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-rw-r--r--include/linux/klist.h30
-rw-r--r--lib/klist.c206
2 files changed, 100 insertions, 136 deletions
diff --git a/include/linux/klist.h b/include/linux/klist.h
index b49385f13419..06c338ef7f1b 100644
--- a/include/linux/klist.h
+++ b/include/linux/klist.h
@@ -34,38 +34,38 @@ struct klist {
34#define DEFINE_KLIST(_name, _get, _put) \ 34#define DEFINE_KLIST(_name, _get, _put) \
35 struct klist _name = KLIST_INIT(_name, _get, _put) 35 struct klist _name = KLIST_INIT(_name, _get, _put)
36 36
37extern void klist_init(struct klist * k, void (*get)(struct klist_node *), 37extern void klist_init(struct klist *k, void (*get)(struct klist_node *),
38 void (*put)(struct klist_node *)); 38 void (*put)(struct klist_node *));
39 39
40struct klist_node { 40struct klist_node {
41 struct klist * n_klist; 41 struct klist *n_klist;
42 struct list_head n_node; 42 struct list_head n_node;
43 struct kref n_ref; 43 struct kref n_ref;
44 struct completion n_removed; 44 struct completion n_removed;
45}; 45};
46 46
47extern void klist_add_tail(struct klist_node * n, struct klist * k); 47extern void klist_add_tail(struct klist_node *n, struct klist *k);
48extern void klist_add_head(struct klist_node * n, struct klist * k); 48extern void klist_add_head(struct klist_node *n, struct klist *k);
49extern void klist_add_after(struct klist_node *n, struct klist_node *pos); 49extern void klist_add_after(struct klist_node *n, struct klist_node *pos);
50extern void klist_add_before(struct klist_node *n, struct klist_node *pos); 50extern void klist_add_before(struct klist_node *n, struct klist_node *pos);
51 51
52extern void klist_del(struct klist_node * n); 52extern void klist_del(struct klist_node *n);
53extern void klist_remove(struct klist_node * n); 53extern void klist_remove(struct klist_node *n);
54 54
55extern int klist_node_attached(struct klist_node * n); 55extern int klist_node_attached(struct klist_node *n);
56 56
57 57
58struct klist_iter { 58struct klist_iter {
59 struct klist * i_klist; 59 struct klist *i_klist;
60 struct list_head * i_head; 60 struct list_head *i_head;
61 struct klist_node * i_cur; 61 struct klist_node *i_cur;
62}; 62};
63 63
64 64
65extern void klist_iter_init(struct klist * k, struct klist_iter * i); 65extern void klist_iter_init(struct klist *k, struct klist_iter *i);
66extern void klist_iter_init_node(struct klist * k, struct klist_iter * i, 66extern void klist_iter_init_node(struct klist *k, struct klist_iter *i,
67 struct klist_node * n); 67 struct klist_node *n);
68extern void klist_iter_exit(struct klist_iter * i); 68extern void klist_iter_exit(struct klist_iter *i);
69extern struct klist_node * klist_next(struct klist_iter * i); 69extern struct klist_node *klist_next(struct klist_iter *i);
70 70
71#endif 71#endif
diff --git a/lib/klist.c b/lib/klist.c
index ebba9488046e..cca37f96faa2 100644
--- a/lib/klist.c
+++ b/lib/klist.c
@@ -1,38 +1,37 @@
1/* 1/*
2 * klist.c - Routines for manipulating klists. 2 * klist.c - Routines for manipulating klists.
3 * 3 *
4 * Copyright (C) 2005 Patrick Mochel
4 * 5 *
5 * This klist interface provides a couple of structures that wrap around 6 * This file is released under the GPL v2.
6 * struct list_head to provide explicit list "head" (struct klist) and
7 * list "node" (struct klist_node) objects. For struct klist, a spinlock
8 * is included that protects access to the actual list itself. struct
9 * klist_node provides a pointer to the klist that owns it and a kref
10 * reference count that indicates the number of current users of that node
11 * in the list.
12 * 7 *
13 * The entire point is to provide an interface for iterating over a list 8 * This klist interface provides a couple of structures that wrap around
14 * that is safe and allows for modification of the list during the 9 * struct list_head to provide explicit list "head" (struct klist) and list
15 * iteration (e.g. insertion and removal), including modification of the 10 * "node" (struct klist_node) objects. For struct klist, a spinlock is
16 * current node on the list. 11 * included that protects access to the actual list itself. struct
12 * klist_node provides a pointer to the klist that owns it and a kref
13 * reference count that indicates the number of current users of that node
14 * in the list.
17 * 15 *
18 * It works using a 3rd object type - struct klist_iter - that is declared 16 * The entire point is to provide an interface for iterating over a list
19 * and initialized before an iteration. klist_next() is used to acquire the 17 * that is safe and allows for modification of the list during the
20 * next element in the list. It returns NULL if there are no more items. 18 * iteration (e.g. insertion and removal), including modification of the
21 * Internally, that routine takes the klist's lock, decrements the reference 19 * current node on the list.
22 * count of the previous klist_node and increments the count of the next
23 * klist_node. It then drops the lock and returns.
24 * 20 *
25 * There are primitives for adding and removing nodes to/from a klist. 21 * It works using a 3rd object type - struct klist_iter - that is declared
26 * When deleting, klist_del() will simply decrement the reference count. 22 * and initialized before an iteration. klist_next() is used to acquire the
27 * Only when the count goes to 0 is the node removed from the list. 23 * next element in the list. It returns NULL if there are no more items.
28 * klist_remove() will try to delete the node from the list and block 24 * Internally, that routine takes the klist's lock, decrements the
29 * until it is actually removed. This is useful for objects (like devices) 25 * reference count of the previous klist_node and increments the count of
30 * that have been removed from the system and must be freed (but must wait 26 * the next klist_node. It then drops the lock and returns.
31 * until all accessors have finished).
32 * 27 *
33 * Copyright (C) 2005 Patrick Mochel 28 * There are primitives for adding and removing nodes to/from a klist.
34 * 29 * When deleting, klist_del() will simply decrement the reference count.
35 * This file is released under the GPL v2. 30 * Only when the count goes to 0 is the node removed from the list.
31 * klist_remove() will try to delete the node from the list and block until
32 * it is actually removed. This is useful for objects (like devices) that
33 * have been removed from the system and must be freed (but must wait until
34 * all accessors have finished).
36 */ 35 */
37 36
38#include <linux/klist.h> 37#include <linux/klist.h>
@@ -40,10 +39,10 @@
40 39
41 40
42/** 41/**
43 * klist_init - Initialize a klist structure. 42 * klist_init - Initialize a klist structure.
44 * @k: The klist we're initializing. 43 * @k: The klist we're initializing.
45 * @get: The get function for the embedding object (NULL if none) 44 * @get: The get function for the embedding object (NULL if none)
46 * @put: The put function for the embedding object (NULL if none) 45 * @put: The put function for the embedding object (NULL if none)
47 * 46 *
48 * Initialises the klist structure. If the klist_node structures are 47 * Initialises the klist structure. If the klist_node structures are
49 * going to be embedded in refcounted objects (necessary for safe 48 * going to be embedded in refcounted objects (necessary for safe
@@ -51,8 +50,7 @@
51 * functions that take and release references on the embedding 50 * functions that take and release references on the embedding
52 * objects. 51 * objects.
53 */ 52 */
54 53void klist_init(struct klist *k, void (*get)(struct klist_node *),
55void klist_init(struct klist * k, void (*get)(struct klist_node *),
56 void (*put)(struct klist_node *)) 54 void (*put)(struct klist_node *))
57{ 55{
58 INIT_LIST_HEAD(&k->k_list); 56 INIT_LIST_HEAD(&k->k_list);
@@ -60,26 +58,23 @@ void klist_init(struct klist * k, void (*get)(struct klist_node *),
60 k->get = get; 58 k->get = get;
61 k->put = put; 59 k->put = put;
62} 60}
63
64EXPORT_SYMBOL_GPL(klist_init); 61EXPORT_SYMBOL_GPL(klist_init);
65 62
66 63static void add_head(struct klist *k, struct klist_node *n)
67static void add_head(struct klist * k, struct klist_node * n)
68{ 64{
69 spin_lock(&k->k_lock); 65 spin_lock(&k->k_lock);
70 list_add(&n->n_node, &k->k_list); 66 list_add(&n->n_node, &k->k_list);
71 spin_unlock(&k->k_lock); 67 spin_unlock(&k->k_lock);
72} 68}
73 69
74static void add_tail(struct klist * k, struct klist_node * n) 70static void add_tail(struct klist *k, struct klist_node *n)
75{ 71{
76 spin_lock(&k->k_lock); 72 spin_lock(&k->k_lock);
77 list_add_tail(&n->n_node, &k->k_list); 73 list_add_tail(&n->n_node, &k->k_list);
78 spin_unlock(&k->k_lock); 74 spin_unlock(&k->k_lock);
79} 75}
80 76
81 77static void klist_node_init(struct klist *k, struct klist_node *n)
82static void klist_node_init(struct klist * k, struct klist_node * n)
83{ 78{
84 INIT_LIST_HEAD(&n->n_node); 79 INIT_LIST_HEAD(&n->n_node);
85 init_completion(&n->n_removed); 80 init_completion(&n->n_removed);
@@ -89,37 +84,30 @@ static void klist_node_init(struct klist * k, struct klist_node * n)
89 k->get(n); 84 k->get(n);
90} 85}
91 86
92
93/** 87/**
94 * klist_add_head - Initialize a klist_node and add it to front. 88 * klist_add_head - Initialize a klist_node and add it to front.
95 * @n: node we're adding. 89 * @n: node we're adding.
96 * @k: klist it's going on. 90 * @k: klist it's going on.