[libvirt] [PATCH 5/5] qemu: snapshot: Load data necessary for relative block commit to work
Commit 7456c4f5f introduced a regression by not reloading the backing
chain of a disk after snapshot. The regression was caused as
src->relPath was not set and thus the block commit code could not
determine the relative path.
This patch adds code that will load the backing store string if
VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT and store it in the correct place
when a snapshot is successfully completed.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1461303
---
src/qemu/qemu_driver.c | 19 +++++++++++++++++--
1 file changed, 17 insertions(+), 2 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index 4f62c1a7a..e91663ca9 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -14091,6 +14091,7 @@ struct _qemuDomainSnapshotDiskData {
bool created; /* @src was created by the snapshot code */
bool prepared; /* @src was prepared using qemuDomainDiskChainElementPrepare */
virDomainDiskDefPtr disk;
+ char *relPath; /* relative path component to fill into original disk */
virStorageSourcePtr persistsrc;
virDomainDiskDefPtr persistdisk;
@@ -14124,6 +14125,7 @@ qemuDomainSnapshotDiskDataFree(qemuDomainSnapshotDiskDataPtr
data,
virStorageSourceFree(data[i].src);
}
virStorageSourceFree(data[i].persistsrc);
+ VIR_FREE(data[i].relPath);
}
VIR_FREE(data);
@@ -14139,11 +14141,13 @@ qemuDomainSnapshotDiskDataFree(qemuDomainSnapshotDiskDataPtr
data,
static qemuDomainSnapshotDiskDataPtr
qemuDomainSnapshotDiskDataCollect(virQEMUDriverPtr driver,
virDomainObjPtr vm,
- virDomainSnapshotObjPtr snap)
+ virDomainSnapshotObjPtr snap,
+ bool reuse)
{
size_t i;
qemuDomainSnapshotDiskDataPtr ret;
qemuDomainSnapshotDiskDataPtr dd;
+ char *backingStoreStr;
if (VIR_ALLOC_N(ret, snap->def->ndisks) < 0)
return NULL;
@@ -14167,6 +14171,16 @@ qemuDomainSnapshotDiskDataCollect(virQEMUDriverPtr driver,
dd->initialized = true;
+ /* relative backing store paths need to be updated so that relative
+ * block commit still works */
+ if (reuse &&
+ (backingStoreStr = virStorageFileGetBackingStoreStr(dd->src))) {
+ if (virStorageIsRelative(backingStoreStr))
+ VIR_STEAL_PTR(dd->relPath, backingStoreStr);
+ else
+ VIR_FREE(backingStoreStr);
+ }
+
/* Note that it's unsafe to assume that the disks in the persistent
* definition match up with the disks in the live definition just by
* checking that the target name is the same. We've done that
@@ -14210,6 +14224,7 @@ qemuDomainSnapshotUpdateDiskSources(qemuDomainSnapshotDiskDataPtr
dd,
if (dd->initialized)
virStorageFileDeinit(dd->src);
+ VIR_STEAL_PTR(dd->disk->src->relPath, dd->relPath);
VIR_STEAL_PTR(dd->src->backingStore, dd->disk->src);
VIR_STEAL_PTR(dd->disk->src, dd->src);
@@ -14323,7 +14338,7 @@ qemuDomainSnapshotCreateDiskActive(virQEMUDriverPtr driver,
/* prepare a list of objects to use in the vm definition so that we don't
* have to roll back later */
- if (!(diskdata = qemuDomainSnapshotDiskDataCollect(driver, vm, snap)))
+ if (!(diskdata = qemuDomainSnapshotDiskDataCollect(driver, vm, snap, reuse)))
goto cleanup;
cfg = virQEMUDriverGetConfig(driver);
--
2.12.2