Re: [PATCH v5 1/2] net: dsa: Add protocol support for 802.1AD when adding or deleting vlan for dsa switch port

[Nikolay Aleksandrov <nikolay@cumulusnetworks.com>]

On 07/08/2020 14:13, hongbo.wang@nxp.com wrote:
> From: "hongbo.wang" <hongbo.wang@nxp.com>
> 
> the following command will be supported:
> 
> Set bridge's vlan protocol:
>     ip link set br0 type bridge vlan_protocol 802.1ad
> Add VLAN:
>     ip link add link swp1 name swp1.100 type vlan protocol 802.1ad id 100
> Delete VLAN:
>     ip link del link swp1 name swp1.100
> 
> Signed-off-by: hongbo.wang <hongbo.wang@nxp.com>
> ---
>  include/net/switchdev.h   |  1 +
>  net/bridge/br_switchdev.c | 22 ++++++++++++++++
>  net/dsa/dsa_priv.h        |  4 +--
>  net/dsa/port.c            |  6 +++--
>  net/dsa/slave.c           | 53 ++++++++++++++++++++++++++-------------
>  net/dsa/tag_8021q.c       |  4 +--
>  6 files changed, 66 insertions(+), 24 deletions(-)
> 

Hi,
Please put the bridge changes in a separate patch with proper description.
Reviewers would easily miss these bridge changes. Also I believe net-next
is currently closed and that's where these patches should be targeted (i.e.
have net-next after PATCH in the subject). Few more comments below.

Thanks,
 Nik

> diff --git a/include/net/switchdev.h b/include/net/switchdev.h
> index ff2246914301..7594ea82879f 100644
> --- a/include/net/switchdev.h
> +++ b/include/net/switchdev.h
> @@ -97,6 +97,7 @@ struct switchdev_obj_port_vlan {
>  	u16 flags;
>  	u16 vid_begin;
>  	u16 vid_end;
> +	u16 proto;
>  };
>  
>  #define SWITCHDEV_OBJ_PORT_VLAN(OBJ) \
> diff --git a/net/bridge/br_switchdev.c b/net/bridge/br_switchdev.c
> index 015209bf44aa..bcfa00d6d5eb 100644
> --- a/net/bridge/br_switchdev.c
> +++ b/net/bridge/br_switchdev.c
> @@ -146,6 +146,26 @@ br_switchdev_fdb_notify(const struct net_bridge_fdb_entry *fdb, int type)
>  	}
>  }
>  
> +static u16 br_switchdev_get_bridge_vlan_proto(struct net_device *dev)

const

> +{
> +	u16 vlan_proto = ETH_P_8021Q;
> +	struct net_device *br = NULL;
> +	struct net_bridge_port *p;
> +
> +	if (netif_is_bridge_master(dev)) {
> +		br = dev;
> +	} else if (netif_is_bridge_port(dev)) {

You can use br_port_get_rtnl_rcu() and just check if p is not NULL.
But in general these helpers are used only on bridge devices, I don't think you
can reach them with a device that's not either a bridge or a port. So you can just
check if it's a bridge master else it's a port.

> +		p = br_port_get_rcu(dev);
> +		if (p && p->br)

No need to check for p->br, it always exists.

> +			br = p->br->dev;
> +	}
> +
> +	if (br)
> +		br_vlan_get_proto(br, &vlan_proto);
> +
> +	return vlan_proto;
> +}
> +
>  int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid, u16 flags,
>  			       struct netlink_ext_ack *extack)
>  {
> @@ -157,6 +177,7 @@ int br_switchdev_port_vlan_add(struct net_device *dev, u16 vid, u16 flags,
>  		.vid_end = vid,
>  	};
>  
> +	v.proto = br_switchdev_get_bridge_vlan_proto(dev);
>  	return switchdev_port_obj_add(dev, &v.obj, extack);
>  }
>  
> @@ -169,5 +190,6 @@ int br_switchdev_port_vlan_del(struct net_device *dev, u16 vid)
>  		.vid_end = vid,
>  	};
>  
> +	v.proto = br_switchdev_get_bridge_vlan_proto(dev);
>  	return switchdev_port_obj_del(dev, &v.obj);
>  }