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v3.1
  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
 43#define MAX_PKT_DEFAULT_MCAST 1500	/* bcast link max packet size (fixed) */
 44
 45#define BCLINK_WIN_DEFAULT 20		/* bcast link window size (default) */
 46
 47/**
 48 * struct bcbearer_pair - a pair of bearers used by broadcast link
 49 * @primary: pointer to primary bearer
 50 * @secondary: pointer to secondary bearer
 51 *
 52 * Bearers must have same priority and same set of reachable destinations
 53 * to be paired.
 54 */
 55
 56struct bcbearer_pair {
 57	struct tipc_bearer *primary;
 58	struct tipc_bearer *secondary;
 59};
 60
 61/**
 62 * struct bcbearer - bearer used by broadcast link
 63 * @bearer: (non-standard) broadcast bearer structure
 64 * @media: (non-standard) broadcast media structure
 65 * @bpairs: array of bearer pairs
 66 * @bpairs_temp: temporary array of bearer pairs used by tipc_bcbearer_sort()
 67 * @remains: temporary node map used by tipc_bcbearer_send()
 68 * @remains_new: temporary node map used tipc_bcbearer_send()
 69 *
 70 * Note: The fields labelled "temporary" are incorporated into the bearer
 71 * to avoid consuming potentially limited stack space through the use of
 72 * large local variables within multicast routines.  Concurrent access is
 73 * prevented through use of the spinlock "bc_lock".
 74 */
 75
 76struct bcbearer {
 77	struct tipc_bearer bearer;
 78	struct media media;
 79	struct bcbearer_pair bpairs[MAX_BEARERS];
 80	struct 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 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 * @retransmit_to: node that most recently requested a retransmit
 90 *
 91 * Handles sequence numbering, fragmentation, bundling, etc.
 92 */
 93
 94struct bclink {
 95	struct link link;
 96	struct tipc_node node;
 
 97	struct tipc_node *retransmit_to;
 98};
 99
 
 
100
101static struct bcbearer *bcbearer;
102static struct bclink *bclink;
103static struct link *bcl;
104static DEFINE_SPINLOCK(bc_lock);
105
106/* broadcast-capable node map */
107struct tipc_node_map tipc_bcast_nmap;
108
109const char tipc_bclink_name[] = "broadcast-link";
110
111static void tipc_nmap_diff(struct tipc_node_map *nm_a,
112			   struct tipc_node_map *nm_b,
113			   struct tipc_node_map *nm_diff);
114
115static u32 buf_seqno(struct sk_buff *buf)
116{
117	return msg_seqno(buf_msg(buf));
118}
119
120static u32 bcbuf_acks(struct sk_buff *buf)
121{
122	return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
123}
124
125static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
126{
127	TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
128}
129
130static void bcbuf_decr_acks(struct sk_buff *buf)
131{
132	bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
133}
134
 
 
 
 
 
 
 
 
 
 
 
 
 
135
136static void bclink_set_last_sent(void)
137{
138	if (bcl->next_out)
139		bcl->fsm_msg_cnt = mod(buf_seqno(bcl->next_out) - 1);
140	else
141		bcl->fsm_msg_cnt = mod(bcl->next_out_no - 1);
142}
143
144u32 tipc_bclink_get_last_sent(void)
145{
146	return bcl->fsm_msg_cnt;
147}
148
149/**
150 * bclink_set_gap - set gap according to contents of current deferred pkt queue
151 *
152 * Called with 'node' locked, bc_lock unlocked
153 */
154
155static void bclink_set_gap(struct tipc_node *n_ptr)
156{
157	struct sk_buff *buf = n_ptr->bclink.deferred_head;
158
159	n_ptr->bclink.gap_after = n_ptr->bclink.gap_to =
160		mod(n_ptr->bclink.last_in);
161	if (unlikely(buf != NULL))
162		n_ptr->bclink.gap_to = mod(buf_seqno(buf) - 1);
163}
164
165/**
166 * bclink_ack_allowed - test if ACK or NACK message can be sent at this moment
167 *
168 * This mechanism endeavours to prevent all nodes in network from trying
169 * to ACK or NACK at the same time.
170 *
171 * Note: TIPC uses a different trigger to distribute ACKs than it does to
172 *       distribute NACKs, but tries to use the same spacing (divide by 16).
173 */
174
175static int bclink_ack_allowed(u32 n)
176{
177	return (n % TIPC_MIN_LINK_WIN) == tipc_own_tag;
178}
179
180
181/**
182 * tipc_bclink_retransmit_to - get most recent node to request retransmission
183 *
184 * Called with bc_lock locked
185 */
186
187struct tipc_node *tipc_bclink_retransmit_to(void)
188{
189	return bclink->retransmit_to;
190}
191
192/**
193 * bclink_retransmit_pkt - retransmit broadcast packets
194 * @after: sequence number of last packet to *not* retransmit
195 * @to: sequence number of last packet to retransmit
196 *
197 * Called with bc_lock locked
198 */
199
200static void bclink_retransmit_pkt(u32 after, u32 to)
201{
202	struct sk_buff *buf;
203
204	buf = bcl->first_out;
205	while (buf && less_eq(buf_seqno(buf), after))
206		buf = buf->next;
207	tipc_link_retransmit(bcl, buf, mod(to - after));
208}
209
210/**
211 * tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
212 * @n_ptr: node that sent acknowledgement info
213 * @acked: broadcast sequence # that has been acknowledged
214 *
215 * Node is locked, bc_lock unlocked.
216 */
217
218void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
219{
220	struct sk_buff *crs;
221	struct sk_buff *next;
222	unsigned int released = 0;
223
224	if (less_eq(acked, n_ptr->bclink.acked))
225		return;
226
227	spin_lock_bh(&bc_lock);
228
229	/* Skip over packets that node has previously acknowledged */
230
231	crs = bcl->first_out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
232	while (crs && less_eq(buf_seqno(crs), n_ptr->bclink.acked))
233		crs = crs->next;
234
235	/* Update packets that node is now acknowledging */
236
237	while (crs && less_eq(buf_seqno(crs), acked)) {
238		next = crs->next;
239		bcbuf_decr_acks(crs);
 
 
 
 
 
 
 
 
240		if (bcbuf_acks(crs) == 0) {
241			bcl->first_out = next;
242			bcl->out_queue_size--;
243			buf_discard(crs);
244			released = 1;
245		}
246		crs = next;
247	}
248	n_ptr->bclink.acked = acked;
249
250	/* Try resolving broadcast link congestion, if necessary */
251
252	if (unlikely(bcl->next_out)) {
253		tipc_link_push_queue(bcl);
254		bclink_set_last_sent();
255	}
256	if (unlikely(released && !list_empty(&bcl->waiting_ports)))
257		tipc_link_wakeup_ports(bcl, 0);
 
258	spin_unlock_bh(&bc_lock);
259}
260
261/**
262 * bclink_send_ack - unicast an ACK msg
263 *
264 * tipc_net_lock and node lock set
265 */
266
267static void bclink_send_ack(struct tipc_node *n_ptr)
268{
269	struct link *l_ptr = n_ptr->active_links[n_ptr->addr & 1];
270
271	if (l_ptr != NULL)
272		tipc_link_send_proto_msg(l_ptr, STATE_MSG, 0, 0, 0, 0, 0);
273}
274
275/**
276 * bclink_send_nack- broadcast a NACK msg
277 *
278 * tipc_net_lock and node lock set
279 */
280
281static void bclink_send_nack(struct tipc_node *n_ptr)
282{
283	struct sk_buff *buf;
284	struct tipc_msg *msg;
285
286	if (!less(n_ptr->bclink.gap_after, n_ptr->bclink.gap_to))
 
 
287		return;
288
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
289	buf = tipc_buf_acquire(INT_H_SIZE);
290	if (buf) {
291		msg = buf_msg(buf);
 
292		tipc_msg_init(msg, BCAST_PROTOCOL, STATE_MSG,
293			 INT_H_SIZE, n_ptr->addr);
294		msg_set_non_seq(msg, 1);
295		msg_set_mc_netid(msg, tipc_net_id);
296		msg_set_bcast_ack(msg, mod(n_ptr->bclink.last_in));
297		msg_set_bcgap_after(msg, n_ptr->bclink.gap_after);
298		msg_set_bcgap_to(msg, n_ptr->bclink.gap_to);
299		msg_set_bcast_tag(msg, tipc_own_tag);
300
301		if (tipc_bearer_send(&bcbearer->bearer, buf, NULL)) {
302			bcl->stats.sent_nacks++;
303			buf_discard(buf);
304		} else {
305			tipc_bearer_schedule(bcl->b_ptr, bcl);
306			bcl->proto_msg_queue = buf;
307			bcl->stats.bearer_congs++;
308		}
309
310		/*
311		 * Ensure we doesn't send another NACK msg to the node
312		 * until 16 more deferred messages arrive from it
313		 * (i.e. helps prevent all nodes from NACK'ing at same time)
314		 */
315
316		n_ptr->bclink.nack_sync = tipc_own_tag;
317	}
318}
319
320/**
321 * tipc_bclink_check_gap - send a NACK if a sequence gap exists
322 *
323 * tipc_net_lock and node lock set
324 */
325
326void tipc_bclink_check_gap(struct tipc_node *n_ptr, u32 last_sent)
327{
328	if (!n_ptr->bclink.supported ||
329	    less_eq(last_sent, mod(n_ptr->bclink.last_in)))
330		return;
331
332	bclink_set_gap(n_ptr);
333	if (n_ptr->bclink.gap_after == n_ptr->bclink.gap_to)
334		n_ptr->bclink.gap_to = last_sent;
335	bclink_send_nack(n_ptr);
336}
337
338/**
339 * tipc_bclink_peek_nack - process a NACK msg meant for another node
340 *
341 * Only tipc_net_lock set.
342 */
343
344static void tipc_bclink_peek_nack(u32 dest, u32 sender_tag, u32 gap_after, u32 gap_to)
345{
346	struct tipc_node *n_ptr = tipc_node_find(dest);
347	u32 my_after, my_to;
348
349	if (unlikely(!n_ptr || !tipc_node_is_up(n_ptr)))
350		return;
351	tipc_node_lock(n_ptr);
352	/*
353	 * Modify gap to suppress unnecessary NACKs from this node
354	 */
355	my_after = n_ptr->bclink.gap_after;
356	my_to = n_ptr->bclink.gap_to;
357
358	if (less_eq(gap_after, my_after)) {
359		if (less(my_after, gap_to) && less(gap_to, my_to))
360			n_ptr->bclink.gap_after = gap_to;
361		else if (less_eq(my_to, gap_to))
362			n_ptr->bclink.gap_to = n_ptr->bclink.gap_after;
363	} else if (less_eq(gap_after, my_to)) {
364		if (less_eq(my_to, gap_to))
365			n_ptr->bclink.gap_to = gap_after;
366	} else {
367		/*
368		 * Expand gap if missing bufs not in deferred queue:
369		 */
370		struct sk_buff *buf = n_ptr->bclink.deferred_head;
371		u32 prev = n_ptr->bclink.gap_to;
372
373		for (; buf; buf = buf->next) {
374			u32 seqno = buf_seqno(buf);
 
 
375
376			if (mod(seqno - prev) != 1) {
377				buf = NULL;
378				break;
379			}
380			if (seqno == gap_after)
381				break;
382			prev = seqno;
383		}
384		if (buf == NULL)
385			n_ptr->bclink.gap_to = gap_after;
386	}
387	/*
388	 * Some nodes may send a complementary NACK now:
389	 */
390	if (bclink_ack_allowed(sender_tag + 1)) {
391		if (n_ptr->bclink.gap_to != n_ptr->bclink.gap_after) {
392			bclink_send_nack(n_ptr);
393			bclink_set_gap(n_ptr);
394		}
395	}
396	tipc_node_unlock(n_ptr);
397}
398
399/**
400 * tipc_bclink_send_msg - broadcast a packet to all nodes in cluster
401 */
402
403int tipc_bclink_send_msg(struct sk_buff *buf)
404{
405	int res;
406
407	spin_lock_bh(&bc_lock);
408
409	res = tipc_link_send_buf(bcl, buf);
410	if (likely(res > 0))
411		bclink_set_last_sent();
412
413	bcl->stats.queue_sz_counts++;
414	bcl->stats.accu_queue_sz += bcl->out_queue_size;
415
 
 
 
 
 
 
 
416	spin_unlock_bh(&bc_lock);
417	return res;
418}
419
420/**
421 * tipc_bclink_recv_pkt - receive a broadcast packet, and deliver upwards
422 *
423 * tipc_net_lock is read_locked, no other locks set
424 */
 
 
 
 
 
 
 
 
 
 
 
425
426void tipc_bclink_recv_pkt(struct sk_buff *buf)
 
 
 
 
 
 
 
 
 
 
 
 
427{
428	struct tipc_msg *msg = buf_msg(buf);
429	struct tipc_node *node = tipc_node_find(msg_prevnode(msg));
430	u32 next_in;
431	u32 seqno;
432	struct sk_buff *deferred;
433
434	if (unlikely(!node || !tipc_node_is_up(node) || !node->bclink.supported ||
435		     (msg_mc_netid(msg) != tipc_net_id))) {
436		buf_discard(buf);
437		return;
438	}
 
 
 
 
 
 
 
 
 
439
440	if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) {
 
 
441		if (msg_destnode(msg) == tipc_own_addr) {
442			tipc_node_lock(node);
443			tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
444			tipc_node_unlock(node);
445			spin_lock_bh(&bc_lock);
446			bcl->stats.recv_nacks++;
447			bclink->retransmit_to = node;
448			bclink_retransmit_pkt(msg_bcgap_after(msg),
449					      msg_bcgap_to(msg));
450			spin_unlock_bh(&bc_lock);
451		} else {
452			tipc_bclink_peek_nack(msg_destnode(msg),
453					      msg_bcast_tag(msg),
454					      msg_bcgap_after(msg),
455					      msg_bcgap_to(msg));
456		}
457		buf_discard(buf);
458		return;
459	}
460
461	tipc_node_lock(node);
462receive:
463	deferred = node->bclink.deferred_head;
464	next_in = mod(node->bclink.last_in + 1);
465	seqno = msg_seqno(msg);
 
466
467	if (likely(seqno == next_in)) {
468		bcl->stats.recv_info++;
469		node->bclink.last_in++;
470		bclink_set_gap(node);
471		if (unlikely(bclink_ack_allowed(seqno))) {
472			bclink_send_ack(node);
473			bcl->stats.sent_acks++;
474		}
475		if (likely(msg_isdata(msg))) {
 
 
 
476			tipc_node_unlock(node);
477			tipc_port_recv_mcast(buf, NULL);
 
 
 
478		} else if (msg_user(msg) == MSG_BUNDLER) {
 
 
479			bcl->stats.recv_bundles++;
480			bcl->stats.recv_bundled += msg_msgcnt(msg);
 
481			tipc_node_unlock(node);
482			tipc_link_recv_bundle(buf);
483		} else if (msg_user(msg) == MSG_FRAGMENTER) {
 
 
 
 
 
 
 
 
484			bcl->stats.recv_fragments++;
485			if (tipc_link_recv_fragment(&node->bclink.defragm,
486						    &buf, &msg))
487				bcl->stats.recv_fragmented++;
 
 
 
 
 
 
 
 
 
 
 
488			tipc_node_unlock(node);
489			tipc_net_route_msg(buf);
490		} else {
 
 
 
491			tipc_node_unlock(node);
492			tipc_net_route_msg(buf);
493		}
494		if (deferred && (buf_seqno(deferred) == mod(next_in + 1))) {
495			tipc_node_lock(node);
496			buf = deferred;
497			msg = buf_msg(buf);
498			node->bclink.deferred_head = deferred->next;
499			goto receive;
500		}
501		return;
502	} else if (less(next_in, seqno)) {
503		u32 gap_after = node->bclink.gap_after;
504		u32 gap_to = node->bclink.gap_to;
505
506		if (tipc_link_defer_pkt(&node->bclink.deferred_head,
507					&node->bclink.deferred_tail,
508					buf)) {
509			node->bclink.nack_sync++;
510			bcl->stats.deferred_recv++;
511			if (seqno == mod(gap_after + 1))
512				node->bclink.gap_after = seqno;
513			else if (less(gap_after, seqno) && less(seqno, gap_to))
514				node->bclink.gap_to = seqno;
515		}
516		if (bclink_ack_allowed(node->bclink.nack_sync)) {
517			if (gap_to != gap_after)
518				bclink_send_nack(node);
519			bclink_set_gap(node);
520		}
521	} else {
522		bcl->stats.duplicates++;
523		buf_discard(buf);
 
 
 
 
 
 
 
 
 
 
524	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
525	tipc_node_unlock(node);
 
 
526}
527
528u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
529{
530	return (n_ptr->bclink.supported &&
531		(tipc_bclink_get_last_sent() != n_ptr->bclink.acked));
532}
533
534
535/**
536 * tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
537 *
538 * Send through as many bearers as necessary to reach all nodes
539 * that support TIPC multicasting.
540 *
541 * Returns 0 if packet sent successfully, non-zero if not
 
542 */
543
544static int tipc_bcbearer_send(struct sk_buff *buf,
545			      struct tipc_bearer *unused1,
546			      struct tipc_media_addr *unused2)
547{
548	int bp_index;
549
550	/* Prepare buffer for broadcasting (if first time trying to send it) */
551
 
 
 
552	if (likely(!msg_non_seq(buf_msg(buf)))) {
553		struct tipc_msg *msg;
554
555		bcbuf_set_acks(buf, tipc_bcast_nmap.count);
556		msg = buf_msg(buf);
557		msg_set_non_seq(msg, 1);
558		msg_set_mc_netid(msg, tipc_net_id);
559		bcl->stats.sent_info++;
560
561		if (WARN_ON(!tipc_bcast_nmap.count)) {
562			dump_stack();
563			return 0;
564		}
565	}
566
567	/* Send buffer over bearers until all targets reached */
568
569	bcbearer->remains = tipc_bcast_nmap;
570
571	for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
572		struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
573		struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
 
 
574
575		if (!p)
576			break;	/* no more bearers to try */
577
578		tipc_nmap_diff(&bcbearer->remains, &p->nodes, &bcbearer->remains_new);
 
579		if (bcbearer->remains_new.count == bcbearer->remains.count)
580			continue;	/* bearer pair doesn't add anything */
581
582		if (p->blocked ||
583		    p->media->send_msg(buf, p, &p->media->bcast_addr)) {
584			/* unable to send on primary bearer */
585			if (!s || s->blocked ||
586			    s->media->send_msg(buf, s,
587					       &s->media->bcast_addr)) {
588				/* unable to send on either bearer */
589				continue;
590			}
 
591		}
592
 
593		if (s) {
594			bcbearer->bpairs[bp_index].primary = s;
595			bcbearer->bpairs[bp_index].secondary = p;
596		}
597
598		if (bcbearer->remains_new.count == 0)
599			return 0;
600
601		bcbearer->remains = bcbearer->remains_new;
602	}
603
604	/*
605	 * Unable to reach all targets (indicate success, since currently
606	 * there isn't code in place to properly block & unblock the
607	 * pseudo-bearer used by the broadcast link)
608	 */
609
610	return TIPC_OK;
611}
612
613/**
614 * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
615 */
616
617void tipc_bcbearer_sort(void)
618{
619	struct bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
620	struct bcbearer_pair *bp_curr;
621	int b_index;
622	int pri;
623
624	spin_lock_bh(&bc_lock);
625
626	/* Group bearers by priority (can assume max of two per priority) */
627
628	memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
629
630	for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
631		struct tipc_bearer *b = &tipc_bearers[b_index];
632
633		if (!b->active || !b->nodes.count)
634			continue;
635
636		if (!bp_temp[b->priority].primary)
637			bp_temp[b->priority].primary = b;
638		else
639			bp_temp[b->priority].secondary = b;
640	}
641
642	/* Create array of bearer pairs for broadcasting */
643
644	bp_curr = bcbearer->bpairs;
645	memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
646
647	for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
648
649		if (!bp_temp[pri].primary)
650			continue;
651
652		bp_curr->primary = bp_temp[pri].primary;
653
654		if (bp_temp[pri].secondary) {
655			if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
656					    &bp_temp[pri].secondary->nodes)) {
657				bp_curr->secondary = bp_temp[pri].secondary;
658			} else {
659				bp_curr++;
660				bp_curr->primary = bp_temp[pri].secondary;
661			}
662		}
663
664		bp_curr++;
665	}
666
667	spin_unlock_bh(&bc_lock);
668}
669
670/**
671 * tipc_bcbearer_push - resolve bearer congestion
672 *
673 * Forces bclink to push out any unsent packets, until all packets are gone
674 * or congestion reoccurs.
675 * No locks set when function called
676 */
677
678void tipc_bcbearer_push(void)
679{
680	struct tipc_bearer *b_ptr;
681
682	spin_lock_bh(&bc_lock);
683	b_ptr = &bcbearer->bearer;
684	if (b_ptr->blocked) {
685		b_ptr->blocked = 0;
686		tipc_bearer_lock_push(b_ptr);
687	}
688	spin_unlock_bh(&bc_lock);
689}
690
691
692int tipc_bclink_stats(char *buf, const u32 buf_size)
693{
694	struct print_buf pb;
 
695
696	if (!bcl)
697		return 0;
698
699	tipc_printbuf_init(&pb, buf, buf_size);
700
701	spin_lock_bh(&bc_lock);
702
703	tipc_printf(&pb, "Link <%s>\n"
704			 "  Window:%u packets\n",
705		    bcl->name, bcl->queue_limit[0]);
706	tipc_printf(&pb, "  RX packets:%u fragments:%u/%u bundles:%u/%u\n",
707		    bcl->stats.recv_info,
708		    bcl->stats.recv_fragments,
709		    bcl->stats.recv_fragmented,
710		    bcl->stats.recv_bundles,
711		    bcl->stats.recv_bundled);
712	tipc_printf(&pb, "  TX packets:%u fragments:%u/%u bundles:%u/%u\n",
713		    bcl->stats.sent_info,
714		    bcl->stats.sent_fragments,
715		    bcl->stats.sent_fragmented,
716		    bcl->stats.sent_bundles,
717		    bcl->stats.sent_bundled);
718	tipc_printf(&pb, "  RX naks:%u defs:%u dups:%u\n",
719		    bcl->stats.recv_nacks,
720		    bcl->stats.deferred_recv,
721		    bcl->stats.duplicates);
722	tipc_printf(&pb, "  TX naks:%u acks:%u dups:%u\n",
723		    bcl->stats.sent_nacks,
724		    bcl->stats.sent_acks,
725		    bcl->stats.retransmitted);
726	tipc_printf(&pb, "  Congestion bearer:%u link:%u  Send queue max:%u avg:%u\n",
727		    bcl->stats.bearer_congs,
728		    bcl->stats.link_congs,
729		    bcl->stats.max_queue_sz,
730		    bcl->stats.queue_sz_counts
731		    ? (bcl->stats.accu_queue_sz / bcl->stats.queue_sz_counts)
732		    : 0);
733
734	spin_unlock_bh(&bc_lock);
735	return tipc_printbuf_validate(&pb);
736}
737
738int tipc_bclink_reset_stats(void)
739{
740	if (!bcl)
741		return -ENOPROTOOPT;
742
743	spin_lock_bh(&bc_lock);
744	memset(&bcl->stats, 0, sizeof(bcl->stats));
745	spin_unlock_bh(&bc_lock);
746	return 0;
747}
748
749int tipc_bclink_set_queue_limits(u32 limit)
750{
751	if (!bcl)
752		return -ENOPROTOOPT;
753	if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
754		return -EINVAL;
755
756	spin_lock_bh(&bc_lock);
757	tipc_link_set_queue_limits(bcl, limit);
758	spin_unlock_bh(&bc_lock);
759	return 0;
760}
761
762int tipc_bclink_init(void)
763{
764	bcbearer = kzalloc(sizeof(*bcbearer), GFP_ATOMIC);
765	bclink = kzalloc(sizeof(*bclink), GFP_ATOMIC);
766	if (!bcbearer || !bclink) {
767		warn("Multicast link creation failed, no memory\n");
768		kfree(bcbearer);
769		bcbearer = NULL;
770		kfree(bclink);
771		bclink = NULL;
772		return -ENOMEM;
773	}
774
775	INIT_LIST_HEAD(&bcbearer->bearer.cong_links);
776	bcbearer->bearer.media = &bcbearer->media;
777	bcbearer->media.send_msg = tipc_bcbearer_send;
778	sprintf(bcbearer->media.name, "tipc-multicast");
779
780	bcl = &bclink->link;
781	INIT_LIST_HEAD(&bcl->waiting_ports);
782	bcl->next_out_no = 1;
783	spin_lock_init(&bclink->node.lock);
784	bcl->owner = &bclink->node;
785	bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
786	tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
787	bcl->b_ptr = &bcbearer->bearer;
 
788	bcl->state = WORKING_WORKING;
789	strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
790
791	return 0;
792}
793
794void tipc_bclink_stop(void)
795{
796	spin_lock_bh(&bc_lock);
797	if (bcbearer) {
798		tipc_link_stop(bcl);
799		bcl = NULL;
800		kfree(bclink);
801		bclink = NULL;
802		kfree(bcbearer);
803		bcbearer = NULL;
804	}
805	spin_unlock_bh(&bc_lock);
 
 
 
 
806}
807
808
809/**
810 * tipc_nmap_add - add a node to a node map
811 */
812
813void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node)
814{
815	int n = tipc_node(node);
816	int w = n / WSIZE;
817	u32 mask = (1 << (n % WSIZE));
818
819	if ((nm_ptr->map[w] & mask) == 0) {
820		nm_ptr->count++;
821		nm_ptr->map[w] |= mask;
822	}
823}
824
825/**
826 * tipc_nmap_remove - remove a node from a node map
827 */
828
829void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node)
830{
831	int n = tipc_node(node);
832	int w = n / WSIZE;
833	u32 mask = (1 << (n % WSIZE));
834
835	if ((nm_ptr->map[w] & mask) != 0) {
836		nm_ptr->map[w] &= ~mask;
837		nm_ptr->count--;
838	}
839}
840
841/**
842 * tipc_nmap_diff - find differences between node maps
843 * @nm_a: input node map A
844 * @nm_b: input node map B
845 * @nm_diff: output node map A-B (i.e. nodes of A that are not in B)
846 */
847
848static void tipc_nmap_diff(struct tipc_node_map *nm_a,
849			   struct tipc_node_map *nm_b,
850			   struct tipc_node_map *nm_diff)
851{
852	int stop = ARRAY_SIZE(nm_a->map);
853	int w;
854	int b;
855	u32 map;
856
857	memset(nm_diff, 0, sizeof(*nm_diff));
858	for (w = 0; w < stop; w++) {
859		map = nm_a->map[w] ^ (nm_a->map[w] & nm_b->map[w]);
860		nm_diff->map[w] = map;
861		if (map != 0) {
862			for (b = 0 ; b < WSIZE; b++) {
863				if (map & (1 << b))
864					nm_diff->count++;
865			}
866		}
867	}
868}
869
870/**
871 * tipc_port_list_add - add a port to a port list, ensuring no duplicates
872 */
873
874void tipc_port_list_add(struct port_list *pl_ptr, u32 port)
875{
876	struct port_list *item = pl_ptr;
877	int i;
878	int item_sz = PLSIZE;
879	int cnt = pl_ptr->count;
880
881	for (; ; cnt -= item_sz, item = item->next) {
882		if (cnt < PLSIZE)
883			item_sz = cnt;
884		for (i = 0; i < item_sz; i++)
885			if (item->ports[i] == port)
886				return;
887		if (i < PLSIZE) {
888			item->ports[i] = port;
889			pl_ptr->count++;
890			return;
891		}
892		if (!item->next) {
893			item->next = kmalloc(sizeof(*item), GFP_ATOMIC);
894			if (!item->next) {
895				warn("Incomplete multicast delivery, no memory\n");
896				return;
897			}
898			item->next->next = NULL;
899		}
900	}
901}
902
903/**
904 * tipc_port_list_free - free dynamically created entries in port_list chain
905 *
906 */
907
908void tipc_port_list_free(struct port_list *pl_ptr)
909{
910	struct port_list *item;
911	struct port_list *next;
912
913	for (item = pl_ptr->next; item; item = next) {
914		next = item->next;
915		kfree(item);
916	}
917}
918
v3.15
  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#define	BCLINK_WIN_DEFAULT	20	/* bcast link window size (default) */
 46#define	BCBEARER		MAX_BEARERS
 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
 57struct 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 */
 76struct 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 */
 94struct 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
101static struct tipc_bcbearer bcast_bearer;
102static struct tipc_bclink bcast_link;
103
104static struct tipc_bcbearer *bcbearer = &bcast_bearer;
105static struct tipc_bclink *bclink = &bcast_link;
106static struct tipc_link *bcl = &bcast_link.link;
 
107
108static DEFINE_SPINLOCK(bc_lock);
 
109
110const char tipc_bclink_name[] = "broadcast-link";
111
112static 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
 
 
 
 
 
116static u32 bcbuf_acks(struct sk_buff *buf)
117{
118	return (u32)(unsigned long)TIPC_SKB_CB(buf)->handle;
119}
120
121static void bcbuf_set_acks(struct sk_buff *buf, u32 acks)
122{
123	TIPC_SKB_CB(buf)->handle = (void *)(unsigned long)acks;
124}
125
126static void bcbuf_decr_acks(struct sk_buff *buf)
127{
128	bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
129}
130
131void 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
138void 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
145static 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
153u32 tipc_bclink_get_last_sent(void)
154{
155	return bcl->fsm_msg_cnt;
156}
157
158static 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 */
 
170struct 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 */
 
182static 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 */
 
199void 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);
269exit:
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 */
278void 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 */
341static 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_xmit - broadcast a packet to all nodes in cluster
360 */
361int tipc_bclink_xmit(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_xmit(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	}
379exit:
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 */
389static 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_proto_xmit(node->active_links[node->addr & 1],
403				     STATE_MSG, 0, 0, 0, 0, 0);
404		bcl->stats.sent_acks++;
405	}
406}
407
408/**
409 * tipc_bclink_rcv - receive a broadcast packet, and deliver upwards
410 *
411 * tipc_net_lock is read_locked, no other locks set
412 */
413void tipc_bclink_rcv(struct sk_buff *buf)
414{
415	struct tipc_msg *msg = buf_msg(buf);
416	struct tipc_node *node;
417	u32 next_in;
418	u32 seqno;
419	int deferred;
420
421	/* Screen out unwanted broadcast messages */
422
423	if (msg_mc_netid(msg) != tipc_net_id)
424		goto exit;
425
426	node = tipc_node_find(msg_prevnode(msg));
427	if (unlikely(!node))
428		goto exit;
429
430	tipc_node_lock(node);
431	if (unlikely(!node->bclink.recv_permitted))
432		goto unlock;
433
434	/* Handle broadcast protocol message */
435
436	if (unlikely(msg_user(msg) == BCAST_PROTOCOL)) {
437		if (msg_type(msg) != STATE_MSG)
438			goto unlock;
439		if (msg_destnode(msg) == tipc_own_addr) {
 
440			tipc_bclink_acknowledge(node, msg_bcast_ack(msg));
441			tipc_node_unlock(node);
442			spin_lock_bh(&bc_lock);
443			bcl->stats.recv_nacks++;
444			bclink->retransmit_to = node;
445			bclink_retransmit_pkt(msg_bcgap_after(msg),
446					      msg_bcgap_to(msg));
447			spin_unlock_bh(&bc_lock);
448		} else {
449			tipc_node_unlock(node);
450			bclink_peek_nack(msg);
 
 
451		}
452		goto exit;
 
453	}
454
455	/* Handle in-sequence broadcast message */
456
 
 
457	seqno = msg_seqno(msg);
458	next_in = mod(node->bclink.last_in + 1);
459
460	if (likely(seqno == next_in)) {
461receive:
462		/* Deliver message to destination */
463
 
 
 
 
464		if (likely(msg_isdata(msg))) {
465			spin_lock_bh(&bc_lock);
466			bclink_accept_pkt(node, seqno);
467			spin_unlock_bh(&bc_lock);
468			tipc_node_unlock(node);
469			if (likely(msg_mcast(msg)))
470				tipc_port_mcast_rcv(buf, NULL);
471			else
472				kfree_skb(buf);
473		} else if (msg_user(msg) == MSG_BUNDLER) {
474			spin_lock_bh(&bc_lock);
475			bclink_accept_pkt(node, seqno);
476			bcl->stats.recv_bundles++;
477			bcl->stats.recv_bundled += msg_msgcnt(msg);
478			spin_unlock_bh(&bc_lock);
479			tipc_node_unlock(node);
480			tipc_link_bundle_rcv(buf);
481		} else if (msg_user(msg) == MSG_FRAGMENTER) {
482			int ret;
483			ret = tipc_link_frag_rcv(&node->bclink.reasm_head,
484						 &node->bclink.reasm_tail,
485						 &buf);
486			if (ret == LINK_REASM_ERROR)
487				goto unlock;
488			spin_lock_bh(&bc_lock);
489			bclink_accept_pkt(node, seqno);
490			bcl->stats.recv_fragments++;
491			if (ret == LINK_REASM_COMPLETE) {
 
492				bcl->stats.recv_fragmented++;
493				/* Point msg to inner header */
494				msg = buf_msg(buf);
495				spin_unlock_bh(&bc_lock);
496				goto receive;
497			}
498			spin_unlock_bh(&bc_lock);
499			tipc_node_unlock(node);
500		} else if (msg_user(msg) == NAME_DISTRIBUTOR) {
501			spin_lock_bh(&bc_lock);
502			bclink_accept_pkt(node, seqno);
503			spin_unlock_bh(&bc_lock);
504			tipc_node_unlock(node);
505			tipc_named_rcv(buf);
506		} else {
507			spin_lock_bh(&bc_lock);
508			bclink_accept_pkt(node, seqno);
509			spin_unlock_bh(&bc_lock);
510			tipc_node_unlock(node);
511			kfree_skb(buf);
512		}
513		buf = NULL;
514
515		/* Determine new synchronization state */
516
517		tipc_node_lock(node);
518		if (unlikely(!tipc_node_is_up(node)))
519			goto unlock;
520
521		if (node->bclink.last_in == node->bclink.last_sent)
522			goto unlock;
523
524		if (!node->bclink.deferred_head) {
525			node->bclink.oos_state = 1;
526			goto unlock;
 
 
 
 
 
 
 
 
 
 
 
 
527		}
528
529		msg = buf_msg(node->bclink.deferred_head);
530		seqno = msg_seqno(msg);
531		next_in = mod(next_in + 1);
532		if (seqno != next_in)
533			goto unlock;
534
535		/* Take in-sequence message from deferred queue & deliver it */
536
537		buf = node->bclink.deferred_head;
538		node->bclink.deferred_head = buf->next;
539		node->bclink.deferred_size--;
540		goto receive;
541	}
542
543	/* Handle out-of-sequence broadcast message */
544
545	if (less(next_in, seqno)) {
546		deferred = tipc_link_defer_pkt(&node->bclink.deferred_head,
547					       &node->bclink.deferred_tail,
548					       buf);
549		node->bclink.deferred_size += deferred;
550		bclink_update_last_sent(node, seqno);
551		buf = NULL;
552	} else
553		deferred = 0;
554
555	spin_lock_bh(&bc_lock);
556
557	if (deferred)
558		bcl->stats.deferred_recv++;
559	else
560		bcl->stats.duplicates++;
561
562	spin_unlock_bh(&bc_lock);
563
564unlock:
565	tipc_node_unlock(node);
566exit:
567	kfree_skb(buf);
568}
569
570u32 tipc_bclink_acks_missing(struct tipc_node *n_ptr)
571{
572	return (n_ptr->bclink.recv_permitted &&
573		(tipc_bclink_get_last_sent() != n_ptr->bclink.acked));
574}
575
576
577/**
578 * tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
579 *
580 * Send packet over as many bearers as necessary to reach all nodes
581 * that have joined the broadcast link.
582 *
583 * Returns 0 (packet sent successfully) under all circumstances,
584 * since the broadcast link's pseudo-bearer never blocks
585 */
586static int tipc_bcbearer_send(struct sk_buff *buf, struct tipc_bearer *unused1,
 
 
587			      struct tipc_media_addr *unused2)
588{
589	int bp_index;
590
591	/* Prepare broadcast link message for reliable transmission,
592	 * if first time trying to send it;
593	 * preparation is skipped for broadcast link protocol messages
594	 * since they are sent in an unreliable manner and don't need it
595	 */
596	if (likely(!msg_non_seq(buf_msg(buf)))) {
597		struct tipc_msg *msg;
598
599		bcbuf_set_acks(buf, bclink->bcast_nodes.count);
600		msg = buf_msg(buf);
601		msg_set_non_seq(msg, 1);
602		msg_set_mc_netid(msg, tipc_net_id);
603		bcl->stats.sent_info++;
604
605		if (WARN_ON(!bclink->bcast_nodes.count)) {
606			dump_stack();
607			return 0;
608		}
609	}
610
611	/* Send buffer over bearers until all targets reached */
612	bcbearer->remains = bclink->bcast_nodes;
 
613
614	for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
615		struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
616		struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
617		struct tipc_bearer *b = p;
618		struct sk_buff *tbuf;
619
620		if (!p)
621			break; /* No more bearers to try */
622
623		tipc_nmap_diff(&bcbearer->remains, &b->nodes,
624			       &bcbearer->remains_new);
625		if (bcbearer->remains_new.count == bcbearer->remains.count)
626			continue; /* Nothing added by bearer pair */
627
628		if (bp_index == 0) {
629			/* Use original buffer for first bearer */
630			tipc_bearer_send(b, buf, &b->bcast_addr);
631		} else {
632			/* Avoid concurrent buffer access */
633			tbuf = pskb_copy(buf, GFP_ATOMIC);
634			if (!tbuf)
635				break;
636			tipc_bearer_send(b, tbuf, &b->bcast_addr);
637			kfree_skb(tbuf); /* Bearer keeps a clone */
638		}
639
640		/* Swap bearers for next packet */
641		if (s) {
642			bcbearer->bpairs[bp_index].primary = s;
643			bcbearer->bpairs[bp_index].secondary = p;
644		}
645
646		if (bcbearer->remains_new.count == 0)
647			break; /* All targets reached */
648
649		bcbearer->remains = bcbearer->remains_new;
650	}
651
652	return 0;
 
 
 
 
 
 
653}
654
655/**
656 * tipc_bcbearer_sort - create sets of bearer pairs used by broadcast bearer
657 */
 
658void tipc_bcbearer_sort(void)
659{
660	struct tipc_bcbearer_pair *bp_temp = bcbearer->bpairs_temp;
661	struct tipc_bcbearer_pair *bp_curr;
662	int b_index;
663	int pri;
664
665	spin_lock_bh(&bc_lock);
666
667	/* Group bearers by priority (can assume max of two per priority) */
 
668	memset(bp_temp, 0, sizeof(bcbearer->bpairs_temp));
669
670	for (b_index = 0; b_index < MAX_BEARERS; b_index++) {
671		struct tipc_bearer *b = bearer_list[b_index];
672		if (!b || !b->nodes.count)
 
673			continue;
674
675		if (!bp_temp[b->priority].primary)
676			bp_temp[b->priority].primary = b;
677		else
678			bp_temp[b->priority].secondary = b;
679	}
680
681	/* Create array of bearer pairs for broadcasting */
 
682	bp_curr = bcbearer->bpairs;
683	memset(bcbearer->bpairs, 0, sizeof(bcbearer->bpairs));
684
685	for (pri = TIPC_MAX_LINK_PRI; pri >= 0; pri--) {
686
687		if (!bp_temp[pri].primary)
688			continue;
689
690		bp_curr->primary = bp_temp[pri].primary;
691
692		if (bp_temp[pri].secondary) {
693			if (tipc_nmap_equal(&bp_temp[pri].primary->nodes,
694					    &bp_temp[pri].secondary->nodes)) {
695				bp_curr->secondary = bp_temp[pri].secondary;
696			} else {
697				bp_curr++;
698				bp_curr->primary = bp_temp[pri].secondary;
699			}
700		}
701
702		bp_curr++;
703	}
704
705	spin_unlock_bh(&bc_lock);
706}
707
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
708
709int tipc_bclink_stats(char *buf, const u32 buf_size)
710{
711	int ret;
712	struct tipc_stats *s;
713
714	if (!bcl)
715		return 0;
716
 
 
717	spin_lock_bh(&bc_lock);
718
719	s = &bcl->stats;
720
721	ret = tipc_snprintf(buf, buf_size, "Link <%s>\n"
722			    "  Window:%u packets\n",
723			    bcl->name, bcl->queue_limit[0]);
724	ret += tipc_snprintf(buf + ret, buf_size - ret,
725			     "  RX packets:%u fragments:%u/%u bundles:%u/%u\n",
726			     s->recv_info, s->recv_fragments,
727			     s->recv_fragmented, s->recv_bundles,
728			     s->recv_bundled);
729	ret += tipc_snprintf(buf + ret, buf_size - ret,
730			     "  TX packets:%u fragments:%u/%u bundles:%u/%u\n",
731			     s->sent_info, s->sent_fragments,
732			     s->sent_fragmented, s->sent_bundles,
733			     s->sent_bundled);
734	ret += tipc_snprintf(buf + ret, buf_size - ret,
735			     "  RX naks:%u defs:%u dups:%u\n",
736			     s->recv_nacks, s->deferred_recv, s->duplicates);
737	ret += tipc_snprintf(buf + ret, buf_size - ret,
738			     "  TX naks:%u acks:%u dups:%u\n",
739			     s->sent_nacks, s->sent_acks, s->retransmitted);
740	ret += tipc_snprintf(buf + ret, buf_size - ret,
741			     "  Congestion link:%u  Send queue max:%u avg:%u\n",
742			     s->link_congs, s->max_queue_sz,
743			     s->queue_sz_counts ?
744			     (s->accu_queue_sz / s->queue_sz_counts) : 0);
 
 
 
 
745
746	spin_unlock_bh(&bc_lock);
747	return ret;
748}
749
750int tipc_bclink_reset_stats(void)
751{
752	if (!bcl)
753		return -ENOPROTOOPT;
754
755	spin_lock_bh(&bc_lock);
756	memset(&bcl->stats, 0, sizeof(bcl->stats));
757	spin_unlock_bh(&bc_lock);
758	return 0;
759}
760
761int tipc_bclink_set_queue_limits(u32 limit)
762{
763	if (!bcl)
764		return -ENOPROTOOPT;
765	if ((limit < TIPC_MIN_LINK_WIN) || (limit > TIPC_MAX_LINK_WIN))
766		return -EINVAL;
767
768	spin_lock_bh(&bc_lock);
769	tipc_link_set_queue_limits(bcl, limit);
770	spin_unlock_bh(&bc_lock);
771	return 0;
772}
773
774void tipc_bclink_init(void)
775{
 
 
 
 
 
 
 
 
 
 
 
 
776	bcbearer->bearer.media = &bcbearer->media;
777	bcbearer->media.send_msg = tipc_bcbearer_send;
778	sprintf(bcbearer->media.name, "tipc-broadcast");
779
 
780	INIT_LIST_HEAD(&bcl->waiting_ports);
781	bcl->next_out_no = 1;
782	spin_lock_init(&bclink->node.lock);
783	bcl->owner = &bclink->node;
784	bcl->max_pkt = MAX_PKT_DEFAULT_MCAST;
785	tipc_link_set_queue_limits(bcl, BCLINK_WIN_DEFAULT);
786	bcl->b_ptr = &bcbearer->bearer;
787	bearer_list[BCBEARER] = &bcbearer->bearer;
788	bcl->state = WORKING_WORKING;
789	strlcpy(bcl->name, tipc_bclink_name, TIPC_MAX_LINK_NAME);
 
 
790}
791
792void tipc_bclink_stop(void)
793{
794	spin_lock_bh(&bc_lock);
795	tipc_link_purge_queues(bcl);
 
 
 
 
 
 
 
796	spin_unlock_bh(&bc_lock);
797
798	bearer_list[BCBEARER] = NULL;
799	memset(bclink, 0, sizeof(*bclink));
800	memset(bcbearer, 0, sizeof(*bcbearer));
801}
802
803
804/**
805 * tipc_nmap_add - add a node to a node map
806 */
 
807void tipc_nmap_add(struct tipc_node_map *nm_ptr, u32 node)
808{
809	int n = tipc_node(node);
810	int w = n / WSIZE;
811	u32 mask = (1 << (n % WSIZE));
812
813	if ((nm_ptr->map[w] & mask) == 0) {
814		nm_ptr->count++;
815		nm_ptr->map[w] |= mask;
816	}
817}
818
819/**
820 * tipc_nmap_remove - remove a node from a node map
821 */
 
822void tipc_nmap_remove(struct tipc_node_map *nm_ptr, u32 node)
823{
824	int n = tipc_node(node);
825	int w = n / WSIZE;
826	u32 mask = (1 << (n % WSIZE));
827
828	if ((nm_ptr->map[w] & mask) != 0) {
829		nm_ptr->map[w] &= ~mask;
830		nm_ptr->count--;
831	}
832}
833
834/**
835 * tipc_nmap_diff - find differences between node maps
836 * @nm_a: input node map A
837 * @nm_b: input node map B
838 * @nm_diff: output node map A-B (i.e. nodes of A that are not in B)
839 */
 
840static void tipc_nmap_diff(struct tipc_node_map *nm_a,
841			   struct tipc_node_map *nm_b,
842			   struct tipc_node_map *nm_diff)
843{
844	int stop = ARRAY_SIZE(nm_a->map);
845	int w;
846	int b;
847	u32 map;
848
849	memset(nm_diff, 0, sizeof(*nm_diff));
850	for (w = 0; w < stop; w++) {
851		map = nm_a->map[w] ^ (nm_a->map[w] & nm_b->map[w]);
852		nm_diff->map[w] = map;
853		if (map != 0) {
854			for (b = 0 ; b < WSIZE; b++) {
855				if (map & (1 << b))
856					nm_diff->count++;
857			}
858		}
859	}
860}
861
862/**
863 * tipc_port_list_add - add a port to a port list, ensuring no duplicates
864 */
865void tipc_port_list_add(struct tipc_port_list *pl_ptr, u32 port)
 
866{
867	struct tipc_port_list *item = pl_ptr;
868	int i;
869	int item_sz = PLSIZE;
870	int cnt = pl_ptr->count;
871
872	for (; ; cnt -= item_sz, item = item->next) {
873		if (cnt < PLSIZE)
874			item_sz = cnt;
875		for (i = 0; i < item_sz; i++)
876			if (item->ports[i] == port)
877				return;
878		if (i < PLSIZE) {
879			item->ports[i] = port;
880			pl_ptr->count++;
881			return;
882		}
883		if (!item->next) {
884			item->next = kmalloc(sizeof(*item), GFP_ATOMIC);
885			if (!item->next) {
886				pr_warn("Incomplete multicast delivery, no memory\n");
887				return;
888			}
889			item->next->next = NULL;
890		}
891	}
892}
893
894/**
895 * tipc_port_list_free - free dynamically created entries in port_list chain
896 *
897 */
898void tipc_port_list_free(struct tipc_port_list *pl_ptr)
 
899{
900	struct tipc_port_list *item;
901	struct tipc_port_list *next;
902
903	for (item = pl_ptr->next; item; item = next) {
904		next = item->next;
905		kfree(item);
906	}
907}