Merge branch 'tipc-ipoib'

Patrick McHardy says:

====================
The following patchset adds support for running TIPC over InfiniBand.
The patchset consists of three parts (+ a minor fix for the ethernet media
type):

- Preparation: removal of an the unused str2addr callback and move of the
  bcast_addr from struct tipc_media to struct tipc_bearer. This is necessary
  because InfiniBand doesn't have a fixed broadcast address like ethernet,
  so it needs to be initialized with the device's broadcast address when
  the bearer is enabled

- Introduction of a TIPC InfiniBand media type. A new media type is needed
  to deal with the different address sizes

- Support for ETH_P_TIPC in IPoIB

Since the last posting I've addressed all feedback I received and rebased
to the current net-next tree.

I consider these patches ready for merging. Since they mainly affect TIPC
code, I'd propose to have them either go through the TIPC tree or through
Dave directly (not sure how TIPC patches are managed).
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

10 files changed, 438 insertions, 42 deletions

diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c
index 8534afd..554b906 100644
--- a/drivers/infiniband/ulp/ipoib/ipoib_main.c
+++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c
@@ -730,7 +730,8 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
 		if ((header->proto != htons(ETH_P_IP)) &&
 		    (header->proto != htons(ETH_P_IPV6)) &&
 		    (header->proto != htons(ETH_P_ARP)) &&
-		    (header->proto != htons(ETH_P_RARP))) {
+		    (header->proto != htons(ETH_P_RARP)) &&
+		    (header->proto != htons(ETH_P_TIPC))) {
 			/* ethertype not supported by IPoIB */
 			++dev->stats.tx_dropped;
 			dev_kfree_skb_any(skb);
@@ -751,6 +752,7 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
 	switch (header->proto) {
 	case htons(ETH_P_IP):
 	case htons(ETH_P_IPV6):
+	case htons(ETH_P_TIPC):
 		neigh = ipoib_neigh_get(dev, cb->hwaddr);
 		if (unlikely(!neigh)) {
 			neigh_add_path(skb, cb->hwaddr, dev);
diff --git a/net/tipc/Kconfig b/net/tipc/Kconfig
index 4f99600..c890848 100644
--- a/net/tipc/Kconfig
+++ b/net/tipc/Kconfig
@@ -31,3 +31,10 @@ config TIPC_PORTS
 
 	  Setting this to a smaller value saves some memory,
 	  setting it to higher allows for more ports.
+
+config TIPC_MEDIA_IB
+	bool "InfiniBand media type support"
+	depends on TIPC && INFINIBAND_IPOIB
+	help
+	  Saying Y here will enable support for running TIPC on
+	  IP-over-InfiniBand devices.
diff --git a/net/tipc/Makefile b/net/tipc/Makefile
index 6cd55d6..4df8e02 100644
--- a/net/tipc/Makefile
+++ b/net/tipc/Makefile
@@ -9,3 +9,5 @@ tipc-y	+= addr.o bcast.o bearer.o config.o \
 	   name_distr.o  subscr.o name_table.o net.o  \
 	   netlink.o node.o node_subscr.o port.o ref.o  \
 	   socket.o log.o eth_media.o
+
+tipc-$(CONFIG_TIPC_MEDIA_IB)	+= ib_media.o
diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index 2655c9f..25e159c 100644
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -620,10 +620,10 @@ static int tipc_bcbearer_send(struct sk_buff *buf,
 			continue;	/* bearer pair doesn't add anything */
 
 		if (!tipc_bearer_blocked(p))
-			tipc_bearer_send(p, buf, &p->media->bcast_addr);
+			tipc_bearer_send(p, buf, &p->bcast_addr);
 		else if (s && !tipc_bearer_blocked(s))
 			/* unable to send on primary bearer */
-			tipc_bearer_send(s, buf, &s->media->bcast_addr);
+			tipc_bearer_send(s, buf, &s->bcast_addr);
 		else
 			/* unable to send on either bearer */
 			continue;
diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index aa62f93..cb29ef7 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -39,7 +39,7 @@
 #include "bearer.h"
 #include "discover.h"
 
-#define MAX_ADDR_STR 32
+#define MAX_ADDR_STR 60
 
 static struct tipc_media *media_list[MAX_MEDIA];
 static u32 media_count;
@@ -89,9 +89,6 @@ int tipc_register_media(struct tipc_media *m_ptr)
 
 	if ((strlen(m_ptr->name) + 1) > TIPC_MAX_MEDIA_NAME)
 		goto exit;
-	if ((m_ptr->bcast_addr.media_id != m_ptr->type_id) ||
-	    !m_ptr->bcast_addr.broadcast)
-		goto exit;
 	if (m_ptr->priority > TIPC_MAX_LINK_PRI)
 		goto exit;
 	if ((m_ptr->tolerance < TIPC_MIN_LINK_TOL) ||
@@ -407,7 +404,7 @@ restart:
 	INIT_LIST_HEAD(&b_ptr->links);
 	spin_lock_init(&b_ptr->lock);
 
-	res = tipc_disc_create(b_ptr, &m_ptr->bcast_addr, disc_domain);
+	res = tipc_disc_create(b_ptr, &b_ptr->bcast_addr, disc_domain);
 	if (res) {
 		bearer_disable(b_ptr);
 		pr_warn("Bearer <%s> rejected, discovery object creation failed\n",
diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h
index 39f1192..09c869a 100644
--- a/net/tipc/bearer.h
+++ b/net/tipc/bearer.h
@@ -56,6 +56,7 @@
  * Identifiers of supported TIPC media types
  */
 #define TIPC_MEDIA_TYPE_ETH	1
+#define TIPC_MEDIA_TYPE_IB	2
 
 /**
  * struct tipc_media_addr - destination address used by TIPC bearers
@@ -77,7 +78,6 @@ struct tipc_bearer;
  * @enable_bearer: routine which enables a bearer
  * @disable_bearer: routine which disables a bearer
  * @addr2str: routine which converts media address to string
- * @str2addr: routine which converts media address from string
  * @addr2msg: routine which converts media address to protocol message area
  * @msg2addr: routine which converts media address from protocol message area
  * @bcast_addr: media address used in broadcasting
@@ -94,10 +94,9 @@ struct tipc_media {
 	int (*enable_bearer)(struct tipc_bearer *b_ptr);
 	void (*disable_bearer)(struct tipc_bearer *b_ptr);
 	int (*addr2str)(struct tipc_media_addr *a, char *str_buf, int str_size);
-	int (*str2addr)(struct tipc_media_addr *a, char *str_buf);
 	int (*addr2msg)(struct tipc_media_addr *a, char *msg_area);
-	int (*msg2addr)(struct tipc_media_addr *a, char *msg_area);
-	struct tipc_media_addr bcast_addr;
+	int (*msg2addr)(const struct tipc_bearer *b_ptr,
+			struct tipc_media_addr *a, char *msg_area);
 	u32 priority;
 	u32 tolerance;
 	u32 window;
@@ -136,6 +135,7 @@ struct tipc_bearer {
 	char name[TIPC_MAX_BEARER_NAME];
 	spinlock_t lock;
 	struct tipc_media *media;
+	struct tipc_media_addr bcast_addr;
 	u32 priority;
 	u32 window;
 	u32 tolerance;
@@ -175,6 +175,14 @@ int tipc_disable_bearer(const char *name);
 int  tipc_eth_media_start(void);
 void tipc_eth_media_stop(void);
 
+#ifdef CONFIG_TIPC_MEDIA_IB
+int  tipc_ib_media_start(void);
+void tipc_ib_media_stop(void);
+#else
+static inline int tipc_ib_media_start(void) { return 0; }
+static inline void tipc_ib_media_stop(void) { return; }
+#endif
+
 int tipc_media_set_priority(const char *name, u32 new_value);
 int tipc_media_set_window(const char *name, u32 new_value);
 void tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a);
diff --git a/net/tipc/core.c b/net/tipc/core.c
index fc05cec..7ec2c1e 100644
--- a/net/tipc/core.c
+++ b/net/tipc/core.c
@@ -82,6 +82,7 @@ static void tipc_core_stop_net(void)
 {
 	tipc_net_stop();
 	tipc_eth_media_stop();
+	tipc_ib_media_stop();
 }
 
 /**
@@ -93,8 +94,15 @@ int tipc_core_start_net(unsigned long addr)
 
 	tipc_net_start(addr);
 	res = tipc_eth_media_start();
-	if (res)
-		tipc_core_stop_net();
+	if (res < 0)
+		goto err;
+	res = tipc_ib_media_start();
+	if (res < 0)
+		goto err;
+	return res;
+
+err:
+	tipc_core_stop_net();
 	return res;
 }
 
diff --git a/net/tipc/discover.c b/net/tipc/discover.c
index 1074b95..eedff58 100644
--- a/net/tipc/discover.c
+++ b/net/tipc/discover.c
@@ -129,7 +129,7 @@ void tipc_disc_recv_msg(struct sk_buff *buf, struct tipc_bearer *b_ptr)
 	int link_fully_up;
 
 	media_addr.broadcast = 1;
-	b_ptr->media->msg2addr(&media_addr, msg_media_addr(msg));
+	b_ptr->media->msg2addr(b_ptr, &media_addr, msg_media_addr(msg));
 	kfree_skb(buf);
 
 	/* Ensure message from node is valid and communication is permitted */
diff --git a/net/tipc/eth_media.c b/net/tipc/eth_media.c
index 2132c1e..120a676 100644
--- a/net/tipc/eth_media.c
+++ b/net/tipc/eth_media.c
@@ -77,12 +77,13 @@ static struct notifier_block notifier = {
  * Media-dependent "value" field stores MAC address in first 6 bytes
  * and zeroes out the remaining bytes.
  */
-static void eth_media_addr_set(struct tipc_media_addr *a, char *mac)
+static void eth_media_addr_set(const struct tipc_bearer *tb_ptr,
+			       struct tipc_media_addr *a, char *mac)
 {
 	memcpy(a->value, mac, ETH_ALEN);
 	memset(a->value + ETH_ALEN, 0, sizeof(a->value) - ETH_ALEN);
 	a->media_id = TIPC_MEDIA_TYPE_ETH;
-	a->broadcast = !memcmp(mac, eth_media_info.bcast_addr.value, ETH_ALEN);
+	a->broadcast = !memcmp(mac, tb_ptr->bcast_addr.value, ETH_ALEN);
 }
 
 /**
@@ -110,6 +111,7 @@ static int send_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr,
 
 	skb_reset_network_header(clone);
 	clone->dev = dev;
+	clone->protocol = htons(ETH_P_TIPC);
 	dev_hard_header(clone, dev, ETH_P_TIPC, dest->value,
 			dev->dev_addr, clone->len);
 	dev_queue_xmit(clone);
@@ -201,9 +203,13 @@ static int enable_bearer(struct tipc_bearer *tb_ptr)
 	/* Associate TIPC bearer with Ethernet bearer */
 	eb_ptr->bearer = tb_ptr;
 	tb_ptr->usr_handle = (void *)eb_ptr;
+	memset(tb_ptr->bcast_addr.value, 0, sizeof(tb_ptr->bcast_addr.value));
+	memcpy(tb_ptr->bcast_addr.value, dev->broadcast, ETH_ALEN);
+	tb_ptr->bcast_addr.media_id = TIPC_MEDIA_TYPE_ETH;
+	tb_ptr->bcast_addr.broadcast = 1;
 	tb_ptr->mtu = dev->mtu;
 	tb_ptr->blocked = 0;
-	eth_media_addr_set(&tb_ptr->addr, (char *)dev->dev_addr);
+	eth_media_addr_set(tb_ptr, &tb_ptr->addr, (char *)dev->dev_addr);
 	return 0;
 }
 
@@ -302,25 +308,6 @@ static int eth_addr2str(struct tipc_media_addr *a, char *str_buf, int str_size)
 }
 
 /**
- * eth_str2addr - convert string to Ethernet address
- */
-static int eth_str2addr(struct tipc_media_addr *a, char *str_buf)
-{
-	char mac[ETH_ALEN];
-	int r;
-
-	r = sscanf(str_buf, "%02x:%02x:%02x:%02x:%02x:%02x",
-		       (u32 *)&mac[0], (u32 *)&mac[1], (u32 *)&mac[2],
-		       (u32 *)&mac[3], (u32 *)&mac[4], (u32 *)&mac[5]);
-
-	if (r != ETH_ALEN)
-		return 1;
-
-	eth_media_addr_set(a, mac);
-	return 0;
-}
-
-/**
  * eth_str2addr - convert Ethernet address format to message header format
  */
 static int eth_addr2msg(struct tipc_media_addr *a, char *msg_area)
@@ -334,12 +321,13 @@ static int eth_addr2msg(struct tipc_media_addr *a, char *msg_area)
 /**
  * eth_str2addr - convert message header address format to Ethernet format
  */
-static int eth_msg2addr(struct tipc_media_addr *a, char *msg_area)
+static int eth_msg2addr(const struct tipc_bearer *tb_ptr,
+			struct tipc_media_addr *a, char *msg_area)
 {
 	if (msg_area[TIPC_MEDIA_TYPE_OFFSET] != TIPC_MEDIA_TYPE_ETH)
 		return 1;
 
-	eth_media_addr_set(a, msg_area + ETH_ADDR_OFFSET);
+	eth_media_addr_set(tb_ptr, a, msg_area + ETH_ADDR_OFFSET);
 	return 0;
 }
 
@@ -351,11 +339,8 @@ static struct tipc_media eth_media_info = {
 	.enable_bearer	= enable_bearer,
 	.disable_bearer	= disable_bearer,
 	.addr2str	= eth_addr2str,
-	.str2addr	= eth_str2addr,
 	.addr2msg	= eth_addr2msg,
 	.msg2addr	= eth_msg2addr,
-	.bcast_addr	= { { 0xff, 0xff, 0xff, 0xff, 0xff, 0xff },
-			    TIPC_MEDIA_TYPE_ETH, 1 },
 	.priority	= TIPC_DEF_LINK_PRI,
 	.tolerance	= TIPC_DEF_LINK_TOL,
 	.window		= TIPC_DEF_LINK_WIN,
diff --git a/net/tipc/ib_media.c b/net/tipc/ib_media.c
new file mode 100644
index 0000000..2a2864c
--- /dev/null
+++ b/net/tipc/ib_media.c
@@ -0,0 +1,387 @@
+/*
+ * net/tipc/ib_media.c: Infiniband bearer support for TIPC
+ *
+ * Copyright (c) 2013 Patrick McHardy <kaber@trash.net>
+ *
+ * Based on eth_media.c, which carries the following copyright notice:
+ *
+ * Copyright (c) 2001-2007, Ericsson AB
+ * Copyright (c) 2005-2008, 2011, Wind River Systems
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/if_infiniband.h>
+#include "core.h"
+#include "bearer.h"
+
+#define MAX_IB_BEARERS		MAX_BEARERS
+
+/**
+ * struct ib_bearer - Infiniband bearer data structure
+ * @bearer: ptr to associated "generic" bearer structure
+ * @dev: ptr to associated Infiniband network device
+ * @tipc_packet_type: used in binding TIPC to Infiniband driver
+ * @cleanup: work item used when disabling bearer
+ */
+
+struct ib_bearer {
+	struct tipc_bearer *bearer;
+	struct net_device *dev;
+	struct packet_type tipc_packet_type;
+	struct work_struct setup;
+	struct work_struct cleanup;
+};
+
+static struct tipc_media ib_media_info;
+static struct ib_bearer ib_bearers[MAX_IB_BEARERS];
+static int ib_started;
+
+/**
+ * ib_media_addr_set - initialize Infiniband media address structure
+ *
+ * Media-dependent "value" field stores MAC address in first 6 bytes
+ * and zeroes out the remaining bytes.
+ */
+static void ib_media_addr_set(const struct tipc_bearer *tb_ptr,
+			      struct tipc_media_addr *a, char *mac)
+{
+	BUILD_BUG_ON(sizeof(a->value) < INFINIBAND_ALEN);
+	memcpy(a->value, mac, INFINIBAND_ALEN);
+	a->media_id = TIPC_MEDIA_TYPE_IB;
+	a->broadcast = !memcmp(mac, tb_ptr->bcast_addr.value, INFINIBAND_ALEN);
+}
+
+/**
+ * send_msg - send a TIPC message out over an InfiniBand interface
+ */
+static int send_msg(struct sk_buff *buf, struct tipc_bearer *tb_ptr,
+		    struct tipc_media_addr *dest)
+{
+	struct sk_buff *clone;
+	struct net_device *dev;
+	int delta;
+
+	clone = skb_clone(buf, GFP_ATOMIC);
+	if (!clone)
+		return 0;
+
+	dev = ((struct ib_bearer *)(tb_ptr->usr_handle))->dev;
+	delta = dev->hard_header_len - skb_headroom(buf);
+
+	if ((delta > 0) &&
+	    pskb_expand_head(clone, SKB_DATA_ALIGN(delta), 0, GFP_ATOMIC)) {
+		kfree_skb(clone);
+		return 0;
+	}
+
+	skb_reset_network_header(clone);
+	clone->dev = dev;
+	clone->protocol = htons(ETH_P_TIPC);
+	dev_hard_header(clone, dev, ETH_P_TIPC, dest->value,
+			dev->dev_addr, clone->len);
+	dev_queue_xmit(clone);
+	return 0;
+}
+
+/**
+ * recv_msg - handle incoming TIPC message from an InfiniBand interface
+ *
+ * Accept only packets explicitly sent to this node, or broadcast packets;
+ * ignores packets sent using InfiniBand multicast, and traffic sent to other
+ * nodes (which can happen if interface is running in promiscuous mode).
+ */
+static int recv_msg(struct sk_buff *buf, struct net_device *dev,
+		    struct packet_type *pt, struct net_device *orig_dev)
+{
+	struct ib_bearer *ib_ptr = (struct ib_bearer *)pt->af_packet_priv;
+
+	if (!net_eq(dev_net(dev), &init_net)) {
+		kfree_skb(buf);
+		return 0;
+	}
+
+	if (likely(ib_ptr->bearer)) {
+		if (likely(buf->pkt_type <= PACKET_BROADCAST)) {
+			buf->next = NULL;
+			tipc_recv_msg(buf, ib_ptr->bearer);
+			return 0;
+		}
+	}
+	kfree_skb(buf);
+	return 0;
+}
+
+/**
+ * setup_bearer - setup association between InfiniBand bearer and interface
+ */
+static void setup_bearer(struct work_struct *work)
+{
+	struct ib_bearer *ib_ptr =
+		container_of(work, struct ib_bearer, setup);
+
+	dev_add_pack(&ib_ptr->tipc_packet_type);
+}
+
+/**
+ * enable_bearer - attach TIPC bearer to an InfiniBand interface
+ */
+static int enable_bearer(struct tipc_bearer *tb_ptr)
+{
+	struct net_device *dev = NULL;
+	struct net_device *pdev = NULL;
+	struct ib_bearer *ib_ptr = &ib_bearers[0];
+	struct ib_bearer *stop = &ib_bearers[MAX_IB_BEARERS];
+	char *driver_name = strchr((const char *)tb_ptr->name, ':') + 1;
+	int pending_dev = 0;
+
+	/* Find unused InfiniBand bearer structure */
+	while (ib_ptr->dev) {
+		if (!ib_ptr->bearer)
+			pending_dev++;
+		if (++ib_ptr == stop)
+			return pending_dev ? -EAGAIN : -EDQUOT;
+	}
+
+	/* Find device with specified name */
+	read_lock(&dev_base_lock);
+	for_each_netdev(&init_net, pdev) {
+		if (!strncmp(pdev->name, driver_name, IFNAMSIZ)) {
+			dev = pdev;
+			dev_hold(dev);
+			break;
+		}
+	}
+	read_unlock(&dev_base_lock);
+	if (!dev)
+		return -ENODEV;
+
+	/* Create InfiniBand bearer for device */
+	ib_ptr->dev = dev;
+	ib_ptr->tipc_packet_type.type = htons(ETH_P_TIPC);
+	ib_ptr->tipc_packet_type.dev = dev;
+	ib_ptr->tipc_packet_type.func = recv_msg;
+	ib_ptr->tipc_packet_type.af_packet_priv = ib_ptr;
+	INIT_LIST_HEAD(&(ib_ptr->tipc_packet_type.list));
+	INIT_WORK(&ib_ptr->setup, setup_bearer);
+	schedule_work(&ib_ptr->setup);
+
+	/* Associate TIPC bearer with InfiniBand bearer */
+	ib_ptr->bearer = tb_ptr;
+	tb_ptr->usr_handle = (void *)ib_ptr;
+	memset(tb_ptr->bcast_addr.value, 0, sizeof(tb_ptr->bcast_addr.value));
+	memcpy(tb_ptr->bcast_addr.value, dev->broadcast, INFINIBAND_ALEN);
+	tb_ptr->bcast_addr.media_id = TIPC_MEDIA_TYPE_IB;
+	tb_ptr->bcast_addr.broadcast = 1;
+	tb_ptr->mtu = dev->mtu;
+	tb_ptr->blocked = 0;
+	ib_media_addr_set(tb_ptr, &tb_ptr->addr, (char *)dev->dev_addr);
+	return 0;
+}
+
+/**
+ * cleanup_bearer - break association between InfiniBand bearer and interface
+ *
+ * This routine must be invoked from a work queue because it can sleep.
+ */
+static void cleanup_bearer(struct work_struct *work)
+{
+	struct ib_bearer *ib_ptr =
+		container_of(work, struct ib_bearer, cleanup);
+
+	dev_remove_pack(&ib_ptr->tipc_packet_type);
+	dev_put(ib_ptr->dev);
+	ib_ptr->dev = NULL;
+}
+
+/**
+ * disable_bearer - detach TIPC bearer from an InfiniBand interface
+ *
+ * Mark InfiniBand bearer as inactive so that incoming buffers are thrown away,
+ * then get worker thread to complete bearer cleanup.  (Can't do cleanup
+ * here because cleanup code needs to sleep and caller holds spinlocks.)
+ */
+static void disable_bearer(struct tipc_bearer *tb_ptr)
+{
+	struct ib_bearer *ib_ptr = (struct ib_bearer *)tb_ptr->usr_handle;
+
+	ib_ptr->bearer = NULL;
+	INIT_WORK(&ib_ptr->cleanup, cleanup_bearer);
+	schedule_work(&ib_ptr->cleanup);
+}
+
+/**
+ * recv_notification - handle device updates from OS
+ *
+ * Change the state of the InfiniBand bearer (if any) associated with the
+ * specified device.
+ */
+static int recv_notification(struct notifier_block *nb, unsigned long evt,
+			     void *dv)
+{
+	struct net_device *dev = (struct net_device *)dv;
+	struct ib_bearer *ib_ptr = &ib_bearers[0];
+	struct ib_bearer *stop = &ib_bearers[MAX_IB_BEARERS];
+
+	if (!net_eq(dev_net(dev), &init_net))
+		return NOTIFY_DONE;
+
+	while ((ib_ptr->dev != dev)) {
+		if (++ib_ptr == stop)
+			return NOTIFY_DONE;	/* couldn't find device */
+	}
+	if (!ib_ptr->bearer)
+		return NOTIFY_DONE;		/* bearer had been disabled */
+
+	ib_ptr->bearer->mtu = dev->mtu;
+
+	switch (evt) {
+	case NETDEV_CHANGE:
+		if (netif_carrier_ok(dev))
+			tipc_continue(ib_ptr->bearer);
+		else
+			tipc_block_bearer(ib_ptr->bearer->name);
+		break;
+	case NETDEV_UP:
+		tipc_continue(ib_ptr->bearer);
+		break;
+	case NETDEV_DOWN:
+		tipc_block_bearer(ib_ptr->bearer->name);
+		break;
+	case NETDEV_CHANGEMTU:
+	case NETDEV_CHANGEADDR:
+		tipc_block_bearer(ib_ptr->bearer->name);
+		tipc_continue(ib_ptr->bearer);
+		break;
+	case NETDEV_UNREGISTER:
+	case NETDEV_CHANGENAME:
+		tipc_disable_bearer(ib_ptr->bearer->name);
+		break;
+	}
+	return NOTIFY_OK;
+}
+
+static struct notifier_block notifier = {
+	.notifier_call	= recv_notification,
+	.priority	= 0,
+};
+
+/**
+ * ib_addr2str - convert InfiniBand address to string
+ */
+static int ib_addr2str(struct tipc_media_addr *a, char *str_buf, int str_size)
+{
+	if (str_size < 60)	/* 60 = 19 * strlen("xx:") + strlen("xx\0") */
+		return 1;
+
+	sprintf(str_buf, "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:"
+			 "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x",
+		a->value[0], a->value[1], a->value[2], a->value[3],
+		a->value[4], a->value[5], a->value[6], a->value[7],
+		a->value[8], a->value[9], a->value[10], a->value[11],
+		a->value[12], a->value[13], a->value[14], a->value[15],
+		a->value[16], a->value[17], a->value[18], a->value[19]);
+
+	return 0;
+}
+
+/**
+ * ib_addr2msg - convert InfiniBand address format to message header format
+ */
+static int ib_addr2msg(struct tipc_media_addr *a, char *msg_area)
+{
+	memset(msg_area, 0, TIPC_MEDIA_ADDR_SIZE);
+	msg_area[TIPC_MEDIA_TYPE_OFFSET] = TIPC_MEDIA_TYPE_IB;
+	memcpy(msg_area, a->value, INFINIBAND_ALEN);
+	return 0;
+}
+
+/**
+ * ib_msg2addr - convert message header address format to InfiniBand format
+ */
+static int ib_msg2addr(const struct tipc_bearer *tb_ptr,
+		       struct tipc_media_addr *a, char *msg_area)
+{
+	ib_media_addr_set(tb_ptr, a, msg_area);
+	return 0;
+}
+
+/*
+ * InfiniBand media registration info
+ */
+static struct tipc_media ib_media_info = {
+	.send_msg	= send_msg,
+	.enable_bearer	= enable_bearer,
+	.disable_bearer	= disable_bearer,
+	.addr2str	= ib_addr2str,
+	.addr2msg	= ib_addr2msg,
+	.msg2addr	= ib_msg2addr,
+	.priority	= TIPC_DEF_LINK_PRI,
+	.tolerance	= TIPC_DEF_LINK_TOL,
+	.window		= TIPC_DEF_LINK_WIN,
+	.type_id	= TIPC_MEDIA_TYPE_IB,
+	.name		= "ib"
+};
+
+/**
+ * tipc_ib_media_start - activate InfiniBand bearer support
+ *
+ * Register InfiniBand media type with TIPC bearer code.  Also register
+ * with OS for notifications about device state changes.
+ */
+int tipc_ib_media_start(void)
+{
+	int res;
+
+	if (ib_started)
+		return -EINVAL;
+
+	res = tipc_register_media(&ib_media_info);
+	if (res)
+		return res;
+
+	res = register_netdevice_notifier(&notifier);
+	if (!res)
+		ib_started = 1;
+	return res;
+}
+
+/**
+ * tipc_ib_media_stop - deactivate InfiniBand bearer support
+ */
+void tipc_ib_media_stop(void)
+{
+	if (!ib_started)
+		return;
+
+	flush_scheduled_work();
+	unregister_netdevice_notifier(&notifier);
+	ib_started = 0;
+}