[mirror_ubuntu-artful-kernel.git] / include / linux / wait.h

#ifndef _LINUX_WAIT_H
#define _LINUX_WAIT_H

#define WNOHANG		0x00000001
#define WUNTRACED	0x00000002
#define WSTOPPED	WUNTRACED
#define WEXITED		0x00000004
#define WCONTINUED	0x00000008
#define WNOWAIT		0x01000000	/* Don't reap, just poll status.  */

#define __WNOTHREAD	0x20000000	/* Don't wait on children of other threads in this group */
#define __WALL		0x40000000	/* Wait on all children, regardless of type */
#define __WCLONE	0x80000000	/* Wait only on non-SIGCHLD children */

/* First argument to waitid: */
#define P_ALL		0
#define P_PID		1
#define P_PGID		2

#ifdef __KERNEL__

#include <linux/list.h>
#include <linux/stddef.h>
#include <linux/spinlock.h>
#include <asm/system.h>
#include <asm/current.h>

typedef struct __wait_queue wait_queue_t;
typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int sync, void *key);
int default_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);

struct __wait_queue {
	unsigned int flags;
#define WQ_FLAG_EXCLUSIVE	0x01
	void *private;
	wait_queue_func_t func;
	struct list_head task_list;
};

struct wait_bit_key {
	void *flags;
	int bit_nr;
};

struct wait_bit_queue {
	struct wait_bit_key key;
	wait_queue_t wait;
};

struct __wait_queue_head {
	spinlock_t lock;
	struct list_head task_list;
};
typedef struct __wait_queue_head wait_queue_head_t;

struct task_struct;

/*
 * Macros for declaration and initialisaton of the datatypes
 */

#define __WAITQUEUE_INITIALIZER(name, tsk) {				\
	.private	= tsk,						\
	.func		= default_wake_function,			\
	.task_list	= { NULL, NULL } }

#define DECLARE_WAITQUEUE(name, tsk)					\
	wait_queue_t name = __WAITQUEUE_INITIALIZER(name, tsk)

#define __WAIT_QUEUE_HEAD_INITIALIZER(name) {				\
	.lock		= __SPIN_LOCK_UNLOCKED(name.lock),		\
	.task_list	= { &(name).task_list, &(name).task_list } }

#define DECLARE_WAIT_QUEUE_HEAD(name) \
	wait_queue_head_t name = __WAIT_QUEUE_HEAD_INITIALIZER(name)

#define __WAIT_BIT_KEY_INITIALIZER(word, bit)				\
	{ .flags = word, .bit_nr = bit, }

extern void init_waitqueue_head(wait_queue_head_t *q);

#ifdef CONFIG_LOCKDEP
# define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
	({ init_waitqueue_head(&name); name; })
# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
	wait_queue_head_t name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
#else
# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
#endif

static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p)
{
	q->flags = 0;
	q->private = p;
	q->func = default_wake_function;
}

static inline void init_waitqueue_func_entry(wait_queue_t *q,
					wait_queue_func_t func)
{
	q->flags = 0;
	q->private = NULL;
	q->func = func;
}

static inline int waitqueue_active(wait_queue_head_t *q)
{
	return !list_empty(&q->task_list);
}

extern void add_wait_queue(wait_queue_head_t *q, wait_queue_t *wait);
extern void add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t *wait);
extern void remove_wait_queue(wait_queue_head_t *q, wait_queue_t *wait);

static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new)
{
	list_add(&new->task_list, &head->task_list);
}

/*
 * Used for wake-one threads:
 */
static inline void __add_wait_queue_tail(wait_queue_head_t *head,
						wait_queue_t *new)
{
	list_add_tail(&new->task_list, &head->task_list);
}

static inline void __remove_wait_queue(wait_queue_head_t *head,
							wait_queue_t *old)
{
	list_del(&old->task_list);
}

void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
			int nr_exclusive, int sync, void *key);
void __wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key);
void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key);
void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr,
			void *key);
void __wake_up_locked(wait_queue_head_t *q, unsigned int mode);
void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr);
void __wake_up_bit(wait_queue_head_t *, void *, int);
int __wait_on_bit(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned);
int __wait_on_bit_lock(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned);
void wake_up_bit(void *, int);
int out_of_line_wait_on_bit(void *, int, int (*)(void *), unsigned);
int out_of_line_wait_on_bit_lock(void *, int, int (*)(void *), unsigned);
wait_queue_head_t *bit_waitqueue(void *, int);

#define wake_up(x)			__wake_up(x, TASK_NORMAL, 1, NULL)
#define wake_up_nr(x, nr)		__wake_up(x, TASK_NORMAL, nr, NULL)
#define wake_up_all(x)			__wake_up(x, TASK_NORMAL, 0, NULL)
#define wake_up_locked(x)		__wake_up_locked((x), TASK_NORMAL)

#define wake_up_interruptible(x)	__wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
#define wake_up_interruptible_nr(x, nr)	__wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
#define wake_up_interruptible_all(x)	__wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
#define wake_up_interruptible_sync(x)	__wake_up_sync((x), TASK_INTERRUPTIBLE, 1)

/*
 * Wakeup macros to be used to report events to the targets.
 */
#define wake_up_poll(x, m)				\
	__wake_up(x, TASK_NORMAL, 1, (void *) (m))
#define wake_up_locked_poll(x, m)				\
	__wake_up_locked_key((x), TASK_NORMAL, (void *) (m))
#define wake_up_interruptible_poll(x, m)			\
	__wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m))
#define wake_up_interruptible_sync_poll(x, m)				\
	__wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m))

#define __wait_event(wq, condition) 					\
do {									\
	DEFINE_WAIT(__wait);						\
									\
	for (;;) {							\
		prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE);	\
		if (condition)						\
			break;						\
		schedule();						\
	}								\
	finish_wait(&wq, &__wait);					\
} while (0)

/**
 * wait_event - sleep until a condition gets true
 * @wq: the waitqueue to wait on
 * @condition: a C expression for the event to wait for
 *
 * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 * @condition evaluates to true. The @condition is checked each time
 * the waitqueue @wq is woken up.
 *
 * wake_up() has to be called after changing any variable that could
 * change the result of the wait condition.
 */
#define wait_event(wq, condition) 					\
do {									\
	if (condition)	 						\
		break;							\
	__wait_event(wq, condition);					\
} while (0)

#define __wait_event_timeout(wq, condition, ret)			\
do {									\
	DEFINE_WAIT(__wait);						\
									\
	for (;;) {							\
		prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE);	\
		if (condition)						\
			break;						\
		ret = schedule_timeout(ret);				\
		if (!ret)						\
			break;						\
	}								\
	finish_wait(&wq, &__wait);					\
} while (0)

/**
 * wait_event_timeout - sleep until a condition gets true or a timeout elapses
 * @wq: the waitqueue to wait on
 * @condition: a C expression for the event to wait for
 * @timeout: timeout, in jiffies
 *
 * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
 * @condition evaluates to true. The @condition is checked each time
 * the waitqueue @wq is woken up.
 *
 * wake_up() has to be called after changing any variable that could
 * change the result of the wait condition.
 *
 * The function returns 0 if the @timeout elapsed, and the remaining
 * jiffies if the condition evaluated to true before the timeout elapsed.
 */
#define wait_event_timeout(wq, condition, timeout)			\
({									\
	long __ret = timeout;						\
	if (!(condition)) 						\
		__wait_event_timeout(wq, condition, __ret);		\
	__ret;								\
})

#define __wait_event_interruptible(wq, condition, ret)			\
do {									\
	DEFINE_WAIT(__wait);						\
									\
	for (;;) {							\
		prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);	\
		if (condition)						\
			break;						\
		if (!signal_pending(current)) {				\
			schedule();					\
			continue;					\
		}							\
		ret = -ERESTARTSYS;					\
		break;							\
	}								\
	finish_wait(&wq, &__wait);					\
} while (0)

/**
 * wait_event_interruptible - sleep until a condition gets true
 * @wq: the waitqueue to wait on
 * @condition: a C expression for the event to wait for
 *
 * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 * @condition evaluates to true or a signal is received.
 * The @condition is checked each time the waitqueue @wq is woken up.
 *
 * wake_up() has to be called after changing any variable that could
 * change the result of the wait condition.
 *
 * The function will return -ERESTARTSYS if it was interrupted by a
 * signal and 0 if @condition evaluated to true.
 */
#define wait_event_interruptible(wq, condition)				\
({									\
	int __ret = 0;							\
	if (!(condition))						\
		__wait_event_interruptible(wq, condition, __ret);	\
	__ret;								\
})

#define __wait_event_interruptible_timeout(wq, condition, ret)		\
do {									\
	DEFINE_WAIT(__wait);						\
									\
	for (;;) {							\
		prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE);	\
		if (condition)						\
			break;						\
		if (!signal_pending(current)) {				\
			ret = schedule_timeout(ret);			\
			if (!ret)					\
				break;					\
			continue;					\
		}							\
		ret = -ERESTARTSYS;					\
		break;							\
	}								\
	finish_wait(&wq, &__wait);					\
} while (0)

/**
 * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
 * @wq: the waitqueue to wait on
 * @condition: a C expression for the event to wait for
 * @timeout: timeout, in jiffies
 *
 * The process is put to sleep (TASK_INTERRUPTIBLE) until the
 * @condition evaluates to true or a signal is received.
 * The @condition is checked each time the waitqueue @wq is woken up.
 *
 * wake_up() has to be called after changing any variable that could
 * change the result of the wait condition.
 *
 * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
 * was interrupted by a signal, and the remaining jiffies otherwise
 * if the condition evaluated to true before the timeout elapsed.
 */
#define wait_event_interruptible_timeout(wq, condition, timeout)	\
({									\
	long __ret = timeout;						\
	if (!(condition))						\
		__wait_event_interruptible_timeout(wq, condition, __ret); \
	__ret;								\
})

#define __wait_event_interruptible_exclusive(wq, condition, ret)	\
do {									\
	DEFINE_WAIT(__wait);						\
									\
	for (;;) {							\
		prepare_to_wait_exclusive(&wq, &__wait,			\
					TASK_INTERRUPTIBLE);		\
		if (condition) {					\
			finish_wait(&wq, &__wait);			\
			break;						\
		}							\
		if (!signal_pending(current)) {				\
			schedule();					\
			continue;					\
		}							\
		ret = -ERESTARTSYS;					\
		abort_exclusive_wait(&wq, &__wait, 			\
				TASK_INTERRUPTIBLE, NULL);		\
		break;							\
	}								\
} while (0)

#define wait_event_interruptible_exclusive(wq, condition)		\
({									\
	int __ret = 0;							\
	if (!(condition))						\
		__wait_event_interruptible_exclusive(wq, condition, __ret);\
	__ret;								\
})

#define __wait_event_killable(wq, condition, ret)			\
do {									\
	DEFINE_WAIT(__wait);						\
									\
	for (;;) {							\
		prepare_to_wait(&wq, &__wait, TASK_KILLABLE);		\
		if (condition)						\
			break;						\
		if (!fatal_signal_pending(current)) {			\
			schedule();					\
			continue;					\
		}							\
		ret = -ERESTARTSYS;					\
		break;							\
	}								\
	finish_wait(&wq, &__wait);					\
} while (0)

/**
 * wait_event_killable - sleep until a condition gets true
 * @wq: the waitqueue to wait on
 * @condition: a C expression for the event to wait for
 *
 * The process is put to sleep (TASK_KILLABLE) until the
 * @condition evaluates to true or a signal is received.
 * The @condition is checked each time the waitqueue @wq is woken up.
 *
 * wake_up() has to be called after changing any variable that could
 * change the result of the wait condition.
 *
 * The function will return -ERESTARTSYS if it was interrupted by a
 * signal and 0 if @condition evaluated to true.
 */
#define wait_event_killable(wq, condition)				\
({									\
	int __ret = 0;							\
	if (!(condition))						\
		__wait_event_killable(wq, condition, __ret);		\
	__ret;								\
})

/*
 * Must be called with the spinlock in the wait_queue_head_t held.
 */
static inline void add_wait_queue_exclusive_locked(wait_queue_head_t *q,
						   wait_queue_t * wait)
{
	wait->flags |= WQ_FLAG_EXCLUSIVE;
	__add_wait_queue_tail(q,  wait);
}

/*
 * Must be called with the spinlock in the wait_queue_head_t held.
 */
static inline void remove_wait_queue_locked(wait_queue_head_t *q,
					    wait_queue_t * wait)
{
	__remove_wait_queue(q,  wait);
}

/*
 * These are the old interfaces to sleep waiting for an event.
 * They are racy.  DO NOT use them, use the wait_event* interfaces above.
 * We plan to remove these interfaces.
 */
extern void sleep_on(wait_queue_head_t *q);
extern long sleep_on_timeout(wait_queue_head_t *q,
				      signed long timeout);
extern void interruptible_sleep_on(wait_queue_head_t *q);
extern long interruptible_sleep_on_timeout(wait_queue_head_t *q,
					   signed long timeout);

/*
 * Waitqueues which are removed from the waitqueue_head at wakeup time
 */
void prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state);
void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state);
void finish_wait(wait_queue_head_t *q, wait_queue_t *wait);
void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait,
			unsigned int mode, void *key);
int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key);

#define DEFINE_WAIT(name)						\
	wait_queue_t name = {						\
		.private	= current,				\
		.func		= autoremove_wake_function,		\
		.task_list	= LIST_HEAD_INIT((name).task_list),	\
	}

#define DEFINE_WAIT_BIT(name, word, bit)				\
	struct wait_bit_queue name = {					\
		.key = __WAIT_BIT_KEY_INITIALIZER(word, bit),		\
		.wait	= {						\
			.private	= current,			\
			.func		= wake_bit_function,		\
			.task_list	=				\
				LIST_HEAD_INIT((name).wait.task_list),	\
		},							\
	}

#define init_wait(wait)							\
	do {								\
		(wait)->private = current;				\
		(wait)->func = autoremove_wake_function;		\
		INIT_LIST_HEAD(&(wait)->task_list);			\
	} while (0)

/**
 * wait_on_bit - wait for a bit to be cleared
 * @word: the word being waited on, a kernel virtual address
 * @bit: the bit of the word being waited on
 * @action: the function used to sleep, which may take special actions
 * @mode: the task state to sleep in
 *
 * There is a standard hashed waitqueue table for generic use. This
 * is the part of the hashtable's accessor API that waits on a bit.
 * For instance, if one were to have waiters on a bitflag, one would
 * call wait_on_bit() in threads waiting for the bit to clear.
 * One uses wait_on_bit() where one is waiting for the bit to clear,
 * but has no intention of setting it.
 */
static inline int wait_on_bit(void *word, int bit,
				int (*action)(void *), unsigned mode)
{
	if (!test_bit(bit, word))
		return 0;
	return out_of_line_wait_on_bit(word, bit, action, mode);
}

/**
 * wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
 * @word: the word being waited on, a kernel virtual address
 * @bit: the bit of the word being waited on
 * @action: the function used to sleep, which may take special actions
 * @mode: the task state to sleep in
 *
 * There is a standard hashed waitqueue table for generic use. This
 * is the part of the hashtable's accessor API that waits on a bit
 * when one intends to set it, for instance, trying to lock bitflags.
 * For instance, if one were to have waiters trying to set bitflag
 * and waiting for it to clear before setting it, one would call
 * wait_on_bit() in threads waiting to be able to set the bit.
 * One uses wait_on_bit_lock() where one is waiting for the bit to
 * clear with the intention of setting it, and when done, clearing it.
 */
static inline int wait_on_bit_lock(void *word, int bit,
				int (*action)(void *), unsigned mode)
{
	if (!test_and_set_bit(bit, word))
		return 0;
	return out_of_line_wait_on_bit_lock(word, bit, action, mode);
}
	
#endif /* __KERNEL__ */

#endif
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_WAIT_H
	2	#define _LINUX_WAIT_H
	3
	4	#define WNOHANG 0x00000001
	5	#define WUNTRACED 0x00000002
	6	#define WSTOPPED WUNTRACED
	7	#define WEXITED 0x00000004
	8	#define WCONTINUED 0x00000008
	9	#define WNOWAIT 0x01000000 /* Don't reap, just poll status. */
	10
	11	#define __WNOTHREAD 0x20000000 /* Don't wait on children of other threads in this group */
	12	#define __WALL 0x40000000 /* Wait on all children, regardless of type */
	13	#define __WCLONE 0x80000000 /* Wait only on non-SIGCHLD children */
	14
	15	/* First argument to waitid: */
	16	#define P_ALL 0
	17	#define P_PID 1
	18	#define P_PGID 2
	19
	20	#ifdef __KERNEL__
	21
1da177e4 LT	22	#include <linux/list.h>
	23	#include <linux/stddef.h>
	24	#include <linux/spinlock.h>
	25	#include <asm/system.h>
	26	#include <asm/current.h>
	27
	28	typedef struct __wait_queue wait_queue_t;
	29	typedef int (wait_queue_func_t)(wait_queue_t wait, unsigned mode, int sync, void *key);
	30	int default_wake_function(wait_queue_t wait, unsigned mode, int sync, void key);
	31
	32	struct __wait_queue {
	33	unsigned int flags;
	34	#define WQ_FLAG_EXCLUSIVE 0x01
c43dc2fd	35	void *private;
1da177e4 LT	36	wait_queue_func_t func;
	37	struct list_head task_list;
	38	};
	39
	40	struct wait_bit_key {
	41	void *flags;
	42	int bit_nr;
	43	};
	44
	45	struct wait_bit_queue {
	46	struct wait_bit_key key;
	47	wait_queue_t wait;
	48	};
	49
	50	struct __wait_queue_head {
	51	spinlock_t lock;
	52	struct list_head task_list;
	53	};
	54	typedef struct __wait_queue_head wait_queue_head_t;
	55
8c65b4a6	56	struct task_struct;
1da177e4 LT	57
	58	/*
	59	* Macros for declaration and initialisaton of the datatypes
	60	*/
	61
	62	#define __WAITQUEUE_INITIALIZER(name, tsk) { \
c43dc2fd	63	.private = tsk, \
1da177e4 LT	64	.func = default_wake_function, \
	65	.task_list = { NULL, NULL } }
	66
	67	#define DECLARE_WAITQUEUE(name, tsk) \
	68	wait_queue_t name = __WAITQUEUE_INITIALIZER(name, tsk)
	69
	70	#define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \
e4d91918	71	.lock = __SPIN_LOCK_UNLOCKED(name.lock), \
1da177e4 LT	72	.task_list = { &(name).task_list, &(name).task_list } }
	73
	74	#define DECLARE_WAIT_QUEUE_HEAD(name) \
	75	wait_queue_head_t name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
	76
	77	#define __WAIT_BIT_KEY_INITIALIZER(word, bit) \
	78	{ .flags = word, .bit_nr = bit, }
	79
21d71f51	80	extern void init_waitqueue_head(wait_queue_head_t *q);
1da177e4	81
7259f0d0 PZ	82	#ifdef CONFIG_LOCKDEP
	83	# define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
	84	({ init_waitqueue_head(&name); name; })
	85	# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
	86	wait_queue_head_t name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
	87	#else
	88	# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
	89	#endif
	90
1da177e4 LT	91	static inline void init_waitqueue_entry(wait_queue_t q, struct task_struct p)
	92	{
	93	q->flags = 0;
c43dc2fd	94	q->private = p;
1da177e4 LT	95	q->func = default_wake_function;
	96	}
	97
	98	static inline void init_waitqueue_func_entry(wait_queue_t *q,
	99	wait_queue_func_t func)
	100	{
	101	q->flags = 0;
c43dc2fd	102	q->private = NULL;
1da177e4 LT	103	q->func = func;
	104	}
	105
	106	static inline int waitqueue_active(wait_queue_head_t *q)
	107	{
	108	return !list_empty(&q->task_list);
	109	}
	110
b3c97528 HH	111	extern void add_wait_queue(wait_queue_head_t q, wait_queue_t wait);
	112	extern void add_wait_queue_exclusive(wait_queue_head_t q, wait_queue_t wait);
	113	extern void remove_wait_queue(wait_queue_head_t q, wait_queue_t wait);
1da177e4 LT	114
	115	static inline void __add_wait_queue(wait_queue_head_t head, wait_queue_t new)
	116	{
	117	list_add(&new->task_list, &head->task_list);
	118	}
	119
	120	/*
	121	* Used for wake-one threads:
	122	*/
	123	static inline void __add_wait_queue_tail(wait_queue_head_t *head,
	124	wait_queue_t *new)
	125	{
	126	list_add_tail(&new->task_list, &head->task_list);
	127	}
	128
	129	static inline void __remove_wait_queue(wait_queue_head_t *head,
	130	wait_queue_t *old)
	131	{
	132	list_del(&old->task_list);
	133	}
	134
777c6c5f JW	135	void __wake_up_common(wait_queue_head_t *q, unsigned int mode,
777c6c5f JW	136	int nr_exclusive, int sync, void *key);
b3c97528	137	void __wake_up(wait_queue_head_t q, unsigned int mode, int nr, void key);
4ede816a DL	138	void __wake_up_locked_key(wait_queue_head_t q, unsigned int mode, void key);
	139	void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr,
	140	void *key);
	141	void __wake_up_locked(wait_queue_head_t *q, unsigned int mode);
	142	void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr);
b3c97528 HH	143	void __wake_up_bit(wait_queue_head_t , void , int);
	144	int __wait_on_bit(wait_queue_head_t , struct wait_bit_queue , int ()(void ), unsigned);
	145	int __wait_on_bit_lock(wait_queue_head_t , struct wait_bit_queue , int ()(void ), unsigned);
	146	void wake_up_bit(void *, int);
	147	int out_of_line_wait_on_bit(void , int, int ()(void *), unsigned);
	148	int out_of_line_wait_on_bit_lock(void , int, int ()(void *), unsigned);
	149	wait_queue_head_t bit_waitqueue(void , int);
1da177e4	150
e64d66c8 MW	151	#define wake_up(x) __wake_up(x, TASK_NORMAL, 1, NULL)
	152	#define wake_up_nr(x, nr) __wake_up(x, TASK_NORMAL, nr, NULL)
	153	#define wake_up_all(x) __wake_up(x, TASK_NORMAL, 0, NULL)
	154	#define wake_up_locked(x) __wake_up_locked((x), TASK_NORMAL)
	155
1da177e4 LT	156	#define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
	157	#define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
	158	#define wake_up_interruptible_all(x) __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
e64d66c8	159	#define wake_up_interruptible_sync(x) __wake_up_sync((x), TASK_INTERRUPTIBLE, 1)
1da177e4	160
0ccf831c	161	/*
c0da3775	162	* Wakeup macros to be used to report events to the targets.
0ccf831c	163	*/
c0da3775 DL	164	#define wake_up_poll(x, m) \
	165	__wake_up(x, TASK_NORMAL, 1, (void *) (m))
	166	#define wake_up_locked_poll(x, m) \
	167	__wake_up_locked_key((x), TASK_NORMAL, (void *) (m))
	168	#define wake_up_interruptible_poll(x, m) \
	169	__wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m))
	170	#define wake_up_interruptible_sync_poll(x, m) \
	171	__wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m))
0ccf831c	172
1da177e4 LT	173	#define __wait_event(wq, condition) \
	174	do { \
	175	DEFINE_WAIT(__wait); \
	176	\
	177	for (;;) { \
	178	prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
	179	if (condition) \
	180	break; \
	181	schedule(); \
	182	} \
	183	finish_wait(&wq, &__wait); \
	184	} while (0)
	185
	186	/**
	187	* wait_event - sleep until a condition gets true
	188	* @wq: the waitqueue to wait on
	189	* @condition: a C expression for the event to wait for
	190	*
	191	* The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
	192	* @condition evaluates to true. The @condition is checked each time
	193	* the waitqueue @wq is woken up.
	194	*
	195	* wake_up() has to be called after changing any variable that could
	196	* change the result of the wait condition.
	197	*/
	198	#define wait_event(wq, condition) \
	199	do { \
	200	if (condition) \
	201	break; \
	202	__wait_event(wq, condition); \
	203	} while (0)
	204
	205	#define __wait_event_timeout(wq, condition, ret) \
	206	do { \
	207	DEFINE_WAIT(__wait); \
	208	\
	209	for (;;) { \
	210	prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
	211	if (condition) \
	212	break; \
	213	ret = schedule_timeout(ret); \
	214	if (!ret) \
	215	break; \
	216	} \
	217	finish_wait(&wq, &__wait); \
	218	} while (0)
	219
	220	/**
	221	* wait_event_timeout - sleep until a condition gets true or a timeout elapses
	222	* @wq: the waitqueue to wait on
	223	* @condition: a C expression for the event to wait for
	224	* @timeout: timeout, in jiffies
	225	*
	226	* The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
	227	* @condition evaluates to true. The @condition is checked each time
	228	* the waitqueue @wq is woken up.
	229	*
	230	* wake_up() has to be called after changing any variable that could
	231	* change the result of the wait condition.
	232	*
	233	* The function returns 0 if the @timeout elapsed, and the remaining
	234	* jiffies if the condition evaluated to true before the timeout elapsed.
	235	*/
	236	#define wait_event_timeout(wq, condition, timeout) \
237	({ \
238	long __ret = timeout; \
239	if (!(condition)) \
240	__wait_event_timeout(wq, condition, __ret); \
241	__ret; \
242	})
243
244	#define __wait_event_interruptible(wq, condition, ret) \
245	do { \
246	DEFINE_WAIT(__wait); \
247	\
248	for (;;) { \
249	prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
250	if (condition) \
251	break; \
252	if (!signal_pending(current)) { \
253	schedule(); \
254	continue; \
255	} \
256	ret = -ERESTARTSYS; \
257	break; \
258	} \
259	finish_wait(&wq, &__wait); \
260	} while (0)
261
262	/**
263	* wait_event_interruptible - sleep until a condition gets true
264	* @wq: the waitqueue to wait on
265	* @condition: a C expression for the event to wait for
266	*
267	* The process is put to sleep (TASK_INTERRUPTIBLE) until the
268	* @condition evaluates to true or a signal is received.
269	* The @condition is checked each time the waitqueue @wq is woken up.
270	*
271	* wake_up() has to be called after changing any variable that could
272	* change the result of the wait condition.
273	*
274	* The function will return -ERESTARTSYS if it was interrupted by a
275	* signal and 0 if @condition evaluated to true.
276	*/
277	#define wait_event_interruptible(wq, condition) \
278	({ \
279	int __ret = 0; \
280	if (!(condition)) \
281	__wait_event_interruptible(wq, condition, __ret); \
282	__ret; \
283	})
284
285	#define __wait_event_interruptible_timeout(wq, condition, ret) \
286	do { \
287	DEFINE_WAIT(__wait); \
288	\
289	for (;;) { \
290	prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
291	if (condition) \
292	break; \
293	if (!signal_pending(current)) { \
294	ret = schedule_timeout(ret); \
295	if (!ret) \
296	break; \
297	continue; \
298	} \
299	ret = -ERESTARTSYS; \
300	break; \
301	} \
302	finish_wait(&wq, &__wait); \
303	} while (0)
304
305	/**
306	* wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
307	* @wq: the waitqueue to wait on
308	* @condition: a C expression for the event to wait for
309	* @timeout: timeout, in jiffies
310	*
311	* The process is put to sleep (TASK_INTERRUPTIBLE) until the
312	* @condition evaluates to true or a signal is received.
313	* The @condition is checked each time the waitqueue @wq is woken up.
314	*
315	* wake_up() has to be called after changing any variable that could
316	* change the result of the wait condition.
317	*
318	* The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
319	* was interrupted by a signal, and the remaining jiffies otherwise
320	* if the condition evaluated to true before the timeout elapsed.
321	*/
322	#define wait_event_interruptible_timeout(wq, condition, timeout) \
323	({ \
324	long __ret = timeout; \
325	if (!(condition)) \
326	__wait_event_interruptible_timeout(wq, condition, __ret); \
327	__ret; \
328	})
329
330	#define __wait_event_interruptible_exclusive(wq, condition, ret) \
331	do { \
332	DEFINE_WAIT(__wait); \
333	\
334	for (;;) { \
335	prepare_to_wait_exclusive(&wq, &__wait, \
336	TASK_INTERRUPTIBLE); \
777c6c5f JW	337	if (condition) { \
777c6c5f JW	338	finish_wait(&wq, &__wait); \
1da177e4	339	break; \
777c6c5f	340	} \
1da177e4 LT	341	if (!signal_pending(current)) { \
	342	schedule(); \
	343	continue; \
	344	} \
	345	ret = -ERESTARTSYS; \
777c6c5f JW	346	abort_exclusive_wait(&wq, &__wait, \
777c6c5f JW	347	TASK_INTERRUPTIBLE, NULL); \
1da177e4 LT	348	break; \
1da177e4 LT	349	} \
1da177e4 LT	350	} while (0)
	351
	352	#define wait_event_interruptible_exclusive(wq, condition) \
	353	({ \
	354	int __ret = 0; \
	355	if (!(condition)) \
	356	__wait_event_interruptible_exclusive(wq, condition, __ret);\
	357	__ret; \
	358	})
	359
1411d5a7 MW	360	#define __wait_event_killable(wq, condition, ret) \
	361	do { \
	362	DEFINE_WAIT(__wait); \
	363	\
	364	for (;;) { \
	365	prepare_to_wait(&wq, &__wait, TASK_KILLABLE); \
	366	if (condition) \
	367	break; \
	368	if (!fatal_signal_pending(current)) { \
	369	schedule(); \
	370	continue; \
	371	} \
	372	ret = -ERESTARTSYS; \
	373	break; \
	374	} \
	375	finish_wait(&wq, &__wait); \
	376	} while (0)
	377
	378	/**
	379	* wait_event_killable - sleep until a condition gets true
	380	* @wq: the waitqueue to wait on
	381	* @condition: a C expression for the event to wait for
	382	*
	383	* The process is put to sleep (TASK_KILLABLE) until the
	384	* @condition evaluates to true or a signal is received.
	385	* The @condition is checked each time the waitqueue @wq is woken up.
	386	*
	387	* wake_up() has to be called after changing any variable that could
	388	* change the result of the wait condition.
	389	*
	390	* The function will return -ERESTARTSYS if it was interrupted by a
	391	* signal and 0 if @condition evaluated to true.
	392	*/
	393	#define wait_event_killable(wq, condition) \
	394	({ \
	395	int __ret = 0; \
	396	if (!(condition)) \
	397	__wait_event_killable(wq, condition, __ret); \
	398	__ret; \
	399	})
	400
1da177e4 LT	401	/*
	402	* Must be called with the spinlock in the wait_queue_head_t held.
	403	*/
	404	static inline void add_wait_queue_exclusive_locked(wait_queue_head_t *q,
	405	wait_queue_t * wait)
	406	{
	407	wait->flags \|= WQ_FLAG_EXCLUSIVE;
	408	__add_wait_queue_tail(q, wait);
	409	}
	410
	411	/*
	412	* Must be called with the spinlock in the wait_queue_head_t held.
	413	*/
	414	static inline void remove_wait_queue_locked(wait_queue_head_t *q,
	415	wait_queue_t * wait)
	416	{
	417	__remove_wait_queue(q, wait);
	418	}
	419
	420	/*
	421	* These are the old interfaces to sleep waiting for an event.
0fec171c IM	422	* They are racy. DO NOT use them, use the wait_event* interfaces above.
0fec171c IM	423	* We plan to remove these interfaces.
1da177e4	424	*/
0fec171c IM	425	extern void sleep_on(wait_queue_head_t *q);
	426	extern long sleep_on_timeout(wait_queue_head_t *q,
	427	signed long timeout);
	428	extern void interruptible_sleep_on(wait_queue_head_t *q);
	429	extern long interruptible_sleep_on_timeout(wait_queue_head_t *q,
	430	signed long timeout);
1da177e4 LT	431
	432	/*
	433	* Waitqueues which are removed from the waitqueue_head at wakeup time
	434	*/
b3c97528 HH	435	void prepare_to_wait(wait_queue_head_t q, wait_queue_t wait, int state);
	436	void prepare_to_wait_exclusive(wait_queue_head_t q, wait_queue_t wait, int state);
	437	void finish_wait(wait_queue_head_t q, wait_queue_t wait);
777c6c5f JW	438	void abort_exclusive_wait(wait_queue_head_t q, wait_queue_t wait,
777c6c5f JW	439	unsigned int mode, void *key);
1da177e4 LT	440	int autoremove_wake_function(wait_queue_t wait, unsigned mode, int sync, void key);
	441	int wake_bit_function(wait_queue_t wait, unsigned mode, int sync, void key);
	442
	443	#define DEFINE_WAIT(name) \
	444	wait_queue_t name = { \
c43dc2fd	445	.private = current, \
1da177e4	446	.func = autoremove_wake_function, \
7e43c84e	447	.task_list = LIST_HEAD_INIT((name).task_list), \
1da177e4 LT	448	}
	449
	450	#define DEFINE_WAIT_BIT(name, word, bit) \
	451	struct wait_bit_queue name = { \
	452	.key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \
	453	.wait = { \
c43dc2fd	454	.private = current, \
1da177e4 LT	455	.func = wake_bit_function, \
	456	.task_list = \
	457	LIST_HEAD_INIT((name).wait.task_list), \
	458	}, \
	459	}
	460
	461	#define init_wait(wait) \
	462	do { \
c43dc2fd	463	(wait)->private = current; \
1da177e4 LT	464	(wait)->func = autoremove_wake_function; \
	465	INIT_LIST_HEAD(&(wait)->task_list); \
	466	} while (0)
	467
	468	/**
	469	* wait_on_bit - wait for a bit to be cleared
	470	* @word: the word being waited on, a kernel virtual address
	471	* @bit: the bit of the word being waited on
	472	* @action: the function used to sleep, which may take special actions
	473	* @mode: the task state to sleep in
	474	*
	475	* There is a standard hashed waitqueue table for generic use. This
	476	* is the part of the hashtable's accessor API that waits on a bit.
	477	* For instance, if one were to have waiters on a bitflag, one would
	478	* call wait_on_bit() in threads waiting for the bit to clear.
	479	* One uses wait_on_bit() where one is waiting for the bit to clear,
	480	* but has no intention of setting it.
	481	*/
	482	static inline int wait_on_bit(void *word, int bit,
	483	int (action)(void ), unsigned mode)
	484	{
	485	if (!test_bit(bit, word))
	486	return 0;
	487	return out_of_line_wait_on_bit(word, bit, action, mode);
	488	}
	489
	490	/**
	491	* wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
	492	* @word: the word being waited on, a kernel virtual address
	493	* @bit: the bit of the word being waited on
	494	* @action: the function used to sleep, which may take special actions
	495	* @mode: the task state to sleep in
	496	*
	497	* There is a standard hashed waitqueue table for generic use. This
	498	* is the part of the hashtable's accessor API that waits on a bit
	499	* when one intends to set it, for instance, trying to lock bitflags.
	500	* For instance, if one were to have waiters trying to set bitflag
	501	* and waiting for it to clear before setting it, one would call
	502	* wait_on_bit() in threads waiting to be able to set the bit.
	503	* One uses wait_on_bit_lock() where one is waiting for the bit to
	504	* clear with the intention of setting it, and when done, clearing it.
	505	*/
	506	static inline int wait_on_bit_lock(void *word, int bit,
	507	int (action)(void ), unsigned mode)
	508	{
	509	if (!test_and_set_bit(bit, word))
	510	return 0;
	511	return out_of_line_wait_on_bit_lock(word, bit, action, mode);
	512	}
	513
	514	#endif /* __KERNEL__ */
	515
	516	#endif