Fixes

This serie fixes various problems, of which only the first commit fixes a possible crash/data corruption with btrfs. I have only check the file updated by the commit c255342 and did not look further in the btrfs's history. I am searching why the test for exfat is failing since 35e201c.

I am not 100% sure we should ignore all the .in I added to .gitignore. You should double-check this one.