[linux.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 flags, void *key);
int default_wake_function(wait_queue_t *wait, unsigned mode, int flags, 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, struct lock_class_key *);

#define init_waitqueue_head(q)				\
	do {						\
		static struct lock_class_key __key;	\
							\
		__init_waitqueue_head((q), &__key);	\
	} while (0)

#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(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_FUNC(name, function)				\
	wait_queue_t name = {						\
		.private	= current,				\
		.func		= function,				\
		.task_list	= LIST_HEAD_INIT((name).task_list),	\
	}

#define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)

#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;
7d478721 PZ	29	typedef int (wait_queue_func_t)(wait_queue_t wait, unsigned mode, int flags, void *key);
7d478721 PZ	30	int default_wake_function(wait_queue_t wait, unsigned mode, int flags, void key);
1da177e4 LT	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
2fc39111 PZ	80	extern void __init_waitqueue_head(wait_queue_head_t q, struct lock_class_key );
	81
	82	#define init_waitqueue_head(q) \
	83	do { \
	84	static struct lock_class_key __key; \
	85	\
	86	__init_waitqueue_head((q), &__key); \
	87	} while (0)
1da177e4	88
7259f0d0 PZ	89	#ifdef CONFIG_LOCKDEP
	90	# define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
	91	({ init_waitqueue_head(&name); name; })
	92	# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
	93	wait_queue_head_t name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
	94	#else
	95	# define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
	96	#endif
	97
1da177e4 LT	98	static inline void init_waitqueue_entry(wait_queue_t q, struct task_struct p)
	99	{
	100	q->flags = 0;
c43dc2fd	101	q->private = p;
1da177e4 LT	102	q->func = default_wake_function;
	103	}
	104
	105	static inline void init_waitqueue_func_entry(wait_queue_t *q,
	106	wait_queue_func_t func)
	107	{
	108	q->flags = 0;
c43dc2fd	109	q->private = NULL;
1da177e4 LT	110	q->func = func;
	111	}
	112
	113	static inline int waitqueue_active(wait_queue_head_t *q)
	114	{
	115	return !list_empty(&q->task_list);
	116	}
	117
b3c97528 HH	118	extern void add_wait_queue(wait_queue_head_t q, wait_queue_t wait);
	119	extern void add_wait_queue_exclusive(wait_queue_head_t q, wait_queue_t wait);
	120	extern void remove_wait_queue(wait_queue_head_t q, wait_queue_t wait);
1da177e4 LT	121
	122	static inline void __add_wait_queue(wait_queue_head_t head, wait_queue_t new)
	123	{
	124	list_add(&new->task_list, &head->task_list);
	125	}
	126
	127	/*
	128	* Used for wake-one threads:
	129	*/
	130	static inline void __add_wait_queue_tail(wait_queue_head_t *head,
	131	wait_queue_t *new)
	132	{
	133	list_add_tail(&new->task_list, &head->task_list);
	134	}
	135
	136	static inline void __remove_wait_queue(wait_queue_head_t *head,
	137	wait_queue_t *old)
	138	{
	139	list_del(&old->task_list);
	140	}
	141
b3c97528	142	void __wake_up(wait_queue_head_t q, unsigned int mode, int nr, void key);
4ede816a DL	143	void __wake_up_locked_key(wait_queue_head_t q, unsigned int mode, void key);
	144	void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr,
	145	void *key);
	146	void __wake_up_locked(wait_queue_head_t *q, unsigned int mode);
	147	void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr);
b3c97528 HH	148	void __wake_up_bit(wait_queue_head_t , void , int);
	149	int __wait_on_bit(wait_queue_head_t , struct wait_bit_queue , int ()(void ), unsigned);
	150	int __wait_on_bit_lock(wait_queue_head_t , struct wait_bit_queue , int ()(void ), unsigned);
	151	void wake_up_bit(void *, int);
	152	int out_of_line_wait_on_bit(void , int, int ()(void *), unsigned);
	153	int out_of_line_wait_on_bit_lock(void , int, int ()(void *), unsigned);
	154	wait_queue_head_t bit_waitqueue(void , int);
1da177e4	155
e64d66c8 MW	156	#define wake_up(x) __wake_up(x, TASK_NORMAL, 1, NULL)
	157	#define wake_up_nr(x, nr) __wake_up(x, TASK_NORMAL, nr, NULL)
	158	#define wake_up_all(x) __wake_up(x, TASK_NORMAL, 0, NULL)
	159	#define wake_up_locked(x) __wake_up_locked((x), TASK_NORMAL)
	160
1da177e4 LT	161	#define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
	162	#define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
	163	#define wake_up_interruptible_all(x) __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
e64d66c8	164	#define wake_up_interruptible_sync(x) __wake_up_sync((x), TASK_INTERRUPTIBLE, 1)
1da177e4	165
0ccf831c	166	/*
c0da3775	167	* Wakeup macros to be used to report events to the targets.
0ccf831c	168	*/
c0da3775 DL	169	#define wake_up_poll(x, m) \
	170	__wake_up(x, TASK_NORMAL, 1, (void *) (m))
	171	#define wake_up_locked_poll(x, m) \
	172	__wake_up_locked_key((x), TASK_NORMAL, (void *) (m))
	173	#define wake_up_interruptible_poll(x, m) \
	174	__wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m))
	175	#define wake_up_interruptible_sync_poll(x, m) \
	176	__wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m))
0ccf831c	177
1da177e4 LT	178	#define __wait_event(wq, condition) \
	179	do { \
	180	DEFINE_WAIT(__wait); \
	181	\
	182	for (;;) { \
	183	prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
	184	if (condition) \
	185	break; \
	186	schedule(); \
	187	} \
	188	finish_wait(&wq, &__wait); \
	189	} while (0)
	190
	191	/**
	192	* wait_event - sleep until a condition gets true
	193	* @wq: the waitqueue to wait on
	194	* @condition: a C expression for the event to wait for
	195	*
	196	* The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
	197	* @condition evaluates to true. The @condition is checked each time
	198	* the waitqueue @wq is woken up.
	199	*
	200	* wake_up() has to be called after changing any variable that could
	201	* change the result of the wait condition.
	202	*/
	203	#define wait_event(wq, condition) \
	204	do { \
	205	if (condition) \
	206	break; \
	207	__wait_event(wq, condition); \
	208	} while (0)
	209
	210	#define __wait_event_timeout(wq, condition, ret) \
	211	do { \
	212	DEFINE_WAIT(__wait); \
	213	\
	214	for (;;) { \
	215	prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
	216	if (condition) \
	217	break; \
	218	ret = schedule_timeout(ret); \
	219	if (!ret) \
	220	break; \
	221	} \
	222	finish_wait(&wq, &__wait); \
	223	} while (0)
	224
	225	/**
	226	* wait_event_timeout - sleep until a condition gets true or a timeout elapses
	227	* @wq: the waitqueue to wait on
	228	* @condition: a C expression for the event to wait for
	229	* @timeout: timeout, in jiffies
	230	*
	231	* The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
	232	* @condition evaluates to true. The @condition is checked each time
	233	* the waitqueue @wq is woken up.
	234	*
	235	* wake_up() has to be called after changing any variable that could
	236	* change the result of the wait condition.
	237	*
	238	* The function returns 0 if the @timeout elapsed, and the remaining
	239	* jiffies if the condition evaluated to true before the timeout elapsed.
	240	*/
	241	#define wait_event_timeout(wq, condition, timeout) \
242	({ \
243	long __ret = timeout; \
244	if (!(condition)) \
245	__wait_event_timeout(wq, condition, __ret); \
246	__ret; \
247	})
248
249	#define __wait_event_interruptible(wq, condition, ret) \
250	do { \
251	DEFINE_WAIT(__wait); \
252	\
253	for (;;) { \
254	prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
255	if (condition) \
256	break; \
257	if (!signal_pending(current)) { \
258	schedule(); \
259	continue; \
260	} \
261	ret = -ERESTARTSYS; \
262	break; \
263	} \
264	finish_wait(&wq, &__wait); \
265	} while (0)
266
267	/**
268	* wait_event_interruptible - sleep until a condition gets true
269	* @wq: the waitqueue to wait on
270	* @condition: a C expression for the event to wait for
271	*
272	* The process is put to sleep (TASK_INTERRUPTIBLE) until the
273	* @condition evaluates to true or a signal is received.
274	* The @condition is checked each time the waitqueue @wq is woken up.
275	*
276	* wake_up() has to be called after changing any variable that could
277	* change the result of the wait condition.
278	*
279	* The function will return -ERESTARTSYS if it was interrupted by a
280	* signal and 0 if @condition evaluated to true.
281	*/
282	#define wait_event_interruptible(wq, condition) \
283	({ \
284	int __ret = 0; \
285	if (!(condition)) \
286	__wait_event_interruptible(wq, condition, __ret); \
287	__ret; \
288	})
289
290	#define __wait_event_interruptible_timeout(wq, condition, ret) \
291	do { \
292	DEFINE_WAIT(__wait); \
293	\
294	for (;;) { \
295	prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
296	if (condition) \
297	break; \
298	if (!signal_pending(current)) { \
299	ret = schedule_timeout(ret); \
300	if (!ret) \
301	break; \
302	continue; \
303	} \
304	ret = -ERESTARTSYS; \
305	break; \
306	} \
307	finish_wait(&wq, &__wait); \
308	} while (0)
309
310	/**
311	* wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
312	* @wq: the waitqueue to wait on
313	* @condition: a C expression for the event to wait for
314	* @timeout: timeout, in jiffies
315	*
316	* The process is put to sleep (TASK_INTERRUPTIBLE) until the
317	* @condition evaluates to true or a signal is received.
318	* The @condition is checked each time the waitqueue @wq is woken up.
319	*
320	* wake_up() has to be called after changing any variable that could
321	* change the result of the wait condition.
322	*
323	* The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
324	* was interrupted by a signal, and the remaining jiffies otherwise
325	* if the condition evaluated to true before the timeout elapsed.
326	*/
327	#define wait_event_interruptible_timeout(wq, condition, timeout) \
328	({ \
329	long __ret = timeout; \
330	if (!(condition)) \
331	__wait_event_interruptible_timeout(wq, condition, __ret); \
332	__ret; \
333	})
334
335	#define __wait_event_interruptible_exclusive(wq, condition, ret) \
336	do { \
337	DEFINE_WAIT(__wait); \
338	\
339	for (;;) { \
340	prepare_to_wait_exclusive(&wq, &__wait, \
341	TASK_INTERRUPTIBLE); \
777c6c5f JW	342	if (condition) { \
777c6c5f JW	343	finish_wait(&wq, &__wait); \
1da177e4	344	break; \
777c6c5f	345	} \
1da177e4 LT	346	if (!signal_pending(current)) { \
	347	schedule(); \
	348	continue; \
	349	} \
	350	ret = -ERESTARTSYS; \
777c6c5f JW	351	abort_exclusive_wait(&wq, &__wait, \
777c6c5f JW	352	TASK_INTERRUPTIBLE, NULL); \
1da177e4 LT	353	break; \
1da177e4 LT	354	} \
1da177e4 LT	355	} while (0)
	356
	357	#define wait_event_interruptible_exclusive(wq, condition) \
	358	({ \
	359	int __ret = 0; \
	360	if (!(condition)) \
	361	__wait_event_interruptible_exclusive(wq, condition, __ret);\
	362	__ret; \
	363	})
	364
1411d5a7 MW	365	#define __wait_event_killable(wq, condition, ret) \
	366	do { \
	367	DEFINE_WAIT(__wait); \
	368	\
	369	for (;;) { \
	370	prepare_to_wait(&wq, &__wait, TASK_KILLABLE); \
	371	if (condition) \
	372	break; \
	373	if (!fatal_signal_pending(current)) { \
	374	schedule(); \
	375	continue; \
	376	} \
	377	ret = -ERESTARTSYS; \
	378	break; \
	379	} \
	380	finish_wait(&wq, &__wait); \
	381	} while (0)
	382
	383	/**
	384	* wait_event_killable - sleep until a condition gets true
	385	* @wq: the waitqueue to wait on
	386	* @condition: a C expression for the event to wait for
	387	*
	388	* The process is put to sleep (TASK_KILLABLE) until the
	389	* @condition evaluates to true or a signal is received.
	390	* The @condition is checked each time the waitqueue @wq is woken up.
	391	*
	392	* wake_up() has to be called after changing any variable that could
	393	* change the result of the wait condition.
	394	*
	395	* The function will return -ERESTARTSYS if it was interrupted by a
	396	* signal and 0 if @condition evaluated to true.
	397	*/
	398	#define wait_event_killable(wq, condition) \
	399	({ \
	400	int __ret = 0; \
	401	if (!(condition)) \
	402	__wait_event_killable(wq, condition, __ret); \
	403	__ret; \
	404	})
	405
1da177e4 LT	406	/*
	407	* Must be called with the spinlock in the wait_queue_head_t held.
	408	*/
	409	static inline void add_wait_queue_exclusive_locked(wait_queue_head_t *q,
	410	wait_queue_t * wait)
	411	{
	412	wait->flags \|= WQ_FLAG_EXCLUSIVE;
	413	__add_wait_queue_tail(q, wait);
	414	}
	415
	416	/*
	417	* Must be called with the spinlock in the wait_queue_head_t held.
	418	*/
	419	static inline void remove_wait_queue_locked(wait_queue_head_t *q,
	420	wait_queue_t * wait)
	421	{
	422	__remove_wait_queue(q, wait);
	423	}
	424
	425	/*
	426	* These are the old interfaces to sleep waiting for an event.
0fec171c IM	427	* They are racy. DO NOT use them, use the wait_event* interfaces above.
0fec171c IM	428	* We plan to remove these interfaces.
1da177e4	429	*/
0fec171c IM	430	extern void sleep_on(wait_queue_head_t *q);
	431	extern long sleep_on_timeout(wait_queue_head_t *q,
	432	signed long timeout);
	433	extern void interruptible_sleep_on(wait_queue_head_t *q);
	434	extern long interruptible_sleep_on_timeout(wait_queue_head_t *q,
	435	signed long timeout);
1da177e4 LT	436
	437	/*
	438	* Waitqueues which are removed from the waitqueue_head at wakeup time
	439	*/
b3c97528 HH	440	void prepare_to_wait(wait_queue_head_t q, wait_queue_t wait, int state);
	441	void prepare_to_wait_exclusive(wait_queue_head_t q, wait_queue_t wait, int state);
	442	void finish_wait(wait_queue_head_t q, wait_queue_t wait);
777c6c5f JW	443	void abort_exclusive_wait(wait_queue_head_t q, wait_queue_t wait,
777c6c5f JW	444	unsigned int mode, void *key);
1da177e4 LT	445	int autoremove_wake_function(wait_queue_t wait, unsigned mode, int sync, void key);
	446	int wake_bit_function(wait_queue_t wait, unsigned mode, int sync, void key);
	447
bf368e4e	448	#define DEFINE_WAIT_FUNC(name, function) \
1da177e4	449	wait_queue_t name = { \
c43dc2fd	450	.private = current, \
bf368e4e	451	.func = function, \
7e43c84e	452	.task_list = LIST_HEAD_INIT((name).task_list), \
1da177e4 LT	453	}
1da177e4 LT	454
bf368e4e ED	455	#define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)
bf368e4e ED	456
1da177e4 LT	457	#define DEFINE_WAIT_BIT(name, word, bit) \
	458	struct wait_bit_queue name = { \
	459	.key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \
	460	.wait = { \
c43dc2fd	461	.private = current, \
1da177e4 LT	462	.func = wake_bit_function, \
	463	.task_list = \
	464	LIST_HEAD_INIT((name).wait.task_list), \
	465	}, \
	466	}
	467
	468	#define init_wait(wait) \
	469	do { \
c43dc2fd	470	(wait)->private = current; \
1da177e4 LT	471	(wait)->func = autoremove_wake_function; \
	472	INIT_LIST_HEAD(&(wait)->task_list); \
	473	} while (0)
	474
	475	/**
	476	* wait_on_bit - wait for a bit to be cleared
	477	* @word: the word being waited on, a kernel virtual address
	478	* @bit: the bit of the word being waited on
	479	* @action: the function used to sleep, which may take special actions
	480	* @mode: the task state to sleep in
	481	*
	482	* There is a standard hashed waitqueue table for generic use. This
	483	* is the part of the hashtable's accessor API that waits on a bit.
	484	* For instance, if one were to have waiters on a bitflag, one would
	485	* call wait_on_bit() in threads waiting for the bit to clear.
	486	* One uses wait_on_bit() where one is waiting for the bit to clear,
	487	* but has no intention of setting it.
	488	*/
	489	static inline int wait_on_bit(void *word, int bit,
	490	int (action)(void ), unsigned mode)
	491	{
	492	if (!test_bit(bit, word))
	493	return 0;
	494	return out_of_line_wait_on_bit(word, bit, action, mode);
	495	}
	496
	497	/**
	498	* wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
	499	* @word: the word being waited on, a kernel virtual address
	500	* @bit: the bit of the word being waited on
	501	* @action: the function used to sleep, which may take special actions
	502	* @mode: the task state to sleep in
	503	*
	504	* There is a standard hashed waitqueue table for generic use. This
	505	* is the part of the hashtable's accessor API that waits on a bit
	506	* when one intends to set it, for instance, trying to lock bitflags.
	507	* For instance, if one were to have waiters trying to set bitflag
	508	* and waiting for it to clear before setting it, one would call
	509	* wait_on_bit() in threads waiting to be able to set the bit.
	510	* One uses wait_on_bit_lock() where one is waiting for the bit to
	511	* clear with the intention of setting it, and when done, clearing it.
	512	*/
	513	static inline int wait_on_bit_lock(void *word, int bit,
	514	int (action)(void ), unsigned mode)
	515	{
	516	if (!test_and_set_bit(bit, word))
	517	return 0;
	518	return out_of_line_wait_on_bit_lock(word, bit, action, mode);
	519	}
	520
	521	#endif /* __KERNEL__ */
	522
	523	#endif