diff options
Diffstat (limited to 'net/tipc/name_distr.c')
-rw-r--r-- | net/tipc/name_distr.c | 306 |
1 files changed, 306 insertions, 0 deletions
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); +} |