include/asm-v850/semaphore.h

   1 #ifndef __V850_SEMAPHORE_H__
   2 #define __V850_SEMAPHORE_H__
   3
   4 #include <linux/linkage.h>
   5 #include <linux/spinlock.h>
   6 #include <linux/wait.h>
   7 #include <linux/rwsem.h>
   8
   9 #include <asm/atomic.h>
  10
  11 struct semaphore {
  12         atomic_t count;
  13         int sleepers;
  14         wait_queue_head_t wait;
  15 };
  16
  17 #define __SEMAPHORE_INITIALIZER(name,count)                                   \
  18         { ATOMIC_INIT (count), 0,                                             \
  19           __WAIT_QUEUE_HEAD_INITIALIZER ((name).wait) }
  20
  21 #define __DECLARE_SEMAPHORE_GENERIC(name,count) \
  22         struct semaphore name = __SEMAPHORE_INITIALIZER (name,count)
  23
  24 #define DECLARE_MUTEX(name)             __DECLARE_SEMAPHORE_GENERIC (name,1)
  25 #define DECLARE_MUTEX_LOCKED(name)      __DECLARE_SEMAPHORE_GENERIC (name,0)
  26
  27 static inline void sema_init (struct semaphore *sem, int val)
  28 {
  29         *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val);
  30 }
  31
  32 static inline void init_MUTEX (struct semaphore *sem)
  33 {
  34         sema_init (sem, 1);
  35 }
  36
  37 static inline void init_MUTEX_LOCKED (struct semaphore *sem)
  38 {
  39         sema_init (sem, 0);
  40 }
  41
  42 /*
  43  * special register calling convention
  44  */
  45 asmlinkage void __down_failed (void);
  46 asmlinkage int  __down_interruptible_failed (void);
  47 asmlinkage int  __down_trylock_failed (void);
  48 asmlinkage void __up_wakeup (void);
  49
  50 extern void __down (struct semaphore * sem);
  51 extern int  __down_interruptible (struct semaphore * sem);
  52 extern int  __down_trylock (struct semaphore * sem);
  53 extern void __up (struct semaphore * sem);
  54
  55 static inline void down (struct semaphore * sem)
  56 {
  57         might_sleep();
  58         if (atomic_dec_return (&sem->count) < 0)
  59                 __down (sem);
  60 }
  61
  62 static inline int down_interruptible (struct semaphore * sem)
  63 {
  64         int ret = 0;
  65         might_sleep();
  66         if (atomic_dec_return (&sem->count) < 0)
  67                 ret = __down_interruptible (sem);
  68         return ret;
  69 }
  70
  71 static inline int down_trylock (struct semaphore *sem)
  72 {
  73         int ret = 0;
  74         if (atomic_dec_return (&sem->count) < 0)
  75                 ret = __down_trylock (sem);
  76         return ret;
  77 }
  78
  79 static inline void up (struct semaphore * sem)
  80 {
  81         if (atomic_inc_return (&sem->count) <= 0)
  82                 __up (sem);
  83 }
  84
  85 #endif /* __V850_SEMAPHORE_H__ */