net: Add MDB bulk deletion device operation

Add MDB net device operation that will be invoked by rtnetlink code in
response to received 'RTM_DELMDB' messages with the 'NLM_F_BULK' flag
set. Subsequent patches will implement the operation in the bridge and
VXLAN drivers.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netdevice.h

@@ -1329,6 +1329,9 @@ struct netdev_net_notifier {
  * int (*ndo_mdb_del)(struct net_device *dev, struct nlattr *tb[],
  *		      struct netlink_ext_ack *extack);
  *	Deletes the MDB entry from dev.
+ * int (*ndo_mdb_del_bulk)(struct net_device *dev, struct nlattr *tb[],
+ *			   struct netlink_ext_ack *extack);
+ *	Bulk deletes MDB entries from dev.
  * int (*ndo_mdb_dump)(struct net_device *dev, struct sk_buff *skb,
  *		       struct netlink_callback *cb);
  *	Dumps MDB entries from dev. The first argument (marker) in the netlink
@@ -1611,6 +1614,9 @@ struct net_device_ops {
 	int			(*ndo_mdb_del)(struct net_device *dev,
 					       struct nlattr *tb[],
 					       struct netlink_ext_ack *extack);
+	int			(*ndo_mdb_del_bulk)(struct net_device *dev,
+						    struct nlattr *tb[],
+						    struct netlink_ext_ack *extack);
 	int			(*ndo_mdb_dump)(struct net_device *dev,
 						struct sk_buff *skb,
 						struct netlink_callback *cb);