On 16-11-21 03:23 PM, Michael S. Tsirkin wrote:
> On Sat, Nov 19, 2016 at 06:49:34PM -0800, John Fastabend wrote:
>> 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;
>> + }
>
> I don't get this last warning. VIRTIO_NET_F_CTRL_GUEST_OFFLOADS
> was exposes by legacy devices, I don't think it's related to
> VIRTIO_F_VERSION_1.
>
OK looks like I can just drop the else if branch here.
Thanks,
John
