1 /* SPDX-License-Identifier: GPL-2.0 */
2 struct list {
3 	struct list *next, *prev;
4 };
5 
6 static inline void
list_init(struct list * list)7 list_init(struct list *list)
8 {
9 	list->next = list;
10 	list->prev = list;
11 }
12 
13 static inline int
list_empty(struct list * list)14 list_empty(struct list *list)
15 {
16 	return list->next == list;
17 }
18 
19 static inline void
list_insert(struct list * link,struct list * new_link)20 list_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 
28 static inline void
list_append(struct list * list,struct list * new_link)29 list_append(struct list *list, struct list *new_link)
30 {
31 	list_insert((struct list *)list, new_link);
32 }
33 
34 static inline void
list_prepend(struct list * list,struct list * new_link)35 list_prepend(struct list *list, struct list *new_link)
36 {
37 	list_insert(list->next, new_link);
38 }
39 
40 static inline void
list_remove(struct list * link)41 list_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