tandem mode bug fix from Mike Karels; purge spl0's and t_char

SCCS-vsn: sys/kern/tty.c 4.38

diff --git a/usr/src/sys/kern/tty.c b/usr/src/sys/kern/tty.c
index b95e833..ccf9b0c 100644 (file)
--- a/usr/src/sys/kern/tty.c
+++ b/usr/src/sys/kern/tty.c
@@ -115,8 +115,9 @@ ttychars(tp)
 wflushtty(tp)
        register struct tty *tp;
 {
 wflushtty(tp)
        register struct tty *tp;
 {

+       int s;

 
 

-       (void) spl5();
+       s = spl5();

        while (tp->t_outq.c_cc && tp->t_state&TS_CARR_ON
            && tp->t_oproc) {           /* kludge for pty */
                (*tp->t_oproc)(tp);
        while (tp->t_outq.c_cc && tp->t_state&TS_CARR_ON
            && tp->t_oproc) {           /* kludge for pty */
                (*tp->t_oproc)(tp);


@@ -124,7 +125,7 @@ wflushtty(tp)
                sleep((caddr_t)&tp->t_outq, TTOPRI);
        }
        flushtty(tp, FREAD);
                sleep((caddr_t)&tp->t_outq, TTOPRI);
        }
        flushtty(tp, FREAD);

-       (void) spl0();
+       splx(s);

 }
 
 /*
 }
 
 /*


@@ -174,7 +175,6 @@ ttyblock(tp)
        }
        if (x >= TTYHOG/2 && putc(tp->t_stopc, &tp->t_outq) == 0) {
                tp->t_state |= TS_TBLOCK;
        }
        if (x >= TTYHOG/2 && putc(tp->t_stopc, &tp->t_outq) == 0) {
                tp->t_state |= TS_TBLOCK;

-               tp->t_char++;

                ttstart(tp);
        }
 }
                ttstart(tp);
        }
 }


@@ -948,7 +948,7 @@ ttread(tp, uio)
 {
        register struct clist *qp;
        register c, t_flags;
 {
        register struct clist *qp;
        register c, t_flags;

-       int first, error = 0;
+       int s, first, error = 0;

 
        if ((tp->t_state&TS_CARR_ON)==0)
                return (EIO);
 
        if ((tp->t_state&TS_CARR_ON)==0)
                return (EIO);


@@ -956,10 +956,10 @@ loop:
        /*
         * Take any pending input first.
         */
        /*
         * Take any pending input first.
         */

-       (void) spl5();
+       s = spl5();

        if (tp->t_flags&PENDIN)
                ttypend(tp);
        if (tp->t_flags&PENDIN)
                ttypend(tp);

-       (void) spl0();
+       splx(s);

 
        /*
         * Hang process if it's in the background.
 
        /*
         * Hang process if it's in the background.


@@ -983,24 +983,21 @@ loop:
         * device interrupts when interrogating rawq.
         */
        if (t_flags&RAW) {
         * device interrupts when interrogating rawq.
         */
        if (t_flags&RAW) {

-               (void) spl5();
+               s = spl5();

                if (tp->t_rawq.c_cc <= 0) {
                        if ((tp->t_state&TS_CARR_ON) == 0 ||
                            (tp->t_state&TS_NBIO)) {
                if (tp->t_rawq.c_cc <= 0) {
                        if ((tp->t_state&TS_CARR_ON) == 0 ||
                            (tp->t_state&TS_NBIO)) {

-                               (void) spl0();
+                               splx(s);

                                return (0);
                        }
                        sleep((caddr_t)&tp->t_rawq, TTIPRI);
                                return (0);
                        }
                        sleep((caddr_t)&tp->t_rawq, TTIPRI);

-                       (void) spl0();
+                       splx(s);

                        goto loop;
                }
                        goto loop;
                }

-               (void) spl0();
-               while (tp->t_rawq.c_cc && uio->uio_iovcnt) {
+               splx(s);
+               while (!error && tp->t_rawq.c_cc && uio->uio_iovcnt)

                        error = passuc(getc(&tp->t_rawq), uio);
                        error = passuc(getc(&tp->t_rawq), uio);

-                       if (error)
-                               break;
-               }
-               return (error);
+               goto checktandem;

        }
 
        /*
        }
 
        /*


@@ -1013,18 +1010,18 @@ loop:
         * No input, sleep on rawq awaiting hardware
         * receipt and notification.
         */
         * No input, sleep on rawq awaiting hardware
         * receipt and notification.
         */

-       (void) spl5();
+       s = spl5();

        if (qp->c_cc <= 0) {
                if ((tp->t_state&TS_CARR_ON) == 0 ||
                    (tp->t_state&TS_NBIO)) {
        if (qp->c_cc <= 0) {
                if ((tp->t_state&TS_CARR_ON) == 0 ||
                    (tp->t_state&TS_NBIO)) {

-                       (void) spl0();
+                       splx(s);

                        return (EWOULDBLOCK);
                }
                sleep((caddr_t)&tp->t_rawq, TTIPRI);
                        return (EWOULDBLOCK);
                }
                sleep((caddr_t)&tp->t_rawq, TTIPRI);

-               (void) spl0();
+               splx(s);

                goto loop;
        }
                goto loop;
        }

-       (void) spl0();
+       splx(s);

 
        /*
         * Input present, perform input mapping
 
        /*
         * Input present, perform input mapping


@@ -1083,17 +1080,16 @@ loop:
        }
        tp->t_state &= ~TS_BKSL;
 
        }
        tp->t_state &= ~TS_BKSL;
 

+checktandem:

        /*
         * Look to unblock output now that (presumably)
         * the input queue has gone down.
         */
        /*
         * Look to unblock output now that (presumably)
         * the input queue has gone down.
         */

-       if (tp->t_state&TS_TBLOCK && tp->t_rawq.c_cc < TTYHOG/5) {
+       if (tp->t_state&TS_TBLOCK && tp->t_rawq.c_cc < TTYHOG/5)

                if (putc(tp->t_startc, &tp->t_outq) == 0) {
                        tp->t_state &= ~TS_TBLOCK;
                        ttstart(tp);
                }
                if (putc(tp->t_startc, &tp->t_outq) == 0) {
                        tp->t_state &= ~TS_TBLOCK;
                        ttstart(tp);
                }

-               tp->t_char = 0;
-       }

        return (error);
 }
 
        return (error);
 }