#ifndef _LINUX_LIST_H

#define _LINUX_LIST_H

#undef offsetof

#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)

/**

 * container_of - cast a member of a structure out to the containing structure

 *

 * @ptr:	the pointer to the member.

 * @type:	the type of the container struct this is embedded in.

 * @member:	the name of the member within the struct.

 *

 */

#define container_of(ptr, type, member) ({			\

        const typeof( ((type *)0)->member ) *__mptr = (ptr);	\

        (type *)( (char *)__mptr - offsetof(type,member) );})

/*

 * Check at compile time that something is of a particular type.

 * Always evaluates to 1 so you may use it easily in comparisons.

 */

#define typecheck(type,x) \

({	type __dummy; \

	typeof(x) __dummy2; \

	(void)(&__dummy == &__dummy2); \

	1; \

})

#define prefetch(x)		((void)0)

/* empty define to make this work in userspace -HW */

#define smp_wmb()

/*

 * These are non-NULL pointers that will result in page faults

 * under normal circumstances, used to verify that nobody uses

 * non-initialized list entries.

 */

#define LIST_POISON1  ((void *) 0x00100100)

#define LIST_POISON2  ((void *) 0x00200200)

/*

 * 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 *new,

			      struct list_head *prev,

			      struct list_head *next)

{

	next->prev = new;

	new->next = next;

	new->prev = prev;

	prev->next = new;

}

/**

 * 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 *new, struct list_head *head)

{

	__list_add(new, 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 *new, struct list_head *head)

{

	__list_add(new, head->prev, head);

}

/*

 * 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_rcu(struct list_head * new,

		struct list_head * prev, struct list_head * next)

{

	new->next = next;

	new->prev = prev;

	smp_wmb();

	next->prev = new;

	prev->next = new;

}

/**

 * list_add_rcu - add a new entry to rcu-protected list

 * @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.

 *

 * The caller must take whatever precautions are necessary

 * (such as holding appropriate locks) to avoid racing

 * with another list-mutation primitive, such as list_add_rcu()

 * or list_del_rcu(), running on this same list.

 * However, it is perfectly legal to run concurrently with

 * the _rcu list-traversal primitives, such as

 * list_for_each_entry_rcu().

 */

static inline void list_add_rcu(struct list_head *new, struct list_head *head)

{

	__list_add_rcu(new, head, head->next);

}

/**

 * list_add_tail_rcu - add a new entry to rcu-protected list

 * @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.

 *

 * The caller must take whatever precautions are necessary

 * (such as holding appropriate locks) to avoid racing

 * with another list-mutation primitive, such as list_add_tail_rcu()

 * or list_del_rcu(), running on this same list.

 * However, it is perfectly legal to run concurrently with

 * the _rcu list-traversal primitives, such as

 * list_for_each_entry_rcu().

 */

static inline void list_add_tail_rcu(struct list_head *new,

					struct list_head *head)

{

	__list_add_rcu(new, 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 = LIST_POISON1;

	entry->prev = LIST_POISON2;

}

/**

 * list_del_rcu - deletes entry from list without re-initialization

 * @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. It is useful for RCU based

 * lockfree traversal.

 *

 * In particular, it means that we can not poison the forward

 * pointers that may still be used for walking the list.

 *

 * The caller must take whatever precautions are necessary

 * (such as holding appropriate locks) to avoid racing

 * with another list-mutation primitive, such as list_del_rcu()

 * or list_add_rcu(), running on this same list.

 * However, it is perfectly legal to run concurrently with

 * the _rcu list-traversal primitives, such as

 * list_for_each_entry_rcu().

 *

 * Note that the caller is not permitted to immediately free

 * the newly deleted entry.  Instead, either synchronize_kernel()

 * or call_rcu() must be used to defer freeing until an RCU

 * grace period has elapsed.

 */

static inline void list_del_rcu(struct list_head *entry)

{

	__list_del(entry->prev, entry->next);

	entry->prev = LIST_POISON2;

}

/**

 * 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(const struct list_head *head)

{

	return head->next == head;

}

/**

 * list_empty_careful - tests whether a list is

 * empty _and_ checks that no other CPU might be

 * in the process of still modifying either member

 *

 * NOTE: using list_empty_careful() without synchronization

 * can only be safe if the only activity that can happen

 * to the list entry is list_del_init(). Eg. it cannot be used

 * if another CPU could re-list_add() it.

 *

 * @head: the list to test.

 */

static inline int list_empty_careful(const struct list_head *head)

{

	struct list_head *next = head->next;

	return (next == head) && (next == head->prev);

}

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) \

	container_of(ptr, type, 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, prefetch(pos->next); pos != (head); \

        	pos = pos->next, prefetch(pos->next))

/**

 * __list_for_each	-	iterate over a list

 * @pos:	the &struct list_head to use as a loop counter.

 * @head:	the head for your list.

 *

 * This variant differs from list_for_each() in that it's the

 * simplest possible list iteration code, no prefetching is done.

 * Use this for code that knows the list to be very short (empty

 * or 1 entry) most of the time.

 */

#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, prefetch(pos->prev); pos != (head); \

        	pos = pos->prev, prefetch(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)				\

	for (pos = list_entry((head)->next, typeof(*pos), member),	\

		     prefetch(pos->member.next);			\

	     &pos->member != (head); 					\

	     pos = list_entry(pos->member.next, typeof(*pos), member),	\

		     prefetch(pos->member.next))

/**

 * list_for_each_entry_reverse - iterate backwards 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_reverse(pos, head, member)			\

	for (pos = list_entry((head)->prev, typeof(*pos), member),	\

		     prefetch(pos->member.prev);			\

	     &pos->member != (head); 					\

	     pos = list_entry(pos->member.prev, typeof(*pos), member),	\

		     prefetch(pos->member.prev))

/**

 * list_prepare_entry - prepare a pos entry for use as a start point in

 *			list_for_each_entry_continue

 * @pos:	the type * to use as a start point

 * @head:	the head of the list

 * @member:	the name of the list_struct within the struct.

 */

#define list_prepare_entry(pos, head, member) \

	((pos) ? : list_entry(head, typeof(*pos), 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) 		\

	for (pos = list_entry(pos->member.next, typeof(*pos), member),	\

		     prefetch(pos->member.next);			\

	     &pos->member != (head);					\

	     pos = list_entry(pos->member.next, typeof(*pos), member),	\

		     prefetch(pos->member.next))

/**

 * 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)			\

	for (pos = list_entry((head)->next, typeof(*pos), member),	\

		n = list_entry(pos->member.next, typeof(*pos), member);	\

	     &pos->member != (head); 					\

	     pos = n, n = list_entry(n->member.next, typeof(*n), member))

/**

 * list_for_each_rcu	-	iterate over an rcu-protected list

 * @pos:	the &struct list_head to use as a loop counter.

 * @head:	the head for your list.

 *

 * This list-traversal primitive may safely run concurrently with

 * the _rcu list-mutation primitives such as list_add_rcu()

 * as long as the traversal is guarded by rcu_read_lock().

 */

#define list_for_each_rcu(pos, head) \

	for (pos = (head)->next, prefetch(pos->next); pos != (head); \

        	pos = pos->next, ({ smp_read_barrier_depends(); 0;}), prefetch(pos->next))

#define __list_for_each_rcu(pos, head) \

	for (pos = (head)->next; pos != (head); \

        	pos = pos->next, ({ smp_read_barrier_depends(); 0;}))

/**

 * list_for_each_safe_rcu	-	iterate over an rcu-protected 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.

 *

 * This list-traversal primitive may safely run concurrently with

 * the _rcu list-mutation primitives such as list_add_rcu()

 * as long as the traversal is guarded by rcu_read_lock().

 */

#define list_for_each_safe_rcu(pos, n, head) \

	for (pos = (head)->next, n = pos->next; pos != (head); \

		pos = n, ({ smp_read_barrier_depends(); 0;}), n = pos->next)

/**

 * list_for_each_entry_rcu	-	iterate over rcu 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.

 *

 * This list-traversal primitive may safely run concurrently with

 * the _rcu list-mutation primitives such as list_add_rcu()

 * as long as the traversal is guarded by rcu_read_lock().

 */

#define list_for_each_entry_rcu(pos, head, member)			\

	for (pos = list_entry((head)->next, typeof(*pos), member),	\

		     prefetch(pos->member.next);			\

	     &pos->member != (head); 					\

	     pos = list_entry(pos->member.next, typeof(*pos), member),	\

		     ({ smp_read_barrier_depends(); 0;}),		\

		     prefetch(pos->member.next))

/**

 * list_for_each_continue_rcu	-	iterate over an rcu-protected list

 *			continuing after existing point.

 * @pos:	the &struct list_head to use as a loop counter.

 * @head:	the head for your list.

 *

 * This list-traversal primitive may safely run concurrently with

 * the _rcu list-mutation primitives such as list_add_rcu()

 * as long as the traversal is guarded by rcu_read_lock().

 */

#define list_for_each_continue_rcu(pos, head) \

	for ((pos) = (pos)->next, prefetch((pos)->next); (pos) != (head); \

        	(pos) = (pos)->next, ({ smp_read_barrier_depends(); 0;}), prefetch((pos)->next))

/*

 * Double linked lists with a single pointer list head.

 * Mostly useful for hash tables where the two pointer list head is

 * too wasteful.

 * You lose the ability to access the tail in O(1).

 */

struct hlist_head {

	struct hlist_node *first;

};

struct hlist_node {

	struct hlist_node *next, **pprev;

};

#define HLIST_HEAD_INIT { .first = NULL }

#define HLIST_HEAD(name) struct hlist_head name = {  .first = NULL }

#define INIT_HLIST_HEAD(ptr) ((ptr)->first = NULL)

#define INIT_HLIST_NODE(ptr) ((ptr)->next = NULL, (ptr)->pprev = NULL)

static inline int hlist_unhashed(const struct hlist_node *h)

{

	return !h->pprev;

}

static inline int hlist_empty(const struct hlist_head *h)

{

	return !h->first;

}

static inline void __hlist_del(struct hlist_node *n)

{

	struct hlist_node *next = n->next;

	struct hlist_node **pprev = n->pprev;

	*pprev = next;

	if (next)

		next->pprev = pprev;

}

static inline void hlist_del(struct hlist_node *n)

{

	__hlist_del(n);

	n->next = LIST_POISON1;

	n->pprev = LIST_POISON2;

}

/**

 * hlist_del_rcu - deletes entry from hash list without re-initialization

 * @n: the element to delete from the hash list.

 *

 * Note: list_unhashed() on entry does not return true after this,

 * the entry is in an undefined state. It is useful for RCU based

 * lockfree traversal.

 *

 * In particular, it means that we can not poison the forward

 * pointers that may still be used for walking the hash list.

 *

 * The caller must take whatever precautions are necessary

 * (such as holding appropriate locks) to avoid racing

 * with another list-mutation primitive, such as hlist_add_head_rcu()

 * or hlist_del_rcu(), running on this same list.

 * However, it is perfectly legal to run concurrently with

 * the _rcu list-traversal primitives, such as

 * hlist_for_each_entry().

 */

static inline void hlist_del_rcu(struct hlist_node *n)

{

	__hlist_del(n);

	n->pprev = LIST_POISON2;

}

static inline void hlist_del_init(struct hlist_node *n)

{

	if (n->pprev)  {

		__hlist_del(n);

		INIT_HLIST_NODE(n);

	}

}

#define hlist_del_rcu_init hlist_del_init

static inline void hlist_add_head(struct hlist_node *n, struct hlist_head *h)

{

	struct hlist_node *first = h->first;

	n->next = first;

	if (first)

		first->pprev = &n->next;

	h->first = n;

	n->pprev = &h->first;

}

/**

 * hlist_add_head_rcu - adds the specified element to the specified hlist,

 * while permitting racing traversals.

 * @n: the element to add to the hash list.

 * @h: the list to add to.

 *

 * The caller must take whatever precautions are necessary

 * (such as holding appropriate locks) to avoid racing

 * with another list-mutation primitive, such as hlist_add_head_rcu()

 * or hlist_del_rcu(), running on this same list.

 * However, it is perfectly legal to run concurrently with

 * the _rcu list-traversal primitives, such as

 * hlist_for_each_entry(), but only if smp_read_barrier_depends()

 * is used to prevent memory-consistency problems on Alpha CPUs.

 * Regardless of the type of CPU, the list-traversal primitive

 * must be guarded by rcu_read_lock().

 *

 * OK, so why don't we have an hlist_for_each_entry_rcu()???

 */

static inline void hlist_add_head_rcu(struct hlist_node *n,

					struct hlist_head *h)

{

	struct hlist_node *first = h->first;

	n->next = first;

	n->pprev = &h->first;

	smp_wmb();

	if (first)

		first->pprev = &n->next;

	h->first = n;

}

/* next must be != NULL */

static inline void hlist_add_before(struct hlist_node *n,

					struct hlist_node *next)

{

	n->pprev = next->pprev;

	n->next = next;

	next->pprev = &n->next;

	*(n->pprev) = n;

}

static inline void hlist_add_after(struct hlist_node *n,

					struct hlist_node *next)

{

	next->next = n->next;

	n->next = next;

	next->pprev = &n->next;

	if(next->next)

		next->next->pprev  = &next->next;

}

#define hlist_entry(ptr, type, member) container_of(ptr,type,member)

#define hlist_for_each(pos, head) \

	for (pos = (head)->first; pos && ({ prefetch(pos->next); 1; }); \

	     pos = pos->next)

#define hlist_for_each_safe(pos, n, head) \

	for (pos = (head)->first; pos && ({ n = pos->next; 1; }); \

	     pos = n)

/**

 * hlist_for_each_entry	- iterate over list of given type

 * @tpos:	the type * to use as a loop counter.

 * @pos:	the &struct hlist_node to use as a loop counter.

 * @head:	the head for your list.

 * @member:	the name of the hlist_node within the struct.

 */

#define hlist_for_each_entry(tpos, pos, head, member)			 \

	for (pos = (head)->first;					 \

	     pos && ({ prefetch(pos->next); 1;}) &&			 \

		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \

	     pos = pos->next)

/**

 * hlist_for_each_entry_continue - iterate over a hlist continuing after existing point

 * @tpos:	the type * to use as a loop counter.

 * @pos:	the &struct hlist_node to use as a loop counter.

 * @member:	the name of the hlist_node within the struct.

 */

#define hlist_for_each_entry_continue(tpos, pos, member)		 \

	for (pos = (pos)->next;						 \

	     pos && ({ prefetch(pos->next); 1;}) &&			 \

		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \

	     pos = pos->next)

/**

 * hlist_for_each_entry_from - iterate over a hlist continuing from existing point

 * @tpos:	the type * to use as a loop counter.

 * @pos:	the &struct hlist_node to use as a loop counter.

 * @member:	the name of the hlist_node within the struct.

 */

#define hlist_for_each_entry_from(tpos, pos, member)			 \

	for (; pos && ({ prefetch(pos->next); 1;}) &&			 \

		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \

	     pos = pos->next)

/**

 * hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry

 * @tpos:	the type * to use as a loop counter.

 * @pos:	the &struct hlist_node to use as a loop counter.

 * @n:		another &struct hlist_node to use as temporary storage

 * @head:	the head for your list.

 * @member:	the name of the hlist_node within the struct.

 */

#define hlist_for_each_entry_safe(tpos, pos, n, head, member) 		 \

	for (pos = (head)->first;					 \

	     pos && ({ n = pos->next; 1; }) && 				 \

		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \

	     pos = n)

/**

 * hlist_for_each_entry_rcu - iterate over rcu list of given type

 * @pos:	the type * to use as a loop counter.

 * @pos:	the &struct hlist_node to use as a loop counter.

 * @head:	the head for your list.

 * @member:	the name of the hlist_node within the struct.

 *

 * This list-traversal primitive may safely run concurrently with

 * the _rcu list-mutation primitives such as hlist_add_rcu()

 * as long as the traversal is guarded by rcu_read_lock().

 */

#define hlist_for_each_entry_rcu(tpos, pos, head, member)		 \

	for (pos = (head)->first;					 \

	     pos && ({ prefetch(pos->next); 1;}) &&			 \

		({ tpos = hlist_entry(pos, typeof(*tpos), member); 1;}); \

	     pos = pos->next, ({ smp_read_barrier_depends(); 0; }) )

#endif