call ttystart before checking for queue overflow,

instead of afterward (if it's synchronous, we hang); call driver oproc
at normal priority, and let it check for timeout,etc (they all do anyway).

SCCS-vsn: sys/kern/tty.c 7.7

diff --git a/usr/src/sys/kern/tty.c b/usr/src/sys/kern/tty.c
index 5d80865..a0ab30b 100644 (file)
--- a/usr/src/sys/kern/tty.c
+++ b/usr/src/sys/kern/tty.c
@@ -3,7 +3,7 @@
  * All rights reserved.  The Berkeley software License Agreement
  * specifies the terms and conditions for redistribution.
  *
  * All rights reserved.  The Berkeley software License Agreement
  * specifies the terms and conditions for redistribution.
  *

- *     @(#)tty.c       7.6 (Berkeley) %G%
+ *     @(#)tty.c       7.7 (Berkeley) %G%

  */
 
 #include "../machine/reg.h"
  */
 
 #include "../machine/reg.h"


@@ -222,13 +222,9 @@ ttrstrt(tp)
 ttstart(tp)
        register struct tty *tp;
 {
 ttstart(tp)
        register struct tty *tp;
 {

-       register s;

 
 

-       s = spltty();
-       if ((tp->t_state & (TS_TIMEOUT|TS_TTSTOP|TS_BUSY)) == 0 &&
-           tp->t_oproc)                /* kludge for pty */
+       if (tp->t_oproc)                /* kludge for pty */

                (*tp->t_oproc)(tp);
                (*tp->t_oproc)(tp);

-       splx(s);

 }
 
 /*
 }
 
 /*


@@ -1338,6 +1334,10 @@ loop:
         * in acquiring new space.
         */
        while (uio->uio_resid > 0) {
         * in acquiring new space.
         */
        while (uio->uio_resid > 0) {

+               if (tp->t_outq.c_cc > hiwat) {
+                       cc = 0;
+                       goto ovhiwat;
+               }

                /*
                 * Grab a hunk of data from the user.
                 */
                /*
                 * Grab a hunk of data from the user.
                 */


@@ -1355,8 +1355,6 @@ loop:
                error = uiomove(cp, cc, UIO_WRITE, uio);
                if (error)
                        break;
                error = uiomove(cp, cc, UIO_WRITE, uio);
                if (error)
                        break;

-               if (tp->t_outq.c_cc > hiwat)
-                       goto ovhiwat;

                if (tp->t_flags&FLUSHO)
                        continue;
                /*
                if (tp->t_flags&FLUSHO)
                        continue;
                /*


@@ -1458,22 +1456,22 @@ loop:
        return (error);
 
 ovhiwat:
        return (error);
 
 ovhiwat:

-       s = spltty();

        if (cc != 0) {
                uio->uio_iov->iov_base -= cc;
                uio->uio_iov->iov_len += cc;
                uio->uio_resid += cc;
                uio->uio_offset -= cc;
        }
        if (cc != 0) {
                uio->uio_iov->iov_base -= cc;
                uio->uio_iov->iov_len += cc;
                uio->uio_resid += cc;
                uio->uio_offset -= cc;
        }

+       ttstart(tp);
+       s = spltty();

        /*
        /*

-        * This can only occur if FLUSHO
-        * is also set in t_flags.
+        * This can only occur if FLUSHO is set in t_flags,
+        * or if ttstart/oproc is synchronous (or very fast).

         */
        if (tp->t_outq.c_cc <= hiwat) {
                splx(s);
                goto loop;
        }
         */
        if (tp->t_outq.c_cc <= hiwat) {
                splx(s);
                goto loop;
        }

-       ttstart(tp);

        if (tp->t_state&TS_NBIO) {
                splx(s);
                if (uio->uio_resid == cnt)
        if (tp->t_state&TS_NBIO) {
                splx(s);
                if (uio->uio_resid == cnt)