In some examples, data integrity verification may include obtaining, from an application for which data is stored in a primary storage volume, an identification of data blocks of the primary storage volume that are stored for the application in a snapshot storage volume that represents a snapshot of data stored in the primary storage volume. The identification may include references to locations of the data blocks in the primary storage volume. Using physical extent mappings and volume block addressing, the identified locations of the data blocks in the primary storage volume may be translated to locations of snapshot storage volume blocks of the snapshot storage volume. Based on the snapshot storage volume blocks that are read from the snapshot storage volume, integrity of corresponding backup copy blocks stored in a backup copy for backup of the primary storage volume may be verified.