/* * 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/locks.h> struct semaphore {	atomic_t count;	int sleepers;	wait_queue_head_t wait;}; #define __SEMAPHORE_INIT(name, cnt)				\{								\	.count	= ATOMIC_INIT(cnt),				\	.wait	= __WAIT_QUEUE_HEAD_INITIALIZER((name).wait),	\} #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);} 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){	might_sleep();	__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){	might_sleep();	return __down_op_ret(sem, __down_interruptible_failed);} static inline int down_trylock(struct semaphore *sem){	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){	__up_op(sem, __up_wakeup);} #endif