xref: /linux/arch/sparc/kernel/ptrace_64.c (revision c16c8bfa09d5f318c1bd65698d058d3739970c24)
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 <trace/syscall.h>
29 #include <linux/compat.h>
30 #include <linux/elf.h>
31 #include <linux/context_tracking.h>
32 
33 #include <asm/asi.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 			 struct membuf to)
249 {
250 	const struct pt_regs *regs = task_pt_regs(target);
251 	struct reg_window window;
252 
253 	if (target == current)
254 		flushw_user();
255 
256 	membuf_write(&to, regs->u_regs, 16 * sizeof(u64));
257 	if (!to.left)
258 		return 0;
259 	if (regwindow64_get(target, regs, &window))
260 		return -EFAULT;
261 	membuf_write(&to, &window, 16 * sizeof(u64));
262 	/* TSTATE, TPC, TNPC */
263 	membuf_write(&to, &regs->tstate, 3 * sizeof(u64));
264 	return membuf_store(&to, (u64)regs->y);
265 }
266 
267 static int genregs64_set(struct task_struct *target,
268 			 const struct user_regset *regset,
269 			 unsigned int pos, unsigned int count,
270 			 const void *kbuf, const void __user *ubuf)
271 {
272 	struct pt_regs *regs = task_pt_regs(target);
273 	int ret;
274 
275 	if (target == current)
276 		flushw_user();
277 
278 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
279 				 regs->u_regs,
280 				 0, 16 * sizeof(u64));
281 	if (!ret && count && pos < (32 * sizeof(u64))) {
282 		struct reg_window window;
283 
284 		if (regwindow64_get(target, regs, &window))
285 			return -EFAULT;
286 
287 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
288 					 &window,
289 					 16 * sizeof(u64),
290 					 32 * sizeof(u64));
291 
292 		if (!ret &&
293 		    regwindow64_set(target, regs, &window))
294 			return -EFAULT;
295 	}
296 
297 	if (!ret && count > 0) {
298 		unsigned long tstate;
299 
300 		/* TSTATE */
301 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
302 					 &tstate,
303 					 32 * sizeof(u64),
304 					 33 * sizeof(u64));
305 		if (!ret) {
306 			/* Only the condition codes and the "in syscall"
307 			 * state can be modified in the %tstate register.
308 			 */
309 			tstate &= (TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
310 			regs->tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
311 			regs->tstate |= tstate;
312 		}
313 	}
314 
315 	if (!ret) {
316 		/* TPC, TNPC */
317 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
318 					 &regs->tpc,
319 					 33 * sizeof(u64),
320 					 35 * sizeof(u64));
321 	}
322 
323 	if (!ret) {
324 		unsigned long y = regs->y;
325 
326 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
327 					 &y,
328 					 35 * sizeof(u64),
329 					 36 * sizeof(u64));
330 		if (!ret)
331 			regs->y = y;
332 	}
333 
334 	if (!ret)
335 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
336 						36 * sizeof(u64), -1);
337 
338 	return ret;
339 }
340 
341 static int fpregs64_get(struct task_struct *target,
342 			const struct user_regset *regset,
343 			struct membuf to)
344 {
345 	struct thread_info *t = task_thread_info(target);
346 	unsigned long fprs;
347 
348 	if (target == current)
349 		save_and_clear_fpu();
350 
351 	fprs = t->fpsaved[0];
352 
353 	if (fprs & FPRS_DL)
354 		membuf_write(&to, t->fpregs, 16 * sizeof(u64));
355 	else
356 		membuf_zero(&to, 16 * sizeof(u64));
357 
358 	if (fprs & FPRS_DU)
359 		membuf_write(&to, t->fpregs + 16, 16 * sizeof(u64));
360 	else
361 		membuf_zero(&to, 16 * sizeof(u64));
362 	if (fprs & FPRS_FEF) {
363 		membuf_store(&to, t->xfsr[0]);
364 		membuf_store(&to, t->gsr[0]);
365 	} else {
366 		membuf_zero(&to, 2 * sizeof(u64));
367 	}
368 	return membuf_store(&to, fprs);
369 }
370 
371 static int fpregs64_set(struct task_struct *target,
372 			const struct user_regset *regset,
373 			unsigned int pos, unsigned int count,
374 			const void *kbuf, const void __user *ubuf)
375 {
376 	unsigned long *fpregs = task_thread_info(target)->fpregs;
377 	unsigned long fprs;
378 	int ret;
379 
380 	if (target == current)
381 		save_and_clear_fpu();
382 
383 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
384 				 fpregs,
385 				 0, 32 * sizeof(u64));
386 	if (!ret)
387 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
388 					 task_thread_info(target)->xfsr,
389 					 32 * sizeof(u64),
390 					 33 * sizeof(u64));
391 	if (!ret)
392 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
393 					 task_thread_info(target)->gsr,
394 					 33 * sizeof(u64),
395 					 34 * sizeof(u64));
396 
397 	fprs = task_thread_info(target)->fpsaved[0];
398 	if (!ret && count > 0) {
399 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
400 					 &fprs,
401 					 34 * sizeof(u64),
402 					 35 * sizeof(u64));
403 	}
404 
405 	fprs |= (FPRS_FEF | FPRS_DL | FPRS_DU);
406 	task_thread_info(target)->fpsaved[0] = fprs;
407 
408 	if (!ret)
409 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
410 						35 * sizeof(u64), -1);
411 	return ret;
412 }
413 
414 static const struct user_regset sparc64_regsets[] = {
415 	/* Format is:
416 	 * 	G0 --> G7
417 	 *	O0 --> O7
418 	 *	L0 --> L7
419 	 *	I0 --> I7
420 	 *	TSTATE, TPC, TNPC, Y
421 	 */
422 	[REGSET_GENERAL] = {
423 		.core_note_type = NT_PRSTATUS,
424 		.n = 36,
425 		.size = sizeof(u64), .align = sizeof(u64),
426 		.regset_get = genregs64_get, .set = genregs64_set
427 	},
428 	/* Format is:
429 	 *	F0 --> F63
430 	 *	FSR
431 	 *	GSR
432 	 *	FPRS
433 	 */
434 	[REGSET_FP] = {
435 		.core_note_type = NT_PRFPREG,
436 		.n = 35,
437 		.size = sizeof(u64), .align = sizeof(u64),
438 		.regset_get = fpregs64_get, .set = fpregs64_set
439 	},
440 };
441 
442 static int getregs64_get(struct task_struct *target,
443 			 const struct user_regset *regset,
444 			 struct membuf to)
445 {
446 	const struct pt_regs *regs = task_pt_regs(target);
447 
448 	if (target == current)
449 		flushw_user();
450 
451 	membuf_write(&to, regs->u_regs + 1, 15 * sizeof(u64));
452 	membuf_store(&to, (u64)0);
453 	membuf_write(&to, &regs->tstate, 3 * sizeof(u64));
454 	return membuf_store(&to, (u64)regs->y);
455 }
456 
457 static int setregs64_set(struct task_struct *target,
458 			 const struct user_regset *regset,
459 			 unsigned int pos, unsigned int count,
460 			 const void *kbuf, const void __user *ubuf)
461 {
462 	struct pt_regs *regs = task_pt_regs(target);
463 	unsigned long y = regs->y;
464 	unsigned long tstate;
465 	int ret;
466 
467 	if (target == current)
468 		flushw_user();
469 
470 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
471 				 regs->u_regs + 1,
472 				 0 * sizeof(u64),
473 				 15 * sizeof(u64));
474 	if (ret)
475 		return ret;
476 	ret =user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
477 				 15 * sizeof(u64), 16 * sizeof(u64));
478 	if (ret)
479 		return ret;
480 	/* TSTATE */
481 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
482 				 &tstate,
483 				 16 * sizeof(u64),
484 				 17 * sizeof(u64));
485 	if (ret)
486 		return ret;
487 	/* Only the condition codes and the "in syscall"
488 	 * state can be modified in the %tstate register.
489 	 */
490 	tstate &= (TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
491 	regs->tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
492 	regs->tstate |= tstate;
493 
494 	/* TPC, TNPC */
495 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
496 				 &regs->tpc,
497 				 17 * sizeof(u64),
498 				 19 * sizeof(u64));
499 	if (ret)
500 		return ret;
501 	/* Y */
502 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
503 				 &y,
504 				 19 * sizeof(u64),
505 				 20 * sizeof(u64));
506 	if (!ret)
507 		regs->y = y;
508 	return ret;
509 }
510 
511 static const struct user_regset ptrace64_regsets[] = {
512 	/* Format is:
513 	 *      G1 --> G7
514 	 *      O0 --> O7
515 	 *	0
516 	 *      TSTATE, TPC, TNPC, Y
517 	 */
518 	[REGSET_GENERAL] = {
519 		.n = 20, .size = sizeof(u64),
520 		.regset_get = getregs64_get, .set = setregs64_set,
521 	},
522 };
523 
524 static const struct user_regset_view ptrace64_view = {
525 	.regsets = ptrace64_regsets, .n = ARRAY_SIZE(ptrace64_regsets)
526 };
527 
528 static const struct user_regset_view user_sparc64_view = {
529 	.name = "sparc64", .e_machine = EM_SPARCV9,
530 	.regsets = sparc64_regsets, .n = ARRAY_SIZE(sparc64_regsets)
531 };
532 
533 #ifdef CONFIG_COMPAT
534 static int genregs32_get(struct task_struct *target,
535 			 const struct user_regset *regset,
536 			 struct membuf to)
537 {
538 	const struct pt_regs *regs = task_pt_regs(target);
539 	u32 uregs[16];
540 	int i;
541 
542 	if (target == current)
543 		flushw_user();
544 
545 	for (i = 0; i < 16; i++)
546 		membuf_store(&to, (u32)regs->u_regs[i]);
547 	if (!to.left)
548 		return 0;
549 	if (get_from_target(target, regs->u_regs[UREG_I6],
550 			    uregs, sizeof(uregs)))
551 		return -EFAULT;
552 	membuf_write(&to, uregs, 16 * sizeof(u32));
553 	membuf_store(&to, (u32)tstate_to_psr(regs->tstate));
554 	membuf_store(&to, (u32)(regs->tpc));
555 	membuf_store(&to, (u32)(regs->tnpc));
556 	membuf_store(&to, (u32)(regs->y));
557 	return membuf_zero(&to, 2 * sizeof(u32));
558 }
559 
560 static int genregs32_set(struct task_struct *target,
561 			 const struct user_regset *regset,
562 			 unsigned int pos, unsigned int count,
563 			 const void *kbuf, const void __user *ubuf)
564 {
565 	struct pt_regs *regs = task_pt_regs(target);
566 	compat_ulong_t __user *reg_window;
567 	const compat_ulong_t *k = kbuf;
568 	const compat_ulong_t __user *u = ubuf;
569 	compat_ulong_t reg;
570 
571 	if (target == current)
572 		flushw_user();
573 
574 	pos /= sizeof(reg);
575 	count /= sizeof(reg);
576 
577 	if (kbuf) {
578 		for (; count > 0 && pos < 16; count--)
579 			regs->u_regs[pos++] = *k++;
580 
581 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
582 		reg_window -= 16;
583 		if (target == current) {
584 			for (; count > 0 && pos < 32; count--) {
585 				if (put_user(*k++, &reg_window[pos++]))
586 					return -EFAULT;
587 			}
588 		} else {
589 			for (; count > 0 && pos < 32; count--) {
590 				if (access_process_vm(target,
591 						      (unsigned long)
592 						      &reg_window[pos],
593 						      (void *) k,
594 						      sizeof(*k),
595 						      FOLL_FORCE | FOLL_WRITE)
596 				    != sizeof(*k))
597 					return -EFAULT;
598 				k++;
599 				pos++;
600 			}
601 		}
602 	} else {
603 		for (; count > 0 && pos < 16; count--) {
604 			if (get_user(reg, u++))
605 				return -EFAULT;
606 			regs->u_regs[pos++] = reg;
607 		}
608 
609 		reg_window = (compat_ulong_t __user *) regs->u_regs[UREG_I6];
610 		reg_window -= 16;
611 		if (target == current) {
612 			for (; count > 0 && pos < 32; count--) {
613 				if (get_user(reg, u++) ||
614 				    put_user(reg, &reg_window[pos++]))
615 					return -EFAULT;
616 			}
617 		} else {
618 			for (; count > 0 && pos < 32; count--) {
619 				if (get_user(reg, u++))
620 					return -EFAULT;
621 				if (access_process_vm(target,
622 						      (unsigned long)
623 						      &reg_window[pos],
624 						      &reg, sizeof(reg),
625 						      FOLL_FORCE | FOLL_WRITE)
626 				    != sizeof(reg))
627 					return -EFAULT;
628 				pos++;
629 				u++;
630 			}
631 		}
632 	}
633 	while (count > 0) {
634 		unsigned long tstate;
635 
636 		if (kbuf)
637 			reg = *k++;
638 		else if (get_user(reg, u++))
639 			return -EFAULT;
640 
641 		switch (pos) {
642 		case 32: /* PSR */
643 			tstate = regs->tstate;
644 			tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
645 			tstate |= psr_to_tstate_icc(reg);
646 			if (reg & PSR_SYSCALL)
647 				tstate |= TSTATE_SYSCALL;
648 			regs->tstate = tstate;
649 			break;
650 		case 33: /* PC */
651 			regs->tpc = reg;
652 			break;
653 		case 34: /* NPC */
654 			regs->tnpc = reg;
655 			break;
656 		case 35: /* Y */
657 			regs->y = reg;
658 			break;
659 		case 36: /* WIM */
660 		case 37: /* TBR */
661 			break;
662 		default:
663 			goto finish;
664 		}
665 
666 		pos++;
667 		count--;
668 	}
669 finish:
670 	pos *= sizeof(reg);
671 	count *= sizeof(reg);
672 
673 	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
674 					 38 * sizeof(reg), -1);
675 }
676 
677 static int fpregs32_get(struct task_struct *target,
678 			const struct user_regset *regset,
679 			struct membuf to)
680 {
681 	struct thread_info *t = task_thread_info(target);
682 	bool enabled;
683 
684 	if (target == current)
685 		save_and_clear_fpu();
686 
687 	enabled = t->fpsaved[0] & FPRS_FEF;
688 
689 	membuf_write(&to, t->fpregs, 32 * sizeof(u32));
690 	membuf_zero(&to, sizeof(u32));
691 	if (enabled)
692 		membuf_store(&to, (u32)t->xfsr[0]);
693 	else
694 		membuf_zero(&to, sizeof(u32));
695 	membuf_store(&to, (u32)((enabled << 8) | (8 << 16)));
696 	return membuf_zero(&to, 64 * sizeof(u32));
697 }
698 
699 static int fpregs32_set(struct task_struct *target,
700 			const struct user_regset *regset,
701 			unsigned int pos, unsigned int count,
702 			const void *kbuf, const void __user *ubuf)
703 {
704 	unsigned long *fpregs = task_thread_info(target)->fpregs;
705 	unsigned long fprs;
706 	int ret;
707 
708 	if (target == current)
709 		save_and_clear_fpu();
710 
711 	fprs = task_thread_info(target)->fpsaved[0];
712 
713 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
714 				 fpregs,
715 				 0, 32 * sizeof(u32));
716 	if (!ret)
717 		user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
718 					  32 * sizeof(u32),
719 					  33 * sizeof(u32));
720 	if (!ret && count > 0) {
721 		compat_ulong_t fsr;
722 		unsigned long val;
723 
724 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
725 					 &fsr,
726 					 33 * sizeof(u32),
727 					 34 * sizeof(u32));
728 		if (!ret) {
729 			val = task_thread_info(target)->xfsr[0];
730 			val &= 0xffffffff00000000UL;
731 			val |= fsr;
732 			task_thread_info(target)->xfsr[0] = val;
733 		}
734 	}
735 
736 	fprs |= (FPRS_FEF | FPRS_DL);
737 	task_thread_info(target)->fpsaved[0] = fprs;
738 
739 	if (!ret)
740 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
741 						34 * sizeof(u32), -1);
742 	return ret;
743 }
744 
745 static const struct user_regset sparc32_regsets[] = {
746 	/* Format is:
747 	 * 	G0 --> G7
748 	 *	O0 --> O7
749 	 *	L0 --> L7
750 	 *	I0 --> I7
751 	 *	PSR, PC, nPC, Y, WIM, TBR
752 	 */
753 	[REGSET_GENERAL] = {
754 		.core_note_type = NT_PRSTATUS,
755 		.n = 38,
756 		.size = sizeof(u32), .align = sizeof(u32),
757 		.regset_get = genregs32_get, .set = genregs32_set
758 	},
759 	/* Format is:
760 	 *	F0 --> F31
761 	 *	empty 32-bit word
762 	 *	FSR (32--bit word)
763 	 *	FPU QUEUE COUNT (8-bit char)
764 	 *	FPU QUEUE ENTRYSIZE (8-bit char)
765 	 *	FPU ENABLED (8-bit char)
766 	 *	empty 8-bit char
767 	 *	FPU QUEUE (64 32-bit ints)
768 	 */
769 	[REGSET_FP] = {
770 		.core_note_type = NT_PRFPREG,
771 		.n = 99,
772 		.size = sizeof(u32), .align = sizeof(u32),
773 		.regset_get = fpregs32_get, .set = fpregs32_set
774 	},
775 };
776 
777 static int getregs_get(struct task_struct *target,
778 			 const struct user_regset *regset,
779 			 struct membuf to)
780 {
781 	const struct pt_regs *regs = task_pt_regs(target);
782 	int i;
783 
784 	if (target == current)
785 		flushw_user();
786 
787 	membuf_store(&to, (u32)tstate_to_psr(regs->tstate));
788 	membuf_store(&to, (u32)(regs->tpc));
789 	membuf_store(&to, (u32)(regs->tnpc));
790 	membuf_store(&to, (u32)(regs->y));
791 	for (i = 1; i < 16; i++)
792 		membuf_store(&to, (u32)regs->u_regs[i]);
793 	return to.left;
794 }
795 
796 static int setregs_set(struct task_struct *target,
797 			 const struct user_regset *regset,
798 			 unsigned int pos, unsigned int count,
799 			 const void *kbuf, const void __user *ubuf)
800 {
801 	struct pt_regs *regs = task_pt_regs(target);
802 	unsigned long tstate;
803 	u32 uregs[19];
804 	int i, ret;
805 
806 	if (target == current)
807 		flushw_user();
808 
809 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
810 				 uregs,
811 				 0, 19 * sizeof(u32));
812 	if (ret)
813 		return ret;
814 
815 	tstate = regs->tstate;
816 	tstate &= ~(TSTATE_ICC | TSTATE_XCC | TSTATE_SYSCALL);
817 	tstate |= psr_to_tstate_icc(uregs[0]);
818 	if (uregs[0] & PSR_SYSCALL)
819 		tstate |= TSTATE_SYSCALL;
820 	regs->tstate = tstate;
821 	regs->tpc = uregs[1];
822 	regs->tnpc = uregs[2];
823 	regs->y = uregs[3];
824 
825 	for (i = 1; i < 15; i++)
826 		regs->u_regs[i] = uregs[3 + i];
827 	return 0;
828 }
829 
830 static int getfpregs_get(struct task_struct *target,
831 			const struct user_regset *regset,
832 			struct membuf to)
833 {
834 	struct thread_info *t = task_thread_info(target);
835 
836 	if (target == current)
837 		save_and_clear_fpu();
838 
839 	membuf_write(&to, t->fpregs, 32 * sizeof(u32));
840 	if (t->fpsaved[0] & FPRS_FEF)
841 		membuf_store(&to, (u32)t->xfsr[0]);
842 	else
843 		membuf_zero(&to, sizeof(u32));
844 	return membuf_zero(&to, 35 * sizeof(u32));
845 }
846 
847 static int setfpregs_set(struct task_struct *target,
848 			const struct user_regset *regset,
849 			unsigned int pos, unsigned int count,
850 			const void *kbuf, const void __user *ubuf)
851 {
852 	unsigned long *fpregs = task_thread_info(target)->fpregs;
853 	unsigned long fprs;
854 	int ret;
855 
856 	if (target == current)
857 		save_and_clear_fpu();
858 
859 	fprs = task_thread_info(target)->fpsaved[0];
860 
861 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
862 				 fpregs,
863 				 0, 32 * sizeof(u32));
864 	if (!ret) {
865 		compat_ulong_t fsr;
866 		unsigned long val;
867 
868 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
869 					 &fsr,
870 					 32 * sizeof(u32),
871 					 33 * sizeof(u32));
872 		if (!ret) {
873 			val = task_thread_info(target)->xfsr[0];
874 			val &= 0xffffffff00000000UL;
875 			val |= fsr;
876 			task_thread_info(target)->xfsr[0] = val;
877 		}
878 	}
879 
880 	fprs |= (FPRS_FEF | FPRS_DL);
881 	task_thread_info(target)->fpsaved[0] = fprs;
882 	return ret;
883 }
884 
885 static const struct user_regset ptrace32_regsets[] = {
886 	[REGSET_GENERAL] = {
887 		.n = 19, .size = sizeof(u32),
888 		.regset_get = getregs_get, .set = setregs_set,
889 	},
890 	[REGSET_FP] = {
891 		.n = 68, .size = sizeof(u32),
892 		.regset_get = getfpregs_get, .set = setfpregs_set,
893 	},
894 };
895 
896 static const struct user_regset_view ptrace32_view = {
897 	.regsets = ptrace32_regsets, .n = ARRAY_SIZE(ptrace32_regsets)
898 };
899 
900 static const struct user_regset_view user_sparc32_view = {
901 	.name = "sparc", .e_machine = EM_SPARC,
902 	.regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
903 };
904 #endif /* CONFIG_COMPAT */
905 
906 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
907 {
908 #ifdef CONFIG_COMPAT
909 	if (test_tsk_thread_flag(task, TIF_32BIT))
910 		return &user_sparc32_view;
911 #endif
912 	return &user_sparc64_view;
913 }
914 
915 #ifdef CONFIG_COMPAT
916 struct compat_fps {
917 	unsigned int regs[32];
918 	unsigned int fsr;
919 	unsigned int flags;
920 	unsigned int extra;
921 	unsigned int fpqd;
922 	struct compat_fq {
923 		unsigned int insnaddr;
924 		unsigned int insn;
925 	} fpq[16];
926 };
927 
928 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
929 			compat_ulong_t caddr, compat_ulong_t cdata)
930 {
931 	compat_ulong_t caddr2 = task_pt_regs(current)->u_regs[UREG_I4];
932 	struct pt_regs32 __user *pregs;
933 	struct compat_fps __user *fps;
934 	unsigned long addr2 = caddr2;
935 	unsigned long addr = caddr;
936 	unsigned long data = cdata;
937 	int ret;
938 
939 	pregs = (struct pt_regs32 __user *) addr;
940 	fps = (struct compat_fps __user *) addr;
941 
942 	switch (request) {
943 	case PTRACE_PEEKUSR:
944 		ret = (addr != 0) ? -EIO : 0;
945 		break;
946 
947 	case PTRACE_GETREGS:
948 		ret = copy_regset_to_user(child, &ptrace32_view,
949 					  REGSET_GENERAL, 0,
950 					  19 * sizeof(u32),
951 					  pregs);
952 		break;
953 
954 	case PTRACE_SETREGS:
955 		ret = copy_regset_from_user(child, &ptrace32_view,
956 					  REGSET_GENERAL, 0,
957 					  19 * sizeof(u32),
958 					  pregs);
959 		break;
960 
961 	case PTRACE_GETFPREGS:
962 		ret = copy_regset_to_user(child, &ptrace32_view,
963 					  REGSET_FP, 0,
964 					  68 * sizeof(u32),
965 					  fps);
966 		break;
967 
968 	case PTRACE_SETFPREGS:
969 		ret = copy_regset_from_user(child, &ptrace32_view,
970 					  REGSET_FP, 0,
971 					  33 * sizeof(u32),
972 					  fps);
973 		break;
974 
975 	case PTRACE_READTEXT:
976 	case PTRACE_READDATA:
977 		ret = ptrace_readdata(child, addr,
978 				      (char __user *)addr2, data);
979 		if (ret == data)
980 			ret = 0;
981 		else if (ret >= 0)
982 			ret = -EIO;
983 		break;
984 
985 	case PTRACE_WRITETEXT:
986 	case PTRACE_WRITEDATA:
987 		ret = ptrace_writedata(child, (char __user *) addr2,
988 				       addr, data);
989 		if (ret == data)
990 			ret = 0;
991 		else if (ret >= 0)
992 			ret = -EIO;
993 		break;
994 
995 	default:
996 		if (request == PTRACE_SPARC_DETACH)
997 			request = PTRACE_DETACH;
998 		ret = compat_ptrace_request(child, request, addr, data);
999 		break;
1000 	}
1001 
1002 	return ret;
1003 }
1004 #endif /* CONFIG_COMPAT */
1005 
1006 struct fps {
1007 	unsigned int regs[64];
1008 	unsigned long fsr;
1009 };
1010 
1011 long arch_ptrace(struct task_struct *child, long request,
1012 		 unsigned long addr, unsigned long data)
1013 {
1014 	const struct user_regset_view *view = task_user_regset_view(current);
1015 	unsigned long addr2 = task_pt_regs(current)->u_regs[UREG_I4];
1016 	struct pt_regs __user *pregs;
1017 	struct fps __user *fps;
1018 	void __user *addr2p;
1019 	int ret;
1020 
1021 	pregs = (struct pt_regs __user *) addr;
1022 	fps = (struct fps __user *) addr;
1023 	addr2p = (void __user *) addr2;
1024 
1025 	switch (request) {
1026 	case PTRACE_PEEKUSR:
1027 		ret = (addr != 0) ? -EIO : 0;
1028 		break;
1029 
1030 	case PTRACE_GETREGS64:
1031 		ret = copy_regset_to_user(child, &ptrace64_view,
1032 					  REGSET_GENERAL, 0,
1033 					  19 * sizeof(u64),
1034 					  pregs);
1035 		break;
1036 
1037 	case PTRACE_SETREGS64:
1038 		ret = copy_regset_from_user(child, &ptrace64_view,
1039 					  REGSET_GENERAL, 0,
1040 					  19 * sizeof(u64),
1041 					  pregs);
1042 		break;
1043 
1044 	case PTRACE_GETFPREGS64:
1045 		ret = copy_regset_to_user(child, view, REGSET_FP,
1046 					  0 * sizeof(u64),
1047 					  33 * sizeof(u64),
1048 					  fps);
1049 		break;
1050 
1051 	case PTRACE_SETFPREGS64:
1052 		ret = copy_regset_from_user(child, view, REGSET_FP,
1053 					  0 * sizeof(u64),
1054 					  33 * sizeof(u64),
1055 					  fps);
1056 		break;
1057 
1058 	case PTRACE_READTEXT:
1059 	case PTRACE_READDATA:
1060 		ret = ptrace_readdata(child, addr, addr2p, data);
1061 		if (ret == data)
1062 			ret = 0;
1063 		else if (ret >= 0)
1064 			ret = -EIO;
1065 		break;
1066 
1067 	case PTRACE_WRITETEXT:
1068 	case PTRACE_WRITEDATA:
1069 		ret = ptrace_writedata(child, addr2p, addr, data);
1070 		if (ret == data)
1071 			ret = 0;
1072 		else if (ret >= 0)
1073 			ret = -EIO;
1074 		break;
1075 
1076 	default:
1077 		if (request == PTRACE_SPARC_DETACH)
1078 			request = PTRACE_DETACH;
1079 		ret = ptrace_request(child, request, addr, data);
1080 		break;
1081 	}
1082 
1083 	return ret;
1084 }
1085 
1086 asmlinkage int syscall_trace_enter(struct pt_regs *regs)
1087 {
1088 	int ret = 0;
1089 
1090 	/* do the secure computing check first */
1091 	secure_computing_strict(regs->u_regs[UREG_G1]);
1092 
1093 	if (test_thread_flag(TIF_NOHZ))
1094 		user_exit();
1095 
1096 	if (test_thread_flag(TIF_SYSCALL_TRACE))
1097 		ret = ptrace_report_syscall_entry(regs);
1098 
1099 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1100 		trace_sys_enter(regs, regs->u_regs[UREG_G1]);
1101 
1102 	audit_syscall_entry(regs->u_regs[UREG_G1], regs->u_regs[UREG_I0],
1103 			    regs->u_regs[UREG_I1], regs->u_regs[UREG_I2],
1104 			    regs->u_regs[UREG_I3]);
1105 
1106 	return ret;
1107 }
1108 
1109 asmlinkage void syscall_trace_leave(struct pt_regs *regs)
1110 {
1111 	if (test_thread_flag(TIF_NOHZ))
1112 		user_exit();
1113 
1114 	audit_syscall_exit(regs);
1115 
1116 	if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT)))
1117 		trace_sys_exit(regs, regs->u_regs[UREG_I0]);
1118 
1119 	if (test_thread_flag(TIF_SYSCALL_TRACE))
1120 		ptrace_report_syscall_exit(regs, 0);
1121 
1122 	if (test_thread_flag(TIF_NOHZ))
1123 		user_enter();
1124 }
1125 
1126 /**
1127  * regs_query_register_offset() - query register offset from its name
1128  * @name:	the name of a register
1129  *
1130  * regs_query_register_offset() returns the offset of a register in struct
1131  * pt_regs from its name. If the name is invalid, this returns -EINVAL;
1132  */
1133 int regs_query_register_offset(const char *name)
1134 {
1135 	const struct pt_regs_offset *roff;
1136 
1137 	for (roff = regoffset_table; roff->name != NULL; roff++)
1138 		if (!strcmp(roff->name, name))
1139 			return roff->offset;
1140 	return -EINVAL;
1141 }
1142 
1143 /**
1144  * regs_within_kernel_stack() - check the address in the stack
1145  * @regs:	pt_regs which contains kernel stack pointer.
1146  * @addr:	address which is checked.
1147  *
1148  * regs_within_kernel_stack() checks @addr is within the kernel stack page(s).
1149  * If @addr is within the kernel stack, it returns true. If not, returns false.
1150  */
1151 static inline int regs_within_kernel_stack(struct pt_regs *regs,
1152 					   unsigned long addr)
1153 {
1154 	unsigned long ksp = kernel_stack_pointer(regs) + STACK_BIAS;
1155 	return ((addr & ~(THREAD_SIZE - 1))  ==
1156 		(ksp & ~(THREAD_SIZE - 1)));
1157 }
1158 
1159 /**
1160  * regs_get_kernel_stack_nth() - get Nth entry of the stack
1161  * @regs:	pt_regs which contains kernel stack pointer.
1162  * @n:		stack entry number.
1163  *
1164  * regs_get_kernel_stack_nth() returns @n th entry of the kernel stack which
1165  * is specified by @regs. If the @n th entry is NOT in the kernel stack,
1166  * this returns 0.
1167  */
1168 unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n)
1169 {
1170 	unsigned long ksp = kernel_stack_pointer(regs) + STACK_BIAS;
1171 	unsigned long *addr = (unsigned long *)ksp;
1172 	addr += n;
1173 	if (regs_within_kernel_stack(regs, (unsigned long)addr))
1174 		return *addr;
1175 	else
1176 		return 0;
1177 }
1178