RE: [PATCH v1 09/22] vfio/common: check PASID alloc/free availability

[Liu, Yi L]

> From: Peter Xu <address@hidden>
> Sent: Tuesday, March 24, 2020 6:07 AM
> To: Liu, Yi L <address@hidden>
> Subject: Re: [PATCH v1 09/22] vfio/common: check PASID alloc/free availability
> 
> On Sun, Mar 22, 2020 at 05:36:06AM -0700, Liu Yi L wrote:
> 
> [...]
> 
> > @@ -1256,11 +1334,19 @@ static int vfio_init_container(VFIOContainer
> *container, int group_fd,
> >      }
> >
> >      if (iommu_type == VFIO_TYPE1_NESTING_IOMMU) {
> > -        /*
> > -         * TODO: config flags per host IOMMU nesting capability
> > -         * e.g. check if VFIO_TYPE1_NESTING_IOMMU supports PASID
> > -         * alloc/free
> > -         */
> > +        struct vfio_iommu_type1_info_cap_nesting nesting = {
> > +                                         .nesting_capabilities = 0x0,
> > +                                         .stage1_formats = 0, };
> > +
> > +        ret = vfio_get_nesting_iommu_cap(container, &nesting);
> > +        if (ret) {
> > +            error_setg_errno(errp, -ret,
> > +                             "Failed to get nesting iommu cap");
> > +            return ret;
> > +        }
> > +
> > +        flags |= (nesting.nesting_capabilities & VFIO_IOMMU_PASID_REQS) ?
> > +                 HOST_IOMMU_PASID_REQUEST : 0;
> 
> I replied in the previous patch but I forgot to use reply-all...
> 
> Anyway I'll comment again here - I think it'll be slightly better we
> use the previous patch to only offer the vfio specific hooks, and this
> patch to do all the rest including host_iommu_ctx_init() below, which
> will avoid creating the host_iommu_ctx_init().

Got it. Let me do it in next version.

Regards,
Yi Liu