net/hsr/hsr_forward.c - kernel/msm-4.9 - Gitiles

 /* 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_forward.h"
 #include <linux/types.h>
 #include <linux/skbuff.h>
 #include <linux/etherdevice.h>
 #include <linux/if_vlan.h>
 #include "hsr_main.h"
 #include "hsr_framereg.h"


 struct hsr_node;

 struct hsr_frame_info {
 	struct sk_buff *skb_std;
 	struct sk_buff *skb_hsr;
 	struct hsr_port *port_rcv;
 	struct hsr_node *node_src;
 	u16 sequence_nr;
 	bool is_supervision;
 	bool is_vlan;
 	bool is_local_dest;
 	bool is_local_exclusive;
 };


 /* 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, struct sk_buff *skb)
 {
 	struct hsr_ethhdr_sp *hdr;

 	WARN_ON_ONCE(!skb_mac_header_was_set(skb));
 	hdr = (struct hsr_ethhdr_sp *) skb_mac_header(skb);

 	if (!ether_addr_equal(hdr->ethhdr.h_dest,
 			      hsr->sup_multicast_addr))
 		return false;

 	if (get_hsr_stag_path(&hdr->hsr_sup) != 0x0f)
 		return false;
 	if ((hdr->hsr_sup.HSR_TLV_Type != HSR_TLV_ANNOUNCE) &&
 	    (hdr->hsr_sup.HSR_TLV_Type != HSR_TLV_LIFE_CHECK))
 		return false;
 	if (hdr->hsr_sup.HSR_TLV_Length != 12)
 		return false;

 	return true;
 }


 static struct sk_buff *create_stripped_skb(struct sk_buff *skb_in,
 					   struct hsr_frame_info *frame)
 {
 	struct sk_buff *skb;
 	int copylen;
 	unsigned char *dst, *src;

 	skb_pull(skb_in, HSR_HLEN);
 	skb = __pskb_copy(skb_in, skb_headroom(skb_in) - HSR_HLEN, GFP_ATOMIC);
 	skb_push(skb_in, HSR_HLEN);
 	if (skb == NULL)
 		return NULL;

 	skb_reset_mac_header(skb);

 	if (skb->ip_summed == CHECKSUM_PARTIAL)
 		skb->csum_start -= HSR_HLEN;

 	copylen = 2*ETH_ALEN;
 	if (frame->is_vlan)
 		copylen += VLAN_HLEN;
 	src = skb_mac_header(skb_in);
 	dst = skb_mac_header(skb);
 	memcpy(dst, src, copylen);

 	skb->protocol = eth_hdr(skb)->h_proto;
 	return skb;
 }

 static struct sk_buff *frame_get_stripped_skb(struct hsr_frame_info *frame,
 					      struct hsr_port *port)
 {
 	if (!frame->skb_std)
 		frame->skb_std = create_stripped_skb(frame->skb_hsr, frame);
 	return skb_clone(frame->skb_std, GFP_ATOMIC);
 }


 static void hsr_fill_tag(struct sk_buff *skb, struct hsr_frame_info *frame,
 			 struct hsr_port *port)
 {
 	struct hsr_ethhdr *hsr_ethhdr;
 	int lane_id;
 	int lsdu_size;

 	if (port->type == HSR_PT_SLAVE_A)
 		lane_id = 0;
 	else
 		lane_id = 1;

 	lsdu_size = skb->len - 14;
 	if (frame->is_vlan)
 		lsdu_size -= 4;

 	hsr_ethhdr = (struct hsr_ethhdr *) skb_mac_header(skb);

 	set_hsr_tag_path(&hsr_ethhdr->hsr_tag, lane_id);
 	set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, lsdu_size);
 	hsr_ethhdr->hsr_tag.sequence_nr = htons(frame->sequence_nr);
 	hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
 	hsr_ethhdr->ethhdr.h_proto = htons(ETH_P_PRP);
 }

 static struct sk_buff *create_tagged_skb(struct sk_buff *skb_o,
 					 struct hsr_frame_info *frame,
 					 struct hsr_port *port)
 {
 	int movelen;
 	unsigned char *dst, *src;
 	struct sk_buff *skb;

 	/* Create the new skb with enough headroom to fit the HSR tag */
 	skb = __pskb_copy(skb_o, skb_headroom(skb_o) + HSR_HLEN, GFP_ATOMIC);
 	if (skb == NULL)
 		return NULL;
 	skb_reset_mac_header(skb);

 	if (skb->ip_summed == CHECKSUM_PARTIAL)
 		skb->csum_start += HSR_HLEN;

 	movelen = ETH_HLEN;
 	if (frame->is_vlan)
 		movelen += VLAN_HLEN;

 	src = skb_mac_header(skb);
 	dst = skb_push(skb, HSR_HLEN);
 	memmove(dst, src, movelen);
 	skb_reset_mac_header(skb);

 	hsr_fill_tag(skb, frame, port);

 	return skb;
 }

 /* If the original frame was an HSR tagged frame, just clone it to be sent
  * unchanged. Otherwise, create a private frame especially tagged for 'port'.
  */
 static struct sk_buff *frame_get_tagged_skb(struct hsr_frame_info *frame,
 					    struct hsr_port *port)
 {
 	if (frame->skb_hsr)
 		return skb_clone(frame->skb_hsr, GFP_ATOMIC);

 	if ((port->type != HSR_PT_SLAVE_A) && (port->type != HSR_PT_SLAVE_B)) {
 		WARN_ONCE(1, "HSR: Bug: trying to create a tagged frame for a non-ring port");
 		return NULL;
 	}

 	return create_tagged_skb(frame->skb_std, frame, port);
 }


 static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev,
 			       struct hsr_node *node_src)
 {
 	bool was_multicast_frame;
 	int res;

 	was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST);
 	hsr_addr_subst_source(node_src, skb);
 	skb_pull(skb, ETH_HLEN);
 	res = netif_rx(skb);
 	if (res == NET_RX_DROP) {
 		dev->stats.rx_dropped++;
 	} else {
 		dev->stats.rx_packets++;
 		dev->stats.rx_bytes += skb->len;
 		if (was_multicast_frame)
 			dev->stats.multicast++;
 	}
 }

 static int hsr_xmit(struct sk_buff *skb, struct hsr_port *port,
 		    struct hsr_frame_info *frame)
 {
 	if (frame->port_rcv->type == HSR_PT_MASTER) {
 		hsr_addr_subst_dest(frame->node_src, skb, port);

 		/* Address substitution (IEC62439-3 pp 26, 50): replace mac
 		 * address of outgoing frame with that of the outgoing slave's.
 		 */
 		ether_addr_copy(eth_hdr(skb)->h_source, port->dev->dev_addr);
 	}
 	return dev_queue_xmit(skb);
 }


 /* Forward the frame through all devices except:
  * - Back through the receiving device
  * - If it's a HSR frame: through a device where it has passed before
  * - To the local HSR master only if the frame is directly addressed to it, or
  *   a non-supervision multicast or broadcast frame.
  *
  * HSR slave devices should insert a HSR tag into the frame, or forward the
  * frame unchanged if it's already tagged. Interlink devices should strip HSR
  * tags if they're of the non-HSR type (but only after duplicate discard). The
  * master device always strips HSR tags.
  */
 static void hsr_forward_do(struct hsr_frame_info *frame)
 {
 	struct hsr_port *port;
 	struct sk_buff *skb;

 	hsr_for_each_port(frame->port_rcv->hsr, port) {
 		/* Don't send frame back the way it came */
 		if (port == frame->port_rcv)
 			continue;

 		/* Don't deliver locally unless we should */
 		if ((port->type == HSR_PT_MASTER) && !frame->is_local_dest)
 			continue;

 		/* Deliver frames directly addressed to us to master only */
 		if ((port->type != HSR_PT_MASTER) && frame->is_local_exclusive)
 			continue;

 		/* Don't send frame over port where it has been sent before */
 		if (hsr_register_frame_out(port, frame->node_src,
 					   frame->sequence_nr))
 			continue;

 		if (frame->is_supervision && (port->type == HSR_PT_MASTER)) {
 			hsr_handle_sup_frame(frame->skb_hsr,
 					     frame->node_src,
 					     frame->port_rcv);
 			continue;
 		}

 		if (port->type != HSR_PT_MASTER)
 			skb = frame_get_tagged_skb(frame, port);
 		else
 			skb = frame_get_stripped_skb(frame, port);
 		if (skb == NULL) {
 			/* FIXME: Record the dropped frame? */
 			continue;
 		}

 		skb->dev = port->dev;
 		if (port->type == HSR_PT_MASTER)
 			hsr_deliver_master(skb, port->dev, frame->node_src);
 		else
 			hsr_xmit(skb, port, frame);
 	}
 }


 static void check_local_dest(struct hsr_priv *hsr, struct sk_buff *skb,
 			     struct hsr_frame_info *frame)
 {
 	struct net_device *master_dev;

 	master_dev = hsr_port_get_hsr(hsr, HSR_PT_MASTER)->dev;

 	if (hsr_addr_is_self(hsr, eth_hdr(skb)->h_dest)) {
 		frame->is_local_exclusive = true;
 		skb->pkt_type = PACKET_HOST;
 	} else {
 		frame->is_local_exclusive = false;
 	}

 	if ((skb->pkt_type == PACKET_HOST) ||
 	    (skb->pkt_type == PACKET_MULTICAST) ||
 	    (skb->pkt_type == PACKET_BROADCAST)) {
 		frame->is_local_dest = true;
 	} else {
 		frame->is_local_dest = false;
 	}
 }


 static int hsr_fill_frame_info(struct hsr_frame_info *frame,
 			       struct sk_buff *skb, struct hsr_port *port)
 {
 	struct ethhdr *ethhdr;
 	unsigned long irqflags;

 	frame->is_supervision = is_supervision_frame(port->hsr, skb);
 	frame->node_src = hsr_get_node(&port->hsr->node_db, skb,
 				       frame->is_supervision);
 	if (frame->node_src == NULL)
 		return -1; /* Unknown node and !is_supervision, or no mem */

 	ethhdr = (struct ethhdr *) skb_mac_header(skb);
 	frame->is_vlan = false;
 	if (ethhdr->h_proto == htons(ETH_P_8021Q)) {
 		frame->is_vlan = true;
 		/* FIXME: */
 		WARN_ONCE(1, "HSR: VLAN not yet supported");
 	}
 	if (ethhdr->h_proto == htons(ETH_P_PRP)) {
 		frame->skb_std = NULL;
 		frame->skb_hsr = skb;
 		frame->sequence_nr = hsr_get_skb_sequence_nr(skb);
 	} else {
 		frame->skb_std = skb;
 		frame->skb_hsr = NULL;
 		/* Sequence nr for the master node */
 		spin_lock_irqsave(&port->hsr->seqnr_lock, irqflags);
 		frame->sequence_nr = port->hsr->sequence_nr;
 		port->hsr->sequence_nr++;
 		spin_unlock_irqrestore(&port->hsr->seqnr_lock, irqflags);
 	}

 	frame->port_rcv = port;
 	check_local_dest(port->hsr, skb, frame);

 	return 0;
 }

 /* Must be called holding rcu read lock (because of the port parameter) */
 void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port)
 {
 	struct hsr_frame_info frame;

 	if (skb_mac_header(skb) != skb->data) {
 		WARN_ONCE(1, "%s:%d: Malformed frame (port_src %s)\n",
 			  __FILE__, __LINE__, port->dev->name);
 		goto out_drop;
 	}

 	if (hsr_fill_frame_info(&frame, skb, port) < 0)
 		goto out_drop;
 	hsr_register_frame_in(frame.node_src, port, frame.sequence_nr);
 	hsr_forward_do(&frame);

 	if (frame.skb_hsr != NULL)
 		kfree_skb(frame.skb_hsr);
 	if (frame.skb_std != NULL)
 		kfree_skb(frame.skb_std);
 	return;

 out_drop:
 	port->dev->stats.tx_dropped++;
 	kfree_skb(skb);
 }
	/* 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_forward.h"
	#include <linux/types.h>
	#include <linux/skbuff.h>
	#include <linux/etherdevice.h>
	#include <linux/if_vlan.h>
	#include "hsr_main.h"
	#include "hsr_framereg.h"


	struct hsr_node;

	struct hsr_frame_info {
	struct sk_buff *skb_std;
	struct sk_buff *skb_hsr;
	struct hsr_port *port_rcv;
	struct hsr_node *node_src;
	u16 sequence_nr;
	bool is_supervision;
	bool is_vlan;
	bool is_local_dest;
	bool is_local_exclusive;
	};


	/* 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, struct sk_buff skb)
	{
	struct hsr_ethhdr_sp *hdr;

	WARN_ON_ONCE(!skb_mac_header_was_set(skb));
	hdr = (struct hsr_ethhdr_sp *) skb_mac_header(skb);

	if (!ether_addr_equal(hdr->ethhdr.h_dest,
	hsr->sup_multicast_addr))
	return false;

	if (get_hsr_stag_path(&hdr->hsr_sup) != 0x0f)
	return false;
	if ((hdr->hsr_sup.HSR_TLV_Type != HSR_TLV_ANNOUNCE) &&
	(hdr->hsr_sup.HSR_TLV_Type != HSR_TLV_LIFE_CHECK))
	return false;
	if (hdr->hsr_sup.HSR_TLV_Length != 12)
	return false;

	return true;
	}


	static struct sk_buff create_stripped_skb(struct sk_buff skb_in,
	struct hsr_frame_info *frame)
	{
	struct sk_buff *skb;
	int copylen;
	unsigned char dst, src;

	skb_pull(skb_in, HSR_HLEN);
	skb = __pskb_copy(skb_in, skb_headroom(skb_in) - HSR_HLEN, GFP_ATOMIC);
	skb_push(skb_in, HSR_HLEN);
	if (skb == NULL)
	return NULL;

	skb_reset_mac_header(skb);

	if (skb->ip_summed == CHECKSUM_PARTIAL)
	skb->csum_start -= HSR_HLEN;

	copylen = 2*ETH_ALEN;
	if (frame->is_vlan)
	copylen += VLAN_HLEN;
	src = skb_mac_header(skb_in);
	dst = skb_mac_header(skb);
	memcpy(dst, src, copylen);

	skb->protocol = eth_hdr(skb)->h_proto;
	return skb;
	}

	static struct sk_buff frame_get_stripped_skb(struct hsr_frame_info frame,
	struct hsr_port *port)
	{
	if (!frame->skb_std)
	frame->skb_std = create_stripped_skb(frame->skb_hsr, frame);
	return skb_clone(frame->skb_std, GFP_ATOMIC);
	}


	static void hsr_fill_tag(struct sk_buff skb, struct hsr_frame_info frame,
	struct hsr_port *port)
	{
	struct hsr_ethhdr *hsr_ethhdr;
	int lane_id;
	int lsdu_size;

	if (port->type == HSR_PT_SLAVE_A)
	lane_id = 0;
	else
	lane_id = 1;

	lsdu_size = skb->len - 14;
	if (frame->is_vlan)
	lsdu_size -= 4;

	hsr_ethhdr = (struct hsr_ethhdr *) skb_mac_header(skb);

	set_hsr_tag_path(&hsr_ethhdr->hsr_tag, lane_id);
	set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, lsdu_size);
	hsr_ethhdr->hsr_tag.sequence_nr = htons(frame->sequence_nr);
	hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto;
	hsr_ethhdr->ethhdr.h_proto = htons(ETH_P_PRP);
	}

	static struct sk_buff create_tagged_skb(struct sk_buff skb_o,
	struct hsr_frame_info *frame,
	struct hsr_port *port)
	{
	int movelen;
	unsigned char dst, src;
	struct sk_buff *skb;

	/* Create the new skb with enough headroom to fit the HSR tag */
	skb = __pskb_copy(skb_o, skb_headroom(skb_o) + HSR_HLEN, GFP_ATOMIC);
	if (skb == NULL)
	return NULL;
	skb_reset_mac_header(skb);

	if (skb->ip_summed == CHECKSUM_PARTIAL)
	skb->csum_start += HSR_HLEN;

	movelen = ETH_HLEN;
	if (frame->is_vlan)
	movelen += VLAN_HLEN;

	src = skb_mac_header(skb);
	dst = skb_push(skb, HSR_HLEN);
	memmove(dst, src, movelen);
	skb_reset_mac_header(skb);

	hsr_fill_tag(skb, frame, port);

	return skb;
	}

	/* If the original frame was an HSR tagged frame, just clone it to be sent
	* unchanged. Otherwise, create a private frame especially tagged for 'port'.
	*/
	static struct sk_buff frame_get_tagged_skb(struct hsr_frame_info frame,
	struct hsr_port *port)
	{
	if (frame->skb_hsr)
	return skb_clone(frame->skb_hsr, GFP_ATOMIC);

	if ((port->type != HSR_PT_SLAVE_A) && (port->type != HSR_PT_SLAVE_B)) {
	WARN_ONCE(1, "HSR: Bug: trying to create a tagged frame for a non-ring port");
	return NULL;
	}

	return create_tagged_skb(frame->skb_std, frame, port);
	}


	static void hsr_deliver_master(struct sk_buff skb, struct net_device dev,
	struct hsr_node *node_src)
	{
	bool was_multicast_frame;
	int res;

	was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST);
	hsr_addr_subst_source(node_src, skb);
	skb_pull(skb, ETH_HLEN);
	res = netif_rx(skb);
	if (res == NET_RX_DROP) {
	dev->stats.rx_dropped++;
	} else {
	dev->stats.rx_packets++;
	dev->stats.rx_bytes += skb->len;
	if (was_multicast_frame)
	dev->stats.multicast++;
	}
	}

	static int hsr_xmit(struct sk_buff skb, struct hsr_port port,
	struct hsr_frame_info *frame)
	{
	if (frame->port_rcv->type == HSR_PT_MASTER) {
	hsr_addr_subst_dest(frame->node_src, skb, port);

	/* Address substitution (IEC62439-3 pp 26, 50): replace mac
	* address of outgoing frame with that of the outgoing slave's.
	*/
	ether_addr_copy(eth_hdr(skb)->h_source, port->dev->dev_addr);
	}
	return dev_queue_xmit(skb);
	}


	/* Forward the frame through all devices except:
	* - Back through the receiving device
	* - If it's a HSR frame: through a device where it has passed before
	* - To the local HSR master only if the frame is directly addressed to it, or
	* a non-supervision multicast or broadcast frame.
	*
	* HSR slave devices should insert a HSR tag into the frame, or forward the
	* frame unchanged if it's already tagged. Interlink devices should strip HSR
	* tags if they're of the non-HSR type (but only after duplicate discard). The
	* master device always strips HSR tags.
	*/
	static void hsr_forward_do(struct hsr_frame_info *frame)
	{
	struct hsr_port *port;
	struct sk_buff *skb;

	hsr_for_each_port(frame->port_rcv->hsr, port) {
	/* Don't send frame back the way it came */
	if (port == frame->port_rcv)
	continue;

	/* Don't deliver locally unless we should */
	if ((port->type == HSR_PT_MASTER) && !frame->is_local_dest)
	continue;

	/* Deliver frames directly addressed to us to master only */
	if ((port->type != HSR_PT_MASTER) && frame->is_local_exclusive)
	continue;

	/* Don't send frame over port where it has been sent before */
	if (hsr_register_frame_out(port, frame->node_src,
	frame->sequence_nr))
	continue;

	if (frame->is_supervision && (port->type == HSR_PT_MASTER)) {
	hsr_handle_sup_frame(frame->skb_hsr,
	frame->node_src,
	frame->port_rcv);
	continue;
	}

	if (port->type != HSR_PT_MASTER)
	skb = frame_get_tagged_skb(frame, port);
	else
	skb = frame_get_stripped_skb(frame, port);
	if (skb == NULL) {
	/* FIXME: Record the dropped frame? */
	continue;
	}

	skb->dev = port->dev;
	if (port->type == HSR_PT_MASTER)
	hsr_deliver_master(skb, port->dev, frame->node_src);
	else
	hsr_xmit(skb, port, frame);
	}
	}


	static void check_local_dest(struct hsr_priv hsr, struct sk_buff skb,
	struct hsr_frame_info *frame)
	{
	struct net_device *master_dev;

	master_dev = hsr_port_get_hsr(hsr, HSR_PT_MASTER)->dev;

	if (hsr_addr_is_self(hsr, eth_hdr(skb)->h_dest)) {
	frame->is_local_exclusive = true;
	skb->pkt_type = PACKET_HOST;
	} else {
	frame->is_local_exclusive = false;
	}

	if ((skb->pkt_type == PACKET_HOST) \|\|
	(skb->pkt_type == PACKET_MULTICAST) \|\|
	(skb->pkt_type == PACKET_BROADCAST)) {
	frame->is_local_dest = true;
	} else {
	frame->is_local_dest = false;
	}
	}


	static int hsr_fill_frame_info(struct hsr_frame_info *frame,
	struct sk_buff skb, struct hsr_port port)
	{
	struct ethhdr *ethhdr;
	unsigned long irqflags;

	frame->is_supervision = is_supervision_frame(port->hsr, skb);
	frame->node_src = hsr_get_node(&port->hsr->node_db, skb,
	frame->is_supervision);
	if (frame->node_src == NULL)
	return -1; /* Unknown node and !is_supervision, or no mem */

	ethhdr = (struct ethhdr *) skb_mac_header(skb);
	frame->is_vlan = false;
	if (ethhdr->h_proto == htons(ETH_P_8021Q)) {
	frame->is_vlan = true;
	/* FIXME: */
	WARN_ONCE(1, "HSR: VLAN not yet supported");
	}
	if (ethhdr->h_proto == htons(ETH_P_PRP)) {
	frame->skb_std = NULL;
	frame->skb_hsr = skb;
	frame->sequence_nr = hsr_get_skb_sequence_nr(skb);
	} else {
	frame->skb_std = skb;
	frame->skb_hsr = NULL;
	/* Sequence nr for the master node */
	spin_lock_irqsave(&port->hsr->seqnr_lock, irqflags);
	frame->sequence_nr = port->hsr->sequence_nr;
	port->hsr->sequence_nr++;
	spin_unlock_irqrestore(&port->hsr->seqnr_lock, irqflags);
	}

	frame->port_rcv = port;
	check_local_dest(port->hsr, skb, frame);

	return 0;
	}

	/* Must be called holding rcu read lock (because of the port parameter) */
	void hsr_forward_skb(struct sk_buff skb, struct hsr_port port)
	{
	struct hsr_frame_info frame;

	if (skb_mac_header(skb) != skb->data) {
	WARN_ONCE(1, "%s:%d: Malformed frame (port_src %s)\n",
	__FILE__, __LINE__, port->dev->name);
	goto out_drop;
	}

	if (hsr_fill_frame_info(&frame, skb, port) < 0)
	goto out_drop;
	hsr_register_frame_in(frame.node_src, port, frame.sequence_nr);
	hsr_forward_do(&frame);

	if (frame.skb_hsr != NULL)
	kfree_skb(frame.skb_hsr);
	if (frame.skb_std != NULL)
	kfree_skb(frame.skb_std);
	return;

	out_drop:
	port->dev->stats.tx_dropped++;
	kfree_skb(skb);
	}