| commit | author | age | ||
| d6b4a7 | 1 | /********************************************************************************* |
| G | 2 | * Copyright: (C) 2020 LingYun IoT System Studio |
| 3 | * All rights reserved. | |
| 4 | * | |
| 5 | * Filename: list.h | |
| 6 | * Description: This file is copied from Linux kernel, which provide link list API. | |
| 7 | * | |
| 8 | * Version: 1.0.0(08/09/2020) | |
| 9 | * Author: Guo Wenxue <guowenxue@gmail.com> | |
| 10 | * ChangeLog: 1, Release initial version on "08/09/2020 02:24:34 AM" | |
| 11 | * | |
| 12 | ********************************************************************************/ | |
| 13 | ||
| 14 | #ifndef _LINUX_LIST_H | |
| 15 | #define _LINUX_LIST_H | |
| 16 | ||
| 17 | #include <linux/stddef.h> | |
| 18 | ||
| 19 | ||
| 20 | /** | |
| 21 | * container_of - cast a member of a structure out to the containing structure | |
| 22 | * @ptr: the pointer to the member. | |
| 23 | * @type: the type of the container struct this is embedded in. | |
| 24 | * @member: the name of the member within the struct. | |
| 25 | * | |
| 26 | */ | |
| 27 | #undef offsetof | |
| 28 | #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) | |
| 29 | #define container_of(ptr, type, member) ({ \ | |
| 30 | const typeof( ((type *)0)->member ) *__mptr = (ptr); \ | |
| 31 | (type *)( (char *)__mptr - offsetof(type,member) );}) | |
| 32 | ||
| 33 | ||
| 34 | /* | |
| 35 | * Architectures might want to move the poison pointer offset | |
| 36 | * into some well-recognized area such as 0xdead000000000000, | |
| 37 | * that is also not mappable by user-space exploits: | |
| 38 | */ | |
| 39 | #ifdef CONFIG_ILLEGAL_POINTER_VALUE | |
| 40 | # define POISON_POINTER_DELTA _AC(CONFIG_ILLEGAL_POINTER_VALUE, UL) | |
| 41 | #else | |
| 42 | # define POISON_POINTER_DELTA 0 | |
| 43 | #endif | |
| 44 | ||
| 45 | /* | |
| 46 | * These are non-NULL pointers that will result in page faults | |
| 47 | * under normal circumstances, used to verify that nobody uses | |
| 48 | * non-initialized list entries. | |
| 49 | */ | |
| 50 | #define LIST_POISON1 ((void *) 0x00100100 + POISON_POINTER_DELTA) | |
| 51 | #define LIST_POISON2 ((void *) 0x00200200 + POISON_POINTER_DELTA) | |
| 52 | ||
| 53 | #ifndef ARCH_HAS_PREFETCH | |
| 54 | #define ARCH_HAS_PREFETCH | |
| 55 | static inline void prefetch(const void *x) {;} | |
| 56 | #endif | |
| 57 | ||
| 58 | /* | |
| 59 | * Simple doubly linked list implementation. | |
| 60 | * | |
| 61 | * Some of the internal functions ("__xxx") are useful when | |
| 62 | * manipulating whole lists rather than single entries, as | |
| 63 | * sometimes we already know the next/prev entries and we can | |
| 64 | * generate better code by using them directly rather than | |
| 65 | * using the generic single-entry routines. | |
| 66 | */ | |
| 67 | ||
| 68 | struct list_head { | |
| 69 | struct list_head *next, *prev; | |
| 70 | }; | |
| 71 | ||
| 72 | #define LIST_HEAD_INIT(name) { &(name), &(name) } | |
| 73 | ||
| 74 | #define LIST_HEAD(name) \ | |
| 75 | struct list_head name = LIST_HEAD_INIT(name) | |
| 76 | ||
| 77 | static inline void INIT_LIST_HEAD(struct list_head *list) | |
| 78 | { | |
| 79 | list->next = list; | |
| 80 | list->prev = list; | |
| 81 | } | |
| 82 | ||
| 83 | /* | |
| 84 | * Insert a new entry between two known consecutive entries. | |
| 85 | * | |
| 86 | * This is only for internal list manipulation where we know | |
| 87 | * the prev/next entries already! | |
| 88 | */ | |
| 89 | static inline void __list_add(struct list_head *new, | |
| 90 | struct list_head *prev, | |
| 91 | struct list_head *next) | |
| 92 | { | |
| 93 | next->prev = new; | |
| 94 | new->next = next; | |
| 95 | new->prev = prev; | |
| 96 | prev->next = new; | |
| 97 | } | |
| 98 | ||
| 99 | /** | |
| 100 | * list_add - add a new entry | |
| 101 | * @new: new entry to be added | |
| 102 | * @head: list head to add it after | |
| 103 | * | |
| 104 | * Insert a new entry after the specified head. | |
| 105 | * This is good for implementing stacks. | |
| 106 | */ | |
| 107 | static inline void list_add(struct list_head *new, struct list_head *head) | |
| 108 | { | |
| 109 | __list_add(new, head, head->next); | |
| 110 | } | |
| 111 | ||
| 112 | /** | |
| 113 | * list_add_tail - add a new entry | |
| 114 | * @new: new entry to be added | |
| 115 | * @head: list head to add it before | |
| 116 | * | |
| 117 | * Insert a new entry before the specified head. | |
| 118 | * This is useful for implementing queues. | |
| 119 | */ | |
| 120 | static inline void list_add_tail(struct list_head *new, struct list_head *head) | |
| 121 | { | |
| 122 | __list_add(new, head->prev, head); | |
| 123 | } | |
| 124 | ||
| 125 | /* | |
| 126 | * Delete a list entry by making the prev/next entries | |
| 127 | * point to each other. | |
| 128 | * | |
| 129 | * This is only for internal list manipulation where we know | |
| 130 | * the prev/next entries already! | |
| 131 | */ | |
| 132 | static inline void __list_del(struct list_head *prev, struct list_head *next) | |
| 133 | { | |
| 134 | next->prev = prev; | |
| 135 | prev->next = next; | |
| 136 | } | |
| 137 | ||
| 138 | /** | |
| 139 | * list_del - deletes entry from list. | |
| 140 | * @entry: the element to delete from the list. | |
| 141 | * Note: list_empty() on entry does not return true after this, the entry is | |
| 142 | * in an undefined state. | |
| 143 | */ | |
| 144 | static inline void list_del(struct list_head *entry) | |
| 145 | { | |
| 146 | __list_del(entry->prev, entry->next); | |
| 147 | entry->next = LIST_POISON1; | |
| 148 | entry->prev = LIST_POISON2; | |
| 149 | } | |
| 150 | ||
| 151 | /** | |
| 152 | * list_replace - replace old entry by new one | |
| 153 | * @old : the element to be replaced | |
| 154 | * @new : the new element to insert | |
| 155 | * | |
| 156 | * If @old was empty, it will be overwritten. | |
| 157 | */ | |
| 158 | static inline void list_replace(struct list_head *old, | |
| 159 | struct list_head *new) | |
| 160 | { | |
| 161 | new->next = old->next; | |
| 162 | new->next->prev = new; | |
| 163 | new->prev = old->prev; | |
| 164 | new->prev->next = new; | |
| 165 | } | |
| 166 | ||
| 167 | static inline void list_replace_init(struct list_head *old, | |
| 168 | struct list_head *new) | |
| 169 | { | |
| 170 | list_replace(old, new); | |
| 171 | INIT_LIST_HEAD(old); | |
| 172 | } | |
| 173 | ||
| 174 | /** | |
| 175 | * list_del_init - deletes entry from list and reinitialize it. | |
| 176 | * @entry: the element to delete from the list. | |
| 177 | */ | |
| 178 | static inline void list_del_init(struct list_head *entry) | |
| 179 | { | |
| 180 | __list_del(entry->prev, entry->next); | |
| 181 | INIT_LIST_HEAD(entry); | |
| 182 | } | |
| 183 | ||
| 184 | /** | |
| 185 | * list_move - delete from one list and add as another's head | |
| 186 | * @list: the entry to move | |
| 187 | * @head: the head that will precede our entry | |
| 188 | */ | |
| 189 | static inline void list_move(struct list_head *list, struct list_head *head) | |
| 190 | { | |
| 191 | __list_del(list->prev, list->next); | |
| 192 | list_add(list, head); | |
| 193 | } | |
| 194 | ||
| 195 | /** | |
| 196 | * list_move_tail - delete from one list and add as another's tail | |
| 197 | * @list: the entry to move | |
| 198 | * @head: the head that will follow our entry | |
| 199 | */ | |
| 200 | static inline void list_move_tail(struct list_head *list, | |
| 201 | struct list_head *head) | |
| 202 | { | |
| 203 | __list_del(list->prev, list->next); | |
| 204 | list_add_tail(list, head); | |
| 205 | } | |
| 206 | ||
| 207 | /** | |
| 208 | * list_is_last - tests whether @list is the last entry in list @head | |
| 209 | * @list: the entry to test | |
| 210 | * @head: the head of the list | |
| 211 | */ | |
| 212 | static inline int list_is_last(const struct list_head *list, | |
| 213 | const struct list_head *head) | |
| 214 | { | |
| 215 | return list->next == head; | |
| 216 | } | |
| 217 | ||
| 218 | /** | |
| 219 | * list_empty - tests whether a list is empty | |
| 220 | * @head: the list to test. | |
| 221 | */ | |
| 222 | static inline int list_empty(const struct list_head *head) | |
| 223 | { | |
| 224 | return head->next == head; | |
| 225 | } | |
| 226 | ||
| 227 | /** | |
| 228 | * list_empty_careful - tests whether a list is empty and not being modified | |
| 229 | * @head: the list to test | |
| 230 | * | |
| 231 | * Description: | |
| 232 | * tests whether a list is empty _and_ checks that no other CPU might be | |
| 233 | * in the process of modifying either member (next or prev) | |
| 234 | * | |
| 235 | * NOTE: using list_empty_careful() without synchronization | |
| 236 | * can only be safe if the only activity that can happen | |
| 237 | * to the list entry is list_del_init(). Eg. it cannot be used | |
| 238 | * if another CPU could re-list_add() it. | |
| 239 | */ | |
| 240 | static inline int list_empty_careful(const struct list_head *head) | |
| 241 | { | |
| 242 | struct list_head *next = head->next; | |
| 243 | return (next == head) && (next == head->prev); | |
| 244 | } | |
| 245 | ||
| 246 | /** | |
| 247 | * list_is_singular - tests whether a list has just one entry. | |
| 248 | * @head: the list to test. | |
| 249 | */ | |
| 250 | static inline int list_is_singular(const struct list_head *head) | |
| 251 | { | |
| 252 | return !list_empty(head) && (head->next == head->prev); | |
| 253 | } | |
| 254 | ||
| 255 | static inline void __list_cut_position(struct list_head *list, | |
| 256 | struct list_head *head, struct list_head *entry) | |
| 257 | { | |
| 258 | struct list_head *new_first = entry->next; | |
| 259 | list->next = head->next; | |
| 260 | list->next->prev = list; | |
| 261 | list->prev = entry; | |
| 262 | entry->next = list; | |
| 263 | head->next = new_first; | |
| 264 | new_first->prev = head; | |
| 265 | } | |
| 266 | ||
| 267 | /** | |
| 268 | * list_cut_position - cut a list into two | |
| 269 | * @list: a new list to add all removed entries | |
| 270 | * @head: a list with entries | |
| 271 | * @entry: an entry within head, could be the head itself | |
| 272 | * and if so we won't cut the list | |
| 273 | * | |
| 274 | * This helper moves the initial part of @head, up to and | |
| 275 | * including @entry, from @head to @list. You should | |
| 276 | * pass on @entry an element you know is on @head. @list | |
| 277 | * should be an empty list or a list you do not care about | |
| 278 | * losing its data. | |
| 279 | * | |
| 280 | */ | |
| 281 | static inline void list_cut_position(struct list_head *list, | |
| 282 | struct list_head *head, struct list_head *entry) | |
| 283 | { | |
| 284 | if (list_empty(head)) | |
| 285 | return; | |
| 286 | if (list_is_singular(head) && | |
| 287 | (head->next != entry && head != entry)) | |
| 288 | return; | |
| 289 | if (entry == head) | |
| 290 | INIT_LIST_HEAD(list); | |
| 291 | else | |
| 292 | __list_cut_position(list, head, entry); | |
| 293 | } | |
| 294 | ||
| 295 | static inline void __list_splice(const struct list_head *list, | |
| 296 | struct list_head *prev, | |
| 297 | struct list_head *next) | |
| 298 | { | |
| 299 | struct list_head *first = list->next; | |
| 300 | struct list_head *last = list->prev; | |
| 301 | ||
| 302 | first->prev = prev; | |
| 303 | prev->next = first; | |
| 304 | ||
| 305 | last->next = next; | |
| 306 | next->prev = last; | |
| 307 | } | |
| 308 | ||
| 309 | /** | |
| 310 | * list_splice - join two lists, this is designed for stacks | |
| 311 | * @list: the new list to add. | |
| 312 | * @head: the place to add it in the first list. | |
| 313 | */ | |
| 314 | static inline void list_splice(const struct list_head *list, | |
| 315 | struct list_head *head) | |
| 316 | { | |
| 317 | if (!list_empty(list)) | |
| 318 | __list_splice(list, head, head->next); | |
| 319 | } | |
| 320 | ||
| 321 | /** | |
| 322 | * list_splice_tail - join two lists, each list being a queue | |
| 323 | * @list: the new list to add. | |
| 324 | * @head: the place to add it in the first list. | |
| 325 | */ | |
| 326 | static inline void list_splice_tail(struct list_head *list, | |
| 327 | struct list_head *head) | |
| 328 | { | |
| 329 | if (!list_empty(list)) | |
| 330 | __list_splice(list, head->prev, head); | |
| 331 | } | |
| 332 | ||
| 333 | /** | |
| 334 | * list_splice_init - join two lists and reinitialise the emptied list. | |
| 335 | * @list: the new list to add. | |
| 336 | * @head: the place to add it in the first list. | |
| 337 | * | |
| 338 | * The list at @list is reinitialised | |
| 339 | */ | |
| 340 | static inline void list_splice_init(struct list_head *list, | |
| 341 | struct list_head *head) | |
| 342 | { | |
| 343 | if (!list_empty(list)) { | |
| 344 | __list_splice(list, head, head->next); | |
| 345 | INIT_LIST_HEAD(list); | |
| 346 | } | |
| 347 | } | |
| 348 | ||
| 349 | /** | |
| 350 | * list_splice_tail_init - join two lists and reinitialise the emptied list | |
| 351 | * @list: the new list to add. | |
| 352 | * @head: the place to add it in the first list. | |
| 353 | * | |
| 354 | * Each of the lists is a queue. | |
| 355 | * The list at @list is reinitialised | |
| 356 | */ | |
| 357 | static inline void list_splice_tail_init(struct list_head *list, | |
| 358 | struct list_head *head) | |
| 359 | { | |
| 360 | if (!list_empty(list)) { | |
| 361 | __list_splice(list, head->prev, head); | |
| 362 | INIT_LIST_HEAD(list); | |
| 363 | } | |
| 364 | } | |
| 365 | ||
| 366 | /** | |
| 367 | * list_entry - get the struct for this entry | |
| 368 | * @ptr: the &struct list_head pointer. | |
| 369 | * @type: the type of the struct this is embedded in. | |
| 370 | * @member: the name of the list_struct within the struct. | |
| 371 | */ | |
| 372 | #define list_entry(ptr, type, member) \ | |
| 373 | container_of(ptr, type, member) | |
| 374 | ||
| 375 | /** | |
| 376 | * list_first_entry - get the first element from a list | |
| 377 | * @ptr: the list head to take the element from. | |
| 378 | * @type: the type of the struct this is embedded in. | |
| 379 | * @member: the name of the list_struct within the struct. | |
| 380 | * | |
| 381 | * Note, that list is expected to be not empty. | |
| 382 | */ | |
| 383 | #define list_first_entry(ptr, type, member) \ | |
| 384 | list_entry((ptr)->next, type, member) | |
| 385 | ||
| 386 | /** | |
| 387 | * list_for_each - iterate over a list | |
| 388 | * @pos: the &struct list_head to use as a loop cursor. | |
| 389 | * @head: the head for your list. | |
| 390 | */ | |
| 391 | #define list_for_each(pos, head) \ | |
| 392 | for (pos = (head)->next; prefetch(pos->next), pos != (head); \ | |
| 393 | pos = pos->next) | |
| 394 | ||
| 395 | /** | |
| 396 | * __list_for_each - iterate over a list | |
| 397 | * @pos: the &struct list_head to use as a loop cursor. | |
| 398 | * @head: the head for your list. | |
| 399 | * | |
| 400 | * This variant differs from list_for_each() in that it's the | |
| 401 | * simplest possible list iteration code, no prefetching is done. | |
| 402 | * Use this for code that knows the list to be very short (empty | |
| 403 | * or 1 entry) most of the time. | |
| 404 | */ | |
| 405 | #define __list_for_each(pos, head) \ | |
| 406 | for (pos = (head)->next; pos != (head); pos = pos->next) | |
| 407 | ||
| 408 | /** | |
| 409 | * list_for_each_prev - iterate over a list backwards | |
| 410 | * @pos: the &struct list_head to use as a loop cursor. | |
| 411 | * @head: the head for your list. | |
| 412 | */ | |
| 413 | #define list_for_each_prev(pos, head) \ | |
| 414 | for (pos = (head)->prev; prefetch(pos->prev), pos != (head); \ | |
| 415 | pos = pos->prev) | |
| 416 | ||
| 417 | /** | |
| 418 | * list_for_each_safe - iterate over a list safe against removal of list entry | |
| 419 | * @pos: the &struct list_head to use as a loop cursor. | |
| 420 | * @n: another &struct list_head to use as temporary storage | |
| 421 | * @head: the head for your list. | |
| 422 | */ | |
| 423 | #define list_for_each_safe(pos, n, head) \ | |
| 424 | for (pos = (head)->next, n = pos->next; pos != (head); \ | |
| 425 | pos = n, n = pos->next) | |
| 426 | ||
| 427 | /** | |
| 428 | * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry | |
| 429 | * @pos: the &struct list_head to use as a loop cursor. | |
| 430 | * @n: another &struct list_head to use as temporary storage | |
| 431 | * @head: the head for your list. | |
| 432 | */ | |
| 433 | #define list_for_each_prev_safe(pos, n, head) \ | |
| 434 | for (pos = (head)->prev, n = pos->prev; \ | |
| 435 | prefetch(pos->prev), pos != (head); \ | |
| 436 | pos = n, n = pos->prev) | |
| 437 | ||
| 438 | /** | |
| 439 | * list_for_each_entry - iterate over list of given type | |
| 440 | * @pos: the type * to use as a loop cursor. | |
| 441 | * @head: the head for your list. | |
| 442 | * @member: the name of the list_struct within the struct. | |
| 443 | */ | |
| 444 | #define list_for_each_entry(pos, head, member) \ | |
| 445 | for (pos = list_entry((head)->next, typeof(*pos), member); \ | |
| 446 | prefetch(pos->member.next), &pos->member != (head); \ | |
| 447 | pos = list_entry(pos->member.next, typeof(*pos), member)) | |
| 448 | ||
| 449 | /** | |
| 450 | * list_for_each_entry_reverse - iterate backwards over list of given type. | |
| 451 | * @pos: the type * to use as a loop cursor. | |
| 452 | * @head: the head for your list. | |
| 453 | * @member: the name of the list_struct within the struct. | |
| 454 | */ | |
| 455 | #define list_for_each_entry_reverse(pos, head, member) \ | |
| 456 | for (pos = list_entry((head)->prev, typeof(*pos), member); \ | |
| 457 | prefetch(pos->member.prev), &pos->member != (head); \ | |
| 458 | pos = list_entry(pos->member.prev, typeof(*pos), member)) | |
| 459 | ||
| 460 | /** | |
| 461 | * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue() | |
| 462 | * @pos: the type * to use as a start point | |
| 463 | * @head: the head of the list | |
| 464 | * @member: the name of the list_struct within the struct. | |
| 465 | * | |
| 466 | * Prepares a pos entry for use as a start point in list_for_each_entry_continue(). | |
| 467 | */ | |
| 468 | #define list_prepare_entry(pos, head, member) \ | |
| 469 | ((pos) ? : list_entry(head, typeof(*pos), member)) | |
| 470 | ||
| 471 | /** | |
| 472 | * list_for_each_entry_continue - continue iteration over list of given type | |
| 473 | * @pos: the type * to use as a loop cursor. | |
| 474 | * @head: the head for your list. | |
| 475 | * @member: the name of the list_struct within the struct. | |
| 476 | * | |
| 477 | * Continue to iterate over list of given type, continuing after | |
| 478 | * the current position. | |
| 479 | */ | |
| 480 | #define list_for_each_entry_continue(pos, head, member) \ | |
| 481 | for (pos = list_entry(pos->member.next, typeof(*pos), member); \ | |
| 482 | prefetch(pos->member.next), &pos->member != (head); \ | |
| 483 | pos = list_entry(pos->member.next, typeof(*pos), member)) | |
| 484 | ||
| 485 | /** | |
| 486 | * list_for_each_entry_continue_reverse - iterate backwards from the given point | |
| 487 | * @pos: the type * to use as a loop cursor. | |
| 488 | * @head: the head for your list. | |
| 489 | * @member: the name of the list_struct within the struct. | |
| 490 | * | |
| 491 | * Start to iterate over list of given type backwards, continuing after | |
| 492 | * the current position. | |
| 493 | */ | |
| 494 | #define list_for_each_entry_continue_reverse(pos, head, member) \ | |
| 495 | for (pos = list_entry(pos->member.prev, typeof(*pos), member); \ | |
| 496 | prefetch(pos->member.prev), &pos->member != (head); \ | |
| 497 | pos = list_entry(pos->member.prev, typeof(*pos), member)) | |
| 498 | ||
| 499 | /** | |
| 500 | * list_for_each_entry_from - iterate over list of given type from the current point | |
| 501 | * @pos: the type * to use as a loop cursor. | |
| 502 | * @head: the head for your list. | |
| 503 | * @member: the name of the list_struct within the struct. | |
| 504 | * | |
| 505 | * Iterate over list of given type, continuing from current position. | |
| 506 | */ | |
| 507 | #define list_for_each_entry_from(pos, head, member) \ | |
| 508 | for (; prefetch(pos->member.next), &pos->member != (head); \ | |
| 509 | pos = list_entry(pos->member.next, typeof(*pos), member)) | |
| 510 | ||
| 511 | /** | |
| 512 | * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry | |
| 513 | * @pos: the type * to use as a loop cursor. | |
| 514 | * @n: another type * to use as temporary storage | |
| 515 | * @head: the head for your list. | |
| 516 | * @member: the name of the list_struct within the struct. | |
| 517 | */ | |
| 518 | #define list_for_each_entry_safe(pos, n, head, member) \ | |
| 519 | for (pos = list_entry((head)->next, typeof(*pos), member), \ | |
| 520 | n = list_entry(pos->member.next, typeof(*pos), member); \ | |
| 521 | &pos->member != (head); \ | |
| 522 | pos = n, n = list_entry(n->member.next, typeof(*n), member)) | |
| 523 | ||
| 524 | /** | |
| 525 | * list_for_each_entry_safe_continue | |
| 526 | * @pos: the type * to use as a loop cursor. | |
| 527 | * @n: another type * to use as temporary storage | |
| 528 | * @head: the head for your list. | |
| 529 | * @member: the name of the list_struct within the struct. | |
| 530 | * | |
| 531 | * Iterate over list of given type, continuing after current point, | |
| 532 | * safe against removal of list entry. | |
| 533 | */ | |
| 534 | #define list_for_each_entry_safe_continue(pos, n, head, member) \ | |
| 535 | for (pos = list_entry(pos->member.next, typeof(*pos), member), \ | |
| 536 | n = list_entry(pos->member.next, typeof(*pos), member); \ | |
| 537 | &pos->member != (head); \ | |
| 538 | pos = n, n = list_entry(n->member.next, typeof(*n), member)) | |
| 539 | ||
| 540 | /** | |
| 541 | * list_for_each_entry_safe_from | |
| 542 | * @pos: the type * to use as a loop cursor. | |
| 543 | * @n: another type * to use as temporary storage | |
| 544 | * @head: the head for your list. | |
| 545 | * @member: the name of the list_struct within the struct. | |
| 546 | * | |
| 547 | * Iterate over list of given type from current point, safe against | |
| 548 | * removal of list entry. | |
| 549 | */ | |
| 550 | #define list_for_each_entry_safe_from(pos, n, head, member) \ | |
| 551 | for (n = list_entry(pos->member.next, typeof(*pos), member); \ | |
| 552 | &pos->member != (head); \ | |
| 553 | pos = n, n = list_entry(n->member.next, typeof(*n), member)) | |
| 554 | ||
| 555 | /** | |
| 556 | * list_for_each_entry_safe_reverse | |
| 557 | * @pos: the type * to use as a loop cursor. | |
| 558 | * @n: another type * to use as temporary storage | |
| 559 | * @head: the head for your list. | |
| 560 | * @member: the name of the list_struct within the struct. | |
| 561 | * | |
| 562 | * Iterate backwards over list of given type, safe against removal | |
| 563 | * of list entry. | |
| 564 | */ | |
| 565 | #define list_for_each_entry_safe_reverse(pos, n, head, member) \ | |
| 566 | for (pos = list_entry((head)->prev, typeof(*pos), member), \ | |
| 567 | n = list_entry(pos->member.prev, typeof(*pos), member); \ | |
| 568 | &pos->member != (head); \ | |
| 569 | pos = n, n = list_entry(n->member.prev, typeof(*n), member)) | |
| 570 | ||
| 571 | /* | |
| 572 | * Double linked lists with a single pointer list head. | |
| 573 | * Mostly useful for hash tables where the two pointer list head is | |
| 574 | * too wasteful. | |
| 575 | * You lose the ability to access the tail in O(1). | |
| 576 | */ | |
| 577 | ||
| 578 | struct hlist_head { | |
| 579 | struct hlist_node *first; | |
| 580 | }; | |
| 581 | ||
| 582 | struct hlist_node { | |
| 583 | struct hlist_node *next, **pprev; | |
| 584 | }; | |
| 585 | ||
| 586 | #define HLIST_HEAD_INIT { .first = NULL } | |
| 587 | #define HLIST_HEAD(name) struct hlist_head name = { .first = NULL } | |
| 588 | #define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL) | |
| 589 | static inline void INIT_HLIST_NODE(struct hlist_node *h) | |
| 590 | { | |
| 591 | h->next = NULL; | |
| 592 | h->pprev = NULL; | |
| 593 | } | |
| 594 | ||
| 595 | static inline int hlist_unhashed(const struct hlist_node *h) | |
| 596 | { | |
| 597 | return !h->pprev; | |
| 598 | } | |
| 599 | ||
| 600 | static inline int hlist_empty(const struct hlist_head *h) | |
| 601 | { | |
| 602 | return !h->first; | |
| 603 | } | |
| 604 | ||
| 605 | static inline void __hlist_del(struct hlist_node *n) | |
| 606 | { | |
| 607 | struct hlist_node *next = n->next; | |
| 608 | struct hlist_node **pprev = n->pprev; | |
| 609 | *pprev = next; | |
| 610 | if (next) | |
| 611 | next->pprev = pprev; | |
| 612 | } | |
| 613 | ||
| 614 | static inline void hlist_del(struct hlist_node *n) | |
| 615 | { | |
| 616 | __hlist_del(n); | |
| 617 | n->next = LIST_POISON1; | |
| 618 | n->pprev = LIST_POISON2; | |
| 619 | } | |
| 620 | ||
| 621 | static inline void hlist_del_init(struct hlist_node *n) | |
| 622 | { | |
| 623 | if (!hlist_unhashed(n)) { | |
| 624 | __hlist_del(n); | |
| 625 | INIT_HLIST_NODE(n); | |
| 626 | } | |
| 627 | } | |
| 628 | ||
| 629 | static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h) | |
| 630 | { | |
| 631 | struct hlist_node *first = h->first; | |
| 632 | n->next = first; | |
| 633 | if (first) | |
| 634 | first->pprev = &n->next; | |
| 635 | h->first = n; | |
| 636 | n->pprev = &h->first; | |
| 637 | } | |
| 638 | ||
| 639 | /* next must be != NULL */ | |
| 640 | static inline void hlist_add_before(struct hlist_node *n, | |
| 641 | struct hlist_node *next) | |
| 642 | { | |
| 643 | n->pprev = next->pprev; | |
| 644 | n->next = next; | |
| 645 | next->pprev = &n->next; | |
| 646 | *(n->pprev) = n; | |
| 647 | } | |
| 648 | ||
| 649 | static inline void hlist_add_after(struct hlist_node *n, | |
| 650 | struct hlist_node *next) | |
| 651 | { | |
| 652 | next->next = n->next; | |
| 653 | n->next = next; | |
| 654 | next->pprev = &n->next; | |
| 655 | ||
| 656 | if(next->next) | |
| 657 | next->next->pprev = &next->next; | |
| 658 | } | |
| 659 | ||
| 660 | #define hlist_entry(ptr, type, member) container_of(ptr,type,member) | |
| 661 | ||
| 662 | #define hlist_for_each(pos, head) \ | |
| 663 | for (pos = (head)->first; pos && ({ prefetch(pos->next); 1; }); \ | |
| 664 | pos = pos->next) | |
| 665 | ||
| 666 | #define hlist_for_each_safe(pos, n, head) \ | |
| 667 | for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \ | |
| 668 | pos = n) | |
| 669 | ||
| 670 | /** | |
| 671 | * hlist_for_each_entry - iterate over list of given type | |
| 672 | * @tpos: the type * to use as a loop cursor. | |
| 673 | * @pos: the &struct hlist_node to use as a loop cursor. | |
| 674 | * @head: the head for your list. | |
| 675 | * @member: the name of the hlist_node within the struct. | |
| 676 | */ | |
| 677 | #define hlist_for_each_entry(tpos, pos, head, member) \ | |
| 678 | for (pos = (head)->first; \ | |
| 679 | pos && ({ prefetch(pos->next); 1;}) && \ | |
| 680 | ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ | |
| 681 | pos = pos->next) | |
| 682 | ||
| 683 | /** | |
| 684 | * hlist_for_each_entry_continue - iterate over a hlist continuing after current point | |
| 685 | * @tpos: the type * to use as a loop cursor. | |
| 686 | * @pos: the &struct hlist_node to use as a loop cursor. | |
| 687 | * @member: the name of the hlist_node within the struct. | |
| 688 | */ | |
| 689 | #define hlist_for_each_entry_continue(tpos, pos, member) \ | |
| 690 | for (pos = (pos)->next; \ | |
| 691 | pos && ({ prefetch(pos->next); 1;}) && \ | |
| 692 | ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ | |
| 693 | pos = pos->next) | |
| 694 | ||
| 695 | /** | |
| 696 | * hlist_for_each_entry_from - iterate over a hlist continuing from current point | |
| 697 | * @tpos: the type * to use as a loop cursor. | |
| 698 | * @pos: the &struct hlist_node to use as a loop cursor. | |
| 699 | * @member: the name of the hlist_node within the struct. | |
| 700 | */ | |
| 701 | #define hlist_for_each_entry_from(tpos, pos, member) \ | |
| 702 | for (; pos && ({ prefetch(pos->next); 1;}) && \ | |
| 703 | ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ | |
| 704 | pos = pos->next) | |
| 705 | ||
| 706 | /** | |
| 707 | * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry | |
| 708 | * @tpos: the type * to use as a loop cursor. | |
| 709 | * @pos: the &struct hlist_node to use as a loop cursor. | |
| 710 | * @n: another &struct hlist_node to use as temporary storage | |
| 711 | * @head: the head for your list. | |
| 712 | * @member: the name of the hlist_node within the struct. | |
| 713 | */ | |
| 714 | #define hlist_for_each_entry_safe(tpos, pos, n, head, member) \ | |
| 715 | for (pos = (head)->first; \ | |
| 716 | pos && ({ n = pos->next; 1; }) && \ | |
| 717 | ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \ | |
| 718 | pos = n) | |
| 719 | ||
| 720 | ||
| 721 | #endif | |
| 722 | ||
| 723 | ||
