RE: [PATCH v12 06/10] vfio/region: Add a helper to get VFIO region from memory region

["Kasireddy, Vivek" <vivek.kasireddy@intel.com>]

> Subject: Re: [PATCH v12 06/10] vfio/region: Add a helper to get VFIO
> region from memory region
> 
> On 3/19/26 06:15, Vivek Kasireddy wrote:
> > Having a way to get the VFIO region associated with a memory region
> > is helpful in various scenarios. For example, this capability can
> > be useful in retrieving the region info such as index and offset
> > needed for mapping a part of a VFIO region or creating a dmabuf.
> >
> > Cc: Alex Williamson <alex@shazbot.org>
> > Cc: Cédric Le Goater <clg@redhat.com>
> > Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
> > ---
> >   hw/vfio/vfio-region.h | 10 ++++++++++
> >   hw/vfio/region.c      | 11 +++++++++++
> >   2 files changed, 21 insertions(+)
> >
> > diff --git a/hw/vfio/vfio-region.h b/hw/vfio/vfio-region.h
> > index 9b21d4ee5b..3dd47f77f6 100644
> > --- a/hw/vfio/vfio-region.h
> > +++ b/hw/vfio/vfio-region.h
> > @@ -45,4 +45,14 @@ void vfio_region_unmap(VFIORegion *region);
> >   void vfio_region_exit(VFIORegion *region);
> >   void vfio_region_finalize(VFIORegion *region);
> >
> > +/**
> > + * Return the VFIO region associated with a given MemoryRegion.
> This can
> > + * be useful in retrieving region info such as index and offset.
> > + *
> > + * @mr: MemoryRegion to use
> > + *
> > + * Returns the region or NULL on error.
> > + */
> > +void *vfio_get_region_from_mr(MemoryRegion *mr);
> > +
> >   #endif /* HW_VFIO_REGION_H */
> > diff --git a/hw/vfio/region.c b/hw/vfio/region.c
> > index 47fdc2df34..9d7ac339c9 100644
> > --- a/hw/vfio/region.c
> > +++ b/hw/vfio/region.c
> > @@ -539,3 +539,14 @@ void
> vfio_region_mmaps_set_enabled(VFIORegion *region, bool enabled)
> >
> trace_vfio_region_mmaps_set_enabled(memory_region_name(region-
> >mem),
> >                                           enabled);
> >   }
> > +
> > +void *vfio_get_region_from_mr(MemoryRegion *mr)
> 
> can we return a "VFIORegion *" ?
Sure, I'll make the change.

Thanks,
Vivek

> 
> Thanks,
> 
> C.
> 
> > +{
> > +    while (mr->container) {
> > +        if (mr->ops == &vfio_region_ops) {
> > +            return mr->opaque;
> > +        }
> > +        mr = mr->container;
> > +    }
> > +    return NULL;
> > +}