1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 #ifndef _SYS_QUEUE_H_ 33 #define _SYS_QUEUE_H_ 34 35 #include <sys/cdefs.h> 36 37 /* 38 * This file defines four types of data structures: singly-linked lists, 39 * singly-linked tail queues, lists and tail queues. 40 * 41 * A singly-linked list is headed by a single forward pointer. The elements 42 * are singly linked for minimum space and pointer manipulation overhead at 43 * the expense of O(n) removal for arbitrary elements. New elements can be 44 * added to the list after an existing element or at the head of the list. 45 * Elements being removed from the head of the list should use the explicit 46 * macro for this purpose for optimum efficiency. A singly-linked list may 47 * only be traversed in the forward direction. Singly-linked lists are ideal 48 * for applications with large datasets and few or no removals or for 49 * implementing a LIFO queue. 50 * 51 * A singly-linked tail queue is headed by a pair of pointers, one to the 52 * head of the list and the other to the tail of the list. The elements are 53 * singly linked for minimum space and pointer manipulation overhead at the 54 * expense of O(n) removal for arbitrary elements. New elements can be added 55 * to the list after an existing element, at the head of the list, or at the 56 * end of the list. Elements being removed from the head of the tail queue 57 * should use the explicit macro for this purpose for optimum efficiency. 58 * A singly-linked tail queue may only be traversed in the forward direction. 59 * Singly-linked tail queues are ideal for applications with large datasets 60 * and few or no removals or for implementing a FIFO queue. 61 * 62 * A list is headed by a single forward pointer (or an array of forward 63 * pointers for a hash table header). The elements are doubly linked 64 * so that an arbitrary element can be removed without a need to 65 * traverse the list. New elements can be added to the list before 66 * or after an existing element or at the head of the list. A list 67 * may be traversed in either direction. 68 * 69 * A tail queue is headed by a pair of pointers, one to the head of the 70 * list and the other to the tail of the list. The elements are doubly 71 * linked so that an arbitrary element can be removed without a need to 72 * traverse the list. New elements can be added to the list before or 73 * after an existing element, at the head of the list, or at the end of 74 * the list. A tail queue may be traversed in either direction. 75 * 76 * For details on the use of these macros, see the queue(3) manual page. 77 * 78 * Below is a summary of implemented functions where: 79 * + means the macro is available 80 * - means the macro is not available 81 * s means the macro is available but is slow (runs in O(n) time) 82 * 83 * SLIST LIST STAILQ TAILQ 84 * _HEAD + + + + 85 * _CLASS_HEAD + + + + 86 * _HEAD_INITIALIZER + + + + 87 * _ENTRY + + + + 88 * _CLASS_ENTRY + + + + 89 * _INIT + + + + 90 * _EMPTY + + + + 91 * _END + + + + 92 * _FIRST + + + + 93 * _NEXT + + + + 94 * _PREV - + - + 95 * _LAST - - + + 96 * _LAST_FAST - - - + 97 * _FOREACH + + + + 98 * _FOREACH_FROM + + + + 99 * _FOREACH_SAFE + + + + 100 * _FOREACH_FROM_SAFE + + + + 101 * _FOREACH_REVERSE - - - + 102 * _FOREACH_REVERSE_FROM - - - + 103 * _FOREACH_REVERSE_SAFE - - - + 104 * _FOREACH_REVERSE_FROM_SAFE - - - + 105 * _INSERT_HEAD + + + + 106 * _INSERT_BEFORE - + - + 107 * _INSERT_AFTER + + + + 108 * _INSERT_TAIL - - + + 109 * _CONCAT s s + + 110 * _REMOVE_AFTER + - + - 111 * _REMOVE_HEAD + + + + 112 * _REMOVE s + s + 113 * _REPLACE - + - + 114 * _SWAP + + + + 115 * 116 */ 117 #ifdef QUEUE_MACRO_DEBUG 118 #warn Use QUEUE_MACRO_DEBUG_TRACE and/or QUEUE_MACRO_DEBUG_TRASH 119 #define QUEUE_MACRO_DEBUG_TRACE 120 #define QUEUE_MACRO_DEBUG_TRASH 121 #endif 122 123 #ifdef QUEUE_MACRO_DEBUG_TRACE 124 /* Store the last 2 places the queue element or head was altered */ 125 struct qm_trace { 126 unsigned long lastline; 127 unsigned long prevline; 128 const char *lastfile; 129 const char *prevfile; 130 }; 131 132 #define TRACEBUF struct qm_trace trace; 133 #define TRACEBUF_INITIALIZER { __LINE__, 0, __FILE__, NULL } , 134 135 #define QMD_TRACE_HEAD(head) do { \ 136 (head)->trace.prevline = (head)->trace.lastline; \ 137 (head)->trace.prevfile = (head)->trace.lastfile; \ 138 (head)->trace.lastline = __LINE__; \ 139 (head)->trace.lastfile = __FILE__; \ 140 } while (0) 141 142 #define QMD_TRACE_ELEM(elem) do { \ 143 (elem)->trace.prevline = (elem)->trace.lastline; \ 144 (elem)->trace.prevfile = (elem)->trace.lastfile; \ 145 (elem)->trace.lastline = __LINE__; \ 146 (elem)->trace.lastfile = __FILE__; \ 147 } while (0) 148 149 #else /* !QUEUE_MACRO_DEBUG_TRACE */ 150 #define QMD_TRACE_ELEM(elem) 151 #define QMD_TRACE_HEAD(head) 152 #define TRACEBUF 153 #define TRACEBUF_INITIALIZER 154 #endif /* QUEUE_MACRO_DEBUG_TRACE */ 155 156 #ifdef QUEUE_MACRO_DEBUG_TRASH 157 #define QMD_SAVELINK(name, link) void **name = (void *)&(link) 158 #define TRASHIT(x) do {(x) = (void *)-1;} while (0) 159 #define QMD_IS_TRASHED(x) ((x) == (void *)(intptr_t)-1) 160 #else /* !QUEUE_MACRO_DEBUG_TRASH */ 161 #define QMD_SAVELINK(name, link) 162 #define TRASHIT(x) 163 #define QMD_IS_TRASHED(x) 0 164 #endif /* QUEUE_MACRO_DEBUG_TRASH */ 165 166 #ifdef __cplusplus 167 /* 168 * In C++ there can be structure lists and class lists: 169 */ 170 #define QUEUE_TYPEOF(type) type 171 #else 172 #define QUEUE_TYPEOF(type) struct type 173 #endif 174 175 /* 176 * Singly-linked List declarations. 177 */ 178 #define SLIST_HEAD(name, type) \ 179 struct name { \ 180 struct type *slh_first; /* first element */ \ 181 } 182 183 #define SLIST_CLASS_HEAD(name, type) \ 184 struct name { \ 185 class type *slh_first; /* first element */ \ 186 } 187 188 #define SLIST_HEAD_INITIALIZER(head) \ 189 { NULL } 190 191 #define SLIST_ENTRY(type) \ 192 struct { \ 193 struct type *sle_next; /* next element */ \ 194 } 195 196 #define SLIST_CLASS_ENTRY(type) \ 197 struct { \ 198 class type *sle_next; /* next element */ \ 199 } 200 201 /* 202 * Singly-linked List functions. 203 */ 204 #if (defined(_KERNEL) && defined(INVARIANTS)) 205 #define QMD_SLIST_CHECK_PREVPTR(prevp, elm) do { \ 206 if (*(prevp) != (elm)) \ 207 panic("Bad prevptr *(%p) == %p != %p", \ 208 (prevp), *(prevp), (elm)); \ 209 } while (0) 210 #else 211 #define QMD_SLIST_CHECK_PREVPTR(prevp, elm) 212 #endif 213 214 #define SLIST_CONCAT(head1, head2, type, field) do { \ 215 QUEUE_TYPEOF(type) *curelm = SLIST_FIRST(head1); \ 216 if (curelm == NULL) { \ 217 if ((SLIST_FIRST(head1) = SLIST_FIRST(head2)) != NULL) \ 218 SLIST_INIT(head2); \ 219 } else if (SLIST_FIRST(head2) != NULL) { \ 220 while (SLIST_NEXT(curelm, field) != NULL) \ 221 curelm = SLIST_NEXT(curelm, field); \ 222 SLIST_NEXT(curelm, field) = SLIST_FIRST(head2); \ 223 SLIST_INIT(head2); \ 224 } \ 225 } while (0) 226 227 #define SLIST_EMPTY(head) ((head)->slh_first == NULL) 228 229 #define SLIST_FIRST(head) ((head)->slh_first) 230 231 #define SLIST_FOREACH(var, head, field) \ 232 for ((var) = SLIST_FIRST((head)); \ 233 (var); \ 234 (var) = SLIST_NEXT((var), field)) 235 236 #define SLIST_FOREACH_FROM(var, head, field) \ 237 for ((var) = ((var) ? (var) : SLIST_FIRST((head))); \ 238 (var); \ 239 (var) = SLIST_NEXT((var), field)) 240 241 #define SLIST_FOREACH_SAFE(var, head, field, tvar) \ 242 for ((var) = SLIST_FIRST((head)); \ 243 (var) && ((tvar) = SLIST_NEXT((var), field), 1); \ 244 (var) = (tvar)) 245 246 #define SLIST_FOREACH_FROM_SAFE(var, head, field, tvar) \ 247 for ((var) = ((var) ? (var) : SLIST_FIRST((head))); \ 248 (var) && ((tvar) = SLIST_NEXT((var), field), 1); \ 249 (var) = (tvar)) 250 251 #define SLIST_FOREACH_PREVPTR(var, varp, head, field) \ 252 for ((varp) = &SLIST_FIRST((head)); \ 253 ((var) = *(varp)) != NULL; \ 254 (varp) = &SLIST_NEXT((var), field)) 255 256 #define SLIST_INIT(head) do { \ 257 SLIST_FIRST((head)) = NULL; \ 258 } while (0) 259 260 #define SLIST_INSERT_AFTER(slistelm, elm, field) do { \ 261 SLIST_NEXT((elm), field) = SLIST_NEXT((slistelm), field); \ 262 SLIST_NEXT((slistelm), field) = (elm); \ 263 } while (0) 264 265 #define SLIST_INSERT_HEAD(head, elm, field) do { \ 266 SLIST_NEXT((elm), field) = SLIST_FIRST((head)); \ 267 SLIST_FIRST((head)) = (elm); \ 268 } while (0) 269 270 #define SLIST_NEXT(elm, field) ((elm)->field.sle_next) 271 272 #define SLIST_REMOVE(head, elm, type, field) do { \ 273 if (SLIST_FIRST((head)) == (elm)) { \ 274 SLIST_REMOVE_HEAD((head), field); \ 275 } \ 276 else { \ 277 QUEUE_TYPEOF(type) *curelm = SLIST_FIRST(head); \ 278 while (SLIST_NEXT(curelm, field) != (elm)) \ 279 curelm = SLIST_NEXT(curelm, field); \ 280 SLIST_REMOVE_AFTER(curelm, field); \ 281 } \ 282 } while (0) 283 284 #define SLIST_REMOVE_AFTER(elm, field) do { \ 285 QMD_SAVELINK(oldnext, SLIST_NEXT(elm, field)->field.sle_next); \ 286 SLIST_NEXT(elm, field) = \ 287 SLIST_NEXT(SLIST_NEXT(elm, field), field); \ 288 TRASHIT(*oldnext); \ 289 } while (0) 290 291 #define SLIST_REMOVE_HEAD(head, field) do { \ 292 QMD_SAVELINK(oldnext, SLIST_FIRST(head)->field.sle_next); \ 293 SLIST_FIRST((head)) = SLIST_NEXT(SLIST_FIRST((head)), field); \ 294 TRASHIT(*oldnext); \ 295 } while (0) 296 297 #define SLIST_REMOVE_PREVPTR(prevp, elm, field) do { \ 298 QMD_SLIST_CHECK_PREVPTR(prevp, elm); \ 299 *(prevp) = SLIST_NEXT(elm, field); \ 300 TRASHIT((elm)->field.sle_next); \ 301 } while (0) 302 303 #define SLIST_SWAP(head1, head2, type) do { \ 304 QUEUE_TYPEOF(type) *swap_first = SLIST_FIRST(head1); \ 305 SLIST_FIRST(head1) = SLIST_FIRST(head2); \ 306 SLIST_FIRST(head2) = swap_first; \ 307 } while (0) 308 309 #define SLIST_END(head) NULL 310 311 /* 312 * Singly-linked Tail queue declarations. 313 */ 314 #define STAILQ_HEAD(name, type) \ 315 struct name { \ 316 struct type *stqh_first;/* first element */ \ 317 struct type **stqh_last;/* addr of last next element */ \ 318 } 319 320 #define STAILQ_CLASS_HEAD(name, type) \ 321 struct name { \ 322 class type *stqh_first; /* first element */ \ 323 class type **stqh_last; /* addr of last next element */ \ 324 } 325 326 #define STAILQ_HEAD_INITIALIZER(head) \ 327 { NULL, &(head).stqh_first } 328 329 #define STAILQ_ENTRY(type) \ 330 struct { \ 331 struct type *stqe_next; /* next element */ \ 332 } 333 334 #define STAILQ_CLASS_ENTRY(type) \ 335 struct { \ 336 class type *stqe_next; /* next element */ \ 337 } 338 339 /* 340 * Singly-linked Tail queue functions. 341 */ 342 #if (defined(_KERNEL) && defined(INVARIANTS)) 343 /* 344 * QMD_STAILQ_CHECK_EMPTY(STAILQ_HEAD *head) 345 * 346 * Validates that the stailq head's pointer to the last element's next pointer 347 * actually points to the head's first element pointer field. 348 */ 349 #define QMD_STAILQ_CHECK_EMPTY(head) do { \ 350 if ((head)->stqh_last != &(head)->stqh_first) \ 351 panic("Empty stailq %p->stqh_last is %p, not head's " \ 352 "first field address", (head), (head)->stqh_last); \ 353 } while (0) 354 355 #define STAILQ_ASSERT_EMPTY(head) do { \ 356 if (!STAILQ_EMPTY((head))) \ 357 panic("stailq %p is not empty", (head)); \ 358 } 359 360 /* 361 * QMD_STAILQ_CHECK_TAIL(STAILQ_HEAD *head) 362 * 363 * Validates that the stailq's last element's next pointer is NULL. 364 */ 365 #define QMD_STAILQ_CHECK_TAIL(head) do { \ 366 if (*(head)->stqh_last != NULL) \ 367 panic("Stailq %p last element's next pointer is %p, " \ 368 "not NULL", (head), *(head)->stqh_last); \ 369 } while (0) 370 #else 371 #define QMD_STAILQ_CHECK_EMPTY(head) 372 #define STAILQ_ASSERT_EMPTY(head) 373 #define QMD_STAILQ_CHECK_TAIL(head) 374 #endif /* (_KERNEL && INVARIANTS) */ 375 376 #define STAILQ_CONCAT(head1, head2) do { \ 377 if (!STAILQ_EMPTY((head2))) { \ 378 *(head1)->stqh_last = (head2)->stqh_first; \ 379 (head1)->stqh_last = (head2)->stqh_last; \ 380 STAILQ_INIT((head2)); \ 381 } \ 382 } while (0) 383 384 #define STAILQ_EMPTY(head) ({ \ 385 if (STAILQ_FIRST(head) == NULL) \ 386 QMD_STAILQ_CHECK_EMPTY(head); \ 387 STAILQ_FIRST(head) == NULL; \ 388 }) 389 390 #define STAILQ_FIRST(head) ((head)->stqh_first) 391 392 #define STAILQ_FOREACH(var, head, field) \ 393 for((var) = STAILQ_FIRST((head)); \ 394 (var); \ 395 (var) = STAILQ_NEXT((var), field)) 396 397 #define STAILQ_FOREACH_FROM(var, head, field) \ 398 for ((var) = ((var) ? (var) : STAILQ_FIRST((head))); \ 399 (var); \ 400 (var) = STAILQ_NEXT((var), field)) 401 402 #define STAILQ_FOREACH_SAFE(var, head, field, tvar) \ 403 for ((var) = STAILQ_FIRST((head)); \ 404 (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ 405 (var) = (tvar)) 406 407 #define STAILQ_FOREACH_FROM_SAFE(var, head, field, tvar) \ 408 for ((var) = ((var) ? (var) : STAILQ_FIRST((head))); \ 409 (var) && ((tvar) = STAILQ_NEXT((var), field), 1); \ 410 (var) = (tvar)) 411 412 #define STAILQ_INIT(head) do { \ 413 STAILQ_FIRST((head)) = NULL; \ 414 (head)->stqh_last = &STAILQ_FIRST((head)); \ 415 } while (0) 416 417 #define STAILQ_INSERT_AFTER(head, tqelm, elm, field) do { \ 418 if ((STAILQ_NEXT((elm), field) = STAILQ_NEXT((tqelm), field)) == NULL)\ 419 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 420 STAILQ_NEXT((tqelm), field) = (elm); \ 421 } while (0) 422 423 #define STAILQ_INSERT_HEAD(head, elm, field) do { \ 424 if ((STAILQ_NEXT((elm), field) = STAILQ_FIRST((head))) == NULL) \ 425 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 426 STAILQ_FIRST((head)) = (elm); \ 427 } while (0) 428 429 #define STAILQ_INSERT_TAIL(head, elm, field) do { \ 430 QMD_STAILQ_CHECK_TAIL(head); \ 431 STAILQ_NEXT((elm), field) = NULL; \ 432 *(head)->stqh_last = (elm); \ 433 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 434 } while (0) 435 436 #define STAILQ_LAST(head, type, field) \ 437 (STAILQ_EMPTY((head)) ? NULL : \ 438 __containerof((head)->stqh_last, \ 439 QUEUE_TYPEOF(type), field.stqe_next)) 440 441 #define STAILQ_NEXT(elm, field) ((elm)->field.stqe_next) 442 443 #define STAILQ_REMOVE(head, elm, type, field) do { \ 444 QMD_SAVELINK(oldnext, (elm)->field.stqe_next); \ 445 if (STAILQ_FIRST((head)) == (elm)) { \ 446 STAILQ_REMOVE_HEAD((head), field); \ 447 } \ 448 else { \ 449 QUEUE_TYPEOF(type) *curelm = STAILQ_FIRST(head); \ 450 while (STAILQ_NEXT(curelm, field) != (elm)) \ 451 curelm = STAILQ_NEXT(curelm, field); \ 452 STAILQ_REMOVE_AFTER(head, curelm, field); \ 453 } \ 454 TRASHIT(*oldnext); \ 455 } while (0) 456 457 #define STAILQ_REMOVE_AFTER(head, elm, field) do { \ 458 if ((STAILQ_NEXT(elm, field) = \ 459 STAILQ_NEXT(STAILQ_NEXT(elm, field), field)) == NULL) \ 460 (head)->stqh_last = &STAILQ_NEXT((elm), field); \ 461 } while (0) 462 463 #define STAILQ_REMOVE_HEAD(head, field) do { \ 464 if ((STAILQ_FIRST((head)) = \ 465 STAILQ_NEXT(STAILQ_FIRST((head)), field)) == NULL) \ 466 (head)->stqh_last = &STAILQ_FIRST((head)); \ 467 } while (0) 468 469 #define STAILQ_SWAP(head1, head2, type) do { \ 470 QUEUE_TYPEOF(type) *swap_first = STAILQ_FIRST(head1); \ 471 QUEUE_TYPEOF(type) **swap_last = (head1)->stqh_last; \ 472 STAILQ_FIRST(head1) = STAILQ_FIRST(head2); \ 473 (head1)->stqh_last = (head2)->stqh_last; \ 474 STAILQ_FIRST(head2) = swap_first; \ 475 (head2)->stqh_last = swap_last; \ 476 if (STAILQ_FIRST(head1) == NULL) \ 477 (head1)->stqh_last = &STAILQ_FIRST(head1); \ 478 if (STAILQ_FIRST(head2) == NULL) \ 479 (head2)->stqh_last = &STAILQ_FIRST(head2); \ 480 } while (0) 481 482 #define STAILQ_END(head) NULL 483 484 485 /* 486 * List declarations. 487 */ 488 #define LIST_HEAD(name, type) \ 489 struct name { \ 490 struct type *lh_first; /* first element */ \ 491 } 492 493 #define LIST_CLASS_HEAD(name, type) \ 494 struct name { \ 495 class type *lh_first; /* first element */ \ 496 } 497 498 #define LIST_HEAD_INITIALIZER(head) \ 499 { NULL } 500 501 #define LIST_ENTRY(type) \ 502 struct { \ 503 struct type *le_next; /* next element */ \ 504 struct type **le_prev; /* address of previous next element */ \ 505 } 506 507 #define LIST_CLASS_ENTRY(type) \ 508 struct { \ 509 class type *le_next; /* next element */ \ 510 class type **le_prev; /* address of previous next element */ \ 511 } 512 513 /* 514 * List functions. 515 */ 516 517 #if (defined(_KERNEL) && defined(INVARIANTS)) 518 /* 519 * QMD_LIST_CHECK_HEAD(LIST_HEAD *head, LIST_ENTRY NAME) 520 * 521 * If the list is non-empty, validates that the first element of the list 522 * points back at 'head.' 523 */ 524 #define QMD_LIST_CHECK_HEAD(head, field) do { \ 525 if (LIST_FIRST((head)) != NULL && \ 526 LIST_FIRST((head))->field.le_prev != \ 527 &LIST_FIRST((head))) \ 528 panic("Bad list head %p first->prev != head", (head)); \ 529 } while (0) 530 531 /* 532 * QMD_LIST_CHECK_NEXT(TYPE *elm, LIST_ENTRY NAME) 533 * 534 * If an element follows 'elm' in the list, validates that the next element 535 * points back at 'elm.' 536 */ 537 #define QMD_LIST_CHECK_NEXT(elm, field) do { \ 538 if (LIST_NEXT((elm), field) != NULL && \ 539 LIST_NEXT((elm), field)->field.le_prev != \ 540 &((elm)->field.le_next)) \ 541 panic("Bad link elm %p next->prev != elm", (elm)); \ 542 } while (0) 543 544 /* 545 * QMD_LIST_CHECK_PREV(TYPE *elm, LIST_ENTRY NAME) 546 * 547 * Validates that the previous element (or head of the list) points to 'elm.' 548 */ 549 #define QMD_LIST_CHECK_PREV(elm, field) do { \ 550 if (*(elm)->field.le_prev != (elm)) \ 551 panic("Bad link elm %p prev->next != elm", (elm)); \ 552 } while (0) 553 #else 554 #define QMD_LIST_CHECK_HEAD(head, field) 555 #define QMD_LIST_CHECK_NEXT(elm, field) 556 #define QMD_LIST_CHECK_PREV(elm, field) 557 #endif /* (_KERNEL && INVARIANTS) */ 558 559 #define LIST_CONCAT(head1, head2, type, field) do { \ 560 QUEUE_TYPEOF(type) *curelm = LIST_FIRST(head1); \ 561 if (curelm == NULL) { \ 562 if ((LIST_FIRST(head1) = LIST_FIRST(head2)) != NULL) { \ 563 LIST_FIRST(head2)->field.le_prev = \ 564 &LIST_FIRST((head1)); \ 565 LIST_INIT(head2); \ 566 } \ 567 } else if (LIST_FIRST(head2) != NULL) { \ 568 while (LIST_NEXT(curelm, field) != NULL) \ 569 curelm = LIST_NEXT(curelm, field); \ 570 LIST_NEXT(curelm, field) = LIST_FIRST(head2); \ 571 LIST_FIRST(head2)->field.le_prev = &LIST_NEXT(curelm, field);\ 572 LIST_INIT(head2); \ 573 } \ 574 } while (0) 575 576 #define LIST_EMPTY(head) ((head)->lh_first == NULL) 577 578 #define LIST_FIRST(head) ((head)->lh_first) 579 580 #define LIST_FOREACH(var, head, field) \ 581 for ((var) = LIST_FIRST((head)); \ 582 (var); \ 583 (var) = LIST_NEXT((var), field)) 584 585 #define LIST_FOREACH_FROM(var, head, field) \ 586 for ((var) = ((var) ? (var) : LIST_FIRST((head))); \ 587 (var); \ 588 (var) = LIST_NEXT((var), field)) 589 590 #define LIST_FOREACH_SAFE(var, head, field, tvar) \ 591 for ((var) = LIST_FIRST((head)); \ 592 (var) && ((tvar) = LIST_NEXT((var), field), 1); \ 593 (var) = (tvar)) 594 595 #define LIST_FOREACH_FROM_SAFE(var, head, field, tvar) \ 596 for ((var) = ((var) ? (var) : LIST_FIRST((head))); \ 597 (var) && ((tvar) = LIST_NEXT((var), field), 1); \ 598 (var) = (tvar)) 599 600 #define LIST_INIT(head) do { \ 601 LIST_FIRST((head)) = NULL; \ 602 } while (0) 603 604 #define LIST_INSERT_AFTER(listelm, elm, field) do { \ 605 QMD_LIST_CHECK_NEXT(listelm, field); \ 606 if ((LIST_NEXT((elm), field) = LIST_NEXT((listelm), field)) != NULL)\ 607 LIST_NEXT((listelm), field)->field.le_prev = \ 608 &LIST_NEXT((elm), field); \ 609 LIST_NEXT((listelm), field) = (elm); \ 610 (elm)->field.le_prev = &LIST_NEXT((listelm), field); \ 611 } while (0) 612 613 #define LIST_INSERT_BEFORE(listelm, elm, field) do { \ 614 QMD_LIST_CHECK_PREV(listelm, field); \ 615 (elm)->field.le_prev = (listelm)->field.le_prev; \ 616 LIST_NEXT((elm), field) = (listelm); \ 617 *(listelm)->field.le_prev = (elm); \ 618 (listelm)->field.le_prev = &LIST_NEXT((elm), field); \ 619 } while (0) 620 621 #define LIST_INSERT_HEAD(head, elm, field) do { \ 622 QMD_LIST_CHECK_HEAD((head), field); \ 623 if ((LIST_NEXT((elm), field) = LIST_FIRST((head))) != NULL) \ 624 LIST_FIRST((head))->field.le_prev = &LIST_NEXT((elm), field);\ 625 LIST_FIRST((head)) = (elm); \ 626 (elm)->field.le_prev = &LIST_FIRST((head)); \ 627 } while (0) 628 629 #define LIST_NEXT(elm, field) ((elm)->field.le_next) 630 631 #define LIST_PREV(elm, head, type, field) \ 632 ((elm)->field.le_prev == &LIST_FIRST((head)) ? NULL : \ 633 __containerof((elm)->field.le_prev, \ 634 QUEUE_TYPEOF(type), field.le_next)) 635 636 #define LIST_REMOVE_HEAD(head, field) \ 637 LIST_REMOVE(LIST_FIRST(head), field) 638 639 #define LIST_REMOVE(elm, field) do { \ 640 QMD_SAVELINK(oldnext, (elm)->field.le_next); \ 641 QMD_SAVELINK(oldprev, (elm)->field.le_prev); \ 642 QMD_LIST_CHECK_NEXT(elm, field); \ 643 QMD_LIST_CHECK_PREV(elm, field); \ 644 if (LIST_NEXT((elm), field) != NULL) \ 645 LIST_NEXT((elm), field)->field.le_prev = \ 646 (elm)->field.le_prev; \ 647 *(elm)->field.le_prev = LIST_NEXT((elm), field); \ 648 TRASHIT(*oldnext); \ 649 TRASHIT(*oldprev); \ 650 } while (0) 651 652 #define LIST_REPLACE(elm, elm2, field) do { \ 653 QMD_SAVELINK(oldnext, (elm)->field.le_next); \ 654 QMD_SAVELINK(oldprev, (elm)->field.le_prev); \ 655 QMD_LIST_CHECK_NEXT(elm, field); \ 656 QMD_LIST_CHECK_PREV(elm, field); \ 657 LIST_NEXT((elm2), field) = LIST_NEXT((elm), field); \ 658 if (LIST_NEXT((elm2), field) != NULL) \ 659 LIST_NEXT((elm2), field)->field.le_prev = \ 660 &(elm2)->field.le_next; \ 661 (elm2)->field.le_prev = (elm)->field.le_prev; \ 662 *(elm2)->field.le_prev = (elm2); \ 663 TRASHIT(*oldnext); \ 664 TRASHIT(*oldprev); \ 665 } while (0) 666 667 #define LIST_SWAP(head1, head2, type, field) do { \ 668 QUEUE_TYPEOF(type) *swap_tmp = LIST_FIRST(head1); \ 669 LIST_FIRST((head1)) = LIST_FIRST((head2)); \ 670 LIST_FIRST((head2)) = swap_tmp; \ 671 if ((swap_tmp = LIST_FIRST((head1))) != NULL) \ 672 swap_tmp->field.le_prev = &LIST_FIRST((head1)); \ 673 if ((swap_tmp = LIST_FIRST((head2))) != NULL) \ 674 swap_tmp->field.le_prev = &LIST_FIRST((head2)); \ 675 } while (0) 676 677 #define LIST_END(head) NULL 678 679 /* 680 * Tail queue declarations. 681 */ 682 #define TAILQ_HEAD(name, type) \ 683 struct name { \ 684 struct type *tqh_first; /* first element */ \ 685 struct type **tqh_last; /* addr of last next element */ \ 686 TRACEBUF \ 687 } 688 689 #define TAILQ_CLASS_HEAD(name, type) \ 690 struct name { \ 691 class type *tqh_first; /* first element */ \ 692 class type **tqh_last; /* addr of last next element */ \ 693 TRACEBUF \ 694 } 695 696 #define TAILQ_HEAD_INITIALIZER(head) \ 697 { NULL, &(head).tqh_first, TRACEBUF_INITIALIZER } 698 699 #define TAILQ_ENTRY(type) \ 700 struct { \ 701 struct type *tqe_next; /* next element */ \ 702 struct type **tqe_prev; /* address of previous next element */ \ 703 TRACEBUF \ 704 } 705 706 #define TAILQ_CLASS_ENTRY(type) \ 707 struct { \ 708 class type *tqe_next; /* next element */ \ 709 class type **tqe_prev; /* address of previous next element */ \ 710 TRACEBUF \ 711 } 712 713 /* 714 * Tail queue functions. 715 */ 716 #if (defined(_KERNEL) && defined(INVARIANTS)) 717 /* 718 * QMD_TAILQ_CHECK_HEAD(TAILQ_HEAD *head, TAILQ_ENTRY NAME) 719 * 720 * If the tailq is non-empty, validates that the first element of the tailq 721 * points back at 'head.' 722 */ 723 #define QMD_TAILQ_CHECK_HEAD(head, field) do { \ 724 if (!TAILQ_EMPTY(head) && \ 725 TAILQ_FIRST((head))->field.tqe_prev != \ 726 &TAILQ_FIRST((head))) \ 727 panic("Bad tailq head %p first->prev != head", (head)); \ 728 } while (0) 729 730 /* 731 * QMD_TAILQ_CHECK_TAIL(TAILQ_HEAD *head, TAILQ_ENTRY NAME) 732 * 733 * Validates that the tail of the tailq is a pointer to pointer to NULL. 734 */ 735 #define QMD_TAILQ_CHECK_TAIL(head, field) do { \ 736 if (*(head)->tqh_last != NULL) \ 737 panic("Bad tailq NEXT(%p->tqh_last) != NULL", (head)); \ 738 } while (0) 739 740 /* 741 * QMD_TAILQ_CHECK_NEXT(TYPE *elm, TAILQ_ENTRY NAME) 742 * 743 * If an element follows 'elm' in the tailq, validates that the next element 744 * points back at 'elm.' 745 */ 746 #define QMD_TAILQ_CHECK_NEXT(elm, field) do { \ 747 if (TAILQ_NEXT((elm), field) != NULL && \ 748 TAILQ_NEXT((elm), field)->field.tqe_prev != \ 749 &((elm)->field.tqe_next)) \ 750 panic("Bad link elm %p next->prev != elm", (elm)); \ 751 } while (0) 752 753 /* 754 * QMD_TAILQ_CHECK_PREV(TYPE *elm, TAILQ_ENTRY NAME) 755 * 756 * Validates that the previous element (or head of the tailq) points to 'elm.' 757 */ 758 #define QMD_TAILQ_CHECK_PREV(elm, field) do { \ 759 if (*(elm)->field.tqe_prev != (elm)) \ 760 panic("Bad link elm %p prev->next != elm", (elm)); \ 761 } while (0) 762 #else 763 #define QMD_TAILQ_CHECK_HEAD(head, field) 764 #define QMD_TAILQ_CHECK_TAIL(head, headname) 765 #define QMD_TAILQ_CHECK_NEXT(elm, field) 766 #define QMD_TAILQ_CHECK_PREV(elm, field) 767 #endif /* (_KERNEL && INVARIANTS) */ 768 769 #define TAILQ_CONCAT(head1, head2, field) do { \ 770 if (!TAILQ_EMPTY(head2)) { \ 771 *(head1)->tqh_last = (head2)->tqh_first; \ 772 (head2)->tqh_first->field.tqe_prev = (head1)->tqh_last; \ 773 (head1)->tqh_last = (head2)->tqh_last; \ 774 TAILQ_INIT((head2)); \ 775 QMD_TRACE_HEAD(head1); \ 776 QMD_TRACE_HEAD(head2); \ 777 } \ 778 } while (0) 779 780 #define TAILQ_EMPTY(head) ((head)->tqh_first == NULL) 781 782 #define TAILQ_FIRST(head) ((head)->tqh_first) 783 784 #define TAILQ_FOREACH(var, head, field) \ 785 for ((var) = TAILQ_FIRST((head)); \ 786 (var); \ 787 (var) = TAILQ_NEXT((var), field)) 788 789 #define TAILQ_FOREACH_FROM(var, head, field) \ 790 for ((var) = ((var) ? (var) : TAILQ_FIRST((head))); \ 791 (var); \ 792 (var) = TAILQ_NEXT((var), field)) 793 794 #define TAILQ_FOREACH_SAFE(var, head, field, tvar) \ 795 for ((var) = TAILQ_FIRST((head)); \ 796 (var) && ((tvar) = TAILQ_NEXT((var), field), 1); \ 797 (var) = (tvar)) 798 799 #define TAILQ_FOREACH_FROM_SAFE(var, head, field, tvar) \ 800 for ((var) = ((var) ? (var) : TAILQ_FIRST((head))); \ 801 (var) && ((tvar) = TAILQ_NEXT((var), field), 1); \ 802 (var) = (tvar)) 803 804 #define TAILQ_FOREACH_REVERSE(var, head, headname, field) \ 805 for ((var) = TAILQ_LAST((head), headname); \ 806 (var); \ 807 (var) = TAILQ_PREV((var), headname, field)) 808 809 #define TAILQ_FOREACH_REVERSE_FROM(var, head, headname, field) \ 810 for ((var) = ((var) ? (var) : TAILQ_LAST((head), headname)); \ 811 (var); \ 812 (var) = TAILQ_PREV((var), headname, field)) 813 814 #define TAILQ_FOREACH_REVERSE_SAFE(var, head, headname, field, tvar) \ 815 for ((var) = TAILQ_LAST((head), headname); \ 816 (var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \ 817 (var) = (tvar)) 818 819 #define TAILQ_FOREACH_REVERSE_FROM_SAFE(var, head, headname, field, tvar)\ 820 for ((var) = ((var) ? (var) : TAILQ_LAST((head), headname)); \ 821 (var) && ((tvar) = TAILQ_PREV((var), headname, field), 1); \ 822 (var) = (tvar)) 823 824 #define TAILQ_INIT(head) do { \ 825 TAILQ_FIRST((head)) = NULL; \ 826 (head)->tqh_last = &TAILQ_FIRST((head)); \ 827 QMD_TRACE_HEAD(head); \ 828 } while (0) 829 830 #define TAILQ_INSERT_AFTER(head, listelm, elm, field) do { \ 831 QMD_TAILQ_CHECK_NEXT(listelm, field); \ 832 if ((TAILQ_NEXT((elm), field) = TAILQ_NEXT((listelm), field)) != NULL)\ 833 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 834 &TAILQ_NEXT((elm), field); \ 835 else { \ 836 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 837 QMD_TRACE_HEAD(head); \ 838 } \ 839 TAILQ_NEXT((listelm), field) = (elm); \ 840 (elm)->field.tqe_prev = &TAILQ_NEXT((listelm), field); \ 841 QMD_TRACE_ELEM(&(elm)->field); \ 842 QMD_TRACE_ELEM(&(listelm)->field); \ 843 } while (0) 844 845 #define TAILQ_INSERT_BEFORE(listelm, elm, field) do { \ 846 QMD_TAILQ_CHECK_PREV(listelm, field); \ 847 (elm)->field.tqe_prev = (listelm)->field.tqe_prev; \ 848 TAILQ_NEXT((elm), field) = (listelm); \ 849 *(listelm)->field.tqe_prev = (elm); \ 850 (listelm)->field.tqe_prev = &TAILQ_NEXT((elm), field); \ 851 QMD_TRACE_ELEM(&(elm)->field); \ 852 QMD_TRACE_ELEM(&(listelm)->field); \ 853 } while (0) 854 855 #define TAILQ_INSERT_HEAD(head, elm, field) do { \ 856 QMD_TAILQ_CHECK_HEAD(head, field); \ 857 if ((TAILQ_NEXT((elm), field) = TAILQ_FIRST((head))) != NULL) \ 858 TAILQ_FIRST((head))->field.tqe_prev = \ 859 &TAILQ_NEXT((elm), field); \ 860 else \ 861 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 862 TAILQ_FIRST((head)) = (elm); \ 863 (elm)->field.tqe_prev = &TAILQ_FIRST((head)); \ 864 QMD_TRACE_HEAD(head); \ 865 QMD_TRACE_ELEM(&(elm)->field); \ 866 } while (0) 867 868 #define TAILQ_INSERT_TAIL(head, elm, field) do { \ 869 QMD_TAILQ_CHECK_TAIL(head, field); \ 870 TAILQ_NEXT((elm), field) = NULL; \ 871 (elm)->field.tqe_prev = (head)->tqh_last; \ 872 *(head)->tqh_last = (elm); \ 873 (head)->tqh_last = &TAILQ_NEXT((elm), field); \ 874 QMD_TRACE_HEAD(head); \ 875 QMD_TRACE_ELEM(&(elm)->field); \ 876 } while (0) 877 878 #define TAILQ_LAST(head, headname) \ 879 (*(((struct headname *)((head)->tqh_last))->tqh_last)) 880 881 /* 882 * The FAST function is fast in that it causes no data access other 883 * then the access to the head. The standard LAST function above 884 * will cause a data access of both the element you want and 885 * the previous element. FAST is very useful for instances when 886 * you may want to prefetch the last data element. 887 */ 888 #define TAILQ_LAST_FAST(head, type, field) \ 889 (TAILQ_EMPTY(head) ? NULL : __containerof((head)->tqh_last, QUEUE_TYPEOF(type), field.tqe_next)) 890 891 #define TAILQ_NEXT(elm, field) ((elm)->field.tqe_next) 892 893 #define TAILQ_PREV(elm, headname, field) \ 894 (*(((struct headname *)((elm)->field.tqe_prev))->tqh_last)) 895 896 #define TAILQ_PREV_FAST(elm, head, type, field) \ 897 ((elm)->field.tqe_prev == &(head)->tqh_first ? NULL : \ 898 __containerof((elm)->field.tqe_prev, QUEUE_TYPEOF(type), field.tqe_next)) 899 900 #define TAILQ_REMOVE_HEAD(head, field) \ 901 TAILQ_REMOVE(head, TAILQ_FIRST(head), field) 902 903 #define TAILQ_REMOVE(head, elm, field) do { \ 904 QMD_SAVELINK(oldnext, (elm)->field.tqe_next); \ 905 QMD_SAVELINK(oldprev, (elm)->field.tqe_prev); \ 906 QMD_TAILQ_CHECK_NEXT(elm, field); \ 907 QMD_TAILQ_CHECK_PREV(elm, field); \ 908 if ((TAILQ_NEXT((elm), field)) != NULL) \ 909 TAILQ_NEXT((elm), field)->field.tqe_prev = \ 910 (elm)->field.tqe_prev; \ 911 else { \ 912 (head)->tqh_last = (elm)->field.tqe_prev; \ 913 QMD_TRACE_HEAD(head); \ 914 } \ 915 *(elm)->field.tqe_prev = TAILQ_NEXT((elm), field); \ 916 TRASHIT(*oldnext); \ 917 TRASHIT(*oldprev); \ 918 QMD_TRACE_ELEM(&(elm)->field); \ 919 } while (0) 920 921 #define TAILQ_REPLACE(head, elm, elm2, field) do { \ 922 QMD_SAVELINK(oldnext, (elm)->field.tqe_next); \ 923 QMD_SAVELINK(oldprev, (elm)->field.tqe_prev); \ 924 QMD_TAILQ_CHECK_NEXT(elm, field); \ 925 QMD_TAILQ_CHECK_PREV(elm, field); \ 926 TAILQ_NEXT((elm2), field) = TAILQ_NEXT((elm), field); \ 927 if (TAILQ_NEXT((elm2), field) != TAILQ_END(head)) \ 928 TAILQ_NEXT((elm2), field)->field.tqe_prev = \ 929 &(elm2)->field.tqe_next; \ 930 else \ 931 (head)->tqh_last = &(elm2)->field.tqe_next; \ 932 (elm2)->field.tqe_prev = (elm)->field.tqe_prev; \ 933 *(elm2)->field.tqe_prev = (elm2); \ 934 TRASHIT(*oldnext); \ 935 TRASHIT(*oldprev); \ 936 QMD_TRACE_ELEM(&(elm)->field); \ 937 } while (0) 938 939 #define TAILQ_SWAP(head1, head2, type, field) do { \ 940 QUEUE_TYPEOF(type) *swap_first = (head1)->tqh_first; \ 941 QUEUE_TYPEOF(type) **swap_last = (head1)->tqh_last; \ 942 (head1)->tqh_first = (head2)->tqh_first; \ 943 (head1)->tqh_last = (head2)->tqh_last; \ 944 (head2)->tqh_first = swap_first; \ 945 (head2)->tqh_last = swap_last; \ 946 if ((swap_first = (head1)->tqh_first) != NULL) \ 947 swap_first->field.tqe_prev = &(head1)->tqh_first; \ 948 else \ 949 (head1)->tqh_last = &(head1)->tqh_first; \ 950 if ((swap_first = (head2)->tqh_first) != NULL) \ 951 swap_first->field.tqe_prev = &(head2)->tqh_first; \ 952 else \ 953 (head2)->tqh_last = &(head2)->tqh_first; \ 954 } while (0) 955 956 #define TAILQ_END(head) NULL 957 958 #endif /* !_SYS_QUEUE_H_ */ 959