tipc: make tipc broadcast link support net namespace

TIPC broadcast link is statically established and its relevant states
are maintained with the global variables: "bcbearer", "bclink" and
"bcl". Allowing different namespace to own different broadcast link
instances, these variables must be moved to tipc_net structure and
broadcast link instances would be allocated and initialized when
namespace is created.

Signed-off-by: Ying Xue <ying.xue@windriver.com>
Tested-by: Tero Aho <Tero.Aho@coriant.com>
Reviewed-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

12 files changed, 259 insertions, 205 deletions

diff --git a/net/tipc/addr.c b/net/tipc/addr.c
index 357b74b..9e6eeb4 100644
--- a/net/tipc/addr.c
+++ b/net/tipc/addr.c
@@ -34,7 +34,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "core.h"
+#include <linux/kernel.h>
 #include "addr.h"
 
 /**
diff --git a/net/tipc/addr.h b/net/tipc/addr.h
index 3e1f18e..4e364c4 100644
--- a/net/tipc/addr.h
+++ b/net/tipc/addr.h
@@ -37,6 +37,9 @@
 #ifndef _TIPC_ADDR_H
 #define _TIPC_ADDR_H
 
+#include <linux/types.h>
+#include <linux/tipc.h>
+
 #define TIPC_ZONE_MASK		0xff000000u
 #define TIPC_CLUSTER_MASK	0xfffff000u
 
diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index e7c5383..bc58097 100644
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -35,77 +35,14 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 
-#include "core.h"
-#include "link.h"
 #include "socket.h"
 #include "msg.h"
 #include "bcast.h"
 #include "name_distr.h"
+#include "core.h"
 
 #define	MAX_PKT_DEFAULT_MCAST	1500	/* bcast link max packet size (fixed) */
 #define	BCLINK_WIN_DEFAULT	20	/* bcast link window size (default) */
-#define	BCBEARER		MAX_BEARERS
-
-/**
- * struct tipc_bcbearer_pair - a pair of bearers used by broadcast link
- * @primary: pointer to primary bearer
- * @secondary: pointer to secondary bearer
- *
- * Bearers must have same priority and same set of reachable destinations
- * to be paired.
- */
-
-struct tipc_bcbearer_pair {
-	struct tipc_bearer *primary;
-	struct tipc_bearer *secondary;
-};
-
-/**
- * struct tipc_bcbearer - bearer used by broadcast link
- * @bearer: (non-standard) broadcast bearer structure
- * @media: (non-standard) broadcast media structure
- * @bpairs: array of bearer pairs
- * @bpairs_temp: temporary array of bearer pairs used by tipc_bcbearer_sort()
- * @remains: temporary node map used by tipc_bcbearer_send()
- * @remains_new: temporary node map used tipc_bcbearer_send()
- *
- * Note: The fields labelled "temporary" are incorporated into the bearer
- * to avoid consuming potentially limited stack space through the use of
- * large local variables within multicast routines.  Concurrent access is
- * prevented through use of the spinlock "bclink_lock".
- */
-struct tipc_bcbearer {
-	struct tipc_bearer bearer;
-	struct tipc_media media;
-	struct tipc_bcbearer_pair bpairs[MAX_BEARERS];
-	struct tipc_bcbearer_pair bpairs_temp[TIPC_MAX_LINK_PRI + 1];
-	struct tipc_node_map remains;
-	struct tipc_node_map remains_new;
-};
-
-/**
- * struct tipc_bclink - link used for broadcast messages
- * @lock: spinlock governing access to structure
- * @link: (non-standard) broadcast link structure
- * @node: (non-standard) node structure representing b'cast link's peer node
- * @flags: represent bclink states
- * @bcast_nodes: map of broadcast-capable nodes
- * @retransmit_to: node that most recently requested a retransmit
- *
- * Handles sequence numbering, fragmentation, bundling, etc.
- */
-struct tipc_bclink {
-	spinlock_t lock;
-	struct tipc_link link;
-	struct tipc_node node;
-	unsigned int flags;
-	struct tipc_node_map bcast_nodes;
-	struct tipc_node *retransmit_to;
-};
-
-static struct tipc_bcbearer *bcbearer;
-static struct tipc_bclink *bclink;
-static struct tipc_link *bcl;
 
 const char tipc_bclink_name[] = "broadcast-link";
 
@@ -115,25 +52,28 @@ static void tipc_nmap_diff(struct tipc_node_map *nm_a,
 static void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node);
 static void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node);
 
-static void tipc_bclink_lock(void)
+static void tipc_bclink_lock(struct net *net)
 {
-	spin_lock_bh(&bclink->lock);
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+
+	spin_lock_bh(&tn->bclink->lock);
 }
 
-static void tipc_bclink_unlock(void)
+static void tipc_bclink_unlock(struct net *net)
 {
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	struct tipc_node *node = NULL;
 
-	if (likely(!bclink->flags)) {
-		spin_unlock_bh(&bclink->lock);
+	if (likely(!tn->bclink->flags)) {
+		spin_unlock_bh(&tn->bclink->lock);
 		return;
 	}
 
-	if (bclink->flags & TIPC_BCLINK_RESET) {
-		bclink->flags &= ~TIPC_BCLINK_RESET;
-		node = tipc_bclink_retransmit_to();
+	if (tn->bclink->flags & TIPC_BCLINK_RESET) {
+		tn->bclink->flags &= ~TIPC_BCLINK_RESET;
+		node = tipc_bclink_retransmit_to(net);
 	}
-	spin_unlock_bh(&bclink->lock);
+	spin_unlock_bh(&tn->bclink->lock);
 
 	if (node)
 		tipc_link_reset_all(node);
@@ -144,9 +84,11 @@ uint  tipc_bclink_get_mtu(void)
 	return MAX_PKT_DEFAULT_MCAST;
 }
 
-void tipc_bclink_set_flags(unsigned int flags)
+void tipc_bclink_set_flags(struct net *net, unsigned int flags)
 {
-	bclink->flags |= flags;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+
+	tn->bclink->flags |= flags;
 }
 
 static u32 bcbuf_acks(struct sk_buff *buf)
@@ -164,31 +106,40 @@ static void bcbuf_decr_acks(struct sk_buff *buf)
 	bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
 }
 
-void tipc_bclink_add_node(u32 addr)
+void tipc_bclink_add_node(struct net *net, u32 addr)
 {
-	tipc_bclink_lock();
-	tipc_nmap_add(&bclink->bcast_nodes, addr);
-	tipc_bclink_unlock();
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+
+	tipc_bclink_lock(net);
+	tipc_nmap_add(&tn->bclink->bcast_nodes, addr);
+	tipc_bclink_unlock(net);
 }
 
-void tipc_bclink_remove_node(u32 addr)
+void tipc_bclink_remove_node(struct net *net, u32 addr)
 {
-	tipc_bclink_lock();
-	tipc_nmap_remove(&bclink->bcast_nodes, addr);
-	tipc_bclink_unlock();
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+
+	tipc_bclink_lock(net);
+	tipc_nmap_remove(&tn->bclink->bcast_nodes, addr);
+	tipc_bclink_unlock(net);
 }
 
-static void bclink_set_last_sent(void)
+static void bclink_set_last_sent(struct net *net)
 {
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *bcl = tn->bcl;
+
 	if (bcl->next_out)
 		bcl->fsm_msg_cnt = mod(buf_seqno(bcl->next_out) - 1);
 	else
 		bcl->fsm_msg_cnt = mod(bcl->next_out_no - 1);
 }
 
-u32 tipc_bclink_get_last_sent(void)
+u32 tipc_bclink_get_last_sent(struct net *net)
 {
-	return bcl->fsm_msg_cnt;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+
+	return tn->bcl->fsm_msg_cnt;
 }
 
 static void bclink_update_last_sent(struct tipc_node *node, u32 seqno)
@@ -203,9 +154,11 @@ static void bclink_update_last_sent(struct tipc_node *node, u32 seqno)
  *
  * Called with bclink_lock locked
  */
-struct tipc_node *tipc_bclink_retransmit_to(void)
+struct tipc_node *tipc_bclink_retransmit_to(struct net *net)
 {
-	return bclink->retransmit_to;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+
+	return tn->bclink->retransmit_to;
 }
 
 /**
@@ -215,9 +168,10 @@ struct tipc_node *tipc_bclink_retransmit_to(void)
  *
  * Called with bclink_lock locked
  */
-static void bclink_retransmit_pkt(u32 after, u32 to)
+static void bclink_retransmit_pkt(struct tipc_net *tn, u32 after, u32 to)
 {
 	struct sk_buff *skb;
+	struct tipc_link *bcl = tn->bcl;
 
 	skb_queue_walk(&bcl->outqueue, skb) {
 		if (more(buf_seqno(skb), after)) {
@@ -234,9 +188,10 @@ static void bclink_retransmit_pkt(u32 after, u32 to)
  */
 void tipc_bclink_wakeup_users(struct net *net)
 {
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
 	struct sk_buff *skb;
 
-	while ((skb = skb_dequeue(&bclink->link.waiting_sks)))
+	while ((skb = skb_dequeue(&tn->bclink->link.waiting_sks)))
 		tipc_sk_rcv(net, skb);
 }
 
@@ -252,10 +207,12 @@ void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
 	struct sk_buff *skb, *tmp;
 	struct sk_buff *next;
 	unsigned int released = 0;
+	struct net *net = n_ptr->net;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
 
-	tipc_bclink_lock();
+	tipc_bclink_lock(net);
 	/* Bail out if tx queue is empty (no clean up is required) */
-	skb = skb_peek(&bcl->outqueue);
+	skb = skb_peek(&tn->bcl->outqueue);
 	if (!skb)
 		goto exit;
 
@@ -266,43 +223,43 @@ void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
 		 * acknowledge sent messages only (if other nodes still exist)
 		 * or both sent and unsent messages (otherwise)
 		 */
-		if (bclink->bcast_nodes.count)
-			acked = bcl->fsm_msg_cnt;
+		if (tn->bclink->bcast_nodes.count)
+			acked = tn->bcl->fsm_msg_cnt;
 		else
-			acked = bcl->next_out_no;
+			acked = tn->bcl->next_out_no;
 	} else {
 		/*
 		 * Bail out if specified sequence number does not correspond
 		 * to a message that has been sent and not yet acknowledged
 		 */
 		if (less(acked, buf_seqno(skb)) ||
-		    less(bcl->fsm_msg_cnt, acked) ||
+		    less(tn->bcl->fsm_msg_cnt, acked) ||
 		    less_eq(acked, n_ptr->bclink.acked))
 			goto exit;
 	}
 
 	/* Skip over packets that node has previously acknowledged */
-	skb_queue_walk(&bcl->outqueue, skb) {
+	skb_queue_walk(&tn->bcl->outqueue, skb) {
 		if (more(buf_seqno(skb), n_ptr->bclink.acked))
 			break;
 	}
 
 	/* Update packets that node is now acknowledging */
-	skb_queue_walk_from_safe(&bcl->outqueue, skb, tmp) {
+	skb_queue_walk_from_safe(&tn->bcl->outqueue, skb, tmp) {
 		if (more(buf_seqno(skb), acked))
 			break;
 
-		next = tipc_skb_queue_next(&bcl->outqueue, skb);
-		if (skb != bcl->next_out) {
+		next = tipc_skb_queue_next(&tn->bcl->outqueue, skb);
+		if (skb != tn->bcl->next_out) {
 			bcbuf_decr_acks(skb);
 		} else {
 			bcbuf_set_acks(skb, 0);
-			bcl->next_out = next;
-			bclink_set_last_sent();
+			tn->bcl->next_out = next;
+			bclink_set_last_sent(net);
 		}
 
 		if (bcbuf_acks(skb) == 0) {
-			__skb_unlink(skb, &bcl->outqueue);
+			__skb_unlink(skb, &tn->bcl->outqueue);
 			kfree_skb(skb);
 			released = 1;
 		}
@@ -310,15 +267,15 @@ void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
 	n_ptr->bclink.acked = acked;
 
 	/* Try resolving broadcast link congestion, if necessary */
-	if (unlikely(bcl->next_out)) {
-		tipc_link_push_packets(bcl);
-		bclink_set_last_sent();
+	if (unlikely(tn->bcl->next_out)) {
+		tipc_link_push_packets(tn->bcl);
+		bclink_set_last_sent(net);
 	}
-	if (unlikely(released && !skb_queue_empty(&bcl->waiting_sks)))
+	if (unlikely(released && !skb_queue_empty(&tn->bcl->waiting_sks)))
 		n_ptr->action_flags |= TIPC_WAKEUP_BCAST_USERS;
 
 exit:
-	tipc_bclink_unlock();
+	tipc_bclink_unlock(net);
 }
 
 /**
@@ -368,10 +325,10 @@ void tipc_bclink_update_link_state(struct net *net, struct tipc_node *n_ptr,
 		msg_set_bcgap_after(msg, n_ptr->bclink.last_in);
 		msg_set_bcgap_to(msg, to);
 
-		tipc_bclink_lock();
+		tipc_bclink_lock(net);
 		tipc_bearer_send(net, MAX_BEARERS, buf, NULL);
-		bcl->stats.sent_nacks++;
-		tipc_bclink_unlock();
+		tn->bcl->stats.sent_nacks++;
+		tipc_bclink_unlock(net);
 		kfree_skb(buf);
 
 		n_ptr->bclink.oos_state++;
@@ -410,6 +367,9 @@ static void bclink_peek_nack(struct net *net, struct tipc_msg *msg)
  */
 int tipc_bclink_xmit(struct net *net, struct sk_buff_head *list)
 {
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *bcl = tn->bcl;
+	struct tipc_bclink *bclink = tn->bclink;
 	int rc = 0;
 	int bc = 0;
 	struct sk_buff *skb;
@@ -423,19 +383,19 @@ int tipc_bclink_xmit(struct net *net, struct sk_buff_head *list)
 
 	/* Broadcast to all other nodes */
 	if (likely(bclink)) {
-		tipc_bclink_lock();
+		tipc_bclink_lock(net);
 		if (likely(bclink->bcast_nodes.count)) {
 			rc = __tipc_link_xmit(net, bcl, list);
 			if (likely(!rc)) {
 				u32 len = skb_queue_len(&bcl->outqueue);
 
-				bclink_set_last_sent();
+				bclink_set_last_sent(net);
 				bcl->stats.queue_sz_counts++;
 				bcl->stats.accu_queue_sz += len;
 			}
 			bc = 1;
 		}
-		tipc_bclink_unlock();
+		tipc_bclink_unlock(net);
 	}
 
 	if (unlikely(!bc))
@@ -457,10 +417,12 @@ int tipc_bclink_xmit(struct net *net, struct sk_buff_head *list)
  */
 static void bclink_accept_pkt(struct tipc_node *node, u32 seqno)
 {
+	struct tipc_net *tn = net_generic(node->net, tipc_net_id);
+
 	bclink_update_last_sent(node, seqno);
 	node->bclink.last_in = seqno;
 	node->bclink.oos_state = 0;
-	bcl->stats.recv_info++;
+	tn->bcl->stats.recv_info++;
 
 	/*
 	 * Unicast an ACK periodically, ensuring that
@@ -469,7 +431,7 @@ static void bclink_accept_pkt(struct tipc_node *node, u32 seqno)
 	if (((seqno - tipc_own_addr) % TIPC_MIN_LINK_WIN) == 0) {
 		tipc_link_proto_xmit(node->active_links[node->addr & 1],
 				     STATE_MSG, 0, 0, 0, 0, 0);
-		bcl->stats.sent_acks++;
+		tn->bcl->stats.sent_acks++;
 	}
 }
 
@@ -481,6 +443,7 @@ static void bclink_accept_pkt(struct tipc_node *node, u32 seqno)
 void tipc_bclink_rcv(struct net *net, struct sk_buff *buf)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *bcl = tn->bcl;
 	struct tipc_msg *msg = buf_msg(buf);
 	struct tipc_node *node;
 	u32 next_in;
@@ -506,12 +469,12 @@ void tipc_bclink_rcv(struct net *net, struct sk_buff *buf)
 		if (msg_destnode(msg) == tipc_own_addr) {
 			tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
 			tipc_node_unlock(node);
-			tipc_bclink_lock();
+			tipc_bclink_lock(net);
 			bcl->stats.recv_nacks++;
-			bclink->retransmit_to = node;
-			bclink_retransmit_pkt(msg_bcgap_after(msg),
+			tn->bclink->retransmit_to = node;
+			bclink_retransmit_pkt(tn, msg_bcgap_after(msg),
 					      msg_bcgap_to(msg));
-			tipc_bclink_unlock();
+			tipc_bclink_unlock(net);
 		} else {
 			tipc_node_unlock(node);
 			bclink_peek_nack(net, msg);
@@ -527,47 +490,47 @@ void tipc_bclink_rcv(struct net *net, struct sk_buff *buf)
 receive:
 		/* Deliver message to destination */
 		if (likely(msg_isdata(msg))) {
-			tipc_bclink_lock();
+			tipc_bclink_lock(net);
 			bclink_accept_pkt(node, seqno);
-			tipc_bclink_unlock();
+			tipc_bclink_unlock(net);
 			tipc_node_unlock(node);
 			if (likely(msg_mcast(msg)))
 				tipc_sk_mcast_rcv(net, buf);
 			else
 				kfree_skb(buf);
 		} else if (msg_user(msg) == MSG_BUNDLER) {
-			tipc_bclink_lock();
+			tipc_bclink_lock(net);
 			bclink_accept_pkt(node, seqno);
 			bcl->stats.recv_bundles++;
 			bcl->stats.recv_bundled += msg_msgcnt(msg);
-			tipc_bclink_unlock();
+			tipc_bclink_unlock(net);
 			tipc_node_unlock(node);
 			tipc_link_bundle_rcv(net, buf);
 		} else if (msg_user(msg) == MSG_FRAGMENTER) {
 			tipc_buf_append(&node->bclink.reasm_buf, &buf);
 			if (unlikely(!buf && !node->bclink.reasm_buf))
 				goto unlock;
-			tipc_bclink_lock();
+			tipc_bclink_lock(net);
 			bclink_accept_pkt(node, seqno);
 			bcl->stats.recv_fragments++;
 			if (buf) {
 				bcl->stats.recv_fragmented++;
 				msg = buf_msg(buf);
-				tipc_bclink_unlock();
+				tipc_bclink_unlock(net);
 				goto receive;
 			}
-			tipc_bclink_unlock();
+			tipc_bclink_unlock(net);
 			tipc_node_unlock(node);
 		} else if (msg_user(msg) == NAME_DISTRIBUTOR) {
-			tipc_bclink_lock();
+			tipc_bclink_lock(net);
 			bclink_accept_pkt(node, seqno);
-			tipc_bclink_unlock();
+			tipc_bclink_unlock(net);
 			tipc_node_unlock(node);
 			tipc_named_rcv(net, buf);
 		} else {
-			tipc_bclink_lock();
+			tipc_bclink_lock(net);
 			bclink_accept_pkt(node, seqno);
-			tipc_bclink_unlock();
+			tipc_bclink_unlock(net);
 			tipc_node_unlock(node);
 			kfree_skb(buf);
 		}
@@ -605,14 +568,14 @@ receive:
 		buf = NULL;
 	}
 
-	tipc_bclink_lock();
+	tipc_bclink_lock(net);
 
 	if (deferred)
 		bcl->stats.deferred_recv++;
 	else
 		bcl->stats.duplicates++;
 
-	tipc_bclink_unlock();
+	tipc_bclink_unlock(net);
 
 unlock:
 	tipc_node_unlock(node);
@@ -623,7 +586,7 @@ exit:
 u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
 {
 	return (n_ptr->bclink.recv_permitted &&
-		(tipc_bclink_get_last_sent() != n_ptr->bclink.acked));
+		(tipc_bclink_get_last_sent(n_ptr->net) != n_ptr->bclink.acked));
 }
 
 
@@ -636,13 +599,15 @@ u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
  * Returns 0 (packet sent successfully) under all circumstances,
  * since the broadcast link's pseudo-bearer never blocks
  */
-static int tipc_bcbearer_send(struct sk_buff *buf, struct tipc_bearer *unused1,
+static int tipc_bcbearer_send(struct net *net, struct sk_buff *buf,
+			      struct tipc_bearer *unused1,
 			      struct tipc_media_addr *unused2)
 {
 	int bp_index;
 	struct tipc_msg *msg = buf_msg(buf);
-	struct net *net = sock_net(buf->sk);
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_bcbearer *bcbearer = tn->bcbearer;
+	struct tipc_bclink *bclink = tn->bclink;
 
 	/* Prepare broadcast link message for reliable transmission,
 	 * if first time trying to send it;
@@ -653,7 +618,7 @@ static int tipc_bcbearer_send(struct sk_buff *buf, struct tipc_bearer *unused1,
 		bcbuf_set_acks(buf, bclink->bcast_nodes.count);
 		msg_set_non_seq(msg, 1);
 		msg_set_mc_netid(msg, tn->net_id);
-		bcl->stats.sent_info++;
+		tn->bcl->stats.sent_info++;
 
 		if (WARN_ON(!bclink->bcast_nodes.count)) {
 			dump_stack();
@@ -708,13 +673,14 @@ void tipc_bcbearer_sort(struct net *net, struct tipc_node_map *nm_ptr,
 			u32 node, bool action)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_bcbearer *bcbearer = tn->bcbearer;
 	struct tipc_bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
 	struct tipc_bcbearer_pair *bp_curr;
 	struct tipc_bearer *b;
 	int b_index;
 	int pri;
 
-	tipc_bclink_lock();
+	tipc_bclink_lock(net);
 
 	if (action)
 		tipc_nmap_add(nm_ptr, node);
@@ -761,7 +727,7 @@ void tipc_bcbearer_sort(struct net *net, struct tipc_node_map *nm_ptr,
 		bp_curr++;
 	}
 
-	tipc_bclink_unlock();
+	tipc_bclink_unlock(net);
 }
 
 static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
@@ -815,17 +781,19 @@ msg_full:
 	return -EMSGSIZE;
 }
 
-int tipc_nl_add_bc_link(struct tipc_nl_msg *msg)
+int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
 {
 	int err;
 	void *hdr;
 	struct nlattr *attrs;
 	struct nlattr *prop;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *bcl = tn->bcl;
 
 	if (!bcl)
 		return 0;
 
-	tipc_bclink_lock();
+	tipc_bclink_lock(net);
 
 	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_v2_family,
 			  NLM_F_MULTI, TIPC_NL_LINK_GET);
@@ -860,7 +828,7 @@ int tipc_nl_add_bc_link(struct tipc_nl_msg *msg)
 	if (err)
 		goto attr_msg_full;
 
-	tipc_bclink_unlock();
+	tipc_bclink_unlock(net);
 	nla_nest_end(msg->skb, attrs);
 	genlmsg_end(msg->skb, hdr);
 
@@ -871,21 +839,23 @@ prop_msg_full:
 attr_msg_full:
 	nla_nest_cancel(msg->skb, attrs);
 msg_full:
-	tipc_bclink_unlock();
+	tipc_bclink_unlock(net);
 	genlmsg_cancel(msg->skb, hdr);
 
 	return -EMSGSIZE;
 }
 
-int tipc_bclink_stats(char *buf, const u32 buf_size)
+int tipc_bclink_stats(struct net *net, char *buf, const u32 buf_size)
 {
 	int ret;
 	struct tipc_stats *s;
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *bcl = tn->bcl;
 
 	if (!bcl)
 		return 0;
 
-	tipc_bclink_lock();
+	tipc_bclink_lock(net);
 
 	s = &bcl->stats;
 
@@ -914,37 +884,46 @@ int tipc_bclink_stats(char *buf, const u32 buf_size)
 			     s->queue_sz_counts ?
 			     (s->accu_queue_sz / s->queue_sz_counts) : 0);
 
-	tipc_bclink_unlock();
+	tipc_bclink_unlock(net);
 	return ret;
 }
 
-int tipc_bclink_reset_stats(void)
+int tipc_bclink_reset_stats(struct net *net)
 {
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *bcl = tn->bcl;
+
 	if (!bcl)
 		return -ENOPROTOOPT;
 
-	tipc_bclink_lock();
+	tipc_bclink_lock(net);
 	memset(&bcl->stats, 0, sizeof(bcl->stats));
-	tipc_bclink_unlock();
+	tipc_bclink_unlock(net);
 	return 0;
 }
 
-int tipc_bclink_set_queue_limits(u32 limit)
+int tipc_bclink_set_queue_limits(struct net *net, u32 limit)
 {
+	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_link *bcl = tn->bcl;
+
 	if (!bcl)
 		return -ENOPROTOOPT;
 	if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
 		return -EINVAL;
 
-	tipc_bclink_lock();
+	tipc_bclink_lock(net);
 	tipc_link_set_queue_limits(bcl, limit);
-	tipc_bclink_unlock();
+	tipc_bclink_unlock(net);
 	return 0;
 }
 
 int tipc_bclink_init(struct net *net)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
+	struct tipc_bcbearer *bcbearer;
+	struct tipc_bclink *bclink;
+	struct tipc_link *bcl;
 
 	bcbearer = kzalloc(sizeof(*bcbearer), GFP_ATOMIC);
 	if (!bcbearer)
@@ -969,12 +948,16 @@ int tipc_bclink_init(struct net *net)
 	spin_lock_init(&bclink->node.lock);
 	__skb_queue_head_init(&bclink->node.waiting_sks);
 	bcl->owner = &bclink->node;
+	bcl->owner->net = net;
 	bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
 	tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
 	bcl->bearer_id = MAX_BEARERS;
 	rcu_assign_pointer(tn->bearer_list[MAX_BEARERS], &bcbearer->bearer);
 	bcl->state = WORKING_WORKING;
 	strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
+	tn->bcbearer = bcbearer;
+	tn->bclink = bclink;
+	tn->bcl = bcl;
 	return 0;
 }
 
@@ -982,14 +965,14 @@ void tipc_bclink_stop(struct net *net)
 {
 	struct tipc_net *tn = net_generic(net, tipc_net_id);
 
-	tipc_bclink_lock();
-	tipc_link_purge_queues(bcl);
-	tipc_bclink_unlock();
+	tipc_bclink_lock(net);
+	tipc_link_purge_queues(tn->bcl);
+	tipc_bclink_unlock(net);
 
 	RCU_INIT_POINTER(tn->bearer_list[BCBEARER], NULL);
 	synchronize_net();
-	kfree(bcbearer);
-	kfree(bclink);
+	kfree(tn->bcbearer);
+	kfree(tn->bclink);
 }
 
 /**
diff --git a/net/tipc/bcast.h b/net/tipc/bcast.h
index 692efb6..a4583a1 100644
--- a/net/tipc/bcast.h
+++ b/net/tipc/bcast.h
@@ -37,23 +37,13 @@
 #ifndef _TIPC_BCAST_H
 #define _TIPC_BCAST_H
 
-#include "netlink.h"
+#include <linux/tipc_config.h>
+#include "link.h"
+#include "node.h"
 
-#define MAX_NODES 4096
-#define WSIZE 32
-#define TIPC_BCLINK_RESET 1
-
-/**
- * struct tipc_node_map - set of node identifiers
- * @count: # of nodes in set
- * @map: bitmap of node identifiers that are in the set
- */
-struct tipc_node_map {
-	u32 count;
-	u32 map[MAX_NODES / WSIZE];
-};
-
-#define PLSIZE 32
+#define TIPC_BCLINK_RESET	1
+#define PLSIZE			32
+#define	BCBEARER		MAX_BEARERS
 
 /**
  * struct tipc_port_list - set of node local destination ports
@@ -67,9 +57,64 @@ struct tipc_port_list {
 	u32 ports[PLSIZE];
 };
 
+/**
+ * struct tipc_bcbearer_pair - a pair of bearers used by broadcast link
+ * @primary: pointer to primary bearer
+ * @secondary: pointer to secondary bearer
+ *
+ * Bearers must have same priority and same set of reachable destinations
+ * to be paired.
+ */
 
-struct tipc_node;
+struct tipc_bcbearer_pair {
+	struct tipc_bearer *primary;
+	struct tipc_bearer *secondary;
+};
 
+/**
+ * struct tipc_bcbearer - bearer used by broadcast link
+ * @bearer: (non-standard) broadcast bearer structure
+ * @media: (non-standard) broadcast media structure
+ * @bpairs: array of bearer pairs
+ * @bpairs_temp: temporary array of bearer pairs used by tipc_bcbearer_sort()
+ * @remains: temporary node map used by tipc_bcbearer_send()
+ * @remains_new: temporary node map used tipc_bcbearer_send()
+ *
+ * Note: The fields labelled "temporary" are incorporated into the bearer
+ * to avoid consuming potentially limited stack space through the use of
+ * large local variables within multicast routines.  Concurrent access is
+ * prevented through use of the spinlock "bclink_lock".
+ */
+struct tipc_bcbearer {
+	struct tipc_bearer bearer;
+	struct tipc_media media;
+	struct tipc_bcbearer_pair bpairs[MAX_BEARERS];
+	struct tipc_bcbearer_pair bpairs_temp[TIPC_MAX_LINK_PRI + 1];
+	struct tipc_node_map remains;
+	struct tipc_node_map remains_new;
+};
+
+/**
+ * struct tipc_bclink - link used for broadcast messages
+ * @lock: spinlock governing access to structure
+ * @link: (non-standard) broadcast link structure
+ * @node: (non-standard) node structure representing b'cast link's peer node
+ * @flags: represent bclink states
+ * @bcast_nodes: map of broadcast-capable nodes
+ * @retransmit_to: node that most recently requested a retransmit
+ *
+ * Handles sequence numbering, fragmentation, bundling, etc.
+ */
+struct tipc_bclink {
+	spinlock_t lock;
+	struct tipc_link link;
+	struct tipc_node node;
+	unsigned int flags;
+	struct tipc_node_map bcast_nodes;
+	struct tipc_node *retransmit_to;
+};
+
+struct tipc_node;
 extern const char tipc_bclink_name[];
 
 /**
@@ -86,24 +131,24 @@ void tipc_port_list_free(struct tipc_port_list *pl_ptr);
 
 int tipc_bclink_init(struct net *net);
 void tipc_bclink_stop(struct net *net);
-void tipc_bclink_set_flags(unsigned int flags);
-void tipc_bclink_add_node(u32 addr);
-void tipc_bclink_remove_node(u32 addr);
-struct tipc_node *tipc_bclink_retransmit_to(void);
+void tipc_bclink_set_flags(struct net *tn, unsigned int flags);
+void tipc_bclink_add_node(struct net *net, u32 addr);
+void tipc_bclink_remove_node(struct net *net, u32 addr);
+struct tipc_node *tipc_bclink_retransmit_to(struct net *tn);
 void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked);
 void tipc_bclink_rcv(struct net *net, struct sk_buff *buf);
-u32  tipc_bclink_get_last_sent(void);
+u32  tipc_bclink_get_last_sent(struct net *net);
 u32  tipc_bclink_acks_missing(struct tipc_node *n_ptr);
 void tipc_bclink_update_link_state(struct net *net, struct tipc_node *n_ptr,
 				   u32 last_sent);
-int  tipc_bclink_stats(char *stats_buf, const u32 buf_size);
-int  tipc_bclink_reset_stats(void);
-int  tipc_bclink_set_queue_limits(u32 limit);
+int  tipc_bclink_stats(struct net *net, char *stats_buf, const u32 buf_size);
+int  tipc_bclink_reset_stats(struct net *net);
+int  tipc_bclink_set_queue_limits(struct net *net, u32 limit);
 void tipc_bcbearer_sort(struct net *net, struct tipc_node_map *nm_ptr,
 			u32 node, bool action);
 uint  tipc_bclink_get_mtu(void);
 int tipc_bclink_xmit(struct net *net, struct sk_buff_head *list);
 void tipc_bclink_wakeup_users(struct net *net);
-int tipc_nl_add_bc_link(struct tipc_nl_msg *msg);
+int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg);
 
 #endif
diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index 2fe9dcb..9a0d6ed 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -40,6 +40,7 @@
 #include "bearer.h"
 #include "link.h"
 #include "discover.h"
+#include "bcast.h"
 
 #define MAX_ADDR_STR 60
 
@@ -482,8 +483,8 @@ void tipc_disable_l2_media(struct tipc_bearer *b)
  * @b_ptr: the bearer through which the packet is to be sent
  * @dest: peer destination address
  */
-int tipc_l2_send_msg(struct sk_buff *buf, struct tipc_bearer *b,
-		     struct tipc_media_addr *dest)
+int tipc_l2_send_msg(struct net *net, struct sk_buff *buf,
+		     struct tipc_bearer *b, struct tipc_media_addr *dest)
 {
 	struct sk_buff *clone;
 	struct net_device *dev;
@@ -528,7 +529,7 @@ void tipc_bearer_send(struct net *net, u32 bearer_id, struct sk_buff *buf,
 	rcu_read_lock();
 	b_ptr = rcu_dereference_rtnl(tn->bearer_list[bearer_id]);
 	if (likely(b_ptr))
-		b_ptr->media->send_msg(buf, b_ptr, dest);
+		b_ptr->media->send_msg(net, buf, b_ptr, dest);
 	rcu_read_unlock();
 }
 
diff --git a/net/tipc/bearer.h b/net/tipc/bearer.h
index 01722d6..c035e3e 100644
--- a/net/tipc/bearer.h
+++ b/net/tipc/bearer.h
@@ -37,12 +37,13 @@
 #ifndef _TIPC_BEARER_H
 #define _TIPC_BEARER_H
 
-#include "bcast.h"
 #include "netlink.h"
 #include <net/genetlink.h>
 
 #define MAX_BEARERS	2
 #define MAX_MEDIA	2
+#define MAX_NODES	4096
+#define WSIZE		32
 
 /* Identifiers associated with TIPC message header media address info
  * - address info field is 32 bytes long
@@ -59,6 +60,16 @@
 #define TIPC_MEDIA_TYPE_IB	2
 
 /**
+ * struct tipc_node_map - set of node identifiers
+ * @count: # of nodes in set
+ * @map: bitmap of node identifiers that are in the set
+ */
+struct tipc_node_map {
+	u32 count;
+	u32 map[MAX_NODES / WSIZE];
+};
+
+/**
  * struct tipc_media_addr - destination address used by TIPC bearers
  * @value: address info (format defined by media)
  * @media_id: TIPC media type identifier
@@ -89,7 +100,7 @@ struct tipc_bearer;
  * @name: media name
  */
 struct tipc_media {
-	int (*send_msg)(struct sk_buff *buf,
+	int (*send_msg)(struct net *net, struct sk_buff *buf,
 			struct tipc_bearer *b_ptr,
 			struct tipc_media_addr *dest);
 	int (*enable_media)(struct net *net, struct tipc_bearer *b_ptr);
@@ -157,8 +168,6 @@ struct tipc_bearer_names {
 	char if_name[TIPC_MAX_IF_NAME];
 };
 
-struct tipc_link;
-
 /*
  * TIPC routines available to supported media types
  */
@@ -193,8 +202,8 @@ void tipc_media_addr_printf(char *buf, int len, struct tipc_media_addr *a);
 struct sk_buff *tipc_media_get_names(void);
 int tipc_enable_l2_media(struct net *net, struct tipc_bearer *b);
 void tipc_disable_l2_media(struct tipc_bearer *b);
-int tipc_l2_send_msg(struct sk_buff *buf, struct tipc_bearer *b,
-		     struct tipc_media_addr *dest);
+int tipc_l2_send_msg(struct net *net, struct sk_buff *buf,
+		     struct tipc_bearer *b, struct tipc_media_addr *dest);
 
 struct sk_buff *tipc_bearer_get_names(struct net *net);
 void tipc_bearer_add_dest(struct net *net, u32 bearer_id, u32 dest);
diff --git a/net/tipc/core.h b/net/tipc/core.h
index 75a332b..3f6f9e0 100644
--- a/net/tipc/core.h
+++ b/net/tipc/core.h
@@ -61,6 +61,11 @@
 
 #include "node.h"
 #include "bearer.h"
+#include "bcast.h"
+#include "netlink.h"
+#include "link.h"
+#include "node.h"
+#include "msg.h"
 
 #define TIPC_MOD_VER "2.0.0"
 
@@ -91,6 +96,11 @@ struct tipc_net {
 
 	/* Bearer list */
 	struct tipc_bearer __rcu *bearer_list[MAX_BEARERS + 1];
+
+	/* Broadcast link */
+	struct tipc_bcbearer *bcbearer;
+	struct tipc_bclink *bclink;
+	struct tipc_link *bcl;
 };
 
 #ifdef CONFIG_SYSCTL
diff --git a/net/tipc/link.c b/net/tipc/link.c
index be21e6a..a84d5c6 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -941,6 +941,7 @@ static void link_retransmit_failure(struct tipc_link *l_ptr,
 				    struct sk_buff *buf)
 {
 	struct tipc_msg *msg = buf_msg(buf);
+	struct net *net = l_ptr->owner->net;
 
 	pr_warn("Retransmission failure on link <%s>\n", l_ptr->name);
 
@@ -958,7 +959,7 @@ static void link_retransmit_failure(struct tipc_link *l_ptr,
 		pr_cont("Outstanding acks: %lu\n",
 			(unsigned long) TIPC_SKB_CB(buf)->handle);
 
-		n_ptr = tipc_bclink_retransmit_to();
+		n_ptr = tipc_bclink_retransmit_to(net);
 		tipc_node_lock(n_ptr);
 
 		tipc_addr_string_fill(addr_string, n_ptr->addr);
@@ -973,7 +974,7 @@ static void link_retransmit_failure(struct tipc_link *l_ptr,
 
 		tipc_node_unlock(n_ptr);
 
-		tipc_bclink_set_flags(TIPC_BCLINK_RESET);
+		tipc_bclink_set_flags(net, TIPC_BCLINK_RESET);
 		l_ptr->stale_count = 0;
 	}
 }
@@ -1404,7 +1405,7 @@ void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg,
 	msg_set_type(msg, msg_typ);
 	msg_set_net_plane(msg, l_ptr->net_plane);
 	msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
-	msg_set_last_bcast(msg, tipc_bclink_get_last_sent());
+	msg_set_last_bcast(msg, tipc_bclink_get_last_sent(l_ptr->owner->net));
 
 	if (msg_typ == STATE_MSG) {
 		u32 next_sent = mod(l_ptr->next_out_no);
@@ -2105,7 +2106,7 @@ struct sk_buff *tipc_link_cmd_config(struct net *net, const void *req_tlv_area,
 
 	if (!strcmp(args->name, tipc_bclink_name)) {
 		if ((cmd == TIPC_CMD_SET_LINK_WINDOW) &&
-		    (tipc_bclink_set_queue_limits(new_value) == 0))
+		    (tipc_bclink_set_queue_limits(net, new_value) == 0))
 			return tipc_cfg_reply_none();
 		return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
 						   " (cannot change setting on broadcast link)");
@@ -2143,7 +2144,7 @@ struct sk_buff *tipc_link_cmd_reset_stats(struct net *net,
 
 	link_name = (char *)TLV_DATA(req_tlv_area);
 	if (!strcmp(link_name, tipc_bclink_name)) {
-		if (tipc_bclink_reset_stats())
+		if (tipc_bclink_reset_stats(net))
 			return tipc_cfg_reply_error_string("link not found");
 		return tipc_cfg_reply_none();
 	}
@@ -2191,7 +2192,7 @@ static int tipc_link_stats(struct net *net, const char *name, char *buf,
 	int ret;
 
 	if (!strcmp(name, tipc_bclink_name))
-		return tipc_bclink_stats(buf, buf_size);
+		return tipc_bclink_stats(net, buf, buf_size);
 
 	node = tipc_link_find_owner(net, name, &bearer_id);
 	if (!node)
@@ -2640,7 +2641,7 @@ int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
 			prev_node = node->addr;
 		}
 	} else {
-		err = tipc_nl_add_bc_link(&msg);
+		err = tipc_nl_add_bc_link(net, &msg);
 		if (err)
 			goto out;
 
@@ -2739,7 +2740,7 @@ int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
 	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
 
 	if (strcmp(link_name, tipc_bclink_name) == 0) {
-		err = tipc_bclink_reset_stats();
+		err = tipc_bclink_reset_stats(net);
 		if (err)
 			return err;
 		return 0;
diff --git a/net/tipc/msg.h b/net/tipc/msg.h
index 0065a2e..75f3242 100644
--- a/net/tipc/msg.h
+++ b/net/tipc/msg.h
@@ -37,7 +37,7 @@
 #ifndef _TIPC_MSG_H
 #define _TIPC_MSG_H
 
-#include "bearer.h"
+#include <linux/tipc.h>
 
 /*
  * Constants and routines used to read and write TIPC payload message headers
diff --git a/net/tipc/name_table.c b/net/tipc/name_table.c
index cf17790..beed5fd 100644
--- a/net/tipc/name_table.c
+++ b/net/tipc/name_table.c
@@ -39,6 +39,7 @@
 #include "name_table.h"
 #include "name_distr.h"
 #include "subscr.h"
+#include "bcast.h"
 
 #define TIPC_NAMETBL_SIZE 1024		/* must be a power of 2 */
 
diff --git a/net/tipc/net.c b/net/tipc/net.c
index 38633e5..7548ba8 100644
--- a/net/tipc/net.c
+++ b/net/tipc/net.c
@@ -41,6 +41,7 @@
 #include "socket.h"
 #include "node.h"
 #include "config.h"
+#include "bcast.h"
 
 static const struct nla_policy tipc_nl_net_policy[TIPC_NLA_NET_MAX + 1] = {
 	[TIPC_NLA_NET_UNSPEC]	= { .type = NLA_UNSPEC },
diff --git a/net/tipc/node.c b/net/tipc/node.c
index a0ca1ac..3db5012 100644
--- a/net/tipc/node.c
+++ b/net/tipc/node.c
@@ -368,8 +368,8 @@ static void node_established_contact(struct tipc_node *n_ptr)
 {
 	n_ptr->action_flags |= TIPC_NOTIFY_NODE_UP;
 	n_ptr->bclink.oos_state = 0;
-	n_ptr->bclink.acked = tipc_bclink_get_last_sent();
-	tipc_bclink_add_node(n_ptr->addr);
+	n_ptr->bclink.acked = tipc_bclink_get_last_sent(n_ptr->net);
+	tipc_bclink_add_node(n_ptr->net, n_ptr->addr);
 }
 
 static void node_lost_contact(struct tipc_node *n_ptr)
@@ -389,7 +389,7 @@ static void node_lost_contact(struct tipc_node *n_ptr)
 			n_ptr->bclink.reasm_buf = NULL;
 		}
 
-		tipc_bclink_remove_node(n_ptr->addr);
+		tipc_bclink_remove_node(n_ptr->net, n_ptr->addr);
 		tipc_bclink_acknowledge(n_ptr, INVALID_LINK_SEQ);
 
 		n_ptr->bclink.recv_permitted = false;