[libvirt] [PATCH v2 1/3] conf : Add loadparm boot option for a boot device

[Christian Borntraeger]

On 05/19/2017 06:56 PM, Farhan Ali wrote:
> Update the per device boot schema to add an optional loadparm parameter.
> Extend the virDomainDeviceInfo to support loadparm option.
> Modify the appropriate functions to parse loadparm from boot device xml.
> 
> Signed-off-by: Farhan Ali <alifm at linux.vnet.ibm.com>
> Reviewed-by: Bjoern Walk <bwalk at linux.vnet.ibm.com>
> Reviewed-by: Boris Fiuczynski <fiuczy at linux.vnet.ibm.com>
> Reviewed-by: Marc Hartmayer <mhartmay at linux.vnet.ibm.com>
> ---
>  docs/formatdomain.html.in     |  8 +++--
>  docs/news.xml                 |  9 ++++++
>  docs/schemas/domaincommon.rng |  7 +++++
>  src/conf/device_conf.h        |  1 +
>  src/conf/domain_conf.c        | 69 +++++++++++++++++++++++++++++++++++++++++--
>  5 files changed, 90 insertions(+), 4 deletions(-)
> 
> diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
> index 3135db4..016febe 100644
> --- a/docs/formatdomain.html.in
> +++ b/docs/formatdomain.html.in
> @@ -3022,8 +3022,12 @@
>        <dt><code>boot</code></dt>
>        <dd>Specifies that the disk is bootable. The <code>order</code>
>          attribute determines the order in which devices will be tried during
> -        boot sequence. The per-device <code>boot</code> elements cannot be
> -        used together with general boot elements in
> +        boot sequence. On S390 architecture only the first boot device is used.
> +        The optional <code>loadparm</code> attribute can be used to select a
> +        boot entry for S390 architecture.
> +        <span class="since">Since 3.4.0</span>
> +        The per-device <code>boot</code> elements cannot be used together
> +        with general boot elements in
>          <a href="#elementsOSBIOS">BIOS bootloader</a> section.
>          <span class="since">Since 0.8.8</span>
>        </dd>
> diff --git a/docs/news.xml b/docs/news.xml
> index 52915ee..bc6b070 100644
> --- a/docs/news.xml
> +++ b/docs/news.xml
> @@ -37,6 +37,15 @@
>      <section title="New features">
>        <change>
>          <summary>
> +          qemu: Add support for loadparm for a boot device
> +        </summary>
> +        <description>
> +          Add an optional boot parameter 'loadparm' for a boot device.
> +          On S390 architecture the loadparm is used to select a boot entry.

I would change that description and refer more to the architectural meaning
(8 byte parameter that can be queried by the guest via sclp and diag 308).
The linux use case of the selecting a boot entry withing that disk can be mentioned
but it certainly is not the only use case.