More .set to keep 32-bit processors happy.
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / mips / kernel / ptrace.c
CommitLineData
1da177e4
LT
1/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Copyright (C) 1992 Ross Biro
7 * Copyright (C) Linus Torvalds
8 * Copyright (C) 1994, 95, 96, 97, 98, 2000 Ralf Baechle
9 * Copyright (C) 1996 David S. Miller
10 * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
11 * Copyright (C) 1999 MIPS Technologies, Inc.
12 * Copyright (C) 2000 Ulf Carlsson
13 *
14 * At this time Linux/MIPS64 only supports syscall tracing, even for 32-bit
15 * binaries.
16 */
17#include <linux/config.h>
18#include <linux/compiler.h>
19#include <linux/kernel.h>
20#include <linux/sched.h>
21#include <linux/mm.h>
22#include <linux/errno.h>
23#include <linux/ptrace.h>
24#include <linux/audit.h>
25#include <linux/smp.h>
26#include <linux/smp_lock.h>
27#include <linux/user.h>
28#include <linux/security.h>
7ed20e1a 29#include <linux/signal.h>
1da177e4 30
f8280c8d 31#include <asm/byteorder.h>
1da177e4 32#include <asm/cpu.h>
e50c0a8f 33#include <asm/dsp.h>
1da177e4
LT
34#include <asm/fpu.h>
35#include <asm/mipsregs.h>
36#include <asm/pgtable.h>
37#include <asm/page.h>
38#include <asm/system.h>
39#include <asm/uaccess.h>
40#include <asm/bootinfo.h>
41
42/*
43 * Called by kernel/ptrace.c when detaching..
44 *
45 * Make sure single step bits etc are not set.
46 */
47void ptrace_disable(struct task_struct *child)
48{
49 /* Nothing to do.. */
50}
51
52asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
53{
54 struct task_struct *child;
55 int ret;
56
57#if 0
58 printk("ptrace(r=%d,pid=%d,addr=%08lx,data=%08lx)\n",
59 (int) request, (int) pid, (unsigned long) addr,
60 (unsigned long) data);
61#endif
62 lock_kernel();
63 ret = -EPERM;
64 if (request == PTRACE_TRACEME) {
65 /* are we already being traced? */
66 if (current->ptrace & PT_PTRACED)
67 goto out;
68 if ((ret = security_ptrace(current->parent, current)))
69 goto out;
70 /* set the ptrace bit in the process flags. */
71 current->ptrace |= PT_PTRACED;
72 ret = 0;
73 goto out;
74 }
75 ret = -ESRCH;
76 read_lock(&tasklist_lock);
77 child = find_task_by_pid(pid);
78 if (child)
79 get_task_struct(child);
80 read_unlock(&tasklist_lock);
81 if (!child)
82 goto out;
83
84 ret = -EPERM;
85 if (pid == 1) /* you may not mess with init */
86 goto out_tsk;
87
88 if (request == PTRACE_ATTACH) {
89 ret = ptrace_attach(child);
90 goto out_tsk;
91 }
92
93 ret = ptrace_check_attach(child, request == PTRACE_KILL);
94 if (ret < 0)
95 goto out_tsk;
96
97 switch (request) {
98 /* when I and D space are separate, these will need to be fixed. */
99 case PTRACE_PEEKTEXT: /* read word at location addr. */
100 case PTRACE_PEEKDATA: {
101 unsigned long tmp;
102 int copied;
103
104 copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
105 ret = -EIO;
106 if (copied != sizeof(tmp))
107 break;
fe00f943 108 ret = put_user(tmp,(unsigned long __user *) data);
1da177e4
LT
109 break;
110 }
111
112 /* Read the word at location addr in the USER area. */
113 case PTRACE_PEEKUSR: {
114 struct pt_regs *regs;
115 unsigned long tmp = 0;
116
117 regs = (struct pt_regs *) ((unsigned long) child->thread_info +
118 THREAD_SIZE - 32 - sizeof(struct pt_regs));
119 ret = 0; /* Default return value. */
120
121 switch (addr) {
122 case 0 ... 31:
123 tmp = regs->regs[addr];
124 break;
125 case FPR_BASE ... FPR_BASE + 31:
126 if (tsk_used_math(child)) {
127 fpureg_t *fregs = get_fpu_regs(child);
128
875d43e7 129#ifdef CONFIG_32BIT
1da177e4
LT
130 /*
131 * The odd registers are actually the high
132 * order bits of the values stored in the even
133 * registers - unless we're using r2k_switch.S.
134 */
135 if (addr & 1)
136 tmp = (unsigned long) (fregs[((addr & ~1) - 32)] >> 32);
137 else
138 tmp = (unsigned long) (fregs[(addr - 32)] & 0xffffffff);
139#endif
875d43e7 140#ifdef CONFIG_64BIT
1da177e4
LT
141 tmp = fregs[addr - FPR_BASE];
142#endif
143 } else {
144 tmp = -1; /* FP not yet used */
145 }
146 break;
147 case PC:
148 tmp = regs->cp0_epc;
149 break;
150 case CAUSE:
151 tmp = regs->cp0_cause;
152 break;
153 case BADVADDR:
154 tmp = regs->cp0_badvaddr;
155 break;
156 case MMHI:
157 tmp = regs->hi;
158 break;
159 case MMLO:
160 tmp = regs->lo;
161 break;
162 case FPC_CSR:
163 if (cpu_has_fpu)
164 tmp = child->thread.fpu.hard.fcr31;
165 else
166 tmp = child->thread.fpu.soft.fcr31;
167 break;
168 case FPC_EIR: { /* implementation / version register */
169 unsigned int flags;
170
171 if (!cpu_has_fpu)
172 break;
173
174 flags = read_c0_status();
175 __enable_fpu();
176 __asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
177 write_c0_status(flags);
178 break;
179 }
e50c0a8f
RB
180 case DSP_BASE ... DSP_BASE + 5:
181 if (!cpu_has_dsp) {
182 tmp = 0;
183 ret = -EIO;
184 goto out_tsk;
185 }
186 if (child->thread.dsp.used_dsp) {
187 dspreg_t *dregs = __get_dsp_regs(child);
188 tmp = (unsigned long) (dregs[addr - DSP_BASE]);
189 } else {
190 tmp = -1; /* DSP registers yet used */
191 }
192 break;
193 case DSP_CONTROL:
194 if (!cpu_has_dsp) {
195 tmp = 0;
196 ret = -EIO;
197 goto out_tsk;
198 }
199 tmp = child->thread.dsp.dspcontrol;
200 break;
1da177e4
LT
201 default:
202 tmp = 0;
203 ret = -EIO;
204 goto out_tsk;
205 }
fe00f943 206 ret = put_user(tmp, (unsigned long __user *) data);
1da177e4
LT
207 break;
208 }
209
210 /* when I and D space are separate, this will have to be fixed. */
211 case PTRACE_POKETEXT: /* write the word at location addr. */
212 case PTRACE_POKEDATA:
213 ret = 0;
214 if (access_process_vm(child, addr, &data, sizeof(data), 1)
215 == sizeof(data))
216 break;
217 ret = -EIO;
218 break;
219
220 case PTRACE_POKEUSR: {
221 struct pt_regs *regs;
222 ret = 0;
223 regs = (struct pt_regs *) ((unsigned long) child->thread_info +
224 THREAD_SIZE - 32 - sizeof(struct pt_regs));
225
226 switch (addr) {
227 case 0 ... 31:
228 regs->regs[addr] = data;
229 break;
230 case FPR_BASE ... FPR_BASE + 31: {
231 fpureg_t *fregs = get_fpu_regs(child);
232
233 if (!tsk_used_math(child)) {
234 /* FP not yet used */
235 memset(&child->thread.fpu.hard, ~0,
236 sizeof(child->thread.fpu.hard));
237 child->thread.fpu.hard.fcr31 = 0;
238 }
875d43e7 239#ifdef CONFIG_32BIT
1da177e4
LT
240 /*
241 * The odd registers are actually the high order bits
242 * of the values stored in the even registers - unless
243 * we're using r2k_switch.S.
244 */
245 if (addr & 1) {
246 fregs[(addr & ~1) - FPR_BASE] &= 0xffffffff;
247 fregs[(addr & ~1) - FPR_BASE] |= ((unsigned long long) data) << 32;
248 } else {
249 fregs[addr - FPR_BASE] &= ~0xffffffffLL;
250 fregs[addr - FPR_BASE] |= data;
251 }
252#endif
875d43e7 253#ifdef CONFIG_64BIT
1da177e4
LT
254 fregs[addr - FPR_BASE] = data;
255#endif
256 break;
257 }
258 case PC:
259 regs->cp0_epc = data;
260 break;
261 case MMHI:
262 regs->hi = data;
263 break;
264 case MMLO:
265 regs->lo = data;
266 break;
267 case FPC_CSR:
268 if (cpu_has_fpu)
269 child->thread.fpu.hard.fcr31 = data;
270 else
271 child->thread.fpu.soft.fcr31 = data;
272 break;
e50c0a8f
RB
273 case DSP_BASE ... DSP_BASE + 5:
274 if (!cpu_has_dsp) {
275 ret = -EIO;
276 break;
277 }
278
279 dspreg_t *dregs = __get_dsp_regs(child);
280 dregs[addr - DSP_BASE] = data;
281 break;
282 case DSP_CONTROL:
283 if (!cpu_has_dsp) {
284 ret = -EIO;
285 break;
286 }
287 child->thread.dsp.dspcontrol = data;
288 break;
1da177e4
LT
289 default:
290 /* The rest are not allowed. */
291 ret = -EIO;
292 break;
293 }
294 break;
295 }
296
297 case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
298 case PTRACE_CONT: { /* restart after signal. */
299 ret = -EIO;
7ed20e1a 300 if (!valid_signal(data))
1da177e4
LT
301 break;
302 if (request == PTRACE_SYSCALL) {
303 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
304 }
305 else {
306 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
307 }
308 child->exit_code = data;
309 wake_up_process(child);
310 ret = 0;
311 break;
312 }
313
314 /*
315 * make the child exit. Best I can do is send it a sigkill.
316 * perhaps it should be put in the status that it wants to
317 * exit.
318 */
319 case PTRACE_KILL:
320 ret = 0;
321 if (child->exit_state == EXIT_ZOMBIE) /* already dead */
322 break;
323 child->exit_code = SIGKILL;
324 wake_up_process(child);
325 break;
326
327 case PTRACE_DETACH: /* detach a process that was attached. */
328 ret = ptrace_detach(child, data);
329 break;
330
3c37026d
RB
331 case PTRACE_GET_THREAD_AREA:
332 ret = put_user(child->thread_info->tp_value,
333 (unsigned long __user *) data);
334 break;
335
1da177e4
LT
336 default:
337 ret = ptrace_request(child, request, addr, data);
338 break;
339 }
340
341out_tsk:
342 put_task_struct(child);
343out:
344 unlock_kernel();
345 return ret;
346}
347
67eb81e1 348static inline int audit_arch(void)
2fd6f58b 349{
f8280c8d 350 int arch = EM_MIPS;
875d43e7 351#ifdef CONFIG_64BIT
f8280c8d
RB
352 arch |= __AUDIT_ARCH_64BIT;
353#endif
354#if defined(__LITTLE_ENDIAN)
355 arch |= __AUDIT_ARCH_LE;
356#endif
357 return arch;
2fd6f58b
DW
358}
359
1da177e4
LT
360/*
361 * Notification of system call entry/exit
362 * - triggered by current->work.syscall_trace
363 */
364asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit)
365{
2fd6f58b 366 if (unlikely(current->audit_context) && entryexit)
f8280c8d
RB
367 audit_syscall_exit(current, AUDITSC_RESULT(regs->regs[2]),
368 regs->regs[2]);
1da177e4 369
1da177e4 370 if (!(current->ptrace & PT_PTRACED))
2fd6f58b 371 goto out;
f8280c8d
RB
372 if (!test_thread_flag(TIF_SYSCALL_TRACE))
373 goto out;
1da177e4
LT
374
375 /* The 0x80 provides a way for the tracing parent to distinguish
376 between a syscall stop and SIGTRAP delivery */
377 ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) ?
378 0x80 : 0));
379
380 /*
381 * this isn't the same as continuing with a signal, but it will do
382 * for normal use. strace only continues with a signal if the
383 * stopping signal is not SIGTRAP. -brl
384 */
385 if (current->exit_code) {
386 send_sig(current->exit_code, current, 1);
387 current->exit_code = 0;
388 }
2fd6f58b
DW
389 out:
390 if (unlikely(current->audit_context) && !entryexit)
391 audit_syscall_entry(current, audit_arch(), regs->regs[2],
392 regs->regs[4], regs->regs[5],
393 regs->regs[6], regs->regs[7]);
1da177e4 394}