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