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 "addr.h" 39 #include "link.h" 40 #include "name_distr.h" 41 42 #define ITEM_SIZE sizeof(struct distr_item) 43 44 /** 45 * struct distr_item - publication info distributed to other nodes 46 * @type: name sequence type 47 * @lower: name sequence lower bound 48 * @upper: name sequence upper bound 49 * @ref: publishing port reference 50 * @key: publication key 51 * 52 * ===> All fields are stored in network byte order. <=== 53 * 54 * First 3 fields identify (name or) name sequence being published. 55 * Reference field uniquely identifies port that published name sequence. 56 * Key field uniquely identifies publication, in the event a port has 57 * multiple publications of the same name sequence. 58 * 59 * Note: There is no field that identifies the publishing node because it is 60 * the same for all items contained within a publication message. 61 */ 62 63 struct distr_item { 64 __be32 type; 65 __be32 lower; 66 __be32 upper; 67 __be32 ref; 68 __be32 key; 69 }; 70 71 /** 72 * List of externally visible publications by this node -- 73 * that is, all publications having scope > TIPC_NODE_SCOPE. 74 */ 75 76 static LIST_HEAD(publ_root); 77 static u32 publ_cnt = 0; 78 79 /** 80 * publ_to_item - add publication info to a publication message 81 */ 82 83 static void publ_to_item(struct distr_item *i, struct publication *p) 84 { 85 i->type = htonl(p->type); 86 i->lower = htonl(p->lower); 87 i->upper = htonl(p->upper); 88 i->ref = htonl(p->ref); 89 i->key = htonl(p->key); 90 dbg("publ_to_item: %u, %u, %u\n", p->type, p->lower, p->upper); 91 } 92 93 /** 94 * named_prepare_buf - allocate & initialize a publication message 95 */ 96 97 static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest) 98 { 99 struct sk_buff *buf = tipc_buf_acquire(LONG_H_SIZE + size); 100 struct tipc_msg *msg; 101 102 if (buf != NULL) { 103 msg = buf_msg(buf); 104 tipc_msg_init(msg, NAME_DISTRIBUTOR, type, LONG_H_SIZE, dest); 105 msg_set_size(msg, LONG_H_SIZE + size); 106 } 107 return buf; 108 } 109 110 static void named_cluster_distribute(struct sk_buff *buf) 111 { 112 struct sk_buff *buf_copy; 113 struct tipc_node *n_ptr; 114 u32 n_num; 115 116 for (n_num = 1; n_num <= tipc_net.highest_node; n_num++) { 117 n_ptr = tipc_net.nodes[n_num]; 118 if (n_ptr && tipc_node_has_active_links(n_ptr)) { 119 buf_copy = skb_copy(buf, GFP_ATOMIC); 120 if (!buf_copy) 121 break; 122 msg_set_destnode(buf_msg(buf_copy), n_ptr->addr); 123 tipc_link_send(buf_copy, n_ptr->addr, n_ptr->addr); 124 } 125 } 126 127 buf_discard(buf); 128 } 129 130 /** 131 * tipc_named_publish - tell other nodes about a new publication by this node 132 */ 133 134 void tipc_named_publish(struct publication *publ) 135 { 136 struct sk_buff *buf; 137 struct distr_item *item; 138 139 list_add_tail(&publ->local_list, &publ_root); 140 publ_cnt++; 141 142 buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0); 143 if (!buf) { 144 warn("Publication distribution failure\n"); 145 return; 146 } 147 148 item = (struct distr_item *)msg_data(buf_msg(buf)); 149 publ_to_item(item, publ); 150 dbg("tipc_named_publish: broadcasting publish msg\n"); 151 named_cluster_distribute(buf); 152 } 153 154 /** 155 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node 156 */ 157 158 void tipc_named_withdraw(struct publication *publ) 159 { 160 struct sk_buff *buf; 161 struct distr_item *item; 162 163 list_del(&publ->local_list); 164 publ_cnt--; 165 166 buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0); 167 if (!buf) { 168 warn("Withdrawl distribution failure\n"); 169 return; 170 } 171 172 item = (struct distr_item *)msg_data(buf_msg(buf)); 173 publ_to_item(item, publ); 174 dbg("tipc_named_withdraw: broadcasting withdraw msg\n"); 175 named_cluster_distribute(buf); 176 } 177 178 /** 179 * tipc_named_node_up - tell specified node about all publications by this node 180 */ 181 182 void tipc_named_node_up(unsigned long node) 183 { 184 struct publication *publ; 185 struct distr_item *item = NULL; 186 struct sk_buff *buf = NULL; 187 u32 left = 0; 188 u32 rest; 189 u32 max_item_buf; 190 191 read_lock_bh(&tipc_nametbl_lock); 192 max_item_buf = TIPC_MAX_USER_MSG_SIZE / ITEM_SIZE; 193 max_item_buf *= ITEM_SIZE; 194 rest = publ_cnt * ITEM_SIZE; 195 196 list_for_each_entry(publ, &publ_root, local_list) { 197 if (!buf) { 198 left = (rest <= max_item_buf) ? rest : max_item_buf; 199 rest -= left; 200 buf = named_prepare_buf(PUBLICATION, left, node); 201 if (!buf) { 202 warn("Bulk publication distribution failure\n"); 203 goto exit; 204 } 205 item = (struct distr_item *)msg_data(buf_msg(buf)); 206 } 207 publ_to_item(item, publ); 208 item++; 209 left -= ITEM_SIZE; 210 if (!left) { 211 msg_set_link_selector(buf_msg(buf), node); 212 dbg("tipc_named_node_up: sending publish msg to " 213 "<%u.%u.%u>\n", tipc_zone(node), 214 tipc_cluster(node), tipc_node(node)); 215 tipc_link_send(buf, node, node); 216 buf = NULL; 217 } 218 } 219 exit: 220 read_unlock_bh(&tipc_nametbl_lock); 221 } 222 223 /** 224 * node_is_down - remove publication associated with a failed node 225 * 226 * Invoked for each publication issued by a newly failed node. 227 * Removes publication structure from name table & deletes it. 228 * In rare cases the link may have come back up again when this 229 * function is called, and we have two items representing the same 230 * publication. Nudge this item's key to distinguish it from the other. 231 * (Note: Publication's node subscription is already unsubscribed.) 232 */ 233 234 static void node_is_down(struct publication *publ) 235 { 236 struct publication *p; 237 238 write_lock_bh(&tipc_nametbl_lock); 239 dbg("node_is_down: withdrawing %u, %u, %u\n", 240 publ->type, publ->lower, publ->upper); 241 publ->key += 1222345; 242 p = tipc_nametbl_remove_publ(publ->type, publ->lower, 243 publ->node, publ->ref, publ->key); 244 write_unlock_bh(&tipc_nametbl_lock); 245 246 if (p != publ) { 247 err("Unable to remove publication from failed node\n" 248 "(type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n", 249 publ->type, publ->lower, publ->node, publ->ref, publ->key); 250 } 251 252 if (p) { 253 kfree(p); 254 } 255 } 256 257 /** 258 * tipc_named_recv - process name table update message sent by another node 259 */ 260 261 void tipc_named_recv(struct sk_buff *buf) 262 { 263 struct publication *publ; 264 struct tipc_msg *msg = buf_msg(buf); 265 struct distr_item *item = (struct distr_item *)msg_data(msg); 266 u32 count = msg_data_sz(msg) / ITEM_SIZE; 267 268 write_lock_bh(&tipc_nametbl_lock); 269 while (count--) { 270 if (msg_type(msg) == PUBLICATION) { 271 dbg("tipc_named_recv: got publication for %u, %u, %u\n", 272 ntohl(item->type), ntohl(item->lower), 273 ntohl(item->upper)); 274 publ = tipc_nametbl_insert_publ(ntohl(item->type), 275 ntohl(item->lower), 276 ntohl(item->upper), 277 TIPC_CLUSTER_SCOPE, 278 msg_orignode(msg), 279 ntohl(item->ref), 280 ntohl(item->key)); 281 if (publ) { 282 tipc_nodesub_subscribe(&publ->subscr, 283 msg_orignode(msg), 284 publ, 285 (net_ev_handler)node_is_down); 286 } 287 } else if (msg_type(msg) == WITHDRAWAL) { 288 dbg("tipc_named_recv: got withdrawl for %u, %u, %u\n", 289 ntohl(item->type), ntohl(item->lower), 290 ntohl(item->upper)); 291 publ = tipc_nametbl_remove_publ(ntohl(item->type), 292 ntohl(item->lower), 293 msg_orignode(msg), 294 ntohl(item->ref), 295 ntohl(item->key)); 296 297 if (publ) { 298 tipc_nodesub_unsubscribe(&publ->subscr); 299 kfree(publ); 300 } else { 301 err("Unable to remove publication by node 0x%x\n" 302 "(type=%u, lower=%u, ref=%u, key=%u)\n", 303 msg_orignode(msg), 304 ntohl(item->type), ntohl(item->lower), 305 ntohl(item->ref), ntohl(item->key)); 306 } 307 } else { 308 warn("Unrecognized name table message received\n"); 309 } 310 item++; 311 } 312 write_unlock_bh(&tipc_nametbl_lock); 313 buf_discard(buf); 314 } 315 316 /** 317 * tipc_named_reinit - re-initialize local publication list 318 * 319 * This routine is called whenever TIPC networking is (re)enabled. 320 * All existing publications by this node that have "cluster" or "zone" scope 321 * are updated to reflect the node's current network address. 322 * (If the node's address is unchanged, the update loop terminates immediately.) 323 */ 324 325 void tipc_named_reinit(void) 326 { 327 struct publication *publ; 328 329 write_lock_bh(&tipc_nametbl_lock); 330 list_for_each_entry(publ, &publ_root, local_list) { 331 if (publ->node == tipc_own_addr) 332 break; 333 publ->node = tipc_own_addr; 334 } 335 write_unlock_bh(&tipc_nametbl_lock); 336 } 337