xref: /linux/arch/sparc/kernel/ptrace_64.c (revision b8d312aa075f33282565467662c4628dae0a2aff)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* ptrace.c: Sparc process tracing support.
3  *
4  * Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
5  * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
6  *
7  * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
8  * and David Mosberger.
9  *
10  * Added Linux support -miguel (weird, eh?, the original code was meant
11  * to emulate SunOS).
12  */
13 
14 #include <linux/kernel.h>
15 #include <linux/sched.h>
16 #include <linux/sched/task_stack.h>
17 #include <linux/mm.h>
18 #include <linux/errno.h>
19 #include <linux/export.h>
20 #include <linux/ptrace.h>
21 #include <linux/user.h>
22 #include <linux/smp.h>
23 #include <linux/security.h>
24 #include <linux/seccomp.h>
25 #include <linux/audit.h>
26 #include <linux/signal.h>
27 #include <linux/regset.h>
28 #include <linux/tracehook.h>
29 #include <trace/syscall.h>
30 #include <linux/compat.h>
31 #include <linux/elf.h>
32 #include <linux/context_tracking.h>
33 
34 #include <asm/asi.h>
35 #include <asm/pgtable.h>
36 #include <linux/uaccess.h>
37 #include <asm/psrcompat.h>
38 #include <asm/visasm.h>
39 #include <asm/spitfire.h>
40 #include <asm/page.h>
41 #include <asm/cpudata.h>
42 #include <asm/cacheflush.h>
43 
44 #define CREATE_TRACE_POINTS
45 #include <trace/events/syscalls.h>
46 
47 #include "entry.h"
48 
49 /* #define ALLOW_INIT_TRACING */
50 
51 struct pt_regs_offset {
52 	const char *name;
53 	int offset;
54 };
55 
56 #define REG_OFFSET_NAME(n, r) \
57 	{.name = n, .offset = (PT_V9_##r)}
58 #define REG_OFFSET_END {.name = NULL, .offset = 0}
59 
60 static const struct pt_regs_offset regoffset_table[] = {
61 	REG_OFFSET_NAME("g0", G0),
62 	REG_OFFSET_NAME("g1", G1),
63 	REG_OFFSET_NAME("g2", G2),
64 	REG_OFFSET_NAME("g3", G3),
65 	REG_OFFSET_NAME("g4", G4),
66 	REG_OFFSET_NAME("g5", G5),
67 	REG_OFFSET_NAME("g6", G6),
68 	REG_OFFSET_NAME("g7", G7),
69 
70 	REG_OFFSET_NAME("i0", I0),
71 	REG_OFFSET_NAME("i1", I1),
72 	REG_OFFSET_NAME("i2", I2),
73 	REG_OFFSET_NAME("i3", I3),
74 	REG_OFFSET_NAME("i4", I4),
75 	REG_OFFSET_NAME("i5", I5),
76 	REG_OFFSET_NAME("i6", I6),
77 	REG_OFFSET_NAME("i7", I7),
78 
79 	REG_OFFSET_NAME("tstate", TSTATE),
80 	REG_OFFSET_NAME("pc", TPC),
81 	REG_OFFSET_NAME("npc", TNPC),
82 	REG_OFFSET_NAME("y", Y),
83 	REG_OFFSET_NAME("lr", I7),
84 
85 	REG_OFFSET_END,
86 };
87 
88 /*
89  * Called by kernel/ptrace.c when detaching..
90  *
91  * Make sure single step bits etc are not set.
92  */
93 void ptrace_disable(struct task_struct *child)
94 {
95 	/* nothing to do */
96 }
97 
98 /* To get the necessary page struct, access_process_vm() first calls
99  * get_user_pages().  This has done a flush_dcache_page() on the
100  * accessed page.  Then our caller (copy_{to,from}_user_page()) did
101  * to memcpy to read/write the data from that page.
102  *
103  * Now, the only thing we have to do is:
104  * 1) flush the D-cache if it's possible than an illegal alias
105  *    has been created
106  * 2) flush the I-cache if this is pre-cheetah and we did a write
107  */
108 void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
109 			 unsigned long uaddr, void *kaddr,
110 			 unsigned long len, int write)
111 {
112 	BUG_ON(len > PAGE_SIZE);
113 
114 	if (tlb_type == hypervisor)
115 		return;
116 
117 	preempt_disable();
118 
119 #ifdef DCACHE_ALIASING_POSSIBLE
120 	/* If bit 13 of the kernel address we used to access the
121 	 * user page is the same as the virtual address that page
122 	 * is mapped to in the user's address space, we can skip the
123 	 * D-cache flush.
124 	 */
125 	if ((uaddr ^ (unsigned long) kaddr) & (1UL << 13)) {
126 		unsigned long start = __pa(kaddr);
127 		unsigned long end = start + len;
128 		unsigned long dcache_line_size;
129 
130 		dcache_line_size = local_cpu_data().dcache_line_size;
131 
132 		if (tlb_type == spitfire) {
133 			for (; start < end; start += dcache_line_size)
134 				spitfire_put_dcache_tag(start & 0x3fe0, 0x0);
135 		} else {
136 			start &= ~(dcache_line_size - 1);
137 			for (; start < end; start += dcache_line_size)
138 				__asm__ __volatile__(
139 					"stxa %%g0, [%0] %1\n\t"
140 					"membar #Sync"
141 					: /* no outputs */
142 					: "r" (start),
143 					"i" (ASI_DCACHE_INVALIDATE));
144 		}
145 	}
146 #endif
147 	if (write && tlb_type == spitfire) {
148 		unsigned long start = (unsigned long) kaddr;
149 		unsigned long end = start + len;
150 		unsigned long icache_line_size;
151 
152 		icache_line_size = local_cpu_data().icache_line_size;
153 
154 		for (; start < end; start += icache_line_size)
155 			flushi(start);
156 	}
157 
158 	preempt_enable();
159 }
160 EXPORT_SYMBOL_GPL(flush_ptrace_access);
161 
162 static int get_from_target(struct task_struct *target, unsigned long uaddr,
163 			   void *kbuf, int len)
164 {
165 	if (target == current) {
166 		if (copy_from_user(kbuf, (void __user *) uaddr, len))
167 			return -EFAULT;
168 	} else {
169 		int len2 = access_process_vm(target, uaddr, kbuf, len,
170 				FOLL_FORCE);
171 		if (len2 != len)
172 			return -EFAULT;
173 	}
174 	return 0;
175 }
176 
177 static int set_to_target(struct task_struct *target, unsigned long uaddr,
178 			 void *kbuf, int len)
179 {
180 	if (target == current) {
181 		if (copy_to_user((void __user *) uaddr, kbuf, len))
182 			return -EFAULT;
183 	} else {
184 		int len2 = access_process_vm(target, uaddr, kbuf, len,
185 				FOLL_FORCE | FOLL_WRITE);
186 		if (len2 != len)
187 			return -EFAULT;
188 	}
189 	return 0;
190 }
191 
192 static int regwindow64_get(struct task_struct *target,
193 			   const struct pt_regs *regs,
194 			   struct reg_window *wbuf)
195 {
196 	unsigned long rw_addr = regs->u_regs[UREG_I6];
197 
198 	if (!test_thread_64bit_stack(rw_addr)) {
199 		struct reg_window32 win32;
200 		int i;
201 
202 		if (get_from_target(target, rw_addr, &win32, sizeof(win32)))
203 			return -EFAULT;
204 		for (i = 0; i < 8; i++)
205 			wbuf->locals[i] = win32.locals[i];
206 		for (i = 0; i < 8; i++)
207 			wbuf->ins[i] = win32.ins[i];
208 	} else {
209 		rw_addr += STACK_BIAS;
210 		if (get_from_target(target, rw_addr, wbuf, sizeof(*wbuf)))
211 			return -EFAULT;
212 	}
213 
214 	return 0;
215 }
216 
217 static int regwindow64_set(struct task_struct *target,
218 			   const struct pt_regs *regs,
219 			   struct reg_window *wbuf)
220 {
221 	unsigned long rw_addr = regs->u_regs[UREG_I6];
222 
223 	if (!test_thread_64bit_stack(rw_addr)) {
224 		struct reg_window32 win32;
225 		int i;
226 
227 		for (i = 0; i < 8; i++)
228 			win32.locals[i] = wbuf->locals[i];
229 		for (i = 0; i < 8; i++)
230 			win32.ins[i] = wbuf->ins[i];
231 
232 		if (set_to_target(target, rw_addr, &win32, sizeof(win32)))
233 			return -EFAULT;
234 	} else {
235 		rw_addr += STACK_BIAS;
236 		if (set_to_target(target, rw_addr, wbuf, sizeof(*wbuf)))
237 			return -EFAULT;
238 	}
239 
240 	return 0;
241 }
242 
243 enum sparc_regset {
244 	REGSET_GENERAL,
245 	REGSET_FP,
246 };
247 
248 static int genregs64_get(struct task_struct *target,
249 			 const struct user_regset *regset,
250 			 unsigned int pos, unsigned int count,
251 			 void *kbuf, void __user *ubuf)
252 {
253 	const struct pt_regs *regs = task_pt_regs(target);
254 	int ret;
255 
256 	if (target == current)
257 		flushw_user();
258 
259 	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
260 				  regs->u_regs,
261 				  0, 16 * sizeof(u64));
262 	if (!ret && count && pos < (32 * sizeof(u64))) {
263 		struct reg_window window;
264 
265 		if (regwindow64_get(target, regs, &window))
266 			return -EFAULT;
267 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
268 					  &window,
269 					  16 * sizeof(u64),
270 					  32 * sizeof(u64));
271 	}
272 
273 	if (!ret) {
274 		/* TSTATE, TPC, TNPC */
275 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
276 					  &regs->tstate,
277 					  32 * sizeof(u64),
278 					  35 * sizeof(u64));
279 	}
280 
281 	if (!ret) {
282 		unsigned long y = regs->y;
283 
284 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
285 					  &y,
286 					  35 * sizeof(u64),
287 					  36 * sizeof(u64));
288 	}
289 
290 	if (!ret) {
291 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
292 					       36 * sizeof(u64), -1);
293 
294 	}
295 	return ret;
296 }
297 
298 static int genregs64_set(struct task_struct *target,
299 			 const struct user_regset *regset,
300 			 unsigned int pos, unsigned int count,
301 			 const void *kbuf, const void __user *ubuf)
302 {
303 	struct pt_regs *regs = task_pt_regs(target);
304 	int ret;
305 
306 	if (target == current)
307 		flushw_user();
308 
309 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
310 				 regs->u_regs,
311 				 0, 16 * sizeof(u64));
312 	if (!ret && count && pos < (32 * sizeof(u64))) {
313 		struct reg_window window;
314 
315 		if (regwindow64_get(target, regs, &window))
316 			return -EFAULT;
317 
318 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
319 					 &window,
320 					 16 * sizeof(u64),
321 					 32 * sizeof(u64));
322 
323 		if (!ret &&
324 		    regwindow64_set(target, regs, &window))
325 			return -EFAULT;
326 	}
327 
328 	if (!ret && count > 0) {
329 		unsigned long tstate;
330 
331 		/* TSTATE */
332 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
333 					 &tstate,
334 					 32 * sizeof(u64),
335 					 33 * sizeof(u64));
336 		if (!ret) {
337 			/* Only the condition codes and the "in syscall"
338 			 * state can be modified in the %tstate register.
339 			 */
340 			tstate &= (TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
341 			regs->tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
342 			regs->tstate |= tstate;
343 		}
344 	}
345 
346 	if (!ret) {
347 		/* TPC, TNPC */
348 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
349 					 &regs->tpc,
350 					 33 * sizeof(u64),
351 					 35 * sizeof(u64));
352 	}
353 
354 	if (!ret) {
355 		unsigned long y = regs->y;
356 
357 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
358 					 &y,
359 					 35 * sizeof(u64),
360 					 36 * sizeof(u64));
361 		if (!ret)
362 			regs->y = y;
363 	}
364 
365 	if (!ret)
366 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
367 						36 * sizeof(u64), -1);
368 
369 	return ret;
370 }
371 
372 static int fpregs64_get(struct task_struct *target,
373 			const struct user_regset *regset,
374 			unsigned int pos, unsigned int count,
375 			void *kbuf, void __user *ubuf)
376 {
377 	const unsigned long *fpregs = task_thread_info(target)->fpregs;
378 	unsigned long fprs, fsr, gsr;
379 	int ret;
380 
381 	if (target == current)
382 		save_and_clear_fpu();
383 
384 	fprs = task_thread_info(target)->fpsaved[0];
385 
386 	if (fprs & FPRS_DL)
387 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
388 					  fpregs,
389 					  0, 16 * sizeof(u64));
390 	else
391 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
392 					       0,
393 					       16 * sizeof(u64));
394 
395 	if (!ret) {
396 		if (fprs & FPRS_DU)
397 			ret = user_regset_copyout(&pos, &count,
398 						  &kbuf, &ubuf,
399 						  fpregs + 16,
400 						  16 * sizeof(u64),
401 						  32 * sizeof(u64));
402 		else
403 			ret = user_regset_copyout_zero(&pos, &count,
404 						       &kbuf, &ubuf,
405 						       16 * sizeof(u64),
406 						       32 * sizeof(u64));
407 	}
408 
409 	if (fprs & FPRS_FEF) {
410 		fsr = task_thread_info(target)->xfsr[0];
411 		gsr = task_thread_info(target)->gsr[0];
412 	} else {
413 		fsr = gsr = 0;
414 	}
415 
416 	if (!ret)
417 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
418 					  &fsr,
419 					  32 * sizeof(u64),
420 					  33 * sizeof(u64));
421 	if (!ret)
422 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
423 					  &gsr,
424 					  33 * sizeof(u64),
425 					  34 * sizeof(u64));
426 	if (!ret)
427 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
428 					  &fprs,
429 					  34 * sizeof(u64),
430 					  35 * sizeof(u64));
431 
432 	if (!ret)
433 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
434 					       35 * sizeof(u64), -1);
435 
436 	return ret;
437 }
438 
439 static int fpregs64_set(struct task_struct *target,
440 			const struct user_regset *regset,
441 			unsigned int pos, unsigned int count,
442 			const void *kbuf, const void __user *ubuf)
443 {
444 	unsigned long *fpregs = task_thread_info(target)->fpregs;
445 	unsigned long fprs;
446 	int ret;
447 
448 	if (target == current)
449 		save_and_clear_fpu();
450 
451 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
452 				 fpregs,
453 				 0, 32 * sizeof(u64));
454 	if (!ret)
455 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
456 					 task_thread_info(target)->xfsr,
457 					 32 * sizeof(u64),
458 					 33 * sizeof(u64));
459 	if (!ret)
460 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
461 					 task_thread_info(target)->gsr,
462 					 33 * sizeof(u64),
463 					 34 * sizeof(u64));
464 
465 	fprs = task_thread_info(target)->fpsaved[0];
466 	if (!ret && count > 0) {
467 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
468 					 &fprs,
469 					 34 * sizeof(u64),
470 					 35 * sizeof(u64));
471 	}
472 
473 	fprs |= (FPRS_FEF | FPRS_DL | FPRS_DU);
474 	task_thread_info(target)->fpsaved[0] = fprs;
475 
476 	if (!ret)
477 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
478 						35 * sizeof(u64), -1);
479 	return ret;
480 }
481 
482 static const struct user_regset sparc64_regsets[] = {
483 	/* Format is:
484 	 * 	G0 --> G7
485 	 *	O0 --> O7
486 	 *	L0 --> L7
487 	 *	I0 --> I7
488 	 *	TSTATE, TPC, TNPC, Y
489 	 */
490 	[REGSET_GENERAL] = {
491 		.core_note_type = NT_PRSTATUS,
492 		.n = 36,
493 		.size = sizeof(u64), .align = sizeof(u64),
494 		.get = genregs64_get, .set = genregs64_set
495 	},
496 	/* Format is:
497 	 *	F0 --> F63
498 	 *	FSR
499 	 *	GSR
500 	 *	FPRS
501 	 */
502 	[REGSET_FP] = {
503 		.core_note_type = NT_PRFPREG,
504 		.n = 35,
505 		.size = sizeof(u64), .align = sizeof(u64),
506 		.get = fpregs64_get, .set = fpregs64_set
507 	},
508 };
509 
510 static const struct user_regset_view user_sparc64_view = {
511 	.name = "sparc64", .e_machine = EM_SPARCV9,
512 	.regsets = sparc64_regsets, .n = ARRAY_SIZE(sparc64_regsets)
513 };
514 
515 #ifdef CONFIG_COMPAT
516 static int genregs32_get(struct task_struct *target,
517 			 const struct user_regset *regset,
518 			 unsigned int pos, unsigned int count,
519 			 void *kbuf, void __user *ubuf)
520 {
521 	const struct pt_regs *regs = task_pt_regs(target);
522 	compat_ulong_t __user *reg_window;
523 	compat_ulong_t *k = kbuf;
524 	compat_ulong_t __user *u = ubuf;
525 	compat_ulong_t reg;
526 
527 	if (target == current)
528 		flushw_user();
529 
530 	pos /= sizeof(reg);
531 	count /= sizeof(reg);
532 
533 	if (kbuf) {
534 		for (; count > 0 && pos < 16; count--)
535 			*k++ = regs->u_regs[pos++];
536 
537 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
538 		reg_window -= 16;
539 		if (target == current) {
540 			for (; count > 0 && pos < 32; count--) {
541 				if (get_user(*k++, &reg_window[pos++]))
542 					return -EFAULT;
543 			}
544 		} else {
545 			for (; count > 0 && pos < 32; count--) {
546 				if (access_process_vm(target,
547 						      (unsigned long)
548 						      &reg_window[pos],
549 						      k, sizeof(*k),
550 						      FOLL_FORCE)
551 				    != sizeof(*k))
552 					return -EFAULT;
553 				k++;
554 				pos++;
555 			}
556 		}
557 	} else {
558 		for (; count > 0 && pos < 16; count--) {
559 			if (put_user((compat_ulong_t) regs->u_regs[pos++], u++))
560 				return -EFAULT;
561 		}
562 
563 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
564 		reg_window -= 16;
565 		if (target == current) {
566 			for (; count > 0 && pos < 32; count--) {
567 				if (get_user(reg, &reg_window[pos++]) ||
568 				    put_user(reg, u++))
569 					return -EFAULT;
570 			}
571 		} else {
572 			for (; count > 0 && pos < 32; count--) {
573 				if (access_process_vm(target,
574 						      (unsigned long)
575 						      &reg_window[pos],
576 						      &reg, sizeof(reg),
577 						      FOLL_FORCE)
578 				    != sizeof(reg))
579 					return -EFAULT;
580 				if (access_process_vm(target,
581 						      (unsigned long) u,
582 						      &reg, sizeof(reg),
583 						      FOLL_FORCE | FOLL_WRITE)
584 				    != sizeof(reg))
585 					return -EFAULT;
586 				pos++;
587 				u++;
588 			}
589 		}
590 	}
591 	while (count > 0) {
592 		switch (pos) {
593 		case 32: /* PSR */
594 			reg = tstate_to_psr(regs->tstate);
595 			break;
596 		case 33: /* PC */
597 			reg = regs->tpc;
598 			break;
599 		case 34: /* NPC */
600 			reg = regs->tnpc;
601 			break;
602 		case 35: /* Y */
603 			reg = regs->y;
604 			break;
605 		case 36: /* WIM */
606 		case 37: /* TBR */
607 			reg = 0;
608 			break;
609 		default:
610 			goto finish;
611 		}
612 
613 		if (kbuf)
614 			*k++ = reg;
615 		else if (put_user(reg, u++))
616 			return -EFAULT;
617 		pos++;
618 		count--;
619 	}
620 finish:
621 	pos *= sizeof(reg);
622 	count *= sizeof(reg);
623 
624 	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
625 					38 * sizeof(reg), -1);
626 }
627 
628 static int genregs32_set(struct task_struct *target,
629 			 const struct user_regset *regset,
630 			 unsigned int pos, unsigned int count,
631 			 const void *kbuf, const void __user *ubuf)
632 {
633 	struct pt_regs *regs = task_pt_regs(target);
634 	compat_ulong_t __user *reg_window;
635 	const compat_ulong_t *k = kbuf;
636 	const compat_ulong_t __user *u = ubuf;
637 	compat_ulong_t reg;
638 
639 	if (target == current)
640 		flushw_user();
641 
642 	pos /= sizeof(reg);
643 	count /= sizeof(reg);
644 
645 	if (kbuf) {
646 		for (; count > 0 && pos < 16; count--)
647 			regs->u_regs[pos++] = *k++;
648 
649 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
650 		reg_window -= 16;
651 		if (target == current) {
652 			for (; count > 0 && pos < 32; count--) {
653 				if (put_user(*k++, &reg_window[pos++]))
654 					return -EFAULT;
655 			}
656 		} else {
657 			for (; count > 0 && pos < 32; count--) {
658 				if (access_process_vm(target,
659 						      (unsigned long)
660 						      &reg_window[pos],
661 						      (void *) k,
662 						      sizeof(*k),
663 						      FOLL_FORCE | FOLL_WRITE)
664 				    != sizeof(*k))
665 					return -EFAULT;
666 				k++;
667 				pos++;
668 			}
669 		}
670 	} else {
671 		for (; count > 0 && pos < 16; count--) {
672 			if (get_user(reg, u++))
673 				return -EFAULT;
674 			regs->u_regs[pos++] = reg;
675 		}
676 
677 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
678 		reg_window -= 16;
679 		if (target == current) {
680 			for (; count > 0 && pos < 32; count--) {
681 				if (get_user(reg, u++) ||
682 				    put_user(reg, &reg_window[pos++]))
683 					return -EFAULT;
684 			}
685 		} else {
686 			for (; count > 0 && pos < 32; count--) {
687 				if (access_process_vm(target,
688 						      (unsigned long)
689 						      u,
690 						      &reg, sizeof(reg),
691 						      FOLL_FORCE)
692 				    != sizeof(reg))
693 					return -EFAULT;
694 				if (access_process_vm(target,
695 						      (unsigned long)
696 						      &reg_window[pos],
697 						      &reg, sizeof(reg),
698 						      FOLL_FORCE | FOLL_WRITE)
699 				    != sizeof(reg))
700 					return -EFAULT;
701 				pos++;
702 				u++;
703 			}
704 		}
705 	}
706 	while (count > 0) {
707 		unsigned long tstate;
708 
709 		if (kbuf)
710 			reg = *k++;
711 		else if (get_user(reg, u++))
712 			return -EFAULT;
713 
714 		switch (pos) {
715 		case 32: /* PSR */
716 			tstate = regs->tstate;
717 			tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
718 			tstate |= psr_to_tstate_icc(reg);
719 			if (reg & PSR_SYSCALL)
720 				tstate |= TSTATE_SYSCALL;
721 			regs->tstate = tstate;
722 			break;
723 		case 33: /* PC */
724 			regs->tpc = reg;
725 			break;
726 		case 34: /* NPC */
727 			regs->tnpc = reg;
728 			break;
729 		case 35: /* Y */
730 			regs->y = reg;
731 			break;
732 		case 36: /* WIM */
733 		case 37: /* TBR */
734 			break;
735 		default:
736 			goto finish;
737 		}
738 
739 		pos++;
740 		count--;
741 	}
742 finish:
743 	pos *= sizeof(reg);
744 	count *= sizeof(reg);
745 
746 	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
747 					 38 * sizeof(reg), -1);
748 }
749 
750 static int fpregs32_get(struct task_struct *target,
751 			const struct user_regset *regset,
752 			unsigned int pos, unsigned int count,
753 			void *kbuf, void __user *ubuf)
754 {
755 	const unsigned long *fpregs = task_thread_info(target)->fpregs;
756 	compat_ulong_t enabled;
757 	unsigned long fprs;
758 	compat_ulong_t fsr;
759 	int ret = 0;
760 
761 	if (target == current)
762 		save_and_clear_fpu();
763 
764 	fprs = task_thread_info(target)->fpsaved[0];
765 	if (fprs & FPRS_FEF) {
766 		fsr = task_thread_info(target)->xfsr[0];
767 		enabled = 1;
768 	} else {
769 		fsr = 0;
770 		enabled = 0;
771 	}
772 
773 	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
774 				  fpregs,
775 				  0, 32 * sizeof(u32));
776 
777 	if (!ret)
778 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
779 					       32 * sizeof(u32),
780 					       33 * sizeof(u32));
781 	if (!ret)
782 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
783 					  &fsr,
784 					  33 * sizeof(u32),
785 					  34 * sizeof(u32));
786 
787 	if (!ret) {
788 		compat_ulong_t val;
789 
790 		val = (enabled << 8) | (8 << 16);
791 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
792 					  &val,
793 					  34 * sizeof(u32),
794 					  35 * sizeof(u32));
795 	}
796 
797 	if (!ret)
798 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
799 					       35 * sizeof(u32), -1);
800 
801 	return ret;
802 }
803 
804 static int fpregs32_set(struct task_struct *target,
805 			const struct user_regset *regset,
806 			unsigned int pos, unsigned int count,
807 			const void *kbuf, const void __user *ubuf)
808 {
809 	unsigned long *fpregs = task_thread_info(target)->fpregs;
810 	unsigned long fprs;
811 	int ret;
812 
813 	if (target == current)
814 		save_and_clear_fpu();
815 
816 	fprs = task_thread_info(target)->fpsaved[0];
817 
818 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
819 				 fpregs,
820 				 0, 32 * sizeof(u32));
821 	if (!ret)
822 		user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
823 					  32 * sizeof(u32),
824 					  33 * sizeof(u32));
825 	if (!ret && count > 0) {
826 		compat_ulong_t fsr;
827 		unsigned long val;
828 
829 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
830 					 &fsr,
831 					 33 * sizeof(u32),
832 					 34 * sizeof(u32));
833 		if (!ret) {
834 			val = task_thread_info(target)->xfsr[0];
835 			val &= 0xffffffff00000000UL;
836 			val |= fsr;
837 			task_thread_info(target)->xfsr[0] = val;
838 		}
839 	}
840 
841 	fprs |= (FPRS_FEF | FPRS_DL);
842 	task_thread_info(target)->fpsaved[0] = fprs;
843 
844 	if (!ret)
845 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
846 						34 * sizeof(u32), -1);
847 	return ret;
848 }
849 
850 static const struct user_regset sparc32_regsets[] = {
851 	/* Format is:
852 	 * 	G0 --> G7
853 	 *	O0 --> O7
854 	 *	L0 --> L7
855 	 *	I0 --> I7
856 	 *	PSR, PC, nPC, Y, WIM, TBR
857 	 */
858 	[REGSET_GENERAL] = {
859 		.core_note_type = NT_PRSTATUS,
860 		.n = 38,
861 		.size = sizeof(u32), .align = sizeof(u32),
862 		.get = genregs32_get, .set = genregs32_set
863 	},
864 	/* Format is:
865 	 *	F0 --> F31
866 	 *	empty 32-bit word
867 	 *	FSR (32--bit word)
868 	 *	FPU QUEUE COUNT (8-bit char)
869 	 *	FPU QUEUE ENTRYSIZE (8-bit char)
870 	 *	FPU ENABLED (8-bit char)
871 	 *	empty 8-bit char
872 	 *	FPU QUEUE (64 32-bit ints)
873 	 */
874 	[REGSET_FP] = {
875 		.core_note_type = NT_PRFPREG,
876 		.n = 99,
877 		.size = sizeof(u32), .align = sizeof(u32),
878 		.get = fpregs32_get, .set = fpregs32_set
879 	},
880 };
881 
882 static const struct user_regset_view user_sparc32_view = {
883 	.name = "sparc", .e_machine = EM_SPARC,
884 	.regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
885 };
886 #endif /* CONFIG_COMPAT */
887 
888 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
889 {
890 #ifdef CONFIG_COMPAT
891 	if (test_tsk_thread_flag(task, TIF_32BIT))
892 		return &user_sparc32_view;
893 #endif
894 	return &user_sparc64_view;
895 }
896 
897 #ifdef CONFIG_COMPAT
898 struct compat_fps {
899 	unsigned int regs[32];
900 	unsigned int fsr;
901 	unsigned int flags;
902 	unsigned int extra;
903 	unsigned int fpqd;
904 	struct compat_fq {
905 		unsigned int insnaddr;
906 		unsigned int insn;
907 	} fpq[16];
908 };
909 
910 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
911 			compat_ulong_t caddr, compat_ulong_t cdata)
912 {
913 	const struct user_regset_view *view = task_user_regset_view(current);
914 	compat_ulong_t caddr2 = task_pt_regs(current)->u_regs[UREG_I4];
915 	struct pt_regs32 __user *pregs;
916 	struct compat_fps __user *fps;
917 	unsigned long addr2 = caddr2;
918 	unsigned long addr = caddr;
919 	unsigned long data = cdata;
920 	int ret;
921 
922 	pregs = (struct pt_regs32 __user *) addr;
923 	fps = (struct compat_fps __user *) addr;
924 
925 	switch (request) {
926 	case PTRACE_PEEKUSR:
927 		ret = (addr != 0) ? -EIO : 0;
928 		break;
929 
930 	case PTRACE_GETREGS:
931 		ret = copy_regset_to_user(child, view, REGSET_GENERAL,
932 					  32 * sizeof(u32),
933 					  4 * sizeof(u32),
934 					  &pregs->psr);
935 		if (!ret)
936 			ret = copy_regset_to_user(child, view, REGSET_GENERAL,
937 						  1 * sizeof(u32),
938 						  15 * sizeof(u32),
939 						  &pregs->u_regs[0]);
940 		break;
941 
942 	case PTRACE_SETREGS:
943 		ret = copy_regset_from_user(child, view, REGSET_GENERAL,
944 					    32 * sizeof(u32),
945 					    4 * sizeof(u32),
946 					    &pregs->psr);
947 		if (!ret)
948 			ret = copy_regset_from_user(child, view, REGSET_GENERAL,
949 						    1 * sizeof(u32),
950 						    15 * sizeof(u32),
951 						    &pregs->u_regs[0]);
952 		break;
953 
954 	case PTRACE_GETFPREGS:
955 		ret = copy_regset_to_user(child, view, REGSET_FP,
956 					  0 * sizeof(u32),
957 					  32 * sizeof(u32),
958 					  &fps->regs[0]);
959 		if (!ret)
960 			ret = copy_regset_to_user(child, view, REGSET_FP,
961 						  33 * sizeof(u32),
962 						  1 * sizeof(u32),
963 						  &fps->fsr);
964 		if (!ret) {
965 			if (__put_user(0, &fps->flags) ||
966 			    __put_user(0, &fps->extra) ||
967 			    __put_user(0, &fps->fpqd) ||
968 			    clear_user(&fps->fpq[0], 32 * sizeof(unsigned int)))
969 				ret = -EFAULT;
970 		}
971 		break;
972 
973 	case PTRACE_SETFPREGS:
974 		ret = copy_regset_from_user(child, view, REGSET_FP,
975 					    0 * sizeof(u32),
976 					    32 * sizeof(u32),
977 					    &fps->regs[0]);
978 		if (!ret)
979 			ret = copy_regset_from_user(child, view, REGSET_FP,
980 						    33 * sizeof(u32),
981 						    1 * sizeof(u32),
982 						    &fps->fsr);
983 		break;
984 
985 	case PTRACE_READTEXT:
986 	case PTRACE_READDATA:
987 		ret = ptrace_readdata(child, addr,
988 				      (char __user *)addr2, data);
989 		if (ret == data)
990 			ret = 0;
991 		else if (ret >= 0)
992 			ret = -EIO;
993 		break;
994 
995 	case PTRACE_WRITETEXT:
996 	case PTRACE_WRITEDATA:
997 		ret = ptrace_writedata(child, (char __user *) addr2,
998 				       addr, data);
999 		if (ret == data)
1000 			ret = 0;
1001 		else if (ret >= 0)
1002 			ret = -EIO;
1003 		break;
1004 
1005 	default:
1006 		if (request == PTRACE_SPARC_DETACH)
1007 			request = PTRACE_DETACH;
1008 		ret = compat_ptrace_request(child, request, addr, data);
1009 		break;
1010 	}
1011 
1012 	return ret;
1013 }
1014 #endif /* CONFIG_COMPAT */
1015 
1016 struct fps {
1017 	unsigned int regs[64];
1018 	unsigned long fsr;
1019 };
1020 
1021 long arch_ptrace(struct task_struct *child, long request,
1022 		 unsigned long addr, unsigned long data)
1023 {
1024 	const struct user_regset_view *view = task_user_regset_view(current);
1025 	unsigned long addr2 = task_pt_regs(current)->u_regs[UREG_I4];
1026 	struct pt_regs __user *pregs;
1027 	struct fps __user *fps;
1028 	void __user *addr2p;
1029 	int ret;
1030 
1031 	pregs = (struct pt_regs __user *) addr;
1032 	fps = (struct fps __user *) addr;
1033 	addr2p = (void __user *) addr2;
1034 
1035 	switch (request) {
1036 	case PTRACE_PEEKUSR:
1037 		ret = (addr != 0) ? -EIO : 0;
1038 		break;
1039 
1040 	case PTRACE_GETREGS64:
1041 		ret = copy_regset_to_user(child, view, REGSET_GENERAL,
1042 					  1 * sizeof(u64),
1043 					  15 * sizeof(u64),
1044 					  &pregs->u_regs[0]);
1045 		if (!ret) {
1046 			/* XXX doesn't handle 'y' register correctly XXX */
1047 			ret = copy_regset_to_user(child, view, REGSET_GENERAL,
1048 						  32 * sizeof(u64),
1049 						  4 * sizeof(u64),
1050 						  &pregs->tstate);
1051 		}
1052 		break;
1053 
1054 	case PTRACE_SETREGS64:
1055 		ret = copy_regset_from_user(child, view, REGSET_GENERAL,
1056 					    1 * sizeof(u64),
1057 					    15 * sizeof(u64),
1058 					    &pregs->u_regs[0]);
1059 		if (!ret) {
1060 			/* XXX doesn't handle 'y' register correctly XXX */
1061 			ret = copy_regset_from_user(child, view, REGSET_GENERAL,
1062 						    32 * sizeof(u64),
1063 						    4 * sizeof(u64),
1064 						    &pregs->tstate);
1065 		}
1066 		break;
1067 
1068 	case PTRACE_GETFPREGS64:
1069 		ret = copy_regset_to_user(child, view, REGSET_FP,
1070 					  0 * sizeof(u64),
1071 					  33 * sizeof(u64),
1072 					  fps);
1073 		break;
1074 
1075 	case PTRACE_SETFPREGS64:
1076 		ret = copy_regset_from_user(child, view, REGSET_FP,
1077 					  0 * sizeof(u64),
1078 					  33 * sizeof(u64),
1079 					  fps);
1080 		break;
1081 
1082 	case PTRACE_READTEXT:
1083 	case PTRACE_READDATA:
1084 		ret = ptrace_readdata(child, addr, addr2p, data);
1085 		if (ret == data)
1086 			ret = 0;
1087 		else if (ret >= 0)
1088 			ret = -EIO;
1089 		break;
1090 
1091 	case PTRACE_WRITETEXT:
1092 	case PTRACE_WRITEDATA:
1093 		ret = ptrace_writedata(child, addr2p, addr, data);
1094 		if (ret == data)
1095 			ret = 0;
1096 		else if (ret >= 0)
1097 			ret = -EIO;
1098 		break;
1099 
1100 	default:
1101 		if (request == PTRACE_SPARC_DETACH)
1102 			request = PTRACE_DETACH;
1103 		ret = ptrace_request(child, request, addr, data);
1104 		break;
1105 	}
1106 
1107 	return ret;
1108 }
1109 
1110 asmlinkage int syscall_trace_enter(struct pt_regs *regs)
1111 {
1112 	int ret = 0;
1113 
1114 	/* do the secure computing check first */
1115 	secure_computing_strict(regs->u_regs[UREG_G1]);
1116 
1117 	if (test_thread_flag(TIF_NOHZ))
1118 		user_exit();
1119 
1120 	if (test_thread_flag(TIF_SYSCALL_TRACE))
1121 		ret = tracehook_report_syscall_entry(regs);
1122 
1123 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1124 		trace_sys_enter(regs, regs->u_regs[UREG_G1]);
1125 
1126 	audit_syscall_entry(regs->u_regs[UREG_G1], regs->u_regs[UREG_I0],
1127 			    regs->u_regs[UREG_I1], regs->u_regs[UREG_I2],
1128 			    regs->u_regs[UREG_I3]);
1129 
1130 	return ret;
1131 }
1132 
1133 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1134 {
1135 	if (test_thread_flag(TIF_NOHZ))
1136 		user_exit();
1137 
1138 	audit_syscall_exit(regs);
1139 
1140 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1141 		trace_sys_exit(regs, regs->u_regs[UREG_I0]);
1142 
1143 	if (test_thread_flag(TIF_SYSCALL_TRACE))
1144 		tracehook_report_syscall_exit(regs, 0);
1145 
1146 	if (test_thread_flag(TIF_NOHZ))
1147 		user_enter();
1148 }
1149 
1150 /**
1151  * regs_query_register_offset() - query register offset from its name
1152  * @name:	the name of a register
1153  *
1154  * regs_query_register_offset() returns the offset of a register in struct
1155  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
1156  */
1157 int regs_query_register_offset(const char *name)
1158 {
1159 	const struct pt_regs_offset *roff;
1160 
1161 	for (roff = regoffset_table; roff->name != NULL; roff++)
1162 		if (!strcmp(roff->name, name))
1163 			return roff->offset;
1164 	return -EINVAL;
1165 }
1166 
1167 /**
1168  * regs_within_kernel_stack() - check the address in the stack
1169  * @regs:	pt_regs which contains kernel stack pointer.
1170  * @addr:	address which is checked.
1171  *
1172  * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
1173  * If @addr is within the kernel stack, it returns true. If not, returns false.
1174  */
1175 static inline int regs_within_kernel_stack(struct pt_regs *regs,
1176 					   unsigned long addr)
1177 {
1178 	unsigned long ksp = kernel_stack_pointer(regs) + STACK_BIAS;
1179 	return ((addr & ~(THREAD_SIZE - 1))  ==
1180 		(ksp & ~(THREAD_SIZE - 1)));
1181 }
1182 
1183 /**
1184  * regs_get_kernel_stack_nth() - get Nth entry of the stack
1185  * @regs:	pt_regs which contains kernel stack pointer.
1186  * @n:		stack entry number.
1187  *
1188  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1189  * is specified by @regs. If the @n th entry is NOT in the kernel stack,
1190  * this returns 0.
1191  */
1192 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1193 {
1194 	unsigned long ksp = kernel_stack_pointer(regs) + STACK_BIAS;
1195 	unsigned long *addr = (unsigned long *)ksp;
1196 	addr += n;
1197 	if (regs_within_kernel_stack(regs, (unsigned long)addr))
1198 		return *addr;
1199 	else
1200 		return 0;
1201 }
1202