name_distr.c revision a10bd924a421e0e5d5bb9640735b9317b8e473b5
1/* 2 * net/tipc/name_distr.c: TIPC name distribution code 3 * 4 * Copyright (c) 2000-2006, Ericsson AB 5 * Copyright (c) 2005, Wind River Systems 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the names of the copyright holders nor the names of its 17 * contributors may be used to endorse or promote products derived from 18 * this software without specific prior written permission. 19 * 20 * Alternatively, this software may be distributed under the terms of the 21 * GNU General Public License ("GPL") version 2 as published by the Free 22 * Software Foundation. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 34 * POSSIBILITY OF SUCH DAMAGE. 35 */ 36 37#include "core.h" 38#include "cluster.h" 39#include "dbg.h" 40#include "link.h" 41#include "msg.h" 42#include "name_distr.h" 43 44#undef DBG_OUTPUT 45#define DBG_OUTPUT NULL 46 47#define ITEM_SIZE sizeof(struct distr_item) 48 49/** 50 * struct distr_item - publication info distributed to other nodes 51 * @type: name sequence type 52 * @lower: name sequence lower bound 53 * @upper: name sequence upper bound 54 * @ref: publishing port reference 55 * @key: publication key 56 * 57 * ===> All fields are stored in network byte order. <=== 58 * 59 * First 3 fields identify (name or) name sequence being published. 60 * Reference field uniquely identifies port that published name sequence. 61 * Key field uniquely identifies publication, in the event a port has 62 * multiple publications of the same name sequence. 63 * 64 * Note: There is no field that identifies the publishing node because it is 65 * the same for all items contained within a publication message. 66 */ 67 68struct distr_item { 69 u32 type; 70 u32 lower; 71 u32 upper; 72 u32 ref; 73 u32 key; 74}; 75 76/** 77 * List of externally visible publications by this node -- 78 * that is, all publications having scope > TIPC_NODE_SCOPE. 79 */ 80 81static LIST_HEAD(publ_root); 82static u32 publ_cnt = 0; 83 84/** 85 * publ_to_item - add publication info to a publication message 86 */ 87 88static void publ_to_item(struct distr_item *i, struct publication *p) 89{ 90 i->type = htonl(p->type); 91 i->lower = htonl(p->lower); 92 i->upper = htonl(p->upper); 93 i->ref = htonl(p->ref); 94 i->key = htonl(p->key); 95 dbg("publ_to_item: %u, %u, %u\n", p->type, p->lower, p->upper); 96} 97 98/** 99 * named_prepare_buf - allocate & initialize a publication message 100 */ 101 102static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest) 103{ 104 struct sk_buff *buf = buf_acquire(LONG_H_SIZE + size); 105 struct tipc_msg *msg; 106 107 if (buf != NULL) { 108 msg = buf_msg(buf); 109 msg_init(msg, NAME_DISTRIBUTOR, type, TIPC_OK, 110 LONG_H_SIZE, dest); 111 msg_set_size(msg, LONG_H_SIZE + size); 112 } 113 return buf; 114} 115 116/** 117 * tipc_named_publish - tell other nodes about a new publication by this node 118 */ 119 120void tipc_named_publish(struct publication *publ) 121{ 122 struct sk_buff *buf; 123 struct distr_item *item; 124 125 list_add(&publ->local_list, &publ_root); 126 publ_cnt++; 127 128 buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0); 129 if (!buf) { 130 warn("Publication distribution failure\n"); 131 return; 132 } 133 134 item = (struct distr_item *)msg_data(buf_msg(buf)); 135 publ_to_item(item, publ); 136 dbg("tipc_named_withdraw: broadcasting publish msg\n"); 137 tipc_cltr_broadcast(buf); 138} 139 140/** 141 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node 142 */ 143 144void tipc_named_withdraw(struct publication *publ) 145{ 146 struct sk_buff *buf; 147 struct distr_item *item; 148 149 list_del(&publ->local_list); 150 publ_cnt--; 151 152 buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0); 153 if (!buf) { 154 warn("Withdrawl distribution failure\n"); 155 return; 156 } 157 158 item = (struct distr_item *)msg_data(buf_msg(buf)); 159 publ_to_item(item, publ); 160 dbg("tipc_named_withdraw: broadcasting withdraw msg\n"); 161 tipc_cltr_broadcast(buf); 162} 163 164/** 165 * tipc_named_node_up - tell specified node about all publications by this node 166 */ 167 168void tipc_named_node_up(unsigned long node) 169{ 170 struct publication *publ; 171 struct distr_item *item = NULL; 172 struct sk_buff *buf = NULL; 173 u32 left = 0; 174 u32 rest; 175 u32 max_item_buf; 176 177 read_lock_bh(&tipc_nametbl_lock); 178 max_item_buf = TIPC_MAX_USER_MSG_SIZE / ITEM_SIZE; 179 max_item_buf *= ITEM_SIZE; 180 rest = publ_cnt * ITEM_SIZE; 181 182 list_for_each_entry(publ, &publ_root, local_list) { 183 if (!buf) { 184 left = (rest <= max_item_buf) ? rest : max_item_buf; 185 rest -= left; 186 buf = named_prepare_buf(PUBLICATION, left, node); 187 if (!buf) { 188 warn("Bulk publication distribution failure\n"); 189 goto exit; 190 } 191 item = (struct distr_item *)msg_data(buf_msg(buf)); 192 } 193 publ_to_item(item, publ); 194 item++; 195 left -= ITEM_SIZE; 196 if (!left) { 197 msg_set_link_selector(buf_msg(buf), node); 198 dbg("tipc_named_node_up: sending publish msg to " 199 "<%u.%u.%u>\n", tipc_zone(node), 200 tipc_cluster(node), tipc_node(node)); 201 tipc_link_send(buf, node, node); 202 buf = NULL; 203 } 204 } 205exit: 206 read_unlock_bh(&tipc_nametbl_lock); 207} 208 209/** 210 * node_is_down - remove publication associated with a failed node 211 * 212 * Invoked for each publication issued by a newly failed node. 213 * Removes publication structure from name table & deletes it. 214 * In rare cases the link may have come back up again when this 215 * function is called, and we have two items representing the same 216 * publication. Nudge this item's key to distinguish it from the other. 217 * (Note: Publication's node subscription is already unsubscribed.) 218 */ 219 220static void node_is_down(struct publication *publ) 221{ 222 struct publication *p; 223 224 write_lock_bh(&tipc_nametbl_lock); 225 dbg("node_is_down: withdrawing %u, %u, %u\n", 226 publ->type, publ->lower, publ->upper); 227 publ->key += 1222345; 228 p = tipc_nametbl_remove_publ(publ->type, publ->lower, 229 publ->node, publ->ref, publ->key); 230 write_unlock_bh(&tipc_nametbl_lock); 231 232 if (p != publ) { 233 err("Unable to remove publication from failed node\n" 234 "(type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n", 235 publ->type, publ->lower, publ->node, publ->ref, publ->key); 236 } 237 238 if (p) { 239 kfree(p); 240 } 241} 242 243/** 244 * tipc_named_recv - process name table update message sent by another node 245 */ 246 247void tipc_named_recv(struct sk_buff *buf) 248{ 249 struct publication *publ; 250 struct tipc_msg *msg = buf_msg(buf); 251 struct distr_item *item = (struct distr_item *)msg_data(msg); 252 u32 count = msg_data_sz(msg) / ITEM_SIZE; 253 254 write_lock_bh(&tipc_nametbl_lock); 255 while (count--) { 256 if (msg_type(msg) == PUBLICATION) { 257 dbg("tipc_named_recv: got publication for %u, %u, %u\n", 258 ntohl(item->type), ntohl(item->lower), 259 ntohl(item->upper)); 260 publ = tipc_nametbl_insert_publ(ntohl(item->type), 261 ntohl(item->lower), 262 ntohl(item->upper), 263 TIPC_CLUSTER_SCOPE, 264 msg_orignode(msg), 265 ntohl(item->ref), 266 ntohl(item->key)); 267 if (publ) { 268 tipc_nodesub_subscribe(&publ->subscr, 269 msg_orignode(msg), 270 publ, 271 (net_ev_handler)node_is_down); 272 } 273 } else if (msg_type(msg) == WITHDRAWAL) { 274 dbg("tipc_named_recv: got withdrawl for %u, %u, %u\n", 275 ntohl(item->type), ntohl(item->lower), 276 ntohl(item->upper)); 277 publ = tipc_nametbl_remove_publ(ntohl(item->type), 278 ntohl(item->lower), 279 msg_orignode(msg), 280 ntohl(item->ref), 281 ntohl(item->key)); 282 283 if (publ) { 284 tipc_nodesub_unsubscribe(&publ->subscr); 285 kfree(publ); 286 } else { 287 err("Unable to remove publication by node 0x%x\n" 288 "(type=%u, lower=%u, ref=%u, key=%u)\n", 289 msg_orignode(msg), 290 ntohl(item->type), ntohl(item->lower), 291 ntohl(item->ref), ntohl(item->key)); 292 } 293 } else { 294 warn("Unrecognized name table message received\n"); 295 } 296 item++; 297 } 298 write_unlock_bh(&tipc_nametbl_lock); 299 buf_discard(buf); 300} 301 302/** 303 * tipc_named_reinit - re-initialize local publication list 304 * 305 * This routine is called whenever TIPC networking is (re)enabled. 306 * All existing publications by this node that have "cluster" or "zone" scope 307 * are updated to reflect the node's current network address. 308 * (If the node's address is unchanged, the update loop terminates immediately.) 309 */ 310 311void tipc_named_reinit(void) 312{ 313 struct publication *publ; 314 315 write_lock_bh(&tipc_nametbl_lock); 316 list_for_each_entry(publ, &publ_root, local_list) { 317 if (publ->node == tipc_own_addr) 318 break; 319 publ->node = tipc_own_addr; 320 } 321 write_unlock_bh(&tipc_nametbl_lock); 322} 323