2 * net/tipc/link.c: TIPC link code
4 * Copyright (c) 1996-2007, 2012-2015, Ericsson AB
5 * Copyright (c) 2004-2007, 2010-2013, Wind River Systems
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
42 #include "name_distr.h"
46 #include <linux/pkt_sched.h>
49 * Error message prefixes
51 static const char *link_co_err = "Link tunneling error, ";
52 static const char *link_rst_msg = "Resetting link ";
53 static const char tipc_bclink_name[] = "broadcast-link";
55 static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = {
56 [TIPC_NLA_LINK_UNSPEC] = { .type = NLA_UNSPEC },
57 [TIPC_NLA_LINK_NAME] = {
59 .len = TIPC_MAX_LINK_NAME
61 [TIPC_NLA_LINK_MTU] = { .type = NLA_U32 },
62 [TIPC_NLA_LINK_BROADCAST] = { .type = NLA_FLAG },
63 [TIPC_NLA_LINK_UP] = { .type = NLA_FLAG },
64 [TIPC_NLA_LINK_ACTIVE] = { .type = NLA_FLAG },
65 [TIPC_NLA_LINK_PROP] = { .type = NLA_NESTED },
66 [TIPC_NLA_LINK_STATS] = { .type = NLA_NESTED },
67 [TIPC_NLA_LINK_RX] = { .type = NLA_U32 },
68 [TIPC_NLA_LINK_TX] = { .type = NLA_U32 }
71 /* Properties valid for media, bearar and link */
72 static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = {
73 [TIPC_NLA_PROP_UNSPEC] = { .type = NLA_UNSPEC },
74 [TIPC_NLA_PROP_PRIO] = { .type = NLA_U32 },
75 [TIPC_NLA_PROP_TOL] = { .type = NLA_U32 },
76 [TIPC_NLA_PROP_WIN] = { .type = NLA_U32 }
80 * Interval between NACKs when packets arrive out of order
82 #define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
84 * Out-of-range value for link session numbers
86 #define WILDCARD_SESSION 0x10000
91 LINK_ESTABLISHED = 0xe,
92 LINK_ESTABLISHING = 0xe << 4,
93 LINK_RESET = 0x1 << 8,
94 LINK_RESETTING = 0x2 << 12,
95 LINK_PEER_RESET = 0xd << 16,
96 LINK_FAILINGOVER = 0xf << 20,
97 LINK_SYNCHING = 0xc << 24
100 /* Link FSM state checking routines
102 static int link_is_up(struct tipc_link *l)
104 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
107 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
108 struct sk_buff_head *xmitq);
109 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
110 u16 rcvgap, int tolerance, int priority,
111 struct sk_buff_head *xmitq);
112 static void link_reset_statistics(struct tipc_link *l_ptr);
113 static void link_print(struct tipc_link *l_ptr, const char *str);
114 static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf);
117 * Simple non-static link routines (i.e. referenced outside this file)
119 bool tipc_link_is_up(struct tipc_link *l)
121 return link_is_up(l);
124 bool tipc_link_peer_is_down(struct tipc_link *l)
126 return l->state == LINK_PEER_RESET;
129 bool tipc_link_is_reset(struct tipc_link *l)
131 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
134 bool tipc_link_is_establishing(struct tipc_link *l)
136 return l->state == LINK_ESTABLISHING;
139 bool tipc_link_is_synching(struct tipc_link *l)
141 return l->state == LINK_SYNCHING;
144 bool tipc_link_is_failingover(struct tipc_link *l)
146 return l->state == LINK_FAILINGOVER;
149 bool tipc_link_is_blocked(struct tipc_link *l)
151 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
154 int tipc_link_is_active(struct tipc_link *l)
156 struct tipc_node *n = l->owner;
158 return (node_active_link(n, 0) == l) || (node_active_link(n, 1) == l);
161 void tipc_link_add_bc_peer(struct tipc_link *l)
166 void tipc_link_remove_bc_peer(struct tipc_link *l)
171 int tipc_link_bc_peers(struct tipc_link *l)
176 static u32 link_own_addr(struct tipc_link *l)
178 return msg_prevnode(l->pmsg);
182 * tipc_link_create - create a new link
183 * @n: pointer to associated node
184 * @if_name: associated interface name
185 * @bearer_id: id (index) of associated bearer
186 * @tolerance: link tolerance to be used by link
187 * @net_plane: network plane (A,B,c..) this link belongs to
188 * @mtu: mtu to be advertised by link
189 * @priority: priority to be used by link
190 * @window: send window to be used by link
191 * @session: session to be used by link
192 * @ownnode: identity of own node
193 * @peer: node id of peer node
194 * @peer_caps: bitmap describing peer node capabilities
195 * @maddr: media address to be used
196 * @inputq: queue to put messages ready for delivery
197 * @namedq: queue to put binding table update messages ready for delivery
198 * @link: return value, pointer to put the created link
200 * Returns true if link was created, otherwise false
202 bool tipc_link_create(struct tipc_node *n, char *if_name, int bearer_id,
203 int tolerance, char net_plane, u32 mtu, int priority,
204 int window, u32 session, u32 ownnode, u32 peer,
205 u16 peer_caps, struct tipc_media_addr *maddr,
206 struct sk_buff_head *inputq, struct sk_buff_head *namedq,
207 struct tipc_link **link)
210 struct tipc_msg *hdr;
212 l = kzalloc(sizeof(*l), GFP_ATOMIC);
216 l->pmsg = (struct tipc_msg *)&l->proto_msg;
218 tipc_msg_init(ownnode, hdr, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, peer);
219 msg_set_size(hdr, sizeof(l->proto_msg));
220 msg_set_session(hdr, session);
221 msg_set_bearer_id(hdr, l->bearer_id);
223 /* Note: peer i/f name is completed by reset/activate message */
224 sprintf(l->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
225 tipc_zone(ownnode), tipc_cluster(ownnode), tipc_node(ownnode),
226 if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
227 strcpy((char *)msg_data(hdr), if_name);
230 l->peer_caps = peer_caps;
231 l->media_addr = maddr;
233 l->peer_session = WILDCARD_SESSION;
234 l->bearer_id = bearer_id;
235 l->tolerance = tolerance;
236 l->net_plane = net_plane;
237 l->advertised_mtu = mtu;
239 l->priority = priority;
240 tipc_link_set_queue_limits(l, window);
244 l->state = LINK_RESETTING;
245 __skb_queue_head_init(&l->transmq);
246 __skb_queue_head_init(&l->backlogq);
247 __skb_queue_head_init(&l->deferdq);
248 skb_queue_head_init(&l->wakeupq);
249 skb_queue_head_init(l->inputq);
254 * tipc_link_bc_create - create new link to be used for broadcast
255 * @n: pointer to associated node
256 * @mtu: mtu to be used
257 * @window: send window to be used
258 * @inputq: queue to put messages ready for delivery
259 * @namedq: queue to put binding table update messages ready for delivery
260 * @link: return value, pointer to put the created link
262 * Returns true if link was created, otherwise false
264 bool tipc_link_bc_create(struct tipc_node *n, int mtu, int window,
266 struct sk_buff_head *inputq,
267 struct sk_buff_head *namedq,
268 struct tipc_link **link)
272 if (!tipc_link_create(n, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
273 0, 0, 0, peer_caps, NULL, inputq, namedq, link))
277 strcpy(l->name, tipc_bclink_name);
283 /* tipc_link_build_bcast_sync_msg() - synchronize broadcast link endpoints.
285 * Give a newly added peer node the sequence number where it should
286 * start receiving and acking broadcast packets.
288 void tipc_link_build_bcast_sync_msg(struct tipc_link *l,
289 struct sk_buff_head *xmitq)
292 struct sk_buff_head list;
295 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
296 0, l->addr, link_own_addr(l), 0, 0, 0);
299 last_sent = tipc_bclink_get_last_sent(l->owner->net);
300 msg_set_last_bcast(buf_msg(skb), last_sent);
301 __skb_queue_head_init(&list);
302 __skb_queue_tail(&list, skb);
303 tipc_link_xmit(l, &list, xmitq);
307 * tipc_link_fsm_evt - link finite state machine
308 * @l: pointer to link
309 * @evt: state machine event to be processed
311 int tipc_link_fsm_evt(struct tipc_link *l, int evt)
318 case LINK_PEER_RESET_EVT:
319 l->state = LINK_PEER_RESET;
322 l->state = LINK_RESET;
324 case LINK_FAILURE_EVT:
325 case LINK_FAILOVER_BEGIN_EVT:
326 case LINK_ESTABLISH_EVT:
327 case LINK_FAILOVER_END_EVT:
328 case LINK_SYNCH_BEGIN_EVT:
329 case LINK_SYNCH_END_EVT:
336 case LINK_PEER_RESET_EVT:
337 l->state = LINK_ESTABLISHING;
339 case LINK_FAILOVER_BEGIN_EVT:
340 l->state = LINK_FAILINGOVER;
341 case LINK_FAILURE_EVT:
343 case LINK_ESTABLISH_EVT:
344 case LINK_FAILOVER_END_EVT:
346 case LINK_SYNCH_BEGIN_EVT:
347 case LINK_SYNCH_END_EVT:
352 case LINK_PEER_RESET:
355 l->state = LINK_ESTABLISHING;
357 case LINK_PEER_RESET_EVT:
358 case LINK_ESTABLISH_EVT:
359 case LINK_FAILURE_EVT:
361 case LINK_SYNCH_BEGIN_EVT:
362 case LINK_SYNCH_END_EVT:
363 case LINK_FAILOVER_BEGIN_EVT:
364 case LINK_FAILOVER_END_EVT:
369 case LINK_FAILINGOVER:
371 case LINK_FAILOVER_END_EVT:
372 l->state = LINK_RESET;
374 case LINK_PEER_RESET_EVT:
376 case LINK_ESTABLISH_EVT:
377 case LINK_FAILURE_EVT:
379 case LINK_FAILOVER_BEGIN_EVT:
380 case LINK_SYNCH_BEGIN_EVT:
381 case LINK_SYNCH_END_EVT:
386 case LINK_ESTABLISHING:
388 case LINK_ESTABLISH_EVT:
389 l->state = LINK_ESTABLISHED;
391 case LINK_FAILOVER_BEGIN_EVT:
392 l->state = LINK_FAILINGOVER;
395 l->state = LINK_RESET;
397 case LINK_FAILURE_EVT:
398 case LINK_PEER_RESET_EVT:
399 case LINK_SYNCH_BEGIN_EVT:
400 case LINK_FAILOVER_END_EVT:
402 case LINK_SYNCH_END_EVT:
407 case LINK_ESTABLISHED:
409 case LINK_PEER_RESET_EVT:
410 l->state = LINK_PEER_RESET;
411 rc |= TIPC_LINK_DOWN_EVT;
413 case LINK_FAILURE_EVT:
414 l->state = LINK_RESETTING;
415 rc |= TIPC_LINK_DOWN_EVT;
418 l->state = LINK_RESET;
420 case LINK_ESTABLISH_EVT:
421 case LINK_SYNCH_END_EVT:
423 case LINK_SYNCH_BEGIN_EVT:
424 l->state = LINK_SYNCHING;
426 case LINK_FAILOVER_BEGIN_EVT:
427 case LINK_FAILOVER_END_EVT:
434 case LINK_PEER_RESET_EVT:
435 l->state = LINK_PEER_RESET;
436 rc |= TIPC_LINK_DOWN_EVT;
438 case LINK_FAILURE_EVT:
439 l->state = LINK_RESETTING;
440 rc |= TIPC_LINK_DOWN_EVT;
443 l->state = LINK_RESET;
445 case LINK_ESTABLISH_EVT:
446 case LINK_SYNCH_BEGIN_EVT:
448 case LINK_SYNCH_END_EVT:
449 l->state = LINK_ESTABLISHED;
451 case LINK_FAILOVER_BEGIN_EVT:
452 case LINK_FAILOVER_END_EVT:
458 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
462 pr_err("Illegal FSM event %x in state %x on link %s\n",
463 evt, l->state, l->name);
467 /* link_profile_stats - update statistical profiling of traffic
469 static void link_profile_stats(struct tipc_link *l)
472 struct tipc_msg *msg;
475 /* Update counters used in statistical profiling of send traffic */
476 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
477 l->stats.queue_sz_counts++;
479 skb = skb_peek(&l->transmq);
483 length = msg_size(msg);
485 if (msg_user(msg) == MSG_FRAGMENTER) {
486 if (msg_type(msg) != FIRST_FRAGMENT)
488 length = msg_size(msg_get_wrapped(msg));
490 l->stats.msg_lengths_total += length;
491 l->stats.msg_length_counts++;
493 l->stats.msg_length_profile[0]++;
494 else if (length <= 256)
495 l->stats.msg_length_profile[1]++;
496 else if (length <= 1024)
497 l->stats.msg_length_profile[2]++;
498 else if (length <= 4096)
499 l->stats.msg_length_profile[3]++;
500 else if (length <= 16384)
501 l->stats.msg_length_profile[4]++;
502 else if (length <= 32768)
503 l->stats.msg_length_profile[5]++;
505 l->stats.msg_length_profile[6]++;
508 /* tipc_link_timeout - perform periodic task as instructed from node timeout
510 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
513 int mtyp = STATE_MSG;
517 link_profile_stats(l);
520 case LINK_ESTABLISHED:
522 if (!l->silent_intv_cnt) {
523 if (tipc_bclink_acks_missing(l->owner))
525 } else if (l->silent_intv_cnt <= l->abort_limit) {
529 rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
531 l->silent_intv_cnt++;
537 case LINK_ESTABLISHING:
541 case LINK_PEER_RESET:
543 case LINK_FAILINGOVER:
550 tipc_link_build_proto_msg(l, mtyp, prb, 0, 0, 0, xmitq);
556 * link_schedule_user - schedule a message sender for wakeup after congestion
557 * @link: congested link
558 * @list: message that was attempted sent
559 * Create pseudo msg to send back to user when congestion abates
560 * Does not consume buffer list
562 static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list)
564 struct tipc_msg *msg = buf_msg(skb_peek(list));
565 int imp = msg_importance(msg);
566 u32 oport = msg_origport(msg);
567 u32 addr = link_own_addr(link);
570 /* This really cannot happen... */
571 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
572 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
575 /* Non-blocking sender: */
576 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending)
579 /* Create and schedule wakeup pseudo message */
580 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
581 addr, addr, oport, 0, 0);
584 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list);
585 TIPC_SKB_CB(skb)->chain_imp = imp;
586 skb_queue_tail(&link->wakeupq, skb);
587 link->stats.link_congs++;
592 * link_prepare_wakeup - prepare users for wakeup after congestion
593 * @link: congested link
594 * Move a number of waiting users, as permitted by available space in
595 * the send queue, from link wait queue to node wait queue for wakeup
597 void link_prepare_wakeup(struct tipc_link *l)
599 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
601 struct sk_buff *skb, *tmp;
603 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
604 imp = TIPC_SKB_CB(skb)->chain_imp;
605 lim = l->window + l->backlog[imp].limit;
606 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
607 if ((pnd[imp] + l->backlog[imp].len) >= lim)
609 skb_unlink(skb, &l->wakeupq);
610 skb_queue_tail(l->inputq, skb);
615 * tipc_link_reset_fragments - purge link's inbound message fragments queue
616 * @l_ptr: pointer to link
618 void tipc_link_reset_fragments(struct tipc_link *l_ptr)
620 kfree_skb(l_ptr->reasm_buf);
621 l_ptr->reasm_buf = NULL;
624 void tipc_link_purge_backlog(struct tipc_link *l)
626 __skb_queue_purge(&l->backlogq);
627 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
628 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
629 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
630 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
631 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
635 * tipc_link_purge_queues - purge all pkt queues associated with link
636 * @l_ptr: pointer to link
638 void tipc_link_purge_queues(struct tipc_link *l_ptr)
640 __skb_queue_purge(&l_ptr->deferdq);
641 __skb_queue_purge(&l_ptr->transmq);
642 tipc_link_purge_backlog(l_ptr);
643 tipc_link_reset_fragments(l_ptr);
646 void tipc_link_reset(struct tipc_link *l)
648 /* Link is down, accept any session */
649 l->peer_session = WILDCARD_SESSION;
651 /* If peer is up, it only accepts an incremented session number */
652 msg_set_session(l->pmsg, msg_session(l->pmsg) + 1);
654 /* Prepare for renewed mtu size negotiation */
655 l->mtu = l->advertised_mtu;
657 /* Clean up all queues: */
658 __skb_queue_purge(&l->transmq);
659 __skb_queue_purge(&l->deferdq);
660 skb_queue_splice_init(&l->wakeupq, l->inputq);
662 tipc_link_purge_backlog(l);
663 kfree_skb(l->reasm_buf);
664 kfree_skb(l->failover_reasm_skb);
666 l->failover_reasm_skb = NULL;
671 l->silent_intv_cnt = 0;
672 l->stats.recv_info = 0;
674 link_reset_statistics(l);
678 * __tipc_link_xmit(): same as tipc_link_xmit, but destlink is known & locked
680 * @list: chain of buffers containing message
682 * Consumes the buffer chain, except when returning an error code,
683 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
684 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
686 int __tipc_link_xmit(struct net *net, struct tipc_link *link,
687 struct sk_buff_head *list)
689 struct tipc_msg *msg = buf_msg(skb_peek(list));
690 unsigned int maxwin = link->window;
691 unsigned int i, imp = msg_importance(msg);
692 uint mtu = link->mtu;
693 u16 ack = mod(link->rcv_nxt - 1);
694 u16 seqno = link->snd_nxt;
695 u16 bc_last_in = link->owner->bclink.last_in;
696 struct tipc_media_addr *addr = link->media_addr;
697 struct sk_buff_head *transmq = &link->transmq;
698 struct sk_buff_head *backlogq = &link->backlogq;
699 struct sk_buff *skb, *bskb;
701 /* Match msg importance against this and all higher backlog limits: */
702 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
703 if (unlikely(link->backlog[i].len >= link->backlog[i].limit))
704 return link_schedule_user(link, list);
706 if (unlikely(msg_size(msg) > mtu))
709 /* Prepare each packet for sending, and add to relevant queue: */
710 while (skb_queue_len(list)) {
711 skb = skb_peek(list);
713 msg_set_seqno(msg, seqno);
714 msg_set_ack(msg, ack);
715 msg_set_bcast_ack(msg, bc_last_in);
717 if (likely(skb_queue_len(transmq) < maxwin)) {
719 __skb_queue_tail(transmq, skb);
720 tipc_bearer_send(net, link->bearer_id, skb, addr);
721 link->rcv_unacked = 0;
725 if (tipc_msg_bundle(skb_peek_tail(backlogq), msg, mtu)) {
726 kfree_skb(__skb_dequeue(list));
727 link->stats.sent_bundled++;
730 if (tipc_msg_make_bundle(&bskb, msg, mtu, link->addr)) {
731 kfree_skb(__skb_dequeue(list));
732 __skb_queue_tail(backlogq, bskb);
733 link->backlog[msg_importance(buf_msg(bskb))].len++;
734 link->stats.sent_bundled++;
735 link->stats.sent_bundles++;
738 link->backlog[imp].len += skb_queue_len(list);
739 skb_queue_splice_tail_init(list, backlogq);
741 link->snd_nxt = seqno;
746 * tipc_link_xmit(): enqueue buffer list according to queue situation
748 * @list: chain of buffers containing message
749 * @xmitq: returned list of packets to be sent by caller
751 * Consumes the buffer chain, except when returning -ELINKCONG,
752 * since the caller then may want to make more send attempts.
753 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
754 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
756 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
757 struct sk_buff_head *xmitq)
759 struct tipc_msg *hdr = buf_msg(skb_peek(list));
760 unsigned int maxwin = l->window;
761 unsigned int i, imp = msg_importance(hdr);
762 unsigned int mtu = l->mtu;
763 u16 ack = l->rcv_nxt - 1;
764 u16 seqno = l->snd_nxt;
765 u16 bc_last_in = l->owner->bclink.last_in;
766 struct sk_buff_head *transmq = &l->transmq;
767 struct sk_buff_head *backlogq = &l->backlogq;
768 struct sk_buff *skb, *_skb, *bskb;
770 /* Match msg importance against this and all higher backlog limits: */
771 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
772 if (unlikely(l->backlog[i].len >= l->backlog[i].limit))
773 return link_schedule_user(l, list);
775 if (unlikely(msg_size(hdr) > mtu))
778 /* Prepare each packet for sending, and add to relevant queue: */
779 while (skb_queue_len(list)) {
780 skb = skb_peek(list);
782 msg_set_seqno(hdr, seqno);
783 msg_set_ack(hdr, ack);
784 msg_set_bcast_ack(hdr, bc_last_in);
786 if (likely(skb_queue_len(transmq) < maxwin)) {
787 _skb = skb_clone(skb, GFP_ATOMIC);
791 __skb_queue_tail(transmq, skb);
792 __skb_queue_tail(xmitq, _skb);
793 TIPC_SKB_CB(skb)->ackers = l->ackers;
798 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) {
799 kfree_skb(__skb_dequeue(list));
800 l->stats.sent_bundled++;
803 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) {
804 kfree_skb(__skb_dequeue(list));
805 __skb_queue_tail(backlogq, bskb);
806 l->backlog[msg_importance(buf_msg(bskb))].len++;
807 l->stats.sent_bundled++;
808 l->stats.sent_bundles++;
811 l->backlog[imp].len += skb_queue_len(list);
812 skb_queue_splice_tail_init(list, backlogq);
819 * tipc_link_sync_rcv - synchronize broadcast link endpoints.
820 * Receive the sequence number where we should start receiving and
821 * acking broadcast packets from a newly added peer node, and open
822 * up for reception of such packets.
824 * Called with node locked
826 static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf)
828 struct tipc_msg *msg = buf_msg(buf);
830 n->bclink.last_sent = n->bclink.last_in = msg_last_bcast(msg);
831 n->bclink.recv_permitted = true;
836 * tipc_link_push_packets - push unsent packets to bearer
838 * Push out the unsent messages of a link where congestion
839 * has abated. Node is locked.
841 * Called with node locked
843 void tipc_link_push_packets(struct tipc_link *link)
846 struct tipc_msg *msg;
847 u16 seqno = link->snd_nxt;
848 u16 ack = mod(link->rcv_nxt - 1);
850 while (skb_queue_len(&link->transmq) < link->window) {
851 skb = __skb_dequeue(&link->backlogq);
854 TIPC_SKB_CB(skb)->ackers = link->ackers;
856 link->backlog[msg_importance(msg)].len--;
857 msg_set_ack(msg, ack);
858 msg_set_seqno(msg, seqno);
859 seqno = mod(seqno + 1);
860 msg_set_bcast_ack(msg, link->owner->bclink.last_in);
861 link->rcv_unacked = 0;
862 __skb_queue_tail(&link->transmq, skb);
863 tipc_bearer_send(link->owner->net, link->bearer_id,
864 skb, link->media_addr);
866 link->snd_nxt = seqno;
869 void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq)
871 struct sk_buff *skb, *_skb;
872 struct tipc_msg *hdr;
873 u16 seqno = l->snd_nxt;
874 u16 ack = l->rcv_nxt - 1;
876 while (skb_queue_len(&l->transmq) < l->window) {
877 skb = skb_peek(&l->backlogq);
880 _skb = skb_clone(skb, GFP_ATOMIC);
883 __skb_dequeue(&l->backlogq);
885 l->backlog[msg_importance(hdr)].len--;
886 __skb_queue_tail(&l->transmq, skb);
887 __skb_queue_tail(xmitq, _skb);
888 TIPC_SKB_CB(skb)->ackers = l->ackers;
889 msg_set_ack(hdr, ack);
890 msg_set_seqno(hdr, seqno);
891 msg_set_bcast_ack(hdr, l->owner->bclink.last_in);
898 static void link_retransmit_failure(struct tipc_link *l_ptr,
901 struct tipc_msg *msg = buf_msg(buf);
902 struct net *net = l_ptr->owner->net;
904 pr_warn("Retransmission failure on link <%s>\n", l_ptr->name);
907 /* Handle failure on standard link */
908 link_print(l_ptr, "Resetting link ");
909 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
910 msg_user(msg), msg_type(msg), msg_size(msg),
912 pr_info("sqno %u, prev: %x, src: %x\n",
913 msg_seqno(msg), msg_prevnode(msg), msg_orignode(msg));
915 /* Handle failure on broadcast link */
916 struct tipc_node *n_ptr;
917 char addr_string[16];
919 pr_info("Msg seq number: %u, ", msg_seqno(msg));
920 pr_cont("Outstanding acks: %u\n", TIPC_SKB_CB(buf)->ackers);
922 n_ptr = tipc_bclink_retransmit_to(net);
924 tipc_addr_string_fill(addr_string, n_ptr->addr);
925 pr_info("Broadcast link info for %s\n", addr_string);
926 pr_info("Reception permitted: %d, Acked: %u\n",
927 n_ptr->bclink.recv_permitted,
928 n_ptr->bclink.acked);
929 pr_info("Last in: %u, Oos state: %u, Last sent: %u\n",
930 n_ptr->bclink.last_in,
931 n_ptr->bclink.oos_state,
932 n_ptr->bclink.last_sent);
934 n_ptr->action_flags |= TIPC_BCAST_RESET;
935 l_ptr->stale_count = 0;
939 void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *skb,
942 struct tipc_msg *msg;
949 /* Detect repeated retransmit failures */
950 if (l_ptr->last_retransm == msg_seqno(msg)) {
951 if (++l_ptr->stale_count > 100) {
952 link_retransmit_failure(l_ptr, skb);
956 l_ptr->last_retransm = msg_seqno(msg);
957 l_ptr->stale_count = 1;
960 skb_queue_walk_from(&l_ptr->transmq, skb) {
964 msg_set_ack(msg, mod(l_ptr->rcv_nxt - 1));
965 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
966 tipc_bearer_send(l_ptr->owner->net, l_ptr->bearer_id, skb,
969 l_ptr->stats.retransmitted++;
973 int tipc_link_retrans(struct tipc_link *l, u16 from, u16 to,
974 struct sk_buff_head *xmitq)
976 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
977 struct tipc_msg *hdr;
978 u16 ack = l->rcv_nxt - 1;
979 u16 bc_ack = l->owner->bclink.last_in;
984 /* Detect repeated retransmit failures on same packet */
985 if (likely(l->last_retransm != buf_seqno(skb))) {
986 l->last_retransm = buf_seqno(skb);
988 } else if (++l->stale_count > 100) {
989 link_retransmit_failure(l, skb);
990 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
993 /* Move forward to where retransmission should start */
994 skb_queue_walk(&l->transmq, skb) {
995 if (!less(buf_seqno(skb), from))
999 skb_queue_walk_from(&l->transmq, skb) {
1000 if (more(buf_seqno(skb), to))
1003 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
1006 hdr = buf_msg(_skb);
1007 msg_set_ack(hdr, ack);
1008 msg_set_bcast_ack(hdr, bc_ack);
1009 _skb->priority = TC_PRIO_CONTROL;
1010 __skb_queue_tail(xmitq, _skb);
1011 l->stats.retransmitted++;
1016 /* tipc_data_input - deliver data and name distr msgs to upper layer
1018 * Consumes buffer if message is of right type
1019 * Node lock must be held
1021 static bool tipc_data_input(struct tipc_link *link, struct sk_buff *skb,
1022 struct sk_buff_head *inputq)
1024 struct tipc_node *node = link->owner;
1026 switch (msg_user(buf_msg(skb))) {
1027 case TIPC_LOW_IMPORTANCE:
1028 case TIPC_MEDIUM_IMPORTANCE:
1029 case TIPC_HIGH_IMPORTANCE:
1030 case TIPC_CRITICAL_IMPORTANCE:
1032 skb_queue_tail(inputq, skb);
1034 case NAME_DISTRIBUTOR:
1035 node->bclink.recv_permitted = true;
1036 skb_queue_tail(link->namedq, skb);
1039 case TUNNEL_PROTOCOL:
1040 case MSG_FRAGMENTER:
1041 case BCAST_PROTOCOL:
1044 pr_warn("Dropping received illegal msg type\n");
1050 /* tipc_link_input - process packet that has passed link protocol check
1054 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1055 struct sk_buff_head *inputq)
1057 struct tipc_node *node = l->owner;
1058 struct tipc_msg *hdr = buf_msg(skb);
1059 struct sk_buff **reasm_skb = &l->reasm_buf;
1060 struct sk_buff *iskb;
1061 struct sk_buff_head tmpq;
1062 int usr = msg_user(hdr);
1067 if (unlikely(usr == TUNNEL_PROTOCOL)) {
1068 if (msg_type(hdr) == SYNCH_MSG) {
1069 __skb_queue_purge(&l->deferdq);
1072 if (!tipc_msg_extract(skb, &iskb, &ipos))
1077 if (less(msg_seqno(hdr), l->drop_point))
1079 if (tipc_data_input(l, skb, inputq))
1081 usr = msg_user(hdr);
1082 reasm_skb = &l->failover_reasm_skb;
1085 if (usr == MSG_BUNDLER) {
1086 skb_queue_head_init(&tmpq);
1087 l->stats.recv_bundles++;
1088 l->stats.recv_bundled += msg_msgcnt(hdr);
1089 while (tipc_msg_extract(skb, &iskb, &pos))
1090 tipc_data_input(l, iskb, &tmpq);
1091 tipc_skb_queue_splice_tail(&tmpq, inputq);
1093 } else if (usr == MSG_FRAGMENTER) {
1094 l->stats.recv_fragments++;
1095 if (tipc_buf_append(reasm_skb, &skb)) {
1096 l->stats.recv_fragmented++;
1097 tipc_data_input(l, skb, inputq);
1098 } else if (!*reasm_skb) {
1099 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1102 } else if (usr == BCAST_PROTOCOL) {
1103 tipc_link_sync_rcv(node, skb);
1111 static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
1113 bool released = false;
1114 struct sk_buff *skb, *tmp;
1116 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1117 if (more(buf_seqno(skb), acked))
1119 __skb_unlink(skb, &l->transmq);
1126 /* tipc_link_build_ack_msg: prepare link acknowledge message for transmission
1128 void tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1131 l->stats.sent_acks++;
1132 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1135 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1137 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1139 int mtyp = RESET_MSG;
1141 if (l->state == LINK_ESTABLISHING)
1142 mtyp = ACTIVATE_MSG;
1144 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq);
1147 /* tipc_link_build_nack_msg: prepare link nack message for transmission
1149 static void tipc_link_build_nack_msg(struct tipc_link *l,
1150 struct sk_buff_head *xmitq)
1152 u32 def_cnt = ++l->stats.deferred_recv;
1154 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
1155 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1158 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1159 * @l: the link that should handle the message
1161 * @xmitq: queue to place packets to be sent after this call
1163 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1164 struct sk_buff_head *xmitq)
1166 struct sk_buff_head *defq = &l->deferdq;
1167 struct tipc_msg *hdr;
1168 u16 seqno, rcv_nxt, win_lim;
1173 seqno = msg_seqno(hdr);
1174 rcv_nxt = l->rcv_nxt;
1175 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1177 /* Verify and update link state */
1178 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1179 return tipc_link_proto_rcv(l, skb, xmitq);
1181 if (unlikely(!link_is_up(l))) {
1182 if (l->state == LINK_ESTABLISHING)
1183 rc = TIPC_LINK_UP_EVT;
1187 /* Don't send probe at next timeout expiration */
1188 l->silent_intv_cnt = 0;
1190 /* Drop if outside receive window */
1191 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1192 l->stats.duplicates++;
1196 /* Forward queues and wake up waiting users */
1197 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1198 tipc_link_advance_backlog(l, xmitq);
1199 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1200 link_prepare_wakeup(l);
1203 /* Defer delivery if sequence gap */
1204 if (unlikely(seqno != rcv_nxt)) {
1205 __tipc_skb_queue_sorted(defq, seqno, skb);
1206 tipc_link_build_nack_msg(l, xmitq);
1210 /* Deliver packet */
1212 l->stats.recv_info++;
1213 if (!tipc_data_input(l, skb, l->inputq))
1214 rc = tipc_link_input(l, skb, l->inputq);
1217 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1218 tipc_link_build_ack_msg(l, xmitq);
1220 } while ((skb = __skb_dequeue(defq)));
1229 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1231 * Returns increase in queue length (i.e. 0 or 1)
1233 u32 tipc_link_defer_pkt(struct sk_buff_head *list, struct sk_buff *skb)
1235 struct sk_buff *skb1;
1236 u16 seq_no = buf_seqno(skb);
1239 if (skb_queue_empty(list)) {
1240 __skb_queue_tail(list, skb);
1245 if (less(buf_seqno(skb_peek_tail(list)), seq_no)) {
1246 __skb_queue_tail(list, skb);
1250 /* Locate insertion point in queue, then insert; discard if duplicate */
1251 skb_queue_walk(list, skb1) {
1252 u16 curr_seqno = buf_seqno(skb1);
1254 if (seq_no == curr_seqno) {
1259 if (less(seq_no, curr_seqno))
1263 __skb_queue_before(list, skb1, skb);
1268 * Send protocol message to the other endpoint.
1270 void tipc_link_proto_xmit(struct tipc_link *l, u32 msg_typ, int probe_msg,
1271 u32 gap, u32 tolerance, u32 priority)
1273 struct sk_buff *skb = NULL;
1274 struct sk_buff_head xmitq;
1276 __skb_queue_head_init(&xmitq);
1277 tipc_link_build_proto_msg(l, msg_typ, probe_msg, gap,
1278 tolerance, priority, &xmitq);
1279 skb = __skb_dequeue(&xmitq);
1282 tipc_bearer_send(l->owner->net, l->bearer_id, skb, l->media_addr);
1287 /* tipc_link_build_proto_msg: prepare link protocol message for transmission
1289 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1290 u16 rcvgap, int tolerance, int priority,
1291 struct sk_buff_head *xmitq)
1293 struct sk_buff *skb = NULL;
1294 struct tipc_msg *hdr = l->pmsg;
1295 u16 snd_nxt = l->snd_nxt;
1296 u16 rcv_nxt = l->rcv_nxt;
1297 u16 rcv_last = rcv_nxt - 1;
1298 int node_up = l->owner->bclink.recv_permitted;
1300 /* Don't send protocol message during reset or link failover */
1301 if (tipc_link_is_blocked(l))
1304 msg_set_type(hdr, mtyp);
1305 msg_set_net_plane(hdr, l->net_plane);
1306 msg_set_bcast_ack(hdr, l->owner->bclink.last_in);
1307 msg_set_last_bcast(hdr, tipc_bclink_get_last_sent(l->owner->net));
1308 msg_set_link_tolerance(hdr, tolerance);
1309 msg_set_linkprio(hdr, priority);
1310 msg_set_redundant_link(hdr, node_up);
1311 msg_set_seq_gap(hdr, 0);
1313 /* Compatibility: created msg must not be in sequence with pkt flow */
1314 msg_set_seqno(hdr, snd_nxt + U16_MAX / 2);
1316 if (mtyp == STATE_MSG) {
1317 if (!tipc_link_is_up(l))
1319 msg_set_next_sent(hdr, snd_nxt);
1321 /* Override rcvgap if there are packets in deferred queue */
1322 if (!skb_queue_empty(&l->deferdq))
1323 rcvgap = buf_seqno(skb_peek(&l->deferdq)) - rcv_nxt;
1325 msg_set_seq_gap(hdr, rcvgap);
1326 l->stats.sent_nacks++;
1328 msg_set_ack(hdr, rcv_last);
1329 msg_set_probe(hdr, probe);
1331 l->stats.sent_probes++;
1332 l->stats.sent_states++;
1334 /* RESET_MSG or ACTIVATE_MSG */
1335 msg_set_max_pkt(hdr, l->advertised_mtu);
1336 msg_set_ack(hdr, l->rcv_nxt - 1);
1337 msg_set_next_sent(hdr, 1);
1339 skb = tipc_buf_acquire(msg_size(hdr));
1342 skb_copy_to_linear_data(skb, hdr, msg_size(hdr));
1343 skb->priority = TC_PRIO_CONTROL;
1344 __skb_queue_tail(xmitq, skb);
1347 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1348 * with contents of the link's transmit and backlog queues.
1350 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1351 int mtyp, struct sk_buff_head *xmitq)
1353 struct sk_buff *skb, *tnlskb;
1354 struct tipc_msg *hdr, tnlhdr;
1355 struct sk_buff_head *queue = &l->transmq;
1356 struct sk_buff_head tmpxq, tnlq;
1357 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1362 skb_queue_head_init(&tnlq);
1363 skb_queue_head_init(&tmpxq);
1365 /* At least one packet required for safe algorithm => add dummy */
1366 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1367 BASIC_H_SIZE, 0, l->addr, link_own_addr(l),
1368 0, 0, TIPC_ERR_NO_PORT);
1370 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1373 skb_queue_tail(&tnlq, skb);
1374 tipc_link_xmit(l, &tnlq, &tmpxq);
1375 __skb_queue_purge(&tmpxq);
1377 /* Initialize reusable tunnel packet header */
1378 tipc_msg_init(link_own_addr(l), &tnlhdr, TUNNEL_PROTOCOL,
1379 mtyp, INT_H_SIZE, l->addr);
1380 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
1381 msg_set_msgcnt(&tnlhdr, pktcnt);
1382 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1384 /* Wrap each packet into a tunnel packet */
1385 skb_queue_walk(queue, skb) {
1387 if (queue == &l->backlogq)
1388 msg_set_seqno(hdr, seqno++);
1389 pktlen = msg_size(hdr);
1390 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1391 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE);
1393 pr_warn("%sunable to send packet\n", link_co_err);
1396 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1397 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1398 __skb_queue_tail(&tnlq, tnlskb);
1400 if (queue != &l->backlogq) {
1401 queue = &l->backlogq;
1405 tipc_link_xmit(tnl, &tnlq, xmitq);
1407 if (mtyp == FAILOVER_MSG) {
1408 tnl->drop_point = l->rcv_nxt;
1409 tnl->failover_reasm_skb = l->reasm_buf;
1410 l->reasm_buf = NULL;
1414 /* tipc_link_proto_rcv(): receive link level protocol message :
1415 * Note that network plane id propagates through the network, and may
1416 * change at any time. The node with lowest numerical id determines
1419 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1420 struct sk_buff_head *xmitq)
1422 struct tipc_msg *hdr = buf_msg(skb);
1424 u16 ack = msg_ack(hdr);
1425 u16 gap = msg_seq_gap(hdr);
1426 u16 peers_snd_nxt = msg_next_sent(hdr);
1427 u16 peers_tol = msg_link_tolerance(hdr);
1428 u16 peers_prio = msg_linkprio(hdr);
1429 u16 rcv_nxt = l->rcv_nxt;
1430 int mtyp = msg_type(hdr);
1434 if (tipc_link_is_blocked(l))
1437 if (link_own_addr(l) > msg_prevnode(hdr))
1438 l->net_plane = msg_net_plane(hdr);
1443 /* Ignore duplicate RESET with old session number */
1444 if ((less_eq(msg_session(hdr), l->peer_session)) &&
1445 (l->peer_session != WILDCARD_SESSION))
1451 /* Complete own link name with peer's interface name */
1452 if_name = strrchr(l->name, ':') + 1;
1453 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1455 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1457 strncpy(if_name, msg_data(hdr), TIPC_MAX_IF_NAME);
1459 /* Update own tolerance if peer indicates a non-zero value */
1460 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1461 l->tolerance = peers_tol;
1463 /* Update own priority if peer's priority is higher */
1464 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1465 l->priority = peers_prio;
1467 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
1468 if ((mtyp == RESET_MSG) || !link_is_up(l))
1469 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
1471 /* ACTIVATE_MSG takes up link if it was already locally reset */
1472 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING))
1473 rc = TIPC_LINK_UP_EVT;
1475 l->peer_session = msg_session(hdr);
1476 l->peer_bearer_id = msg_bearer_id(hdr);
1477 if (l->mtu > msg_max_pkt(hdr))
1478 l->mtu = msg_max_pkt(hdr);
1483 /* Update own tolerance if peer indicates a non-zero value */
1484 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1485 l->tolerance = peers_tol;
1487 l->silent_intv_cnt = 0;
1488 l->stats.recv_states++;
1490 l->stats.recv_probes++;
1492 if (!link_is_up(l)) {
1493 if (l->state == LINK_ESTABLISHING)
1494 rc = TIPC_LINK_UP_EVT;
1498 /* Send NACK if peer has sent pkts we haven't received yet */
1499 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
1500 rcvgap = peers_snd_nxt - l->rcv_nxt;
1501 if (rcvgap || (msg_probe(hdr)))
1502 tipc_link_build_proto_msg(l, STATE_MSG, 0, rcvgap,
1504 tipc_link_release_pkts(l, ack);
1506 /* If NACK, retransmit will now start at right position */
1508 rc = tipc_link_retrans(l, ack + 1, ack + gap, xmitq);
1509 l->stats.recv_nacks++;
1512 tipc_link_advance_backlog(l, xmitq);
1513 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1514 link_prepare_wakeup(l);
1521 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1523 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE);
1526 l->backlog[TIPC_LOW_IMPORTANCE].limit = win / 2;
1527 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = win;
1528 l->backlog[TIPC_HIGH_IMPORTANCE].limit = win / 2 * 3;
1529 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = win * 2;
1530 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1533 /* tipc_link_find_owner - locate owner node of link by link's name
1534 * @net: the applicable net namespace
1535 * @name: pointer to link name string
1536 * @bearer_id: pointer to index in 'node->links' array where the link was found.
1538 * Returns pointer to node owning the link, or 0 if no matching link is found.
1540 static struct tipc_node *tipc_link_find_owner(struct net *net,
1541 const char *link_name,
1542 unsigned int *bearer_id)
1544 struct tipc_net *tn = net_generic(net, tipc_net_id);
1545 struct tipc_link *l_ptr;
1546 struct tipc_node *n_ptr;
1547 struct tipc_node *found_node = NULL;
1552 list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
1553 tipc_node_lock(n_ptr);
1554 for (i = 0; i < MAX_BEARERS; i++) {
1555 l_ptr = n_ptr->links[i].link;
1556 if (l_ptr && !strcmp(l_ptr->name, link_name)) {
1562 tipc_node_unlock(n_ptr);
1572 * link_reset_statistics - reset link statistics
1573 * @l_ptr: pointer to link
1575 static void link_reset_statistics(struct tipc_link *l_ptr)
1577 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
1578 l_ptr->stats.sent_info = l_ptr->snd_nxt;
1579 l_ptr->stats.recv_info = l_ptr->rcv_nxt;
1582 static void link_print(struct tipc_link *l, const char *str)
1584 struct sk_buff *hskb = skb_peek(&l->transmq);
1585 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
1586 u16 tail = l->snd_nxt - 1;
1588 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
1589 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
1590 skb_queue_len(&l->transmq), head, tail,
1591 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
1594 /* Parse and validate nested (link) properties valid for media, bearer and link
1596 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1600 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1601 tipc_nl_prop_policy);
1605 if (props[TIPC_NLA_PROP_PRIO]) {
1608 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1609 if (prio > TIPC_MAX_LINK_PRI)
1613 if (props[TIPC_NLA_PROP_TOL]) {
1616 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1617 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1621 if (props[TIPC_NLA_PROP_WIN]) {
1624 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1625 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1632 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info)
1638 struct tipc_link *link;
1639 struct tipc_node *node;
1640 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
1641 struct net *net = sock_net(skb->sk);
1643 if (!info->attrs[TIPC_NLA_LINK])
1646 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
1647 info->attrs[TIPC_NLA_LINK],
1648 tipc_nl_link_policy);
1652 if (!attrs[TIPC_NLA_LINK_NAME])
1655 name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
1657 if (strcmp(name, tipc_bclink_name) == 0)
1658 return tipc_nl_bc_link_set(net, attrs);
1660 node = tipc_link_find_owner(net, name, &bearer_id);
1664 tipc_node_lock(node);
1666 link = node->links[bearer_id].link;
1672 if (attrs[TIPC_NLA_LINK_PROP]) {
1673 struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1675 err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
1682 if (props[TIPC_NLA_PROP_TOL]) {
1685 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1686 link->tolerance = tol;
1687 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0);
1689 if (props[TIPC_NLA_PROP_PRIO]) {
1692 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1693 link->priority = prio;
1694 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio);
1696 if (props[TIPC_NLA_PROP_WIN]) {
1699 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1700 tipc_link_set_queue_limits(link, win);
1705 tipc_node_unlock(node);
1710 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1713 struct nlattr *stats;
1720 struct nla_map map[] = {
1721 {TIPC_NLA_STATS_RX_INFO, s->recv_info},
1722 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1723 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1724 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1725 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1726 {TIPC_NLA_STATS_TX_INFO, s->sent_info},
1727 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1728 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1729 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1730 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1731 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1732 s->msg_length_counts : 1},
1733 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1734 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1735 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1736 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1737 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1738 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1739 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1740 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1741 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1742 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1743 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1744 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1745 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1746 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1747 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1748 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1749 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1750 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1751 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1752 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1753 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1754 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1755 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1758 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1762 for (i = 0; i < ARRAY_SIZE(map); i++)
1763 if (nla_put_u32(skb, map[i].key, map[i].val))
1766 nla_nest_end(skb, stats);
1770 nla_nest_cancel(skb, stats);
1775 /* Caller should hold appropriate locks to protect the link */
1776 static int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1777 struct tipc_link *link, int nlflags)
1781 struct nlattr *attrs;
1782 struct nlattr *prop;
1783 struct tipc_net *tn = net_generic(net, tipc_net_id);
1785 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1786 nlflags, TIPC_NL_LINK_GET);
1790 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1794 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
1796 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
1797 tipc_cluster_mask(tn->own_addr)))
1799 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
1801 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->rcv_nxt))
1803 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->snd_nxt))
1806 if (tipc_link_is_up(link))
1807 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1809 if (tipc_link_is_active(link))
1810 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
1813 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1816 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1818 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
1820 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
1823 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1825 nla_nest_end(msg->skb, prop);
1827 err = __tipc_nl_add_stats(msg->skb, &link->stats);
1831 nla_nest_end(msg->skb, attrs);
1832 genlmsg_end(msg->skb, hdr);
1837 nla_nest_cancel(msg->skb, prop);
1839 nla_nest_cancel(msg->skb, attrs);
1841 genlmsg_cancel(msg->skb, hdr);
1846 /* Caller should hold node lock */
1847 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
1848 struct tipc_node *node, u32 *prev_link)
1853 for (i = *prev_link; i < MAX_BEARERS; i++) {
1856 if (!node->links[i].link)
1859 err = __tipc_nl_add_link(net, msg,
1860 node->links[i].link, NLM_F_MULTI);
1869 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
1871 struct net *net = sock_net(skb->sk);
1872 struct tipc_net *tn = net_generic(net, tipc_net_id);
1873 struct tipc_node *node;
1874 struct tipc_nl_msg msg;
1875 u32 prev_node = cb->args[0];
1876 u32 prev_link = cb->args[1];
1877 int done = cb->args[2];
1884 msg.portid = NETLINK_CB(cb->skb).portid;
1885 msg.seq = cb->nlh->nlmsg_seq;
1889 node = tipc_node_find(net, prev_node);
1891 /* We never set seq or call nl_dump_check_consistent()
1892 * this means that setting prev_seq here will cause the
1893 * consistence check to fail in the netlink callback
1894 * handler. Resulting in the last NLMSG_DONE message
1895 * having the NLM_F_DUMP_INTR flag set.
1900 tipc_node_put(node);
1902 list_for_each_entry_continue_rcu(node, &tn->node_list,
1904 tipc_node_lock(node);
1905 err = __tipc_nl_add_node_links(net, &msg, node,
1907 tipc_node_unlock(node);
1911 prev_node = node->addr;
1914 err = tipc_nl_add_bc_link(net, &msg);
1918 list_for_each_entry_rcu(node, &tn->node_list, list) {
1919 tipc_node_lock(node);
1920 err = __tipc_nl_add_node_links(net, &msg, node,
1922 tipc_node_unlock(node);
1926 prev_node = node->addr;
1933 cb->args[0] = prev_node;
1934 cb->args[1] = prev_link;
1940 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info)
1942 struct net *net = genl_info_net(info);
1943 struct tipc_nl_msg msg;
1947 msg.portid = info->snd_portid;
1948 msg.seq = info->snd_seq;
1950 if (!info->attrs[TIPC_NLA_LINK_NAME])
1952 name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]);
1954 msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
1958 if (strcmp(name, tipc_bclink_name) == 0) {
1959 err = tipc_nl_add_bc_link(net, &msg);
1961 nlmsg_free(msg.skb);
1966 struct tipc_node *node;
1967 struct tipc_link *link;
1969 node = tipc_link_find_owner(net, name, &bearer_id);
1973 tipc_node_lock(node);
1974 link = node->links[bearer_id].link;
1976 tipc_node_unlock(node);
1977 nlmsg_free(msg.skb);
1981 err = __tipc_nl_add_link(net, &msg, link, 0);
1982 tipc_node_unlock(node);
1984 nlmsg_free(msg.skb);
1989 return genlmsg_reply(msg.skb, info);
1992 int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
1996 unsigned int bearer_id;
1997 struct tipc_link *link;
1998 struct tipc_node *node;
1999 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2000 struct net *net = sock_net(skb->sk);
2002 if (!info->attrs[TIPC_NLA_LINK])
2005 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2006 info->attrs[TIPC_NLA_LINK],
2007 tipc_nl_link_policy);
2011 if (!attrs[TIPC_NLA_LINK_NAME])
2014 link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2016 if (strcmp(link_name, tipc_bclink_name) == 0) {
2017 err = tipc_bclink_reset_stats(net);
2023 node = tipc_link_find_owner(net, link_name, &bearer_id);
2027 tipc_node_lock(node);
2029 link = node->links[bearer_id].link;
2031 tipc_node_unlock(node);
2035 link_reset_statistics(link);
2037 tipc_node_unlock(node);