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#ifndef __ASM_ARCH_SPINLOCK_H
#define __ASM_ARCH_SPINLOCK_H
#include <linux/spinlock_types.h>
#define RW_LOCK_BIAS 0x01000000
extern void cris_spin_unlock(void *l, int val);
extern void cris_spin_lock(void *l);
extern int cris_spin_trylock(void *l);
static inline int arch_spin_is_locked(arch_spinlock_t *x)
{
return *(volatile signed char *)(&(x)->slock) <= 0;
}
static inline void arch_spin_unlock(arch_spinlock_t *lock)
{
__asm__ volatile ("move.d %1,%0" \
: "=m" (lock->slock) \
: "r" (1) \
: "memory");
}
static inline void arch_spin_unlock_wait(arch_spinlock_t *lock)
{
while (arch_spin_is_locked(lock))
cpu_relax();
}
static inline int arch_spin_trylock(arch_spinlock_t *lock)
{
return cris_spin_trylock((void *)&lock->slock);
}
static inline void arch_spin_lock(arch_spinlock_t *lock)
{
cris_spin_lock((void *)&lock->slock);
}
static inline void
arch_spin_lock_flags(arch_spinlock_t *lock, unsigned long flags)
{
arch_spin_lock(lock);
}
/*
* Read-write spinlocks, allowing multiple readers
* but only one writer.
*
* NOTE! it is quite common to have readers in interrupts
* but no interrupt writers. For those circumstances we
* can "mix" irq-safe locks - any writer needs to get a
* irq-safe write-lock, but readers can get non-irqsafe
* read-locks.
*
*/
static inline int __raw_read_can_lock(raw_rwlock_t *x)
{
return (int)(x)->lock > 0;
}
static inline int __raw_write_can_lock(raw_rwlock_t *x)
{
return (x)->lock == RW_LOCK_BIAS;
}
static inline void __raw_read_lock(raw_rwlock_t *rw)
{
arch_spin_lock(&rw->slock);
while (rw->lock == 0);
rw->lock--;
arch_spin_unlock(&rw->slock);
}
static inline void __raw_write_lock(raw_rwlock_t *rw)
{
arch_spin_lock(&rw->slock);
while (rw->lock != RW_LOCK_BIAS);
rw->lock = 0;
arch_spin_unlock(&rw->slock);
}
static inline void __raw_read_unlock(raw_rwlock_t *rw)
{
arch_spin_lock(&rw->slock);
rw->lock++;
arch_spin_unlock(&rw->slock);
}
static inline void __raw_write_unlock(raw_rwlock_t *rw)
{
arch_spin_lock(&rw->slock);
while (rw->lock != RW_LOCK_BIAS);
rw->lock = RW_LOCK_BIAS;
arch_spin_unlock(&rw->slock);
}
static inline int __raw_read_trylock(raw_rwlock_t *rw)
{
int ret = 0;
arch_spin_lock(&rw->slock);
if (rw->lock != 0) {
rw->lock--;
ret = 1;
}
arch_spin_unlock(&rw->slock);
return ret;
}
static inline int __raw_write_trylock(raw_rwlock_t *rw)
{
int ret = 0;
arch_spin_lock(&rw->slock);
if (rw->lock == RW_LOCK_BIAS) {
rw->lock = 0;
ret = 1;
}
arch_spin_unlock(&rw->slock);
return 1;
}
#define _raw_read_lock_flags(lock, flags) _raw_read_lock(lock)
#define _raw_write_lock_flags(lock, flags) _raw_write_lock(lock)
#define arch_spin_relax(lock) cpu_relax()
#define arch_read_relax(lock) cpu_relax()
#define arch_write_relax(lock) cpu_relax()
#endif /* __ASM_ARCH_SPINLOCK_H */
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