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>
23 #include <asm/uaccess.h>
25 #include <asm/pgtable.h>
26 #include <asm/system.h>
27 #include <asm/processor.h>
30 * does not yet catch signals sent when the child dies.
31 * in exit.c or in signal.c.
34 /* determines which bits in the SR the user has access to. */
35 /* 1 = access 0 = no access */
36 #define SR_MASK 0x001f
38 /* sets the trace bits. */
39 #define TRACE_BITS 0x8000
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). */
48 static int regoff[] = {
65 [16] = PT_REG(orig_d0),
71 * Get contents of register REGNO in task TASK.
73 static inline long get_reg(struct task_struct *task, int regno)
78 addr = &task->thread.usp;
79 else if (regno < sizeof(regoff)/sizeof(regoff[0]))
80 addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
87 * Write contents of register REGNO in task TASK.
89 static inline int put_reg(struct task_struct *task, int regno,
95 addr = &task->thread.usp;
96 else if (regno < sizeof(regoff)/sizeof(regoff[0]))
97 addr = (unsigned long *) (task->thread.esp0 + regoff[regno]);
105 * Called by kernel/ptrace.c when detaching..
107 * Make sure the single step bit is not set.
109 void ptrace_disable(struct task_struct *child)
112 /* make sure the single step bit is not set. */
113 tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
114 put_reg(child, PT_SR, tmp);
115 child->thread.work.delayed_trace = 0;
116 child->thread.work.syscall_trace = 0;
119 asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
121 struct task_struct *child;
126 if (request == PTRACE_TRACEME) {
127 /* are we already being traced? */
128 if (current->ptrace & PT_PTRACED)
130 /* set the ptrace bit in the process flags. */
131 current->ptrace |= PT_PTRACED;
136 read_lock(&tasklist_lock);
137 child = find_task_by_pid(pid);
139 get_task_struct(child);
140 read_unlock(&tasklist_lock);
143 if (!vx_check(vx_task_xid(child), VX_WATCH|VX_IDENT))
147 if (pid == 1) /* you may not mess with init */
150 if (request == PTRACE_ATTACH) {
151 ret = ptrace_attach(child);
155 ret = ptrace_check_attach(child, request == PTRACE_KILL);
160 /* when I and D space are separate, these will need to be fixed. */
161 case PTRACE_PEEKTEXT: /* read word at location addr. */
162 case PTRACE_PEEKDATA: {
166 copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
168 if (copied != sizeof(tmp))
170 ret = put_user(tmp,(unsigned long *) data);
174 /* read the word at location addr in the USER area. */
175 case PTRACE_PEEKUSR: {
179 if ((addr & 3) || addr < 0 ||
180 addr > sizeof(struct user) - 3)
183 tmp = 0; /* Default return condition */
184 addr = addr >> 2; /* temporary hack. */
187 tmp = get_reg(child, addr);
190 } else if (addr >= 21 && addr < 49) {
191 tmp = child->thread.fp[addr - 21];
192 #ifdef CONFIG_M68KFPU_EMU
193 /* Convert internal fpu reg representation
194 * into long double format
196 if (FPU_IS_EMU && (addr < 45) && !(addr % 3))
197 tmp = ((tmp & 0xffff0000) << 15) |
198 ((tmp & 0x0000ffff) << 16);
202 ret = put_user(tmp,(unsigned long *) data);
206 /* when I and D space are separate, this will have to be fixed. */
207 case PTRACE_POKETEXT: /* write the word at location addr. */
208 case PTRACE_POKEDATA:
210 if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
215 case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
217 if ((addr & 3) || addr < 0 ||
218 addr > sizeof(struct user) - 3)
221 addr = addr >> 2; /* temporary hack. */
226 data |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
229 if (put_reg(child, addr, data))
234 if (addr >= 21 && addr < 48)
236 #ifdef CONFIG_M68KFPU_EMU
237 /* Convert long double format
238 * into internal fpu reg representation
240 if (FPU_IS_EMU && (addr < 45) && !(addr % 3)) {
241 data = (unsigned long)data << 15;
242 data = (data & 0xffff0000) |
243 ((data & 0x0000ffff) >> 1);
246 child->thread.fp[addr - 21] = data;
251 case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
252 case PTRACE_CONT: { /* restart after signal. */
256 if ((unsigned long) data > _NSIG)
258 if (request == PTRACE_SYSCALL) {
259 child->thread.work.syscall_trace = ~0;
261 child->thread.work.syscall_trace = 0;
263 child->exit_code = data;
264 /* make sure the single step bit is not set. */
265 tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
266 put_reg(child, PT_SR, tmp);
267 child->thread.work.delayed_trace = 0;
268 wake_up_process(child);
274 * make the child exit. Best I can do is send it a sigkill.
275 * perhaps it should be put in the status that it wants to
282 if (child->state == TASK_ZOMBIE) /* already dead */
284 child->exit_code = SIGKILL;
285 /* make sure the single step bit is not set. */
286 tmp = get_reg(child, PT_SR) & ~(TRACE_BITS << 16);
287 put_reg(child, PT_SR, tmp);
288 child->thread.work.delayed_trace = 0;
289 wake_up_process(child);
293 case PTRACE_SINGLESTEP: { /* set the trap flag. */
297 if ((unsigned long) data > _NSIG)
299 child->thread.work.syscall_trace = 0;
300 tmp = get_reg(child, PT_SR) | (TRACE_BITS << 16);
301 put_reg(child, PT_SR, tmp);
302 child->thread.work.delayed_trace = 1;
304 child->exit_code = data;
305 /* give it a chance to run. */
306 wake_up_process(child);
311 case PTRACE_DETACH: /* detach a process that was attached. */
312 ret = ptrace_detach(child, data);
315 case PTRACE_GETREGS: { /* Get all gp regs from the child. */
318 for (i = 0; i < 19; i++) {
319 tmp = get_reg(child, i);
322 if (put_user(tmp, (unsigned long *) data)) {
326 data += sizeof(long);
332 case PTRACE_SETREGS: { /* Set all gp regs in the child. */
335 for (i = 0; i < 19; i++) {
336 if (get_user(tmp, (unsigned long *) data)) {
343 tmp |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
345 put_reg(child, i, tmp);
346 data += sizeof(long);
352 case PTRACE_GETFPREGS: { /* Get the child FPU state. */
354 if (copy_to_user((void *)data, &child->thread.fp,
355 sizeof(struct user_m68kfp_struct)))
360 case PTRACE_SETFPREGS: { /* Set the child FPU state. */
362 if (copy_from_user(&child->thread.fp, (void *)data,
363 sizeof(struct user_m68kfp_struct)))
369 ret = ptrace_request(child, request, addr, data);
373 put_task_struct(child);
379 asmlinkage void syscall_trace(void)
381 if (!current->thread.work.delayed_trace &&
382 !current->thread.work.syscall_trace)
384 current->exit_code = SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
386 current->state = TASK_STOPPED;
387 notify_parent(current, SIGCHLD);
390 * this isn't the same as continuing with a signal, but it will do
391 * for normal use. strace only continues with a signal if the
392 * stopping signal is not SIGTRAP. -brl
394 if (current->exit_code) {
395 send_sig(current->exit_code, current, 1);
396 current->exit_code = 0;