[PATCH] arch/alpha: Use ARRAY_SIZE macro
[pohmelfs.git] / net / tipc / discover.c
blobee94de92ae9916f9c53f3fcd7b46cb917005eba5
1 /*
2 * net/tipc/discover.c
3 *
4 * Copyright (c) 2003-2006, 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 "dbg.h"
39 #include "link.h"
40 #include "zone.h"
41 #include "discover.h"
42 #include "port.h"
43 #include "name_table.h"
45 #define TIPC_LINK_REQ_INIT 125 /* min delay during bearer start up */
46 #define TIPC_LINK_REQ_FAST 2000 /* normal delay if bearer has no links */
47 #define TIPC_LINK_REQ_SLOW 600000 /* normal delay if bearer has links */
49 #if 0
50 #define GET_NODE_INFO 300
51 #define GET_NODE_INFO_RESULT 301
52 #define FORWARD_LINK_PROBE 302
53 #define LINK_REQUEST_REJECTED 303
54 #define LINK_REQUEST_ACCEPTED 304
55 #define DROP_LINK_REQUEST 305
56 #define CHECK_LINK_COUNT 306
57 #endif
59 /*
60 * TODO: Most of the inter-cluster setup stuff should be
61 * rewritten, and be made conformant with specification.
62 */
65 /**
66 * struct link_req - information about an ongoing link setup request
67 * @bearer: bearer issuing requests
68 * @dest: destination address for request messages
69 * @buf: request message to be (repeatedly) sent
70 * @timer: timer governing period between requests
71 * @timer_intv: current interval between requests (in ms)
73 struct link_req {
74 struct bearer *bearer;
75 struct tipc_media_addr dest;
76 struct sk_buff *buf;
77 struct timer_list timer;
78 unsigned int timer_intv;
82 #if 0
83 int disc_create_link(const struct tipc_link_create *argv)
85 /*
86 * Code for inter cluster link setup here
88 return TIPC_OK;
90 #endif
93 * disc_lost_link(): A link has lost contact
96 void tipc_disc_link_event(u32 addr, char *name, int up)
98 if (in_own_cluster(addr))
99 return;
101 * Code for inter cluster link setup here
105 /**
106 * tipc_disc_init_msg - initialize a link setup message
107 * @type: message type (request or response)
108 * @req_links: number of links associated with message
109 * @dest_domain: network domain of node(s) which should respond to message
110 * @b_ptr: ptr to bearer issuing message
113 static struct sk_buff *tipc_disc_init_msg(u32 type,
114 u32 req_links,
115 u32 dest_domain,
116 struct bearer *b_ptr)
118 struct sk_buff *buf = buf_acquire(DSC_H_SIZE);
119 struct tipc_msg *msg;
121 if (buf) {
122 msg = buf_msg(buf);
123 msg_init(msg, LINK_CONFIG, type, TIPC_OK, DSC_H_SIZE,
124 dest_domain);
125 msg_set_non_seq(msg);
126 msg_set_req_links(msg, req_links);
127 msg_set_dest_domain(msg, dest_domain);
128 msg_set_bc_netid(msg, tipc_net_id);
129 msg_set_media_addr(msg, &b_ptr->publ.addr);
131 return buf;
135 * tipc_disc_recv_msg - handle incoming link setup message (request or response)
136 * @buf: buffer containing message
139 void tipc_disc_recv_msg(struct sk_buff *buf)
141 struct bearer *b_ptr = (struct bearer *)TIPC_SKB_CB(buf)->handle;
142 struct link *link;
143 struct tipc_media_addr media_addr;
144 struct tipc_msg *msg = buf_msg(buf);
145 u32 dest = msg_dest_domain(msg);
146 u32 orig = msg_prevnode(msg);
147 u32 net_id = msg_bc_netid(msg);
148 u32 type = msg_type(msg);
150 msg_get_media_addr(msg,&media_addr);
151 msg_dbg(msg, "RECV:");
152 buf_discard(buf);
154 if (net_id != tipc_net_id)
155 return;
156 if (!tipc_addr_domain_valid(dest))
157 return;
158 if (!tipc_addr_node_valid(orig))
159 return;
160 if (orig == tipc_own_addr)
161 return;
162 if (!in_scope(dest, tipc_own_addr))
163 return;
164 if (is_slave(tipc_own_addr) && is_slave(orig))
165 return;
166 if (is_slave(orig) && !in_own_cluster(orig))
167 return;
168 if (in_own_cluster(orig)) {
169 /* Always accept link here */
170 struct sk_buff *rbuf;
171 struct tipc_media_addr *addr;
172 struct node *n_ptr = tipc_node_find(orig);
173 int link_up;
174 dbg(" in own cluster\n");
175 if (n_ptr == NULL) {
176 n_ptr = tipc_node_create(orig);
178 if (n_ptr == NULL) {
179 return;
181 spin_lock_bh(&n_ptr->lock);
182 link = n_ptr->links[b_ptr->identity];
183 if (!link) {
184 dbg("creating link\n");
185 link = tipc_link_create(b_ptr, orig, &media_addr);
186 if (!link) {
187 spin_unlock_bh(&n_ptr->lock);
188 return;
191 addr = &link->media_addr;
192 if (memcmp(addr, &media_addr, sizeof(*addr))) {
193 warn("Resetting link <%s>, peer interface address changed\n",
194 link->name);
195 memcpy(addr, &media_addr, sizeof(*addr));
196 tipc_link_reset(link);
198 link_up = tipc_link_is_up(link);
199 spin_unlock_bh(&n_ptr->lock);
200 if ((type == DSC_RESP_MSG) || link_up)
201 return;
202 rbuf = tipc_disc_init_msg(DSC_RESP_MSG, 1, orig, b_ptr);
203 if (rbuf != NULL) {
204 msg_dbg(buf_msg(rbuf),"SEND:");
205 b_ptr->media->send_msg(rbuf, &b_ptr->publ, &media_addr);
206 buf_discard(rbuf);
212 * tipc_disc_stop_link_req - stop sending periodic link setup requests
213 * @req: ptr to link request structure
216 void tipc_disc_stop_link_req(struct link_req *req)
218 if (!req)
219 return;
221 k_cancel_timer(&req->timer);
222 k_term_timer(&req->timer);
223 buf_discard(req->buf);
224 kfree(req);
228 * tipc_disc_update_link_req - update frequency of periodic link setup requests
229 * @req: ptr to link request structure
232 void tipc_disc_update_link_req(struct link_req *req)
234 if (!req)
235 return;
237 if (req->timer_intv == TIPC_LINK_REQ_SLOW) {
238 if (!req->bearer->nodes.count) {
239 req->timer_intv = TIPC_LINK_REQ_FAST;
240 k_start_timer(&req->timer, req->timer_intv);
242 } else if (req->timer_intv == TIPC_LINK_REQ_FAST) {
243 if (req->bearer->nodes.count) {
244 req->timer_intv = TIPC_LINK_REQ_SLOW;
245 k_start_timer(&req->timer, req->timer_intv);
247 } else {
248 /* leave timer "as is" if haven't yet reached a "normal" rate */
253 * disc_timeout - send a periodic link setup request
254 * @req: ptr to link request structure
256 * Called whenever a link setup request timer associated with a bearer expires.
259 static void disc_timeout(struct link_req *req)
261 spin_lock_bh(&req->bearer->publ.lock);
263 req->bearer->media->send_msg(req->buf, &req->bearer->publ, &req->dest);
265 if ((req->timer_intv == TIPC_LINK_REQ_SLOW) ||
266 (req->timer_intv == TIPC_LINK_REQ_FAST)) {
267 /* leave timer interval "as is" if already at a "normal" rate */
268 } else {
269 req->timer_intv *= 2;
270 if (req->timer_intv > TIPC_LINK_REQ_FAST)
271 req->timer_intv = TIPC_LINK_REQ_FAST;
272 if ((req->timer_intv == TIPC_LINK_REQ_FAST) &&
273 (req->bearer->nodes.count))
274 req->timer_intv = TIPC_LINK_REQ_SLOW;
276 k_start_timer(&req->timer, req->timer_intv);
278 spin_unlock_bh(&req->bearer->publ.lock);
282 * tipc_disc_init_link_req - start sending periodic link setup requests
283 * @b_ptr: ptr to bearer issuing requests
284 * @dest: destination address for request messages
285 * @dest_domain: network domain of node(s) which should respond to message
286 * @req_links: max number of desired links
288 * Returns pointer to link request structure, or NULL if unable to create.
291 struct link_req *tipc_disc_init_link_req(struct bearer *b_ptr,
292 const struct tipc_media_addr *dest,
293 u32 dest_domain,
294 u32 req_links)
296 struct link_req *req;
298 req = kmalloc(sizeof(*req), GFP_ATOMIC);
299 if (!req)
300 return NULL;
302 req->buf = tipc_disc_init_msg(DSC_REQ_MSG, req_links, dest_domain, b_ptr);
303 if (!req->buf) {
304 kfree(req);
305 return NULL;
308 memcpy(&req->dest, dest, sizeof(*dest));
309 req->bearer = b_ptr;
310 req->timer_intv = TIPC_LINK_REQ_INIT;
311 k_init_timer(&req->timer, (Handler)disc_timeout, (unsigned long)req);
312 k_start_timer(&req->timer, req->timer_intv);
313 return req;