1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/tty.h>
 3#include <linux/module.h>
 4#include <linux/kallsyms.h>
 5#include <linux/semaphore.h>
 6#include <linux/sched.h>
 7#include "tty.h"
 8
 9/* Legacy tty mutex glue */
10
11/*
12 * Getting the big tty mutex.
13 */
14
15void tty_lock(struct tty_struct *tty)
16{
 
 
17	tty_kref_get(tty);
18	mutex_lock(&tty->legacy_mutex);
19}
20EXPORT_SYMBOL(tty_lock);
21
22int tty_lock_interruptible(struct tty_struct *tty)
23{
24	int ret;
25
 
 
26	tty_kref_get(tty);
27	ret = mutex_lock_interruptible(&tty->legacy_mutex);
28	if (ret)
29		tty_kref_put(tty);
30	return ret;
31}
32
33void tty_unlock(struct tty_struct *tty)
34{
 
 
35	mutex_unlock(&tty->legacy_mutex);
36	tty_kref_put(tty);
37}
38EXPORT_SYMBOL(tty_unlock);
39
40void tty_lock_slave(struct tty_struct *tty)
41{
42	if (tty && tty != tty->link)
43		tty_lock(tty);
44}
45
46void tty_unlock_slave(struct tty_struct *tty)
47{
48	if (tty && tty != tty->link)
49		tty_unlock(tty);
50}
51
52void tty_set_lock_subclass(struct tty_struct *tty)
53{
54	lockdep_set_subclass(&tty->legacy_mutex, TTY_LOCK_SLAVE);
55}

 1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/tty.h>
 3#include <linux/module.h>
 4#include <linux/kallsyms.h>
 5#include <linux/semaphore.h>
 6#include <linux/sched.h>
 7#include "tty.h"
 8
 9/* Legacy tty mutex glue */
10
11/*
12 * Getting the big tty mutex.
13 */
14
15void tty_lock(struct tty_struct *tty)
16{
17	if (WARN(tty->magic != TTY_MAGIC, "L Bad %p\n", tty))
18		return;
19	tty_kref_get(tty);
20	mutex_lock(&tty->legacy_mutex);
21}
22EXPORT_SYMBOL(tty_lock);
23
24int tty_lock_interruptible(struct tty_struct *tty)
25{
26	int ret;
27
28	if (WARN(tty->magic != TTY_MAGIC, "L Bad %p\n", tty))
29		return -EIO;
30	tty_kref_get(tty);
31	ret = mutex_lock_interruptible(&tty->legacy_mutex);
32	if (ret)
33		tty_kref_put(tty);
34	return ret;
35}
36
37void tty_unlock(struct tty_struct *tty)
38{
39	if (WARN(tty->magic != TTY_MAGIC, "U Bad %p\n", tty))
40		return;
41	mutex_unlock(&tty->legacy_mutex);
42	tty_kref_put(tty);
43}
44EXPORT_SYMBOL(tty_unlock);
45
46void tty_lock_slave(struct tty_struct *tty)
47{
48	if (tty && tty != tty->link)
49		tty_lock(tty);
50}
51
52void tty_unlock_slave(struct tty_struct *tty)
53{
54	if (tty && tty != tty->link)
55		tty_unlock(tty);
56}
57
58void tty_set_lock_subclass(struct tty_struct *tty)
59{
60	lockdep_set_subclass(&tty->legacy_mutex, TTY_LOCK_SLAVE);
61}