On 04/06/2017 12:14 PM, Kevin Wolf wrote:
> Like in the mirror filter driver, we also need to set the image size for
> the commit filter driver. This is less likely to be a problem in
> practice than for the mirror because we're not at the active layer here,
> but attaching new parents to a node in the middle of the chain is
> possible, so the size needs to be correct anyway.
> 
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>  block/commit.c | 1 +
>  1 file changed, 1 insertion(+)

Reviewed-by: Eric Blake <eblake@redhat.com>

> 
> diff --git a/block/commit.c b/block/commit.c
> index 4c38220..91d2c34 100644
> --- a/block/commit.c
> +++ b/block/commit.c
> @@ -335,6 +335,7 @@ void commit_start(const char *job_id, BlockDriverState *bs,
>      if (commit_top_bs == NULL) {
>          goto fail;
>      }
> +    commit_top_bs->total_sectors = top->total_sectors;

[I'd really like to change total_sectors to bytes in 2.10 or later, but
that's a much hairier mess to untangle. I've got some patches that I
hope to post soon that at least start the process with regards to
bdrv_is_allocated...]

-- 
Eric Blake   eblake redhat com    +1-919-301-3266
Libvirt virtualization library http://libvirt.org