Re: [libvirt] [PATCHv8 1/4] libvirt/qemu - persistent modification of inactive domans.

>From 1ffbe73b1663719414367abbdebc8f31b9592331 Mon Sep 17 00:00:00 2001 From: KAMEZAWA Hiroyuki <kamezawa.hiroyu(a)jp.fujitsu.com&gt; Date: Thu, 31 Mar 2011 16:20:05 +0900 Subject: [PATCHv8 1/4] libvirt/qemu - persistent modification of devices. Now, qemudDomainAttachDeviceFlags() and qemudDomainDetachDeviceFlags() doesn't support VIR_DOMAIN_DEVICE_MODIFY_CONFIG. By this, virsh's at(de)tatch-device --persistent cannot modify qemu config. (Xen allows it.) This patch is a base patch for adding support of devices in step by step manner. Following patches will add some device support. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu(a)jp.fujitsu.com&gt; --- src/qemu/qemu_driver.c | 150 +++++++++++++++++++++++++++++++++++++++++++----- 1 files changed, 136 insertions(+), 14 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index dd12dc8..b89bc8f 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -3873,16 +3873,133 @@ cleanup: return ret; } -static int qemudDomainAttachDeviceFlags(virDomainPtr dom, - const char *xml, - unsigned int flags) { - if (flags & VIR_DOMAIN_DEVICE_MODIFY_CONFIG) { - qemuReportError(VIR_ERR_OPERATION_INVALID, - "%s", _("cannot modify the persistent configuration of a domain")); +/* + * At(de)tach a device given by XML, the change will be persistent + * and domain XML definition file is updated when these function + * returns 0(success). IOW, at failure, XML definition is never updated. + * So, this function must guarantee consistency between vmdef and its XML + * definition in the file. + */ + +static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef, + virDomainDeviceDefPtr newdev) +{ + + switch(newdev->type) { + default: + qemuReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("the device is not supported for now")); return -1; } - return qemudDomainAttachDevice(dom, xml); + return 0; +} + +static int qemuDomainDetachDevicePersistent(virDomainDefPtr vmdef, + virDomainDeviceDefPtr device) +{ + switch(device->type) { + default: + qemuReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s", + _("the device is not supported for now")); + return -1; + } + return 0; +} + +static int qemuDomainModifyDevicePersistent(virDomainPtr dom, + const char *xml, + unsigned int attach, + unsigned int flags) +{ + struct qemud_driver *driver; + virDomainDeviceDefPtr device; + virDomainDefPtr vmdef; + virDomainObjPtr vm; + int ret = -1; + + /* + * When both of MODIFY_CONFIG and MODIFY_LIVE are passed at the same time, + * return error for now. We should support this later. + */ + if (flags & VIR_DOMAIN_DEVICE_MODIFY_LIVE) { + qemuReportError(VIR_ERR_OPERATION_INVALID, "%s", + _("cannot modify active domain and its definition " + "at the same time.")); + return -1; + } + + driver = dom->conn->privateData; + qemuDriverLock(driver); + vm = virDomainFindByName(&driver->domains, dom->name); + if (!vm) { + qemuReportError(VIR_ERR_NO_DOMAIN, _("no domain with name : '%s'"), + dom->name); + goto unlock_out; + } + + if (qemuDomainObjBeginJobWithDriver(driver, vm) < 0) + goto unlock_out; + + if (virDomainObjIsActive(vm)) { + /* + * For now, just allow updating inactive domains. Further development + * will allow updating both active domain and its config file at + * the same time. + */ + qemuReportError(VIR_ERR_OPERATION_INVALID, "%s", + _("cannot modify active domain's definition")); + goto endjob; + } + + vmdef = virDomainObjGetPersistentDef(driver->caps, vm); + + if (!vmdef) + goto endjob; + + device = virDomainDeviceDefParse(driver->caps, + vmdef, xml, VIR_DOMAIN_XML_INACTIVE); + if (!device) + goto endjob; + + if (attach) + ret = qemuDomainAttachDevicePersistent(vmdef, device); + else + ret = qemuDomainDetachDevicePersistent(vmdef, device); + /* + * At(De)tachDevicePersistent() must guarantee that vmdef is consistent + * with XML definition when they returns a failure, ret != 0. + */

+ if (!ret) + ret = virDomainSaveConfig(driver->configDir, vmdef); + + virDomainDeviceDefFree(device); + +endjob: + if (qemuDomainObjEndJob(vm) == 0) + vm = NULL; +unlock_out: + if (vm) + virDomainObjUnlock(vm); + qemuDriverUnlock(driver); + return ret; +} + +static int qemudDomainAttachDeviceFlags(virDomainPtr dom, + const char *xml, + unsigned int flags) +{ + int ret = -1; + + virCheckFlags((VIR_DOMAIN_DEVICE_MODIFY_CONFIG | + VIR_DOMAIN_DEVICE_MODIFY_LIVE), -1); + + if (flags & VIR_DOMAIN_DEVICE_MODIFY_CONFIG) + ret = qemuDomainModifyDevicePersistent(dom, xml, 1, flags); + else if (flags & VIR_DOMAIN_DEVICE_MODIFY_LIVE) + ret = qemudDomainAttachDevice(dom, xml); + + return ret; } @@ -4096,14 +4213,19 @@ cleanup: static int qemudDomainDetachDeviceFlags(virDomainPtr dom, const char *xml, - unsigned int flags) { - if (flags & VIR_DOMAIN_DEVICE_MODIFY_CONFIG) { - qemuReportError(VIR_ERR_OPERATION_INVALID, - "%s", _("cannot modify the persistent configuration of a domain")); - return -1; - } + unsigned int flags) +{ + int ret = -1; + + virCheckFlags((VIR_DOMAIN_DEVICE_MODIFY_CONFIG | + VIR_DOMAIN_DEVICE_MODIFY_LIVE), -1); - return qemudDomainDetachDevice(dom, xml); + if (flags & VIR_DOMAIN_DEVICE_MODIFY_CONFIG) + ret = qemuDomainModifyDevicePersistent(dom, xml, 0, flags); + else if (flags & VIR_DOMAIN_DEVICE_MODIFY_LIVE) + ret = qemudDomainDetachDevice(dom, xml); + + return ret; } static int qemudDomainGetAutostart(virDomainPtr dom,