new helper: file_inode(file)

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/drivers/s390/char/fs3270.c b/drivers/s390/char/fs3270.c
index 9117045..5acdc5f 100644
--- a/drivers/s390/char/fs3270.c
+++ b/drivers/s390/char/fs3270.c
@@ -433,9 +433,9 @@
 	struct idal_buffer *ib;
 	int minor, rc = 0;
 
-	if (imajor(filp->f_path.dentry->d_inode) != IBM_FS3270_MAJOR)
+	if (imajor(file_inode(filp)) != IBM_FS3270_MAJOR)
 		return -ENODEV;
-	minor = iminor(filp->f_path.dentry->d_inode);
+	minor = iminor(file_inode(filp));
 	/* Check for minor 0 multiplexer. */
 	if (minor == 0) {
 		struct tty_struct *tty = get_current_tty();