diff --git a/include/linux/tty.h b/include/linux/tty.h
index 5972f43b9d5a..94fa384a650b 100644
--- a/include/linux/tty.h
+++ b/include/linux/tty.h
@@ -303,6 +303,10 @@ struct tty_struct {
 	spinlock_t flow_lock;
 	/* Termios values are protected by the termios rwsem */
 	struct ktermios termios, termios_locked;
+
+	/* termiox is estored only for ABI preservation, do not use */
+	struct termiox *termiox;
+
 	char name[64];
 	struct pid *pgrp;		/* Protected by ctrl lock */
 	/*
diff --git a/include/linux/tty_driver.h b/include/linux/tty_driver.h
index 2f719b471d52..5d509c125171 100644
--- a/include/linux/tty_driver.h
+++ b/include/linux/tty_driver.h
@@ -277,6 +277,10 @@ struct tty_operations {
 	int (*tiocmset)(struct tty_struct *tty,
 			unsigned int set, unsigned int clear);
 	int (*resize)(struct tty_struct *tty, struct winsize *ws);
+
+	/* only for abi preservation */
+	int (*set_termiox)(struct tty_struct *tty, struct termiox *tnew);
+
 	int (*get_icount)(struct tty_struct *tty,
 				struct serial_icounter_struct *icount);
 	int  (*get_serial)(struct tty_struct *tty, struct serial_struct *p);