1 /*
2  * net/tipc/bcast.c: TIPC broadcast code
3  *
4  * Copyright (c) 2004-2006, Ericsson AB
5  * Copyright (c) 2004, Intel Corporation.
6  * Copyright (c) 2005, 2010-2011, Wind River Systems
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the names of the copyright holders nor the names of its
18  *    contributors may be used to endorse or promote products derived from
19  *    this software without specific prior written permission.
20  *
21  * Alternatively, this software may be distributed under the terms of the
22  * GNU General Public License ("GPL") version 2 as published by the Free
23  * Software Foundation.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
26  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
29  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35  * POSSIBILITY OF SUCH DAMAGE.
36  */
37 
38 #include "core.h"
39 #include "link.h"
40 #include "port.h"
41 #include "bcast.h"
42 #include "name_distr.h"
43 
44 #define MAX_PKT_DEFAULT_MCAST 1500	/* bcast link max packet size (fixed) */
45 
46 #define BCLINK_WIN_DEFAULT 20		/* bcast link window size (default) */
47 
48 /**
49  * struct tipc_bcbearer_pair - a pair of bearers used by broadcast link
50  * @primary: pointer to primary bearer
51  * @secondary: pointer to secondary bearer
52  *
53  * Bearers must have same priority and same set of reachable destinations
54  * to be paired.
55  */
56 
57 struct tipc_bcbearer_pair {
58 	struct tipc_bearer *primary;
59 	struct tipc_bearer *secondary;
60 };
61 
62 /**
63  * struct tipc_bcbearer - bearer used by broadcast link
64  * @bearer: (non-standard) broadcast bearer structure
65  * @media: (non-standard) broadcast media structure
66  * @bpairs: array of bearer pairs
67  * @bpairs_temp: temporary array of bearer pairs used by tipc_bcbearer_sort()
68  * @remains: temporary node map used by tipc_bcbearer_send()
69  * @remains_new: temporary node map used tipc_bcbearer_send()
70  *
71  * Note: The fields labelled "temporary" are incorporated into the bearer
72  * to avoid consuming potentially limited stack space through the use of
73  * large local variables within multicast routines.  Concurrent access is
74  * prevented through use of the spinlock "bc_lock".
75  */
76 
77 struct tipc_bcbearer {
78 	struct tipc_bearer bearer;
79 	struct tipc_media media;
80 	struct tipc_bcbearer_pair bpairs[MAX_BEARERS];
81 	struct tipc_bcbearer_pair bpairs_temp[TIPC_MAX_LINK_PRI + 1];
82 	struct tipc_node_map remains;
83 	struct tipc_node_map remains_new;
84 };
85 
86 /**
87  * struct tipc_bclink - link used for broadcast messages
88  * @link: (non-standard) broadcast link structure
89  * @node: (non-standard) node structure representing b'cast link's peer node
90  * @bcast_nodes: map of broadcast-capable nodes
91  * @retransmit_to: node that most recently requested a retransmit
92  *
93  * Handles sequence numbering, fragmentation, bundling, etc.
94  */
95 
96 struct tipc_bclink {
97 	struct tipc_link link;
98 	struct tipc_node node;
99 	struct tipc_node_map bcast_nodes;
100 	struct tipc_node *retransmit_to;
101 };
102 
103 static struct tipc_bcbearer bcast_bearer;
104 static struct tipc_bclink bcast_link;
105 
106 static struct tipc_bcbearer *bcbearer = &bcast_bearer;
107 static struct tipc_bclink *bclink = &bcast_link;
108 static struct tipc_link *bcl = &bcast_link.link;
109 
110 static DEFINE_SPINLOCK(bc_lock);
111 
112 const char tipc_bclink_name[] = "broadcast-link";
113 
114 static void tipc_nmap_diff(struct tipc_node_map *nm_a,
115 			   struct tipc_node_map *nm_b,
116 			   struct tipc_node_map *nm_diff);
117 
bcbuf_acks(struct sk_buff * buf)118 static u32 bcbuf_acks(struct sk_buff *buf)
119 {
120 	return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
121 }
122 
bcbuf_set_acks(struct sk_buff * buf,u32 acks)123 static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
124 {
125 	TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
126 }
127 
bcbuf_decr_acks(struct sk_buff * buf)128 static void bcbuf_decr_acks(struct sk_buff *buf)
129 {
130 	bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
131 }
132 
tipc_bclink_add_node(u32 addr)133 void tipc_bclink_add_node(u32 addr)
134 {
135 	spin_lock_bh(&bc_lock);
136 	tipc_nmap_add(&bclink->bcast_nodes, addr);
137 	spin_unlock_bh(&bc_lock);
138 }
139 
tipc_bclink_remove_node(u32 addr)140 void tipc_bclink_remove_node(u32 addr)
141 {
142 	spin_lock_bh(&bc_lock);
143 	tipc_nmap_remove(&bclink->bcast_nodes, addr);
144 	spin_unlock_bh(&bc_lock);
145 }
146 
bclink_set_last_sent(void)147 static void bclink_set_last_sent(void)
148 {
149 	if (bcl->next_out)
150 		bcl->fsm_msg_cnt = mod(buf_seqno(bcl->next_out) - 1);
151 	else
152 		bcl->fsm_msg_cnt = mod(bcl->next_out_no - 1);
153 }
154 
tipc_bclink_get_last_sent(void)155 u32 tipc_bclink_get_last_sent(void)
156 {
157 	return bcl->fsm_msg_cnt;
158 }
159 
bclink_update_last_sent(struct tipc_node * node,u32 seqno)160 static void bclink_update_last_sent(struct tipc_node *node, u32 seqno)
161 {
162 	node->bclink.last_sent = less_eq(node->bclink.last_sent, seqno) ?
163 						seqno : node->bclink.last_sent;
164 }
165 
166 
167 /*
168  * tipc_bclink_retransmit_to - get most recent node to request retransmission
169  *
170  * Called with bc_lock locked
171  */
172 
tipc_bclink_retransmit_to(void)173 struct tipc_node *tipc_bclink_retransmit_to(void)
174 {
175 	return bclink->retransmit_to;
176 }
177 
178 /**
179  * bclink_retransmit_pkt - retransmit broadcast packets
180  * @after: sequence number of last packet to *not* retransmit
181  * @to: sequence number of last packet to retransmit
182  *
183  * Called with bc_lock locked
184  */
185 
bclink_retransmit_pkt(u32 after,u32 to)186 static void bclink_retransmit_pkt(u32 after, u32 to)
187 {
188 	struct sk_buff *buf;
189 
190 	buf = bcl->first_out;
191 	while (buf && less_eq(buf_seqno(buf), after))
192 		buf = buf->next;
193 	tipc_link_retransmit(bcl, buf, mod(to - after));
194 }
195 
196 /**
197  * tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
198  * @n_ptr: node that sent acknowledgement info
199  * @acked: broadcast sequence # that has been acknowledged
200  *
201  * Node is locked, bc_lock unlocked.
202  */
203 
tipc_bclink_acknowledge(struct tipc_node * n_ptr,u32 acked)204 void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
205 {
206 	struct sk_buff *crs;
207 	struct sk_buff *next;
208 	unsigned int released = 0;
209 
210 	spin_lock_bh(&bc_lock);
211 
212 	/* Bail out if tx queue is empty (no clean up is required) */
213 	crs = bcl->first_out;
214 	if (!crs)
215 		goto exit;
216 
217 	/* Determine which messages need to be acknowledged */
218 	if (acked == INVALID_LINK_SEQ) {
219 		/*
220 		 * Contact with specified node has been lost, so need to
221 		 * acknowledge sent messages only (if other nodes still exist)
222 		 * or both sent and unsent messages (otherwise)
223 		 */
224 		if (bclink->bcast_nodes.count)
225 			acked = bcl->fsm_msg_cnt;
226 		else
227 			acked = bcl->next_out_no;
228 	} else {
229 		/*
230 		 * Bail out if specified sequence number does not correspond
231 		 * to a message that has been sent and not yet acknowledged
232 		 */
233 		if (less(acked, buf_seqno(crs)) ||
234 		    less(bcl->fsm_msg_cnt, acked) ||
235 		    less_eq(acked, n_ptr->bclink.acked))
236 			goto exit;
237 	}
238 
239 	/* Skip over packets that node has previously acknowledged */
240 	while (crs && less_eq(buf_seqno(crs), n_ptr->bclink.acked))
241 		crs = crs->next;
242 
243 	/* Update packets that node is now acknowledging */
244 
245 	while (crs && less_eq(buf_seqno(crs), acked)) {
246 		next = crs->next;
247 
248 		if (crs != bcl->next_out)
249 			bcbuf_decr_acks(crs);
250 		else {
251 			bcbuf_set_acks(crs, 0);
252 			bcl->next_out = next;
253 			bclink_set_last_sent();
254 		}
255 
256 		if (bcbuf_acks(crs) == 0) {
257 			bcl->first_out = next;
258 			bcl->out_queue_size--;
259 			kfree_skb(crs);
260 			released = 1;
261 		}
262 		crs = next;
263 	}
264 	n_ptr->bclink.acked = acked;
265 
266 	/* Try resolving broadcast link congestion, if necessary */
267 
268 	if (unlikely(bcl->next_out)) {
269 		tipc_link_push_queue(bcl);
270 		bclink_set_last_sent();
271 	}
272 	if (unlikely(released && !list_empty(&bcl->waiting_ports)))
273 		tipc_link_wakeup_ports(bcl, 0);
274 exit:
275 	spin_unlock_bh(&bc_lock);
276 }
277 
278 /*
279  * tipc_bclink_update_link_state - update broadcast link state
280  *
281  * tipc_net_lock and node lock set
282  */
283 
tipc_bclink_update_link_state(struct tipc_node * n_ptr,u32 last_sent)284 void tipc_bclink_update_link_state(struct tipc_node *n_ptr, u32 last_sent)
285 {
286 	struct sk_buff *buf;
287 
288 	/* Ignore "stale" link state info */
289 
290 	if (less_eq(last_sent, n_ptr->bclink.last_in))
291 		return;
292 
293 	/* Update link synchronization state; quit if in sync */
294 
295 	bclink_update_last_sent(n_ptr, last_sent);
296 
297 	if (n_ptr->bclink.last_sent == n_ptr->bclink.last_in)
298 		return;
299 
300 	/* Update out-of-sync state; quit if loss is still unconfirmed */
301 
302 	if ((++n_ptr->bclink.oos_state) == 1) {
303 		if (n_ptr->bclink.deferred_size < (TIPC_MIN_LINK_WIN / 2))
304 			return;
305 		n_ptr->bclink.oos_state++;
306 	}
307 
308 	/* Don't NACK if one has been recently sent (or seen) */
309 
310 	if (n_ptr->bclink.oos_state & 0x1)
311 		return;
312 
313 	/* Send NACK */
314 
315 	buf = tipc_buf_acquire(INT_H_SIZE);
316 	if (buf) {
317 		struct tipc_msg *msg = buf_msg(buf);
318 
319 		tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG,
320 			      INT_H_SIZE, n_ptr->addr);
321 		msg_set_non_seq(msg, 1);
322 		msg_set_mc_netid(msg, tipc_net_id);
323 		msg_set_bcast_ack(msg, n_ptr->bclink.last_in);
324 		msg_set_bcgap_after(msg, n_ptr->bclink.last_in);
325 		msg_set_bcgap_to(msg, n_ptr->bclink.deferred_head
326 				 ? buf_seqno(n_ptr->bclink.deferred_head) - 1
327 				 : n_ptr->bclink.last_sent);
328 
329 		spin_lock_bh(&bc_lock);
330 		tipc_bearer_send(&bcbearer->bearer, buf, NULL);
331 		bcl->stats.sent_nacks++;
332 		spin_unlock_bh(&bc_lock);
333 		kfree_skb(buf);
334 
335 		n_ptr->bclink.oos_state++;
336 	}
337 }
338 
339 /*
340  * bclink_peek_nack - monitor retransmission requests sent by other nodes
341  *
342  * Delay any upcoming NACK by this node if another node has already
343  * requested the first message this node is going to ask for.
344  *
345  * Only tipc_net_lock set.
346  */
347 
bclink_peek_nack(struct tipc_msg * msg)348 static void bclink_peek_nack(struct tipc_msg *msg)
349 {
350 	struct tipc_node *n_ptr = tipc_node_find(msg_destnode(msg));
351 
352 	if (unlikely(!n_ptr))
353 		return;
354 
355 	tipc_node_lock(n_ptr);
356 
357 	if (n_ptr->bclink.supported &&
358 	    (n_ptr->bclink.last_in != n_ptr->bclink.last_sent) &&
359 	    (n_ptr->bclink.last_in == msg_bcgap_after(msg)))
360 		n_ptr->bclink.oos_state = 2;
361 
362 	tipc_node_unlock(n_ptr);
363 }
364 
365 /*
366  * tipc_bclink_send_msg - broadcast a packet to all nodes in cluster
367  */
368 
tipc_bclink_send_msg(struct sk_buff * buf)369 int tipc_bclink_send_msg(struct sk_buff *buf)
370 {
371 	int res;
372 
373 	spin_lock_bh(&bc_lock);
374 
375 	if (!bclink->bcast_nodes.count) {
376 		res = msg_data_sz(buf_msg(buf));
377 		kfree_skb(buf);
378 		goto exit;
379 	}
380 
381 	res = tipc_link_send_buf(bcl, buf);
382 	if (likely(res >= 0)) {
383 		bclink_set_last_sent();
384 		bcl->stats.queue_sz_counts++;
385 		bcl->stats.accu_queue_sz += bcl->out_queue_size;
386 	}
387 exit:
388 	spin_unlock_bh(&bc_lock);
389 	return res;
390 }
391 
392 /*
393  * bclink_accept_pkt - accept an incoming, in-sequence broadcast packet
394  *
395  * Called with both sending node's lock and bc_lock taken.
396  */
397 
bclink_accept_pkt(struct tipc_node * node,u32 seqno)398 static void bclink_accept_pkt(struct tipc_node *node, u32 seqno)
399 {
400 	bclink_update_last_sent(node, seqno);
401 	node->bclink.last_in = seqno;
402 	node->bclink.oos_state = 0;
403 	bcl->stats.recv_info++;
404 
405 	/*
406 	 * Unicast an ACK periodically, ensuring that
407 	 * all nodes in the cluster don't ACK at the same time
408 	 */
409 
410 	if (((seqno - tipc_own_addr) % TIPC_MIN_LINK_WIN) == 0) {
411 		tipc_link_send_proto_msg(
412 			node->active_links[node->addr & 1],
413 			STATE_MSG, 0, 0, 0, 0, 0);
414 		bcl->stats.sent_acks++;
415 	}
416 }
417 
418 /*
419  * tipc_bclink_recv_pkt - receive a broadcast packet, and deliver upwards
420  *
421  * tipc_net_lock is read_locked, no other locks set
422  */
423 
tipc_bclink_recv_pkt(struct sk_buff * buf)424 void tipc_bclink_recv_pkt(struct sk_buff *buf)
425 {
426 	struct tipc_msg *msg = buf_msg(buf);
427 	struct tipc_node *node;
428 	u32 next_in;
429 	u32 seqno;
430 	int deferred;
431 
432 	/* Screen out unwanted broadcast messages */
433 
434 	if (msg_mc_netid(msg) != tipc_net_id)
435 		goto exit;
436 
437 	node = tipc_node_find(msg_prevnode(msg));
438 	if (unlikely(!node))
439 		goto exit;
440 
441 	tipc_node_lock(node);
442 	if (unlikely(!node->bclink.supported))
443 		goto unlock;
444 
445 	/* Handle broadcast protocol message */
446 
447 	if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) {
448 		if (msg_type(msg) != STATE_MSG)
449 			goto unlock;
450 		if (msg_destnode(msg) == tipc_own_addr) {
451 			tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
452 			tipc_node_unlock(node);
453 			spin_lock_bh(&bc_lock);
454 			bcl->stats.recv_nacks++;
455 			bclink->retransmit_to = node;
456 			bclink_retransmit_pkt(msg_bcgap_after(msg),
457 					      msg_bcgap_to(msg));
458 			spin_unlock_bh(&bc_lock);
459 		} else {
460 			tipc_node_unlock(node);
461 			bclink_peek_nack(msg);
462 		}
463 		goto exit;
464 	}
465 
466 	/* Handle in-sequence broadcast message */
467 
468 	seqno = msg_seqno(msg);
469 	next_in = mod(node->bclink.last_in + 1);
470 
471 	if (likely(seqno == next_in)) {
472 receive:
473 		/* Deliver message to destination */
474 
475 		if (likely(msg_isdata(msg))) {
476 			spin_lock_bh(&bc_lock);
477 			bclink_accept_pkt(node, seqno);
478 			spin_unlock_bh(&bc_lock);
479 			tipc_node_unlock(node);
480 			if (likely(msg_mcast(msg)))
481 				tipc_port_recv_mcast(buf, NULL);
482 			else
483 				kfree_skb(buf);
484 		} else if (msg_user(msg) == MSG_BUNDLER) {
485 			spin_lock_bh(&bc_lock);
486 			bclink_accept_pkt(node, seqno);
487 			bcl->stats.recv_bundles++;
488 			bcl->stats.recv_bundled += msg_msgcnt(msg);
489 			spin_unlock_bh(&bc_lock);
490 			tipc_node_unlock(node);
491 			tipc_link_recv_bundle(buf);
492 		} else if (msg_user(msg) == MSG_FRAGMENTER) {
493 			int ret = tipc_link_recv_fragment(&node->bclink.defragm,
494 						      &buf, &msg);
495 			if (ret < 0)
496 				goto unlock;
497 			spin_lock_bh(&bc_lock);
498 			bclink_accept_pkt(node, seqno);
499 			bcl->stats.recv_fragments++;
500 			if (ret > 0)
501 				bcl->stats.recv_fragmented++;
502 			spin_unlock_bh(&bc_lock);
503 			tipc_node_unlock(node);
504 			tipc_net_route_msg(buf);
505 		} else if (msg_user(msg) == NAME_DISTRIBUTOR) {
506 			spin_lock_bh(&bc_lock);
507 			bclink_accept_pkt(node, seqno);
508 			spin_unlock_bh(&bc_lock);
509 			tipc_node_unlock(node);
510 			tipc_named_recv(buf);
511 		} else {
512 			spin_lock_bh(&bc_lock);
513 			bclink_accept_pkt(node, seqno);
514 			spin_unlock_bh(&bc_lock);
515 			tipc_node_unlock(node);
516 			kfree_skb(buf);
517 		}
518 		buf = NULL;
519 
520 		/* Determine new synchronization state */
521 
522 		tipc_node_lock(node);
523 		if (unlikely(!tipc_node_is_up(node)))
524 			goto unlock;
525 
526 		if (node->bclink.last_in == node->bclink.last_sent)
527 			goto unlock;
528 
529 		if (!node->bclink.deferred_head) {
530 			node->bclink.oos_state = 1;
531 			goto unlock;
532 		}
533 
534 		msg = buf_msg(node->bclink.deferred_head);
535 		seqno = msg_seqno(msg);
536 		next_in = mod(next_in + 1);
537 		if (seqno != next_in)
538 			goto unlock;
539 
540 		/* Take in-sequence message from deferred queue & deliver it */
541 
542 		buf = node->bclink.deferred_head;
543 		node->bclink.deferred_head = buf->next;
544 		node->bclink.deferred_size--;
545 		goto receive;
546 	}
547 
548 	/* Handle out-of-sequence broadcast message */
549 
550 	if (less(next_in, seqno)) {
551 		deferred = tipc_link_defer_pkt(&node->bclink.deferred_head,
552 					       &node->bclink.deferred_tail,
553 					       buf);
554 		node->bclink.deferred_size += deferred;
555 		bclink_update_last_sent(node, seqno);
556 		buf = NULL;
557 	} else
558 		deferred = 0;
559 
560 	spin_lock_bh(&bc_lock);
561 
562 	if (deferred)
563 		bcl->stats.deferred_recv++;
564 	else
565 		bcl->stats.duplicates++;
566 
567 	spin_unlock_bh(&bc_lock);
568 
569 unlock:
570 	tipc_node_unlock(node);
571 exit:
572 	kfree_skb(buf);
573 }
574 
tipc_bclink_acks_missing(struct tipc_node * n_ptr)575 u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
576 {
577 	return (n_ptr->bclink.supported &&
578 		(tipc_bclink_get_last_sent() != n_ptr->bclink.acked));
579 }
580 
581 
582 /**
583  * tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
584  *
585  * Send packet over as many bearers as necessary to reach all nodes
586  * that have joined the broadcast link.
587  *
588  * Returns 0 (packet sent successfully) under all circumstances,
589  * since the broadcast link's pseudo-bearer never blocks
590  */
591 
tipc_bcbearer_send(struct sk_buff * buf,struct tipc_bearer * unused1,struct tipc_media_addr * unused2)592 static int tipc_bcbearer_send(struct sk_buff *buf,
593 			      struct tipc_bearer *unused1,
594 			      struct tipc_media_addr *unused2)
595 {
596 	int bp_index;
597 
598 	/*
599 	 * Prepare broadcast link message for reliable transmission,
600 	 * if first time trying to send it;
601 	 * preparation is skipped for broadcast link protocol messages
602 	 * since they are sent in an unreliable manner and don't need it
603 	 */
604 
605 	if (likely(!msg_non_seq(buf_msg(buf)))) {
606 		struct tipc_msg *msg;
607 
608 		bcbuf_set_acks(buf, bclink->bcast_nodes.count);
609 		msg = buf_msg(buf);
610 		msg_set_non_seq(msg, 1);
611 		msg_set_mc_netid(msg, tipc_net_id);
612 		bcl->stats.sent_info++;
613 
614 		if (WARN_ON(!bclink->bcast_nodes.count)) {
615 			dump_stack();
616 			return 0;
617 		}
618 	}
619 
620 	/* Send buffer over bearers until all targets reached */
621 
622 	bcbearer->remains = bclink->bcast_nodes;
623 
624 	for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
625 		struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
626 		struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
627 
628 		if (!p)
629 			break;	/* no more bearers to try */
630 
631 		tipc_nmap_diff(&bcbearer->remains, &p->nodes, &bcbearer->remains_new);
632 		if (bcbearer->remains_new.count == bcbearer->remains.count)
633 			continue;	/* bearer pair doesn't add anything */
634 
635 		if (p->blocked ||
636 		    p->media->send_msg(buf, p, &p->media->bcast_addr)) {
637 			/* unable to send on primary bearer */
638 			if (!s || s->blocked ||
639 			    s->media->send_msg(buf, s,
640 					       &s->media->bcast_addr)) {
641 				/* unable to send on either bearer */
642 				continue;
643 			}
644 		}
645 
646 		if (s) {
647 			bcbearer->bpairs[bp_index].primary = s;
648 			bcbearer->bpairs[bp_index].secondary = p;
649 		}
650 
651 		if (bcbearer->remains_new.count == 0)
652 			break;	/* all targets reached */
653 
654 		bcbearer->remains = bcbearer->remains_new;
655 	}
656 
657 	return 0;
658 }
659 
660 /**
661  * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
662  */
663 
tipc_bcbearer_sort(void)664 void tipc_bcbearer_sort(void)
665 {
666 	struct tipc_bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
667 	struct tipc_bcbearer_pair *bp_curr;
668 	int b_index;
669 	int pri;
670 
671 	spin_lock_bh(&bc_lock);
672 
673 	/* Group bearers by priority (can assume max of two per priority) */
674 
675 	memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
676 
677 	for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
678 		struct tipc_bearer *b = &tipc_bearers[b_index];
679 
680 		if (!b->active || !b->nodes.count)
681 			continue;
682 
683 		if (!bp_temp[b->priority].primary)
684 			bp_temp[b->priority].primary = b;
685 		else
686 			bp_temp[b->priority].secondary = b;
687 	}
688 
689 	/* Create array of bearer pairs for broadcasting */
690 
691 	bp_curr = bcbearer->bpairs;
692 	memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
693 
694 	for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
695 
696 		if (!bp_temp[pri].primary)
697 			continue;
698 
699 		bp_curr->primary = bp_temp[pri].primary;
700 
701 		if (bp_temp[pri].secondary) {
702 			if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
703 					    &bp_temp[pri].secondary->nodes)) {
704 				bp_curr->secondary = bp_temp[pri].secondary;
705 			} else {
706 				bp_curr++;
707 				bp_curr->primary = bp_temp[pri].secondary;
708 			}
709 		}
710 
711 		bp_curr++;
712 	}
713 
714 	spin_unlock_bh(&bc_lock);
715 }
716 
717 
tipc_bclink_stats(char * buf,const u32 buf_size)718 int tipc_bclink_stats(char *buf, const u32 buf_size)
719 {
720 	struct print_buf pb;
721 
722 	if (!bcl)
723 		return 0;
724 
725 	tipc_printbuf_init(&pb, buf, buf_size);
726 
727 	spin_lock_bh(&bc_lock);
728 
729 	tipc_printf(&pb, "Link <%s>\n"
730 			 "  Window:%u packets\n",
731 		    bcl->name, bcl->queue_limit[0]);
732 	tipc_printf(&pb, "  RX packets:%u fragments:%u/%u bundles:%u/%u\n",
733 		    bcl->stats.recv_info,
734 		    bcl->stats.recv_fragments,
735 		    bcl->stats.recv_fragmented,
736 		    bcl->stats.recv_bundles,
737 		    bcl->stats.recv_bundled);
738 	tipc_printf(&pb, "  TX packets:%u fragments:%u/%u bundles:%u/%u\n",
739 		    bcl->stats.sent_info,
740 		    bcl->stats.sent_fragments,
741 		    bcl->stats.sent_fragmented,
742 		    bcl->stats.sent_bundles,
743 		    bcl->stats.sent_bundled);
744 	tipc_printf(&pb, "  RX naks:%u defs:%u dups:%u\n",
745 		    bcl->stats.recv_nacks,
746 		    bcl->stats.deferred_recv,
747 		    bcl->stats.duplicates);
748 	tipc_printf(&pb, "  TX naks:%u acks:%u dups:%u\n",
749 		    bcl->stats.sent_nacks,
750 		    bcl->stats.sent_acks,
751 		    bcl->stats.retransmitted);
752 	tipc_printf(&pb, "  Congestion bearer:%u link:%u  Send queue max:%u avg:%u\n",
753 		    bcl->stats.bearer_congs,
754 		    bcl->stats.link_congs,
755 		    bcl->stats.max_queue_sz,
756 		    bcl->stats.queue_sz_counts
757 		    ? (bcl->stats.accu_queue_sz / bcl->stats.queue_sz_counts)
758 		    : 0);
759 
760 	spin_unlock_bh(&bc_lock);
761 	return tipc_printbuf_validate(&pb);
762 }
763 
tipc_bclink_reset_stats(void)764 int tipc_bclink_reset_stats(void)
765 {
766 	if (!bcl)
767 		return -ENOPROTOOPT;
768 
769 	spin_lock_bh(&bc_lock);
770 	memset(&bcl->stats, 0, sizeof(bcl->stats));
771 	spin_unlock_bh(&bc_lock);
772 	return 0;
773 }
774 
tipc_bclink_set_queue_limits(u32 limit)775 int tipc_bclink_set_queue_limits(u32 limit)
776 {
777 	if (!bcl)
778 		return -ENOPROTOOPT;
779 	if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
780 		return -EINVAL;
781 
782 	spin_lock_bh(&bc_lock);
783 	tipc_link_set_queue_limits(bcl, limit);
784 	spin_unlock_bh(&bc_lock);
785 	return 0;
786 }
787 
tipc_bclink_init(void)788 void tipc_bclink_init(void)
789 {
790 	INIT_LIST_HEAD(&bcbearer->bearer.cong_links);
791 	bcbearer->bearer.media = &bcbearer->media;
792 	bcbearer->media.send_msg = tipc_bcbearer_send;
793 	sprintf(bcbearer->media.name, "tipc-broadcast");
794 
795 	INIT_LIST_HEAD(&bcl->waiting_ports);
796 	bcl->next_out_no = 1;
797 	spin_lock_init(&bclink->node.lock);
798 	bcl->owner = &bclink->node;
799 	bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
800 	tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
801 	bcl->b_ptr = &bcbearer->bearer;
802 	bcl->state = WORKING_WORKING;
803 	strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
804 }
805 
tipc_bclink_stop(void)806 void tipc_bclink_stop(void)
807 {
808 	spin_lock_bh(&bc_lock);
809 	tipc_link_stop(bcl);
810 	spin_unlock_bh(&bc_lock);
811 
812 	memset(bclink, 0, sizeof(*bclink));
813 	memset(bcbearer, 0, sizeof(*bcbearer));
814 }
815 
816 
817 /**
818  * tipc_nmap_add - add a node to a node map
819  */
820 
tipc_nmap_add(struct tipc_node_map * nm_ptr,u32 node)821 void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node)
822 {
823 	int n = tipc_node(node);
824 	int w = n / WSIZE;
825 	u32 mask = (1 << (n % WSIZE));
826 
827 	if ((nm_ptr->map[w] & mask) == 0) {
828 		nm_ptr->count++;
829 		nm_ptr->map[w] |= mask;
830 	}
831 }
832 
833 /**
834  * tipc_nmap_remove - remove a node from a node map
835  */
836 
tipc_nmap_remove(struct tipc_node_map * nm_ptr,u32 node)837 void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node)
838 {
839 	int n = tipc_node(node);
840 	int w = n / WSIZE;
841 	u32 mask = (1 << (n % WSIZE));
842 
843 	if ((nm_ptr->map[w] & mask) != 0) {
844 		nm_ptr->map[w] &= ~mask;
845 		nm_ptr->count--;
846 	}
847 }
848 
849 /**
850  * tipc_nmap_diff - find differences between node maps
851  * @nm_a: input node map A
852  * @nm_b: input node map B
853  * @nm_diff: output node map A-B (i.e. nodes of A that are not in B)
854  */
855 
tipc_nmap_diff(struct tipc_node_map * nm_a,struct tipc_node_map * nm_b,struct tipc_node_map * nm_diff)856 static void tipc_nmap_diff(struct tipc_node_map *nm_a,
857 			   struct tipc_node_map *nm_b,
858 			   struct tipc_node_map *nm_diff)
859 {
860 	int stop = ARRAY_SIZE(nm_a->map);
861 	int w;
862 	int b;
863 	u32 map;
864 
865 	memset(nm_diff, 0, sizeof(*nm_diff));
866 	for (w = 0; w < stop; w++) {
867 		map = nm_a->map[w] ^ (nm_a->map[w] & nm_b->map[w]);
868 		nm_diff->map[w] = map;
869 		if (map != 0) {
870 			for (b = 0 ; b < WSIZE; b++) {
871 				if (map & (1 << b))
872 					nm_diff->count++;
873 			}
874 		}
875 	}
876 }
877 
878 /**
879  * tipc_port_list_add - add a port to a port list, ensuring no duplicates
880  */
881 
tipc_port_list_add(struct tipc_port_list * pl_ptr,u32 port)882 void tipc_port_list_add(struct tipc_port_list *pl_ptr, u32 port)
883 {
884 	struct tipc_port_list *item = pl_ptr;
885 	int i;
886 	int item_sz = PLSIZE;
887 	int cnt = pl_ptr->count;
888 
889 	for (; ; cnt -= item_sz, item = item->next) {
890 		if (cnt < PLSIZE)
891 			item_sz = cnt;
892 		for (i = 0; i < item_sz; i++)
893 			if (item->ports[i] == port)
894 				return;
895 		if (i < PLSIZE) {
896 			item->ports[i] = port;
897 			pl_ptr->count++;
898 			return;
899 		}
900 		if (!item->next) {
901 			item->next = kmalloc(sizeof(*item), GFP_ATOMIC);
902 			if (!item->next) {
903 				warn("Incomplete multicast delivery, no memory\n");
904 				return;
905 			}
906 			item->next->next = NULL;
907 		}
908 	}
909 }
910 
911 /**
912  * tipc_port_list_free - free dynamically created entries in port_list chain
913  *
914  */
915 
tipc_port_list_free(struct tipc_port_list * pl_ptr)916 void tipc_port_list_free(struct tipc_port_list *pl_ptr)
917 {
918 	struct tipc_port_list *item;
919 	struct tipc_port_list *next;
920 
921 	for (item = pl_ptr->next; item; item = next) {
922 		next = item->next;
923 		kfree(item);
924 	}
925 }
926 
927