libfs: Add simple_offset_rename() API

[linux-2.6-block.git] / fs / libfs.c

diff --git a/fs/libfs.c b/fs/libfs.c
index ab61fae92cde8b304dae01817a7f819304904680..c392a6edd3930503724ec65de5d35225ff745481 100644 (file)
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -357,6 +357,27 @@ int simple_offset_empty(struct dentry *dentry)
        return ret;
 }
 
+/**
+ * simple_offset_rename - handle directory offsets for rename
+ * @old_dir: parent directory of source entry
+ * @old_dentry: dentry of source entry
+ * @new_dir: parent_directory of destination entry
+ * @new_dentry: dentry of destination
+ *
+ * Caller provides appropriate serialization.
+ *
+ * Returns zero on success, a negative errno value on failure.
+ */
+int simple_offset_rename(struct inode *old_dir, struct dentry *old_dentry,
+                        struct inode *new_dir, struct dentry *new_dentry)
+{
+       struct offset_ctx *old_ctx = old_dir->i_op->get_offset_ctx(old_dir);
+       struct offset_ctx *new_ctx = new_dir->i_op->get_offset_ctx(new_dir);
+
+       simple_offset_remove(old_ctx, old_dentry);
+       return simple_offset_add(new_ctx, old_dentry);
+}
+
 /**
  * simple_offset_rename_exchange - exchange rename with directory offsets
  * @old_dir: parent of dentry being moved