Merge branch 'hsr-next'

Arvid Brodin says:

====================
net/hsr: Use list_head+rcu, better frame dispatch, etc.

This patch series is meant to improve the HSR code in several ways:

* Better code readability.
* In general, make the code structure more like the net/bridge code (HSR
  operates similarly to a bridge, but uses the HSR-specific frame headers to
  break up rings, instead of the STP protocol).
* Better handling of HSR ports' net_device features.
* Use list_head and the _rcu list traversing routines instead of array of slave
  devices.
* Make it easy to support HSR Interlink devices (for future Redbox/Quadbox
  support).
* Somewhat better throughput on non-HAVE_EFFICIENT_UNALIGNED_ACCESS archs, due
  to lesser copying of skb data.

The code has been tested in a ring together with other HSR nodes running
unchanged code, on both avr32 and x86_64. There should only be one minor change
in behaviour from a user perspective:

* Anyone using the Netlink HSR_C_GET_NODE_LIST message to dump the internal
  node database will notice that the database now also contains the self node.

All patches pass 'checkpatch.pl --ignore CAMELCASE --max-line-length=83
--strict' with only CHECKs, each of which have been deliberately left in place.

The final code passes sparse checks with no output.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/hsr/Makefile

@@ -4,4 +4,5 @@
 
 obj-$(CONFIG_HSR)	+= hsr.o
 
-hsr-y			:= hsr_main.o hsr_framereg.o hsr_device.o hsr_netlink.o
+hsr-y			:= hsr_main.o hsr_framereg.o hsr_device.o \
+			   hsr_netlink.o hsr_slave.o hsr_forward.o

net/hsr/hsr_device.h

-/* Copyright 2011-2013 Autronica Fire and Security AS
+/* Copyright 2011-2014 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
@@ -6,7 +6,7 @@
  * any later version.
  *
  * Author(s):
- *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
  */
 
 #ifndef __HSR_DEVICE_H
@@ -18,12 +18,8 @@
 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);
+void hsr_check_carrier_and_operstate(struct hsr_priv *hsr);
 bool is_hsr_master(struct net_device *dev);
-int hsr_get_max_mtu(struct hsr_priv *hsr_priv);
+int hsr_get_max_mtu(struct hsr_priv *hsr);
 
 #endif /* __HSR_DEVICE_H */

net/hsr/hsr_forward.h

+/* Copyright 2011-2014 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):
+ *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
+ */
+
+#ifndef __HSR_FORWARD_H
+#define __HSR_FORWARD_H
+
+#include <linux/netdevice.h>
+#include "hsr_main.h"
+
+void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port);
+
+#endif /* __HSR_FORWARD_H */

net/hsr/hsr_framereg.h

-/* Copyright 2011-2013 Autronica Fire and Security AS
+/* Copyright 2011-2014 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
@@ -6,42 +6,43 @@
  * any later version.
  *
  * Author(s):
- *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
  */
 
-#ifndef _HSR_FRAMEREG_H
-#define _HSR_FRAMEREG_H
+#ifndef __HSR_FRAMEREG_H
+#define __HSR_FRAMEREG_H
 
 #include "hsr_main.h"
 
-struct node_entry;
+struct hsr_node;
 
-struct node_entry *hsr_find_node(struct list_head *node_db, struct sk_buff *skb);
+struct hsr_node *hsr_add_node(struct list_head *node_db, unsigned char addr[],
+			      u16 seq_out);
+struct hsr_node *hsr_get_node(struct list_head *node_db, struct sk_buff *skb,
+			      bool is_sup);
+void hsr_handle_sup_frame(struct sk_buff *skb, struct hsr_node *node_curr,
+			  struct hsr_port *port);
+bool hsr_addr_is_self(struct hsr_priv *hsr, unsigned char *addr);
 
-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_node *node, struct sk_buff *skb);
+void hsr_addr_subst_dest(struct hsr_node *node_src, struct sk_buff *skb,
+			 struct hsr_port *port);
 
-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 hsr_node *node, struct hsr_port *port,
+			   u16 sequence_nr);
+int hsr_register_frame_out(struct hsr_port *port, struct hsr_node *node,
+			   u16 sequence_nr);
 
-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);
+void hsr_prune_nodes(unsigned long data);
 
 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,
+void *hsr_get_next_node(struct hsr_priv *hsr, void *_pos,
 			unsigned char addr[ETH_ALEN]);
 
-int hsr_get_node_data(struct hsr_priv *hsr_priv,
+int hsr_get_node_data(struct hsr_priv *hsr,
 		      const unsigned char *addr,
 		      unsigned char addr_b[ETH_ALEN],
 		      unsigned int *addr_b_ifindex,
@@ -50,4 +51,4 @@ int hsr_get_node_data(struct hsr_priv *hsr_priv,
 		      int *if2_age,
 		      u16 *if2_seq);
 
-#endif /* _HSR_FRAMEREG_H */
+#endif /* __HSR_FRAMEREG_H */

net/hsr/hsr_main.h

-/* Copyright 2011-2013 Autronica Fire and Security AS
+/* Copyright 2011-2014 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
@@ -6,11 +6,11 @@
  * any later version.
  *
  * Author(s):
- *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
  */
 
-#ifndef _HSR_PRIVATE_H
-#define _HSR_PRIVATE_H
+#ifndef __HSR_PRIVATE_H
+#define __HSR_PRIVATE_H
 
 #include <linux/netdevice.h>
 #include <linux/list.h>
@@ -29,6 +29,7 @@
  * each node differ before we notify of communication problem?
  */
 #define MAX_SLAVE_DIFF			 3000 /* ms */
+#define HSR_SEQNR_START			(USHRT_MAX - 1024)
 
 
 /* How often shall we check for broken ring and remove node entries older than
@@ -46,16 +47,16 @@
  * 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.
+ *
+ * Field names as defined in the IEC:2010 standard for HSR.
  */
-#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;
 
+#define HSR_HLEN	6
 
 /* 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
@@ -136,31 +137,47 @@ 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	node_db;	/* Other HSR nodes */
+	struct list_head	ports;
+	struct list_head	node_db;	/* Known HSR nodes */
 	struct list_head	self_node_db;	/* MACs of slaves */
 	struct timer_list	announce_timer;	/* Supervision frame dispatch */
+	struct timer_list	prune_timer;
 	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);
+#define hsr_for_each_port(hsr, port) \
+	list_for_each_entry_rcu((port), &(hsr)->ports, port_list)
+
+struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt);
+
+/* Caller must ensure skb is a valid HSR frame */
+static inline u16 hsr_get_skb_sequence_nr(struct sk_buff *skb)
+{
+	struct hsr_ethhdr *hsr_ethhdr;
+
+	hsr_ethhdr = (struct hsr_ethhdr *) skb_mac_header(skb);
+	return ntohs(hsr_ethhdr->hsr_tag.sequence_nr);
+}
 
-#endif /*  _HSR_PRIVATE_H */
+#endif /*  __HSR_PRIVATE_H */

net/hsr/hsr_netlink.c

-/* Copyright 2011-2013 Autronica Fire and Security AS
+/* Copyright 2011-2014 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
@@ -6,7 +6,7 @@
  * any later version.
  *
  * Author(s):
- *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
  *
  * Routines for handling Netlink messages for HSR.
  */
@@ -37,13 +37,17 @@ static int hsr_newlink(struct net *src_net, struct net_device *dev,
 	struct net_device *link[2];
 	unsigned char multicast_spec;
 
+	if (!data) {
+		netdev_info(dev, "HSR: No slave devices specified\n");
+		return -EINVAL;
+	}
 	if (!data[IFLA_HSR_SLAVE1]) {
-		netdev_info(dev, "IFLA_HSR_SLAVE1 missing!\n");
+		netdev_info(dev, "HSR: Slave1 device not specified\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");
+		netdev_info(dev, "HSR: Slave2 device not specified\n");
 		return -EINVAL;
 	}
 	link[1] = __dev_get_by_index(src_net, nla_get_u32(data[IFLA_HSR_SLAVE2]));
@@ -63,21 +67,33 @@ 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_priv;
+	struct hsr_priv *hsr;
+	struct hsr_port *port;
+	int res;
 
-	hsr_priv = netdev_priv(dev);
+	hsr = netdev_priv(dev);
 
-	if (hsr_priv->slave[0])
-		if (nla_put_u32(skb, IFLA_HSR_SLAVE1, hsr_priv->slave[0]->ifindex))
-			goto nla_put_failure;
+	res = 0;
 
-	if (hsr_priv->slave[1])
-		if (nla_put_u32(skb, IFLA_HSR_SLAVE2, hsr_priv->slave[1]->ifindex))
-			goto nla_put_failure;
+	rcu_read_lock();
+	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();
+	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;
 
 	if (nla_put(skb, IFLA_HSR_SUPERVISION_ADDR, ETH_ALEN,
-		    hsr_priv->sup_multicast_addr) ||
-	    nla_put_u16(skb, IFLA_HSR_SEQ_NR, hsr_priv->sequence_nr))
+		    hsr->sup_multicast_addr) ||
+	    nla_put_u16(skb, IFLA_HSR_SEQ_NR, hsr->sequence_nr))
 		goto nla_put_failure;
 
 	return 0;
@@ -128,13 +144,13 @@ static const struct genl_multicast_group hsr_mcgrps[] = {
  * 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)
+void hsr_nl_ringerror(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN],
+		      struct hsr_port *port)
 {
 	struct sk_buff *skb;
 	void *msg_head;
+	struct hsr_port *master;
 	int res;
-	int ifindex;
 
 	skb = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
 	if (!skb)
@@ -148,11 +164,7 @@ void hsr_nl_ringerror(struct hsr_priv *hsr_priv, unsigned char addr[ETH_ALEN],
 	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);
+	res = nla_put_u32(skb, HSR_A_IFINDEX, port->dev->ifindex);
 	if (res < 0)
 		goto nla_put_failure;
 
@@ -165,16 +177,20 @@ void hsr_nl_ringerror(struct hsr_priv *hsr_priv, unsigned char addr[ETH_ALEN],
 	kfree_skb(skb);
 
 fail:
-	netdev_warn(hsr_priv->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
  * 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])
+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);
@@ -199,7 +215,10 @@ void hsr_nl_nodedown(struct hsr_priv *hsr_priv, unsigned char addr[ETH_ALEN])
 	kfree_skb(skb);
 
 fail:
-	netdev_warn(hsr_priv->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();
 }
 
 
@@ -220,7 +239,8 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
 	/* For sending */
 	struct sk_buff *skb_out;
 	void *msg_head;
-	struct hsr_priv *hsr_priv;
+	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;
@@ -267,8 +287,8 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
 	if (res < 0)
 		goto nla_put_failure;
 
-	hsr_priv = netdev_priv(hsr_dev);
-	res = hsr_get_node_data(hsr_priv,
+	hsr = netdev_priv(hsr_dev);
+	res = hsr_get_node_data(hsr,
 			(unsigned char *) nla_data(info->attrs[HSR_A_NODE_ADDR]),
 			hsr_node_addr_b,
 			&addr_b_ifindex,
@@ -301,9 +321,12 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
 	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])
+	rcu_read_lock();
+	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
+	if (port)
 		res = nla_put_u32(skb_out, HSR_A_IF1_IFINDEX,
-						hsr_priv->slave[0]->ifindex);
+				  port->dev->ifindex);
+	rcu_read_unlock();
 	if (res < 0)
 		goto nla_put_failure;
 
@@ -313,9 +336,14 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
 	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])
+	rcu_read_lock();
+	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
+	if (port)
 		res = nla_put_u32(skb_out, HSR_A_IF2_IFINDEX,
-						hsr_priv->slave[1]->ifindex);
+				  port->dev->ifindex);
+	rcu_read_unlock();
+	if (res < 0)
+		goto nla_put_failure;
 
 	genlmsg_end(skb_out, msg_head);
 	genlmsg_unicast(genl_info_net(info), skb_out, info->snd_portid);
@@ -334,7 +362,7 @@ static int hsr_get_node_status(struct sk_buff *skb_in, struct genl_info *info)
 	return res;
 }
 
-/* Get a list of MacAddressA of all nodes known to this node (other than self).
+/* Get a list of MacAddressA of all nodes known to this node (including self).
  */
 static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
 {
@@ -345,7 +373,7 @@ static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
 	/* For sending */
 	struct sk_buff *skb_out;
 	void *msg_head;
-	struct hsr_priv *hsr_priv;
+	struct hsr_priv *hsr;
 	void *pos;
 	unsigned char addr[ETH_ALEN];
 	int res;
@@ -385,17 +413,17 @@ static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
 	if (res < 0)
 		goto nla_put_failure;
 
-	hsr_priv = netdev_priv(hsr_dev);
+	hsr = netdev_priv(hsr_dev);
 
 	rcu_read_lock();
-	pos = hsr_get_next_node(hsr_priv, NULL, addr);
+	pos = hsr_get_next_node(hsr, 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);
+		pos = hsr_get_next_node(hsr, pos, addr);
 	}
 	rcu_read_unlock();
 

net/hsr/hsr_netlink.h

-/* Copyright 2011-2013 Autronica Fire and Security AS
+/* Copyright 2011-2014 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
@@ -6,7 +6,7 @@
  * any later version.
  *
  * Author(s):
- *	2011-2013 Arvid Brodin, arvid.brodin@xdin.com
+ *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
  */
 
 #ifndef __HSR_NETLINK_H
@@ -17,13 +17,14 @@
 #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_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_ringerror(struct hsr_priv *hsr, unsigned char addr[ETH_ALEN],
+		      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

+/* Copyright 2011-2014 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):
+ *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
+ */
+
+#include "hsr_slave.h"
+#include <linux/etherdevice.h>
+#include <linux/if_arp.h>
+#include "hsr_main.h"
+#include "hsr_device.h"
+#include "hsr_forward.h"
+#include "hsr_framereg.h"
+
+
+static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
+{
+	struct sk_buff *skb = *pskb;
+	struct hsr_port *port;
+
+	if (!skb_mac_header_was_set(skb)) {
+		WARN_ONCE(1, "%s: skb invalid", __func__);
+		return RX_HANDLER_PASS;
+	}
+
+	rcu_read_lock(); /* hsr->node_db, hsr->ports */
+	port = hsr_port_get_rcu(skb->dev);
+
+	if (hsr_addr_is_self(port->hsr, eth_hdr(skb)->h_source)) {
+		/* Directly kill frames sent by ourselves */
+		kfree_skb(skb);
+		goto finish_consume;
+	}
+
+	if (eth_hdr(skb)->h_proto != htons(ETH_P_PRP))
+		goto finish_pass;
+
+	skb_push(skb, ETH_HLEN);
+
+	hsr_forward_skb(skb, port);
+
+finish_consume:
+	rcu_read_unlock(); /* hsr->node_db, hsr->ports */
+	return RX_HANDLER_CONSUMED;
+
+finish_pass:
+	rcu_read_unlock(); /* hsr->node_db, hsr->ports */
+	return RX_HANDLER_PASS;
+}
+
+bool hsr_port_exists(const struct net_device *dev)
+{
+	return rcu_access_pointer(dev->rx_handler) == hsr_handle_frame;
+}
+
+
+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) ||
+	    (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 (hsr_port_exists(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;
+	}
+
+	if (dev->priv_flags & IFF_DONT_BRIDGE) {
+		netdev_info(dev, "This device does not support bridging.\n");
+		return -EOPNOTSUPP;
+	}
+
+	/* HSR over bonded devices has not been tested, but I'm not sure it
+	 * won't work...
+	 */
+
+	return 0;
+}
+
+
+/* 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 = dev_set_promiscuity(dev, 1);
+	if (res)
+		goto fail_promiscuity;
+
+	/* FIXME:
+	 * What does net device "adjacency" mean? Should we do
+	 * res = netdev_master_upper_dev_link(port->dev, port->hsr->dev); ?
+	 */
+
+	res = netdev_rx_handler_register(dev, hsr_handle_frame, port);
+	if (res)
+		goto fail_rx_handler;
+	dev_disable_lro(dev);
+
+	return 0;
+
+fail_rx_handler:
+	dev_set_promiscuity(dev, -1);
+fail_promiscuity:
+	dev_put(dev);
+
+	return res;
+}
+
+int hsr_add_port(struct hsr_priv *hsr, struct net_device *dev,
+		 enum hsr_port_type type)
+{
+	struct hsr_port *port, *master;
+	int res;
+
+	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);
+	netdev_update_features(master->dev);
+	dev_set_mtu(master->dev, hsr_get_max_mtu(hsr));
+
+	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) {
+		netdev_update_features(master->dev);
+		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(port->dev);
+}

net/hsr/hsr_slave.h

+/* Copyright 2011-2014 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):
+ *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
+ */
+
+#ifndef __HSR_SLAVE_H
+#define __HSR_SLAVE_H
+
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/rtnetlink.h>
+#include "hsr_main.h"
+
+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);
+bool hsr_port_exists(const struct net_device *dev);
+
+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 */