xref: /openbmc/linux/arch/sparc/kernel/ptrace_32.c (revision 9a29f5fc)
1 // SPDX-License-Identifier: GPL-2.0
2 /* ptrace.c: Sparc process tracing support.
3  *
4  * Copyright (C) 1996, 2008 David S. Miller (davem@davemloft.net)
5  *
6  * Based upon code written by Ross Biro, Linus Torvalds, Bob Manson,
7  * and David Mosberger.
8  *
9  * Added Linux support -miguel (weird, eh?, the original code was meant
10  * to emulate SunOS).
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/sched.h>
15 #include <linux/mm.h>
16 #include <linux/errno.h>
17 #include <linux/ptrace.h>
18 #include <linux/user.h>
19 #include <linux/smp.h>
20 #include <linux/security.h>
21 #include <linux/signal.h>
22 #include <linux/regset.h>
23 #include <linux/elf.h>
24 
25 #include <linux/uaccess.h>
26 #include <asm/cacheflush.h>
27 
28 #include "kernel.h"
29 
30 /* #define ALLOW_INIT_TRACING */
31 
32 /*
33  * Called by kernel/ptrace.c when detaching..
34  *
35  * Make sure single step bits etc are not set.
36  */
37 void ptrace_disable(struct task_struct *child)
38 {
39 	/* nothing to do */
40 }
41 
42 enum sparc_regset {
43 	REGSET_GENERAL,
44 	REGSET_FP,
45 };
46 
47 static int regwindow32_get(struct task_struct *target,
48 			   const struct pt_regs *regs,
49 			   u32 *uregs)
50 {
51 	unsigned long reg_window = regs->u_regs[UREG_I6];
52 	int size = 16 * sizeof(u32);
53 
54 	if (target == current) {
55 		if (copy_from_user(uregs, (void __user *)reg_window, size))
56 			return -EFAULT;
57 	} else {
58 		if (access_process_vm(target, reg_window, uregs, size,
59 				      FOLL_FORCE) != size)
60 			return -EFAULT;
61 	}
62 	return 0;
63 }
64 
65 static int regwindow32_set(struct task_struct *target,
66 			   const struct pt_regs *regs,
67 			   u32 *uregs)
68 {
69 	unsigned long reg_window = regs->u_regs[UREG_I6];
70 	int size = 16 * sizeof(u32);
71 
72 	if (target == current) {
73 		if (copy_to_user((void __user *)reg_window, uregs, size))
74 			return -EFAULT;
75 	} else {
76 		if (access_process_vm(target, reg_window, uregs, size,
77 				      FOLL_FORCE | FOLL_WRITE) != size)
78 			return -EFAULT;
79 	}
80 	return 0;
81 }
82 
83 static int genregs32_get(struct task_struct *target,
84 			 const struct user_regset *regset,
85 			 struct membuf to)
86 {
87 	const struct pt_regs *regs = target->thread.kregs;
88 	u32 uregs[16];
89 
90 	if (target == current)
91 		flush_user_windows();
92 
93 	membuf_write(&to, regs->u_regs, 16 * sizeof(u32));
94 	if (!to.left)
95 		return 0;
96 	if (regwindow32_get(target, regs, uregs))
97 		return -EFAULT;
98 	membuf_write(&to, uregs, 16 * sizeof(u32));
99 	membuf_store(&to, regs->psr);
100 	membuf_store(&to, regs->pc);
101 	membuf_store(&to, regs->npc);
102 	membuf_store(&to, regs->y);
103 	return membuf_zero(&to, 2 * sizeof(u32));
104 }
105 
106 static int genregs32_set(struct task_struct *target,
107 			 const struct user_regset *regset,
108 			 unsigned int pos, unsigned int count,
109 			 const void *kbuf, const void __user *ubuf)
110 {
111 	struct pt_regs *regs = target->thread.kregs;
112 	u32 uregs[16];
113 	u32 psr;
114 	int ret;
115 
116 	if (target == current)
117 		flush_user_windows();
118 
119 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
120 				 regs->u_regs,
121 				 0, 16 * sizeof(u32));
122 	if (ret || !count)
123 		return ret;
124 
125 	if (regwindow32_get(target, regs, uregs))
126 		return -EFAULT;
127 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
128 				 uregs,
129 				 16 * sizeof(u32), 32 * sizeof(u32));
130 	if (ret)
131 		return ret;
132 	if (regwindow32_set(target, regs, uregs))
133 		return -EFAULT;
134 	if (!count)
135 		return 0;
136 
137 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
138 				 &psr,
139 				 32 * sizeof(u32), 33 * sizeof(u32));
140 	if (ret)
141 		return ret;
142 	regs->psr = (regs->psr & ~(PSR_ICC | PSR_SYSCALL)) |
143 		    (psr & (PSR_ICC | PSR_SYSCALL));
144 	if (!count)
145 		return 0;
146 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
147 				 &regs->pc,
148 				 33 * sizeof(u32), 34 * sizeof(u32));
149 	if (ret || !count)
150 		return ret;
151 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
152 				 &regs->npc,
153 				 34 * sizeof(u32), 35 * sizeof(u32));
154 	if (ret || !count)
155 		return ret;
156 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
157 				 &regs->y,
158 				 35 * sizeof(u32), 36 * sizeof(u32));
159 	if (ret || !count)
160 		return ret;
161 	return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
162 					 36 * sizeof(u32), 38 * sizeof(u32));
163 }
164 
165 static int fpregs32_get(struct task_struct *target,
166 			const struct user_regset *regset,
167 			struct membuf to)
168 {
169 #if 0
170 	if (target == current)
171 		save_and_clear_fpu();
172 #endif
173 
174 	membuf_write(&to, target->thread.float_regs, 32 * sizeof(u32));
175 	membuf_zero(&to, sizeof(u32));
176 	membuf_write(&to, &target->thread.fsr, sizeof(u32));
177 	membuf_store(&to, (u32)((1 << 8) | (8 << 16)));
178 	return membuf_zero(&to, 64 * sizeof(u32));
179 }
180 
181 static int fpregs32_set(struct task_struct *target,
182 			const struct user_regset *regset,
183 			unsigned int pos, unsigned int count,
184 			const void *kbuf, const void __user *ubuf)
185 {
186 	unsigned long *fpregs = target->thread.float_regs;
187 	int ret;
188 
189 #if 0
190 	if (target == current)
191 		save_and_clear_fpu();
192 #endif
193 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
194 				 fpregs,
195 				 0, 32 * sizeof(u32));
196 	if (!ret)
197 		user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
198 					  32 * sizeof(u32),
199 					  33 * sizeof(u32));
200 	if (!ret)
201 		ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
202 					 &target->thread.fsr,
203 					 33 * sizeof(u32),
204 					 34 * sizeof(u32));
205 	if (!ret)
206 		ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
207 						34 * sizeof(u32), -1);
208 	return ret;
209 }
210 
211 static const struct user_regset sparc32_regsets[] = {
212 	/* Format is:
213 	 * 	G0 --> G7
214 	 *	O0 --> O7
215 	 *	L0 --> L7
216 	 *	I0 --> I7
217 	 *	PSR, PC, nPC, Y, WIM, TBR
218 	 */
219 	[REGSET_GENERAL] = {
220 		.core_note_type = NT_PRSTATUS,
221 		.n = 38,
222 		.size = sizeof(u32), .align = sizeof(u32),
223 		.regset_get = genregs32_get, .set = genregs32_set
224 	},
225 	/* Format is:
226 	 *	F0 --> F31
227 	 *	empty 32-bit word
228 	 *	FSR (32--bit word)
229 	 *	FPU QUEUE COUNT (8-bit char)
230 	 *	FPU QUEUE ENTRYSIZE (8-bit char)
231 	 *	FPU ENABLED (8-bit char)
232 	 *	empty 8-bit char
233 	 *	FPU QUEUE (64 32-bit ints)
234 	 */
235 	[REGSET_FP] = {
236 		.core_note_type = NT_PRFPREG,
237 		.n = 99,
238 		.size = sizeof(u32), .align = sizeof(u32),
239 		.regset_get = fpregs32_get, .set = fpregs32_set
240 	},
241 };
242 
243 static int getregs_get(struct task_struct *target,
244 			 const struct user_regset *regset,
245 			 struct membuf to)
246 {
247 	const struct pt_regs *regs = target->thread.kregs;
248 
249 	if (target == current)
250 		flush_user_windows();
251 
252 	membuf_store(&to, regs->psr);
253 	membuf_store(&to, regs->pc);
254 	membuf_store(&to, regs->npc);
255 	membuf_store(&to, regs->y);
256 	return membuf_write(&to, regs->u_regs + 1, 15 * sizeof(u32));
257 }
258 
259 static int setregs_set(struct task_struct *target,
260 			 const struct user_regset *regset,
261 			 unsigned int pos, unsigned int count,
262 			 const void *kbuf, const void __user *ubuf)
263 {
264 	struct pt_regs *regs = target->thread.kregs;
265 	u32 v[4];
266 	int ret;
267 
268 	if (target == current)
269 		flush_user_windows();
270 
271 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
272 				 v,
273 				 0, 4 * sizeof(u32));
274 	if (ret)
275 		return ret;
276 	regs->psr = (regs->psr & ~(PSR_ICC | PSR_SYSCALL)) |
277 		    (v[0] & (PSR_ICC | PSR_SYSCALL));
278 	regs->pc = v[1];
279 	regs->npc = v[2];
280 	regs->y = v[3];
281 	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
282 				 regs->u_regs + 1,
283 				 4 * sizeof(u32) , 19 * sizeof(u32));
284 }
285 
286 static int getfpregs_get(struct task_struct *target,
287 			const struct user_regset *regset,
288 			struct membuf to)
289 {
290 #if 0
291 	if (target == current)
292 		save_and_clear_fpu();
293 #endif
294 	membuf_write(&to, &target->thread.float_regs, 32 * sizeof(u32));
295 	membuf_write(&to, &target->thread.fsr, sizeof(u32));
296 	return membuf_zero(&to, 35 * sizeof(u32));
297 }
298 
299 static int setfpregs_set(struct task_struct *target,
300 			const struct user_regset *regset,
301 			unsigned int pos, unsigned int count,
302 			const void *kbuf, const void __user *ubuf)
303 {
304 	unsigned long *fpregs = target->thread.float_regs;
305 	int ret;
306 
307 #if 0
308 	if (target == current)
309 		save_and_clear_fpu();
310 #endif
311 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
312 				 fpregs,
313 				 0, 32 * sizeof(u32));
314 	if (ret)
315 		return ret;
316 	return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
317 				 &target->thread.fsr,
318 				 32 * sizeof(u32),
319 				 33 * sizeof(u32));
320 }
321 
322 static const struct user_regset ptrace32_regsets[] = {
323 	[REGSET_GENERAL] = {
324 		.n = 19, .size = sizeof(u32),
325 		.regset_get = getregs_get, .set = setregs_set,
326 	},
327 	[REGSET_FP] = {
328 		.n = 68, .size = sizeof(u32),
329 		.regset_get = getfpregs_get, .set = setfpregs_set,
330 	},
331 };
332 
333 static const struct user_regset_view ptrace32_view = {
334 	.regsets = ptrace32_regsets, .n = ARRAY_SIZE(ptrace32_regsets)
335 };
336 
337 static const struct user_regset_view user_sparc32_view = {
338 	.name = "sparc", .e_machine = EM_SPARC,
339 	.regsets = sparc32_regsets, .n = ARRAY_SIZE(sparc32_regsets)
340 };
341 
342 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
343 {
344 	return &user_sparc32_view;
345 }
346 
347 struct fps {
348 	unsigned long regs[32];
349 	unsigned long fsr;
350 	unsigned long flags;
351 	unsigned long extra;
352 	unsigned long fpqd;
353 	struct fq {
354 		unsigned long *insnaddr;
355 		unsigned long insn;
356 	} fpq[16];
357 };
358 
359 long arch_ptrace(struct task_struct *child, long request,
360 		 unsigned long addr, unsigned long data)
361 {
362 	unsigned long addr2 = current->thread.kregs->u_regs[UREG_I4];
363 	void __user *addr2p;
364 	struct pt_regs __user *pregs;
365 	struct fps __user *fps;
366 	int ret;
367 
368 	addr2p = (void __user *) addr2;
369 	pregs = (struct pt_regs __user *) addr;
370 	fps = (struct fps __user *) addr;
371 
372 	switch(request) {
373 	case PTRACE_GETREGS: {
374 		ret = copy_regset_to_user(child, &ptrace32_view,
375 					  REGSET_GENERAL, 0,
376 					  19 * sizeof(u32),
377 					  pregs);
378 		break;
379 	}
380 
381 	case PTRACE_SETREGS: {
382 		ret = copy_regset_from_user(child, &ptrace32_view,
383 					    REGSET_GENERAL, 0,
384 					    19 * sizeof(u32),
385 					    pregs);
386 		break;
387 	}
388 
389 	case PTRACE_GETFPREGS: {
390 		ret = copy_regset_to_user(child, &ptrace32_view,
391 					  REGSET_FP, 0,
392 					  68 * sizeof(u32),
393 					  fps);
394 		break;
395 	}
396 
397 	case PTRACE_SETFPREGS: {
398 		ret = copy_regset_from_user(child, &ptrace32_view,
399 					  REGSET_FP, 0,
400 					  33 * sizeof(u32),
401 					  fps);
402 		break;
403 	}
404 
405 	case PTRACE_READTEXT:
406 	case PTRACE_READDATA:
407 		ret = ptrace_readdata(child, addr, addr2p, data);
408 
409 		if (ret == data)
410 			ret = 0;
411 		else if (ret >= 0)
412 			ret = -EIO;
413 		break;
414 
415 	case PTRACE_WRITETEXT:
416 	case PTRACE_WRITEDATA:
417 		ret = ptrace_writedata(child, addr2p, addr, data);
418 
419 		if (ret == data)
420 			ret = 0;
421 		else if (ret >= 0)
422 			ret = -EIO;
423 		break;
424 
425 	default:
426 		if (request == PTRACE_SPARC_DETACH)
427 			request = PTRACE_DETACH;
428 		ret = ptrace_request(child, request, addr, data);
429 		break;
430 	}
431 
432 	return ret;
433 }
434 
435 asmlinkage int syscall_trace(struct pt_regs *regs, int syscall_exit_p)
436 {
437 	int ret = 0;
438 
439 	if (test_thread_flag(TIF_SYSCALL_TRACE)) {
440 		if (syscall_exit_p)
441 			ptrace_report_syscall_exit(regs, 0);
442 		else
443 			ret = ptrace_report_syscall_entry(regs);
444 	}
445 
446 	return ret;
447 }
448