The block layer call chain from submit_bio will check if the write cache
is enabled for the given queue before submitting the flush. This will
add a code to fail fast if its not.
Signed-off-by: Anand Jain <anand.jain@oracle.com> Reviewed-by: David Sterba <dsterba@suse.com>
[ updated changelog to reflect current code stat, blkdev_issue_flush is
not used yet ] Signed-off-by: David Sterba <dsterba@suse.com>