1*819833afSPeter Tyser #ifndef _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ 2*819833afSPeter Tyser #define _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ 3*819833afSPeter Tyser 4*819833afSPeter Tyser #include <asm/types.h> 5*819833afSPeter Tyser 6*819833afSPeter Tyser /** 7*819833afSPeter Tyser * __set_bit - Set a bit in memory 8*819833afSPeter Tyser * @nr: the bit to set 9*819833afSPeter Tyser * @addr: the address to start counting from 10*819833afSPeter Tyser * 11*819833afSPeter Tyser * Unlike set_bit(), this function is non-atomic and may be reordered. 12*819833afSPeter Tyser * If it's called on the same region of memory simultaneously, the effect 13*819833afSPeter Tyser * may be that only one operation succeeds. 14*819833afSPeter Tyser */ 15*819833afSPeter Tyser static inline void __set_bit(int nr, volatile unsigned long *addr) 16*819833afSPeter Tyser { 17*819833afSPeter Tyser unsigned long mask = BIT_MASK(nr); 18*819833afSPeter Tyser unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); 19*819833afSPeter Tyser 20*819833afSPeter Tyser *p |= mask; 21*819833afSPeter Tyser } 22*819833afSPeter Tyser 23*819833afSPeter Tyser static inline void __clear_bit(int nr, volatile unsigned long *addr) 24*819833afSPeter Tyser { 25*819833afSPeter Tyser unsigned long mask = BIT_MASK(nr); 26*819833afSPeter Tyser unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); 27*819833afSPeter Tyser 28*819833afSPeter Tyser *p &= ~mask; 29*819833afSPeter Tyser } 30*819833afSPeter Tyser 31*819833afSPeter Tyser /** 32*819833afSPeter Tyser * __change_bit - Toggle a bit in memory 33*819833afSPeter Tyser * @nr: the bit to change 34*819833afSPeter Tyser * @addr: the address to start counting from 35*819833afSPeter Tyser * 36*819833afSPeter Tyser * Unlike change_bit(), this function is non-atomic and may be reordered. 37*819833afSPeter Tyser * If it's called on the same region of memory simultaneously, the effect 38*819833afSPeter Tyser * may be that only one operation succeeds. 39*819833afSPeter Tyser */ 40*819833afSPeter Tyser static inline void __change_bit(int nr, volatile unsigned long *addr) 41*819833afSPeter Tyser { 42*819833afSPeter Tyser unsigned long mask = BIT_MASK(nr); 43*819833afSPeter Tyser unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); 44*819833afSPeter Tyser 45*819833afSPeter Tyser *p ^= mask; 46*819833afSPeter Tyser } 47*819833afSPeter Tyser 48*819833afSPeter Tyser /** 49*819833afSPeter Tyser * __test_and_set_bit - Set a bit and return its old value 50*819833afSPeter Tyser * @nr: Bit to set 51*819833afSPeter Tyser * @addr: Address to count from 52*819833afSPeter Tyser * 53*819833afSPeter Tyser * This operation is non-atomic and can be reordered. 54*819833afSPeter Tyser * If two examples of this operation race, one can appear to succeed 55*819833afSPeter Tyser * but actually fail. You must protect multiple accesses with a lock. 56*819833afSPeter Tyser */ 57*819833afSPeter Tyser static inline int __test_and_set_bit(int nr, volatile unsigned long *addr) 58*819833afSPeter Tyser { 59*819833afSPeter Tyser unsigned long mask = BIT_MASK(nr); 60*819833afSPeter Tyser unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); 61*819833afSPeter Tyser unsigned long old = *p; 62*819833afSPeter Tyser 63*819833afSPeter Tyser *p = old | mask; 64*819833afSPeter Tyser return (old & mask) != 0; 65*819833afSPeter Tyser } 66*819833afSPeter Tyser 67*819833afSPeter Tyser /** 68*819833afSPeter Tyser * __test_and_clear_bit - Clear a bit and return its old value 69*819833afSPeter Tyser * @nr: Bit to clear 70*819833afSPeter Tyser * @addr: Address to count from 71*819833afSPeter Tyser * 72*819833afSPeter Tyser * This operation is non-atomic and can be reordered. 73*819833afSPeter Tyser * If two examples of this operation race, one can appear to succeed 74*819833afSPeter Tyser * but actually fail. You must protect multiple accesses with a lock. 75*819833afSPeter Tyser */ 76*819833afSPeter Tyser static inline int __test_and_clear_bit(int nr, volatile unsigned long *addr) 77*819833afSPeter Tyser { 78*819833afSPeter Tyser unsigned long mask = BIT_MASK(nr); 79*819833afSPeter Tyser unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); 80*819833afSPeter Tyser unsigned long old = *p; 81*819833afSPeter Tyser 82*819833afSPeter Tyser *p = old & ~mask; 83*819833afSPeter Tyser return (old & mask) != 0; 84*819833afSPeter Tyser } 85*819833afSPeter Tyser 86*819833afSPeter Tyser /* WARNING: non atomic and it can be reordered! */ 87*819833afSPeter Tyser static inline int __test_and_change_bit(int nr, 88*819833afSPeter Tyser volatile unsigned long *addr) 89*819833afSPeter Tyser { 90*819833afSPeter Tyser unsigned long mask = BIT_MASK(nr); 91*819833afSPeter Tyser unsigned long *p = ((unsigned long *)addr) + BIT_WORD(nr); 92*819833afSPeter Tyser unsigned long old = *p; 93*819833afSPeter Tyser 94*819833afSPeter Tyser *p = old ^ mask; 95*819833afSPeter Tyser return (old & mask) != 0; 96*819833afSPeter Tyser } 97*819833afSPeter Tyser 98*819833afSPeter Tyser /** 99*819833afSPeter Tyser * test_bit - Determine whether a bit is set 100*819833afSPeter Tyser * @nr: bit number to test 101*819833afSPeter Tyser * @addr: Address to start counting from 102*819833afSPeter Tyser */ 103*819833afSPeter Tyser static inline int test_bit(int nr, const volatile unsigned long *addr) 104*819833afSPeter Tyser { 105*819833afSPeter Tyser return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1))); 106*819833afSPeter Tyser } 107*819833afSPeter Tyser 108*819833afSPeter Tyser #endif /* _ASM_GENERIC_BITOPS_NON_ATOMIC_H_ */ 109