From: Keith Busch <keith.busch@intel.com>
Date: Tue, 26 Jun 2018 15:14:58 +0000 (-0600)
Subject: block: Fix transfer when chunk sectors exceeds max
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=15bfd21fbc5d35834b9ea383dc458a1f0c9e3434;p=linux.git

block: Fix transfer when chunk sectors exceeds max

A device may have boundary restrictions where the number of sectors
between boundaries exceeds its max transfer size. In this case, we need
to cap the max size to the smaller of the two limits.

Reported-by: Jitendra Bhivare <jitendra.bhivare@broadcom.com>
Tested-by: Jitendra Bhivare <jitendra.bhivare@broadcom.com>
Cc: <stable@vger.kernel.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 9154570edf296..79226ca8f80f2 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1119,8 +1119,8 @@ static inline unsigned int blk_max_size_offset(struct request_queue *q,
 	if (!q->limits.chunk_sectors)
 		return q->limits.max_sectors;
 
-	return q->limits.chunk_sectors -
-			(offset & (q->limits.chunk_sectors - 1));
+	return min(q->limits.max_sectors, (unsigned int)(q->limits.chunk_sectors -
+			(offset & (q->limits.chunk_sectors - 1))));
 }
 
 static inline unsigned int blk_rq_get_max_sectors(struct request *rq,