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
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9 * modification, are permitted provided that the following conditions are met:
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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.
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42 #include "name_distr.h"
49 #include <linux/pkt_sched.h>
70 u32 link_congs; /* # port sends blocked by congestion */
73 u32 max_queue_sz; /* send queue size high water mark */
74 u32 accu_queue_sz; /* used for send queue size profiling */
75 u32 queue_sz_counts; /* used for send queue size profiling */
76 u32 msg_length_counts; /* used for message length profiling */
77 u32 msg_lengths_total; /* used for message length profiling */
78 u32 msg_length_profile[7]; /* used for msg. length profiling */
82 * struct tipc_link - TIPC link data structure
83 * @addr: network address of link's peer node
84 * @name: link name character string
85 * @media_addr: media address to use when sending messages over link
87 * @net: pointer to namespace struct
88 * @refcnt: reference counter for permanent references (owner node & timer)
89 * @peer_session: link session # being used by peer end of link
90 * @peer_bearer_id: bearer id used by link's peer endpoint
91 * @bearer_id: local bearer id used by link
92 * @tolerance: minimum link continuity loss needed to reset link [in ms]
93 * @abort_limit: # of unacknowledged continuity probes needed to reset link
94 * @state: current state of link FSM
95 * @peer_caps: bitmap describing capabilities of peer node
96 * @silent_intv_cnt: # of timer intervals without any reception from peer
97 * @proto_msg: template for control messages generated by link
98 * @pmsg: convenience pointer to "proto_msg" field
99 * @priority: current link priority
100 * @net_plane: current link network plane ('A' through 'H')
101 * @mon_state: cookie with information needed by link monitor
102 * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
103 * @exp_msg_count: # of tunnelled messages expected during link changeover
104 * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
105 * @mtu: current maximum packet size for this link
106 * @advertised_mtu: advertised own mtu when link is being established
107 * @transmitq: queue for sent, non-acked messages
108 * @backlogq: queue for messages waiting to be sent
109 * @snt_nxt: next sequence number to use for outbound messages
110 * @ackers: # of peers that needs to ack each packet before it can be released
111 * @acked: # last packet acked by a certain peer. Used for broadcast.
112 * @rcv_nxt: next sequence number to expect for inbound messages
113 * @deferred_queue: deferred queue saved OOS b'cast message received from node
114 * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
115 * @inputq: buffer queue for messages to be delivered upwards
116 * @namedq: buffer queue for name table messages to be delivered upwards
117 * @next_out: ptr to first unsent outbound message in queue
118 * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
119 * @long_msg_seq_no: next identifier to use for outbound fragmented messages
120 * @reasm_buf: head of partially reassembled inbound message fragments
121 * @bc_rcvr: marks that this is a broadcast receiver link
122 * @stats: collects statistics regarding link activity
123 * @session: session to be used by link
124 * @snd_nxt_state: next send seq number
125 * @rcv_nxt_state: next rcv seq number
126 * @in_session: have received ACTIVATE_MSG from peer
127 * @active: link is active
128 * @if_name: associated interface name
129 * @rst_cnt: link reset counter
130 * @drop_point: seq number for failover handling (FIXME)
131 * @failover_reasm_skb: saved failover msg ptr (FIXME)
132 * @failover_deferdq: deferred message queue for failover processing (FIXME)
133 * @transmq: the link's transmit queue
134 * @backlog: link's backlog by priority (importance)
135 * @snd_nxt: next sequence number to be used
136 * @rcv_unacked: # messages read by user, but not yet acked back to peer
137 * @deferdq: deferred receive queue
138 * @window: sliding window size for congestion handling
139 * @min_win: minimal send window to be used by link
140 * @ssthresh: slow start threshold for congestion handling
141 * @max_win: maximal send window to be used by link
142 * @cong_acks: congestion acks for congestion avoidance (FIXME)
143 * @checkpoint: seq number for congestion window size handling
144 * @reasm_tnlmsg: fragmentation/reassembly area for tunnel protocol message
145 * @last_gap: last gap ack blocks for bcast (FIXME)
146 * @last_ga: ptr to gap ack blocks
147 * @bc_rcvlink: the peer specific link used for broadcast reception
148 * @bc_sndlink: the namespace global link used for broadcast sending
149 * @nack_state: bcast nack state
150 * @bc_peer_is_up: peer has acked the bcast init msg
154 char name[TIPC_MAX_LINK_NAME];
157 /* Management and link supervision data */
171 char if_name[TIPC_MAX_IF_NAME];
174 struct tipc_mon_state mon_state;
179 struct sk_buff *failover_reasm_skb;
180 struct sk_buff_head failover_deferdq;
182 /* Max packet negotiation */
187 struct sk_buff_head transmq;
188 struct sk_buff_head backlogq;
192 struct sk_buff *target_bskb;
199 struct sk_buff_head deferdq;
200 struct sk_buff_head *inputq;
201 struct sk_buff_head *namedq;
203 /* Congestion handling */
204 struct sk_buff_head wakeupq;
212 /* Fragmentation/reassembly */
213 struct sk_buff *reasm_buf;
214 struct sk_buff *reasm_tnlmsg;
220 struct tipc_gap_ack_blks *last_ga;
221 struct tipc_link *bc_rcvlink;
222 struct tipc_link *bc_sndlink;
227 struct tipc_stats stats;
231 * Error message prefixes
233 static const char *link_co_err = "Link tunneling error, ";
234 static const char *link_rst_msg = "Resetting link ";
236 /* Send states for broadcast NACKs
239 BC_NACK_SND_CONDITIONAL,
240 BC_NACK_SND_UNCONDITIONAL,
241 BC_NACK_SND_SUPPRESS,
244 #define TIPC_BC_RETR_LIM (jiffies + msecs_to_jiffies(10))
245 #define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
250 LINK_ESTABLISHED = 0xe,
251 LINK_ESTABLISHING = 0xe << 4,
252 LINK_RESET = 0x1 << 8,
253 LINK_RESETTING = 0x2 << 12,
254 LINK_PEER_RESET = 0xd << 16,
255 LINK_FAILINGOVER = 0xf << 20,
256 LINK_SYNCHING = 0xc << 24
259 /* Link FSM state checking routines
261 static int link_is_up(struct tipc_link *l)
263 return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
266 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
267 struct sk_buff_head *xmitq);
268 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
269 bool probe_reply, u16 rcvgap,
270 int tolerance, int priority,
271 struct sk_buff_head *xmitq);
272 static void link_print(struct tipc_link *l, const char *str);
273 static int tipc_link_build_nack_msg(struct tipc_link *l,
274 struct sk_buff_head *xmitq);
275 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
276 struct sk_buff_head *xmitq);
277 static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
278 struct tipc_link *l, u8 start_index);
279 static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
280 static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
282 struct tipc_gap_ack_blks *ga,
283 struct sk_buff_head *xmitq,
284 bool *retransmitted, int *rc);
285 static void tipc_link_update_cwin(struct tipc_link *l, int released,
288 * Simple non-static link routines (i.e. referenced outside this file)
290 bool tipc_link_is_up(struct tipc_link *l)
292 return link_is_up(l);
295 bool tipc_link_peer_is_down(struct tipc_link *l)
297 return l->state == LINK_PEER_RESET;
300 bool tipc_link_is_reset(struct tipc_link *l)
302 return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING);
305 bool tipc_link_is_establishing(struct tipc_link *l)
307 return l->state == LINK_ESTABLISHING;
310 bool tipc_link_is_synching(struct tipc_link *l)
312 return l->state == LINK_SYNCHING;
315 bool tipc_link_is_failingover(struct tipc_link *l)
317 return l->state == LINK_FAILINGOVER;
320 bool tipc_link_is_blocked(struct tipc_link *l)
322 return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
325 static bool link_is_bc_sndlink(struct tipc_link *l)
327 return !l->bc_sndlink;
330 static bool link_is_bc_rcvlink(struct tipc_link *l)
332 return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
335 void tipc_link_set_active(struct tipc_link *l, bool active)
340 u32 tipc_link_id(struct tipc_link *l)
342 return l->peer_bearer_id << 16 | l->bearer_id;
345 int tipc_link_min_win(struct tipc_link *l)
350 int tipc_link_max_win(struct tipc_link *l)
355 int tipc_link_prio(struct tipc_link *l)
360 unsigned long tipc_link_tolerance(struct tipc_link *l)
365 struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
370 char tipc_link_plane(struct tipc_link *l)
375 struct net *tipc_link_net(struct tipc_link *l)
380 void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
382 l->peer_caps = capabilities;
385 void tipc_link_add_bc_peer(struct tipc_link *snd_l,
386 struct tipc_link *uc_l,
387 struct sk_buff_head *xmitq)
389 struct tipc_link *rcv_l = uc_l->bc_rcvlink;
392 rcv_l->acked = snd_l->snd_nxt - 1;
393 snd_l->state = LINK_ESTABLISHED;
394 tipc_link_build_bc_init_msg(uc_l, xmitq);
397 void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
398 struct tipc_link *rcv_l,
399 struct sk_buff_head *xmitq)
401 u16 ack = snd_l->snd_nxt - 1;
404 rcv_l->bc_peer_is_up = true;
405 rcv_l->state = LINK_ESTABLISHED;
406 tipc_link_bc_ack_rcv(rcv_l, ack, 0, NULL, xmitq, NULL);
407 trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
408 tipc_link_reset(rcv_l);
409 rcv_l->state = LINK_RESET;
410 if (!snd_l->ackers) {
411 trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero ackers!");
412 tipc_link_reset(snd_l);
413 snd_l->state = LINK_RESET;
414 __skb_queue_purge(xmitq);
418 int tipc_link_bc_peers(struct tipc_link *l)
423 static u16 link_bc_rcv_gap(struct tipc_link *l)
425 struct sk_buff *skb = skb_peek(&l->deferdq);
428 if (more(l->snd_nxt, l->rcv_nxt))
429 gap = l->snd_nxt - l->rcv_nxt;
431 gap = buf_seqno(skb) - l->rcv_nxt;
435 void tipc_link_set_mtu(struct tipc_link *l, int mtu)
440 int tipc_link_mtu(struct tipc_link *l)
445 int tipc_link_mss(struct tipc_link *l)
447 #ifdef CONFIG_TIPC_CRYPTO
448 return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
450 return l->mtu - INT_H_SIZE;
454 u16 tipc_link_rcv_nxt(struct tipc_link *l)
459 u16 tipc_link_acked(struct tipc_link *l)
464 char *tipc_link_name(struct tipc_link *l)
469 u32 tipc_link_state(struct tipc_link *l)
475 * tipc_link_create - create a new link
476 * @net: pointer to associated network namespace
477 * @if_name: associated interface name
478 * @bearer_id: id (index) of associated bearer
479 * @tolerance: link tolerance to be used by link
480 * @net_plane: network plane (A,B,c..) this link belongs to
481 * @mtu: mtu to be advertised by link
482 * @priority: priority to be used by link
483 * @min_win: minimal send window to be used by link
484 * @max_win: maximal send window to be used by link
485 * @session: session to be used by link
486 * @peer: node id of peer node
487 * @peer_caps: bitmap describing peer node capabilities
488 * @bc_sndlink: the namespace global link used for broadcast sending
489 * @bc_rcvlink: the peer specific link used for broadcast reception
490 * @inputq: queue to put messages ready for delivery
491 * @namedq: queue to put binding table update messages ready for delivery
492 * @link: return value, pointer to put the created link
493 * @self: local unicast link id
494 * @peer_id: 128-bit ID of peer
496 * Return: true if link was created, otherwise false
498 bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
499 int tolerance, char net_plane, u32 mtu, int priority,
500 u32 min_win, u32 max_win, u32 session, u32 self,
501 u32 peer, u8 *peer_id, u16 peer_caps,
502 struct tipc_link *bc_sndlink,
503 struct tipc_link *bc_rcvlink,
504 struct sk_buff_head *inputq,
505 struct sk_buff_head *namedq,
506 struct tipc_link **link)
508 char peer_str[NODE_ID_STR_LEN] = {0,};
509 char self_str[NODE_ID_STR_LEN] = {0,};
512 l = kzalloc(sizeof(*l), GFP_ATOMIC);
516 l->session = session;
518 /* Set link name for unicast links only */
520 tipc_nodeid2string(self_str, tipc_own_id(net));
521 if (strlen(self_str) > 16)
522 sprintf(self_str, "%x", self);
523 tipc_nodeid2string(peer_str, peer_id);
524 if (strlen(peer_str) > 16)
525 sprintf(peer_str, "%x", peer);
527 /* Peer i/f name will be completed by reset/activate message */
528 snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
529 self_str, if_name, peer_str);
531 strcpy(l->if_name, if_name);
533 l->peer_caps = peer_caps;
535 l->in_session = false;
536 l->bearer_id = bearer_id;
537 l->tolerance = tolerance;
539 bc_rcvlink->tolerance = tolerance;
540 l->net_plane = net_plane;
541 l->advertised_mtu = mtu;
543 l->priority = priority;
544 tipc_link_set_queue_limits(l, min_win, max_win);
546 l->bc_sndlink = bc_sndlink;
547 l->bc_rcvlink = bc_rcvlink;
550 l->state = LINK_RESETTING;
551 __skb_queue_head_init(&l->transmq);
552 __skb_queue_head_init(&l->backlogq);
553 __skb_queue_head_init(&l->deferdq);
554 __skb_queue_head_init(&l->failover_deferdq);
555 skb_queue_head_init(&l->wakeupq);
556 skb_queue_head_init(l->inputq);
561 * tipc_link_bc_create - create new link to be used for broadcast
562 * @net: pointer to associated network namespace
563 * @mtu: mtu to be used initially if no peers
564 * @min_win: minimal send window to be used by link
565 * @max_win: maximal send window to be used by link
566 * @inputq: queue to put messages ready for delivery
567 * @namedq: queue to put binding table update messages ready for delivery
568 * @link: return value, pointer to put the created link
569 * @ownnode: identity of own node
570 * @peer: node id of peer node
571 * @peer_id: 128-bit ID of peer
572 * @peer_caps: bitmap describing peer node capabilities
573 * @bc_sndlink: the namespace global link used for broadcast sending
575 * Return: true if link was created, otherwise false
577 bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer, u8 *peer_id,
578 int mtu, u32 min_win, u32 max_win, u16 peer_caps,
579 struct sk_buff_head *inputq,
580 struct sk_buff_head *namedq,
581 struct tipc_link *bc_sndlink,
582 struct tipc_link **link)
586 if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, min_win,
587 max_win, 0, ownnode, peer, NULL, peer_caps,
588 bc_sndlink, NULL, inputq, namedq, link))
593 char peer_str[NODE_ID_STR_LEN] = {0,};
595 tipc_nodeid2string(peer_str, peer_id);
596 if (strlen(peer_str) > 16)
597 sprintf(peer_str, "%x", peer);
598 /* Broadcast receiver link name: "broadcast-link:<peer>" */
599 snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
602 strcpy(l->name, tipc_bclink_name);
604 trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
606 l->state = LINK_RESET;
610 /* Broadcast send link is always up */
611 if (link_is_bc_sndlink(l))
612 l->state = LINK_ESTABLISHED;
614 /* Disable replicast if even a single peer doesn't support it */
615 if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
616 tipc_bcast_toggle_rcast(net, false);
622 * tipc_link_fsm_evt - link finite state machine
623 * @l: pointer to link
624 * @evt: state machine event to be processed
626 int tipc_link_fsm_evt(struct tipc_link *l, int evt)
629 int old_state = l->state;
634 case LINK_PEER_RESET_EVT:
635 l->state = LINK_PEER_RESET;
638 l->state = LINK_RESET;
640 case LINK_FAILURE_EVT:
641 case LINK_FAILOVER_BEGIN_EVT:
642 case LINK_ESTABLISH_EVT:
643 case LINK_FAILOVER_END_EVT:
644 case LINK_SYNCH_BEGIN_EVT:
645 case LINK_SYNCH_END_EVT:
652 case LINK_PEER_RESET_EVT:
653 l->state = LINK_ESTABLISHING;
655 case LINK_FAILOVER_BEGIN_EVT:
656 l->state = LINK_FAILINGOVER;
657 case LINK_FAILURE_EVT:
659 case LINK_ESTABLISH_EVT:
660 case LINK_FAILOVER_END_EVT:
662 case LINK_SYNCH_BEGIN_EVT:
663 case LINK_SYNCH_END_EVT:
668 case LINK_PEER_RESET:
671 l->state = LINK_ESTABLISHING;
673 case LINK_PEER_RESET_EVT:
674 case LINK_ESTABLISH_EVT:
675 case LINK_FAILURE_EVT:
677 case LINK_SYNCH_BEGIN_EVT:
678 case LINK_SYNCH_END_EVT:
679 case LINK_FAILOVER_BEGIN_EVT:
680 case LINK_FAILOVER_END_EVT:
685 case LINK_FAILINGOVER:
687 case LINK_FAILOVER_END_EVT:
688 l->state = LINK_RESET;
690 case LINK_PEER_RESET_EVT:
692 case LINK_ESTABLISH_EVT:
693 case LINK_FAILURE_EVT:
695 case LINK_FAILOVER_BEGIN_EVT:
696 case LINK_SYNCH_BEGIN_EVT:
697 case LINK_SYNCH_END_EVT:
702 case LINK_ESTABLISHING:
704 case LINK_ESTABLISH_EVT:
705 l->state = LINK_ESTABLISHED;
707 case LINK_FAILOVER_BEGIN_EVT:
708 l->state = LINK_FAILINGOVER;
711 l->state = LINK_RESET;
713 case LINK_FAILURE_EVT:
714 case LINK_PEER_RESET_EVT:
715 case LINK_SYNCH_BEGIN_EVT:
716 case LINK_FAILOVER_END_EVT:
718 case LINK_SYNCH_END_EVT:
723 case LINK_ESTABLISHED:
725 case LINK_PEER_RESET_EVT:
726 l->state = LINK_PEER_RESET;
727 rc |= TIPC_LINK_DOWN_EVT;
729 case LINK_FAILURE_EVT:
730 l->state = LINK_RESETTING;
731 rc |= TIPC_LINK_DOWN_EVT;
734 l->state = LINK_RESET;
736 case LINK_ESTABLISH_EVT:
737 case LINK_SYNCH_END_EVT:
739 case LINK_SYNCH_BEGIN_EVT:
740 l->state = LINK_SYNCHING;
742 case LINK_FAILOVER_BEGIN_EVT:
743 case LINK_FAILOVER_END_EVT:
750 case LINK_PEER_RESET_EVT:
751 l->state = LINK_PEER_RESET;
752 rc |= TIPC_LINK_DOWN_EVT;
754 case LINK_FAILURE_EVT:
755 l->state = LINK_RESETTING;
756 rc |= TIPC_LINK_DOWN_EVT;
759 l->state = LINK_RESET;
761 case LINK_ESTABLISH_EVT:
762 case LINK_SYNCH_BEGIN_EVT:
764 case LINK_SYNCH_END_EVT:
765 l->state = LINK_ESTABLISHED;
767 case LINK_FAILOVER_BEGIN_EVT:
768 case LINK_FAILOVER_END_EVT:
774 pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
776 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
779 pr_err("Illegal FSM event %x in state %x on link %s\n",
780 evt, l->state, l->name);
781 trace_tipc_link_fsm(l->name, old_state, l->state, evt);
785 /* link_profile_stats - update statistical profiling of traffic
787 static void link_profile_stats(struct tipc_link *l)
790 struct tipc_msg *msg;
793 /* Update counters used in statistical profiling of send traffic */
794 l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
795 l->stats.queue_sz_counts++;
797 skb = skb_peek(&l->transmq);
801 length = msg_size(msg);
803 if (msg_user(msg) == MSG_FRAGMENTER) {
804 if (msg_type(msg) != FIRST_FRAGMENT)
806 length = msg_size(msg_inner_hdr(msg));
808 l->stats.msg_lengths_total += length;
809 l->stats.msg_length_counts++;
811 l->stats.msg_length_profile[0]++;
812 else if (length <= 256)
813 l->stats.msg_length_profile[1]++;
814 else if (length <= 1024)
815 l->stats.msg_length_profile[2]++;
816 else if (length <= 4096)
817 l->stats.msg_length_profile[3]++;
818 else if (length <= 16384)
819 l->stats.msg_length_profile[4]++;
820 else if (length <= 32768)
821 l->stats.msg_length_profile[5]++;
823 l->stats.msg_length_profile[6]++;
827 * tipc_link_too_silent - check if link is "too silent"
828 * @l: tipc link to be checked
830 * Return: true if the link 'silent_intv_cnt' is about to reach the
831 * 'abort_limit' value, otherwise false
833 bool tipc_link_too_silent(struct tipc_link *l)
835 return (l->silent_intv_cnt + 2 > l->abort_limit);
838 /* tipc_link_timeout - perform periodic task as instructed from node timeout
840 int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
847 u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
848 u16 bc_acked = l->bc_rcvlink->acked;
849 struct tipc_mon_state *mstate = &l->mon_state;
851 trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
852 trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
854 case LINK_ESTABLISHED:
857 link_profile_stats(l);
858 tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
859 if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
860 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
861 state = bc_acked != bc_snt;
862 state |= l->bc_rcvlink->rcv_unacked;
863 state |= l->rcv_unacked;
864 state |= !skb_queue_empty(&l->transmq);
865 probe = mstate->probing;
866 probe |= l->silent_intv_cnt;
867 if (probe || mstate->monitoring)
868 l->silent_intv_cnt++;
869 probe |= !skb_queue_empty(&l->deferdq);
870 if (l->snd_nxt == l->checkpoint) {
871 tipc_link_update_cwin(l, 0, 0);
874 l->checkpoint = l->snd_nxt;
877 setup = l->rst_cnt++ <= 4;
878 setup |= !(l->rst_cnt % 16);
881 case LINK_ESTABLISHING:
885 case LINK_PEER_RESET:
887 case LINK_FAILINGOVER:
893 if (state || probe || setup)
894 tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
900 * link_schedule_user - schedule a message sender for wakeup after congestion
902 * @hdr: header of message that is being sent
903 * Create pseudo msg to send back to user when congestion abates
905 static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
907 u32 dnode = tipc_own_addr(l->net);
908 u32 dport = msg_origport(hdr);
911 /* Create and schedule wakeup pseudo message */
912 skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
913 dnode, l->addr, dport, 0, 0);
916 msg_set_dest_droppable(buf_msg(skb), true);
917 TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
918 skb_queue_tail(&l->wakeupq, skb);
919 l->stats.link_congs++;
920 trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
925 * link_prepare_wakeup - prepare users for wakeup after congestion
927 * Wake up a number of waiting users, as permitted by available space
930 static void link_prepare_wakeup(struct tipc_link *l)
932 struct sk_buff_head *wakeupq = &l->wakeupq;
933 struct sk_buff_head *inputq = l->inputq;
934 struct sk_buff *skb, *tmp;
935 struct sk_buff_head tmpq;
939 __skb_queue_head_init(&tmpq);
941 for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
942 avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
944 skb_queue_walk_safe(wakeupq, skb, tmp) {
945 imp = TIPC_SKB_CB(skb)->chain_imp;
949 __skb_unlink(skb, wakeupq);
950 __skb_queue_tail(&tmpq, skb);
953 spin_lock_bh(&inputq->lock);
954 skb_queue_splice_tail(&tmpq, inputq);
955 spin_unlock_bh(&inputq->lock);
960 * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
961 * the given skb should be next attempted
962 * @skb: skb to set a future retransmission time for
963 * @l: link the skb will be transmitted on
965 static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
968 if (link_is_bc_sndlink(l))
969 TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
971 TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
974 void tipc_link_reset(struct tipc_link *l)
976 struct sk_buff_head list;
979 __skb_queue_head_init(&list);
981 l->in_session = false;
982 /* Force re-synch of peer session number before establishing */
985 l->mtu = l->advertised_mtu;
987 spin_lock_bh(&l->wakeupq.lock);
988 skb_queue_splice_init(&l->wakeupq, &list);
989 spin_unlock_bh(&l->wakeupq.lock);
991 spin_lock_bh(&l->inputq->lock);
992 skb_queue_splice_init(&list, l->inputq);
993 spin_unlock_bh(&l->inputq->lock);
995 __skb_queue_purge(&l->transmq);
996 __skb_queue_purge(&l->deferdq);
997 __skb_queue_purge(&l->backlogq);
998 __skb_queue_purge(&l->failover_deferdq);
999 for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
1000 l->backlog[imp].len = 0;
1001 l->backlog[imp].target_bskb = NULL;
1003 kfree_skb(l->reasm_buf);
1004 kfree_skb(l->reasm_tnlmsg);
1005 kfree_skb(l->failover_reasm_skb);
1006 l->reasm_buf = NULL;
1007 l->reasm_tnlmsg = NULL;
1008 l->failover_reasm_skb = NULL;
1012 l->snd_nxt_state = 1;
1013 l->rcv_nxt_state = 1;
1018 l->silent_intv_cnt = 0;
1020 l->bc_peer_is_up = false;
1021 memset(&l->mon_state, 0, sizeof(l->mon_state));
1022 tipc_link_reset_stats(l);
1026 * tipc_link_xmit(): enqueue buffer list according to queue situation
1028 * @list: chain of buffers containing message
1029 * @xmitq: returned list of packets to be sent by caller
1031 * Consumes the buffer chain.
1032 * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted
1033 * Return: 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS
1035 int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list,
1036 struct sk_buff_head *xmitq)
1038 struct sk_buff_head *backlogq = &l->backlogq;
1039 struct sk_buff_head *transmq = &l->transmq;
1040 struct sk_buff *skb, *_skb;
1041 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1042 u16 ack = l->rcv_nxt - 1;
1043 u16 seqno = l->snd_nxt;
1044 int pkt_cnt = skb_queue_len(list);
1045 unsigned int mss = tipc_link_mss(l);
1046 unsigned int cwin = l->window;
1047 unsigned int mtu = l->mtu;
1048 struct tipc_msg *hdr;
1056 hdr = buf_msg(skb_peek(list));
1057 if (unlikely(msg_size(hdr) > mtu)) {
1058 pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
1059 skb_queue_len(list), msg_user(hdr),
1060 msg_type(hdr), msg_size(hdr), mtu);
1061 __skb_queue_purge(list);
1065 imp = msg_importance(hdr);
1066 /* Allow oversubscription of one data msg per source at congestion */
1067 if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
1068 if (imp == TIPC_SYSTEM_IMPORTANCE) {
1069 pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
1072 rc = link_schedule_user(l, hdr);
1076 l->stats.sent_fragmented++;
1077 l->stats.sent_fragments += pkt_cnt;
1080 /* Prepare each packet for sending, and add to relevant queue: */
1081 while ((skb = __skb_dequeue(list))) {
1082 if (likely(skb_queue_len(transmq) < cwin)) {
1084 msg_set_seqno(hdr, seqno);
1085 msg_set_ack(hdr, ack);
1086 msg_set_bcast_ack(hdr, bc_ack);
1087 _skb = skb_clone(skb, GFP_ATOMIC);
1090 __skb_queue_purge(list);
1093 __skb_queue_tail(transmq, skb);
1094 tipc_link_set_skb_retransmit_time(skb, l);
1095 __skb_queue_tail(xmitq, _skb);
1096 TIPC_SKB_CB(skb)->ackers = l->ackers;
1098 l->stats.sent_pkts++;
1102 if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
1103 mss, l->addr, &new_bundle)) {
1105 /* Keep a ref. to the skb for next try */
1106 l->backlog[imp].target_bskb = skb;
1107 l->backlog[imp].len++;
1108 __skb_queue_tail(backlogq, skb);
1111 l->stats.sent_bundles++;
1112 l->stats.sent_bundled++;
1114 l->stats.sent_bundled++;
1118 l->backlog[imp].target_bskb = NULL;
1119 l->backlog[imp].len += (1 + skb_queue_len(list));
1120 __skb_queue_tail(backlogq, skb);
1121 skb_queue_splice_tail_init(list, backlogq);
1127 static void tipc_link_update_cwin(struct tipc_link *l, int released,
1130 int bklog_len = skb_queue_len(&l->backlogq);
1131 struct sk_buff_head *txq = &l->transmq;
1132 int txq_len = skb_queue_len(txq);
1133 u16 cwin = l->window;
1135 /* Enter fast recovery */
1136 if (unlikely(retransmitted)) {
1137 l->ssthresh = max_t(u16, l->window / 2, 300);
1138 l->window = min_t(u16, l->ssthresh, l->window);
1141 /* Enter slow start */
1142 if (unlikely(!released)) {
1143 l->ssthresh = max_t(u16, l->window / 2, 300);
1144 l->window = l->min_win;
1147 /* Don't increase window if no pressure on the transmit queue */
1148 if (txq_len + bklog_len < cwin)
1151 /* Don't increase window if there are holes the transmit queue */
1152 if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
1155 l->cong_acks += released;
1158 if (cwin <= l->ssthresh) {
1159 l->window = min_t(u16, cwin + released, l->max_win);
1162 /* Congestion avoidance */
1163 if (l->cong_acks < cwin)
1165 l->window = min_t(u16, ++cwin, l->max_win);
1169 static void tipc_link_advance_backlog(struct tipc_link *l,
1170 struct sk_buff_head *xmitq)
1172 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1173 struct sk_buff_head *txq = &l->transmq;
1174 struct sk_buff *skb, *_skb;
1175 u16 ack = l->rcv_nxt - 1;
1176 u16 seqno = l->snd_nxt;
1177 struct tipc_msg *hdr;
1178 u16 cwin = l->window;
1181 while (skb_queue_len(txq) < cwin) {
1182 skb = skb_peek(&l->backlogq);
1185 _skb = skb_clone(skb, GFP_ATOMIC);
1188 __skb_dequeue(&l->backlogq);
1190 imp = msg_importance(hdr);
1191 l->backlog[imp].len--;
1192 if (unlikely(skb == l->backlog[imp].target_bskb))
1193 l->backlog[imp].target_bskb = NULL;
1194 __skb_queue_tail(&l->transmq, skb);
1195 tipc_link_set_skb_retransmit_time(skb, l);
1197 __skb_queue_tail(xmitq, _skb);
1198 TIPC_SKB_CB(skb)->ackers = l->ackers;
1199 msg_set_seqno(hdr, seqno);
1200 msg_set_ack(hdr, ack);
1201 msg_set_bcast_ack(hdr, bc_ack);
1203 l->stats.sent_pkts++;
1210 * link_retransmit_failure() - Detect repeated retransmit failures
1211 * @l: tipc link sender
1212 * @r: tipc link receiver (= l in case of unicast)
1213 * @rc: returned code
1215 * Return: true if the repeated retransmit failures happens, otherwise
1218 static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
1221 struct sk_buff *skb = skb_peek(&l->transmq);
1222 struct tipc_msg *hdr;
1227 if (!TIPC_SKB_CB(skb)->retr_cnt)
1230 if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
1231 msecs_to_jiffies(r->tolerance * 10)))
1235 if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
1238 pr_warn("Retransmission failure on link <%s>\n", l->name);
1239 link_print(l, "State of link ");
1240 pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
1241 msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
1242 pr_info("sqno %u, prev: %x, dest: %x\n",
1243 msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
1244 pr_info("retr_stamp %d, retr_cnt %d\n",
1245 jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
1246 TIPC_SKB_CB(skb)->retr_cnt);
1248 trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
1249 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
1250 trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
1252 if (link_is_bc_sndlink(l)) {
1253 r->state = LINK_RESET;
1254 *rc |= TIPC_LINK_DOWN_EVT;
1256 *rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1262 /* tipc_data_input - deliver data and name distr msgs to upper layer
1264 * Consumes buffer if message is of right type
1265 * Node lock must be held
1267 static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
1268 struct sk_buff_head *inputq)
1270 struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
1271 struct tipc_msg *hdr = buf_msg(skb);
1273 switch (msg_user(hdr)) {
1274 case TIPC_LOW_IMPORTANCE:
1275 case TIPC_MEDIUM_IMPORTANCE:
1276 case TIPC_HIGH_IMPORTANCE:
1277 case TIPC_CRITICAL_IMPORTANCE:
1278 if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
1279 skb_queue_tail(mc_inputq, skb);
1284 skb_queue_tail(inputq, skb);
1286 case GROUP_PROTOCOL:
1287 skb_queue_tail(mc_inputq, skb);
1289 case NAME_DISTRIBUTOR:
1290 l->bc_rcvlink->state = LINK_ESTABLISHED;
1291 skb_queue_tail(l->namedq, skb);
1294 case TUNNEL_PROTOCOL:
1295 case MSG_FRAGMENTER:
1296 case BCAST_PROTOCOL:
1298 #ifdef CONFIG_TIPC_CRYPTO
1300 tipc_crypto_msg_rcv(l->net, skb);
1304 pr_warn("Dropping received illegal msg type\n");
1310 /* tipc_link_input - process packet that has passed link protocol check
1314 static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
1315 struct sk_buff_head *inputq,
1316 struct sk_buff **reasm_skb)
1318 struct tipc_msg *hdr = buf_msg(skb);
1319 struct sk_buff *iskb;
1320 struct sk_buff_head tmpq;
1321 int usr = msg_user(hdr);
1324 if (usr == MSG_BUNDLER) {
1325 skb_queue_head_init(&tmpq);
1326 l->stats.recv_bundles++;
1327 l->stats.recv_bundled += msg_msgcnt(hdr);
1328 while (tipc_msg_extract(skb, &iskb, &pos))
1329 tipc_data_input(l, iskb, &tmpq);
1330 tipc_skb_queue_splice_tail(&tmpq, inputq);
1332 } else if (usr == MSG_FRAGMENTER) {
1333 l->stats.recv_fragments++;
1334 if (tipc_buf_append(reasm_skb, &skb)) {
1335 l->stats.recv_fragmented++;
1336 tipc_data_input(l, skb, inputq);
1337 } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
1338 pr_warn_ratelimited("Unable to build fragment list\n");
1339 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1342 } else if (usr == BCAST_PROTOCOL) {
1343 tipc_bcast_lock(l->net);
1344 tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
1345 tipc_bcast_unlock(l->net);
1352 /* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
1353 * inner message along with the ones in the old link's
1356 * @skb: TUNNEL_PROTOCOL message
1357 * @inputq: queue to put messages ready for delivery
1359 static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
1360 struct sk_buff_head *inputq)
1362 struct sk_buff **reasm_skb = &l->failover_reasm_skb;
1363 struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
1364 struct sk_buff_head *fdefq = &l->failover_deferdq;
1365 struct tipc_msg *hdr = buf_msg(skb);
1366 struct sk_buff *iskb;
1371 if (msg_type(hdr) == SYNCH_MSG) {
1376 /* Not a fragment? */
1377 if (likely(!msg_nof_fragms(hdr))) {
1378 if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
1379 pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
1380 skb_queue_len(fdefq));
1385 /* Set fragment type for buf_append */
1386 if (msg_fragm_no(hdr) == 1)
1387 msg_set_type(hdr, FIRST_FRAGMENT);
1388 else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
1389 msg_set_type(hdr, FRAGMENT);
1391 msg_set_type(hdr, LAST_FRAGMENT);
1393 if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
1394 /* Successful but non-complete reassembly? */
1395 if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
1397 pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
1398 return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
1404 seqno = buf_seqno(iskb);
1405 if (unlikely(less(seqno, l->drop_point))) {
1409 if (unlikely(seqno != l->drop_point)) {
1410 __tipc_skb_queue_sorted(fdefq, seqno, iskb);
1415 if (!tipc_data_input(l, iskb, inputq))
1416 rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
1419 } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
1425 * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
1426 * @ga: returned pointer to the Gap ACK blocks if any
1428 * @hdr: the PROTOCOL/STATE_MSG header
1429 * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
1431 * Return: the total Gap ACK blocks size
1433 u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
1434 struct tipc_msg *hdr, bool uc)
1436 struct tipc_gap_ack_blks *p;
1439 /* Does peer support the Gap ACK blocks feature? */
1440 if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
1441 p = (struct tipc_gap_ack_blks *)msg_data(hdr);
1444 if (sz == struct_size(p, gacks, p->ugack_cnt + p->bgack_cnt)) {
1445 /* Good, check if the desired type exists */
1446 if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
1448 /* Backward compatible: peer might not support bc, but uc? */
1449 } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
1456 /* Other cases: ignore! */
1464 static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
1465 struct tipc_link *l, u8 start_index)
1467 struct tipc_gap_ack *gacks = &ga->gacks[start_index];
1468 struct sk_buff *skb = skb_peek(&l->deferdq);
1469 u16 expect, seqno = 0;
1475 expect = buf_seqno(skb);
1476 skb_queue_walk(&l->deferdq, skb) {
1477 seqno = buf_seqno(skb);
1478 if (unlikely(more(seqno, expect))) {
1479 gacks[n].ack = htons(expect - 1);
1480 gacks[n].gap = htons(seqno - expect);
1481 if (++n >= MAX_GAP_ACK_BLKS / 2) {
1482 pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
1484 skb_queue_len(&l->deferdq));
1487 } else if (unlikely(less(seqno, expect))) {
1488 pr_warn("Unexpected skb in deferdq!\n");
1495 gacks[n].ack = htons(seqno);
1501 /* tipc_build_gap_ack_blks - build Gap ACK blocks
1502 * @l: tipc unicast link
1503 * @hdr: the tipc message buffer to store the Gap ACK blocks after built
1505 * The function builds Gap ACK blocks for both the unicast & broadcast receiver
1506 * links of a certain peer, the buffer after built has the network data format
1507 * as found at the struct tipc_gap_ack_blks definition.
1509 * returns the actual allocated memory size
1511 static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
1513 struct tipc_link *bcl = l->bc_rcvlink;
1514 struct tipc_gap_ack_blks *ga;
1517 ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
1519 /* Start with broadcast link first */
1520 tipc_bcast_lock(bcl->net);
1521 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1522 msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
1523 ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
1524 tipc_bcast_unlock(bcl->net);
1526 /* Now for unicast link, but an explicit NACK only (???) */
1527 ga->ugack_cnt = (msg_seq_gap(hdr)) ?
1528 __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
1531 len = struct_size(ga, gacks, ga->bgack_cnt + ga->ugack_cnt);
1532 ga->len = htons(len);
1536 /* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
1537 * acked packets, also doing retransmissions if
1539 * @l: tipc link with transmq queue to be advanced
1540 * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
1541 * @acked: seqno of last packet acked by peer without any gaps before
1542 * @gap: # of gap packets
1543 * @ga: buffer pointer to Gap ACK blocks from peer
1544 * @xmitq: queue for accumulating the retransmitted packets if any
1545 * @retransmitted: returned boolean value if a retransmission is really issued
1546 * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
1547 * happens (- unlikely case)
1549 * Return: the number of packets released from the link transmq
1551 static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
1553 struct tipc_gap_ack_blks *ga,
1554 struct sk_buff_head *xmitq,
1555 bool *retransmitted, int *rc)
1557 struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
1558 struct tipc_gap_ack *gacks = NULL;
1559 struct sk_buff *skb, *_skb, *tmp;
1560 struct tipc_msg *hdr;
1561 u32 qlen = skb_queue_len(&l->transmq);
1562 u16 nacked = acked, ngap = gap, gack_cnt = 0;
1563 u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
1564 u16 ack = l->rcv_nxt - 1;
1566 u16 end = r->acked, start = end, offset = r->last_gap;
1567 u16 si = (last_ga) ? last_ga->start_index : 0;
1568 bool is_uc = !link_is_bc_sndlink(l);
1569 bool bc_has_acked = false;
1571 trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
1573 /* Determine Gap ACK blocks if any for the particular link */
1575 /* Get the Gap ACKs, uc part */
1576 gack_cnt = ga->ugack_cnt;
1577 gacks = &ga->gacks[ga->bgack_cnt];
1579 /* Copy the Gap ACKs, bc part, for later renewal if needed */
1580 this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
1582 if (likely(this_ga)) {
1583 this_ga->start_index = 0;
1584 /* Start with the bc Gap ACKs */
1585 gack_cnt = this_ga->bgack_cnt;
1586 gacks = &this_ga->gacks[0];
1588 /* Hmm, we can get in trouble..., simply ignore it */
1589 pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
1593 /* Advance the link transmq */
1594 skb_queue_walk_safe(&l->transmq, skb, tmp) {
1595 seqno = buf_seqno(skb);
1598 if (less_eq(seqno, nacked)) {
1601 /* Skip packets peer has already acked */
1602 if (!more(seqno, r->acked))
1604 /* Get the next of last Gap ACK blocks */
1605 while (more(seqno, end)) {
1606 if (!last_ga || si >= last_ga->bgack_cnt)
1608 start = end + offset + 1;
1609 end = ntohs(last_ga->gacks[si].ack);
1610 offset = ntohs(last_ga->gacks[si].gap);
1612 WARN_ONCE(more(start, end) ||
1614 si < last_ga->bgack_cnt) ||
1615 si > MAX_GAP_ACK_BLKS,
1616 "Corrupted Gap ACK: %d %d %d %d %d\n",
1617 start, end, offset, si,
1618 last_ga->bgack_cnt);
1620 /* Check against the last Gap ACK block */
1621 if (in_range(seqno, start, end))
1623 /* Update/release the packet peer is acking */
1624 bc_has_acked = true;
1625 if (--TIPC_SKB_CB(skb)->ackers)
1629 __skb_unlink(skb, &l->transmq);
1631 } else if (less_eq(seqno, nacked + ngap)) {
1632 /* First gap: check if repeated retrans failures? */
1633 if (unlikely(seqno == acked + 1 &&
1634 link_retransmit_failure(l, r, rc))) {
1635 /* Ignore this bc Gap ACKs if any */
1640 /* retransmit skb if unrestricted*/
1641 if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
1643 tipc_link_set_skb_retransmit_time(skb, l);
1644 _skb = pskb_copy(skb, GFP_ATOMIC);
1647 hdr = buf_msg(_skb);
1648 msg_set_ack(hdr, ack);
1649 msg_set_bcast_ack(hdr, bc_ack);
1650 _skb->priority = TC_PRIO_CONTROL;
1651 __skb_queue_tail(xmitq, _skb);
1652 l->stats.retransmitted++;
1654 r->stats.retransmitted++;
1655 *retransmitted = true;
1656 /* Increase actual retrans counter & mark first time */
1657 if (!TIPC_SKB_CB(skb)->retr_cnt++)
1658 TIPC_SKB_CB(skb)->retr_stamp = jiffies;
1660 /* retry with Gap ACK blocks if any */
1663 nacked = ntohs(gacks[n].ack);
1664 ngap = ntohs(gacks[n].gap);
1670 /* Renew last Gap ACK blocks for bc if needed */
1674 r->last_ga = this_ga;
1676 } else if (last_ga) {
1677 if (less(acked, start)) {
1679 offset = start - acked - 1;
1680 } else if (less(acked, end)) {
1683 if (si < last_ga->bgack_cnt) {
1684 last_ga->start_index = si;
1685 r->last_gap = offset;
1699 return qlen - skb_queue_len(&l->transmq);
1702 /* tipc_link_build_state_msg: prepare link state message for transmission
1704 * Note that sending of broadcast ack is coordinated among nodes, to reduce
1705 * risk of ack storms towards the sender
1707 int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1712 /* Broadcast ACK must be sent via a unicast link => defer to caller */
1713 if (link_is_bc_rcvlink(l)) {
1714 if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
1718 /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
1719 l->snd_nxt = l->rcv_nxt;
1720 return TIPC_LINK_SND_STATE;
1724 l->stats.sent_acks++;
1725 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
1729 /* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message
1731 void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
1733 int mtyp = RESET_MSG;
1734 struct sk_buff *skb;
1736 if (l->state == LINK_ESTABLISHING)
1737 mtyp = ACTIVATE_MSG;
1739 tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
1741 /* Inform peer that this endpoint is going down if applicable */
1742 skb = skb_peek_tail(xmitq);
1743 if (skb && (l->state == LINK_RESET))
1744 msg_set_peer_stopping(buf_msg(skb), 1);
1747 /* tipc_link_build_nack_msg: prepare link nack message for transmission
1748 * Note that sending of broadcast NACK is coordinated among nodes, to
1749 * reduce the risk of NACK storms towards the sender
1751 static int tipc_link_build_nack_msg(struct tipc_link *l,
1752 struct sk_buff_head *xmitq)
1754 u32 def_cnt = ++l->stats.deferred_recv;
1755 struct sk_buff_head *dfq = &l->deferdq;
1756 u32 defq_len = skb_queue_len(dfq);
1759 if (link_is_bc_rcvlink(l)) {
1760 match1 = def_cnt & 0xf;
1761 match2 = tipc_own_addr(l->net) & 0xf;
1762 if (match1 == match2)
1763 return TIPC_LINK_SND_STATE;
1767 if (defq_len >= 3 && !((defq_len - 3) % 16)) {
1768 u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1770 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
1771 rcvgap, 0, 0, xmitq);
1776 /* tipc_link_rcv - process TIPC packets/messages arriving from off-node
1777 * @l: the link that should handle the message
1779 * @xmitq: queue to place packets to be sent after this call
1781 int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb,
1782 struct sk_buff_head *xmitq)
1784 struct sk_buff_head *defq = &l->deferdq;
1785 struct tipc_msg *hdr = buf_msg(skb);
1786 u16 seqno, rcv_nxt, win_lim;
1790 /* Verify and update link state */
1791 if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
1792 return tipc_link_proto_rcv(l, skb, xmitq);
1794 /* Don't send probe at next timeout expiration */
1795 l->silent_intv_cnt = 0;
1799 seqno = msg_seqno(hdr);
1800 rcv_nxt = l->rcv_nxt;
1801 win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
1803 if (unlikely(!link_is_up(l))) {
1804 if (l->state == LINK_ESTABLISHING)
1805 rc = TIPC_LINK_UP_EVT;
1810 /* Drop if outside receive window */
1811 if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
1812 l->stats.duplicates++;
1816 released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
1817 NULL, NULL, NULL, NULL);
1819 /* Defer delivery if sequence gap */
1820 if (unlikely(seqno != rcv_nxt)) {
1821 if (!__tipc_skb_queue_sorted(defq, seqno, skb))
1822 l->stats.duplicates++;
1823 rc |= tipc_link_build_nack_msg(l, xmitq);
1827 /* Deliver packet */
1829 l->stats.recv_pkts++;
1831 if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
1832 rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
1833 else if (!tipc_data_input(l, skb, l->inputq))
1834 rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
1835 if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
1836 rc |= tipc_link_build_state_msg(l, xmitq);
1837 if (unlikely(rc & ~TIPC_LINK_SND_STATE))
1839 } while ((skb = __tipc_skb_dequeue(defq, l->rcv_nxt)));
1841 /* Forward queues and wake up waiting users */
1843 tipc_link_update_cwin(l, released, 0);
1844 tipc_link_advance_backlog(l, xmitq);
1845 if (unlikely(!skb_queue_empty(&l->wakeupq)))
1846 link_prepare_wakeup(l);
1851 static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
1852 bool probe_reply, u16 rcvgap,
1853 int tolerance, int priority,
1854 struct sk_buff_head *xmitq)
1856 struct tipc_mon_state *mstate = &l->mon_state;
1857 struct sk_buff_head *dfq = &l->deferdq;
1858 struct tipc_link *bcl = l->bc_rcvlink;
1859 struct tipc_msg *hdr;
1860 struct sk_buff *skb;
1861 bool node_up = link_is_up(bcl);
1862 u16 glen = 0, bc_rcvgap = 0;
1866 /* Don't send protocol message during reset or link failover */
1867 if (tipc_link_is_blocked(l))
1870 if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
1873 if ((probe || probe_reply) && !skb_queue_empty(dfq))
1874 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
1876 skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
1877 tipc_max_domain_size + MAX_GAP_ACK_BLKS_SZ,
1878 l->addr, tipc_own_addr(l->net), 0, 0, 0);
1883 data = msg_data(hdr);
1884 msg_set_session(hdr, l->session);
1885 msg_set_bearer_id(hdr, l->bearer_id);
1886 msg_set_net_plane(hdr, l->net_plane);
1887 msg_set_next_sent(hdr, l->snd_nxt);
1888 msg_set_ack(hdr, l->rcv_nxt - 1);
1889 msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
1890 msg_set_bc_ack_invalid(hdr, !node_up);
1891 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
1892 msg_set_link_tolerance(hdr, tolerance);
1893 msg_set_linkprio(hdr, priority);
1894 msg_set_redundant_link(hdr, node_up);
1895 msg_set_seq_gap(hdr, 0);
1896 msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
1898 if (mtyp == STATE_MSG) {
1899 if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
1900 msg_set_seqno(hdr, l->snd_nxt_state++);
1901 msg_set_seq_gap(hdr, rcvgap);
1902 bc_rcvgap = link_bc_rcv_gap(bcl);
1903 msg_set_bc_gap(hdr, bc_rcvgap);
1904 msg_set_probe(hdr, probe);
1905 msg_set_is_keepalive(hdr, probe || probe_reply);
1906 if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
1907 glen = tipc_build_gap_ack_blks(l, hdr);
1908 tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
1909 msg_set_size(hdr, INT_H_SIZE + glen + dlen);
1910 skb_trim(skb, INT_H_SIZE + glen + dlen);
1911 l->stats.sent_states++;
1914 /* RESET_MSG or ACTIVATE_MSG */
1915 if (mtyp == ACTIVATE_MSG) {
1916 msg_set_dest_session_valid(hdr, 1);
1917 msg_set_dest_session(hdr, l->peer_session);
1919 msg_set_max_pkt(hdr, l->advertised_mtu);
1920 strcpy(data, l->if_name);
1921 msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
1922 skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
1925 l->stats.sent_probes++;
1927 l->stats.sent_nacks++;
1929 bcl->stats.sent_nacks++;
1930 skb->priority = TC_PRIO_CONTROL;
1931 __skb_queue_tail(xmitq, skb);
1932 trace_tipc_proto_build(skb, false, l->name);
1935 void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
1936 struct sk_buff_head *xmitq)
1938 u32 onode = tipc_own_addr(l->net);
1939 struct tipc_msg *hdr, *ihdr;
1940 struct sk_buff_head tnlq;
1941 struct sk_buff *skb;
1942 u32 dnode = l->addr;
1944 __skb_queue_head_init(&tnlq);
1945 skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
1946 INT_H_SIZE, BASIC_H_SIZE,
1947 dnode, onode, 0, 0, 0);
1949 pr_warn("%sunable to create tunnel packet\n", link_co_err);
1954 msg_set_msgcnt(hdr, 1);
1955 msg_set_bearer_id(hdr, l->peer_bearer_id);
1957 ihdr = (struct tipc_msg *)msg_data(hdr);
1958 tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
1959 BASIC_H_SIZE, dnode);
1960 msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
1961 __skb_queue_tail(&tnlq, skb);
1962 tipc_link_xmit(l, &tnlq, xmitq);
1965 /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
1966 * with contents of the link's transmit and backlog queues.
1968 void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl,
1969 int mtyp, struct sk_buff_head *xmitq)
1971 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
1972 struct sk_buff *skb, *tnlskb;
1973 struct tipc_msg *hdr, tnlhdr;
1974 struct sk_buff_head *queue = &l->transmq;
1975 struct sk_buff_head tmpxq, tnlq, frags;
1976 u16 pktlen, pktcnt, seqno = l->snd_nxt;
1977 bool pktcnt_need_update = false;
1984 __skb_queue_head_init(&tnlq);
1986 * From now on, send only one single ("dummy") SYNCH message
1987 * to peer. The SYNCH message does not contain any data, just
1988 * a header conveying the synch point to the peer.
1990 if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
1991 tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
1992 INT_H_SIZE, 0, l->addr,
1993 tipc_own_addr(l->net),
1996 pr_warn("%sunable to create dummy SYNCH_MSG\n",
2001 hdr = buf_msg(tnlskb);
2002 syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
2003 msg_set_syncpt(hdr, syncpt);
2004 msg_set_bearer_id(hdr, l->peer_bearer_id);
2005 __skb_queue_tail(&tnlq, tnlskb);
2006 tipc_link_xmit(tnl, &tnlq, xmitq);
2010 __skb_queue_head_init(&tmpxq);
2011 __skb_queue_head_init(&frags);
2012 /* At least one packet required for safe algorithm => add dummy */
2013 skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
2014 BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
2015 0, 0, TIPC_ERR_NO_PORT);
2017 pr_warn("%sunable to create tunnel packet\n", link_co_err);
2020 __skb_queue_tail(&tnlq, skb);
2021 tipc_link_xmit(l, &tnlq, &tmpxq);
2022 __skb_queue_purge(&tmpxq);
2024 /* Initialize reusable tunnel packet header */
2025 tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
2026 mtyp, INT_H_SIZE, l->addr);
2027 if (mtyp == SYNCH_MSG)
2028 pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
2030 pktcnt = skb_queue_len(&l->transmq);
2031 pktcnt += skb_queue_len(&l->backlogq);
2032 msg_set_msgcnt(&tnlhdr, pktcnt);
2033 msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
2035 /* Wrap each packet into a tunnel packet */
2036 skb_queue_walk(queue, skb) {
2038 if (queue == &l->backlogq)
2039 msg_set_seqno(hdr, seqno++);
2040 pktlen = msg_size(hdr);
2042 /* Tunnel link MTU is not large enough? This could be
2044 * 1) Link MTU has just changed or set differently;
2045 * 2) Or FAILOVER on the top of a SYNCH message
2047 * The 2nd case should not happen if peer supports
2048 * TIPC_TUNNEL_ENHANCED
2050 if (pktlen > tnl->mtu - INT_H_SIZE) {
2051 if (mtyp == FAILOVER_MSG &&
2052 (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
2053 rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
2056 pr_warn("%sunable to frag msg: rc %d\n",
2060 pktcnt += skb_queue_len(&frags) - 1;
2061 pktcnt_need_update = true;
2062 skb_queue_splice_tail_init(&frags, &tnlq);
2065 /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
2066 * => Just warn it and return!
2068 pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
2069 link_co_err, msg_user(hdr),
2070 msg_type(hdr), msg_size(hdr));
2074 msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
2075 tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
2077 pr_warn("%sunable to send packet\n", link_co_err);
2080 skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
2081 skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
2082 __skb_queue_tail(&tnlq, tnlskb);
2084 if (queue != &l->backlogq) {
2085 queue = &l->backlogq;
2089 if (pktcnt_need_update)
2090 skb_queue_walk(&tnlq, skb) {
2092 msg_set_msgcnt(hdr, pktcnt);
2095 tipc_link_xmit(tnl, &tnlq, xmitq);
2097 if (mtyp == FAILOVER_MSG) {
2098 tnl->drop_point = l->rcv_nxt;
2099 tnl->failover_reasm_skb = l->reasm_buf;
2100 l->reasm_buf = NULL;
2102 /* Failover the link's deferdq */
2103 if (unlikely(!skb_queue_empty(fdefq))) {
2104 pr_warn("Link failover deferdq not empty: %d!\n",
2105 skb_queue_len(fdefq));
2106 __skb_queue_purge(fdefq);
2108 skb_queue_splice_init(&l->deferdq, fdefq);
2113 * tipc_link_failover_prepare() - prepare tnl for link failover
2115 * This is a special version of the precursor - tipc_link_tnl_prepare(),
2116 * see the tipc_node_link_failover() for details
2120 * @xmitq: queue for messages to be xmited
2122 void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
2123 struct sk_buff_head *xmitq)
2125 struct sk_buff_head *fdefq = &tnl->failover_deferdq;
2127 tipc_link_create_dummy_tnl_msg(tnl, xmitq);
2129 /* This failover link endpoint was never established before,
2130 * so it has not received anything from peer.
2131 * Otherwise, it must be a normal failover situation or the
2132 * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
2133 * would have to start over from scratch instead.
2135 tnl->drop_point = 1;
2136 tnl->failover_reasm_skb = NULL;
2138 /* Initiate the link's failover deferdq */
2139 if (unlikely(!skb_queue_empty(fdefq))) {
2140 pr_warn("Link failover deferdq not empty: %d!\n",
2141 skb_queue_len(fdefq));
2142 __skb_queue_purge(fdefq);
2146 /* tipc_link_validate_msg(): validate message against current link state
2147 * Returns true if message should be accepted, otherwise false
2149 bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
2151 u16 curr_session = l->peer_session;
2152 u16 session = msg_session(hdr);
2153 int mtyp = msg_type(hdr);
2155 if (msg_user(hdr) != LINK_PROTOCOL)
2162 /* Accept only RESET with new session number */
2163 return more(session, curr_session);
2167 /* Accept only ACTIVATE with new or current session number */
2168 return !less(session, curr_session);
2170 /* Accept only STATE with current session number */
2173 if (session != curr_session)
2175 /* Extra sanity check */
2176 if (!link_is_up(l) && msg_ack(hdr))
2178 if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
2180 /* Accept only STATE with new sequence number */
2181 return !less(msg_seqno(hdr), l->rcv_nxt_state);
2187 /* tipc_link_proto_rcv(): receive link level protocol message :
2188 * Note that network plane id propagates through the network, and may
2189 * change at any time. The node with lowest numerical id determines
2192 static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
2193 struct sk_buff_head *xmitq)
2195 struct tipc_msg *hdr = buf_msg(skb);
2196 struct tipc_gap_ack_blks *ga = NULL;
2197 bool reply = msg_probe(hdr), retransmitted = false;
2198 u16 dlen = msg_data_sz(hdr), glen = 0;
2199 u16 peers_snd_nxt = msg_next_sent(hdr);
2200 u16 peers_tol = msg_link_tolerance(hdr);
2201 u16 peers_prio = msg_linkprio(hdr);
2202 u16 gap = msg_seq_gap(hdr);
2203 u16 ack = msg_ack(hdr);
2204 u16 rcv_nxt = l->rcv_nxt;
2206 int mtyp = msg_type(hdr);
2207 int rc = 0, released;
2211 trace_tipc_proto_rcv(skb, false, l->name);
2212 if (tipc_link_is_blocked(l) || !xmitq)
2215 if (tipc_own_addr(l->net) > msg_prevnode(hdr))
2216 l->net_plane = msg_net_plane(hdr);
2220 data = msg_data(hdr);
2222 if (!tipc_link_validate_msg(l, hdr)) {
2223 trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
2224 trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
2231 /* Complete own link name with peer's interface name */
2232 if_name = strrchr(l->name, ':') + 1;
2233 if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
2235 if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
2237 strncpy(if_name, data, TIPC_MAX_IF_NAME);
2239 /* Update own tolerance if peer indicates a non-zero value */
2240 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2241 l->tolerance = peers_tol;
2242 l->bc_rcvlink->tolerance = peers_tol;
2244 /* Update own priority if peer's priority is higher */
2245 if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
2246 l->priority = peers_prio;
2248 /* If peer is going down we want full re-establish cycle */
2249 if (msg_peer_stopping(hdr)) {
2250 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2254 /* If this endpoint was re-created while peer was ESTABLISHING
2255 * it doesn't know current session number. Force re-synch.
2257 if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
2258 l->session != msg_dest_session(hdr)) {
2259 if (less(l->session, msg_dest_session(hdr)))
2260 l->session = msg_dest_session(hdr) + 1;
2264 /* ACTIVATE_MSG serves as PEER_RESET if link is already down */
2265 if (mtyp == RESET_MSG || !link_is_up(l))
2266 rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT);
2268 /* ACTIVATE_MSG takes up link if it was already locally reset */
2269 if (mtyp == ACTIVATE_MSG && l->state == LINK_ESTABLISHING)
2270 rc = TIPC_LINK_UP_EVT;
2272 l->peer_session = msg_session(hdr);
2273 l->in_session = true;
2274 l->peer_bearer_id = msg_bearer_id(hdr);
2275 if (l->mtu > msg_max_pkt(hdr))
2276 l->mtu = msg_max_pkt(hdr);
2280 l->rcv_nxt_state = msg_seqno(hdr) + 1;
2282 /* Update own tolerance if peer indicates a non-zero value */
2283 if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
2284 l->tolerance = peers_tol;
2285 l->bc_rcvlink->tolerance = peers_tol;
2287 /* Update own prio if peer indicates a different value */
2288 if ((peers_prio != l->priority) &&
2289 in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
2290 l->priority = peers_prio;
2291 rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
2294 l->silent_intv_cnt = 0;
2295 l->stats.recv_states++;
2297 l->stats.recv_probes++;
2299 if (!link_is_up(l)) {
2300 if (l->state == LINK_ESTABLISHING)
2301 rc = TIPC_LINK_UP_EVT;
2305 /* Receive Gap ACK blocks from peer if any */
2306 glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
2308 tipc_mon_rcv(l->net, data + glen, dlen - glen, l->addr,
2309 &l->mon_state, l->bearer_id);
2311 /* Send NACK if peer has sent pkts we haven't received yet */
2312 if ((reply || msg_is_keepalive(hdr)) &&
2313 more(peers_snd_nxt, rcv_nxt) &&
2314 !tipc_link_is_synching(l) &&
2315 skb_queue_empty(&l->deferdq))
2316 rcvgap = peers_snd_nxt - l->rcv_nxt;
2317 if (rcvgap || reply)
2318 tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
2319 rcvgap, 0, 0, xmitq);
2321 released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
2322 &retransmitted, &rc);
2324 l->stats.recv_nacks++;
2325 if (released || retransmitted)
2326 tipc_link_update_cwin(l, released, retransmitted);
2328 tipc_link_advance_backlog(l, xmitq);
2329 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2330 link_prepare_wakeup(l);
2337 /* tipc_link_build_bc_proto_msg() - create broadcast protocol message
2339 static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
2341 struct sk_buff_head *xmitq)
2343 struct sk_buff *skb;
2344 struct tipc_msg *hdr;
2345 struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
2346 u16 ack = l->rcv_nxt - 1;
2347 u16 gap_to = peers_snd_nxt - 1;
2349 skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
2350 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
2354 msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
2355 msg_set_bcast_ack(hdr, ack);
2356 msg_set_bcgap_after(hdr, ack);
2358 gap_to = buf_seqno(dfrd_skb) - 1;
2359 msg_set_bcgap_to(hdr, gap_to);
2360 msg_set_non_seq(hdr, bcast);
2361 __skb_queue_tail(xmitq, skb);
2365 /* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
2367 * Give a newly added peer node the sequence number where it should
2368 * start receiving and acking broadcast packets.
2370 static void tipc_link_build_bc_init_msg(struct tipc_link *l,
2371 struct sk_buff_head *xmitq)
2373 struct sk_buff_head list;
2375 __skb_queue_head_init(&list);
2376 if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
2378 msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
2379 tipc_link_xmit(l, &list, xmitq);
2382 /* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
2384 void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
2386 int mtyp = msg_type(hdr);
2387 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2392 if (msg_user(hdr) == BCAST_PROTOCOL) {
2393 l->rcv_nxt = peers_snd_nxt;
2394 l->state = LINK_ESTABLISHED;
2398 if (l->peer_caps & TIPC_BCAST_SYNCH)
2401 if (msg_peer_node_is_up(hdr))
2404 /* Compatibility: accept older, less safe initial synch data */
2405 if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
2406 l->rcv_nxt = peers_snd_nxt;
2409 /* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
2411 int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
2412 struct sk_buff_head *xmitq)
2414 u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
2420 if (!msg_peer_node_is_up(hdr))
2423 /* Open when peer acknowledges our bcast init msg (pkt #1) */
2425 l->bc_peer_is_up = true;
2427 if (!l->bc_peer_is_up)
2430 /* Ignore if peers_snd_nxt goes beyond receive window */
2431 if (more(peers_snd_nxt, l->rcv_nxt + l->window))
2434 l->snd_nxt = peers_snd_nxt;
2435 if (link_bc_rcv_gap(l))
2436 rc |= TIPC_LINK_SND_STATE;
2438 /* Return now if sender supports nack via STATE messages */
2439 if (l->peer_caps & TIPC_BCAST_STATE_NACK)
2442 /* Otherwise, be backwards compatible */
2444 if (!more(peers_snd_nxt, l->rcv_nxt)) {
2445 l->nack_state = BC_NACK_SND_CONDITIONAL;
2449 /* Don't NACK if one was recently sent or peeked */
2450 if (l->nack_state == BC_NACK_SND_SUPPRESS) {
2451 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2455 /* Conditionally delay NACK sending until next synch rcv */
2456 if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
2457 l->nack_state = BC_NACK_SND_UNCONDITIONAL;
2458 if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
2462 /* Send NACK now but suppress next one */
2463 tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
2464 l->nack_state = BC_NACK_SND_SUPPRESS;
2468 int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
2469 struct tipc_gap_ack_blks *ga,
2470 struct sk_buff_head *xmitq,
2471 struct sk_buff_head *retrq)
2473 struct tipc_link *l = r->bc_sndlink;
2474 bool unused = false;
2477 if (!link_is_up(r) || !r->bc_peer_is_up)
2481 l->stats.recv_nacks++;
2482 r->stats.recv_nacks++;
2485 if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
2488 trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
2489 tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
2491 tipc_link_advance_backlog(l, xmitq);
2492 if (unlikely(!skb_queue_empty(&l->wakeupq)))
2493 link_prepare_wakeup(l);
2498 /* tipc_link_bc_nack_rcv(): receive broadcast nack message
2499 * This function is here for backwards compatibility, since
2500 * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
2502 int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
2503 struct sk_buff_head *xmitq)
2505 struct tipc_msg *hdr = buf_msg(skb);
2506 u32 dnode = msg_destnode(hdr);
2507 int mtyp = msg_type(hdr);
2508 u16 acked = msg_bcast_ack(hdr);
2509 u16 from = acked + 1;
2510 u16 to = msg_bcgap_to(hdr);
2511 u16 peers_snd_nxt = to + 1;
2516 if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
2519 if (mtyp != STATE_MSG)
2522 if (dnode == tipc_own_addr(l->net)) {
2523 rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
2525 l->stats.recv_nacks++;
2529 /* Msg for other node => suppress own NACK at next sync if applicable */
2530 if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
2531 l->nack_state = BC_NACK_SND_SUPPRESS;
2536 void tipc_link_set_queue_limits(struct tipc_link *l, u32 min_win, u32 max_win)
2538 int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
2540 l->min_win = min_win;
2541 l->ssthresh = max_win;
2542 l->max_win = max_win;
2543 l->window = min_win;
2544 l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
2545 l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
2546 l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
2547 l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
2548 l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
2552 * tipc_link_reset_stats - reset link statistics
2553 * @l: pointer to link
2555 void tipc_link_reset_stats(struct tipc_link *l)
2557 memset(&l->stats, 0, sizeof(l->stats));
2560 static void link_print(struct tipc_link *l, const char *str)
2562 struct sk_buff *hskb = skb_peek(&l->transmq);
2563 u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
2564 u16 tail = l->snd_nxt - 1;
2566 pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
2567 pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
2568 skb_queue_len(&l->transmq), head, tail,
2569 skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
2572 /* Parse and validate nested (link) properties valid for media, bearer and link
2574 int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
2578 err = nla_parse_nested_deprecated(props, TIPC_NLA_PROP_MAX, prop,
2579 tipc_nl_prop_policy, NULL);
2583 if (props[TIPC_NLA_PROP_PRIO]) {
2586 prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
2587 if (prio > TIPC_MAX_LINK_PRI)
2591 if (props[TIPC_NLA_PROP_TOL]) {
2594 tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
2595 if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
2599 if (props[TIPC_NLA_PROP_WIN]) {
2602 max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
2603 if (max_win < TIPC_DEF_LINK_WIN || max_win > TIPC_MAX_LINK_WIN)
2610 static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
2613 struct nlattr *stats;
2620 struct nla_map map[] = {
2621 {TIPC_NLA_STATS_RX_INFO, 0},
2622 {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
2623 {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
2624 {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
2625 {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
2626 {TIPC_NLA_STATS_TX_INFO, 0},
2627 {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
2628 {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
2629 {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
2630 {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
2631 {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
2632 s->msg_length_counts : 1},
2633 {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
2634 {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
2635 {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
2636 {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
2637 {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
2638 {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
2639 {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
2640 {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
2641 {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
2642 {TIPC_NLA_STATS_RX_STATES, s->recv_states},
2643 {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
2644 {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
2645 {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
2646 {TIPC_NLA_STATS_TX_STATES, s->sent_states},
2647 {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
2648 {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
2649 {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
2650 {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
2651 {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
2652 {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
2653 {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
2654 {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
2655 (s->accu_queue_sz / s->queue_sz_counts) : 0}
2658 stats = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2662 for (i = 0; i < ARRAY_SIZE(map); i++)
2663 if (nla_put_u32(skb, map[i].key, map[i].val))
2666 nla_nest_end(skb, stats);
2670 nla_nest_cancel(skb, stats);
2675 /* Caller should hold appropriate locks to protect the link */
2676 int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
2677 struct tipc_link *link, int nlflags)
2679 u32 self = tipc_own_addr(net);
2680 struct nlattr *attrs;
2681 struct nlattr *prop;
2685 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2686 nlflags, TIPC_NL_LINK_GET);
2690 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2694 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
2696 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
2698 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
2700 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
2702 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
2705 if (tipc_link_is_up(link))
2706 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2709 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
2712 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2715 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2717 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
2719 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
2722 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
2724 nla_nest_end(msg->skb, prop);
2726 err = __tipc_nl_add_stats(msg->skb, &link->stats);
2730 nla_nest_end(msg->skb, attrs);
2731 genlmsg_end(msg->skb, hdr);
2736 nla_nest_cancel(msg->skb, prop);
2738 nla_nest_cancel(msg->skb, attrs);
2740 genlmsg_cancel(msg->skb, hdr);
2745 static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
2746 struct tipc_stats *stats)
2749 struct nlattr *nest;
2756 struct nla_map map[] = {
2757 {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
2758 {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
2759 {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
2760 {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
2761 {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
2762 {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
2763 {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
2764 {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
2765 {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
2766 {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
2767 {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
2768 {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
2769 {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
2770 {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
2771 {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
2772 {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
2773 {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
2774 {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
2775 {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
2776 (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
2779 nest = nla_nest_start_noflag(skb, TIPC_NLA_LINK_STATS);
2783 for (i = 0; i < ARRAY_SIZE(map); i++)
2784 if (nla_put_u32(skb, map[i].key, map[i].val))
2787 nla_nest_end(skb, nest);
2791 nla_nest_cancel(skb, nest);
2796 int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg,
2797 struct tipc_link *bcl)
2801 struct nlattr *attrs;
2802 struct nlattr *prop;
2803 u32 bc_mode = tipc_bcast_get_mode(net);
2804 u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
2809 tipc_bcast_lock(net);
2811 hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
2812 NLM_F_MULTI, TIPC_NL_LINK_GET);
2814 tipc_bcast_unlock(net);
2818 attrs = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK);
2822 /* The broadcast link is always up */
2823 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
2826 if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
2828 if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
2830 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
2832 if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
2835 prop = nla_nest_start_noflag(msg->skb, TIPC_NLA_LINK_PROP);
2838 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
2840 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
2842 if (bc_mode & BCLINK_MODE_SEL)
2843 if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
2846 nla_nest_end(msg->skb, prop);
2848 err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
2852 tipc_bcast_unlock(net);
2853 nla_nest_end(msg->skb, attrs);
2854 genlmsg_end(msg->skb, hdr);
2859 nla_nest_cancel(msg->skb, prop);
2861 nla_nest_cancel(msg->skb, attrs);
2863 tipc_bcast_unlock(net);
2864 genlmsg_cancel(msg->skb, hdr);
2869 void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
2870 struct sk_buff_head *xmitq)
2874 l->bc_rcvlink->tolerance = tol;
2876 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
2879 void tipc_link_set_prio(struct tipc_link *l, u32 prio,
2880 struct sk_buff_head *xmitq)
2883 tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
2886 void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
2888 l->abort_limit = limit;
2892 * tipc_link_dump - dump TIPC link data
2893 * @l: tipc link to be dumped
2894 * @dqueues: bitmask to decide if any link queue to be dumped?
2895 * - TIPC_DUMP_NONE: don't dump link queues
2896 * - TIPC_DUMP_TRANSMQ: dump link transmq queue
2897 * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
2898 * - TIPC_DUMP_DEFERDQ: dump link deferd queue
2899 * - TIPC_DUMP_INPUTQ: dump link input queue
2900 * - TIPC_DUMP_WAKEUP: dump link wakeup queue
2901 * - TIPC_DUMP_ALL: dump all the link queues above
2902 * @buf: returned buffer of dump data in format
2904 int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
2907 size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
2908 struct sk_buff_head *list;
2909 struct sk_buff *hskb, *tskb;
2913 i += scnprintf(buf, sz, "link data: (null)\n");
2917 i += scnprintf(buf, sz, "link data: %x", l->addr);
2918 i += scnprintf(buf + i, sz - i, " %x", l->state);
2919 i += scnprintf(buf + i, sz - i, " %u", l->in_session);
2920 i += scnprintf(buf + i, sz - i, " %u", l->session);
2921 i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
2922 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
2923 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
2924 i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
2925 i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
2926 i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
2927 i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
2928 i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
2929 i += scnprintf(buf + i, sz - i, " %u", 0);
2930 i += scnprintf(buf + i, sz - i, " %u", 0);
2931 i += scnprintf(buf + i, sz - i, " %u", l->acked);
2934 len = skb_queue_len(list);
2935 hskb = skb_peek(list);
2936 tskb = skb_peek_tail(list);
2937 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2938 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2939 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2942 len = skb_queue_len(list);
2943 hskb = skb_peek(list);
2944 tskb = skb_peek_tail(list);
2945 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2946 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2947 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2949 list = &l->backlogq;
2950 len = skb_queue_len(list);
2951 hskb = skb_peek(list);
2952 tskb = skb_peek_tail(list);
2953 i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
2954 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2955 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2958 len = skb_queue_len(list);
2959 hskb = skb_peek(list);
2960 tskb = skb_peek_tail(list);
2961 i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
2962 (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
2963 (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
2965 if (dqueues & TIPC_DUMP_TRANSMQ) {
2966 i += scnprintf(buf + i, sz - i, "transmq: ");
2967 i += tipc_list_dump(&l->transmq, false, buf + i);
2969 if (dqueues & TIPC_DUMP_BACKLOGQ) {
2970 i += scnprintf(buf + i, sz - i,
2971 "backlogq: <%u %u %u %u %u>, ",
2972 l->backlog[TIPC_LOW_IMPORTANCE].len,
2973 l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
2974 l->backlog[TIPC_HIGH_IMPORTANCE].len,
2975 l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
2976 l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
2977 i += tipc_list_dump(&l->backlogq, false, buf + i);
2979 if (dqueues & TIPC_DUMP_DEFERDQ) {
2980 i += scnprintf(buf + i, sz - i, "deferdq: ");
2981 i += tipc_list_dump(&l->deferdq, false, buf + i);
2983 if (dqueues & TIPC_DUMP_INPUTQ) {
2984 i += scnprintf(buf + i, sz - i, "inputq: ");
2985 i += tipc_list_dump(l->inputq, false, buf + i);
2987 if (dqueues & TIPC_DUMP_WAKEUP) {
2988 i += scnprintf(buf + i, sz - i, "wakeup: ");
2989 i += tipc_list_dump(&l->wakeupq, false, buf + i);