NFS4_MAXPATHLEN
c = strndup_user(data->mnt_path.data, NFS4_MAXPATHLEN);
max_pathlen = NFS4_MAXPATHLEN;
if (len > NFS4_MAXPATHLEN)
#define nfs4_path_maxsz (1 + ((3 + NFS4_MAXPATHLEN) >> 2))