From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andy Gospodarek <gospo@cumulusnetworks.com>
Subject: Re: [patch net-next 0/9] Introduce devlink interface and first
 drivers to use it
Date: Tue, 23 Feb 2016 10:55:28 -0500
Message-ID: <20160223155527.GS33942@gospo.home.greyhouse.net>
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To: Jiri Pirko <jiri@resnulli.us>
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On Tue, Feb 23, 2016 at 03:45:51PM +0100, Jiri Pirko wrote:
> Tue, Feb 23, 2016 at 03:34:19PM CET, gospo@cumulusnetworks.com wrote:
> 
> <snip>
> >> 
> >> >> 	myhost:~$ dl port show
> >> >> 	devlink0/1: type eth netdev ens4
> >> >                             ^^^^^^^^^^^
> >> >> 	devlink0/2: type ib ibdev mlx4_0
> >> >                            ^^^^^^^^^^^^
> >> >I think my only other question about this implementation is whether or
> >> >not one would really want to have the true netdev/ibdev names mapped
> >> >here.
> >> >
> >> >Would be as reasonable to simply specify the type (and there may be more
> >> >types within ethernet that could be useful in multi-chip configurations)
> >> >and then let normal infrastructure that exists today figure out how to
> >> >map the names for the netdevs to the devices?
> >> 
> >> What normal infrastructure you have in mind? There is no info about
> >> devlink port mapping to netdev/ibdev anywhere. Only here. I might be
> >> missing something but I fail to see what's wrong with it.
> >
> >I was simply wondering out loud if we _really_ wanted to name netdevs
> >this way.  I was suggesting that output could be like this:
> >
> >myhost:~$ dl port show
> >devlink0/1: type eth
> >devlink0/2: type ib 
> >
> >mnd that udev/systemd/biosdevname/etc would take care of naming the
> >device whataever it wanted.  This appears to be essentially the same
> >concern Hannes has.
> 
> Wait. The only thing which will be renamed by udev is "devlink0". The
> suffixes "/1" and "/2" are direct indexes as used inside the driver.
> 
> And you need some link to netdev in case netdev exists - therefore
> "netdev ens4" attribute is there. There's no other way to get the
> mapping of "devlink0/1" to "ens4" anywhere else.

So I think I had invisioned a slightly different workflow than what you
just described.

- Load PCI driver
- Setup devlink attributes for your hardware
- Create netdevs in network driver based on those attributes

You don't need a netdev to reference any of the devlink specific
parameters do you?