4 * Copyright (c) 2003-2006, 2014-2015, Ericsson AB
5 * Copyright (c) 2005-2006, 2010-2011, Wind River Systems
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18 * this software without specific prior written permission.
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41 /* min delay during bearer start up */
42 #define TIPC_DISC_INIT msecs_to_jiffies(125)
43 /* max delay if bearer has no links */
44 #define TIPC_DISC_FAST msecs_to_jiffies(1000)
45 /* max delay if bearer has links */
46 #define TIPC_DISC_SLOW msecs_to_jiffies(60000)
47 /* indicates no timer in use */
48 #define TIPC_DISC_INACTIVE 0xffffffff
51 * struct tipc_discoverer - 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 * @skb: 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_discoverer {
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 to bearer issuing message
80 static void tipc_disc_init_msg(struct net *net, struct sk_buff *skb,
81 u32 mtyp, struct tipc_bearer *b)
83 struct tipc_net *tn = tipc_net(net);
84 u32 self = tipc_own_addr(net);
85 u32 dest_domain = b->domain;
89 tipc_msg_init(self, hdr, LINK_CONFIG, mtyp,
90 MAX_H_SIZE, dest_domain);
91 msg_set_non_seq(hdr, 1);
92 msg_set_node_sig(hdr, tn->random);
93 msg_set_node_capabilities(hdr, TIPC_NODE_CAPABILITIES);
94 msg_set_dest_domain(hdr, dest_domain);
95 msg_set_bc_netid(hdr, tn->net_id);
96 b->media->addr2msg(msg_media_addr(hdr), &b->addr);
99 static void tipc_disc_msg_xmit(struct net *net, u32 mtyp, u32 dst, u32 src,
100 struct tipc_media_addr *maddr,
101 struct tipc_bearer *b)
105 skb = tipc_buf_acquire(MAX_H_SIZE, GFP_ATOMIC);
108 tipc_disc_init_msg(net, skb, mtyp, b);
109 tipc_bearer_xmit_skb(net, b->identity, skb, maddr);
113 * disc_dupl_alert - issue node address duplication alert
114 * @b: pointer to bearer detecting duplication
115 * @node_addr: duplicated node address
116 * @media_addr: media address advertised by duplicated node
118 static void disc_dupl_alert(struct tipc_bearer *b, u32 node_addr,
119 struct tipc_media_addr *media_addr)
121 char node_addr_str[16];
122 char media_addr_str[64];
124 tipc_addr_string_fill(node_addr_str, node_addr);
125 tipc_media_addr_printf(media_addr_str, sizeof(media_addr_str),
127 pr_warn("Duplicate %s using %s seen on <%s>\n", node_addr_str,
128 media_addr_str, b->name);
132 * tipc_disc_rcv - handle incoming discovery message (request or response)
133 * @net: applicable net namespace
134 * @skb: buffer containing message
135 * @b: bearer that message arrived on
137 void tipc_disc_rcv(struct net *net, struct sk_buff *skb,
138 struct tipc_bearer *b)
140 struct tipc_net *tn = tipc_net(net);
141 struct tipc_msg *hdr = buf_msg(skb);
142 u16 caps = msg_node_capabilities(hdr);
143 bool legacy = tn->legacy_addr_format;
144 u32 signature = msg_node_sig(hdr);
145 u32 dst = msg_dest_domain(hdr);
146 u32 net_id = msg_bc_netid(hdr);
147 u32 self = tipc_own_addr(net);
148 struct tipc_media_addr maddr;
149 u32 src = msg_prevnode(hdr);
150 u32 mtyp = msg_type(hdr);
151 bool dupl_addr = false;
152 bool respond = false;
155 err = b->media->msg2addr(b, &maddr, msg_media_addr(hdr));
157 if (err || maddr.broadcast) {
158 pr_warn_ratelimited("Rcv corrupt discovery message\n");
161 /* Ignore discovery messages from own node */
162 if (!memcmp(&maddr, &b->addr, sizeof(maddr)))
164 if (net_id != tn->net_id)
166 if (in_own_node(net, src)) {
167 disc_dupl_alert(b, self, &maddr);
170 if (!tipc_in_scope(legacy, dst, self))
172 if (!tipc_in_scope(legacy, b->domain, src))
175 tipc_node_check_dest(net, src, b, caps, signature,
176 &maddr, &respond, &dupl_addr);
178 disc_dupl_alert(b, src, &maddr);
181 if (mtyp != DSC_REQ_MSG)
183 tipc_disc_msg_xmit(net, DSC_RESP_MSG, src, self, &maddr, b);
186 /* tipc_disc_add_dest - increment set of discovered nodes
188 void tipc_disc_add_dest(struct tipc_discoverer *d)
190 spin_lock_bh(&d->lock);
192 spin_unlock_bh(&d->lock);
195 /* tipc_disc_remove_dest - decrement set of discovered nodes
197 void tipc_disc_remove_dest(struct tipc_discoverer *d)
201 spin_lock_bh(&d->lock);
204 intv = d->timer_intv;
205 if (!num && (intv == TIPC_DISC_INACTIVE || intv > TIPC_DISC_FAST)) {
206 d->timer_intv = TIPC_DISC_INIT;
207 mod_timer(&d->timer, jiffies + d->timer_intv);
209 spin_unlock_bh(&d->lock);
212 /* tipc_disc_timeout - send a periodic link setup request
213 * Called whenever a link setup request timer associated with a bearer expires.
214 * - Keep doubling time between sent request until limit is reached;
215 * - Hold at fast polling rate if we don't have any associated nodes
216 * - Otherwise hold at slow polling rate
218 static void tipc_disc_timeout(struct timer_list *t)
220 struct tipc_discoverer *d = from_timer(d, t, timer);
221 struct tipc_media_addr maddr;
222 struct sk_buff *skb = NULL;
226 spin_lock_bh(&d->lock);
228 /* Stop searching if only desired node has been found */
229 if (tipc_node(d->domain) && d->num_nodes) {
230 d->timer_intv = TIPC_DISC_INACTIVE;
233 /* Adjust timeout interval according to discovery phase */
235 if (d->num_nodes && d->timer_intv > TIPC_DISC_SLOW)
236 d->timer_intv = TIPC_DISC_SLOW;
237 else if (!d->num_nodes && d->timer_intv > TIPC_DISC_FAST)
238 d->timer_intv = TIPC_DISC_FAST;
239 mod_timer(&d->timer, jiffies + d->timer_intv);
240 memcpy(&maddr, &d->dest, sizeof(maddr));
241 skb = skb_clone(d->skb, GFP_ATOMIC);
243 bearer_id = d->bearer_id;
245 spin_unlock_bh(&d->lock);
247 tipc_bearer_xmit_skb(net, bearer_id, skb, &maddr);
251 * tipc_disc_create - create object to send periodic link setup requests
252 * @net: the applicable net namespace
253 * @b: ptr to bearer issuing requests
254 * @dest: destination address for request messages
255 * @dest_domain: network domain to which links can be established
257 * Returns 0 if successful, otherwise -errno.
259 int tipc_disc_create(struct net *net, struct tipc_bearer *b,
260 struct tipc_media_addr *dest, struct sk_buff **skb)
262 struct tipc_discoverer *d;
264 d = kmalloc(sizeof(*d), GFP_ATOMIC);
267 d->skb = tipc_buf_acquire(MAX_H_SIZE, GFP_ATOMIC);
273 tipc_disc_init_msg(net, d->skb, DSC_REQ_MSG, b);
274 memcpy(&d->dest, dest, sizeof(*dest));
276 d->bearer_id = b->identity;
277 d->domain = b->domain;
279 d->timer_intv = TIPC_DISC_INIT;
280 spin_lock_init(&d->lock);
281 timer_setup(&d->timer, tipc_disc_timeout, 0);
282 mod_timer(&d->timer, jiffies + d->timer_intv);
284 *skb = skb_clone(d->skb, GFP_ATOMIC);
289 * tipc_disc_delete - destroy object sending periodic link setup requests
290 * @d: ptr to link duest structure
292 void tipc_disc_delete(struct tipc_discoverer *d)
294 del_timer_sync(&d->timer);
300 * tipc_disc_reset - reset object to send periodic link setup requests
301 * @net: the applicable net namespace
302 * @b: ptr to bearer issuing requests
303 * @dest_domain: network domain to which links can be established
305 void tipc_disc_reset(struct net *net, struct tipc_bearer *b)
307 struct tipc_discoverer *d = b->disc;
308 struct tipc_media_addr maddr;
311 spin_lock_bh(&d->lock);
312 tipc_disc_init_msg(net, d->skb, DSC_REQ_MSG, b);
314 d->bearer_id = b->identity;
315 d->domain = b->domain;
317 d->timer_intv = TIPC_DISC_INIT;
318 memcpy(&maddr, &d->dest, sizeof(maddr));
319 mod_timer(&d->timer, jiffies + d->timer_intv);
320 skb = skb_clone(d->skb, GFP_ATOMIC);
321 spin_unlock_bh(&d->lock);
323 tipc_bearer_xmit_skb(net, b->identity, skb, &maddr);