[libvirt-users] [PATCH 1/2] libvirt/qemu : allow persistent modification of disks via A(De)ttachDeviceFlags

From: KAMEZAWA Hiroyuki <kamezawa(a)bluextal.(none)&gt; Date: Wed, 23 Feb 2011 15:25:26 +0900 Subject: [PATCH 1/2] libvirt/qemu : support attach/detach-disk --persistent Now, only Xen supports 'virsh attach/detach-disk XXXX --persistent', modifying inactive domain definition via virsh. This patch adds a support for qemu. With this patch, virsh attach/detach-disk --persistent works well with qemu. Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu(a)jp.fujitsu.com&gt; --- src/qemu/qemu_driver.c | 170 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 files changed, 163 insertions(+), 7 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 0f25a2a..703f86a 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -4082,16 +4082,174 @@ cleanup: return ret; } +static int qemuDomainFindDiskByName(virDomainDefPtr vmdef, const char *name) +{ + virDomainDiskDefPtr vdisk; + int i; + + for (i = 0; i < vmdef->ndisks; i++) { + vdisk = vmdef->disks[i]; + if (!strcmp(vdisk->dst, name)) + return i; + } + return -1; +} +/* + * Attach a device given by XML, the change will be persistent + * and domain XML definition file is updated. + */ +static int qemuDomainAttachDevicePersistent(virDomainDefPtr vmdef, + virDomainDeviceDefPtr newdev) +{ + virDomainDiskDefPtr disk; + + /* At first, check device confliction */ + switch(newdev->type) { + case VIR_DOMAIN_DEVICE_DISK: + disk = newdev->data.disk; + if (qemuDomainFindDiskByName(vmdef, disk->dst) >= 0) { + qemuReportError(VIR_ERR_INVALID_ARG, + _("target %s already exists."), disk->dst); + return -1; + } + + if (virDomainDiskInsert(vmdef, disk)) { + virReportOOMError(); + return -1; + } + if (disk->info.type == VIR_DOMAIN_DEVICE_ADDRESS_TYPE_PCI) { + /* + * Address/Drive information is NULL. If virtio, PCI address + * shoule be fixed. Other devices as IDE, SCSI...will get ID + * automatically + */ + qemuDomainAssignPCIAddresses(vmdef); + + } + newdev->data.disk = NULL; + break; + default: + qemuReportError(VIR_ERR_INVALID_ARG, "%s", + _("Sorry, the device is not suppored for now")); + return -1; + } + + return 0; +} + +static int qemuDomainDetachDevicePersistent(virDomainDefPtr vmdef, + virDomainDeviceDefPtr device) +{ + int x; + virDomainDiskDefPtr disk; + + switch(device->type) { + case VIR_DOMAIN_DEVICE_DISK: + disk = device->data.disk; + x = qemuDomainFindDiskByName(vmdef, disk->dst); + if (x < 0) { + qemuReportError(VIR_ERR_INVALID_ARG, + _("target %s doesn't exist."), disk->dst); + return -1; + } + virDomainDiskRemove(vmdef, x); + break; + default: + qemuReportError(VIR_ERR_INVALID_ARG, "%s", + _("Sorry, the device is not suppored for now")); + return -1; + } + return 0; +} + +static int qemuDomainModifyDevicePersistent(virDomainPtr dom, + const char *xml, + unsigned int attach) +{ + struct qemud_driver *driver; + virDomainDeviceDefPtr device; + virDomainDefPtr vmdef; + virDomainObjPtr vm; + int ret = -1; + + if (!dom || !dom->conn || !dom->name || !xml) { + qemuReportError(VIR_ERR_INVALID_ARG, + _("internal error : %s"), __FUNCTION__); + return -1; + } + + if (dom->conn->flags & VIR_CONNECT_RO) + return -1; + + driver = dom->conn->privateData; + qemuDriverLock(driver); + vm = virDomainFindByUUID(&driver->domains, dom->uuid); + if (!vm) { + qemuReportError(VIR_ERR_NO_DOMAIN, _("cannot find domain '%s'"), + dom->name); + goto unlock_out; + } + + if (qemuDomainObjBeginJobWithDriver(driver, vm) < 0) { + /* + * 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_INVALID_ARG, + _("cannot update alive domain : %s"), __FUNCTION__); + 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); + if (ret < 0) + goto out; + } else { + ret = qemuDomainDetachDevicePersistent(vmdef, device); + if (ret < 0) + goto out; + } + ret = virDomainSaveConfig(driver->configDir, vmdef); + +out: + virDomainDeviceDefFree(device); +endjob: + if (qemuDomainObjEndJob(vm) == 0) + vm = NULL; + if (vm) + virDomainObjUnlock(vm); + /* Note: insert of newdev is done by copy */ +unlock_out: + qemuDriverUnlock(driver); + 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")); - return -1; + /* + * Because we can't update the live guest and XML + * in atomic, limiting modification as only-acrive and + * only-inactive. Need some idea to update both at the same time. + */ + return qemuDomainModifyDevicePersistent(dom, xml, 1); } - return qemudDomainAttachDevice(dom, xml); + if (flags & VIR_DOMAIN_DEVICE_MODIFY_LIVE) + return qemudDomainAttachDevice(dom, xml); + + return -1; } @@ -4304,9 +4462,7 @@ 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; + return qemuDomainModifyDevicePersistent(dom, xml, 0); } return qemudDomainDetachDevice(dom, xml); -- 1.7.1