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/fs/nfs/client.c b/fs/nfs/client.c
index 06f064d..8740181 100644 (file)
--- a/fs/nfs/client.c
+++ b/fs/nfs/client.c
@@ -682,6 +682,8 @@ static int nfs_init_server(struct nfs_server *server,
        if (error < 0)
                goto error;
 
+       server->port = data->nfs_server.port;
+
        error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
        if (error < 0)
                goto error;
@@ -1064,6 +1066,8 @@ static int nfs4_init_server(struct nfs_server *server,
        server->acdirmin = data->acdirmin * HZ;
        server->acdirmax = data->acdirmax * HZ;
 
+       server->port = data->nfs_server.port;
+
        error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
 
 error:

diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index e89688a..999ad8e 100644 (file)
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -56,6 +56,7 @@ struct nfs_parsed_mount_data {
                size_t                  addrlen;
                char                    *hostname;
                char                    *export_path;
+               unsigned short          port;
                unsigned short          protocol;
        } nfs_server;
 

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 53a67c6..3c6f53a 100644 (file)
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -685,7 +685,6 @@ static int nfs_parse_mount_options(char *raw,
                                   struct nfs_parsed_mount_data *mnt)
 {
        char *p, *string, *secdata;
-       unsigned short port = 0;
        int rc;
 
        if (!raw) {
@@ -800,7 +799,7 @@ static int nfs_parse_mount_options(char *raw,
                                return 0;
                        if (option < 0 || option > 65535)
                                return 0;
-                       port = option;
+                       mnt->nfs_server.port = option;
                        break;
                case Opt_rsize:
                        if (match_int(args, &mnt->rsize))
@@ -1050,7 +1049,8 @@ static int nfs_parse_mount_options(char *raw,
                }
        }
 
-       nfs_set_port((struct sockaddr *)&mnt->nfs_server.address, port);
+       nfs_set_port((struct sockaddr *)&mnt->nfs_server.address,
+                               mnt->nfs_server.port);
 
        return 1;
 
@@ -1171,7 +1171,9 @@ static int nfs_validate_mount_data(void *options,
        args->acregmax          = 60;
        args->acdirmin          = 30;
        args->acdirmax          = 60;
+       args->mount_server.port = 0;    /* autobind unless user sets port */
        args->mount_server.protocol = XPRT_TRANSPORT_UDP;
+       args->nfs_server.port   = 0;    /* autobind unless user sets port */
        args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 
        switch (data->version) {
@@ -1708,28 +1710,6 @@ static void nfs4_fill_super(struct super_block *sb)
 }
 
 /*
- * If the user didn't specify a port, set the port number to
- * the NFS version 4 default port.
- */
-static void nfs4_default_port(struct sockaddr *sap)
-{
-       switch (sap->sa_family) {
-       case AF_INET: {
-               struct sockaddr_in *ap = (struct sockaddr_in *)sap;
-               if (ap->sin_port == 0)
-                       ap->sin_port = htons(NFS_PORT);
-               break;
-       }
-       case AF_INET6: {
-               struct sockaddr_in6 *ap = (struct sockaddr_in6 *)sap;
-               if (ap->sin6_port == 0)
-                       ap->sin6_port = htons(NFS_PORT);
-               break;
-       }
-       }
-}
-
-/*
  * Validate NFSv4 mount options
  */
 static int nfs4_validate_mount_data(void *options,
@@ -1753,6 +1733,7 @@ static int nfs4_validate_mount_data(void *options,
        args->acregmax          = 60;
        args->acdirmin          = 30;
        args->acdirmax          = 60;
+       args->nfs_server.port   = NFS_PORT; /* 2049 unless user set port= */
        args->nfs_server.protocol = XPRT_TRANSPORT_TCP;
 
        switch (data->version) {
@@ -1769,9 +1750,6 @@ static int nfs4_validate_mount_data(void *options,
                                                &args->nfs_server.address))
                        goto out_no_address;
 
-               nfs4_default_port((struct sockaddr *)
-                                 &args->nfs_server.address);
-
                switch (data->auth_flavourlen) {
                case 0:
                        args->auth_flavors[0] = RPC_AUTH_UNIX;
@@ -1829,9 +1807,6 @@ static int nfs4_validate_mount_data(void *options,
                                                &args->nfs_server.address))
                        return -EINVAL;
 
-               nfs4_default_port((struct sockaddr *)
-                                 &args->nfs_server.address);
-
                switch (args->auth_flavor_len) {
                case 0:
                        args->auth_flavors[0] = RPC_AUTH_UNIX;

diff --git a/include/linux/nfs_fs_sb.h b/include/linux/nfs_fs_sb.h
index 3423c67..670e5c7 100644 (file)
--- a/include/linux/nfs_fs_sb.h
+++ b/include/linux/nfs_fs_sb.h
@@ -93,6 +93,7 @@ struct nfs_server {
        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;