openSUSE/snapper — pull request #4 by oniko (2012-12-05 09:58:24+00:00)
Title: - report failed ioctls in clonefile() as warning only

On thin-provisioned volumes, this will cause an error message for each file that is supposed to be created during 'undochange' command. I was thinking about possible general fix (i.e. get info about underlying filesystem, if it's != btrfs then...), but in the end this looks to me as an easiest solution for now.
I don't know how big is the issue when clonefile() possibly fails on btrfs...