rbd: use StorageClass image features for temp clones and snapshots

Previously, temporary clone images (-temp) and snapshot backing images
had their features hard-coded to only layering and deep-flatten.

Inherit the image features from the parent volume (configured via
StorageClass imageFeatures) while ensuring layering and deep-flatten
are always enabled, as they are required for the flatten operation.

Signed-off-by: Praveen M <m.praveen@ibm.com>

Author: iPraveenParihar

internal/rbd/clone.go

@@ -109,9 +109,11 @@ func (rv *rbdVolume) checkCloneImage(ctx context.Context, parentVol *rbdVolume)
 func (rv *rbdVolume) generateTempClone() *rbdVolume {
 	tempClone := rbdVolume{}
 	tempClone.conn = rv.conn.Copy()
-	// The temp clone image need to have deep flatten feature
+	// Use the parent volume's image features (from StorageClass) and ensure
+	// that layering and deep-flatten are always enabled, as these are
+	// required for the flatten operation on the temporary clone.
 	f := []string{librbd.FeatureNameLayering, librbd.FeatureNameDeepFlatten}
-	tempClone.ImageFeatureSet = librbd.FeatureSetFromNames(f)
+	tempClone.ImageFeatureSet = rv.ImageFeatureSet | librbd.FeatureSetFromNames(f)
 	tempClone.ClusterID = rv.ClusterID
 	tempClone.Monitors = rv.Monitors
 	tempClone.Pool = rv.Pool

internal/rbd/controllerserver.go

@@ -1391,9 +1391,10 @@ func (cs *ControllerServer) doSnapshotClone(
 	// generate cloned volume details from snapshot
 	cloneRbd := rbdSnap.toVolume()
 	defer cloneRbd.Destroy(ctx)
-	// add image feature for cloneRbd
+	// Use the parent volume's image features and ensure that layering and
+	// deep-flatten are always enabled for the snapshot backing image.
 	f := []string{librbd.FeatureNameLayering, librbd.FeatureNameDeepFlatten}
-	cloneRbd.ImageFeatureSet = librbd.FeatureSetFromNames(f)
+	cloneRbd.ImageFeatureSet = parentVol.ImageFeatureSet | librbd.FeatureSetFromNames(f)
 
 	// For snapshot creation, the temporary clone must use the same data pool as the parent
 	// volume to ensure correct storage placement for erasure-coded pools.

internal/rbd/snapshot.go

@@ -292,9 +292,10 @@ func (rv *rbdVolume) NewSnapshotByID(
 		return nil, err
 	}
 
-	// set the features for the clone image.
+	// Use the parent volume's image features and ensure that layering and
+	// deep-flatten are always enabled for the snapshot backing image.
 	f := []string{librbd.FeatureNameLayering, librbd.FeatureNameDeepFlatten}
-	rv.ImageFeatureSet = librbd.FeatureSetFromNames(f)
+	rv.ImageFeatureSet |= librbd.FeatureSetFromNames(f)
 
 	options, err := rv.constructImageOptions(ctx)
 	if err != nil {