How to recover data from an xfs partition

[Niccolò Belli]

Hi,
I had a (software) problem with my xen server ended ruining my domU 
partitions. I already recovered all my ext4 partitions using fsck.ext4, 
but I can't recover the only xfs partition I have :(

When I try to mount I get:

root at firewall:~# mount -o loop,offset=$((97280*1024)) -t xfs 
/srv/xen/webserver.img /mnt
mount: Structure needs cleaning



While when trying to fsck I get:

root at firewall:~# xfs_check /dev/loop51
xfs_check: /dev/loop51 is not a valid XFS filesystem (unexpected SB 
magic number 0xeb639010)
xfs_check: size check failed
xfs_check: WARNING - filesystem uses v1 dirs,limited functionality provided.
cache_node_purge: refcount was 1, not zero (node=0x11f0820)
xfs_check: cannot read root inode (22)
cache_node_purge: refcount was 1, not zero (node=0x11f0970)
xfs_check: cannot read realtime bitmap inode (22)
xfs_check: size check failed
xfs_check: WARNING - filesystem uses v1 dirs,limited functionality provided.
bad superblock magic number eb639010, giving up



xfs_check:

root at firewall:~# xfs_check /dev/loop51
xfs_check: /dev/loop51 is not a valid XFS filesystem (unexpected SB 
magic number 0xeb639010)
xfs_check: size check failed
xfs_check: WARNING - filesystem uses v1 dirs,limited functionality provided.
cache_node_purge: refcount was 1, not zero (node=0x22f1820)
xfs_check: cannot read root inode (22)
cache_node_purge: refcount was 1, not zero (node=0x22f1970)
xfs_check: cannot read realtime bitmap inode (22)
xfs_check: size check failed
xfs_check: WARNING - filesystem uses v1 dirs,limited functionality provided.
bad superblock magic number eb639010, giving up




xfs_repair:

root at firewall:~# xfs_repair /dev/loop51
Phase 1 - find and verify superblock...
bad primary superblock - bad magic number !!!

attempting to find secondary superblock...
................................................................................found 
candidate secondary superblock...
unable to verify superblock, continuing...
.............
[...]
....................................Sorry, could not find valid 
secondary superblock
Exiting now.


How can I restore my data? I cannot believe I had no problems restoring 
*15* ext4 partitions while I can't restore the only xfs partition I have :(

Hope you can help,
Niccolò