Merge branch 'regset' (PTRACE_SETREGSET data leakage)
[linux-block.git] / 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         return 0;
148 }
149
150 int ptrace_getfpregs(struct task_struct *child, __u32 __user *data)
151 {
152         int i;
153
154         if (!access_ok(VERIFY_WRITE, data, 33 * 8))
155                 return -EIO;
156
157         if (tsk_used_math(child)) {
158                 union fpureg *fregs = get_fpu_regs(child);
159                 for (i = 0; i < 32; i++)
160                         __put_user(get_fpr64(&fregs[i], 0),
161                                    i + (__u64 __user *)data);
162         } else {
163                 for (i = 0; i < 32; i++)
164                         __put_user((__u64) -1, i + (__u64 __user *) data);
165         }
166
167         __put_user(child->thread.fpu.fcr31, data + 64);
168         __put_user(boot_cpu_data.fpu_id, data + 65);
169
170         return 0;
171 }
172
173 int ptrace_setfpregs(struct task_struct *child, __u32 __user *data)
174 {
175         union fpureg *fregs;
176         u64 fpr_val;
177         u32 value;
178         int i;
179
180         if (!access_ok(VERIFY_READ, data, 33 * 8))
181                 return -EIO;
182
183         init_fp_ctx(child);
184         fregs = get_fpu_regs(child);
185
186         for (i = 0; i < 32; i++) {
187                 __get_user(fpr_val, i + (__u64 __user *)data);
188                 set_fpr64(&fregs[i], 0, fpr_val);
189         }
190
191         __get_user(value, data + 64);
192         ptrace_setfcr31(child, value);
193
194         /* FIR may not be written.  */
195
196         return 0;
197 }
198
199 int ptrace_get_watch_regs(struct task_struct *child,
200                           struct pt_watch_regs __user *addr)
201 {
202         enum pt_watch_style style;
203         int i;
204
205         if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
206                 return -EIO;
207         if (!access_ok(VERIFY_WRITE, addr, sizeof(struct pt_watch_regs)))
208                 return -EIO;
209
210 #ifdef CONFIG_32BIT
211         style = pt_watch_style_mips32;
212 #define WATCH_STYLE mips32
213 #else
214         style = pt_watch_style_mips64;
215 #define WATCH_STYLE mips64
216 #endif
217
218         __put_user(style, &addr->style);
219         __put_user(boot_cpu_data.watch_reg_use_cnt,
220                    &addr->WATCH_STYLE.num_valid);
221         for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
222                 __put_user(child->thread.watch.mips3264.watchlo[i],
223                            &addr->WATCH_STYLE.watchlo[i]);
224                 __put_user(child->thread.watch.mips3264.watchhi[i] &
225                                 (MIPS_WATCHHI_MASK | MIPS_WATCHHI_IRW),
226                            &addr->WATCH_STYLE.watchhi[i]);
227                 __put_user(boot_cpu_data.watch_reg_masks[i],
228                            &addr->WATCH_STYLE.watch_masks[i]);
229         }
230         for (; i < 8; i++) {
231                 __put_user(0, &addr->WATCH_STYLE.watchlo[i]);
232                 __put_user(0, &addr->WATCH_STYLE.watchhi[i]);
233                 __put_user(0, &addr->WATCH_STYLE.watch_masks[i]);
234         }
235
236         return 0;
237 }
238
239 int ptrace_set_watch_regs(struct task_struct *child,
240                           struct pt_watch_regs __user *addr)
241 {
242         int i;
243         int watch_active = 0;
244         unsigned long lt[NUM_WATCH_REGS];
245         u16 ht[NUM_WATCH_REGS];
246
247         if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
248                 return -EIO;
249         if (!access_ok(VERIFY_READ, addr, sizeof(struct pt_watch_regs)))
250                 return -EIO;
251         /* Check the values. */
252         for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
253                 __get_user(lt[i], &addr->WATCH_STYLE.watchlo[i]);
254 #ifdef CONFIG_32BIT
255                 if (lt[i] & __UA_LIMIT)
256                         return -EINVAL;
257 #else
258                 if (test_tsk_thread_flag(child, TIF_32BIT_ADDR)) {
259                         if (lt[i] & 0xffffffff80000000UL)
260                                 return -EINVAL;
261                 } else {
262                         if (lt[i] & __UA_LIMIT)
263                                 return -EINVAL;
264                 }
265 #endif
266                 __get_user(ht[i], &addr->WATCH_STYLE.watchhi[i]);
267                 if (ht[i] & ~MIPS_WATCHHI_MASK)
268                         return -EINVAL;
269         }
270         /* Install them. */
271         for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
272                 if (lt[i] & MIPS_WATCHLO_IRW)
273                         watch_active = 1;
274                 child->thread.watch.mips3264.watchlo[i] = lt[i];
275                 /* Set the G bit. */
276                 child->thread.watch.mips3264.watchhi[i] = ht[i];
277         }
278
279         if (watch_active)
280                 set_tsk_thread_flag(child, TIF_LOAD_WATCH);
281         else
282                 clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
283
284         return 0;
285 }
286
287 /* regset get/set implementations */
288
289 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
290
291 static int gpr32_get(struct task_struct *target,
292                      const struct user_regset *regset,
293                      unsigned int pos, unsigned int count,
294                      void *kbuf, void __user *ubuf)
295 {
296         struct pt_regs *regs = task_pt_regs(target);
297         u32 uregs[ELF_NGREG] = {};
298
299         mips_dump_regs32(uregs, regs);
300         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
301                                    sizeof(uregs));
302 }
303
304 static int gpr32_set(struct task_struct *target,
305                      const struct user_regset *regset,
306                      unsigned int pos, unsigned int count,
307                      const void *kbuf, const void __user *ubuf)
308 {
309         struct pt_regs *regs = task_pt_regs(target);
310         u32 uregs[ELF_NGREG];
311         unsigned start, num_regs, i;
312         int err;
313
314         start = pos / sizeof(u32);
315         num_regs = count / sizeof(u32);
316
317         if (start + num_regs > ELF_NGREG)
318                 return -EIO;
319
320         err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
321                                  sizeof(uregs));
322         if (err)
323                 return err;
324
325         for (i = start; i < num_regs; i++) {
326                 /*
327                  * Cast all values to signed here so that if this is a 64-bit
328                  * kernel, the supplied 32-bit values will be sign extended.
329                  */
330                 switch (i) {
331                 case MIPS32_EF_R1 ... MIPS32_EF_R25:
332                         /* k0/k1 are ignored. */
333                 case MIPS32_EF_R28 ... MIPS32_EF_R31:
334                         regs->regs[i - MIPS32_EF_R0] = (s32)uregs[i];
335                         break;
336                 case MIPS32_EF_LO:
337                         regs->lo = (s32)uregs[i];
338                         break;
339                 case MIPS32_EF_HI:
340                         regs->hi = (s32)uregs[i];
341                         break;
342                 case MIPS32_EF_CP0_EPC:
343                         regs->cp0_epc = (s32)uregs[i];
344                         break;
345                 }
346         }
347
348         return 0;
349 }
350
351 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
352
353 #ifdef CONFIG_64BIT
354
355 static int gpr64_get(struct task_struct *target,
356                      const struct user_regset *regset,
357                      unsigned int pos, unsigned int count,
358                      void *kbuf, void __user *ubuf)
359 {
360         struct pt_regs *regs = task_pt_regs(target);
361         u64 uregs[ELF_NGREG] = {};
362
363         mips_dump_regs64(uregs, regs);
364         return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
365                                    sizeof(uregs));
366 }
367
368 static int gpr64_set(struct task_struct *target,
369                      const struct user_regset *regset,
370                      unsigned int pos, unsigned int count,
371                      const void *kbuf, const void __user *ubuf)
372 {
373         struct pt_regs *regs = task_pt_regs(target);
374         u64 uregs[ELF_NGREG];
375         unsigned start, num_regs, i;
376         int err;
377
378         start = pos / sizeof(u64);
379         num_regs = count / sizeof(u64);
380
381         if (start + num_regs > ELF_NGREG)
382                 return -EIO;
383
384         err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
385                                  sizeof(uregs));
386         if (err)
387                 return err;
388
389         for (i = start; i < num_regs; i++) {
390                 switch (i) {
391                 case MIPS64_EF_R1 ... MIPS64_EF_R25:
392                         /* k0/k1 are ignored. */
393                 case MIPS64_EF_R28 ... MIPS64_EF_R31:
394                         regs->regs[i - MIPS64_EF_R0] = uregs[i];
395                         break;
396                 case MIPS64_EF_LO:
397                         regs->lo = uregs[i];
398                         break;
399                 case MIPS64_EF_HI:
400                         regs->hi = uregs[i];
401                         break;
402                 case MIPS64_EF_CP0_EPC:
403                         regs->cp0_epc = uregs[i];
404                         break;
405                 }
406         }
407
408         return 0;
409 }
410
411 #endif /* CONFIG_64BIT */
412
413 static int fpr_get(struct task_struct *target,
414                    const struct user_regset *regset,
415                    unsigned int pos, unsigned int count,
416                    void *kbuf, void __user *ubuf)
417 {
418         unsigned i;
419         int err;
420         u64 fpr_val;
421
422         /* XXX fcr31  */
423
424         if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
425                 return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
426                                            &target->thread.fpu,
427                                            0, sizeof(elf_fpregset_t));
428
429         for (i = 0; i < NUM_FPU_REGS; i++) {
430                 fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
431                 err = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
432                                           &fpr_val, i * sizeof(elf_fpreg_t),
433                                           (i + 1) * sizeof(elf_fpreg_t));
434                 if (err)
435                         return err;
436         }
437
438         return 0;
439 }
440
441 static int fpr_set(struct task_struct *target,
442                    const struct user_regset *regset,
443                    unsigned int pos, unsigned int count,
444                    const void *kbuf, const void __user *ubuf)
445 {
446         unsigned i;
447         int err;
448         u64 fpr_val;
449
450         /* XXX fcr31  */
451
452         init_fp_ctx(target);
453
454         if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
455                 return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
456                                           &target->thread.fpu,
457                                           0, sizeof(elf_fpregset_t));
458
459         BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
460         for (i = 0; i < NUM_FPU_REGS && count >= sizeof(elf_fpreg_t); i++) {
461                 err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
462                                          &fpr_val, i * sizeof(elf_fpreg_t),
463                                          (i + 1) * sizeof(elf_fpreg_t));
464                 if (err)
465                         return err;
466                 set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
467         }
468
469         return 0;
470 }
471
472 enum mips_regset {
473         REGSET_GPR,
474         REGSET_FPR,
475 };
476
477 struct pt_regs_offset {
478         const char *name;
479         int offset;
480 };
481
482 #define REG_OFFSET_NAME(reg, r) {                                       \
483         .name = #reg,                                                   \
484         .offset = offsetof(struct pt_regs, r)                           \
485 }
486
487 #define REG_OFFSET_END {                                                \
488         .name = NULL,                                                   \
489         .offset = 0                                                     \
490 }
491
492 static const struct pt_regs_offset regoffset_table[] = {
493         REG_OFFSET_NAME(r0, regs[0]),
494         REG_OFFSET_NAME(r1, regs[1]),
495         REG_OFFSET_NAME(r2, regs[2]),
496         REG_OFFSET_NAME(r3, regs[3]),
497         REG_OFFSET_NAME(r4, regs[4]),
498         REG_OFFSET_NAME(r5, regs[5]),
499         REG_OFFSET_NAME(r6, regs[6]),
500         REG_OFFSET_NAME(r7, regs[7]),
501         REG_OFFSET_NAME(r8, regs[8]),
502         REG_OFFSET_NAME(r9, regs[9]),
503         REG_OFFSET_NAME(r10, regs[10]),
504         REG_OFFSET_NAME(r11, regs[11]),
505         REG_OFFSET_NAME(r12, regs[12]),
506         REG_OFFSET_NAME(r13, regs[13]),
507         REG_OFFSET_NAME(r14, regs[14]),
508         REG_OFFSET_NAME(r15, regs[15]),
509         REG_OFFSET_NAME(r16, regs[16]),
510         REG_OFFSET_NAME(r17, regs[17]),
511         REG_OFFSET_NAME(r18, regs[18]),
512         REG_OFFSET_NAME(r19, regs[19]),
513         REG_OFFSET_NAME(r20, regs[20]),
514         REG_OFFSET_NAME(r21, regs[21]),
515         REG_OFFSET_NAME(r22, regs[22]),
516         REG_OFFSET_NAME(r23, regs[23]),
517         REG_OFFSET_NAME(r24, regs[24]),
518         REG_OFFSET_NAME(r25, regs[25]),
519         REG_OFFSET_NAME(r26, regs[26]),
520         REG_OFFSET_NAME(r27, regs[27]),
521         REG_OFFSET_NAME(r28, regs[28]),
522         REG_OFFSET_NAME(r29, regs[29]),
523         REG_OFFSET_NAME(r30, regs[30]),
524         REG_OFFSET_NAME(r31, regs[31]),
525         REG_OFFSET_NAME(c0_status, cp0_status),
526         REG_OFFSET_NAME(hi, hi),
527         REG_OFFSET_NAME(lo, lo),
528 #ifdef CONFIG_CPU_HAS_SMARTMIPS
529         REG_OFFSET_NAME(acx, acx),
530 #endif
531         REG_OFFSET_NAME(c0_badvaddr, cp0_badvaddr),
532         REG_OFFSET_NAME(c0_cause, cp0_cause),
533         REG_OFFSET_NAME(c0_epc, cp0_epc),
534 #ifdef CONFIG_CPU_CAVIUM_OCTEON
535         REG_OFFSET_NAME(mpl0, mpl[0]),
536         REG_OFFSET_NAME(mpl1, mpl[1]),
537         REG_OFFSET_NAME(mpl2, mpl[2]),
538         REG_OFFSET_NAME(mtp0, mtp[0]),
539         REG_OFFSET_NAME(mtp1, mtp[1]),
540         REG_OFFSET_NAME(mtp2, mtp[2]),
541 #endif
542         REG_OFFSET_END,
543 };
544
545 /**
546  * regs_query_register_offset() - query register offset from its name
547  * @name:       the name of a register
548  *
549  * regs_query_register_offset() returns the offset of a register in struct
550  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
551  */
552 int regs_query_register_offset(const char *name)
553 {
554         const struct pt_regs_offset *roff;
555         for (roff = regoffset_table; roff->name != NULL; roff++)
556                 if (!strcmp(roff->name, name))
557                         return roff->offset;
558         return -EINVAL;
559 }
560
561 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
562
563 static const struct user_regset mips_regsets[] = {
564         [REGSET_GPR] = {
565                 .core_note_type = NT_PRSTATUS,
566                 .n              = ELF_NGREG,
567                 .size           = sizeof(unsigned int),
568                 .align          = sizeof(unsigned int),
569                 .get            = gpr32_get,
570                 .set            = gpr32_set,
571         },
572         [REGSET_FPR] = {
573                 .core_note_type = NT_PRFPREG,
574                 .n              = ELF_NFPREG,
575                 .size           = sizeof(elf_fpreg_t),
576                 .align          = sizeof(elf_fpreg_t),
577                 .get            = fpr_get,
578                 .set            = fpr_set,
579         },
580 };
581
582 static const struct user_regset_view user_mips_view = {
583         .name           = "mips",
584         .e_machine      = ELF_ARCH,
585         .ei_osabi       = ELF_OSABI,
586         .regsets        = mips_regsets,
587         .n              = ARRAY_SIZE(mips_regsets),
588 };
589
590 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
591
592 #ifdef CONFIG_64BIT
593
594 static const struct user_regset mips64_regsets[] = {
595         [REGSET_GPR] = {
596                 .core_note_type = NT_PRSTATUS,
597                 .n              = ELF_NGREG,
598                 .size           = sizeof(unsigned long),
599                 .align          = sizeof(unsigned long),
600                 .get            = gpr64_get,
601                 .set            = gpr64_set,
602         },
603         [REGSET_FPR] = {
604                 .core_note_type = NT_PRFPREG,
605                 .n              = ELF_NFPREG,
606                 .size           = sizeof(elf_fpreg_t),
607                 .align          = sizeof(elf_fpreg_t),
608                 .get            = fpr_get,
609                 .set            = fpr_set,
610         },
611 };
612
613 static const struct user_regset_view user_mips64_view = {
614         .name           = "mips64",
615         .e_machine      = ELF_ARCH,
616         .ei_osabi       = ELF_OSABI,
617         .regsets        = mips64_regsets,
618         .n              = ARRAY_SIZE(mips64_regsets),
619 };
620
621 #endif /* CONFIG_64BIT */
622
623 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
624 {
625 #ifdef CONFIG_32BIT
626         return &user_mips_view;
627 #else
628 #ifdef CONFIG_MIPS32_O32
629         if (test_tsk_thread_flag(task, TIF_32BIT_REGS))
630                 return &user_mips_view;
631 #endif
632         return &user_mips64_view;
633 #endif
634 }
635
636 long arch_ptrace(struct task_struct *child, long request,
637                  unsigned long addr, unsigned long data)
638 {
639         int ret;
640         void __user *addrp = (void __user *) addr;
641         void __user *datavp = (void __user *) data;
642         unsigned long __user *datalp = (void __user *) data;
643
644         switch (request) {
645         /* when I and D space are separate, these will need to be fixed. */
646         case PTRACE_PEEKTEXT: /* read word at location addr. */
647         case PTRACE_PEEKDATA:
648                 ret = generic_ptrace_peekdata(child, addr, data);
649                 break;
650
651         /* Read the word at location addr in the USER area. */
652         case PTRACE_PEEKUSR: {
653                 struct pt_regs *regs;
654                 union fpureg *fregs;
655                 unsigned long tmp = 0;
656
657                 regs = task_pt_regs(child);
658                 ret = 0;  /* Default return value. */
659
660                 switch (addr) {
661                 case 0 ... 31:
662                         tmp = regs->regs[addr];
663                         break;
664                 case FPR_BASE ... FPR_BASE + 31:
665                         if (!tsk_used_math(child)) {
666                                 /* FP not yet used */
667                                 tmp = -1;
668                                 break;
669                         }
670                         fregs = get_fpu_regs(child);
671
672 #ifdef CONFIG_32BIT
673                         if (test_thread_flag(TIF_32BIT_FPREGS)) {
674                                 /*
675                                  * The odd registers are actually the high
676                                  * order bits of the values stored in the even
677                                  * registers - unless we're using r2k_switch.S.
678                                  */
679                                 tmp = get_fpr32(&fregs[(addr & ~1) - FPR_BASE],
680                                                 addr & 1);
681                                 break;
682                         }
683 #endif
684                         tmp = get_fpr32(&fregs[addr - FPR_BASE], 0);
685                         break;
686                 case PC:
687                         tmp = regs->cp0_epc;
688                         break;
689                 case CAUSE:
690                         tmp = regs->cp0_cause;
691                         break;
692                 case BADVADDR:
693                         tmp = regs->cp0_badvaddr;
694                         break;
695                 case MMHI:
696                         tmp = regs->hi;
697                         break;
698                 case MMLO:
699                         tmp = regs->lo;
700                         break;
701 #ifdef CONFIG_CPU_HAS_SMARTMIPS
702                 case ACX:
703                         tmp = regs->acx;
704                         break;
705 #endif
706                 case FPC_CSR:
707                         tmp = child->thread.fpu.fcr31;
708                         break;
709                 case FPC_EIR:
710                         /* implementation / version register */
711                         tmp = boot_cpu_data.fpu_id;
712                         break;
713                 case DSP_BASE ... DSP_BASE + 5: {
714                         dspreg_t *dregs;
715
716                         if (!cpu_has_dsp) {
717                                 tmp = 0;
718                                 ret = -EIO;
719                                 goto out;
720                         }
721                         dregs = __get_dsp_regs(child);
722                         tmp = (unsigned long) (dregs[addr - DSP_BASE]);
723                         break;
724                 }
725                 case DSP_CONTROL:
726                         if (!cpu_has_dsp) {
727                                 tmp = 0;
728                                 ret = -EIO;
729                                 goto out;
730                         }
731                         tmp = child->thread.dsp.dspcontrol;
732                         break;
733                 default:
734                         tmp = 0;
735                         ret = -EIO;
736                         goto out;
737                 }
738                 ret = put_user(tmp, datalp);
739                 break;
740         }
741
742         /* when I and D space are separate, this will have to be fixed. */
743         case PTRACE_POKETEXT: /* write the word at location addr. */
744         case PTRACE_POKEDATA:
745                 ret = generic_ptrace_pokedata(child, addr, data);
746                 break;
747
748         case PTRACE_POKEUSR: {
749                 struct pt_regs *regs;
750                 ret = 0;
751                 regs = task_pt_regs(child);
752
753                 switch (addr) {
754                 case 0 ... 31:
755                         regs->regs[addr] = data;
756                         break;
757                 case FPR_BASE ... FPR_BASE + 31: {
758                         union fpureg *fregs = get_fpu_regs(child);
759
760                         init_fp_ctx(child);
761 #ifdef CONFIG_32BIT
762                         if (test_thread_flag(TIF_32BIT_FPREGS)) {
763                                 /*
764                                  * The odd registers are actually the high
765                                  * order bits of the values stored in the even
766                                  * registers - unless we're using r2k_switch.S.
767                                  */
768                                 set_fpr32(&fregs[(addr & ~1) - FPR_BASE],
769                                           addr & 1, data);
770                                 break;
771                         }
772 #endif
773                         set_fpr64(&fregs[addr - FPR_BASE], 0, data);
774                         break;
775                 }
776                 case PC:
777                         regs->cp0_epc = data;
778                         break;
779                 case MMHI:
780                         regs->hi = data;
781                         break;
782                 case MMLO:
783                         regs->lo = data;
784                         break;
785 #ifdef CONFIG_CPU_HAS_SMARTMIPS
786                 case ACX:
787                         regs->acx = data;
788                         break;
789 #endif
790                 case FPC_CSR:
791                         init_fp_ctx(child);
792                         ptrace_setfcr31(child, data);
793                         break;
794                 case DSP_BASE ... DSP_BASE + 5: {
795                         dspreg_t *dregs;
796
797                         if (!cpu_has_dsp) {
798                                 ret = -EIO;
799                                 break;
800                         }
801
802                         dregs = __get_dsp_regs(child);
803                         dregs[addr - DSP_BASE] = data;
804                         break;
805                 }
806                 case DSP_CONTROL:
807                         if (!cpu_has_dsp) {
808                                 ret = -EIO;
809                                 break;
810                         }
811                         child->thread.dsp.dspcontrol = data;
812                         break;
813                 default:
814                         /* The rest are not allowed. */
815                         ret = -EIO;
816                         break;
817                 }
818                 break;
819                 }
820
821         case PTRACE_GETREGS:
822                 ret = ptrace_getregs(child, datavp);
823                 break;
824
825         case PTRACE_SETREGS:
826                 ret = ptrace_setregs(child, datavp);
827                 break;
828
829         case PTRACE_GETFPREGS:
830                 ret = ptrace_getfpregs(child, datavp);
831                 break;
832
833         case PTRACE_SETFPREGS:
834                 ret = ptrace_setfpregs(child, datavp);
835                 break;
836
837         case PTRACE_GET_THREAD_AREA:
838                 ret = put_user(task_thread_info(child)->tp_value, datalp);
839                 break;
840
841         case PTRACE_GET_WATCH_REGS:
842                 ret = ptrace_get_watch_regs(child, addrp);
843                 break;
844
845         case PTRACE_SET_WATCH_REGS:
846                 ret = ptrace_set_watch_regs(child, addrp);
847                 break;
848
849         default:
850                 ret = ptrace_request(child, request, addr, data);
851                 break;
852         }
853  out:
854         return ret;
855 }
856
857 /*
858  * Notification of system call entry/exit
859  * - triggered by current->work.syscall_trace
860  */
861 asmlinkage long syscall_trace_enter(struct pt_regs *regs, long syscall)
862 {
863         user_exit();
864
865         current_thread_info()->syscall = syscall;
866
867         if (test_thread_flag(TIF_SYSCALL_TRACE) &&
868             tracehook_report_syscall_entry(regs))
869                 return -1;
870
871         if (secure_computing(NULL) == -1)
872                 return -1;
873
874         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
875                 trace_sys_enter(regs, regs->regs[2]);
876
877         audit_syscall_entry(syscall, regs->regs[4], regs->regs[5],
878                             regs->regs[6], regs->regs[7]);
879         return syscall;
880 }
881
882 /*
883  * Notification of system call entry/exit
884  * - triggered by current->work.syscall_trace
885  */
886 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
887 {
888         /*
889          * We may come here right after calling schedule_user()
890          * or do_notify_resume(), in which case we can be in RCU
891          * user mode.
892          */
893         user_exit();
894
895         audit_syscall_exit(regs);
896
897         if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
898                 trace_sys_exit(regs, regs->regs[2]);
899
900         if (test_thread_flag(TIF_SYSCALL_TRACE))
901                 tracehook_report_syscall_exit(regs, 0);
902
903         user_enter();
904 }