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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/unaligned-emul.h>
93#include <asm/mmu_context.h>
94#include <linux/uaccess.h>
95
96#include "access-helper.h"
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
111static void emulate_load_store_insn(struct pt_regs *regs,
112 void __user *addr, unsigned int *pc)
113{
114 unsigned long origpc, orig31, value;
115 union mips_instruction insn;
116 unsigned int res;
117 bool user = user_mode(regs);
118
119 origpc = (unsigned long)pc;
120 orig31 = regs->regs[31];
121
122 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
123
124 /*
125 * This load never faults.
126 */
127 __get_inst32(&insn.word, pc, user);
128
129 switch (insn.i_format.opcode) {
130 /*
131 * These are instructions that a compiler doesn't generate. We
132 * can assume therefore that the code is MIPS-aware and
133 * really buggy. Emulating these instructions would break the
134 * semantics anyway.
135 */
136 case ll_op:
137 case lld_op:
138 case sc_op:
139 case scd_op:
140
141 /*
142 * For these instructions the only way to create an address
143 * error is an attempted access to kernel/supervisor address
144 * space.
145 */
146 case ldl_op:
147 case ldr_op:
148 case lwl_op:
149 case lwr_op:
150 case sdl_op:
151 case sdr_op:
152 case swl_op:
153 case swr_op:
154 case lb_op:
155 case lbu_op:
156 case sb_op:
157 goto sigbus;
158
159 /*
160 * The remaining opcodes are the ones that are really of
161 * interest.
162 */
163 case spec3_op:
164 if (insn.dsp_format.func == lx_op) {
165 switch (insn.dsp_format.op) {
166 case lwx_op:
167 if (user && !access_ok(addr, 4))
168 goto sigbus;
169 LoadW(addr, value, res);
170 if (res)
171 goto fault;
172 compute_return_epc(regs);
173 regs->regs[insn.dsp_format.rd] = value;
174 break;
175 case lhx_op:
176 if (user && !access_ok(addr, 2))
177 goto sigbus;
178 LoadHW(addr, value, res);
179 if (res)
180 goto fault;
181 compute_return_epc(regs);
182 regs->regs[insn.dsp_format.rd] = value;
183 break;
184 default:
185 goto sigill;
186 }
187 }
188#ifdef CONFIG_EVA
189 else {
190 /*
191 * we can land here only from kernel accessing user
192 * memory, so we need to "switch" the address limit to
193 * user space, so that address check can work properly.
194 */
195 switch (insn.spec3_format.func) {
196 case lhe_op:
197 if (!access_ok(addr, 2))
198 goto sigbus;
199 LoadHWE(addr, value, res);
200 if (res)
201 goto fault;
202 compute_return_epc(regs);
203 regs->regs[insn.spec3_format.rt] = value;
204 break;
205 case lwe_op:
206 if (!access_ok(addr, 4))
207 goto sigbus;
208 LoadWE(addr, value, res);
209 if (res)
210 goto fault;
211 compute_return_epc(regs);
212 regs->regs[insn.spec3_format.rt] = value;
213 break;
214 case lhue_op:
215 if (!access_ok(addr, 2))
216 goto sigbus;
217 LoadHWUE(addr, value, res);
218 if (res)
219 goto fault;
220 compute_return_epc(regs);
221 regs->regs[insn.spec3_format.rt] = value;
222 break;
223 case she_op:
224 if (!access_ok(addr, 2))
225 goto sigbus;
226 compute_return_epc(regs);
227 value = regs->regs[insn.spec3_format.rt];
228 StoreHWE(addr, value, res);
229 if (res)
230 goto fault;
231 break;
232 case swe_op:
233 if (!access_ok(addr, 4))
234 goto sigbus;
235 compute_return_epc(regs);
236 value = regs->regs[insn.spec3_format.rt];
237 StoreWE(addr, value, res);
238 if (res)
239 goto fault;
240 break;
241 default:
242 goto sigill;
243 }
244 }
245#endif
246 break;
247 case lh_op:
248 if (user && !access_ok(addr, 2))
249 goto sigbus;
250
251 if (IS_ENABLED(CONFIG_EVA) && user)
252 LoadHWE(addr, value, res);
253 else
254 LoadHW(addr, value, res);
255
256 if (res)
257 goto fault;
258 compute_return_epc(regs);
259 regs->regs[insn.i_format.rt] = value;
260 break;
261
262 case lw_op:
263 if (user && !access_ok(addr, 4))
264 goto sigbus;
265
266 if (IS_ENABLED(CONFIG_EVA) && user)
267 LoadWE(addr, value, res);
268 else
269 LoadW(addr, value, res);
270
271 if (res)
272 goto fault;
273 compute_return_epc(regs);
274 regs->regs[insn.i_format.rt] = value;
275 break;
276
277 case lhu_op:
278 if (user && !access_ok(addr, 2))
279 goto sigbus;
280
281 if (IS_ENABLED(CONFIG_EVA) && user)
282 LoadHWUE(addr, value, res);
283 else
284 LoadHWU(addr, value, res);
285
286 if (res)
287 goto fault;
288 compute_return_epc(regs);
289 regs->regs[insn.i_format.rt] = value;
290 break;
291
292 case lwu_op:
293#ifdef CONFIG_64BIT
294 /*
295 * A 32-bit kernel might be running on a 64-bit processor. But
296 * if we're on a 32-bit processor and an i-cache incoherency
297 * or race makes us see a 64-bit instruction here the sdl/sdr
298 * would blow up, so for now we don't handle unaligned 64-bit
299 * instructions on 32-bit kernels.
300 */
301 if (user && !access_ok(addr, 4))
302 goto sigbus;
303
304 LoadWU(addr, value, res);
305 if (res)
306 goto fault;
307 compute_return_epc(regs);
308 regs->regs[insn.i_format.rt] = value;
309 break;
310#endif /* CONFIG_64BIT */
311
312 /* Cannot handle 64-bit instructions in 32-bit kernel */
313 goto sigill;
314
315 case ld_op:
316#ifdef CONFIG_64BIT
317 /*
318 * A 32-bit kernel might be running on a 64-bit processor. But
319 * if we're on a 32-bit processor and an i-cache incoherency
320 * or race makes us see a 64-bit instruction here the sdl/sdr
321 * would blow up, so for now we don't handle unaligned 64-bit
322 * instructions on 32-bit kernels.
323 */
324 if (user && !access_ok(addr, 8))
325 goto sigbus;
326
327 LoadDW(addr, value, res);
328 if (res)
329 goto fault;
330 compute_return_epc(regs);
331 regs->regs[insn.i_format.rt] = value;
332 break;
333#endif /* CONFIG_64BIT */
334
335 /* Cannot handle 64-bit instructions in 32-bit kernel */
336 goto sigill;
337
338 case sh_op:
339 if (user && !access_ok(addr, 2))
340 goto sigbus;
341
342 compute_return_epc(regs);
343 value = regs->regs[insn.i_format.rt];
344
345 if (IS_ENABLED(CONFIG_EVA) && user)
346 StoreHWE(addr, value, res);
347 else
348 StoreHW(addr, value, res);
349
350 if (res)
351 goto fault;
352 break;
353
354 case sw_op:
355 if (user && !access_ok(addr, 4))
356 goto sigbus;
357
358 compute_return_epc(regs);
359 value = regs->regs[insn.i_format.rt];
360
361 if (IS_ENABLED(CONFIG_EVA) && user)
362 StoreWE(addr, value, res);
363 else
364 StoreW(addr, value, res);
365
366 if (res)
367 goto fault;
368 break;
369
370 case sd_op:
371#ifdef CONFIG_64BIT
372 /*
373 * A 32-bit kernel might be running on a 64-bit processor. But
374 * if we're on a 32-bit processor and an i-cache incoherency
375 * or race makes us see a 64-bit instruction here the sdl/sdr
376 * would blow up, so for now we don't handle unaligned 64-bit
377 * instructions on 32-bit kernels.
378 */
379 if (user && !access_ok(addr, 8))
380 goto sigbus;
381
382 compute_return_epc(regs);
383 value = regs->regs[insn.i_format.rt];
384 StoreDW(addr, value, res);
385 if (res)
386 goto fault;
387 break;
388#endif /* CONFIG_64BIT */
389
390 /* Cannot handle 64-bit instructions in 32-bit kernel */
391 goto sigill;
392
393#ifdef CONFIG_MIPS_FP_SUPPORT
394
395 case lwc1_op:
396 case ldc1_op:
397 case swc1_op:
398 case sdc1_op:
399 case cop1x_op: {
400 void __user *fault_addr = NULL;
401
402 die_if_kernel("Unaligned FP access in kernel code", regs);
403 BUG_ON(!used_math());
404
405 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
406 &fault_addr);
407 own_fpu(1); /* Restore FPU state. */
408
409 /* Signal if something went wrong. */
410 process_fpemu_return(res, fault_addr, 0);
411
412 if (res == 0)
413 break;
414 return;
415 }
416#endif /* CONFIG_MIPS_FP_SUPPORT */
417
418#ifdef CONFIG_CPU_HAS_MSA
419
420 case msa_op: {
421 unsigned int wd, preempted;
422 enum msa_2b_fmt df;
423 union fpureg *fpr;
424
425 if (!cpu_has_msa)
426 goto sigill;
427
428 /*
429 * If we've reached this point then userland should have taken
430 * the MSA disabled exception & initialised vector context at
431 * some point in the past.
432 */
433 BUG_ON(!thread_msa_context_live());
434
435 df = insn.msa_mi10_format.df;
436 wd = insn.msa_mi10_format.wd;
437 fpr = ¤t->thread.fpu.fpr[wd];
438
439 switch (insn.msa_mi10_format.func) {
440 case msa_ld_op:
441 if (!access_ok(addr, sizeof(*fpr)))
442 goto sigbus;
443
444 do {
445 /*
446 * If we have live MSA context keep track of
447 * whether we get preempted in order to avoid
448 * the register context we load being clobbered
449 * by the live context as it's saved during
450 * preemption. If we don't have live context
451 * then it can't be saved to clobber the value
452 * we load.
453 */
454 preempted = test_thread_flag(TIF_USEDMSA);
455
456 res = __copy_from_user_inatomic(fpr, addr,
457 sizeof(*fpr));
458 if (res)
459 goto fault;
460
461 /*
462 * Update the hardware register if it is in use
463 * by the task in this quantum, in order to
464 * avoid having to save & restore the whole
465 * vector context.
466 */
467 preempt_disable();
468 if (test_thread_flag(TIF_USEDMSA)) {
469 write_msa_wr(wd, fpr, df);
470 preempted = 0;
471 }
472 preempt_enable();
473 } while (preempted);
474 break;
475
476 case msa_st_op:
477 if (!access_ok(addr, sizeof(*fpr)))
478 goto sigbus;
479
480 /*
481 * Update from the hardware register if it is in use by
482 * the task in this quantum, in order to avoid having to
483 * save & restore the whole vector context.
484 */
485 preempt_disable();
486 if (test_thread_flag(TIF_USEDMSA))
487 read_msa_wr(wd, fpr, df);
488 preempt_enable();
489
490 res = __copy_to_user_inatomic(addr, fpr, sizeof(*fpr));
491 if (res)
492 goto fault;
493 break;
494
495 default:
496 goto sigbus;
497 }
498
499 compute_return_epc(regs);
500 break;
501 }
502#endif /* CONFIG_CPU_HAS_MSA */
503
504#ifndef CONFIG_CPU_MIPSR6
505 /*
506 * COP2 is available to implementor for application specific use.
507 * It's up to applications to register a notifier chain and do
508 * whatever they have to do, including possible sending of signals.
509 *
510 * This instruction has been reallocated in Release 6
511 */
512 case lwc2_op:
513 cu2_notifier_call_chain(CU2_LWC2_OP, regs);
514 break;
515
516 case ldc2_op:
517 cu2_notifier_call_chain(CU2_LDC2_OP, regs);
518 break;
519
520 case swc2_op:
521 cu2_notifier_call_chain(CU2_SWC2_OP, regs);
522 break;
523
524 case sdc2_op:
525 cu2_notifier_call_chain(CU2_SDC2_OP, regs);
526 break;
527#endif
528 default:
529 /*
530 * Pheeee... We encountered an yet unknown instruction or
531 * cache coherence problem. Die sucker, die ...
532 */
533 goto sigill;
534 }
535
536#ifdef CONFIG_DEBUG_FS
537 unaligned_instructions++;
538#endif
539
540 return;
541
542fault:
543 /* roll back jump/branch */
544 regs->cp0_epc = origpc;
545 regs->regs[31] = orig31;
546 /* Did we have an exception handler installed? */
547 if (fixup_exception(regs))
548 return;
549
550 die_if_kernel("Unhandled kernel unaligned access", regs);
551 force_sig(SIGSEGV);
552
553 return;
554
555sigbus:
556 die_if_kernel("Unhandled kernel unaligned access", regs);
557 force_sig(SIGBUS);
558
559 return;
560
561sigill:
562 die_if_kernel
563 ("Unhandled kernel unaligned access or invalid instruction", regs);
564 force_sig(SIGILL);
565}
566
567/* Recode table from 16-bit register notation to 32-bit GPR. */
568const int reg16to32[] = { 16, 17, 2, 3, 4, 5, 6, 7 };
569
570/* Recode table from 16-bit STORE register notation to 32-bit GPR. */
571static const int reg16to32st[] = { 0, 17, 2, 3, 4, 5, 6, 7 };
572
573static void emulate_load_store_microMIPS(struct pt_regs *regs,
574 void __user *addr)
575{
576 unsigned long value;
577 unsigned int res;
578 int i;
579 unsigned int reg = 0, rvar;
580 unsigned long orig31;
581 u16 __user *pc16;
582 u16 halfword;
583 unsigned int word;
584 unsigned long origpc, contpc;
585 union mips_instruction insn;
586 struct mm_decoded_insn mminsn;
587 bool user = user_mode(regs);
588
589 origpc = regs->cp0_epc;
590 orig31 = regs->regs[31];
591
592 mminsn.micro_mips_mode = 1;
593
594 /*
595 * This load never faults.
596 */
597 pc16 = (unsigned short __user *)msk_isa16_mode(regs->cp0_epc);
598 __get_user(halfword, pc16);
599 pc16++;
600 contpc = regs->cp0_epc + 2;
601 word = ((unsigned int)halfword << 16);
602 mminsn.pc_inc = 2;
603
604 if (!mm_insn_16bit(halfword)) {
605 __get_user(halfword, pc16);
606 pc16++;
607 contpc = regs->cp0_epc + 4;
608 mminsn.pc_inc = 4;
609 word |= halfword;
610 }
611 mminsn.insn = word;
612
613 if (get_user(halfword, pc16))
614 goto fault;
615 mminsn.next_pc_inc = 2;
616 word = ((unsigned int)halfword << 16);
617
618 if (!mm_insn_16bit(halfword)) {
619 pc16++;
620 if (get_user(halfword, pc16))
621 goto fault;
622 mminsn.next_pc_inc = 4;
623 word |= halfword;
624 }
625 mminsn.next_insn = word;
626
627 insn = (union mips_instruction)(mminsn.insn);
628 if (mm_isBranchInstr(regs, mminsn, &contpc))
629 insn = (union mips_instruction)(mminsn.next_insn);
630
631 /* Parse instruction to find what to do */
632
633 switch (insn.mm_i_format.opcode) {
634
635 case mm_pool32a_op:
636 switch (insn.mm_x_format.func) {
637 case mm_lwxs_op:
638 reg = insn.mm_x_format.rd;
639 goto loadW;
640 }
641
642 goto sigbus;
643
644 case mm_pool32b_op:
645 switch (insn.mm_m_format.func) {
646 case mm_lwp_func:
647 reg = insn.mm_m_format.rd;
648 if (reg == 31)
649 goto sigbus;
650
651 if (user && !access_ok(addr, 8))
652 goto sigbus;
653
654 LoadW(addr, value, res);
655 if (res)
656 goto fault;
657 regs->regs[reg] = value;
658 addr += 4;
659 LoadW(addr, value, res);
660 if (res)
661 goto fault;
662 regs->regs[reg + 1] = value;
663 goto success;
664
665 case mm_swp_func:
666 reg = insn.mm_m_format.rd;
667 if (reg == 31)
668 goto sigbus;
669
670 if (user && !access_ok(addr, 8))
671 goto sigbus;
672
673 value = regs->regs[reg];
674 StoreW(addr, value, res);
675 if (res)
676 goto fault;
677 addr += 4;
678 value = regs->regs[reg + 1];
679 StoreW(addr, value, res);
680 if (res)
681 goto fault;
682 goto success;
683
684 case mm_ldp_func:
685#ifdef CONFIG_64BIT
686 reg = insn.mm_m_format.rd;
687 if (reg == 31)
688 goto sigbus;
689
690 if (user && !access_ok(addr, 16))
691 goto sigbus;
692
693 LoadDW(addr, value, res);
694 if (res)
695 goto fault;
696 regs->regs[reg] = value;
697 addr += 8;
698 LoadDW(addr, value, res);
699 if (res)
700 goto fault;
701 regs->regs[reg + 1] = value;
702 goto success;
703#endif /* CONFIG_64BIT */
704
705 goto sigill;
706
707 case mm_sdp_func:
708#ifdef CONFIG_64BIT
709 reg = insn.mm_m_format.rd;
710 if (reg == 31)
711 goto sigbus;
712
713 if (user && !access_ok(addr, 16))
714 goto sigbus;
715
716 value = regs->regs[reg];
717 StoreDW(addr, value, res);
718 if (res)
719 goto fault;
720 addr += 8;
721 value = regs->regs[reg + 1];
722 StoreDW(addr, value, res);
723 if (res)
724 goto fault;
725 goto success;
726#endif /* CONFIG_64BIT */
727
728 goto sigill;
729
730 case mm_lwm32_func:
731 reg = insn.mm_m_format.rd;
732 rvar = reg & 0xf;
733 if ((rvar > 9) || !reg)
734 goto sigill;
735 if (reg & 0x10) {
736 if (user && !access_ok(addr, 4 * (rvar + 1)))
737 goto sigbus;
738 } else {
739 if (user && !access_ok(addr, 4 * rvar))
740 goto sigbus;
741 }
742 if (rvar == 9)
743 rvar = 8;
744 for (i = 16; rvar; rvar--, i++) {
745 LoadW(addr, value, res);
746 if (res)
747 goto fault;
748 addr += 4;
749 regs->regs[i] = value;
750 }
751 if ((reg & 0xf) == 9) {
752 LoadW(addr, value, res);
753 if (res)
754 goto fault;
755 addr += 4;
756 regs->regs[30] = value;
757 }
758 if (reg & 0x10) {
759 LoadW(addr, value, res);
760 if (res)
761 goto fault;
762 regs->regs[31] = value;
763 }
764 goto success;
765
766 case mm_swm32_func:
767 reg = insn.mm_m_format.rd;
768 rvar = reg & 0xf;
769 if ((rvar > 9) || !reg)
770 goto sigill;
771 if (reg & 0x10) {
772 if (user && !access_ok(addr, 4 * (rvar + 1)))
773 goto sigbus;
774 } else {
775 if (user && !access_ok(addr, 4 * rvar))
776 goto sigbus;
777 }
778 if (rvar == 9)
779 rvar = 8;
780 for (i = 16; rvar; rvar--, i++) {
781 value = regs->regs[i];
782 StoreW(addr, value, res);
783 if (res)
784 goto fault;
785 addr += 4;
786 }
787 if ((reg & 0xf) == 9) {
788 value = regs->regs[30];
789 StoreW(addr, value, res);
790 if (res)
791 goto fault;
792 addr += 4;
793 }
794 if (reg & 0x10) {
795 value = regs->regs[31];
796 StoreW(addr, value, res);
797 if (res)
798 goto fault;
799 }
800 goto success;
801
802 case mm_ldm_func:
803#ifdef CONFIG_64BIT
804 reg = insn.mm_m_format.rd;
805 rvar = reg & 0xf;
806 if ((rvar > 9) || !reg)
807 goto sigill;
808 if (reg & 0x10) {
809 if (user && !access_ok(addr, 8 * (rvar + 1)))
810 goto sigbus;
811 } else {
812 if (user && !access_ok(addr, 8 * rvar))
813 goto sigbus;
814 }
815 if (rvar == 9)
816 rvar = 8;
817
818 for (i = 16; rvar; rvar--, i++) {
819 LoadDW(addr, value, res);
820 if (res)
821 goto fault;
822 addr += 4;
823 regs->regs[i] = value;
824 }
825 if ((reg & 0xf) == 9) {
826 LoadDW(addr, value, res);
827 if (res)
828 goto fault;
829 addr += 8;
830 regs->regs[30] = value;
831 }
832 if (reg & 0x10) {
833 LoadDW(addr, value, res);
834 if (res)
835 goto fault;
836 regs->regs[31] = value;
837 }
838 goto success;
839#endif /* CONFIG_64BIT */
840
841 goto sigill;
842
843 case mm_sdm_func:
844#ifdef CONFIG_64BIT
845 reg = insn.mm_m_format.rd;
846 rvar = reg & 0xf;
847 if ((rvar > 9) || !reg)
848 goto sigill;
849 if (reg & 0x10) {
850 if (user && !access_ok(addr, 8 * (rvar + 1)))
851 goto sigbus;
852 } else {
853 if (user && !access_ok(addr, 8 * rvar))
854 goto sigbus;
855 }
856 if (rvar == 9)
857 rvar = 8;
858
859 for (i = 16; rvar; rvar--, i++) {
860 value = regs->regs[i];
861 StoreDW(addr, value, res);
862 if (res)
863 goto fault;
864 addr += 8;
865 }
866 if ((reg & 0xf) == 9) {
867 value = regs->regs[30];
868 StoreDW(addr, value, res);
869 if (res)
870 goto fault;
871 addr += 8;
872 }
873 if (reg & 0x10) {
874 value = regs->regs[31];
875 StoreDW(addr, value, res);
876 if (res)
877 goto fault;
878 }
879 goto success;
880#endif /* CONFIG_64BIT */
881
882 goto sigill;
883
884 /* LWC2, SWC2, LDC2, SDC2 are not serviced */
885 }
886
887 goto sigbus;
888
889 case mm_pool32c_op:
890 switch (insn.mm_m_format.func) {
891 case mm_lwu_func:
892 reg = insn.mm_m_format.rd;
893 goto loadWU;
894 }
895
896 /* LL,SC,LLD,SCD are not serviced */
897 goto sigbus;
898
899#ifdef CONFIG_MIPS_FP_SUPPORT
900 case mm_pool32f_op:
901 switch (insn.mm_x_format.func) {
902 case mm_lwxc1_func:
903 case mm_swxc1_func:
904 case mm_ldxc1_func:
905 case mm_sdxc1_func:
906 goto fpu_emul;
907 }
908
909 goto sigbus;
910
911 case mm_ldc132_op:
912 case mm_sdc132_op:
913 case mm_lwc132_op:
914 case mm_swc132_op: {
915 void __user *fault_addr = NULL;
916
917fpu_emul:
918 /* roll back jump/branch */
919 regs->cp0_epc = origpc;
920 regs->regs[31] = orig31;
921
922 die_if_kernel("Unaligned FP access in kernel code", regs);
923 BUG_ON(!used_math());
924 BUG_ON(!is_fpu_owner());
925
926 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
927 &fault_addr);
928 own_fpu(1); /* restore FPU state */
929
930 /* If something went wrong, signal */
931 process_fpemu_return(res, fault_addr, 0);
932
933 if (res == 0)
934 goto success;
935 return;
936 }
937#endif /* CONFIG_MIPS_FP_SUPPORT */
938
939 case mm_lh32_op:
940 reg = insn.mm_i_format.rt;
941 goto loadHW;
942
943 case mm_lhu32_op:
944 reg = insn.mm_i_format.rt;
945 goto loadHWU;
946
947 case mm_lw32_op:
948 reg = insn.mm_i_format.rt;
949 goto loadW;
950
951 case mm_sh32_op:
952 reg = insn.mm_i_format.rt;
953 goto storeHW;
954
955 case mm_sw32_op:
956 reg = insn.mm_i_format.rt;
957 goto storeW;
958
959 case mm_ld32_op:
960 reg = insn.mm_i_format.rt;
961 goto loadDW;
962
963 case mm_sd32_op:
964 reg = insn.mm_i_format.rt;
965 goto storeDW;
966
967 case mm_pool16c_op:
968 switch (insn.mm16_m_format.func) {
969 case mm_lwm16_op:
970 reg = insn.mm16_m_format.rlist;
971 rvar = reg + 1;
972 if (user && !access_ok(addr, 4 * rvar))
973 goto sigbus;
974
975 for (i = 16; rvar; rvar--, i++) {
976 LoadW(addr, value, res);
977 if (res)
978 goto fault;
979 addr += 4;
980 regs->regs[i] = value;
981 }
982 LoadW(addr, value, res);
983 if (res)
984 goto fault;
985 regs->regs[31] = value;
986
987 goto success;
988
989 case mm_swm16_op:
990 reg = insn.mm16_m_format.rlist;
991 rvar = reg + 1;
992 if (user && !access_ok(addr, 4 * rvar))
993 goto sigbus;
994
995 for (i = 16; rvar; rvar--, i++) {
996 value = regs->regs[i];
997 StoreW(addr, value, res);
998 if (res)
999 goto fault;
1000 addr += 4;
1001 }
1002 value = regs->regs[31];
1003 StoreW(addr, value, res);
1004 if (res)
1005 goto fault;
1006
1007 goto success;
1008
1009 }
1010
1011 goto sigbus;
1012
1013 case mm_lhu16_op:
1014 reg = reg16to32[insn.mm16_rb_format.rt];
1015 goto loadHWU;
1016
1017 case mm_lw16_op:
1018 reg = reg16to32[insn.mm16_rb_format.rt];
1019 goto loadW;
1020
1021 case mm_sh16_op:
1022 reg = reg16to32st[insn.mm16_rb_format.rt];
1023 goto storeHW;
1024
1025 case mm_sw16_op:
1026 reg = reg16to32st[insn.mm16_rb_format.rt];
1027 goto storeW;
1028
1029 case mm_lwsp16_op:
1030 reg = insn.mm16_r5_format.rt;
1031 goto loadW;
1032
1033 case mm_swsp16_op:
1034 reg = insn.mm16_r5_format.rt;
1035 goto storeW;
1036
1037 case mm_lwgp16_op:
1038 reg = reg16to32[insn.mm16_r3_format.rt];
1039 goto loadW;
1040
1041 default:
1042 goto sigill;
1043 }
1044
1045loadHW:
1046 if (user && !access_ok(addr, 2))
1047 goto sigbus;
1048
1049 LoadHW(addr, value, res);
1050 if (res)
1051 goto fault;
1052 regs->regs[reg] = value;
1053 goto success;
1054
1055loadHWU:
1056 if (user && !access_ok(addr, 2))
1057 goto sigbus;
1058
1059 LoadHWU(addr, value, res);
1060 if (res)
1061 goto fault;
1062 regs->regs[reg] = value;
1063 goto success;
1064
1065loadW:
1066 if (user && !access_ok(addr, 4))
1067 goto sigbus;
1068
1069 LoadW(addr, value, res);
1070 if (res)
1071 goto fault;
1072 regs->regs[reg] = value;
1073 goto success;
1074
1075loadWU:
1076#ifdef CONFIG_64BIT
1077 /*
1078 * A 32-bit kernel might be running on a 64-bit processor. But
1079 * if we're on a 32-bit processor and an i-cache incoherency
1080 * or race makes us see a 64-bit instruction here the sdl/sdr
1081 * would blow up, so for now we don't handle unaligned 64-bit
1082 * instructions on 32-bit kernels.
1083 */
1084 if (user && !access_ok(addr, 4))
1085 goto sigbus;
1086
1087 LoadWU(addr, value, res);
1088 if (res)
1089 goto fault;
1090 regs->regs[reg] = value;
1091 goto success;
1092#endif /* CONFIG_64BIT */
1093
1094 /* Cannot handle 64-bit instructions in 32-bit kernel */
1095 goto sigill;
1096
1097loadDW:
1098#ifdef CONFIG_64BIT
1099 /*
1100 * A 32-bit kernel might be running on a 64-bit processor. But
1101 * if we're on a 32-bit processor and an i-cache incoherency
1102 * or race makes us see a 64-bit instruction here the sdl/sdr
1103 * would blow up, so for now we don't handle unaligned 64-bit
1104 * instructions on 32-bit kernels.
1105 */
1106 if (user && !access_ok(addr, 8))
1107 goto sigbus;
1108
1109 LoadDW(addr, value, res);
1110 if (res)
1111 goto fault;
1112 regs->regs[reg] = value;
1113 goto success;
1114#endif /* CONFIG_64BIT */
1115
1116 /* Cannot handle 64-bit instructions in 32-bit kernel */
1117 goto sigill;
1118
1119storeHW:
1120 if (user && !access_ok(addr, 2))
1121 goto sigbus;
1122
1123 value = regs->regs[reg];
1124 StoreHW(addr, value, res);
1125 if (res)
1126 goto fault;
1127 goto success;
1128
1129storeW:
1130 if (user && !access_ok(addr, 4))
1131 goto sigbus;
1132
1133 value = regs->regs[reg];
1134 StoreW(addr, value, res);
1135 if (res)
1136 goto fault;
1137 goto success;
1138
1139storeDW:
1140#ifdef CONFIG_64BIT
1141 /*
1142 * A 32-bit kernel might be running on a 64-bit processor. But
1143 * if we're on a 32-bit processor and an i-cache incoherency
1144 * or race makes us see a 64-bit instruction here the sdl/sdr
1145 * would blow up, so for now we don't handle unaligned 64-bit
1146 * instructions on 32-bit kernels.
1147 */
1148 if (user && !access_ok(addr, 8))
1149 goto sigbus;
1150
1151 value = regs->regs[reg];
1152 StoreDW(addr, value, res);
1153 if (res)
1154 goto fault;
1155 goto success;
1156#endif /* CONFIG_64BIT */
1157
1158 /* Cannot handle 64-bit instructions in 32-bit kernel */
1159 goto sigill;
1160
1161success:
1162 regs->cp0_epc = contpc; /* advance or branch */
1163
1164#ifdef CONFIG_DEBUG_FS
1165 unaligned_instructions++;
1166#endif
1167 return;
1168
1169fault:
1170 /* roll back jump/branch */
1171 regs->cp0_epc = origpc;
1172 regs->regs[31] = orig31;
1173 /* Did we have an exception handler installed? */
1174 if (fixup_exception(regs))
1175 return;
1176
1177 die_if_kernel("Unhandled kernel unaligned access", regs);
1178 force_sig(SIGSEGV);
1179
1180 return;
1181
1182sigbus:
1183 die_if_kernel("Unhandled kernel unaligned access", regs);
1184 force_sig(SIGBUS);
1185
1186 return;
1187
1188sigill:
1189 die_if_kernel
1190 ("Unhandled kernel unaligned access or invalid instruction", regs);
1191 force_sig(SIGILL);
1192}
1193
1194static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
1195{
1196 unsigned long value;
1197 unsigned int res;
1198 int reg;
1199 unsigned long orig31;
1200 u16 __user *pc16;
1201 unsigned long origpc;
1202 union mips16e_instruction mips16inst, oldinst;
1203 unsigned int opcode;
1204 int extended = 0;
1205 bool user = user_mode(regs);
1206
1207 origpc = regs->cp0_epc;
1208 orig31 = regs->regs[31];
1209 pc16 = (unsigned short __user *)msk_isa16_mode(origpc);
1210 /*
1211 * This load never faults.
1212 */
1213 __get_user(mips16inst.full, pc16);
1214 oldinst = mips16inst;
1215
1216 /* skip EXTEND instruction */
1217 if (mips16inst.ri.opcode == MIPS16e_extend_op) {
1218 extended = 1;
1219 pc16++;
1220 __get_user(mips16inst.full, pc16);
1221 } else if (delay_slot(regs)) {
1222 /* skip jump instructions */
1223 /* JAL/JALX are 32 bits but have OPCODE in first short int */
1224 if (mips16inst.ri.opcode == MIPS16e_jal_op)
1225 pc16++;
1226 pc16++;
1227 if (get_user(mips16inst.full, pc16))
1228 goto sigbus;
1229 }
1230
1231 opcode = mips16inst.ri.opcode;
1232 switch (opcode) {
1233 case MIPS16e_i64_op: /* I64 or RI64 instruction */
1234 switch (mips16inst.i64.func) { /* I64/RI64 func field check */
1235 case MIPS16e_ldpc_func:
1236 case MIPS16e_ldsp_func:
1237 reg = reg16to32[mips16inst.ri64.ry];
1238 goto loadDW;
1239
1240 case MIPS16e_sdsp_func:
1241 reg = reg16to32[mips16inst.ri64.ry];
1242 goto writeDW;
1243
1244 case MIPS16e_sdrasp_func:
1245 reg = 29; /* GPRSP */
1246 goto writeDW;
1247 }
1248
1249 goto sigbus;
1250
1251 case MIPS16e_swsp_op:
1252 reg = reg16to32[mips16inst.ri.rx];
1253 if (extended && cpu_has_mips16e2)
1254 switch (mips16inst.ri.imm >> 5) {
1255 case 0: /* SWSP */
1256 case 1: /* SWGP */
1257 break;
1258 case 2: /* SHGP */
1259 opcode = MIPS16e_sh_op;
1260 break;
1261 default:
1262 goto sigbus;
1263 }
1264 break;
1265
1266 case MIPS16e_lwpc_op:
1267 reg = reg16to32[mips16inst.ri.rx];
1268 break;
1269
1270 case MIPS16e_lwsp_op:
1271 reg = reg16to32[mips16inst.ri.rx];
1272 if (extended && cpu_has_mips16e2)
1273 switch (mips16inst.ri.imm >> 5) {
1274 case 0: /* LWSP */
1275 case 1: /* LWGP */
1276 break;
1277 case 2: /* LHGP */
1278 opcode = MIPS16e_lh_op;
1279 break;
1280 case 4: /* LHUGP */
1281 opcode = MIPS16e_lhu_op;
1282 break;
1283 default:
1284 goto sigbus;
1285 }
1286 break;
1287
1288 case MIPS16e_i8_op:
1289 if (mips16inst.i8.func != MIPS16e_swrasp_func)
1290 goto sigbus;
1291 reg = 29; /* GPRSP */
1292 break;
1293
1294 default:
1295 reg = reg16to32[mips16inst.rri.ry];
1296 break;
1297 }
1298
1299 switch (opcode) {
1300
1301 case MIPS16e_lb_op:
1302 case MIPS16e_lbu_op:
1303 case MIPS16e_sb_op:
1304 goto sigbus;
1305
1306 case MIPS16e_lh_op:
1307 if (user && !access_ok(addr, 2))
1308 goto sigbus;
1309
1310 LoadHW(addr, value, res);
1311 if (res)
1312 goto fault;
1313 MIPS16e_compute_return_epc(regs, &oldinst);
1314 regs->regs[reg] = value;
1315 break;
1316
1317 case MIPS16e_lhu_op:
1318 if (user && !access_ok(addr, 2))
1319 goto sigbus;
1320
1321 LoadHWU(addr, value, res);
1322 if (res)
1323 goto fault;
1324 MIPS16e_compute_return_epc(regs, &oldinst);
1325 regs->regs[reg] = value;
1326 break;
1327
1328 case MIPS16e_lw_op:
1329 case MIPS16e_lwpc_op:
1330 case MIPS16e_lwsp_op:
1331 if (user && !access_ok(addr, 4))
1332 goto sigbus;
1333
1334 LoadW(addr, value, res);
1335 if (res)
1336 goto fault;
1337 MIPS16e_compute_return_epc(regs, &oldinst);
1338 regs->regs[reg] = value;
1339 break;
1340
1341 case MIPS16e_lwu_op:
1342#ifdef CONFIG_64BIT
1343 /*
1344 * A 32-bit kernel might be running on a 64-bit processor. But
1345 * if we're on a 32-bit processor and an i-cache incoherency
1346 * or race makes us see a 64-bit instruction here the sdl/sdr
1347 * would blow up, so for now we don't handle unaligned 64-bit
1348 * instructions on 32-bit kernels.
1349 */
1350 if (user && !access_ok(addr, 4))
1351 goto sigbus;
1352
1353 LoadWU(addr, value, res);
1354 if (res)
1355 goto fault;
1356 MIPS16e_compute_return_epc(regs, &oldinst);
1357 regs->regs[reg] = value;
1358 break;
1359#endif /* CONFIG_64BIT */
1360
1361 /* Cannot handle 64-bit instructions in 32-bit kernel */
1362 goto sigill;
1363
1364 case MIPS16e_ld_op:
1365loadDW:
1366#ifdef CONFIG_64BIT
1367 /*
1368 * A 32-bit kernel might be running on a 64-bit processor. But
1369 * if we're on a 32-bit processor and an i-cache incoherency
1370 * or race makes us see a 64-bit instruction here the sdl/sdr
1371 * would blow up, so for now we don't handle unaligned 64-bit
1372 * instructions on 32-bit kernels.
1373 */
1374 if (user && !access_ok(addr, 8))
1375 goto sigbus;
1376
1377 LoadDW(addr, value, res);
1378 if (res)
1379 goto fault;
1380 MIPS16e_compute_return_epc(regs, &oldinst);
1381 regs->regs[reg] = value;
1382 break;
1383#endif /* CONFIG_64BIT */
1384
1385 /* Cannot handle 64-bit instructions in 32-bit kernel */
1386 goto sigill;
1387
1388 case MIPS16e_sh_op:
1389 if (user && !access_ok(addr, 2))
1390 goto sigbus;
1391
1392 MIPS16e_compute_return_epc(regs, &oldinst);
1393 value = regs->regs[reg];
1394 StoreHW(addr, value, res);
1395 if (res)
1396 goto fault;
1397 break;
1398
1399 case MIPS16e_sw_op:
1400 case MIPS16e_swsp_op:
1401 case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */
1402 if (user && !access_ok(addr, 4))
1403 goto sigbus;
1404
1405 MIPS16e_compute_return_epc(regs, &oldinst);
1406 value = regs->regs[reg];
1407 StoreW(addr, value, res);
1408 if (res)
1409 goto fault;
1410 break;
1411
1412 case MIPS16e_sd_op:
1413writeDW:
1414#ifdef CONFIG_64BIT
1415 /*
1416 * A 32-bit kernel might be running on a 64-bit processor. But
1417 * if we're on a 32-bit processor and an i-cache incoherency
1418 * or race makes us see a 64-bit instruction here the sdl/sdr
1419 * would blow up, so for now we don't handle unaligned 64-bit
1420 * instructions on 32-bit kernels.
1421 */
1422 if (user && !access_ok(addr, 8))
1423 goto sigbus;
1424
1425 MIPS16e_compute_return_epc(regs, &oldinst);
1426 value = regs->regs[reg];
1427 StoreDW(addr, value, res);
1428 if (res)
1429 goto fault;
1430 break;
1431#endif /* CONFIG_64BIT */
1432
1433 /* Cannot handle 64-bit instructions in 32-bit kernel */
1434 goto sigill;
1435
1436 default:
1437 /*
1438 * Pheeee... We encountered an yet unknown instruction or
1439 * cache coherence problem. Die sucker, die ...
1440 */
1441 goto sigill;
1442 }
1443
1444#ifdef CONFIG_DEBUG_FS
1445 unaligned_instructions++;
1446#endif
1447
1448 return;
1449
1450fault:
1451 /* roll back jump/branch */
1452 regs->cp0_epc = origpc;
1453 regs->regs[31] = orig31;
1454 /* Did we have an exception handler installed? */
1455 if (fixup_exception(regs))
1456 return;
1457
1458 die_if_kernel("Unhandled kernel unaligned access", regs);
1459 force_sig(SIGSEGV);
1460
1461 return;
1462
1463sigbus:
1464 die_if_kernel("Unhandled kernel unaligned access", regs);
1465 force_sig(SIGBUS);
1466
1467 return;
1468
1469sigill:
1470 die_if_kernel
1471 ("Unhandled kernel unaligned access or invalid instruction", regs);
1472 force_sig(SIGILL);
1473}
1474
1475asmlinkage void do_ade(struct pt_regs *regs)
1476{
1477 enum ctx_state prev_state;
1478 unsigned int *pc;
1479
1480 prev_state = exception_enter();
1481 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS,
1482 1, regs, regs->cp0_badvaddr);
1483
1484#ifdef CONFIG_64BIT
1485 /*
1486 * check, if we are hitting space between CPU implemented maximum
1487 * virtual user address and 64bit maximum virtual user address
1488 * and do exception handling to get EFAULTs for get_user/put_user
1489 */
1490 if ((regs->cp0_badvaddr >= (1UL << cpu_vmbits)) &&
1491 (regs->cp0_badvaddr < XKSSEG)) {
1492 if (fixup_exception(regs)) {
1493 current->thread.cp0_baduaddr = regs->cp0_badvaddr;
1494 return;
1495 }
1496 goto sigbus;
1497 }
1498#endif
1499
1500 /*
1501 * Did we catch a fault trying to load an instruction?
1502 */
1503 if (regs->cp0_badvaddr == regs->cp0_epc)
1504 goto sigbus;
1505
1506 if (user_mode(regs) && !test_thread_flag(TIF_FIXADE))
1507 goto sigbus;
1508 if (unaligned_action == UNALIGNED_ACTION_SIGNAL)
1509 goto sigbus;
1510
1511 /*
1512 * Do branch emulation only if we didn't forward the exception.
1513 * This is all so but ugly ...
1514 */
1515
1516 /*
1517 * Are we running in microMIPS mode?
1518 */
1519 if (get_isa16_mode(regs->cp0_epc)) {
1520 /*
1521 * Did we catch a fault trying to load an instruction in
1522 * 16-bit mode?
1523 */
1524 if (regs->cp0_badvaddr == msk_isa16_mode(regs->cp0_epc))
1525 goto sigbus;
1526 if (unaligned_action == UNALIGNED_ACTION_SHOW)
1527 show_registers(regs);
1528
1529 if (cpu_has_mmips) {
1530 emulate_load_store_microMIPS(regs,
1531 (void __user *)regs->cp0_badvaddr);
1532 return;
1533 }
1534
1535 if (cpu_has_mips16) {
1536 emulate_load_store_MIPS16e(regs,
1537 (void __user *)regs->cp0_badvaddr);
1538 return;
1539 }
1540
1541 goto sigbus;
1542 }
1543
1544 if (unaligned_action == UNALIGNED_ACTION_SHOW)
1545 show_registers(regs);
1546 pc = (unsigned int *)exception_epc(regs);
1547
1548 emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc);
1549
1550 return;
1551
1552sigbus:
1553 die_if_kernel("Kernel unaligned instruction access", regs);
1554 force_sig(SIGBUS);
1555
1556 /*
1557 * XXX On return from the signal handler we should advance the epc
1558 */
1559 exception_exit(prev_state);
1560}
1561
1562#ifdef CONFIG_DEBUG_FS
1563static int __init debugfs_unaligned(void)
1564{
1565 debugfs_create_u32("unaligned_instructions", S_IRUGO, mips_debugfs_dir,
1566 &unaligned_instructions);
1567 debugfs_create_u32("unaligned_action", S_IRUGO | S_IWUSR,
1568 mips_debugfs_dir, &unaligned_action);
1569 return 0;
1570}
1571arch_initcall(debugfs_unaligned);
1572#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/debug.h>
89#include <asm/fpu.h>
90#include <asm/fpu_emulator.h>
91#include <asm/inst.h>
92#include <asm/uaccess.h>
93
94#define STR(x) __STR(x)
95#define __STR(x) #x
96
97enum {
98 UNALIGNED_ACTION_QUIET,
99 UNALIGNED_ACTION_SIGNAL,
100 UNALIGNED_ACTION_SHOW,
101};
102#ifdef CONFIG_DEBUG_FS
103static u32 unaligned_instructions;
104static u32 unaligned_action;
105#else
106#define unaligned_action UNALIGNED_ACTION_QUIET
107#endif
108extern void show_registers(struct pt_regs *regs);
109
110#ifdef __BIG_ENDIAN
111#define _LoadHW(addr, value, res, type) \
112do { \
113 __asm__ __volatile__ (".set\tnoat\n" \
114 "1:\t"type##_lb("%0", "0(%2)")"\n" \
115 "2:\t"type##_lbu("$1", "1(%2)")"\n\t"\
116 "sll\t%0, 0x8\n\t" \
117 "or\t%0, $1\n\t" \
118 "li\t%1, 0\n" \
119 "3:\t.set\tat\n\t" \
120 ".insn\n\t" \
121 ".section\t.fixup,\"ax\"\n\t" \
122 "4:\tli\t%1, %3\n\t" \
123 "j\t3b\n\t" \
124 ".previous\n\t" \
125 ".section\t__ex_table,\"a\"\n\t" \
126 STR(PTR)"\t1b, 4b\n\t" \
127 STR(PTR)"\t2b, 4b\n\t" \
128 ".previous" \
129 : "=&r" (value), "=r" (res) \
130 : "r" (addr), "i" (-EFAULT)); \
131} while(0)
132
133#ifndef CONFIG_CPU_MIPSR6
134#define _LoadW(addr, value, res, type) \
135do { \
136 __asm__ __volatile__ ( \
137 "1:\t"type##_lwl("%0", "(%2)")"\n" \
138 "2:\t"type##_lwr("%0", "3(%2)")"\n\t"\
139 "li\t%1, 0\n" \
140 "3:\n\t" \
141 ".insn\n\t" \
142 ".section\t.fixup,\"ax\"\n\t" \
143 "4:\tli\t%1, %3\n\t" \
144 "j\t3b\n\t" \
145 ".previous\n\t" \
146 ".section\t__ex_table,\"a\"\n\t" \
147 STR(PTR)"\t1b, 4b\n\t" \
148 STR(PTR)"\t2b, 4b\n\t" \
149 ".previous" \
150 : "=&r" (value), "=r" (res) \
151 : "r" (addr), "i" (-EFAULT)); \
152} while(0)
153
154#else
155/* MIPSR6 has no lwl instruction */
156#define _LoadW(addr, value, res, type) \
157do { \
158 __asm__ __volatile__ ( \
159 ".set\tpush\n" \
160 ".set\tnoat\n\t" \
161 "1:"type##_lb("%0", "0(%2)")"\n\t" \
162 "2:"type##_lbu("$1", "1(%2)")"\n\t" \
163 "sll\t%0, 0x8\n\t" \
164 "or\t%0, $1\n\t" \
165 "3:"type##_lbu("$1", "2(%2)")"\n\t" \
166 "sll\t%0, 0x8\n\t" \
167 "or\t%0, $1\n\t" \
168 "4:"type##_lbu("$1", "3(%2)")"\n\t" \
169 "sll\t%0, 0x8\n\t" \
170 "or\t%0, $1\n\t" \
171 "li\t%1, 0\n" \
172 ".set\tpop\n" \
173 "10:\n\t" \
174 ".insn\n\t" \
175 ".section\t.fixup,\"ax\"\n\t" \
176 "11:\tli\t%1, %3\n\t" \
177 "j\t10b\n\t" \
178 ".previous\n\t" \
179 ".section\t__ex_table,\"a\"\n\t" \
180 STR(PTR)"\t1b, 11b\n\t" \
181 STR(PTR)"\t2b, 11b\n\t" \
182 STR(PTR)"\t3b, 11b\n\t" \
183 STR(PTR)"\t4b, 11b\n\t" \
184 ".previous" \
185 : "=&r" (value), "=r" (res) \
186 : "r" (addr), "i" (-EFAULT)); \
187} while(0)
188
189#endif /* CONFIG_CPU_MIPSR6 */
190
191#define _LoadHWU(addr, value, res, type) \
192do { \
193 __asm__ __volatile__ ( \
194 ".set\tnoat\n" \
195 "1:\t"type##_lbu("%0", "0(%2)")"\n" \
196 "2:\t"type##_lbu("$1", "1(%2)")"\n\t"\
197 "sll\t%0, 0x8\n\t" \
198 "or\t%0, $1\n\t" \
199 "li\t%1, 0\n" \
200 "3:\n\t" \
201 ".insn\n\t" \
202 ".set\tat\n\t" \
203 ".section\t.fixup,\"ax\"\n\t" \
204 "4:\tli\t%1, %3\n\t" \
205 "j\t3b\n\t" \
206 ".previous\n\t" \
207 ".section\t__ex_table,\"a\"\n\t" \
208 STR(PTR)"\t1b, 4b\n\t" \
209 STR(PTR)"\t2b, 4b\n\t" \
210 ".previous" \
211 : "=&r" (value), "=r" (res) \
212 : "r" (addr), "i" (-EFAULT)); \
213} while(0)
214
215#ifndef CONFIG_CPU_MIPSR6
216#define _LoadWU(addr, value, res, type) \
217do { \
218 __asm__ __volatile__ ( \
219 "1:\t"type##_lwl("%0", "(%2)")"\n" \
220 "2:\t"type##_lwr("%0", "3(%2)")"\n\t"\
221 "dsll\t%0, %0, 32\n\t" \
222 "dsrl\t%0, %0, 32\n\t" \
223 "li\t%1, 0\n" \
224 "3:\n\t" \
225 ".insn\n\t" \
226 "\t.section\t.fixup,\"ax\"\n\t" \
227 "4:\tli\t%1, %3\n\t" \
228 "j\t3b\n\t" \
229 ".previous\n\t" \
230 ".section\t__ex_table,\"a\"\n\t" \
231 STR(PTR)"\t1b, 4b\n\t" \
232 STR(PTR)"\t2b, 4b\n\t" \
233 ".previous" \
234 : "=&r" (value), "=r" (res) \
235 : "r" (addr), "i" (-EFAULT)); \
236} while(0)
237
238#define _LoadDW(addr, value, res) \
239do { \
240 __asm__ __volatile__ ( \
241 "1:\tldl\t%0, (%2)\n" \
242 "2:\tldr\t%0, 7(%2)\n\t" \
243 "li\t%1, 0\n" \
244 "3:\n\t" \
245 ".insn\n\t" \
246 "\t.section\t.fixup,\"ax\"\n\t" \
247 "4:\tli\t%1, %3\n\t" \
248 "j\t3b\n\t" \
249 ".previous\n\t" \
250 ".section\t__ex_table,\"a\"\n\t" \
251 STR(PTR)"\t1b, 4b\n\t" \
252 STR(PTR)"\t2b, 4b\n\t" \
253 ".previous" \
254 : "=&r" (value), "=r" (res) \
255 : "r" (addr), "i" (-EFAULT)); \
256} while(0)
257
258#else
259/* MIPSR6 has not lwl and ldl instructions */
260#define _LoadWU(addr, value, res, type) \
261do { \
262 __asm__ __volatile__ ( \
263 ".set\tpush\n\t" \
264 ".set\tnoat\n\t" \
265 "1:"type##_lbu("%0", "0(%2)")"\n\t" \
266 "2:"type##_lbu("$1", "1(%2)")"\n\t" \
267 "sll\t%0, 0x8\n\t" \
268 "or\t%0, $1\n\t" \
269 "3:"type##_lbu("$1", "2(%2)")"\n\t" \
270 "sll\t%0, 0x8\n\t" \
271 "or\t%0, $1\n\t" \
272 "4:"type##_lbu("$1", "3(%2)")"\n\t" \
273 "sll\t%0, 0x8\n\t" \
274 "or\t%0, $1\n\t" \
275 "li\t%1, 0\n" \
276 ".set\tpop\n" \
277 "10:\n\t" \
278 ".insn\n\t" \
279 ".section\t.fixup,\"ax\"\n\t" \
280 "11:\tli\t%1, %3\n\t" \
281 "j\t10b\n\t" \
282 ".previous\n\t" \
283 ".section\t__ex_table,\"a\"\n\t" \
284 STR(PTR)"\t1b, 11b\n\t" \
285 STR(PTR)"\t2b, 11b\n\t" \
286 STR(PTR)"\t3b, 11b\n\t" \
287 STR(PTR)"\t4b, 11b\n\t" \
288 ".previous" \
289 : "=&r" (value), "=r" (res) \
290 : "r" (addr), "i" (-EFAULT)); \
291} while(0)
292
293#define _LoadDW(addr, value, res) \
294do { \
295 __asm__ __volatile__ ( \
296 ".set\tpush\n\t" \
297 ".set\tnoat\n\t" \
298 "1:lb\t%0, 0(%2)\n\t" \
299 "2:lbu\t $1, 1(%2)\n\t" \
300 "dsll\t%0, 0x8\n\t" \
301 "or\t%0, $1\n\t" \
302 "3:lbu\t$1, 2(%2)\n\t" \
303 "dsll\t%0, 0x8\n\t" \
304 "or\t%0, $1\n\t" \
305 "4:lbu\t$1, 3(%2)\n\t" \
306 "dsll\t%0, 0x8\n\t" \
307 "or\t%0, $1\n\t" \
308 "5:lbu\t$1, 4(%2)\n\t" \
309 "dsll\t%0, 0x8\n\t" \
310 "or\t%0, $1\n\t" \
311 "6:lbu\t$1, 5(%2)\n\t" \
312 "dsll\t%0, 0x8\n\t" \
313 "or\t%0, $1\n\t" \
314 "7:lbu\t$1, 6(%2)\n\t" \
315 "dsll\t%0, 0x8\n\t" \
316 "or\t%0, $1\n\t" \
317 "8:lbu\t$1, 7(%2)\n\t" \
318 "dsll\t%0, 0x8\n\t" \
319 "or\t%0, $1\n\t" \
320 "li\t%1, 0\n" \
321 ".set\tpop\n\t" \
322 "10:\n\t" \
323 ".insn\n\t" \
324 ".section\t.fixup,\"ax\"\n\t" \
325 "11:\tli\t%1, %3\n\t" \
326 "j\t10b\n\t" \
327 ".previous\n\t" \
328 ".section\t__ex_table,\"a\"\n\t" \
329 STR(PTR)"\t1b, 11b\n\t" \
330 STR(PTR)"\t2b, 11b\n\t" \
331 STR(PTR)"\t3b, 11b\n\t" \
332 STR(PTR)"\t4b, 11b\n\t" \
333 STR(PTR)"\t5b, 11b\n\t" \
334 STR(PTR)"\t6b, 11b\n\t" \
335 STR(PTR)"\t7b, 11b\n\t" \
336 STR(PTR)"\t8b, 11b\n\t" \
337 ".previous" \
338 : "=&r" (value), "=r" (res) \
339 : "r" (addr), "i" (-EFAULT)); \
340} while(0)
341
342#endif /* CONFIG_CPU_MIPSR6 */
343
344
345#define _StoreHW(addr, value, res, type) \
346do { \
347 __asm__ __volatile__ ( \
348 ".set\tnoat\n" \
349 "1:\t"type##_sb("%1", "1(%2)")"\n" \
350 "srl\t$1, %1, 0x8\n" \
351 "2:\t"type##_sb("$1", "0(%2)")"\n" \
352 ".set\tat\n\t" \
353 "li\t%0, 0\n" \
354 "3:\n\t" \
355 ".insn\n\t" \
356 ".section\t.fixup,\"ax\"\n\t" \
357 "4:\tli\t%0, %3\n\t" \
358 "j\t3b\n\t" \
359 ".previous\n\t" \
360 ".section\t__ex_table,\"a\"\n\t" \
361 STR(PTR)"\t1b, 4b\n\t" \
362 STR(PTR)"\t2b, 4b\n\t" \
363 ".previous" \
364 : "=r" (res) \
365 : "r" (value), "r" (addr), "i" (-EFAULT));\
366} while(0)
367
368#ifndef CONFIG_CPU_MIPSR6
369#define _StoreW(addr, value, res, type) \
370do { \
371 __asm__ __volatile__ ( \
372 "1:\t"type##_swl("%1", "(%2)")"\n" \
373 "2:\t"type##_swr("%1", "3(%2)")"\n\t"\
374 "li\t%0, 0\n" \
375 "3:\n\t" \
376 ".insn\n\t" \
377 ".section\t.fixup,\"ax\"\n\t" \
378 "4:\tli\t%0, %3\n\t" \
379 "j\t3b\n\t" \
380 ".previous\n\t" \
381 ".section\t__ex_table,\"a\"\n\t" \
382 STR(PTR)"\t1b, 4b\n\t" \
383 STR(PTR)"\t2b, 4b\n\t" \
384 ".previous" \
385 : "=r" (res) \
386 : "r" (value), "r" (addr), "i" (-EFAULT)); \
387} while(0)
388
389#define _StoreDW(addr, value, res) \
390do { \
391 __asm__ __volatile__ ( \
392 "1:\tsdl\t%1,(%2)\n" \
393 "2:\tsdr\t%1, 7(%2)\n\t" \
394 "li\t%0, 0\n" \
395 "3:\n\t" \
396 ".insn\n\t" \
397 ".section\t.fixup,\"ax\"\n\t" \
398 "4:\tli\t%0, %3\n\t" \
399 "j\t3b\n\t" \
400 ".previous\n\t" \
401 ".section\t__ex_table,\"a\"\n\t" \
402 STR(PTR)"\t1b, 4b\n\t" \
403 STR(PTR)"\t2b, 4b\n\t" \
404 ".previous" \
405 : "=r" (res) \
406 : "r" (value), "r" (addr), "i" (-EFAULT)); \
407} while(0)
408
409#else
410/* MIPSR6 has no swl and sdl instructions */
411#define _StoreW(addr, value, res, type) \
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_MIPSR6 */
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#ifndef CONFIG_CPU_MIPSR6
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
534/* MIPSR6 has no 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_MIPSR6 */
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#ifndef CONFIG_CPU_MIPSR6
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
639/* MIPSR6 has not 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_MIPSR6 */
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#ifndef CONFIG_CPU_MIPSR6
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
788/* MIPSR6 has no 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_MIPSR6 */
865#endif
866
867#define LoadHWU(addr, value, res) _LoadHWU(addr, value, res, kernel)
868#define LoadHWUE(addr, value, res) _LoadHWU(addr, value, res, user)
869#define LoadWU(addr, value, res) _LoadWU(addr, value, res, kernel)
870#define LoadWUE(addr, value, res) _LoadWU(addr, value, res, user)
871#define LoadHW(addr, value, res) _LoadHW(addr, value, res, kernel)
872#define LoadHWE(addr, value, res) _LoadHW(addr, value, res, user)
873#define LoadW(addr, value, res) _LoadW(addr, value, res, kernel)
874#define LoadWE(addr, value, res) _LoadW(addr, value, res, user)
875#define LoadDW(addr, value, res) _LoadDW(addr, value, res)
876
877#define StoreHW(addr, value, res) _StoreHW(addr, value, res, kernel)
878#define StoreHWE(addr, value, res) _StoreHW(addr, value, res, user)
879#define StoreW(addr, value, res) _StoreW(addr, value, res, kernel)
880#define StoreWE(addr, value, res) _StoreW(addr, value, res, user)
881#define StoreDW(addr, value, res) _StoreDW(addr, value, res)
882
883static void emulate_load_store_insn(struct pt_regs *regs,
884 void __user *addr, unsigned int __user *pc)
885{
886 union mips_instruction insn;
887 unsigned long value;
888 unsigned int res, preempted;
889 unsigned long origpc;
890 unsigned long orig31;
891 void __user *fault_addr = NULL;
892#ifdef CONFIG_EVA
893 mm_segment_t seg;
894#endif
895 union fpureg *fpr;
896 enum msa_2b_fmt df;
897 unsigned int wd;
898 origpc = (unsigned long)pc;
899 orig31 = regs->regs[31];
900
901 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0);
902
903 /*
904 * This load never faults.
905 */
906 __get_user(insn.word, pc);
907
908 switch (insn.i_format.opcode) {
909 /*
910 * These are instructions that a compiler doesn't generate. We
911 * can assume therefore that the code is MIPS-aware and
912 * really buggy. Emulating these instructions would break the
913 * semantics anyway.
914 */
915 case ll_op:
916 case lld_op:
917 case sc_op:
918 case scd_op:
919
920 /*
921 * For these instructions the only way to create an address
922 * error is an attempted access to kernel/supervisor address
923 * space.
924 */
925 case ldl_op:
926 case ldr_op:
927 case lwl_op:
928 case lwr_op:
929 case sdl_op:
930 case sdr_op:
931 case swl_op:
932 case swr_op:
933 case lb_op:
934 case lbu_op:
935 case sb_op:
936 goto sigbus;
937
938 /*
939 * The remaining opcodes are the ones that are really of
940 * interest.
941 */
942#ifdef CONFIG_EVA
943 case spec3_op:
944 /*
945 * we can land here only from kernel accessing user memory,
946 * so we need to "switch" the address limit to user space, so
947 * address check can work properly.
948 */
949 seg = get_fs();
950 set_fs(USER_DS);
951 switch (insn.spec3_format.func) {
952 case lhe_op:
953 if (!access_ok(VERIFY_READ, addr, 2)) {
954 set_fs(seg);
955 goto sigbus;
956 }
957 LoadHWE(addr, value, res);
958 if (res) {
959 set_fs(seg);
960 goto fault;
961 }
962 compute_return_epc(regs);
963 regs->regs[insn.spec3_format.rt] = value;
964 break;
965 case lwe_op:
966 if (!access_ok(VERIFY_READ, addr, 4)) {
967 set_fs(seg);
968 goto sigbus;
969 }
970 LoadWE(addr, value, res);
971 if (res) {
972 set_fs(seg);
973 goto fault;
974 }
975 compute_return_epc(regs);
976 regs->regs[insn.spec3_format.rt] = value;
977 break;
978 case lhue_op:
979 if (!access_ok(VERIFY_READ, addr, 2)) {
980 set_fs(seg);
981 goto sigbus;
982 }
983 LoadHWUE(addr, value, res);
984 if (res) {
985 set_fs(seg);
986 goto fault;
987 }
988 compute_return_epc(regs);
989 regs->regs[insn.spec3_format.rt] = value;
990 break;
991 case she_op:
992 if (!access_ok(VERIFY_WRITE, addr, 2)) {
993 set_fs(seg);
994 goto sigbus;
995 }
996 compute_return_epc(regs);
997 value = regs->regs[insn.spec3_format.rt];
998 StoreHWE(addr, value, res);
999 if (res) {
1000 set_fs(seg);
1001 goto fault;
1002 }
1003 break;
1004 case swe_op:
1005 if (!access_ok(VERIFY_WRITE, addr, 4)) {
1006 set_fs(seg);
1007 goto sigbus;
1008 }
1009 compute_return_epc(regs);
1010 value = regs->regs[insn.spec3_format.rt];
1011 StoreWE(addr, value, res);
1012 if (res) {
1013 set_fs(seg);
1014 goto fault;
1015 }
1016 break;
1017 default:
1018 set_fs(seg);
1019 goto sigill;
1020 }
1021 set_fs(seg);
1022 break;
1023#endif
1024 case lh_op:
1025 if (!access_ok(VERIFY_READ, addr, 2))
1026 goto sigbus;
1027
1028 if (config_enabled(CONFIG_EVA)) {
1029 if (segment_eq(get_fs(), get_ds()))
1030 LoadHW(addr, value, res);
1031 else
1032 LoadHWE(addr, value, res);
1033 } else {
1034 LoadHW(addr, value, res);
1035 }
1036
1037 if (res)
1038 goto fault;
1039 compute_return_epc(regs);
1040 regs->regs[insn.i_format.rt] = value;
1041 break;
1042
1043 case lw_op:
1044 if (!access_ok(VERIFY_READ, addr, 4))
1045 goto sigbus;
1046
1047 if (config_enabled(CONFIG_EVA)) {
1048 if (segment_eq(get_fs(), get_ds()))
1049 LoadW(addr, value, res);
1050 else
1051 LoadWE(addr, value, res);
1052 } else {
1053 LoadW(addr, value, res);
1054 }
1055
1056 if (res)
1057 goto fault;
1058 compute_return_epc(regs);
1059 regs->regs[insn.i_format.rt] = value;
1060 break;
1061
1062 case lhu_op:
1063 if (!access_ok(VERIFY_READ, addr, 2))
1064 goto sigbus;
1065
1066 if (config_enabled(CONFIG_EVA)) {
1067 if (segment_eq(get_fs(), get_ds()))
1068 LoadHWU(addr, value, res);
1069 else
1070 LoadHWUE(addr, value, res);
1071 } else {
1072 LoadHWU(addr, value, res);
1073 }
1074
1075 if (res)
1076 goto fault;
1077 compute_return_epc(regs);
1078 regs->regs[insn.i_format.rt] = value;
1079 break;
1080
1081 case lwu_op:
1082#ifdef CONFIG_64BIT
1083 /*
1084 * A 32-bit kernel might be running on a 64-bit processor. But
1085 * if we're on a 32-bit processor and an i-cache incoherency
1086 * or race makes us see a 64-bit instruction here the sdl/sdr
1087 * would blow up, so for now we don't handle unaligned 64-bit
1088 * instructions on 32-bit kernels.
1089 */
1090 if (!access_ok(VERIFY_READ, addr, 4))
1091 goto sigbus;
1092
1093 LoadWU(addr, value, res);
1094 if (res)
1095 goto fault;
1096 compute_return_epc(regs);
1097 regs->regs[insn.i_format.rt] = value;
1098 break;
1099#endif /* CONFIG_64BIT */
1100
1101 /* Cannot handle 64-bit instructions in 32-bit kernel */
1102 goto sigill;
1103
1104 case ld_op:
1105#ifdef CONFIG_64BIT
1106 /*
1107 * A 32-bit kernel might be running on a 64-bit processor. But
1108 * if we're on a 32-bit processor and an i-cache incoherency
1109 * or race makes us see a 64-bit instruction here the sdl/sdr
1110 * would blow up, so for now we don't handle unaligned 64-bit
1111 * instructions on 32-bit kernels.
1112 */
1113 if (!access_ok(VERIFY_READ, addr, 8))
1114 goto sigbus;
1115
1116 LoadDW(addr, value, res);
1117 if (res)
1118 goto fault;
1119 compute_return_epc(regs);
1120 regs->regs[insn.i_format.rt] = value;
1121 break;
1122#endif /* CONFIG_64BIT */
1123
1124 /* Cannot handle 64-bit instructions in 32-bit kernel */
1125 goto sigill;
1126
1127 case sh_op:
1128 if (!access_ok(VERIFY_WRITE, addr, 2))
1129 goto sigbus;
1130
1131 compute_return_epc(regs);
1132 value = regs->regs[insn.i_format.rt];
1133
1134 if (config_enabled(CONFIG_EVA)) {
1135 if (segment_eq(get_fs(), get_ds()))
1136 StoreHW(addr, value, res);
1137 else
1138 StoreHWE(addr, value, res);
1139 } else {
1140 StoreHW(addr, value, res);
1141 }
1142
1143 if (res)
1144 goto fault;
1145 break;
1146
1147 case sw_op:
1148 if (!access_ok(VERIFY_WRITE, addr, 4))
1149 goto sigbus;
1150
1151 compute_return_epc(regs);
1152 value = regs->regs[insn.i_format.rt];
1153
1154 if (config_enabled(CONFIG_EVA)) {
1155 if (segment_eq(get_fs(), get_ds()))
1156 StoreW(addr, value, res);
1157 else
1158 StoreWE(addr, value, res);
1159 } else {
1160 StoreW(addr, value, res);
1161 }
1162
1163 if (res)
1164 goto fault;
1165 break;
1166
1167 case sd_op:
1168#ifdef CONFIG_64BIT
1169 /*
1170 * A 32-bit kernel might be running on a 64-bit processor. But
1171 * if we're on a 32-bit processor and an i-cache incoherency
1172 * or race makes us see a 64-bit instruction here the sdl/sdr
1173 * would blow up, so for now we don't handle unaligned 64-bit
1174 * instructions on 32-bit kernels.
1175 */
1176 if (!access_ok(VERIFY_WRITE, addr, 8))
1177 goto sigbus;
1178
1179 compute_return_epc(regs);
1180 value = regs->regs[insn.i_format.rt];
1181 StoreDW(addr, value, res);
1182 if (res)
1183 goto fault;
1184 break;
1185#endif /* CONFIG_64BIT */
1186
1187 /* Cannot handle 64-bit instructions in 32-bit kernel */
1188 goto sigill;
1189
1190 case lwc1_op:
1191 case ldc1_op:
1192 case swc1_op:
1193 case sdc1_op:
1194 die_if_kernel("Unaligned FP access in kernel code", regs);
1195 BUG_ON(!used_math());
1196
1197 lose_fpu(1); /* Save FPU state for the emulator. */
1198 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
1199 &fault_addr);
1200 own_fpu(1); /* Restore FPU state. */
1201
1202 /* Signal if something went wrong. */
1203 process_fpemu_return(res, fault_addr, 0);
1204
1205 if (res == 0)
1206 break;
1207 return;
1208
1209 case msa_op:
1210 if (!cpu_has_msa)
1211 goto sigill;
1212
1213 /*
1214 * If we've reached this point then userland should have taken
1215 * the MSA disabled exception & initialised vector context at
1216 * some point in the past.
1217 */
1218 BUG_ON(!thread_msa_context_live());
1219
1220 df = insn.msa_mi10_format.df;
1221 wd = insn.msa_mi10_format.wd;
1222 fpr = ¤t->thread.fpu.fpr[wd];
1223
1224 switch (insn.msa_mi10_format.func) {
1225 case msa_ld_op:
1226 if (!access_ok(VERIFY_READ, addr, sizeof(*fpr)))
1227 goto sigbus;
1228
1229 do {
1230 /*
1231 * If we have live MSA context keep track of
1232 * whether we get preempted in order to avoid
1233 * the register context we load being clobbered
1234 * by the live context as it's saved during
1235 * preemption. If we don't have live context
1236 * then it can't be saved to clobber the value
1237 * we load.
1238 */
1239 preempted = test_thread_flag(TIF_USEDMSA);
1240
1241 res = __copy_from_user_inatomic(fpr, addr,
1242 sizeof(*fpr));
1243 if (res)
1244 goto fault;
1245
1246 /*
1247 * Update the hardware register if it is in use
1248 * by the task in this quantum, in order to
1249 * avoid having to save & restore the whole
1250 * vector context.
1251 */
1252 preempt_disable();
1253 if (test_thread_flag(TIF_USEDMSA)) {
1254 write_msa_wr(wd, fpr, df);
1255 preempted = 0;
1256 }
1257 preempt_enable();
1258 } while (preempted);
1259 break;
1260
1261 case msa_st_op:
1262 if (!access_ok(VERIFY_WRITE, addr, sizeof(*fpr)))
1263 goto sigbus;
1264
1265 /*
1266 * Update from the hardware register if it is in use by
1267 * the task in this quantum, in order to avoid having to
1268 * save & restore the whole vector context.
1269 */
1270 preempt_disable();
1271 if (test_thread_flag(TIF_USEDMSA))
1272 read_msa_wr(wd, fpr, df);
1273 preempt_enable();
1274
1275 res = __copy_to_user_inatomic(addr, fpr, sizeof(*fpr));
1276 if (res)
1277 goto fault;
1278 break;
1279
1280 default:
1281 goto sigbus;
1282 }
1283
1284 compute_return_epc(regs);
1285 break;
1286
1287#ifndef CONFIG_CPU_MIPSR6
1288 /*
1289 * COP2 is available to implementor for application specific use.
1290 * It's up to applications to register a notifier chain and do
1291 * whatever they have to do, including possible sending of signals.
1292 *
1293 * This instruction has been reallocated in Release 6
1294 */
1295 case lwc2_op:
1296 cu2_notifier_call_chain(CU2_LWC2_OP, regs);
1297 break;
1298
1299 case ldc2_op:
1300 cu2_notifier_call_chain(CU2_LDC2_OP, regs);
1301 break;
1302
1303 case swc2_op:
1304 cu2_notifier_call_chain(CU2_SWC2_OP, regs);
1305 break;
1306
1307 case sdc2_op:
1308 cu2_notifier_call_chain(CU2_SDC2_OP, regs);
1309 break;
1310#endif
1311 default:
1312 /*
1313 * Pheeee... We encountered an yet unknown instruction or
1314 * cache coherence problem. Die sucker, die ...
1315 */
1316 goto sigill;
1317 }
1318
1319#ifdef CONFIG_DEBUG_FS
1320 unaligned_instructions++;
1321#endif
1322
1323 return;
1324
1325fault:
1326 /* roll back jump/branch */
1327 regs->cp0_epc = origpc;
1328 regs->regs[31] = orig31;
1329 /* Did we have an exception handler installed? */
1330 if (fixup_exception(regs))
1331 return;
1332
1333 die_if_kernel("Unhandled kernel unaligned access", regs);
1334 force_sig(SIGSEGV, current);
1335
1336 return;
1337
1338sigbus:
1339 die_if_kernel("Unhandled kernel unaligned access", regs);
1340 force_sig(SIGBUS, current);
1341
1342 return;
1343
1344sigill:
1345 die_if_kernel
1346 ("Unhandled kernel unaligned access or invalid instruction", regs);
1347 force_sig(SIGILL, current);
1348}
1349
1350/* Recode table from 16-bit register notation to 32-bit GPR. */
1351const int reg16to32[] = { 16, 17, 2, 3, 4, 5, 6, 7 };
1352
1353/* Recode table from 16-bit STORE register notation to 32-bit GPR. */
1354const int reg16to32st[] = { 0, 17, 2, 3, 4, 5, 6, 7 };
1355
1356static void emulate_load_store_microMIPS(struct pt_regs *regs,
1357 void __user *addr)
1358{
1359 unsigned long value;
1360 unsigned int res;
1361 int i;
1362 unsigned int reg = 0, rvar;
1363 unsigned long orig31;
1364 u16 __user *pc16;
1365 u16 halfword;
1366 unsigned int word;
1367 unsigned long origpc, contpc;
1368 union mips_instruction insn;
1369 struct mm_decoded_insn mminsn;
1370 void __user *fault_addr = NULL;
1371
1372 origpc = regs->cp0_epc;
1373 orig31 = regs->regs[31];
1374
1375 mminsn.micro_mips_mode = 1;
1376
1377 /*
1378 * This load never faults.
1379 */
1380 pc16 = (unsigned short __user *)msk_isa16_mode(regs->cp0_epc);
1381 __get_user(halfword, pc16);
1382 pc16++;
1383 contpc = regs->cp0_epc + 2;
1384 word = ((unsigned int)halfword << 16);
1385 mminsn.pc_inc = 2;
1386
1387 if (!mm_insn_16bit(halfword)) {
1388 __get_user(halfword, pc16);
1389 pc16++;
1390 contpc = regs->cp0_epc + 4;
1391 mminsn.pc_inc = 4;
1392 word |= halfword;
1393 }
1394 mminsn.insn = word;
1395
1396 if (get_user(halfword, pc16))
1397 goto fault;
1398 mminsn.next_pc_inc = 2;
1399 word = ((unsigned int)halfword << 16);
1400
1401 if (!mm_insn_16bit(halfword)) {
1402 pc16++;
1403 if (get_user(halfword, pc16))
1404 goto fault;
1405 mminsn.next_pc_inc = 4;
1406 word |= halfword;
1407 }
1408 mminsn.next_insn = word;
1409
1410 insn = (union mips_instruction)(mminsn.insn);
1411 if (mm_isBranchInstr(regs, mminsn, &contpc))
1412 insn = (union mips_instruction)(mminsn.next_insn);
1413
1414 /* Parse instruction to find what to do */
1415
1416 switch (insn.mm_i_format.opcode) {
1417
1418 case mm_pool32a_op:
1419 switch (insn.mm_x_format.func) {
1420 case mm_lwxs_op:
1421 reg = insn.mm_x_format.rd;
1422 goto loadW;
1423 }
1424
1425 goto sigbus;
1426
1427 case mm_pool32b_op:
1428 switch (insn.mm_m_format.func) {
1429 case mm_lwp_func:
1430 reg = insn.mm_m_format.rd;
1431 if (reg == 31)
1432 goto sigbus;
1433
1434 if (!access_ok(VERIFY_READ, addr, 8))
1435 goto sigbus;
1436
1437 LoadW(addr, value, res);
1438 if (res)
1439 goto fault;
1440 regs->regs[reg] = value;
1441 addr += 4;
1442 LoadW(addr, value, res);
1443 if (res)
1444 goto fault;
1445 regs->regs[reg + 1] = value;
1446 goto success;
1447
1448 case mm_swp_func:
1449 reg = insn.mm_m_format.rd;
1450 if (reg == 31)
1451 goto sigbus;
1452
1453 if (!access_ok(VERIFY_WRITE, addr, 8))
1454 goto sigbus;
1455
1456 value = regs->regs[reg];
1457 StoreW(addr, value, res);
1458 if (res)
1459 goto fault;
1460 addr += 4;
1461 value = regs->regs[reg + 1];
1462 StoreW(addr, value, res);
1463 if (res)
1464 goto fault;
1465 goto success;
1466
1467 case mm_ldp_func:
1468#ifdef CONFIG_64BIT
1469 reg = insn.mm_m_format.rd;
1470 if (reg == 31)
1471 goto sigbus;
1472
1473 if (!access_ok(VERIFY_READ, addr, 16))
1474 goto sigbus;
1475
1476 LoadDW(addr, value, res);
1477 if (res)
1478 goto fault;
1479 regs->regs[reg] = value;
1480 addr += 8;
1481 LoadDW(addr, value, res);
1482 if (res)
1483 goto fault;
1484 regs->regs[reg + 1] = value;
1485 goto success;
1486#endif /* CONFIG_64BIT */
1487
1488 goto sigill;
1489
1490 case mm_sdp_func:
1491#ifdef CONFIG_64BIT
1492 reg = insn.mm_m_format.rd;
1493 if (reg == 31)
1494 goto sigbus;
1495
1496 if (!access_ok(VERIFY_WRITE, addr, 16))
1497 goto sigbus;
1498
1499 value = regs->regs[reg];
1500 StoreDW(addr, value, res);
1501 if (res)
1502 goto fault;
1503 addr += 8;
1504 value = regs->regs[reg + 1];
1505 StoreDW(addr, value, res);
1506 if (res)
1507 goto fault;
1508 goto success;
1509#endif /* CONFIG_64BIT */
1510
1511 goto sigill;
1512
1513 case mm_lwm32_func:
1514 reg = insn.mm_m_format.rd;
1515 rvar = reg & 0xf;
1516 if ((rvar > 9) || !reg)
1517 goto sigill;
1518 if (reg & 0x10) {
1519 if (!access_ok
1520 (VERIFY_READ, addr, 4 * (rvar + 1)))
1521 goto sigbus;
1522 } else {
1523 if (!access_ok(VERIFY_READ, addr, 4 * rvar))
1524 goto sigbus;
1525 }
1526 if (rvar == 9)
1527 rvar = 8;
1528 for (i = 16; rvar; rvar--, i++) {
1529 LoadW(addr, value, res);
1530 if (res)
1531 goto fault;
1532 addr += 4;
1533 regs->regs[i] = value;
1534 }
1535 if ((reg & 0xf) == 9) {
1536 LoadW(addr, value, res);
1537 if (res)
1538 goto fault;
1539 addr += 4;
1540 regs->regs[30] = value;
1541 }
1542 if (reg & 0x10) {
1543 LoadW(addr, value, res);
1544 if (res)
1545 goto fault;
1546 regs->regs[31] = value;
1547 }
1548 goto success;
1549
1550 case mm_swm32_func:
1551 reg = insn.mm_m_format.rd;
1552 rvar = reg & 0xf;
1553 if ((rvar > 9) || !reg)
1554 goto sigill;
1555 if (reg & 0x10) {
1556 if (!access_ok
1557 (VERIFY_WRITE, addr, 4 * (rvar + 1)))
1558 goto sigbus;
1559 } else {
1560 if (!access_ok(VERIFY_WRITE, addr, 4 * rvar))
1561 goto sigbus;
1562 }
1563 if (rvar == 9)
1564 rvar = 8;
1565 for (i = 16; rvar; rvar--, i++) {
1566 value = regs->regs[i];
1567 StoreW(addr, value, res);
1568 if (res)
1569 goto fault;
1570 addr += 4;
1571 }
1572 if ((reg & 0xf) == 9) {
1573 value = regs->regs[30];
1574 StoreW(addr, value, res);
1575 if (res)
1576 goto fault;
1577 addr += 4;
1578 }
1579 if (reg & 0x10) {
1580 value = regs->regs[31];
1581 StoreW(addr, value, res);
1582 if (res)
1583 goto fault;
1584 }
1585 goto success;
1586
1587 case mm_ldm_func:
1588#ifdef CONFIG_64BIT
1589 reg = insn.mm_m_format.rd;
1590 rvar = reg & 0xf;
1591 if ((rvar > 9) || !reg)
1592 goto sigill;
1593 if (reg & 0x10) {
1594 if (!access_ok
1595 (VERIFY_READ, addr, 8 * (rvar + 1)))
1596 goto sigbus;
1597 } else {
1598 if (!access_ok(VERIFY_READ, addr, 8 * rvar))
1599 goto sigbus;
1600 }
1601 if (rvar == 9)
1602 rvar = 8;
1603
1604 for (i = 16; rvar; rvar--, i++) {
1605 LoadDW(addr, value, res);
1606 if (res)
1607 goto fault;
1608 addr += 4;
1609 regs->regs[i] = value;
1610 }
1611 if ((reg & 0xf) == 9) {
1612 LoadDW(addr, value, res);
1613 if (res)
1614 goto fault;
1615 addr += 8;
1616 regs->regs[30] = value;
1617 }
1618 if (reg & 0x10) {
1619 LoadDW(addr, value, res);
1620 if (res)
1621 goto fault;
1622 regs->regs[31] = value;
1623 }
1624 goto success;
1625#endif /* CONFIG_64BIT */
1626
1627 goto sigill;
1628
1629 case mm_sdm_func:
1630#ifdef CONFIG_64BIT
1631 reg = insn.mm_m_format.rd;
1632 rvar = reg & 0xf;
1633 if ((rvar > 9) || !reg)
1634 goto sigill;
1635 if (reg & 0x10) {
1636 if (!access_ok
1637 (VERIFY_WRITE, addr, 8 * (rvar + 1)))
1638 goto sigbus;
1639 } else {
1640 if (!access_ok(VERIFY_WRITE, addr, 8 * rvar))
1641 goto sigbus;
1642 }
1643 if (rvar == 9)
1644 rvar = 8;
1645
1646 for (i = 16; rvar; rvar--, i++) {
1647 value = regs->regs[i];
1648 StoreDW(addr, value, res);
1649 if (res)
1650 goto fault;
1651 addr += 8;
1652 }
1653 if ((reg & 0xf) == 9) {
1654 value = regs->regs[30];
1655 StoreDW(addr, value, res);
1656 if (res)
1657 goto fault;
1658 addr += 8;
1659 }
1660 if (reg & 0x10) {
1661 value = regs->regs[31];
1662 StoreDW(addr, value, res);
1663 if (res)
1664 goto fault;
1665 }
1666 goto success;
1667#endif /* CONFIG_64BIT */
1668
1669 goto sigill;
1670
1671 /* LWC2, SWC2, LDC2, SDC2 are not serviced */
1672 }
1673
1674 goto sigbus;
1675
1676 case mm_pool32c_op:
1677 switch (insn.mm_m_format.func) {
1678 case mm_lwu_func:
1679 reg = insn.mm_m_format.rd;
1680 goto loadWU;
1681 }
1682
1683 /* LL,SC,LLD,SCD are not serviced */
1684 goto sigbus;
1685
1686 case mm_pool32f_op:
1687 switch (insn.mm_x_format.func) {
1688 case mm_lwxc1_func:
1689 case mm_swxc1_func:
1690 case mm_ldxc1_func:
1691 case mm_sdxc1_func:
1692 goto fpu_emul;
1693 }
1694
1695 goto sigbus;
1696
1697 case mm_ldc132_op:
1698 case mm_sdc132_op:
1699 case mm_lwc132_op:
1700 case mm_swc132_op:
1701fpu_emul:
1702 /* roll back jump/branch */
1703 regs->cp0_epc = origpc;
1704 regs->regs[31] = orig31;
1705
1706 die_if_kernel("Unaligned FP access in kernel code", regs);
1707 BUG_ON(!used_math());
1708 BUG_ON(!is_fpu_owner());
1709
1710 lose_fpu(1); /* save the FPU state for the emulator */
1711 res = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1,
1712 &fault_addr);
1713 own_fpu(1); /* restore FPU state */
1714
1715 /* If something went wrong, signal */
1716 process_fpemu_return(res, fault_addr, 0);
1717
1718 if (res == 0)
1719 goto success;
1720 return;
1721
1722 case mm_lh32_op:
1723 reg = insn.mm_i_format.rt;
1724 goto loadHW;
1725
1726 case mm_lhu32_op:
1727 reg = insn.mm_i_format.rt;
1728 goto loadHWU;
1729
1730 case mm_lw32_op:
1731 reg = insn.mm_i_format.rt;
1732 goto loadW;
1733
1734 case mm_sh32_op:
1735 reg = insn.mm_i_format.rt;
1736 goto storeHW;
1737
1738 case mm_sw32_op:
1739 reg = insn.mm_i_format.rt;
1740 goto storeW;
1741
1742 case mm_ld32_op:
1743 reg = insn.mm_i_format.rt;
1744 goto loadDW;
1745
1746 case mm_sd32_op:
1747 reg = insn.mm_i_format.rt;
1748 goto storeDW;
1749
1750 case mm_pool16c_op:
1751 switch (insn.mm16_m_format.func) {
1752 case mm_lwm16_op:
1753 reg = insn.mm16_m_format.rlist;
1754 rvar = reg + 1;
1755 if (!access_ok(VERIFY_READ, addr, 4 * rvar))
1756 goto sigbus;
1757
1758 for (i = 16; rvar; rvar--, i++) {
1759 LoadW(addr, value, res);
1760 if (res)
1761 goto fault;
1762 addr += 4;
1763 regs->regs[i] = value;
1764 }
1765 LoadW(addr, value, res);
1766 if (res)
1767 goto fault;
1768 regs->regs[31] = value;
1769
1770 goto success;
1771
1772 case mm_swm16_op:
1773 reg = insn.mm16_m_format.rlist;
1774 rvar = reg + 1;
1775 if (!access_ok(VERIFY_WRITE, addr, 4 * rvar))
1776 goto sigbus;
1777
1778 for (i = 16; rvar; rvar--, i++) {
1779 value = regs->regs[i];
1780 StoreW(addr, value, res);
1781 if (res)
1782 goto fault;
1783 addr += 4;
1784 }
1785 value = regs->regs[31];
1786 StoreW(addr, value, res);
1787 if (res)
1788 goto fault;
1789
1790 goto success;
1791
1792 }
1793
1794 goto sigbus;
1795
1796 case mm_lhu16_op:
1797 reg = reg16to32[insn.mm16_rb_format.rt];
1798 goto loadHWU;
1799
1800 case mm_lw16_op:
1801 reg = reg16to32[insn.mm16_rb_format.rt];
1802 goto loadW;
1803
1804 case mm_sh16_op:
1805 reg = reg16to32st[insn.mm16_rb_format.rt];
1806 goto storeHW;
1807
1808 case mm_sw16_op:
1809 reg = reg16to32st[insn.mm16_rb_format.rt];
1810 goto storeW;
1811
1812 case mm_lwsp16_op:
1813 reg = insn.mm16_r5_format.rt;
1814 goto loadW;
1815
1816 case mm_swsp16_op:
1817 reg = insn.mm16_r5_format.rt;
1818 goto storeW;
1819
1820 case mm_lwgp16_op:
1821 reg = reg16to32[insn.mm16_r3_format.rt];
1822 goto loadW;
1823
1824 default:
1825 goto sigill;
1826 }
1827
1828loadHW:
1829 if (!access_ok(VERIFY_READ, addr, 2))
1830 goto sigbus;
1831
1832 LoadHW(addr, value, res);
1833 if (res)
1834 goto fault;
1835 regs->regs[reg] = value;
1836 goto success;
1837
1838loadHWU:
1839 if (!access_ok(VERIFY_READ, addr, 2))
1840 goto sigbus;
1841
1842 LoadHWU(addr, value, res);
1843 if (res)
1844 goto fault;
1845 regs->regs[reg] = value;
1846 goto success;
1847
1848loadW:
1849 if (!access_ok(VERIFY_READ, addr, 4))
1850 goto sigbus;
1851
1852 LoadW(addr, value, res);
1853 if (res)
1854 goto fault;
1855 regs->regs[reg] = value;
1856 goto success;
1857
1858loadWU:
1859#ifdef CONFIG_64BIT
1860 /*
1861 * A 32-bit kernel might be running on a 64-bit processor. But
1862 * if we're on a 32-bit processor and an i-cache incoherency
1863 * or race makes us see a 64-bit instruction here the sdl/sdr
1864 * would blow up, so for now we don't handle unaligned 64-bit
1865 * instructions on 32-bit kernels.
1866 */
1867 if (!access_ok(VERIFY_READ, addr, 4))
1868 goto sigbus;
1869
1870 LoadWU(addr, value, res);
1871 if (res)
1872 goto fault;
1873 regs->regs[reg] = value;
1874 goto success;
1875#endif /* CONFIG_64BIT */
1876
1877 /* Cannot handle 64-bit instructions in 32-bit kernel */
1878 goto sigill;
1879
1880loadDW:
1881#ifdef CONFIG_64BIT
1882 /*
1883 * A 32-bit kernel might be running on a 64-bit processor. But
1884 * if we're on a 32-bit processor and an i-cache incoherency
1885 * or race makes us see a 64-bit instruction here the sdl/sdr
1886 * would blow up, so for now we don't handle unaligned 64-bit
1887 * instructions on 32-bit kernels.
1888 */
1889 if (!access_ok(VERIFY_READ, addr, 8))
1890 goto sigbus;
1891
1892 LoadDW(addr, value, res);
1893 if (res)
1894 goto fault;
1895 regs->regs[reg] = value;
1896 goto success;
1897#endif /* CONFIG_64BIT */
1898
1899 /* Cannot handle 64-bit instructions in 32-bit kernel */
1900 goto sigill;
1901
1902storeHW:
1903 if (!access_ok(VERIFY_WRITE, addr, 2))
1904 goto sigbus;
1905
1906 value = regs->regs[reg];
1907 StoreHW(addr, value, res);
1908 if (res)
1909 goto fault;
1910 goto success;
1911
1912storeW:
1913 if (!access_ok(VERIFY_WRITE, addr, 4))
1914 goto sigbus;
1915
1916 value = regs->regs[reg];
1917 StoreW(addr, value, res);
1918 if (res)
1919 goto fault;
1920 goto success;
1921
1922storeDW:
1923#ifdef CONFIG_64BIT
1924 /*
1925 * A 32-bit kernel might be running on a 64-bit processor. But
1926 * if we're on a 32-bit processor and an i-cache incoherency
1927 * or race makes us see a 64-bit instruction here the sdl/sdr
1928 * would blow up, so for now we don't handle unaligned 64-bit
1929 * instructions on 32-bit kernels.
1930 */
1931 if (!access_ok(VERIFY_WRITE, addr, 8))
1932 goto sigbus;
1933
1934 value = regs->regs[reg];
1935 StoreDW(addr, value, res);
1936 if (res)
1937 goto fault;
1938 goto success;
1939#endif /* CONFIG_64BIT */
1940
1941 /* Cannot handle 64-bit instructions in 32-bit kernel */
1942 goto sigill;
1943
1944success:
1945 regs->cp0_epc = contpc; /* advance or branch */
1946
1947#ifdef CONFIG_DEBUG_FS
1948 unaligned_instructions++;
1949#endif
1950 return;
1951
1952fault:
1953 /* roll back jump/branch */
1954 regs->cp0_epc = origpc;
1955 regs->regs[31] = orig31;
1956 /* Did we have an exception handler installed? */
1957 if (fixup_exception(regs))
1958 return;
1959
1960 die_if_kernel("Unhandled kernel unaligned access", regs);
1961 force_sig(SIGSEGV, current);
1962
1963 return;
1964
1965sigbus:
1966 die_if_kernel("Unhandled kernel unaligned access", regs);
1967 force_sig(SIGBUS, current);
1968
1969 return;
1970
1971sigill:
1972 die_if_kernel
1973 ("Unhandled kernel unaligned access or invalid instruction", regs);
1974 force_sig(SIGILL, current);
1975}
1976
1977static void emulate_load_store_MIPS16e(struct pt_regs *regs, void __user * addr)
1978{
1979 unsigned long value;
1980 unsigned int res;
1981 int reg;
1982 unsigned long orig31;
1983 u16 __user *pc16;
1984 unsigned long origpc;
1985 union mips16e_instruction mips16inst, oldinst;
1986
1987 origpc = regs->cp0_epc;
1988 orig31 = regs->regs[31];
1989 pc16 = (unsigned short __user *)msk_isa16_mode(origpc);
1990 /*
1991 * This load never faults.
1992 */
1993 __get_user(mips16inst.full, pc16);
1994 oldinst = mips16inst;
1995
1996 /* skip EXTEND instruction */
1997 if (mips16inst.ri.opcode == MIPS16e_extend_op) {
1998 pc16++;
1999 __get_user(mips16inst.full, pc16);
2000 } else if (delay_slot(regs)) {
2001 /* skip jump instructions */
2002 /* JAL/JALX are 32 bits but have OPCODE in first short int */
2003 if (mips16inst.ri.opcode == MIPS16e_jal_op)
2004 pc16++;
2005 pc16++;
2006 if (get_user(mips16inst.full, pc16))
2007 goto sigbus;
2008 }
2009
2010 switch (mips16inst.ri.opcode) {
2011 case MIPS16e_i64_op: /* I64 or RI64 instruction */
2012 switch (mips16inst.i64.func) { /* I64/RI64 func field check */
2013 case MIPS16e_ldpc_func:
2014 case MIPS16e_ldsp_func:
2015 reg = reg16to32[mips16inst.ri64.ry];
2016 goto loadDW;
2017
2018 case MIPS16e_sdsp_func:
2019 reg = reg16to32[mips16inst.ri64.ry];
2020 goto writeDW;
2021
2022 case MIPS16e_sdrasp_func:
2023 reg = 29; /* GPRSP */
2024 goto writeDW;
2025 }
2026
2027 goto sigbus;
2028
2029 case MIPS16e_swsp_op:
2030 case MIPS16e_lwpc_op:
2031 case MIPS16e_lwsp_op:
2032 reg = reg16to32[mips16inst.ri.rx];
2033 break;
2034
2035 case MIPS16e_i8_op:
2036 if (mips16inst.i8.func != MIPS16e_swrasp_func)
2037 goto sigbus;
2038 reg = 29; /* GPRSP */
2039 break;
2040
2041 default:
2042 reg = reg16to32[mips16inst.rri.ry];
2043 break;
2044 }
2045
2046 switch (mips16inst.ri.opcode) {
2047
2048 case MIPS16e_lb_op:
2049 case MIPS16e_lbu_op:
2050 case MIPS16e_sb_op:
2051 goto sigbus;
2052
2053 case MIPS16e_lh_op:
2054 if (!access_ok(VERIFY_READ, addr, 2))
2055 goto sigbus;
2056
2057 LoadHW(addr, value, res);
2058 if (res)
2059 goto fault;
2060 MIPS16e_compute_return_epc(regs, &oldinst);
2061 regs->regs[reg] = value;
2062 break;
2063
2064 case MIPS16e_lhu_op:
2065 if (!access_ok(VERIFY_READ, addr, 2))
2066 goto sigbus;
2067
2068 LoadHWU(addr, value, res);
2069 if (res)
2070 goto fault;
2071 MIPS16e_compute_return_epc(regs, &oldinst);
2072 regs->regs[reg] = value;
2073 break;
2074
2075 case MIPS16e_lw_op:
2076 case MIPS16e_lwpc_op:
2077 case MIPS16e_lwsp_op:
2078 if (!access_ok(VERIFY_READ, addr, 4))
2079 goto sigbus;
2080
2081 LoadW(addr, value, res);
2082 if (res)
2083 goto fault;
2084 MIPS16e_compute_return_epc(regs, &oldinst);
2085 regs->regs[reg] = value;
2086 break;
2087
2088 case MIPS16e_lwu_op:
2089#ifdef CONFIG_64BIT
2090 /*
2091 * A 32-bit kernel might be running on a 64-bit processor. But
2092 * if we're on a 32-bit processor and an i-cache incoherency
2093 * or race makes us see a 64-bit instruction here the sdl/sdr
2094 * would blow up, so for now we don't handle unaligned 64-bit
2095 * instructions on 32-bit kernels.
2096 */
2097 if (!access_ok(VERIFY_READ, addr, 4))
2098 goto sigbus;
2099
2100 LoadWU(addr, value, res);
2101 if (res)
2102 goto fault;
2103 MIPS16e_compute_return_epc(regs, &oldinst);
2104 regs->regs[reg] = value;
2105 break;
2106#endif /* CONFIG_64BIT */
2107
2108 /* Cannot handle 64-bit instructions in 32-bit kernel */
2109 goto sigill;
2110
2111 case MIPS16e_ld_op:
2112loadDW:
2113#ifdef CONFIG_64BIT
2114 /*
2115 * A 32-bit kernel might be running on a 64-bit processor. But
2116 * if we're on a 32-bit processor and an i-cache incoherency
2117 * or race makes us see a 64-bit instruction here the sdl/sdr
2118 * would blow up, so for now we don't handle unaligned 64-bit
2119 * instructions on 32-bit kernels.
2120 */
2121 if (!access_ok(VERIFY_READ, addr, 8))
2122 goto sigbus;
2123
2124 LoadDW(addr, value, res);
2125 if (res)
2126 goto fault;
2127 MIPS16e_compute_return_epc(regs, &oldinst);
2128 regs->regs[reg] = value;
2129 break;
2130#endif /* CONFIG_64BIT */
2131
2132 /* Cannot handle 64-bit instructions in 32-bit kernel */
2133 goto sigill;
2134
2135 case MIPS16e_sh_op:
2136 if (!access_ok(VERIFY_WRITE, addr, 2))
2137 goto sigbus;
2138
2139 MIPS16e_compute_return_epc(regs, &oldinst);
2140 value = regs->regs[reg];
2141 StoreHW(addr, value, res);
2142 if (res)
2143 goto fault;
2144 break;
2145
2146 case MIPS16e_sw_op:
2147 case MIPS16e_swsp_op:
2148 case MIPS16e_i8_op: /* actually - MIPS16e_swrasp_func */
2149 if (!access_ok(VERIFY_WRITE, addr, 4))
2150 goto sigbus;
2151
2152 MIPS16e_compute_return_epc(regs, &oldinst);
2153 value = regs->regs[reg];
2154 StoreW(addr, value, res);
2155 if (res)
2156 goto fault;
2157 break;
2158
2159 case MIPS16e_sd_op:
2160writeDW:
2161#ifdef CONFIG_64BIT
2162 /*
2163 * A 32-bit kernel might be running on a 64-bit processor. But
2164 * if we're on a 32-bit processor and an i-cache incoherency
2165 * or race makes us see a 64-bit instruction here the sdl/sdr
2166 * would blow up, so for now we don't handle unaligned 64-bit
2167 * instructions on 32-bit kernels.
2168 */
2169 if (!access_ok(VERIFY_WRITE, addr, 8))
2170 goto sigbus;
2171
2172 MIPS16e_compute_return_epc(regs, &oldinst);
2173 value = regs->regs[reg];
2174 StoreDW(addr, value, res);
2175 if (res)
2176 goto fault;
2177 break;
2178#endif /* CONFIG_64BIT */
2179
2180 /* Cannot handle 64-bit instructions in 32-bit kernel */
2181 goto sigill;
2182
2183 default:
2184 /*
2185 * Pheeee... We encountered an yet unknown instruction or
2186 * cache coherence problem. Die sucker, die ...
2187 */
2188 goto sigill;
2189 }
2190
2191#ifdef CONFIG_DEBUG_FS
2192 unaligned_instructions++;
2193#endif
2194
2195 return;
2196
2197fault:
2198 /* roll back jump/branch */
2199 regs->cp0_epc = origpc;
2200 regs->regs[31] = orig31;
2201 /* Did we have an exception handler installed? */
2202 if (fixup_exception(regs))
2203 return;
2204
2205 die_if_kernel("Unhandled kernel unaligned access", regs);
2206 force_sig(SIGSEGV, current);
2207
2208 return;
2209
2210sigbus:
2211 die_if_kernel("Unhandled kernel unaligned access", regs);
2212 force_sig(SIGBUS, current);
2213
2214 return;
2215
2216sigill:
2217 die_if_kernel
2218 ("Unhandled kernel unaligned access or invalid instruction", regs);
2219 force_sig(SIGILL, current);
2220}
2221
2222asmlinkage void do_ade(struct pt_regs *regs)
2223{
2224 enum ctx_state prev_state;
2225 unsigned int __user *pc;
2226 mm_segment_t seg;
2227
2228 prev_state = exception_enter();
2229 perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS,
2230 1, regs, regs->cp0_badvaddr);
2231 /*
2232 * Did we catch a fault trying to load an instruction?
2233 */
2234 if (regs->cp0_badvaddr == regs->cp0_epc)
2235 goto sigbus;
2236
2237 if (user_mode(regs) && !test_thread_flag(TIF_FIXADE))
2238 goto sigbus;
2239 if (unaligned_action == UNALIGNED_ACTION_SIGNAL)
2240 goto sigbus;
2241
2242 /*
2243 * Do branch emulation only if we didn't forward the exception.
2244 * This is all so but ugly ...
2245 */
2246
2247 /*
2248 * Are we running in microMIPS mode?
2249 */
2250 if (get_isa16_mode(regs->cp0_epc)) {
2251 /*
2252 * Did we catch a fault trying to load an instruction in
2253 * 16-bit mode?
2254 */
2255 if (regs->cp0_badvaddr == msk_isa16_mode(regs->cp0_epc))
2256 goto sigbus;
2257 if (unaligned_action == UNALIGNED_ACTION_SHOW)
2258 show_registers(regs);
2259
2260 if (cpu_has_mmips) {
2261 seg = get_fs();
2262 if (!user_mode(regs))
2263 set_fs(KERNEL_DS);
2264 emulate_load_store_microMIPS(regs,
2265 (void __user *)regs->cp0_badvaddr);
2266 set_fs(seg);
2267
2268 return;
2269 }
2270
2271 if (cpu_has_mips16) {
2272 seg = get_fs();
2273 if (!user_mode(regs))
2274 set_fs(KERNEL_DS);
2275 emulate_load_store_MIPS16e(regs,
2276 (void __user *)regs->cp0_badvaddr);
2277 set_fs(seg);
2278
2279 return;
2280 }
2281
2282 goto sigbus;
2283 }
2284
2285 if (unaligned_action == UNALIGNED_ACTION_SHOW)
2286 show_registers(regs);
2287 pc = (unsigned int __user *)exception_epc(regs);
2288
2289 seg = get_fs();
2290 if (!user_mode(regs))
2291 set_fs(KERNEL_DS);
2292 emulate_load_store_insn(regs, (void __user *)regs->cp0_badvaddr, pc);
2293 set_fs(seg);
2294
2295 return;
2296
2297sigbus:
2298 die_if_kernel("Kernel unaligned instruction access", regs);
2299 force_sig(SIGBUS, current);
2300
2301 /*
2302 * XXX On return from the signal handler we should advance the epc
2303 */
2304 exception_exit(prev_state);
2305}
2306
2307#ifdef CONFIG_DEBUG_FS
2308static int __init debugfs_unaligned(void)
2309{
2310 struct dentry *d;
2311
2312 if (!mips_debugfs_dir)
2313 return -ENODEV;
2314 d = debugfs_create_u32("unaligned_instructions", S_IRUGO,
2315 mips_debugfs_dir, &unaligned_instructions);
2316 if (!d)
2317 return -ENOMEM;
2318 d = debugfs_create_u32("unaligned_action", S_IRUGO | S_IWUSR,
2319 mips_debugfs_dir, &unaligned_action);
2320 if (!d)
2321 return -ENOMEM;
2322 return 0;
2323}
2324arch_initcall(debugfs_unaligned);
2325#endif