Any idea how to add ext4fs support? I tried this patch http://old.nabble.com/-patch--ext4fs-read-only-mode-td29504369.html but the files don't match the kernel sources - /usr/src/sys/fs/ext2fs/ext2_alloc.c doesn't exist and /usr/src/sys/gnu/fs/ext2fs/ext2_alloc.c is too different.