break;
             case PAYLOAD_BLOCK_FULLY_PRESENT:
                 qemu_co_mutex_unlock(&s->lock);
-                ret = bdrv_co_readv(bs->file,
-                                    sinfo.file_offset >> BDRV_SECTOR_BITS,
-                                    sinfo.sectors_avail, &hd_qiov);
+                ret = bdrv_co_preadv(bs->file, sinfo.file_offset,
+                                     sinfo.sectors_avail * BDRV_SECTOR_SIZE,
+                                     &hd_qiov, 0);
                 qemu_co_mutex_lock(&s->lock);
                 if (ret < 0) {
                     goto exit;
                 }
                 /* block exists, so we can just overwrite it */
                 qemu_co_mutex_unlock(&s->lock);
-                ret = bdrv_co_writev(bs->file,
-                                    sinfo.file_offset >> BDRV_SECTOR_BITS,
-                                    sectors_to_write, &hd_qiov);
+                ret = bdrv_co_pwritev(bs->file, sinfo.file_offset,
+                                      sectors_to_write * BDRV_SECTOR_SIZE,
+                                      &hd_qiov, 0);
                 qemu_co_mutex_lock(&s->lock);
                 if (ret < 0) {
                     goto error_bat_restore;