xref: /openbmc/linux/arch/sparc/kernel/ptrace_64.c (revision 8730046c)
1 /* ptrace.c: Sparc process tracing support.
2  *
3  * Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
4  * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
5  *
6  * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
7  * and David Mosberger.
8  *
9  * Added Linux support -miguel (weird, eh?, the original code was meant
10  * to emulate SunOS).
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/mm.h>
16 #include <linux/errno.h>
17 #include <linux/export.h>
18 #include <linux/ptrace.h>
19 #include <linux/user.h>
20 #include <linux/smp.h>
21 #include <linux/security.h>
22 #include <linux/seccomp.h>
23 #include <linux/audit.h>
24 #include <linux/signal.h>
25 #include <linux/regset.h>
26 #include <linux/tracehook.h>
27 #include <trace/syscall.h>
28 #include <linux/compat.h>
29 #include <linux/elf.h>
30 #include <linux/context_tracking.h>
31 
32 #include <asm/asi.h>
33 #include <asm/pgtable.h>
34 #include <linux/uaccess.h>
35 #include <asm/psrcompat.h>
36 #include <asm/visasm.h>
37 #include <asm/spitfire.h>
38 #include <asm/page.h>
39 #include <asm/cpudata.h>
40 #include <asm/cacheflush.h>
41 
42 #define CREATE_TRACE_POINTS
43 #include <trace/events/syscalls.h>
44 
45 #include "entry.h"
46 
47 /* #define ALLOW_INIT_TRACING */
48 
49 struct pt_regs_offset {
50 	const char *name;
51 	int offset;
52 };
53 
54 #define REG_OFFSET_NAME(n, r) \
55 	{.name = n, .offset = (PT_V9_##r)}
56 #define REG_OFFSET_END {.name = NULL, .offset = 0}
57 
58 static const struct pt_regs_offset regoffset_table[] = {
59 	REG_OFFSET_NAME("g0", G0),
60 	REG_OFFSET_NAME("g1", G1),
61 	REG_OFFSET_NAME("g2", G2),
62 	REG_OFFSET_NAME("g3", G3),
63 	REG_OFFSET_NAME("g4", G4),
64 	REG_OFFSET_NAME("g5", G5),
65 	REG_OFFSET_NAME("g6", G6),
66 	REG_OFFSET_NAME("g7", G7),
67 
68 	REG_OFFSET_NAME("i0", I0),
69 	REG_OFFSET_NAME("i1", I1),
70 	REG_OFFSET_NAME("i2", I2),
71 	REG_OFFSET_NAME("i3", I3),
72 	REG_OFFSET_NAME("i4", I4),
73 	REG_OFFSET_NAME("i5", I5),
74 	REG_OFFSET_NAME("i6", I6),
75 	REG_OFFSET_NAME("i7", I7),
76 
77 	REG_OFFSET_NAME("tstate", TSTATE),
78 	REG_OFFSET_NAME("pc", TPC),
79 	REG_OFFSET_NAME("npc", TNPC),
80 	REG_OFFSET_NAME("y", Y),
81 	REG_OFFSET_NAME("lr", I7),
82 
83 	REG_OFFSET_END,
84 };
85 
86 /*
87  * Called by kernel/ptrace.c when detaching..
88  *
89  * Make sure single step bits etc are not set.
90  */
91 void ptrace_disable(struct task_struct *child)
92 {
93 	/* nothing to do */
94 }
95 
96 /* To get the necessary page struct, access_process_vm() first calls
97  * get_user_pages().  This has done a flush_dcache_page() on the
98  * accessed page.  Then our caller (copy_{to,from}_user_page()) did
99  * to memcpy to read/write the data from that page.
100  *
101  * Now, the only thing we have to do is:
102  * 1) flush the D-cache if it's possible than an illegal alias
103  *    has been created
104  * 2) flush the I-cache if this is pre-cheetah and we did a write
105  */
106 void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
107 			 unsigned long uaddr, void *kaddr,
108 			 unsigned long len, int write)
109 {
110 	BUG_ON(len > PAGE_SIZE);
111 
112 	if (tlb_type == hypervisor)
113 		return;
114 
115 	preempt_disable();
116 
117 #ifdef DCACHE_ALIASING_POSSIBLE
118 	/* If bit 13 of the kernel address we used to access the
119 	 * user page is the same as the virtual address that page
120 	 * is mapped to in the user's address space, we can skip the
121 	 * D-cache flush.
122 	 */
123 	if ((uaddr ^ (unsigned long) kaddr) & (1UL << 13)) {
124 		unsigned long start = __pa(kaddr);
125 		unsigned long end = start + len;
126 		unsigned long dcache_line_size;
127 
128 		dcache_line_size = local_cpu_data().dcache_line_size;
129 
130 		if (tlb_type == spitfire) {
131 			for (; start < end; start += dcache_line_size)
132 				spitfire_put_dcache_tag(start & 0x3fe0, 0x0);
133 		} else {
134 			start &= ~(dcache_line_size - 1);
135 			for (; start < end; start += dcache_line_size)
136 				__asm__ __volatile__(
137 					"stxa %%g0, [%0] %1\n\t"
138 					"membar #Sync"
139 					: /* no outputs */
140 					: "r" (start),
141 					"i" (ASI_DCACHE_INVALIDATE));
142 		}
143 	}
144 #endif
145 	if (write && tlb_type == spitfire) {
146 		unsigned long start = (unsigned long) kaddr;
147 		unsigned long end = start + len;
148 		unsigned long icache_line_size;
149 
150 		icache_line_size = local_cpu_data().icache_line_size;
151 
152 		for (; start < end; start += icache_line_size)
153 			flushi(start);
154 	}
155 
156 	preempt_enable();
157 }
158 EXPORT_SYMBOL_GPL(flush_ptrace_access);
159 
160 static int get_from_target(struct task_struct *target, unsigned long uaddr,
161 			   void *kbuf, int len)
162 {
163 	if (target == current) {
164 		if (copy_from_user(kbuf, (void __user *) uaddr, len))
165 			return -EFAULT;
166 	} else {
167 		int len2 = access_process_vm(target, uaddr, kbuf, len,
168 				FOLL_FORCE);
169 		if (len2 != len)
170 			return -EFAULT;
171 	}
172 	return 0;
173 }
174 
175 static int set_to_target(struct task_struct *target, unsigned long uaddr,
176 			 void *kbuf, int len)
177 {
178 	if (target == current) {
179 		if (copy_to_user((void __user *) uaddr, kbuf, len))
180 			return -EFAULT;
181 	} else {
182 		int len2 = access_process_vm(target, uaddr, kbuf, len,
183 				FOLL_FORCE | FOLL_WRITE);
184 		if (len2 != len)
185 			return -EFAULT;
186 	}
187 	return 0;
188 }
189 
190 static int regwindow64_get(struct task_struct *target,
191 			   const struct pt_regs *regs,
192 			   struct reg_window *wbuf)
193 {
194 	unsigned long rw_addr = regs->u_regs[UREG_I6];
195 
196 	if (!test_thread_64bit_stack(rw_addr)) {
197 		struct reg_window32 win32;
198 		int i;
199 
200 		if (get_from_target(target, rw_addr, &win32, sizeof(win32)))
201 			return -EFAULT;
202 		for (i = 0; i < 8; i++)
203 			wbuf->locals[i] = win32.locals[i];
204 		for (i = 0; i < 8; i++)
205 			wbuf->ins[i] = win32.ins[i];
206 	} else {
207 		rw_addr += STACK_BIAS;
208 		if (get_from_target(target, rw_addr, wbuf, sizeof(*wbuf)))
209 			return -EFAULT;
210 	}
211 
212 	return 0;
213 }
214 
215 static int regwindow64_set(struct task_struct *target,
216 			   const struct pt_regs *regs,
217 			   struct reg_window *wbuf)
218 {
219 	unsigned long rw_addr = regs->u_regs[UREG_I6];
220 
221 	if (!test_thread_64bit_stack(rw_addr)) {
222 		struct reg_window32 win32;
223 		int i;
224 
225 		for (i = 0; i < 8; i++)
226 			win32.locals[i] = wbuf->locals[i];
227 		for (i = 0; i < 8; i++)
228 			win32.ins[i] = wbuf->ins[i];
229 
230 		if (set_to_target(target, rw_addr, &win32, sizeof(win32)))
231 			return -EFAULT;
232 	} else {
233 		rw_addr += STACK_BIAS;
234 		if (set_to_target(target, rw_addr, wbuf, sizeof(*wbuf)))
235 			return -EFAULT;
236 	}
237 
238 	return 0;
239 }
240 
241 enum sparc_regset {
242 	REGSET_GENERAL,
243 	REGSET_FP,
244 };
245 
246 static int genregs64_get(struct task_struct *target,
247 			 const struct user_regset *regset,
248 			 unsigned int pos, unsigned int count,
249 			 void *kbuf, void __user *ubuf)
250 {
251 	const struct pt_regs *regs = task_pt_regs(target);
252 	int ret;
253 
254 	if (target == current)
255 		flushw_user();
256 
257 	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
258 				  regs->u_regs,
259 				  0, 16 * sizeof(u64));
260 	if (!ret && count && pos < (32 * sizeof(u64))) {
261 		struct reg_window window;
262 
263 		if (regwindow64_get(target, regs, &window))
264 			return -EFAULT;
265 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
266 					  &window,
267 					  16 * sizeof(u64),
268 					  32 * sizeof(u64));
269 	}
270 
271 	if (!ret) {
272 		/* TSTATE, TPC, TNPC */
273 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
274 					  &regs->tstate,
275 					  32 * sizeof(u64),
276 					  35 * sizeof(u64));
277 	}
278 
279 	if (!ret) {
280 		unsigned long y = regs->y;
281 
282 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
283 					  &y,
284 					  35 * sizeof(u64),
285 					  36 * sizeof(u64));
286 	}
287 
288 	if (!ret) {
289 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
290 					       36 * sizeof(u64), -1);
291 
292 	}
293 	return ret;
294 }
295 
296 static int genregs64_set(struct task_struct *target,
297 			 const struct user_regset *regset,
298 			 unsigned int pos, unsigned int count,
299 			 const void *kbuf, const void __user *ubuf)
300 {
301 	struct pt_regs *regs = task_pt_regs(target);
302 	int ret;
303 
304 	if (target == current)
305 		flushw_user();
306 
307 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
308 				 regs->u_regs,
309 				 0, 16 * sizeof(u64));
310 	if (!ret && count && pos < (32 * sizeof(u64))) {
311 		struct reg_window window;
312 
313 		if (regwindow64_get(target, regs, &window))
314 			return -EFAULT;
315 
316 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
317 					 &window,
318 					 16 * sizeof(u64),
319 					 32 * sizeof(u64));
320 
321 		if (!ret &&
322 		    regwindow64_set(target, regs, &window))
323 			return -EFAULT;
324 	}
325 
326 	if (!ret && count > 0) {
327 		unsigned long tstate;
328 
329 		/* TSTATE */
330 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
331 					 &tstate,
332 					 32 * sizeof(u64),
333 					 33 * sizeof(u64));
334 		if (!ret) {
335 			/* Only the condition codes and the "in syscall"
336 			 * state can be modified in the %tstate register.
337 			 */
338 			tstate &= (TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
339 			regs->tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
340 			regs->tstate |= tstate;
341 		}
342 	}
343 
344 	if (!ret) {
345 		/* TPC, TNPC */
346 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
347 					 &regs->tpc,
348 					 33 * sizeof(u64),
349 					 35 * sizeof(u64));
350 	}
351 
352 	if (!ret) {
353 		unsigned long y;
354 
355 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
356 					 &y,
357 					 35 * sizeof(u64),
358 					 36 * sizeof(u64));
359 		if (!ret)
360 			regs->y = y;
361 	}
362 
363 	if (!ret)
364 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
365 						36 * sizeof(u64), -1);
366 
367 	return ret;
368 }
369 
370 static int fpregs64_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 	const unsigned long *fpregs = task_thread_info(target)->fpregs;
376 	unsigned long fprs, fsr, gsr;
377 	int ret;
378 
379 	if (target == current)
380 		save_and_clear_fpu();
381 
382 	fprs = task_thread_info(target)->fpsaved[0];
383 
384 	if (fprs & FPRS_DL)
385 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
386 					  fpregs,
387 					  0, 16 * sizeof(u64));
388 	else
389 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
390 					       0,
391 					       16 * sizeof(u64));
392 
393 	if (!ret) {
394 		if (fprs & FPRS_DU)
395 			ret = user_regset_copyout(&pos, &count,
396 						  &kbuf, &ubuf,
397 						  fpregs + 16,
398 						  16 * sizeof(u64),
399 						  32 * sizeof(u64));
400 		else
401 			ret = user_regset_copyout_zero(&pos, &count,
402 						       &kbuf, &ubuf,
403 						       16 * sizeof(u64),
404 						       32 * sizeof(u64));
405 	}
406 
407 	if (fprs & FPRS_FEF) {
408 		fsr = task_thread_info(target)->xfsr[0];
409 		gsr = task_thread_info(target)->gsr[0];
410 	} else {
411 		fsr = gsr = 0;
412 	}
413 
414 	if (!ret)
415 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
416 					  &fsr,
417 					  32 * sizeof(u64),
418 					  33 * sizeof(u64));
419 	if (!ret)
420 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
421 					  &gsr,
422 					  33 * sizeof(u64),
423 					  34 * sizeof(u64));
424 	if (!ret)
425 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
426 					  &fprs,
427 					  34 * sizeof(u64),
428 					  35 * sizeof(u64));
429 
430 	if (!ret)
431 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
432 					       35 * sizeof(u64), -1);
433 
434 	return ret;
435 }
436 
437 static int fpregs64_set(struct task_struct *target,
438 			const struct user_regset *regset,
439 			unsigned int pos, unsigned int count,
440 			const void *kbuf, const void __user *ubuf)
441 {
442 	unsigned long *fpregs = task_thread_info(target)->fpregs;
443 	unsigned long fprs;
444 	int ret;
445 
446 	if (target == current)
447 		save_and_clear_fpu();
448 
449 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
450 				 fpregs,
451 				 0, 32 * sizeof(u64));
452 	if (!ret)
453 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
454 					 task_thread_info(target)->xfsr,
455 					 32 * sizeof(u64),
456 					 33 * sizeof(u64));
457 	if (!ret)
458 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
459 					 task_thread_info(target)->gsr,
460 					 33 * sizeof(u64),
461 					 34 * sizeof(u64));
462 
463 	fprs = task_thread_info(target)->fpsaved[0];
464 	if (!ret && count > 0) {
465 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
466 					 &fprs,
467 					 34 * sizeof(u64),
468 					 35 * sizeof(u64));
469 	}
470 
471 	fprs |= (FPRS_FEF | FPRS_DL | FPRS_DU);
472 	task_thread_info(target)->fpsaved[0] = fprs;
473 
474 	if (!ret)
475 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
476 						35 * sizeof(u64), -1);
477 	return ret;
478 }
479 
480 static const struct user_regset sparc64_regsets[] = {
481 	/* Format is:
482 	 * 	G0 --> G7
483 	 *	O0 --> O7
484 	 *	L0 --> L7
485 	 *	I0 --> I7
486 	 *	TSTATE, TPC, TNPC, Y
487 	 */
488 	[REGSET_GENERAL] = {
489 		.core_note_type = NT_PRSTATUS,
490 		.n = 36,
491 		.size = sizeof(u64), .align = sizeof(u64),
492 		.get = genregs64_get, .set = genregs64_set
493 	},
494 	/* Format is:
495 	 *	F0 --> F63
496 	 *	FSR
497 	 *	GSR
498 	 *	FPRS
499 	 */
500 	[REGSET_FP] = {
501 		.core_note_type = NT_PRFPREG,
502 		.n = 35,
503 		.size = sizeof(u64), .align = sizeof(u64),
504 		.get = fpregs64_get, .set = fpregs64_set
505 	},
506 };
507 
508 static const struct user_regset_view user_sparc64_view = {
509 	.name = "sparc64", .e_machine = EM_SPARCV9,
510 	.regsets = sparc64_regsets, .n = ARRAY_SIZE(sparc64_regsets)
511 };
512 
513 #ifdef CONFIG_COMPAT
514 static int genregs32_get(struct task_struct *target,
515 			 const struct user_regset *regset,
516 			 unsigned int pos, unsigned int count,
517 			 void *kbuf, void __user *ubuf)
518 {
519 	const struct pt_regs *regs = task_pt_regs(target);
520 	compat_ulong_t __user *reg_window;
521 	compat_ulong_t *k = kbuf;
522 	compat_ulong_t __user *u = ubuf;
523 	compat_ulong_t reg;
524 
525 	if (target == current)
526 		flushw_user();
527 
528 	pos /= sizeof(reg);
529 	count /= sizeof(reg);
530 
531 	if (kbuf) {
532 		for (; count > 0 && pos < 16; count--)
533 			*k++ = regs->u_regs[pos++];
534 
535 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
536 		reg_window -= 16;
537 		if (target == current) {
538 			for (; count > 0 && pos < 32; count--) {
539 				if (get_user(*k++, &reg_window[pos++]))
540 					return -EFAULT;
541 			}
542 		} else {
543 			for (; count > 0 && pos < 32; count--) {
544 				if (access_process_vm(target,
545 						      (unsigned long)
546 						      &reg_window[pos],
547 						      k, sizeof(*k),
548 						      FOLL_FORCE)
549 				    != sizeof(*k))
550 					return -EFAULT;
551 				k++;
552 				pos++;
553 			}
554 		}
555 	} else {
556 		for (; count > 0 && pos < 16; count--) {
557 			if (put_user((compat_ulong_t) regs->u_regs[pos++], u++))
558 				return -EFAULT;
559 		}
560 
561 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
562 		reg_window -= 16;
563 		if (target == current) {
564 			for (; count > 0 && pos < 32; count--) {
565 				if (get_user(reg, &reg_window[pos++]) ||
566 				    put_user(reg, u++))
567 					return -EFAULT;
568 			}
569 		} else {
570 			for (; count > 0 && pos < 32; count--) {
571 				if (access_process_vm(target,
572 						      (unsigned long)
573 						      &reg_window[pos],
574 						      &reg, sizeof(reg),
575 						      FOLL_FORCE)
576 				    != sizeof(reg))
577 					return -EFAULT;
578 				if (access_process_vm(target,
579 						      (unsigned long) u,
580 						      &reg, sizeof(reg),
581 						      FOLL_FORCE | FOLL_WRITE)
582 				    != sizeof(reg))
583 					return -EFAULT;
584 				pos++;
585 				u++;
586 			}
587 		}
588 	}
589 	while (count > 0) {
590 		switch (pos) {
591 		case 32: /* PSR */
592 			reg = tstate_to_psr(regs->tstate);
593 			break;
594 		case 33: /* PC */
595 			reg = regs->tpc;
596 			break;
597 		case 34: /* NPC */
598 			reg = regs->tnpc;
599 			break;
600 		case 35: /* Y */
601 			reg = regs->y;
602 			break;
603 		case 36: /* WIM */
604 		case 37: /* TBR */
605 			reg = 0;
606 			break;
607 		default:
608 			goto finish;
609 		}
610 
611 		if (kbuf)
612 			*k++ = reg;
613 		else if (put_user(reg, u++))
614 			return -EFAULT;
615 		pos++;
616 		count--;
617 	}
618 finish:
619 	pos *= sizeof(reg);
620 	count *= sizeof(reg);
621 
622 	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
623 					38 * sizeof(reg), -1);
624 }
625 
626 static int genregs32_set(struct task_struct *target,
627 			 const struct user_regset *regset,
628 			 unsigned int pos, unsigned int count,
629 			 const void *kbuf, const void __user *ubuf)
630 {
631 	struct pt_regs *regs = task_pt_regs(target);
632 	compat_ulong_t __user *reg_window;
633 	const compat_ulong_t *k = kbuf;
634 	const compat_ulong_t __user *u = ubuf;
635 	compat_ulong_t reg;
636 
637 	if (target == current)
638 		flushw_user();
639 
640 	pos /= sizeof(reg);
641 	count /= sizeof(reg);
642 
643 	if (kbuf) {
644 		for (; count > 0 && pos < 16; count--)
645 			regs->u_regs[pos++] = *k++;
646 
647 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
648 		reg_window -= 16;
649 		if (target == current) {
650 			for (; count > 0 && pos < 32; count--) {
651 				if (put_user(*k++, &reg_window[pos++]))
652 					return -EFAULT;
653 			}
654 		} else {
655 			for (; count > 0 && pos < 32; count--) {
656 				if (access_process_vm(target,
657 						      (unsigned long)
658 						      &reg_window[pos],
659 						      (void *) k,
660 						      sizeof(*k),
661 						      FOLL_FORCE | FOLL_WRITE)
662 				    != sizeof(*k))
663 					return -EFAULT;
664 				k++;
665 				pos++;
666 			}
667 		}
668 	} else {
669 		for (; count > 0 && pos < 16; count--) {
670 			if (get_user(reg, u++))
671 				return -EFAULT;
672 			regs->u_regs[pos++] = reg;
673 		}
674 
675 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
676 		reg_window -= 16;
677 		if (target == current) {
678 			for (; count > 0 && pos < 32; count--) {
679 				if (get_user(reg, u++) ||
680 				    put_user(reg, &reg_window[pos++]))
681 					return -EFAULT;
682 			}
683 		} else {
684 			for (; count > 0 && pos < 32; count--) {
685 				if (access_process_vm(target,
686 						      (unsigned long)
687 						      u,
688 						      &reg, sizeof(reg),
689 						      FOLL_FORCE)
690 				    != sizeof(reg))
691 					return -EFAULT;
692 				if (access_process_vm(target,
693 						      (unsigned long)
694 						      &reg_window[pos],
695 						      &reg, sizeof(reg),
696 						      FOLL_FORCE | FOLL_WRITE)
697 				    != sizeof(reg))
698 					return -EFAULT;
699 				pos++;
700 				u++;
701 			}
702 		}
703 	}
704 	while (count > 0) {
705 		unsigned long tstate;
706 
707 		if (kbuf)
708 			reg = *k++;
709 		else if (get_user(reg, u++))
710 			return -EFAULT;
711 
712 		switch (pos) {
713 		case 32: /* PSR */
714 			tstate = regs->tstate;
715 			tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
716 			tstate |= psr_to_tstate_icc(reg);
717 			if (reg & PSR_SYSCALL)
718 				tstate |= TSTATE_SYSCALL;
719 			regs->tstate = tstate;
720 			break;
721 		case 33: /* PC */
722 			regs->tpc = reg;
723 			break;
724 		case 34: /* NPC */
725 			regs->tnpc = reg;
726 			break;
727 		case 35: /* Y */
728 			regs->y = reg;
729 			break;
730 		case 36: /* WIM */
731 		case 37: /* TBR */
732 			break;
733 		default:
734 			goto finish;
735 		}
736 
737 		pos++;
738 		count--;
739 	}
740 finish:
741 	pos *= sizeof(reg);
742 	count *= sizeof(reg);
743 
744 	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
745 					 38 * sizeof(reg), -1);
746 }
747 
748 static int fpregs32_get(struct task_struct *target,
749 			const struct user_regset *regset,
750 			unsigned int pos, unsigned int count,
751 			void *kbuf, void __user *ubuf)
752 {
753 	const unsigned long *fpregs = task_thread_info(target)->fpregs;
754 	compat_ulong_t enabled;
755 	unsigned long fprs;
756 	compat_ulong_t fsr;
757 	int ret = 0;
758 
759 	if (target == current)
760 		save_and_clear_fpu();
761 
762 	fprs = task_thread_info(target)->fpsaved[0];
763 	if (fprs & FPRS_FEF) {
764 		fsr = task_thread_info(target)->xfsr[0];
765 		enabled = 1;
766 	} else {
767 		fsr = 0;
768 		enabled = 0;
769 	}
770 
771 	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
772 				  fpregs,
773 				  0, 32 * sizeof(u32));
774 
775 	if (!ret)
776 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
777 					       32 * sizeof(u32),
778 					       33 * sizeof(u32));
779 	if (!ret)
780 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
781 					  &fsr,
782 					  33 * sizeof(u32),
783 					  34 * sizeof(u32));
784 
785 	if (!ret) {
786 		compat_ulong_t val;
787 
788 		val = (enabled << 8) | (8 << 16);
789 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
790 					  &val,
791 					  34 * sizeof(u32),
792 					  35 * sizeof(u32));
793 	}
794 
795 	if (!ret)
796 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
797 					       35 * sizeof(u32), -1);
798 
799 	return ret;
800 }
801 
802 static int fpregs32_set(struct task_struct *target,
803 			const struct user_regset *regset,
804 			unsigned int pos, unsigned int count,
805 			const void *kbuf, const void __user *ubuf)
806 {
807 	unsigned long *fpregs = task_thread_info(target)->fpregs;
808 	unsigned long fprs;
809 	int ret;
810 
811 	if (target == current)
812 		save_and_clear_fpu();
813 
814 	fprs = task_thread_info(target)->fpsaved[0];
815 
816 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
817 				 fpregs,
818 				 0, 32 * sizeof(u32));
819 	if (!ret)
820 		user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
821 					  32 * sizeof(u32),
822 					  33 * sizeof(u32));
823 	if (!ret && count > 0) {
824 		compat_ulong_t fsr;
825 		unsigned long val;
826 
827 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
828 					 &fsr,
829 					 33 * sizeof(u32),
830 					 34 * sizeof(u32));
831 		if (!ret) {
832 			val = task_thread_info(target)->xfsr[0];
833 			val &= 0xffffffff00000000UL;
834 			val |= fsr;
835 			task_thread_info(target)->xfsr[0] = val;
836 		}
837 	}
838 
839 	fprs |= (FPRS_FEF | FPRS_DL);
840 	task_thread_info(target)->fpsaved[0] = fprs;
841 
842 	if (!ret)
843 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
844 						34 * sizeof(u32), -1);
845 	return ret;
846 }
847 
848 static const struct user_regset sparc32_regsets[] = {
849 	/* Format is:
850 	 * 	G0 --> G7
851 	 *	O0 --> O7
852 	 *	L0 --> L7
853 	 *	I0 --> I7
854 	 *	PSR, PC, nPC, Y, WIM, TBR
855 	 */
856 	[REGSET_GENERAL] = {
857 		.core_note_type = NT_PRSTATUS,
858 		.n = 38,
859 		.size = sizeof(u32), .align = sizeof(u32),
860 		.get = genregs32_get, .set = genregs32_set
861 	},
862 	/* Format is:
863 	 *	F0 --> F31
864 	 *	empty 32-bit word
865 	 *	FSR (32--bit word)
866 	 *	FPU QUEUE COUNT (8-bit char)
867 	 *	FPU QUEUE ENTRYSIZE (8-bit char)
868 	 *	FPU ENABLED (8-bit char)
869 	 *	empty 8-bit char
870 	 *	FPU QUEUE (64 32-bit ints)
871 	 */
872 	[REGSET_FP] = {
873 		.core_note_type = NT_PRFPREG,
874 		.n = 99,
875 		.size = sizeof(u32), .align = sizeof(u32),
876 		.get = fpregs32_get, .set = fpregs32_set
877 	},
878 };
879 
880 static const struct user_regset_view user_sparc32_view = {
881 	.name = "sparc", .e_machine = EM_SPARC,
882 	.regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
883 };
884 #endif /* CONFIG_COMPAT */
885 
886 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
887 {
888 #ifdef CONFIG_COMPAT
889 	if (test_tsk_thread_flag(task, TIF_32BIT))
890 		return &user_sparc32_view;
891 #endif
892 	return &user_sparc64_view;
893 }
894 
895 #ifdef CONFIG_COMPAT
896 struct compat_fps {
897 	unsigned int regs[32];
898 	unsigned int fsr;
899 	unsigned int flags;
900 	unsigned int extra;
901 	unsigned int fpqd;
902 	struct compat_fq {
903 		unsigned int insnaddr;
904 		unsigned int insn;
905 	} fpq[16];
906 };
907 
908 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
909 			compat_ulong_t caddr, compat_ulong_t cdata)
910 {
911 	const struct user_regset_view *view = task_user_regset_view(current);
912 	compat_ulong_t caddr2 = task_pt_regs(current)->u_regs[UREG_I4];
913 	struct pt_regs32 __user *pregs;
914 	struct compat_fps __user *fps;
915 	unsigned long addr2 = caddr2;
916 	unsigned long addr = caddr;
917 	unsigned long data = cdata;
918 	int ret;
919 
920 	pregs = (struct pt_regs32 __user *) addr;
921 	fps = (struct compat_fps __user *) addr;
922 
923 	switch (request) {
924 	case PTRACE_PEEKUSR:
925 		ret = (addr != 0) ? -EIO : 0;
926 		break;
927 
928 	case PTRACE_GETREGS:
929 		ret = copy_regset_to_user(child, view, REGSET_GENERAL,
930 					  32 * sizeof(u32),
931 					  4 * sizeof(u32),
932 					  &pregs->psr);
933 		if (!ret)
934 			ret = copy_regset_to_user(child, view, REGSET_GENERAL,
935 						  1 * sizeof(u32),
936 						  15 * sizeof(u32),
937 						  &pregs->u_regs[0]);
938 		break;
939 
940 	case PTRACE_SETREGS:
941 		ret = copy_regset_from_user(child, view, REGSET_GENERAL,
942 					    32 * sizeof(u32),
943 					    4 * sizeof(u32),
944 					    &pregs->psr);
945 		if (!ret)
946 			ret = copy_regset_from_user(child, view, REGSET_GENERAL,
947 						    1 * sizeof(u32),
948 						    15 * sizeof(u32),
949 						    &pregs->u_regs[0]);
950 		break;
951 
952 	case PTRACE_GETFPREGS:
953 		ret = copy_regset_to_user(child, view, REGSET_FP,
954 					  0 * sizeof(u32),
955 					  32 * sizeof(u32),
956 					  &fps->regs[0]);
957 		if (!ret)
958 			ret = copy_regset_to_user(child, view, REGSET_FP,
959 						  33 * sizeof(u32),
960 						  1 * sizeof(u32),
961 						  &fps->fsr);
962 		if (!ret) {
963 			if (__put_user(0, &fps->flags) ||
964 			    __put_user(0, &fps->extra) ||
965 			    __put_user(0, &fps->fpqd) ||
966 			    clear_user(&fps->fpq[0], 32 * sizeof(unsigned int)))
967 				ret = -EFAULT;
968 		}
969 		break;
970 
971 	case PTRACE_SETFPREGS:
972 		ret = copy_regset_from_user(child, view, REGSET_FP,
973 					    0 * sizeof(u32),
974 					    32 * sizeof(u32),
975 					    &fps->regs[0]);
976 		if (!ret)
977 			ret = copy_regset_from_user(child, view, REGSET_FP,
978 						    33 * sizeof(u32),
979 						    1 * sizeof(u32),
980 						    &fps->fsr);
981 		break;
982 
983 	case PTRACE_READTEXT:
984 	case PTRACE_READDATA:
985 		ret = ptrace_readdata(child, addr,
986 				      (char __user *)addr2, data);
987 		if (ret == data)
988 			ret = 0;
989 		else if (ret >= 0)
990 			ret = -EIO;
991 		break;
992 
993 	case PTRACE_WRITETEXT:
994 	case PTRACE_WRITEDATA:
995 		ret = ptrace_writedata(child, (char __user *) addr2,
996 				       addr, data);
997 		if (ret == data)
998 			ret = 0;
999 		else if (ret >= 0)
1000 			ret = -EIO;
1001 		break;
1002 
1003 	default:
1004 		if (request == PTRACE_SPARC_DETACH)
1005 			request = PTRACE_DETACH;
1006 		ret = compat_ptrace_request(child, request, addr, data);
1007 		break;
1008 	}
1009 
1010 	return ret;
1011 }
1012 #endif /* CONFIG_COMPAT */
1013 
1014 struct fps {
1015 	unsigned int regs[64];
1016 	unsigned long fsr;
1017 };
1018 
1019 long arch_ptrace(struct task_struct *child, long request,
1020 		 unsigned long addr, unsigned long data)
1021 {
1022 	const struct user_regset_view *view = task_user_regset_view(current);
1023 	unsigned long addr2 = task_pt_regs(current)->u_regs[UREG_I4];
1024 	struct pt_regs __user *pregs;
1025 	struct fps __user *fps;
1026 	void __user *addr2p;
1027 	int ret;
1028 
1029 	pregs = (struct pt_regs __user *) addr;
1030 	fps = (struct fps __user *) addr;
1031 	addr2p = (void __user *) addr2;
1032 
1033 	switch (request) {
1034 	case PTRACE_PEEKUSR:
1035 		ret = (addr != 0) ? -EIO : 0;
1036 		break;
1037 
1038 	case PTRACE_GETREGS64:
1039 		ret = copy_regset_to_user(child, view, REGSET_GENERAL,
1040 					  1 * sizeof(u64),
1041 					  15 * sizeof(u64),
1042 					  &pregs->u_regs[0]);
1043 		if (!ret) {
1044 			/* XXX doesn't handle 'y' register correctly XXX */
1045 			ret = copy_regset_to_user(child, view, REGSET_GENERAL,
1046 						  32 * sizeof(u64),
1047 						  4 * sizeof(u64),
1048 						  &pregs->tstate);
1049 		}
1050 		break;
1051 
1052 	case PTRACE_SETREGS64:
1053 		ret = copy_regset_from_user(child, view, REGSET_GENERAL,
1054 					    1 * sizeof(u64),
1055 					    15 * sizeof(u64),
1056 					    &pregs->u_regs[0]);
1057 		if (!ret) {
1058 			/* XXX doesn't handle 'y' register correctly XXX */
1059 			ret = copy_regset_from_user(child, view, REGSET_GENERAL,
1060 						    32 * sizeof(u64),
1061 						    4 * sizeof(u64),
1062 						    &pregs->tstate);
1063 		}
1064 		break;
1065 
1066 	case PTRACE_GETFPREGS64:
1067 		ret = copy_regset_to_user(child, view, REGSET_FP,
1068 					  0 * sizeof(u64),
1069 					  33 * sizeof(u64),
1070 					  fps);
1071 		break;
1072 
1073 	case PTRACE_SETFPREGS64:
1074 		ret = copy_regset_from_user(child, view, REGSET_FP,
1075 					  0 * sizeof(u64),
1076 					  33 * sizeof(u64),
1077 					  fps);
1078 		break;
1079 
1080 	case PTRACE_READTEXT:
1081 	case PTRACE_READDATA:
1082 		ret = ptrace_readdata(child, addr, addr2p, data);
1083 		if (ret == data)
1084 			ret = 0;
1085 		else if (ret >= 0)
1086 			ret = -EIO;
1087 		break;
1088 
1089 	case PTRACE_WRITETEXT:
1090 	case PTRACE_WRITEDATA:
1091 		ret = ptrace_writedata(child, addr2p, addr, data);
1092 		if (ret == data)
1093 			ret = 0;
1094 		else if (ret >= 0)
1095 			ret = -EIO;
1096 		break;
1097 
1098 	default:
1099 		if (request == PTRACE_SPARC_DETACH)
1100 			request = PTRACE_DETACH;
1101 		ret = ptrace_request(child, request, addr, data);
1102 		break;
1103 	}
1104 
1105 	return ret;
1106 }
1107 
1108 asmlinkage int syscall_trace_enter(struct pt_regs *regs)
1109 {
1110 	int ret = 0;
1111 
1112 	/* do the secure computing check first */
1113 	secure_computing_strict(regs->u_regs[UREG_G1]);
1114 
1115 	if (test_thread_flag(TIF_NOHZ))
1116 		user_exit();
1117 
1118 	if (test_thread_flag(TIF_SYSCALL_TRACE))
1119 		ret = tracehook_report_syscall_entry(regs);
1120 
1121 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1122 		trace_sys_enter(regs, regs->u_regs[UREG_G1]);
1123 
1124 	audit_syscall_entry(regs->u_regs[UREG_G1], regs->u_regs[UREG_I0],
1125 			    regs->u_regs[UREG_I1], regs->u_regs[UREG_I2],
1126 			    regs->u_regs[UREG_I3]);
1127 
1128 	return ret;
1129 }
1130 
1131 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1132 {
1133 	if (test_thread_flag(TIF_NOHZ))
1134 		user_exit();
1135 
1136 	audit_syscall_exit(regs);
1137 
1138 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1139 		trace_sys_exit(regs, regs->u_regs[UREG_I0]);
1140 
1141 	if (test_thread_flag(TIF_SYSCALL_TRACE))
1142 		tracehook_report_syscall_exit(regs, 0);
1143 
1144 	if (test_thread_flag(TIF_NOHZ))
1145 		user_enter();
1146 }
1147 
1148 /**
1149  * regs_query_register_offset() - query register offset from its name
1150  * @name:	the name of a register
1151  *
1152  * regs_query_register_offset() returns the offset of a register in struct
1153  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
1154  */
1155 int regs_query_register_offset(const char *name)
1156 {
1157 	const struct pt_regs_offset *roff;
1158 
1159 	for (roff = regoffset_table; roff->name != NULL; roff++)
1160 		if (!strcmp(roff->name, name))
1161 			return roff->offset;
1162 	return -EINVAL;
1163 }
1164