RE: [PATCH v2 02/11] iommu: Add nested domain support

[Tian, Kevin]

> From: Nicolin Chen <nicolinc@xxxxxxxxxx>
> Sent: Saturday, May 20, 2023 2:49 AM
> 
> On Fri, May 19, 2023 at 08:51:21AM +0000, Tian, Kevin wrote:
> 
> > > @@ -346,6 +350,10 @@ struct iommu_ops {
> > >   * @iotlb_sync_map: Sync mappings created recently using @map to the
> > > hardware
> > >   * @iotlb_sync: Flush all queued ranges from the hardware TLBs and
> empty
> > > flush
> > >   *            queue
> > > + * @cache_invalidate_user: Flush hardware TLBs caching user space IO
> > > mappings
> > > + * @cache_invalidate_user_data_len: Defined length of input user data
> for
> > > the
> > > + *                                  cache_invalidate_user op, being sizeof the
> > > + *                                  structure in include/uapi/linux/iommufd.h
> >
> > same as comment to last patch, can this be merged with @hw_info?
> 
> I think it's better to keep them separate, since this is added
> in struct iommu_domain_ops, given it is domain/hwpt specific,
> while the hw_info is in struct iommu_ops?
> 

Just be curious whether there are real examples in which the data
len might be different upon the hwpt type...