5 * Copied from include/linux/...
9 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
12 * container_of - cast a member of a structure out to the containing structure
13 * @ptr: the pointer to the member.
14 * @type: the type of the container struct this is embedded in.
15 * @member: the name of the member within the struct.
18 #define container_of(ptr, type, member) ({ \
19 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
20 (type *)( (char *)__mptr - offsetof(type,member) );})
24 struct list_head *next, *prev;
28 #define LIST_HEAD_INIT(name) { &(name), &(name) }
30 #define LIST_HEAD(name) \
31 struct list_head name = LIST_HEAD_INIT(name)
34 * list_entry - get the struct for this entry
35 * @ptr: the &struct list_head pointer.
36 * @type: the type of the struct this is embedded in.
37 * @member: the name of the list_head within the struct.
39 #define list_entry(ptr, type, member) \
40 container_of(ptr, type, member)
43 * list_for_each_entry - iterate over list of given type
44 * @pos: the type * to use as a loop cursor.
45 * @head: the head for your list.
46 * @member: the name of the list_head within the struct.
48 #define list_for_each_entry(pos, head, member) \
49 for (pos = list_entry((head)->next, typeof(*pos), member); \
50 &pos->member != (head); \
51 pos = list_entry(pos->member.next, typeof(*pos), member))
54 * list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
55 * @pos: the type * to use as a loop cursor.
56 * @n: another type * to use as temporary storage
57 * @head: the head for your list.
58 * @member: the name of the list_head within the struct.
60 #define list_for_each_entry_safe(pos, n, head, member) \
61 for (pos = list_entry((head)->next, typeof(*pos), member), \
62 n = list_entry(pos->member.next, typeof(*pos), member); \
63 &pos->member != (head); \
64 pos = n, n = list_entry(n->member.next, typeof(*n), member))
67 * list_empty - tests whether a list is empty
68 * @head: the list to test.
70 static inline int list_empty(const struct list_head *head)
72 return head->next == head;
76 * Insert a new entry between two known consecutive entries.
78 * This is only for internal list manipulation where we know
79 * the prev/next entries already!
81 static inline void __list_add(struct list_head *_new,
82 struct list_head *prev,
83 struct list_head *next)
92 * list_add_tail - add a new entry
93 * @new: new entry to be added
94 * @head: list head to add it before
96 * Insert a new entry before the specified head.
97 * This is useful for implementing queues.
99 static inline void list_add_tail(struct list_head *_new, struct list_head *head)
101 __list_add(_new, head->prev, head);
105 * Delete a list entry by making the prev/next entries
106 * point to each other.
108 * This is only for internal list manipulation where we know
109 * the prev/next entries already!
111 static inline void __list_del(struct list_head *prev, struct list_head *next)
117 #define LIST_POISON1 ((void *) 0x00100100)
118 #define LIST_POISON2 ((void *) 0x00200200)
120 * list_del - deletes entry from list.
121 * @entry: the element to delete from the list.
122 * Note: list_empty() on entry does not return true after this, the entry is
123 * in an undefined state.
125 static inline void list_del(struct list_head *entry)
127 __list_del(entry->prev, entry->next);
128 entry->next = (struct list_head*)LIST_POISON1;
129 entry->prev = (struct list_head*)LIST_POISON2;