Reintroduce the cioctl() hook in the TTY layer for digi(4).

The cioctl() hook can be used by drivers to add ioctls to the *.init and
*.lock devices. This commit breaks the ttydevsw ABI, since this
structure didn't provide any padding. To prevent ABI breakage in the
future, add a tsw_spare.

Submitted by:	Peter Jeremy <peter jeremy alcatel lucent com>
Obtained from:	kern/152254 (slightly modified)

1 files changed, 14 insertions, 0 deletions

diff --git a/sys/sys/ttydevsw.h b/sys/sys/ttydevsw.h
index 4506919..748ae0b 100644
--- a/sys/sys/ttydevsw.h
+++ b/sys/sys/ttydevsw.h
@@ -46,6 +46,8 @@ typedef void tsw_outwakeup_t(struct tty *tp);
 typedef void tsw_inwakeup_t(struct tty *tp);
 typedef int tsw_ioctl_t(struct tty *tp, u_long cmd, caddr_t data,
     struct thread *td);
+typedef int tsw_cioctl_t(struct tty *tp, int unit, u_long cmd, caddr_t data,
+    struct thread *td);
 typedef int tsw_param_t(struct tty *tp, struct termios *t);
 typedef int tsw_modem_t(struct tty *tp, int sigon, int sigoff);
 typedef int tsw_mmap_t(struct tty *tp, vm_ooffset_t offset,
@@ -63,6 +65,7 @@ struct ttydevsw {
 	tsw_inwakeup_t	*tsw_inwakeup;	/* Input can be stored again. */
 
 	tsw_ioctl_t	*tsw_ioctl;	/* ioctl() hooks. */
+	tsw_cioctl_t	*tsw_cioctl;	/* ioctl() on control devices. */
 	tsw_param_t	*tsw_param;	/* TIOCSETA device parameter setting. */
 	tsw_modem_t	*tsw_modem;	/* Modem sigon/sigoff. */
 
@@ -70,6 +73,8 @@ struct ttydevsw {
 	tsw_pktnotify_t	*tsw_pktnotify;	/* TIOCPKT events. */
 
 	tsw_free_t	*tsw_free;	/* Destructor. */
+
+	void		*tsw_spare[4];	/* For future use. */
 };
 
 static __inline int
@@ -126,6 +131,15 @@ ttydevsw_ioctl(struct tty *tp, u_long cmd, caddr_t data, struct thread *td)
 }
 
 static __inline int
+ttydevsw_cioctl(struct tty *tp, int unit, u_long cmd, caddr_t data, struct thread *td)
+{
+	tty_lock_assert(tp, MA_OWNED);
+	MPASS(!tty_gone(tp));
+
+	return tp->t_devsw->tsw_cioctl(tp, unit, cmd, data, td);
+}
+
+static __inline int
 ttydevsw_param(struct tty *tp, struct termios *t)
 {
 	MPASS(!tty_gone(tp));