xref: /openbmc/linux/arch/sparc/kernel/ptrace_32.c (revision 9cfc5c90)
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  */
38 void ptrace_disable(struct task_struct *child)
39 {
40 	/* nothing to do */
41 }
42 
43 enum sparc_regset {
44 	REGSET_GENERAL,
45 	REGSET_FP,
46 };
47 
48 static 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 	}
118 finish:
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 
126 static 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 	}
202 finish:
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 
210 static 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 
254 static 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 
286 static 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 
318 static 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 
323 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
324 {
325 	return &user_sparc32_view;
326 }
327 
328 struct 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 
340 long 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 
446 asmlinkage 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