From ee8289a2953c2d345c7d56f77e93edc18f4b7ad9 Mon Sep 17 00:00:00 2001
From: Josh Boyer <jwboyer@fedoraproject.org>
Date: Fri, 31 Jul 2015 15:26:05 -0400
Subject: [PATCH] Revert "dm: fix casting bug in dm_merge_bvec()"

This reverts commit 1c220c69ce0dcc0f234a9f263ad9c0864f971852.
---
 drivers/md/dm.c | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index ab37ae114e94..bd5ad54919ab 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1729,7 +1729,8 @@ static int dm_merge_bvec(struct request_queue *q,
 	struct mapped_device *md = q->queuedata;
 	struct dm_table *map = dm_get_live_table_fast(md);
 	struct dm_target *ti;
-	sector_t max_sectors, max_size = 0;
+	sector_t max_sectors;
+	int max_size = 0;
 
 	if (unlikely(!map))
 		goto out;
@@ -1744,16 +1745,8 @@ static int dm_merge_bvec(struct request_queue *q,
 	max_sectors = min(max_io_len(bvm->bi_sector, ti),
 			  (sector_t) queue_max_sectors(q));
 	max_size = (max_sectors << SECTOR_SHIFT) - bvm->bi_size;
-
-	/*
-	 * FIXME: this stop-gap fix _must_ be cleaned up (by passing a sector_t
-	 * to the targets' merge function since it holds sectors not bytes).
-	 * Just doing this as an interim fix for stable@ because the more
-	 * comprehensive cleanup of switching to sector_t will impact every
-	 * DM target that implements a ->merge hook.
-	 */
-	if (max_size > INT_MAX)
-		max_size = INT_MAX;
+	if (unlikely(max_size < 0)) /* this shouldn't _ever_ happen */
+		max_size = 0;
 
 	/*
 	 * merge_bvec_fn() returns number of bytes
@@ -1761,7 +1754,7 @@ static int dm_merge_bvec(struct request_queue *q,
 	 * max is precomputed maximal io size
 	 */
 	if (max_size && ti->type->merge)
-		max_size = ti->type->merge(ti, bvm, biovec, (int) max_size);
+		max_size = ti->type->merge(ti, bvm, biovec, max_size);
 	/*
 	 * If the target doesn't support merge method and some of the devices
 	 * provided their merge_bvec method (we know this by looking for the
-- 
2.4.3