1/* SPDX-License-Identifier: GPL-2.0 */
2struct list {
3	struct list *next, *prev;
4};
5
6static inline void
7list_init(struct list *list)
8{
9	list->next = list;
10	list->prev = list;
11}
12
13static inline int
14list_empty(struct list *list)
15{
16	return list->next == list;
17}
18
19static inline void
20list_insert(struct list *link, struct list *new_link)
21{
22	new_link->prev		= link->prev;
23	new_link->next		= link;
24	new_link->prev->next	= new_link;
25	new_link->next->prev	= new_link;
26}
27
28static inline void
29list_append(struct list *list, struct list *new_link)
30{
31	list_insert((struct list *)list, new_link);
32}
33
34static inline void
35list_prepend(struct list *list, struct list *new_link)
36{
37	list_insert(list->next, new_link);
38}
39
40static inline void
41list_remove(struct list *link)
42{
43	link->prev->next = link->next;
44	link->next->prev = link->prev;
45}
46
47#define list_entry(link, type, member) \
48	((type *)((char *)(link)-(unsigned long)(&((type *)0)->member)))
49
50#define list_head(list, type, member)		\
51	list_entry((list)->next, type, member)
52
53#define list_tail(list, type, member)		\
54	list_entry((list)->prev, type, member)
55
56#define list_next(elm, member)					\
57	list_entry((elm)->member.next, typeof(*elm), member)
58
59#define list_for_each_entry(pos, list, member)			\
60	for (pos = list_head(list, typeof(*pos), member);	\
61	     &pos->member != (list);				\
62	     pos = list_next(pos, member))
63
64