Re: [Qemu-devel] [PATCH 1/6] block: Add blocker on mirror target

[Max Reitz <mreitz@redhat.com>]

On 09.06.2015 04:13, Fam Zheng wrote:
> In block/backup.c, we already check and add blocker on the target bs,
> which is necessary so that it won't be intervened with other operations.
>
> In block/mirror.c we should also protect the mirror target bs, because it
> could have a node-name (drive-mirror ... node-name=XXX), and on top of
> that it's safe to add blockdev-mirror.
>
> Signed-off-by: Fam Zheng <famz@redhat.com>
> ---
>   block/mirror.c | 2 ++
>   1 file changed, 2 insertions(+)
>
> diff --git a/block/mirror.c b/block/mirror.c
> index 33c640f..8b23ddd 100644
> --- a/block/mirror.c
> +++ b/block/mirror.c
> @@ -360,6 +360,7 @@ static void mirror_exit(BlockJob *job, void *opaque)
>           aio_context_release(replace_aio_context);
>       }
>       g_free(s->replaces);
> +    bdrv_op_unblock_all(s->target, s->common.blocker);
>       bdrv_unref(s->target);
>       block_job_completed(&s->common, data->ret);
>       g_free(data);
> @@ -682,6 +683,7 @@ static void mirror_start_job(BlockDriverState *bs, BlockDriverState *target,
>           return;
>       }
>   
> +    bdrv_op_block_all(target, s->common.blocker);
>       s->replaces = g_strdup(replaces);
>       s->on_source_error = on_source_error;
>       s->on_target_error = on_target_error;

Do we need a bdrv_op_unblock_all() if bdrv_create_dirty_bitmap() fails?

Max