[Libguestfs] [PATCH v2 3/4] libvirt backend: add detect-zeroes

[Richard W.M. Jones]

On Fri, Apr 24, 2015 at 02:51:50PM +0200, Maros Zatko wrote:
> @@ -1605,6 +1607,10 @@ construct_libvirt_xml_disk_driver_qemu (guestfs_h *g,
>      break;
>    }
>  
> +  if (data->qemu_version < 2001000) {
> +    detect_zeroes = false;
> +  }
> +
>    start_element ("driver") {
>      attribute ("name", "qemu");
>      attribute ("type", format);
> @@ -1613,6 +1619,8 @@ construct_libvirt_xml_disk_driver_qemu (guestfs_h *g,
>        attribute ("discard", "unmap");
>      if (copyonread)
>        attribute ("copy_on_read", "on");
> +    if (detect_zeroes)
> +      attribute ("detect_zeroes", "on");
>    } end_element ();
>  
>    return 0;

To make the code less fragile, reduce long-range dependencies.

Combine these two hunks into one:

  if (detect_zeroes && data->qemu_version < ...) {
    ...
  }

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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