[src/trunk]: src/sys/fs/ptyfs use a counter to prevent from mounting ptyfs tw...

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

details:   https://anonhg.NetBSD.org/src/rev/2438f97846ce
branches:  trunk
changeset: 584783:2438f97846ce
user:      christos <christos%NetBSD.org@localhost>
date:      Sat Oct 01 05:30:12 2005 +0000

description:
use a counter to prevent from mounting ptyfs twice. Using save_ptm is not
good enough, because if we don't have COMPAT_BSDPTY, then it will stay NULL.

diffstat:

 sys/fs/ptyfs/ptyfs_vfsops.c |  10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diffs (59 lines):

diff -r 63abbb2c8891 -r 2438f97846ce sys/fs/ptyfs/ptyfs_vfsops.c
--- a/sys/fs/ptyfs/ptyfs_vfsops.c       Sat Oct 01 04:11:19 2005 +0000
+++ b/sys/fs/ptyfs/ptyfs_vfsops.c       Sat Oct 01 05:30:12 2005 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ptyfs_vfsops.c,v 1.10 2005/09/29 14:45:56 christos Exp $       */
+/*     $NetBSD: ptyfs_vfsops.c,v 1.11 2005/10/01 05:30:12 christos Exp $       */
 
 /*
  * Copyright (c) 1992, 1993, 1995
@@ -38,7 +38,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ptyfs_vfsops.c,v 1.10 2005/09/29 14:45:56 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ptyfs_vfsops.c,v 1.11 2005/10/01 05:30:12 christos Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -82,6 +82,7 @@
  * ptm glue: When we mount, we make ptm point to us.
  */
 struct ptm_pty *ptyfs_save_ptm;
+static int ptyfs_count;
 
 struct ptm_pty ptm_ptyfspty = {
        ptyfs__allocvp,
@@ -186,7 +187,7 @@
        struct ptyfs_args args;
 
        /* Don't allow more than one mount */
-       if (ptyfs_save_ptm != NULL)
+       if (ptyfs_count)
                return EBUSY;
 
        if (UIO_MX & (UIO_MX - 1)) {
@@ -239,6 +240,7 @@
 
        ptm_ptyfspty.arg = mp;
        ptyfs_save_ptm = pty_sethandler(&ptm_ptyfspty);
+       ptyfs_count++;
        return 0;
 }
 
@@ -263,7 +265,6 @@
                return (error);
 
        /* Restore where pty access was pointing */
-       KASSERT(ptyfs_save_ptm != NULL);
        (void)pty_sethandler(ptyfs_save_ptm);
        ptyfs_save_ptm = NULL;
        ptm_ptyfspty.arg = NULL;
@@ -273,6 +274,7 @@
         */
        free(mp->mnt_data, M_UFSMNT);
        mp->mnt_data = 0;
+       ptyfs_count--;
 
        return 0;
 }