> From: Nicolin Chen <nicol...@nvidia.com> > Sent: Friday, June 17, 2022 6:41 AM > > > ... > > > - if (resv_msi) { > > > + if (resv_msi && !domain->msi_cookie) { > > > ret = iommu_get_msi_cookie(domain->domain, > > > resv_msi_base); > > > if (ret && ret != -ENODEV) > > > goto out_detach; > > > + domain->msi_cookie = true; > > > } > > > > why not moving to alloc_attach_domain() then no need for the new > > domain field? It's required only when a new domain is allocated. > > When reusing an existing domain that doesn't have an msi_cookie, > we can do iommu_get_msi_cookie() if resv_msi is found. So it is > not limited to a new domain.
Looks msi_cookie requirement is per platform (currently only for smmu. see arm_smmu_get_resv_regions()). If there is no mixed case then above check is not required. But let's hear whether Robin has a different thought here. > > > ... > > > - if (list_empty(&domain->group_list)) { > > > - if (list_is_singular(&iommu->domain_list)) { > > > - if (list_empty(&iommu- > > > >emulated_iommu_groups)) { > > > - WARN_ON(iommu->notifier.head); > > > - > > > vfio_iommu_unmap_unpin_all(iommu); > > > - } else { > > > - > > > vfio_iommu_unmap_unpin_reaccount(iommu); > > > - } > > > - } > > > - iommu_domain_free(domain->domain); > > > - list_del(&domain->next); > > > - kfree(domain); > > > - vfio_iommu_aper_expand(iommu, &iova_copy); > > > > Previously the aperture is adjusted when a domain is freed... > > > > > - vfio_update_pgsize_bitmap(iommu); > > > - } > > > - /* > > > - * Removal of a group without dirty tracking may allow > > > - * the iommu scope to be promoted. > > > - */ > > > - if (!group->pinned_page_dirty_scope) { > > > - iommu->num_non_pinned_groups--; > > > - if (iommu->dirty_page_tracking) > > > - vfio_iommu_populate_bitmap_full(iommu); > > > - } > > > + vfio_iommu_detach_destroy_domain(domain, iommu, > > > group); > > > kfree(group); > > > break; > > > } > > > > > > + vfio_iommu_aper_expand(iommu, &iova_copy); > > > > but now it's done for every group detach. The aperture is decided > > by domain geometry which is not affected by attached groups. > > Yea, I've noticed this part. Actually Jason did this change for > simplicity, and I think it'd be safe to do so? Perhaps detach_destroy() can return a Boolean to indicate whether a domain is destroyed. _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu