Merge tag 'iio-for-4.10a' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23...
[linux/fpc-iii.git] / net / tipc / msg.h
blobc3832cdf2278a3a49dd6624d350ba34096764897
1 /*
2 * net/tipc/msg.h: Include file for TIPC message header routines
4 * Copyright (c) 2000-2007, 2014-2015 Ericsson AB
5 * Copyright (c) 2005-2008, 2010-2011, Wind River Systems
6 * All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the names of the copyright holders nor the names of its
17 * contributors may be used to endorse or promote products derived from
18 * this software without specific prior written permission.
20 * Alternatively, this software may be distributed under the terms of the
21 * GNU General Public License ("GPL") version 2 as published by the Free
22 * Software Foundation.
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
25 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
28 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
29 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
30 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
31 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
32 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34 * POSSIBILITY OF SUCH DAMAGE.
37 #ifndef _TIPC_MSG_H
38 #define _TIPC_MSG_H
40 #include <linux/tipc.h>
41 #include "core.h"
44 * Constants and routines used to read and write TIPC payload message headers
46 * Note: Some items are also used with TIPC internal message headers
48 #define TIPC_VERSION 2
49 struct plist;
52 * Payload message users are defined in TIPC's public API:
53 * - TIPC_LOW_IMPORTANCE
54 * - TIPC_MEDIUM_IMPORTANCE
55 * - TIPC_HIGH_IMPORTANCE
56 * - TIPC_CRITICAL_IMPORTANCE
58 #define TIPC_SYSTEM_IMPORTANCE 4
62 * Payload message types
64 #define TIPC_CONN_MSG 0
65 #define TIPC_MCAST_MSG 1
66 #define TIPC_NAMED_MSG 2
67 #define TIPC_DIRECT_MSG 3
70 * Internal message users
72 #define BCAST_PROTOCOL 5
73 #define MSG_BUNDLER 6
74 #define LINK_PROTOCOL 7
75 #define CONN_MANAGER 8
76 #define TUNNEL_PROTOCOL 10
77 #define NAME_DISTRIBUTOR 11
78 #define MSG_FRAGMENTER 12
79 #define LINK_CONFIG 13
80 #define SOCK_WAKEUP 14 /* pseudo user */
83 * Message header sizes
85 #define SHORT_H_SIZE 24 /* In-cluster basic payload message */
86 #define BASIC_H_SIZE 32 /* Basic payload message */
87 #define NAMED_H_SIZE 40 /* Named payload message */
88 #define MCAST_H_SIZE 44 /* Multicast payload message */
89 #define INT_H_SIZE 40 /* Internal messages */
90 #define MIN_H_SIZE 24 /* Smallest legal TIPC header size */
91 #define MAX_H_SIZE 60 /* Largest possible TIPC header size */
93 #define MAX_MSG_SIZE (MAX_H_SIZE + TIPC_MAX_USER_MSG_SIZE)
95 #define TIPC_MEDIA_INFO_OFFSET 5
97 struct tipc_skb_cb {
98 void *handle;
99 struct sk_buff *tail;
100 bool validated;
101 bool wakeup_pending;
102 u16 chain_sz;
103 u16 chain_imp;
104 u16 ackers;
107 #define TIPC_SKB_CB(__skb) ((struct tipc_skb_cb *)&((__skb)->cb[0]))
109 struct tipc_msg {
110 __be32 hdr[15];
113 static inline struct tipc_msg *buf_msg(struct sk_buff *skb)
115 return (struct tipc_msg *)skb->data;
118 static inline u32 msg_word(struct tipc_msg *m, u32 pos)
120 return ntohl(m->hdr[pos]);
123 static inline void msg_set_word(struct tipc_msg *m, u32 w, u32 val)
125 m->hdr[w] = htonl(val);
128 static inline u32 msg_bits(struct tipc_msg *m, u32 w, u32 pos, u32 mask)
130 return (msg_word(m, w) >> pos) & mask;
133 static inline void msg_set_bits(struct tipc_msg *m, u32 w,
134 u32 pos, u32 mask, u32 val)
136 val = (val & mask) << pos;
137 mask = mask << pos;
138 m->hdr[w] &= ~htonl(mask);
139 m->hdr[w] |= htonl(val);
142 static inline void msg_swap_words(struct tipc_msg *msg, u32 a, u32 b)
144 u32 temp = msg->hdr[a];
146 msg->hdr[a] = msg->hdr[b];
147 msg->hdr[b] = temp;
151 * Word 0
153 static inline u32 msg_version(struct tipc_msg *m)
155 return msg_bits(m, 0, 29, 7);
158 static inline void msg_set_version(struct tipc_msg *m)
160 msg_set_bits(m, 0, 29, 7, TIPC_VERSION);
163 static inline u32 msg_user(struct tipc_msg *m)
165 return msg_bits(m, 0, 25, 0xf);
168 static inline u32 msg_isdata(struct tipc_msg *m)
170 return msg_user(m) <= TIPC_CRITICAL_IMPORTANCE;
173 static inline void msg_set_user(struct tipc_msg *m, u32 n)
175 msg_set_bits(m, 0, 25, 0xf, n);
178 static inline u32 msg_hdr_sz(struct tipc_msg *m)
180 return msg_bits(m, 0, 21, 0xf) << 2;
183 static inline void msg_set_hdr_sz(struct tipc_msg *m, u32 n)
185 msg_set_bits(m, 0, 21, 0xf, n>>2);
188 static inline u32 msg_size(struct tipc_msg *m)
190 return msg_bits(m, 0, 0, 0x1ffff);
193 static inline u32 msg_data_sz(struct tipc_msg *m)
195 return msg_size(m) - msg_hdr_sz(m);
198 static inline int msg_non_seq(struct tipc_msg *m)
200 return msg_bits(m, 0, 20, 1);
203 static inline void msg_set_non_seq(struct tipc_msg *m, u32 n)
205 msg_set_bits(m, 0, 20, 1, n);
208 static inline int msg_dest_droppable(struct tipc_msg *m)
210 return msg_bits(m, 0, 19, 1);
213 static inline void msg_set_dest_droppable(struct tipc_msg *m, u32 d)
215 msg_set_bits(m, 0, 19, 1, d);
218 static inline int msg_src_droppable(struct tipc_msg *m)
220 return msg_bits(m, 0, 18, 1);
223 static inline void msg_set_src_droppable(struct tipc_msg *m, u32 d)
225 msg_set_bits(m, 0, 18, 1, d);
228 static inline void msg_set_size(struct tipc_msg *m, u32 sz)
230 m->hdr[0] = htonl((msg_word(m, 0) & ~0x1ffff) | sz);
233 static inline unchar *msg_data(struct tipc_msg *m)
235 return ((unchar *)m) + msg_hdr_sz(m);
238 static inline struct tipc_msg *msg_get_wrapped(struct tipc_msg *m)
240 return (struct tipc_msg *)msg_data(m);
244 * Word 1
246 static inline u32 msg_type(struct tipc_msg *m)
248 return msg_bits(m, 1, 29, 0x7);
251 static inline void msg_set_type(struct tipc_msg *m, u32 n)
253 msg_set_bits(m, 1, 29, 0x7, n);
256 static inline u32 msg_named(struct tipc_msg *m)
258 return msg_type(m) == TIPC_NAMED_MSG;
261 static inline u32 msg_mcast(struct tipc_msg *m)
263 return msg_type(m) == TIPC_MCAST_MSG;
266 static inline u32 msg_connected(struct tipc_msg *m)
268 return msg_type(m) == TIPC_CONN_MSG;
271 static inline u32 msg_errcode(struct tipc_msg *m)
273 return msg_bits(m, 1, 25, 0xf);
276 static inline void msg_set_errcode(struct tipc_msg *m, u32 err)
278 msg_set_bits(m, 1, 25, 0xf, err);
281 static inline u32 msg_reroute_cnt(struct tipc_msg *m)
283 return msg_bits(m, 1, 21, 0xf);
286 static inline void msg_incr_reroute_cnt(struct tipc_msg *m)
288 msg_set_bits(m, 1, 21, 0xf, msg_reroute_cnt(m) + 1);
291 static inline void msg_reset_reroute_cnt(struct tipc_msg *m)
293 msg_set_bits(m, 1, 21, 0xf, 0);
296 static inline u32 msg_lookup_scope(struct tipc_msg *m)
298 return msg_bits(m, 1, 19, 0x3);
301 static inline void msg_set_lookup_scope(struct tipc_msg *m, u32 n)
303 msg_set_bits(m, 1, 19, 0x3, n);
306 static inline u16 msg_bcast_ack(struct tipc_msg *m)
308 return msg_bits(m, 1, 0, 0xffff);
311 static inline void msg_set_bcast_ack(struct tipc_msg *m, u16 n)
313 msg_set_bits(m, 1, 0, 0xffff, n);
318 * Word 2
320 static inline u16 msg_ack(struct tipc_msg *m)
322 return msg_bits(m, 2, 16, 0xffff);
325 static inline void msg_set_ack(struct tipc_msg *m, u16 n)
327 msg_set_bits(m, 2, 16, 0xffff, n);
330 static inline u16 msg_seqno(struct tipc_msg *m)
332 return msg_bits(m, 2, 0, 0xffff);
335 static inline void msg_set_seqno(struct tipc_msg *m, u16 n)
337 msg_set_bits(m, 2, 0, 0xffff, n);
341 * Words 3-10
343 static inline u32 msg_importance(struct tipc_msg *m)
345 int usr = msg_user(m);
347 if (likely((usr <= TIPC_CRITICAL_IMPORTANCE) && !msg_errcode(m)))
348 return usr;
349 if ((usr == MSG_FRAGMENTER) || (usr == MSG_BUNDLER))
350 return msg_bits(m, 9, 0, 0x7);
351 return TIPC_SYSTEM_IMPORTANCE;
354 static inline void msg_set_importance(struct tipc_msg *m, u32 i)
356 int usr = msg_user(m);
358 if (likely((usr == MSG_FRAGMENTER) || (usr == MSG_BUNDLER)))
359 msg_set_bits(m, 9, 0, 0x7, i);
360 else if (i < TIPC_SYSTEM_IMPORTANCE)
361 msg_set_user(m, i);
362 else
363 pr_warn("Trying to set illegal importance in message\n");
366 static inline u32 msg_prevnode(struct tipc_msg *m)
368 return msg_word(m, 3);
371 static inline void msg_set_prevnode(struct tipc_msg *m, u32 a)
373 msg_set_word(m, 3, a);
376 static inline u32 msg_origport(struct tipc_msg *m)
378 if (msg_user(m) == MSG_FRAGMENTER)
379 m = msg_get_wrapped(m);
380 return msg_word(m, 4);
383 static inline void msg_set_origport(struct tipc_msg *m, u32 p)
385 msg_set_word(m, 4, p);
388 static inline u32 msg_destport(struct tipc_msg *m)
390 return msg_word(m, 5);
393 static inline void msg_set_destport(struct tipc_msg *m, u32 p)
395 msg_set_word(m, 5, p);
398 static inline u32 msg_mc_netid(struct tipc_msg *m)
400 return msg_word(m, 5);
403 static inline void msg_set_mc_netid(struct tipc_msg *m, u32 p)
405 msg_set_word(m, 5, p);
408 static inline int msg_short(struct tipc_msg *m)
410 return msg_hdr_sz(m) == SHORT_H_SIZE;
413 static inline u32 msg_orignode(struct tipc_msg *m)
415 if (likely(msg_short(m)))
416 return msg_prevnode(m);
417 return msg_word(m, 6);
420 static inline void msg_set_orignode(struct tipc_msg *m, u32 a)
422 msg_set_word(m, 6, a);
425 static inline u32 msg_destnode(struct tipc_msg *m)
427 return msg_word(m, 7);
430 static inline void msg_set_destnode(struct tipc_msg *m, u32 a)
432 msg_set_word(m, 7, a);
435 static inline u32 msg_nametype(struct tipc_msg *m)
437 return msg_word(m, 8);
440 static inline void msg_set_nametype(struct tipc_msg *m, u32 n)
442 msg_set_word(m, 8, n);
445 static inline u32 msg_nameinst(struct tipc_msg *m)
447 return msg_word(m, 9);
450 static inline u32 msg_namelower(struct tipc_msg *m)
452 return msg_nameinst(m);
455 static inline void msg_set_namelower(struct tipc_msg *m, u32 n)
457 msg_set_word(m, 9, n);
460 static inline void msg_set_nameinst(struct tipc_msg *m, u32 n)
462 msg_set_namelower(m, n);
465 static inline u32 msg_nameupper(struct tipc_msg *m)
467 return msg_word(m, 10);
470 static inline void msg_set_nameupper(struct tipc_msg *m, u32 n)
472 msg_set_word(m, 10, n);
476 * Constants and routines used to read and write TIPC internal message headers
480 * Connection management protocol message types
482 #define CONN_PROBE 0
483 #define CONN_PROBE_REPLY 1
484 #define CONN_ACK 2
487 * Name distributor message types
489 #define PUBLICATION 0
490 #define WITHDRAWAL 1
493 * Segmentation message types
495 #define FIRST_FRAGMENT 0
496 #define FRAGMENT 1
497 #define LAST_FRAGMENT 2
500 * Link management protocol message types
502 #define STATE_MSG 0
503 #define RESET_MSG 1
504 #define ACTIVATE_MSG 2
507 * Changeover tunnel message types
509 #define SYNCH_MSG 0
510 #define FAILOVER_MSG 1
513 * Config protocol message types
515 #define DSC_REQ_MSG 0
516 #define DSC_RESP_MSG 1
519 * Word 1
521 static inline u32 msg_seq_gap(struct tipc_msg *m)
523 return msg_bits(m, 1, 16, 0x1fff);
526 static inline void msg_set_seq_gap(struct tipc_msg *m, u32 n)
528 msg_set_bits(m, 1, 16, 0x1fff, n);
531 static inline u32 msg_node_sig(struct tipc_msg *m)
533 return msg_bits(m, 1, 0, 0xffff);
536 static inline void msg_set_node_sig(struct tipc_msg *m, u32 n)
538 msg_set_bits(m, 1, 0, 0xffff, n);
541 static inline u32 msg_node_capabilities(struct tipc_msg *m)
543 return msg_bits(m, 1, 15, 0x1fff);
546 static inline void msg_set_node_capabilities(struct tipc_msg *m, u32 n)
548 msg_set_bits(m, 1, 15, 0x1fff, n);
552 * Word 2
554 static inline u32 msg_dest_domain(struct tipc_msg *m)
556 return msg_word(m, 2);
559 static inline void msg_set_dest_domain(struct tipc_msg *m, u32 n)
561 msg_set_word(m, 2, n);
564 static inline u32 msg_bcgap_after(struct tipc_msg *m)
566 return msg_bits(m, 2, 16, 0xffff);
569 static inline void msg_set_bcgap_after(struct tipc_msg *m, u32 n)
571 msg_set_bits(m, 2, 16, 0xffff, n);
574 static inline u32 msg_bcgap_to(struct tipc_msg *m)
576 return msg_bits(m, 2, 0, 0xffff);
579 static inline void msg_set_bcgap_to(struct tipc_msg *m, u32 n)
581 msg_set_bits(m, 2, 0, 0xffff, n);
586 * Word 4
588 static inline u32 msg_last_bcast(struct tipc_msg *m)
590 return msg_bits(m, 4, 16, 0xffff);
593 static inline u32 msg_bc_snd_nxt(struct tipc_msg *m)
595 return msg_last_bcast(m) + 1;
598 static inline void msg_set_last_bcast(struct tipc_msg *m, u32 n)
600 msg_set_bits(m, 4, 16, 0xffff, n);
603 static inline void msg_set_fragm_no(struct tipc_msg *m, u32 n)
605 msg_set_bits(m, 4, 16, 0xffff, n);
609 static inline u16 msg_next_sent(struct tipc_msg *m)
611 return msg_bits(m, 4, 0, 0xffff);
614 static inline void msg_set_next_sent(struct tipc_msg *m, u16 n)
616 msg_set_bits(m, 4, 0, 0xffff, n);
619 static inline void msg_set_long_msgno(struct tipc_msg *m, u32 n)
621 msg_set_bits(m, 4, 0, 0xffff, n);
624 static inline u32 msg_bc_netid(struct tipc_msg *m)
626 return msg_word(m, 4);
629 static inline void msg_set_bc_netid(struct tipc_msg *m, u32 id)
631 msg_set_word(m, 4, id);
634 static inline u32 msg_link_selector(struct tipc_msg *m)
636 return msg_bits(m, 4, 0, 1);
639 static inline void msg_set_link_selector(struct tipc_msg *m, u32 n)
641 msg_set_bits(m, 4, 0, 1, n);
645 * Word 5
647 static inline u16 msg_session(struct tipc_msg *m)
649 return msg_bits(m, 5, 16, 0xffff);
652 static inline void msg_set_session(struct tipc_msg *m, u16 n)
654 msg_set_bits(m, 5, 16, 0xffff, n);
657 static inline u32 msg_probe(struct tipc_msg *m)
659 return msg_bits(m, 5, 0, 1);
662 static inline void msg_set_probe(struct tipc_msg *m, u32 val)
664 msg_set_bits(m, 5, 0, 1, val);
667 static inline char msg_net_plane(struct tipc_msg *m)
669 return msg_bits(m, 5, 1, 7) + 'A';
672 static inline void msg_set_net_plane(struct tipc_msg *m, char n)
674 msg_set_bits(m, 5, 1, 7, (n - 'A'));
677 static inline u32 msg_linkprio(struct tipc_msg *m)
679 return msg_bits(m, 5, 4, 0x1f);
682 static inline void msg_set_linkprio(struct tipc_msg *m, u32 n)
684 msg_set_bits(m, 5, 4, 0x1f, n);
687 static inline u32 msg_bearer_id(struct tipc_msg *m)
689 return msg_bits(m, 5, 9, 0x7);
692 static inline void msg_set_bearer_id(struct tipc_msg *m, u32 n)
694 msg_set_bits(m, 5, 9, 0x7, n);
697 static inline u32 msg_redundant_link(struct tipc_msg *m)
699 return msg_bits(m, 5, 12, 0x1);
702 static inline void msg_set_redundant_link(struct tipc_msg *m, u32 r)
704 msg_set_bits(m, 5, 12, 0x1, r);
707 static inline u32 msg_peer_stopping(struct tipc_msg *m)
709 return msg_bits(m, 5, 13, 0x1);
712 static inline void msg_set_peer_stopping(struct tipc_msg *m, u32 s)
714 msg_set_bits(m, 5, 13, 0x1, s);
717 static inline char *msg_media_addr(struct tipc_msg *m)
719 return (char *)&m->hdr[TIPC_MEDIA_INFO_OFFSET];
722 static inline u32 msg_bc_gap(struct tipc_msg *m)
724 return msg_bits(m, 8, 0, 0x3ff);
727 static inline void msg_set_bc_gap(struct tipc_msg *m, u32 n)
729 msg_set_bits(m, 8, 0, 0x3ff, n);
733 * Word 9
735 static inline u16 msg_msgcnt(struct tipc_msg *m)
737 return msg_bits(m, 9, 16, 0xffff);
740 static inline void msg_set_msgcnt(struct tipc_msg *m, u16 n)
742 msg_set_bits(m, 9, 16, 0xffff, n);
745 static inline u32 msg_conn_ack(struct tipc_msg *m)
747 return msg_bits(m, 9, 16, 0xffff);
750 static inline void msg_set_conn_ack(struct tipc_msg *m, u32 n)
752 msg_set_bits(m, 9, 16, 0xffff, n);
755 static inline u32 msg_adv_win(struct tipc_msg *m)
757 return msg_bits(m, 9, 0, 0xffff);
760 static inline void msg_set_adv_win(struct tipc_msg *m, u32 n)
762 msg_set_bits(m, 9, 0, 0xffff, n);
765 static inline u32 msg_max_pkt(struct tipc_msg *m)
767 return msg_bits(m, 9, 16, 0xffff) * 4;
770 static inline void msg_set_max_pkt(struct tipc_msg *m, u32 n)
772 msg_set_bits(m, 9, 16, 0xffff, (n / 4));
775 static inline u32 msg_link_tolerance(struct tipc_msg *m)
777 return msg_bits(m, 9, 0, 0xffff);
780 static inline void msg_set_link_tolerance(struct tipc_msg *m, u32 n)
782 msg_set_bits(m, 9, 0, 0xffff, n);
785 static inline bool msg_peer_link_is_up(struct tipc_msg *m)
787 if (likely(msg_user(m) != LINK_PROTOCOL))
788 return true;
789 if (msg_type(m) == STATE_MSG)
790 return true;
791 return false;
794 static inline bool msg_peer_node_is_up(struct tipc_msg *m)
796 if (msg_peer_link_is_up(m))
797 return true;
798 return msg_redundant_link(m);
801 static inline bool msg_is_reset(struct tipc_msg *hdr)
803 return (msg_user(hdr) == LINK_PROTOCOL) && (msg_type(hdr) == RESET_MSG);
806 struct sk_buff *tipc_buf_acquire(u32 size);
807 bool tipc_msg_validate(struct sk_buff *skb);
808 bool tipc_msg_reverse(u32 own_addr, struct sk_buff **skb, int err);
809 void tipc_msg_init(u32 own_addr, struct tipc_msg *m, u32 user, u32 type,
810 u32 hsize, u32 destnode);
811 struct sk_buff *tipc_msg_create(uint user, uint type, uint hdr_sz,
812 uint data_sz, u32 dnode, u32 onode,
813 u32 dport, u32 oport, int errcode);
814 int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf);
815 bool tipc_msg_bundle(struct sk_buff *skb, struct tipc_msg *msg, u32 mtu);
816 bool tipc_msg_make_bundle(struct sk_buff **skb, struct tipc_msg *msg,
817 u32 mtu, u32 dnode);
818 bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos);
819 int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m,
820 int offset, int dsz, int mtu, struct sk_buff_head *list);
821 bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, int *err);
822 bool tipc_msg_reassemble(struct sk_buff_head *list, struct sk_buff_head *rcvq);
823 void __tipc_skb_queue_sorted(struct sk_buff_head *list, u16 seqno,
824 struct sk_buff *skb);
826 static inline u16 buf_seqno(struct sk_buff *skb)
828 return msg_seqno(buf_msg(skb));
831 /* tipc_skb_peek(): peek and reserve first buffer in list
832 * @list: list to be peeked in
833 * Returns pointer to first buffer in list, if any
835 static inline struct sk_buff *tipc_skb_peek(struct sk_buff_head *list,
836 spinlock_t *lock)
838 struct sk_buff *skb;
840 spin_lock_bh(lock);
841 skb = skb_peek(list);
842 if (skb)
843 skb_get(skb);
844 spin_unlock_bh(lock);
845 return skb;
848 /* tipc_skb_peek_port(): find a destination port, ignoring all destinations
849 * up to and including 'filter'.
850 * Note: ignoring previously tried destinations minimizes the risk of
851 * contention on the socket lock
852 * @list: list to be peeked in
853 * @filter: last destination to be ignored from search
854 * Returns a destination port number, of applicable.
856 static inline u32 tipc_skb_peek_port(struct sk_buff_head *list, u32 filter)
858 struct sk_buff *skb;
859 u32 dport = 0;
860 bool ignore = true;
862 spin_lock_bh(&list->lock);
863 skb_queue_walk(list, skb) {
864 dport = msg_destport(buf_msg(skb));
865 if (!filter || skb_queue_is_last(list, skb))
866 break;
867 if (dport == filter)
868 ignore = false;
869 else if (!ignore)
870 break;
872 spin_unlock_bh(&list->lock);
873 return dport;
876 /* tipc_skb_dequeue(): unlink first buffer with dest 'dport' from list
877 * @list: list to be unlinked from
878 * @dport: selection criteria for buffer to unlink
880 static inline struct sk_buff *tipc_skb_dequeue(struct sk_buff_head *list,
881 u32 dport)
883 struct sk_buff *_skb, *tmp, *skb = NULL;
885 spin_lock_bh(&list->lock);
886 skb_queue_walk_safe(list, _skb, tmp) {
887 if (msg_destport(buf_msg(_skb)) == dport) {
888 __skb_unlink(_skb, list);
889 skb = _skb;
890 break;
893 spin_unlock_bh(&list->lock);
894 return skb;
897 /* tipc_skb_queue_splice_tail - append an skb list to lock protected list
898 * @list: the new list to append. Not lock protected
899 * @head: target list. Lock protected.
901 static inline void tipc_skb_queue_splice_tail(struct sk_buff_head *list,
902 struct sk_buff_head *head)
904 spin_lock_bh(&head->lock);
905 skb_queue_splice_tail(list, head);
906 spin_unlock_bh(&head->lock);
909 /* tipc_skb_queue_splice_tail_init - merge two lock protected skb lists
910 * @list: the new list to add. Lock protected. Will be reinitialized
911 * @head: target list. Lock protected.
913 static inline void tipc_skb_queue_splice_tail_init(struct sk_buff_head *list,
914 struct sk_buff_head *head)
916 struct sk_buff_head tmp;
918 __skb_queue_head_init(&tmp);
920 spin_lock_bh(&list->lock);
921 skb_queue_splice_tail_init(list, &tmp);
922 spin_unlock_bh(&list->lock);
923 tipc_skb_queue_splice_tail(&tmp, head);
926 #endif