nfs4_proc_setclientid
status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);
extern int nfs4_proc_setclientid(struct nfs_client *, u32, unsigned short, const struct cred *, struct nfs4_setclientid_res *);
status = nfs4_proc_setclientid(clp, NFS4_CALLBACK, port, cred, &clid);