volcache_invalidate (fid.fid.Volume, fid.Cell);
viocflushvolume (int fd, struct xfs_message_pioctl *h, u_int size){    VenusFid fid ;    if (!h->handle.a && !h->handle.b && !h->handle.c && !h->handle.d)	return EINVAL;    fid.Cell = h->handle.a;    fid.fid.Volume = h->handle.b;    fid.fid.Vnode = 0;    fid.fid.Unique = 0;    arla_warnx(ADEBMSG,	       "flushing volume (%d, %u)",	       fid.Cell, fid.fid.Volume);    fcache_purge_volume(fid);    return 0 ;}