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 #ifdef CONFIG_X86_USE_3DNOW 150 151 #include <asm/mmx.h> 152 153 /* 154 * This CPU favours 3DNow strongly (eg AMD Athlon) 155 */ 156 157 static inline void *__constant_memcpy3d(void *to, const void *from, size_t len) 158 { 159 if (len < 512) 160 return __constant_memcpy(to, from, len); 161 return _mmx_memcpy(to, from, len); 162 } 163 164 static inline void *__memcpy3d(void *to, const void *from, size_t len) 165 { 166 if (len < 512) 167 return __memcpy(to, from, len); 168 return _mmx_memcpy(to, from, len); 169 } 170 171 #define memcpy(t, f, n) \ 172 (__builtin_constant_p((n)) \ 173 ? __constant_memcpy3d((t), (f), (n)) \ 174 : __memcpy3d((t), (f), (n))) 175 176 #else 177 178 /* 179 * No 3D Now! 180 */ 181 182 #if (__GNUC__ >= 4) 183 #define memcpy(t, f, n) __builtin_memcpy(t, f, n) 184 #else 185 #define memcpy(t, f, n) \ 186 (__builtin_constant_p((n)) \ 187 ? __constant_memcpy((t), (f), (n)) \ 188 : __memcpy((t), (f), (n))) 189 #endif 190 191 #endif 192 #endif /* !CONFIG_FORTIFY_SOURCE */ 193 194 #define __HAVE_ARCH_MEMMOVE 195 void *memmove(void *dest, const void *src, size_t n); 196 197 extern int memcmp(const void *, const void *, size_t); 198 #ifndef CONFIG_FORTIFY_SOURCE 199 #define memcmp __builtin_memcmp 200 #endif 201 202 #define __HAVE_ARCH_MEMCHR 203 extern void *memchr(const void *cs, int c, size_t count); 204 205 static inline void *__memset_generic(void *s, char c, size_t count) 206 { 207 int d0, d1; 208 asm volatile("rep\n\t" 209 "stosb" 210 : "=&c" (d0), "=&D" (d1) 211 : "a" (c), "1" (s), "0" (count) 212 : "memory"); 213 return s; 214 } 215 216 /* we might want to write optimized versions of these later */ 217 #define __constant_count_memset(s, c, count) __memset_generic((s), (c), (count)) 218 219 /* 220 * memset(x, 0, y) is a reasonably common thing to do, so we want to fill 221 * things 32 bits at a time even when we don't know the size of the 222 * area at compile-time.. 223 */ 224 static __always_inline 225 void *__constant_c_memset(void *s, unsigned long c, size_t count) 226 { 227 int d0, d1; 228 asm volatile("rep ; stosl\n\t" 229 "testb $2,%b3\n\t" 230 "je 1f\n\t" 231 "stosw\n" 232 "1:\ttestb $1,%b3\n\t" 233 "je 2f\n\t" 234 "stosb\n" 235 "2:" 236 : "=&c" (d0), "=&D" (d1) 237 : "a" (c), "q" (count), "0" (count/4), "1" ((long)s) 238 : "memory"); 239 return s; 240 } 241 242 /* Added by Gertjan van Wingerde to make minix and sysv module work */ 243 #define __HAVE_ARCH_STRNLEN 244 extern size_t strnlen(const char *s, size_t count); 245 /* end of additional stuff */ 246 247 #define __HAVE_ARCH_STRSTR 248 extern char *strstr(const char *cs, const char *ct); 249 250 /* 251 * This looks horribly ugly, but the compiler can optimize it totally, 252 * as we by now know that both pattern and count is constant.. 253 */ 254 static __always_inline 255 void *__constant_c_and_count_memset(void *s, unsigned long pattern, 256 size_t count) 257 { 258 switch (count) { 259 case 0: 260 return s; 261 case 1: 262 *(unsigned char *)s = pattern & 0xff; 263 return s; 264 case 2: 265 *(unsigned short *)s = pattern & 0xffff; 266 return s; 267 case 3: 268 *(unsigned short *)s = pattern & 0xffff; 269 *((unsigned char *)s + 2) = pattern & 0xff; 270 return s; 271 case 4: 272 *(unsigned long *)s = pattern; 273 return s; 274 } 275 276 #define COMMON(x) \ 277 asm volatile("rep ; stosl" \ 278 x \ 279 : "=&c" (d0), "=&D" (d1) \ 280 : "a" (eax), "0" (count/4), "1" ((long)s) \ 281 : "memory") 282 283 { 284 int d0, d1; 285 #if __GNUC__ == 4 && __GNUC_MINOR__ == 0 286 /* Workaround for broken gcc 4.0 */ 287 register unsigned long eax asm("%eax") = pattern; 288 #else 289 unsigned long eax = pattern; 290 #endif 291 292 switch (count % 4) { 293 case 0: 294 COMMON(""); 295 return s; 296 case 1: 297 COMMON("\n\tstosb"); 298 return s; 299 case 2: 300 COMMON("\n\tstosw"); 301 return s; 302 default: 303 COMMON("\n\tstosw\n\tstosb"); 304 return s; 305 } 306 } 307 308 #undef COMMON 309 } 310 311 #define __constant_c_x_memset(s, c, count) \ 312 (__builtin_constant_p(count) \ 313 ? __constant_c_and_count_memset((s), (c), (count)) \ 314 : __constant_c_memset((s), (c), (count))) 315 316 #define __memset(s, c, count) \ 317 (__builtin_constant_p(count) \ 318 ? __constant_count_memset((s), (c), (count)) \ 319 : __memset_generic((s), (c), (count))) 320 321 #define __HAVE_ARCH_MEMSET 322 extern void *memset(void *, int, size_t); 323 #ifndef CONFIG_FORTIFY_SOURCE 324 #if (__GNUC__ >= 4) 325 #define memset(s, c, count) __builtin_memset(s, c, count) 326 #else 327 #define memset(s, c, count) \ 328 (__builtin_constant_p(c) \ 329 ? __constant_c_x_memset((s), (0x01010101UL * (unsigned char)(c)), \ 330 (count)) \ 331 : __memset((s), (c), (count))) 332 #endif 333 #endif /* !CONFIG_FORTIFY_SOURCE */ 334 335 #define __HAVE_ARCH_MEMSET16 336 static inline void *memset16(uint16_t *s, uint16_t v, size_t n) 337 { 338 int d0, d1; 339 asm volatile("rep\n\t" 340 "stosw" 341 : "=&c" (d0), "=&D" (d1) 342 : "a" (v), "1" (s), "0" (n) 343 : "memory"); 344 return s; 345 } 346 347 #define __HAVE_ARCH_MEMSET32 348 static inline void *memset32(uint32_t *s, uint32_t v, size_t n) 349 { 350 int d0, d1; 351 asm volatile("rep\n\t" 352 "stosl" 353 : "=&c" (d0), "=&D" (d1) 354 : "a" (v), "1" (s), "0" (n) 355 : "memory"); 356 return s; 357 } 358 359 /* 360 * find the first occurrence of byte 'c', or 1 past the area if none 361 */ 362 #define __HAVE_ARCH_MEMSCAN 363 extern void *memscan(void *addr, int c, size_t size); 364 365 #endif /* __KERNEL__ */ 366 367 #endif /* _ASM_X86_STRING_32_H */ 368