[PATCH v2 2/3] conf: Add page_per_vq for driver element
Signed-off-by: Han Han <hhan(a)redhat.com>
---
docs/formatdomain.rst | 9 +++++++++
docs/schemas/domaincommon.rng | 5 +++++
src/conf/domain_conf.c | 16 ++++++++++++++++
src/conf/domain_conf.h | 1 +
src/conf/domain_validate.c | 6 ++++++
5 files changed, 37 insertions(+)
diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index a02802a954..289e7bf5f1 100644
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -3548,6 +3548,15 @@ virtqueues are actually used depends on the feature negotiation
between QEMU,
vhost backends and guest drivers. Possible values are ``on`` or ``off``.
:since:`Since 6.3.0 (QEMU and KVM only)`
+This optional attribute ``page_per_vq`` controls the layout of the notification
+capabilities exposed to the guest. When enabled, each virtio queue will have a
+dedicated page on the device BAR exposed to the guest. It is recommended to be
+used when vDPA is enabled on the hypervisor, as it enables mapping the
+notification area to the physical device, which is only supported in page
+granularity. The default is determined by QEMU. :since:`Since 7.8.0`
+Note: In general you should leave this option alone, unless you are very certain
+you know what you are doing.
+
:anchor:`<a id="elementsVirtioTransitional"/>`
Virtio transitional devices
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index ec5bd91740..f71e375a33 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -6810,6 +6810,11 @@
<ref name="virOnOff"/>
</attribute>
</optional>
+ <optional>
+ <attribute name="page_per_vq">
+ <ref name="virOnOff"/>
+ </attribute>
+ </optional>
</define>
<define name="usbmaster">
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index b8370f6950..04bdd110b6 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -1630,6 +1630,10 @@ virDomainVirtioOptionsParseXML(xmlNodePtr driver,
&(*virtio)->packed) < 0)
return -1;
+ if (virXMLPropTristateSwitch(driver, "page_per_vq", VIR_XML_PROP_NONE,
+ &(*virtio)->page_per_vq) < 0)
+ return -1;
+
return 0;
}
@@ -6314,6 +6318,10 @@ virDomainVirtioOptionsFormat(virBuffer *buf,
virBufferAsprintf(buf, " packed='%s'",
virTristateSwitchTypeToString(virtio->packed));
}
+ if (virtio->page_per_vq != VIR_TRISTATE_SWITCH_ABSENT) {
+ virBufferAsprintf(buf, " page_per_vq='%s'",
+ virTristateSwitchTypeToString(virtio->page_per_vq));
+ }
}
@@ -20784,6 +20792,14 @@ virDomainVirtioOptionsCheckABIStability(virDomainVirtioOptions
*src,
virTristateSwitchTypeToString(src->packed));
return false;
}
+ if (src->page_per_vq != dst->page_per_vq) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+ _("Target device page_per_vq option '%s' does not
"
+ "match source '%s'"),
+ virTristateSwitchTypeToString(dst->page_per_vq),
+ virTristateSwitchTypeToString(src->page_per_vq));
+ return false;
+ }
return true;
}
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index c23c233184..d6bc3dd0d2 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -2733,6 +2733,7 @@ struct _virDomainVirtioOptions {
virTristateSwitch iommu;
virTristateSwitch ats;
virTristateSwitch packed;
+ virTristateSwitch page_per_vq;
};
diff --git a/src/conf/domain_validate.c b/src/conf/domain_validate.c
index f023d22f23..80401cf8c7 100644
--- a/src/conf/domain_validate.c
+++ b/src/conf/domain_validate.c
@@ -135,6 +135,12 @@ virDomainCheckVirtioOptionsAreAbsent(virDomainVirtioOptions *virtio)
"for virtio devices"));
return -1;
}
+
+ if (virtio->page_per_vq != VIR_TRISTATE_SWITCH_ABSENT) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+ _("page_per_vq option is only supported for virtio
devices"));
+ return -1;
+ }
return 0;
}
--
2.31.1