Merge branch 'media_fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab...
[cris-mirror.git] / net / tipc / node.c
blob3af53e327f497e7d66d50c39fff00a19715a86e8
1 /*
2 * net/tipc/node.c: TIPC node management routines
4 * Copyright (c) 2000-2006, Ericsson AB
5 * Copyright (c) 2005-2006, Wind River Systems
6 * All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
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.
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.
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.
37 #include "core.h"
38 #include "config.h"
39 #include "node.h"
40 #include "name_distr.h"
42 static void node_lost_contact(struct tipc_node *n_ptr);
43 static void node_established_contact(struct tipc_node *n_ptr);
45 static DEFINE_SPINLOCK(node_create_lock);
47 u32 tipc_own_tag;
49 /**
50 * tipc_node_create - create neighboring node
52 * Currently, this routine is called by neighbor discovery code, which holds
53 * net_lock for reading only. We must take node_create_lock to ensure a node
54 * isn't created twice if two different bearers discover the node at the same
55 * time. (It would be preferable to switch to holding net_lock in write mode,
56 * but this is a non-trivial change.)
59 struct tipc_node *tipc_node_create(u32 addr)
61 struct tipc_node *n_ptr;
62 u32 n_num;
64 spin_lock_bh(&node_create_lock);
66 n_ptr = tipc_node_find(addr);
67 if (n_ptr) {
68 spin_unlock_bh(&node_create_lock);
69 return n_ptr;
72 n_ptr = kzalloc(sizeof(*n_ptr), GFP_ATOMIC);
73 if (!n_ptr) {
74 spin_unlock_bh(&node_create_lock);
75 warn("Node creation failed, no memory\n");
76 return NULL;
79 n_ptr->addr = addr;
80 spin_lock_init(&n_ptr->lock);
81 INIT_LIST_HEAD(&n_ptr->nsub);
83 n_num = tipc_node(addr);
84 tipc_net.nodes[n_num] = n_ptr;
85 if (n_num > tipc_net.highest_node)
86 tipc_net.highest_node = n_num;
88 spin_unlock_bh(&node_create_lock);
89 return n_ptr;
92 void tipc_node_delete(struct tipc_node *n_ptr)
94 u32 n_num;
96 if (!n_ptr)
97 return;
99 n_num = tipc_node(n_ptr->addr);
100 tipc_net.nodes[n_num] = NULL;
101 kfree(n_ptr);
103 while (!tipc_net.nodes[tipc_net.highest_node])
104 if (--tipc_net.highest_node == 0)
105 break;
110 * tipc_node_link_up - handle addition of link
112 * Link becomes active (alone or shared) or standby, depending on its priority.
115 void tipc_node_link_up(struct tipc_node *n_ptr, struct link *l_ptr)
117 struct link **active = &n_ptr->active_links[0];
119 n_ptr->working_links++;
121 info("Established link <%s> on network plane %c\n",
122 l_ptr->name, l_ptr->b_ptr->net_plane);
124 if (!active[0]) {
125 active[0] = active[1] = l_ptr;
126 node_established_contact(n_ptr);
127 return;
129 if (l_ptr->priority < active[0]->priority) {
130 info("New link <%s> becomes standby\n", l_ptr->name);
131 return;
133 tipc_link_send_duplicate(active[0], l_ptr);
134 if (l_ptr->priority == active[0]->priority) {
135 active[0] = l_ptr;
136 return;
138 info("Old link <%s> becomes standby\n", active[0]->name);
139 if (active[1] != active[0])
140 info("Old link <%s> becomes standby\n", active[1]->name);
141 active[0] = active[1] = l_ptr;
145 * node_select_active_links - select active link
148 static void node_select_active_links(struct tipc_node *n_ptr)
150 struct link **active = &n_ptr->active_links[0];
151 u32 i;
152 u32 highest_prio = 0;
154 active[0] = active[1] = NULL;
156 for (i = 0; i < MAX_BEARERS; i++) {
157 struct link *l_ptr = n_ptr->links[i];
159 if (!l_ptr || !tipc_link_is_up(l_ptr) ||
160 (l_ptr->priority < highest_prio))
161 continue;
163 if (l_ptr->priority > highest_prio) {
164 highest_prio = l_ptr->priority;
165 active[0] = active[1] = l_ptr;
166 } else {
167 active[1] = l_ptr;
173 * tipc_node_link_down - handle loss of link
176 void tipc_node_link_down(struct tipc_node *n_ptr, struct link *l_ptr)
178 struct link **active;
180 n_ptr->working_links--;
182 if (!tipc_link_is_active(l_ptr)) {
183 info("Lost standby link <%s> on network plane %c\n",
184 l_ptr->name, l_ptr->b_ptr->net_plane);
185 return;
187 info("Lost link <%s> on network plane %c\n",
188 l_ptr->name, l_ptr->b_ptr->net_plane);
190 active = &n_ptr->active_links[0];
191 if (active[0] == l_ptr)
192 active[0] = active[1];
193 if (active[1] == l_ptr)
194 active[1] = active[0];
195 if (active[0] == l_ptr)
196 node_select_active_links(n_ptr);
197 if (tipc_node_is_up(n_ptr))
198 tipc_link_changeover(l_ptr);
199 else
200 node_lost_contact(n_ptr);
203 int tipc_node_has_active_links(struct tipc_node *n_ptr)
205 return n_ptr->active_links[0] != NULL;
208 int tipc_node_has_redundant_links(struct tipc_node *n_ptr)
210 return n_ptr->working_links > 1;
213 int tipc_node_is_up(struct tipc_node *n_ptr)
215 return tipc_node_has_active_links(n_ptr);
218 struct tipc_node *tipc_node_attach_link(struct link *l_ptr)
220 struct tipc_node *n_ptr = tipc_node_find(l_ptr->addr);
222 if (!n_ptr)
223 n_ptr = tipc_node_create(l_ptr->addr);
224 if (n_ptr) {
225 u32 bearer_id = l_ptr->b_ptr->identity;
226 char addr_string[16];
228 if (n_ptr->link_cnt >= 2) {
229 err("Attempt to create third link to %s\n",
230 tipc_addr_string_fill(addr_string, n_ptr->addr));
231 return NULL;
234 if (!n_ptr->links[bearer_id]) {
235 n_ptr->links[bearer_id] = l_ptr;
236 tipc_net.links++;
237 n_ptr->link_cnt++;
238 return n_ptr;
240 err("Attempt to establish second link on <%s> to %s\n",
241 l_ptr->b_ptr->publ.name,
242 tipc_addr_string_fill(addr_string, l_ptr->addr));
244 return NULL;
247 void tipc_node_detach_link(struct tipc_node *n_ptr, struct link *l_ptr)
249 n_ptr->links[l_ptr->b_ptr->identity] = NULL;
250 tipc_net.links--;
251 n_ptr->link_cnt--;
255 * Routing table management - five cases to handle:
257 * 1: A link towards a zone/cluster external node comes up.
258 * => Send a multicast message updating routing tables of all
259 * system nodes within own cluster that the new destination
260 * can be reached via this node.
261 * (node.establishedContact()=>cluster.multicastNewRoute())
263 * 2: A link towards a slave node comes up.
264 * => Send a multicast message updating routing tables of all
265 * system nodes within own cluster that the new destination
266 * can be reached via this node.
267 * (node.establishedContact()=>cluster.multicastNewRoute())
268 * => Send a message to the slave node about existence
269 * of all system nodes within cluster:
270 * (node.establishedContact()=>cluster.sendLocalRoutes())
272 * 3: A new cluster local system node becomes available.
273 * => Send message(s) to this particular node containing
274 * information about all cluster external and slave
275 * nodes which can be reached via this node.
276 * (node.establishedContact()==>network.sendExternalRoutes())
277 * (node.establishedContact()==>network.sendSlaveRoutes())
278 * => Send messages to all directly connected slave nodes
279 * containing information about the existence of the new node
280 * (node.establishedContact()=>cluster.multicastNewRoute())
282 * 4: The link towards a zone/cluster external node or slave
283 * node goes down.
284 * => Send a multcast message updating routing tables of all
285 * nodes within cluster that the new destination can not any
286 * longer be reached via this node.
287 * (node.lostAllLinks()=>cluster.bcastLostRoute())
289 * 5: A cluster local system node becomes unavailable.
290 * => Remove all references to this node from the local
291 * routing tables. Note: This is a completely node
292 * local operation.
293 * (node.lostAllLinks()=>network.removeAsRouter())
294 * => Send messages to all directly connected slave nodes
295 * containing information about loss of the node
296 * (node.establishedContact()=>cluster.multicastLostRoute())
300 static void node_established_contact(struct tipc_node *n_ptr)
302 tipc_k_signal((Handler)tipc_named_node_up, n_ptr->addr);
304 /* Syncronize broadcast acks */
305 n_ptr->bclink.acked = tipc_bclink_get_last_sent();
307 if (n_ptr->bclink.supported) {
308 tipc_nmap_add(&tipc_bcast_nmap, n_ptr->addr);
309 if (n_ptr->addr < tipc_own_addr)
310 tipc_own_tag++;
314 static void node_cleanup_finished(unsigned long node_addr)
316 struct tipc_node *n_ptr;
318 read_lock_bh(&tipc_net_lock);
319 n_ptr = tipc_node_find(node_addr);
320 if (n_ptr) {
321 tipc_node_lock(n_ptr);
322 n_ptr->cleanup_required = 0;
323 tipc_node_unlock(n_ptr);
325 read_unlock_bh(&tipc_net_lock);
328 static void node_lost_contact(struct tipc_node *n_ptr)
330 struct tipc_node_subscr *ns, *tns;
331 char addr_string[16];
332 u32 i;
334 /* Clean up broadcast reception remains */
335 n_ptr->bclink.gap_after = n_ptr->bclink.gap_to = 0;
336 while (n_ptr->bclink.deferred_head) {
337 struct sk_buff *buf = n_ptr->bclink.deferred_head;
338 n_ptr->bclink.deferred_head = buf->next;
339 buf_discard(buf);
341 if (n_ptr->bclink.defragm) {
342 buf_discard(n_ptr->bclink.defragm);
343 n_ptr->bclink.defragm = NULL;
346 if (n_ptr->bclink.supported) {
347 tipc_bclink_acknowledge(n_ptr,
348 mod(n_ptr->bclink.acked + 10000));
349 tipc_nmap_remove(&tipc_bcast_nmap, n_ptr->addr);
350 if (n_ptr->addr < tipc_own_addr)
351 tipc_own_tag--;
354 info("Lost contact with %s\n",
355 tipc_addr_string_fill(addr_string, n_ptr->addr));
357 /* Abort link changeover */
358 for (i = 0; i < MAX_BEARERS; i++) {
359 struct link *l_ptr = n_ptr->links[i];
360 if (!l_ptr)
361 continue;
362 l_ptr->reset_checkpoint = l_ptr->next_in_no;
363 l_ptr->exp_msg_count = 0;
364 tipc_link_reset_fragments(l_ptr);
367 /* Notify subscribers */
368 list_for_each_entry_safe(ns, tns, &n_ptr->nsub, nodesub_list) {
369 ns->node = NULL;
370 list_del_init(&ns->nodesub_list);
371 tipc_k_signal((Handler)ns->handle_node_down,
372 (unsigned long)ns->usr_handle);
375 /* Prevent re-contact with node until all cleanup is done */
377 n_ptr->cleanup_required = 1;
378 tipc_k_signal((Handler)node_cleanup_finished, n_ptr->addr);
381 struct sk_buff *tipc_node_get_nodes(const void *req_tlv_area, int req_tlv_space)
383 u32 domain;
384 struct sk_buff *buf;
385 struct tipc_node *n_ptr;
386 struct tipc_node_info node_info;
387 u32 payload_size;
388 u32 n_num;
390 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
391 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
393 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));
394 if (!tipc_addr_domain_valid(domain))
395 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
396 " (network address)");
398 read_lock_bh(&tipc_net_lock);
399 if (!tipc_net.nodes) {
400 read_unlock_bh(&tipc_net_lock);
401 return tipc_cfg_reply_none();
404 /* For now, get space for all other nodes */
406 payload_size = TLV_SPACE(sizeof(node_info)) *
407 (tipc_net.highest_node - 1);
408 if (payload_size > 32768u) {
409 read_unlock_bh(&tipc_net_lock);
410 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
411 " (too many nodes)");
413 buf = tipc_cfg_reply_alloc(payload_size);
414 if (!buf) {
415 read_unlock_bh(&tipc_net_lock);
416 return NULL;
419 /* Add TLVs for all nodes in scope */
421 for (n_num = 1; n_num <= tipc_net.highest_node; n_num++) {
422 n_ptr = tipc_net.nodes[n_num];
423 if (!n_ptr || !tipc_in_scope(domain, n_ptr->addr))
424 continue;
425 node_info.addr = htonl(n_ptr->addr);
426 node_info.up = htonl(tipc_node_is_up(n_ptr));
427 tipc_cfg_append_tlv(buf, TIPC_TLV_NODE_INFO,
428 &node_info, sizeof(node_info));
431 read_unlock_bh(&tipc_net_lock);
432 return buf;
435 struct sk_buff *tipc_node_get_links(const void *req_tlv_area, int req_tlv_space)
437 u32 domain;
438 struct sk_buff *buf;
439 struct tipc_node *n_ptr;
440 struct tipc_link_info link_info;
441 u32 payload_size;
442 u32 n_num;
444 if (!TLV_CHECK(req_tlv_area, req_tlv_space, TIPC_TLV_NET_ADDR))
445 return tipc_cfg_reply_error_string(TIPC_CFG_TLV_ERROR);
447 domain = ntohl(*(__be32 *)TLV_DATA(req_tlv_area));
448 if (!tipc_addr_domain_valid(domain))
449 return tipc_cfg_reply_error_string(TIPC_CFG_INVALID_VALUE
450 " (network address)");
452 if (tipc_mode != TIPC_NET_MODE)
453 return tipc_cfg_reply_none();
455 read_lock_bh(&tipc_net_lock);
457 /* Get space for all unicast links + multicast link */
459 payload_size = TLV_SPACE(sizeof(link_info)) * (tipc_net.links + 1);
460 if (payload_size > 32768u) {
461 read_unlock_bh(&tipc_net_lock);
462 return tipc_cfg_reply_error_string(TIPC_CFG_NOT_SUPPORTED
463 " (too many links)");
465 buf = tipc_cfg_reply_alloc(payload_size);
466 if (!buf) {
467 read_unlock_bh(&tipc_net_lock);
468 return NULL;
471 /* Add TLV for broadcast link */
473 link_info.dest = htonl(tipc_own_addr & 0xfffff00);
474 link_info.up = htonl(1);
475 strlcpy(link_info.str, tipc_bclink_name, TIPC_MAX_LINK_NAME);
476 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO, &link_info, sizeof(link_info));
478 /* Add TLVs for any other links in scope */
480 for (n_num = 1; n_num <= tipc_net.highest_node; n_num++) {
481 u32 i;
483 n_ptr = tipc_net.nodes[n_num];
484 if (!n_ptr || !tipc_in_scope(domain, n_ptr->addr))
485 continue;
486 tipc_node_lock(n_ptr);
487 for (i = 0; i < MAX_BEARERS; i++) {
488 if (!n_ptr->links[i])
489 continue;
490 link_info.dest = htonl(n_ptr->addr);
491 link_info.up = htonl(tipc_link_is_up(n_ptr->links[i]));
492 strcpy(link_info.str, n_ptr->links[i]->name);
493 tipc_cfg_append_tlv(buf, TIPC_TLV_LINK_INFO,
494 &link_info, sizeof(link_info));
496 tipc_node_unlock(n_ptr);
499 read_unlock_bh(&tipc_net_lock);
500 return buf;