IB/core: refactor ib_create_qp

Split the XRC magic into a separate function, and return early on failure
to make the initialization code readable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/core/verbs.c

@@ -723,23 +723,11 @@ struct ib_qp *ib_open_qp(struct ib_xrcd *xrcd,
 }
 EXPORT_SYMBOL(ib_open_qp);
 
-struct ib_qp *ib_create_qp(struct ib_pd *pd,
+static struct ib_qp *ib_create_xrc_qp(struct ib_qp *qp,
 		struct ib_qp_init_attr *qp_init_attr)
 {
-	struct ib_qp *qp, *real_qp;
-	struct ib_device *device;
-
-	device = pd ? pd->device : qp_init_attr->xrcd->device;
-	qp = device->create_qp(pd, qp_init_attr, NULL);
-
-	if (!IS_ERR(qp)) {
-		qp->device     = device;
-		qp->real_qp    = qp;
-		qp->uobject    = NULL;
-		qp->qp_type    = qp_init_attr->qp_type;
+	struct ib_qp *real_qp = qp;
 
-		atomic_set(&qp->usecnt, 0);
-		if (qp_init_attr->qp_type == IB_QPT_XRC_TGT) {
 	qp->event_handler = __ib_shared_qp_event_handler;
 	qp->qp_context = qp;
 	qp->pd = NULL;
@@ -749,14 +737,34 @@ struct ib_qp *ib_create_qp(struct ib_pd *pd,
 	atomic_inc(&qp_init_attr->xrcd->usecnt);
 	INIT_LIST_HEAD(&qp->open_list);
 
-			real_qp = qp;
 	qp = __ib_open_qp(real_qp, qp_init_attr->event_handler,
 			  qp_init_attr->qp_context);
 	if (!IS_ERR(qp))
 		__ib_insert_xrcd_qp(qp_init_attr->xrcd, real_qp);
 	else
 		real_qp->device->destroy_qp(real_qp);
-		} else {
+	return qp;
+}
+
+struct ib_qp *ib_create_qp(struct ib_pd *pd,
+			   struct ib_qp_init_attr *qp_init_attr)
+{
+	struct ib_device *device = pd ? pd->device : qp_init_attr->xrcd->device;
+	struct ib_qp *qp;
+
+	qp = device->create_qp(pd, qp_init_attr, NULL);
+	if (IS_ERR(qp))
+		return qp;
+
+	qp->device     = device;
+	qp->real_qp    = qp;
+	qp->uobject    = NULL;
+	qp->qp_type    = qp_init_attr->qp_type;
+
+	atomic_set(&qp->usecnt, 0);
+	if (qp_init_attr->qp_type == IB_QPT_XRC_TGT)
+		return ib_create_xrc_qp(qp, qp_init_attr);
+
 	qp->event_handler = qp_init_attr->event_handler;
 	qp->qp_context = qp_init_attr->qp_context;
 	if (qp_init_attr->qp_type == IB_QPT_XRC_INI) {
@@ -776,9 +784,6 @@ struct ib_qp *ib_create_qp(struct ib_pd *pd,
 
 	atomic_inc(&pd->usecnt);
 	atomic_inc(&qp_init_attr->send_cq->usecnt);
-		}
-	}
-
 	return qp;
 }
 EXPORT_SYMBOL(ib_create_qp);