Subversion Repositories or1k_soc_on_altera_embedded_dev_kit

/*

 * 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 {

        __be32 type;

        __be32 lower;

        __be32 upper;

        __be32 ref;

        __be32 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_tail(&publ->local_list, &publ_root);

        publ_cnt++;

        buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);

        if (!buf) {

                warn("Publication distribution failure\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("Withdrawl distribution failure\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;

        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) {

                                warn("Bulk publication distribution failure\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);

        write_unlock_bh(&tipc_nametbl_lock);

        if (p != publ) {

                err("Unable to remove publication from failed node\n"

                    "(type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",

                    publ->type, publ->lower, publ->node, publ->ref, publ->key);

        }

        if (p) {

                kfree(p);

        }

}

/**

 * 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 {

                                err("Unable to remove publication by node 0x%x\n"

                                    "(type=%u, lower=%u, ref=%u, key=%u)\n",

                                    msg_orignode(msg),

                                    ntohl(item->type), ntohl(item->lower),

                                    ntohl(item->ref), ntohl(item->key));

                        }

                } else {

                        warn("Unrecognized name table message received\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);

}