xref: /openbmc/linux/arch/sparc/kernel/ptrace_32.c (revision 63dc02bd)
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 /* #define ALLOW_INIT_TRACING */
30 
31 /*
32  * Called by kernel/ptrace.c when detaching..
33  *
34  * Make sure single step bits etc are not set.
35  */
36 void ptrace_disable(struct task_struct *child)
37 {
38 	/* nothing to do */
39 }
40 
41 enum sparc_regset {
42 	REGSET_GENERAL,
43 	REGSET_FP,
44 };
45 
46 static int genregs32_get(struct task_struct *target,
47 			 const struct user_regset *regset,
48 			 unsigned int pos, unsigned int count,
49 			 void *kbuf, void __user *ubuf)
50 {
51 	const struct pt_regs *regs = target->thread.kregs;
52 	unsigned long __user *reg_window;
53 	unsigned long *k = kbuf;
54 	unsigned long __user *u = ubuf;
55 	unsigned long reg;
56 
57 	if (target == current)
58 		flush_user_windows();
59 
60 	pos /= sizeof(reg);
61 	count /= sizeof(reg);
62 
63 	if (kbuf) {
64 		for (; count > 0 && pos < 16; count--)
65 			*k++ = regs->u_regs[pos++];
66 
67 		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
68 		reg_window -= 16;
69 		for (; count > 0 && pos < 32; count--) {
70 			if (get_user(*k++, &reg_window[pos++]))
71 				return -EFAULT;
72 		}
73 	} else {
74 		for (; count > 0 && pos < 16; count--) {
75 			if (put_user(regs->u_regs[pos++], u++))
76 				return -EFAULT;
77 		}
78 
79 		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
80 		reg_window -= 16;
81 		for (; count > 0 && pos < 32; count--) {
82 			if (get_user(reg, &reg_window[pos++]) ||
83 			    put_user(reg, u++))
84 				return -EFAULT;
85 		}
86 	}
87 	while (count > 0) {
88 		switch (pos) {
89 		case 32: /* PSR */
90 			reg = regs->psr;
91 			break;
92 		case 33: /* PC */
93 			reg = regs->pc;
94 			break;
95 		case 34: /* NPC */
96 			reg = regs->npc;
97 			break;
98 		case 35: /* Y */
99 			reg = regs->y;
100 			break;
101 		case 36: /* WIM */
102 		case 37: /* TBR */
103 			reg = 0;
104 			break;
105 		default:
106 			goto finish;
107 		}
108 
109 		if (kbuf)
110 			*k++ = reg;
111 		else if (put_user(reg, u++))
112 			return -EFAULT;
113 		pos++;
114 		count--;
115 	}
116 finish:
117 	pos *= sizeof(reg);
118 	count *= sizeof(reg);
119 
120 	return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
121 					38 * sizeof(reg), -1);
122 }
123 
124 static int genregs32_set(struct task_struct *target,
125 			 const struct user_regset *regset,
126 			 unsigned int pos, unsigned int count,
127 			 const void *kbuf, const void __user *ubuf)
128 {
129 	struct pt_regs *regs = target->thread.kregs;
130 	unsigned long __user *reg_window;
131 	const unsigned long *k = kbuf;
132 	const unsigned long __user *u = ubuf;
133 	unsigned long reg;
134 
135 	if (target == current)
136 		flush_user_windows();
137 
138 	pos /= sizeof(reg);
139 	count /= sizeof(reg);
140 
141 	if (kbuf) {
142 		for (; count > 0 && pos < 16; count--)
143 			regs->u_regs[pos++] = *k++;
144 
145 		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
146 		reg_window -= 16;
147 		for (; count > 0 && pos < 32; count--) {
148 			if (put_user(*k++, &reg_window[pos++]))
149 				return -EFAULT;
150 		}
151 	} else {
152 		for (; count > 0 && pos < 16; count--) {
153 			if (get_user(reg, u++))
154 				return -EFAULT;
155 			regs->u_regs[pos++] = reg;
156 		}
157 
158 		reg_window = (unsigned long __user *) regs->u_regs[UREG_I6];
159 		reg_window -= 16;
160 		for (; count > 0 && pos < 32; count--) {
161 			if (get_user(reg, u++) ||
162 			    put_user(reg, &reg_window[pos++]))
163 				return -EFAULT;
164 		}
165 	}
166 	while (count > 0) {
167 		unsigned long psr;
168 
169 		if (kbuf)
170 			reg = *k++;
171 		else if (get_user(reg, u++))
172 			return -EFAULT;
173 
174 		switch (pos) {
175 		case 32: /* PSR */
176 			psr = regs->psr;
177 			psr &= ~(PSR_ICC | PSR_SYSCALL);
178 			psr |= (reg & (PSR_ICC | PSR_SYSCALL));
179 			regs->psr = psr;
180 			break;
181 		case 33: /* PC */
182 			regs->pc = reg;
183 			break;
184 		case 34: /* NPC */
185 			regs->npc = reg;
186 			break;
187 		case 35: /* Y */
188 			regs->y = reg;
189 			break;
190 		case 36: /* WIM */
191 		case 37: /* TBR */
192 			break;
193 		default:
194 			goto finish;
195 		}
196 
197 		pos++;
198 		count--;
199 	}
200 finish:
201 	pos *= sizeof(reg);
202 	count *= sizeof(reg);
203 
204 	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
205 					 38 * sizeof(reg), -1);
206 }
207 
208 static int fpregs32_get(struct task_struct *target,
209 			const struct user_regset *regset,
210 			unsigned int pos, unsigned int count,
211 			void *kbuf, void __user *ubuf)
212 {
213 	const unsigned long *fpregs = target->thread.float_regs;
214 	int ret = 0;
215 
216 #if 0
217 	if (target == current)
218 		save_and_clear_fpu();
219 #endif
220 
221 	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
222 				  fpregs,
223 				  0, 32 * sizeof(u32));
224 
225 	if (!ret)
226 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
227 					       32 * sizeof(u32),
228 					       33 * sizeof(u32));
229 	if (!ret)
230 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
231 					  &target->thread.fsr,
232 					  33 * sizeof(u32),
233 					  34 * sizeof(u32));
234 
235 	if (!ret) {
236 		unsigned long val;
237 
238 		val = (1 << 8) | (8 << 16);
239 		ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
240 					  &val,
241 					  34 * sizeof(u32),
242 					  35 * sizeof(u32));
243 	}
244 
245 	if (!ret)
246 		ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
247 					       35 * sizeof(u32), -1);
248 
249 	return ret;
250 }
251 
252 static int fpregs32_set(struct task_struct *target,
253 			const struct user_regset *regset,
254 			unsigned int pos, unsigned int count,
255 			const void *kbuf, const void __user *ubuf)
256 {
257 	unsigned long *fpregs = target->thread.float_regs;
258 	int ret;
259 
260 #if 0
261 	if (target == current)
262 		save_and_clear_fpu();
263 #endif
264 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
265 				 fpregs,
266 				 0, 32 * sizeof(u32));
267 	if (!ret)
268 		user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
269 					  32 * sizeof(u32),
270 					  33 * sizeof(u32));
271 	if (!ret && count > 0) {
272 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
273 					 &target->thread.fsr,
274 					 33 * sizeof(u32),
275 					 34 * sizeof(u32));
276 	}
277 
278 	if (!ret)
279 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
280 						34 * sizeof(u32), -1);
281 	return ret;
282 }
283 
284 static const struct user_regset sparc32_regsets[] = {
285 	/* Format is:
286 	 * 	G0 --> G7
287 	 *	O0 --> O7
288 	 *	L0 --> L7
289 	 *	I0 --> I7
290 	 *	PSR, PC, nPC, Y, WIM, TBR
291 	 */
292 	[REGSET_GENERAL] = {
293 		.core_note_type = NT_PRSTATUS,
294 		.n = 38,
295 		.size = sizeof(u32), .align = sizeof(u32),
296 		.get = genregs32_get, .set = genregs32_set
297 	},
298 	/* Format is:
299 	 *	F0 --> F31
300 	 *	empty 32-bit word
301 	 *	FSR (32--bit word)
302 	 *	FPU QUEUE COUNT (8-bit char)
303 	 *	FPU QUEUE ENTRYSIZE (8-bit char)
304 	 *	FPU ENABLED (8-bit char)
305 	 *	empty 8-bit char
306 	 *	FPU QUEUE (64 32-bit ints)
307 	 */
308 	[REGSET_FP] = {
309 		.core_note_type = NT_PRFPREG,
310 		.n = 99,
311 		.size = sizeof(u32), .align = sizeof(u32),
312 		.get = fpregs32_get, .set = fpregs32_set
313 	},
314 };
315 
316 static const struct user_regset_view user_sparc32_view = {
317 	.name = "sparc", .e_machine = EM_SPARC,
318 	.regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
319 };
320 
321 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
322 {
323 	return &user_sparc32_view;
324 }
325 
326 struct fps {
327 	unsigned long regs[32];
328 	unsigned long fsr;
329 	unsigned long flags;
330 	unsigned long extra;
331 	unsigned long fpqd;
332 	struct fq {
333 		unsigned long *insnaddr;
334 		unsigned long insn;
335 	} fpq[16];
336 };
337 
338 long arch_ptrace(struct task_struct *child, long request,
339 		 unsigned long addr, unsigned long data)
340 {
341 	unsigned long addr2 = current->thread.kregs->u_regs[UREG_I4];
342 	void __user *addr2p;
343 	const struct user_regset_view *view;
344 	struct pt_regs __user *pregs;
345 	struct fps __user *fps;
346 	int ret;
347 
348 	view = task_user_regset_view(current);
349 	addr2p = (void __user *) addr2;
350 	pregs = (struct pt_regs __user *) addr;
351 	fps = (struct fps __user *) addr;
352 
353 	switch(request) {
354 	case PTRACE_GETREGS: {
355 		ret = copy_regset_to_user(child, view, REGSET_GENERAL,
356 					  32 * sizeof(u32),
357 					  4 * sizeof(u32),
358 					  &pregs->psr);
359 		if (!ret)
360 			copy_regset_to_user(child, view, REGSET_GENERAL,
361 					    1 * sizeof(u32),
362 					    15 * sizeof(u32),
363 					    &pregs->u_regs[0]);
364 		break;
365 	}
366 
367 	case PTRACE_SETREGS: {
368 		ret = copy_regset_from_user(child, view, REGSET_GENERAL,
369 					    32 * sizeof(u32),
370 					    4 * sizeof(u32),
371 					    &pregs->psr);
372 		if (!ret)
373 			copy_regset_from_user(child, view, REGSET_GENERAL,
374 					      1 * sizeof(u32),
375 					      15 * sizeof(u32),
376 					      &pregs->u_regs[0]);
377 		break;
378 	}
379 
380 	case PTRACE_GETFPREGS: {
381 		ret = copy_regset_to_user(child, view, REGSET_FP,
382 					  0 * sizeof(u32),
383 					  32 * sizeof(u32),
384 					  &fps->regs[0]);
385 		if (!ret)
386 			ret = copy_regset_to_user(child, view, REGSET_FP,
387 						  33 * sizeof(u32),
388 						  1 * sizeof(u32),
389 						  &fps->fsr);
390 
391 		if (!ret) {
392 			if (__put_user(0, &fps->fpqd) ||
393 			    __put_user(0, &fps->flags) ||
394 			    __put_user(0, &fps->extra) ||
395 			    clear_user(fps->fpq, sizeof(fps->fpq)))
396 				ret = -EFAULT;
397 		}
398 		break;
399 	}
400 
401 	case PTRACE_SETFPREGS: {
402 		ret = copy_regset_from_user(child, view, REGSET_FP,
403 					    0 * sizeof(u32),
404 					    32 * sizeof(u32),
405 					    &fps->regs[0]);
406 		if (!ret)
407 			ret = copy_regset_from_user(child, view, REGSET_FP,
408 						    33 * sizeof(u32),
409 						    1 * sizeof(u32),
410 						    &fps->fsr);
411 		break;
412 	}
413 
414 	case PTRACE_READTEXT:
415 	case PTRACE_READDATA:
416 		ret = ptrace_readdata(child, addr, addr2p, data);
417 
418 		if (ret == data)
419 			ret = 0;
420 		else if (ret >= 0)
421 			ret = -EIO;
422 		break;
423 
424 	case PTRACE_WRITETEXT:
425 	case PTRACE_WRITEDATA:
426 		ret = ptrace_writedata(child, addr2p, addr, data);
427 
428 		if (ret == data)
429 			ret = 0;
430 		else if (ret >= 0)
431 			ret = -EIO;
432 		break;
433 
434 	default:
435 		if (request == PTRACE_SPARC_DETACH)
436 			request = PTRACE_DETACH;
437 		ret = ptrace_request(child, request, addr, data);
438 		break;
439 	}
440 
441 	return ret;
442 }
443 
444 asmlinkage int syscall_trace(struct pt_regs *regs, int syscall_exit_p)
445 {
446 	int ret = 0;
447 
448 	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
449 		if (syscall_exit_p)
450 			tracehook_report_syscall_exit(regs, 0);
451 		else
452 			ret = tracehook_report_syscall_entry(regs);
453 	}
454 
455 	return ret;
456 }
457