[src/trunk]: src/sys/fs/udf First step in rewriting the genealogy case

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

details:   https://anonhg.NetBSD.org/src/rev/12b55d57dba4
branches:  trunk
changeset: 787933:12b55d57dba4
user:      reinoud <reinoud%NetBSD.org@localhost>
date:      Mon Jul 15 14:40:21 2013 +0000

description:
First step in rewriting the genealogy case

diffstat:

 sys/fs/udf/udf_rename.c |  32 ++++++++++++++++++++++----------
 1 files changed, 22 insertions(+), 10 deletions(-)

diffs (63 lines):

diff -r 3d5a0e0e4988 -r 12b55d57dba4 sys/fs/udf/udf_rename.c
--- a/sys/fs/udf/udf_rename.c   Mon Jul 15 12:10:34 2013 +0000
+++ b/sys/fs/udf/udf_rename.c   Mon Jul 15 14:40:21 2013 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: udf_rename.c,v 1.8 2013/07/13 19:42:26 reinoud Exp $ */
+/* $NetBSD: udf_rename.c,v 1.9 2013/07/15 14:40:21 reinoud Exp $ */
 
 /*
  * Copyright (c) 2013 Reinoud Zandijk
@@ -28,7 +28,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: udf_rename.c,v 1.8 2013/07/13 19:42:26 reinoud Exp $");
+__KERNEL_RCSID(0, "$NetBSD: udf_rename.c,v 1.9 2013/07/15 14:40:21 reinoud Exp $");
 
 #include <sys/param.h>
 #include <sys/errno.h>
@@ -586,24 +586,36 @@
                        return 0;
                }
 
+               /*
+                * Unlock vp so that we can lock the parent, but keep child vp
+                * referenced until after we have found the parent, so that
+                * dotdot_ino will not be recycled.
+                *
+                * XXX This guarantees that vp's inode number will not be
+                * recycled, but why can't dotdot_ino be recycled?
+                */
                DPRINTF(NODE, ("\tgetting the parent node\n"));
+               VOP_UNLOCK(child_node->vnode);
                error = udf_get_node(ump, &parent_loc, &parent_node);
-               if (error) {
+               vrele(child_node->vnode);
+               if (error) 
+                       return error;
+
+               /* sanity check */
+               if (parent_node->vnode->v_type != VDIR) {
+                       /* 
+                        * Odd, but can happen if we loose the race and the
+                        * '..' node has been recycled.
+                        */
                        vput(child_node->vnode);
-                       return error;
+                       return ENOTDIR;
                }
 
                if (udf_rmdired_p(parent_node->vnode)) {
-                       vput(child_node->vnode);
                        vput(parent_node->vnode);
                        return ENOENT;
                }
 
-               /*
-                * Push our intermediate node, we're done with it, but do
-                * remember our parent location
-                */
-               vput(child_node->vnode);
                child_node = parent_node;
        }
 }