Merge tag 'mips_4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/mips
[linux] / arch / mips / kernel / ptrace.c
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1992 Ross Biro
7  * Copyright (C) Linus Torvalds
8  * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
9  * Copyright (C) 1996 David S. Miller
10  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
11  * Copyright (C) 1999 MIPS Technologies, Inc.
12  * Copyright (C) 2000 Ulf Carlsson
13  *
14  * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
15  * binaries.
16  */
17 #include <linux/compiler.h>
18 #include <linux/context_tracking.h>
19 #include <linux/elf.h>
20 #include <linux/kernel.h>
21 #include <linux/sched.h>
22 #include <linux/sched/task_stack.h>
23 #include <linux/mm.h>
24 #include <linux/errno.h>
25 #include <linux/ptrace.h>
26 #include <linux/regset.h>
27 #include <linux/smp.h>
28 #include <linux/security.h>
29 #include <linux/stddef.h>
30 #include <linux/tracehook.h>
31 #include <linux/audit.h>
32 #include <linux/seccomp.h>
33 #include <linux/ftrace.h>
34
35 #include <asm/byteorder.h>
36 #include <asm/cpu.h>
37 #include <asm/cpu-info.h>
38 #include <asm/dsp.h>
39 #include <asm/fpu.h>
40 #include <asm/mipsregs.h>
41 #include <asm/mipsmtregs.h>
42 #include <asm/pgtable.h>
43 #include <asm/page.h>
44 #include <asm/syscall.h>
45 #include <linux/uaccess.h>
46 #include <asm/bootinfo.h>
47 #include <asm/reg.h>
48
49 #define CREATE_TRACE_POINTS
50 #include <trace/events/syscalls.h>
51
52 static void init_fp_ctx(struct task_struct *target)
53 {
54         /* If FP has been used then the target already has context */
55         if (tsk_used_math(target))
56                 return;
57
58         /* Begin with data registers set to all 1s... */
59         memset(&target->thread.fpu.fpr, ~0, sizeof(target->thread.fpu.fpr));
60
61         /* FCSR has been preset by `mips_set_personality_nan'.  */
62
63         /*
64          * Record that the target has "used" math, such that the context
65          * just initialised, and any modifications made by the caller,
66          * aren't discarded.
67          */
68         set_stopped_child_used_math(target);
69 }
70
71 /*
72  * Called by kernel/ptrace.c when detaching..
73  *
74  * Make sure single step bits etc are not set.
75  */
76 void ptrace_disable(struct task_struct *child)
77 {
78         /* Don't load the watchpoint registers for the ex-child. */
79         clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
80 }
81
82 /*
83  * Poke at FCSR according to its mask.  Set the Cause bits even
84  * if a corresponding Enable bit is set.  This will be noticed at
85  * the time the thread is switched to and SIGFPE thrown accordingly.
86  */
87 static void ptrace_setfcr31(struct task_struct *child, u32 value)
88 {
89         u32 fcr31;
90         u32 mask;
91
92         fcr31 = child->thread.fpu.fcr31;
93         mask = boot_cpu_data.fpu_msk31;
94         child->thread.fpu.fcr31 = (value & ~mask) | (fcr31 & mask);
95 }
96
97 /*
98  * Read a general register set.  We always use the 64-bit format, even
99  * for 32-bit kernels and for 32-bit processes on a 64-bit kernel.
100  * Registers are sign extended to fill the available space.
101  */
102 int ptrace_getregs(struct task_struct *child, struct user_pt_regs __user *data)
103 {
104         struct pt_regs *regs;
105         int i;
106
107         if (!access_ok(VERIFY_WRITE, data, 38 * 8))
108                 return -EIO;
109
110         regs = task_pt_regs(child);
111
112         for (i = 0; i < 32; i++)
113                 __put_user((long)regs->regs[i], (__s64 __user *)&data->regs[i]);
114         __put_user((long)regs->lo, (__s64 __user *)&data->lo);
115         __put_user((long)regs->hi, (__s64 __user *)&data->hi);
116         __put_user((long)regs->cp0_epc, (__s64 __user *)&data->cp0_epc);
117         __put_user((long)regs->cp0_badvaddr, (__s64 __user *)&data->cp0_badvaddr);
118         __put_user((long)regs->cp0_status, (__s64 __user *)&data->cp0_status);
119         __put_user((long)regs->cp0_cause, (__s64 __user *)&data->cp0_cause);
120
121         return 0;
122 }
123
124 /*
125  * Write a general register set.  As for PTRACE_GETREGS, we always use
126  * the 64-bit format.  On a 32-bit kernel only the lower order half
127  * (according to endianness) will be used.
128  */
129 int ptrace_setregs(struct task_struct *child, struct user_pt_regs __user *data)
130 {
131         struct pt_regs *regs;
132         int i;
133
134         if (!access_ok(VERIFY_READ, data, 38 * 8))
135                 return -EIO;
136
137         regs = task_pt_regs(child);
138
139         for (i = 0; i < 32; i++)
140                 __get_user(regs->regs[i], (__s64 __user *)&data->regs[i]);
141         __get_user(regs->lo, (__s64 __user *)&data->lo);
142         __get_user(regs->hi, (__s64 __user *)&data->hi);
143         __get_user(regs->cp0_epc, (__s64 __user *)&data->cp0_epc);
144
145         /* badvaddr, status, and cause may not be written.  */
146
147         /* System call number may have been changed */
148         mips_syscall_update_nr(child, regs);
149
150         return 0;
151 }
152
153 int ptrace_getfpregs(struct task_struct *child, __u32 __user *data)
154 {
155         int i;
156
157         if (!access_ok(VERIFY_WRITE, data, 33 * 8))
158                 return -EIO;
159
160         if (tsk_used_math(child)) {
161                 union fpureg *fregs = get_fpu_regs(child);
162                 for (i = 0; i < 32; i++)
163                         __put_user(get_fpr64(&fregs[i], 0),
164                                    i + (__u64 __user *)data);
165         } else {
166                 for (i = 0; i < 32; i++)
167                         __put_user((__u64) -1, i + (__u64 __user *) data);
168         }
169
170         __put_user(child->thread.fpu.fcr31, data + 64);
171         __put_user(boot_cpu_data.fpu_id, data + 65);
172
173         return 0;
174 }
175
176 int ptrace_setfpregs(struct task_struct *child, __u32 __user *data)
177 {
178         union fpureg *fregs;
179         u64 fpr_val;
180         u32 value;
181         int i;
182
183         if (!access_ok(VERIFY_READ, data, 33 * 8))
184                 return -EIO;
185
186         init_fp_ctx(child);
187         fregs = get_fpu_regs(child);
188
189         for (i = 0; i < 32; i++) {
190                 __get_user(fpr_val, i + (__u64 __user *)data);
191                 set_fpr64(&fregs[i], 0, fpr_val);
192         }
193
194         __get_user(value, data + 64);
195         ptrace_setfcr31(child, value);
196
197         /* FIR may not be written.  */
198
199         return 0;
200 }
201
202 int ptrace_get_watch_regs(struct task_struct *child,
203                           struct pt_watch_regs __user *addr)
204 {
205         enum pt_watch_style style;
206         int i;
207
208         if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
209                 return -EIO;
210         if (!access_ok(VERIFY_WRITE, addr, sizeof(struct pt_watch_regs)))
211                 return -EIO;
212
213 #ifdef CONFIG_32BIT
214         style = pt_watch_style_mips32;
215 #define WATCH_STYLE mips32
216 #else
217         style = pt_watch_style_mips64;
218 #define WATCH_STYLE mips64
219 #endif
220
221         __put_user(style, &addr->style);
222         __put_user(boot_cpu_data.watch_reg_use_cnt,
223                    &addr->WATCH_STYLE.num_valid);
224         for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
225                 __put_user(child->thread.watch.mips3264.watchlo[i],
226                            &addr->WATCH_STYLE.watchlo[i]);
227                 __put_user(child->thread.watch.mips3264.watchhi[i] &
228                                 (MIPS_WATCHHI_MASK | MIPS_WATCHHI_IRW),
229                            &addr->WATCH_STYLE.watchhi[i]);
230                 __put_user(boot_cpu_data.watch_reg_masks[i],
231                            &addr->WATCH_STYLE.watch_masks[i]);
232         }
233         for (; i < 8; i++) {
234                 __put_user(0, &addr->WATCH_STYLE.watchlo[i]);
235                 __put_user(0, &addr->WATCH_STYLE.watchhi[i]);
236                 __put_user(0, &addr->WATCH_STYLE.watch_masks[i]);
237         }
238
239         return 0;
240 }
241
242 int ptrace_set_watch_regs(struct task_struct *child,
243                           struct pt_watch_regs __user *addr)
244 {
245         int i;
246         int watch_active = 0;
247         unsigned long lt[NUM_WATCH_REGS];
248         u16 ht[NUM_WATCH_REGS];
249
250         if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
251                 return -EIO;
252         if (!access_ok(VERIFY_READ, addr, sizeof(struct pt_watch_regs)))
253                 return -EIO;
254         /* Check the values. */
255         for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
256                 __get_user(lt[i], &addr->WATCH_STYLE.watchlo[i]);
257 #ifdef CONFIG_32BIT
258                 if (lt[i] & __UA_LIMIT)
259                         return -EINVAL;
260 #else
261                 if (test_tsk_thread_flag(child, TIF_32BIT_ADDR)) {
262                         if (lt[i] & 0xffffffff80000000UL)
263                                 return -EINVAL;
264                 } else {
265                         if (lt[i] & __UA_LIMIT)
266                                 return -EINVAL;
267                 }
268 #endif
269                 __get_user(ht[i], &addr->WATCH_STYLE.watchhi[i]);
270                 if (ht[i] & ~MIPS_WATCHHI_MASK)
271                         return -EINVAL;
272         }
273         /* Install them. */
274         for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
275                 if (lt[i] & MIPS_WATCHLO_IRW)
276                         watch_active = 1;
277                 child->thread.watch.mips3264.watchlo[i] = lt[i];
278                 /* Set the G bit. */
279                 child->thread.watch.mips3264.watchhi[i] = ht[i];
280         }
281
282         if (watch_active)
283                 set_tsk_thread_flag(child, TIF_LOAD_WATCH);
284         else
285                 clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
286
287         return 0;
288 }
289
290 /* regset get/set implementations */
291
292 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
293
294 static int gpr32_get(struct task_struct *target,
295                      const struct user_regset *regset,
296                      unsigned int pos, unsigned int count,
297                      void *kbuf, void __user *ubuf)
298 {
299         struct pt_regs *regs = task_pt_regs(target);
300         u32 uregs[ELF_NGREG] = {};
301
302         mips_dump_regs32(uregs, regs);
303         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
304                                    sizeof(uregs));
305 }
306
307 static int gpr32_set(struct task_struct *target,
308                      const struct user_regset *regset,
309                      unsigned int pos, unsigned int count,
310                      const void *kbuf, const void __user *ubuf)
311 {
312         struct pt_regs *regs = task_pt_regs(target);
313         u32 uregs[ELF_NGREG];
314         unsigned start, num_regs, i;
315         int err;
316
317         start = pos / sizeof(u32);
318         num_regs = count / sizeof(u32);
319
320         if (start + num_regs > ELF_NGREG)
321                 return -EIO;
322
323         err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
324                                  sizeof(uregs));
325         if (err)
326                 return err;
327
328         for (i = start; i < num_regs; i++) {
329                 /*
330                  * Cast all values to signed here so that if this is a 64-bit
331                  * kernel, the supplied 32-bit values will be sign extended.
332                  */
333                 switch (i) {
334                 case MIPS32_EF_R1 ... MIPS32_EF_R25:
335                         /* k0/k1 are ignored. */
336                 case MIPS32_EF_R28 ... MIPS32_EF_R31:
337                         regs->regs[i - MIPS32_EF_R0] = (s32)uregs[i];
338                         break;
339                 case MIPS32_EF_LO:
340                         regs->lo = (s32)uregs[i];
341                         break;
342                 case MIPS32_EF_HI:
343                         regs->hi = (s32)uregs[i];
344                         break;
345                 case MIPS32_EF_CP0_EPC:
346                         regs->cp0_epc = (s32)uregs[i];
347                         break;
348                 }
349         }
350
351         /* System call number may have been changed */
352         mips_syscall_update_nr(target, regs);
353
354         return 0;
355 }
356
357 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
358
359 #ifdef CONFIG_64BIT
360
361 static int gpr64_get(struct task_struct *target,
362                      const struct user_regset *regset,
363                      unsigned int pos, unsigned int count,
364                      void *kbuf, void __user *ubuf)
365 {
366         struct pt_regs *regs = task_pt_regs(target);
367         u64 uregs[ELF_NGREG] = {};
368
369         mips_dump_regs64(uregs, regs);
370         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
371                                    sizeof(uregs));
372 }
373
374 static int gpr64_set(struct task_struct *target,
375                      const struct user_regset *regset,
376                      unsigned int pos, unsigned int count,
377                      const void *kbuf, const void __user *ubuf)
378 {
379         struct pt_regs *regs = task_pt_regs(target);
380         u64 uregs[ELF_NGREG];
381         unsigned start, num_regs, i;
382         int err;
383
384         start = pos / sizeof(u64);
385         num_regs = count / sizeof(u64);
386
387         if (start + num_regs > ELF_NGREG)
388                 return -EIO;
389
390         err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
391                                  sizeof(uregs));
392         if (err)
393                 return err;
394
395         for (i = start; i < num_regs; i++) {
396                 switch (i) {
397                 case MIPS64_EF_R1 ... MIPS64_EF_R25:
398                         /* k0/k1 are ignored. */
399                 case MIPS64_EF_R28 ... MIPS64_EF_R31:
400                         regs->regs[i - MIPS64_EF_R0] = uregs[i];
401                         break;
402                 case MIPS64_EF_LO:
403                         regs->lo = uregs[i];
404                         break;
405                 case MIPS64_EF_HI:
406                         regs->hi = uregs[i];
407                         break;
408                 case MIPS64_EF_CP0_EPC:
409                         regs->cp0_epc = uregs[i];
410                         break;
411                 }
412         }
413
414         /* System call number may have been changed */
415         mips_syscall_update_nr(target, regs);
416
417         return 0;
418 }
419
420 #endif /* CONFIG_64BIT */
421
422 static int fpr_get(struct task_struct *target,
423                    const struct user_regset *regset,
424                    unsigned int pos, unsigned int count,
425                    void *kbuf, void __user *ubuf)
426 {
427         unsigned i;
428         int err;
429         u64 fpr_val;
430
431         /* XXX fcr31  */
432
433         if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
434                 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
435                                            &target->thread.fpu,
436                                            0, sizeof(elf_fpregset_t));
437
438         for (i = 0; i < NUM_FPU_REGS; i++) {
439                 fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
440                 err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
441                                           &fpr_val, i * sizeof(elf_fpreg_t),
442                                           (i + 1) * sizeof(elf_fpreg_t));
443                 if (err)
444                         return err;
445         }
446
447         return 0;
448 }
449
450 static int fpr_set(struct task_struct *target,
451                    const struct user_regset *regset,
452                    unsigned int pos, unsigned int count,
453                    const void *kbuf, const void __user *ubuf)
454 {
455         unsigned i;
456         int err;
457         u64 fpr_val;
458
459         /* XXX fcr31  */
460
461         init_fp_ctx(target);
462
463         if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
464                 return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
465                                           &target->thread.fpu,
466                                           0, sizeof(elf_fpregset_t));
467
468         BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
469         for (i = 0; i < NUM_FPU_REGS && count >= sizeof(elf_fpreg_t); i++) {
470                 err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
471                                          &fpr_val, i * sizeof(elf_fpreg_t),
472                                          (i + 1) * sizeof(elf_fpreg_t));
473                 if (err)
474                         return err;
475                 set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
476         }
477
478         return 0;
479 }
480
481 enum mips_regset {
482         REGSET_GPR,
483         REGSET_FPR,
484 };
485
486 struct pt_regs_offset {
487         const char *name;
488         int offset;
489 };
490
491 #define REG_OFFSET_NAME(reg, r) {                                       \
492         .name = #reg,                                                   \
493         .offset = offsetof(struct pt_regs, r)                           \
494 }
495
496 #define REG_OFFSET_END {                                                \
497         .name = NULL,                                                   \
498         .offset = 0                                                     \
499 }
500
501 static const struct pt_regs_offset regoffset_table[] = {
502         REG_OFFSET_NAME(r0, regs[0]),
503         REG_OFFSET_NAME(r1, regs[1]),
504         REG_OFFSET_NAME(r2, regs[2]),
505         REG_OFFSET_NAME(r3, regs[3]),
506         REG_OFFSET_NAME(r4, regs[4]),
507         REG_OFFSET_NAME(r5, regs[5]),
508         REG_OFFSET_NAME(r6, regs[6]),
509         REG_OFFSET_NAME(r7, regs[7]),
510         REG_OFFSET_NAME(r8, regs[8]),
511         REG_OFFSET_NAME(r9, regs[9]),
512         REG_OFFSET_NAME(r10, regs[10]),
513         REG_OFFSET_NAME(r11, regs[11]),
514         REG_OFFSET_NAME(r12, regs[12]),
515         REG_OFFSET_NAME(r13, regs[13]),
516         REG_OFFSET_NAME(r14, regs[14]),
517         REG_OFFSET_NAME(r15, regs[15]),
518         REG_OFFSET_NAME(r16, regs[16]),
519         REG_OFFSET_NAME(r17, regs[17]),
520         REG_OFFSET_NAME(r18, regs[18]),
521         REG_OFFSET_NAME(r19, regs[19]),
522         REG_OFFSET_NAME(r20, regs[20]),
523         REG_OFFSET_NAME(r21, regs[21]),
524         REG_OFFSET_NAME(r22, regs[22]),
525         REG_OFFSET_NAME(r23, regs[23]),
526         REG_OFFSET_NAME(r24, regs[24]),
527         REG_OFFSET_NAME(r25, regs[25]),
528         REG_OFFSET_NAME(r26, regs[26]),
529         REG_OFFSET_NAME(r27, regs[27]),
530         REG_OFFSET_NAME(r28, regs[28]),
531         REG_OFFSET_NAME(r29, regs[29]),
532         REG_OFFSET_NAME(r30, regs[30]),
533         REG_OFFSET_NAME(r31, regs[31]),
534         REG_OFFSET_NAME(c0_status, cp0_status),
535         REG_OFFSET_NAME(hi, hi),
536         REG_OFFSET_NAME(lo, lo),
537 #ifdef CONFIG_CPU_HAS_SMARTMIPS
538         REG_OFFSET_NAME(acx, acx),
539 #endif
540         REG_OFFSET_NAME(c0_badvaddr, cp0_badvaddr),
541         REG_OFFSET_NAME(c0_cause, cp0_cause),
542         REG_OFFSET_NAME(c0_epc, cp0_epc),
543 #ifdef CONFIG_CPU_CAVIUM_OCTEON
544         REG_OFFSET_NAME(mpl0, mpl[0]),
545         REG_OFFSET_NAME(mpl1, mpl[1]),
546         REG_OFFSET_NAME(mpl2, mpl[2]),
547         REG_OFFSET_NAME(mtp0, mtp[0]),
548         REG_OFFSET_NAME(mtp1, mtp[1]),
549         REG_OFFSET_NAME(mtp2, mtp[2]),
550 #endif
551         REG_OFFSET_END,
552 };
553
554 /**
555  * regs_query_register_offset() - query register offset from its name
556  * @name:       the name of a register
557  *
558  * regs_query_register_offset() returns the offset of a register in struct
559  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
560  */
561 int regs_query_register_offset(const char *name)
562 {
563         const struct pt_regs_offset *roff;
564         for (roff = regoffset_table; roff->name != NULL; roff++)
565                 if (!strcmp(roff->name, name))
566                         return roff->offset;
567         return -EINVAL;
568 }
569
570 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
571
572 static const struct user_regset mips_regsets[] = {
573         [REGSET_GPR] = {
574                 .core_note_type = NT_PRSTATUS,
575                 .n              = ELF_NGREG,
576                 .size           = sizeof(unsigned int),
577                 .align          = sizeof(unsigned int),
578                 .get            = gpr32_get,
579                 .set            = gpr32_set,
580         },
581         [REGSET_FPR] = {
582                 .core_note_type = NT_PRFPREG,
583                 .n              = ELF_NFPREG,
584                 .size           = sizeof(elf_fpreg_t),
585                 .align          = sizeof(elf_fpreg_t),
586                 .get            = fpr_get,
587                 .set            = fpr_set,
588         },
589 };
590
591 static const struct user_regset_view user_mips_view = {
592         .name           = "mips",
593         .e_machine      = ELF_ARCH,
594         .ei_osabi       = ELF_OSABI,
595         .regsets        = mips_regsets,
596         .n              = ARRAY_SIZE(mips_regsets),
597 };
598
599 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
600
601 #ifdef CONFIG_64BIT
602
603 static const struct user_regset mips64_regsets[] = {
604         [REGSET_GPR] = {
605                 .core_note_type = NT_PRSTATUS,
606                 .n              = ELF_NGREG,
607                 .size           = sizeof(unsigned long),
608                 .align          = sizeof(unsigned long),
609                 .get            = gpr64_get,
610                 .set            = gpr64_set,
611         },
612         [REGSET_FPR] = {
613                 .core_note_type = NT_PRFPREG,
614                 .n              = ELF_NFPREG,
615                 .size           = sizeof(elf_fpreg_t),
616                 .align          = sizeof(elf_fpreg_t),
617                 .get            = fpr_get,
618                 .set            = fpr_set,
619         },
620 };
621
622 static const struct user_regset_view user_mips64_view = {
623         .name           = "mips64",
624         .e_machine      = ELF_ARCH,
625         .ei_osabi       = ELF_OSABI,
626         .regsets        = mips64_regsets,
627         .n              = ARRAY_SIZE(mips64_regsets),
628 };
629
630 #ifdef CONFIG_MIPS32_N32
631
632 static const struct user_regset_view user_mipsn32_view = {
633         .name           = "mipsn32",
634         .e_flags        = EF_MIPS_ABI2,
635         .e_machine      = ELF_ARCH,
636         .ei_osabi       = ELF_OSABI,
637         .regsets        = mips64_regsets,
638         .n              = ARRAY_SIZE(mips64_regsets),
639 };
640
641 #endif /* CONFIG_MIPS32_N32 */
642
643 #endif /* CONFIG_64BIT */
644
645 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
646 {
647 #ifdef CONFIG_32BIT
648         return &user_mips_view;
649 #else
650 #ifdef CONFIG_MIPS32_O32
651         if (test_tsk_thread_flag(task, TIF_32BIT_REGS))
652                 return &user_mips_view;
653 #endif
654 #ifdef CONFIG_MIPS32_N32
655         if (test_tsk_thread_flag(task, TIF_32BIT_ADDR))
656                 return &user_mipsn32_view;
657 #endif
658         return &user_mips64_view;
659 #endif
660 }
661
662 long arch_ptrace(struct task_struct *child, long request,
663                  unsigned long addr, unsigned long data)
664 {
665         int ret;
666         void __user *addrp = (void __user *) addr;
667         void __user *datavp = (void __user *) data;
668         unsigned long __user *datalp = (void __user *) data;
669
670         switch (request) {
671         /* when I and D space are separate, these will need to be fixed. */
672         case PTRACE_PEEKTEXT: /* read word at location addr. */
673         case PTRACE_PEEKDATA:
674                 ret = generic_ptrace_peekdata(child, addr, data);
675                 break;
676
677         /* Read the word at location addr in the USER area. */
678         case PTRACE_PEEKUSR: {
679                 struct pt_regs *regs;
680                 union fpureg *fregs;
681                 unsigned long tmp = 0;
682
683                 regs = task_pt_regs(child);
684                 ret = 0;  /* Default return value. */
685
686                 switch (addr) {
687                 case 0 ... 31:
688                         tmp = regs->regs[addr];
689                         break;
690                 case FPR_BASE ... FPR_BASE + 31:
691                         if (!tsk_used_math(child)) {
692                                 /* FP not yet used */
693                                 tmp = -1;
694                                 break;
695                         }
696                         fregs = get_fpu_regs(child);
697
698 #ifdef CONFIG_32BIT
699                         if (test_thread_flag(TIF_32BIT_FPREGS)) {
700                                 /*
701                                  * The odd registers are actually the high
702                                  * order bits of the values stored in the even
703                                  * registers - unless we're using r2k_switch.S.
704                                  */
705                                 tmp = get_fpr32(&fregs[(addr & ~1) - FPR_BASE],
706                                                 addr & 1);
707                                 break;
708                         }
709 #endif
710                         tmp = get_fpr32(&fregs[addr - FPR_BASE], 0);
711                         break;
712                 case PC:
713                         tmp = regs->cp0_epc;
714                         break;
715                 case CAUSE:
716                         tmp = regs->cp0_cause;
717                         break;
718                 case BADVADDR:
719                         tmp = regs->cp0_badvaddr;
720                         break;
721                 case MMHI:
722                         tmp = regs->hi;
723                         break;
724                 case MMLO:
725                         tmp = regs->lo;
726                         break;
727 #ifdef CONFIG_CPU_HAS_SMARTMIPS
728                 case ACX:
729                         tmp = regs->acx;
730                         break;
731 #endif
732                 case FPC_CSR:
733                         tmp = child->thread.fpu.fcr31;
734                         break;
735                 case FPC_EIR:
736                         /* implementation / version register */
737                         tmp = boot_cpu_data.fpu_id;
738                         break;
739                 case DSP_BASE ... DSP_BASE + 5: {
740                         dspreg_t *dregs;
741
742                         if (!cpu_has_dsp) {
743                                 tmp = 0;
744                                 ret = -EIO;
745                                 goto out;
746                         }
747                         dregs = __get_dsp_regs(child);
748                         tmp = (unsigned long) (dregs[addr - DSP_BASE]);
749                         break;
750                 }
751                 case DSP_CONTROL:
752                         if (!cpu_has_dsp) {
753                                 tmp = 0;
754                                 ret = -EIO;
755                                 goto out;
756                         }
757                         tmp = child->thread.dsp.dspcontrol;
758                         break;
759                 default:
760                         tmp = 0;
761                         ret = -EIO;
762                         goto out;
763                 }
764                 ret = put_user(tmp, datalp);
765                 break;
766         }
767
768         /* when I and D space are separate, this will have to be fixed. */
769         case PTRACE_POKETEXT: /* write the word at location addr. */
770         case PTRACE_POKEDATA:
771                 ret = generic_ptrace_pokedata(child, addr, data);
772                 break;
773
774         case PTRACE_POKEUSR: {
775                 struct pt_regs *regs;
776                 ret = 0;
777                 regs = task_pt_regs(child);
778
779                 switch (addr) {
780                 case 0 ... 31:
781                         regs->regs[addr] = data;
782                         /* System call number may have been changed */
783                         if (addr == 2)
784                                 mips_syscall_update_nr(child, regs);
785                         else if (addr == 4 &&
786                                  mips_syscall_is_indirect(child, regs))
787                                 mips_syscall_update_nr(child, regs);
788                         break;
789                 case FPR_BASE ... FPR_BASE + 31: {
790                         union fpureg *fregs = get_fpu_regs(child);
791
792                         init_fp_ctx(child);
793 #ifdef CONFIG_32BIT
794                         if (test_thread_flag(TIF_32BIT_FPREGS)) {
795                                 /*
796                                  * The odd registers are actually the high
797                                  * order bits of the values stored in the even
798                                  * registers - unless we're using r2k_switch.S.
799                                  */
800                                 set_fpr32(&fregs[(addr & ~1) - FPR_BASE],
801                                           addr & 1, data);
802                                 break;
803                         }
804 #endif
805                         set_fpr64(&fregs[addr - FPR_BASE], 0, data);
806                         break;
807                 }
808                 case PC:
809                         regs->cp0_epc = data;
810                         break;
811                 case MMHI:
812                         regs->hi = data;
813                         break;
814                 case MMLO:
815                         regs->lo = data;
816                         break;
817 #ifdef CONFIG_CPU_HAS_SMARTMIPS
818                 case ACX:
819                         regs->acx = data;
820                         break;
821 #endif
822                 case FPC_CSR:
823                         init_fp_ctx(child);
824                         ptrace_setfcr31(child, data);
825                         break;
826                 case DSP_BASE ... DSP_BASE + 5: {
827                         dspreg_t *dregs;
828
829                         if (!cpu_has_dsp) {
830                                 ret = -EIO;
831                                 break;
832                         }
833
834                         dregs = __get_dsp_regs(child);
835                         dregs[addr - DSP_BASE] = data;
836                         break;
837                 }
838                 case DSP_CONTROL:
839                         if (!cpu_has_dsp) {
840                                 ret = -EIO;
841                                 break;
842                         }
843                         child->thread.dsp.dspcontrol = data;
844                         break;
845                 default:
846                         /* The rest are not allowed. */
847                         ret = -EIO;
848                         break;
849                 }
850                 break;
851                 }
852
853         case PTRACE_GETREGS:
854                 ret = ptrace_getregs(child, datavp);
855                 break;
856
857         case PTRACE_SETREGS:
858                 ret = ptrace_setregs(child, datavp);
859                 break;
860
861         case PTRACE_GETFPREGS:
862                 ret = ptrace_getfpregs(child, datavp);
863                 break;
864
865         case PTRACE_SETFPREGS:
866                 ret = ptrace_setfpregs(child, datavp);
867                 break;
868
869         case PTRACE_GET_THREAD_AREA:
870                 ret = put_user(task_thread_info(child)->tp_value, datalp);
871                 break;
872
873         case PTRACE_GET_WATCH_REGS:
874                 ret = ptrace_get_watch_regs(child, addrp);
875                 break;
876
877         case PTRACE_SET_WATCH_REGS:
878                 ret = ptrace_set_watch_regs(child, addrp);
879                 break;
880
881         default:
882                 ret = ptrace_request(child, request, addr, data);
883                 break;
884         }
885  out:
886         return ret;
887 }
888
889 /*
890  * Notification of system call entry/exit
891  * - triggered by current->work.syscall_trace
892  */
893 asmlinkage long syscall_trace_enter(struct pt_regs *regs, long syscall)
894 {
895         user_exit();
896
897         current_thread_info()->syscall = syscall;
898
899         if (test_thread_flag(TIF_SYSCALL_TRACE)) {
900                 if (tracehook_report_syscall_entry(regs))
901                         return -1;
902                 syscall = current_thread_info()->syscall;
903         }
904
905 #ifdef CONFIG_SECCOMP
906         if (unlikely(test_thread_flag(TIF_SECCOMP))) {
907                 int ret, i;
908                 struct seccomp_data sd;
909                 unsigned long args[6];
910
911                 sd.nr = syscall;
912                 sd.arch = syscall_get_arch();
913                 syscall_get_arguments(current, regs, 0, 6, args);
914                 for (i = 0; i < 6; i++)
915                         sd.args[i] = args[i];
916                 sd.instruction_pointer = KSTK_EIP(current);
917
918                 ret = __secure_computing(&sd);
919                 if (ret == -1)
920                         return ret;
921                 syscall = current_thread_info()->syscall;
922         }
923 #endif
924
925         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
926                 trace_sys_enter(regs, regs->regs[2]);
927
928         audit_syscall_entry(syscall, regs->regs[4], regs->regs[5],
929                             regs->regs[6], regs->regs[7]);
930
931         /*
932          * Negative syscall numbers are mistaken for rejected syscalls, but
933          * won't have had the return value set appropriately, so we do so now.
934          */
935         if (syscall < 0)
936                 syscall_set_return_value(current, regs, -ENOSYS, 0);
937         return syscall;
938 }
939
940 /*
941  * Notification of system call entry/exit
942  * - triggered by current->work.syscall_trace
943  */
944 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
945 {
946         /*
947          * We may come here right after calling schedule_user()
948          * or do_notify_resume(), in which case we can be in RCU
949          * user mode.
950          */
951         user_exit();
952
953         audit_syscall_exit(regs);
954
955         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
956                 trace_sys_exit(regs, regs_return_value(regs));
957
958         if (test_thread_flag(TIF_SYSCALL_TRACE))
959                 tracehook_report_syscall_exit(regs, 0);
960
961         user_enter();
962 }