md: Simplify restart_array().

static int restart_array(mddev_t *mddev)

{

	struct gendisk *disk = mddev->gendisk;

	int err;

	/*

	 * Complain if it has no devices

	 */

	err = -ENXIO;

	/* Complain if it has no devices */

	if (list_empty(&mddev->disks))

		goto out;

	if (mddev->pers) {

		err = -EBUSY;

		return -ENXIO;

	if (!mddev->pers)

		return -EINVAL;

	if (!mddev->ro)

			goto out;

		return -EBUSY;

	mddev->safemode = 0;

	mddev->ro = 0;

	set_disk_ro(disk, 0);

	printk(KERN_INFO "md: %s switched to read-write mode.\n",

		mdname(mddev));

		/*

		 * Kick recovery or resync if necessary

		 */

	/* Kick recovery or resync if necessary */

	set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);

	md_wakeup_thread(mddev->thread);

	md_wakeup_thread(mddev->sync_thread);

		err = 0;

	sysfs_notify(&mddev->kobj, NULL, "array_state");

	} else

		err = -EINVAL;

out:

	return err;

	return 0;

}

/* similar to deny_write_access, but accounts for our holding a reference