Revert "more Mem->PhysMem, Obj->Mem"

This reverts commit fcbb33f163aee07b2a3b524604df4d0b902f8a9b.
Revert "more Mem->PhysMem, Obj->Mem"

This reverts commit 274ee990709349c4670b985c6cd39f80b0500505.
Revert "ObjectRequest -> MemRequest"

This reverts commit 9d68c34fb72dc658e466f71cb344784394075f44.