1 /*
2  *	klist.h - Some generic list helpers, extending struct list_head a bit.
3  *
4  *	Implementations are found in lib/klist.c
5  *
6  *
7  *	Copyright (C) 2005 Patrick Mochel
8  *
9  *	This file is rleased under the GPL v2.
10  */
11 
12 #ifndef _LINUX_KLIST_H
13 #define _LINUX_KLIST_H
14 
15 #include <linux/spinlock.h>
16 #include <linux/kref.h>
17 #include <linux/list.h>
18 
19 struct klist_node;
20 struct klist {
21 	spinlock_t		k_lock;
22 	struct list_head	k_list;
23 	void			(*get)(struct klist_node *);
24 	void			(*put)(struct klist_node *);
25 } __attribute__ ((aligned (sizeof(void *))));
26 
27 #define KLIST_INIT(_name, _get, _put)					\
28 	{ .k_lock	= __SPIN_LOCK_UNLOCKED(_name.k_lock),		\
29 	  .k_list	= LIST_HEAD_INIT(_name.k_list),			\
30 	  .get		= _get,						\
31 	  .put		= _put, }
32 
33 #define DEFINE_KLIST(_name, _get, _put)					\
34 	struct klist _name = KLIST_INIT(_name, _get, _put)
35 
36 extern void klist_init(struct klist *k, void (*get)(struct klist_node *),
37 		       void (*put)(struct klist_node *));
38 
39 struct klist_node {
40 	void			*n_klist;	/* never access directly */
41 	struct list_head	n_node;
42 	struct kref		n_ref;
43 };
44 
45 extern void klist_add_tail(struct klist_node *n, struct klist *k);
46 extern void klist_add_head(struct klist_node *n, struct klist *k);
47 extern void klist_add_after(struct klist_node *n, struct klist_node *pos);
48 extern void klist_add_before(struct klist_node *n, struct klist_node *pos);
49 
50 extern void klist_del(struct klist_node *n);
51 extern void klist_remove(struct klist_node *n);
52 
53 extern int klist_node_attached(struct klist_node *n);
54 
55 
56 struct klist_iter {
57 	struct klist		*i_klist;
58 	struct klist_node	*i_cur;
59 };
60 
61 
62 extern void klist_iter_init(struct klist *k, struct klist_iter *i);
63 extern void klist_iter_init_node(struct klist *k, struct klist_iter *i,
64 				 struct klist_node *n);
65 extern void klist_iter_exit(struct klist_iter *i);
66 extern struct klist_node *klist_next(struct klist_iter *i);
67 
68 #endif
69