1/* ptrace.c: Sparc process tracing support.
2 *
3 * Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
4 *
5 * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
6 * and David Mosberger.
7 *
8 * Added Linux support -miguel (weird, eh?, the original code was meant
9 * to emulate SunOS).
10 */
11
12#include <linux/kernel.h>
13#include <linux/sched.h>
14#include <linux/mm.h>
15#include <linux/errno.h>
16#include <linux/ptrace.h>
17#include <linux/user.h>
18#include <linux/smp.h>
19#include <linux/security.h>
20#include <linux/signal.h>
21#include <linux/regset.h>
22#include <linux/elf.h>
23#include <linux/tracehook.h>
24
25#include <asm/pgtable.h>
26#include <asm/uaccess.h>
27#include <asm/cacheflush.h>
28
29#include "kernel.h"
30
31/* #define ALLOW_INIT_TRACING */
32
33/*
34 * Called by kernel/ptrace.c when detaching..
35 *
36 * Make sure single step bits etc are not set.
37 */
38void ptrace_disable(struct task_struct *child)
39{
40	/* nothing to do */
41}
42
43enum sparc_regset {
44	REGSET_GENERAL,
45	REGSET_FP,
46};
47
48static int genregs32_get(struct task_struct *target,
49			 const struct user_regset *regset,
50			 unsigned int pos, unsigned int count,
51			 void *kbuf, void __user *ubuf)
52{
53	const struct pt_regs *regs = target->thread.kregs;
54	unsigned long __user *reg_window;
55	unsigned long *k = kbuf;
56	unsigned long __user *u = ubuf;
57	unsigned long reg;
58
59	if (target == current)
60		flush_user_windows();
61
62	pos /= sizeof(reg);
63	count /= sizeof(reg);
64
65	if (kbuf) {
66		for (; count > 0 && pos < 16; count--)
67			*k++ = regs->u_regs[pos++];
68
69		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
70		reg_window -= 16;
71		for (; count > 0 && pos < 32; count--) {
72			if (get_user(*k++, &reg_window[pos++]))
73				return -EFAULT;
74		}
75	} else {
76		for (; count > 0 && pos < 16; count--) {
77			if (put_user(regs->u_regs[pos++], u++))
78				return -EFAULT;
79		}
80
81		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
82		reg_window -= 16;
83		for (; count > 0 && pos < 32; count--) {
84			if (get_user(reg, &reg_window[pos++]) ||
85			    put_user(reg, u++))
86				return -EFAULT;
87		}
88	}
89	while (count > 0) {
90		switch (pos) {
91		case 32: /* PSR */
92			reg = regs->psr;
93			break;
94		case 33: /* PC */
95			reg = regs->pc;
96			break;
97		case 34: /* NPC */
98			reg = regs->npc;
99			break;
100		case 35: /* Y */
101			reg = regs->y;
102			break;
103		case 36: /* WIM */
104		case 37: /* TBR */
105			reg = 0;
106			break;
107		default:
108			goto finish;
109		}
110
111		if (kbuf)
112			*k++ = reg;
113		else if (put_user(reg, u++))
114			return -EFAULT;
115		pos++;
116		count--;
117	}
118finish:
119	pos *= sizeof(reg);
120	count *= sizeof(reg);
121
122	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
123					38 * sizeof(reg), -1);
124}
125
126static int genregs32_set(struct task_struct *target,
127			 const struct user_regset *regset,
128			 unsigned int pos, unsigned int count,
129			 const void *kbuf, const void __user *ubuf)
130{
131	struct pt_regs *regs = target->thread.kregs;
132	unsigned long __user *reg_window;
133	const unsigned long *k = kbuf;
134	const unsigned long __user *u = ubuf;
135	unsigned long reg;
136
137	if (target == current)
138		flush_user_windows();
139
140	pos /= sizeof(reg);
141	count /= sizeof(reg);
142
143	if (kbuf) {
144		for (; count > 0 && pos < 16; count--)
145			regs->u_regs[pos++] = *k++;
146
147		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
148		reg_window -= 16;
149		for (; count > 0 && pos < 32; count--) {
150			if (put_user(*k++, &reg_window[pos++]))
151				return -EFAULT;
152		}
153	} else {
154		for (; count > 0 && pos < 16; count--) {
155			if (get_user(reg, u++))
156				return -EFAULT;
157			regs->u_regs[pos++] = reg;
158		}
159
160		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
161		reg_window -= 16;
162		for (; count > 0 && pos < 32; count--) {
163			if (get_user(reg, u++) ||
164			    put_user(reg, &reg_window[pos++]))
165				return -EFAULT;
166		}
167	}
168	while (count > 0) {
169		unsigned long psr;
170
171		if (kbuf)
172			reg = *k++;
173		else if (get_user(reg, u++))
174			return -EFAULT;
175
176		switch (pos) {
177		case 32: /* PSR */
178			psr = regs->psr;
179			psr &= ~(PSR_ICC | PSR_SYSCALL);
180			psr |= (reg & (PSR_ICC | PSR_SYSCALL));
181			regs->psr = psr;
182			break;
183		case 33: /* PC */
184			regs->pc = reg;
185			break;
186		case 34: /* NPC */
187			regs->npc = reg;
188			break;
189		case 35: /* Y */
190			regs->y = reg;
191			break;
192		case 36: /* WIM */
193		case 37: /* TBR */
194			break;
195		default:
196			goto finish;
197		}
198
199		pos++;
200		count--;
201	}
202finish:
203	pos *= sizeof(reg);
204	count *= sizeof(reg);
205
206	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
207					 38 * sizeof(reg), -1);
208}
209
210static int fpregs32_get(struct task_struct *target,
211			const struct user_regset *regset,
212			unsigned int pos, unsigned int count,
213			void *kbuf, void __user *ubuf)
214{
215	const unsigned long *fpregs = target->thread.float_regs;
216	int ret = 0;
217
218#if 0
219	if (target == current)
220		save_and_clear_fpu();
221#endif
222
223	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
224				  fpregs,
225				  0, 32 * sizeof(u32));
226
227	if (!ret)
228		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
229					       32 * sizeof(u32),
230					       33 * sizeof(u32));
231	if (!ret)
232		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
233					  &target->thread.fsr,
234					  33 * sizeof(u32),
235					  34 * sizeof(u32));
236
237	if (!ret) {
238		unsigned long val;
239
240		val = (1 << 8) | (8 << 16);
241		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
242					  &val,
243					  34 * sizeof(u32),
244					  35 * sizeof(u32));
245	}
246
247	if (!ret)
248		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
249					       35 * sizeof(u32), -1);
250
251	return ret;
252}
253
254static int fpregs32_set(struct task_struct *target,
255			const struct user_regset *regset,
256			unsigned int pos, unsigned int count,
257			const void *kbuf, const void __user *ubuf)
258{
259	unsigned long *fpregs = target->thread.float_regs;
260	int ret;
261
262#if 0
263	if (target == current)
264		save_and_clear_fpu();
265#endif
266	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
267				 fpregs,
268				 0, 32 * sizeof(u32));
269	if (!ret)
270		user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
271					  32 * sizeof(u32),
272					  33 * sizeof(u32));
273	if (!ret && count > 0) {
274		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
275					 &target->thread.fsr,
276					 33 * sizeof(u32),
277					 34 * sizeof(u32));
278	}
279
280	if (!ret)
281		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
282						34 * sizeof(u32), -1);
283	return ret;
284}
285
286static const struct user_regset sparc32_regsets[] = {
287	/* Format is:
288	 * 	G0 --> G7
289	 *	O0 --> O7
290	 *	L0 --> L7
291	 *	I0 --> I7
292	 *	PSR, PC, nPC, Y, WIM, TBR
293	 */
294	[REGSET_GENERAL] = {
295		.core_note_type = NT_PRSTATUS,
296		.n = 38,
297		.size = sizeof(u32), .align = sizeof(u32),
298		.get = genregs32_get, .set = genregs32_set
299	},
300	/* Format is:
301	 *	F0 --> F31
302	 *	empty 32-bit word
303	 *	FSR (32--bit word)
304	 *	FPU QUEUE COUNT (8-bit char)
305	 *	FPU QUEUE ENTRYSIZE (8-bit char)
306	 *	FPU ENABLED (8-bit char)
307	 *	empty 8-bit char
308	 *	FPU QUEUE (64 32-bit ints)
309	 */
310	[REGSET_FP] = {
311		.core_note_type = NT_PRFPREG,
312		.n = 99,
313		.size = sizeof(u32), .align = sizeof(u32),
314		.get = fpregs32_get, .set = fpregs32_set
315	},
316};
317
318static const struct user_regset_view user_sparc32_view = {
319	.name = "sparc", .e_machine = EM_SPARC,
320	.regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
321};
322
323const struct user_regset_view *task_user_regset_view(struct task_struct *task)
324{
325	return &user_sparc32_view;
326}
327
328struct fps {
329	unsigned long regs[32];
330	unsigned long fsr;
331	unsigned long flags;
332	unsigned long extra;
333	unsigned long fpqd;
334	struct fq {
335		unsigned long *insnaddr;
336		unsigned long insn;
337	} fpq[16];
338};
339
340long arch_ptrace(struct task_struct *child, long request,
341		 unsigned long addr, unsigned long data)
342{
343	unsigned long addr2 = current->thread.kregs->u_regs[UREG_I4];
344	void __user *addr2p;
345	const struct user_regset_view *view;
346	struct pt_regs __user *pregs;
347	struct fps __user *fps;
348	int ret;
349
350	view = task_user_regset_view(current);
351	addr2p = (void __user *) addr2;
352	pregs = (struct pt_regs __user *) addr;
353	fps = (struct fps __user *) addr;
354
355	switch(request) {
356	case PTRACE_GETREGS: {
357		ret = copy_regset_to_user(child, view, REGSET_GENERAL,
358					  32 * sizeof(u32),
359					  4 * sizeof(u32),
360					  &pregs->psr);
361		if (!ret)
362			copy_regset_to_user(child, view, REGSET_GENERAL,
363					    1 * sizeof(u32),
364					    15 * sizeof(u32),
365					    &pregs->u_regs[0]);
366		break;
367	}
368
369	case PTRACE_SETREGS: {
370		ret = copy_regset_from_user(child, view, REGSET_GENERAL,
371					    32 * sizeof(u32),
372					    4 * sizeof(u32),
373					    &pregs->psr);
374		if (!ret)
375			copy_regset_from_user(child, view, REGSET_GENERAL,
376					      1 * sizeof(u32),
377					      15 * sizeof(u32),
378					      &pregs->u_regs[0]);
379		break;
380	}
381
382	case PTRACE_GETFPREGS: {
383		ret = copy_regset_to_user(child, view, REGSET_FP,
384					  0 * sizeof(u32),
385					  32 * sizeof(u32),
386					  &fps->regs[0]);
387		if (!ret)
388			ret = copy_regset_to_user(child, view, REGSET_FP,
389						  33 * sizeof(u32),
390						  1 * sizeof(u32),
391						  &fps->fsr);
392
393		if (!ret) {
394			if (__put_user(0, &fps->fpqd) ||
395			    __put_user(0, &fps->flags) ||
396			    __put_user(0, &fps->extra) ||
397			    clear_user(fps->fpq, sizeof(fps->fpq)))
398				ret = -EFAULT;
399		}
400		break;
401	}
402
403	case PTRACE_SETFPREGS: {
404		ret = copy_regset_from_user(child, view, REGSET_FP,
405					    0 * sizeof(u32),
406					    32 * sizeof(u32),
407					    &fps->regs[0]);
408		if (!ret)
409			ret = copy_regset_from_user(child, view, REGSET_FP,
410						    33 * sizeof(u32),
411						    1 * sizeof(u32),
412						    &fps->fsr);
413		break;
414	}
415
416	case PTRACE_READTEXT:
417	case PTRACE_READDATA:
418		ret = ptrace_readdata(child, addr, addr2p, data);
419
420		if (ret == data)
421			ret = 0;
422		else if (ret >= 0)
423			ret = -EIO;
424		break;
425
426	case PTRACE_WRITETEXT:
427	case PTRACE_WRITEDATA:
428		ret = ptrace_writedata(child, addr2p, addr, data);
429
430		if (ret == data)
431			ret = 0;
432		else if (ret >= 0)
433			ret = -EIO;
434		break;
435
436	default:
437		if (request == PTRACE_SPARC_DETACH)
438			request = PTRACE_DETACH;
439		ret = ptrace_request(child, request, addr, data);
440		break;
441	}
442
443	return ret;
444}
445
446asmlinkage int syscall_trace(struct pt_regs *regs, int syscall_exit_p)
447{
448	int ret = 0;
449
450	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
451		if (syscall_exit_p)
452			tracehook_report_syscall_exit(regs, 0);
453		else
454			ret = tracehook_report_syscall_entry(regs);
455	}
456
457	return ret;
458}
459