1 /* 2 * Handle unaligned accesses by emulation. 3 * 4 * This file is subject to the terms and conditions of the GNU General Public 5 * License. See the file "COPYING" in the main directory of this archive 6 * for more details. 7 * 8 * Copyright (C) 1996, 1998, 1999, 2002 by Ralf Baechle 9 * Copyright (C) 1999 Silicon Graphics, Inc. 10 * Copyright (C) 2014 Imagination Technologies Ltd. 11 * 12 * This file contains exception handler for address error exception with the 13 * special capability to execute faulting instructions in software. The 14 * handler does not try to handle the case when the program counter points 15 * to an address not aligned to a word boundary. 16 * 17 * Putting data to unaligned addresses is a bad practice even on Intel where 18 * only the performance is affected. Much worse is that such code is non- 19 * portable. Due to several programs that die on MIPS due to alignment 20 * problems I decided to implement this handler anyway though I originally 21 * didn't intend to do this at all for user code. 22 * 23 * For now I enable fixing of address errors by default to make life easier. 24 * I however intend to disable this somewhen in the future when the alignment 25 * problems with user programs have been fixed. For programmers this is the 26 * right way to go. 27 * 28 * Fixing address errors is a per process option. The option is inherited 29 * across fork(2) and execve(2) calls. If you really want to use the 30 * option in your user programs - I discourage the use of the software 31 * emulation strongly - use the following code in your userland stuff: 32 * 33 * #include <sys/sysmips.h> 34 * 35 * ... 36 * sysmips(MIPS_FIXADE, x); 37 * ... 38 * 39 * The argument x is 0 for disabling software emulation, enabled otherwise. 40 * 41 * Below a little program to play around with this feature. 42 * 43 * #include <stdio.h> 44 * #include <sys/sysmips.h> 45 * 46 * struct foo { 47 * unsigned char bar[8]; 48 * }; 49 * 50 * main(int argc, char *argv[]) 51 * { 52 * struct foo x = {0, 1, 2, 3, 4, 5, 6, 7}; 53 * unsigned int *p = (unsigned int *) (x.bar + 3); 54 * int i; 55 * 56 * if (argc > 1) 57 * sysmips(MIPS_FIXADE, atoi(argv[1])); 58 * 59 * printf("*p = %08lx\n", *p); 60 * 61 * *p = 0xdeadface; 62 * 63 * for(i = 0; i <= 7; i++) 64 * printf("%02x ", x.bar[i]); 65 * printf("\n"); 66 * } 67 * 68 * Coprocessor loads are not supported; I think this case is unimportant 69 * in the practice. 70 * 71 * TODO: Handle ndc (attempted store to doubleword in uncached memory) 72 * exception for the R6000. 73 * A store crossing a page boundary might be executed only partially. 74 * Undo the partial store in this case. 75 */ 76 #include <linux/context_tracking.h> 77 #include <linux/mm.h> 78 #include <linux/signal.h> 79 #include <linux/smp.h> 80 #include <linux/sched.h> 81 #include <linux/debugfs.h> 82 #include <linux/perf_event.h> 83 84 #include <asm/asm.h> 85 #include <asm/branch.h> 86 #include <asm/byteorder.h> 87 #include <asm/cop2.h> 88 #include <asm/debug.h> 89 #include <asm/fpu.h> 90 #include <asm/fpu_emulator.h> 91 #include <asm/inst.h> 92 #include <asm/uaccess.h> 93 94 #define STR(x) __STR(x) 95 #define __STR(x) #x 96 97 enum { 98 UNALIGNED_ACTION_QUIET, 99 UNALIGNED_ACTION_SIGNAL, 100 UNALIGNED_ACTION_SHOW, 101 }; 102 #ifdef CONFIG_DEBUG_FS 103 static u32 unaligned_instructions; 104 static u32 unaligned_action; 105 #else 106 #define unaligned_action UNALIGNED_ACTION_QUIET 107 #endif 108 extern void show_registers(struct pt_regs *regs); 109 110 #ifdef __BIG_ENDIAN 111 #define _LoadHW(addr, value, res, type) \ 112 do { \ 113 __asm__ __volatile__ (".set\tnoat\n" \ 114 "1:\t"type##_lb("%0", "0(%2)")"\n" \ 115 "2:\t"type##_lbu("$1", "1(%2)")"\n\t"\ 116 "sll\t%0, 0x8\n\t" \ 117 "or\t%0, $1\n\t" \ 118 "li\t%1, 0\n" \ 119 "3:\t.set\tat\n\t" \ 120 ".insn\n\t" \ 121 ".section\t.fixup,\"ax\"\n\t" \ 122 "4:\tli\t%1, %3\n\t" \ 123 "j\t3b\n\t" \ 124 ".previous\n\t" \ 125 ".section\t__ex_table,\"a\"\n\t" \ 126 STR(PTR)"\t1b, 4b\n\t" \ 127 STR(PTR)"\t2b, 4b\n\t" \ 128 ".previous" \ 129 : "=&r" (value), "=r" (res) \ 130 : "r" (addr), "i" (-EFAULT)); \ 131 } while(0) 132 133 #ifndef CONFIG_CPU_MIPSR6 134 #define _LoadW(addr, value, res, type) \ 135 do { \ 136 __asm__ __volatile__ ( \ 137 "1:\t"type##_lwl("%0", "(%2)")"\n" \ 138 "2:\t"type##_lwr("%0", "3(%2)")"\n\t"\ 139 "li\t%1, 0\n" \ 140 "3:\n\t" \ 141 ".insn\n\t" \ 142 ".section\t.fixup,\"ax\"\n\t" \ 143 "4:\tli\t%1, %3\n\t" \ 144 "j\t3b\n\t" \ 145 ".previous\n\t" \ 146 ".section\t__ex_table,\"a\"\n\t" \ 147 STR(PTR)"\t1b, 4b\n\t" \ 148 STR(PTR)"\t2b, 4b\n\t" \ 149 ".previous" \ 150 : "=&r" (value), "=r" (res) \ 151 : "r" (addr), "i" (-EFAULT)); \ 152 } while(0) 153 154 #else 155 /* MIPSR6 has no lwl instruction */ 156 #define _LoadW(addr, value, res, type) \ 157 do { \ 158 __asm__ __volatile__ ( \ 159 ".set\tpush\n" \ 160 ".set\tnoat\n\t" \ 161 "1:"type##_lb("%0", "0(%2)")"\n\t" \ 162 "2:"type##_lbu("$1", "1(%2)")"\n\t" \ 163 "sll\t%0, 0x8\n\t" \ 164 "or\t%0, $1\n\t" \ 165 "3:"type##_lbu("$1", "2(%2)")"\n\t" \ 166 "sll\t%0, 0x8\n\t" \ 167 "or\t%0, $1\n\t" \ 168 "4:"type##_lbu("$1", "3(%2)")"\n\t" \ 169 "sll\t%0, 0x8\n\t" \ 170 "or\t%0, $1\n\t" \ 171 "li\t%1, 0\n" \ 172 ".set\tpop\n" \ 173 "10:\n\t" \ 174 ".insn\n\t" \ 175 ".section\t.fixup,\"ax\"\n\t" \ 176 "11:\tli\t%1, %3\n\t" \ 177 "j\t10b\n\t" \ 178 ".previous\n\t" \ 179 ".section\t__ex_table,\"a\"\n\t" \ 180 STR(PTR)"\t1b, 11b\n\t" \ 181 STR(PTR)"\t2b, 11b\n\t" \ 182 STR(PTR)"\t3b, 11b\n\t" \ 183 STR(PTR)"\t4b, 11b\n\t" \ 184 ".previous" \ 185 : "=&r" (value), "=r" (res) \ 186 : "r" (addr), "i" (-EFAULT)); \ 187 } while(0) 188 189 #endif /* CONFIG_CPU_MIPSR6 */ 190 191 #define _LoadHWU(addr, value, res, type) \ 192 do { \ 193 __asm__ __volatile__ ( \ 194 ".set\tnoat\n" \ 195 "1:\t"type##_lbu("%0", "0(%2)")"\n" \ 196 "2:\t"type##_lbu("$1", "1(%2)")"\n\t"\ 197 "sll\t%0, 0x8\n\t" \ 198 "or\t%0, $1\n\t" \ 199 "li\t%1, 0\n" \ 200 "3:\n\t" \ 201 ".insn\n\t" \ 202 ".set\tat\n\t" \ 203 ".section\t.fixup,\"ax\"\n\t" \ 204 "4:\tli\t%1, %3\n\t" \ 205 "j\t3b\n\t" \ 206 ".previous\n\t" \ 207 ".section\t__ex_table,\"a\"\n\t" \ 208 STR(PTR)"\t1b, 4b\n\t" \ 209 STR(PTR)"\t2b, 4b\n\t" \ 210 ".previous" \ 211 : "=&r" (value), "=r" (res) \ 212 : "r" (addr), "i" (-EFAULT)); \ 213 } while(0) 214 215 #ifndef CONFIG_CPU_MIPSR6 216 #define _LoadWU(addr, value, res, type) \ 217 do { \ 218 __asm__ __volatile__ ( \ 219 "1:\t"type##_lwl("%0", "(%2)")"\n" \ 220 "2:\t"type##_lwr("%0", "3(%2)")"\n\t"\ 221 "dsll\t%0, %0, 32\n\t" \ 222 "dsrl\t%0, %0, 32\n\t" \ 223 "li\t%1, 0\n" \ 224 "3:\n\t" \ 225 ".insn\n\t" \ 226 "\t.section\t.fixup,\"ax\"\n\t" \ 227 "4:\tli\t%1, %3\n\t" \ 228 "j\t3b\n\t" \ 229 ".previous\n\t" \ 230 ".section\t__ex_table,\"a\"\n\t" \ 231 STR(PTR)"\t1b, 4b\n\t" \ 232 STR(PTR)"\t2b, 4b\n\t" \ 233 ".previous" \ 234 : "=&r" (value), "=r" (res) \ 235 : "r" (addr), "i" (-EFAULT)); \ 236 } while(0) 237 238 #define _LoadDW(addr, value, res) \ 239 do { \ 240 __asm__ __volatile__ ( \ 241 "1:\tldl\t%0, (%2)\n" \ 242 "2:\tldr\t%0, 7(%2)\n\t" \ 243 "li\t%1, 0\n" \ 244 "3:\n\t" \ 245 ".insn\n\t" \ 246 "\t.section\t.fixup,\"ax\"\n\t" \ 247 "4:\tli\t%1, %3\n\t" \ 248 "j\t3b\n\t" \ 249 ".previous\n\t" \ 250 ".section\t__ex_table,\"a\"\n\t" \ 251 STR(PTR)"\t1b, 4b\n\t" \ 252 STR(PTR)"\t2b, 4b\n\t" \ 253 ".previous" \ 254 : "=&r" (value), "=r" (res) \ 255 : "r" (addr), "i" (-EFAULT)); \ 256 } while(0) 257 258 #else 259 /* MIPSR6 has not lwl and ldl instructions */ 260 #define _LoadWU(addr, value, res, type) \ 261 do { \ 262 __asm__ __volatile__ ( \ 263 ".set\tpush\n\t" \ 264 ".set\tnoat\n\t" \ 265 "1:"type##_lbu("%0", "0(%2)")"\n\t" \ 266 "2:"type##_lbu("$1", "1(%2)")"\n\t" \ 267 "sll\t%0, 0x8\n\t" \ 268 "or\t%0, $1\n\t" \ 269 "3:"type##_lbu("$1", "2(%2)")"\n\t" \ 270 "sll\t%0, 0x8\n\t" \ 271 "or\t%0, $1\n\t" \ 272 "4:"type##_lbu("$1", "3(%2)")"\n\t" \ 273 "sll\t%0, 0x8\n\t" \ 274 "or\t%0, $1\n\t" \ 275 "li\t%1, 0\n" \ 276 ".set\tpop\n" \ 277 "10:\n\t" \ 278 ".insn\n\t" \ 279 ".section\t.fixup,\"ax\"\n\t" \ 280 "11:\tli\t%1, %3\n\t" \ 281 "j\t10b\n\t" \ 282 ".previous\n\t" \ 283 ".section\t__ex_table,\"a\"\n\t" \ 284 STR(PTR)"\t1b, 11b\n\t" \ 285 STR(PTR)"\t2b, 11b\n\t" \ 286 STR(PTR)"\t3b, 11b\n\t" \ 287 STR(PTR)"\t4b, 11b\n\t" \ 288 ".previous" \ 289 : "=&r" (value), "=r" (res) \ 290 : "r" (addr), "i" (-EFAULT)); \ 291 } while(0) 292 293 #define _LoadDW(addr, value, res) \ 294 do { \ 295 __asm__ __volatile__ ( \ 296 ".set\tpush\n\t" \ 297 ".set\tnoat\n\t" \ 298 "1:lb\t%0, 0(%2)\n\t" \ 299 "2:lbu\t $1, 1(%2)\n\t" \ 300 "dsll\t%0, 0x8\n\t" \ 301 "or\t%0, $1\n\t" \ 302 "3:lbu\t$1, 2(%2)\n\t" \ 303 "dsll\t%0, 0x8\n\t" \ 304 "or\t%0, $1\n\t" \ 305 "4:lbu\t$1, 3(%2)\n\t" \ 306 "dsll\t%0, 0x8\n\t" \ 307 "or\t%0, $1\n\t" \ 308 "5:lbu\t$1, 4(%2)\n\t" \ 309 "dsll\t%0, 0x8\n\t" \ 310 "or\t%0, $1\n\t" \ 311 "6:lbu\t$1, 5(%2)\n\t" \ 312 "dsll\t%0, 0x8\n\t" \ 313 "or\t%0, $1\n\t" \ 314 "7:lbu\t$1, 6(%2)\n\t" \ 315 "dsll\t%0, 0x8\n\t" \ 316 "or\t%0, $1\n\t" \ 317 "8:lbu\t$1, 7(%2)\n\t" \ 318 "dsll\t%0, 0x8\n\t" \ 319 "or\t%0, $1\n\t" \ 320 "li\t%1, 0\n" \ 321 ".set\tpop\n\t" \ 322 "10:\n\t" \ 323 ".insn\n\t" \ 324 ".section\t.fixup,\"ax\"\n\t" \ 325 "11:\tli\t%1, %3\n\t" \ 326 "j\t10b\n\t" \ 327 ".previous\n\t" \ 328 ".section\t__ex_table,\"a\"\n\t" \ 329 STR(PTR)"\t1b, 11b\n\t" \ 330 STR(PTR)"\t2b, 11b\n\t" \ 331 STR(PTR)"\t3b, 11b\n\t" \ 332 STR(PTR)"\t4b, 11b\n\t" \ 333 STR(PTR)"\t5b, 11b\n\t" \ 334 STR(PTR)"\t6b, 11b\n\t" \ 335 STR(PTR)"\t7b, 11b\n\t" \ 336 STR(PTR)"\t8b, 11b\n\t" \ 337 ".previous" \ 338 : "=&r" (value), "=r" (res) \ 339 : "r" (addr), "i" (-EFAULT)); \ 340 } while(0) 341 342 #endif /* CONFIG_CPU_MIPSR6 */ 343 344 345 #define _StoreHW(addr, value, res, type) \ 346 do { \ 347 __asm__ __volatile__ ( \ 348 ".set\tnoat\n" \ 349 "1:\t"type##_sb("%1", "1(%2)")"\n" \ 350 "srl\t$1, %1, 0x8\n" \ 351 "2:\t"type##_sb("$1", "0(%2)")"\n" \ 352 ".set\tat\n\t" \ 353 "li\t%0, 0\n" \ 354 "3:\n\t" \ 355 ".insn\n\t" \ 356 ".section\t.fixup,\"ax\"\n\t" \ 357 "4:\tli\t%0, %3\n\t" \ 358 "j\t3b\n\t" \ 359 ".previous\n\t" \ 360 ".section\t__ex_table,\"a\"\n\t" \ 361 STR(PTR)"\t1b, 4b\n\t" \ 362 STR(PTR)"\t2b, 4b\n\t" \ 363 ".previous" \ 364 : "=r" (res) \ 365 : "r" (value), "r" (addr), "i" (-EFAULT));\ 366 } while(0) 367 368 #ifndef CONFIG_CPU_MIPSR6 369 #define _StoreW(addr, value, res, type) \ 370 do { \ 371 __asm__ __volatile__ ( \ 372 "1:\t"type##_swl("%1", "(%2)")"\n" \ 373 "2:\t"type##_swr("%1", "3(%2)")"\n\t"\ 374 "li\t%0, 0\n" \ 375 "3:\n\t" \ 376 ".insn\n\t" \ 377 ".section\t.fixup,\"ax\"\n\t" \ 378 "4:\tli\t%0, %3\n\t" \ 379 "j\t3b\n\t" \ 380 ".previous\n\t" \ 381 ".section\t__ex_table,\"a\"\n\t" \ 382 STR(PTR)"\t1b, 4b\n\t" \ 383 STR(PTR)"\t2b, 4b\n\t" \ 384 ".previous" \ 385 : "=r" (res) \ 386 : "r" (value), "r" (addr), "i" (-EFAULT)); \ 387 } while(0) 388 389 #define _StoreDW(addr, value, res) \ 390 do { \ 391 __asm__ __volatile__ ( \ 392 "1:\tsdl\t%1,(%2)\n" \ 393 "2:\tsdr\t%1, 7(%2)\n\t" \ 394 "li\t%0, 0\n" \ 395 "3:\n\t" \ 396 ".insn\n\t" \ 397 ".section\t.fixup,\"ax\"\n\t" \ 398 "4:\tli\t%0, %3\n\t" \ 399 "j\t3b\n\t" \ 400 ".previous\n\t" \ 401 ".section\t__ex_table,\"a\"\n\t" \ 402 STR(PTR)"\t1b, 4b\n\t" \ 403 STR(PTR)"\t2b, 4b\n\t" \ 404 ".previous" \ 405 : "=r" (res) \ 406 : "r" (value), "r" (addr), "i" (-EFAULT)); \ 407 } while(0) 408 409 #else 410 /* MIPSR6 has no swl and sdl instructions */ 411 #define _StoreW(addr, value, res, type) \ 412 do { \ 413 __asm__ __volatile__ ( \ 414 ".set\tpush\n\t" \ 415 ".set\tnoat\n\t" \ 416 "1:"type##_sb("%1", "3(%2)")"\n\t" \ 417 "srl\t$1, %1, 0x8\n\t" \ 418 "2:"type##_sb("$1", "2(%2)")"\n\t" \ 419 "srl\t$1, $1, 0x8\n\t" \ 420 "3:"type##_sb("$1", "1(%2)")"\n\t" \ 421 "srl\t$1, $1, 0x8\n\t" \ 422 "4:"type##_sb("$1", "0(%2)")"\n\t" \ 423 ".set\tpop\n\t" \ 424 "li\t%0, 0\n" \ 425 "10:\n\t" \ 426 ".insn\n\t" \ 427 ".section\t.fixup,\"ax\"\n\t" \ 428 "11:\tli\t%0, %3\n\t" \ 429 "j\t10b\n\t" \ 430 ".previous\n\t" \ 431 ".section\t__ex_table,\"a\"\n\t" \ 432 STR(PTR)"\t1b, 11b\n\t" \ 433 STR(PTR)"\t2b, 11b\n\t" \ 434 STR(PTR)"\t3b, 11b\n\t" \ 435 STR(PTR)"\t4b, 11b\n\t" \ 436 ".previous" \ 437 : "=&r" (res) \ 438 : "r" (value), "r" (addr), "i" (-EFAULT) \ 439 : "memory"); \ 440 } while(0) 441 442 #define _StoreDW(addr, value, res) \ 443 do { \ 444 __asm__ __volatile__ ( \ 445 ".set\tpush\n\t" \ 446 ".set\tnoat\n\t" \ 447 "1:sb\t%1, 7(%2)\n\t" \ 448 "dsrl\t$1, %1, 0x8\n\t" \ 449 "2:sb\t$1, 6(%2)\n\t" \ 450 "dsrl\t$1, $1, 0x8\n\t" \ 451 "3:sb\t$1, 5(%2)\n\t" \ 452 "dsrl\t$1, $1, 0x8\n\t" \ 453 "4:sb\t$1, 4(%2)\n\t" \ 454 "dsrl\t$1, $1, 0x8\n\t" \ 455 "5:sb\t$1, 3(%2)\n\t" \ 456 "dsrl\t$1, $1, 0x8\n\t" \ 457 "6:sb\t$1, 2(%2)\n\t" \ 458 "dsrl\t$1, $1, 0x8\n\t" \ 459 "7:sb\t$1, 1(%2)\n\t" \ 460 "dsrl\t$1, $1, 0x8\n\t" \ 461 "8:sb\t$1, 0(%2)\n\t" \ 462 "dsrl\t$1, $1, 0x8\n\t" \ 463 ".set\tpop\n\t" \ 464 "li\t%0, 0\n" \ 465 "10:\n\t" \ 466 ".insn\n\t" \ 467 ".section\t.fixup,\"ax\"\n\t" \ 468 "11:\tli\t%0, %3\n\t" \ 469 "j\t10b\n\t" \ 470 ".previous\n\t" \ 471 ".section\t__ex_table,\"a\"\n\t" \ 472 STR(PTR)"\t1b, 11b\n\t" \ 473 STR(PTR)"\t2b, 11b\n\t" \ 474 STR(PTR)"\t3b, 11b\n\t" \ 475 STR(PTR)"\t4b, 11b\n\t" \ 476 STR(PTR)"\t5b, 11b\n\t" \ 477 STR(PTR)"\t6b, 11b\n\t" \ 478 STR(PTR)"\t7b, 11b\n\t" \ 479 STR(PTR)"\t8b, 11b\n\t" \ 480 ".previous" \ 481 : "=&r" (res) \ 482 : "r" (value), "r" (addr), "i" (-EFAULT) \ 483 : "memory"); \ 484 } while(0) 485 486 #endif /* CONFIG_CPU_MIPSR6 */ 487 488 #else /* __BIG_ENDIAN */ 489 490 #define _LoadHW(addr, value, res, type) \ 491 do { \ 492 __asm__ __volatile__ (".set\tnoat\n" \ 493 "1:\t"type##_lb("%0", "1(%2)")"\n" \ 494 "2:\t"type##_lbu("$1", "0(%2)")"\n\t"\ 495 "sll\t%0, 0x8\n\t" \ 496 "or\t%0, $1\n\t" \ 497 "li\t%1, 0\n" \ 498 "3:\t.set\tat\n\t" \ 499 ".insn\n\t" \ 500 ".section\t.fixup,\"ax\"\n\t" \ 501 "4:\tli\t%1, %3\n\t" \ 502 "j\t3b\n\t" \ 503 ".previous\n\t" \ 504 ".section\t__ex_table,\"a\"\n\t" \ 505 STR(PTR)"\t1b, 4b\n\t" \ 506 STR(PTR)"\t2b, 4b\n\t" \ 507 ".previous" \ 508 : "=&r" (value), "=r" (res) \ 509 : "r" (addr), "i" (-EFAULT)); \ 510 } while(0) 511 512 #ifndef CONFIG_CPU_MIPSR6 513 #define _LoadW(addr, value, res, type) \ 514 do { \ 515 __asm__ __volatile__ ( \ 516 "1:\t"type##_lwl("%0", "3(%2)")"\n" \ 517 "2:\t"type##_lwr("%0", "(%2)")"\n\t"\ 518 "li\t%1, 0\n" \ 519 "3:\n\t" \ 520 ".insn\n\t" \ 521 ".section\t.fixup,\"ax\"\n\t" \ 522 "4:\tli\t%1, %3\n\t" \ 523 "j\t3b\n\t" \ 524 ".previous\n\t" \ 525 ".section\t__ex_table,\"a\"\n\t" \ 526 STR(PTR)"\t1b, 4b\n\t" \ 527 STR(PTR)"\t2b, 4b\n\t" \ 528 ".previous" \ 529 : "=&r" (value), "=r" (res) \ 530 : "r" (addr), "i" (-EFAULT)); \ 531 } while(0) 532 533 #else 534 /* MIPSR6 has no lwl instruction */ 535 #define _LoadW(addr, value, res, type) \ 536 do { \ 537 __asm__ __volatile__ ( \ 538 ".set\tpush\n" \ 539 ".set\tnoat\n\t" \ 540 "1:"type##_lb("%0", "3(%2)")"\n\t" \ 541 "2:"type##_lbu("$1", "2(%2)")"\n\t" \ 542 "sll\t%0, 0x8\n\t" \ 543 "or\t%0, $1\n\t" \ 544 "3:"type##_lbu("$1", "1(%2)")"\n\t" \ 545 "sll\t%0, 0x8\n\t" \ 546 "or\t%0, $1\n\t" \ 547 "4:"type##_lbu("$1", "0(%2)")"\n\t" \ 548 "sll\t%0, 0x8\n\t" \ 549 "or\t%0, $1\n\t" \ 550 "li\t%1, 0\n" \ 551 ".set\tpop\n" \ 552 "10:\n\t" \ 553 ".insn\n\t" \ 554 ".section\t.fixup,\"ax\"\n\t" \ 555 "11:\tli\t%1, %3\n\t" \ 556 "j\t10b\n\t" \ 557 ".previous\n\t" \ 558 ".section\t__ex_table,\"a\"\n\t" \ 559 STR(PTR)"\t1b, 11b\n\t" \ 560 STR(PTR)"\t2b, 11b\n\t" \ 561 STR(PTR)"\t3b, 11b\n\t" \ 562 STR(PTR)"\t4b, 11b\n\t" \ 563 ".previous" \ 564 : "=&r" (value), "=r" (res) \ 565 : "r" (addr), "i" (-EFAULT)); \ 566 } while(0) 567 568 #endif /* CONFIG_CPU_MIPSR6 */ 569 570 571 #define _LoadHWU(addr, value, res, type) \ 572 do { \ 573 __asm__ __volatile__ ( \ 574 ".set\tnoat\n" \ 575 "1:\t"type##_lbu("%0", "1(%2)")"\n" \ 576 "2:\t"type##_lbu("$1", "0(%2)")"\n\t"\ 577 "sll\t%0, 0x8\n\t" \ 578 "or\t%0, $1\n\t" \ 579 "li\t%1, 0\n" \ 580 "3:\n\t" \ 581 ".insn\n\t" \ 582 ".set\tat\n\t" \ 583 ".section\t.fixup,\"ax\"\n\t" \ 584 "4:\tli\t%1, %3\n\t" \ 585 "j\t3b\n\t" \ 586 ".previous\n\t" \ 587 ".section\t__ex_table,\"a\"\n\t" \ 588 STR(PTR)"\t1b, 4b\n\t" \ 589 STR(PTR)"\t2b, 4b\n\t" \ 590 ".previous" \ 591 : "=&r" (value), "=r" (res) \ 592 : "r" (addr), "i" (-EFAULT)); \ 593 } while(0) 594 595 #ifndef CONFIG_CPU_MIPSR6 596 #define _LoadWU(addr, value, res, type) \ 597 do { \ 598 __asm__ __volatile__ ( \ 599 "1:\t"type##_lwl("%0", "3(%2)")"\n" \ 600 "2:\t"type##_lwr("%0", "(%2)")"\n\t"\ 601 "dsll\t%0, %0, 32\n\t" \ 602 "dsrl\t%0, %0, 32\n\t" \ 603 "li\t%1, 0\n" \ 604 "3:\n\t" \ 605 ".insn\n\t" \ 606 "\t.section\t.fixup,\"ax\"\n\t" \ 607 "4:\tli\t%1, %3\n\t" \ 608 "j\t3b\n\t" \ 609 ".previous\n\t" \ 610 ".section\t__ex_table,\"a\"\n\t" \ 611 STR(PTR)"\t1b, 4b\n\t" \ 612 STR(PTR)"\t2b, 4b\n\t" \ 613 ".previous" \ 614 : "=&r" (value), "=r" (res) \ 615 : "r" (addr), "i" (-EFAULT)); \ 616 } while(0) 617 618 #define _LoadDW(addr, value, res) \ 619 do { \ 620 __asm__ __volatile__ ( \ 621 "1:\tldl\t%0, 7(%2)\n" \ 622 "2:\tldr\t%0, (%2)\n\t" \ 623 "li\t%1, 0\n" \ 624 "3:\n\t" \ 625 ".insn\n\t" \ 626 "\t.section\t.fixup,\"ax\"\n\t" \ 627 "4:\tli\t%1, %3\n\t" \ 628 "j\t3b\n\t" \ 629 ".previous\n\t" \ 630 ".section\t__ex_table,\"a\"\n\t" \ 631 STR(PTR)"\t1b, 4b\n\t" \ 632 STR(PTR)"\t2b, 4b\n\t" \ 633 ".previous" \ 634 : "=&r" (value), "=r" (res) \ 635 : "r" (addr), "i" (-EFAULT)); \ 636 } while(0) 637 638 #else 639 /* MIPSR6 has not lwl and ldl instructions */ 640 #define _LoadWU(addr, value, res, type) \ 641 do { \ 642 __asm__ __volatile__ ( \ 643 ".set\tpush\n\t" \ 644 ".set\tnoat\n\t" \ 645 "1:"type##_lbu("%0", "3(%2)")"\n\t" \ 646 "2:"type##_lbu("$1", "2(%2)")"\n\t" \ 647 "sll\t%0, 0x8\n\t" \ 648 "or\t%0, $1\n\t" \ 649 "3:"type##_lbu("$1", "1(%2)")"\n\t" \ 650 "sll\t%0, 0x8\n\t" \ 651 "or\t%0, $1\n\t" \ 652 "4:"type##_lbu("$1", "0(%2)")"\n\t" \ 653 "sll\t%0, 0x8\n\t" \ 654 "or\t%0, $1\n\t" \ 655 "li\t%1, 0\n" \ 656 ".set\tpop\n" \ 657 "10:\n\t" \ 658 ".insn\n\t" \ 659 ".section\t.fixup,\"ax\"\n\t" \ 660 "11:\tli\t%1, %3\n\t" \ 661 "j\t10b\n\t" \ 662 ".previous\n\t" \ 663 ".section\t__ex_table,\"a\"\n\t" \ 664 STR(PTR)"\t1b, 11b\n\t" \ 665 STR(PTR)"\t2b, 11b\n\t" \ 666 STR(PTR)"\t3b, 11b\n\t" \ 667 STR(PTR)"\t4b, 11b\n\t" \ 668 ".previous" \ 669 : "=&r" (value), "=r" (res) \ 670 : "r" (addr), "i" (-EFAULT)); \ 671 } while(0) 672 673 #define _LoadDW(addr, value, res) \ 674 do { \ 675 __asm__ __volatile__ ( \ 676 ".set\tpush\n\t" \ 677 ".set\tnoat\n\t" \ 678 "1:lb\t%0, 7(%2)\n\t" \ 679 "2:lbu\t$1, 6(%2)\n\t" \ 680 "dsll\t%0, 0x8\n\t" \ 681 "or\t%0, $1\n\t" \ 682 "3:lbu\t$1, 5(%2)\n\t" \ 683 "dsll\t%0, 0x8\n\t" \ 684 "or\t%0, $1\n\t" \ 685 "4:lbu\t$1, 4(%2)\n\t" \ 686 "dsll\t%0, 0x8\n\t" \ 687 "or\t%0, $1\n\t" \ 688 "5:lbu\t$1, 3(%2)\n\t" \ 689 "dsll\t%0, 0x8\n\t" \ 690 "or\t%0, $1\n\t" \ 691 "6:lbu\t$1, 2(%2)\n\t" \ 692 "dsll\t%0, 0x8\n\t" \ 693 "or\t%0, $1\n\t" \ 694 "7:lbu\t$1, 1(%2)\n\t" \ 695 "dsll\t%0, 0x8\n\t" \ 696 "or\t%0, $1\n\t" \ 697 "8:lbu\t$1, 0(%2)\n\t" \ 698 "dsll\t%0, 0x8\n\t" \ 699 "or\t%0, $1\n\t" \ 700 "li\t%1, 0\n" \ 701 ".set\tpop\n\t" \ 702 "10:\n\t" \ 703 ".insn\n\t" \ 704 ".section\t.fixup,\"ax\"\n\t" \ 705 "11:\tli\t%1, %3\n\t" \ 706 "j\t10b\n\t" \ 707 ".previous\n\t" \ 708 ".section\t__ex_table,\"a\"\n\t" \ 709 STR(PTR)"\t1b, 11b\n\t" \ 710 STR(PTR)"\t2b, 11b\n\t" \ 711 STR(PTR)"\t3b, 11b\n\t" \ 712 STR(PTR)"\t4b, 11b\n\t" \ 713 STR(PTR)"\t5b, 11b\n\t" \ 714 STR(PTR)"\t6b, 11b\n\t" \ 715 STR(PTR)"\t7b, 11b\n\t" \ 716 STR(PTR)"\t8b, 11b\n\t" \ 717 ".previous" \ 718 : "=&r" (value), "=r" (res) \ 719 : "r" (addr), "i" (-EFAULT)); \ 720 } while(0) 721 #endif /* CONFIG_CPU_MIPSR6 */ 722 723 #define _StoreHW(addr, value, res, type) \ 724 do { \ 725 __asm__ __volatile__ ( \ 726 ".set\tnoat\n" \ 727 "1:\t"type##_sb("%1", "0(%2)")"\n" \ 728 "srl\t$1,%1, 0x8\n" \ 729 "2:\t"type##_sb("$1", "1(%2)")"\n" \ 730 ".set\tat\n\t" \ 731 "li\t%0, 0\n" \ 732 "3:\n\t" \ 733 ".insn\n\t" \ 734 ".section\t.fixup,\"ax\"\n\t" \ 735 "4:\tli\t%0, %3\n\t" \ 736 "j\t3b\n\t" \ 737 ".previous\n\t" \ 738 ".section\t__ex_table,\"a\"\n\t" \ 739 STR(PTR)"\t1b, 4b\n\t" \ 740 STR(PTR)"\t2b, 4b\n\t" \ 741 ".previous" \ 742 : "=r" (res) \ 743 : "r" (value), "r" (addr), "i" (-EFAULT));\ 744 } while(0) 745 746 #ifndef CONFIG_CPU_MIPSR6 747 #define _StoreW(addr, value, res, type) \ 748 do { \ 749 __asm__ __volatile__ ( \ 750 "1:\t"type##_swl("%1", "3(%2)")"\n" \ 751 "2:\t"type##_swr("%1", "(%2)")"\n\t"\ 752 "li\t%0, 0\n" \ 753 "3:\n\t" \ 754 ".insn\n\t" \ 755 ".section\t.fixup,\"ax\"\n\t" \ 756 "4:\tli\t%0, %3\n\t" \ 757 "j\t3b\n\t" \ 758 ".previous\n\t" \ 759 ".section\t__ex_table,\"a\"\n\t" \ 760 STR(PTR)"\t1b, 4b\n\t" \ 761 STR(PTR)"\t2b, 4b\n\t" \ 762 ".previous" \ 763 : "=r" (res) \ 764 : "r" (value), "r" (addr), "i" (-EFAULT)); \ 765 } while(0) 766 767 #define _StoreDW(addr, value, res) \ 768 do { \ 769 __asm__ __volatile__ ( \ 770 "1:\tsdl\t%1, 7(%2)\n" \ 771 "2:\tsdr\t%1, (%2)\n\t" \ 772 "li\t%0, 0\n" \ 773 "3:\n\t" \ 774 ".insn\n\t" \ 775 ".section\t.fixup,\"ax\"\n\t" \ 776 "4:\tli\t%0, %3\n\t" \ 777 "j\t3b\n\t" \ 778 ".previous\n\t" \ 779 ".section\t__ex_table,\"a\"\n\t" \ 780 STR(PTR)"\t1b, 4b\n\t" \ 781 STR(PTR)"\t2b, 4b\n\t" \ 782 ".previous" \ 783 : "=r" (res) \ 784 : "r" (value), "r" (addr), "i" (-EFAULT)); \ 785 } while(0) 786 787 #else 788 /* MIPSR6 has no swl and sdl instructions */ 789 #define _StoreW(addr, value, res, type) \ 790 do { \ 791 __asm__ __volatile__ ( \ 792 ".set\tpush\n\t" \ 793 ".set\tnoat\n\t" \ 794 "1:"type##_sb("%1", "0(%2)")"\n\t" \ 795 "srl\t$1, %1, 0x8\n\t" \ 796 "2:"type##_sb("$1", "1(%2)")"\n\t" \ 797 "srl\t$1, $1, 0x8\n\t" \ 798 "3:"type##_sb("$1", "2(%2)")"\n\t" \ 799 "srl\t$1, $1, 0x8\n\t" \ 800 "4:"type##_sb("$1", "3(%2)")"\n\t" \ 801 ".set\tpop\n\t" \ 802 "li\t%0, 0\n" \ 803 "10:\n\t" \ 804 ".insn\n\t" \ 805 ".section\t.fixup,\"ax\"\n\t" \ 806 "11:\tli\t%0, %3\n\t" \ 807 "j\t10b\n\t" \ 808 ".previous\n\t" \ 809 ".section\t__ex_table,\"a\"\n\t" \ 810 STR(PTR)"\t1b, 11b\n\t" \ 811 STR(PTR)"\t2b, 11b\n\t" \ 812 STR(PTR)"\t3b, 11b\n\t" \ 813 STR(PTR)"\t4b, 11b\n\t" \ 814 ".previous" \ 815 : "=&r" (res) \ 816 : "r" (value), "r" (addr), "i" (-EFAULT) \ 817 : "memory"); \ 818 } while(0) 819 820 #define _StoreDW(addr, value, res) \ 821 do { \ 822 __asm__ __volatile__ ( \ 823 ".set\tpush\n\t" \ 824 ".set\tnoat\n\t" \ 825 "1:sb\t%1, 0(%2)\n\t" \ 826 "dsrl\t$1, %1, 0x8\n\t" \ 827 "2:sb\t$1, 1(%2)\n\t" \ 828 "dsrl\t$1, $1, 0x8\n\t" \ 829 "3:sb\t$1, 2(%2)\n\t" \ 830 "dsrl\t$1, $1, 0x8\n\t" \ 831 "4:sb\t$1, 3(%2)\n\t" \ 832 "dsrl\t$1, $1, 0x8\n\t" \ 833 "5:sb\t$1, 4(%2)\n\t" \ 834 "dsrl\t$1, $1, 0x8\n\t" \ 835 "6:sb\t$1, 5(%2)\n\t" \ 836 "dsrl\t$1, $1, 0x8\n\t" \ 837 "7:sb\t$1, 6(%2)\n\t" \ 838 "dsrl\t$1, $1, 0x8\n\t" \ 839 "8:sb\t$1, 7(%2)\n\t" \ 840 "dsrl\t$1, $1, 0x8\n\t" \ 841 ".set\tpop\n\t" \ 842 "li\t%0, 0\n" \ 843 "10:\n\t" \ 844 ".insn\n\t" \ 845 ".section\t.fixup,\"ax\"\n\t" \ 846 "11:\tli\t%0, %3\n\t" \ 847 "j\t10b\n\t" \ 848 ".previous\n\t" \ 849 ".section\t__ex_table,\"a\"\n\t" \ 850 STR(PTR)"\t1b, 11b\n\t" \ 851 STR(PTR)"\t2b, 11b\n\t" \ 852 STR(PTR)"\t3b, 11b\n\t" \ 853 STR(PTR)"\t4b, 11b\n\t" \ 854 STR(PTR)"\t5b, 11b\n\t" \ 855 STR(PTR)"\t6b, 11b\n\t" \ 856 STR(PTR)"\t7b, 11b\n\t" \ 857 STR(PTR)"\t8b, 11b\n\t" \ 858 ".previous" \ 859 : "=&r" (res) \ 860 : "r" (value), "r" (addr), "i" (-EFAULT) \ 861 : "memory"); \ 862 } while(0) 863 864 #endif /* CONFIG_CPU_MIPSR6 */ 865 #endif 866 867 #define LoadHWU(addr, value, res) _LoadHWU(addr, value, res, kernel) 868 #define LoadHWUE(addr, value, res) _LoadHWU(addr, value, res, user) 869 #define LoadWU(addr, value, res) _LoadWU(addr, value, res, kernel) 870 #define LoadWUE(addr, value, res) _LoadWU(addr, value, res, user) 871 #define LoadHW(addr, value, res) _LoadHW(addr, value, res, kernel) 872 #define LoadHWE(addr, value, res) _LoadHW(addr, value, res, user) 873 #define LoadW(addr, value, res) _LoadW(addr, value, res, kernel) 874 #define LoadWE(addr, value, res) _LoadW(addr, value, res, user) 875 #define LoadDW(addr, value, res) _LoadDW(addr, value, res) 876 877 #define StoreHW(addr, value, res) _StoreHW(addr, value, res, kernel) 878 #define StoreHWE(addr, value, res) _StoreHW(addr, value, res, user) 879 #define StoreW(addr, value, res) _StoreW(addr, value, res, kernel) 880 #define StoreWE(addr, value, res) _StoreW(addr, value, res, user) 881 #define StoreDW(addr, value, res) _StoreDW(addr, value, res) 882 883 static void emulate_load_store_insn(struct pt_regs *regs, 884 void __user *addr, unsigned int __user *pc) 885 { 886 union mips_instruction insn; 887 unsigned long value; 888 unsigned int res, preempted; 889 unsigned long origpc; 890 unsigned long orig31; 891 void __user *fault_addr = NULL; 892 #ifdef CONFIG_EVA 893 mm_segment_t seg; 894 #endif 895 union fpureg *fpr; 896 enum msa_2b_fmt df; 897 unsigned int wd; 898 origpc = (unsigned long)pc; 899 orig31 = regs->regs[31]; 900 901 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0); 902 903 /* 904 * This load never faults. 905 */ 906 __get_user(insn.word, pc); 907 908 switch (insn.i_format.opcode) { 909 /* 910 * These are instructions that a compiler doesn't generate. We 911 * can assume therefore that the code is MIPS-aware and 912 * really buggy. Emulating these instructions would break the 913 * semantics anyway. 914 */ 915 case ll_op: 916 case lld_op: 917 case sc_op: 918 case scd_op: 919 920 /* 921 * For these instructions the only way to create an address 922 * error is an attempted access to kernel/supervisor address 923 * space. 924 */ 925 case ldl_op: 926 case ldr_op: 927 case lwl_op: 928 case lwr_op: 929 case sdl_op: 930 case sdr_op: 931 case swl_op: 932 case swr_op: 933 case lb_op: 934 case lbu_op: 935 case sb_op: 936 goto sigbus; 937 938 /* 939 * The remaining opcodes are the ones that are really of 940 * interest. 941 */ 942 #ifdef CONFIG_EVA 943 case spec3_op: 944 /* 945 * we can land here only from kernel accessing user memory, 946 * so we need to "switch" the address limit to user space, so 947 * address check can work properly. 948 */ 949 seg = get_fs(); 950 set_fs(USER_DS); 951 switch (insn.spec3_format.func) { 952 case lhe_op: 953 if (!access_ok(VERIFY_READ, addr, 2)) { 954 set_fs(seg); 955 goto sigbus; 956 } 957 LoadHWE(addr, value, res); 958 if (res) { 959 set_fs(seg); 960 goto fault; 961 } 962 compute_return_epc(regs); 963 regs->regs[insn.spec3_format.rt] = value; 964 break; 965 case lwe_op: 966 if (!access_ok(VERIFY_READ, addr, 4)) { 967 set_fs(seg); 968 goto sigbus; 969 } 970 LoadWE(addr, value, res); 971 if (res) { 972 set_fs(seg); 973 goto fault; 974 } 975 compute_return_epc(regs); 976 regs->regs[insn.spec3_format.rt] = value; 977 break; 978 case lhue_op: 979 if (!access_ok(VERIFY_READ, addr, 2)) { 980 set_fs(seg); 981 goto sigbus; 982 } 983 LoadHWUE(addr, value, res); 984 if (res) { 985 set_fs(seg); 986 goto fault; 987 } 988 compute_return_epc(regs); 989 regs->regs[insn.spec3_format.rt] = value; 990 break; 991 case she_op: 992 if (!access_ok(VERIFY_WRITE, addr, 2)) { 993 set_fs(seg); 994 goto sigbus; 995 } 996 compute_return_epc(regs); 997 value = regs->regs[insn.spec3_format.rt]; 998 StoreHWE(addr, value, res); 999 if (res) { 1000 set_fs(seg); 1001 goto fault; 1002 } 1003 break; 1004 case swe_op: 1005 if (!access_ok(VERIFY_WRITE, addr, 4)) { 1006 set_fs(seg); 1007 goto sigbus; 1008 } 1009 compute_return_epc(regs); 1010 value = regs->regs[insn.spec3_format.rt]; 1011 StoreWE(addr, value, res); 1012 if (res) { 1013 set_fs(seg); 1014 goto fault; 1015 } 1016 break; 1017 default: 1018 set_fs(seg); 1019 goto sigill; 1020 } 1021 set_fs(seg); 1022 break; 1023 #endif 1024 case lh_op: 1025 if (!access_ok(VERIFY_READ, addr, 2)) 1026 goto sigbus; 1027 1028 if (config_enabled(CONFIG_EVA)) { 1029 if (segment_eq(get_fs(), get_ds())) 1030 LoadHW(addr, value, res); 1031 else 1032 LoadHWE(addr, value, res); 1033 } else { 1034 LoadHW(addr, value, res); 1035 } 1036 1037 if (res) 1038 goto fault; 1039 compute_return_epc(regs); 1040 regs->regs[insn.i_format.rt] = value; 1041 break; 1042 1043 case lw_op: 1044 if (!access_ok(VERIFY_READ, addr, 4)) 1045 goto sigbus; 1046 1047 if (config_enabled(CONFIG_EVA)) { 1048 if (segment_eq(get_fs(), get_ds())) 1049 LoadW(addr, value, res); 1050 else 1051 LoadWE(addr, value, res); 1052 } else { 1053 LoadW(addr, value, res); 1054 } 1055 1056 if (res) 1057 goto fault; 1058 compute_return_epc(regs); 1059 regs->regs[insn.i_format.rt] = value; 1060 break; 1061 1062 case lhu_op: 1063 if (!access_ok(VERIFY_READ, addr, 2)) 1064 goto sigbus; 1065 1066 if (config_enabled(CONFIG_EVA)) { 1067 if (segment_eq(get_fs(), get_ds())) 1068 LoadHWU(addr, value, res); 1069 else 1070 LoadHWUE(addr, value, res); 1071 } else { 1072 LoadHWU(addr, value, res); 1073 } 1074 1075 if (res) 1076 goto fault; 1077 compute_return_epc(regs); 1078 regs->regs[insn.i_format.rt] = value; 1079 break; 1080 1081 case lwu_op: 1082 #ifdef CONFIG_64BIT 1083 /* 1084 * A 32-bit kernel might be running on a 64-bit processor. But 1085 * if we're on a 32-bit processor and an i-cache incoherency 1086 * or race makes us see a 64-bit instruction here the sdl/sdr 1087 * would blow up, so for now we don't handle unaligned 64-bit 1088 * instructions on 32-bit kernels. 1089 */ 1090 if (!access_ok(VERIFY_READ, addr, 4)) 1091 goto sigbus; 1092 1093 LoadWU(addr, value, res); 1094 if (res) 1095 goto fault; 1096 compute_return_epc(regs); 1097 regs->regs[insn.i_format.rt] = value; 1098 break; 1099 #endif /* CONFIG_64BIT */ 1100 1101 /* Cannot handle 64-bit instructions in 32-bit kernel */ 1102 goto sigill; 1103 1104 case ld_op: 1105 #ifdef CONFIG_64BIT 1106 /* 1107 * A 32-bit kernel might be running on a 64-bit processor. But 1108 * if we're on a 32-bit processor and an i-cache incoherency 1109 * or race makes us see a 64-bit instruction here the sdl/sdr 1110 * would blow up, so for now we don't handle unaligned 64-bit 1111 * instructions on 32-bit kernels. 1112 */ 1113 if (!access_ok(VERIFY_READ, addr, 8)) 1114 goto sigbus; 1115 1116 LoadDW(addr, value, res); 1117 if (res) 1118 goto fault; 1119 compute_return_epc(regs); 1120 regs->regs[insn.i_format.rt] = value; 1121 break; 1122 #endif /* CONFIG_64BIT */ 1123 1124 /* Cannot handle 64-bit instructions in 32-bit kernel */ 1125 goto sigill; 1126 1127 case sh_op: 1128 if (!access_ok(VERIFY_WRITE, addr, 2)) 1129 goto sigbus; 1130 1131 compute_return_epc(regs); 1132 value = regs->regs[insn.i_format.rt]; 1133 1134 if (config_enabled(CONFIG_EVA)) { 1135 if (segment_eq(get_fs(), get_ds())) 1136 StoreHW(addr, value, res); 1137 else 1138 StoreHWE(addr, value, res); 1139 } else { 1140 StoreHW(addr, value, res); 1141 } 1142 1143 if (res) 1144 goto fault; 1145 break; 1146 1147 case sw_op: 1148 if (!access_ok(VERIFY_WRITE, addr, 4)) 1149 goto sigbus; 1150 1151 compute_return_epc(regs); 1152 value = regs->regs[insn.i_format.rt]; 1153 1154 if (config_enabled(CONFIG_EVA)) { 1155 if (segment_eq(get_fs(), get_ds())) 1156 StoreW(addr, value, res); 1157 else 1158 StoreWE(addr, value, res); 1159 } else { 1160 StoreW(addr, value, res); 1161 } 1162 1163 if (res) 1164 goto fault; 1165 break; 1166 1167 case sd_op: 1168 #ifdef CONFIG_64BIT 1169 /* 1170 * A 32-bit kernel might be running on a 64-bit processor. But 1171 * if we're on a 32-bit processor and an i-cache incoherency 1172 * or race makes us see a 64-bit instruction here the sdl/sdr 1173 * would blow up, so for now we don't handle unaligned 64-bit 1174 * instructions on 32-bit kernels. 1175 */ 1176 if (!access_ok(VERIFY_WRITE, addr, 8)) 1177 goto sigbus; 1178 1179 compute_return_epc(regs); 1180 value = regs->regs[insn.i_format.rt]; 1181 StoreDW(addr, value, res); 1182 if (res) 1183 goto fault; 1184 break; 1185 #endif /* CONFIG_64BIT */ 1186 1187 /* Cannot handle 64-bit instructions in 32-bit kernel */ 1188 goto sigill; 1189 1190 case lwc1_op: 1191 case ldc1_op: 1192 case swc1_op: 1193 case sdc1_op: 1194 case cop1x_op: 1195 die_if_kernel("Unaligned FP access in kernel code", regs); 1196 BUG_ON(!used_math()); 1197 1198 lose_fpu(1); /* Save FPU state for the emulator. */ 1199 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, 1200 &fault_addr); 1201 own_fpu(1); /* Restore FPU state. */ 1202 1203 /* Signal if something went wrong. */ 1204 process_fpemu_return(res, fault_addr, 0); 1205 1206 if (res == 0) 1207 break; 1208 return; 1209 1210 case msa_op: 1211 if (!cpu_has_msa) 1212 goto sigill; 1213 1214 /* 1215 * If we've reached this point then userland should have taken 1216 * the MSA disabled exception & initialised vector context at 1217 * some point in the past. 1218 */ 1219 BUG_ON(!thread_msa_context_live()); 1220 1221 df = insn.msa_mi10_format.df; 1222 wd = insn.msa_mi10_format.wd; 1223 fpr = ¤t->thread.fpu.fpr[wd]; 1224 1225 switch (insn.msa_mi10_format.func) { 1226 case msa_ld_op: 1227 if (!access_ok(VERIFY_READ, addr, sizeof(*fpr))) 1228 goto sigbus; 1229 1230 do { 1231 /* 1232 * If we have live MSA context keep track of 1233 * whether we get preempted in order to avoid 1234 * the register context we load being clobbered 1235 * by the live context as it's saved during 1236 * preemption. If we don't have live context 1237 * then it can't be saved to clobber the value 1238 * we load. 1239 */ 1240 preempted = test_thread_flag(TIF_USEDMSA); 1241 1242 res = __copy_from_user_inatomic(fpr, addr, 1243 sizeof(*fpr)); 1244 if (res) 1245 goto fault; 1246 1247 /* 1248 * Update the hardware register if it is in use 1249 * by the task in this quantum, in order to 1250 * avoid having to save & restore the whole 1251 * vector context. 1252 */ 1253 preempt_disable(); 1254 if (test_thread_flag(TIF_USEDMSA)) { 1255 write_msa_wr(wd, fpr, df); 1256 preempted = 0; 1257 } 1258 preempt_enable(); 1259 } while (preempted); 1260 break; 1261 1262 case msa_st_op: 1263 if (!access_ok(VERIFY_WRITE, addr, sizeof(*fpr))) 1264 goto sigbus; 1265 1266 /* 1267 * Update from the hardware register if it is in use by 1268 * the task in this quantum, in order to avoid having to 1269 * save & restore the whole vector context. 1270 */ 1271 preempt_disable(); 1272 if (test_thread_flag(TIF_USEDMSA)) 1273 read_msa_wr(wd, fpr, df); 1274 preempt_enable(); 1275 1276 res = __copy_to_user_inatomic(addr, fpr, sizeof(*fpr)); 1277 if (res) 1278 goto fault; 1279 break; 1280 1281 default: 1282 goto sigbus; 1283 } 1284 1285 compute_return_epc(regs); 1286 break; 1287 1288 #ifndef CONFIG_CPU_MIPSR6 1289 /* 1290 * COP2 is available to implementor for application specific use. 1291 * It's up to applications to register a notifier chain and do 1292 * whatever they have to do, including possible sending of signals. 1293 * 1294 * This instruction has been reallocated in Release 6 1295 */ 1296 case lwc2_op: 1297 cu2_notifier_call_chain(CU2_LWC2_OP, regs); 1298 break; 1299 1300 case ldc2_op: 1301 cu2_notifier_call_chain(CU2_LDC2_OP, regs); 1302 break; 1303 1304 case swc2_op: 1305 cu2_notifier_call_chain(CU2_SWC2_OP, regs); 1306 break; 1307 1308 case sdc2_op: 1309 cu2_notifier_call_chain(CU2_SDC2_OP, regs); 1310 break; 1311 #endif 1312 default: 1313 /* 1314 * Pheeee... We encountered an yet unknown instruction or 1315 * cache coherence problem. Die sucker, die ... 1316 */ 1317 goto sigill; 1318 } 1319 1320 #ifdef CONFIG_DEBUG_FS 1321 unaligned_instructions++; 1322 #endif 1323 1324 return; 1325 1326 fault: 1327 /* roll back jump/branch */ 1328 regs->cp0_epc = origpc; 1329 regs->regs[31] = orig31; 1330 /* Did we have an exception handler installed? */ 1331 if (fixup_exception(regs)) 1332 return; 1333 1334 die_if_kernel("Unhandled kernel unaligned access", regs); 1335 force_sig(SIGSEGV, current); 1336 1337 return; 1338 1339 sigbus: 1340 die_if_kernel("Unhandled kernel unaligned access", regs); 1341 force_sig(SIGBUS, current); 1342 1343 return; 1344 1345 sigill: 1346 die_if_kernel 1347 ("Unhandled kernel unaligned access or invalid instruction", regs); 1348 force_sig(SIGILL, current); 1349 } 1350 1351 /* Recode table from 16-bit register notation to 32-bit GPR. */ 1352 const int reg16to32[] = { 16, 17, 2, 3, 4, 5, 6, 7 }; 1353 1354 /* Recode table from 16-bit STORE register notation to 32-bit GPR. */ 1355 const int reg16to32st[] = { 0, 17, 2, 3, 4, 5, 6, 7 }; 1356 1357 static void emulate_load_store_microMIPS(struct pt_regs *regs, 1358 void __user *addr) 1359 { 1360 unsigned long value; 1361 unsigned int res; 1362 int i; 1363 unsigned int reg = 0, rvar; 1364 unsigned long orig31; 1365 u16 __user *pc16; 1366 u16 halfword; 1367 unsigned int word; 1368 unsigned long origpc, contpc; 1369 union mips_instruction insn; 1370 struct mm_decoded_insn mminsn; 1371 void __user *fault_addr = NULL; 1372 1373 origpc = regs->cp0_epc; 1374 orig31 = regs->regs[31]; 1375 1376 mminsn.micro_mips_mode = 1; 1377 1378 /* 1379 * This load never faults. 1380 */ 1381 pc16 = (unsigned short __user *)msk_isa16_mode(regs->cp0_epc); 1382 __get_user(halfword, pc16); 1383 pc16++; 1384 contpc = regs->cp0_epc + 2; 1385 word = ((unsigned int)halfword << 16); 1386 mminsn.pc_inc = 2; 1387 1388 if (!mm_insn_16bit(halfword)) { 1389 __get_user(halfword, pc16); 1390 pc16++; 1391 contpc = regs->cp0_epc + 4; 1392 mminsn.pc_inc = 4; 1393 word |= halfword; 1394 } 1395 mminsn.insn = word; 1396 1397 if (get_user(halfword, pc16)) 1398 goto fault; 1399 mminsn.next_pc_inc = 2; 1400 word = ((unsigned int)halfword << 16); 1401 1402 if (!mm_insn_16bit(halfword)) { 1403 pc16++; 1404 if (get_user(halfword, pc16)) 1405 goto fault; 1406 mminsn.next_pc_inc = 4; 1407 word |= halfword; 1408 } 1409 mminsn.next_insn = word; 1410 1411 insn = (union mips_instruction)(mminsn.insn); 1412 if (mm_isBranchInstr(regs, mminsn, &contpc)) 1413 insn = (union mips_instruction)(mminsn.next_insn); 1414 1415 /* Parse instruction to find what to do */ 1416 1417 switch (insn.mm_i_format.opcode) { 1418 1419 case mm_pool32a_op: 1420 switch (insn.mm_x_format.func) { 1421 case mm_lwxs_op: 1422 reg = insn.mm_x_format.rd; 1423 goto loadW; 1424 } 1425 1426 goto sigbus; 1427 1428 case mm_pool32b_op: 1429 switch (insn.mm_m_format.func) { 1430 case mm_lwp_func: 1431 reg = insn.mm_m_format.rd; 1432 if (reg == 31) 1433 goto sigbus; 1434 1435 if (!access_ok(VERIFY_READ, addr, 8)) 1436 goto sigbus; 1437 1438 LoadW(addr, value, res); 1439 if (res) 1440 goto fault; 1441 regs->regs[reg] = value; 1442 addr += 4; 1443 LoadW(addr, value, res); 1444 if (res) 1445 goto fault; 1446 regs->regs[reg + 1] = value; 1447 goto success; 1448 1449 case mm_swp_func: 1450 reg = insn.mm_m_format.rd; 1451 if (reg == 31) 1452 goto sigbus; 1453 1454 if (!access_ok(VERIFY_WRITE, addr, 8)) 1455 goto sigbus; 1456 1457 value = regs->regs[reg]; 1458 StoreW(addr, value, res); 1459 if (res) 1460 goto fault; 1461 addr += 4; 1462 value = regs->regs[reg + 1]; 1463 StoreW(addr, value, res); 1464 if (res) 1465 goto fault; 1466 goto success; 1467 1468 case mm_ldp_func: 1469 #ifdef CONFIG_64BIT 1470 reg = insn.mm_m_format.rd; 1471 if (reg == 31) 1472 goto sigbus; 1473 1474 if (!access_ok(VERIFY_READ, addr, 16)) 1475 goto sigbus; 1476 1477 LoadDW(addr, value, res); 1478 if (res) 1479 goto fault; 1480 regs->regs[reg] = value; 1481 addr += 8; 1482 LoadDW(addr, value, res); 1483 if (res) 1484 goto fault; 1485 regs->regs[reg + 1] = value; 1486 goto success; 1487 #endif /* CONFIG_64BIT */ 1488 1489 goto sigill; 1490 1491 case mm_sdp_func: 1492 #ifdef CONFIG_64BIT 1493 reg = insn.mm_m_format.rd; 1494 if (reg == 31) 1495 goto sigbus; 1496 1497 if (!access_ok(VERIFY_WRITE, addr, 16)) 1498 goto sigbus; 1499 1500 value = regs->regs[reg]; 1501 StoreDW(addr, value, res); 1502 if (res) 1503 goto fault; 1504 addr += 8; 1505 value = regs->regs[reg + 1]; 1506 StoreDW(addr, value, res); 1507 if (res) 1508 goto fault; 1509 goto success; 1510 #endif /* CONFIG_64BIT */ 1511 1512 goto sigill; 1513 1514 case mm_lwm32_func: 1515 reg = insn.mm_m_format.rd; 1516 rvar = reg & 0xf; 1517 if ((rvar > 9) || !reg) 1518 goto sigill; 1519 if (reg & 0x10) { 1520 if (!access_ok 1521 (VERIFY_READ, addr, 4 * (rvar + 1))) 1522 goto sigbus; 1523 } else { 1524 if (!access_ok(VERIFY_READ, addr, 4 * rvar)) 1525 goto sigbus; 1526 } 1527 if (rvar == 9) 1528 rvar = 8; 1529 for (i = 16; rvar; rvar--, i++) { 1530 LoadW(addr, value, res); 1531 if (res) 1532 goto fault; 1533 addr += 4; 1534 regs->regs[i] = value; 1535 } 1536 if ((reg & 0xf) == 9) { 1537 LoadW(addr, value, res); 1538 if (res) 1539 goto fault; 1540 addr += 4; 1541 regs->regs[30] = value; 1542 } 1543 if (reg & 0x10) { 1544 LoadW(addr, value, res); 1545 if (res) 1546 goto fault; 1547 regs->regs[31] = value; 1548 } 1549 goto success; 1550 1551 case mm_swm32_func: 1552 reg = insn.mm_m_format.rd; 1553 rvar = reg & 0xf; 1554 if ((rvar > 9) || !reg) 1555 goto sigill; 1556 if (reg & 0x10) { 1557 if (!access_ok 1558 (VERIFY_WRITE, addr, 4 * (rvar + 1))) 1559 goto sigbus; 1560 } else { 1561 if (!access_ok(VERIFY_WRITE, addr, 4 * rvar)) 1562 goto sigbus; 1563 } 1564 if (rvar == 9) 1565 rvar = 8; 1566 for (i = 16; rvar; rvar--, i++) { 1567 value = regs->regs[i]; 1568 StoreW(addr, value, res); 1569 if (res) 1570 goto fault; 1571 addr += 4; 1572 } 1573 if ((reg & 0xf) == 9) { 1574 value = regs->regs[30]; 1575 StoreW(addr, value, res); 1576 if (res) 1577 goto fault; 1578 addr += 4; 1579 } 1580 if (reg & 0x10) { 1581 value = regs->regs[31]; 1582 StoreW(addr, value, res); 1583 if (res) 1584 goto fault; 1585 } 1586 goto success; 1587 1588 case mm_ldm_func: 1589 #ifdef CONFIG_64BIT 1590 reg = insn.mm_m_format.rd; 1591 rvar = reg & 0xf; 1592 if ((rvar > 9) || !reg) 1593 goto sigill; 1594 if (reg & 0x10) { 1595 if (!access_ok 1596 (VERIFY_READ, addr, 8 * (rvar + 1))) 1597 goto sigbus; 1598 } else { 1599 if (!access_ok(VERIFY_READ, addr, 8 * rvar)) 1600 goto sigbus; 1601 } 1602 if (rvar == 9) 1603 rvar = 8; 1604 1605 for (i = 16; rvar; rvar--, i++) { 1606 LoadDW(addr, value, res); 1607 if (res) 1608 goto fault; 1609 addr += 4; 1610 regs->regs[i] = value; 1611 } 1612 if ((reg & 0xf) == 9) { 1613 LoadDW(addr, value, res); 1614 if (res) 1615 goto fault; 1616 addr += 8; 1617 regs->regs[30] = value; 1618 } 1619 if (reg & 0x10) { 1620 LoadDW(addr, value, res); 1621 if (res) 1622 goto fault; 1623 regs->regs[31] = value; 1624 } 1625 goto success; 1626 #endif /* CONFIG_64BIT */ 1627 1628 goto sigill; 1629 1630 case mm_sdm_func: 1631 #ifdef CONFIG_64BIT 1632 reg = insn.mm_m_format.rd; 1633 rvar = reg & 0xf; 1634 if ((rvar > 9) || !reg) 1635 goto sigill; 1636 if (reg & 0x10) { 1637 if (!access_ok 1638 (VERIFY_WRITE, addr, 8 * (rvar + 1))) 1639 goto sigbus; 1640 } else { 1641 if (!access_ok(VERIFY_WRITE, addr, 8 * rvar)) 1642 goto sigbus; 1643 } 1644 if (rvar == 9) 1645 rvar = 8; 1646 1647 for (i = 16; rvar; rvar--, i++) { 1648 value = regs->regs[i]; 1649 StoreDW(addr, value, res); 1650 if (res) 1651 goto fault; 1652 addr += 8; 1653 } 1654 if ((reg & 0xf) == 9) { 1655 value = regs->regs[30]; 1656 StoreDW(addr, value, res); 1657 if (res) 1658 goto fault; 1659 addr += 8; 1660 } 1661 if (reg & 0x10) { 1662 value = regs->regs[31]; 1663 StoreDW(addr, value, res); 1664 if (res) 1665 goto fault; 1666 } 1667 goto success; 1668 #endif /* CONFIG_64BIT */ 1669 1670 goto sigill; 1671 1672 /* LWC2, SWC2, LDC2, SDC2 are not serviced */ 1673 } 1674 1675 goto sigbus; 1676 1677 case mm_pool32c_op: 1678 switch (insn.mm_m_format.func) { 1679 case mm_lwu_func: 1680 reg = insn.mm_m_format.rd; 1681 goto loadWU; 1682 } 1683 1684 /* LL,SC,LLD,SCD are not serviced */ 1685 goto sigbus; 1686 1687 case mm_pool32f_op: 1688 switch (insn.mm_x_format.func) { 1689 case mm_lwxc1_func: 1690 case mm_swxc1_func: 1691 case mm_ldxc1_func: 1692 case mm_sdxc1_func: 1693 goto fpu_emul; 1694 } 1695 1696 goto sigbus; 1697 1698 case mm_ldc132_op: 1699 case mm_sdc132_op: 1700 case mm_lwc132_op: 1701 case mm_swc132_op: 1702 fpu_emul: 1703 /* roll back jump/branch */ 1704 regs->cp0_epc = origpc; 1705 regs->regs[31] = orig31; 1706 1707 die_if_kernel("Unaligned FP access in kernel code", regs); 1708 BUG_ON(!used_math()); 1709 BUG_ON(!is_fpu_owner()); 1710 1711 lose_fpu(1); /* save the FPU state for the emulator */ 1712 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, 1713 &fault_addr); 1714 own_fpu(1); /* restore FPU state */ 1715 1716 /* If something went wrong, signal */ 1717 process_fpemu_return(res, fault_addr, 0); 1718 1719 if (res == 0) 1720 goto success; 1721 return; 1722 1723 case mm_lh32_op: 1724 reg = insn.mm_i_format.rt; 1725 goto loadHW; 1726 1727 case mm_lhu32_op: 1728 reg = insn.mm_i_format.rt; 1729 goto loadHWU; 1730 1731 case mm_lw32_op: 1732 reg = insn.mm_i_format.rt; 1733 goto loadW; 1734 1735 case mm_sh32_op: 1736 reg = insn.mm_i_format.rt; 1737 goto storeHW; 1738 1739 case mm_sw32_op: 1740 reg = insn.mm_i_format.rt; 1741 goto storeW; 1742 1743 case mm_ld32_op: 1744 reg = insn.mm_i_format.rt; 1745 goto loadDW; 1746 1747 case mm_sd32_op: 1748 reg = insn.mm_i_format.rt; 1749 goto storeDW; 1750 1751 case mm_pool16c_op: 1752 switch (insn.mm16_m_format.func) { 1753 case mm_lwm16_op: 1754 reg = insn.mm16_m_format.rlist; 1755 rvar = reg + 1; 1756 if (!access_ok(VERIFY_READ, addr, 4 * rvar)) 1757 goto sigbus; 1758 1759 for (i = 16; rvar; rvar--, i++) { 1760 LoadW(addr, value, res); 1761 if (res) 1762 goto fault; 1763 addr += 4; 1764 regs->regs[i] = value; 1765 } 1766 LoadW(addr, value, res); 1767 if (res) 1768 goto fault; 1769 regs->regs[31] = value; 1770 1771 goto success; 1772 1773 case mm_swm16_op: 1774 reg = insn.mm16_m_format.rlist; 1775 rvar = reg + 1; 1776 if (!access_ok(VERIFY_WRITE, addr, 4 * rvar)) 1777 goto sigbus; 1778 1779 for (i = 16; rvar; rvar--, i++) { 1780 value = regs->regs[i]; 1781 StoreW(addr, value, res); 1782 if (res) 1783 goto fault; 1784 addr += 4; 1785 } 1786 value = regs->regs[31]; 1787 StoreW(addr, value, res); 1788 if (res) 1789 goto fault; 1790 1791 goto success; 1792 1793 } 1794 1795 goto sigbus; 1796 1797 case mm_lhu16_op: 1798 reg = reg16to32[insn.mm16_rb_format.rt]; 1799 goto loadHWU; 1800 1801 case mm_lw16_op: 1802 reg = reg16to32[insn.mm16_rb_format.rt]; 1803 goto loadW; 1804 1805 case mm_sh16_op: 1806 reg = reg16to32st[insn.mm16_rb_format.rt]; 1807 goto storeHW; 1808 1809 case mm_sw16_op: 1810 reg = reg16to32st[insn.mm16_rb_format.rt]; 1811 goto storeW; 1812 1813 case mm_lwsp16_op: 1814 reg = insn.mm16_r5_format.rt; 1815 goto loadW; 1816 1817 case mm_swsp16_op: 1818 reg = insn.mm16_r5_format.rt; 1819 goto storeW; 1820 1821 case mm_lwgp16_op: 1822 reg = reg16to32[insn.mm16_r3_format.rt]; 1823 goto loadW; 1824 1825 default: 1826 goto sigill; 1827 } 1828 1829 loadHW: 1830 if (!access_ok(VERIFY_READ, addr, 2)) 1831 goto sigbus; 1832 1833 LoadHW(addr, value, res); 1834 if (res) 1835 goto fault; 1836 regs->regs[reg] = value; 1837 goto success; 1838 1839 loadHWU: 1840 if (!access_ok(VERIFY_READ, addr, 2)) 1841 goto sigbus; 1842 1843 LoadHWU(addr, value, res); 1844 if (res) 1845 goto fault; 1846 regs->regs[reg] = value; 1847 goto success; 1848 1849 loadW: 1850 if (!access_ok(VERIFY_READ, addr, 4)) 1851 goto sigbus; 1852 1853 LoadW(addr, value, res); 1854 if (res) 1855 goto fault; 1856 regs->regs[reg] = value; 1857 goto success; 1858 1859 loadWU: 1860 #ifdef CONFIG_64BIT 1861 /* 1862 * A 32-bit kernel might be running on a 64-bit processor. But 1863 * if we're on a 32-bit processor and an i-cache incoherency 1864 * or race makes us see a 64-bit instruction here the sdl/sdr 1865 * would blow up, so for now we don't handle unaligned 64-bit 1866 * instructions on 32-bit kernels. 1867 */ 1868 if (!access_ok(VERIFY_READ, addr, 4)) 1869 goto sigbus; 1870 1871 LoadWU(addr, value, res); 1872 if (res) 1873 goto fault; 1874 regs->regs[reg] = value; 1875 goto success; 1876 #endif /* CONFIG_64BIT */ 1877 1878 /* Cannot handle 64-bit instructions in 32-bit kernel */ 1879 goto sigill; 1880 1881 loadDW: 1882 #ifdef CONFIG_64BIT 1883 /* 1884 * A 32-bit kernel might be running on a 64-bit processor. But 1885 * if we're on a 32-bit processor and an i-cache incoherency 1886 * or race makes us see a 64-bit instruction here the sdl/sdr 1887 * would blow up, so for now we don't handle unaligned 64-bit 1888 * instructions on 32-bit kernels. 1889 */ 1890 if (!access_ok(VERIFY_READ, addr, 8)) 1891 goto sigbus; 1892 1893 LoadDW(addr, value, res); 1894 if (res) 1895 goto fault; 1896 regs->regs[reg] = value; 1897 goto success; 1898 #endif /* CONFIG_64BIT */ 1899 1900 /* Cannot handle 64-bit instructions in 32-bit kernel */ 1901 goto sigill; 1902 1903 storeHW: 1904 if (!access_ok(VERIFY_WRITE, addr, 2)) 1905 goto sigbus; 1906 1907 value = regs->regs[reg]; 1908 StoreHW(addr, value, res); 1909 if (res) 1910 goto fault; 1911 goto success; 1912 1913 storeW: 1914 if (!access_ok(VERIFY_WRITE, addr, 4)) 1915 goto sigbus; 1916 1917 value = regs->regs[reg]; 1918 StoreW(addr, value, res); 1919 if (res) 1920 goto fault; 1921 goto success; 1922 1923 storeDW: 1924 #ifdef CONFIG_64BIT 1925 /* 1926 * A 32-bit kernel might be running on a 64-bit processor. But 1927 * if we're on a 32-bit processor and an i-cache incoherency 1928 * or race makes us see a 64-bit instruction here the sdl/sdr 1929 * would blow up, so for now we don't handle unaligned 64-bit 1930 * instructions on 32-bit kernels. 1931 */ 1932 if (!access_ok(VERIFY_WRITE, addr, 8)) 1933 goto sigbus; 1934 1935 value = regs->regs[reg]; 1936 StoreDW(addr, value, res); 1937 if (res) 1938 goto fault; 1939 goto success; 1940 #endif /* CONFIG_64BIT */ 1941 1942 /* Cannot handle 64-bit instructions in 32-bit kernel */ 1943 goto sigill; 1944 1945 success: 1946 regs->cp0_epc = contpc; /* advance or branch */ 1947 1948 #ifdef CONFIG_DEBUG_FS 1949 unaligned_instructions++; 1950 #endif 1951 return; 1952 1953 fault: 1954 /* roll back jump/branch */ 1955 regs->cp0_epc = origpc; 1956 regs->regs[31] = orig31; 1957 /* Did we have an exception handler installed? */ 1958 if (fixup_exception(regs)) 1959 return; 1960 1961 die_if_kernel("Unhandled kernel unaligned access", regs); 1962 force_sig(SIGSEGV, current); 1963 1964 return; 1965 1966 sigbus: 1967 die_if_kernel("Unhandled kernel unaligned access", regs); 1968 force_sig(SIGBUS, current); 1969 1970 return; 1971 1972 sigill: 1973 die_if_kernel 1974 ("Unhandled kernel unaligned access or invalid instruction", regs); 1975 force_sig(SIGILL, current); 1976 } 1977 1978 static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr) 1979 { 1980 unsigned long value; 1981 unsigned int res; 1982 int reg; 1983 unsigned long orig31; 1984 u16 __user *pc16; 1985 unsigned long origpc; 1986 union mips16e_instruction mips16inst, oldinst; 1987 1988 origpc = regs->cp0_epc; 1989 orig31 = regs->regs[31]; 1990 pc16 = (unsigned short __user *)msk_isa16_mode(origpc); 1991 /* 1992 * This load never faults. 1993 */ 1994 __get_user(mips16inst.full, pc16); 1995 oldinst = mips16inst; 1996 1997 /* skip EXTEND instruction */ 1998 if (mips16inst.ri.opcode == MIPS16e_extend_op) { 1999 pc16++; 2000 __get_user(mips16inst.full, pc16); 2001 } else if (delay_slot(regs)) { 2002 /* skip jump instructions */ 2003 /* JAL/JALX are 32 bits but have OPCODE in first short int */ 2004 if (mips16inst.ri.opcode == MIPS16e_jal_op) 2005 pc16++; 2006 pc16++; 2007 if (get_user(mips16inst.full, pc16)) 2008 goto sigbus; 2009 } 2010 2011 switch (mips16inst.ri.opcode) { 2012 case MIPS16e_i64_op: /* I64 or RI64 instruction */ 2013 switch (mips16inst.i64.func) { /* I64/RI64 func field check */ 2014 case MIPS16e_ldpc_func: 2015 case MIPS16e_ldsp_func: 2016 reg = reg16to32[mips16inst.ri64.ry]; 2017 goto loadDW; 2018 2019 case MIPS16e_sdsp_func: 2020 reg = reg16to32[mips16inst.ri64.ry]; 2021 goto writeDW; 2022 2023 case MIPS16e_sdrasp_func: 2024 reg = 29; /* GPRSP */ 2025 goto writeDW; 2026 } 2027 2028 goto sigbus; 2029 2030 case MIPS16e_swsp_op: 2031 case MIPS16e_lwpc_op: 2032 case MIPS16e_lwsp_op: 2033 reg = reg16to32[mips16inst.ri.rx]; 2034 break; 2035 2036 case MIPS16e_i8_op: 2037 if (mips16inst.i8.func != MIPS16e_swrasp_func) 2038 goto sigbus; 2039 reg = 29; /* GPRSP */ 2040 break; 2041 2042 default: 2043 reg = reg16to32[mips16inst.rri.ry]; 2044 break; 2045 } 2046 2047 switch (mips16inst.ri.opcode) { 2048 2049 case MIPS16e_lb_op: 2050 case MIPS16e_lbu_op: 2051 case MIPS16e_sb_op: 2052 goto sigbus; 2053 2054 case MIPS16e_lh_op: 2055 if (!access_ok(VERIFY_READ, addr, 2)) 2056 goto sigbus; 2057 2058 LoadHW(addr, value, res); 2059 if (res) 2060 goto fault; 2061 MIPS16e_compute_return_epc(regs, &oldinst); 2062 regs->regs[reg] = value; 2063 break; 2064 2065 case MIPS16e_lhu_op: 2066 if (!access_ok(VERIFY_READ, addr, 2)) 2067 goto sigbus; 2068 2069 LoadHWU(addr, value, res); 2070 if (res) 2071 goto fault; 2072 MIPS16e_compute_return_epc(regs, &oldinst); 2073 regs->regs[reg] = value; 2074 break; 2075 2076 case MIPS16e_lw_op: 2077 case MIPS16e_lwpc_op: 2078 case MIPS16e_lwsp_op: 2079 if (!access_ok(VERIFY_READ, addr, 4)) 2080 goto sigbus; 2081 2082 LoadW(addr, value, res); 2083 if (res) 2084 goto fault; 2085 MIPS16e_compute_return_epc(regs, &oldinst); 2086 regs->regs[reg] = value; 2087 break; 2088 2089 case MIPS16e_lwu_op: 2090 #ifdef CONFIG_64BIT 2091 /* 2092 * A 32-bit kernel might be running on a 64-bit processor. But 2093 * if we're on a 32-bit processor and an i-cache incoherency 2094 * or race makes us see a 64-bit instruction here the sdl/sdr 2095 * would blow up, so for now we don't handle unaligned 64-bit 2096 * instructions on 32-bit kernels. 2097 */ 2098 if (!access_ok(VERIFY_READ, addr, 4)) 2099 goto sigbus; 2100 2101 LoadWU(addr, value, res); 2102 if (res) 2103 goto fault; 2104 MIPS16e_compute_return_epc(regs, &oldinst); 2105 regs->regs[reg] = value; 2106 break; 2107 #endif /* CONFIG_64BIT */ 2108 2109 /* Cannot handle 64-bit instructions in 32-bit kernel */ 2110 goto sigill; 2111 2112 case MIPS16e_ld_op: 2113 loadDW: 2114 #ifdef CONFIG_64BIT 2115 /* 2116 * A 32-bit kernel might be running on a 64-bit processor. But 2117 * if we're on a 32-bit processor and an i-cache incoherency 2118 * or race makes us see a 64-bit instruction here the sdl/sdr 2119 * would blow up, so for now we don't handle unaligned 64-bit 2120 * instructions on 32-bit kernels. 2121 */ 2122 if (!access_ok(VERIFY_READ, addr, 8)) 2123 goto sigbus; 2124 2125 LoadDW(addr, value, res); 2126 if (res) 2127 goto fault; 2128 MIPS16e_compute_return_epc(regs, &oldinst); 2129 regs->regs[reg] = value; 2130 break; 2131 #endif /* CONFIG_64BIT */ 2132 2133 /* Cannot handle 64-bit instructions in 32-bit kernel */ 2134 goto sigill; 2135 2136 case MIPS16e_sh_op: 2137 if (!access_ok(VERIFY_WRITE, addr, 2)) 2138 goto sigbus; 2139 2140 MIPS16e_compute_return_epc(regs, &oldinst); 2141 value = regs->regs[reg]; 2142 StoreHW(addr, value, res); 2143 if (res) 2144 goto fault; 2145 break; 2146 2147 case MIPS16e_sw_op: 2148 case MIPS16e_swsp_op: 2149 case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */ 2150 if (!access_ok(VERIFY_WRITE, addr, 4)) 2151 goto sigbus; 2152 2153 MIPS16e_compute_return_epc(regs, &oldinst); 2154 value = regs->regs[reg]; 2155 StoreW(addr, value, res); 2156 if (res) 2157 goto fault; 2158 break; 2159 2160 case MIPS16e_sd_op: 2161 writeDW: 2162 #ifdef CONFIG_64BIT 2163 /* 2164 * A 32-bit kernel might be running on a 64-bit processor. But 2165 * if we're on a 32-bit processor and an i-cache incoherency 2166 * or race makes us see a 64-bit instruction here the sdl/sdr 2167 * would blow up, so for now we don't handle unaligned 64-bit 2168 * instructions on 32-bit kernels. 2169 */ 2170 if (!access_ok(VERIFY_WRITE, addr, 8)) 2171 goto sigbus; 2172 2173 MIPS16e_compute_return_epc(regs, &oldinst); 2174 value = regs->regs[reg]; 2175 StoreDW(addr, value, res); 2176 if (res) 2177 goto fault; 2178 break; 2179 #endif /* CONFIG_64BIT */ 2180 2181 /* Cannot handle 64-bit instructions in 32-bit kernel */ 2182 goto sigill; 2183 2184 default: 2185 /* 2186 * Pheeee... We encountered an yet unknown instruction or 2187 * cache coherence problem. Die sucker, die ... 2188 */ 2189 goto sigill; 2190 } 2191 2192 #ifdef CONFIG_DEBUG_FS 2193 unaligned_instructions++; 2194 #endif 2195 2196 return; 2197 2198 fault: 2199 /* roll back jump/branch */ 2200 regs->cp0_epc = origpc; 2201 regs->regs[31] = orig31; 2202 /* Did we have an exception handler installed? */ 2203 if (fixup_exception(regs)) 2204 return; 2205 2206 die_if_kernel("Unhandled kernel unaligned access", regs); 2207 force_sig(SIGSEGV, current); 2208 2209 return; 2210 2211 sigbus: 2212 die_if_kernel("Unhandled kernel unaligned access", regs); 2213 force_sig(SIGBUS, current); 2214 2215 return; 2216 2217 sigill: 2218 die_if_kernel 2219 ("Unhandled kernel unaligned access or invalid instruction", regs); 2220 force_sig(SIGILL, current); 2221 } 2222 2223 asmlinkage void do_ade(struct pt_regs *regs) 2224 { 2225 enum ctx_state prev_state; 2226 unsigned int __user *pc; 2227 mm_segment_t seg; 2228 2229 prev_state = exception_enter(); 2230 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 2231 1, regs, regs->cp0_badvaddr); 2232 /* 2233 * Did we catch a fault trying to load an instruction? 2234 */ 2235 if (regs->cp0_badvaddr == regs->cp0_epc) 2236 goto sigbus; 2237 2238 if (user_mode(regs) && !test_thread_flag(TIF_FIXADE)) 2239 goto sigbus; 2240 if (unaligned_action == UNALIGNED_ACTION_SIGNAL) 2241 goto sigbus; 2242 2243 /* 2244 * Do branch emulation only if we didn't forward the exception. 2245 * This is all so but ugly ... 2246 */ 2247 2248 /* 2249 * Are we running in microMIPS mode? 2250 */ 2251 if (get_isa16_mode(regs->cp0_epc)) { 2252 /* 2253 * Did we catch a fault trying to load an instruction in 2254 * 16-bit mode? 2255 */ 2256 if (regs->cp0_badvaddr == msk_isa16_mode(regs->cp0_epc)) 2257 goto sigbus; 2258 if (unaligned_action == UNALIGNED_ACTION_SHOW) 2259 show_registers(regs); 2260 2261 if (cpu_has_mmips) { 2262 seg = get_fs(); 2263 if (!user_mode(regs)) 2264 set_fs(KERNEL_DS); 2265 emulate_load_store_microMIPS(regs, 2266 (void __user *)regs->cp0_badvaddr); 2267 set_fs(seg); 2268 2269 return; 2270 } 2271 2272 if (cpu_has_mips16) { 2273 seg = get_fs(); 2274 if (!user_mode(regs)) 2275 set_fs(KERNEL_DS); 2276 emulate_load_store_MIPS16e(regs, 2277 (void __user *)regs->cp0_badvaddr); 2278 set_fs(seg); 2279 2280 return; 2281 } 2282 2283 goto sigbus; 2284 } 2285 2286 if (unaligned_action == UNALIGNED_ACTION_SHOW) 2287 show_registers(regs); 2288 pc = (unsigned int __user *)exception_epc(regs); 2289 2290 seg = get_fs(); 2291 if (!user_mode(regs)) 2292 set_fs(KERNEL_DS); 2293 emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc); 2294 set_fs(seg); 2295 2296 return; 2297 2298 sigbus: 2299 die_if_kernel("Kernel unaligned instruction access", regs); 2300 force_sig(SIGBUS, current); 2301 2302 /* 2303 * XXX On return from the signal handler we should advance the epc 2304 */ 2305 exception_exit(prev_state); 2306 } 2307 2308 #ifdef CONFIG_DEBUG_FS 2309 static int __init debugfs_unaligned(void) 2310 { 2311 struct dentry *d; 2312 2313 if (!mips_debugfs_dir) 2314 return -ENODEV; 2315 d = debugfs_create_u32("unaligned_instructions", S_IRUGO, 2316 mips_debugfs_dir, &unaligned_instructions); 2317 if (!d) 2318 return -ENOMEM; 2319 d = debugfs_create_u32("unaligned_action", S_IRUGO | S_IWUSR, 2320 mips_debugfs_dir, &unaligned_action); 2321 if (!d) 2322 return -ENOMEM; 2323 return 0; 2324 } 2325 arch_initcall(debugfs_unaligned); 2326 #endif 2327