2 * linux/arch/m68k/kernel/ptrace.c
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
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.
13 #include <linux/kernel.h>
14 #include <linux/sched.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 #include <linux/signal.h>
24 #include <asm/uaccess.h>
26 #include <asm/pgtable.h>
27 #include <asm/system.h>
28 #include <asm/processor.h>
31 * does not yet catch signals sent when the child dies.
32 * in exit.c or in signal.c.
35 /* determines which bits in the SR the user has access to. */
36 /* 1 = access 0 = no access */
37 #define SR_MASK 0x001f
39 /* sets the trace bits. */
40 #define TRACE_BITS 0x8000
42 /* Find the stack offset for a register, relative to thread.esp0. */
43 #define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg)
44 #define SW_REG(reg) ((long)&((struct switch_stack *)0)->reg \
45 - sizeof(struct switch_stack))
46 /* Mapping from PT_xxx to the stack offset at which the register is
47 saved. Notice that usp has no stack-slot and needs to be treated
48 specially (see get_reg/put_reg below). */
49 static int regoff[] = {
66 [16] = PT_REG(orig_d0),
72 * Get contents of register REGNO in task TASK.
74 static inline long get_reg(struct task_struct *task, int regno)
79 addr = &task->thread.usp;
80 else if (regno < sizeof(regoff)/sizeof(regoff[0]))
81 addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
88 * Write contents of register REGNO in task TASK.
90 static inline int put_reg(struct task_struct *task, int regno,
96 addr = &task->thread.usp;
97 else if (regno < sizeof(regoff)/sizeof(regoff[0]))
98 addr = (unsigned long *) (task->thread.esp0 + regoff[regno]);
106 * Called by kernel/ptrace.c when detaching..
108 * Make sure the single step bit is not set.
110 void ptrace_disable(struct task_struct *child)
113 /* make sure the single step bit is not set. */
114 tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
115 put_reg(child, PT_SR, tmp);
116 child->thread.work.delayed_trace = 0;
117 child->thread.work.syscall_trace = 0;
120 asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
122 struct task_struct *child;
127 if (request == PTRACE_TRACEME) {
128 /* are we already being traced? */
129 if (current->ptrace & PT_PTRACED)
131 /* set the ptrace bit in the process flags. */
132 current->ptrace |= PT_PTRACED;
137 read_lock(&tasklist_lock);
138 child = find_task_by_pid(pid);
140 get_task_struct(child);
141 read_unlock(&tasklist_lock);
144 if (!vx_check(vx_task_xid(child), VX_WATCH|VX_IDENT))
148 if (pid == 1) /* you may not mess with init */
151 if (request == PTRACE_ATTACH) {
152 ret = ptrace_attach(child);
156 ret = ptrace_check_attach(child, request == PTRACE_KILL);
161 /* when I and D space are separate, these will need to be fixed. */
162 case PTRACE_PEEKTEXT: /* read word at location addr. */
163 case PTRACE_PEEKDATA: {
167 copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
169 if (copied != sizeof(tmp))
171 ret = put_user(tmp,(unsigned long *) data);
175 /* read the word at location addr in the USER area. */
176 case PTRACE_PEEKUSR: {
180 if ((addr & 3) || addr < 0 ||
181 addr > sizeof(struct user) - 3)
184 tmp = 0; /* Default return condition */
185 addr = addr >> 2; /* temporary hack. */
188 tmp = get_reg(child, addr);
191 } else if (addr >= 21 && addr < 49) {
192 tmp = child->thread.fp[addr - 21];
193 #ifdef CONFIG_M68KFPU_EMU
194 /* Convert internal fpu reg representation
195 * into long double format
197 if (FPU_IS_EMU && (addr < 45) && !(addr % 3))
198 tmp = ((tmp & 0xffff0000) << 15) |
199 ((tmp & 0x0000ffff) << 16);
203 ret = put_user(tmp,(unsigned long *) data);
207 /* when I and D space are separate, this will have to be fixed. */
208 case PTRACE_POKETEXT: /* write the word at location addr. */
209 case PTRACE_POKEDATA:
211 if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
216 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
218 if ((addr & 3) || addr < 0 ||
219 addr > sizeof(struct user) - 3)
222 addr = addr >> 2; /* temporary hack. */
227 data |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
230 if (put_reg(child, addr, data))
235 if (addr >= 21 && addr < 48)
237 #ifdef CONFIG_M68KFPU_EMU
238 /* Convert long double format
239 * into internal fpu reg representation
241 if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) {
242 data = (unsigned long)data << 15;
243 data = (data & 0xffff0000) |
244 ((data & 0x0000ffff) >> 1);
247 child->thread.fp[addr - 21] = data;
252 case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
253 case PTRACE_CONT: { /* restart after signal. */
257 if (!valid_signal(data))
259 if (request == PTRACE_SYSCALL) {
260 child->thread.work.syscall_trace = ~0;
262 child->thread.work.syscall_trace = 0;
264 child->exit_code = data;
265 /* make sure the single step bit is not set. */
266 tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
267 put_reg(child, PT_SR, tmp);
268 child->thread.work.delayed_trace = 0;
269 wake_up_process(child);
275 * make the child exit. Best I can do is send it a sigkill.
276 * perhaps it should be put in the status that it wants to
283 if (child->exit_state == EXIT_ZOMBIE) /* already dead */
285 child->exit_code = SIGKILL;
286 /* make sure the single step bit is not set. */
287 tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
288 put_reg(child, PT_SR, tmp);
289 child->thread.work.delayed_trace = 0;
290 wake_up_process(child);
294 case PTRACE_SINGLESTEP: { /* set the trap flag. */
298 if (!valid_signal(data))
300 child->thread.work.syscall_trace = 0;
301 tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16);
302 put_reg(child, PT_SR, tmp);
303 child->thread.work.delayed_trace = 1;
305 child->exit_code = data;
306 /* give it a chance to run. */
307 wake_up_process(child);
312 case PTRACE_DETACH: /* detach a process that was attached. */
313 ret = ptrace_detach(child, data);
316 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
319 for (i = 0; i < 19; i++) {
320 tmp = get_reg(child, i);
323 if (put_user(tmp, (unsigned long *) data)) {
327 data += sizeof(long);
333 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
336 for (i = 0; i < 19; i++) {
337 if (get_user(tmp, (unsigned long *) data)) {
344 tmp |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
346 put_reg(child, i, tmp);
347 data += sizeof(long);
353 case PTRACE_GETFPREGS: { /* Get the child FPU state. */
355 if (copy_to_user((void *)data, &child->thread.fp,
356 sizeof(struct user_m68kfp_struct)))
361 case PTRACE_SETFPREGS: { /* Set the child FPU state. */
363 if (copy_from_user(&child->thread.fp, (void *)data,
364 sizeof(struct user_m68kfp_struct)))
370 ret = ptrace_request(child, request, addr, data);
374 put_task_struct(child);
380 asmlinkage void syscall_trace(void)
382 if (!current->thread.work.delayed_trace &&
383 !current->thread.work.syscall_trace)
385 ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
388 * this isn't the same as continuing with a signal, but it will do
389 * for normal use. strace only continues with a signal if the
390 * stopping signal is not SIGTRAP. -brl
392 if (current->exit_code) {
393 send_sig(current->exit_code, current, 1);
394 current->exit_code = 0;