vfio/common: Store the parent container in VFIODevice

let's store the parent contaienr within the VFIODevice.
This simplifies the logic in vfio_viommu_preset() and
brings the benefice to hide the group specificity which
is useful for IOMMUFD migration.

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

1 files changed, 7 insertions, 1 deletions

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index ef9dc7c747..55f8a113ea 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -184,7 +184,7 @@ void vfio_unblock_multiple_devices_migration(void)
 
 bool vfio_viommu_preset(VFIODevice *vbasedev)
 {
-    return vbasedev->group->container->space->as != &address_space_memory;
+    return vbasedev->container->space->as != &address_space_memory;
 }
 
 static void vfio_set_migration_error(int err)
@@ -2655,6 +2655,7 @@ int vfio_attach_device(char *name, VFIODevice *vbasedev,
     }
 
     container = group->container;
+    vbasedev->container = container;
     QLIST_INSERT_HEAD(&container->device_list, vbasedev, container_next);
 
     return ret;
@@ -2664,7 +2665,12 @@ void vfio_detach_device(VFIODevice *vbasedev)
 {
     VFIOGroup *group = vbasedev->group;
 
+    if (!vbasedev->container) {
+        return;
+    }
+
     QLIST_REMOVE(vbasedev, container_next);
+    vbasedev->container = NULL;
     trace_vfio_detach_device(vbasedev->name, group->groupid);
     vfio_put_base_device(vbasedev);
     vfio_put_group(group);