+#ifndef _LINUX_FLIST_H
+#define _LINUX_FLIST_H
+
+#undef offsetof
+#ifdef __compiler_offsetof
+#define offsetof(TYPE,MEMBER) __compiler_offsetof(TYPE,MEMBER)
+#else
+#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+#endif
+
+#define container_of(ptr, type, member) ({ \
+ const typeof( ((type *)0)->member ) *__mptr = (ptr); \
+ (type *)( (char *)__mptr - offsetof(type,member) );})
+
+/*
+ * Simple doubly linked list implementation.
+ *
+ * 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 flist_head {
+ struct flist_head *next, *prev;
+};
+
+#define FLIST_HEAD_INIT(name) { &(name), &(name) }
+
+#define FLIST_HEAD(name) \
+ struct flist_head name = FLIST_HEAD_INIT(name)
+
+#define INIT_FLIST_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 list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __flist_add(struct flist_head *new,
+ struct flist_head *prev,
+ struct flist_head *next)
+{
+ next->prev = new;
+ new->next = next;
+ new->prev = prev;
+ prev->next = new;
+}
+
+/**
+ * flist_add - add a new entry
+ * @new: new entry to be added
+ * @head: list head to add it after
+ *
+ * Insert a new entry after the specified head.
+ * This is good for implementing stacks.
+ */
+static inline void flist_add(struct flist_head *new, struct flist_head *head)
+{
+ __flist_add(new, head, head->next);
+}
+
+static inline void flist_add_tail(struct flist_head *new,
+ struct flist_head *head)
+{
+ __flist_add(new, head->prev, head);
+}
+
+/*
+ * Delete a list entry by making the prev/next entries
+ * point to each other.
+ *
+ * This is only for internal list manipulation where we know
+ * the prev/next entries already!
+ */
+static inline void __flist_del(struct flist_head *prev,
+ struct flist_head * next)
+{
+ next->prev = prev;
+ prev->next = next;
+}
+
+/**
+ * flist_del - deletes entry from list.
+ * @entry: the element to delete from the list.
+ * Note: flist_empty on entry does not return true after this, the entry is
+ * in an undefined state.
+ */
+static inline void flist_del(struct flist_head *entry)
+{
+ __flist_del(entry->prev, entry->next);
+ entry->next = NULL;
+ entry->prev = NULL;
+}
+
+/**
+ * flist_del_init - deletes entry from list and reinitialize it.
+ * @entry: the element to delete from the list.
+ */
+static inline void flist_del_init(struct flist_head *entry)
+{
+ __flist_del(entry->prev, entry->next);
+ INIT_FLIST_HEAD(entry);
+}
+
+/**
+ * flist_empty - tests whether a list is empty
+ * @head: the list to test.
+ */
+static inline int flist_empty(const struct flist_head *head)
+{
+ return head->next == head;
+}
+
+/**
+ * flist_entry - get the struct for this entry
+ * @ptr: the &struct flist_head pointer.
+ * @type: the type of the struct this is embedded in.
+ * @member: the name of the flist_struct within the struct.
+ */
+#define flist_entry(ptr, type, member) \
+ container_of(ptr, type, member)
+
+/**
+ * flist_for_each - iterate over a list
+ * @pos: the &struct flist_head to use as a loop counter.
+ * @head: the head for your list.
+ */
+#define flist_for_each(pos, head) \
+ for (pos = (head)->next; pos != (head); pos = pos->next)
+
+/**
+ * flist_for_each_safe - iterate over a list safe against removal of list entry
+ * @pos: the &struct flist_head to use as a loop counter.
+ * @n: another &struct flist_head to use as temporary storage
+ * @head: the head for your list.
+ */
+#define flist_for_each_safe(pos, n, head) \
+ for (pos = (head)->next, n = pos->next; pos != (head); \
+ pos = n, n = pos->next)
+
+#endif
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