Re: [PATCH V2 3/5] vDPA: introduce vDPA bus

On Thu, Feb 13, 2020 at 11:34:10AM +0800, Jason Wang wrote:

quoted

  You have dev, type or
class to choose from. Type is rarely used and doesn't seem to be used
by vdpa, so class seems the right choice

Jason

Yes, but my understanding is class and bus are mutually exclusive. So we
can't add a class to a device which is already attached on a bus.

While I suppose there are variations, typically 'class' devices are
user facing things and 'bus' devices are internal facing (ie like a
PCI device)

So why is this using a bus? VDPA is a user facing object, so the
driver should create a class vhost_vdpa device directly, and that
driver should live in the drivers/vhost/ directory.

For the PCI VF case this driver would bind to a PCI device like
everything else

For our future SF/ADI cases the driver would bind to some
SF/ADI/whatever device on a bus.

I don't see a reason for VDPA to be creating busses..

Jason