This adds support for dynamically setting the LRO feature flag. The message to control guest features in the backend uses the CTRL_GUEST_OFFLOADS msg type.
Signed-off-by: John Fastabend <john.r.fastab...@intel.com> --- drivers/net/virtio_net.c | 45 ++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 44 insertions(+), 1 deletion(-) diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c index ca5239a..8189e5b 100644 --- a/drivers/net/virtio_net.c +++ b/drivers/net/virtio_net.c @@ -1419,6 +1419,41 @@ static void virtnet_init_settings(struct net_device *dev) .set_settings = virtnet_set_settings, }; +static int virtnet_set_features(struct net_device *netdev, + netdev_features_t features) +{ + struct virtnet_info *vi = netdev_priv(netdev); + struct virtio_device *vdev = vi->vdev; + struct scatterlist sg; + u64 offloads = 0; + + if (features & NETIF_F_LRO) + offloads |= (1 << VIRTIO_NET_F_GUEST_TSO4) | + (1 << VIRTIO_NET_F_GUEST_TSO6); + + if (features & NETIF_F_RXCSUM) + offloads |= (1 << VIRTIO_NET_F_GUEST_CSUM); + + if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) { + sg_init_one(&sg, &offloads, sizeof(uint64_t)); + if (!virtnet_send_command(vi, + VIRTIO_NET_CTRL_GUEST_OFFLOADS, + VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, + &sg)) { + dev_warn(&netdev->dev, + "Failed to set guest offloads by virtnet command.\n"); + return -EINVAL; + } + } else if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) && + !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) { + dev_warn(&netdev->dev, + "No support for setting offloads pre version_1.\n"); + return -EINVAL; + } + + return 0; +} + static const struct net_device_ops virtnet_netdev = { .ndo_open = virtnet_open, .ndo_stop = virtnet_close, @@ -1435,6 +1470,7 @@ static void virtnet_init_settings(struct net_device *dev) #ifdef CONFIG_NET_RX_BUSY_POLL .ndo_busy_poll = virtnet_busy_poll, #endif + .ndo_set_features = virtnet_set_features, }; static void virtnet_config_changed_work(struct work_struct *work) @@ -1810,6 +1846,12 @@ static int virtnet_probe(struct virtio_device *vdev) if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_CSUM)) dev->features |= NETIF_F_RXCSUM; + if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) && + virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6)) { + dev->features |= NETIF_F_LRO; + dev->hw_features |= NETIF_F_LRO; + } + dev->vlan_features = dev->features; /* MTU range: 68 - 65535 */ @@ -2047,7 +2089,8 @@ static int virtnet_restore(struct virtio_device *vdev) VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \ VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \ VIRTIO_NET_F_CTRL_MAC_ADDR, \ - VIRTIO_NET_F_MTU + VIRTIO_NET_F_MTU, \ + VIRTIO_NET_F_CTRL_GUEST_OFFLOADS static unsigned int features[] = { VIRTNET_FEATURES,