RE: [RFC 03/20] vfio: Add vfio_[un]register_device()

[Tian, Kevin]

> From: Jason Gunthorpe <jgg@xxxxxxxxxx>
> Sent: Thursday, September 23, 2021 7:52 AM
> 
> On Wed, Sep 22, 2021 at 11:45:33PM +0000, Tian, Kevin wrote:
> > > From: Alex Williamson <alex.williamson@xxxxxxxxxx>
> 
> > btw I realized another related piece regarding to the new layout that
> > Jason suggested, which have sys device node include a link to the vfio
> > devnode:
> >
> > 	/sys/bus/pci/devices/DDDD:BB:DD.F/vfio/vfioX/dev
> >
> > This for sure requires specific vfio driver support to get the link
> > established.
> 
> It doesn't. Just set the parent device of the vfio_device's struct
> device to the physical struct device that vfio is already tracking -
> ie the struct device providing the IOMMU. The driver core takes care
> of everything else.
> 

Thanks for correction. So it's still the same try-and-fail model for both 
devices which support iommufd and which do not.