1 /* 2 * net/tipc/name_distr.c: TIPC name distribution code 3 * 4 * Copyright (c) 2000-2006, Ericsson AB 5 * Copyright (c) 2005, 2010-2011, 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 "link.h" 39 #include "name_distr.h" 40 41 #define ITEM_SIZE sizeof(struct distr_item) 42 43 /** 44 * struct distr_item - publication info distributed to other nodes 45 * @type: name sequence type 46 * @lower: name sequence lower bound 47 * @upper: name sequence upper bound 48 * @ref: publishing port reference 49 * @key: publication key 50 * 51 * ===> All fields are stored in network byte order. <=== 52 * 53 * First 3 fields identify (name or) name sequence being published. 54 * Reference field uniquely identifies port that published name sequence. 55 * Key field uniquely identifies publication, in the event a port has 56 * multiple publications of the same name sequence. 57 * 58 * Note: There is no field that identifies the publishing node because it is 59 * the same for all items contained within a publication message. 60 */ 61 62 struct distr_item { 63 __be32 type; 64 __be32 lower; 65 __be32 upper; 66 __be32 ref; 67 __be32 key; 68 }; 69 70 /** 71 * List of externally visible publications by this node -- 72 * that is, all publications having scope > TIPC_NODE_SCOPE. 73 */ 74 75 static LIST_HEAD(publ_root); 76 static u32 publ_cnt; 77 78 /** 79 * publ_to_item - add publication info to a publication message 80 */ 81 82 static void publ_to_item(struct distr_item *i, struct publication *p) 83 { 84 i->type = htonl(p->type); 85 i->lower = htonl(p->lower); 86 i->upper = htonl(p->upper); 87 i->ref = htonl(p->ref); 88 i->key = htonl(p->key); 89 } 90 91 /** 92 * named_prepare_buf - allocate & initialize a publication message 93 */ 94 95 static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest) 96 { 97 struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size); 98 struct tipc_msg *msg; 99 100 if (buf != NULL) { 101 msg = buf_msg(buf); 102 tipc_msg_init(msg, NAME_DISTRIBUTOR, type, INT_H_SIZE, dest); 103 msg_set_size(msg, INT_H_SIZE + size); 104 } 105 return buf; 106 } 107 108 static void named_cluster_distribute(struct sk_buff *buf) 109 { 110 struct sk_buff *buf_copy; 111 struct tipc_node *n_ptr; 112 113 list_for_each_entry(n_ptr, &tipc_node_list, list) { 114 if (tipc_node_active_links(n_ptr)) { 115 buf_copy = skb_copy(buf, GFP_ATOMIC); 116 if (!buf_copy) 117 break; 118 msg_set_destnode(buf_msg(buf_copy), n_ptr->addr); 119 tipc_link_send(buf_copy, n_ptr->addr, n_ptr->addr); 120 } 121 } 122 123 buf_discard(buf); 124 } 125 126 /** 127 * tipc_named_publish - tell other nodes about a new publication by this node 128 */ 129 130 void tipc_named_publish(struct publication *publ) 131 { 132 struct sk_buff *buf; 133 struct distr_item *item; 134 135 list_add_tail(&publ->local_list, &publ_root); 136 publ_cnt++; 137 138 buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0); 139 if (!buf) { 140 warn("Publication distribution failure\n"); 141 return; 142 } 143 144 item = (struct distr_item *)msg_data(buf_msg(buf)); 145 publ_to_item(item, publ); 146 named_cluster_distribute(buf); 147 } 148 149 /** 150 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node 151 */ 152 153 void tipc_named_withdraw(struct publication *publ) 154 { 155 struct sk_buff *buf; 156 struct distr_item *item; 157 158 list_del(&publ->local_list); 159 publ_cnt--; 160 161 buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0); 162 if (!buf) { 163 warn("Withdrawal distribution failure\n"); 164 return; 165 } 166 167 item = (struct distr_item *)msg_data(buf_msg(buf)); 168 publ_to_item(item, publ); 169 named_cluster_distribute(buf); 170 } 171 172 /** 173 * tipc_named_node_up - tell specified node about all publications by this node 174 */ 175 176 void tipc_named_node_up(unsigned long nodearg) 177 { 178 struct tipc_node *n_ptr; 179 struct link *l_ptr; 180 struct publication *publ; 181 struct distr_item *item = NULL; 182 struct sk_buff *buf = NULL; 183 struct list_head message_list; 184 u32 node = (u32)nodearg; 185 u32 left = 0; 186 u32 rest; 187 u32 max_item_buf = 0; 188 189 /* compute maximum amount of publication data to send per message */ 190 191 read_lock_bh(&tipc_net_lock); 192 n_ptr = tipc_node_find(node); 193 if (n_ptr) { 194 tipc_node_lock(n_ptr); 195 l_ptr = n_ptr->active_links[0]; 196 if (l_ptr) 197 max_item_buf = ((l_ptr->max_pkt - INT_H_SIZE) / 198 ITEM_SIZE) * ITEM_SIZE; 199 tipc_node_unlock(n_ptr); 200 } 201 read_unlock_bh(&tipc_net_lock); 202 if (!max_item_buf) 203 return; 204 205 /* create list of publication messages, then send them as a unit */ 206 207 INIT_LIST_HEAD(&message_list); 208 209 read_lock_bh(&tipc_nametbl_lock); 210 rest = publ_cnt * ITEM_SIZE; 211 212 list_for_each_entry(publ, &publ_root, local_list) { 213 if (!buf) { 214 left = (rest <= max_item_buf) ? rest : max_item_buf; 215 rest -= left; 216 buf = named_prepare_buf(PUBLICATION, left, node); 217 if (!buf) { 218 warn("Bulk publication distribution failure\n"); 219 goto exit; 220 } 221 item = (struct distr_item *)msg_data(buf_msg(buf)); 222 } 223 publ_to_item(item, publ); 224 item++; 225 left -= ITEM_SIZE; 226 if (!left) { 227 list_add_tail((struct list_head *)buf, &message_list); 228 buf = NULL; 229 } 230 } 231 exit: 232 read_unlock_bh(&tipc_nametbl_lock); 233 234 tipc_link_send_names(&message_list, (u32)node); 235 } 236 237 /** 238 * named_purge_publ - remove publication associated with a failed node 239 * 240 * Invoked for each publication issued by a newly failed node. 241 * Removes publication structure from name table & deletes it. 242 * In rare cases the link may have come back up again when this 243 * function is called, and we have two items representing the same 244 * publication. Nudge this item's key to distinguish it from the other. 245 */ 246 247 static void named_purge_publ(struct publication *publ) 248 { 249 struct publication *p; 250 251 write_lock_bh(&tipc_nametbl_lock); 252 publ->key += 1222345; 253 p = tipc_nametbl_remove_publ(publ->type, publ->lower, 254 publ->node, publ->ref, publ->key); 255 if (p) 256 tipc_nodesub_unsubscribe(&p->subscr); 257 write_unlock_bh(&tipc_nametbl_lock); 258 259 if (p != publ) { 260 err("Unable to remove publication from failed node\n" 261 "(type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n", 262 publ->type, publ->lower, publ->node, publ->ref, publ->key); 263 } 264 265 kfree(p); 266 } 267 268 /** 269 * tipc_named_recv - process name table update message sent by another node 270 */ 271 272 void tipc_named_recv(struct sk_buff *buf) 273 { 274 struct publication *publ; 275 struct tipc_msg *msg = buf_msg(buf); 276 struct distr_item *item = (struct distr_item *)msg_data(msg); 277 u32 count = msg_data_sz(msg) / ITEM_SIZE; 278 279 write_lock_bh(&tipc_nametbl_lock); 280 while (count--) { 281 if (msg_type(msg) == PUBLICATION) { 282 publ = tipc_nametbl_insert_publ(ntohl(item->type), 283 ntohl(item->lower), 284 ntohl(item->upper), 285 TIPC_CLUSTER_SCOPE, 286 msg_orignode(msg), 287 ntohl(item->ref), 288 ntohl(item->key)); 289 if (publ) { 290 tipc_nodesub_subscribe(&publ->subscr, 291 msg_orignode(msg), 292 publ, 293 (net_ev_handler) 294 named_purge_publ); 295 } 296 } else if (msg_type(msg) == WITHDRAWAL) { 297 publ = tipc_nametbl_remove_publ(ntohl(item->type), 298 ntohl(item->lower), 299 msg_orignode(msg), 300 ntohl(item->ref), 301 ntohl(item->key)); 302 303 if (publ) { 304 tipc_nodesub_unsubscribe(&publ->subscr); 305 kfree(publ); 306 } else { 307 err("Unable to remove publication by node 0x%x\n" 308 "(type=%u, lower=%u, ref=%u, key=%u)\n", 309 msg_orignode(msg), 310 ntohl(item->type), ntohl(item->lower), 311 ntohl(item->ref), ntohl(item->key)); 312 } 313 } else { 314 warn("Unrecognized name table message received\n"); 315 } 316 item++; 317 } 318 write_unlock_bh(&tipc_nametbl_lock); 319 buf_discard(buf); 320 } 321 322 /** 323 * tipc_named_reinit - re-initialize local publication list 324 * 325 * This routine is called whenever TIPC networking is (re)enabled. 326 * All existing publications by this node that have "cluster" or "zone" scope 327 * are updated to reflect the node's current network address. 328 * (If the node's address is unchanged, the update loop terminates immediately.) 329 */ 330 331 void tipc_named_reinit(void) 332 { 333 struct publication *publ; 334 335 write_lock_bh(&tipc_nametbl_lock); 336 list_for_each_entry(publ, &publ_root, local_list) { 337 if (publ->node == tipc_own_addr) 338 break; 339 publ->node = tipc_own_addr; 340 } 341 write_unlock_bh(&tipc_nametbl_lock); 342 } 343