1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _LINUX_LIST_H
3#define _LINUX_LIST_H
4
5#include <linux/types.h>
6#include <linux/stddef.h>
7#include <linux/poison.h>
8#include <linux/const.h>
9#include <linux/kernel.h>
10
11/*
12 * Simple doubly linked list implementation.
13 *
14 * Some of the internal functions ("__xxx") are useful when
15 * manipulating whole lists rather than single entries, as
16 * sometimes we already know the next/prev entries and we can
17 * generate better code by using them directly rather than
18 * using the generic single-entry routines.
19 */
20
21#define LIST_HEAD_INIT(name) { &(name), &(name) }
22
23#define LIST_HEAD(name) \
24 struct list_head name = LIST_HEAD_INIT(name)
25
26static inline void INIT_LIST_HEAD(struct list_head *list)
27{
28 WRITE_ONCE(list->next, list);
29 list->prev = list;
30}
31
32#ifdef CONFIG_DEBUG_LIST
33extern bool __list_add_valid(struct list_head *new,
34 struct list_head *prev,
35 struct list_head *next);
36extern bool __list_del_entry_valid(struct list_head *entry);
37#else
38static inline bool __list_add_valid(struct list_head *new,
39 struct list_head *prev,
40 struct list_head *next)
41{
42 return true;
43}
44static inline bool __list_del_entry_valid(struct list_head *entry)
45{
46 return true;
47}
48#endif
49
50/*
51 * Insert a new entry between two known consecutive entries.
52 *
53 * This is only for internal list manipulation where we know
54 * the prev/next entries already!
55 */
56static inline void __list_add(struct list_head *new,
57 struct list_head *prev,
58 struct list_head *next)
59{
60 if (!__list_add_valid(new, prev, next))
61 return;
62
63 next->prev = new;
64 new->next = next;
65 new->prev = prev;
66 WRITE_ONCE(prev->next, new);
67}
68
69/**
70 * list_add - add a new entry
71 * @new: new entry to be added
72 * @head: list head to add it after
73 *
74 * Insert a new entry after the specified head.
75 * This is good for implementing stacks.
76 */
77static inline void list_add(struct list_head *new, struct list_head *head)
78{
79 __list_add(new, head, head->next);
80}
81
82
83/**
84 * list_add_tail - add a new entry
85 * @new: new entry to be added
86 * @head: list head to add it before
87 *
88 * Insert a new entry before the specified head.
89 * This is useful for implementing queues.
90 */
91static inline void list_add_tail(struct list_head *new, struct list_head *head)
92{
93 __list_add(new, head->prev, head);
94}
95
96/*
97 * Delete a list entry by making the prev/next entries
98 * point to each other.
99 *
100 * This is only for internal list manipulation where we know
101 * the prev/next entries already!
102 */
103static inline void __list_del(struct list_head * prev, struct list_head * next)
104{
105 next->prev = prev;
106 WRITE_ONCE(prev->next, next);
107}
108
109/**
110 * list_del - deletes entry from list.
111 * @entry: the element to delete from the list.
112 * Note: list_empty() on entry does not return true after this, the entry is
113 * in an undefined state.
114 */
115static inline void __list_del_entry(struct list_head *entry)
116{
117 if (!__list_del_entry_valid(entry))
118 return;
119
120 __list_del(entry->prev, entry->next);
121}
122
123static inline void list_del(struct list_head *entry)
124{
125 __list_del_entry(entry);
126 entry->next = LIST_POISON1;
127 entry->prev = LIST_POISON2;
128}
129
130/**
131 * list_replace - replace old entry by new one
132 * @old : the element to be replaced
133 * @new : the new element to insert
134 *
135 * If @old was empty, it will be overwritten.
136 */
137static inline void list_replace(struct list_head *old,
138 struct list_head *new)
139{
140 new->next = old->next;
141 new->next->prev = new;
142 new->prev = old->prev;
143 new->prev->next = new;
144}
145
146static inline void list_replace_init(struct list_head *old,
147 struct list_head *new)
148{
149 list_replace(old, new);
150 INIT_LIST_HEAD(old);
151}
152
153/**
154 * list_del_init - deletes entry from list and reinitialize it.
155 * @entry: the element to delete from the list.
156 */
157static inline void list_del_init(struct list_head *entry)
158{
159 __list_del_entry(entry);
160 INIT_LIST_HEAD(entry);
161}
162
163/**
164 * list_move - delete from one list and add as another's head
165 * @list: the entry to move
166 * @head: the head that will precede our entry
167 */
168static inline void list_move(struct list_head *list, struct list_head *head)
169{
170 __list_del_entry(list);
171 list_add(list, head);
172}
173
174/**
175 * list_move_tail - delete from one list and add as another's tail
176 * @list: the entry to move
177 * @head: the head that will follow our entry
178 */
179static inline void list_move_tail(struct list_head *list,
180 struct list_head *head)
181{
182 __list_del_entry(list);
183 list_add_tail(list, head);
184}
185
186/**
187 * list_bulk_move_tail - move a subsection of a list to its tail
188 * @head: the head that will follow our entry
189 * @first: first entry to move
190 * @last: last entry to move, can be the same as first
191 *
192 * Move all entries between @first and including @last before @head.
193 * All three entries must belong to the same linked list.
194 */
195static inline void list_bulk_move_tail(struct list_head *head,
196 struct list_head *first,
197 struct list_head *last)
198{
199 first->prev->next = last->next;
200 last->next->prev = first->prev;
201
202 head->prev->next = first;
203 first->prev = head->prev;
204
205 last->next = head;
206 head->prev = last;
207}
208
209/**
210 * list_is_first -- tests whether @ list is the first entry in list @head
211 * @list: the entry to test
212 * @head: the head of the list
213 */
214static inline int list_is_first(const struct list_head *list,
215 const struct list_head *head)
216{
217 return list->prev == head;
218}
219
220/**
221 * list_is_last - tests whether @list is the last entry in list @head
222 * @list: the entry to test
223 * @head: the head of the list
224 */
225static inline int list_is_last(const struct list_head *list,
226 const struct list_head *head)
227{
228 return list->next == head;
229}
230
231/**
232 * list_empty - tests whether a list is empty
233 * @head: the list to test.
234 */
235static inline int list_empty(const struct list_head *head)
236{
237 return READ_ONCE(head->next) == head;
238}
239
240/**
241 * list_empty_careful - tests whether a list is empty and not being modified
242 * @head: the list to test
243 *
244 * Description:
245 * tests whether a list is empty _and_ checks that no other CPU might be
246 * in the process of modifying either member (next or prev)
247 *
248 * NOTE: using list_empty_careful() without synchronization
249 * can only be safe if the only activity that can happen
250 * to the list entry is list_del_init(). Eg. it cannot be used
251 * if another CPU could re-list_add() it.
252 */
253static inline int list_empty_careful(const struct list_head *head)
254{
255 struct list_head *next = head->next;
256 return (next == head) && (next == head->prev);
257}
258
259/**
260 * list_rotate_left - rotate the list to the left
261 * @head: the head of the list
262 */
263static inline void list_rotate_left(struct list_head *head)
264{
265 struct list_head *first;
266
267 if (!list_empty(head)) {
268 first = head->next;
269 list_move_tail(first, head);
270 }
271}
272
273/**
274 * list_is_singular - tests whether a list has just one entry.
275 * @head: the list to test.
276 */
277static inline int list_is_singular(const struct list_head *head)
278{
279 return !list_empty(head) && (head->next == head->prev);
280}
281
282static inline void __list_cut_position(struct list_head *list,
283 struct list_head *head, struct list_head *entry)
284{
285 struct list_head *new_first = entry->next;
286 list->next = head->next;
287 list->next->prev = list;
288 list->prev = entry;
289 entry->next = list;
290 head->next = new_first;
291 new_first->prev = head;
292}
293
294/**
295 * list_cut_position - cut a list into two
296 * @list: a new list to add all removed entries
297 * @head: a list with entries
298 * @entry: an entry within head, could be the head itself
299 * and if so we won't cut the list
300 *
301 * This helper moves the initial part of @head, up to and
302 * including @entry, from @head to @list. You should
303 * pass on @entry an element you know is on @head. @list
304 * should be an empty list or a list you do not care about
305 * losing its data.
306 *
307 */
308static inline void list_cut_position(struct list_head *list,
309 struct list_head *head, struct list_head *entry)
310{
311 if (list_empty(head))
312 return;
313 if (list_is_singular(head) &&
314 (head->next != entry && head != entry))
315 return;
316 if (entry == head)
317 INIT_LIST_HEAD(list);
318 else
319 __list_cut_position(list, head, entry);
320}
321
322/**
323 * list_cut_before - cut a list into two, before given entry
324 * @list: a new list to add all removed entries
325 * @head: a list with entries
326 * @entry: an entry within head, could be the head itself
327 *
328 * This helper moves the initial part of @head, up to but
329 * excluding @entry, from @head to @list. You should pass
330 * in @entry an element you know is on @head. @list should
331 * be an empty list or a list you do not care about losing
332 * its data.
333 * If @entry == @head, all entries on @head are moved to
334 * @list.
335 */
336static inline void list_cut_before(struct list_head *list,
337 struct list_head *head,
338 struct list_head *entry)
339{
340 if (head->next == entry) {
341 INIT_LIST_HEAD(list);
342 return;
343 }
344 list->next = head->next;
345 list->next->prev = list;
346 list->prev = entry->prev;
347 list->prev->next = list;
348 head->next = entry;
349 entry->prev = head;
350}
351
352static inline void __list_splice(const struct list_head *list,
353 struct list_head *prev,
354 struct list_head *next)
355{
356 struct list_head *first = list->next;
357 struct list_head *last = list->prev;
358
359 first->prev = prev;
360 prev->next = first;
361
362 last->next = next;
363 next->prev = last;
364}
365
366/**
367 * list_splice - join two lists, this is designed for stacks
368 * @list: the new list to add.
369 * @head: the place to add it in the first list.
370 */
371static inline void list_splice(const struct list_head *list,
372 struct list_head *head)
373{
374 if (!list_empty(list))
375 __list_splice(list, head, head->next);
376}
377
378/**
379 * list_splice_tail - join two lists, each list being a queue
380 * @list: the new list to add.
381 * @head: the place to add it in the first list.
382 */
383static inline void list_splice_tail(struct list_head *list,
384 struct list_head *head)
385{
386 if (!list_empty(list))
387 __list_splice(list, head->prev, head);
388}
389
390/**
391 * list_splice_init - join two lists and reinitialise the emptied list.
392 * @list: the new list to add.
393 * @head: the place to add it in the first list.
394 *
395 * The list at @list is reinitialised
396 */
397static inline void list_splice_init(struct list_head *list,
398 struct list_head *head)
399{
400 if (!list_empty(list)) {
401 __list_splice(list, head, head->next);
402 INIT_LIST_HEAD(list);
403 }
404}
405
406/**
407 * list_splice_tail_init - join two lists and reinitialise the emptied list
408 * @list: the new list to add.
409 * @head: the place to add it in the first list.
410 *
411 * Each of the lists is a queue.
412 * The list at @list is reinitialised
413 */
414static inline void list_splice_tail_init(struct list_head *list,
415 struct list_head *head)
416{
417 if (!list_empty(list)) {
418 __list_splice(list, head->prev, head);
419 INIT_LIST_HEAD(list);
420 }
421}
422
423/**
424 * list_entry - get the struct for this entry
425 * @ptr: the &struct list_head pointer.
426 * @type: the type of the struct this is embedded in.
427 * @member: the name of the list_head within the struct.
428 */
429#define list_entry(ptr, type, member) \
430 container_of(ptr, type, member)
431
432/**
433 * list_first_entry - get the first element from a list
434 * @ptr: the list head to take the element from.
435 * @type: the type of the struct this is embedded in.
436 * @member: the name of the list_head within the struct.
437 *
438 * Note, that list is expected to be not empty.
439 */
440#define list_first_entry(ptr, type, member) \
441 list_entry((ptr)->next, type, member)
442
443/**
444 * list_last_entry - get the last element from a list
445 * @ptr: the list head to take the element from.
446 * @type: the type of the struct this is embedded in.
447 * @member: the name of the list_head within the struct.
448 *
449 * Note, that list is expected to be not empty.
450 */
451#define list_last_entry(ptr, type, member) \
452 list_entry((ptr)->prev, type, member)
453
454/**
455 * list_first_entry_or_null - get the first element from a list
456 * @ptr: the list head to take the element from.
457 * @type: the type of the struct this is embedded in.
458 * @member: the name of the list_head within the struct.
459 *
460 * Note that if the list is empty, it returns NULL.
461 */
462#define list_first_entry_or_null(ptr, type, member) ({ \
463 struct list_head *head__ = (ptr); \
464 struct list_head *pos__ = READ_ONCE(head__->next); \
465 pos__ != head__ ? list_entry(pos__, type, member) : NULL; \
466})
467
468/**
469 * list_next_entry - get the next element in list
470 * @pos: the type * to cursor
471 * @member: the name of the list_head within the struct.
472 */
473#define list_next_entry(pos, member) \
474 list_entry((pos)->member.next, typeof(*(pos)), member)
475
476/**
477 * list_prev_entry - get the prev element in list
478 * @pos: the type * to cursor
479 * @member: the name of the list_head within the struct.
480 */
481#define list_prev_entry(pos, member) \
482 list_entry((pos)->member.prev, typeof(*(pos)), member)
483
484/**
485 * list_for_each - iterate over a list
486 * @pos: the &struct list_head to use as a loop cursor.
487 * @head: the head for your list.
488 */
489#define list_for_each(pos, head) \
490 for (pos = (head)->next; pos != (head); pos = pos->next)
491
492/**
493 * list_for_each_prev - iterate over a list backwards
494 * @pos: the &struct list_head to use as a loop cursor.
495 * @head: the head for your list.
496 */
497#define list_for_each_prev(pos, head) \
498 for (pos = (head)->prev; pos != (head); pos = pos->prev)
499
500/**
501 * list_for_each_safe - iterate over a list safe against removal of list entry
502 * @pos: the &struct list_head to use as a loop cursor.
503 * @n: another &struct list_head to use as temporary storage
504 * @head: the head for your list.
505 */
506#define list_for_each_safe(pos, n, head) \
507 for (pos = (head)->next, n = pos->next; pos != (head); \
508 pos = n, n = pos->next)
509
510/**
511 * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry
512 * @pos: the &struct list_head to use as a loop cursor.
513 * @n: another &struct list_head to use as temporary storage
514 * @head: the head for your list.
515 */
516#define list_for_each_prev_safe(pos, n, head) \
517 for (pos = (head)->prev, n = pos->prev; \
518 pos != (head); \
519 pos = n, n = pos->prev)
520
521/**
522 * list_for_each_entry - iterate over list of given type
523 * @pos: the type * to use as a loop cursor.
524 * @head: the head for your list.
525 * @member: the name of the list_head within the struct.
526 */
527#define list_for_each_entry(pos, head, member) \
528 for (pos = list_first_entry(head, typeof(*pos), member); \
529 &pos->member != (head); \
530 pos = list_next_entry(pos, member))
531
532/**
533 * list_for_each_entry_reverse - iterate backwards over list of given type.
534 * @pos: the type * to use as a loop cursor.
535 * @head: the head for your list.
536 * @member: the name of the list_head within the struct.
537 */
538#define list_for_each_entry_reverse(pos, head, member) \
539 for (pos = list_last_entry(head, typeof(*pos), member); \
540 &pos->member != (head); \
541 pos = list_prev_entry(pos, member))
542
543/**
544 * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue()
545 * @pos: the type * to use as a start point
546 * @head: the head of the list
547 * @member: the name of the list_head within the struct.
548 *
549 * Prepares a pos entry for use as a start point in list_for_each_entry_continue().
550 */
551#define list_prepare_entry(pos, head, member) \
552 ((pos) ? : list_entry(head, typeof(*pos), member))
553
554/**
555 * list_for_each_entry_continue - continue iteration over list of given type
556 * @pos: the type * to use as a loop cursor.
557 * @head: the head for your list.
558 * @member: the name of the list_head within the struct.
559 *
560 * Continue to iterate over list of given type, continuing after
561 * the current position.
562 */
563#define list_for_each_entry_continue(pos, head, member) \
564 for (pos = list_next_entry(pos, member); \
565 &pos->member != (head); \
566 pos = list_next_entry(pos, member))
567
568/**
569 * list_for_each_entry_continue_reverse - iterate backwards from the given point
570 * @pos: the type * to use as a loop cursor.
571 * @head: the head for your list.
572 * @member: the name of the list_head within the struct.
573 *
574 * Start to iterate over list of given type backwards, continuing after
575 * the current position.
576 */
577#define list_for_each_entry_continue_reverse(pos, head, member) \
578 for (pos = list_prev_entry(pos, member); \
579 &pos->member != (head); \
580 pos = list_prev_entry(pos, member))
581
582/**
583 * list_for_each_entry_from - iterate over list of given type from the current point
584 * @pos: the type * to use as a loop cursor.
585 * @head: the head for your list.
586 * @member: the name of the list_head within the struct.
587 *
588 * Iterate over list of given type, continuing from current position.
589 */
590#define list_for_each_entry_from(pos, head, member) \
591 for (; &pos->member != (head); \
592 pos = list_next_entry(pos, member))
593
594/**
595 * list_for_each_entry_from_reverse - iterate backwards over list of given type
596 * from the current point
597 * @pos: the type * to use as a loop cursor.
598 * @head: the head for your list.
599 * @member: the name of the list_head within the struct.
600 *
601 * Iterate backwards over list of given type, continuing from current position.
602 */
603#define list_for_each_entry_from_reverse(pos, head, member) \
604 for (; &pos->member != (head); \
605 pos = list_prev_entry(pos, member))
606
607/**
608 * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
609 * @pos: the type * to use as a loop cursor.
610 * @n: another type * to use as temporary storage
611 * @head: the head for your list.
612 * @member: the name of the list_head within the struct.
613 */
614#define list_for_each_entry_safe(pos, n, head, member) \
615 for (pos = list_first_entry(head, typeof(*pos), member), \
616 n = list_next_entry(pos, member); \
617 &pos->member != (head); \
618 pos = n, n = list_next_entry(n, member))
619
620/**
621 * list_for_each_entry_safe_continue - continue list iteration safe against removal
622 * @pos: the type * to use as a loop cursor.
623 * @n: another type * to use as temporary storage
624 * @head: the head for your list.
625 * @member: the name of the list_head within the struct.
626 *
627 * Iterate over list of given type, continuing after current point,
628 * safe against removal of list entry.
629 */
630#define list_for_each_entry_safe_continue(pos, n, head, member) \
631 for (pos = list_next_entry(pos, member), \
632 n = list_next_entry(pos, member); \
633 &pos->member != (head); \
634 pos = n, n = list_next_entry(n, member))
635
636/**
637 * list_for_each_entry_safe_from - iterate over list from current point safe against removal
638 * @pos: the type * to use as a loop cursor.
639 * @n: another type * to use as temporary storage
640 * @head: the head for your list.
641 * @member: the name of the list_head within the struct.
642 *
643 * Iterate over list of given type from current point, safe against
644 * removal of list entry.
645 */
646#define list_for_each_entry_safe_from(pos, n, head, member) \
647 for (n = list_next_entry(pos, member); \
648 &pos->member != (head); \
649 pos = n, n = list_next_entry(n, member))
650
651/**
652 * list_for_each_entry_safe_reverse - iterate backwards over list safe against removal
653 * @pos: the type * to use as a loop cursor.
654 * @n: another type * to use as temporary storage
655 * @head: the head for your list.
656 * @member: the name of the list_head within the struct.
657 *
658 * Iterate backwards over list of given type, safe against removal
659 * of list entry.
660 */
661#define list_for_each_entry_safe_reverse(pos, n, head, member) \
662 for (pos = list_last_entry(head, typeof(*pos), member), \
663 n = list_prev_entry(pos, member); \
664 &pos->member != (head); \
665 pos = n, n = list_prev_entry(n, member))
666
667/**
668 * list_safe_reset_next - reset a stale list_for_each_entry_safe loop
669 * @pos: the loop cursor used in the list_for_each_entry_safe loop
670 * @n: temporary storage used in list_for_each_entry_safe
671 * @member: the name of the list_head within the struct.
672 *
673 * list_safe_reset_next is not safe to use in general if the list may be
674 * modified concurrently (eg. the lock is dropped in the loop body). An
675 * exception to this is if the cursor element (pos) is pinned in the list,
676 * and list_safe_reset_next is called after re-taking the lock and before
677 * completing the current iteration of the loop body.
678 */
679#define list_safe_reset_next(pos, n, member) \
680 n = list_next_entry(pos, member)
681
682/*
683 * Double linked lists with a single pointer list head.
684 * Mostly useful for hash tables where the two pointer list head is
685 * too wasteful.
686 * You lose the ability to access the tail in O(1).
687 */
688
689#define HLIST_HEAD_INIT { .first = NULL }
690#define HLIST_HEAD(name) struct hlist_head name = { .first = NULL }
691#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL)
692static inline void INIT_HLIST_NODE(struct hlist_node *h)
693{
694 h->next = NULL;
695 h->pprev = NULL;
696}
697
698static inline int hlist_unhashed(const struct hlist_node *h)
699{
700 return !h->pprev;
701}
702
703static inline int hlist_empty(const struct hlist_head *h)
704{
705 return !READ_ONCE(h->first);
706}
707
708static inline void __hlist_del(struct hlist_node *n)
709{
710 struct hlist_node *next = n->next;
711 struct hlist_node **pprev = n->pprev;
712
713 WRITE_ONCE(*pprev, next);
714 if (next)
715 next->pprev = pprev;
716}
717
718static inline void hlist_del(struct hlist_node *n)
719{
720 __hlist_del(n);
721 n->next = LIST_POISON1;
722 n->pprev = LIST_POISON2;
723}
724
725static inline void hlist_del_init(struct hlist_node *n)
726{
727 if (!hlist_unhashed(n)) {
728 __hlist_del(n);
729 INIT_HLIST_NODE(n);
730 }
731}
732
733static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)
734{
735 struct hlist_node *first = h->first;
736 n->next = first;
737 if (first)
738 first->pprev = &n->next;
739 WRITE_ONCE(h->first, n);
740 n->pprev = &h->first;
741}
742
743/* next must be != NULL */
744static inline void hlist_add_before(struct hlist_node *n,
745 struct hlist_node *next)
746{
747 n->pprev = next->pprev;
748 n->next = next;
749 next->pprev = &n->next;
750 WRITE_ONCE(*(n->pprev), n);
751}
752
753static inline void hlist_add_behind(struct hlist_node *n,
754 struct hlist_node *prev)
755{
756 n->next = prev->next;
757 WRITE_ONCE(prev->next, n);
758 n->pprev = &prev->next;
759
760 if (n->next)
761 n->next->pprev = &n->next;
762}
763
764/* after that we'll appear to be on some hlist and hlist_del will work */
765static inline void hlist_add_fake(struct hlist_node *n)
766{
767 n->pprev = &n->next;
768}
769
770static inline bool hlist_fake(struct hlist_node *h)
771{
772 return h->pprev == &h->next;
773}
774
775/*
776 * Check whether the node is the only node of the head without
777 * accessing head:
778 */
779static inline bool
780hlist_is_singular_node(struct hlist_node *n, struct hlist_head *h)
781{
782 return !n->next && n->pprev == &h->first;
783}
784
785/*
786 * Move a list from one list head to another. Fixup the pprev
787 * reference of the first entry if it exists.
788 */
789static inline void hlist_move_list(struct hlist_head *old,
790 struct hlist_head *new)
791{
792 new->first = old->first;
793 if (new->first)
794 new->first->pprev = &new->first;
795 old->first = NULL;
796}
797
798#define hlist_entry(ptr, type, member) container_of(ptr,type,member)
799
800#define hlist_for_each(pos, head) \
801 for (pos = (head)->first; pos ; pos = pos->next)
802
803#define hlist_for_each_safe(pos, n, head) \
804 for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \
805 pos = n)
806
807#define hlist_entry_safe(ptr, type, member) \
808 ({ typeof(ptr) ____ptr = (ptr); \
809 ____ptr ? hlist_entry(____ptr, type, member) : NULL; \
810 })
811
812/**
813 * hlist_for_each_entry - iterate over list of given type
814 * @pos: the type * to use as a loop cursor.
815 * @head: the head for your list.
816 * @member: the name of the hlist_node within the struct.
817 */
818#define hlist_for_each_entry(pos, head, member) \
819 for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member);\
820 pos; \
821 pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member))
822
823/**
824 * hlist_for_each_entry_continue - iterate over a hlist continuing after current point
825 * @pos: the type * to use as a loop cursor.
826 * @member: the name of the hlist_node within the struct.
827 */
828#define hlist_for_each_entry_continue(pos, member) \
829 for (pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member);\
830 pos; \
831 pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member))
832
833/**
834 * hlist_for_each_entry_from - iterate over a hlist continuing from current point
835 * @pos: the type * to use as a loop cursor.
836 * @member: the name of the hlist_node within the struct.
837 */
838#define hlist_for_each_entry_from(pos, member) \
839 for (; pos; \
840 pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member))
841
842/**
843 * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry
844 * @pos: the type * to use as a loop cursor.
845 * @n: another &struct hlist_node to use as temporary storage
846 * @head: the head for your list.
847 * @member: the name of the hlist_node within the struct.
848 */
849#define hlist_for_each_entry_safe(pos, n, head, member) \
850 for (pos = hlist_entry_safe((head)->first, typeof(*pos), member);\
851 pos && ({ n = pos->member.next; 1; }); \
852 pos = hlist_entry_safe(n, typeof(*pos), member))
853
854#endif
855