Re: [PATCH iwl-next v4 06/13] ice: Implement basic eswitch bridge setup

[Simon Horman <simon.horman@corigine.com>]

On Mon, Jun 05, 2023 at 10:47:09AM +0000, Drewek, Wojciech wrote:
> 
> 
> > -----Original Message-----
> > From: Simon Horman <simon.horman@corigine.com>
> > Sent: niedziela, 4 czerwca 2023 15:59
> > To: Drewek, Wojciech <wojciech.drewek@intel.com>
> > Cc: intel-wired-lan@lists.osuosl.org; netdev@vger.kernel.org; Lobakin, Aleksander <aleksander.lobakin@intel.com>; Ertman, David M
> > <david.m.ertman@intel.com>; michal.swiatkowski@linux.intel.com; marcin.szycik@linux.intel.com; Chmielewski, Pawel
> > <pawel.chmielewski@intel.com>; Samudrala, Sridhar <sridhar.samudrala@intel.com>; pmenzel@molgen.mpg.de;
> > dan.carpenter@linaro.org
> > Subject: Re: [PATCH iwl-next v4 06/13] ice: Implement basic eswitch bridge setup
> > 
> > On Wed, May 24, 2023 at 02:21:14PM +0200, Wojciech Drewek wrote:
> > > With this patch, ice driver is able to track if the port
> > > representors or uplink port were added to the linux bridge in
> > > switchdev mode. Listen for NETDEV_CHANGEUPPER events in order to
> > > detect this. ice_esw_br data structure reflects the linux bridge
> > > and stores all the ports of the bridge (ice_esw_br_port) in
> > > xarray, it's created when the first port is added to the bridge and
> > > freed once the last port is removed. Note that only one bridge is
> > > supported per eswitch.
> > >
> > > Bridge port (ice_esw_br_port) can be either a VF port representor
> > > port or uplink port (ice_esw_br_port_type). In both cases bridge port
> > > holds a reference to the VSI, VF's VSI in case of the PR and uplink
> > > VSI in case of the uplink. VSI's index is used as an index to the
> > > xarray in which ports are stored.
> > >
> > > Add a check which prevents configuring switchdev mode if uplink is
> > > already added to any bridge. This is needed because we need to listen
> > > for NETDEV_CHANGEUPPER events to record if the uplink was added to
> > > the bridge. Netdevice notifier is registered after eswitch mode
> > > is changed top switchdev.
> > 
> > Hi Wojciech,
> > 
> > Does the uplink here model both a physical port and the PF link between the
> > host and the NIC?  If so, then I think this is ok.
> > 
> > I mention this because I am more familiar with a model where these are
> > separated, in which case I think it would probably be an uplink representor
> > that is added to the bridge. And I want to make sure make sure that I
> > understand the model used here correctly.
> 
> In our design we don't have separate uplink rpresentor. PF netdev serves as uplink
> repr once the eswitch mode is changed to switchdev.

Understood. In that case I think this patch looks good.

Reviewed-by: Simon Horman <simon.horman@corigine.com>