Re: [libvirt] [PATCH 1/8] conf: domcaps: Add 'backingStoreInput' domain capability

On Thu, Nov 21, 2019 at 18:19:55 +0000, Daniel Berrange wrote: > On Mon, Nov 18, 2019 at 06:02:01PM +0100, Peter Krempa wrote: > > Historically we've only supported the <backingStore> as an output-only > > element for domain disks. The documentation states that it may become > > supported on input. To allow management apps detectin once that happens > > s/detectin/to detect/ > > > add a domain capability which will be asserted if the hypervisor driver > > will be able to obey the <backingStore> as configured on input. > > > > Signed-off-by: Peter Krempa <pkrempa(a)redhat.com&gt; > > --- > > docs/formatdomaincaps.html.in | 7 +++++++ > > docs/schemas/domaincaps.rng | 9 +++++++++ > > src/conf/domain_capabilities.c | 1 + > > src/conf/domain_capabilities.h | 1 + > > tests/domaincapsdata/libxl-xenfv.xml | 1 + > > tests/domaincapsdata/libxl-xenpv.xml | 1 + > > tests/domaincapsdata/qemu_1.5.3-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_1.5.3-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_1.5.3.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_1.6.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_1.6.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_1.6.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_1.7.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_1.7.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_1.7.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.1.1-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.1.1-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.1.1.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.10.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.10.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.10.0-virt.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_2.10.0.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_2.10.0.ppc64.xml | 1 + > > tests/domaincapsdata/qemu_2.10.0.s390x.xml | 1 + > > tests/domaincapsdata/qemu_2.10.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.11.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.11.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.11.0.s390x.xml | 1 + > > tests/domaincapsdata/qemu_2.11.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.12.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.12.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.12.0-virt.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_2.12.0.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_2.12.0.ppc64.xml | 1 + > > tests/domaincapsdata/qemu_2.12.0.s390x.xml | 1 + > > tests/domaincapsdata/qemu_2.12.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.4.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.4.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.4.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.5.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.5.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.5.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.6.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.6.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.6.0-virt.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_2.6.0.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_2.6.0.ppc64.xml | 1 + > > tests/domaincapsdata/qemu_2.6.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.7.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.7.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.7.0.s390x.xml | 1 + > > tests/domaincapsdata/qemu_2.7.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.8.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.8.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.8.0.s390x.xml | 1 + > > tests/domaincapsdata/qemu_2.8.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.9.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.9.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_2.9.0.ppc64.xml | 1 + > > tests/domaincapsdata/qemu_2.9.0.s390x.xml | 1 + > > tests/domaincapsdata/qemu_2.9.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_3.0.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_3.0.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_3.0.0.ppc64.xml | 1 + > > tests/domaincapsdata/qemu_3.0.0.s390x.xml | 1 + > > tests/domaincapsdata/qemu_3.0.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_3.1.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_3.1.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_3.1.0.ppc64.xml | 1 + > > tests/domaincapsdata/qemu_3.1.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_4.0.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_4.0.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_4.0.0-virt.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_4.0.0.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_4.0.0.ppc64.xml | 1 + > > tests/domaincapsdata/qemu_4.0.0.s390x.xml | 1 + > > tests/domaincapsdata/qemu_4.0.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_4.1.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_4.1.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_4.1.0.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_4.2.0-q35.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_4.2.0-tcg.x86_64.xml | 1 + > > tests/domaincapsdata/qemu_4.2.0-virt.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_4.2.0.aarch64.xml | 1 + > > tests/domaincapsdata/qemu_4.2.0.ppc64.xml | 1 + > > tests/domaincapsdata/qemu_4.2.0.x86_64.xml | 1 + > > 86 files changed, 100 insertions(+) > > Reviewed-by: Daniel P. Berrangé <berrange(a)redhat.com&gt; > > > @@ -552,6 +553,12 @@ > > > > <p>Reports whether the genid feature can be used by the domain.</p> > > > > + <h4><a id="featureBackingStoreInput">backingStoreInput</a></h4> > > + > > + <p>Reports whether the hypervisor will obey the &lt;backingStore&gt; > > + elements configured for a &lt;disk&gt; on input during startup of the domain. > > + </p> > > "during startup of the domain" looks suspect to me. Do we not > obey backing store any time we process the XML, even for a inactive > guest, or when hotplugging into a running guest ? I wanted to somehow mention that while the XML may have the elements stored they are ignored (or not if the feature is available) when we process the definition. Yet the elements are still there so the 'on input' wording which we use in the domain definition also seemed a bit fishy though.