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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/m68knommu/kernel/ptrace.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/m68knommu/kernel/ptrace.c')
-rw-r--r--arch/m68knommu/kernel/ptrace.c383
1 files changed, 383 insertions, 0 deletions
diff --git a/arch/m68knommu/kernel/ptrace.c b/arch/m68knommu/kernel/ptrace.c
new file mode 100644
index 000000000000..15cf79080b15
--- /dev/null
+++ b/arch/m68knommu/kernel/ptrace.c
@@ -0,0 +1,383 @@
1/*
2 * linux/arch/m68knommu/kernel/ptrace.c
3 *
4 * Copyright (C) 1994 by Hamish Macdonald
5 * Taken from linux/kernel/ptrace.c and modified for M680x0.
6 * linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
7 *
8 * This file is subject to the terms and conditions of the GNU General
9 * Public License. See the file COPYING in the main directory of
10 * this archive for more details.
11 */
12
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/mm.h>
16#include <linux/smp.h>
17#include <linux/smp_lock.h>
18#include <linux/errno.h>
19#include <linux/ptrace.h>
20#include <linux/user.h>
21#include <linux/config.h>
22
23#include <asm/uaccess.h>
24#include <asm/page.h>
25#include <asm/pgtable.h>
26#include <asm/system.h>
27#include <asm/processor.h>
28
29/*
30 * does not yet catch signals sent when the child dies.
31 * in exit.c or in signal.c.
32 */
33
34/* determines which bits in the SR the user has access to. */
35/* 1 = access 0 = no access */
36#define SR_MASK 0x001f
37
38/* sets the trace bits. */
39#define TRACE_BITS 0x8000
40
41/* Find the stack offset for a register, relative to thread.esp0. */
42#define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg)
43#define SW_REG(reg) ((long)&((struct switch_stack *)0)->reg \
44 - sizeof(struct switch_stack))
45/* Mapping from PT_xxx to the stack offset at which the register is
46 saved. Notice that usp has no stack-slot and needs to be treated
47 specially (see get_reg/put_reg below). */
48static int regoff[] = {
49 PT_REG(d1), PT_REG(d2), PT_REG(d3), PT_REG(d4),
50 PT_REG(d5), SW_REG(d6), SW_REG(d7), PT_REG(a0),
51 PT_REG(a1), PT_REG(a2), SW_REG(a3), SW_REG(a4),
52 SW_REG(a5), SW_REG(a6), PT_REG(d0), -1,
53 PT_REG(orig_d0), PT_REG(sr), PT_REG(pc),
54};
55
56/*
57 * Get contents of register REGNO in task TASK.
58 */
59static inline long get_reg(struct task_struct *task, int regno)
60{
61 unsigned long *addr;
62
63 if (regno == PT_USP)
64 addr = &task->thread.usp;
65 else if (regno < sizeof(regoff)/sizeof(regoff[0]))
66 addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
67 else
68 return 0;
69 return *addr;
70}
71
72/*
73 * Write contents of register REGNO in task TASK.
74 */
75static inline int put_reg(struct task_struct *task, int regno,
76 unsigned long data)
77{
78 unsigned long *addr;
79
80 if (regno == PT_USP)
81 addr = &task->thread.usp;
82 else if (regno < sizeof(regoff)/sizeof(regoff[0]))
83 addr = (unsigned long *) (task->thread.esp0 + regoff[regno]);
84 else
85 return -1;
86 *addr = data;
87 return 0;
88}
89
90/*
91 * Called by kernel/ptrace.c when detaching..
92 *
93 * Make sure the single step bit is not set.
94 */
95void ptrace_disable(struct task_struct *child)
96{
97 unsigned long tmp;
98 /* make sure the single step bit is not set. */
99 tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
100 put_reg(child, PT_SR, tmp);
101}
102
103asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
104{
105 struct task_struct *child;
106 int ret;
107
108 lock_kernel();
109 ret = -EPERM;
110 if (request == PTRACE_TRACEME) {
111 /* are we already being traced? */
112 if (current->ptrace & PT_PTRACED)
113 goto out;
114 /* set the ptrace bit in the process flags. */
115 current->ptrace |= PT_PTRACED;
116 ret = 0;
117 goto out;
118 }
119 ret = -ESRCH;
120 read_lock(&tasklist_lock);
121 child = find_task_by_pid(pid);
122 if (child)
123 get_task_struct(child);
124 read_unlock(&tasklist_lock);
125 if (!child)
126 goto out;
127
128 ret = -EPERM;
129 if (pid == 1) /* you may not mess with init */
130 goto out_tsk;
131
132 if (request == PTRACE_ATTACH) {
133 ret = ptrace_attach(child);
134 goto out_tsk;
135 }
136 ret = ptrace_check_attach(child, request == PTRACE_KILL);
137 if (ret < 0)
138 goto out_tsk;
139
140 switch (request) {
141 /* when I and D space are separate, these will need to be fixed. */
142 case PTRACE_PEEKTEXT: /* read word at location addr. */
143 case PTRACE_PEEKDATA: {
144 unsigned long tmp;
145 int copied;
146
147 copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
148 ret = -EIO;
149 if (copied != sizeof(tmp))
150 break;
151 ret = put_user(tmp,(unsigned long *) data);
152 break;
153 }
154
155 /* read the word at location addr in the USER area. */
156 case PTRACE_PEEKUSR: {
157 unsigned long tmp;
158
159 ret = -EIO;
160 if ((addr & 3) || addr < 0 ||
161 addr > sizeof(struct user) - 3)
162 break;
163
164 tmp = 0; /* Default return condition */
165 addr = addr >> 2; /* temporary hack. */
166 ret = -EIO;
167 if (addr < 19) {
168 tmp = get_reg(child, addr);
169 if (addr == PT_SR)
170 tmp >>= 16;
171 } else if (addr >= 21 && addr < 49) {
172 tmp = child->thread.fp[addr - 21];
173#ifdef CONFIG_M68KFPU_EMU
174 /* Convert internal fpu reg representation
175 * into long double format
176 */
177 if (FPU_IS_EMU && (addr < 45) && !(addr % 3))
178 tmp = ((tmp & 0xffff0000) << 15) |
179 ((tmp & 0x0000ffff) << 16);
180#endif
181 } else if (addr == 49) {
182 tmp = child->mm->start_code;
183 } else if (addr == 50) {
184 tmp = child->mm->start_data;
185 } else if (addr == 51) {
186 tmp = child->mm->end_code;
187 } else
188 break;
189 ret = put_user(tmp,(unsigned long *) data);
190 break;
191 }
192
193 /* when I and D space are separate, this will have to be fixed. */
194 case PTRACE_POKETEXT: /* write the word at location addr. */
195 case PTRACE_POKEDATA:
196 ret = 0;
197 if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
198 break;
199 ret = -EIO;
200 break;
201
202 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
203 ret = -EIO;
204 if ((addr & 3) || addr < 0 ||
205 addr > sizeof(struct user) - 3)
206 break;
207
208 addr = addr >> 2; /* temporary hack. */
209
210 if (addr == PT_SR) {
211 data &= SR_MASK;
212 data <<= 16;
213 data |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
214 }
215 if (addr < 19) {
216 if (put_reg(child, addr, data))
217 break;
218 ret = 0;
219 break;
220 }
221 if (addr >= 21 && addr < 48)
222 {
223#ifdef CONFIG_M68KFPU_EMU
224 /* Convert long double format
225 * into internal fpu reg representation
226 */
227 if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) {
228 data = (unsigned long)data << 15;
229 data = (data & 0xffff0000) |
230 ((data & 0x0000ffff) >> 1);
231 }
232#endif
233 child->thread.fp[addr - 21] = data;
234 ret = 0;
235 }
236 break;
237
238 case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
239 case PTRACE_CONT: { /* restart after signal. */
240 long tmp;
241
242 ret = -EIO;
243 if ((unsigned long) data > _NSIG)
244 break;
245 if (request == PTRACE_SYSCALL)
246 set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
247 else
248 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
249 child->exit_code = data;
250 /* make sure the single step bit is not set. */
251 tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
252 put_reg(child, PT_SR, tmp);
253 wake_up_process(child);
254 ret = 0;
255 break;
256 }
257
258 /*
259 * make the child exit. Best I can do is send it a sigkill.
260 * perhaps it should be put in the status that it wants to
261 * exit.
262 */
263 case PTRACE_KILL: {
264 long tmp;
265
266 ret = 0;
267 if (child->exit_state == EXIT_ZOMBIE) /* already dead */
268 break;
269 child->exit_code = SIGKILL;
270 /* make sure the single step bit is not set. */
271 tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
272 put_reg(child, PT_SR, tmp);
273 wake_up_process(child);
274 break;
275 }
276
277 case PTRACE_SINGLESTEP: { /* set the trap flag. */
278 long tmp;
279
280 ret = -EIO;
281 if ((unsigned long) data > _NSIG)
282 break;
283 clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
284 tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16);
285 put_reg(child, PT_SR, tmp);
286
287 child->exit_code = data;
288 /* give it a chance to run. */
289 wake_up_process(child);
290 ret = 0;
291 break;
292 }
293
294 case PTRACE_DETACH: /* detach a process that was attached. */
295 ret = ptrace_detach(child, data);
296 break;
297
298 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
299 int i;
300 unsigned long tmp;
301 for (i = 0; i < 19; i++) {
302 tmp = get_reg(child, i);
303 if (i == PT_SR)
304 tmp >>= 16;
305 if (put_user(tmp, (unsigned long *) data)) {
306 ret = -EFAULT;
307 break;
308 }
309 data += sizeof(long);
310 }
311 ret = 0;
312 break;
313 }
314
315 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
316 int i;
317 unsigned long tmp;
318 for (i = 0; i < 19; i++) {
319 if (get_user(tmp, (unsigned long *) data)) {
320 ret = -EFAULT;
321 break;
322 }
323 if (i == PT_SR) {
324 tmp &= SR_MASK;
325 tmp <<= 16;
326 tmp |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
327 }
328 put_reg(child, i, tmp);
329 data += sizeof(long);
330 }
331 ret = 0;
332 break;
333 }
334
335#ifdef PTRACE_GETFPREGS
336 case PTRACE_GETFPREGS: { /* Get the child FPU state. */
337 ret = 0;
338 if (copy_to_user((void *)data, &child->thread.fp,
339 sizeof(struct user_m68kfp_struct)))
340 ret = -EFAULT;
341 break;
342 }
343#endif
344
345#ifdef PTRACE_SETFPREGS
346 case PTRACE_SETFPREGS: { /* Set the child FPU state. */
347 ret = 0;
348 if (copy_from_user(&child->thread.fp, (void *)data,
349 sizeof(struct user_m68kfp_struct)))
350 ret = -EFAULT;
351 break;
352 }
353#endif
354
355 default:
356 ret = -EIO;
357 break;
358 }
359out_tsk:
360 put_task_struct(child);
361out:
362 unlock_kernel();
363 return ret;
364}
365
366asmlinkage void syscall_trace(void)
367{
368 if (!test_thread_flag(TIF_SYSCALL_TRACE))
369 return;
370 if (!(current->ptrace & PT_PTRACED))
371 return;
372 ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
373 ? 0x80 : 0));
374 /*
375 * this isn't the same as continuing with a signal, but it will do
376 * for normal use. strace only continues with a signal if the
377 * stopping signal is not SIGTRAP. -brl
378 */
379 if (current->exit_code) {
380 send_sig(current->exit_code, current, 1);
381 current->exit_code = 0;
382 }
383}