On 11.05.2016 00:42, Cole Robinson wrote:
On 05/10/2016 08:46 AM, Andrea Bolognani wrote:
When the <gic/> element in not present in the domain XML, use the domain capabilities to figure out what GIC version is usable and choose that one automatically.
This allows guests to be created on hardware that only supports GIC v3 without having to update virt-manager and similar tools.
Keep using the default GIC version if the <gic/> element has been added to the domain XML but no version has been specified, as not to break existing guests. --- src/conf/domain_capabilities.c | 25 ++++++++++++++++ src/conf/domain_capabilities.h | 8 +++++ src/libvirt_private.syms | 1 + src/qemu/qemu_domain.c | 66 ++++++++++++++++++++++++++++++++++-------- 4 files changed, 88 insertions(+), 12 deletions(-)
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 93f0a01..d34450f 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -1921,26 +1921,67 @@ qemuDomainDefAddDefaultDevices(virDomainDefPtr def, * Make sure that features that should be enabled by default are actually * enabled and configure default values related to those features. */ -static void -qemuDomainDefEnableDefaultFeatures(virDomainDefPtr def) +static int +qemuDomainDefEnableDefaultFeatures(virDomainDefPtr def, + virQEMUCapsPtr qemuCaps) { - switch (def->os.arch) { - case VIR_ARCH_ARMV7L: - case VIR_ARCH_AARCH64: - if (qemuDomainMachineIsVirt(def)) { - /* GIC is always available to ARM virt machines */ - def->features[VIR_DOMAIN_FEATURE_GIC] = VIR_TRISTATE_SWITCH_ON; + virDomainCapsPtr caps = NULL; + virDomainCapsFeatureGICPtr gic = NULL; + int ret = -1; + + /* The virt machine type always uses GIC: if the relevant element + * was not included in the domain XML, we need to choose a suitable + * GIC version ourselves */ + if ((def->os.arch == VIR_ARCH_ARMV7L || + def->os.arch == VIR_ARCH_AARCH64) && + qemuDomainMachineIsVirt(def) && + def->features[VIR_DOMAIN_FEATURE_GIC] == VIR_TRISTATE_SWITCH_ABSENT) { + + if (!(caps = virDomainCapsNew(def->emulator, + def->os.machine, + def->os.arch, + def->virtType))) + goto cleanup; +
Call this domCaps ? 'caps' name is usually used for virCapabilities
+ if (virQEMUCapsFillDomainCaps(caps, qemuCaps, NULL, 0) < 0) + goto cleanup; + + gic = &(caps->gic); + + /* Pick the best GIC version from those available */ + if (gic->supported) { + virGICVersion version; + + VIR_DEBUG("Looking for usable GIC version in domain capabilities"); + for (version = VIR_GIC_VERSION_LAST - 1; + version > VIR_GIC_VERSION_NONE; + version--) { + if (VIR_DOMAIN_CAPS_ENUM_IS_SET(gic->version, version)) { + + VIR_DEBUG("Using GIC version %s", + virGICVersionTypeToString(version)); + def->gic_version = version; + break; + } + } }
Hmm that's a bit of a new pattern... it seems the only thing you really need from domcaps is the bit of logic we encode via virQEMUCapsFillDomainFeatureGICCaps. Maybe break that logic out into a public function and call it here, rather than spinning up domcaps for a small bit of info? Or is there more to it?
Agreed. This looks like too heavy hammer for nail this small. Michal