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/mmu_context.h>
93 #include <linux/uaccess.h>
94
95 #define STR(x) __STR(x)
96 #define __STR(x) #x
97
98 enum {
99 UNALIGNED_ACTION_QUIET,
100 UNALIGNED_ACTION_SIGNAL,
101 UNALIGNED_ACTION_SHOW,
102 };
103 #ifdef CONFIG_DEBUG_FS
104 static u32 unaligned_instructions;
105 static u32 unaligned_action;
106 #else
107 #define unaligned_action UNALIGNED_ACTION_QUIET
108 #endif
109 extern void show_registers(struct pt_regs *regs);
110
111 #ifdef __BIG_ENDIAN
112 #define _LoadHW(addr, value, res, type) \
113 do { \
114 __asm__ __volatile__ (".set\tnoat\n" \
115 "1:\t"type##_lb("%0", "0(%2)")"\n" \
116 "2:\t"type##_lbu("$1", "1(%2)")"\n\t"\
117 "sll\t%0, 0x8\n\t" \
118 "or\t%0, $1\n\t" \
119 "li\t%1, 0\n" \
120 "3:\t.set\tat\n\t" \
121 ".insn\n\t" \
122 ".section\t.fixup,\"ax\"\n\t" \
123 "4:\tli\t%1, %3\n\t" \
124 "j\t3b\n\t" \
125 ".previous\n\t" \
126 ".section\t__ex_table,\"a\"\n\t" \
127 STR(PTR)"\t1b, 4b\n\t" \
128 STR(PTR)"\t2b, 4b\n\t" \
129 ".previous" \
130 : "=&r" (value), "=r" (res) \
131 : "r" (addr), "i" (-EFAULT)); \
132 } while(0)
133
134 #ifdef CONFIG_CPU_HAS_LOAD_STORE_LR
135 #define _LoadW(addr, value, res, type) \
136 do { \
137 __asm__ __volatile__ ( \
138 "1:\t"type##_lwl("%0", "(%2)")"\n" \
139 "2:\t"type##_lwr("%0", "3(%2)")"\n\t"\
140 "li\t%1, 0\n" \
141 "3:\n\t" \
142 ".insn\n\t" \
143 ".section\t.fixup,\"ax\"\n\t" \
144 "4:\tli\t%1, %3\n\t" \
145 "j\t3b\n\t" \
146 ".previous\n\t" \
147 ".section\t__ex_table,\"a\"\n\t" \
148 STR(PTR)"\t1b, 4b\n\t" \
149 STR(PTR)"\t2b, 4b\n\t" \
150 ".previous" \
151 : "=&r" (value), "=r" (res) \
152 : "r" (addr), "i" (-EFAULT)); \
153 } while(0)
154
155 #else /* !CONFIG_CPU_HAS_LOAD_STORE_LR */
156 /* For CPUs without lwl instruction */
157 #define _LoadW(addr, value, res, type) \
158 do { \
159 __asm__ __volatile__ ( \
160 ".set\tpush\n" \
161 ".set\tnoat\n\t" \
162 "1:"type##_lb("%0", "0(%2)")"\n\t" \
163 "2:"type##_lbu("$1", "1(%2)")"\n\t" \
164 "sll\t%0, 0x8\n\t" \
165 "or\t%0, $1\n\t" \
166 "3:"type##_lbu("$1", "2(%2)")"\n\t" \
167 "sll\t%0, 0x8\n\t" \
168 "or\t%0, $1\n\t" \
169 "4:"type##_lbu("$1", "3(%2)")"\n\t" \
170 "sll\t%0, 0x8\n\t" \
171 "or\t%0, $1\n\t" \
172 "li\t%1, 0\n" \
173 ".set\tpop\n" \
174 "10:\n\t" \
175 ".insn\n\t" \
176 ".section\t.fixup,\"ax\"\n\t" \
177 "11:\tli\t%1, %3\n\t" \
178 "j\t10b\n\t" \
179 ".previous\n\t" \
180 ".section\t__ex_table,\"a\"\n\t" \
181 STR(PTR)"\t1b, 11b\n\t" \
182 STR(PTR)"\t2b, 11b\n\t" \
183 STR(PTR)"\t3b, 11b\n\t" \
184 STR(PTR)"\t4b, 11b\n\t" \
185 ".previous" \
186 : "=&r" (value), "=r" (res) \
187 : "r" (addr), "i" (-EFAULT)); \
188 } while(0)
189
190 #endif /* !CONFIG_CPU_HAS_LOAD_STORE_LR */
191
192 #define _LoadHWU(addr, value, res, type) \
193 do { \
194 __asm__ __volatile__ ( \
195 ".set\tnoat\n" \
196 "1:\t"type##_lbu("%0", "0(%2)")"\n" \
197 "2:\t"type##_lbu("$1", "1(%2)")"\n\t"\
198 "sll\t%0, 0x8\n\t" \
199 "or\t%0, $1\n\t" \
200 "li\t%1, 0\n" \
201 "3:\n\t" \
202 ".insn\n\t" \
203 ".set\tat\n\t" \
204 ".section\t.fixup,\"ax\"\n\t" \
205 "4:\tli\t%1, %3\n\t" \
206 "j\t3b\n\t" \
207 ".previous\n\t" \
208 ".section\t__ex_table,\"a\"\n\t" \
209 STR(PTR)"\t1b, 4b\n\t" \
210 STR(PTR)"\t2b, 4b\n\t" \
211 ".previous" \
212 : "=&r" (value), "=r" (res) \
213 : "r" (addr), "i" (-EFAULT)); \
214 } while(0)
215
216 #ifdef CONFIG_CPU_HAS_LOAD_STORE_LR
217 #define _LoadWU(addr, value, res, type) \
218 do { \
219 __asm__ __volatile__ ( \
220 "1:\t"type##_lwl("%0", "(%2)")"\n" \
221 "2:\t"type##_lwr("%0", "3(%2)")"\n\t"\
222 "dsll\t%0, %0, 32\n\t" \
223 "dsrl\t%0, %0, 32\n\t" \
224 "li\t%1, 0\n" \
225 "3:\n\t" \
226 ".insn\n\t" \
227 "\t.section\t.fixup,\"ax\"\n\t" \
228 "4:\tli\t%1, %3\n\t" \
229 "j\t3b\n\t" \
230 ".previous\n\t" \
231 ".section\t__ex_table,\"a\"\n\t" \
232 STR(PTR)"\t1b, 4b\n\t" \
233 STR(PTR)"\t2b, 4b\n\t" \
234 ".previous" \
235 : "=&r" (value), "=r" (res) \
236 : "r" (addr), "i" (-EFAULT)); \
237 } while(0)
238
239 #define _LoadDW(addr, value, res) \
240 do { \
241 __asm__ __volatile__ ( \
242 "1:\tldl\t%0, (%2)\n" \
243 "2:\tldr\t%0, 7(%2)\n\t" \
244 "li\t%1, 0\n" \
245 "3:\n\t" \
246 ".insn\n\t" \
247 "\t.section\t.fixup,\"ax\"\n\t" \
248 "4:\tli\t%1, %3\n\t" \
249 "j\t3b\n\t" \
250 ".previous\n\t" \
251 ".section\t__ex_table,\"a\"\n\t" \
252 STR(PTR)"\t1b, 4b\n\t" \
253 STR(PTR)"\t2b, 4b\n\t" \
254 ".previous" \
255 : "=&r" (value), "=r" (res) \
256 : "r" (addr), "i" (-EFAULT)); \
257 } while(0)
258
259 #else /* !CONFIG_CPU_HAS_LOAD_STORE_LR */
260 /* For CPUs without lwl and ldl instructions */
261 #define _LoadWU(addr, value, res, type) \
262 do { \
263 __asm__ __volatile__ ( \
264 ".set\tpush\n\t" \
265 ".set\tnoat\n\t" \
266 "1:"type##_lbu("%0", "0(%2)")"\n\t" \
267 "2:"type##_lbu("$1", "1(%2)")"\n\t" \
268 "sll\t%0, 0x8\n\t" \
269 "or\t%0, $1\n\t" \
270 "3:"type##_lbu("$1", "2(%2)")"\n\t" \
271 "sll\t%0, 0x8\n\t" \
272 "or\t%0, $1\n\t" \
273 "4:"type##_lbu("$1", "3(%2)")"\n\t" \
274 "sll\t%0, 0x8\n\t" \
275 "or\t%0, $1\n\t" \
276 "li\t%1, 0\n" \
277 ".set\tpop\n" \
278 "10:\n\t" \
279 ".insn\n\t" \
280 ".section\t.fixup,\"ax\"\n\t" \
281 "11:\tli\t%1, %3\n\t" \
282 "j\t10b\n\t" \
283 ".previous\n\t" \
284 ".section\t__ex_table,\"a\"\n\t" \
285 STR(PTR)"\t1b, 11b\n\t" \
286 STR(PTR)"\t2b, 11b\n\t" \
287 STR(PTR)"\t3b, 11b\n\t" \
288 STR(PTR)"\t4b, 11b\n\t" \
289 ".previous" \
290 : "=&r" (value), "=r" (res) \
291 : "r" (addr), "i" (-EFAULT)); \
292 } while(0)
293
294 #define _LoadDW(addr, value, res) \
295 do { \
296 __asm__ __volatile__ ( \
297 ".set\tpush\n\t" \
298 ".set\tnoat\n\t" \
299 "1:lb\t%0, 0(%2)\n\t" \
300 "2:lbu\t $1, 1(%2)\n\t" \
301 "dsll\t%0, 0x8\n\t" \
302 "or\t%0, $1\n\t" \
303 "3:lbu\t$1, 2(%2)\n\t" \
304 "dsll\t%0, 0x8\n\t" \
305 "or\t%0, $1\n\t" \
306 "4:lbu\t$1, 3(%2)\n\t" \
307 "dsll\t%0, 0x8\n\t" \
308 "or\t%0, $1\n\t" \
309 "5:lbu\t$1, 4(%2)\n\t" \
310 "dsll\t%0, 0x8\n\t" \
311 "or\t%0, $1\n\t" \
312 "6:lbu\t$1, 5(%2)\n\t" \
313 "dsll\t%0, 0x8\n\t" \
314 "or\t%0, $1\n\t" \
315 "7:lbu\t$1, 6(%2)\n\t" \
316 "dsll\t%0, 0x8\n\t" \
317 "or\t%0, $1\n\t" \
318 "8:lbu\t$1, 7(%2)\n\t" \
319 "dsll\t%0, 0x8\n\t" \
320 "or\t%0, $1\n\t" \
321 "li\t%1, 0\n" \
322 ".set\tpop\n\t" \
323 "10:\n\t" \
324 ".insn\n\t" \
325 ".section\t.fixup,\"ax\"\n\t" \
326 "11:\tli\t%1, %3\n\t" \
327 "j\t10b\n\t" \
328 ".previous\n\t" \
329 ".section\t__ex_table,\"a\"\n\t" \
330 STR(PTR)"\t1b, 11b\n\t" \
331 STR(PTR)"\t2b, 11b\n\t" \
332 STR(PTR)"\t3b, 11b\n\t" \
333 STR(PTR)"\t4b, 11b\n\t" \
334 STR(PTR)"\t5b, 11b\n\t" \
335 STR(PTR)"\t6b, 11b\n\t" \
336 STR(PTR)"\t7b, 11b\n\t" \
337 STR(PTR)"\t8b, 11b\n\t" \
338 ".previous" \
339 : "=&r" (value), "=r" (res) \
340 : "r" (addr), "i" (-EFAULT)); \
341 } while(0)
342
343 #endif /* !CONFIG_CPU_HAS_LOAD_STORE_LR */
344
345
346 #define _StoreHW(addr, value, res, type) \
347 do { \
348 __asm__ __volatile__ ( \
349 ".set\tnoat\n" \
350 "1:\t"type##_sb("%1", "1(%2)")"\n" \
351 "srl\t$1, %1, 0x8\n" \
352 "2:\t"type##_sb("$1", "0(%2)")"\n" \
353 ".set\tat\n\t" \
354 "li\t%0, 0\n" \
355 "3:\n\t" \
356 ".insn\n\t" \
357 ".section\t.fixup,\"ax\"\n\t" \
358 "4:\tli\t%0, %3\n\t" \
359 "j\t3b\n\t" \
360 ".previous\n\t" \
361 ".section\t__ex_table,\"a\"\n\t" \
362 STR(PTR)"\t1b, 4b\n\t" \
363 STR(PTR)"\t2b, 4b\n\t" \
364 ".previous" \
365 : "=r" (res) \
366 : "r" (value), "r" (addr), "i" (-EFAULT));\
367 } while(0)
368
369 #ifdef CONFIG_CPU_HAS_LOAD_STORE_LR
370 #define _StoreW(addr, value, res, type) \
371 do { \
372 __asm__ __volatile__ ( \
373 "1:\t"type##_swl("%1", "(%2)")"\n" \
374 "2:\t"type##_swr("%1", "3(%2)")"\n\t"\
375 "li\t%0, 0\n" \
376 "3:\n\t" \
377 ".insn\n\t" \
378 ".section\t.fixup,\"ax\"\n\t" \
379 "4:\tli\t%0, %3\n\t" \
380 "j\t3b\n\t" \
381 ".previous\n\t" \
382 ".section\t__ex_table,\"a\"\n\t" \
383 STR(PTR)"\t1b, 4b\n\t" \
384 STR(PTR)"\t2b, 4b\n\t" \
385 ".previous" \
386 : "=r" (res) \
387 : "r" (value), "r" (addr), "i" (-EFAULT)); \
388 } while(0)
389
390 #define _StoreDW(addr, value, res) \
391 do { \
392 __asm__ __volatile__ ( \
393 "1:\tsdl\t%1,(%2)\n" \
394 "2:\tsdr\t%1, 7(%2)\n\t" \
395 "li\t%0, 0\n" \
396 "3:\n\t" \
397 ".insn\n\t" \
398 ".section\t.fixup,\"ax\"\n\t" \
399 "4:\tli\t%0, %3\n\t" \
400 "j\t3b\n\t" \
401 ".previous\n\t" \
402 ".section\t__ex_table,\"a\"\n\t" \
403 STR(PTR)"\t1b, 4b\n\t" \
404 STR(PTR)"\t2b, 4b\n\t" \
405 ".previous" \
406 : "=r" (res) \
407 : "r" (value), "r" (addr), "i" (-EFAULT)); \
408 } while(0)
409
410 #else /* !CONFIG_CPU_HAS_LOAD_STORE_LR */
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_HAS_LOAD_STORE_LR */
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 #ifdef CONFIG_CPU_HAS_LOAD_STORE_LR
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 /* !CONFIG_CPU_HAS_LOAD_STORE_LR */
534 /* For CPUs without 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_HAS_LOAD_STORE_LR */
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 #ifdef CONFIG_CPU_HAS_LOAD_STORE_LR
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 /* !CONFIG_CPU_HAS_LOAD_STORE_LR */
639 /* For CPUs without 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_HAS_LOAD_STORE_LR */
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 #ifdef CONFIG_CPU_HAS_LOAD_STORE_LR
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 /* !CONFIG_CPU_HAS_LOAD_STORE_LR */
788 /* For CPUs without 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_HAS_LOAD_STORE_LR */
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 unsigned long origpc, orig31, value;
887 union mips_instruction insn;
888 unsigned int res;
889 #ifdef CONFIG_EVA
890 mm_segment_t seg;
891 #endif
892 origpc = (unsigned long)pc;
893 orig31 = regs->regs[31];
894
895 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
896
897 /*
898 * This load never faults.
899 */
900 __get_user(insn.word, pc);
901
902 switch (insn.i_format.opcode) {
903 /*
904 * These are instructions that a compiler doesn't generate. We
905 * can assume therefore that the code is MIPS-aware and
906 * really buggy. Emulating these instructions would break the
907 * semantics anyway.
908 */
909 case ll_op:
910 case lld_op:
911 case sc_op:
912 case scd_op:
913
914 /*
915 * For these instructions the only way to create an address
916 * error is an attempted access to kernel/supervisor address
917 * space.
918 */
919 case ldl_op:
920 case ldr_op:
921 case lwl_op:
922 case lwr_op:
923 case sdl_op:
924 case sdr_op:
925 case swl_op:
926 case swr_op:
927 case lb_op:
928 case lbu_op:
929 case sb_op:
930 goto sigbus;
931
932 /*
933 * The remaining opcodes are the ones that are really of
934 * interest.
935 */
936 case spec3_op:
937 if (insn.dsp_format.func == lx_op) {
938 switch (insn.dsp_format.op) {
939 case lwx_op:
940 if (!access_ok(addr, 4))
941 goto sigbus;
942 LoadW(addr, value, res);
943 if (res)
944 goto fault;
945 compute_return_epc(regs);
946 regs->regs[insn.dsp_format.rd] = value;
947 break;
948 case lhx_op:
949 if (!access_ok(addr, 2))
950 goto sigbus;
951 LoadHW(addr, value, res);
952 if (res)
953 goto fault;
954 compute_return_epc(regs);
955 regs->regs[insn.dsp_format.rd] = value;
956 break;
957 default:
958 goto sigill;
959 }
960 }
961 #ifdef CONFIG_EVA
962 else {
963 /*
964 * we can land here only from kernel accessing user
965 * memory, so we need to "switch" the address limit to
966 * user space, so that address check can work properly.
967 */
968 seg = get_fs();
969 set_fs(USER_DS);
970 switch (insn.spec3_format.func) {
971 case lhe_op:
972 if (!access_ok(addr, 2)) {
973 set_fs(seg);
974 goto sigbus;
975 }
976 LoadHWE(addr, value, res);
977 if (res) {
978 set_fs(seg);
979 goto fault;
980 }
981 compute_return_epc(regs);
982 regs->regs[insn.spec3_format.rt] = value;
983 break;
984 case lwe_op:
985 if (!access_ok(addr, 4)) {
986 set_fs(seg);
987 goto sigbus;
988 }
989 LoadWE(addr, value, res);
990 if (res) {
991 set_fs(seg);
992 goto fault;
993 }
994 compute_return_epc(regs);
995 regs->regs[insn.spec3_format.rt] = value;
996 break;
997 case lhue_op:
998 if (!access_ok(addr, 2)) {
999 set_fs(seg);
1000 goto sigbus;
1001 }
1002 LoadHWUE(addr, value, res);
1003 if (res) {
1004 set_fs(seg);
1005 goto fault;
1006 }
1007 compute_return_epc(regs);
1008 regs->regs[insn.spec3_format.rt] = value;
1009 break;
1010 case she_op:
1011 if (!access_ok(addr, 2)) {
1012 set_fs(seg);
1013 goto sigbus;
1014 }
1015 compute_return_epc(regs);
1016 value = regs->regs[insn.spec3_format.rt];
1017 StoreHWE(addr, value, res);
1018 if (res) {
1019 set_fs(seg);
1020 goto fault;
1021 }
1022 break;
1023 case swe_op:
1024 if (!access_ok(addr, 4)) {
1025 set_fs(seg);
1026 goto sigbus;
1027 }
1028 compute_return_epc(regs);
1029 value = regs->regs[insn.spec3_format.rt];
1030 StoreWE(addr, value, res);
1031 if (res) {
1032 set_fs(seg);
1033 goto fault;
1034 }
1035 break;
1036 default:
1037 set_fs(seg);
1038 goto sigill;
1039 }
1040 set_fs(seg);
1041 }
1042 #endif
1043 break;
1044 case lh_op:
1045 if (!access_ok(addr, 2))
1046 goto sigbus;
1047
1048 if (IS_ENABLED(CONFIG_EVA)) {
1049 if (uaccess_kernel())
1050 LoadHW(addr, value, res);
1051 else
1052 LoadHWE(addr, value, res);
1053 } else {
1054 LoadHW(addr, value, res);
1055 }
1056
1057 if (res)
1058 goto fault;
1059 compute_return_epc(regs);
1060 regs->regs[insn.i_format.rt] = value;
1061 break;
1062
1063 case lw_op:
1064 if (!access_ok(addr, 4))
1065 goto sigbus;
1066
1067 if (IS_ENABLED(CONFIG_EVA)) {
1068 if (uaccess_kernel())
1069 LoadW(addr, value, res);
1070 else
1071 LoadWE(addr, value, res);
1072 } else {
1073 LoadW(addr, value, res);
1074 }
1075
1076 if (res)
1077 goto fault;
1078 compute_return_epc(regs);
1079 regs->regs[insn.i_format.rt] = value;
1080 break;
1081
1082 case lhu_op:
1083 if (!access_ok(addr, 2))
1084 goto sigbus;
1085
1086 if (IS_ENABLED(CONFIG_EVA)) {
1087 if (uaccess_kernel())
1088 LoadHWU(addr, value, res);
1089 else
1090 LoadHWUE(addr, value, res);
1091 } else {
1092 LoadHWU(addr, value, res);
1093 }
1094
1095 if (res)
1096 goto fault;
1097 compute_return_epc(regs);
1098 regs->regs[insn.i_format.rt] = value;
1099 break;
1100
1101 case lwu_op:
1102 #ifdef CONFIG_64BIT
1103 /*
1104 * A 32-bit kernel might be running on a 64-bit processor. But
1105 * if we're on a 32-bit processor and an i-cache incoherency
1106 * or race makes us see a 64-bit instruction here the sdl/sdr
1107 * would blow up, so for now we don't handle unaligned 64-bit
1108 * instructions on 32-bit kernels.
1109 */
1110 if (!access_ok(addr, 4))
1111 goto sigbus;
1112
1113 LoadWU(addr, value, res);
1114 if (res)
1115 goto fault;
1116 compute_return_epc(regs);
1117 regs->regs[insn.i_format.rt] = value;
1118 break;
1119 #endif /* CONFIG_64BIT */
1120
1121 /* Cannot handle 64-bit instructions in 32-bit kernel */
1122 goto sigill;
1123
1124 case ld_op:
1125 #ifdef CONFIG_64BIT
1126 /*
1127 * A 32-bit kernel might be running on a 64-bit processor. But
1128 * if we're on a 32-bit processor and an i-cache incoherency
1129 * or race makes us see a 64-bit instruction here the sdl/sdr
1130 * would blow up, so for now we don't handle unaligned 64-bit
1131 * instructions on 32-bit kernels.
1132 */
1133 if (!access_ok(addr, 8))
1134 goto sigbus;
1135
1136 LoadDW(addr, value, res);
1137 if (res)
1138 goto fault;
1139 compute_return_epc(regs);
1140 regs->regs[insn.i_format.rt] = value;
1141 break;
1142 #endif /* CONFIG_64BIT */
1143
1144 /* Cannot handle 64-bit instructions in 32-bit kernel */
1145 goto sigill;
1146
1147 case sh_op:
1148 if (!access_ok(addr, 2))
1149 goto sigbus;
1150
1151 compute_return_epc(regs);
1152 value = regs->regs[insn.i_format.rt];
1153
1154 if (IS_ENABLED(CONFIG_EVA)) {
1155 if (uaccess_kernel())
1156 StoreHW(addr, value, res);
1157 else
1158 StoreHWE(addr, value, res);
1159 } else {
1160 StoreHW(addr, value, res);
1161 }
1162
1163 if (res)
1164 goto fault;
1165 break;
1166
1167 case sw_op:
1168 if (!access_ok(addr, 4))
1169 goto sigbus;
1170
1171 compute_return_epc(regs);
1172 value = regs->regs[insn.i_format.rt];
1173
1174 if (IS_ENABLED(CONFIG_EVA)) {
1175 if (uaccess_kernel())
1176 StoreW(addr, value, res);
1177 else
1178 StoreWE(addr, value, res);
1179 } else {
1180 StoreW(addr, value, res);
1181 }
1182
1183 if (res)
1184 goto fault;
1185 break;
1186
1187 case sd_op:
1188 #ifdef CONFIG_64BIT
1189 /*
1190 * A 32-bit kernel might be running on a 64-bit processor. But
1191 * if we're on a 32-bit processor and an i-cache incoherency
1192 * or race makes us see a 64-bit instruction here the sdl/sdr
1193 * would blow up, so for now we don't handle unaligned 64-bit
1194 * instructions on 32-bit kernels.
1195 */
1196 if (!access_ok(addr, 8))
1197 goto sigbus;
1198
1199 compute_return_epc(regs);
1200 value = regs->regs[insn.i_format.rt];
1201 StoreDW(addr, value, res);
1202 if (res)
1203 goto fault;
1204 break;
1205 #endif /* CONFIG_64BIT */
1206
1207 /* Cannot handle 64-bit instructions in 32-bit kernel */
1208 goto sigill;
1209
1210 #ifdef CONFIG_MIPS_FP_SUPPORT
1211
1212 case lwc1_op:
1213 case ldc1_op:
1214 case swc1_op:
1215 case sdc1_op:
1216 case cop1x_op: {
1217 void __user *fault_addr = NULL;
1218
1219 die_if_kernel("Unaligned FP access in kernel code", regs);
1220 BUG_ON(!used_math());
1221
1222 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
1223 &fault_addr);
1224 own_fpu(1); /* Restore FPU state. */
1225
1226 /* Signal if something went wrong. */
1227 process_fpemu_return(res, fault_addr, 0);
1228
1229 if (res == 0)
1230 break;
1231 return;
1232 }
1233 #endif /* CONFIG_MIPS_FP_SUPPORT */
1234
1235 #ifdef CONFIG_CPU_HAS_MSA
1236
1237 case msa_op: {
1238 unsigned int wd, preempted;
1239 enum msa_2b_fmt df;
1240 union fpureg *fpr;
1241
1242 if (!cpu_has_msa)
1243 goto sigill;
1244
1245 /*
1246 * If we've reached this point then userland should have taken
1247 * the MSA disabled exception & initialised vector context at
1248 * some point in the past.
1249 */
1250 BUG_ON(!thread_msa_context_live());
1251
1252 df = insn.msa_mi10_format.df;
1253 wd = insn.msa_mi10_format.wd;
1254 fpr = ¤t->thread.fpu.fpr[wd];
1255
1256 switch (insn.msa_mi10_format.func) {
1257 case msa_ld_op:
1258 if (!access_ok(addr, sizeof(*fpr)))
1259 goto sigbus;
1260
1261 do {
1262 /*
1263 * If we have live MSA context keep track of
1264 * whether we get preempted in order to avoid
1265 * the register context we load being clobbered
1266 * by the live context as it's saved during
1267 * preemption. If we don't have live context
1268 * then it can't be saved to clobber the value
1269 * we load.
1270 */
1271 preempted = test_thread_flag(TIF_USEDMSA);
1272
1273 res = __copy_from_user_inatomic(fpr, addr,
1274 sizeof(*fpr));
1275 if (res)
1276 goto fault;
1277
1278 /*
1279 * Update the hardware register if it is in use
1280 * by the task in this quantum, in order to
1281 * avoid having to save & restore the whole
1282 * vector context.
1283 */
1284 preempt_disable();
1285 if (test_thread_flag(TIF_USEDMSA)) {
1286 write_msa_wr(wd, fpr, df);
1287 preempted = 0;
1288 }
1289 preempt_enable();
1290 } while (preempted);
1291 break;
1292
1293 case msa_st_op:
1294 if (!access_ok(addr, sizeof(*fpr)))
1295 goto sigbus;
1296
1297 /*
1298 * Update from the hardware register if it is in use by
1299 * the task in this quantum, in order to avoid having to
1300 * save & restore the whole vector context.
1301 */
1302 preempt_disable();
1303 if (test_thread_flag(TIF_USEDMSA))
1304 read_msa_wr(wd, fpr, df);
1305 preempt_enable();
1306
1307 res = __copy_to_user_inatomic(addr, fpr, sizeof(*fpr));
1308 if (res)
1309 goto fault;
1310 break;
1311
1312 default:
1313 goto sigbus;
1314 }
1315
1316 compute_return_epc(regs);
1317 break;
1318 }
1319 #endif /* CONFIG_CPU_HAS_MSA */
1320
1321 #ifndef CONFIG_CPU_MIPSR6
1322 /*
1323 * COP2 is available to implementor for application specific use.
1324 * It's up to applications to register a notifier chain and do
1325 * whatever they have to do, including possible sending of signals.
1326 *
1327 * This instruction has been reallocated in Release 6
1328 */
1329 case lwc2_op:
1330 cu2_notifier_call_chain(CU2_LWC2_OP, regs);
1331 break;
1332
1333 case ldc2_op:
1334 cu2_notifier_call_chain(CU2_LDC2_OP, regs);
1335 break;
1336
1337 case swc2_op:
1338 cu2_notifier_call_chain(CU2_SWC2_OP, regs);
1339 break;
1340
1341 case sdc2_op:
1342 cu2_notifier_call_chain(CU2_SDC2_OP, regs);
1343 break;
1344 #endif
1345 default:
1346 /*
1347 * Pheeee... We encountered an yet unknown instruction or
1348 * cache coherence problem. Die sucker, die ...
1349 */
1350 goto sigill;
1351 }
1352
1353 #ifdef CONFIG_DEBUG_FS
1354 unaligned_instructions++;
1355 #endif
1356
1357 return;
1358
1359 fault:
1360 /* roll back jump/branch */
1361 regs->cp0_epc = origpc;
1362 regs->regs[31] = orig31;
1363 /* Did we have an exception handler installed? */
1364 if (fixup_exception(regs))
1365 return;
1366
1367 die_if_kernel("Unhandled kernel unaligned access", regs);
1368 force_sig(SIGSEGV);
1369
1370 return;
1371
1372 sigbus:
1373 die_if_kernel("Unhandled kernel unaligned access", regs);
1374 force_sig(SIGBUS);
1375
1376 return;
1377
1378 sigill:
1379 die_if_kernel
1380 ("Unhandled kernel unaligned access or invalid instruction", regs);
1381 force_sig(SIGILL);
1382 }
1383
1384 /* Recode table from 16-bit register notation to 32-bit GPR. */
1385 const int reg16to32[] = { 16, 17, 2, 3, 4, 5, 6, 7 };
1386
1387 /* Recode table from 16-bit STORE register notation to 32-bit GPR. */
1388 static const int reg16to32st[] = { 0, 17, 2, 3, 4, 5, 6, 7 };
1389
1390 static void emulate_load_store_microMIPS(struct pt_regs *regs,
1391 void __user *addr)
1392 {
1393 unsigned long value;
1394 unsigned int res;
1395 int i;
1396 unsigned int reg = 0, rvar;
1397 unsigned long orig31;
1398 u16 __user *pc16;
1399 u16 halfword;
1400 unsigned int word;
1401 unsigned long origpc, contpc;
1402 union mips_instruction insn;
1403 struct mm_decoded_insn mminsn;
1404
1405 origpc = regs->cp0_epc;
1406 orig31 = regs->regs[31];
1407
1408 mminsn.micro_mips_mode = 1;
1409
1410 /*
1411 * This load never faults.
1412 */
1413 pc16 = (unsigned short __user *)msk_isa16_mode(regs->cp0_epc);
1414 __get_user(halfword, pc16);
1415 pc16++;
1416 contpc = regs->cp0_epc + 2;
1417 word = ((unsigned int)halfword << 16);
1418 mminsn.pc_inc = 2;
1419
1420 if (!mm_insn_16bit(halfword)) {
1421 __get_user(halfword, pc16);
1422 pc16++;
1423 contpc = regs->cp0_epc + 4;
1424 mminsn.pc_inc = 4;
1425 word |= halfword;
1426 }
1427 mminsn.insn = word;
1428
1429 if (get_user(halfword, pc16))
1430 goto fault;
1431 mminsn.next_pc_inc = 2;
1432 word = ((unsigned int)halfword << 16);
1433
1434 if (!mm_insn_16bit(halfword)) {
1435 pc16++;
1436 if (get_user(halfword, pc16))
1437 goto fault;
1438 mminsn.next_pc_inc = 4;
1439 word |= halfword;
1440 }
1441 mminsn.next_insn = word;
1442
1443 insn = (union mips_instruction)(mminsn.insn);
1444 if (mm_isBranchInstr(regs, mminsn, &contpc))
1445 insn = (union mips_instruction)(mminsn.next_insn);
1446
1447 /* Parse instruction to find what to do */
1448
1449 switch (insn.mm_i_format.opcode) {
1450
1451 case mm_pool32a_op:
1452 switch (insn.mm_x_format.func) {
1453 case mm_lwxs_op:
1454 reg = insn.mm_x_format.rd;
1455 goto loadW;
1456 }
1457
1458 goto sigbus;
1459
1460 case mm_pool32b_op:
1461 switch (insn.mm_m_format.func) {
1462 case mm_lwp_func:
1463 reg = insn.mm_m_format.rd;
1464 if (reg == 31)
1465 goto sigbus;
1466
1467 if (!access_ok(addr, 8))
1468 goto sigbus;
1469
1470 LoadW(addr, value, res);
1471 if (res)
1472 goto fault;
1473 regs->regs[reg] = value;
1474 addr += 4;
1475 LoadW(addr, value, res);
1476 if (res)
1477 goto fault;
1478 regs->regs[reg + 1] = value;
1479 goto success;
1480
1481 case mm_swp_func:
1482 reg = insn.mm_m_format.rd;
1483 if (reg == 31)
1484 goto sigbus;
1485
1486 if (!access_ok(addr, 8))
1487 goto sigbus;
1488
1489 value = regs->regs[reg];
1490 StoreW(addr, value, res);
1491 if (res)
1492 goto fault;
1493 addr += 4;
1494 value = regs->regs[reg + 1];
1495 StoreW(addr, value, res);
1496 if (res)
1497 goto fault;
1498 goto success;
1499
1500 case mm_ldp_func:
1501 #ifdef CONFIG_64BIT
1502 reg = insn.mm_m_format.rd;
1503 if (reg == 31)
1504 goto sigbus;
1505
1506 if (!access_ok(addr, 16))
1507 goto sigbus;
1508
1509 LoadDW(addr, value, res);
1510 if (res)
1511 goto fault;
1512 regs->regs[reg] = value;
1513 addr += 8;
1514 LoadDW(addr, value, res);
1515 if (res)
1516 goto fault;
1517 regs->regs[reg + 1] = value;
1518 goto success;
1519 #endif /* CONFIG_64BIT */
1520
1521 goto sigill;
1522
1523 case mm_sdp_func:
1524 #ifdef CONFIG_64BIT
1525 reg = insn.mm_m_format.rd;
1526 if (reg == 31)
1527 goto sigbus;
1528
1529 if (!access_ok(addr, 16))
1530 goto sigbus;
1531
1532 value = regs->regs[reg];
1533 StoreDW(addr, value, res);
1534 if (res)
1535 goto fault;
1536 addr += 8;
1537 value = regs->regs[reg + 1];
1538 StoreDW(addr, value, res);
1539 if (res)
1540 goto fault;
1541 goto success;
1542 #endif /* CONFIG_64BIT */
1543
1544 goto sigill;
1545
1546 case mm_lwm32_func:
1547 reg = insn.mm_m_format.rd;
1548 rvar = reg & 0xf;
1549 if ((rvar > 9) || !reg)
1550 goto sigill;
1551 if (reg & 0x10) {
1552 if (!access_ok(addr, 4 * (rvar + 1)))
1553 goto sigbus;
1554 } else {
1555 if (!access_ok(addr, 4 * rvar))
1556 goto sigbus;
1557 }
1558 if (rvar == 9)
1559 rvar = 8;
1560 for (i = 16; rvar; rvar--, i++) {
1561 LoadW(addr, value, res);
1562 if (res)
1563 goto fault;
1564 addr += 4;
1565 regs->regs[i] = value;
1566 }
1567 if ((reg & 0xf) == 9) {
1568 LoadW(addr, value, res);
1569 if (res)
1570 goto fault;
1571 addr += 4;
1572 regs->regs[30] = value;
1573 }
1574 if (reg & 0x10) {
1575 LoadW(addr, value, res);
1576 if (res)
1577 goto fault;
1578 regs->regs[31] = value;
1579 }
1580 goto success;
1581
1582 case mm_swm32_func:
1583 reg = insn.mm_m_format.rd;
1584 rvar = reg & 0xf;
1585 if ((rvar > 9) || !reg)
1586 goto sigill;
1587 if (reg & 0x10) {
1588 if (!access_ok(addr, 4 * (rvar + 1)))
1589 goto sigbus;
1590 } else {
1591 if (!access_ok(addr, 4 * rvar))
1592 goto sigbus;
1593 }
1594 if (rvar == 9)
1595 rvar = 8;
1596 for (i = 16; rvar; rvar--, i++) {
1597 value = regs->regs[i];
1598 StoreW(addr, value, res);
1599 if (res)
1600 goto fault;
1601 addr += 4;
1602 }
1603 if ((reg & 0xf) == 9) {
1604 value = regs->regs[30];
1605 StoreW(addr, value, res);
1606 if (res)
1607 goto fault;
1608 addr += 4;
1609 }
1610 if (reg & 0x10) {
1611 value = regs->regs[31];
1612 StoreW(addr, value, res);
1613 if (res)
1614 goto fault;
1615 }
1616 goto success;
1617
1618 case mm_ldm_func:
1619 #ifdef CONFIG_64BIT
1620 reg = insn.mm_m_format.rd;
1621 rvar = reg & 0xf;
1622 if ((rvar > 9) || !reg)
1623 goto sigill;
1624 if (reg & 0x10) {
1625 if (!access_ok(addr, 8 * (rvar + 1)))
1626 goto sigbus;
1627 } else {
1628 if (!access_ok(addr, 8 * rvar))
1629 goto sigbus;
1630 }
1631 if (rvar == 9)
1632 rvar = 8;
1633
1634 for (i = 16; rvar; rvar--, i++) {
1635 LoadDW(addr, value, res);
1636 if (res)
1637 goto fault;
1638 addr += 4;
1639 regs->regs[i] = value;
1640 }
1641 if ((reg & 0xf) == 9) {
1642 LoadDW(addr, value, res);
1643 if (res)
1644 goto fault;
1645 addr += 8;
1646 regs->regs[30] = value;
1647 }
1648 if (reg & 0x10) {
1649 LoadDW(addr, value, res);
1650 if (res)
1651 goto fault;
1652 regs->regs[31] = value;
1653 }
1654 goto success;
1655 #endif /* CONFIG_64BIT */
1656
1657 goto sigill;
1658
1659 case mm_sdm_func:
1660 #ifdef CONFIG_64BIT
1661 reg = insn.mm_m_format.rd;
1662 rvar = reg & 0xf;
1663 if ((rvar > 9) || !reg)
1664 goto sigill;
1665 if (reg & 0x10) {
1666 if (!access_ok(addr, 8 * (rvar + 1)))
1667 goto sigbus;
1668 } else {
1669 if (!access_ok(addr, 8 * rvar))
1670 goto sigbus;
1671 }
1672 if (rvar == 9)
1673 rvar = 8;
1674
1675 for (i = 16; rvar; rvar--, i++) {
1676 value = regs->regs[i];
1677 StoreDW(addr, value, res);
1678 if (res)
1679 goto fault;
1680 addr += 8;
1681 }
1682 if ((reg & 0xf) == 9) {
1683 value = regs->regs[30];
1684 StoreDW(addr, value, res);
1685 if (res)
1686 goto fault;
1687 addr += 8;
1688 }
1689 if (reg & 0x10) {
1690 value = regs->regs[31];
1691 StoreDW(addr, value, res);
1692 if (res)
1693 goto fault;
1694 }
1695 goto success;
1696 #endif /* CONFIG_64BIT */
1697
1698 goto sigill;
1699
1700 /* LWC2, SWC2, LDC2, SDC2 are not serviced */
1701 }
1702
1703 goto sigbus;
1704
1705 case mm_pool32c_op:
1706 switch (insn.mm_m_format.func) {
1707 case mm_lwu_func:
1708 reg = insn.mm_m_format.rd;
1709 goto loadWU;
1710 }
1711
1712 /* LL,SC,LLD,SCD are not serviced */
1713 goto sigbus;
1714
1715 #ifdef CONFIG_MIPS_FP_SUPPORT
1716 case mm_pool32f_op:
1717 switch (insn.mm_x_format.func) {
1718 case mm_lwxc1_func:
1719 case mm_swxc1_func:
1720 case mm_ldxc1_func:
1721 case mm_sdxc1_func:
1722 goto fpu_emul;
1723 }
1724
1725 goto sigbus;
1726
1727 case mm_ldc132_op:
1728 case mm_sdc132_op:
1729 case mm_lwc132_op:
1730 case mm_swc132_op: {
1731 void __user *fault_addr = NULL;
1732
1733 fpu_emul:
1734 /* roll back jump/branch */
1735 regs->cp0_epc = origpc;
1736 regs->regs[31] = orig31;
1737
1738 die_if_kernel("Unaligned FP access in kernel code", regs);
1739 BUG_ON(!used_math());
1740 BUG_ON(!is_fpu_owner());
1741
1742 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
1743 &fault_addr);
1744 own_fpu(1); /* restore FPU state */
1745
1746 /* If something went wrong, signal */
1747 process_fpemu_return(res, fault_addr, 0);
1748
1749 if (res == 0)
1750 goto success;
1751 return;
1752 }
1753 #endif /* CONFIG_MIPS_FP_SUPPORT */
1754
1755 case mm_lh32_op:
1756 reg = insn.mm_i_format.rt;
1757 goto loadHW;
1758
1759 case mm_lhu32_op:
1760 reg = insn.mm_i_format.rt;
1761 goto loadHWU;
1762
1763 case mm_lw32_op:
1764 reg = insn.mm_i_format.rt;
1765 goto loadW;
1766
1767 case mm_sh32_op:
1768 reg = insn.mm_i_format.rt;
1769 goto storeHW;
1770
1771 case mm_sw32_op:
1772 reg = insn.mm_i_format.rt;
1773 goto storeW;
1774
1775 case mm_ld32_op:
1776 reg = insn.mm_i_format.rt;
1777 goto loadDW;
1778
1779 case mm_sd32_op:
1780 reg = insn.mm_i_format.rt;
1781 goto storeDW;
1782
1783 case mm_pool16c_op:
1784 switch (insn.mm16_m_format.func) {
1785 case mm_lwm16_op:
1786 reg = insn.mm16_m_format.rlist;
1787 rvar = reg + 1;
1788 if (!access_ok(addr, 4 * rvar))
1789 goto sigbus;
1790
1791 for (i = 16; rvar; rvar--, i++) {
1792 LoadW(addr, value, res);
1793 if (res)
1794 goto fault;
1795 addr += 4;
1796 regs->regs[i] = value;
1797 }
1798 LoadW(addr, value, res);
1799 if (res)
1800 goto fault;
1801 regs->regs[31] = value;
1802
1803 goto success;
1804
1805 case mm_swm16_op:
1806 reg = insn.mm16_m_format.rlist;
1807 rvar = reg + 1;
1808 if (!access_ok(addr, 4 * rvar))
1809 goto sigbus;
1810
1811 for (i = 16; rvar; rvar--, i++) {
1812 value = regs->regs[i];
1813 StoreW(addr, value, res);
1814 if (res)
1815 goto fault;
1816 addr += 4;
1817 }
1818 value = regs->regs[31];
1819 StoreW(addr, value, res);
1820 if (res)
1821 goto fault;
1822
1823 goto success;
1824
1825 }
1826
1827 goto sigbus;
1828
1829 case mm_lhu16_op:
1830 reg = reg16to32[insn.mm16_rb_format.rt];
1831 goto loadHWU;
1832
1833 case mm_lw16_op:
1834 reg = reg16to32[insn.mm16_rb_format.rt];
1835 goto loadW;
1836
1837 case mm_sh16_op:
1838 reg = reg16to32st[insn.mm16_rb_format.rt];
1839 goto storeHW;
1840
1841 case mm_sw16_op:
1842 reg = reg16to32st[insn.mm16_rb_format.rt];
1843 goto storeW;
1844
1845 case mm_lwsp16_op:
1846 reg = insn.mm16_r5_format.rt;
1847 goto loadW;
1848
1849 case mm_swsp16_op:
1850 reg = insn.mm16_r5_format.rt;
1851 goto storeW;
1852
1853 case mm_lwgp16_op:
1854 reg = reg16to32[insn.mm16_r3_format.rt];
1855 goto loadW;
1856
1857 default:
1858 goto sigill;
1859 }
1860
1861 loadHW:
1862 if (!access_ok(addr, 2))
1863 goto sigbus;
1864
1865 LoadHW(addr, value, res);
1866 if (res)
1867 goto fault;
1868 regs->regs[reg] = value;
1869 goto success;
1870
1871 loadHWU:
1872 if (!access_ok(addr, 2))
1873 goto sigbus;
1874
1875 LoadHWU(addr, value, res);
1876 if (res)
1877 goto fault;
1878 regs->regs[reg] = value;
1879 goto success;
1880
1881 loadW:
1882 if (!access_ok(addr, 4))
1883 goto sigbus;
1884
1885 LoadW(addr, value, res);
1886 if (res)
1887 goto fault;
1888 regs->regs[reg] = value;
1889 goto success;
1890
1891 loadWU:
1892 #ifdef CONFIG_64BIT
1893 /*
1894 * A 32-bit kernel might be running on a 64-bit processor. But
1895 * if we're on a 32-bit processor and an i-cache incoherency
1896 * or race makes us see a 64-bit instruction here the sdl/sdr
1897 * would blow up, so for now we don't handle unaligned 64-bit
1898 * instructions on 32-bit kernels.
1899 */
1900 if (!access_ok(addr, 4))
1901 goto sigbus;
1902
1903 LoadWU(addr, value, res);
1904 if (res)
1905 goto fault;
1906 regs->regs[reg] = value;
1907 goto success;
1908 #endif /* CONFIG_64BIT */
1909
1910 /* Cannot handle 64-bit instructions in 32-bit kernel */
1911 goto sigill;
1912
1913 loadDW:
1914 #ifdef CONFIG_64BIT
1915 /*
1916 * A 32-bit kernel might be running on a 64-bit processor. But
1917 * if we're on a 32-bit processor and an i-cache incoherency
1918 * or race makes us see a 64-bit instruction here the sdl/sdr
1919 * would blow up, so for now we don't handle unaligned 64-bit
1920 * instructions on 32-bit kernels.
1921 */
1922 if (!access_ok(addr, 8))
1923 goto sigbus;
1924
1925 LoadDW(addr, value, res);
1926 if (res)
1927 goto fault;
1928 regs->regs[reg] = value;
1929 goto success;
1930 #endif /* CONFIG_64BIT */
1931
1932 /* Cannot handle 64-bit instructions in 32-bit kernel */
1933 goto sigill;
1934
1935 storeHW:
1936 if (!access_ok(addr, 2))
1937 goto sigbus;
1938
1939 value = regs->regs[reg];
1940 StoreHW(addr, value, res);
1941 if (res)
1942 goto fault;
1943 goto success;
1944
1945 storeW:
1946 if (!access_ok(addr, 4))
1947 goto sigbus;
1948
1949 value = regs->regs[reg];
1950 StoreW(addr, value, res);
1951 if (res)
1952 goto fault;
1953 goto success;
1954
1955 storeDW:
1956 #ifdef CONFIG_64BIT
1957 /*
1958 * A 32-bit kernel might be running on a 64-bit processor. But
1959 * if we're on a 32-bit processor and an i-cache incoherency
1960 * or race makes us see a 64-bit instruction here the sdl/sdr
1961 * would blow up, so for now we don't handle unaligned 64-bit
1962 * instructions on 32-bit kernels.
1963 */
1964 if (!access_ok(addr, 8))
1965 goto sigbus;
1966
1967 value = regs->regs[reg];
1968 StoreDW(addr, value, res);
1969 if (res)
1970 goto fault;
1971 goto success;
1972 #endif /* CONFIG_64BIT */
1973
1974 /* Cannot handle 64-bit instructions in 32-bit kernel */
1975 goto sigill;
1976
1977 success:
1978 regs->cp0_epc = contpc; /* advance or branch */
1979
1980 #ifdef CONFIG_DEBUG_FS
1981 unaligned_instructions++;
1982 #endif
1983 return;
1984
1985 fault:
1986 /* roll back jump/branch */
1987 regs->cp0_epc = origpc;
1988 regs->regs[31] = orig31;
1989 /* Did we have an exception handler installed? */
1990 if (fixup_exception(regs))
1991 return;
1992
1993 die_if_kernel("Unhandled kernel unaligned access", regs);
1994 force_sig(SIGSEGV);
1995
1996 return;
1997
1998 sigbus:
1999 die_if_kernel("Unhandled kernel unaligned access", regs);
2000 force_sig(SIGBUS);
2001
2002 return;
2003
2004 sigill:
2005 die_if_kernel
2006 ("Unhandled kernel unaligned access or invalid instruction", regs);
2007 force_sig(SIGILL);
2008 }
2009
2010 static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
2011 {
2012 unsigned long value;
2013 unsigned int res;
2014 int reg;
2015 unsigned long orig31;
2016 u16 __user *pc16;
2017 unsigned long origpc;
2018 union mips16e_instruction mips16inst, oldinst;
2019 unsigned int opcode;
2020 int extended = 0;
2021
2022 origpc = regs->cp0_epc;
2023 orig31 = regs->regs[31];
2024 pc16 = (unsigned short __user *)msk_isa16_mode(origpc);
2025 /*
2026 * This load never faults.
2027 */
2028 __get_user(mips16inst.full, pc16);
2029 oldinst = mips16inst;
2030
2031 /* skip EXTEND instruction */
2032 if (mips16inst.ri.opcode == MIPS16e_extend_op) {
2033 extended = 1;
2034 pc16++;
2035 __get_user(mips16inst.full, pc16);
2036 } else if (delay_slot(regs)) {
2037 /* skip jump instructions */
2038 /* JAL/JALX are 32 bits but have OPCODE in first short int */
2039 if (mips16inst.ri.opcode == MIPS16e_jal_op)
2040 pc16++;
2041 pc16++;
2042 if (get_user(mips16inst.full, pc16))
2043 goto sigbus;
2044 }
2045
2046 opcode = mips16inst.ri.opcode;
2047 switch (opcode) {
2048 case MIPS16e_i64_op: /* I64 or RI64 instruction */
2049 switch (mips16inst.i64.func) { /* I64/RI64 func field check */
2050 case MIPS16e_ldpc_func:
2051 case MIPS16e_ldsp_func:
2052 reg = reg16to32[mips16inst.ri64.ry];
2053 goto loadDW;
2054
2055 case MIPS16e_sdsp_func:
2056 reg = reg16to32[mips16inst.ri64.ry];
2057 goto writeDW;
2058
2059 case MIPS16e_sdrasp_func:
2060 reg = 29; /* GPRSP */
2061 goto writeDW;
2062 }
2063
2064 goto sigbus;
2065
2066 case MIPS16e_swsp_op:
2067 reg = reg16to32[mips16inst.ri.rx];
2068 if (extended && cpu_has_mips16e2)
2069 switch (mips16inst.ri.imm >> 5) {
2070 case 0: /* SWSP */
2071 case 1: /* SWGP */
2072 break;
2073 case 2: /* SHGP */
2074 opcode = MIPS16e_sh_op;
2075 break;
2076 default:
2077 goto sigbus;
2078 }
2079 break;
2080
2081 case MIPS16e_lwpc_op:
2082 reg = reg16to32[mips16inst.ri.rx];
2083 break;
2084
2085 case MIPS16e_lwsp_op:
2086 reg = reg16to32[mips16inst.ri.rx];
2087 if (extended && cpu_has_mips16e2)
2088 switch (mips16inst.ri.imm >> 5) {
2089 case 0: /* LWSP */
2090 case 1: /* LWGP */
2091 break;
2092 case 2: /* LHGP */
2093 opcode = MIPS16e_lh_op;
2094 break;
2095 case 4: /* LHUGP */
2096 opcode = MIPS16e_lhu_op;
2097 break;
2098 default:
2099 goto sigbus;
2100 }
2101 break;
2102
2103 case MIPS16e_i8_op:
2104 if (mips16inst.i8.func != MIPS16e_swrasp_func)
2105 goto sigbus;
2106 reg = 29; /* GPRSP */
2107 break;
2108
2109 default:
2110 reg = reg16to32[mips16inst.rri.ry];
2111 break;
2112 }
2113
2114 switch (opcode) {
2115
2116 case MIPS16e_lb_op:
2117 case MIPS16e_lbu_op:
2118 case MIPS16e_sb_op:
2119 goto sigbus;
2120
2121 case MIPS16e_lh_op:
2122 if (!access_ok(addr, 2))
2123 goto sigbus;
2124
2125 LoadHW(addr, value, res);
2126 if (res)
2127 goto fault;
2128 MIPS16e_compute_return_epc(regs, &oldinst);
2129 regs->regs[reg] = value;
2130 break;
2131
2132 case MIPS16e_lhu_op:
2133 if (!access_ok(addr, 2))
2134 goto sigbus;
2135
2136 LoadHWU(addr, value, res);
2137 if (res)
2138 goto fault;
2139 MIPS16e_compute_return_epc(regs, &oldinst);
2140 regs->regs[reg] = value;
2141 break;
2142
2143 case MIPS16e_lw_op:
2144 case MIPS16e_lwpc_op:
2145 case MIPS16e_lwsp_op:
2146 if (!access_ok(addr, 4))
2147 goto sigbus;
2148
2149 LoadW(addr, value, res);
2150 if (res)
2151 goto fault;
2152 MIPS16e_compute_return_epc(regs, &oldinst);
2153 regs->regs[reg] = value;
2154 break;
2155
2156 case MIPS16e_lwu_op:
2157 #ifdef CONFIG_64BIT
2158 /*
2159 * A 32-bit kernel might be running on a 64-bit processor. But
2160 * if we're on a 32-bit processor and an i-cache incoherency
2161 * or race makes us see a 64-bit instruction here the sdl/sdr
2162 * would blow up, so for now we don't handle unaligned 64-bit
2163 * instructions on 32-bit kernels.
2164 */
2165 if (!access_ok(addr, 4))
2166 goto sigbus;
2167
2168 LoadWU(addr, value, res);
2169 if (res)
2170 goto fault;
2171 MIPS16e_compute_return_epc(regs, &oldinst);
2172 regs->regs[reg] = value;
2173 break;
2174 #endif /* CONFIG_64BIT */
2175
2176 /* Cannot handle 64-bit instructions in 32-bit kernel */
2177 goto sigill;
2178
2179 case MIPS16e_ld_op:
2180 loadDW:
2181 #ifdef CONFIG_64BIT
2182 /*
2183 * A 32-bit kernel might be running on a 64-bit processor. But
2184 * if we're on a 32-bit processor and an i-cache incoherency
2185 * or race makes us see a 64-bit instruction here the sdl/sdr
2186 * would blow up, so for now we don't handle unaligned 64-bit
2187 * instructions on 32-bit kernels.
2188 */
2189 if (!access_ok(addr, 8))
2190 goto sigbus;
2191
2192 LoadDW(addr, value, res);
2193 if (res)
2194 goto fault;
2195 MIPS16e_compute_return_epc(regs, &oldinst);
2196 regs->regs[reg] = value;
2197 break;
2198 #endif /* CONFIG_64BIT */
2199
2200 /* Cannot handle 64-bit instructions in 32-bit kernel */
2201 goto sigill;
2202
2203 case MIPS16e_sh_op:
2204 if (!access_ok(addr, 2))
2205 goto sigbus;
2206
2207 MIPS16e_compute_return_epc(regs, &oldinst);
2208 value = regs->regs[reg];
2209 StoreHW(addr, value, res);
2210 if (res)
2211 goto fault;
2212 break;
2213
2214 case MIPS16e_sw_op:
2215 case MIPS16e_swsp_op:
2216 case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */
2217 if (!access_ok(addr, 4))
2218 goto sigbus;
2219
2220 MIPS16e_compute_return_epc(regs, &oldinst);
2221 value = regs->regs[reg];
2222 StoreW(addr, value, res);
2223 if (res)
2224 goto fault;
2225 break;
2226
2227 case MIPS16e_sd_op:
2228 writeDW:
2229 #ifdef CONFIG_64BIT
2230 /*
2231 * A 32-bit kernel might be running on a 64-bit processor. But
2232 * if we're on a 32-bit processor and an i-cache incoherency
2233 * or race makes us see a 64-bit instruction here the sdl/sdr
2234 * would blow up, so for now we don't handle unaligned 64-bit
2235 * instructions on 32-bit kernels.
2236 */
2237 if (!access_ok(addr, 8))
2238 goto sigbus;
2239
2240 MIPS16e_compute_return_epc(regs, &oldinst);
2241 value = regs->regs[reg];
2242 StoreDW(addr, value, res);
2243 if (res)
2244 goto fault;
2245 break;
2246 #endif /* CONFIG_64BIT */
2247
2248 /* Cannot handle 64-bit instructions in 32-bit kernel */
2249 goto sigill;
2250
2251 default:
2252 /*
2253 * Pheeee... We encountered an yet unknown instruction or
2254 * cache coherence problem. Die sucker, die ...
2255 */
2256 goto sigill;
2257 }
2258
2259 #ifdef CONFIG_DEBUG_FS
2260 unaligned_instructions++;
2261 #endif
2262
2263 return;
2264
2265 fault:
2266 /* roll back jump/branch */
2267 regs->cp0_epc = origpc;
2268 regs->regs[31] = orig31;
2269 /* Did we have an exception handler installed? */
2270 if (fixup_exception(regs))
2271 return;
2272
2273 die_if_kernel("Unhandled kernel unaligned access", regs);
2274 force_sig(SIGSEGV);
2275
2276 return;
2277
2278 sigbus:
2279 die_if_kernel("Unhandled kernel unaligned access", regs);
2280 force_sig(SIGBUS);
2281
2282 return;
2283
2284 sigill:
2285 die_if_kernel
2286 ("Unhandled kernel unaligned access or invalid instruction", regs);
2287 force_sig(SIGILL);
2288 }
2289
2290 asmlinkage void do_ade(struct pt_regs *regs)
2291 {
2292 enum ctx_state prev_state;
2293 unsigned int __user *pc;
2294 mm_segment_t seg;
2295
2296 prev_state = exception_enter();
2297 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS,
2298 1, regs, regs->cp0_badvaddr);
2299 /*
2300 * Did we catch a fault trying to load an instruction?
2301 */
2302 if (regs->cp0_badvaddr == regs->cp0_epc)
2303 goto sigbus;
2304
2305 if (user_mode(regs) && !test_thread_flag(TIF_FIXADE))
2306 goto sigbus;
2307 if (unaligned_action == UNALIGNED_ACTION_SIGNAL)
2308 goto sigbus;
2309
2310 /*
2311 * Do branch emulation only if we didn't forward the exception.
2312 * This is all so but ugly ...
2313 */
2314
2315 /*
2316 * Are we running in microMIPS mode?
2317 */
2318 if (get_isa16_mode(regs->cp0_epc)) {
2319 /*
2320 * Did we catch a fault trying to load an instruction in
2321 * 16-bit mode?
2322 */
2323 if (regs->cp0_badvaddr == msk_isa16_mode(regs->cp0_epc))
2324 goto sigbus;
2325 if (unaligned_action == UNALIGNED_ACTION_SHOW)
2326 show_registers(regs);
2327
2328 if (cpu_has_mmips) {
2329 seg = get_fs();
2330 if (!user_mode(regs))
2331 set_fs(KERNEL_DS);
2332 emulate_load_store_microMIPS(regs,
2333 (void __user *)regs->cp0_badvaddr);
2334 set_fs(seg);
2335
2336 return;
2337 }
2338
2339 if (cpu_has_mips16) {
2340 seg = get_fs();
2341 if (!user_mode(regs))
2342 set_fs(KERNEL_DS);
2343 emulate_load_store_MIPS16e(regs,
2344 (void __user *)regs->cp0_badvaddr);
2345 set_fs(seg);
2346
2347 return;
2348 }
2349
2350 goto sigbus;
2351 }
2352
2353 if (unaligned_action == UNALIGNED_ACTION_SHOW)
2354 show_registers(regs);
2355 pc = (unsigned int __user *)exception_epc(regs);
2356
2357 seg = get_fs();
2358 if (!user_mode(regs))
2359 set_fs(KERNEL_DS);
2360 emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc);
2361 set_fs(seg);
2362
2363 return;
2364
2365 sigbus:
2366 die_if_kernel("Kernel unaligned instruction access", regs);
2367 force_sig(SIGBUS);
2368
2369 /*
2370 * XXX On return from the signal handler we should advance the epc
2371 */
2372 exception_exit(prev_state);
2373 }
2374
2375 #ifdef CONFIG_DEBUG_FS
2376 static int __init debugfs_unaligned(void)
2377 {
2378 debugfs_create_u32("unaligned_instructions", S_IRUGO, mips_debugfs_dir,
2379 &unaligned_instructions);
2380 debugfs_create_u32("unaligned_action", S_IRUGO | S_IWUSR,
2381 mips_debugfs_dir, &unaligned_action);
2382 return 0;
2383 }
2384 arch_initcall(debugfs_unaligned);
2385 #endif