It's 2017 now and I'm still using a Jolla 1 phone.

My BTRFS partition got corruption.
(One log entry causes the kernel to segfault while trying to replay).

I made the mistake of trying the recovery mode without much checking.
I ended up with a partition with cleared checksum, that still doesn't mount in-kernel (Still the same replay-log segfault).

Luckily, I can recover nearly every file I need from my busted partition (thank you BTRFS's Copy-on-Write !!!) using btrfs tools which will use whichever copy happens to not be busted.

Now instead of trying to rebuild a functioning BTRFS partition myself....
(which would be possible at this point but tedious - recovery mode lost the checksums, btrfs tools doesn't save the posix access rights, and I still need to fix the segfault causing log entry. So quite some work until phone is up again)
...I wanted to know if anyone happens to have a useable "factory-@" Image file ?

(Jolla Care are slow to answer my Zendesk ticket, and as mentioned above, it's not possible to publish it on web due to copyrighted bit from Qualcomm)