- Introduce new flag to enable feature to prevent unauthorised volume mode conversion

- Changes to snapshot controller to read the volume mode from the PV and add it to SourceVolumeMode field in VolumeSnapshotContent

pkg/common-controller/snapshot_controller_base.go

@@ -68,6 +68,7 @@ type csiSnapshotCommonController struct {
 	resyncPeriod time.Duration
 
 	enableDistributedSnapshotting bool
+	preventVolumeModeConversion   bool
 }
 
 // NewCSISnapshotController returns a new *csiSnapshotCommonController
@@ -84,6 +85,7 @@ func NewCSISnapshotCommonController(
 	snapshotRateLimiter workqueue.RateLimiter,
 	contentRateLimiter workqueue.RateLimiter,
 	enableDistributedSnapshotting bool,
+	preventVolumeModeConversion bool,
 ) *csiSnapshotCommonController {
 	broadcaster := record.NewBroadcaster()
 	broadcaster.StartLogging(klog.Infof)
@@ -138,6 +140,8 @@ func NewCSISnapshotCommonController(
 		ctrl.nodeListerSynced = nodeInformer.Informer().HasSynced
 	}
 
+	ctrl.preventVolumeModeConversion = preventVolumeModeConversion
+
 	return ctrl
 }