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Date:   Mon, 1 Mar 2021 20:29:22 -0400
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Dave Jiang <dave.jiang@intel.com>
CC:     <alex.williamson@redhat.com>, <kwankhede@nvidia.com>,
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Subject: Re: [PATCH v5 05/14] vfio/mdev: idxd: add basic mdev registration
 and helper functions
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On Mon, Mar 01, 2021 at 05:23:47PM -0700, Dave Jiang wrote:
> 
> So after looking at the code in vfio_pci_intrs.c, I agree that the set_irqs
> code between VFIO_PCI and this driver can be made in common. Given that Alex
> doesn't want a vfio_pci device embedded in the driver, 

idxd isn't a vfio_pci so it would be improper to do something like
that here anyhow.

> I think we'll need some sort of generic VFIO device that can be used
> from the vfio_pci side and vfio_mdev side to pass down in order to
> have common support library functions. 

Why do you need more layers?

Just make some helper functions to manage this and build them into
their own struct and function family. All this needs is some callback
to for the end driver to hook in the raw device programming and some
entry points to direct the emulation access to the module.

It should be fully self contained and completely unrelated to vfio_pci

Jason