Re: [libvirt] [PATCH] snapshot: affect persistent xml after disk snapshot

On 09/16/2011 10:11 PM, Eric Blake wrote: >For external snapshots to be useful on persistent domains, we must >alter the persistent definition alongside the running definition. >Thanks to the possibility of disk hotplug as well as of edits that >only affect the persistent xml, we can't assume that vm->def and >vm->newDef have the same disk at the same index, so we can only >update the persistent copy if the device destination matches up. > >* src/qemu/qemu_driver.c (qemuDomainSnapshotCreateDiskActive) >(qemuDomainSnapshotCreateSingleDiskActive): Also affect newDef, if >present. >--- > >This is worth including in 0.9.5 - without it, the new feature of >disk snapshots on a persistent domain are lost the moment the domain >stops running, which is likely to cause data corruption for guests. I'm squashing this in, so that the persistent changes are preserved over libvirtd restarts. diff --git i/src/qemu/qemu_driver.c w/src/qemu/qemu_driver.c index cbe28d8..2a1e5ea 100644 --- i/src/qemu/qemu_driver.c +++ w/src/qemu/qemu_driver.c @@ -9221,6 +9221,7 @@ qemuDomainSnapshotCreateDiskActive(virConnectPtr conn, bool resume = false; int ret = -1; int i; + bool persist = false; if (qemuDomainObjBeginJobWithDriver(driver, vm, QEMU_JOB_MODIFY) < 0) return -1; @@ -9259,8 +9260,10 @@ qemuDomainSnapshotCreateDiskActive(virConnectPtr conn, int indx = virDomainDiskIndexByName(vm->newDef, vm->def->disks[i]->dst, false); - if (indx >= 0) + if (indx >= 0) { persistDisk = vm->newDef->disks[indx]; + persist = true; + } } ret = qemuDomainSnapshotCreateSingleDiskActive(driver, vm, @@ -9301,7 +9304,9 @@ cleanup: } if (vm) { - if (virDomainSaveStatus(driver->caps, driver->stateDir, vm) < 0) + if (virDomainSaveStatus(driver->caps, driver->stateDir, vm) < 0 || + (persist && + virDomainSaveConfig(driver->configDir, vm->newDef) < 0)) ret = -1; if (qemuDomainObjEndJob(driver, vm) == 0) { /* Only possible if a transient vm quit while our locks were down,