btrfs: account that we're waiting for DIO read

Correctly account for IO when waiting for a submitted DIO read, the case
when we're retrying.  This only for the accounting purposes and should
not change other behaviour.

Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
David Sterba 2017-07-19 19:26:45 +02:00
commit 9c17f6cda1