[linux-2.6-block.git] / drivers / tty / tty_mutex.c

#include <linux/tty.h>
#include <linux/module.h>
#include <linux/kallsyms.h>
#include <linux/semaphore.h>
#include <linux/sched.h>

/* Legacy tty mutex glue */

/*
 * Getting the big tty mutex.
 */

void tty_lock(struct tty_struct *tty)
{
	if (WARN(tty->magic != TTY_MAGIC, "L Bad %p\n", tty))
		return;
	tty_kref_get(tty);
	mutex_lock(&tty->legacy_mutex);
}
EXPORT_SYMBOL(tty_lock);

int tty_lock_interruptible(struct tty_struct *tty)
{
	int ret;

	if (WARN(tty->magic != TTY_MAGIC, "L Bad %p\n", tty))
		return -EIO;
	tty_kref_get(tty);
	ret = mutex_lock_interruptible(&tty->legacy_mutex);
	if (ret)
		tty_kref_put(tty);
	return ret;
}

void tty_unlock(struct tty_struct *tty)
{
	if (WARN(tty->magic != TTY_MAGIC, "U Bad %p\n", tty))
		return;
	mutex_unlock(&tty->legacy_mutex);
	tty_kref_put(tty);
}
EXPORT_SYMBOL(tty_unlock);

void tty_lock_slave(struct tty_struct *tty)
{
	if (tty && tty != tty->link)
		tty_lock(tty);
}

void tty_unlock_slave(struct tty_struct *tty)
{
	if (tty && tty != tty->link)
		tty_unlock(tty);
}

void tty_set_lock_subclass(struct tty_struct *tty)
{
	lockdep_set_subclass(&tty->legacy_mutex, TTY_LOCK_SLAVE);
}
Commit	Line	Data
b07471fa AB	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
89c8d91e AC	7	/* Legacy tty mutex glue */
89c8d91e AC	8
b07471fa AB	9	/*
	10	* Getting the big tty mutex.
	11	*/
89c8d91e	12
c2bb524b	13	void tty_lock(struct tty_struct *tty)
b07471fa	14	{
6d029c68	15	if (WARN(tty->magic != TTY_MAGIC, "L Bad %p\n", tty))
89c8d91e	16	return;
89c8d91e	17	tty_kref_get(tty);
2febdb63	18	mutex_lock(&tty->legacy_mutex);
b07471fa AB	19	}
	20	EXPORT_SYMBOL(tty_lock);
	21
0bfd464d PH	22	int tty_lock_interruptible(struct tty_struct *tty)
0bfd464d PH	23	{
e9036d06 PH	24	int ret;
e9036d06 PH	25
0bfd464d PH	26	if (WARN(tty->magic != TTY_MAGIC, "L Bad %p\n", tty))
	27	return -EIO;
	28	tty_kref_get(tty);
e9036d06 PH	29	ret = mutex_lock_interruptible(&tty->legacy_mutex);
	30	if (ret)
	31	tty_kref_put(tty);
	32	return ret;
0bfd464d PH	33	}
0bfd464d PH	34
c2bb524b	35	void tty_unlock(struct tty_struct *tty)
b07471fa	36	{
6d029c68	37	if (WARN(tty->magic != TTY_MAGIC, "U Bad %p\n", tty))
89c8d91e	38	return;
89c8d91e AC	39	mutex_unlock(&tty->legacy_mutex);
89c8d91e AC	40	tty_kref_put(tty);
b07471fa AB	41	}
b07471fa AB	42	EXPORT_SYMBOL(tty_unlock);
89c8d91e	43
c2bb524b	44	void tty_lock_slave(struct tty_struct *tty)
89c8d91e	45	{
eef15e2a	46	if (tty && tty != tty->link)
2febdb63	47	tty_lock(tty);
89c8d91e	48	}
89c8d91e	49
c2bb524b	50	void tty_unlock_slave(struct tty_struct *tty)
89c8d91e	51	{
2aff5e2b PH	52	if (tty && tty != tty->link)
2aff5e2b PH	53	tty_unlock(tty);
89c8d91e	54	}
2febdb63 PH	55
	56	void tty_set_lock_subclass(struct tty_struct *tty)
	57	{
3abf87cd	58	lockdep_set_subclass(&tty->legacy_mutex, TTY_LOCK_SLAVE);
2febdb63	59	}