Preheat the oven to 425 degrees. Line 2 baking sheets with parchment paper. Roll out the pizza dough on a lightly floured surface into a 12-by-16-inch rectangle. Cut into 6-by-8-inch quarters, then cut each quarter in half diagonally to make 8 triangles.
Brush each triangle of dough with marinara sauce, leaving a 1/2-inch border all around; sprinkle with mozzarella and parmesan (reserve some of the sauce and cheese for topping). Layer a few pieces of pepperoni, olives and/or mushrooms over the cheese, reserving a few pieces for topping. Slightly fold in the two far corners, then roll up the dough from the long side, like a burrito, until the filling is fully enclosed in a tube, pressing gently to seal.
Carefully insert a popsicle stick or wooden skewer into the center of each pizza roll and arrange on the prepared baking sheets. Brush the rolls with olive oil and more marinara sauce; sprinkle with garlic, oregano and red pepper flakes. Press any extra filling ingredients onto the rolls. Sprinkle with more mozzarella and parmesan. Bake until golden, about 20 minutes.