/**
* klist_init - Initialize a klist structure.
* @k: The klist we're initializing.
+ * @get: The get function for the embedding object (NULL if none)
+ * @put: The put function for the embedding object (NULL if none)
+ *
+ * Initialises the klist structure. If the klist_node structures are
+ * going to be embedded in refcounted objects (necessary for safe
+ * deletion) then the get/put arguments are used to initialise
+ * functions that take and release references on the embedding
+ * objects.
*/
-void klist_init(struct klist * k)
+void klist_init(struct klist * k, void (*get)(struct klist_node *),
+ void (*put)(struct klist_node *))
{
INIT_LIST_HEAD(&k->k_list);
spin_lock_init(&k->k_lock);
+ k->get = get;
+ k->put = put;
}
EXPORT_SYMBOL_GPL(klist_init);
init_completion(&n->n_removed);
kref_init(&n->n_ref);
n->n_klist = k;
+ if (k->get)
+ k->get(n);
}
/**
* klist_add_head - Initialize a klist_node and add it to front.
- * @k: klist it's going on.
* @n: node we're adding.
+ * @k: klist it's going on.
*/
-void klist_add_head(struct klist * k, struct klist_node * n)
+void klist_add_head(struct klist_node * n, struct klist * k)
{
klist_node_init(k, n);
add_head(k, n);
/**
* klist_add_tail - Initialize a klist_node and add it to back.
- * @k: klist it's going on.
* @n: node we're adding.
+ * @k: klist it's going on.
*/
-void klist_add_tail(struct klist * k, struct klist_node * n)
+void klist_add_tail(struct klist_node * n, struct klist * k)
{
klist_node_init(k, n);
add_tail(k, n);
static void klist_release(struct kref * kref)
{
struct klist_node * n = container_of(kref, struct klist_node, n_ref);
+
list_del(&n->n_node);
complete(&n->n_removed);
n->n_klist = NULL;
void klist_del(struct klist_node * n)
{
struct klist * k = n->n_klist;
+ void (*put)(struct klist_node *) = k->put;
spin_lock(&k->k_lock);
- klist_dec_and_del(n);
+ if (!klist_dec_and_del(n))
+ put = NULL;
spin_unlock(&k->k_lock);
+ if (put)
+ put(n);
}
EXPORT_SYMBOL_GPL(klist_del);
void klist_remove(struct klist_node * n)
{
- struct klist * k = n->n_klist;
- spin_lock(&k->k_lock);
- klist_dec_and_del(n);
- spin_unlock(&k->k_lock);
+ klist_del(n);
wait_for_completion(&n->n_removed);
}
i->i_klist = k;
i->i_head = &k->k_list;
i->i_cur = n;
+ if (n)
+ kref_get(&n->n_ref);
}
EXPORT_SYMBOL_GPL(klist_iter_init_node);
struct klist_node * klist_next(struct klist_iter * i)
{
struct list_head * next;
+ struct klist_node * lnode = i->i_cur;
struct klist_node * knode = NULL;
+ void (*put)(struct klist_node *) = i->i_klist->put;
spin_lock(&i->i_klist->k_lock);
- if (i->i_cur) {
- next = i->i_cur->n_node.next;
- klist_dec_and_del(i->i_cur);
+ if (lnode) {
+ next = lnode->n_node.next;
+ if (!klist_dec_and_del(lnode))
+ put = NULL;
} else
next = i->i_head->next;
}
i->i_cur = knode;
spin_unlock(&i->i_klist->k_lock);
+ if (put && lnode)
+ put(lnode);
return knode;
}