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:
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12 * notice, this list of conditions and the following disclaimer.
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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"
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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 * Only consumes message if there is an error
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);
356 tipc_link_reset(link);
359 /* Non-blocking sender: */
360 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending)
363 /* Create and schedule wakeup pseudo message */
364 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
365 addr, addr, oport, 0, 0);
368 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list);
369 TIPC_SKB_CB(skb)->chain_imp = imp;
370 skb_queue_tail(&link->wakeupq, skb);
371 link->stats.link_congs++;
374 __skb_queue_purge(list);
379 * link_prepare_wakeup - prepare users for wakeup after congestion
380 * @link: congested link
381 * Move a number of waiting users, as permitted by available space in
382 * the send queue, from link wait queue to node wait queue for wakeup
384 void link_prepare_wakeup(struct tipc_link *l)
386 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
388 struct sk_buff *skb, *tmp;
390 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
391 imp = TIPC_SKB_CB(skb)->chain_imp;
392 lim = l->window + l->backlog[imp].limit;
393 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
394 if ((pnd[imp] + l->backlog[imp].len) >= lim)
396 skb_unlink(skb, &l->wakeupq);
397 skb_queue_tail(l->inputq, skb);
398 l->owner->inputq = l->inputq;
399 l->owner->action_flags |= TIPC_MSG_EVT;
404 * tipc_link_reset_fragments - purge link's inbound message fragments queue
405 * @l_ptr: pointer to link
407 void tipc_link_reset_fragments(struct tipc_link *l_ptr)
409 kfree_skb(l_ptr->reasm_buf);
410 l_ptr->reasm_buf = NULL;
413 void tipc_link_purge_backlog(struct tipc_link *l)
415 __skb_queue_purge(&l->backlogq);
416 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
417 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
418 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
419 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
420 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
424 * tipc_link_purge_queues - purge all pkt queues associated with link
425 * @l_ptr: pointer to link
427 void tipc_link_purge_queues(struct tipc_link *l_ptr)
429 __skb_queue_purge(&l_ptr->deferdq);
430 __skb_queue_purge(&l_ptr->transmq);
431 tipc_link_purge_backlog(l_ptr);
432 tipc_link_reset_fragments(l_ptr);
435 void tipc_link_reset(struct tipc_link *l_ptr)
437 u32 prev_state = l_ptr->state;
438 int was_active_link = tipc_link_is_active(l_ptr);
439 struct tipc_node *owner = l_ptr->owner;
440 struct tipc_link *pl = tipc_parallel_link(l_ptr);
442 msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
444 /* Link is down, accept any session */
445 l_ptr->peer_session = INVALID_SESSION;
447 /* Prepare for renewed mtu size negotiation */
448 l_ptr->mtu = l_ptr->advertised_mtu;
450 l_ptr->state = RESET_UNKNOWN;
452 if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
455 tipc_node_link_down(l_ptr->owner, l_ptr->bearer_id);
456 tipc_bearer_remove_dest(owner->net, l_ptr->bearer_id, l_ptr->addr);
458 if (was_active_link && tipc_node_is_up(l_ptr->owner) && (pl != l_ptr)) {
459 l_ptr->flags |= LINK_FAILINGOVER;
460 l_ptr->failover_checkpt = l_ptr->rcv_nxt;
461 pl->failover_pkts = FIRST_FAILOVER;
462 pl->failover_checkpt = l_ptr->rcv_nxt;
463 pl->failover_skb = l_ptr->reasm_buf;
465 kfree_skb(l_ptr->reasm_buf);
467 /* Clean up all queues, except inputq: */
468 __skb_queue_purge(&l_ptr->transmq);
469 __skb_queue_purge(&l_ptr->deferdq);
471 owner->inputq = l_ptr->inputq;
472 skb_queue_splice_init(&l_ptr->wakeupq, owner->inputq);
473 if (!skb_queue_empty(owner->inputq))
474 owner->action_flags |= TIPC_MSG_EVT;
475 tipc_link_purge_backlog(l_ptr);
476 l_ptr->reasm_buf = NULL;
477 l_ptr->rcv_unacked = 0;
479 l_ptr->silent_intv_cnt = 0;
480 l_ptr->stale_count = 0;
481 link_reset_statistics(l_ptr);
484 static void link_activate(struct tipc_link *link)
486 struct tipc_node *node = link->owner;
489 link->stats.recv_info = 1;
490 link->silent_intv_cnt = 0;
491 tipc_node_link_up(node, link->bearer_id);
492 tipc_bearer_add_dest(node->net, link->bearer_id, link->addr);
496 * link_state_event - link finite state machine
497 * @l_ptr: pointer to link
498 * @event: state machine event to process
500 static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
502 struct tipc_link *other;
503 unsigned long timer_intv = l_ptr->keepalive_intv;
505 if (l_ptr->flags & LINK_STOPPED)
508 if (!(l_ptr->flags & LINK_STARTED) && (event != STARTING_EVT))
509 return; /* Not yet. */
511 if (l_ptr->flags & LINK_FAILINGOVER)
514 switch (l_ptr->state) {
515 case WORKING_WORKING:
517 case TRAFFIC_MSG_EVT:
519 l_ptr->silent_intv_cnt = 0;
522 if (!l_ptr->silent_intv_cnt) {
523 if (tipc_bclink_acks_missing(l_ptr->owner))
524 tipc_link_proto_xmit(l_ptr, STATE_MSG,
528 l_ptr->state = WORKING_UNKNOWN;
529 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0);
532 pr_debug("%s<%s>, requested by peer\n",
533 link_rst_msg, l_ptr->name);
534 tipc_link_reset(l_ptr);
535 l_ptr->state = RESET_RESET;
536 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
540 pr_debug("%s%u in WW state\n", link_unk_evt, event);
543 case WORKING_UNKNOWN:
545 case TRAFFIC_MSG_EVT:
547 l_ptr->state = WORKING_WORKING;
548 l_ptr->silent_intv_cnt = 0;
551 pr_debug("%s<%s>, requested by peer while probing\n",
552 link_rst_msg, l_ptr->name);
553 tipc_link_reset(l_ptr);
554 l_ptr->state = RESET_RESET;
555 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
559 if (!l_ptr->silent_intv_cnt) {
560 l_ptr->state = WORKING_WORKING;
561 if (tipc_bclink_acks_missing(l_ptr->owner))
562 tipc_link_proto_xmit(l_ptr, STATE_MSG,
564 } else if (l_ptr->silent_intv_cnt <
565 l_ptr->abort_limit) {
566 tipc_link_proto_xmit(l_ptr, STATE_MSG,
568 } else { /* Link has failed */
569 pr_debug("%s<%s>, peer not responding\n",
570 link_rst_msg, l_ptr->name);
571 tipc_link_reset(l_ptr);
572 l_ptr->state = RESET_UNKNOWN;
573 tipc_link_proto_xmit(l_ptr, RESET_MSG,
578 pr_err("%s%u in WU state\n", link_unk_evt, event);
583 case TRAFFIC_MSG_EVT:
586 other = node_active_link(l_ptr->owner, 0);
587 if (other && link_working_unknown(other))
589 l_ptr->state = WORKING_WORKING;
590 link_activate(l_ptr);
591 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0);
592 if (l_ptr->owner->working_links == 1)
593 tipc_link_sync_xmit(l_ptr);
596 l_ptr->state = RESET_RESET;
597 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
601 l_ptr->flags |= LINK_STARTED;
602 link_set_timer(l_ptr, timer_intv);
605 tipc_link_proto_xmit(l_ptr, RESET_MSG, 0, 0, 0, 0);
608 pr_err("%s%u in RU state\n", link_unk_evt, event);
613 case TRAFFIC_MSG_EVT:
615 other = node_active_link(l_ptr->owner, 0);
616 if (other && link_working_unknown(other))
618 l_ptr->state = WORKING_WORKING;
619 link_activate(l_ptr);
620 tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0);
621 if (l_ptr->owner->working_links == 1)
622 tipc_link_sync_xmit(l_ptr);
627 tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
631 pr_err("%s%u in RR state\n", link_unk_evt, event);
635 pr_err("Unknown link state %u/%u\n", l_ptr->state, event);
640 * __tipc_link_xmit(): same as tipc_link_xmit, but destlink is known & locked
642 * @list: chain of buffers containing message
644 * Consumes the buffer chain, except when returning -ELINKCONG,
645 * since the caller then may want to make more send attempts.
646 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
647 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
649 int __tipc_link_xmit(struct net *net, struct tipc_link *link,
650 struct sk_buff_head *list)
652 struct tipc_msg *msg = buf_msg(skb_peek(list));
653 unsigned int maxwin = link->window;
654 unsigned int i, imp = msg_importance(msg);
655 uint mtu = link->mtu;
656 u16 ack = mod(link->rcv_nxt - 1);
657 u16 seqno = link->snd_nxt;
658 u16 bc_last_in = link->owner->bclink.last_in;
659 struct tipc_media_addr *addr = &link->media_addr;
660 struct sk_buff_head *transmq = &link->transmq;
661 struct sk_buff_head *backlogq = &link->backlogq;
662 struct sk_buff *skb, *bskb;
664 /* Match msg importance against this and all higher backlog limits: */
665 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
666 if (unlikely(link->backlog[i].len >= link->backlog[i].limit))
667 return link_schedule_user(link, list);
669 if (unlikely(msg_size(msg) > mtu)) {
670 __skb_queue_purge(list);
673 /* Prepare each packet for sending, and add to relevant queue: */
674 while (skb_queue_len(list)) {
675 skb = skb_peek(list);
677 msg_set_seqno(msg, seqno);
678 msg_set_ack(msg, ack);
679 msg_set_bcast_ack(msg, bc_last_in);
681 if (likely(skb_queue_len(transmq) < maxwin)) {
683 __skb_queue_tail(transmq, skb);
684 tipc_bearer_send(net, link->bearer_id, skb, addr);
685 link->rcv_unacked = 0;
689 if (tipc_msg_bundle(skb_peek_tail(backlogq), msg, mtu)) {
690 kfree_skb(__skb_dequeue(list));
691 link->stats.sent_bundled++;
694 if (tipc_msg_make_bundle(&bskb, msg, mtu, link->addr)) {
695 kfree_skb(__skb_dequeue(list));
696 __skb_queue_tail(backlogq, bskb);
697 link->backlog[msg_importance(buf_msg(bskb))].len++;
698 link->stats.sent_bundled++;
699 link->stats.sent_bundles++;
702 link->backlog[imp].len += skb_queue_len(list);
703 skb_queue_splice_tail_init(list, backlogq);
705 link->snd_nxt = seqno;
709 static void skb2list(struct sk_buff *skb, struct sk_buff_head *list)
711 skb_queue_head_init(list);
712 __skb_queue_tail(list, skb);
715 static int __tipc_link_xmit_skb(struct tipc_link *link, struct sk_buff *skb)
717 struct sk_buff_head head;
719 skb2list(skb, &head);
720 return __tipc_link_xmit(link->owner->net, link, &head);
723 /* tipc_link_xmit_skb(): send single buffer to destination
724 * Buffers sent via this functon are generally TIPC_SYSTEM_IMPORTANCE
725 * messages, which will not be rejected
726 * The only exception is datagram messages rerouted after secondary
727 * lookup, which are rare and safe to dispose of anyway.
728 * TODO: Return real return value, and let callers use
729 * tipc_wait_for_sendpkt() where applicable
731 int tipc_link_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode,
734 struct sk_buff_head head;
737 skb2list(skb, &head);
738 rc = tipc_link_xmit(net, &head, dnode, selector);
739 if (rc == -ELINKCONG)
745 * tipc_link_xmit() is the general link level function for message sending
746 * @net: the applicable net namespace
747 * @list: chain of buffers containing message
748 * @dsz: amount of user data to be sent
749 * @dnode: address of destination node
750 * @selector: a number used for deterministic link selection
751 * Consumes the buffer chain, except when returning -ELINKCONG
752 * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE
754 int tipc_link_xmit(struct net *net, struct sk_buff_head *list, u32 dnode,
757 struct tipc_link *link = NULL;
758 struct tipc_node *node;
759 int rc = -EHOSTUNREACH;
761 node = tipc_node_find(net, dnode);
763 tipc_node_lock(node);
764 link = node_active_link(node, selector & 1);
766 rc = __tipc_link_xmit(net, link, list);
767 tipc_node_unlock(node);
773 if (likely(in_own_node(net, dnode))) {
774 tipc_sk_rcv(net, list);
778 __skb_queue_purge(list);
783 * tipc_link_sync_xmit - synchronize broadcast link endpoints.
785 * Give a newly added peer node the sequence number where it should
786 * start receiving and acking broadcast packets.
788 * Called with node locked
790 static void tipc_link_sync_xmit(struct tipc_link *link)
793 struct tipc_msg *msg;
795 skb = tipc_buf_acquire(INT_H_SIZE);
800 tipc_msg_init(link_own_addr(link), msg, BCAST_PROTOCOL, STATE_MSG,
801 INT_H_SIZE, link->addr);
802 msg_set_last_bcast(msg, link->owner->bclink.acked);
803 __tipc_link_xmit_skb(link, skb);
807 * tipc_link_sync_rcv - synchronize broadcast link endpoints.
808 * Receive the sequence number where we should start receiving and
809 * acking broadcast packets from a newly added peer node, and open
810 * up for reception of such packets.
812 * Called with node locked
814 static void tipc_link_sync_rcv(struct tipc_node *n, struct sk_buff *buf)
816 struct tipc_msg *msg = buf_msg(buf);
818 n->bclink.last_sent = n->bclink.last_in = msg_last_bcast(msg);
819 n->bclink.recv_permitted = true;
824 * tipc_link_push_packets - push unsent packets to bearer
826 * Push out the unsent messages of a link where congestion
827 * has abated. Node is locked.
829 * Called with node locked
831 void tipc_link_push_packets(struct tipc_link *link)
834 struct tipc_msg *msg;
835 u16 seqno = link->snd_nxt;
836 u16 ack = mod(link->rcv_nxt - 1);
838 while (skb_queue_len(&link->transmq) < link->window) {
839 skb = __skb_dequeue(&link->backlogq);
843 link->backlog[msg_importance(msg)].len--;
844 msg_set_ack(msg, ack);
845 msg_set_seqno(msg, seqno);
846 seqno = mod(seqno + 1);
847 msg_set_bcast_ack(msg, link->owner->bclink.last_in);
848 link->rcv_unacked = 0;
849 __skb_queue_tail(&link->transmq, skb);
850 tipc_bearer_send(link->owner->net, link->bearer_id,
851 skb, &link->media_addr);
853 link->snd_nxt = seqno;
856 void tipc_link_reset_all(struct tipc_node *node)
858 char addr_string[16];
861 tipc_node_lock(node);
863 pr_warn("Resetting all links to %s\n",
864 tipc_addr_string_fill(addr_string, node->addr));
866 for (i = 0; i < MAX_BEARERS; i++) {
867 if (node->links[i].link) {
868 link_print(node->links[i].link, "Resetting link\n");
869 tipc_link_reset(node->links[i].link);
873 tipc_node_unlock(node);
876 static void link_retransmit_failure(struct tipc_link *l_ptr,
879 struct tipc_msg *msg = buf_msg(buf);
880 struct net *net = l_ptr->owner->net;
882 pr_warn("Retransmission failure on link <%s>\n", l_ptr->name);
885 /* Handle failure on standard link */
886 link_print(l_ptr, "Resetting link\n");
887 tipc_link_reset(l_ptr);
890 /* Handle failure on broadcast link */
891 struct tipc_node *n_ptr;
892 char addr_string[16];
894 pr_info("Msg seq number: %u, ", msg_seqno(msg));
895 pr_cont("Outstanding acks: %lu\n",
896 (unsigned long) TIPC_SKB_CB(buf)->handle);
898 n_ptr = tipc_bclink_retransmit_to(net);
900 tipc_addr_string_fill(addr_string, n_ptr->addr);
901 pr_info("Broadcast link info for %s\n", addr_string);
902 pr_info("Reception permitted: %d, Acked: %u\n",
903 n_ptr->bclink.recv_permitted,
904 n_ptr->bclink.acked);
905 pr_info("Last in: %u, Oos state: %u, Last sent: %u\n",
906 n_ptr->bclink.last_in,
907 n_ptr->bclink.oos_state,
908 n_ptr->bclink.last_sent);
910 n_ptr->action_flags |= TIPC_BCAST_RESET;
911 l_ptr->stale_count = 0;
915 void tipc_link_retransmit(struct tipc_link *l_ptr, struct sk_buff *skb,
918 struct tipc_msg *msg;
925 /* Detect repeated retransmit failures */
926 if (l_ptr->last_retransm == msg_seqno(msg)) {
927 if (++l_ptr->stale_count > 100) {
928 link_retransmit_failure(l_ptr, skb);
932 l_ptr->last_retransm = msg_seqno(msg);
933 l_ptr->stale_count = 1;
936 skb_queue_walk_from(&l_ptr->transmq, skb) {
940 msg_set_ack(msg, mod(l_ptr->rcv_nxt - 1));
941 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
942 tipc_bearer_send(l_ptr->owner->net, l_ptr->bearer_id, skb,
945 l_ptr->stats.retransmitted++;
949 /* link_synch(): check if all packets arrived before the synch
950 * point have been consumed
951 * Returns true if the parallel links are synched, otherwise false
953 static bool link_synch(struct tipc_link *l)
955 unsigned int post_synch;
956 struct tipc_link *pl;
958 pl = tipc_parallel_link(l);
962 /* Was last pre-synch packet added to input queue ? */
963 if (less_eq(pl->rcv_nxt, l->synch_point))
966 /* Is it still in the input queue ? */
967 post_synch = mod(pl->rcv_nxt - l->synch_point) - 1;
968 if (skb_queue_len(pl->inputq) > post_synch)
971 l->flags &= ~LINK_SYNCHING;
975 static void link_retrieve_defq(struct tipc_link *link,
976 struct sk_buff_head *list)
980 if (skb_queue_empty(&link->deferdq))
983 seq_no = buf_seqno(skb_peek(&link->deferdq));
984 if (seq_no == link->rcv_nxt)
985 skb_queue_splice_tail_init(&link->deferdq, list);
989 * tipc_rcv - process TIPC packets/messages arriving from off-node
990 * @net: the applicable net namespace
992 * @b_ptr: pointer to bearer message arrived on
994 * Invoked with no locks held. Bearer pointer must point to a valid bearer
995 * structure (i.e. cannot be NULL), but bearer can be inactive.
997 void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b_ptr)
999 struct tipc_net *tn = net_generic(net, tipc_net_id);
1000 struct sk_buff_head head;
1001 struct tipc_node *n_ptr;
1002 struct tipc_link *l_ptr;
1003 struct sk_buff *skb1, *tmp;
1004 struct tipc_msg *msg;
1009 skb2list(skb, &head);
1011 while ((skb = __skb_dequeue(&head))) {
1012 /* Ensure message is well-formed */
1013 if (unlikely(!tipc_msg_validate(skb)))
1016 /* Handle arrival of a non-unicast link message */
1018 if (unlikely(msg_non_seq(msg))) {
1019 if (msg_user(msg) == LINK_CONFIG)
1020 tipc_disc_rcv(net, skb, b_ptr);
1022 tipc_bclink_rcv(net, skb);
1026 /* Discard unicast link messages destined for another node */
1027 if (unlikely(!msg_short(msg) &&
1028 (msg_destnode(msg) != tn->own_addr)))
1031 /* Locate neighboring node that sent message */
1032 n_ptr = tipc_node_find(net, msg_prevnode(msg));
1033 if (unlikely(!n_ptr))
1036 tipc_node_lock(n_ptr);
1037 /* Locate unicast link endpoint that should handle message */
1038 l_ptr = n_ptr->links[b_ptr->identity].link;
1039 if (unlikely(!l_ptr))
1042 /* Verify that communication with node is currently allowed */
1043 if ((n_ptr->action_flags & TIPC_WAIT_PEER_LINKS_DOWN) &&
1044 msg_user(msg) == LINK_PROTOCOL &&
1045 (msg_type(msg) == RESET_MSG ||
1046 msg_type(msg) == ACTIVATE_MSG) &&
1047 !msg_redundant_link(msg))
1048 n_ptr->action_flags &= ~TIPC_WAIT_PEER_LINKS_DOWN;
1050 if (tipc_node_blocked(n_ptr))
1053 /* Validate message sequence number info */
1054 seq_no = msg_seqno(msg);
1055 ackd = msg_ack(msg);
1057 /* Release acked messages */
1058 if (unlikely(n_ptr->bclink.acked != msg_bcast_ack(msg)))
1059 tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
1062 skb_queue_walk_safe(&l_ptr->transmq, skb1, tmp) {
1063 if (more(buf_seqno(skb1), ackd))
1065 __skb_unlink(skb1, &l_ptr->transmq);
1070 /* Try sending any messages link endpoint has pending */
1071 if (unlikely(skb_queue_len(&l_ptr->backlogq)))
1072 tipc_link_push_packets(l_ptr);
1074 if (released && !skb_queue_empty(&l_ptr->wakeupq))
1075 link_prepare_wakeup(l_ptr);
1077 /* Process the incoming packet */
1078 if (unlikely(!link_working_working(l_ptr))) {
1079 if (msg_user(msg) == LINK_PROTOCOL) {
1080 tipc_link_proto_rcv(l_ptr, skb);
1081 link_retrieve_defq(l_ptr, &head);
1086 /* Traffic message. Conditionally activate link */
1087 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1089 if (link_working_working(l_ptr)) {
1090 /* Re-insert buffer in front of queue */
1091 __skb_queue_head(&head, skb);
1098 /* Link is now in state WORKING_WORKING */
1099 if (unlikely(seq_no != l_ptr->rcv_nxt)) {
1100 link_handle_out_of_seq_msg(l_ptr, skb);
1101 link_retrieve_defq(l_ptr, &head);
1105 l_ptr->silent_intv_cnt = 0;
1107 /* Synchronize with parallel link if applicable */
1108 if (unlikely((l_ptr->flags & LINK_SYNCHING) && !msg_dup(msg))) {
1109 if (!link_synch(l_ptr))
1113 if (unlikely(!skb_queue_empty(&l_ptr->deferdq)))
1114 link_retrieve_defq(l_ptr, &head);
1115 if (unlikely(++l_ptr->rcv_unacked >= TIPC_MIN_LINK_WIN)) {
1116 l_ptr->stats.sent_acks++;
1117 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0);
1119 tipc_link_input(l_ptr, skb);
1122 tipc_node_unlock(n_ptr);
1123 tipc_node_put(n_ptr);
1130 /* tipc_data_input - deliver data and name distr msgs to upper layer
1132 * Consumes buffer if message is of right type
1133 * Node lock must be held
1135 static bool tipc_data_input(struct tipc_link *link, struct sk_buff *skb)
1137 struct tipc_node *node = link->owner;
1138 struct tipc_msg *msg = buf_msg(skb);
1139 u32 dport = msg_destport(msg);
1141 switch (msg_user(msg)) {
1142 case TIPC_LOW_IMPORTANCE:
1143 case TIPC_MEDIUM_IMPORTANCE:
1144 case TIPC_HIGH_IMPORTANCE:
1145 case TIPC_CRITICAL_IMPORTANCE:
1147 if (tipc_skb_queue_tail(link->inputq, skb, dport)) {
1148 node->inputq = link->inputq;
1149 node->action_flags |= TIPC_MSG_EVT;
1152 case NAME_DISTRIBUTOR:
1153 node->bclink.recv_permitted = true;
1154 node->namedq = link->namedq;
1155 skb_queue_tail(link->namedq, skb);
1156 if (skb_queue_len(link->namedq) == 1)
1157 node->action_flags |= TIPC_NAMED_MSG_EVT;
1160 case TUNNEL_PROTOCOL:
1161 case MSG_FRAGMENTER:
1162 case BCAST_PROTOCOL:
1165 pr_warn("Dropping received illegal msg type\n");
1171 /* tipc_link_input - process packet that has passed link protocol check
1174 * Node lock must be held
1176 static void tipc_link_input(struct tipc_link *link, struct sk_buff *skb)
1178 struct tipc_node *node = link->owner;
1179 struct tipc_msg *msg = buf_msg(skb);
1180 struct sk_buff *iskb;
1183 if (likely(tipc_data_input(link, skb)))
1186 switch (msg_user(msg)) {
1187 case TUNNEL_PROTOCOL:
1189 link->flags |= LINK_SYNCHING;
1190 link->synch_point = msg_seqno(msg_get_wrapped(msg));
1194 if (!tipc_link_failover_rcv(link, &skb))
1196 if (msg_user(buf_msg(skb)) != MSG_BUNDLER) {
1197 tipc_data_input(link, skb);
1201 link->stats.recv_bundles++;
1202 link->stats.recv_bundled += msg_msgcnt(msg);
1204 while (tipc_msg_extract(skb, &iskb, &pos))
1205 tipc_data_input(link, iskb);
1207 case MSG_FRAGMENTER:
1208 link->stats.recv_fragments++;
1209 if (tipc_buf_append(&link->reasm_buf, &skb)) {
1210 link->stats.recv_fragmented++;
1211 tipc_data_input(link, skb);
1212 } else if (!link->reasm_buf) {
1213 tipc_link_reset(link);
1216 case BCAST_PROTOCOL:
1217 tipc_link_sync_rcv(node, skb);
1225 * tipc_link_defer_pkt - Add out-of-sequence message to deferred reception queue
1227 * Returns increase in queue length (i.e. 0 or 1)
1229 u32 tipc_link_defer_pkt(struct sk_buff_head *list, struct sk_buff *skb)
1231 struct sk_buff *skb1;
1232 u16 seq_no = buf_seqno(skb);
1235 if (skb_queue_empty(list)) {
1236 __skb_queue_tail(list, skb);
1241 if (less(buf_seqno(skb_peek_tail(list)), seq_no)) {
1242 __skb_queue_tail(list, skb);
1246 /* Locate insertion point in queue, then insert; discard if duplicate */
1247 skb_queue_walk(list, skb1) {
1248 u16 curr_seqno = buf_seqno(skb1);
1250 if (seq_no == curr_seqno) {
1255 if (less(seq_no, curr_seqno))
1259 __skb_queue_before(list, skb1, skb);
1264 * link_handle_out_of_seq_msg - handle arrival of out-of-sequence packet
1266 static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
1267 struct sk_buff *buf)
1269 u32 seq_no = buf_seqno(buf);
1271 if (likely(msg_user(buf_msg(buf)) == LINK_PROTOCOL)) {
1272 tipc_link_proto_rcv(l_ptr, buf);
1276 /* Record OOS packet arrival */
1277 l_ptr->silent_intv_cnt = 0;
1280 * Discard packet if a duplicate; otherwise add it to deferred queue
1281 * and notify peer of gap as per protocol specification
1283 if (less(seq_no, l_ptr->rcv_nxt)) {
1284 l_ptr->stats.duplicates++;
1289 if (tipc_link_defer_pkt(&l_ptr->deferdq, buf)) {
1290 l_ptr->stats.deferred_recv++;
1291 if ((skb_queue_len(&l_ptr->deferdq) % TIPC_MIN_LINK_WIN) == 1)
1292 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0);
1294 l_ptr->stats.duplicates++;
1299 * Send protocol message to the other endpoint.
1301 void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg,
1302 u32 gap, u32 tolerance, u32 priority)
1304 struct sk_buff *buf = NULL;
1305 struct tipc_msg *msg = l_ptr->pmsg;
1306 u32 msg_size = sizeof(l_ptr->proto_msg);
1310 /* Don't send protocol message during link failover */
1311 if (l_ptr->flags & LINK_FAILINGOVER)
1314 /* Abort non-RESET send if communication with node is prohibited */
1315 if ((tipc_node_blocked(l_ptr->owner)) && (msg_typ != RESET_MSG))
1318 /* Create protocol message with "out-of-sequence" sequence number */
1319 msg_set_type(msg, msg_typ);
1320 msg_set_net_plane(msg, l_ptr->net_plane);
1321 msg_set_bcast_ack(msg, l_ptr->owner->bclink.last_in);
1322 msg_set_last_bcast(msg, tipc_bclink_get_last_sent(l_ptr->owner->net));
1324 if (msg_typ == STATE_MSG) {
1325 u16 next_sent = l_ptr->snd_nxt;
1327 if (!tipc_link_is_up(l_ptr))
1329 msg_set_next_sent(msg, next_sent);
1330 if (!skb_queue_empty(&l_ptr->deferdq)) {
1331 last_rcv = buf_seqno(skb_peek(&l_ptr->deferdq));
1332 gap = mod(last_rcv - l_ptr->rcv_nxt);
1334 msg_set_seq_gap(msg, gap);
1336 l_ptr->stats.sent_nacks++;
1337 msg_set_link_tolerance(msg, tolerance);
1338 msg_set_linkprio(msg, priority);
1339 msg_set_max_pkt(msg, l_ptr->mtu);
1340 msg_set_ack(msg, mod(l_ptr->rcv_nxt - 1));
1341 msg_set_probe(msg, probe_msg != 0);
1343 l_ptr->stats.sent_probes++;
1344 l_ptr->stats.sent_states++;
1345 } else { /* RESET_MSG or ACTIVATE_MSG */
1346 msg_set_ack(msg, mod(l_ptr->failover_checkpt - 1));
1347 msg_set_seq_gap(msg, 0);
1348 msg_set_next_sent(msg, 1);
1349 msg_set_probe(msg, 0);
1350 msg_set_link_tolerance(msg, l_ptr->tolerance);
1351 msg_set_linkprio(msg, l_ptr->priority);
1352 msg_set_max_pkt(msg, l_ptr->advertised_mtu);
1355 r_flag = (l_ptr->owner->working_links > tipc_link_is_up(l_ptr));
1356 msg_set_redundant_link(msg, r_flag);
1357 msg_set_linkprio(msg, l_ptr->priority);
1358 msg_set_size(msg, msg_size);
1360 msg_set_seqno(msg, mod(l_ptr->snd_nxt + (0xffff / 2)));
1362 buf = tipc_buf_acquire(msg_size);
1366 skb_copy_to_linear_data(buf, msg, sizeof(l_ptr->proto_msg));
1367 buf->priority = TC_PRIO_CONTROL;
1368 tipc_bearer_send(l_ptr->owner->net, l_ptr->bearer_id, buf,
1369 &l_ptr->media_addr);
1370 l_ptr->rcv_unacked = 0;
1375 * Receive protocol message :
1376 * Note that network plane id propagates through the network, and may
1377 * change at any time. The node with lowest address rules
1379 static void tipc_link_proto_rcv(struct tipc_link *l_ptr,
1380 struct sk_buff *buf)
1384 struct tipc_msg *msg = buf_msg(buf);
1386 if (l_ptr->flags & LINK_FAILINGOVER)
1389 if (l_ptr->net_plane != msg_net_plane(msg))
1390 if (link_own_addr(l_ptr) > msg_prevnode(msg))
1391 l_ptr->net_plane = msg_net_plane(msg);
1393 switch (msg_type(msg)) {
1396 if (!link_working_unknown(l_ptr) &&
1397 (l_ptr->peer_session != INVALID_SESSION)) {
1398 if (less_eq(msg_session(msg), l_ptr->peer_session))
1399 break; /* duplicate or old reset: ignore */
1402 if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
1403 link_working_unknown(l_ptr))) {
1405 * peer has lost contact -- don't allow peer's links
1406 * to reactivate before we recognize loss & clean up
1408 l_ptr->owner->action_flags |= TIPC_WAIT_OWN_LINKS_DOWN;
1411 link_state_event(l_ptr, RESET_MSG);
1415 /* Update link settings according other endpoint's values */
1416 strcpy((strrchr(l_ptr->name, ':') + 1), (char *)msg_data(msg));
1418 msg_tol = msg_link_tolerance(msg);
1419 if (msg_tol > l_ptr->tolerance)
1420 link_set_supervision_props(l_ptr, msg_tol);
1422 if (msg_linkprio(msg) > l_ptr->priority)
1423 l_ptr->priority = msg_linkprio(msg);
1425 if (l_ptr->mtu > msg_max_pkt(msg))
1426 l_ptr->mtu = msg_max_pkt(msg);
1428 /* Synchronize broadcast link info, if not done previously */
1429 if (!tipc_node_is_up(l_ptr->owner)) {
1430 l_ptr->owner->bclink.last_sent =
1431 l_ptr->owner->bclink.last_in =
1432 msg_last_bcast(msg);
1433 l_ptr->owner->bclink.oos_state = 0;
1436 l_ptr->peer_session = msg_session(msg);
1437 l_ptr->peer_bearer_id = msg_bearer_id(msg);
1439 if (msg_type(msg) == ACTIVATE_MSG)
1440 link_state_event(l_ptr, ACTIVATE_MSG);
1444 msg_tol = msg_link_tolerance(msg);
1446 link_set_supervision_props(l_ptr, msg_tol);
1448 if (msg_linkprio(msg) &&
1449 (msg_linkprio(msg) != l_ptr->priority)) {
1450 pr_debug("%s<%s>, priority change %u->%u\n",
1451 link_rst_msg, l_ptr->name,
1452 l_ptr->priority, msg_linkprio(msg));
1453 l_ptr->priority = msg_linkprio(msg);
1454 tipc_link_reset(l_ptr); /* Enforce change to take effect */
1458 /* Record reception; force mismatch at next timeout: */
1459 l_ptr->silent_intv_cnt = 0;
1461 link_state_event(l_ptr, TRAFFIC_MSG_EVT);
1462 l_ptr->stats.recv_states++;
1463 if (link_reset_unknown(l_ptr))
1466 if (less_eq(l_ptr->rcv_nxt, msg_next_sent(msg)))
1467 rec_gap = mod(msg_next_sent(msg) - l_ptr->rcv_nxt);
1470 l_ptr->stats.recv_probes++;
1472 /* Protocol message before retransmits, reduce loss risk */
1473 if (l_ptr->owner->bclink.recv_permitted)
1474 tipc_bclink_update_link_state(l_ptr->owner,
1475 msg_last_bcast(msg));
1477 if (rec_gap || (msg_probe(msg))) {
1478 tipc_link_proto_xmit(l_ptr, STATE_MSG, 0,
1481 if (msg_seq_gap(msg)) {
1482 l_ptr->stats.recv_nacks++;
1483 tipc_link_retransmit(l_ptr, skb_peek(&l_ptr->transmq),
1493 /* tipc_link_tunnel_xmit(): Tunnel one packet via a link belonging to
1494 * a different bearer. Owner node is locked.
1496 static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr,
1497 struct tipc_msg *tunnel_hdr,
1498 struct tipc_msg *msg,
1501 struct tipc_link *tunnel;
1502 struct sk_buff *skb;
1503 u32 length = msg_size(msg);
1505 tunnel = node_active_link(l_ptr->owner, selector & 1);
1506 if (!tipc_link_is_up(tunnel)) {
1507 pr_warn("%stunnel link no longer available\n", link_co_err);
1510 msg_set_size(tunnel_hdr, length + INT_H_SIZE);
1511 skb = tipc_buf_acquire(length + INT_H_SIZE);
1513 pr_warn("%sunable to send tunnel msg\n", link_co_err);
1516 skb_copy_to_linear_data(skb, tunnel_hdr, INT_H_SIZE);
1517 skb_copy_to_linear_data_offset(skb, INT_H_SIZE, msg, length);
1518 __tipc_link_xmit_skb(tunnel, skb);
1522 /* tipc_link_failover_send_queue(): A link has gone down, but a second
1523 * link is still active. We can do failover. Tunnel the failing link's
1524 * whole send queue via the remaining link. This way, we don't lose
1525 * any packets, and sequence order is preserved for subsequent traffic
1526 * sent over the remaining link. Owner node is locked.
1528 void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
1531 struct tipc_link *tunnel = node_active_link(l_ptr->owner, 0);
1532 struct tipc_msg tunnel_hdr;
1533 struct sk_buff *skb;
1539 tipc_msg_init(link_own_addr(l_ptr), &tunnel_hdr, TUNNEL_PROTOCOL,
1540 FAILOVER_MSG, INT_H_SIZE, l_ptr->addr);
1542 skb_queue_walk(&l_ptr->backlogq, skb) {
1543 msg_set_seqno(buf_msg(skb), l_ptr->snd_nxt);
1544 l_ptr->snd_nxt = mod(l_ptr->snd_nxt + 1);
1546 skb_queue_splice_tail_init(&l_ptr->backlogq, &l_ptr->transmq);
1547 tipc_link_purge_backlog(l_ptr);
1548 msgcount = skb_queue_len(&l_ptr->transmq);
1549 msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
1550 msg_set_msgcnt(&tunnel_hdr, msgcount);
1552 if (skb_queue_empty(&l_ptr->transmq)) {
1553 skb = tipc_buf_acquire(INT_H_SIZE);
1555 skb_copy_to_linear_data(skb, &tunnel_hdr, INT_H_SIZE);
1556 msg_set_size(&tunnel_hdr, INT_H_SIZE);
1557 __tipc_link_xmit_skb(tunnel, skb);
1559 pr_warn("%sunable to send changeover msg\n",
1565 split_bundles = (node_active_link(l_ptr->owner, 0) !=
1566 node_active_link(l_ptr->owner, 0));
1568 skb_queue_walk(&l_ptr->transmq, skb) {
1569 struct tipc_msg *msg = buf_msg(skb);
1571 if ((msg_user(msg) == MSG_BUNDLER) && split_bundles) {
1572 struct tipc_msg *m = msg_get_wrapped(msg);
1573 unchar *pos = (unchar *)m;
1575 msgcount = msg_msgcnt(msg);
1576 while (msgcount--) {
1577 msg_set_seqno(m, msg_seqno(msg));
1578 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, m,
1579 msg_link_selector(m));
1580 pos += align(msg_size(m));
1581 m = (struct tipc_msg *)pos;
1584 tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, msg,
1585 msg_link_selector(msg));
1590 /* tipc_link_dup_queue_xmit(): A second link has become active. Tunnel a
1591 * duplicate of the first link's send queue via the new link. This way, we
1592 * are guaranteed that currently queued packets from a socket are delivered
1593 * before future traffic from the same socket, even if this is using the
1594 * new link. The last arriving copy of each duplicate packet is dropped at
1595 * the receiving end by the regular protocol check, so packet cardinality
1596 * and sequence order is preserved per sender/receiver socket pair.
1597 * Owner node is locked.
1599 void tipc_link_dup_queue_xmit(struct tipc_link *link,
1600 struct tipc_link *tnl)
1602 struct sk_buff *skb;
1603 struct tipc_msg tnl_hdr;
1604 struct sk_buff_head *queue = &link->transmq;
1608 tipc_msg_init(link_own_addr(link), &tnl_hdr, TUNNEL_PROTOCOL,
1609 SYNCH_MSG, INT_H_SIZE, link->addr);
1610 mcnt = skb_queue_len(&link->transmq) + skb_queue_len(&link->backlogq);
1611 msg_set_msgcnt(&tnl_hdr, mcnt);
1612 msg_set_bearer_id(&tnl_hdr, link->peer_bearer_id);
1615 skb_queue_walk(queue, skb) {
1616 struct sk_buff *outskb;
1617 struct tipc_msg *msg = buf_msg(skb);
1618 u32 len = msg_size(msg);
1620 msg_set_ack(msg, mod(link->rcv_nxt - 1));
1621 msg_set_bcast_ack(msg, link->owner->bclink.last_in);
1622 msg_set_size(&tnl_hdr, len + INT_H_SIZE);
1623 outskb = tipc_buf_acquire(len + INT_H_SIZE);
1624 if (outskb == NULL) {
1625 pr_warn("%sunable to send duplicate msg\n",
1629 skb_copy_to_linear_data(outskb, &tnl_hdr, INT_H_SIZE);
1630 skb_copy_to_linear_data_offset(outskb, INT_H_SIZE,
1632 __tipc_link_xmit_skb(tnl, outskb);
1633 if (!tipc_link_is_up(link))
1636 if (queue == &link->backlogq)
1638 seqno = link->snd_nxt;
1639 skb_queue_walk(&link->backlogq, skb) {
1640 msg_set_seqno(buf_msg(skb), seqno);
1641 seqno = mod(seqno + 1);
1643 queue = &link->backlogq;
1647 /* tipc_link_failover_rcv(): Receive a tunnelled FAILOVER_MSG packet
1648 * Owner node is locked.
1650 static bool tipc_link_failover_rcv(struct tipc_link *link,
1651 struct sk_buff **skb)
1653 struct tipc_msg *msg = buf_msg(*skb);
1654 struct sk_buff *iskb = NULL;
1655 struct tipc_link *pl = NULL;
1656 int bearer_id = msg_bearer_id(msg);
1659 if (msg_type(msg) != FAILOVER_MSG) {
1660 pr_warn("%sunknown tunnel pkt received\n", link_co_err);
1663 if (bearer_id >= MAX_BEARERS)
1666 if (bearer_id == link->bearer_id)
1669 pl = link->owner->links[bearer_id].link;
1670 if (pl && tipc_link_is_up(pl))
1671 tipc_link_reset(pl);
1673 if (link->failover_pkts == FIRST_FAILOVER)
1674 link->failover_pkts = msg_msgcnt(msg);
1676 /* Should we expect an inner packet? */
1677 if (!link->failover_pkts)
1680 if (!tipc_msg_extract(*skb, &iskb, &pos)) {
1681 pr_warn("%sno inner failover pkt\n", link_co_err);
1685 link->failover_pkts--;
1688 /* Was this packet already delivered? */
1689 if (less(buf_seqno(iskb), link->failover_checkpt)) {
1694 if (msg_user(buf_msg(iskb)) == MSG_FRAGMENTER) {
1695 link->stats.recv_fragments++;
1696 tipc_buf_append(&link->failover_skb, &iskb);
1699 if (!link->failover_pkts && pl)
1700 pl->flags &= ~LINK_FAILINGOVER;
1706 static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tol)
1708 unsigned long intv = ((tol / 4) > 500) ? 500 : tol / 4;
1710 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1713 l_ptr->tolerance = tol;
1714 l_ptr->keepalive_intv = msecs_to_jiffies(intv);
1715 l_ptr->abort_limit = tol / (jiffies_to_msecs(l_ptr->keepalive_intv));
1718 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1720 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE);
1723 l->backlog[TIPC_LOW_IMPORTANCE].limit = win / 2;
1724 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = win;
1725 l->backlog[TIPC_HIGH_IMPORTANCE].limit = win / 2 * 3;
1726 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = win * 2;
1727 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1730 /* tipc_link_find_owner - locate owner node of link by link's name
1731 * @net: the applicable net namespace
1732 * @name: pointer to link name string
1733 * @bearer_id: pointer to index in 'node->links' array where the link was found.
1735 * Returns pointer to node owning the link, or 0 if no matching link is found.
1737 static struct tipc_node *tipc_link_find_owner(struct net *net,
1738 const char *link_name,
1739 unsigned int *bearer_id)
1741 struct tipc_net *tn = net_generic(net, tipc_net_id);
1742 struct tipc_link *l_ptr;
1743 struct tipc_node *n_ptr;
1744 struct tipc_node *found_node = NULL;
1749 list_for_each_entry_rcu(n_ptr, &tn->node_list, list) {
1750 tipc_node_lock(n_ptr);
1751 for (i = 0; i < MAX_BEARERS; i++) {
1752 l_ptr = n_ptr->links[i].link;
1753 if (l_ptr && !strcmp(l_ptr->name, link_name)) {
1759 tipc_node_unlock(n_ptr);
1769 * link_reset_statistics - reset link statistics
1770 * @l_ptr: pointer to link
1772 static void link_reset_statistics(struct tipc_link *l_ptr)
1774 memset(&l_ptr->stats, 0, sizeof(l_ptr->stats));
1775 l_ptr->stats.sent_info = l_ptr->snd_nxt;
1776 l_ptr->stats.recv_info = l_ptr->rcv_nxt;
1779 static void link_print(struct tipc_link *l_ptr, const char *str)
1781 struct tipc_net *tn = net_generic(l_ptr->owner->net, tipc_net_id);
1782 struct tipc_bearer *b_ptr;
1785 b_ptr = rcu_dereference_rtnl(tn->bearer_list[l_ptr->bearer_id]);
1787 pr_info("%s Link %x<%s>:", str, l_ptr->addr, b_ptr->name);
1790 if (link_working_unknown(l_ptr))
1792 else if (link_reset_reset(l_ptr))
1794 else if (link_reset_unknown(l_ptr))
1796 else if (link_working_working(l_ptr))
1802 /* Parse and validate nested (link) properties valid for media, bearer and link
1804 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1808 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1809 tipc_nl_prop_policy);
1813 if (props[TIPC_NLA_PROP_PRIO]) {
1816 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1817 if (prio > TIPC_MAX_LINK_PRI)
1821 if (props[TIPC_NLA_PROP_TOL]) {
1824 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1825 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1829 if (props[TIPC_NLA_PROP_WIN]) {
1832 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1833 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1840 int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info)
1846 struct tipc_link *link;
1847 struct tipc_node *node;
1848 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
1849 struct net *net = sock_net(skb->sk);
1851 if (!info->attrs[TIPC_NLA_LINK])
1854 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
1855 info->attrs[TIPC_NLA_LINK],
1856 tipc_nl_link_policy);
1860 if (!attrs[TIPC_NLA_LINK_NAME])
1863 name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
1865 if (strcmp(name, tipc_bclink_name) == 0)
1866 return tipc_nl_bc_link_set(net, attrs);
1868 node = tipc_link_find_owner(net, name, &bearer_id);
1872 tipc_node_lock(node);
1874 link = node->links[bearer_id].link;
1880 if (attrs[TIPC_NLA_LINK_PROP]) {
1881 struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
1883 err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP],
1890 if (props[TIPC_NLA_PROP_TOL]) {
1893 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1894 link_set_supervision_props(link, tol);
1895 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, tol, 0);
1897 if (props[TIPC_NLA_PROP_PRIO]) {
1900 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1901 link->priority = prio;
1902 tipc_link_proto_xmit(link, STATE_MSG, 0, 0, 0, prio);
1904 if (props[TIPC_NLA_PROP_WIN]) {
1907 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1908 tipc_link_set_queue_limits(link, win);
1913 tipc_node_unlock(node);
1918 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1921 struct nlattr *stats;
1928 struct nla_map map[] = {
1929 {TIPC_NLA_STATS_RX_INFO, s->recv_info},
1930 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1931 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1932 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1933 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1934 {TIPC_NLA_STATS_TX_INFO, s->sent_info},
1935 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1936 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1937 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1938 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1939 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1940 s->msg_length_counts : 1},
1941 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1942 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1943 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1944 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1945 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1946 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1947 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1948 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1949 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1950 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1951 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1952 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1953 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1954 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1955 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1956 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1957 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1958 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1959 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1960 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1961 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1962 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1963 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1966 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1970 for (i = 0; i < ARRAY_SIZE(map); i++)
1971 if (nla_put_u32(skb, map[i].key, map[i].val))
1974 nla_nest_end(skb, stats);
1978 nla_nest_cancel(skb, stats);
1983 /* Caller should hold appropriate locks to protect the link */
1984 static int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1985 struct tipc_link *link, int nlflags)
1989 struct nlattr *attrs;
1990 struct nlattr *prop;
1991 struct tipc_net *tn = net_generic(net, tipc_net_id);
1993 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1994 nlflags, TIPC_NL_LINK_GET);
1998 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
2002 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2004 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
2005 tipc_cluster_mask(tn->own_addr)))
2007 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2009 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->rcv_nxt))
2011 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->snd_nxt))
2014 if (tipc_link_is_up(link))
2015 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2017 if (tipc_link_is_active(link))
2018 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2021 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
2024 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2026 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2028 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2031 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2033 nla_nest_end(msg->skb, prop);
2035 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2039 nla_nest_end(msg->skb, attrs);
2040 genlmsg_end(msg->skb, hdr);
2045 nla_nest_cancel(msg->skb, prop);
2047 nla_nest_cancel(msg->skb, attrs);
2049 genlmsg_cancel(msg->skb, hdr);
2054 /* Caller should hold node lock */
2055 static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg,
2056 struct tipc_node *node, u32 *prev_link)
2061 for (i = *prev_link; i < MAX_BEARERS; i++) {
2064 if (!node->links[i].link)
2067 err = __tipc_nl_add_link(net, msg,
2068 node->links[i].link, NLM_F_MULTI);
2077 int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb)
2079 struct net *net = sock_net(skb->sk);
2080 struct tipc_net *tn = net_generic(net, tipc_net_id);
2081 struct tipc_node *node;
2082 struct tipc_nl_msg msg;
2083 u32 prev_node = cb->args[0];
2084 u32 prev_link = cb->args[1];
2085 int done = cb->args[2];
2092 msg.portid = NETLINK_CB(cb->skb).portid;
2093 msg.seq = cb->nlh->nlmsg_seq;
2097 node = tipc_node_find(net, prev_node);
2099 /* We never set seq or call nl_dump_check_consistent()
2100 * this means that setting prev_seq here will cause the
2101 * consistence check to fail in the netlink callback
2102 * handler. Resulting in the last NLMSG_DONE message
2103 * having the NLM_F_DUMP_INTR flag set.
2108 tipc_node_put(node);
2110 list_for_each_entry_continue_rcu(node, &tn->node_list,
2112 tipc_node_lock(node);
2113 err = __tipc_nl_add_node_links(net, &msg, node,
2115 tipc_node_unlock(node);
2119 prev_node = node->addr;
2122 err = tipc_nl_add_bc_link(net, &msg);
2126 list_for_each_entry_rcu(node, &tn->node_list, list) {
2127 tipc_node_lock(node);
2128 err = __tipc_nl_add_node_links(net, &msg, node,
2130 tipc_node_unlock(node);
2134 prev_node = node->addr;
2141 cb->args[0] = prev_node;
2142 cb->args[1] = prev_link;
2148 int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info)
2150 struct net *net = genl_info_net(info);
2151 struct tipc_nl_msg msg;
2155 msg.portid = info->snd_portid;
2156 msg.seq = info->snd_seq;
2158 if (!info->attrs[TIPC_NLA_LINK_NAME])
2160 name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]);
2162 msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
2166 if (strcmp(name, tipc_bclink_name) == 0) {
2167 err = tipc_nl_add_bc_link(net, &msg);
2169 nlmsg_free(msg.skb);
2174 struct tipc_node *node;
2175 struct tipc_link *link;
2177 node = tipc_link_find_owner(net, name, &bearer_id);
2181 tipc_node_lock(node);
2182 link = node->links[bearer_id].link;
2184 tipc_node_unlock(node);
2185 nlmsg_free(msg.skb);
2189 err = __tipc_nl_add_link(net, &msg, link, 0);
2190 tipc_node_unlock(node);
2192 nlmsg_free(msg.skb);
2197 return genlmsg_reply(msg.skb, info);
2200 int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info)
2204 unsigned int bearer_id;
2205 struct tipc_link *link;
2206 struct tipc_node *node;
2207 struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1];
2208 struct net *net = sock_net(skb->sk);
2210 if (!info->attrs[TIPC_NLA_LINK])
2213 err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX,
2214 info->attrs[TIPC_NLA_LINK],
2215 tipc_nl_link_policy);
2219 if (!attrs[TIPC_NLA_LINK_NAME])
2222 link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]);
2224 if (strcmp(link_name, tipc_bclink_name) == 0) {
2225 err = tipc_bclink_reset_stats(net);
2231 node = tipc_link_find_owner(net, link_name, &bearer_id);
2235 tipc_node_lock(node);
2237 link = node->links[bearer_id].link;
2239 tipc_node_unlock(node);
2243 link_reset_statistics(link);
2245 tipc_node_unlock(node);