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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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 changeover error, ";
52 static const char *link_rst_msg = "Resetting link ";
53 static const char *link_unk_evt = "Unknown link event ";
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 * Out-of-range value for link session numbers
82 #define INVALID_SESSION 0x10000
87 #define STARTING_EVT 856384768 /* link processing trigger */
88 #define TRAFFIC_MSG_EVT 560815u /* rx'd ??? */
89 #define SILENCE_EVT 560817u /* timer dicovered silence from peer */
92 * State value stored in 'failover_pkts'
94 #define FIRST_FAILOVER 0xffffu
96 static void link_handle_out_of_seq_msg(struct tipc_link *link,
98 static void tipc_link_proto_rcv(struct tipc_link *link,
100 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tol);
101 static void link_state_event(struct tipc_link *l_ptr, u32 event);
102 static void link_reset_statistics(struct tipc_link *l_ptr);
103 static void link_print(struct tipc_link *l_ptr, const char *str);
104 static void tipc_link_sync_xmit(struct tipc_link *l);
105 static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf);
106 static void tipc_link_input(struct tipc_link *l, struct sk_buff *skb);
107 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb);
108 static bool tipc_link_failover_rcv(struct tipc_link *l, struct sk_buff **skb);
109 static void link_set_timer(struct tipc_link *link, unsigned long time);
111 * Simple link routines
113 static unsigned int align(unsigned int i)
115 return (i + 3) & ~3u;
118 static void tipc_link_release(struct kref *kref)
120 kfree(container_of(kref, struct tipc_link, ref));
123 static void tipc_link_get(struct tipc_link *l_ptr)
125 kref_get(&l_ptr->ref);
128 static void tipc_link_put(struct tipc_link *l_ptr)
130 kref_put(&l_ptr->ref, tipc_link_release);
133 static struct tipc_link *tipc_parallel_link(struct tipc_link *l)
135 struct tipc_node *n = l->owner;
137 if (node_active_link(n, 0) != l)
138 return node_active_link(n, 0);
139 return node_active_link(n, 1);
143 * Simple non-static link routines (i.e. referenced outside this file)
145 int tipc_link_is_up(struct tipc_link *l_ptr)
149 return link_working_working(l_ptr) || link_working_unknown(l_ptr);
152 int tipc_link_is_active(struct tipc_link *l)
154 struct tipc_node *n = l->owner;
156 return (node_active_link(n, 0) == l) || (node_active_link(n, 1) == l);
160 * link_timeout - handle expiration of link timer
161 * @l_ptr: pointer to link
163 static void link_timeout(unsigned long data)
165 struct tipc_link *l_ptr = (struct tipc_link *)data;
168 tipc_node_lock(l_ptr->owner);
170 /* update counters used in statistical profiling of send traffic */
171 l_ptr->stats.accu_queue_sz += skb_queue_len(&l_ptr->transmq);
172 l_ptr->stats.queue_sz_counts++;
174 skb = skb_peek(&l_ptr->transmq);
176 struct tipc_msg *msg = buf_msg(skb);
177 u32 length = msg_size(msg);
179 if ((msg_user(msg) == MSG_FRAGMENTER) &&
180 (msg_type(msg) == FIRST_FRAGMENT)) {
181 length = msg_size(msg_get_wrapped(msg));
184 l_ptr->stats.msg_lengths_total += length;
185 l_ptr->stats.msg_length_counts++;
187 l_ptr->stats.msg_length_profile[0]++;
188 else if (length <= 256)
189 l_ptr->stats.msg_length_profile[1]++;
190 else if (length <= 1024)
191 l_ptr->stats.msg_length_profile[2]++;
192 else if (length <= 4096)
193 l_ptr->stats.msg_length_profile[3]++;
194 else if (length <= 16384)
195 l_ptr->stats.msg_length_profile[4]++;
196 else if (length <= 32768)
197 l_ptr->stats.msg_length_profile[5]++;
199 l_ptr->stats.msg_length_profile[6]++;
203 /* do all other link processing performed on a periodic basis */
204 if (l_ptr->silent_intv_cnt || tipc_bclink_acks_missing(l_ptr->owner))
205 link_state_event(l_ptr, SILENCE_EVT);
206 l_ptr->silent_intv_cnt++;
207 if (skb_queue_len(&l_ptr->backlogq))
208 tipc_link_push_packets(l_ptr);
209 link_set_timer(l_ptr, l_ptr->keepalive_intv);
210 tipc_node_unlock(l_ptr->owner);
211 tipc_link_put(l_ptr);
214 static void link_set_timer(struct tipc_link *link, unsigned long time)
216 if (!mod_timer(&link->timer, jiffies + time))
221 * tipc_link_create - create a new link
222 * @n_ptr: pointer to associated node
223 * @b_ptr: pointer to associated bearer
224 * @media_addr: media address to use when sending messages over link
226 * Returns pointer to link.
228 struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
229 struct tipc_bearer *b_ptr,
230 const struct tipc_media_addr *media_addr,
231 struct sk_buff_head *inputq,
232 struct sk_buff_head *namedq)
234 struct tipc_net *tn = net_generic(n_ptr->net, tipc_net_id);
235 struct tipc_link *l_ptr;
236 struct tipc_msg *msg;
238 char addr_string[16];
239 u32 peer = n_ptr->addr;
241 if (n_ptr->link_cnt >= MAX_BEARERS) {
242 tipc_addr_string_fill(addr_string, n_ptr->addr);
243 pr_err("Cannot establish %uth link to %s. Max %u allowed.\n",
244 n_ptr->link_cnt, addr_string, MAX_BEARERS);
248 if (n_ptr->links[b_ptr->identity].link) {
249 tipc_addr_string_fill(addr_string, n_ptr->addr);
250 pr_err("Attempt to establish second link on <%s> to %s\n",
251 b_ptr->name, addr_string);
255 l_ptr = kzalloc(sizeof(*l_ptr), GFP_ATOMIC);
257 pr_warn("Link creation failed, no memory\n");
260 kref_init(&l_ptr->ref);
262 if_name = strchr(b_ptr->name, ':') + 1;
263 sprintf(l_ptr->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
264 tipc_zone(tn->own_addr), tipc_cluster(tn->own_addr),
265 tipc_node(tn->own_addr),
267 tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
268 /* note: peer i/f name is updated by reset/activate message */
269 memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
270 l_ptr->owner = n_ptr;
271 l_ptr->peer_session = INVALID_SESSION;
272 l_ptr->bearer_id = b_ptr->identity;
273 link_set_supervision_props(l_ptr, b_ptr->tolerance);
274 l_ptr->state = RESET_UNKNOWN;
276 l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
278 tipc_msg_init(tn->own_addr, msg, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE,
280 msg_set_size(msg, sizeof(l_ptr->proto_msg));
281 msg_set_session(msg, (tn->random & 0xffff));
282 msg_set_bearer_id(msg, b_ptr->identity);
283 strcpy((char *)msg_data(msg), if_name);
284 l_ptr->net_plane = b_ptr->net_plane;
285 l_ptr->advertised_mtu = b_ptr->mtu;
286 l_ptr->mtu = l_ptr->advertised_mtu;
287 l_ptr->priority = b_ptr->priority;
288 tipc_link_set_queue_limits(l_ptr, b_ptr->window);
290 __skb_queue_head_init(&l_ptr->transmq);
291 __skb_queue_head_init(&l_ptr->backlogq);
292 __skb_queue_head_init(&l_ptr->deferdq);
293 skb_queue_head_init(&l_ptr->wakeupq);
294 l_ptr->inputq = inputq;
295 l_ptr->namedq = namedq;
296 skb_queue_head_init(l_ptr->inputq);
297 link_reset_statistics(l_ptr);
298 tipc_node_attach_link(n_ptr, l_ptr);
299 setup_timer(&l_ptr->timer, link_timeout, (unsigned long)l_ptr);
300 link_state_event(l_ptr, STARTING_EVT);
306 * tipc_link_delete - Delete a link
307 * @l: link to be deleted
309 void tipc_link_delete(struct tipc_link *l)
312 if (del_timer(&l->timer))
314 l->flags |= LINK_STOPPED;
315 /* Delete link now, or when timer is finished: */
316 tipc_link_reset_fragments(l);
317 tipc_node_detach_link(l->owner, l);
321 void tipc_link_delete_list(struct net *net, unsigned int bearer_id)
323 struct tipc_net *tn = net_generic(net, tipc_net_id);
324 struct tipc_link *link;
325 struct tipc_node *node;
328 list_for_each_entry_rcu(node, &tn->node_list, list) {
329 tipc_node_lock(node);
330 link = node->links[bearer_id].link;
332 tipc_link_delete(link);
333 tipc_node_unlock(node);
339 * link_schedule_user - schedule a message sender for wakeup after congestion
340 * @link: congested link
341 * @list: message that was attempted sent
342 * Create pseudo msg to send back to user when congestion abates
343 * Does not consume buffer list
345 static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list)
347 struct tipc_msg *msg = buf_msg(skb_peek(list));
348 int imp = msg_importance(msg);
349 u32 oport = msg_origport(msg);
350 u32 addr = link_own_addr(link);
353 /* This really cannot happen... */
354 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
355 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
358 /* Non-blocking sender: */
359 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending)
362 /* Create and schedule wakeup pseudo message */
363 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
364 addr, addr, oport, 0, 0);
367 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list);
368 TIPC_SKB_CB(skb)->chain_imp = imp;
369 skb_queue_tail(&link->wakeupq, skb);
370 link->stats.link_congs++;
375 * link_prepare_wakeup - prepare users for wakeup after congestion
376 * @link: congested link
377 * Move a number of waiting users, as permitted by available space in
378 * the send queue, from link wait queue to node wait queue for wakeup
380 void link_prepare_wakeup(struct tipc_link *l)
382 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
384 struct sk_buff *skb, *tmp;
386 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
387 imp = TIPC_SKB_CB(skb)->chain_imp;
388 lim = l->window + l->backlog[imp].limit;
389 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
390 if ((pnd[imp] + l->backlog[imp].len) >= lim)
392 skb_unlink(skb, &l->wakeupq);
393 skb_queue_tail(l->inputq, skb);
394 l->owner->inputq = l->inputq;
395 l->owner->action_flags |= TIPC_MSG_EVT;
400 * tipc_link_reset_fragments - purge link's inbound message fragments queue
401 * @l_ptr: pointer to link
403 void tipc_link_reset_fragments(struct tipc_link *l_ptr)
405 kfree_skb(l_ptr->reasm_buf);
406 l_ptr->reasm_buf = NULL;
409 void tipc_link_purge_backlog(struct tipc_link *l)
411 __skb_queue_purge(&l->backlogq);
412 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
413 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
414 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
415 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
416 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
420 * tipc_link_purge_queues - purge all pkt queues associated with link
421 * @l_ptr: pointer to link
423 void tipc_link_purge_queues(struct tipc_link *l_ptr)
425 __skb_queue_purge(&l_ptr->deferdq);
426 __skb_queue_purge(&l_ptr->transmq);
427 tipc_link_purge_backlog(l_ptr);
428 tipc_link_reset_fragments(l_ptr);
431 void tipc_link_reset(struct tipc_link *l_ptr)
433 u32 prev_state = l_ptr->state;
434 int was_active_link = tipc_link_is_active(l_ptr);
435 struct tipc_node *owner = l_ptr->owner;
436 struct tipc_link *pl = tipc_parallel_link(l_ptr);
438 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
440 /* Link is down, accept any session */
441 l_ptr->peer_session = INVALID_SESSION;
443 /* Prepare for renewed mtu size negotiation */
444 l_ptr->mtu = l_ptr->advertised_mtu;
446 l_ptr->state = RESET_UNKNOWN;
448 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
451 tipc_node_link_down(l_ptr->owner, l_ptr->bearer_id);
452 tipc_bearer_remove_dest(owner->net, l_ptr->bearer_id, l_ptr->addr);
454 if (was_active_link && tipc_node_is_up(l_ptr->owner) && (pl != l_ptr)) {
455 l_ptr->flags |= LINK_FAILINGOVER;
456 l_ptr->failover_checkpt = l_ptr->rcv_nxt;
457 pl->failover_pkts = FIRST_FAILOVER;
458 pl->failover_checkpt = l_ptr->rcv_nxt;
459 pl->failover_skb = l_ptr->reasm_buf;
461 kfree_skb(l_ptr->reasm_buf);
463 /* Clean up all queues, except inputq: */
464 __skb_queue_purge(&l_ptr->transmq);
465 __skb_queue_purge(&l_ptr->deferdq);
467 owner->inputq = l_ptr->inputq;
468 skb_queue_splice_init(&l_ptr->wakeupq, owner->inputq);
469 if (!skb_queue_empty(owner->inputq))
470 owner->action_flags |= TIPC_MSG_EVT;
471 tipc_link_purge_backlog(l_ptr);
472 l_ptr->reasm_buf = NULL;
473 l_ptr->rcv_unacked = 0;
475 l_ptr->silent_intv_cnt = 0;
476 l_ptr->stale_count = 0;
477 link_reset_statistics(l_ptr);
480 static void link_activate(struct tipc_link *link)
482 struct tipc_node *node = link->owner;
485 link->stats.recv_info = 1;
486 link->silent_intv_cnt = 0;
487 tipc_node_link_up(node, link->bearer_id);
488 tipc_bearer_add_dest(node->net, link->bearer_id, link->addr);
492 * link_state_event - link finite state machine
493 * @l_ptr: pointer to link
494 * @event: state machine event to process
496 static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
498 struct tipc_link *other;
499 unsigned long timer_intv = l_ptr->keepalive_intv;
501 if (l_ptr->flags & LINK_STOPPED)
504 if (!(l_ptr->flags & LINK_STARTED) && (event != STARTING_EVT))
505 return; /* Not yet. */
507 if (l_ptr->flags & LINK_FAILINGOVER)
510 switch (l_ptr->state) {
511 case WORKING_WORKING:
513 case TRAFFIC_MSG_EVT:
515 l_ptr->silent_intv_cnt = 0;
518 if (!l_ptr->silent_intv_cnt) {
519 if (tipc_bclink_acks_missing(l_ptr->owner))
520 tipc_link_proto_xmit(l_ptr, STATE_MSG,
524 l_ptr->state = WORKING_UNKNOWN;
525 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0);
528 pr_debug("%s<%s>, requested by peer\n",
529 link_rst_msg, l_ptr->name);
530 tipc_link_reset(l_ptr);
531 l_ptr->state = RESET_RESET;
532 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
536 pr_debug("%s%u in WW state\n", link_unk_evt, event);
539 case WORKING_UNKNOWN:
541 case TRAFFIC_MSG_EVT:
543 l_ptr->state = WORKING_WORKING;
544 l_ptr->silent_intv_cnt = 0;
547 pr_debug("%s<%s>, requested by peer while probing\n",
548 link_rst_msg, l_ptr->name);
549 tipc_link_reset(l_ptr);
550 l_ptr->state = RESET_RESET;
551 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
555 if (!l_ptr->silent_intv_cnt) {
556 l_ptr->state = WORKING_WORKING;
557 if (tipc_bclink_acks_missing(l_ptr->owner))
558 tipc_link_proto_xmit(l_ptr, STATE_MSG,
560 } else if (l_ptr->silent_intv_cnt <
561 l_ptr->abort_limit) {
562 tipc_link_proto_xmit(l_ptr, STATE_MSG,
564 } else { /* Link has failed */
565 pr_debug("%s<%s>, peer not responding\n",
566 link_rst_msg, l_ptr->name);
567 tipc_link_reset(l_ptr);
568 l_ptr->state = RESET_UNKNOWN;
569 tipc_link_proto_xmit(l_ptr, RESET_MSG,
574 pr_err("%s%u in WU state\n", link_unk_evt, event);
579 case TRAFFIC_MSG_EVT:
582 other = node_active_link(l_ptr->owner, 0);
583 if (other && link_working_unknown(other))
585 l_ptr->state = WORKING_WORKING;
586 link_activate(l_ptr);
587 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0);
588 if (l_ptr->owner->working_links == 1)
589 tipc_link_sync_xmit(l_ptr);
592 l_ptr->state = RESET_RESET;
593 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
597 l_ptr->flags |= LINK_STARTED;
598 link_set_timer(l_ptr, timer_intv);
601 tipc_link_proto_xmit(l_ptr, RESET_MSG, 0, 0, 0, 0);
604 pr_err("%s%u in RU state\n", link_unk_evt, event);
609 case TRAFFIC_MSG_EVT:
611 other = node_active_link(l_ptr->owner, 0);
612 if (other && link_working_unknown(other))
614 l_ptr->state = WORKING_WORKING;
615 link_activate(l_ptr);
616 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0);
617 if (l_ptr->owner->working_links == 1)
618 tipc_link_sync_xmit(l_ptr);
623 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
627 pr_err("%s%u in RR state\n", link_unk_evt, event);
631 pr_err("Unknown link state %u/%u\n", l_ptr->state, event);
636 * __tipc_link_xmit(): same as tipc_link_xmit, but destlink is known & locked
638 * @list: chain of buffers containing message
640 * Consumes the buffer chain, except when returning an error code,
641 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
642 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
644 int __tipc_link_xmit(struct net *net, struct tipc_link *link,
645 struct sk_buff_head *list)
647 struct tipc_msg *msg = buf_msg(skb_peek(list));
648 unsigned int maxwin = link->window;
649 unsigned int i, imp = msg_importance(msg);
650 uint mtu = link->mtu;
651 u16 ack = mod(link->rcv_nxt - 1);
652 u16 seqno = link->snd_nxt;
653 u16 bc_last_in = link->owner->bclink.last_in;
654 struct tipc_media_addr *addr = &link->media_addr;
655 struct sk_buff_head *transmq = &link->transmq;
656 struct sk_buff_head *backlogq = &link->backlogq;
657 struct sk_buff *skb, *bskb;
659 /* Match msg importance against this and all higher backlog limits: */
660 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
661 if (unlikely(link->backlog[i].len >= link->backlog[i].limit))
662 return link_schedule_user(link, list);
664 if (unlikely(msg_size(msg) > mtu))
667 /* Prepare each packet for sending, and add to relevant queue: */
668 while (skb_queue_len(list)) {
669 skb = skb_peek(list);
671 msg_set_seqno(msg, seqno);
672 msg_set_ack(msg, ack);
673 msg_set_bcast_ack(msg, bc_last_in);
675 if (likely(skb_queue_len(transmq) < maxwin)) {
677 __skb_queue_tail(transmq, skb);
678 tipc_bearer_send(net, link->bearer_id, skb, addr);
679 link->rcv_unacked = 0;
683 if (tipc_msg_bundle(skb_peek_tail(backlogq), msg, mtu)) {
684 kfree_skb(__skb_dequeue(list));
685 link->stats.sent_bundled++;
688 if (tipc_msg_make_bundle(&bskb, msg, mtu, link->addr)) {
689 kfree_skb(__skb_dequeue(list));
690 __skb_queue_tail(backlogq, bskb);
691 link->backlog[msg_importance(buf_msg(bskb))].len++;
692 link->stats.sent_bundled++;
693 link->stats.sent_bundles++;
696 link->backlog[imp].len += skb_queue_len(list);
697 skb_queue_splice_tail_init(list, backlogq);
699 link->snd_nxt = seqno;
704 * tipc_link_xmit(): enqueue buffer list according to queue situation
706 * @list: chain of buffers containing message
707 * @xmitq: returned list of packets to be sent by caller
709 * Consumes the buffer chain, except when returning -ELINKCONG,
710 * since the caller then may want to make more send attempts.
711 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
712 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
714 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
715 struct sk_buff_head *xmitq)
717 struct tipc_msg *hdr = buf_msg(skb_peek(list));
718 unsigned int maxwin = l->window;
719 unsigned int i, imp = msg_importance(hdr);
720 unsigned int mtu = l->mtu;
721 u16 ack = l->rcv_nxt - 1;
722 u16 seqno = l->snd_nxt;
723 u16 bc_last_in = l->owner->bclink.last_in;
724 struct sk_buff_head *transmq = &l->transmq;
725 struct sk_buff_head *backlogq = &l->backlogq;
726 struct sk_buff *skb, *_skb, *bskb;
728 /* Match msg importance against this and all higher backlog limits: */
729 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
730 if (unlikely(l->backlog[i].len >= l->backlog[i].limit))
731 return link_schedule_user(l, list);
733 if (unlikely(msg_size(hdr) > mtu))
736 /* Prepare each packet for sending, and add to relevant queue: */
737 while (skb_queue_len(list)) {
738 skb = skb_peek(list);
740 msg_set_seqno(hdr, seqno);
741 msg_set_ack(hdr, ack);
742 msg_set_bcast_ack(hdr, bc_last_in);
744 if (likely(skb_queue_len(transmq) < maxwin)) {
745 _skb = skb_clone(skb, GFP_ATOMIC);
749 __skb_queue_tail(transmq, skb);
750 __skb_queue_tail(xmitq, _skb);
755 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) {
756 kfree_skb(__skb_dequeue(list));
757 l->stats.sent_bundled++;
760 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) {
761 kfree_skb(__skb_dequeue(list));
762 __skb_queue_tail(backlogq, bskb);
763 l->backlog[msg_importance(buf_msg(bskb))].len++;
764 l->stats.sent_bundled++;
765 l->stats.sent_bundles++;
768 l->backlog[imp].len += skb_queue_len(list);
769 skb_queue_splice_tail_init(list, backlogq);
775 static void skb2list(struct sk_buff *skb, struct sk_buff_head *list)
777 skb_queue_head_init(list);
778 __skb_queue_tail(list, skb);
781 static int __tipc_link_xmit_skb(struct tipc_link *link, struct sk_buff *skb)
783 struct sk_buff_head head;
785 skb2list(skb, &head);
786 return __tipc_link_xmit(link->owner->net, link, &head);
790 * tipc_link_sync_xmit - synchronize broadcast link endpoints.
792 * Give a newly added peer node the sequence number where it should
793 * start receiving and acking broadcast packets.
795 * Called with node locked
797 static void tipc_link_sync_xmit(struct tipc_link *link)
800 struct tipc_msg *msg;
802 skb = tipc_buf_acquire(INT_H_SIZE);
807 tipc_msg_init(link_own_addr(link), msg, BCAST_PROTOCOL, STATE_MSG,
808 INT_H_SIZE, link->addr);
809 msg_set_last_bcast(msg, link->owner->bclink.acked);
810 __tipc_link_xmit_skb(link, skb);
814 * tipc_link_sync_rcv - synchronize broadcast link endpoints.
815 * Receive the sequence number where we should start receiving and
816 * acking broadcast packets from a newly added peer node, and open
817 * up for reception of such packets.
819 * Called with node locked
821 static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf)
823 struct tipc_msg *msg = buf_msg(buf);
825 n->bclink.last_sent = n->bclink.last_in = msg_last_bcast(msg);
826 n->bclink.recv_permitted = true;
831 * tipc_link_push_packets - push unsent packets to bearer
833 * Push out the unsent messages of a link where congestion
834 * has abated. Node is locked.
836 * Called with node locked
838 void tipc_link_push_packets(struct tipc_link *link)
841 struct tipc_msg *msg;
842 u16 seqno = link->snd_nxt;
843 u16 ack = mod(link->rcv_nxt - 1);
845 while (skb_queue_len(&link->transmq) < link->window) {
846 skb = __skb_dequeue(&link->backlogq);
850 link->backlog[msg_importance(msg)].len--;
851 msg_set_ack(msg, ack);
852 msg_set_seqno(msg, seqno);
853 seqno = mod(seqno + 1);
854 msg_set_bcast_ack(msg, link->owner->bclink.last_in);
855 link->rcv_unacked = 0;
856 __skb_queue_tail(&link->transmq, skb);
857 tipc_bearer_send(link->owner->net, link->bearer_id,
858 skb, &link->media_addr);
860 link->snd_nxt = seqno;
863 void tipc_link_reset_all(struct tipc_node *node)
865 char addr_string[16];
868 tipc_node_lock(node);
870 pr_warn("Resetting all links to %s\n",
871 tipc_addr_string_fill(addr_string, node->addr));
873 for (i = 0; i < MAX_BEARERS; i++) {
874 if (node->links[i].link) {
875 link_print(node->links[i].link, "Resetting link\n");
876 tipc_link_reset(node->links[i].link);
880 tipc_node_unlock(node);
883 static void link_retransmit_failure(struct tipc_link *l_ptr,
886 struct tipc_msg *msg = buf_msg(buf);
887 struct net *net = l_ptr->owner->net;
889 pr_warn("Retransmission failure on link <%s>\n", l_ptr->name);
892 /* Handle failure on standard link */
893 link_print(l_ptr, "Resetting link\n");
894 tipc_link_reset(l_ptr);
897 /* Handle failure on broadcast link */
898 struct tipc_node *n_ptr;
899 char addr_string[16];
901 pr_info("Msg seq number: %u, ", msg_seqno(msg));
902 pr_cont("Outstanding acks: %lu\n",
903 (unsigned long) TIPC_SKB_CB(buf)->handle);
905 n_ptr = tipc_bclink_retransmit_to(net);
907 tipc_addr_string_fill(addr_string, n_ptr->addr);
908 pr_info("Broadcast link info for %s\n", addr_string);
909 pr_info("Reception permitted: %d, Acked: %u\n",
910 n_ptr->bclink.recv_permitted,
911 n_ptr->bclink.acked);
912 pr_info("Last in: %u, Oos state: %u, Last sent: %u\n",
913 n_ptr->bclink.last_in,
914 n_ptr->bclink.oos_state,
915 n_ptr->bclink.last_sent);
917 n_ptr->action_flags |= TIPC_BCAST_RESET;
918 l_ptr->stale_count = 0;
922 void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *skb,
925 struct tipc_msg *msg;
932 /* Detect repeated retransmit failures */
933 if (l_ptr->last_retransm == msg_seqno(msg)) {
934 if (++l_ptr->stale_count > 100) {
935 link_retransmit_failure(l_ptr, skb);
939 l_ptr->last_retransm = msg_seqno(msg);
940 l_ptr->stale_count = 1;
943 skb_queue_walk_from(&l_ptr->transmq, skb) {
947 msg_set_ack(msg, mod(l_ptr->rcv_nxt - 1));
948 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
949 tipc_bearer_send(l_ptr->owner->net, l_ptr->bearer_id, skb,
952 l_ptr->stats.retransmitted++;
956 /* link_synch(): check if all packets arrived before the synch
957 * point have been consumed
958 * Returns true if the parallel links are synched, otherwise false
960 static bool link_synch(struct tipc_link *l)
962 unsigned int post_synch;
963 struct tipc_link *pl;
965 pl = tipc_parallel_link(l);
969 /* Was last pre-synch packet added to input queue ? */
970 if (less_eq(pl->rcv_nxt, l->synch_point))
973 /* Is it still in the input queue ? */
974 post_synch = mod(pl->rcv_nxt - l->synch_point) - 1;
975 if (skb_queue_len(pl->inputq) > post_synch)
978 l->flags &= ~LINK_SYNCHING;
982 static void link_retrieve_defq(struct tipc_link *link,
983 struct sk_buff_head *list)
987 if (skb_queue_empty(&link->deferdq))
990 seq_no = buf_seqno(skb_peek(&link->deferdq));
991 if (seq_no == link->rcv_nxt)
992 skb_queue_splice_tail_init(&link->deferdq, list);
996 * tipc_rcv - process TIPC packets/messages arriving from off-node
997 * @net: the applicable net namespace
999 * @b_ptr: pointer to bearer message arrived on
1001 * Invoked with no locks held. Bearer pointer must point to a valid bearer
1002 * structure (i.e. cannot be NULL), but bearer can be inactive.
1004 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b_ptr)
1006 struct tipc_net *tn = net_generic(net, tipc_net_id);
1007 struct sk_buff_head head;
1008 struct tipc_node *n_ptr;
1009 struct tipc_link *l_ptr;
1010 struct sk_buff *skb1, *tmp;
1011 struct tipc_msg *msg;
1016 skb2list(skb, &head);
1018 while ((skb = __skb_dequeue(&head))) {
1019 /* Ensure message is well-formed */
1020 if (unlikely(!tipc_msg_validate(skb)))
1023 /* Handle arrival of a non-unicast link message */
1025 if (unlikely(msg_non_seq(msg))) {
1026 if (msg_user(msg) == LINK_CONFIG)
1027 tipc_disc_rcv(net, skb, b_ptr);
1029 tipc_bclink_rcv(net, skb);
1033 /* Discard unicast link messages destined for another node */
1034 if (unlikely(!msg_short(msg) &&
1035 (msg_destnode(msg) != tn->own_addr)))
1038 /* Locate neighboring node that sent message */
1039 n_ptr = tipc_node_find(net, msg_prevnode(msg));
1040 if (unlikely(!n_ptr))
1043 tipc_node_lock(n_ptr);
1044 /* Locate unicast link endpoint that should handle message */
1045 l_ptr = n_ptr->links[b_ptr->identity].link;
1046 if (unlikely(!l_ptr))
1049 /* Verify that communication with node is currently allowed */
1050 if ((n_ptr->action_flags & TIPC_WAIT_PEER_LINKS_DOWN) &&
1051 msg_user(msg) == LINK_PROTOCOL &&
1052 (msg_type(msg) == RESET_MSG ||
1053 msg_type(msg) == ACTIVATE_MSG) &&
1054 !msg_redundant_link(msg))
1055 n_ptr->action_flags &= ~TIPC_WAIT_PEER_LINKS_DOWN;
1057 if (tipc_node_blocked(n_ptr))
1060 /* Validate message sequence number info */
1061 seq_no = msg_seqno(msg);
1062 ackd = msg_ack(msg);
1064 /* Release acked messages */
1065 if (unlikely(n_ptr->bclink.acked != msg_bcast_ack(msg)))
1066 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1069 skb_queue_walk_safe(&l_ptr->transmq, skb1, tmp) {
1070 if (more(buf_seqno(skb1), ackd))
1072 __skb_unlink(skb1, &l_ptr->transmq);
1077 /* Try sending any messages link endpoint has pending */
1078 if (unlikely(skb_queue_len(&l_ptr->backlogq)))
1079 tipc_link_push_packets(l_ptr);
1081 if (released && !skb_queue_empty(&l_ptr->wakeupq))
1082 link_prepare_wakeup(l_ptr);
1084 /* Process the incoming packet */
1085 if (unlikely(!link_working_working(l_ptr))) {
1086 if (msg_user(msg) == LINK_PROTOCOL) {
1087 tipc_link_proto_rcv(l_ptr, skb);
1088 link_retrieve_defq(l_ptr, &head);
1093 /* Traffic message. Conditionally activate link */
1094 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1096 if (link_working_working(l_ptr)) {
1097 /* Re-insert buffer in front of queue */
1098 __skb_queue_head(&head, skb);
1105 /* Link is now in state WORKING_WORKING */
1106 if (unlikely(seq_no != l_ptr->rcv_nxt)) {
1107 link_handle_out_of_seq_msg(l_ptr, skb);
1108 link_retrieve_defq(l_ptr, &head);
1112 l_ptr->silent_intv_cnt = 0;
1114 /* Synchronize with parallel link if applicable */
1115 if (unlikely((l_ptr->flags & LINK_SYNCHING) && !msg_dup(msg))) {
1116 if (!link_synch(l_ptr))
1120 if (unlikely(!skb_queue_empty(&l_ptr->deferdq)))
1121 link_retrieve_defq(l_ptr, &head);
1122 if (unlikely(++l_ptr->rcv_unacked >= TIPC_MIN_LINK_WIN)) {
1123 l_ptr->stats.sent_acks++;
1124 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0);
1126 tipc_link_input(l_ptr, skb);
1129 tipc_node_unlock(n_ptr);
1130 tipc_node_put(n_ptr);
1137 /* tipc_data_input - deliver data and name distr msgs to upper layer
1139 * Consumes buffer if message is of right type
1140 * Node lock must be held
1142 static bool tipc_data_input(struct tipc_link *link, struct sk_buff *skb)
1144 struct tipc_node *node = link->owner;
1145 struct tipc_msg *msg = buf_msg(skb);
1146 u32 dport = msg_destport(msg);
1148 switch (msg_user(msg)) {
1149 case TIPC_LOW_IMPORTANCE:
1150 case TIPC_MEDIUM_IMPORTANCE:
1151 case TIPC_HIGH_IMPORTANCE:
1152 case TIPC_CRITICAL_IMPORTANCE:
1154 if (tipc_skb_queue_tail(link->inputq, skb, dport)) {
1155 node->inputq = link->inputq;
1156 node->action_flags |= TIPC_MSG_EVT;
1159 case NAME_DISTRIBUTOR:
1160 node->bclink.recv_permitted = true;
1161 node->namedq = link->namedq;
1162 skb_queue_tail(link->namedq, skb);
1163 if (skb_queue_len(link->namedq) == 1)
1164 node->action_flags |= TIPC_NAMED_MSG_EVT;
1167 case TUNNEL_PROTOCOL:
1168 case MSG_FRAGMENTER:
1169 case BCAST_PROTOCOL:
1172 pr_warn("Dropping received illegal msg type\n");
1178 /* tipc_link_input - process packet that has passed link protocol check
1181 * Node lock must be held
1183 static void tipc_link_input(struct tipc_link *link, struct sk_buff *skb)
1185 struct tipc_node *node = link->owner;
1186 struct tipc_msg *msg = buf_msg(skb);
1187 struct sk_buff *iskb;
1190 if (likely(tipc_data_input(link, skb)))
1193 switch (msg_user(msg)) {
1194 case TUNNEL_PROTOCOL:
1196 link->flags |= LINK_SYNCHING;
1197 link->synch_point = msg_seqno(msg_get_wrapped(msg));
1201 if (!tipc_link_failover_rcv(link, &skb))
1203 if (msg_user(buf_msg(skb)) != MSG_BUNDLER) {
1204 tipc_data_input(link, skb);
1208 link->stats.recv_bundles++;
1209 link->stats.recv_bundled += msg_msgcnt(msg);
1211 while (tipc_msg_extract(skb, &iskb, &pos))
1212 tipc_data_input(link, iskb);
1214 case MSG_FRAGMENTER:
1215 link->stats.recv_fragments++;
1216 if (tipc_buf_append(&link->reasm_buf, &skb)) {
1217 link->stats.recv_fragmented++;
1218 tipc_data_input(link, skb);
1219 } else if (!link->reasm_buf) {
1220 tipc_link_reset(link);
1223 case BCAST_PROTOCOL:
1224 tipc_link_sync_rcv(node, skb);
1232 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1234 * Returns increase in queue length (i.e. 0 or 1)
1236 u32 tipc_link_defer_pkt(struct sk_buff_head *list, struct sk_buff *skb)
1238 struct sk_buff *skb1;
1239 u16 seq_no = buf_seqno(skb);
1242 if (skb_queue_empty(list)) {
1243 __skb_queue_tail(list, skb);
1248 if (less(buf_seqno(skb_peek_tail(list)), seq_no)) {
1249 __skb_queue_tail(list, skb);
1253 /* Locate insertion point in queue, then insert; discard if duplicate */
1254 skb_queue_walk(list, skb1) {
1255 u16 curr_seqno = buf_seqno(skb1);
1257 if (seq_no == curr_seqno) {
1262 if (less(seq_no, curr_seqno))
1266 __skb_queue_before(list, skb1, skb);
1271 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1273 static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
1274 struct sk_buff *buf)
1276 u32 seq_no = buf_seqno(buf);
1278 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1279 tipc_link_proto_rcv(l_ptr, buf);
1283 /* Record OOS packet arrival */
1284 l_ptr->silent_intv_cnt = 0;
1287 * Discard packet if a duplicate; otherwise add it to deferred queue
1288 * and notify peer of gap as per protocol specification
1290 if (less(seq_no, l_ptr->rcv_nxt)) {
1291 l_ptr->stats.duplicates++;
1296 if (tipc_link_defer_pkt(&l_ptr->deferdq, buf)) {
1297 l_ptr->stats.deferred_recv++;
1298 if ((skb_queue_len(&l_ptr->deferdq) % TIPC_MIN_LINK_WIN) == 1)
1299 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0);
1301 l_ptr->stats.duplicates++;
1306 * Send protocol message to the other endpoint.
1308 void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg,
1309 u32 gap, u32 tolerance, u32 priority)
1311 struct sk_buff *buf = NULL;
1312 struct tipc_msg *msg = l_ptr->pmsg;
1313 u32 msg_size = sizeof(l_ptr->proto_msg);
1317 /* Don't send protocol message during link failover */
1318 if (l_ptr->flags & LINK_FAILINGOVER)
1321 /* Abort non-RESET send if communication with node is prohibited */
1322 if ((tipc_node_blocked(l_ptr->owner)) && (msg_typ != RESET_MSG))
1325 /* Create protocol message with "out-of-sequence" sequence number */
1326 msg_set_type(msg, msg_typ);
1327 msg_set_net_plane(msg, l_ptr->net_plane);
1328 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1329 msg_set_last_bcast(msg, tipc_bclink_get_last_sent(l_ptr->owner->net));
1331 if (msg_typ == STATE_MSG) {
1332 u16 next_sent = l_ptr->snd_nxt;
1334 if (!tipc_link_is_up(l_ptr))
1336 msg_set_next_sent(msg, next_sent);
1337 if (!skb_queue_empty(&l_ptr->deferdq)) {
1338 last_rcv = buf_seqno(skb_peek(&l_ptr->deferdq));
1339 gap = mod(last_rcv - l_ptr->rcv_nxt);
1341 msg_set_seq_gap(msg, gap);
1343 l_ptr->stats.sent_nacks++;
1344 msg_set_link_tolerance(msg, tolerance);
1345 msg_set_linkprio(msg, priority);
1346 msg_set_max_pkt(msg, l_ptr->mtu);
1347 msg_set_ack(msg, mod(l_ptr->rcv_nxt - 1));
1348 msg_set_probe(msg, probe_msg != 0);
1350 l_ptr->stats.sent_probes++;
1351 l_ptr->stats.sent_states++;
1352 } else { /* RESET_MSG or ACTIVATE_MSG */
1353 msg_set_ack(msg, mod(l_ptr->failover_checkpt - 1));
1354 msg_set_seq_gap(msg, 0);
1355 msg_set_next_sent(msg, 1);
1356 msg_set_probe(msg, 0);
1357 msg_set_link_tolerance(msg, l_ptr->tolerance);
1358 msg_set_linkprio(msg, l_ptr->priority);
1359 msg_set_max_pkt(msg, l_ptr->advertised_mtu);
1362 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
1363 msg_set_redundant_link(msg, r_flag);
1364 msg_set_linkprio(msg, l_ptr->priority);
1365 msg_set_size(msg, msg_size);
1367 msg_set_seqno(msg, mod(l_ptr->snd_nxt + (0xffff / 2)));
1369 buf = tipc_buf_acquire(msg_size);
1373 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
1374 buf->priority = TC_PRIO_CONTROL;
1375 tipc_bearer_send(l_ptr->owner->net, l_ptr->bearer_id, buf,
1376 &l_ptr->media_addr);
1377 l_ptr->rcv_unacked = 0;
1382 * Receive protocol message :
1383 * Note that network plane id propagates through the network, and may
1384 * change at any time. The node with lowest address rules
1386 static void tipc_link_proto_rcv(struct tipc_link *l_ptr,
1387 struct sk_buff *buf)
1391 struct tipc_msg *msg = buf_msg(buf);
1393 if (l_ptr->flags & LINK_FAILINGOVER)
1396 if (l_ptr->net_plane != msg_net_plane(msg))
1397 if (link_own_addr(l_ptr) > msg_prevnode(msg))
1398 l_ptr->net_plane = msg_net_plane(msg);
1400 switch (msg_type(msg)) {
1403 if (!link_working_unknown(l_ptr) &&
1404 (l_ptr->peer_session != INVALID_SESSION)) {
1405 if (less_eq(msg_session(msg), l_ptr->peer_session))
1406 break; /* duplicate or old reset: ignore */
1409 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
1410 link_working_unknown(l_ptr))) {
1412 * peer has lost contact -- don't allow peer's links
1413 * to reactivate before we recognize loss & clean up
1415 l_ptr->owner->action_flags |= TIPC_WAIT_OWN_LINKS_DOWN;
1418 link_state_event(l_ptr, RESET_MSG);
1422 /* Update link settings according other endpoint's values */
1423 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
1425 msg_tol = msg_link_tolerance(msg);
1426 if (msg_tol > l_ptr->tolerance)
1427 link_set_supervision_props(l_ptr, msg_tol);
1429 if (msg_linkprio(msg) > l_ptr->priority)
1430 l_ptr->priority = msg_linkprio(msg);
1432 if (l_ptr->mtu > msg_max_pkt(msg))
1433 l_ptr->mtu = msg_max_pkt(msg);
1435 /* Synchronize broadcast link info, if not done previously */
1436 if (!tipc_node_is_up(l_ptr->owner)) {
1437 l_ptr->owner->bclink.last_sent =
1438 l_ptr->owner->bclink.last_in =
1439 msg_last_bcast(msg);
1440 l_ptr->owner->bclink.oos_state = 0;
1443 l_ptr->peer_session = msg_session(msg);
1444 l_ptr->peer_bearer_id = msg_bearer_id(msg);
1446 if (msg_type(msg) == ACTIVATE_MSG)
1447 link_state_event(l_ptr, ACTIVATE_MSG);
1451 msg_tol = msg_link_tolerance(msg);
1453 link_set_supervision_props(l_ptr, msg_tol);
1455 if (msg_linkprio(msg) &&
1456 (msg_linkprio(msg) != l_ptr->priority)) {
1457 pr_debug("%s<%s>, priority change %u->%u\n",
1458 link_rst_msg, l_ptr->name,
1459 l_ptr->priority, msg_linkprio(msg));
1460 l_ptr->priority = msg_linkprio(msg);
1461 tipc_link_reset(l_ptr); /* Enforce change to take effect */
1465 /* Record reception; force mismatch at next timeout: */
1466 l_ptr->silent_intv_cnt = 0;
1468 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1469 l_ptr->stats.recv_states++;
1470 if (link_reset_unknown(l_ptr))
1473 if (less_eq(l_ptr->rcv_nxt, msg_next_sent(msg)))
1474 rec_gap = mod(msg_next_sent(msg) - l_ptr->rcv_nxt);
1477 l_ptr->stats.recv_probes++;
1479 /* Protocol message before retransmits, reduce loss risk */
1480 if (l_ptr->owner->bclink.recv_permitted)
1481 tipc_bclink_update_link_state(l_ptr->owner,
1482 msg_last_bcast(msg));
1484 if (rec_gap || (msg_probe(msg))) {
1485 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0,
1488 if (msg_seq_gap(msg)) {
1489 l_ptr->stats.recv_nacks++;
1490 tipc_link_retransmit(l_ptr, skb_peek(&l_ptr->transmq),
1500 /* tipc_link_tunnel_xmit(): Tunnel one packet via a link belonging to
1501 * a different bearer. Owner node is locked.
1503 static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr,
1504 struct tipc_msg *tunnel_hdr,
1505 struct tipc_msg *msg,
1508 struct tipc_link *tunnel;
1509 struct sk_buff *skb;
1510 u32 length = msg_size(msg);
1512 tunnel = node_active_link(l_ptr->owner, selector & 1);
1513 if (!tipc_link_is_up(tunnel)) {
1514 pr_warn("%stunnel link no longer available\n", link_co_err);
1517 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
1518 skb = tipc_buf_acquire(length + INT_H_SIZE);
1520 pr_warn("%sunable to send tunnel msg\n", link_co_err);
1523 skb_copy_to_linear_data(skb, tunnel_hdr, INT_H_SIZE);
1524 skb_copy_to_linear_data_offset(skb, INT_H_SIZE, msg, length);
1525 __tipc_link_xmit_skb(tunnel, skb);
1529 /* tipc_link_failover_send_queue(): A link has gone down, but a second
1530 * link is still active. We can do failover. Tunnel the failing link's
1531 * whole send queue via the remaining link. This way, we don't lose
1532 * any packets, and sequence order is preserved for subsequent traffic
1533 * sent over the remaining link. Owner node is locked.
1535 void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
1538 struct tipc_link *tunnel = node_active_link(l_ptr->owner, 0);
1539 struct tipc_msg tunnel_hdr;
1540 struct sk_buff *skb;
1546 tipc_msg_init(link_own_addr(l_ptr), &tunnel_hdr, TUNNEL_PROTOCOL,
1547 FAILOVER_MSG, INT_H_SIZE, l_ptr->addr);
1549 skb_queue_walk(&l_ptr->backlogq, skb) {
1550 msg_set_seqno(buf_msg(skb), l_ptr->snd_nxt);
1551 l_ptr->snd_nxt = mod(l_ptr->snd_nxt + 1);
1553 skb_queue_splice_tail_init(&l_ptr->backlogq, &l_ptr->transmq);
1554 tipc_link_purge_backlog(l_ptr);
1555 msgcount = skb_queue_len(&l_ptr->transmq);
1556 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
1557 msg_set_msgcnt(&tunnel_hdr, msgcount);
1559 if (skb_queue_empty(&l_ptr->transmq)) {
1560 skb = tipc_buf_acquire(INT_H_SIZE);
1562 skb_copy_to_linear_data(skb, &tunnel_hdr, INT_H_SIZE);
1563 msg_set_size(&tunnel_hdr, INT_H_SIZE);
1564 __tipc_link_xmit_skb(tunnel, skb);
1566 pr_warn("%sunable to send changeover msg\n",
1572 split_bundles = (node_active_link(l_ptr->owner, 0) !=
1573 node_active_link(l_ptr->owner, 0));
1575 skb_queue_walk(&l_ptr->transmq, skb) {
1576 struct tipc_msg *msg = buf_msg(skb);
1578 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
1579 struct tipc_msg *m = msg_get_wrapped(msg);
1580 unchar *pos = (unchar *)m;
1582 msgcount = msg_msgcnt(msg);
1583 while (msgcount--) {
1584 msg_set_seqno(m, msg_seqno(msg));
1585 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, m,
1586 msg_link_selector(m));
1587 pos += align(msg_size(m));
1588 m = (struct tipc_msg *)pos;
1591 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, msg,
1592 msg_link_selector(msg));
1597 /* tipc_link_dup_queue_xmit(): A second link has become active. Tunnel a
1598 * duplicate of the first link's send queue via the new link. This way, we
1599 * are guaranteed that currently queued packets from a socket are delivered
1600 * before future traffic from the same socket, even if this is using the
1601 * new link. The last arriving copy of each duplicate packet is dropped at
1602 * the receiving end by the regular protocol check, so packet cardinality
1603 * and sequence order is preserved per sender/receiver socket pair.
1604 * Owner node is locked.
1606 void tipc_link_dup_queue_xmit(struct tipc_link *link,
1607 struct tipc_link *tnl)
1609 struct sk_buff *skb;
1610 struct tipc_msg tnl_hdr;
1611 struct sk_buff_head *queue = &link->transmq;
1615 tipc_msg_init(link_own_addr(link), &tnl_hdr, TUNNEL_PROTOCOL,
1616 SYNCH_MSG, INT_H_SIZE, link->addr);
1617 mcnt = skb_queue_len(&link->transmq) + skb_queue_len(&link->backlogq);
1618 msg_set_msgcnt(&tnl_hdr, mcnt);
1619 msg_set_bearer_id(&tnl_hdr, link->peer_bearer_id);
1622 skb_queue_walk(queue, skb) {
1623 struct sk_buff *outskb;
1624 struct tipc_msg *msg = buf_msg(skb);
1625 u32 len = msg_size(msg);
1627 msg_set_ack(msg, mod(link->rcv_nxt - 1));
1628 msg_set_bcast_ack(msg, link->owner->bclink.last_in);
1629 msg_set_size(&tnl_hdr, len + INT_H_SIZE);
1630 outskb = tipc_buf_acquire(len + INT_H_SIZE);
1631 if (outskb == NULL) {
1632 pr_warn("%sunable to send duplicate msg\n",
1636 skb_copy_to_linear_data(outskb, &tnl_hdr, INT_H_SIZE);
1637 skb_copy_to_linear_data_offset(outskb, INT_H_SIZE,
1639 __tipc_link_xmit_skb(tnl, outskb);
1640 if (!tipc_link_is_up(link))
1643 if (queue == &link->backlogq)
1645 seqno = link->snd_nxt;
1646 skb_queue_walk(&link->backlogq, skb) {
1647 msg_set_seqno(buf_msg(skb), seqno);
1648 seqno = mod(seqno + 1);
1650 queue = &link->backlogq;
1654 /* tipc_link_failover_rcv(): Receive a tunnelled FAILOVER_MSG packet
1655 * Owner node is locked.
1657 static bool tipc_link_failover_rcv(struct tipc_link *link,
1658 struct sk_buff **skb)
1660 struct tipc_msg *msg = buf_msg(*skb);
1661 struct sk_buff *iskb = NULL;
1662 struct tipc_link *pl = NULL;
1663 int bearer_id = msg_bearer_id(msg);
1666 if (msg_type(msg) != FAILOVER_MSG) {
1667 pr_warn("%sunknown tunnel pkt received\n", link_co_err);
1670 if (bearer_id >= MAX_BEARERS)
1673 if (bearer_id == link->bearer_id)
1676 pl = link->owner->links[bearer_id].link;
1677 if (pl && tipc_link_is_up(pl))
1678 tipc_link_reset(pl);
1680 if (link->failover_pkts == FIRST_FAILOVER)
1681 link->failover_pkts = msg_msgcnt(msg);
1683 /* Should we expect an inner packet? */
1684 if (!link->failover_pkts)
1687 if (!tipc_msg_extract(*skb, &iskb, &pos)) {
1688 pr_warn("%sno inner failover pkt\n", link_co_err);
1692 link->failover_pkts--;
1695 /* Was this packet already delivered? */
1696 if (less(buf_seqno(iskb), link->failover_checkpt)) {
1701 if (msg_user(buf_msg(iskb)) == MSG_FRAGMENTER) {
1702 link->stats.recv_fragments++;
1703 tipc_buf_append(&link->failover_skb, &iskb);
1706 if (!link->failover_pkts && pl)
1707 pl->flags &= ~LINK_FAILINGOVER;
1713 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tol)
1715 unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
1717 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1720 l_ptr->tolerance = tol;
1721 l_ptr->keepalive_intv = msecs_to_jiffies(intv);
1722 l_ptr->abort_limit = tol / (jiffies_to_msecs(l_ptr->keepalive_intv));
1725 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1727 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE);
1730 l->backlog[TIPC_LOW_IMPORTANCE].limit = win / 2;
1731 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = win;
1732 l->backlog[TIPC_HIGH_IMPORTANCE].limit = win / 2 * 3;
1733 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = win * 2;
1734 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1737 /* tipc_link_find_owner - locate owner node of link by link's name
1738 * @net: the applicable net namespace
1739 * @name: pointer to link name string
1740 * @bearer_id: pointer to index in 'node->links' array where the link was found.
1742 * Returns pointer to node owning the link, or 0 if no matching link is found.
1744 static struct tipc_node *tipc_link_find_owner(struct net *net,
1745 const char *link_name,
1746 unsigned int *bearer_id)
1748 struct tipc_net *tn = net_generic(net, tipc_net_id);
1749 struct tipc_link *l_ptr;
1750 struct tipc_node *n_ptr;
1751 struct tipc_node *found_node = NULL;
1756 list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
1757 tipc_node_lock(n_ptr);
1758 for (i = 0; i < MAX_BEARERS; i++) {
1759 l_ptr = n_ptr->links[i].link;
1760 if (l_ptr && !strcmp(l_ptr->name, link_name)) {
1766 tipc_node_unlock(n_ptr);
1776 * link_reset_statistics - reset link statistics
1777 * @l_ptr: pointer to link
1779 static void link_reset_statistics(struct tipc_link *l_ptr)
1781 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
1782 l_ptr->stats.sent_info = l_ptr->snd_nxt;
1783 l_ptr->stats.recv_info = l_ptr->rcv_nxt;
1786 static void link_print(struct tipc_link *l_ptr, const char *str)
1788 struct tipc_net *tn = net_generic(l_ptr->owner->net, tipc_net_id);
1789 struct tipc_bearer *b_ptr;
1792 b_ptr = rcu_dereference_rtnl(tn->bearer_list[l_ptr->bearer_id]);
1794 pr_info("%s Link %x<%s>:", str, l_ptr->addr, b_ptr->name);
1797 if (link_working_unknown(l_ptr))
1799 else if (link_reset_reset(l_ptr))
1801 else if (link_reset_unknown(l_ptr))
1803 else if (link_working_working(l_ptr))
1809 /* Parse and validate nested (link) properties valid for media, bearer and link
1811 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1815 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1816 tipc_nl_prop_policy);
1820 if (props[TIPC_NLA_PROP_PRIO]) {
1823 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1824 if (prio > TIPC_MAX_LINK_PRI)
1828 if (props[TIPC_NLA_PROP_TOL]) {
1831 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1832 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1836 if (props[TIPC_NLA_PROP_WIN]) {
1839 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1840 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1847 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info)
1853 struct tipc_link *link;
1854 struct tipc_node *node;
1855 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
1856 struct net *net = sock_net(skb->sk);
1858 if (!info->attrs[TIPC_NLA_LINK])
1861 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
1862 info->attrs[TIPC_NLA_LINK],
1863 tipc_nl_link_policy);
1867 if (!attrs[TIPC_NLA_LINK_NAME])
1870 name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
1872 if (strcmp(name, tipc_bclink_name) == 0)
1873 return tipc_nl_bc_link_set(net, attrs);
1875 node = tipc_link_find_owner(net, name, &bearer_id);
1879 tipc_node_lock(node);
1881 link = node->links[bearer_id].link;
1887 if (attrs[TIPC_NLA_LINK_PROP]) {
1888 struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1890 err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
1897 if (props[TIPC_NLA_PROP_TOL]) {
1900 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1901 link_set_supervision_props(link, tol);
1902 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0);
1904 if (props[TIPC_NLA_PROP_PRIO]) {
1907 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1908 link->priority = prio;
1909 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio);
1911 if (props[TIPC_NLA_PROP_WIN]) {
1914 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1915 tipc_link_set_queue_limits(link, win);
1920 tipc_node_unlock(node);
1925 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1928 struct nlattr *stats;
1935 struct nla_map map[] = {
1936 {TIPC_NLA_STATS_RX_INFO, s->recv_info},
1937 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1938 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1939 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1940 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1941 {TIPC_NLA_STATS_TX_INFO, s->sent_info},
1942 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1943 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1944 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1945 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1946 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1947 s->msg_length_counts : 1},
1948 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1949 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1950 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1951 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1952 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1953 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1954 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1955 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1956 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1957 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1958 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1959 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1960 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1961 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1962 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1963 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1964 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1965 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1966 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1967 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1968 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1969 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1970 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1973 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1977 for (i = 0; i < ARRAY_SIZE(map); i++)
1978 if (nla_put_u32(skb, map[i].key, map[i].val))
1981 nla_nest_end(skb, stats);
1985 nla_nest_cancel(skb, stats);
1990 /* Caller should hold appropriate locks to protect the link */
1991 static int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1992 struct tipc_link *link, int nlflags)
1996 struct nlattr *attrs;
1997 struct nlattr *prop;
1998 struct tipc_net *tn = net_generic(net, tipc_net_id);
2000 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2001 nlflags, TIPC_NL_LINK_GET);
2005 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
2009 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2011 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
2012 tipc_cluster_mask(tn->own_addr)))
2014 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2016 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->rcv_nxt))
2018 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->snd_nxt))
2021 if (tipc_link_is_up(link))
2022 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2024 if (tipc_link_is_active(link))
2025 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2028 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
2031 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2033 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2035 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2038 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2040 nla_nest_end(msg->skb, prop);
2042 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2046 nla_nest_end(msg->skb, attrs);
2047 genlmsg_end(msg->skb, hdr);
2052 nla_nest_cancel(msg->skb, prop);
2054 nla_nest_cancel(msg->skb, attrs);
2056 genlmsg_cancel(msg->skb, hdr);
2061 /* Caller should hold node lock */
2062 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2063 struct tipc_node *node, u32 *prev_link)
2068 for (i = *prev_link; i < MAX_BEARERS; i++) {
2071 if (!node->links[i].link)
2074 err = __tipc_nl_add_link(net, msg,
2075 node->links[i].link, NLM_F_MULTI);
2084 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
2086 struct net *net = sock_net(skb->sk);
2087 struct tipc_net *tn = net_generic(net, tipc_net_id);
2088 struct tipc_node *node;
2089 struct tipc_nl_msg msg;
2090 u32 prev_node = cb->args[0];
2091 u32 prev_link = cb->args[1];
2092 int done = cb->args[2];
2099 msg.portid = NETLINK_CB(cb->skb).portid;
2100 msg.seq = cb->nlh->nlmsg_seq;
2104 node = tipc_node_find(net, prev_node);
2106 /* We never set seq or call nl_dump_check_consistent()
2107 * this means that setting prev_seq here will cause the
2108 * consistence check to fail in the netlink callback
2109 * handler. Resulting in the last NLMSG_DONE message
2110 * having the NLM_F_DUMP_INTR flag set.
2115 tipc_node_put(node);
2117 list_for_each_entry_continue_rcu(node, &tn->node_list,
2119 tipc_node_lock(node);
2120 err = __tipc_nl_add_node_links(net, &msg, node,
2122 tipc_node_unlock(node);
2126 prev_node = node->addr;
2129 err = tipc_nl_add_bc_link(net, &msg);
2133 list_for_each_entry_rcu(node, &tn->node_list, list) {
2134 tipc_node_lock(node);
2135 err = __tipc_nl_add_node_links(net, &msg, node,
2137 tipc_node_unlock(node);
2141 prev_node = node->addr;
2148 cb->args[0] = prev_node;
2149 cb->args[1] = prev_link;
2155 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info)
2157 struct net *net = genl_info_net(info);
2158 struct tipc_nl_msg msg;
2162 msg.portid = info->snd_portid;
2163 msg.seq = info->snd_seq;
2165 if (!info->attrs[TIPC_NLA_LINK_NAME])
2167 name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]);
2169 msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2173 if (strcmp(name, tipc_bclink_name) == 0) {
2174 err = tipc_nl_add_bc_link(net, &msg);
2176 nlmsg_free(msg.skb);
2181 struct tipc_node *node;
2182 struct tipc_link *link;
2184 node = tipc_link_find_owner(net, name, &bearer_id);
2188 tipc_node_lock(node);
2189 link = node->links[bearer_id].link;
2191 tipc_node_unlock(node);
2192 nlmsg_free(msg.skb);
2196 err = __tipc_nl_add_link(net, &msg, link, 0);
2197 tipc_node_unlock(node);
2199 nlmsg_free(msg.skb);
2204 return genlmsg_reply(msg.skb, info);
2207 int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
2211 unsigned int bearer_id;
2212 struct tipc_link *link;
2213 struct tipc_node *node;
2214 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2215 struct net *net = sock_net(skb->sk);
2217 if (!info->attrs[TIPC_NLA_LINK])
2220 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2221 info->attrs[TIPC_NLA_LINK],
2222 tipc_nl_link_policy);
2226 if (!attrs[TIPC_NLA_LINK_NAME])
2229 link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2231 if (strcmp(link_name, tipc_bclink_name) == 0) {
2232 err = tipc_bclink_reset_stats(net);
2238 node = tipc_link_find_owner(net, link_name, &bearer_id);
2242 tipc_node_lock(node);
2244 link = node->links[bearer_id].link;
2246 tipc_node_unlock(node);
2250 link_reset_statistics(link);
2252 tipc_node_unlock(node);