1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* atomic.h: Thankfully the V9 is at least reasonable for this 3 * stuff. 4 * 5 * Copyright (C) 1996, 1997, 2000, 2012 David S. Miller (davem@redhat.com) 6 */ 7 8 #ifndef __ARCH_SPARC64_ATOMIC__ 9 #define __ARCH_SPARC64_ATOMIC__ 10 11 #include <linux/types.h> 12 #include <asm/cmpxchg.h> 13 #include <asm/barrier.h> 14 15 #define ATOMIC_INIT(i) { (i) } 16 #define ATOMIC64_INIT(i) { (i) } 17 18 #define atomic_read(v) READ_ONCE((v)->counter) 19 #define atomic64_read(v) READ_ONCE((v)->counter) 20 21 #define atomic_set(v, i) WRITE_ONCE(((v)->counter), (i)) 22 #define atomic64_set(v, i) WRITE_ONCE(((v)->counter), (i)) 23 24 #define ATOMIC_OP(op) \ 25 void atomic_##op(int, atomic_t *); \ 26 void atomic64_##op(long, atomic64_t *); 27 28 #define ATOMIC_OP_RETURN(op) \ 29 int atomic_##op##_return(int, atomic_t *); \ 30 long atomic64_##op##_return(long, atomic64_t *); 31 32 #define ATOMIC_FETCH_OP(op) \ 33 int atomic_fetch_##op(int, atomic_t *); \ 34 long atomic64_fetch_##op(long, atomic64_t *); 35 36 #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_OP_RETURN(op) ATOMIC_FETCH_OP(op) 37 38 ATOMIC_OPS(add) 39 ATOMIC_OPS(sub) 40 41 #undef ATOMIC_OPS 42 #define ATOMIC_OPS(op) ATOMIC_OP(op) ATOMIC_FETCH_OP(op) 43 44 ATOMIC_OPS(and) 45 ATOMIC_OPS(or) 46 ATOMIC_OPS(xor) 47 48 #undef ATOMIC_OPS 49 #undef ATOMIC_FETCH_OP 50 #undef ATOMIC_OP_RETURN 51 #undef ATOMIC_OP 52 53 #define atomic_dec_return(v) atomic_sub_return(1, v) 54 #define atomic64_dec_return(v) atomic64_sub_return(1, v) 55 56 #define atomic_inc_return(v) atomic_add_return(1, v) 57 #define atomic64_inc_return(v) atomic64_add_return(1, v) 58 59 /* 60 * atomic_inc_and_test - increment and test 61 * @v: pointer of type atomic_t 62 * 63 * Atomically increments @v by 1 64 * and returns true if the result is zero, or false for all 65 * other cases. 66 */ 67 #define atomic_inc_and_test(v) (atomic_inc_return(v) == 0) 68 #define atomic64_inc_and_test(v) (atomic64_inc_return(v) == 0) 69 70 #define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0) 71 #define atomic64_sub_and_test(i, v) (atomic64_sub_return(i, v) == 0) 72 73 #define atomic_dec_and_test(v) (atomic_sub_return(1, v) == 0) 74 #define atomic64_dec_and_test(v) (atomic64_sub_return(1, v) == 0) 75 76 #define atomic_inc(v) atomic_add(1, v) 77 #define atomic64_inc(v) atomic64_add(1, v) 78 79 #define atomic_dec(v) atomic_sub(1, v) 80 #define atomic64_dec(v) atomic64_sub(1, v) 81 82 #define atomic_add_negative(i, v) (atomic_add_return(i, v) < 0) 83 #define atomic64_add_negative(i, v) (atomic64_add_return(i, v) < 0) 84 85 #define atomic_cmpxchg(v, o, n) (cmpxchg(&((v)->counter), (o), (n))) 86 87 static inline int atomic_xchg(atomic_t *v, int new) 88 { 89 return xchg(&v->counter, new); 90 } 91 92 static inline int __atomic_add_unless(atomic_t *v, int a, int u) 93 { 94 int c, old; 95 c = atomic_read(v); 96 for (;;) { 97 if (unlikely(c == (u))) 98 break; 99 old = atomic_cmpxchg((v), c, c + (a)); 100 if (likely(old == c)) 101 break; 102 c = old; 103 } 104 return c; 105 } 106 107 #define atomic64_cmpxchg(v, o, n) \ 108 ((__typeof__((v)->counter))cmpxchg(&((v)->counter), (o), (n))) 109 #define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) 110 111 static inline long atomic64_add_unless(atomic64_t *v, long a, long u) 112 { 113 long c, old; 114 c = atomic64_read(v); 115 for (;;) { 116 if (unlikely(c == (u))) 117 break; 118 old = atomic64_cmpxchg((v), c, c + (a)); 119 if (likely(old == c)) 120 break; 121 c = old; 122 } 123 return c != (u); 124 } 125 126 #define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) 127 128 long atomic64_dec_if_positive(atomic64_t *v); 129 130 #endif /* !(__ARCH_SPARC64_ATOMIC__) */ 131