static int vpc_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) { BDRVVPCState *s = (BDRVVPCState *)bs->opaque; VHDFooter *footer = (VHDFooter *) s->footer_buf; if (cpu_to_be32(footer->type) != VHD_FIXED) { bdi->cluster_size = s->block_size; } bdi->unallocated_blocks_are_zero = true; return 0; }