1 /* 2 * net/tipc/name_distr.c: TIPC name distribution code 3 * 4 * Copyright (c) 2000-2006, 2014, 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 int sysctl_tipc_named_timeout __read_mostly = 2000; 42 43 /** 44 * struct tipc_dist_queue - queue holding deferred name table updates 45 */ 46 static struct list_head tipc_dist_queue = LIST_HEAD_INIT(tipc_dist_queue); 47 48 struct distr_queue_item { 49 struct distr_item i; 50 u32 dtype; 51 u32 node; 52 unsigned long expires; 53 struct list_head next; 54 }; 55 56 /** 57 * publ_to_item - add publication info to a publication message 58 */ 59 static void publ_to_item(struct distr_item *i, struct publication *p) 60 { 61 i->type = htonl(p->type); 62 i->lower = htonl(p->lower); 63 i->upper = htonl(p->upper); 64 i->ref = htonl(p->ref); 65 i->key = htonl(p->key); 66 } 67 68 /** 69 * named_prepare_buf - allocate & initialize a publication message 70 */ 71 static struct sk_buff *named_prepare_buf(struct net *net, u32 type, u32 size, 72 u32 dest) 73 { 74 struct tipc_net *tn = net_generic(net, tipc_net_id); 75 struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size); 76 struct tipc_msg *msg; 77 78 if (buf != NULL) { 79 msg = buf_msg(buf); 80 tipc_msg_init(tn->own_addr, msg, NAME_DISTRIBUTOR, type, 81 INT_H_SIZE, dest); 82 msg_set_size(msg, INT_H_SIZE + size); 83 } 84 return buf; 85 } 86 87 /** 88 * tipc_named_publish - tell other nodes about a new publication by this node 89 */ 90 struct sk_buff *tipc_named_publish(struct net *net, struct publication *publ) 91 { 92 struct tipc_net *tn = net_generic(net, tipc_net_id); 93 struct sk_buff *buf; 94 struct distr_item *item; 95 96 list_add_tail_rcu(&publ->local_list, 97 &tn->nametbl->publ_list[publ->scope]); 98 99 if (publ->scope == TIPC_NODE_SCOPE) 100 return NULL; 101 102 buf = named_prepare_buf(net, PUBLICATION, ITEM_SIZE, 0); 103 if (!buf) { 104 pr_warn("Publication distribution failure\n"); 105 return NULL; 106 } 107 108 item = (struct distr_item *)msg_data(buf_msg(buf)); 109 publ_to_item(item, publ); 110 return buf; 111 } 112 113 /** 114 * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node 115 */ 116 struct sk_buff *tipc_named_withdraw(struct net *net, struct publication *publ) 117 { 118 struct sk_buff *buf; 119 struct distr_item *item; 120 121 list_del(&publ->local_list); 122 123 if (publ->scope == TIPC_NODE_SCOPE) 124 return NULL; 125 126 buf = named_prepare_buf(net, WITHDRAWAL, ITEM_SIZE, 0); 127 if (!buf) { 128 pr_warn("Withdrawal distribution failure\n"); 129 return NULL; 130 } 131 132 item = (struct distr_item *)msg_data(buf_msg(buf)); 133 publ_to_item(item, publ); 134 return buf; 135 } 136 137 /** 138 * named_distribute - prepare name info for bulk distribution to another node 139 * @list: list of messages (buffers) to be returned from this function 140 * @dnode: node to be updated 141 * @pls: linked list of publication items to be packed into buffer chain 142 */ 143 static void named_distribute(struct net *net, struct sk_buff_head *list, 144 u32 dnode, struct list_head *pls) 145 { 146 struct publication *publ; 147 struct sk_buff *skb = NULL; 148 struct distr_item *item = NULL; 149 uint msg_dsz = (tipc_node_get_mtu(net, dnode, 0) / ITEM_SIZE) * 150 ITEM_SIZE; 151 uint msg_rem = msg_dsz; 152 153 list_for_each_entry(publ, pls, local_list) { 154 /* Prepare next buffer: */ 155 if (!skb) { 156 skb = named_prepare_buf(net, PUBLICATION, msg_rem, 157 dnode); 158 if (!skb) { 159 pr_warn("Bulk publication failure\n"); 160 return; 161 } 162 item = (struct distr_item *)msg_data(buf_msg(skb)); 163 } 164 165 /* Pack publication into message: */ 166 publ_to_item(item, publ); 167 item++; 168 msg_rem -= ITEM_SIZE; 169 170 /* Append full buffer to list: */ 171 if (!msg_rem) { 172 __skb_queue_tail(list, skb); 173 skb = NULL; 174 msg_rem = msg_dsz; 175 } 176 } 177 if (skb) { 178 msg_set_size(buf_msg(skb), INT_H_SIZE + (msg_dsz - msg_rem)); 179 skb_trim(skb, INT_H_SIZE + (msg_dsz - msg_rem)); 180 __skb_queue_tail(list, skb); 181 } 182 } 183 184 /** 185 * tipc_named_node_up - tell specified node about all publications by this node 186 */ 187 void tipc_named_node_up(struct net *net, u32 dnode) 188 { 189 struct tipc_net *tn = net_generic(net, tipc_net_id); 190 struct sk_buff_head head; 191 192 __skb_queue_head_init(&head); 193 194 rcu_read_lock(); 195 named_distribute(net, &head, dnode, 196 &tn->nametbl->publ_list[TIPC_CLUSTER_SCOPE]); 197 named_distribute(net, &head, dnode, 198 &tn->nametbl->publ_list[TIPC_ZONE_SCOPE]); 199 rcu_read_unlock(); 200 201 tipc_node_xmit(net, &head, dnode, 0); 202 } 203 204 /** 205 * tipc_publ_purge - remove publication associated with a failed node 206 * 207 * Invoked for each publication issued by a newly failed node. 208 * Removes publication structure from name table & deletes it. 209 */ 210 static void tipc_publ_purge(struct net *net, struct publication *publ, u32 addr) 211 { 212 struct tipc_net *tn = net_generic(net, tipc_net_id); 213 struct publication *p; 214 215 spin_lock_bh(&tn->nametbl_lock); 216 p = tipc_nametbl_remove_publ(net, publ->type, publ->lower, 217 publ->node, publ->ref, publ->key); 218 if (p) 219 tipc_node_unsubscribe(net, &p->nodesub_list, addr); 220 spin_unlock_bh(&tn->nametbl_lock); 221 222 if (p != publ) { 223 pr_err("Unable to remove publication from failed node\n" 224 " (type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n", 225 publ->type, publ->lower, publ->node, publ->ref, 226 publ->key); 227 } 228 229 kfree_rcu(p, rcu); 230 } 231 232 void tipc_publ_notify(struct net *net, struct list_head *nsub_list, u32 addr) 233 { 234 struct publication *publ, *tmp; 235 236 list_for_each_entry_safe(publ, tmp, nsub_list, nodesub_list) 237 tipc_publ_purge(net, publ, addr); 238 } 239 240 /** 241 * tipc_update_nametbl - try to process a nametable update and notify 242 * subscribers 243 * 244 * tipc_nametbl_lock must be held. 245 * Returns the publication item if successful, otherwise NULL. 246 */ 247 static bool tipc_update_nametbl(struct net *net, struct distr_item *i, 248 u32 node, u32 dtype) 249 { 250 struct publication *publ = NULL; 251 252 if (dtype == PUBLICATION) { 253 publ = tipc_nametbl_insert_publ(net, ntohl(i->type), 254 ntohl(i->lower), 255 ntohl(i->upper), 256 TIPC_CLUSTER_SCOPE, node, 257 ntohl(i->ref), ntohl(i->key)); 258 if (publ) { 259 tipc_node_subscribe(net, &publ->nodesub_list, node); 260 return true; 261 } 262 } else if (dtype == WITHDRAWAL) { 263 publ = tipc_nametbl_remove_publ(net, ntohl(i->type), 264 ntohl(i->lower), 265 node, ntohl(i->ref), 266 ntohl(i->key)); 267 if (publ) { 268 tipc_node_unsubscribe(net, &publ->nodesub_list, node); 269 kfree_rcu(publ, rcu); 270 return true; 271 } 272 } else { 273 pr_warn("Unrecognized name table message received\n"); 274 } 275 return false; 276 } 277 278 /** 279 * tipc_named_add_backlog - add a failed name table update to the backlog 280 * 281 */ 282 static void tipc_named_add_backlog(struct distr_item *i, u32 type, u32 node) 283 { 284 struct distr_queue_item *e; 285 unsigned long now = get_jiffies_64(); 286 287 e = kzalloc(sizeof(*e), GFP_ATOMIC); 288 if (!e) 289 return; 290 e->dtype = type; 291 e->node = node; 292 e->expires = now + msecs_to_jiffies(sysctl_tipc_named_timeout); 293 memcpy(e, i, sizeof(*i)); 294 list_add_tail(&e->next, &tipc_dist_queue); 295 } 296 297 /** 298 * tipc_named_process_backlog - try to process any pending name table updates 299 * from the network. 300 */ 301 void tipc_named_process_backlog(struct net *net) 302 { 303 struct distr_queue_item *e, *tmp; 304 char addr[16]; 305 unsigned long now = get_jiffies_64(); 306 307 list_for_each_entry_safe(e, tmp, &tipc_dist_queue, next) { 308 if (time_after(e->expires, now)) { 309 if (!tipc_update_nametbl(net, &e->i, e->node, e->dtype)) 310 continue; 311 } else { 312 tipc_addr_string_fill(addr, e->node); 313 pr_warn_ratelimited("Dropping name table update (%d) of {%u, %u, %u} from %s key=%u\n", 314 e->dtype, ntohl(e->i.type), 315 ntohl(e->i.lower), 316 ntohl(e->i.upper), 317 addr, ntohl(e->i.key)); 318 } 319 list_del(&e->next); 320 kfree(e); 321 } 322 } 323 324 /** 325 * tipc_named_rcv - process name table update messages sent by another node 326 */ 327 void tipc_named_rcv(struct net *net, struct sk_buff_head *inputq) 328 { 329 struct tipc_net *tn = net_generic(net, tipc_net_id); 330 struct tipc_msg *msg; 331 struct distr_item *item; 332 uint count; 333 u32 node; 334 struct sk_buff *skb; 335 int mtype; 336 337 spin_lock_bh(&tn->nametbl_lock); 338 for (skb = skb_dequeue(inputq); skb; skb = skb_dequeue(inputq)) { 339 skb_linearize(skb); 340 msg = buf_msg(skb); 341 mtype = msg_type(msg); 342 item = (struct distr_item *)msg_data(msg); 343 count = msg_data_sz(msg) / ITEM_SIZE; 344 node = msg_orignode(msg); 345 while (count--) { 346 if (!tipc_update_nametbl(net, item, node, mtype)) 347 tipc_named_add_backlog(item, mtype, node); 348 item++; 349 } 350 kfree_skb(skb); 351 tipc_named_process_backlog(net); 352 } 353 spin_unlock_bh(&tn->nametbl_lock); 354 } 355 356 /** 357 * tipc_named_reinit - re-initialize local publications 358 * 359 * This routine is called whenever TIPC networking is enabled. 360 * All name table entries published by this node are updated to reflect 361 * the node's new network address. 362 */ 363 void tipc_named_reinit(struct net *net) 364 { 365 struct tipc_net *tn = net_generic(net, tipc_net_id); 366 struct publication *publ; 367 int scope; 368 369 spin_lock_bh(&tn->nametbl_lock); 370 371 for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++) 372 list_for_each_entry_rcu(publ, &tn->nametbl->publ_list[scope], 373 local_list) 374 publ->node = tn->own_addr; 375 376 spin_unlock_bh(&tn->nametbl_lock); 377 } 378