NFS4_READDIR
case NFS4_READDIR:
} else if (args->a_io == NFS4_READDIR) {
args->a_io = NFS4_READDIR;
if (mi->mi_async_reqs[NFS4_READDIR] == NULL) {
mi->mi_async_reqs[NFS4_READDIR] = args;
mi->mi_async_tail[NFS4_READDIR] = args;
mi->mi_async_tail[NFS4_READDIR]->a_next = args;
mi->mi_async_tail[NFS4_READDIR] = args;