + m(x) = 0 (modulo g(x))
+ *
+ * where k = NBLOCKS,
+ *       p(x) = P[0] + P[STRIDE]*x + P[2*STRIDE]*x^2, and
+ *       m(x) = sum_{i=0}^k m_i*x^i.
+ *       m_i = DATA[i*SECTOR_SIZE]
+ */
+static inline void set_parity(unsigned long *data,
+			      int nblocks, 
+			      unsigned long *p, 
+			      int stride)
+{
+	unsigned long p0, p1, p2, t1, t2, *end;
+
+	end = data + nblocks * (FT_SECTOR_SIZE / sizeof(long));
+	p0 = p1 = p2 = 0;
+	while (data < end) {
+		/* The new parity bytes p0_i, p1_i, p2_i are computed
+		 * from the old values p0_{i-1}, p1_{i-1}, p2_{i-1}
+		 * recursively as:
+		 *
+		 *        p0_i = p1_{i-1} + r^105 * (m_{i-1} - p0_{i-1})
+		 *        p1_i = p2_{i-1} + r^105 * (m_{i-1} - p0_{i-1})
+		 *        p2_i =                    (m_{i-1} - p0_{i-1})
+		 *
+		 * With the initial condition: p0_0 = p1_0 = p2_0 = 0.
+		 */
+		t1 = gfadd_long(*data, p0);
+		/*
+		 * Multiply each byte in t1 by 0xc0:
+		 */
+		if (sizeof(long) == 4) {
+			t2= (((__u32) gfmul_c0[(__u32)t1 >> 24 & 0xff]) << 24 |
+			     ((__u32) gfmul_c0[(__u32)t1 >> 16 & 0xff]) << 16 |
+			     ((__u32) gfmul_c0[(__u32)t1 >>  8 & 0xff]) <<  8 |
+			     ((__u32) gfmul_c0[(__u32)t1 >>  0 & 0xff]) <<  0);
+		} else if (sizeof(long) == 8) {
+			t2= (((__u64) gfmul_c0[(__u64)t1 >> 56 & 0xff]) << 56 |
+			     ((__u64) gfmul_c0[(__u64)t1 >> 48 & 0xff]) << 48 |
+			     ((__u64) gfmul_c0[(__u64)t1 >> 40 & 0xff]) << 40 |
+			     ((__u64) gfmul_c0[(__u64)t1 >> 32 & 0xff]) << 32 |
+			     ((__u64) gfmul_c0[(__u64)t1 >> 24 & 0xff]) << 24 |
+			     ((__u64) gfmul_c0[(__u64)t1 >> 16 & 0xff]) << 16 |
+			     ((__u64) gfmul_c0[(__u64)t1 >>  8 & 0xff]) <<  8 |
+			     ((__u64) gfmul_c0[(__u64)t1 >>  0 & 0xff]) <<  0);
+		} else {
+			TRACE_FUN(ft_t_any);
+			TRACE(ft_t_err, "Error: long is of size %d",
+			      (int) sizeof(long));
+			TRACE_EXIT;
+		}
+		p0 = gfadd_long(t2, p1);
+		p1 = gfadd_long(t2, p2);
+		p2 = t1;
+		data += FT_SECTOR_SIZE / sizeof(long);
+	}
+	*p = p0;
+	p += stride;
+	*p = p1;
+	p += stride;
+	*p = p2;
+	return;
+}
+
+
+/* Compute the 3 syndrome values.  DATA should point to the first byte
+ * of the column for which the syndromes are desired.  The syndromes
+ * are computed over the first NBLOCKS of rows.  The three bytes will
+ * be placed in S[0], S[1], and S[2].
+ *
+ * S[i] is the value of the "message" polynomial m(x) evaluated at the
+ * i-th root of the generator polynomial g(x).
+ *
+ * As g(x)=(x-r^-1)(x-1)(x-r^1) we evaluate the message polynomial at
+ * x=r^-1 to get S[0], at x=r^0=1 to get S[1], and at x=r to get S[2].
+ * This could be done directly and efficiently via the Horner scheme.
+ * However, it would require multiplication tables for the factors
+ * r^-1 (0xc3) and r (0x02).  The following scheme does not require
+ * any multiplication tables beyond what's needed for set_parity()
+ * anyway and is slightly faster if there are no errors and slightly
+ * slower if there are errors.  The latter is hopefully the infrequent
+ * case.
+ *
+ * To understand the alternative algorithm, notice that set_parity(m,
+ * k, p) computes parity bytes such that:
+ *
+ *      x^k * p(x) = m(x) (modulo g(x)).
+ *
+ * That is, to evaluate m(r^m), where r^m is a root of g(x), we can
+ * simply evaluate (r^m)^k*p(r^m).  Also, notice that p is 0 if and
+ * only if s is zero.  That is, if all parity bytes are 0, we know
+ * there is no error in the data and consequently there is no need to
+ * compute s(x) at all!  In all other cases, we compute s(x) from p(x)
+ * by evaluating (r^m)^k*p(r^m) for m=-1, m=0, and m=1.  The p(x)
+ * polynomial is evaluated via the Horner scheme.
+ */
+static int compute_syndromes(unsigned long *data, int nblocks, unsigned long *s)
+{
+	unsigned long p[3];
+
+	set_parity(data, nblocks, p, 1);
+	if (p[0] | p[1] | p[2]) {
+		/* Some of the checked columns do not have a zero
+		 * syndrome.  For simplicity, we compute the syndromes
+		 * for all columns that we have computed the
+		 * remainders for.
+		 */
+		s[0] = gfmul_exp_long(
+			gfadd_long(p[0], 
+				   gfmul_exp_long(
+					   gfadd_long(p[1], 
+						      gfmul_exp_long(p[2], -1)),
+					   -1)), 
+			-nblocks);
+		s[1] = gfadd_long(gfadd_long(p[2], p[1]), p[0]);
+		s[2] = gfmul_exp_long(
+			gfadd_long(p[0], 
+				   gfmul_exp_long(
+					   gfadd_long(p[1],
+						      gfmul_exp_long(p[2], 1)),
+					   1)),
+			nblocks);
+		return 0;
+	} else {
+		return 1;
+	}
+}
+
+
+/* Correct the block in the column pointed to by DATA.  There are NBAD
+ * CRC errors and their indices are in BAD_LOC[0], up to
+ * BAD_LOC[NBAD-1].  If NBAD>1, Ainv holds the inverse of the matrix
+ * of the linear system that needs to be solved to determine the error
+ * magnitudes.  S[0], S[1], and S[2] are the syndrome values.  If row
+ * j gets corrected, then bit j will be set in CORRECTION_MAP.
+ */
+static inline int correct_block(__u8 *data, int nblocks,
+				int nbad, int *bad_loc, Matrix Ainv,
+				__u8 *s,
+				SectorMap * correction_map)
+{
+	int ncorrected = 0;
+	int i;
+	__u8 t1, t2;
+	__u8 c0, c1, c2;	/* check bytes */
+	__u8 error_mag[3], log_error_mag;
+	__u8 *dp, l, e;
+	TRACE_FUN(ft_t_any);
+
+	switch (nbad) {
+	case 0:
+		/* might have a CRC failure: */
+		if (s[0] == 0) {
+			/* more than one error */
+			TRACE_ABORT(-1, ft_t_err,
+				 "ECC failed (0 CRC errors, >1 CRC failures)");
+		}
+		t1 = gfdiv(s[1], s[0]);
+		if ((bad_loc[nbad++] = gflog[t1]) >= nblocks) {
+			TRACE(ft_t_err,
+			      "ECC failed (0 CRC errors, >1 CRC failures)");
+			TRACE_ABORT(-1, ft_t_err,
+				  "attempt to correct data at %d", bad_loc[0]);
+		}
+		error_mag[0] = s[1];
+		break;
+	case 1:
+		t1 = gfadd(gfmul_exp(s[1], bad_loc[0]), s[2]);
+		t2 = gfadd(gfmul_exp(s[0], bad_loc[0]), s[1]);
+		if (t1 == 0 && t2 == 0) {
+			/* one erasure, no error: */
+			Ainv[0][0] = gfpow[bad_loc[0]];
+		} else if (t1 == 0 || t2 == 0) {
+			/* one erasure and more than one error: */
+			TRACE_ABORT(-1, ft_t_err,
+				    "ECC failed (1 erasure, >1 error)");
+		} else {
+			/* one erasure, one error: */
+			if ((bad_loc[nbad++] = gflog[gfdiv(t1, t2)]) 
+			    >= nblocks) {
+				TRACE(ft_t_err, "ECC failed "
+				      "(1 CRC errors, >1 CRC failures)");
+				TRACE_ABORT(-1, ft_t_err,
+					    "attempt to correct data at %d",
+					    bad_loc[1]);
+			}
+			if (!gfinv2(bad_loc[0], bad_loc[1], Ainv)) {
+				/* inversion failed---must have more
+                                 *  than one error 
+				 */
+				TRACE_EXIT -1;
+			}
+		}
+		/* FALL THROUGH TO ERROR MAGNITUDE COMPUTATION:
+		 */
+	case 2:
+	case 3:
+		/* compute error magnitudes: */
+		gfmat_mul(nbad, Ainv, s, error_mag);
+		break;
+
+	default:
+		TRACE_ABORT(-1, ft_t_err,
+			    "Internal Error: number of CRC errors > 3");
+	}
+
+	/* Perform correction by adding ERROR_MAG[i] to the byte at
+	 * offset BAD_LOC[i].  Also add the value of the computed
+	 * error polynomial to the syndrome values.  If the correction
+	 * was successful, the resulting check bytes should be zero
+	 * (i.e., the corrected data is a valid code word).
+	 */
+	c0 = s[0];
+	c1 = s[1];
+	c2 = s[2];
+	for (i = 0; i < nbad; ++i) {
+		e = error_mag[i];
+		if (e) {
+			/* correct the byte at offset L by magnitude E: */
+			l = bad_loc[i];
+			dp = &data[l * FT_SECTOR_SIZE];
+			*dp = gfadd(*dp, e);
+			*correction_map |= 1 << l;
+			++ncorrected;
+
+			log_error_mag = gflog[e];
+			c0 = gfadd(c0, gfpow[mod255(log_error_mag - l)]);
+			c1 = gfadd(c1, e);
+			c2 = gfadd(c2, gfpow[mod255(log_error_mag + l)]);
+		}
+	}
+	if (c0 || c1 || c2) {
+		TRACE_ABORT(-1, ft_t_err,
+			    "ECC self-check failed, too many errors");
+	}
+	TRACE_EXIT ncorrected;
+}
+
+
+#if defined(ECC_SANITY_CHECK) || defined(ECC_PARANOID)
+
+/* Perform a sanity check on the computed parity bytes:
+ */
+static int sanity_check(unsigned long *data, int nblocks)
+{
+	TRACE_FUN(ft_t_any);
+	unsigned long s[3];
+
+	if (!compute_syndromes(data, nblocks, s)) {
+		TRACE_ABORT(0, ft_bug,
+			    "Internal Error: syndrome self-check failed");
+	}
+	TRACE_EXIT 1;
+}
+
+#endif /* defined(ECC_SANITY_CHECK) || defined(ECC_PARANOID) */
+
+/* Compute the parity for an entire segment of data.
+ */
+int ftape_ecc_set_segment_parity(struct memory_segment *mseg)
+{
+	int i;
+	__u8 *parity_bytes;
+
+	parity_bytes = &mseg->data[(mseg->blocks - 3) * FT_SECTOR_SIZE];
+	for (i = 0; i < FT_SECTOR_SIZE; i += sizeof(long)) {
+		set_parity((unsigned long *) &mseg->data[i], mseg->blocks - 3,
+			   (unsigned long *) &parity_bytes[i],
+			   FT_SECTOR_SIZE / sizeof(long));
+#ifdef ECC_PARANOID
+		if (!sanity_check((unsigned long *) &mseg->data[i],
+				   mseg->blocks)) {
+			return -1;
+		}
+#endif				/* ECC_PARANOID */
+	}
+	return 0;
+}
+
+
+/* Checks and corrects (if possible) the segment MSEG.  Returns one of
+ * ECC_OK, ECC_CORRECTED, and ECC_FAILED.
+ */
+int ftape_ecc_correct_data(struct memory_segment *mseg)
+{
+	int col, i, result;
+	int ncorrected = 0;
+	int nerasures = 0;	/* # of erasures (CRC errors) */
+	int erasure_loc[3];	/* erasure locations */
+	unsigned long ss[3];
+	__u8 s[3];
+	Matrix Ainv;
+	TRACE_FUN(ft_t_flow);
+
+	mseg->corrected = 0;
+
+	/* find first column that has non-zero syndromes: */
+	for (col = 0; col < FT_SECTOR_SIZE; col += sizeof(long)) {
+		if (!compute_syndromes((unsigned long *) &mseg->data[col],
+				       mseg->blocks, ss)) {
+			/* something is wrong---have to fix things */
+			break;
+		}
+	}
+	if (col >= FT_SECTOR_SIZE) {
+		/* all syndromes are ok, therefore nothing to correct */
+		TRACE_EXIT ECC_OK;
+	}
+	/* count the number of CRC errors if there were any: */
+	if (mseg->read_bad) {
+		for (i = 0; i < mseg->blocks; i++) {
+			if (BAD_CHECK(mseg->read_bad, i)) {
+				if (nerasures >= 3) {
+					/* this is too much for ECC */
+					TRACE_ABORT(ECC_FAILED, ft_t_err,
+						"ECC failed (>3 CRC errors)");
+				}	/* if */
+				erasure_loc[nerasures++] = i;
+			}
+		}
+	}
+	/*
+	 * If there are at least 2 CRC errors, determine inverse of matrix
+	 * of linear system to be solved:
+	 */
+	switch (nerasures) {
+	case 2:
+		if (!gfinv2(erasure_loc[0], erasure_loc[1], Ainv)) {
+			TRACE_EXIT ECC_FAILED;
+		}
+		break;
+	case 3:
+		if (!gfinv3(erasure_loc[0], erasure_loc[1],
+			    erasure_loc[2], Ainv)) {
+			TRACE_EXIT ECC_FAILED;
+		}
+		break;
+	default:
+		/* this is not an error condition... */
+		break;
+	}
+
+	do {
+		for (i = 0; i < sizeof(long); ++i) {
+			s[0] = ss[0];
+			s[1] = ss[1];
+			s[2] = ss[2];
+			if (s[0] | s[1] | s[2]) {
+#ifdef BIG_ENDIAN
+				result = correct_block(
+					&mseg->data[col + sizeof(long) - 1 - i],
+					mseg->blocks,
+					nerasures,
+					erasure_loc,
+					Ainv,
+					s,
+					&mseg->corrected);
+#else
+				result = correct_block(&mseg->data[col + i],
+						       mseg->blocks,
+						       nerasures,
+						       erasure_loc,
+						       Ainv,
+						       s,
+						       &mseg->corrected);
+#endif
+				if (result < 0) {
+					TRACE_EXIT ECC_FAILED;
+				}
+				ncorrected += result;
+			}
+			ss[0] >>= 8;
+			ss[1] >>= 8;
+			ss[2] >>= 8;
+		}
+
+#ifdef ECC_SANITY_CHECK
+		if (!sanity_check((unsigned long *) &mseg->data[col],
+				  mseg->blocks)) {
+			TRACE_EXIT ECC_FAILED;
+		}
+#endif				/* ECC_SANITY_CHECK */
+
+		/* find next column with non-zero syndromes: */
+		while ((col += sizeof(long)) < FT_SECTOR_SIZE) {
+			if (!compute_syndromes((unsigned long *)
+				    &mseg->data[col], mseg->blocks, ss)) {
+				/* something is wrong---have to fix things */
+				break;
+			}
+		}
+	} while (col < FT_SECTOR_SIZE);
+	if (ncorrected && nerasures == 0) {
+		TRACE(ft_t_warn, "block contained error not caught by CRC");
+	}
+	TRACE((ncorrected > 0) ? ft_t_noise : ft_t_any, "number of corrections: %d", ncorrected);
+	TRACE_EXIT ncorrected ? ECC_CORRECTED : ECC_OK;
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-ecc.h b/drivers/char/ftape/lowlevel/ftape-ecc.h
new file mode 100644
index 0000000..4829146
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-ecc.h
@@ -0,0 +1,84 @@
+#ifndef _FTAPE_ECC_H_
+#define _FTAPE_ECC_H_
+
+/*
+ *      Copyright (C) 1993 Ning and David Mosberger.
+ *      Original:
+ *      Copyright (C) 1993 Bas Laarhoven.
+ *      Copyright (C) 1992 David L. Brown, Jr.
+ 
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2, or (at
+ your option) any later version.
+ 
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+ 
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ USA.
+ 
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-ecc.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:11 $
+ *
+ *      This file contains the definitions for the
+ *      Reed-Solomon error correction code 
+ *      for the QIC-40/80 tape streamer device driver.
+ */
+
+#include "../lowlevel/ftape-bsm.h"
+
+#define BAD_CLEAR(entry) ((entry)=0)
+#define BAD_SET(entry,sector) ((entry)|=(1<<(sector)))
+#define BAD_CHECK(entry,sector) ((entry)&(1<<(sector)))
+
+/*
+ * Return values for ecc_correct_data:
+ */
+enum {
+	ECC_OK,			/* Data was correct. */
+	ECC_CORRECTED,		/* Correctable error in data. */
+	ECC_FAILED,		/* Could not correct data. */
+};
+
+/*
+ * Representation of an in memory segment.  MARKED_BAD lists the
+ * sectors that were marked bad during formatting.  If the N-th sector
+ * in a segment is marked bad, bit 1<<N will be set in MARKED_BAD.
+ * The sectors should be read in from the disk and packed, as if the
+ * bad sectors were not there, and the segment just contained fewer
+ * sectors.  READ_SECTORS is a bitmap of errors encountered while
+ * reading the data.  These offsets are relative to the packed data.
+ * BLOCKS is a count of the sectors not marked bad.  This is just to
+ * prevent having to count the zero bits in MARKED_BAD each time this
+ * is needed.  DATA is the actual sector packed data from (or to) the
+ * tape.
+ */
+ struct memory_segment {
+	SectorMap marked_bad;
+	SectorMap read_bad;
+ 	int blocks;
+ 	__u8 *data;
+	SectorMap corrected;
+ };
+
+/*
+ * ecc.c defined global variables:
+ */
+#ifdef TEST
+extern int ftape_ecc_tracing;
+#endif
+
+/*
+ * ecc.c defined global functions:
+ */
+extern int ftape_ecc_correct_data(struct memory_segment *data);
+extern int ftape_ecc_set_segment_parity(struct memory_segment *data);
+
+#endif	/* _FTAPE_ECC_H_ */
diff --git a/drivers/char/ftape/lowlevel/ftape-format.c b/drivers/char/ftape/lowlevel/ftape-format.c
new file mode 100644
index 0000000..5dd4c59
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-format.c
@@ -0,0 +1,344 @@
+/*
+ * Copyright (C) 1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-format.c,v $
+ * $Revision: 1.2.4.1 $
+ * $Date: 1997/11/14 16:05:39 $
+ *
+ *      This file contains the code to support formatting of floppy
+ *      tape cartridges with the QIC-40/80/3010/3020 floppy-tape
+ *      driver "ftape" for Linux.
+ */
+ 
+#include <linux/string.h>
+#include <linux/errno.h>
+
+#include <linux/ftape.h>
+#include <linux/qic117.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-ecc.h"
+#include "../lowlevel/ftape-bsm.h"
+#include "../lowlevel/ftape-format.h"
+
+#if defined(TESTING)
+#define FT_FMT_SEGS_PER_BUF 50
+#else
+#define FT_FMT_SEGS_PER_BUF (FT_BUFF_SIZE/(4*FT_SECTORS_PER_SEGMENT))
+#endif
+
+static spinlock_t ftape_format_lock;
+
+/*
+ *  first segment of the new buffer
+ */
+static int switch_segment;
+
+/*
+ *  at most 256 segments fit into one 32 kb buffer.  Even TR-1 cartridges have
+ *  more than this many segments per track, so better be careful.
+ *
+ *  buffer_struct *buff: buffer to store the formatting coordinates in
+ *  int  start: starting segment for this buffer.
+ *  int    spt: segments per track
+ *
+ *  Note: segment ids are relative to the start of the track here.
+ */
+static void setup_format_buffer(buffer_struct *buff, int start, int spt,
+				__u8 gap3)
+{
+	int to_do = spt - start;
+	TRACE_FUN(ft_t_flow);
+
+	if (to_do > FT_FMT_SEGS_PER_BUF) {
+		to_do = FT_FMT_SEGS_PER_BUF;
+	}
+	buff->ptr          = buff->address;
+	buff->remaining    = to_do * FT_SECTORS_PER_SEGMENT; /* # sectors */
+	buff->bytes        = buff->remaining * 4; /* need 4 bytes per sector */
+	buff->gap3         = gap3;
+	buff->segment_id   = start;
+	buff->next_segment = start + to_do;
+	if (buff->next_segment >= spt) {
+		buff->next_segment = 0; /* 0 means: stop runner */
+	}
+	buff->status       = waiting; /* tells the isr that it can use
+				       * this buffer
+				       */
+	TRACE_EXIT;
+}
+
+
+/*
+ *  start formatting a new track.
+ */
+int ftape_format_track(const unsigned int track, const __u8 gap3)
+{
+	unsigned long flags;
+	buffer_struct *tail, *head;
+	int status;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE_CATCH(ftape_ready_wait(ftape_timeout.pause, &status),);
+	if (track & 1) {
+		if (!(status & QIC_STATUS_AT_EOT)) {
+			TRACE_CATCH(ftape_seek_to_eot(),);
+		}
+	} else {
+		if (!(status & QIC_STATUS_AT_BOT)) {
+			TRACE_CATCH(ftape_seek_to_bot(),);
+		}
+	}
+	ftape_abort_operation(); /* this sets ft_head = ft_tail = 0 */
+	ftape_set_state(formatting);
+
+	TRACE(ft_t_noise,
+	      "Formatting track %d, logical: from segment %d to %d",
+	      track, track * ft_segments_per_track, 
+	      (track + 1) * ft_segments_per_track - 1);
+	
+	/*
+	 *  initialize the buffer switching protocol for this track
+	 */
+	head = ftape_get_buffer(ft_queue_head); /* tape isn't running yet */
+	tail = ftape_get_buffer(ft_queue_tail); /* tape isn't running yet */
+	switch_segment = 0;
+	do {
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		setup_format_buffer(tail, switch_segment,
+				    ft_segments_per_track, gap3);
+		switch_segment = tail->next_segment;
+	} while ((switch_segment != 0) &&
+		 ((tail = ftape_next_buffer(ft_queue_tail)) != head));
+	/* go */
+	head->status = formatting;
+	TRACE_CATCH(ftape_seek_head_to_track(track),);
+	TRACE_CATCH(ftape_command(QIC_LOGICAL_FORWARD),);
+	spin_lock_irqsave(&ftape_format_lock, flags);
+	TRACE_CATCH(fdc_setup_formatting(head), restore_flags(flags));
+	spin_unlock_irqrestore(&ftape_format_lock, flags);
+	TRACE_EXIT 0;
+}
+
+/*   return segment id of segment currently being formatted and do the
+ *   buffer switching stuff.
+ */
+int ftape_format_status(unsigned int *segment_id)
+{
+	buffer_struct *tail = ftape_get_buffer(ft_queue_tail);
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	while (switch_segment != 0 &&
+	       ftape_get_buffer(ft_queue_head) != tail) {
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		/*  need more buffers, first wait for empty buffer
+		 */
+		TRACE_CATCH(ftape_wait_segment(formatting),);
+		/*  don't worry for gap3. If we ever hit this piece of code,
+		 *  then all buffer already have the correct gap3 set!
+		 */
+		setup_format_buffer(tail, switch_segment,
+				    ft_segments_per_track, tail->gap3);
+		switch_segment = tail->next_segment;
+		if (switch_segment != 0) {
+			tail = ftape_next_buffer(ft_queue_tail);
+		}
+	}
+	/*    should runner stop ?
+	 */
+	if (ft_runner_status == aborting || ft_runner_status == do_abort) {
+		buffer_struct *head = ftape_get_buffer(ft_queue_head);
+		TRACE(ft_t_warn, "Error formatting segment %d",
+		      ftape_get_buffer(ft_queue_head)->segment_id);
+		(void)ftape_abort_operation();
+		TRACE_EXIT (head->status != error) ? -EAGAIN : -EIO;
+	}
+	/*
+	 *  don't care if the timer expires, this is just kind of a
+	 *  "select" operation that lets the calling process sleep
+	 *  until something has happened
+	 */
+	if (fdc_interrupt_wait(5 * FT_SECOND) < 0) {
+		TRACE(ft_t_noise, "End of track %d at segment %d",
+		      ft_location.track,
+		      ftape_get_buffer(ft_queue_head)->segment_id);
+		result = 1;  /* end of track, unlock module */
+	} else {
+		result = 0;
+	}
+	/*
+	 *  the calling process should use the seg id to determine
+	 *  which parts of the dma buffers can be safely overwritten
+	 *  with new data.
+	 */
+	*segment_id = ftape_get_buffer(ft_queue_head)->segment_id;
+	/*
+	 *  Internally we start counting segment ids from the start of
+	 *  each track when formatting, but externally we keep them
+	 *  relative to the start of the tape:
+	 */
+	*segment_id += ft_location.track * ft_segments_per_track;
+	TRACE_EXIT result;
+}
+
+/*
+ *  The segment id is relative to the start of the tape
+ */
+int ftape_verify_segment(const unsigned int segment_id, SectorMap *bsm)
+{
+	int result;
+	int verify_done = 0;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_noise, "Verifying segment %d", segment_id);
+
+	if (ft_driver_state != verifying) {
+		TRACE(ft_t_noise, "calling ftape_abort_operation");
+		if (ftape_abort_operation() < 0) {
+			TRACE(ft_t_err, "ftape_abort_operation failed");
+			TRACE_EXIT -EIO;
+		}
+	}
+	*bsm = 0x00000000;
+	ftape_set_state(verifying);
+	for (;;) {
+		buffer_struct *tail;
+		/*
+		 *  Allow escape from this loop on signal
+		 */
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		/*
+		 *  Search all full buffers for the first matching the
+		 *  wanted segment.  Clear other buffers on the fly.
+		 */
+		tail = ftape_get_buffer(ft_queue_tail);
+		while (!verify_done && tail->status == done) {
+			/*
+			 *  Allow escape from this loop on signal !
+			 */
+			FT_SIGNAL_EXIT(_DONT_BLOCK);
+			if (tail->segment_id == segment_id) {
+				/*  If out buffer is already full,
+				 *  return its contents.  
+				 */
+				TRACE(ft_t_flow, "found segment in cache: %d",
+				      segment_id);
+				if ((tail->soft_error_map |
+				     tail->hard_error_map) != 0) {
+					TRACE(ft_t_info,"bsm[%d] = 0x%08lx",
+					      segment_id,
+					      (unsigned long)
+					      (tail->soft_error_map |
+					      tail->hard_error_map));
+					*bsm = (tail->soft_error_map |
+						tail->hard_error_map);
+				}
+				verify_done = 1;
+			} else {
+				TRACE(ft_t_flow,"zapping segment in cache: %d",
+				      tail->segment_id);
+			}
+			tail->status = waiting;
+			tail = ftape_next_buffer(ft_queue_tail);
+		}
+		if (!verify_done && tail->status == verifying) {
+			if (tail->segment_id == segment_id) {
+				switch(ftape_wait_segment(verifying)) {
+				case 0:
+					break;
+				case -EINTR:
+					TRACE_ABORT(-EINTR, ft_t_warn,
+						    "interrupted by "
+						    "non-blockable signal");
+					break;
+				default:
+					ftape_abort_operation();
+					ftape_set_state(verifying);
+					/* be picky */
+					TRACE_ABORT(-EIO, ft_t_warn,
+						    "wait_segment failed");
+				}
+			} else {
+				/*  We're reading the wrong segment,
+				 *  stop runner.
+				 */
+				TRACE(ft_t_noise, "verifying wrong segment");
+				ftape_abort_operation();
+				ftape_set_state(verifying);
+			}
+		}
+		/*    should runner stop ?
+		 */
+		if (ft_runner_status == aborting) {
+			buffer_struct *head = ftape_get_buffer(ft_queue_head);
+			if (head->status == error ||
+			    head->status == verifying) {
+				/* no data or overrun error */
+				head->status = waiting;
+			}
+			TRACE_CATCH(ftape_dumb_stop(),);
+		} else {
+			/*  If just passed last segment on tape: wait
+			 *  for BOT or EOT mark. Sets ft_runner_status to
+			 *  idle if at lEOT and successful 
+			 */
+			TRACE_CATCH(ftape_handle_logical_eot(),);
+		}
+		if (verify_done) {
+			TRACE_EXIT 0;
+		}
+		/*    Now at least one buffer is idle!
+		 *    Restart runner & tape if needed.
+		 */
+		/*  We could optimize the following a little bit. We know that 
+		 *  the bad sector map is empty.
+		 */
+		tail = ftape_get_buffer(ft_queue_tail);
+		if (tail->status == waiting) {
+			buffer_struct *head = ftape_get_buffer(ft_queue_head);
+
+			ftape_setup_new_segment(head, segment_id, -1);
+			ftape_calc_next_cluster(head);
+			if (ft_runner_status == idle) {
+				result = ftape_start_tape(segment_id,
+							  head->sector_offset);
+				switch(result) {
+				case 0:
+					break;
+				case -ETIME:
+				case -EINTR:
+					TRACE_ABORT(result, ft_t_err, "Error: "
+						    "segment %d unreachable",
+						    segment_id);
+					break;
+				default:
+					*bsm = EMPTY_SEGMENT;
+					TRACE_EXIT 0;
+					break;
+				}
+			}
+			head->status = verifying;
+			fdc_setup_read_write(head, FDC_VERIFY);
+		}
+	}
+	/* not reached */
+	TRACE_EXIT -EIO;
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-format.h b/drivers/char/ftape/lowlevel/ftape-format.h
new file mode 100644
index 0000000..f151615
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-format.h
@@ -0,0 +1,37 @@
+#ifndef _FTAPE_FORMAT_H
+#define _FTAPE_FORMAT_H
+
+/*
+ * Copyright (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-format.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:13 $
+ *
+ *      This file contains the low level definitions for the
+ *      formatting support for the QIC-40/80/3010/3020 floppy-tape
+ *      driver "ftape" for Linux.
+ */
+
+#ifdef __KERNEL__
+extern int ftape_format_track(const unsigned int track, const __u8 gap3);
+extern int ftape_format_status(unsigned int *segment_id);
+extern int ftape_verify_segment(const unsigned int segment_id, SectorMap *bsm);
+#endif /* __KERNEL__ */
+
+#endif
diff --git a/drivers/char/ftape/lowlevel/ftape-init.c b/drivers/char/ftape/lowlevel/ftape-init.c
new file mode 100644
index 0000000..b54260d
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-init.c
@@ -0,0 +1,161 @@
+/*
+ *      Copyright (C) 1993-1996 Bas Laarhoven,
+ *                (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ *      This file contains the code that interfaces the kernel
+ *      for the QIC-40/80/3010/3020 floppy-tape driver for Linux.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/major.h>
+
+#include <linux/ftape.h>
+#include <linux/init.h>
+#include <linux/qic117.h>
+#ifdef CONFIG_ZFTAPE
+#include <linux/zftape.h>
+#endif
+
+#include "../lowlevel/ftape-init.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-read.h"
+#include "../lowlevel/ftape-write.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/fdc-io.h"
+#include "../lowlevel/ftape-buffer.h"
+#include "../lowlevel/ftape-proc.h"
+#include "../lowlevel/ftape-tracing.h"
+
+
+#if defined(MODULE) && !defined(CONFIG_FT_NO_TRACE_AT_ALL)
+static int ft_tracing = -1;
+#endif
+
+
+/*  Called by modules package when installing the driver
+ *  or by kernel during the initialization phase
+ */
+static int __init ftape_init(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+#ifdef MODULE
+#ifndef CONFIG_FT_NO_TRACE_AT_ALL
+	if (ft_tracing != -1) {
+		ftape_tracing = ft_tracing;
+	}
+#endif
+	printk(KERN_INFO FTAPE_VERSION "\n");
+        if (TRACE_LEVEL >= ft_t_info) {
+		printk(
+KERN_INFO "(c) 1993-1996 Bas Laarhoven (bas@vimec.nl)\n"
+KERN_INFO "(c) 1995-1996 Kai Harrekilde-Petersen (khp@dolphinics.no)\n"
+KERN_INFO "(c) 1996-1997 Claus-Justus Heine (claus@momo.math.rwth-aachen.de)\n"
+KERN_INFO "QIC-117 driver for QIC-40/80/3010/3020 floppy tape drives\n");
+        }
+#else /* !MODULE */
+	/* print a short no-nonsense boot message */
+	printk(KERN_INFO FTAPE_VERSION "\n");
+#endif /* MODULE */
+	TRACE(ft_t_info, "installing QIC-117 floppy tape hardware drive ... ");
+	TRACE(ft_t_info, "ftape_init @ 0x%p", ftape_init);
+	/*  Allocate the DMA buffers. They are deallocated at cleanup() time.
+	 */
+#ifdef TESTING
+#ifdef MODULE
+	while (ftape_set_nr_buffers(CONFIG_FT_NR_BUFFERS) < 0) {
+		ftape_sleep(FT_SECOND/20);
+		if (signal_pending(current)) {
+			(void)ftape_set_nr_buffers(0);
+			TRACE(ft_t_bug,
+			      "Killed by signal while allocating buffers.");
+			TRACE_ABORT(-EINTR, 
+				    ft_t_bug, "Free up memory and retry");
+		}
+	}
+#else
+	TRACE_CATCH(ftape_set_nr_buffers(CONFIG_FT_NR_BUFFERS),
+		    (void)ftape_set_nr_buffers(0));
+#endif
+#else
+	TRACE_CATCH(ftape_set_nr_buffers(CONFIG_FT_NR_BUFFERS),
+		    (void)ftape_set_nr_buffers(0));
+#endif
+	ft_drive_sel = -1;
+	ft_failure   = 1;         /* inhibit any operation but open */
+	ftape_udelay_calibrate(); /* must be before fdc_wait_calibrate ! */
+	fdc_wait_calibrate();
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_FT_PROC_FS)
+	(void)ftape_proc_init();
+#endif
+#ifdef CONFIG_ZFTAPE
+	(void)zft_init();
+#endif
+	TRACE_EXIT 0;
+}
+
+module_param(ft_fdc_base,       uint, 0);
+MODULE_PARM_DESC(ft_fdc_base,  "Base address of FDC controller.");
+module_param(ft_fdc_irq,        uint, 0);
+MODULE_PARM_DESC(ft_fdc_irq,   "IRQ (interrupt channel) to use.");
+module_param(ft_fdc_dma,        uint, 0);
+MODULE_PARM_DESC(ft_fdc_dma,   "DMA channel to use.");
+module_param(ft_fdc_threshold,  uint, 0);
+MODULE_PARM_DESC(ft_fdc_threshold,  "Threshold of the FDC Fifo.");
+module_param(ft_fdc_rate_limit, uint, 0);
+MODULE_PARM_DESC(ft_fdc_rate_limit, "Maximal data rate for FDC.");
+module_param(ft_probe_fc10,     bool, 0);
+MODULE_PARM_DESC(ft_probe_fc10,
+	    "If non-zero, probe for a Colorado FC-10/FC-20 controller.");
+module_param(ft_mach2,          bool, 0);
+MODULE_PARM_DESC(ft_mach2,
+	    "If non-zero, probe for a Mountain MACH-2 controller.");
+#if defined(MODULE) && !defined(CONFIG_FT_NO_TRACE_AT_ALL)
+module_param(ft_tracing,        int, 0644);
+MODULE_PARM_DESC(ft_tracing,
+	    "Amount of debugging output, 0 <= tracing <= 8, default 3.");
+#endif
+
+MODULE_AUTHOR(
+	"(c) 1993-1996 Bas Laarhoven (bas@vimec.nl), "
+	"(c) 1995-1996 Kai Harrekilde-Petersen (khp@dolphinics.no), "
+	"(c) 1996, 1997 Claus-Justus Heine (claus@momo.math.rwth-aachen.de)");
+MODULE_DESCRIPTION(
+	"QIC-117 driver for QIC-40/80/3010/3020 floppy tape drives.");
+MODULE_LICENSE("GPL");
+
+static void __exit ftape_exit(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_FT_PROC_FS)
+	ftape_proc_destroy();
+#endif
+	(void)ftape_set_nr_buffers(0);
+        printk(KERN_INFO "ftape: unloaded.\n");
+	TRACE_EXIT;
+}
+
+module_init(ftape_init);
+module_exit(ftape_exit);
diff --git a/drivers/char/ftape/lowlevel/ftape-init.h b/drivers/char/ftape/lowlevel/ftape-init.h
new file mode 100644
index 0000000..99a7b8a
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-init.h
@@ -0,0 +1,43 @@
+#ifndef _FTAPE_INIT_H
+#define _FTAPE_INIT_H
+
+/*
+ * Copyright (C) 1993-1996 Bas Laarhoven,
+ *           (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-init.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:16 $
+ *
+ * This file contains the definitions for the interface to 
+ * the Linux kernel for floppy tape driver ftape.
+ *
+ */
+
+#include <linux/linkage.h>
+#include <linux/signal.h>
+
+#define _NEVER_BLOCK    (sigmask(SIGKILL) | sigmask(SIGSTOP))
+#define _DONT_BLOCK     (_NEVER_BLOCK | sigmask(SIGINT))
+#define _DO_BLOCK       (sigmask(SIGPIPE))
+
+#ifndef QIC117_TAPE_MAJOR
+#define QIC117_TAPE_MAJOR 27
+#endif
+
+#endif
diff --git a/drivers/char/ftape/lowlevel/ftape-io.c b/drivers/char/ftape/lowlevel/ftape-io.c
new file mode 100644
index 0000000..259015a
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-io.c
@@ -0,0 +1,992 @@
+/*
+ *      Copyright (C) 1993-1996 Bas Laarhoven,
+ *                (C) 1996      Kai Harrekilde-Petersen,
+ *                (C) 1997      Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-io.c,v $
+ * $Revision: 1.4 $
+ * $Date: 1997/11/11 14:02:36 $
+ *
+ *      This file contains the general control functions for the
+ *      QIC-40/80/3010/3020 floppy-tape driver "ftape" for Linux.
+ */
+
+#include <linux/errno.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <asm/system.h>
+#include <linux/ioctl.h>
+#include <linux/mtio.h>
+#include <linux/delay.h>
+
+#include <linux/ftape.h>
+#include <linux/qic117.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/fdc-io.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-write.h"
+#include "../lowlevel/ftape-read.h"
+#include "../lowlevel/ftape-init.h"
+#include "../lowlevel/ftape-calibr.h"
+
+/*      Global vars.
+ */
+/* NOTE: sectors start numbering at 1, all others at 0 ! */
+ft_timeout_table ftape_timeout;
+unsigned int ftape_tape_len;
+volatile qic117_cmd_t ftape_current_command;
+const struct qic117_command_table qic117_cmds[] = QIC117_COMMANDS;
+int ftape_might_be_off_track;
+
+/*      Local vars.
+ */
+static int diagnostic_mode;
+static unsigned int ftape_udelay_count;
+static unsigned int ftape_udelay_time;
+
+void ftape_udelay(unsigned int usecs)
+{
+	volatile int count = (ftape_udelay_count * usecs +
+                              ftape_udelay_count - 1) / ftape_udelay_time;
+	volatile int i;
+
+	while (count-- > 0) {
+		for (i = 0; i < 20; ++i);
+	}
+}
+
+void ftape_udelay_calibrate(void)
+{
+	ftape_calibrate("ftape_udelay",
+			ftape_udelay, &ftape_udelay_count, &ftape_udelay_time);
+}
+
+/*      Delay (msec) routine.
+ */
+void ftape_sleep(unsigned int time)
+{
+	TRACE_FUN(ft_t_any);
+
+	time *= 1000;   /* msecs -> usecs */
+	if (time < FT_USPT) {
+		/*  Time too small for scheduler, do a busy wait ! */
+		ftape_udelay(time);
+	} else {
+		long timeout;
+		unsigned long flags;
+		unsigned int ticks = (time + FT_USPT - 1) / FT_USPT;
+
+		TRACE(ft_t_any, "%d msec, %d ticks", time/1000, ticks);
+		timeout = ticks;
+		save_flags(flags);
+		sti();
+		msleep_interruptible(jiffies_to_msecs(timeout));
+		/*  Mmm. Isn't current->blocked == 0xffffffff ?
+		 */
+		if (signal_pending(current)) {
+			TRACE(ft_t_err, "awoken by non-blocked signal :-(");
+		}
+		restore_flags(flags);
+	}
+	TRACE_EXIT;
+}
+
+/*  send a command or parameter to the drive
+ *  Generates # of step pulses.
+ */
+static inline int ft_send_to_drive(int arg)
+{
+	/*  Always wait for a command_timeout period to separate
+	 *  individuals commands and/or parameters.
+	 */
+	ftape_sleep(3 * FT_MILLISECOND);
+	/*  Keep cylinder nr within range, step towards home if possible.
+	 */
+	if (ftape_current_cylinder >= arg) {
+		return fdc_seek(ftape_current_cylinder - arg);
+	} else {
+		return fdc_seek(ftape_current_cylinder + arg);
+	}
+}
+
+/* forward */ int ftape_report_raw_drive_status(int *status);
+
+static int ft_check_cmd_restrictions(qic117_cmd_t command)
+{
+	int status = -1;
+	TRACE_FUN(ft_t_any);
+	
+	TRACE(ft_t_flow, "%s", qic117_cmds[command].name);
+	/* A new motion command during an uninterruptible (motion)
+	 *  command requires a ready status before the new command can
+	 *  be issued. Otherwise a new motion command needs to be
+	 *  checked against required status.
+	 */
+	if (qic117_cmds[command].cmd_type == motion &&
+	    qic117_cmds[ftape_current_command].non_intr) {
+		ftape_report_raw_drive_status(&status);
+		if ((status & QIC_STATUS_READY) == 0) {
+			TRACE(ft_t_noise,
+			      "motion cmd (%d) during non-intr cmd (%d)",
+			      command, ftape_current_command);
+			TRACE(ft_t_noise, "waiting until drive gets ready");
+			ftape_ready_wait(ftape_timeout.seek,
+					 &status);
+		}
+	}
+	if (qic117_cmds[command].mask != 0) {
+		__u8 difference;
+		/*  Some commands do require a certain status:
+		 */
+		if (status == -1) {	/* not yet set */
+			ftape_report_raw_drive_status(&status);
+		}
+		difference = ((status ^ qic117_cmds[command].state) &
+			      qic117_cmds[command].mask);
+		/*  Wait until the drive gets
+		 *  ready. This may last forever if
+		 *  the drive never gets ready... 
+		 */
+		while ((difference & QIC_STATUS_READY) != 0) {
+			TRACE(ft_t_noise, "command %d issued while not ready",
+			      command);
+			TRACE(ft_t_noise, "waiting until drive gets ready");
+			if (ftape_ready_wait(ftape_timeout.seek,
+					     &status) == -EINTR) {
+				/*  Bail out on signal !
+				 */
+				TRACE_ABORT(-EINTR, ft_t_warn,
+				      "interrupted by non-blockable signal");
+			}
+			difference = ((status ^ qic117_cmds[command].state) &
+				      qic117_cmds[command].mask);
+		}
+		while ((difference & QIC_STATUS_ERROR) != 0) {
+			int err;
+			qic117_cmd_t cmd;
+
+			TRACE(ft_t_noise,
+			      "command %d issued while error pending",
+			      command);
+			TRACE(ft_t_noise, "clearing error status");
+			ftape_report_error(&err, &cmd, 1);
+			ftape_report_raw_drive_status(&status);
+			difference = ((status ^ qic117_cmds[command].state) &
+				      qic117_cmds[command].mask);
+			if ((difference & QIC_STATUS_ERROR) != 0) {
+				/*  Bail out on fatal signal !
+				 */
+				FT_SIGNAL_EXIT(_NEVER_BLOCK);
+			}
+		}
+		if (difference) {
+			/*  Any remaining difference can't be solved
+			 *  here.  
+			 */
+			if (difference & (QIC_STATUS_CARTRIDGE_PRESENT |
+					  QIC_STATUS_NEW_CARTRIDGE |
+					  QIC_STATUS_REFERENCED)) {
+				TRACE(ft_t_warn,
+				      "Fatal: tape removed or reinserted !");
+				ft_failure = 1;
+			} else {
+				TRACE(ft_t_err, "wrong state: 0x%02x should be: 0x%02x",
+				      status & qic117_cmds[command].mask,
+				      qic117_cmds[command].state);
+			}
+			TRACE_EXIT -EIO;
+		}
+		if (~status & QIC_STATUS_READY & qic117_cmds[command].mask) {
+			TRACE_ABORT(-EBUSY, ft_t_err, "Bad: still busy!");
+		}
+	}
+	TRACE_EXIT 0;
+}
+
+/*      Issue a tape command:
+ */
+int ftape_command(qic117_cmd_t command)
+{
+	int result = 0;
+	static int level;
+	TRACE_FUN(ft_t_any);
+
+	if ((unsigned int)command > NR_ITEMS(qic117_cmds)) {
+		/*  This is a bug we'll want to know about too.
+		 */
+		TRACE_ABORT(-EIO, ft_t_bug, "bug - bad command: %d", command);
+	}
+	if (++level > 5) { /*  This is a bug we'll want to know about. */
+		--level;
+		TRACE_ABORT(-EIO, ft_t_bug, "bug - recursion for command: %d",
+			    command);
+	}
+	/*  disable logging and restriction check for some commands,
+	 *  check all other commands that have a prescribed starting
+	 *  status.
+	 */
+	if (diagnostic_mode) {
+		TRACE(ft_t_flow, "diagnostic command %d", command);
+	} else if (command == QIC_REPORT_DRIVE_STATUS ||
+		   command == QIC_REPORT_NEXT_BIT) {
+		TRACE(ft_t_any, "%s", qic117_cmds[command].name);
+	} else {
+		TRACE_CATCH(ft_check_cmd_restrictions(command), --level);
+	}
+	/*  Now all conditions are met or result was < 0.
+	 */
+	result = ft_send_to_drive((unsigned int)command);
+	if (qic117_cmds[command].cmd_type == motion &&
+	    command != QIC_LOGICAL_FORWARD && command != QIC_STOP_TAPE) {
+		ft_location.known = 0;
+	}
+	ftape_current_command = command;
+	--level;
+	TRACE_EXIT result;
+}
+
+/*      Send a tape command parameter:
+ *      Generates command # of step pulses.
+ *      Skips tape-status call !
+ */
+int ftape_parameter(unsigned int parameter)
+{
+	TRACE_FUN(ft_t_any);
+
+	TRACE(ft_t_flow, "called with parameter = %d", parameter);
+	TRACE_EXIT ft_send_to_drive(parameter + 2);
+}
+
+/*      Wait for the drive to get ready.
+ *      timeout time in milli-seconds
+ *      Returned status is valid if result != -EIO
+ *
+ *      Should we allow to be killed by SIGINT?  (^C)
+ *      Would be nice at least for large timeouts.
+ */
+int ftape_ready_wait(unsigned int timeout, int *status)
+{
+	unsigned long t0;
+	unsigned int poll_delay;
+	int signal_retries;
+	TRACE_FUN(ft_t_any);
+
+	/*  the following ** REALLY ** reduces the system load when
+	 *  e.g. one simply rewinds or retensions. The tape is slow 
+	 *  anyway. It is really not necessary to detect error 
+	 *  conditions with 1/10 seconds granularity
+	 *
+	 *  On my AMD 133MHZ 486: 100 ms: 23% system load
+	 *                        1  sec:  5%
+	 *                        5  sec:  0.6%, yeah
+	 */
+	if (timeout <= FT_SECOND) {
+		poll_delay = 100 * FT_MILLISECOND;
+		signal_retries = 20; /* two seconds */
+	} else if (timeout < 20 * FT_SECOND) {
+		TRACE(ft_t_flow, "setting poll delay to 1 second");
+		poll_delay = FT_SECOND;
+		signal_retries = 2; /* two seconds */
+	} else {
+		TRACE(ft_t_flow, "setting poll delay to 5 seconds");
+		poll_delay = 5 * FT_SECOND;
+		signal_retries = 1; /* five seconds */
+	}
+	for (;;) {
+		t0 = jiffies;
+		TRACE_CATCH(ftape_report_raw_drive_status(status),);
+		if (*status & QIC_STATUS_READY) {
+			TRACE_EXIT 0;
+		}
+		if (!signal_retries--) {
+			FT_SIGNAL_EXIT(_NEVER_BLOCK);
+		}
+		if ((int)timeout >= 0) {
+			/* this will fail when jiffies wraps around about
+			 * once every year :-)
+			 */
+			timeout -= ((jiffies - t0) * FT_SECOND) / HZ;
+			if (timeout <= 0) {
+				TRACE_ABORT(-ETIME, ft_t_err, "timeout");
+			}
+			ftape_sleep(poll_delay);
+			timeout -= poll_delay;
+		} else {
+			ftape_sleep(poll_delay);
+		}
+	}
+	TRACE_EXIT -ETIME;
+}
+
+/*      Issue command and wait up to timeout milli seconds for drive ready
+ */
+int ftape_command_wait(qic117_cmd_t command, unsigned int timeout, int *status)
+{
+	int result;
+
+	/* Drive should be ready, issue command
+	 */
+	result = ftape_command(command);
+	if (result >= 0) {
+		result = ftape_ready_wait(timeout, status);
+	}
+	return result;
+}
+
+static int ftape_parameter_wait(unsigned int parm, unsigned int timeout, int *status)
+{
+	int result;
+
+	/* Drive should be ready, issue command
+	 */
+	result = ftape_parameter(parm);
+	if (result >= 0) {
+		result = ftape_ready_wait(timeout, status);
+	}
+	return result;
+}
+
+/*--------------------------------------------------------------------------
+ *      Report operations
+ */
+
+/* Query the drive about its status.  The command is sent and
+   result_length bits of status are returned (2 extra bits are read
+   for start and stop). */
+
+int ftape_report_operation(int *status,
+			   qic117_cmd_t command,
+			   int result_length)
+{
+	int i, st3;
+	unsigned int t0;
+	unsigned int dt;
+	TRACE_FUN(ft_t_any);
+
+	TRACE_CATCH(ftape_command(command),);
+	t0 = ftape_timestamp();
+	i = 0;
+	do {
+		++i;
+		ftape_sleep(3 * FT_MILLISECOND);	/* see remark below */
+		TRACE_CATCH(fdc_sense_drive_status(&st3),);
+		dt = ftape_timediff(t0, ftape_timestamp());
+		/*  Ack should be asserted within Ttimout + Tack = 6 msec.
+		 *  Looks like some drives fail to do this so extend this
+		 *  period to 300 msec.
+		 */
+	} while (!(st3 & ST3_TRACK_0) && dt < 300000);
+	if (!(st3 & ST3_TRACK_0)) {
+		TRACE(ft_t_err,
+		      "No acknowledge after %u msec. (%i iter)", dt / 1000, i);
+		TRACE_ABORT(-EIO, ft_t_err, "timeout on Acknowledge");
+	}
+	/*  dt may be larger than expected because of other tasks
+	 *  scheduled while we were sleeping.
+	 */
+	if (i > 1 && dt > 6000) {
+		TRACE(ft_t_err, "Acknowledge after %u msec. (%i iter)",
+		      dt / 1000, i);
+	}
+	*status = 0;
+	for (i = 0; i < result_length + 1; i++) {
+		TRACE_CATCH(ftape_command(QIC_REPORT_NEXT_BIT),);
+		TRACE_CATCH(fdc_sense_drive_status(&st3),);
+		if (i < result_length) {
+			*status |= ((st3 & ST3_TRACK_0) ? 1 : 0) << i;
+		} else if ((st3 & ST3_TRACK_0) == 0) {
+			TRACE_ABORT(-EIO, ft_t_err, "missing status stop bit");
+		}
+	}
+	/* this command will put track zero and index back into normal state */
+	(void)ftape_command(QIC_REPORT_NEXT_BIT);
+	TRACE_EXIT 0;
+}
+
+/* Report the current drive status. */
+
+int ftape_report_raw_drive_status(int *status)
+{
+	int result;
+	int count = 0;
+	TRACE_FUN(ft_t_any);
+
+	do {
+		result = ftape_report_operation(status,
+						QIC_REPORT_DRIVE_STATUS, 8);
+	} while (result < 0 && ++count <= 3);
+	if (result < 0) {
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "report_operation failed after %d trials", count);
+	}
+	if ((*status & 0xff) == 0xff) {
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "impossible drive status 0xff");
+	}
+	if (*status & QIC_STATUS_READY) {
+		ftape_current_command = QIC_NO_COMMAND; /* completed */
+	}
+	ft_last_status.status.drive_status = (__u8)(*status & 0xff);
+	TRACE_EXIT 0;
+}
+
+int ftape_report_drive_status(int *status)
+{
+	TRACE_FUN(ft_t_any);
+
+	TRACE_CATCH(ftape_report_raw_drive_status(status),);
+	if (*status & QIC_STATUS_NEW_CARTRIDGE ||
+	    !(*status & QIC_STATUS_CARTRIDGE_PRESENT)) {
+		ft_failure = 1;	/* will inhibit further operations */
+		TRACE_EXIT -EIO;
+	}
+	if (*status & QIC_STATUS_READY && *status & QIC_STATUS_ERROR) {
+		/*  Let caller handle all errors */
+		TRACE_ABORT(1, ft_t_warn, "warning: error status set!");
+	}
+	TRACE_EXIT 0;
+}
+
+int ftape_report_error(unsigned int *error,
+		       qic117_cmd_t *command, int report)
+{
+	static const ftape_error ftape_errors[] = QIC117_ERRORS;
+	int code;
+	TRACE_FUN(ft_t_any);
+
+	TRACE_CATCH(ftape_report_operation(&code, QIC_REPORT_ERROR_CODE, 16),);
+	*error   = (unsigned int)(code & 0xff);
+	*command = (qic117_cmd_t)((code>>8)&0xff);
+	/*  remember hardware status, maybe useful for status ioctls
+	 */
+	ft_last_error.error.command = (__u8)*command;
+	ft_last_error.error.error   = (__u8)*error;
+	if (!report) {
+		TRACE_EXIT 0;
+	}
+	if (*error == 0) {
+		TRACE_ABORT(0, ft_t_info, "No error");
+	}
+	TRACE(ft_t_info, "errorcode: %d", *error);
+	if (*error < NR_ITEMS(ftape_errors)) {
+		TRACE(ft_t_noise, "%sFatal ERROR:",
+		      (ftape_errors[*error].fatal ? "" : "Non-"));
+		TRACE(ft_t_noise, "%s ...", ftape_errors[*error].message);
+	} else {
+		TRACE(ft_t_noise, "Unknown ERROR !");
+	}
+	if ((unsigned int)*command < NR_ITEMS(qic117_cmds) &&
+	    qic117_cmds[*command].name != NULL) {
+		TRACE(ft_t_noise, "... caused by command \'%s\'",
+		      qic117_cmds[*command].name);
+	} else {
+		TRACE(ft_t_noise, "... caused by unknown command %d",
+		      *command);
+	}
+	TRACE_EXIT 0;
+}
+
+int ftape_report_configuration(qic_model *model,
+			       unsigned int *rate,
+			       int *qic_std,
+			       int *tape_len)
+{
+	int result;
+	int config;
+	int status;
+	static const unsigned int qic_rates[ 4] = { 250, 2000, 500, 1000 };
+	TRACE_FUN(ft_t_any);
+
+	result = ftape_report_operation(&config,
+					QIC_REPORT_DRIVE_CONFIGURATION, 8);
+	if (result < 0) {
+		ft_last_status.status.drive_config = (__u8)0x00;
+		*model = prehistoric;
+		*rate = 500;
+		*qic_std = QIC_TAPE_QIC40;
+		*tape_len = 205;
+		TRACE_EXIT 0;
+	} else {
+		ft_last_status.status.drive_config = (__u8)(config & 0xff);
+	}
+	*rate = qic_rates[(config & QIC_CONFIG_RATE_MASK) >> QIC_CONFIG_RATE_SHIFT];
+	result = ftape_report_operation(&status, QIC_REPORT_TAPE_STATUS, 8);
+	if (result < 0) {
+		ft_last_status.status.tape_status = (__u8)0x00;
+		/* pre- QIC117 rev C spec. drive, QIC_CONFIG_80 bit is valid.
+		 */
+		*qic_std = (config & QIC_CONFIG_80) ?
+			QIC_TAPE_QIC80 : QIC_TAPE_QIC40;
+		/* ?? how's about 425ft tapes? */
+		*tape_len = (config & QIC_CONFIG_LONG) ? 307 : 0;
+		*model = pre_qic117c;
+		result = 0;
+	} else {
+		ft_last_status.status.tape_status = (__u8)(status & 0xff);
+		*model = post_qic117b;
+		TRACE(ft_t_any, "report tape status result = %02x", status);
+		/* post- QIC117 rev C spec. drive, QIC_CONFIG_80 bit is
+		 * invalid. 
+		 */
+		switch (status & QIC_TAPE_STD_MASK) {
+		case QIC_TAPE_QIC40:
+		case QIC_TAPE_QIC80:
+		case QIC_TAPE_QIC3020:
+		case QIC_TAPE_QIC3010:
+			*qic_std = status & QIC_TAPE_STD_MASK;
+			break;
+		default:
+			*qic_std = -1;
+			break;
+		}
+		switch (status & QIC_TAPE_LEN_MASK) {
+		case QIC_TAPE_205FT:
+			/* 205 or 425+ ft 550 Oe tape */
+			*tape_len = 0;
+			break;
+		case QIC_TAPE_307FT:
+			/* 307.5 ft 550 Oe Extended Length (XL) tape */
+			*tape_len = 307;
+			break;
+		case QIC_TAPE_VARIABLE:
+			/* Variable length 550 Oe tape */
+			*tape_len = 0;
+			break;
+		case QIC_TAPE_1100FT:
+			/* 1100 ft 550 Oe tape */
+			*tape_len = 1100;
+			break;
+		case QIC_TAPE_FLEX:
+			/* Variable length 900 Oe tape */
+			*tape_len = 0;
+			break;
+		default:
+			*tape_len = -1;
+			break;
+		}
+		if (*qic_std == -1 || *tape_len == -1) {
+			TRACE(ft_t_any,
+			      "post qic-117b spec drive with unknown tape");
+		}
+		result = *tape_len == -1 ? -EIO : 0;
+		if (status & QIC_TAPE_WIDE) {
+			switch (*qic_std) {
+			case QIC_TAPE_QIC80:
+				TRACE(ft_t_info, "TR-1 tape detected");
+				break;
+			case QIC_TAPE_QIC3010:
+				TRACE(ft_t_info, "TR-2 tape detected");
+				break;
+			case QIC_TAPE_QIC3020:
+				TRACE(ft_t_info, "TR-3 tape detected");
+				break;
+			default:
+				TRACE(ft_t_warn,
+				      "Unknown Travan tape type detected");
+				break;
+			}
+		}
+	}
+	TRACE_EXIT (result < 0) ? -EIO : 0;
+}
+
+static int ftape_report_rom_version(int *version)
+{
+
+	if (ftape_report_operation(version, QIC_REPORT_ROM_VERSION, 8) < 0) {
+		return -EIO;
+	} else {
+		return 0;
+	}
+}
+
+void ftape_report_vendor_id(unsigned int *id)
+{
+	int result;
+	TRACE_FUN(ft_t_any);
+
+	/* We'll try to get a vendor id from the drive.  First
+	 * according to the QIC-117 spec, a 16-bit id is requested.
+	 * If that fails we'll try an 8-bit version, otherwise we'll
+	 * try an undocumented query.
+	 */
+	result = ftape_report_operation((int *) id, QIC_REPORT_VENDOR_ID, 16);
+	if (result < 0) {
+		result = ftape_report_operation((int *) id,
+						QIC_REPORT_VENDOR_ID, 8);
+		if (result < 0) {
+			/* The following is an undocumented call found
+			 * in the CMS code.
+			 */
+			result = ftape_report_operation((int *) id, 24, 8);
+			if (result < 0) {
+				*id = UNKNOWN_VENDOR;
+			} else {
+				TRACE(ft_t_noise, "got old 8 bit id: %04x",
+				      *id);
+				*id |= 0x20000;
+			}
+		} else {
+			TRACE(ft_t_noise, "got 8 bit id: %04x", *id);
+			*id |= 0x10000;
+		}
+	} else {
+		TRACE(ft_t_noise, "got 16 bit id: %04x", *id);
+	}
+	if (*id == 0x0047) {
+		int version;
+		int sign;
+
+		if (ftape_report_rom_version(&version) < 0) {
+			TRACE(ft_t_bug, "report rom version failed");
+			TRACE_EXIT;
+		}
+		TRACE(ft_t_noise, "CMS rom version: %d", version);
+		ftape_command(QIC_ENTER_DIAGNOSTIC_1);
+		ftape_command(QIC_ENTER_DIAGNOSTIC_1);
+		diagnostic_mode = 1;
+		if (ftape_report_operation(&sign, 9, 8) < 0) {
+			unsigned int error;
+			qic117_cmd_t command;
+
+			ftape_report_error(&error, &command, 1);
+			ftape_command(QIC_ENTER_PRIMARY_MODE);
+			diagnostic_mode = 0;
+			TRACE_EXIT;	/* failure ! */
+		} else {
+			TRACE(ft_t_noise, "CMS signature: %02x", sign);
+		}
+		if (sign == 0xa5) {
+			result = ftape_report_operation(&sign, 37, 8);
+			if (result < 0) {
+				if (version >= 63) {
+					*id = 0x8880;
+					TRACE(ft_t_noise,
+					      "This is an Iomega drive !");
+				} else {
+					*id = 0x0047;
+					TRACE(ft_t_noise,
+					      "This is a real CMS drive !");
+				}
+			} else {
+				*id = 0x0047;
+				TRACE(ft_t_noise, "CMS status: %d", sign);
+			}
+		} else {
+			*id = UNKNOWN_VENDOR;
+		}
+		ftape_command(QIC_ENTER_PRIMARY_MODE);
+		diagnostic_mode = 0;
+	}
+	TRACE_EXIT;
+}
+
+static int qic_rate_code(unsigned int rate)
+{
+	switch (rate) {
+	case 250:
+		return QIC_CONFIG_RATE_250;
+	case 500:
+		return QIC_CONFIG_RATE_500;
+	case 1000:
+		return QIC_CONFIG_RATE_1000;
+	case 2000:
+		return QIC_CONFIG_RATE_2000;
+	default:
+		return QIC_CONFIG_RATE_500;
+	}
+}
+
+static int ftape_set_rate_test(unsigned int *max_rate)
+{
+	unsigned int error;
+	qic117_cmd_t command;
+	int status;
+	int supported = 0;
+	TRACE_FUN(ft_t_any);
+
+	/*  Check if the drive does support the select rate command
+	 *  by testing all different settings. If any one is accepted
+	 *  we assume the command is supported, else not.
+	 */
+	for (*max_rate = 2000; *max_rate >= 250; *max_rate /= 2) {
+		if (ftape_command(QIC_SELECT_RATE) < 0) {
+			continue;
+		}		
+		if (ftape_parameter_wait(qic_rate_code(*max_rate),
+					 1 * FT_SECOND, &status) < 0) {
+			continue;
+		}
+		if (status & QIC_STATUS_ERROR) {
+			ftape_report_error(&error, &command, 0);
+			continue;
+		}
+		supported = 1; /* did accept a request */
+		break;
+	}
+	TRACE(ft_t_noise, "Select Rate command is%s supported", 
+	      supported ? "" : " not");
+	TRACE_EXIT supported;
+}
+
+int ftape_set_data_rate(unsigned int new_rate /* Kbps */, unsigned int qic_std)
+{
+	int status;
+	int result = 0;
+	unsigned int data_rate = new_rate;
+	static int supported;
+	int rate_changed = 0;
+	qic_model dummy_model;
+	unsigned int dummy_qic_std, dummy_tape_len;
+	TRACE_FUN(ft_t_any);
+
+	if (ft_drive_max_rate == 0) { /* first time */
+		supported = ftape_set_rate_test(&ft_drive_max_rate);
+	}
+	if (supported) {
+		ftape_command(QIC_SELECT_RATE);
+		result = ftape_parameter_wait(qic_rate_code(new_rate),
+					      1 * FT_SECOND, &status);
+		if (result >= 0 && !(status & QIC_STATUS_ERROR)) {
+			rate_changed = 1;
+		}
+	}
+	TRACE_CATCH(result = ftape_report_configuration(&dummy_model,
+							&data_rate, 
+							&dummy_qic_std,
+							&dummy_tape_len),);
+	if (data_rate != new_rate) {
+		if (!supported) {
+			TRACE(ft_t_warn, "Rate change not supported!");
+		} else if (rate_changed) {
+			TRACE(ft_t_warn, "Requested: %d, got %d",
+			      new_rate, data_rate);
+		} else {
+			TRACE(ft_t_warn, "Rate change failed!");
+		}
+		result = -EINVAL;
+	}
+	/*
+	 *  Set data rate and write precompensation as specified:
+	 *
+	 *            |  QIC-40/80  | QIC-3010/3020
+	 *   rate     |   precomp   |    precomp
+	 *  ----------+-------------+--------------
+	 *  250 Kbps. |   250 ns.   |     0 ns.
+	 *  500 Kbps. |   125 ns.   |     0 ns.
+	 *    1 Mbps. |    42 ns.   |     0 ns.
+	 *    2 Mbps  |      N/A    |     0 ns.
+	 */
+	if ((qic_std == QIC_TAPE_QIC40 && data_rate > 500) || 
+	    (qic_std == QIC_TAPE_QIC80 && data_rate > 1000)) {
+		TRACE_ABORT(-EINVAL,
+			    ft_t_warn, "Datarate too high for QIC-mode");
+	}
+	TRACE_CATCH(fdc_set_data_rate(data_rate),_res = -EINVAL);
+	ft_data_rate = data_rate;
+	if (qic_std == QIC_TAPE_QIC40 || qic_std == QIC_TAPE_QIC80) {
+		switch (data_rate) {
+		case 250:
+			fdc_set_write_precomp(250);
+			break;
+		default:
+		case 500:
+			fdc_set_write_precomp(125);
+			break;
+		case 1000:
+			fdc_set_write_precomp(42);
+			break;
+		}
+	} else {
+		fdc_set_write_precomp(0);
+	}
+	TRACE_EXIT result;
+}
+
+/*  The next two functions are used to cope with excessive overrun errors
+ */
+int ftape_increase_threshold(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (fdc.type < i82077 || ft_fdc_threshold >= 12) {
+		TRACE_ABORT(-EIO, ft_t_err, "cannot increase fifo threshold");
+	}
+	if (fdc_fifo_threshold(++ft_fdc_threshold, NULL, NULL, NULL) < 0) {
+		TRACE(ft_t_err, "cannot increase fifo threshold");
+		ft_fdc_threshold --;
+		fdc_reset();
+	}
+	TRACE(ft_t_info, "New FIFO threshold: %d", ft_fdc_threshold);
+	TRACE_EXIT 0;
+}
+
+int ftape_half_data_rate(void)
+{
+	if (ft_data_rate < 500) {
+		return -1;
+	}
+	if (ftape_set_data_rate(ft_data_rate / 2, ft_qic_std) < 0) {
+		return -EIO;
+	}
+	ftape_calc_timeouts(ft_qic_std, ft_data_rate, ftape_tape_len);
+	return 0;
+}
+
+/*      Seek the head to the specified track.
+ */
+int ftape_seek_head_to_track(unsigned int track)
+{
+	int status;
+	TRACE_FUN(ft_t_any);
+
+	ft_location.track = -1; /* remains set in case of error */
+	if (track >= ft_tracks_per_tape) {
+		TRACE_ABORT(-EINVAL, ft_t_bug, "track out of bounds");
+	}
+	TRACE(ft_t_flow, "seeking track %d", track);
+	TRACE_CATCH(ftape_command(QIC_SEEK_HEAD_TO_TRACK),);
+	TRACE_CATCH(ftape_parameter_wait(track, ftape_timeout.head_seek,
+					 &status),);
+	ft_location.track = track;
+	ftape_might_be_off_track = 0;
+	TRACE_EXIT 0;
+}
+
+int ftape_wakeup_drive(wake_up_types method)
+{
+	int status;
+	int motor_on = 0;
+	TRACE_FUN(ft_t_any);
+
+	switch (method) {
+	case wake_up_colorado:
+		TRACE_CATCH(ftape_command(QIC_PHANTOM_SELECT),);
+		TRACE_CATCH(ftape_parameter(0 /* ft_drive_sel ?? */),);
+		break;
+	case wake_up_mountain:
+		TRACE_CATCH(ftape_command(QIC_SOFT_SELECT),);
+		ftape_sleep(FT_MILLISECOND);	/* NEEDED */
+		TRACE_CATCH(ftape_parameter(18),);
+		break;
+	case wake_up_insight:
+		ftape_sleep(100 * FT_MILLISECOND);
+		motor_on = 1;
+		fdc_motor(motor_on);	/* enable is done by motor-on */
+	case no_wake_up:
+		break;
+	default:
+		TRACE_EXIT -ENODEV;	/* unknown wakeup method */
+		break;
+	}
+	/*  If wakeup succeeded we shouldn't get an error here..
+	 */
+	TRACE_CATCH(ftape_report_raw_drive_status(&status),
+		    if (motor_on) {
+			    fdc_motor(0);
+		    });
+	TRACE_EXIT 0;
+}
+
+int ftape_put_drive_to_sleep(wake_up_types method)
+{
+	TRACE_FUN(ft_t_any);
+
+	switch (method) {
+	case wake_up_colorado:
+		TRACE_CATCH(ftape_command(QIC_PHANTOM_DESELECT),);
+		break;
+	case wake_up_mountain:
+		TRACE_CATCH(ftape_command(QIC_SOFT_DESELECT),);
+		break;
+	case wake_up_insight:
+		fdc_motor(0);	/* enable is done by motor-on */
+	case no_wake_up:	/* no wakeup / no sleep ! */
+		break;
+	default:
+		TRACE_EXIT -ENODEV;	/* unknown wakeup method */
+	}
+	TRACE_EXIT 0;
+}
+
+int ftape_reset_drive(void)
+{
+	int result = 0;
+	int status;
+	unsigned int err_code;
+	qic117_cmd_t err_command;
+	int i;
+	TRACE_FUN(ft_t_any);
+
+	/*  We want to re-establish contact with our drive.  Fire a
+	 *  number of reset commands (single step pulses) and pray for
+	 *  success.
+	 */
+	for (i = 0; i < 2; ++i) {
+		TRACE(ft_t_flow, "Resetting fdc");
+		fdc_reset();
+		ftape_sleep(10 * FT_MILLISECOND);
+		TRACE(ft_t_flow, "Reset command to drive");
+		result = ftape_command(QIC_RESET);
+		if (result == 0) {
+			ftape_sleep(1 * FT_SECOND); /*  drive not
+						     *  accessible
+						     *  during 1 second
+						     */
+			TRACE(ft_t_flow, "Re-selecting drive");
+
+			/* Strange, the QIC-117 specs don't mention
+			 * this but the drive gets deselected after a
+			 * soft reset !  So we need to enable it
+			 * again.
+			 */
+			if (ftape_wakeup_drive(ft_drive_type.wake_up) < 0) {
+				TRACE(ft_t_err, "Wakeup failed !");
+			}
+			TRACE(ft_t_flow, "Waiting until drive gets ready");
+			result= ftape_ready_wait(ftape_timeout.reset, &status);
+			if (result == 0 && (status & QIC_STATUS_ERROR)) {
+				result = ftape_report_error(&err_code,
+							    &err_command, 1);
+				if (result == 0 && err_code == 27) {
+					/*  Okay, drive saw reset
+					 *  command and responded as it
+					 *  should
+					 */
+					break;
+				} else {
+					result = -EIO;
+				}
+			} else {
+				result = -EIO;
+			}
+		}
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+	}
+	if (result != 0) {
+		TRACE(ft_t_err, "General failure to reset tape drive");
+	} else {
+		/*  Restore correct settings: keep original rate 
+		 */
+		ftape_set_data_rate(ft_data_rate, ft_qic_std);
+	}
+	ftape_init_drive_needed = 1;
+	TRACE_EXIT result;
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-io.h b/drivers/char/ftape/lowlevel/ftape-io.h
new file mode 100644
index 0000000..26a7baa
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-io.h
@@ -0,0 +1,90 @@
+#ifndef _FTAPE_IO_H
+#define _FTAPE_IO_H
+
+/*
+ * Copyright (C) 1993-1996 Bas Laarhoven,
+ *           (C) 1997      Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-io.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:18 $
+ *
+ *      This file contains definitions for the glue part of the
+ *      QIC-40/80/3010/3020 floppy-tape driver "ftape" for Linux.
+ */
+
+#include <linux/qic117.h>
+#include <linux/ftape-vendors.h>
+
+typedef struct {
+	unsigned int seek;
+	unsigned int reset;
+	unsigned int rewind;
+	unsigned int head_seek;
+	unsigned int stop;
+	unsigned int pause;
+} ft_timeout_table;
+
+typedef enum {
+	prehistoric, pre_qic117c, post_qic117b, post_qic117d 
+} qic_model;
+
+/*
+ *      ftape-io.c defined global vars.
+ */
+extern ft_timeout_table ftape_timeout;
+extern unsigned int ftape_tape_len;
+extern volatile qic117_cmd_t ftape_current_command;
+extern const struct qic117_command_table qic117_cmds[];
+extern int ftape_might_be_off_track;
+
+/*
+ *      ftape-io.c defined global functions.
+ */
+extern void ftape_udelay(unsigned int usecs);
+extern void  ftape_udelay_calibrate(void);
+extern void ftape_sleep(unsigned int time);
+extern void ftape_report_vendor_id(unsigned int *id);
+extern int  ftape_command(qic117_cmd_t command);
+extern int  ftape_command_wait(qic117_cmd_t command,
+			       unsigned int timeout,
+			       int *status);
+extern int  ftape_parameter(unsigned int parameter);
+extern int ftape_report_operation(int *status,
+				  qic117_cmd_t  command,
+				  int result_length);
+extern int ftape_report_configuration(qic_model *model,
+				      unsigned int *rate,
+				      int *qic_std,
+				      int *tape_len);
+extern int ftape_report_drive_status(int *status);
+extern int ftape_report_raw_drive_status(int *status);
+extern int ftape_report_status(int *status);
+extern int ftape_ready_wait(unsigned int timeout, int *status);
+extern int ftape_seek_head_to_track(unsigned int track);
+extern int ftape_set_data_rate(unsigned int new_rate, unsigned int qic_std);
+extern int ftape_report_error(unsigned int *error,
+			      qic117_cmd_t *command,
+			      int report);
+extern int ftape_reset_drive(void);
+extern int ftape_put_drive_to_sleep(wake_up_types method);
+extern int ftape_wakeup_drive(wake_up_types method);
+extern int ftape_increase_threshold(void);
+extern int ftape_half_data_rate(void);
+
+#endif
diff --git a/drivers/char/ftape/lowlevel/ftape-proc.c b/drivers/char/ftape/lowlevel/ftape-proc.c
new file mode 100644
index 0000000..c66251e
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-proc.c
@@ -0,0 +1,215 @@
+/*
+ *      Copyright (C) 1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-proc.c,v $
+ * $Revision: 1.11 $
+ * $Date: 1997/10/24 14:47:37 $
+ *
+ *      This file contains the procfs interface for the
+ *      QIC-40/80/3010/3020 floppy-tape driver "ftape" for Linux.
+
+ *	Old code removed, switched to dynamic proc entry.
+ */
+
+#include <linux/config.h>
+
+#if defined(CONFIG_PROC_FS) && defined(CONFIG_FT_PROC_FS)
+
+#include <linux/proc_fs.h>
+
+#include <linux/ftape.h>
+#include <linux/init.h>
+#include <linux/qic117.h>
+
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-proc.h"
+#include "../lowlevel/ftape-tracing.h"
+
+static size_t get_driver_info(char *buf)
+{
+	const char *debug_level[] = { "bugs"  ,
+				      "errors",
+				      "warnings",
+				      "informational",
+				      "noisy",
+				      "program flow",
+				      "fdc and dma",
+				      "data flow",
+				      "anything" };
+
+	return sprintf(buf,
+		       "version       : %s\n"
+		       "used data rate: %d kbit/sec\n"
+		       "dma memory    : %d kb\n"
+		       "debug messages: %s\n",
+		       FTAPE_VERSION,
+		       ft_data_rate,
+		       FT_BUFF_SIZE * ft_nr_buffers >> 10,
+		       debug_level[TRACE_LEVEL]);
+}
+
+static size_t get_tapedrive_info(char *buf)
+{ 
+	return sprintf(buf,
+		       "vendor id : 0x%04x\n"
+		       "drive name: %s\n"
+		       "wind speed: %d ips\n"
+		       "wakeup    : %s\n"
+		       "max. rate : %d kbit/sec\n",
+		       ft_drive_type.vendor_id,
+		       ft_drive_type.name,
+		       ft_drive_type.speed,
+		       ((ft_drive_type.wake_up == no_wake_up)
+			? "No wakeup needed" :
+			((ft_drive_type.wake_up == wake_up_colorado)
+			 ? "Colorado" :
+			 ((ft_drive_type.wake_up == wake_up_mountain)
+			  ? "Mountain" :
+			  ((ft_drive_type.wake_up == wake_up_insight)
+			   ? "Motor on" :
+			   "Unknown")))),
+		       ft_drive_max_rate);
+}
+
+static size_t get_cartridge_info(char *buf)
+{
+	if (ftape_init_drive_needed) {
+		return sprintf(buf, "uninitialized\n");
+	}
+	if (ft_no_tape) {
+		return sprintf(buf, "no cartridge inserted\n");
+	}
+	return sprintf(buf,
+		       "segments  : %5d\n"
+		       "tracks    : %5d\n"
+		       "length    : %5dft\n"
+		       "formatted : %3s\n"
+		       "writable  : %3s\n"
+		       "QIC spec. : QIC-%s\n"
+		       "fmt-code  : %1d\n",
+		       ft_segments_per_track,
+		       ft_tracks_per_tape,
+		       ftape_tape_len,
+		       (ft_formatted == 1) ? "yes" : "no",
+		       (ft_write_protected == 1) ? "no" : "yes",
+		       ((ft_qic_std == QIC_TAPE_QIC40) ? "40" :
+			((ft_qic_std == QIC_TAPE_QIC80) ? "80" :
+			 ((ft_qic_std == QIC_TAPE_QIC3010) ? "3010" :
+			  ((ft_qic_std == QIC_TAPE_QIC3020) ? "3020" :
+			   "???")))),
+		       ft_format_code);
+}
+
+static size_t get_controller_info(char *buf)
+{
+	const char  *fdc_name[] = { "no fdc",
+				    "i8272",
+				    "i82077",
+				    "i82077AA",
+				    "Colorado FC-10 or FC-20",
+				    "i82078",
+				    "i82078_1" };
+
+	return sprintf(buf,
+		       "FDC type  : %s\n"
+		       "FDC base  : 0x%03x\n"
+		       "FDC irq   : %d\n"
+		       "FDC dma   : %d\n"
+		       "FDC thr.  : %d\n"
+		       "max. rate : %d kbit/sec\n",
+		       ft_mach2 ? "Mountain MACH-2" : fdc_name[fdc.type],
+		       fdc.sra, fdc.irq, fdc.dma,
+		       ft_fdc_threshold, ft_fdc_max_rate);
+}
+
+static size_t get_history_info(char *buf)
+{
+        size_t len;
+
+	len  = sprintf(buf,
+		       "\nFDC isr statistics\n"
+		       " id_am_errors     : %3d\n"
+		       " id_crc_errors    : %3d\n"
+		       " data_am_errors   : %3d\n"
+		       " data_crc_errors  : %3d\n"
+		       " overrun_errors   : %3d\n"
+		       " no_data_errors   : %3d\n"
+		       " retries          : %3d\n",
+		       ft_history.id_am_errors,   ft_history.id_crc_errors,
+		       ft_history.data_am_errors, ft_history.data_crc_errors,
+		       ft_history.overrun_errors, ft_history.no_data_errors,
+		       ft_history.retries);
+	len += sprintf(buf + len,
+		       "\nECC statistics\n"
+		       " crc_errors       : %3d\n"
+		       " crc_failures     : %3d\n"
+		       " ecc_failures     : %3d\n"
+		       " sectors corrected: %3d\n",
+		       ft_history.crc_errors,   ft_history.crc_failures,
+		       ft_history.ecc_failures, ft_history.corrected);
+	len += sprintf(buf + len,
+		       "\ntape quality statistics\n"
+		       " media defects    : %3d\n",
+		       ft_history.defects);
+	len += sprintf(buf + len,
+		       "\ntape motion statistics\n"
+		       " repositions      : %3d\n",
+		       ft_history.rewinds);
+	return len;
+}
+
+static int ftape_read_proc(char *page, char **start, off_t off,
+			   int count, int *eof, void *data)
+{
+	char *ptr = page;
+	size_t len;
+	
+	ptr += sprintf(ptr, "Kernel Driver\n\n");
+	ptr += get_driver_info(ptr);
+	ptr += sprintf(ptr, "\nTape Drive\n\n");
+	ptr += get_tapedrive_info(ptr);
+	ptr += sprintf(ptr, "\nFDC Controller\n\n");
+	ptr += get_controller_info(ptr);
+	ptr += sprintf(ptr, "\nTape Cartridge\n\n");
+	ptr += get_cartridge_info(ptr);
+	ptr += sprintf(ptr, "\nHistory Record\n\n");
+	ptr += get_history_info(ptr);
+
+	len = strlen(page);
+	*start = NULL;
+	if (off+count >= len) {
+		*eof = 1;
+	} else {
+		*eof = 0;
+	}
+	return len;
+}
+
+int __init ftape_proc_init(void)
+{
+	return create_proc_read_entry("ftape", 0, &proc_root,
+		ftape_read_proc, NULL) != NULL;
+}
+
+void ftape_proc_destroy(void)
+{
+	remove_proc_entry("ftape", &proc_root);
+}
+
+#endif /* defined(CONFIG_PROC_FS) && defined(CONFIG_FT_PROC_FS) */
diff --git a/drivers/char/ftape/lowlevel/ftape-proc.h b/drivers/char/ftape/lowlevel/ftape-proc.h
new file mode 100644
index 0000000..264dfcc
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-proc.h
@@ -0,0 +1,35 @@
+#ifndef _FTAPE_PROC_H
+#define _FTAPE_PROC_H
+
+/*
+ *      Copyright (C) 1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-proc.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:20 $
+ *
+ *      This file contains definitions for the procfs interface of the
+ *      QIC-40/80/3010/3020 floppy-tape driver "ftape" for Linux.
+ */
+
+#include <linux/proc_fs.h>
+
+extern int  ftape_proc_init(void);
+extern void ftape_proc_destroy(void);
+
+#endif
diff --git a/drivers/char/ftape/lowlevel/ftape-read.c b/drivers/char/ftape/lowlevel/ftape-read.c
new file mode 100644
index 0000000..d967d8c
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-read.c
@@ -0,0 +1,621 @@
+/*
+ *      Copyright (C) 1993-1996 Bas Laarhoven,
+ *                (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-read.c,v $
+ * $Revision: 1.6 $
+ * $Date: 1997/10/21 14:39:22 $
+ *
+ *      This file contains the reading code
+ *      for the QIC-117 floppy-tape driver for Linux.
+ *
+ */
+
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+
+#include <linux/ftape.h>
+#include <linux/qic117.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-read.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-write.h"
+#include "../lowlevel/ftape-ecc.h"
+#include "../lowlevel/ftape-bsm.h"
+
+/*      Global vars.
+ */
+
+/*      Local vars.
+ */
+
+void ftape_zap_read_buffers(void)
+{
+	int i;
+
+	for (i = 0; i < ft_nr_buffers; ++i) {
+/*  changed to "fit" with dynamic allocation of tape_buffer. --khp  */
+		ft_buffer[i]->status = waiting;
+		ft_buffer[i]->bytes = 0;
+		ft_buffer[i]->skip = 0;
+		ft_buffer[i]->retry = 0;
+	}
+/*	ftape_reset_buffer(); */
+}
+
+static SectorMap convert_sector_map(buffer_struct * buff)
+{
+	int i = 0;
+	SectorMap bad_map = ftape_get_bad_sector_entry(buff->segment_id);
+	SectorMap src_map = buff->soft_error_map | buff->hard_error_map;
+	SectorMap dst_map = 0;
+	TRACE_FUN(ft_t_any);
+
+	if (bad_map || src_map) {
+		TRACE(ft_t_flow, "bad_map = 0x%08lx", (long) bad_map);
+		TRACE(ft_t_flow, "src_map = 0x%08lx", (long) src_map);
+	}
+	while (bad_map) {
+		while ((bad_map & 1) == 0) {
+			if (src_map & 1) {
+				dst_map |= (1 << i);
+			}
+			src_map >>= 1;
+			bad_map >>= 1;
+			++i;
+		}
+		/* (bad_map & 1) == 1 */
+		src_map >>= 1;
+		bad_map >>= 1;
+	}
+	if (src_map) {
+		dst_map |= (src_map << i);
+	}
+	if (dst_map) {
+		TRACE(ft_t_flow, "dst_map = 0x%08lx", (long) dst_map);
+	}
+	TRACE_EXIT dst_map;
+}
+
+static int correct_and_copy_fraction(buffer_struct *buff, __u8 * destination,
+				     int start, int size)
+{
+	struct memory_segment mseg;
+	int result;
+	SectorMap read_bad;
+	TRACE_FUN(ft_t_any);
+
+	mseg.read_bad = convert_sector_map(buff);
+	mseg.marked_bad = 0;	/* not used... */
+	mseg.blocks = buff->bytes / FT_SECTOR_SIZE;
+	mseg.data = buff->address;
+	/*    If there are no data sectors we can skip this segment.
+	 */
+	if (mseg.blocks <= 3) {
+		TRACE_ABORT(0, ft_t_noise, "empty segment");
+	}
+	read_bad = mseg.read_bad;
+	ft_history.crc_errors += count_ones(read_bad);
+	result = ftape_ecc_correct_data(&mseg);
+	if (read_bad != 0 || mseg.corrected != 0) {
+		TRACE(ft_t_noise, "crc error map: 0x%08lx", (unsigned long)read_bad);
+		TRACE(ft_t_noise, "corrected map: 0x%08lx", (unsigned long)mseg.corrected);
+		ft_history.corrected += count_ones(mseg.corrected);
+	}
+	if (result == ECC_CORRECTED || result == ECC_OK) {
+		if (result == ECC_CORRECTED) {
+			TRACE(ft_t_info, "ecc corrected segment: %d", buff->segment_id);
+		}
+		if(start < 0) {
+			start= 0;
+		}
+		if((start+size) > ((mseg.blocks - 3) * FT_SECTOR_SIZE)) {
+			size = (mseg.blocks - 3) * FT_SECTOR_SIZE  - start;
+		} 
+		if (size < 0) {
+			size= 0;
+		}
+		if(size > 0) {
+			memcpy(destination + start, mseg.data + start, size);
+		}
+		if ((read_bad ^ mseg.corrected) & mseg.corrected) {
+			/* sectors corrected without crc errors set */
+			ft_history.crc_failures++;
+		}
+		TRACE_EXIT size; /* (mseg.blocks - 3) * FT_SECTOR_SIZE; */
+	} else {
+		ft_history.ecc_failures++;
+		TRACE_ABORT(-EAGAIN,
+			    ft_t_err, "ecc failure on segment %d",
+			    buff->segment_id);
+	}
+	TRACE_EXIT 0;
+}
+
+/*      Read given segment into buffer at address.
+ */
+int ftape_read_segment_fraction(const int segment_id,
+				void  *address, 
+				const ft_read_mode_t read_mode,
+				const int start,
+				const int size)
+{
+	int result = 0;
+	int retry  = 0;
+	int bytes_read = 0;
+	int read_done  = 0;
+	TRACE_FUN(ft_t_flow);
+
+	ft_history.used |= 1;
+	TRACE(ft_t_data_flow, "segment_id = %d", segment_id);
+	if (ft_driver_state != reading) {
+		TRACE(ft_t_noise, "calling ftape_abort_operation");
+		TRACE_CATCH(ftape_abort_operation(),);
+		ftape_set_state(reading);
+	}
+	for(;;) {
+		buffer_struct *tail;
+		/*  Allow escape from this loop on signal !
+		 */
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		/*  Search all full buffers for the first matching the
+		 *  wanted segment.  Clear other buffers on the fly.
+		 */
+		tail = ftape_get_buffer(ft_queue_tail);
+		while (!read_done && tail->status == done) {
+			/*  Allow escape from this loop on signal !
+			 */
+			FT_SIGNAL_EXIT(_DONT_BLOCK);
+			if (tail->segment_id == segment_id) {
+				/*  If out buffer is already full,
+				 *  return its contents.  
+				 */
+				TRACE(ft_t_flow, "found segment in cache: %d",
+				      segment_id);
+				if (tail->deleted) {
+					/*  Return a value that
+					 *  read_header_segment
+					 *  understands.  As this
+					 *  should only occur when
+					 *  searching for the header
+					 *  segments it shouldn't be
+					 *  misinterpreted elsewhere.
+					 */
+					TRACE_EXIT 0;
+				}
+				result = correct_and_copy_fraction(
+					tail,
+					address,
+					start,
+					size);
+				TRACE(ft_t_flow, "segment contains (bytes): %d",
+				      result);
+				if (result < 0) {
+					if (result != -EAGAIN) {
+						TRACE_EXIT result;
+					}
+					/* keep read_done == 0, will
+					 * trigger
+					 * ftape_abort_operation
+					 * because reading wrong
+					 * segment.
+					 */
+					TRACE(ft_t_err, "ecc failed, retry");
+					++retry;
+				} else {
+					read_done = 1;
+					bytes_read = result;
+				}
+			} else {
+				TRACE(ft_t_flow,"zapping segment in cache: %d",
+				      tail->segment_id);
+			}
+			tail->status = waiting;
+			tail = ftape_next_buffer(ft_queue_tail);
+		}
+		if (!read_done && tail->status == reading) {
+			if (tail->segment_id == segment_id) {
+				switch(ftape_wait_segment(reading)) {
+				case 0:
+					break;
+				case -EINTR:
+					TRACE_ABORT(-EINTR, ft_t_warn,
+						    "interrupted by "
+						    "non-blockable signal");
+					break;
+				default:
+					TRACE(ft_t_noise,
+					      "wait_segment failed");
+					ftape_abort_operation();
+					ftape_set_state(reading);
+					break;
+				}
+			} else {
+				/*  We're reading the wrong segment,
+				 *  stop runner.
+				 */
+				TRACE(ft_t_noise, "reading wrong segment");
+				ftape_abort_operation();
+				ftape_set_state(reading);
+			}
+		}
+		/*    should runner stop ?
+		 */
+		if (ft_runner_status == aborting) {
+			buffer_struct *head = ftape_get_buffer(ft_queue_head);
+			switch(head->status) {
+			case error:
+				ft_history.defects += 
+					count_ones(head->hard_error_map);
+			case reading:
+				head->status = waiting;
+				break;
+			default:
+				break;
+			}
+			TRACE_CATCH(ftape_dumb_stop(),);
+		} else {
+			/*  If just passed last segment on tape: wait
+			 *  for BOT or EOT mark. Sets ft_runner_status to
+			 *  idle if at lEOT and successful 
+			 */
+			TRACE_CATCH(ftape_handle_logical_eot(),);
+		}
+		/*    If we got a segment: quit, or else retry up to limit.
+		 *
+		 *    If segment to read is empty, do not start runner for it,
+		 *    but wait for next read call.
+		 */
+		if (read_done ||
+		    ftape_get_bad_sector_entry(segment_id) == EMPTY_SEGMENT ) {
+			/* bytes_read = 0;  should still be zero */
+			TRACE_EXIT bytes_read;
+
+		}
+		if (retry > FT_RETRIES_ON_ECC_ERROR) {
+			ft_history.defects++;
+			TRACE_ABORT(-ENODATA, ft_t_err,
+				    "too many retries on ecc failure");
+		}
+		/*    Now at least one buffer is empty !
+		 *    Restart runner & tape if needed.
+		 */
+		TRACE(ft_t_any, "head: %d, tail: %d, ft_runner_status: %d",
+		      ftape_buffer_id(ft_queue_head),
+		      ftape_buffer_id(ft_queue_tail),
+		      ft_runner_status);
+		TRACE(ft_t_any, "buffer[].status, [head]: %d, [tail]: %d",
+		      ftape_get_buffer(ft_queue_head)->status,
+		      ftape_get_buffer(ft_queue_tail)->status);
+		tail = ftape_get_buffer(ft_queue_tail);
+		if (tail->status == waiting) {
+			buffer_struct *head = ftape_get_buffer(ft_queue_head);
+
+			ftape_setup_new_segment(head, segment_id, -1);
+			if (read_mode == FT_RD_SINGLE) {
+				/* disable read-ahead */
+				head->next_segment = 0;
+			}
+			ftape_calc_next_cluster(head);
+			if (ft_runner_status == idle) {
+				result = ftape_start_tape(segment_id,
+							  head->sector_offset);
+				if (result < 0) {
+					TRACE_ABORT(result, ft_t_err, "Error: "
+						    "segment %d unreachable",
+						    segment_id);
+				}
+			}
+			head->status = reading;
+			fdc_setup_read_write(head, FDC_READ);
+		}
+	}
+	/* not reached */
+	TRACE_EXIT -EIO;
+}
+
+int ftape_read_header_segment(__u8 *address)
+{
+	int result;
+	int header_segment;
+	int first_failed = 0;
+	int status;
+	TRACE_FUN(ft_t_flow);
+
+	ft_used_header_segment = -1;
+	TRACE_CATCH(ftape_report_drive_status(&status),);
+	TRACE(ft_t_flow, "reading...");
+	/*  We're looking for the first header segment.
+	 *  A header segment cannot contain bad sectors, therefor at the
+	 *  tape start, segments with bad sectors are (according to QIC-40/80)
+	 *  written with deleted data marks and must be skipped.
+	 */
+	memset(address, '\0', (FT_SECTORS_PER_SEGMENT - 3) * FT_SECTOR_SIZE); 
+	result = 0;
+#define HEADER_SEGMENT_BOUNDARY 68  /* why not 42? */
+	for (header_segment = 0;
+	     header_segment < HEADER_SEGMENT_BOUNDARY && result == 0;
+	     ++header_segment) {
+		/*  Set no read-ahead, the isr will force read-ahead whenever
+		 *  it encounters deleted data !
+		 */
+		result = ftape_read_segment(header_segment,
+					    address,
+					    FT_RD_SINGLE);
+		if (result < 0 && !first_failed) {
+			TRACE(ft_t_err, "header segment damaged, trying backup");
+			first_failed = 1;
+			result = 0;	/* force read of next (backup) segment */
+		}
+	}
+	if (result < 0 || header_segment >= HEADER_SEGMENT_BOUNDARY) {
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "no readable header segment found");
+	}
+	TRACE_CATCH(ftape_abort_operation(),);
+	ft_used_header_segment = header_segment;
+	result = ftape_decode_header_segment(address);
+ 	TRACE_EXIT result;
+}
+
+int ftape_decode_header_segment(__u8 *address)
+{
+	unsigned int max_floppy_side;
+	unsigned int max_floppy_track;
+	unsigned int max_floppy_sector;
+	unsigned int new_tape_len;
+	TRACE_FUN(ft_t_flow);
+
+	if (GET4(address, FT_SIGNATURE) == FT_D2G_MAGIC) {
+		/* Ditto 2GB header segment. They encrypt the bad sector map.
+		 * We decrypt it and store them in normal format.
+		 * I hope this is correct.
+		 */
+		int i;
+		TRACE(ft_t_warn,
+		      "Found Ditto 2GB tape, "
+		      "trying to decrypt bad sector map");
+		for (i=256; i < 29 * FT_SECTOR_SIZE; i++) {
+			address[i] = ~(address[i] - (i&0xff));
+		}
+		PUT4(address, 0,FT_HSEG_MAGIC);
+	} else if (GET4(address, FT_SIGNATURE) != FT_HSEG_MAGIC) {
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "wrong signature in header segment");
+	}
+	ft_format_code = (ft_format_type) address[FT_FMT_CODE];
+	if (ft_format_code != fmt_big) {
+		ft_header_segment_1   = GET2(address, FT_HSEG_1);
+		ft_header_segment_2   = GET2(address, FT_HSEG_2);
+		ft_first_data_segment = GET2(address, FT_FRST_SEG);
+		ft_last_data_segment  = GET2(address, FT_LAST_SEG);
+	} else {
+		ft_header_segment_1   = GET4(address, FT_6_HSEG_1);
+		ft_header_segment_2   = GET4(address, FT_6_HSEG_2);
+		ft_first_data_segment = GET4(address, FT_6_FRST_SEG);
+		ft_last_data_segment  = GET4(address, FT_6_LAST_SEG);
+	}
+	TRACE(ft_t_noise, "first data segment: %d", ft_first_data_segment);
+	TRACE(ft_t_noise, "last  data segment: %d", ft_last_data_segment);
+	TRACE(ft_t_noise, "header segments are %d and %d",
+	      ft_header_segment_1, ft_header_segment_2);
+
+	/*    Verify tape parameters...
+	 *    QIC-40/80 spec:                 tape_parameters:
+	 *
+	 *    segments-per-track              segments_per_track
+	 *    tracks-per-cartridge            tracks_per_tape
+	 *    max-floppy-side                 (segments_per_track *
+	 *                                    tracks_per_tape - 1) /
+	 *                                    ftape_segments_per_head
+	 *    max-floppy-track                ftape_segments_per_head /
+	 *                                    ftape_segments_per_cylinder - 1
+	 *    max-floppy-sector               ftape_segments_per_cylinder *
+	 *                                    FT_SECTORS_PER_SEGMENT
+	 */
+	ft_segments_per_track = GET2(address, FT_SPT);
+	ft_tracks_per_tape    = address[FT_TPC];
+	max_floppy_side       = address[FT_FHM];
+	max_floppy_track      = address[FT_FTM];
+	max_floppy_sector     = address[FT_FSM];
+	TRACE(ft_t_noise, "(fmt/spt/tpc/fhm/ftm/fsm) = %d/%d/%d/%d/%d/%d",
+	      ft_format_code, ft_segments_per_track, ft_tracks_per_tape,
+	      max_floppy_side, max_floppy_track, max_floppy_sector);
+	new_tape_len = ftape_tape_len;
+	switch (ft_format_code) {
+	case fmt_425ft:
+		new_tape_len = 425;
+		break;
+	case fmt_normal:
+		if (ftape_tape_len == 0) {	/* otherwise 307 ft */
+			new_tape_len = 205;
+		}
+		break;
+	case fmt_1100ft:
+		new_tape_len = 1100;
+		break;
+	case fmt_var:{
+			int segments_per_1000_inch = 1;		/* non-zero default for switch */
+			switch (ft_qic_std) {
+			case QIC_TAPE_QIC40:
+				segments_per_1000_inch = 332;
+				break;
+			case QIC_TAPE_QIC80:
+				segments_per_1000_inch = 488;
+				break;
+			case QIC_TAPE_QIC3010:
+				segments_per_1000_inch = 730;
+				break;
+			case QIC_TAPE_QIC3020:
+				segments_per_1000_inch = 1430;
+				break;
+			}
+			new_tape_len = (1000 * ft_segments_per_track +
+					(segments_per_1000_inch - 1)) / segments_per_1000_inch;
+			break;
+		}
+	case fmt_big:{
+			int segments_per_1000_inch = 1;		/* non-zero default for switch */
+			switch (ft_qic_std) {
+			case QIC_TAPE_QIC40:
+				segments_per_1000_inch = 332;
+				break;
+			case QIC_TAPE_QIC80:
+				segments_per_1000_inch = 488;
+				break;
+			case QIC_TAPE_QIC3010:
+				segments_per_1000_inch = 730;
+				break;
+			case QIC_TAPE_QIC3020:
+				segments_per_1000_inch = 1430;
+				break;
+			default:
+				TRACE_ABORT(-EIO, ft_t_bug,
+			"%x QIC-standard with fmt-code %d, please report",
+					    ft_qic_std, ft_format_code);
+			}
+			new_tape_len = ((1000 * ft_segments_per_track +
+					 (segments_per_1000_inch - 1)) / 
+					segments_per_1000_inch);
+			break;
+		}
+	default:
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "unknown tape format, please report !");
+	}
+	if (new_tape_len != ftape_tape_len) {
+		ftape_tape_len = new_tape_len;
+		TRACE(ft_t_info, "calculated tape length is %d ft",
+		      ftape_tape_len);
+		ftape_calc_timeouts(ft_qic_std, ft_data_rate, ftape_tape_len);
+	}
+	if (ft_segments_per_track == 0 && ft_tracks_per_tape == 0 &&
+	    max_floppy_side == 0 && max_floppy_track == 0 &&
+	    max_floppy_sector == 0) {
+		/*  QIC-40 Rev E and earlier has no values in the header.
+		 */
+		ft_segments_per_track = 68;
+		ft_tracks_per_tape = 20;
+		max_floppy_side = 1;
+		max_floppy_track = 169;
+		max_floppy_sector = 128;
+	}
+	/*  This test will compensate for the wrong parameter on tapes
+	 *  formatted by Conner software.
+	 */
+	if (ft_segments_per_track == 150 &&
+	    ft_tracks_per_tape == 28 &&
+	    max_floppy_side == 7 &&
+	    max_floppy_track == 149 &&
+	    max_floppy_sector == 128) {
+TRACE(ft_t_info, "the famous CONNER bug: max_floppy_side off by one !");
+		max_floppy_side = 6;
+	}
+	/*  These tests will compensate for the wrong parameter on tapes
+	 *  formatted by ComByte Windows software.
+	 *
+	 *  First, for 205 foot tapes
+	 */
+	if (ft_segments_per_track == 100 &&
+	    ft_tracks_per_tape == 28 &&
+	    max_floppy_side == 9 &&
+	    max_floppy_track == 149 &&
+	    max_floppy_sector == 128) {
+TRACE(ft_t_info, "the ComByte bug: max_floppy_side incorrect!");
+		max_floppy_side = 4;
+	}
+	/* Next, for 307 foot tapes. */
+	if (ft_segments_per_track == 150 &&
+	    ft_tracks_per_tape == 28 &&
+	    max_floppy_side == 9 &&
+	    max_floppy_track == 149 &&
+	    max_floppy_sector == 128) {
+TRACE(ft_t_info, "the ComByte bug: max_floppy_side incorrect!");
+		max_floppy_side = 6;
+	}
+	/*  This test will compensate for the wrong parameter on tapes
+	 *  formatted by Colorado Windows software.
+	 */
+	if (ft_segments_per_track == 150 &&
+	    ft_tracks_per_tape == 28 &&
+	    max_floppy_side == 6 &&
+	    max_floppy_track == 150 &&
+	    max_floppy_sector == 128) {
+TRACE(ft_t_info, "the famous Colorado bug: max_floppy_track off by one !");
+		max_floppy_track = 149;
+	}
+	ftape_segments_per_head = ((max_floppy_sector/FT_SECTORS_PER_SEGMENT) *
+				   (max_floppy_track + 1));
+	/*  This test will compensate for some bug reported by Dima
+	 *  Brodsky.  Seems to be a Colorado bug, either. (freebee
+	 *  Imation tape shipped together with Colorado T3000
+	 */
+	if ((ft_format_code == fmt_var || ft_format_code == fmt_big) &&
+	    ft_tracks_per_tape == 50 &&
+	    max_floppy_side == 54 &&
+	    max_floppy_track == 255 &&
+	    max_floppy_sector == 128) {
+TRACE(ft_t_info, "the famous ??? bug: max_floppy_track off by one !");
+		max_floppy_track = 254;
+	}
+	/*
+	 *    Verify drive_configuration with tape parameters
+	 */
+	if (ftape_segments_per_head == 0 || ftape_segments_per_cylinder == 0 ||
+	  ((ft_segments_per_track * ft_tracks_per_tape - 1) / ftape_segments_per_head
+	   != max_floppy_side) ||
+	    (ftape_segments_per_head / ftape_segments_per_cylinder - 1 != max_floppy_track) ||
+	(ftape_segments_per_cylinder * FT_SECTORS_PER_SEGMENT != max_floppy_sector)
+#ifdef TESTING
+	    || ((ft_format_code == fmt_var || ft_format_code == fmt_big) && 
+		(max_floppy_track != 254 || max_floppy_sector != 128))
+#endif
+	   ) {
+		char segperheadz = ftape_segments_per_head ? ' ' : '?';
+		char segpercylz  = ftape_segments_per_cylinder ? ' ' : '?';
+		TRACE(ft_t_err,"Tape parameters inconsistency, please report");
+		TRACE(ft_t_err, "reported = %d/%d/%d/%d/%d/%d",
+		      ft_format_code,
+		      ft_segments_per_track,
+		      ft_tracks_per_tape,
+		      max_floppy_side,
+		      max_floppy_track,
+		      max_floppy_sector);
+		TRACE(ft_t_err, "required = %d/%d/%d/%d%c/%d%c/%d",
+		      ft_format_code,
+		      ft_segments_per_track,
+		      ft_tracks_per_tape,
+		      ftape_segments_per_head ?
+		      ((ft_segments_per_track * ft_tracks_per_tape -1) / 
+		       ftape_segments_per_head ) :
+			(ft_segments_per_track * ft_tracks_per_tape -1),
+			segperheadz,
+		      ftape_segments_per_cylinder ?
+		      (ftape_segments_per_head / 
+		       ftape_segments_per_cylinder - 1 ) :
+			ftape_segments_per_head - 1,
+			segpercylz,
+		      (ftape_segments_per_cylinder * FT_SECTORS_PER_SEGMENT));
+		TRACE_EXIT -EIO;
+	}
+	ftape_extract_bad_sector_map(address);
+ 	TRACE_EXIT 0;
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-read.h b/drivers/char/ftape/lowlevel/ftape-read.h
new file mode 100644
index 0000000..069f99f
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-read.h
@@ -0,0 +1,51 @@
+#ifndef _FTAPE_READ_H
+#define _FTAPE_READ_H
+
+/*
+ * Copyright (C) 1994-1996 Bas Laarhoven,
+ *           (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-read.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:22 $
+ *
+ *      This file contains the definitions for the read functions
+ *      for the QIC-117 floppy-tape driver for Linux.
+ *
+ */
+
+/*      ftape-read.c defined global functions.
+ */
+typedef enum {
+	FT_RD_SINGLE = 0,
+	FT_RD_AHEAD  = 1,
+} ft_read_mode_t;
+
+extern int ftape_read_header_segment(__u8 *address);
+extern int ftape_decode_header_segment(__u8 *address);
+extern int ftape_read_segment_fraction(const int segment,
+				       void  *address, 
+				       const ft_read_mode_t read_mode,
+				       const int start,
+				       const int size);
+#define ftape_read_segment(segment, address, read_mode)			\
+	ftape_read_segment_fraction(segment, address, read_mode,	\
+				    0, FT_SEGMENT_SIZE)
+extern void ftape_zap_read_buffers(void);
+
+#endif				/* _FTAPE_READ_H */
diff --git a/drivers/char/ftape/lowlevel/ftape-rw.c b/drivers/char/ftape/lowlevel/ftape-rw.c
new file mode 100644
index 0000000..c0d6dc2
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-rw.c
@@ -0,0 +1,1092 @@
+/*
+ *      Copyright (C) 1993-1996 Bas Laarhoven,
+ *                (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-rw.c,v $
+ * $Revision: 1.7 $
+ * $Date: 1997/10/28 14:26:49 $
+ *
+ *      This file contains some common code for the segment read and
+ *      segment write routines for the QIC-117 floppy-tape driver for
+ *      Linux.
+ */
+
+#include <linux/string.h>
+#include <linux/errno.h>
+
+#include <linux/ftape.h>
+#include <linux/qic117.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/fdc-io.h"
+#include "../lowlevel/ftape-init.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-read.h"
+#include "../lowlevel/ftape-ecc.h"
+#include "../lowlevel/ftape-bsm.h"
+
+/*      Global vars.
+ */
+int ft_nr_buffers;
+buffer_struct *ft_buffer[FT_MAX_NR_BUFFERS];
+static volatile int ft_head;
+static volatile int ft_tail;	/* not volatile but need same type as head */
+int fdc_setup_error;
+location_record ft_location = {-1, 0};
+volatile int ftape_tape_running;
+
+/*      Local vars.
+ */
+static int overrun_count_offset;
+static int inhibit_correction;
+
+/*  maxmimal allowed overshoot when fast seeking
+ */
+#define OVERSHOOT_LIMIT 10
+
+/*      Increment cyclic buffer nr.
+ */
+buffer_struct *ftape_next_buffer(ft_buffer_queue_t pos)
+{
+	switch (pos) {
+	case ft_queue_head:
+		if (++ft_head >= ft_nr_buffers) {
+			ft_head = 0;
+		}
+		return ft_buffer[ft_head];
+	case ft_queue_tail:
+		if (++ft_tail >= ft_nr_buffers) {
+			ft_tail = 0;
+		}
+		return ft_buffer[ft_tail];
+	default:
+		return NULL;
+	}
+}
+int ftape_buffer_id(ft_buffer_queue_t pos)
+{
+	switch(pos) {
+	case ft_queue_head: return ft_head;
+	case ft_queue_tail: return ft_tail;
+	default: return -1;
+	}
+}
+buffer_struct *ftape_get_buffer(ft_buffer_queue_t pos)
+{
+	switch(pos) {
+	case ft_queue_head: return ft_buffer[ft_head];
+	case ft_queue_tail: return ft_buffer[ft_tail];
+	default: return NULL;
+	}
+}
+void ftape_reset_buffer(void)
+{
+	ft_head = ft_tail = 0;
+}
+
+buffer_state_enum ftape_set_state(buffer_state_enum new_state)
+{
+	buffer_state_enum old_state = ft_driver_state;
+
+	ft_driver_state = new_state;
+	return old_state;
+}
+/*      Calculate Floppy Disk Controller and DMA parameters for a segment.
+ *      head:   selects buffer struct in array.
+ *      offset: number of physical sectors to skip (including bad ones).
+ *      count:  number of physical sectors to handle (including bad ones).
+ */
+static int setup_segment(buffer_struct * buff, 
+			 int segment_id,
+			 unsigned int sector_offset, 
+			 unsigned int sector_count, 
+			 int retry)
+{
+	SectorMap offset_mask;
+	SectorMap mask;
+	TRACE_FUN(ft_t_any);
+
+	buff->segment_id = segment_id;
+	buff->sector_offset = sector_offset;
+	buff->remaining = sector_count;
+	buff->head = segment_id / ftape_segments_per_head;
+	buff->cyl = (segment_id % ftape_segments_per_head) / ftape_segments_per_cylinder;
+	buff->sect = (segment_id % ftape_segments_per_cylinder) * FT_SECTORS_PER_SEGMENT + 1;
+	buff->deleted = 0;
+	offset_mask = (1 << buff->sector_offset) - 1;
+	mask = ftape_get_bad_sector_entry(segment_id) & offset_mask;
+	while (mask) {
+		if (mask & 1) {
+			offset_mask >>= 1;	/* don't count bad sector */
+		}
+		mask >>= 1;
+	}
+	buff->data_offset = count_ones(offset_mask);	/* good sectors to skip */
+	buff->ptr = buff->address + buff->data_offset * FT_SECTOR_SIZE;
+	TRACE(ft_t_flow, "data offset = %d sectors", buff->data_offset);
+	if (retry) {
+		buff->soft_error_map &= offset_mask;	/* keep skipped part */
+	} else {
+		buff->hard_error_map = buff->soft_error_map = 0;
+	}
+	buff->bad_sector_map = ftape_get_bad_sector_entry(buff->segment_id);
+	if (buff->bad_sector_map != 0) {
+		TRACE(ft_t_noise, "segment: %d, bad sector map: %08lx",
+			buff->segment_id, (long)buff->bad_sector_map);
+	} else {
+		TRACE(ft_t_flow, "segment: %d", buff->segment_id);
+	}
+	if (buff->sector_offset > 0) {
+		buff->bad_sector_map >>= buff->sector_offset;
+	}
+	if (buff->sector_offset != 0 || buff->remaining != FT_SECTORS_PER_SEGMENT) {
+		TRACE(ft_t_flow, "sector offset = %d, count = %d",
+			buff->sector_offset, buff->remaining);
+	}
+	/*    Segments with 3 or less sectors are not written with valid
+	 *    data because there is no space left for the ecc.  The
+	 *    data written is whatever happens to be in the buffer.
+	 *    Reading such a segment will return a zero byte-count.
+	 *    To allow us to read/write segments with all bad sectors
+	 *    we fake one readable sector in the segment. This
+	 *    prevents having to handle these segments in a very
+	 *    special way.  It is not important if the reading of this
+	 *    bad sector fails or not (the data is ignored). It is
+	 *    only read to keep the driver running.
+	 *
+	 *    The QIC-40/80 spec. has no information on how to handle
+	 *    this case, so this is my interpretation.  
+	 */
+	if (buff->bad_sector_map == EMPTY_SEGMENT) {
+		TRACE(ft_t_flow, "empty segment %d, fake first sector good",
+		      buff->segment_id);
+		if (buff->ptr != buff->address) {
+			TRACE(ft_t_bug, "This is a bug: %p/%p",
+			      buff->ptr, buff->address);
+		}
+		buff->bad_sector_map = FAKE_SEGMENT;
+	}
+	fdc_setup_error = 0;
+	buff->next_segment = segment_id + 1;
+	TRACE_EXIT 0;
+}
+
+/*      Calculate Floppy Disk Controller and DMA parameters for a new segment.
+ */
+int ftape_setup_new_segment(buffer_struct * buff, int segment_id, int skip)
+{
+	int result = 0;
+	static int old_segment_id = -1;
+	static buffer_state_enum old_ft_driver_state = idle;
+	int retry = 0;
+	unsigned offset = 0;
+	int count = FT_SECTORS_PER_SEGMENT;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_flow, "%s segment %d (old = %d)",
+	      (ft_driver_state == reading || ft_driver_state == verifying) 
+	      ? "reading" : "writing",
+	      segment_id, old_segment_id);
+	if (ft_driver_state != old_ft_driver_state) {	/* when verifying */
+		old_segment_id = -1;
+		old_ft_driver_state = ft_driver_state;
+	}
+	if (segment_id == old_segment_id) {
+		++buff->retry;
+		++ft_history.retries;
+		TRACE(ft_t_flow, "setting up for retry nr %d", buff->retry);
+		retry = 1;
+		if (skip && buff->skip > 0) {	/* allow skip on retry */
+			offset = buff->skip;
+			count -= offset;
+			TRACE(ft_t_flow, "skipping %d sectors", offset);
+		}
+	} else {
+		buff->retry = 0;
+		buff->skip = 0;
+		old_segment_id = segment_id;
+	}
+	result = setup_segment(buff, segment_id, offset, count, retry);
+	TRACE_EXIT result;
+}
+
+/*      Determine size of next cluster of good sectors.
+ */
+int ftape_calc_next_cluster(buffer_struct * buff)
+{
+	/* Skip bad sectors.
+	 */
+	while (buff->remaining > 0 && (buff->bad_sector_map & 1) != 0) {
+		buff->bad_sector_map >>= 1;
+		++buff->sector_offset;
+		--buff->remaining;
+	}
+	/* Find next cluster of good sectors
+	 */
+	if (buff->bad_sector_map == 0) {	/* speed up */
+		buff->sector_count = buff->remaining;
+	} else {
+		SectorMap map = buff->bad_sector_map;
+
+		buff->sector_count = 0;
+		while (buff->sector_count < buff->remaining && (map & 1) == 0) {
+			++buff->sector_count;
+			map >>= 1;
+		}
+	}
+	return buff->sector_count;
+}
+
+/*  if just passed the last segment on a track, wait for BOT
+ *  or EOT mark.
+ */
+int ftape_handle_logical_eot(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (ft_runner_status == logical_eot) {
+		int status;
+
+		TRACE(ft_t_noise, "tape at logical EOT");
+		TRACE_CATCH(ftape_ready_wait(ftape_timeout.seek, &status),);
+		if ((status & (QIC_STATUS_AT_BOT | QIC_STATUS_AT_EOT)) == 0) {
+			TRACE_ABORT(-EIO, ft_t_err, "eot/bot not reached");
+		}
+		ft_runner_status = end_of_tape;
+	}
+	if (ft_runner_status == end_of_tape) {
+		TRACE(ft_t_noise, "runner stopped because of logical EOT");
+		ft_runner_status = idle;
+	}
+	TRACE_EXIT 0;
+}
+
+static int check_bot_eot(int status)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (status & (QIC_STATUS_AT_BOT | QIC_STATUS_AT_EOT)) {
+		ft_location.bot = ((ft_location.track & 1) == 0 ?
+				(status & QIC_STATUS_AT_BOT) != 0:
+				(status & QIC_STATUS_AT_EOT) != 0);
+		ft_location.eot = !ft_location.bot;
+		ft_location.segment = (ft_location.track +
+			(ft_location.bot ? 0 : 1)) * ft_segments_per_track - 1;
+		ft_location.sector = -1;
+		ft_location.known  = 1;
+		TRACE(ft_t_flow, "tape at logical %s",
+		      ft_location.bot ? "bot" : "eot");
+		TRACE(ft_t_flow, "segment = %d", ft_location.segment);
+	} else {
+		ft_location.known = 0;
+	}
+	TRACE_EXIT ft_location.known;
+}
+
+/*      Read Id of first sector passing tape head.
+ */
+static int ftape_read_id(void)
+{
+	int status;
+	__u8 out[2];
+	TRACE_FUN(ft_t_any);
+
+	/* Assume tape is running on entry, be able to handle
+	 * situation where it stopped or is stopping.
+	 */
+	ft_location.known = 0;	/* default is location not known */
+	out[0] = FDC_READID;
+	out[1] = ft_drive_sel;
+	TRACE_CATCH(fdc_command(out, 2),);
+	switch (fdc_interrupt_wait(20 * FT_SECOND)) {
+	case 0:
+		if (fdc_sect == 0) {
+			if (ftape_report_drive_status(&status) >= 0 &&
+			    (status & QIC_STATUS_READY)) {
+				ftape_tape_running = 0;
+				TRACE(ft_t_flow, "tape has stopped");
+				check_bot_eot(status);
+			}
+		} else {
+			ft_location.known = 1;
+			ft_location.segment = (ftape_segments_per_head
+					       * fdc_head
+					       + ftape_segments_per_cylinder
+					       * fdc_cyl
+					       + (fdc_sect - 1)
+					       / FT_SECTORS_PER_SEGMENT);
+			ft_location.sector = ((fdc_sect - 1)
+					      % FT_SECTORS_PER_SEGMENT);
+			ft_location.eot = ft_location.bot = 0;
+		}
+		break;
+	case -ETIME:
+		/*  Didn't find id on tape, must be near end: Wait
+		 *  until stopped.
+		 */
+		if (ftape_ready_wait(FT_FOREVER, &status) >= 0) {
+			ftape_tape_running = 0;
+			TRACE(ft_t_flow, "tape has stopped");
+			check_bot_eot(status);
+		}
+		break;
+	default:
+		/*  Interrupted or otherwise failing
+		 *  fdc_interrupt_wait() 
+		 */
+		TRACE(ft_t_err, "fdc_interrupt_wait failed");
+		break;
+	}
+	if (!ft_location.known) {
+		TRACE_ABORT(-EIO, ft_t_flow, "no id found");
+	}
+	if (ft_location.sector == 0) {
+		TRACE(ft_t_flow, "passing segment %d/%d",
+		      ft_location.segment, ft_location.sector);
+	} else {
+		TRACE(ft_t_fdc_dma, "passing segment %d/%d",
+		      ft_location.segment, ft_location.sector);
+	}
+	TRACE_EXIT 0;
+}
+
+static int logical_forward(void)
+{
+	ftape_tape_running = 1;
+	return ftape_command(QIC_LOGICAL_FORWARD);
+}
+
+int ftape_stop_tape(int *pstatus)
+{
+	int retry = 0;
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	do {
+		result = ftape_command_wait(QIC_STOP_TAPE,
+					    ftape_timeout.stop, pstatus);
+		if (result == 0) {
+			if ((*pstatus & QIC_STATUS_READY) == 0) {
+				result = -EIO;
+			} else {
+				ftape_tape_running = 0;
+			}
+		}
+	} while (result < 0 && ++retry <= 3);
+	if (result < 0) {
+		TRACE(ft_t_err, "failed ! (fatal)");
+	}
+	TRACE_EXIT result;
+}
+
+int ftape_dumb_stop(void)
+{
+	int result;
+	int status;
+	TRACE_FUN(ft_t_flow);
+
+	/*  Abort current fdc operation if it's busy (probably read
+	 *  or write operation pending) with a reset.
+	 */
+	if (fdc_ready_wait(100 /* usec */) < 0) {
+		TRACE(ft_t_noise, "aborting fdc operation");
+		fdc_reset();
+	}
+	/*  Reading id's after the last segment on a track may fail
+	 *  but eventually the drive will become ready (logical eot).
+	 */
+	result = ftape_report_drive_status(&status);
+	ft_location.known = 0;
+	do {
+		if (result == 0 && status & QIC_STATUS_READY) {
+			/* Tape is not running any more.
+			 */
+			TRACE(ft_t_noise, "tape already halted");
+			check_bot_eot(status);
+			ftape_tape_running = 0;
+		} else if (ftape_tape_running) {
+			/*  Tape is (was) still moving.
+			 */
+#ifdef TESTING
+			ftape_read_id();
+#endif
+			result = ftape_stop_tape(&status);
+		} else {
+			/*  Tape not yet ready but stopped.
+			 */
+			result = ftape_ready_wait(ftape_timeout.pause,&status);
+		}
+	} while (ftape_tape_running
+		 && !(sigtestsetmask(&current->pending.signal, _NEVER_BLOCK)));
+#ifndef TESTING
+	ft_location.known = 0;
+#endif
+	if (ft_runner_status == aborting || ft_runner_status == do_abort) {
+		ft_runner_status = idle;
+	}
+	TRACE_EXIT result;
+}
+
+/*      Wait until runner has finished tail buffer.
+ *
+ */
+int ftape_wait_segment(buffer_state_enum state)
+{
+	int status;
+	int result = 0;
+	TRACE_FUN(ft_t_flow);
+
+	while (ft_buffer[ft_tail]->status == state) {
+		TRACE(ft_t_flow, "state: %d", ft_buffer[ft_tail]->status);
+		/*  First buffer still being worked on, wait up to timeout.
+		 *
+		 *  Note: we check two times for being killed. 50
+		 *  seconds are quite long. Note that
+		 *  fdc_interrupt_wait() is not killable by any
+		 *  means. ftape_read_segment() wants us to return
+		 *  -EINTR in case of a signal.  
+		 */
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		result = fdc_interrupt_wait(50 * FT_SECOND);
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		if (result < 0) {
+			TRACE_ABORT(result,
+				    ft_t_err, "fdc_interrupt_wait failed");
+		}
+		if (fdc_setup_error) {
+			/* recover... FIXME */
+			TRACE_ABORT(-EIO, ft_t_err, "setup error");
+		}
+	}
+	if (ft_buffer[ft_tail]->status != error) {
+		TRACE_EXIT 0;
+	}
+	TRACE_CATCH(ftape_report_drive_status(&status),);
+	TRACE(ft_t_noise, "ftape_report_drive_status: 0x%02x", status);
+	if ((status & QIC_STATUS_READY) && 
+	    (status & QIC_STATUS_ERROR)) {
+		unsigned int error;
+		qic117_cmd_t command;
+		
+		/*  Report and clear error state.
+		 *  In case the drive can't operate at the selected
+		 *  rate, select the next lower data rate.
+		 */
+		ftape_report_error(&error, &command, 1);
+		if (error == 31 && command == QIC_LOGICAL_FORWARD) {
+			/* drive does not accept this data rate */
+			if (ft_data_rate > 250) {
+				TRACE(ft_t_info,
+				      "Probable data rate conflict");
+				TRACE(ft_t_info,
+				      "Lowering data rate to %d Kbps",
+				      ft_data_rate / 2);
+				ftape_half_data_rate();
+				if (ft_buffer[ft_tail]->retry > 0) {
+					/* give it a chance */
+					--ft_buffer[ft_tail]->retry;
+				}
+			} else {
+				/* no rate is accepted... */
+				TRACE(ft_t_err, "We're dead :(");
+			}
+		} else {
+			TRACE(ft_t_err, "Unknown error");
+		}
+		TRACE_EXIT -EIO;   /* g.p. error */
+	}
+	TRACE_EXIT 0;
+}
+
+/* forward */ static int seek_forward(int segment_id, int fast);
+
+static int fast_seek(int count, int reverse)
+{
+	int result = 0;
+	int status;
+	TRACE_FUN(ft_t_flow);
+
+	if (count > 0) {
+		/*  If positioned at begin or end of tape, fast seeking needs
+		 *  special treatment.
+		 *  Starting from logical bot needs a (slow) seek to the first
+		 *  segment before the high speed seek. Most drives do this
+		 *  automatically but some older don't, so we treat them
+		 *  all the same.
+		 *  Starting from logical eot is even more difficult because
+		 *  we cannot (slow) reverse seek to the last segment.
+		 *  TO BE IMPLEMENTED.
+		 */
+		inhibit_correction = 0;
+		if (ft_location.known &&
+		    ((ft_location.bot && !reverse) ||
+		     (ft_location.eot && reverse))) {
+			if (!reverse) {
+				/*  (slow) skip to first segment on a track
+				 */
+				seek_forward(ft_location.track * ft_segments_per_track, 0);
+				--count;
+			} else {
+				/*  When seeking backwards from
+				 *  end-of-tape the number of erased
+				 *  gaps found seems to be higher than
+				 *  expected.  Therefor the drive must
+				 *  skip some more segments than
+				 *  calculated, but we don't know how
+				 *  many.  Thus we will prevent the
+				 *  re-calculation of offset and
+				 *  overshoot when seeking backwards.
+				 */
+				inhibit_correction = 1;
+				count += 3;	/* best guess */
+			}
+		}
+	} else {
+		TRACE(ft_t_flow, "warning: zero or negative count: %d", count);
+	}
+	if (count > 0) {
+		int i;
+		int nibbles = count > 255 ? 3 : 2;
+
+		if (count > 4095) {
+			TRACE(ft_t_noise, "skipping clipped at 4095 segment");
+			count = 4095;
+		}
+		/* Issue this tape command first. */
+		if (!reverse) {
+			TRACE(ft_t_noise, "skipping %d segment(s)", count);
+			result = ftape_command(nibbles == 3 ?
+			   QIC_SKIP_EXTENDED_FORWARD : QIC_SKIP_FORWARD);
+		} else {
+			TRACE(ft_t_noise, "backing up %d segment(s)", count);
+			result = ftape_command(nibbles == 3 ?
+			   QIC_SKIP_EXTENDED_REVERSE : QIC_SKIP_REVERSE);
+		}
+		if (result < 0) {
+			TRACE(ft_t_noise, "Skip command failed");
+		} else {
+			--count;	/* 0 means one gap etc. */
+			for (i = 0; i < nibbles; ++i) {
+				if (result >= 0) {
+					result = ftape_parameter(count & 15);
+					count /= 16;
+				}
+			}
+			result = ftape_ready_wait(ftape_timeout.rewind, &status);
+			if (result >= 0) {
+				ftape_tape_running = 0;
+			}
+		}
+	}
+	TRACE_EXIT result;
+}
+
+static int validate(int id)
+{
+	/* Check to see if position found is off-track as reported
+	 *  once.  Because all tracks in one direction lie next to
+	 *  each other, if off-track the error will be approximately
+	 *  2 * ft_segments_per_track.
+	 */
+	if (ft_location.track == -1) {
+		return 1; /* unforseen situation, don't generate error */
+	} else {
+		/* Use margin of ft_segments_per_track on both sides
+		 * because ftape needs some margin and the error we're
+		 * looking for is much larger !
+		 */
+		int lo = (ft_location.track - 1) * ft_segments_per_track;
+		int hi = (ft_location.track + 2) * ft_segments_per_track;
+
+		return (id >= lo && id < hi);
+	}
+}
+
+static int seek_forward(int segment_id, int fast)
+{
+	int failures = 0;
+	int count;
+	static int margin = 1;	/* fixed: stop this before target */
+	static int overshoot = 1;
+	static int min_count = 8;
+	int expected = -1;
+	int target = segment_id - margin;
+	int fast_seeking;
+	int prev_segment = ft_location.segment;
+	TRACE_FUN(ft_t_flow);
+
+	if (!ft_location.known) {
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "fatal: cannot seek from unknown location");
+	}
+	if (!validate(segment_id)) {
+		ftape_sleep(1 * FT_SECOND);
+		ft_failure = 1;
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "fatal: head off track (bad hardware?)");
+	}
+	TRACE(ft_t_noise, "from %d/%d to %d/0 - %d",
+	      ft_location.segment, ft_location.sector,segment_id,margin);
+	count = target - ft_location.segment - overshoot;
+	fast_seeking = (fast &&
+			count > (min_count + (ft_location.bot ? 1 : 0)));
+	if (fast_seeking) {
+		TRACE(ft_t_noise, "fast skipping %d segments", count);
+		expected = segment_id - margin;
+		fast_seek(count, 0);
+	}
+	if (!ftape_tape_running) {
+		logical_forward();
+	}
+	while (ft_location.segment < segment_id) {
+		/*  This requires at least one sector in a (bad) segment to
+		 *  have a valid and readable sector id !
+		 *  It looks like this is not guaranteed, so we must try
+		 *  to find a way to skip an EMPTY_SEGMENT. !!! FIXME !!!
+		 */
+		if (ftape_read_id() < 0 || !ft_location.known ||
+		    sigtestsetmask(&current->pending.signal, _DONT_BLOCK)) {
+			ft_location.known = 0;
+			if (!ftape_tape_running ||
+			    ++failures > FT_SECTORS_PER_SEGMENT) {
+				TRACE_ABORT(-EIO, ft_t_err,
+					    "read_id failed completely");
+			}
+			FT_SIGNAL_EXIT(_DONT_BLOCK);
+			TRACE(ft_t_flow, "read_id failed, retry (%d)",
+			      failures);
+			continue;
+		}
+		if (fast_seeking) {
+			TRACE(ft_t_noise, "ended at %d/%d (%d,%d)",
+			      ft_location.segment, ft_location.sector,
+			      overshoot, inhibit_correction);
+			if (!inhibit_correction &&
+			    (ft_location.segment < expected ||
+			     ft_location.segment > expected + margin)) {
+				int error = ft_location.segment - expected;
+				TRACE(ft_t_noise,
+				      "adjusting overshoot from %d to %d",
+				      overshoot, overshoot + error);
+				overshoot += error;
+				/*  All overshoots have the same
+				 *  direction, so it should never
+				 *  become negative, but who knows.
+				 */
+				if (overshoot < -5 ||
+				    overshoot > OVERSHOOT_LIMIT) {
+					if (overshoot < 0) {
+						/* keep sane value */
+						overshoot = -5;
+					} else {
+						/* keep sane value */
+						overshoot = OVERSHOOT_LIMIT;
+					}
+					TRACE(ft_t_noise,
+					      "clipped overshoot to %d",
+					      overshoot);
+				}
+			}
+			fast_seeking = 0;
+		}
+		if (ft_location.known) {
+			if (ft_location.segment > prev_segment + 1) {
+				TRACE(ft_t_noise,
+				      "missed segment %d while skipping",
+				      prev_segment + 1);
+			}
+			prev_segment = ft_location.segment;
+		}
+	}
+	if (ft_location.segment > segment_id) {
+		TRACE_ABORT(-EIO,
+			    ft_t_noise, "failed: skip ended at segment %d/%d",
+			    ft_location.segment, ft_location.sector);
+	}
+	TRACE_EXIT 0;
+}
+
+static int skip_reverse(int segment_id, int *pstatus)
+{
+	int failures = 0;
+	static int overshoot = 1;
+	static int min_rewind = 2;	/* 1 + overshoot */
+	static const int margin = 1;	/* stop this before target */
+	int expected = 0;
+	int count = 1;
+	int short_seek;
+	int target = segment_id - margin;
+	TRACE_FUN(ft_t_flow);
+
+	if (ft_location.known && !validate(segment_id)) {
+		ftape_sleep(1 * FT_SECOND);
+		ft_failure = 1;
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "fatal: head off track (bad hardware?)");
+	}
+	do {
+		if (!ft_location.known) {
+			TRACE(ft_t_warn, "warning: location not known");
+		}
+		TRACE(ft_t_noise, "from %d/%d to %d/0 - %d",
+		      ft_location.segment, ft_location.sector,
+		      segment_id, margin);
+		/*  min_rewind == 1 + overshoot_when_doing_minimum_rewind
+		 *  overshoot  == overshoot_when_doing_larger_rewind
+		 *  Initially min_rewind == 1 + overshoot, optimization
+		 *  of both values will be done separately.
+		 *  overshoot and min_rewind can be negative as both are
+		 *  sums of three components:
+		 *  any_overshoot == rewind_overshoot - 
+		 *                   stop_overshoot   -
+		 *                   start_overshoot
+		 */
+		if (ft_location.segment - target - (min_rewind - 1) < 1) {
+			short_seek = 1;
+		} else {
+			count = ft_location.segment - target - overshoot;
+			short_seek = (count < 1);
+		}
+		if (short_seek) {
+			count = 1;	/* do shortest rewind */
+			expected = ft_location.segment - min_rewind;
+			if (expected/ft_segments_per_track != ft_location.track) {
+				expected = (ft_location.track * 
+					    ft_segments_per_track);
+			}
+		} else {
+			expected = target;
+		}
+		fast_seek(count, 1);
+		logical_forward();
+		if (ftape_read_id() < 0 || !ft_location.known ||
+		    (sigtestsetmask(&current->pending.signal, _DONT_BLOCK))) {
+			if ((!ftape_tape_running && !ft_location.known) ||
+			    ++failures > FT_SECTORS_PER_SEGMENT) {
+				TRACE_ABORT(-EIO, ft_t_err,
+					    "read_id failed completely");
+			}
+			FT_SIGNAL_EXIT(_DONT_BLOCK);
+			TRACE_CATCH(ftape_report_drive_status(pstatus),);
+			TRACE(ft_t_noise, "ftape_read_id failed, retry (%d)",
+			      failures);
+			continue;
+		}
+		TRACE(ft_t_noise, "ended at %d/%d (%d,%d,%d)", 
+		      ft_location.segment, ft_location.sector,
+		      min_rewind, overshoot, inhibit_correction);
+		if (!inhibit_correction &&
+		    (ft_location.segment < expected ||
+		     ft_location.segment > expected + margin)) {
+			int error = expected - ft_location.segment;
+			if (short_seek) {
+				TRACE(ft_t_noise,
+				      "adjusting min_rewind from %d to %d",
+				      min_rewind, min_rewind + error);
+				min_rewind += error;
+				if (min_rewind < -5) {
+					/* is this right ? FIXME ! */
+					/* keep sane value */
+					min_rewind = -5;
+					TRACE(ft_t_noise, 
+					      "clipped min_rewind to %d",
+					      min_rewind);
+				}
+			} else {
+				TRACE(ft_t_noise,
+				      "adjusting overshoot from %d to %d",
+				      overshoot, overshoot + error);
+				overshoot += error;
+				if (overshoot < -5 ||
+				    overshoot > OVERSHOOT_LIMIT) {
+					if (overshoot < 0) {
+						/* keep sane value */
+						overshoot = -5;
+					} else {
+						/* keep sane value */
+						overshoot = OVERSHOOT_LIMIT;
+					}
+					TRACE(ft_t_noise,
+					      "clipped overshoot to %d",
+					      overshoot);
+				}
+			}
+		}
+	} while (ft_location.segment > segment_id);
+	if (ft_location.known) {
+		TRACE(ft_t_noise, "current location: %d/%d",
+		      ft_location.segment, ft_location.sector);
+	}
+	TRACE_EXIT 0;
+}
+
+static int determine_position(void)
+{
+	int retry = 0;
+	int status;
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	if (!ftape_tape_running) {
+		/*  This should only happen if tape is stopped by isr.
+		 */
+		TRACE(ft_t_flow, "waiting for tape stop");
+		if (ftape_ready_wait(ftape_timeout.pause, &status) < 0) {
+			TRACE(ft_t_flow, "drive still running (fatal)");
+			ftape_tape_running = 1;	/* ? */
+		}
+	} else {
+		ftape_report_drive_status(&status);
+	}
+	if (status & QIC_STATUS_READY) {
+		/*  Drive must be ready to check error state !
+		 */
+		TRACE(ft_t_flow, "drive is ready");
+		if (status & QIC_STATUS_ERROR) {
+			unsigned int error;
+			qic117_cmd_t command;
+
+			/*  Report and clear error state, try to continue.
+			 */
+			TRACE(ft_t_flow, "error status set");
+			ftape_report_error(&error, &command, 1);
+			ftape_ready_wait(ftape_timeout.reset, &status);
+			ftape_tape_running = 0;	/* ? */
+		}
+		if (check_bot_eot(status)) {
+			if (ft_location.bot) {
+				if ((status & QIC_STATUS_READY) == 0) {
+					/* tape moving away from
+					 * bot/eot, let's see if we
+					 * can catch up with the first
+					 * segment on this track.
+					 */
+				} else {
+					TRACE(ft_t_flow,
+					      "start tape from logical bot");
+					logical_forward();	/* start moving */
+				}
+			} else {
+				if ((status & QIC_STATUS_READY) == 0) {
+					TRACE(ft_t_noise, "waiting for logical end of track");
+					result = ftape_ready_wait(ftape_timeout.reset, &status);
+					/* error handling needed ? */
+				} else {
+					TRACE(ft_t_noise,
+					      "tape at logical end of track");
+				}
+			}
+		} else {
+			TRACE(ft_t_flow, "start tape");
+			logical_forward();	/* start moving */
+			ft_location.known = 0;	/* not cleared by logical forward ! */
+		}
+	}
+	/* tape should be moving now, start reading id's
+	 */
+	while (!ft_location.known &&
+	       retry++ < FT_SECTORS_PER_SEGMENT &&
+	       (result = ftape_read_id()) < 0) {
+
+		TRACE(ft_t_flow, "location unknown");
+
+		/* exit on signal
+		 */
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+
+		/*  read-id somehow failed, tape may
+		 *  have reached end or some other
+		 *  error happened.
+		 */
+		TRACE(ft_t_flow, "read-id failed");
+		TRACE_CATCH(ftape_report_drive_status(&status),);
+		TRACE(ft_t_err, "ftape_report_drive_status: 0x%02x", status);
+		if (status & QIC_STATUS_READY) {
+			ftape_tape_running = 0;
+			TRACE(ft_t_noise, "tape stopped for unknown reason! "
+			      "status = 0x%02x", status);
+			if (status & QIC_STATUS_ERROR ||
+			    !check_bot_eot(status)) {
+				/* oops, tape stopped but not at end!
+				 */
+				TRACE_EXIT -EIO;
+			}
+		}
+	}
+	TRACE(ft_t_flow,
+	      "tape is positioned at segment %d", ft_location.segment);
+	TRACE_EXIT ft_location.known ? 0 : -EIO;
+}
+
+/*      Get the tape running and position it just before the
+ *      requested segment.
+ *      Seek tape-track and reposition as needed.
+ */
+int ftape_start_tape(int segment_id, int sector_offset)
+{
+	int track = segment_id / ft_segments_per_track;
+	int result = -EIO;
+	int status;
+	static int last_segment = -1;
+	static int bad_bus_timing = 0;
+	/* number of segments passing the head between starting the tape
+	 * and being able to access the first sector.
+	 */
+	static int start_offset = 1;
+	int retry;
+	TRACE_FUN(ft_t_flow);
+
+	/* If sector_offset > 0, seek into wanted segment instead of
+	 * into previous.
+	 * This allows error recovery if a part of the segment is bad
+	 * (erased) causing the tape drive to generate an index pulse
+	 * thus causing a no-data error before the requested sector
+	 * is reached.
+	 */
+	ftape_tape_running = 0;
+	TRACE(ft_t_noise, "target segment: %d/%d%s", segment_id, sector_offset,
+		ft_buffer[ft_head]->retry > 0 ? " retry" : "");
+	if (ft_buffer[ft_head]->retry > 0) {	/* this is a retry */
+		int dist = segment_id - last_segment;
+
+		if ((int)ft_history.overrun_errors < overrun_count_offset) {
+			overrun_count_offset = ft_history.overrun_errors;
+		} else if (dist < 0 || dist > 50) {
+			overrun_count_offset = ft_history.overrun_errors;
+		} else if ((ft_history.overrun_errors -
+			    overrun_count_offset) >= 8) {
+			if (ftape_increase_threshold() >= 0) {
+				--ft_buffer[ft_head]->retry;
+				overrun_count_offset =
+					ft_history.overrun_errors;
+				TRACE(ft_t_warn, "increased threshold because "
+				      "of excessive overrun errors");
+			} else if (!bad_bus_timing && ft_data_rate >= 1000) {
+				ftape_half_data_rate();
+				--ft_buffer[ft_head]->retry;
+				bad_bus_timing = 1;
+				overrun_count_offset =
+					ft_history.overrun_errors;
+				TRACE(ft_t_warn, "reduced datarate because "
+				      "of excessive overrun errors");
+			}
+		}
+	}
+	last_segment = segment_id;
+	if (ft_location.track != track ||
+	    (ftape_might_be_off_track && ft_buffer[ft_head]->retry== 0)) {
+		/* current track unknown or not equal to destination
+		 */
+		ftape_ready_wait(ftape_timeout.seek, &status);
+		ftape_seek_head_to_track(track);
+		/* overrun_count_offset = ft_history.overrun_errors; */
+	}
+	result = -EIO;
+	retry = 0;
+	while (result < 0     &&
+	       retry++ <= 5   &&
+	       !ft_failure &&
+	       !(sigtestsetmask(&current->pending.signal, _DONT_BLOCK))) {
+		
+		if (retry && start_offset < 5) {
+			start_offset ++;
+		}
+		/*  Check if we are able to catch the requested
+		 *  segment in time.
+		 */
+		if ((ft_location.known || (determine_position() == 0)) &&
+		    ft_location.segment >=
+		    (segment_id -
+		     ((ftape_tape_running || ft_location.bot)
+		      ? 0 : start_offset))) {
+			/*  Too far ahead (in or past target segment).
+			 */
+			if (ftape_tape_running) {
+				if ((result = ftape_stop_tape(&status)) < 0) {
+					TRACE(ft_t_err,
+					      "stop tape failed with code %d",
+					      result);
+					break;
+				}
+				TRACE(ft_t_noise, "tape stopped");
+				ftape_tape_running = 0;
+			}
+			TRACE(ft_t_noise, "repositioning");
+			++ft_history.rewinds;
+			if (segment_id % ft_segments_per_track < start_offset){
+				TRACE(ft_t_noise, "end of track condition\n"
+				      KERN_INFO "segment_id        : %d\n"
+				      KERN_INFO "ft_segments_per_track: %d\n"
+				      KERN_INFO "start_offset      : %d",
+				      segment_id, ft_segments_per_track, 
+				      start_offset);
+				      
+				/*  If seeking to first segments on
+				 *  track better do a complete rewind
+				 *  to logical begin of track to get a
+				 *  more steady tape motion.  
+				 */
+				result = ftape_command_wait(
+					(ft_location.track & 1)
+					? QIC_PHYSICAL_FORWARD
+					: QIC_PHYSICAL_REVERSE,
+					ftape_timeout.rewind, &status);
+				check_bot_eot(status);	/* update location */
+			} else {
+				result= skip_reverse(segment_id - start_offset,
+						     &status);
+			}
+		}
+		if (!ft_location.known) {
+			TRACE(ft_t_bug, "panic: location not known");
+			result = -EIO;
+			continue; /* while() will check for failure */
+		}
+		TRACE(ft_t_noise, "current segment: %d/%d",
+		      ft_location.segment, ft_location.sector);
+		/*  We're on the right track somewhere before the
+		 *  wanted segment.  Start tape movement if needed and
+		 *  skip to just before or inside the requested
+		 *  segment. Keep tape running.  
+		 */
+		result = 0;
+		if (ft_location.segment < 
+		    (segment_id - ((ftape_tape_running || ft_location.bot)
+				   ? 0 : start_offset))) {
+			if (sector_offset > 0) {
+				result = seek_forward(segment_id,
+						      retry <= 3);
+			} else {
+				result = seek_forward(segment_id - 1,
+						      retry <= 3);
+			}
+		}
+		if (result == 0 &&
+		    ft_location.segment !=
+		    (segment_id - (sector_offset > 0 ? 0 : 1))) {
+			result = -EIO;
+		}
+	}
+	if (result < 0) {
+		TRACE(ft_t_err, "failed to reposition");
+	} else {
+		ft_runner_status = running;
+	}
+	TRACE_EXIT result;
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-rw.h b/drivers/char/ftape/lowlevel/ftape-rw.h
new file mode 100644
index 0000000..32f4fee
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-rw.h
@@ -0,0 +1,111 @@
+#ifndef _FTAPE_RW_H
+#define _FTAPE_RW_H
+
+/*
+ * Copyright (C) 1993-1996 Bas Laarhoven,
+ *           (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-rw.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:25 $
+ *
+ *      This file contains the definitions for the read and write
+ *      functions for the QIC-117 floppy-tape driver for Linux.
+ *
+ * Claus-Justus Heine (1996/09/20): Add definition of format code 6
+ * Claus-Justus Heine (1996/10/04): Changed GET/PUT macros to cast to (__u8 *)
+ *
+ */
+
+#include "../lowlevel/fdc-io.h"
+#include "../lowlevel/ftape-init.h"
+#include "../lowlevel/ftape-bsm.h"
+
+#include <asm/unaligned.h>
+
+#define GET2(address, offset) get_unaligned((__u16*)((__u8 *)address + offset))
+#define GET4(address, offset) get_unaligned((__u32*)((__u8 *)address + offset))
+#define GET8(address, offset) get_unaligned((__u64*)((__u8 *)address + offset))
+#define PUT2(address, offset , value) put_unaligned((value), (__u16*)((__u8 *)address + offset))
+#define PUT4(address, offset , value) put_unaligned((value), (__u32*)((__u8 *)address + offset))
+#define PUT8(address, offset , value) put_unaligned((value), (__u64*)((__u8 *)address + offset))
+
+enum runner_status_enum {
+	idle = 0,
+	running,
+	do_abort,
+	aborting,
+	logical_eot,
+	end_of_tape,
+};
+
+typedef enum ft_buffer_queue {
+	ft_queue_head = 0,
+	ft_queue_tail = 1
+} ft_buffer_queue_t;
+
+
+typedef struct {
+	int track;		/* tape head position */
+	volatile int segment;	/* current segment */
+	volatile int sector;	/* sector offset within current segment */
+	volatile unsigned int bot;	/* logical begin of track */
+	volatile unsigned int eot;	/* logical end of track */
+	volatile unsigned int known;	/* validates bot, segment, sector */
+} location_record;
+
+/*      Count nr of 1's in pattern.
+ */
+static inline int count_ones(unsigned long mask)
+{
+	int bits;
+
+	for (bits = 0; mask != 0; mask >>= 1) {
+		if (mask & 1) {
+			++bits;
+		}
+	}
+	return bits;
+}
+
+#define FT_MAX_NR_BUFFERS 16 /* arbitrary value */
+/*      ftape-rw.c defined global vars.
+ */
+extern buffer_struct *ft_buffer[FT_MAX_NR_BUFFERS];
+extern int ft_nr_buffers;
+extern location_record ft_location;
+extern volatile int ftape_tape_running;
+
+/*      ftape-rw.c defined global functions.
+ */
+extern int  ftape_setup_new_segment(buffer_struct * buff,
+				    int segment_id,
+				    int offset);
+extern int  ftape_calc_next_cluster(buffer_struct * buff);
+extern buffer_struct *ftape_next_buffer (ft_buffer_queue_t pos);
+extern buffer_struct *ftape_get_buffer  (ft_buffer_queue_t pos);
+extern int            ftape_buffer_id   (ft_buffer_queue_t pos);
+extern void           ftape_reset_buffer(void);
+extern void ftape_tape_parameters(__u8 drive_configuration);
+extern int  ftape_wait_segment(buffer_state_enum state);
+extern int  ftape_dumb_stop(void);
+extern int  ftape_start_tape(int segment_id, int offset);
+extern int  ftape_stop_tape(int *pstatus);
+extern int  ftape_handle_logical_eot(void);
+extern buffer_state_enum ftape_set_state(buffer_state_enum new_state);
+#endif				/* _FTAPE_RW_H */
diff --git a/drivers/char/ftape/lowlevel/ftape-setup.c b/drivers/char/ftape/lowlevel/ftape-setup.c
new file mode 100644
index 0000000..280a1a5
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-setup.c
@@ -0,0 +1,105 @@
+/* 
+ * Copyright (C) 1996, 1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-setup.c,v $
+ * $Revision: 1.7 $
+ * $Date: 1997/10/10 09:57:06 $
+ *
+ *      This file contains the code for processing the kernel command
+ *      line options for the QIC-40/80/3010/3020 floppy-tape driver
+ *      "ftape" for Linux.
+ */
+
+#include <linux/config.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+
+#include <linux/ftape.h>
+#include <linux/init.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/fdc-io.h"
+
+static struct param_table {
+	const char *name;
+	int *var;
+	int def_param;
+	int min;
+	int max;
+} config_params[] __initdata = {
+#ifndef CONFIG_FT_NO_TRACE_AT_ALL
+	{ "tracing",   &ftape_tracing,     3,              ft_t_bug, ft_t_any},
+#endif
+	{ "ioport",    &ft_fdc_base,       CONFIG_FT_FDC_BASE,     0x0, 0xfff},
+	{ "irq",       &ft_fdc_irq,        CONFIG_FT_FDC_IRQ,        2,    15},
+	{ "dma",       &ft_fdc_dma,        CONFIG_FT_FDC_DMA,        0,     3},
+	{ "threshold", &ft_fdc_threshold,  CONFIG_FT_FDC_THR,         1,    16},
+	{ "datarate",  &ft_fdc_rate_limit, CONFIG_FT_FDC_MAX_RATE, 500,  2000},
+	{ "fc10",      &ft_probe_fc10,     CONFIG_FT_PROBE_FC10,     0,     1},
+	{ "mach2",     &ft_mach2,          CONFIG_FT_MACH2,          0,     1}
+};
+
+static int __init ftape_setup(char *str)
+{
+	int i;
+	int param;
+	int ints[2];
+
+	TRACE_FUN(ft_t_flow);
+
+	str = get_options(str, ARRAY_SIZE(ints), ints);
+	if (str) {
+		for (i=0; i < NR_ITEMS(config_params); i++) {
+			if (strcmp(str,config_params[i].name) == 0){
+				if (ints[0]) {
+					param = ints[1];
+				} else {
+					param = config_params[i].def_param;
+				}
+				if (param < config_params[i].min ||
+				    param > config_params[i].max) {
+					TRACE(ft_t_err,
+					"parameter %s out of range %d ... %d",
+					      config_params[i].name,
+					      config_params[i].min,
+					      config_params[i].max);
+					goto out;
+				}
+				if(config_params[i].var) {
+					TRACE(ft_t_info, "%s=%d", str, param);
+					*config_params[i].var = param;
+				}
+				goto out;
+			}
+		}
+	}
+	if (str) {
+		TRACE(ft_t_err, "unknown ftape option [%s]", str);
+		
+		TRACE(ft_t_err, "allowed options are:");
+		for (i=0; i < NR_ITEMS(config_params); i++) {
+			TRACE(ft_t_err, " %s",config_params[i].name);
+		}
+	} else {
+		TRACE(ft_t_err, "botched ftape option");
+	}
+ out:
+	TRACE_EXIT 1;
+}
+
+__setup("ftape=", ftape_setup);
diff --git a/drivers/char/ftape/lowlevel/ftape-tracing.c b/drivers/char/ftape/lowlevel/ftape-tracing.c
new file mode 100644
index 0000000..7fdc656
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-tracing.c
@@ -0,0 +1,118 @@
+/*
+ *      Copyright (C) 1993-1996 Bas Laarhoven,
+ *                (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-tracing.c,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:27 $
+ *
+ *      This file contains the reading code
+ *      for the QIC-117 floppy-tape driver for Linux.
+ */
+
+#include <linux/ftape.h>
+#include "../lowlevel/ftape-tracing.h"
+
+/*      Global vars.
+ */
+/*      tracing
+ *      set it to:     to log :
+ *       0              bugs
+ *       1              + errors
+ *       2              + warnings
+ *       3              + information
+ *       4              + more information
+ *       5              + program flow
+ *       6              + fdc/dma info
+ *       7              + data flow
+ *       8              + everything else
+ */
+ft_trace_t ftape_tracing = ft_t_info; /* Default level: information and up */
+int  ftape_function_nest_level;
+
+/*      Local vars.
+ */
+static __u8 trace_id;
+static char spacing[] = "*                              ";
+
+void ftape_trace_call(const char *file, const char *name)
+{
+	char *indent;
+
+	/*    Since printk seems not to work with "%*s" format
+	 *    we'll use this work-around.
+	 */
+	if (ftape_function_nest_level < 0) {
+		printk(KERN_INFO "function nest level (%d) < 0\n",
+		       ftape_function_nest_level);
+		ftape_function_nest_level = 0;
+	}
+	if (ftape_function_nest_level < sizeof(spacing)) {
+		indent = (spacing +
+			  sizeof(spacing) - 1 -
+			  ftape_function_nest_level);
+	} else {
+		indent = spacing;
+	}
+	printk(KERN_INFO "[%03d]%s+%s (%s)\n",
+	       (int) trace_id++, indent, file, name);
+}
+
+void ftape_trace_exit(const char *file, const char *name)
+{
+	char *indent;
+
+	/*    Since printk seems not to work with "%*s" format
+	 *    we'll use this work-around.
+	 */
+	if (ftape_function_nest_level < 0) {
+		printk(KERN_INFO "function nest level (%d) < 0\n", ftape_function_nest_level);
+		ftape_function_nest_level = 0;
+	}
+	if (ftape_function_nest_level < sizeof(spacing)) {
+		indent = (spacing +
+			  sizeof(spacing) - 1 -
+			  ftape_function_nest_level);
+	} else {
+		indent = spacing;
+	}
+	printk(KERN_INFO "[%03d]%s-%s (%s)\n",
+	       (int) trace_id++, indent, file, name);
+}
+
+void ftape_trace_log(const char *file, const char *function)
+{
+	char *indent;
+
+	/*    Since printk seems not to work with "%*s" format
+	 *    we'll use this work-around.
+	 */
+	if (ftape_function_nest_level < 0) {
+		printk(KERN_INFO "function nest level (%d) < 0\n", ftape_function_nest_level);
+		ftape_function_nest_level = 0;
+	}
+	if (ftape_function_nest_level < sizeof(spacing)) {
+		indent = (spacing + 
+			  sizeof(spacing) - 1 - 
+			  ftape_function_nest_level);
+	} else {
+		indent = spacing;
+	}
+	printk(KERN_INFO "[%03d]%s%s (%s) - ", 
+	       (int) trace_id++, indent, file, function);
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-tracing.h b/drivers/char/ftape/lowlevel/ftape-tracing.h
new file mode 100644
index 0000000..fa7cd20
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-tracing.h
@@ -0,0 +1,180 @@
+#ifndef _FTAPE_TRACING_H
+#define _FTAPE_TRACING_H
+
+/*
+ * Copyright (C) 1994-1996 Bas Laarhoven,
+ *           (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-tracing.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:28 $
+ *
+ *      This file contains definitions that eases the debugging of the
+ *      QIC-40/80/3010/3020 floppy-tape driver "ftape" for Linux.
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+
+/*
+ *  Be very careful with TRACE_EXIT and TRACE_ABORT.
+ *
+ *  if (something) TRACE_EXIT error;
+ *
+ *  will NOT work. Use
+ *
+ *  if (something) {
+ *    TRACE_EXIT error;
+ *  }
+ *
+ *  instead. Maybe a bit dangerous, but save lots of lines of code.
+ */
+
+#define LL_X "%d/%d KB"
+#define LL(x) (unsigned int)((__u64)(x)>>10), (unsigned int)((x)&1023)
+
+typedef enum {
+	ft_t_nil = -1,
+	ft_t_bug,
+	ft_t_err,
+	ft_t_warn,
+	ft_t_info,
+	ft_t_noise,
+	ft_t_flow,
+	ft_t_fdc_dma,
+	ft_t_data_flow,
+	ft_t_any
+} ft_trace_t;
+
+#ifdef  CONFIG_FT_NO_TRACE_AT_ALL
+/*  the compiler will optimize away most TRACE() macros
+ */
+#define FT_TRACE_TOP_LEVEL	ft_t_bug
+#define TRACE_FUN(level)	do {} while(0)
+#define TRACE_EXIT		return
+#define TRACE(l, m, i...)						\
+{									\
+	if ((ft_trace_t)(l) == FT_TRACE_TOP_LEVEL) {			\
+		printk(KERN_INFO"ftape%s(%s):\n"	                \
+		       KERN_INFO m".\n" ,__FILE__, __FUNCTION__ , ##i);	\
+	}								\
+}
+#define SET_TRACE_LEVEL(l)      if ((l) == (l)) do {} while(0)
+#define TRACE_LEVEL		FT_TRACE_TOP_LEVEL
+
+#else
+
+#ifdef CONFIG_FT_NO_TRACE
+/*  the compiler will optimize away many TRACE() macros
+ *  the ftape_simple_trace_call() function simply increments 
+ *  the function nest level.
+ */ 
+#define FT_TRACE_TOP_LEVEL	ft_t_warn
+#define TRACE_FUN(level)	ftape_function_nest_level++
+#define TRACE_EXIT		ftape_function_nest_level--; return
+
+#else
+#ifdef CONFIG_FT_FULL_DEBUG
+#define FT_TRACE_TOP_LEVEL ft_t_any
+#else
+#define FT_TRACE_TOP_LEVEL ft_t_flow
+#endif
+#define TRACE_FUN(level)					\
+	const ft_trace_t _tracing = level;			\
+	if (ftape_tracing >= (ft_trace_t)(level) &&		\
+	    (ft_trace_t)(level) <= FT_TRACE_TOP_LEVEL)		\
+		ftape_trace_call(__FILE__, __FUNCTION__);	\
+	ftape_function_nest_level ++;
+
+#define TRACE_EXIT						\
+	--ftape_function_nest_level;				\
+	if (ftape_tracing >= (ft_trace_t)(_tracing) &&		\
+	    (ft_trace_t)(_tracing) <= FT_TRACE_TOP_LEVEL)	\
+		ftape_trace_exit(__FILE__, __FUNCTION__);	\
+	return
+
+#endif
+
+#define TRACE(l, m, i...)					\
+{								\
+	if (ftape_tracing >= (ft_trace_t)(l) &&			\
+	    (ft_trace_t)(l) <= FT_TRACE_TOP_LEVEL) {		\
+		ftape_trace_log(__FILE__, __FUNCTION__);	\
+		printk(m".\n" ,##i);				\
+	}							\
+}
+
+#define SET_TRACE_LEVEL(l) 				\
+{							\
+	if ((ft_trace_t)(l) <= FT_TRACE_TOP_LEVEL) {	\
+		ftape_tracing = (ft_trace_t)(l);	\
+	} else {					\
+		ftape_tracing = FT_TRACE_TOP_LEVEL;	\
+	}						\
+}
+#define TRACE_LEVEL    							     \
+((ftape_tracing <= FT_TRACE_TOP_LEVEL) ? ftape_tracing : FT_TRACE_TOP_LEVEL)
+
+
+/*      Global variables declared in tracing.c
+ */
+extern ft_trace_t ftape_tracing;  /* sets default level */
+extern int ftape_function_nest_level;
+
+/*      Global functions declared in tracing.c
+ */
+extern void ftape_trace_call(const char *file, const char *name);
+extern void ftape_trace_exit(const char *file, const char *name);
+extern void ftape_trace_log (const char *file, const char *name);
+
+#endif /* !defined(CONFIG_FT_NO_TRACE_AT_ALL) */
+
+/*
+ *   Abort with a message.
+ */
+#define TRACE_ABORT(res, i...)			\
+{						\
+ 	TRACE(i);				\
+	TRACE_EXIT res;				\
+}
+
+/*   The following transforms the common "if(result < 0) ... " into a
+ *   one-liner.
+ */
+#define _TRACE_CATCH(level, fun, action)				\
+{									\
+	int _res = (fun);						\
+	if (_res < 0) {							\
+		do { action /* */ ; } while(0);				\
+		TRACE_ABORT(_res, level, "%s failed: %d", #fun,	_res);	\
+	}								\
+}
+
+#define TRACE_CATCH(fun, fail) _TRACE_CATCH(ft_t_err, fun, fail)
+
+/*  Abort the current function when signalled. This doesn't belong here,
+ *  but rather into ftape-rw.h (maybe)
+ */
+#define FT_SIGNAL_EXIT(sig_mask)					\
+	if (sigtestsetmask(&current->pending.signal, sig_mask)) {	\
+		TRACE_ABORT(-EINTR,					\
+			    ft_t_warn,					\
+			    "interrupted by non-blockable signal");	\
+	}
+
+#endif /* _FTAPE_TRACING_H */
diff --git a/drivers/char/ftape/lowlevel/ftape-write.c b/drivers/char/ftape/lowlevel/ftape-write.c
new file mode 100644
index 0000000..45601ec
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-write.c
@@ -0,0 +1,336 @@
+/*
+ *      Copyright (C) 1993-1995 Bas Laarhoven,
+ *                (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-write.c,v $
+ * $Revision: 1.3.4.1 $
+ * $Date: 1997/11/14 18:07:04 $
+ *
+ *      This file contains the writing code
+ *      for the QIC-117 floppy-tape driver for Linux.
+ */
+
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+
+#include <linux/ftape.h>
+#include <linux/qic117.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-write.h"
+#include "../lowlevel/ftape-read.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-ecc.h"
+#include "../lowlevel/ftape-bsm.h"
+#include "../lowlevel/fdc-isr.h"
+
+/*      Global vars.
+ */
+
+/*      Local vars.
+ */
+static int last_write_failed;
+
+void ftape_zap_write_buffers(void)
+{
+	int i;
+
+	for (i = 0; i < ft_nr_buffers; ++i) {
+		ft_buffer[i]->status = done;
+	}
+	ftape_reset_buffer();
+}
+
+static int copy_and_gen_ecc(void *destination, 
+			    const void *source,
+			    const SectorMap bad_sector_map)
+{
+	int result;
+	struct memory_segment mseg;
+	int bads = count_ones(bad_sector_map);
+	TRACE_FUN(ft_t_any);
+
+	if (bads > 0) {
+		TRACE(ft_t_noise, "bad sectors in map: %d", bads);
+	}
+	if (bads + 3 >= FT_SECTORS_PER_SEGMENT) {
+		TRACE(ft_t_noise, "empty segment");
+		mseg.blocks = 0; /* skip entire segment */
+		result = 0;      /* nothing written */
+	} else {
+		mseg.blocks = FT_SECTORS_PER_SEGMENT - bads;
+		mseg.data = destination;
+		memcpy(mseg.data, source, (mseg.blocks - 3) * FT_SECTOR_SIZE);
+		result = ftape_ecc_set_segment_parity(&mseg);
+		if (result < 0) {
+			TRACE(ft_t_err, "ecc_set_segment_parity failed");
+		} else {
+			result = (mseg.blocks - 3) * FT_SECTOR_SIZE;
+		}
+	}
+	TRACE_EXIT result;
+}
+
+
+int ftape_start_writing(const ft_write_mode_t mode)
+{
+	buffer_struct *head = ftape_get_buffer(ft_queue_head);
+	int segment_id = head->segment_id;
+	int result;
+	buffer_state_enum wanted_state = (mode == FT_WR_DELETE
+					  ? deleting
+					  : writing);
+	TRACE_FUN(ft_t_flow);
+
+	if ((ft_driver_state != wanted_state) || head->status != waiting) {
+		TRACE_EXIT 0;
+	}
+	ftape_setup_new_segment(head, segment_id, 1);
+	if (mode == FT_WR_SINGLE) {
+		/* stop tape instead of pause */
+		head->next_segment = 0;
+	}
+	ftape_calc_next_cluster(head); /* prepare */
+	head->status = ft_driver_state; /* either writing or deleting */
+	if (ft_runner_status == idle) {
+		TRACE(ft_t_noise,
+		      "starting runner for segment %d", segment_id);
+		TRACE_CATCH(ftape_start_tape(segment_id,head->sector_offset),);
+	} else {
+		TRACE(ft_t_noise, "runner not idle, not starting tape");
+	}
+	/* go */
+	result = fdc_setup_read_write(head, (mode == FT_WR_DELETE
+					     ? FDC_WRITE_DELETED : FDC_WRITE));
+	ftape_set_state(wanted_state); /* should not be necessary */
+	TRACE_EXIT result;
+}
+
+/*  Wait until all data is actually written to tape.
+ *  
+ *  There is a problem: when the tape runs into logical EOT, then this
+ *  failes. We need to restart the runner in this case.
+ */
+int ftape_loop_until_writes_done(void)
+{
+	buffer_struct *head;
+	TRACE_FUN(ft_t_flow);
+
+	while ((ft_driver_state == writing || ft_driver_state == deleting) && 
+	       ftape_get_buffer(ft_queue_head)->status != done) {
+		/* set the runner status to idle if at lEOT */
+		TRACE_CATCH(ftape_handle_logical_eot(),	last_write_failed = 1);
+		/* restart the tape if necessary */
+		if (ft_runner_status == idle) {
+			TRACE(ft_t_noise, "runner is idle, restarting");
+			if (ft_driver_state == deleting) {
+				TRACE_CATCH(ftape_start_writing(FT_WR_DELETE),
+					    last_write_failed = 1);
+			} else {
+				TRACE_CATCH(ftape_start_writing(FT_WR_MULTI),
+					    last_write_failed = 1);
+			}
+		}
+		TRACE(ft_t_noise, "tail: %d, head: %d", 
+		      ftape_buffer_id(ft_queue_tail),
+		      ftape_buffer_id(ft_queue_head));
+		TRACE_CATCH(fdc_interrupt_wait(5 * FT_SECOND),
+			    last_write_failed = 1);
+		head = ftape_get_buffer(ft_queue_head);
+		if (head->status == error) {
+			/* Allow escape from loop when signaled !
+			 */
+			FT_SIGNAL_EXIT(_DONT_BLOCK);
+			if (head->hard_error_map != 0) {
+				/*  Implement hard write error recovery here
+				 */
+			}
+			/* retry this one */
+			head->status = waiting;
+			if (ft_runner_status == aborting) {
+				ftape_dumb_stop();
+			}
+			if (ft_runner_status != idle) {
+				TRACE_ABORT(-EIO, ft_t_err,
+					    "unexpected state: "
+					    "ft_runner_status != idle");
+			}
+			ftape_start_writing(ft_driver_state == deleting
+					    ? FT_WR_MULTI : FT_WR_DELETE);
+		}
+		TRACE(ft_t_noise, "looping until writes done");
+	}
+	ftape_set_state(idle);
+	TRACE_EXIT 0;
+}
+
+/*      Write given segment from buffer at address to tape.
+ */
+static int write_segment(const int segment_id,
+			 const void *address, 
+			 const ft_write_mode_t write_mode)
+{
+	int bytes_written = 0;
+	buffer_struct *tail;
+	buffer_state_enum wanted_state = (write_mode == FT_WR_DELETE
+					  ? deleting : writing);
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_noise, "segment_id = %d", segment_id);
+	if (ft_driver_state != wanted_state) {
+		if (ft_driver_state == deleting ||
+		    wanted_state == deleting) {
+			TRACE_CATCH(ftape_loop_until_writes_done(),);
+		}
+		TRACE(ft_t_noise, "calling ftape_abort_operation");
+		TRACE_CATCH(ftape_abort_operation(),);
+		ftape_zap_write_buffers();
+		ftape_set_state(wanted_state);
+	}
+	/*    if all buffers full we'll have to wait...
+	 */
+	ftape_wait_segment(wanted_state);
+	tail = ftape_get_buffer(ft_queue_tail);
+	switch(tail->status) {
+	case done:
+		ft_history.defects += count_ones(tail->hard_error_map);
+		break;
+	case waiting:
+		/* this could happen with multiple EMPTY_SEGMENTs, but
+		 * shouldn't happen any more as we re-start the runner even
+		 * with an empty segment.
+		 */
+		bytes_written = -EAGAIN;
+		break;
+	case error:
+		/*  setup for a retry
+		 */
+		tail->status = waiting;
+		bytes_written = -EAGAIN; /* force retry */
+		if (tail->hard_error_map != 0) {
+			TRACE(ft_t_warn, 
+			      "warning: %d hard error(s) in written segment",
+			      count_ones(tail->hard_error_map));
+			TRACE(ft_t_noise, "hard_error_map = 0x%08lx", 
+			      (long)tail->hard_error_map);
+			/*  Implement hard write error recovery here
+			 */
+		}
+		break;
+	default:
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "wait for empty segment failed, tail status: %d",
+			    tail->status);
+	}
+	/*    should runner stop ?
+	 */
+	if (ft_runner_status == aborting) {
+		buffer_struct *head = ftape_get_buffer(ft_queue_head);
+		if (head->status == wanted_state) {
+			head->status = done; /* ???? */
+		}
+		/*  don't call abort_operation(), we don't want to zap
+		 *  the dma buffers
+		 */
+		TRACE_CATCH(ftape_dumb_stop(),);
+	} else {
+		/*  If just passed last segment on tape: wait for BOT
+		 *  or EOT mark. Sets ft_runner_status to idle if at lEOT
+		 *  and successful 
+		 */
+		TRACE_CATCH(ftape_handle_logical_eot(),);
+	}
+	if (tail->status == done) {
+		/* now at least one buffer is empty, fill it with our
+		 * data.  skip bad sectors and generate ecc.
+		 * copy_and_gen_ecc return nr of bytes written, range
+		 * 0..29 Kb inclusive!  
+		 *
+		 * Empty segments are handled inside coyp_and_gen_ecc()
+		 */
+		if (write_mode != FT_WR_DELETE) {
+			TRACE_CATCH(bytes_written = copy_and_gen_ecc(
+				tail->address, address,
+				ftape_get_bad_sector_entry(segment_id)),);
+		}
+		tail->segment_id = segment_id;
+		tail->status = waiting;
+		tail = ftape_next_buffer(ft_queue_tail);
+	}
+	/*  Start tape only if all buffers full or flush mode.
+	 *  This will give higher probability of streaming.
+	 */
+	if (ft_runner_status != running && 
+	    ((tail->status == waiting &&
+	      ftape_get_buffer(ft_queue_head) == tail) ||
+	     write_mode != FT_WR_ASYNC)) {
+		TRACE_CATCH(ftape_start_writing(write_mode),);
+	}
+	TRACE_EXIT bytes_written;
+}
+
+/*  Write as much as fits from buffer to the given segment on tape
+ *  and handle retries.
+ *  Return the number of bytes written (>= 0), or:
+ *      -EIO          write failed
+ *      -EINTR        interrupted by signal
+ *      -ENOSPC       device full
+ */
+int ftape_write_segment(const int segment_id,
+			const void *buffer, 
+			const ft_write_mode_t flush)
+{
+	int retry = 0;
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	ft_history.used |= 2;
+	if (segment_id >= ft_tracks_per_tape*ft_segments_per_track) {
+		/* tape full */
+		TRACE_ABORT(-ENOSPC, ft_t_err,
+			    "invalid segment id: %d (max %d)", 
+			    segment_id, 
+			    ft_tracks_per_tape * ft_segments_per_track -1);
+	}
+	for (;;) {
+		if ((result = write_segment(segment_id, buffer, flush)) >= 0) {
+			if (result == 0) { /* empty segment */
+				TRACE(ft_t_noise,
+				      "empty segment, nothing written");
+			}
+			TRACE_EXIT result;
+		}
+		if (result == -EAGAIN) {
+			if (++retry > 100) { /* give up */
+				TRACE_ABORT(-EIO, ft_t_err,
+				      "write failed, >100 retries in segment");
+			}
+			TRACE(ft_t_warn, "write error, retry %d (%d)",
+			      retry,
+			      ftape_get_buffer(ft_queue_tail)->segment_id);
+		} else {
+			TRACE_ABORT(result, ft_t_err,
+				    "write_segment failed, error: %d", result);
+		}
+		/* Allow escape from loop when signaled !
+		 */
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+	}
+}
diff --git a/drivers/char/ftape/lowlevel/ftape-write.h b/drivers/char/ftape/lowlevel/ftape-write.h
new file mode 100644
index 0000000..0e7f898
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape-write.h
@@ -0,0 +1,53 @@
+#ifndef _FTAPE_WRITE_H
+#define _FTAPE_WRITE_H
+
+/*
+ * Copyright (C) 1994-1995 Bas Laarhoven,
+ *           (C) 1996-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape-write.h,v $
+ $Author: claus $
+ *
+ $Revision: 1.2 $
+ $Date: 1997/10/05 19:18:30 $
+ $State: Exp $
+ *
+ *      This file contains the definitions for the write functions
+ *      for the QIC-117 floppy-tape driver for Linux.
+ *
+ */
+
+
+/*      ftape-write.c defined global functions.
+ */
+typedef enum {
+	FT_WR_ASYNC  = 0, /* start tape only when all buffers are full */
+	FT_WR_MULTI  = 1, /* start tape, but don't necessarily stop */
+	FT_WR_SINGLE = 2, /* write a single segment and stop afterwards */
+	FT_WR_DELETE = 3  /* write deleted data marks */
+} ft_write_mode_t;
+
+extern int  ftape_start_writing(const ft_write_mode_t mode);
+extern int  ftape_write_segment(const int segment,
+				const void *address, 
+				const ft_write_mode_t flushing);
+extern void ftape_zap_write_buffers(void);
+extern int  ftape_loop_until_writes_done(void);
+
+#endif				/* _FTAPE_WRITE_H */
+
diff --git a/drivers/char/ftape/lowlevel/ftape_syms.c b/drivers/char/ftape/lowlevel/ftape_syms.c
new file mode 100644
index 0000000..5dc3a38
--- /dev/null
+++ b/drivers/char/ftape/lowlevel/ftape_syms.c
@@ -0,0 +1,88 @@
+/*
+ *      Copyright (C) 1996-1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/lowlevel/ftape_syms.c,v $
+ * $Revision: 1.4 $
+ * $Date: 1997/10/17 00:03:51 $
+ *
+ *      This file contains the symbols that the ftape low level
+ *      part of the QIC-40/80/3010/3020 floppy-tape driver "ftape"
+ *      exports to its high level clients
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include <linux/ftape.h>
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-init.h"
+#include "../lowlevel/fdc-io.h"
+#include "../lowlevel/ftape-read.h"
+#include "../lowlevel/ftape-write.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-rw.h"
+#include "../lowlevel/ftape-bsm.h"
+#include "../lowlevel/ftape-buffer.h"
+#include "../lowlevel/ftape-format.h"
+
+/* bad sector handling from ftape-bsm.c */
+EXPORT_SYMBOL(ftape_get_bad_sector_entry);
+EXPORT_SYMBOL(ftape_find_end_of_bsm_list);
+/* from ftape-rw.c */
+EXPORT_SYMBOL(ftape_set_state);
+/* from ftape-ctl.c */
+EXPORT_SYMBOL(ftape_seek_to_bot);
+EXPORT_SYMBOL(ftape_seek_to_eot);
+EXPORT_SYMBOL(ftape_abort_operation);
+EXPORT_SYMBOL(ftape_get_status);
+EXPORT_SYMBOL(ftape_enable);
+EXPORT_SYMBOL(ftape_disable);
+EXPORT_SYMBOL(ftape_mmap);
+EXPORT_SYMBOL(ftape_calibrate_data_rate);
+/* from ftape-io.c */
+EXPORT_SYMBOL(ftape_reset_drive);
+EXPORT_SYMBOL(ftape_command);
+EXPORT_SYMBOL(ftape_parameter);
+EXPORT_SYMBOL(ftape_ready_wait);
+EXPORT_SYMBOL(ftape_report_operation);
+EXPORT_SYMBOL(ftape_report_error);
+/* from ftape-read.c */
+EXPORT_SYMBOL(ftape_read_segment_fraction);
+EXPORT_SYMBOL(ftape_zap_read_buffers);
+EXPORT_SYMBOL(ftape_read_header_segment);
+EXPORT_SYMBOL(ftape_decode_header_segment);
+/* from ftape-write.c */
+EXPORT_SYMBOL(ftape_write_segment);
+EXPORT_SYMBOL(ftape_start_writing);
+EXPORT_SYMBOL(ftape_loop_until_writes_done);
+/* from ftape-buffer.h */
+EXPORT_SYMBOL(ftape_set_nr_buffers);
+/* from ftape-format.h */
+EXPORT_SYMBOL(ftape_format_track);
+EXPORT_SYMBOL(ftape_format_status);
+EXPORT_SYMBOL(ftape_verify_segment);
+/* from tracing.c */
+#ifndef CONFIG_FT_NO_TRACE_AT_ALL
+EXPORT_SYMBOL(ftape_tracing);
+EXPORT_SYMBOL(ftape_function_nest_level);
+EXPORT_SYMBOL(ftape_trace_call);
+EXPORT_SYMBOL(ftape_trace_exit);
+EXPORT_SYMBOL(ftape_trace_log);
+#endif
+
diff --git a/drivers/char/ftape/zftape/Makefile b/drivers/char/ftape/zftape/Makefile
new file mode 100644
index 0000000..6d91c1f
--- /dev/null
+++ b/drivers/char/ftape/zftape/Makefile
@@ -0,0 +1,36 @@
+#
+#       Copyright (C) 1996, 1997 Claus-Justus Heine.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2, or (at your option)
+# any later version.
+# 
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with this program; see the file COPYING.  If not, write to
+# the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+#
+# $Source: /homes/cvs/ftape-stacked/ftape/zftape/Makefile,v $
+# $Revision: 1.4 $
+# $Date: 1997/10/05 19:18:58 $
+#
+#      Makefile for the QIC-40/80/3010/3020 zftape interface VFS to
+#      ftape
+#
+
+
+# ZFT_OBSOLETE - enable the MTIOC_ZFTAPE_GETBLKSZ ioctl. You should
+#                leave this enabled for compatibility with taper.
+
+obj-$(CONFIG_ZFTAPE) += zftape.o
+
+zftape-objs := zftape-rw.o zftape-ctl.o zftape-read.o \
+	       zftape-write.o zftape-vtbl.o zftape-eof.o \
+	       zftape-init.o zftape-buffers.o zftape_syms.o
+
+EXTRA_CFLAGS := -DZFT_OBSOLETE
diff --git a/drivers/char/ftape/zftape/zftape-buffers.c b/drivers/char/ftape/zftape/zftape-buffers.c
new file mode 100644
index 0000000..da06f13
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-buffers.c
@@ -0,0 +1,149 @@
+/*
+ *      Copyright (C) 1995-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-buffers.c,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:59 $
+ *
+ *      This file contains the dynamic buffer allocation routines 
+ *      of zftape
+ */
+
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+
+#include <linux/zftape.h>
+
+#include <linux/vmalloc.h>
+
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-eof.h"
+#include "../zftape/zftape-ctl.h"
+#include "../zftape/zftape-write.h"
+#include "../zftape/zftape-read.h"
+#include "../zftape/zftape-rw.h"
+#include "../zftape/zftape-vtbl.h"
+
+/*  global variables
+ */
+
+/*  local varibales
+ */
+static unsigned int used_memory;
+static unsigned int peak_memory;
+
+void zft_memory_stats(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_noise, "Memory usage (vmalloc allocations):\n"
+	      KERN_INFO "total allocated: %d\n"
+	      KERN_INFO "peak allocation: %d",
+	      used_memory, peak_memory);
+	peak_memory = used_memory;
+	TRACE_EXIT;
+}
+
+int zft_vcalloc_once(void *new, size_t size)
+{
+	TRACE_FUN(ft_t_flow);
+	if (zft_vmalloc_once(new, size) < 0) {
+		TRACE_EXIT -ENOMEM;
+	}
+	memset(*(void **)new, '\0', size);
+	TRACE_EXIT 0;
+}
+int zft_vmalloc_once(void *new, size_t size)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (*(void **)new != NULL || size == 0) {
+		TRACE_EXIT 0;
+	}
+	if ((*(void **)new = vmalloc(size)) == NULL) {
+		TRACE_EXIT -ENOMEM;
+	}
+	used_memory += size;
+	if (peak_memory < used_memory) {
+		peak_memory = used_memory;
+	}
+	TRACE_ABORT(0, ft_t_noise,
+		    "allocated buffer @ %p, %d bytes", *(void **)new, size);
+}
+int zft_vmalloc_always(void *new, size_t size)
+{
+	TRACE_FUN(ft_t_flow);
+
+	zft_vfree(new, size);
+	TRACE_EXIT zft_vmalloc_once(new, size);
+}
+void zft_vfree(void *old, size_t size)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (*(void **)old) {
+		vfree(*(void **)old);
+		used_memory -= size;
+		TRACE(ft_t_noise, "released buffer @ %p, %d bytes",
+		      *(void **)old, size);
+		*(void **)old = NULL;
+	}
+	TRACE_EXIT;
+}
+
+void *zft_kmalloc(size_t size)
+{
+	void *new;
+
+	while ((new = kmalloc(size, GFP_KERNEL)) == NULL) {
+		msleep_interruptible(100);
+	}
+	memset(new, 0, size);
+	used_memory += size;
+	if (peak_memory < used_memory) {
+		peak_memory = used_memory;
+	}
+	return new;
+}
+
+void zft_kfree(void *old, size_t size)
+{
+	kfree(old);
+	used_memory -= size;
+}
+
+/* there are some more buffers that are allocated on demand.
+ * cleanup_module() calles this function to be sure to have released
+ * them 
+ */
+void zft_uninit_mem(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	zft_vfree(&zft_hseg_buf, FT_SEGMENT_SIZE);
+	zft_vfree(&zft_deblock_buf, FT_SEGMENT_SIZE); zft_deblock_segment = -1;
+	zft_free_vtbl();
+	if (zft_cmpr_lock(0 /* don't load */) == 0) {
+		(*zft_cmpr_ops->cleanup)();
+		(*zft_cmpr_ops->reset)(); /* unlock it again */
+	}
+	zft_memory_stats();
+	TRACE_EXIT;
+}
diff --git a/drivers/char/ftape/zftape/zftape-buffers.h b/drivers/char/ftape/zftape/zftape-buffers.h
new file mode 100644
index 0000000..798e312
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-buffers.h
@@ -0,0 +1,55 @@
+#ifndef _FTAPE_DYNMEM_H
+#define _FTAPE_DYNMEM_H
+
+/*
+ *      Copyright (C) 1995-1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-buffers.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:18:59 $
+ *
+ *   memory allocation routines.
+ *
+ */
+
+/* we do not allocate all of the really large buffer memory before
+ * someone tries to open the drive. ftape_open() may fail with
+ * -ENOMEM, but that's better having 200k of vmalloced memory which
+ * cannot be swapped out.
+ */
+
+extern void  zft_memory_stats(void);
+extern int   zft_vmalloc_once(void *new, size_t size);
+extern int   zft_vcalloc_once(void *new, size_t size);
+extern int   zft_vmalloc_always(void *new, size_t size);
+extern void  zft_vfree(void *old, size_t size);
+extern void *zft_kmalloc(size_t size);
+extern void  zft_kfree(void *old, size_t size);
+
+/* called by cleanup_module() 
+ */
+extern void zft_uninit_mem(void);
+
+#endif
+
+
+
+
+
+
+
diff --git a/drivers/char/ftape/zftape/zftape-ctl.c b/drivers/char/ftape/zftape/zftape-ctl.c
new file mode 100644
index 0000000..6c7874e5
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-ctl.c
@@ -0,0 +1,1418 @@
+/* 
+ *      Copyright (C) 1996, 1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-ctl.c,v $
+ * $Revision: 1.2.6.2 $
+ * $Date: 1997/11/14 18:07:33 $
+ *
+ *      This file contains the non-read/write zftape functions
+ *      for the QIC-40/80/3010/3020 floppy-tape driver for Linux.
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/fcntl.h>
+
+#include <linux/zftape.h>
+
+#include <asm/uaccess.h>
+
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-eof.h"
+#include "../zftape/zftape-ctl.h"
+#include "../zftape/zftape-write.h"
+#include "../zftape/zftape-read.h"
+#include "../zftape/zftape-rw.h"
+#include "../zftape/zftape-vtbl.h"
+
+/*      Global vars.
+ */
+int zft_write_protected; /* this is when cartridge rdonly or O_RDONLY */
+int zft_header_read;
+int zft_offline;
+unsigned int zft_unit;
+int zft_resid;
+int zft_mt_compression;
+
+/*      Local vars.
+ */
+static int going_offline;
+
+typedef int (mt_fun)(int *argptr);
+typedef int (*mt_funp)(int *argptr);
+typedef struct
+{
+	mt_funp function;
+	unsigned offline         : 1; /* op permitted if offline or no_tape */
+	unsigned write_protected : 1; /* op permitted if write-protected    */
+	unsigned not_formatted   : 1; /* op permitted if tape not formatted */
+	unsigned raw_mode        : 1; /* op permitted if zft_mode == 0    */
+	unsigned need_idle_state : 1; /* need to call def_idle_state        */
+	char     *name;
+} fun_entry;
+
+static mt_fun mt_dummy, mt_reset, mt_fsr, mt_bsr, mt_rew, mt_offl, mt_nop,
+	mt_weof, mt_erase, mt_ras2, mt_setblk, mt_setdensity,
+	mt_seek, mt_tell, mt_reten, mt_eom, mt_fsf, mt_bsf,
+	mt_fsfm, mt_bsfm, mt_setdrvbuffer, mt_compression;
+
+static fun_entry mt_funs[]=
+{ 
+	{mt_reset       , 1, 1, 1, 1, 0, "MT_RESET" }, /*  0 */
+	{mt_fsf         , 0, 1, 0, 0, 1, "MT_FSF"   },
+	{mt_bsf         , 0, 1, 0, 0, 1, "MT_BSF"   },
+	{mt_fsr         , 0, 1, 0, 1, 1, "MT_FSR"   },
+	{mt_bsr         , 0, 1, 0, 1, 1, "MT_BSR"   },
+	{mt_weof        , 0, 0, 0, 0, 0, "MT_WEOF"  }, /*  5 */
+	{mt_rew         , 0, 1, 1, 1, 0, "MT_REW"   },
+	{mt_offl        , 0, 1, 1, 1, 0, "MT_OFFL"  },
+	{mt_nop         , 1, 1, 1, 1, 0, "MT_NOP"   },
+	{mt_reten       , 0, 1, 1, 1, 0, "MT_RETEN" },
+	{mt_bsfm        , 0, 1, 0, 0, 1, "MT_BSFM"  }, /* 10 */
+	{mt_fsfm        , 0, 1, 0, 0, 1, "MT_FSFM"  },
+	{mt_eom         , 0, 1, 0, 0, 1, "MT_EOM"   },
+	{mt_erase       , 0, 0, 0, 1, 0, "MT_ERASE" },
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_RAS1"  },
+	{mt_ras2        , 0, 0, 0, 1, 0, "MT_RAS2"  },
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_RAS3"  },
+	{mt_dummy       , 1, 1, 1, 1, 0, "UNKNOWN"  },
+	{mt_dummy       , 1, 1, 1, 1, 0, "UNKNOWN"  },
+	{mt_dummy       , 1, 1, 1, 1, 0, "UNKNOWN"  },
+	{mt_setblk      , 1, 1, 1, 1, 1, "MT_SETBLK"}, /* 20 */
+	{mt_setdensity  , 1, 1, 1, 1, 0, "MT_SETDENSITY"},
+	{mt_seek        , 0, 1, 0, 1, 1, "MT_SEEK"  },
+	{mt_dummy       , 0, 1, 0, 1, 1, "MT_TELL"  }, /* wr-only ?! */
+	{mt_setdrvbuffer, 1, 1, 1, 1, 0, "MT_SETDRVBUFFER" },
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_FSS"   }, /* 25 */
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_BSS"   },
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_WSM"   },
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_LOCK"  },
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_UNLOCK"},
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_LOAD"  }, /* 30 */
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_UNLOAD"},
+	{mt_compression , 1, 1, 1, 0, 1, "MT_COMPRESSION"},
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_SETPART"},
+	{mt_dummy       , 1, 1, 1, 1, 0, "MT_MKPART"}
+};  
+
+#define NR_MT_CMDS NR_ITEMS(mt_funs)
+
+void zft_reset_position(zft_position *pos)
+{
+	TRACE_FUN(ft_t_flow);
+
+	pos->seg_byte_pos =
+		pos->volume_pos = 0;
+	if (zft_header_read) {
+		/* need to keep track of the volume table and
+		 * compression map. We therefor simply
+		 * position at the beginning of the first
+		 * volume. This covers old ftape archives as
+		 * well has various flavours of the
+		 * compression map segments. The worst case is
+		 * that the compression map shows up as a
+		 * additional volume in front of all others.
+		 */
+		pos->seg_pos  = zft_find_volume(0)->start_seg;
+		pos->tape_pos = zft_calc_tape_pos(pos->seg_pos);
+	} else {
+		pos->tape_pos =  0;
+		pos->seg_pos  = -1;
+	}
+	zft_just_before_eof =  0;
+	zft_deblock_segment = -1;
+	zft_io_state        = zft_idle;
+	zft_zap_read_buffers();
+	zft_prevent_flush();
+	/*  unlock the compresison module if it is loaded.
+	 *  The zero arg means not to try to load the module.
+	 */
+	if (zft_cmpr_lock(0) == 0) {
+		(*zft_cmpr_ops->reset)(); /* unlock */
+	}
+	TRACE_EXIT;
+}
+
+static void zft_init_driver(void)
+{
+	TRACE_FUN(ft_t_flow);
+
+	zft_resid =
+		zft_header_read          =
+		zft_old_ftape            =
+		zft_offline              =
+		zft_write_protected      =
+		going_offline            =
+		zft_mt_compression       =
+		zft_header_changed       =
+		zft_volume_table_changed =
+		zft_written_segments     = 0;
+	zft_blk_sz = CONFIG_ZFT_DFLT_BLK_SZ;
+	zft_reset_position(&zft_pos); /* does most of the stuff */
+	ftape_zap_read_buffers();
+	ftape_set_state(idle);
+	TRACE_EXIT;
+}
+
+int zft_def_idle_state(void)
+{ 
+	int result = 0;
+	TRACE_FUN(ft_t_flow);
+	
+	if (!zft_header_read) {
+		result = zft_read_header_segments();
+	} else if ((result = zft_flush_buffers()) >= 0 && zft_qic_mode) {
+		/*  don't move past eof
+		 */
+		(void)zft_close_volume(&zft_pos);
+	}
+	if (ftape_abort_operation() < 0) {
+		TRACE(ft_t_warn, "ftape_abort_operation() failed");
+		result = -EIO;
+	}
+	/* clear remaining read buffers */
+	zft_zap_read_buffers();
+	zft_io_state = zft_idle;
+	TRACE_EXIT result;
+}
+
+/*****************************************************************************
+ *                                                                           *
+ *  functions for the MTIOCTOP commands                                      *
+ *                                                                           *
+ *****************************************************************************/
+
+static int mt_dummy(int *dummy)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE_EXIT -ENOSYS;
+}
+
+static int mt_reset(int *dummy)
+{        
+	TRACE_FUN(ft_t_flow);
+	
+	(void)ftape_seek_to_bot();
+	TRACE_CATCH(ftape_reset_drive(),
+		    zft_init_driver(); zft_uninit_mem(); zft_offline = 1);
+	/*  fake a re-open of the device. This will set all flage and 
+	 *  allocate buffers as appropriate. The new tape condition will
+	 *  force the open routine to do anything we need.
+	 */
+	TRACE_CATCH(_zft_open(-1 /* fake reopen */, 0 /* dummy */),);
+	TRACE_EXIT 0;
+}
+
+static int mt_fsf(int *arg)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	result = zft_skip_volumes(*arg, &zft_pos);
+	zft_just_before_eof = 0;
+	TRACE_EXIT result;
+}
+
+static int mt_bsf(int *arg)
+{
+	int result = 0;
+	TRACE_FUN(ft_t_flow);
+	
+	if (*arg != 0) {
+		result = zft_skip_volumes(-*arg + 1, &zft_pos);
+	}
+	TRACE_EXIT result;
+}
+
+static int seek_block(__s64 data_offset,
+		      __s64 block_increment,
+		      zft_position *pos)
+{ 
+	int result      = 0;
+	__s64 new_block_pos;
+	__s64 vol_block_count;
+	const zft_volinfo *volume;
+	int exceed;
+	TRACE_FUN(ft_t_flow);
+	
+	volume = zft_find_volume(pos->seg_pos);
+	if (volume->start_seg == 0 || volume->end_seg == 0) {
+		TRACE_EXIT -EIO;
+	}
+	new_block_pos   = (zft_div_blksz(data_offset, volume->blk_sz)
+			   + block_increment);
+	vol_block_count = zft_div_blksz(volume->size, volume->blk_sz);
+	if (new_block_pos < 0) {
+		TRACE(ft_t_noise,
+		      "new_block_pos " LL_X " < 0", LL(new_block_pos));
+		zft_resid     = (int)new_block_pos;
+		new_block_pos = 0;
+		exceed = 1;
+	} else if (new_block_pos > vol_block_count) {
+		TRACE(ft_t_noise,
+		      "new_block_pos " LL_X " exceeds size of volume " LL_X,
+		      LL(new_block_pos), LL(vol_block_count));
+		zft_resid     = (int)(vol_block_count - new_block_pos);
+		new_block_pos = vol_block_count;
+		exceed = 1;
+	} else {
+		exceed = 0;
+	}
+	if (zft_use_compression && volume->use_compression) {
+		TRACE_CATCH(zft_cmpr_lock(1 /* try to load */),);
+		result = (*zft_cmpr_ops->seek)(new_block_pos, pos, volume,
+					       zft_deblock_buf);
+		pos->tape_pos  = zft_calc_tape_pos(pos->seg_pos);
+		pos->tape_pos += pos->seg_byte_pos;
+	} else {
+		pos->volume_pos = zft_mul_blksz(new_block_pos, volume->blk_sz);
+		pos->tape_pos   = zft_calc_tape_pos(volume->start_seg);
+		pos->tape_pos  += pos->volume_pos;
+		pos->seg_pos    = zft_calc_seg_byte_coord(&pos->seg_byte_pos,
+							  pos->tape_pos);
+	}
+	zft_just_before_eof = volume->size == pos->volume_pos;
+	if (zft_just_before_eof) {
+		/* why this? because zft_file_no checks agains start
+		 * and end segment of a volume. We do not want to
+		 * advance to the next volume with this function.
+		 */
+		TRACE(ft_t_noise, "set zft_just_before_eof");
+		zft_position_before_eof(pos, volume);
+	}
+	TRACE(ft_t_noise, "\n"
+	      KERN_INFO "new_seg_pos : %d\n"
+	      KERN_INFO "new_tape_pos: " LL_X "\n"
+	      KERN_INFO "vol_size    : " LL_X "\n"
+	      KERN_INFO "seg_byte_pos: %d\n"
+	      KERN_INFO "blk_sz  : %d", 
+	      pos->seg_pos, LL(pos->tape_pos),
+	      LL(volume->size), pos->seg_byte_pos,
+	      volume->blk_sz);
+	if (!exceed) {
+		zft_resid = new_block_pos - zft_div_blksz(pos->volume_pos,
+							  volume->blk_sz);
+	}
+	if (zft_resid < 0) {
+		zft_resid = -zft_resid;
+	}
+	TRACE_EXIT ((exceed || zft_resid != 0) && result >= 0) ? -EINVAL : result;
+}     
+
+static int mt_fsr(int *arg)
+{ 
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	result = seek_block(zft_pos.volume_pos,  *arg, &zft_pos);
+	TRACE_EXIT result;
+}
+
+static int mt_bsr(int *arg)
+{   
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	result = seek_block(zft_pos.volume_pos, -*arg, &zft_pos);
+	TRACE_EXIT result;
+}
+
+static int mt_weof(int *arg)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE_CATCH(zft_flush_buffers(),);
+	result = zft_weof(*arg, &zft_pos);
+	TRACE_EXIT result;
+}
+
+static int mt_rew(int *dummy)
+{          
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	if(zft_header_read) {
+		(void)zft_def_idle_state();
+	}
+	result = ftape_seek_to_bot();
+	zft_reset_position(&zft_pos);
+	TRACE_EXIT result;
+}
+
+static int mt_offl(int *dummy)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	going_offline= 1;
+	result = mt_rew(NULL);
+	TRACE_EXIT result;
+}
+
+static int mt_nop(int *dummy)
+{
+	TRACE_FUN(ft_t_flow);
+	/*  should we set tape status?
+	 */
+	if (!zft_offline) { /* offline includes no_tape */
+		(void)zft_def_idle_state();
+	}
+	TRACE_EXIT 0; 
+}
+
+static int mt_reten(int *dummy)
+{  
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	if(zft_header_read) {
+		(void)zft_def_idle_state();
+	}
+	result = ftape_seek_to_eot();
+	if (result >= 0) {
+		result = ftape_seek_to_bot();
+	}
+	TRACE_EXIT(result);
+}
+
+static int fsfbsfm(int arg, zft_position *pos)
+{ 
+	const zft_volinfo *vtbl;
+	__s64 block_pos;
+	TRACE_FUN(ft_t_flow);
+	
+	/* What to do? This should seek to the next file-mark and
+	 * position BEFORE. That is, a next write would just extend
+	 * the current file.  Well. Let's just seek to the end of the
+	 * current file, if count == 1.  If count > 1, then do a
+	 * "mt_fsf(count - 1)", and then seek to the end of that file.
+	 * If count == 0, do nothing
+	 */
+	if (arg == 0) {
+		TRACE_EXIT 0;
+	}
+	zft_just_before_eof = 0;
+	TRACE_CATCH(zft_skip_volumes(arg < 0 ? arg : arg-1, pos),
+		    if (arg > 0) {
+			    zft_resid ++; 
+		    });
+	vtbl      = zft_find_volume(pos->seg_pos);
+	block_pos = zft_div_blksz(vtbl->size, vtbl->blk_sz);
+	(void)seek_block(0, block_pos, pos);
+	if (pos->volume_pos != vtbl->size) {
+		zft_just_before_eof = 0;
+		zft_resid = 1;
+		/* we didn't managed to go there */
+		TRACE_ABORT(-EIO, ft_t_err, 
+			    "wanted file position " LL_X ", arrived at " LL_X, 
+			    LL(vtbl->size), LL(pos->volume_pos));
+	}
+	zft_just_before_eof = 1;
+	TRACE_EXIT 0; 
+}
+
+static int mt_bsfm(int *arg)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	result = fsfbsfm(-*arg, &zft_pos);
+	TRACE_EXIT result;
+}
+
+static int mt_fsfm(int *arg)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	result = fsfbsfm(*arg, &zft_pos);
+	TRACE_EXIT result;
+}
+
+static int mt_eom(int *dummy)
+{              
+	TRACE_FUN(ft_t_flow);
+	
+	zft_skip_to_eom(&zft_pos);
+	TRACE_EXIT 0;
+}
+
+static int mt_erase(int *dummy)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	result = zft_erase();
+	TRACE_EXIT result;
+}
+
+static int mt_ras2(int *dummy)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	result = -ENOSYS;
+	TRACE_EXIT result;
+} 
+
+/*  Sets the new blocksize in BYTES
+ *
+ */
+static int mt_setblk(int *new_size)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	if((unsigned int)(*new_size) > ZFT_MAX_BLK_SZ) {
+		TRACE_ABORT(-EINVAL, ft_t_info,
+			    "desired blk_sz (%d) should be <= %d bytes",
+			    *new_size, ZFT_MAX_BLK_SZ);
+	}
+	if ((*new_size & (FT_SECTOR_SIZE-1)) != 0) {
+		TRACE_ABORT(-EINVAL, ft_t_info,
+			"desired blk_sz (%d) must be a multiple of %d bytes",
+			    *new_size, FT_SECTOR_SIZE);
+	}
+	if (*new_size == 0) {
+		if (zft_use_compression) {
+			TRACE_ABORT(-EINVAL, ft_t_info,
+				    "Variable block size not yet "
+				    "supported with compression");
+		}
+		*new_size = 1;
+	}
+	zft_blk_sz = *new_size;
+	TRACE_EXIT 0;
+} 
+
+static int mt_setdensity(int *arg)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	SET_TRACE_LEVEL(*arg);
+	TRACE(TRACE_LEVEL, "tracing set to %d", TRACE_LEVEL);
+	if ((int)TRACE_LEVEL != *arg) {
+		TRACE_EXIT -EINVAL;
+	}
+	TRACE_EXIT 0;
+}          
+
+static int mt_seek(int *new_block_pos)
+{ 
+	int result= 0;        
+	TRACE_FUN(ft_t_any);
+	
+	result = seek_block(0, (__s64)*new_block_pos, &zft_pos);
+	TRACE_EXIT result;
+}
+
+/*  OK, this is totally different from SCSI, but the worst thing that can 
+ *  happen is that there is not enough defragmentated memory that can be 
+ *  allocated. Also, there is a hardwired limit of 16 dma buffers in the 
+ *  stock ftape module. This shouldn't bring the system down.
+ *
+ * NOTE: the argument specifies the total number of dma buffers to use.
+ *       The driver needs at least 3 buffers to function at all.
+ * 
+ */
+static int mt_setdrvbuffer(int *cnt)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (*cnt < 3) {
+		TRACE_EXIT -EINVAL;
+	}
+	TRACE_CATCH(ftape_set_nr_buffers(*cnt),);
+	TRACE_EXIT 0;
+}
+/* return the block position from start of volume 
+ */
+static int mt_tell(int *arg)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	*arg   = zft_div_blksz(zft_pos.volume_pos,
+			       zft_find_volume(zft_pos.seg_pos)->blk_sz);
+	TRACE_EXIT 0;
+}
+
+static int mt_compression(int *arg)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	/*  Ok. We could also check whether compression is available at
+	 *  all by trying to load the compression module.  We could
+	 *  also check for a block size of 1 byte which is illegal
+	 *  with compression.  Instead of doing it here we rely on
+	 *  zftape_write() to do the proper checks.
+	 */
+	if ((unsigned int)*arg > 1) {
+		TRACE_EXIT -EINVAL;
+	}
+	if (*arg != 0 && zft_blk_sz == 1) { /* variable block size */
+		TRACE_ABORT(-EINVAL, ft_t_info,
+			    "Compression not yet supported "
+			    "with variable block size");
+	}
+	zft_mt_compression  = *arg;
+	if ((zft_unit & ZFT_ZIP_MODE) == 0) {
+		zft_use_compression = zft_mt_compression;
+	}
+	TRACE_EXIT 0;
+}
+
+/*  check whether write access is allowed. Write access is denied when
+ *  + zft_write_protected == 1 -- this accounts for either hard write 
+ *                                protection of the cartridge or for 
+ *                                O_RDONLY access mode of the tape device
+ *  + zft_offline == 1         -- this meany that there is either no tape 
+ *                                or that the MTOFFLINE ioctl has been 
+ *                                previously issued (`soft eject')
+ *  + ft_formatted == 0        -- this means that the cartridge is not
+ *                                formatted
+ *  Then we distinuguish two cases. When zft_qic_mode is TRUE, then we try
+ *  to emulate a `traditional' (aka SCSI like) UN*X tape device. Therefore we
+ *  deny writes when
+ *  + zft_qic_mode ==1 && 
+ *       (!zft_tape_at_lbot() &&   -- tape no at logical BOT
+ *        !(zft_tape_at_eom() ||   -- tape not at logical EOM (or EOD)
+ *          (zft_tape_at_eom() &&
+ *           zft_old_ftape())))    -- we can't add new volume to tapes 
+ *                                    written by old ftape because ftape
+ *                                    don't use the volume table
+ *
+ *  when the drive is in true raw mode (aka /dev/rawft0) then we don't 
+ *  care about LBOT and EOM conditions. This device is intended for a 
+ *  user level program that wants to truly implement the QIC-80 compliance
+ *  at the logical data layout level of the cartridge, i.e. implement all
+ *  that volume table and volume directory stuff etc.<
+ */
+int zft_check_write_access(zft_position *pos)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (zft_offline) { /* offline includes no_tape */
+		TRACE_ABORT(-ENXIO,
+			    ft_t_info, "tape is offline or no cartridge");
+	}
+	if (!ft_formatted) {
+		TRACE_ABORT(-EACCES, ft_t_info, "tape is not formatted");
+	} 
+	if (zft_write_protected) {
+		TRACE_ABORT(-EACCES, ft_t_info, "cartridge write protected");
+	} 
+	if (zft_qic_mode) {
+		/*  check BOT condition */
+		if (!zft_tape_at_lbot(pos)) {
+			/*  protect cartridges written by old ftape if
+			 *  not at BOT because they use the vtbl
+			 *  segment for storing data
+			 */
+			if (zft_old_ftape) {
+				TRACE_ABORT(-EACCES, ft_t_warn, 
+      "Cannot write to cartridges written by old ftape when not at BOT");
+			}
+			/*  not at BOT, but allow writes at EOD, of course
+			 */
+			if (!zft_tape_at_eod(pos)) {
+				TRACE_ABORT(-EACCES, ft_t_info,
+					    "tape not at BOT and not at EOD");
+			}
+		}
+		/*  fine. Now the tape is either at BOT or at EOD. */
+	}
+	/* or in raw mode in which case we don't care about BOT and EOD */
+	TRACE_EXIT 0;
+}
+
+/*      OPEN routine called by kernel-interface code
+ *
+ *      NOTE: this is also called by mt_reset() with dev_minor == -1
+ *            to fake a reopen after a reset.
+ */
+int _zft_open(unsigned int dev_minor, unsigned int access_mode)
+{
+	static unsigned int tape_unit;
+	static unsigned int file_access_mode;
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	if ((int)dev_minor == -1) {
+		/* fake reopen */
+		zft_unit    = tape_unit;
+		access_mode = file_access_mode;
+		zft_init_driver(); /* reset all static data to defaults */
+	} else {
+		tape_unit        = dev_minor;
+		file_access_mode = access_mode;
+		if ((result = ftape_enable(FTAPE_SEL(dev_minor))) < 0) {
+			TRACE_ABORT(-ENXIO, ft_t_err,
+				    "ftape_enable failed: %d", result);
+		}
+		if (ft_new_tape || ft_no_tape || !ft_formatted ||
+		    (FTAPE_SEL(zft_unit) != FTAPE_SEL(dev_minor)) ||
+		    (zft_unit & ZFT_RAW_MODE) != (dev_minor & ZFT_RAW_MODE)) {
+			/* reset all static data to defaults,
+			 */
+			zft_init_driver(); 
+		}
+		zft_unit = dev_minor;
+	}
+	zft_set_flags(zft_unit); /* decode the minor bits */
+	if (zft_blk_sz == 1 && zft_use_compression) {
+		ftape_disable(); /* resets ft_no_tape */
+		TRACE_ABORT(-ENODEV, ft_t_warn, "Variable block size not yet "
+			    "supported with compression");
+	}
+	/*  no need for most of the buffers when no tape or not
+	 *  formatted.  for the read/write operations, it is the
+	 *  regardless whether there is no tape, a not-formatted tape
+	 *  or the whether the driver is soft offline.  
+	 *  Nevertheless we allow some ioctls with non-formatted tapes, 
+	 *  like rewind and reset.
+	 */
+	if (ft_no_tape || !ft_formatted) {
+		zft_uninit_mem();
+	}
+	if (ft_no_tape) {
+		zft_offline = 1; /* so we need not test two variables */
+	}
+	if ((access_mode == O_WRONLY || access_mode == O_RDWR) &&
+	    (ft_write_protected || ft_no_tape)) {
+		ftape_disable(); /* resets ft_no_tape */
+		TRACE_ABORT(ft_no_tape ? -ENXIO : -EROFS,
+			    ft_t_warn, "wrong access mode %s cartridge",
+			    ft_no_tape ? "without a" : "with write protected");
+	}
+	zft_write_protected = (access_mode == O_RDONLY || 
+			       ft_write_protected != 0);
+	if (zft_write_protected) {
+		TRACE(ft_t_noise,
+		      "read only access mode: %d, "
+		      "drive write protected: %d", 
+		      access_mode == O_RDONLY,
+		      ft_write_protected != 0);
+	}
+	if (!zft_offline) {
+		TRACE_CATCH(zft_vmalloc_once(&zft_deblock_buf,FT_SEGMENT_SIZE),
+			    ftape_disable());
+	}
+	/* zft_seg_pos should be greater than the vtbl segpos but not
+	 * if in compatibility mode and only after we read in the
+	 * header segments
+	 *
+	 * might also be a problem if the user makes a backup with a
+	 * *qft* device and rewinds it with a raw device.
+	 */
+	if (zft_qic_mode         &&
+	    !zft_old_ftape       &&
+	    zft_pos.seg_pos >= 0 &&
+	    zft_header_read      && 
+	    zft_pos.seg_pos <= ft_first_data_segment) {
+		TRACE(ft_t_noise, "you probably mixed up the zftape devices!");
+		zft_reset_position(&zft_pos); 
+	}
+	TRACE_EXIT 0;
+}
+
+/*      RELEASE routine called by kernel-interface code
+ */
+int _zft_close(void)
+{
+	int result = 0;
+	TRACE_FUN(ft_t_flow);
+	
+	if (zft_offline) {
+		/* call the hardware release routine. Puts the drive offline */
+		ftape_disable();
+		TRACE_EXIT 0;
+	}
+	if (!(ft_write_protected || zft_old_ftape)) {
+		result = zft_flush_buffers();
+		TRACE(ft_t_noise, "writing file mark at current position");
+		if (zft_qic_mode && zft_close_volume(&zft_pos) == 0) {
+			zft_move_past_eof(&zft_pos);
+		}
+		if ((zft_tape_at_lbot(&zft_pos) ||
+		     !(zft_unit & FTAPE_NO_REWIND))) {
+			if (result >= 0) {
+				result = zft_update_header_segments();
+			} else {
+				TRACE(ft_t_err,
+				"Error: unable to update header segments");
+			}
+		}
+	}
+	ftape_abort_operation();
+	if (!(zft_unit & FTAPE_NO_REWIND)) {
+		TRACE(ft_t_noise, "rewinding tape");
+		if (ftape_seek_to_bot() < 0 && result >= 0) {
+			result = -EIO; /* keep old value */
+		}
+		zft_reset_position(&zft_pos);
+	} 
+	zft_zap_read_buffers();
+	/*  now free up memory as much as possible. We don't destroy
+	 *  the deblock buffer if it containes a valid segment.
+	 */
+	if (zft_deblock_segment == -1) {
+		zft_vfree(&zft_deblock_buf, FT_SEGMENT_SIZE); 
+	}
+	/* high level driver status, forces creation of a new volume
+	 * when calling ftape_write again and not zft_just_before_eof
+	 */
+	zft_io_state = zft_idle;  
+	if (going_offline) {
+		zft_init_driver();
+		zft_uninit_mem();
+		going_offline = 0;
+		zft_offline   = 1;
+	} else if (zft_cmpr_lock(0 /* don't load */) == 0) {
+		(*zft_cmpr_ops->reset)(); /* unlock it again */
+	}
+	zft_memory_stats();
+	/* call the hardware release routine. Puts the drive offline */
+	ftape_disable();
+	TRACE_EXIT result;
+}
+
+/*
+ *  the wrapper function around the wrapper MTIOCTOP ioctl
+ */
+static int mtioctop(struct mtop *mtop, int arg_size)
+{
+	int result = 0;
+	fun_entry *mt_fun_entry;
+	TRACE_FUN(ft_t_flow);
+	
+	if (arg_size != sizeof(struct mtop) || mtop->mt_op >= NR_MT_CMDS) {
+		TRACE_EXIT -EINVAL;
+	}
+	TRACE(ft_t_noise, "calling MTIOCTOP command: %s",
+	      mt_funs[mtop->mt_op].name);
+	mt_fun_entry= &mt_funs[mtop->mt_op];
+	zft_resid = mtop->mt_count;
+	if (!mt_fun_entry->offline && zft_offline) {
+		if (ft_no_tape) {
+			TRACE_ABORT(-ENXIO, ft_t_info, "no tape present");
+		} else {
+			TRACE_ABORT(-ENXIO, ft_t_info, "drive is offline");
+		}
+	}
+	if (!mt_fun_entry->not_formatted && !ft_formatted) {
+		TRACE_ABORT(-EACCES, ft_t_info, "tape is not formatted");
+	}
+	if (!mt_fun_entry->write_protected) {
+		TRACE_CATCH(zft_check_write_access(&zft_pos),);
+	}
+	if (mt_fun_entry->need_idle_state && !(zft_offline || !ft_formatted)) {
+		TRACE_CATCH(zft_def_idle_state(),);
+	}
+	if (!zft_qic_mode && !mt_fun_entry->raw_mode) {
+		TRACE_ABORT(-EACCES, ft_t_info, 
+"Drive needs to be in QIC-80 compatibility mode for this command");
+	}
+	result = (mt_fun_entry->function)(&mtop->mt_count);
+	if (zft_tape_at_lbot(&zft_pos)) {
+		TRACE_CATCH(zft_update_header_segments(),);
+	}
+	if (result >= 0) {
+		zft_resid = 0;
+	}
+	TRACE_EXIT result;
+}
+
+/*
+ *  standard MTIOCGET ioctl
+ */
+static int mtiocget(struct mtget *mtget, int arg_size)
+{
+	const zft_volinfo *volume;
+	__s64 max_tape_pos;
+	TRACE_FUN(ft_t_flow);
+	
+	if (arg_size != sizeof(struct mtget)) {
+		TRACE_ABORT(-EINVAL, ft_t_info, "bad argument size: %d",
+			    arg_size);
+	}
+	mtget->mt_type  = ft_drive_type.vendor_id + 0x800000;
+	mtget->mt_dsreg = ft_last_status.space;
+	mtget->mt_erreg = ft_last_error.space; /* error register */
+	mtget->mt_resid = zft_resid; /* residuum of writes, reads and
+				      * MTIOCTOP commands 
+				      */
+	if (!zft_offline) { /* neither no_tape nor soft offline */
+		mtget->mt_gstat = GMT_ONLINE(~0UL);
+		/* should rather return the status of the cartridge
+		 * than the access mode of the file, therefor use
+		 * ft_write_protected, not zft_write_protected 
+		 */
+		if (ft_write_protected) {
+			mtget->mt_gstat |= GMT_WR_PROT(~0UL);
+		}
+		if(zft_header_read) { /* this catches non-formatted */
+			volume = zft_find_volume(zft_pos.seg_pos);
+			mtget->mt_fileno = volume->count;
+			max_tape_pos = zft_capacity - zft_blk_sz;
+			if (zft_use_compression) {
+				max_tape_pos -= ZFT_CMPR_OVERHEAD;
+			}
+			if (zft_tape_at_eod(&zft_pos)) {
+				mtget->mt_gstat |= GMT_EOD(~0UL);
+			}
+			if (zft_pos.tape_pos > max_tape_pos) {
+				mtget->mt_gstat |= GMT_EOT(~0UL);
+			}
+			mtget->mt_blkno = zft_div_blksz(zft_pos.volume_pos,
+							volume->blk_sz);
+			if (zft_just_before_eof) {
+				mtget->mt_gstat |= GMT_EOF(~0UL);
+			}
+			if (zft_tape_at_lbot(&zft_pos)) {
+				mtget->mt_gstat |= GMT_BOT(~0UL);
+			}
+		} else {
+			mtget->mt_fileno = mtget->mt_blkno = -1;
+			if (mtget->mt_dsreg & QIC_STATUS_AT_BOT) {
+				mtget->mt_gstat |= GMT_BOT(~0UL);
+			}
+		}
+	} else {
+		if (ft_no_tape) {
+			mtget->mt_gstat = GMT_DR_OPEN(~0UL);
+		} else {
+			mtget->mt_gstat = 0UL;
+		}
+ 		mtget->mt_fileno = mtget->mt_blkno = -1;
+	}
+	TRACE_EXIT 0;
+}
+
+#ifdef MTIOCRDFTSEG
+/*
+ *  Read a floppy tape segment. This is useful for manipulating the
+ *  volume table, and read the old header segment before re-formatting
+ *  the cartridge.
+ */
+static int mtiocrdftseg(struct mtftseg * mtftseg, int arg_size)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE(ft_t_noise, "Mag tape ioctl command: MTIOCRDFTSEG");
+	if (zft_qic_mode) {
+		TRACE_ABORT(-EACCES, ft_t_info,
+			    "driver needs to be in raw mode for this ioctl");
+	} 
+	if (arg_size != sizeof(struct mtftseg)) {
+		TRACE_ABORT(-EINVAL, ft_t_info, "bad argument size: %d",
+			    arg_size);
+	}
+	if (zft_offline) {
+		TRACE_EXIT -ENXIO;
+	}
+	if (mtftseg->mt_mode != FT_RD_SINGLE &&
+	    mtftseg->mt_mode != FT_RD_AHEAD) {
+		TRACE_ABORT(-EINVAL, ft_t_info, "invalid read mode");
+	}
+	if (!ft_formatted) {
+		TRACE_EXIT -EACCES; /* -ENXIO ? */
+
+	}
+	if (!zft_header_read) {
+		TRACE_CATCH(zft_def_idle_state(),);
+	}
+	if (mtftseg->mt_segno > ft_last_data_segment) {
+		TRACE_ABORT(-EINVAL, ft_t_info, "segment number is too large");
+	}
+	mtftseg->mt_result = ftape_read_segment(mtftseg->mt_segno,
+						zft_deblock_buf,
+						mtftseg->mt_mode);
+	if (mtftseg->mt_result < 0) {
+		/*  a negativ result is not an ioctl error. if
+		 *  the user wants to read damaged tapes,
+		 *  it's up to her/him
+		 */
+		TRACE_EXIT 0;
+	}
+	if (copy_to_user(mtftseg->mt_data,
+			 zft_deblock_buf,
+			 mtftseg->mt_result) != 0) {
+		TRACE_EXIT -EFAULT;
+	}
+	TRACE_EXIT 0;
+}
+#endif
+
+#ifdef MTIOCWRFTSEG
+/*
+ *  write a floppy tape segment. This version features writing of
+ *  deleted address marks, and gracefully ignores the (software)
+ *  ft_formatted flag to support writing of header segments after
+ *  formatting.
+ */
+static int mtiocwrftseg(struct mtftseg * mtftseg, int arg_size)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE(ft_t_noise, "Mag tape ioctl command: MTIOCWRFTSEG");
+	if (zft_write_protected || zft_qic_mode) {
+		TRACE_EXIT -EACCES;
+	} 
+	if (arg_size != sizeof(struct mtftseg)) {
+		TRACE_ABORT(-EINVAL, ft_t_info, "bad argument size: %d",
+			    arg_size);
+	}
+	if (zft_offline) {
+		TRACE_EXIT -ENXIO;
+	}
+	if (mtftseg->mt_mode != FT_WR_ASYNC   && 
+	    mtftseg->mt_mode != FT_WR_MULTI   &&
+	    mtftseg->mt_mode != FT_WR_SINGLE  &&
+	    mtftseg->mt_mode != FT_WR_DELETE) {
+		TRACE_ABORT(-EINVAL, ft_t_info, "invalid write mode");
+	}
+	/*
+	 *  We don't check for ft_formatted, because this gives
+	 *  only the software status of the driver.
+	 *
+	 *  We assume that the user knows what it is
+	 *  doing. And rely on the low level stuff to fail
+	 *  when the tape isn't formatted. We only make sure
+	 *  that The header segment buffer is allocated,
+	 *  because it holds the bad sector map.
+	 */
+	if (zft_hseg_buf == NULL) {
+		TRACE_EXIT -ENXIO;
+	}
+	if (mtftseg->mt_mode != FT_WR_DELETE) {
+		if (copy_from_user(zft_deblock_buf, 
+				   mtftseg->mt_data,
+				   FT_SEGMENT_SIZE) != 0) {
+			TRACE_EXIT -EFAULT;
+		}
+	}
+	mtftseg->mt_result = ftape_write_segment(mtftseg->mt_segno, 
+						 zft_deblock_buf,
+						 mtftseg->mt_mode);
+	if (mtftseg->mt_result >= 0 && mtftseg->mt_mode == FT_WR_SINGLE) {
+		/*  
+		 *  a negativ result is not an ioctl error. if
+		 *  the user wants to write damaged tapes,
+		 *  it's up to her/him
+		 */
+		if ((result = ftape_loop_until_writes_done()) < 0) {
+			mtftseg->mt_result = result;
+		}
+	}
+	TRACE_EXIT 0;
+}
+#endif
+  
+#ifdef MTIOCVOLINFO
+/*
+ *  get information about volume positioned at.
+ */
+static int mtiocvolinfo(struct mtvolinfo *volinfo, int arg_size)
+{
+	const zft_volinfo *volume;
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE(ft_t_noise, "Mag tape ioctl command: MTIOCVOLINFO");
+	if (arg_size != sizeof(struct mtvolinfo)) {
+		TRACE_ABORT(-EINVAL,
+			    ft_t_info, "bad argument size: %d", arg_size);
+	}
+	if (zft_offline) {
+		TRACE_EXIT -ENXIO;
+	}
+	if (!ft_formatted) {
+		TRACE_EXIT -EACCES;
+	}
+	TRACE_CATCH(zft_def_idle_state(),);
+	volume = zft_find_volume(zft_pos.seg_pos);
+	volinfo->mt_volno   = volume->count;
+	volinfo->mt_blksz   = volume->blk_sz == 1 ? 0 : volume->blk_sz;
+	volinfo->mt_size    = volume->size >> 10;
+	volinfo->mt_rawsize = ((zft_calc_tape_pos(volume->end_seg + 1) >> 10) -
+			       (zft_calc_tape_pos(volume->start_seg) >> 10));
+	volinfo->mt_cmpr    = volume->use_compression;
+	TRACE_EXIT 0;
+}
+#endif
+
+#ifdef ZFT_OBSOLETE  
+static int mtioc_zftape_getblksz(struct mtblksz *blksz, int arg_size)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE(ft_t_noise, "\n"
+	      KERN_INFO "Mag tape ioctl command: MTIOC_ZTAPE_GETBLKSZ\n"
+	      KERN_INFO "This ioctl is here merely for compatibility.\n"
+	      KERN_INFO "Please use MTIOCVOLINFO instead");
+	if (arg_size != sizeof(struct mtblksz)) {
+		TRACE_ABORT(-EINVAL,
+			    ft_t_info, "bad argument size: %d", arg_size);
+	}
+	if (zft_offline) {
+		TRACE_EXIT -ENXIO;
+	}
+	if (!ft_formatted) {
+		TRACE_EXIT -EACCES;
+	}
+	TRACE_CATCH(zft_def_idle_state(),);
+	blksz->mt_blksz = zft_find_volume(zft_pos.seg_pos)->blk_sz;
+	TRACE_EXIT 0;
+}
+#endif
+
+#ifdef MTIOCGETSIZE
+/*
+ *  get the capacity of the tape cartridge.
+ */
+static int mtiocgetsize(struct mttapesize *size, int arg_size)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE(ft_t_noise, "Mag tape ioctl command: MTIOC_ZFTAPE_GETSIZE");
+	if (arg_size != sizeof(struct mttapesize)) {
+		TRACE_ABORT(-EINVAL,
+			    ft_t_info, "bad argument size: %d", arg_size);
+	}
+	if (zft_offline) {
+		TRACE_EXIT -ENXIO;
+	}
+	if (!ft_formatted) {
+		TRACE_EXIT -EACCES;
+	}
+	TRACE_CATCH(zft_def_idle_state(),);
+	size->mt_capacity = (unsigned int)(zft_capacity>>10);
+	size->mt_used     = (unsigned int)(zft_get_eom_pos()>>10);
+	TRACE_EXIT 0;
+}
+#endif
+
+static int mtiocpos(struct mtpos *mtpos, int arg_size)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE(ft_t_noise, "Mag tape ioctl command: MTIOCPOS");
+	if (arg_size != sizeof(struct mtpos)) {
+		TRACE_ABORT(-EINVAL,
+			    ft_t_info, "bad argument size: %d", arg_size);
+	}
+	result = mt_tell((int *)&mtpos->mt_blkno);
+	TRACE_EXIT result;
+}
+
+#ifdef MTIOCFTFORMAT
+/*
+ * formatting of floppy tape cartridges. This is intended to be used
+ * together with the MTIOCFTCMD ioctl and the new mmap feature 
+ */
+
+/* 
+ *  This function uses ftape_decode_header_segment() to inform the low
+ *  level ftape module about the new parameters.
+ *
+ *  It erases the hseg_buf. The calling process must specify all
+ *  parameters to assure proper operation.
+ *
+ *  return values: -EINVAL - wrong argument size
+ *                 -EINVAL - if ftape_decode_header_segment() failed.
+ */
+static int set_format_parms(struct ftfmtparms *p, __u8 *hseg_buf)
+{
+	ft_trace_t old_level = TRACE_LEVEL;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_noise, "MTIOCFTFORMAT operation FTFMT_SETPARMS");
+	memset(hseg_buf, 0, FT_SEGMENT_SIZE);
+	PUT4(hseg_buf, FT_SIGNATURE, FT_HSEG_MAGIC);
+
+	/*  fill in user specified parameters
+	 */
+	hseg_buf[FT_FMT_CODE] = (__u8)p->ft_fmtcode;
+	PUT2(hseg_buf, FT_SPT, p->ft_spt);
+	hseg_buf[FT_TPC]      = (__u8)p->ft_tpc;
+	hseg_buf[FT_FHM]      = (__u8)p->ft_fhm;
+	hseg_buf[FT_FTM]      = (__u8)p->ft_ftm;
+
+	/*  fill in sane defaults to make ftape happy.
+	 */ 
+	hseg_buf[FT_FSM] = (__u8)128; /* 128 is hard wired all over ftape */
+	if (p->ft_fmtcode == fmt_big) {
+		PUT4(hseg_buf, FT_6_HSEG_1,   0);
+		PUT4(hseg_buf, FT_6_HSEG_2,   1);
+		PUT4(hseg_buf, FT_6_FRST_SEG, 2);
+		PUT4(hseg_buf, FT_6_LAST_SEG, p->ft_spt * p->ft_tpc - 1);
+	} else {
+		PUT2(hseg_buf, FT_HSEG_1,    0);
+		PUT2(hseg_buf, FT_HSEG_2,    1);
+		PUT2(hseg_buf, FT_FRST_SEG,  2);
+		PUT2(hseg_buf, FT_LAST_SEG, p->ft_spt * p->ft_tpc - 1);
+	}
+
+	/*  Synchronize with the low level module. This is particularly
+	 *  needed for unformatted cartridges as the QIC std was previously 
+	 *  unknown BUT is needed to set data rate and to calculate timeouts.
+	 */
+	TRACE_CATCH(ftape_calibrate_data_rate(p->ft_qicstd&QIC_TAPE_STD_MASK),
+		    _res = -EINVAL);
+
+	/*  The following will also recalcualte the timeouts for the tape
+	 *  length and QIC std we want to format to.
+	 *  abort with -EINVAL rather than -EIO
+	 */
+	SET_TRACE_LEVEL(ft_t_warn);
+	TRACE_CATCH(ftape_decode_header_segment(hseg_buf),
+		    SET_TRACE_LEVEL(old_level); _res = -EINVAL);
+	SET_TRACE_LEVEL(old_level);
+	TRACE_EXIT 0;
+}
+
+/*
+ *  Return the internal SOFTWARE status of the kernel driver. This does
+ *  NOT query the tape drive about its status.
+ */
+static int get_format_parms(struct ftfmtparms *p, __u8 *hseg_buffer)
+{
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_noise, "MTIOCFTFORMAT operation FTFMT_GETPARMS");
+	p->ft_qicstd  = ft_qic_std;
+	p->ft_fmtcode = ft_format_code;
+	p->ft_fhm     = hseg_buffer[FT_FHM];
+	p->ft_ftm     = hseg_buffer[FT_FTM];
+	p->ft_spt     = ft_segments_per_track;
+	p->ft_tpc     = ft_tracks_per_tape;
+	TRACE_EXIT 0;
+}
+
+static int mtiocftformat(struct mtftformat *mtftformat, int arg_size)
+{
+	int result;
+	union fmt_arg *arg = &mtftformat->fmt_arg;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_noise, "Mag tape ioctl command: MTIOCFTFORMAT");
+	if (zft_offline) {
+		if (ft_no_tape) {
+			TRACE_ABORT(-ENXIO, ft_t_info, "no tape present");
+		} else {
+			TRACE_ABORT(-ENXIO, ft_t_info, "drive is offline");
+		}
+	}
+	if (zft_qic_mode) {
+		TRACE_ABORT(-EACCES, ft_t_info,
+			    "driver needs to be in raw mode for this ioctl");
+	} 
+	if (zft_hseg_buf == NULL) {
+		TRACE_CATCH(zft_vcalloc_once(&zft_hseg_buf, FT_SEGMENT_SIZE),);
+	}
+	zft_header_read = 0;
+	switch(mtftformat->fmt_op) {
+	case FTFMT_SET_PARMS:
+		TRACE_CATCH(set_format_parms(&arg->fmt_parms, zft_hseg_buf),);
+		TRACE_EXIT 0;
+	case FTFMT_GET_PARMS:
+		TRACE_CATCH(get_format_parms(&arg->fmt_parms, zft_hseg_buf),);
+		TRACE_EXIT 0;
+	case FTFMT_FORMAT_TRACK:
+		if ((ft_formatted && zft_check_write_access(&zft_pos) < 0) ||
+		    (!ft_formatted && zft_write_protected)) {
+			TRACE_ABORT(-EACCES, ft_t_info, "Write access denied");
+		}
+		TRACE_CATCH(ftape_format_track(arg->fmt_track.ft_track,
+					       arg->fmt_track.ft_gap3),);
+		TRACE_EXIT 0;
+	case FTFMT_STATUS:
+		TRACE_CATCH(ftape_format_status(&arg->fmt_status.ft_segment),);
+		TRACE_EXIT 0;
+	case FTFMT_VERIFY:
+		TRACE_CATCH(ftape_verify_segment(arg->fmt_verify.ft_segment,
+				(SectorMap *)&arg->fmt_verify.ft_bsm),);
+		TRACE_EXIT 0;
+	default:
+		TRACE_ABORT(-EINVAL, ft_t_err, "Invalid format operation");
+	}
+	TRACE_EXIT result;
+}
+#endif
+
+#ifdef MTIOCFTCMD
+/*
+ *  send a QIC-117 command to the drive, with optional timeouts,
+ *  parameter and result bits. This is intended to be used together
+ *  with the formatting ioctl.
+ */
+static int mtiocftcmd(struct mtftcmd *ftcmd, int arg_size)
+{
+	int i;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_noise, "Mag tape ioctl command: MTIOCFTCMD");
+	if (!capable(CAP_SYS_ADMIN)) {
+		TRACE_ABORT(-EPERM, ft_t_info,
+			    "need CAP_SYS_ADMIN capability to send raw qic-117 commands");
+	}
+	if (zft_qic_mode) {
+		TRACE_ABORT(-EACCES, ft_t_info,
+			    "driver needs to be in raw mode for this ioctl");
+	} 
+	if (arg_size != sizeof(struct mtftcmd)) {
+		TRACE_ABORT(-EINVAL,
+			    ft_t_info, "bad argument size: %d", arg_size);
+	}
+	if (ftcmd->ft_wait_before) {
+		TRACE_CATCH(ftape_ready_wait(ftcmd->ft_wait_before,
+					     &ftcmd->ft_status),);
+	}
+	if (ftcmd->ft_status & QIC_STATUS_ERROR)
+		goto ftmtcmd_error;
+	if (ftcmd->ft_result_bits != 0) {
+		TRACE_CATCH(ftape_report_operation(&ftcmd->ft_result,
+						   ftcmd->ft_cmd,
+						   ftcmd->ft_result_bits),);
+	} else {
+		TRACE_CATCH(ftape_command(ftcmd->ft_cmd),);
+		if (ftcmd->ft_status & QIC_STATUS_ERROR)
+			goto ftmtcmd_error;
+		for (i = 0; i < ftcmd->ft_parm_cnt; i++) {
+			TRACE_CATCH(ftape_parameter(ftcmd->ft_parms[i]&0x0f),);
+			if (ftcmd->ft_status & QIC_STATUS_ERROR)
+				goto ftmtcmd_error;
+		}
+	}
+	if (ftcmd->ft_wait_after != 0) {
+		TRACE_CATCH(ftape_ready_wait(ftcmd->ft_wait_after,
+					     &ftcmd->ft_status),);
+	}
+ftmtcmd_error:	       
+	if (ftcmd->ft_status & QIC_STATUS_ERROR) {
+		TRACE(ft_t_noise, "error status set");
+		TRACE_CATCH(ftape_report_error(&ftcmd->ft_error,
+					       &ftcmd->ft_cmd, 1),);
+	}
+	TRACE_EXIT 0; /* this is not an i/o error */
+}
+#endif
+
+/*  IOCTL routine called by kernel-interface code
+ */
+int _zft_ioctl(unsigned int command, void __user * arg)
+{
+	int result;
+	union { struct mtop       mtop;
+		struct mtget      mtget;
+		struct mtpos      mtpos;
+#ifdef MTIOCRDFTSEG
+		struct mtftseg    mtftseg;
+#endif
+#ifdef MTIOCVOLINFO
+		struct mtvolinfo  mtvolinfo;
+#endif
+#ifdef MTIOCGETSIZE
+		struct mttapesize mttapesize;
+#endif
+#ifdef MTIOCFTFORMAT
+		struct mtftformat mtftformat;
+#endif
+#ifdef ZFT_OBSOLETE
+		struct mtblksz mtblksz;
+#endif
+#ifdef MTIOCFTCMD
+		struct mtftcmd mtftcmd;
+#endif
+	} krnl_arg;
+	int arg_size = _IOC_SIZE(command);
+	int dir = _IOC_DIR(command);
+	TRACE_FUN(ft_t_flow);
+
+	/* This check will only catch arguments that are too large !
+	 */
+	if (dir & (_IOC_READ | _IOC_WRITE) && arg_size > sizeof(krnl_arg)) {
+		TRACE_ABORT(-EINVAL,
+			    ft_t_info, "bad argument size: %d", arg_size);
+	}
+	if (dir & _IOC_WRITE) {
+		if (copy_from_user(&krnl_arg, arg, arg_size) != 0) {
+			TRACE_EXIT -EFAULT;
+		}
+	}
+	TRACE(ft_t_flow, "called with ioctl command: 0x%08x", command);
+	switch (command) {
+	case MTIOCTOP:
+		result = mtioctop(&krnl_arg.mtop, arg_size);
+		break;
+	case MTIOCGET:
+		result = mtiocget(&krnl_arg.mtget, arg_size);
+		break;
+	case MTIOCPOS:
+		result = mtiocpos(&krnl_arg.mtpos, arg_size);
+		break;
+#ifdef MTIOCVOLINFO
+	case MTIOCVOLINFO:
+		result = mtiocvolinfo(&krnl_arg.mtvolinfo, arg_size);
+		break;
+#endif
+#ifdef ZFT_OBSOLETE
+	case MTIOC_ZFTAPE_GETBLKSZ:
+		result = mtioc_zftape_getblksz(&krnl_arg.mtblksz, arg_size);
+		break;
+#endif
+#ifdef MTIOCRDFTSEG
+	case MTIOCRDFTSEG: /* read a segment via ioctl */
+		result = mtiocrdftseg(&krnl_arg.mtftseg, arg_size);
+		break;
+#endif
+#ifdef MTIOCWRFTSEG
+	case MTIOCWRFTSEG: /* write a segment via ioctl */
+		result = mtiocwrftseg(&krnl_arg.mtftseg, arg_size);
+		break;
+#endif
+#ifdef MTIOCGETSIZE
+	case MTIOCGETSIZE:
+		result = mtiocgetsize(&krnl_arg.mttapesize, arg_size);
+		break;
+#endif
+#ifdef MTIOCFTFORMAT
+	case MTIOCFTFORMAT:
+		result = mtiocftformat(&krnl_arg.mtftformat, arg_size);
+		break;
+#endif
+#ifdef MTIOCFTCMD
+	case MTIOCFTCMD:
+		result = mtiocftcmd(&krnl_arg.mtftcmd, arg_size);
+		break;
+#endif
+	default:
+		result = -EINVAL;
+		break;
+	}
+	if ((result >= 0) && (dir & _IOC_READ)) {
+		if (copy_to_user(arg, &krnl_arg, arg_size) != 0) {
+			TRACE_EXIT -EFAULT;
+		}
+	}
+	TRACE_EXIT result;
+}
diff --git a/drivers/char/ftape/zftape/zftape-ctl.h b/drivers/char/ftape/zftape/zftape-ctl.h
new file mode 100644
index 0000000..4141598
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-ctl.h
@@ -0,0 +1,59 @@
+#ifndef _ZFTAPE_CTL_H
+#define _ZFTAPE_CTL_H
+
+/*
+ * Copyright (C) 1996, 1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version. 
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-ctl.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:19:02 $
+ *
+ *      This file contains the non-standard IOCTL related definitions
+ *      for the QIC-40/80 floppy-tape driver for Linux.
+ */
+
+#include <linux/config.h>
+#include <linux/ioctl.h>
+#include <linux/mtio.h>
+
+#include "../zftape/zftape-rw.h"
+
+#ifdef CONFIG_ZFTAPE_MODULE
+#define ftape_status (*zft_status)
+#endif
+
+extern int zft_offline;
+extern int zft_mt_compression;
+extern int zft_write_protected;
+extern int zft_header_read;
+extern unsigned int zft_unit;
+extern int zft_resid;
+
+extern void zft_reset_position(zft_position *pos);
+extern int  zft_check_write_access(zft_position *pos);
+extern int  zft_def_idle_state(void);
+
+/*  hooks for the VFS interface 
+ */
+extern int  _zft_open(unsigned int dev_minor, unsigned int access_mode);
+extern int  _zft_close(void);
+extern int  _zft_ioctl(unsigned int command, void __user *arg);
+#endif
+
+
+
diff --git a/drivers/char/ftape/zftape/zftape-eof.c b/drivers/char/ftape/zftape/zftape-eof.c
new file mode 100644
index 0000000..dcadcae
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-eof.c
@@ -0,0 +1,199 @@
+/*
+ *   I use these routines just to decide when I have to fake a 
+ *   volume-table to preserve compatibility to original ftape.
+ */
+/*
+ *      Copyright (C) 1994-1995 Bas Laarhoven.
+ *      
+ *      Modified for zftape 1996, 1997 Claus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-eof.c,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:19:02 $
+ *
+ *      This file contains the eof mark handling code
+ *      for the QIC-40/80 floppy-tape driver for Linux.
+ */
+
+#include <linux/string.h>
+#include <linux/errno.h>
+
+#include <linux/zftape.h>
+
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-rw.h"
+#include "../zftape/zftape-eof.h"
+
+/*      Global vars.
+ */
+
+/* a copy of the failed sector log from the header segment.
+ */
+eof_mark_union *zft_eof_map;
+
+/* number of eof marks (entries in bad sector log) on tape.
+ */
+int zft_nr_eof_marks = -1;
+
+
+/*      Local vars.
+ */
+
+static char linux_tape_label[] = "Linux raw format V";
+enum { 
+	min_fmt_version = 1, max_fmt_version = 2 
+};
+static unsigned ftape_fmt_version = 0;
+
+
+/* Ftape (mis)uses the bad sector log to record end-of-file marks.
+ * Initially (when the tape is erased) all entries in the bad sector
+ * log are added to the tape's bad sector map. The bad sector log then
+ * is cleared.
+ *
+ * The bad sector log normally contains entries of the form: 
+ * even 16-bit word: segment number of bad sector 
+ * odd 16-bit word: encoded date
+ * There can be a total of 448 entries (1792 bytes).
+ *
+ * My guess is that no program is using this bad sector log (the *
+ * format seems useless as there is no indication of the bad sector
+ * itself, only the segment) However, if any program does use the bad
+ * sector log, the format used by ftape will let the program think
+ * there are some bad sectors and no harm is done.
+ *  
+ * The eof mark entries that ftape stores in the bad sector log: even
+ * 16-bit word: segment number of eof mark odd 16-bit word: sector
+ * number of eof mark [1..32]
+ *  
+ * The zft_eof_map as maintained is a sorted list of eof mark entries.
+ *
+ *
+ * The tape name field in the header segments is used to store a linux
+ * tape identification string and a version number.  This way the tape
+ * can be recognized as a Linux raw format tape when using tools under
+ * other OS's.
+ *
+ * 'Wide' QIC tapes (format code 4) don't have a failed sector list
+ * anymore. That space is used for the (longer) bad sector map that
+ * now is a variable length list too.  We now store our end-of-file
+ * marker list after the bad-sector-map on tape. The list is delimited
+ * by a (__u32) 0 entry.
+ */
+
+int zft_ftape_validate_label(char *label)
+{
+	static char tmp_label[45];
+	int result = 0;
+	TRACE_FUN(ft_t_any);
+	
+	memcpy(tmp_label, label, FT_LABEL_SZ);
+	tmp_label[FT_LABEL_SZ] = '\0';
+	TRACE(ft_t_noise, "tape  label = `%s'", tmp_label);
+	ftape_fmt_version = 0;
+	if (memcmp(label, linux_tape_label, strlen(linux_tape_label)) == 0) {
+		int pos = strlen(linux_tape_label);
+		while (label[pos] >= '0' && label[pos] <= '9') {
+			ftape_fmt_version *= 10;
+			ftape_fmt_version = label[ pos++] - '0';
+		}
+		result = (ftape_fmt_version >= min_fmt_version &&
+			  ftape_fmt_version <= max_fmt_version);
+	}
+	TRACE(ft_t_noise, "format version = %d", ftape_fmt_version);
+	TRACE_EXIT result;
+}
+
+static __u8 * find_end_of_eof_list(__u8 * ptr, __u8 * limit)
+{
+	while (ptr + 3 < limit) {
+
+		if (get_unaligned((__u32*)ptr)) {
+			ptr += sizeof(__u32);
+		} else {
+			return ptr;
+		}
+	}
+	return NULL;
+}
+
+void zft_ftape_extract_file_marks(__u8* address)
+{
+	int i;
+	TRACE_FUN(ft_t_any);
+	
+	zft_eof_map = NULL;
+	if (ft_format_code == fmt_var || ft_format_code == fmt_big) {
+		__u8* end;
+		__u8* start = ftape_find_end_of_bsm_list(address);
+
+		zft_nr_eof_marks = 0;
+		if (start) {
+			start += 3; /* skip end of list mark */
+			end = find_end_of_eof_list(start, 
+						   address + FT_SEGMENT_SIZE);
+			if (end && end - start <= FT_FSL_SIZE) {
+				zft_nr_eof_marks = ((end - start) / 
+						    sizeof(eof_mark_union));
+				zft_eof_map = (eof_mark_union *)start;
+			} else {
+				TRACE(ft_t_err,
+				      "EOF Mark List is too long or damaged!");
+			}
+		} else {
+			TRACE(ft_t_err, 
+			      "Bad Sector List is too long or damaged !");
+		}
+	} else {
+		zft_eof_map = (eof_mark_union *)&address[FT_FSL];
+		zft_nr_eof_marks = GET2(address, FT_FSL_CNT);
+	}
+	TRACE(ft_t_noise, "number of file marks: %d", zft_nr_eof_marks);
+	if (ftape_fmt_version == 1) {
+		TRACE(ft_t_info, "swapping version 1 fields");
+		/* version 1 format uses swapped sector and segment
+		 * fields, correct that !  
+		 */
+		for (i = 0; i < zft_nr_eof_marks; ++i) {
+			__u16 tmp = GET2(&zft_eof_map[i].mark.segment,0);
+			PUT2(&zft_eof_map[i].mark.segment, 0, 
+			     GET2(&zft_eof_map[i].mark.date,0));
+			PUT2(&zft_eof_map[i].mark.date, 0, tmp);
+		}
+	}
+	for (i = 0; i < zft_nr_eof_marks; ++i) {
+		TRACE(ft_t_noise, "eof mark: %5d/%2d",
+			GET2(&zft_eof_map[i].mark.segment, 0), 
+			GET2(&zft_eof_map[i].mark.date,0));
+	}
+	TRACE_EXIT;
+}
+
+void zft_clear_ftape_file_marks(void)
+{
+	TRACE_FUN(ft_t_flow);
+	/*  Clear failed sector log: remove all tape marks. We
+	 *  don't use old ftape-style EOF-marks.
+	 */
+	TRACE(ft_t_info, "Clearing old ftape's eof map");
+	memset(zft_eof_map, 0, zft_nr_eof_marks * sizeof(__u32));
+	zft_nr_eof_marks = 0;
+	PUT2(zft_hseg_buf, FT_FSL_CNT, 0); /* nr of eof-marks */
+	zft_header_changed = 1;
+	zft_update_label(zft_hseg_buf);
+	TRACE_EXIT;
+}
diff --git a/drivers/char/ftape/zftape/zftape-eof.h b/drivers/char/ftape/zftape/zftape-eof.h
new file mode 100644
index 0000000..26568c2
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-eof.h
@@ -0,0 +1,52 @@
+#ifndef _ZFTAPE_EOF_H
+#define _ZFTAPE_EOF_H
+
+/*
+ * Copyright (C) 1994-1995 Bas Laarhoven.
+ * adaptaed for zftape 1996, 1997 by Claus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-eof.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:19:03 $
+ *
+ *      Definitions and declarations for the end of file markers
+ *      for the QIC-40/80 floppy-tape driver for Linux.
+ */
+
+#include <linux/ftape-header-segment.h>
+#include "../zftape/zftape-buffers.h"
+/*  failed sector log size (only used if format code != 4).
+ */
+
+typedef union {
+	ft_fsl_entry mark;
+	__u32 entry;
+} eof_mark_union;
+ 
+/*      ftape-eof.c defined global vars.
+ */
+extern int zft_nr_eof_marks;
+extern eof_mark_union *zft_eof_map;
+
+/*      ftape-eof.c defined global functions.
+ */
+extern void zft_ftape_extract_file_marks(__u8* address);
+extern int  zft_ftape_validate_label(char* label);
+extern void zft_clear_ftape_file_marks(void);
+
+#endif
diff --git a/drivers/char/ftape/zftape/zftape-init.c b/drivers/char/ftape/zftape/zftape-init.c
new file mode 100644
index 0000000..dbac7e5
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-init.c
@@ -0,0 +1,403 @@
+/*
+ *      Copyright (C) 1996, 1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ *      This file contains the code that registers the zftape frontend 
+ *      to the ftape floppy tape driver for Linux
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/major.h>
+#include <linux/slab.h>
+#ifdef CONFIG_KMOD
+#include <linux/kmod.h>
+#endif
+#include <linux/fcntl.h>
+#include <linux/smp_lock.h>
+#include <linux/devfs_fs_kernel.h>
+
+#include <linux/zftape.h>
+#include <linux/init.h>
+#include <linux/device.h>
+
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-read.h"
+#include "../zftape/zftape-write.h"
+#include "../zftape/zftape-ctl.h"
+#include "../zftape/zftape-buffers.h"
+
+MODULE_AUTHOR("(c) 1996, 1997 Claus-Justus Heine "
+	      "(claus@momo.math.rwth-aachen.de)");
+MODULE_DESCRIPTION(ZFTAPE_VERSION " - "
+		   "VFS interface for the Linux floppy tape driver. "
+		   "Support for QIC-113 compatible volume table "
+		   "and builtin compression (lzrw3 algorithm)");
+MODULE_SUPPORTED_DEVICE("char-major-27");
+MODULE_LICENSE("GPL");
+
+/*      Global vars.
+ */
+struct zft_cmpr_ops *zft_cmpr_ops = NULL;
+const ftape_info *zft_status;
+
+/*      Local vars.
+ */
+static unsigned long busy_flag;
+
+static sigset_t orig_sigmask;
+
+/*  the interface to the kernel vfs layer
+ */
+
+/* Note about llseek():
+ *
+ * st.c and tpqic.c update fp->f_pos but don't implment llseek() and
+ * initialize the llseek component of the file_ops struct with NULL.
+ * This means that the user will get the default seek, but the tape
+ * device will not respect the new position, but happily read from the
+ * old position. Think a zftape specific llseek() function would be
+ * better, returning -ESPIPE. TODO.
+ */
+
+static int  zft_open (struct inode *ino, struct file *filep);
+static int zft_close(struct inode *ino, struct file *filep);
+static int  zft_ioctl(struct inode *ino, struct file *filep,
+		      unsigned int command, unsigned long arg);
+static int  zft_mmap(struct file *filep, struct vm_area_struct *vma);
+static ssize_t zft_read (struct file *fp, char __user *buff,
+			 size_t req_len, loff_t *ppos);
+static ssize_t zft_write(struct file *fp, const char __user *buff,
+			 size_t req_len, loff_t *ppos);
+
+static struct file_operations zft_cdev =
+{
+	.owner		= THIS_MODULE,
+	.read		= zft_read,
+	.write		= zft_write,
+	.ioctl		= zft_ioctl,
+	.mmap		= zft_mmap,
+	.open		= zft_open,
+	.release	= zft_close,
+};
+
+static struct class_simple *zft_class;
+
+/*      Open floppy tape device
+ */
+static int zft_open(struct inode *ino, struct file *filep)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	nonseekable_open(ino, filep);
+	TRACE(ft_t_flow, "called for minor %d", iminor(ino));
+	if ( test_and_set_bit(0,&busy_flag) ) {
+		TRACE_ABORT(-EBUSY, ft_t_warn, "failed: already busy");
+	}
+	if ((iminor(ino) & ~(ZFT_MINOR_OP_MASK | FTAPE_NO_REWIND))
+	     > 
+	    FTAPE_SEL_D) {
+		clear_bit(0,&busy_flag);
+		TRACE_ABORT(-ENXIO, ft_t_err, "failed: invalid unit nr");
+	}
+	orig_sigmask = current->blocked;
+	sigfillset(&current->blocked);
+	result = _zft_open(iminor(ino), filep->f_flags & O_ACCMODE);
+	if (result < 0) {
+		current->blocked = orig_sigmask; /* restore mask */
+		clear_bit(0,&busy_flag);
+		TRACE_ABORT(result, ft_t_err, "_ftape_open failed");
+	} else {
+		/* Mask signals that will disturb proper operation of the
+		 * program that is calling.
+		 */
+		current->blocked = orig_sigmask;
+		sigaddsetmask (&current->blocked, _DO_BLOCK);
+		TRACE_EXIT 0;
+	}
+}
+
+/*      Close floppy tape device
+ */
+static int zft_close(struct inode *ino, struct file *filep)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	if ( !test_bit(0,&busy_flag) || iminor(ino) != zft_unit) {
+		TRACE(ft_t_err, "failed: not busy or wrong unit");
+		TRACE_EXIT 0;
+	}
+	sigfillset(&current->blocked);
+	result = _zft_close();
+	if (result < 0) {
+		TRACE(ft_t_err, "_zft_close failed");
+	}
+	current->blocked = orig_sigmask; /* restore before open state */
+	clear_bit(0,&busy_flag);
+	TRACE_EXIT 0;
+}
+
+/*      Ioctl for floppy tape device
+ */
+static int zft_ioctl(struct inode *ino, struct file *filep,
+		     unsigned int command, unsigned long arg)
+{
+	int result = -EIO;
+	sigset_t old_sigmask;
+	TRACE_FUN(ft_t_flow);
+
+	if ( !test_bit(0,&busy_flag) || iminor(ino) != zft_unit || ft_failure) {
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "failed: not busy, failure or wrong unit");
+	}
+	old_sigmask = current->blocked; /* save mask */
+	sigfillset(&current->blocked);
+	/* This will work as long as sizeof(void *) == sizeof(long) */
+	result = _zft_ioctl(command, (void __user *) arg);
+	current->blocked = old_sigmask; /* restore mask */
+	TRACE_EXIT result;
+}
+
+/*      Ioctl for floppy tape device
+ */
+static int  zft_mmap(struct file *filep, struct vm_area_struct *vma)
+{
+	int result = -EIO;
+	sigset_t old_sigmask;
+	TRACE_FUN(ft_t_flow);
+
+	if ( !test_bit(0,&busy_flag) || 
+	    iminor(filep->f_dentry->d_inode) != zft_unit || 
+	    ft_failure)
+	{
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "failed: not busy, failure or wrong unit");
+	}
+	old_sigmask = current->blocked; /* save mask */
+	sigfillset(&current->blocked);
+	if ((result = ftape_mmap(vma)) >= 0) {
+#ifndef MSYNC_BUG_WAS_FIXED
+		static struct vm_operations_struct dummy = { NULL, };
+		vma->vm_ops = &dummy;
+#endif
+	}
+	current->blocked = old_sigmask; /* restore mask */
+	TRACE_EXIT result;
+}
+
+/*      Read from floppy tape device
+ */
+static ssize_t zft_read(struct file *fp, char __user *buff,
+			size_t req_len, loff_t *ppos)
+{
+	int result = -EIO;
+	sigset_t old_sigmask;
+	struct inode *ino = fp->f_dentry->d_inode;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_data_flow, "called with count: %ld", (unsigned long)req_len);
+	if (!test_bit(0,&busy_flag)  || iminor(ino) != zft_unit || ft_failure) {
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "failed: not busy, failure or wrong unit");
+	}
+	old_sigmask = current->blocked; /* save mask */
+	sigfillset(&current->blocked);
+	result = _zft_read(buff, req_len);
+	current->blocked = old_sigmask; /* restore mask */
+	TRACE(ft_t_data_flow, "return with count: %d", result);
+	TRACE_EXIT result;
+}
+
+/*      Write to tape device
+ */
+static ssize_t zft_write(struct file *fp, const char __user *buff,
+			 size_t req_len, loff_t *ppos)
+{
+	int result = -EIO;
+	sigset_t old_sigmask;
+	struct inode *ino = fp->f_dentry->d_inode;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_flow, "called with count: %ld", (unsigned long)req_len);
+	if (!test_bit(0,&busy_flag) || iminor(ino) != zft_unit || ft_failure) {
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "failed: not busy, failure or wrong unit");
+	}
+	old_sigmask = current->blocked; /* save mask */
+	sigfillset(&current->blocked);
+	result = _zft_write(buff, req_len);
+	current->blocked = old_sigmask; /* restore mask */
+	TRACE(ft_t_data_flow, "return with count: %d", result);
+	TRACE_EXIT result;
+}
+
+/*                    END OF VFS INTERFACE 
+ *          
+ *****************************************************************************/
+
+/*  driver/module initialization
+ */
+
+/*  the compression module has to call this function to hook into the zftape 
+ *  code
+ */
+int zft_cmpr_register(struct zft_cmpr_ops *new_ops)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	if (zft_cmpr_ops != NULL) {
+		TRACE_EXIT -EBUSY;
+	} else {
+		zft_cmpr_ops = new_ops;
+		TRACE_EXIT 0;
+	}
+}
+
+/*  lock the zft-compressor() module.
+ */
+int zft_cmpr_lock(int try_to_load)
+{
+	if (zft_cmpr_ops == NULL) {
+#ifdef CONFIG_KMOD
+		if (try_to_load) {
+			request_module("zft-compressor");
+			if (zft_cmpr_ops == NULL) {
+				return -ENOSYS;
+			}
+		} else {
+			return -ENOSYS;
+		}
+#else
+		return -ENOSYS;
+#endif
+	}
+	(*zft_cmpr_ops->lock)();
+	return 0;
+}
+
+#ifdef CONFIG_ZFT_COMPRESSOR
+extern int zft_compressor_init(void);
+#endif
+
+/*  Called by modules package when installing the driver or by kernel
+ *  during the initialization phase
+ */
+int __init zft_init(void)
+{
+	int i;
+	TRACE_FUN(ft_t_flow);
+
+#ifdef MODULE
+	printk(KERN_INFO ZFTAPE_VERSION "\n");
+        if (TRACE_LEVEL >= ft_t_info) {
+		printk(
+KERN_INFO
+"(c) 1996, 1997 Claus-Justus Heine (claus@momo.math.rwth-aachen.de)\n"
+KERN_INFO
+"vfs interface for ftape floppy tape driver.\n"
+KERN_INFO
+"Support for QIC-113 compatible volume table, dynamic memory allocation\n"
+KERN_INFO
+"and builtin compression (lzrw3 algorithm).\n");
+        }
+#else /* !MODULE */
+	/* print a short no-nonsense boot message */
+	printk(KERN_INFO ZFTAPE_VERSION "\n");
+#endif /* MODULE */
+	TRACE(ft_t_info, "zft_init @ 0x%p", zft_init);
+	TRACE(ft_t_info,
+	      "installing zftape VFS interface for ftape driver ...");
+	TRACE_CATCH(register_chrdev(QIC117_TAPE_MAJOR, "zft", &zft_cdev),);
+
+	zft_class = class_simple_create(THIS_MODULE, "zft");
+	for (i = 0; i < 4; i++) {
+		class_simple_device_add(zft_class, MKDEV(QIC117_TAPE_MAJOR, i), NULL, "qft%i", i);
+		devfs_mk_cdev(MKDEV(QIC117_TAPE_MAJOR, i),
+				S_IFCHR | S_IRUSR | S_IWUSR,
+				"qft%i", i);
+		class_simple_device_add(zft_class, MKDEV(QIC117_TAPE_MAJOR, i + 4), NULL, "nqft%i", i);
+		devfs_mk_cdev(MKDEV(QIC117_TAPE_MAJOR, i + 4),
+				S_IFCHR | S_IRUSR | S_IWUSR,
+				"nqft%i", i);
+		class_simple_device_add(zft_class, MKDEV(QIC117_TAPE_MAJOR, i + 16), NULL, "zqft%i", i);
+		devfs_mk_cdev(MKDEV(QIC117_TAPE_MAJOR, i + 16),
+				S_IFCHR | S_IRUSR | S_IWUSR,
+				"zqft%i", i);
+		class_simple_device_add(zft_class, MKDEV(QIC117_TAPE_MAJOR, i + 20), NULL, "nzqft%i", i);
+		devfs_mk_cdev(MKDEV(QIC117_TAPE_MAJOR, i + 20),
+				S_IFCHR | S_IRUSR | S_IWUSR,
+				"nzqft%i", i);
+		class_simple_device_add(zft_class, MKDEV(QIC117_TAPE_MAJOR, i + 32), NULL, "rawqft%i", i);
+		devfs_mk_cdev(MKDEV(QIC117_TAPE_MAJOR, i + 32),
+				S_IFCHR | S_IRUSR | S_IWUSR,
+				"rawqft%i", i);
+		class_simple_device_add(zft_class, MKDEV(QIC117_TAPE_MAJOR, i + 36), NULL, "nrawrawqft%i", i);
+		devfs_mk_cdev(MKDEV(QIC117_TAPE_MAJOR, i + 36),
+				S_IFCHR | S_IRUSR | S_IWUSR,
+				"nrawqft%i", i);
+	}
+
+#ifdef CONFIG_ZFT_COMPRESSOR
+	(void)zft_compressor_init();
+#endif
+	zft_status = ftape_get_status(); /*  fetch global data of ftape 
+					  *  hardware driver 
+					  */
+	TRACE_EXIT 0;
+}
+
+
+/* Called by modules package when removing the driver 
+ */
+static void zft_exit(void)
+{
+	int i;
+	TRACE_FUN(ft_t_flow);
+
+	if (unregister_chrdev(QIC117_TAPE_MAJOR, "zft") != 0) {
+		TRACE(ft_t_warn, "failed");
+	} else {
+		TRACE(ft_t_info, "successful");
+	}
+        for (i = 0; i < 4; i++) {
+		devfs_remove("qft%i", i);
+		class_simple_device_remove(MKDEV(QIC117_TAPE_MAJOR, i));
+		devfs_remove("nqft%i", i);
+		class_simple_device_remove(MKDEV(QIC117_TAPE_MAJOR, i + 4));
+		devfs_remove("zqft%i", i);
+		class_simple_device_remove(MKDEV(QIC117_TAPE_MAJOR, i + 16));
+		devfs_remove("nzqft%i", i);
+		class_simple_device_remove(MKDEV(QIC117_TAPE_MAJOR, i + 20));
+		devfs_remove("rawqft%i", i);
+		class_simple_device_remove(MKDEV(QIC117_TAPE_MAJOR, i + 32));
+		devfs_remove("nrawqft%i", i);
+		class_simple_device_remove(MKDEV(QIC117_TAPE_MAJOR, i + 36));
+	}
+	class_simple_destroy(zft_class);
+	zft_uninit_mem(); /* release remaining memory, if any */
+        printk(KERN_INFO "zftape successfully unloaded.\n");
+	TRACE_EXIT;
+}
+
+module_init(zft_init);
+module_exit(zft_exit);
diff --git a/drivers/char/ftape/zftape/zftape-init.h b/drivers/char/ftape/zftape/zftape-init.h
new file mode 100644
index 0000000..937e5d4
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-init.h
@@ -0,0 +1,77 @@
+#ifndef _ZFTAPE_INIT_H
+#define _ZFTAPE_INIT_H
+
+/*
+ * Copyright (C) 1996, 1997 Claus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-init.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:19:05 $
+ *
+ * This file contains definitions and macro for the vfs 
+ * interface defined by zftape
+ *
+ */
+
+#include <linux/ftape-header-segment.h>
+
+#include "../lowlevel/ftape-tracing.h"
+#include "../lowlevel/ftape-ctl.h"
+#include "../lowlevel/ftape-read.h"
+#include "../lowlevel/ftape-write.h"
+#include "../lowlevel/ftape-bsm.h"
+#include "../lowlevel/ftape-io.h"
+#include "../lowlevel/ftape-buffer.h"
+#include "../lowlevel/ftape-format.h"
+
+#include "../zftape/zftape-rw.h"
+
+#ifdef MODULE
+#define ftape_status (*zft_status)
+#endif
+
+extern const  ftape_info *zft_status; /* needed for zftape-vtbl.h */
+
+#include "../zftape/zftape-vtbl.h"
+
+struct zft_cmpr_ops {
+	int (*write)(int *write_cnt,
+		     __u8 *dst_buf, const int seg_sz,
+		     const __u8 __user *src_buf, const int req_len, 
+		     const zft_position *pos, const zft_volinfo *volume);
+	int (*read)(int *read_cnt,
+		    __u8 __user *dst_buf, const int req_len,
+		    const __u8 *src_buf, const int seg_sz,
+		    const zft_position *pos, const zft_volinfo *volume);
+	int (*seek)(unsigned int new_block_pos,
+		    zft_position *pos, const zft_volinfo *volume,
+		    __u8 *buffer);
+	void (*lock)   (void);
+	void (*reset)  (void);
+	void (*cleanup)(void);
+};
+
+extern struct zft_cmpr_ops *zft_cmpr_ops;
+/* zftape-init.c defined global functions.
+ */
+extern int                  zft_cmpr_register(struct zft_cmpr_ops *new_ops);
+extern int                  zft_cmpr_lock(int try_to_load);
+
+#endif
+
+
diff --git a/drivers/char/ftape/zftape/zftape-read.c b/drivers/char/ftape/zftape/zftape-read.c
new file mode 100644
index 0000000..214bf03
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-read.c
@@ -0,0 +1,377 @@
+/*
+ *      Copyright (C) 1996, 1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-read.c,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:19:06 $
+ *
+ *      This file contains the high level reading code
+ *      for the QIC-117 floppy-tape driver for Linux.
+ */
+
+#include <linux/errno.h>
+#include <linux/mm.h>
+
+#include <linux/zftape.h>
+
+#include <asm/uaccess.h>
+
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-eof.h"
+#include "../zftape/zftape-ctl.h"
+#include "../zftape/zftape-write.h"
+#include "../zftape/zftape-read.h"
+#include "../zftape/zftape-rw.h"
+#include "../zftape/zftape-vtbl.h"
+
+/*      Global vars.
+ */
+int zft_just_before_eof;
+
+/*      Local vars.
+ */
+static int buf_len_rd;
+
+void zft_zap_read_buffers(void)
+{
+	buf_len_rd = 0;
+}
+
+int zft_read_header_segments(void)      
+{
+	TRACE_FUN(ft_t_flow);
+
+	zft_header_read = 0;
+	TRACE_CATCH(zft_vmalloc_once(&zft_hseg_buf, FT_SEGMENT_SIZE),);
+	TRACE_CATCH(ftape_read_header_segment(zft_hseg_buf),);
+	TRACE(ft_t_info, "Segments written since first format: %d",
+	      (int)GET4(zft_hseg_buf, FT_SEG_CNT));
+	zft_qic113 = (ft_format_code != fmt_normal &&
+		      ft_format_code != fmt_1100ft &&
+		      ft_format_code != fmt_425ft);
+	TRACE(ft_t_info, "ft_first_data_segment: %d, ft_last_data_segment: %d", 
+	      ft_first_data_segment, ft_last_data_segment);
+	zft_capacity = zft_get_capacity();
+	zft_old_ftape = zft_ftape_validate_label(&zft_hseg_buf[FT_LABEL]);
+	if (zft_old_ftape) {
+		TRACE(ft_t_info, 
+"Found old ftaped tape, emulating eof marks, entering read-only mode");
+		zft_ftape_extract_file_marks(zft_hseg_buf);
+		TRACE_CATCH(zft_fake_volume_headers(zft_eof_map, 
+						    zft_nr_eof_marks),);
+	} else {
+		/* the specs say that the volume table must be
+		 * initialized with zeroes during formatting, so it
+		 * MUST be readable, i.e. contain vaid ECC
+		 * information.  
+		 */
+		TRACE_CATCH(ftape_read_segment(ft_first_data_segment, 
+					       zft_deblock_buf, 
+					       FT_RD_SINGLE),);
+		TRACE_CATCH(zft_extract_volume_headers(zft_deblock_buf),);
+	}
+	zft_header_read = 1;
+	zft_set_flags(zft_unit);
+	zft_reset_position(&zft_pos);
+	TRACE_EXIT 0;
+}
+
+int zft_fetch_segment_fraction(const unsigned int segment, void *buffer,
+			       const ft_read_mode_t read_mode,
+			       const unsigned int start,
+			       const unsigned int size)
+{
+	int seg_sz;
+	TRACE_FUN(ft_t_flow);
+
+	if (segment == zft_deblock_segment) {
+		TRACE(ft_t_data_flow,
+		      "re-using segment %d already in deblock buffer",
+		      segment);
+		seg_sz = zft_get_seg_sz(segment);
+		if (start > seg_sz) {
+			TRACE_ABORT(-EINVAL, ft_t_bug,
+				    "trying to read beyond end of segment:\n"
+				    KERN_INFO "seg_sz : %d\n"
+				    KERN_INFO "start  : %d\n"
+				    KERN_INFO "segment: %d",
+				    seg_sz, start, segment);
+		}
+		if ((start + size) > seg_sz) {
+			TRACE_EXIT seg_sz - start;
+		}
+		TRACE_EXIT size;
+	}
+	seg_sz = ftape_read_segment_fraction(segment, buffer, read_mode,
+					     start, size);
+	TRACE(ft_t_data_flow, "segment %d, result %d", segment, seg_sz);
+	if ((int)seg_sz >= 0 && start == 0 && size == FT_SEGMENT_SIZE) {
+		/*  this implicitly assumes that we are always called with
+		 *  buffer == zft_deblock_buf 
+		 */
+		zft_deblock_segment = segment;
+	} else {
+		zft_deblock_segment = -1;
+	}
+	TRACE_EXIT seg_sz;
+}
+
+/*
+ * out:
+ *
+ * int *read_cnt: the number of bytes we removed from the
+ *                zft_deblock_buf (result)
+ *
+ * int *to_do   : the remaining size of the read-request. Is changed.
+ *
+ * in:
+ *
+ * char *buff      : buff is the address of the upper part of the user
+ *                   buffer, that hasn't been filled with data yet.
+ * int buf_pos_read: copy of buf_pos_rd
+ * int buf_len_read: copy of buf_len_rd
+ * char *zft_deblock_buf: ftape_zft_deblock_buf
+ *
+ * returns the amount of data actually copied to the user-buffer
+ *
+ * to_do MUST NOT SHRINK except to indicate an EOT. In this case to_do
+ * has to be set to 0. We cannot return -ENOSPC, because we return the
+ * amount of data actually * copied to the user-buffer
+ */
+static int zft_simple_read (int *read_cnt, 
+			    __u8  __user *dst_buf, 
+			    const int to_do, 
+			    const __u8 *src_buf, 
+			    const int seg_sz, 
+			    const zft_position *pos,
+			    const zft_volinfo *volume)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (seg_sz - pos->seg_byte_pos < to_do) {
+		*read_cnt = seg_sz - pos->seg_byte_pos;
+	} else {
+		*read_cnt = to_do;
+	}
+	if (copy_to_user(dst_buf, 
+			 src_buf + pos->seg_byte_pos, *read_cnt) != 0) {
+		TRACE_EXIT -EFAULT;
+	}
+	TRACE(ft_t_noise, "nr bytes just read: %d", *read_cnt);
+	TRACE_EXIT *read_cnt;
+}
+
+/* req_len: gets clipped due to EOT of EOF.
+ * req_clipped: is a flag indicating whether req_len was clipped or not
+ * volume: contains information on current volume (blk_sz etc.)
+ */
+static int check_read_access(int *req_len, 
+			     const zft_volinfo **volume,
+			     int *req_clipped, 
+			     const zft_position *pos)
+{
+	static __s64 remaining;
+	static int eod;
+	TRACE_FUN(ft_t_flow);
+	
+	if (zft_io_state != zft_reading) {
+		if (zft_offline) { /* offline includes no_tape */
+			TRACE_ABORT(-ENXIO, ft_t_warn,
+				    "tape is offline or no cartridge");
+		}
+		if (!ft_formatted) {
+			TRACE_ABORT(-EACCES,
+				    ft_t_warn, "tape is not formatted");
+		}
+		/*  now enter defined state, read header segment if not
+		 *  already done and flush write buffers
+		 */
+		TRACE_CATCH(zft_def_idle_state(),);
+		zft_io_state = zft_reading;
+		if (zft_tape_at_eod(pos)) {
+			eod = 1;
+			TRACE_EXIT 1;
+		}
+		eod = 0;
+		*volume = zft_find_volume(pos->seg_pos);
+		/* get the space left until EOF */
+		remaining = zft_check_for_eof(*volume, pos);
+		buf_len_rd = 0;
+		TRACE(ft_t_noise, "remaining: " LL_X ", vol_no: %d",
+		      LL(remaining), (*volume)->count);
+	} else if (zft_tape_at_eod(pos)) {
+		if (++eod > 2) {
+			TRACE_EXIT -EIO; /* st.c also returns -EIO */
+		} else {
+			TRACE_EXIT 1;
+		}
+	}
+	if ((*req_len % (*volume)->blk_sz) != 0) {
+		/*  this message is informational only. The user gets the
+		 *  proper return value
+		 */
+		TRACE_ABORT(-EINVAL, ft_t_info,
+			    "req_len %d not a multiple of block size %d",
+			    *req_len, (*volume)->blk_sz);
+	}
+	/* As GNU tar doesn't accept partial read counts when the
+	 * multiple volume flag is set, we make sure to return the
+	 * requested amount of data. Except, of course, at the end of
+	 * the tape or file mark.  
+	 */
+	remaining -= *req_len;
+	if (remaining <= 0) {
+		TRACE(ft_t_noise, 
+		      "clipped request from %d to %d.", 
+		      *req_len, (int)(*req_len + remaining));
+		*req_len += remaining;
+		*req_clipped = 1;
+	} else {
+		*req_clipped = 0;
+	}
+	TRACE_EXIT 0;
+}
+
+/* this_segs_size: the current segment's size.
+ * buff: the USER-SPACE buffer provided by the calling function.
+ * req_len: how much data should be read at most.
+ * volume: contains information on current volume (blk_sz etc.)
+ */  
+static int empty_deblock_buf(__u8 __user *usr_buf, const int req_len,
+			     const __u8 *src_buf, const int seg_sz,
+			     zft_position *pos,
+			     const zft_volinfo *volume)
+{
+	int cnt;
+	int result = 0;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_data_flow, "this_segs_size: %d", seg_sz);
+	if (zft_use_compression && volume->use_compression) {
+		TRACE_CATCH(zft_cmpr_lock(1 /* try to load */),);
+		TRACE_CATCH(result= (*zft_cmpr_ops->read)(&cnt,
+							  usr_buf, req_len,
+							  src_buf, seg_sz,
+							  pos, volume),);
+	} else {                                  
+		TRACE_CATCH(result= zft_simple_read (&cnt,
+						     usr_buf, req_len,
+						     src_buf, seg_sz,
+						     pos, volume),);
+	}
+	pos->volume_pos   += result;
+        pos->tape_pos     += cnt;
+	pos->seg_byte_pos += cnt;
+	buf_len_rd        -= cnt; /* remaining bytes in buffer */
+	TRACE(ft_t_data_flow, "buf_len_rd: %d, cnt: %d", buf_len_rd, cnt);
+	if(pos->seg_byte_pos >= seg_sz) {
+		pos->seg_pos++;
+		pos->seg_byte_pos = 0;
+	}
+	TRACE(ft_t_data_flow, "bytes moved out of deblock-buffer: %d", cnt);
+	TRACE_EXIT result;
+}
+
+
+/* note: we store the segment id of the segment that is inside the
+ * deblock buffer. This spares a lot of ftape_read_segment()s when we
+ * use small block-sizes. The block-size may be 1kb (SECTOR_SIZE). In
+ * this case a MTFSR 28 maybe still inside the same segment.
+ */
+int _zft_read(char __user *buff, int req_len)
+{
+	int req_clipped;
+	int result     = 0;
+	int bytes_read = 0;
+	static unsigned int seg_sz = 0;
+	static const zft_volinfo *volume = NULL;
+	TRACE_FUN(ft_t_flow);
+	
+	zft_resid = req_len;
+	result = check_read_access(&req_len, &volume,
+				   &req_clipped, &zft_pos);
+	switch(result) {
+	case 0: 
+		break; /* nothing special */
+	case 1: 
+		TRACE(ft_t_noise, "EOD reached");
+		TRACE_EXIT 0;   /* EOD */
+	default:
+		TRACE_ABORT(result, ft_t_noise,
+			    "check_read_access() failed with result %d",
+			    result);
+		TRACE_EXIT result;
+	}
+	while (req_len > 0) { 
+		/*  Allow escape from this loop on signal !
+		 */
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		/* buf_len_rd == 0 means that we need to read a new
+		 * segment.
+		 */
+		if (buf_len_rd == 0) {
+			while((result = zft_fetch_segment(zft_pos.seg_pos,
+							  zft_deblock_buf,
+							  FT_RD_AHEAD)) == 0) {
+				zft_pos.seg_pos ++;
+				zft_pos.seg_byte_pos = 0;
+			}
+			if (result < 0) {
+				zft_resid -= bytes_read;
+				TRACE_ABORT(result, ft_t_noise,
+					    "zft_fetch_segment(): %d",
+					    result);
+			}
+			seg_sz = result;
+			buf_len_rd = seg_sz - zft_pos.seg_byte_pos;
+		}
+		TRACE_CATCH(result = empty_deblock_buf(buff, 
+						       req_len,
+						       zft_deblock_buf, 
+						       seg_sz, 
+						       &zft_pos,
+						       volume),
+			    zft_resid -= bytes_read);
+		TRACE(ft_t_data_flow, "bytes just read: %d", result);
+		bytes_read += result; /* what we got so far       */
+		buff       += result; /* index in user-buffer     */
+		req_len    -= result; /* what's left from req_len */
+	} /* while (req_len  > 0) */
+	if (req_clipped) {
+		TRACE(ft_t_data_flow,
+		      "maybe partial count because of eof mark");
+		if (zft_just_before_eof && bytes_read == 0) {
+			/* req_len was > 0, but user didn't get
+			 * anything the user has read in the eof-mark 
+			 */
+			zft_move_past_eof(&zft_pos);
+			ftape_abort_operation();
+		} else {
+			/* don't skip to the next file before the user
+			 * tried to read a second time past EOF Just
+			 * mark that we are at EOF and maybe decrement
+			 * zft_seg_pos to stay in the same volume;
+			 */
+			zft_just_before_eof = 1;
+			zft_position_before_eof(&zft_pos, volume);
+			TRACE(ft_t_noise, "just before eof");
+		}
+	}
+	zft_resid -= result; /* for MTSTATUS       */
+	TRACE_EXIT bytes_read;
+}
diff --git a/drivers/char/ftape/zftape/zftape-read.h b/drivers/char/ftape/zftape/zftape-read.h
new file mode 100644
index 0000000..42941de
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-read.h
@@ -0,0 +1,53 @@
+#ifndef _ZFTAPE_READ_H
+#define _ZFTAPE_READ_H
+
+/*
+ * Copyright (C) 1996, 1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-read.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:19:07 $
+ *
+ *      This file contains the definitions for the read functions
+ *      for the zftape driver for Linux.
+ *
+ */
+
+#include "../lowlevel/ftape-read.h"
+
+/*      ftape-read.c defined global vars.
+ */
+extern int zft_just_before_eof;
+	
+/*      ftape-read.c defined global functions.
+ */
+extern void zft_zap_read_buffers(void);
+extern int  zft_read_header_segments(void);
+extern int  zft_fetch_segment_fraction(const unsigned int segment,
+				       void *buffer,
+				       const ft_read_mode_t read_mode,
+				       const unsigned int start,
+				       const unsigned int size);
+#define zft_fetch_segment(segment, address, read_mode)		\
+	zft_fetch_segment_fraction(segment, address, read_mode,	\
+				   0, FT_SEGMENT_SIZE)
+/*   hook for the VFS interface
+ */
+extern int  _zft_read(char __user *buff, int req_len);
+
+#endif /* _ZFTAPE_READ_H */
diff --git a/drivers/char/ftape/zftape/zftape-rw.c b/drivers/char/ftape/zftape/zftape-rw.c
new file mode 100644
index 0000000..a61ef50
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-rw.c
@@ -0,0 +1,376 @@
+/*
+ *      Copyright (C) 1996, 1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-rw.c,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:19:08 $
+ *
+ *      This file contains some common code for the r/w code for
+ *      zftape.
+ */
+
+#include <linux/config.h> /* for CONFIG_ZFT_DFLT_BLK_SZ */
+#include <linux/errno.h>
+#include <linux/mm.h>
+
+#include <linux/zftape.h>
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-eof.h"
+#include "../zftape/zftape-ctl.h"
+#include "../zftape/zftape-write.h"
+#include "../zftape/zftape-read.h"
+#include "../zftape/zftape-rw.h"
+#include "../zftape/zftape-vtbl.h"
+
+/*      Global vars.
+ */
+
+__u8 *zft_deblock_buf;
+__u8 *zft_hseg_buf;
+int zft_deblock_segment = -1;
+zft_status_enum zft_io_state = zft_idle;
+int zft_header_changed;
+int zft_qic113; /* conform to old specs. and old zftape */
+int zft_use_compression;
+zft_position zft_pos = {
+	-1, /* seg_pos */
+	0,  /* seg_byte_pos */
+	0,  /* tape_pos */
+	0   /* volume_pos */
+};
+unsigned int zft_blk_sz = CONFIG_ZFT_DFLT_BLK_SZ;
+__s64 zft_capacity;
+
+unsigned int zft_written_segments;
+int zft_label_changed;
+
+/*      Local vars.
+ */
+
+unsigned int zft_get_seg_sz(unsigned int segment)
+{
+	int size;
+	TRACE_FUN(ft_t_any);
+	
+	size = FT_SEGMENT_SIZE - 
+		count_ones(ftape_get_bad_sector_entry(segment))*FT_SECTOR_SIZE;
+	if (size > 0) {
+		TRACE_EXIT (unsigned)size; 
+	} else {
+		TRACE_EXIT 0;
+	}
+}
+
+/* ftape_set_flags(). Claus-Justus Heine, 1994/1995
+ */
+void zft_set_flags(unsigned minor_unit)
+{     
+	TRACE_FUN(ft_t_flow);
+	
+	zft_use_compression = zft_qic_mode = 0;
+	switch (minor_unit & ZFT_MINOR_OP_MASK) {
+	case (ZFT_Q80_MODE | ZFT_ZIP_MODE):
+	case ZFT_ZIP_MODE:
+		zft_use_compression = 1;
+	case 0:
+	case ZFT_Q80_MODE:
+		zft_qic_mode = 1;
+		if (zft_mt_compression) { /* override the default */
+			zft_use_compression = 1;
+		}
+		break;
+	case ZFT_RAW_MODE:
+		TRACE(ft_t_noise, "switching to raw mode");
+		break;
+	default:
+		TRACE(ft_t_warn, "Warning:\n"
+		      KERN_INFO "Wrong combination of minor device bits.\n"
+		      KERN_INFO "Switching to raw read-only mode.");
+		zft_write_protected = 1;
+		break;
+	}
+	TRACE_EXIT;
+}
+
+/* computes the segment and byte offset inside the segment
+ * corresponding to tape_pos.
+ *
+ * tape_pos gives the offset in bytes from the beginning of the
+ * ft_first_data_segment *seg_byte_pos is the offset in the current
+ * segment in bytes
+ *
+ * Of, if this routine was called often one should cache the last data
+ * pos it was called with, but actually this is only needed in
+ * ftape_seek_block(), that is, almost never.
+ */
+int zft_calc_seg_byte_coord(int *seg_byte_pos, __s64 tape_pos)
+{
+	int segment;
+	int seg_sz;
+	TRACE_FUN(ft_t_flow);
+	
+	if (tape_pos == 0) {
+		*seg_byte_pos = 0;
+		segment = ft_first_data_segment;
+	} else {
+		seg_sz = 0;
+		
+		for (segment = ft_first_data_segment; 
+		     ((tape_pos > 0) && (segment <= ft_last_data_segment));
+		     segment++) {
+			seg_sz = zft_get_seg_sz(segment); 
+			tape_pos -= seg_sz;
+		}
+		if(tape_pos >= 0) {
+			/* the case tape_pos > != 0 means that the
+			 * argument tape_pos lies beyond the EOT.
+			 */
+			*seg_byte_pos= 0;
+		} else { /* tape_pos < 0 */
+			segment--;
+			*seg_byte_pos= tape_pos + seg_sz;
+		}
+	}
+	TRACE_EXIT(segment);
+}
+
+/* ftape_calc_tape_pos().
+ *
+ * computes the offset in bytes from the beginning of the
+ * ft_first_data_segment inverse to ftape_calc_seg_byte_coord
+ *
+ * We should do some caching. But how:
+ *
+ * Each time the header segments are read in, this routine is called
+ * with ft_tracks_per_tape*segments_per_track argumnet. So this should be
+ * the time to reset the cache.
+ *
+ * Also, it might be in the future that the bad sector map gets
+ * changed.  -> reset the cache
+ */
+static int seg_pos;
+static __s64 tape_pos;
+
+__s64 zft_get_capacity(void)
+{
+	seg_pos  = ft_first_data_segment;
+	tape_pos = 0;
+
+	while (seg_pos <= ft_last_data_segment) {
+		tape_pos += zft_get_seg_sz(seg_pos ++);
+	}
+	return tape_pos;
+}
+
+__s64 zft_calc_tape_pos(int segment)
+{
+	int d1, d2, d3;
+	TRACE_FUN(ft_t_any);
+	
+	if (segment > ft_last_data_segment) {
+	        TRACE_EXIT zft_capacity;
+	}
+	if (segment < ft_first_data_segment) {
+		TRACE_EXIT 0;
+	}
+	d2 = segment - seg_pos;
+	if (-d2 > 10) {
+		d1 = segment - ft_first_data_segment;
+		if (-d2 > d1) {
+			tape_pos = 0;
+			seg_pos = ft_first_data_segment;
+			d2 = d1;
+		}
+	}
+	if (d2 > 10) {
+		d3 = ft_last_data_segment - segment;
+		if (d2 > d3) {
+			tape_pos = zft_capacity;
+			seg_pos  = ft_last_data_segment + 1;
+			d2 = -d3;
+		}
+	}		
+	if (d2 > 0) {
+		while (seg_pos < segment) {
+			tape_pos +=  zft_get_seg_sz(seg_pos++);
+		}
+	} else {
+		while (seg_pos > segment) {
+			tape_pos -=  zft_get_seg_sz(--seg_pos);
+		}
+	}
+	TRACE(ft_t_noise, "new cached pos: %d", seg_pos);
+
+	TRACE_EXIT tape_pos;
+}
+
+/* copy Z-label string to buffer, keeps track of the correct offset in
+ * `buffer' 
+ */
+void zft_update_label(__u8 *buffer)
+{ 
+	TRACE_FUN(ft_t_flow);
+	
+	if (strncmp(&buffer[FT_LABEL], ZFTAPE_LABEL, 
+		    sizeof(ZFTAPE_LABEL)-1) != 0) {
+		TRACE(ft_t_info, "updating label from \"%s\" to \"%s\"",
+		      &buffer[FT_LABEL], ZFTAPE_LABEL);
+		strcpy(&buffer[FT_LABEL], ZFTAPE_LABEL);
+		memset(&buffer[FT_LABEL] + sizeof(ZFTAPE_LABEL) - 1, ' ', 
+		       FT_LABEL_SZ - sizeof(ZFTAPE_LABEL + 1));
+		PUT4(buffer, FT_LABEL_DATE, 0);
+		zft_label_changed = zft_header_changed = 1; /* changed */
+	}
+	TRACE_EXIT;
+}
+
+int zft_verify_write_segments(unsigned int segment, 
+			      __u8 *data, size_t size,
+			      __u8 *buffer)
+{
+	int result;
+	__u8 *write_buf;
+	__u8 *src_buf;
+	int single;
+	int seg_pos;
+	int seg_sz;
+	int remaining;
+	ft_write_mode_t write_mode;
+	TRACE_FUN(ft_t_flow);
+
+	seg_pos   = segment;
+	seg_sz    = zft_get_seg_sz(seg_pos);
+	src_buf   = data;
+	single    = size <= seg_sz;
+	remaining = size;
+	do {
+		TRACE(ft_t_noise, "\n"
+		      KERN_INFO "remaining: %d\n"
+		      KERN_INFO "seg_sz   : %d\n"
+		      KERN_INFO "segment  : %d",
+		      remaining, seg_sz, seg_pos);
+		if (remaining == seg_sz) {
+			write_buf = src_buf;
+			write_mode = single ? FT_WR_SINGLE : FT_WR_MULTI;
+			remaining = 0;
+		} else if (remaining > seg_sz) {
+			write_buf = src_buf;
+			write_mode = FT_WR_ASYNC; /* don't start tape */
+			remaining -= seg_sz;
+		} else { /* remaining < seg_sz */
+			write_buf = buffer;
+			memcpy(write_buf, src_buf, remaining);
+			memset(&write_buf[remaining],'\0',seg_sz-remaining);
+			write_mode = single ? FT_WR_SINGLE : FT_WR_MULTI;
+			remaining = 0;
+		}
+		if ((result = ftape_write_segment(seg_pos, 
+						  write_buf, 
+						  write_mode)) != seg_sz) {
+			TRACE(ft_t_err, "Error: "
+			      "Couldn't write segment %d", seg_pos);
+			TRACE_EXIT result < 0 ? result : -EIO; /* bail out */
+		}
+		zft_written_segments ++;
+		seg_sz = zft_get_seg_sz(++seg_pos);
+		src_buf += result;
+	} while (remaining > 0);
+	if (ftape_get_status()->fti_state == writing) {
+		TRACE_CATCH(ftape_loop_until_writes_done(),);
+		TRACE_CATCH(ftape_abort_operation(),);
+		zft_prevent_flush();
+	}
+	seg_pos = segment;
+	src_buf = data;
+	remaining = size;
+	do {
+		TRACE_CATCH(result = ftape_read_segment(seg_pos, buffer, 
+							single ? FT_RD_SINGLE
+							: FT_RD_AHEAD),);
+		if (memcmp(src_buf, buffer, 
+			   remaining > result ? result : remaining) != 0) {
+			TRACE_ABORT(-EIO, ft_t_err,
+				    "Failed to verify written segment %d",
+				    seg_pos);
+		}
+		remaining -= result;
+		TRACE(ft_t_noise, "verify successful:\n"
+		      KERN_INFO "segment  : %d\n"
+		      KERN_INFO "segsize  : %d\n"
+		      KERN_INFO "remaining: %d",
+		      seg_pos, result, remaining);
+		src_buf   += seg_sz;
+		seg_pos++;
+	} while (remaining > 0);
+	TRACE_EXIT size;
+}
+
+
+/* zft_erase().  implemented compression-handling
+ *
+ * calculate the first data-segment when using/not using compression.
+ *
+ * update header-segment and compression-map-segment.
+ */
+int zft_erase(void)
+{
+	int result = 0;
+	TRACE_FUN(ft_t_flow);
+	
+	if (!zft_header_read) {
+		TRACE_CATCH(zft_vmalloc_once((void **)&zft_hseg_buf,
+					     FT_SEGMENT_SIZE),);
+		/* no need to read the vtbl and compression map */
+		TRACE_CATCH(ftape_read_header_segment(zft_hseg_buf),);
+		if ((zft_old_ftape = 
+		     zft_ftape_validate_label(&zft_hseg_buf[FT_LABEL]))) {
+			zft_ftape_extract_file_marks(zft_hseg_buf);
+		}
+		TRACE(ft_t_noise,
+		      "ft_first_data_segment: %d, ft_last_data_segment: %d", 
+		      ft_first_data_segment, ft_last_data_segment);
+		zft_qic113 = (ft_format_code != fmt_normal &&
+			      ft_format_code != fmt_1100ft &&
+			      ft_format_code != fmt_425ft);
+	}
+	if (zft_old_ftape) {
+		zft_clear_ftape_file_marks();
+		zft_old_ftape = 0; /* no longer old ftape */
+	}
+	PUT2(zft_hseg_buf, FT_CMAP_START, 0);
+	zft_volume_table_changed = 1;
+	zft_capacity = zft_get_capacity();
+	zft_init_vtbl();
+	/* the rest must be done in ftape_update_header_segments 
+	 */
+	zft_header_read = 1;
+	zft_header_changed = 1; /* force update of timestamp */
+	result = zft_update_header_segments();
+
+	ftape_abort_operation();
+
+	zft_reset_position(&zft_pos);
+	zft_set_flags (zft_unit);
+	TRACE_EXIT result;
+}
+
+unsigned int zft_get_time(void) 
+{
+	unsigned int date = FT_TIME_STAMP(2097, 11, 30, 23, 59, 59); /* fun */
+	return date;
+}
diff --git a/drivers/char/ftape/zftape/zftape-rw.h b/drivers/char/ftape/zftape/zftape-rw.h
new file mode 100644
index 0000000..14c07f0
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-rw.h
@@ -0,0 +1,102 @@
+#ifndef _ZFTAPE_RW_H
+#define _ZFTAPE_RW_H
+
+/*
+ * Copyright (C) 1996, 1997 Claus-Justus Heine.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-rw.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:19:09 $
+ *
+ *      This file contains the definitions for the read and write
+ *      functions for the QIC-117 floppy-tape driver for Linux.
+ *
+ */
+
+#include <linux/config.h> /* for CONFIG_ZFT_DFLT_BLK_SZ */
+#include "../zftape/zftape-buffers.h"
+
+#define SEGMENTS_PER_TAPE  (ft_segments_per_track * ft_tracks_per_tape)
+
+/*  QIC-113 Rev. G says that `a maximum of 63488 raw bytes may be
+ *  compressed into a single frame'.
+ *  Maybe we should stick to 32kb to make it more `beautiful'
+ */
+#define ZFT_MAX_BLK_SZ           (62*1024) /* bytes */
+#if !defined(CONFIG_ZFT_DFLT_BLK_SZ)
+# define CONFIG_ZFT_DFLT_BLK_SZ   (10*1024) /* bytes, default of gnu tar */
+#elif CONFIG_ZFT_DFLT_BLK_SZ == 0
+# undef  CONFIG_ZFT_DFLT_BLK_SZ
+# define CONFIG_ZFT_DFLT_BLK_SZ 1
+#elif (CONFIG_ZFT_DFLT_BLK_SZ % 1024) != 0
+# error CONFIG_ZFT_DFLT_BLK_SZ must be 1 or a multiple of 1024
+#endif
+/* The *optional* compression routines need some overhead per tape
+ *  block for their purposes. Instead of asking the actual compression
+ *  implementation how much it needs, we restrict this overhead to be
+ *  maximal of ZFT_CMPT_OVERHEAD size. We need this for EOT
+ *  conditions. The tape is assumed to be logical at EOT when the
+ *  distance from the physical EOT is less than 
+ *  one tape block + ZFT_CMPR_OVERHEAD 
+ */
+#define ZFT_CMPR_OVERHEAD 16        /* bytes */
+
+typedef enum
+{ 
+	zft_idle = 0,
+	zft_reading,
+	zft_writing,
+} zft_status_enum;
+
+typedef struct               /*  all values measured in bytes */
+{
+	int   seg_pos;       /*  segment currently positioned at */
+	int   seg_byte_pos;  /*  offset in current segment */ 
+	__s64 tape_pos;      /*  real offset from BOT */
+	__s64 volume_pos;    /*  pos. in uncompressed data stream in
+			      *  current volume 
+			      */
+} zft_position; 
+
+extern zft_position zft_pos;
+extern __u8 *zft_deblock_buf;
+extern __u8 *zft_hseg_buf;
+extern int zft_deblock_segment;
+extern zft_status_enum zft_io_state;
+extern int zft_header_changed;
+extern int zft_qic113; /* conform to old specs. and old zftape */
+extern int zft_use_compression;
+extern unsigned int zft_blk_sz;
+extern __s64 zft_capacity;
+extern unsigned int zft_written_segments;
+extern int zft_label_changed;
+
+/*  zftape-rw.c exported functions
+ */
+extern unsigned int zft_get_seg_sz(unsigned int segment);
+extern void  zft_set_flags(unsigned int minor_unit);
+extern int   zft_calc_seg_byte_coord(int *seg_byte_pos, __s64 tape_pos);
+extern __s64 zft_calc_tape_pos(int segment);
+extern __s64 zft_get_capacity(void);
+extern void  zft_update_label(__u8 *buffer);
+extern int   zft_erase(void);
+extern int   zft_verify_write_segments(unsigned int segment, 
+				       __u8 *data, size_t size, __u8 *buffer);
+extern unsigned int zft_get_time(void);
+#endif /* _ZFTAPE_RW_H */
+
diff --git a/drivers/char/ftape/zftape/zftape-vtbl.c b/drivers/char/ftape/zftape/zftape-vtbl.c
new file mode 100644
index 0000000..ad7f8be
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-vtbl.c
@@ -0,0 +1,757 @@
+/*
+ *      Copyright (c) 1995-1997 Claus-Justus Heine 
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2, or (at
+ your option) any later version.
+ 
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+ 
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-vtbl.c,v $
+ * $Revision: 1.7.6.1 $
+ * $Date: 1997/11/24 13:48:31 $
+ *
+ *      This file defines a volume table as defined in various QIC
+ *      standards.
+ * 
+ *      This is a minimal implementation, just allowing ordinary DOS
+ *      :( prgrams to identify the cartridge as used.
+ */
+
+#include <linux/errno.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+
+#include <linux/zftape.h>
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-eof.h"
+#include "../zftape/zftape-ctl.h"
+#include "../zftape/zftape-write.h"
+#include "../zftape/zftape-read.h"
+#include "../zftape/zftape-rw.h"
+#include "../zftape/zftape-vtbl.h"
+
+#define ZFT_CMAP_HACK /* leave this defined to hide the compression map */
+
+/*
+ *  global variables 
+ */
+int zft_qic_mode   = 1; /* use the vtbl */
+int zft_old_ftape; /* prevents old ftaped tapes to be overwritten */
+int zft_volume_table_changed; /* for write_header_segments() */
+
+/*
+ *  private variables (only exported for inline functions)
+ */
+LIST_HEAD(zft_vtbl);
+
+/*  We could also allocate these dynamically when extracting the volume table
+ *  sizeof(zft_volinfo) is about 32 or something close to that
+ */
+static zft_volinfo  tape_vtbl;
+static zft_volinfo  eot_vtbl;
+static zft_volinfo *cur_vtbl;
+
+static inline void zft_new_vtbl_entry(void)
+{
+	struct list_head *tmp = &zft_last_vtbl->node;
+	zft_volinfo *new = zft_kmalloc(sizeof(zft_volinfo));
+
+	list_add(&new->node, tmp);
+	new->count = zft_eom_vtbl->count ++;
+}
+
+void zft_free_vtbl(void)
+{
+	for (;;) {
+		struct list_head *tmp = zft_vtbl.prev;
+		zft_volinfo *vtbl;
+
+		if (tmp == &zft_vtbl)
+			break;
+		list_del(tmp);
+		vtbl = list_entry(tmp, zft_volinfo, node);
+		zft_kfree(vtbl, sizeof(zft_volinfo));
+	}
+	INIT_LIST_HEAD(&zft_vtbl);
+	cur_vtbl = NULL;
+}
+
+/*  initialize vtbl, called by ftape_new_cartridge()
+ */
+void zft_init_vtbl(void)
+{ 
+	zft_volinfo *new;
+
+	zft_free_vtbl();
+	
+	/*  Create the two dummy vtbl entries
+	 */
+	new = zft_kmalloc(sizeof(zft_volinfo));
+	list_add(&new->node, &zft_vtbl);
+	new = zft_kmalloc(sizeof(zft_volinfo));
+	list_add(&new->node, &zft_vtbl);
+	zft_head_vtbl->end_seg   = ft_first_data_segment;
+	zft_head_vtbl->blk_sz    = zft_blk_sz;
+	zft_head_vtbl->count     = -1;
+	zft_eom_vtbl->start_seg  = ft_first_data_segment + 1;
+	zft_eom_vtbl->end_seg    = ft_last_data_segment + 1;
+	zft_eom_vtbl->blk_sz     = zft_blk_sz;
+	zft_eom_vtbl->count      = 0;
+
+	/*  Reset the pointer for zft_find_volume()
+	 */
+	cur_vtbl = zft_eom_vtbl;
+
+	/* initialize the dummy vtbl entries for zft_qic_mode == 0
+	 */
+	eot_vtbl.start_seg       = ft_last_data_segment + 1;
+	eot_vtbl.end_seg         = ft_last_data_segment + 1;
+	eot_vtbl.blk_sz          = zft_blk_sz;
+	eot_vtbl.count           = -1;
+	tape_vtbl.start_seg = ft_first_data_segment;
+	tape_vtbl.end_seg   = ft_last_data_segment;
+	tape_vtbl.blk_sz    = zft_blk_sz;
+	tape_vtbl.size      = zft_capacity;
+	tape_vtbl.count     = 0;
+}
+
+/* check for a valid VTBL signature. 
+ */
+static int vtbl_signature_valid(__u8 signature[4])
+{
+	const char *vtbl_ids[] = VTBL_IDS; /* valid signatures */
+	int j;
+	
+	for (j = 0; 
+	     (j < NR_ITEMS(vtbl_ids)) && (memcmp(signature, vtbl_ids[j], 4) != 0);
+	     j++);
+	return j < NR_ITEMS(vtbl_ids);
+}
+
+/* We used to store the block-size of the volume in the volume-label,
+ * using the keyword "blocksize". The blocksize written to the
+ * volume-label is in bytes.
+ *
+ * We use this now only for compatibility with old zftape version. We
+ * store the blocksize directly as binary number in the vendor
+ * extension part of the volume entry.
+ */
+static int check_volume_label(const char *label, int *blk_sz)
+{ 
+	int valid_format;
+	char *blocksize;
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE(ft_t_noise, "called with \"%s\" / \"%s\"", label, ZFT_VOL_NAME);
+	if (strncmp(label, ZFT_VOL_NAME, strlen(ZFT_VOL_NAME)) != 0) {
+		*blk_sz = 1; /* smallest block size that we allow */
+		valid_format = 0;
+	} else {
+		TRACE(ft_t_noise, "got old style zftape vtbl entry");
+		/* get the default blocksize */
+		/* use the kernel strstr()   */
+		blocksize= strstr(label, " blocksize ");
+		if (blocksize) {
+			blocksize += strlen(" blocksize ");
+			for(*blk_sz= 0; 
+			    *blocksize >= '0' && *blocksize <= '9'; 
+			    blocksize++) {
+				*blk_sz *= 10;
+				*blk_sz += *blocksize - '0';
+			}
+			if (*blk_sz > ZFT_MAX_BLK_SZ) {
+				*blk_sz= 1;
+				valid_format= 0;
+			} else {
+				valid_format = 1;
+			}
+		} else {
+			*blk_sz= 1;
+			valid_format= 0;
+		}
+	}
+	TRACE_EXIT valid_format;
+}
+
+/*   check for a zftape volume
+ */
+static int check_volume(__u8 *entry, zft_volinfo *volume)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	if(strncmp(&entry[VTBL_EXT+EXT_ZFTAPE_SIG], ZFTAPE_SIG,
+		   strlen(ZFTAPE_SIG)) == 0) {
+		TRACE(ft_t_noise, "got new style zftape vtbl entry");
+		volume->blk_sz = GET2(entry, VTBL_EXT+EXT_ZFTAPE_BLKSZ);
+		volume->qic113 = entry[VTBL_EXT+EXT_ZFTAPE_QIC113];
+		TRACE_EXIT 1;
+	} else {
+		TRACE_EXIT check_volume_label(&entry[VTBL_DESC], &volume->blk_sz);
+	}
+}
+
+
+/* create zftape specific vtbl entry, the volume bounds are inserted
+ * in the calling function, zft_create_volume_headers()
+ */
+static void create_zft_volume(__u8 *entry, zft_volinfo *vtbl)
+{
+	TRACE_FUN(ft_t_flow);
+
+	memset(entry, 0, VTBL_SIZE);
+	memcpy(&entry[VTBL_SIG], VTBL_ID, 4);
+	sprintf(&entry[VTBL_DESC], ZFT_VOL_NAME" %03d", vtbl->count);
+	entry[VTBL_FLAGS] = (VTBL_FL_NOT_VERIFIED | VTBL_FL_SEG_SPANNING);
+	entry[VTBL_M_NO] = 1; /* multi_cartridge_count */
+	strcpy(&entry[VTBL_EXT+EXT_ZFTAPE_SIG], ZFTAPE_SIG);
+	PUT2(entry, VTBL_EXT+EXT_ZFTAPE_BLKSZ, vtbl->blk_sz);
+	if (zft_qic113) {
+		PUT8(entry, VTBL_DATA_SIZE, vtbl->size);
+		entry[VTBL_CMPR] = VTBL_CMPR_UNREG; 
+		if (vtbl->use_compression) { /* use compression: */
+			entry[VTBL_CMPR] |= VTBL_CMPR_USED;
+		}
+		entry[VTBL_EXT+EXT_ZFTAPE_QIC113] = 1;
+	} else {
+		PUT4(entry, VTBL_DATA_SIZE, vtbl->size);
+		entry[VTBL_K_CMPR] = VTBL_CMPR_UNREG; 
+		if (vtbl->use_compression) { /* use compression: */
+			entry[VTBL_K_CMPR] |= VTBL_CMPR_USED;
+		}
+	}
+	if (ft_format_code == fmt_big) {
+		/* SCSI like vtbl, store the number of used
+		 * segments as 4 byte value 
+		 */
+		PUT4(entry, VTBL_SCSI_SEGS, vtbl->end_seg-vtbl->start_seg + 1);
+	} else {
+		/* normal, QIC-80MC like vtbl 
+		 */
+		PUT2(entry, VTBL_START, vtbl->start_seg);
+		PUT2(entry, VTBL_END, vtbl->end_seg);
+	}
+	TRACE_EXIT;
+}
+
+/* this one creates the volume headers for each volume. It is assumed
+ * that buffer already contains the old volume-table, so that vtbl
+ * entries without the zft_volume flag set can savely be ignored.
+ */
+static void zft_create_volume_headers(__u8 *buffer)
+{   
+	__u8 *entry;
+	struct list_head *tmp;
+	zft_volinfo *vtbl;
+	TRACE_FUN(ft_t_flow);
+	
+#ifdef ZFT_CMAP_HACK
+	if((strncmp(&buffer[VTBL_EXT+EXT_ZFTAPE_SIG], ZFTAPE_SIG,
+		    strlen(ZFTAPE_SIG)) == 0) && 
+	   buffer[VTBL_EXT+EXT_ZFTAPE_CMAP] != 0) {
+		TRACE(ft_t_noise, "deleting cmap volume");
+		memmove(buffer, buffer + VTBL_SIZE,
+			FT_SEGMENT_SIZE - VTBL_SIZE);
+	}
+#endif
+	entry = buffer;
+	for (tmp = zft_head_vtbl->node.next;
+	     tmp != &zft_eom_vtbl->node;
+	     tmp = tmp->next) {
+		vtbl = list_entry(tmp, zft_volinfo, node);
+		/* we now fill in the values only for newly created volumes.
+		 */
+		if (vtbl->new_volume) {
+			create_zft_volume(entry, vtbl);
+			vtbl->new_volume = 0; /* clear the flag */
+		}
+		
+		DUMP_VOLINFO(ft_t_noise, &entry[VTBL_DESC], vtbl);
+		entry += VTBL_SIZE;
+	}
+	memset(entry, 0, FT_SEGMENT_SIZE - zft_eom_vtbl->count * VTBL_SIZE);
+	TRACE_EXIT;
+}
+
+/*  write volume table to tape. Calls zft_create_volume_headers()
+ */
+int zft_update_volume_table(unsigned int segment)
+{
+	int result = 0;
+	__u8 *verify_buf = NULL;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE_CATCH(result = ftape_read_segment(ft_first_data_segment, 
+						zft_deblock_buf,
+						FT_RD_SINGLE),);
+	zft_create_volume_headers(zft_deblock_buf);
+	TRACE(ft_t_noise, "writing volume table segment %d", segment);
+	if (zft_vmalloc_once(&verify_buf, FT_SEGMENT_SIZE) == 0) {
+		TRACE_CATCH(zft_verify_write_segments(segment, 
+						      zft_deblock_buf, result,
+						      verify_buf),
+			    zft_vfree(&verify_buf, FT_SEGMENT_SIZE));
+		zft_vfree(&verify_buf, FT_SEGMENT_SIZE);
+	} else {
+		TRACE_CATCH(ftape_write_segment(segment, zft_deblock_buf, 
+						FT_WR_SINGLE),);
+	}
+	TRACE_EXIT 0;
+}
+
+/* non zftape volumes are handled in raw mode. Thus we need to
+ * calculate the raw amount of data contained in those segments.  
+ */
+static void extract_alien_volume(__u8 *entry, zft_volinfo *vtbl)
+{
+	TRACE_FUN(ft_t_flow);
+
+	vtbl->size  = (zft_calc_tape_pos(zft_last_vtbl->end_seg+1) -
+		       zft_calc_tape_pos(zft_last_vtbl->start_seg));
+	vtbl->use_compression = 0;
+	vtbl->qic113 = zft_qic113;
+	if (vtbl->qic113) {
+		TRACE(ft_t_noise, 
+		      "Fake alien volume's size from " LL_X " to " LL_X, 
+		      LL(GET8(entry, VTBL_DATA_SIZE)), LL(vtbl->size));
+	} else {
+		TRACE(ft_t_noise,
+		      "Fake alien volume's size from %d to " LL_X, 
+		      (int)GET4(entry, VTBL_DATA_SIZE), LL(vtbl->size));
+	}
+	TRACE_EXIT;
+}
+
+
+/* extract an zftape specific volume
+ */
+static void extract_zft_volume(__u8 *entry, zft_volinfo *vtbl)
+{
+	TRACE_FUN(ft_t_flow);
+
+	if (vtbl->qic113) {
+		vtbl->size = GET8(entry, VTBL_DATA_SIZE);
+		vtbl->use_compression = 
+			(entry[VTBL_CMPR] & VTBL_CMPR_USED) != 0; 
+	} else {
+		vtbl->size = GET4(entry, VTBL_DATA_SIZE);
+		if (entry[VTBL_K_CMPR] & VTBL_CMPR_UNREG) {
+			vtbl->use_compression = 
+				(entry[VTBL_K_CMPR] & VTBL_CMPR_USED) != 0;
+		} else if (entry[VTBL_CMPR] & VTBL_CMPR_UNREG) {
+			vtbl->use_compression = 
+				(entry[VTBL_CMPR] & VTBL_CMPR_USED) != 0; 
+		} else {
+			TRACE(ft_t_warn, "Geeh! There is something wrong:\n"
+			      KERN_INFO "QIC compression (Rev = K): %x\n"
+			      KERN_INFO "QIC compression (Rev > K): %x",
+			      entry[VTBL_K_CMPR], entry[VTBL_CMPR]);
+		}
+	}
+	TRACE_EXIT;
+}
+
+/* extract the volume table from buffer. "buffer" must already contain
+ * the vtbl-segment 
+ */
+int zft_extract_volume_headers(__u8 *buffer)
+{                            
+        __u8 *entry;
+	TRACE_FUN(ft_t_flow);
+	
+	zft_init_vtbl();
+	entry = buffer;
+#ifdef ZFT_CMAP_HACK
+	if ((strncmp(&entry[VTBL_EXT+EXT_ZFTAPE_SIG], ZFTAPE_SIG,
+		     strlen(ZFTAPE_SIG)) == 0) &&
+	    entry[VTBL_EXT+EXT_ZFTAPE_CMAP] != 0) {
+		TRACE(ft_t_noise, "ignoring cmap volume");
+		entry += VTBL_SIZE;
+	} 
+#endif
+	/* the end of the vtbl is indicated by an invalid signature 
+	 */
+	while (vtbl_signature_valid(&entry[VTBL_SIG]) &&
+	       (entry - buffer) < FT_SEGMENT_SIZE) {
+		zft_new_vtbl_entry();
+		if (ft_format_code == fmt_big) {
+			/* SCSI like vtbl, stores only the number of
+			 * segments used 
+			 */
+			unsigned int num_segments= GET4(entry, VTBL_SCSI_SEGS);
+			zft_last_vtbl->start_seg = zft_eom_vtbl->start_seg;
+			zft_last_vtbl->end_seg = 
+				zft_last_vtbl->start_seg + num_segments - 1;
+		} else {
+			/* `normal', QIC-80 like vtbl 
+			 */
+			zft_last_vtbl->start_seg = GET2(entry, VTBL_START);
+			zft_last_vtbl->end_seg   = GET2(entry, VTBL_END);
+		}
+		zft_eom_vtbl->start_seg  = zft_last_vtbl->end_seg + 1;
+		/* check if we created this volume and get the
+		 * blk_sz 
+		 */
+		zft_last_vtbl->zft_volume = check_volume(entry, zft_last_vtbl);
+		if (zft_last_vtbl->zft_volume == 0) {
+			extract_alien_volume(entry, zft_last_vtbl);
+		} else {
+			extract_zft_volume(entry, zft_last_vtbl);
+		}
+		DUMP_VOLINFO(ft_t_noise, &entry[VTBL_DESC], zft_last_vtbl);
+		entry +=VTBL_SIZE;
+	}
+#if 0
+/*
+ *  undefine to test end of tape handling
+ */
+	zft_new_vtbl_entry();
+	zft_last_vtbl->start_seg = zft_eom_vtbl->start_seg;
+	zft_last_vtbl->end_seg   = ft_last_data_segment - 10;
+	zft_last_vtbl->blk_sz          = zft_blk_sz;
+	zft_last_vtbl->zft_volume      = 1;
+	zft_last_vtbl->qic113          = zft_qic113;
+	zft_last_vtbl->size = (zft_calc_tape_pos(zft_last_vtbl->end_seg+1)
+			       - zft_calc_tape_pos(zft_last_vtbl->start_seg));
+#endif
+	TRACE_EXIT 0;
+}
+
+/* this functions translates the failed_sector_log, misused as
+ * EOF-marker list, into a virtual volume table. The table mustn't be
+ * written to tape, because this would occupy the first data segment,
+ * which should be the volume table, but is actually the first segment
+ * that is filled with data (when using standard ftape).  We assume,
+ * that we get a non-empty failed_sector_log.
+ */
+int zft_fake_volume_headers (eof_mark_union *eof_map, int num_failed_sectors)
+{
+	unsigned int segment, sector;
+	int have_eom = 0;
+	int vol_no;
+	TRACE_FUN(ft_t_flow);
+
+	if ((num_failed_sectors >= 2) &&
+	    (GET2(&eof_map[num_failed_sectors - 1].mark.segment, 0) 
+	     == 
+	     GET2(&eof_map[num_failed_sectors - 2].mark.segment, 0) + 1) &&
+	    (GET2(&eof_map[num_failed_sectors - 1].mark.date, 0) == 1)) {
+		/* this should be eom. We keep the remainder of the
+		 * tape as another volume.
+		 */
+		have_eom = 1;
+	}
+	zft_init_vtbl();
+	zft_eom_vtbl->start_seg = ft_first_data_segment;
+	for(vol_no = 0; vol_no < num_failed_sectors - have_eom; vol_no ++) {
+		zft_new_vtbl_entry();
+
+		segment = GET2(&eof_map[vol_no].mark.segment, 0);
+		sector  = GET2(&eof_map[vol_no].mark.date, 0);
+
+		zft_last_vtbl->start_seg  = zft_eom_vtbl->start_seg;
+		zft_last_vtbl->end_seg    = segment;
+		zft_eom_vtbl->start_seg  = segment + 1;
+		zft_last_vtbl->blk_sz     = 1;
+		zft_last_vtbl->size       = 
+			(zft_calc_tape_pos(zft_last_vtbl->end_seg)
+			 - zft_calc_tape_pos(zft_last_vtbl->start_seg)
+			 + (sector-1) * FT_SECTOR_SIZE);
+		TRACE(ft_t_noise, 
+		      "failed sector log: segment: %d, sector: %d", 
+		      segment, sector);
+		DUMP_VOLINFO(ft_t_noise, "Faked volume", zft_last_vtbl);
+	}
+	if (!have_eom) {
+		zft_new_vtbl_entry();
+		zft_last_vtbl->start_seg = zft_eom_vtbl->start_seg;
+		zft_last_vtbl->end_seg   = ft_last_data_segment;
+		zft_eom_vtbl->start_seg  = ft_last_data_segment + 1;
+		zft_last_vtbl->size      = zft_capacity;
+		zft_last_vtbl->size     -= zft_calc_tape_pos(zft_last_vtbl->start_seg);
+		zft_last_vtbl->blk_sz    = 1;
+		DUMP_VOLINFO(ft_t_noise, "Faked volume",zft_last_vtbl);
+	}
+	TRACE_EXIT 0;
+}
+
+/* update the internal volume table
+ *
+ * if before start of last volume: erase all following volumes if
+ * inside a volume: set end of volume to infinity
+ *
+ * this function is intended to be called every time _ftape_write() is
+ * called
+ *
+ * return: 0 if no new volume was created, 1 if a new volume was
+ * created
+ *
+ * NOTE: we don't need to check for zft_mode as ftape_write() does
+ * that already. This function gets never called without accessing
+ * zftape via the *qft* devices 
+ */
+
+int zft_open_volume(zft_position *pos, int blk_sz, int use_compression)
+{ 
+	TRACE_FUN(ft_t_flow);
+	
+	if (!zft_qic_mode) {
+		TRACE_EXIT 0;
+	}
+	if (zft_tape_at_lbot(pos)) {
+		zft_init_vtbl();
+		if(zft_old_ftape) {
+			/* clear old ftape's eof marks */
+			zft_clear_ftape_file_marks();
+			zft_old_ftape = 0; /* no longer old ftape */
+		}
+		zft_reset_position(pos);
+	}
+	if (pos->seg_pos != zft_last_vtbl->end_seg + 1) {
+		TRACE_ABORT(-EIO, ft_t_bug, 
+		      "BUG: seg_pos: %d, zft_last_vtbl->end_seg: %d", 
+		      pos->seg_pos, zft_last_vtbl->end_seg);
+	}                            
+	TRACE(ft_t_noise, "create new volume");
+	if (zft_eom_vtbl->count >= ZFT_MAX_VOLUMES) {
+		TRACE_ABORT(-ENOSPC, ft_t_err,
+			    "Error: maxmimal number of volumes exhausted "
+			    "(maxmimum is %d)", ZFT_MAX_VOLUMES);
+	}
+	zft_new_vtbl_entry();
+	pos->volume_pos = pos->seg_byte_pos = 0;
+	zft_last_vtbl->start_seg       = pos->seg_pos;
+	zft_last_vtbl->end_seg         = ft_last_data_segment; /* infinity */
+	zft_last_vtbl->blk_sz          = blk_sz;
+	zft_last_vtbl->size            = zft_capacity;
+	zft_last_vtbl->zft_volume      = 1;
+	zft_last_vtbl->use_compression = use_compression;
+	zft_last_vtbl->qic113          = zft_qic113;
+	zft_last_vtbl->new_volume      = 1;
+	zft_last_vtbl->open            = 1;
+	zft_volume_table_changed = 1;
+	zft_eom_vtbl->start_seg  = ft_last_data_segment + 1;
+	TRACE_EXIT 0;
+}
+
+/*  perform mtfsf, mtbsf, not allowed without zft_qic_mode
+ */
+int zft_skip_volumes(int count, zft_position *pos)
+{ 
+	const zft_volinfo *vtbl;
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE(ft_t_noise, "count: %d", count);
+	
+	vtbl= zft_find_volume(pos->seg_pos);
+	while (count > 0 && vtbl != zft_eom_vtbl) {
+		vtbl = list_entry(vtbl->node.next, zft_volinfo, node);
+		count --;
+	}
+	while (count < 0 && vtbl != zft_first_vtbl) {
+		vtbl = list_entry(vtbl->node.prev, zft_volinfo, node);
+		count ++;
+	}
+	pos->seg_pos        = vtbl->start_seg;
+	pos->seg_byte_pos   = 0;
+	pos->volume_pos     = 0;
+	pos->tape_pos       = zft_calc_tape_pos(pos->seg_pos);
+	zft_just_before_eof = vtbl->size == 0;
+	if (zft_cmpr_ops) {
+		(*zft_cmpr_ops->reset)();
+	}
+	zft_deblock_segment = -1; /* no need to keep cache */
+	TRACE(ft_t_noise, "repositioning to:\n"
+	      KERN_INFO "zft_seg_pos        : %d\n"
+	      KERN_INFO "zft_seg_byte_pos   : %d\n"
+	      KERN_INFO "zft_tape_pos       : " LL_X "\n"
+	      KERN_INFO "zft_volume_pos     : " LL_X "\n"
+	      KERN_INFO "file number        : %d",
+	      pos->seg_pos, pos->seg_byte_pos, 
+	      LL(pos->tape_pos), LL(pos->volume_pos), vtbl->count);
+	zft_resid = count < 0 ? -count : count;
+	TRACE_EXIT zft_resid ? -EINVAL : 0;
+}
+
+/* the following simply returns the raw data position of the EOM
+ * marker, MTIOCSIZE ioctl 
+ */
+__s64 zft_get_eom_pos(void)
+{
+	if (zft_qic_mode) {
+		return zft_calc_tape_pos(zft_eom_vtbl->start_seg);
+	} else {
+		/* there is only one volume in raw mode */
+		return zft_capacity;
+	}
+}
+
+/* skip to eom, used for MTEOM
+ */
+void zft_skip_to_eom(zft_position *pos)
+{
+	TRACE_FUN(ft_t_flow);
+	pos->seg_pos      = zft_eom_vtbl->start_seg;
+	pos->seg_byte_pos = 
+		pos->volume_pos     = 
+		zft_just_before_eof = 0;
+	pos->tape_pos = zft_calc_tape_pos(pos->seg_pos);
+	TRACE(ft_t_noise, "ftape positioned to segment %d, data pos " LL_X, 
+	      pos->seg_pos, LL(pos->tape_pos));
+	TRACE_EXIT;
+}
+
+/*  write an EOF-marker by setting zft_last_vtbl->end_seg to seg_pos.
+ *  NOTE: this function assumes that zft_last_vtbl points to a valid
+ *  vtbl entry
+ *
+ *  NOTE: this routine always positions before the EOF marker
+ */
+int zft_close_volume(zft_position *pos)
+{
+	TRACE_FUN(ft_t_any);
+
+	if (zft_vtbl_empty || !zft_last_vtbl->open) { /* should not happen */
+		TRACE(ft_t_noise, "There are no volumes to finish");
+		TRACE_EXIT -EIO;
+	}
+	if (pos->seg_byte_pos == 0 && 
+	    pos->seg_pos != zft_last_vtbl->start_seg) {
+		pos->seg_pos --;
+		pos->seg_byte_pos      = zft_get_seg_sz(pos->seg_pos);
+	}
+	zft_last_vtbl->end_seg   = pos->seg_pos;
+	zft_last_vtbl->size      = pos->volume_pos;
+	zft_volume_table_changed = 1;
+	zft_just_before_eof      = 1;
+	zft_eom_vtbl->start_seg  = zft_last_vtbl->end_seg + 1;
+	zft_last_vtbl->open      = 0; /* closed */
+	TRACE_EXIT 0;
+}
+
+/* write count file-marks at current position. 
+ *
+ *  The tape is positioned after the eof-marker, that is at byte 0 of
+ *  the segment following the eof-marker
+ *
+ *  this function is only allowed in zft_qic_mode
+ *
+ *  Only allowed when tape is at BOT or EOD.
+ */
+int zft_weof(unsigned int count, zft_position *pos)
+{
+	
+	TRACE_FUN(ft_t_flow);
+
+	if (!count) { /* write zero EOF marks should be a real no-op */
+		TRACE_EXIT 0;
+	}
+	zft_volume_table_changed = 1;
+	if (zft_tape_at_lbot(pos)) {
+		zft_init_vtbl();
+		if(zft_old_ftape) {
+			/* clear old ftape's eof marks */
+			zft_clear_ftape_file_marks();
+			zft_old_ftape = 0;    /* no longer old ftape */
+		}
+	}
+	if (zft_last_vtbl->open) {
+		zft_close_volume(pos);
+		zft_move_past_eof(pos);
+		count --;
+	}
+	/* now it's easy, just append eof-marks, that is empty
+	 * volumes, to the end of the already recorded media.
+	 */
+	while (count > 0 && 
+	       pos->seg_pos <= ft_last_data_segment && 
+	       zft_eom_vtbl->count < ZFT_MAX_VOLUMES) {
+		TRACE(ft_t_noise,
+		      "Writing zero sized file at segment %d", pos->seg_pos);
+		zft_new_vtbl_entry();
+		zft_last_vtbl->start_seg       = pos->seg_pos;
+		zft_last_vtbl->end_seg         = pos->seg_pos;
+		zft_last_vtbl->size            = 0;
+		zft_last_vtbl->blk_sz          = zft_blk_sz;
+		zft_last_vtbl->zft_volume      = 1;
+		zft_last_vtbl->use_compression = 0;
+		pos->tape_pos += zft_get_seg_sz(pos->seg_pos);
+		zft_eom_vtbl->start_seg = ++ pos->seg_pos;
+		count --;
+	} 
+	if (count > 0) {
+		/*  there are two possibilities: end of tape, or the
+		 *  maximum number of files is exhausted.
+		 */
+		zft_resid = count;
+		TRACE(ft_t_noise,"Number of marks NOT written: %d", zft_resid);
+		if (zft_eom_vtbl->count == ZFT_MAX_VOLUMES) {
+			TRACE_ABORT(-EINVAL, ft_t_warn,
+				    "maximum allowed number of files "
+				    "exhausted: %d", ZFT_MAX_VOLUMES);
+		} else {
+			TRACE_ABORT(-ENOSPC,
+				    ft_t_noise, "reached end of tape");
+		}
+	}
+	TRACE_EXIT 0;
+}
+
+const zft_volinfo *zft_find_volume(unsigned int seg_pos)
+{
+	TRACE_FUN(ft_t_flow);
+	
+	TRACE(ft_t_any, "called with seg_pos %d",seg_pos);
+	if (!zft_qic_mode) {
+		if (seg_pos > ft_last_data_segment) {
+			TRACE_EXIT &eot_vtbl;
+		}
+		tape_vtbl.blk_sz =  zft_blk_sz;
+		TRACE_EXIT &tape_vtbl;
+	}
+	if (seg_pos < zft_first_vtbl->start_seg) {
+		TRACE_EXIT (cur_vtbl = zft_first_vtbl);
+	}
+	while (seg_pos > cur_vtbl->end_seg) {
+		cur_vtbl = list_entry(cur_vtbl->node.next, zft_volinfo, node);
+		TRACE(ft_t_noise, "%d - %d", cur_vtbl->start_seg, cur_vtbl->end_seg);
+	}
+	while (seg_pos < cur_vtbl->start_seg) {
+		cur_vtbl = list_entry(cur_vtbl->node.prev, zft_volinfo, node);
+		TRACE(ft_t_noise, "%d - %d", cur_vtbl->start_seg, cur_vtbl->end_seg);
+	}
+	if (seg_pos > cur_vtbl->end_seg || seg_pos < cur_vtbl->start_seg) {
+		TRACE(ft_t_bug, "This cannot happen");
+	}
+	DUMP_VOLINFO(ft_t_noise, "", cur_vtbl);
+	TRACE_EXIT cur_vtbl;
+}
+
+/* this function really assumes that we are just before eof
+ */
+void zft_move_past_eof(zft_position *pos)
+{ 
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_noise, "old seg. pos: %d", pos->seg_pos);
+	pos->tape_pos += zft_get_seg_sz(pos->seg_pos++) - pos->seg_byte_pos;
+	pos->seg_byte_pos = 0;
+	pos->volume_pos   = 0;
+	if (zft_cmpr_ops) {
+		(*zft_cmpr_ops->reset)();
+	}
+	zft_just_before_eof =  0;
+	zft_deblock_segment = -1; /* no need to cache it anymore */
+	TRACE(ft_t_noise, "new seg. pos: %d", pos->seg_pos);
+	TRACE_EXIT;
+}
diff --git a/drivers/char/ftape/zftape/zftape-vtbl.h b/drivers/char/ftape/zftape/zftape-vtbl.h
new file mode 100644
index 0000000..f31d196
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-vtbl.h
@@ -0,0 +1,227 @@
+#ifndef _ZFTAPE_VTBL_H
+#define _ZFTAPE_VTBL_H
+
+/*
+ *      Copyright (c) 1995-1997  Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU General Public License as
+ published by the Free Software Foundation; either version 2, or (at
+ your option) any later version.
+ 
+ This program is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ General Public License for more details.
+ 
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139,
+ USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-vtbl.h,v $
+ * $Revision: 1.3 $
+ * $Date: 1997/10/28 14:30:09 $
+ *
+ *      This file defines a volume table as defined in the QIC-80
+ *      development standards.
+ */
+
+#include <linux/list.h>
+
+#include "../lowlevel/ftape-tracing.h"
+
+#include "../zftape/zftape-eof.h"
+#include "../zftape/zftape-ctl.h"
+#include "../zftape/zftape-rw.h"
+
+#define VTBL_SIZE 128 /* bytes */
+
+/* The following are offsets in the vtbl.  */
+#define VTBL_SIG   0
+#define VTBL_START 4
+#define VTBL_END   6
+#define VTBL_DESC  8
+#define VTBL_DATE  52
+#define VTBL_FLAGS 56
+#define VTBL_FL_VENDOR_SPECIFIC (1<<0)
+#define VTBL_FL_MUTLI_CARTRIDGE (1<<1)
+#define VTBL_FL_NOT_VERIFIED    (1<<2)
+#define VTBL_FL_REDIR_INHIBIT   (1<<3)
+#define VTBL_FL_SEG_SPANNING    (1<<4)
+#define VTBL_FL_DIRECTORY_LAST  (1<<5)
+#define VTBL_FL_RESERVED_6      (1<<6)
+#define VTBL_FL_RESERVED_7      (1<<7)
+#define VTBL_M_NO  57
+#define VTBL_EXT   58
+#define EXT_ZFTAPE_SIG     0
+#define EXT_ZFTAPE_BLKSZ  10
+#define EXT_ZFTAPE_CMAP   12
+#define EXT_ZFTAPE_QIC113 13
+#define VTBL_PWD   84
+#define VTBL_DIR_SIZE 92
+#define VTBL_DATA_SIZE 96
+#define VTBL_OS_VERSION 104
+#define VTBL_SRC_DRIVE  106
+#define VTBL_DEV        122
+#define VTBL_RESERVED_1 123
+#define VTBL_CMPR       124
+#define VTBL_CMPR_UNREG 0x3f
+#define VTBL_CMPR_USED  0x80
+#define VTBL_FMT        125
+#define VTBL_RESERVED_2 126
+#define VTBL_RESERVED_3 127
+/* compatibility with pre revision K */
+#define VTBL_K_CMPR     120 
+
+/*  the next is used by QIC-3020 tapes with format code 6 (>2^16
+ *  segments) It is specified in QIC-113, Rev. G, Section 5 (SCSI
+ *  volume table). The difference is simply, that we only store the
+ *  number of segments used, not the starting segment.
+ */
+#define VTBL_SCSI_SEGS  4 /* is a 4 byte value */
+
+/*  one vtbl is 128 bytes, that results in a maximum number of
+ *  29*1024/128 = 232 volumes.
+ */
+#define ZFT_MAX_VOLUMES (FT_SEGMENT_SIZE/VTBL_SIZE)
+#define VTBL_ID  "VTBL"
+#define VTBL_IDS { VTBL_ID, "XTBL", "UTID", "EXVT" } /* other valid ids */
+#define ZFT_VOL_NAME "zftape volume" /* volume label used by me */
+#define ZFTAPE_SIG "LINUX ZFT"
+
+/*  global variables
+ */
+typedef struct zft_internal_vtbl
+{
+	struct list_head node;
+	int          count;
+	unsigned int start_seg;         /* 32 bits are enough for now */
+	unsigned int end_seg;           /* 32 bits are enough for now */
+	__s64        size;              /* uncompressed size */
+        unsigned int blk_sz;            /* block size for this volume */
+	unsigned int zft_volume     :1; /* zftape created this volume */
+	unsigned int use_compression:1; /* compressed volume  */
+	unsigned int qic113         :1; /* layout of compressed block
+					 * info and vtbl conforms to
+					 * QIC-113, Rev. G 
+					 */
+	unsigned int new_volume     :1; /* it was created by us, this
+					 * run.  this allows the
+					 * fields that aren't really
+					 * used by zftape to be filled
+					 * in by some user level
+					 * program.
+					 */
+	unsigned int open           :1; /* just in progress of being 
+					 * written
+					 */
+} zft_volinfo;
+
+extern struct list_head zft_vtbl;
+#define zft_head_vtbl  list_entry(zft_vtbl.next, zft_volinfo, node)
+#define zft_eom_vtbl   list_entry(zft_vtbl.prev, zft_volinfo, node)
+#define zft_last_vtbl  list_entry(zft_eom_vtbl->node.prev, zft_volinfo, node)
+#define zft_first_vtbl list_entry(zft_head_vtbl->node.next, zft_volinfo, node)
+#define zft_vtbl_empty (zft_eom_vtbl->node.prev == &zft_head_vtbl->node)
+
+#define DUMP_VOLINFO(level, desc, info)					\
+{									\
+	char tmp[21];							\
+	strlcpy(tmp, desc, sizeof(tmp));				\
+	TRACE(level, "Volume %d:\n"					\
+	      KERN_INFO "description  : %s\n"				\
+	      KERN_INFO "first segment: %d\n"				\
+	      KERN_INFO "last  segment: %d\n"				\
+	      KERN_INFO "size         : " LL_X "\n"			\
+	      KERN_INFO "block size   : %d\n"				\
+	      KERN_INFO "compression  : %d\n"				\
+	      KERN_INFO "zftape volume: %d\n"				\
+	      KERN_INFO "QIC-113 conf.: %d",				\
+	      (info)->count, tmp, (info)->start_seg, (info)->end_seg,	\
+	      LL((info)->size), (info)->blk_sz,				\
+	      (info)->use_compression != 0, (info)->zft_volume != 0,	\
+	      (info)->qic113 != 0);					\
+}
+
+extern int zft_qic_mode;
+extern int zft_old_ftape;
+extern int zft_volume_table_changed;
+
+/* exported functions */
+extern void  zft_init_vtbl             (void);
+extern void  zft_free_vtbl             (void);
+extern int   zft_extract_volume_headers(__u8 *buffer);
+extern int   zft_update_volume_table   (unsigned int segment);
+extern int   zft_open_volume           (zft_position *pos,
+					int blk_sz, int use_compression);
+extern int   zft_close_volume          (zft_position *pos);
+extern const zft_volinfo *zft_find_volume(unsigned int seg_pos);
+extern int   zft_skip_volumes          (int count, zft_position *pos);
+extern __s64 zft_get_eom_pos           (void);
+extern void  zft_skip_to_eom           (zft_position *pos);
+extern int   zft_fake_volume_headers   (eof_mark_union *eof_map, 
+					int num_failed_sectors);
+extern int   zft_weof                  (unsigned int count, zft_position *pos);
+extern void  zft_move_past_eof         (zft_position *pos);
+
+static inline int   zft_tape_at_eod         (const zft_position *pos);
+static inline int   zft_tape_at_lbot        (const zft_position *pos);
+static inline void  zft_position_before_eof (zft_position *pos, 
+					     const zft_volinfo *volume);
+static inline __s64 zft_check_for_eof(const zft_volinfo *vtbl,
+				      const zft_position *pos);
+
+/* this function decrements the zft_seg_pos counter if we are right
+ * at the beginning of a segment. This is to handle fsfm/bsfm -- we
+ * need to position before the eof mark.  NOTE: zft_tape_pos is not
+ * changed 
+ */
+static inline void zft_position_before_eof(zft_position *pos, 
+					   const zft_volinfo *volume)
+{ 
+	TRACE_FUN(ft_t_flow);
+
+	if (pos->seg_pos == volume->end_seg + 1 &&  pos->seg_byte_pos == 0) {
+		pos->seg_pos --;
+		pos->seg_byte_pos = zft_get_seg_sz(pos->seg_pos);
+	}
+	TRACE_EXIT;
+}
+
+/*  Mmmh. Is the position at the end of the last volume, that is right
+ *  before the last EOF mark also logical an EOD condition?
+ */
+static inline int zft_tape_at_eod(const zft_position *pos)
+{ 
+	TRACE_FUN(ft_t_any);
+
+	if (zft_qic_mode) {
+		TRACE_EXIT (pos->seg_pos >= zft_eom_vtbl->start_seg ||
+			    zft_last_vtbl->open);
+	} else {
+		TRACE_EXIT pos->seg_pos > ft_last_data_segment;
+	}
+}
+
+static inline int zft_tape_at_lbot(const zft_position *pos)
+{
+	if (zft_qic_mode) {
+		return (pos->seg_pos <= zft_first_vtbl->start_seg &&
+			pos->volume_pos == 0);
+	} else {
+		return (pos->seg_pos <= ft_first_data_segment && 
+			pos->volume_pos == 0);
+	}
+}
+
+/* This one checks for EOF.  return remaing space (may be negative) 
+ */
+static inline __s64 zft_check_for_eof(const zft_volinfo *vtbl,
+				      const zft_position *pos)
+{     
+	return (__s64)(vtbl->size - pos->volume_pos);
+}
+
+#endif /* _ZFTAPE_VTBL_H */
diff --git a/drivers/char/ftape/zftape/zftape-write.c b/drivers/char/ftape/zftape/zftape-write.c
new file mode 100644
index 0000000..94327b8
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-write.c
@@ -0,0 +1,483 @@
+/*
+ *      Copyright (C) 1996, 1997 Claus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-write.c,v $
+ * $Revision: 1.3 $
+ * $Date: 1997/11/06 00:50:29 $
+ *
+ *      This file contains the writing code
+ *      for the QIC-117 floppy-tape driver for Linux.
+ */
+
+#include <linux/errno.h>
+#include <linux/mm.h>
+
+#include <linux/zftape.h>
+
+#include <asm/uaccess.h>
+
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-eof.h"
+#include "../zftape/zftape-ctl.h"
+#include "../zftape/zftape-write.h"
+#include "../zftape/zftape-read.h"
+#include "../zftape/zftape-rw.h"
+#include "../zftape/zftape-vtbl.h"
+
+/*      Global vars.
+ */
+
+/*      Local vars.
+ */
+static int last_write_failed;
+static int need_flush;
+
+void zft_prevent_flush(void)
+{
+	need_flush = 0;
+}
+
+static int zft_write_header_segments(__u8* buffer)
+{
+	int header_1_ok = 0;
+	int header_2_ok = 0;
+	unsigned int time_stamp;
+	TRACE_FUN(ft_t_noise);
+	
+	TRACE_CATCH(ftape_abort_operation(),);
+	ftape_seek_to_bot();    /* prevents extra rewind */
+	if (GET4(buffer, 0) != FT_HSEG_MAGIC) {
+		TRACE_ABORT(-EIO, ft_t_err,
+			    "wrong header signature found, aborting");
+	} 
+	/*   Be optimistic: */
+	PUT4(buffer, FT_SEG_CNT,
+	     zft_written_segments + GET4(buffer, FT_SEG_CNT) + 2);
+	if ((time_stamp = zft_get_time()) != 0) {
+		PUT4(buffer, FT_WR_DATE, time_stamp);
+		if (zft_label_changed) {
+			PUT4(buffer, FT_LABEL_DATE, time_stamp);
+		}
+	}
+	TRACE(ft_t_noise,
+	      "writing first header segment %d", ft_header_segment_1);
+	header_1_ok = zft_verify_write_segments(ft_header_segment_1, 
+						buffer, FT_SEGMENT_SIZE,
+						zft_deblock_buf) >= 0;
+	TRACE(ft_t_noise,
+	      "writing second header segment %d", ft_header_segment_2);
+	header_2_ok = zft_verify_write_segments(ft_header_segment_2, 
+						buffer, FT_SEGMENT_SIZE,
+						zft_deblock_buf) >= 0;
+	if (!header_1_ok) {
+		TRACE(ft_t_warn, "Warning: "
+		      "update of first header segment failed");
+	}
+	if (!header_2_ok) {
+		TRACE(ft_t_warn, "Warning: "
+		      "update of second header segment failed");
+	}
+	if (!header_1_ok && !header_2_ok) {
+		TRACE_ABORT(-EIO, ft_t_err, "Error: "
+		      "update of both header segments failed.");
+	}
+	TRACE_EXIT 0;
+}
+
+int zft_update_header_segments(void)
+{
+	TRACE_FUN(ft_t_noise);
+	
+	/*  must NOT use zft_write_protected, as it also includes the
+	 *  file access mode. But we also want to update when soft
+	 *  write protection is enabled (O_RDONLY)
+	 */
+	if (ft_write_protected || zft_old_ftape) {
+		TRACE_ABORT(0, ft_t_noise, "Tape set read-only: no update");
+	} 
+	if (!zft_header_read) {
+		TRACE_ABORT(0, ft_t_noise, "Nothing to update");
+	}
+	if (!zft_header_changed) {
+		zft_header_changed = zft_written_segments > 0;
+	}
+	if (!zft_header_changed && !zft_volume_table_changed) {
+		TRACE_ABORT(0, ft_t_noise, "Nothing to update");
+	}
+	TRACE(ft_t_noise, "Updating header segments");
+	if (ftape_get_status()->fti_state == writing) {
+		TRACE_CATCH(ftape_loop_until_writes_done(),);
+	}
+	TRACE_CATCH(ftape_abort_operation(),);
+	
+	zft_deblock_segment = -1; /* invalidate the cache */
+	if (zft_header_changed) {
+		TRACE_CATCH(zft_write_header_segments(zft_hseg_buf),);
+	}
+	if (zft_volume_table_changed) {
+		TRACE_CATCH(zft_update_volume_table(ft_first_data_segment),);
+	}
+	zft_header_changed =
+		zft_volume_table_changed = 
+		zft_label_changed        =
+		zft_written_segments     = 0;
+	TRACE_CATCH(ftape_abort_operation(),);
+	ftape_seek_to_bot();
+	TRACE_EXIT 0;
+}
+
+static int read_merge_buffer(int seg_pos, __u8 *buffer, int offset, int seg_sz)
+{
+	int result = 0;
+	const ft_trace_t old_tracing = TRACE_LEVEL;
+	TRACE_FUN(ft_t_flow);
+	
+	if (zft_qic_mode) {
+		/*  writing in the middle of a volume is NOT allowed
+		 *
+		 */
+		TRACE(ft_t_noise, "No need to read a segment");
+		memset(buffer + offset, 0, seg_sz - offset);
+		TRACE_EXIT 0;
+	}
+	TRACE(ft_t_any, "waiting");
+	ftape_start_writing(FT_WR_MULTI);
+	TRACE_CATCH(ftape_loop_until_writes_done(),);
+	
+	TRACE(ft_t_noise, "trying to read segment %d from offset %d",
+	      seg_pos, offset);
+	SET_TRACE_LEVEL(ft_t_bug);
+	result = zft_fetch_segment_fraction(seg_pos, buffer, 
+					    FT_RD_SINGLE,
+					    offset, seg_sz - offset);
+	SET_TRACE_LEVEL(old_tracing);
+	if (result != (seg_sz - offset)) {
+		TRACE(ft_t_noise, "Ignore error: read_segment() result: %d",
+		      result);
+		memset(buffer + offset, 0, seg_sz - offset);
+	}
+	TRACE_EXIT 0;
+}
+
+/* flush the write buffer to tape and write an eof-marker at the
+ * current position if not in raw mode.  This function always
+ * positions the tape before the eof-marker.  _ftape_close() should
+ * then advance to the next segment.
+ *
+ * the parameter "finish_volume" describes whether to position before
+ * or after the possibly created file-mark. We always position after
+ * the file-mark when called from ftape_close() and a flush was needed
+ * (that is ftape_write() was the last tape operation before calling
+ * ftape_flush) But we always position before the file-mark when this
+ * function get's called from outside ftape_close() 
+ */
+int zft_flush_buffers(void)
+{
+	int result;
+	int data_remaining;
+	int this_segs_size;
+	TRACE_FUN(ft_t_flow);
+
+	TRACE(ft_t_data_flow,
+	      "entered, ftape_state = %d", ftape_get_status()->fti_state);
+	if (ftape_get_status()->fti_state != writing && !need_flush) {
+		TRACE_ABORT(0, ft_t_noise, "no need for flush");
+	}
+	zft_io_state = zft_idle; /*  triggers some initializations for the
+				  *  read and write routines 
+				  */
+	if (last_write_failed) {
+		ftape_abort_operation();
+		TRACE_EXIT -EIO;
+	}
+	TRACE(ft_t_noise, "flushing write buffers");
+	this_segs_size = zft_get_seg_sz(zft_pos.seg_pos);
+	if (this_segs_size == zft_pos.seg_byte_pos) {
+		zft_pos.seg_pos ++;
+		data_remaining = zft_pos.seg_byte_pos = 0;
+	} else {
+		data_remaining = zft_pos.seg_byte_pos;
+	}
+	/* If there is any data not written to tape yet, append zero's
+	 * up to the end of the sector (if using compression) or merge
+	 * it with the data existing on the tape Then write the
+	 * segment(s) to tape.
+	 */
+	TRACE(ft_t_noise, "Position:\n"
+	      KERN_INFO "seg_pos  : %d\n"
+	      KERN_INFO "byte pos : %d\n"
+	      KERN_INFO "remaining: %d",
+	      zft_pos.seg_pos, zft_pos.seg_byte_pos, data_remaining);
+	if (data_remaining > 0) {
+		do {
+			this_segs_size = zft_get_seg_sz(zft_pos.seg_pos);
+			if (this_segs_size > data_remaining) {
+				TRACE_CATCH(read_merge_buffer(zft_pos.seg_pos,
+							      zft_deblock_buf,
+							      data_remaining,
+							      this_segs_size),
+					    last_write_failed = 1);
+			}
+			result = ftape_write_segment(zft_pos.seg_pos, 
+						     zft_deblock_buf,
+						     FT_WR_MULTI);
+			if (result != this_segs_size) {
+				TRACE(ft_t_err, "flush buffers failed");
+				zft_pos.tape_pos    -= zft_pos.seg_byte_pos;
+				zft_pos.seg_byte_pos = 0;
+
+				last_write_failed = 1;
+				TRACE_EXIT result;
+			}
+			zft_written_segments ++;
+			TRACE(ft_t_data_flow,
+			      "flush, moved out buffer: %d", result);
+			/* need next segment for more data (empty segments?)
+			 */
+			if (result < data_remaining) { 
+				if (result > 0) {       
+					/* move remainder to buffer beginning 
+					 */
+					memmove(zft_deblock_buf, 
+						zft_deblock_buf + result,
+						FT_SEGMENT_SIZE - result);
+				}
+			} 
+			data_remaining -= result;
+			zft_pos.seg_pos ++;
+		} while (data_remaining > 0);
+		TRACE(ft_t_any, "result: %d", result);
+		zft_deblock_segment = --zft_pos.seg_pos;
+		if (data_remaining == 0) {  /* first byte next segment */
+			zft_pos.seg_byte_pos = this_segs_size;
+		} else { /* after data previous segment, data_remaining < 0 */
+			zft_pos.seg_byte_pos = data_remaining + result;
+		}
+	} else {
+		TRACE(ft_t_noise, "zft_deblock_buf empty");
+		zft_pos.seg_pos --;
+		zft_pos.seg_byte_pos = zft_get_seg_sz (zft_pos.seg_pos);
+		ftape_start_writing(FT_WR_MULTI);
+	}
+	TRACE(ft_t_any, "waiting");
+	if ((result = ftape_loop_until_writes_done()) < 0) {
+		/* that's really bad. What to to with zft_tape_pos? 
+		 */
+		TRACE(ft_t_err, "flush buffers failed");
+	}
+	TRACE(ft_t_any, "zft_seg_pos: %d, zft_seg_byte_pos: %d",
+	      zft_pos.seg_pos, zft_pos.seg_byte_pos);
+	last_write_failed  =
+		need_flush = 0;
+	TRACE_EXIT result;
+}
+
+/* return-value: the number of bytes removed from the user-buffer
+ *
+ * out: 
+ *      int *write_cnt: how much actually has been moved to the
+ *                      zft_deblock_buf
+ *      int req_len  : MUST NOT BE CHANGED, except at EOT, in 
+ *                      which case it may be adjusted
+ * in : 
+ *      char *buff        : the user buffer
+ *      int buf_pos_write : copy of buf_len_wr int
+ *      this_segs_size    : the size in bytes of the actual segment
+ *                          char
+ *      *zft_deblock_buf   : zft_deblock_buf
+ */
+static int zft_simple_write(int *cnt,
+			    __u8 *dst_buf, const int seg_sz,
+			    const __u8 __user *src_buf, const int req_len, 
+			    const zft_position *pos,const zft_volinfo *volume)
+{
+	int space_left;
+	TRACE_FUN(ft_t_flow);
+
+	/* volume->size holds the tape capacity while volume is open */
+	if (pos->tape_pos + volume->blk_sz > volume->size) {
+		TRACE_EXIT -ENOSPC;
+	}
+	/*  remaining space in this segment, NOT zft_deblock_buf
+	 */
+	space_left = seg_sz - pos->seg_byte_pos;
+	*cnt = req_len < space_left ? req_len : space_left;
+	if (copy_from_user(dst_buf + pos->seg_byte_pos, src_buf, *cnt) != 0) {
+		TRACE_EXIT -EFAULT;
+	}
+	TRACE_EXIT *cnt;
+}
+
+static int check_write_access(int req_len,
+			      const zft_volinfo **volume,
+			      zft_position *pos,
+			      const unsigned int blk_sz)
+{
+	int result;
+	TRACE_FUN(ft_t_flow);
+
+	if ((req_len % zft_blk_sz) != 0) {
+		TRACE_ABORT(-EINVAL, ft_t_info,
+			    "write-count %d must be multiple of block-size %d",
+			    req_len, blk_sz);
+	}
+	if (zft_io_state == zft_writing) {
+		/*  all other error conditions have been checked earlier
+		 */
+		TRACE_EXIT 0;
+	}
+	zft_io_state = zft_idle;
+	TRACE_CATCH(zft_check_write_access(pos),);
+	/*  If we haven't read the header segment yet, do it now.
+	 *  This will verify the configuration, get the bad sector
+	 *  table and read the volume table segment 
+	 */
+	if (!zft_header_read) {
+		TRACE_CATCH(zft_read_header_segments(),);
+	}
+	/*  fine. Now the tape is either at BOT or at EOD,
+	 *  Write start of volume now
+	 */
+	TRACE_CATCH(zft_open_volume(pos, blk_sz, zft_use_compression),);
+	*volume = zft_find_volume(pos->seg_pos);
+	DUMP_VOLINFO(ft_t_noise, "", *volume);
+	zft_just_before_eof = 0;
+	/* now merge with old data if necessary */
+	if (!zft_qic_mode && pos->seg_byte_pos != 0){
+		result = zft_fetch_segment(pos->seg_pos,
+					   zft_deblock_buf,
+					   FT_RD_SINGLE);
+		if (result < 0) {
+			if (result == -EINTR || result == -ENOSPC) {
+				TRACE_EXIT result;
+			}
+			TRACE(ft_t_noise, 
+			      "ftape_read_segment() result: %d. "
+			      "This might be normal when using "
+			      "a newly\nformatted tape", result);
+			memset(zft_deblock_buf, '\0', pos->seg_byte_pos);
+		}
+	}
+	zft_io_state = zft_writing;
+	TRACE_EXIT 0;
+}
+
+static int fill_deblock_buf(__u8 *dst_buf, const int seg_sz,
+			    zft_position *pos, const zft_volinfo *volume,
+			    const char __user *usr_buf, const int req_len)
+{
+	int cnt = 0;
+	int result = 0;
+	TRACE_FUN(ft_t_flow);
+
+	if (seg_sz == 0) {
+		TRACE_ABORT(0, ft_t_data_flow, "empty segment");
+	}
+	TRACE(ft_t_data_flow, "\n"
+	      KERN_INFO "remaining req_len: %d\n"
+	      KERN_INFO "          buf_pos: %d", 
+	      req_len, pos->seg_byte_pos);
+	/* zft_deblock_buf will not contain a valid segment any longer */
+	zft_deblock_segment = -1;
+	if (zft_use_compression) {
+		TRACE_CATCH(zft_cmpr_lock(1 /* try to load */),);
+		TRACE_CATCH(result= (*zft_cmpr_ops->write)(&cnt,
+							   dst_buf, seg_sz,
+							   usr_buf, req_len,
+							   pos, volume),);
+	} else {
+		TRACE_CATCH(result= zft_simple_write(&cnt,
+						     dst_buf, seg_sz,
+						     usr_buf, req_len,
+						     pos, volume),);
+	}
+	pos->volume_pos   += result;
+	pos->seg_byte_pos += cnt;
+	pos->tape_pos     += cnt;
+	TRACE(ft_t_data_flow, "\n"
+	      KERN_INFO "removed from user-buffer : %d bytes.\n"
+	      KERN_INFO "copied to zft_deblock_buf: %d bytes.\n"
+	      KERN_INFO "zft_tape_pos             : " LL_X " bytes.",
+	      result, cnt, LL(pos->tape_pos));
+	TRACE_EXIT result;
+}
+
+
+/*  called by the kernel-interface routine "zft_write()"
+ */
+int _zft_write(const char __user *buff, int req_len)
+{
+	int result = 0;
+	int written = 0;
+	int write_cnt;
+	int seg_sz;
+	static const zft_volinfo *volume = NULL;
+	TRACE_FUN(ft_t_flow);
+	
+	zft_resid         = req_len;	
+	last_write_failed = 1; /* reset to 0 when successful */
+	/* check if write is allowed 
+	 */
+	TRACE_CATCH(check_write_access(req_len, &volume,&zft_pos,zft_blk_sz),);
+	while (req_len > 0) {
+		/* Allow us to escape from this loop with a signal !
+		 */
+		FT_SIGNAL_EXIT(_DONT_BLOCK);
+		seg_sz = zft_get_seg_sz(zft_pos.seg_pos);
+		if ((write_cnt = fill_deblock_buf(zft_deblock_buf,
+						  seg_sz,
+						  &zft_pos,
+						  volume,
+						  buff,
+						  req_len)) < 0) {
+			zft_resid -= written;
+			if (write_cnt == -ENOSPC) {
+				/* leave the remainder to flush_buffers()
+				 */
+				TRACE(ft_t_info, "No space left on device");
+				last_write_failed = 0;
+				if (!need_flush) {
+					need_flush = written > 0;
+				}
+				TRACE_EXIT written > 0 ? written : -ENOSPC;
+			} else {
+				TRACE_EXIT result;
+			}
+		}
+		if (zft_pos.seg_byte_pos == seg_sz) {
+			TRACE_CATCH(ftape_write_segment(zft_pos.seg_pos, 
+							zft_deblock_buf,
+							FT_WR_ASYNC),
+				    zft_resid -= written);
+			zft_written_segments ++;
+			zft_pos.seg_byte_pos =  0;
+			zft_deblock_segment  = zft_pos.seg_pos;
+			++zft_pos.seg_pos;
+		}
+		written += write_cnt;
+		buff    += write_cnt;
+		req_len -= write_cnt;
+	} /* while (req_len > 0) */
+	TRACE(ft_t_data_flow, "remaining in blocking buffer: %d",
+	       zft_pos.seg_byte_pos);
+	TRACE(ft_t_data_flow, "just written bytes: %d", written);
+	last_write_failed = 0;
+	zft_resid -= written;
+	need_flush = need_flush || written > 0;
+	TRACE_EXIT written;               /* bytes written */
+}
diff --git a/drivers/char/ftape/zftape/zftape-write.h b/drivers/char/ftape/zftape/zftape-write.h
new file mode 100644
index 0000000..ea88701
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape-write.h
@@ -0,0 +1,38 @@
+#ifndef _ZFTAPE_WRITE_H
+#define _ZFTAPE_WRITE_H
+
+/*
+ * Copyright (C) 1996, 1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-write.h,v $
+ * $Revision: 1.2 $
+ * $Date: 1997/10/05 19:19:13 $
+ *
+ *      This file contains the definitions for the write functions
+ *      for the zftape driver for Linux.
+ *
+ */
+
+extern int  zft_flush_buffers(void);
+extern int  zft_update_header_segments(void);
+extern void zft_prevent_flush(void);
+
+/*  hook for the VFS interface 
+ */
+extern int _zft_write(const char __user *buff, int req_len);
+#endif /* _ZFTAPE_WRITE_H */
diff --git a/drivers/char/ftape/zftape/zftape_syms.c b/drivers/char/ftape/zftape/zftape_syms.c
new file mode 100644
index 0000000..2db1401
--- /dev/null
+++ b/drivers/char/ftape/zftape/zftape_syms.c
@@ -0,0 +1,43 @@
+/*
+ *      Copyright (C) 1997 Claus-Justus Heine
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2, or (at your option)
+ any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING.  If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+ *
+ * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape_syms.c,v $
+ * $Revision: 1.3 $
+ * $Date: 1997/10/05 19:19:14 $
+ *
+ *      This file contains the symbols that the zftape frontend to 
+ *      the ftape floppy tape driver exports 
+ */		 
+
+#include <linux/module.h>
+
+#include <linux/zftape.h>
+
+#include "../zftape/zftape-init.h"
+#include "../zftape/zftape-read.h"
+#include "../zftape/zftape-buffers.h"
+#include "../zftape/zftape-ctl.h"
+
+/* zftape-init.c */
+EXPORT_SYMBOL(zft_cmpr_register);
+/* zftape-read.c */
+EXPORT_SYMBOL(zft_fetch_segment_fraction);
+/* zftape-buffers.c */
+EXPORT_SYMBOL(zft_vmalloc_once);
+EXPORT_SYMBOL(zft_vmalloc_always);
+EXPORT_SYMBOL(zft_vfree);