manager: downgrade error message for missing dependencies

At startup the manager tries to create virtual devices without a
specific order and spits warnings when a device can't be realized
because the parent device is not yet created. These failures are not
something the user should worry about because the creation will be
retried when the parent appears.

A better approach is to return an error code from the device's
create_and_realize() telling that it failed because the parent doesn't
exist. In this way, the manager knows that the device isn't ready and
can avoid printing warning messages.

libnm-core/nm-errors.h

@@ -143,6 +143,8 @@ GQuark nm_crypto_error_quark (void);
  *   activation request (eg, the #NMAccessPoint or #NMWimaxNsp) was not
  *   found.
  * @NM_DEVICE_ERROR_VERSION_ID_MISMATCH: the version id did not match.
+ * @NM_DEVICE_ERROR_MISSING_DEPENDENCIES: the requested operation could not
+ *   be completed due to missing dependencies.
  *
  * Device-related errors.
  *
@@ -160,6 +162,7 @@ typedef enum {
 	NM_DEVICE_ERROR_NOT_ALLOWED,               /*< nick=NotAllowed >*/
 	NM_DEVICE_ERROR_SPECIFIC_OBJECT_NOT_FOUND, /*< nick=SpecificObjectNotFound >*/
 	NM_DEVICE_ERROR_VERSION_ID_MISMATCH,       /*< nick=VersionIdMismatch >*/
+	NM_DEVICE_ERROR_MISSING_DEPENDENCIES,      /*< nick=MissingDependencies >*/
 } NMDeviceError;
 
 #define NM_DEVICE_ERROR nm_device_error_quark ()

src/devices/nm-device-infiniband.c

@@ -269,13 +269,13 @@ create_and_realize (NMDevice *device,
 	}
 
 	if (!parent) {
-		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_FAILED,
+		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_MISSING_DEPENDENCIES,
 		             "InfiniBand partitions can not be created without a parent interface");
 		return FALSE;
 	}
 
 	if (!NM_IS_DEVICE_INFINIBAND (parent)) {
-		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_FAILED,
+		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_MISSING_DEPENDENCIES,
 		             "Parent interface %s must be an InfiniBand interface",
 		             nm_device_get_iface (parent));
 		return FALSE;
@@ -283,7 +283,7 @@ create_and_realize (NMDevice *device,
 
 	priv->parent_ifindex = nm_device_get_ifindex (parent);
 	if (priv->parent_ifindex <= 0) {
-		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_FAILED,
+		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_MISSING_DEPENDENCIES,
 		             "failed to get InfiniBand parent %s ifindex",
 		             nm_device_get_iface (parent));
 		return FALSE;

src/devices/nm-device-macsec.c

@@ -692,7 +692,7 @@ create_and_realize (NMDevice *device,
 	g_assert (s_macsec);
 
 	if (!parent) {
-		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_FAILED,
+		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_MISSING_DEPENDENCIES,
 		             "MACsec devices can not be created without a parent interface");
 		return FALSE;
 	}

src/devices/nm-device-macvlan.c

@@ -234,7 +234,7 @@ create_and_realize (NMDevice *device,
 	parent_ifindex = parent ? nm_device_get_ifindex (parent) : 0;
 
 	if (parent_ifindex <= 0) {
-		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_FAILED,
+		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_MISSING_DEPENDENCIES,
 		             "MACVLAN devices can not be created without a parent interface");
 		g_return_val_if_fail (!parent, FALSE);
 		return FALSE;

src/devices/nm-device-ppp.c

@@ -209,7 +209,7 @@ create_and_realize (NMDevice *device,
 	int parent_ifindex;
 
 	if (!parent) {
-		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_FAILED,
+		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_MISSING_DEPENDENCIES,
 		             "PPP devices can not be created without a parent interface");
 		return FALSE;
 	}

src/devices/nm-device-vlan.c

@@ -231,14 +231,14 @@ create_and_realize (NMDevice *device,
 	g_assert (s_vlan);
 
 	if (!parent) {
-		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_FAILED,
+		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_MISSING_DEPENDENCIES,
 		             "VLAN devices can not be created without a parent interface");
 		return FALSE;
 	}
 
 	parent_ifindex = nm_device_get_ifindex (parent);
 	if (parent_ifindex <= 0) {
-		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_FAILED,
+		g_set_error (error, NM_DEVICE_ERROR, NM_DEVICE_ERROR_MISSING_DEPENDENCIES,
 		             "cannot retrieve ifindex of interface %s (%s): skip VLAN creation for now",
 		             nm_device_get_iface (parent),
 		             nm_device_get_type_desc (parent));

src/nm-manager.c

@@ -1301,6 +1301,7 @@ system_create_virtual_device (NMManager *self, NMConnection *connection)
 	gs_free char *iface = NULL;
 	NMDevice *device = NULL, *parent = NULL;
 	GError *error = NULL;
+	NMLogLevel log_level;
 
 	g_return_val_if_fail (NM_IS_MANAGER (self), NULL);
 	g_return_val_if_fail (NM_IS_CONNECTION (connection), NULL);
@@ -1381,8 +1382,14 @@ system_create_virtual_device (NMManager *self, NMConnection *connection)
 
 		/* Create any backing resources the device needs */
 		if (!nm_device_create_and_realize (device, connection, parent, &error)) {
-			_LOG3W (LOGD_DEVICE, connection, "couldn't create the device: %s",
+			log_level = g_error_matches (error,
-			        error->message);
+			                             NM_DEVICE_ERROR,
+			                             NM_DEVICE_ERROR_MISSING_DEPENDENCIES)
+			            ? LOGL_DEBUG
+			            : LOGL_ERR;
+			_NMLOG3 (log_level, LOGD_DEVICE, connection,
+			         "couldn't create the device: %s",
+			         error->message);
 			g_error_free (error);
 			remove_device (self, device, FALSE, TRUE);
 			return NULL;