1 /* 2 * net/tipc/node.c: TIPC node management routines 3 * 4 * Copyright (c) 2000-2006, Ericsson AB 5 * Copyright (c) 2005-2006, 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 "config.h" 39 #include "node.h" 40 #include "name_distr.h" 41 42 static void node_lost_contact(struct tipc_node *n_ptr); 43 static void node_established_contact(struct tipc_node *n_ptr); 44 45 static DEFINE_SPINLOCK(node_create_lock); 46 47 u32 tipc_own_tag; 48 49 /** 50 * tipc_node_create - create neighboring node 51 * 52 * Currently, this routine is called by neighbor discovery code, which holds 53 * net_lock for reading only. We must take node_create_lock to ensure a node 54 * isn't created twice if two different bearers discover the node at the same 55 * time. (It would be preferable to switch to holding net_lock in write mode, 56 * but this is a non-trivial change.) 57 */ 58 59 struct tipc_node *tipc_node_create(u32 addr) 60 { 61 struct tipc_node *n_ptr; 62 u32 n_num; 63 64 spin_lock_bh(&node_create_lock); 65 66 n_ptr = tipc_node_find(addr); 67 if (n_ptr) { 68 spin_unlock_bh(&node_create_lock); 69 return n_ptr; 70 } 71 72 n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC); 73 if (!n_ptr) { 74 spin_unlock_bh(&node_create_lock); 75 warn("Node creation failed, no memory\n"); 76 return NULL; 77 } 78 79 n_ptr->addr = addr; 80 spin_lock_init(&n_ptr->lock); 81 INIT_LIST_HEAD(&n_ptr->nsub); 82 83 n_num = tipc_node(addr); 84 tipc_net.nodes[n_num] = n_ptr; 85 if (n_num > tipc_net.highest_node) 86 tipc_net.highest_node = n_num; 87 88 spin_unlock_bh(&node_create_lock); 89 return n_ptr; 90 } 91 92 void tipc_node_delete(struct tipc_node *n_ptr) 93 { 94 u32 n_num; 95 96 if (!n_ptr) 97 return; 98 99 n_num = tipc_node(n_ptr->addr); 100 tipc_net.nodes[n_num] = NULL; 101 kfree(n_ptr); 102 103 while (!tipc_net.nodes[tipc_net.highest_node]) 104 if (--tipc_net.highest_node == 0) 105 break; 106 } 107 108 109 /** 110 * tipc_node_link_up - handle addition of link 111 * 112 * Link becomes active (alone or shared) or standby, depending on its priority. 113 */ 114 115 void tipc_node_link_up(struct tipc_node *n_ptr, struct link *l_ptr) 116 { 117 struct link **active = &n_ptr->active_links[0]; 118 119 n_ptr->working_links++; 120 121 info("Established link <%s> on network plane %c\n", 122 l_ptr->name, l_ptr->b_ptr->net_plane); 123 124 if (!active[0]) { 125 active[0] = active[1] = l_ptr; 126 node_established_contact(n_ptr); 127 return; 128 } 129 if (l_ptr->priority < active[0]->priority) { 130 info("New link <%s> becomes standby\n", l_ptr->name); 131 return; 132 } 133 tipc_link_send_duplicate(active[0], l_ptr); 134 if (l_ptr->priority == active[0]->priority) { 135 active[0] = l_ptr; 136 return; 137 } 138 info("Old link <%s> becomes standby\n", active[0]->name); 139 if (active[1] != active[0]) 140 info("Old link <%s> becomes standby\n", active[1]->name); 141 active[0] = active[1] = l_ptr; 142 } 143 144 /** 145 * node_select_active_links - select active link 146 */ 147 148 static void node_select_active_links(struct tipc_node *n_ptr) 149 { 150 struct link **active = &n_ptr->active_links[0]; 151 u32 i; 152 u32 highest_prio = 0; 153 154 active[0] = active[1] = NULL; 155 156 for (i = 0; i < MAX_BEARERS; i++) { 157 struct link *l_ptr = n_ptr->links[i]; 158 159 if (!l_ptr || !tipc_link_is_up(l_ptr) || 160 (l_ptr->priority < highest_prio)) 161 continue; 162 163 if (l_ptr->priority > highest_prio) { 164 highest_prio = l_ptr->priority; 165 active[0] = active[1] = l_ptr; 166 } else { 167 active[1] = l_ptr; 168 } 169 } 170 } 171 172 /** 173 * tipc_node_link_down - handle loss of link 174 */ 175 176 void tipc_node_link_down(struct tipc_node *n_ptr, struct link *l_ptr) 177 { 178 struct link **active; 179 180 n_ptr->working_links--; 181 182 if (!tipc_link_is_active(l_ptr)) { 183 info("Lost standby link <%s> on network plane %c\n", 184 l_ptr->name, l_ptr->b_ptr->net_plane); 185 return; 186 } 187 info("Lost link <%s> on network plane %c\n", 188 l_ptr->name, l_ptr->b_ptr->net_plane); 189 190 active = &n_ptr->active_links[0]; 191 if (active[0] == l_ptr) 192 active[0] = active[1]; 193 if (active[1] == l_ptr) 194 active[1] = active[0]; 195 if (active[0] == l_ptr) 196 node_select_active_links(n_ptr); 197 if (tipc_node_is_up(n_ptr)) 198 tipc_link_changeover(l_ptr); 199 else 200 node_lost_contact(n_ptr); 201 } 202 203 int tipc_node_has_active_links(struct tipc_node *n_ptr) 204 { 205 return n_ptr->active_links[0] != NULL; 206 } 207 208 int tipc_node_has_redundant_links(struct tipc_node *n_ptr) 209 { 210 return n_ptr->working_links > 1; 211 } 212 213 int tipc_node_is_up(struct tipc_node *n_ptr) 214 { 215 return tipc_node_has_active_links(n_ptr); 216 } 217 218 struct tipc_node *tipc_node_attach_link(struct link *l_ptr) 219 { 220 struct tipc_node *n_ptr = tipc_node_find(l_ptr->addr); 221 222 if (!n_ptr) 223 n_ptr = tipc_node_create(l_ptr->addr); 224 if (n_ptr) { 225 u32 bearer_id = l_ptr->b_ptr->identity; 226 char addr_string[16]; 227 228 if (n_ptr->link_cnt >= 2) { 229 err("Attempt to create third link to %s\n", 230 tipc_addr_string_fill(addr_string, n_ptr->addr)); 231 return NULL; 232 } 233 234 if (!n_ptr->links[bearer_id]) { 235 n_ptr->links[bearer_id] = l_ptr; 236 tipc_net.links++; 237 n_ptr->link_cnt++; 238 return n_ptr; 239 } 240 err("Attempt to establish second link on <%s> to %s\n", 241 l_ptr->b_ptr->name, 242 tipc_addr_string_fill(addr_string, l_ptr->addr)); 243 } 244 return NULL; 245 } 246 247 void tipc_node_detach_link(struct tipc_node *n_ptr, struct link *l_ptr) 248 { 249 n_ptr->links[l_ptr->b_ptr->identity] = NULL; 250 tipc_net.links--; 251 n_ptr->link_cnt--; 252 } 253 254 /* 255 * Routing table management - five cases to handle: 256 * 257 * 1: A link towards a zone/cluster external node comes up. 258 * => Send a multicast message updating routing tables of all 259 * system nodes within own cluster that the new destination 260 * can be reached via this node. 261 * (node.establishedContact()=>cluster.multicastNewRoute()) 262 * 263 * 2: A link towards a slave node comes up. 264 * => Send a multicast message updating routing tables of all 265 * system nodes within own cluster that the new destination 266 * can be reached via this node. 267 * (node.establishedContact()=>cluster.multicastNewRoute()) 268 * => Send a message to the slave node about existence 269 * of all system nodes within cluster: 270 * (node.establishedContact()=>cluster.sendLocalRoutes()) 271 * 272 * 3: A new cluster local system node becomes available. 273 * => Send message(s) to this particular node containing 274 * information about all cluster external and slave 275 * nodes which can be reached via this node. 276 * (node.establishedContact()==>network.sendExternalRoutes()) 277 * (node.establishedContact()==>network.sendSlaveRoutes()) 278 * => Send messages to all directly connected slave nodes 279 * containing information about the existence of the new node 280 * (node.establishedContact()=>cluster.multicastNewRoute()) 281 * 282 * 4: The link towards a zone/cluster external node or slave 283 * node goes down. 284 * => Send a multcast message updating routing tables of all 285 * nodes within cluster that the new destination can not any 286 * longer be reached via this node. 287 * (node.lostAllLinks()=>cluster.bcastLostRoute()) 288 * 289 * 5: A cluster local system node becomes unavailable. 290 * => Remove all references to this node from the local 291 * routing tables. Note: This is a completely node 292 * local operation. 293 * (node.lostAllLinks()=>network.removeAsRouter()) 294 * => Send messages to all directly connected slave nodes 295 * containing information about loss of the node 296 * (node.establishedContact()=>cluster.multicastLostRoute()) 297 * 298 */ 299 300 static void node_established_contact(struct tipc_node *n_ptr) 301 { 302 tipc_k_signal((Handler)tipc_named_node_up, n_ptr->addr); 303 304 /* Syncronize broadcast acks */ 305 n_ptr->bclink.acked = tipc_bclink_get_last_sent(); 306 307 if (n_ptr->bclink.supported) { 308 tipc_nmap_add(&tipc_bcast_nmap, n_ptr->addr); 309 if (n_ptr->addr < tipc_own_addr) 310 tipc_own_tag++; 311 } 312 } 313 314 static void node_cleanup_finished(unsigned long node_addr) 315 { 316 struct tipc_node *n_ptr; 317 318 read_lock_bh(&tipc_net_lock); 319 n_ptr = tipc_node_find(node_addr); 320 if (n_ptr) { 321 tipc_node_lock(n_ptr); 322 n_ptr->cleanup_required = 0; 323 tipc_node_unlock(n_ptr); 324 } 325 read_unlock_bh(&tipc_net_lock); 326 } 327 328 static void node_lost_contact(struct tipc_node *n_ptr) 329 { 330 char addr_string[16]; 331 u32 i; 332 333 /* Clean up broadcast reception remains */ 334 n_ptr->bclink.gap_after = n_ptr->bclink.gap_to = 0; 335 while (n_ptr->bclink.deferred_head) { 336 struct sk_buff *buf = n_ptr->bclink.deferred_head; 337 n_ptr->bclink.deferred_head = buf->next; 338 buf_discard(buf); 339 } 340 if (n_ptr->bclink.defragm) { 341 buf_discard(n_ptr->bclink.defragm); 342 n_ptr->bclink.defragm = NULL; 343 } 344 345 if (n_ptr->bclink.supported) { 346 tipc_bclink_acknowledge(n_ptr, 347 mod(n_ptr->bclink.acked + 10000)); 348 tipc_nmap_remove(&tipc_bcast_nmap, n_ptr->addr); 349 if (n_ptr->addr < tipc_own_addr) 350 tipc_own_tag--; 351 } 352 353 info("Lost contact with %s\n", 354 tipc_addr_string_fill(addr_string, n_ptr->addr)); 355 356 /* Abort link changeover */ 357 for (i = 0; i < MAX_BEARERS; i++) { 358 struct link *l_ptr = n_ptr->links[i]; 359 if (!l_ptr) 360 continue; 361 l_ptr->reset_checkpoint = l_ptr->next_in_no; 362 l_ptr->exp_msg_count = 0; 363 tipc_link_reset_fragments(l_ptr); 364 } 365 366 /* Notify subscribers */ 367 tipc_nodesub_notify(n_ptr); 368 369 /* Prevent re-contact with node until all cleanup is done */ 370 371 n_ptr->cleanup_required = 1; 372 tipc_k_signal((Handler)node_cleanup_finished, n_ptr->addr); 373 } 374 375 struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space) 376 { 377 u32 domain; 378 struct sk_buff *buf; 379 struct tipc_node *n_ptr; 380 struct tipc_node_info node_info; 381 u32 payload_size; 382 u32 n_num; 383 384 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR)) 385 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 386 387 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area)); 388 if (!tipc_addr_domain_valid(domain)) 389 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE 390 " (network address)"); 391 392 read_lock_bh(&tipc_net_lock); 393 if (!tipc_net.nodes) { 394 read_unlock_bh(&tipc_net_lock); 395 return tipc_cfg_reply_none(); 396 } 397 398 /* For now, get space for all other nodes */ 399 400 payload_size = TLV_SPACE(sizeof(node_info)) * 401 (tipc_net.highest_node - 1); 402 if (payload_size > 32768u) { 403 read_unlock_bh(&tipc_net_lock); 404 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED 405 " (too many nodes)"); 406 } 407 buf = tipc_cfg_reply_alloc(payload_size); 408 if (!buf) { 409 read_unlock_bh(&tipc_net_lock); 410 return NULL; 411 } 412 413 /* Add TLVs for all nodes in scope */ 414 415 for (n_num = 1; n_num <= tipc_net.highest_node; n_num++) { 416 n_ptr = tipc_net.nodes[n_num]; 417 if (!n_ptr || !tipc_in_scope(domain, n_ptr->addr)) 418 continue; 419 node_info.addr = htonl(n_ptr->addr); 420 node_info.up = htonl(tipc_node_is_up(n_ptr)); 421 tipc_cfg_append_tlv(buf, TIPC_TLV_NODE_INFO, 422 &node_info, sizeof(node_info)); 423 } 424 425 read_unlock_bh(&tipc_net_lock); 426 return buf; 427 } 428 429 struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space) 430 { 431 u32 domain; 432 struct sk_buff *buf; 433 struct tipc_node *n_ptr; 434 struct tipc_link_info link_info; 435 u32 payload_size; 436 u32 n_num; 437 438 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR)) 439 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR); 440 441 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area)); 442 if (!tipc_addr_domain_valid(domain)) 443 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE 444 " (network address)"); 445 446 if (tipc_mode != TIPC_NET_MODE) 447 return tipc_cfg_reply_none(); 448 449 read_lock_bh(&tipc_net_lock); 450 451 /* Get space for all unicast links + multicast link */ 452 453 payload_size = TLV_SPACE(sizeof(link_info)) * (tipc_net.links + 1); 454 if (payload_size > 32768u) { 455 read_unlock_bh(&tipc_net_lock); 456 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED 457 " (too many links)"); 458 } 459 buf = tipc_cfg_reply_alloc(payload_size); 460 if (!buf) { 461 read_unlock_bh(&tipc_net_lock); 462 return NULL; 463 } 464 465 /* Add TLV for broadcast link */ 466 467 link_info.dest = htonl(tipc_cluster_mask(tipc_own_addr)); 468 link_info.up = htonl(1); 469 strlcpy(link_info.str, tipc_bclink_name, TIPC_MAX_LINK_NAME); 470 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info)); 471 472 /* Add TLVs for any other links in scope */ 473 474 for (n_num = 1; n_num <= tipc_net.highest_node; n_num++) { 475 u32 i; 476 477 n_ptr = tipc_net.nodes[n_num]; 478 if (!n_ptr || !tipc_in_scope(domain, n_ptr->addr)) 479 continue; 480 tipc_node_lock(n_ptr); 481 for (i = 0; i < MAX_BEARERS; i++) { 482 if (!n_ptr->links[i]) 483 continue; 484 link_info.dest = htonl(n_ptr->addr); 485 link_info.up = htonl(tipc_link_is_up(n_ptr->links[i])); 486 strcpy(link_info.str, n_ptr->links[i]->name); 487 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, 488 &link_info, sizeof(link_info)); 489 } 490 tipc_node_unlock(n_ptr); 491 } 492 493 read_unlock_bh(&tipc_net_lock); 494 return buf; 495 } 496