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linux-2.6/include/asm-h8300/semaphore.h
Christoph Hellwig 04fc8bbcf5 kill DECLARE_MUTEX_LOCKED
DECLARE_MUTEX_LOCKED was used for semaphores used as completions and we've
got rid of them.  Well, except for one in libusual that the maintainer
explicitly wants to keep as semaphore.  So convert that useage to an
explicit sema_init and kill of DECLARE_MUTEX_LOCKED so that new code is
reminded to use a completion.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: "Satyam Sharma" <satyam.sharma@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-17 08:42:47 -07:00

191 lines
4.1 KiB
C

#ifndef _H8300_SEMAPHORE_H
#define _H8300_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
*
* H8/300 version by Yoshinori Sato
*/
struct semaphore {
atomic_t count;
int sleepers;
wait_queue_head_t wait;
};
#define __SEMAPHORE_INITIALIZER(name, n) \
{ \
.count = ATOMIC_INIT(n), \
.sleepers = 0, \
.wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
}
#define __DECLARE_SEMAPHORE_GENERIC(name,count) \
struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
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);
extern spinlock_t semaphore_wake_lock;
/*
* 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 atomic_t *count asm("er0");
might_sleep();
count = &(sem->count);
__asm__ __volatile__(
"stc ccr,r3l\n\t"
"orc #0x80,ccr\n\t"
"mov.l %2, er1\n\t"
"dec.l #1,er1\n\t"
"mov.l er1,%0\n\t"
"bpl 1f\n\t"
"ldc r3l,ccr\n\t"
"mov.l %1,er0\n\t"
"jsr @___down\n\t"
"bra 2f\n"
"1:\n\t"
"ldc r3l,ccr\n"
"2:"
: "=m"(*count)
: "g"(sem),"m"(*count)
: "cc", "er1", "er2", "er3");
}
static inline int down_interruptible(struct semaphore * sem)
{
register atomic_t *count asm("er0");
might_sleep();
count = &(sem->count);
__asm__ __volatile__(
"stc ccr,r1l\n\t"
"orc #0x80,ccr\n\t"
"mov.l %3, er2\n\t"
"dec.l #1,er2\n\t"
"mov.l er2,%1\n\t"
"bpl 1f\n\t"
"ldc r1l,ccr\n\t"
"mov.l %2,er0\n\t"
"jsr @___down_interruptible\n\t"
"bra 2f\n"
"1:\n\t"
"ldc r1l,ccr\n\t"
"sub.l %0,%0\n\t"
"2:\n\t"
: "=r" (count),"=m" (*count)
: "g"(sem),"m"(*count)
: "cc", "er1", "er2", "er3");
return (int)count;
}
static inline int down_trylock(struct semaphore * sem)
{
register atomic_t *count asm("er0");
count = &(sem->count);
__asm__ __volatile__(
"stc ccr,r3l\n\t"
"orc #0x80,ccr\n\t"
"mov.l %3,er2\n\t"
"dec.l #1,er2\n\t"
"mov.l er2,%0\n\t"
"bpl 1f\n\t"
"ldc r3l,ccr\n\t"
"jmp @3f\n\t"
LOCK_SECTION_START(".align 2\n\t")
"3:\n\t"
"mov.l %2,er0\n\t"
"jsr @___down_trylock\n\t"
"jmp @2f\n\t"
LOCK_SECTION_END
"1:\n\t"
"ldc r3l,ccr\n\t"
"sub.l %1,%1\n"
"2:"
: "=m" (*count),"=r"(count)
: "g"(sem),"m"(*count)
: "cc", "er1","er2", "er3");
return (int)count;
}
/*
* 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 atomic_t *count asm("er0");
count = &(sem->count);
__asm__ __volatile__(
"stc ccr,r3l\n\t"
"orc #0x80,ccr\n\t"
"mov.l %2,er1\n\t"
"inc.l #1,er1\n\t"
"mov.l er1,%0\n\t"
"ldc r3l,ccr\n\t"
"sub.l er2,er2\n\t"
"cmp.l er2,er1\n\t"
"bgt 1f\n\t"
"mov.l %1,er0\n\t"
"jsr @___up\n"
"1:"
: "=m"(*count)
: "g"(sem),"m"(*count)
: "cc", "er1", "er2", "er3");
}
#endif /* __ASSEMBLY__ */
#endif