btrfs: Remove unused next_root_backup function

	return backup_index;

}

/*

 * this copies info out of the root backup array and back into

 * the in-memory super block.  It is meant to help iterate through

 * the array, so you send it the number of backups you've already

 * tried and the last backup index you used.

 *

 * this returns -1 when it has tried all the backups

 */

static noinline int next_root_backup(struct btrfs_fs_info *info,

				     struct btrfs_super_block *super,

				     int *num_backups_tried, int *backup_index)

{

	struct btrfs_root_backup *root_backup;

	int newest = *backup_index;

	if (*num_backups_tried == 0) {

		newest = find_newest_super_backup(info);

		if (newest == -1)

			return -1;

		*backup_index = newest;

		*num_backups_tried = 1;

	} else if (*num_backups_tried == BTRFS_NUM_BACKUP_ROOTS) {

		/* we've tried all the backups, all done */

		return -1;

	} else {

		/* jump to the next oldest backup */

		newest = (*backup_index + BTRFS_NUM_BACKUP_ROOTS - 1) %

			BTRFS_NUM_BACKUP_ROOTS;

		*backup_index = newest;

		*num_backups_tried += 1;

	}

	root_backup = super->super_roots + newest;

	btrfs_set_super_generation(super,

				   btrfs_backup_tree_root_gen(root_backup));

	btrfs_set_super_root(super, btrfs_backup_tree_root(root_backup));

	btrfs_set_super_root_level(super,

				   btrfs_backup_tree_root_level(root_backup));

	btrfs_set_super_bytes_used(super, btrfs_backup_bytes_used(root_backup));

	/*

	 * fixme: the total bytes and num_devices need to match or we should

	 * need a fsck

	 */

	btrfs_set_super_total_bytes(super, btrfs_backup_total_bytes(root_backup));

	btrfs_set_super_num_devices(super, btrfs_backup_num_devices(root_backup));

	return 0;

}

/* helper to cleanup workers */

static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)

{