NFS: load the rpc/rdma transport module automatically

When mounting an NFS/RDMA server with the "-o proto=rdma" or
"-o rdma" options, attempt to dynamically load the necessary
"xprtrdma" client transport module. Doing so improves usability,
while avoiding a static module dependency and any unnecesary
resources.

Signed-off-by: Tom Talpey <tmtalpey@gmail.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index d6686f4786dc..0942fcbbad3c 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -1018,6 +1018,7 @@ static int nfs_parse_mount_options(char *raw,
                 case Opt_rdma:
                         mnt->flags |= NFS_MOUNT_TCP; /* for side protocols */
                         mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
+                        xprt_load_transport(p);
                         break;
                 case Opt_acl:
                         mnt->flags &= ~NFS_MOUNT_NOACL;
@@ -1205,12 +1206,14 @@ static int nfs_parse_mount_options(char *raw,
                                 /* vector side protocols to TCP */
                                 mnt->flags |= NFS_MOUNT_TCP;
                                 mnt->nfs_server.protocol = XPRT_TRANSPORT_RDMA;
+                                xprt_load_transport(string);
                                 break;
                         default:
                                 errors++;
                                 dfprintk(MOUNT, "NFS:   unrecognized "
                                                 "transport protocol\n");
                         }
+                        kfree(string);
                         break;
                 case Opt_mountproto:
                         string = match_strdup(args);
@@ -1218,7 +1221,6 @@ static int nfs_parse_mount_options(char *raw,
                                 goto out_nomem;
                         token = match_token(string,
                                             nfs_xprt_protocol_tokens, args);
-                        kfree(string);
 
                         switch (token) {
                         case Opt_xprt_udp: