On Fri, Jul 28, 2023 at 02:55:57PM -0300, Jason Gunthorpe wrote:
> On Mon, Jul 24, 2023 at 04:03:57AM -0700, Yi Liu wrote:
>
> > + switch (pt_obj->type) {
> > + case IOMMUFD_OBJ_IOAS:
> > + ioas = container_of(pt_obj, struct iommufd_ioas, obj);
> > + break;
> > + case IOMMUFD_OBJ_HW_PAGETABLE:
> > + /* pt_id points HWPT only when hwpt_type is !IOMMU_HWPT_TYPE_DEFAULT */
> > + if (cmd->hwpt_type == IOMMU_HWPT_TYPE_DEFAULT) {
> > + rc = -EINVAL;
> > + goto out_put_pt;
> > + }
> > +
> > + parent = container_of(pt_obj, struct iommufd_hw_pagetable, obj);
> > + /*
> > + * Cannot allocate user-managed hwpt linking to auto_created
> > + * hwpt. If the parent hwpt is already a user-managed hwpt,
> > + * don't allocate another user-managed hwpt linking to it.
> > + */
> > + if (parent->auto_domain || parent->parent) {
> > + rc = -EINVAL;
> > + goto out_put_pt;
> > + }
> > + ioas = parent->ioas;
>
> Why do we set ioas here? I would think it should be NULL.
>
> I think it is looking like a mistake to try and re-use
> iommufd_hw_pagetable_alloc() directly for the nested case. It should
> not have a IOAS argument, it should not do enforce_cc, or iopt_*
> functions
>
> So must of the function is removed. Probably better to make a new
> ioas-less function for the nesting case.
OK.
@Yi, along with the PATCH-6 (IOMMU_RESV_SW_MSI), I will rework
on this -- mainly breaking up NESTED hwpt with IOAS.
Thanks
Nic
