new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/drivers/video/fb_defio.c b/drivers/video/fb_defio.c
index 88cad6b..900aa4e 100644
--- a/drivers/video/fb_defio.c
+++ b/drivers/video/fb_defio.c
@@ -69,7 +69,7 @@
 int fb_deferred_io_fsync(struct file *file, loff_t start, loff_t end, int datasync)
 {
 	struct fb_info *info = file->private_data;
-	struct inode *inode = file->f_path.dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	int err = filemap_write_and_wait_range(inode->i_mapping, start, end);
 	if (err)
 		return err;