net: add netif_is_team_master helper

BugLink: http://bugs.launchpad.net/bugs/1562310

Similar to other helpers, caller can use this to find out if device is
team master.
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit c981e421)
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>

drivers/net/team/team.c

@@ -2054,6 +2054,7 @@ static void team_setup(struct net_device *dev)
 	dev->flags |= IFF_MULTICAST;
 	dev->priv_flags &= ~(IFF_XMIT_DST_RELEASE | IFF_TX_SKB_SHARING);
 	dev->priv_flags |= IFF_NO_QUEUE;
+	dev->priv_flags |= IFF_TEAM;
 
 	/*
 	 * Indicate we support unicast address filtering. That way core won't

include/linux/netdevice.h

@@ -1289,6 +1289,7 @@ struct net_device_ops {
  * @IFF_NO_QUEUE: device can run without qdisc attached
  * @IFF_OPENVSWITCH: device is a Open vSwitch master
  * @IFF_L3MDEV_SLAVE: device is enslaved to an L3 master device
+ * @IFF_TEAM: device is a team device
  */
 enum netdev_priv_flags {
 	IFF_802_1Q_VLAN			= 1<<0,
@@ -1315,6 +1316,7 @@ enum netdev_priv_flags {
 	IFF_NO_QUEUE			= 1<<21,
 	IFF_OPENVSWITCH			= 1<<22,
 	IFF_L3MDEV_SLAVE		= 1<<23,
+	IFF_TEAM			= 1<<24,
 };
 
 #define IFF_802_1Q_VLAN			IFF_802_1Q_VLAN
@@ -1341,6 +1343,7 @@ enum netdev_priv_flags {
 #define IFF_NO_QUEUE			IFF_NO_QUEUE
 #define IFF_OPENVSWITCH			IFF_OPENVSWITCH
 #define IFF_L3MDEV_SLAVE		IFF_L3MDEV_SLAVE
+#define IFF_TEAM			IFF_TEAM
 
 /**
  *	struct net_device - The DEVICE structure.
@@ -3886,6 +3889,11 @@ static inline bool netif_is_ovs_master(const struct net_device *dev)
 	return dev->priv_flags & IFF_OPENVSWITCH;
 }
 
+static inline bool netif_is_team_master(struct net_device *dev)
+{
+	return dev->priv_flags & IFF_TEAM;
+}
+
 /* This device needs to keep skb dst for qdisc enqueue or ndo_start_xmit() */
 static inline void netif_keep_dst(struct net_device *dev)
 {