net/hsr: Use list_head (and rcu) instead of array for slave devices.

Signed-off-by: Arvid Brodin <arvid.brodin@alten.se>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/hsr/hsr_framereg.h

@@ -18,18 +18,16 @@ struct hsr_node;
 
 struct hsr_node *hsr_find_node(struct list_head *node_db, struct sk_buff *skb);
 
-struct hsr_node *hsr_merge_node(struct hsr_priv *hsr,
-				struct hsr_node *node,
-				struct sk_buff *skb,
-				enum hsr_dev_idx dev_idx);
+struct hsr_node *hsr_merge_node(struct hsr_node *node, struct sk_buff *skb,
+				struct hsr_port *port);
 
 void hsr_addr_subst_source(struct hsr_priv *hsr, struct sk_buff *skb);
 void hsr_addr_subst_dest(struct hsr_priv *hsr, struct ethhdr *ethhdr,
-			 enum hsr_dev_idx dev_idx);
+			 struct hsr_port *port);
 
-void hsr_register_frame_in(struct hsr_node *node, enum hsr_dev_idx dev_idx);
+void hsr_register_frame_in(struct hsr_node *node, struct hsr_port *port);
 
-int hsr_register_frame_out(struct hsr_node *node, enum hsr_dev_idx dev_idx,
+int hsr_register_frame_out(struct hsr_node *node, struct hsr_port *port,
 			   struct sk_buff *skb);
 
 void hsr_prune_nodes(unsigned long data);

net/hsr/hsr_main.c

@@ -39,76 +39,25 @@ void unregister_hsr_master(struct hsr_priv *hsr)
 		}
 }
 
-bool is_hsr_slave(struct net_device *dev)
-{
-	struct hsr_priv *hsr_it;
-
-	list_for_each_entry_rcu(hsr_it, &hsr_list, hsr_list) {
-		if (dev == hsr_it->slave[0])
-			return true;
-		if (dev == hsr_it->slave[1])
-			return true;
-	}
-
-	return false;
-}
-
-/* If dev is a HSR slave device, return the virtual master device. Return NULL
- * otherwise.
- */
-struct hsr_priv *get_hsr_master(struct net_device *dev)
-{
-	struct hsr_priv *hsr;
-
-	rcu_read_lock();
-	list_for_each_entry_rcu(hsr, &hsr_list, hsr_list)
-		if ((dev == hsr->slave[0]) ||
-		    (dev == hsr->slave[1])) {
-			rcu_read_unlock();
-			return hsr;
-		}
-
-	rcu_read_unlock();
-	return NULL;
-}
-
-/* If dev is a HSR slave device, return the other slave device. Return NULL
- * otherwise.
- */
-struct net_device *get_other_slave(struct hsr_priv *hsr,
-				   struct net_device *dev)
-{
-	if (dev == hsr->slave[0])
-		return hsr->slave[1];
-	if (dev == hsr->slave[1])
-		return hsr->slave[0];
-
-	return NULL;
-}
-
 
 static int hsr_netdev_notify(struct notifier_block *nb, unsigned long event,
 			     void *ptr)
 {
-	struct net_device *slave, *other_slave;
+	struct net_device *dev;
+	struct hsr_port *port, *master;
 	struct hsr_priv *hsr;
 	int mtu_max;
 	int res;
-	struct net_device *dev;
 
 	dev = netdev_notifier_info_to_dev(ptr);
-
-	hsr = get_hsr_master(dev);
-	if (hsr) {
-		/* dev is a slave device */
-		slave = dev;
-		other_slave = get_other_slave(hsr, slave);
-	} else {
+	port = hsr_port_get_rtnl(dev);
+	if (port == NULL) {
 		if (!is_hsr_master(dev))
-			return NOTIFY_DONE;
+			return NOTIFY_DONE;	/* Not an HSR device */
 		hsr = netdev_priv(dev);
-		slave = hsr->slave[0];
-		other_slave = hsr->slave[1];
+		port = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+	} else {
+		hsr = port->hsr;
 	}
 
 	switch (event) {
@@ -118,48 +67,41 @@ static int hsr_netdev_notify(struct notifier_block *nb, unsigned long event,
 		hsr_check_carrier_and_operstate(hsr);
 		break;
 	case NETDEV_CHANGEADDR:
-
-		/* This should not happen since there's no ndo_set_mac_address()
-		 * for HSR devices - i.e. not supported.
-		 */
-		if (dev == hsr->dev)
+		if (port->type == HSR_PT_MASTER) {
+			/* This should not happen since there's no
+			 * ndo_set_mac_address() for HSR devices - i.e. not
+			 * supported.
+			 */
 			break;
+		}
 
-		if (dev == hsr->slave[0]) {
-			ether_addr_copy(hsr->dev->dev_addr, dev->dev_addr);
-			call_netdevice_notifiers(NETDEV_CHANGEADDR, hsr->dev);
+		master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+
+		if (port->type == HSR_PT_SLAVE_A) {
+			ether_addr_copy(master->dev->dev_addr, dev->dev_addr);
+			call_netdevice_notifiers(NETDEV_CHANGEADDR, master->dev);
 		}
 
 		/* Make sure we recognize frames from ourselves in hsr_rcv() */
-		other_slave = hsr->slave[1];
+		port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
 		res = hsr_create_self_node(&hsr->self_node_db,
-					   hsr->dev->dev_addr,
-					   other_slave ?
-						other_slave->dev_addr :
-						hsr->dev->dev_addr);
+					   master->dev->dev_addr,
+					   port ?
+						port->dev->dev_addr :
+						master->dev->dev_addr);
 		if (res)
-			netdev_warn(hsr->dev,
+			netdev_warn(master->dev,
 				    "Could not update HSR node address.\n");
 		break;
 	case NETDEV_CHANGEMTU:
-		if (dev == hsr->dev)
+		if (port->type == HSR_PT_MASTER)
 			break; /* Handled in ndo_change_mtu() */
-		mtu_max = hsr_get_max_mtu(hsr);
-		if (hsr->dev->mtu > mtu_max)
-			dev_set_mtu(hsr->dev, mtu_max);
+		mtu_max = hsr_get_max_mtu(port->hsr);
+		master = hsr_port_get_hsr(port->hsr, HSR_PT_MASTER);
+		master->dev->mtu = mtu_max;
 		break;
 	case NETDEV_UNREGISTER:
-		if (dev == hsr->slave[0]) {
-			hsr->slave[0] = NULL;
-			hsr_del_slave(hsr, 0);
-		}
-		if (dev == hsr->slave[1]) {
-			hsr->slave[1] = NULL;
-			hsr_del_slave(hsr, 1);
-		}
-
-		/* There should really be a way to set a new slave device... */
-
+		hsr_del_port(port);
 		break;
 	case NETDEV_PRE_TYPE_CHANGE:
 		/* HSR works only on Ethernet devices. Refuse slave to change
@@ -172,6 +114,16 @@ static int hsr_netdev_notify(struct notifier_block *nb, unsigned long event,
 }
 
 
+struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt)
+{
+	struct hsr_port *port;
+
+	hsr_for_each_port(hsr, port)
+		if (port->type == pt)
+			return port;
+	return NULL;
+}
+
 static struct notifier_block hsr_nb = {
 	.notifier_call = hsr_netdev_notify,	/* Slave event notifications */
 };

net/hsr/hsr_main.h

@@ -136,20 +136,26 @@ struct hsr_ethhdr_sp {
 } __packed;
 
 
-enum hsr_dev_idx {
-	HSR_DEV_NONE = -1,
-	HSR_DEV_SLAVE_A = 0,
-	HSR_DEV_SLAVE_B,
-	HSR_DEV_MASTER,
+enum hsr_port_type {
+	HSR_PT_NONE = 0,	/* Must be 0, used by framereg */
+	HSR_PT_SLAVE_A,
+	HSR_PT_SLAVE_B,
+	HSR_PT_INTERLINK,
+	HSR_PT_MASTER,
+	HSR_PT_PORTS,	/* This must be the last item in the enum */
+};
+
+struct hsr_port {
+	struct list_head	port_list;
+	struct net_device	*dev;
+	struct hsr_priv		*hsr;
+	enum hsr_port_type	type;
 };
-#define HSR_MAX_SLAVE	(HSR_DEV_SLAVE_B + 1)
-#define HSR_MAX_DEV	(HSR_DEV_MASTER + 1)
 
 struct hsr_priv {
 	struct list_head	hsr_list;	/* List of hsr devices */
 	struct rcu_head		rcu_head;
-	struct net_device	*dev;
-	struct net_device	*slave[HSR_MAX_SLAVE];
+	struct list_head	ports;
 	struct list_head	node_db;	/* Other HSR nodes */
 	struct list_head	self_node_db;	/* MACs of slaves */
 	struct timer_list	announce_timer;	/* Supervision frame dispatch */
@@ -160,11 +166,6 @@ struct hsr_priv {
 	unsigned char		sup_multicast_addr[ETH_ALEN];
 };
 
-void register_hsr_master(struct hsr_priv *hsr);
-void unregister_hsr_master(struct hsr_priv *hsr);
-bool is_hsr_slave(struct net_device *dev);
-struct hsr_priv *get_hsr_master(struct net_device *dev);
-struct net_device *get_other_slave(struct hsr_priv *hsr,
-				   struct net_device *dev);
+struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt);
 
 #endif /*  __HSR_PRIVATE_H */

net/hsr/hsr_netlink.c

@@ -64,7 +64,7 @@ static int hsr_newlink(struct net *src_net, struct net_device *dev,
 static int hsr_fill_info(struct sk_buff *skb, const struct net_device *dev)
 {
 	struct hsr_priv *hsr;
-	struct net_device *slave;
+	struct hsr_port *port;
 	int res;
 
 	hsr = netdev_priv(dev);
@@ -72,17 +72,17 @@ static int hsr_fill_info(struct sk_buff *skb, const struct net_device *dev)
 	res = 0;
 
 	rcu_read_lock();
-	slave = hsr->slave[0];
-	if (slave)
-		res = nla_put_u32(skb, IFLA_HSR_SLAVE1, slave->ifindex);
+	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
+	if (port)
+		res = nla_put_u32(skb, IFLA_HSR_SLAVE1, port->dev->ifindex);
 	rcu_read_unlock();
 	if (res)
 		goto nla_put_failure;
 
 	rcu_read_lock();
-	slave = hsr->slave[1];
-	if (slave)
-		res = nla_put_u32(skb, IFLA_HSR_SLAVE2, slave->ifindex);
+	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
+	if (port)
+		res = nla_put_u32(skb, IFLA_HSR_SLAVE2, port->dev->ifindex);
 	rcu_read_unlock();
 	if (res)
 		goto nla_put_failure;
@@ -141,13 +141,12 @@ static const struct genl_multicast_group hsr_mcgrps[] = {
  * (i.e. a link has failed somewhere).
  */
 void hsr_nl_ringerror(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN],
-		      enum hsr_dev_idx dev_idx)
+		      struct hsr_port *port)
 {
 	struct sk_buff *skb;
-	struct net_device *slave;
 	void *msg_head;
+	struct hsr_port *master;
 	int res;
-	int ifindex;
 
 	skb = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
 	if (!skb)
@@ -161,15 +160,7 @@ void hsr_nl_ringerror(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN],
 	if (res < 0)
 		goto nla_put_failure;
 
-	rcu_read_lock();
-	slave = hsr->slave[dev_idx];
-	if (slave)
-		ifindex = slave->ifindex;
-	else
-		ifindex = -1;
-	rcu_read_unlock();
-
-	res = nla_put_u32(skb, HSR_A_IFINDEX, ifindex);
+	res = nla_put_u32(skb, HSR_A_IFINDEX, port->dev->ifindex);
 	if (res < 0)
 		goto nla_put_failure;
 
@@ -182,7 +173,10 @@ void hsr_nl_ringerror(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN],
 	kfree_skb(skb);
 
 fail:
-	netdev_warn(hsr->dev, "Could not send HSR ring error message\n");
+	rcu_read_lock();
+	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+	netdev_warn(master->dev, "Could not send HSR ring error message\n");
+	rcu_read_unlock();
 }
 
 /* This is called when we haven't heard from the node with MAC address addr for
@@ -192,6 +186,7 @@ void hsr_nl_nodedown(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN])
 {
 	struct sk_buff *skb;
 	void *msg_head;
+	struct hsr_port *master;
 	int res;
 
 	skb = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
@@ -216,7 +211,10 @@ void hsr_nl_nodedown(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN])
 	kfree_skb(skb);
 
 fail:
-	netdev_warn(hsr->dev, "Could not send HSR node down\n");
+	rcu_read_lock();
+	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+	netdev_warn(master->dev, "Could not send HSR node down\n");
+	rcu_read_unlock();
 }
 
 
@@ -232,12 +230,13 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
 {
 	/* For receiving */
 	struct nlattr *na;
-	struct net_device *hsr_dev, *slave;
+	struct net_device *hsr_dev;
 
 	/* For sending */
 	struct sk_buff *skb_out;
 	void *msg_head;
 	struct hsr_priv *hsr;
+	struct hsr_port *port;
 	unsigned char hsr_node_addr_b[ETH_ALEN];
 	int hsr_node_if1_age;
 	u16 hsr_node_if1_seq;
@@ -319,9 +318,10 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
 	if (res < 0)
 		goto nla_put_failure;
 	rcu_read_lock();
-	slave = hsr->slave[0];
-	if (slave)
-		res = nla_put_u32(skb_out, HSR_A_IF1_IFINDEX, slave->ifindex);
+	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
+	if (port)
+		res = nla_put_u32(skb_out, HSR_A_IF1_IFINDEX,
+				  port->dev->ifindex);
 	rcu_read_unlock();
 	if (res < 0)
 		goto nla_put_failure;
@@ -333,9 +333,10 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
 	if (res < 0)
 		goto nla_put_failure;
 	rcu_read_lock();
-	slave = hsr->slave[1];
-	if (slave)
-		res = nla_put_u32(skb_out, HSR_A_IF2_IFINDEX, slave->ifindex);
+	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
+	if (port)
+		res = nla_put_u32(skb_out, HSR_A_IF2_IFINDEX,
+				  port->dev->ifindex);
 	rcu_read_unlock();
 	if (res < 0)
 		goto nla_put_failure;

net/hsr/hsr_netlink.h

@@ -17,12 +17,13 @@
 #include <uapi/linux/hsr_netlink.h>
 
 struct hsr_priv;
+struct hsr_port;
 
 int __init hsr_netlink_init(void);
 void __exit hsr_netlink_exit(void);
 
 void hsr_nl_ringerror(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN],
-		      int dev_idx);
+		      struct hsr_port *port);
 void hsr_nl_nodedown(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN]);
 void hsr_nl_framedrop(int dropcount, int dev_idx);
 void hsr_nl_linkdown(int dev_idx);

net/hsr/hsr_slave.c

@@ -17,7 +17,7 @@
 #include "hsr_framereg.h"
 
 
-static int check_slave_ok(struct net_device *dev)
+static int hsr_check_dev_ok(struct net_device *dev)
 {
 	/* Don't allow HSR on non-ethernet like devices */
 	if ((dev->flags & IFF_LOOPBACK) || (dev->type != ARPHRD_ETHER) ||
@@ -32,7 +32,7 @@ static int check_slave_ok(struct net_device *dev)
 		return -EINVAL;
 	}
 
-	if (is_hsr_slave(dev)) {
+	if (hsr_port_exists(dev)) {
 		netdev_info(dev, "This device is already a HSR slave.\n");
 		return -EINVAL;
 	}
@@ -116,38 +116,29 @@ static bool is_supervision_frame(struct hsr_priv *hsr, struct sk_buff *skb)
 rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
 {
 	struct sk_buff *skb = *pskb;
-	struct net_device *dev = skb->dev;
+	struct hsr_port *port, *other_port, *master;
 	struct hsr_priv *hsr;
-	struct net_device *other_slave;
 	struct hsr_node *node;
 	bool deliver_to_self;
 	struct sk_buff *skb_deliver;
-	enum hsr_dev_idx dev_in_idx, dev_other_idx;
 	bool dup_out;
 	int ret;
 
 	if (eth_hdr(skb)->h_proto != htons(ETH_P_PRP))
 		return RX_HANDLER_PASS;
 
-	hsr = get_hsr_master(dev);
-	if (!hsr) {
-		WARN_ON_ONCE(1);
-		return RX_HANDLER_PASS;
-	}
+	rcu_read_lock(); /* ports & node */
 
-	if (dev == hsr->slave[0]) {
-		dev_in_idx = HSR_DEV_SLAVE_A;
-		dev_other_idx = HSR_DEV_SLAVE_B;
-	} else {
-		dev_in_idx = HSR_DEV_SLAVE_B;
-		dev_other_idx = HSR_DEV_SLAVE_A;
-	}
+	port = hsr_port_get_rcu(skb->dev);
+	hsr = port->hsr;
+	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
 
 	node = hsr_find_node(&hsr->self_node_db, skb);
 	if (node) {
 		/* Always kill frames sent by ourselves */
 		kfree_skb(skb);
-		return RX_HANDLER_CONSUMED;
+		ret = RX_HANDLER_CONSUMED;
+		goto finish;
 	}
 
 	/* Is this frame a candidate for local reception? */
@@ -156,23 +147,22 @@ rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
 	    (skb->pkt_type == PACKET_MULTICAST) ||
 	    (skb->pkt_type == PACKET_BROADCAST))
 		deliver_to_self = true;
-	else if (ether_addr_equal(eth_hdr(skb)->h_dest, hsr->dev->dev_addr)) {
+	else if (ether_addr_equal(eth_hdr(skb)->h_dest,
+				  master->dev->dev_addr)) {
 		skb->pkt_type = PACKET_HOST;
 		deliver_to_self = true;
 	}
 
-
-	rcu_read_lock(); /* node_db */
 	node = hsr_find_node(&hsr->node_db, skb);
 
 	if (is_supervision_frame(hsr, skb)) {
 		skb_pull(skb, sizeof(struct hsr_sup_tag));
-		node = hsr_merge_node(hsr, node, skb, dev_in_idx);
+		node = hsr_merge_node(node, skb, port);
 		if (!node) {
-			rcu_read_unlock(); /* node_db */
 			kfree_skb(skb);
-			hsr->dev->stats.rx_dropped++;
-			return RX_HANDLER_CONSUMED;
+			master->dev->stats.rx_dropped++;
+			ret = RX_HANDLER_CONSUMED;
+			goto finish;
 		}
 		skb_push(skb, sizeof(struct hsr_sup_tag));
 		deliver_to_self = false;
@@ -182,46 +172,51 @@ rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
 		/* Source node unknown; this might be a HSR frame from
 		 * another net (different multicast address). Ignore it.
 		 */
-		rcu_read_unlock(); /* node_db */
 		kfree_skb(skb);
-		return RX_HANDLER_CONSUMED;
+		ret = RX_HANDLER_CONSUMED;
+		goto finish;
 	}
 
+	if (port->type == HSR_PT_SLAVE_A)
+		other_port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
+	else
+		other_port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
+
 	/* Register ALL incoming frames as outgoing through the other interface.
 	 * This allows us to register frames as incoming only if they are valid
 	 * for the receiving interface, without using a specific counter for
 	 * incoming frames.
 	 */
-	dup_out = hsr_register_frame_out(node, dev_other_idx, skb);
+	if (other_port)
+		dup_out = hsr_register_frame_out(node, other_port, skb);
+	else
+		dup_out = 0;
 	if (!dup_out)
-		hsr_register_frame_in(node, dev_in_idx);
+		hsr_register_frame_in(node, port);
 
 	/* Forward this frame? */
-	if (!dup_out && (skb->pkt_type != PACKET_HOST))
-		other_slave = get_other_slave(hsr, dev);
-	else
-		other_slave = NULL;
+	if (dup_out || (skb->pkt_type == PACKET_HOST))
+		other_port = NULL;
 
-	if (hsr_register_frame_out(node, HSR_DEV_MASTER, skb))
+	if (hsr_register_frame_out(node, master, skb))
 		deliver_to_self = false;
 
-	rcu_read_unlock(); /* node_db */
-
-	if (!deliver_to_self && !other_slave) {
+	if (!deliver_to_self && !other_port) {
 		kfree_skb(skb);
 		/* Circulated frame; silently remove it. */
-		return RX_HANDLER_CONSUMED;
+		ret = RX_HANDLER_CONSUMED;
+		goto finish;
 	}
 
 	skb_deliver = skb;
-	if (deliver_to_self && other_slave) {
+	if (deliver_to_self && other_port) {
 		/* skb_clone() is not enough since we will strip the hsr tag
 		 * and do address substitution below
 		 */
 		skb_deliver = pskb_copy(skb, GFP_ATOMIC);
 		if (!skb_deliver) {
 			deliver_to_self = false;
-			hsr->dev->stats.rx_dropped++;
+			master->dev->stats.rx_dropped++;
 		}
 	}
 
@@ -230,7 +225,7 @@ rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
 
 		skb_deliver = hsr_pull_tag(skb_deliver);
 		if (!skb_deliver) {
-			hsr->dev->stats.rx_dropped++;
+			master->dev->stats.rx_dropped++;
 			goto forward;
 		}
 #if !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
@@ -253,82 +248,130 @@ rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
 		skb_deliver->data -= HSR_HLEN;
 		skb_deliver->tail -= HSR_HLEN;
 #endif
-		skb_deliver->dev = hsr->dev;
+		skb_deliver->dev = master->dev;
 		hsr_addr_subst_source(hsr, skb_deliver);
 		multicast_frame = (skb_deliver->pkt_type == PACKET_MULTICAST);
 		ret = netif_rx(skb_deliver);
 		if (ret == NET_RX_DROP) {
-			hsr->dev->stats.rx_dropped++;
+			master->dev->stats.rx_dropped++;
 		} else {
-			hsr->dev->stats.rx_packets++;
-			hsr->dev->stats.rx_bytes += skb->len;
+			master->dev->stats.rx_packets++;
+			master->dev->stats.rx_bytes += skb->len;
 			if (multicast_frame)
-				hsr->dev->stats.multicast++;
+				master->dev->stats.multicast++;
 		}
 	}
 
 forward:
-	if (other_slave) {
+	if (other_port) {
 		skb_push(skb, ETH_HLEN);
-		skb->dev = other_slave;
+		skb->dev = other_port->dev;
 		dev_queue_xmit(skb);
 	}
 
-	return RX_HANDLER_CONSUMED;
+	ret = RX_HANDLER_CONSUMED;
+
+finish:
+	rcu_read_unlock();
+	return ret;
 }
 
-int hsr_add_slave(struct hsr_priv *hsr, struct net_device *dev, int idx)
+/* Setup device to be added to the HSR bridge. */
+static int hsr_portdev_setup(struct net_device *dev, struct hsr_port *port)
 {
 	int res;
 
 	dev_hold(dev);
-
-	res = check_slave_ok(dev);
-	if (res)
-		goto fail;
-
 	res = dev_set_promiscuity(dev, 1);
 	if (res)
-		goto fail;
-
-	res = netdev_rx_handler_register(dev, hsr_handle_frame, hsr);
+		goto fail_promiscuity;
+	res = netdev_rx_handler_register(dev, hsr_handle_frame, port);
 	if (res)
 		goto fail_rx_handler;
+	dev_disable_lro(dev);
 
-
-	hsr->slave[idx] = dev;
-
-	/* Set required header length */
-	if (dev->hard_header_len + HSR_HLEN > hsr->dev->hard_header_len)
-		hsr->dev->hard_header_len = dev->hard_header_len + HSR_HLEN;
-
-	dev_set_mtu(hsr->dev, hsr_get_max_mtu(hsr));
+	/* FIXME:
+	 * What does net device "adjacency" mean? Should we do
+	 * res = netdev_master_upper_dev_link(port->dev, port->hsr->dev); ?
+	 */
 
 	return 0;
 
 fail_rx_handler:
 	dev_set_promiscuity(dev, -1);
-
-fail:
+fail_promiscuity:
 	dev_put(dev);
+
 	return res;
 }
 
-void hsr_del_slave(struct hsr_priv *hsr, int idx)
+int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev,
+		 enum hsr_port_type type)
 {
-	struct net_device *slave;
+	struct hsr_port *port, *master;
+	int res;
 
-	slave = hsr->slave[idx];
-	hsr->slave[idx] = NULL;
+	if (type != HSR_PT_MASTER) {
+		res = hsr_check_dev_ok(dev);
+		if (res)
+			return res;
+	}
+
+	port = hsr_port_get_hsr(hsr, type);
+	if (port != NULL)
+		return -EBUSY;	/* This port already exists */
+
+	port = kzalloc(sizeof(*port), GFP_KERNEL);
+	if (port == NULL)
+		return -ENOMEM;
+
+	if (type != HSR_PT_MASTER) {
+		res = hsr_portdev_setup(dev, port);
+		if (res)
+			goto fail_dev_setup;
+	}
+
+	port->hsr = hsr;
+	port->dev = dev;
+	port->type = type;
+
+	list_add_tail_rcu(&port->port_list, &hsr->ports);
+	synchronize_rcu();
+
+	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+
+	/* Set required header length */
+	if (dev->hard_header_len + HSR_HLEN > master->dev->hard_header_len)
+		master->dev->hard_header_len = dev->hard_header_len + HSR_HLEN;
 
-	netdev_update_features(hsr->dev);
-	dev_set_mtu(hsr->dev, hsr_get_max_mtu(hsr));
+	dev_set_mtu(master->dev, hsr_get_max_mtu(hsr));
 
-	if (slave) {
-		netdev_rx_handler_unregister(slave);
-		dev_set_promiscuity(slave, -1);
+	return 0;
+
+fail_dev_setup:
+	kfree(port);
+	return res;
+}
+
+void hsr_del_port(struct hsr_port *port)
+{
+	struct hsr_priv *hsr;
+	struct hsr_port *master;
+
+	hsr = port->hsr;
+	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
+	list_del_rcu(&port->port_list);
+
+	if (port != master) {
+		dev_set_mtu(master->dev, hsr_get_max_mtu(hsr));
+		netdev_rx_handler_unregister(port->dev);
+		dev_set_promiscuity(port->dev, -1);
 	}
 
+	/* FIXME?
+	 * netdev_upper_dev_unlink(port->dev, port->hsr->dev);
+	 */
+
 	synchronize_rcu();
-	dev_put(slave);
+	dev_put(port->dev);
 }

net/hsr/hsr_slave.h

@@ -14,10 +14,35 @@
 
 #include <linux/skbuff.h>
 #include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
 #include "hsr_main.h"
 
-int hsr_add_slave(struct hsr_priv *hsr, struct net_device *dev, int idx);
-void hsr_del_slave(struct hsr_priv *hsr, int idx);
+int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev,
+		 enum hsr_port_type pt);
+void hsr_del_port(struct hsr_port *port);
 rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb);
 
+
+#define hsr_for_each_port(hsr, port) \
+	list_for_each_entry_rcu((port), &(hsr)->ports, port_list)
+
+
+static inline bool hsr_port_exists(const struct net_device *dev)
+{
+	return dev->rx_handler == hsr_handle_frame;
+}
+
+static inline struct hsr_port *hsr_port_get_rtnl(const struct net_device *dev)
+{
+	ASSERT_RTNL();
+	return hsr_port_exists(dev) ?
+				rtnl_dereference(dev->rx_handler_data) : NULL;
+}
+
+static inline struct hsr_port *hsr_port_get_rcu(const struct net_device *dev)
+{
+	return hsr_port_exists(dev) ?
+				rcu_dereference(dev->rx_handler_data) : NULL;
+}
+
 #endif /* __HSR_SLAVE_H */