Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into sh-latest

14 files changed, 320 insertions, 309 deletions

diff --git a/net/tipc/addr.h b/net/tipc/addr.h
index 8971aba99ae..e4f35afe320 100644
--- a/net/tipc/addr.h
+++ b/net/tipc/addr.h
@@ -37,14 +37,17 @@
 #ifndef _TIPC_ADDR_H
 #define _TIPC_ADDR_H
 
+#define TIPC_ZONE_MASK		0xff000000u
+#define TIPC_CLUSTER_MASK	0xfffff000u
+
 static inline u32 tipc_zone_mask(u32 addr)
 {
-	return addr & 0xff000000u;
+	return addr & TIPC_ZONE_MASK;
 }
 
 static inline u32 tipc_cluster_mask(u32 addr)
 {
-	return addr & 0xfffff000u;
+	return addr & TIPC_CLUSTER_MASK;
 }
 
 static inline int in_own_cluster(u32 addr)
diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c
index 7dc1dc7151e..fa68d1e9ff4 100644
--- a/net/tipc/bcast.c
+++ b/net/tipc/bcast.c
@@ -44,13 +44,6 @@
 
 #define BCLINK_WIN_DEFAULT 20		/* bcast link window size (default) */
 
-/*
- * Loss rate for incoming broadcast frames; used to test retransmission code.
- * Set to N to cause every N'th frame to be discarded; 0 => don't discard any.
- */
-
-#define TIPC_BCAST_LOSS_RATE 0
-
 /**
  * struct bcbearer_pair - a pair of bearers used by broadcast link
  * @primary: pointer to primary bearer
@@ -414,9 +407,7 @@ int tipc_bclink_send_msg(struct sk_buff *buf)
 	spin_lock_bh(&bc_lock);
 
 	res = tipc_link_send_buf(bcl, buf);
-	if (unlikely(res == -ELINKCONG))
-		buf_discard(buf);
-	else
+	if (likely(res > 0))
 		bclink_set_last_sent();
 
 	bcl->stats.queue_sz_counts++;
@@ -434,9 +425,6 @@ int tipc_bclink_send_msg(struct sk_buff *buf)
 
 void tipc_bclink_recv_pkt(struct sk_buff *buf)
 {
-#if (TIPC_BCAST_LOSS_RATE)
-	static int rx_count;
-#endif
 	struct tipc_msg *msg = buf_msg(buf);
 	struct tipc_node *node = tipc_node_find(msg_prevnode(msg));
 	u32 next_in;
@@ -470,14 +458,6 @@ void tipc_bclink_recv_pkt(struct sk_buff *buf)
 		return;
 	}
 
-#if (TIPC_BCAST_LOSS_RATE)
-	if (++rx_count == TIPC_BCAST_LOSS_RATE) {
-		rx_count = 0;
-		buf_discard(buf);
-		return;
-	}
-#endif
-
 	tipc_node_lock(node);
 receive:
 	deferred = node->bclink.deferred_head;
diff --git a/net/tipc/bearer.c b/net/tipc/bearer.c
index 411719feb80..85209eadfae 100644
--- a/net/tipc/bearer.c
+++ b/net/tipc/bearer.c
@@ -46,6 +46,8 @@ static u32 media_count;
 
 struct tipc_bearer tipc_bearers[MAX_BEARERS];
 
+static void bearer_disable(struct tipc_bearer *b_ptr);
+
 /**
  * media_name_valid - validate media name
  *
@@ -342,15 +344,15 @@ struct sk_buff *tipc_bearer_get_names(void)
 void tipc_bearer_add_dest(struct tipc_bearer *b_ptr, u32 dest)
 {
 	tipc_nmap_add(&b_ptr->nodes, dest);
-	tipc_disc_update_link_req(b_ptr->link_req);
 	tipc_bcbearer_sort();
+	tipc_disc_add_dest(b_ptr->link_req);
 }
 
 void tipc_bearer_remove_dest(struct tipc_bearer *b_ptr, u32 dest)
 {
 	tipc_nmap_remove(&b_ptr->nodes, dest);
-	tipc_disc_update_link_req(b_ptr->link_req);
 	tipc_bcbearer_sort();
+	tipc_disc_remove_dest(b_ptr->link_req);
 }
 
 /*
@@ -493,8 +495,15 @@ int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority)
 		warn("Bearer <%s> rejected, illegal name\n", name);
 		return -EINVAL;
 	}
-	if (!tipc_addr_domain_valid(disc_domain) ||
-	    !tipc_in_scope(disc_domain, tipc_own_addr)) {
+	if (tipc_addr_domain_valid(disc_domain) &&
+	    (disc_domain != tipc_own_addr)) {
+		if (tipc_in_scope(disc_domain, tipc_own_addr)) {
+			disc_domain = tipc_own_addr & TIPC_CLUSTER_MASK;
+			res = 0;   /* accept any node in own cluster */
+		} else if (in_own_cluster(disc_domain))
+			res = 0;   /* accept specified node in own cluster */
+	}
+	if (res) {
 		warn("Bearer <%s> rejected, illegal discovery domain\n", name);
 		return -EINVAL;
 	}
@@ -511,7 +520,7 @@ int tipc_enable_bearer(const char *name, u32 disc_domain, u32 priority)
 	if (!m_ptr) {
 		warn("Bearer <%s> rejected, media <%s> not registered\n", name,
 		     b_name.media_name);
-		goto failed;
+		goto exit;
 	}
 
 	if (priority == TIPC_MEDIA_LINK_PRI)
@@ -527,14 +536,14 @@ restart:
 		}
 		if (!strcmp(name, tipc_bearers[i].name)) {
 			warn("Bearer <%s> rejected, already enabled\n", name);
-			goto failed;
+			goto exit;
 		}
 		if ((tipc_bearers[i].priority == priority) &&
 		    (++with_this_prio > 2)) {
 			if (priority-- == 0) {
 				warn("Bearer <%s> rejected, duplicate priority\n",
 				     name);
-				goto failed;
+				goto exit;
 			}
 			warn("Bearer <%s> priority adjustment required %u->%u\n",
 			     name, priority + 1, priority);
@@ -544,7 +553,7 @@ restart:
 	if (bearer_id >= MAX_BEARERS) {
 		warn("Bearer <%s> rejected, bearer limit reached (%u)\n",
 		     name, MAX_BEARERS);
-		goto failed;
+		goto exit;
 	}
 
 	b_ptr = &tipc_bearers[bearer_id];
@@ -552,7 +561,7 @@ restart:
 	res = m_ptr->enable_bearer(b_ptr);
 	if (res) {
 		warn("Bearer <%s> rejected, enable failure (%d)\n", name, -res);
-		goto failed;
+		goto exit;
 	}
 
 	b_ptr->identity = bearer_id;
@@ -562,14 +571,18 @@ restart:
 	b_ptr->priority = priority;
 	INIT_LIST_HEAD(&b_ptr->cong_links);
 	INIT_LIST_HEAD(&b_ptr->links);
-	b_ptr->link_req = tipc_disc_init_link_req(b_ptr, &m_ptr->bcast_addr,
-						  disc_domain);
 	spin_lock_init(&b_ptr->lock);
-	write_unlock_bh(&tipc_net_lock);
+
+	res = tipc_disc_create(b_ptr, &m_ptr->bcast_addr, disc_domain);
+	if (res) {
+		bearer_disable(b_ptr);
+		warn("Bearer <%s> rejected, discovery object creation failed\n",
+		     name);
+		goto exit;
+	}
 	info("Enabled bearer <%s>, discovery domain %s, priority %u\n",
 	     name, tipc_addr_string_fill(addr_string, disc_domain), priority);
-	return 0;
-failed:
+exit:
 	write_unlock_bh(&tipc_net_lock);
 	return res;
 }
@@ -620,14 +633,14 @@ static void bearer_disable(struct tipc_bearer *b_ptr)
 	struct link *temp_l_ptr;
 
 	info("Disabling bearer <%s>\n", b_ptr->name);
-	tipc_disc_stop_link_req(b_ptr->link_req);
 	spin_lock_bh(&b_ptr->lock);
-	b_ptr->link_req = NULL;
 	b_ptr->blocked = 1;
 	b_ptr->media->disable_bearer(b_ptr);
 	list_for_each_entry_safe(l_ptr, temp_l_ptr, &b_ptr->links, link_list) {
 		tipc_link_delete(l_ptr);
 	}
+	if (b_ptr->link_req)
+		tipc_disc_delete(b_ptr->link_req);
 	spin_unlock_bh(&b_ptr->lock);
 	memset(b_ptr, 0, sizeof(struct tipc_bearer));
 }
diff --git a/net/tipc/core.c b/net/tipc/core.c
index c9a73e7763f..943b6af8426 100644
--- a/net/tipc/core.c
+++ b/net/tipc/core.c
@@ -179,8 +179,7 @@ static int __init tipc_init(void)
 	if (tipc_log_resize(CONFIG_TIPC_LOG) != 0)
 		warn("Unable to create log buffer\n");
 
-	info("Activated (version " TIPC_MOD_VER
-	     " compiled " __DATE__ " " __TIME__ ")\n");
+	info("Activated (version " TIPC_MOD_VER ")\n");
 
 	tipc_own_addr = 0;
 	tipc_remote_management = 1;
diff --git a/net/tipc/discover.c b/net/tipc/discover.c
index 491eff56b9d..0987933155b 100644
--- a/net/tipc/discover.c
+++ b/net/tipc/discover.c
@@ -39,19 +39,17 @@
 #include "discover.h"
 
 #define TIPC_LINK_REQ_INIT	125	/* min delay during bearer start up */
-#define TIPC_LINK_REQ_FAST	2000	/* normal delay if bearer has no links */
-#define TIPC_LINK_REQ_SLOW	600000	/* normal delay if bearer has links */
-
-/*
- * TODO: Most of the inter-cluster setup stuff should be
- * rewritten, and be made conformant with specification.
- */
+#define TIPC_LINK_REQ_FAST	1000	/* max delay if bearer has no links */
+#define TIPC_LINK_REQ_SLOW	60000	/* max delay if bearer has links */
+#define TIPC_LINK_REQ_INACTIVE	0xffffffff /* indicates no timer in use */
 
 
 /**
  * struct link_req - information about an ongoing link setup request
  * @bearer: bearer issuing requests
  * @dest: destination address for request messages
+ * @domain: network domain to which links can be established
+ * @num_nodes: number of nodes currently discovered (i.e. with an active link)
  * @buf: request message to be (repeatedly) sent
  * @timer: timer governing period between requests
  * @timer_intv: current interval between requests (in ms)
@@ -59,6 +57,8 @@
 struct link_req {
 	struct tipc_bearer *bearer;
 	struct tipc_media_addr dest;
+	u32 domain;
+	int num_nodes;
 	struct sk_buff *buf;
 	struct timer_list timer;
 	unsigned int timer_intv;
@@ -147,7 +147,7 @@ void tipc_disc_recv_msg(struct sk_buff *buf, struct tipc_bearer *b_ptr)
 	}
 	if (!tipc_in_scope(dest, tipc_own_addr))
 		return;
-	if (!in_own_cluster(orig))
+	if (!tipc_in_scope(b_ptr->link_req->domain, orig))
 		return;
 
 	/* Locate structure corresponding to requesting node */
@@ -214,44 +214,54 @@ void tipc_disc_recv_msg(struct sk_buff *buf, struct tipc_bearer *b_ptr)
 }
 
 /**
- * tipc_disc_stop_link_req - stop sending periodic link setup requests
+ * disc_update - update frequency of periodic link setup requests
  * @req: ptr to link request structure
+ *
+ * Reinitiates discovery process if discovery object has no associated nodes
+ * and is either not currently searching or is searching at a slow rate
  */
 
-void tipc_disc_stop_link_req(struct link_req *req)
+static void disc_update(struct link_req *req)
 {
-	if (!req)
-		return;
+	if (!req->num_nodes) {
+		if ((req->timer_intv == TIPC_LINK_REQ_INACTIVE) ||
+		    (req->timer_intv > TIPC_LINK_REQ_FAST)) {
+			req->timer_intv = TIPC_LINK_REQ_INIT;
+			k_start_timer(&req->timer, req->timer_intv);
+		}
+	}
+}
 
-	k_cancel_timer(&req->timer);
-	k_term_timer(&req->timer);
-	buf_discard(req->buf);
-	kfree(req);
+/**
+ * tipc_disc_add_dest - increment set of discovered nodes
+ * @req: ptr to link request structure
+ */
+
+void tipc_disc_add_dest(struct link_req *req)
+{
+	req->num_nodes++;
 }
 
 /**
- * tipc_disc_update_link_req - update frequency of periodic link setup requests
+ * tipc_disc_remove_dest - decrement set of discovered nodes
  * @req: ptr to link request structure
  */
 
-void tipc_disc_update_link_req(struct link_req *req)
+void tipc_disc_remove_dest(struct link_req *req)
 {
-	if (!req)
-		return;
+	req->num_nodes--;
+	disc_update(req);
+}
 
-	if (req->timer_intv == TIPC_LINK_REQ_SLOW) {
-		if (!req->bearer->nodes.count) {
-			req->timer_intv = TIPC_LINK_REQ_FAST;
-			k_start_timer(&req->timer, req->timer_intv);
-		}
-	} else if (req->timer_intv == TIPC_LINK_REQ_FAST) {
-		if (req->bearer->nodes.count) {
-			req->timer_intv = TIPC_LINK_REQ_SLOW;
-			k_start_timer(&req->timer, req->timer_intv);
-		}
-	} else {
-		/* leave timer "as is" if haven't yet reached a "normal" rate */
-	}
+/**
+ * disc_send_msg - send link setup request message
+ * @req: ptr to link request structure
+ */
+
+static void disc_send_msg(struct link_req *req)
+{
+	if (!req->bearer->blocked)
+		tipc_bearer_send(req->bearer, req->buf, &req->dest);
 }
 
 /**
@@ -263,56 +273,86 @@ void tipc_disc_update_link_req(struct link_req *req)
 
 static void disc_timeout(struct link_req *req)
 {
+	int max_delay;
+
 	spin_lock_bh(&req->bearer->lock);
 
-	req->bearer->media->send_msg(req->buf, req->bearer, &req->dest);
-
-	if ((req->timer_intv == TIPC_LINK_REQ_SLOW) ||
-	    (req->timer_intv == TIPC_LINK_REQ_FAST)) {
-		/* leave timer interval "as is" if already at a "normal" rate */
-	} else {
-		req->timer_intv *= 2;
-		if (req->timer_intv > TIPC_LINK_REQ_FAST)
-			req->timer_intv = TIPC_LINK_REQ_FAST;
-		if ((req->timer_intv == TIPC_LINK_REQ_FAST) &&
-		    (req->bearer->nodes.count))
-			req->timer_intv = TIPC_LINK_REQ_SLOW;
+	/* Stop searching if only desired node has been found */
+
+	if (tipc_node(req->domain) && req->num_nodes) {
+		req->timer_intv = TIPC_LINK_REQ_INACTIVE;
+		goto exit;
 	}
-	k_start_timer(&req->timer, req->timer_intv);
 
+	/*
+	 * Send discovery message, then update discovery timer
+	 *
+	 * Keep doubling time between requests until limit is reached;
+	 * hold at fast polling rate if don't have any associated nodes,
+	 * otherwise hold at slow polling rate
+	 */
+
+	disc_send_msg(req);
+
+	req->timer_intv *= 2;
+	if (req->num_nodes)
+		max_delay = TIPC_LINK_REQ_SLOW;
+	else
+		max_delay = TIPC_LINK_REQ_FAST;
+	if (req->timer_intv > max_delay)
+		req->timer_intv = max_delay;
+
+	k_start_timer(&req->timer, req->timer_intv);
+exit:
 	spin_unlock_bh(&req->bearer->lock);
 }
 
 /**
- * tipc_disc_init_link_req - start sending periodic link setup requests
+ * tipc_disc_create - create object to send periodic link setup requests
  * @b_ptr: ptr to bearer issuing requests
  * @dest: destination address for request messages
- * @dest_domain: network domain of node(s) which should respond to message
+ * @dest_domain: network domain to which links can be established
  *
- * Returns pointer to link request structure, or NULL if unable to create.
+ * Returns 0 if successful, otherwise -errno.
  */
 
-struct link_req *tipc_disc_init_link_req(struct tipc_bearer *b_ptr,
-					 const struct tipc_media_addr *dest,
-					 u32 dest_domain)
+int tipc_disc_create(struct tipc_bearer *b_ptr,
+		     struct tipc_media_addr *dest, u32 dest_domain)
 {
 	struct link_req *req;
 
 	req = kmalloc(sizeof(*req), GFP_ATOMIC);
 	if (!req)
-		return NULL;
+		return -ENOMEM;
 
 	req->buf = tipc_disc_init_msg(DSC_REQ_MSG, dest_domain, b_ptr);
 	if (!req->buf) {
 		kfree(req);
-		return NULL;
+		return -ENOMSG;
 	}
 
 	memcpy(&req->dest, dest, sizeof(*dest));
 	req->bearer = b_ptr;
+	req->domain = dest_domain;
+	req->num_nodes = 0;
 	req->timer_intv = TIPC_LINK_REQ_INIT;
 	k_init_timer(&req->timer, (Handler)disc_timeout, (unsigned long)req);
 	k_start_timer(&req->timer, req->timer_intv);
-	return req;
+	b_ptr->link_req = req;
+	disc_send_msg(req);
+	return 0;
+}
+
+/**
+ * tipc_disc_delete - destroy object sending periodic link setup requests
+ * @req: ptr to link request structure
+ */
+
+void tipc_disc_delete(struct link_req *req)
+{
+	k_cancel_timer(&req->timer);
+	k_term_timer(&req->timer);
+	buf_discard(req->buf);
+	kfree(req);
 }
 
diff --git a/net/tipc/discover.h b/net/tipc/discover.h
index e48a167e47b..a3af595b86c 100644
--- a/net/tipc/discover.h
+++ b/net/tipc/discover.h
@@ -39,12 +39,11 @@
 
 struct link_req;
 
-struct link_req *tipc_disc_init_link_req(struct tipc_bearer *b_ptr,
-					 const struct tipc_media_addr *dest,
-					 u32 dest_domain);
-void tipc_disc_update_link_req(struct link_req *req);
-void tipc_disc_stop_link_req(struct link_req *req);
-
+int tipc_disc_create(struct tipc_bearer *b_ptr, struct tipc_media_addr *dest,
+		     u32 dest_domain);
+void tipc_disc_delete(struct link_req *req);
+void tipc_disc_add_dest(struct link_req *req);
+void tipc_disc_remove_dest(struct link_req *req);
 void tipc_disc_recv_msg(struct sk_buff *buf, struct tipc_bearer *b_ptr);
 
 #endif
diff --git a/net/tipc/link.c b/net/tipc/link.c
index ebf338f7b14..5ed4b4f7452 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -92,7 +92,8 @@ static int  link_recv_changeover_msg(struct link **l_ptr, struct sk_buff **buf);
 static void link_set_supervision_props(struct link *l_ptr, u32 tolerance);
 static int  link_send_sections_long(struct tipc_port *sender,
 				    struct iovec const *msg_sect,
-				    u32 num_sect, u32 destnode);
+				    u32 num_sect, unsigned int total_len,
+				    u32 destnode);
 static void link_check_defragm_bufs(struct link *l_ptr);
 static void link_state_event(struct link *l_ptr, u32 event);
 static void link_reset_statistics(struct link *l_ptr);
@@ -842,6 +843,25 @@ static void link_add_to_outqueue(struct link *l_ptr,
 		l_ptr->stats.max_queue_sz = l_ptr->out_queue_size;
 }
 
+static void link_add_chain_to_outqueue(struct link *l_ptr,
+				       struct sk_buff *buf_chain,
+				       u32 long_msgno)
+{
+	struct sk_buff *buf;
+	struct tipc_msg *msg;
+
+	if (!l_ptr->next_out)
+		l_ptr->next_out = buf_chain;
+	while (buf_chain) {
+		buf = buf_chain;
+		buf_chain = buf_chain->next;
+
+		msg = buf_msg(buf);
+		msg_set_long_msgno(msg, long_msgno);
+		link_add_to_outqueue(l_ptr, buf, msg);
+	}
+}
+
 /*
  * tipc_link_send_buf() is the 'full path' for messages, called from
  * inside TIPC when the 'fast path' in tipc_send_buf
@@ -864,8 +884,9 @@ int tipc_link_send_buf(struct link *l_ptr, struct sk_buff *buf)
 
 	if (unlikely(queue_size >= queue_limit)) {
 		if (imp <= TIPC_CRITICAL_IMPORTANCE) {
-			return link_schedule_port(l_ptr, msg_origport(msg),
-						  size);
+			link_schedule_port(l_ptr, msg_origport(msg), size);
+			buf_discard(buf);
+			return -ELINKCONG;
 		}
 		buf_discard(buf);
 		if (imp > CONN_MANAGER) {
@@ -1042,6 +1063,7 @@ int tipc_send_buf_fast(struct sk_buff *buf, u32 destnode)
 int tipc_link_send_sections_fast(struct tipc_port *sender,
 				 struct iovec const *msg_sect,
 				 const u32 num_sect,
+				 unsigned int total_len,
 				 u32 destaddr)
 {
 	struct tipc_msg *hdr = &sender->phdr;
@@ -1057,8 +1079,8 @@ again:
 	 * (Must not hold any locks while building message.)
 	 */
 
-	res = tipc_msg_build(hdr, msg_sect, num_sect, sender->max_pkt,
-			!sender->user_port, &buf);
+	res = tipc_msg_build(hdr, msg_sect, num_sect, total_len,
+			     sender->max_pkt, !sender->user_port, &buf);
 
 	read_lock_bh(&tipc_net_lock);
 	node = tipc_node_find(destaddr);
@@ -1069,8 +1091,6 @@ again:
 			if (likely(buf)) {
 				res = link_send_buf_fast(l_ptr, buf,
 							 &sender->max_pkt);
-				if (unlikely(res < 0))
-					buf_discard(buf);
 exit:
 				tipc_node_unlock(node);
 				read_unlock_bh(&tipc_net_lock);
@@ -1105,7 +1125,8 @@ exit:
 				goto again;
 
 			return link_send_sections_long(sender, msg_sect,
-						       num_sect, destaddr);
+						       num_sect, total_len,
+						       destaddr);
 		}
 		tipc_node_unlock(node);
 	}
@@ -1117,7 +1138,7 @@ exit:
 		return tipc_reject_msg(buf, TIPC_ERR_NO_NODE);
 	if (res >= 0)
 		return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
-						 TIPC_ERR_NO_NODE);
+						 total_len, TIPC_ERR_NO_NODE);
 	return res;
 }
 
@@ -1138,12 +1159,13 @@ exit:
 static int link_send_sections_long(struct tipc_port *sender,
 				   struct iovec const *msg_sect,
 				   u32 num_sect,
+				   unsigned int total_len,
 				   u32 destaddr)
 {
 	struct link *l_ptr;
 	struct tipc_node *node;
 	struct tipc_msg *hdr = &sender->phdr;
-	u32 dsz = msg_data_sz(hdr);
+	u32 dsz = total_len;
 	u32 max_pkt, fragm_sz, rest;
 	struct tipc_msg fragm_hdr;
 	struct sk_buff *buf, *buf_chain, *prev;
@@ -1169,7 +1191,6 @@ again:
 
 	tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
 		 INT_H_SIZE, msg_destnode(hdr));
-	msg_set_link_selector(&fragm_hdr, sender->ref);
 	msg_set_size(&fragm_hdr, max_pkt);
 	msg_set_fragm_no(&fragm_hdr, 1);
 
@@ -1271,28 +1292,15 @@ reject:
 			buf_discard(buf_chain);
 		}
 		return tipc_port_reject_sections(sender, hdr, msg_sect, num_sect,
-						 TIPC_ERR_NO_NODE);
+						 total_len, TIPC_ERR_NO_NODE);
 	}
 
-	/* Append whole chain to send queue: */
+	/* Append chain of fragments to send queue & send them */
 
-	buf = buf_chain;
-	l_ptr->long_msg_seq_no = mod(l_ptr->long_msg_seq_no + 1);
-	if (!l_ptr->next_out)
-		l_ptr->next_out = buf_chain;
+	l_ptr->long_msg_seq_no++;
+	link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
+	l_ptr->stats.sent_fragments += fragm_no;
 	l_ptr->stats.sent_fragmented++;
-	while (buf) {
-		struct sk_buff *next = buf->next;
-		struct tipc_msg *msg = buf_msg(buf);
-
-		l_ptr->stats.sent_fragments++;
-		msg_set_long_msgno(msg, l_ptr->long_msg_seq_no);
-		link_add_to_outqueue(l_ptr, buf, msg);
-		buf = next;
-	}
-
-	/* Send it, if possible: */
-
 	tipc_link_push_queue(l_ptr);
 	tipc_node_unlock(node);
 	return dsz;
@@ -2407,6 +2415,8 @@ void tipc_link_recv_bundle(struct sk_buff *buf)
  */
 static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf)
 {
+	struct sk_buff *buf_chain = NULL;
+	struct sk_buff *buf_chain_tail = (struct sk_buff *)&buf_chain;
 	struct tipc_msg *inmsg = buf_msg(buf);
 	struct tipc_msg fragm_hdr;
 	u32 insize = msg_size(inmsg);
@@ -2415,7 +2425,7 @@ static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf)
 	u32 rest = insize;
 	u32 pack_sz = l_ptr->max_pkt;
 	u32 fragm_sz = pack_sz - INT_H_SIZE;
-	u32 fragm_no = 1;
+	u32 fragm_no = 0;
 	u32 destaddr;
 
 	if (msg_short(inmsg))
@@ -2427,10 +2437,6 @@ static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf)
 
 	tipc_msg_init(&fragm_hdr, MSG_FRAGMENTER, FIRST_FRAGMENT,
 		 INT_H_SIZE, destaddr);
-	msg_set_link_selector(&fragm_hdr, msg_link_selector(inmsg));
-	msg_set_long_msgno(&fragm_hdr, mod(l_ptr->long_msg_seq_no++));
-	msg_set_fragm_no(&fragm_hdr, fragm_no);
-	l_ptr->stats.sent_fragmented++;
 
 	/* Chop up message: */
 
@@ -2443,27 +2449,37 @@ static int link_send_long_buf(struct link *l_ptr, struct sk_buff *buf)
 		}
 		fragm = tipc_buf_acquire(fragm_sz + INT_H_SIZE);
 		if (fragm == NULL) {
-			warn("Link unable to fragment message\n");
-			dsz = -ENOMEM;
-			goto exit;
+			buf_discard(buf);
+			while (buf_chain) {
+				buf = buf_chain;
+				buf_chain = buf_chain->next;
+				buf_discard(buf);
+			}
+			return -ENOMEM;
 		}
 		msg_set_size(&fragm_hdr, fragm_sz + INT_H_SIZE);
+		fragm_no++;
+		msg_set_fragm_no(&fragm_hdr, fragm_no);
 		skb_copy_to_linear_data(fragm, &fragm_hdr, INT_H_SIZE);
 		skb_copy_to_linear_data_offset(fragm, INT_H_SIZE, crs,
 					       fragm_sz);
-		/*  Send queued messages first, if any: */
+		buf_chain_tail->next = fragm;
+		buf_chain_tail = fragm;
 
-		l_ptr->stats.sent_fragments++;
-		tipc_link_send_buf(l_ptr, fragm);
-		if (!tipc_link_is_up(l_ptr))
-			return dsz;
-		msg_set_fragm_no(&fragm_hdr, ++fragm_no);
 		rest -= fragm_sz;
 		crs += fragm_sz;
 		msg_set_type(&fragm_hdr, FRAGMENT);
 	}
-exit:
 	buf_discard(buf);
+
+	/* Append chain of fragments to send queue & send them */
+
+	l_ptr->long_msg_seq_no++;
+	link_add_chain_to_outqueue(l_ptr, buf_chain, l_ptr->long_msg_seq_no);
+	l_ptr->stats.sent_fragments += fragm_no;
+	l_ptr->stats.sent_fragmented++;
+	tipc_link_push_queue(l_ptr);
+
 	return dsz;
 }
 
diff --git a/net/tipc/link.h b/net/tipc/link.h
index e6a30dbe1aa..74fbecab1ea 100644
--- a/net/tipc/link.h
+++ b/net/tipc/link.h
@@ -228,6 +228,7 @@ u32 tipc_link_get_max_pkt(u32 dest, u32 selector);
 int tipc_link_send_sections_fast(struct tipc_port *sender,
 				 struct iovec const *msg_sect,
 				 const u32 num_sect,
+				 unsigned int total_len,
 				 u32 destnode);
 void tipc_link_recv_bundle(struct sk_buff *buf);
 int  tipc_link_recv_fragment(struct sk_buff **pending,
diff --git a/net/tipc/msg.c b/net/tipc/msg.c
index 6d92d17e7fb..03e57bf92c7 100644
--- a/net/tipc/msg.c
+++ b/net/tipc/msg.c
@@ -68,20 +68,6 @@ void tipc_msg_init(struct tipc_msg *m, u32 user, u32 type,
 }
 
 /**
- * tipc_msg_calc_data_size - determine total data size for message
- */
-
-int tipc_msg_calc_data_size(struct iovec const *msg_sect, u32 num_sect)
-{
-	int dsz = 0;
-	int i;
-
-	for (i = 0; i < num_sect; i++)
-		dsz += msg_sect[i].iov_len;
-	return dsz;
-}
-
-/**
  * tipc_msg_build - create message using specified header and data
  *
  * Note: Caller must not hold any locks in case copy_from_user() is interrupted!
@@ -89,18 +75,13 @@ int tipc_msg_calc_data_size(struct iovec const *msg_sect, u32 num_sect)
  * Returns message data size or errno
  */
 
-int tipc_msg_build(struct tipc_msg *hdr,
-			    struct iovec const *msg_sect, u32 num_sect,
+int tipc_msg_build(struct tipc_msg *hdr, struct iovec const *msg_sect,
+		   u32 num_sect, unsigned int total_len,
 			    int max_size, int usrmem, struct sk_buff **buf)
 {
 	int dsz, sz, hsz, pos, res, cnt;
 
-	dsz = tipc_msg_calc_data_size(msg_sect, num_sect);
-	if (unlikely(dsz > TIPC_MAX_USER_MSG_SIZE)) {
-		*buf = NULL;
-		return -EINVAL;
-	}
-
+	dsz = total_len;
 	pos = hsz = msg_hdr_sz(hdr);
 	sz = hsz + dsz;
 	msg_set_size(hdr, sz);
diff --git a/net/tipc/msg.h b/net/tipc/msg.h
index de02339fc17..8452454731f 100644
--- a/net/tipc/msg.h
+++ b/net/tipc/msg.h
@@ -39,41 +39,24 @@
 
 #include "bearer.h"
 
+/*
+ * Constants and routines used to read and write TIPC payload message headers
+ *
+ * Note: Some items are also used with TIPC internal message headers
+ */
+
 #define TIPC_VERSION              2
 
 /*
- *		TIPC user data message header format, version 2:
- *
- *
- *     1 0 9 8 7 6 5 4|3 2 1 0 9 8 7 6|5 4 3 2 1 0 9 8|7 6 5 4 3 2 1 0
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w0:|vers | user  |hdr sz |n|d|s|-|          message size           |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w1:|mstyp| error |rer cnt|lsc|opt p|      broadcast ack no         |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w2:|        link level ack no      |   broadcast/link level seq no |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w3:|                       previous node                           |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w4:|                      originating port                         |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w5:|                      destination port                         |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w6:|                      originating node                         |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w7:|                      destination node                         |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w8:|            name type / transport sequence number              |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * w9:|              name instance/multicast lower bound              |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * wA:|                    multicast upper bound                      |
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- *    /                                                               /
- *    \                           options                             \
- *    /                                                               /
- *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- *
+ * Payload message users are defined in TIPC's public API:
+ * - TIPC_LOW_IMPORTANCE
+ * - TIPC_MEDIUM_IMPORTANCE
+ * - TIPC_HIGH_IMPORTANCE
+ * - TIPC_CRITICAL_IMPORTANCE
+ */
+
+/*
+ * Payload message types
  */
 
 #define TIPC_CONN_MSG		0
@@ -81,6 +64,9 @@
 #define TIPC_NAMED_MSG		2
 #define TIPC_DIRECT_MSG		3
 
+/*
+ * Message header sizes
+ */
 
 #define SHORT_H_SIZE              24	/* Connected, in-cluster messages */
 #define DIR_MSG_H_SIZE            32	/* Directly addressed messages */
@@ -473,40 +459,11 @@ static inline struct tipc_msg *msg_get_wrapped(struct tipc_msg *m)
 
 
 /*
-		TIPC internal message header format, version 2
-
-       1 0 9 8 7 6 5 4|3 2 1 0 9 8 7 6|5 4 3 2 1 0 9 8|7 6 5 4 3 2 1 0
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w0:|vers |msg usr|hdr sz |n|resrv|            packet size          |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w1:|m typ|      sequence gap       |       broadcast ack no        |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w2:| link level ack no/bc_gap_from |     seq no / bcast_gap_to     |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w3:|                       previous node                           |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w4:|  next sent broadcast/fragm no | next sent pkt/ fragm msg no   |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w5:|          session no           |rsv=0|r|berid|link prio|netpl|p|
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w6:|                      originating node                         |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w7:|                      destination node                         |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w8:|                   transport sequence number                   |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-   w9:|   msg count / bcast tag       |       link tolerance          |
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-      \                                                               \
-      /                     User Specific Data                        /
-      \                                                               \
-      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
-      NB: CONN_MANAGER use data message format. LINK_CONFIG has own format.
-*/
+ * Constants and routines used to read and write TIPC internal message headers
+ */
 
 /*
- * Internal users
+ * Internal message users
  */
 
 #define  BCAST_PROTOCOL       5
@@ -520,7 +477,7 @@ static inline struct tipc_msg *msg_get_wrapped(struct tipc_msg *m)
 #define  LINK_CONFIG          13
 
 /*
- *  Connection management protocol messages
+ *  Connection management protocol message types
  */
 
 #define CONN_PROBE        0
@@ -528,12 +485,41 @@ static inline struct tipc_msg *msg_get_wrapped(struct tipc_msg *m)
 #define CONN_ACK          2
 
 /*
- * Name distributor messages
+ * Name distributor message types
  */
 
 #define PUBLICATION       0
 #define WITHDRAWAL        1
 
+/*
+ * Segmentation message types
+ */
+
+#define FIRST_FRAGMENT		0
+#define FRAGMENT		1
+#define LAST_FRAGMENT		2
+
+/*
+ * Link management protocol message types
+ */
+
+#define STATE_MSG		0
+#define RESET_MSG		1
+#define ACTIVATE_MSG		2
+
+/*
+ * Changeover tunnel message types
+ */
+#define DUPLICATE_MSG		0
+#define ORIGINAL_MSG		1
+
+/*
+ * Config protocol message types
+ */
+
+#define DSC_REQ_MSG		0
+#define DSC_RESP_MSG		1
+
 
 /*
  * Word 1
@@ -761,50 +747,11 @@ static inline void msg_set_link_tolerance(struct tipc_msg *m, u32 n)
 	msg_set_bits(m, 9, 0, 0xffff, n);
 }
 
-/*
- * Segmentation message types
- */
-
-#define FIRST_FRAGMENT     0
-#define FRAGMENT           1
-#define LAST_FRAGMENT      2
-
-/*
- * Link management protocol message types
- */
-
-#define STATE_MSG       0
-#define RESET_MSG       1
-#define ACTIVATE_MSG    2
-
-/*
- * Changeover