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/*

 * linux/include/asm-arm/semaphore.h

 */

#ifndef __ASM_ARM_SEMAPHORE_H

#define __ASM_ARM_SEMAPHORE_H

#include <linux/linkage.h>

#include <linux/spinlock.h>

#include <linux/wait.h>

#include <linux/rwsem.h>

#include <asm/atomic.h>

#include <asm/proc/locks.h>

struct semaphore {

        atomic_t count;

        int sleepers;

        wait_queue_head_t wait;

#if WAITQUEUE_DEBUG

        long __magic;

#endif

};

#if WAITQUEUE_DEBUG

# define __SEM_DEBUG_INIT(name) \

                , (long)&(name).__magic

#else

# define __SEM_DEBUG_INIT(name)

#endif

#define __SEMAPHORE_INIT(name,count)                    \

        { ATOMIC_INIT(count), 0,                 \

          __WAIT_QUEUE_HEAD_INITIALIZER((name).wait)    \

          __SEM_DEBUG_INIT(name) }

#define __MUTEX_INITIALIZER(name) \

        __SEMAPHORE_INIT(name,1)

#define __DECLARE_SEMAPHORE_GENERIC(name,count) \

        struct semaphore name = __SEMAPHORE_INIT(name,count)

#define DECLARE_MUTEX(name)             __DECLARE_SEMAPHORE_GENERIC(name,1)

#define DECLARE_MUTEX_LOCKED(name)      __DECLARE_SEMAPHORE_GENERIC(name,0)

static inline void sema_init(struct semaphore *sem, int val)

{

        atomic_set(&sem->count, val);

        sem->sleepers = 0;

        init_waitqueue_head(&sem->wait);

#if WAITQUEUE_DEBUG

        sem->__magic = (long)&sem->__magic;

#endif

}

static inline void init_MUTEX(struct semaphore *sem)

{

        sema_init(sem, 1);

}

static inline void init_MUTEX_LOCKED(struct semaphore *sem)

{

        sema_init(sem, 0);

}

/*

 * special register calling convention

 */

asmlinkage void __down_failed(void);

asmlinkage int  __down_interruptible_failed(void);

asmlinkage int  __down_trylock_failed(void);

asmlinkage void __up_wakeup(void);

extern void __down(struct semaphore * sem);

extern int  __down_interruptible(struct semaphore * sem);

extern int  __down_trylock(struct semaphore * sem);

extern void __up(struct semaphore * sem);

/*

 * This is ugly, but we want the default case to fall through.

 * "__down" is the actual routine that waits...

 */

static inline void down(struct semaphore * sem)

{

#if WAITQUEUE_DEBUG

        CHECK_MAGIC(sem->__magic);

#endif

        __down_op(sem, __down_failed);

}

/*

 * This is ugly, but we want the default case to fall through.

 * "__down_interruptible" is the actual routine that waits...

 */

static inline int down_interruptible (struct semaphore * sem)

{

#if WAITQUEUE_DEBUG

        CHECK_MAGIC(sem->__magic);

#endif

        return __down_op_ret(sem, __down_interruptible_failed);

}

static inline int down_trylock(struct semaphore *sem)

{

#if WAITQUEUE_DEBUG

        CHECK_MAGIC(sem->__magic);

#endif

        return __down_op_ret(sem, __down_trylock_failed);

}

/*

 * Note! This is subtle. We jump to wake people up only if

 * the semaphore was negative (== somebody was waiting on it).

 * The default case (no contention) will result in NO

 * jumps for both down() and up().

 */

static inline void up(struct semaphore * sem)

{

#if WAITQUEUE_DEBUG

        CHECK_MAGIC(sem->__magic);

#endif

        __up_op(sem, __up_wakeup);

}

static inline int sem_getcount(struct semaphore *sem)

{

        return atomic_read(&sem->count);

}

#endif