[Btrfs-devel] 2.6.29-rc1: Cannot loopback mount btrfs formatted file

[Christian Hesse]

On Sunday 11 January 2009, Peter Klotz wrote:
> Since 2.6.29-rc1 contains btrfs I had to try it.
>
> However the loopback mount of my btrfs formatted file fails:
>
> user at host:~$ dd if=/dev/zero of=btrfs.img bs=1MB count=512
>
> user at host:~$ mkfs.btrfs btrfs.img
> fs created label (null) on btrfs.img
>      nodesize 4096 leafsize 4096 sectorsize 4096 size 488.28MB
> Btrfs v0.16+da35ab2b0b54
>
> user at host:~$ sudo mount -t btrfs -o loop btrfs.img /mnt/btrfs
> mount: /dev/loop1: can't read superblock
>
>
> Is this version of mkfs.btrfs compatible with the kernel module in
> 2.6.29-rc1?

You have to use the btrfs-progs from unstable git repository. Chris plans to 
release a new stable version within one day though.
-- 
Regards,
Chris