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1/* 2 * net/tipc/msg.h: Include file for TIPC message header routines 3 * 4 * Copyright (c) 2000-2007, 2014, Ericsson AB 5 * Copyright (c) 2005-2008, 2010-2011, Wind River Systems 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions are met: 10 * 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. 19 * 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. 23 * 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. 35 */ 36 37#ifndef _TIPC_MSG_H 38#define _TIPC_MSG_H 39 40#include <linux/tipc.h> 41 42/* 43 * Constants and routines used to read and write TIPC payload message headers 44 * 45 * Note: Some items are also used with TIPC internal message headers 46 */ 47#define TIPC_VERSION 2 48struct plist; 49 50/* 51 * Payload message users are defined in TIPC's public API: 52 * - TIPC_LOW_IMPORTANCE 53 * - TIPC_MEDIUM_IMPORTANCE 54 * - TIPC_HIGH_IMPORTANCE 55 * - TIPC_CRITICAL_IMPORTANCE 56 */ 57 58/* 59 * Payload message types 60 */ 61#define TIPC_CONN_MSG 0 62#define TIPC_MCAST_MSG 1 63#define TIPC_NAMED_MSG 2 64#define TIPC_DIRECT_MSG 3 65 66/* 67 * Message header sizes 68 */ 69#define SHORT_H_SIZE 24 /* In-cluster basic payload message */ 70#define BASIC_H_SIZE 32 /* Basic payload message */ 71#define NAMED_H_SIZE 40 /* Named payload message */ 72#define MCAST_H_SIZE 44 /* Multicast payload message */ 73#define INT_H_SIZE 40 /* Internal messages */ 74#define MIN_H_SIZE 24 /* Smallest legal TIPC header size */ 75#define MAX_H_SIZE 60 /* Largest possible TIPC header size */ 76 77#define MAX_MSG_SIZE (MAX_H_SIZE + TIPC_MAX_USER_MSG_SIZE) 78 79#define TIPC_MEDIA_ADDR_OFFSET 5 80 81/** 82 * TIPC message buffer code 83 * 84 * TIPC message buffer headroom reserves space for the worst-case 85 * link-level device header (in case the message is sent off-node). 86 * 87 * Note: Headroom should be a multiple of 4 to ensure the TIPC header fields 88 * are word aligned for quicker access 89 */ 90#define BUF_HEADROOM LL_MAX_HEADER 91 92struct tipc_skb_cb { 93 void *handle; 94 struct sk_buff *tail; 95 bool deferred; 96 bool wakeup_pending; 97 bool bundling; 98 u16 chain_sz; 99 u16 chain_imp; 100}; 101 102#define TIPC_SKB_CB(__skb) ((struct tipc_skb_cb *)&((__skb)->cb[0])) 103 104struct tipc_msg { 105 __be32 hdr[15]; 106}; 107 108static inline struct tipc_msg *buf_msg(struct sk_buff *skb) 109{ 110 return (struct tipc_msg *)skb->data; 111} 112 113static inline u32 msg_word(struct tipc_msg *m, u32 pos) 114{ 115 return ntohl(m->hdr[pos]); 116} 117 118static inline void msg_set_word(struct tipc_msg *m, u32 w, u32 val) 119{ 120 m->hdr[w] = htonl(val); 121} 122 123static inline u32 msg_bits(struct tipc_msg *m, u32 w, u32 pos, u32 mask) 124{ 125 return (msg_word(m, w) >> pos) & mask; 126} 127 128static inline void msg_set_bits(struct tipc_msg *m, u32 w, 129 u32 pos, u32 mask, u32 val) 130{ 131 val = (val & mask) << pos; 132 mask = mask << pos; 133 m->hdr[w] &= ~htonl(mask); 134 m->hdr[w] |= htonl(val); 135} 136 137static inline void msg_swap_words(struct tipc_msg *msg, u32 a, u32 b) 138{ 139 u32 temp = msg->hdr[a]; 140 141 msg->hdr[a] = msg->hdr[b]; 142 msg->hdr[b] = temp; 143} 144 145/* 146 * Word 0 147 */ 148static inline u32 msg_version(struct tipc_msg *m) 149{ 150 return msg_bits(m, 0, 29, 7); 151} 152 153static inline void msg_set_version(struct tipc_msg *m) 154{ 155 msg_set_bits(m, 0, 29, 7, TIPC_VERSION); 156} 157 158static inline u32 msg_user(struct tipc_msg *m) 159{ 160 return msg_bits(m, 0, 25, 0xf); 161} 162 163static inline u32 msg_isdata(struct tipc_msg *m) 164{ 165 return msg_user(m) <= TIPC_CRITICAL_IMPORTANCE; 166} 167 168static inline void msg_set_user(struct tipc_msg *m, u32 n) 169{ 170 msg_set_bits(m, 0, 25, 0xf, n); 171} 172 173static inline u32 msg_importance(struct tipc_msg *m) 174{ 175 return msg_bits(m, 0, 25, 0xf); 176} 177 178static inline void msg_set_importance(struct tipc_msg *m, u32 i) 179{ 180 msg_set_user(m, i); 181} 182 183static inline u32 msg_hdr_sz(struct tipc_msg *m) 184{ 185 return msg_bits(m, 0, 21, 0xf) << 2; 186} 187 188static inline void msg_set_hdr_sz(struct tipc_msg *m, u32 n) 189{ 190 msg_set_bits(m, 0, 21, 0xf, n>>2); 191} 192 193static inline u32 msg_size(struct tipc_msg *m) 194{ 195 return msg_bits(m, 0, 0, 0x1ffff); 196} 197 198static inline u32 msg_data_sz(struct tipc_msg *m) 199{ 200 return msg_size(m) - msg_hdr_sz(m); 201} 202 203static inline int msg_non_seq(struct tipc_msg *m) 204{ 205 return msg_bits(m, 0, 20, 1); 206} 207 208static inline void msg_set_non_seq(struct tipc_msg *m, u32 n) 209{ 210 msg_set_bits(m, 0, 20, 1, n); 211} 212 213static inline int msg_dest_droppable(struct tipc_msg *m) 214{ 215 return msg_bits(m, 0, 19, 1); 216} 217 218static inline void msg_set_dest_droppable(struct tipc_msg *m, u32 d) 219{ 220 msg_set_bits(m, 0, 19, 1, d); 221} 222 223static inline int msg_src_droppable(struct tipc_msg *m) 224{ 225 return msg_bits(m, 0, 18, 1); 226} 227 228static inline void msg_set_src_droppable(struct tipc_msg *m, u32 d) 229{ 230 msg_set_bits(m, 0, 18, 1, d); 231} 232 233static inline void msg_set_size(struct tipc_msg *m, u32 sz) 234{ 235 m->hdr[0] = htonl((msg_word(m, 0) & ~0x1ffff) | sz); 236} 237 238 239/* 240 * Word 1 241 */ 242static inline u32 msg_type(struct tipc_msg *m) 243{ 244 return msg_bits(m, 1, 29, 0x7); 245} 246 247static inline void msg_set_type(struct tipc_msg *m, u32 n) 248{ 249 msg_set_bits(m, 1, 29, 0x7, n); 250} 251 252static inline u32 msg_named(struct tipc_msg *m) 253{ 254 return msg_type(m) == TIPC_NAMED_MSG; 255} 256 257static inline u32 msg_mcast(struct tipc_msg *m) 258{ 259 return msg_type(m) == TIPC_MCAST_MSG; 260} 261 262static inline u32 msg_connected(struct tipc_msg *m) 263{ 264 return msg_type(m) == TIPC_CONN_MSG; 265} 266 267static inline u32 msg_errcode(struct tipc_msg *m) 268{ 269 return msg_bits(m, 1, 25, 0xf); 270} 271 272static inline void msg_set_errcode(struct tipc_msg *m, u32 err) 273{ 274 msg_set_bits(m, 1, 25, 0xf, err); 275} 276 277static inline u32 msg_reroute_cnt(struct tipc_msg *m) 278{ 279 return msg_bits(m, 1, 21, 0xf); 280} 281 282static inline void msg_incr_reroute_cnt(struct tipc_msg *m) 283{ 284 msg_set_bits(m, 1, 21, 0xf, msg_reroute_cnt(m) + 1); 285} 286 287static inline void msg_reset_reroute_cnt(struct tipc_msg *m) 288{ 289 msg_set_bits(m, 1, 21, 0xf, 0); 290} 291 292static inline u32 msg_lookup_scope(struct tipc_msg *m) 293{ 294 return msg_bits(m, 1, 19, 0x3); 295} 296 297static inline void msg_set_lookup_scope(struct tipc_msg *m, u32 n) 298{ 299 msg_set_bits(m, 1, 19, 0x3, n); 300} 301 302static inline u32 msg_bcast_ack(struct tipc_msg *m) 303{ 304 return msg_bits(m, 1, 0, 0xffff); 305} 306 307static inline void msg_set_bcast_ack(struct tipc_msg *m, u32 n) 308{ 309 msg_set_bits(m, 1, 0, 0xffff, n); 310} 311 312 313/* 314 * Word 2 315 */ 316static inline u32 msg_ack(struct tipc_msg *m) 317{ 318 return msg_bits(m, 2, 16, 0xffff); 319} 320 321static inline void msg_set_ack(struct tipc_msg *m, u32 n) 322{ 323 msg_set_bits(m, 2, 16, 0xffff, n); 324} 325 326static inline u32 msg_seqno(struct tipc_msg *m) 327{ 328 return msg_bits(m, 2, 0, 0xffff); 329} 330 331static inline void msg_set_seqno(struct tipc_msg *m, u32 n) 332{ 333 msg_set_bits(m, 2, 0, 0xffff, n); 334} 335 336/* 337 * Words 3-10 338 */ 339static inline u32 msg_prevnode(struct tipc_msg *m) 340{ 341 return msg_word(m, 3); 342} 343 344static inline void msg_set_prevnode(struct tipc_msg *m, u32 a) 345{ 346 msg_set_word(m, 3, a); 347} 348 349static inline u32 msg_origport(struct tipc_msg *m) 350{ 351 return msg_word(m, 4); 352} 353 354static inline void msg_set_origport(struct tipc_msg *m, u32 p) 355{ 356 msg_set_word(m, 4, p); 357} 358 359static inline u32 msg_destport(struct tipc_msg *m) 360{ 361 return msg_word(m, 5); 362} 363 364static inline void msg_set_destport(struct tipc_msg *m, u32 p) 365{ 366 msg_set_word(m, 5, p); 367} 368 369static inline u32 msg_mc_netid(struct tipc_msg *m) 370{ 371 return msg_word(m, 5); 372} 373 374static inline void msg_set_mc_netid(struct tipc_msg *m, u32 p) 375{ 376 msg_set_word(m, 5, p); 377} 378 379static inline int msg_short(struct tipc_msg *m) 380{ 381 return msg_hdr_sz(m) == SHORT_H_SIZE; 382} 383 384static inline u32 msg_orignode(struct tipc_msg *m) 385{ 386 if (likely(msg_short(m))) 387 return msg_prevnode(m); 388 return msg_word(m, 6); 389} 390 391static inline void msg_set_orignode(struct tipc_msg *m, u32 a) 392{ 393 msg_set_word(m, 6, a); 394} 395 396static inline u32 msg_destnode(struct tipc_msg *m) 397{ 398 return msg_word(m, 7); 399} 400 401static inline void msg_set_destnode(struct tipc_msg *m, u32 a) 402{ 403 msg_set_word(m, 7, a); 404} 405 406static inline u32 msg_nametype(struct tipc_msg *m) 407{ 408 return msg_word(m, 8); 409} 410 411static inline void msg_set_nametype(struct tipc_msg *m, u32 n) 412{ 413 msg_set_word(m, 8, n); 414} 415 416static inline u32 msg_nameinst(struct tipc_msg *m) 417{ 418 return msg_word(m, 9); 419} 420 421static inline u32 msg_namelower(struct tipc_msg *m) 422{ 423 return msg_nameinst(m); 424} 425 426static inline void msg_set_namelower(struct tipc_msg *m, u32 n) 427{ 428 msg_set_word(m, 9, n); 429} 430 431static inline void msg_set_nameinst(struct tipc_msg *m, u32 n) 432{ 433 msg_set_namelower(m, n); 434} 435 436static inline u32 msg_nameupper(struct tipc_msg *m) 437{ 438 return msg_word(m, 10); 439} 440 441static inline void msg_set_nameupper(struct tipc_msg *m, u32 n) 442{ 443 msg_set_word(m, 10, n); 444} 445 446static inline unchar *msg_data(struct tipc_msg *m) 447{ 448 return ((unchar *)m) + msg_hdr_sz(m); 449} 450 451static inline struct tipc_msg *msg_get_wrapped(struct tipc_msg *m) 452{ 453 return (struct tipc_msg *)msg_data(m); 454} 455 456/* 457 * Constants and routines used to read and write TIPC internal message headers 458 */ 459 460/* 461 * Internal message users 462 */ 463#define BCAST_PROTOCOL 5 464#define MSG_BUNDLER 6 465#define LINK_PROTOCOL 7 466#define CONN_MANAGER 8 467#define ROUTE_DISTRIBUTOR 9 /* obsoleted */ 468#define CHANGEOVER_PROTOCOL 10 469#define NAME_DISTRIBUTOR 11 470#define MSG_FRAGMENTER 12 471#define LINK_CONFIG 13 472#define SOCK_WAKEUP 14 /* pseudo user */ 473 474/* 475 * Connection management protocol message types 476 */ 477#define CONN_PROBE 0 478#define CONN_PROBE_REPLY 1 479#define CONN_ACK 2 480 481/* 482 * Name distributor message types 483 */ 484#define PUBLICATION 0 485#define WITHDRAWAL 1 486 487/* 488 * Segmentation message types 489 */ 490#define FIRST_FRAGMENT 0 491#define FRAGMENT 1 492#define LAST_FRAGMENT 2 493 494/* 495 * Link management protocol message types 496 */ 497#define STATE_MSG 0 498#define RESET_MSG 1 499#define ACTIVATE_MSG 2 500 501/* 502 * Changeover tunnel message types 503 */ 504#define DUPLICATE_MSG 0 505#define ORIGINAL_MSG 1 506 507/* 508 * Config protocol message types 509 */ 510#define DSC_REQ_MSG 0 511#define DSC_RESP_MSG 1 512 513 514/* 515 * Word 1 516 */ 517static inline u32 msg_seq_gap(struct tipc_msg *m) 518{ 519 return msg_bits(m, 1, 16, 0x1fff); 520} 521 522static inline void msg_set_seq_gap(struct tipc_msg *m, u32 n) 523{ 524 msg_set_bits(m, 1, 16, 0x1fff, n); 525} 526 527static inline u32 msg_node_sig(struct tipc_msg *m) 528{ 529 return msg_bits(m, 1, 0, 0xffff); 530} 531 532static inline void msg_set_node_sig(struct tipc_msg *m, u32 n) 533{ 534 msg_set_bits(m, 1, 0, 0xffff, n); 535} 536 537 538/* 539 * Word 2 540 */ 541static inline u32 msg_dest_domain(struct tipc_msg *m) 542{ 543 return msg_word(m, 2); 544} 545 546static inline void msg_set_dest_domain(struct tipc_msg *m, u32 n) 547{ 548 msg_set_word(m, 2, n); 549} 550 551static inline u32 msg_bcgap_after(struct tipc_msg *m) 552{ 553 return msg_bits(m, 2, 16, 0xffff); 554} 555 556static inline void msg_set_bcgap_after(struct tipc_msg *m, u32 n) 557{ 558 msg_set_bits(m, 2, 16, 0xffff, n); 559} 560 561static inline u32 msg_bcgap_to(struct tipc_msg *m) 562{ 563 return msg_bits(m, 2, 0, 0xffff); 564} 565 566static inline void msg_set_bcgap_to(struct tipc_msg *m, u32 n) 567{ 568 msg_set_bits(m, 2, 0, 0xffff, n); 569} 570 571 572/* 573 * Word 4 574 */ 575static inline u32 msg_last_bcast(struct tipc_msg *m) 576{ 577 return msg_bits(m, 4, 16, 0xffff); 578} 579 580static inline void msg_set_last_bcast(struct tipc_msg *m, u32 n) 581{ 582 msg_set_bits(m, 4, 16, 0xffff, n); 583} 584 585static inline void msg_set_fragm_no(struct tipc_msg *m, u32 n) 586{ 587 msg_set_bits(m, 4, 16, 0xffff, n); 588} 589 590 591static inline u32 msg_next_sent(struct tipc_msg *m) 592{ 593 return msg_bits(m, 4, 0, 0xffff); 594} 595 596static inline void msg_set_next_sent(struct tipc_msg *m, u32 n) 597{ 598 msg_set_bits(m, 4, 0, 0xffff, n); 599} 600 601static inline void msg_set_long_msgno(struct tipc_msg *m, u32 n) 602{ 603 msg_set_bits(m, 4, 0, 0xffff, n); 604} 605 606static inline u32 msg_bc_netid(struct tipc_msg *m) 607{ 608 return msg_word(m, 4); 609} 610 611static inline void msg_set_bc_netid(struct tipc_msg *m, u32 id) 612{ 613 msg_set_word(m, 4, id); 614} 615 616static inline u32 msg_link_selector(struct tipc_msg *m) 617{ 618 return msg_bits(m, 4, 0, 1); 619} 620 621static inline void msg_set_link_selector(struct tipc_msg *m, u32 n) 622{ 623 msg_set_bits(m, 4, 0, 1, n); 624} 625 626/* 627 * Word 5 628 */ 629static inline u32 msg_session(struct tipc_msg *m) 630{ 631 return msg_bits(m, 5, 16, 0xffff); 632} 633 634static inline void msg_set_session(struct tipc_msg *m, u32 n) 635{ 636 msg_set_bits(m, 5, 16, 0xffff, n); 637} 638 639static inline u32 msg_probe(struct tipc_msg *m) 640{ 641 return msg_bits(m, 5, 0, 1); 642} 643 644static inline void msg_set_probe(struct tipc_msg *m, u32 val) 645{ 646 msg_set_bits(m, 5, 0, 1, val); 647} 648 649static inline char msg_net_plane(struct tipc_msg *m) 650{ 651 return msg_bits(m, 5, 1, 7) + 'A'; 652} 653 654static inline void msg_set_net_plane(struct tipc_msg *m, char n) 655{ 656 msg_set_bits(m, 5, 1, 7, (n - 'A')); 657} 658 659static inline u32 msg_linkprio(struct tipc_msg *m) 660{ 661 return msg_bits(m, 5, 4, 0x1f); 662} 663 664static inline void msg_set_linkprio(struct tipc_msg *m, u32 n) 665{ 666 msg_set_bits(m, 5, 4, 0x1f, n); 667} 668 669static inline u32 msg_bearer_id(struct tipc_msg *m) 670{ 671 return msg_bits(m, 5, 9, 0x7); 672} 673 674static inline void msg_set_bearer_id(struct tipc_msg *m, u32 n) 675{ 676 msg_set_bits(m, 5, 9, 0x7, n); 677} 678 679static inline u32 msg_redundant_link(struct tipc_msg *m) 680{ 681 return msg_bits(m, 5, 12, 0x1); 682} 683 684static inline void msg_set_redundant_link(struct tipc_msg *m, u32 r) 685{ 686 msg_set_bits(m, 5, 12, 0x1, r); 687} 688 689static inline char *msg_media_addr(struct tipc_msg *m) 690{ 691 return (char *)&m->hdr[TIPC_MEDIA_ADDR_OFFSET]; 692} 693 694/* 695 * Word 9 696 */ 697static inline u32 msg_msgcnt(struct tipc_msg *m) 698{ 699 return msg_bits(m, 9, 16, 0xffff); 700} 701 702static inline void msg_set_msgcnt(struct tipc_msg *m, u32 n) 703{ 704 msg_set_bits(m, 9, 16, 0xffff, n); 705} 706 707static inline u32 msg_bcast_tag(struct tipc_msg *m) 708{ 709 return msg_bits(m, 9, 16, 0xffff); 710} 711 712static inline void msg_set_bcast_tag(struct tipc_msg *m, u32 n) 713{ 714 msg_set_bits(m, 9, 16, 0xffff, n); 715} 716 717static inline u32 msg_max_pkt(struct tipc_msg *m) 718{ 719 return msg_bits(m, 9, 16, 0xffff) * 4; 720} 721 722static inline void msg_set_max_pkt(struct tipc_msg *m, u32 n) 723{ 724 msg_set_bits(m, 9, 16, 0xffff, (n / 4)); 725} 726 727static inline u32 msg_link_tolerance(struct tipc_msg *m) 728{ 729 return msg_bits(m, 9, 0, 0xffff); 730} 731 732static inline void msg_set_link_tolerance(struct tipc_msg *m, u32 n) 733{ 734 msg_set_bits(m, 9, 0, 0xffff, n); 735} 736 737static inline u32 tipc_msg_tot_importance(struct tipc_msg *m) 738{ 739 if ((msg_user(m) == MSG_FRAGMENTER) && (msg_type(m) == FIRST_FRAGMENT)) 740 return msg_importance(msg_get_wrapped(m)); 741 return msg_importance(m); 742} 743 744static inline u32 msg_tot_origport(struct tipc_msg *m) 745{ 746 if ((msg_user(m) == MSG_FRAGMENTER) && (msg_type(m) == FIRST_FRAGMENT)) 747 return msg_origport(msg_get_wrapped(m)); 748 return msg_origport(m); 749} 750 751struct sk_buff *tipc_buf_acquire(u32 size); 752bool tipc_msg_reverse(u32 own_addr, struct sk_buff *buf, u32 *dnode, 753 int err); 754void tipc_msg_init(u32 own_addr, struct tipc_msg *m, u32 user, u32 type, 755 u32 hsize, u32 destnode); 756struct sk_buff *tipc_msg_create(uint user, uint type, uint hdr_sz, 757 uint data_sz, u32 dnode, u32 onode, 758 u32 dport, u32 oport, int errcode); 759int tipc_buf_append(struct sk_buff **headbuf, struct sk_buff **buf); 760bool tipc_msg_bundle(struct sk_buff_head *list, struct sk_buff *skb, u32 mtu); 761bool tipc_msg_make_bundle(struct sk_buff_head *list, 762 struct sk_buff *skb, u32 mtu, u32 dnode); 763bool tipc_msg_extract(struct sk_buff *skb, struct sk_buff **iskb, int *pos); 764int tipc_msg_build(struct tipc_msg *mhdr, struct msghdr *m, 765 int offset, int dsz, int mtu, struct sk_buff_head *list); 766bool tipc_msg_lookup_dest(struct net *net, struct sk_buff *skb, u32 *dnode, 767 int *err); 768struct sk_buff *tipc_msg_reassemble(struct sk_buff_head *list); 769 770/* tipc_skb_peek(): peek and reserve first buffer in list 771 * @list: list to be peeked in 772 * Returns pointer to first buffer in list, if any 773 */ 774static inline struct sk_buff *tipc_skb_peek(struct sk_buff_head *list, 775 spinlock_t *lock) 776{ 777 struct sk_buff *skb; 778 779 spin_lock_bh(lock); 780 skb = skb_peek(list); 781 if (skb) 782 skb_get(skb); 783 spin_unlock_bh(lock); 784 return skb; 785} 786 787/* tipc_skb_peek_port(): find a destination port, ignoring all destinations 788 * up to and including 'filter'. 789 * Note: ignoring previously tried destinations minimizes the risk of 790 * contention on the socket lock 791 * @list: list to be peeked in 792 * @filter: last destination to be ignored from search 793 * Returns a destination port number, of applicable. 794 */ 795static inline u32 tipc_skb_peek_port(struct sk_buff_head *list, u32 filter) 796{ 797 struct sk_buff *skb; 798 u32 dport = 0; 799 bool ignore = true; 800 801 spin_lock_bh(&list->lock); 802 skb_queue_walk(list, skb) { 803 dport = msg_destport(buf_msg(skb)); 804 if (!filter || skb_queue_is_last(list, skb)) 805 break; 806 if (dport == filter) 807 ignore = false; 808 else if (!ignore) 809 break; 810 } 811 spin_unlock_bh(&list->lock); 812 return dport; 813} 814 815/* tipc_skb_dequeue(): unlink first buffer with dest 'dport' from list 816 * @list: list to be unlinked from 817 * @dport: selection criteria for buffer to unlink 818 */ 819static inline struct sk_buff *tipc_skb_dequeue(struct sk_buff_head *list, 820 u32 dport) 821{ 822 struct sk_buff *_skb, *tmp, *skb = NULL; 823 824 spin_lock_bh(&list->lock); 825 skb_queue_walk_safe(list, _skb, tmp) { 826 if (msg_destport(buf_msg(_skb)) == dport) { 827 __skb_unlink(_skb, list); 828 skb = _skb; 829 break; 830 } 831 } 832 spin_unlock_bh(&list->lock); 833 return skb; 834} 835 836/* tipc_skb_queue_tail(): add buffer to tail of list; 837 * @list: list to be appended to 838 * @skb: buffer to append. Always appended 839 * @dport: the destination port of the buffer 840 * returns true if dport differs from previous destination 841 */ 842static inline bool tipc_skb_queue_tail(struct sk_buff_head *list, 843 struct sk_buff *skb, u32 dport) 844{ 845 struct sk_buff *_skb = NULL; 846 bool rv = false; 847 848 spin_lock_bh(&list->lock); 849 _skb = skb_peek_tail(list); 850 if (!_skb || (msg_destport(buf_msg(_skb)) != dport) || 851 (skb_queue_len(list) > 32)) 852 rv = true; 853 __skb_queue_tail(list, skb); 854 spin_unlock_bh(&list->lock); 855 return rv; 856} 857 858#endif