Linux kernel mirror (for testing)
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_STRING_64_H
3#define _ASM_X86_STRING_64_H
4
5#ifdef __KERNEL__
6#include <linux/jump_label.h>
7
8/* Written 2002 by Andi Kleen */
9
10/* Even with __builtin_ the compiler may decide to use the out of line
11 function. */
12
13#define __HAVE_ARCH_MEMCPY 1
14extern void *memcpy(void *to, const void *from, size_t len);
15extern void *__memcpy(void *to, const void *from, size_t len);
16
17#define __HAVE_ARCH_MEMSET
18void *memset(void *s, int c, size_t n);
19void *__memset(void *s, int c, size_t n);
20
21#define __HAVE_ARCH_MEMSET16
22static inline void *memset16(uint16_t *s, uint16_t v, size_t n)
23{
24 long d0, d1;
25 asm volatile("rep\n\t"
26 "stosw"
27 : "=&c" (d0), "=&D" (d1)
28 : "a" (v), "1" (s), "0" (n)
29 : "memory");
30 return s;
31}
32
33#define __HAVE_ARCH_MEMSET32
34static inline void *memset32(uint32_t *s, uint32_t v, size_t n)
35{
36 long d0, d1;
37 asm volatile("rep\n\t"
38 "stosl"
39 : "=&c" (d0), "=&D" (d1)
40 : "a" (v), "1" (s), "0" (n)
41 : "memory");
42 return s;
43}
44
45#define __HAVE_ARCH_MEMSET64
46static inline void *memset64(uint64_t *s, uint64_t v, size_t n)
47{
48 long d0, d1;
49 asm volatile("rep\n\t"
50 "stosq"
51 : "=&c" (d0), "=&D" (d1)
52 : "a" (v), "1" (s), "0" (n)
53 : "memory");
54 return s;
55}
56
57#define __HAVE_ARCH_MEMMOVE
58void *memmove(void *dest, const void *src, size_t count);
59void *__memmove(void *dest, const void *src, size_t count);
60
61int memcmp(const void *cs, const void *ct, size_t count);
62size_t strlen(const char *s);
63char *strcpy(char *dest, const char *src);
64char *strcat(char *dest, const char *src);
65int strcmp(const char *cs, const char *ct);
66
67#if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__)
68
69/*
70 * For files that not instrumented (e.g. mm/slub.c) we
71 * should use not instrumented version of mem* functions.
72 */
73
74#undef memcpy
75#define memcpy(dst, src, len) __memcpy(dst, src, len)
76#define memmove(dst, src, len) __memmove(dst, src, len)
77#define memset(s, c, n) __memset(s, c, n)
78
79#ifndef __NO_FORTIFY
80#define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */
81#endif
82
83#endif
84
85#define __HAVE_ARCH_MEMCPY_MCSAFE 1
86__must_check unsigned long __memcpy_mcsafe(void *dst, const void *src,
87 size_t cnt);
88DECLARE_STATIC_KEY_FALSE(mcsafe_key);
89
90/**
91 * memcpy_mcsafe - copy memory with indication if a machine check happened
92 *
93 * @dst: destination address
94 * @src: source address
95 * @cnt: number of bytes to copy
96 *
97 * Low level memory copy function that catches machine checks
98 * We only call into the "safe" function on systems that can
99 * actually do machine check recovery. Everyone else can just
100 * use memcpy().
101 *
102 * Return 0 for success, or number of bytes not copied if there was an
103 * exception.
104 */
105static __always_inline __must_check unsigned long
106memcpy_mcsafe(void *dst, const void *src, size_t cnt)
107{
108#ifdef CONFIG_X86_MCE
109 if (static_branch_unlikely(&mcsafe_key))
110 return __memcpy_mcsafe(dst, src, cnt);
111 else
112#endif
113 memcpy(dst, src, cnt);
114 return 0;
115}
116
117#ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE
118#define __HAVE_ARCH_MEMCPY_FLUSHCACHE 1
119void __memcpy_flushcache(void *dst, const void *src, size_t cnt);
120static __always_inline void memcpy_flushcache(void *dst, const void *src, size_t cnt)
121{
122 if (__builtin_constant_p(cnt)) {
123 switch (cnt) {
124 case 4:
125 asm ("movntil %1, %0" : "=m"(*(u32 *)dst) : "r"(*(u32 *)src));
126 return;
127 case 8:
128 asm ("movntiq %1, %0" : "=m"(*(u64 *)dst) : "r"(*(u64 *)src));
129 return;
130 case 16:
131 asm ("movntiq %1, %0" : "=m"(*(u64 *)dst) : "r"(*(u64 *)src));
132 asm ("movntiq %1, %0" : "=m"(*(u64 *)(dst + 8)) : "r"(*(u64 *)(src + 8)));
133 return;
134 }
135 }
136 __memcpy_flushcache(dst, src, cnt);
137}
138#endif
139
140#endif /* __KERNEL__ */
141
142#endif /* _ASM_X86_STRING_64_H */