xref: /openbmc/linux/net/tipc/bcast.c (revision 9d749629)
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.recv_permitted &&
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.recv_permitted))
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.recv_permitted &&
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 (!tipc_bearer_blocked(p))
623  			tipc_bearer_send(p, buf, &p->media->bcast_addr);
624  		else if (s && !tipc_bearer_blocked(s))
625  			/* unable to send on primary bearer */
626  			tipc_bearer_send(s, buf, &s->media->bcast_addr);
627  		else
628  			/* unable to send on either bearer */
629  			continue;
630  
631  		if (s) {
632  			bcbearer->bpairs[bp_index].primary = s;
633  			bcbearer->bpairs[bp_index].secondary = p;
634  		}
635  
636  		if (bcbearer->remains_new.count == 0)
637  			break;	/* all targets reached */
638  
639  		bcbearer->remains = bcbearer->remains_new;
640  	}
641  
642  	return 0;
643  }
644  
645  /**
646   * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
647   */
648  void tipc_bcbearer_sort(void)
649  {
650  	struct tipc_bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
651  	struct tipc_bcbearer_pair *bp_curr;
652  	int b_index;
653  	int pri;
654  
655  	spin_lock_bh(&bc_lock);
656  
657  	/* Group bearers by priority (can assume max of two per priority) */
658  	memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
659  
660  	for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
661  		struct tipc_bearer *b = &tipc_bearers[b_index];
662  
663  		if (!b->active || !b->nodes.count)
664  			continue;
665  
666  		if (!bp_temp[b->priority].primary)
667  			bp_temp[b->priority].primary = b;
668  		else
669  			bp_temp[b->priority].secondary = b;
670  	}
671  
672  	/* Create array of bearer pairs for broadcasting */
673  	bp_curr = bcbearer->bpairs;
674  	memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
675  
676  	for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
677  
678  		if (!bp_temp[pri].primary)
679  			continue;
680  
681  		bp_curr->primary = bp_temp[pri].primary;
682  
683  		if (bp_temp[pri].secondary) {
684  			if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
685  					    &bp_temp[pri].secondary->nodes)) {
686  				bp_curr->secondary = bp_temp[pri].secondary;
687  			} else {
688  				bp_curr++;
689  				bp_curr->primary = bp_temp[pri].secondary;
690  			}
691  		}
692  
693  		bp_curr++;
694  	}
695  
696  	spin_unlock_bh(&bc_lock);
697  }
698  
699  
700  int tipc_bclink_stats(char *buf, const u32 buf_size)
701  {
702  	int ret;
703  	struct tipc_stats *s;
704  
705  	if (!bcl)
706  		return 0;
707  
708  	spin_lock_bh(&bc_lock);
709  
710  	s = &bcl->stats;
711  
712  	ret = tipc_snprintf(buf, buf_size, "Link <%s>\n"
713  			    "  Window:%u packets\n",
714  			    bcl->name, bcl->queue_limit[0]);
715  	ret += tipc_snprintf(buf + ret, buf_size - ret,
716  			     "  RX packets:%u fragments:%u/%u bundles:%u/%u\n",
717  			     s->recv_info, s->recv_fragments,
718  			     s->recv_fragmented, s->recv_bundles,
719  			     s->recv_bundled);
720  	ret += tipc_snprintf(buf + ret, buf_size - ret,
721  			     "  TX packets:%u fragments:%u/%u bundles:%u/%u\n",
722  			     s->sent_info, s->sent_fragments,
723  			     s->sent_fragmented, s->sent_bundles,
724  			     s->sent_bundled);
725  	ret += tipc_snprintf(buf + ret, buf_size - ret,
726  			     "  RX naks:%u defs:%u dups:%u\n",
727  			     s->recv_nacks, s->deferred_recv, s->duplicates);
728  	ret += tipc_snprintf(buf + ret, buf_size - ret,
729  			     "  TX naks:%u acks:%u dups:%u\n",
730  			     s->sent_nacks, s->sent_acks, s->retransmitted);
731  	ret += tipc_snprintf(buf + ret, buf_size - ret,
732  			     "  Congestion link:%u  Send queue max:%u avg:%u\n",
733  			     s->link_congs, s->max_queue_sz,
734  			     s->queue_sz_counts ?
735  			     (s->accu_queue_sz / s->queue_sz_counts) : 0);
736  
737  	spin_unlock_bh(&bc_lock);
738  	return ret;
739  }
740  
741  int tipc_bclink_reset_stats(void)
742  {
743  	if (!bcl)
744  		return -ENOPROTOOPT;
745  
746  	spin_lock_bh(&bc_lock);
747  	memset(&bcl->stats, 0, sizeof(bcl->stats));
748  	spin_unlock_bh(&bc_lock);
749  	return 0;
750  }
751  
752  int tipc_bclink_set_queue_limits(u32 limit)
753  {
754  	if (!bcl)
755  		return -ENOPROTOOPT;
756  	if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
757  		return -EINVAL;
758  
759  	spin_lock_bh(&bc_lock);
760  	tipc_link_set_queue_limits(bcl, limit);
761  	spin_unlock_bh(&bc_lock);
762  	return 0;
763  }
764  
765  void tipc_bclink_init(void)
766  {
767  	bcbearer->bearer.media = &bcbearer->media;
768  	bcbearer->media.send_msg = tipc_bcbearer_send;
769  	sprintf(bcbearer->media.name, "tipc-broadcast");
770  
771  	INIT_LIST_HEAD(&bcl->waiting_ports);
772  	bcl->next_out_no = 1;
773  	spin_lock_init(&bclink->node.lock);
774  	bcl->owner = &bclink->node;
775  	bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
776  	tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
777  	spin_lock_init(&bcbearer->bearer.lock);
778  	bcl->b_ptr = &bcbearer->bearer;
779  	bcl->state = WORKING_WORKING;
780  	strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
781  }
782  
783  void tipc_bclink_stop(void)
784  {
785  	spin_lock_bh(&bc_lock);
786  	tipc_link_stop(bcl);
787  	spin_unlock_bh(&bc_lock);
788  
789  	memset(bclink, 0, sizeof(*bclink));
790  	memset(bcbearer, 0, sizeof(*bcbearer));
791  }
792  
793  
794  /**
795   * tipc_nmap_add - add a node to a node map
796   */
797  void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node)
798  {
799  	int n = tipc_node(node);
800  	int w = n / WSIZE;
801  	u32 mask = (1 << (n % WSIZE));
802  
803  	if ((nm_ptr->map[w] & mask) == 0) {
804  		nm_ptr->count++;
805  		nm_ptr->map[w] |= mask;
806  	}
807  }
808  
809  /**
810   * tipc_nmap_remove - remove a node from a node map
811   */
812  void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node)
813  {
814  	int n = tipc_node(node);
815  	int w = n / WSIZE;
816  	u32 mask = (1 << (n % WSIZE));
817  
818  	if ((nm_ptr->map[w] & mask) != 0) {
819  		nm_ptr->map[w] &= ~mask;
820  		nm_ptr->count--;
821  	}
822  }
823  
824  /**
825   * tipc_nmap_diff - find differences between node maps
826   * @nm_a: input node map A
827   * @nm_b: input node map B
828   * @nm_diff: output node map A-B (i.e. nodes of A that are not in B)
829   */
830  static void tipc_nmap_diff(struct tipc_node_map *nm_a,
831  			   struct tipc_node_map *nm_b,
832  			   struct tipc_node_map *nm_diff)
833  {
834  	int stop = ARRAY_SIZE(nm_a->map);
835  	int w;
836  	int b;
837  	u32 map;
838  
839  	memset(nm_diff, 0, sizeof(*nm_diff));
840  	for (w = 0; w < stop; w++) {
841  		map = nm_a->map[w] ^ (nm_a->map[w] & nm_b->map[w]);
842  		nm_diff->map[w] = map;
843  		if (map != 0) {
844  			for (b = 0 ; b < WSIZE; b++) {
845  				if (map & (1 << b))
846  					nm_diff->count++;
847  			}
848  		}
849  	}
850  }
851  
852  /**
853   * tipc_port_list_add - add a port to a port list, ensuring no duplicates
854   */
855  void tipc_port_list_add(struct tipc_port_list *pl_ptr, u32 port)
856  {
857  	struct tipc_port_list *item = pl_ptr;
858  	int i;
859  	int item_sz = PLSIZE;
860  	int cnt = pl_ptr->count;
861  
862  	for (; ; cnt -= item_sz, item = item->next) {
863  		if (cnt < PLSIZE)
864  			item_sz = cnt;
865  		for (i = 0; i < item_sz; i++)
866  			if (item->ports[i] == port)
867  				return;
868  		if (i < PLSIZE) {
869  			item->ports[i] = port;
870  			pl_ptr->count++;
871  			return;
872  		}
873  		if (!item->next) {
874  			item->next = kmalloc(sizeof(*item), GFP_ATOMIC);
875  			if (!item->next) {
876  				pr_warn("Incomplete multicast delivery, no memory\n");
877  				return;
878  			}
879  			item->next->next = NULL;
880  		}
881  	}
882  }
883  
884  /**
885   * tipc_port_list_free - free dynamically created entries in port_list chain
886   *
887   */
888  void tipc_port_list_free(struct tipc_port_list *pl_ptr)
889  {
890  	struct tipc_port_list *item;
891  	struct tipc_port_list *next;
892  
893  	for (item = pl_ptr->next; item; item = next) {
894  		next = item->next;
895  		kfree(item);
896  	}
897  }
898