Linux Virtualization - Oct 2023 - [PATCH vfio 10/11] vfio/virtio: Expose admin commands over virtio device

> From: Jason Gunthorpe <jgg at nvidia.com>
> Sent: Tuesday, October 10, 2023 9:37 PM
> 
> On Tue, Oct 10, 2023 at 12:03:29PM -0400, Michael S. Tsirkin wrote:
> > On Tue, Oct 10, 2023 at 12:59:37PM -0300, Jason Gunthorpe wrote:
> > > On Tue, Oct 10, 2023 at 11:14:56AM -0400, Michael S. Tsirkin
wrote:
> > >
> > > > I suggest 3 but call it on the VF. commands will switch to
PF
> > > > internally as needed. For example, intel might be interested
in
> > > > exposing admin commands through a memory BAR of VF itself.
If in the future if one does admin command on the VF memory BAR, there is no
need of cast either.
vfio-virtio-pci driver can do on the pci vf device directly.

(though per VF memory registers would be anti-scale design for real hw; to
discuss in other forum).

On Tue, Oct 10, 2023 at 04:21:15PM +0000, Parav Pandit
wrote:
> 
> > From: Jason Gunthorpe <jgg at nvidia.com>
> > Sent: Tuesday, October 10, 2023 9:37 PM
> > 
> > On Tue, Oct 10, 2023 at 12:03:29PM -0400, Michael S. Tsirkin wrote:
> > > On Tue, Oct 10, 2023 at 12:59:37PM -0300, Jason Gunthorpe wrote:
> > > > On Tue, Oct 10, 2023 at 11:14:56AM -0400, Michael S. Tsirkin
wrote:
> > > >
> > > > > I suggest 3 but call it on the VF. commands will switch
to PF
> > > > > internally as needed. For example, intel might be
interested in
> > > > > exposing admin commands through a memory BAR of VF
itself.
> 
> If in the future if one does admin command on the VF memory BAR, there is
no need of cast either.
> vfio-virtio-pci driver can do on the pci vf device directly.
this is why I want the API to get the VF pci device as a parameter.
I don't get what is cyclic about it, yet.
> (though per VF memory registers would be anti-scale design for real hw; to
discuss in other forum).
up to hardware vendor really.