/*
* linux/arch/m68knommu/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/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/signal.h>
#include <linux/tracehook.h>
#include <asm/uaccess.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/processor.h>
/*
* does not yet catch signals sent when the child dies.
* in exit.c or in signal.c.
*/
/* determines which bits in the SR the user has access to. */
/* 1 = access 0 = no access */
#define SR_MASK 0x001f
/* sets the trace bits. */
#define TRACE_BITS 0x8000
/* Find the stack offset for a register, relative to thread.esp0. */
#define PT_REG(reg) ((long)&((struct pt_regs *)0)->reg)
#define SW_REG(reg) ((long)&((struct switch_stack *)0)->reg \
- sizeof(struct switch_stack))
/* Mapping from PT_xxx to the stack offset at which the register is
saved. Notice that usp has no stack-slot and needs to be treated
specially (see get_reg/put_reg below). */
static int regoff[] = {
PT_REG(d1), PT_REG(d2), PT_REG(d3), PT_REG(d4),
PT_REG(d5), SW_REG(d6), SW_REG(d7), PT_REG(a0),
PT_REG(a1), PT_REG(a2), SW_REG(a3), SW_REG(a4),
SW_REG(a5), SW_REG(a6), PT_REG(d0), -1,
PT_REG(orig_d0), PT_REG(sr), PT_REG(pc),
};
/*
* Get contents of register REGNO in task TASK.
*/
static inline long get_reg(struct task_struct *task, int regno)
{
unsigned long *addr;
if (regno == PT_USP)
addr = &task->thread.usp;
else if (regno < ARRAY_SIZE(regoff))
addr = (unsigned long *)(task->thread.esp0 + regoff[regno]);
else
return 0;
return *addr;
}
/*
* Write contents of register REGNO in task TASK.
*/
static inline int put_reg(struct task_struct *task, int regno,
unsigned long data)
{
unsigned long *addr;
if (regno == PT_USP)
addr = &task->thread.usp;
else if (regno < ARRAY_SIZE(regoff))
addr = (unsigned long *) (task->thread.esp0 + regoff[regno]);
else
return -1;
*addr = data;
return 0;
}
void user_enable_single_step(struct task_struct *task)
{
unsigned long srflags;
srflags = get_reg(task, PT_SR) | (TRACE_BITS << 16);
put_reg(task, PT_SR, srflags);
}
void user_disable_single_step(struct task_struct *task)
{
unsigned long srflags;
srflags = get_reg(task, PT_SR) & ~(TRACE_BITS << 16);
put_reg(task, PT_SR, srflags);
}
/*
* Called by kernel/ptrace.c when detaching..
*
* Make sure the single step bit is not set.
*/
void ptrace_disable(struct task_struct *child)
{
/* make sure the single step bit is not set. */
user_disable_single_step(child);
}
long arch_ptrace(struct task_struct *child, long request,
unsigned long addr, unsigned long data)
{
int ret;
int regno = addr >> 2;
unsigned long __user *datap = (unsigned long __user *) data;
switch (request) {
/* read the word at location addr in the USER area. */
case PTRACE_PEEKUSR: {
unsigned long tmp;
ret = -EIO;
if ((addr & 3) || addr > sizeof(struct user) - 3)
break;
tmp = 0; /* Default return condition */
ret = -EIO;
if (regno < 19) {
tmp = get_reg(child, regno);
if (regno == PT_SR)
tmp >>= 16;
} else if (regno >= 21 && regno < 49) {
tmp = child->thread.fp[regno - 21];
} else if (regno == 49) {
tmp = child->mm->start_code;
} else if (regno == 50) {
tmp = child->mm->start_data;
} else if (regno == 51) {
tmp = child->mm->end_code;
} else
break;
ret = put_user(tmp, datap);
break;
}
case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
ret = -EIO;
if ((addr & 3) || addr > sizeof(struct user) - 3)
break;
if (regno == PT_SR) {
data &= SR_MASK;
data <<= 16;
data |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
}
if (regno < 19) {
if (put_reg(child, regno, data))
break;
ret = 0;
break;
}
if (regno >= 21 && regno < 48)
{
child->thread.fp[regno - 21] = data;
ret = 0;
}
break;
case PTRACE_GETREGS: { /* Get all gp regs from the child. */
int i;
unsigned long tmp;
for (i = 0; i < 19; i++) {
tmp = get_reg(child, i);
if (i == PT_SR)
tmp >>= 16;
if (put_user(tmp, datap)) {
ret = -EFAULT;
break;
}
datap++;
}
ret = 0;
break;
}
case PTRACE_SETREGS: { /* Set all gp regs in the child. */
int i;
unsigned long tmp;
for (i = 0; i < 19; i++) {
if (get_user(tmp, datap)) {
ret = -EFAULT;
break;
}
if (i == PT_SR) {
tmp &= SR_MASK;
tmp <<= 16;
tmp |= get_reg(child, PT_SR) & ~(SR_MASK << 16);
}
put_reg(child, i, tmp);
datap++;
}
ret = 0;
break;
}
#ifdef PTRACE_GETFPREGS
case PTRACE_GETFPREGS: { /* Get the child FPU state. */
ret = 0;
if (copy_to_user(datap, &child->thread.fp,
sizeof(struct user_m68kfp_struct)))
ret = -EFAULT;
break;
}
#endif
#ifdef PTRACE_SETFPREGS
case PTRACE_SETFPREGS: { /* Set the child FPU state. */
ret = 0;
if (copy_from_user(&child->thread.fp, datap,
sizeof(struct user_m68kfp_struct)))
ret = -EFAULT;
break;
}
#endif
case PTRACE_GET_THREAD_AREA:
ret = put_user(task_thread_info(child)->tp_value, datap);
break;
default:
ret = ptrace_request(child, request, addr, data);
break;
}
return ret;
}
asmlinkage int syscall_trace_enter(void)
{
int ret = 0;
if (test_thread_flag(TIF_SYSCALL_TRACE))
ret = tracehook_report_syscall_entry(task_pt_regs(current));
return ret;
}
asmlinkage void syscall_trace_leave(void)
{
if (test_thread_flag(TIF_SYSCALL_TRACE))
tracehook_report_syscall_exit(task_pt_regs(current), 0);
}
