Definition identity_rmap' : R.rmap' := exist valid (fun _: AV.address => R.NO) AV.valid_empty.Definition identity_rmap (n:nat) : rmap := R.squash (n, identity_rmap').

Lemma make_rmap (f: AV.address -> resource) (V: AV.valid (res_option oo f)) (n: nat) (H: resource_fmap (approx n) oo f = f) : {phi: rmap | level phi = n /\ resource_at phi = f}.