drbd: move put_ldev from __req_mod() to the endio callback

One invocation in the endio handler is good enough,
we don't need mention it for each of the different ways
it calls __req_mod().

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

drivers/block/drbd/drbd_req.c

@@ -441,7 +441,6 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		req->rq_state &= ~RQ_LOCAL_PENDING;
 
 		_req_may_be_done_not_susp(req, m);
-		put_ldev(mdev);
 		break;
 
 	case abort_disk_io:
@@ -458,15 +457,13 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what,
 
 		__drbd_chk_io_error(mdev, false);
 		_req_may_be_done_not_susp(req, m);
-		put_ldev(mdev);
 		break;
 
 	case read_ahead_completed_with_error:
 		/* it is legal to fail READA */
 		req->rq_state |= RQ_LOCAL_COMPLETED;
 		req->rq_state &= ~RQ_LOCAL_PENDING;
 		_req_may_be_done_not_susp(req, m);
-		put_ldev(mdev);
 		break;
 
 	case read_completed_with_error:
@@ -478,7 +475,6 @@ int __req_mod(struct drbd_request *req, enum drbd_req_event what,
 		D_ASSERT(!(req->rq_state & RQ_NET_MASK));
 
 		__drbd_chk_io_error(mdev, false);
-		put_ldev(mdev);
 
 	goto_queue_for_net_read:
 

drivers/block/drbd/drbd_worker.c

@@ -244,6 +244,7 @@ void drbd_endio_pri(struct bio *bio, int error)
 	spin_lock_irqsave(&mdev->req_lock, flags);
 	__req_mod(req, what, &m);
 	spin_unlock_irqrestore(&mdev->req_lock, flags);
+	put_ldev(mdev);
 
 	if (m.bio)
 		complete_master_bio(mdev, &m);