1 /*
2 * Copyright (c) 2021 Chipsea Technologies (Shenzhen) Corp., Ltd. All rights reserved.
3 * Licensed under the Apache License, Version 2.0 (the "License");
4 * you may not use this file except in compliance with the License.
5 * You may obtain a copy of the License at
6 *
7 * http://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15 #ifndef _LNX_LIST_H_
16 #define _LNX_LIST_H_
17
18 /**
19 * *** Porting from linux kernel. ***
20 * NOTES:
21 * 1. armcc do not support typeof to retrieve the data type, direct use type.
22 * 2. prefetch is not support in current platform, remove.
23 *
24 * Simple doubly linked list implementation.
25 *
26 * Some of the internal functions ("__xxx") are useful when
27 * manipulating whole lists rather than single entries, as
28 * sometimes we already know the next/prev entries and we can
29 * generate better code by using them directly rather than
30 * using the generic single-entry routines.
31 */
32
33 /*****************************************************************************/
34 /* File Includes */
35 /*****************************************************************************/
36
37 #include "cmsis_compiler.h"
38
39 /*****************************************************************************/
40 /* Porting Modification */
41 /*****************************************************************************/
42
43 #ifndef size_t
44 typedef unsigned int size_t;
45 #endif /* size_t */
46
47 #ifndef offsetof
48 /**
49 * expands to an integral constant expression that has type size_t, the
50 * value of which is the offset in bytes, from the beginning of a structure
51 * designated by type, of the member designated by the identifier (if the
52 * specified member is a bit-field, the behaviour is undefined).
53 */
54 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
55 #endif
56
57 #ifndef container_of
58 /**
59 * container_of - cast a member of a structure out to the containing structure
60 * \param ptr: the pointer to the member.
61 * \param type: the type of the container struct this is embedded in.
62 * \param member: the name of the member within the struct.
63 *
64 */
65 #define container_of(ptr, type, member) \
66 (type *)((char *)ptr - offsetof(type,member))
67 #endif
68
69 /*****************************************************************************/
70 /* Constants Definitions */
71 /*****************************************************************************/
72
73 /*
74 * These are non-NULL pointers that will result in page faults
75 * under normal circumstances, used to verify that nobody uses
76 * non-initialized list entries.
77 */
78 //#define LIST_POISON1 ((void *) 0x00100200)
79 //#define LIST_POISON2 ((void *) 0x00200200)
80 #define LIST_POISON1 NULL
81 #define LIST_POISON2 NULL
82
83 struct list_head
84 {
85 struct list_head *next, *prev;
86 };
87
88 #define LIST_HEAD_INIT(name) { &(name), &(name) }
89
90 #define LIST_HEAD(name) \
91 struct list_head name = LIST_HEAD_INIT(name)
92
INIT_LIST_HEAD(struct list_head * list)93 __STATIC_INLINE void INIT_LIST_HEAD(struct list_head *list)
94 {
95 list->next = list;
96 list->prev = list;
97 }
98
99 /*
100 * Insert a new entry between two known consecutive entries.
101 *
102 * This is only for internal list manipulation where we know
103 * the prev/next entries already!
104 */
__list_add(struct list_head * new,struct list_head * prev,struct list_head * next)105 __STATIC_INLINE void __list_add(struct list_head *new,
106 struct list_head *prev, struct list_head *next)
107 {
108 next->prev = new;
109 new->next = next;
110 new->prev = prev;
111 prev->next = new;
112 }
113
114 /**
115 * list_add - add a new entry
116 * \param new: new entry to be added
117 * \param head: list head to add it after
118 *
119 * Insert a new entry after the specified head.
120 * This is good for implementing stacks.
121 */
list_add(struct list_head * new,struct list_head * head)122 __STATIC_INLINE void list_add(struct list_head *new, struct list_head *head)
123 {
124 __list_add(new, head, head->next);
125 }
126
127 /**
128 * list_add_tail - add a new entry
129 * \param new: new entry to be added
130 * \param head: list head to add it before
131 *
132 * Insert a new entry before the specified head.
133 * This is useful for implementing queues.
134 */
list_add_tail(struct list_head * new,struct list_head * head)135 __STATIC_INLINE void list_add_tail(struct list_head *new, struct list_head *head)
136 {
137 __list_add(new, head->prev, head);
138 }
139
140 /*
141 * Delete a list entry by making the prev/next entries
142 * point to each other.
143 *
144 * This is only for internal list manipulation where we know
145 * the prev/next entries already!
146 */
__list_del(struct list_head * prev,struct list_head * next)147 __STATIC_INLINE void __list_del(struct list_head * prev, struct list_head * next)
148 {
149 next->prev = prev;
150 prev->next = next;
151 }
152
153 /**
154 * list_del - deletes entry from list.
155 * \param entry: the element to delete from the list.
156 * Note: list_empty() on entry does not return true after this, the entry is
157 * in an undefined state.
158 */
__list_del_entry(struct list_head * entry)159 __STATIC_INLINE void __list_del_entry(struct list_head *entry)
160 {
161 __list_del(entry->prev, entry->next);
162 }
163
list_del(struct list_head * entry)164 __STATIC_INLINE void list_del(struct list_head *entry)
165 {
166 __list_del(entry->prev, entry->next);
167 entry->next = LIST_POISON1;
168 entry->prev = LIST_POISON2;
169 }
170
171 /**
172 * list_replace - replace old entry by new one
173 * \param old : the element to be replaced
174 * \param new : the new element to insert
175 *
176 * If old was empty, it will be overwritten.
177 */
list_replace(struct list_head * old,struct list_head * new)178 __STATIC_INLINE void list_replace(struct list_head *old,
179 struct list_head *new)
180 {
181 new->next = old->next;
182 new->next->prev = new;
183 new->prev = old->prev;
184 new->prev->next = new;
185 }
186
list_replace_init(struct list_head * old,struct list_head * new)187 __STATIC_INLINE void list_replace_init(struct list_head *old,
188 struct list_head *new)
189 {
190 list_replace(old, new);
191 INIT_LIST_HEAD(old);
192 }
193
194 /**
195 * list_del_init - deletes entry from list and reinitialize it.
196 * \param entry: the element to delete from the list.
197 */
list_del_init(struct list_head * entry)198 __STATIC_INLINE void list_del_init(struct list_head *entry)
199 {
200 __list_del_entry(entry);
201 INIT_LIST_HEAD(entry);
202 }
203
204 /**
205 * list_move - delete from one list and add as another's head
206 * \param list: the entry to move
207 * \param head: the head that will precede our entry
208 */
list_move(struct list_head * list,struct list_head * head)209 __STATIC_INLINE void list_move(struct list_head *list, struct list_head *head)
210 {
211 __list_del_entry(list);
212 list_add(list, head);
213 }
214
215 /**
216 * list_move_tail - delete from one list and add as another's tail
217 * \param list: the entry to move
218 * \param head: the head that will follow our entry
219 */
list_move_tail(struct list_head * list,struct list_head * head)220 __STATIC_INLINE void list_move_tail(struct list_head *list,
221 struct list_head *head)
222 {
223 __list_del_entry(list);
224 list_add_tail(list, head);
225 }
226
227 /**
228 * list_is_last - tests whether \param list is the last entry in list \param head
229 * \param list: the entry to test
230 * \param head: the head of the list
231 */
list_is_last(const struct list_head * list,const struct list_head * head)232 __STATIC_INLINE int list_is_last(const struct list_head *list,
233 const struct list_head *head)
234 {
235 return list->next == head;
236 }
237
238 /**
239 * list_empty - tests whether a list is empty
240 * \param head: the list to test.
241 */
list_empty(const struct list_head * head)242 __STATIC_INLINE int list_empty(const struct list_head *head)
243 {
244 return head->next == head;
245 }
246
247 /**
248 * list_empty_careful - tests whether a list is empty and not being modified
249 * \param head: the list to test
250 *
251 * Description:
252 * tests whether a list is empty _and_ checks that no other CPU might be
253 * in the process of modifying either member (next or prev)
254 *
255 * NOTE: using list_empty_careful() without synchronization
256 * can only be safe if the only activity that can happen
257 * to the list entry is list_del_init(). Eg. it cannot be used
258 * if another CPU could re-list_add() it.
259 */
list_empty_careful(const struct list_head * head)260 __STATIC_INLINE int list_empty_careful(const struct list_head *head)
261 {
262 struct list_head *next = head->next;
263 return (next == head) && (next == head->prev);
264 }
265
266 /**
267 * list_rotate_left - rotate the list to the left
268 * \param head: the head of the list
269 */
list_rotate_left(struct list_head * head)270 __STATIC_INLINE void list_rotate_left(struct list_head *head)
271 {
272 struct list_head *first;
273
274 if (!list_empty(head))
275 {
276 first = head->next;
277 list_move_tail(first, head);
278 }
279 }
280
281 /**
282 * list_is_singular - tests whether a list has just one entry.
283 * \param head: the list to test.
284 */
list_is_singular(const struct list_head * head)285 __STATIC_INLINE int list_is_singular(const struct list_head *head)
286 {
287 return !list_empty(head) && (head->next == head->prev);
288 }
289
__list_cut_position(struct list_head * list,struct list_head * head,struct list_head * entry)290 __STATIC_INLINE void __list_cut_position(struct list_head *list,
291 struct list_head *head, struct list_head *entry)
292 {
293 struct list_head *new_first = entry->next;
294 list->next = head->next;
295 list->next->prev = list;
296 list->prev = entry;
297 entry->next = list;
298 head->next = new_first;
299 new_first->prev = head;
300 }
301
302 /**
303 * list_cut_position - cut a list into two
304 * \param list: a new list to add all removed entries
305 * \param head: a list with entries
306 * \param entry: an entry within head, could be the head itself
307 * and if so we won't cut the list
308 *
309 * This helper moves the initial part of head, up to and
310 * including entry, from head to list. You should
311 * pass on entry an element you know is on head. list
312 * should be an empty list or a list you do not care about
313 * losing its data.
314 *
315 */
list_cut_position(struct list_head * list,struct list_head * head,struct list_head * entry)316 __STATIC_INLINE void list_cut_position(struct list_head *list,
317 struct list_head *head, struct list_head *entry)
318 {
319 if (list_empty(head))
320 return;
321 if (list_is_singular(head) &&
322 (head->next != entry && head != entry))
323 return;
324 if (entry == head)
325 INIT_LIST_HEAD(list);
326 else
327 __list_cut_position(list, head, entry);
328 }
329
__list_splice(const struct list_head * list,struct list_head * prev,struct list_head * next)330 __STATIC_INLINE void __list_splice(const struct list_head *list,
331 struct list_head *prev,
332 struct list_head *next)
333 {
334 struct list_head *first = list->next;
335 struct list_head *last = list->prev;
336
337 first->prev = prev;
338 prev->next = first;
339
340 last->next = next;
341 next->prev = last;
342 }
343
344 /**
345 * list_splice - join two lists, this is designed for stacks
346 * \param list: the new list to add.
347 * \param head: the place to add it in the first list.
348 */
list_splice(const struct list_head * list,struct list_head * head)349 __STATIC_INLINE void list_splice(const struct list_head *list,
350 struct list_head *head)
351 {
352 if (!list_empty(list))
353 __list_splice(list, head, head->next);
354 }
355
356 /**
357 * list_splice_tail - join two lists, each list being a queue
358 * \param list: the new list to add.
359 * \param head: the place to add it in the first list.
360 */
list_splice_tail(struct list_head * list,struct list_head * head)361 __STATIC_INLINE void list_splice_tail(struct list_head *list,
362 struct list_head *head)
363 {
364 if (!list_empty(list))
365 __list_splice(list, head->prev, head);
366 }
367
368 /**
369 * list_splice_init - join two lists and reinitialise the emptied list.
370 * \param list: the new list to add.
371 * \param head: the place to add it in the first list.
372 *
373 * The list at 'list' is reinitialised
374 */
list_splice_init(struct list_head * list,struct list_head * head)375 __STATIC_INLINE void list_splice_init(struct list_head *list,
376 struct list_head *head)
377 {
378 if (!list_empty(list))
379 {
380 __list_splice(list, head, head->next);
381 INIT_LIST_HEAD(list);
382 }
383 }
384
385 /**
386 * list_splice_tail_init - join two lists and reinitialise the emptied list
387 * \param list: the new list to add.
388 * \param head: the place to add it in the first list.
389 *
390 * Each of the lists is a queue.
391 * The list at 'list' is reinitialised
392 */
list_splice_tail_init(struct list_head * list,struct list_head * head)393 __STATIC_INLINE void list_splice_tail_init(struct list_head *list,
394 struct list_head *head)
395 {
396 if (!list_empty(list))
397 {
398 __list_splice(list, head->prev, head);
399 INIT_LIST_HEAD(list);
400 }
401 }
402
403 /**
404 * list_entry - get the struct for this entry
405 * \param ptr: the &struct list_head pointer.
406 * \param type: the type of the struct this is embedded in.
407 * \param member: the name of the list_struct within the struct.
408 */
409 #define list_entry(ptr, type, member) \
410 container_of(ptr, type, member)
411
412 /**
413 * list_first_entry - get the first element from a list
414 * \param ptr: the list head to take the element from.
415 * \param type: the type of the struct this is embedded in.
416 * \param member: the name of the list_struct within the struct.
417 *
418 * Note, that list is expected to be not empty.
419 */
420 #define list_first_entry(ptr, type, member) \
421 list_entry((ptr)->next, type, member)
422
423 /**
424 * list_for_each - iterate over a list
425 * \param pos: the &struct list_head to use as a loop cursor.
426 * \param head: the head for your list.
427 */
428 #define list_for_each(pos, head) \
429 for (pos = (head)->next; pos != (head); pos = pos->next)
430
431 /**
432 * __list_for_each - iterate over a list
433 * \param pos: the &struct list_head to use as a loop cursor.
434 * \param head: the head for your list.
435 *
436 * This variant differs from list_for_each() in that it's the
437 * simplest possible list iteration code, no prefetching is done.
438 * Use this for code that knows the list to be very short (empty
439 * or 1 entry) most of the time.
440 */
441 #define __list_for_each(pos, head) \
442 for (pos = (head)->next; pos != (head); pos = pos->next)
443
444 /**
445 * list_for_each_prev - iterate over a list backwards
446 * \param pos: the &struct list_head to use as a loop cursor.
447 * \param head: the head for your list.
448 */
449 #define list_for_each_prev(pos, head) \
450 for (pos = (head)->prev; pos != (head); pos = pos->prev)
451
452 /**
453 * list_for_each_safe - iterate over a list safe against removal of list entry
454 * \param pos: the &struct list_head to use as a loop cursor.
455 * \param n: another &struct list_head to use as temporary storage
456 * \param head: the head for your list.
457 */
458 #define list_for_each_safe(pos, n, head) \
459 for (pos = (head)->next, n = pos->next; pos != (head); \
460 pos = n, n = pos->next)
461
462 /**
463 * list_for_each_prev_safe - iterate over a list backwards safe against removal of list entry
464 * \param pos: the &struct list_head to use as a loop cursor.
465 * \param n: another &struct list_head to use as temporary storage
466 * \param head: the head for your list.
467 */
468 #define list_for_each_prev_safe(pos, n, head) \
469 for (pos = (head)->prev, n = pos->prev; \
470 pos != (head); \
471 pos = n, n = pos->prev)
472
473 /**
474 * list_for_each_entry - iterate over list of given type
475 * \param pos: the type * to use as a loop cursor.
476 * \param head: the head for your list.
477 * \param member: the name of the list_struct within the struct.
478 */
479 #define list_for_each_entry(pos, head, type, member) \
480 for (pos = list_entry((head)->next, type, member); \
481 &pos->member != (head); \
482 pos = list_entry(pos->member.next, type, member))
483
484 /**
485 * list_for_each_entry_reverse - iterate backwards over list of given type.
486 * \param pos: the type * to use as a loop cursor.
487 * \param head: the head for your list.
488 * \param type: the type of the container struct this is embedded in.
489 * \param member: the name of the list_struct within the struct.
490 */
491 #define list_for_each_entry_reverse(pos, head, type, member) \
492 for (pos = list_entry((head)->prev, type, member); \
493 &pos->member != (head); \
494 pos = list_entry(pos->member.prev, type, member))
495
496 /**
497 * list_prepare_entry - prepare a pos entry for use in list_for_each_entry_continue()
498 * \param pos: the type * to use as a start point
499 * \param head: the head of the list
500 * \param type: the type of the container struct this is embedded in.
501 * \param member: the name of the list_struct within the struct.
502 *
503 * Prepares a pos entry for use as a start point in list_for_each_entry_continue().
504 */
505 #define list_prepare_entry(pos, head, type, member) \
506 ((pos) ? : list_entry(head, type, member))
507
508 /**
509 * list_for_each_entry_continue - continue iteration over list of given type
510 * \param pos: the type * to use as a loop cursor.
511 * \param head: the head for your list.
512 * \param type: the type of the container struct this is embedded in.
513 * \param member: the name of the list_struct within the struct.
514 *
515 * Continue to iterate over list of given type, continuing after
516 * the current position.
517 */
518 #define list_for_each_entry_continue(pos, head, type, member) \
519 for (pos = list_entry(pos->member.next, type, member); \
520 &pos->member != (head); \
521 pos = list_entry(pos->member.next, type, member))
522
523 /**
524 * list_for_each_entry_continue_reverse - iterate backwards from the given point
525 * \param pos: the type * to use as a loop cursor.
526 * \param head: the head for your list.
527 * \param type: the type of the container struct this is embedded in.
528 * \param member: the name of the list_struct within the struct.
529 *
530 * Start to iterate over list of given type backwards, continuing after
531 * the current position.
532 */
533 #define list_for_each_entry_continue_reverse(pos, head, type, member) \
534 for (pos = list_entry(pos->member.prev, type, member); \
535 &pos->member != (head); \
536 pos = list_entry(pos->member.prev, type, member))
537
538 /**
539 * list_for_each_entry_from - iterate over list of given type from the current point
540 * \param pos: the type * to use as a loop cursor.
541 * \param head: the head for your list.
542 * \param type: the type of the container struct this is embedded in.
543 * \param member: the name of the list_struct within the struct.
544 *
545 * Iterate over list of given type, continuing from current position.
546 */
547 #define list_for_each_entry_from(pos, head, type, member) \
548 for (; &pos->member != (head); \
549 pos = list_entry(pos->member.next, type, member))
550
551 /**
552 * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
553 * \param pos: the type * to use as a loop cursor.
554 * \param n: another type * to use as temporary storage
555 * \param head: the head for your list.
556 * \param type: the type of the container struct this is embedded in.
557 * \param member: the name of the list_struct within the struct.
558 */
559 #define list_for_each_entry_safe(pos, n, head, type, member) \
560 for (pos = list_entry((head)->next, type, member), \
561 n = list_entry(pos->member.next, type, member); \
562 &pos->member != (head); \
563 pos = n, n = list_entry(n->member.next, type, member))
564
565 /**
566 * list_for_each_entry_safe_continue - continue list iteration safe against removal
567 * \param pos: the type * to use as a loop cursor.
568 * \param n: another type * to use as temporary storage
569 * \param head: the head for your list.
570 * \param type: the type of the container struct this is embedded in.
571 * \param member: the name of the list_struct within the struct.
572 *
573 * Iterate over list of given type, continuing after current point,
574 * safe against removal of list entry.
575 */
576 #define list_for_each_entry_safe_continue(pos, n, head, type, member) \
577 for (pos = list_entry(pos->member.next, type), member), \
578 n = list_entry(pos->member.next, type, member); \
579 &pos->member != (head); \
580 pos = n, n = list_entry(n->member.next, type, member))
581
582 /**
583 * list_for_each_entry_safe_from - iterate over list from current point safe against removal
584 * \param pos: the type * to use as a loop cursor.
585 * \param n: another type * to use as temporary storage
586 * \param head: the head for your list.
587 * \param type: the type of the container struct this is embedded in.
588 * \param member: the name of the list_struct within the struct.
589 *
590 * Iterate over list of given type from current point, safe against
591 * removal of list entry.
592 */
593 #define list_for_each_entry_safe_from(pos, n, head, type, member) \
594 for (n = list_entry(pos->member.next, type, member); \
595 &pos->member != (head); \
596 pos = n, n = list_entry(n->member.next, type, member))
597
598 /**
599 * list_for_each_entry_safe_reverse - iterate backwards over list safe against removal
600 * \param pos: the type * to use as a loop cursor.
601 * \param n: another type * to use as temporary storage
602 * \param head: the head for your list.
603 * \param type: the type of the container struct this is embedded in.
604 * \param member: the name of the list_struct within the struct.
605 *
606 * Iterate backwards over list of given type, safe against removal
607 * of list entry.
608 */
609 #define list_for_each_entry_safe_reverse(pos, n, head, type, member) \
610 for (pos = list_entry((head)->prev, type, member), \
611 n = list_entry(pos->member.prev, type, member); \
612 &pos->member != (head); \
613 pos = n, n = list_entry(n->member.prev, type, member))
614
615 /**
616 * list_safe_reset_next - reset a stale list_for_each_entry_safe loop
617 * \param pos: the loop cursor used in the list_for_each_entry_safe loop
618 * \param n: temporary storage used in list_for_each_entry_safe
619 * \param type: the type of the container struct this is embedded in.
620 * \param member: the name of the list_struct within the struct.
621 *
622 * list_safe_reset_next is not safe to use in general if the list may be
623 * modified concurrently (eg. the lock is dropped in the loop body). An
624 * exception to this is if the cursor element (pos) is pinned in the list,
625 * and list_safe_reset_next is called after re-taking the lock and before
626 * completing the current iteration of the loop body.
627 */
628 #define list_safe_reset_next(pos, n, type, member) \
629 n = list_entry(pos->member.next, type, member)
630
631 #endif /* _LNX_LIST_H_ */
632
633