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/* SPDX-License-Identifier: GPL-2.0 */#ifndef _ASM_GENERIC_BITOPS_LOCK_H_#define _ASM_GENERIC_BITOPS_LOCK_H_ #include <linux/atomic.h>#include <linux/compiler.h>#include <asm/barrier.h> /** * arch_test_and_set_bit_lock - Set a bit and return its old value, for lock * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and provides acquire barrier semantics if * the returned value is 0. * It can be used to implement bit locks. */static __always_inline intarch_test_and_set_bit_lock(unsigned int nr, volatile unsigned long *addr){	long old;	unsigned long mask = BIT_MASK(nr); 	addr += BIT_WORD(nr);	if (READ_ONCE(*addr) & mask)		return 1; 	old = raw_atomic_long_fetch_or_acquire(mask, (atomic_long_t *)addr);	return !!(old & mask);}  /** * arch_clear_bit_unlock - Clear a bit in memory, for unlock * @nr: the bit to set * @addr: the address to start counting from * * This operation is atomic and provides release barrier semantics. */static __always_inline voidarch_clear_bit_unlock(unsigned int nr, volatile unsigned long *addr){	addr += BIT_WORD(nr);	raw_atomic_long_fetch_andnot_release(BIT_MASK(nr), (atomic_long_t *)addr);} /** * arch___clear_bit_unlock - Clear a bit in memory, for unlock * @nr: the bit to set * @addr: the address to start counting from * * A weaker form of clear_bit_unlock() as used by __bit_lock_unlock(). If all * the bits in the word are protected by this lock some archs can use weaker * ops to safely unlock. * * See for example x86's implementation. */static inline voidarch___clear_bit_unlock(unsigned int nr, volatile unsigned long *addr){	unsigned long old; 	addr += BIT_WORD(nr);	old = READ_ONCE(*addr);	old &= ~BIT_MASK(nr);	raw_atomic_long_set_release((atomic_long_t *)addr, old);} #ifndef arch_xor_unlock_is_negative_bytestatic inline bool arch_xor_unlock_is_negative_byte(unsigned long mask,		volatile unsigned long *p){	long old; 	old = raw_atomic_long_fetch_xor_release(mask, (atomic_long_t *)p);	return !!(old & BIT(7));}#endif #include <asm-generic/bitops/instrumented-lock.h> #endif /* _ASM_GENERIC_BITOPS_LOCK_H_ */