/*
* Copyright 2010 Tilera Corporation. All Rights Reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, version 2.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
* NON INFRINGEMENT. See the GNU General Public License for
* more details.
*
* Copied from i386: Ross Biro 1/23/92
*/
#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <linux/kprobes.h>
#include <linux/compat.h>
#include <linux/uaccess.h>
void user_enable_single_step(struct task_struct *child)
{
set_tsk_thread_flag(child, TIF_SINGLESTEP);
}
void user_disable_single_step(struct task_struct *child)
{
clear_tsk_thread_flag(child, TIF_SINGLESTEP);
}
/*
* This routine will put a word on the process's privileged stack.
*/
static void putreg(struct task_struct *task,
unsigned long addr, unsigned long value)
{
unsigned int regno = addr / sizeof(unsigned long);
struct pt_regs *childregs = task_pt_regs(task);
childregs->regs[regno] = value;
childregs->flags |= PT_FLAGS_RESTORE_REGS;
}
static unsigned long getreg(struct task_struct *task, unsigned long addr)
{
unsigned int regno = addr / sizeof(unsigned long);
struct pt_regs *childregs = task_pt_regs(task);
return childregs->regs[regno];
}
/*
* Called by kernel/ptrace.c when detaching..
*/
void ptrace_disable(struct task_struct *child)
{
clear_tsk_thread_flag(child, TIF_SINGLESTEP);
/*
* These two are currently unused, but will be set by arch_ptrace()
* and used in the syscall assembly when we do support them.
*/
clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
}
long arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
unsigned long __user *datap;
unsigned long tmp;
int i;
long ret = -EIO;
#ifdef CONFIG_COMPAT
if (task_thread_info(current)->status & TS_COMPAT)
data = (u32)data;
if (task_thread_info(child)->status & TS_COMPAT)
addr = (u32)addr;
#endif
datap = (unsigned long __user *)data;
switch (request) {
case PTRACE_PEEKUSR: /* Read register from pt_regs. */
if (addr & (sizeof(data)-1))
break;
if (addr < 0 || addr >= PTREGS_SIZE)
break;
tmp = getreg(child, addr); /* Read register */
ret = put_user(tmp, datap);
break;
case PTRACE_POKEUSR: /* Write register in pt_regs. */
if (addr & (sizeof(data)-1))
break;
if (addr < 0 || addr >= PTREGS_SIZE)
break;
putreg(child, addr, data); /* Write register */
break;
case PTRACE_GETREGS: /* Get all registers from the child. */
if (!access_ok(VERIFY_WRITE, datap, PTREGS_SIZE))
break;
for (i = 0; i < PTREGS_SIZE; i += sizeof(long)) {
ret = __put_user(getreg(child, i), datap);
if (ret != 0)
break;
datap++;
}
break;
case PTRACE_SETREGS: /* Set all registers in the child. */
if (!access_ok(VERIFY_READ, datap, PTREGS_SIZE))
break;
for (i = 0; i < PTREGS_SIZE; i += sizeof(long)) {
ret = __get_user(tmp, datap);
if (ret != 0)
break;
putreg(child, i, tmp);
datap++;
}
break;
case PTRACE_GETFPREGS: /* Get the child FPU state. */
case PTRACE_SETFPREGS: /* Set the child FPU state. */
break;
case PTRACE_SETOPTIONS:
/* Support TILE-specific ptrace options. */
child->ptrace &= ~PT_TRACE_MASK_TILE;
tmp = data & PTRACE_O_MASK_TILE;
data &= ~PTRACE_O_MASK_TILE;
ret = ptrace_request(child, request, addr, data);
if (tmp & PTRACE_O_TRACEMIGRATE)
child->ptrace |= PT_TRACE_MIGRATE;
break;
default:
#ifdef CONFIG_COMPAT
if (task_thread_info(current)->status & TS_COMPAT) {
ret = compat_ptrace_request(child, request,
addr, data);
break;
}
#endif
ret = ptrace_request(child, request, addr, data);
break;
}
return ret;
}
#ifdef CONFIG_COMPAT
/* Not used; we handle compat issues in arch_ptrace() directly. */
long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
compat_ulong_t addr, compat_ulong_t data)
{
BUG();
}
#endif
void do_syscall_trace(void)
{
if (!test_thread_flag(TIF_SYSCALL_TRACE))
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) ? 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;
}
}
void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code)
{
struct siginfo info;
memset(&info, 0, sizeof(info));
info.si_signo = SIGTRAP;
info.si_code = TRAP_BRKPT;
info.si_addr = (void __user *) regs->pc;
/* Send us the fakey SIGTRAP */
force_sig_info(SIGTRAP, &info, tsk);
}
/* Handle synthetic interrupt delivered only by the simulator. */
void __kprobes do_breakpoint(struct pt_regs* regs, int fault_num)
{
send_sigtrap(current, regs, fault_num);
}
