net/virtio: fix link status always being up

The virtio port link status will always be UP, even the port is stopped:

    testpmd> port stop 0
    Stopping ports...
    Checking link statuses...
    Port 0 Link Up - speed 10000 Mbps - full-duplex
    Done

The link status is queried by link_update callback when LSC is disabled.
Which in turn queries the "status" field.  However, the "status" is
read-only. I couldn't think of some proper ways to change the status
without doing device reset.

Instead of doing (the heavy) reset at stop, this patch introduced a flag,
which is set to 1 and 0 on start and stop, respectively. When it's set to
0, the link status is set to DOWN unconditionally.

Fixes: a85786dc816f ("virtio: fix states handling during initialization")
Cc: stable@dpdk.org
Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>

diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
index f0a0219..e6c57b3 100644 (file)
--- a/drivers/net/virtio/virtio_ethdev.c
+++ b/drivers/net/virtio/virtio_ethdev.c
@@ -1776,6 +1776,7 @@ virtio_dev_start(struct rte_eth_dev *dev)
                txvq = dev->data->tx_queues[i];
                VIRTQUEUE_DUMP(txvq->vq);
        }
+       hw->started = 1;
 
        return 0;
 }
@@ -1831,6 +1832,7 @@ static void virtio_dev_free_mbufs(struct rte_eth_dev *dev)
 static void
 virtio_dev_stop(struct rte_eth_dev *dev)
 {
+       struct virtio_hw *hw = dev->data->dev_private;
        struct rte_eth_link link;
        struct rte_intr_conf *intr_conf = &dev->data->dev_conf.intr_conf;
 
@@ -1839,6 +1841,7 @@ virtio_dev_stop(struct rte_eth_dev *dev)
        if (intr_conf->lsc || intr_conf->rxq)
                rte_intr_disable(dev->intr_handle);
 
+       hw->started = 0;
        memset(&link, 0, sizeof(link));
        virtio_dev_atomic_write_link_status(dev, &link);
 }
@@ -1855,7 +1858,9 @@ virtio_dev_link_update(struct rte_eth_dev *dev, __rte_unused int wait_to_complet
        link.link_duplex = ETH_LINK_FULL_DUPLEX;
        link.link_speed  = SPEED_10G;
 
-       if (vtpci_with_feature(hw, VIRTIO_NET_F_STATUS)) {
+       if (hw->started == 0) {
+               link.link_status = ETH_LINK_DOWN;
+       } else if (vtpci_with_feature(hw, VIRTIO_NET_F_STATUS)) {
                PMD_INIT_LOG(DEBUG, "Get link status from hw");
                vtpci_read_dev_config(hw,
                                offsetof(struct virtio_net_config, status),

diff --git a/drivers/net/virtio/virtio_pci.h b/drivers/net/virtio/virtio_pci.h
index 0362acd..e7290d7 100644 (file)
--- a/drivers/net/virtio/virtio_pci.h
+++ b/drivers/net/virtio/virtio_pci.h
@@ -253,6 +253,7 @@ struct virtio_hw {
        uint64_t    req_guest_features;
        uint64_t    guest_features;
        uint32_t    max_queue_pairs;
+       uint16_t    started;
        uint16_t        max_mtu;
        uint16_t    vtnet_hdr_size;
        uint8_t     vlan_strip;