1 files changed, 676 insertions, 305 deletions

diff --git a/net/tipc/link.c b/net/tipc/link.c
index 1db162aa64a5..23bcc1132365 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -36,10 +36,12 @@
 
 #include "core.h"
 #include "link.h"
+#include "bcast.h"
 #include "socket.h"
 #include "name_distr.h"
 #include "discover.h"
 #include "config.h"
+#include "netlink.h"
 
 #include <linux/pkt_sched.h>
 
@@ -50,6 +52,30 @@ static const char *link_co_err = "Link changeover error, ";
 static const char *link_rst_msg = "Resetting link ";
 static const char *link_unk_evt = "Unknown link event ";
 
+static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = {
+	[TIPC_NLA_LINK_UNSPEC]		= { .type = NLA_UNSPEC },
+	[TIPC_NLA_LINK_NAME] = {
+		.type = NLA_STRING,
+		.len = TIPC_MAX_LINK_NAME
+	},
+	[TIPC_NLA_LINK_MTU]		= { .type = NLA_U32 },
+	[TIPC_NLA_LINK_BROADCAST]	= { .type = NLA_FLAG },
+	[TIPC_NLA_LINK_UP]		= { .type = NLA_FLAG },
+	[TIPC_NLA_LINK_ACTIVE]		= { .type = NLA_FLAG },
+	[TIPC_NLA_LINK_PROP]		= { .type = NLA_NESTED },
+	[TIPC_NLA_LINK_STATS]		= { .type = NLA_NESTED },
+	[TIPC_NLA_LINK_RX]		= { .type = NLA_U32 },
+	[TIPC_NLA_LINK_TX]		= { .type = NLA_U32 }
+};
+
+/* Properties valid for media, bearar and link */
+static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = {
+	[TIPC_NLA_PROP_UNSPEC]		= { .type = NLA_UNSPEC },
+	[TIPC_NLA_PROP_PRIO]		= { .type = NLA_U32 },
+	[TIPC_NLA_PROP_TOL]		= { .type = NLA_U32 },
+	[TIPC_NLA_PROP_WIN]		= { .type = NLA_U32 }
+};
+
 /*
  * Out-of-range value for link session numbers
  */
@@ -123,18 +149,6 @@ static void link_init_max_pkt(struct tipc_link *l_ptr)
 	l_ptr->max_pkt_probes = 0;
 }
 
-static u32 link_next_sent(struct tipc_link *l_ptr)
-{
-	if (l_ptr->next_out)
-		return buf_seqno(l_ptr->next_out);
-	return mod(l_ptr->next_out_no);
-}
-
-static u32 link_last_sent(struct tipc_link *l_ptr)
-{
-	return mod(link_next_sent(l_ptr) - 1);
-}
-
 /*
  *  Simple non-static link routines (i.e. referenced outside this file)
  */
@@ -157,14 +171,17 @@ int tipc_link_is_active(struct tipc_link *l_ptr)
  */
 static void link_timeout(struct tipc_link *l_ptr)
 {
+	struct sk_buff *skb;
+
 	tipc_node_lock(l_ptr->owner);
 
 	/* update counters used in statistical profiling of send traffic */
-	l_ptr->stats.accu_queue_sz += l_ptr->out_queue_size;
+	l_ptr->stats.accu_queue_sz += skb_queue_len(&l_ptr->outqueue);
 	l_ptr->stats.queue_sz_counts++;
 
-	if (l_ptr->first_out) {
-		struct tipc_msg *msg = buf_msg(l_ptr->first_out);
+	skb = skb_peek(&l_ptr->outqueue);
+	if (skb) {
+		struct tipc_msg *msg = buf_msg(skb);
 		u32 length = msg_size(msg);
 
 		if ((msg_user(msg) == MSG_FRAGMENTER) &&
@@ -192,11 +209,10 @@ static void link_timeout(struct tipc_link *l_ptr)
 	}
 
 	/* do all other link processing performed on a periodic basis */
-
 	link_state_event(l_ptr, TIMEOUT_EVT);
 
 	if (l_ptr->next_out)
-		tipc_link_push_queue(l_ptr);
+		tipc_link_push_packets(l_ptr);
 
 	tipc_node_unlock(l_ptr->owner);
 }
@@ -224,9 +240,10 @@ struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
 	char addr_string[16];
 	u32 peer = n_ptr->addr;
 
-	if (n_ptr->link_cnt >= 2) {
+	if (n_ptr->link_cnt >= MAX_BEARERS) {
 		tipc_addr_string_fill(addr_string, n_ptr->addr);
-		pr_err("Attempt to establish third link to %s\n", addr_string);
+		pr_err("Attempt to establish %uth link to %s. Max %u allowed.\n",
+			n_ptr->link_cnt, addr_string, MAX_BEARERS);
 		return NULL;
 	}
 
@@ -274,7 +291,9 @@ struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
 	link_init_max_pkt(l_ptr);
 
 	l_ptr->next_out_no = 1;
-	__skb_queue_head_init(&l_ptr->waiting_sks);
+	__skb_queue_head_init(&l_ptr->outqueue);
+	__skb_queue_head_init(&l_ptr->deferred_queue);
+	skb_queue_head_init(&l_ptr->waiting_sks);
 
 	link_reset_statistics(l_ptr);
 
@@ -339,7 +358,7 @@ static bool link_schedule_user(struct tipc_link *link, u32 oport,
 		return false;
 	TIPC_SKB_CB(buf)->chain_sz = chain_sz;
 	TIPC_SKB_CB(buf)->chain_imp = imp;
-	__skb_queue_tail(&link->waiting_sks, buf);
+	skb_queue_tail(&link->waiting_sks, buf);
 	link->stats.link_congs++;
 	return true;
 }
@@ -352,30 +371,19 @@ static bool link_schedule_user(struct tipc_link *link, u32 oport,
  */
 static void link_prepare_wakeup(struct tipc_link *link)
 {
-	struct sk_buff_head *wq = &link->waiting_sks;
-	struct sk_buff *buf;
-	uint pend_qsz = link->out_queue_size;
+	uint pend_qsz = skb_queue_len(&link->outqueue);
+	struct sk_buff *skb, *tmp;
 
-	for (buf = skb_peek(wq); buf; buf = skb_peek(wq)) {
-		if (pend_qsz >= link->queue_limit[TIPC_SKB_CB(buf)->chain_imp])
+	skb_queue_walk_safe(&link->waiting_sks, skb, tmp) {
+		if (pend_qsz >= link->queue_limit[TIPC_SKB_CB(skb)->chain_imp])
 			break;
-		pend_qsz += TIPC_SKB_CB(buf)->chain_sz;
-		__skb_queue_tail(&link->owner->waiting_sks, __skb_dequeue(wq));
+		pend_qsz += TIPC_SKB_CB(skb)->chain_sz;
+		skb_unlink(skb, &link->waiting_sks);
+		skb_queue_tail(&link->owner->waiting_sks, skb);
 	}
 }
 
 /**
- * link_release_outqueue - purge link's outbound message queue
- * @l_ptr: pointer to link
- */
-static void link_release_outqueue(struct tipc_link *l_ptr)
-{
-	kfree_skb_list(l_ptr->first_out);
-	l_ptr->first_out = NULL;
-	l_ptr->out_queue_size = 0;
-}
-
-/**
  * tipc_link_reset_fragments - purge link's inbound message fragments queue
  * @l_ptr: pointer to link
  */
@@ -391,11 +399,9 @@ void tipc_link_reset_fragments(struct tipc_link *l_ptr)
  */
 void tipc_link_purge_queues(struct tipc_link *l_ptr)
 {
-	kfree_skb_list(l_ptr->oldest_deferred_in);
-	kfree_skb_list(l_ptr->first_out);
+	__skb_queue_purge(&l_ptr->deferred_queue);
+	__skb_queue_purge(&l_ptr->outqueue);
 	tipc_link_reset_fragments(l_ptr);
-	kfree_skb(l_ptr->proto_msg_queue);
-	l_ptr->proto_msg_queue = NULL;
 }
 
 void tipc_link_reset(struct tipc_link *l_ptr)
@@ -427,25 +433,16 @@ void tipc_link_reset(struct tipc_link *l_ptr)
 	}
 
 	/* Clean up all queues: */
-	link_release_outqueue(l_ptr);
-	kfree_skb(l_ptr->proto_msg_queue);
-	l_ptr->proto_msg_queue = NULL;
-	kfree_skb_list(l_ptr->oldest_deferred_in);
+	__skb_queue_purge(&l_ptr->outqueue);
+	__skb_queue_purge(&l_ptr->deferred_queue);
 	if (!skb_queue_empty(&l_ptr->waiting_sks)) {
 		skb_queue_splice_init(&l_ptr->waiting_sks, &owner->waiting_sks);
 		owner->action_flags |= TIPC_WAKEUP_USERS;
 	}
-	l_ptr->retransm_queue_head = 0;
-	l_ptr->retransm_queue_size = 0;
-	l_ptr->last_out = NULL;
-	l_ptr->first_out = NULL;
 	l_ptr->next_out = NULL;
 	l_ptr->unacked_window = 0;
 	l_ptr->checkpoint = 1;
 	l_ptr->next_out_no = 1;
-	l_ptr->deferred_inqueue_sz = 0;
-	l_ptr->oldest_deferred_in = NULL;
-	l_ptr->newest_deferred_in = NULL;
 	l_ptr->fsm_msg_cnt = 0;
 	l_ptr->stale_count = 0;
 	link_reset_statistics(l_ptr);
@@ -667,9 +664,10 @@ static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
  * - For all other messages we discard the buffer and return -EHOSTUNREACH
  * - For TIPC internal messages we also reset the link
  */
-static int tipc_link_cong(struct tipc_link *link, struct sk_buff *buf)
+static int tipc_link_cong(struct tipc_link *link, struct sk_buff_head *list)
 {
-	struct tipc_msg *msg = buf_msg(buf);
+	struct sk_buff *skb = skb_peek(list);
+	struct tipc_msg *msg = buf_msg(skb);
 	uint imp = tipc_msg_tot_importance(msg);
 	u32 oport = msg_tot_origport(msg);
 
@@ -682,30 +680,30 @@ static int tipc_link_cong(struct tipc_link *link, struct sk_buff *buf)
 		goto drop;
 	if (unlikely(msg_reroute_cnt(msg)))
 		goto drop;
-	if (TIPC_SKB_CB(buf)->wakeup_pending)
+	if (TIPC_SKB_CB(skb)->wakeup_pending)
 		return -ELINKCONG;
-	if (link_schedule_user(link, oport, TIPC_SKB_CB(buf)->chain_sz, imp))
+	if (link_schedule_user(link, oport, skb_queue_len(list), imp))
 		return -ELINKCONG;
 drop:
-	kfree_skb_list(buf);
+	__skb_queue_purge(list);
 	return -EHOSTUNREACH;
 }
 
 /**
  * __tipc_link_xmit(): same as tipc_link_xmit, but destlink is known & locked
  * @link: link to use
- * @buf: chain of buffers containing message
+ * @list: chain of buffers containing message
+ *
  * Consumes the buffer chain, except when returning -ELINKCONG
  * Returns 0 if success, otherwise errno: -ELINKCONG, -EMSGSIZE (plain socket
  * user data messages) or -EHOSTUNREACH (all other messages/senders)
  * Only the socket functions tipc_send_stream() and tipc_send_packet() need
  * to act on the return value, since they may need to do more send attempts.
  */
-int __tipc_link_xmit(struct tipc_link *link, struct sk_buff *buf)
+int __tipc_link_xmit(struct tipc_link *link, struct sk_buff_head *list)
 {
-	struct tipc_msg *msg = buf_msg(buf);
+	struct tipc_msg *msg = buf_msg(skb_peek(list));
 	uint psz = msg_size(msg);
-	uint qsz = link->out_queue_size;
 	uint sndlim = link->queue_limit[0];
 	uint imp = tipc_msg_tot_importance(msg);
 	uint mtu = link->max_pkt;
@@ -713,71 +711,83 @@ int __tipc_link_xmit(struct tipc_link *link, struct sk_buff *buf)
 	uint seqno = link->next_out_no;
 	uint bc_last_in = link->owner->bclink.last_in;
 	struct tipc_media_addr *addr = &link->media_addr;
-	struct sk_buff *next = buf->next;
+	struct sk_buff_head *outqueue = &link->outqueue;
+	struct sk_buff *skb, *tmp;
 
 	/* Match queue limits against msg importance: */
-	if (unlikely(qsz >= link->queue_limit[imp]))
-		return tipc_link_cong(link, buf);
+	if (unlikely(skb_queue_len(outqueue) >= link->queue_limit[imp]))
+		return tipc_link_cong(link, list);
 
 	/* Has valid packet limit been used ? */
 	if (unlikely(psz > mtu)) {
-		kfree_skb_list(buf);
+		__skb_queue_purge(list);
 		return -EMSGSIZE;
 	}
 
 	/* Prepare each packet for sending, and add to outqueue: */
-	while (buf) {
-		next = buf->next;
-		msg = buf_msg(buf);
+	skb_queue_walk_safe(list, skb, tmp) {
+		__skb_unlink(skb, list);
+		msg = buf_msg(skb);
 		msg_set_word(msg, 2, ((ack << 16) | mod(seqno)));
 		msg_set_bcast_ack(msg, bc_last_in);
 
-		if (!link->first_out) {
-			link->first_out = buf;
-		} else if (qsz < sndlim) {
-			link->last_out->next = buf;
-		} else if (tipc_msg_bundle(link->last_out, buf, mtu)) {
+		if (skb_queue_len(outqueue) < sndlim) {
+			__skb_queue_tail(outqueue, skb);
+			tipc_bearer_send(link->bearer_id, skb, addr);
+			link->next_out = NULL;
+			link->unacked_window = 0;
+		} else if (tipc_msg_bundle(outqueue, skb, mtu)) {
 			link->stats.sent_bundled++;
-			buf = next;
-			next = buf->next;
 			continue;
-		} else if (tipc_msg_make_bundle(&buf, mtu, link->addr)) {
+		} else if (tipc_msg_make_bundle(outqueue, skb, mtu,
+						link->addr)) {
 			link->stats.sent_bundled++;
 			link->stats.sent_bundles++;
-			link->last_out->next = buf;
 			if (!link->next_out)
-				link->next_out = buf;
+				link->next_out = skb_peek_tail(outqueue);
 		} else {
-			link->last_out->next = buf;
+			__skb_queue_tail(outqueue, skb);
 			if (!link->next_out)
-				link->next_out = buf;
-		}
-
-		/* Send packet if possible: */
-		if (likely(++qsz <= sndlim)) {
-			tipc_bearer_send(link->bearer_id, buf, addr);
-			link->next_out = next;
-			link->unacked_window = 0;
+				link->next_out = skb;
 		}
 		seqno++;
-		link->last_out = buf;
-		buf = next;
 	}
 	link->next_out_no = seqno;
-	link->out_queue_size = qsz;
 	return 0;
 }
 
+static void skb2list(struct sk_buff *skb, struct sk_buff_head *list)
+{
+	__skb_queue_head_init(list);
+	__skb_queue_tail(list, skb);
+}
+
+static int __tipc_link_xmit_skb(struct tipc_link *link, struct sk_buff *skb)
+{
+	struct sk_buff_head head;
+
+	skb2list(skb, &head);
+	return __tipc_link_xmit(link, &head);
+}
+
+int tipc_link_xmit_skb(struct sk_buff *skb, u32 dnode, u32 selector)
+{
+	struct sk_buff_head head;
+
+	skb2list(skb, &head);
+	return tipc_link_xmit(&head, dnode, selector);
+}
+
 /**
  * tipc_link_xmit() is the general link level function for message sending
- * @buf: chain of buffers containing message
+ * @list: chain of buffers containing message
  * @dsz: amount of user data to be sent
  * @dnode: address of destination node
  * @selector: a number used for deterministic link selection
  * Consumes the buffer chain, except when returning -ELINKCONG
  * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
  */
-int tipc_link_xmit(struct sk_buff *buf, u32 dnode, u32 selector)
+int tipc_link_xmit(struct sk_buff_head *list, u32 dnode, u32 selector)
 {
 	struct tipc_link *link = NULL;
 	struct tipc_node *node;
@@ -788,17 +798,22 @@ int tipc_link_xmit(struct sk_buff *buf, u32 dnode, u32 selector)
 		tipc_node_lock(node);
 		link = node->active_links[selector & 1];
 		if (link)
-			rc = __tipc_link_xmit(link, buf);
+			rc = __tipc_link_xmit(link, list);
 		tipc_node_unlock(node);
 	}
 
 	if (link)
 		return rc;
 
-	if (likely(in_own_node(dnode)))
-		return tipc_sk_rcv(buf);
+	if (likely(in_own_node(dnode))) {
+		/* As a node local message chain never contains more than one
+		 * buffer, we just need to dequeue one SKB buffer from the
+		 * head list.
+		 */
+		return tipc_sk_rcv(__skb_dequeue(list));
+	}
+	__skb_queue_purge(list);
 
-	kfree_skb_list(buf);
 	return rc;
 }
 
@@ -812,17 +827,17 @@ int tipc_link_xmit(struct sk_buff *buf, u32 dnode, u32 selector)
  */
 static void tipc_link_sync_xmit(struct tipc_link *link)
 {
-	struct sk_buff *buf;
+	struct sk_buff *skb;
 	struct tipc_msg *msg;
 
-	buf = tipc_buf_acquire(INT_H_SIZE);
-	if (!buf)
+	skb = tipc_buf_acquire(INT_H_SIZE);
+	if (!skb)
 		return;
 
-	msg = buf_msg(buf);
+	msg = buf_msg(skb);
 	tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE, link->addr);
 	msg_set_last_bcast(msg, link->owner->bclink.acked);
-	__tipc_link_xmit(link, buf);
+	__tipc_link_xmit_skb(link, skb);
 }
 
 /*
@@ -842,85 +857,46 @@ static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf)
 	kfree_skb(buf);
 }
 
+struct sk_buff *tipc_skb_queue_next(const struct sk_buff_head *list,
+				    const struct sk_buff *skb)
+{
+	if (skb_queue_is_last(list, skb))
+		return NULL;
+	return skb->next;
+}
+
 /*
- * tipc_link_push_packet: Push one unsent packet to the media
+ * tipc_link_push_packets - push unsent packets to bearer
+ *
+ * Push out the unsent messages of a link where congestion
+ * has abated. Node is locked.
+ *
+ * Called with node locked
  */
-static u32 tipc_link_push_packet(struct tipc_link *l_ptr)
-{
-	struct sk_buff *buf = l_ptr->first_out;
-	u32 r_q_size = l_ptr->retransm_queue_size;
-	u32 r_q_head = l_ptr->retransm_queue_head;
-
-	/* Step to position where retransmission failed, if any,    */
-	/* consider that buffers may have been released in meantime */
-	if (r_q_size && buf) {
-		u32 last = lesser(mod(r_q_head + r_q_size),
-				  link_last_sent(l_ptr));
-		u32 first = buf_seqno(buf);
-
-		while (buf && less(first, r_q_head)) {
-			first = mod(first + 1);
-			buf = buf->next;
-		}
-		l_ptr->retransm_queue_head = r_q_head = first;
-		l_ptr->retransm_queue_size = r_q_size = mod(last - first);
-	}
-
-	/* Continue retransmission now, if there is anything: */
-	if (r_q_size && buf) {
-		msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
-		msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
-		tipc_bearer_send(l_ptr->bearer_id, buf, &l_ptr->media_addr);
-		l_ptr->retransm_queue_head = mod(++r_q_head);
-		l_ptr->retransm_queue_size = --r_q_size;
-		l_ptr->stats.retransmitted++;
-		return 0;
-	}
-
-	/* Send deferred protocol message, if any: */
-	buf = l_ptr->proto_msg_queue;
-	if (buf) {
-		msg_set_ack(buf_msg(buf), mod(l_ptr->next_in_no - 1));
-		msg_set_bcast_ack(buf_msg(buf), l_ptr->owner->bclink.last_in);
-		tipc_bearer_send(l_ptr->bearer_id, buf, &l_ptr->media_addr);
-		l_ptr->unacked_window = 0;
-		kfree_skb(buf);
-		l_ptr->proto_msg_queue = NULL;
-		return 0;
-	}
+void tipc_link_push_packets(struct tipc_link *l_ptr)
+{
+	struct sk_buff_head *outqueue = &l_ptr->outqueue;
+	struct sk_buff *skb = l_ptr->next_out;
+	struct tipc_msg *msg;
+	u32 next, first;
 
-	/* Send one deferred data message, if send window not full: */
-	buf = l_ptr->next_out;
-	if (buf) {
-		struct tipc_msg *msg = buf_msg(buf);
-		u32 next = msg_seqno(msg);
-		u32 first = buf_seqno(l_ptr->first_out);
+	skb_queue_walk_from(outqueue, skb) {
+		msg = buf_msg(skb);
+		next = msg_seqno(msg);
+		first = buf_seqno(skb_peek(outqueue));
 
 		if (mod(next - first) < l_ptr->queue_limit[0]) {
 			msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
 			msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
-			tipc_bearer_send(l_ptr->bearer_id, buf,
-					 &l_ptr->media_addr);
 			if (msg_user(msg) == MSG_BUNDLER)
-				msg_set_type(msg, BUNDLE_CLOSED);
-			l_ptr->next_out = buf->next;
-			return 0;
+				TIPC_SKB_CB(skb)->bundling = false;
+			tipc_bearer_send(l_ptr->bearer_id, skb,
+					 &l_ptr->media_addr);
+			l_ptr->next_out = tipc_skb_queue_next(outqueue, skb);
+		} else {
+			break;
 		}
 	}
-	return 1;
-}
-
-/*
- * push_queue(): push out the unsent messages of a link where
- *               congestion has abated. Node is locked
- */
-void tipc_link_push_queue(struct tipc_link *l_ptr)
-{
-	u32 res;
-
-	do {
-		res = tipc_link_push_packet(l_ptr);
-	} while (!res);
 }
 
 void tipc_link_reset_all(struct tipc_node *node)
@@ -984,20 +960,20 @@ static void link_retransmit_failure(struct tipc_link *l_ptr,
 	}
 }
 
-void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *buf,
+void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *skb,
 			  u32 retransmits)
 {
 	struct tipc_msg *msg;
 
-	if (!buf)
+	if (!skb)
 		return;
 
-	msg = buf_msg(buf);
+	msg = buf_msg(skb);
 
 	/* Detect repeated retransmit failures */
 	if (l_ptr->last_retransmitted == msg_seqno(msg)) {
 		if (++l_ptr->stale_count > 100) {
-			link_retransmit_failure(l_ptr, buf);
+			link_retransmit_failure(l_ptr, skb);
 			return;
 		}
 	} else {
@@ -1005,38 +981,29 @@ void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *buf,
 		l_ptr->stale_count = 1;
 	}
 
-	while (retransmits && (buf != l_ptr->next_out) && buf) {
-		msg = buf_msg(buf);
+	skb_queue_walk_from(&l_ptr->outqueue, skb) {
+		if (!retransmits || skb == l_ptr->next_out)
+			break;
+		msg = buf_msg(skb);
 		msg_set_ack(msg, mod(l_ptr->next_in_no - 1));
 		msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
-		tipc_bearer_send(l_ptr->bearer_id, buf, &l_ptr->media_addr);
-		buf = buf->next;
+		tipc_bearer_send(l_ptr->bearer_id, skb, &l_ptr->media_addr);
 		retransmits--;
 		l_ptr->stats.retransmitted++;
 	}
-
-	l_ptr->retransm_queue_head = l_ptr->retransm_queue_size = 0;
 }
 
-/**
- * link_insert_deferred_queue - insert deferred messages back into receive chain
- */
-static struct sk_buff *link_insert_deferred_queue(struct tipc_link *l_ptr,
-						  struct sk_buff *buf)
+static void link_retrieve_defq(struct tipc_link *link,
+			       struct sk_buff_head *list)
 {
 	u32 seq_no;
 
-	if (l_ptr->oldest_deferred_in == NULL)
-		return buf;
+	if (skb_queue_empty(&link->deferred_queue))
+		return;
 
-	seq_no = buf_seqno(l_ptr->oldest_deferred_in);
-	if (seq_no == mod(l_ptr->next_in_no)) {
-		l_ptr->newest_deferred_in->next = buf;
-		buf = l_ptr->oldest_deferred_in;
-		l_ptr->oldest_deferred_in = NULL;
-		l_ptr->deferred_inqueue_sz = 0;
-	}
-	return buf;
+	seq_no = buf_seqno(skb_peek(&link->deferred_queue));
+	if (seq_no == mod(link->next_in_no))
+		skb_queue_splice_tail_init(&link->deferred_queue, list);
 }
 
 /**
@@ -1096,43 +1063,42 @@ static int link_recv_buf_validate(struct sk_buff *buf)
 
 /**
  * tipc_rcv - process TIPC packets/messages arriving from off-node
- * @head: pointer to message buffer chain
+ * @skb: TIPC packet
  * @b_ptr: pointer to bearer message arrived on
  *
  * Invoked with no locks held.  Bearer pointer must point to a valid bearer
  * structure (i.e. cannot be NULL), but bearer can be inactive.
  */
-void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
+void tipc_rcv(struct sk_buff *skb, struct tipc_bearer *b_ptr)
 {
-	while (head) {
-		struct tipc_node *n_ptr;
-		struct tipc_link *l_ptr;
-		struct sk_buff *crs;
-		struct sk_buff *buf = head;
-		struct tipc_msg *msg;
-		u32 seq_no;
-		u32 ackd;
-		u32 released = 0;
+	struct sk_buff_head head;
+	struct tipc_node *n_ptr;
+	struct tipc_link *l_ptr;
+	struct sk_buff *skb1, *tmp;
+	struct tipc_msg *msg;
+	u32 seq_no;
+	u32 ackd;
+	u32 released;
 
-		head = head->next;
-		buf->next = NULL;
+	skb2list(skb, &head);
 
+	while ((skb = __skb_dequeue(&head))) {
 		/* Ensure message is well-formed */
-		if (unlikely(!link_recv_buf_validate(buf)))
+		if (unlikely(!link_recv_buf_validate(skb)))
 			goto discard;
 
 		/* Ensure message data is a single contiguous unit */
-		if (unlikely(skb_linearize(buf)))
+		if (unlikely(skb_linearize(skb)))
 			goto discard;
 
 		/* Handle arrival of a non-unicast link message */
-		msg = buf_msg(buf);
+		msg = buf_msg(skb);
 
 		if (unlikely(msg_non_seq(msg))) {
 			if (msg_user(msg) ==  LINK_CONFIG)
-				tipc_disc_rcv(buf, b_ptr);
+				tipc_disc_rcv(skb, b_ptr);
 			else
-				tipc_bclink_rcv(buf);
+				tipc_bclink_rcv(skb);
 			continue;
 		}
 
@@ -1171,22 +1137,19 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
 		if (n_ptr->bclink.recv_permitted)
 			tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
 
-		crs = l_ptr->first_out;
-		while ((crs != l_ptr->next_out) &&
-		       less_eq(buf_seqno(crs), ackd)) {
-			struct sk_buff *next = crs->next;
-			kfree_skb(crs);
-			crs = next;
-			released++;
-		}
-		if (released) {
-			l_ptr->first_out = crs;
-			l_ptr->out_queue_size -= released;
+		released = 0;
+		skb_queue_walk_safe(&l_ptr->outqueue, skb1, tmp) {
+			if (skb1 == l_ptr->next_out ||
+			    more(buf_seqno(skb1), ackd))
+				break;
+			 __skb_unlink(skb1, &l_ptr->outqueue);
+			 kfree_skb(skb1);
+			 released = 1;
 		}
 
 		/* Try sending any messages link endpoint has pending */
 		if (unlikely(l_ptr->next_out))
-			tipc_link_push_queue(l_ptr);
+			tipc_link_push_packets(l_ptr);
 
 		if (released && !skb_queue_empty(&l_ptr->waiting_sks)) {
 			link_prepare_wakeup(l_ptr);
@@ -1196,8 +1159,8 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
 		/* Process the incoming packet */
 		if (unlikely(!link_working_working(l_ptr))) {
 			if (msg_user(msg) == LINK_PROTOCOL) {
-				tipc_link_proto_rcv(l_ptr, buf);
-				head = link_insert_deferred_queue(l_ptr, head);
+				tipc_link_proto_rcv(l_ptr, skb);
+				link_retrieve_defq(l_ptr, &head);
 				tipc_node_unlock(n_ptr);
 				continue;
 			}
@@ -1207,8 +1170,7 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
 
 			if (link_working_working(l_ptr)) {
 				/* Re-insert buffer in front of queue */
-				buf->next = head;
-				head = buf;
+				__skb_queue_head(&head, skb);
 				tipc_node_unlock(n_ptr);
 				continue;
 			}
@@ -1217,33 +1179,33 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
 
 		/* Link is now in state WORKING_WORKING */
 		if (unlikely(seq_no != mod(l_ptr->next_in_no))) {
-			link_handle_out_of_seq_msg(l_ptr, buf);
-			head = link_insert_deferred_queue(l_ptr, head);
+			link_handle_out_of_seq_msg(l_ptr, skb);
+			link_retrieve_defq(l_ptr, &head);
 			tipc_node_unlock(n_ptr);
 			continue;
 		}
 		l_ptr->next_in_no++;
-		if (unlikely(l_ptr->oldest_deferred_in))
-			head = link_insert_deferred_queue(l_ptr, head);
+		if (unlikely(!skb_queue_empty(&l_ptr->deferred_queue)))
+			link_retrieve_defq(l_ptr, &head);
 
 		if (unlikely(++l_ptr->unacked_window >= TIPC_MIN_LINK_WIN)) {
 			l_ptr->stats.sent_acks++;
 			tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
 		}
 
-		if (tipc_link_prepare_input(l_ptr, &buf)) {
+		if (tipc_link_prepare_input(l_ptr, &skb)) {
 			tipc_node_unlock(n_ptr);
 			continue;
 		}
 		tipc_node_unlock(n_ptr);
-		msg = buf_msg(buf);
-		if (tipc_link_input(l_ptr, buf) != 0)
+
+		if (tipc_link_input(l_ptr, skb) != 0)
 			goto discard;
 		continue;
 unlock_discard:
 		tipc_node_unlock(n_ptr);
 discard:
-		kfree_skb(buf);
+		kfree_skb(skb);
 	}
 }
 
@@ -1326,48 +1288,37 @@ static int tipc_link_input(struct tipc_link *l, struct sk_buff *buf)
  *
  * Returns increase in queue length (i.e. 0 or 1)
  */
-u32 tipc_link_defer_pkt(struct sk_buff **head, struct sk_buff **tail,
-			struct sk_buff *buf)
+u32 tipc_link_defer_pkt(struct sk_buff_head *list, struct sk_buff *skb)
 {
-	struct sk_buff *queue_buf;
-	struct sk_buff **prev;
-	u32 seq_no = buf_seqno(buf);
-
-	buf->next = NULL;
+	struct sk_buff *skb1;
+	u32 seq_no = buf_seqno(skb);
 
 	/* Empty queue ? */
-	if (*head == NULL) {
-		*head = *tail = buf;
+	if (skb_queue_empty(list)) {
+		__skb_queue_tail(list, skb);
 		return 1;
 	}
 
 	/* Last ? */
-	if (less(buf_seqno(*tail), seq_no)) {
-		(*tail)->next = buf;
-		*tail = buf;
+	if (less(buf_seqno(skb_peek_tail(list)), seq_no)) {
+		__skb_queue_tail(list, skb);
 		return 1;
 	}
 
 	/* Locate insertion point in queue, then insert; discard if duplicate */
-	prev = head;
-	queue_buf = *head;
-	for (;;) {
-		u32 curr_seqno = buf_seqno(queue_buf);
+	skb_queue_walk(list, skb1) {
+		u32 curr_seqno = buf_seqno(skb1);
 
 		if (seq_no == curr_seqno) {
-			kfree_skb(buf);
+			kfree_skb(skb);
 			return 0;
 		}
 
 		if (less(seq_no, curr_seqno))
 			break;
-
-		prev = &queue_buf->next;
-		queue_buf = queue_buf->next;
 	}
 
-	buf->next = queue_buf;
-	*prev = buf;
+	__skb_queue_before(list, skb1, skb);
 	return 1;
 }
 
@@ -1397,15 +1348,14 @@ static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
 		return;
 	}
 
-	if (tipc_link_defer_pkt(&l_ptr->oldest_deferred_in,
-				&l_ptr->newest_deferred_in, buf)) {
-		l_ptr->deferred_inqueue_sz++;
+	if (tipc_link_defer_pkt(&l_ptr->deferred_queue, buf)) {
 		l_ptr->stats.deferred_recv++;
 		TIPC_SKB_CB(buf)->deferred = true;
-		if ((l_ptr->deferred_inqueue_sz % 16) == 1)
+		if ((skb_queue_len(&l_ptr->deferred_queue) % 16) == 1)
 			tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
-	} else
+	} else {
 		l_ptr->stats.duplicates++;
+	}
 }
 
 /*
@@ -1419,12 +1369,6 @@ void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg,
 	u32 msg_size = sizeof(l_ptr->proto_msg);
 	int r_flag;
 
-	/* Discard any previous message that was deferred due to congestion */
-	if (l_ptr->proto_msg_queue) {
-		kfree_skb(l_ptr->proto_msg_queue);
-		l_ptr->proto_msg_queue = NULL;
-	}
-
 	/* Don't send protocol message during link changeover */
 	if (l_ptr->exp_msg_count)
 		return;
@@ -1447,8 +1391,8 @@ void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg,
 		if (l_ptr->next_out)
 			next_sent = buf_seqno(l_ptr->next_out);
 		msg_set_next_sent(msg, next_sent);
-		if (l_ptr->oldest_deferred_in) {
-			u32 rec = buf_seqno(l_ptr->oldest_deferred_in);
+		if (!skb_queue_empty(&l_ptr->deferred_queue)) {
+			u32 rec = buf_seqno(skb_peek(&l_ptr->deferred_queue));
 			gap = mod(rec - mod(l_ptr->next_in_no));
 		}
 		msg_set_seq_gap(msg, gap);
@@ -1636,7 +1580,7 @@ static void tipc_link_proto_rcv(struct tipc_link *l_ptr, struct sk_buff *buf)
 		}
 		if (msg_seq_gap(msg)) {
 			l_ptr->stats.recv_nacks++;
-			tipc_link_retransmit(l_ptr, l_ptr->first_out,
+			tipc_link_retransmit(l_ptr, skb_peek(&l_ptr->outqueue),
 					     msg_seq_gap(msg));
 		}
 		break;
@@ -1655,7 +1599,7 @@ static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr,
 				  u32 selector)
 {
 	struct tipc_link *tunnel;
-	struct sk_buff *buf;
+	struct sk_buff *skb;
 	u32 length = msg_size(msg);
 
 	tunnel = l_ptr->owner->active_links[selector & 1];
@@ -1664,14 +1608,14 @@ static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr,
 		return;
 	}
 	msg_set_size(tunnel_hdr, length + INT_H_SIZE);
-	buf = tipc_buf_acquire(length + INT_H_SIZE);
-	if (!buf) {
+	skb = tipc_buf_acquire(length + INT_H_SIZE);
+	if (!skb) {
 		pr_warn("%sunable to send tunnel msg\n", link_co_err);
 		return;
 	}
-	skb_copy_to_linear_data(buf, tunnel_hdr, INT_H_SIZE);
-	skb_copy_to_linear_data_offset(buf, INT_H_SIZE, msg, length);
-	__tipc_link_xmit(tunnel, buf);
+	skb_copy_to_linear_data(skb, tunnel_hdr, INT_H_SIZE);
+	skb_copy_to_linear_data_offset(skb, INT_H_SIZE, msg, length);
+	__tipc_link_xmit_skb(tunnel, skb);
 }
 
 
@@ -1683,10 +1627,10 @@ static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr,
  */
 void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
 {
-	u32 msgcount = l_ptr->out_queue_size;
-	struct sk_buff *crs = l_ptr->first_out;
+	u32 msgcount = skb_queue_len(&l_ptr->outqueue);
 	struct tipc_link *tunnel = l_ptr->owner->active_links[0];
 	struct tipc_msg tunnel_hdr;
+	struct sk_buff *skb;
 	int split_bundles;
 
 	if (!tunnel)
@@ -1697,14 +1641,12 @@ void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
 	msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
 	msg_set_msgcnt(&tunnel_hdr, msgcount);
 
-	if (!l_ptr->first_out) {
-		struct sk_buff *buf;
-
-		buf = tipc_buf_acquire(INT_H_SIZE);
-		if (buf) {
-			skb_copy_to_linear_data(buf, &tunnel_hdr, INT_H_SIZE);
+	if (skb_queue_empty(&l_ptr->outqueue)) {
+		skb = tipc_buf_acquire(INT_H_SIZE);
+		if (skb) {
+			skb_copy_to_linear_data(skb, &tunnel_hdr, INT_H_SIZE);
 			msg_set_size(&tunnel_hdr, INT_H_SIZE);
-			__tipc_link_xmit(tunnel, buf);
+			__tipc_link_xmit_skb(tunnel, skb);
 		} else {
 			pr_warn("%sunable to send changeover msg\n",
 				link_co_err);
@@ -1715,8 +1657,8 @@ void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
 	split_bundles = (l_ptr->owner->active_links[0] !=
 			 l_ptr->owner->active_links[1]);
 
-	while (crs) {
-		struct tipc_msg *msg = buf_msg(crs);
+	skb_queue_walk(&l_ptr->outqueue, skb) {
+		struct tipc_msg *msg = buf_msg(skb);
 
 		if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
 			struct tipc_msg *m = msg_get_wrapped(msg);
@@ -1734,7 +1676,6 @@ void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
 			tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, msg,
 					      msg_link_selector(msg));
 		}
-		crs = crs->next;
 	}
 }
 
@@ -1750,17 +1691,16 @@ void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
 void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr,
 			      struct tipc_link *tunnel)
 {
-	struct sk_buff *iter;
+	struct sk_buff *skb;
 	struct tipc_msg tunnel_hdr;
 
 	tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
 		 DUPLICATE_MSG, INT_H_SIZE, l_ptr->addr);
-	msg_set_msgcnt(&tunnel_hdr, l_ptr->out_queue_size);
+	msg_set_msgcnt(&tunnel_hdr, skb_queue_len(&l_ptr->outqueue));
 	msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
-	iter = l_ptr->first_out;
-	while (iter) {
-		struct sk_buff *outbuf;
-		struct tipc_msg *msg = buf_msg(iter);
+	skb_queue_walk(&l_ptr->outqueue, skb) {
+		struct sk_buff *outskb;
+		struct tipc_msg *msg = buf_msg(skb);
 		u32 length = msg_size(msg);
 
 		if (msg_user(msg) == MSG_BUNDLER)
@@ -1768,19 +1708,18 @@ void tipc_link_dup_queue_xmit(struct tipc_link *l_ptr,
 		msg_set_ack(msg, mod(l_ptr->next_in_no - 1));	/* Update */
 		msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
 		msg_set_size(&tunnel_hdr, length + INT_H_SIZE);
-		outbuf = tipc_buf_acquire(length + INT_H_SIZE);
-		if (outbuf == NULL) {
+		outskb = tipc_buf_acquire(length + INT_H_SIZE);
+		if (outskb == NULL) {
 			pr_warn("%sunable to send duplicate msg\n",
 				link_co_err);
 			return;
 		}
-		skb_copy_to_linear_data(outbuf, &tunnel_hdr, INT_H_SIZE);
-		skb_copy_to_linear_data_offset(outbuf, INT_H_SIZE, iter->data,
+		skb_copy_to_linear_data(outskb, &tunnel_hdr, INT_H_SIZE);
+		skb_copy_to_linear_data_offset(outskb, INT_H_SIZE, skb->data,
 					       length);
-		__tipc_link_xmit(tunnel, outbuf);
+		__tipc_link_xmit_skb(tunnel, outskb);
 		if (!tipc_link_is_up(l_ptr))
 			return;
-		iter = iter->next;
 	}
 }
 
@@ -2375,3 +2314,435 @@ static void link_print(struct tipc_link *l_ptr, const char *str)
 	else
 		pr_cont("\n");
 }
+
+/* Parse and validate nested (link) properties valid for media, bearer and link
+ */
+int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
+{
+	int err;
+
+	err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
+			       tipc_nl_prop_policy);
+	if (err)
+		return err;
+
+	if (props[TIPC_NLA_PROP_PRIO]) {
+		u32 prio;
+
+		prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
+		if (prio > TIPC_MAX_LINK_PRI)
+			return -EINVAL;
+	}
+
+	if (props[TIPC_NLA_PROP_TOL]) {
+		u32 tol;
+
+		tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
+		if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
+			return -EINVAL;
+	}
+
+	if (props[TIPC_NLA_PROP_WIN]) {
+		u32 win;
+
+		win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
+		if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info)
+{
+	int err;
+	int res = 0;
+	int bearer_id;
+	char *name;
+	struct tipc_link *link;
+	struct tipc_node *node;
+	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
+
+	if (!info->attrs[TIPC_NLA_LINK])
+		return -EINVAL;
+
+	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
+			       info->attrs[TIPC_NLA_LINK],
+			       tipc_nl_link_policy);
+	if (err)
+		return err;
+
+	if (!attrs[TIPC_NLA_LINK_NAME])
+		return -EINVAL;
+
+	name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
+
+	node = tipc_link_find_owner(name, &bearer_id);
+	if (!node)
+		return -EINVAL;
+
+	tipc_node_lock(node);
+
+	link = node->links[bearer_id];
+	if (!link) {
+		res = -EINVAL;
+		goto out;
+	}
+
+	if (attrs[TIPC_NLA_LINK_PROP]) {
+		struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
+
+		err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
+					      props);
+		if (err) {
+			res = err;
+			goto out;
+		}
+
+		if (props[TIPC_NLA_PROP_TOL]) {
+			u32 tol;
+
+			tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
+			link_set_supervision_props(link, tol);
+			tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0, 0);
+		}
+		if (props[TIPC_NLA_PROP_PRIO]) {
+			u32 prio;
+
+			prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
+			link->priority = prio;
+			tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio, 0);
+		}
+		if (props[TIPC_NLA_PROP_WIN]) {
+			u32 win;
+
+			win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
+			tipc_link_set_queue_limits(link, win);
+		}
+	}
+
+out:
+	tipc_node_unlock(node);
+
+	return res;
+}
+
+static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
+{
+	int i;
+	struct nlattr *stats;
+
+	struct nla_map {
+		u32 key;
+		u32 val;
+	};
+
+	struct nla_map map[] = {
+		{TIPC_NLA_STATS_RX_INFO, s->recv_info},
+		{TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
+		{TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
+		{TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
+		{TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
+		{TIPC_NLA_STATS_TX_INFO, s->sent_info},
+		{TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
+		{TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
+		{TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
+		{TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
+		{TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
+			s->msg_length_counts : 1},
+		{TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
+		{TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
+		{TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
+		{TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
+		{TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
+		{TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
+		{TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
+		{TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
+		{TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
+		{TIPC_NLA_STATS_RX_STATES, s->recv_states},
+		{TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
+		{TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
+		{TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
+		{TIPC_NLA_STATS_TX_STATES, s->sent_states},
+		{TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
+		{TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
+		{TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
+		{TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
+		{TIPC_NLA_STATS_DUPLICATES, s->duplicates},
+		{TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
+		{TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
+		{TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
+			(s->accu_queue_sz / s->queue_sz_counts) : 0}
+	};
+
+	stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
+	if (!stats)
+		return -EMSGSIZE;
+
+	for (i = 0; i <  ARRAY_SIZE(map); i++)
+		if (nla_put_u32(skb, map[i].key, map[i].val))
+			goto msg_full;
+
+	nla_nest_end(skb, stats);
+
+	return 0;
+msg_full:
+	nla_nest_cancel(skb, stats);
+
+	return -EMSGSIZE;
+}
+
+/* Caller should hold appropriate locks to protect the link */
+static int __tipc_nl_add_link(struct tipc_nl_msg *msg, struct tipc_link *link)
+{
+	int err;
+	void *hdr;
+	struct nlattr *attrs;
+	struct nlattr *prop;
+
+	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_v2_family,
+			  NLM_F_MULTI, TIPC_NL_LINK_GET);
+	if (!hdr)
+		return -EMSGSIZE;
+
+	attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
+	if (!attrs)
+		goto msg_full;
+
+	if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
+		goto attr_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
+			tipc_cluster_mask(tipc_own_addr)))
+		goto attr_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->max_pkt))
+		goto attr_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->next_in_no))
+		goto attr_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->next_out_no))
+		goto attr_msg_full;
+
+	if (tipc_link_is_up(link))
+		if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
+			goto attr_msg_full;
+	if (tipc_link_is_active(link))
+		if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
+			goto attr_msg_full;
+
+	prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
+	if (!prop)
+		goto attr_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
+		goto prop_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
+		goto prop_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
+			link->queue_limit[TIPC_LOW_IMPORTANCE]))
+		goto prop_msg_full;
+	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
+		goto prop_msg_full;
+	nla_nest_end(msg->skb, prop);
+
+	err = __tipc_nl_add_stats(msg->skb, &link->stats);
+	if (err)
+		goto attr_msg_full;
+
+	nla_nest_end(msg->skb, attrs);
+	genlmsg_end(msg->skb, hdr);
+
+	return 0;
+
+prop_msg_full:
+	nla_nest_cancel(msg->skb, prop);
+attr_msg_full:
+	nla_nest_cancel(msg->skb, attrs);
+msg_full:
+	genlmsg_cancel(msg->skb, hdr);
+
+	return -EMSGSIZE;
+}
+
+/* Caller should hold node lock  */
+static int __tipc_nl_add_node_links(struct tipc_nl_msg *msg,
+				    struct tipc_node *node,
+				    u32 *prev_link)
+{
+	u32 i;
+	int err;
+
+	for (i = *prev_link; i < MAX_BEARERS; i++) {
+		*prev_link = i;
+
+		if (!node->links[i])
+			continue;
+
+		err = __tipc_nl_add_link(msg, node->links[i]);
+		if (err)
+			return err;
+	}
+	*prev_link = 0;
+
+	return 0;
+}
+
+int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct tipc_node *node;
+	struct tipc_nl_msg msg;
+	u32 prev_node = cb->args[0];
+	u32 prev_link = cb->args[1];
+	int done = cb->args[2];
+	int err;
+
+	if (done)
+		return 0;
+
+	msg.skb = skb;
+	msg.portid = NETLINK_CB(cb->skb).portid;
+	msg.seq = cb->nlh->nlmsg_seq;
+
+	rcu_read_lock();
+
+	if (prev_node) {
+		node = tipc_node_find(prev_node);
+		if (!node) {
+			/* We never set seq or call nl_dump_check_consistent()
+			 * this means that setting prev_seq here will cause the
+			 * consistence check to fail in the netlink callback
+			 * handler. Resulting in the last NLMSG_DONE message
+			 * having the NLM_F_DUMP_INTR flag set.
+			 */
+			cb->prev_seq = 1;
+			goto out;
+		}
+
+		list_for_each_entry_continue_rcu(node, &tipc_node_list, list) {
+			tipc_node_lock(node);
+			err = __tipc_nl_add_node_links(&msg, node, &prev_link);
+			tipc_node_unlock(node);
+			if (err)
+				goto out;
+
+			prev_node = node->addr;
+		}
+	} else {
+		err = tipc_nl_add_bc_link(&msg);
+		if (err)
+			goto out;
+
+		list_for_each_entry_rcu(node, &tipc_node_list, list) {
+			tipc_node_lock(node);
+			err = __tipc_nl_add_node_links(&msg, node, &prev_link);
+			tipc_node_unlock(node);
+			if (err)
+				goto out;
+
+			prev_node = node->addr;
+		}
+	}
+	done = 1;
+out:
+	rcu_read_unlock();
+
+	cb->args[0] = prev_node;
+	cb->args[1] = prev_link;
+	cb->args[2] = done;
+
+	return skb->len;
+}
+
+int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info)
+{
+	struct sk_buff *ans_skb;
+	struct tipc_nl_msg msg;
+	struct tipc_link *link;
+	struct tipc_node *node;
+	char *name;
+	int bearer_id;
+	int err;
+
+	if (!info->attrs[TIPC_NLA_LINK_NAME])
+		return -EINVAL;
+
+	name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]);
+	node = tipc_link_find_owner(name, &bearer_id);
+	if (!node)
+		return -EINVAL;
+
+	ans_skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!ans_skb)
+		return -ENOMEM;
+
+	msg.skb = ans_skb;
+	msg.portid = info->snd_portid;
+	msg.seq = info->snd_seq;
+
+	tipc_node_lock(node);
+	link = node->links[bearer_id];
+	if (!link) {
+		err = -EINVAL;
+		goto err_out;
+	}
+
+	err = __tipc_nl_add_link(&msg, link);
+	if (err)
+		goto err_out;
+
+	tipc_node_unlock(node);
+
+	return genlmsg_reply(ans_skb, info);
+
+err_out:
+	tipc_node_unlock(node);
+	nlmsg_free(ans_skb);
+
+	return err;
+}
+
+int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
+{
+	int err;
+	char *link_name;
+	unsigned int bearer_id;
+	struct tipc_link *link;
+	struct tipc_node *node;
+	struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
+
+	if (!info->attrs[TIPC_NLA_LINK])
+		return -EINVAL;
+
+	err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
+			       info->attrs[TIPC_NLA_LINK],
+			       tipc_nl_link_policy);
+	if (err)
+		return err;
+
+	if (!attrs[TIPC_NLA_LINK_NAME])
+		return -EINVAL;
+
+	link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
+
+	if (strcmp(link_name, tipc_bclink_name) == 0) {
+		err = tipc_bclink_reset_stats();
+		if (err)
+			return err;
+		return 0;
+	}
+
+	node = tipc_link_find_owner(link_name, &bearer_id);
+	if (!node)
+		return -EINVAL;
+
+	tipc_node_lock(node);
+
+	link = node->links[bearer_id];
+	if (!link) {
+		tipc_node_unlock(node);
+		return -EINVAL;
+	}
+
+	link_reset_statistics(link);
+
+	tipc_node_unlock(node);
+
+	return 0;
+}