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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
98enum {
99 UNALIGNED_ACTION_QUIET,
100 UNALIGNED_ACTION_SIGNAL,
101 UNALIGNED_ACTION_SHOW,
102};
103#ifdef CONFIG_DEBUG_FS
104static u32 unaligned_instructions;
105static u32 unaligned_action;
106#else
107#define unaligned_action UNALIGNED_ACTION_QUIET
108#endif
109extern void show_registers(struct pt_regs *regs);
110
111#ifdef __BIG_ENDIAN
112#define _LoadHW(addr, value, res, type) \
113do { \
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) \
136do { \
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) \
158do { \
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) \
193do { \
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) \
218do { \
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) \
240do { \
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) \
262do { \
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) \
295do { \
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) \
347do { \
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) \
371do { \
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) \
391do { \
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) \
412do { \
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) \
443do { \
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) \
491do { \
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) \
514do { \
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) \
536do { \
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) \
572do { \
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) \
597do { \
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) \
619do { \
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) \
641do { \
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) \
674do { \
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) \
724do { \
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) \
748do { \
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) \
768do { \
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) \
790do { \
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) \
821do { \
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
883static 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
1359fault:
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
1372sigbus:
1373 die_if_kernel("Unhandled kernel unaligned access", regs);
1374 force_sig(SIGBUS);
1375
1376 return;
1377
1378sigill:
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. */
1385const int reg16to32[] = { 16, 17, 2, 3, 4, 5, 6, 7 };
1386
1387/* Recode table from 16-bit STORE register notation to 32-bit GPR. */
1388static const int reg16to32st[] = { 0, 17, 2, 3, 4, 5, 6, 7 };
1389
1390static 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
1733fpu_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
1861loadHW:
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
1871loadHWU:
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
1881loadW:
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
1891loadWU:
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
1913loadDW:
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
1935storeHW:
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
1945storeW:
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
1955storeDW:
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
1977success:
1978 regs->cp0_epc = contpc; /* advance or branch */
1979
1980#ifdef CONFIG_DEBUG_FS
1981 unaligned_instructions++;
1982#endif
1983 return;
1984
1985fault:
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
1998sigbus:
1999 die_if_kernel("Unhandled kernel unaligned access", regs);
2000 force_sig(SIGBUS);
2001
2002 return;
2003
2004sigill:
2005 die_if_kernel
2006 ("Unhandled kernel unaligned access or invalid instruction", regs);
2007 force_sig(SIGILL);
2008}
2009
2010static 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:
2180loadDW:
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:
2228writeDW:
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
2265fault:
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
2278sigbus:
2279 die_if_kernel("Unhandled kernel unaligned access", regs);
2280 force_sig(SIGBUS);
2281
2282 return;
2283
2284sigill:
2285 die_if_kernel
2286 ("Unhandled kernel unaligned access or invalid instruction", regs);
2287 force_sig(SIGILL);
2288}
2289
2290asmlinkage 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
2365sigbus:
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
2376static 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}
2384arch_initcall(debugfs_unaligned);
2385#endif
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/fpu.h>
89#include <asm/fpu_emulator.h>
90#include <asm/inst.h>
91#include <asm/uaccess.h>
92#include <asm/fpu.h>
93#include <asm/fpu_emulator.h>
94
95#define STR(x) __STR(x)
96#define __STR(x) #x
97
98enum {
99 UNALIGNED_ACTION_QUIET,
100 UNALIGNED_ACTION_SIGNAL,
101 UNALIGNED_ACTION_SHOW,
102};
103#ifdef CONFIG_DEBUG_FS
104static u32 unaligned_instructions;
105static u32 unaligned_action;
106#else
107#define unaligned_action UNALIGNED_ACTION_QUIET
108#endif
109extern void show_registers(struct pt_regs *regs);
110
111#ifdef __BIG_ENDIAN
112#define LoadHW(addr, value, res) \
113 __asm__ __volatile__ (".set\tnoat\n" \
114 "1:\t"user_lb("%0", "0(%2)")"\n" \
115 "2:\t"user_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
132#define LoadW(addr, value, res) \
133 __asm__ __volatile__ ( \
134 "1:\t"user_lwl("%0", "(%2)")"\n" \
135 "2:\t"user_lwr("%0", "3(%2)")"\n\t" \
136 "li\t%1, 0\n" \
137 "3:\n\t" \
138 ".insn\n\t" \
139 ".section\t.fixup,\"ax\"\n\t" \
140 "4:\tli\t%1, %3\n\t" \
141 "j\t3b\n\t" \
142 ".previous\n\t" \
143 ".section\t__ex_table,\"a\"\n\t" \
144 STR(PTR)"\t1b, 4b\n\t" \
145 STR(PTR)"\t2b, 4b\n\t" \
146 ".previous" \
147 : "=&r" (value), "=r" (res) \
148 : "r" (addr), "i" (-EFAULT));
149
150#define LoadHWU(addr, value, res) \
151 __asm__ __volatile__ ( \
152 ".set\tnoat\n" \
153 "1:\t"user_lbu("%0", "0(%2)")"\n" \
154 "2:\t"user_lbu("$1", "1(%2)")"\n\t" \
155 "sll\t%0, 0x8\n\t" \
156 "or\t%0, $1\n\t" \
157 "li\t%1, 0\n" \
158 "3:\n\t" \
159 ".insn\n\t" \
160 ".set\tat\n\t" \
161 ".section\t.fixup,\"ax\"\n\t" \
162 "4:\tli\t%1, %3\n\t" \
163 "j\t3b\n\t" \
164 ".previous\n\t" \
165 ".section\t__ex_table,\"a\"\n\t" \
166 STR(PTR)"\t1b, 4b\n\t" \
167 STR(PTR)"\t2b, 4b\n\t" \
168 ".previous" \
169 : "=&r" (value), "=r" (res) \
170 : "r" (addr), "i" (-EFAULT));
171
172#define LoadWU(addr, value, res) \
173 __asm__ __volatile__ ( \
174 "1:\t"user_lwl("%0", "(%2)")"\n" \
175 "2:\t"user_lwr("%0", "3(%2)")"\n\t" \
176 "dsll\t%0, %0, 32\n\t" \
177 "dsrl\t%0, %0, 32\n\t" \
178 "li\t%1, 0\n" \
179 "3:\n\t" \
180 ".insn\n\t" \
181 "\t.section\t.fixup,\"ax\"\n\t" \
182 "4:\tli\t%1, %3\n\t" \
183 "j\t3b\n\t" \
184 ".previous\n\t" \
185 ".section\t__ex_table,\"a\"\n\t" \
186 STR(PTR)"\t1b, 4b\n\t" \
187 STR(PTR)"\t2b, 4b\n\t" \
188 ".previous" \
189 : "=&r" (value), "=r" (res) \
190 : "r" (addr), "i" (-EFAULT));
191
192#define LoadDW(addr, value, res) \
193 __asm__ __volatile__ ( \
194 "1:\tldl\t%0, (%2)\n" \
195 "2:\tldr\t%0, 7(%2)\n\t" \
196 "li\t%1, 0\n" \
197 "3:\n\t" \
198 ".insn\n\t" \
199 "\t.section\t.fixup,\"ax\"\n\t" \
200 "4:\tli\t%1, %3\n\t" \
201 "j\t3b\n\t" \
202 ".previous\n\t" \
203 ".section\t__ex_table,\"a\"\n\t" \
204 STR(PTR)"\t1b, 4b\n\t" \
205 STR(PTR)"\t2b, 4b\n\t" \
206 ".previous" \
207 : "=&r" (value), "=r" (res) \
208 : "r" (addr), "i" (-EFAULT));
209
210#define StoreHW(addr, value, res) \
211 __asm__ __volatile__ ( \
212 ".set\tnoat\n" \
213 "1:\t"user_sb("%1", "1(%2)")"\n" \
214 "srl\t$1, %1, 0x8\n" \
215 "2:\t"user_sb("$1", "0(%2)")"\n" \
216 ".set\tat\n\t" \
217 "li\t%0, 0\n" \
218 "3:\n\t" \
219 ".insn\n\t" \
220 ".section\t.fixup,\"ax\"\n\t" \
221 "4:\tli\t%0, %3\n\t" \
222 "j\t3b\n\t" \
223 ".previous\n\t" \
224 ".section\t__ex_table,\"a\"\n\t" \
225 STR(PTR)"\t1b, 4b\n\t" \
226 STR(PTR)"\t2b, 4b\n\t" \
227 ".previous" \
228 : "=r" (res) \
229 : "r" (value), "r" (addr), "i" (-EFAULT));
230
231#define StoreW(addr, value, res) \
232 __asm__ __volatile__ ( \
233 "1:\t"user_swl("%1", "(%2)")"\n" \
234 "2:\t"user_swr("%1", "3(%2)")"\n\t" \
235 "li\t%0, 0\n" \
236 "3:\n\t" \
237 ".insn\n\t" \
238 ".section\t.fixup,\"ax\"\n\t" \
239 "4:\tli\t%0, %3\n\t" \
240 "j\t3b\n\t" \
241 ".previous\n\t" \
242 ".section\t__ex_table,\"a\"\n\t" \
243 STR(PTR)"\t1b, 4b\n\t" \
244 STR(PTR)"\t2b, 4b\n\t" \
245 ".previous" \
246 : "=r" (res) \
247 : "r" (value), "r" (addr), "i" (-EFAULT));
248
249#define StoreDW(addr, value, res) \
250 __asm__ __volatile__ ( \
251 "1:\tsdl\t%1,(%2)\n" \
252 "2:\tsdr\t%1, 7(%2)\n\t" \
253 "li\t%0, 0\n" \
254 "3:\n\t" \
255 ".insn\n\t" \
256 ".section\t.fixup,\"ax\"\n\t" \
257 "4:\tli\t%0, %3\n\t" \
258 "j\t3b\n\t" \
259 ".previous\n\t" \
260 ".section\t__ex_table,\"a\"\n\t" \
261 STR(PTR)"\t1b, 4b\n\t" \
262 STR(PTR)"\t2b, 4b\n\t" \
263 ".previous" \
264 : "=r" (res) \
265 : "r" (value), "r" (addr), "i" (-EFAULT));
266#endif
267
268#ifdef __LITTLE_ENDIAN
269#define LoadHW(addr, value, res) \
270 __asm__ __volatile__ (".set\tnoat\n" \
271 "1:\t"user_lb("%0", "1(%2)")"\n" \
272 "2:\t"user_lbu("$1", "0(%2)")"\n\t" \
273 "sll\t%0, 0x8\n\t" \
274 "or\t%0, $1\n\t" \
275 "li\t%1, 0\n" \
276 "3:\t.set\tat\n\t" \
277 ".insn\n\t" \
278 ".section\t.fixup,\"ax\"\n\t" \
279 "4:\tli\t%1, %3\n\t" \
280 "j\t3b\n\t" \
281 ".previous\n\t" \
282 ".section\t__ex_table,\"a\"\n\t" \
283 STR(PTR)"\t1b, 4b\n\t" \
284 STR(PTR)"\t2b, 4b\n\t" \
285 ".previous" \
286 : "=&r" (value), "=r" (res) \
287 : "r" (addr), "i" (-EFAULT));
288
289#define LoadW(addr, value, res) \
290 __asm__ __volatile__ ( \
291 "1:\t"user_lwl("%0", "3(%2)")"\n" \
292 "2:\t"user_lwr("%0", "(%2)")"\n\t" \
293 "li\t%1, 0\n" \
294 "3:\n\t" \
295 ".insn\n\t" \
296 ".section\t.fixup,\"ax\"\n\t" \
297 "4:\tli\t%1, %3\n\t" \
298 "j\t3b\n\t" \
299 ".previous\n\t" \
300 ".section\t__ex_table,\"a\"\n\t" \
301 STR(PTR)"\t1b, 4b\n\t" \
302 STR(PTR)"\t2b, 4b\n\t" \
303 ".previous" \
304 : "=&r" (value), "=r" (res) \
305 : "r" (addr), "i" (-EFAULT));
306
307#define LoadHWU(addr, value, res) \
308 __asm__ __volatile__ ( \
309 ".set\tnoat\n" \
310 "1:\t"user_lbu("%0", "1(%2)")"\n" \
311 "2:\t"user_lbu("$1", "0(%2)")"\n\t" \
312 "sll\t%0, 0x8\n\t" \
313 "or\t%0, $1\n\t" \
314 "li\t%1, 0\n" \
315 "3:\n\t" \
316 ".insn\n\t" \
317 ".set\tat\n\t" \
318 ".section\t.fixup,\"ax\"\n\t" \
319 "4:\tli\t%1, %3\n\t" \
320 "j\t3b\n\t" \
321 ".previous\n\t" \
322 ".section\t__ex_table,\"a\"\n\t" \
323 STR(PTR)"\t1b, 4b\n\t" \
324 STR(PTR)"\t2b, 4b\n\t" \
325 ".previous" \
326 : "=&r" (value), "=r" (res) \
327 : "r" (addr), "i" (-EFAULT));
328
329#define LoadWU(addr, value, res) \
330 __asm__ __volatile__ ( \
331 "1:\t"user_lwl("%0", "3(%2)")"\n" \
332 "2:\t"user_lwr("%0", "(%2)")"\n\t" \
333 "dsll\t%0, %0, 32\n\t" \
334 "dsrl\t%0, %0, 32\n\t" \
335 "li\t%1, 0\n" \
336 "3:\n\t" \
337 ".insn\n\t" \
338 "\t.section\t.fixup,\"ax\"\n\t" \
339 "4:\tli\t%1, %3\n\t" \
340 "j\t3b\n\t" \
341 ".previous\n\t" \
342 ".section\t__ex_table,\"a\"\n\t" \
343 STR(PTR)"\t1b, 4b\n\t" \
344 STR(PTR)"\t2b, 4b\n\t" \
345 ".previous" \
346 : "=&r" (value), "=r" (res) \
347 : "r" (addr), "i" (-EFAULT));
348
349#define LoadDW(addr, value, res) \
350 __asm__ __volatile__ ( \
351 "1:\tldl\t%0, 7(%2)\n" \
352 "2:\tldr\t%0, (%2)\n\t" \
353 "li\t%1, 0\n" \
354 "3:\n\t" \
355 ".insn\n\t" \
356 "\t.section\t.fixup,\"ax\"\n\t" \
357 "4:\tli\t%1, %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" (value), "=r" (res) \
365 : "r" (addr), "i" (-EFAULT));
366
367#define StoreHW(addr, value, res) \
368 __asm__ __volatile__ ( \
369 ".set\tnoat\n" \
370 "1:\t"user_sb("%1", "0(%2)")"\n" \
371 "srl\t$1,%1, 0x8\n" \
372 "2:\t"user_sb("$1", "1(%2)")"\n" \
373 ".set\tat\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
388#define StoreW(addr, value, res) \
389 __asm__ __volatile__ ( \
390 "1:\t"user_swl("%1", "3(%2)")"\n" \
391 "2:\t"user_swr("%1", "(%2)")"\n\t" \
392 "li\t%0, 0\n" \
393 "3:\n\t" \
394 ".insn\n\t" \
395 ".section\t.fixup,\"ax\"\n\t" \
396 "4:\tli\t%0, %3\n\t" \
397 "j\t3b\n\t" \
398 ".previous\n\t" \
399 ".section\t__ex_table,\"a\"\n\t" \
400 STR(PTR)"\t1b, 4b\n\t" \
401 STR(PTR)"\t2b, 4b\n\t" \
402 ".previous" \
403 : "=r" (res) \
404 : "r" (value), "r" (addr), "i" (-EFAULT));
405
406#define StoreDW(addr, value, res) \
407 __asm__ __volatile__ ( \
408 "1:\tsdl\t%1, 7(%2)\n" \
409 "2:\tsdr\t%1, (%2)\n\t" \
410 "li\t%0, 0\n" \
411 "3:\n\t" \
412 ".insn\n\t" \
413 ".section\t.fixup,\"ax\"\n\t" \
414 "4:\tli\t%0, %3\n\t" \
415 "j\t3b\n\t" \
416 ".previous\n\t" \
417 ".section\t__ex_table,\"a\"\n\t" \
418 STR(PTR)"\t1b, 4b\n\t" \
419 STR(PTR)"\t2b, 4b\n\t" \
420 ".previous" \
421 : "=r" (res) \
422 : "r" (value), "r" (addr), "i" (-EFAULT));
423#endif
424
425static void emulate_load_store_insn(struct pt_regs *regs,
426 void __user *addr, unsigned int __user *pc)
427{
428 union mips_instruction insn;
429 unsigned long value;
430 unsigned int res;
431 unsigned long origpc;
432 unsigned long orig31;
433 void __user *fault_addr = NULL;
434#ifdef CONFIG_EVA
435 mm_segment_t seg;
436#endif
437 origpc = (unsigned long)pc;
438 orig31 = regs->regs[31];
439
440 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
441
442 /*
443 * This load never faults.
444 */
445 __get_user(insn.word, pc);
446
447 switch (insn.i_format.opcode) {
448 /*
449 * These are instructions that a compiler doesn't generate. We
450 * can assume therefore that the code is MIPS-aware and
451 * really buggy. Emulating these instructions would break the
452 * semantics anyway.
453 */
454 case ll_op:
455 case lld_op:
456 case sc_op:
457 case scd_op:
458
459 /*
460 * For these instructions the only way to create an address
461 * error is an attempted access to kernel/supervisor address
462 * space.
463 */
464 case ldl_op:
465 case ldr_op:
466 case lwl_op:
467 case lwr_op:
468 case sdl_op:
469 case sdr_op:
470 case swl_op:
471 case swr_op:
472 case lb_op:
473 case lbu_op:
474 case sb_op:
475 goto sigbus;
476
477 /*
478 * The remaining opcodes are the ones that are really of
479 * interest.
480 */
481#ifdef CONFIG_EVA
482 case spec3_op:
483 /*
484 * we can land here only from kernel accessing user memory,
485 * so we need to "switch" the address limit to user space, so
486 * address check can work properly.
487 */
488 seg = get_fs();
489 set_fs(USER_DS);
490 switch (insn.spec3_format.func) {
491 case lhe_op:
492 if (!access_ok(VERIFY_READ, addr, 2)) {
493 set_fs(seg);
494 goto sigbus;
495 }
496 LoadHW(addr, value, res);
497 if (res) {
498 set_fs(seg);
499 goto fault;
500 }
501 compute_return_epc(regs);
502 regs->regs[insn.spec3_format.rt] = value;
503 break;
504 case lwe_op:
505 if (!access_ok(VERIFY_READ, addr, 4)) {
506 set_fs(seg);
507 goto sigbus;
508 }
509 LoadW(addr, value, res);
510 if (res) {
511 set_fs(seg);
512 goto fault;
513 }
514 compute_return_epc(regs);
515 regs->regs[insn.spec3_format.rt] = value;
516 break;
517 case lhue_op:
518 if (!access_ok(VERIFY_READ, addr, 2)) {
519 set_fs(seg);
520 goto sigbus;
521 }
522 LoadHWU(addr, value, res);
523 if (res) {
524 set_fs(seg);
525 goto fault;
526 }
527 compute_return_epc(regs);
528 regs->regs[insn.spec3_format.rt] = value;
529 break;
530 case she_op:
531 if (!access_ok(VERIFY_WRITE, addr, 2)) {
532 set_fs(seg);
533 goto sigbus;
534 }
535 compute_return_epc(regs);
536 value = regs->regs[insn.spec3_format.rt];
537 StoreHW(addr, value, res);
538 if (res) {
539 set_fs(seg);
540 goto fault;
541 }
542 break;
543 case swe_op:
544 if (!access_ok(VERIFY_WRITE, addr, 4)) {
545 set_fs(seg);
546 goto sigbus;
547 }
548 compute_return_epc(regs);
549 value = regs->regs[insn.spec3_format.rt];
550 StoreW(addr, value, res);
551 if (res) {
552 set_fs(seg);
553 goto fault;
554 }
555 break;
556 default:
557 set_fs(seg);
558 goto sigill;
559 }
560 set_fs(seg);
561 break;
562#endif
563 case lh_op:
564 if (!access_ok(VERIFY_READ, addr, 2))
565 goto sigbus;
566
567 LoadHW(addr, value, res);
568 if (res)
569 goto fault;
570 compute_return_epc(regs);
571 regs->regs[insn.i_format.rt] = value;
572 break;
573
574 case lw_op:
575 if (!access_ok(VERIFY_READ, addr, 4))
576 goto sigbus;
577
578 LoadW(addr, value, res);
579 if (res)
580 goto fault;
581 compute_return_epc(regs);
582 regs->regs[insn.i_format.rt] = value;
583 break;
584
585 case lhu_op:
586 if (!access_ok(VERIFY_READ, addr, 2))
587 goto sigbus;
588
589 LoadHWU(addr, value, res);
590 if (res)
591 goto fault;
592 compute_return_epc(regs);
593 regs->regs[insn.i_format.rt] = value;
594 break;
595
596 case lwu_op:
597#ifdef CONFIG_64BIT
598 /*
599 * A 32-bit kernel might be running on a 64-bit processor. But
600 * if we're on a 32-bit processor and an i-cache incoherency
601 * or race makes us see a 64-bit instruction here the sdl/sdr
602 * would blow up, so for now we don't handle unaligned 64-bit
603 * instructions on 32-bit kernels.
604 */
605 if (!access_ok(VERIFY_READ, addr, 4))
606 goto sigbus;
607
608 LoadWU(addr, value, res);
609 if (res)
610 goto fault;
611 compute_return_epc(regs);
612 regs->regs[insn.i_format.rt] = value;
613 break;
614#endif /* CONFIG_64BIT */
615
616 /* Cannot handle 64-bit instructions in 32-bit kernel */
617 goto sigill;
618
619 case ld_op:
620#ifdef CONFIG_64BIT
621 /*
622 * A 32-bit kernel might be running on a 64-bit processor. But
623 * if we're on a 32-bit processor and an i-cache incoherency
624 * or race makes us see a 64-bit instruction here the sdl/sdr
625 * would blow up, so for now we don't handle unaligned 64-bit
626 * instructions on 32-bit kernels.
627 */
628 if (!access_ok(VERIFY_READ, addr, 8))
629 goto sigbus;
630
631 LoadDW(addr, value, res);
632 if (res)
633 goto fault;
634 compute_return_epc(regs);
635 regs->regs[insn.i_format.rt] = value;
636 break;
637#endif /* CONFIG_64BIT */
638
639 /* Cannot handle 64-bit instructions in 32-bit kernel */
640 goto sigill;
641
642 case sh_op:
643 if (!access_ok(VERIFY_WRITE, addr, 2))
644 goto sigbus;
645
646 compute_return_epc(regs);
647 value = regs->regs[insn.i_format.rt];
648 StoreHW(addr, value, res);
649 if (res)
650 goto fault;
651 break;
652
653 case sw_op:
654 if (!access_ok(VERIFY_WRITE, addr, 4))
655 goto sigbus;
656
657 compute_return_epc(regs);
658 value = regs->regs[insn.i_format.rt];
659 StoreW(addr, value, res);
660 if (res)
661 goto fault;
662 break;
663
664 case sd_op:
665#ifdef CONFIG_64BIT
666 /*
667 * A 32-bit kernel might be running on a 64-bit processor. But
668 * if we're on a 32-bit processor and an i-cache incoherency
669 * or race makes us see a 64-bit instruction here the sdl/sdr
670 * would blow up, so for now we don't handle unaligned 64-bit
671 * instructions on 32-bit kernels.
672 */
673 if (!access_ok(VERIFY_WRITE, addr, 8))
674 goto sigbus;
675
676 compute_return_epc(regs);
677 value = regs->regs[insn.i_format.rt];
678 StoreDW(addr, value, res);
679 if (res)
680 goto fault;
681 break;
682#endif /* CONFIG_64BIT */
683
684 /* Cannot handle 64-bit instructions in 32-bit kernel */
685 goto sigill;
686
687 case lwc1_op:
688 case ldc1_op:
689 case swc1_op:
690 case sdc1_op:
691 die_if_kernel("Unaligned FP access in kernel code", regs);
692 BUG_ON(!used_math());
693 BUG_ON(!is_fpu_owner());
694
695 lose_fpu(1); /* Save FPU state for the emulator. */
696 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
697 &fault_addr);
698 own_fpu(1); /* Restore FPU state. */
699
700 /* Signal if something went wrong. */
701 process_fpemu_return(res, fault_addr);
702
703 if (res == 0)
704 break;
705 return;
706
707 /*
708 * COP2 is available to implementor for application specific use.
709 * It's up to applications to register a notifier chain and do
710 * whatever they have to do, including possible sending of signals.
711 */
712 case lwc2_op:
713 cu2_notifier_call_chain(CU2_LWC2_OP, regs);
714 break;
715
716 case ldc2_op:
717 cu2_notifier_call_chain(CU2_LDC2_OP, regs);
718 break;
719
720 case swc2_op:
721 cu2_notifier_call_chain(CU2_SWC2_OP, regs);
722 break;
723
724 case sdc2_op:
725 cu2_notifier_call_chain(CU2_SDC2_OP, regs);
726 break;
727
728 default:
729 /*
730 * Pheeee... We encountered an yet unknown instruction or
731 * cache coherence problem. Die sucker, die ...
732 */
733 goto sigill;
734 }
735
736#ifdef CONFIG_DEBUG_FS
737 unaligned_instructions++;
738#endif
739
740 return;
741
742fault:
743 /* roll back jump/branch */
744 regs->cp0_epc = origpc;
745 regs->regs[31] = orig31;
746 /* Did we have an exception handler installed? */
747 if (fixup_exception(regs))
748 return;
749
750 die_if_kernel("Unhandled kernel unaligned access", regs);
751 force_sig(SIGSEGV, current);
752
753 return;
754
755sigbus:
756 die_if_kernel("Unhandled kernel unaligned access", regs);
757 force_sig(SIGBUS, current);
758
759 return;
760
761sigill:
762 die_if_kernel
763 ("Unhandled kernel unaligned access or invalid instruction", regs);
764 force_sig(SIGILL, current);
765}
766
767/* Recode table from 16-bit register notation to 32-bit GPR. */
768const int reg16to32[] = { 16, 17, 2, 3, 4, 5, 6, 7 };
769
770/* Recode table from 16-bit STORE register notation to 32-bit GPR. */
771const int reg16to32st[] = { 0, 17, 2, 3, 4, 5, 6, 7 };
772
773static void emulate_load_store_microMIPS(struct pt_regs *regs,
774 void __user *addr)
775{
776 unsigned long value;
777 unsigned int res;
778 int i;
779 unsigned int reg = 0, rvar;
780 unsigned long orig31;
781 u16 __user *pc16;
782 u16 halfword;
783 unsigned int word;
784 unsigned long origpc, contpc;
785 union mips_instruction insn;
786 struct mm_decoded_insn mminsn;
787 void __user *fault_addr = NULL;
788
789 origpc = regs->cp0_epc;
790 orig31 = regs->regs[31];
791
792 mminsn.micro_mips_mode = 1;
793
794 /*
795 * This load never faults.
796 */
797 pc16 = (unsigned short __user *)msk_isa16_mode(regs->cp0_epc);
798 __get_user(halfword, pc16);
799 pc16++;
800 contpc = regs->cp0_epc + 2;
801 word = ((unsigned int)halfword << 16);
802 mminsn.pc_inc = 2;
803
804 if (!mm_insn_16bit(halfword)) {
805 __get_user(halfword, pc16);
806 pc16++;
807 contpc = regs->cp0_epc + 4;
808 mminsn.pc_inc = 4;
809 word |= halfword;
810 }
811 mminsn.insn = word;
812
813 if (get_user(halfword, pc16))
814 goto fault;
815 mminsn.next_pc_inc = 2;
816 word = ((unsigned int)halfword << 16);
817
818 if (!mm_insn_16bit(halfword)) {
819 pc16++;
820 if (get_user(halfword, pc16))
821 goto fault;
822 mminsn.next_pc_inc = 4;
823 word |= halfword;
824 }
825 mminsn.next_insn = word;
826
827 insn = (union mips_instruction)(mminsn.insn);
828 if (mm_isBranchInstr(regs, mminsn, &contpc))
829 insn = (union mips_instruction)(mminsn.next_insn);
830
831 /* Parse instruction to find what to do */
832
833 switch (insn.mm_i_format.opcode) {
834
835 case mm_pool32a_op:
836 switch (insn.mm_x_format.func) {
837 case mm_lwxs_op:
838 reg = insn.mm_x_format.rd;
839 goto loadW;
840 }
841
842 goto sigbus;
843
844 case mm_pool32b_op:
845 switch (insn.mm_m_format.func) {
846 case mm_lwp_func:
847 reg = insn.mm_m_format.rd;
848 if (reg == 31)
849 goto sigbus;
850
851 if (!access_ok(VERIFY_READ, addr, 8))
852 goto sigbus;
853
854 LoadW(addr, value, res);
855 if (res)
856 goto fault;
857 regs->regs[reg] = value;
858 addr += 4;
859 LoadW(addr, value, res);
860 if (res)
861 goto fault;
862 regs->regs[reg + 1] = value;
863 goto success;
864
865 case mm_swp_func:
866 reg = insn.mm_m_format.rd;
867 if (reg == 31)
868 goto sigbus;
869
870 if (!access_ok(VERIFY_WRITE, addr, 8))
871 goto sigbus;
872
873 value = regs->regs[reg];
874 StoreW(addr, value, res);
875 if (res)
876 goto fault;
877 addr += 4;
878 value = regs->regs[reg + 1];
879 StoreW(addr, value, res);
880 if (res)
881 goto fault;
882 goto success;
883
884 case mm_ldp_func:
885#ifdef CONFIG_64BIT
886 reg = insn.mm_m_format.rd;
887 if (reg == 31)
888 goto sigbus;
889
890 if (!access_ok(VERIFY_READ, addr, 16))
891 goto sigbus;
892
893 LoadDW(addr, value, res);
894 if (res)
895 goto fault;
896 regs->regs[reg] = value;
897 addr += 8;
898 LoadDW(addr, value, res);
899 if (res)
900 goto fault;
901 regs->regs[reg + 1] = value;
902 goto success;
903#endif /* CONFIG_64BIT */
904
905 goto sigill;
906
907 case mm_sdp_func:
908#ifdef CONFIG_64BIT
909 reg = insn.mm_m_format.rd;
910 if (reg == 31)
911 goto sigbus;
912
913 if (!access_ok(VERIFY_WRITE, addr, 16))
914 goto sigbus;
915
916 value = regs->regs[reg];
917 StoreDW(addr, value, res);
918 if (res)
919 goto fault;
920 addr += 8;
921 value = regs->regs[reg + 1];
922 StoreDW(addr, value, res);
923 if (res)
924 goto fault;
925 goto success;
926#endif /* CONFIG_64BIT */
927
928 goto sigill;
929
930 case mm_lwm32_func:
931 reg = insn.mm_m_format.rd;
932 rvar = reg & 0xf;
933 if ((rvar > 9) || !reg)
934 goto sigill;
935 if (reg & 0x10) {
936 if (!access_ok
937 (VERIFY_READ, addr, 4 * (rvar + 1)))
938 goto sigbus;
939 } else {
940 if (!access_ok(VERIFY_READ, addr, 4 * rvar))
941 goto sigbus;
942 }
943 if (rvar == 9)
944 rvar = 8;
945 for (i = 16; rvar; rvar--, i++) {
946 LoadW(addr, value, res);
947 if (res)
948 goto fault;
949 addr += 4;
950 regs->regs[i] = value;
951 }
952 if ((reg & 0xf) == 9) {
953 LoadW(addr, value, res);
954 if (res)
955 goto fault;
956 addr += 4;
957 regs->regs[30] = value;
958 }
959 if (reg & 0x10) {
960 LoadW(addr, value, res);
961 if (res)
962 goto fault;
963 regs->regs[31] = value;
964 }
965 goto success;
966
967 case mm_swm32_func:
968 reg = insn.mm_m_format.rd;
969 rvar = reg & 0xf;
970 if ((rvar > 9) || !reg)
971 goto sigill;
972 if (reg & 0x10) {
973 if (!access_ok
974 (VERIFY_WRITE, addr, 4 * (rvar + 1)))
975 goto sigbus;
976 } else {
977 if (!access_ok(VERIFY_WRITE, addr, 4 * rvar))
978 goto sigbus;
979 }
980 if (rvar == 9)
981 rvar = 8;
982 for (i = 16; rvar; rvar--, i++) {
983 value = regs->regs[i];
984 StoreW(addr, value, res);
985 if (res)
986 goto fault;
987 addr += 4;
988 }
989 if ((reg & 0xf) == 9) {
990 value = regs->regs[30];
991 StoreW(addr, value, res);
992 if (res)
993 goto fault;
994 addr += 4;
995 }
996 if (reg & 0x10) {
997 value = regs->regs[31];
998 StoreW(addr, value, res);
999 if (res)
1000 goto fault;
1001 }
1002 goto success;
1003
1004 case mm_ldm_func:
1005#ifdef CONFIG_64BIT
1006 reg = insn.mm_m_format.rd;
1007 rvar = reg & 0xf;
1008 if ((rvar > 9) || !reg)
1009 goto sigill;
1010 if (reg & 0x10) {
1011 if (!access_ok
1012 (VERIFY_READ, addr, 8 * (rvar + 1)))
1013 goto sigbus;
1014 } else {
1015 if (!access_ok(VERIFY_READ, addr, 8 * rvar))
1016 goto sigbus;
1017 }
1018 if (rvar == 9)
1019 rvar = 8;
1020
1021 for (i = 16; rvar; rvar--, i++) {
1022 LoadDW(addr, value, res);
1023 if (res)
1024 goto fault;
1025 addr += 4;
1026 regs->regs[i] = value;
1027 }
1028 if ((reg & 0xf) == 9) {
1029 LoadDW(addr, value, res);
1030 if (res)
1031 goto fault;
1032 addr += 8;
1033 regs->regs[30] = value;
1034 }
1035 if (reg & 0x10) {
1036 LoadDW(addr, value, res);
1037 if (res)
1038 goto fault;
1039 regs->regs[31] = value;
1040 }
1041 goto success;
1042#endif /* CONFIG_64BIT */
1043
1044 goto sigill;
1045
1046 case mm_sdm_func:
1047#ifdef CONFIG_64BIT
1048 reg = insn.mm_m_format.rd;
1049 rvar = reg & 0xf;
1050 if ((rvar > 9) || !reg)
1051 goto sigill;
1052 if (reg & 0x10) {
1053 if (!access_ok
1054 (VERIFY_WRITE, addr, 8 * (rvar + 1)))
1055 goto sigbus;
1056 } else {
1057 if (!access_ok(VERIFY_WRITE, addr, 8 * rvar))
1058 goto sigbus;
1059 }
1060 if (rvar == 9)
1061 rvar = 8;
1062
1063 for (i = 16; rvar; rvar--, i++) {
1064 value = regs->regs[i];
1065 StoreDW(addr, value, res);
1066 if (res)
1067 goto fault;
1068 addr += 8;
1069 }
1070 if ((reg & 0xf) == 9) {
1071 value = regs->regs[30];
1072 StoreDW(addr, value, res);
1073 if (res)
1074 goto fault;
1075 addr += 8;
1076 }
1077 if (reg & 0x10) {
1078 value = regs->regs[31];
1079 StoreDW(addr, value, res);
1080 if (res)
1081 goto fault;
1082 }
1083 goto success;
1084#endif /* CONFIG_64BIT */
1085
1086 goto sigill;
1087
1088 /* LWC2, SWC2, LDC2, SDC2 are not serviced */
1089 }
1090
1091 goto sigbus;
1092
1093 case mm_pool32c_op:
1094 switch (insn.mm_m_format.func) {
1095 case mm_lwu_func:
1096 reg = insn.mm_m_format.rd;
1097 goto loadWU;
1098 }
1099
1100 /* LL,SC,LLD,SCD are not serviced */
1101 goto sigbus;
1102
1103 case mm_pool32f_op:
1104 switch (insn.mm_x_format.func) {
1105 case mm_lwxc1_func:
1106 case mm_swxc1_func:
1107 case mm_ldxc1_func:
1108 case mm_sdxc1_func:
1109 goto fpu_emul;
1110 }
1111
1112 goto sigbus;
1113
1114 case mm_ldc132_op:
1115 case mm_sdc132_op:
1116 case mm_lwc132_op:
1117 case mm_swc132_op:
1118fpu_emul:
1119 /* roll back jump/branch */
1120 regs->cp0_epc = origpc;
1121 regs->regs[31] = orig31;
1122
1123 die_if_kernel("Unaligned FP access in kernel code", regs);
1124 BUG_ON(!used_math());
1125 BUG_ON(!is_fpu_owner());
1126
1127 lose_fpu(1); /* save the FPU state for the emulator */
1128 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
1129 &fault_addr);
1130 own_fpu(1); /* restore FPU state */
1131
1132 /* If something went wrong, signal */
1133 process_fpemu_return(res, fault_addr);
1134
1135 if (res == 0)
1136 goto success;
1137 return;
1138
1139 case mm_lh32_op:
1140 reg = insn.mm_i_format.rt;
1141 goto loadHW;
1142
1143 case mm_lhu32_op:
1144 reg = insn.mm_i_format.rt;
1145 goto loadHWU;
1146
1147 case mm_lw32_op:
1148 reg = insn.mm_i_format.rt;
1149 goto loadW;
1150
1151 case mm_sh32_op:
1152 reg = insn.mm_i_format.rt;
1153 goto storeHW;
1154
1155 case mm_sw32_op:
1156 reg = insn.mm_i_format.rt;
1157 goto storeW;
1158
1159 case mm_ld32_op:
1160 reg = insn.mm_i_format.rt;
1161 goto loadDW;
1162
1163 case mm_sd32_op:
1164 reg = insn.mm_i_format.rt;
1165 goto storeDW;
1166
1167 case mm_pool16c_op:
1168 switch (insn.mm16_m_format.func) {
1169 case mm_lwm16_op:
1170 reg = insn.mm16_m_format.rlist;
1171 rvar = reg + 1;
1172 if (!access_ok(VERIFY_READ, addr, 4 * rvar))
1173 goto sigbus;
1174
1175 for (i = 16; rvar; rvar--, i++) {
1176 LoadW(addr, value, res);
1177 if (res)
1178 goto fault;
1179 addr += 4;
1180 regs->regs[i] = value;
1181 }
1182 LoadW(addr, value, res);
1183 if (res)
1184 goto fault;
1185 regs->regs[31] = value;
1186
1187 goto success;
1188
1189 case mm_swm16_op:
1190 reg = insn.mm16_m_format.rlist;
1191 rvar = reg + 1;
1192 if (!access_ok(VERIFY_WRITE, addr, 4 * rvar))
1193 goto sigbus;
1194
1195 for (i = 16; rvar; rvar--, i++) {
1196 value = regs->regs[i];
1197 StoreW(addr, value, res);
1198 if (res)
1199 goto fault;
1200 addr += 4;
1201 }
1202 value = regs->regs[31];
1203 StoreW(addr, value, res);
1204 if (res)
1205 goto fault;
1206
1207 goto success;
1208
1209 }
1210
1211 goto sigbus;
1212
1213 case mm_lhu16_op:
1214 reg = reg16to32[insn.mm16_rb_format.rt];
1215 goto loadHWU;
1216
1217 case mm_lw16_op:
1218 reg = reg16to32[insn.mm16_rb_format.rt];
1219 goto loadW;
1220
1221 case mm_sh16_op:
1222 reg = reg16to32st[insn.mm16_rb_format.rt];
1223 goto storeHW;
1224
1225 case mm_sw16_op:
1226 reg = reg16to32st[insn.mm16_rb_format.rt];
1227 goto storeW;
1228
1229 case mm_lwsp16_op:
1230 reg = insn.mm16_r5_format.rt;
1231 goto loadW;
1232
1233 case mm_swsp16_op:
1234 reg = insn.mm16_r5_format.rt;
1235 goto storeW;
1236
1237 case mm_lwgp16_op:
1238 reg = reg16to32[insn.mm16_r3_format.rt];
1239 goto loadW;
1240
1241 default:
1242 goto sigill;
1243 }
1244
1245loadHW:
1246 if (!access_ok(VERIFY_READ, addr, 2))
1247 goto sigbus;
1248
1249 LoadHW(addr, value, res);
1250 if (res)
1251 goto fault;
1252 regs->regs[reg] = value;
1253 goto success;
1254
1255loadHWU:
1256 if (!access_ok(VERIFY_READ, addr, 2))
1257 goto sigbus;
1258
1259 LoadHWU(addr, value, res);
1260 if (res)
1261 goto fault;
1262 regs->regs[reg] = value;
1263 goto success;
1264
1265loadW:
1266 if (!access_ok(VERIFY_READ, addr, 4))
1267 goto sigbus;
1268
1269 LoadW(addr, value, res);
1270 if (res)
1271 goto fault;
1272 regs->regs[reg] = value;
1273 goto success;
1274
1275loadWU:
1276#ifdef CONFIG_64BIT
1277 /*
1278 * A 32-bit kernel might be running on a 64-bit processor. But
1279 * if we're on a 32-bit processor and an i-cache incoherency
1280 * or race makes us see a 64-bit instruction here the sdl/sdr
1281 * would blow up, so for now we don't handle unaligned 64-bit
1282 * instructions on 32-bit kernels.
1283 */
1284 if (!access_ok(VERIFY_READ, addr, 4))
1285 goto sigbus;
1286
1287 LoadWU(addr, value, res);
1288 if (res)
1289 goto fault;
1290 regs->regs[reg] = value;
1291 goto success;
1292#endif /* CONFIG_64BIT */
1293
1294 /* Cannot handle 64-bit instructions in 32-bit kernel */
1295 goto sigill;
1296
1297loadDW:
1298#ifdef CONFIG_64BIT
1299 /*
1300 * A 32-bit kernel might be running on a 64-bit processor. But
1301 * if we're on a 32-bit processor and an i-cache incoherency
1302 * or race makes us see a 64-bit instruction here the sdl/sdr
1303 * would blow up, so for now we don't handle unaligned 64-bit
1304 * instructions on 32-bit kernels.
1305 */
1306 if (!access_ok(VERIFY_READ, addr, 8))
1307 goto sigbus;
1308
1309 LoadDW(addr, value, res);
1310 if (res)
1311 goto fault;
1312 regs->regs[reg] = value;
1313 goto success;
1314#endif /* CONFIG_64BIT */
1315
1316 /* Cannot handle 64-bit instructions in 32-bit kernel */
1317 goto sigill;
1318
1319storeHW:
1320 if (!access_ok(VERIFY_WRITE, addr, 2))
1321 goto sigbus;
1322
1323 value = regs->regs[reg];
1324 StoreHW(addr, value, res);
1325 if (res)
1326 goto fault;
1327 goto success;
1328
1329storeW:
1330 if (!access_ok(VERIFY_WRITE, addr, 4))
1331 goto sigbus;
1332
1333 value = regs->regs[reg];
1334 StoreW(addr, value, res);
1335 if (res)
1336 goto fault;
1337 goto success;
1338
1339storeDW:
1340#ifdef CONFIG_64BIT
1341 /*
1342 * A 32-bit kernel might be running on a 64-bit processor. But
1343 * if we're on a 32-bit processor and an i-cache incoherency
1344 * or race makes us see a 64-bit instruction here the sdl/sdr
1345 * would blow up, so for now we don't handle unaligned 64-bit
1346 * instructions on 32-bit kernels.
1347 */
1348 if (!access_ok(VERIFY_WRITE, addr, 8))
1349 goto sigbus;
1350
1351 value = regs->regs[reg];
1352 StoreDW(addr, value, res);
1353 if (res)
1354 goto fault;
1355 goto success;
1356#endif /* CONFIG_64BIT */
1357
1358 /* Cannot handle 64-bit instructions in 32-bit kernel */
1359 goto sigill;
1360
1361success:
1362 regs->cp0_epc = contpc; /* advance or branch */
1363
1364#ifdef CONFIG_DEBUG_FS
1365 unaligned_instructions++;
1366#endif
1367 return;
1368
1369fault:
1370 /* roll back jump/branch */
1371 regs->cp0_epc = origpc;
1372 regs->regs[31] = orig31;
1373 /* Did we have an exception handler installed? */
1374 if (fixup_exception(regs))
1375 return;
1376
1377 die_if_kernel("Unhandled kernel unaligned access", regs);
1378 force_sig(SIGSEGV, current);
1379
1380 return;
1381
1382sigbus:
1383 die_if_kernel("Unhandled kernel unaligned access", regs);
1384 force_sig(SIGBUS, current);
1385
1386 return;
1387
1388sigill:
1389 die_if_kernel
1390 ("Unhandled kernel unaligned access or invalid instruction", regs);
1391 force_sig(SIGILL, current);
1392}
1393
1394static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
1395{
1396 unsigned long value;
1397 unsigned int res;
1398 int reg;
1399 unsigned long orig31;
1400 u16 __user *pc16;
1401 unsigned long origpc;
1402 union mips16e_instruction mips16inst, oldinst;
1403
1404 origpc = regs->cp0_epc;
1405 orig31 = regs->regs[31];
1406 pc16 = (unsigned short __user *)msk_isa16_mode(origpc);
1407 /*
1408 * This load never faults.
1409 */
1410 __get_user(mips16inst.full, pc16);
1411 oldinst = mips16inst;
1412
1413 /* skip EXTEND instruction */
1414 if (mips16inst.ri.opcode == MIPS16e_extend_op) {
1415 pc16++;
1416 __get_user(mips16inst.full, pc16);
1417 } else if (delay_slot(regs)) {
1418 /* skip jump instructions */
1419 /* JAL/JALX are 32 bits but have OPCODE in first short int */
1420 if (mips16inst.ri.opcode == MIPS16e_jal_op)
1421 pc16++;
1422 pc16++;
1423 if (get_user(mips16inst.full, pc16))
1424 goto sigbus;
1425 }
1426
1427 switch (mips16inst.ri.opcode) {
1428 case MIPS16e_i64_op: /* I64 or RI64 instruction */
1429 switch (mips16inst.i64.func) { /* I64/RI64 func field check */
1430 case MIPS16e_ldpc_func:
1431 case MIPS16e_ldsp_func:
1432 reg = reg16to32[mips16inst.ri64.ry];
1433 goto loadDW;
1434
1435 case MIPS16e_sdsp_func:
1436 reg = reg16to32[mips16inst.ri64.ry];
1437 goto writeDW;
1438
1439 case MIPS16e_sdrasp_func:
1440 reg = 29; /* GPRSP */
1441 goto writeDW;
1442 }
1443
1444 goto sigbus;
1445
1446 case MIPS16e_swsp_op:
1447 case MIPS16e_lwpc_op:
1448 case MIPS16e_lwsp_op:
1449 reg = reg16to32[mips16inst.ri.rx];
1450 break;
1451
1452 case MIPS16e_i8_op:
1453 if (mips16inst.i8.func != MIPS16e_swrasp_func)
1454 goto sigbus;
1455 reg = 29; /* GPRSP */
1456 break;
1457
1458 default:
1459 reg = reg16to32[mips16inst.rri.ry];
1460 break;
1461 }
1462
1463 switch (mips16inst.ri.opcode) {
1464
1465 case MIPS16e_lb_op:
1466 case MIPS16e_lbu_op:
1467 case MIPS16e_sb_op:
1468 goto sigbus;
1469
1470 case MIPS16e_lh_op:
1471 if (!access_ok(VERIFY_READ, addr, 2))
1472 goto sigbus;
1473
1474 LoadHW(addr, value, res);
1475 if (res)
1476 goto fault;
1477 MIPS16e_compute_return_epc(regs, &oldinst);
1478 regs->regs[reg] = value;
1479 break;
1480
1481 case MIPS16e_lhu_op:
1482 if (!access_ok(VERIFY_READ, addr, 2))
1483 goto sigbus;
1484
1485 LoadHWU(addr, value, res);
1486 if (res)
1487 goto fault;
1488 MIPS16e_compute_return_epc(regs, &oldinst);
1489 regs->regs[reg] = value;
1490 break;
1491
1492 case MIPS16e_lw_op:
1493 case MIPS16e_lwpc_op:
1494 case MIPS16e_lwsp_op:
1495 if (!access_ok(VERIFY_READ, addr, 4))
1496 goto sigbus;
1497
1498 LoadW(addr, value, res);
1499 if (res)
1500 goto fault;
1501 MIPS16e_compute_return_epc(regs, &oldinst);
1502 regs->regs[reg] = value;
1503 break;
1504
1505 case MIPS16e_lwu_op:
1506#ifdef CONFIG_64BIT
1507 /*
1508 * A 32-bit kernel might be running on a 64-bit processor. But
1509 * if we're on a 32-bit processor and an i-cache incoherency
1510 * or race makes us see a 64-bit instruction here the sdl/sdr
1511 * would blow up, so for now we don't handle unaligned 64-bit
1512 * instructions on 32-bit kernels.
1513 */
1514 if (!access_ok(VERIFY_READ, addr, 4))
1515 goto sigbus;
1516
1517 LoadWU(addr, value, res);
1518 if (res)
1519 goto fault;
1520 MIPS16e_compute_return_epc(regs, &oldinst);
1521 regs->regs[reg] = value;
1522 break;
1523#endif /* CONFIG_64BIT */
1524
1525 /* Cannot handle 64-bit instructions in 32-bit kernel */
1526 goto sigill;
1527
1528 case MIPS16e_ld_op:
1529loadDW:
1530#ifdef CONFIG_64BIT
1531 /*
1532 * A 32-bit kernel might be running on a 64-bit processor. But
1533 * if we're on a 32-bit processor and an i-cache incoherency
1534 * or race makes us see a 64-bit instruction here the sdl/sdr
1535 * would blow up, so for now we don't handle unaligned 64-bit
1536 * instructions on 32-bit kernels.
1537 */
1538 if (!access_ok(VERIFY_READ, addr, 8))
1539 goto sigbus;
1540
1541 LoadDW(addr, value, res);
1542 if (res)
1543 goto fault;
1544 MIPS16e_compute_return_epc(regs, &oldinst);
1545 regs->regs[reg] = value;
1546 break;
1547#endif /* CONFIG_64BIT */
1548
1549 /* Cannot handle 64-bit instructions in 32-bit kernel */
1550 goto sigill;
1551
1552 case MIPS16e_sh_op:
1553 if (!access_ok(VERIFY_WRITE, addr, 2))
1554 goto sigbus;
1555
1556 MIPS16e_compute_return_epc(regs, &oldinst);
1557 value = regs->regs[reg];
1558 StoreHW(addr, value, res);
1559 if (res)
1560 goto fault;
1561 break;
1562
1563 case MIPS16e_sw_op:
1564 case MIPS16e_swsp_op:
1565 case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */
1566 if (!access_ok(VERIFY_WRITE, addr, 4))
1567 goto sigbus;
1568
1569 MIPS16e_compute_return_epc(regs, &oldinst);
1570 value = regs->regs[reg];
1571 StoreW(addr, value, res);
1572 if (res)
1573 goto fault;
1574 break;
1575
1576 case MIPS16e_sd_op:
1577writeDW:
1578#ifdef CONFIG_64BIT
1579 /*
1580 * A 32-bit kernel might be running on a 64-bit processor. But
1581 * if we're on a 32-bit processor and an i-cache incoherency
1582 * or race makes us see a 64-bit instruction here the sdl/sdr
1583 * would blow up, so for now we don't handle unaligned 64-bit
1584 * instructions on 32-bit kernels.
1585 */
1586 if (!access_ok(VERIFY_WRITE, addr, 8))
1587 goto sigbus;
1588
1589 MIPS16e_compute_return_epc(regs, &oldinst);
1590 value = regs->regs[reg];
1591 StoreDW(addr, value, res);
1592 if (res)
1593 goto fault;
1594 break;
1595#endif /* CONFIG_64BIT */
1596
1597 /* Cannot handle 64-bit instructions in 32-bit kernel */
1598 goto sigill;
1599
1600 default:
1601 /*
1602 * Pheeee... We encountered an yet unknown instruction or
1603 * cache coherence problem. Die sucker, die ...
1604 */
1605 goto sigill;
1606 }
1607
1608#ifdef CONFIG_DEBUG_FS
1609 unaligned_instructions++;
1610#endif
1611
1612 return;
1613
1614fault:
1615 /* roll back jump/branch */
1616 regs->cp0_epc = origpc;
1617 regs->regs[31] = orig31;
1618 /* Did we have an exception handler installed? */
1619 if (fixup_exception(regs))
1620 return;
1621
1622 die_if_kernel("Unhandled kernel unaligned access", regs);
1623 force_sig(SIGSEGV, current);
1624
1625 return;
1626
1627sigbus:
1628 die_if_kernel("Unhandled kernel unaligned access", regs);
1629 force_sig(SIGBUS, current);
1630
1631 return;
1632
1633sigill:
1634 die_if_kernel
1635 ("Unhandled kernel unaligned access or invalid instruction", regs);
1636 force_sig(SIGILL, current);
1637}
1638
1639asmlinkage void do_ade(struct pt_regs *regs)
1640{
1641 enum ctx_state prev_state;
1642 unsigned int __user *pc;
1643 mm_segment_t seg;
1644
1645 prev_state = exception_enter();
1646 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS,
1647 1, regs, regs->cp0_badvaddr);
1648 /*
1649 * Did we catch a fault trying to load an instruction?
1650 */
1651 if (regs->cp0_badvaddr == regs->cp0_epc)
1652 goto sigbus;
1653
1654 if (user_mode(regs) && !test_thread_flag(TIF_FIXADE))
1655 goto sigbus;
1656 if (unaligned_action == UNALIGNED_ACTION_SIGNAL)
1657 goto sigbus;
1658
1659 /*
1660 * Do branch emulation only if we didn't forward the exception.
1661 * This is all so but ugly ...
1662 */
1663
1664 /*
1665 * Are we running in microMIPS mode?
1666 */
1667 if (get_isa16_mode(regs->cp0_epc)) {
1668 /*
1669 * Did we catch a fault trying to load an instruction in
1670 * 16-bit mode?
1671 */
1672 if (regs->cp0_badvaddr == msk_isa16_mode(regs->cp0_epc))
1673 goto sigbus;
1674 if (unaligned_action == UNALIGNED_ACTION_SHOW)
1675 show_registers(regs);
1676
1677 if (cpu_has_mmips) {
1678 seg = get_fs();
1679 if (!user_mode(regs))
1680 set_fs(KERNEL_DS);
1681 emulate_load_store_microMIPS(regs,
1682 (void __user *)regs->cp0_badvaddr);
1683 set_fs(seg);
1684
1685 return;
1686 }
1687
1688 if (cpu_has_mips16) {
1689 seg = get_fs();
1690 if (!user_mode(regs))
1691 set_fs(KERNEL_DS);
1692 emulate_load_store_MIPS16e(regs,
1693 (void __user *)regs->cp0_badvaddr);
1694 set_fs(seg);
1695
1696 return;
1697 }
1698
1699 goto sigbus;
1700 }
1701
1702 if (unaligned_action == UNALIGNED_ACTION_SHOW)
1703 show_registers(regs);
1704 pc = (unsigned int __user *)exception_epc(regs);
1705
1706 seg = get_fs();
1707 if (!user_mode(regs))
1708 set_fs(KERNEL_DS);
1709 emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc);
1710 set_fs(seg);
1711
1712 return;
1713
1714sigbus:
1715 die_if_kernel("Kernel unaligned instruction access", regs);
1716 force_sig(SIGBUS, current);
1717
1718 /*
1719 * XXX On return from the signal handler we should advance the epc
1720 */
1721 exception_exit(prev_state);
1722}
1723
1724#ifdef CONFIG_DEBUG_FS
1725extern struct dentry *mips_debugfs_dir;
1726static int __init debugfs_unaligned(void)
1727{
1728 struct dentry *d;
1729
1730 if (!mips_debugfs_dir)
1731 return -ENODEV;
1732 d = debugfs_create_u32("unaligned_instructions", S_IRUGO,
1733 mips_debugfs_dir, &unaligned_instructions);
1734 if (!d)
1735 return -ENOMEM;
1736 d = debugfs_create_u32("unaligned_action", S_IRUGO | S_IWUSR,
1737 mips_debugfs_dir, &unaligned_action);
1738 if (!d)
1739 return -ENOMEM;
1740 return 0;
1741}
1742__initcall(debugfs_unaligned);
1743#endif