dm: don't pass bio to __dm_start_io_acct and dm_end_io_acct

dm->orig_bio is always passed to __dm_start_io_acct and dm_end_io_acct,
so it isn't necessary to take one bio parameter for the two helpers.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>

drivers/md/dm.c

@@ -531,16 +531,13 @@ static void dm_io_acct(bool end, struct mapped_device *md, struct bio *bio,
 		bio->bi_iter.bi_size = bi_size;
 }
 
-static void __dm_start_io_acct(struct dm_io *io, struct bio *bio)
+static void __dm_start_io_acct(struct dm_io *io)
 {
-	dm_io_acct(false, io->md, bio, io->start_time, &io->stats_aux);
+	dm_io_acct(false, io->md, io->orig_bio, io->start_time, &io->stats_aux);
 }
 
 static void dm_start_io_acct(struct dm_io *io, struct bio *clone)
 {
-	/* Must account IO to DM device in terms of orig_bio */
-	struct bio *bio = io->orig_bio;
-
 	/*
 	 * Ensure IO accounting is only ever started once.
 	 */
@@ -558,12 +555,12 @@ static void dm_start_io_acct(struct dm_io *io, struct bio *clone)
 		spin_unlock_irqrestore(&io->lock, flags);
 	}
 
-	__dm_start_io_acct(io, bio);
+	__dm_start_io_acct(io);
 }
 
-static void dm_end_io_acct(struct dm_io *io, struct bio *bio)
+static void dm_end_io_acct(struct dm_io *io)
 {
-	dm_io_acct(true, io->md, bio, io->start_time, &io->stats_aux);
+	dm_io_acct(true, io->md, io->orig_bio, io->start_time, &io->stats_aux);
 }
 
 static struct dm_io *alloc_io(struct mapped_device *md, struct bio *bio)
@@ -899,14 +896,14 @@ static void dm_io_complete(struct dm_io *io)
 
 	io_error = io->status;
 	if (dm_io_flagged(io, DM_IO_ACCOUNTED))
-		dm_end_io_acct(io, bio);
+		dm_end_io_acct(io);
 	else if (!io_error) {
 		/*
 		 * Must handle target that DM_MAPIO_SUBMITTED only to
 		 * then bio_endio() rather than dm_submit_bio_remap()
 		 */
-		__dm_start_io_acct(io, bio);
-		dm_end_io_acct(io, bio);
+		__dm_start_io_acct(io);
+		dm_end_io_acct(io);
 	}
 	free_io(io);
 	smp_wmb();