Fix an issue with ng_tty which (ab)used the tty->t_sc field which is

reserved for the device drivers:

Add a t_lsc field for line discipline private use.

3 files changed, 13 insertions, 10 deletions

diff --git a/sys/dev/sio/sio.c b/sys/dev/sio/sio.c
index 599f188..9fbfad8 100644
--- a/sys/dev/sio/sio.c
+++ b/sys/dev/sio/sio.c
@@ -1152,8 +1152,10 @@ determined_type: ;
 	com->devs[5] = make_dev(&sioc_cdevsw,
 	    minorbase | CALLOUT_MASK | CONTROL_LOCK_STATE,
 	    UID_UUCP, GID_DIALER, 0660, "cuala%r", unit);
-	for (rid = 0; rid < 6; rid++)
+	for (rid = 0; rid < 6; rid++) {
 		com->devs[rid]->si_drv1 = com;
+		com->devs[rid]->si_tty = tp;
+	}
 	com->flags = flags;
 	com->pps.ppscap = PPS_CAPTUREASSERT | PPS_CAPTURECLEAR;
 
@@ -1523,7 +1525,7 @@ siowrite(dev, uio, flag)
 	mynor = minor(dev);
 
 	unit = MINOR_TO_UNIT(mynor);
-	com = com_addr(unit);
+	com = dev->si_drv1;
 	if (com == NULL || com->gone)
 		return (ENODEV);
 	/*
@@ -1991,10 +1993,10 @@ siocioctl(dev, cmd, data, flag, td)
 	struct termios	*ct;
 
 	mynor = minor(dev);
-	com = com_addr(MINOR_TO_UNIT(mynor));
-	tp = com->tp;
+	com = dev->si_drv1;
 	if (com == NULL || com->gone)
 		return (ENODEV);
+	tp = com->tp;
 
 	switch (mynor & CONTROL_MASK) {
 	case CONTROL_INIT_STATE:
diff --git a/sys/netgraph/ng_tty.c b/sys/netgraph/ng_tty.c
index 9ae20a0..f29b75f 100644
--- a/sys/netgraph/ng_tty.c
+++ b/sys/netgraph/ng_tty.c
@@ -239,7 +239,7 @@ ngt_open(struct cdev *dev, struct tty *tp)
 
 	/* Set back pointers */
 	NG_NODE_SET_PRIVATE(sc->node, sc);
-	tp->t_sc = (caddr_t) sc;
+	tp->t_lsc = sc;
 
 	/*
 	 * Pre-allocate cblocks to the an appropriate amount.
@@ -265,7 +265,7 @@ done:
 static int
 ngt_close(struct tty *tp, int flag)
 {
-	const sc_p sc = (sc_p) tp->t_sc;
+	const sc_p sc = (sc_p) tp->t_lsc;
 	int s;
 
 	s = spltty();
@@ -279,7 +279,7 @@ ngt_close(struct tty *tp, int flag)
 		ngt_nodeop_ok = 1;
 		ng_rmnode_self(sc->node);
 		ngt_nodeop_ok = 0;
-		tp->t_sc = NULL;
+		tp->t_lsc = NULL;
 	}
 	splx(s);
 	return (0);
@@ -309,7 +309,7 @@ ngt_write(struct tty *tp, struct uio *uio, int flag)
 static int
 ngt_tioctl(struct tty *tp, u_long cmd, caddr_t data, int flag, struct thread *td)
 {
-	const sc_p sc = (sc_p) tp->t_sc;
+	const sc_p sc = (sc_p) tp->t_lsc;
 	int s, error = 0;
 
 	s = spltty();
@@ -343,7 +343,7 @@ done:
 static int
 ngt_input(int c, struct tty *tp)
 {
-	const sc_p sc = (sc_p) tp->t_sc;
+	const sc_p sc = (sc_p) tp->t_lsc;
 	const node_p node = sc->node;
 	struct mbuf *m;
 	int s, error = 0;
@@ -408,7 +408,7 @@ done:
 static int
 ngt_start(struct tty *tp)
 {
-	const sc_p sc = (sc_p) tp->t_sc;
+	const sc_p sc = (sc_p) tp->t_lsc;
 	int s;
 
 	s = spltty();
diff --git a/sys/sys/tty.h b/sys/sys/tty.h
index eb45490..fdbdc72 100644
--- a/sys/sys/tty.h
+++ b/sys/sys/tty.h
@@ -114,6 +114,7 @@ struct tty {
 	struct	termios t_lock_out;	/* ... outgoing */
 	struct	winsize t_winsize;	/* Window size. */
 	void	*t_sc;			/* driver private softc pointer. */
+	void	*t_lsc;			/* linedisc private softc pointer. */
 	int	t_column;		/* Tty output column. */
 	int	t_rocount, t_rocol;	/* Tty. */
 	int	t_ififosize;		/* Total size of upstream fifos. */