net: conn_mgr_connectivity: idle timeouts

Implement idle timeouts, primarily in the common connectivity library,
with individual interfaces notifying the library when the interface has
been used.

Signed-off-by: Jordan Yates <[email protected]>

Author: JordanYates

include/zephyr/net/conn_mgr_connectivity.h

@@ -298,6 +298,19 @@ int conn_mgr_if_get_idle_timeout(struct net_if *iface);
  */
 int conn_mgr_if_set_idle_timeout(struct net_if *iface, int timeout);
 
+#if defined(CONFIG_NET_CONNECTION_MANAGER) || defined(__DOXYGEN__)
+/**
+ * @brief Notify connection manager that interface was just used
+ *
+ * @note Typically called from network drivers, not application software.
+ *
+ * @param iface iface that was just used
+ */
+void conn_mgr_if_used(struct net_if *iface);
+#else
+#define conn_mgr_if_used(iface) (void)(iface)
+#endif /* defined(CONFIG_NET_CONNECTION_MANAGER) || defined(__DOXYGEN__) */
+
 /**
  * @}
  */

include/zephyr/net/conn_mgr_connectivity_impl.h

@@ -206,6 +206,9 @@ struct conn_mgr_conn_binding {
 	/** @} */
 
 /** @cond INTERNAL_HIDDEN */
+	/* Internal-use work item for tracking interface idle timeouts */
+	struct k_work_delayable idle_worker;
+
 	/* Internal-use mutex for protecting access to the binding and API functions. */
 	struct k_mutex *mutex;
 /** @endcond */

subsys/net/conn_mgr/conn_mgr_connectivity.c

@@ -51,7 +51,7 @@ int conn_mgr_if_connect(struct net_if *iface)
 	return status;
 }
 
-int conn_mgr_if_disconnect(struct net_if *iface)
+static int conn_mgr_if_disconnect_internal(struct net_if *iface, bool idle_timeout)
 {
 	struct conn_mgr_conn_binding *binding;
 	struct conn_mgr_conn_api *api;
@@ -75,7 +75,9 @@ int conn_mgr_if_disconnect(struct net_if *iface)
 		goto out;
 	}
 
-	conn_mgr_if_set_flag(iface, CONN_MGR_IF_DISCONNECTING, true);
+	if (!idle_timeout) {
+		conn_mgr_if_set_flag(iface, CONN_MGR_IF_DISCONNECTING, true);
+	}
 
 	status = api->disconnect(binding);
 
@@ -85,6 +87,11 @@ int conn_mgr_if_disconnect(struct net_if *iface)
 	return status;
 }
 
+int conn_mgr_if_disconnect(struct net_if *iface)
+{
+	return conn_mgr_if_disconnect_internal(iface, false);
+}
+
 bool conn_mgr_if_is_bound(struct net_if *iface)
 {
 	struct conn_mgr_conn_binding *binding = conn_mgr_if_get_binding(iface);
@@ -261,6 +268,19 @@ int conn_mgr_if_set_idle_timeout(struct net_if *iface, int timeout)
 	return 0;
 }
 
+void conn_mgr_if_used(struct net_if *iface)
+{
+	struct conn_mgr_conn_binding *binding = conn_mgr_if_get_binding(iface);
+
+	if (binding == NULL) {
+		return;
+	}
+	if (binding->idle_timeout == CONN_MGR_IF_NO_TIMEOUT) {
+		return;
+	}
+	k_work_reschedule(&binding->idle_worker, K_SECONDS(binding->idle_timeout));
+}
+
 /* Automated behavior handling */
 
 /**
@@ -299,6 +319,8 @@ static void conn_mgr_conn_handle_iface_admin_up(struct net_if *iface)
  */
 static void conn_mgr_conn_if_auto_admin_down(struct net_if *iface)
 {
+	struct conn_mgr_conn_binding *binding = conn_mgr_if_get_binding(iface);
+
 	/* NOTE: This will be double-fired for ifaces that are both non-persistent
 	 * and are being directly requested to disconnect, since both of these conditions
 	 * separately trigger conn_mgr_conn_if_auto_admin_down.
@@ -308,17 +330,40 @@ static void conn_mgr_conn_if_auto_admin_down(struct net_if *iface)
 	 */
 
 	/* Ignore ifaces that don't have connectivity implementations */
-	if (!conn_mgr_if_is_bound(iface)) {
+	if (binding == NULL) {
 		return;
 	}
 
+	/* Cancel any pending idle timeouts */
+	k_work_cancel_delayable(&binding->idle_worker);
+
 	/* Take the iface admin-down if AUTO_DOWN is enabled */
 	if (IS_ENABLED(CONFIG_NET_CONNECTION_MANAGER_AUTO_IF_DOWN) &&
 	    !conn_mgr_if_get_flag(iface, CONN_MGR_IF_NO_AUTO_DOWN)) {
 		net_if_down(iface);
 	}
 }
 
+static void conn_mgr_conn_handle_iface_up(struct net_if *iface)
+{
+	struct conn_mgr_conn_binding *binding = conn_mgr_if_get_binding(iface);
+	int idle_timeout;
+
+	/* Ignore ifaces that don't have connectivity implementations */
+	if (binding == NULL) {
+		return;
+	}
+
+	idle_timeout = conn_mgr_if_get_idle_timeout(iface);
+	if (idle_timeout == CONN_MGR_IF_NO_TIMEOUT) {
+		/* No idle timeout configured for the interface */
+		return;
+	}
+
+	/* Start the idle timeout */
+	k_work_reschedule(&binding->idle_worker, K_SECONDS(idle_timeout));
+}
+
 /**
  * @brief Perform automated behaviors in response to any iface that loses oper-up state.
  *
@@ -358,6 +403,9 @@ static void conn_mgr_conn_iface_handler(struct net_mgmt_event_callback *cb, uint
 	}
 
 	switch (mgmt_event) {
+	case NET_EVENT_IF_UP:
+		conn_mgr_conn_handle_iface_up(iface);
+		break;
 	case NET_EVENT_IF_DOWN:
 		conn_mgr_conn_handle_iface_down(iface);
 		break;
@@ -393,8 +441,22 @@ static void conn_mgr_conn_self_handler(struct net_mgmt_event_callback *cb, uint6
 		 */
 		conn_mgr_conn_if_auto_admin_down(iface);
 		break;
+	case NET_EVENT_CONN_CMD_IF_IDLE_TIMEOUT:
+		/* Interface is idle, disconnect */
+		LOG_DBG("iface %d (%p) idle", net_if_get_by_iface(iface), iface);
+		conn_mgr_if_disconnect_internal(iface, true);
+		break;
 	}
+}
+
+static void conn_mgr_iface_idle_fn(struct k_work *work)
+{
+	struct k_work_delayable *dwork = k_work_delayable_from_work(work);
+	struct conn_mgr_conn_binding *binding =
+		CONTAINER_OF(dwork, struct conn_mgr_conn_binding, idle_worker);
 
+	LOG_DBG("iface %d (%p) idle", net_if_get_by_iface(binding->iface), binding->iface);
+	net_mgmt_event_notify(NET_EVENT_CONN_IF_IDLE_TIMEOUT, binding->iface);
 }
 
 void conn_mgr_conn_init(void)
@@ -407,6 +469,10 @@ void conn_mgr_conn_init(void)
 		} else if (binding->impl->api->init) {
 			conn_mgr_binding_lock(binding);
 
+			/* Initialise idle worker */
+
+			k_work_init_delayable(&binding->idle_worker, conn_mgr_iface_idle_fn);
+
 			/* Set initial default values for binding state */
 
 			binding->timeout = CONN_MGR_IF_NO_TIMEOUT;

subsys/net/conn_mgr/conn_mgr_private.h

@@ -40,10 +40,12 @@
 					 NET_EVENT_IF_UP)
 
 #define CONN_MGR_CONN_IFACE_EVENTS_MASK	(NET_EVENT_IF_ADMIN_UP		|\
+					 NET_EVENT_IF_UP		|\
 					 NET_EVENT_IF_DOWN)
 
 #define CONN_MGR_CONN_SELF_EVENTS_MASK	(NET_EVENT_CONN_IF_TIMEOUT	| \
-					 NET_EVENT_CONN_IF_FATAL_ERROR)
+					 NET_EVENT_CONN_IF_FATAL_ERROR	| \
+					 NET_EVENT_CONN_IF_IDLE_TIMEOUT)
 
 #define CONN_MGR_IPV6_EVENTS_MASK	(NET_EVENT_IPV6_ADDR_ADD	| \
 					 NET_EVENT_IPV6_ADDR_DEL	| \