/*
* arch/score/kernel/ptrace.c
*
* Score Processor version.
*
* Copyright (C) 2009 Sunplus Core Technology Co., Ltd.
* Chen Liqin <liqin.chen@sunplusct.com>
* Lennox Wu <lennox.wu@sunplusct.com>
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see the file COPYING, or write
* to the Free Software Foundation, Inc.,
* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <linux/kernel.h>
#include <linux/ptrace.h>
#include <asm/uaccess.h>
static int is_16bitinsn(unsigned long insn)
{
if ((insn & INSN32_MASK) == INSN32_MASK)
return 0;
else
return 1;
}
int
read_tsk_long(struct task_struct *child,
unsigned long addr, unsigned long *res)
{
int copied;
copied = access_process_vm(child, addr, res, sizeof(*res), 0);
return copied != sizeof(*res) ? -EIO : 0;
}
int
read_tsk_short(struct task_struct *child,
unsigned long addr, unsigned short *res)
{
int copied;
copied = access_process_vm(child, addr, res, sizeof(*res), 0);
return copied != sizeof(*res) ? -EIO : 0;
}
static int
write_tsk_short(struct task_struct *child,
unsigned long addr, unsigned short val)
{
int copied;
copied = access_process_vm(child, addr, &val, sizeof(val), 1);
return copied != sizeof(val) ? -EIO : 0;
}
static int
write_tsk_long(struct task_struct *child,
unsigned long addr, unsigned long val)
{
int copied;
copied = access_process_vm(child, addr, &val, sizeof(val), 1);
return copied != sizeof(val) ? -EIO : 0;
}
/*
* Get all user integer registers.
*/
static int ptrace_getregs(struct task_struct *tsk, void __user *uregs)
{
struct pt_regs *regs = task_pt_regs(tsk);
return copy_to_user(uregs, regs, sizeof(struct pt_regs)) ? -EFAULT : 0;
}
/*
* Set all user integer registers.
*/
static int ptrace_setregs(struct task_struct *tsk, void __user *uregs)
{
struct pt_regs newregs;
int ret;
ret = -EFAULT;
if (copy_from_user(&newregs, uregs, sizeof(struct pt_regs)) == 0) {
struct pt_regs *regs = task_pt_regs(tsk);
*regs = newregs;
ret = 0;
}
return ret;
}
void user_enable_single_step(struct task_struct *child)
{
/* far_epc is the target of branch */
unsigned int epc, far_epc = 0;
unsigned long epc_insn, far_epc_insn;
int ninsn_type; /* next insn type 0=16b, 1=32b */
unsigned int tmp, tmp2;
struct pt_regs *regs = task_pt_regs(child);
child->thread.single_step = 1;
child->thread.ss_nextcnt = 1;
epc = regs->cp0_epc;
read_tsk_long(child, epc, &epc_insn);
if (is_16bitinsn(epc_insn)) {
if ((epc_insn & J16M) == J16) {
tmp = epc_insn & 0xFFE;
epc = (epc & 0xFFFFF000) | tmp;
} else if ((epc_insn & B16M) == B16) {
child->thread.ss_nextcnt = 2;
tmp = (epc_insn & 0xFF) << 1;
tmp = tmp << 23;
tmp = (unsigned int)((int) tmp >> 23);
far_epc = epc + tmp;
epc += 2;
} else if ((epc_insn & BR16M) == BR16) {
child->thread.ss_nextcnt = 2;
tmp = (epc_insn >> 4) & 0xF;
far_epc = regs->regs[tmp];
epc += 2;
} else
epc += 2;
} else {
if ((epc_insn & J32M) == J32) {
tmp = epc_insn & 0x03FFFFFE;
tmp2 = tmp & 0x7FFF;
tmp = (((tmp >> 16) & 0x3FF) << 15) | tmp2;
epc = (epc & 0xFFC00000) | tmp;
} else if ((epc_insn & B32M) == B32) {
child->thread.ss_nextcnt = 2;
tmp = epc_insn & 0x03FFFFFE; /* discard LK bit */
tmp2 = tmp & 0x3FF;
tmp = (((tmp >> 16) & 0x3FF) << 10) | tmp2; /* 20bit */
tmp = tmp << 12;
tmp = (unsigned int)((int) tmp >> 12);
far_epc = epc + tmp;
epc += 4;
} else if ((epc_insn & BR32M) == BR32) {
child->thread.ss_nextcnt = 2;
tmp = (epc_insn >> 16) & 0x1F;
far_epc = regs->regs[tmp];
epc += 4;
} else
epc += 4;
}
if (child->thread.ss_nextcnt == 1) {
read_tsk_long(child, epc, &epc_insn);
if (is_16bitinsn(epc_insn)) {
write_tsk_short(child, epc, SINGLESTEP16_INSN);
ninsn_type = 0;
} else {
write_tsk_long(child, epc, SINGLESTEP32_INSN);
ninsn_type = 1;
}
if (ninsn_type == 0) { /* 16bits */
child->thread.insn1_type = 0;
child->thread.addr1 = epc;
/* the insn may have 32bit data */
child->thread.insn1 = (short)epc_insn;
} else {
child->thread.insn1_type = 1;
child->thread.addr1 = epc;
child->thread.insn1 = epc_insn;
}
} else {
/* branch! have two target child->thread.ss_nextcnt=2 */
read_tsk_long(child, epc, &epc_insn);
read_tsk_long(child, far_epc, &far_epc_insn);
if (is_16bitinsn(epc_insn)) {
write_tsk_short(child, epc, SINGLESTEP16_INSN);
ninsn_type = 0;
} else {
write_tsk_long(child, epc, SINGLESTEP32_INSN);
ninsn_type = 1;
}
if (ninsn_type == 0) { /* 16bits */
child->thread.insn1_type = 0;
child->thread.addr1 = epc;
/* the insn may have 32bit data */
child->thread.insn1 = (short)epc_insn;
} else {
child->thread.insn1_type = 1;
child->thread.addr1 = epc;
child->thread.insn1 = epc_insn;
}
if (is_16bitinsn(far_epc_insn)) {
write_tsk_short(child, far_epc, SINGLESTEP16_INSN);
ninsn_type = 0;
} else {
write_tsk_long(child, far_epc, SINGLESTEP32_INSN);
ninsn_type = 1;
}
if (ninsn_type == 0) { /* 16bits */
child->thread.insn2_type = 0;
child->thread.addr2 = far_epc;
/* the insn may have 32bit data */
child->thread.insn2 = (short)far_epc_insn;
} else {
child->thread.insn2_type = 1;
child->thread.addr2 = far_epc;
child->thread.insn2 = far_epc_insn;
}
}
}
void user_disable_single_step(struct task_struct *child)
{
if (child->thread.insn1_type == 0)
write_tsk_short(child, child->thread.addr1,
child->thread.insn1);
if (child->thread.insn1_type == 1)
write_tsk_long(child, child->thread.addr1,
child->thread.insn1);
if (child->thread.ss_nextcnt == 2) { /* branch */
if (child->thread.insn1_type == 0)
write_tsk_short(child, child->thread.addr1,
child->thread.insn1);
if (child->thread.insn1_type == 1)
write_tsk_long(child, child->thread.addr1,
child->thread.insn1);
if (child->thread.insn2_type == 0)
write_tsk_short(child, child->thread.addr2,
child->thread.insn2);
if (child->thread.insn2_type == 1)
write_tsk_long(child, child->thread.addr2,
child->thread.insn2);
}
child->thread.single_step = 0;
child->thread.ss_nextcnt = 0;
}
void ptrace_disable(struct task_struct *child)
{
user_disable_single_step(child);
}
long
arch_ptrace(struct task_struct *child, long request, long addr, long data)
{
int ret;
switch (request) {
/* Read the word at location addr in the USER area. */
case PTRACE_PEEKUSR: {
struct pt_regs *regs;
unsigned long tmp;
regs = task_pt_regs(child);
tmp = 0; /* Default return value. */
switch (addr) {
case 0 ... 31:
tmp = regs->regs[addr];
break;
case PC:
tmp = regs->cp0_epc;
break;
case ECR:
tmp = regs->cp0_ecr;
break;
case EMA:
tmp = regs->cp0_ema;
break;
case CEH:
tmp = regs->ceh;
break;
case CEL:
tmp = regs->cel;
break;
case CONDITION:
tmp = regs->cp0_condition;
break;
case PSR:
tmp = regs->cp0_psr;
break;
case COUNTER:
tmp = regs->sr0;
break;
case LDCR:
tmp = regs->sr1;
break;
case STCR:
tmp = regs->sr2;
break;
default:
tmp = 0;
return -EIO;
}
ret = put_user(tmp, (unsigned long *) data);
return ret;
}
case PTRACE_POKEUSR: {
struct pt_regs *regs;
ret = 0;
regs = task_pt_regs(child);
switch (addr) {
case 0 ... 31:
regs->regs[addr] = data;
break;
case PC:
regs->cp0_epc = data;
break;
case CEH:
regs->ceh = data;
break;
case CEL:
regs->cel = data;
break;
case CONDITION:
regs->cp0_condition = data;
break;
case PSR:
case COUNTER:
case STCR:
case LDCR:
break; /* user can't write the reg */
default:
/* The rest are not allowed. */
ret = -EIO;
break;
}
break;
}
case PTRACE_GETREGS:
ret = ptrace_getregs(child, (void __user *)data);
break;
case PTRACE_SETREGS:
ret = ptrace_setregs(child, (void __user *)data);
break;
default:
ret = ptrace_request(child, request, addr, data);
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 (!(current->ptrace & PT_PTRACED))
return;
if (!test_thread_flag(TIF_SYSCALL_TRACE))
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;
}
}
