[libvirt] [PATCH 06/22] vshExtractCPUDefXML: Accept domain capabilities XML

[Collin Walling]

On 05/16/2018 04:39 AM, Jiri Denemark wrote:
> The domain capabilities XML contains host CPU model tailored to a
> specific hypervisor and since it's enclosed in <mode name='host-model'>
> element rather then the required <cpu> it's impossible to directly use
> the host CPU model as an input to, e.g., cpu-compare command. To make
> this more convenient, vshExtractCPUDefXML now accepts full domain
> capabilities XML and automatically transforms the host CPU models into
> the form accepted by libvirt APIs.
> 
> Signed-off-by: Jiri Denemark <jdenemar at redhat.com>
> ---
>  tools/virsh-host.c | 26 ++++++++++++++++++++++----
>  tools/virsh.pod    |  8 +++++---
>  2 files changed, 27 insertions(+), 7 deletions(-)
> 
> diff --git a/tools/virsh-host.c b/tools/virsh-host.c
> index 51497db385..ea2c411c02 100644
> --- a/tools/virsh-host.c
> +++ b/tools/virsh-host.c
> @@ -1109,8 +1109,9 @@ cmdURI(vshControl *ctl, const vshCmd *cmd ATTRIBUTE_UNUSED)
>  
>  /* Extracts the CPU definition XML strings from a file which may contain either
>   *  - just the CPU definitions,
> - *  - domain XMLs, or
> - *  - capabilities XMLs.
> + *  - domain XMLs,
> + *  - capabilities XMLs, or
> + *  - domain capabilities XMLs.
>   *
>   * Returns NULL terminated string list.
>   */
> @@ -1138,20 +1139,37 @@ vshExtractCPUDefXMLs(vshControl *ctl,
>  
>      n = virXPathNodeSet("/container/cpu|"
>                          "/container/domain/cpu|"
> -                        "/container/capabilities/host/cpu",
> +                        "/container/capabilities/host/cpu|"
> +                        "/container/domainCapabilities/cpu/"
> +                            "mode[@name='host-model' and @supported='yes']",
>                          ctxt, &nodes);
>      if (n < 0)
>          goto error;
>  
>      if (n == 0) {
>          vshError(ctl, _("File '%s' does not contain any <cpu> element or "
> -                        "valid domain or capabilities XML"), xmlFile);
> +                        "valid domain XML, host capabilities XML, or "
> +                        "domain capabilities XML"), xmlFile);
>          goto error;
>      }
>  
>      cpus = vshCalloc(ctl, n + 1, sizeof(const char *));
>  
>      for (i = 0; i < n; i++) {
> +        /* If the user provided domain capabilities XML, we need to replace
> +         * <mode ...> element with <cpu>. */
> +        if (xmlStrEqual(nodes[i]->name, BAD_CAST "mode")) {
> +            xmlNodeSetName(nodes[i], (const xmlChar *)"cpu");
> +            while (nodes[i]->properties) {
> +                if (xmlRemoveProp(nodes[i]->properties) < 0) {
> +                    vshError(ctl,
> +                             _("Cannot extract CPU definition from domain "
> +                               "capabilities XML"));
> +                    goto error;
> +                }
> +            }
> +        }
> +
>          if (!(cpus[i] = virXMLNodeToString(xml, nodes[i]))) {
>              vshSaveLibvirtError();
>              goto error;
> diff --git a/tools/virsh.pod b/tools/virsh.pod
> index 5fc8201893..ea10e1ad43 100644
> --- a/tools/virsh.pod
> +++ b/tools/virsh.pod
> @@ -589,9 +589,11 @@ Compare CPU definition from XML <file> with host CPU. The XML <file> may
>  contain either host or guest CPU definition. The host CPU definition is the
>  <cpu> element and its contents as printed by B<capabilities> command. The
>  guest CPU definition is the <cpu> element and its contents from domain XML
> -definition. In addition to the <cpu> element itself, this command accepts
> -full domain or capabilities XML containing the <cpu> element. For more
> -information on guest CPU definition see:
> +definition or the CPU definition created from the host CPU model found in
> +domain capabilities XML (printed by B<domcapabilities> command). In
> +addition to the <cpu> element itself, this command accepts
> +full domain XML, capabilities XML, or domain capabilities XML containing
> +the CPU definition. For more information on guest CPU definition see:
>  L<https://libvirt.org/formatdomain.html#elementsCPU>. If I<--error> is
>  specified, the command will return an error when the given CPU is
>  incompatible with host CPU and a message providing more details about the
> 

Reviewed-by: Collin Walling <walling at linux.ibm.com>

-- 
Respectfully,
- Collin Walling