NFS: Save the value of the "port=" mount option
During a remount based on the mount options displayed in /proc/mounts, we
want to preserve the original behavior of the mount request. Let's save
the original setting of the "port=" mount option in the mount's nfs_server
structure.
This allows us to simplify the default behavior of port setting for NFSv4
mounts: by default, NFSv2/3 mounts first try an RPC bind to determine the
NFS server's port, unless the user specified the "port=" mount option;
Users can force the client to skip the RPC bind by explicitly specifying
"port=<value>".
NFSv4, by contrast, assumes the NFS server port is 2049 and skips the RPC
bind, unless the user specifies "port=". Users can force an RPC bind for
NFSv4 by explicitly specifying "port=0".
I added a couple of extra comments to clarify this behavior.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 3423c67..670e5c7 100644
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -93,6 +93,7 @@
unsigned int wpages; /* write size (in pages) */
unsigned int wtmult; /* server disk block size */
unsigned int dtsize; /* readdir size */
+ unsigned short port; /* "port=" setting */
unsigned int bsize; /* server block size */
unsigned int acregmin; /* attr cache timeouts */
unsigned int acregmax;