/* MN10300 Process tracing
*
* Copyright (C) 2007 Matsushita Electric Industrial Co., Ltd.
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Modified by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#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 <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/system.h>
#include <asm/processor.h>
#include <asm/cacheflush.h>
#include <asm/fpu.h>
#include <asm/asm-offsets.h>
/*
* translate ptrace register IDs into struct pt_regs offsets
*/
static const u8 ptrace_regid_to_frame[] = {
[PT_A3 << 2] = REG_A3,
[PT_A2 << 2] = REG_A2,
[PT_D3 << 2] = REG_D3,
[PT_D2 << 2] = REG_D2,
[PT_MCVF << 2] = REG_MCVF,
[PT_MCRL << 2] = REG_MCRL,
[PT_MCRH << 2] = REG_MCRH,
[PT_MDRQ << 2] = REG_MDRQ,
[PT_E1 << 2] = REG_E1,
[PT_E0 << 2] = REG_E0,
[PT_E7 << 2] = REG_E7,
[PT_E6 << 2] = REG_E6,
[PT_E5 << 2] = REG_E5,
[PT_E4 << 2] = REG_E4,
[PT_E3 << 2] = REG_E3,
[PT_E2 << 2] = REG_E2,
[PT_SP << 2] = REG_SP,
[PT_LAR << 2] = REG_LAR,
[PT_LIR << 2] = REG_LIR,
[PT_MDR << 2] = REG_MDR,
[PT_A1 << 2] = REG_A1,
[PT_A0 << 2] = REG_A0,
[PT_D1 << 2] = REG_D1,
[PT_D0 << 2] = REG_D0,
[PT_ORIG_D0 << 2] = REG_ORIG_D0,
[PT_EPSW << 2] = REG_EPSW,
[PT_PC << 2] = REG_PC,
};
static inline int get_stack_long(struct task_struct *task, int offset)
{
return *(unsigned long *)
((unsigned long) task->thread.uregs + offset);
}
/*
* this routine will put a word on the processes privileged stack.
* the offset is how far from the base addr as stored in the TSS.
* this routine assumes that all the privileged stacks are in our
* data space.
*/
static inline
int put_stack_long(struct task_struct *task, int offset, unsigned long data)
{
unsigned long stack;
stack = (unsigned long) task->thread.uregs + offset;
*(unsigned long *) stack = data;
return 0;
}
static inline unsigned long get_fpregs(struct fpu_state_struct *buf,
struct task_struct *tsk)
{
return __copy_to_user(buf, &tsk->thread.fpu_state,
sizeof(struct fpu_state_struct));
}
static inline unsigned long set_fpregs(struct task_struct *tsk,
struct fpu_state_struct *buf)
{
return __copy_from_user(&tsk->thread.fpu_state, buf,
sizeof(struct fpu_state_struct));
}
static inline void fpsave_init(struct task_struct *task)
{
memset(&task->thread.fpu_state, 0, sizeof(struct fpu_state_struct));
}
/*
* make sure the single step bit is not set
*/
void ptrace_disable(struct task_struct *child)
{
#ifndef CONFIG_MN10300_USING_JTAG
struct user *dummy = NULL;
long tmp;
tmp = get_stack_long(child, (unsigned long) &dummy->regs.epsw);
tmp &= ~EPSW_T;
put_stack_long(child, (unsigned long) &dummy->regs.epsw, tmp);
#endif
}
/*
* set the single step bit
*/
void ptrace_enable(struct task_struct *child)
{
#ifndef CONFIG_MN10300_USING_JTAG
struct user *dummy = NULL;
long tmp;
tmp = get_stack_long(child, (unsigned long) &dummy->regs.epsw);
tmp |= EPSW_T;
put_stack_long(child, (unsigned long) &dummy->regs.epsw, tmp);
#endif
}
/*
* handle the arch-specific side of process tracing
*/
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
struct fpu_state_struct fpu_state;
int i, ret;
switch (request) {
/* read the word at location addr. */
case PTRACE_PEEKTEXT: {
unsigned long tmp;
int copied;
copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
ret = -EIO;
if (copied != sizeof(tmp))
break;
ret = put_user(tmp, (unsigned long *) data);
break;
}
/* read the word at location addr. */
case PTRACE_PEEKDATA: {
unsigned long tmp;
int copied;
copied = access_process_vm(child, addr, &tmp, sizeof(tmp), 0);
ret = -EIO;
if (copied != sizeof(tmp))
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;
ret = -EIO;
if ((addr & 3) || addr < 0 ||
addr > sizeof(struct user) - 3)
break;
tmp = 0; /* Default return condition */
if (addr < NR_PTREGS << 2)
tmp = get_stack_long(child,
ptrace_regid_to_frame[addr]);
ret = put_user(tmp, (unsigned long *) data);
break;
}
/* write the word at location addr. */
case PTRACE_POKETEXT:
case PTRACE_POKEDATA:
if (access_process_vm(child, addr, &data, sizeof(data), 1) ==
sizeof(data))
ret = 0;
else
ret = -EIO;
break;
/* write the word at location addr in the USER area */
case PTRACE_POKEUSR:
ret = -EIO;
if ((addr & 3) || addr < 0 ||
addr > sizeof(struct user) - 3)
break;
ret = 0;
if (addr < NR_PTREGS << 2)
ret = put_stack_long(child, ptrace_regid_to_frame[addr],
data);
break;
/* continue and stop at next (return from) syscall */
case PTRACE_SYSCALL:
/* restart after signal. */
case PTRACE_CONT:
ret = -EIO;
if ((unsigned long) data > _NSIG)
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;
ptrace_disable(child);
wake_up_process(child);
ret = 0;
break;
/*
* make the child exit
* - the 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;
clear_tsk_thread_flag(child, TIF_SINGLESTEP);
ptrace_disable(child);
wake_up_process(child);
break;
case PTRACE_SINGLESTEP: /* set the trap flag. */
#ifndef CONFIG_MN10300_USING_JTAG
ret = -EIO;
if ((unsigned long) data > _NSIG)
break;
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
ptrace_enable(child);
child->exit_code = data;
wake_up_process(child);
ret = 0;
#else
ret = -EINVAL;
#endif
break;
case PTRACE_DETACH: /* detach a process that was attached. */
ret = ptrace_detach(child, data);
break;
/* Get all gp regs from the child. */
case PTRACE_GETREGS: {
unsigned long tmp;
if (!access_ok(VERIFY_WRITE, (unsigned *) data, NR_PTREGS << 2)) {
ret = -EIO;
break;
}
for (i = 0; i < NR_PTREGS << 2; i += 4) {
tmp = get_stack_long(child, ptrace_regid_to_frame[i]);
__put_user(tmp, (unsigned long *) data);
data += sizeof(tmp);
}
ret = 0;
break;
}
case PTRACE_SETREGS: { /* Set all gp regs in the child. */
unsigned long tmp;
if (!access_ok(VERIFY_READ, (unsigned long *)data,
sizeof(struct pt_regs))) {
ret = -EIO;
break;
}
for (i = 0; i < NR_PTREGS << 2; i += 4) {
__get_user(tmp, (unsigned long *) data);
put_stack_long(child, ptrace_regid_to_frame[i], tmp);
data += sizeof(tmp);
}
ret = 0;
break;
}
case PTRACE_GETFPREGS: { /* Get the child FPU state. */
if (is_using_fpu(child)) {
unlazy_fpu(child);
fpu_state = child->thread.fpu_state;
} else {
memset(&fpu_state, 0, sizeof(fpu_state));
}
ret = -EIO;
if (copy_to_user((void *) data, &fpu_state,
sizeof(fpu_state)) == 0)
ret = 0;
break;
}
case PTRACE_SETFPREGS: { /* Set the child FPU state. */
ret = -EFAULT;
if (copy_from_user(&fpu_state, (const void *) data,
sizeof(fpu_state)) == 0) {
fpu_kill_state(child);
child->thread.fpu_state = fpu_state;
set_using_fpu(child);
ret = 0;
}
break;
}
case PTRACE_SETOPTIONS: {
if (data & PTRACE_O_TRACESYSGOOD)
child->ptrace |= PT_TRACESYSGOOD;
else
child->ptrace &= ~PT_TRACESYSGOOD;
ret = 0;
break;
}
default:
ret = -EIO;
break;
}
return ret;
}
/*
* notification of system call entry/exit
* - triggered by current->work.syscall_trace
*/
asmlinkage void do_syscall_trace(struct pt_regs *regs, int entryexit)
{
#if 0
/* just in case... */
printk(KERN_DEBUG "[%d] syscall_%lu(%lx,%lx,%lx,%lx) = %lx\n",
current->pid,
regs->orig_d0,
regs->a0,
regs->d1,
regs->a3,
regs->a2,
regs->d0);
return;
#endif
if (!test_thread_flag(TIF_SYSCALL_TRACE) &&
!test_thread_flag(TIF_SINGLESTEP))
return;
if (!(current->ptrace & PT_PTRACED))
return;
/* the 0x80 provides a way for the tracing parent to distinguish
between a syscall stop and SIGTRAP delivery */
ptrace_notify(SIGTRAP |
((current->ptrace & PT_TRACESYSGOOD) &&
!test_thread_flag(TIF_SINGLESTEP) ? 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;
}
}
