Re: [RFC 7/7] vfio: Add vfio_register_pasid_iommu_dev()

[Yi Liu]

On 2023/11/16 13:12, Cao, Yahui wrote:
> On 10/9/2023 4:51 PM, Yi Liu wrote:
> > From: Kevin Tian<kevin.tian@xxxxxxxxx>
> >
> > This adds vfio_register_pasid_iommu_dev() for device driver to register
> > virtual devices which are isolated per PASID in physical IOMMU. The major
> > usage is for the SIOV devices which allows device driver to tag the DMAs
> > out of virtual devices within it with different PASIDs.
> >
> > For a given vfio device, VFIO core creates both group user interface and
> > device user interface (device cdev) if configured. However, for the virtual
> > devices backed by PASID of the device, VFIO core shall only create device
> > user interface as there is no plan to support such devices in the legacy
> > vfio_iommu drivers which is a must if creating group user interface for
> > such virtual devices. This introduces a VFIO_PASID_IOMMU group type for
> > the device driver to register PASID virtual devices, and provides a wrapper
> > API for it. In particular no iommu group (neither fake group or real group)
> > exists per PASID, hence no group interface for this type.
> >
> > Signed-off-by: Kevin Tian<kevin.tian@xxxxxxxxx>
> > Signed-off-by: Yi Liu<yi.l.liu@xxxxxxxxx>
> > ---
> >   drivers/vfio/group.c     | 18 ++++++++++++++++++
> >   drivers/vfio/vfio.h      |  8 ++++++++
> >   drivers/vfio/vfio_main.c | 10 ++++++++++
> >   include/linux/vfio.h     |  1 +
> >   4 files changed, 37 insertions(+)
> >
> > ...
> > ...
> > +/*
> > + * Register a virtual device with IOMMU pasid protection. The user of
> > + * this device can trigger DMA as long as all of its outgoing DMAs are
> > + * always tagged with a pasid.
> > + */
> > +int vfio_register_pasid_iommu_dev(struct vfio_device *device)
> > +{
> > +    return __vfio_register_dev(device, VFIO_PASID_IOMMU);
> > +}
> > +
>
>
> Missing symbol export here.
fixed.

--
Regards,
Yi Liu