Re: [PATCH net-next v2 2/4] net: hsr: Add VLAN CTAG filter support

[Vadim Fedorenko <vadim.fedorenko@linux.dev>]

On 24/10/2024 11:30, MD Danish Anwar wrote:
> From: Murali Karicheri <m-karicheri2@ti.com>
> 
> This patch adds support for VLAN ctag based filtering at slave devices.
> The slave ethernet device may be capable of filtering ethernet packets
> based on VLAN ID. This requires that when the VLAN interface is created
> over an HSR/PRP interface, it passes the VID information to the
> associated slave ethernet devices so that it updates the hardware
> filters to filter ethernet frames based on VID. This patch adds the
> required functions to propagate the vid information to the slave
> devices.
> 
> Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
> Signed-off-by: MD Danish Anwar <danishanwar@ti.com>
> ---
>   net/hsr/hsr_device.c | 71 +++++++++++++++++++++++++++++++++++++++++++-
>   1 file changed, 70 insertions(+), 1 deletion(-)
> 
> diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
> index 0ca47ebb01d3..ff586bdc2bde 100644
> --- a/net/hsr/hsr_device.c
> +++ b/net/hsr/hsr_device.c
> @@ -515,6 +515,68 @@ static void hsr_change_rx_flags(struct net_device *dev, int change)
>   	}
>   }
>   
> +static int hsr_ndo_vlan_rx_add_vid(struct net_device *dev,
> +				   __be16 proto, u16 vid)
> +{
> +	struct hsr_port *port;
> +	struct hsr_priv *hsr;
> +	int ret = 0;
> +
> +	hsr = netdev_priv(dev);
> +
> +	hsr_for_each_port(hsr, port) {
> +		if (port->type == HSR_PT_MASTER)
> +			continue;
> +
> +		ret = vlan_vid_add(port->dev, proto, vid);
> +		switch (port->type) {
> +		case HSR_PT_SLAVE_A:
> +			if (ret) {
> +				netdev_err(dev, "add vid failed for Slave-A\n");
> +				return ret;
> +			}
> +			break;
> +
> +		case HSR_PT_SLAVE_B:
> +			if (ret) {
> +				/* clean up Slave-A */
> +				netdev_err(dev, "add vid failed for Slave-B\n");
> +				vlan_vid_del(port->dev, proto, vid);
> +				return ret;
> +			}
> +			break;
> +		default:
> +			break;
> +		}
> +	}
> +
> +	return 0;
> +}

This function doesn't match with hsr_ndo_vlan_rx_kill_vid().
vlan_vid_add() can potentially be executed for port->type
equals to HSR_PT_INTERLINK, but the result will be ignored. And
the vlan_vid_del() will never happen in this case. Is it desired
behavior? Maybe it's better to synchronize add/del code and refactor
error path to avoid coping the code?

> +
> +static int hsr_ndo_vlan_rx_kill_vid(struct net_device *dev,
> +				    __be16 proto, u16 vid)
> +{
> +	struct hsr_port *port;
> +	struct hsr_priv *hsr;
> +
> +	hsr = netdev_priv(dev);
> +
> +	hsr_for_each_port(hsr, port) {
> +		if (port->type == HSR_PT_MASTER)
> +			continue;
> +		switch (port->type) {
> +		case HSR_PT_SLAVE_A:
> +		case HSR_PT_SLAVE_B:
> +			vlan_vid_del(port->dev, proto, vid);
> +			break;
> +		default:
> +			break;
> +		}
> +	}
> +
> +	return 0;
> +}
> +
>   static const struct net_device_ops hsr_device_ops = {
>   	.ndo_change_mtu = hsr_dev_change_mtu,
>   	.ndo_open = hsr_dev_open,
> @@ -523,6 +585,8 @@ static const struct net_device_ops hsr_device_ops = {
>   	.ndo_change_rx_flags = hsr_change_rx_flags,
>   	.ndo_fix_features = hsr_fix_features,
>   	.ndo_set_rx_mode = hsr_set_rx_mode,
> +	.ndo_vlan_rx_add_vid = hsr_ndo_vlan_rx_add_vid,
> +	.ndo_vlan_rx_kill_vid = hsr_ndo_vlan_rx_kill_vid,
>   };
>   
>   static const struct device_type hsr_type = {
> @@ -569,7 +633,8 @@ void hsr_dev_setup(struct net_device *dev)
>   
>   	dev->hw_features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
>   			   NETIF_F_GSO_MASK | NETIF_F_HW_CSUM |
> -			   NETIF_F_HW_VLAN_CTAG_TX;
> +			   NETIF_F_HW_VLAN_CTAG_TX |
> +			   NETIF_F_HW_VLAN_CTAG_FILTER;
>   
>   	dev->features = dev->hw_features;
>   }
> @@ -647,6 +712,10 @@ int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
>   	    (slave[1]->features & NETIF_F_HW_HSR_FWD))
>   		hsr->fwd_offloaded = true;
>   
> +	if ((slave[0]->features & NETIF_F_HW_VLAN_CTAG_FILTER) &&
> +	    (slave[1]->features & NETIF_F_HW_VLAN_CTAG_FILTER))
> +		hsr_dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
> +
>   	res = register_netdevice(hsr_dev);
>   	if (res)
>   		goto err_unregister;