>-----Original Message----- >From: netdev-ow...@vger.kernel.org [mailto:netdev-ow...@vger.kernel.org] On >Behalf Of John Fastabend >Sent: Thursday, December 18, 2014 9:21 PM >To: Roopa Prabhu; Varlese, Marco >Cc: net...@vger.kernel.org; Thomas Graf; Jiri Pirko; sfel...@gmail.com; linux- >ker...@vger.kernel.org >Subject: Re: [RFC PATCH net-next v2 1/1] net: Support for switch port >configuration > >On 12/18/2014 10:14 AM, Roopa Prabhu wrote: >> On 12/18/14, 10:02 AM, Varlese, Marco wrote: >>> Removed unnecessary content for ease of reading... >>> >>>>>>>>> +/* Switch Port Attributes section */ >>>>>>>>> + >>>>>>>>> +enum { >>>>>>>>> + IFLA_ATTR_UNSPEC, >>>>>>>>> + IFLA_ATTR_LEARNING, >>>>>>>> Any reason you want learning here ?. This is covered as part of >>>>>>>> the bridge setlink attributes. >>>>>>>> >>>>>>> Yes, because the user may _not_ want to go through a bridge >>>>>>> interface >>>>>> necessarily. >>>>>> But, the bridge setlink/getlink interface was changed to accommodate >>>> 'self' >>>>>> for exactly such cases. >>>>>> I kind of understand your case for the other attributes (these are >>>>>> per port settings that switch asics provide). >>>>>> >>>>>> However, i don't understand the reason to pull in bridge attributes >here. >>>>>> >>>>> Maybe, I am missing something so you might help. The learning attribute - >>>> in my case - it is like all other attributes: a port attribute (as you >said, port >>>> settings that the switch provides per port). >>>>> So, what I was saying is "why the user shall go through a bridge to >configure >>>> the learning attribute"? From my perspective, it is as any other attribute >and >>>> as such configurable on the port. >>>> >>>> Thinking about this some more, i don't see why any of these attributes >>>> (except loopback. I dont understand the loopback attribute) cant be part >of >>>> the birdge port attributes. >>>> >>>> With this we will end up adding l2 attributes in two places: the general >link >>>> attributes and bridge attributes. >>>> >>>> And since we have gone down the path of using ndo_bridge_setlink/getlink >>>> with 'self'....we should stick to that for all l2 attributes. >>>> >>>> The idea of overloading ndo_bridge_set/getlink, was to have the same set >of >>>> attributes but support both cases where the user wants to go through the >>>> bridge driver or directly to the switch port driver. So, you are not >really going >>>> through the bridge driver if you use 'self' and >ndo_bridge_setlink/getlink. >>>> > >>> Roopa, one of the comments I got from Thomas Graf on my v1 patch >>> was that your patch and mine were supplementary ("I think Roopa's >>> patches are supplementary. Not all switchdev users will be backed >>> with a Linux Bridge. I therefore welcome your patches very >>> much")... I also understood by others that the patch made sense for >>> the same reason. I simply do not understand why these attributes >>> (and maybe others in the future) could not be configured directly >>> on a standard port but have to go through a bridge. >>> >> ok, i am very confused in that case. The whole moving of bridge >> attributes from the bridge driver to rtnetlink.c was to make the >> bridge attributes accessible to any driver who wants to set l2/bridge >> attributes on their switch ports. So, its unclear to me why we are >> doing this parallel thing again. This move to rtnetlink.c was done >> during the recent rocker support. so, maybe scott/jiri can elaborate >> more. > > >Not sure if this will add to the confusion or help. But you do not >need to have the bridge.ko loaded or netdev's attached to a bridge >to use the setlink/getlink ndo ops and netlink messages.
No you don't need bridge.ko to implement ndo_bridge_setlink/getlink. Rtnetlink invokes those ndos from code which does not depend on CONFIG_BRIDGE or the presence of bridge.ko. Calling some bridge exported functions such as br_fdb_external_learn_add/del requires the presence of bridge.ko and it only makes sense when the switch port device is enslaved to a bridge. > >This was intentionally done. Its already used with NIC devices to >configure embedded bridge settings such as VEB/VEPA. > >I think I'm just repeating Roopa though. > >-- >To unsubscribe from this list: send the line "unsubscribe netdev" in >the body of a message to majord...@vger.kernel.org >More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
