[src/trunk]: src/sys/dev/dkwedge Make sure to release sc_parent->dk_rawlock b...

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

details:   https://anonhg.NetBSD.org/src/rev/93c229ca0a08
branches:  trunk
changeset: 756816:93c229ca0a08
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Wed Aug 04 12:34:00 2010 +0000

description:
Make sure to release sc_parent->dk_rawlock before calling
vn_close(sc->sc_parent->dk_rawvp). Avoids a lockdebug panic:
error: mutex_destroy: assertion failed: !MUTEX_OWNED(mtx->mtx_owner) && !MUTEX_HAS_WAITERS(mtx)
when the parent is a raidframe device.
See also:
http://mail-index.netbsd.org/tech-kern/2010/07/27/msg008612.html

diffstat:

 sys/dev/dkwedge/dk.c |  28 ++++++++++++++++------------
 1 files changed, 16 insertions(+), 12 deletions(-)

diffs (86 lines):

diff -r 0c984f9379ed -r 93c229ca0a08 sys/dev/dkwedge/dk.c
--- a/sys/dev/dkwedge/dk.c      Wed Aug 04 11:39:14 2010 +0000
+++ b/sys/dev/dkwedge/dk.c      Wed Aug 04 12:34:00 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: dk.c,v 1.56 2010/06/24 13:03:08 hannken Exp $  */
+/*     $NetBSD: dk.c,v 1.57 2010/08/04 12:34:00 bouyer Exp $   */
 
 /*-
  * Copyright (c) 2004, 2005, 2006, 2007 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.56 2010/06/24 13:03:08 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: dk.c,v 1.57 2010/08/04 12:34:00 bouyer Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_dkwedge.h"
@@ -511,14 +511,14 @@
 
        rc = 0;
        mutex_enter(&dk->dk_openlock);
-       mutex_enter(&sc->sc_parent->dk_rawlock);
        if (dk->dk_openmask == 0)
                ;       /* nothing to do */
        else if ((flags & DETACH_FORCE) == 0)
                rc = EBUSY;
-       else
-               rc = dklastclose(sc);
-       mutex_exit(&sc->sc_parent->dk_rawlock);
+       else {
+               mutex_enter(&sc->sc_parent->dk_rawlock);
+               rc = dklastclose(sc); /* releases dk_rawlock */
+       }
        mutex_exit(&dk->dk_openlock);
 
        return rc;
@@ -577,17 +577,18 @@
 
        /* Clean up the parent. */
        mutex_enter(&sc->sc_dk.dk_openlock);
-       mutex_enter(&sc->sc_parent->dk_rawlock);
        if (sc->sc_dk.dk_openmask) {
+               mutex_enter(&sc->sc_parent->dk_rawlock);
                if (sc->sc_parent->dk_rawopens-- == 1) {
                        KASSERT(sc->sc_parent->dk_rawvp != NULL);
+                       mutex_exit(&sc->sc_parent->dk_rawlock);
                        (void) vn_close(sc->sc_parent->dk_rawvp, FREAD | FWRITE,
                            NOCRED);
                        sc->sc_parent->dk_rawvp = NULL;
-               }
+               } else
+                       mutex_exit(&sc->sc_parent->dk_rawlock);
                sc->sc_dk.dk_openmask = 0;
        }
-       mutex_exit(&sc->sc_parent->dk_rawlock);
        mutex_exit(&sc->sc_dk.dk_openlock);
 
        /* Announce our departure. */
@@ -1050,10 +1051,12 @@
 
        if (sc->sc_parent->dk_rawopens-- == 1) {
                KASSERT(sc->sc_parent->dk_rawvp != NULL);
+               mutex_exit(&sc->sc_parent->dk_rawlock);
                error = vn_close(sc->sc_parent->dk_rawvp,
                    FREAD | FWRITE, NOCRED);
                sc->sc_parent->dk_rawvp = NULL;
-       }
+       } else
+               mutex_exit(&sc->sc_parent->dk_rawlock);
        return error;
 }
 
@@ -1081,9 +1084,10 @@
            sc->sc_dk.dk_copenmask | sc->sc_dk.dk_bopenmask;
 
        if (sc->sc_dk.dk_openmask == 0)
-               error = dklastclose(sc);
+               error = dklastclose(sc); /* releases dk_rawlock */
+       else 
+               mutex_exit(&sc->sc_parent->dk_rawlock);
 
-       mutex_exit(&sc->sc_parent->dk_rawlock);
        mutex_exit(&sc->sc_dk.dk_openlock);
 
        return (error);