04fc8bbcf5
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>
154 lines
3.5 KiB
C
154 lines
3.5 KiB
C
#ifndef _M68K_SEMAPHORE_H
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#define _M68K_SEMAPHORE_H
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#define RW_LOCK_BIAS 0x01000000
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#ifndef __ASSEMBLY__
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#include <linux/linkage.h>
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#include <linux/wait.h>
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#include <linux/spinlock.h>
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#include <linux/rwsem.h>
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#include <asm/system.h>
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#include <asm/atomic.h>
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/*
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* Interrupt-safe semaphores..
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*
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* (C) Copyright 1996 Linus Torvalds
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*
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* m68k version by Andreas Schwab
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*/
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struct semaphore {
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atomic_t count;
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atomic_t waking;
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wait_queue_head_t wait;
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};
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#define __SEMAPHORE_INITIALIZER(name, n) \
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{ \
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.count = ATOMIC_INIT(n), \
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.waking = ATOMIC_INIT(0), \
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.wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \
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}
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#define __DECLARE_SEMAPHORE_GENERIC(name,count) \
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struct semaphore name = __SEMAPHORE_INITIALIZER(name,count)
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#define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1)
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static inline void sema_init (struct semaphore *sem, int val)
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{
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*sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val);
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}
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static inline void init_MUTEX (struct semaphore *sem)
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{
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sema_init(sem, 1);
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}
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static inline void init_MUTEX_LOCKED (struct semaphore *sem)
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{
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sema_init(sem, 0);
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}
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asmlinkage void __down_failed(void /* special register calling convention */);
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asmlinkage int __down_failed_interruptible(void /* params in registers */);
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asmlinkage int __down_failed_trylock(void /* params in registers */);
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asmlinkage void __up_wakeup(void /* special register calling convention */);
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asmlinkage void __down(struct semaphore * sem);
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asmlinkage int __down_interruptible(struct semaphore * sem);
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asmlinkage int __down_trylock(struct semaphore * sem);
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asmlinkage void __up(struct semaphore * sem);
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extern spinlock_t semaphore_wake_lock;
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/*
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* This is ugly, but we want the default case to fall through.
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* "down_failed" is a special asm handler that calls the C
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* routine that actually waits. See arch/m68k/lib/semaphore.S
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*/
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static inline void down(struct semaphore * sem)
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{
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might_sleep();
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__asm__ __volatile__(
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"| atomic down operation\n\t"
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"movel %0, %%a1\n\t"
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"lea %%pc@(1f), %%a0\n\t"
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"subql #1, %%a1@\n\t"
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"jmi __down_failed\n"
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"1:"
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: /* no outputs */
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: "g" (sem)
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: "cc", "%a0", "%a1", "memory");
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}
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static inline int down_interruptible(struct semaphore * sem)
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{
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int ret;
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might_sleep();
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__asm__ __volatile__(
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"| atomic down operation\n\t"
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"movel %1, %%a1\n\t"
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"lea %%pc@(1f), %%a0\n\t"
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"subql #1, %%a1@\n\t"
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"jmi __down_failed_interruptible\n\t"
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"clrl %%d0\n"
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"1: movel %%d0, %0\n"
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: "=d" (ret)
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: "g" (sem)
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: "cc", "%d0", "%a0", "%a1", "memory");
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return(ret);
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}
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static inline int down_trylock(struct semaphore * sem)
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{
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register struct semaphore *sem1 __asm__ ("%a1") = sem;
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register int result __asm__ ("%d0");
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__asm__ __volatile__(
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"| atomic down trylock operation\n\t"
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"subql #1,%1@\n\t"
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"jmi 2f\n\t"
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"clrl %0\n"
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"1:\n"
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".section .text.lock,\"ax\"\n"
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".even\n"
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"2:\tpea 1b\n\t"
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"jbra __down_failed_trylock\n"
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".previous"
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: "=d" (result)
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: "a" (sem1)
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: "memory");
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return result;
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}
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/*
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* Note! This is subtle. We jump to wake people up only if
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* the semaphore was negative (== somebody was waiting on it).
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* The default case (no contention) will result in NO
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* jumps for both down() and up().
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*/
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static inline void up(struct semaphore * sem)
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{
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__asm__ __volatile__(
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"| atomic up operation\n\t"
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"movel %0, %%a1\n\t"
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"lea %%pc@(1f), %%a0\n\t"
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"addql #1, %%a1@\n\t"
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"jle __up_wakeup\n"
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"1:"
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: /* no outputs */
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: "g" (sem)
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: "cc", "%a0", "%a1", "memory");
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}
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#endif /* __ASSEMBLY__ */
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#endif
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