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 void __lockfunc tty_unlock(struct tty_struct *tty) 23 { 24 if (WARN(tty->magic != TTY_MAGIC, "U Bad %p\n", tty)) 25 return; 26 mutex_unlock(&tty->legacy_mutex); 27 tty_kref_put(tty); 28 } 29 EXPORT_SYMBOL(tty_unlock); 30 31 void __lockfunc tty_lock_slave(struct tty_struct *tty) 32 { 33 if (tty && tty != tty->link) 34 tty_lock(tty); 35 } 36 37 void __lockfunc tty_unlock_slave(struct tty_struct *tty) 38 { 39 if (tty && tty != tty->link) 40 tty_unlock(tty); 41 } 42 43 void tty_set_lock_subclass(struct tty_struct *tty) 44 { 45 lockdep_set_subclass(&tty->legacy_mutex, TTY_LOCK_SLAVE); 46 } 47