SDR (Software Defined Radio) » OsmoSDR

#ifndef _LINUX_LLIST_H

#define _LINUX_LLIST_H

#include <stddef.h>

#ifndef inline

#define inline __inline__

#endif

static inline void prefetch(const void *x) {;}

/**

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

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

/*

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

 * under normal circumstances, used to verify that nobody uses

 * non-initialized llist entries.

 */

#define LLIST_POISON1  ((void *) 0x00100100)

#define LLIST_POISON2  ((void *) 0x00200200)

/*

 * Simple doubly linked llist implementation.

 *

 * Some of the internal functions ("__xxx") are useful when

 * manipulating whole llists 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 llist_head {

	struct llist_head *next, *prev;

};

#define LLIST_HEAD_INIT(name) { &(name), &(name) }

#define LLIST_HEAD(name) \

	struct llist_head name = LLIST_HEAD_INIT(name)

#define INIT_LLIST_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 llist manipulation where we know

 * the prev/next entries already!

 */

static inline void __llist_add(struct llist_head *_new,

			      struct llist_head *prev,

			      struct llist_head *next)

{

	next->prev = _new;

	_new->next = next;

	_new->prev = prev;

	prev->next = _new;

}

/**

 * llist_add - add a new entry

 * @new: new entry to be added

 * @head: llist head to add it after

 *

 * Insert a new entry after the specified head.

 * This is good for implementing stacks.

 */

static inline void llist_add(struct llist_head *_new, struct llist_head *head)

{

	__llist_add(_new, head, head->next);

}

/**

 * llist_add_tail - add a new entry

 * @new: new entry to be added

 * @head: llist head to add it before

 *

 * Insert a new entry before the specified head.

 * This is useful for implementing queues.

 */

static inline void llist_add_tail(struct llist_head *_new, struct llist_head *head)

{

	__llist_add(_new, head->prev, head);

}

/*

 * Delete a llist entry by making the prev/next entries

 * point to each other.

 *

 * This is only for internal llist manipulation where we know

 * the prev/next entries already!

 */

static inline void __llist_del(struct llist_head * prev, struct llist_head * next)

{

	next->prev = prev;

	prev->next = next;

}

/**

 * llist_del - deletes entry from llist.

 * @entry: the element to delete from the llist.

 * Note: llist_empty on entry does not return true after this, the entry is

 * in an undefined state.

 */

static inline void llist_del(struct llist_head *entry)

{

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

	entry->next = (struct llist_head *)LLIST_POISON1;

	entry->prev = (struct llist_head *)LLIST_POISON2;

}

/**

 * llist_del_init - deletes entry from llist and reinitialize it.

 * @entry: the element to delete from the llist.

 */

static inline void llist_del_init(struct llist_head *entry)

{

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

	INIT_LLIST_HEAD(entry); 

}

/**

 * llist_move - delete from one llist and add as another's head

 * @llist: the entry to move

 * @head: the head that will precede our entry

 */

static inline void llist_move(struct llist_head *llist, struct llist_head *head)

{

        __llist_del(llist->prev, llist->next);

        llist_add(llist, head);

}

/**

 * llist_move_tail - delete from one llist and add as another's tail

 * @llist: the entry to move

 * @head: the head that will follow our entry

 */

static inline void llist_move_tail(struct llist_head *llist,

				  struct llist_head *head)

{

        __llist_del(llist->prev, llist->next);

        llist_add_tail(llist, head);

}

/**

 * llist_empty - tests whether a llist is empty

 * @head: the llist to test.

 */

static inline int llist_empty(const struct llist_head *head)

{

	return head->next == head;

}

static inline void __llist_splice(struct llist_head *llist,

				 struct llist_head *head)

{

	struct llist_head *first = llist->next;

	struct llist_head *last = llist->prev;

	struct llist_head *at = head->next;

	first->prev = head;

	head->next = first;

	last->next = at;

	at->prev = last;

}

/**

 * llist_splice - join two llists

 * @llist: the new llist to add.

 * @head: the place to add it in the first llist.

 */

static inline void llist_splice(struct llist_head *llist, struct llist_head *head)

{

	if (!llist_empty(llist))

		__llist_splice(llist, head);

}

/**

 * llist_splice_init - join two llists and reinitialise the emptied llist.

 * @llist: the new llist to add.

 * @head: the place to add it in the first llist.

 *

 * The llist at @llist is reinitialised

 */

static inline void llist_splice_init(struct llist_head *llist,

				    struct llist_head *head)

{

	if (!llist_empty(llist)) {

		__llist_splice(llist, head);

		INIT_LLIST_HEAD(llist);

	}

}

/**

 * llist_entry - get the struct for this entry

 * @ptr:	the &struct llist_head pointer.

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

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

 */

#define llist_entry(ptr, type, member) \

	container_of(ptr, type, member)

/**

 * llist_for_each	-	iterate over a llist

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

 * @head:	the head for your llist.

 */

#define llist_for_each(pos, head) \

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

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

/**

 * __llist_for_each	-	iterate over a llist

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

 * @head:	the head for your llist.

 *

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

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

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

 * or 1 entry) most of the time.

 */

#define __llist_for_each(pos, head) \

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

/**

 * llist_for_each_prev	-	iterate over a llist backwards

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

 * @head:	the head for your llist.

 */

#define llist_for_each_prev(pos, head) \

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

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

/**

 * llist_for_each_safe	-	iterate over a llist safe against removal of llist entry

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

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

 * @head:	the head for your llist.

 */

#define llist_for_each_safe(pos, n, head) \

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

		pos = n, n = pos->next)

/**

 * llist_for_each_entry	-	iterate over llist of given type

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

 * @head:	the head for your llist.

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

 */

#define llist_for_each_entry(pos, head, member)				\

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

		     prefetch(pos->member.next);			\

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

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

		     prefetch(pos->member.next))

/**

 * llist_for_each_entry_reverse - iterate backwards over llist of given type.

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

 * @head:	the head for your llist.

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

 */

#define llist_for_each_entry_reverse(pos, head, member)			\

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

		     prefetch(pos->member.prev);			\

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

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

		     prefetch(pos->member.prev))

/**

 * llist_for_each_entry_continue -	iterate over llist of given type

 *			continuing after existing point

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

 * @head:	the head for your llist.

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

 */

#define llist_for_each_entry_continue(pos, head, member) 		\

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

		     prefetch(pos->member.next);			\

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

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

		     prefetch(pos->member.next))

/**

 * llist_for_each_entry_safe - iterate over llist of given type safe against removal of llist entry

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

 * @n:		another type * to use as temporary storage

 * @head:	the head for your llist.

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

 */

#define llist_for_each_entry_safe(pos, n, head, member)			\

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

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

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

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

/**

 * llist_for_each_rcu	-	iterate over an rcu-protected llist

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

 * @head:	the head for your llist.

 */

#define llist_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 __llist_for_each_rcu(pos, head) \

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

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

/**

 * llist_for_each_safe_rcu	-	iterate over an rcu-protected llist safe

 *					against removal of llist entry

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

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

 * @head:	the head for your llist.

 */

#define llist_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)

/**

 * llist_for_each_entry_rcu	-	iterate over rcu llist of given type

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

 * @head:	the head for your llist.

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

 */

#define llist_for_each_entry_rcu(pos, head, member)			\

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

		     prefetch(pos->member.next);			\

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

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

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

		     prefetch(pos->member.next))

/**

 * llist_for_each_continue_rcu	-	iterate over an rcu-protected llist 

 *			continuing after existing point.

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

 * @head:	the head for your llist.

 */

#define llist_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))

#endif