*
*/
+/** \file list.h doubly linked list implementation */
+
#include <stddef.h> /* offsetof */
+/** get the struct this entry is embedded in */
#define container_of(ptr, type, member) ({ \
const typeof( ((type *)0)->member ) *__mptr = (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 list entries.
+/**
+ * Non-NULL pointers that will result in page faults under normal
+ * circumstances, used to verify that nobody uses non-initialized list entries.
+ * Used for poisoning the \a next pointer of struct list_head.
*/
#define LIST_POISON1 ((void *) 0x00100100)
+/** Non-null pointer, used for poisoning the \a prev pointer of struct
+ * list_head
+ */
#define LIST_POISON2 ((void *) 0x00200200)
-/**
- * Simple doubly linked list implementation.
- *
+/** Simple doubly linked list implementation. */
+struct list_head {
+ /** pointer to the next list entry */
+ struct list_head *next;
+ /** pointer to the previous list entry */
+ struct list_head *prev;
+};
+
+/** must be called before using any other list functions */
+#define INIT_LIST_HEAD(ptr) do { \
+ (ptr)->next = (ptr); (ptr)->prev = (ptr); \
+} while (0)
+
+
+/*
* 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 INIT_LIST_HEAD(ptr) do { \
- (ptr)->next = (ptr); (ptr)->prev = (ptr); \
-} while (0)
/*
* Insert a new entry between two known consecutive entries.