diff -u --recursive --new-file linux-2.6.0-21-sock_disconnect/fs/nfs/dir.c linux-2.6.0-22-atomic_open1/fs/nfs/dir.c
--- linux-2.6.0-21-sock_disconnect/fs/nfs/dir.c	2003-11-10 12:50:27.000000000 -0500
+++ linux-2.6.0-22-atomic_open1/fs/nfs/dir.c	2003-11-11 02:28:01.000000000 -0500
@@ -72,6 +72,26 @@
 	.setattr	= nfs_setattr,
 };
 
+#ifdef CONFIG_NFS_V4
+
+static struct dentry *nfs_atomic_lookup(struct inode *, struct dentry *, struct nameidata *);
+struct inode_operations nfs4_dir_inode_operations = {
+	.create		= nfs_create,
+	.lookup		= nfs_atomic_lookup,
+	.link		= nfs_link,
+	.unlink		= nfs_unlink,
+	.symlink	= nfs_symlink,
+	.mkdir		= nfs_mkdir,
+	.rmdir		= nfs_rmdir,
+	.mknod		= nfs_mknod,
+	.rename		= nfs_rename,
+	.permission	= nfs_permission,
+	.getattr	= nfs_getattr,
+	.setattr	= nfs_setattr,
+};
+
+#endif /* CONFIG_NFS_V4 */
+
 /*
  * Open file
  */
@@ -670,7 +690,7 @@
 		goto out;
 
 	error = -ENOMEM;
-	dentry->d_op = &nfs_dentry_operations;
+	dentry->d_op = NFS_PROTO(dir)->dentry_ops;
 
 	lock_kernel();
 
@@ -702,6 +722,57 @@
 	return ERR_PTR(error);
 }
 
+#ifdef CONFIG_NFS_V4
+/*
+ * FIXME:
+ * 	We need to funnel all NFSv4 lookups through nfs_lookup(), since
+ * 	NFSv4 OPEN calls are not idempotent.
+ * 	We still want to be able to cache dentries in the dcache though.
+ *
+ * 	Hack: Hide the cached dentries from the VFS by allowing
+ * 	d_lookup() to find files iff string length is negative.
+ */
+static int nfs_dentry_compare(struct dentry *parent, struct qstr *qstr,
+		struct qstr *name)
+{
+	int len = -name->len;
+
+	if (qstr->len != len)
+		return -1;
+	return memcmp(qstr->name, name->name, len);
+}
+
+struct dentry_operations nfs4_dentry_operations = {
+	.d_revalidate	= nfs_lookup_revalidate,
+	.d_compare	= nfs_dentry_compare,
+	.d_delete	= nfs_dentry_delete,
+	.d_iput		= nfs_dentry_iput,
+};
+
+static struct dentry *nfs_dcache_lookup(struct dentry *parent, struct qstr *qstr)
+{
+	struct qstr name = {
+		.len = -qstr->len,
+		.name = qstr->name,
+		.hash = qstr->hash
+	};
+	return d_lookup(parent, &name);
+}
+
+static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+{
+	struct dentry *cached;
+
+	cached = nfs_dcache_lookup(dentry->d_parent, &dentry->d_name);
+	if (cached != NULL) {
+		if (nfs_lookup_revalidate(cached, nd))
+			return cached;
+		dput(cached);
+	}
+	return nfs_lookup(dir, dentry, nd);
+}
+#endif /* CONFIG_NFSV4 */
+
 static inline
 int find_dirent_name(nfs_readdir_descriptor_t *desc, struct page *page, struct dentry *dentry)
 {
diff -u --recursive --new-file linux-2.6.0-21-sock_disconnect/fs/nfs/inode.c linux-2.6.0-22-atomic_open1/fs/nfs/inode.c
--- linux-2.6.0-21-sock_disconnect/fs/nfs/inode.c	2003-11-10 18:49:40.000000000 -0500
+++ linux-2.6.0-22-atomic_open1/fs/nfs/inode.c	2003-11-10 18:48:49.000000000 -0500
@@ -312,7 +312,7 @@
 	if (!sb->s_root)
 		goto out_no_root;
 
-	sb->s_root->d_op = &nfs_dentry_operations;
+	sb->s_root->d_op = server->rpc_ops->dentry_ops;
 
 	/* Get some general file system info */
         if (server->rpc_ops->fsinfo(server, &server->fh, &fsinfo) < 0) {
@@ -745,7 +745,7 @@
 			inode->i_data.a_ops = &nfs_file_aops;
 			inode->i_data.backing_dev_info = &NFS_SB(sb)->backing_dev_info;
 		} else if (S_ISDIR(inode->i_mode)) {
-			inode->i_op = &nfs_dir_inode_operations;
+			inode->i_op = NFS_SB(sb)->rpc_ops->dir_inode_ops;
 			inode->i_fop = &nfs_dir_operations;
 			if (nfs_server_capable(inode, NFS_CAP_READDIRPLUS)
 			    && fattr->size <= NFS_LIMIT_READDIRPLUS)
diff -u --recursive --new-file linux-2.6.0-21-sock_disconnect/fs/nfs/nfs3proc.c linux-2.6.0-22-atomic_open1/fs/nfs/nfs3proc.c
--- linux-2.6.0-21-sock_disconnect/fs/nfs/nfs3proc.c	2003-11-10 12:50:28.000000000 -0500
+++ linux-2.6.0-22-atomic_open1/fs/nfs/nfs3proc.c	2003-11-10 16:10:27.000000000 -0500
@@ -898,6 +898,8 @@
 
 struct nfs_rpc_ops	nfs_v3_clientops = {
 	.version	= 3,			/* protocol version */
+	.dentry_ops	= &nfs_dentry_operations,
+	.dir_inode_ops	= &nfs_dir_inode_operations,
 	.getroot	= nfs3_proc_get_root,
 	.getattr	= nfs3_proc_getattr,
 	.setattr	= nfs3_proc_setattr,
diff -u --recursive --new-file linux-2.6.0-21-sock_disconnect/fs/nfs/nfs4proc.c linux-2.6.0-22-atomic_open1/fs/nfs/nfs4proc.c
--- linux-2.6.0-21-sock_disconnect/fs/nfs/nfs4proc.c	2003-11-10 13:04:02.000000000 -0500
+++ linux-2.6.0-22-atomic_open1/fs/nfs/nfs4proc.c	2003-11-10 16:10:22.000000000 -0500
@@ -1922,6 +1922,8 @@
 
 struct nfs_rpc_ops	nfs_v4_clientops = {
 	.version	= 4,			/* protocol version */
+	.dentry_ops	= &nfs4_dentry_operations,
+	.dir_inode_ops	= &nfs4_dir_inode_operations,
 	.getroot	= nfs4_proc_get_root,
 	.getattr	= nfs4_proc_getattr,
 	.setattr	= nfs4_proc_setattr,
diff -u --recursive --new-file linux-2.6.0-21-sock_disconnect/fs/nfs/proc.c linux-2.6.0-22-atomic_open1/fs/nfs/proc.c
--- linux-2.6.0-21-sock_disconnect/fs/nfs/proc.c	2003-11-10 12:53:56.000000000 -0500
+++ linux-2.6.0-22-atomic_open1/fs/nfs/proc.c	2003-11-10 16:10:06.000000000 -0500
@@ -656,6 +656,8 @@
 
 struct nfs_rpc_ops	nfs_v2_clientops = {
 	.version	= 2,		       /* protocol version */
+	.dentry_ops	= &nfs_dentry_operations,
+	.dir_inode_ops	= &nfs_dir_inode_operations,
 	.getroot	= nfs_proc_get_root,
 	.getattr	= nfs_proc_getattr,
 	.setattr	= nfs_proc_setattr,
diff -u --recursive --new-file linux-2.6.0-21-sock_disconnect/include/linux/nfs_fs.h linux-2.6.0-22-atomic_open1/include/linux/nfs_fs.h
--- linux-2.6.0-21-sock_disconnect/include/linux/nfs_fs.h	2003-11-10 13:03:19.000000000 -0500
+++ linux-2.6.0-22-atomic_open1/include/linux/nfs_fs.h	2003-11-10 17:51:19.000000000 -0500
@@ -559,6 +559,9 @@
 };
 
 
+extern struct dentry_operations nfs4_dentry_operations;
+extern struct inode_operations nfs4_dir_inode_operations;
+
 /* nfs4proc.c */
 extern int nfs4_proc_setclientid(struct nfs4_client *, u32, unsigned short);
 extern int nfs4_proc_setclientid_confirm(struct nfs4_client *);
diff -u --recursive --new-file linux-2.6.0-21-sock_disconnect/include/linux/nfs_xdr.h linux-2.6.0-22-atomic_open1/include/linux/nfs_xdr.h
--- linux-2.6.0-21-sock_disconnect/include/linux/nfs_xdr.h	2003-11-10 13:02:38.000000000 -0500
+++ linux-2.6.0-22-atomic_open1/include/linux/nfs_xdr.h	2003-11-10 17:50:05.000000000 -0500
@@ -637,6 +637,8 @@
  */
 struct nfs_rpc_ops {
 	int	version;		/* Protocol version */
+	struct dentry_operations *dentry_ops;
+	struct inode_operations *dir_inode_ops;
 
 	int	(*getroot) (struct nfs_server *, struct nfs_fh *,
 			    struct nfs_fattr *);