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/include/linux/tty.h b/include/linux/tty.h
index 2699298..c36a76d 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -177,9 +177,13 @@
* size each time the window is created or resized anyway.
* - TYT, 9/14/92
*/
+
+struct tty_operations;
+
struct tty_struct {
int magic;
struct tty_driver *driver;
+ const struct tty_operations *ops;
int index;
struct tty_ldisc ldisc;
struct mutex termios_mutex;
@@ -295,6 +299,10 @@
extern int tty_read_raw_data(struct tty_struct *tty, unsigned char *bufp,
int buflen);
extern void tty_write_message(struct tty_struct *tty, char *msg);
+extern int tty_put_char(struct tty_struct *tty, unsigned char c);
+extern int tty_chars_in_buffer(struct tty_struct *tty);
+extern int tty_write_room(struct tty_struct *tty);
+extern void tty_driver_flush_buffer(struct tty_struct *tty);
extern int is_current_pgrp_orphaned(void);
extern struct pid *tty_get_pgrp(struct tty_struct *tty);