Re: [Qemu-devel] [PATCH for-2.12 01/12] vdi: Change 'static' create option to 'preallocation' in QMP

[Eric Blake <eblake@redhat.com>]

On 03/20/2018 12:36 PM, Kevin Wolf wrote:
> What static=on really does is what we call metadata preallocation for
> other block drivers. While we can still change the QMP interface, make
> it more consistent by using 'preallocation' for VDI, too.

The x- naming of the command means we don't HAVE to get this patch in 
for 2.12, but I agree that sooner is better than later and that doing 
this in 2.12 is worth the effort.

> 
> This doesn't implement any new functionality, so the only supported
> preallocation modes are 'off' and 'metadata' for now.
> 
> Signed-off-by: Kevin Wolf <kwolf@redhat.com>
> ---
>   qapi/block-core.json |  6 ++----
>   block/vdi.c          | 24 ++++++++++++++++++++++--
>   2 files changed, 24 insertions(+), 6 deletions(-)
> 

> +++ b/qapi/block-core.json
> @@ -3834,16 +3834,14 @@
>   #
>   # @file             Node to create the image format on
>   # @size             Size of the virtual disk in bytes
> -# @static           Whether to create a statically (true) or
> -#                   dynamically (false) allocated image
> -#                   (default: false, i.e. dynamic)
> +# @preallocation    Preallocation mode for the new image (default: off)

Do we want to document that 'full' is not supported yet?  Or is just 
relying on the error message good enough?

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

-- 
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org