btrfs: defrag: make readahead state allocation failure non-fatal

All sorts of readahead errors are not considered fatal. We can continue
defragmentation without it, with some potential slow down, which will
last only for the current inode.

Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2017-06-22 03:22:58 +02:00
commit 0a52d10808