-FILESYSTEMS = ext2 ext4 reiserfs iso9660 hfs
-FILESYSTEMS_GNUEFI = ext2_gnuefi ext4_gnuefi reiserfs_gnuefi iso9660_gnuefi hfs_gnuefi
+FILESYSTEMS = ext2 ext4 reiserfs iso9660 hfs btrfs
+FILESYSTEMS_GNUEFI = ext2_gnuefi ext4_gnuefi reiserfs_gnuefi iso9660_gnuefi hfs_gnuefi btrfs_gnuefi