team: add netpoll support

It's done in very similar way this is done in bonding and bridge.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/team/team.c

@@ -18,6 +18,7 @@
 #include <linux/ctype.h>
 #include <linux/notifier.h>
 #include <linux/netdevice.h>
+#include <linux/netpoll.h>
 #include <linux/if_vlan.h>
 #include <linux/if_arp.h>
 #include <linux/socket.h>
@@ -787,6 +788,58 @@ static void team_port_leave(struct team *team, struct team_port *port)
 	dev_put(team->dev);
 }
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static int team_port_enable_netpoll(struct team *team, struct team_port *port)
+{
+	struct netpoll *np;
+	int err;
+
+	np = kzalloc(sizeof(*np), GFP_KERNEL);
+	if (!np)
+		return -ENOMEM;
+
+	err = __netpoll_setup(np, port->dev);
+	if (err) {
+		kfree(np);
+		return err;
+	}
+	port->np = np;
+	return err;
+}
+
+static void team_port_disable_netpoll(struct team_port *port)
+{
+	struct netpoll *np = port->np;
+
+	if (!np)
+		return;
+	port->np = NULL;
+
+	/* Wait for transmitting packets to finish before freeing. */
+	synchronize_rcu_bh();
+	__netpoll_cleanup(np);
+	kfree(np);
+}
+
+static struct netpoll_info *team_netpoll_info(struct team *team)
+{
+	return team->dev->npinfo;
+}
+
+#else
+static int team_port_enable_netpoll(struct team *team, struct team_port *port)
+{
+	return 0;
+}
+static void team_port_disable_netpoll(struct team_port *port)
+{
+}
+static struct netpoll_info *team_netpoll_info(struct team *team)
+{
+	return NULL;
+}
+#endif
+
 static void __team_port_change_check(struct team_port *port, bool linkup);
 
 static int team_port_add(struct team *team, struct net_device *port_dev)
@@ -853,6 +906,15 @@ static int team_port_add(struct team *team, struct net_device *port_dev)
 		goto err_vids_add;
 	}
 
+	if (team_netpoll_info(team)) {
+		err = team_port_enable_netpoll(team, port);
+		if (err) {
+			netdev_err(dev, "Failed to enable netpoll on device %s\n",
+				   portname);
+			goto err_enable_netpoll;
+		}
+	}
+
 	err = netdev_set_master(port_dev, dev);
 	if (err) {
 		netdev_err(dev, "Device %s failed to set master\n", portname);
@@ -892,6 +954,9 @@ static int team_port_add(struct team *team, struct net_device *port_dev)
 	netdev_set_master(port_dev, NULL);
 
 err_set_master:
+	team_port_disable_netpoll(port);
+
+err_enable_netpoll:
 	vlan_vids_del_by_dev(port_dev, dev);
 
 err_vids_add:
@@ -932,6 +997,7 @@ static int team_port_del(struct team *team, struct net_device *port_dev)
 	list_del_rcu(&port->list);
 	netdev_rx_handler_unregister(port_dev);
 	netdev_set_master(port_dev, NULL);
+	team_port_disable_netpoll(port);
 	vlan_vids_del_by_dev(port_dev, dev);
 	dev_close(port_dev);
 	team_port_leave(team, port);
@@ -1307,6 +1373,48 @@ static int team_vlan_rx_kill_vid(struct net_device *dev, uint16_t vid)
 	return 0;
 }
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static void team_poll_controller(struct net_device *dev)
+{
+}
+
+static void __team_netpoll_cleanup(struct team *team)
+{
+	struct team_port *port;
+
+	list_for_each_entry(port, &team->port_list, list)
+		team_port_disable_netpoll(port);
+}
+
+static void team_netpoll_cleanup(struct net_device *dev)
+{
+	struct team *team = netdev_priv(dev);
+
+	mutex_lock(&team->lock);
+	__team_netpoll_cleanup(team);
+	mutex_unlock(&team->lock);
+}
+
+static int team_netpoll_setup(struct net_device *dev,
+			      struct netpoll_info *npifo)
+{
+	struct team *team = netdev_priv(dev);
+	struct team_port *port;
+	int err;
+
+	mutex_lock(&team->lock);
+	list_for_each_entry(port, &team->port_list, list) {
+		err = team_port_enable_netpoll(team, port);
+		if (err) {
+			__team_netpoll_cleanup(team);
+			break;
+		}
+	}
+	mutex_unlock(&team->lock);
+	return err;
+}
+#endif
+
 static int team_add_slave(struct net_device *dev, struct net_device *port_dev)
 {
 	struct team *team = netdev_priv(dev);
@@ -1363,6 +1471,11 @@ static const struct net_device_ops team_netdev_ops = {
 	.ndo_get_stats64	= team_get_stats64,
 	.ndo_vlan_rx_add_vid	= team_vlan_rx_add_vid,
 	.ndo_vlan_rx_kill_vid	= team_vlan_rx_kill_vid,
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	.ndo_poll_controller	= team_poll_controller,
+	.ndo_netpoll_setup	= team_netpoll_setup,
+	.ndo_netpoll_cleanup	= team_netpoll_cleanup,
+#endif
 	.ndo_add_slave		= team_add_slave,
 	.ndo_del_slave		= team_del_slave,
 	.ndo_fix_features	= team_fix_features,

drivers/net/team/team_mode_activebackup.c

@@ -43,8 +43,7 @@ static bool ab_transmit(struct team *team, struct sk_buff *skb)
 	active_port = rcu_dereference_bh(ab_priv(team)->active_port);
 	if (unlikely(!active_port))
 		goto drop;
-	skb->dev = active_port->dev;
-	if (dev_queue_xmit(skb))
+	if (team_dev_queue_xmit(team, active_port, skb))
 		return false;
 	return true;
 

drivers/net/team/team_mode_broadcast.c

@@ -29,8 +29,8 @@ static bool bc_transmit(struct team *team, struct sk_buff *skb)
 			if (last) {
 				skb2 = skb_clone(skb, GFP_ATOMIC);
 				if (skb2) {
-					skb2->dev = last->dev;
-					ret = dev_queue_xmit(skb2);
+					ret = team_dev_queue_xmit(team, last,
+								  skb2);
 					if (!sum_ret)
 						sum_ret = ret;
 				}
@@ -39,8 +39,7 @@ static bool bc_transmit(struct team *team, struct sk_buff *skb)
 		}
 	}
 	if (last) {
-		skb->dev = last->dev;
-		ret = dev_queue_xmit(skb);
+		ret = team_dev_queue_xmit(team, last, skb);
 		if (!sum_ret)
 			sum_ret = ret;
 	}

drivers/net/team/team_mode_loadbalance.c

@@ -217,8 +217,7 @@ static bool lb_transmit(struct team *team, struct sk_buff *skb)
 	port = select_tx_port_func(team, lb_priv, skb, hash);
 	if (unlikely(!port))
 		goto drop;
-	skb->dev = port->dev;
-	if (dev_queue_xmit(skb))
+	if (team_dev_queue_xmit(team, port, skb))
 		return false;
 	lb_update_tx_stats(tx_bytes, lb_priv, get_lb_port_priv(port), hash);
 	return true;

drivers/net/team/team_mode_roundrobin.c

@@ -55,8 +55,7 @@ static bool rr_transmit(struct team *team, struct sk_buff *skb)
 	port = __get_first_port_up(team, port);
 	if (unlikely(!port))
 		goto drop;
-	skb->dev = port->dev;
-	if (dev_queue_xmit(skb))
+	if (team_dev_queue_xmit(team, port, skb))
 		return false;
 	return true;
 

include/linux/if_team.h

@@ -13,6 +13,8 @@
 
 #ifdef __KERNEL__
 
+#include <linux/netpoll.h>
+
 struct team_pcpu_stats {
 	u64			rx_packets;
 	u64			rx_bytes;
@@ -60,6 +62,10 @@ struct team_port {
 		unsigned int mtu;
 	} orig;
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+	struct netpoll *np;
+#endif
+
 	long mode_priv[0];
 };
 
@@ -73,6 +79,33 @@ static inline bool team_port_txable(struct team_port *port)
 	return port->linkup && team_port_enabled(port);
 }
 
+#ifdef CONFIG_NET_POLL_CONTROLLER
+static inline void team_netpoll_send_skb(struct team_port *port,
+					 struct sk_buff *skb)
+{
+	struct netpoll *np = port->np;
+
+	if (np)
+		netpoll_send_skb(np, skb);
+}
+#else
+static inline void team_netpoll_send_skb(struct team_port *port,
+					 struct sk_buff *skb)
+{
+}
+#endif
+
+static inline int team_dev_queue_xmit(struct team *team, struct team_port *port,
+				      struct sk_buff *skb)
+{
+	skb->dev = port->dev;
+	if (unlikely(netpoll_tx_running(port->dev))) {
+		team_netpoll_send_skb(port, skb);
+		return 0;
+	}
+	return dev_queue_xmit(skb);
+}
+
 struct team_mode_ops {
 	int (*init)(struct team *team);
 	void (*exit)(struct team *team);