zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/fs/btrfs/extent_map.h b/ap/os/linux/linux-3.4.x/fs/btrfs/extent_map.h
new file mode 100644
index 0000000..1195f09
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/fs/btrfs/extent_map.h
@@ -0,0 +1,66 @@
+#ifndef __EXTENTMAP__
+#define __EXTENTMAP__
+
+#include <linux/rbtree.h>
+
+#define EXTENT_MAP_LAST_BYTE (u64)-4
+#define EXTENT_MAP_HOLE (u64)-3
+#define EXTENT_MAP_INLINE (u64)-2
+#define EXTENT_MAP_DELALLOC (u64)-1
+
+/* bits for the flags field */
+#define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */
+#define EXTENT_FLAG_COMPRESSED 1
+#define EXTENT_FLAG_VACANCY 2 /* no file extent item found */
+#define EXTENT_FLAG_PREALLOC 3 /* pre-allocated extent */
+
+struct extent_map {
+ struct rb_node rb_node;
+
+ /* all of these are in bytes */
+ u64 start;
+ u64 len;
+ u64 orig_start;
+ u64 block_start;
+ u64 block_len;
+ unsigned long flags;
+ struct block_device *bdev;
+ atomic_t refs;
+ unsigned int in_tree;
+ unsigned int compress_type;
+};
+
+struct extent_map_tree {
+ struct rb_root map;
+ rwlock_t lock;
+};
+
+static inline u64 extent_map_end(struct extent_map *em)
+{
+ if (em->start + em->len < em->start)
+ return (u64)-1;
+ return em->start + em->len;
+}
+
+static inline u64 extent_map_block_end(struct extent_map *em)
+{
+ if (em->block_start + em->block_len < em->block_start)
+ return (u64)-1;
+ return em->block_start + em->block_len;
+}
+
+void extent_map_tree_init(struct extent_map_tree *tree);
+struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
+ u64 start, u64 len);
+int add_extent_mapping(struct extent_map_tree *tree,
+ struct extent_map *em);
+int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
+
+struct extent_map *alloc_extent_map(void);
+void free_extent_map(struct extent_map *em);
+int __init extent_map_init(void);
+void extent_map_exit(void);
+int unpin_extent_cache(struct extent_map_tree *tree, u64 start, u64 len);
+struct extent_map *search_extent_mapping(struct extent_map_tree *tree,
+ u64 start, u64 len);
+#endif