xref: /openbmc/linux/arch/mips/kernel/ptrace.c (revision abb84c46)
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/audit.h>
31 #include <linux/seccomp.h>
32 #include <linux/ftrace.h>
33 
34 #include <asm/branch.h>
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/page.h>
43 #include <asm/processor.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 unsigned long exception_ip(struct pt_regs *regs)
53 {
54 	return exception_epc(regs);
55 }
56 EXPORT_SYMBOL(exception_ip);
57 
58 /*
59  * Called by kernel/ptrace.c when detaching..
60  *
61  * Make sure single step bits etc are not set.
62  */
63 void ptrace_disable(struct task_struct *child)
64 {
65 	/* Don't load the watchpoint registers for the ex-child. */
66 	clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
67 }
68 
69 /*
70  * Read a general register set.	 We always use the 64-bit format, even
71  * for 32-bit kernels and for 32-bit processes on a 64-bit kernel.
72  * Registers are sign extended to fill the available space.
73  */
74 int ptrace_getregs(struct task_struct *child, struct user_pt_regs __user *data)
75 {
76 	struct pt_regs *regs;
77 	int i;
78 
79 	if (!access_ok(data, 38 * 8))
80 		return -EIO;
81 
82 	regs = task_pt_regs(child);
83 
84 	for (i = 0; i < 32; i++)
85 		__put_user((long)regs->regs[i], (__s64 __user *)&data->regs[i]);
86 	__put_user((long)regs->lo, (__s64 __user *)&data->lo);
87 	__put_user((long)regs->hi, (__s64 __user *)&data->hi);
88 	__put_user((long)regs->cp0_epc, (__s64 __user *)&data->cp0_epc);
89 	__put_user((long)regs->cp0_badvaddr, (__s64 __user *)&data->cp0_badvaddr);
90 	__put_user((long)regs->cp0_status, (__s64 __user *)&data->cp0_status);
91 	__put_user((long)regs->cp0_cause, (__s64 __user *)&data->cp0_cause);
92 
93 	return 0;
94 }
95 
96 /*
97  * Write a general register set.  As for PTRACE_GETREGS, we always use
98  * the 64-bit format.  On a 32-bit kernel only the lower order half
99  * (according to endianness) will be used.
100  */
101 int ptrace_setregs(struct task_struct *child, struct user_pt_regs __user *data)
102 {
103 	struct pt_regs *regs;
104 	int i;
105 
106 	if (!access_ok(data, 38 * 8))
107 		return -EIO;
108 
109 	regs = task_pt_regs(child);
110 
111 	for (i = 0; i < 32; i++)
112 		__get_user(regs->regs[i], (__s64 __user *)&data->regs[i]);
113 	__get_user(regs->lo, (__s64 __user *)&data->lo);
114 	__get_user(regs->hi, (__s64 __user *)&data->hi);
115 	__get_user(regs->cp0_epc, (__s64 __user *)&data->cp0_epc);
116 
117 	/* badvaddr, status, and cause may not be written.  */
118 
119 	/* System call number may have been changed */
120 	mips_syscall_update_nr(child, regs);
121 
122 	return 0;
123 }
124 
125 int ptrace_get_watch_regs(struct task_struct *child,
126 			  struct pt_watch_regs __user *addr)
127 {
128 	enum pt_watch_style style;
129 	int i;
130 
131 	if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
132 		return -EIO;
133 	if (!access_ok(addr, sizeof(struct pt_watch_regs)))
134 		return -EIO;
135 
136 #ifdef CONFIG_32BIT
137 	style = pt_watch_style_mips32;
138 #define WATCH_STYLE mips32
139 #else
140 	style = pt_watch_style_mips64;
141 #define WATCH_STYLE mips64
142 #endif
143 
144 	__put_user(style, &addr->style);
145 	__put_user(boot_cpu_data.watch_reg_use_cnt,
146 		   &addr->WATCH_STYLE.num_valid);
147 	for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
148 		__put_user(child->thread.watch.mips3264.watchlo[i],
149 			   &addr->WATCH_STYLE.watchlo[i]);
150 		__put_user(child->thread.watch.mips3264.watchhi[i] &
151 				(MIPS_WATCHHI_MASK | MIPS_WATCHHI_IRW),
152 			   &addr->WATCH_STYLE.watchhi[i]);
153 		__put_user(boot_cpu_data.watch_reg_masks[i],
154 			   &addr->WATCH_STYLE.watch_masks[i]);
155 	}
156 	for (; i < 8; i++) {
157 		__put_user(0, &addr->WATCH_STYLE.watchlo[i]);
158 		__put_user(0, &addr->WATCH_STYLE.watchhi[i]);
159 		__put_user(0, &addr->WATCH_STYLE.watch_masks[i]);
160 	}
161 
162 	return 0;
163 }
164 
165 int ptrace_set_watch_regs(struct task_struct *child,
166 			  struct pt_watch_regs __user *addr)
167 {
168 	int i;
169 	int watch_active = 0;
170 	unsigned long lt[NUM_WATCH_REGS];
171 	u16 ht[NUM_WATCH_REGS];
172 
173 	if (!cpu_has_watch || boot_cpu_data.watch_reg_use_cnt == 0)
174 		return -EIO;
175 	if (!access_ok(addr, sizeof(struct pt_watch_regs)))
176 		return -EIO;
177 	/* Check the values. */
178 	for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
179 		__get_user(lt[i], &addr->WATCH_STYLE.watchlo[i]);
180 #ifdef CONFIG_32BIT
181 		if (lt[i] & __UA_LIMIT)
182 			return -EINVAL;
183 #else
184 		if (test_tsk_thread_flag(child, TIF_32BIT_ADDR)) {
185 			if (lt[i] & 0xffffffff80000000UL)
186 				return -EINVAL;
187 		} else {
188 			if (lt[i] & __UA_LIMIT)
189 				return -EINVAL;
190 		}
191 #endif
192 		__get_user(ht[i], &addr->WATCH_STYLE.watchhi[i]);
193 		if (ht[i] & ~MIPS_WATCHHI_MASK)
194 			return -EINVAL;
195 	}
196 	/* Install them. */
197 	for (i = 0; i < boot_cpu_data.watch_reg_use_cnt; i++) {
198 		if (lt[i] & MIPS_WATCHLO_IRW)
199 			watch_active = 1;
200 		child->thread.watch.mips3264.watchlo[i] = lt[i];
201 		/* Set the G bit. */
202 		child->thread.watch.mips3264.watchhi[i] = ht[i];
203 	}
204 
205 	if (watch_active)
206 		set_tsk_thread_flag(child, TIF_LOAD_WATCH);
207 	else
208 		clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
209 
210 	return 0;
211 }
212 
213 /* regset get/set implementations */
214 
215 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
216 
217 static int gpr32_get(struct task_struct *target,
218 		     const struct user_regset *regset,
219 		     struct membuf to)
220 {
221 	struct pt_regs *regs = task_pt_regs(target);
222 	u32 uregs[ELF_NGREG] = {};
223 
224 	mips_dump_regs32(uregs, regs);
225 	return membuf_write(&to, uregs, sizeof(uregs));
226 }
227 
228 static int gpr32_set(struct task_struct *target,
229 		     const struct user_regset *regset,
230 		     unsigned int pos, unsigned int count,
231 		     const void *kbuf, const void __user *ubuf)
232 {
233 	struct pt_regs *regs = task_pt_regs(target);
234 	u32 uregs[ELF_NGREG];
235 	unsigned start, num_regs, i;
236 	int err;
237 
238 	start = pos / sizeof(u32);
239 	num_regs = count / sizeof(u32);
240 
241 	if (start + num_regs > ELF_NGREG)
242 		return -EIO;
243 
244 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
245 				 sizeof(uregs));
246 	if (err)
247 		return err;
248 
249 	for (i = start; i < num_regs; i++) {
250 		/*
251 		 * Cast all values to signed here so that if this is a 64-bit
252 		 * kernel, the supplied 32-bit values will be sign extended.
253 		 */
254 		switch (i) {
255 		case MIPS32_EF_R1 ... MIPS32_EF_R25:
256 			/* k0/k1 are ignored. */
257 		case MIPS32_EF_R28 ... MIPS32_EF_R31:
258 			regs->regs[i - MIPS32_EF_R0] = (s32)uregs[i];
259 			break;
260 		case MIPS32_EF_LO:
261 			regs->lo = (s32)uregs[i];
262 			break;
263 		case MIPS32_EF_HI:
264 			regs->hi = (s32)uregs[i];
265 			break;
266 		case MIPS32_EF_CP0_EPC:
267 			regs->cp0_epc = (s32)uregs[i];
268 			break;
269 		}
270 	}
271 
272 	/* System call number may have been changed */
273 	mips_syscall_update_nr(target, regs);
274 
275 	return 0;
276 }
277 
278 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
279 
280 #ifdef CONFIG_64BIT
281 
282 static int gpr64_get(struct task_struct *target,
283 		     const struct user_regset *regset,
284 		     struct membuf to)
285 {
286 	struct pt_regs *regs = task_pt_regs(target);
287 	u64 uregs[ELF_NGREG] = {};
288 
289 	mips_dump_regs64(uregs, regs);
290 	return membuf_write(&to, uregs, sizeof(uregs));
291 }
292 
293 static int gpr64_set(struct task_struct *target,
294 		     const struct user_regset *regset,
295 		     unsigned int pos, unsigned int count,
296 		     const void *kbuf, const void __user *ubuf)
297 {
298 	struct pt_regs *regs = task_pt_regs(target);
299 	u64 uregs[ELF_NGREG];
300 	unsigned start, num_regs, i;
301 	int err;
302 
303 	start = pos / sizeof(u64);
304 	num_regs = count / sizeof(u64);
305 
306 	if (start + num_regs > ELF_NGREG)
307 		return -EIO;
308 
309 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
310 				 sizeof(uregs));
311 	if (err)
312 		return err;
313 
314 	for (i = start; i < num_regs; i++) {
315 		switch (i) {
316 		case MIPS64_EF_R1 ... MIPS64_EF_R25:
317 			/* k0/k1 are ignored. */
318 		case MIPS64_EF_R28 ... MIPS64_EF_R31:
319 			regs->regs[i - MIPS64_EF_R0] = uregs[i];
320 			break;
321 		case MIPS64_EF_LO:
322 			regs->lo = uregs[i];
323 			break;
324 		case MIPS64_EF_HI:
325 			regs->hi = uregs[i];
326 			break;
327 		case MIPS64_EF_CP0_EPC:
328 			regs->cp0_epc = uregs[i];
329 			break;
330 		}
331 	}
332 
333 	/* System call number may have been changed */
334 	mips_syscall_update_nr(target, regs);
335 
336 	return 0;
337 }
338 
339 #endif /* CONFIG_64BIT */
340 
341 
342 #ifdef CONFIG_MIPS_FP_SUPPORT
343 
344 /*
345  * Poke at FCSR according to its mask.  Set the Cause bits even
346  * if a corresponding Enable bit is set.  This will be noticed at
347  * the time the thread is switched to and SIGFPE thrown accordingly.
348  */
349 static void ptrace_setfcr31(struct task_struct *child, u32 value)
350 {
351 	u32 fcr31;
352 	u32 mask;
353 
354 	fcr31 = child->thread.fpu.fcr31;
355 	mask = boot_cpu_data.fpu_msk31;
356 	child->thread.fpu.fcr31 = (value & ~mask) | (fcr31 & mask);
357 }
358 
359 int ptrace_getfpregs(struct task_struct *child, __u32 __user *data)
360 {
361 	int i;
362 
363 	if (!access_ok(data, 33 * 8))
364 		return -EIO;
365 
366 	if (tsk_used_math(child)) {
367 		union fpureg *fregs = get_fpu_regs(child);
368 		for (i = 0; i < 32; i++)
369 			__put_user(get_fpr64(&fregs[i], 0),
370 				   i + (__u64 __user *)data);
371 	} else {
372 		for (i = 0; i < 32; i++)
373 			__put_user((__u64) -1, i + (__u64 __user *) data);
374 	}
375 
376 	__put_user(child->thread.fpu.fcr31, data + 64);
377 	__put_user(boot_cpu_data.fpu_id, data + 65);
378 
379 	return 0;
380 }
381 
382 int ptrace_setfpregs(struct task_struct *child, __u32 __user *data)
383 {
384 	union fpureg *fregs;
385 	u64 fpr_val;
386 	u32 value;
387 	int i;
388 
389 	if (!access_ok(data, 33 * 8))
390 		return -EIO;
391 
392 	init_fp_ctx(child);
393 	fregs = get_fpu_regs(child);
394 
395 	for (i = 0; i < 32; i++) {
396 		__get_user(fpr_val, i + (__u64 __user *)data);
397 		set_fpr64(&fregs[i], 0, fpr_val);
398 	}
399 
400 	__get_user(value, data + 64);
401 	ptrace_setfcr31(child, value);
402 
403 	/* FIR may not be written.  */
404 
405 	return 0;
406 }
407 
408 /*
409  * Copy the floating-point context to the supplied NT_PRFPREG buffer,
410  * !CONFIG_CPU_HAS_MSA variant.  FP context's general register slots
411  * correspond 1:1 to buffer slots.  Only general registers are copied.
412  */
413 static void fpr_get_fpa(struct task_struct *target,
414 		       struct membuf *to)
415 {
416 	membuf_write(to, &target->thread.fpu,
417 			NUM_FPU_REGS * sizeof(elf_fpreg_t));
418 }
419 
420 /*
421  * Copy the floating-point context to the supplied NT_PRFPREG buffer,
422  * CONFIG_CPU_HAS_MSA variant.  Only lower 64 bits of FP context's
423  * general register slots are copied to buffer slots.  Only general
424  * registers are copied.
425  */
426 static void fpr_get_msa(struct task_struct *target, struct membuf *to)
427 {
428 	unsigned int i;
429 
430 	BUILD_BUG_ON(sizeof(u64) != sizeof(elf_fpreg_t));
431 	for (i = 0; i < NUM_FPU_REGS; i++)
432 		membuf_store(to, get_fpr64(&target->thread.fpu.fpr[i], 0));
433 }
434 
435 /*
436  * Copy the floating-point context to the supplied NT_PRFPREG buffer.
437  * Choose the appropriate helper for general registers, and then copy
438  * the FCSR and FIR registers separately.
439  */
440 static int fpr_get(struct task_struct *target,
441 		   const struct user_regset *regset,
442 		   struct membuf to)
443 {
444 	if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
445 		fpr_get_fpa(target, &to);
446 	else
447 		fpr_get_msa(target, &to);
448 
449 	membuf_write(&to, &target->thread.fpu.fcr31, sizeof(u32));
450 	membuf_write(&to, &boot_cpu_data.fpu_id, sizeof(u32));
451 	return 0;
452 }
453 
454 /*
455  * Copy the supplied NT_PRFPREG buffer to the floating-point context,
456  * !CONFIG_CPU_HAS_MSA variant.   Buffer slots correspond 1:1 to FP
457  * context's general register slots.  Only general registers are copied.
458  */
459 static int fpr_set_fpa(struct task_struct *target,
460 		       unsigned int *pos, unsigned int *count,
461 		       const void **kbuf, const void __user **ubuf)
462 {
463 	return user_regset_copyin(pos, count, kbuf, ubuf,
464 				  &target->thread.fpu,
465 				  0, NUM_FPU_REGS * sizeof(elf_fpreg_t));
466 }
467 
468 /*
469  * Copy the supplied NT_PRFPREG buffer to the floating-point context,
470  * CONFIG_CPU_HAS_MSA variant.  Buffer slots are copied to lower 64
471  * bits only of FP context's general register slots.  Only general
472  * registers are copied.
473  */
474 static int fpr_set_msa(struct task_struct *target,
475 		       unsigned int *pos, unsigned int *count,
476 		       const void **kbuf, const void __user **ubuf)
477 {
478 	unsigned int i;
479 	u64 fpr_val;
480 	int err;
481 
482 	BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
483 	for (i = 0; i < NUM_FPU_REGS && *count > 0; i++) {
484 		err = user_regset_copyin(pos, count, kbuf, ubuf,
485 					 &fpr_val, i * sizeof(elf_fpreg_t),
486 					 (i + 1) * sizeof(elf_fpreg_t));
487 		if (err)
488 			return err;
489 		set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
490 	}
491 
492 	return 0;
493 }
494 
495 /*
496  * Copy the supplied NT_PRFPREG buffer to the floating-point context.
497  * Choose the appropriate helper for general registers, and then copy
498  * the FCSR register separately.  Ignore the incoming FIR register
499  * contents though, as the register is read-only.
500  *
501  * We optimize for the case where `count % sizeof(elf_fpreg_t) == 0',
502  * which is supposed to have been guaranteed by the kernel before
503  * calling us, e.g. in `ptrace_regset'.  We enforce that requirement,
504  * so that we can safely avoid preinitializing temporaries for
505  * partial register writes.
506  */
507 static int fpr_set(struct task_struct *target,
508 		   const struct user_regset *regset,
509 		   unsigned int pos, unsigned int count,
510 		   const void *kbuf, const void __user *ubuf)
511 {
512 	const int fcr31_pos = NUM_FPU_REGS * sizeof(elf_fpreg_t);
513 	const int fir_pos = fcr31_pos + sizeof(u32);
514 	u32 fcr31;
515 	int err;
516 
517 	BUG_ON(count % sizeof(elf_fpreg_t));
518 
519 	if (pos + count > sizeof(elf_fpregset_t))
520 		return -EIO;
521 
522 	init_fp_ctx(target);
523 
524 	if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))
525 		err = fpr_set_fpa(target, &pos, &count, &kbuf, &ubuf);
526 	else
527 		err = fpr_set_msa(target, &pos, &count, &kbuf, &ubuf);
528 	if (err)
529 		return err;
530 
531 	if (count > 0) {
532 		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
533 					 &fcr31,
534 					 fcr31_pos, fcr31_pos + sizeof(u32));
535 		if (err)
536 			return err;
537 
538 		ptrace_setfcr31(target, fcr31);
539 	}
540 
541 	if (count > 0) {
542 		user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
543 					  fir_pos, fir_pos + sizeof(u32));
544 		return 0;
545 	}
546 
547 	return err;
548 }
549 
550 /* Copy the FP mode setting to the supplied NT_MIPS_FP_MODE buffer.  */
551 static int fp_mode_get(struct task_struct *target,
552 		       const struct user_regset *regset,
553 		       struct membuf to)
554 {
555 	return membuf_store(&to, (int)mips_get_process_fp_mode(target));
556 }
557 
558 /*
559  * Copy the supplied NT_MIPS_FP_MODE buffer to the FP mode setting.
560  *
561  * We optimize for the case where `count % sizeof(int) == 0', which
562  * is supposed to have been guaranteed by the kernel before calling
563  * us, e.g. in `ptrace_regset'.  We enforce that requirement, so
564  * that we can safely avoid preinitializing temporaries for partial
565  * mode writes.
566  */
567 static int fp_mode_set(struct task_struct *target,
568 		       const struct user_regset *regset,
569 		       unsigned int pos, unsigned int count,
570 		       const void *kbuf, const void __user *ubuf)
571 {
572 	int fp_mode;
573 	int err;
574 
575 	BUG_ON(count % sizeof(int));
576 
577 	if (pos + count > sizeof(fp_mode))
578 		return -EIO;
579 
580 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &fp_mode, 0,
581 				 sizeof(fp_mode));
582 	if (err)
583 		return err;
584 
585 	if (count > 0)
586 		err = mips_set_process_fp_mode(target, fp_mode);
587 
588 	return err;
589 }
590 
591 #endif /* CONFIG_MIPS_FP_SUPPORT */
592 
593 #ifdef CONFIG_CPU_HAS_MSA
594 
595 struct msa_control_regs {
596 	unsigned int fir;
597 	unsigned int fcsr;
598 	unsigned int msair;
599 	unsigned int msacsr;
600 };
601 
602 static void copy_pad_fprs(struct task_struct *target,
603 			 const struct user_regset *regset,
604 			 struct membuf *to,
605 			 unsigned int live_sz)
606 {
607 	int i, j;
608 	unsigned long long fill = ~0ull;
609 	unsigned int cp_sz, pad_sz;
610 
611 	cp_sz = min(regset->size, live_sz);
612 	pad_sz = regset->size - cp_sz;
613 	WARN_ON(pad_sz % sizeof(fill));
614 
615 	for (i = 0; i < NUM_FPU_REGS; i++) {
616 		membuf_write(to, &target->thread.fpu.fpr[i], cp_sz);
617 		for (j = 0; j < (pad_sz / sizeof(fill)); j++)
618 			membuf_store(to, fill);
619 	}
620 }
621 
622 static int msa_get(struct task_struct *target,
623 		   const struct user_regset *regset,
624 		   struct membuf to)
625 {
626 	const unsigned int wr_size = NUM_FPU_REGS * regset->size;
627 	const struct msa_control_regs ctrl_regs = {
628 		.fir = boot_cpu_data.fpu_id,
629 		.fcsr = target->thread.fpu.fcr31,
630 		.msair = boot_cpu_data.msa_id,
631 		.msacsr = target->thread.fpu.msacsr,
632 	};
633 
634 	if (!tsk_used_math(target)) {
635 		/* The task hasn't used FP or MSA, fill with 0xff */
636 		copy_pad_fprs(target, regset, &to, 0);
637 	} else if (!test_tsk_thread_flag(target, TIF_MSA_CTX_LIVE)) {
638 		/* Copy scalar FP context, fill the rest with 0xff */
639 		copy_pad_fprs(target, regset, &to, 8);
640 	} else if (sizeof(target->thread.fpu.fpr[0]) == regset->size) {
641 		/* Trivially copy the vector registers */
642 		membuf_write(&to, &target->thread.fpu.fpr, wr_size);
643 	} else {
644 		/* Copy as much context as possible, fill the rest with 0xff */
645 		copy_pad_fprs(target, regset, &to,
646 				sizeof(target->thread.fpu.fpr[0]));
647 	}
648 
649 	return membuf_write(&to, &ctrl_regs, sizeof(ctrl_regs));
650 }
651 
652 static int msa_set(struct task_struct *target,
653 		   const struct user_regset *regset,
654 		   unsigned int pos, unsigned int count,
655 		   const void *kbuf, const void __user *ubuf)
656 {
657 	const unsigned int wr_size = NUM_FPU_REGS * regset->size;
658 	struct msa_control_regs ctrl_regs;
659 	unsigned int cp_sz;
660 	int i, err, start;
661 
662 	init_fp_ctx(target);
663 
664 	if (sizeof(target->thread.fpu.fpr[0]) == regset->size) {
665 		/* Trivially copy the vector registers */
666 		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
667 					 &target->thread.fpu.fpr,
668 					 0, wr_size);
669 	} else {
670 		/* Copy as much context as possible */
671 		cp_sz = min_t(unsigned int, regset->size,
672 			      sizeof(target->thread.fpu.fpr[0]));
673 
674 		i = start = err = 0;
675 		for (; i < NUM_FPU_REGS; i++, start += regset->size) {
676 			err |= user_regset_copyin(&pos, &count, &kbuf, &ubuf,
677 						  &target->thread.fpu.fpr[i],
678 						  start, start + cp_sz);
679 		}
680 	}
681 
682 	if (!err)
683 		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl_regs,
684 					 wr_size, wr_size + sizeof(ctrl_regs));
685 	if (!err) {
686 		target->thread.fpu.fcr31 = ctrl_regs.fcsr & ~FPU_CSR_ALL_X;
687 		target->thread.fpu.msacsr = ctrl_regs.msacsr & ~MSA_CSR_CAUSEF;
688 	}
689 
690 	return err;
691 }
692 
693 #endif /* CONFIG_CPU_HAS_MSA */
694 
695 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
696 
697 /*
698  * Copy the DSP context to the supplied 32-bit NT_MIPS_DSP buffer.
699  */
700 static int dsp32_get(struct task_struct *target,
701 		     const struct user_regset *regset,
702 		     struct membuf to)
703 {
704 	u32 dspregs[NUM_DSP_REGS + 1];
705 	unsigned int i;
706 
707 	BUG_ON(to.left % sizeof(u32));
708 
709 	if (!cpu_has_dsp)
710 		return -EIO;
711 
712 	for (i = 0; i < NUM_DSP_REGS; i++)
713 		dspregs[i] = target->thread.dsp.dspr[i];
714 	dspregs[NUM_DSP_REGS] = target->thread.dsp.dspcontrol;
715 	return membuf_write(&to, dspregs, sizeof(dspregs));
716 }
717 
718 /*
719  * Copy the supplied 32-bit NT_MIPS_DSP buffer to the DSP context.
720  */
721 static int dsp32_set(struct task_struct *target,
722 		     const struct user_regset *regset,
723 		     unsigned int pos, unsigned int count,
724 		     const void *kbuf, const void __user *ubuf)
725 {
726 	unsigned int start, num_regs, i;
727 	u32 dspregs[NUM_DSP_REGS + 1];
728 	int err;
729 
730 	BUG_ON(count % sizeof(u32));
731 
732 	if (!cpu_has_dsp)
733 		return -EIO;
734 
735 	start = pos / sizeof(u32);
736 	num_regs = count / sizeof(u32);
737 
738 	if (start + num_regs > NUM_DSP_REGS + 1)
739 		return -EIO;
740 
741 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, dspregs, 0,
742 				 sizeof(dspregs));
743 	if (err)
744 		return err;
745 
746 	for (i = start; i < num_regs; i++)
747 		switch (i) {
748 		case 0 ... NUM_DSP_REGS - 1:
749 			target->thread.dsp.dspr[i] = (s32)dspregs[i];
750 			break;
751 		case NUM_DSP_REGS:
752 			target->thread.dsp.dspcontrol = (s32)dspregs[i];
753 			break;
754 		}
755 
756 	return 0;
757 }
758 
759 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
760 
761 #ifdef CONFIG_64BIT
762 
763 /*
764  * Copy the DSP context to the supplied 64-bit NT_MIPS_DSP buffer.
765  */
766 static int dsp64_get(struct task_struct *target,
767 		     const struct user_regset *regset,
768 		     struct membuf to)
769 {
770 	u64 dspregs[NUM_DSP_REGS + 1];
771 	unsigned int i;
772 
773 	BUG_ON(to.left % sizeof(u64));
774 
775 	if (!cpu_has_dsp)
776 		return -EIO;
777 
778 	for (i = 0; i < NUM_DSP_REGS; i++)
779 		dspregs[i] = target->thread.dsp.dspr[i];
780 	dspregs[NUM_DSP_REGS] = target->thread.dsp.dspcontrol;
781 	return membuf_write(&to, dspregs, sizeof(dspregs));
782 }
783 
784 /*
785  * Copy the supplied 64-bit NT_MIPS_DSP buffer to the DSP context.
786  */
787 static int dsp64_set(struct task_struct *target,
788 		     const struct user_regset *regset,
789 		     unsigned int pos, unsigned int count,
790 		     const void *kbuf, const void __user *ubuf)
791 {
792 	unsigned int start, num_regs, i;
793 	u64 dspregs[NUM_DSP_REGS + 1];
794 	int err;
795 
796 	BUG_ON(count % sizeof(u64));
797 
798 	if (!cpu_has_dsp)
799 		return -EIO;
800 
801 	start = pos / sizeof(u64);
802 	num_regs = count / sizeof(u64);
803 
804 	if (start + num_regs > NUM_DSP_REGS + 1)
805 		return -EIO;
806 
807 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, dspregs, 0,
808 				 sizeof(dspregs));
809 	if (err)
810 		return err;
811 
812 	for (i = start; i < num_regs; i++)
813 		switch (i) {
814 		case 0 ... NUM_DSP_REGS - 1:
815 			target->thread.dsp.dspr[i] = dspregs[i];
816 			break;
817 		case NUM_DSP_REGS:
818 			target->thread.dsp.dspcontrol = dspregs[i];
819 			break;
820 		}
821 
822 	return 0;
823 }
824 
825 #endif /* CONFIG_64BIT */
826 
827 /*
828  * Determine whether the DSP context is present.
829  */
830 static int dsp_active(struct task_struct *target,
831 		      const struct user_regset *regset)
832 {
833 	return cpu_has_dsp ? NUM_DSP_REGS + 1 : -ENODEV;
834 }
835 
836 enum mips_regset {
837 	REGSET_GPR,
838 	REGSET_DSP,
839 #ifdef CONFIG_MIPS_FP_SUPPORT
840 	REGSET_FPR,
841 	REGSET_FP_MODE,
842 #endif
843 #ifdef CONFIG_CPU_HAS_MSA
844 	REGSET_MSA,
845 #endif
846 };
847 
848 struct pt_regs_offset {
849 	const char *name;
850 	int offset;
851 };
852 
853 #define REG_OFFSET_NAME(reg, r) {					\
854 	.name = #reg,							\
855 	.offset = offsetof(struct pt_regs, r)				\
856 }
857 
858 #define REG_OFFSET_END {						\
859 	.name = NULL,							\
860 	.offset = 0							\
861 }
862 
863 static const struct pt_regs_offset regoffset_table[] = {
864 	REG_OFFSET_NAME(r0, regs[0]),
865 	REG_OFFSET_NAME(r1, regs[1]),
866 	REG_OFFSET_NAME(r2, regs[2]),
867 	REG_OFFSET_NAME(r3, regs[3]),
868 	REG_OFFSET_NAME(r4, regs[4]),
869 	REG_OFFSET_NAME(r5, regs[5]),
870 	REG_OFFSET_NAME(r6, regs[6]),
871 	REG_OFFSET_NAME(r7, regs[7]),
872 	REG_OFFSET_NAME(r8, regs[8]),
873 	REG_OFFSET_NAME(r9, regs[9]),
874 	REG_OFFSET_NAME(r10, regs[10]),
875 	REG_OFFSET_NAME(r11, regs[11]),
876 	REG_OFFSET_NAME(r12, regs[12]),
877 	REG_OFFSET_NAME(r13, regs[13]),
878 	REG_OFFSET_NAME(r14, regs[14]),
879 	REG_OFFSET_NAME(r15, regs[15]),
880 	REG_OFFSET_NAME(r16, regs[16]),
881 	REG_OFFSET_NAME(r17, regs[17]),
882 	REG_OFFSET_NAME(r18, regs[18]),
883 	REG_OFFSET_NAME(r19, regs[19]),
884 	REG_OFFSET_NAME(r20, regs[20]),
885 	REG_OFFSET_NAME(r21, regs[21]),
886 	REG_OFFSET_NAME(r22, regs[22]),
887 	REG_OFFSET_NAME(r23, regs[23]),
888 	REG_OFFSET_NAME(r24, regs[24]),
889 	REG_OFFSET_NAME(r25, regs[25]),
890 	REG_OFFSET_NAME(r26, regs[26]),
891 	REG_OFFSET_NAME(r27, regs[27]),
892 	REG_OFFSET_NAME(r28, regs[28]),
893 	REG_OFFSET_NAME(r29, regs[29]),
894 	REG_OFFSET_NAME(r30, regs[30]),
895 	REG_OFFSET_NAME(r31, regs[31]),
896 	REG_OFFSET_NAME(c0_status, cp0_status),
897 	REG_OFFSET_NAME(hi, hi),
898 	REG_OFFSET_NAME(lo, lo),
899 #ifdef CONFIG_CPU_HAS_SMARTMIPS
900 	REG_OFFSET_NAME(acx, acx),
901 #endif
902 	REG_OFFSET_NAME(c0_badvaddr, cp0_badvaddr),
903 	REG_OFFSET_NAME(c0_cause, cp0_cause),
904 	REG_OFFSET_NAME(c0_epc, cp0_epc),
905 #ifdef CONFIG_CPU_CAVIUM_OCTEON
906 	REG_OFFSET_NAME(mpl0, mpl[0]),
907 	REG_OFFSET_NAME(mpl1, mpl[1]),
908 	REG_OFFSET_NAME(mpl2, mpl[2]),
909 	REG_OFFSET_NAME(mtp0, mtp[0]),
910 	REG_OFFSET_NAME(mtp1, mtp[1]),
911 	REG_OFFSET_NAME(mtp2, mtp[2]),
912 #endif
913 	REG_OFFSET_END,
914 };
915 
916 /**
917  * regs_query_register_offset() - query register offset from its name
918  * @name:       the name of a register
919  *
920  * regs_query_register_offset() returns the offset of a register in struct
921  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
922  */
923 int regs_query_register_offset(const char *name)
924 {
925         const struct pt_regs_offset *roff;
926         for (roff = regoffset_table; roff->name != NULL; roff++)
927                 if (!strcmp(roff->name, name))
928                         return roff->offset;
929         return -EINVAL;
930 }
931 
932 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
933 
934 static const struct user_regset mips_regsets[] = {
935 	[REGSET_GPR] = {
936 		.core_note_type	= NT_PRSTATUS,
937 		.n		= ELF_NGREG,
938 		.size		= sizeof(unsigned int),
939 		.align		= sizeof(unsigned int),
940 		.regset_get		= gpr32_get,
941 		.set		= gpr32_set,
942 	},
943 	[REGSET_DSP] = {
944 		.core_note_type	= NT_MIPS_DSP,
945 		.n		= NUM_DSP_REGS + 1,
946 		.size		= sizeof(u32),
947 		.align		= sizeof(u32),
948 		.regset_get		= dsp32_get,
949 		.set		= dsp32_set,
950 		.active		= dsp_active,
951 	},
952 #ifdef CONFIG_MIPS_FP_SUPPORT
953 	[REGSET_FPR] = {
954 		.core_note_type	= NT_PRFPREG,
955 		.n		= ELF_NFPREG,
956 		.size		= sizeof(elf_fpreg_t),
957 		.align		= sizeof(elf_fpreg_t),
958 		.regset_get		= fpr_get,
959 		.set		= fpr_set,
960 	},
961 	[REGSET_FP_MODE] = {
962 		.core_note_type	= NT_MIPS_FP_MODE,
963 		.n		= 1,
964 		.size		= sizeof(int),
965 		.align		= sizeof(int),
966 		.regset_get		= fp_mode_get,
967 		.set		= fp_mode_set,
968 	},
969 #endif
970 #ifdef CONFIG_CPU_HAS_MSA
971 	[REGSET_MSA] = {
972 		.core_note_type	= NT_MIPS_MSA,
973 		.n		= NUM_FPU_REGS + 1,
974 		.size		= 16,
975 		.align		= 16,
976 		.regset_get		= msa_get,
977 		.set		= msa_set,
978 	},
979 #endif
980 };
981 
982 static const struct user_regset_view user_mips_view = {
983 	.name		= "mips",
984 	.e_machine	= ELF_ARCH,
985 	.ei_osabi	= ELF_OSABI,
986 	.regsets	= mips_regsets,
987 	.n		= ARRAY_SIZE(mips_regsets),
988 };
989 
990 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
991 
992 #ifdef CONFIG_64BIT
993 
994 static const struct user_regset mips64_regsets[] = {
995 	[REGSET_GPR] = {
996 		.core_note_type	= NT_PRSTATUS,
997 		.n		= ELF_NGREG,
998 		.size		= sizeof(unsigned long),
999 		.align		= sizeof(unsigned long),
1000 		.regset_get		= gpr64_get,
1001 		.set		= gpr64_set,
1002 	},
1003 	[REGSET_DSP] = {
1004 		.core_note_type	= NT_MIPS_DSP,
1005 		.n		= NUM_DSP_REGS + 1,
1006 		.size		= sizeof(u64),
1007 		.align		= sizeof(u64),
1008 		.regset_get		= dsp64_get,
1009 		.set		= dsp64_set,
1010 		.active		= dsp_active,
1011 	},
1012 #ifdef CONFIG_MIPS_FP_SUPPORT
1013 	[REGSET_FP_MODE] = {
1014 		.core_note_type	= NT_MIPS_FP_MODE,
1015 		.n		= 1,
1016 		.size		= sizeof(int),
1017 		.align		= sizeof(int),
1018 		.regset_get		= fp_mode_get,
1019 		.set		= fp_mode_set,
1020 	},
1021 	[REGSET_FPR] = {
1022 		.core_note_type	= NT_PRFPREG,
1023 		.n		= ELF_NFPREG,
1024 		.size		= sizeof(elf_fpreg_t),
1025 		.align		= sizeof(elf_fpreg_t),
1026 		.regset_get		= fpr_get,
1027 		.set		= fpr_set,
1028 	},
1029 #endif
1030 #ifdef CONFIG_CPU_HAS_MSA
1031 	[REGSET_MSA] = {
1032 		.core_note_type	= NT_MIPS_MSA,
1033 		.n		= NUM_FPU_REGS + 1,
1034 		.size		= 16,
1035 		.align		= 16,
1036 		.regset_get		= msa_get,
1037 		.set		= msa_set,
1038 	},
1039 #endif
1040 };
1041 
1042 static const struct user_regset_view user_mips64_view = {
1043 	.name		= "mips64",
1044 	.e_machine	= ELF_ARCH,
1045 	.ei_osabi	= ELF_OSABI,
1046 	.regsets	= mips64_regsets,
1047 	.n		= ARRAY_SIZE(mips64_regsets),
1048 };
1049 
1050 #ifdef CONFIG_MIPS32_N32
1051 
1052 static const struct user_regset_view user_mipsn32_view = {
1053 	.name		= "mipsn32",
1054 	.e_flags	= EF_MIPS_ABI2,
1055 	.e_machine	= ELF_ARCH,
1056 	.ei_osabi	= ELF_OSABI,
1057 	.regsets	= mips64_regsets,
1058 	.n		= ARRAY_SIZE(mips64_regsets),
1059 };
1060 
1061 #endif /* CONFIG_MIPS32_N32 */
1062 
1063 #endif /* CONFIG_64BIT */
1064 
1065 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
1066 {
1067 #ifdef CONFIG_32BIT
1068 	return &user_mips_view;
1069 #else
1070 #ifdef CONFIG_MIPS32_O32
1071 	if (test_tsk_thread_flag(task, TIF_32BIT_REGS))
1072 		return &user_mips_view;
1073 #endif
1074 #ifdef CONFIG_MIPS32_N32
1075 	if (test_tsk_thread_flag(task, TIF_32BIT_ADDR))
1076 		return &user_mipsn32_view;
1077 #endif
1078 	return &user_mips64_view;
1079 #endif
1080 }
1081 
1082 long arch_ptrace(struct task_struct *child, long request,
1083 		 unsigned long addr, unsigned long data)
1084 {
1085 	int ret;
1086 	void __user *addrp = (void __user *) addr;
1087 	void __user *datavp = (void __user *) data;
1088 	unsigned long __user *datalp = (void __user *) data;
1089 
1090 	switch (request) {
1091 	/* when I and D space are separate, these will need to be fixed. */
1092 	case PTRACE_PEEKTEXT: /* read word at location addr. */
1093 	case PTRACE_PEEKDATA:
1094 		ret = generic_ptrace_peekdata(child, addr, data);
1095 		break;
1096 
1097 	/* Read the word at location addr in the USER area. */
1098 	case PTRACE_PEEKUSR: {
1099 		struct pt_regs *regs;
1100 		unsigned long tmp = 0;
1101 
1102 		regs = task_pt_regs(child);
1103 		ret = 0;  /* Default return value. */
1104 
1105 		switch (addr) {
1106 		case 0 ... 31:
1107 			tmp = regs->regs[addr];
1108 			break;
1109 #ifdef CONFIG_MIPS_FP_SUPPORT
1110 		case FPR_BASE ... FPR_BASE + 31: {
1111 			union fpureg *fregs;
1112 
1113 			if (!tsk_used_math(child)) {
1114 				/* FP not yet used */
1115 				tmp = -1;
1116 				break;
1117 			}
1118 			fregs = get_fpu_regs(child);
1119 
1120 #ifdef CONFIG_32BIT
1121 			if (test_tsk_thread_flag(child, TIF_32BIT_FPREGS)) {
1122 				/*
1123 				 * The odd registers are actually the high
1124 				 * order bits of the values stored in the even
1125 				 * registers.
1126 				 */
1127 				tmp = get_fpr32(&fregs[(addr & ~1) - FPR_BASE],
1128 						addr & 1);
1129 				break;
1130 			}
1131 #endif
1132 			tmp = get_fpr64(&fregs[addr - FPR_BASE], 0);
1133 			break;
1134 		}
1135 		case FPC_CSR:
1136 			tmp = child->thread.fpu.fcr31;
1137 			break;
1138 		case FPC_EIR:
1139 			/* implementation / version register */
1140 			tmp = boot_cpu_data.fpu_id;
1141 			break;
1142 #endif
1143 		case PC:
1144 			tmp = regs->cp0_epc;
1145 			break;
1146 		case CAUSE:
1147 			tmp = regs->cp0_cause;
1148 			break;
1149 		case BADVADDR:
1150 			tmp = regs->cp0_badvaddr;
1151 			break;
1152 		case MMHI:
1153 			tmp = regs->hi;
1154 			break;
1155 		case MMLO:
1156 			tmp = regs->lo;
1157 			break;
1158 #ifdef CONFIG_CPU_HAS_SMARTMIPS
1159 		case ACX:
1160 			tmp = regs->acx;
1161 			break;
1162 #endif
1163 		case DSP_BASE ... DSP_BASE + 5: {
1164 			dspreg_t *dregs;
1165 
1166 			if (!cpu_has_dsp) {
1167 				tmp = 0;
1168 				ret = -EIO;
1169 				goto out;
1170 			}
1171 			dregs = __get_dsp_regs(child);
1172 			tmp = dregs[addr - DSP_BASE];
1173 			break;
1174 		}
1175 		case DSP_CONTROL:
1176 			if (!cpu_has_dsp) {
1177 				tmp = 0;
1178 				ret = -EIO;
1179 				goto out;
1180 			}
1181 			tmp = child->thread.dsp.dspcontrol;
1182 			break;
1183 		default:
1184 			tmp = 0;
1185 			ret = -EIO;
1186 			goto out;
1187 		}
1188 		ret = put_user(tmp, datalp);
1189 		break;
1190 	}
1191 
1192 	/* when I and D space are separate, this will have to be fixed. */
1193 	case PTRACE_POKETEXT: /* write the word at location addr. */
1194 	case PTRACE_POKEDATA:
1195 		ret = generic_ptrace_pokedata(child, addr, data);
1196 		break;
1197 
1198 	case PTRACE_POKEUSR: {
1199 		struct pt_regs *regs;
1200 		ret = 0;
1201 		regs = task_pt_regs(child);
1202 
1203 		switch (addr) {
1204 		case 0 ... 31:
1205 			regs->regs[addr] = data;
1206 			/* System call number may have been changed */
1207 			if (addr == 2)
1208 				mips_syscall_update_nr(child, regs);
1209 			else if (addr == 4 &&
1210 				 mips_syscall_is_indirect(child, regs))
1211 				mips_syscall_update_nr(child, regs);
1212 			break;
1213 #ifdef CONFIG_MIPS_FP_SUPPORT
1214 		case FPR_BASE ... FPR_BASE + 31: {
1215 			union fpureg *fregs = get_fpu_regs(child);
1216 
1217 			init_fp_ctx(child);
1218 #ifdef CONFIG_32BIT
1219 			if (test_tsk_thread_flag(child, TIF_32BIT_FPREGS)) {
1220 				/*
1221 				 * The odd registers are actually the high
1222 				 * order bits of the values stored in the even
1223 				 * registers.
1224 				 */
1225 				set_fpr32(&fregs[(addr & ~1) - FPR_BASE],
1226 					  addr & 1, data);
1227 				break;
1228 			}
1229 #endif
1230 			set_fpr64(&fregs[addr - FPR_BASE], 0, data);
1231 			break;
1232 		}
1233 		case FPC_CSR:
1234 			init_fp_ctx(child);
1235 			ptrace_setfcr31(child, data);
1236 			break;
1237 #endif
1238 		case PC:
1239 			regs->cp0_epc = data;
1240 			break;
1241 		case MMHI:
1242 			regs->hi = data;
1243 			break;
1244 		case MMLO:
1245 			regs->lo = data;
1246 			break;
1247 #ifdef CONFIG_CPU_HAS_SMARTMIPS
1248 		case ACX:
1249 			regs->acx = data;
1250 			break;
1251 #endif
1252 		case DSP_BASE ... DSP_BASE + 5: {
1253 			dspreg_t *dregs;
1254 
1255 			if (!cpu_has_dsp) {
1256 				ret = -EIO;
1257 				break;
1258 			}
1259 
1260 			dregs = __get_dsp_regs(child);
1261 			dregs[addr - DSP_BASE] = data;
1262 			break;
1263 		}
1264 		case DSP_CONTROL:
1265 			if (!cpu_has_dsp) {
1266 				ret = -EIO;
1267 				break;
1268 			}
1269 			child->thread.dsp.dspcontrol = data;
1270 			break;
1271 		default:
1272 			/* The rest are not allowed. */
1273 			ret = -EIO;
1274 			break;
1275 		}
1276 		break;
1277 		}
1278 
1279 	case PTRACE_GETREGS:
1280 		ret = ptrace_getregs(child, datavp);
1281 		break;
1282 
1283 	case PTRACE_SETREGS:
1284 		ret = ptrace_setregs(child, datavp);
1285 		break;
1286 
1287 #ifdef CONFIG_MIPS_FP_SUPPORT
1288 	case PTRACE_GETFPREGS:
1289 		ret = ptrace_getfpregs(child, datavp);
1290 		break;
1291 
1292 	case PTRACE_SETFPREGS:
1293 		ret = ptrace_setfpregs(child, datavp);
1294 		break;
1295 #endif
1296 	case PTRACE_GET_THREAD_AREA:
1297 		ret = put_user(task_thread_info(child)->tp_value, datalp);
1298 		break;
1299 
1300 	case PTRACE_GET_WATCH_REGS:
1301 		ret = ptrace_get_watch_regs(child, addrp);
1302 		break;
1303 
1304 	case PTRACE_SET_WATCH_REGS:
1305 		ret = ptrace_set_watch_regs(child, addrp);
1306 		break;
1307 
1308 	default:
1309 		ret = ptrace_request(child, request, addr, data);
1310 		break;
1311 	}
1312  out:
1313 	return ret;
1314 }
1315 
1316 /*
1317  * Notification of system call entry/exit
1318  * - triggered by current->work.syscall_trace
1319  */
1320 asmlinkage long syscall_trace_enter(struct pt_regs *regs)
1321 {
1322 	user_exit();
1323 
1324 	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
1325 		if (ptrace_report_syscall_entry(regs))
1326 			return -1;
1327 	}
1328 
1329 #ifdef CONFIG_SECCOMP
1330 	if (unlikely(test_thread_flag(TIF_SECCOMP))) {
1331 		int ret, i;
1332 		struct seccomp_data sd;
1333 		unsigned long args[6];
1334 
1335 		sd.nr = current_thread_info()->syscall;
1336 		sd.arch = syscall_get_arch(current);
1337 		syscall_get_arguments(current, regs, args);
1338 		for (i = 0; i < 6; i++)
1339 			sd.args[i] = args[i];
1340 		sd.instruction_pointer = KSTK_EIP(current);
1341 
1342 		ret = __secure_computing(&sd);
1343 		if (ret == -1)
1344 			return ret;
1345 	}
1346 #endif
1347 
1348 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1349 		trace_sys_enter(regs, regs->regs[2]);
1350 
1351 	audit_syscall_entry(current_thread_info()->syscall,
1352 			    regs->regs[4], regs->regs[5],
1353 			    regs->regs[6], regs->regs[7]);
1354 
1355 	/*
1356 	 * Negative syscall numbers are mistaken for rejected syscalls, but
1357 	 * won't have had the return value set appropriately, so we do so now.
1358 	 */
1359 	if (current_thread_info()->syscall < 0)
1360 		syscall_set_return_value(current, regs, -ENOSYS, 0);
1361 	return current_thread_info()->syscall;
1362 }
1363 
1364 /*
1365  * Notification of system call entry/exit
1366  * - triggered by current->work.syscall_trace
1367  */
1368 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1369 {
1370         /*
1371 	 * We may come here right after calling schedule_user()
1372 	 * or do_notify_resume(), in which case we can be in RCU
1373 	 * user mode.
1374 	 */
1375 	user_exit();
1376 
1377 	audit_syscall_exit(regs);
1378 
1379 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1380 		trace_sys_exit(regs, regs_return_value(regs));
1381 
1382 	if (test_thread_flag(TIF_SYSCALL_TRACE))
1383 		ptrace_report_syscall_exit(regs, 0);
1384 
1385 	user_enter();
1386 }
1387