Re: [libvirt] [PATCHv3 11/12] qemu: Implement memory device hotplug

Add code to hot-add memory devices to running qemu instances. --- Notes: Version 3: - added comment to clarify that @mem is always consumed by qemuDomainAttachMemory Version 2: - no change Version 2: - no change src/qemu/qemu_command.c | 4 +-- src/qemu/qemu_command.h | 15 ++++++++ src/qemu/qemu_driver.c | 5 ++- src/qemu/qemu_hotplug.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++ src/qemu/qemu_hotplug.h | 3 ++ 5 files changed, 119 insertions(+), 3 deletions(-) diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 2d85567..1f72437 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -4599,7 +4599,7 @@ qemuBuildControllerDevStr(virDomainDefPtr domainDef, * other configuration was used (to detect legacy configurations). Returns * -1 in case of an error. */ -static int +int qemuBuildMemoryBackendStr(unsigned long long size, unsigned long long pagesize, int guestNode, @@ -4872,7 +4872,7 @@ qemuBuildMemoryDimmBackendStr(virDomainMemoryDefPtr mem, } -static char * +char * qemuBuildMemoryDeviceStr(virDomainMemoryDefPtr mem, virQEMUCapsPtr qemuCaps) { diff --git a/src/qemu/qemu_command.h b/src/qemu/qemu_command.h index ee81f92..a29db41 100644 --- a/src/qemu/qemu_command.h +++ b/src/qemu/qemu_command.h @@ -162,6 +162,21 @@ char *qemuBuildSoundDevStr(virDomainDefPtr domainDef, virDomainSoundDefPtr sound, virQEMUCapsPtr qemuCaps); +int qemuBuildMemoryBackendStr(unsigned long long size, + unsigned long long pagesize, + int guestNode, + virBitmapPtr userNodeset, + virBitmapPtr autoNodeset, + virDomainDefPtr def, + virQEMUCapsPtr qemuCaps, + virQEMUDriverConfigPtr cfg, + const char **backendType, + virJSONValuePtr *backendProps, + bool force); + +char *qemuBuildMemoryDeviceStr(virDomainMemoryDefPtr mem, + virQEMUCapsPtr qemuCaps); + /* Legacy, pre device support */ char *qemuBuildPCIHostdevPCIDevStr(virDomainHostdevDefPtr dev, virQEMUCapsPtr qemuCaps); diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index e948cca..cbdf279 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -7649,8 +7649,11 @@ qemuDomainAttachDeviceLive(virDomainObjPtr vm, dev->data.rng = NULL; break; - /*TODO: implement later */ case VIR_DOMAIN_DEVICE_MEMORY: + ret = qemuDomainAttachMemory(driver, vm, + dev->data.memory); + dev->data.memory = NULL; + break;

case VIR_DOMAIN_DEVICE_NONE: case VIR_DOMAIN_DEVICE_FS: diff --git a/src/qemu/qemu_hotplug.c b/src/qemu/qemu_hotplug.c index 5c5ad0e..88c5e3c 100644 --- a/src/qemu/qemu_hotplug.c +++ b/src/qemu/qemu_hotplug.c @@ -1672,6 +1672,101 @@ qemuDomainAttachRNGDevice(virQEMUDriverPtr driver, } +/** + * qemuDomainAttachMemory: + * @driver: qemu driver data + * @vm: VM object + * @mem: Definition of the memory device to be attached. @mem is always consumed + * + * Attaches memory device described by @mem to domain @vm. + * + * Returns 0 on success -1 on error. + */ +int +qemuDomainAttachMemory(virQEMUDriverPtr driver, + virDomainObjPtr vm, + virDomainMemoryDefPtr mem) +{ + qemuDomainObjPrivatePtr priv = vm->privateData; + virQEMUDriverConfigPtr cfg = virQEMUDriverGetConfig(driver); + char *devstr = NULL; + char *objalias = NULL; + const char *backendType; + virJSONValuePtr props = NULL; + int id; + int ret = -1; + + if (virAsprintf(&mem->info.alias, "dimm%zu", vm->def->nmems) < 0) + goto cleanup; + + if (virAsprintf(&objalias, "mem%s", mem->info.alias) < 0) + goto cleanup; + + if (!(devstr = qemuBuildMemoryDeviceStr(mem, priv->qemuCaps))) + goto cleanup; + + qemuDomainMemoryDeviceAlignSize(mem); + + if (qemuBuildMemoryBackendStr(mem->size, mem->pagesize, + mem->targetNode, mem->sourceNodes, NULL, + vm->def, priv->qemuCaps, cfg, + &backendType, &props, true) < 0)

+ goto cleanup; + + if (virDomainMemoryInsert(vm->def, mem) < 0) { + virJSONValueFree(props); + goto cleanup; + } + + qemuDomainObjEnterMonitor(driver, vm); + if (qemuMonitorAddObject(priv->mon, backendType, objalias, props) < 0) + goto removedef; + + if (qemuMonitorAddDevice(priv->mon, devstr) < 0) { + virErrorPtr err = virSaveLastError(); + ignore_value(qemuMonitorDelObject(priv->mon, objalias)); + virSetError(err); + virFreeError(err); + goto removedef; + } + + if (qemuDomainObjExitMonitor(driver, vm) < 0) { + /* we shouldn't touch mem now, as the def might be freed */ + mem = NULL; + goto cleanup; + } + + /* mem is consumed by vm->def */ + mem = NULL; + + /* this step is best effort, removing the device would be so much trouble */ + ignore_value(qemuDomainUpdateMemoryDeviceInfo(driver, vm, + QEMU_ASYNC_JOB_NONE)); + + ret = 0; + + cleanup: + virObjectUnref(cfg); + VIR_FREE(devstr); + VIR_FREE(objalias); + virDomainMemoryDefFree(mem); + return ret; + + removedef: + if (qemuDomainObjExitMonitor(driver, vm) < 0) { + mem = NULL; + goto cleanup; + } + + if ((id = virDomainMemoryFindByDef(vm->def, mem)) >= 0) + mem = virDomainMemoryRemove(vm->def, id); + else + mem = NULL; + + goto cleanup; +} + + static int qemuDomainAttachHostUSBDevice(virQEMUDriverPtr driver, virDomainObjPtr vm, diff --git a/src/qemu/qemu_hotplug.h b/src/qemu/qemu_hotplug.h index 8a0b313..ad4ff38 100644 --- a/src/qemu/qemu_hotplug.h +++ b/src/qemu/qemu_hotplug.h @@ -57,6 +57,9 @@ int qemuDomainAttachHostDevice(virConnectPtr conn, virDomainHostdevDefPtr hostdev); int qemuDomainFindGraphicsIndex(virDomainDefPtr def, virDomainGraphicsDefPtr dev); +int qemuDomainAttachMemory(virQEMUDriverPtr driver, + virDomainObjPtr vm, + virDomainMemoryDefPtr mem); int qemuDomainChangeGraphics(virQEMUDriverPtr driver, virDomainObjPtr vm, virDomainGraphicsDefPtr dev);