diff --git a/src/nm-ip4-config.c b/src/nm-ip4-config.c
index 26545aa1b..07f820a75 100644
--- a/src/nm-ip4-config.c
+++ b/src/nm-ip4-config.c
@@ -35,11 +35,7 @@
 
 #include "nmdbus-ip4-config.h"
 
-G_DEFINE_TYPE (NMIP4Config, nm_ip4_config, NM_TYPE_EXPORTED_OBJECT)
-
-#define NM_IP4_CONFIG_GET_PRIVATE(o) ((o)->priv)
-
-typedef struct _NMIP4ConfigPrivate {
+typedef struct {
 	gboolean never_default;
 	guint32 gateway;
 	gboolean has_gateway;
@@ -60,6 +56,25 @@ typedef struct _NMIP4ConfigPrivate {
 	gboolean metered;
 } NMIP4ConfigPrivate;
 
+struct _NMIP4Config {
+	NMExportedObject parent;
+	NMIP4ConfigPrivate _priv;
+};
+
+struct _NMIP4ConfigClass {
+	NMExportedObjectClass parent;
+};
+
+G_DEFINE_TYPE (NMIP4Config, nm_ip4_config, NM_TYPE_EXPORTED_OBJECT)
+
+#define NM_IP4_CONFIG_GET_PRIVATE(o) \
+	({ \
+		const NMIP4ConfigPrivate *_priv = &(o)->_priv; \
+		\
+		/* cast away the const. */ \
+		((NMIP4ConfigPrivate *) _priv); \
+	})
+
 /* internal guint32 are assigned to gobject properties of type uint. Ensure, that uint is large enough */
 G_STATIC_ASSERT (sizeof (uint) >= sizeof (guint32));
 G_STATIC_ASSERT (G_MAXUINT >= 0xFFFFFFFF);
@@ -2199,10 +2214,7 @@ nm_ip4_config_equal (const NMIP4Config *a, const NMIP4Config *b)
 static void
 nm_ip4_config_init (NMIP4Config *config)
 {
-	NMIP4ConfigPrivate *priv;
-
-	priv = G_TYPE_INSTANCE_GET_PRIVATE (config, NM_TYPE_IP4_CONFIG, NMIP4ConfigPrivate);
-	config->priv = priv;
+	NMIP4ConfigPrivate *priv = NM_IP4_CONFIG_GET_PRIVATE (config);
 
 	priv->addresses = g_array_new (FALSE, FALSE, sizeof (NMPlatformIP4Address));
 	priv->routes = g_array_new (FALSE, FALSE, sizeof (NMPlatformIP4Route));
@@ -2424,8 +2436,6 @@ nm_ip4_config_class_init (NMIP4ConfigClass *config_class)
 	GObjectClass *object_class = G_OBJECT_CLASS (config_class);
 	NMExportedObjectClass *exported_object_class = NM_EXPORTED_OBJECT_CLASS (config_class);
 
-	g_type_class_add_private (config_class, sizeof (NMIP4ConfigPrivate));
-
 	exported_object_class->export_path = NM_DBUS_PATH "/IP4Config/%u";
 
 	object_class->get_property = get_property;
diff --git a/src/nm-ip4-config.h b/src/nm-ip4-config.h
index b1a576874..6eb1aed8b 100644
--- a/src/nm-ip4-config.h
+++ b/src/nm-ip4-config.h
@@ -31,18 +31,7 @@
 #define NM_IS_IP4_CONFIG_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), NM_TYPE_IP4_CONFIG))
 #define NM_IP4_CONFIG_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), NM_TYPE_IP4_CONFIG, NMIP4ConfigClass))
 
-struct _NMIP4ConfigPrivate;
-
-struct _NMIP4Config {
-	NMExportedObject parent;
-
-	/* private */
-	struct _NMIP4ConfigPrivate *priv;
-};
-
-typedef struct {
-	NMExportedObjectClass parent;
-} NMIP4ConfigClass;
+typedef struct _NMIP4ConfigClass NMIP4ConfigClass;
 
 /* internal */
 #define NM_IP4_CONFIG_IFINDEX "ifindex"
diff --git a/src/nm-ip6-config.c b/src/nm-ip6-config.c
index 790f684cd..ed33bdb36 100644
--- a/src/nm-ip6-config.c
+++ b/src/nm-ip6-config.c
@@ -34,11 +34,7 @@
 
 #include "nmdbus-ip6-config.h"
 
-G_DEFINE_TYPE (NMIP6Config, nm_ip6_config, NM_TYPE_EXPORTED_OBJECT)
-
-#define NM_IP6_CONFIG_GET_PRIVATE(o) ((o)->priv)
-
-typedef struct _NMIP6ConfigPrivate {
+typedef struct {
 	gboolean never_default;
 	struct in6_addr gateway;
 	GArray *addresses;
@@ -52,6 +48,24 @@ typedef struct _NMIP6ConfigPrivate {
 	gint64 route_metric;
 } NMIP6ConfigPrivate;
 
+struct _NMIP6Config {
+	NMExportedObject parent;
+	NMIP6ConfigPrivate _priv;
+};
+
+struct _NMIP6ConfigClass {
+	NMExportedObjectClass parent;
+};
+
+G_DEFINE_TYPE (NMIP6Config, nm_ip6_config, NM_TYPE_EXPORTED_OBJECT)
+
+#define NM_IP6_CONFIG_GET_PRIVATE(o) \
+	({ \
+		const NMIP6ConfigPrivate *_priv = &(o)->_priv; \
+		\
+		/* cast away the const. */ \
+		((NMIP6ConfigPrivate *) _priv); \
+	})
 
 NM_GOBJECT_PROPERTIES_DEFINE (NMIP6Config,
 	PROP_IFINDEX,
@@ -1887,10 +1901,7 @@ nm_ip6_config_equal (const NMIP6Config *a, const NMIP6Config *b)
 static void
 nm_ip6_config_init (NMIP6Config *config)
 {
-	NMIP6ConfigPrivate *priv;
-
-	priv = G_TYPE_INSTANCE_GET_PRIVATE (config, NM_TYPE_IP6_CONFIG, NMIP6ConfigPrivate);
-	config->priv = priv;
+	NMIP6ConfigPrivate *priv = NM_IP6_CONFIG_GET_PRIVATE (config);
 
 	priv->addresses = g_array_new (FALSE, TRUE, sizeof (NMPlatformIP6Address));
 	priv->routes = g_array_new (FALSE, TRUE, sizeof (NMPlatformIP6Route));
@@ -2110,8 +2121,6 @@ nm_ip6_config_class_init (NMIP6ConfigClass *config_class)
 	GObjectClass *object_class = G_OBJECT_CLASS (config_class);
 	NMExportedObjectClass *exported_object_class = NM_EXPORTED_OBJECT_CLASS (config_class);
 
-	g_type_class_add_private (config_class, sizeof (NMIP6ConfigPrivate));
-
 	exported_object_class->export_path = NM_DBUS_PATH "/IP6Config/%u";
 
 	/* virtual methods */
diff --git a/src/nm-ip6-config.h b/src/nm-ip6-config.h
index 5e66d500e..85b75db0e 100644
--- a/src/nm-ip6-config.h
+++ b/src/nm-ip6-config.h
@@ -33,18 +33,7 @@
 #define NM_IS_IP6_CONFIG_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), NM_TYPE_IP6_CONFIG))
 #define NM_IP6_CONFIG_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), NM_TYPE_IP6_CONFIG, NMIP6ConfigClass))
 
-struct _NMIP6ConfigPrivate;
-
-struct _NMIP6Config {
-	NMExportedObject parent;
-
-	/* private */
-	struct _NMIP6ConfigPrivate *priv;
-};
-
-typedef struct {
-	NMExportedObjectClass parent;
-} NMIP6ConfigClass;
+typedef struct _NMIP6ConfigClass NMIP6ConfigClass;
 
 /* internal */
 #define NM_IP6_CONFIG_IFINDEX "ifindex"