You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
252 lines
7.2 KiB
252 lines
7.2 KiB
11 years ago
|
#ifndef _LINUX_LIST_H
|
||
|
#define _LINUX_LIST_H
|
||
|
|
||
|
/*
|
||
|
* Simple doubly linked list implementation.
|
||
|
*
|
||
|
* Some of the internal functions ("__xxx") are useful when
|
||
|
* manipulating whole lists rather than single entries, as
|
||
|
* sometimes we already know the next/prev entries and we can
|
||
|
* generate better code by using them directly rather than
|
||
|
* using the generic single-entry routines.
|
||
|
*/
|
||
|
|
||
|
struct list_head {
|
||
|
struct list_head *next, *prev;
|
||
|
};
|
||
|
|
||
|
#define LIST_HEAD_INIT(name) { &(name), &(name) }
|
||
|
|
||
|
#define LIST_HEAD(name) \
|
||
|
struct list_head name = LIST_HEAD_INIT(name)
|
||
|
|
||
|
#define INIT_LIST_HEAD(ptr) do { \
|
||
|
(ptr)->next = (ptr); (ptr)->prev = (ptr); \
|
||
|
} while (0)
|
||
|
|
||
|
/*
|
||
|
* Insert a new entry between two known consecutive entries.
|
||
|
*
|
||
|
* This is only for internal list manipulation where we know
|
||
|
* the prev/next entries already!
|
||
|
*/
|
||
|
static __inline void __list_add(struct list_head *lnew,
|
||
|
struct list_head *prev,
|
||
|
struct list_head *next)
|
||
|
{
|
||
|
next->prev = lnew;
|
||
|
lnew->next = next;
|
||
|
lnew->prev = prev;
|
||
|
prev->next = lnew;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_add - add a new entry
|
||
|
* @new: new entry to be added
|
||
|
* @head: list head to add it after
|
||
|
*
|
||
|
* Insert a new entry after the specified head.
|
||
|
* This is good for implementing stacks.
|
||
|
*/
|
||
|
static __inline void list_add(struct list_head *lnew, struct list_head *head)
|
||
|
{
|
||
|
__list_add(lnew, head, head->next);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_add_tail - add a new entry
|
||
|
* @new: new entry to be added
|
||
|
* @head: list head to add it before
|
||
|
*
|
||
|
* Insert a new entry before the specified head.
|
||
|
* This is useful for implementing queues.
|
||
|
*/
|
||
|
static __inline void list_add_tail(struct list_head *lnew, struct list_head *head)
|
||
|
{
|
||
|
__list_add(lnew, head->prev, head);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Delete a list entry by making the prev/next entries
|
||
|
* point to each other.
|
||
|
*
|
||
|
* This is only for internal list manipulation where we know
|
||
|
* the prev/next entries already!
|
||
|
*/
|
||
|
static __inline void __list_del(struct list_head *prev, struct list_head *next)
|
||
|
{
|
||
|
next->prev = prev;
|
||
|
prev->next = next;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_del - deletes entry from list.
|
||
|
* @entry: the element to delete from the list.
|
||
|
* Note: list_empty on entry does not return true after this, the entry is in an undefined state.
|
||
|
*/
|
||
|
static __inline void list_del(struct list_head *entry)
|
||
|
{
|
||
|
__list_del(entry->prev, entry->next);
|
||
|
entry->next = (struct list_head *) 0;
|
||
|
entry->prev = (struct list_head *) 0;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_del_init - deletes entry from list and reinitialize it.
|
||
|
* @entry: the element to delete from the list.
|
||
|
*/
|
||
|
static __inline void list_del_init(struct list_head *entry)
|
||
|
{
|
||
|
__list_del(entry->prev, entry->next);
|
||
|
INIT_LIST_HEAD(entry);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_move - delete from one list and add as another's head
|
||
|
* @list: the entry to move
|
||
|
* @head: the head that will precede our entry
|
||
|
*/
|
||
|
static __inline void list_move(struct list_head *list, struct list_head *head)
|
||
|
{
|
||
|
__list_del(list->prev, list->next);
|
||
|
list_add(list, head);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_move_tail - delete from one list and add as another's tail
|
||
|
* @list: the entry to move
|
||
|
* @head: the head that will follow our entry
|
||
|
*/
|
||
|
static __inline void list_move_tail(struct list_head *list,
|
||
|
struct list_head *head)
|
||
|
{
|
||
|
__list_del(list->prev, list->next);
|
||
|
list_add_tail(list, head);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_empty - tests whether a list is empty
|
||
|
* @head: the list to test.
|
||
|
*/
|
||
|
static __inline int list_empty(struct list_head *head)
|
||
|
{
|
||
|
return head->next == head;
|
||
|
}
|
||
|
|
||
|
static __inline void __list_splice(struct list_head *list,
|
||
|
struct list_head *head)
|
||
|
{
|
||
|
struct list_head *first = list->next;
|
||
|
struct list_head *last = list->prev;
|
||
|
struct list_head *at = head->next;
|
||
|
|
||
|
first->prev = head;
|
||
|
head->next = first;
|
||
|
|
||
|
last->next = at;
|
||
|
at->prev = last;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_splice - join two lists
|
||
|
* @list: the new list to add.
|
||
|
* @head: the place to add it in the first list.
|
||
|
*/
|
||
|
static __inline void list_splice(struct list_head *list, struct list_head *head)
|
||
|
{
|
||
|
if (!list_empty(list))
|
||
|
__list_splice(list, head);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_splice_init - join two lists and reinitialise the emptied list.
|
||
|
* @list: the new list to add.
|
||
|
* @head: the place to add it in the first list.
|
||
|
*
|
||
|
* The list at @list is reinitialised
|
||
|
*/
|
||
|
static __inline void list_splice_init(struct list_head *list,
|
||
|
struct list_head *head)
|
||
|
{
|
||
|
if (!list_empty(list)) {
|
||
|
__list_splice(list, head);
|
||
|
INIT_LIST_HEAD(list);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* list_entry - get the struct for this entry
|
||
|
* @ptr: the &struct list_head pointer.
|
||
|
* @type: the type of the struct this is embedded in.
|
||
|
* @member: the name of the list_struct within the struct.
|
||
|
*/
|
||
|
#define list_entry(ptr, type, member) \
|
||
|
((type *)((char *)(ptr)-(unsigned long)(&((type *)0)->member)))
|
||
|
|
||
|
/**
|
||
|
* list_for_each - iterate over a list
|
||
|
* @pos: the &struct list_head to use as a loop counter.
|
||
|
* @head: the head for your list.
|
||
|
*/
|
||
|
#define list_for_each(pos, head) \
|
||
|
for (pos = (head)->next; pos != (head); \
|
||
|
pos = pos->next)
|
||
|
/**
|
||
|
* list_for_each_prev - iterate over a list backwards
|
||
|
* @pos: the &struct list_head to use as a loop counter.
|
||
|
* @head: the head for your list.
|
||
|
*/
|
||
|
#define list_for_each_prev(pos, head) \
|
||
|
for (pos = (head)->prev; pos != (head); \
|
||
|
pos = pos->prev)
|
||
|
|
||
|
/**
|
||
|
* list_for_each_safe - iterate over a list safe against removal of list entry
|
||
|
* @pos: the &struct list_head to use as a loop counter.
|
||
|
* @n: another &struct list_head to use as temporary storage
|
||
|
* @head: the head for your list.
|
||
|
*/
|
||
|
#define list_for_each_safe(pos, n, head) \
|
||
|
for (pos = (head)->next, n = pos->next; pos != (head); \
|
||
|
pos = n, n = pos->next)
|
||
|
|
||
|
/**
|
||
|
* list_for_each_entry - iterate over list of given type
|
||
|
* @pos: the type * to use as a loop counter.
|
||
|
* @head: the head for your list.
|
||
|
* @member: the name of the list_struct within the struct.
|
||
|
*/
|
||
|
#define list_for_each_entry(pos, head, member, tpos) \
|
||
|
for (pos = list_entry((head)->next, tpos, member); \
|
||
|
&pos->member != (head); \
|
||
|
pos = list_entry(pos->member.next, tpos, member))
|
||
|
|
||
|
/**
|
||
|
* list_for_each_entry_safe - iterate over list of given type safe against removal of list entry
|
||
|
* @pos: the type * to use as a loop counter.
|
||
|
* @n: another type * to use as temporary storage
|
||
|
* @head: the head for your list.
|
||
|
* @member: the name of the list_struct within the struct.
|
||
|
*/
|
||
|
#define list_for_each_entry_safe(pos, n, head, member, tpos, tn) \
|
||
|
for (pos = list_entry((head)->next, tpos, member), \
|
||
|
n = list_entry(pos->member.next, tpos, member); \
|
||
|
&pos->member != (head); \
|
||
|
pos = n, n = list_entry(n->member.next, tn, member))
|
||
|
|
||
|
/**
|
||
|
* list_for_each_entry_continue - iterate over list of given type
|
||
|
* continuing after existing point
|
||
|
* @pos: the type * to use as a loop counter.
|
||
|
* @head: the head for your list.
|
||
|
* @member: the name of the list_struct within the struct.
|
||
|
*/
|
||
|
#define list_for_each_entry_continue(pos, head, member, tpos) \
|
||
|
for (pos = list_entry(pos->member.next, tpos, member), \
|
||
|
prefetch(pos->member.next); \
|
||
|
&pos->member != (head); \
|
||
|
pos = list_entry(pos->member.next, tpos, member), \
|
||
|
prefetch(pos->member.next))
|
||
|
|
||
|
#endif
|