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
emulate_load_store_insn(struct pt_regs * regs,void __user * addr,unsigned int __user * pc)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 case spec3_op:
943 if (insn.dsp_format.func == lx_op) {
944 switch (insn.dsp_format.op) {
945 case lwx_op:
946 if (!access_ok(VERIFY_READ, addr, 4))
947 goto sigbus;
948 LoadW(addr, value, res);
949 if (res)
950 goto fault;
951 compute_return_epc(regs);
952 regs->regs[insn.dsp_format.rd] = value;
953 break;
954 case lhx_op:
955 if (!access_ok(VERIFY_READ, addr, 2))
956 goto sigbus;
957 LoadHW(addr, value, res);
958 if (res)
959 goto fault;
960 compute_return_epc(regs);
961 regs->regs[insn.dsp_format.rd] = value;
962 break;
963 default:
964 goto sigill;
965 }
966 }
967 #ifdef CONFIG_EVA
968 else {
969 /*
970 * we can land here only from kernel accessing user
971 * memory, so we need to "switch" the address limit to
972 * user space, so that address check can work properly.
973 */
974 seg = get_fs();
975 set_fs(USER_DS);
976 switch (insn.spec3_format.func) {
977 case lhe_op:
978 if (!access_ok(VERIFY_READ, addr, 2)) {
979 set_fs(seg);
980 goto sigbus;
981 }
982 LoadHWE(addr, value, res);
983 if (res) {
984 set_fs(seg);
985 goto fault;
986 }
987 compute_return_epc(regs);
988 regs->regs[insn.spec3_format.rt] = value;
989 break;
990 case lwe_op:
991 if (!access_ok(VERIFY_READ, addr, 4)) {
992 set_fs(seg);
993 goto sigbus;
994 }
995 LoadWE(addr, value, res);
996 if (res) {
997 set_fs(seg);
998 goto fault;
999 }
1000 compute_return_epc(regs);
1001 regs->regs[insn.spec3_format.rt] = value;
1002 break;
1003 case lhue_op:
1004 if (!access_ok(VERIFY_READ, addr, 2)) {
1005 set_fs(seg);
1006 goto sigbus;
1007 }
1008 LoadHWUE(addr, value, res);
1009 if (res) {
1010 set_fs(seg);
1011 goto fault;
1012 }
1013 compute_return_epc(regs);
1014 regs->regs[insn.spec3_format.rt] = value;
1015 break;
1016 case she_op:
1017 if (!access_ok(VERIFY_WRITE, addr, 2)) {
1018 set_fs(seg);
1019 goto sigbus;
1020 }
1021 compute_return_epc(regs);
1022 value = regs->regs[insn.spec3_format.rt];
1023 StoreHWE(addr, value, res);
1024 if (res) {
1025 set_fs(seg);
1026 goto fault;
1027 }
1028 break;
1029 case swe_op:
1030 if (!access_ok(VERIFY_WRITE, addr, 4)) {
1031 set_fs(seg);
1032 goto sigbus;
1033 }
1034 compute_return_epc(regs);
1035 value = regs->regs[insn.spec3_format.rt];
1036 StoreWE(addr, value, res);
1037 if (res) {
1038 set_fs(seg);
1039 goto fault;
1040 }
1041 break;
1042 default:
1043 set_fs(seg);
1044 goto sigill;
1045 }
1046 set_fs(seg);
1047 }
1048 #endif
1049 break;
1050 case lh_op:
1051 if (!access_ok(VERIFY_READ, addr, 2))
1052 goto sigbus;
1053
1054 if (config_enabled(CONFIG_EVA)) {
1055 if (segment_eq(get_fs(), get_ds()))
1056 LoadHW(addr, value, res);
1057 else
1058 LoadHWE(addr, value, res);
1059 } else {
1060 LoadHW(addr, value, res);
1061 }
1062
1063 if (res)
1064 goto fault;
1065 compute_return_epc(regs);
1066 regs->regs[insn.i_format.rt] = value;
1067 break;
1068
1069 case lw_op:
1070 if (!access_ok(VERIFY_READ, addr, 4))
1071 goto sigbus;
1072
1073 if (config_enabled(CONFIG_EVA)) {
1074 if (segment_eq(get_fs(), get_ds()))
1075 LoadW(addr, value, res);
1076 else
1077 LoadWE(addr, value, res);
1078 } else {
1079 LoadW(addr, value, res);
1080 }
1081
1082 if (res)
1083 goto fault;
1084 compute_return_epc(regs);
1085 regs->regs[insn.i_format.rt] = value;
1086 break;
1087
1088 case lhu_op:
1089 if (!access_ok(VERIFY_READ, addr, 2))
1090 goto sigbus;
1091
1092 if (config_enabled(CONFIG_EVA)) {
1093 if (segment_eq(get_fs(), get_ds()))
1094 LoadHWU(addr, value, res);
1095 else
1096 LoadHWUE(addr, value, res);
1097 } else {
1098 LoadHWU(addr, value, res);
1099 }
1100
1101 if (res)
1102 goto fault;
1103 compute_return_epc(regs);
1104 regs->regs[insn.i_format.rt] = value;
1105 break;
1106
1107 case lwu_op:
1108 #ifdef CONFIG_64BIT
1109 /*
1110 * A 32-bit kernel might be running on a 64-bit processor. But
1111 * if we're on a 32-bit processor and an i-cache incoherency
1112 * or race makes us see a 64-bit instruction here the sdl/sdr
1113 * would blow up, so for now we don't handle unaligned 64-bit
1114 * instructions on 32-bit kernels.
1115 */
1116 if (!access_ok(VERIFY_READ, addr, 4))
1117 goto sigbus;
1118
1119 LoadWU(addr, value, res);
1120 if (res)
1121 goto fault;
1122 compute_return_epc(regs);
1123 regs->regs[insn.i_format.rt] = value;
1124 break;
1125 #endif /* CONFIG_64BIT */
1126
1127 /* Cannot handle 64-bit instructions in 32-bit kernel */
1128 goto sigill;
1129
1130 case ld_op:
1131 #ifdef CONFIG_64BIT
1132 /*
1133 * A 32-bit kernel might be running on a 64-bit processor. But
1134 * if we're on a 32-bit processor and an i-cache incoherency
1135 * or race makes us see a 64-bit instruction here the sdl/sdr
1136 * would blow up, so for now we don't handle unaligned 64-bit
1137 * instructions on 32-bit kernels.
1138 */
1139 if (!access_ok(VERIFY_READ, addr, 8))
1140 goto sigbus;
1141
1142 LoadDW(addr, value, res);
1143 if (res)
1144 goto fault;
1145 compute_return_epc(regs);
1146 regs->regs[insn.i_format.rt] = value;
1147 break;
1148 #endif /* CONFIG_64BIT */
1149
1150 /* Cannot handle 64-bit instructions in 32-bit kernel */
1151 goto sigill;
1152
1153 case sh_op:
1154 if (!access_ok(VERIFY_WRITE, addr, 2))
1155 goto sigbus;
1156
1157 compute_return_epc(regs);
1158 value = regs->regs[insn.i_format.rt];
1159
1160 if (config_enabled(CONFIG_EVA)) {
1161 if (segment_eq(get_fs(), get_ds()))
1162 StoreHW(addr, value, res);
1163 else
1164 StoreHWE(addr, value, res);
1165 } else {
1166 StoreHW(addr, value, res);
1167 }
1168
1169 if (res)
1170 goto fault;
1171 break;
1172
1173 case sw_op:
1174 if (!access_ok(VERIFY_WRITE, addr, 4))
1175 goto sigbus;
1176
1177 compute_return_epc(regs);
1178 value = regs->regs[insn.i_format.rt];
1179
1180 if (config_enabled(CONFIG_EVA)) {
1181 if (segment_eq(get_fs(), get_ds()))
1182 StoreW(addr, value, res);
1183 else
1184 StoreWE(addr, value, res);
1185 } else {
1186 StoreW(addr, value, res);
1187 }
1188
1189 if (res)
1190 goto fault;
1191 break;
1192
1193 case sd_op:
1194 #ifdef CONFIG_64BIT
1195 /*
1196 * A 32-bit kernel might be running on a 64-bit processor. But
1197 * if we're on a 32-bit processor and an i-cache incoherency
1198 * or race makes us see a 64-bit instruction here the sdl/sdr
1199 * would blow up, so for now we don't handle unaligned 64-bit
1200 * instructions on 32-bit kernels.
1201 */
1202 if (!access_ok(VERIFY_WRITE, addr, 8))
1203 goto sigbus;
1204
1205 compute_return_epc(regs);
1206 value = regs->regs[insn.i_format.rt];
1207 StoreDW(addr, value, res);
1208 if (res)
1209 goto fault;
1210 break;
1211 #endif /* CONFIG_64BIT */
1212
1213 /* Cannot handle 64-bit instructions in 32-bit kernel */
1214 goto sigill;
1215
1216 case lwc1_op:
1217 case ldc1_op:
1218 case swc1_op:
1219 case sdc1_op:
1220 case cop1x_op:
1221 die_if_kernel("Unaligned FP access in kernel code", regs);
1222 BUG_ON(!used_math());
1223
1224 lose_fpu(1); /* Save FPU state for the emulator. */
1225 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
1226 &fault_addr);
1227 own_fpu(1); /* Restore FPU state. */
1228
1229 /* Signal if something went wrong. */
1230 process_fpemu_return(res, fault_addr, 0);
1231
1232 if (res == 0)
1233 break;
1234 return;
1235
1236 case msa_op:
1237 if (!cpu_has_msa)
1238 goto sigill;
1239
1240 /*
1241 * If we've reached this point then userland should have taken
1242 * the MSA disabled exception & initialised vector context at
1243 * some point in the past.
1244 */
1245 BUG_ON(!thread_msa_context_live());
1246
1247 df = insn.msa_mi10_format.df;
1248 wd = insn.msa_mi10_format.wd;
1249 fpr = ¤t->thread.fpu.fpr[wd];
1250
1251 switch (insn.msa_mi10_format.func) {
1252 case msa_ld_op:
1253 if (!access_ok(VERIFY_READ, addr, sizeof(*fpr)))
1254 goto sigbus;
1255
1256 do {
1257 /*
1258 * If we have live MSA context keep track of
1259 * whether we get preempted in order to avoid
1260 * the register context we load being clobbered
1261 * by the live context as it's saved during
1262 * preemption. If we don't have live context
1263 * then it can't be saved to clobber the value
1264 * we load.
1265 */
1266 preempted = test_thread_flag(TIF_USEDMSA);
1267
1268 res = __copy_from_user_inatomic(fpr, addr,
1269 sizeof(*fpr));
1270 if (res)
1271 goto fault;
1272
1273 /*
1274 * Update the hardware register if it is in use
1275 * by the task in this quantum, in order to
1276 * avoid having to save & restore the whole
1277 * vector context.
1278 */
1279 preempt_disable();
1280 if (test_thread_flag(TIF_USEDMSA)) {
1281 write_msa_wr(wd, fpr, df);
1282 preempted = 0;
1283 }
1284 preempt_enable();
1285 } while (preempted);
1286 break;
1287
1288 case msa_st_op:
1289 if (!access_ok(VERIFY_WRITE, addr, sizeof(*fpr)))
1290 goto sigbus;
1291
1292 /*
1293 * Update from the hardware register if it is in use by
1294 * the task in this quantum, in order to avoid having to
1295 * save & restore the whole vector context.
1296 */
1297 preempt_disable();
1298 if (test_thread_flag(TIF_USEDMSA))
1299 read_msa_wr(wd, fpr, df);
1300 preempt_enable();
1301
1302 res = __copy_to_user_inatomic(addr, fpr, sizeof(*fpr));
1303 if (res)
1304 goto fault;
1305 break;
1306
1307 default:
1308 goto sigbus;
1309 }
1310
1311 compute_return_epc(regs);
1312 break;
1313
1314 #ifndef CONFIG_CPU_MIPSR6
1315 /*
1316 * COP2 is available to implementor for application specific use.
1317 * It's up to applications to register a notifier chain and do
1318 * whatever they have to do, including possible sending of signals.
1319 *
1320 * This instruction has been reallocated in Release 6
1321 */
1322 case lwc2_op:
1323 cu2_notifier_call_chain(CU2_LWC2_OP, regs);
1324 break;
1325
1326 case ldc2_op:
1327 cu2_notifier_call_chain(CU2_LDC2_OP, regs);
1328 break;
1329
1330 case swc2_op:
1331 cu2_notifier_call_chain(CU2_SWC2_OP, regs);
1332 break;
1333
1334 case sdc2_op:
1335 cu2_notifier_call_chain(CU2_SDC2_OP, regs);
1336 break;
1337 #endif
1338 default:
1339 /*
1340 * Pheeee... We encountered an yet unknown instruction or
1341 * cache coherence problem. Die sucker, die ...
1342 */
1343 goto sigill;
1344 }
1345
1346 #ifdef CONFIG_DEBUG_FS
1347 unaligned_instructions++;
1348 #endif
1349
1350 return;
1351
1352 fault:
1353 /* roll back jump/branch */
1354 regs->cp0_epc = origpc;
1355 regs->regs[31] = orig31;
1356 /* Did we have an exception handler installed? */
1357 if (fixup_exception(regs))
1358 return;
1359
1360 die_if_kernel("Unhandled kernel unaligned access", regs);
1361 force_sig(SIGSEGV, current);
1362
1363 return;
1364
1365 sigbus:
1366 die_if_kernel("Unhandled kernel unaligned access", regs);
1367 force_sig(SIGBUS, current);
1368
1369 return;
1370
1371 sigill:
1372 die_if_kernel
1373 ("Unhandled kernel unaligned access or invalid instruction", regs);
1374 force_sig(SIGILL, current);
1375 }
1376
1377 /* Recode table from 16-bit register notation to 32-bit GPR. */
1378 const int reg16to32[] = { 16, 17, 2, 3, 4, 5, 6, 7 };
1379
1380 /* Recode table from 16-bit STORE register notation to 32-bit GPR. */
1381 const int reg16to32st[] = { 0, 17, 2, 3, 4, 5, 6, 7 };
1382
emulate_load_store_microMIPS(struct pt_regs * regs,void __user * addr)1383 static void emulate_load_store_microMIPS(struct pt_regs *regs,
1384 void __user *addr)
1385 {
1386 unsigned long value;
1387 unsigned int res;
1388 int i;
1389 unsigned int reg = 0, rvar;
1390 unsigned long orig31;
1391 u16 __user *pc16;
1392 u16 halfword;
1393 unsigned int word;
1394 unsigned long origpc, contpc;
1395 union mips_instruction insn;
1396 struct mm_decoded_insn mminsn;
1397 void __user *fault_addr = NULL;
1398
1399 origpc = regs->cp0_epc;
1400 orig31 = regs->regs[31];
1401
1402 mminsn.micro_mips_mode = 1;
1403
1404 /*
1405 * This load never faults.
1406 */
1407 pc16 = (unsigned short __user *)msk_isa16_mode(regs->cp0_epc);
1408 __get_user(halfword, pc16);
1409 pc16++;
1410 contpc = regs->cp0_epc + 2;
1411 word = ((unsigned int)halfword << 16);
1412 mminsn.pc_inc = 2;
1413
1414 if (!mm_insn_16bit(halfword)) {
1415 __get_user(halfword, pc16);
1416 pc16++;
1417 contpc = regs->cp0_epc + 4;
1418 mminsn.pc_inc = 4;
1419 word |= halfword;
1420 }
1421 mminsn.insn = word;
1422
1423 if (get_user(halfword, pc16))
1424 goto fault;
1425 mminsn.next_pc_inc = 2;
1426 word = ((unsigned int)halfword << 16);
1427
1428 if (!mm_insn_16bit(halfword)) {
1429 pc16++;
1430 if (get_user(halfword, pc16))
1431 goto fault;
1432 mminsn.next_pc_inc = 4;
1433 word |= halfword;
1434 }
1435 mminsn.next_insn = word;
1436
1437 insn = (union mips_instruction)(mminsn.insn);
1438 if (mm_isBranchInstr(regs, mminsn, &contpc))
1439 insn = (union mips_instruction)(mminsn.next_insn);
1440
1441 /* Parse instruction to find what to do */
1442
1443 switch (insn.mm_i_format.opcode) {
1444
1445 case mm_pool32a_op:
1446 switch (insn.mm_x_format.func) {
1447 case mm_lwxs_op:
1448 reg = insn.mm_x_format.rd;
1449 goto loadW;
1450 }
1451
1452 goto sigbus;
1453
1454 case mm_pool32b_op:
1455 switch (insn.mm_m_format.func) {
1456 case mm_lwp_func:
1457 reg = insn.mm_m_format.rd;
1458 if (reg == 31)
1459 goto sigbus;
1460
1461 if (!access_ok(VERIFY_READ, addr, 8))
1462 goto sigbus;
1463
1464 LoadW(addr, value, res);
1465 if (res)
1466 goto fault;
1467 regs->regs[reg] = value;
1468 addr += 4;
1469 LoadW(addr, value, res);
1470 if (res)
1471 goto fault;
1472 regs->regs[reg + 1] = value;
1473 goto success;
1474
1475 case mm_swp_func:
1476 reg = insn.mm_m_format.rd;
1477 if (reg == 31)
1478 goto sigbus;
1479
1480 if (!access_ok(VERIFY_WRITE, addr, 8))
1481 goto sigbus;
1482
1483 value = regs->regs[reg];
1484 StoreW(addr, value, res);
1485 if (res)
1486 goto fault;
1487 addr += 4;
1488 value = regs->regs[reg + 1];
1489 StoreW(addr, value, res);
1490 if (res)
1491 goto fault;
1492 goto success;
1493
1494 case mm_ldp_func:
1495 #ifdef CONFIG_64BIT
1496 reg = insn.mm_m_format.rd;
1497 if (reg == 31)
1498 goto sigbus;
1499
1500 if (!access_ok(VERIFY_READ, addr, 16))
1501 goto sigbus;
1502
1503 LoadDW(addr, value, res);
1504 if (res)
1505 goto fault;
1506 regs->regs[reg] = value;
1507 addr += 8;
1508 LoadDW(addr, value, res);
1509 if (res)
1510 goto fault;
1511 regs->regs[reg + 1] = value;
1512 goto success;
1513 #endif /* CONFIG_64BIT */
1514
1515 goto sigill;
1516
1517 case mm_sdp_func:
1518 #ifdef CONFIG_64BIT
1519 reg = insn.mm_m_format.rd;
1520 if (reg == 31)
1521 goto sigbus;
1522
1523 if (!access_ok(VERIFY_WRITE, addr, 16))
1524 goto sigbus;
1525
1526 value = regs->regs[reg];
1527 StoreDW(addr, value, res);
1528 if (res)
1529 goto fault;
1530 addr += 8;
1531 value = regs->regs[reg + 1];
1532 StoreDW(addr, value, res);
1533 if (res)
1534 goto fault;
1535 goto success;
1536 #endif /* CONFIG_64BIT */
1537
1538 goto sigill;
1539
1540 case mm_lwm32_func:
1541 reg = insn.mm_m_format.rd;
1542 rvar = reg & 0xf;
1543 if ((rvar > 9) || !reg)
1544 goto sigill;
1545 if (reg & 0x10) {
1546 if (!access_ok
1547 (VERIFY_READ, addr, 4 * (rvar + 1)))
1548 goto sigbus;
1549 } else {
1550 if (!access_ok(VERIFY_READ, addr, 4 * rvar))
1551 goto sigbus;
1552 }
1553 if (rvar == 9)
1554 rvar = 8;
1555 for (i = 16; rvar; rvar--, i++) {
1556 LoadW(addr, value, res);
1557 if (res)
1558 goto fault;
1559 addr += 4;
1560 regs->regs[i] = value;
1561 }
1562 if ((reg & 0xf) == 9) {
1563 LoadW(addr, value, res);
1564 if (res)
1565 goto fault;
1566 addr += 4;
1567 regs->regs[30] = value;
1568 }
1569 if (reg & 0x10) {
1570 LoadW(addr, value, res);
1571 if (res)
1572 goto fault;
1573 regs->regs[31] = value;
1574 }
1575 goto success;
1576
1577 case mm_swm32_func:
1578 reg = insn.mm_m_format.rd;
1579 rvar = reg & 0xf;
1580 if ((rvar > 9) || !reg)
1581 goto sigill;
1582 if (reg & 0x10) {
1583 if (!access_ok
1584 (VERIFY_WRITE, addr, 4 * (rvar + 1)))
1585 goto sigbus;
1586 } else {
1587 if (!access_ok(VERIFY_WRITE, addr, 4 * rvar))
1588 goto sigbus;
1589 }
1590 if (rvar == 9)
1591 rvar = 8;
1592 for (i = 16; rvar; rvar--, i++) {
1593 value = regs->regs[i];
1594 StoreW(addr, value, res);
1595 if (res)
1596 goto fault;
1597 addr += 4;
1598 }
1599 if ((reg & 0xf) == 9) {
1600 value = regs->regs[30];
1601 StoreW(addr, value, res);
1602 if (res)
1603 goto fault;
1604 addr += 4;
1605 }
1606 if (reg & 0x10) {
1607 value = regs->regs[31];
1608 StoreW(addr, value, res);
1609 if (res)
1610 goto fault;
1611 }
1612 goto success;
1613
1614 case mm_ldm_func:
1615 #ifdef CONFIG_64BIT
1616 reg = insn.mm_m_format.rd;
1617 rvar = reg & 0xf;
1618 if ((rvar > 9) || !reg)
1619 goto sigill;
1620 if (reg & 0x10) {
1621 if (!access_ok
1622 (VERIFY_READ, addr, 8 * (rvar + 1)))
1623 goto sigbus;
1624 } else {
1625 if (!access_ok(VERIFY_READ, addr, 8 * rvar))
1626 goto sigbus;
1627 }
1628 if (rvar == 9)
1629 rvar = 8;
1630
1631 for (i = 16; rvar; rvar--, i++) {
1632 LoadDW(addr, value, res);
1633 if (res)
1634 goto fault;
1635 addr += 4;
1636 regs->regs[i] = value;
1637 }
1638 if ((reg & 0xf) == 9) {
1639 LoadDW(addr, value, res);
1640 if (res)
1641 goto fault;
1642 addr += 8;
1643 regs->regs[30] = value;
1644 }
1645 if (reg & 0x10) {
1646 LoadDW(addr, value, res);
1647 if (res)
1648 goto fault;
1649 regs->regs[31] = value;
1650 }
1651 goto success;
1652 #endif /* CONFIG_64BIT */
1653
1654 goto sigill;
1655
1656 case mm_sdm_func:
1657 #ifdef CONFIG_64BIT
1658 reg = insn.mm_m_format.rd;
1659 rvar = reg & 0xf;
1660 if ((rvar > 9) || !reg)
1661 goto sigill;
1662 if (reg & 0x10) {
1663 if (!access_ok
1664 (VERIFY_WRITE, addr, 8 * (rvar + 1)))
1665 goto sigbus;
1666 } else {
1667 if (!access_ok(VERIFY_WRITE, addr, 8 * rvar))
1668 goto sigbus;
1669 }
1670 if (rvar == 9)
1671 rvar = 8;
1672
1673 for (i = 16; rvar; rvar--, i++) {
1674 value = regs->regs[i];
1675 StoreDW(addr, value, res);
1676 if (res)
1677 goto fault;
1678 addr += 8;
1679 }
1680 if ((reg & 0xf) == 9) {
1681 value = regs->regs[30];
1682 StoreDW(addr, value, res);
1683 if (res)
1684 goto fault;
1685 addr += 8;
1686 }
1687 if (reg & 0x10) {
1688 value = regs->regs[31];
1689 StoreDW(addr, value, res);
1690 if (res)
1691 goto fault;
1692 }
1693 goto success;
1694 #endif /* CONFIG_64BIT */
1695
1696 goto sigill;
1697
1698 /* LWC2, SWC2, LDC2, SDC2 are not serviced */
1699 }
1700
1701 goto sigbus;
1702
1703 case mm_pool32c_op:
1704 switch (insn.mm_m_format.func) {
1705 case mm_lwu_func:
1706 reg = insn.mm_m_format.rd;
1707 goto loadWU;
1708 }
1709
1710 /* LL,SC,LLD,SCD are not serviced */
1711 goto sigbus;
1712
1713 case mm_pool32f_op:
1714 switch (insn.mm_x_format.func) {
1715 case mm_lwxc1_func:
1716 case mm_swxc1_func:
1717 case mm_ldxc1_func:
1718 case mm_sdxc1_func:
1719 goto fpu_emul;
1720 }
1721
1722 goto sigbus;
1723
1724 case mm_ldc132_op:
1725 case mm_sdc132_op:
1726 case mm_lwc132_op:
1727 case mm_swc132_op:
1728 fpu_emul:
1729 /* roll back jump/branch */
1730 regs->cp0_epc = origpc;
1731 regs->regs[31] = orig31;
1732
1733 die_if_kernel("Unaligned FP access in kernel code", regs);
1734 BUG_ON(!used_math());
1735 BUG_ON(!is_fpu_owner());
1736
1737 lose_fpu(1); /* save the FPU state for the emulator */
1738 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
1739 &fault_addr);
1740 own_fpu(1); /* restore FPU state */
1741
1742 /* If something went wrong, signal */
1743 process_fpemu_return(res, fault_addr, 0);
1744
1745 if (res == 0)
1746 goto success;
1747 return;
1748
1749 case mm_lh32_op:
1750 reg = insn.mm_i_format.rt;
1751 goto loadHW;
1752
1753 case mm_lhu32_op:
1754 reg = insn.mm_i_format.rt;
1755 goto loadHWU;
1756
1757 case mm_lw32_op:
1758 reg = insn.mm_i_format.rt;
1759 goto loadW;
1760
1761 case mm_sh32_op:
1762 reg = insn.mm_i_format.rt;
1763 goto storeHW;
1764
1765 case mm_sw32_op:
1766 reg = insn.mm_i_format.rt;
1767 goto storeW;
1768
1769 case mm_ld32_op:
1770 reg = insn.mm_i_format.rt;
1771 goto loadDW;
1772
1773 case mm_sd32_op:
1774 reg = insn.mm_i_format.rt;
1775 goto storeDW;
1776
1777 case mm_pool16c_op:
1778 switch (insn.mm16_m_format.func) {
1779 case mm_lwm16_op:
1780 reg = insn.mm16_m_format.rlist;
1781 rvar = reg + 1;
1782 if (!access_ok(VERIFY_READ, addr, 4 * rvar))
1783 goto sigbus;
1784
1785 for (i = 16; rvar; rvar--, i++) {
1786 LoadW(addr, value, res);
1787 if (res)
1788 goto fault;
1789 addr += 4;
1790 regs->regs[i] = value;
1791 }
1792 LoadW(addr, value, res);
1793 if (res)
1794 goto fault;
1795 regs->regs[31] = value;
1796
1797 goto success;
1798
1799 case mm_swm16_op:
1800 reg = insn.mm16_m_format.rlist;
1801 rvar = reg + 1;
1802 if (!access_ok(VERIFY_WRITE, addr, 4 * rvar))
1803 goto sigbus;
1804
1805 for (i = 16; rvar; rvar--, i++) {
1806 value = regs->regs[i];
1807 StoreW(addr, value, res);
1808 if (res)
1809 goto fault;
1810 addr += 4;
1811 }
1812 value = regs->regs[31];
1813 StoreW(addr, value, res);
1814 if (res)
1815 goto fault;
1816
1817 goto success;
1818
1819 }
1820
1821 goto sigbus;
1822
1823 case mm_lhu16_op:
1824 reg = reg16to32[insn.mm16_rb_format.rt];
1825 goto loadHWU;
1826
1827 case mm_lw16_op:
1828 reg = reg16to32[insn.mm16_rb_format.rt];
1829 goto loadW;
1830
1831 case mm_sh16_op:
1832 reg = reg16to32st[insn.mm16_rb_format.rt];
1833 goto storeHW;
1834
1835 case mm_sw16_op:
1836 reg = reg16to32st[insn.mm16_rb_format.rt];
1837 goto storeW;
1838
1839 case mm_lwsp16_op:
1840 reg = insn.mm16_r5_format.rt;
1841 goto loadW;
1842
1843 case mm_swsp16_op:
1844 reg = insn.mm16_r5_format.rt;
1845 goto storeW;
1846
1847 case mm_lwgp16_op:
1848 reg = reg16to32[insn.mm16_r3_format.rt];
1849 goto loadW;
1850
1851 default:
1852 goto sigill;
1853 }
1854
1855 loadHW:
1856 if (!access_ok(VERIFY_READ, addr, 2))
1857 goto sigbus;
1858
1859 LoadHW(addr, value, res);
1860 if (res)
1861 goto fault;
1862 regs->regs[reg] = value;
1863 goto success;
1864
1865 loadHWU:
1866 if (!access_ok(VERIFY_READ, addr, 2))
1867 goto sigbus;
1868
1869 LoadHWU(addr, value, res);
1870 if (res)
1871 goto fault;
1872 regs->regs[reg] = value;
1873 goto success;
1874
1875 loadW:
1876 if (!access_ok(VERIFY_READ, addr, 4))
1877 goto sigbus;
1878
1879 LoadW(addr, value, res);
1880 if (res)
1881 goto fault;
1882 regs->regs[reg] = value;
1883 goto success;
1884
1885 loadWU:
1886 #ifdef CONFIG_64BIT
1887 /*
1888 * A 32-bit kernel might be running on a 64-bit processor. But
1889 * if we're on a 32-bit processor and an i-cache incoherency
1890 * or race makes us see a 64-bit instruction here the sdl/sdr
1891 * would blow up, so for now we don't handle unaligned 64-bit
1892 * instructions on 32-bit kernels.
1893 */
1894 if (!access_ok(VERIFY_READ, addr, 4))
1895 goto sigbus;
1896
1897 LoadWU(addr, value, res);
1898 if (res)
1899 goto fault;
1900 regs->regs[reg] = value;
1901 goto success;
1902 #endif /* CONFIG_64BIT */
1903
1904 /* Cannot handle 64-bit instructions in 32-bit kernel */
1905 goto sigill;
1906
1907 loadDW:
1908 #ifdef CONFIG_64BIT
1909 /*
1910 * A 32-bit kernel might be running on a 64-bit processor. But
1911 * if we're on a 32-bit processor and an i-cache incoherency
1912 * or race makes us see a 64-bit instruction here the sdl/sdr
1913 * would blow up, so for now we don't handle unaligned 64-bit
1914 * instructions on 32-bit kernels.
1915 */
1916 if (!access_ok(VERIFY_READ, addr, 8))
1917 goto sigbus;
1918
1919 LoadDW(addr, value, res);
1920 if (res)
1921 goto fault;
1922 regs->regs[reg] = value;
1923 goto success;
1924 #endif /* CONFIG_64BIT */
1925
1926 /* Cannot handle 64-bit instructions in 32-bit kernel */
1927 goto sigill;
1928
1929 storeHW:
1930 if (!access_ok(VERIFY_WRITE, addr, 2))
1931 goto sigbus;
1932
1933 value = regs->regs[reg];
1934 StoreHW(addr, value, res);
1935 if (res)
1936 goto fault;
1937 goto success;
1938
1939 storeW:
1940 if (!access_ok(VERIFY_WRITE, addr, 4))
1941 goto sigbus;
1942
1943 value = regs->regs[reg];
1944 StoreW(addr, value, res);
1945 if (res)
1946 goto fault;
1947 goto success;
1948
1949 storeDW:
1950 #ifdef CONFIG_64BIT
1951 /*
1952 * A 32-bit kernel might be running on a 64-bit processor. But
1953 * if we're on a 32-bit processor and an i-cache incoherency
1954 * or race makes us see a 64-bit instruction here the sdl/sdr
1955 * would blow up, so for now we don't handle unaligned 64-bit
1956 * instructions on 32-bit kernels.
1957 */
1958 if (!access_ok(VERIFY_WRITE, addr, 8))
1959 goto sigbus;
1960
1961 value = regs->regs[reg];
1962 StoreDW(addr, value, res);
1963 if (res)
1964 goto fault;
1965 goto success;
1966 #endif /* CONFIG_64BIT */
1967
1968 /* Cannot handle 64-bit instructions in 32-bit kernel */
1969 goto sigill;
1970
1971 success:
1972 regs->cp0_epc = contpc; /* advance or branch */
1973
1974 #ifdef CONFIG_DEBUG_FS
1975 unaligned_instructions++;
1976 #endif
1977 return;
1978
1979 fault:
1980 /* roll back jump/branch */
1981 regs->cp0_epc = origpc;
1982 regs->regs[31] = orig31;
1983 /* Did we have an exception handler installed? */
1984 if (fixup_exception(regs))
1985 return;
1986
1987 die_if_kernel("Unhandled kernel unaligned access", regs);
1988 force_sig(SIGSEGV, current);
1989
1990 return;
1991
1992 sigbus:
1993 die_if_kernel("Unhandled kernel unaligned access", regs);
1994 force_sig(SIGBUS, current);
1995
1996 return;
1997
1998 sigill:
1999 die_if_kernel
2000 ("Unhandled kernel unaligned access or invalid instruction", regs);
2001 force_sig(SIGILL, current);
2002 }
2003
emulate_load_store_MIPS16e(struct pt_regs * regs,void __user * addr)2004 static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
2005 {
2006 unsigned long value;
2007 unsigned int res;
2008 int reg;
2009 unsigned long orig31;
2010 u16 __user *pc16;
2011 unsigned long origpc;
2012 union mips16e_instruction mips16inst, oldinst;
2013
2014 origpc = regs->cp0_epc;
2015 orig31 = regs->regs[31];
2016 pc16 = (unsigned short __user *)msk_isa16_mode(origpc);
2017 /*
2018 * This load never faults.
2019 */
2020 __get_user(mips16inst.full, pc16);
2021 oldinst = mips16inst;
2022
2023 /* skip EXTEND instruction */
2024 if (mips16inst.ri.opcode == MIPS16e_extend_op) {
2025 pc16++;
2026 __get_user(mips16inst.full, pc16);
2027 } else if (delay_slot(regs)) {
2028 /* skip jump instructions */
2029 /* JAL/JALX are 32 bits but have OPCODE in first short int */
2030 if (mips16inst.ri.opcode == MIPS16e_jal_op)
2031 pc16++;
2032 pc16++;
2033 if (get_user(mips16inst.full, pc16))
2034 goto sigbus;
2035 }
2036
2037 switch (mips16inst.ri.opcode) {
2038 case MIPS16e_i64_op: /* I64 or RI64 instruction */
2039 switch (mips16inst.i64.func) { /* I64/RI64 func field check */
2040 case MIPS16e_ldpc_func:
2041 case MIPS16e_ldsp_func:
2042 reg = reg16to32[mips16inst.ri64.ry];
2043 goto loadDW;
2044
2045 case MIPS16e_sdsp_func:
2046 reg = reg16to32[mips16inst.ri64.ry];
2047 goto writeDW;
2048
2049 case MIPS16e_sdrasp_func:
2050 reg = 29; /* GPRSP */
2051 goto writeDW;
2052 }
2053
2054 goto sigbus;
2055
2056 case MIPS16e_swsp_op:
2057 case MIPS16e_lwpc_op:
2058 case MIPS16e_lwsp_op:
2059 reg = reg16to32[mips16inst.ri.rx];
2060 break;
2061
2062 case MIPS16e_i8_op:
2063 if (mips16inst.i8.func != MIPS16e_swrasp_func)
2064 goto sigbus;
2065 reg = 29; /* GPRSP */
2066 break;
2067
2068 default:
2069 reg = reg16to32[mips16inst.rri.ry];
2070 break;
2071 }
2072
2073 switch (mips16inst.ri.opcode) {
2074
2075 case MIPS16e_lb_op:
2076 case MIPS16e_lbu_op:
2077 case MIPS16e_sb_op:
2078 goto sigbus;
2079
2080 case MIPS16e_lh_op:
2081 if (!access_ok(VERIFY_READ, addr, 2))
2082 goto sigbus;
2083
2084 LoadHW(addr, value, res);
2085 if (res)
2086 goto fault;
2087 MIPS16e_compute_return_epc(regs, &oldinst);
2088 regs->regs[reg] = value;
2089 break;
2090
2091 case MIPS16e_lhu_op:
2092 if (!access_ok(VERIFY_READ, addr, 2))
2093 goto sigbus;
2094
2095 LoadHWU(addr, value, res);
2096 if (res)
2097 goto fault;
2098 MIPS16e_compute_return_epc(regs, &oldinst);
2099 regs->regs[reg] = value;
2100 break;
2101
2102 case MIPS16e_lw_op:
2103 case MIPS16e_lwpc_op:
2104 case MIPS16e_lwsp_op:
2105 if (!access_ok(VERIFY_READ, addr, 4))
2106 goto sigbus;
2107
2108 LoadW(addr, value, res);
2109 if (res)
2110 goto fault;
2111 MIPS16e_compute_return_epc(regs, &oldinst);
2112 regs->regs[reg] = value;
2113 break;
2114
2115 case MIPS16e_lwu_op:
2116 #ifdef CONFIG_64BIT
2117 /*
2118 * A 32-bit kernel might be running on a 64-bit processor. But
2119 * if we're on a 32-bit processor and an i-cache incoherency
2120 * or race makes us see a 64-bit instruction here the sdl/sdr
2121 * would blow up, so for now we don't handle unaligned 64-bit
2122 * instructions on 32-bit kernels.
2123 */
2124 if (!access_ok(VERIFY_READ, addr, 4))
2125 goto sigbus;
2126
2127 LoadWU(addr, value, res);
2128 if (res)
2129 goto fault;
2130 MIPS16e_compute_return_epc(regs, &oldinst);
2131 regs->regs[reg] = value;
2132 break;
2133 #endif /* CONFIG_64BIT */
2134
2135 /* Cannot handle 64-bit instructions in 32-bit kernel */
2136 goto sigill;
2137
2138 case MIPS16e_ld_op:
2139 loadDW:
2140 #ifdef CONFIG_64BIT
2141 /*
2142 * A 32-bit kernel might be running on a 64-bit processor. But
2143 * if we're on a 32-bit processor and an i-cache incoherency
2144 * or race makes us see a 64-bit instruction here the sdl/sdr
2145 * would blow up, so for now we don't handle unaligned 64-bit
2146 * instructions on 32-bit kernels.
2147 */
2148 if (!access_ok(VERIFY_READ, addr, 8))
2149 goto sigbus;
2150
2151 LoadDW(addr, value, res);
2152 if (res)
2153 goto fault;
2154 MIPS16e_compute_return_epc(regs, &oldinst);
2155 regs->regs[reg] = value;
2156 break;
2157 #endif /* CONFIG_64BIT */
2158
2159 /* Cannot handle 64-bit instructions in 32-bit kernel */
2160 goto sigill;
2161
2162 case MIPS16e_sh_op:
2163 if (!access_ok(VERIFY_WRITE, addr, 2))
2164 goto sigbus;
2165
2166 MIPS16e_compute_return_epc(regs, &oldinst);
2167 value = regs->regs[reg];
2168 StoreHW(addr, value, res);
2169 if (res)
2170 goto fault;
2171 break;
2172
2173 case MIPS16e_sw_op:
2174 case MIPS16e_swsp_op:
2175 case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */
2176 if (!access_ok(VERIFY_WRITE, addr, 4))
2177 goto sigbus;
2178
2179 MIPS16e_compute_return_epc(regs, &oldinst);
2180 value = regs->regs[reg];
2181 StoreW(addr, value, res);
2182 if (res)
2183 goto fault;
2184 break;
2185
2186 case MIPS16e_sd_op:
2187 writeDW:
2188 #ifdef CONFIG_64BIT
2189 /*
2190 * A 32-bit kernel might be running on a 64-bit processor. But
2191 * if we're on a 32-bit processor and an i-cache incoherency
2192 * or race makes us see a 64-bit instruction here the sdl/sdr
2193 * would blow up, so for now we don't handle unaligned 64-bit
2194 * instructions on 32-bit kernels.
2195 */
2196 if (!access_ok(VERIFY_WRITE, addr, 8))
2197 goto sigbus;
2198
2199 MIPS16e_compute_return_epc(regs, &oldinst);
2200 value = regs->regs[reg];
2201 StoreDW(addr, value, res);
2202 if (res)
2203 goto fault;
2204 break;
2205 #endif /* CONFIG_64BIT */
2206
2207 /* Cannot handle 64-bit instructions in 32-bit kernel */
2208 goto sigill;
2209
2210 default:
2211 /*
2212 * Pheeee... We encountered an yet unknown instruction or
2213 * cache coherence problem. Die sucker, die ...
2214 */
2215 goto sigill;
2216 }
2217
2218 #ifdef CONFIG_DEBUG_FS
2219 unaligned_instructions++;
2220 #endif
2221
2222 return;
2223
2224 fault:
2225 /* roll back jump/branch */
2226 regs->cp0_epc = origpc;
2227 regs->regs[31] = orig31;
2228 /* Did we have an exception handler installed? */
2229 if (fixup_exception(regs))
2230 return;
2231
2232 die_if_kernel("Unhandled kernel unaligned access", regs);
2233 force_sig(SIGSEGV, current);
2234
2235 return;
2236
2237 sigbus:
2238 die_if_kernel("Unhandled kernel unaligned access", regs);
2239 force_sig(SIGBUS, current);
2240
2241 return;
2242
2243 sigill:
2244 die_if_kernel
2245 ("Unhandled kernel unaligned access or invalid instruction", regs);
2246 force_sig(SIGILL, current);
2247 }
2248
do_ade(struct pt_regs * regs)2249 asmlinkage void do_ade(struct pt_regs *regs)
2250 {
2251 enum ctx_state prev_state;
2252 unsigned int __user *pc;
2253 mm_segment_t seg;
2254
2255 prev_state = exception_enter();
2256 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS,
2257 1, regs, regs->cp0_badvaddr);
2258 /*
2259 * Did we catch a fault trying to load an instruction?
2260 */
2261 if (regs->cp0_badvaddr == regs->cp0_epc)
2262 goto sigbus;
2263
2264 if (user_mode(regs) && !test_thread_flag(TIF_FIXADE))
2265 goto sigbus;
2266 if (unaligned_action == UNALIGNED_ACTION_SIGNAL)
2267 goto sigbus;
2268
2269 /*
2270 * Do branch emulation only if we didn't forward the exception.
2271 * This is all so but ugly ...
2272 */
2273
2274 /*
2275 * Are we running in microMIPS mode?
2276 */
2277 if (get_isa16_mode(regs->cp0_epc)) {
2278 /*
2279 * Did we catch a fault trying to load an instruction in
2280 * 16-bit mode?
2281 */
2282 if (regs->cp0_badvaddr == msk_isa16_mode(regs->cp0_epc))
2283 goto sigbus;
2284 if (unaligned_action == UNALIGNED_ACTION_SHOW)
2285 show_registers(regs);
2286
2287 if (cpu_has_mmips) {
2288 seg = get_fs();
2289 if (!user_mode(regs))
2290 set_fs(KERNEL_DS);
2291 emulate_load_store_microMIPS(regs,
2292 (void __user *)regs->cp0_badvaddr);
2293 set_fs(seg);
2294
2295 return;
2296 }
2297
2298 if (cpu_has_mips16) {
2299 seg = get_fs();
2300 if (!user_mode(regs))
2301 set_fs(KERNEL_DS);
2302 emulate_load_store_MIPS16e(regs,
2303 (void __user *)regs->cp0_badvaddr);
2304 set_fs(seg);
2305
2306 return;
2307 }
2308
2309 goto sigbus;
2310 }
2311
2312 if (unaligned_action == UNALIGNED_ACTION_SHOW)
2313 show_registers(regs);
2314 pc = (unsigned int __user *)exception_epc(regs);
2315
2316 seg = get_fs();
2317 if (!user_mode(regs))
2318 set_fs(KERNEL_DS);
2319 emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc);
2320 set_fs(seg);
2321
2322 return;
2323
2324 sigbus:
2325 die_if_kernel("Kernel unaligned instruction access", regs);
2326 force_sig(SIGBUS, current);
2327
2328 /*
2329 * XXX On return from the signal handler we should advance the epc
2330 */
2331 exception_exit(prev_state);
2332 }
2333
2334 #ifdef CONFIG_DEBUG_FS
debugfs_unaligned(void)2335 static int __init debugfs_unaligned(void)
2336 {
2337 struct dentry *d;
2338
2339 if (!mips_debugfs_dir)
2340 return -ENODEV;
2341 d = debugfs_create_u32("unaligned_instructions", S_IRUGO,
2342 mips_debugfs_dir, &unaligned_instructions);
2343 if (!d)
2344 return -ENOMEM;
2345 d = debugfs_create_u32("unaligned_action", S_IRUGO | S_IWUSR,
2346 mips_debugfs_dir, &unaligned_action);
2347 if (!d)
2348 return -ENOMEM;
2349 return 0;
2350 }
2351 arch_initcall(debugfs_unaligned);
2352 #endif
2353