On Wed, Sep 30, 2020 at 10:03:00AM +0800, xiangxia.m....@gmail.com wrote:
> From: Tonghao Zhang <xiangxia.m....@gmail.com>
>
> Allow user configuring RXCSUM separately with ethtool -K,
> reusing the existing virtnet_set_guest_offloads helper
> that configures RXCSUM for XDP. This is conditional on
> VIRTIO_NET_F_CTRL_GUEST_OFFLOADS.
>
> If Rx checksum is disabled, LRO should also be disabled.
>
> Cc: Michael S. Tsirkin <m...@redhat.com>
> Cc: Jason Wang <jasow...@redhat.com>
> Signed-off-by: Tonghao Zhang <xiangxia.m....@gmail.com>
Acked-by: Michael S. Tsirkin <m...@redhat.com>
> ---
> v2:
> * LRO depends the rx csum
> * remove the unnecessary check
> ---
> drivers/net/virtio_net.c | 49 ++++++++++++++++++++++++++++++----------
> 1 file changed, 37 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 21b71148c532..5407a0106771 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -68,6 +68,8 @@ static const unsigned long guest_offloads[] = {
> (1ULL << VIRTIO_NET_F_GUEST_ECN) | \
> (1ULL << VIRTIO_NET_F_GUEST_UFO))
>
> +#define GUEST_OFFLOAD_CSUM_MASK (1ULL << VIRTIO_NET_F_GUEST_CSUM)
> +
> struct virtnet_stat_desc {
> char desc[ETH_GSTRING_LEN];
> size_t offset;
> @@ -2522,29 +2524,49 @@ static int virtnet_get_phys_port_name(struct
> net_device *dev, char *buf,
> return 0;
> }
>
> +static netdev_features_t virtnet_fix_features(struct net_device *netdev,
> + netdev_features_t features)
> +{
> + /* If Rx checksum is disabled, LRO should also be disabled.
> + * That is life. :)
> + */
> + if (!(features & NETIF_F_RXCSUM))
> + features &= ~NETIF_F_LRO;
> +
> + return features;
> +}
> +
> static int virtnet_set_features(struct net_device *dev,
> netdev_features_t features)
> {
> struct virtnet_info *vi = netdev_priv(dev);
> - u64 offloads;
> + u64 offloads = vi->guest_offloads &
> + vi->guest_offloads_capable;
> int err;
>
> - if ((dev->features ^ features) & NETIF_F_LRO) {
> - if (vi->xdp_queue_pairs)
> - return -EBUSY;
> + /* Don't allow configuration while XDP is active. */
> + if (vi->xdp_queue_pairs)
> + return -EBUSY;
>
> + if ((dev->features ^ features) & NETIF_F_LRO) {
> if (features & NETIF_F_LRO)
> - offloads = vi->guest_offloads_capable;
> + offloads |= GUEST_OFFLOAD_LRO_MASK;
> else
> - offloads = vi->guest_offloads_capable &
> - ~GUEST_OFFLOAD_LRO_MASK;
> + offloads &= ~GUEST_OFFLOAD_LRO_MASK;
> + }
>
> - err = virtnet_set_guest_offloads(vi, offloads);
> - if (err)
> - return err;
> - vi->guest_offloads = offloads;
> + if ((dev->features ^ features) & NETIF_F_RXCSUM) {
> + if (features & NETIF_F_RXCSUM)
> + offloads |= GUEST_OFFLOAD_CSUM_MASK;
> + else
> + offloads &= ~GUEST_OFFLOAD_CSUM_MASK;
> }
>
> + err = virtnet_set_guest_offloads(vi, offloads);
> + if (err)
> + return err;
> +
> + vi->guest_offloads = offloads;
> return 0;
> }
>
> @@ -2563,6 +2585,7 @@ static const struct net_device_ops virtnet_netdev = {
> .ndo_features_check = passthru_features_check,
> .ndo_get_phys_port_name = virtnet_get_phys_port_name,
> .ndo_set_features = virtnet_set_features,
> + .ndo_fix_features = virtnet_fix_features,
> };
>
> static void virtnet_config_changed_work(struct work_struct *work)
> @@ -3013,8 +3036,10 @@ static int virtnet_probe(struct virtio_device *vdev)
> if (virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO4) ||
> virtio_has_feature(vdev, VIRTIO_NET_F_GUEST_TSO6))
> dev->features |= NETIF_F_LRO;
> - if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS))
> + if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) {
> + dev->hw_features |= NETIF_F_RXCSUM;
> dev->hw_features |= NETIF_F_LRO;
> + }
>
> dev->vlan_features = dev->features;
>
> --
> 2.23.0
