Definition getMaxPerm (m : mem) : access_map :=
    Maps.PMap.map (fun f => fun ofs => f ofs Max) (Mem.mem_access m).Definition getCurPerm (m : mem) : access_map :=
    Maps.PMap.map (fun f => fun ofs => f ofs Cur) (Mem.mem_access m).Definition getPermMap (m : mem) : Maps.PMap.t (Z -> perm_kind -> option permission) :=
    Mem.mem_access m.

Lemma getMaxPerm_correct : forall m b ofs, Maps.PMap.get b (getMaxPerm m) ofs = permission_at m b ofs Max.