vfio: remove the unused mdev iommu hook

The iommu_device field in struct mdev_device has never been used
since it was added more than 2 years ago.

This is a manual revert of commit 7bd50f0cd2
("vfio/type1: Add domain at(de)taching group helpers").

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Link: https://lore.kernel.org/r/20210924155705.4258-11-hch@lst.de
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

1 files changed, 26 insertions, 107 deletions

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 2e51e4390c15..42a6be1fb726 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -114,7 +114,6 @@ struct vfio_batch {
 struct vfio_iommu_group {
 	struct iommu_group	*iommu_group;
 	struct list_head	next;
-	bool			mdev_group;	/* An mdev group */
 	bool			pinned_page_dirty_scope;
 };
 
@@ -1935,61 +1934,6 @@ static bool vfio_iommu_has_sw_msi(struct list_head *group_resv_regions,
 	return ret;
 }
 
-static int vfio_mdev_attach_domain(struct device *dev, void *data)
-{
-	struct mdev_device *mdev = to_mdev_device(dev);
-	struct iommu_domain *domain = data;
-	struct device *iommu_device;
-
-	iommu_device = mdev_get_iommu_device(mdev);
-	if (iommu_device) {
-		if (iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX))
-			return iommu_aux_attach_device(domain, iommu_device);
-		else
-			return iommu_attach_device(domain, iommu_device);
-	}
-
-	return -EINVAL;
-}
-
-static int vfio_mdev_detach_domain(struct device *dev, void *data)
-{
-	struct mdev_device *mdev = to_mdev_device(dev);
-	struct iommu_domain *domain = data;
-	struct device *iommu_device;
-
-	iommu_device = mdev_get_iommu_device(mdev);
-	if (iommu_device) {
-		if (iommu_dev_feature_enabled(iommu_device, IOMMU_DEV_FEAT_AUX))
-			iommu_aux_detach_device(domain, iommu_device);
-		else
-			iommu_detach_device(domain, iommu_device);
-	}
-
-	return 0;
-}
-
-static int vfio_iommu_attach_group(struct vfio_domain *domain,
-				   struct vfio_iommu_group *group)
-{
-	if (group->mdev_group)
-		return iommu_group_for_each_dev(group->iommu_group,
-						domain->domain,
-						vfio_mdev_attach_domain);
-	else
-		return iommu_attach_group(domain->domain, group->iommu_group);
-}
-
-static void vfio_iommu_detach_group(struct vfio_domain *domain,
-				    struct vfio_iommu_group *group)
-{
-	if (group->mdev_group)
-		iommu_group_for_each_dev(group->iommu_group, domain->domain,
-					 vfio_mdev_detach_domain);
-	else
-		iommu_detach_group(domain->domain, group->iommu_group);
-}
-
 static bool vfio_bus_is_mdev(struct bus_type *bus)
 {
 	struct bus_type *mdev_bus;
@@ -2004,20 +1948,6 @@ static bool vfio_bus_is_mdev(struct bus_type *bus)
 	return ret;
 }
 
-static int vfio_mdev_iommu_device(struct device *dev, void *data)
-{
-	struct mdev_device *mdev = to_mdev_device(dev);
-	struct device **old = data, *new;
-
-	new = mdev_get_iommu_device(mdev);
-	if (!new || (*old && *old != new))
-		return -EINVAL;
-
-	*old = new;
-
-	return 0;
-}
-
 /*
  * This is a helper function to insert an address range to iova list.
  * The list is initially created with a single entry corresponding to
@@ -2278,38 +2208,25 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
 		goto out_free;
 
 	if (vfio_bus_is_mdev(bus)) {
-		struct device *iommu_device = NULL;
-
-		group->mdev_group = true;
-
-		/* Determine the isolation type */
-		ret = iommu_group_for_each_dev(iommu_group, &iommu_device,
-					       vfio_mdev_iommu_device);
-		if (ret || !iommu_device) {
-			if (!iommu->external_domain) {
-				INIT_LIST_HEAD(&domain->group_list);
-				iommu->external_domain = domain;
-				vfio_update_pgsize_bitmap(iommu);
-			} else {
-				kfree(domain);
-			}
-
-			list_add(&group->next,
-				 &iommu->external_domain->group_list);
-			/*
-			 * Non-iommu backed group cannot dirty memory directly,
-			 * it can only use interfaces that provide dirty
-			 * tracking.
-			 * The iommu scope can only be promoted with the
-			 * addition of a dirty tracking group.
-			 */
-			group->pinned_page_dirty_scope = true;
-			mutex_unlock(&iommu->lock);
-
-			return 0;
+		if (!iommu->external_domain) {
+			INIT_LIST_HEAD(&domain->group_list);
+			iommu->external_domain = domain;
+			vfio_update_pgsize_bitmap(iommu);
+		} else {
+			kfree(domain);
 		}
 
-		bus = iommu_device->bus;
+		list_add(&group->next, &iommu->external_domain->group_list);
+		/*
+		 * Non-iommu backed group cannot dirty memory directly, it can
+		 * only use interfaces that provide dirty tracking.
+		 * The iommu scope can only be promoted with the addition of a
+		 * dirty tracking group.
+		 */
+		group->pinned_page_dirty_scope = true;
+		mutex_unlock(&iommu->lock);
+
+		return 0;
 	}
 
 	domain->domain = iommu_domain_alloc(bus);
@@ -2324,7 +2241,7 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
 			goto out_domain;
 	}
 
-	ret = vfio_iommu_attach_group(domain, group);
+	ret = iommu_attach_group(domain->domain, group->iommu_group);
 	if (ret)
 		goto out_domain;
 
@@ -2391,15 +2308,17 @@ static int vfio_iommu_type1_attach_group(void *iommu_data,
 	list_for_each_entry(d, &iommu->domain_list, next) {
 		if (d->domain->ops == domain->domain->ops &&
 		    d->prot == domain->prot) {
-			vfio_iommu_detach_group(domain, group);
-			if (!vfio_iommu_attach_group(d, group)) {
+			iommu_detach_group(domain->domain, group->iommu_group);
+			if (!iommu_attach_group(d->domain,
+						group->iommu_group)) {
 				list_add(&group->next, &d->group_list);
 				iommu_domain_free(domain->domain);
 				kfree(domain);
 				goto done;
 			}
 
-			ret = vfio_iommu_attach_group(domain, group);
+			ret = iommu_attach_group(domain->domain,
+						 group->iommu_group);
 			if (ret)
 				goto out_domain;
 		}
@@ -2436,7 +2355,7 @@ done:
 	return 0;
 
 out_detach:
-	vfio_iommu_detach_group(domain, group);
+	iommu_detach_group(domain->domain, group->iommu_group);
 out_domain:
 	iommu_domain_free(domain->domain);
 	vfio_iommu_iova_free(&iova_copy);
@@ -2601,7 +2520,7 @@ static void vfio_iommu_type1_detach_group(void *iommu_data,
 		if (!group)
 			continue;
 
-		vfio_iommu_detach_group(domain, group);
+		iommu_detach_group(domain->domain, group->iommu_group);
 		update_dirty_scope = !group->pinned_page_dirty_scope;
 		list_del(&group->next);
 		kfree(group);
@@ -2689,7 +2608,7 @@ static void vfio_release_domain(struct vfio_domain *domain, bool external)
 	list_for_each_entry_safe(group, group_tmp,
 				 &domain->group_list, next) {
 		if (!external)
-			vfio_iommu_detach_group(domain, group);
+			iommu_detach_group(domain->domain, group->iommu_group);
 		list_del(&group->next);
 		kfree(group);
 	}