From: Steve Dickson <SteveD@redhat.com>
Subject: [RHEL5.1][PATCH] add nordirplus option to NFS client 
Date: Thu, 17 May 2007 13:50:26 -0400
Bugzilla: 240126
Message-Id: <464C95E2.8090502@RedHat.com>
Changelog: [nfs] add nordirplus option to NFS client 


This upstream patch is the result of the Tru64 NFS server
being severely broken when it comes to maintaining
consistent FSIDs on Advfs filesystems.

Its seems the fsids that are returned in the READDIRPLUS
ops are different that the ones returned in the LOOKUP
ops which causes Linux clients to misinterpret the file
type. The reason other clients do have a similar problem,
is they appear to ignore the fsid that is returned,
something we did until the end of last year.

The bz is:
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=240126

steved.


commit 74dd34e6e8bb127ff4c182423154b294729b663b
Author: Steve Dickson <steved@redhat.com>

    NFS: Added support to turn off the NFSv3 READDIRPLUS RPC.
    
    READDIRPLUS can be a performance hindrance when the client is working with
    large directories. In addition, some servers still have bugs in their
    implementations (e.g. Tru64 returns wrong values for the fsid).
    
    Add a mount flag to enable users to turn it off at mount time following the
    implementation in Apple's NFS client.
    
    Signed-off-by: Steve Dickson <steved@redhat.com>
    Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

--- linux-2.6.18.i686/fs/nfs/client.c.orig	2007-05-17 09:09:46.209193000 -0400
+++ linux-2.6.18.i686/fs/nfs/client.c	2007-05-17 10:45:06.342871000 -0400
@@ -620,7 +620,8 @@ static int nfs_init_server(struct nfs_se
 	if (clp->cl_nfsversion == 3) {
 		if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
 			server->namelen = NFS3_MAXNAMLEN;
-		server->caps |= NFS_CAP_READDIRPLUS;
+		if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
+			server->caps |= NFS_CAP_READDIRPLUS;
 	} else {
 		if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
 			server->namelen = NFS2_MAXNAMLEN;
--- linux-2.6.18.i686/fs/nfs/super.c.orig	2007-05-17 09:09:32.066363000 -0400
+++ linux-2.6.18.i686/fs/nfs/super.c	2007-05-17 10:46:13.815953000 -0400
@@ -291,6 +291,7 @@ static void nfs_show_mount_options(struc
 		{ NFS_MOUNT_NONLM, ",nolock", "" },
 		{ NFS_MOUNT_NOACL, ",noacl", "" },
 		{ NFS_MOUNT_FSCACHE, ",fsc", "" },
+		{ NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" },
 		{ 0, NULL, NULL }
 	};
 	const struct proc_nfs_info *nfs_infop;
--- linux-2.6.18.i686/include/linux/nfs_mount.h.orig	2007-05-17 09:09:31.385431000 -0400
+++ linux-2.6.18.i686/include/linux/nfs_mount.h	2007-05-17 10:47:08.936730000 -0400
@@ -62,6 +62,7 @@ struct nfs_mount_data {
 #define NFS_MOUNT_STRICTLOCK	0x1000	/* reserved for NFSv4 */
 #define NFS_MOUNT_SECFLAVOUR	0x2000	/* 5 */
 #define NFS_MOUNT_FSCACHE	0x4000
+#define NFS_MOUNT_NORDIRPLUS	0x8000	/* 5 */
 #define NFS_MOUNT_FLAGMASK	0xFFFF
 
 #endif