/*
* 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/elf.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/ptrace.h>
#include <linux/regset.h>
#include <asm/uaccess.h>
/*
* retrieve the contents of SCORE userspace general registers
*/
static int genregs_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
const struct pt_regs *regs = task_pt_regs(target);
int ret;
/* skip 9 * sizeof(unsigned long) not use for pt_regs */
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
0, offsetof(struct pt_regs, regs));
/* r0 - r31, cel, ceh, sr0, sr1, sr2, epc, ema, psr, ecr, condition */
ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
regs->regs,
offsetof(struct pt_regs, regs),
offsetof(struct pt_regs, cp0_condition));
if (!ret)
ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
sizeof(struct pt_regs), -1);
return ret;
}
/*
* update the contents of the SCORE userspace general registers
*/
static int genregs_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
struct pt_regs *regs = task_pt_regs(target);
int ret;
/* skip 9 * sizeof(unsigned long) */
ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
0, offsetof(struct pt_regs, regs));
/* r0 - r31, cel, ceh, sr0, sr1, sr2, epc, ema, psr, ecr, condition */
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
regs->regs,
offsetof(struct pt_regs, regs),
offsetof(struct pt_regs, cp0_condition));
if (!ret)
ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
sizeof(struct pt_regs), -1);
return ret;
}
/*
* Define the register sets available on the score7 under Linux
*/
enum score7_regset {
REGSET_GENERAL,
};
static const struct user_regset score7_regsets[] = {
[REGSET_GENERAL] = {
.core_note_type = NT_PRSTATUS,
.n = ELF_NGREG,
.size = sizeof(long),
.align = sizeof(long),
.get = genregs_get,
.set = genregs_set,
},
};
static const struct user_regset_view user_score_native_view = {
.name = "score7",
.e_machine = EM_SCORE7,
.regsets = score7_regsets,
.n = ARRAY_SIZE(score7_regsets),
};
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
return &user_score_native_view;
}
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;
}
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,
unsigned long addr, unsigned long data)
{
int ret;
unsigned long __user *datap = (void __user *)data;
switch (request) {
case PTRACE_GETREGS:
ret = copy_regset_to_user(child, &user_score_native_view,
REGSET_GENERAL,
0, sizeof(struct pt_regs),
datap);
break;
case PTRACE_SETREGS:
ret = copy_regset_from_user(child, &user_score_native_view,
REGSET_GENERAL,
0, sizeof(struct pt_regs),
datap);
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;
}
}