- if (n < cluster_sectors) {
- memset(buf + n * 512, 0, cluster_size - n * 512);
- }
- if (!buffer_is_zero(buf, cluster_size)) {
- ret = bdrv_write_compressed(out_bs, sector_num, buf,
- cluster_sectors);
+ if (!buffer_is_zero(buf, n * BDRV_SECTOR_SIZE)) {
+ ret = bdrv_write_compressed(out_bs, sector_num, buf, n);