From: Bart Van Assche <bart.vanassche@wdc.com>
Date: Mon, 25 Jun 2018 22:51:30 +0000 (-0700)
Subject: drbd: Fix drbd_request_prepare() discard handling
X-Git-Tag: v4.17.19~176
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7d208fd9097691b6617d4bb0c90cc712e560b761;p=thirdparty%2Fkernel%2Fstable.git

drbd: Fix drbd_request_prepare() discard handling

[ Upstream commit fad2d4ef636654e926d374ef038f4cd4286661f6 ]

Fix the test that verifies whether bio_op(bio) represents a discard
or write zeroes operation. Compile-tested only.

Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Fixes: 7435e9018f91 ("drbd: zero-out partial unaligned discards on local backend")
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/block/drbd/drbd_req.c b/drivers/block/drbd/drbd_req.c
index a500e738d9299..f0ccb0a2b3bff 100644
--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -1244,8 +1244,8 @@ drbd_request_prepare(struct drbd_device *device, struct bio *bio, unsigned long
 	_drbd_start_io_acct(device, req);
 
 	/* process discards always from our submitter thread */
-	if ((bio_op(bio) & REQ_OP_WRITE_ZEROES) ||
-	    (bio_op(bio) & REQ_OP_DISCARD))
+	if (bio_op(bio) == REQ_OP_WRITE_ZEROES ||
+	    bio_op(bio) == REQ_OP_DISCARD)
 		goto queue_for_submitter_thread;
 
 	if (rw == WRITE && req->private_bio && req->i.size