2 * net/tipc/link.c: TIPC link code
4 * Copyright (c) 1996-2007, 2012-2016, 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 u32 sent_info; /* used in counting # sent packets */
50 u32 recv_info; /* used in counting # recv'd packets */
67 u32 link_congs; /* # port sends blocked by congestion */
70 u32 max_queue_sz; /* send queue size high water mark */
71 u32 accu_queue_sz; /* used for send queue size profiling */
72 u32 queue_sz_counts; /* used for send queue size profiling */
73 u32 msg_length_counts; /* used for message length profiling */
74 u32 msg_lengths_total; /* used for message length profiling */
75 u32 msg_length_profile[7]; /* used for msg. length profiling */
79 * struct tipc_link - TIPC link data structure
80 * @addr: network address of link's peer node
81 * @name: link name character string
82 * @media_addr: media address to use when sending messages over link
84 * @net: pointer to namespace struct
85 * @refcnt: reference counter for permanent references (owner node & timer)
86 * @peer_session: link session # being used by peer end of link
87 * @peer_bearer_id: bearer id used by link's peer endpoint
88 * @bearer_id: local bearer id used by link
89 * @tolerance: minimum link continuity loss needed to reset link [in ms]
90 * @abort_limit: # of unacknowledged continuity probes needed to reset link
91 * @state: current state of link FSM
92 * @peer_caps: bitmap describing capabilities of peer node
93 * @silent_intv_cnt: # of timer intervals without any reception from peer
94 * @proto_msg: template for control messages generated by link
95 * @pmsg: convenience pointer to "proto_msg" field
96 * @priority: current link priority
97 * @net_plane: current link network plane ('A' through 'H')
98 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
99 * @exp_msg_count: # of tunnelled messages expected during link changeover
100 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
101 * @mtu: current maximum packet size for this link
102 * @advertised_mtu: advertised own mtu when link is being established
103 * @transmitq: queue for sent, non-acked messages
104 * @backlogq: queue for messages waiting to be sent
105 * @snt_nxt: next sequence number to use for outbound messages
106 * @last_retransmitted: sequence number of most recently retransmitted message
107 * @stale_count: # of identical retransmit requests made by peer
108 * @ackers: # of peers that needs to ack each packet before it can be released
109 * @acked: # last packet acked by a certain peer. Used for broadcast.
110 * @rcv_nxt: next sequence number to expect for inbound messages
111 * @deferred_queue: deferred queue saved OOS b'cast message received from node
112 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
113 * @inputq: buffer queue for messages to be delivered upwards
114 * @namedq: buffer queue for name table messages to be delivered upwards
115 * @next_out: ptr to first unsent outbound message in queue
116 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
117 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
118 * @reasm_buf: head of partially reassembled inbound message fragments
119 * @bc_rcvr: marks that this is a broadcast receiver link
120 * @stats: collects statistics regarding link activity
124 char name[TIPC_MAX_LINK_NAME];
127 /* Management and link supervision data */
138 char if_name[TIPC_MAX_IF_NAME];
145 struct sk_buff *failover_reasm_skb;
147 /* Max packet negotiation */
152 struct sk_buff_head transmq;
153 struct sk_buff_head backlogq;
166 struct sk_buff_head deferdq;
167 struct sk_buff_head *inputq;
168 struct sk_buff_head *namedq;
170 /* Congestion handling */
171 struct sk_buff_head wakeupq;
173 /* Fragmentation/reassembly */
174 struct sk_buff *reasm_buf;
179 struct tipc_link *bc_rcvlink;
180 struct tipc_link *bc_sndlink;
185 struct tipc_stats stats;
189 * Error message prefixes
191 static const char *link_co_err = "Link tunneling error, ";
192 static const char *link_rst_msg = "Resetting link ";
194 /* Send states for broadcast NACKs
197 BC_NACK_SND_CONDITIONAL,
198 BC_NACK_SND_UNCONDITIONAL,
199 BC_NACK_SND_SUPPRESS,
203 * Interval between NACKs when packets arrive out of order
205 #define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
207 /* Wildcard value for link session numbers. When it is known that
208 * peer endpoint is down, any session number must be accepted.
210 #define ANY_SESSION 0x10000
215 LINK_ESTABLISHED = 0xe,
216 LINK_ESTABLISHING = 0xe << 4,
217 LINK_RESET = 0x1 << 8,
218 LINK_RESETTING = 0x2 << 12,
219 LINK_PEER_RESET = 0xd << 16,
220 LINK_FAILINGOVER = 0xf << 20,
221 LINK_SYNCHING = 0xc << 24
224 /* Link FSM state checking routines
226 static int link_is_up(struct tipc_link *l)
228 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
231 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
232 struct sk_buff_head *xmitq);
233 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
234 u16 rcvgap, int tolerance, int priority,
235 struct sk_buff_head *xmitq);
236 static void link_print(struct tipc_link *l, const char *str);
237 static void tipc_link_build_nack_msg(struct tipc_link *l,
238 struct sk_buff_head *xmitq);
239 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
240 struct sk_buff_head *xmitq);
241 static bool tipc_link_release_pkts(struct tipc_link *l, u16 to);
244 * Simple non-static link routines (i.e. referenced outside this file)
246 bool tipc_link_is_up(struct tipc_link *l)
248 return link_is_up(l);
251 bool tipc_link_peer_is_down(struct tipc_link *l)
253 return l->state == LINK_PEER_RESET;
256 bool tipc_link_is_reset(struct tipc_link *l)
258 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
261 bool tipc_link_is_establishing(struct tipc_link *l)
263 return l->state == LINK_ESTABLISHING;
266 bool tipc_link_is_synching(struct tipc_link *l)
268 return l->state == LINK_SYNCHING;
271 bool tipc_link_is_failingover(struct tipc_link *l)
273 return l->state == LINK_FAILINGOVER;
276 bool tipc_link_is_blocked(struct tipc_link *l)
278 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
281 static bool link_is_bc_sndlink(struct tipc_link *l)
283 return !l->bc_sndlink;
286 static bool link_is_bc_rcvlink(struct tipc_link *l)
288 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
291 int tipc_link_is_active(struct tipc_link *l)
296 void tipc_link_set_active(struct tipc_link *l, bool active)
301 u32 tipc_link_id(struct tipc_link *l)
303 return l->peer_bearer_id << 16 | l->bearer_id;
306 int tipc_link_window(struct tipc_link *l)
311 int tipc_link_prio(struct tipc_link *l)
316 unsigned long tipc_link_tolerance(struct tipc_link *l)
321 struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
326 char tipc_link_plane(struct tipc_link *l)
331 void tipc_link_add_bc_peer(struct tipc_link *snd_l,
332 struct tipc_link *uc_l,
333 struct sk_buff_head *xmitq)
335 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
338 rcv_l->acked = snd_l->snd_nxt - 1;
339 snd_l->state = LINK_ESTABLISHED;
340 tipc_link_build_bc_init_msg(uc_l, xmitq);
343 void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
344 struct tipc_link *rcv_l,
345 struct sk_buff_head *xmitq)
347 u16 ack = snd_l->snd_nxt - 1;
350 tipc_link_bc_ack_rcv(rcv_l, ack, xmitq);
351 tipc_link_reset(rcv_l);
352 rcv_l->state = LINK_RESET;
353 if (!snd_l->ackers) {
354 tipc_link_reset(snd_l);
355 snd_l->state = LINK_RESET;
356 __skb_queue_purge(xmitq);
360 int tipc_link_bc_peers(struct tipc_link *l)
365 void tipc_link_set_mtu(struct tipc_link *l, int mtu)
370 int tipc_link_mtu(struct tipc_link *l)
375 u16 tipc_link_rcv_nxt(struct tipc_link *l)
380 u16 tipc_link_acked(struct tipc_link *l)
385 char *tipc_link_name(struct tipc_link *l)
391 * tipc_link_create - create a new link
392 * @n: pointer to associated node
393 * @if_name: associated interface name
394 * @bearer_id: id (index) of associated bearer
395 * @tolerance: link tolerance to be used by link
396 * @net_plane: network plane (A,B,c..) this link belongs to
397 * @mtu: mtu to be advertised by link
398 * @priority: priority to be used by link
399 * @window: send window to be used by link
400 * @session: session to be used by link
401 * @ownnode: identity of own node
402 * @peer: node id of peer node
403 * @peer_caps: bitmap describing peer node capabilities
404 * @bc_sndlink: the namespace global link used for broadcast sending
405 * @bc_rcvlink: the peer specific link used for broadcast reception
406 * @inputq: queue to put messages ready for delivery
407 * @namedq: queue to put binding table update messages ready for delivery
408 * @link: return value, pointer to put the created link
410 * Returns true if link was created, otherwise false
412 bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
413 int tolerance, char net_plane, u32 mtu, int priority,
414 int window, u32 session, u32 ownnode, u32 peer,
416 struct tipc_link *bc_sndlink,
417 struct tipc_link *bc_rcvlink,
418 struct sk_buff_head *inputq,
419 struct sk_buff_head *namedq,
420 struct tipc_link **link)
424 l = kzalloc(sizeof(*l), GFP_ATOMIC);
428 l->session = session;
430 /* Note: peer i/f name is completed by reset/activate message */
431 sprintf(l->name, "%u.%u.%u:%s-%u.%u.%u:unknown",
432 tipc_zone(ownnode), tipc_cluster(ownnode), tipc_node(ownnode),
433 if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer));
434 strcpy(l->if_name, if_name);
436 l->peer_caps = peer_caps;
438 l->peer_session = ANY_SESSION;
439 l->bearer_id = bearer_id;
440 l->tolerance = tolerance;
441 l->net_plane = net_plane;
442 l->advertised_mtu = mtu;
444 l->priority = priority;
445 tipc_link_set_queue_limits(l, window);
447 l->bc_sndlink = bc_sndlink;
448 l->bc_rcvlink = bc_rcvlink;
451 l->state = LINK_RESETTING;
452 __skb_queue_head_init(&l->transmq);
453 __skb_queue_head_init(&l->backlogq);
454 __skb_queue_head_init(&l->deferdq);
455 skb_queue_head_init(&l->wakeupq);
456 skb_queue_head_init(l->inputq);
461 * tipc_link_bc_create - create new link to be used for broadcast
462 * @n: pointer to associated node
463 * @mtu: mtu to be used
464 * @window: send window to be used
465 * @inputq: queue to put messages ready for delivery
466 * @namedq: queue to put binding table update messages ready for delivery
467 * @link: return value, pointer to put the created link
469 * Returns true if link was created, otherwise false
471 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
472 int mtu, int window, u16 peer_caps,
473 struct sk_buff_head *inputq,
474 struct sk_buff_head *namedq,
475 struct tipc_link *bc_sndlink,
476 struct tipc_link **link)
480 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
481 0, ownnode, peer, peer_caps, bc_sndlink,
482 NULL, inputq, namedq, link))
486 strcpy(l->name, tipc_bclink_name);
488 l->state = LINK_RESET;
492 /* Broadcast send link is always up */
493 if (link_is_bc_sndlink(l))
494 l->state = LINK_ESTABLISHED;
500 * tipc_link_fsm_evt - link finite state machine
501 * @l: pointer to link
502 * @evt: state machine event to be processed
504 int tipc_link_fsm_evt(struct tipc_link *l, int evt)
511 case LINK_PEER_RESET_EVT:
512 l->state = LINK_PEER_RESET;
515 l->state = LINK_RESET;
517 case LINK_FAILURE_EVT:
518 case LINK_FAILOVER_BEGIN_EVT:
519 case LINK_ESTABLISH_EVT:
520 case LINK_FAILOVER_END_EVT:
521 case LINK_SYNCH_BEGIN_EVT:
522 case LINK_SYNCH_END_EVT:
529 case LINK_PEER_RESET_EVT:
530 l->state = LINK_ESTABLISHING;
532 case LINK_FAILOVER_BEGIN_EVT:
533 l->state = LINK_FAILINGOVER;
534 case LINK_FAILURE_EVT:
536 case LINK_ESTABLISH_EVT:
537 case LINK_FAILOVER_END_EVT:
539 case LINK_SYNCH_BEGIN_EVT:
540 case LINK_SYNCH_END_EVT:
545 case LINK_PEER_RESET:
548 l->state = LINK_ESTABLISHING;
550 case LINK_PEER_RESET_EVT:
551 case LINK_ESTABLISH_EVT:
552 case LINK_FAILURE_EVT:
554 case LINK_SYNCH_BEGIN_EVT:
555 case LINK_SYNCH_END_EVT:
556 case LINK_FAILOVER_BEGIN_EVT:
557 case LINK_FAILOVER_END_EVT:
562 case LINK_FAILINGOVER:
564 case LINK_FAILOVER_END_EVT:
565 l->state = LINK_RESET;
567 case LINK_PEER_RESET_EVT:
569 case LINK_ESTABLISH_EVT:
570 case LINK_FAILURE_EVT:
572 case LINK_FAILOVER_BEGIN_EVT:
573 case LINK_SYNCH_BEGIN_EVT:
574 case LINK_SYNCH_END_EVT:
579 case LINK_ESTABLISHING:
581 case LINK_ESTABLISH_EVT:
582 l->state = LINK_ESTABLISHED;
584 case LINK_FAILOVER_BEGIN_EVT:
585 l->state = LINK_FAILINGOVER;
588 l->state = LINK_RESET;
590 case LINK_FAILURE_EVT:
591 case LINK_PEER_RESET_EVT:
592 case LINK_SYNCH_BEGIN_EVT:
593 case LINK_FAILOVER_END_EVT:
595 case LINK_SYNCH_END_EVT:
600 case LINK_ESTABLISHED:
602 case LINK_PEER_RESET_EVT:
603 l->state = LINK_PEER_RESET;
604 rc |= TIPC_LINK_DOWN_EVT;
606 case LINK_FAILURE_EVT:
607 l->state = LINK_RESETTING;
608 rc |= TIPC_LINK_DOWN_EVT;
611 l->state = LINK_RESET;
613 case LINK_ESTABLISH_EVT:
614 case LINK_SYNCH_END_EVT:
616 case LINK_SYNCH_BEGIN_EVT:
617 l->state = LINK_SYNCHING;
619 case LINK_FAILOVER_BEGIN_EVT:
620 case LINK_FAILOVER_END_EVT:
627 case LINK_PEER_RESET_EVT:
628 l->state = LINK_PEER_RESET;
629 rc |= TIPC_LINK_DOWN_EVT;
631 case LINK_FAILURE_EVT:
632 l->state = LINK_RESETTING;
633 rc |= TIPC_LINK_DOWN_EVT;
636 l->state = LINK_RESET;
638 case LINK_ESTABLISH_EVT:
639 case LINK_SYNCH_BEGIN_EVT:
641 case LINK_SYNCH_END_EVT:
642 l->state = LINK_ESTABLISHED;
644 case LINK_FAILOVER_BEGIN_EVT:
645 case LINK_FAILOVER_END_EVT:
651 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
655 pr_err("Illegal FSM event %x in state %x on link %s\n",
656 evt, l->state, l->name);
660 /* link_profile_stats - update statistical profiling of traffic
662 static void link_profile_stats(struct tipc_link *l)
665 struct tipc_msg *msg;
668 /* Update counters used in statistical profiling of send traffic */
669 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
670 l->stats.queue_sz_counts++;
672 skb = skb_peek(&l->transmq);
676 length = msg_size(msg);
678 if (msg_user(msg) == MSG_FRAGMENTER) {
679 if (msg_type(msg) != FIRST_FRAGMENT)
681 length = msg_size(msg_get_wrapped(msg));
683 l->stats.msg_lengths_total += length;
684 l->stats.msg_length_counts++;
686 l->stats.msg_length_profile[0]++;
687 else if (length <= 256)
688 l->stats.msg_length_profile[1]++;
689 else if (length <= 1024)
690 l->stats.msg_length_profile[2]++;
691 else if (length <= 4096)
692 l->stats.msg_length_profile[3]++;
693 else if (length <= 16384)
694 l->stats.msg_length_profile[4]++;
695 else if (length <= 32768)
696 l->stats.msg_length_profile[5]++;
698 l->stats.msg_length_profile[6]++;
701 /* tipc_link_timeout - perform periodic task as instructed from node timeout
703 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
709 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
710 u16 bc_acked = l->bc_rcvlink->acked;
712 link_profile_stats(l);
715 case LINK_ESTABLISHED:
717 if (l->silent_intv_cnt > l->abort_limit)
718 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
720 state = bc_acked != bc_snt;
721 probe = l->silent_intv_cnt;
722 l->silent_intv_cnt++;
725 setup = l->rst_cnt++ <= 4;
726 setup |= !(l->rst_cnt % 16);
729 case LINK_ESTABLISHING:
733 case LINK_PEER_RESET:
735 case LINK_FAILINGOVER:
741 if (state || probe || setup)
742 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, xmitq);
748 * link_schedule_user - schedule a message sender for wakeup after congestion
749 * @link: congested link
750 * @list: message that was attempted sent
751 * Create pseudo msg to send back to user when congestion abates
752 * Does not consume buffer list
754 static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list)
756 struct tipc_msg *msg = buf_msg(skb_peek(list));
757 int imp = msg_importance(msg);
758 u32 oport = msg_origport(msg);
759 u32 addr = tipc_own_addr(link->net);
762 /* This really cannot happen... */
763 if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) {
764 pr_warn("%s<%s>, send queue full", link_rst_msg, link->name);
767 /* Non-blocking sender: */
768 if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending)
771 /* Create and schedule wakeup pseudo message */
772 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
773 addr, addr, oport, 0, 0);
776 TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list);
777 TIPC_SKB_CB(skb)->chain_imp = imp;
778 skb_queue_tail(&link->wakeupq, skb);
779 link->stats.link_congs++;
784 * link_prepare_wakeup - prepare users for wakeup after congestion
785 * @link: congested link
786 * Move a number of waiting users, as permitted by available space in
787 * the send queue, from link wait queue to node wait queue for wakeup
789 void link_prepare_wakeup(struct tipc_link *l)
791 int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,};
793 struct sk_buff *skb, *tmp;
795 skb_queue_walk_safe(&l->wakeupq, skb, tmp) {
796 imp = TIPC_SKB_CB(skb)->chain_imp;
797 lim = l->window + l->backlog[imp].limit;
798 pnd[imp] += TIPC_SKB_CB(skb)->chain_sz;
799 if ((pnd[imp] + l->backlog[imp].len) >= lim)
801 skb_unlink(skb, &l->wakeupq);
802 skb_queue_tail(l->inputq, skb);
806 void tipc_link_reset(struct tipc_link *l)
808 l->peer_session = ANY_SESSION;
810 l->mtu = l->advertised_mtu;
811 __skb_queue_purge(&l->transmq);
812 __skb_queue_purge(&l->deferdq);
813 skb_queue_splice_init(&l->wakeupq, l->inputq);
814 __skb_queue_purge(&l->backlogq);
815 l->backlog[TIPC_LOW_IMPORTANCE].len = 0;
816 l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0;
817 l->backlog[TIPC_HIGH_IMPORTANCE].len = 0;
818 l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0;
819 l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0;
820 kfree_skb(l->reasm_buf);
821 kfree_skb(l->failover_reasm_skb);
823 l->failover_reasm_skb = NULL;
828 l->silent_intv_cnt = 0;
830 l->stats.recv_info = 0;
832 l->bc_peer_is_up = false;
833 tipc_link_reset_stats(l);
837 * tipc_link_xmit(): enqueue buffer list according to queue situation
839 * @list: chain of buffers containing message
840 * @xmitq: returned list of packets to be sent by caller
842 * Consumes the buffer chain, except when returning -ELINKCONG,
843 * since the caller then may want to make more send attempts.
844 * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
845 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
847 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
848 struct sk_buff_head *xmitq)
850 struct tipc_msg *hdr = buf_msg(skb_peek(list));
851 unsigned int maxwin = l->window;
852 unsigned int i, imp = msg_importance(hdr);
853 unsigned int mtu = l->mtu;
854 u16 ack = l->rcv_nxt - 1;
855 u16 seqno = l->snd_nxt;
856 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
857 struct sk_buff_head *transmq = &l->transmq;
858 struct sk_buff_head *backlogq = &l->backlogq;
859 struct sk_buff *skb, *_skb, *bskb;
861 /* Match msg importance against this and all higher backlog limits: */
862 for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) {
863 if (unlikely(l->backlog[i].len >= l->backlog[i].limit))
864 return link_schedule_user(l, list);
866 if (unlikely(msg_size(hdr) > mtu)) {
867 skb_queue_purge(list);
871 /* Prepare each packet for sending, and add to relevant queue: */
872 while (skb_queue_len(list)) {
873 skb = skb_peek(list);
875 msg_set_seqno(hdr, seqno);
876 msg_set_ack(hdr, ack);
877 msg_set_bcast_ack(hdr, bc_ack);
879 if (likely(skb_queue_len(transmq) < maxwin)) {
880 _skb = skb_clone(skb, GFP_ATOMIC);
882 skb_queue_purge(list);
886 __skb_queue_tail(transmq, skb);
887 __skb_queue_tail(xmitq, _skb);
888 TIPC_SKB_CB(skb)->ackers = l->ackers;
893 if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) {
894 kfree_skb(__skb_dequeue(list));
895 l->stats.sent_bundled++;
898 if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) {
899 kfree_skb(__skb_dequeue(list));
900 __skb_queue_tail(backlogq, bskb);
901 l->backlog[msg_importance(buf_msg(bskb))].len++;
902 l->stats.sent_bundled++;
903 l->stats.sent_bundles++;
906 l->backlog[imp].len += skb_queue_len(list);
907 skb_queue_splice_tail_init(list, backlogq);
913 void tipc_link_advance_backlog(struct tipc_link *l, struct sk_buff_head *xmitq)
915 struct sk_buff *skb, *_skb;
916 struct tipc_msg *hdr;
917 u16 seqno = l->snd_nxt;
918 u16 ack = l->rcv_nxt - 1;
919 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
921 while (skb_queue_len(&l->transmq) < l->window) {
922 skb = skb_peek(&l->backlogq);
925 _skb = skb_clone(skb, GFP_ATOMIC);
928 __skb_dequeue(&l->backlogq);
930 l->backlog[msg_importance(hdr)].len--;
931 __skb_queue_tail(&l->transmq, skb);
932 __skb_queue_tail(xmitq, _skb);
933 TIPC_SKB_CB(skb)->ackers = l->ackers;
934 msg_set_seqno(hdr, seqno);
935 msg_set_ack(hdr, ack);
936 msg_set_bcast_ack(hdr, bc_ack);
943 static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb)
945 struct tipc_msg *hdr = buf_msg(skb);
947 pr_warn("Retransmission failure on link <%s>\n", l->name);
948 link_print(l, "Resetting link ");
949 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
950 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
951 pr_info("sqno %u, prev: %x, src: %x\n",
952 msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr));
955 int tipc_link_retrans(struct tipc_link *l, u16 from, u16 to,
956 struct sk_buff_head *xmitq)
958 struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
959 struct tipc_msg *hdr;
960 u16 ack = l->rcv_nxt - 1;
961 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
966 /* Detect repeated retransmit failures on same packet */
967 if (likely(l->last_retransm != buf_seqno(skb))) {
968 l->last_retransm = buf_seqno(skb);
970 } else if (++l->stale_count > 100) {
971 link_retransmit_failure(l, skb);
972 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
975 /* Move forward to where retransmission should start */
976 skb_queue_walk(&l->transmq, skb) {
977 if (!less(buf_seqno(skb), from))
981 skb_queue_walk_from(&l->transmq, skb) {
982 if (more(buf_seqno(skb), to))
985 _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
989 msg_set_ack(hdr, ack);
990 msg_set_bcast_ack(hdr, bc_ack);
991 _skb->priority = TC_PRIO_CONTROL;
992 __skb_queue_tail(xmitq, _skb);
993 l->stats.retransmitted++;
998 /* tipc_data_input - deliver data and name distr msgs to upper layer
1000 * Consumes buffer if message is of right type
1001 * Node lock must be held
1003 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1004 struct sk_buff_head *inputq)
1006 switch (msg_user(buf_msg(skb))) {
1007 case TIPC_LOW_IMPORTANCE:
1008 case TIPC_MEDIUM_IMPORTANCE:
1009 case TIPC_HIGH_IMPORTANCE:
1010 case TIPC_CRITICAL_IMPORTANCE:
1012 skb_queue_tail(inputq, skb);
1014 case NAME_DISTRIBUTOR:
1015 l->bc_rcvlink->state = LINK_ESTABLISHED;
1016 skb_queue_tail(l->namedq, skb);
1019 case TUNNEL_PROTOCOL:
1020 case MSG_FRAGMENTER:
1021 case BCAST_PROTOCOL:
1024 pr_warn("Dropping received illegal msg type\n");
1030 /* tipc_link_input - process packet that has passed link protocol check
1034 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1035 struct sk_buff_head *inputq)
1037 struct tipc_msg *hdr = buf_msg(skb);
1038 struct sk_buff **reasm_skb = &l->reasm_buf;
1039 struct sk_buff *iskb;
1040 struct sk_buff_head tmpq;
1041 int usr = msg_user(hdr);
1046 if (unlikely(usr == TUNNEL_PROTOCOL)) {
1047 if (msg_type(hdr) == SYNCH_MSG) {
1048 __skb_queue_purge(&l->deferdq);
1051 if (!tipc_msg_extract(skb, &iskb, &ipos))
1056 if (less(msg_seqno(hdr), l->drop_point))
1058 if (tipc_data_input(l, skb, inputq))
1060 usr = msg_user(hdr);
1061 reasm_skb = &l->failover_reasm_skb;
1064 if (usr == MSG_BUNDLER) {
1065 skb_queue_head_init(&tmpq);
1066 l->stats.recv_bundles++;
1067 l->stats.recv_bundled += msg_msgcnt(hdr);
1068 while (tipc_msg_extract(skb, &iskb, &pos))
1069 tipc_data_input(l, iskb, &tmpq);
1070 tipc_skb_queue_splice_tail(&tmpq, inputq);
1072 } else if (usr == MSG_FRAGMENTER) {
1073 l->stats.recv_fragments++;
1074 if (tipc_buf_append(reasm_skb, &skb)) {
1075 l->stats.recv_fragmented++;
1076 tipc_data_input(l, skb, inputq);
1077 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1078 pr_warn_ratelimited("Unable to build fragment list\n");
1079 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1082 } else if (usr == BCAST_PROTOCOL) {
1083 tipc_bcast_lock(l->net);
1084 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1085 tipc_bcast_unlock(l->net);
1092 static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
1094 bool released = false;
1095 struct sk_buff *skb, *tmp;
1097 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1098 if (more(buf_seqno(skb), acked))
1100 __skb_unlink(skb, &l->transmq);
1107 /* tipc_link_build_state_msg: prepare link state message for transmission
1109 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1110 * risk of ack storms towards the sender
1112 int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1117 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1118 if (link_is_bc_rcvlink(l)) {
1119 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1122 return TIPC_LINK_SND_BC_ACK;
1127 l->stats.sent_acks++;
1128 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1132 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1134 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1136 int mtyp = RESET_MSG;
1137 struct sk_buff *skb;
1139 if (l->state == LINK_ESTABLISHING)
1140 mtyp = ACTIVATE_MSG;
1142 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq);
1144 /* Inform peer that this endpoint is going down if applicable */
1145 skb = skb_peek_tail(xmitq);
1146 if (skb && (l->state == LINK_RESET))
1147 msg_set_peer_stopping(buf_msg(skb), 1);
1150 /* tipc_link_build_nack_msg: prepare link nack message for transmission
1152 static void tipc_link_build_nack_msg(struct tipc_link *l,
1153 struct sk_buff_head *xmitq)
1155 u32 def_cnt = ++l->stats.deferred_recv;
1157 if (link_is_bc_rcvlink(l))
1160 if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
1161 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq);
1164 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1165 * @l: the link that should handle the message
1167 * @xmitq: queue to place packets to be sent after this call
1169 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1170 struct sk_buff_head *xmitq)
1172 struct sk_buff_head *defq = &l->deferdq;
1173 struct tipc_msg *hdr;
1174 u16 seqno, rcv_nxt, win_lim;
1179 seqno = msg_seqno(hdr);
1180 rcv_nxt = l->rcv_nxt;
1181 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1183 /* Verify and update link state */
1184 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1185 return tipc_link_proto_rcv(l, skb, xmitq);
1187 if (unlikely(!link_is_up(l))) {
1188 if (l->state == LINK_ESTABLISHING)
1189 rc = TIPC_LINK_UP_EVT;
1193 /* Don't send probe at next timeout expiration */
1194 l->silent_intv_cnt = 0;
1196 /* Drop if outside receive window */
1197 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1198 l->stats.duplicates++;
1202 /* Forward queues and wake up waiting users */
1203 if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) {
1204 tipc_link_advance_backlog(l, xmitq);
1205 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1206 link_prepare_wakeup(l);
1209 /* Defer delivery if sequence gap */
1210 if (unlikely(seqno != rcv_nxt)) {
1211 __tipc_skb_queue_sorted(defq, seqno, skb);
1212 tipc_link_build_nack_msg(l, xmitq);
1216 /* Deliver packet */
1218 l->stats.recv_info++;
1219 if (!tipc_data_input(l, skb, l->inputq))
1220 rc |= tipc_link_input(l, skb, l->inputq);
1221 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1222 rc |= tipc_link_build_state_msg(l, xmitq);
1223 if (unlikely(rc & ~TIPC_LINK_SND_BC_ACK))
1225 } while ((skb = __skb_dequeue(defq)));
1233 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1234 u16 rcvgap, int tolerance, int priority,
1235 struct sk_buff_head *xmitq)
1237 struct sk_buff *skb;
1238 struct tipc_msg *hdr;
1239 struct sk_buff_head *dfq = &l->deferdq;
1240 bool node_up = link_is_up(l->bc_rcvlink);
1242 /* Don't send protocol message during reset or link failover */
1243 if (tipc_link_is_blocked(l))
1246 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1249 if (!skb_queue_empty(dfq))
1250 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1252 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1253 TIPC_MAX_IF_NAME, l->addr,
1254 tipc_own_addr(l->net), 0, 0, 0);
1259 msg_set_session(hdr, l->session);
1260 msg_set_bearer_id(hdr, l->bearer_id);
1261 msg_set_net_plane(hdr, l->net_plane);
1262 msg_set_next_sent(hdr, l->snd_nxt);
1263 msg_set_ack(hdr, l->rcv_nxt - 1);
1264 msg_set_bcast_ack(hdr, l->bc_rcvlink->rcv_nxt - 1);
1265 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1266 msg_set_link_tolerance(hdr, tolerance);
1267 msg_set_linkprio(hdr, priority);
1268 msg_set_redundant_link(hdr, node_up);
1269 msg_set_seq_gap(hdr, 0);
1270 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1272 if (mtyp == STATE_MSG) {
1273 msg_set_seq_gap(hdr, rcvgap);
1274 msg_set_size(hdr, INT_H_SIZE);
1275 msg_set_probe(hdr, probe);
1276 l->stats.sent_states++;
1279 /* RESET_MSG or ACTIVATE_MSG */
1280 msg_set_max_pkt(hdr, l->advertised_mtu);
1281 strcpy(msg_data(hdr), l->if_name);
1284 l->stats.sent_probes++;
1286 l->stats.sent_nacks++;
1287 skb->priority = TC_PRIO_CONTROL;
1288 __skb_queue_tail(xmitq, skb);
1291 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1292 * with contents of the link's transmit and backlog queues.
1294 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1295 int mtyp, struct sk_buff_head *xmitq)
1297 struct sk_buff *skb, *tnlskb;
1298 struct tipc_msg *hdr, tnlhdr;
1299 struct sk_buff_head *queue = &l->transmq;
1300 struct sk_buff_head tmpxq, tnlq;
1301 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1306 skb_queue_head_init(&tnlq);
1307 skb_queue_head_init(&tmpxq);
1309 /* At least one packet required for safe algorithm => add dummy */
1310 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1311 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
1312 0, 0, TIPC_ERR_NO_PORT);
1314 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1317 skb_queue_tail(&tnlq, skb);
1318 tipc_link_xmit(l, &tnlq, &tmpxq);
1319 __skb_queue_purge(&tmpxq);
1321 /* Initialize reusable tunnel packet header */
1322 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
1323 mtyp, INT_H_SIZE, l->addr);
1324 pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
1325 msg_set_msgcnt(&tnlhdr, pktcnt);
1326 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
1328 /* Wrap each packet into a tunnel packet */
1329 skb_queue_walk(queue, skb) {
1331 if (queue == &l->backlogq)
1332 msg_set_seqno(hdr, seqno++);
1333 pktlen = msg_size(hdr);
1334 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
1335 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE);
1337 pr_warn("%sunable to send packet\n", link_co_err);
1340 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
1341 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
1342 __skb_queue_tail(&tnlq, tnlskb);
1344 if (queue != &l->backlogq) {
1345 queue = &l->backlogq;
1349 tipc_link_xmit(tnl, &tnlq, xmitq);
1351 if (mtyp == FAILOVER_MSG) {
1352 tnl->drop_point = l->rcv_nxt;
1353 tnl->failover_reasm_skb = l->reasm_buf;
1354 l->reasm_buf = NULL;
1358 /* tipc_link_proto_rcv(): receive link level protocol message :
1359 * Note that network plane id propagates through the network, and may
1360 * change at any time. The node with lowest numerical id determines
1363 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
1364 struct sk_buff_head *xmitq)
1366 struct tipc_msg *hdr = buf_msg(skb);
1368 u16 ack = msg_ack(hdr);
1369 u16 gap = msg_seq_gap(hdr);
1370 u16 peers_snd_nxt = msg_next_sent(hdr);
1371 u16 peers_tol = msg_link_tolerance(hdr);
1372 u16 peers_prio = msg_linkprio(hdr);
1373 u16 rcv_nxt = l->rcv_nxt;
1374 int mtyp = msg_type(hdr);
1378 if (tipc_link_is_blocked(l) || !xmitq)
1381 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
1382 l->net_plane = msg_net_plane(hdr);
1387 /* Ignore duplicate RESET with old session number */
1388 if ((less_eq(msg_session(hdr), l->peer_session)) &&
1389 (l->peer_session != ANY_SESSION))
1397 /* Complete own link name with peer's interface name */
1398 if_name = strrchr(l->name, ':') + 1;
1399 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
1401 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
1403 strncpy(if_name, msg_data(hdr), TIPC_MAX_IF_NAME);
1405 /* Update own tolerance if peer indicates a non-zero value */
1406 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1407 l->tolerance = peers_tol;
1409 /* Update own priority if peer's priority is higher */
1410 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
1411 l->priority = peers_prio;
1413 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
1414 if (msg_peer_stopping(hdr))
1415 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1416 else if ((mtyp == RESET_MSG) || !link_is_up(l))
1417 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
1419 /* ACTIVATE_MSG takes up link if it was already locally reset */
1420 if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING))
1421 rc = TIPC_LINK_UP_EVT;
1423 l->peer_session = msg_session(hdr);
1424 l->peer_bearer_id = msg_bearer_id(hdr);
1425 if (l->mtu > msg_max_pkt(hdr))
1426 l->mtu = msg_max_pkt(hdr);
1431 /* Update own tolerance if peer indicates a non-zero value */
1432 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL))
1433 l->tolerance = peers_tol;
1435 if (peers_prio && in_range(peers_prio, TIPC_MIN_LINK_PRI,
1436 TIPC_MAX_LINK_PRI)) {
1437 l->priority = peers_prio;
1438 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1441 l->silent_intv_cnt = 0;
1442 l->stats.recv_states++;
1444 l->stats.recv_probes++;
1446 if (!link_is_up(l)) {
1447 if (l->state == LINK_ESTABLISHING)
1448 rc = TIPC_LINK_UP_EVT;
1452 /* Send NACK if peer has sent pkts we haven't received yet */
1453 if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
1454 rcvgap = peers_snd_nxt - l->rcv_nxt;
1455 if (rcvgap || (msg_probe(hdr)))
1456 tipc_link_build_proto_msg(l, STATE_MSG, 0, rcvgap,
1458 tipc_link_release_pkts(l, ack);
1460 /* If NACK, retransmit will now start at right position */
1462 rc = tipc_link_retrans(l, ack + 1, ack + gap, xmitq);
1463 l->stats.recv_nacks++;
1466 tipc_link_advance_backlog(l, xmitq);
1467 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1468 link_prepare_wakeup(l);
1475 /* tipc_link_build_bc_proto_msg() - create broadcast protocol message
1477 static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
1479 struct sk_buff_head *xmitq)
1481 struct sk_buff *skb;
1482 struct tipc_msg *hdr;
1483 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
1484 u16 ack = l->rcv_nxt - 1;
1485 u16 gap_to = peers_snd_nxt - 1;
1487 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
1488 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
1492 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1493 msg_set_bcast_ack(hdr, ack);
1494 msg_set_bcgap_after(hdr, ack);
1496 gap_to = buf_seqno(dfrd_skb) - 1;
1497 msg_set_bcgap_to(hdr, gap_to);
1498 msg_set_non_seq(hdr, bcast);
1499 __skb_queue_tail(xmitq, skb);
1503 /* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
1505 * Give a newly added peer node the sequence number where it should
1506 * start receiving and acking broadcast packets.
1508 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
1509 struct sk_buff_head *xmitq)
1511 struct sk_buff_head list;
1513 __skb_queue_head_init(&list);
1514 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
1516 tipc_link_xmit(l, &list, xmitq);
1519 /* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
1521 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
1523 int mtyp = msg_type(hdr);
1524 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1529 if (msg_user(hdr) == BCAST_PROTOCOL) {
1530 l->rcv_nxt = peers_snd_nxt;
1531 l->state = LINK_ESTABLISHED;
1535 if (l->peer_caps & TIPC_BCAST_SYNCH)
1538 if (msg_peer_node_is_up(hdr))
1541 /* Compatibility: accept older, less safe initial synch data */
1542 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
1543 l->rcv_nxt = peers_snd_nxt;
1546 /* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
1548 void tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
1549 struct sk_buff_head *xmitq)
1551 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
1556 if (!msg_peer_node_is_up(hdr))
1559 l->bc_peer_is_up = true;
1561 /* Ignore if peers_snd_nxt goes beyond receive window */
1562 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
1565 if (!more(peers_snd_nxt, l->rcv_nxt)) {
1566 l->nack_state = BC_NACK_SND_CONDITIONAL;
1570 /* Don't NACK if one was recently sent or peeked */
1571 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
1572 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1576 /* Conditionally delay NACK sending until next synch rcv */
1577 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
1578 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
1579 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
1583 /* Send NACK now but suppress next one */
1584 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
1585 l->nack_state = BC_NACK_SND_SUPPRESS;
1588 void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
1589 struct sk_buff_head *xmitq)
1591 struct sk_buff *skb, *tmp;
1592 struct tipc_link *snd_l = l->bc_sndlink;
1594 if (!link_is_up(l) || !l->bc_peer_is_up)
1597 if (!more(acked, l->acked))
1600 /* Skip over packets peer has already acked */
1601 skb_queue_walk(&snd_l->transmq, skb) {
1602 if (more(buf_seqno(skb), l->acked))
1606 /* Update/release the packets peer is acking now */
1607 skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) {
1608 if (more(buf_seqno(skb), acked))
1610 if (!--TIPC_SKB_CB(skb)->ackers) {
1611 __skb_unlink(skb, &snd_l->transmq);
1616 tipc_link_advance_backlog(snd_l, xmitq);
1617 if (unlikely(!skb_queue_empty(&snd_l->wakeupq)))
1618 link_prepare_wakeup(snd_l);
1621 /* tipc_link_bc_nack_rcv(): receive broadcast nack message
1623 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
1624 struct sk_buff_head *xmitq)
1626 struct tipc_msg *hdr = buf_msg(skb);
1627 u32 dnode = msg_destnode(hdr);
1628 int mtyp = msg_type(hdr);
1629 u16 acked = msg_bcast_ack(hdr);
1630 u16 from = acked + 1;
1631 u16 to = msg_bcgap_to(hdr);
1632 u16 peers_snd_nxt = to + 1;
1637 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
1640 if (mtyp != STATE_MSG)
1643 if (dnode == tipc_own_addr(l->net)) {
1644 tipc_link_bc_ack_rcv(l, acked, xmitq);
1645 rc = tipc_link_retrans(l->bc_sndlink, from, to, xmitq);
1646 l->stats.recv_nacks++;
1650 /* Msg for other node => suppress own NACK at next sync if applicable */
1651 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
1652 l->nack_state = BC_NACK_SND_SUPPRESS;
1657 void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
1659 int max_bulk = TIPC_MAX_PUBLICATIONS / (l->mtu / ITEM_SIZE);
1662 l->backlog[TIPC_LOW_IMPORTANCE].limit = win / 2;
1663 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = win;
1664 l->backlog[TIPC_HIGH_IMPORTANCE].limit = win / 2 * 3;
1665 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = win * 2;
1666 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
1670 * link_reset_stats - reset link statistics
1671 * @l: pointer to link
1673 void tipc_link_reset_stats(struct tipc_link *l)
1675 memset(&l->stats, 0, sizeof(l->stats));
1676 if (!link_is_bc_sndlink(l)) {
1677 l->stats.sent_info = l->snd_nxt;
1678 l->stats.recv_info = l->rcv_nxt;
1682 static void link_print(struct tipc_link *l, const char *str)
1684 struct sk_buff *hskb = skb_peek(&l->transmq);
1685 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
1686 u16 tail = l->snd_nxt - 1;
1688 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
1689 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
1690 skb_queue_len(&l->transmq), head, tail,
1691 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
1694 /* Parse and validate nested (link) properties valid for media, bearer and link
1696 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
1700 err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
1701 tipc_nl_prop_policy);
1705 if (props[TIPC_NLA_PROP_PRIO]) {
1708 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
1709 if (prio > TIPC_MAX_LINK_PRI)
1713 if (props[TIPC_NLA_PROP_TOL]) {
1716 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
1717 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
1721 if (props[TIPC_NLA_PROP_WIN]) {
1724 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
1725 if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
1732 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
1735 struct nlattr *stats;
1742 struct nla_map map[] = {
1743 {TIPC_NLA_STATS_RX_INFO, s->recv_info},
1744 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
1745 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
1746 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
1747 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
1748 {TIPC_NLA_STATS_TX_INFO, s->sent_info},
1749 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
1750 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
1751 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
1752 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
1753 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
1754 s->msg_length_counts : 1},
1755 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
1756 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
1757 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
1758 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
1759 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
1760 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
1761 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
1762 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
1763 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
1764 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
1765 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
1766 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
1767 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
1768 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
1769 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
1770 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
1771 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
1772 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
1773 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
1774 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
1775 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
1776 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
1777 (s->accu_queue_sz / s->queue_sz_counts) : 0}
1780 stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1784 for (i = 0; i < ARRAY_SIZE(map); i++)
1785 if (nla_put_u32(skb, map[i].key, map[i].val))
1788 nla_nest_end(skb, stats);
1792 nla_nest_cancel(skb, stats);
1797 /* Caller should hold appropriate locks to protect the link */
1798 int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
1799 struct tipc_link *link, int nlflags)
1803 struct nlattr *attrs;
1804 struct nlattr *prop;
1805 struct tipc_net *tn = net_generic(net, tipc_net_id);
1807 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1808 nlflags, TIPC_NL_LINK_GET);
1812 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1816 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
1818 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST,
1819 tipc_cluster_mask(tn->own_addr)))
1821 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
1823 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->rcv_nxt))
1825 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->snd_nxt))
1828 if (tipc_link_is_up(link))
1829 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1832 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
1835 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1838 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1840 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
1842 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
1845 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
1847 nla_nest_end(msg->skb, prop);
1849 err = __tipc_nl_add_stats(msg->skb, &link->stats);
1853 nla_nest_end(msg->skb, attrs);
1854 genlmsg_end(msg->skb, hdr);
1859 nla_nest_cancel(msg->skb, prop);
1861 nla_nest_cancel(msg->skb, attrs);
1863 genlmsg_cancel(msg->skb, hdr);
1868 static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
1869 struct tipc_stats *stats)
1872 struct nlattr *nest;
1879 struct nla_map map[] = {
1880 {TIPC_NLA_STATS_RX_INFO, stats->recv_info},
1881 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
1882 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
1883 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
1884 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
1885 {TIPC_NLA_STATS_TX_INFO, stats->sent_info},
1886 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
1887 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
1888 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
1889 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
1890 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
1891 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
1892 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
1893 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
1894 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
1895 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
1896 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
1897 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
1898 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
1899 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
1902 nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
1906 for (i = 0; i < ARRAY_SIZE(map); i++)
1907 if (nla_put_u32(skb, map[i].key, map[i].val))
1910 nla_nest_end(skb, nest);
1914 nla_nest_cancel(skb, nest);
1919 int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
1923 struct nlattr *attrs;
1924 struct nlattr *prop;
1925 struct tipc_net *tn = net_generic(net, tipc_net_id);
1926 struct tipc_link *bcl = tn->bcl;
1931 tipc_bcast_lock(net);
1933 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
1934 NLM_F_MULTI, TIPC_NL_LINK_GET);
1936 tipc_bcast_unlock(net);
1940 attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
1944 /* The broadcast link is always up */
1945 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
1948 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
1950 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
1952 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, bcl->rcv_nxt))
1954 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, bcl->snd_nxt))
1957 prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
1960 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
1962 nla_nest_end(msg->skb, prop);
1964 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
1968 tipc_bcast_unlock(net);
1969 nla_nest_end(msg->skb, attrs);
1970 genlmsg_end(msg->skb, hdr);
1975 nla_nest_cancel(msg->skb, prop);
1977 nla_nest_cancel(msg->skb, attrs);
1979 tipc_bcast_unlock(net);
1980 genlmsg_cancel(msg->skb, hdr);
1985 void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
1986 struct sk_buff_head *xmitq)
1989 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, tol, 0, xmitq);
1992 void tipc_link_set_prio(struct tipc_link *l, u32 prio,
1993 struct sk_buff_head *xmitq)
1996 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, prio, xmitq);
1999 void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2001 l->abort_limit = limit;