| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /*  devfs (Device FileSystem) utilities. | 
|  | 2 |  | 
|  | 3 | Copyright (C) 1999-2002  Richard Gooch | 
|  | 4 |  | 
|  | 5 | This library is free software; you can redistribute it and/or | 
|  | 6 | modify it under the terms of the GNU Library General Public | 
|  | 7 | License as published by the Free Software Foundation; either | 
|  | 8 | version 2 of the License, or (at your option) any later version. | 
|  | 9 |  | 
|  | 10 | This library is distributed in the hope that it will be useful, | 
|  | 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU | 
|  | 13 | Library General Public License for more details. | 
|  | 14 |  | 
|  | 15 | You should have received a copy of the GNU Library General Public | 
|  | 16 | License along with this library; if not, write to the Free | 
|  | 17 | Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | 
|  | 18 |  | 
|  | 19 | Richard Gooch may be reached by email at  rgooch@atnf.csiro.au | 
|  | 20 | The postal address is: | 
|  | 21 | Richard Gooch, c/o ATNF, P. O. Box 76, Epping, N.S.W., 2121, Australia. | 
|  | 22 |  | 
|  | 23 | ChangeLog | 
|  | 24 |  | 
|  | 25 | 19991031   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 26 | Created. | 
|  | 27 | 19991103   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 28 | Created <_devfs_convert_name> and supported SCSI and IDE CD-ROMs | 
|  | 29 | 20000203   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 30 | Changed operations pointer type to void *. | 
|  | 31 | 20000621   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 32 | Changed interface to <devfs_register_series>. | 
|  | 33 | 20000622   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 34 | Took account of interface change to <devfs_mk_symlink>. | 
|  | 35 | Took account of interface change to <devfs_mk_dir>. | 
|  | 36 | 20010519   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 37 | Documentation cleanup. | 
|  | 38 | 20010709   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 39 | Created <devfs_*alloc_major> and <devfs_*alloc_devnum>. | 
|  | 40 | 20010710   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 41 | Created <devfs_*alloc_unique_number>. | 
|  | 42 | 20010730   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 43 | Documentation typo fix. | 
|  | 44 | 20010806   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 45 | Made <block_semaphore> and <char_semaphore> private. | 
|  | 46 | 20010813   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 47 | Fixed bug in <devfs_alloc_unique_number>: limited to 128 numbers | 
|  | 48 | 20010818   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 49 | Updated major masks up to Linus' "no new majors" proclamation. | 
|  | 50 | Block: were 126 now 122 free, char: were 26 now 19 free. | 
|  | 51 | 20020324   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 52 | Fixed bug in <devfs_alloc_unique_number>: was clearing beyond | 
|  | 53 | bitfield. | 
|  | 54 | 20020326   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 55 | Fixed bitfield data type for <devfs_*alloc_devnum>. | 
|  | 56 | Made major bitfield type and initialiser 64 bit safe. | 
|  | 57 | 20020413   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 58 | Fixed shift warning on 64 bit machines. | 
|  | 59 | 20020428   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 60 | Copied and used macro for error messages from fs/devfs/base.c | 
|  | 61 | 20021013   Richard Gooch <rgooch@atnf.csiro.au> | 
|  | 62 | Documentation fix. | 
|  | 63 | 20030101   Adam J. Richter <adam@yggdrasil.com> | 
|  | 64 | Eliminate DEVFS_SPECIAL_{CHR,BLK}.  Use mode_t instead. | 
|  | 65 | 20030106   Christoph Hellwig <hch@infradead.org> | 
|  | 66 | Rewrite devfs_{,de}alloc_devnum to look like C code. | 
|  | 67 | */ | 
|  | 68 | #include <linux/module.h> | 
|  | 69 | #include <linux/init.h> | 
|  | 70 | #include <linux/devfs_fs_kernel.h> | 
|  | 71 | #include <linux/slab.h> | 
|  | 72 | #include <linux/vmalloc.h> | 
|  | 73 | #include <linux/genhd.h> | 
|  | 74 | #include <linux/bitops.h> | 
|  | 75 |  | 
|  | 76 | int devfs_register_tape(const char *name) | 
|  | 77 | { | 
|  | 78 | char tname[32], dest[64]; | 
|  | 79 | static unsigned int tape_counter; | 
|  | 80 | unsigned int n = tape_counter++; | 
|  | 81 |  | 
|  | 82 | sprintf(dest, "../%s", name); | 
|  | 83 | sprintf(tname, "tapes/tape%u", n); | 
|  | 84 | devfs_mk_symlink(tname, dest); | 
|  | 85 |  | 
|  | 86 | return n; | 
|  | 87 | } | 
|  | 88 |  | 
|  | 89 | EXPORT_SYMBOL(devfs_register_tape); | 
|  | 90 |  | 
|  | 91 | void devfs_unregister_tape(int num) | 
|  | 92 | { | 
|  | 93 | if (num >= 0) | 
|  | 94 | devfs_remove("tapes/tape%u", num); | 
|  | 95 | } | 
|  | 96 |  | 
|  | 97 | EXPORT_SYMBOL(devfs_unregister_tape); |