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