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 #define ITEM_SIZE sizeof(struct distr_item) 45 46 /** 47 * struct distr_item - publication info distributed to other nodes 48 * @type: name sequence type 49 * @lower: name sequence lower bound 50 * @upper: name sequence upper bound 51 * @ref: publishing port reference 52 * @key: publication key 53 * 54 * ===> All fields are stored in network byte order. <=== 55 * 56 * First 3 fields identify (name or) name sequence being published. 57 * Reference field uniquely identifies port that published name sequence. 58 * Key field uniquely identifies publication, in the event a port has 59 * multiple publications of the same name sequence. 60 * 61 * Note: There is no field that identifies the publishing node because it is 62 * the same for all items contained within a publication message. 63 */ 64 65 struct distr_item { 66 __be32 type; 67 __be32 lower; 68 __be32 upper; 69 __be32 ref; 70 __be32 key; 71 }; 72 73 /** 74 * List of externally visible publications by this node -- 75 * that is, all publications having scope > TIPC_NODE_SCOPE. 76 */ 77 78 static LIST_HEAD(publ_root); 79 static u32 publ_cnt = 0; 80 81 /** 82 * publ_to_item - add publication info to a publication message 83 */ 84 85 static void publ_to_item(struct distr_item *i, struct publication *p) 86 { 87 i->type = htonl(p->type); 88 i->lower = htonl(p->lower); 89 i->upper = htonl(p->upper); 90 i->ref = htonl(p->ref); 91 i->key = htonl(p->key); 92 dbg("publ_to_item: %u, %u, %u\n", p->type, p->lower, p->upper); 93 } 94 95 /** 96 * named_prepare_buf - allocate & initialize a publication message 97 */ 98 99 static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest) 100 { 101 struct sk_buff *buf = buf_acquire(LONG_H_SIZE + size); 102 struct tipc_msg *msg; 103 104 if (buf != NULL) { 105 msg = buf_msg(buf); 106 msg_init(msg, NAME_DISTRIBUTOR, type, LONG_H_SIZE, dest); 107 msg_set_size(msg, LONG_H_SIZE + size); 108 } 109 return buf; 110 } 111 112 /** 113 * tipc_named_publish - tell other nodes about a new publication by this node 114 */ 115 116 void tipc_named_publish(struct publication *publ) 117 { 118 struct sk_buff *buf; 119 struct distr_item *item; 120 121 list_add_tail(&publ->local_list, &publ_root); 122 publ_cnt++; 123 124 buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0); 125 if (!buf) { 126 warn("Publication distribution failure\n"); 127 return; 128 } 129 130 item = (struct distr_item *)msg_data(buf_msg(buf)); 131 publ_to_item(item, publ); 132 dbg("tipc_named_withdraw: broadcasting publish msg\n"); 133 tipc_cltr_broadcast(buf); 134 } 135 136 /** 137 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node 138 */ 139 140 void tipc_named_withdraw(struct publication *publ) 141 { 142 struct sk_buff *buf; 143 struct distr_item *item; 144 145 list_del(&publ->local_list); 146 publ_cnt--; 147 148 buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0); 149 if (!buf) { 150 warn("Withdrawl distribution failure\n"); 151 return; 152 } 153 154 item = (struct distr_item *)msg_data(buf_msg(buf)); 155 publ_to_item(item, publ); 156 dbg("tipc_named_withdraw: broadcasting withdraw msg\n"); 157 tipc_cltr_broadcast(buf); 158 } 159 160 /** 161 * tipc_named_node_up - tell specified node about all publications by this node 162 */ 163 164 void tipc_named_node_up(unsigned long node) 165 { 166 struct publication *publ; 167 struct distr_item *item = NULL; 168 struct sk_buff *buf = NULL; 169 u32 left = 0; 170 u32 rest; 171 u32 max_item_buf; 172 173 read_lock_bh(&tipc_nametbl_lock); 174 max_item_buf = TIPC_MAX_USER_MSG_SIZE / ITEM_SIZE; 175 max_item_buf *= ITEM_SIZE; 176 rest = publ_cnt * ITEM_SIZE; 177 178 list_for_each_entry(publ, &publ_root, local_list) { 179 if (!buf) { 180 left = (rest <= max_item_buf) ? rest : max_item_buf; 181 rest -= left; 182 buf = named_prepare_buf(PUBLICATION, left, node); 183 if (!buf) { 184 warn("Bulk publication distribution failure\n"); 185 goto exit; 186 } 187 item = (struct distr_item *)msg_data(buf_msg(buf)); 188 } 189 publ_to_item(item, publ); 190 item++; 191 left -= ITEM_SIZE; 192 if (!left) { 193 msg_set_link_selector(buf_msg(buf), node); 194 dbg("tipc_named_node_up: sending publish msg to " 195 "<%u.%u.%u>\n", tipc_zone(node), 196 tipc_cluster(node), tipc_node(node)); 197 tipc_link_send(buf, node, node); 198 buf = NULL; 199 } 200 } 201 exit: 202 read_unlock_bh(&tipc_nametbl_lock); 203 } 204 205 /** 206 * node_is_down - remove publication associated with a failed node 207 * 208 * Invoked for each publication issued by a newly failed node. 209 * Removes publication structure from name table & deletes it. 210 * In rare cases the link may have come back up again when this 211 * function is called, and we have two items representing the same 212 * publication. Nudge this item's key to distinguish it from the other. 213 * (Note: Publication's node subscription is already unsubscribed.) 214 */ 215 216 static void node_is_down(struct publication *publ) 217 { 218 struct publication *p; 219 220 write_lock_bh(&tipc_nametbl_lock); 221 dbg("node_is_down: withdrawing %u, %u, %u\n", 222 publ->type, publ->lower, publ->upper); 223 publ->key += 1222345; 224 p = tipc_nametbl_remove_publ(publ->type, publ->lower, 225 publ->node, publ->ref, publ->key); 226 write_unlock_bh(&tipc_nametbl_lock); 227 228 if (p != publ) { 229 err("Unable to remove publication from failed node\n" 230 "(type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n", 231 publ->type, publ->lower, publ->node, publ->ref, publ->key); 232 } 233 234 if (p) { 235 kfree(p); 236 } 237 } 238 239 /** 240 * tipc_named_recv - process name table update message sent by another node 241 */ 242 243 void tipc_named_recv(struct sk_buff *buf) 244 { 245 struct publication *publ; 246 struct tipc_msg *msg = buf_msg(buf); 247 struct distr_item *item = (struct distr_item *)msg_data(msg); 248 u32 count = msg_data_sz(msg) / ITEM_SIZE; 249 250 write_lock_bh(&tipc_nametbl_lock); 251 while (count--) { 252 if (msg_type(msg) == PUBLICATION) { 253 dbg("tipc_named_recv: got publication for %u, %u, %u\n", 254 ntohl(item->type), ntohl(item->lower), 255 ntohl(item->upper)); 256 publ = tipc_nametbl_insert_publ(ntohl(item->type), 257 ntohl(item->lower), 258 ntohl(item->upper), 259 TIPC_CLUSTER_SCOPE, 260 msg_orignode(msg), 261 ntohl(item->ref), 262 ntohl(item->key)); 263 if (publ) { 264 tipc_nodesub_subscribe(&publ->subscr, 265 msg_orignode(msg), 266 publ, 267 (net_ev_handler)node_is_down); 268 } 269 } else if (msg_type(msg) == WITHDRAWAL) { 270 dbg("tipc_named_recv: got withdrawl for %u, %u, %u\n", 271 ntohl(item->type), ntohl(item->lower), 272 ntohl(item->upper)); 273 publ = tipc_nametbl_remove_publ(ntohl(item->type), 274 ntohl(item->lower), 275 msg_orignode(msg), 276 ntohl(item->ref), 277 ntohl(item->key)); 278 279 if (publ) { 280 tipc_nodesub_unsubscribe(&publ->subscr); 281 kfree(publ); 282 } else { 283 err("Unable to remove publication by node 0x%x\n" 284 "(type=%u, lower=%u, ref=%u, key=%u)\n", 285 msg_orignode(msg), 286 ntohl(item->type), ntohl(item->lower), 287 ntohl(item->ref), ntohl(item->key)); 288 } 289 } else { 290 warn("Unrecognized name table message received\n"); 291 } 292 item++; 293 } 294 write_unlock_bh(&tipc_nametbl_lock); 295 buf_discard(buf); 296 } 297 298 /** 299 * tipc_named_reinit - re-initialize local publication list 300 * 301 * This routine is called whenever TIPC networking is (re)enabled. 302 * All existing publications by this node that have "cluster" or "zone" scope 303 * are updated to reflect the node's current network address. 304 * (If the node's address is unchanged, the update loop terminates immediately.) 305 */ 306 307 void tipc_named_reinit(void) 308 { 309 struct publication *publ; 310 311 write_lock_bh(&tipc_nametbl_lock); 312 list_for_each_entry(publ, &publ_root, local_list) { 313 if (publ->node == tipc_own_addr) 314 break; 315 publ->node = tipc_own_addr; 316 } 317 write_unlock_bh(&tipc_nametbl_lock); 318 } 319