openvswitch: add net device refcount tracker to struct vport

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net/openvswitch/vport-netdev.c

@@ -82,7 +82,7 @@ struct vport *ovs_netdev_link(struct vport *vport, const char *name)
 		err = -ENODEV;
 		goto error_free_vport;
 	}
-
+	netdev_tracker_alloc(vport->dev, &vport->dev_tracker, GFP_KERNEL);
 	if (vport->dev->flags & IFF_LOOPBACK ||
 	    (vport->dev->type != ARPHRD_ETHER &&
 	     vport->dev->type != ARPHRD_NONE) ||
@@ -115,7 +115,7 @@ struct vport *ovs_netdev_link(struct vport *vport, const char *name)
 error_unlock:
 	rtnl_unlock();
 error_put:
-	dev_put(vport->dev);
+	dev_put_track(vport->dev, &vport->dev_tracker);
 error_free_vport:
 	ovs_vport_free(vport);
 	return ERR_PTR(err);
@@ -137,7 +137,7 @@ static void vport_netdev_free(struct rcu_head *rcu)
 {
 	struct vport *vport = container_of(rcu, struct vport, rcu);
 
-	dev_put(vport->dev);
+	dev_put_track(vport->dev, &vport->dev_tracker);
 	ovs_vport_free(vport);
 }
 
@@ -173,7 +173,7 @@ void ovs_netdev_tunnel_destroy(struct vport *vport)
 	 */
 	if (vport->dev->reg_state == NETREG_REGISTERED)
 		rtnl_delete_link(vport->dev);
-	dev_put(vport->dev);
+	dev_put_track(vport->dev, &vport->dev_tracker);
 	vport->dev = NULL;
 	rtnl_unlock();
 

net/openvswitch/vport.h

@@ -58,6 +58,7 @@ struct vport_portids {
 /**
  * struct vport - one port within a datapath
  * @dev: Pointer to net_device.
+ * @dev_tracker: refcount tracker for @dev reference
  * @dp: Datapath to which this port belongs.
  * @upcall_portids: RCU protected 'struct vport_portids'.
  * @port_no: Index into @dp's @ports array.
@@ -69,6 +70,7 @@ struct vport_portids {
  */
 struct vport {
 	struct net_device *dev;
+	netdevice_tracker dev_tracker;
 	struct datapath	*dp;
 	struct vport_portids __rcu *upcall_portids;
 	u16 port_no;