[PATCH 4.17 149/324] drbd: Fix drbd_request_prepare() discard handling

Greg Kroah-Hartman
2018-08-23T08:51:28Z

From: Bart Van Assche <bart.vanassche@wdc.com>

[ 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>
---
drivers/block/drbd/drbd_req.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/block/drbd/drbd_req.c
+++ b/drivers/block/drbd/drbd_req.c
@@ -1244,8 +1244,8 @@ drbd_request_prepare(struct drbd_device
_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