/*
 * Wait on and process all in-flight BIOs.  This must only be called once
 * all bios have been issued so that the refcount can only decrease.
 * This just waits for all bios to make it through dio_bio_complete.  IO
 * errors are propagated through dio->io_error and should be propagated via
 * dio_complete().
 */
static void dio_await_completion(struct dio *dio)
{
        struct bio *bio;
        do {
                bio = dio_await_one(dio);
                if (bio)
                        dio_bio_complete(dio, bio);
        } while (bio);
}