Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux...
[firefly-linux-kernel-4.4.55.git] / net / tipc / bcast.c
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 struct tipc_bcbearer {
77         struct tipc_bearer bearer;
78         struct tipc_media media;
79         struct tipc_bcbearer_pair bpairs[MAX_BEARERS];
80         struct tipc_bcbearer_pair bpairs_temp[TIPC_MAX_LINK_PRI + 1];
81         struct tipc_node_map remains;
82         struct tipc_node_map remains_new;
83 };
84
85 /**
86  * struct tipc_bclink - link used for broadcast messages
87  * @link: (non-standard) broadcast link structure
88  * @node: (non-standard) node structure representing b'cast link's peer node
89  * @bcast_nodes: map of broadcast-capable nodes
90  * @retransmit_to: node that most recently requested a retransmit
91  *
92  * Handles sequence numbering, fragmentation, bundling, etc.
93  */
94 struct tipc_bclink {
95         struct tipc_link link;
96         struct tipc_node node;
97         struct tipc_node_map bcast_nodes;
98         struct tipc_node *retransmit_to;
99 };
100
101 static struct tipc_bcbearer bcast_bearer;
102 static struct tipc_bclink bcast_link;
103
104 static struct tipc_bcbearer *bcbearer = &bcast_bearer;
105 static struct tipc_bclink *bclink = &bcast_link;
106 static struct tipc_link *bcl = &bcast_link.link;
107
108 static DEFINE_SPINLOCK(bc_lock);
109
110 const char tipc_bclink_name[] = "broadcast-link";
111
112 static void tipc_nmap_diff(struct tipc_node_map *nm_a,
113                            struct tipc_node_map *nm_b,
114                            struct tipc_node_map *nm_diff);
115
116 static u32 bcbuf_acks(struct sk_buff *buf)
117 {
118         return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
119 }
120
121 static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
122 {
123         TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
124 }
125
126 static void bcbuf_decr_acks(struct sk_buff *buf)
127 {
128         bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
129 }
130
131 void tipc_bclink_add_node(u32 addr)
132 {
133         spin_lock_bh(&bc_lock);
134         tipc_nmap_add(&bclink->bcast_nodes, addr);
135         spin_unlock_bh(&bc_lock);
136 }
137
138 void tipc_bclink_remove_node(u32 addr)
139 {
140         spin_lock_bh(&bc_lock);
141         tipc_nmap_remove(&bclink->bcast_nodes, addr);
142         spin_unlock_bh(&bc_lock);
143 }
144
145 static void bclink_set_last_sent(void)
146 {
147         if (bcl->next_out)
148                 bcl->fsm_msg_cnt = mod(buf_seqno(bcl->next_out) - 1);
149         else
150                 bcl->fsm_msg_cnt = mod(bcl->next_out_no - 1);
151 }
152
153 u32 tipc_bclink_get_last_sent(void)
154 {
155         return bcl->fsm_msg_cnt;
156 }
157
158 static void bclink_update_last_sent(struct tipc_node *node, u32 seqno)
159 {
160         node->bclink.last_sent = less_eq(node->bclink.last_sent, seqno) ?
161                                                 seqno : node->bclink.last_sent;
162 }
163
164
165 /*
166  * tipc_bclink_retransmit_to - get most recent node to request retransmission
167  *
168  * Called with bc_lock locked
169  */
170 struct tipc_node *tipc_bclink_retransmit_to(void)
171 {
172         return bclink->retransmit_to;
173 }
174
175 /**
176  * bclink_retransmit_pkt - retransmit broadcast packets
177  * @after: sequence number of last packet to *not* retransmit
178  * @to: sequence number of last packet to retransmit
179  *
180  * Called with bc_lock locked
181  */
182 static void bclink_retransmit_pkt(u32 after, u32 to)
183 {
184         struct sk_buff *buf;
185
186         buf = bcl->first_out;
187         while (buf && less_eq(buf_seqno(buf), after))
188                 buf = buf->next;
189         tipc_link_retransmit(bcl, buf, mod(to - after));
190 }
191
192 /**
193  * tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
194  * @n_ptr: node that sent acknowledgement info
195  * @acked: broadcast sequence # that has been acknowledged
196  *
197  * Node is locked, bc_lock unlocked.
198  */
199 void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
200 {
201         struct sk_buff *crs;
202         struct sk_buff *next;
203         unsigned int released = 0;
204
205         spin_lock_bh(&bc_lock);
206
207         /* Bail out if tx queue is empty (no clean up is required) */
208         crs = bcl->first_out;
209         if (!crs)
210                 goto exit;
211
212         /* Determine which messages need to be acknowledged */
213         if (acked == INVALID_LINK_SEQ) {
214                 /*
215                  * Contact with specified node has been lost, so need to
216                  * acknowledge sent messages only (if other nodes still exist)
217                  * or both sent and unsent messages (otherwise)
218                  */
219                 if (bclink->bcast_nodes.count)
220                         acked = bcl->fsm_msg_cnt;
221                 else
222                         acked = bcl->next_out_no;
223         } else {
224                 /*
225                  * Bail out if specified sequence number does not correspond
226                  * to a message that has been sent and not yet acknowledged
227                  */
228                 if (less(acked, buf_seqno(crs)) ||
229                     less(bcl->fsm_msg_cnt, acked) ||
230                     less_eq(acked, n_ptr->bclink.acked))
231                         goto exit;
232         }
233
234         /* Skip over packets that node has previously acknowledged */
235         while (crs && less_eq(buf_seqno(crs), n_ptr->bclink.acked))
236                 crs = crs->next;
237
238         /* Update packets that node is now acknowledging */
239
240         while (crs && less_eq(buf_seqno(crs), acked)) {
241                 next = crs->next;
242
243                 if (crs != bcl->next_out)
244                         bcbuf_decr_acks(crs);
245                 else {
246                         bcbuf_set_acks(crs, 0);
247                         bcl->next_out = next;
248                         bclink_set_last_sent();
249                 }
250
251                 if (bcbuf_acks(crs) == 0) {
252                         bcl->first_out = next;
253                         bcl->out_queue_size--;
254                         kfree_skb(crs);
255                         released = 1;
256                 }
257                 crs = next;
258         }
259         n_ptr->bclink.acked = acked;
260
261         /* Try resolving broadcast link congestion, if necessary */
262
263         if (unlikely(bcl->next_out)) {
264                 tipc_link_push_queue(bcl);
265                 bclink_set_last_sent();
266         }
267         if (unlikely(released && !list_empty(&bcl->waiting_ports)))
268                 tipc_link_wakeup_ports(bcl, 0);
269 exit:
270         spin_unlock_bh(&bc_lock);
271 }
272
273 /*
274  * tipc_bclink_update_link_state - update broadcast link state
275  *
276  * tipc_net_lock and node lock set
277  */
278 void tipc_bclink_update_link_state(struct tipc_node *n_ptr, u32 last_sent)
279 {
280         struct sk_buff *buf;
281
282         /* Ignore "stale" link state info */
283
284         if (less_eq(last_sent, n_ptr->bclink.last_in))
285                 return;
286
287         /* Update link synchronization state; quit if in sync */
288
289         bclink_update_last_sent(n_ptr, last_sent);
290
291         if (n_ptr->bclink.last_sent == n_ptr->bclink.last_in)
292                 return;
293
294         /* Update out-of-sync state; quit if loss is still unconfirmed */
295
296         if ((++n_ptr->bclink.oos_state) == 1) {
297                 if (n_ptr->bclink.deferred_size < (TIPC_MIN_LINK_WIN / 2))
298                         return;
299                 n_ptr->bclink.oos_state++;
300         }
301
302         /* Don't NACK if one has been recently sent (or seen) */
303
304         if (n_ptr->bclink.oos_state & 0x1)
305                 return;
306
307         /* Send NACK */
308
309         buf = tipc_buf_acquire(INT_H_SIZE);
310         if (buf) {
311                 struct tipc_msg *msg = buf_msg(buf);
312
313                 tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG,
314                               INT_H_SIZE, n_ptr->addr);
315                 msg_set_non_seq(msg, 1);
316                 msg_set_mc_netid(msg, tipc_net_id);
317                 msg_set_bcast_ack(msg, n_ptr->bclink.last_in);
318                 msg_set_bcgap_after(msg, n_ptr->bclink.last_in);
319                 msg_set_bcgap_to(msg, n_ptr->bclink.deferred_head
320                                  ? buf_seqno(n_ptr->bclink.deferred_head) - 1
321                                  : n_ptr->bclink.last_sent);
322
323                 spin_lock_bh(&bc_lock);
324                 tipc_bearer_send(&bcbearer->bearer, buf, NULL);
325                 bcl->stats.sent_nacks++;
326                 spin_unlock_bh(&bc_lock);
327                 kfree_skb(buf);
328
329                 n_ptr->bclink.oos_state++;
330         }
331 }
332
333 /*
334  * bclink_peek_nack - monitor retransmission requests sent by other nodes
335  *
336  * Delay any upcoming NACK by this node if another node has already
337  * requested the first message this node is going to ask for.
338  *
339  * Only tipc_net_lock set.
340  */
341 static void bclink_peek_nack(struct tipc_msg *msg)
342 {
343         struct tipc_node *n_ptr = tipc_node_find(msg_destnode(msg));
344
345         if (unlikely(!n_ptr))
346                 return;
347
348         tipc_node_lock(n_ptr);
349
350         if (n_ptr->bclink.supported &&
351             (n_ptr->bclink.last_in != n_ptr->bclink.last_sent) &&
352             (n_ptr->bclink.last_in == msg_bcgap_after(msg)))
353                 n_ptr->bclink.oos_state = 2;
354
355         tipc_node_unlock(n_ptr);
356 }
357
358 /*
359  * tipc_bclink_send_msg - broadcast a packet to all nodes in cluster
360  */
361 int tipc_bclink_send_msg(struct sk_buff *buf)
362 {
363         int res;
364
365         spin_lock_bh(&bc_lock);
366
367         if (!bclink->bcast_nodes.count) {
368                 res = msg_data_sz(buf_msg(buf));
369                 kfree_skb(buf);
370                 goto exit;
371         }
372
373         res = tipc_link_send_buf(bcl, buf);
374         if (likely(res >= 0)) {
375                 bclink_set_last_sent();
376                 bcl->stats.queue_sz_counts++;
377                 bcl->stats.accu_queue_sz += bcl->out_queue_size;
378         }
379 exit:
380         spin_unlock_bh(&bc_lock);
381         return res;
382 }
383
384 /*
385  * bclink_accept_pkt - accept an incoming, in-sequence broadcast packet
386  *
387  * Called with both sending node's lock and bc_lock taken.
388  */
389 static void bclink_accept_pkt(struct tipc_node *node, u32 seqno)
390 {
391         bclink_update_last_sent(node, seqno);
392         node->bclink.last_in = seqno;
393         node->bclink.oos_state = 0;
394         bcl->stats.recv_info++;
395
396         /*
397          * Unicast an ACK periodically, ensuring that
398          * all nodes in the cluster don't ACK at the same time
399          */
400
401         if (((seqno - tipc_own_addr) % TIPC_MIN_LINK_WIN) == 0) {
402                 tipc_link_send_proto_msg(
403                         node->active_links[node->addr & 1],
404                         STATE_MSG, 0, 0, 0, 0, 0);
405                 bcl->stats.sent_acks++;
406         }
407 }
408
409 /*
410  * tipc_bclink_recv_pkt - receive a broadcast packet, and deliver upwards
411  *
412  * tipc_net_lock is read_locked, no other locks set
413  */
414 void tipc_bclink_recv_pkt(struct sk_buff *buf)
415 {
416         struct tipc_msg *msg = buf_msg(buf);
417         struct tipc_node *node;
418         u32 next_in;
419         u32 seqno;
420         int deferred;
421
422         /* Screen out unwanted broadcast messages */
423
424         if (msg_mc_netid(msg) != tipc_net_id)
425                 goto exit;
426
427         node = tipc_node_find(msg_prevnode(msg));
428         if (unlikely(!node))
429                 goto exit;
430
431         tipc_node_lock(node);
432         if (unlikely(!node->bclink.supported))
433                 goto unlock;
434
435         /* Handle broadcast protocol message */
436
437         if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) {
438                 if (msg_type(msg) != STATE_MSG)
439                         goto unlock;
440                 if (msg_destnode(msg) == tipc_own_addr) {
441                         tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
442                         tipc_node_unlock(node);
443                         spin_lock_bh(&bc_lock);
444                         bcl->stats.recv_nacks++;
445                         bclink->retransmit_to = node;
446                         bclink_retransmit_pkt(msg_bcgap_after(msg),
447                                               msg_bcgap_to(msg));
448                         spin_unlock_bh(&bc_lock);
449                 } else {
450                         tipc_node_unlock(node);
451                         bclink_peek_nack(msg);
452                 }
453                 goto exit;
454         }
455
456         /* Handle in-sequence broadcast message */
457
458         seqno = msg_seqno(msg);
459         next_in = mod(node->bclink.last_in + 1);
460
461         if (likely(seqno == next_in)) {
462 receive:
463                 /* Deliver message to destination */
464
465                 if (likely(msg_isdata(msg))) {
466                         spin_lock_bh(&bc_lock);
467                         bclink_accept_pkt(node, seqno);
468                         spin_unlock_bh(&bc_lock);
469                         tipc_node_unlock(node);
470                         if (likely(msg_mcast(msg)))
471                                 tipc_port_recv_mcast(buf, NULL);
472                         else
473                                 kfree_skb(buf);
474                 } else if (msg_user(msg) == MSG_BUNDLER) {
475                         spin_lock_bh(&bc_lock);
476                         bclink_accept_pkt(node, seqno);
477                         bcl->stats.recv_bundles++;
478                         bcl->stats.recv_bundled += msg_msgcnt(msg);
479                         spin_unlock_bh(&bc_lock);
480                         tipc_node_unlock(node);
481                         tipc_link_recv_bundle(buf);
482                 } else if (msg_user(msg) == MSG_FRAGMENTER) {
483                         int ret = tipc_link_recv_fragment(&node->bclink.defragm,
484                                                       &buf, &msg);
485                         if (ret < 0)
486                                 goto unlock;
487                         spin_lock_bh(&bc_lock);
488                         bclink_accept_pkt(node, seqno);
489                         bcl->stats.recv_fragments++;
490                         if (ret > 0)
491                                 bcl->stats.recv_fragmented++;
492                         spin_unlock_bh(&bc_lock);
493                         tipc_node_unlock(node);
494                         tipc_net_route_msg(buf);
495                 } else if (msg_user(msg) == NAME_DISTRIBUTOR) {
496                         spin_lock_bh(&bc_lock);
497                         bclink_accept_pkt(node, seqno);
498                         spin_unlock_bh(&bc_lock);
499                         tipc_node_unlock(node);
500                         tipc_named_recv(buf);
501                 } else {
502                         spin_lock_bh(&bc_lock);
503                         bclink_accept_pkt(node, seqno);
504                         spin_unlock_bh(&bc_lock);
505                         tipc_node_unlock(node);
506                         kfree_skb(buf);
507                 }
508                 buf = NULL;
509
510                 /* Determine new synchronization state */
511
512                 tipc_node_lock(node);
513                 if (unlikely(!tipc_node_is_up(node)))
514                         goto unlock;
515
516                 if (node->bclink.last_in == node->bclink.last_sent)
517                         goto unlock;
518
519                 if (!node->bclink.deferred_head) {
520                         node->bclink.oos_state = 1;
521                         goto unlock;
522                 }
523
524                 msg = buf_msg(node->bclink.deferred_head);
525                 seqno = msg_seqno(msg);
526                 next_in = mod(next_in + 1);
527                 if (seqno != next_in)
528                         goto unlock;
529
530                 /* Take in-sequence message from deferred queue & deliver it */
531
532                 buf = node->bclink.deferred_head;
533                 node->bclink.deferred_head = buf->next;
534                 node->bclink.deferred_size--;
535                 goto receive;
536         }
537
538         /* Handle out-of-sequence broadcast message */
539
540         if (less(next_in, seqno)) {
541                 deferred = tipc_link_defer_pkt(&node->bclink.deferred_head,
542                                                &node->bclink.deferred_tail,
543                                                buf);
544                 node->bclink.deferred_size += deferred;
545                 bclink_update_last_sent(node, seqno);
546                 buf = NULL;
547         } else
548                 deferred = 0;
549
550         spin_lock_bh(&bc_lock);
551
552         if (deferred)
553                 bcl->stats.deferred_recv++;
554         else
555                 bcl->stats.duplicates++;
556
557         spin_unlock_bh(&bc_lock);
558
559 unlock:
560         tipc_node_unlock(node);
561 exit:
562         kfree_skb(buf);
563 }
564
565 u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
566 {
567         return (n_ptr->bclink.supported &&
568                 (tipc_bclink_get_last_sent() != n_ptr->bclink.acked));
569 }
570
571
572 /**
573  * tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
574  *
575  * Send packet over as many bearers as necessary to reach all nodes
576  * that have joined the broadcast link.
577  *
578  * Returns 0 (packet sent successfully) under all circumstances,
579  * since the broadcast link's pseudo-bearer never blocks
580  */
581 static int tipc_bcbearer_send(struct sk_buff *buf,
582                               struct tipc_bearer *unused1,
583                               struct tipc_media_addr *unused2)
584 {
585         int bp_index;
586
587         /*
588          * Prepare broadcast link message for reliable transmission,
589          * if first time trying to send it;
590          * preparation is skipped for broadcast link protocol messages
591          * since they are sent in an unreliable manner and don't need it
592          */
593         if (likely(!msg_non_seq(buf_msg(buf)))) {
594                 struct tipc_msg *msg;
595
596                 bcbuf_set_acks(buf, bclink->bcast_nodes.count);
597                 msg = buf_msg(buf);
598                 msg_set_non_seq(msg, 1);
599                 msg_set_mc_netid(msg, tipc_net_id);
600                 bcl->stats.sent_info++;
601
602                 if (WARN_ON(!bclink->bcast_nodes.count)) {
603                         dump_stack();
604                         return 0;
605                 }
606         }
607
608         /* Send buffer over bearers until all targets reached */
609         bcbearer->remains = bclink->bcast_nodes;
610
611         for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
612                 struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
613                 struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
614
615                 if (!p)
616                         break;  /* no more bearers to try */
617
618                 tipc_nmap_diff(&bcbearer->remains, &p->nodes, &bcbearer->remains_new);
619                 if (bcbearer->remains_new.count == bcbearer->remains.count)
620                         continue;       /* bearer pair doesn't add anything */
621
622                 if (p->blocked ||
623                     p->media->send_msg(buf, p, &p->media->bcast_addr)) {
624                         /* unable to send on primary bearer */
625                         if (!s || s->blocked ||
626                             s->media->send_msg(buf, s,
627                                                &s->media->bcast_addr)) {
628                                 /* unable to send on either bearer */
629                                 continue;
630                         }
631                 }
632
633                 if (s) {
634                         bcbearer->bpairs[bp_index].primary = s;
635                         bcbearer->bpairs[bp_index].secondary = p;
636                 }
637
638                 if (bcbearer->remains_new.count == 0)
639                         break;  /* all targets reached */
640
641                 bcbearer->remains = bcbearer->remains_new;
642         }
643
644         return 0;
645 }
646
647 /**
648  * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
649  */
650 void tipc_bcbearer_sort(void)
651 {
652         struct tipc_bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
653         struct tipc_bcbearer_pair *bp_curr;
654         int b_index;
655         int pri;
656
657         spin_lock_bh(&bc_lock);
658
659         /* Group bearers by priority (can assume max of two per priority) */
660         memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
661
662         for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
663                 struct tipc_bearer *b = &tipc_bearers[b_index];
664
665                 if (!b->active || !b->nodes.count)
666                         continue;
667
668                 if (!bp_temp[b->priority].primary)
669                         bp_temp[b->priority].primary = b;
670                 else
671                         bp_temp[b->priority].secondary = b;
672         }
673
674         /* Create array of bearer pairs for broadcasting */
675         bp_curr = bcbearer->bpairs;
676         memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
677
678         for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
679
680                 if (!bp_temp[pri].primary)
681                         continue;
682
683                 bp_curr->primary = bp_temp[pri].primary;
684
685                 if (bp_temp[pri].secondary) {
686                         if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
687                                             &bp_temp[pri].secondary->nodes)) {
688                                 bp_curr->secondary = bp_temp[pri].secondary;
689                         } else {
690                                 bp_curr++;
691                                 bp_curr->primary = bp_temp[pri].secondary;
692                         }
693                 }
694
695                 bp_curr++;
696         }
697
698         spin_unlock_bh(&bc_lock);
699 }
700
701
702 int tipc_bclink_stats(char *buf, const u32 buf_size)
703 {
704         struct print_buf pb;
705
706         if (!bcl)
707                 return 0;
708
709         tipc_printbuf_init(&pb, buf, buf_size);
710
711         spin_lock_bh(&bc_lock);
712
713         tipc_printf(&pb, "Link <%s>\n"
714                          "  Window:%u packets\n",
715                     bcl->name, bcl->queue_limit[0]);
716         tipc_printf(&pb, "  RX packets:%u fragments:%u/%u bundles:%u/%u\n",
717                     bcl->stats.recv_info,
718                     bcl->stats.recv_fragments,
719                     bcl->stats.recv_fragmented,
720                     bcl->stats.recv_bundles,
721                     bcl->stats.recv_bundled);
722         tipc_printf(&pb, "  TX packets:%u fragments:%u/%u bundles:%u/%u\n",
723                     bcl->stats.sent_info,
724                     bcl->stats.sent_fragments,
725                     bcl->stats.sent_fragmented,
726                     bcl->stats.sent_bundles,
727                     bcl->stats.sent_bundled);
728         tipc_printf(&pb, "  RX naks:%u defs:%u dups:%u\n",
729                     bcl->stats.recv_nacks,
730                     bcl->stats.deferred_recv,
731                     bcl->stats.duplicates);
732         tipc_printf(&pb, "  TX naks:%u acks:%u dups:%u\n",
733                     bcl->stats.sent_nacks,
734                     bcl->stats.sent_acks,
735                     bcl->stats.retransmitted);
736         tipc_printf(&pb, "  Congestion bearer:%u link:%u  Send queue max:%u avg:%u\n",
737                     bcl->stats.bearer_congs,
738                     bcl->stats.link_congs,
739                     bcl->stats.max_queue_sz,
740                     bcl->stats.queue_sz_counts
741                     ? (bcl->stats.accu_queue_sz / bcl->stats.queue_sz_counts)
742                     : 0);
743
744         spin_unlock_bh(&bc_lock);
745         return tipc_printbuf_validate(&pb);
746 }
747
748 int tipc_bclink_reset_stats(void)
749 {
750         if (!bcl)
751                 return -ENOPROTOOPT;
752
753         spin_lock_bh(&bc_lock);
754         memset(&bcl->stats, 0, sizeof(bcl->stats));
755         spin_unlock_bh(&bc_lock);
756         return 0;
757 }
758
759 int tipc_bclink_set_queue_limits(u32 limit)
760 {
761         if (!bcl)
762                 return -ENOPROTOOPT;
763         if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
764                 return -EINVAL;
765
766         spin_lock_bh(&bc_lock);
767         tipc_link_set_queue_limits(bcl, limit);
768         spin_unlock_bh(&bc_lock);
769         return 0;
770 }
771
772 void tipc_bclink_init(void)
773 {
774         INIT_LIST_HEAD(&bcbearer->bearer.cong_links);
775         bcbearer->bearer.media = &bcbearer->media;
776         bcbearer->media.send_msg = tipc_bcbearer_send;
777         sprintf(bcbearer->media.name, "tipc-broadcast");
778
779         INIT_LIST_HEAD(&bcl->waiting_ports);
780         bcl->next_out_no = 1;
781         spin_lock_init(&bclink->node.lock);
782         bcl->owner = &bclink->node;
783         bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
784         tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
785         bcl->b_ptr = &bcbearer->bearer;
786         bcl->state = WORKING_WORKING;
787         strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
788 }
789
790 void tipc_bclink_stop(void)
791 {
792         spin_lock_bh(&bc_lock);
793         tipc_link_stop(bcl);
794         spin_unlock_bh(&bc_lock);
795
796         memset(bclink, 0, sizeof(*bclink));
797         memset(bcbearer, 0, sizeof(*bcbearer));
798 }
799
800
801 /**
802  * tipc_nmap_add - add a node to a node map
803  */
804 void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node)
805 {
806         int n = tipc_node(node);
807         int w = n / WSIZE;
808         u32 mask = (1 << (n % WSIZE));
809
810         if ((nm_ptr->map[w] & mask) == 0) {
811                 nm_ptr->count++;
812                 nm_ptr->map[w] |= mask;
813         }
814 }
815
816 /**
817  * tipc_nmap_remove - remove a node from a node map
818  */
819 void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node)
820 {
821         int n = tipc_node(node);
822         int w = n / WSIZE;
823         u32 mask = (1 << (n % WSIZE));
824
825         if ((nm_ptr->map[w] & mask) != 0) {
826                 nm_ptr->map[w] &= ~mask;
827                 nm_ptr->count--;
828         }
829 }
830
831 /**
832  * tipc_nmap_diff - find differences between node maps
833  * @nm_a: input node map A
834  * @nm_b: input node map B
835  * @nm_diff: output node map A-B (i.e. nodes of A that are not in B)
836  */
837 static void tipc_nmap_diff(struct tipc_node_map *nm_a,
838                            struct tipc_node_map *nm_b,
839                            struct tipc_node_map *nm_diff)
840 {
841         int stop = ARRAY_SIZE(nm_a->map);
842         int w;
843         int b;
844         u32 map;
845
846         memset(nm_diff, 0, sizeof(*nm_diff));
847         for (w = 0; w < stop; w++) {
848                 map = nm_a->map[w] ^ (nm_a->map[w] & nm_b->map[w]);
849                 nm_diff->map[w] = map;
850                 if (map != 0) {
851                         for (b = 0 ; b < WSIZE; b++) {
852                                 if (map & (1 << b))
853                                         nm_diff->count++;
854                         }
855                 }
856         }
857 }
858
859 /**
860  * tipc_port_list_add - add a port to a port list, ensuring no duplicates
861  */
862 void tipc_port_list_add(struct tipc_port_list *pl_ptr, u32 port)
863 {
864         struct tipc_port_list *item = pl_ptr;
865         int i;
866         int item_sz = PLSIZE;
867         int cnt = pl_ptr->count;
868
869         for (; ; cnt -= item_sz, item = item->next) {
870                 if (cnt < PLSIZE)
871                         item_sz = cnt;
872                 for (i = 0; i < item_sz; i++)
873                         if (item->ports[i] == port)
874                                 return;
875                 if (i < PLSIZE) {
876                         item->ports[i] = port;
877                         pl_ptr->count++;
878                         return;
879                 }
880                 if (!item->next) {
881                         item->next = kmalloc(sizeof(*item), GFP_ATOMIC);
882                         if (!item->next) {
883                                 warn("Incomplete multicast delivery, no memory\n");
884                                 return;
885                         }
886                         item->next->next = NULL;
887                 }
888         }
889 }
890
891 /**
892  * tipc_port_list_free - free dynamically created entries in port_list chain
893  *
894  */
895 void tipc_port_list_free(struct tipc_port_list *pl_ptr)
896 {
897         struct tipc_port_list *item;
898         struct tipc_port_list *next;
899
900         for (item = pl_ptr->next; item; item = next) {
901                 next = item->next;
902                 kfree(item);
903         }
904 }