/*
 * workqueue.h --- work queue handling for Linux.
 */

#ifndef _LINUX_WORKQUEUE_H
#define _LINUX_WORKQUEUE_H

#include <linux/timer.h>
#include <linux/linkage.h>
#include <linux/bitops.h>
#include <linux/lockdep.h>
#include <asm/atomic.h>

struct workqueue_struct;

struct work_struct;
typedef void (*work_func_t)(struct work_struct *work);

/*
 * The first word is the work queue pointer and the flags rolled into
 * one
 */
#define work_data_bits(work) ((unsigned long *)(&(work)->data))

struct work_struct {
        atomic_long_t data;
#define WORK_STRUCT_PENDING 0           /* T if work item pending execution */
#define WORK_STRUCT_FLAG_MASK (3UL)
#define WORK_STRUCT_WQ_DATA_MASK (~WORK_STRUCT_FLAG_MASK)
        struct list_head entry;
        work_func_t func;
#ifdef CONFIG_LOCKDEP
        struct lockdep_map lockdep_map;
#endif
};

#define WORK_DATA_INIT()        ATOMIC_LONG_INIT(0)

struct delayed_work {
        struct work_struct work;
        struct timer_list timer;
};

struct execute_work {
        struct work_struct work;
};

#ifdef CONFIG_LOCKDEP
/*
 * NB: because we have to copy the lockdep_map, setting _key
 * here is required, otherwise it could get initialised to the
 * copy of the lockdep_map!
 */
#define __WORK_INIT_LOCKDEP_MAP(n, k) \
        .lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
#else
#define __WORK_INIT_LOCKDEP_MAP(n, k)
#endif

#define __WORK_INITIALIZER(n, f) {                              \
        .data = WORK_DATA_INIT(),                               \
        .entry  = { &(n).entry, &(n).entry },                   \
        .func = (f),                                            \
        __WORK_INIT_LOCKDEP_MAP(#n, &(n))                       \
        }

#define __DELAYED_WORK_INITIALIZER(n, f) {                      \
        .work = __WORK_INITIALIZER((n).work, (f)),              \
        .timer = TIMER_INITIALIZER(NULL, 0, 0),                 \
        }

#define DECLARE_WORK(n, f)                                      \
        struct work_struct n = __WORK_INITIALIZER(n, f)

#define DECLARE_DELAYED_WORK(n, f)                              \
        struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f)

/*
 * initialize a work item's function pointer
 */
#define PREPARE_WORK(_work, _func)                              \
        do {                                                    \
                (_work)->func = (_func);                        \
        } while (0)

#define PREPARE_DELAYED_WORK(_work, _func)                      \
        PREPARE_WORK(&(_work)->work, (_func))

/*
 * initialize all of a work item in one go
 *
 * NOTE! No point in using "atomic_long_set()": useing a direct
 * assignment of the work data initializer allows the compiler
 * to generate better code.
 */
#ifdef CONFIG_LOCKDEP
#define INIT_WORK(_work, _func)                                         \
        do {                                                            \
                static struct lock_class_key __key;                     \
                                                                        \
                (_work)->data = (atomic_long_t) WORK_DATA_INIT();       \
                lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0);\
                INIT_LIST_HEAD(&(_work)->entry);                        \
                PREPARE_WORK((_work), (_func));                         \
        } while (0)
#else
#define INIT_WORK(_work, _func)                                         \
        do {                                                            \
                (_work)->data = (atomic_long_t) WORK_DATA_INIT();       \
                INIT_LIST_HEAD(&(_work)->entry);                        \
                PREPARE_WORK((_work), (_func));                         \
        } while (0)
#endif

#define INIT_DELAYED_WORK(_work, _func)                         \
        do {                                                    \
                INIT_WORK(&(_work)->work, (_func));             \
                init_timer(&(_work)->timer);                    \
        } while (0)

#define INIT_DELAYED_WORK_DEFERRABLE(_work, _func)                      \
        do {                                                    \
                INIT_WORK(&(_work)->work, (_func));             \
                init_timer_deferrable(&(_work)->timer);         \
        } while (0)

/**
 * work_pending - Find out whether a work item is currently pending
 * @work: The work item in question
 */
#define work_pending(work) \
        test_bit(WORK_STRUCT_PENDING, work_data_bits(work))

/**
 * delayed_work_pending - Find out whether a delayable work item is currently
 * pending
 * @work: The work item in question
 */
#define delayed_work_pending(w) \
        work_pending(&(w)->work)

/**
 * work_clear_pending - for internal use only, mark a work item as not pending
 * @work: The work item in question
 */
#define work_clear_pending(work) \
        clear_bit(WORK_STRUCT_PENDING, work_data_bits(work))


extern struct workqueue_struct *
__create_workqueue_key(const char *name, int singlethread,
                       int freezeable, struct lock_class_key *key,
                       const char *lock_name);

#ifdef CONFIG_LOCKDEP
#define __create_workqueue(name, singlethread, freezeable)      \
({                                                              \
        static struct lock_class_key __key;                     \
        const char *__lock_name;                                \
                                                                \
        if (__builtin_constant_p(name))                         \
                __lock_name = (name);                           \
        else                                                    \
                __lock_name = #name;                            \
                                                                \
        __create_workqueue_key((name), (singlethread),          \
                               (freezeable), &__key,            \
                               __lock_name);                    \
})
#else
#define __create_workqueue(name, singlethread, freezeable)      \
        __create_workqueue_key((name), (singlethread), (freezeable), NULL, NULL)
#endif

#define create_workqueue(name) __create_workqueue((name), 0, 0)
#define create_freezeable_workqueue(name) __create_workqueue((name), 1, 1)
#define create_singlethread_workqueue(name) __create_workqueue((name), 1, 0)

extern void destroy_workqueue(struct workqueue_struct *wq);

extern int FASTCALL(queue_work(struct workqueue_struct *wq, struct work_struct *work));
extern int FASTCALL(queue_delayed_work(struct workqueue_struct *wq,
                        struct delayed_work *work, unsigned long delay));
extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
                        struct delayed_work *work, unsigned long delay);

extern void FASTCALL(flush_workqueue(struct workqueue_struct *wq));
extern void flush_scheduled_work(void);

extern int FASTCALL(schedule_work(struct work_struct *work));
extern int FASTCALL(schedule_delayed_work(struct delayed_work *work,
                                        unsigned long delay));
extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,
                                        unsigned long delay);
extern int schedule_on_each_cpu(work_func_t func);
extern int current_is_keventd(void);
extern int keventd_up(void);

extern void init_workqueues(void);
int execute_in_process_context(work_func_t fn, struct execute_work *);

extern int cancel_work_sync(struct work_struct *work);

/*
 * Kill off a pending schedule_delayed_work().  Note that the work callback
 * function may still be running on return from cancel_delayed_work(), unless
 * it returns 1 and the work doesn't re-arm itself. Run flush_workqueue() or
 * cancel_work_sync() to wait on it.
 */
static inline int cancel_delayed_work(struct delayed_work *work)
{
        int ret;

        ret = del_timer_sync(&work->timer);
        if (ret)
                work_clear_pending(&work->work);
        return ret;
}

extern int cancel_delayed_work_sync(struct delayed_work *work);

/* Obsolete. use cancel_delayed_work_sync() */
static inline
void cancel_rearming_delayed_workqueue(struct workqueue_struct *wq,
                                        struct delayed_work *work)
{
        cancel_delayed_work_sync(work);
}

/* Obsolete. use cancel_delayed_work_sync() */
static inline
void cancel_rearming_delayed_work(struct delayed_work *work)
{
        cancel_delayed_work_sync(work);
}

#endif