net/tipc/name_distr.c

   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 struct distr_queue_item {
  44         struct distr_item i;
  45         u32 dtype;
  46         u32 node;
  47         unsigned long expires;
  48         struct list_head next;
  49 };
  50
  51 /**
  52  * publ_to_item - add publication info to a publication message
  53  */
  54 static void publ_to_item(struct distr_item *i, struct publication *p)
  55 {
  56         i->type = htonl(p->type);
  57         i->lower = htonl(p->lower);
  58         i->upper = htonl(p->upper);
  59         i->ref = htonl(p->ref);
  60         i->key = htonl(p->key);
  61 }
  62
  63 /**
  64  * named_prepare_buf - allocate & initialize a publication message
  65  *
  66  * The buffer returned is of size INT_H_SIZE + payload size
  67  */
  68 static struct sk_buff *named_prepare_buf(struct net *net, u32 type, u32 size,
  69                                          u32 dest)
  70 {
  71         struct tipc_net *tn = net_generic(net, tipc_net_id);
  72         struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size);
  73         struct tipc_msg *msg;
  74
  75         if (buf != NULL) {
  76                 msg = buf_msg(buf);
  77                 tipc_msg_init(tn->own_addr, msg, NAME_DISTRIBUTOR, type,
  78                               INT_H_SIZE, dest);
  79                 msg_set_size(msg, INT_H_SIZE + size);
  80         }
  81         return buf;
  82 }
  83
  84 void named_cluster_distribute(struct net *net, struct sk_buff *skb)
  85 {
  86         struct tipc_net *tn = net_generic(net, tipc_net_id);
  87         struct sk_buff *oskb;
  88         struct tipc_node *node;
  89         u32 dnode;
  90
  91         rcu_read_lock();
  92         list_for_each_entry_rcu(node, &tn->node_list, list) {
  93                 dnode = node->addr;
  94                 if (in_own_node(net, dnode))
  95                         continue;
  96                 if (!tipc_node_is_up(node))
  97                         continue;
  98                 oskb = pskb_copy(skb, GFP_ATOMIC);
  99                 if (!oskb)
 100                         break;
 101                 msg_set_destnode(buf_msg(oskb), dnode);
 102                 tipc_node_xmit_skb(net, oskb, dnode, 0);
 103         }
 104         rcu_read_unlock();
 105
 106         kfree_skb(skb);
 107 }
 108
 109 /**
 110  * tipc_named_publish - tell other nodes about a new publication by this node
 111  */
 112 struct sk_buff *tipc_named_publish(struct net *net, struct publication *publ)
 113 {
 114         struct tipc_net *tn = net_generic(net, tipc_net_id);
 115         struct sk_buff *buf;
 116         struct distr_item *item;
 117
 118         list_add_tail_rcu(&publ->local_list,
 119                           &tn->nametbl->publ_list[publ->scope]);
 120
 121         if (publ->scope == TIPC_NODE_SCOPE)
 122                 return NULL;
 123
 124         buf = named_prepare_buf(net, PUBLICATION, ITEM_SIZE, 0);
 125         if (!buf) {
 126                 pr_warn("Publication distribution failure\n");
 127                 return NULL;
 128         }
 129
 130         item = (struct distr_item *)msg_data(buf_msg(buf));
 131         publ_to_item(item, publ);
 132         return buf;
 133 }
 134
 135 /**
 136  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
 137  */
 138 struct sk_buff *tipc_named_withdraw(struct net *net, struct publication *publ)
 139 {
 140         struct sk_buff *buf;
 141         struct distr_item *item;
 142
 143         list_del(&publ->local_list);
 144
 145         if (publ->scope == TIPC_NODE_SCOPE)
 146                 return NULL;
 147
 148         buf = named_prepare_buf(net, WITHDRAWAL, ITEM_SIZE, 0);
 149         if (!buf) {
 150                 pr_warn("Withdrawal distribution failure\n");
 151                 return NULL;
 152         }
 153
 154         item = (struct distr_item *)msg_data(buf_msg(buf));
 155         publ_to_item(item, publ);
 156         return buf;
 157 }
 158
 159 /**
 160  * named_distribute - prepare name info for bulk distribution to another node
 161  * @list: list of messages (buffers) to be returned from this function
 162  * @dnode: node to be updated
 163  * @pls: linked list of publication items to be packed into buffer chain
 164  */
 165 static void named_distribute(struct net *net, struct sk_buff_head *list,
 166                              u32 dnode, struct list_head *pls)
 167 {
 168         struct publication *publ;
 169         struct sk_buff *skb = NULL;
 170         struct distr_item *item = NULL;
 171         u32 msg_dsz = ((tipc_node_get_mtu(net, dnode, 0) - INT_H_SIZE) /
 172                         ITEM_SIZE) * ITEM_SIZE;
 173         u32 msg_rem = msg_dsz;
 174
 175         list_for_each_entry(publ, pls, local_list) {
 176                 /* Prepare next buffer: */
 177                 if (!skb) {
 178                         skb = named_prepare_buf(net, PUBLICATION, msg_rem,
 179                                                 dnode);
 180                         if (!skb) {
 181                                 pr_warn("Bulk publication failure\n");
 182                                 return;
 183                         }
 184                         item = (struct distr_item *)msg_data(buf_msg(skb));
 185                 }
 186
 187                 /* Pack publication into message: */
 188                 publ_to_item(item, publ);
 189                 item++;
 190                 msg_rem -= ITEM_SIZE;
 191
 192                 /* Append full buffer to list: */
 193                 if (!msg_rem) {
 194                         __skb_queue_tail(list, skb);
 195                         skb = NULL;
 196                         msg_rem = msg_dsz;
 197                 }
 198         }
 199         if (skb) {
 200                 msg_set_size(buf_msg(skb), INT_H_SIZE + (msg_dsz - msg_rem));
 201                 skb_trim(skb, INT_H_SIZE + (msg_dsz - msg_rem));
 202                 __skb_queue_tail(list, skb);
 203         }
 204 }
 205
 206 /**
 207  * tipc_named_node_up - tell specified node about all publications by this node
 208  */
 209 void tipc_named_node_up(struct net *net, u32 dnode)
 210 {
 211         struct tipc_net *tn = net_generic(net, tipc_net_id);
 212         struct sk_buff_head head;
 213
 214         __skb_queue_head_init(&head);
 215
 216         rcu_read_lock();
 217         named_distribute(net, &head, dnode,
 218                          &tn->nametbl->publ_list[TIPC_CLUSTER_SCOPE]);
 219         named_distribute(net, &head, dnode,
 220                          &tn->nametbl->publ_list[TIPC_ZONE_SCOPE]);
 221         rcu_read_unlock();
 222
 223         tipc_node_xmit(net, &head, dnode, 0);
 224 }
 225
 226 static void tipc_publ_subscribe(struct net *net, struct publication *publ,
 227                                 u32 addr)
 228 {
 229         struct tipc_node *node;
 230
 231         if (in_own_node(net, addr))
 232                 return;
 233
 234         node = tipc_node_find(net, addr);
 235         if (!node) {
 236                 pr_warn("Node subscription rejected, unknown node 0x%x\n",
 237                         addr);
 238                 return;
 239         }
 240
 241         tipc_node_lock(node);
 242         list_add_tail(&publ->nodesub_list, &node->publ_list);
 243         tipc_node_unlock(node);
 244         tipc_node_put(node);
 245 }
 246
 247 static void tipc_publ_unsubscribe(struct net *net, struct publication *publ,
 248                                   u32 addr)
 249 {
 250         struct tipc_node *node;
 251
 252         node = tipc_node_find(net, addr);
 253         if (!node)
 254                 return;
 255
 256         tipc_node_lock(node);
 257         list_del_init(&publ->nodesub_list);
 258         tipc_node_unlock(node);
 259         tipc_node_put(node);
 260 }
 261
 262 /**
 263  * tipc_publ_purge - remove publication associated with a failed node
 264  *
 265  * Invoked for each publication issued by a newly failed node.
 266  * Removes publication structure from name table & deletes it.
 267  */
 268 static void tipc_publ_purge(struct net *net, struct publication *publ, u32 addr)
 269 {
 270         struct tipc_net *tn = net_generic(net, tipc_net_id);
 271         struct publication *p;
 272
 273         spin_lock_bh(&tn->nametbl_lock);
 274         p = tipc_nametbl_remove_publ(net, publ->type, publ->lower,
 275                                      publ->node, publ->ref, publ->key);
 276         if (p)
 277                 tipc_publ_unsubscribe(net, p, addr);
 278         spin_unlock_bh(&tn->nametbl_lock);
 279
 280         if (p != publ) {
 281                 pr_err("Unable to remove publication from failed node\n"
 282                        " (type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
 283                        publ->type, publ->lower, publ->node, publ->ref,
 284                        publ->key);
 285         }
 286
 287         kfree_rcu(p, rcu);
 288 }
 289
 290 void tipc_publ_notify(struct net *net, struct list_head *nsub_list, u32 addr)
 291 {
 292         struct publication *publ, *tmp;
 293
 294         list_for_each_entry_safe(publ, tmp, nsub_list, nodesub_list)
 295                 tipc_publ_purge(net, publ, addr);
 296 }
 297
 298 /**
 299  * tipc_update_nametbl - try to process a nametable update and notify
 300  *                       subscribers
 301  *
 302  * tipc_nametbl_lock must be held.
 303  * Returns the publication item if successful, otherwise NULL.
 304  */
 305 static bool tipc_update_nametbl(struct net *net, struct distr_item *i,
 306                                 u32 node, u32 dtype)
 307 {
 308         struct publication *publ = NULL;
 309
 310         if (dtype == PUBLICATION) {
 311                 publ = tipc_nametbl_insert_publ(net, ntohl(i->type),
 312                                                 ntohl(i->lower),
 313                                                 ntohl(i->upper),
 314                                                 TIPC_CLUSTER_SCOPE, node,
 315                                                 ntohl(i->ref), ntohl(i->key));
 316                 if (publ) {
 317                         tipc_publ_subscribe(net, publ, node);
 318                         return true;
 319                 }
 320         } else if (dtype == WITHDRAWAL) {
 321                 publ = tipc_nametbl_remove_publ(net, ntohl(i->type),
 322                                                 ntohl(i->lower),
 323                                                 node, ntohl(i->ref),
 324                                                 ntohl(i->key));
 325                 if (publ) {
 326                         tipc_publ_unsubscribe(net, publ, node);
 327                         kfree_rcu(publ, rcu);
 328                         return true;
 329                 }
 330         } else {
 331                 pr_warn("Unrecognized name table message received\n");
 332         }
 333         return false;
 334 }
 335
 336 /**
 337  * tipc_named_add_backlog - add a failed name table update to the backlog
 338  *
 339  */
 340 static void tipc_named_add_backlog(struct net *net, struct distr_item *i,
 341                                    u32 type, u32 node)
 342 {
 343         struct distr_queue_item *e;
 344         struct tipc_net *tn = net_generic(net, tipc_net_id);
 345         unsigned long now = get_jiffies_64();
 346
 347         e = kzalloc(sizeof(*e), GFP_ATOMIC);
 348         if (!e)
 349                 return;
 350         e->dtype = type;
 351         e->node = node;
 352         e->expires = now + msecs_to_jiffies(sysctl_tipc_named_timeout);
 353         memcpy(e, i, sizeof(*i));
 354         list_add_tail(&e->next, &tn->dist_queue);
 355 }
 356
 357 /**
 358  * tipc_named_process_backlog - try to process any pending name table updates
 359  * from the network.
 360  */
 361 void tipc_named_process_backlog(struct net *net)
 362 {
 363         struct distr_queue_item *e, *tmp;
 364         struct tipc_net *tn = net_generic(net, tipc_net_id);
 365         char addr[16];
 366         unsigned long now = get_jiffies_64();
 367
 368         list_for_each_entry_safe(e, tmp, &tn->dist_queue, next) {
 369                 if (time_after(e->expires, now)) {
 370                         if (!tipc_update_nametbl(net, &e->i, e->node, e->dtype))
 371                                 continue;
 372                 } else {
 373                         tipc_addr_string_fill(addr, e->node);
 374                         pr_warn_ratelimited("Dropping name table update (%d) of {%u, %u, %u} from %s key=%u\n",
 375                                             e->dtype, ntohl(e->i.type),
 376                                             ntohl(e->i.lower),
 377                                             ntohl(e->i.upper),
 378                                             addr, ntohl(e->i.key));
 379                 }
 380                 list_del(&e->next);
 381                 kfree(e);
 382         }
 383 }
 384
 385 /**
 386  * tipc_named_rcv - process name table update messages sent by another node
 387  */
 388 void tipc_named_rcv(struct net *net, struct sk_buff_head *inputq)
 389 {
 390         struct tipc_net *tn = net_generic(net, tipc_net_id);
 391         struct tipc_msg *msg;
 392         struct distr_item *item;
 393         uint count;
 394         u32 node;
 395         struct sk_buff *skb;
 396         int mtype;
 397
 398         spin_lock_bh(&tn->nametbl_lock);
 399         for (skb = skb_dequeue(inputq); skb; skb = skb_dequeue(inputq)) {
 400                 skb_linearize(skb);
 401                 msg = buf_msg(skb);
 402                 mtype = msg_type(msg);
 403                 item = (struct distr_item *)msg_data(msg);
 404                 count = msg_data_sz(msg) / ITEM_SIZE;
 405                 node = msg_orignode(msg);
 406                 while (count--) {
 407                         if (!tipc_update_nametbl(net, item, node, mtype))
 408                                 tipc_named_add_backlog(net, item, mtype, node);
 409                         item++;
 410                 }
 411                 kfree_skb(skb);
 412                 tipc_named_process_backlog(net);
 413         }
 414         spin_unlock_bh(&tn->nametbl_lock);
 415 }
 416
 417 /**
 418  * tipc_named_reinit - re-initialize local publications
 419  *
 420  * This routine is called whenever TIPC networking is enabled.
 421  * All name table entries published by this node are updated to reflect
 422  * the node's new network address.
 423  */
 424 void tipc_named_reinit(struct net *net)
 425 {
 426         struct tipc_net *tn = net_generic(net, tipc_net_id);
 427         struct publication *publ;
 428         int scope;
 429
 430         spin_lock_bh(&tn->nametbl_lock);
 431
 432         for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++)
 433                 list_for_each_entry_rcu(publ, &tn->nametbl->publ_list[scope],
 434                                         local_list)
 435                         publ->node = tn->own_addr;
 436
 437         spin_unlock_bh(&tn->nametbl_lock);
 438 }