1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef _ASM_X86_CMPXCHG_64_H 3#define _ASM_X86_CMPXCHG_64_H 4 5#define arch_cmpxchg64(ptr, o, n) \ 6({ \ 7 BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ 8 arch_cmpxchg((ptr), (o), (n)); \ 9}) 10 11#define arch_cmpxchg64_local(ptr, o, n) \ 12({ \ 13 BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ 14 arch_cmpxchg_local((ptr), (o), (n)); \ 15}) 16 17#define arch_try_cmpxchg64(ptr, po, n) \ 18({ \ 19 BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ 20 arch_try_cmpxchg((ptr), (po), (n)); \ 21}) 22 23union __u128_halves { 24 u128 full; 25 struct { 26 u64 low, high; 27 }; 28}; 29 30#define __arch_cmpxchg128(_ptr, _old, _new, _lock) \ 31({ \ 32 union __u128_halves o = { .full = (_old), }, \ 33 n = { .full = (_new), }; \ 34 \ 35 asm volatile(_lock "cmpxchg16b %[ptr]" \ 36 : [ptr] "+m" (*(_ptr)), \ 37 "+a" (o.low), "+d" (o.high) \ 38 : "b" (n.low), "c" (n.high) \ 39 : "memory"); \ 40 \ 41 o.full; \ 42}) 43 44static __always_inline u128 arch_cmpxchg128(volatile u128 *ptr, u128 old, u128 new) 45{ 46 return __arch_cmpxchg128(ptr, old, new, LOCK_PREFIX); 47} 48#define arch_cmpxchg128 arch_cmpxchg128 49 50static __always_inline u128 arch_cmpxchg128_local(volatile u128 *ptr, u128 old, u128 new) 51{ 52 return __arch_cmpxchg128(ptr, old, new,); 53} 54#define arch_cmpxchg128_local arch_cmpxchg128_local 55 56#define __arch_try_cmpxchg128(_ptr, _oldp, _new, _lock) \ 57({ \ 58 union __u128_halves o = { .full = *(_oldp), }, \ 59 n = { .full = (_new), }; \ 60 bool ret; \ 61 \ 62 asm volatile(_lock "cmpxchg16b %[ptr]" \ 63 CC_SET(e) \ 64 : CC_OUT(e) (ret), \ 65 [ptr] "+m" (*ptr), \ 66 "+a" (o.low), "+d" (o.high) \ 67 : "b" (n.low), "c" (n.high) \ 68 : "memory"); \ 69 \ 70 if (unlikely(!ret)) \ 71 *(_oldp) = o.full; \ 72 \ 73 likely(ret); \ 74}) 75 76static __always_inline bool arch_try_cmpxchg128(volatile u128 *ptr, u128 *oldp, u128 new) 77{ 78 return __arch_try_cmpxchg128(ptr, oldp, new, LOCK_PREFIX); 79} 80#define arch_try_cmpxchg128 arch_try_cmpxchg128 81 82static __always_inline bool arch_try_cmpxchg128_local(volatile u128 *ptr, u128 *oldp, u128 new) 83{ 84 return __arch_try_cmpxchg128(ptr, oldp, new,); 85} 86#define arch_try_cmpxchg128_local arch_try_cmpxchg128_local 87 88#define system_has_cmpxchg128() boot_cpu_has(X86_FEATURE_CX16) 89 90#endif /* _ASM_X86_CMPXCHG_64_H */ 91