Commit | Line | Data |
---|---|---|
b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
b07471fa AB |
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 | ||
89c8d91e AC |
8 | /* Legacy tty mutex glue */ |
9 | ||
b07471fa AB |
10 | /* |
11 | * Getting the big tty mutex. | |
12 | */ | |
89c8d91e | 13 | |
c2bb524b | 14 | void tty_lock(struct tty_struct *tty) |
b07471fa | 15 | { |
6d029c68 | 16 | if (WARN(tty->magic != TTY_MAGIC, "L Bad %p\n", tty)) |
89c8d91e | 17 | return; |
89c8d91e | 18 | tty_kref_get(tty); |
2febdb63 | 19 | mutex_lock(&tty->legacy_mutex); |
b07471fa AB |
20 | } |
21 | EXPORT_SYMBOL(tty_lock); | |
22 | ||
0bfd464d PH |
23 | int tty_lock_interruptible(struct tty_struct *tty) |
24 | { | |
e9036d06 PH |
25 | int ret; |
26 | ||
0bfd464d PH |
27 | if (WARN(tty->magic != TTY_MAGIC, "L Bad %p\n", tty)) |
28 | return -EIO; | |
29 | tty_kref_get(tty); | |
e9036d06 PH |
30 | ret = mutex_lock_interruptible(&tty->legacy_mutex); |
31 | if (ret) | |
32 | tty_kref_put(tty); | |
33 | return ret; | |
0bfd464d PH |
34 | } |
35 | ||
c2bb524b | 36 | void tty_unlock(struct tty_struct *tty) |
b07471fa | 37 | { |
6d029c68 | 38 | if (WARN(tty->magic != TTY_MAGIC, "U Bad %p\n", tty)) |
89c8d91e | 39 | return; |
89c8d91e AC |
40 | mutex_unlock(&tty->legacy_mutex); |
41 | tty_kref_put(tty); | |
b07471fa AB |
42 | } |
43 | EXPORT_SYMBOL(tty_unlock); | |
89c8d91e | 44 | |
c2bb524b | 45 | void tty_lock_slave(struct tty_struct *tty) |
89c8d91e | 46 | { |
eef15e2a | 47 | if (tty && tty != tty->link) |
2febdb63 | 48 | tty_lock(tty); |
89c8d91e | 49 | } |
89c8d91e | 50 | |
c2bb524b | 51 | void tty_unlock_slave(struct tty_struct *tty) |
89c8d91e | 52 | { |
2aff5e2b PH |
53 | if (tty && tty != tty->link) |
54 | tty_unlock(tty); | |
89c8d91e | 55 | } |
2febdb63 PH |
56 | |
57 | void tty_set_lock_subclass(struct tty_struct *tty) | |
58 | { | |
3abf87cd | 59 | lockdep_set_subclass(&tty->legacy_mutex, TTY_LOCK_SLAVE); |
2febdb63 | 60 | } |