1 #val_type uint64_t 2 BTRFS_ROOT_TREE_OBJECTID 1ULL 3 BTRFS_EXTENT_TREE_OBJECTID 2ULL 4 BTRFS_CHUNK_TREE_OBJECTID 3ULL 5 BTRFS_DEV_TREE_OBJECTID 4ULL 6 BTRFS_FS_TREE_OBJECTID 5ULL 7 BTRFS_ROOT_TREE_DIR_OBJECTID 6ULL 8 BTRFS_CSUM_TREE_OBJECTID 7ULL 9 BTRFS_QUOTA_TREE_OBJECTID 8ULL 10 BTRFS_UUID_TREE_OBJECTID 9ULL 11 BTRFS_FREE_SPACE_TREE_OBJECTID 10ULL 12 BTRFS_FIRST_FREE_OBJECTID 256ULL 13 BTRFS_LAST_FREE_OBJECTID -256ULL 14 UINT64_MAX -1ULL 15
