virtio_net: separate virtnet_rx_resize()

This patch separates two sub-functions from virtnet_rx_resize():

* virtnet_rx_pause
* virtnet_rx_resume

Then the subsequent reset rx for xsk can share these two functions.
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://patch.msgid.link/20240708112537.96291-3-xuanzhuo@linux.alibaba.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/virtio_net.c

@@ -2665,28 +2665,41 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
 	return NETDEV_TX_OK;
 }
 
-static int virtnet_rx_resize(struct virtnet_info *vi,
-			     struct receive_queue *rq, u32 ring_num)
+static void virtnet_rx_pause(struct virtnet_info *vi, struct receive_queue *rq)
 {
 	bool running = netif_running(vi->dev);
-	int err, qindex;
-
-	qindex = rq - vi->rq;
 
 	if (running) {
 		napi_disable(&rq->napi);
 		virtnet_cancel_dim(vi, &rq->dim);
 	}
+}
 
-	err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_unmap_free_buf);
-	if (err)
-		netdev_err(vi->dev, "resize rx fail: rx queue index: %d err: %d\n", qindex, err);
+static void virtnet_rx_resume(struct virtnet_info *vi, struct receive_queue *rq)
+{
+	bool running = netif_running(vi->dev);
 
 	if (!try_fill_recv(vi, rq, GFP_KERNEL))
 		schedule_delayed_work(&vi->refill, 0);
 
 	if (running)
 		virtnet_napi_enable(rq->vq, &rq->napi);
+}
+
+static int virtnet_rx_resize(struct virtnet_info *vi,
+			     struct receive_queue *rq, u32 ring_num)
+{
+	int err, qindex;
+
+	qindex = rq - vi->rq;
+
+	virtnet_rx_pause(vi, rq);
+
+	err = virtqueue_resize(rq->vq, ring_num, virtnet_rq_unmap_free_buf);
+	if (err)
+		netdev_err(vi->dev, "resize rx fail: rx queue index: %d err: %d\n", qindex, err);
+
+	virtnet_rx_resume(vi, rq);
 	return err;
 }