1 #ifndef _ASM_X86_STRING_64_H 2 #define _ASM_X86_STRING_64_H 3 4 #ifdef __KERNEL__ 5 #include <linux/jump_label.h> 6 7 /* Written 2002 by Andi Kleen */ 8 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) 11 { 12 unsigned long d0, d1, d2; 13 asm volatile("rep ; movsl\n\t" 14 "testb $2,%b4\n\t" 15 "je 1f\n\t" 16 "movsw\n" 17 "1:\ttestb $1,%b4\n\t" 18 "je 2f\n\t" 19 "movsb\n" 20 "2:" 21 : "=&c" (d0), "=&D" (d1), "=&S" (d2) 22 : "0" (n / 4), "q" (n), "1" ((long)to), "2" ((long)from) 23 : "memory"); 24 return to; 25 } 26 27 /* Even with __builtin_ the compiler may decide to use the out of line 28 function. */ 29 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); 33 34 #ifndef CONFIG_FORTIFY_SOURCE 35 #ifndef CONFIG_KMEMCHECK 36 #if (__GNUC__ == 4 && __GNUC_MINOR__ < 3) || __GNUC__ < 4 37 #define memcpy(dst, src, len) \ 38 ({ \ 39 size_t __len = (len); \ 40 void *__ret; \ 41 if (__builtin_constant_p(len) && __len >= 64) \ 42 __ret = __memcpy((dst), (src), __len); \ 43 else \ 44 __ret = __builtin_memcpy((dst), (src), __len); \ 45 __ret; \ 46 }) 47 #endif 48 #else 49 /* 50 * kmemcheck becomes very happy if we use the REP instructions unconditionally, 51 * because it means that we know both memory operands in advance. 52 */ 53 #define memcpy(dst, src, len) __inline_memcpy((dst), (src), (len)) 54 #endif 55 #endif /* !CONFIG_FORTIFY_SOURCE */ 56 57 #define __HAVE_ARCH_MEMSET 58 void *memset(void *s, int c, size_t n); 59 void *__memset(void *s, int c, size_t n); 60 61 #define __HAVE_ARCH_MEMMOVE 62 void *memmove(void *dest, const void *src, size_t count); 63 void *__memmove(void *dest, const void *src, size_t count); 64 65 int memcmp(const void *cs, const void *ct, size_t count); 66 size_t strlen(const char *s); 67 char *strcpy(char *dest, const char *src); 68 char *strcat(char *dest, const char *src); 69 int strcmp(const char *cs, const char *ct); 70 71 #if defined(CONFIG_KASAN) && !defined(__SANITIZE_ADDRESS__) 72 73 /* 74 * For files that not instrumented (e.g. mm/slub.c) we 75 * should use not instrumented version of mem* functions. 76 */ 77 78 #undef memcpy 79 #define memcpy(dst, src, len) __memcpy(dst, src, len) 80 #define memmove(dst, src, len) __memmove(dst, src, len) 81 #define memset(s, c, n) __memset(s, c, n) 82 83 #ifndef __NO_FORTIFY 84 #define __NO_FORTIFY /* FORTIFY_SOURCE uses __builtin_memcpy, etc. */ 85 #endif 86 87 #endif 88 89 #define __HAVE_ARCH_MEMCPY_MCSAFE 1 90 __must_check int memcpy_mcsafe_unrolled(void *dst, const void *src, size_t cnt); 91 DECLARE_STATIC_KEY_FALSE(mcsafe_key); 92 93 /** 94 * memcpy_mcsafe - copy memory with indication if a machine check happened 95 * 96 * @dst: destination address 97 * @src: source address 98 * @cnt: number of bytes to copy 99 * 100 * Low level memory copy function that catches machine checks 101 * We only call into the "safe" function on systems that can 102 * actually do machine check recovery. Everyone else can just 103 * use memcpy(). 104 * 105 * Return 0 for success, -EFAULT for fail 106 */ 107 static __always_inline __must_check int 108 memcpy_mcsafe(void *dst, const void *src, size_t cnt) 109 { 110 #ifdef CONFIG_X86_MCE 111 if (static_branch_unlikely(&mcsafe_key)) 112 return memcpy_mcsafe_unrolled(dst, src, cnt); 113 else 114 #endif 115 memcpy(dst, src, cnt); 116 return 0; 117 } 118 119 #ifdef CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE 120 #define __HAVE_ARCH_MEMCPY_FLUSHCACHE 1 121 void memcpy_flushcache(void *dst, const void *src, size_t cnt); 122 #endif 123 124 #endif /* __KERNEL__ */ 125 126 #endif /* _ASM_X86_STRING_64_H */ 127