tty: move some internal tty lock enums and functions out of tty.h

Move the TTY_LOCK_* enums and tty_ldisc lock functions out of the global
tty.h into the local header file to clean things up.

Cc: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20210408125134.3016837-10-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Greg Kroah-Hartman 2021-04-08 14:51:30 +02:00
parent da5d669e00
commit 6c80c0b94b
4 changed files with 28 additions and 27 deletions

View File

@ -17,6 +17,32 @@
#define tty_info_ratelimited(tty, f, ...) \
tty_msg(pr_info_ratelimited, tty, f, ##__VA_ARGS__)
/*
* Lock subclasses for tty locks
*
* TTY_LOCK_NORMAL is for normal ttys and master ptys.
* TTY_LOCK_SLAVE is for slave ptys only.
*
* Lock subclasses are necessary for handling nested locking with pty pairs.
* tty locks which use nested locking:
*
* legacy_mutex - Nested tty locks are necessary for releasing pty pairs.
* The stable lock order is master pty first, then slave pty.
* termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem.
* Subclassing this lock enables the slave pty to hold its
* termios_rwsem when claiming the master tty_buffer lock.
* tty_buffer lock - slave ptys can claim nested buffer lock when handling
* signal chars. The stable lock order is slave pty, then
* master.
*/
enum {
TTY_LOCK_NORMAL = 0,
TTY_LOCK_SLAVE,
};
int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout);
void tty_ldisc_unlock(struct tty_struct *tty);
/* tty_audit.c */
#ifdef CONFIG_AUDIT
void tty_audit_add_data(struct tty_struct *tty, const void *data, size_t size);

View File

@ -17,7 +17,7 @@
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/ratelimit.h>
#include "tty.h"
#define MIN_TTYB_SIZE 256
#define TTYB_ALIGN_MASK 255

View File

@ -4,6 +4,7 @@
#include <linux/kallsyms.h>
#include <linux/semaphore.h>
#include <linux/sched.h>
#include "tty.h"
/* Legacy tty mutex glue */

View File

@ -16,30 +16,6 @@
#include <linux/llist.h>
/*
* Lock subclasses for tty locks
*
* TTY_LOCK_NORMAL is for normal ttys and master ptys.
* TTY_LOCK_SLAVE is for slave ptys only.
*
* Lock subclasses are necessary for handling nested locking with pty pairs.
* tty locks which use nested locking:
*
* legacy_mutex - Nested tty locks are necessary for releasing pty pairs.
* The stable lock order is master pty first, then slave pty.
* termios_rwsem - The stable lock order is tty_buffer lock->termios_rwsem.
* Subclassing this lock enables the slave pty to hold its
* termios_rwsem when claiming the master tty_buffer lock.
* tty_buffer lock - slave ptys can claim nested buffer lock when handling
* signal chars. The stable lock order is slave pty, then
* master.
*/
enum {
TTY_LOCK_NORMAL = 0,
TTY_LOCK_SLAVE,
};
/*
* (Note: the *_driver.minor_start values 1, 64, 128, 192 are
* hardcoded at present.)
@ -419,8 +395,6 @@ extern struct tty_struct *tty_kopen_exclusive(dev_t device);
extern struct tty_struct *tty_kopen_shared(dev_t device);
extern void tty_kclose(struct tty_struct *tty);
extern int tty_dev_name_to_number(const char *name, dev_t *number);
extern int tty_ldisc_lock(struct tty_struct *tty, unsigned long timeout);
extern void tty_ldisc_unlock(struct tty_struct *tty);
extern ssize_t redirected_tty_write(struct kiocb *, struct iov_iter *);
extern struct file *tty_release_redirect(struct tty_struct *tty);
#else