backup_root_index 866 fs/btrfs/ctree.h int backup_root_index; backup_root_index 1829 fs/btrfs/disk-io.c info->backup_root_index = 0; backup_root_index 1831 fs/btrfs/disk-io.c info->backup_root_index = (newest_index + 1) % BTRFS_NUM_BACKUP_ROOTS; backup_root_index 1846 fs/btrfs/disk-io.c next_backup = info->backup_root_index; backup_root_index 1867 fs/btrfs/disk-io.c info->backup_root_index = (next_backup + 1) % BTRFS_NUM_BACKUP_ROOTS;