nilfs2: move definition of struct nilfs_btree_node
This is a trivial patch to expose struct nilfs_fs_btree_node.
The struct should be exposed outside of kernel, for it is disk format.
Signed-off-by: Jiro SEKIBA <jir@unicus.jp>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/include/linux/nilfs2_fs.h b/include/linux/nilfs2_fs.h
index ce52040..72289d2 100644
--- a/include/linux/nilfs2_fs.h
+++ b/include/linux/nilfs2_fs.h
@@ -403,6 +403,28 @@
#define NILFS_SS_GC 0x0010 /* segment written for cleaner operation */
/**
+ * struct nilfs_btree_node - B-tree node
+ * @bn_flags: flags
+ * @bn_level: level
+ * @bn_nchildren: number of children
+ * @bn_pad: padding
+ */
+struct nilfs_btree_node {
+ __u8 bn_flags;
+ __u8 bn_level;
+ __le16 bn_nchildren;
+ __le32 bn_pad;
+};
+
+/* flags */
+#define NILFS_BTREE_NODE_ROOT 0x01
+
+/* level */
+#define NILFS_BTREE_LEVEL_DATA 0
+#define NILFS_BTREE_LEVEL_NODE_MIN (NILFS_BTREE_LEVEL_DATA + 1)
+#define NILFS_BTREE_LEVEL_MAX 14
+
+/**
* struct nilfs_palloc_group_desc - block group descriptor
* @pg_nfrees: number of free entries in block group
*/