2 * net/tipc/bcast.c: TIPC broadcast code
4 * Copyright (c) 2004-2006, 2014-2017, Ericsson AB
5 * Copyright (c) 2004, Intel Corporation.
6 * Copyright (c) 2005, 2010-2011, Wind River Systems
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the names of the copyright holders nor the names of its
18 * contributors may be used to endorse or promote products derived from
19 * this software without specific prior written permission.
21 * Alternatively, this software may be distributed under the terms of the
22 * GNU General Public License ("GPL") version 2 as published by the Free
23 * Software Foundation.
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
26 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
29 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
38 #include <linux/tipc_config.h>
43 #include "name_table.h"
45 #define BCLINK_WIN_DEFAULT 50 /* bcast link window size (default) */
46 #define BCLINK_WIN_MIN 32 /* bcast minimum link window size */
48 const char tipc_bclink_name[] = "broadcast-link";
49 unsigned long sysctl_tipc_bc_retruni __read_mostly;
52 * struct tipc_bc_base - base structure for keeping broadcast send state
53 * @link: broadcast send link structure
54 * @inputq: data input queue; will only carry SOCK_WAKEUP messages
55 * @dests: array keeping number of reachable destinations per bearer
56 * @primary_bearer: a bearer having links to all broadcast destinations, if any
57 * @bcast_support: indicates if primary bearer, if any, supports broadcast
58 * @force_bcast: forces broadcast for multicast traffic
59 * @rcast_support: indicates if all peer nodes support replicast
60 * @force_rcast: forces replicast for multicast traffic
61 * @rc_ratio: dest count as percentage of cluster size where send method changes
62 * @bc_threshold: calculated from rc_ratio; if dests > threshold use broadcast
65 struct tipc_link *link;
66 struct sk_buff_head inputq;
67 int dests[MAX_BEARERS];
77 static struct tipc_bc_base *tipc_bc_base(struct net *net)
79 return tipc_net(net)->bcbase;
82 /* tipc_bcast_get_mtu(): -get the MTU currently used by broadcast link
83 * Note: the MTU is decremented to give room for a tunnel header, in
84 * case the message needs to be sent as replicast
86 int tipc_bcast_get_mtu(struct net *net)
88 return tipc_link_mss(tipc_bc_sndlink(net));
91 void tipc_bcast_toggle_rcast(struct net *net, bool supp)
93 tipc_bc_base(net)->rcast_support = supp;
96 static void tipc_bcbase_calc_bc_threshold(struct net *net)
98 struct tipc_bc_base *bb = tipc_bc_base(net);
99 int cluster_size = tipc_link_bc_peers(tipc_bc_sndlink(net));
101 bb->bc_threshold = 1 + (cluster_size * bb->rc_ratio / 100);
104 /* tipc_bcbase_select_primary(): find a bearer with links to all destinations,
105 * if any, and make it primary bearer
107 static void tipc_bcbase_select_primary(struct net *net)
109 struct tipc_bc_base *bb = tipc_bc_base(net);
110 int all_dests = tipc_link_bc_peers(bb->link);
111 int max_win = tipc_link_max_win(bb->link);
112 int min_win = tipc_link_min_win(bb->link);
115 bb->primary_bearer = INVALID_BEARER_ID;
116 bb->bcast_support = true;
121 for (i = 0; i < MAX_BEARERS; i++) {
125 mtu = tipc_bearer_mtu(net, i);
126 if (mtu < tipc_link_mtu(bb->link)) {
127 tipc_link_set_mtu(bb->link, mtu);
128 tipc_link_set_queue_limits(bb->link,
132 bb->bcast_support &= tipc_bearer_bcast_support(net, i);
133 if (bb->dests[i] < all_dests)
136 bb->primary_bearer = i;
138 /* Reduce risk that all nodes select same primary */
139 if ((i ^ tipc_own_addr(net)) & 1)
142 prim = bb->primary_bearer;
143 if (prim != INVALID_BEARER_ID)
144 bb->bcast_support = tipc_bearer_bcast_support(net, prim);
147 void tipc_bcast_inc_bearer_dst_cnt(struct net *net, int bearer_id)
149 struct tipc_bc_base *bb = tipc_bc_base(net);
151 tipc_bcast_lock(net);
152 bb->dests[bearer_id]++;
153 tipc_bcbase_select_primary(net);
154 tipc_bcast_unlock(net);
157 void tipc_bcast_dec_bearer_dst_cnt(struct net *net, int bearer_id)
159 struct tipc_bc_base *bb = tipc_bc_base(net);
161 tipc_bcast_lock(net);
162 bb->dests[bearer_id]--;
163 tipc_bcbase_select_primary(net);
164 tipc_bcast_unlock(net);
167 /* tipc_bcbase_xmit - broadcast a packet queue across one or more bearers
169 * Note that number of reachable destinations, as indicated in the dests[]
170 * array, may transitionally differ from the number of destinations indicated
171 * in each sent buffer. We can sustain this. Excess destination nodes will
172 * drop and never acknowledge the unexpected packets, and missing destinations
173 * will either require retransmission (if they are just about to be added to
174 * the bearer), or be removed from the buffer's 'ackers' counter (if they
177 static void tipc_bcbase_xmit(struct net *net, struct sk_buff_head *xmitq)
180 struct tipc_bc_base *bb = tipc_bc_base(net);
181 struct sk_buff *skb, *_skb;
182 struct sk_buff_head _xmitq;
184 if (skb_queue_empty(xmitq))
187 /* The typical case: at least one bearer has links to all nodes */
188 bearer_id = bb->primary_bearer;
189 if (bearer_id >= 0) {
190 tipc_bearer_bc_xmit(net, bearer_id, xmitq);
194 /* We have to transmit across all bearers */
195 __skb_queue_head_init(&_xmitq);
196 for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) {
197 if (!bb->dests[bearer_id])
200 skb_queue_walk(xmitq, skb) {
201 _skb = pskb_copy_for_clone(skb, GFP_ATOMIC);
204 __skb_queue_tail(&_xmitq, _skb);
206 tipc_bearer_bc_xmit(net, bearer_id, &_xmitq);
208 __skb_queue_purge(xmitq);
209 __skb_queue_purge(&_xmitq);
212 static void tipc_bcast_select_xmit_method(struct net *net, int dests,
213 struct tipc_mc_method *method)
215 struct tipc_bc_base *bb = tipc_bc_base(net);
216 unsigned long exp = method->expires;
218 /* Broadcast supported by used bearer/bearers? */
219 if (!bb->bcast_support) {
220 method->rcast = true;
223 /* Any destinations which don't support replicast ? */
224 if (!bb->rcast_support) {
225 method->rcast = false;
228 /* Can current method be changed ? */
229 method->expires = jiffies + TIPC_METHOD_EXPIRE;
230 if (method->mandatory)
233 if (!(tipc_net(net)->capabilities & TIPC_MCAST_RBCTL) &&
234 time_before(jiffies, exp))
237 /* Configuration as force 'broadcast' method */
238 if (bb->force_bcast) {
239 method->rcast = false;
242 /* Configuration as force 'replicast' method */
243 if (bb->force_rcast) {
244 method->rcast = true;
247 /* Configuration as 'autoselect' or default method */
248 /* Determine method to use now */
249 method->rcast = dests <= bb->bc_threshold;
252 /* tipc_bcast_xmit - broadcast the buffer chain to all external nodes
253 * @net: the applicable net namespace
254 * @pkts: chain of buffers containing message
255 * @cong_link_cnt: set to 1 if broadcast link is congested, otherwise 0
256 * Consumes the buffer chain.
257 * Returns 0 if success, otherwise errno: -EHOSTUNREACH,-EMSGSIZE
259 int tipc_bcast_xmit(struct net *net, struct sk_buff_head *pkts,
262 struct tipc_link *l = tipc_bc_sndlink(net);
263 struct sk_buff_head xmitq;
266 __skb_queue_head_init(&xmitq);
267 tipc_bcast_lock(net);
268 if (tipc_link_bc_peers(l))
269 rc = tipc_link_xmit(l, pkts, &xmitq);
270 tipc_bcast_unlock(net);
271 tipc_bcbase_xmit(net, &xmitq);
272 __skb_queue_purge(pkts);
273 if (rc == -ELINKCONG) {
280 /* tipc_rcast_xmit - replicate and send a message to given destination nodes
281 * @net: the applicable net namespace
282 * @pkts: chain of buffers containing message
283 * @dests: list of destination nodes
284 * @cong_link_cnt: returns number of congested links
285 * @cong_links: returns identities of congested links
286 * Returns 0 if success, otherwise errno
288 static int tipc_rcast_xmit(struct net *net, struct sk_buff_head *pkts,
289 struct tipc_nlist *dests, u16 *cong_link_cnt)
291 struct tipc_dest *dst, *tmp;
292 struct sk_buff_head _pkts;
295 selector = msg_link_selector(buf_msg(skb_peek(pkts)));
296 __skb_queue_head_init(&_pkts);
298 list_for_each_entry_safe(dst, tmp, &dests->list, list) {
300 if (!tipc_msg_pskb_copy(dnode, pkts, &_pkts))
303 /* Any other return value than -ELINKCONG is ignored */
304 if (tipc_node_xmit(net, &_pkts, dnode, selector) == -ELINKCONG)
310 /* tipc_mcast_send_sync - deliver a dummy message with SYN bit
311 * @net: the applicable net namespace
312 * @skb: socket buffer to copy
313 * @method: send method to be used
314 * @dests: destination nodes for message.
315 * Returns 0 if success, otherwise errno
317 static int tipc_mcast_send_sync(struct net *net, struct sk_buff *skb,
318 struct tipc_mc_method *method,
319 struct tipc_nlist *dests)
321 struct tipc_msg *hdr, *_hdr;
322 struct sk_buff_head tmpq;
323 struct sk_buff *_skb;
327 /* Is a cluster supporting with new capabilities ? */
328 if (!(tipc_net(net)->capabilities & TIPC_MCAST_RBCTL))
332 if (msg_user(hdr) == MSG_FRAGMENTER)
333 hdr = msg_inner_hdr(hdr);
334 if (msg_type(hdr) != TIPC_MCAST_MSG)
337 /* Allocate dummy message */
338 _skb = tipc_buf_acquire(MCAST_H_SIZE, GFP_KERNEL);
342 /* Preparing for 'synching' header */
345 /* Copy skb's header into a dummy header */
346 skb_copy_to_linear_data(_skb, hdr, MCAST_H_SIZE);
349 /* Reverse method for dummy message */
350 _hdr = buf_msg(_skb);
351 msg_set_size(_hdr, MCAST_H_SIZE);
352 msg_set_is_rcast(_hdr, !msg_is_rcast(hdr));
353 msg_set_errcode(_hdr, TIPC_ERR_NO_PORT);
355 __skb_queue_head_init(&tmpq);
356 __skb_queue_tail(&tmpq, _skb);
358 rc = tipc_bcast_xmit(net, &tmpq, &cong_link_cnt);
360 rc = tipc_rcast_xmit(net, &tmpq, dests, &cong_link_cnt);
362 /* This queue should normally be empty by now */
363 __skb_queue_purge(&tmpq);
368 /* tipc_mcast_xmit - deliver message to indicated destination nodes
369 * and to identified node local sockets
370 * @net: the applicable net namespace
371 * @pkts: chain of buffers containing message
372 * @method: send method to be used
373 * @dests: destination nodes for message.
374 * @cong_link_cnt: returns number of encountered congested destination links
375 * Consumes buffer chain.
376 * Returns 0 if success, otherwise errno
378 int tipc_mcast_xmit(struct net *net, struct sk_buff_head *pkts,
379 struct tipc_mc_method *method, struct tipc_nlist *dests,
382 struct sk_buff_head inputq, localq;
383 bool rcast = method->rcast;
384 struct tipc_msg *hdr;
388 skb_queue_head_init(&inputq);
389 __skb_queue_head_init(&localq);
391 /* Clone packets before they are consumed by next call */
392 if (dests->local && !tipc_msg_reassemble(pkts, &localq)) {
396 /* Send according to determined transmit method */
398 tipc_bcast_select_xmit_method(net, dests->remote, method);
400 skb = skb_peek(pkts);
402 if (msg_user(hdr) == MSG_FRAGMENTER)
403 hdr = msg_inner_hdr(hdr);
404 msg_set_is_rcast(hdr, method->rcast);
406 /* Switch method ? */
407 if (rcast != method->rcast) {
408 rc = tipc_mcast_send_sync(net, skb, method, dests);
410 pr_err("Unable to send SYN: method %d, rc %d\n",
417 rc = tipc_rcast_xmit(net, pkts, dests, cong_link_cnt);
419 rc = tipc_bcast_xmit(net, pkts, cong_link_cnt);
423 tipc_loopback_trace(net, &localq);
424 tipc_sk_mcast_rcv(net, &localq, &inputq);
427 /* This queue should normally be empty by now */
428 __skb_queue_purge(pkts);
432 /* tipc_bcast_rcv - receive a broadcast packet, and deliver to rcv link
434 * RCU is locked, no other locks set
436 int tipc_bcast_rcv(struct net *net, struct tipc_link *l, struct sk_buff *skb)
438 struct tipc_msg *hdr = buf_msg(skb);
439 struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
440 struct sk_buff_head xmitq;
443 __skb_queue_head_init(&xmitq);
445 if (msg_mc_netid(hdr) != tipc_netid(net) || !tipc_link_is_up(l)) {
450 tipc_bcast_lock(net);
451 if (msg_user(hdr) == BCAST_PROTOCOL)
452 rc = tipc_link_bc_nack_rcv(l, skb, &xmitq);
454 rc = tipc_link_rcv(l, skb, NULL);
455 tipc_bcast_unlock(net);
457 tipc_bcbase_xmit(net, &xmitq);
459 /* Any socket wakeup messages ? */
460 if (!skb_queue_empty(inputq))
461 tipc_sk_rcv(net, inputq);
466 /* tipc_bcast_ack_rcv - receive and handle a broadcast acknowledge
468 * RCU is locked, no other locks set
470 void tipc_bcast_ack_rcv(struct net *net, struct tipc_link *l,
471 struct tipc_msg *hdr)
473 struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
474 u16 acked = msg_bcast_ack(hdr);
475 struct sk_buff_head xmitq;
477 /* Ignore bc acks sent by peer before bcast synch point was received */
478 if (msg_bc_ack_invalid(hdr))
481 __skb_queue_head_init(&xmitq);
483 tipc_bcast_lock(net);
484 tipc_link_bc_ack_rcv(l, acked, 0, NULL, &xmitq, NULL);
485 tipc_bcast_unlock(net);
487 tipc_bcbase_xmit(net, &xmitq);
489 /* Any socket wakeup messages ? */
490 if (!skb_queue_empty(inputq))
491 tipc_sk_rcv(net, inputq);
494 /* tipc_bcast_synch_rcv - check and update rcv link with peer's send state
496 * RCU is locked, no other locks set
498 int tipc_bcast_sync_rcv(struct net *net, struct tipc_link *l,
499 struct tipc_msg *hdr,
500 struct sk_buff_head *retrq)
502 struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
503 struct tipc_gap_ack_blks *ga;
504 struct sk_buff_head xmitq;
507 __skb_queue_head_init(&xmitq);
509 tipc_bcast_lock(net);
510 if (msg_type(hdr) != STATE_MSG) {
511 tipc_link_bc_init_rcv(l, hdr);
512 } else if (!msg_bc_ack_invalid(hdr)) {
513 tipc_get_gap_ack_blks(&ga, l, hdr, false);
514 if (!sysctl_tipc_bc_retruni)
516 rc = tipc_link_bc_ack_rcv(l, msg_bcast_ack(hdr),
517 msg_bc_gap(hdr), ga, &xmitq,
519 rc |= tipc_link_bc_sync_rcv(l, hdr, &xmitq);
521 tipc_bcast_unlock(net);
523 tipc_bcbase_xmit(net, &xmitq);
525 /* Any socket wakeup messages ? */
526 if (!skb_queue_empty(inputq))
527 tipc_sk_rcv(net, inputq);
531 /* tipc_bcast_add_peer - add a peer node to broadcast link and bearer
533 * RCU is locked, node lock is set
535 void tipc_bcast_add_peer(struct net *net, struct tipc_link *uc_l,
536 struct sk_buff_head *xmitq)
538 struct tipc_link *snd_l = tipc_bc_sndlink(net);
540 tipc_bcast_lock(net);
541 tipc_link_add_bc_peer(snd_l, uc_l, xmitq);
542 tipc_bcbase_select_primary(net);
543 tipc_bcbase_calc_bc_threshold(net);
544 tipc_bcast_unlock(net);
547 /* tipc_bcast_remove_peer - remove a peer node from broadcast link and bearer
549 * RCU is locked, node lock is set
551 void tipc_bcast_remove_peer(struct net *net, struct tipc_link *rcv_l)
553 struct tipc_link *snd_l = tipc_bc_sndlink(net);
554 struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq;
555 struct sk_buff_head xmitq;
557 __skb_queue_head_init(&xmitq);
559 tipc_bcast_lock(net);
560 tipc_link_remove_bc_peer(snd_l, rcv_l, &xmitq);
561 tipc_bcbase_select_primary(net);
562 tipc_bcbase_calc_bc_threshold(net);
563 tipc_bcast_unlock(net);
565 tipc_bcbase_xmit(net, &xmitq);
567 /* Any socket wakeup messages ? */
568 if (!skb_queue_empty(inputq))
569 tipc_sk_rcv(net, inputq);
572 int tipc_bclink_reset_stats(struct net *net, struct tipc_link *l)
577 tipc_bcast_lock(net);
578 tipc_link_reset_stats(l);
579 tipc_bcast_unlock(net);
583 static int tipc_bc_link_set_queue_limits(struct net *net, u32 max_win)
585 struct tipc_link *l = tipc_bc_sndlink(net);
589 if (max_win < BCLINK_WIN_MIN)
590 max_win = BCLINK_WIN_MIN;
591 if (max_win > TIPC_MAX_LINK_WIN)
593 tipc_bcast_lock(net);
594 tipc_link_set_queue_limits(l, tipc_link_min_win(l), max_win);
595 tipc_bcast_unlock(net);
599 static int tipc_bc_link_set_broadcast_mode(struct net *net, u32 bc_mode)
601 struct tipc_bc_base *bb = tipc_bc_base(net);
604 case BCLINK_MODE_BCAST:
605 if (!bb->bcast_support)
608 bb->force_bcast = true;
609 bb->force_rcast = false;
611 case BCLINK_MODE_RCAST:
612 if (!bb->rcast_support)
615 bb->force_bcast = false;
616 bb->force_rcast = true;
618 case BCLINK_MODE_SEL:
619 if (!bb->bcast_support || !bb->rcast_support)
622 bb->force_bcast = false;
623 bb->force_rcast = false;
632 static int tipc_bc_link_set_broadcast_ratio(struct net *net, u32 bc_ratio)
634 struct tipc_bc_base *bb = tipc_bc_base(net);
636 if (!bb->bcast_support || !bb->rcast_support)
639 if (bc_ratio > 100 || bc_ratio <= 0)
642 bb->rc_ratio = bc_ratio;
643 tipc_bcast_lock(net);
644 tipc_bcbase_calc_bc_threshold(net);
645 tipc_bcast_unlock(net);
650 int tipc_nl_bc_link_set(struct net *net, struct nlattr *attrs[])
656 struct nlattr *props[TIPC_NLA_PROP_MAX + 1];
658 if (!attrs[TIPC_NLA_LINK_PROP])
661 err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props);
665 if (!props[TIPC_NLA_PROP_WIN] &&
666 !props[TIPC_NLA_PROP_BROADCAST] &&
667 !props[TIPC_NLA_PROP_BROADCAST_RATIO]) {
671 if (props[TIPC_NLA_PROP_BROADCAST]) {
672 bc_mode = nla_get_u32(props[TIPC_NLA_PROP_BROADCAST]);
673 err = tipc_bc_link_set_broadcast_mode(net, bc_mode);
676 if (!err && props[TIPC_NLA_PROP_BROADCAST_RATIO]) {
677 bc_ratio = nla_get_u32(props[TIPC_NLA_PROP_BROADCAST_RATIO]);
678 err = tipc_bc_link_set_broadcast_ratio(net, bc_ratio);
681 if (!err && props[TIPC_NLA_PROP_WIN]) {
682 win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
683 err = tipc_bc_link_set_queue_limits(net, win);
689 int tipc_bcast_init(struct net *net)
691 struct tipc_net *tn = tipc_net(net);
692 struct tipc_bc_base *bb = NULL;
693 struct tipc_link *l = NULL;
695 bb = kzalloc(sizeof(*bb), GFP_KERNEL);
699 spin_lock_init(&tipc_net(net)->bclock);
701 if (!tipc_link_bc_create(net, 0, 0, NULL,
714 bb->rcast_support = true;
722 void tipc_bcast_stop(struct net *net)
724 struct tipc_net *tn = net_generic(net, tipc_net_id);
731 void tipc_nlist_init(struct tipc_nlist *nl, u32 self)
733 memset(nl, 0, sizeof(*nl));
734 INIT_LIST_HEAD(&nl->list);
738 void tipc_nlist_add(struct tipc_nlist *nl, u32 node)
740 if (node == nl->self)
742 else if (tipc_dest_push(&nl->list, node, 0))
746 void tipc_nlist_del(struct tipc_nlist *nl, u32 node)
748 if (node == nl->self)
750 else if (tipc_dest_del(&nl->list, node, 0))
754 void tipc_nlist_purge(struct tipc_nlist *nl)
756 tipc_dest_list_purge(&nl->list);
761 u32 tipc_bcast_get_mode(struct net *net)
763 struct tipc_bc_base *bb = tipc_bc_base(net);
766 return BCLINK_MODE_BCAST;
769 return BCLINK_MODE_RCAST;
771 if (bb->bcast_support && bb->rcast_support)
772 return BCLINK_MODE_SEL;
777 u32 tipc_bcast_get_broadcast_ratio(struct net *net)
779 struct tipc_bc_base *bb = tipc_bc_base(net);
784 void tipc_mcast_filter_msg(struct net *net, struct sk_buff_head *defq,
785 struct sk_buff_head *inputq)
787 struct sk_buff *skb, *_skb, *tmp;
788 struct tipc_msg *hdr, *_hdr;
792 skb = skb_peek(inputq);
798 if (likely(!msg_is_syn(hdr) && skb_queue_empty(defq)))
801 node = msg_orignode(hdr);
802 if (node == tipc_own_addr(net))
805 port = msg_origport(hdr);
807 /* Has the twin SYN message already arrived ? */
808 skb_queue_walk(defq, _skb) {
809 _hdr = buf_msg(_skb);
810 if (msg_orignode(_hdr) != node)
812 if (msg_origport(_hdr) != port)
819 if (!msg_is_syn(hdr))
821 __skb_dequeue(inputq);
822 __skb_queue_tail(defq, skb);
826 /* Deliver non-SYN message from other link, otherwise queue it */
827 if (!msg_is_syn(hdr)) {
828 if (msg_is_rcast(hdr) != msg_is_rcast(_hdr))
830 __skb_dequeue(inputq);
831 __skb_queue_tail(defq, skb);
835 /* Queue non-SYN/SYN message from same link */
836 if (msg_is_rcast(hdr) == msg_is_rcast(_hdr)) {
837 __skb_dequeue(inputq);
838 __skb_queue_tail(defq, skb);
842 /* Matching SYN messages => return the one with data, if any */
843 __skb_unlink(_skb, defq);
844 if (msg_data_sz(hdr)) {
847 __skb_dequeue(inputq);
849 __skb_queue_tail(inputq, _skb);
852 /* Deliver subsequent non-SYN messages from same peer */
853 skb_queue_walk_safe(defq, _skb, tmp) {
854 _hdr = buf_msg(_skb);
855 if (msg_orignode(_hdr) != node)
857 if (msg_origport(_hdr) != port)
859 if (msg_is_syn(_hdr))
861 __skb_unlink(_skb, defq);
862 __skb_queue_tail(inputq, _skb);