nfp: register a notifier handler in a central location for the device

Code interested in networking events registers its own notifier
handlers.  Create one device-wide notifier instance.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/nfp_app.c

@@ -136,6 +136,53 @@ nfp_app_reprs_set(struct nfp_app *app, enum nfp_repr_type type,
 	return old;
 }
 
+static int
+nfp_app_netdev_event(struct notifier_block *nb, unsigned long event, void *ptr)
+{
+	struct net_device *netdev;
+	struct nfp_app *app;
+
+	netdev = netdev_notifier_info_to_dev(ptr);
+	app = container_of(nb, struct nfp_app, netdev_nb);
+
+	if (app->type->netdev_event)
+		return app->type->netdev_event(app, netdev, event, ptr);
+	return NOTIFY_DONE;
+}
+
+int nfp_app_start(struct nfp_app *app, struct nfp_net *ctrl)
+{
+	int err;
+
+	app->ctrl = ctrl;
+
+	if (app->type->start) {
+		err = app->type->start(app);
+		if (err)
+			return err;
+	}
+
+	app->netdev_nb.notifier_call = nfp_app_netdev_event;
+	err = register_netdevice_notifier(&app->netdev_nb);
+	if (err)
+		goto err_app_stop;
+
+	return 0;
+
+err_app_stop:
+	if (app->type->stop)
+		app->type->stop(app);
+	return err;
+}
+
+void nfp_app_stop(struct nfp_app *app)
+{
+	unregister_netdevice_notifier(&app->netdev_nb);
+
+	if (app->type->stop)
+		app->type->stop(app);
+}
+
 struct nfp_app *nfp_app_alloc(struct nfp_pf *pf, enum nfp_app_id id)
 {
 	struct nfp_app *app;

drivers/net/ethernet/netronome/nfp/nfp_app.h

@@ -69,6 +69,7 @@ extern const struct nfp_app_type app_abm;
  * @port_get_stats_strings:	get strings for extra statistics
  * @start:	start application logic
  * @stop:	stop application logic
+ * @netdev_event:	Netdevice notifier event
  * @ctrl_msg_rx:    control message handler
  * @ctrl_msg_rx_raw:	handler for control messages from data queues
  * @setup_tc:	setup TC ndo
@@ -122,6 +123,9 @@ struct nfp_app_type {
 	int (*start)(struct nfp_app *app);
 	void (*stop)(struct nfp_app *app);
 
+	int (*netdev_event)(struct nfp_app *app, struct net_device *netdev,
+			    unsigned long event, void *ptr);
+
 	void (*ctrl_msg_rx)(struct nfp_app *app, struct sk_buff *skb);
 	void (*ctrl_msg_rx_raw)(struct nfp_app *app, const void *data,
 				unsigned int len);
@@ -151,6 +155,7 @@ struct nfp_app_type {
  * @reprs:	array of pointers to representors
  * @type:	pointer to const application ops and info
  * @ctrl_mtu:	MTU to set on the control vNIC (set in .init())
+ * @netdev_nb:	Netdevice notifier block
  * @priv:	app-specific priv data
  */
 struct nfp_app {
@@ -163,6 +168,9 @@ struct nfp_app {
 
 	const struct nfp_app_type *type;
 	unsigned int ctrl_mtu;
+
+	struct notifier_block netdev_nb;
+
 	void *priv;
 };
 
@@ -264,21 +272,6 @@ nfp_app_repr_change_mtu(struct nfp_app *app, struct net_device *netdev,
 	return app->type->repr_change_mtu(app, netdev, new_mtu);
 }
 
-static inline int nfp_app_start(struct nfp_app *app, struct nfp_net *ctrl)
-{
-	app->ctrl = ctrl;
-	if (!app->type->start)
-		return 0;
-	return app->type->start(app);
-}
-
-static inline void nfp_app_stop(struct nfp_app *app)
-{
-	if (!app->type->stop)
-		return;
-	app->type->stop(app);
-}
-
 static inline const char *nfp_app_name(struct nfp_app *app)
 {
 	if (!app)
@@ -430,6 +423,8 @@ nfp_app_ctrl_msg_alloc(struct nfp_app *app, unsigned int size, gfp_t priority);
 
 struct nfp_app *nfp_app_alloc(struct nfp_pf *pf, enum nfp_app_id id);
 void nfp_app_free(struct nfp_app *app);
+int nfp_app_start(struct nfp_app *app, struct nfp_net *ctrl);
+void nfp_app_stop(struct nfp_app *app);
 
 /* Callbacks shared between apps */