[PATCH v2 4/8] domain_conf.c: XML parsing for VIR_DOMAIN_TPM_MODEL_SPAPR_PROXY

[Stefan Berger]

On 5/13/20 10:10 AM, Daniel Henrique Barboza wrote:
> Aside from trivial XML parsing/format changes, this patch adds
> additional rules for TPM device support to better accomodate
> all the available scenarios with the new TPM Proxy.
>
> The changes make no impact to existing domains. This means that
> the scenario of a domain with a single TPM device is still
> supported in the same way.  The restriction of multiple TPM devices
> got alleviated to allow a TPM Proxy device to be added together
> with a TPM device in the same domain. All other combinations
> are still forbidden.
>
> To summarize, after this patch, the following combinations in the same
> domain are valid:
>
> - a single TPM device
> - a single TPM Proxy device
> - a single TPM + single TPM Proxy devices
>
> These combinations in the same domain are NOT allowed:
>
> - 2 or more TPM devices
> - 2 or more TPM Proxy devices
>
> Signed-off-by: Daniel Henrique Barboza <danielhb413 at gmail.com>
> ---
>   src/conf/domain_conf.c | 47 ++++++++++++++++++++++++++++++++++++++----
>   1 file changed, 43 insertions(+), 4 deletions(-)
>
> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
> index 01a32f62d1..33b7d69318 100644
> --- a/src/conf/domain_conf.c
> +++ b/src/conf/domain_conf.c
> @@ -13730,6 +13730,14 @@ virDomainTPMDefParseXML(virDomainXMLOptionPtr xmlopt,
>           goto error;
>       }
>   
> +    /* TPM Proxy devices have 'passthrough' backend */
> +    if (def->model == VIR_DOMAIN_TPM_MODEL_SPAPR_PROXY &&
> +        def->type != VIR_DOMAIN_TPM_TYPE_PASSTHROUGH) {
> +        virReportError(VIR_ERR_XML_ERROR, "%s",
> +                       _("'Passthrough' backend is required for TPM Proxy devices"));
> +        goto error;
> +    }
> +
>       if (virDomainDeviceInfoParseXML(xmlopt, node, &def->info, flags) < 0)
>           goto error;
>   
> @@ -21972,15 +21980,41 @@ virDomainDefParseXML(xmlDocPtr xml,
>       if ((n = virXPathNodeSet("./devices/tpm", ctxt, &nodes)) < 0)
>           goto error;
>   
> -    if (n > 1) {
> +    if (n > 2) {
>           virReportError(VIR_ERR_XML_ERROR, "%s",
> -                       _("only a single TPM device is supported"));
> +                       _("a maximum of two TPM devices is supported, one of "
> +                         "them being a TPM Proxy device"));
>           goto error;
>       }
>   
>       if (n > 0) {
> -        if (!(def->tpm = virDomainTPMDefParseXML(xmlopt, nodes[0], ctxt, flags)))
> -            goto error;
> +        for (i = 0; i < n; i++) {
> +            virDomainTPMDefPtr dev = virDomainTPMDefParseXML(xmlopt, nodes[i], ctxt, flags);
> +
> +            if (!dev)
> +                goto error;
> +
> +            /* TPM Proxy devices must be held in def->tpmproxy. Error
> +             * out if there's a TPM Proxy declared already */
> +            if (dev->model == VIR_DOMAIN_TPM_MODEL_SPAPR_PROXY) {
> +                if (def->tpmproxy) {
> +                    virReportError(VIR_ERR_XML_ERROR, "%s",
> +                                   _("only a single TPM Proxy device is supported"));
> +                    VIR_FREE(dev);
> +                    goto error;
> +                }
> +                def->tpmproxy = g_steal_pointer(&dev);


Is g_steal_pointer necessary ?


> +            } else {
> +                /* all other TPM devices goes to def->tpm */
> +                if (def->tpm) {
> +                    virReportError(VIR_ERR_XML_ERROR, "%s",
> +                                   _("only a single TPM non-proxy device is supported"));
> +                    VIR_FREE(dev);
> +                    goto error;
> +                }
> +                def->tpm = g_steal_pointer(&dev);
> +            }
> +        }
>       }
>       VIR_FREE(nodes);
>   
> @@ -29807,6 +29841,11 @@ virDomainDefFormatInternalSetRootName(virDomainDefPtr def,
>               goto error;
>       }
>   
> +    if (def->tpmproxy) {
> +        if (virDomainTPMDefFormat(buf, def->tpmproxy, flags) < 0)
> +            goto error;
> +    }
> +
>       for (n = 0; n < def->ngraphics; n++) {
>           if (virDomainGraphicsDefFormat(buf, def->graphics[n], flags) < 0)
>               goto error;