Drop 'size' argument from bio_endio and bi_end_io

As bi_end_io is only called once when the reqeust is complete,
the 'size' argument is now redundant.  Remove it.

Now there is no need for bio_endio to subtract the size completed
from bi_size.  So don't do that either.

While we are at it, change bi_end_io to return void.

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 1e2af43..f2a63f3 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -82,21 +82,17 @@
 	struct bio *bio = mp_bh->master_bio;
 	multipath_conf_t *conf = mddev_to_conf(mp_bh->mddev);
 
-	bio_endio(bio, bio->bi_size, err);
+	bio_endio(bio, err);
 	mempool_free(mp_bh, conf->pool);
 }
 
-static int multipath_end_request(struct bio *bio, unsigned int bytes_done,
-				 int error)
+static void multipath_end_request(struct bio *bio, int error)
 {
 	int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
 	struct multipath_bh * mp_bh = (struct multipath_bh *)(bio->bi_private);
 	multipath_conf_t *conf = mddev_to_conf(mp_bh->mddev);
 	mdk_rdev_t *rdev = conf->multipaths[mp_bh->path].rdev;
 
-	if (bio->bi_size)
-		return 1;
-
 	if (uptodate)
 		multipath_end_bh_io(mp_bh, 0);
 	else if (!bio_rw_ahead(bio)) {
@@ -112,7 +108,6 @@
 	} else
 		multipath_end_bh_io(mp_bh, error);
 	rdev_dec_pending(rdev, conf->mddev);
-	return 0;
 }
 
 static void unplug_slaves(mddev_t *mddev)
@@ -155,7 +150,7 @@
 	const int rw = bio_data_dir(bio);
 
 	if (unlikely(bio_barrier(bio))) {
-		bio_endio(bio, bio->bi_size, -EOPNOTSUPP);
+		bio_endio(bio, -EOPNOTSUPP);
 		return 0;
 	}
 
@@ -169,7 +164,7 @@
 
 	mp_bh->path = multipath_map(conf);
 	if (mp_bh->path < 0) {
-		bio_endio(bio, bio->bi_size, -EIO);
+		bio_endio(bio, -EIO);
 		mempool_free(mp_bh, conf->pool);
 		return 0;
 	}