5 #ifdef __compiler_offsetof
6 #define offsetof(TYPE,MEMBER) __compiler_offsetof(TYPE,MEMBER)
8 #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
11 #define container_of(ptr, type, member) ({ \
12 const typeof( ((type *)0)->member ) *__mptr = (ptr); \
13 (type *)( (char *)__mptr - offsetof(type,member) );})
16 * Simple doubly linked list implementation.
18 * Some of the internal functions ("__xxx") are useful when
19 * manipulating whole lists rather than single entries, as
20 * sometimes we already know the next/prev entries and we can
21 * generate better code by using them directly rather than
22 * using the generic single-entry routines.
26 struct list_head *next, *prev;
29 #define LIST_HEAD_INIT(name) { &(name), &(name) }
31 #define INIT_LIST_HEAD(ptr) do { \
32 (ptr)->next = (ptr); (ptr)->prev = (ptr); \
36 * Insert a new entry between two known consecutive entries.
38 * This is only for internal list manipulation where we know
39 * the prev/next entries already!
41 static inline void __list_add(struct list_head *new,
42 struct list_head *prev,
43 struct list_head *next)
52 * list_add - add a new entry
53 * @new: new entry to be added
54 * @head: list head to add it after
56 * Insert a new entry after the specified head.
57 * This is good for implementing stacks.
59 static inline void list_add(struct list_head *new, struct list_head *head)
61 __list_add(new, head, head->next);
64 static inline void list_add_tail(struct list_head *new, struct list_head *head)
66 __list_add(new, head->prev, head);
70 * Delete a list entry by making the prev/next entries
71 * point to each other.
73 * This is only for internal list manipulation where we know
74 * the prev/next entries already!
76 static inline void __list_del(struct list_head * prev, struct list_head * next)
83 * list_del - deletes entry from list.
84 * @entry: the element to delete from the list.
85 * Note: list_empty on entry does not return true after this, the entry is
86 * in an undefined state.
88 static inline void list_del(struct list_head *entry)
90 __list_del(entry->prev, entry->next);
96 * list_empty - tests whether a list is empty
97 * @head: the list to test.
99 static inline int list_empty(const struct list_head *head)
101 return head->next == head;
105 * list_entry - get the struct for this entry
106 * @ptr: the &struct list_head pointer.
107 * @type: the type of the struct this is embedded in.
108 * @member: the name of the list_struct within the struct.
110 #define list_entry(ptr, type, member) \
111 container_of(ptr, type, member)
114 * list_for_each - iterate over a list
115 * @pos: the &struct list_head to use as a loop counter.
116 * @head: the head for your list.
118 #define list_for_each(pos, head) \
119 for (pos = (head)->next; pos != (head); pos = pos->next)
122 * list_for_each_safe - iterate over a list safe against removal of list entry
123 * @pos: the &struct list_head to use as a loop counter.
124 * @n: another &struct list_head to use as temporary storage
125 * @head: the head for your list.
127 #define list_for_each_safe(pos, n, head) \
128 for (pos = (head)->next, n = pos->next; pos != (head); \
129 pos = n, n = pos->next)