1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_GENERIC_BITOPS_ATOMIC_H_ 3 #define _ASM_GENERIC_BITOPS_ATOMIC_H_ 4 5 #include <linux/atomic.h> 6 #include <linux/compiler.h> 7 #include <asm/barrier.h> 8 9 /* 10 * Implementation of atomic bitops using atomic-fetch ops. 11 * See Documentation/atomic_bitops.txt for details. 12 */ 13 14 static inline void set_bit(unsigned int nr, volatile unsigned long *p) 15 { 16 p += BIT_WORD(nr); 17 atomic_long_or(BIT_MASK(nr), (atomic_long_t *)p); 18 } 19 20 static inline void clear_bit(unsigned int nr, volatile unsigned long *p) 21 { 22 p += BIT_WORD(nr); 23 atomic_long_andnot(BIT_MASK(nr), (atomic_long_t *)p); 24 } 25 26 static inline void change_bit(unsigned int nr, volatile unsigned long *p) 27 { 28 p += BIT_WORD(nr); 29 atomic_long_xor(BIT_MASK(nr), (atomic_long_t *)p); 30 } 31 32 static inline int test_and_set_bit(unsigned int nr, volatile unsigned long *p) 33 { 34 long old; 35 unsigned long mask = BIT_MASK(nr); 36 37 p += BIT_WORD(nr); 38 if (READ_ONCE(*p) & mask) 39 return 1; 40 41 old = atomic_long_fetch_or(mask, (atomic_long_t *)p); 42 return !!(old & mask); 43 } 44 45 static inline int test_and_clear_bit(unsigned int nr, volatile unsigned long *p) 46 { 47 long old; 48 unsigned long mask = BIT_MASK(nr); 49 50 p += BIT_WORD(nr); 51 if (!(READ_ONCE(*p) & mask)) 52 return 0; 53 54 old = atomic_long_fetch_andnot(mask, (atomic_long_t *)p); 55 return !!(old & mask); 56 } 57 58 static inline int test_and_change_bit(unsigned int nr, volatile unsigned long *p) 59 { 60 long old; 61 unsigned long mask = BIT_MASK(nr); 62 63 p += BIT_WORD(nr); 64 old = atomic_long_fetch_xor(mask, (atomic_long_t *)p); 65 return !!(old & mask); 66 } 67 68 #endif /* _ASM_GENERIC_BITOPS_ATOMIC_H */ 69