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
23 union __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
arch_cmpxchg128(volatile u128 * ptr,u128 old,u128 new)44 static __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
arch_cmpxchg128_local(volatile u128 * ptr,u128 old,u128 new)50 static __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
arch_try_cmpxchg128(volatile u128 * ptr,u128 * oldp,u128 new)76 static __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
arch_try_cmpxchg128_local(volatile u128 * ptr,u128 * oldp,u128 new)82 static __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