Make the pty driver as close to a cloning device as we can get for now,

we create the pty on the fly when it is first opened.

If you run out of ptys now, just MAKEDEV some more.

This also demonstrate the use of dev_t->si_tty_tty and dev_t->si_drv1
in a device driver.

1 files changed, 62 insertions, 99 deletions

diff --git a/sys/kern/tty_pty.c b/sys/kern/tty_pty.c
index 5a999c3..ae0e9fe 100644
--- a/sys/kern/tty_pty.c
+++ b/sys/kern/tty_pty.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)tty_pty.c	8.4 (Berkeley) 2/20/95
- * $Id: tty_pty.c,v 1.60 1999/05/30 16:52:57 phk Exp $
+ * $Id: tty_pty.c,v 1.61 1999/05/31 11:27:38 phk Exp $
  */
 
 /*
@@ -40,7 +40,6 @@
  */
 #include "pty.h"		/* XXX */
 #include "opt_compat.h"
-#include "opt_devfs.h"
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -55,16 +54,13 @@
 #include <sys/kernel.h>
 #include <sys/vnode.h>
 #include <sys/signalvar.h>
+#include <sys/malloc.h>
 
-#ifdef DEVFS
-#include <sys/devfsext.h>
-#endif /*DEVFS*/
+MALLOC_DEFINE(M_PTY, "ptys", "pty data structures");
 
-#ifdef notyet
-static void ptyattach __P((int n));
-#endif
 static void ptsstart __P((struct tty *tp));
 static void ptcwakeup __P((struct tty *tp, int flag));
+static void ptyinit __P((int n));
 
 static	d_open_t	ptsopen;
 static	d_close_t	ptsclose;
@@ -125,38 +121,15 @@ static struct cdevsw ptc_cdevsw = {
 	/* bmaj */	-1
 };
 
-#if NPTY == 1
-#undef NPTY
-#define	NPTY	32		/* crude XXX */
-#warning	You have only one pty defined, redefining to 32.
-#endif
-
-#ifdef DEVFS
-#define MAXUNITS (8 * 32)
-static	void	*devfs_token_pts[MAXUNITS];
-static	void	*devfs_token_ptc[MAXUNITS];
-static  const	char jnames[] = "pqrsPQRS";
-#if NPTY > MAXUNITS
-#undef NPTY
-#define NPTY MAXUNITS
-#warning	Can't have more than 256 pty's with DEVFS defined.
-#endif
-#endif
-
 #define BUFSIZ 100		/* Chunk size iomoved to/from user */
 
-/*
- * pts == /dev/tty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
- * ptc == /dev/pty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
- */
-static struct	tty pt_tty[NPTY];	/* XXX */
-static struct	pt_ioctl {
+struct	pt_ioctl {
 	int	pt_flags;
 	struct	selinfo pt_selr, pt_selw;
 	u_char	pt_send;
 	u_char	pt_ucntl;
-} pt_ioctl[NPTY];		/* XXX */
-static int	npty = NPTY;		/* for pstat -t */
+	struct tty pt_tty;
+};
 
 #define	PF_PKT		0x08		/* packet mode */
 #define	PF_STOPPED	0x10		/* user told stopped */
@@ -164,32 +137,37 @@ static int	npty = NPTY;		/* for pstat -t */
 #define	PF_NOSTOP	0x40
 #define PF_UCNTL	0x80		/* user control mode */
 
-#ifdef notyet
 /*
- * Establish n (or default if n is 1) ptys in the system.
+ * This function creates and initializes a pts/ptc pair
+ *
+ * pts == /dev/tty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
+ * ptc == /dev/pty[pqrsPQRS][0123456789abcdefghijklmnopqrstuv]
  *
- * XXX cdevsw & pstat require the array `pty[]' to be an array
+ * XXX: define and add mapping of upper minor bits to allow more 
+ *      than 256 ptys.
  */
 static void
-ptyattach(n)
+ptyinit(n)
 	int n;
 {
-	char *mem;
-	register u_long ntb;
-#define	DEFAULT_NPTY	32
-
-	/* maybe should allow 0 => none? */
-	if (n <= 1)
-		n = DEFAULT_NPTY;
-	ntb = n * sizeof(struct tty);
-	mem = malloc(ntb + ALIGNBYTES + n * sizeof(struct pt_ioctl),
-	    M_DEVBUF, M_WAITOK);
-	pt_tty = (struct tty *)mem;
-	mem = (char *)ALIGN(mem + ntb);
-	pt_ioctl = (struct pt_ioctl *)mem;
-	npty = n;
+	dev_t devs, devc;
+	char *names = "pqrsPQRS";
+	struct pt_ioctl *pt;
+
+	/* For now we only map the lower 8 bits of the minor */
+	if (n & ~0xff)
+		return;
+
+	devs = make_dev(&pts_cdevsw, n,
+	    0, 0, 0666, "tty%c%r", names[n / 32], n % 32);
+	devc = make_dev(&ptc_cdevsw, n,
+	    0, 0, 0666, "pty%c%r", names[n / 32], n % 32);
+
+	pt = malloc(sizeof(*pt), M_PTY, M_WAITOK);
+	bzero(pt, sizeof(*pt));
+	devs->si_drv1 = devc->si_drv1 = pt;
+	devs->si_tty_tty = devc->si_tty_tty = &pt->pt_tty;
 }
-#endif
 
 /*ARGSUSED*/
 static	int
@@ -201,9 +179,11 @@ ptsopen(dev, flag, devtype, p)
 	register struct tty *tp;
 	int error;
 
-	if (minor(dev) >= npty)
-		return (ENXIO);
-	tp = &pt_tty[minor(dev)];
+	if (!dev->si_drv1)
+		ptyinit(minor(dev));
+	if (!dev->si_drv1)
+		return(ENXIO);	
+	tp = dev->si_tty_tty;
 	if ((tp->t_state & TS_ISOPEN) == 0) {
 		ttychars(tp);		/* Set up default chars */
 		tp->t_iflag = TTYDEF_IFLAG;
@@ -238,7 +218,7 @@ ptsclose(dev, flag, mode, p)
 	register struct tty *tp;
 	int err;
 
-	tp = &pt_tty[minor(dev)];
+	tp = dev->si_tty_tty;
 	err = (*linesw[tp->t_line].l_close)(tp, flag);
 	ptsstop(tp, FREAD|FWRITE);
 	(void) ttyclose(tp);
@@ -252,8 +232,8 @@ ptsread(dev, uio, flag)
 	int flag;
 {
 	struct proc *p = curproc;
-	register struct tty *tp = &pt_tty[minor(dev)];
-	register struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
+	register struct tty *tp = dev->si_tty_tty;
+	register struct pt_ioctl *pti = dev->si_drv1;
 	int error = 0;
 
 again:
@@ -308,7 +288,7 @@ ptswrite(dev, uio, flag)
 {
 	register struct tty *tp;
 
-	tp = &pt_tty[minor(dev)];
+	tp = dev->si_tty_tty;
 	if (tp->t_oproc == 0)
 		return (EIO);
 	return ((*linesw[tp->t_line].l_write)(tp, uio, flag));
@@ -322,7 +302,7 @@ static void
 ptsstart(tp)
 	struct tty *tp;
 {
-	register struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)];
+	register struct pt_ioctl *pti = tp->t_dev->si_drv1;
 
 	if (tp->t_state & TS_TTSTOP)
 		return;
@@ -338,7 +318,7 @@ ptcwakeup(tp, flag)
 	struct tty *tp;
 	int flag;
 {
-	struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)];
+	struct pt_ioctl *pti = tp->t_dev->si_drv1;
 
 	if (flag & FREAD) {
 		selwakeup(&pti->pt_selr);
@@ -359,18 +339,17 @@ ptcopen(dev, flag, devtype, p)
 	register struct tty *tp;
 	struct pt_ioctl *pti;
 
-	if (minor(dev) >= npty)
-		return (ENXIO);
-	tp = &pt_tty[minor(dev)];
+	if (!dev->si_drv1)
+		ptyinit(minor(dev));
+	if (!dev->si_drv1)
+		return(ENXIO);	
+	tp = dev->si_tty_tty;
 	if (tp->t_oproc)
 		return (EIO);
 	tp->t_oproc = ptsstart;
-#ifdef sun4c
-	tp->t_stop = ptsstop;
-#endif
 	(void)(*linesw[tp->t_line].l_modem)(tp, 1);
 	tp->t_lflag &= ~EXTPROC;
-	pti = &pt_ioctl[minor(dev)];
+	pti = dev->si_drv1;
 	pti->pt_flags = 0;
 	pti->pt_send = 0;
 	pti->pt_ucntl = 0;
@@ -386,7 +365,7 @@ ptcclose(dev, flags, fmt, p)
 {
 	register struct tty *tp;
 
-	tp = &pt_tty[minor(dev)];
+	tp = dev->si_tty_tty;
 	(void)(*linesw[tp->t_line].l_modem)(tp, 0);
 
 	/*
@@ -413,8 +392,8 @@ ptcread(dev, uio, flag)
 	struct uio *uio;
 	int flag;
 {
-	register struct tty *tp = &pt_tty[minor(dev)];
-	struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
+	register struct tty *tp = dev->si_tty_tty;
+	struct pt_ioctl *pti = dev->si_drv1;
 	char buf[BUFSIZ];
 	int error = 0, cc;
 
@@ -474,7 +453,7 @@ ptsstop(tp, flush)
 	register struct tty *tp;
 	int flush;
 {
-	struct pt_ioctl *pti = &pt_ioctl[minor(tp->t_dev)];
+	struct pt_ioctl *pti = tp->t_dev->si_drv1;
 	int flag;
 
 	/* note: FLUSHREAD and FLUSHWRITE already ok */
@@ -499,8 +478,8 @@ ptcpoll(dev, events, p)
 	int events;
 	struct proc *p;
 {
-	register struct tty *tp = &pt_tty[minor(dev)];
-	struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
+	register struct tty *tp = dev->si_tty_tty;
+	struct pt_ioctl *pti = dev->si_drv1;
 	int revents = 0;
 	int s;
 
@@ -549,12 +528,12 @@ ptcwrite(dev, uio, flag)
 	register struct uio *uio;
 	int flag;
 {
-	register struct tty *tp = &pt_tty[minor(dev)];
+	register struct tty *tp = dev->si_tty_tty;
 	register u_char *cp = 0;
 	register int cc = 0;
 	u_char locbuf[BUFSIZ];
 	int cnt = 0;
-	struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
+	struct pt_ioctl *pti = dev->si_drv1;
 	int error = 0;
 
 again:
@@ -657,10 +636,10 @@ static	struct tty *
 ptydevtotty(dev)
 	dev_t		dev;
 {
-	if (minor(dev) >= npty)
+	if (minor(dev) & ~0xff)
 		return (NULL);
 
-	return &pt_tty[minor(dev)];
+	return dev->si_tty_tty;
 }
 
 /*ARGSUSED*/
@@ -672,8 +651,8 @@ ptyioctl(dev, cmd, data, flag, p)
 	int flag;
 	struct proc *p;
 {
-	register struct tty *tp = &pt_tty[minor(dev)];
-	register struct pt_ioctl *pti = &pt_ioctl[minor(dev)];
+	register struct tty *tp = dev->si_tty_tty;
+	register struct pt_ioctl *pti = dev->si_drv1;
 	register u_char *cc = tp->t_cc;
 	int stop, error;
 
@@ -833,35 +812,19 @@ ptyioctl(dev, cmd, data, flag, p)
 	return (error);
 }
 
-static int ptc_devsw_installed;
 
 static void ptc_drvinit __P((void *unused));
+
 static void
 ptc_drvinit(unused)
 	void *unused;
 {
-#ifdef DEVFS
-	int i,j,k;
-#endif
+	static int ptc_devsw_installed;
 
 	if( ! ptc_devsw_installed ) {
 		cdevsw_add(&pts_cdevsw);
 		cdevsw_add(&ptc_cdevsw);
 		ptc_devsw_installed = 1;
-#ifdef DEVFS
-		for ( i = 0 ; i<NPTY ; i++ ) {
-			j = i / 32;
-			k = i % 32;
-			devfs_token_pts[i] = 
-				devfs_add_devswf(&pts_cdevsw,i,
-						DV_CHR,0,0,0666,
-						"tty%c%r",jnames[j],k);
-			devfs_token_ptc[i] =
-				devfs_add_devswf(&ptc_cdevsw,i,
-						DV_CHR,0,0,0666,
-						"pty%c%r",jnames[j],k);
-		}
-#endif
     	}
 }