ptrace.c

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/*
 *  linux/arch/h8300/kernel/ptrace.c
 *
 *  Yoshinori Sato <[email protected]>
 *
 *  Based on:
 *  linux/arch/m68k/kernel/ptrace.c
 *
 *  Copyright (C) 1994 by Hamish Macdonald
 *  Taken from linux/kernel/ptrace.c and modified for M680x0.
 *  linux/kernel/ptrace.c is by Ross Biro 1/23/92, edited by Linus Torvalds
 *
 * 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/sched.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/user.h>
#include <linux/signal.h>

#include <asm/uaccess.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/processor.h>
#include <asm/signal.h>

/* cpu depend functions */
extern long h8300_get_reg(struct task_struct *task, int regno);
extern int  h8300_put_reg(struct task_struct *task, int regno, unsigned long data);


void user_disable_single_step(struct task_struct *child)
{
}

/*
 * does not yet catch signals sent when the child dies.
 * in exit.c or in signal.c.
 */

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;
    int regno = addr >> 2;
    unsigned long __user *datap = (unsigned long __user *) data;

    switch (request) {
    /* read the word at location addr in the USER area. */
        case PTRACE_PEEKUSR: {
            unsigned long tmp = 0;
            
            if ((addr & 3) || addr >= sizeof(struct user)) {
                ret = -EIO;
                break ;
            }
            
                ret = 0;  /* Default return condition */

            if (regno < H8300_REGS_NO)
                tmp = h8300_get_reg(child, regno);
            else {
                switch (regno) {
                case 49:
                    tmp = child->mm->start_code;
                    break ;
                case 50:
                    tmp = child->mm->start_data;
                    break ;
                case 51:
                    tmp = child->mm->end_code;
                    break ;
                case 52:
                    tmp = child->mm->end_data;
                    break ;
                default:
                    ret = -EIO;
                }
            }
            if (!ret)
                ret = put_user(tmp, datap);
            break ;
        }

      /* when I and D space are separate, this will have to be fixed. */
        case PTRACE_POKEUSR: /* write the word at location addr in the USER area */
            if ((addr & 3) || addr >= sizeof(struct user)) {
                ret = -EIO;
                break ;
            }
                
            if (regno == PT_ORIG_ER0) {
                ret = -EIO;
                break ;
            }
            if (regno < H8300_REGS_NO) {
                ret = h8300_put_reg(child, regno, data);
                break ;
            }
            ret = -EIO;
            break ;

        case PTRACE_GETREGS: { /* Get all gp regs from the child. */
            int i;
            unsigned long tmp;
            for (i = 0; i < H8300_REGS_NO; i++) {
                tmp = h8300_get_reg(child, i);
                if (put_user(tmp, datap)) {
                ret = -EFAULT;
                break;
                }
                datap++;
            }
            ret = 0;
            break;
        }

        case PTRACE_SETREGS: { /* Set all gp regs in the child. */
            int i;
            unsigned long tmp;
            for (i = 0; i < H8300_REGS_NO; i++) {
                if (get_user(tmp, datap)) {
                ret = -EFAULT;
                break;
                }
                h8300_put_reg(child, i, tmp);
                datap++;
            }
            ret = 0;
            break;
        }

        default:
            ret = ptrace_request(child, request, addr, data);
            break;
    }
    return ret;
}

asmlinkage void do_syscall_trace(void)
{
    if (!test_thread_flag(TIF_SYSCALL_TRACE))
        return;
    if (!(current->ptrace & PT_PTRACED))
        return;
    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;
    }
}