/*
* linux/arch/h8300/kernel/ptrace.c
*
* Yoshinori Sato <ysato@users.sourceforge.jp>
*
* Based on:
* linux/arch/m68k/kernel/ptrace.c
*
* Copyright (C) 1994 by Hamish Macdonald
* Taken from linux/kernel/ptrace.c and modified for M680x0.
* linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
*
* This file is subject to the terms and conditions of the GNU General
* Public License. See the file COPYING in the main directory of
* this archive for more details.
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/config.h>
#include <linux/signal.h>
#include <asm/uaccess.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/processor.h>
#include <asm/signal.h>
/* cpu depend functions */
extern long h8300_get_reg(struct task_struct *task, int regno);
extern int h8300_put_reg(struct task_struct *task, int regno, unsigned long data);
extern void h8300_disable_trace(struct task_struct *child);
extern void h8300_enable_trace(struct task_struct *child);
/*
* does not yet catch signals sent when the child dies.
* in exit.c or in signal.c.
*/
inline
static int read_long(struct task_struct * tsk, unsigned long addr,
unsigned long * result)
{
*result = *(unsigned long *)addr;
return 0;
}
void ptrace_disable(struct task_struct *child)
{
h8300_disable_trace(child);
}
asmlinkage int sys_ptrace(long request, long pid, long addr, long data)
{
struct task_struct *child;
int ret;
lock_kernel();
ret = -EPERM;
if (request == PTRACE_TRACEME) {
/* are we already being traced? */
if (current->ptrace & PT_PTRACED)
goto out;
/* set the ptrace bit in the process flags. */
current->ptrace |= PT_PTRACED;
ret = 0;
goto out;
}
ret = -ESRCH;
read_lock(&tasklist_lock);
child = find_task_by_pid(pid);
if (child)
get_task_struct(child);
read_unlock(&tasklist_lock);
if (!child)
goto out;
ret = -EPERM;
if (pid == 1) /* you may not mess with init */
goto out_tsk;
if (request == PTRACE_ATTACH) {
ret = ptrace_attach(child);
goto out_tsk;
}
ret = ptrace_check_attach(child, request == PTRACE_KILL);
if (ret < 0)
goto out_tsk;
switch (request) {
case PTRACE_PEEKTEXT: /* read word at location addr. */
case PTRACE_PEEKDATA: {
unsigned long tmp;
ret = read_long(child, addr, &tmp);
if (ret < 0)
break ;
ret = put_user(tmp, (unsigned long *) data);
break ;
}
/* read the word at location addr in the USER area. */
case PTRACE_PEEKUSR: {
unsigned long tmp = 0;
if ((addr & 3) || addr < 0 || addr >= sizeof(struct user)) {
ret = -EIO;
break ;
}
ret = 0; /* Default return condition */
addr = addr >> 2; /* temporary hack. */
if (addr < H8300_REGS_NO)
tmp = h8300_get_reg(child, addr);
else {
switch(addr) {
case 49:
tmp = child->mm->start_code;
break ;
case 50:
tmp = child->mm->start_data;
break ;
case 51:
tmp = child->mm->end_code;
break ;
case 52:
tmp = child->mm->end_data;
break ;
default:
ret = -EIO;
}
}
if (!ret)
ret = put_user(tmp,(unsigned long *) data);
break ;
}
/* when I and D space are separate, this will have to be fixed. */
case PTRACE_POKETEXT: /* write the word at location addr. */
case PTRACE_POKEDATA:
ret = 0;
if (access_process_vm(child, addr, &data, sizeof(data), 1) == sizeof(data))
break;
ret = -EIO;
break;
case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
if ((addr & 3) || addr < 0 || addr >= sizeof(struct user)) {
ret = -EIO;
break ;
}
addr = addr >> 2; /* temporary hack. */
if (addr == PT_ORIG_ER0) {
ret = -EIO;
break ;
}
if (addr < H8300_REGS_NO) {
ret = h8300_put_reg(child, addr, data);
break ;
}
ret = -EIO;
break ;
case PTRACE_SYSCALL: /* continue and stop at next (return from) syscall */
case PTRACE_CONT: { /* restart after signal. */
ret = -EIO;
if (!valid_signal(data))
break ;
if (request == PTRACE_SYSCALL)
set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
else
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
child->exit_code = data;
wake_up_process(child);
/* make sure the single step bit is not set. */
h8300_disable_trace(child);
ret = 0;
}
/*
* make the child exit. Best I can do is send it a sigkill.
* perhaps it should be put in the status that it wants to
* exit.
*/
case PTRACE_KILL: {
ret = 0;
if (child->exit_state == EXIT_ZOMBIE) /* already dead */
break;
child->exit_code = SIGKILL;
h8300_disable_trace(child);
wake_up_process(child);
break;
}
case PTRACE_SINGLESTEP: { /* set the trap flag. */
ret = -EIO;
if (!valid_signal(data))
break;
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
child->exit_code = data;
h8300_enable_trace(child);
wake_up_process(child);
ret = 0;
break;
}
case PTRACE_DETACH: /* detach a process that was attached. */
ret = ptrace_detach(child, data);
break;
case PTRACE_GETREGS: { /* Get all gp regs from the child. */
int i;
unsigned long tmp;
for (i = 0; i < H8300_REGS_NO; i++) {
tmp = h8300_get_reg(child, i);
if (put_user(tmp, (unsigned long *) data)) {
ret = -EFAULT;
break;
}
data += sizeof(long);
}
ret = 0;
break;
}
case PTRACE_SETREGS: { /* Set all gp regs in the child. */
int i;
unsigned long tmp;
for (i = 0; i < H8300_REGS_NO; i++) {
if (get_user(tmp, (unsigned long *) data)) {
ret = -EFAULT;
break;
}
h8300_put_reg(child, i, tmp);
data += sizeof(long);
}
ret = 0;
break;
}
default:
ret = -EIO;
break;
}
out_tsk:
put_task_struct(child);
out:
unlock_kernel();
return ret;
}
asmlinkage void syscall_trace(void)
{
if (!test_thread_flag(TIF_SYSCALL_TRACE))
return;
if (!(current->ptrace & PT_PTRACED))
return;
ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD)
? 0x80 : 0));
/*
* this isn't the same as continuing with a signal, but it will do
* for normal use. strace only continues with a signal if the
* stopping signal is not SIGTRAP. -brl
*/
if (current->exit_code) {
send_sig(current->exit_code, current, 1);
current->exit_code = 0;
}
}
