Re: [PATCH net-next v3 3/3] virtio-net: synchronize operstate with admin state on up/down

[Xuan Zhuo]

On Tue,  9 Jul 2024 16:02:14 +0800, Jason Wang <jasowang@xxxxxxxxxx> wrote:
> This patch synchronize operstate with admin state per RFC2863.
>
> This is done by trying to toggle the carrier upon open/close and
> synchronize with the config change work. This allows propagate status
> correctly to stacked devices like:
>
> ip link add link enp0s3 macvlan0 type macvlan
> ip link set link enp0s3 down
> ip link show
>
> Before this patch:
>
> 3: enp0s3: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 1000
>     link/ether 00:00:05:00:00:09 brd ff:ff:ff:ff:ff:ff
> ......
> 5: macvlan0@enp0s3: <BROADCAST,MULTICAST,UP,LOWER_UP,M-DOWN> mtu 1500 qdisc noqueue state UP mode DEFAULT group default qlen 1000
>     link/ether b2:a9:c5:04:da:53 brd ff:ff:ff:ff:ff:ff
>
> After this patch:
>
> 3: enp0s3: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state DOWN mode DEFAULT group default qlen 1000
>     link/ether 00:00:05:00:00:09 brd ff:ff:ff:ff:ff:ff
> ...
> 5: macvlan0@enp0s3: <NO-CARRIER,BROADCAST,MULTICAST,UP,M-DOWN> mtu 1500 qdisc noqueue state LOWERLAYERDOWN mode DEFAULT group default qlen 1000
>     link/ether b2:a9:c5:04:da:53 brd ff:ff:ff:ff:ff:ff
>
> Cc: Venkat Venkatsubra <venkat.x.venkatsubra@xxxxxxxxxx>
> Cc: Gia-Khanh Nguyen <gia-khanh.nguyen@xxxxxxxxxx>
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>

Reviewed-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>

> ---
>  drivers/net/virtio_net.c | 64 ++++++++++++++++++++++++----------------
>  1 file changed, 38 insertions(+), 26 deletions(-)
>
> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
> index 0b4747e81464..e6626ba25b29 100644
> --- a/drivers/net/virtio_net.c
> +++ b/drivers/net/virtio_net.c
> @@ -2476,6 +2476,25 @@ static void virtnet_cancel_dim(struct virtnet_info *vi, struct dim *dim)
>  	net_dim_work_cancel(dim);
>  }
>
> +static void virtnet_update_settings(struct virtnet_info *vi)
> +{
> +	u32 speed;
> +	u8 duplex;
> +
> +	if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_SPEED_DUPLEX))
> +		return;
> +
> +	virtio_cread_le(vi->vdev, struct virtio_net_config, speed, &speed);
> +
> +	if (ethtool_validate_speed(speed))
> +		vi->speed = speed;
> +
> +	virtio_cread_le(vi->vdev, struct virtio_net_config, duplex, &duplex);
> +
> +	if (ethtool_validate_duplex(duplex))
> +		vi->duplex = duplex;
> +}
> +
>  static int virtnet_open(struct net_device *dev)
>  {
>  	struct virtnet_info *vi = netdev_priv(dev);
> @@ -2494,6 +2513,18 @@ static int virtnet_open(struct net_device *dev)
>  			goto err_enable_qp;
>  	}
>
> +	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
> +		virtio_config_driver_enable(vi->vdev);
> +		/* Do not schedule the config change work as the
> +		 * config change notification might have been disabled
> +		 * by the virtio core. */
> +		virtio_config_changed(vi->vdev);
> +	} else {
> +		vi->status = VIRTIO_NET_S_LINK_UP;
> +		virtnet_update_settings(vi);
> +		netif_carrier_on(dev);
> +	}
> +
>  	return 0;
>
>  err_enable_qp:
> @@ -2936,12 +2967,19 @@ static int virtnet_close(struct net_device *dev)
>  	disable_delayed_refill(vi);
>  	/* Make sure refill_work doesn't re-enable napi! */
>  	cancel_delayed_work_sync(&vi->refill);
> +	/* Make sure config notification doesn't schedule config work */
> +	virtio_config_driver_disable(vi->vdev);
> +	/* Make sure status updating is cancelled */
> +	cancel_work_sync(&vi->config_work);
>
>  	for (i = 0; i < vi->max_queue_pairs; i++) {
>  		virtnet_disable_queue_pair(vi, i);
>  		virtnet_cancel_dim(vi, &vi->rq[i].dim);
>  	}
>
> +	vi->status &= ~VIRTIO_NET_S_LINK_UP;
> +	netif_carrier_off(dev);
> +
>  	return 0;
>  }
>
> @@ -4640,25 +4678,6 @@ static void virtnet_init_settings(struct net_device *dev)
>  	vi->duplex = DUPLEX_UNKNOWN;
>  }
>
> -static void virtnet_update_settings(struct virtnet_info *vi)
> -{
> -	u32 speed;
> -	u8 duplex;
> -
> -	if (!virtio_has_feature(vi->vdev, VIRTIO_NET_F_SPEED_DUPLEX))
> -		return;
> -
> -	virtio_cread_le(vi->vdev, struct virtio_net_config, speed, &speed);
> -
> -	if (ethtool_validate_speed(speed))
> -		vi->speed = speed;
> -
> -	virtio_cread_le(vi->vdev, struct virtio_net_config, duplex, &duplex);
> -
> -	if (ethtool_validate_duplex(duplex))
> -		vi->duplex = duplex;
> -}
> -
>  static u32 virtnet_get_rxfh_key_size(struct net_device *dev)
>  {
>  	return ((struct virtnet_info *)netdev_priv(dev))->rss_key_size;
> @@ -6000,13 +6019,6 @@ static int virtnet_probe(struct virtio_device *vdev)
>  	/* Assume link up if device can't report link status,
>  	   otherwise get link status from config. */
>  	netif_carrier_off(dev);
> -	if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_STATUS)) {
> -		schedule_work(&vi->config_work);
> -	} else {
> -		vi->status = VIRTIO_NET_S_LINK_UP;
> -		virtnet_update_settings(vi);
> -		netif_carrier_on(dev);
> -	}
>
>  	for (i = 0; i < ARRAY_SIZE(guest_offloads); i++)
>  		if (virtio_has_feature(vi->vdev, guest_offloads[i]))
> --
> 2.31.1
>