include/linux/wait.h - arm/linux-arm64-legacy - Git at Google

 #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, }

 static inline void init_waitqueue_head(wait_queue_head_t *q)
 {
 	spin_lock_init(&q->lock);
 	INIT_LIST_HEAD(&q->task_list);
 }

 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);
 }

 /*
  * Used to distinguish between sync and async io wait context:
  * sync i/o typically specifies a NULL wait queue entry or a wait
  * queue entry bound to a task (current task) to wake up.
  * aio specifies a wait queue entry with an async notification
  * callback routine, not associated with any task.
  */
 #define is_sync_wait(wait)	(!(wait) || ((wait)->private))

 extern void FASTCALL(add_wait_queue(wait_queue_head_t *q, wait_queue_t * wait));
 extern void FASTCALL(add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t * wait));
 extern void FASTCALL(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 FASTCALL(__wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key));
 extern void FASTCALL(__wake_up_locked(wait_queue_head_t *q, unsigned int mode));
 extern void FASTCALL(__wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr));
 void FASTCALL(__wake_up_bit(wait_queue_head_t *, void *, int));
 int FASTCALL(__wait_on_bit(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned));
 int FASTCALL(__wait_on_bit_lock(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned));
 void FASTCALL(wake_up_bit(void *, int));
 int FASTCALL(out_of_line_wait_on_bit(void *, int, int (*)(void *), unsigned));
 int FASTCALL(out_of_line_wait_on_bit_lock(void *, int, int (*)(void *), unsigned));
 wait_queue_head_t *FASTCALL(bit_waitqueue(void *, int));

 #define wake_up(x)			__wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 1, NULL)
 #define wake_up_nr(x, nr)		__wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, nr, NULL)
 #define wake_up_all(x)			__wake_up(x, TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE, 0, NULL)
 #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_locked(x)		__wake_up_locked((x), TASK_UNINTERRUPTIBLE | TASK_INTERRUPTIBLE)
 #define wake_up_interruptible_sync(x)   __wake_up_sync((x),TASK_INTERRUPTIBLE, 1)

 #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)						\
 			break;						\
 		if (!signal_pending(current)) {				\
 			schedule();					\
 			continue;					\
 		}							\
 		ret = -ERESTARTSYS;					\
 		break;							\
 	}								\
 	finish_wait(&wq, &__wait);					\
 } while (0)

 #define wait_event_interruptible_exclusive(wq, condition)		\
 ({									\
 	int __ret = 0;							\
 	if (!(condition))						\
 		__wait_event_interruptible_exclusive(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 during 2.7.
  */
 extern void FASTCALL(sleep_on(wait_queue_head_t *q));
 extern long FASTCALL(sleep_on_timeout(wait_queue_head_t *q,
 				      signed long timeout));
 extern void FASTCALL(interruptible_sleep_on(wait_queue_head_t *q));
 extern long FASTCALL(interruptible_sleep_on_timeout(wait_queue_head_t *q,
 						    signed long timeout));

 /*
  * Waitqueues which are removed from the waitqueue_head at wakeup time
  */
 void FASTCALL(prepare_to_wait(wait_queue_head_t *q,
 				wait_queue_t *wait, int state));
 void FASTCALL(prepare_to_wait_exclusive(wait_queue_head_t *q,
 				wait_queue_t *wait, int state));
 void FASTCALL(finish_wait(wait_queue_head_t *q, wait_queue_t *wait));
 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
	#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, }

	static inline void init_waitqueue_head(wait_queue_head_t *q)
	{
	spin_lock_init(&q->lock);
	INIT_LIST_HEAD(&q->task_list);
	}

	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);
	}

	/*
	* Used to distinguish between sync and async io wait context:
	* sync i/o typically specifies a NULL wait queue entry or a wait
	* queue entry bound to a task (current task) to wake up.
	* aio specifies a wait queue entry with an async notification
	* callback routine, not associated with any task.
	*/
	#define is_sync_wait(wait) (!(wait) \|\| ((wait)->private))

	extern void FASTCALL(add_wait_queue(wait_queue_head_t q, wait_queue_t wait));
	extern void FASTCALL(add_wait_queue_exclusive(wait_queue_head_t q, wait_queue_t wait));
	extern void FASTCALL(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 FASTCALL(__wake_up(wait_queue_head_t q, unsigned int mode, int nr, void key));
	extern void FASTCALL(__wake_up_locked(wait_queue_head_t *q, unsigned int mode));
	extern void FASTCALL(__wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr));
	void FASTCALL(__wake_up_bit(wait_queue_head_t , void , int));
	int FASTCALL(__wait_on_bit(wait_queue_head_t , struct wait_bit_queue , int ()(void ), unsigned));
	int FASTCALL(__wait_on_bit_lock(wait_queue_head_t , struct wait_bit_queue , int ()(void ), unsigned));
	void FASTCALL(wake_up_bit(void *, int));
	int FASTCALL(out_of_line_wait_on_bit(void , int, int ()(void *), unsigned));
	int FASTCALL(out_of_line_wait_on_bit_lock(void , int, int ()(void *), unsigned));
	wait_queue_head_t FASTCALL(bit_waitqueue(void , int));

	#define wake_up(x) __wake_up(x, TASK_UNINTERRUPTIBLE \| TASK_INTERRUPTIBLE, 1, NULL)
	#define wake_up_nr(x, nr) __wake_up(x, TASK_UNINTERRUPTIBLE \| TASK_INTERRUPTIBLE, nr, NULL)
	#define wake_up_all(x) __wake_up(x, TASK_UNINTERRUPTIBLE \| TASK_INTERRUPTIBLE, 0, NULL)
	#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_locked(x) __wake_up_locked((x), TASK_UNINTERRUPTIBLE \| TASK_INTERRUPTIBLE)
	#define wake_up_interruptible_sync(x) __wake_up_sync((x),TASK_INTERRUPTIBLE, 1)

	#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) \
	break; \
	if (!signal_pending(current)) { \
	schedule(); \
	continue; \
	} \
	ret = -ERESTARTSYS; \
	break; \
	} \
	finish_wait(&wq, &__wait); \
	} while (0)

	#define wait_event_interruptible_exclusive(wq, condition) \
	({ \
	int __ret = 0; \
	if (!(condition)) \
	__wait_event_interruptible_exclusive(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 during 2.7.
	*/
	extern void FASTCALL(sleep_on(wait_queue_head_t *q));
	extern long FASTCALL(sleep_on_timeout(wait_queue_head_t *q,
	signed long timeout));
	extern void FASTCALL(interruptible_sleep_on(wait_queue_head_t *q));
	extern long FASTCALL(interruptible_sleep_on_timeout(wait_queue_head_t *q,
	signed long timeout));

	/*
	* Waitqueues which are removed from the waitqueue_head at wakeup time
	*/
	void FASTCALL(prepare_to_wait(wait_queue_head_t *q,
	wait_queue_t *wait, int state));
	void FASTCALL(prepare_to_wait_exclusive(wait_queue_head_t *q,
	wait_queue_t *wait, int state));
	void FASTCALL(finish_wait(wait_queue_head_t q, wait_queue_t wait));
	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