1 #ifndef _M68K_SEMAPHORE_H
2 #define _M68K_SEMAPHORE_H
4 #define RW_LOCK_BIAS 0x01000000
8 #include <linux/linkage.h>
9 #include <linux/wait.h>
10 #include <linux/spinlock.h>
11 #include <linux/rwsem.h>
13 #include <asm/system.h>
14 #include <asm/atomic.h>
17 * Interrupt-safe semaphores..
19 * (C) Copyright 1996 Linus Torvalds
21 * m68k version by Andreas Schwab
28 wait_queue_head_t wait;
35 # define __SEM_DEBUG_INIT(name) \
36 , (long)&(name).__magic
38 # define __SEM_DEBUG_INIT(name)
41 #define __SEMAPHORE_INITIALIZER(name,count) \
42 { ATOMIC_INIT(count), ATOMIC_INIT(0), __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
43 __SEM_DEBUG_INIT(name) }
45 #define __MUTEX_INITIALIZER(name) \
46 __SEMAPHORE_INITIALIZER(name,1)
48 #define __DECLARE_SEMAPHORE_GENERIC(name,count) \
49 struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
51 #define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
52 #define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0)
54 extern inline void sema_init (struct semaphore *sem, int val)
56 *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val);
59 static inline void init_MUTEX (struct semaphore *sem)
64 static inline void init_MUTEX_LOCKED (struct semaphore *sem)
69 asmlinkage void __down_failed(void /* special register calling convention */);
70 asmlinkage int __down_failed_interruptible(void /* params in registers */);
71 asmlinkage int __down_failed_trylock(void /* params in registers */);
72 asmlinkage void __up_wakeup(void /* special register calling convention */);
74 asmlinkage void __down(struct semaphore * sem);
75 asmlinkage int __down_interruptible(struct semaphore * sem);
76 asmlinkage int __down_trylock(struct semaphore * sem);
77 asmlinkage void __up(struct semaphore * sem);
80 * This is ugly, but we want the default case to fall through.
81 * "down_failed" is a special asm handler that calls the C
82 * routine that actually waits. See arch/m68k/lib/semaphore.S
84 extern inline void down(struct semaphore * sem)
86 register struct semaphore *sem1 __asm__ ("%a1") = sem;
89 CHECK_MAGIC(sem->__magic);
93 "| atomic down operation\n\t"
97 LOCK_SECTION_START(".even\n\t")
99 "jbra __down_failed\n"
106 extern inline int down_interruptible(struct semaphore * sem)
108 register struct semaphore *sem1 __asm__ ("%a1") = sem;
109 register int result __asm__ ("%d0");
112 CHECK_MAGIC(sem->__magic);
115 __asm__ __volatile__(
116 "| atomic interruptible down operation\n\t"
121 LOCK_SECTION_START(".even\n\t")
123 "jbra __down_failed_interruptible\n"
131 extern inline int down_trylock(struct semaphore * sem)
133 register struct semaphore *sem1 __asm__ ("%a1") = sem;
134 register int result __asm__ ("%d0");
137 CHECK_MAGIC(sem->__magic);
140 __asm__ __volatile__(
141 "| atomic down trylock operation\n\t"
146 LOCK_SECTION_START(".even\n\t")
148 "jbra __down_failed_trylock\n"
157 * Note! This is subtle. We jump to wake people up only if
158 * the semaphore was negative (== somebody was waiting on it).
159 * The default case (no contention) will result in NO
160 * jumps for both down() and up().
162 extern inline void up(struct semaphore * sem)
164 register struct semaphore *sem1 __asm__ ("%a1") = sem;
167 CHECK_MAGIC(sem->__magic);
170 __asm__ __volatile__(
171 "| atomic up operation\n\t"
175 LOCK_SECTION_START(".even\n\t")
186 static inline int sem_getcount(struct semaphore *sem)
188 return atomic_read(&sem->count);
191 #endif /* __ASSEMBLY__ */