qemu: backup: Propagate bitmap metadata into qemuBackupDiskPrepareOneBitmapsChain

The function will require the bitmap topology for the full
implementation. To facilitate testing, add the propagation of the
necessary data beforehand so that the test code can stay unchanged
during the changes.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

src/qemu/qemu_backup.c

@@ -172,7 +172,9 @@ qemuBackupDiskDataCleanup(virDomainObjPtr vm,
 
 static virJSONValuePtr
 qemuBackupDiskPrepareOneBitmapsChain(virDomainMomentDefPtr *incremental,
-                                     virStorageSourcePtr backingChain)
+                                     virStorageSourcePtr backingChain,
+                                     virHashTablePtr blockNamedNodeData G_GNUC_UNUSED,
+                                     const char *diskdst G_GNUC_UNUSED)
 {
     g_autoptr(virJSONValue) ret = NULL;
 
@@ -198,13 +200,16 @@ qemuBackupDiskPrepareOneBitmapsChain(virDomainMomentDefPtr *incremental,
 static int
 qemuBackupDiskPrepareOneBitmaps(struct qemuBackupDiskData *dd,
                                 virJSONValuePtr actions,
-                                virDomainMomentDefPtr *incremental)
+                                virDomainMomentDefPtr *incremental,
+                                virHashTablePtr blockNamedNodeData)
 {
     g_autoptr(virJSONValue) mergebitmaps = NULL;
     g_autoptr(virJSONValue) mergebitmapsstore = NULL;
 
     if (!(mergebitmaps = qemuBackupDiskPrepareOneBitmapsChain(incremental,
-                                                              dd->domdisk->src)))
+                                                              dd->domdisk->src,
+                                                              blockNamedNodeData,
+                                                              dd->domdisk->dst)))
         return -1;
 
     if (!(mergebitmapsstore = virJSONValueCopy(mergebitmaps)))
@@ -246,6 +251,7 @@ qemuBackupDiskPrepareDataOne(virDomainObjPtr vm,
                              struct qemuBackupDiskData *dd,
                              virJSONValuePtr actions,
                              virDomainMomentDefPtr *incremental,
+                             virHashTablePtr blockNamedNodeData,
                              virQEMUDriverConfigPtr cfg,
                              bool removeStore)
 {
@@ -274,7 +280,8 @@ qemuBackupDiskPrepareDataOne(virDomainObjPtr vm,
     if (incremental) {
         dd->incrementalBitmap = g_strdup_printf("backup-%s", dd->domdisk->dst);
 
-        if (qemuBackupDiskPrepareOneBitmaps(dd, actions, incremental) < 0)
+        if (qemuBackupDiskPrepareOneBitmaps(dd, actions, incremental,
+                                            blockNamedNodeData) < 0)
             return -1;
     }
 
@@ -337,6 +344,7 @@ static ssize_t
 qemuBackupDiskPrepareData(virDomainObjPtr vm,
                           virDomainBackupDefPtr def,
                           virDomainMomentDefPtr *incremental,
+                          virHashTablePtr blockNamedNodeData,
                           virJSONValuePtr actions,
                           virQEMUDriverConfigPtr cfg,
                           struct qemuBackupDiskData **rdd,
@@ -359,7 +367,8 @@ qemuBackupDiskPrepareData(virDomainObjPtr vm,
         ndisks++;
 
         if (qemuBackupDiskPrepareDataOne(vm, backupdisk, dd, actions,
-                                         incremental, cfg, removeStore) < 0)
+                                         incremental, blockNamedNodeData,
+                                         cfg, removeStore) < 0)
             goto error;
 
         if (def->type == VIR_DOMAIN_BACKUP_TYPE_PULL) {
@@ -745,8 +754,14 @@ qemuBackupBegin(virDomainObjPtr vm,
             goto endjob;
     }
 
-    if ((ndd = qemuBackupDiskPrepareData(vm, def, incremental, actions, cfg, &dd,
-                                         reuse)) <= 0) {
+    if (qemuDomainObjEnterMonitorAsync(priv->driver, vm, QEMU_ASYNC_JOB_BACKUP) < 0)
+        goto endjob;
+    blockNamedNodeData = qemuMonitorBlockGetNamedNodeData(priv->mon);
+    if (qemuDomainObjExitMonitor(priv->driver, vm) < 0 || !blockNamedNodeData)
+        goto endjob;
+
+    if ((ndd = qemuBackupDiskPrepareData(vm, def, incremental, blockNamedNodeData,
+                                         actions, cfg, &dd, reuse)) <= 0) {
         if (ndd == 0) {
             virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
                            _("no disks selected for backup"));
@@ -755,12 +770,6 @@ qemuBackupBegin(virDomainObjPtr vm,
         goto endjob;
     }
 
-    if (qemuDomainObjEnterMonitorAsync(priv->driver, vm, QEMU_ASYNC_JOB_BACKUP) < 0)
-        goto endjob;
-    blockNamedNodeData = qemuMonitorBlockGetNamedNodeData(priv->mon);
-    if (qemuDomainObjExitMonitor(priv->driver, vm) < 0 || !blockNamedNodeData)
-        goto endjob;
-
     if (qemuBackupDiskPrepareStorage(vm, dd, ndd, blockNamedNodeData, reuse) < 0)
         goto endjob;