Re: [PATCH v3 2/2] qemu-img: map: report compressed data blocks

[Eric Blake]

On Fri, Sep 08, 2023 at 12:02:26AM +0300, Andrey Drobyshev wrote:
> Right now "qemu-img map" reports compressed blocks as containing data
> but having no host offset.  This is not very informative.  Instead,
> let's add another boolean field named "compressed" in case JSON output
> mode is specified.  This is achieved by utilizing new allocation status
> flag BDRV_BLOCK_COMPRESSED for bdrv_block_status().
> 
> Also update the expected qemu-iotests outputs to contain the new field.
> 
> Signed-off-by: Andrey Drobyshev <andrey.drobyshev@virtuozzo.com>
> ---

> +++ b/qapi/block-core.json
> @@ -409,6 +409,9 @@
>  #
>  # @zero: whether the virtual blocks read as zeroes
>  #
> +# @compressed: true indicates that data is stored compressed.  Only valid
> +#     for the formats whith support compression (since 8.2)

s/whith/which/

"compressed":false seems universally valid for all other file formats,
and the field is not marked as optional.  Do we really need the
disclaimer?  Could we get by with the shorter 'Will be false for
formats that do not support compression', or by omitting it
altogether?

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.
Virtualization:  qemu.org | libguestfs.org