Preheat oven to 375 degrees F.
In a medium bowl, combine cheeses, olives, and Italian seasoning. On a floured surface, unroll crescent dough in 1 piece. Roll out to a 16 by 8-inch rectangle. Using a pizza cutter, slice into 8 (4 by 4-inch) squares. Place 2 tablespoons of filling on half of each square. Lightly moisten the edges with water, fold dough over, and seal, pressing with fork tines. Using the points of the fork, pierce vents into top of each calzone. Place on a greased baking sheet and bake for 20 minutes or until golden. Serve hot.