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#ifndef _M68K_SEMAPHORE_H

#define _M68K_SEMAPHORE_H

#define RW_LOCK_BIAS             0x01000000

#ifndef __ASSEMBLY__

#include <linux/linkage.h>

#include <linux/wait.h>

#include <linux/spinlock.h>

#include <linux/rwsem.h>

#include <asm/system.h>

#include <asm/atomic.h>

/*

 * Interrupt-safe semaphores..

 *

 * (C) Copyright 1996 Linus Torvalds

 *

 * m68k version by Andreas Schwab

 */

struct semaphore {

        atomic_t count;

        atomic_t waking;

        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_INITIALIZER(name,count) \

{ ATOMIC_INIT(count), ATOMIC_INIT(0), __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \

        __SEM_DEBUG_INIT(name) }

#define __MUTEX_INITIALIZER(name) \

        __SEMAPHORE_INITIALIZER(name,1)

#define __DECLARE_SEMAPHORE_GENERIC(name,count) \

        struct semaphore name = __SEMAPHORE_INITIALIZER(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)

{

        *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val);

}

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);

}

asmlinkage void __down_failed(void /* special register calling convention */);

asmlinkage int  __down_failed_interruptible(void  /* params in registers */);

asmlinkage int  __down_failed_trylock(void  /* params in registers */);

asmlinkage void __up_wakeup(void /* special register calling convention */);

asmlinkage void __down(struct semaphore * sem);

asmlinkage int  __down_interruptible(struct semaphore * sem);

asmlinkage int  __down_trylock(struct semaphore * sem);

asmlinkage void __up(struct semaphore * sem);

/*

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

 * "down_failed" is a special asm handler that calls the C

 * routine that actually waits. See arch/m68k/lib/semaphore.S

 */

static inline void down(struct semaphore *sem)

{

        register struct semaphore *sem1 __asm__ ("%a1") = sem;

#if WAITQUEUE_DEBUG

        CHECK_MAGIC(sem->__magic);

#endif

        __asm__ __volatile__(

                "| atomic down operation\n\t"

                "subql #1,%0@\n\t"

                "jmi 2f\n\t"

                "1:\n"

                LOCK_SECTION_START(".even\n\t")

                "2:\tpea 1b\n\t"

                "jbra __down_failed\n"

                LOCK_SECTION_END

                : /* no outputs */

                : "a" (sem1)

                : "memory");

}

static inline int down_interruptible(struct semaphore *sem)

{

        register struct semaphore *sem1 __asm__ ("%a1") = sem;

        register int result __asm__ ("%d0");

#if WAITQUEUE_DEBUG

        CHECK_MAGIC(sem->__magic);

#endif

        __asm__ __volatile__(

                "| atomic interruptible down operation\n\t"

                "subql #1,%1@\n\t"

                "jmi 2f\n\t"

                "clrl %0\n"

                "1:\n"

                LOCK_SECTION_START(".even\n\t")

                "2:\tpea 1b\n\t"

                "jbra __down_failed_interruptible\n"

                LOCK_SECTION_END

                : "=d" (result)

                : "a" (sem1)

                : "memory");

        return result;

}

static inline int down_trylock(struct semaphore *sem)

{

        register struct semaphore *sem1 __asm__ ("%a1") = sem;

        register int result __asm__ ("%d0");

#if WAITQUEUE_DEBUG

        CHECK_MAGIC(sem->__magic);

#endif

        __asm__ __volatile__(

                "| atomic down trylock operation\n\t"

                "subql #1,%1@\n\t"

                "jmi 2f\n\t"

                "clrl %0\n"

                "1:\n"

                LOCK_SECTION_START(".even\n\t")

                "2:\tpea 1b\n\t"

                "jbra __down_failed_trylock\n"

                LOCK_SECTION_END

                : "=d" (result)

                : "a" (sem1)

                : "memory");

        return result;

}

/*

 * 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)

{

        register struct semaphore *sem1 __asm__ ("%a1") = sem;

#if WAITQUEUE_DEBUG

        CHECK_MAGIC(sem->__magic);

#endif

        __asm__ __volatile__(

                "| atomic up operation\n\t"

                "addql #1,%0@\n\t"

                "jle 2f\n"

                "1:\n"

                LOCK_SECTION_START(".even\n\t")

                "2:\t"

                "pea 1b\n\t"

                "jbra __up_wakeup\n"

                LOCK_SECTION_END

                : /* no outputs */

                : "a" (sem1)

                : "memory");

}

static inline int sem_getcount(struct semaphore *sem)

{

        return atomic_read(&sem->count);

}

#endif /* __ASSEMBLY__ */

#endif