nvme: rdma: split controller bringup handling

Drivers must call nvme_uninit_ctrl after a successful nvme_init_ctrl.
Split the allocation side out to make the error handling boundary easier
to navigate. The nvme rdma driver's error handling had different returns
in the error goto label's, which harm readability.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

drivers/nvme/host/rdma.c

@@ -2237,12 +2237,11 @@ nvme_rdma_existing_controller(struct nvmf_ctrl_options *opts)
 	return found;
 }
 
-static struct nvme_ctrl *nvme_rdma_create_ctrl(struct device *dev,
+static struct nvme_rdma_ctrl *nvme_rdma_alloc_ctrl(struct device *dev,
 		struct nvmf_ctrl_options *opts)
 {
 	struct nvme_rdma_ctrl *ctrl;
 	int ret;
-	bool changed;
 
 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
 	if (!ctrl)
@@ -2304,6 +2303,26 @@ static struct nvme_ctrl *nvme_rdma_create_ctrl(struct device *dev,
 	if (ret)
 		goto out_kfree_queues;
 
+	return ctrl;
+
+out_kfree_queues:
+	kfree(ctrl->queues);
+out_free_ctrl:
+	kfree(ctrl);
+	return ERR_PTR(ret);
+}
+
+static struct nvme_ctrl *nvme_rdma_create_ctrl(struct device *dev,
+		struct nvmf_ctrl_options *opts)
+{
+	struct nvme_rdma_ctrl *ctrl;
+	bool changed;
+	int ret;
+
+	ctrl = nvme_rdma_alloc_ctrl(dev, opts);
+	if (IS_ERR(ctrl))
+		return ERR_CAST(ctrl);
+
 	changed = nvme_change_ctrl_state(&ctrl->ctrl, NVME_CTRL_CONNECTING);
 	WARN_ON_ONCE(!changed);
 
@@ -2326,11 +2345,6 @@ static struct nvme_ctrl *nvme_rdma_create_ctrl(struct device *dev,
 	if (ret > 0)
 		ret = -EIO;
 	return ERR_PTR(ret);
-out_kfree_queues:
-	kfree(ctrl->queues);
-out_free_ctrl:
-	kfree(ctrl);
-	return ERR_PTR(ret);
 }
 
 static struct nvmf_transport_ops nvme_rdma_transport = {