new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/bfs/dir.c b/fs/bfs/dir.c
index 2785ef9..3f422f6 100644
--- a/fs/bfs/dir.c
+++ b/fs/bfs/dir.c
@@ -28,7 +28,7 @@
 
 static int bfs_readdir(struct file *f, void *dirent, filldir_t filldir)
 {
-	struct inode *dir = f->f_path.dentry->d_inode;
+	struct inode *dir = file_inode(f);
 	struct buffer_head *bh;
 	struct bfs_dirent *de;
 	struct bfs_sb_info *info = BFS_SB(dir->i_sb);