tty: The big operations rework
- Operations are now a shared const function block as with most other Linux
objects
- Introduce wrappers for some optional functions to get consistent behaviour
- Wrap put_char which used to be patched by the tty layer
- Document which functions are needed/optional
- Make put_char report success/fail
- Cache the driver->ops pointer in the tty as tty->ops
- Remove various surplus lock calls we no longer need
- Remove proc_write method as noted by Alexey Dobriyan
- Introduce some missing sanity checks where certain driver/ldisc
combinations would oops as they didn't check needed methods were present
[akpm@linux-foundation.org: fix fs/compat_ioctl.c build]
[akpm@linux-foundation.org: fix isicom]
[akpm@linux-foundation.org: fix arch/ia64/hp/sim/simserial.c build]
[akpm@linux-foundation.org: fix kgdb]
Signed-off-by: Alan Cox <alan@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/char/n_hdlc.c b/drivers/char/n_hdlc.c
index a07c0af..a35bfd7 100644
--- a/drivers/char/n_hdlc.c
+++ b/drivers/char/n_hdlc.c
@@ -342,12 +342,10 @@
#endif
/* Flush any pending characters in the driver and discipline. */
-
if (tty->ldisc.flush_buffer)
- tty->ldisc.flush_buffer (tty);
+ tty->ldisc.flush_buffer(tty);
- if (tty->driver->flush_buffer)
- tty->driver->flush_buffer (tty);
+ tty_driver_flush_buffer(tty);
if (debuglevel >= DEBUG_LEVEL_INFO)
printk("%s(%d)n_hdlc_tty_open() success\n",__FILE__,__LINE__);
@@ -399,7 +397,7 @@
/* Send the next block of data to device */
tty->flags |= (1 << TTY_DO_WRITE_WAKEUP);
- actual = tty->driver->write(tty, tbuf->buf, tbuf->count);
+ actual = tty->ops->write(tty, tbuf->buf, tbuf->count);
/* rollback was possible and has been done */
if (actual == -ERESTARTSYS) {
@@ -752,8 +750,7 @@
case TIOCOUTQ:
/* get the pending tx byte count in the driver */
- count = tty->driver->chars_in_buffer ?
- tty->driver->chars_in_buffer(tty) : 0;
+ count = tty_chars_in_buffer(tty);
/* add size of next output frame in queue */
spin_lock_irqsave(&n_hdlc->tx_buf_list.spinlock,flags);
if (n_hdlc->tx_buf_list.head)