net/tipc/name_distr.c

   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 /**
  42  * struct publ_list - list of publications made by this node
  43  * @list: circular list of publications
  44  * @list_size: number of entries in list
  45  */
  46 struct publ_list {
  47         struct list_head list;
  48         u32 size;
  49 };
  50
  51 static struct publ_list publ_zone = {
  52         .list = LIST_HEAD_INIT(publ_zone.list),
  53         .size = 0,
  54 };
  55
  56 static struct publ_list publ_cluster = {
  57         .list = LIST_HEAD_INIT(publ_cluster.list),
  58         .size = 0,
  59 };
  60
  61 static struct publ_list publ_node = {
  62         .list = LIST_HEAD_INIT(publ_node.list),
  63         .size = 0,
  64 };
  65
  66 static struct publ_list *publ_lists[] = {
  67         NULL,
  68         &publ_zone,     /* publ_lists[TIPC_ZONE_SCOPE]          */
  69         &publ_cluster,  /* publ_lists[TIPC_CLUSTER_SCOPE]       */
  70         &publ_node      /* publ_lists[TIPC_NODE_SCOPE]          */
  71 };
  72
  73
  74 /**
  75  * publ_to_item - add publication info to a publication message
  76  */
  77 static void publ_to_item(struct distr_item *i, struct publication *p)
  78 {
  79         i->type = htonl(p->type);
  80         i->lower = htonl(p->lower);
  81         i->upper = htonl(p->upper);
  82         i->ref = htonl(p->ref);
  83         i->key = htonl(p->key);
  84 }
  85
  86 /**
  87  * named_prepare_buf - allocate & initialize a publication message
  88  */
  89 static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
  90 {
  91         struct sk_buff *buf = tipc_buf_acquire(INT_H_SIZE + size);
  92         struct tipc_msg *msg;
  93
  94         if (buf != NULL) {
  95                 msg = buf_msg(buf);
  96                 tipc_msg_init(msg, NAME_DISTRIBUTOR, type, INT_H_SIZE, dest);
  97                 msg_set_size(msg, INT_H_SIZE + size);
  98         }
  99         return buf;
 100 }
 101
 102 void named_cluster_distribute(struct sk_buff *buf)
 103 {
 104         struct sk_buff *buf_copy;
 105         struct tipc_node *n_ptr;
 106         struct tipc_link *l_ptr;
 107
 108         rcu_read_lock();
 109         list_for_each_entry_rcu(n_ptr, &tipc_node_list, list) {
 110                 tipc_node_lock(n_ptr);
 111                 l_ptr = n_ptr->active_links[n_ptr->addr & 1];
 112                 if (l_ptr) {
 113                         buf_copy = skb_copy(buf, GFP_ATOMIC);
 114                         if (!buf_copy) {
 115                                 tipc_node_unlock(n_ptr);
 116                                 break;
 117                         }
 118                         msg_set_destnode(buf_msg(buf_copy), n_ptr->addr);
 119                         __tipc_link_xmit(l_ptr, buf_copy);
 120                 }
 121                 tipc_node_unlock(n_ptr);
 122         }
 123         rcu_read_unlock();
 124
 125         kfree_skb(buf);
 126 }
 127
 128 /**
 129  * tipc_named_publish - tell other nodes about a new publication by this node
 130  */
 131 struct sk_buff *tipc_named_publish(struct publication *publ)
 132 {
 133         struct sk_buff *buf;
 134         struct distr_item *item;
 135
 136         list_add_tail(&publ->local_list, &publ_lists[publ->scope]->list);
 137         publ_lists[publ->scope]->size++;
 138
 139         if (publ->scope == TIPC_NODE_SCOPE)
 140                 return NULL;
 141
 142         buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
 143         if (!buf) {
 144                 pr_warn("Publication distribution failure\n");
 145                 return NULL;
 146         }
 147
 148         item = (struct distr_item *)msg_data(buf_msg(buf));
 149         publ_to_item(item, publ);
 150         return buf;
 151 }
 152
 153 /**
 154  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
 155  */
 156 struct sk_buff *tipc_named_withdraw(struct publication *publ)
 157 {
 158         struct sk_buff *buf;
 159         struct distr_item *item;
 160
 161         list_del(&publ->local_list);
 162         publ_lists[publ->scope]->size--;
 163
 164         if (publ->scope == TIPC_NODE_SCOPE)
 165                 return NULL;
 166
 167         buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
 168         if (!buf) {
 169                 pr_warn("Withdrawal distribution failure\n");
 170                 return NULL;
 171         }
 172
 173         item = (struct distr_item *)msg_data(buf_msg(buf));
 174         publ_to_item(item, publ);
 175         return buf;
 176 }
 177
 178 /*
 179  * named_distribute - prepare name info for bulk distribution to another node
 180  */
 181 static void named_distribute(struct list_head *message_list, u32 node,
 182                              struct publ_list *pls, u32 max_item_buf)
 183 {
 184         struct publication *publ;
 185         struct sk_buff *buf = NULL;
 186         struct distr_item *item = NULL;
 187         u32 left = 0;
 188         u32 rest = pls->size * ITEM_SIZE;
 189
 190         list_for_each_entry(publ, &pls->list, local_list) {
 191                 if (!buf) {
 192                         left = (rest <= max_item_buf) ? rest : max_item_buf;
 193                         rest -= left;
 194                         buf = named_prepare_buf(PUBLICATION, left, node);
 195                         if (!buf) {
 196                                 pr_warn("Bulk publication failure\n");
 197                                 return;
 198                         }
 199                         item = (struct distr_item *)msg_data(buf_msg(buf));
 200                 }
 201                 publ_to_item(item, publ);
 202                 item++;
 203                 left -= ITEM_SIZE;
 204                 if (!left) {
 205                         list_add_tail((struct list_head *)buf, message_list);
 206                         buf = NULL;
 207                 }
 208         }
 209 }
 210
 211 /**
 212  * tipc_named_node_up - tell specified node about all publications by this node
 213  */
 214 void tipc_named_node_up(u32 max_item_buf, u32 node)
 215 {
 216         LIST_HEAD(message_list);
 217
 218         read_lock_bh(&tipc_nametbl_lock);
 219         named_distribute(&message_list, node, &publ_cluster, max_item_buf);
 220         named_distribute(&message_list, node, &publ_zone, max_item_buf);
 221         read_unlock_bh(&tipc_nametbl_lock);
 222
 223         tipc_link_names_xmit(&message_list, node);
 224 }
 225
 226 /**
 227  * named_purge_publ - remove publication associated with a failed node
 228  *
 229  * Invoked for each publication issued by a newly failed node.
 230  * Removes publication structure from name table & deletes it.
 231  */
 232 static void named_purge_publ(struct publication *publ)
 233 {
 234         struct publication *p;
 235
 236         write_lock_bh(&tipc_nametbl_lock);
 237         p = tipc_nametbl_remove_publ(publ->type, publ->lower,
 238                                      publ->node, publ->ref, publ->key);
 239         if (p)
 240                 tipc_nodesub_unsubscribe(&p->subscr);
 241         write_unlock_bh(&tipc_nametbl_lock);
 242
 243         if (p != publ) {
 244                 pr_err("Unable to remove publication from failed node\n"
 245                        " (type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
 246                        publ->type, publ->lower, publ->node, publ->ref,
 247                        publ->key);
 248         }
 249
 250         kfree(p);
 251 }
 252
 253 /**
 254  * tipc_named_rcv - process name table update message sent by another node
 255  */
 256 void tipc_named_rcv(struct sk_buff *buf)
 257 {
 258         struct publication *publ;
 259         struct tipc_msg *msg = buf_msg(buf);
 260         struct distr_item *item = (struct distr_item *)msg_data(msg);
 261         u32 count = msg_data_sz(msg) / ITEM_SIZE;
 262
 263         write_lock_bh(&tipc_nametbl_lock);
 264         while (count--) {
 265                 if (msg_type(msg) == PUBLICATION) {
 266                         publ = tipc_nametbl_insert_publ(ntohl(item->type),
 267                                                         ntohl(item->lower),
 268                                                         ntohl(item->upper),
 269                                                         TIPC_CLUSTER_SCOPE,
 270                                                         msg_orignode(msg),
 271                                                         ntohl(item->ref),
 272                                                         ntohl(item->key));
 273                         if (publ) {
 274                                 tipc_nodesub_subscribe(&publ->subscr,
 275                                                        msg_orignode(msg),
 276                                                        publ,
 277                                                        (net_ev_handler)
 278                                                        named_purge_publ);
 279                         }
 280                 } else if (msg_type(msg) == WITHDRAWAL) {
 281                         publ = tipc_nametbl_remove_publ(ntohl(item->type),
 282                                                         ntohl(item->lower),
 283                                                         msg_orignode(msg),
 284                                                         ntohl(item->ref),
 285                                                         ntohl(item->key));
 286
 287                         if (publ) {
 288                                 tipc_nodesub_unsubscribe(&publ->subscr);
 289                                 kfree(publ);
 290                         } else {
 291                                 pr_err("Unable to remove publication by node 0x%x\n"
 292                                        " (type=%u, lower=%u, ref=%u, key=%u)\n",
 293                                        msg_orignode(msg), ntohl(item->type),
 294                                        ntohl(item->lower), ntohl(item->ref),
 295                                        ntohl(item->key));
 296                         }
 297                 } else {
 298                         pr_warn("Unrecognized name table message received\n");
 299                 }
 300                 item++;
 301         }
 302         write_unlock_bh(&tipc_nametbl_lock);
 303         kfree_skb(buf);
 304 }
 305
 306 /**
 307  * tipc_named_reinit - re-initialize local publications
 308  *
 309  * This routine is called whenever TIPC networking is enabled.
 310  * All name table entries published by this node are updated to reflect
 311  * the node's new network address.
 312  */
 313 void tipc_named_reinit(void)
 314 {
 315         struct publication *publ;
 316         int scope;
 317
 318         write_lock_bh(&tipc_nametbl_lock);
 319
 320         for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++)
 321                 list_for_each_entry(publ, &publ_lists[scope]->list, local_list)
 322                         publ->node = tipc_own_addr;
 323
 324         write_unlock_bh(&tipc_nametbl_lock);
 325 }