Re: [PATCH v2 net-next 05/15] net: dsa: sja1105: save/restore VLANs using a delta commit method

[Florian Fainelli]

On 5/11/2020 6:53 AM, Vladimir Oltean wrote:
> From: Vladimir Oltean <vladimir.oltean@xxxxxxx>
> 
> Managing the VLAN table that is present in hardware will become very
> difficult once we add a third operating state
> (best_effort_vlan_filtering). That is because correct cleanup (not too
> little, not too much) becomes virtually impossible, when VLANs can be
> added from the bridge layer, from dsa_8021q for basic tagging, for
> cross-chip bridging, as well as retagging rules for sub-VLANs and
> cross-chip sub-VLANs. So we need to rethink VLAN interaction with the
> switch in a more scalable way.
> 
> In preparation for that, use the priv->expect_dsa_8021q boolean to
> classify any VLAN request received through .port_vlan_add or
> .port_vlan_del towards either one of 2 internal lists: bridge VLANs and
> dsa_8021q VLANs.
> 
> Then, implement a central sja1105_build_vlan_table method that creates a
> VLAN configuration from scratch based on the 2 lists of VLANs kept by
> the driver, and based on the VLAN awareness state. Currently, if we are
> VLAN-unaware, install the dsa_8021q VLANs, otherwise the bridge VLANs.
> 
> Then, implement a delta commit procedure that identifies which VLANs
> from this new configuration are actually different from the config
> previously committed to hardware. We apply the delta through the dynamic
> configuration interface (we don't reset the switch). The result is that
> the hardware should see the exact sequence of operations as before this
> patch.
> 
> This also helps remove the "br" argument passed to
> dsa_8021q_crosschip_bridge_join, which it was only using to figure out
> whether it should commit the configuration back to us or not, based on
> the VLAN awareness state of the bridge. We can simplify that, by always
> allowing those VLANs inside of our dsa_8021q_vlans list, and committing
> those to hardware when necessary.
> 
> Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>

Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
-- 
Florian