[PATCH] use ptrace_get_task_struct in various places
[linux-2.6.git] / arch / mips / kernel / ptrace32.c
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/compiler.h>
18 #include <linux/kernel.h>
19 #include <linux/sched.h>
20 #include <linux/mm.h>
21 #include <linux/errno.h>
22 #include <linux/ptrace.h>
23 #include <linux/smp.h>
24 #include <linux/smp_lock.h>
25 #include <linux/user.h>
26 #include <linux/security.h>
27
28 #include <asm/cpu.h>
29 #include <asm/dsp.h>
30 #include <asm/fpu.h>
31 #include <asm/mipsregs.h>
32 #include <asm/mipsmtregs.h>
33 #include <asm/pgtable.h>
34 #include <asm/page.h>
35 #include <asm/system.h>
36 #include <asm/uaccess.h>
37 #include <asm/bootinfo.h>
38
39 int ptrace_getregs (struct task_struct *child, __s64 __user *data);
40 int ptrace_setregs (struct task_struct *child, __s64 __user *data);
41
42 int ptrace_getfpregs (struct task_struct *child, __u32 __user *data);
43 int ptrace_setfpregs (struct task_struct *child, __u32 __user *data);
44
45 /*
46  * Tracing a 32-bit process with a 64-bit strace and vice versa will not
47  * work.  I don't know how to fix this.
48  */
49 asmlinkage int sys32_ptrace(int request, int pid, int addr, int data)
50 {
51         struct task_struct *child;
52         int ret;
53
54 #if 0
55         printk("ptrace(r=%d,pid=%d,addr=%08lx,data=%08lx)\n",
56                (int) request, (int) pid, (unsigned long) addr,
57                (unsigned long) data);
58 #endif
59         lock_kernel();
60         if (request == PTRACE_TRACEME) {
61                 ret = ptrace_traceme();
62                 goto out;
63         }
64
65         child = ptrace_get_task_struct(pid);
66         if (IS_ERR(child)) {
67                 ret = PTR_ERR(child);
68                 goto out;
69         }
70
71         if (request == PTRACE_ATTACH) {
72                 ret = ptrace_attach(child);
73                 goto out_tsk;
74         }
75
76         ret = ptrace_check_attach(child, request == PTRACE_KILL);
77         if (ret < 0)
78                 goto out_tsk;
79
80         switch (request) {
81         /* when I and D space are separate, these will need to be fixed. */
82         case PTRACE_PEEKTEXT: /* read word at location addr. */
83         case PTRACE_PEEKDATA: {
84                 unsigned int tmp;
85                 int copied;
86
87                 copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
88                 ret = -EIO;
89                 if (copied != sizeof(tmp))
90                         break;
91                 ret = put_user(tmp, (unsigned int *) (unsigned long) data);
92                 break;
93         }
94
95         /*
96          * Read 4 bytes of the other process' storage
97          *  data is a pointer specifying where the user wants the
98          *      4 bytes copied into
99          *  addr is a pointer in the user's storage that contains an 8 byte
100          *      address in the other process of the 4 bytes that is to be read
101          * (this is run in a 32-bit process looking at a 64-bit process)
102          * when I and D space are separate, these will need to be fixed.
103          */
104         case PTRACE_PEEKTEXT_3264:
105         case PTRACE_PEEKDATA_3264: {
106                 u32 tmp;
107                 int copied;
108                 u32 __user * addrOthers;
109
110                 ret = -EIO;
111
112                 /* Get the addr in the other process that we want to read */
113                 if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)
114                         break;
115
116                 copied = access_process_vm(child, (u64)addrOthers, &tmp,
117                                 sizeof(tmp), 0);
118                 if (copied != sizeof(tmp))
119                         break;
120                 ret = put_user(tmp, (u32 __user *) (unsigned long) data);
121                 break;
122         }
123
124         /* Read the word at location addr in the USER area. */
125         case PTRACE_PEEKUSR: {
126                 struct pt_regs *regs;
127                 unsigned int tmp;
128
129                 regs = (struct pt_regs *) ((unsigned long) child->thread_info +
130                        THREAD_SIZE - 32 - sizeof(struct pt_regs));
131                 ret = 0;  /* Default return value. */
132
133                 switch (addr) {
134                 case 0 ... 31:
135                         tmp = regs->regs[addr];
136                         break;
137                 case FPR_BASE ... FPR_BASE + 31:
138                         if (tsk_used_math(child)) {
139                                 fpureg_t *fregs = get_fpu_regs(child);
140
141                                 /*
142                                  * The odd registers are actually the high
143                                  * order bits of the values stored in the even
144                                  * registers - unless we're using r2k_switch.S.
145                                  */
146                                 if (addr & 1)
147                                         tmp = (unsigned long) (fregs[((addr & ~1) - 32)] >> 32);
148                                 else
149                                         tmp = (unsigned long) (fregs[(addr - 32)] & 0xffffffff);
150                         } else {
151                                 tmp = -1;       /* FP not yet used  */
152                         }
153                         break;
154                 case PC:
155                         tmp = regs->cp0_epc;
156                         break;
157                 case CAUSE:
158                         tmp = regs->cp0_cause;
159                         break;
160                 case BADVADDR:
161                         tmp = regs->cp0_badvaddr;
162                         break;
163                 case MMHI:
164                         tmp = regs->hi;
165                         break;
166                 case MMLO:
167                         tmp = regs->lo;
168                         break;
169                 case FPC_CSR:
170                         if (cpu_has_fpu)
171                                 tmp = child->thread.fpu.hard.fcr31;
172                         else
173                                 tmp = child->thread.fpu.soft.fcr31;
174                         break;
175                 case FPC_EIR: { /* implementation / version register */
176                         unsigned int flags;
177
178                         if (!cpu_has_fpu)
179                                 break;
180
181                         preempt_disable();
182                         if (cpu_has_mipsmt) {
183                                 unsigned int vpflags = dvpe();
184                                 flags = read_c0_status();
185                                 __enable_fpu();
186                                 __asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
187                                 write_c0_status(flags);
188                                 evpe(vpflags);
189                         } else {
190                                 flags = read_c0_status();
191                                 __enable_fpu();
192                                 __asm__ __volatile__("cfc1\t%0,$0": "=r" (tmp));
193                                 write_c0_status(flags);
194                         }
195                         preempt_enable();
196                         break;
197                 }
198                 case DSP_BASE ... DSP_BASE + 5:
199                         if (!cpu_has_dsp) {
200                                 tmp = 0;
201                                 ret = -EIO;
202                                 goto out_tsk;
203                         }
204                         if (child->thread.dsp.used_dsp) {
205                                 dspreg_t *dregs = __get_dsp_regs(child);
206                                 tmp = (unsigned long) (dregs[addr - DSP_BASE]);
207                         } else {
208                                 tmp = -1;       /* DSP registers yet used  */
209                         }
210                         break;
211                 case DSP_CONTROL:
212                         if (!cpu_has_dsp) {
213                                 tmp = 0;
214                                 ret = -EIO;
215                                 goto out_tsk;
216                         }
217                         tmp = child->thread.dsp.dspcontrol;
218                         break;
219                 default:
220                         tmp = 0;
221                         ret = -EIO;
222                         goto out_tsk;
223                 }
224                 ret = put_user(tmp, (unsigned *) (unsigned long) data);
225                 break;
226         }
227
228         /* when I and D space are separate, this will have to be fixed. */
229         case PTRACE_POKETEXT: /* write the word at location addr. */
230         case PTRACE_POKEDATA:
231                 ret = 0;
232                 if (access_process_vm(child, addr, &data, sizeof(data), 1)
233                     == sizeof(data))
234                         break;
235                 ret = -EIO;
236                 break;
237
238         /*
239          * Write 4 bytes into the other process' storage
240          *  data is the 4 bytes that the user wants written
241          *  addr is a pointer in the user's storage that contains an
242          *      8 byte address in the other process where the 4 bytes
243          *      that is to be written
244          * (this is run in a 32-bit process looking at a 64-bit process)
245          * when I and D space are separate, these will need to be fixed.
246          */
247         case PTRACE_POKETEXT_3264:
248         case PTRACE_POKEDATA_3264: {
249                 u32 __user * addrOthers;
250
251                 /* Get the addr in the other process that we want to write into */
252                 ret = -EIO;
253                 if (get_user(addrOthers, (u32 __user * __user *) (unsigned long) addr) != 0)
254                         break;
255                 ret = 0;
256                 if (access_process_vm(child, (u64)addrOthers, &data,
257                                         sizeof(data), 1) == sizeof(data))
258                         break;
259                 ret = -EIO;
260                 break;
261         }
262
263         case PTRACE_POKEUSR: {
264                 struct pt_regs *regs;
265                 ret = 0;
266                 regs = (struct pt_regs *) ((unsigned long) child->thread_info +
267                        THREAD_SIZE - 32 - sizeof(struct pt_regs));
268
269                 switch (addr) {
270                 case 0 ... 31:
271                         regs->regs[addr] = data;
272                         break;
273                 case FPR_BASE ... FPR_BASE + 31: {
274                         fpureg_t *fregs = get_fpu_regs(child);
275
276                         if (!tsk_used_math(child)) {
277                                 /* FP not yet used  */
278                                 memset(&child->thread.fpu.hard, ~0,
279                                        sizeof(child->thread.fpu.hard));
280                                 child->thread.fpu.hard.fcr31 = 0;
281                         }
282                         /*
283                          * The odd registers are actually the high order bits
284                          * of the values stored in the even registers - unless
285                          * we're using r2k_switch.S.
286                          */
287                         if (addr & 1) {
288                                 fregs[(addr & ~1) - FPR_BASE] &= 0xffffffff;
289                                 fregs[(addr & ~1) - FPR_BASE] |= ((unsigned long long) data) << 32;
290                         } else {
291                                 fregs[addr - FPR_BASE] &= ~0xffffffffLL;
292                                 /* Must cast, lest sign extension fill upper
293                                    bits!  */
294                                 fregs[addr - FPR_BASE] |= (unsigned int)data;
295                         }
296                         break;
297                 }
298                 case PC:
299                         regs->cp0_epc = data;
300                         break;
301                 case MMHI:
302                         regs->hi = data;
303                         break;
304                 case MMLO:
305                         regs->lo = data;
306                         break;
307                 case FPC_CSR:
308                         if (cpu_has_fpu)
309                                 child->thread.fpu.hard.fcr31 = data;
310                         else
311                                 child->thread.fpu.soft.fcr31 = data;
312                         break;
313                 case DSP_BASE ... DSP_BASE + 5:
314                         if (!cpu_has_dsp) {
315                                 ret = -EIO;
316                                 break;
317                         }
318
319                         dspreg_t *dregs = __get_dsp_regs(child);
320                         dregs[addr - DSP_BASE] = data;
321                         break;
322                 case DSP_CONTROL:
323                         if (!cpu_has_dsp) {
324                                 ret = -EIO;
325                                 break;
326                         }
327                         child->thread.dsp.dspcontrol = data;
328                         break;
329                 default:
330                         /* The rest are not allowed. */
331                         ret = -EIO;
332                         break;
333                 }
334                 break;
335                 }
336
337         case PTRACE_GETREGS:
338                 ret = ptrace_getregs (child, (__u64 __user *) (__u64) data);
339                 break;
340
341         case PTRACE_SETREGS:
342                 ret = ptrace_setregs (child, (__u64 __user *) (__u64) data);
343                 break;
344
345         case PTRACE_GETFPREGS:
346                 ret = ptrace_getfpregs (child, (__u32 __user *) (__u64) data);
347                 break;
348
349         case PTRACE_SETFPREGS:
350                 ret = ptrace_setfpregs (child, (__u32 __user *) (__u64) data);
351                 break;
352
353         case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
354         case PTRACE_CONT: { /* restart after signal. */
355                 ret = -EIO;
356                 if (!valid_signal(data))
357                         break;
358                 if (request == PTRACE_SYSCALL) {
359                         set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
360                 }
361                 else {
362                         clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
363                 }
364                 child->exit_code = data;
365                 wake_up_process(child);
366                 ret = 0;
367                 break;
368         }
369
370         /*
371          * make the child exit.  Best I can do is send it a sigkill.
372          * perhaps it should be put in the status that it wants to
373          * exit.
374          */
375         case PTRACE_KILL:
376                 ret = 0;
377                 if (child->exit_state == EXIT_ZOMBIE)   /* already dead */
378                         break;
379                 child->exit_code = SIGKILL;
380                 wake_up_process(child);
381                 break;
382
383         case PTRACE_GET_THREAD_AREA:
384                 ret = put_user(child->thread_info->tp_value,
385                                 (unsigned int __user *) (unsigned long) data);
386                 break;
387
388         case PTRACE_DETACH: /* detach a process that was attached. */
389                 ret = ptrace_detach(child, data);
390                 break;
391
392         case PTRACE_GETEVENTMSG:
393                 ret = put_user(child->ptrace_message,
394                                (unsigned int __user *) (unsigned long) data);
395                 break;
396
397         case PTRACE_GET_THREAD_AREA_3264:
398                 ret = put_user(child->thread_info->tp_value,
399                                 (unsigned long __user *) (unsigned long) data);
400                 break;
401
402         default:
403                 ret = ptrace_request(child, request, addr, data);
404                 break;
405         }
406
407 out_tsk:
408         put_task_struct(child);
409 out:
410         unlock_kernel();
411         return ret;
412 }