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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 | // SPDX-License-Identifier: GPL-2.0 /* * User address space access functions. * The non inlined parts of asm-i386/uaccess.h are here. * * Copyright 1997 Andi Kleen <ak@muc.de> * Copyright 1997 Linus Torvalds */ #include <linux/export.h> #include <linux/uaccess.h> #include <asm/asm.h> #ifdef CONFIG_X86_INTEL_USERCOPY /* * Alignment at which movsl is preferred for bulk memory copies. */ struct movsl_mask movsl_mask __read_mostly; #endif static inline int __movsl_is_ok(unsigned long a1, unsigned long a2, unsigned long n) { #ifdef CONFIG_X86_INTEL_USERCOPY if (n >= 64 && ((a1 ^ a2) & movsl_mask.mask)) return 0; #endif return 1; } #define movsl_is_ok(a1, a2, n) \ __movsl_is_ok((unsigned long)(a1), (unsigned long)(a2), (n)) /* * Zero Userspace */ #define __do_clear_user(addr,size) \ do { \ int __d0; \ might_fault(); \ __asm__ __volatile__( \ ASM_STAC "\n" \ "0: rep; stosl\n" \ " movl %2,%0\n" \ "1: rep; stosb\n" \ "2: " ASM_CLAC "\n" \ _ASM_EXTABLE_TYPE_REG(0b, 2b, EX_TYPE_UCOPY_LEN4, %2) \ _ASM_EXTABLE_UA(1b, 2b) \ : "=&c"(size), "=&D" (__d0) \ : "r"(size & 3), "0"(size / 4), "1"(addr), "a"(0)); \ } while (0) /** * clear_user - Zero a block of memory in user space. * @to: Destination address, in user space. * @n: Number of bytes to zero. * * Zero a block of memory in user space. * * Return: number of bytes that could not be cleared. * On success, this will be zero. */ unsigned long clear_user(void __user *to, unsigned long n) { might_fault(); if (access_ok(to, n)) __do_clear_user(to, n); return n; } EXPORT_SYMBOL(clear_user); /** * __clear_user - Zero a block of memory in user space, with less checking. * @to: Destination address, in user space. * @n: Number of bytes to zero. * * Zero a block of memory in user space. Caller must check * the specified block with access_ok() before calling this function. * * Return: number of bytes that could not be cleared. * On success, this will be zero. */ unsigned long __clear_user(void __user *to, unsigned long n) { __do_clear_user(to, n); return n; } EXPORT_SYMBOL(__clear_user); #ifdef CONFIG_X86_INTEL_USERCOPY static unsigned long __copy_user_intel(void __user *to, const void *from, unsigned long size) { int d0, d1; __asm__ __volatile__( " .align 2,0x90\n" "1: movl 32(%4), %%eax\n" " cmpl $67, %0\n" " jbe 3f\n" "2: movl 64(%4), %%eax\n" " .align 2,0x90\n" "3: movl 0(%4), %%eax\n" "4: movl 4(%4), %%edx\n" "5: movl %%eax, 0(%3)\n" "6: movl %%edx, 4(%3)\n" "7: movl 8(%4), %%eax\n" "8: movl 12(%4),%%edx\n" "9: movl %%eax, 8(%3)\n" "10: movl %%edx, 12(%3)\n" "11: movl 16(%4), %%eax\n" "12: movl 20(%4), %%edx\n" "13: movl %%eax, 16(%3)\n" "14: movl %%edx, 20(%3)\n" "15: movl 24(%4), %%eax\n" "16: movl 28(%4), %%edx\n" "17: movl %%eax, 24(%3)\n" "18: movl %%edx, 28(%3)\n" "19: movl 32(%4), %%eax\n" "20: movl 36(%4), %%edx\n" "21: movl %%eax, 32(%3)\n" "22: movl %%edx, 36(%3)\n" "23: movl 40(%4), %%eax\n" "24: movl 44(%4), %%edx\n" "25: movl %%eax, 40(%3)\n" "26: movl %%edx, 44(%3)\n" "27: movl 48(%4), %%eax\n" "28: movl 52(%4), %%edx\n" "29: movl %%eax, 48(%3)\n" "30: movl %%edx, 52(%3)\n" "31: movl 56(%4), %%eax\n" "32: movl 60(%4), %%edx\n" "33: movl %%eax, 56(%3)\n" "34: movl %%edx, 60(%3)\n" " addl $-64, %0\n" " addl $64, %4\n" " addl $64, %3\n" " cmpl $63, %0\n" " ja 1b\n" "35: movl %0, %%eax\n" " shrl $2, %0\n" " andl $3, %%eax\n" " cld\n" "99: rep; movsl\n" "36: movl %%eax, %0\n" "37: rep; movsb\n" "100:\n" _ASM_EXTABLE_UA(1b, 100b) _ASM_EXTABLE_UA(2b, 100b) _ASM_EXTABLE_UA(3b, 100b) _ASM_EXTABLE_UA(4b, 100b) _ASM_EXTABLE_UA(5b, 100b) _ASM_EXTABLE_UA(6b, 100b) _ASM_EXTABLE_UA(7b, 100b) _ASM_EXTABLE_UA(8b, 100b) _ASM_EXTABLE_UA(9b, 100b) _ASM_EXTABLE_UA(10b, 100b) _ASM_EXTABLE_UA(11b, 100b) _ASM_EXTABLE_UA(12b, 100b) _ASM_EXTABLE_UA(13b, 100b) _ASM_EXTABLE_UA(14b, 100b) _ASM_EXTABLE_UA(15b, 100b) _ASM_EXTABLE_UA(16b, 100b) _ASM_EXTABLE_UA(17b, 100b) _ASM_EXTABLE_UA(18b, 100b) _ASM_EXTABLE_UA(19b, 100b) _ASM_EXTABLE_UA(20b, 100b) _ASM_EXTABLE_UA(21b, 100b) _ASM_EXTABLE_UA(22b, 100b) _ASM_EXTABLE_UA(23b, 100b) _ASM_EXTABLE_UA(24b, 100b) _ASM_EXTABLE_UA(25b, 100b) _ASM_EXTABLE_UA(26b, 100b) _ASM_EXTABLE_UA(27b, 100b) _ASM_EXTABLE_UA(28b, 100b) _ASM_EXTABLE_UA(29b, 100b) _ASM_EXTABLE_UA(30b, 100b) _ASM_EXTABLE_UA(31b, 100b) _ASM_EXTABLE_UA(32b, 100b) _ASM_EXTABLE_UA(33b, 100b) _ASM_EXTABLE_UA(34b, 100b) _ASM_EXTABLE_UA(35b, 100b) _ASM_EXTABLE_UA(36b, 100b) _ASM_EXTABLE_UA(37b, 100b) _ASM_EXTABLE_TYPE_REG(99b, 100b, EX_TYPE_UCOPY_LEN4, %%eax) : "=&c"(size), "=&D" (d0), "=&S" (d1) : "1"(to), "2"(from), "0"(size) : "eax", "edx", "memory"); return size; } static unsigned long __copy_user_intel_nocache(void *to, const void __user *from, unsigned long size) { int d0, d1; __asm__ __volatile__( " .align 2,0x90\n" "0: movl 32(%4), %%eax\n" " cmpl $67, %0\n" " jbe 2f\n" "1: movl 64(%4), %%eax\n" " .align 2,0x90\n" "2: movl 0(%4), %%eax\n" "21: movl 4(%4), %%edx\n" " movnti %%eax, 0(%3)\n" " movnti %%edx, 4(%3)\n" "3: movl 8(%4), %%eax\n" "31: movl 12(%4),%%edx\n" " movnti %%eax, 8(%3)\n" " movnti %%edx, 12(%3)\n" "4: movl 16(%4), %%eax\n" "41: movl 20(%4), %%edx\n" " movnti %%eax, 16(%3)\n" " movnti %%edx, 20(%3)\n" "10: movl 24(%4), %%eax\n" "51: movl 28(%4), %%edx\n" " movnti %%eax, 24(%3)\n" " movnti %%edx, 28(%3)\n" "11: movl 32(%4), %%eax\n" "61: movl 36(%4), %%edx\n" " movnti %%eax, 32(%3)\n" " movnti %%edx, 36(%3)\n" "12: movl 40(%4), %%eax\n" "71: movl 44(%4), %%edx\n" " movnti %%eax, 40(%3)\n" " movnti %%edx, 44(%3)\n" "13: movl 48(%4), %%eax\n" "81: movl 52(%4), %%edx\n" " movnti %%eax, 48(%3)\n" " movnti %%edx, 52(%3)\n" "14: movl 56(%4), %%eax\n" "91: movl 60(%4), %%edx\n" " movnti %%eax, 56(%3)\n" " movnti %%edx, 60(%3)\n" " addl $-64, %0\n" " addl $64, %4\n" " addl $64, %3\n" " cmpl $63, %0\n" " ja 0b\n" " sfence \n" "5: movl %0, %%eax\n" " shrl $2, %0\n" " andl $3, %%eax\n" " cld\n" "6: rep; movsl\n" " movl %%eax,%0\n" "7: rep; movsb\n" "8:\n" _ASM_EXTABLE_UA(0b, 8b) _ASM_EXTABLE_UA(1b, 8b) _ASM_EXTABLE_UA(2b, 8b) _ASM_EXTABLE_UA(21b, 8b) _ASM_EXTABLE_UA(3b, 8b) _ASM_EXTABLE_UA(31b, 8b) _ASM_EXTABLE_UA(4b, 8b) _ASM_EXTABLE_UA(41b, 8b) _ASM_EXTABLE_UA(10b, 8b) _ASM_EXTABLE_UA(51b, 8b) _ASM_EXTABLE_UA(11b, 8b) _ASM_EXTABLE_UA(61b, 8b) _ASM_EXTABLE_UA(12b, 8b) _ASM_EXTABLE_UA(71b, 8b) _ASM_EXTABLE_UA(13b, 8b) _ASM_EXTABLE_UA(81b, 8b) _ASM_EXTABLE_UA(14b, 8b) _ASM_EXTABLE_UA(91b, 8b) _ASM_EXTABLE_TYPE_REG(6b, 8b, EX_TYPE_UCOPY_LEN4, %%eax) _ASM_EXTABLE_UA(7b, 8b) : "=&c"(size), "=&D" (d0), "=&S" (d1) : "1"(to), "2"(from), "0"(size) : "eax", "edx", "memory"); return size; } #else /* * Leave these declared but undefined. They should not be any references to * them */ unsigned long __copy_user_intel(void __user *to, const void *from, unsigned long size); #endif /* CONFIG_X86_INTEL_USERCOPY */ /* Generic arbitrary sized copy. */ #define __copy_user(to, from, size) \ do { \ int __d0, __d1, __d2; \ __asm__ __volatile__( \ " cmp $7,%0\n" \ " jbe 1f\n" \ " movl %1,%0\n" \ " negl %0\n" \ " andl $7,%0\n" \ " subl %0,%3\n" \ "4: rep; movsb\n" \ " movl %3,%0\n" \ " shrl $2,%0\n" \ " andl $3,%3\n" \ " .align 2,0x90\n" \ "0: rep; movsl\n" \ " movl %3,%0\n" \ "1: rep; movsb\n" \ "2:\n" \ _ASM_EXTABLE_TYPE_REG(4b, 2b, EX_TYPE_UCOPY_LEN1, %3) \ _ASM_EXTABLE_TYPE_REG(0b, 2b, EX_TYPE_UCOPY_LEN4, %3) \ _ASM_EXTABLE_UA(1b, 2b) \ : "=&c"(size), "=&D" (__d0), "=&S" (__d1), "=r"(__d2) \ : "3"(size), "0"(size), "1"(to), "2"(from) \ : "memory"); \ } while (0) unsigned long __copy_user_ll(void *to, const void *from, unsigned long n) { __uaccess_begin_nospec(); if (movsl_is_ok(to, from, n)) __copy_user(to, from, n); else n = __copy_user_intel(to, from, n); __uaccess_end(); return n; } EXPORT_SYMBOL(__copy_user_ll); unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from, unsigned long n) { __uaccess_begin_nospec(); #ifdef CONFIG_X86_INTEL_USERCOPY if (n > 64 && static_cpu_has(X86_FEATURE_XMM2)) n = __copy_user_intel_nocache(to, from, n); else __copy_user(to, from, n); #else __copy_user(to, from, n); #endif __uaccess_end(); return n; } EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero); |