Resize CephFS Volumes

This feature enables CephFS Volume expansion on demand
based on the CO resizer request.

Signed-off-by: Humble Chirammal <hchiramm@redhat.com>

pkg/cephfs/controllerserver.go

@@ -292,3 +292,39 @@ func (cs *ControllerServer) ValidateVolumeCapabilities(
 		},
 	}, nil
 }
+
+// ExpandVolume expand CephFS Volumes on demand based on resizer request
+func (cs *ControllerServer) ControllerExpandVolume(ctx context.Context, req *csi.ControllerExpandVolumeRequest) (*csi.ControllerExpandVolumeResponse, error) {
+
+	if err := cs.validateExpandVolumeRequest(req); err != nil {
+		klog.Errorf("ControllerExpandVolumeRequest validation failed: %v", err)
+		return nil, err
+	}
+
+	volID := req.GetVolumeId()
+	secret := req.GetSecrets()
+
+	cr, err := util.NewAdminCredentials(secret)
+	if err != nil {
+		return nil, status.Error(codes.InvalidArgument, err.Error())
+	}
+	defer cr.DeleteCredentials()
+
+	volOptions, volIdentifier, err := newVolumeOptionsFromVolID(ctx, volID, nil, secret)
+
+	if err != nil {
+		klog.Errorf("validation and extraction of volume options failed: %v", err)
+		return nil, status.Error(codes.InvalidArgument, err.Error())
+	}
+
+	if err = createVolume(ctx, volOptions, cr, volumeID(volIdentifier.FsSubvolName), req.GetCapacityRange().GetRequiredBytes()); err != nil {
+		klog.Errorf("failed to expand volume %s: %v", volumeID(volIdentifier.FsSubvolName), err)
+		return nil, status.Error(codes.Internal, err.Error())
+	}
+
+	return &csi.ControllerExpandVolumeResponse{
+		CapacityBytes:         req.GetCapacityRange().GetRequiredBytes(),
+		NodeExpansionRequired: false,
+	}, nil
+
+}

pkg/cephfs/driver.go

@@ -134,6 +134,7 @@ func (fs *Driver) Run(conf *util.Config, cachePersister util.CachePersister) {
 	if conf.IsControllerServer || !conf.IsNodeServer {
 		fs.cd.AddControllerServiceCapabilities([]csi.ControllerServiceCapability_RPC_Type{
 			csi.ControllerServiceCapability_RPC_CREATE_DELETE_VOLUME,
+			csi.ControllerServiceCapability_RPC_EXPAND_VOLUME,
 		})
 
 		fs.cd.AddVolumeCapabilityAccessModes([]csi.VolumeCapability_AccessMode_Mode{

pkg/cephfs/identityserver.go

@@ -41,6 +41,13 @@ func (is *IdentityServer) GetPluginCapabilities(ctx context.Context, req *csi.Ge
 					},
 				},
 			},
+			{
+				Type: &csi.PluginCapability_VolumeExpansion_{
+					VolumeExpansion: &csi.PluginCapability_VolumeExpansion{
+						Type: csi.PluginCapability_VolumeExpansion_ONLINE,
+					},
+				},
+			},
 		},
 	}, nil
 }

pkg/cephfs/util.go

@@ -114,3 +114,21 @@ func (cs *ControllerServer) validateDeleteVolumeRequest() error {
 
 	return nil
 }
+
+// Controller expand volume request validation
+func (cs *ControllerServer) validateExpandVolumeRequest(req *csi.ControllerExpandVolumeRequest) error {
+	if err := cs.Driver.ValidateControllerServiceRequest(csi.ControllerServiceCapability_RPC_EXPAND_VOLUME); err != nil {
+		return fmt.Errorf("invalid ExpandVolumeRequest: %v", err)
+	}
+
+	if req.GetVolumeId() == "" {
+		return status.Error(codes.InvalidArgument, "Volume ID cannot be empty")
+	}
+
+	capRange := req.GetCapacityRange()
+	if capRange == nil {
+		return status.Error(codes.InvalidArgument, "CapacityRange cannot be empty")
+	}
+
+	return nil
+}