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-rw-r--r--fs/yaffs2/yaffs_list.h126
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diff --git a/fs/yaffs2/yaffs_list.h b/fs/yaffs2/yaffs_list.h
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+/*
+ * YAFFS: Yet another Flash File System . A NAND-flash specific file system.
+ *
+ * Copyright (C) 2002-2011 Aleph One Ltd.
+ * for Toby Churchill Ltd and Brightstar Engineering
+ *
+ * Created by Charles Manning <charles@aleph1.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1 as
+ * published by the Free Software Foundation.
+ *
+ * Note: Only YAFFS headers are LGPL, YAFFS C code is covered by GPL.
+ */
+
+/*
+ * This file is just holds extra declarations of macros that would normally
+ * be providesd in the Linux kernel. These macros have been written from
+ * scratch but are functionally equivalent to the Linux ones.
+ *
+ */
+
+#ifndef __YAFFS_LIST_H__
+#define __YAFFS_LIST_H__
+
+
+/*
+ * This is a simple doubly linked list implementation that matches the
+ * way the Linux kernel doubly linked list implementation works.
+ */
+
+struct list_head {
+ struct list_head *next; /* next in chain */
+ struct list_head *prev; /* previous in chain */
+};
+
+
+/* Initialise a static list */
+#define LIST_HEAD(name) \
+struct list_head name = { &(name), &(name)}
+
+
+
+/* Initialise a list head to an empty list */
+#define INIT_LIST_HEAD(p) \
+do { \
+ (p)->next = (p);\
+ (p)->prev = (p); \
+} while (0)
+
+
+/* Add an element to a list */
+static inline void list_add(struct list_head *new_entry,
+ struct list_head *list)
+{
+ struct list_head *list_next = list->next;
+
+ list->next = new_entry;
+ new_entry->prev = list;
+ new_entry->next = list_next;
+ list_next->prev = new_entry;
+
+}
+
+static inline void list_add_tail(struct list_head *new_entry,
+ struct list_head *list)
+{
+ struct list_head *list_prev = list->prev;
+
+ list->prev = new_entry;
+ new_entry->next = list;
+ new_entry->prev = list_prev;
+ list_prev->next = new_entry;
+
+}
+
+
+/* Take an element out of its current list, with or without
+ * reinitialising the links.of the entry*/
+static inline void list_del(struct list_head *entry)
+{
+ struct list_head *list_next = entry->next;
+ struct list_head *list_prev = entry->prev;
+
+ list_next->prev = list_prev;
+ list_prev->next = list_next;
+
+}
+
+static inline void list_del_init(struct list_head *entry)
+{
+ list_del(entry);
+ entry->next = entry->prev = entry;
+}
+
+
+/* Test if the list is empty */
+static inline int list_empty(struct list_head *entry)
+{
+ return (entry->next == entry);
+}
+
+
+/* list_entry takes a pointer to a list entry and offsets it to that
+ * we can find a pointer to the object it is embedded in.
+ */
+
+
+#define list_entry(entry, type, member) \
+ ((type *)((char *)(entry)-(unsigned long)(&((type *)NULL)->member)))
+
+
+/* list_for_each and list_for_each_safe iterate over lists.
+ * list_for_each_safe uses temporary storage to make the list delete safe
+ */
+
+#define list_for_each(itervar, list) \
+ for (itervar = (list)->next; itervar != (list); itervar = itervar->next)
+
+#define list_for_each_safe(itervar, save_var, list) \
+ for (itervar = (list)->next, save_var = (list)->next->next; \
+ itervar != (list); \
+ itervar = save_var, save_var = save_var->next)
+
+
+#endif
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