Re: [PATCH v3] vfio: Support VFIO_NOIOMMU with iommufd

[Jason Gunthorpe <jgg@nvidia.com>]

On Wed, Jan 18, 2023 at 11:58:31AM -0700, Alex Williamson wrote:
> On Wed, 18 Jan 2023 13:50:28 -0400
> Jason Gunthorpe <jgg@nvidia.com> wrote:
> > diff --git a/drivers/vfio/vfio.h b/drivers/vfio/vfio.h
> > index f8219a438bfbf5..9e94abcf8ee1a8 100644
> > --- a/drivers/vfio/vfio.h
> > +++ b/drivers/vfio/vfio.h
> > @@ -10,10 +10,10 @@
> >  #include <linux/device.h>
> >  #include <linux/cdev.h>
> >  #include <linux/module.h>
> > +#include <linux/vfio.h>
> >  
> >  struct iommufd_ctx;
> >  struct iommu_group;
> > -struct vfio_device;
> >  struct vfio_container;
> >  
> >  void vfio_device_put_registration(struct vfio_device *device);
> > @@ -88,6 +88,12 @@ bool vfio_device_has_container(struct vfio_device *device);
> >  int __init vfio_group_init(void);
> >  void vfio_group_cleanup(void);
> >  
> > +static inline bool vfio_device_is_noiommu(struct vfio_device *vdev)
> > +{
> > +	return IS_ENABLED(CONFIG_VFIO_NOIOMMU) &&
> > +	       vdev->group->type == VFIO_NO_IOMMU;
> > +}
> 
> 
> What about:
> 
> static inline bool vfio_group_type_is_noiommu(struct vfio_group *group)

For Yi's series to work we can't refer to device->group outside
group.c - it should be compiled out entirely in some kconfigs.

So this function is the right signature for the call sites I added

> which would allow us to pickup the group.c use with only extending the
> callers here as s/vdev/vdev->group/?  

I think this would an OK mini-cleanup for group.c..

Are you OK with it as is?

Jason