[NET] TIPC: Fix whitespace errors.
[linux-2.6.git] / 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, 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 "cluster.h"
39 #include "dbg.h"
40 #include "link.h"
41 #include "msg.h"
42 #include "name_distr.h"
43
44 #undef  DBG_OUTPUT
45 #define DBG_OUTPUT NULL
46
47 #define ITEM_SIZE sizeof(struct distr_item)
48
49 /**
50  * struct distr_item - publication info distributed to other nodes
51  * @type: name sequence type
52  * @lower: name sequence lower bound
53  * @upper: name sequence upper bound
54  * @ref: publishing port reference
55  * @key: publication key
56  *
57  * ===> All fields are stored in network byte order. <===
58  *
59  * First 3 fields identify (name or) name sequence being published.
60  * Reference field uniquely identifies port that published name sequence.
61  * Key field uniquely identifies publication, in the event a port has
62  * multiple publications of the same name sequence.
63  *
64  * Note: There is no field that identifies the publishing node because it is
65  * the same for all items contained within a publication message.
66  */
67
68 struct distr_item {
69         __be32 type;
70         __be32 lower;
71         __be32 upper;
72         __be32 ref;
73         __be32 key;
74 };
75
76 /**
77  * List of externally visible publications by this node --
78  * that is, all publications having scope > TIPC_NODE_SCOPE.
79  */
80
81 static LIST_HEAD(publ_root);
82 static u32 publ_cnt = 0;
83
84 /**
85  * publ_to_item - add publication info to a publication message
86  */
87
88 static void publ_to_item(struct distr_item *i, struct publication *p)
89 {
90         i->type = htonl(p->type);
91         i->lower = htonl(p->lower);
92         i->upper = htonl(p->upper);
93         i->ref = htonl(p->ref);
94         i->key = htonl(p->key);
95         dbg("publ_to_item: %u, %u, %u\n", p->type, p->lower, p->upper);
96 }
97
98 /**
99  * named_prepare_buf - allocate & initialize a publication message
100  */
101
102 static struct sk_buff *named_prepare_buf(u32 type, u32 size, u32 dest)
103 {
104         struct sk_buff *buf = buf_acquire(LONG_H_SIZE + size);
105         struct tipc_msg *msg;
106
107         if (buf != NULL) {
108                 msg = buf_msg(buf);
109                 msg_init(msg, NAME_DISTRIBUTOR, type, TIPC_OK,
110                          LONG_H_SIZE, dest);
111                 msg_set_size(msg, LONG_H_SIZE + size);
112         }
113         return buf;
114 }
115
116 /**
117  * tipc_named_publish - tell other nodes about a new publication by this node
118  */
119
120 void tipc_named_publish(struct publication *publ)
121 {
122         struct sk_buff *buf;
123         struct distr_item *item;
124
125         list_add_tail(&publ->local_list, &publ_root);
126         publ_cnt++;
127
128         buf = named_prepare_buf(PUBLICATION, ITEM_SIZE, 0);
129         if (!buf) {
130                 warn("Publication distribution failure\n");
131                 return;
132         }
133
134         item = (struct distr_item *)msg_data(buf_msg(buf));
135         publ_to_item(item, publ);
136         dbg("tipc_named_withdraw: broadcasting publish msg\n");
137         tipc_cltr_broadcast(buf);
138 }
139
140 /**
141  * tipc_named_withdraw - tell other nodes about a withdrawn publication by this node
142  */
143
144 void tipc_named_withdraw(struct publication *publ)
145 {
146         struct sk_buff *buf;
147         struct distr_item *item;
148
149         list_del(&publ->local_list);
150         publ_cnt--;
151
152         buf = named_prepare_buf(WITHDRAWAL, ITEM_SIZE, 0);
153         if (!buf) {
154                 warn("Withdrawl distribution failure\n");
155                 return;
156         }
157
158         item = (struct distr_item *)msg_data(buf_msg(buf));
159         publ_to_item(item, publ);
160         dbg("tipc_named_withdraw: broadcasting withdraw msg\n");
161         tipc_cltr_broadcast(buf);
162 }
163
164 /**
165  * tipc_named_node_up - tell specified node about all publications by this node
166  */
167
168 void tipc_named_node_up(unsigned long node)
169 {
170         struct publication *publ;
171         struct distr_item *item = NULL;
172         struct sk_buff *buf = NULL;
173         u32 left = 0;
174         u32 rest;
175         u32 max_item_buf;
176
177         read_lock_bh(&tipc_nametbl_lock);
178         max_item_buf = TIPC_MAX_USER_MSG_SIZE / ITEM_SIZE;
179         max_item_buf *= ITEM_SIZE;
180         rest = publ_cnt * ITEM_SIZE;
181
182         list_for_each_entry(publ, &publ_root, local_list) {
183                 if (!buf) {
184                         left = (rest <= max_item_buf) ? rest : max_item_buf;
185                         rest -= left;
186                         buf = named_prepare_buf(PUBLICATION, left, node);
187                         if (!buf) {
188                                 warn("Bulk publication distribution failure\n");
189                                 goto exit;
190                         }
191                         item = (struct distr_item *)msg_data(buf_msg(buf));
192                 }
193                 publ_to_item(item, publ);
194                 item++;
195                 left -= ITEM_SIZE;
196                 if (!left) {
197                         msg_set_link_selector(buf_msg(buf), node);
198                         dbg("tipc_named_node_up: sending publish msg to "
199                             "<%u.%u.%u>\n", tipc_zone(node),
200                             tipc_cluster(node), tipc_node(node));
201                         tipc_link_send(buf, node, node);
202                         buf = NULL;
203                 }
204         }
205 exit:
206         read_unlock_bh(&tipc_nametbl_lock);
207 }
208
209 /**
210  * node_is_down - remove publication associated with a failed node
211  *
212  * Invoked for each publication issued by a newly failed node.
213  * Removes publication structure from name table & deletes it.
214  * In rare cases the link may have come back up again when this
215  * function is called, and we have two items representing the same
216  * publication. Nudge this item's key to distinguish it from the other.
217  * (Note: Publication's node subscription is already unsubscribed.)
218  */
219
220 static void node_is_down(struct publication *publ)
221 {
222         struct publication *p;
223
224         write_lock_bh(&tipc_nametbl_lock);
225         dbg("node_is_down: withdrawing %u, %u, %u\n",
226             publ->type, publ->lower, publ->upper);
227         publ->key += 1222345;
228         p = tipc_nametbl_remove_publ(publ->type, publ->lower,
229                                      publ->node, publ->ref, publ->key);
230         write_unlock_bh(&tipc_nametbl_lock);
231
232         if (p != publ) {
233                 err("Unable to remove publication from failed node\n"
234                     "(type=%u, lower=%u, node=0x%x, ref=%u, key=%u)\n",
235                     publ->type, publ->lower, publ->node, publ->ref, publ->key);
236         }
237
238         if (p) {
239                 kfree(p);
240         }
241 }
242
243 /**
244  * tipc_named_recv - process name table update message sent by another node
245  */
246
247 void tipc_named_recv(struct sk_buff *buf)
248 {
249         struct publication *publ;
250         struct tipc_msg *msg = buf_msg(buf);
251         struct distr_item *item = (struct distr_item *)msg_data(msg);
252         u32 count = msg_data_sz(msg) / ITEM_SIZE;
253
254         write_lock_bh(&tipc_nametbl_lock);
255         while (count--) {
256                 if (msg_type(msg) == PUBLICATION) {
257                         dbg("tipc_named_recv: got publication for %u, %u, %u\n",
258                             ntohl(item->type), ntohl(item->lower),
259                             ntohl(item->upper));
260                         publ = tipc_nametbl_insert_publ(ntohl(item->type),
261                                                         ntohl(item->lower),
262                                                         ntohl(item->upper),
263                                                         TIPC_CLUSTER_SCOPE,
264                                                         msg_orignode(msg),
265                                                         ntohl(item->ref),
266                                                         ntohl(item->key));
267                         if (publ) {
268                                 tipc_nodesub_subscribe(&publ->subscr,
269                                                        msg_orignode(msg),
270                                                        publ,
271                                                        (net_ev_handler)node_is_down);
272                         }
273                 } else if (msg_type(msg) == WITHDRAWAL) {
274                         dbg("tipc_named_recv: got withdrawl for %u, %u, %u\n",
275                             ntohl(item->type), ntohl(item->lower),
276                             ntohl(item->upper));
277                         publ = tipc_nametbl_remove_publ(ntohl(item->type),
278                                                         ntohl(item->lower),
279                                                         msg_orignode(msg),
280                                                         ntohl(item->ref),
281                                                         ntohl(item->key));
282
283                         if (publ) {
284                                 tipc_nodesub_unsubscribe(&publ->subscr);
285                                 kfree(publ);
286                         } else {
287                                 err("Unable to remove publication by node 0x%x\n"
288                                     "(type=%u, lower=%u, ref=%u, key=%u)\n",
289                                     msg_orignode(msg),
290                                     ntohl(item->type), ntohl(item->lower),
291                                     ntohl(item->ref), ntohl(item->key));
292                         }
293                 } else {
294                         warn("Unrecognized name table message received\n");
295                 }
296                 item++;
297         }
298         write_unlock_bh(&tipc_nametbl_lock);
299         buf_discard(buf);
300 }
301
302 /**
303  * tipc_named_reinit - re-initialize local publication list
304  *
305  * This routine is called whenever TIPC networking is (re)enabled.
306  * All existing publications by this node that have "cluster" or "zone" scope
307  * are updated to reflect the node's current network address.
308  * (If the node's address is unchanged, the update loop terminates immediately.)
309  */
310
311 void tipc_named_reinit(void)
312 {
313         struct publication *publ;
314
315         write_lock_bh(&tipc_nametbl_lock);
316         list_for_each_entry(publ, &publ_root, local_list) {
317                 if (publ->node == tipc_own_addr)
318                         break;
319                 publ->node = tipc_own_addr;
320         }
321         write_unlock_bh(&tipc_nametbl_lock);
322 }