diff options
Diffstat (limited to 'drivers/tty/tty_mutex.c')
| -rw-r--r-- | drivers/tty/tty_mutex.c | 19 | 
1 files changed, 15 insertions, 4 deletions
diff --git a/drivers/tty/tty_mutex.c b/drivers/tty/tty_mutex.c index 69adc80c98c..67feac9e6eb 100644 --- a/drivers/tty/tty_mutex.c +++ b/drivers/tty/tty_mutex.c @@ -6,11 +6,17 @@  /* Legacy tty mutex glue */ +enum { +	TTY_MUTEX_NORMAL, +	TTY_MUTEX_NESTED, +}; +  /*   * Getting the big tty mutex.   */ -void __lockfunc tty_lock(struct tty_struct *tty) +static void __lockfunc tty_lock_nested(struct tty_struct *tty, +				       unsigned int subclass)  {  	if (tty->magic != TTY_MAGIC) {  		printk(KERN_ERR "L Bad %p\n", tty); @@ -18,7 +24,12 @@ void __lockfunc tty_lock(struct tty_struct *tty)  		return;  	}  	tty_kref_get(tty); -	mutex_lock(&tty->legacy_mutex); +	mutex_lock_nested(&tty->legacy_mutex, subclass); +} + +void __lockfunc tty_lock(struct tty_struct *tty) +{ +	return tty_lock_nested(tty, TTY_MUTEX_NORMAL);  }  EXPORT_SYMBOL(tty_lock); @@ -43,11 +54,11 @@ void __lockfunc tty_lock_pair(struct tty_struct *tty,  {  	if (tty < tty2) {  		tty_lock(tty); -		tty_lock(tty2); +		tty_lock_nested(tty2, TTY_MUTEX_NESTED);  	} else {  		if (tty2 && tty2 != tty)  			tty_lock(tty2); -		tty_lock(tty); +		tty_lock_nested(tty, TTY_MUTEX_NESTED);  	}  }  EXPORT_SYMBOL(tty_lock_pair);  |