vfio/container: Move vfio_container_destroy() to an instance_finalize() handler

vfio_container_destroy() clears the resources allocated
VFIOContainerBase object. Now that VFIOContainerBase is a QOM object,
add an instance_finalize() handler to do the cleanup. It will be
called through object_unref().

Suggested-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>

hw/vfio/container-base.c

@@ -83,8 +83,9 @@ int vfio_container_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
                                                errp);
 }
 
-void vfio_container_destroy(VFIOContainerBase *bcontainer)
+static void vfio_container_instance_finalize(Object *obj)
 {
+    VFIOContainerBase *bcontainer = VFIO_IOMMU(obj);
     VFIOGuestIOMMU *giommu, *tmp;
 
     QLIST_REMOVE(bcontainer, next);
@@ -116,6 +117,7 @@ static const TypeInfo types[] = {
         .name = TYPE_VFIO_IOMMU,
         .parent = TYPE_OBJECT,
         .instance_init = vfio_container_instance_init,
+        .instance_finalize = vfio_container_instance_finalize,
         .instance_size = sizeof(VFIOContainerBase),
         .class_size = sizeof(VFIOIOMMUClass),
         .abstract = true,

hw/vfio/container.c

@@ -712,8 +712,6 @@ static void vfio_disconnect_container(VFIOGroup *group)
     if (QLIST_EMPTY(&container->group_list)) {
         VFIOAddressSpace *space = bcontainer->space;
 
-        vfio_container_destroy(bcontainer);
-
         trace_vfio_disconnect_container(container->fd);
         vfio_cpr_unregister_container(bcontainer);
         close(container->fd);

hw/vfio/iommufd.c

@@ -237,7 +237,6 @@ static void iommufd_cdev_container_destroy(VFIOIOMMUFDContainer *container)
         return;
     }
     memory_listener_unregister(&bcontainer->listener);
-    vfio_container_destroy(bcontainer);
     iommufd_backend_free_id(container->be, container->ioas_id);
     object_unref(container);
 }

include/hw/vfio/vfio-container-base.h

@@ -86,9 +86,6 @@ int vfio_container_set_dirty_page_tracking(VFIOContainerBase *bcontainer,
 int vfio_container_query_dirty_bitmap(const VFIOContainerBase *bcontainer,
                    VFIOBitmap *vbmap, hwaddr iova, hwaddr size, Error **errp);
 
-void vfio_container_destroy(VFIOContainerBase *bcontainer);
-
-
 #define TYPE_VFIO_IOMMU "vfio-iommu"
 #define TYPE_VFIO_IOMMU_LEGACY TYPE_VFIO_IOMMU "-legacy"
 #define TYPE_VFIO_IOMMU_SPAPR TYPE_VFIO_IOMMU "-spapr"