Re: [net-next-2.6 PATCH 1/2] Add ndo_set_vf_port_profile

[Scott Feldman <scofeldm@cisco.com>]

On 4/27/10 5:35 AM, "Arnd Bergmann" <arnd@arndb.de> wrote:

> On Tuesday 27 April 2010, Scott Feldman wrote:
>>> Yes, I believe that's there today:
>>> 
>>>     NLA_PUT_U32(skb, IFLA_NUM_VF, dev_num_vf(dev->dev.parent));
>>> 
>>> The number of VFs is returned in RTM_GETLINK.  But, it's only returned if:
>>> 
>>>     if (dev->netdev_ops->ndo_get_vf_config && dev->dev.parent)
>>> 
>>> For my proposal, I'll need to return IFLA_NUM_VF unconditionally so callers
>>> can get num VFs.
>> 
>> Hmmm...seems IFLA_NUM_VF assumes a PCI device supporting SR-IOV when it uses
>> dev_num_vf().  I think a better option would have been to query the device
>> for the number of VFs, without assuming SR-IOV or even PCI.
>> 
>> I see a ndo_get_num_vf() coming...
> 
> Shouldn't the number of registered port profiles be totally independent of
> the number of virtual functions?
> 
> Any of the VFs could multiplex multiple guests using macvlan, which means you
> need to register each guest separately, not each VF.
> 
> Anything that ties port profiles to VFs seems fundamentally flawed AFAICT,
> at least when we want to extend this to adapters that don't do it in firmware.

Ya, I tend I agree.  Let's just make port-profile a setting of any netdev,
an eth, macvtap, eth.x, bond, etc.  That's probably what I should have done
in the first place.  Something like:

       ip link set DEVICE [ { up | down } ]
                          [ arp { on | off } ]
                            <...clip...>
                          [ alias NAME ]
                          [ vf NUM [ mac LLADDR ]
                                   [ vlan VLANID [ qos VLAN-QOS ] ]
                                   [ rate TXRATE ] ]
                          [ port_profile [ PORT-PROFILE
                                   [ mac LLADDR ]
                                   [ host_uuid HOST_UUID ]
                                   [ client_uuid CLIENT_UUID ]
                                   [ client_name CLIENT_NAME ] ] ] ]
       ip link show [ DEVICE ]

I think I was trying to be too accommodating for models with VFs, but it
doesn't matter like you point out.

This way, I can get the RTM_GETLINK to return the port-profile in use.

New patches coming soon...

-scott