4 * Copyright (c) 2003-2006, 2014-2015, Ericsson AB
5 * Copyright (c) 2005-2006, 2010-2011, Wind River Systems
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41 /* min delay during bearer start up */
42 #define TIPC_LINK_REQ_INIT msecs_to_jiffies(125)
43 /* max delay if bearer has no links */
44 #define TIPC_LINK_REQ_FAST msecs_to_jiffies(1000)
45 /* max delay if bearer has links */
46 #define TIPC_LINK_REQ_SLOW msecs_to_jiffies(60000)
47 /* indicates no timer in use */
48 #define TIPC_LINK_REQ_INACTIVE 0xffffffff
51 * struct tipc_link_req - information about an ongoing link setup request
52 * @bearer_id: identity of bearer issuing requests
53 * @net: network namespace instance
54 * @dest: destination address for request messages
55 * @domain: network domain to which links can be established
56 * @num_nodes: number of nodes currently discovered (i.e. with an active link)
57 * @lock: spinlock for controlling access to requests
58 * @buf: request message to be (repeatedly) sent
59 * @timer: timer governing period between requests
60 * @timer_intv: current interval between requests (in ms)
62 struct tipc_link_req {
64 struct tipc_media_addr dest;
70 struct timer_list timer;
71 unsigned long timer_intv;
75 * tipc_disc_init_msg - initialize a link setup message
76 * @net: the applicable net namespace
77 * @type: message type (request or response)
78 * @b_ptr: ptr to bearer issuing message
80 static void tipc_disc_init_msg(struct net *net, struct sk_buff *buf, u32 type,
81 struct tipc_bearer *b_ptr)
83 struct tipc_net *tn = net_generic(net, tipc_net_id);
85 u32 dest_domain = b_ptr->domain;
88 tipc_msg_init(tn->own_addr, msg, LINK_CONFIG, type,
89 MAX_H_SIZE, dest_domain);
90 msg_set_non_seq(msg, 1);
91 msg_set_node_sig(msg, tn->random);
92 msg_set_node_capabilities(msg, 0);
93 msg_set_dest_domain(msg, dest_domain);
94 msg_set_bc_netid(msg, tn->net_id);
95 b_ptr->media->addr2msg(msg_media_addr(msg), &b_ptr->addr);
99 * disc_dupl_alert - issue node address duplication alert
100 * @b_ptr: pointer to bearer detecting duplication
101 * @node_addr: duplicated node address
102 * @media_addr: media address advertised by duplicated node
104 static void disc_dupl_alert(struct tipc_bearer *b_ptr, u32 node_addr,
105 struct tipc_media_addr *media_addr)
107 char node_addr_str[16];
108 char media_addr_str[64];
110 tipc_addr_string_fill(node_addr_str, node_addr);
111 tipc_media_addr_printf(media_addr_str, sizeof(media_addr_str),
113 pr_warn("Duplicate %s using %s seen on <%s>\n", node_addr_str,
114 media_addr_str, b_ptr->name);
118 * tipc_disc_rcv - handle incoming discovery message (request or response)
119 * @net: the applicable net namespace
120 * @buf: buffer containing message
121 * @bearer: bearer that message arrived on
123 void tipc_disc_rcv(struct net *net, struct sk_buff *skb,
124 struct tipc_bearer *bearer)
126 struct tipc_net *tn = net_generic(net, tipc_net_id);
127 struct tipc_media_addr maddr;
128 struct sk_buff *rskb;
129 struct tipc_msg *hdr = buf_msg(skb);
130 u32 ddom = msg_dest_domain(hdr);
131 u32 onode = msg_prevnode(hdr);
132 u32 net_id = msg_bc_netid(hdr);
133 u32 mtyp = msg_type(hdr);
134 u32 signature = msg_node_sig(hdr);
135 u16 caps = msg_node_capabilities(hdr);
136 bool respond = false;
137 bool dupl_addr = false;
139 bearer->media->msg2addr(bearer, &maddr, msg_media_addr(hdr));
142 /* Ensure message from node is valid and communication is permitted */
143 if (net_id != tn->net_id)
147 if (!tipc_addr_domain_valid(ddom))
149 if (!tipc_addr_node_valid(onode))
152 if (in_own_node(net, onode)) {
153 if (memcmp(&maddr, &bearer->addr, sizeof(maddr)))
154 disc_dupl_alert(bearer, tn->own_addr, &maddr);
157 if (!tipc_in_scope(ddom, tn->own_addr))
159 if (!tipc_in_scope(bearer->domain, onode))
162 tipc_node_check_dest(net, onode, bearer, caps, signature,
163 &maddr, &respond, &dupl_addr);
165 disc_dupl_alert(bearer, onode, &maddr);
167 /* Send response, if necessary */
168 if (respond && (mtyp == DSC_REQ_MSG)) {
169 rskb = tipc_buf_acquire(MAX_H_SIZE);
171 tipc_disc_init_msg(net, rskb, DSC_RESP_MSG, bearer);
172 tipc_bearer_send(net, bearer->identity, rskb, &maddr);
179 * disc_update - update frequency of periodic link setup requests
180 * @req: ptr to link request structure
182 * Reinitiates discovery process if discovery object has no associated nodes
183 * and is either not currently searching or is searching at a slow rate
185 static void disc_update(struct tipc_link_req *req)
187 if (!req->num_nodes) {
188 if ((req->timer_intv == TIPC_LINK_REQ_INACTIVE) ||
189 (req->timer_intv > TIPC_LINK_REQ_FAST)) {
190 req->timer_intv = TIPC_LINK_REQ_INIT;
191 mod_timer(&req->timer, jiffies + req->timer_intv);
197 * tipc_disc_add_dest - increment set of discovered nodes
198 * @req: ptr to link request structure
200 void tipc_disc_add_dest(struct tipc_link_req *req)
202 spin_lock_bh(&req->lock);
204 spin_unlock_bh(&req->lock);
208 * tipc_disc_remove_dest - decrement set of discovered nodes
209 * @req: ptr to link request structure
211 void tipc_disc_remove_dest(struct tipc_link_req *req)
213 spin_lock_bh(&req->lock);
216 spin_unlock_bh(&req->lock);
220 * disc_timeout - send a periodic link setup request
221 * @data: ptr to link request structure
223 * Called whenever a link setup request timer associated with a bearer expires.
225 static void disc_timeout(unsigned long data)
227 struct tipc_link_req *req = (struct tipc_link_req *)data;
230 spin_lock_bh(&req->lock);
232 /* Stop searching if only desired node has been found */
233 if (tipc_node(req->domain) && req->num_nodes) {
234 req->timer_intv = TIPC_LINK_REQ_INACTIVE;
239 * Send discovery message, then update discovery timer
241 * Keep doubling time between requests until limit is reached;
242 * hold at fast polling rate if don't have any associated nodes,
243 * otherwise hold at slow polling rate
245 tipc_bearer_send(req->net, req->bearer_id, req->buf, &req->dest);
248 req->timer_intv *= 2;
250 max_delay = TIPC_LINK_REQ_SLOW;
252 max_delay = TIPC_LINK_REQ_FAST;
253 if (req->timer_intv > max_delay)
254 req->timer_intv = max_delay;
256 mod_timer(&req->timer, jiffies + req->timer_intv);
258 spin_unlock_bh(&req->lock);
262 * tipc_disc_create - create object to send periodic link setup requests
263 * @net: the applicable net namespace
264 * @b_ptr: ptr to bearer issuing requests
265 * @dest: destination address for request messages
266 * @dest_domain: network domain to which links can be established
268 * Returns 0 if successful, otherwise -errno.
270 int tipc_disc_create(struct net *net, struct tipc_bearer *b_ptr,
271 struct tipc_media_addr *dest)
273 struct tipc_link_req *req;
275 req = kmalloc(sizeof(*req), GFP_ATOMIC);
278 req->buf = tipc_buf_acquire(MAX_H_SIZE);
284 tipc_disc_init_msg(net, req->buf, DSC_REQ_MSG, b_ptr);
285 memcpy(&req->dest, dest, sizeof(*dest));
287 req->bearer_id = b_ptr->identity;
288 req->domain = b_ptr->domain;
290 req->timer_intv = TIPC_LINK_REQ_INIT;
291 spin_lock_init(&req->lock);
292 setup_timer(&req->timer, disc_timeout, (unsigned long)req);
293 mod_timer(&req->timer, jiffies + req->timer_intv);
294 b_ptr->link_req = req;
295 tipc_bearer_send(net, req->bearer_id, req->buf, &req->dest);
300 * tipc_disc_delete - destroy object sending periodic link setup requests
301 * @req: ptr to link request structure
303 void tipc_disc_delete(struct tipc_link_req *req)
305 del_timer_sync(&req->timer);
311 * tipc_disc_reset - reset object to send periodic link setup requests
312 * @net: the applicable net namespace
313 * @b_ptr: ptr to bearer issuing requests
314 * @dest_domain: network domain to which links can be established
316 void tipc_disc_reset(struct net *net, struct tipc_bearer *b_ptr)
318 struct tipc_link_req *req = b_ptr->link_req;
320 spin_lock_bh(&req->lock);
321 tipc_disc_init_msg(net, req->buf, DSC_REQ_MSG, b_ptr);
323 req->bearer_id = b_ptr->identity;
324 req->domain = b_ptr->domain;
326 req->timer_intv = TIPC_LINK_REQ_INIT;
327 mod_timer(&req->timer, jiffies + req->timer_intv);
328 tipc_bearer_send(net, req->bearer_id, req->buf, &req->dest);
329 spin_unlock_bh(&req->lock);