xref: /openbmc/linux/arch/mips/kernel/ptrace.c (revision 8e694cd2)
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/mm.h>
23 #include <linux/errno.h>
24 #include <linux/ptrace.h>
25 #include <linux/regset.h>
26 #include <linux/smp.h>
27 #include <linux/security.h>
28 #include <linux/stddef.h>
29 #include <linux/tracehook.h>
30 #include <linux/audit.h>
31 #include <linux/seccomp.h>
32 #include <linux/ftrace.h>
33 
34 #include <asm/byteorder.h>
35 #include <asm/cpu.h>
36 #include <asm/cpu-info.h>
37 #include <asm/dsp.h>
38 #include <asm/fpu.h>
39 #include <asm/mipsregs.h>
40 #include <asm/mipsmtregs.h>
41 #include <asm/pgtable.h>
42 #include <asm/page.h>
43 #include <asm/syscall.h>
44 #include <asm/uaccess.h>
45 #include <asm/bootinfo.h>
46 #include <asm/reg.h>
47 
48 #define CREATE_TRACE_POINTS
49 #include <trace/events/syscalls.h>
50 
51 static void init_fp_ctx(struct task_struct *target)
52 {
53 	/* If FP has been used then the target already has context */
54 	if (tsk_used_math(target))
55 		return;
56 
57 	/* Begin with data registers set to all 1s... */
58 	memset(&target->thread.fpu.fpr, ~0, sizeof(target->thread.fpu.fpr));
59 
60 	/* FCSR has been preset by `mips_set_personality_nan'.  */
61 
62 	/*
63 	 * Record that the target has "used" math, such that the context
64 	 * just initialised, and any modifications made by the caller,
65 	 * aren't discarded.
66 	 */
67 	set_stopped_child_used_math(target);
68 }
69 
70 /*
71  * Called by kernel/ptrace.c when detaching..
72  *
73  * Make sure single step bits etc are not set.
74  */
75 void ptrace_disable(struct task_struct *child)
76 {
77 	/* Don't load the watchpoint registers for the ex-child. */
78 	clear_tsk_thread_flag(child, TIF_LOAD_WATCH);
79 }
80 
81 /*
82  * Poke at FCSR according to its mask.  Don't set the cause bits as
83  * this is currently not handled correctly in FP context restoration
84  * and will cause an oops if a corresponding enable bit is set.
85  */
86 static void ptrace_setfcr31(struct task_struct *child, u32 value)
87 {
88 	u32 fcr31;
89 	u32 mask;
90 
91 	value &= ~FPU_CSR_ALL_X;
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 	unsigned i;
299 
300 	for (i = MIPS32_EF_R1; i <= MIPS32_EF_R31; i++) {
301 		/* k0/k1 are copied as zero. */
302 		if (i == MIPS32_EF_R26 || i == MIPS32_EF_R27)
303 			continue;
304 
305 		uregs[i] = regs->regs[i - MIPS32_EF_R0];
306 	}
307 
308 	uregs[MIPS32_EF_LO] = regs->lo;
309 	uregs[MIPS32_EF_HI] = regs->hi;
310 	uregs[MIPS32_EF_CP0_EPC] = regs->cp0_epc;
311 	uregs[MIPS32_EF_CP0_BADVADDR] = regs->cp0_badvaddr;
312 	uregs[MIPS32_EF_CP0_STATUS] = regs->cp0_status;
313 	uregs[MIPS32_EF_CP0_CAUSE] = regs->cp0_cause;
314 
315 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
316 				   sizeof(uregs));
317 }
318 
319 static int gpr32_set(struct task_struct *target,
320 		     const struct user_regset *regset,
321 		     unsigned int pos, unsigned int count,
322 		     const void *kbuf, const void __user *ubuf)
323 {
324 	struct pt_regs *regs = task_pt_regs(target);
325 	u32 uregs[ELF_NGREG];
326 	unsigned start, num_regs, i;
327 	int err;
328 
329 	start = pos / sizeof(u32);
330 	num_regs = count / sizeof(u32);
331 
332 	if (start + num_regs > ELF_NGREG)
333 		return -EIO;
334 
335 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
336 				 sizeof(uregs));
337 	if (err)
338 		return err;
339 
340 	for (i = start; i < num_regs; i++) {
341 		/*
342 		 * Cast all values to signed here so that if this is a 64-bit
343 		 * kernel, the supplied 32-bit values will be sign extended.
344 		 */
345 		switch (i) {
346 		case MIPS32_EF_R1 ... MIPS32_EF_R25:
347 			/* k0/k1 are ignored. */
348 		case MIPS32_EF_R28 ... MIPS32_EF_R31:
349 			regs->regs[i - MIPS32_EF_R0] = (s32)uregs[i];
350 			break;
351 		case MIPS32_EF_LO:
352 			regs->lo = (s32)uregs[i];
353 			break;
354 		case MIPS32_EF_HI:
355 			regs->hi = (s32)uregs[i];
356 			break;
357 		case MIPS32_EF_CP0_EPC:
358 			regs->cp0_epc = (s32)uregs[i];
359 			break;
360 		}
361 	}
362 
363 	return 0;
364 }
365 
366 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
367 
368 #ifdef CONFIG_64BIT
369 
370 static int gpr64_get(struct task_struct *target,
371 		     const struct user_regset *regset,
372 		     unsigned int pos, unsigned int count,
373 		     void *kbuf, void __user *ubuf)
374 {
375 	struct pt_regs *regs = task_pt_regs(target);
376 	u64 uregs[ELF_NGREG] = {};
377 	unsigned i;
378 
379 	for (i = MIPS64_EF_R1; i <= MIPS64_EF_R31; i++) {
380 		/* k0/k1 are copied as zero. */
381 		if (i == MIPS64_EF_R26 || i == MIPS64_EF_R27)
382 			continue;
383 
384 		uregs[i] = regs->regs[i - MIPS64_EF_R0];
385 	}
386 
387 	uregs[MIPS64_EF_LO] = regs->lo;
388 	uregs[MIPS64_EF_HI] = regs->hi;
389 	uregs[MIPS64_EF_CP0_EPC] = regs->cp0_epc;
390 	uregs[MIPS64_EF_CP0_BADVADDR] = regs->cp0_badvaddr;
391 	uregs[MIPS64_EF_CP0_STATUS] = regs->cp0_status;
392 	uregs[MIPS64_EF_CP0_CAUSE] = regs->cp0_cause;
393 
394 	return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0,
395 				   sizeof(uregs));
396 }
397 
398 static int gpr64_set(struct task_struct *target,
399 		     const struct user_regset *regset,
400 		     unsigned int pos, unsigned int count,
401 		     const void *kbuf, const void __user *ubuf)
402 {
403 	struct pt_regs *regs = task_pt_regs(target);
404 	u64 uregs[ELF_NGREG];
405 	unsigned start, num_regs, i;
406 	int err;
407 
408 	start = pos / sizeof(u64);
409 	num_regs = count / sizeof(u64);
410 
411 	if (start + num_regs > ELF_NGREG)
412 		return -EIO;
413 
414 	err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, uregs, 0,
415 				 sizeof(uregs));
416 	if (err)
417 		return err;
418 
419 	for (i = start; i < num_regs; i++) {
420 		switch (i) {
421 		case MIPS64_EF_R1 ... MIPS64_EF_R25:
422 			/* k0/k1 are ignored. */
423 		case MIPS64_EF_R28 ... MIPS64_EF_R31:
424 			regs->regs[i - MIPS64_EF_R0] = uregs[i];
425 			break;
426 		case MIPS64_EF_LO:
427 			regs->lo = uregs[i];
428 			break;
429 		case MIPS64_EF_HI:
430 			regs->hi = uregs[i];
431 			break;
432 		case MIPS64_EF_CP0_EPC:
433 			regs->cp0_epc = uregs[i];
434 			break;
435 		}
436 	}
437 
438 	return 0;
439 }
440 
441 #endif /* CONFIG_64BIT */
442 
443 static int fpr_get(struct task_struct *target,
444 		   const struct user_regset *regset,
445 		   unsigned int pos, unsigned int count,
446 		   void *kbuf, void __user *ubuf)
447 {
448 	unsigned i;
449 	int err;
450 	u64 fpr_val;
451 
452 	/* XXX fcr31  */
453 
454 	if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
455 		return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
456 					   &target->thread.fpu,
457 					   0, sizeof(elf_fpregset_t));
458 
459 	for (i = 0; i < NUM_FPU_REGS; i++) {
460 		fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
461 		err = user_regset_copyout(&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 	}
467 
468 	return 0;
469 }
470 
471 static int fpr_set(struct task_struct *target,
472 		   const struct user_regset *regset,
473 		   unsigned int pos, unsigned int count,
474 		   const void *kbuf, const void __user *ubuf)
475 {
476 	unsigned i;
477 	int err;
478 	u64 fpr_val;
479 
480 	/* XXX fcr31  */
481 
482 	init_fp_ctx(target);
483 
484 	if (sizeof(target->thread.fpu.fpr[i]) == sizeof(elf_fpreg_t))
485 		return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
486 					  &target->thread.fpu,
487 					  0, sizeof(elf_fpregset_t));
488 
489 	for (i = 0; i < NUM_FPU_REGS; i++) {
490 		err = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
491 					 &fpr_val, i * sizeof(elf_fpreg_t),
492 					 (i + 1) * sizeof(elf_fpreg_t));
493 		if (err)
494 			return err;
495 		set_fpr64(&target->thread.fpu.fpr[i], 0, fpr_val);
496 	}
497 
498 	return 0;
499 }
500 
501 enum mips_regset {
502 	REGSET_GPR,
503 	REGSET_FPR,
504 };
505 
506 struct pt_regs_offset {
507 	const char *name;
508 	int offset;
509 };
510 
511 #define REG_OFFSET_NAME(reg, r) {					\
512 	.name = #reg,							\
513 	.offset = offsetof(struct pt_regs, r)				\
514 }
515 
516 #define REG_OFFSET_END {						\
517 	.name = NULL,							\
518 	.offset = 0							\
519 }
520 
521 static const struct pt_regs_offset regoffset_table[] = {
522 	REG_OFFSET_NAME(r0, regs[0]),
523 	REG_OFFSET_NAME(r1, regs[1]),
524 	REG_OFFSET_NAME(r2, regs[2]),
525 	REG_OFFSET_NAME(r3, regs[3]),
526 	REG_OFFSET_NAME(r4, regs[4]),
527 	REG_OFFSET_NAME(r5, regs[5]),
528 	REG_OFFSET_NAME(r6, regs[6]),
529 	REG_OFFSET_NAME(r7, regs[7]),
530 	REG_OFFSET_NAME(r8, regs[8]),
531 	REG_OFFSET_NAME(r9, regs[9]),
532 	REG_OFFSET_NAME(r10, regs[10]),
533 	REG_OFFSET_NAME(r11, regs[11]),
534 	REG_OFFSET_NAME(r12, regs[12]),
535 	REG_OFFSET_NAME(r13, regs[13]),
536 	REG_OFFSET_NAME(r14, regs[14]),
537 	REG_OFFSET_NAME(r15, regs[15]),
538 	REG_OFFSET_NAME(r16, regs[16]),
539 	REG_OFFSET_NAME(r17, regs[17]),
540 	REG_OFFSET_NAME(r18, regs[18]),
541 	REG_OFFSET_NAME(r19, regs[19]),
542 	REG_OFFSET_NAME(r20, regs[20]),
543 	REG_OFFSET_NAME(r21, regs[21]),
544 	REG_OFFSET_NAME(r22, regs[22]),
545 	REG_OFFSET_NAME(r23, regs[23]),
546 	REG_OFFSET_NAME(r24, regs[24]),
547 	REG_OFFSET_NAME(r25, regs[25]),
548 	REG_OFFSET_NAME(r26, regs[26]),
549 	REG_OFFSET_NAME(r27, regs[27]),
550 	REG_OFFSET_NAME(r28, regs[28]),
551 	REG_OFFSET_NAME(r29, regs[29]),
552 	REG_OFFSET_NAME(r30, regs[30]),
553 	REG_OFFSET_NAME(r31, regs[31]),
554 	REG_OFFSET_NAME(c0_status, cp0_status),
555 	REG_OFFSET_NAME(hi, hi),
556 	REG_OFFSET_NAME(lo, lo),
557 #ifdef CONFIG_CPU_HAS_SMARTMIPS
558 	REG_OFFSET_NAME(acx, acx),
559 #endif
560 	REG_OFFSET_NAME(c0_badvaddr, cp0_badvaddr),
561 	REG_OFFSET_NAME(c0_cause, cp0_cause),
562 	REG_OFFSET_NAME(c0_epc, cp0_epc),
563 #ifdef CONFIG_CPU_CAVIUM_OCTEON
564 	REG_OFFSET_NAME(mpl0, mpl[0]),
565 	REG_OFFSET_NAME(mpl1, mpl[1]),
566 	REG_OFFSET_NAME(mpl2, mpl[2]),
567 	REG_OFFSET_NAME(mtp0, mtp[0]),
568 	REG_OFFSET_NAME(mtp1, mtp[1]),
569 	REG_OFFSET_NAME(mtp2, mtp[2]),
570 #endif
571 	REG_OFFSET_END,
572 };
573 
574 /**
575  * regs_query_register_offset() - query register offset from its name
576  * @name:       the name of a register
577  *
578  * regs_query_register_offset() returns the offset of a register in struct
579  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
580  */
581 int regs_query_register_offset(const char *name)
582 {
583         const struct pt_regs_offset *roff;
584         for (roff = regoffset_table; roff->name != NULL; roff++)
585                 if (!strcmp(roff->name, name))
586                         return roff->offset;
587         return -EINVAL;
588 }
589 
590 #if defined(CONFIG_32BIT) || defined(CONFIG_MIPS32_O32)
591 
592 static const struct user_regset mips_regsets[] = {
593 	[REGSET_GPR] = {
594 		.core_note_type	= NT_PRSTATUS,
595 		.n		= ELF_NGREG,
596 		.size		= sizeof(unsigned int),
597 		.align		= sizeof(unsigned int),
598 		.get		= gpr32_get,
599 		.set		= gpr32_set,
600 	},
601 	[REGSET_FPR] = {
602 		.core_note_type	= NT_PRFPREG,
603 		.n		= ELF_NFPREG,
604 		.size		= sizeof(elf_fpreg_t),
605 		.align		= sizeof(elf_fpreg_t),
606 		.get		= fpr_get,
607 		.set		= fpr_set,
608 	},
609 };
610 
611 static const struct user_regset_view user_mips_view = {
612 	.name		= "mips",
613 	.e_machine	= ELF_ARCH,
614 	.ei_osabi	= ELF_OSABI,
615 	.regsets	= mips_regsets,
616 	.n		= ARRAY_SIZE(mips_regsets),
617 };
618 
619 #endif /* CONFIG_32BIT || CONFIG_MIPS32_O32 */
620 
621 #ifdef CONFIG_64BIT
622 
623 static const struct user_regset mips64_regsets[] = {
624 	[REGSET_GPR] = {
625 		.core_note_type	= NT_PRSTATUS,
626 		.n		= ELF_NGREG,
627 		.size		= sizeof(unsigned long),
628 		.align		= sizeof(unsigned long),
629 		.get		= gpr64_get,
630 		.set		= gpr64_set,
631 	},
632 	[REGSET_FPR] = {
633 		.core_note_type	= NT_PRFPREG,
634 		.n		= ELF_NFPREG,
635 		.size		= sizeof(elf_fpreg_t),
636 		.align		= sizeof(elf_fpreg_t),
637 		.get		= fpr_get,
638 		.set		= fpr_set,
639 	},
640 };
641 
642 static const struct user_regset_view user_mips64_view = {
643 	.name		= "mips64",
644 	.e_machine	= ELF_ARCH,
645 	.ei_osabi	= ELF_OSABI,
646 	.regsets	= mips64_regsets,
647 	.n		= ARRAY_SIZE(mips64_regsets),
648 };
649 
650 #endif /* CONFIG_64BIT */
651 
652 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
653 {
654 #ifdef CONFIG_32BIT
655 	return &user_mips_view;
656 #else
657 #ifdef CONFIG_MIPS32_O32
658 	if (test_tsk_thread_flag(task, TIF_32BIT_REGS))
659 		return &user_mips_view;
660 #endif
661 	return &user_mips64_view;
662 #endif
663 }
664 
665 long arch_ptrace(struct task_struct *child, long request,
666 		 unsigned long addr, unsigned long data)
667 {
668 	int ret;
669 	void __user *addrp = (void __user *) addr;
670 	void __user *datavp = (void __user *) data;
671 	unsigned long __user *datalp = (void __user *) data;
672 
673 	switch (request) {
674 	/* when I and D space are separate, these will need to be fixed. */
675 	case PTRACE_PEEKTEXT: /* read word at location addr. */
676 	case PTRACE_PEEKDATA:
677 		ret = generic_ptrace_peekdata(child, addr, data);
678 		break;
679 
680 	/* Read the word at location addr in the USER area. */
681 	case PTRACE_PEEKUSR: {
682 		struct pt_regs *regs;
683 		union fpureg *fregs;
684 		unsigned long tmp = 0;
685 
686 		regs = task_pt_regs(child);
687 		ret = 0;  /* Default return value. */
688 
689 		switch (addr) {
690 		case 0 ... 31:
691 			tmp = regs->regs[addr];
692 			break;
693 		case FPR_BASE ... FPR_BASE + 31:
694 			if (!tsk_used_math(child)) {
695 				/* FP not yet used */
696 				tmp = -1;
697 				break;
698 			}
699 			fregs = get_fpu_regs(child);
700 
701 #ifdef CONFIG_32BIT
702 			if (test_thread_flag(TIF_32BIT_FPREGS)) {
703 				/*
704 				 * The odd registers are actually the high
705 				 * order bits of the values stored in the even
706 				 * registers - unless we're using r2k_switch.S.
707 				 */
708 				tmp = get_fpr32(&fregs[(addr & ~1) - FPR_BASE],
709 						addr & 1);
710 				break;
711 			}
712 #endif
713 			tmp = get_fpr32(&fregs[addr - FPR_BASE], 0);
714 			break;
715 		case PC:
716 			tmp = regs->cp0_epc;
717 			break;
718 		case CAUSE:
719 			tmp = regs->cp0_cause;
720 			break;
721 		case BADVADDR:
722 			tmp = regs->cp0_badvaddr;
723 			break;
724 		case MMHI:
725 			tmp = regs->hi;
726 			break;
727 		case MMLO:
728 			tmp = regs->lo;
729 			break;
730 #ifdef CONFIG_CPU_HAS_SMARTMIPS
731 		case ACX:
732 			tmp = regs->acx;
733 			break;
734 #endif
735 		case FPC_CSR:
736 			tmp = child->thread.fpu.fcr31;
737 			break;
738 		case FPC_EIR:
739 			/* implementation / version register */
740 			tmp = boot_cpu_data.fpu_id;
741 			break;
742 		case DSP_BASE ... DSP_BASE + 5: {
743 			dspreg_t *dregs;
744 
745 			if (!cpu_has_dsp) {
746 				tmp = 0;
747 				ret = -EIO;
748 				goto out;
749 			}
750 			dregs = __get_dsp_regs(child);
751 			tmp = (unsigned long) (dregs[addr - DSP_BASE]);
752 			break;
753 		}
754 		case DSP_CONTROL:
755 			if (!cpu_has_dsp) {
756 				tmp = 0;
757 				ret = -EIO;
758 				goto out;
759 			}
760 			tmp = child->thread.dsp.dspcontrol;
761 			break;
762 		default:
763 			tmp = 0;
764 			ret = -EIO;
765 			goto out;
766 		}
767 		ret = put_user(tmp, datalp);
768 		break;
769 	}
770 
771 	/* when I and D space are separate, this will have to be fixed. */
772 	case PTRACE_POKETEXT: /* write the word at location addr. */
773 	case PTRACE_POKEDATA:
774 		ret = generic_ptrace_pokedata(child, addr, data);
775 		break;
776 
777 	case PTRACE_POKEUSR: {
778 		struct pt_regs *regs;
779 		ret = 0;
780 		regs = task_pt_regs(child);
781 
782 		switch (addr) {
783 		case 0 ... 31:
784 			regs->regs[addr] = data;
785 			break;
786 		case FPR_BASE ... FPR_BASE + 31: {
787 			union fpureg *fregs = get_fpu_regs(child);
788 
789 			init_fp_ctx(child);
790 #ifdef CONFIG_32BIT
791 			if (test_thread_flag(TIF_32BIT_FPREGS)) {
792 				/*
793 				 * The odd registers are actually the high
794 				 * order bits of the values stored in the even
795 				 * registers - unless we're using r2k_switch.S.
796 				 */
797 				set_fpr32(&fregs[(addr & ~1) - FPR_BASE],
798 					  addr & 1, data);
799 				break;
800 			}
801 #endif
802 			set_fpr64(&fregs[addr - FPR_BASE], 0, data);
803 			break;
804 		}
805 		case PC:
806 			regs->cp0_epc = data;
807 			break;
808 		case MMHI:
809 			regs->hi = data;
810 			break;
811 		case MMLO:
812 			regs->lo = data;
813 			break;
814 #ifdef CONFIG_CPU_HAS_SMARTMIPS
815 		case ACX:
816 			regs->acx = data;
817 			break;
818 #endif
819 		case FPC_CSR:
820 			ptrace_setfcr31(child, data);
821 			break;
822 		case DSP_BASE ... DSP_BASE + 5: {
823 			dspreg_t *dregs;
824 
825 			if (!cpu_has_dsp) {
826 				ret = -EIO;
827 				break;
828 			}
829 
830 			dregs = __get_dsp_regs(child);
831 			dregs[addr - DSP_BASE] = data;
832 			break;
833 		}
834 		case DSP_CONTROL:
835 			if (!cpu_has_dsp) {
836 				ret = -EIO;
837 				break;
838 			}
839 			child->thread.dsp.dspcontrol = data;
840 			break;
841 		default:
842 			/* The rest are not allowed. */
843 			ret = -EIO;
844 			break;
845 		}
846 		break;
847 		}
848 
849 	case PTRACE_GETREGS:
850 		ret = ptrace_getregs(child, datavp);
851 		break;
852 
853 	case PTRACE_SETREGS:
854 		ret = ptrace_setregs(child, datavp);
855 		break;
856 
857 	case PTRACE_GETFPREGS:
858 		ret = ptrace_getfpregs(child, datavp);
859 		break;
860 
861 	case PTRACE_SETFPREGS:
862 		ret = ptrace_setfpregs(child, datavp);
863 		break;
864 
865 	case PTRACE_GET_THREAD_AREA:
866 		ret = put_user(task_thread_info(child)->tp_value, datalp);
867 		break;
868 
869 	case PTRACE_GET_WATCH_REGS:
870 		ret = ptrace_get_watch_regs(child, addrp);
871 		break;
872 
873 	case PTRACE_SET_WATCH_REGS:
874 		ret = ptrace_set_watch_regs(child, addrp);
875 		break;
876 
877 	default:
878 		ret = ptrace_request(child, request, addr, data);
879 		break;
880 	}
881  out:
882 	return ret;
883 }
884 
885 /*
886  * Notification of system call entry/exit
887  * - triggered by current->work.syscall_trace
888  */
889 asmlinkage long syscall_trace_enter(struct pt_regs *regs, long syscall)
890 {
891 	long ret = 0;
892 	user_exit();
893 
894 	current_thread_info()->syscall = syscall;
895 
896 	if (secure_computing() == -1)
897 		return -1;
898 
899 	if (test_thread_flag(TIF_SYSCALL_TRACE) &&
900 	    tracehook_report_syscall_entry(regs))
901 		ret = -1;
902 
903 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
904 		trace_sys_enter(regs, regs->regs[2]);
905 
906 	audit_syscall_entry(syscall, regs->regs[4], regs->regs[5],
907 			    regs->regs[6], regs->regs[7]);
908 	return syscall;
909 }
910 
911 /*
912  * Notification of system call entry/exit
913  * - triggered by current->work.syscall_trace
914  */
915 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
916 {
917         /*
918 	 * We may come here right after calling schedule_user()
919 	 * or do_notify_resume(), in which case we can be in RCU
920 	 * user mode.
921 	 */
922 	user_exit();
923 
924 	audit_syscall_exit(regs);
925 
926 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
927 		trace_sys_exit(regs, regs->regs[2]);
928 
929 	if (test_thread_flag(TIF_SYSCALL_TRACE))
930 		tracehook_report_syscall_exit(regs, 0);
931 
932 	user_enter();
933 }
934