--- /dev/null
+/*
+ * net/tipc/name_distr.c: TIPC name distribution code
+ *
+ * Copyright (c) 2000-2006, Ericsson AB
+ * Copyright (c) 2005, Wind River Systems
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "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;
+}
+
+/**
+ * tipc_named_publish - tell other nodes about a new publication by this node
+ */
+
+void tipc_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("tipc_named_withdraw: broadcasting publish msg\n");
+ tipc_cltr_broadcast(buf);
+}
+
+/**
+ * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
+ */
+
+void tipc_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("tipc_named_withdraw: broadcasting withdraw msg\n");
+ tipc_cltr_broadcast(buf);
+}
+
+/**
+ * tipc_named_node_up - tell specified node about all publications by this node
+ */
+
+void tipc_named_node_up(unsigned long node)
+{
+ struct publication *publ;
+ struct distr_item *item = NULL;
+ struct sk_buff *buf = NULL;
+ u32 left = 0;
+ u32 rest;
+ u32 max_item_buf;
+
+ assert(in_own_cluster(node));
+ read_lock_bh(&tipc_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("tipc_named_node_up: sending publish msg to "
+ "<%u.%u.%u>\n", tipc_zone(node),
+ tipc_cluster(node), tipc_node(node));
+ tipc_link_send(buf, node, node);
+ buf = NULL;
+ }
+ }
+exit:
+ read_unlock_bh(&tipc_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(&tipc_nametbl_lock);
+ dbg("node_is_down: withdrawing %u, %u, %u\n",
+ publ->type, publ->lower, publ->upper);
+ publ->key += 1222345;
+ p = tipc_nametbl_remove_publ(publ->type, publ->lower,
+ publ->node, publ->ref, publ->key);
+ assert(p == publ);
+ write_unlock_bh(&tipc_nametbl_lock);
+ kfree(publ);
+}
+
+/**
+ * tipc_named_recv - process name table update message sent by another node
+ */
+
+void tipc_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(&tipc_nametbl_lock);
+ while (count--) {
+ if (msg_type(msg) == PUBLICATION) {
+ dbg("tipc_named_recv: got publication for %u, %u, %u\n",
+ ntohl(item->type), ntohl(item->lower),
+ ntohl(item->upper));
+ publ = tipc_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) {
+ tipc_nodesub_subscribe(&publ->subscr,
+ msg_orignode(msg),
+ publ,
+ (net_ev_handler)node_is_down);
+ }
+ } else if (msg_type(msg) == WITHDRAWAL) {
+ dbg("tipc_named_recv: got withdrawl for %u, %u, %u\n",
+ ntohl(item->type), ntohl(item->lower),
+ ntohl(item->upper));
+ publ = tipc_nametbl_remove_publ(ntohl(item->type),
+ ntohl(item->lower),
+ msg_orignode(msg),
+ ntohl(item->ref),
+ ntohl(item->key));
+
+ if (publ) {
+ tipc_nodesub_unsubscribe(&publ->subscr);
+ kfree(publ);
+ }
+ } else {
+ warn("tipc_named_recv: unknown msg\n");
+ }
+ item++;
+ }
+ write_unlock_bh(&tipc_nametbl_lock);
+ buf_discard(buf);
+}
+
+/**
+ * tipc_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 tipc_named_reinit(void)
+{
+ struct publication *publ;
+
+ write_lock_bh(&tipc_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(&tipc_nametbl_lock);
+}
git://git.onelab.eu / linux-2.6.git / blobdiff