1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef _ASM_X86_STRING_32_H 3 #define _ASM_X86_STRING_32_H 4 5 #ifdef __KERNEL__ 6 7 /* Let gcc decide whether to inline or use the out of line functions */ 8 9 #define __HAVE_ARCH_STRCPY 10 extern char *strcpy(char *dest, const char *src); 11 12 #define __HAVE_ARCH_STRNCPY 13 extern char *strncpy(char *dest, const char *src, size_t count); 14 15 #define __HAVE_ARCH_STRCAT 16 extern char *strcat(char *dest, const char *src); 17 18 #define __HAVE_ARCH_STRNCAT 19 extern char *strncat(char *dest, const char *src, size_t count); 20 21 #define __HAVE_ARCH_STRCMP 22 extern int strcmp(const char *cs, const char *ct); 23 24 #define __HAVE_ARCH_STRNCMP 25 extern int strncmp(const char *cs, const char *ct, size_t count); 26 27 #define __HAVE_ARCH_STRCHR 28 extern char *strchr(const char *s, int c); 29 30 #define __HAVE_ARCH_STRLEN 31 extern size_t strlen(const char *s); 32 33 static __always_inline void *__memcpy(void *to, const void *from, size_t n) 34 { 35 int d0, d1, d2; 36 asm volatile("rep ; movsl\n\t" 37 "movl %4,%%ecx\n\t" 38 "andl $3,%%ecx\n\t" 39 "jz 1f\n\t" 40 "rep ; movsb\n\t" 41 "1:" 42 : "=&c" (d0), "=&D" (d1), "=&S" (d2) 43 : "0" (n / 4), "g" (n), "1" ((long)to), "2" ((long)from) 44 : "memory"); 45 return to; 46 } 47 48 /* 49 * This looks ugly, but the compiler can optimize it totally, 50 * as the count is constant. 51 */ 52 static __always_inline void *__constant_memcpy(void *to, const void *from, 53 size_t n) 54 { 55 long esi, edi; 56 if (!n) 57 return to; 58 59 switch (n) { 60 case 1: 61 *(char *)to = *(char *)from; 62 return to; 63 case 2: 64 *(short *)to = *(short *)from; 65 return to; 66 case 4: 67 *(int *)to = *(int *)from; 68 return to; 69 case 3: 70 *(short *)to = *(short *)from; 71 *((char *)to + 2) = *((char *)from + 2); 72 return to; 73 case 5: 74 *(int *)to = *(int *)from; 75 *((char *)to + 4) = *((char *)from + 4); 76 return to; 77 case 6: 78 *(int *)to = *(int *)from; 79 *((short *)to + 2) = *((short *)from + 2); 80 return to; 81 case 8: 82 *(int *)to = *(int *)from; 83 *((int *)to + 1) = *((int *)from + 1); 84 return to; 85 } 86 87 esi = (long)from; 88 edi = (long)to; 89 if (n >= 5 * 4) { 90 /* large block: use rep prefix */ 91 int ecx; 92 asm volatile("rep ; movsl" 93 : "=&c" (ecx), "=&D" (edi), "=&S" (esi) 94 : "0" (n / 4), "1" (edi), "2" (esi) 95 : "memory" 96 ); 97 } else { 98 /* small block: don't clobber ecx + smaller code */ 99 if (n >= 4 * 4) 100 asm volatile("movsl" 101 : "=&D"(edi), "=&S"(esi) 102 : "0"(edi), "1"(esi) 103 : "memory"); 104 if (n >= 3 * 4) 105 asm volatile("movsl" 106 : "=&D"(edi), "=&S"(esi) 107 : "0"(edi), "1"(esi) 108 : "memory"); 109 if (n >= 2 * 4) 110 asm volatile("movsl" 111 : "=&D"(edi), "=&S"(esi) 112 : "0"(edi), "1"(esi) 113 : "memory"); 114 if (n >= 1 * 4) 115 asm volatile("movsl" 116 : "=&D"(edi), "=&S"(esi) 117 : "0"(edi), "1"(esi) 118 : "memory"); 119 } 120 switch (n % 4) { 121 /* tail */ 122 case 0: 123 return to; 124 case 1: 125 asm volatile("movsb" 126 : "=&D"(edi), "=&S"(esi) 127 : "0"(edi), "1"(esi) 128 : "memory"); 129 return to; 130 case 2: 131 asm volatile("movsw" 132 : "=&D"(edi), "=&S"(esi) 133 : "0"(edi), "1"(esi) 134 : "memory"); 135 return to; 136 default: 137 asm volatile("movsw\n\tmovsb" 138 : "=&D"(edi), "=&S"(esi) 139 : "0"(edi), "1"(esi) 140 : "memory"); 141 return to; 142 } 143 } 144 145 #define __HAVE_ARCH_MEMCPY 146 extern void *memcpy(void *, const void *, size_t); 147 148 #ifndef CONFIG_FORTIFY_SOURCE 149 150 #define memcpy(t, f, n) __builtin_memcpy(t, f, n) 151 152 #endif /* !CONFIG_FORTIFY_SOURCE */ 153 154 #define __HAVE_ARCH_MEMMOVE 155 void *memmove(void *dest, const void *src, size_t n); 156 157 extern int memcmp(const void *, const void *, size_t); 158 #ifndef CONFIG_FORTIFY_SOURCE 159 #define memcmp __builtin_memcmp 160 #endif 161 162 #define __HAVE_ARCH_MEMCHR 163 extern void *memchr(const void *cs, int c, size_t count); 164 165 static inline void *__memset_generic(void *s, char c, size_t count) 166 { 167 int d0, d1; 168 asm volatile("rep\n\t" 169 "stosb" 170 : "=&c" (d0), "=&D" (d1) 171 : "a" (c), "1" (s), "0" (count) 172 : "memory"); 173 return s; 174 } 175 176 /* we might want to write optimized versions of these later */ 177 #define __constant_count_memset(s, c, count) __memset_generic((s), (c), (count)) 178 179 /* Added by Gertjan van Wingerde to make minix and sysv module work */ 180 #define __HAVE_ARCH_STRNLEN 181 extern size_t strnlen(const char *s, size_t count); 182 /* end of additional stuff */ 183 184 #define __HAVE_ARCH_STRSTR 185 extern char *strstr(const char *cs, const char *ct); 186 187 #define __memset(s, c, count) \ 188 (__builtin_constant_p(count) \ 189 ? __constant_count_memset((s), (c), (count)) \ 190 : __memset_generic((s), (c), (count))) 191 192 #define __HAVE_ARCH_MEMSET 193 extern void *memset(void *, int, size_t); 194 #ifndef CONFIG_FORTIFY_SOURCE 195 #define memset(s, c, count) __builtin_memset(s, c, count) 196 #endif /* !CONFIG_FORTIFY_SOURCE */ 197 198 #define __HAVE_ARCH_MEMSET16 199 static inline void *memset16(uint16_t *s, uint16_t v, size_t n) 200 { 201 int d0, d1; 202 asm volatile("rep\n\t" 203 "stosw" 204 : "=&c" (d0), "=&D" (d1) 205 : "a" (v), "1" (s), "0" (n) 206 : "memory"); 207 return s; 208 } 209 210 #define __HAVE_ARCH_MEMSET32 211 static inline void *memset32(uint32_t *s, uint32_t v, size_t n) 212 { 213 int d0, d1; 214 asm volatile("rep\n\t" 215 "stosl" 216 : "=&c" (d0), "=&D" (d1) 217 : "a" (v), "1" (s), "0" (n) 218 : "memory"); 219 return s; 220 } 221 222 /* 223 * find the first occurrence of byte 'c', or 1 past the area if none 224 */ 225 #define __HAVE_ARCH_MEMSCAN 226 extern void *memscan(void *addr, int c, size_t size); 227 228 #endif /* __KERNEL__ */ 229 230 #endif /* _ASM_X86_STRING_32_H */ 231