[src/trunk]: src/sys/kern description:

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

details:   https://anonhg.NetBSD.org/src/rev/e62edd543761
branches:  trunk
changeset: 764062:e62edd543761
user:      dholland <dholland%NetBSD.org@localhost>
date:      Mon Apr 11 02:11:32 2011 +0000

description:
description:
In lookup_once(), move the assignments to ni_dvp and ni_vp to just
before function return.

diffstat:

 sys/kern/vfs_lookup.c |  33 +++++++++++++++++----------------
 1 files changed, 17 insertions(+), 16 deletions(-)

diffs (91 lines):

diff -r 638e5beec3c5 -r e62edd543761 sys/kern/vfs_lookup.c
--- a/sys/kern/vfs_lookup.c     Mon Apr 11 01:44:15 2011 +0000
+++ b/sys/kern/vfs_lookup.c     Mon Apr 11 02:11:32 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_lookup.c,v 1.147 2011/04/11 01:40:13 dholland Exp $        */
+/*     $NetBSD: vfs_lookup.c,v 1.148 2011/04/11 02:11:32 dholland Exp $        */
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1993
@@ -37,7 +37,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_lookup.c,v 1.147 2011/04/11 01:40:13 dholland Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_lookup.c,v 1.148 2011/04/11 02:11:32 dholland Exp $");
 
 #include "opt_magiclinks.h"
 
@@ -938,12 +938,11 @@
         * Our vnode state here is that "searchdir" is held and locked.
         */
 unionlookup:
-       ndp->ni_dvp = searchdir;
-       ndp->ni_vp = NULL;
-       error = VOP_LOOKUP(searchdir, &ndp->ni_vp, cnp);
+       foundobj = NULL;
+       error = VOP_LOOKUP(searchdir, &foundobj, cnp);
        if (error != 0) {
 #ifdef DIAGNOSTIC
-               if (ndp->ni_vp != NULL)
+               if (foundobj != NULL)
                        panic("leaf `%s' should be empty", cnp->cn_nameptr);
 #endif /* DIAGNOSTIC */
 #ifdef NAMEI_DIAGNOSTIC
@@ -981,11 +980,13 @@
                }
 
                /*
-                * We return with ni_vp NULL to indicate that the entry
+                * We return with foundobj NULL to indicate that the entry
                 * doesn't currently exist, leaving a pointer to the
                 * (possibly locked) directory vnode in ndp->ni_dvp.
                 */
                state->lookup_alldone = 1;
+               ndp->ni_dvp = searchdir;
+               ndp->ni_vp = NULL;
                *foundobj_ret = NULL;
                return (0);
        }
@@ -1006,10 +1007,8 @@
                        cnp->cn_flags |= ISLASTCN;
        }
 
-       foundobj = ndp->ni_vp;
-
        /*
-        * "foundobj" and "ndp->ni_dvp" are both locked and held,
+        * "foundobj" and "searchdir" are both locked and held,
         * and may be the same vnode.
         */
 
@@ -1024,21 +1023,23 @@
                        vput(foundobj);
                        return error;
                }
-               KASSERT(ndp->ni_dvp != foundobj);
-               VOP_UNLOCK(ndp->ni_dvp);
+               KASSERT(searchdir != foundobj);
+               VOP_UNLOCK(searchdir);
                vput(foundobj);
                error = VFS_ROOT(mp, &tdp);
                vfs_unbusy(mp, false, NULL);
                if (error) {
-                       vn_lock(ndp->ni_dvp, LK_EXCLUSIVE | LK_RETRY);
+                       vn_lock(searchdir, LK_EXCLUSIVE | LK_RETRY);
                        return error;
                }
                VOP_UNLOCK(tdp);
-               ndp->ni_vp = foundobj = tdp;
-               vn_lock(ndp->ni_dvp, LK_EXCLUSIVE | LK_RETRY);
-               vn_lock(ndp->ni_vp, LK_EXCLUSIVE | LK_RETRY);
+               foundobj = tdp;
+               vn_lock(searchdir, LK_EXCLUSIVE | LK_RETRY);
+               vn_lock(foundobj, LK_EXCLUSIVE | LK_RETRY);
        }
 
+       ndp->ni_dvp = searchdir;
+       ndp->ni_vp = foundobj;
        *foundobj_ret = foundobj;
        return 0;
 }