qemu_snapshot: add merge to external snapshot delete prepare data

Before external snapshot revert every delete operation did block commit
in order to delete a snapshot. But now when user reverts to non-leaf
snapshot deleting leaf snapshot will not have any overlay files so we
can just simply delete the snapshot images.

Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Reviewed-by: Peter Krempa <pkrempa@redhat.com>
This commit is contained in:
Pavel Hrdina 2023-04-04 14:21:05 +02:00
parent b0876595a3
commit a3152a506b

View File

@ -2622,9 +2622,26 @@ qemuSnapshotFindParentSnapForDisk(virDomainMomentObj *snap,
}
/**
* qemuSnapshotDeleteExternalPrepareData:
* @vm: domain object
* @snap: snapshot object
* @merge: whether we are just deleting image or not
* @externalData: prepared data to delete external snapshot
*
* Validate if we can delete selected snapshot @snap and prepare all necessary
* data that will be used when deleting snapshot as @externalData.
*
* If @merge is set to true we will merge the deleted snapshot into parent one
* instead of just deleting it. This is necessary when operating on snapshot
* that has existing overlay files.
*
* Returns -1 on error, 0 on success.
*/
static int
qemuSnapshotDeleteExternalPrepareData(virDomainObj *vm,
virDomainMomentObj *snap,
bool merge,
GSList **externalData)
{
ssize_t i;
@ -2648,10 +2665,6 @@ qemuSnapshotDeleteExternalPrepareData(virDomainObj *vm,
data = g_new0(qemuSnapshotDeleteExternalData, 1);
data->snapDisk = snapDisk;
data->domDisk = qemuDomainDiskByName(vm->def, snapDisk->name);
if (!data->domDisk)
return -1;
data->parentDomDisk = virDomainDiskByTarget(snapdef->parent.dom,
data->snapDisk->name);
if (!data->parentDomDisk) {
@ -2661,39 +2674,46 @@ qemuSnapshotDeleteExternalPrepareData(virDomainObj *vm,
return -1;
}
if (virDomainObjIsActive(vm)) {
data->diskSrc = virStorageSourceChainLookupBySource(data->domDisk->src,
data->snapDisk->src,
&data->prevDiskSrc);
if (!data->diskSrc)
if (merge) {
data->domDisk = qemuDomainDiskByName(vm->def, snapDisk->name);
if (!data->domDisk)
return -1;
if (!virStorageSourceIsSameLocation(data->diskSrc, data->snapDisk->src)) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("VM disk source and snapshot disk source are not the same"));
return -1;
if (virDomainObjIsActive(vm)) {
data->diskSrc = virStorageSourceChainLookupBySource(data->domDisk->src,
data->snapDisk->src,
&data->prevDiskSrc);
if (!data->diskSrc)
return -1;
if (!virStorageSourceIsSameLocation(data->diskSrc, data->snapDisk->src)) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("VM disk source and snapshot disk source are not the same"));
return -1;
}
data->parentDiskSrc = data->diskSrc->backingStore;
if (!virStorageSourceIsBacking(data->parentDiskSrc)) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("failed to find parent disk source in backing chain"));
return -1;
}
if (!virStorageSourceIsSameLocation(data->parentDiskSrc,
data->parentDomDisk->src)) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("snapshot VM disk source and parent disk source are not the same"));
return -1;
}
}
data->parentDiskSrc = data->diskSrc->backingStore;
if (!virStorageSourceIsBacking(data->parentDiskSrc)) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("failed to find parent disk source in backing chain"));
data->parentSnap = qemuSnapshotFindParentSnapForDisk(snap, data->snapDisk);
if (data->parentSnap && !virDomainSnapshotIsExternal(data->parentSnap)) {
virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
_("deleting external snapshot that has internal snapshot as parent not supported"));
return -1;
}
if (!virStorageSourceIsSameLocation(data->parentDiskSrc, data->parentDomDisk->src)) {
virReportError(VIR_ERR_OPERATION_FAILED, "%s",
_("snapshot VM disk source and parent disk source are not the same"));
return -1;
}
}
data->parentSnap = qemuSnapshotFindParentSnapForDisk(snap, data->snapDisk);
if (data->parentSnap && !virDomainSnapshotIsExternal(data->parentSnap)) {
virReportError(VIR_ERR_OPERATION_UNSUPPORTED, "%s",
_("deleting external snapshot that has internal snapshot as parent not supported"));
return -1;
}
ret = g_slist_prepend(ret, g_steal_pointer(&data));
@ -2740,7 +2760,7 @@ qemuSnapshotDeleteExternalPrepare(virDomainObj *vm,
}
/* this also serves as validation whether the snapshot can be deleted */
if (qemuSnapshotDeleteExternalPrepareData(vm, snap, &tmpData) < 0)
if (qemuSnapshotDeleteExternalPrepareData(vm, snap, true, &tmpData) < 0)
return -1;
if (!virDomainObjIsActive(vm)) {
@ -2755,7 +2775,7 @@ qemuSnapshotDeleteExternalPrepare(virDomainObj *vm,
/* Call the prepare again as some data require that the VM is
* running to get everything we need. */
if (qemuSnapshotDeleteExternalPrepareData(vm, snap, externalData) < 0)
if (qemuSnapshotDeleteExternalPrepareData(vm, snap, true, externalData) < 0)
return -1;
} else {
qemuDomainJobPrivate *jobPriv = vm->job->privateData;