+int
+virtio_dev_pause(struct rte_eth_dev *dev)
+{
+ struct virtio_hw *hw = dev->data->dev_private;
+
+ rte_spinlock_lock(&hw->state_lock);
+
+ if (hw->started == 0) {
+ /* Device is just stopped. */
+ rte_spinlock_unlock(&hw->state_lock);
+ return -1;
+ }
+ hw->started = 0;
+ /*
+ * Prevent the worker threads from touching queues to avoid contention,
+ * 1 ms should be enough for the ongoing Tx function to finish.
+ */
+ rte_delay_ms(1);
+ return 0;
+}
+
+/*
+ * Recover hw state to let the worker threads continue.
+ */
+void
+virtio_dev_resume(struct rte_eth_dev *dev)
+{
+ struct virtio_hw *hw = dev->data->dev_private;
+
+ hw->started = 1;
+ rte_spinlock_unlock(&hw->state_lock);
+}
+
+/*
+ * Should be called only after device is paused.
+ */
+int
+virtio_inject_pkts(struct rte_eth_dev *dev, struct rte_mbuf **tx_pkts,
+ int nb_pkts)
+{
+ struct virtio_hw *hw = dev->data->dev_private;
+ struct virtnet_tx *txvq = dev->data->tx_queues[0];
+ int ret;
+
+ hw->inject_pkts = tx_pkts;
+ ret = dev->tx_pkt_burst(txvq, tx_pkts, nb_pkts);
+ hw->inject_pkts = NULL;
+
+ return ret;
+}
+
+static void
+virtio_notify_peers(struct rte_eth_dev *dev)
+{
+ struct virtio_hw *hw = dev->data->dev_private;
+ struct virtnet_rx *rxvq;
+ struct rte_mbuf *rarp_mbuf;
+
+ if (!dev->data->rx_queues)
+ return;
+
+ rxvq = dev->data->rx_queues[0];
+ if (!rxvq)
+ return;
+
+ rarp_mbuf = rte_net_make_rarp_packet(rxvq->mpool,
+ (struct rte_ether_addr *)hw->mac_addr);
+ if (rarp_mbuf == NULL) {
+ PMD_DRV_LOG(ERR, "failed to make RARP packet.");
+ return;
+ }
+
+ /* If virtio port just stopped, no need to send RARP */
+ if (virtio_dev_pause(dev) < 0) {
+ rte_pktmbuf_free(rarp_mbuf);
+ return;
+ }
+
+ virtio_inject_pkts(dev, &rarp_mbuf, 1);
+ virtio_dev_resume(dev);
+}
+
+static void
+virtio_ack_link_announce(struct rte_eth_dev *dev)
+{
+ struct virtio_hw *hw = dev->data->dev_private;
+ struct virtio_pmd_ctrl ctrl;
+
+ ctrl.hdr.class = VIRTIO_NET_CTRL_ANNOUNCE;
+ ctrl.hdr.cmd = VIRTIO_NET_CTRL_ANNOUNCE_ACK;
+
+ virtio_send_command(hw->cvq, &ctrl, NULL, 0);
+}
+
+/*
+ * Process virtio config changed interrupt. Call the callback
+ * if link state changed, generate gratuitous RARP packet if
+ * the status indicates an ANNOUNCE.
+ */
+void
+virtio_interrupt_handler(void *param)