Add the ability to enable blob resources for the virtio video device.
This will accelerate the display path due to less or no copying of pixel
data.
Blob resource support can be enabled with e.g.:
<video>
<model type='virtio' blob='on'/>
</video>
Some additional background information about blob resources:
https://lists.freedesktop.org/archives/dri-devel/2020-August/275972.html
https://www.kraxel.org/blog/2021/05/virtio-gpu-qemu-graphics-update/
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2032406
Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
---
docs/formatdomain.rst | 6 ++++++
src/conf/domain_conf.c | 6 ++++++
src/conf/domain_conf.h | 1 +
src/conf/domain_validate.c | 13 ++++++++++---
src/conf/schemas/domaincommon.rng | 5 +++++
5 files changed, 28 insertions(+), 3 deletions(-)
diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index 993c65e50b..2161cc7e30 100644
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -6198,6 +6198,12 @@ A video device.
:since:`since 1.3.3` ) extends secondary bar and makes it addressable as
64bit memory.
+ :since:`Since 8.2.0`, devices with type "virtio" have an optional ``blob``
+ attribute that can be set to "on" or "off". Setting ``blob`` to "on" will
+ enable the use of blob resources in the device. This can accelerate the
+ display path by reducing or eliminating copying of pixel data between the
+ guest and host.
+
:since:`Since 5.9.0` , the ``model`` element may also have an optional
``resolution`` sub-element. The ``resolution`` element has attributes ``x``
and ``y`` to set the minimum resolution for the video device. This
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 60c27ddd34..ae86f455bd 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -14154,6 +14154,9 @@ virDomainVideoModelDefParseXML(virDomainVideoDef *def,
else if (rc == 0)
def->heads = 1;
+ if (virXMLPropTristateSwitch(node, "blob", VIR_XML_PROP_NONE, &def->blob) < 0)
+ return -1;
+
return 0;
}
@@ -26075,6 +26078,9 @@ virDomainVideoDefFormat(virBuffer *buf,
virBufferAsprintf(buf, " heads='%u'", def->heads);
if (def->primary)
virBufferAddLit(buf, " primary='yes'");
+ if (def->blob != VIR_TRISTATE_SWITCH_ABSENT)
+ virBufferAsprintf(buf, " blob='%s'",
+ virTristateSwitchTypeToString(def->blob));
if (def->accel || def->res) {
virBufferAddLit(buf, ">\n");
virBufferAdjustIndent(buf, 2);
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index acd0588e9b..afa6db2403 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -1763,6 +1763,7 @@ struct _virDomainVideoDef {
bool primary;
virDomainVideoAccelDef *accel;
virDomainVideoResolutionDef *res;
+ virTristateSwitch blob;
virDomainVideoDriverDef *driver;
virDomainDeviceInfo info;
virDomainVirtioOptions *virtio;
diff --git a/src/conf/domain_validate.c b/src/conf/domain_validate.c
index 18eb8d697d..da0ff06570 100644
--- a/src/conf/domain_validate.c
+++ b/src/conf/domain_validate.c
@@ -226,9 +226,16 @@ virDomainVideoDefValidate(const virDomainVideoDef *video,
}
}
- if (video->type != VIR_DOMAIN_VIDEO_TYPE_VIRTIO &&
- (virDomainCheckVirtioOptionsAreAbsent(video->virtio) < 0))
- return -1;
+ if (video->type != VIR_DOMAIN_VIDEO_TYPE_VIRTIO) {
+ if (virDomainCheckVirtioOptionsAreAbsent(video->virtio) < 0)
+ return -1;
+ if (video->blob != VIR_TRISTATE_SWITCH_ABSENT) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+ _("video type '%s' does not support blob resources"),
+ virDomainVideoTypeToString(video->type));
+ return -1;
+ }
+ }
return 0;
}
diff --git a/src/conf/schemas/domaincommon.rng b/src/conf/schemas/domaincommon.rng
index 2544864eb4..16b3fd9c53 100644
--- a/src/conf/schemas/domaincommon.rng
+++ b/src/conf/schemas/domaincommon.rng
@@ -4251,6 +4251,11 @@
<ref name="virYesNo"/>
</attribute>
</optional>
+ <optional>
+ <attribute name="blob">
+ <ref name="virOnOff"/>
+ </attribute>
+ </optional>
<optional>
<element name="acceleration">
<optional>
--
2.35.1On Wed, May 11, 2022 at 12:26 AM Jonathon Jongsma <jjongsma@redhat.com>
wrote:
> Add the ability to enable blob resources for the virtio video device.
> This will accelerate the display path due to less or no copying of pixel
> data.
>
> Blob resource support can be enabled with e.g.:
>
> <video>
> <model type='virtio' blob='on'/>
> </video>
>
> Some additional background information about blob resources:
> https://lists.freedesktop.org/archives/dri-devel/2020-August/275972.html
> https://www.kraxel.org/blog/2021/05/virtio-gpu-qemu-graphics-update/
>
> Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2032406
>
> Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
> ---
> docs/formatdomain.rst | 6 ++++++
> src/conf/domain_conf.c | 6 ++++++
> src/conf/domain_conf.h | 1 +
> src/conf/domain_validate.c | 13 ++++++++++---
> src/conf/schemas/domaincommon.rng | 5 +++++
> 5 files changed, 28 insertions(+), 3 deletions(-)
>
> diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
> index 993c65e50b..2161cc7e30 100644
> --- a/docs/formatdomain.rst
> +++ b/docs/formatdomain.rst
> @@ -6198,6 +6198,12 @@ A video device.
> :since:`since 1.3.3` ) extends secondary bar and makes it addressable
> as
> 64bit memory.
>
> + :since:`Since 8.2.0`, devices with type "virtio" have an optional
> ``blob``
>
Since 8.4.0 for libvirt.
And please mention the QEMU version 6.1.0
> + attribute that can be set to "on" or "off". Setting ``blob`` to "on"
> will
> + enable the use of blob resources in the device. This can accelerate the
> + display path by reducing or eliminating copying of pixel data between
> the
> + guest and host.
> +
> :since:`Since 5.9.0` , the ``model`` element may also have an optional
> ``resolution`` sub-element. The ``resolution`` element has attributes
> ``x``
> and ``y`` to set the minimum resolution for the video device. This
> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
> index 60c27ddd34..ae86f455bd 100644
> --- a/src/conf/domain_conf.c
> +++ b/src/conf/domain_conf.c
> @@ -14154,6 +14154,9 @@ virDomainVideoModelDefParseXML(virDomainVideoDef
> *def,
> else if (rc == 0)
> def->heads = 1;
>
> + if (virXMLPropTristateSwitch(node, "blob", VIR_XML_PROP_NONE,
> &def->blob) < 0)
> + return -1;
> +
> return 0;
> }
>
> @@ -26075,6 +26078,9 @@ virDomainVideoDefFormat(virBuffer *buf,
> virBufferAsprintf(buf, " heads='%u'", def->heads);
> if (def->primary)
> virBufferAddLit(buf, " primary='yes'");
> + if (def->blob != VIR_TRISTATE_SWITCH_ABSENT)
> + virBufferAsprintf(buf, " blob='%s'",
> + virTristateSwitchTypeToString(def->blob));
> if (def->accel || def->res) {
> virBufferAddLit(buf, ">\n");
> virBufferAdjustIndent(buf, 2);
> diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
> index acd0588e9b..afa6db2403 100644
> --- a/src/conf/domain_conf.h
> +++ b/src/conf/domain_conf.h
> @@ -1763,6 +1763,7 @@ struct _virDomainVideoDef {
> bool primary;
> virDomainVideoAccelDef *accel;
> virDomainVideoResolutionDef *res;
> + virTristateSwitch blob;
> virDomainVideoDriverDef *driver;
> virDomainDeviceInfo info;
> virDomainVirtioOptions *virtio;
> diff --git a/src/conf/domain_validate.c b/src/conf/domain_validate.c
> index 18eb8d697d..da0ff06570 100644
> --- a/src/conf/domain_validate.c
> +++ b/src/conf/domain_validate.c
> @@ -226,9 +226,16 @@ virDomainVideoDefValidate(const virDomainVideoDef
> *video,
> }
> }
>
> - if (video->type != VIR_DOMAIN_VIDEO_TYPE_VIRTIO &&
> - (virDomainCheckVirtioOptionsAreAbsent(video->virtio) < 0))
> - return -1;
> + if (video->type != VIR_DOMAIN_VIDEO_TYPE_VIRTIO) {
> + if (virDomainCheckVirtioOptionsAreAbsent(video->virtio) < 0)
> + return -1;
> + if (video->blob != VIR_TRISTATE_SWITCH_ABSENT) {
> + virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
> + _("video type '%s' does not support blob
> resources"),
> + virDomainVideoTypeToString(video->type));
> + return -1;
> + }
> + }
>
> return 0;
> }
> diff --git a/src/conf/schemas/domaincommon.rng
> b/src/conf/schemas/domaincommon.rng
> index 2544864eb4..16b3fd9c53 100644
> --- a/src/conf/schemas/domaincommon.rng
> +++ b/src/conf/schemas/domaincommon.rng
> @@ -4251,6 +4251,11 @@
> <ref name="virYesNo"/>
> </attribute>
> </optional>
> + <optional>
> + <attribute name="blob">
> + <ref name="virOnOff"/>
> + </attribute>
> + </optional>
> <optional>
> <element name="acceleration">
> <optional>
> --
> 2.35.1
>
>
On 5/11/22 9:56 AM, Han Han wrote:
>
>
> On Wed, May 11, 2022 at 12:26 AM Jonathon Jongsma <jjongsma@redhat.com
> <mailto:jjongsma@redhat.com>> wrote:
>
> Add the ability to enable blob resources for the virtio video device.
> This will accelerate the display path due to less or no copying of pixel
> data.
>
> Blob resource support can be enabled with e.g.:
>
> <video>
> <model type='virtio' blob='on'/>
> </video>
>
> Some additional background information about blob resources:
> https://lists.freedesktop.org/archives/dri-devel/2020-August/275972.html
> <https://lists.freedesktop.org/archives/dri-devel/2020-August/275972.html>
> https://www.kraxel.org/blog/2021/05/virtio-gpu-qemu-graphics-update/
> <https://www.kraxel.org/blog/2021/05/virtio-gpu-qemu-graphics-update/>
>
> Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2032406
> <https://bugzilla.redhat.com/show_bug.cgi?id=2032406>
>
> Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com
> <mailto:jjongsma@redhat.com>>
> ---
> docs/formatdomain.rst | 6 ++++++
> src/conf/domain_conf.c | 6 ++++++
> src/conf/domain_conf.h | 1 +
> src/conf/domain_validate.c | 13 ++++++++++---
> src/conf/schemas/domaincommon.rng | 5 +++++
> 5 files changed, 28 insertions(+), 3 deletions(-)
>
> diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
> index 993c65e50b..2161cc7e30 100644
> --- a/docs/formatdomain.rst
> +++ b/docs/formatdomain.rst
> @@ -6198,6 +6198,12 @@ A video device.
> :since:`since 1.3.3` ) extends secondary bar and makes it
> addressable as
> 64bit memory.
>
> + :since:`Since 8.2.0`, devices with type "virtio" have an
> optional ``blob``
>
> Since 8.4.0 for libvirt.
Oops. Didn't catch that in the rebase.
> And please mention the QEMU version 6.1.0
There are a lot of libvirt features that require minimum versions of
qemu, but it doesn't look like we generally specify these qemu version
requirements in the libvirt documentation. Not sure if I should add it
here...
>
> + attribute that can be set to "on" or "off". Setting ``blob`` to
> "on" will
> + enable the use of blob resources in the device. This can
> accelerate the
> + display path by reducing or eliminating copying of pixel data
> between the
> + guest and host.
> +
> :since:`Since 5.9.0` , the ``model`` element may also have an
> optional
> ``resolution`` sub-element. The ``resolution`` element has
> attributes ``x``
> and ``y`` to set the minimum resolution for the video device. This
> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
> index 60c27ddd34..ae86f455bd 100644
> --- a/src/conf/domain_conf.c
> +++ b/src/conf/domain_conf.c
> @@ -14154,6 +14154,9 @@
> virDomainVideoModelDefParseXML(virDomainVideoDef *def,
> else if (rc == 0)
> def->heads = 1;
>
> + if (virXMLPropTristateSwitch(node, "blob", VIR_XML_PROP_NONE,
> &def->blob) < 0)
> + return -1;
> +
> return 0;
> }
>
> @@ -26075,6 +26078,9 @@ virDomainVideoDefFormat(virBuffer *buf,
> virBufferAsprintf(buf, " heads='%u'", def->heads);
> if (def->primary)
> virBufferAddLit(buf, " primary='yes'");
> + if (def->blob != VIR_TRISTATE_SWITCH_ABSENT)
> + virBufferAsprintf(buf, " blob='%s'",
> + virTristateSwitchTypeToString(def->blob));
> if (def->accel || def->res) {
> virBufferAddLit(buf, ">\n");
> virBufferAdjustIndent(buf, 2);
> diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
> index acd0588e9b..afa6db2403 100644
> --- a/src/conf/domain_conf.h
> +++ b/src/conf/domain_conf.h
> @@ -1763,6 +1763,7 @@ struct _virDomainVideoDef {
> bool primary;
> virDomainVideoAccelDef *accel;
> virDomainVideoResolutionDef *res;
> + virTristateSwitch blob;
> virDomainVideoDriverDef *driver;
> virDomainDeviceInfo info;
> virDomainVirtioOptions *virtio;
> diff --git a/src/conf/domain_validate.c b/src/conf/domain_validate.c
> index 18eb8d697d..da0ff06570 100644
> --- a/src/conf/domain_validate.c
> +++ b/src/conf/domain_validate.c
> @@ -226,9 +226,16 @@ virDomainVideoDefValidate(const
> virDomainVideoDef *video,
> }
> }
>
> - if (video->type != VIR_DOMAIN_VIDEO_TYPE_VIRTIO &&
> - (virDomainCheckVirtioOptionsAreAbsent(video->virtio) < 0))
> - return -1;
> + if (video->type != VIR_DOMAIN_VIDEO_TYPE_VIRTIO) {
> + if (virDomainCheckVirtioOptionsAreAbsent(video->virtio) < 0)
> + return -1;
> + if (video->blob != VIR_TRISTATE_SWITCH_ABSENT) {
> + virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
> + _("video type '%s' does not support blob
> resources"),
> + virDomainVideoTypeToString(video->type));
> + return -1;
> + }
> + }
>
> return 0;
> }
> diff --git a/src/conf/schemas/domaincommon.rng
> b/src/conf/schemas/domaincommon.rng
> index 2544864eb4..16b3fd9c53 100644
> --- a/src/conf/schemas/domaincommon.rng
> +++ b/src/conf/schemas/domaincommon.rng
> @@ -4251,6 +4251,11 @@
> <ref name="virYesNo"/>
> </attribute>
> </optional>
> + <optional>
> + <attribute name="blob">
> + <ref name="virOnOff"/>
> + </attribute>
> + </optional>
> <optional>
> <element name="acceleration">
> <optional>
> --
> 2.35.1
>
On Wed, May 11, 2022 at 13:28:02 -0500, Jonathon Jongsma wrote: > On 5/11/22 9:56 AM, Han Han wrote: > > > > > > On Wed, May 11, 2022 at 12:26 AM Jonathon Jongsma <jjongsma@redhat.com > > <mailto:jjongsma@redhat.com>> wrote: [...] > > Since 8.4.0 for libvirt. > > Oops. Didn't catch that in the rebase. > > > And please mention the QEMU version 6.1.0 > > There are a lot of libvirt features that require minimum versions of qemu, > but it doesn't look like we generally specify these qemu version > requirements in the libvirt documentation. Not sure if I should add it > here... We mention the required qemu version in many cases, so it definitely will not be an outlier. Usually it's when either it's important, a recent addition or somebody cares about adding it.
On Thu, May 12, 2022 at 2:28 AM Jonathon Jongsma <jjongsma@redhat.com>
wrote:
> On 5/11/22 9:56 AM, Han Han wrote:
> >
> >
> > On Wed, May 11, 2022 at 12:26 AM Jonathon Jongsma <jjongsma@redhat.com
> > <mailto:jjongsma@redhat.com>> wrote:
> >
> > Add the ability to enable blob resources for the virtio video device.
> > This will accelerate the display path due to less or no copying of
> pixel
> > data.
> >
> > Blob resource support can be enabled with e.g.:
> >
> > <video>
> > <model type='virtio' blob='on'/>
> > </video>
> >
> > Some additional background information about blob resources:
> >
> https://lists.freedesktop.org/archives/dri-devel/2020-August/275972.html
> > <
> https://lists.freedesktop.org/archives/dri-devel/2020-August/275972.html>
> > https://www.kraxel.org/blog/2021/05/virtio-gpu-qemu-graphics-update/
> > <
> https://www.kraxel.org/blog/2021/05/virtio-gpu-qemu-graphics-update/>
> >
> > Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2032406
> > <https://bugzilla.redhat.com/show_bug.cgi?id=2032406>
> >
> > Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com
> > <mailto:jjongsma@redhat.com>>
> > ---
> > docs/formatdomain.rst | 6 ++++++
> > src/conf/domain_conf.c | 6 ++++++
> > src/conf/domain_conf.h | 1 +
> > src/conf/domain_validate.c | 13 ++++++++++---
> > src/conf/schemas/domaincommon.rng | 5 +++++
> > 5 files changed, 28 insertions(+), 3 deletions(-)
> >
> > diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
> > index 993c65e50b..2161cc7e30 100644
> > --- a/docs/formatdomain.rst
> > +++ b/docs/formatdomain.rst
> > @@ -6198,6 +6198,12 @@ A video device.
> > :since:`since 1.3.3` ) extends secondary bar and makes it
> > addressable as
> > 64bit memory.
> >
> > + :since:`Since 8.2.0`, devices with type "virtio" have an
> > optional ``blob``
> >
> > Since 8.4.0 for libvirt.
>
> Oops. Didn't catch that in the rebase.
>
> > And please mention the QEMU version 6.1.0
>
> There are a lot of libvirt features that require minimum versions of
> qemu, but it doesn't look like we generally specify these qemu version
> requirements in the libvirt documentation. Not sure if I should add it
> here...
>
Generally, the minimal required QEMU version is 3.1.0(
https://libvirt.org/drvqemu.html):
"The libvirt KVM/QEMU driver can manage any QEMU emulator from version
3.1.0 or later"
That's to say, a user can use 3.1.0<=QEMU<6.2.0 with current libvirt.
So it's better to mention the required QEMU version for 'blob' to help
users resolved the unsupported error.
>
> >
> > + attribute that can be set to "on" or "off". Setting ``blob`` to
> > "on" will
> > + enable the use of blob resources in the device. This can
> > accelerate the
> > + display path by reducing or eliminating copying of pixel data
> > between the
> > + guest and host.
> > +
> > :since:`Since 5.9.0` , the ``model`` element may also have an
> > optional
> > ``resolution`` sub-element. The ``resolution`` element has
> > attributes ``x``
> > and ``y`` to set the minimum resolution for the video device.
> This
> > diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
> > index 60c27ddd34..ae86f455bd 100644
> > --- a/src/conf/domain_conf.c
> > +++ b/src/conf/domain_conf.c
> > @@ -14154,6 +14154,9 @@
> > virDomainVideoModelDefParseXML(virDomainVideoDef *def,
> > else if (rc == 0)
> > def->heads = 1;
> >
> > + if (virXMLPropTristateSwitch(node, "blob", VIR_XML_PROP_NONE,
> > &def->blob) < 0)
> > + return -1;
> > +
> > return 0;
> > }
> >
> > @@ -26075,6 +26078,9 @@ virDomainVideoDefFormat(virBuffer *buf,
> > virBufferAsprintf(buf, " heads='%u'", def->heads);
> > if (def->primary)
> > virBufferAddLit(buf, " primary='yes'");
> > + if (def->blob != VIR_TRISTATE_SWITCH_ABSENT)
> > + virBufferAsprintf(buf, " blob='%s'",
> > + virTristateSwitchTypeToString(def->blob));
> > if (def->accel || def->res) {
> > virBufferAddLit(buf, ">\n");
> > virBufferAdjustIndent(buf, 2);
> > diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
> > index acd0588e9b..afa6db2403 100644
> > --- a/src/conf/domain_conf.h
> > +++ b/src/conf/domain_conf.h
> > @@ -1763,6 +1763,7 @@ struct _virDomainVideoDef {
> > bool primary;
> > virDomainVideoAccelDef *accel;
> > virDomainVideoResolutionDef *res;
> > + virTristateSwitch blob;
> > virDomainVideoDriverDef *driver;
> > virDomainDeviceInfo info;
> > virDomainVirtioOptions *virtio;
> > diff --git a/src/conf/domain_validate.c b/src/conf/domain_validate.c
> > index 18eb8d697d..da0ff06570 100644
> > --- a/src/conf/domain_validate.c
> > +++ b/src/conf/domain_validate.c
> > @@ -226,9 +226,16 @@ virDomainVideoDefValidate(const
> > virDomainVideoDef *video,
> > }
> > }
> >
> > - if (video->type != VIR_DOMAIN_VIDEO_TYPE_VIRTIO &&
> > - (virDomainCheckVirtioOptionsAreAbsent(video->virtio) < 0))
> > - return -1;
> > + if (video->type != VIR_DOMAIN_VIDEO_TYPE_VIRTIO) {
> > + if (virDomainCheckVirtioOptionsAreAbsent(video->virtio) < 0)
> > + return -1;
> > + if (video->blob != VIR_TRISTATE_SWITCH_ABSENT) {
> > + virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
> > + _("video type '%s' does not support blob
> > resources"),
> > + virDomainVideoTypeToString(video->type));
> > + return -1;
> > + }
> > + }
> >
> > return 0;
> > }
> > diff --git a/src/conf/schemas/domaincommon.rng
> > b/src/conf/schemas/domaincommon.rng
> > index 2544864eb4..16b3fd9c53 100644
> > --- a/src/conf/schemas/domaincommon.rng
> > +++ b/src/conf/schemas/domaincommon.rng
> > @@ -4251,6 +4251,11 @@
> > <ref name="virYesNo"/>
> > </attribute>
> > </optional>
> > + <optional>
> > + <attribute name="blob">
> > + <ref name="virOnOff"/>
> > + </attribute>
> > + </optional>
> > <optional>
> > <element name="acceleration">
> > <optional>
> > --
> > 2.35.1
> >
>
>
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