BTRFS corrupted by combination of mistreatment of hiberantion and accidental power loss.

[Adam Ryczkowski <adam.ryczkowski@statystyka.net>]

I have two independent Linux installations my notebook, both sharing the 
same btrfs partition as root file system, but installed on different 
subvolumes.

I hibernated one Linux (Mint 15 64 bit). Hibernation data is stored on 
the swap file, which is used exclusively by this system.

Then 2 events happened.

1) I accidentally ran the other system, which wasn't hibernated - Ubuntu 
12.10. Realizing the problem, I waited until the system booted up, and 
then shutdowned it.

Then I opened the hibernated Mint 15. Restoration went successful, and I 
never thought I am in trouble.

2) Immediately after that, by coincidence, the battery fell down, 
brutally powering down the computer.

After that, I am unable to repair/mount the root btrfs partition, 
however I try (I built the current btrfs-tools from git). Dmesg displays 
only one error entry: btrfs: open_ctree failed.

I know, that if one those two events happened separately, there would be 
no problem. The problem arose only when those two events happened 
simultaneously.

So I guess I am experiencing one of the corner cases.

What are my prospects to restoring my data? I have several subvolumes on 
the hard drive, some of them were not touched by the accident at all.

Adam Ryczkowski