Tian, Kevin
2022-Jun-08 08:35 UTC
[PATCH 4/5] vfio/iommu_type1: Clean up update_dirty_scope in detach_group()
> From: Nicolin Chen > Sent: Monday, June 6, 2022 2:19 PM > > All devices in emulated_iommu_groups have pinned_page_dirty_scope > set, so the update_dirty_scope in the first list_for_each_entry > is always false. Clean it up, and move the "if update_dirty_scope" > part from the detach_group_done routine to the domain_list part. > > Rename the "detach_group_done" goto label accordingly. > > Suggested-by: Jason Gunthorpe <jgg at nvidia.com> > Signed-off-by: Nicolin Chen <nicolinc at nvidia.com> > --- > drivers/vfio/vfio_iommu_type1.c | 27 ++++++++++++--------------- > 1 file changed, 12 insertions(+), 15 deletions(-) > > diff --git a/drivers/vfio/vfio_iommu_type1.c > b/drivers/vfio/vfio_iommu_type1.c > index f4e3b423a453..b45b1cc118ef 100644 > --- a/drivers/vfio/vfio_iommu_type1.c > +++ b/drivers/vfio/vfio_iommu_type1.c > @@ -2463,14 +2463,12 @@ static void > vfio_iommu_type1_detach_group(void *iommu_data, > struct vfio_iommu *iommu = iommu_data; > struct vfio_domain *domain; > struct vfio_iommu_group *group; > - bool update_dirty_scope = false; > LIST_HEAD(iova_copy); > > mutex_lock(&iommu->lock); > list_for_each_entry(group, &iommu->emulated_iommu_groups, > next) { > if (group->iommu_group != iommu_group) > continue; > - update_dirty_scope = !group->pinned_page_dirty_scope; > list_del(&group->next); > kfree(group); > > @@ -2479,7 +2477,7 @@ static void vfio_iommu_type1_detach_group(void > *iommu_data, > WARN_ON(iommu->notifier.head); > vfio_iommu_unmap_unpin_all(iommu); > } > - goto detach_group_done; > + goto out_unlock; > } > > /* > @@ -2495,9 +2493,7 @@ static void vfio_iommu_type1_detach_group(void > *iommu_data, > continue; > > iommu_detach_group(domain->domain, group- > >iommu_group); > - update_dirty_scope = !group->pinned_page_dirty_scope; > list_del(&group->next); > - kfree(group); > /* > * Group ownership provides privilege, if the group list is > * empty, the domain goes away. If it's the last domain with > @@ -2519,7 +2515,17 @@ static void vfio_iommu_type1_detach_group(void > *iommu_data, > kfree(domain); > vfio_iommu_aper_expand(iommu, &iova_copy); > 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);This doesn't look correct. The old code decrements num_non_pinned_groups for every detach group without dirty tracking. But now it's only done when the domain is about to be released...> + } > } > + kfree(group); > break; > } > > @@ -2528,16 +2534,7 @@ static void vfio_iommu_type1_detach_group(void > *iommu_data, > else > vfio_iommu_iova_free(&iova_copy); > > -detach_group_done: > - /* > - * Removal of a group without dirty tracking may allow the iommu > scope > - * to be promoted. > - */ > - if (update_dirty_scope) { > - iommu->num_non_pinned_groups--; > - if (iommu->dirty_page_tracking) > - vfio_iommu_populate_bitmap_full(iommu); > - } > +out_unlock: > mutex_unlock(&iommu->lock); > } > > -- > 2.17.1 > > _______________________________________________ > iommu mailing list > iommu at lists.linux-foundation.org > https://lists.linuxfoundation.org/mailman/listinfo/iommu