Re: [PATCH v2] kni: use kni_ethtool_ops only with unknown drivers

[Stephen Hemminger <stephen@networkplumber.org>]

On Sat, 1 Dec 2018 14:12:54 +0300
Igor Ryzhov <iryzhov@nfware.com> wrote:

> Hi Stephen,
> 
> I also do not see the point of the current implementation of ethtool
> support.
> That's why I sent this patch – it enables ethtool_ops for all devices,
> independent of the underlying driver.
> Right now only .get_link is supported, but I am thinking about
> implementation of a larger set of functions, using req/resp queue, like
> netdev_ops functions are working.
> 
> Regarding the KNI itself, we use it as Linux mirror of physical port for:
> 1. Port configuration from Linux – such functions as set_mac, change_mtu,
> etc. And ethtool_ops will be used the same way.
> 2. Passing control-plane packets to Linux.
> 
> Can virtio user be used the same way, as a mirror of physical port?
> 
> Best regards,
> Igor

In Linux if device does not supply get_link the base code does the
right thing


u32 ethtool_op_get_link(struct net_device *dev)
{
	return netif_carrier_ok(dev) ? 1 : 0;
}



Doing set_mac, change_mtu and ethtool_ops in virtio_user should be possible
but probably not implemented.