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 *obuf;
 105         struct tipc_node *node;
 106         u32 dnode;
 107
 108         rcu_read_lock();
 109         list_for_each_entry_rcu(node, &tipc_node_list, list) {
 110                 dnode = node->addr;
 111                 if (in_own_node(dnode))
 112                         continue;
 113                 if (!tipc_node_active_links(node))
 114                         continue;
 115                 obuf = skb_copy(buf, GFP_ATOMIC);
 116                 if (!obuf)
 117                         break;
 118                 msg_set_destnode(buf_msg(obuf), dnode);
 119                 tipc_link_xmit(obuf, dnode, dnode);
 120         }
 121         rcu_read_unlock();
 122
 123         kfree_skb(buf);
 124 }
 125
 126 /**
 127  * tipc_named_publish - tell other nodes about a new publication by this node
 128  */
 129 struct sk_buff *tipc_named_publish(struct publication *publ)
 130 {
 131         struct sk_buff *buf;
 132         struct distr_item *item;
 133
 134         list_add_tail(&publ->local_list, &publ_lists[publ->scope]->list);
 135         publ_lists[publ->scope]->size++;
 136
 137         if (publ->scope == TIPC_NODE_SCOPE)
 138                 return NULL;
 139
 140         buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
 141         if (!buf) {
 142                 pr_warn("Publication distribution failure\n");
 143                 return NULL;
 144         }
 145
 146         item = (struct distr_item *)msg_data(buf_msg(buf));
 147         publ_to_item(item, publ);
 148         return buf;
 149 }
 150
 151 /**
 152  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
 153  */
 154 struct sk_buff *tipc_named_withdraw(struct publication *publ)
 155 {
 156         struct sk_buff *buf;
 157         struct distr_item *item;
 158
 159         list_del(&publ->local_list);
 160         publ_lists[publ->scope]->size--;
 161
 162         if (publ->scope == TIPC_NODE_SCOPE)
 163                 return NULL;
 164
 165         buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
 166         if (!buf) {
 167                 pr_warn("Withdrawal distribution failure\n");
 168                 return NULL;
 169         }
 170
 171         item = (struct distr_item *)msg_data(buf_msg(buf));
 172         publ_to_item(item, publ);
 173         return buf;
 174 }
 175
 176 /**
 177  * named_distribute - prepare name info for bulk distribution to another node
 178  * @msg_list: list of messages (buffers) to be returned from this function
 179  * @dnode: node to be updated
 180  * @pls: linked list of publication items to be packed into buffer chain
 181  */
 182 static void named_distribute(struct list_head *msg_list, u32 dnode,
 183                              struct publ_list *pls)
 184 {
 185         struct publication *publ;
 186         struct sk_buff *buf = NULL;
 187         struct distr_item *item = NULL;
 188         uint dsz = pls->size * ITEM_SIZE;
 189         uint msg_dsz = (tipc_node_get_mtu(dnode, 0) / ITEM_SIZE) * ITEM_SIZE;
 190         uint rem = dsz;
 191         uint msg_rem = 0;
 192
 193         list_for_each_entry(publ, &pls->list, local_list) {
 194                 /* Prepare next buffer: */
 195                 if (!buf) {
 196                         msg_rem = min_t(uint, rem, msg_dsz);
 197                         rem -= msg_rem;
 198                         buf = named_prepare_buf(PUBLICATION, msg_rem, dnode);
 199                         if (!buf) {
 200                                 pr_warn("Bulk publication failure\n");
 201                                 return;
 202                         }
 203                         item = (struct distr_item *)msg_data(buf_msg(buf));
 204                 }
 205
 206                 /* Pack publication into message: */
 207                 publ_to_item(item, publ);
 208                 item++;
 209                 msg_rem -= ITEM_SIZE;
 210
 211                 /* Append full buffer to list: */
 212                 if (!msg_rem) {
 213                         list_add_tail((struct list_head *)buf, msg_list);
 214                         buf = NULL;
 215                 }
 216         }
 217 }
 218
 219 /**
 220  * tipc_named_node_up - tell specified node about all publications by this node
 221  */
 222 void tipc_named_node_up(u32 dnode)
 223 {
 224         LIST_HEAD(msg_list);
 225         struct sk_buff *buf_chain;
 226
 227         read_lock_bh(&tipc_nametbl_lock);
 228         named_distribute(&msg_list, dnode, &publ_cluster);
 229         named_distribute(&msg_list, dnode, &publ_zone);
 230         read_unlock_bh(&tipc_nametbl_lock);
 231
 232         /* Convert circular list to linear list and send: */
 233         buf_chain = (struct sk_buff *)msg_list.next;
 234         ((struct sk_buff *)msg_list.prev)->next = NULL;
 235         tipc_link_xmit(buf_chain, dnode, dnode);
 236 }
 237
 238 /**
 239  * named_purge_publ - remove publication associated with a failed node
 240  *
 241  * Invoked for each publication issued by a newly failed node.
 242  * Removes publication structure from name table & deletes it.
 243  */
 244 static void named_purge_publ(struct publication *publ)
 245 {
 246         struct publication *p;
 247
 248         write_lock_bh(&tipc_nametbl_lock);
 249         p = tipc_nametbl_remove_publ(publ->type, publ->lower,
 250                                      publ->node, publ->ref, publ->key);
 251         if (p)
 252                 tipc_nodesub_unsubscribe(&p->subscr);
 253         write_unlock_bh(&tipc_nametbl_lock);
 254
 255         if (p != publ) {
 256                 pr_err("Unable to remove publication from failed node\n"
 257                        " (type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
 258                        publ->type, publ->lower, publ->node, publ->ref,
 259                        publ->key);
 260         }
 261
 262         kfree(p);
 263 }
 264
 265 /**
 266  * tipc_named_rcv - process name table update message sent by another node
 267  */
 268 void tipc_named_rcv(struct sk_buff *buf)
 269 {
 270         struct publication *publ;
 271         struct tipc_msg *msg = buf_msg(buf);
 272         struct distr_item *item = (struct distr_item *)msg_data(msg);
 273         u32 count = msg_data_sz(msg) / ITEM_SIZE;
 274
 275         write_lock_bh(&tipc_nametbl_lock);
 276         while (count--) {
 277                 if (msg_type(msg) == PUBLICATION) {
 278                         publ = tipc_nametbl_insert_publ(ntohl(item->type),
 279                                                         ntohl(item->lower),
 280                                                         ntohl(item->upper),
 281                                                         TIPC_CLUSTER_SCOPE,
 282                                                         msg_orignode(msg),
 283                                                         ntohl(item->ref),
 284                                                         ntohl(item->key));
 285                         if (publ) {
 286                                 tipc_nodesub_subscribe(&publ->subscr,
 287                                                        msg_orignode(msg),
 288                                                        publ,
 289                                                        (net_ev_handler)
 290                                                        named_purge_publ);
 291                         }
 292                 } else if (msg_type(msg) == WITHDRAWAL) {
 293                         publ = tipc_nametbl_remove_publ(ntohl(item->type),
 294                                                         ntohl(item->lower),
 295                                                         msg_orignode(msg),
 296                                                         ntohl(item->ref),
 297                                                         ntohl(item->key));
 298
 299                         if (publ) {
 300                                 tipc_nodesub_unsubscribe(&publ->subscr);
 301                                 kfree(publ);
 302                         } else {
 303                                 pr_err("Unable to remove publication by node 0x%x\n"
 304                                        " (type=%u, lower=%u, ref=%u, key=%u)\n",
 305                                        msg_orignode(msg), ntohl(item->type),
 306                                        ntohl(item->lower), ntohl(item->ref),
 307                                        ntohl(item->key));
 308                         }
 309                 } else {
 310                         pr_warn("Unrecognized name table message received\n");
 311                 }
 312                 item++;
 313         }
 314         write_unlock_bh(&tipc_nametbl_lock);
 315         kfree_skb(buf);
 316 }
 317
 318 /**
 319  * tipc_named_reinit - re-initialize local publications
 320  *
 321  * This routine is called whenever TIPC networking is enabled.
 322  * All name table entries published by this node are updated to reflect
 323  * the node's new network address.
 324  */
 325 void tipc_named_reinit(void)
 326 {
 327         struct publication *publ;
 328         int scope;
 329
 330         write_lock_bh(&tipc_nametbl_lock);
 331
 332         for (scope = TIPC_ZONE_SCOPE; scope <= TIPC_NODE_SCOPE; scope++)
 333                 list_for_each_entry(publ, &publ_lists[scope]->list, local_list)
 334                         publ->node = tipc_own_addr;
 335
 336         write_unlock_bh(&tipc_nametbl_lock);
 337 }