ext4: create a new function search_dir

search_dirblock is used to search a dir block, but the code is almost
the same for searching an inline dir.

So create a new fuction search_dir and let search_dirblock call it.

Signed-off-by: Tao Ma <boyu.mt@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index e3a7465..a971b65 100644
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -2122,6 +2122,13 @@
 extern int ext4_orphan_del(handle_t *, struct inode *);
 extern int ext4_htree_fill_tree(struct file *dir_file, __u32 start_hash,
 				__u32 start_minor_hash, __u32 *next_hash);
+extern int search_dir(struct buffer_head *bh,
+		      char *search_buf,
+		      int buf_size,
+		      struct inode *dir,
+		      const struct qstr *d_name,
+		      unsigned int offset,
+		      struct ext4_dir_entry_2 **res_dir);
 
 /* resize.c */
 extern int ext4_group_add(struct super_block *sb,