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

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

details:   https://anonhg.NetBSD.org/src/rev/15386575c325
branches:  trunk
changeset: 764071:15386575c325
user:      dholland <dholland%NetBSD.org@localhost>
date:      Mon Apr 11 02:15:54 2011 +0000

description:
description:
Don't assign ni_dvp until the end of namei_oneroot().

diffstat:

 sys/kern/vfs_lookup.c |  64 +++++++++++++++++++++++++++-----------------------
 1 files changed, 35 insertions(+), 29 deletions(-)

diffs (164 lines):

diff -r 1d766befefdb -r 15386575c325 sys/kern/vfs_lookup.c
--- a/sys/kern/vfs_lookup.c     Mon Apr 11 02:15:38 2011 +0000
+++ b/sys/kern/vfs_lookup.c     Mon Apr 11 02:15:54 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_lookup.c,v 1.156 2011/04/11 02:15:38 dholland Exp $        */
+/*     $NetBSD: vfs_lookup.c,v 1.157 2011/04/11 02:15:54 dholland Exp $        */
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1993
@@ -37,7 +37,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_lookup.c,v 1.156 2011/04/11 02:15:38 dholland Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_lookup.c,v 1.157 2011/04/11 02:15:54 dholland Exp $");
 
 #include "opt_magiclinks.h"
 
@@ -1107,6 +1107,7 @@
                 * current node.
                 */
                if (cnp->cn_nameptr[0] == '\0') {
+                       vref(searchdir);
                        foundobj = searchdir;
                        ndp->ni_vp = foundobj;
                        cnp->cn_flags |= ISLASTCN;
@@ -1141,8 +1142,9 @@
                        state->attempt_retry = 1;
                        return (error);
                }
-               ndp->ni_dvp = searchdir;
+               KASSERT(ndp->ni_dvp == NULL);
                ndp->ni_vp = foundobj;
+
                // XXX ought to be able to avoid this case too
                if (state->lookup_alldone) {
                        error = 0;
@@ -1175,9 +1177,10 @@
                                                     &searchdir);
                        }
                        if (error) {
-                               KASSERT(ndp->ni_dvp != ndp->ni_vp);
-                               vput(ndp->ni_dvp);
+                               KASSERT(searchdir != ndp->ni_vp);
+                               vput(searchdir);
                                vput(ndp->ni_vp);
+                               KASSERT(ndp->ni_dvp == NULL);
                                ndp->ni_vp = NULL;
                                return error;
                        }
@@ -1190,11 +1193,11 @@
                 * followed by a series of slashes.
                 */
                if ((foundobj->v_type != VDIR) && (cnp->cn_flags & REQUIREDIR)) {
-                       KASSERT(foundobj != ndp->ni_dvp);
+                       KASSERT(foundobj != searchdir);
                        vput(foundobj);
                        ndp->ni_vp = NULL;
-                       if (ndp->ni_dvp) {
-                               vput(ndp->ni_dvp);
+                       if (searchdir) {
+                               vput(searchdir);
                        }
                        state->attempt_retry = 1;
                        return ENOTDIR;
@@ -1207,13 +1210,14 @@
                 */
                if (!(cnp->cn_flags & ISLASTCN)) {
                        cnp->cn_nameptr = ndp->ni_next;
-                       if (ndp->ni_dvp == foundobj) {
-                               vrele(ndp->ni_dvp);
+                       if (searchdir == foundobj) {
+                               vrele(searchdir);
                        } else {
-                               vput(ndp->ni_dvp);
+                               vput(searchdir);
                        }
-                       ndp->ni_dvp = NULL;
+                       KASSERT(ndp->ni_dvp == NULL);
                        searchdir = foundobj;
+                       foundobj = NULL;
                        goto dirloop;
                }
 
@@ -1227,12 +1231,13 @@
                         * matches that returned for "/" and loop
                         * forever.  So convert it to the real root.
                         */
-                       if (ndp->ni_dvp == foundobj)
+                       if (searchdir == foundobj)
                                vrele(foundobj);
                        else
-                               if (ndp->ni_dvp != NULL)
-                                       vput(ndp->ni_dvp);
-                       ndp->ni_dvp = NULL;
+                               if (searchdir != NULL)
+                                       vput(searchdir);
+                       searchdir = NULL;
+                       KASSERT(ndp->ni_dvp == NULL);
                        vput(foundobj);
                        foundobj = ndp->ni_rootdir;
                        vref(foundobj);
@@ -1246,7 +1251,7 @@
                 * and we don't have one (because this is the
                 * root directory), then we must fail.
                 */
-               if (ndp->ni_dvp == NULL && cnp->cn_nameiop != LOOKUP) {
+               if (searchdir == NULL && cnp->cn_nameiop != LOOKUP) {
                        switch (cnp->cn_nameiop) {
                            case CREATE:
                                error = EEXIST;
@@ -1260,9 +1265,8 @@
                        }
                        vput(foundobj);
                        foundobj = NULL;
-                       if (ndp->ni_dvp) {
-                               vput(ndp->ni_dvp);
-                       }
+                       KASSERT(ndp->ni_dvp == NULL);
+                       ndp->ni_vp = NULL;
                        state->attempt_retry = 1;
                        return (error);
                }
@@ -1274,13 +1278,14 @@
                if (state->rdonly &&
                    (cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
                        error = EROFS;
-                       if (foundobj != ndp->ni_dvp) {
+                       if (foundobj != searchdir) {
                                vput(foundobj);
                        }
+                       if (searchdir) {
+                               vput(searchdir);
+                       }
+                       KASSERT(ndp->ni_dvp == NULL);
                        ndp->ni_vp = NULL;
-                       if (ndp->ni_dvp) {
-                               vput(ndp->ni_dvp);
-                       }
                        state->attempt_retry = 1;
                        return (error);
                }
@@ -1298,15 +1303,16 @@
        /*
         * If LOCKPARENT is not set, the parent directory isn't returned.
         */
-       if ((cnp->cn_flags & LOCKPARENT) == 0 && ndp->ni_dvp != NULL) {
-               if (ndp->ni_dvp == ndp->ni_vp) {
-                       vrele(ndp->ni_dvp);
+       if ((cnp->cn_flags & LOCKPARENT) == 0 && searchdir != NULL) {
+               if (searchdir == ndp->ni_vp) {
+                       vrele(searchdir);
                } else {
-                       vput(ndp->ni_dvp);
+                       vput(searchdir);
                }
-               ndp->ni_dvp = NULL;
+               searchdir = NULL;
        }
 
+       ndp->ni_dvp = searchdir;
        return 0;
 }