[PATCH] update NFS/RDMA documentation

[James Lentini <jlentini@netapp.com>]

Bruce,

Below is an update to the NFS/RDMA documentation that clarifies how to 
run mount.nfs and addresses comments from you and Chuck. Could you 
please merge this for 2.6.26?

Signed-off-by: James Lentini <jlentini@netapp.com>

--- a/Documentation/filesystems/nfs-rdma.txt	2008-05-30 16:03:01.414533000 -0400
+++ a/Documentation/filesystems/nfs-rdma.txt	2008-06-02 15:26:51.138344000 -0400
@@ -5,7 +5,7 @@
 ################################################################################
 
  Author: NetApp and Open Grid Computing
- Date: April 15, 2008
+ Date: May 29, 2008
 
 Table of Contents
 ~~~~~~~~~~~~~~~~~
@@ -60,16 +60,18 @@ Installation
     The procedures described in this document have been tested with
     distributions from Red Hat's Fedora Project (http://fedora.redhat.com/).
 
-  - Install nfs-utils-1.1.1 or greater on the client
+  - Install nfs-utils-1.1.2 or greater on the client
 
-    An NFS/RDMA mount point can only be obtained by using the mount.nfs
-    command in nfs-utils-1.1.1 or greater. To see which version of mount.nfs
-    you are using, type:
+    An NFS/RDMA mount point can be obtained by using the mount.nfs command in
+    nfs-utils-1.1.2 or greater (nfs-utils-1.1.1 was the first nfs-utils version
+    with support for NFS/RDMA mounts, but for various reasons we recommend using
+    nfs-utils-1.1.2 or greater). To see which version of mount.nfs you are
+    using, type:
 
-    > /sbin/mount.nfs -V
+    $ /sbin/mount.nfs -V
 
-    If the version is less than 1.1.1 or the command does not exist,
-    then you will need to install the latest version of nfs-utils.
+    If the version is less than 1.1.2 or the command does not exist,
+    you should install the latest version of nfs-utils.
 
     Download the latest package from:
 
@@ -77,22 +79,32 @@ Installation
 
     Uncompress the package and follow the installation instructions.
 
-    If you will not be using GSS and NFSv4, the installation process
-    can be simplified by disabling these features when running configure:
+    If you will not need the idmapper and gssd executables (you do not need
+    these to create an NFS/RDMA enabled mount command), the installation
+    process can be simplified by disabling these features when running
+    configure:
 
-    > ./configure --disable-gss --disable-nfsv4
+    $ ./configure --disable-gss --disable-nfsv4
 
-    For more information on this see the package's README and INSTALL files.
+    To build nfs-utils you will need the tcp_wrappers package installed. For
+    more information on this see the package's README and INSTALL files.
 
     After building the nfs-utils package, there will be a mount.nfs binary in
     the utils/mount directory. This binary can be used to initiate NFS v2, v3,
     or v4 mounts. To initiate a v4 mount, the binary must be called mount.nfs4.
     The standard technique is to create a symlink called mount.nfs4 to mount.nfs.
 
-    NOTE: mount.nfs and therefore nfs-utils-1.1.1 or greater is only needed
+    This mount.nfs binary should be installed at /sbin/mount.nfs as follows:
+
+    $ sudo cp utils/mount/mount.nfs /sbin/mount.nfs
+
+    In this location, mount.nfs will be invoked automatically for NFS mounts
+    by the system mount commmand.
+
+    NOTE: mount.nfs and therefore nfs-utils-1.1.2 or greater is only needed
     on the NFS client machine. You do not need this specific version of
     nfs-utils on the server. Furthermore, only the mount.nfs command from
-    nfs-utils-1.1.1 is needed on the client.
+    nfs-utils-1.1.2 is needed on the client.
 
   - Install a Linux kernel with NFS/RDMA
 
@@ -156,8 +168,8 @@ Check RDMA and NFS Setup
     this time. For example, if you are using a Mellanox Tavor/Sinai/Arbel
     card:
 
-    > modprobe ib_mthca
-    > modprobe ib_ipoib
+    $ modprobe ib_mthca
+    $ modprobe ib_ipoib
 
     If you are using InfiniBand, make sure there is a Subnet Manager (SM)
     running on the network. If your IB switch has an embedded SM, you can
@@ -166,7 +178,7 @@ Check RDMA and NFS Setup
 
     If an SM is running on your network, you should see the following:
 
-    > cat /sys/class/infiniband/driverX/ports/1/state
+    $ cat /sys/class/infiniband/driverX/ports/1/state
     4: ACTIVE
 
     where driverX is mthca0, ipath5, ehca3, etc.
@@ -174,10 +186,10 @@ Check RDMA and NFS Setup
     To further test the InfiniBand software stack, use IPoIB (this
     assumes you have two IB hosts named host1 and host2):
 
-    host1> ifconfig ib0 a.b.c.x
-    host2> ifconfig ib0 a.b.c.y
-    host1> ping a.b.c.y
-    host2> ping a.b.c.x
+    host1$ ifconfig ib0 a.b.c.x
+    host2$ ifconfig ib0 a.b.c.y
+    host1$ ping a.b.c.y
+    host2$ ping a.b.c.x
 
     For other device types, follow the appropriate procedures.
 
@@ -214,9 +226,9 @@ NFS/RDMA Setup
 
     For InfiniBand using a Mellanox adapter:
 
-    > modprobe ib_mthca
-    > modprobe ib_ipoib
-    > ifconfig ib0 a.b.c.d
+    $ modprobe ib_mthca
+    $ modprobe ib_ipoib
+    $ ifconfig ib0 a.b.c.d
 
     NOTE: use unique addresses for the client and server
 
@@ -225,30 +237,31 @@ NFS/RDMA Setup
     If the NFS/RDMA server was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in kernel config),
     load the RDMA transport module:
 
-    > modprobe svcrdma
+    $ modprobe svcrdma
 
     Regardless of how the server was built (module or built-in), start the server:
 
-    > /etc/init.d/nfs start
+    $ /etc/init.d/nfs start
 
     or
 
-    > service nfs start
+    $ service nfs start
 
     Instruct the server to listen on the RDMA transport:
 
-    > echo rdma 2050 > /proc/fs/nfsd/portlist
+    $ echo rdma 2050 > /proc/fs/nfsd/portlist
 
   - On the client system
 
     If the NFS/RDMA client was built as a module (CONFIG_SUNRPC_XPRT_RDMA=m in kernel config),
     load the RDMA client module:
 
-    > modprobe xprtrdma.ko
+    $ modprobe xprtrdma.ko
 
-    Regardless of how the client was built (module or built-in), issue the mount.nfs command:
+    Regardless of how the client was built (module or built-in), use this command to 
+    mount the NFS/RDMA server:
 
-    > /path/to/your/mount.nfs <IPoIB-server-name-or-address>:/<export> /mnt -i -o rdma,port=2050
+    $ mount -o rdma,port=2050 <IPoIB-server-name-or-address>:/<export> /mnt
 
     To verify that the mount is using RDMA, run "cat /proc/mounts" and check the
     "proto" field for the given mount.