blob: a11db009d0ea0d907e41a089eaac9157cd87bf51 [file] [log] [blame]
/*
* linux/arch/h8300/kernel/ptrace.c
*
* Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
*
* 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/errno.h>
#include <linux/ptrace.h>
#include <linux/audit.h>
#include <linux/tracehook.h>
#include <linux/regset.h>
#include <linux/elf.h>
#define CCR_MASK 0x6f /* mode/imask not set */
#define EXR_MASK 0x80 /* modify only T */
#define PT_REG(r) offsetof(struct pt_regs, r)
extern void user_disable_single_step(struct task_struct *child);
/* 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 const int register_offset[] = {
PT_REG(er1), PT_REG(er2), PT_REG(er3), PT_REG(er4),
PT_REG(er5), PT_REG(er6), PT_REG(er0), -1,
PT_REG(orig_er0), PT_REG(ccr), PT_REG(pc),
#if defined(CONFIG_CPU_H8S)
PT_REG(exr),
#endif
};
/* read register */
long h8300_get_reg(struct task_struct *task, int regno)
{
switch (regno) {
case PT_USP:
return task->thread.usp + sizeof(long)*2;
case PT_CCR:
case PT_EXR:
return *(unsigned short *)(task->thread.esp0 +
register_offset[regno]);
default:
return *(unsigned long *)(task->thread.esp0 +
register_offset[regno]);
}
}
int h8300_put_reg(struct task_struct *task, int regno, unsigned long data)
{
unsigned short oldccr;
unsigned short oldexr;
switch (regno) {
case PT_USP:
task->thread.usp = data - sizeof(long)*2;
case PT_CCR:
oldccr = *(unsigned short *)(task->thread.esp0 +
register_offset[regno]);
oldccr &= ~CCR_MASK;
data &= CCR_MASK;
data |= oldccr;
*(unsigned short *)(task->thread.esp0 +
register_offset[regno]) = data;
break;
case PT_EXR:
oldexr = *(unsigned short *)(task->thread.esp0 +
register_offset[regno]);
oldccr &= ~EXR_MASK;
data &= EXR_MASK;
data |= oldexr;
*(unsigned short *)(task->thread.esp0 +
register_offset[regno]) = data;
break;
default:
*(unsigned long *)(task->thread.esp0 +
register_offset[regno]) = data;
break;
}
return 0;
}
static int regs_get(struct task_struct *target,
const struct user_regset *regset,
struct membuf to)
{
int r;
BUILD_BUG_ON(sizeof(struct user_regs_struct) % sizeof(long) != 0);
for (r = 0; r < ELF_NGREG; r++)
membuf_store(&to, h8300_get_reg(target, r));
return 0;
}
static int regs_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
int r;
int ret;
struct user_regs_struct regs;
long *reg;
/* build user regs in buffer */
BUILD_BUG_ON(sizeof(regs) % sizeof(long) != 0);
for (reg = (long *)&regs, r = 0; r < sizeof(regs) / sizeof(long); r++)
*reg++ = h8300_get_reg(target, r);
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&regs, 0, sizeof(regs));
if (ret)
return ret;
/* write back to pt_regs */
for (reg = (long *)&regs, r = 0; r < sizeof(regs) / sizeof(long); r++)
h8300_put_reg(target, r, *reg++);
return 0;
}
enum h8300_regset {
REGSET_GENERAL,
};
static const struct user_regset h8300_regsets[] = {
[REGSET_GENERAL] = {
.core_note_type = NT_PRSTATUS,
.n = ELF_NGREG,
.size = sizeof(long),
.align = sizeof(long),
.regset_get = regs_get,
.set = regs_set,
},
};
static const struct user_regset_view user_h8300_native_view = {
.name = "h8300",
.e_machine = EM_H8_300,
.regsets = h8300_regsets,
.n = ARRAY_SIZE(h8300_regsets),
};
const struct user_regset_view *task_user_regset_view(struct task_struct *task)
{
return &user_h8300_native_view;
}
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;
switch (request) {
default:
ret = ptrace_request(child, request, addr, data);
break;
}
return ret;
}
asmlinkage long do_syscall_trace_enter(struct pt_regs *regs)
{
long ret = 0;
if (test_thread_flag(TIF_SYSCALL_TRACE) &&
tracehook_report_syscall_entry(regs))
/*
* Tracing decided this syscall should not happen.
* We'll return a bogus call number to get an ENOSYS
* error, but leave the original number in regs->regs[0].
*/
ret = -1L;
audit_syscall_entry(regs->er1, regs->er2, regs->er3,
regs->er4, regs->er5);
return ret ?: regs->er0;
}
asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
{
int step;
audit_syscall_exit(regs);
step = test_thread_flag(TIF_SINGLESTEP);
if (step || test_thread_flag(TIF_SYSCALL_TRACE))
tracehook_report_syscall_exit(regs, step);
}