[src/trunk]: src/sys/miscfs/specfs When closing a process's controlling termi...

[dsl <dsl%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/412a6e938104
branches:  trunk
changeset: 554990:412a6e938104
user:      dsl <dsl%NetBSD.org@localhost>
date:      Thu Nov 06 08:58:04 2003 +0000

description:
When closing a process's controlling terminal, also remove the links
to the session and pgrp from the tty.  The way that the console is
handled means that the vrele() may not actually do the final close
on the tty itself.

diffstat:

 sys/miscfs/specfs/spec_vnops.c |  17 +++++++++++++----
 1 files changed, 13 insertions(+), 4 deletions(-)

diffs (56 lines):

diff -r 9178b33a1b35 -r 412a6e938104 sys/miscfs/specfs/spec_vnops.c
--- a/sys/miscfs/specfs/spec_vnops.c    Thu Nov 06 08:49:13 2003 +0000
+++ b/sys/miscfs/specfs/spec_vnops.c    Thu Nov 06 08:58:04 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: spec_vnops.c,v 1.70 2003/10/15 08:41:26 dsl Exp $      */
+/*     $NetBSD: spec_vnops.c,v 1.71 2003/11/06 08:58:04 dsl Exp $      */
 
 /*
  * Copyright (c) 1989, 1993
@@ -32,7 +32,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: spec_vnops.c,v 1.70 2003/10/15 08:41:26 dsl Exp $");
+__KERNEL_RCSID(0, "$NetBSD: spec_vnops.c,v 1.71 2003/11/06 08:58:04 dsl Exp $");
 
 #include <sys/param.h>
 #include <sys/proc.h>
@@ -49,6 +49,7 @@
 #include <sys/file.h>
 #include <sys/disklabel.h>
 #include <sys/lockf.h>
+#include <sys/tty.h>
 
 #include <miscfs/genfs/genfs.h>
 #include <miscfs/specfs/specdev.h>
@@ -645,6 +646,7 @@
        struct vnode *vp = ap->a_vp;
        const struct bdevsw *bdev;
        const struct cdevsw *cdev;
+       struct session *sess;
        dev_t dev = vp->v_rdev;
        int (*devclose) __P((dev_t, int, int, struct proc *));
        int mode, error, count, flags, flags1;
@@ -665,12 +667,19 @@
                 * process' controlling terminal.  In that case,
                 * if the reference count is 2 (this last descriptor
                 * plus the session), release the reference from the session.
+                * Also remove the link from the tty back to the session
+                * and pgrp - due to the way consoles are handled we cannot
+                * guarantee that the vrele() will do the final close on the
+                * actual tty device.
                 */
                if (count == 2 && ap->a_p &&
-                   vp == ap->a_p->p_session->s_ttyvp) {
+                   vp == (sess = ap->a_p->p_session)->s_ttyvp) {
+                       sess->s_ttyvp = NULL;
+                       sess->s_ttyp->t_pgrp = NULL;
+                       sess->s_ttyp->t_session = NULL;
+                       SESSRELE(sess);
                        vrele(vp);
                        count--;
-                       ap->a_p->p_session->s_ttyvp = NULL;
                }
                /*
                 * If the vnode is locked, then we are in the midst