1 /*
2 * arch/sh/kernel/traps_64.c
3 *
4 * Copyright (C) 2000, 2001 Paolo Alberelli
5 * Copyright (C) 2003, 2004 Paul Mundt
6 * Copyright (C) 2003, 2004 Richard Curnow
7 *
8 * This file is subject to the terms and conditions of the GNU General Public
9 * License. See the file "COPYING" in the main directory of this archive
10 * for more details.
11 */
12 #include <linux/sched.h>
13 #include <linux/kernel.h>
14 #include <linux/string.h>
15 #include <linux/errno.h>
16 #include <linux/ptrace.h>
17 #include <linux/timer.h>
18 #include <linux/mm.h>
19 #include <linux/smp.h>
20 #include <linux/init.h>
21 #include <linux/delay.h>
22 #include <linux/spinlock.h>
23 #include <linux/kallsyms.h>
24 #include <linux/interrupt.h>
25 #include <linux/sysctl.h>
26 #include <linux/module.h>
27 #include <asm/system.h>
28 #include <asm/uaccess.h>
29 #include <asm/io.h>
30 #include <asm/atomic.h>
31 #include <asm/processor.h>
32 #include <asm/pgtable.h>
33 #include <asm/fpu.h>
34
35 #undef DEBUG_EXCEPTION
36 #ifdef DEBUG_EXCEPTION
37 /* implemented in ../lib/dbg.c */
38 extern void show_excp_regs(char *fname, int trapnr, int signr,
39 struct pt_regs *regs);
40 #else
41 #define show_excp_regs(a, b, c, d)
42 #endif
43
44 static void do_unhandled_exception(int trapnr, int signr, char *str, char *fn_name,
45 unsigned long error_code, struct pt_regs *regs, struct task_struct *tsk);
46
47 #define DO_ERROR(trapnr, signr, str, name, tsk) \
48 asmlinkage void do_##name(unsigned long error_code, struct pt_regs *regs) \
49 { \
50 do_unhandled_exception(trapnr, signr, str, __stringify(name), error_code, regs, current); \
51 }
52
53 spinlock_t die_lock;
54
die(const char * str,struct pt_regs * regs,long err)55 void die(const char * str, struct pt_regs * regs, long err)
56 {
57 console_verbose();
58 spin_lock_irq(&die_lock);
59 printk("%s: %lx\n", str, (err & 0xffffff));
60 show_regs(regs);
61 spin_unlock_irq(&die_lock);
62 do_exit(SIGSEGV);
63 }
64
die_if_kernel(const char * str,struct pt_regs * regs,long err)65 static inline void die_if_kernel(const char * str, struct pt_regs * regs, long err)
66 {
67 if (!user_mode(regs))
68 die(str, regs, err);
69 }
70
die_if_no_fixup(const char * str,struct pt_regs * regs,long err)71 static void die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
72 {
73 if (!user_mode(regs)) {
74 const struct exception_table_entry *fixup;
75 fixup = search_exception_tables(regs->pc);
76 if (fixup) {
77 regs->pc = fixup->fixup;
78 return;
79 }
80 die(str, regs, err);
81 }
82 }
83
84 DO_ERROR(13, SIGILL, "illegal slot instruction", illegal_slot_inst, current)
85 DO_ERROR(87, SIGSEGV, "address error (exec)", address_error_exec, current)
86
87
88 /* Implement misaligned load/store handling for kernel (and optionally for user
89 mode too). Limitation : only SHmedia mode code is handled - there is no
90 handling at all for misaligned accesses occurring in SHcompact code yet. */
91
92 static int misaligned_fixup(struct pt_regs *regs);
93
do_address_error_load(unsigned long error_code,struct pt_regs * regs)94 asmlinkage void do_address_error_load(unsigned long error_code, struct pt_regs *regs)
95 {
96 if (misaligned_fixup(regs) < 0) {
97 do_unhandled_exception(7, SIGSEGV, "address error(load)",
98 "do_address_error_load",
99 error_code, regs, current);
100 }
101 return;
102 }
103
do_address_error_store(unsigned long error_code,struct pt_regs * regs)104 asmlinkage void do_address_error_store(unsigned long error_code, struct pt_regs *regs)
105 {
106 if (misaligned_fixup(regs) < 0) {
107 do_unhandled_exception(8, SIGSEGV, "address error(store)",
108 "do_address_error_store",
109 error_code, regs, current);
110 }
111 return;
112 }
113
114 #if defined(CONFIG_SH64_ID2815_WORKAROUND)
115
116 #define OPCODE_INVALID 0
117 #define OPCODE_USER_VALID 1
118 #define OPCODE_PRIV_VALID 2
119
120 /* getcon/putcon - requires checking which control register is referenced. */
121 #define OPCODE_CTRL_REG 3
122
123 /* Table of valid opcodes for SHmedia mode.
124 Form a 10-bit value by concatenating the major/minor opcodes i.e.
125 opcode[31:26,20:16]. The 6 MSBs of this value index into the following
126 array. The 4 LSBs select the bit-pair in the entry (bits 1:0 correspond to
127 LSBs==4'b0000 etc). */
128 static unsigned long shmedia_opcode_table[64] = {
129 0x55554044,0x54445055,0x15141514,0x14541414,0x00000000,0x10001000,0x01110055,0x04050015,
130 0x00000444,0xc0000000,0x44545515,0x40405555,0x55550015,0x10005555,0x55555505,0x04050000,
131 0x00000555,0x00000404,0x00040445,0x15151414,0x00000000,0x00000000,0x00000000,0x00000000,
132 0x00000055,0x40404444,0x00000404,0xc0009495,0x00000000,0x00000000,0x00000000,0x00000000,
133 0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
134 0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
135 0x80005050,0x04005055,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,0x55555555,
136 0x81055554,0x00000404,0x55555555,0x55555555,0x00000000,0x00000000,0x00000000,0x00000000
137 };
138
do_reserved_inst(unsigned long error_code,struct pt_regs * regs)139 void do_reserved_inst(unsigned long error_code, struct pt_regs *regs)
140 {
141 /* Workaround SH5-101 cut2 silicon defect #2815 :
142 in some situations, inter-mode branches from SHcompact -> SHmedia
143 which should take ITLBMISS or EXECPROT exceptions at the target
144 falsely take RESINST at the target instead. */
145
146 unsigned long opcode = 0x6ff4fff0; /* guaranteed reserved opcode */
147 unsigned long pc, aligned_pc;
148 int get_user_error;
149 int trapnr = 12;
150 int signr = SIGILL;
151 char *exception_name = "reserved_instruction";
152
153 pc = regs->pc;
154 if ((pc & 3) == 1) {
155 /* SHmedia : check for defect. This requires executable vmas
156 to be readable too. */
157 aligned_pc = pc & ~3;
158 if (!access_ok(VERIFY_READ, aligned_pc, sizeof(unsigned long))) {
159 get_user_error = -EFAULT;
160 } else {
161 get_user_error = __get_user(opcode, (unsigned long *)aligned_pc);
162 }
163 if (get_user_error >= 0) {
164 unsigned long index, shift;
165 unsigned long major, minor, combined;
166 unsigned long reserved_field;
167 reserved_field = opcode & 0xf; /* These bits are currently reserved as zero in all valid opcodes */
168 major = (opcode >> 26) & 0x3f;
169 minor = (opcode >> 16) & 0xf;
170 combined = (major << 4) | minor;
171 index = major;
172 shift = minor << 1;
173 if (reserved_field == 0) {
174 int opcode_state = (shmedia_opcode_table[index] >> shift) & 0x3;
175 switch (opcode_state) {
176 case OPCODE_INVALID:
177 /* Trap. */
178 break;
179 case OPCODE_USER_VALID:
180 /* Restart the instruction : the branch to the instruction will now be from an RTE
181 not from SHcompact so the silicon defect won't be triggered. */
182 return;
183 case OPCODE_PRIV_VALID:
184 if (!user_mode(regs)) {
185 /* Should only ever get here if a module has
186 SHcompact code inside it. If so, the same fix up is needed. */
187 return; /* same reason */
188 }
189 /* Otherwise, user mode trying to execute a privileged instruction -
190 fall through to trap. */
191 break;
192 case OPCODE_CTRL_REG:
193 /* If in privileged mode, return as above. */
194 if (!user_mode(regs)) return;
195 /* In user mode ... */
196 if (combined == 0x9f) { /* GETCON */
197 unsigned long regno = (opcode >> 20) & 0x3f;
198 if (regno >= 62) {
199 return;
200 }
201 /* Otherwise, reserved or privileged control register, => trap */
202 } else if (combined == 0x1bf) { /* PUTCON */
203 unsigned long regno = (opcode >> 4) & 0x3f;
204 if (regno >= 62) {
205 return;
206 }
207 /* Otherwise, reserved or privileged control register, => trap */
208 } else {
209 /* Trap */
210 }
211 break;
212 default:
213 /* Fall through to trap. */
214 break;
215 }
216 }
217 /* fall through to normal resinst processing */
218 } else {
219 /* Error trying to read opcode. This typically means a
220 real fault, not a RESINST any more. So change the
221 codes. */
222 trapnr = 87;
223 exception_name = "address error (exec)";
224 signr = SIGSEGV;
225 }
226 }
227
228 do_unhandled_exception(trapnr, signr, exception_name, "do_reserved_inst", error_code, regs, current);
229 }
230
231 #else /* CONFIG_SH64_ID2815_WORKAROUND */
232
233 /* If the workaround isn't needed, this is just a straightforward reserved
234 instruction */
235 DO_ERROR(12, SIGILL, "reserved instruction", reserved_inst, current)
236
237 #endif /* CONFIG_SH64_ID2815_WORKAROUND */
238
239 /* Called with interrupts disabled */
do_exception_error(unsigned long ex,struct pt_regs * regs)240 asmlinkage void do_exception_error(unsigned long ex, struct pt_regs *regs)
241 {
242 show_excp_regs(__func__, -1, -1, regs);
243 die_if_kernel("exception", regs, ex);
244 }
245
do_unknown_trapa(unsigned long scId,struct pt_regs * regs)246 int do_unknown_trapa(unsigned long scId, struct pt_regs *regs)
247 {
248 /* Syscall debug */
249 printk("System call ID error: [0x1#args:8 #syscall:16 0x%lx]\n", scId);
250
251 die_if_kernel("unknown trapa", regs, scId);
252
253 return -ENOSYS;
254 }
255
show_stack(struct task_struct * tsk,unsigned long * sp)256 void show_stack(struct task_struct *tsk, unsigned long *sp)
257 {
258 #ifdef CONFIG_KALLSYMS
259 extern void sh64_unwind(struct pt_regs *regs);
260 struct pt_regs *regs;
261
262 regs = tsk ? tsk->thread.kregs : NULL;
263
264 sh64_unwind(regs);
265 #else
266 printk(KERN_ERR "Can't backtrace on sh64 without CONFIG_KALLSYMS\n");
267 #endif
268 }
269
show_task(unsigned long * sp)270 void show_task(unsigned long *sp)
271 {
272 show_stack(NULL, sp);
273 }
274
dump_stack(void)275 void dump_stack(void)
276 {
277 show_task(NULL);
278 }
279 /* Needed by any user of WARN_ON in view of the defn in include/asm-sh/bug.h */
280 EXPORT_SYMBOL(dump_stack);
281
do_unhandled_exception(int trapnr,int signr,char * str,char * fn_name,unsigned long error_code,struct pt_regs * regs,struct task_struct * tsk)282 static void do_unhandled_exception(int trapnr, int signr, char *str, char *fn_name,
283 unsigned long error_code, struct pt_regs *regs, struct task_struct *tsk)
284 {
285 show_excp_regs(fn_name, trapnr, signr, regs);
286 tsk->thread.error_code = error_code;
287 tsk->thread.trap_no = trapnr;
288
289 if (user_mode(regs))
290 force_sig(signr, tsk);
291
292 die_if_no_fixup(str, regs, error_code);
293 }
294
read_opcode(unsigned long long pc,unsigned long * result_opcode,int from_user_mode)295 static int read_opcode(unsigned long long pc, unsigned long *result_opcode, int from_user_mode)
296 {
297 int get_user_error;
298 unsigned long aligned_pc;
299 unsigned long opcode;
300
301 if ((pc & 3) == 1) {
302 /* SHmedia */
303 aligned_pc = pc & ~3;
304 if (from_user_mode) {
305 if (!access_ok(VERIFY_READ, aligned_pc, sizeof(unsigned long))) {
306 get_user_error = -EFAULT;
307 } else {
308 get_user_error = __get_user(opcode, (unsigned long *)aligned_pc);
309 *result_opcode = opcode;
310 }
311 return get_user_error;
312 } else {
313 /* If the fault was in the kernel, we can either read
314 * this directly, or if not, we fault.
315 */
316 *result_opcode = *(unsigned long *) aligned_pc;
317 return 0;
318 }
319 } else if ((pc & 1) == 0) {
320 /* SHcompact */
321 /* TODO : provide handling for this. We don't really support
322 user-mode SHcompact yet, and for a kernel fault, this would
323 have to come from a module built for SHcompact. */
324 return -EFAULT;
325 } else {
326 /* misaligned */
327 return -EFAULT;
328 }
329 }
330
address_is_sign_extended(__u64 a)331 static int address_is_sign_extended(__u64 a)
332 {
333 __u64 b;
334 #if (NEFF == 32)
335 b = (__u64)(__s64)(__s32)(a & 0xffffffffUL);
336 return (b == a) ? 1 : 0;
337 #else
338 #error "Sign extend check only works for NEFF==32"
339 #endif
340 }
341
generate_and_check_address(struct pt_regs * regs,__u32 opcode,int displacement_not_indexed,int width_shift,__u64 * address)342 static int generate_and_check_address(struct pt_regs *regs,
343 __u32 opcode,
344 int displacement_not_indexed,
345 int width_shift,
346 __u64 *address)
347 {
348 /* return -1 for fault, 0 for OK */
349
350 __u64 base_address, addr;
351 int basereg;
352
353 basereg = (opcode >> 20) & 0x3f;
354 base_address = regs->regs[basereg];
355 if (displacement_not_indexed) {
356 __s64 displacement;
357 displacement = (opcode >> 10) & 0x3ff;
358 displacement = ((displacement << 54) >> 54); /* sign extend */
359 addr = (__u64)((__s64)base_address + (displacement << width_shift));
360 } else {
361 __u64 offset;
362 int offsetreg;
363 offsetreg = (opcode >> 10) & 0x3f;
364 offset = regs->regs[offsetreg];
365 addr = base_address + offset;
366 }
367
368 /* Check sign extended */
369 if (!address_is_sign_extended(addr)) {
370 return -1;
371 }
372
373 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
374 /* Check accessible. For misaligned access in the kernel, assume the
375 address is always accessible (and if not, just fault when the
376 load/store gets done.) */
377 if (user_mode(regs)) {
378 if (addr >= TASK_SIZE) {
379 return -1;
380 }
381 /* Do access_ok check later - it depends on whether it's a load or a store. */
382 }
383 #endif
384
385 *address = addr;
386 return 0;
387 }
388
389 /* Default value as for sh */
390 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
391 static int user_mode_unaligned_fixup_count = 10;
392 static int user_mode_unaligned_fixup_enable = 1;
393 #endif
394
395 static int kernel_mode_unaligned_fixup_count = 32;
396
misaligned_kernel_word_load(__u64 address,int do_sign_extend,__u64 * result)397 static void misaligned_kernel_word_load(__u64 address, int do_sign_extend, __u64 *result)
398 {
399 unsigned short x;
400 unsigned char *p, *q;
401 p = (unsigned char *) (int) address;
402 q = (unsigned char *) &x;
403 q[0] = p[0];
404 q[1] = p[1];
405
406 if (do_sign_extend) {
407 *result = (__u64)(__s64) *(short *) &x;
408 } else {
409 *result = (__u64) x;
410 }
411 }
412
misaligned_kernel_word_store(__u64 address,__u64 value)413 static void misaligned_kernel_word_store(__u64 address, __u64 value)
414 {
415 unsigned short x;
416 unsigned char *p, *q;
417 p = (unsigned char *) (int) address;
418 q = (unsigned char *) &x;
419
420 x = (__u16) value;
421 p[0] = q[0];
422 p[1] = q[1];
423 }
424
misaligned_load(struct pt_regs * regs,__u32 opcode,int displacement_not_indexed,int width_shift,int do_sign_extend)425 static int misaligned_load(struct pt_regs *regs,
426 __u32 opcode,
427 int displacement_not_indexed,
428 int width_shift,
429 int do_sign_extend)
430 {
431 /* Return -1 for a fault, 0 for OK */
432 int error;
433 int destreg;
434 __u64 address;
435
436 error = generate_and_check_address(regs, opcode,
437 displacement_not_indexed, width_shift, &address);
438 if (error < 0) {
439 return error;
440 }
441
442 destreg = (opcode >> 4) & 0x3f;
443 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
444 if (user_mode(regs)) {
445 __u64 buffer;
446
447 if (!access_ok(VERIFY_READ, (unsigned long) address, 1UL<<width_shift)) {
448 return -1;
449 }
450
451 if (__copy_user(&buffer, (const void *)(int)address, (1 << width_shift)) > 0) {
452 return -1; /* fault */
453 }
454 switch (width_shift) {
455 case 1:
456 if (do_sign_extend) {
457 regs->regs[destreg] = (__u64)(__s64) *(__s16 *) &buffer;
458 } else {
459 regs->regs[destreg] = (__u64) *(__u16 *) &buffer;
460 }
461 break;
462 case 2:
463 regs->regs[destreg] = (__u64)(__s64) *(__s32 *) &buffer;
464 break;
465 case 3:
466 regs->regs[destreg] = buffer;
467 break;
468 default:
469 printk("Unexpected width_shift %d in misaligned_load, PC=%08lx\n",
470 width_shift, (unsigned long) regs->pc);
471 break;
472 }
473 } else
474 #endif
475 {
476 /* kernel mode - we can take short cuts since if we fault, it's a genuine bug */
477 __u64 lo, hi;
478
479 switch (width_shift) {
480 case 1:
481 misaligned_kernel_word_load(address, do_sign_extend, ®s->regs[destreg]);
482 break;
483 case 2:
484 asm ("ldlo.l %1, 0, %0" : "=r" (lo) : "r" (address));
485 asm ("ldhi.l %1, 3, %0" : "=r" (hi) : "r" (address));
486 regs->regs[destreg] = lo | hi;
487 break;
488 case 3:
489 asm ("ldlo.q %1, 0, %0" : "=r" (lo) : "r" (address));
490 asm ("ldhi.q %1, 7, %0" : "=r" (hi) : "r" (address));
491 regs->regs[destreg] = lo | hi;
492 break;
493
494 default:
495 printk("Unexpected width_shift %d in misaligned_load, PC=%08lx\n",
496 width_shift, (unsigned long) regs->pc);
497 break;
498 }
499 }
500
501 return 0;
502
503 }
504
misaligned_store(struct pt_regs * regs,__u32 opcode,int displacement_not_indexed,int width_shift)505 static int misaligned_store(struct pt_regs *regs,
506 __u32 opcode,
507 int displacement_not_indexed,
508 int width_shift)
509 {
510 /* Return -1 for a fault, 0 for OK */
511 int error;
512 int srcreg;
513 __u64 address;
514
515 error = generate_and_check_address(regs, opcode,
516 displacement_not_indexed, width_shift, &address);
517 if (error < 0) {
518 return error;
519 }
520
521 srcreg = (opcode >> 4) & 0x3f;
522 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
523 if (user_mode(regs)) {
524 __u64 buffer;
525
526 if (!access_ok(VERIFY_WRITE, (unsigned long) address, 1UL<<width_shift)) {
527 return -1;
528 }
529
530 switch (width_shift) {
531 case 1:
532 *(__u16 *) &buffer = (__u16) regs->regs[srcreg];
533 break;
534 case 2:
535 *(__u32 *) &buffer = (__u32) regs->regs[srcreg];
536 break;
537 case 3:
538 buffer = regs->regs[srcreg];
539 break;
540 default:
541 printk("Unexpected width_shift %d in misaligned_store, PC=%08lx\n",
542 width_shift, (unsigned long) regs->pc);
543 break;
544 }
545
546 if (__copy_user((void *)(int)address, &buffer, (1 << width_shift)) > 0) {
547 return -1; /* fault */
548 }
549 } else
550 #endif
551 {
552 /* kernel mode - we can take short cuts since if we fault, it's a genuine bug */
553 __u64 val = regs->regs[srcreg];
554
555 switch (width_shift) {
556 case 1:
557 misaligned_kernel_word_store(address, val);
558 break;
559 case 2:
560 asm ("stlo.l %1, 0, %0" : : "r" (val), "r" (address));
561 asm ("sthi.l %1, 3, %0" : : "r" (val), "r" (address));
562 break;
563 case 3:
564 asm ("stlo.q %1, 0, %0" : : "r" (val), "r" (address));
565 asm ("sthi.q %1, 7, %0" : : "r" (val), "r" (address));
566 break;
567
568 default:
569 printk("Unexpected width_shift %d in misaligned_store, PC=%08lx\n",
570 width_shift, (unsigned long) regs->pc);
571 break;
572 }
573 }
574
575 return 0;
576
577 }
578
579 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
580 /* Never need to fix up misaligned FPU accesses within the kernel since that's a real
581 error. */
misaligned_fpu_load(struct pt_regs * regs,__u32 opcode,int displacement_not_indexed,int width_shift,int do_paired_load)582 static int misaligned_fpu_load(struct pt_regs *regs,
583 __u32 opcode,
584 int displacement_not_indexed,
585 int width_shift,
586 int do_paired_load)
587 {
588 /* Return -1 for a fault, 0 for OK */
589 int error;
590 int destreg;
591 __u64 address;
592
593 error = generate_and_check_address(regs, opcode,
594 displacement_not_indexed, width_shift, &address);
595 if (error < 0) {
596 return error;
597 }
598
599 destreg = (opcode >> 4) & 0x3f;
600 if (user_mode(regs)) {
601 __u64 buffer;
602 __u32 buflo, bufhi;
603
604 if (!access_ok(VERIFY_READ, (unsigned long) address, 1UL<<width_shift)) {
605 return -1;
606 }
607
608 if (__copy_user(&buffer, (const void *)(int)address, (1 << width_shift)) > 0) {
609 return -1; /* fault */
610 }
611 /* 'current' may be the current owner of the FPU state, so
612 context switch the registers into memory so they can be
613 indexed by register number. */
614 if (last_task_used_math == current) {
615 enable_fpu();
616 save_fpu(current, regs);
617 disable_fpu();
618 last_task_used_math = NULL;
619 regs->sr |= SR_FD;
620 }
621
622 buflo = *(__u32*) &buffer;
623 bufhi = *(1 + (__u32*) &buffer);
624
625 switch (width_shift) {
626 case 2:
627 current->thread.fpu.hard.fp_regs[destreg] = buflo;
628 break;
629 case 3:
630 if (do_paired_load) {
631 current->thread.fpu.hard.fp_regs[destreg] = buflo;
632 current->thread.fpu.hard.fp_regs[destreg+1] = bufhi;
633 } else {
634 #if defined(CONFIG_CPU_LITTLE_ENDIAN)
635 current->thread.fpu.hard.fp_regs[destreg] = bufhi;
636 current->thread.fpu.hard.fp_regs[destreg+1] = buflo;
637 #else
638 current->thread.fpu.hard.fp_regs[destreg] = buflo;
639 current->thread.fpu.hard.fp_regs[destreg+1] = bufhi;
640 #endif
641 }
642 break;
643 default:
644 printk("Unexpected width_shift %d in misaligned_fpu_load, PC=%08lx\n",
645 width_shift, (unsigned long) regs->pc);
646 break;
647 }
648 return 0;
649 } else {
650 die ("Misaligned FPU load inside kernel", regs, 0);
651 return -1;
652 }
653
654
655 }
656
misaligned_fpu_store(struct pt_regs * regs,__u32 opcode,int displacement_not_indexed,int width_shift,int do_paired_load)657 static int misaligned_fpu_store(struct pt_regs *regs,
658 __u32 opcode,
659 int displacement_not_indexed,
660 int width_shift,
661 int do_paired_load)
662 {
663 /* Return -1 for a fault, 0 for OK */
664 int error;
665 int srcreg;
666 __u64 address;
667
668 error = generate_and_check_address(regs, opcode,
669 displacement_not_indexed, width_shift, &address);
670 if (error < 0) {
671 return error;
672 }
673
674 srcreg = (opcode >> 4) & 0x3f;
675 if (user_mode(regs)) {
676 __u64 buffer;
677 /* Initialise these to NaNs. */
678 __u32 buflo=0xffffffffUL, bufhi=0xffffffffUL;
679
680 if (!access_ok(VERIFY_WRITE, (unsigned long) address, 1UL<<width_shift)) {
681 return -1;
682 }
683
684 /* 'current' may be the current owner of the FPU state, so
685 context switch the registers into memory so they can be
686 indexed by register number. */
687 if (last_task_used_math == current) {
688 enable_fpu();
689 save_fpu(current, regs);
690 disable_fpu();
691 last_task_used_math = NULL;
692 regs->sr |= SR_FD;
693 }
694
695 switch (width_shift) {
696 case 2:
697 buflo = current->thread.fpu.hard.fp_regs[srcreg];
698 break;
699 case 3:
700 if (do_paired_load) {
701 buflo = current->thread.fpu.hard.fp_regs[srcreg];
702 bufhi = current->thread.fpu.hard.fp_regs[srcreg+1];
703 } else {
704 #if defined(CONFIG_CPU_LITTLE_ENDIAN)
705 bufhi = current->thread.fpu.hard.fp_regs[srcreg];
706 buflo = current->thread.fpu.hard.fp_regs[srcreg+1];
707 #else
708 buflo = current->thread.fpu.hard.fp_regs[srcreg];
709 bufhi = current->thread.fpu.hard.fp_regs[srcreg+1];
710 #endif
711 }
712 break;
713 default:
714 printk("Unexpected width_shift %d in misaligned_fpu_store, PC=%08lx\n",
715 width_shift, (unsigned long) regs->pc);
716 break;
717 }
718
719 *(__u32*) &buffer = buflo;
720 *(1 + (__u32*) &buffer) = bufhi;
721 if (__copy_user((void *)(int)address, &buffer, (1 << width_shift)) > 0) {
722 return -1; /* fault */
723 }
724 return 0;
725 } else {
726 die ("Misaligned FPU load inside kernel", regs, 0);
727 return -1;
728 }
729 }
730 #endif
731
misaligned_fixup(struct pt_regs * regs)732 static int misaligned_fixup(struct pt_regs *regs)
733 {
734 unsigned long opcode;
735 int error;
736 int major, minor;
737
738 #if !defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
739 /* Never fixup user mode misaligned accesses without this option enabled. */
740 return -1;
741 #else
742 if (!user_mode_unaligned_fixup_enable) return -1;
743 #endif
744
745 error = read_opcode(regs->pc, &opcode, user_mode(regs));
746 if (error < 0) {
747 return error;
748 }
749 major = (opcode >> 26) & 0x3f;
750 minor = (opcode >> 16) & 0xf;
751
752 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
753 if (user_mode(regs) && (user_mode_unaligned_fixup_count > 0)) {
754 --user_mode_unaligned_fixup_count;
755 /* Only do 'count' worth of these reports, to remove a potential DoS against syslog */
756 printk("Fixing up unaligned userspace access in \"%s\" pid=%d pc=0x%08x ins=0x%08lx\n",
757 current->comm, task_pid_nr(current), (__u32)regs->pc, opcode);
758 } else
759 #endif
760 if (!user_mode(regs) && (kernel_mode_unaligned_fixup_count > 0)) {
761 --kernel_mode_unaligned_fixup_count;
762 if (in_interrupt()) {
763 printk("Fixing up unaligned kernelspace access in interrupt pc=0x%08x ins=0x%08lx\n",
764 (__u32)regs->pc, opcode);
765 } else {
766 printk("Fixing up unaligned kernelspace access in \"%s\" pid=%d pc=0x%08x ins=0x%08lx\n",
767 current->comm, task_pid_nr(current), (__u32)regs->pc, opcode);
768 }
769 }
770
771
772 switch (major) {
773 case (0x84>>2): /* LD.W */
774 error = misaligned_load(regs, opcode, 1, 1, 1);
775 break;
776 case (0xb0>>2): /* LD.UW */
777 error = misaligned_load(regs, opcode, 1, 1, 0);
778 break;
779 case (0x88>>2): /* LD.L */
780 error = misaligned_load(regs, opcode, 1, 2, 1);
781 break;
782 case (0x8c>>2): /* LD.Q */
783 error = misaligned_load(regs, opcode, 1, 3, 0);
784 break;
785
786 case (0xa4>>2): /* ST.W */
787 error = misaligned_store(regs, opcode, 1, 1);
788 break;
789 case (0xa8>>2): /* ST.L */
790 error = misaligned_store(regs, opcode, 1, 2);
791 break;
792 case (0xac>>2): /* ST.Q */
793 error = misaligned_store(regs, opcode, 1, 3);
794 break;
795
796 case (0x40>>2): /* indexed loads */
797 switch (minor) {
798 case 0x1: /* LDX.W */
799 error = misaligned_load(regs, opcode, 0, 1, 1);
800 break;
801 case 0x5: /* LDX.UW */
802 error = misaligned_load(regs, opcode, 0, 1, 0);
803 break;
804 case 0x2: /* LDX.L */
805 error = misaligned_load(regs, opcode, 0, 2, 1);
806 break;
807 case 0x3: /* LDX.Q */
808 error = misaligned_load(regs, opcode, 0, 3, 0);
809 break;
810 default:
811 error = -1;
812 break;
813 }
814 break;
815
816 case (0x60>>2): /* indexed stores */
817 switch (minor) {
818 case 0x1: /* STX.W */
819 error = misaligned_store(regs, opcode, 0, 1);
820 break;
821 case 0x2: /* STX.L */
822 error = misaligned_store(regs, opcode, 0, 2);
823 break;
824 case 0x3: /* STX.Q */
825 error = misaligned_store(regs, opcode, 0, 3);
826 break;
827 default:
828 error = -1;
829 break;
830 }
831 break;
832
833 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
834 case (0x94>>2): /* FLD.S */
835 error = misaligned_fpu_load(regs, opcode, 1, 2, 0);
836 break;
837 case (0x98>>2): /* FLD.P */
838 error = misaligned_fpu_load(regs, opcode, 1, 3, 1);
839 break;
840 case (0x9c>>2): /* FLD.D */
841 error = misaligned_fpu_load(regs, opcode, 1, 3, 0);
842 break;
843 case (0x1c>>2): /* floating indexed loads */
844 switch (minor) {
845 case 0x8: /* FLDX.S */
846 error = misaligned_fpu_load(regs, opcode, 0, 2, 0);
847 break;
848 case 0xd: /* FLDX.P */
849 error = misaligned_fpu_load(regs, opcode, 0, 3, 1);
850 break;
851 case 0x9: /* FLDX.D */
852 error = misaligned_fpu_load(regs, opcode, 0, 3, 0);
853 break;
854 default:
855 error = -1;
856 break;
857 }
858 break;
859 case (0xb4>>2): /* FLD.S */
860 error = misaligned_fpu_store(regs, opcode, 1, 2, 0);
861 break;
862 case (0xb8>>2): /* FLD.P */
863 error = misaligned_fpu_store(regs, opcode, 1, 3, 1);
864 break;
865 case (0xbc>>2): /* FLD.D */
866 error = misaligned_fpu_store(regs, opcode, 1, 3, 0);
867 break;
868 case (0x3c>>2): /* floating indexed stores */
869 switch (minor) {
870 case 0x8: /* FSTX.S */
871 error = misaligned_fpu_store(regs, opcode, 0, 2, 0);
872 break;
873 case 0xd: /* FSTX.P */
874 error = misaligned_fpu_store(regs, opcode, 0, 3, 1);
875 break;
876 case 0x9: /* FSTX.D */
877 error = misaligned_fpu_store(regs, opcode, 0, 3, 0);
878 break;
879 default:
880 error = -1;
881 break;
882 }
883 break;
884 #endif
885
886 default:
887 /* Fault */
888 error = -1;
889 break;
890 }
891
892 if (error < 0) {
893 return error;
894 } else {
895 regs->pc += 4; /* Skip the instruction that's just been emulated */
896 return 0;
897 }
898
899 }
900
901 static ctl_table unaligned_table[] = {
902 {
903 .ctl_name = CTL_UNNUMBERED,
904 .procname = "kernel_reports",
905 .data = &kernel_mode_unaligned_fixup_count,
906 .maxlen = sizeof(int),
907 .mode = 0644,
908 .proc_handler = &proc_dointvec
909 },
910 #if defined(CONFIG_SH64_USER_MISALIGNED_FIXUP)
911 {
912 .ctl_name = CTL_UNNUMBERED,
913 .procname = "user_reports",
914 .data = &user_mode_unaligned_fixup_count,
915 .maxlen = sizeof(int),
916 .mode = 0644,
917 .proc_handler = &proc_dointvec
918 },
919 {
920 .ctl_name = CTL_UNNUMBERED,
921 .procname = "user_enable",
922 .data = &user_mode_unaligned_fixup_enable,
923 .maxlen = sizeof(int),
924 .mode = 0644,
925 .proc_handler = &proc_dointvec},
926 #endif
927 {}
928 };
929
930 static ctl_table unaligned_root[] = {
931 {
932 .ctl_name = CTL_UNNUMBERED,
933 .procname = "unaligned_fixup",
934 .mode = 0555,
935 unaligned_table
936 },
937 {}
938 };
939
940 static ctl_table sh64_root[] = {
941 {
942 .ctl_name = CTL_UNNUMBERED,
943 .procname = "sh64",
944 .mode = 0555,
945 .child = unaligned_root
946 },
947 {}
948 };
949 static struct ctl_table_header *sysctl_header;
init_sysctl(void)950 static int __init init_sysctl(void)
951 {
952 sysctl_header = register_sysctl_table(sh64_root);
953 return 0;
954 }
955
956 __initcall(init_sysctl);
957
958
do_debug_interrupt(unsigned long code,struct pt_regs * regs)959 asmlinkage void do_debug_interrupt(unsigned long code, struct pt_regs *regs)
960 {
961 u64 peek_real_address_q(u64 addr);
962 u64 poke_real_address_q(u64 addr, u64 val);
963 unsigned long long DM_EXP_CAUSE_PHY = 0x0c100010;
964 unsigned long long exp_cause;
965 /* It's not worth ioremapping the debug module registers for the amount
966 of access we make to them - just go direct to their physical
967 addresses. */
968 exp_cause = peek_real_address_q(DM_EXP_CAUSE_PHY);
969 if (exp_cause & ~4) {
970 printk("DM.EXP_CAUSE had unexpected bits set (=%08lx)\n",
971 (unsigned long)(exp_cause & 0xffffffff));
972 }
973 show_state();
974 /* Clear all DEBUGINT causes */
975 poke_real_address_q(DM_EXP_CAUSE_PHY, 0x0);
976 }
977