#ifndef __LINUX_COMPLETION_H#define __LINUX_COMPLETION_H /* * (C) Copyright 2001 Linus Torvalds * * Atomic wait-for-completion handler data structures. * See kernel/sched.c for details. */ #include <linux/wait.h> /** * struct completion - structure used to maintain state for a "completion" * * This is the opaque structure used to maintain the state for a "completion". * Completions currently use a FIFO to queue threads that have to wait for * the "completion" event. * * See also:  complete(), wait_for_completion() (and friends _timeout, * _interruptible, _interruptible_timeout, and _killable), init_completion(), * and macros DECLARE_COMPLETION(), DECLARE_COMPLETION_ONSTACK(), and * INIT_COMPLETION(). */struct completion {	unsigned int done;	wait_queue_head_t wait;}; #define COMPLETION_INITIALIZER(work) \	{ 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) } #define COMPLETION_INITIALIZER_ONSTACK(work) \	({ init_completion(&work); work; }) /** * DECLARE_COMPLETION: - declare and initialize a completion structure * @work:  identifier for the completion structure * * This macro declares and initializes a completion structure. Generally used * for static declarations. You should use the _ONSTACK variant for automatic * variables. */#define DECLARE_COMPLETION(work) \	struct completion work = COMPLETION_INITIALIZER(work) /* * Lockdep needs to run a non-constant initializer for on-stack * completions - so we use the _ONSTACK() variant for those that * are on the kernel stack: *//** * DECLARE_COMPLETION_ONSTACK: - declare and initialize a completion structure * @work:  identifier for the completion structure * * This macro declares and initializes a completion structure on the kernel * stack. */#ifdef CONFIG_LOCKDEP# define DECLARE_COMPLETION_ONSTACK(work) \	struct completion work = COMPLETION_INITIALIZER_ONSTACK(work)#else# define DECLARE_COMPLETION_ONSTACK(work) DECLARE_COMPLETION(work)#endif /** * init_completion: - Initialize a dynamically allocated completion * @x:  completion structure that is to be initialized * * This inline function will initialize a dynamically created completion * structure. */static inline void init_completion(struct completion *x){	x->done = 0;	init_waitqueue_head(&x->wait);} extern void wait_for_completion(struct completion *);extern int wait_for_completion_interruptible(struct completion *x);extern int wait_for_completion_killable(struct completion *x);extern unsigned long wait_for_completion_timeout(struct completion *x,						   unsigned long timeout);extern unsigned long wait_for_completion_interruptible_timeout(			struct completion *x, unsigned long timeout);extern unsigned long wait_for_completion_killable_timeout(			struct completion *x, unsigned long timeout);extern bool try_wait_for_completion(struct completion *x);extern bool completion_done(struct completion *x); extern void complete(struct completion *);extern void complete_all(struct completion *); /** * INIT_COMPLETION: - reinitialize a completion structure * @x:  completion structure to be reinitialized * * This macro should be used to reinitialize a completion structure so it can * be reused. This is especially important after complete_all() is used. */#define INIT_COMPLETION(x)	((x).done = 0)  #endif