diff --git a/include/uapi/linux/hsr_netlink.h b/include/uapi/linux/hsr_netlink.h
new file mode 100644
index 0000000..2475cb8
--- /dev/null
+++ b/include/uapi/linux/hsr_netlink.h
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2011-2013 Autronica Fire and Security AS
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * Author(s):
+ *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ */
+
+#ifndef __UAPI_HSR_NETLINK_H
+#define __UAPI_HSR_NETLINK_H
+
+/* Generic Netlink HSR family definition
+ */
+
+/* attributes */
+enum {
+	HSR_A_UNSPEC,
+	HSR_A_NODE_ADDR,
+	HSR_A_IFINDEX,
+	HSR_A_IF1_AGE,
+	HSR_A_IF2_AGE,
+	HSR_A_NODE_ADDR_B,
+	HSR_A_IF1_SEQ,
+	HSR_A_IF2_SEQ,
+	HSR_A_IF1_IFINDEX,
+	HSR_A_IF2_IFINDEX,
+	HSR_A_ADDR_B_IFINDEX,
+	__HSR_A_MAX,
+};
+#define HSR_A_MAX (__HSR_A_MAX - 1)
+
+
+/* commands */
+enum {
+	HSR_C_UNSPEC,
+	HSR_C_RING_ERROR,
+	HSR_C_NODE_DOWN,
+	HSR_C_GET_NODE_STATUS,
+	HSR_C_SET_NODE_STATUS,
+	HSR_C_GET_NODE_LIST,
+	HSR_C_SET_NODE_LIST,
+	__HSR_C_MAX,
+};
+#define HSR_C_MAX (__HSR_C_MAX - 1)
+
+#endif /* __UAPI_HSR_NETLINK_H */
diff --git a/include/uapi/linux/if_ether.h b/include/uapi/linux/if_ether.h
index ade07f1..2ce0f6a 100644
--- a/include/uapi/linux/if_ether.h
+++ b/include/uapi/linux/if_ether.h
@@ -85,6 +85,7 @@
 #define ETH_P_8021AH	0x88E7          /* 802.1ah Backbone Service Tag */
 #define ETH_P_MVRP	0x88F5          /* 802.1Q MVRP                  */
 #define ETH_P_1588	0x88F7		/* IEEE 1588 Timesync */
+#define ETH_P_PRP	0x88FB		/* IEC 62439-3 PRP/HSRv0	*/
 #define ETH_P_FCOE	0x8906		/* Fibre Channel over Ethernet  */
 #define ETH_P_TDLS	0x890D          /* TDLS */
 #define ETH_P_FIP	0x8914		/* FCoE Initialization Protocol */
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index 03f6170..5b164b4 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h
@@ -467,4 +467,17 @@ enum {
 
 #define IFLA_IPOIB_MAX (__IFLA_IPOIB_MAX - 1)
 
+
+/* HSR section */
+
+enum {
+	IFLA_HSR_UNSPEC,
+	IFLA_HSR_SLAVE1,
+	IFLA_HSR_SLAVE2,
+	IFLA_HSR_MULTICAST_SPEC,
+	__IFLA_HSR_MAX,
+};
+
+#define IFLA_HSR_MAX (__IFLA_HSR_MAX - 1)
+
 #endif /* _UAPI_LINUX_IF_LINK_H */
diff --git a/net/Kconfig b/net/Kconfig
index 51da839..e0c621a 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -219,6 +219,7 @@ source "net/openvswitch/Kconfig"
 source "net/vmw_vsock/Kconfig"
 source "net/netlink/Kconfig"
 source "net/mpls/Kconfig"
+source "net/hsr/Kconfig"
 
 config RPS
 	boolean
diff --git a/net/Makefile b/net/Makefile
index 9492e8c..8fa2f91 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -71,3 +71,4 @@ obj-$(CONFIG_NFC)		+= nfc/
 obj-$(CONFIG_OPENVSWITCH)	+= openvswitch/
 obj-$(CONFIG_VSOCKETS)	+= vmw_vsock/
 obj-$(CONFIG_NET_MPLS_GSO)	+= mpls/
+obj-$(CONFIG_HSR)		+= hsr/
diff --git a/net/hsr/Kconfig b/net/hsr/Kconfig
new file mode 100644
index 0000000..0d3d709
--- /dev/null
+++ b/net/hsr/Kconfig
@@ -0,0 +1,27 @@
+#
+# IEC 62439-3 High-availability Seamless Redundancy
+#
+
+config HSR
+	tristate "High-availability Seamless Redundancy (HSR)"
+	---help---
+	  If you say Y here, then your Linux box will be able to act as a
+	  DANH ("Doubly attached node implementing HSR"). For this to work,
+	  your Linux box needs (at least) two physical Ethernet interfaces,
+	  and it must be connected as a node in a ring network together with
+	  other HSR capable nodes.
+
+	  All Ethernet frames sent over the hsr device will be sent in both
+	  directions on the ring (over both slave ports), giving a redundant,
+	  instant fail-over network. Each HSR node in the ring acts like a
+	  bridge for HSR frames, but filters frames that have been forwarded
+	  earlier.
+
+	  This code is a "best effort" to comply with the HSR standard as
+	  described in IEC 62439-3:2010 (HSRv0), but no compliancy tests have
+	  been made.
+
+	  You need to perform any and all necessary tests yourself before
+	  relying on this code in a safety critical system!
+
+	  If unsure, say N.
diff --git a/net/hsr/Makefile b/net/hsr/Makefile
new file mode 100644
index 0000000..b68359f
--- /dev/null
+++ b/net/hsr/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for HSR
+#
+
+obj-$(CONFIG_HSR)	+= hsr.o
+
+hsr-y			:= hsr_main.o hsr_framereg.o hsr_device.o hsr_netlink.o
diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
new file mode 100644
index 0000000..78f356e
--- /dev/null
+++ b/net/hsr/hsr_device.c
@@ -0,0 +1,585 @@
+/*
+ * Copyright 2011-2013 Autronica Fire and Security AS
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * Author(s):
+ *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ *
+ * This file contains device methods for creating, using and destroying
+ * virtual HSR devices.
+ */
+
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <linux/etherdevice.h>
+#include <linux/if_arp.h>
+#include <linux/rtnetlink.h>
+#include <linux/pkt_sched.h>
+#include "hsr_device.h"
+#include "hsr_framereg.h"
+#include "hsr_main.h"
+
+
+static bool is_admin_up(struct net_device *dev)
+{
+	return dev && (dev->flags & IFF_UP);
+}
+
+static bool is_operstate_up(struct net_device *dev)
+{
+	return dev && netif_oper_up(dev);
+}
+
+static void __hsr_set_operstate(struct net_device *dev, int transition)
+{
+	if (dev->operstate != transition) {
+		write_lock_bh(&dev_base_lock);
+		dev->operstate = transition;
+		write_unlock_bh(&dev_base_lock);
+		netdev_state_change(dev);
+	}
+}
+
+void hsr_set_operstate(struct net_device *hsr_dev, struct net_device *slave1,
+		       struct net_device *slave2)
+{
+	if (!is_admin_up(hsr_dev)) {
+		__hsr_set_operstate(hsr_dev, IF_OPER_DOWN);
+		return;
+	}
+
+	if (is_operstate_up(slave1) || is_operstate_up(slave2))
+		__hsr_set_operstate(hsr_dev, IF_OPER_UP);
+	else
+		__hsr_set_operstate(hsr_dev, IF_OPER_LOWERLAYERDOWN);
+}
+
+void hsr_set_carrier(struct net_device *hsr_dev, struct net_device *slave1,
+		     struct net_device *slave2)
+{
+	if (is_operstate_up(slave1) || is_operstate_up(slave2))
+		netif_carrier_on(hsr_dev);
+	else
+		netif_carrier_off(hsr_dev);
+}
+
+
+void hsr_check_announce(struct net_device *hsr_dev, int old_operstate)
+{
+	struct hsr_priv *hsr_priv;
+
+	hsr_priv = netdev_priv(hsr_dev);
+
+	if ((hsr_dev->operstate == IF_OPER_UP) && (old_operstate != IF_OPER_UP)) {
+		/* Went up */
+		hsr_priv->announce_count = 0;
+		hsr_priv->announce_timer.expires = jiffies +
+				msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
+		add_timer(&hsr_priv->announce_timer);
+	}
+
+	if ((hsr_dev->operstate != IF_OPER_UP) && (old_operstate == IF_OPER_UP))
+		/* Went down */
+		del_timer(&hsr_priv->announce_timer);
+}
+
+
+int hsr_get_max_mtu(struct hsr_priv *hsr_priv)
+{
+	int mtu_max;
+
+	if (hsr_priv->slave[0] && hsr_priv->slave[1])
+		mtu_max = min(hsr_priv->slave[0]->mtu, hsr_priv->slave[1]->mtu);
+	else if (hsr_priv->slave[0])
+		mtu_max = hsr_priv->slave[0]->mtu;
+	else if (hsr_priv->slave[1])
+		mtu_max = hsr_priv->slave[1]->mtu;
+	else
+		mtu_max = HSR_TAGLEN;
+
+	return mtu_max - HSR_TAGLEN;
+}
+
+static int hsr_dev_change_mtu(struct net_device *dev, int new_mtu)
+{
+	struct hsr_priv *hsr_priv;
+
+	hsr_priv = netdev_priv(dev);
+
+	if (new_mtu > hsr_get_max_mtu(hsr_priv)) {
+		netdev_info(hsr_priv->dev, "A HSR master's MTU cannot be greater than the smallest MTU of its slaves minus the HSR Tag length (%d octets).\n",
+			    HSR_TAGLEN);
+		return -EINVAL;
+	}
+
+	dev->mtu = new_mtu;
+
+	return 0;
+}
+
+static int hsr_dev_open(struct net_device *dev)
+{
+	struct hsr_priv *hsr_priv;
+
+	hsr_priv = netdev_priv(dev);
+
+	if (hsr_priv->slave[0])
+		dev_open(hsr_priv->slave[0]);
+	if (hsr_priv->slave[1])
+		dev_open(hsr_priv->slave[1]);
+
+	return 0;
+}
+
+static int hsr_dev_close(struct net_device *dev)
+{
+	/* Nothing to do here. We could try to restore the state of the slaves
+	 * to what they were before being changed by the hsr master dev's state,
+	 * but they might have been changed manually in the mean time too, so
+	 * taking them up or down here might be confusing and is probably not a
+	 * good idea.
+	 */
+	return 0;
+}
+
+
+static void hsr_fill_tag(struct hsr_ethhdr *hsr_ethhdr, struct hsr_priv *hsr_priv)
+{
+	unsigned long irqflags;
+
+	/* IEC 62439-1:2010, p 48, says the 4-bit "path" field can take values
+	 * between 0001-1001 ("ring identifier", for regular HSR frames),
+	 * or 1111 ("HSR management", supervision frames). Unfortunately, the
+	 * spec writers forgot to explain what a "ring identifier" is, or
+	 * how it is used. So we just set this to 0001 for regular frames,
+	 * and 1111 for supervision frames.
+	 */
+	set_hsr_tag_path(&hsr_ethhdr->hsr_tag, 0x1);
+
+	/* IEC 62439-1:2010, p 12: "The link service data unit in an Ethernet
+	 * frame is the content of the frame located between the Length/Type
+	 * field and the Frame Check Sequence."
+	 *
+	 * IEC 62439-3, p 48, specifies the "original LPDU" to include the
+	 * original "LT" field (what "LT" means is not explained anywhere as
+	 * far as I can see - perhaps "Length/Type"?). So LSDU_size might
+	 * equal original length + 2.
+	 *   Also, the fact that this field is not used anywhere (might be used
+	 * by a RedBox connecting HSR and PRP nets?) means I cannot test its
+	 * correctness. Instead of guessing, I set this to 0 here, to make any
+	 * problems immediately apparent. Anyone using this driver with PRP/HSR
+	 * RedBoxes might need to fix this...
+	 */
+	set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, 0);
+
+	spin_lock_irqsave(&hsr_priv->seqnr_lock, irqflags);
+	hsr_ethhdr->hsr_tag.sequence_nr = htons(hsr_priv->sequence_nr);
+	hsr_priv->sequence_nr++;
+	spin_unlock_irqrestore(&hsr_priv->seqnr_lock, irqflags);
+
+	hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
+
+	hsr_ethhdr->ethhdr.h_proto = htons(ETH_P_PRP);
+}
+
+static int slave_xmit(struct sk_buff *skb, struct hsr_priv *hsr_priv,
+		      enum hsr_dev_idx dev_idx)
+{
+	struct hsr_ethhdr *hsr_ethhdr;
+
+	hsr_ethhdr = (struct hsr_ethhdr *) skb->data;
+
+	skb->dev = hsr_priv->slave[dev_idx];
+
+	hsr_addr_subst_dest(hsr_priv, &hsr_ethhdr->ethhdr, dev_idx);
+
+	/* Address substitution (IEC62439-3 pp 26, 50): replace mac
+	 * address of outgoing frame with that of the outgoing slave's.
+	 */
+	memcpy(hsr_ethhdr->ethhdr.h_source, skb->dev->dev_addr, ETH_ALEN);
+
+	return dev_queue_xmit(skb);
+}
+
+
+static int hsr_dev_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct hsr_priv *hsr_priv;
+	struct hsr_ethhdr *hsr_ethhdr;
+	struct sk_buff *skb2;
+	int res1, res2;
+
+	hsr_priv = netdev_priv(dev);
+	hsr_ethhdr = (struct hsr_ethhdr *) skb->data;
+
+	if ((skb->protocol != htons(ETH_P_PRP)) ||
+	    (hsr_ethhdr->ethhdr.h_proto != htons(ETH_P_PRP))) {
+		hsr_fill_tag(hsr_ethhdr, hsr_priv);
+		skb->protocol = htons(ETH_P_PRP);
+	}
+
+	skb2 = pskb_copy(skb, GFP_ATOMIC);
+
+	res1 = NET_XMIT_DROP;
+	if (likely(hsr_priv->slave[HSR_DEV_SLAVE_A]))
+		res1 = slave_xmit(skb, hsr_priv, HSR_DEV_SLAVE_A);
+
+	res2 = NET_XMIT_DROP;
+	if (likely(skb2 && hsr_priv->slave[HSR_DEV_SLAVE_B]))
+		res2 = slave_xmit(skb2, hsr_priv, HSR_DEV_SLAVE_B);
+
+	if (likely(res1 == NET_XMIT_SUCCESS || res1 == NET_XMIT_CN ||
+		   res2 == NET_XMIT_SUCCESS || res2 == NET_XMIT_CN)) {
+		hsr_priv->dev->stats.tx_packets++;
+		hsr_priv->dev->stats.tx_bytes += skb->len;
+	} else {
+		hsr_priv->dev->stats.tx_dropped++;
+	}
+
+	return NETDEV_TX_OK;
+}
+
+
+static int hsr_header_create(struct sk_buff *skb, struct net_device *dev,
+			     unsigned short type, const void *daddr,
+			     const void *saddr, unsigned int len)
+{
+	int res;
+
+	/* Make room for the HSR tag now. We will fill it in later (in
+	 * hsr_dev_xmit)
+	 */
+	if (skb_headroom(skb) < HSR_TAGLEN + ETH_HLEN)
+		return -ENOBUFS;
+	skb_push(skb, HSR_TAGLEN);
+
+	/* To allow VLAN/HSR combos we should probably use
+	 * res = dev_hard_header(skb, dev, type, daddr, saddr, len + HSR_TAGLEN);
+	 * here instead. It would require other changes too, though - e.g.
+	 * separate headers for each slave etc...
+	 */
+	res = eth_header(skb, dev, type, daddr, saddr, len + HSR_TAGLEN);
+	if (res <= 0)
+		return res;
+	skb_reset_mac_header(skb);
+
+	return res + HSR_TAGLEN;
+}
+
+
+static const struct header_ops hsr_header_ops = {
+	.create	 = hsr_header_create,
+	.parse	 = eth_header_parse,
+};
+
+
+/* HSR:2010 supervision frames should be padded so that the whole frame,
+ * including headers and FCS, is 64 bytes (without VLAN).
+ */
+static int hsr_pad(int size)
+{
+	const int min_size = ETH_ZLEN - HSR_TAGLEN - ETH_HLEN;
+
+	if (size >= min_size)
+		return size;
+	return min_size;
+}
+
+static void send_hsr_supervision_frame(struct net_device *hsr_dev, u8 type)
+{
+	struct hsr_priv *hsr_priv;
+	struct sk_buff *skb;
+	int hlen, tlen;
+	struct hsr_sup_tag *hsr_stag;
+	struct hsr_sup_payload *hsr_sp;
+	unsigned long irqflags;
+
+	hlen = LL_RESERVED_SPACE(hsr_dev);
+	tlen = hsr_dev->needed_tailroom;
+	skb = alloc_skb(hsr_pad(sizeof(struct hsr_sup_payload)) + hlen + tlen,
+			GFP_ATOMIC);
+
+	if (skb == NULL)
+		return;
+
+	hsr_priv = netdev_priv(hsr_dev);
+
+	skb_reserve(skb, hlen);
+
+	skb->dev = hsr_dev;
+	skb->protocol = htons(ETH_P_PRP);
+	skb->priority = TC_PRIO_CONTROL;
+
+	if (dev_hard_header(skb, skb->dev, ETH_P_PRP,
+			    hsr_priv->sup_multicast_addr,
+			    skb->dev->dev_addr, skb->len) < 0)
+		goto out;
+
+	skb_pull(skb, sizeof(struct ethhdr));
+	hsr_stag = (typeof(hsr_stag)) skb->data;
+
+	set_hsr_stag_path(hsr_stag, 0xf);
+	set_hsr_stag_HSR_Ver(hsr_stag, 0);
+
+	spin_lock_irqsave(&hsr_priv->seqnr_lock, irqflags);
+	hsr_stag->sequence_nr = htons(hsr_priv->sequence_nr);
+	hsr_priv->sequence_nr++;
+	spin_unlock_irqrestore(&hsr_priv->seqnr_lock, irqflags);
+
+	hsr_stag->HSR_TLV_Type = type;
+	hsr_stag->HSR_TLV_Length = 12;
+
+	skb_push(skb, sizeof(struct ethhdr));
+
+	/* Payload: MacAddressA */
+	hsr_sp = (typeof(hsr_sp)) skb_put(skb, sizeof(*hsr_sp));
+	memcpy(hsr_sp->MacAddressA, hsr_dev->dev_addr, ETH_ALEN);
+
+	dev_queue_xmit(skb);
+	return;
+
+out:
+	kfree_skb(skb);
+}
+
+
+/* Announce (supervision frame) timer function
+ */
+static void hsr_announce(unsigned long data)
+{
+	struct hsr_priv *hsr_priv;
+
+	hsr_priv = (struct hsr_priv *) data;
+
+	if (hsr_priv->announce_count < 3) {
+		send_hsr_supervision_frame(hsr_priv->dev, HSR_TLV_ANNOUNCE);
+		hsr_priv->announce_count++;
+	} else {
+		send_hsr_supervision_frame(hsr_priv->dev, HSR_TLV_LIFE_CHECK);
+	}
+
+	if (hsr_priv->announce_count < 3)
+		hsr_priv->announce_timer.expires = jiffies +
+				msecs_to_jiffies(HSR_ANNOUNCE_INTERVAL);
+	else
+		hsr_priv->announce_timer.expires = jiffies +
+				msecs_to_jiffies(HSR_LIFE_CHECK_INTERVAL);
+
+	if (is_admin_up(hsr_priv->dev))
+		add_timer(&hsr_priv->announce_timer);
+}
+
+
+static void restore_slaves(struct net_device *hsr_dev)
+{
+	struct hsr_priv *hsr_priv;
+	int i;
+	int res;
+
+	hsr_priv = netdev_priv(hsr_dev);
+
+	rtnl_lock();
+
+	/* Restore promiscuity */
+	for (i = 0; i < 2; i++) {
+		if (!hsr_priv->slave[i])
+			continue;
+		res = dev_set_promiscuity(hsr_priv->slave[i], -1);
+		if (res)
+			netdev_info(hsr_dev, "Cannot restore slave promiscuity (%s, %d)\n",
+				    hsr_priv->slave[i]->name, res);
+	}
+
+	rtnl_unlock();
+}
+
+static void reclaim_hsr_dev(struct rcu_head *rh)
+{
+	struct hsr_priv *hsr_priv;
+
+	hsr_priv = container_of(rh, struct hsr_priv, rcu_head);
+	free_netdev(hsr_priv->dev);
+}
+
+
+/* According to comments in the declaration of struct net_device, this function
+ * is "Called from unregister, can be used to call free_netdev". Ok then...
+ */
+static void hsr_dev_destroy(struct net_device *hsr_dev)
+{
+	struct hsr_priv *hsr_priv;
+
+	hsr_priv = netdev_priv(hsr_dev);
+
+	del_timer(&hsr_priv->announce_timer);
+	unregister_hsr_master(hsr_priv);    /* calls list_del_rcu on hsr_priv */
+	restore_slaves(hsr_dev);
+	call_rcu(&hsr_priv->rcu_head, reclaim_hsr_dev);   /* reclaim hsr_priv */
+}
+
+static const struct net_device_ops hsr_device_ops = {
+	.ndo_change_mtu = hsr_dev_change_mtu,
+	.ndo_open = hsr_dev_open,
+	.ndo_stop = hsr_dev_close,
+	.ndo_start_xmit = hsr_dev_xmit,
+};
+
+
+void hsr_dev_setup(struct net_device *dev)
+{
+	random_ether_addr(dev->dev_addr);
+
+	ether_setup(dev);
+	dev->header_ops		 = &hsr_header_ops;
+	dev->netdev_ops		 = &hsr_device_ops;
+	dev->tx_queue_len	 = 0;
+
+	dev->destructor = hsr_dev_destroy;
+}
+
+
+/* If dev is a HSR master, return 1; otherwise, return 0.
+ */
+bool is_hsr_master(struct net_device *dev)
+{
+	return (dev->netdev_ops->ndo_start_xmit == hsr_dev_xmit);
+}
+
+static int check_slave_ok(struct net_device *dev)
+{
+	/* Don't allow HSR on non-ethernet like devices */
+	if ((dev->flags & IFF_LOOPBACK) || (dev->type != ARPHRD_ETHER) ||
+	    (dev->addr_len != ETH_ALEN)) {
+		netdev_info(dev, "Cannot use loopback or non-ethernet device as HSR slave.\n");
+		return -EINVAL;
+	}
+
+	/* Don't allow enslaving hsr devices */
+	if (is_hsr_master(dev)) {
+		netdev_info(dev, "Cannot create trees of HSR devices.\n");
+		return -EINVAL;
+	}
+
+	if (is_hsr_slave(dev)) {
+		netdev_info(dev, "This device is already a HSR slave.\n");
+		return -EINVAL;
+	}
+
+	if (dev->priv_flags & IFF_802_1Q_VLAN) {
+		netdev_info(dev, "HSR on top of VLAN is not yet supported in this driver.\n");
+		return -EINVAL;
+	}
+
+	/* HSR over bonded devices has not been tested, but I'm not sure it
+	 * won't work...
+	 */
+
+	return 0;
+}
+
+
+/* Default multicast address for HSR Supervision frames */
+static const unsigned char def_multicast_addr[ETH_ALEN] = {
+	0x01, 0x15, 0x4e, 0x00, 0x01, 0x00
+};
+
+int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
+		     unsigned char multicast_spec)
+{
+	struct hsr_priv *hsr_priv;
+	int i;
+	int res;
+
+	hsr_priv = netdev_priv(hsr_dev);
+	hsr_priv->dev = hsr_dev;
+	INIT_LIST_HEAD(&hsr_priv->node_db);
+	INIT_LIST_HEAD(&hsr_priv->self_node_db);
+	for (i = 0; i < 2; i++)
+		hsr_priv->slave[i] = slave[i];
+
+	spin_lock_init(&hsr_priv->seqnr_lock);
+	/* Overflow soon to find bugs easier: */
+	hsr_priv->sequence_nr = USHRT_MAX - 1024;
+
+	init_timer(&hsr_priv->announce_timer);
+	hsr_priv->announce_timer.function = hsr_announce;
+	hsr_priv->announce_timer.data = (unsigned long) hsr_priv;
+
+	memcpy(hsr_priv->sup_multicast_addr, def_multicast_addr, ETH_ALEN);
+	hsr_priv->sup_multicast_addr[ETH_ALEN - 1] = multicast_spec;
+
+/* FIXME: should I modify the value of these?
+ *
+ * - hsr_dev->flags - i.e.
+ *			IFF_MASTER/SLAVE?
+ * - hsr_dev->priv_flags - i.e.
+ *			IFF_EBRIDGE?
+ *			IFF_TX_SKB_SHARING?
+ *			IFF_HSR_MASTER/SLAVE?
+ */
+
+	for (i = 0; i < 2; i++) {
+		res = check_slave_ok(slave[i]);
+		if (res)
+			return res;
+	}
+
+	hsr_dev->features = slave[0]->features & slave[1]->features;
+	/* Prevent recursive tx locking */
+	hsr_dev->features |= NETIF_F_LLTX;
+	/* VLAN on top of HSR needs testing and probably some work on
+	 * hsr_header_create() etc.
+	 */
+	hsr_dev->features |= NETIF_F_VLAN_CHALLENGED;
+
+	/* Set hsr_dev's MAC address to that of mac_slave1 */
+	memcpy(hsr_dev->dev_addr, hsr_priv->slave[0]->dev_addr, ETH_ALEN);
+
+	/* Set required header length */
+	for (i = 0; i < 2; i++)
+		if (slave[i]->hard_header_len + HSR_TAGLEN >
+						hsr_dev->hard_header_len)
+			hsr_dev->hard_header_len =
+					slave[i]->hard_header_len + HSR_TAGLEN;
+
+	/* MTU */
+	for (i = 0; i < 2; i++)
+		if (slave[i]->mtu - HSR_TAGLEN < hsr_dev->mtu)
+			hsr_dev->mtu = slave[i]->mtu - HSR_TAGLEN;
+
+	/* Make sure the 1st call to netif_carrier_on() gets through */
+	netif_carrier_off(hsr_dev);
+
+	/* Promiscuity */
+	for (i = 0; i < 2; i++) {
+		res = dev_set_promiscuity(slave[i], 1);
+		if (res) {
+			netdev_info(hsr_dev, "Cannot set slave promiscuity (%s, %d)\n",
+				    slave[i]->name, res);
+			goto fail;
+		}
+	}
+
+	/* Make sure we recognize frames from ourselves in hsr_rcv() */
+	res = hsr_create_self_node(&hsr_priv->self_node_db,
+					hsr_dev->dev_addr,
+					hsr_priv->slave[1]->dev_addr);
+	if (res < 0)
+		goto fail;
+
+	res = register_netdevice(hsr_dev);
+	if (res)
+		goto fail;
+
+	register_hsr_master(hsr_priv);
+
+	return 0;
+
+fail:
+	restore_slaves(hsr_dev);
+	return res;
+}
diff --git a/net/hsr/hsr_device.h b/net/hsr/hsr_device.h
new file mode 100644
index 0000000..549436a
--- /dev/null
+++ b/net/hsr/hsr_device.h
@@ -0,0 +1,30 @@
+/*
+ * Copyright 2011-2013 Autronica Fire and Security AS
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * Author(s):
+ *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ */
+
+#ifndef __HSR_DEVICE_H
+#define __HSR_DEVICE_H
+
+#include <linux/netdevice.h>
+#include "hsr_main.h"
+
+void hsr_dev_setup(struct net_device *dev);
+int hsr_dev_finalize(struct net_device *hsr_dev, struct net_device *slave[2],
+		     unsigned char multicast_spec);
+void hsr_set_operstate(struct net_device *hsr_dev, struct net_device *slave1,
+		       struct net_device *slave2);
+void hsr_set_carrier(struct net_device *hsr_dev, struct net_device *slave1,
+		     struct net_device *slave2);
+void hsr_check_announce(struct net_device *hsr_dev, int old_operstate);
+bool is_hsr_master(struct net_device *dev);
+int hsr_get_max_mtu(struct hsr_priv *hsr_priv);
+
+#endif /* __HSR_DEVICE_H */
diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c
new file mode 100644
index 0000000..51b1e53
--- /dev/null
+++ b/net/hsr/hsr_framereg.c
@@ -0,0 +1,502 @@
+/*
+ * Copyright 2011-2013 Autronica Fire and Security AS
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * Author(s):
+ *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ *
+ * The HSR spec says never to forward the same frame twice on the same
+ * interface. A frame is identified by its source MAC address and its HSR
+ * sequence number. This code keeps track of senders and their sequence numbers
+ * to allow filtering of duplicate frames, and to detect HSR ring errors.
+ */
+
+#include <linux/if_ether.h>
+#include <linux/etherdevice.h>
+#include <linux/slab.h>
+#include <linux/rculist.h>
+#include "hsr_main.h"
+#include "hsr_framereg.h"
+#include "hsr_netlink.h"
+
+
+struct node_entry {
+	struct list_head mac_list;
+	unsigned char	MacAddressA[ETH_ALEN];
+	unsigned char	MacAddressB[ETH_ALEN];
+	enum hsr_dev_idx   AddrB_if;	/* The local slave through which AddrB
+					 * frames are received from this node
+					 */
+	unsigned long	time_in[HSR_MAX_SLAVE];
+	bool		time_in_stale[HSR_MAX_SLAVE];
+	u16		seq_out[HSR_MAX_DEV];
+	struct rcu_head rcu_head;
+};
+
+/*	TODO: use hash lists for mac addresses (linux/jhash.h)?    */
+
+
+
+/* Search for mac entry. Caller must hold rcu read lock.
+ */
+static struct node_entry *find_node_by_AddrA(struct list_head *node_db,
+					     const unsigned char addr[ETH_ALEN])
+{
+	struct node_entry *node;
+
+	list_for_each_entry_rcu(node, node_db, mac_list) {
+		if (!compare_ether_addr(node->MacAddressA, addr))
+			return node;
+	}
+
+	return NULL;
+}
+
+
+/* Search for mac entry. Caller must hold rcu read lock.
+ */
+static struct node_entry *find_node_by_AddrB(struct list_head *node_db,
+					     const unsigned char addr[ETH_ALEN])
+{
+	struct node_entry *node;
+
+	list_for_each_entry_rcu(node, node_db, mac_list) {
+		if (!compare_ether_addr(node->MacAddressB, addr))
+			return node;
+	}
+
+	return NULL;
+}
+
+
+/* Search for mac entry. Caller must hold rcu read lock.
+ */
+struct node_entry *hsr_find_node(struct list_head *node_db, struct sk_buff *skb)
+{
+	struct node_entry *node;
+	struct ethhdr *ethhdr;
+
+	if (!skb_mac_header_was_set(skb))
+		return NULL;
+
+	ethhdr = (struct ethhdr *) skb_mac_header(skb);
+
+	list_for_each_entry_rcu(node, node_db, mac_list) {
+		if (!compare_ether_addr(node->MacAddressA, ethhdr->h_source))
+			return node;
+		if (!compare_ether_addr(node->MacAddressB, ethhdr->h_source))
+			return node;
+	}
+
+	return NULL;
+}
+
+
+/* Helper for device init; the self_node_db is used in hsr_rcv() to recognize
+ * frames from self that's been looped over the HSR ring.
+ */
+int hsr_create_self_node(struct list_head *self_node_db,
+			 unsigned char addr_a[ETH_ALEN],
+			 unsigned char addr_b[ETH_ALEN])
+{
+	struct node_entry *node, *oldnode;
+
+	node = kmalloc(sizeof(*node), GFP_KERNEL);
+	if (!node)
+		return -ENOMEM;
+
+	memcpy(node->MacAddressA, addr_a, ETH_ALEN);
+	memcpy(node->MacAddressB, addr_b, ETH_ALEN);
+
+	rcu_read_lock();
+	oldnode = list_first_or_null_rcu(self_node_db,
+						struct node_entry, mac_list);
+	if (oldnode) {
+		list_replace_rcu(&oldnode->mac_list, &node->mac_list);
+		rcu_read_unlock();
+		synchronize_rcu();
+		kfree(oldnode);
+	} else {
+		rcu_read_unlock();
+		list_add_tail_rcu(&node->mac_list, self_node_db);
+	}
+
+	return 0;
+}
+
+static void node_entry_reclaim(struct rcu_head *rh)
+{
+	kfree(container_of(rh, struct node_entry, rcu_head));
+}
+
+
+/* Add/merge node to the database of nodes. 'skb' must contain an HSR
+ * supervision frame.
+ * - If the supervision header's MacAddressA field is not yet in the database,
+ * this frame is from an hitherto unknown node - add it to the database.
+ * - If the sender's MAC address is not the same as its MacAddressA address,
+ * the node is using PICS_SUBS (address substitution). Record the sender's
+ * address as the node's MacAddressB.
+ *
+ * This function needs to work even if the sender node has changed one of its
+ * slaves' MAC addresses. In this case, there are four different cases described
+ * by (Addr-changed, received-from) pairs as follows. Note that changing the
+ * SlaveA address is equal to changing the node's own address:
+ *
+ * - (AddrB, SlaveB): The new AddrB will be recorded by PICS_SUBS code since
+ *		      node == NULL.
+ * - (AddrB, SlaveA): Will work as usual (the AddrB change won't be detected
+ *		      from this frame).
+ *
+ * - (AddrA, SlaveB): The old node will be found. We need to detect this and
+ *		      remove the node.
+ * - (AddrA, SlaveA): A new node will be registered (non-PICS_SUBS at first).
+ *		      The old one will be pruned after HSR_NODE_FORGET_TIME.
+ *
+ * We also need to detect if the sender's SlaveA and SlaveB cables have been
+ * swapped.
+ */
+struct node_entry *hsr_merge_node(struct hsr_priv *hsr_priv,
+				  struct node_entry *node,
+				  struct sk_buff *skb,
+				  enum hsr_dev_idx dev_idx)
+{
+	struct hsr_sup_payload *hsr_sp;
+	struct hsr_ethhdr_sp *hsr_ethsup;
+	int i;
+	unsigned long now;
+
+	hsr_ethsup = (struct hsr_ethhdr_sp *) skb_mac_header(skb);
+	hsr_sp = (struct hsr_sup_payload *) skb->data;
+
+	if (node && compare_ether_addr(node->MacAddressA, hsr_sp->MacAddressA)) {
+		/* Node has changed its AddrA, frame was received from SlaveB */
+		list_del_rcu(&node->mac_list);
+		call_rcu(&node->rcu_head, node_entry_reclaim);
+		node = NULL;
+	}
+
+	if (node && (dev_idx == node->AddrB_if) &&
+	    compare_ether_addr(node->MacAddressB, hsr_ethsup->ethhdr.h_source)) {
+		/* Cables have been swapped */
+		list_del_rcu(&node->mac_list);
+		call_rcu(&node->rcu_head, node_entry_reclaim);
+		node = NULL;
+	}
+
+	if (node && (dev_idx != node->AddrB_if) &&
+	    (node->AddrB_if != HSR_DEV_NONE) &&
+	    compare_ether_addr(node->MacAddressA, hsr_ethsup->ethhdr.h_source)) {
+		/* Cables have been swapped */
+		list_del_rcu(&node->mac_list);
+		call_rcu(&node->rcu_head, node_entry_reclaim);
+		node = NULL;
+	}
+
+	if (node)
+		return node;
+
+	node = find_node_by_AddrA(&hsr_priv->node_db, hsr_sp->MacAddressA);
+	if (node) {
+		/* Node is known, but frame was received from an unknown
+		 * address. Node is PICS_SUBS capable; merge its AddrB.
+		 */
+		memcpy(node->MacAddressB, hsr_ethsup->ethhdr.h_source, ETH_ALEN);
+		node->AddrB_if = dev_idx;
+		return node;
+	}
+
+	node = kzalloc(sizeof(*node), GFP_ATOMIC);
+	if (!node)
+		return NULL;
+
+	memcpy(node->MacAddressA, hsr_sp->MacAddressA, ETH_ALEN);
+	memcpy(node->MacAddressB, hsr_ethsup->ethhdr.h_source, ETH_ALEN);
+	if (compare_ether_addr(hsr_sp->MacAddressA, hsr_ethsup->ethhdr.h_source))
+		node->AddrB_if = dev_idx;
+	else
+		node->AddrB_if = HSR_DEV_NONE;
+
+	/* We are only interested in time diffs here, so use current jiffies
+	 * as initialization. (0 could trigger an spurious ring error warning).
+	 */
+	now = jiffies;
+	for (i = 0; i < HSR_MAX_SLAVE; i++)
+		node->time_in[i] = now;
+	for (i = 0; i < HSR_MAX_DEV; i++)
+		node->seq_out[i] = ntohs(hsr_ethsup->hsr_sup.sequence_nr) - 1;
+
+	list_add_tail_rcu(&node->mac_list, &hsr_priv->node_db);
+
+	return node;
+}
+
+
+/* 'skb' is a frame meant for this host, that is to be passed to upper layers.
+ *
+ * If the frame was sent by a node's B interface, replace the sender
+ * address with that node's "official" address (MacAddressA) so that upper
+ * layers recognize where it came from.
+ */
+void hsr_addr_subst_source(struct hsr_priv *hsr_priv, struct sk_buff *skb)
+{
+	struct ethhdr *ethhdr;
+	struct node_entry *node;
+
+	if (!skb_mac_header_was_set(skb)) {
+		WARN_ONCE(1, "%s: Mac header not set\n", __func__);
+		return;
+	}
+	ethhdr = (struct ethhdr *) skb_mac_header(skb);
+
+	rcu_read_lock();
+	node = find_node_by_AddrB(&hsr_priv->node_db, ethhdr->h_source);
+	if (node)
+		memcpy(ethhdr->h_source, node->MacAddressA, ETH_ALEN);
+	rcu_read_unlock();
+}
+
+
+/* 'skb' is a frame meant for another host.
+ * 'hsr_dev_idx' is the HSR index of the outgoing device
+ *
+ * Substitute the target (dest) MAC address if necessary, so the it matches the
+ * recipient interface MAC address, regardless of whether that is the
+ * recipient's A or B interface.
+ * This is needed to keep the packets flowing through switches that learn on
+ * which "side" the different interfaces are.
+ */
+void hsr_addr_subst_dest(struct hsr_priv *hsr_priv, struct ethhdr *ethhdr,
+			 enum hsr_dev_idx dev_idx)
+{
+	struct node_entry *node;
+
+	rcu_read_lock();
+	node = find_node_by_AddrA(&hsr_priv->node_db, ethhdr->h_dest);
+	if (node && (node->AddrB_if == dev_idx))
+		memcpy(ethhdr->h_dest, node->MacAddressB, ETH_ALEN);
+	rcu_read_unlock();
+}
+
+
+/* above(a, b) - return 1 if a > b, 0 otherwise.
+ */
+static bool above(u16 a, u16 b)
+{
+	/* Remove inconsistency where above(a, b) == below(a, b) */
+	if ((int) b - a == 32768)
+		return 0;
+
+	return (((s16) (b - a)) < 0);
+}
+#define below(a, b)		above((b), (a))
+#define above_or_eq(a, b)	(!below((a), (b)))
+#define below_or_eq(a, b)	(!above((a), (b)))
+
+
+void hsr_register_frame_in(struct node_entry *node, enum hsr_dev_idx dev_idx)
+{
+	if ((dev_idx < 0) || (dev_idx >= HSR_MAX_DEV)) {
+		WARN_ONCE(1, "%s: Invalid dev_idx (%d)\n", __func__, dev_idx);
+		return;
+	}
+	node->time_in[dev_idx] = jiffies;
+	node->time_in_stale[dev_idx] = 0;
+}
+
+
+/* 'skb' is a HSR Ethernet frame (with a HSR tag inserted), with a valid
+ * ethhdr->h_source address and skb->mac_header set.
+ *
+ * Return:
+ *	 1 if frame can be shown to have been sent recently on this interface,
+ *	 0 otherwise, or
+ *	 negative error code on error
+ */
+int hsr_register_frame_out(struct node_entry *node, enum hsr_dev_idx dev_idx,
+			   struct sk_buff *skb)
+{
+	struct hsr_ethhdr *hsr_ethhdr;
+	u16 sequence_nr;
+
+	if ((dev_idx < 0) || (dev_idx >= HSR_MAX_DEV)) {
+		WARN_ONCE(1, "%s: Invalid dev_idx (%d)\n", __func__, dev_idx);
+		return -EINVAL;
+	}
+	if (!skb_mac_header_was_set(skb)) {
+		WARN_ONCE(1, "%s: Mac header not set\n", __func__);
+		return -EINVAL;
+	}
+	hsr_ethhdr = (struct hsr_ethhdr *) skb_mac_header(skb);
+
+	sequence_nr = ntohs(hsr_ethhdr->hsr_tag.sequence_nr);
+	if (below_or_eq(sequence_nr, node->seq_out[dev_idx]))
+		return 1;
+
+	node->seq_out[dev_idx] = sequence_nr;
+	return 0;
+}
+
+
+
+static bool is_late(struct node_entry *node, enum hsr_dev_idx dev_idx)
+{
+	enum hsr_dev_idx other;
+
+	if (node->time_in_stale[dev_idx])
+		return 1;
+
+	if (dev_idx == HSR_DEV_SLAVE_A)
+		other = HSR_DEV_SLAVE_B;
+	else
+		other = HSR_DEV_SLAVE_A;
+
+	if (node->time_in_stale[other])
+		return 0;
+
+	if (time_after(node->time_in[other], node->time_in[dev_idx] +
+		       msecs_to_jiffies(MAX_SLAVE_DIFF)))
+		return 1;
+
+	return 0;
+}
+
+
+/* Remove stale sequence_nr records. Called by timer every
+ * HSR_LIFE_CHECK_INTERVAL (two seconds or so).
+ */
+void hsr_prune_nodes(struct hsr_priv *hsr_priv)
+{
+	struct node_entry *node;
+	unsigned long timestamp;
+	unsigned long time_a, time_b;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(node, &hsr_priv->node_db, mac_list) {
+		/* Shorthand */
+		time_a = node->time_in[HSR_DEV_SLAVE_A];
+		time_b = node->time_in[HSR_DEV_SLAVE_B];
+
+		/* Check for timestamps old enough to risk wrap-around */
+		if (time_after(jiffies, time_a + MAX_JIFFY_OFFSET/2))
+			node->time_in_stale[HSR_DEV_SLAVE_A] = 1;
+		if (time_after(jiffies, time_b + MAX_JIFFY_OFFSET/2))
+			node->time_in_stale[HSR_DEV_SLAVE_B] = 1;
+
+		/* Get age of newest frame from node.
+		 * At least one time_in is OK here; nodes get pruned long
+		 * before both time_ins can get stale
+		 */
+		timestamp = time_a;
+		if (node->time_in_stale[HSR_DEV_SLAVE_A] ||
+		    (!node->time_in_stale[HSR_DEV_SLAVE_B] &&
+		    time_after(time_b, time_a)))
+			timestamp = time_b;
+
+		/* Warn of ring error only as long as we get frames at all */
+		if (time_is_after_jiffies(timestamp +
+					msecs_to_jiffies(1.5*MAX_SLAVE_DIFF))) {
+
+			if (is_late(node, HSR_DEV_SLAVE_A))
+				hsr_nl_ringerror(hsr_priv, node->MacAddressA,
+						 HSR_DEV_SLAVE_A);
+			else if (is_late(node, HSR_DEV_SLAVE_B))
+				hsr_nl_ringerror(hsr_priv, node->MacAddressA,
+						 HSR_DEV_SLAVE_B);
+		}
+
+		/* Prune old entries */
+		if (time_is_before_jiffies(timestamp +
+					msecs_to_jiffies(HSR_NODE_FORGET_TIME))) {
+			hsr_nl_nodedown(hsr_priv, node->MacAddressA);
+			list_del_rcu(&node->mac_list);
+			/* Note that we need to free this entry later: */
+			call_rcu(&node->rcu_head, node_entry_reclaim);
+		}
+	}
+	rcu_read_unlock();
+}
+
+
+void *hsr_get_next_node(struct hsr_priv *hsr_priv, void *_pos,
+			unsigned char addr[ETH_ALEN])
+{
+	struct node_entry *node;
+
+	if (!_pos) {
+		node = list_first_or_null_rcu(&hsr_priv->node_db,
+						struct node_entry, mac_list);
+		if (node)
+			memcpy(addr, node->MacAddressA, ETH_ALEN);
+		return node;
+	}
+
+	node = _pos;
+	list_for_each_entry_continue_rcu(node, &hsr_priv->node_db, mac_list) {
+		memcpy(addr, node->MacAddressA, ETH_ALEN);
+		return node;
+	}
+
+	return NULL;
+}
+
+
+int hsr_get_node_data(struct hsr_priv *hsr_priv,
+		      const unsigned char *addr,
+		      unsigned char addr_b[ETH_ALEN],
+		      unsigned int *addr_b_ifindex,
+		      int *if1_age,
+		      u16 *if1_seq,
+		      int *if2_age,
+		      u16 *if2_seq)
+{
+	struct node_entry *node;
+	unsigned long tdiff;
+
+
+	rcu_read_lock();
+	node = find_node_by_AddrA(&hsr_priv->node_db, addr);
+	if (!node) {
+		rcu_read_unlock();
+		return -ENOENT;	/* No such entry */
+	}
+
+	memcpy(addr_b, node->MacAddressB, ETH_ALEN);
+
+	tdiff = jiffies - node->time_in[HSR_DEV_SLAVE_A];
+	if (node->time_in_stale[HSR_DEV_SLAVE_A])
+		*if1_age = INT_MAX;
+#if HZ <= MSEC_PER_SEC
+	else if (tdiff > msecs_to_jiffies(INT_MAX))
+		*if1_age = INT_MAX;
+#endif
+	else
+		*if1_age = jiffies_to_msecs(tdiff);
+
+	tdiff = jiffies - node->time_in[HSR_DEV_SLAVE_B];
+	if (node->time_in_stale[HSR_DEV_SLAVE_B])
+		*if2_age = INT_MAX;
+#if HZ <= MSEC_PER_SEC
+	else if (tdiff > msecs_to_jiffies(INT_MAX))
+		*if2_age = INT_MAX;
+#endif
+	else
+		*if2_age = jiffies_to_msecs(tdiff);
+
+	/* Present sequence numbers as if they were incoming on interface */
+	*if1_seq = node->seq_out[HSR_DEV_SLAVE_B];
+	*if2_seq = node->seq_out[HSR_DEV_SLAVE_A];
+
+	if ((node->AddrB_if != HSR_DEV_NONE) && hsr_priv->slave[node->AddrB_if])
+		*addr_b_ifindex = hsr_priv->slave[node->AddrB_if]->ifindex;
+	else
+		*addr_b_ifindex = -1;
+
+	rcu_read_unlock();
+
+	return 0;
+}
diff --git a/net/hsr/hsr_framereg.h b/net/hsr/hsr_framereg.h
new file mode 100644
index 0000000..0db42ca
--- /dev/null
+++ b/net/hsr/hsr_framereg.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2011-2013 Autronica Fire and Security AS
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * Author(s):
+ *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ */
+
+#ifndef _HSR_FRAMEREG_H
+#define _HSR_FRAMEREG_H
+
+#include "hsr_main.h"
+
+struct node_entry;
+
+struct node_entry *hsr_find_node(struct list_head *node_db, struct sk_buff *skb);
+
+struct node_entry *hsr_merge_node(struct hsr_priv *hsr_priv,
+				  struct node_entry *node,
+				  struct sk_buff *skb,
+				  enum hsr_dev_idx dev_idx);
+
+void hsr_addr_subst_source(struct hsr_priv *hsr_priv, struct sk_buff *skb);
+void hsr_addr_subst_dest(struct hsr_priv *hsr_priv, struct ethhdr *ethhdr,
+			 enum hsr_dev_idx dev_idx);
+
+void hsr_register_frame_in(struct node_entry *node, enum hsr_dev_idx dev_idx);
+
+int hsr_register_frame_out(struct node_entry *node, enum hsr_dev_idx dev_idx,
+			   struct sk_buff *skb);
+
+void hsr_prune_nodes(struct hsr_priv *hsr_priv);
+
+int hsr_create_self_node(struct list_head *self_node_db,
+			 unsigned char addr_a[ETH_ALEN],
+			 unsigned char addr_b[ETH_ALEN]);
+
+void *hsr_get_next_node(struct hsr_priv *hsr_priv, void *_pos,
+			unsigned char addr[ETH_ALEN]);
+
+int hsr_get_node_data(struct hsr_priv *hsr_priv,
+		      const unsigned char *addr,
+		      unsigned char addr_b[ETH_ALEN],
+		      unsigned int *addr_b_ifindex,
+		      int *if1_age,
+		      u16 *if1_seq,
+		      int *if2_age,
+		      u16 *if2_seq);
+
+#endif /* _HSR_FRAMEREG_H */
diff --git a/net/hsr/hsr_main.c b/net/hsr/hsr_main.c
new file mode 100644
index 0000000..ebca843
--- /dev/null
+++ b/net/hsr/hsr_main.c
@@ -0,0 +1,457 @@
+/*
+ * Copyright 2011-2013 Autronica Fire and Security AS
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * Author(s):
+ *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ *
+ * In addition to routines for registering and unregistering HSR support, this
+ * file also contains the receive routine that handles all incoming frames with
+ * Ethertype (protocol) ETH_P_PRP (HSRv0), and network device event handling.
+ */
+
+#include <linux/netdevice.h>
+#include <linux/rculist.h>
+#include <linux/timer.h>
+#include <linux/etherdevice.h>
+#include "hsr_main.h"
+#include "hsr_device.h"
+#include "hsr_netlink.h"
+#include "hsr_framereg.h"
+
+
+/* List of all registered virtual HSR devices */
+static LIST_HEAD(hsr_list);
+
+void register_hsr_master(struct hsr_priv *hsr_priv)
+{
+	list_add_tail_rcu(&hsr_priv->hsr_list, &hsr_list);
+}
+
+void unregister_hsr_master(struct hsr_priv *hsr_priv)
+{
+	struct hsr_priv *hsr_priv_it;
+
+	list_for_each_entry(hsr_priv_it, &hsr_list, hsr_list)
+		if (hsr_priv_it == hsr_priv) {
+			list_del_rcu(&hsr_priv_it->hsr_list);
+			return;
+		}
+}
+
+bool is_hsr_slave(struct net_device *dev)
+{
+	struct hsr_priv *hsr_priv_it;
+
+	list_for_each_entry_rcu(hsr_priv_it, &hsr_list, hsr_list) {
+		if (dev == hsr_priv_it->slave[0])
+			return true;
+		if (dev == hsr_priv_it->slave[1])
+			return true;
+	}
+
+	return false;
+}
+
+
+/* If dev is a HSR slave device, return the virtual master device. Return NULL
+ * otherwise.
+ */
+static struct hsr_priv *get_hsr_master(struct net_device *dev)
+{
+	struct hsr_priv *hsr_priv;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(hsr_priv, &hsr_list, hsr_list)
+		if ((dev == hsr_priv->slave[0]) ||
+		    (dev == hsr_priv->slave[1])) {
+			rcu_read_unlock();
+			return hsr_priv;
+		}
+
+	rcu_read_unlock();
+	return NULL;
+}
+
+
+/* If dev is a HSR slave device, return the other slave device. Return NULL
+ * otherwise.
+ */
+static struct net_device *get_other_slave(struct hsr_priv *hsr_priv,
+					  struct net_device *dev)
+{
+	if (dev == hsr_priv->slave[0])
+		return hsr_priv->slave[1];
+	if (dev == hsr_priv->slave[1])
+		return hsr_priv->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 hsr_priv *hsr_priv;
+	int old_operstate;
+	int mtu_max;
+	int res;
+	struct net_device *dev;
+
+	dev = netdev_notifier_info_to_dev(ptr);
+
+	hsr_priv = get_hsr_master(dev);
+	if (hsr_priv) {
+		/* dev is a slave device */
+		slave = dev;
+		other_slave = get_other_slave(hsr_priv, slave);
+	} else {
+		if (!is_hsr_master(dev))
+			return NOTIFY_DONE;
+		hsr_priv = netdev_priv(dev);
+		slave = hsr_priv->slave[0];
+		other_slave = hsr_priv->slave[1];
+	}
+
+	switch (event) {
+	case NETDEV_UP:		/* Administrative state DOWN */
+	case NETDEV_DOWN:	/* Administrative state UP */
+	case NETDEV_CHANGE:	/* Link (carrier) state changes */
+		old_operstate = hsr_priv->dev->operstate;
+		hsr_set_carrier(hsr_priv->dev, slave, other_slave);
+		/* netif_stacked_transfer_operstate() cannot be used here since
+		 * it doesn't set IF_OPER_LOWERLAYERDOWN (?)
+		 */
+		hsr_set_operstate(hsr_priv->dev, slave, other_slave);
+		hsr_check_announce(hsr_priv->dev, old_operstate);
+		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_priv->dev)
+			break;
+		if (dev == hsr_priv->slave[0])
+			memcpy(hsr_priv->dev->dev_addr,
+			       hsr_priv->slave[0]->dev_addr, ETH_ALEN);
+
+		/* Make sure we recognize frames from ourselves in hsr_rcv() */
+		res = hsr_create_self_node(&hsr_priv->self_node_db,
+					   hsr_priv->dev->dev_addr,
+					   hsr_priv->slave[1] ?
+						hsr_priv->slave[1]->dev_addr :
+						hsr_priv->dev->dev_addr);
+		if (res)
+			netdev_warn(hsr_priv->dev,
+				    "Could not update HSR node address.\n");
+
+		if (dev == hsr_priv->slave[0])
+			call_netdevice_notifiers(NETDEV_CHANGEADDR, hsr_priv->dev);
+		break;
+	case NETDEV_CHANGEMTU:
+		if (dev == hsr_priv->dev)
+			break; /* Handled in ndo_change_mtu() */
+		mtu_max = hsr_get_max_mtu(hsr_priv);
+		if (hsr_priv->dev->mtu > mtu_max)
+			dev_set_mtu(hsr_priv->dev, mtu_max);
+		break;
+	case NETDEV_UNREGISTER:
+		if (dev == hsr_priv->slave[0])
+			hsr_priv->slave[0] = NULL;
+		if (dev == hsr_priv->slave[1])
+			hsr_priv->slave[1] = NULL;
+
+		/* There should really be a way to set a new slave device... */
+
+		break;
+	case NETDEV_PRE_TYPE_CHANGE:
+		/* HSR works only on Ethernet devices. Refuse slave to change
+		 * its type.
+		 */
+		return NOTIFY_BAD;
+	}
+
+	return NOTIFY_DONE;
+}
+
+
+static struct timer_list prune_timer;
+
+static void prune_nodes_all(unsigned long data)
+{
+	struct hsr_priv *hsr_priv;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(hsr_priv, &hsr_list, hsr_list)
+		hsr_prune_nodes(hsr_priv);
+	rcu_read_unlock();
+
+	prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
+	add_timer(&prune_timer);
+}
+
+
+static struct sk_buff *strip_hsr_tag(struct sk_buff *skb)
+{
+	struct hsr_tag *hsr_tag;
+	struct sk_buff *skb2;
+
+	skb2 = skb_share_check(skb, GFP_ATOMIC);
+	if (unlikely(!skb2))
+		goto err_free;
+	skb = skb2;
+
+	if (unlikely(!pskb_may_pull(skb, HSR_TAGLEN)))
+		goto err_free;
+
+	hsr_tag = (struct hsr_tag *) skb->data;
+	skb->protocol = hsr_tag->encap_proto;
+	skb_pull(skb, HSR_TAGLEN);
+
+	return skb;
+
+err_free:
+	kfree_skb(skb);
+	return NULL;
+}
+
+
+/* The uses I can see for these HSR supervision frames are:
+ * 1) Use the frames that are sent after node initialization ("HSR_TLV.Type =
+ *    22") to reset any sequence_nr counters belonging to that node. Useful if
+ *    the other node's counter has been reset for some reason.
+ *    --
+ *    Or not - resetting the counter and bridging the frame would create a
+ *    loop, unfortunately.
+ *
+ * 2) Use the LifeCheck frames to detect ring breaks. I.e. if no LifeCheck
+ *    frame is received from a particular node, we know something is wrong.
+ *    We just register these (as with normal frames) and throw them away.
+ *
+ * 3) Allow different MAC addresses for the two slave interfaces, using the
+ *    MacAddressA field.
+ */
+static bool is_supervision_frame(struct hsr_priv *hsr_priv, struct sk_buff *skb)
+{
+	struct hsr_sup_tag *hsr_stag;
+
+	if (compare_ether_addr(eth_hdr(skb)->h_dest,
+			       hsr_priv->sup_multicast_addr))
+		return 0;
+
+	hsr_stag = (struct hsr_sup_tag *) skb->data;
+	if (get_hsr_stag_path(hsr_stag) != 0x0f)
+		return 0;
+	if ((hsr_stag->HSR_TLV_Type != HSR_TLV_ANNOUNCE) &&
+	    (hsr_stag->HSR_TLV_Type != HSR_TLV_LIFE_CHECK))
+		return 0;
+	if (hsr_stag->HSR_TLV_Length != 12)
+		return 0;
+
+	return 1;
+}
+
+
+/* Implementation somewhat according to IEC-62439-3, p. 43
+ */
+static int hsr_rcv(struct sk_buff *skb, struct net_device *dev,
+		   struct packet_type *pt, struct net_device *orig_dev)
+{
+	struct hsr_priv *hsr_priv;
+	struct net_device *other_slave;
+	struct node_entry *node;
+	int deliver_to_self;
+	struct sk_buff *skb_deliver;
+	enum hsr_dev_idx dev_in_idx, dev_other_idx;
+	bool dup_out;
+	int ret;
+
+	hsr_priv = get_hsr_master(dev);
+
+	if (!hsr_priv) {
+		/* Non-HSR-slave device 'dev' is connected to a HSR network */
+		kfree_skb(skb);
+		dev->stats.rx_errors++;
+		return NET_RX_SUCCESS;
+	}
+
+	if (dev == hsr_priv->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;
+	}
+
+	node = hsr_find_node(&hsr_priv->self_node_db, skb);
+	if (node) {
+		/* Always kill frames sent by ourselves */
+		kfree_skb(skb);
+		return NET_RX_SUCCESS;
+	}
+
+	/* Is this frame a candidate for local reception? */
+	deliver_to_self = 0;
+	if ((skb->pkt_type == PACKET_HOST) ||
+	    (skb->pkt_type == PACKET_MULTICAST) ||
+	    (skb->pkt_type == PACKET_BROADCAST))
+		deliver_to_self = 1;
+	else if (!compare_ether_addr(eth_hdr(skb)->h_dest,
+				     hsr_priv->dev->dev_addr)) {
+		skb->pkt_type = PACKET_HOST;
+		deliver_to_self = 1;
+	}
+
+
+	rcu_read_lock(); /* node_db */
+	node = hsr_find_node(&hsr_priv->node_db, skb);
+
+	if (is_supervision_frame(hsr_priv, skb)) {
+		skb_pull(skb, sizeof(struct hsr_sup_tag));
+		node = hsr_merge_node(hsr_priv, node, skb, dev_in_idx);
+		if (!node) {
+			rcu_read_unlock(); /* node_db */
+			kfree_skb(skb);
+			hsr_priv->dev->stats.rx_dropped++;
+			return NET_RX_DROP;
+		}
+		skb_push(skb, sizeof(struct hsr_sup_tag));
+		deliver_to_self = 0;
+	}
+
+	if (!node) {
+		/* 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 NET_RX_SUCCESS;
+	}
+
+	/* 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 (!dup_out)
+		hsr_register_frame_in(node, dev_in_idx);
+
+	/* Forward this frame? */
+	if (!dup_out && (skb->pkt_type != PACKET_HOST))
+		other_slave = get_other_slave(hsr_priv, dev);
+	else
+		other_slave = NULL;
+
+	if (hsr_register_frame_out(node, HSR_DEV_MASTER, skb))
+		deliver_to_self = 0;
+
+	rcu_read_unlock(); /* node_db */
+
+	if (!deliver_to_self && !other_slave) {
+		kfree_skb(skb);
+		/* Circulated frame; silently remove it. */
+		return NET_RX_SUCCESS;
+	}
+
+	skb_deliver = skb;
+	if (deliver_to_self && other_slave) {
+		/* 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 = 0;
+			hsr_priv->dev->stats.rx_dropped++;
+		}
+	}
+
+	if (deliver_to_self) {
+		bool multicast_frame;
+
+		skb_deliver = strip_hsr_tag(skb_deliver);
+		if (!skb_deliver) {
+			hsr_priv->dev->stats.rx_dropped++;
+			goto forward;
+		}
+#if !defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
+		/* We need to memmove the whole header to work around
+		 * alignment problems caused by the 6-byte HSR tag.
+		 */
+		memmove(skb_deliver->data - HSR_TAGLEN, skb_deliver->data,
+			skb_headlen(skb_deliver));
+		skb_deliver->data -= HSR_TAGLEN;
+		skb_deliver->tail -= HSR_TAGLEN;
+#endif
+		skb_deliver->dev = hsr_priv->dev;
+		hsr_addr_subst_source(hsr_priv, skb_deliver);
+		multicast_frame = (skb_deliver->pkt_type == PACKET_MULTICAST);
+		ret = netif_rx(skb_deliver);
+		if (ret == NET_RX_DROP) {
+			hsr_priv->dev->stats.rx_dropped++;
+		} else {
+			hsr_priv->dev->stats.rx_packets++;
+			hsr_priv->dev->stats.rx_bytes += skb->len;
+			if (multicast_frame)
+				hsr_priv->dev->stats.multicast++;
+		}
+	}
+
+forward:
+	if (other_slave) {
+		skb_push(skb, ETH_HLEN);
+		skb->dev = other_slave;
+		dev_queue_xmit(skb);
+	}
+
+	return NET_RX_SUCCESS;
+}
+
+
+static struct packet_type hsr_pt __read_mostly = {
+	.type = htons(ETH_P_PRP),
+	.func = hsr_rcv,
+};
+
+static struct notifier_block hsr_nb = {
+	.notifier_call = hsr_netdev_notify,	/* Slave event notifications */
+};
+
+
+static int __init hsr_init(void)
+{
+	int res;
+
+	BUILD_BUG_ON(sizeof(struct hsr_tag) != HSR_TAGLEN);
+
+	dev_add_pack(&hsr_pt);
+
+	init_timer(&prune_timer);
+	prune_timer.function = prune_nodes_all;
+	prune_timer.data = 0;
+	prune_timer.expires = jiffies + msecs_to_jiffies(PRUNE_PERIOD);
+	add_timer(&prune_timer);
+
+	register_netdevice_notifier(&hsr_nb);
+
+	res = hsr_netlink_init();
+
+	return res;
+}
+
+static void __exit hsr_exit(void)
+{
+	unregister_netdevice_notifier(&hsr_nb);
+	del_timer(&prune_timer);
+	hsr_netlink_exit();
+	dev_remove_pack(&hsr_pt);
+}
+
+module_init(hsr_init);
+module_exit(hsr_exit);
+MODULE_LICENSE("GPL");
diff --git a/net/hsr/hsr_main.h b/net/hsr/hsr_main.h
new file mode 100644
index 0000000..c1fcfba
--- /dev/null
+++ b/net/hsr/hsr_main.h
@@ -0,0 +1,167 @@
+/*
+ * Copyright 2011-2013 Autronica Fire and Security AS
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * Author(s):
+ *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ */
+
+#ifndef _HSR_PRIVATE_H
+#define _HSR_PRIVATE_H
+
+#include <linux/netdevice.h>
+#include <linux/list.h>
+
+
+/* Time constants as specified in the HSR specification (IEC-62439-3 2010)
+ * Table 8.
+ * All values in milliseconds.
+ */
+#define HSR_LIFE_CHECK_INTERVAL		 2000 /* ms */
+#define HSR_NODE_FORGET_TIME		60000 /* ms */
+#define HSR_ANNOUNCE_INTERVAL		  100 /* ms */
+
+
+/* By how much may slave1 and slave2 timestamps of latest received frame from
+ * each node differ before we notify of communication problem?
+ */
+#define MAX_SLAVE_DIFF			 3000 /* ms */
+
+
+/* How often shall we check for broken ring and remove node entries older than
+ * HSR_NODE_FORGET_TIME?
+ */
+#define PRUNE_PERIOD			 3000 /* ms */
+
+
+#define HSR_TLV_ANNOUNCE		   22
+#define HSR_TLV_LIFE_CHECK		   23
+
+
+/* HSR Tag.
+ * As defined in IEC-62439-3:2010, the HSR tag is really { ethertype = 0x88FB,
+ * path, LSDU_size, sequence Nr }. But we let eth_header() create { h_dest,
+ * h_source, h_proto = 0x88FB }, and add { path, LSDU_size, sequence Nr,
+ * encapsulated protocol } instead.
+ */
+#define HSR_TAGLEN	6
+
+/* Field names below as defined in the IEC:2010 standard for HSR. */
+struct hsr_tag {
+	__be16		path_and_LSDU_size;
+	__be16		sequence_nr;
+	__be16		encap_proto;
+} __packed;
+
+
+/* The helper functions below assumes that 'path' occupies the 4 most
+ * significant bits of the 16-bit field shared by 'path' and 'LSDU_size' (or
+ * equivalently, the 4 most significant bits of HSR tag byte 14).
+ *
+ * This is unclear in the IEC specification; its definition of MAC addresses
+ * indicates the spec is written with the least significant bit first (to the
+ * left). This, however, would mean that the LSDU field would be split in two
+ * with the path field in-between, which seems strange. I'm guessing the MAC
+ * address definition is in error.
+ */
+static inline u16 get_hsr_tag_path(struct hsr_tag *ht)
+{
+	return ntohs(ht->path_and_LSDU_size) >> 12;
+}
+
+static inline u16 get_hsr_tag_LSDU_size(struct hsr_tag *ht)
+{
+	return ntohs(ht->path_and_LSDU_size) & 0x0FFF;
+}
+
+static inline void set_hsr_tag_path(struct hsr_tag *ht, u16 path)
+{
+	ht->path_and_LSDU_size = htons(
+			(ntohs(ht->path_and_LSDU_size) & 0x0FFF) | (path << 12));
+}
+
+static inline void set_hsr_tag_LSDU_size(struct hsr_tag *ht, u16 LSDU_size)
+{
+	ht->path_and_LSDU_size = htons(
+			(ntohs(ht->path_and_LSDU_size) & 0xF000) |
+			(LSDU_size & 0x0FFF));
+}
+
+struct hsr_ethhdr {
+	struct ethhdr	ethhdr;
+	struct hsr_tag	hsr_tag;
+} __packed;
+
+
+/* HSR Supervision Frame data types.
+ * Field names as defined in the IEC:2010 standard for HSR.
+ */
+struct hsr_sup_tag {
+	__be16		path_and_HSR_Ver;
+	__be16		sequence_nr;
+	__u8		HSR_TLV_Type;
+	__u8		HSR_TLV_Length;
+} __packed;
+
+struct hsr_sup_payload {
+	unsigned char	MacAddressA[ETH_ALEN];
+} __packed;
+
+static inline u16 get_hsr_stag_path(struct hsr_sup_tag *hst)
+{
+	return get_hsr_tag_path((struct hsr_tag *) hst);
+}
+
+static inline u16 get_hsr_stag_HSR_ver(struct hsr_sup_tag *hst)
+{
+	return get_hsr_tag_LSDU_size((struct hsr_tag *) hst);
+}
+
+static inline void set_hsr_stag_path(struct hsr_sup_tag *hst, u16 path)
+{
+	set_hsr_tag_path((struct hsr_tag *) hst, path);
+}
+
+static inline void set_hsr_stag_HSR_Ver(struct hsr_sup_tag *hst, u16 HSR_Ver)
+{
+	set_hsr_tag_LSDU_size((struct hsr_tag *) hst, HSR_Ver);
+}
+
+struct hsr_ethhdr_sp {
+	struct ethhdr		ethhdr;
+	struct hsr_sup_tag	hsr_sup;
+} __packed;
+
+
+enum hsr_dev_idx {
+	HSR_DEV_NONE = -1,
+	HSR_DEV_SLAVE_A = 0,
+	HSR_DEV_SLAVE_B,
+	HSR_DEV_MASTER,
+};
+#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	node_db;	/* Other HSR nodes */
+	struct list_head	self_node_db;	/* MACs of slaves */
+	struct timer_list	announce_timer;	/* Supervision frame dispatch */
+	int announce_count;
+	u16 sequence_nr;
+	spinlock_t seqnr_lock;			/* locking for sequence_nr */
+	unsigned char		sup_multicast_addr[ETH_ALEN];
+};
+
+void register_hsr_master(struct hsr_priv *hsr_priv);
+void unregister_hsr_master(struct hsr_priv *hsr_priv);
+bool is_hsr_slave(struct net_device *dev);
+
+#endif /*  _HSR_PRIVATE_H */
diff --git a/net/hsr/hsr_netlink.c b/net/hsr/hsr_netlink.c
new file mode 100644
index 0000000..7ac0392
--- /dev/null
+++ b/net/hsr/hsr_netlink.c
@@ -0,0 +1,458 @@
+/*
+ * Copyright 2011-2013 Autronica Fire and Security AS
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * Author(s):
+ *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ *
+ * Routines for handling Netlink messages for HSR.
+ */
+
+#include "hsr_netlink.h"
+#include <linux/kernel.h>
+#include <net/rtnetlink.h>
+#include <net/genetlink.h>
+#include "hsr_main.h"
+#include "hsr_device.h"
+#include "hsr_framereg.h"
+
+static const struct nla_policy hsr_policy[IFLA_HSR_MAX + 1] = {
+	[IFLA_HSR_SLAVE1]		= { .type = NLA_U32 },
+	[IFLA_HSR_SLAVE2]		= { .type = NLA_U32 },
+	[IFLA_HSR_MULTICAST_SPEC]	= { .type = NLA_U8 },
+};
+
+
+/* Here, it seems a netdevice has already been allocated for us, and the
+ * hsr_dev_setup routine has been executed. Nice!
+ */
+static int hsr_newlink(struct net *src_net, struct net_device *dev,
+		       struct nlattr *tb[], struct nlattr *data[])
+{
+	struct net_device *link[2];
+	unsigned char multicast_spec;
+
+	if (!data[IFLA_HSR_SLAVE1]) {
+		netdev_info(dev, "IFLA_HSR_SLAVE1 missing!\n");
+		return -EINVAL;
+	}
+	link[0] = __dev_get_by_index(src_net, nla_get_u32(data[IFLA_HSR_SLAVE1]));
+	if (!data[IFLA_HSR_SLAVE2]) {
+		netdev_info(dev, "IFLA_HSR_SLAVE2 missing!\n");
+		return -EINVAL;
+	}
+	link[1] = __dev_get_by_index(src_net, nla_get_u32(data[IFLA_HSR_SLAVE2]));
+
+	if (!link[0] || !link[1])
+		return -ENODEV;
+	if (link[0] == link[1])
+		return -EINVAL;
+
+	if (!data[IFLA_HSR_MULTICAST_SPEC])
+		multicast_spec = 0;
+	else
+		multicast_spec = nla_get_u8(data[IFLA_HSR_MULTICAST_SPEC]);
+
+	return hsr_dev_finalize(dev, link, multicast_spec);
+}
+
+static struct rtnl_link_ops hsr_link_ops __read_mostly = {
+	.kind		= "hsr",
+	.maxtype	= IFLA_HSR_MAX,
+	.policy		= hsr_policy,
+	.priv_size	= sizeof(struct hsr_priv),
+	.setup		= hsr_dev_setup,
+	.newlink	= hsr_newlink,
+};
+
+
+
+/* attribute policy */
+/* NLA_BINARY missing in libnl; use NLA_UNSPEC in userspace instead. */
+static const struct nla_policy hsr_genl_policy[HSR_A_MAX + 1] = {
+	[HSR_A_NODE_ADDR] = { .type = NLA_BINARY, .len = ETH_ALEN },
+	[HSR_A_NODE_ADDR_B] = { .type = NLA_BINARY, .len = ETH_ALEN },
+	[HSR_A_IFINDEX] = { .type = NLA_U32 },
+	[HSR_A_IF1_AGE] = { .type = NLA_U32 },
+	[HSR_A_IF2_AGE] = { .type = NLA_U32 },
+	[HSR_A_IF1_SEQ] = { .type = NLA_U16 },
+	[HSR_A_IF2_SEQ] = { .type = NLA_U16 },
+};
+
+static struct genl_family hsr_genl_family = {
+	.id = GENL_ID_GENERATE,
+	.hdrsize = 0,
+	.name = "HSR",
+	.version = 1,
+	.maxattr = HSR_A_MAX,
+};
+
+static struct genl_multicast_group hsr_network_genl_mcgrp = {
+	.name = "hsr-network",
+};
+
+
+
+/* This is called if for some node with MAC address addr, we only get frames
+ * over one of the slave interfaces. This would indicate an open network ring
+ * (i.e. a link has failed somewhere).
+ */
+void hsr_nl_ringerror(struct hsr_priv *hsr_priv, unsigned char addr[ETH_ALEN],
+		      enum hsr_dev_idx dev_idx)
+{
+	struct sk_buff *skb;
+	void *msg_head;
+	int res;
+	int ifindex;
+
+	skb = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
+	if (!skb)
+		goto fail;
+
+	msg_head = genlmsg_put(skb, 0, 0, &hsr_genl_family, 0, HSR_C_RING_ERROR);
+	if (!msg_head)
+		goto nla_put_failure;
+
+	res = nla_put(skb, HSR_A_NODE_ADDR, ETH_ALEN, addr);
+	if (res < 0)
+		goto nla_put_failure;
+
+	if (hsr_priv->slave[dev_idx])
+		ifindex = hsr_priv->slave[dev_idx]->ifindex;
+	else
+		ifindex = -1;
+	res = nla_put_u32(skb, HSR_A_IFINDEX, ifindex);
+	if (res < 0)
+		goto nla_put_failure;
+
+	genlmsg_end(skb, msg_head);
+	genlmsg_multicast(skb, 0, hsr_network_genl_mcgrp.id, GFP_ATOMIC);
+
+	return;
+
+nla_put_failure:
+	kfree_skb(skb);
+
+fail:
+	netdev_warn(hsr_priv->dev, "Could not send HSR ring error message\n");
+}
+
+/* This is called when we haven't heard from the node with MAC address addr for
+ * some time (just before the node is removed from the node table/list).
+ */
+void hsr_nl_nodedown(struct hsr_priv *hsr_priv, unsigned char addr[ETH_ALEN])
+{
+	struct sk_buff *skb;
+	void *msg_head;
+	int res;
+
+	skb = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
+	if (!skb)
+		goto fail;
+
+	msg_head = genlmsg_put(skb, 0, 0, &hsr_genl_family, 0, HSR_C_NODE_DOWN);
+	if (!msg_head)
+		goto nla_put_failure;
+
+
+	res = nla_put(skb, HSR_A_NODE_ADDR, ETH_ALEN, addr);
+	if (res < 0)
+		goto nla_put_failure;
+
+	genlmsg_end(skb, msg_head);
+	genlmsg_multicast(skb, 0, hsr_network_genl_mcgrp.id, GFP_ATOMIC);
+
+	return;
+
+nla_put_failure:
+	kfree_skb(skb);
+
+fail:
+	netdev_warn(hsr_priv->dev, "Could not send HSR node down\n");
+}
+
+
+/* HSR_C_GET_NODE_STATUS lets userspace query the internal HSR node table
+ * about the status of a specific node in the network, defined by its MAC
+ * address.
+ *
+ * Input: hsr ifindex, node mac address
+ * Output: hsr ifindex, node mac address (copied from request),
+ *	   age of latest frame from node over slave 1, slave 2 [ms]
+ */
+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;
+
+	/* For sending */
+	struct sk_buff *skb_out;
+	void *msg_head;
+	struct hsr_priv *hsr_priv;
+	unsigned char hsr_node_addr_b[ETH_ALEN];
+	int hsr_node_if1_age;
+	u16 hsr_node_if1_seq;
+	int hsr_node_if2_age;
+	u16 hsr_node_if2_seq;
+	int addr_b_ifindex;
+	int res;
+
+	if (!info)
+		goto invalid;
+
+	na = info->attrs[HSR_A_IFINDEX];
+	if (!na)
+		goto invalid;
+	na = info->attrs[HSR_A_NODE_ADDR];
+	if (!na)
+		goto invalid;
+
+	hsr_dev = __dev_get_by_index(genl_info_net(info),
+					nla_get_u32(info->attrs[HSR_A_IFINDEX]));
+	if (!hsr_dev)
+		goto invalid;
+	if (!is_hsr_master(hsr_dev))
+		goto invalid;
+
+
+	/* Send reply */
+
+	skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!skb_out) {
+		res = -ENOMEM;
+		goto fail;
+	}
+
+	msg_head = genlmsg_put(skb_out, NETLINK_CB(skb_in).portid,
+				info->snd_seq, &hsr_genl_family, 0,
+				HSR_C_SET_NODE_STATUS);
+	if (!msg_head) {
+		res = -ENOMEM;
+		goto nla_put_failure;
+	}
+
+	res = nla_put_u32(skb_out, HSR_A_IFINDEX, hsr_dev->ifindex);
+	if (res < 0)
+		goto nla_put_failure;
+
+	hsr_priv = netdev_priv(hsr_dev);
+	res = hsr_get_node_data(hsr_priv,
+			(unsigned char *) nla_data(info->attrs[HSR_A_NODE_ADDR]),
+			hsr_node_addr_b,
+			&addr_b_ifindex,
+			&hsr_node_if1_age,
+			&hsr_node_if1_seq,
+			&hsr_node_if2_age,
+			&hsr_node_if2_seq);
+	if (res < 0)
+		goto fail;
+
+	res = nla_put(skb_out, HSR_A_NODE_ADDR, ETH_ALEN,
+					nla_data(info->attrs[HSR_A_NODE_ADDR]));
+	if (res < 0)
+		goto nla_put_failure;
+
+	if (addr_b_ifindex > -1) {
+		res = nla_put(skb_out, HSR_A_NODE_ADDR_B, ETH_ALEN,
+								hsr_node_addr_b);
+		if (res < 0)
+			goto nla_put_failure;
+
+		res = nla_put_u32(skb_out, HSR_A_ADDR_B_IFINDEX, addr_b_ifindex);
+		if (res < 0)
+			goto nla_put_failure;
+	}
+
+	res = nla_put_u32(skb_out, HSR_A_IF1_AGE, hsr_node_if1_age);
+	if (res < 0)
+		goto nla_put_failure;
+	res = nla_put_u16(skb_out, HSR_A_IF1_SEQ, hsr_node_if1_seq);
+	if (res < 0)
+		goto nla_put_failure;
+	if (hsr_priv->slave[0])
+		res = nla_put_u32(skb_out, HSR_A_IF1_IFINDEX,
+						hsr_priv->slave[0]->ifindex);
+	if (res < 0)
+		goto nla_put_failure;
+
+	res = nla_put_u32(skb_out, HSR_A_IF2_AGE, hsr_node_if2_age);
+	if (res < 0)
+		goto nla_put_failure;
+	res = nla_put_u16(skb_out, HSR_A_IF2_SEQ, hsr_node_if2_seq);
+	if (res < 0)
+		goto nla_put_failure;
+	if (hsr_priv->slave[1])
+		res = nla_put_u32(skb_out, HSR_A_IF2_IFINDEX,
+						hsr_priv->slave[1]->ifindex);
+
+	genlmsg_end(skb_out, msg_head);
+	genlmsg_unicast(genl_info_net(info), skb_out, info->snd_portid);
+
+	return 0;
+
+invalid:
+	netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL);
+	return 0;
+
+nla_put_failure:
+	kfree_skb(skb_out);
+	/* Fall through */
+
+fail:
+	return res;
+}
+
+static struct genl_ops hsr_ops_get_node_status = {
+	.cmd = HSR_C_GET_NODE_STATUS,
+	.flags = 0,
+	.policy = hsr_genl_policy,
+	.doit = hsr_get_node_status,
+	.dumpit = NULL,
+};
+
+
+/* Get a list of MacAddressA of all nodes known to this node (other than self).
+ */
+static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
+{
+	/* For receiving */
+	struct nlattr *na;
+	struct net_device *hsr_dev;
+
+	/* For sending */
+	struct sk_buff *skb_out;
+	void *msg_head;
+	struct hsr_priv *hsr_priv;
+	void *pos;
+	unsigned char addr[ETH_ALEN];
+	int res;
+
+	if (!info)
+		goto invalid;
+
+	na = info->attrs[HSR_A_IFINDEX];
+	if (!na)
+		goto invalid;
+
+	hsr_dev = __dev_get_by_index(genl_info_net(info),
+				     nla_get_u32(info->attrs[HSR_A_IFINDEX]));
+	if (!hsr_dev)
+		goto invalid;
+	if (!is_hsr_master(hsr_dev))
+		goto invalid;
+
+
+	/* Send reply */
+
+	skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!skb_out) {
+		res = -ENOMEM;
+		goto fail;
+	}
+
+	msg_head = genlmsg_put(skb_out, NETLINK_CB(skb_in).portid,
+				info->snd_seq, &hsr_genl_family, 0,
+				HSR_C_SET_NODE_LIST);
+	if (!msg_head) {
+		res = -ENOMEM;
+		goto nla_put_failure;
+	}
+
+	res = nla_put_u32(skb_out, HSR_A_IFINDEX, hsr_dev->ifindex);
+	if (res < 0)
+		goto nla_put_failure;
+
+	hsr_priv = netdev_priv(hsr_dev);
+
+	rcu_read_lock();
+	pos = hsr_get_next_node(hsr_priv, NULL, addr);
+	while (pos) {
+		res = nla_put(skb_out, HSR_A_NODE_ADDR, ETH_ALEN, addr);
+		if (res < 0) {
+			rcu_read_unlock();
+			goto nla_put_failure;
+		}
+		pos = hsr_get_next_node(hsr_priv, pos, addr);
+	}
+	rcu_read_unlock();
+
+	genlmsg_end(skb_out, msg_head);
+	genlmsg_unicast(genl_info_net(info), skb_out, info->snd_portid);
+
+	return 0;
+
+invalid:
+	netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL);
+	return 0;
+
+nla_put_failure:
+	kfree_skb(skb_out);
+	/* Fall through */
+
+fail:
+	return res;
+}
+
+
+static struct genl_ops hsr_ops_get_node_list = {
+	.cmd = HSR_C_GET_NODE_LIST,
+	.flags = 0,
+	.policy = hsr_genl_policy,
+	.doit = hsr_get_node_list,
+	.dumpit = NULL,
+};
+
+int __init hsr_netlink_init(void)
+{
+	int rc;
+
+	rc = rtnl_link_register(&hsr_link_ops);
+	if (rc)
+		goto fail_rtnl_link_register;
+
+	rc = genl_register_family(&hsr_genl_family);
+	if (rc)
+		goto fail_genl_register_family;
+
+	rc = genl_register_ops(&hsr_genl_family, &hsr_ops_get_node_status);
+	if (rc)
+		goto fail_genl_register_ops;
+
+	rc = genl_register_ops(&hsr_genl_family, &hsr_ops_get_node_list);
+	if (rc)
+		goto fail_genl_register_ops_node_list;
+
+	rc = genl_register_mc_group(&hsr_genl_family, &hsr_network_genl_mcgrp);
+	if (rc)
+		goto fail_genl_register_mc_group;
+
+	return 0;
+
+fail_genl_register_mc_group:
+	genl_unregister_ops(&hsr_genl_family, &hsr_ops_get_node_list);
+fail_genl_register_ops_node_list:
+	genl_unregister_ops(&hsr_genl_family, &hsr_ops_get_node_status);
+fail_genl_register_ops:
+	genl_unregister_family(&hsr_genl_family);
+fail_genl_register_family:
+	rtnl_link_unregister(&hsr_link_ops);
+fail_rtnl_link_register:
+
+	return rc;
+}
+
+void __exit hsr_netlink_exit(void)
+{
+	genl_unregister_mc_group(&hsr_genl_family, &hsr_network_genl_mcgrp);
+	genl_unregister_ops(&hsr_genl_family, &hsr_ops_get_node_status);
+	genl_unregister_family(&hsr_genl_family);
+
+	rtnl_link_unregister(&hsr_link_ops);
+}
+
+MODULE_ALIAS_RTNL_LINK("hsr");
diff --git a/net/hsr/hsr_netlink.h b/net/hsr/hsr_netlink.h
new file mode 100644
index 0000000..4f1d6ee
--- /dev/null
+++ b/net/hsr/hsr_netlink.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright 2011-2013 Autronica Fire and Security AS
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * Author(s):
+ *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ */
+
+#ifndef __HSR_NETLINK_H
+#define __HSR_NETLINK_H
+
+#include <linux/if_ether.h>
+#include <linux/module.h>
+#include <uapi/linux/hsr_netlink.h>
+
+struct hsr_priv;
+
+int __init hsr_netlink_init(void);
+void __exit hsr_netlink_exit(void);
+
+void hsr_nl_ringerror(struct hsr_priv *hsr_priv, unsigned char addr[ETH_ALEN],
+		      int dev_idx);
+void hsr_nl_nodedown(struct hsr_priv *hsr_priv, unsigned char addr[ETH_ALEN]);
+void hsr_nl_framedrop(int dropcount, int dev_idx);
+void hsr_nl_linkdown(int dev_idx);
+
+#endif /* __HSR_NETLINK_H */
