1/*
2 * net/tipc/bcast.c: TIPC broadcast code
3 *
4 * Copyright (c) 2004-2006, 2014-2015, 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 "socket.h"
39#include "msg.h"
40#include "bcast.h"
41#include "name_distr.h"
42#include "core.h"
43
44#define	MAX_PKT_DEFAULT_MCAST	1500	/* bcast link max packet size (fixed) */
45#define	BCLINK_WIN_DEFAULT	20	/* bcast link window size (default) */
46
47const char tipc_bclink_name[] = "broadcast-link";
48
49static void tipc_nmap_diff(struct tipc_node_map *nm_a,
50			   struct tipc_node_map *nm_b,
51			   struct tipc_node_map *nm_diff);
52static void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node);
53static void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node);
54
55static void tipc_bclink_lock(struct net *net)
56{
57	struct tipc_net *tn = net_generic(net, tipc_net_id);
58
59	spin_lock_bh(&tn->bclink->lock);
60}
61
62static void tipc_bclink_unlock(struct net *net)
63{
64	struct tipc_net *tn = net_generic(net, tipc_net_id);
65
66	spin_unlock_bh(&tn->bclink->lock);
67}
68
69void tipc_bclink_input(struct net *net)
70{
71	struct tipc_net *tn = net_generic(net, tipc_net_id);
72
73	tipc_sk_mcast_rcv(net, &tn->bclink->arrvq, &tn->bclink->inputq);
74}
75
76uint  tipc_bclink_get_mtu(void)
77{
78	return MAX_PKT_DEFAULT_MCAST;
79}
80
81static u32 bcbuf_acks(struct sk_buff *buf)
82{
83	return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
84}
85
86static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
87{
88	TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
89}
90
91static void bcbuf_decr_acks(struct sk_buff *buf)
92{
93	bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
94}
95
96void tipc_bclink_add_node(struct net *net, u32 addr)
97{
98	struct tipc_net *tn = net_generic(net, tipc_net_id);
99
100	tipc_bclink_lock(net);
101	tipc_nmap_add(&tn->bclink->bcast_nodes, addr);
102	tipc_bclink_unlock(net);
103}
104
105void tipc_bclink_remove_node(struct net *net, u32 addr)
106{
107	struct tipc_net *tn = net_generic(net, tipc_net_id);
108
109	tipc_bclink_lock(net);
110	tipc_nmap_remove(&tn->bclink->bcast_nodes, addr);
111	tipc_bclink_unlock(net);
112}
113
114static void bclink_set_last_sent(struct net *net)
115{
116	struct tipc_net *tn = net_generic(net, tipc_net_id);
117	struct tipc_link *bcl = tn->bcl;
118	struct sk_buff *skb = skb_peek(&bcl->backlogq);
119
120	if (skb)
121		bcl->fsm_msg_cnt = mod(buf_seqno(skb) - 1);
122	else
123		bcl->fsm_msg_cnt = mod(bcl->next_out_no - 1);
124}
125
126u32 tipc_bclink_get_last_sent(struct net *net)
127{
128	struct tipc_net *tn = net_generic(net, tipc_net_id);
129
130	return tn->bcl->fsm_msg_cnt;
131}
132
133static void bclink_update_last_sent(struct tipc_node *node, u32 seqno)
134{
135	node->bclink.last_sent = less_eq(node->bclink.last_sent, seqno) ?
136						seqno : node->bclink.last_sent;
137}
138
139/**
140 * tipc_bclink_retransmit_to - get most recent node to request retransmission
141 *
142 * Called with bclink_lock locked
143 */
144struct tipc_node *tipc_bclink_retransmit_to(struct net *net)
145{
146	struct tipc_net *tn = net_generic(net, tipc_net_id);
147
148	return tn->bclink->retransmit_to;
149}
150
151/**
152 * bclink_retransmit_pkt - retransmit broadcast packets
153 * @after: sequence number of last packet to *not* retransmit
154 * @to: sequence number of last packet to retransmit
155 *
156 * Called with bclink_lock locked
157 */
158static void bclink_retransmit_pkt(struct tipc_net *tn, u32 after, u32 to)
159{
160	struct sk_buff *skb;
161	struct tipc_link *bcl = tn->bcl;
162
163	skb_queue_walk(&bcl->transmq, skb) {
164		if (more(buf_seqno(skb), after)) {
165			tipc_link_retransmit(bcl, skb, mod(to - after));
166			break;
167		}
168	}
169}
170
171/**
172 * tipc_bclink_wakeup_users - wake up pending users
173 *
174 * Called with no locks taken
175 */
176void tipc_bclink_wakeup_users(struct net *net)
177{
178	struct tipc_net *tn = net_generic(net, tipc_net_id);
179
180	tipc_sk_rcv(net, &tn->bclink->link.wakeupq);
181}
182
183/**
184 * tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
185 * @n_ptr: node that sent acknowledgement info
186 * @acked: broadcast sequence # that has been acknowledged
187 *
188 * Node is locked, bclink_lock unlocked.
189 */
190void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
191{
192	struct sk_buff *skb, *tmp;
193	unsigned int released = 0;
194	struct net *net = n_ptr->net;
195	struct tipc_net *tn = net_generic(net, tipc_net_id);
196
197	if (unlikely(!n_ptr->bclink.recv_permitted))
198		return;
199
200	tipc_bclink_lock(net);
201
202	/* Bail out if tx queue is empty (no clean up is required) */
203	skb = skb_peek(&tn->bcl->transmq);
204	if (!skb)
205		goto exit;
206
207	/* Determine which messages need to be acknowledged */
208	if (acked == INVALID_LINK_SEQ) {
209		/*
210		 * Contact with specified node has been lost, so need to
211		 * acknowledge sent messages only (if other nodes still exist)
212		 * or both sent and unsent messages (otherwise)
213		 */
214		if (tn->bclink->bcast_nodes.count)
215			acked = tn->bcl->fsm_msg_cnt;
216		else
217			acked = tn->bcl->next_out_no;
218	} else {
219		/*
220		 * Bail out if specified sequence number does not correspond
221		 * to a message that has been sent and not yet acknowledged
222		 */
223		if (less(acked, buf_seqno(skb)) ||
224		    less(tn->bcl->fsm_msg_cnt, acked) ||
225		    less_eq(acked, n_ptr->bclink.acked))
226			goto exit;
227	}
228
229	/* Skip over packets that node has previously acknowledged */
230	skb_queue_walk(&tn->bcl->transmq, skb) {
231		if (more(buf_seqno(skb), n_ptr->bclink.acked))
232			break;
233	}
234
235	/* Update packets that node is now acknowledging */
236	skb_queue_walk_from_safe(&tn->bcl->transmq, skb, tmp) {
237		if (more(buf_seqno(skb), acked))
238			break;
239		bcbuf_decr_acks(skb);
240		bclink_set_last_sent(net);
241		if (bcbuf_acks(skb) == 0) {
242			__skb_unlink(skb, &tn->bcl->transmq);
243			kfree_skb(skb);
244			released = 1;
245		}
246	}
247	n_ptr->bclink.acked = acked;
248
249	/* Try resolving broadcast link congestion, if necessary */
250	if (unlikely(skb_peek(&tn->bcl->backlogq))) {
251		tipc_link_push_packets(tn->bcl);
252		bclink_set_last_sent(net);
253	}
254	if (unlikely(released && !skb_queue_empty(&tn->bcl->wakeupq)))
255		n_ptr->action_flags |= TIPC_WAKEUP_BCAST_USERS;
256exit:
257	tipc_bclink_unlock(net);
258}
259
260/**
261 * tipc_bclink_update_link_state - update broadcast link state
262 *
263 * RCU and node lock set
264 */
265void tipc_bclink_update_link_state(struct tipc_node *n_ptr,
266				   u32 last_sent)
267{
268	struct sk_buff *buf;
269	struct net *net = n_ptr->net;
270	struct tipc_net *tn = net_generic(net, tipc_net_id);
271
272	/* Ignore "stale" link state info */
273	if (less_eq(last_sent, n_ptr->bclink.last_in))
274		return;
275
276	/* Update link synchronization state; quit if in sync */
277	bclink_update_last_sent(n_ptr, last_sent);
278
279	if (n_ptr->bclink.last_sent == n_ptr->bclink.last_in)
280		return;
281
282	/* Update out-of-sync state; quit if loss is still unconfirmed */
283	if ((++n_ptr->bclink.oos_state) == 1) {
284		if (n_ptr->bclink.deferred_size < (TIPC_MIN_LINK_WIN / 2))
285			return;
286		n_ptr->bclink.oos_state++;
287	}
288
289	/* Don't NACK if one has been recently sent (or seen) */
290	if (n_ptr->bclink.oos_state & 0x1)
291		return;
292
293	/* Send NACK */
294	buf = tipc_buf_acquire(INT_H_SIZE);
295	if (buf) {
296		struct tipc_msg *msg = buf_msg(buf);
297		struct sk_buff *skb = skb_peek(&n_ptr->bclink.deferdq);
298		u32 to = skb ? buf_seqno(skb) - 1 : n_ptr->bclink.last_sent;
299
300		tipc_msg_init(tn->own_addr, msg, BCAST_PROTOCOL, STATE_MSG,
301			      INT_H_SIZE, n_ptr->addr);
302		msg_set_non_seq(msg, 1);
303		msg_set_mc_netid(msg, tn->net_id);
304		msg_set_bcast_ack(msg, n_ptr->bclink.last_in);
305		msg_set_bcgap_after(msg, n_ptr->bclink.last_in);
306		msg_set_bcgap_to(msg, to);
307
308		tipc_bclink_lock(net);
309		tipc_bearer_send(net, MAX_BEARERS, buf, NULL);
310		tn->bcl->stats.sent_nacks++;
311		tipc_bclink_unlock(net);
312		kfree_skb(buf);
313
314		n_ptr->bclink.oos_state++;
315	}
316}
317
318/**
319 * bclink_peek_nack - monitor retransmission requests sent by other nodes
320 *
321 * Delay any upcoming NACK by this node if another node has already
322 * requested the first message this node is going to ask for.
323 */
324static void bclink_peek_nack(struct net *net, struct tipc_msg *msg)
325{
326	struct tipc_node *n_ptr = tipc_node_find(net, msg_destnode(msg));
327
328	if (unlikely(!n_ptr))
329		return;
330
331	tipc_node_lock(n_ptr);
332	if (n_ptr->bclink.recv_permitted &&
333	    (n_ptr->bclink.last_in != n_ptr->bclink.last_sent) &&
334	    (n_ptr->bclink.last_in == msg_bcgap_after(msg)))
335		n_ptr->bclink.oos_state = 2;
336	tipc_node_unlock(n_ptr);
337	tipc_node_put(n_ptr);
338}
339
340/* tipc_bclink_xmit - deliver buffer chain to all nodes in cluster
341 *                    and to identified node local sockets
342 * @net: the applicable net namespace
343 * @list: chain of buffers containing message
344 * Consumes the buffer chain, except when returning -ELINKCONG
345 * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
346 */
347int tipc_bclink_xmit(struct net *net, struct sk_buff_head *list)
348{
349	struct tipc_net *tn = net_generic(net, tipc_net_id);
350	struct tipc_link *bcl = tn->bcl;
351	struct tipc_bclink *bclink = tn->bclink;
352	int rc = 0;
353	int bc = 0;
354	struct sk_buff *skb;
355	struct sk_buff_head arrvq;
356	struct sk_buff_head inputq;
357
358	/* Prepare clone of message for local node */
359	skb = tipc_msg_reassemble(list);
360	if (unlikely(!skb)) {
361		__skb_queue_purge(list);
362		return -EHOSTUNREACH;
363	}
364	/* Broadcast to all nodes */
365	if (likely(bclink)) {
366		tipc_bclink_lock(net);
367		if (likely(bclink->bcast_nodes.count)) {
368			rc = __tipc_link_xmit(net, bcl, list);
369			if (likely(!rc)) {
370				u32 len = skb_queue_len(&bcl->transmq);
371
372				bclink_set_last_sent(net);
373				bcl->stats.queue_sz_counts++;
374				bcl->stats.accu_queue_sz += len;
375			}
376			bc = 1;
377		}
378		tipc_bclink_unlock(net);
379	}
380
381	if (unlikely(!bc))
382		__skb_queue_purge(list);
383
384	if (unlikely(rc)) {
385		kfree_skb(skb);
386		return rc;
387	}
388	/* Deliver message clone */
389	__skb_queue_head_init(&arrvq);
390	skb_queue_head_init(&inputq);
391	__skb_queue_tail(&arrvq, skb);
392	tipc_sk_mcast_rcv(net, &arrvq, &inputq);
393	return rc;
394}
395
396/**
397 * bclink_accept_pkt - accept an incoming, in-sequence broadcast packet
398 *
399 * Called with both sending node's lock and bclink_lock taken.
400 */
401static void bclink_accept_pkt(struct tipc_node *node, u32 seqno)
402{
403	struct tipc_net *tn = net_generic(node->net, tipc_net_id);
404
405	bclink_update_last_sent(node, seqno);
406	node->bclink.last_in = seqno;
407	node->bclink.oos_state = 0;
408	tn->bcl->stats.recv_info++;
409
410	/*
411	 * Unicast an ACK periodically, ensuring that
412	 * all nodes in the cluster don't ACK at the same time
413	 */
414	if (((seqno - tn->own_addr) % TIPC_MIN_LINK_WIN) == 0) {
415		tipc_link_proto_xmit(node->active_links[node->addr & 1],
416				     STATE_MSG, 0, 0, 0, 0);
417		tn->bcl->stats.sent_acks++;
418	}
419}
420
421/**
422 * tipc_bclink_rcv - receive a broadcast packet, and deliver upwards
423 *
424 * RCU is locked, no other locks set
425 */
426void tipc_bclink_rcv(struct net *net, struct sk_buff *buf)
427{
428	struct tipc_net *tn = net_generic(net, tipc_net_id);
429	struct tipc_link *bcl = tn->bcl;
430	struct tipc_msg *msg = buf_msg(buf);
431	struct tipc_node *node;
432	u32 next_in;
433	u32 seqno;
434	int deferred = 0;
435	int pos = 0;
436	struct sk_buff *iskb;
437	struct sk_buff_head *arrvq, *inputq;
438
439	/* Screen out unwanted broadcast messages */
440	if (msg_mc_netid(msg) != tn->net_id)
441		goto exit;
442
443	node = tipc_node_find(net, msg_prevnode(msg));
444	if (unlikely(!node))
445		goto exit;
446
447	tipc_node_lock(node);
448	if (unlikely(!node->bclink.recv_permitted))
449		goto unlock;
450
451	/* Handle broadcast protocol message */
452	if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) {
453		if (msg_type(msg) != STATE_MSG)
454			goto unlock;
455		if (msg_destnode(msg) == tn->own_addr) {
456			tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
457			tipc_bclink_lock(net);
458			bcl->stats.recv_nacks++;
459			tn->bclink->retransmit_to = node;
460			bclink_retransmit_pkt(tn, msg_bcgap_after(msg),
461					      msg_bcgap_to(msg));
462			tipc_bclink_unlock(net);
463			tipc_node_unlock(node);
464		} else {
465			tipc_node_unlock(node);
466			bclink_peek_nack(net, msg);
467		}
468		tipc_node_put(node);
469		goto exit;
470	}
471
472	/* Handle in-sequence broadcast message */
473	seqno = msg_seqno(msg);
474	next_in = mod(node->bclink.last_in + 1);
475	arrvq = &tn->bclink->arrvq;
476	inputq = &tn->bclink->inputq;
477
478	if (likely(seqno == next_in)) {
479receive:
480		/* Deliver message to destination */
481		if (likely(msg_isdata(msg))) {
482			tipc_bclink_lock(net);
483			bclink_accept_pkt(node, seqno);
484			spin_lock_bh(&inputq->lock);
485			__skb_queue_tail(arrvq, buf);
486			spin_unlock_bh(&inputq->lock);
487			node->action_flags |= TIPC_BCAST_MSG_EVT;
488			tipc_bclink_unlock(net);
489			tipc_node_unlock(node);
490		} else if (msg_user(msg) == MSG_BUNDLER) {
491			tipc_bclink_lock(net);
492			bclink_accept_pkt(node, seqno);
493			bcl->stats.recv_bundles++;
494			bcl->stats.recv_bundled += msg_msgcnt(msg);
495			pos = 0;
496			while (tipc_msg_extract(buf, &iskb, &pos)) {
497				spin_lock_bh(&inputq->lock);
498				__skb_queue_tail(arrvq, iskb);
499				spin_unlock_bh(&inputq->lock);
500			}
501			node->action_flags |= TIPC_BCAST_MSG_EVT;
502			tipc_bclink_unlock(net);
503			tipc_node_unlock(node);
504		} else if (msg_user(msg) == MSG_FRAGMENTER) {
505			tipc_bclink_lock(net);
506			bclink_accept_pkt(node, seqno);
507			tipc_buf_append(&node->bclink.reasm_buf, &buf);
508			if (unlikely(!buf && !node->bclink.reasm_buf)) {
509				tipc_bclink_unlock(net);
510				goto unlock;
511			}
512			bcl->stats.recv_fragments++;
513			if (buf) {
514				bcl->stats.recv_fragmented++;
515				msg = buf_msg(buf);
516				tipc_bclink_unlock(net);
517				goto receive;
518			}
519			tipc_bclink_unlock(net);
520			tipc_node_unlock(node);
521		} else {
522			tipc_bclink_lock(net);
523			bclink_accept_pkt(node, seqno);
524			tipc_bclink_unlock(net);
525			tipc_node_unlock(node);
526			kfree_skb(buf);
527		}
528		buf = NULL;
529
530		/* Determine new synchronization state */
531		tipc_node_lock(node);
532		if (unlikely(!tipc_node_is_up(node)))
533			goto unlock;
534
535		if (node->bclink.last_in == node->bclink.last_sent)
536			goto unlock;
537
538		if (skb_queue_empty(&node->bclink.deferdq)) {
539			node->bclink.oos_state = 1;
540			goto unlock;
541		}
542
543		msg = buf_msg(skb_peek(&node->bclink.deferdq));
544		seqno = msg_seqno(msg);
545		next_in = mod(next_in + 1);
546		if (seqno != next_in)
547			goto unlock;
548
549		/* Take in-sequence message from deferred queue & deliver it */
550		buf = __skb_dequeue(&node->bclink.deferdq);
551		goto receive;
552	}
553
554	/* Handle out-of-sequence broadcast message */
555	if (less(next_in, seqno)) {
556		deferred = tipc_link_defer_pkt(&node->bclink.deferdq,
557					       buf);
558		bclink_update_last_sent(node, seqno);
559		buf = NULL;
560	}
561
562	tipc_bclink_lock(net);
563
564	if (deferred)
565		bcl->stats.deferred_recv++;
566	else
567		bcl->stats.duplicates++;
568
569	tipc_bclink_unlock(net);
570
571unlock:
572	tipc_node_unlock(node);
573	tipc_node_put(node);
574exit:
575	kfree_skb(buf);
576}
577
578u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
579{
580	return (n_ptr->bclink.recv_permitted &&
581		(tipc_bclink_get_last_sent(n_ptr->net) != n_ptr->bclink.acked));
582}
583
584
585/**
586 * tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
587 *
588 * Send packet over as many bearers as necessary to reach all nodes
589 * that have joined the broadcast link.
590 *
591 * Returns 0 (packet sent successfully) under all circumstances,
592 * since the broadcast link's pseudo-bearer never blocks
593 */
594static int tipc_bcbearer_send(struct net *net, struct sk_buff *buf,
595			      struct tipc_bearer *unused1,
596			      struct tipc_media_addr *unused2)
597{
598	int bp_index;
599	struct tipc_msg *msg = buf_msg(buf);
600	struct tipc_net *tn = net_generic(net, tipc_net_id);
601	struct tipc_bcbearer *bcbearer = tn->bcbearer;
602	struct tipc_bclink *bclink = tn->bclink;
603
604	/* Prepare broadcast link message for reliable transmission,
605	 * if first time trying to send it;
606	 * preparation is skipped for broadcast link protocol messages
607	 * since they are sent in an unreliable manner and don't need it
608	 */
609	if (likely(!msg_non_seq(buf_msg(buf)))) {
610		bcbuf_set_acks(buf, bclink->bcast_nodes.count);
611		msg_set_non_seq(msg, 1);
612		msg_set_mc_netid(msg, tn->net_id);
613		tn->bcl->stats.sent_info++;
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	bcbearer->remains = bclink->bcast_nodes;
622
623	for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
624		struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
625		struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
626		struct tipc_bearer *bp[2] = {p, s};
627		struct tipc_bearer *b = bp[msg_link_selector(msg)];
628		struct sk_buff *tbuf;
629
630		if (!p)
631			break; /* No more bearers to try */
632		if (!b)
633			b = p;
634		tipc_nmap_diff(&bcbearer->remains, &b->nodes,
635			       &bcbearer->remains_new);
636		if (bcbearer->remains_new.count == bcbearer->remains.count)
637			continue; /* Nothing added by bearer pair */
638
639		if (bp_index == 0) {
640			/* Use original buffer for first bearer */
641			tipc_bearer_send(net, b->identity, buf, &b->bcast_addr);
642		} else {
643			/* Avoid concurrent buffer access */
644			tbuf = pskb_copy_for_clone(buf, GFP_ATOMIC);
645			if (!tbuf)
646				break;
647			tipc_bearer_send(net, b->identity, tbuf,
648					 &b->bcast_addr);
649			kfree_skb(tbuf); /* Bearer keeps a clone */
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 */
663void tipc_bcbearer_sort(struct net *net, struct tipc_node_map *nm_ptr,
664			u32 node, bool action)
665{
666	struct tipc_net *tn = net_generic(net, tipc_net_id);
667	struct tipc_bcbearer *bcbearer = tn->bcbearer;
668	struct tipc_bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
669	struct tipc_bcbearer_pair *bp_curr;
670	struct tipc_bearer *b;
671	int b_index;
672	int pri;
673
674	tipc_bclink_lock(net);
675
676	if (action)
677		tipc_nmap_add(nm_ptr, node);
678	else
679		tipc_nmap_remove(nm_ptr, node);
680
681	/* Group bearers by priority (can assume max of two per priority) */
682	memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
683
684	rcu_read_lock();
685	for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
686		b = rcu_dereference_rtnl(tn->bearer_list[b_index]);
687		if (!b || !b->nodes.count)
688			continue;
689
690		if (!bp_temp[b->priority].primary)
691			bp_temp[b->priority].primary = b;
692		else
693			bp_temp[b->priority].secondary = b;
694	}
695	rcu_read_unlock();
696
697	/* Create array of bearer pairs for broadcasting */
698	bp_curr = bcbearer->bpairs;
699	memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
700
701	for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
702
703		if (!bp_temp[pri].primary)
704			continue;
705
706		bp_curr->primary = bp_temp[pri].primary;
707
708		if (bp_temp[pri].secondary) {
709			if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
710					    &bp_temp[pri].secondary->nodes)) {
711				bp_curr->secondary = bp_temp[pri].secondary;
712			} else {
713				bp_curr++;
714				bp_curr->primary = bp_temp[pri].secondary;
715			}
716		}
717
718		bp_curr++;
719	}
720
721	tipc_bclink_unlock(net);
722}
723
724static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
725				      struct tipc_stats *stats)
726{
727	int i;
728	struct nlattr *nest;
729
730	struct nla_map {
731		__u32 key;
732		__u32 val;
733	};
734
735	struct nla_map map[] = {
736		{TIPC_NLA_STATS_RX_INFO, stats->recv_info},
737		{TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
738		{TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
739		{TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
740		{TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
741		{TIPC_NLA_STATS_TX_INFO, stats->sent_info},
742		{TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
743		{TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
744		{TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
745		{TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
746		{TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
747		{TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
748		{TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
749		{TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
750		{TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
751		{TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
752		{TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
753		{TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
754		{TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
755			(stats->accu_queue_sz / stats->queue_sz_counts) : 0}
756	};
757
758	nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
759	if (!nest)
760		return -EMSGSIZE;
761
762	for (i = 0; i <  ARRAY_SIZE(map); i++)
763		if (nla_put_u32(skb, map[i].key, map[i].val))
764			goto msg_full;
765
766	nla_nest_end(skb, nest);
767
768	return 0;
769msg_full:
770	nla_nest_cancel(skb, nest);
771
772	return -EMSGSIZE;
773}
774
775int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
776{
777	int err;
778	void *hdr;
779	struct nlattr *attrs;
780	struct nlattr *prop;
781	struct tipc_net *tn = net_generic(net, tipc_net_id);
782	struct tipc_link *bcl = tn->bcl;
783
784	if (!bcl)
785		return 0;
786
787	tipc_bclink_lock(net);
788
789	hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
790			  NLM_F_MULTI, TIPC_NL_LINK_GET);
791	if (!hdr)
792		return -EMSGSIZE;
793
794	attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
795	if (!attrs)
796		goto msg_full;
797
798	/* The broadcast link is always up */
799	if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
800		goto attr_msg_full;
801
802	if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
803		goto attr_msg_full;
804	if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
805		goto attr_msg_full;
806	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, bcl->next_in_no))
807		goto attr_msg_full;
808	if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, bcl->next_out_no))
809		goto attr_msg_full;
810
811	prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
812	if (!prop)
813		goto attr_msg_full;
814	if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
815		goto prop_msg_full;
816	nla_nest_end(msg->skb, prop);
817
818	err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
819	if (err)
820		goto attr_msg_full;
821
822	tipc_bclink_unlock(net);
823	nla_nest_end(msg->skb, attrs);
824	genlmsg_end(msg->skb, hdr);
825
826	return 0;
827
828prop_msg_full:
829	nla_nest_cancel(msg->skb, prop);
830attr_msg_full:
831	nla_nest_cancel(msg->skb, attrs);
832msg_full:
833	tipc_bclink_unlock(net);
834	genlmsg_cancel(msg->skb, hdr);
835
836	return -EMSGSIZE;
837}
838
839int tipc_bclink_reset_stats(struct net *net)
840{
841	struct tipc_net *tn = net_generic(net, tipc_net_id);
842	struct tipc_link *bcl = tn->bcl;
843
844	if (!bcl)
845		return -ENOPROTOOPT;
846
847	tipc_bclink_lock(net);
848	memset(&bcl->stats, 0, sizeof(bcl->stats));
849	tipc_bclink_unlock(net);
850	return 0;
851}
852
853int tipc_bclink_set_queue_limits(struct net *net, u32 limit)
854{
855	struct tipc_net *tn = net_generic(net, tipc_net_id);
856	struct tipc_link *bcl = tn->bcl;
857
858	if (!bcl)
859		return -ENOPROTOOPT;
860	if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
861		return -EINVAL;
862
863	tipc_bclink_lock(net);
864	tipc_link_set_queue_limits(bcl, limit);
865	tipc_bclink_unlock(net);
866	return 0;
867}
868
869int tipc_bclink_init(struct net *net)
870{
871	struct tipc_net *tn = net_generic(net, tipc_net_id);
872	struct tipc_bcbearer *bcbearer;
873	struct tipc_bclink *bclink;
874	struct tipc_link *bcl;
875
876	bcbearer = kzalloc(sizeof(*bcbearer), GFP_ATOMIC);
877	if (!bcbearer)
878		return -ENOMEM;
879
880	bclink = kzalloc(sizeof(*bclink), GFP_ATOMIC);
881	if (!bclink) {
882		kfree(bcbearer);
883		return -ENOMEM;
884	}
885
886	bcl = &bclink->link;
887	bcbearer->bearer.media = &bcbearer->media;
888	bcbearer->media.send_msg = tipc_bcbearer_send;
889	sprintf(bcbearer->media.name, "tipc-broadcast");
890
891	spin_lock_init(&bclink->lock);
892	__skb_queue_head_init(&bcl->transmq);
893	__skb_queue_head_init(&bcl->backlogq);
894	__skb_queue_head_init(&bcl->deferdq);
895	skb_queue_head_init(&bcl->wakeupq);
896	bcl->next_out_no = 1;
897	spin_lock_init(&bclink->node.lock);
898	__skb_queue_head_init(&bclink->arrvq);
899	skb_queue_head_init(&bclink->inputq);
900	bcl->owner = &bclink->node;
901	bcl->owner->net = net;
902	bcl->mtu = MAX_PKT_DEFAULT_MCAST;
903	tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
904	bcl->bearer_id = MAX_BEARERS;
905	rcu_assign_pointer(tn->bearer_list[MAX_BEARERS], &bcbearer->bearer);
906	bcl->state = WORKING_WORKING;
907	bcl->pmsg = (struct tipc_msg *)&bcl->proto_msg;
908	msg_set_prevnode(bcl->pmsg, tn->own_addr);
909	strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
910	tn->bcbearer = bcbearer;
911	tn->bclink = bclink;
912	tn->bcl = bcl;
913	return 0;
914}
915
916void tipc_bclink_stop(struct net *net)
917{
918	struct tipc_net *tn = net_generic(net, tipc_net_id);
919
920	tipc_bclink_lock(net);
921	tipc_link_purge_queues(tn->bcl);
922	tipc_bclink_unlock(net);
923
924	RCU_INIT_POINTER(tn->bearer_list[BCBEARER], NULL);
925	synchronize_net();
926	kfree(tn->bcbearer);
927	kfree(tn->bclink);
928}
929
930/**
931 * tipc_nmap_add - add a node to a node map
932 */
933static void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node)
934{
935	int n = tipc_node(node);
936	int w = n / WSIZE;
937	u32 mask = (1 << (n % WSIZE));
938
939	if ((nm_ptr->map[w] & mask) == 0) {
940		nm_ptr->count++;
941		nm_ptr->map[w] |= mask;
942	}
943}
944
945/**
946 * tipc_nmap_remove - remove a node from a node map
947 */
948static void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node)
949{
950	int n = tipc_node(node);
951	int w = n / WSIZE;
952	u32 mask = (1 << (n % WSIZE));
953
954	if ((nm_ptr->map[w] & mask) != 0) {
955		nm_ptr->map[w] &= ~mask;
956		nm_ptr->count--;
957	}
958}
959
960/**
961 * tipc_nmap_diff - find differences between node maps
962 * @nm_a: input node map A
963 * @nm_b: input node map B
964 * @nm_diff: output node map A-B (i.e. nodes of A that are not in B)
965 */
966static void tipc_nmap_diff(struct tipc_node_map *nm_a,
967			   struct tipc_node_map *nm_b,
968			   struct tipc_node_map *nm_diff)
969{
970	int stop = ARRAY_SIZE(nm_a->map);
971	int w;
972	int b;
973	u32 map;
974
975	memset(nm_diff, 0, sizeof(*nm_diff));
976	for (w = 0; w < stop; w++) {
977		map = nm_a->map[w] ^ (nm_a->map[w] & nm_b->map[w]);
978		nm_diff->map[w] = map;
979		if (map != 0) {
980			for (b = 0 ; b < WSIZE; b++) {
981				if (map & (1 << b))
982					nm_diff->count++;
983			}
984		}
985	}
986}
987