1 /*
2 * Copyright (c) 2010 Isilon Systems, Inc.
3 * Copyright (c) 2010 iX Systems, Inc.
4 * Copyright (c) 2010 Panasas, Inc.
5 * Copyright (c) 2013-2016 Mellanox Technologies, Ltd.
6 * Copyright (c) 2015-2020 François Tigeot <ftigeot@wolfpond.org>
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice unmodified, this list of conditions, and the following
14 * disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30 #ifndef _LINUX_LIST_H_
31 #define _LINUX_LIST_H_
32
33 #include <linux/types.h>
34 #include <linux/stddef.h>
35 #include <linux/poison.h>
36 #include <linux/kernel.h>
37
38 #include <sys/queue.h>
39
40 #define prefetch(x)
41
42 struct list_head {
43 struct list_head *next;
44 struct list_head *prev;
45 };
46
47 #define LIST_HEAD_INIT(name) { .prev = &(name), .next = &(name) }
48
49 #define DRM_LIST_HEAD(name) \
50 struct list_head name = LIST_HEAD_INIT(name)
51
52 static inline void
INIT_LIST_HEAD(struct list_head * list)53 INIT_LIST_HEAD(struct list_head *list)
54 {
55
56 list->next = list->prev = list;
57 }
58
59 static inline struct list_head *
list_first(const struct list_head * head)60 list_first(const struct list_head *head)
61 {
62 return head->next;
63 }
64
65 static inline struct list_head *
list_last(const struct list_head * head)66 list_last(const struct list_head *head)
67 {
68 return head->prev;
69 }
70
71 static inline int
list_empty(const struct list_head * head)72 list_empty(const struct list_head *head)
73 {
74 return (head->next == head);
75 }
76
77 static inline int
list_empty_careful(const struct list_head * head)78 list_empty_careful(const struct list_head *head)
79 {
80 return (head == head->next) && (head == head->prev);
81 }
82
83 static inline void
__list_del(struct list_head * prev,struct list_head * next)84 __list_del(struct list_head *prev, struct list_head *next)
85 {
86 next->prev = prev;
87 WRITE_ONCE(prev->next, next);
88 }
89
90 static inline void
__list_del_entry(struct list_head * entry)91 __list_del_entry(struct list_head *entry)
92 {
93 __list_del(entry->prev, entry->next);
94 }
95
96 static inline void
list_del(struct list_head * entry)97 list_del(struct list_head *entry)
98 {
99
100 entry->next->prev = entry->prev;
101 entry->prev->next = entry->next;
102 }
103
list_replace(struct list_head * old,struct list_head * new)104 static inline void list_replace(struct list_head *old,
105 struct list_head *new)
106 {
107 new->next = old->next;
108 new->next->prev = new;
109 new->prev = old->prev;
110 new->prev->next = new;
111 }
112
list_replace_init(struct list_head * old,struct list_head * new)113 static inline void list_replace_init(struct list_head *old,
114 struct list_head *new)
115 {
116 list_replace(old, new);
117 INIT_LIST_HEAD(old);
118 }
119
120 static inline void
_list_add(struct list_head * new,struct list_head * prev,struct list_head * next)121 _list_add(struct list_head *new, struct list_head *prev,
122 struct list_head *next)
123 {
124
125 next->prev = new;
126 new->next = next;
127 new->prev = prev;
128 prev->next = new;
129 }
130
131 static inline void
list_del_init(struct list_head * entry)132 list_del_init(struct list_head *entry)
133 {
134
135 list_del(entry);
136 INIT_LIST_HEAD(entry);
137 }
138
139 #define list_entry(ptr, type, field) container_of(ptr, type, field)
140
141 #define list_first_entry(ptr, type, member) \
142 list_entry((ptr)->next, type, member)
143
144 #define list_first_entry_or_null(ptr, type, member) \
145 (list_empty(ptr) ? NULL: list_first_entry(ptr, type, member))
146
147 #define list_last_entry(ptr, type, field) \
148 list_entry(list_last((ptr)), type, field)
149
150 #define list_next_entry(ptr, member) \
151 list_entry(((ptr)->member.next), typeof(*(ptr)), member)
152
153 #define list_safe_reset_next(ptr, n, member) \
154 (n) = list_next_entry(ptr, member)
155
156 #define list_prev_entry(ptr, member) \
157 list_entry(((ptr)->member.prev), typeof(*(ptr)), member)
158
159 #define list_for_each(p, head) \
160 for (p = (head)->next; p != (head); p = p->next)
161
162 #define list_for_each_safe(p, n, head) \
163 for (p = (head)->next, n = p->next; p != (head); p = n, n = p->next)
164
165 #define list_for_each_entry(p, h, field) \
166 for (p = list_entry((h)->next, typeof(*p), field); &p->field != (h); \
167 p = list_entry(p->field.next, typeof(*p), field))
168
169 #define list_for_each_entry_safe(p, n, h, field) \
170 for (p = list_entry((h)->next, typeof(*p), field), \
171 n = list_entry(p->field.next, typeof(*p), field); &p->field != (h);\
172 p = n, n = list_entry(n->field.next, typeof(*n), field))
173
174 #define list_for_each_entry_from(p, h, field) \
175 for ( ; &(p)->field != (h); \
176 p = list_entry((p)->field.next, typeof(*p), field))
177
178 #define list_for_each_entry_continue(p, h, field) \
179 for (p = list_next_entry((p), field); &p->field != (h); \
180 p = list_next_entry((p), field))
181
182 #define list_for_each_entry_continue_reverse(pos, head, member) \
183 for (pos = list_entry(pos->member.prev, __typeof(*pos), member); \
184 &pos->member != (head); \
185 pos = list_entry(pos->member.prev, __typeof(*pos), member))
186
187 #define list_for_each_entry_safe_from(pos, n, head, member) \
188 for (n = list_entry(pos->member.next, typeof(*pos), member); \
189 &pos->member != (head); \
190 pos = n, n = list_entry(n->member.next, typeof(*n), member))
191
192 #define list_for_each_entry_reverse(p, h, field) \
193 for (p = list_entry((h)->prev, typeof(*p), field); &p->field != (h); \
194 p = list_entry(p->field.prev, typeof(*p), field))
195
196 #define list_for_each_entry_safe_reverse(p, n, h, field) \
197 for (p = list_entry((h)->prev, typeof(*p), field), \
198 n = list_entry((p)->field.prev, typeof(*p), field); &(p)->field != (h); \
199 p = n, n = list_entry(n->field.prev, typeof(*n), field))
200
201 #define list_for_each_prev(p, h) for (p = (h)->prev; p != (h); p = p->prev)
202
203 static inline void
list_add(struct list_head * new,struct list_head * head)204 list_add(struct list_head *new, struct list_head *head)
205 {
206
207 _list_add(new, head, head->next);
208 }
209
210 static inline void
list_add_tail(struct list_head * new,struct list_head * head)211 list_add_tail(struct list_head *new, struct list_head *head)
212 {
213
214 _list_add(new, head->prev, head);
215 }
216
217 static inline void
list_move(struct list_head * list,struct list_head * head)218 list_move(struct list_head *list, struct list_head *head)
219 {
220
221 list_del(list);
222 list_add(list, head);
223 }
224
225 static inline void
list_move_tail(struct list_head * entry,struct list_head * head)226 list_move_tail(struct list_head *entry, struct list_head *head)
227 {
228
229 list_del(entry);
230 list_add_tail(entry, head);
231 }
232
233 static inline void
_list_splice(const struct list_head * list,struct list_head * prev,struct list_head * next)234 _list_splice(const struct list_head *list, struct list_head *prev,
235 struct list_head *next)
236 {
237 struct list_head *first;
238 struct list_head *last;
239
240 if (list_empty(list))
241 return;
242 first = list->next;
243 last = list->prev;
244 first->prev = prev;
245 prev->next = first;
246 last->next = next;
247 next->prev = last;
248 }
249
250 static inline void
list_splice(const struct list_head * list,struct list_head * head)251 list_splice(const struct list_head *list, struct list_head *head)
252 {
253
254 _list_splice(list, head, head->next);
255 }
256
257 static inline void
list_splice_tail(struct list_head * list,struct list_head * head)258 list_splice_tail(struct list_head *list, struct list_head *head)
259 {
260
261 _list_splice(list, head->prev, head);
262 }
263
264 static inline void
list_splice_init(struct list_head * list,struct list_head * head)265 list_splice_init(struct list_head *list, struct list_head *head)
266 {
267
268 _list_splice(list, head, head->next);
269 INIT_LIST_HEAD(list);
270 }
271
272 static inline void
list_splice_tail_init(struct list_head * list,struct list_head * head)273 list_splice_tail_init(struct list_head *list, struct list_head *head)
274 {
275
276 _list_splice(list, head->prev, head);
277 INIT_LIST_HEAD(list);
278 }
279
280 #define LINUX_LIST_HEAD(name) struct list_head name = { &(name), &(name) }
281
282
283 struct hlist_head {
284 struct hlist_node *first;
285 };
286
287 struct hlist_node {
288 struct hlist_node *next, **pprev;
289 };
290
291 #define HLIST_HEAD_INIT { }
292 #define HLIST_HEAD(name) struct hlist_head name = HLIST_HEAD_INIT
293 #define INIT_HLIST_HEAD(head) (head)->first = NULL
294 #define INIT_HLIST_NODE(node) \
295 do { \
296 (node)->next = NULL; \
297 (node)->pprev = NULL; \
298 } while (0)
299
300 static inline int
hlist_unhashed(const struct hlist_node * h)301 hlist_unhashed(const struct hlist_node *h)
302 {
303
304 return !h->pprev;
305 }
306
307 static inline int
hlist_empty(const struct hlist_head * h)308 hlist_empty(const struct hlist_head *h)
309 {
310
311 return !h->first;
312 }
313
314 static inline void
hlist_del(struct hlist_node * n)315 hlist_del(struct hlist_node *n)
316 {
317
318 if (n->next)
319 n->next->pprev = n->pprev;
320 *n->pprev = n->next;
321 }
322
323 static inline void
hlist_del_init(struct hlist_node * n)324 hlist_del_init(struct hlist_node *n)
325 {
326
327 if (hlist_unhashed(n))
328 return;
329 hlist_del(n);
330 INIT_HLIST_NODE(n);
331 }
332
333 static inline void
hlist_add_head(struct hlist_node * n,struct hlist_head * h)334 hlist_add_head(struct hlist_node *n, struct hlist_head *h)
335 {
336
337 n->next = h->first;
338 if (h->first)
339 h->first->pprev = &n->next;
340 h->first = n;
341 n->pprev = &h->first;
342 }
343
344 static inline void
hlist_add_before(struct hlist_node * n,struct hlist_node * next)345 hlist_add_before(struct hlist_node *n, struct hlist_node *next)
346 {
347
348 n->pprev = next->pprev;
349 n->next = next;
350 next->pprev = &n->next;
351 *(n->pprev) = n;
352 }
353
354 static inline void
hlist_add_after(struct hlist_node * n,struct hlist_node * next)355 hlist_add_after(struct hlist_node *n, struct hlist_node *next)
356 {
357
358 next->next = n->next;
359 n->next = next;
360 next->pprev = &n->next;
361 if (next->next)
362 next->next->pprev = &next->next;
363 }
364
365 static inline void
hlist_move_list(struct hlist_head * old,struct hlist_head * new)366 hlist_move_list(struct hlist_head *old, struct hlist_head *new)
367 {
368
369 new->first = old->first;
370 if (new->first)
371 new->first->pprev = &new->first;
372 old->first = NULL;
373 }
374
375 /**
376 * list_is_singular - tests whether a list has just one entry.
377 * @head: the list to test.
378 */
list_is_singular(const struct list_head * head)379 static inline int list_is_singular(const struct list_head *head)
380 {
381 return !list_empty(head) && (head->next == head->prev);
382 }
383
__list_cut_position(struct list_head * list,struct list_head * head,struct list_head * entry)384 static inline void __list_cut_position(struct list_head *list,
385 struct list_head *head, struct list_head *entry)
386 {
387 struct list_head *new_first = entry->next;
388 list->next = head->next;
389 list->next->prev = list;
390 list->prev = entry;
391 entry->next = list;
392 head->next = new_first;
393 new_first->prev = head;
394 }
395
396 /**
397 * list_cut_position - cut a list into two
398 * @list: a new list to add all removed entries
399 * @head: a list with entries
400 * @entry: an entry within head, could be the head itself
401 * and if so we won't cut the list
402 *
403 * This helper moves the initial part of @head, up to and
404 * including @entry, from @head to @list. You should
405 * pass on @entry an element you know is on @head. @list
406 * should be an empty list or a list you do not care about
407 * losing its data.
408 *
409 */
list_cut_position(struct list_head * list,struct list_head * head,struct list_head * entry)410 static inline void list_cut_position(struct list_head *list,
411 struct list_head *head, struct list_head *entry)
412 {
413 if (list_empty(head))
414 return;
415 if (list_is_singular(head) &&
416 (head->next != entry && head != entry))
417 return;
418 if (entry == head)
419 INIT_LIST_HEAD(list);
420 else
421 __list_cut_position(list, head, entry);
422 }
423
424 /**
425 * list_is_last - tests whether @list is the last entry in list @head
426 * @list: the entry to test
427 * @head: the head of the list
428 */
list_is_last(const struct list_head * list,const struct list_head * head)429 static inline int list_is_last(const struct list_head *list,
430 const struct list_head *head)
431 {
432 return list->next == head;
433 }
434
435 #define hlist_entry(ptr, type, field) container_of(ptr, type, field)
436
437 #define hlist_for_each(p, head) \
438 for (p = (head)->first; p; p = p->next)
439
440 #define hlist_for_each_safe(p, n, head) \
441 for (p = (head)->first; p && ({ n = p->next; 1; }); p = n)
442
443 #define hlist_entry_safe(ptr, type, member) \
444 (ptr) ? hlist_entry(ptr, type, member) : NULL
445
446 #define hlist_for_each_entry(pos, head, member) \
447 for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member);\
448 pos; \
449 pos = hlist_entry_safe((pos)->member.next, typeof(*(pos)), member))
450
451 #define hlist_for_each_entry_continue(tp, p, field) \
452 for (p = (p)->next; \
453 p ? (tp = hlist_entry(p, typeof(*tp), field)): NULL; p = p->next)
454
455 #define hlist_for_each_entry_from(tp, p, field) \
456 for (; p ? (tp = hlist_entry(p, typeof(*tp), field)): NULL; p = p->next)
457
458 #define hlist_for_each_entry_safe(pos, n, head, member) \
459 for (pos = hlist_entry_safe((head)->first, typeof(*(pos)), member); \
460 (pos) && ({ n = (pos)->member.next; 1; }); \
461 pos = hlist_entry_safe(n, typeof(*(pos)), member))
462
463 void drm_list_sort(void *priv, struct list_head *head, int (*cmp)(void *priv,
464 struct list_head *a, struct list_head *b));
465
466 #define hlist_add_head_rcu(n, h) hlist_add_head(n, h)
467
468 #define hlist_del_init_rcu(n) hlist_del_init(n)
469
470 #endif /* _LINUX_LIST_H_ */
471