path: root/kernel/compat.c

/*
 *  linux/kernel/compat.c
 *
 *  Kernel compatibililty routines for e.g. 32 bit syscall support
 *  on 64 bit kernels.
 *
 *  Copyright (C) 2002-2003 Stephen Rothwell, IBM Corporation
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 */

#include <linux/linkage.h>
#include <linux/compat.h>
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/signal.h>
#include <linux/sched.h>	/* for MAX_SCHEDULE_TIMEOUT */
#include <linux/syscalls.h>
#include <linux/unistd.h>
#include <linux/security.h>
#include <linux/timex.h>
#include <linux/migrate.h>
#include <linux/posix-timers.h>
#include <linux/times.h>
#include <linux/ptrace.h>

#include <asm/uaccess.h>

/*
 * Note that the native side is already converted to a timespec, because
 * that's what we want anyway.
 */
static int compat_get_timeval(struct timespec *o,
		struct compat_timeval __user *i)
{
	long usec;

	if (get_user(o->tv_sec, &i->tv_sec) ||
	    get_user(usec, &i->tv_usec))
		return -EFAULT;
	o->tv_nsec = usec * 1000;
	return 0;
}

static int compat_put_timeval(struct compat_timeval __user *o,
		struct timeval *i)
{
	return (put_user(i->tv_sec, &o->tv_sec) ||
		put_user(i->tv_usec, &o->tv_usec)) ? -EFAULT : 0;
}

asmlinkage long compat_sys_gettimeofday(struct compat_timeval __user *tv,
		struct timezone __user *tz)
{
	if (tv) {
		struct timeval ktv;
		do_gettimeofday(&ktv);
		if (compat_put_timeval(tv, &ktv))
			return -EFAULT;
	}
	if (tz) {
		if (copy_to_user(tz, &sys_tz, sizeof(sys_tz)))
			return -EFAULT;
	}

	return 0;
}

asmlinkage long compat_sys_settimeofday(struct compat_timeval __user *tv,
		struct timezone __user *tz)
{
	struct timespec kts;
	struct timezone ktz;

	if (tv) {
		if (compat_get_timeval(&kts, tv))
			return -EFAULT;
	}
	if (tz) {
		if (copy_from_user(&ktz, tz, sizeof(ktz)))
			return -EFAULT;
	}

	return do_sys_settimeofday(tv ? &kts : NULL, tz ? &ktz : NULL);
}

int get_compat_timespec(struct timespec *ts, const struct compat_timespec __user *cts)
{
	return (!access_ok(VERIFY_READ, cts, sizeof(*cts)) ||
			__get_user(ts->tv_sec, &cts->tv_sec) ||
			__get_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
}

int put_compat_timespec(const struct timespec *ts, struct compat_timespec __user *cts)
{
	return (!access_ok(VERIFY_WRITE, cts, sizeof(*cts)) ||
			__put_user(ts->tv_sec, &cts->tv_sec) ||
			__put_user(ts->tv_nsec, &cts->tv_nsec)) ? -EFAULT : 0;
}

static long compat_nanosleep_restart(struct restart_block *restart)
{
	struct compat_timespec __user *rmtp;
	struct timespec rmt;
	mm_segment_t oldfs;
	long ret;

	restart->nanosleep.rmtp