From: Nathan Chen <nathanc@nvidia.com> Implement a new iommufd attribute under hostdevs' PCI subsystem driver that can be used to specify associated iommufd object when launching a qemu VM. Signed-off-by: Ján Tomko <jtomko@redhat.com> Signed-off-by: Nathan Chen <nathanc@nvidia.com> --- docs/formatdomain.rst | 6 +++++ src/conf/device_conf.c | 11 ++++++++ src/conf/device_conf.h | 1 + src/conf/schemas/basictypes.rng | 5 ++++ src/qemu/qemu_command.c | 46 +++++++++++++++++++++++++++++++++ 5 files changed, 69 insertions(+) diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst index 04ef319a73..f85a113344 100644 --- a/docs/formatdomain.rst +++ b/docs/formatdomain.rst @@ -4920,6 +4920,12 @@ or: found is "problematic" in some way, the generic vfio-pci driver similarly be forced. + :since:`Since 12.1.0 (QEMU and KVM only)`, the ``iommufd`` element + can be used to enable IOMMUFD backend for VFIO device. This + provides an interface to propagate DMA mappings to kernel for + assigned devices. Libvirt will open the /dev/iommu and VFIO device + cdev and pass associated file descriptors to QEMU. + (Note: :since:`Since 1.0.5`, the ``name`` attribute has been described to be used to select the type of PCI device assignment ("vfio", "kvm", or "xen"), but those values have been mostly diff --git a/src/conf/device_conf.c b/src/conf/device_conf.c index c278b81652..d68232a4f4 100644 --- a/src/conf/device_conf.c +++ b/src/conf/device_conf.c @@ -67,6 +67,11 @@ virDeviceHostdevPCIDriverInfoParseXML(xmlNodePtr node, return -1; } + if (virXMLPropTristateBool(node, "iommufd", + VIR_XML_PROP_NONE, + &driver->iommufd) < 0) + return -1; + driver->model = virXMLPropString(node, "model"); return 0; } @@ -93,6 +98,12 @@ virDeviceHostdevPCIDriverInfoFormat(virBuffer *buf, virBufferEscapeString(&driverAttrBuf, " model='%s'", driver->model); + if (driver->iommufd == VIR_TRISTATE_BOOL_YES) { + virBufferAddLit(&driverAttrBuf, " iommufd='yes'"); + } else if (driver->iommufd == VIR_TRISTATE_BOOL_NO) { + virBufferAddLit(&driverAttrBuf, " iommufd='no'"); + } + virXMLFormatElement(buf, "driver", &driverAttrBuf, NULL); return 0; } diff --git a/src/conf/device_conf.h b/src/conf/device_conf.h index e570f51824..116b959143 100644 --- a/src/conf/device_conf.h +++ b/src/conf/device_conf.h @@ -47,6 +47,7 @@ VIR_ENUM_DECL(virDeviceHostdevPCIDriverName); struct _virDeviceHostdevPCIDriverInfo { virDeviceHostdevPCIDriverName name; char *model; + virTristateBool iommufd; }; typedef enum { diff --git a/src/conf/schemas/basictypes.rng b/src/conf/schemas/basictypes.rng index 5689170fad..381e0ac24f 100644 --- a/src/conf/schemas/basictypes.rng +++ b/src/conf/schemas/basictypes.rng @@ -673,6 +673,11 @@ <ref name="genericName"/> </attribute> </optional> + <optional> + <attribute name="iommufd"> + <ref name="virYesNo"/> + </attribute> + </optional> <empty/> </element> </define> diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index e81efdfde7..fb09c678f3 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -4761,6 +4761,7 @@ qemuBuildPCIHostdevDevProps(const virDomainDef *def, g_autofree char *host = virPCIDeviceAddressAsString(&pcisrc->addr); const char *failover_pair_id = NULL; const char *driver = NULL; + const char *iommufdId = NULL; /* 'ramfb' property must be omitted unless it's to be enabled */ bool ramfb = pcisrc->ramfb == VIR_TRISTATE_SWITCH_ON; @@ -4794,6 +4795,9 @@ qemuBuildPCIHostdevDevProps(const virDomainDef *def, teaming->persistent) failover_pair_id = teaming->persistent; + if (pcisrc->driver.iommufd == VIR_TRISTATE_BOOL_YES) + iommufdId = "iommufd0"; + if (virJSONValueObjectAdd(&props, "s:driver", driver, "s:host", host, @@ -4802,6 +4806,7 @@ qemuBuildPCIHostdevDevProps(const virDomainDef *def, "S:failover_pair_id", failover_pair_id, "S:display", qemuOnOffAuto(pcisrc->display), "B:ramfb", ramfb, + "S:iommufd", iommufdId, NULL) < 0) return NULL; @@ -5321,6 +5326,44 @@ qemuBuildHostdevCommandLine(virCommand *cmd, } +static int +qemuBuildIOMMUFDCommandLine(virCommand *cmd, + const virDomainDef *def) +{ + size_t i; + + for (i = 0; i < def->nhostdevs; i++) { + virDomainHostdevDef *hostdev = def->hostdevs[i]; + virDomainHostdevSubsys *subsys = &hostdev->source.subsys; + g_autoptr(virJSONValue) props = NULL; + + if (hostdev->mode != VIR_DOMAIN_HOSTDEV_MODE_SUBSYS) + continue; + + if (subsys->type != VIR_DOMAIN_HOSTDEV_SUBSYS_TYPE_PCI) + continue; + + if (hostdev->info->type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_UNASSIGNED) + continue; + + if (subsys->u.pci.driver.iommufd != VIR_TRISTATE_BOOL_YES) + continue; + + if (qemuMonitorCreateObjectProps(&props, "iommufd", + "iommufd0", + NULL) < 0) + return -1; + + if (qemuBuildObjectCommandlineFromJSON(cmd, props) < 0) + return -1; + + break; + } + + return 0; +} + + static int qemuBuildMonitorCommandLine(virCommand *cmd, qemuDomainObjPrivate *priv) @@ -10933,6 +10976,9 @@ qemuBuildCommandLine(virDomainObj *vm, if (qemuBuildRedirdevCommandLine(cmd, def, qemuCaps) < 0) return NULL; + if (qemuBuildIOMMUFDCommandLine(cmd, def) < 0) + return NULL; + if (qemuBuildHostdevCommandLine(cmd, def, qemuCaps) < 0) return NULL; -- 2.43.0