On Mon, 04/29 09:42, Stefan Hajnoczi wrote:
> +
> +static void coroutine_fn backup_run(void *opaque)
> +{
> + BackupBlockJob *job = opaque;
> + BlockDriverState *bs = job->common.bs;
> + assert(bs);
> +
> + int64_t start, end;
> +
> + start = 0;
> + end = DIV_ROUND_UP(bdrv_getlength(bs) / BDRV_SECTOR_SIZE,
> + BACKUP_BLOCKS_PER_CLUSTER);
> +
> + job->bitmap = hbitmap_alloc(end, 0);
> +
> + DPRINTF("backup_run start %s %" PRId64 " %" PRId64 "\n",
> + bdrv_get_device_name(bs), start, end);
> +
> + int ret = 0;
> +
> + for (; start < end; start++) {
> + if (block_job_is_cancelled(&job->common)) {
> + ret = -1;
> + break;
> + }
> +
> + /* we need to yield so that qemu_aio_flush() returns.
> + * (without, VM does not reboot)
> + */
> + if (job->common.speed) {
> + uint64_t delay_ns = ratelimit_calculate_delay(
> + &job->limit, job->sectors_read);
> + job->sectors_read = 0;
> + block_job_sleep_ns(&job->common, rt_clock, delay_ns);
> + } else {
> + block_job_sleep_ns(&job->common, rt_clock, 0);
> + }
> +
> + if (block_job_is_cancelled(&job->common)) {
> + ret = -1;
> + break;
> + }
> +
> + if (hbitmap_get(job->bitmap, start)) {
> + continue; /* already copied */
> + }
> +
> + DPRINTF("backup_run loop C%" PRId64 "\n", start);
> +
> + /**
> + * This triggers a cluster copy
> + * Note: avoid direct call to brdv_co_backup_cow, because
> + * this does not call tracked_request_begin()
> + */
> + ret = bdrv_co_backup(bs, start*BACKUP_BLOCKS_PER_CLUSTER, 1);
> + if (ret < 0) {
> + break;
> + }
> + /* Publish progress */
> + job->common.offset += BACKUP_CLUSTER_SIZE;
> + }
> +
> + /* wait until pending backup_do_cow()calls have completed */
> + qemu_co_rwlock_wrlock(&job->rwlock);
> + qemu_co_rwlock_unlock(&job->rwlock);
> +
> + hbitmap_free(job->bitmap);
> +
> + bdrv_delete(job->target);
> +
> + DPRINTF("backup_run complete %d\n", ret);
> + block_job_completed(&job->common, ret);
> +}
What will ret value be when the source block is not aligned to cluster
size?
Fam
