[TIPC] Initial merge

TIPC (Transparent Inter Process Communication) is a protocol designed for
intra cluster communication. For more information see
http://tipc.sourceforge.net

Signed-off-by: Per Liden <per.liden@nospam.ericsson.com>
diff --git a/net/tipc/name_distr.c b/net/tipc/name_distr.c
new file mode 100644
index 0000000..5e0604c
--- /dev/null
+++ b/net/tipc/name_distr.c
@@ -0,0 +1,306 @@
+/*
+ * net/tipc/name_distr.c: TIPC name distribution code
+ * 
+ * Copyright (c) 2003-2005, Ericsson Research Canada
+ * Copyright (c) 2005, Wind River Systems
+ * Copyright (c) 2005-2006, Ericsson AB
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without 
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this 
+ * list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright notice, 
+ * this list of conditions and the following disclaimer in the documentation 
+ * and/or other materials provided with the distribution.
+ * Neither the names of the copyright holders nor the names of its 
+ * contributors may be used to endorse or promote products derived from this 
+ * software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core.h"
+#include "cluster.h"
+#include "dbg.h"
+#include "link.h"
+#include "msg.h"
+#include "name_distr.h"
+
+#undef  DBG_OUTPUT
+#define DBG_OUTPUT NULL
+
+#define ITEM_SIZE sizeof(struct distr_item)
+
+/**
+ * struct distr_item - publication info distributed to other nodes
+ * @type: name sequence type
+ * @lower: name sequence lower bound
+ * @upper: name sequence upper bound
+ * @ref: publishing port reference
+ * @key: publication key
+ * 
+ * ===> All fields are stored in network byte order. <===
+ * 
+ * First 3 fields identify (name or) name sequence being published.
+ * Reference field uniquely identifies port that published name sequence.
+ * Key field uniquely identifies publication, in the event a port has
+ * multiple publications of the same name sequence.
+ * 
+ * Note: There is no field that identifies the publishing node because it is 
+ * the same for all items contained within a publication message.
+ */
+
+struct distr_item {
+	u32 type;
+	u32 lower;
+	u32 upper;
+	u32 ref;
+	u32 key;
+};
+
+/**
+ * List of externally visible publications by this node -- 
+ * that is, all publications having scope > TIPC_NODE_SCOPE.
+ */
+
+static LIST_HEAD(publ_root);
+static u32 publ_cnt = 0;		
+
+/**
+ * publ_to_item - add publication info to a publication message
+ */
+
+static void publ_to_item(struct distr_item *i, struct publication *p)
+{
+	i->type = htonl(p->type);
+	i->lower = htonl(p->lower);
+	i->upper = htonl(p->upper);
+	i->ref = htonl(p->ref);
+	i->key = htonl(p->key);
+	dbg("publ_to_item: %u, %u, %u\n", p->type, p->lower, p->upper);
+}
+
+/**
+ * named_prepare_buf - allocate & initialize a publication message
+ */
+
+static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
+{
+	struct sk_buff *buf = buf_acquire(LONG_H_SIZE + size);  
+	struct tipc_msg *msg;
+
+	if (buf != NULL) {
+		msg = buf_msg(buf);
+		msg_init(msg, NAME_DISTRIBUTOR, type, TIPC_OK, 
+			 LONG_H_SIZE, dest);
+		msg_set_size(msg, LONG_H_SIZE + size);
+	}
+	return buf;
+}
+
+/**
+ * named_publish - tell other nodes about a new publication by this node
+ */
+
+void named_publish(struct publication *publ)
+{
+	struct sk_buff *buf;
+	struct distr_item *item;
+
+	list_add(&publ->local_list, &publ_root);
+	publ_cnt++;
+
+	buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
+	if (!buf) {
+		warn("Memory squeeze; failed to distribute publication\n");
+		return;
+	}
+
+	item = (struct distr_item *)msg_data(buf_msg(buf));
+	publ_to_item(item, publ);
+	dbg("named_withdraw: broadcasting publish msg\n");
+	cluster_broadcast(buf);
+}
+
+/**
+ * named_withdraw - tell other nodes about a withdrawn publication by this node
+ */
+
+void named_withdraw(struct publication *publ)
+{
+	struct sk_buff *buf;
+	struct distr_item *item;
+
+	list_del(&publ->local_list);
+	publ_cnt--;
+
+	buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
+	if (!buf) {
+		warn("Memory squeeze; failed to distribute withdrawal\n");
+		return;
+	}
+
+	item = (struct distr_item *)msg_data(buf_msg(buf));
+	publ_to_item(item, publ);
+	dbg("named_withdraw: broadcasting withdraw msg\n");
+	cluster_broadcast(buf);
+}
+
+/**
+ * named_node_up - tell specified node about all publications by this node
+ */
+
+void named_node_up(unsigned long node)
+{
+	struct publication *publ;
+	struct distr_item *item = 0;
+	struct sk_buff *buf = 0;
+	u32 left = 0;
+	u32 rest;
+	u32 max_item_buf;
+
+	assert(in_own_cluster(node));
+	read_lock_bh(&nametbl_lock); 
+	max_item_buf = TIPC_MAX_USER_MSG_SIZE / ITEM_SIZE;
+	max_item_buf *= ITEM_SIZE;
+	rest = publ_cnt * ITEM_SIZE;
+
+	list_for_each_entry(publ, &publ_root, local_list) {
+		if (!buf) {
+			left = (rest <= max_item_buf) ? rest : max_item_buf;
+			rest -= left;
+			buf = named_prepare_buf(PUBLICATION, left, node);       
+			if (buf == NULL) {
+				warn("Memory Squeeze; could not send publication\n");
+				goto exit;
+			}
+			item = (struct distr_item *)msg_data(buf_msg(buf));
+		}
+		publ_to_item(item, publ);
+		item++;
+		left -= ITEM_SIZE;
+		if (!left) {
+			msg_set_link_selector(buf_msg(buf), node);
+			dbg("named_node_up: sending publish msg to "
+			    "<%u.%u.%u>\n", tipc_zone(node), 
+			    tipc_cluster(node), tipc_node(node));
+			link_send(buf, node, node);
+			buf = 0;
+		}
+	}
+exit:
+	read_unlock_bh(&nametbl_lock); 
+}
+
+/**
+ * node_is_down - remove publication associated with a failed node
+ * 
+ * Invoked for each publication issued by a newly failed node.  
+ * Removes publication structure from name table & deletes it.
+ * In rare cases the link may have come back up again when this
+ * function is called, and we have two items representing the same
+ * publication. Nudge this item's key to distinguish it from the other.
+ * (Note: Publication's node subscription is already unsubscribed.)
+ */
+
+static void node_is_down(struct publication *publ)
+{
+	struct publication *p;
+        write_lock_bh(&nametbl_lock);
+	dbg("node_is_down: withdrawing %u, %u, %u\n", 
+	    publ->type, publ->lower, publ->upper);
+        publ->key += 1222345;
+	p = nametbl_remove_publ(publ->type, publ->lower, 
+				publ->node, publ->ref, publ->key);
+        assert(p == publ);
+	write_unlock_bh(&nametbl_lock);
+	if (publ)
+		kfree(publ);
+}
+
+/**
+ * named_recv - process name table update message sent by another node
+ */
+
+void named_recv(struct sk_buff *buf)
+{
+	struct publication *publ;
+	struct tipc_msg *msg = buf_msg(buf);
+	struct distr_item *item = (struct distr_item *)msg_data(msg);
+	u32 count = msg_data_sz(msg) / ITEM_SIZE;
+
+	write_lock_bh(&nametbl_lock); 
+	while (count--) {
+		if (msg_type(msg) == PUBLICATION) {
+			dbg("named_recv: got publication for %u, %u, %u\n", 
+			    ntohl(item->type), ntohl(item->lower),
+			    ntohl(item->upper));
+			publ = nametbl_insert_publ(ntohl(item->type), 
+						   ntohl(item->lower),
+						   ntohl(item->upper),
+						   TIPC_CLUSTER_SCOPE,
+						   msg_orignode(msg), 
+						   ntohl(item->ref),
+						   ntohl(item->key));
+			if (publ) {
+				nodesub_subscribe(&publ->subscr, 
+						  msg_orignode(msg), 
+						  publ,
+						  (net_ev_handler)node_is_down);
+			}
+		} else if (msg_type(msg) == WITHDRAWAL) {
+			dbg("named_recv: got withdrawl for %u, %u, %u\n", 
+			    ntohl(item->type), ntohl(item->lower),
+			    ntohl(item->upper));
+			publ = nametbl_remove_publ(ntohl(item->type),
+						   ntohl(item->lower),
+						   msg_orignode(msg),
+						   ntohl(item->ref),
+						   ntohl(item->key));
+
+			if (publ) {
+				nodesub_unsubscribe(&publ->subscr);
+        			kfree(publ);
+			}
+		} else {
+			warn("named_recv: unknown msg\n");
+		}
+		item++;
+	}
+	write_unlock_bh(&nametbl_lock); 
+	buf_discard(buf);
+}
+
+/**
+ * named_reinit - re-initialize local publication list
+ * 
+ * This routine is called whenever TIPC networking is (re)enabled.
+ * All existing publications by this node that have "cluster" or "zone" scope
+ * are updated to reflect the node's current network address.
+ * (If the node's address is unchanged, the update loop terminates immediately.)
+ */
+
+void named_reinit(void)
+{
+	struct publication *publ;
+
+	write_lock_bh(&nametbl_lock); 
+	list_for_each_entry(publ, &publ_root, local_list) {
+		if (publ->node == tipc_own_addr)
+			break;
+		publ->node = tipc_own_addr;
+	}
+	write_unlock_bh(&nametbl_lock); 
+}