1 #ifndef _ASM_X86_STRING_64_H
2 #define _ASM_X86_STRING_64_H
5 #include <linux/jump_label.h>
7 /* Written 2002 by Andi Kleen */
9 /* Only used for special circumstances. Stolen from i386/string.h */
10 static __always_inline void *__inline_memcpy(void *to, const void *from, size_t n)
12 unsigned long d0, d1, d2;
13 asm volatile("rep ; movsl\n\t"
17 "1:\ttestb $1,%b4\n\t"
21 : "=&c" (d0), "=&D" (d1), "=&S" (d2)
22 : "0" (n / 4), "q" (n), "1" ((long)to), "2" ((long)from)
27 /* Even with __builtin_ the compiler may decide to use the out of line
30 #define __HAVE_ARCH_MEMCPY 1
31 extern void *memcpy(void *to, const void *from, size_t len);
32 extern void *__memcpy(void *to, const void *from, size_t len);
34 #ifndef CONFIG_KMEMCHECK
35 #if (__GNUC__ == 4 && __GNUC_MINOR__ < 3) || __GNUC__ < 4
36 #define memcpy(dst, src, len) \
38 size_t __len = (len); \
40 if (__builtin_constant_p(len) && __len >= 64) \
41 __ret = __memcpy((dst), (src), __len); \
43 __ret = __builtin_memcpy((dst), (src), __len); \
49 * kmemcheck becomes very happy if we use the REP instructions unconditionally,
50 * because it means that we know both memory operands in advance.
52 #define memcpy(dst, src, len) __inline_memcpy((dst), (src), (len))
55 #define __HAVE_ARCH_MEMSET
56 void *memset(void *s, int c, size_t n);
57 void *__memset(void *s, int c, size_t n);
59 #define __HAVE_ARCH_MEMMOVE
60 void *memmove(void *dest, const void *src, size_t count);
61 void *__memmove(void *dest, const void *src, size_t count);
63 int memcmp(const void *cs, const void *ct, size_t count);
64 size_t strlen(const char *s);
65 char *strcpy(char *dest, const char *src);
66 char *strcat(char *dest, const char *src);
67 int strcmp(const char *cs, const char *ct);
69 #if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__)
72 * For files that not instrumented (e.g. mm/slub.c) we
73 * should use not instrumented version of mem* functions.
77 #define memcpy(dst, src, len) __memcpy(dst, src, len)
78 #define memmove(dst, src, len) __memmove(dst, src, len)
79 #define memset(s, c, n) __memset(s, c, n)
82 __must_check int memcpy_mcsafe_unrolled(void *dst, const void *src, size_t cnt);
83 DECLARE_STATIC_KEY_FALSE(mcsafe_key);
86 * memcpy_mcsafe - copy memory with indication if a machine check happened
88 * @dst: destination address
89 * @src: source address
90 * @cnt: number of bytes to copy
92 * Low level memory copy function that catches machine checks
93 * We only call into the "safe" function on systems that can
94 * actually do machine check recovery. Everyone else can just
97 * Return 0 for success, -EFAULT for fail
99 static __always_inline __must_check int
100 memcpy_mcsafe(void *dst, const void *src, size_t cnt)
102 #ifdef CONFIG_X86_MCE
103 if (static_branch_unlikely(&mcsafe_key))
104 return memcpy_mcsafe_unrolled(dst, src, cnt);
107 memcpy(dst, src, cnt);
111 #endif /* __KERNEL__ */
113 #endif /* _ASM_X86_STRING_64_H */