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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_GENERIC_BITOPS_ATOMIC_H_
#define _ASM_GENERIC_BITOPS_ATOMIC_H_
#include <linux/atomic.h>
#include <linux/compiler.h>
#include <asm/barrier.h>
/*
* Implementation of atomic bitops using atomic-fetch ops.
* See Documentation/atomic_bitops.txt for details.
*/
static __always_inline void set_bit(unsigned int nr, volatile unsigned long *p)
{
p += BIT_WORD(nr);
atomic_long_or(BIT_MASK(nr), (atomic_long_t *)p);
}
static __always_inline void clear_bit(unsigned int nr, volatile unsigned long *p)
{
p += BIT_WORD(nr);
atomic_long_andnot(BIT_MASK(nr), (atomic_long_t *)p);
}
static __always_inline void change_bit(unsigned int nr, volatile unsigned long *p)
{
p += BIT_WORD(nr);
atomic_long_xor(BIT_MASK(nr), (atomic_long_t *)p);
}
static inline int test_and_set_bit(unsigned int nr, volatile unsigned long *p)
{
long old;
unsigned long mask = BIT_MASK(nr);
p += BIT_WORD(nr);
if (READ_ONCE(*p) & mask)
return 1;
old = atomic_long_fetch_or(mask, (atomic_long_t *)p);
return !!(old & mask);
}
static inline int test_and_clear_bit(unsigned int nr, volatile unsigned long *p)
{
long old;
unsigned long mask = BIT_MASK(nr);
p += BIT_WORD(nr);
if (!(READ_ONCE(*p) & mask))
return 0;
old = atomic_long_fetch_andnot(mask, (atomic_long_t *)p);
return !!(old & mask);
}
static inline int test_and_change_bit(unsigned int nr, volatile unsigned long *p)
{
long old;
unsigned long mask = BIT_MASK(nr);
p += BIT_WORD(nr);
old = atomic_long_fetch_xor(mask, (atomic_long_t *)p);
return !!(old & mask);
}
#endif /* _ASM_GENERIC_BITOPS_ATOMIC_H */
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