vfio/container: Introduce vfio_address_space_insert()

It prepares ground for a future change initializing the 'space' pointer
of VFIOContainerBase. The goal is to replace vfio_container_init() by
an .instance_init() handler when VFIOContainerBase is QOMified.

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/common.c

@@ -1508,6 +1508,12 @@ void vfio_put_address_space(VFIOAddressSpace *space)
     }
 }
 
+void vfio_address_space_insert(VFIOAddressSpace *space,
+                               VFIOContainerBase *bcontainer)
+{
+    QLIST_INSERT_HEAD(&space->containers, bcontainer, next);
+}
+
 struct vfio_device_info *vfio_get_device_info(int fd)
 {
     struct vfio_device_info *info;

hw/vfio/container.c

@@ -637,7 +637,7 @@ static bool vfio_connect_container(VFIOGroup *group, AddressSpace *as,
     vfio_kvm_device_add_group(group);
 
     QLIST_INIT(&container->group_list);
-    QLIST_INSERT_HEAD(&space->containers, bcontainer, next);
+    vfio_address_space_insert(space, bcontainer);
 
     group->container = container;
     QLIST_INSERT_HEAD(&container->group_list, group, container_next);

hw/vfio/iommufd.c

@@ -358,7 +358,7 @@ static bool iommufd_cdev_attach(const char *name, VFIODevice *vbasedev,
 
     bcontainer = &container->bcontainer;
     vfio_container_init(bcontainer, space, iommufd_vioc);
-    QLIST_INSERT_HEAD(&space->containers, bcontainer, next);
+    vfio_address_space_insert(space, bcontainer);
 
     if (!iommufd_cdev_attach_container(vbasedev, container, errp)) {
         goto err_attach_container;

include/hw/vfio/vfio-common.h

@@ -206,6 +206,8 @@ typedef struct VFIODisplay {
 
 VFIOAddressSpace *vfio_get_address_space(AddressSpace *as);
 void vfio_put_address_space(VFIOAddressSpace *space);
+void vfio_address_space_insert(VFIOAddressSpace *space,
+                               VFIOContainerBase *bcontainer);
 
 void vfio_disable_irqindex(VFIODevice *vbasedev, int index);
 void vfio_unmask_single_irqindex(VFIODevice *vbasedev, int index);