[cinder-csi-plugin] Cleanup: handle errors from GetDevicePath

pkg/csi/cinder/nodeserver.go

@@ -191,8 +191,8 @@ func nodePublishEphemeral(req *csi.NodePublishVolumeRequest, ns *nodeServer) (*c
 	m := ns.Mount
 
 	devicePath, err := getDevicePath(evol.ID, m)
-	if devicePath == "" {
-		return nil, status.Error(codes.Internal, "Unable to find Device path for volume")
+	if err != nil {
+		return nil, status.Error(codes.Internal, fmt.Sprintf("Unable to find Device path for volume: %v", err))
 	}
 
 	targetPath := req.GetTargetPath()
@@ -237,8 +237,8 @@ func nodePublishVolumeForBlock(req *csi.NodePublishVolumeRequest, ns *nodeServer
 
 	// Do not trust the path provided by cinder, get the real path on node
 	source, err := getDevicePath(volumeID, m)
-	if source == "" {
-		return nil, status.Error(codes.Internal, "Unable to find Device path for volume")
+	if err != nil {
+		return nil, status.Error(codes.Internal, fmt.Sprintf("Unable to find Device path for volume: %v", err))
 	}
 
 	exists, err := utilpath.Exists(utilpath.CheckFollowSymlink, podVolumePath)
@@ -377,8 +377,8 @@ func (ns *nodeServer) NodeStageVolume(ctx context.Context, req *csi.NodeStageVol
 	m := ns.Mount
 	// Do not trust the path provided by cinder, get the real path on node
 	devicePath, err := getDevicePath(volumeID, m)
-	if devicePath == "" {
-		return nil, status.Error(codes.Internal, "Unable to find Device path for volume")
+	if err != nil {
+		return nil, status.Error(codes.Internal, fmt.Sprintf("Unable to find Device path for volume: %v", err))
 	}
 
 	if blk := volumeCapability.GetBlock(); blk != nil {
@@ -555,10 +555,19 @@ func (ns *nodeServer) NodeExpandVolume(ctx context.Context, req *csi.NodeExpandV
 
 func getDevicePath(volumeID string, m mount.IMount) (string, error) {
 	var devicePath string
-	devicePath, _ = m.GetDevicePath(volumeID)
+	devicePath, err := m.GetDevicePath(volumeID)
+	if err != nil {
+		klog.Warningf("Couldn't get device path from mount: %v", err)
+	}
+
 	if devicePath == "" {
 		// try to get from metadata service
-		devicePath = metadata.GetDevicePath(volumeID)
+		klog.Info("Trying to get device path from metadata service")
+		devicePath, err = metadata.GetDevicePath(volumeID)
+		if err != nil {
+			klog.Errorf("Couldn't get device path from metadata service: %v", err)
+			return "", fmt.Errorf("couldn't get device path from metadata service: %v", err)
+		}
 	}
 
 	return devicePath, nil

pkg/util/metadata/metadata.go

@@ -207,18 +207,17 @@ func getFromMetadataService(metadataVersion string) (*Metadata, error) {
 }
 
 // GetDevicePath retrieves device path from metadata service
-func GetDevicePath(volumeID string) string {
+func GetDevicePath(volumeID string) (string, error) {
 	// Nova Hyper-V hosts cannot override disk SCSI IDs. In order to locate
 	// volumes, we're querying the metadata service. Note that the Hyper-V
 	// driver will include device metadata for untagged volumes as well.
 	//
 	// We're avoiding using cached metadata (or the configdrive),
 	// relying on the metadata service.
 	instanceMetadata, err := getFromMetadataService(defaultMetadataVersion)
-
 	if err != nil {
-		klog.V(4).Infof("Could not retrieve instance metadata. Error: %v", err)
-		return ""
+		klog.Errorf("Could not retrieve instance metadata: %v", err)
+		return "", fmt.Errorf("could not retrieve instance metadata: %v", err)
 	}
 
 	for _, device := range instanceMetadata.Devices {
@@ -230,24 +229,27 @@ func GetDevicePath(volumeID string) string {
 			diskPattern := fmt.Sprintf("/dev/disk/by-path/*-%s-%s", device.Bus, device.Address)
 			diskPaths, err := filepath.Glob(diskPattern)
 			if err != nil {
-				klog.Errorf(
-					"could not retrieve disk path for volumeID: %q. Error filepath.Glob(%q): %v",
+				klog.Errorf("Could not retrieve disk path for volumeID: %q. Error filepath.Glob(%q): %v",
+					volumeID, diskPattern, err)
+				return "", fmt.Errorf("could not retrieve disk path for volumeID: %q. Error filepath.Glob(%q): %v",
 					volumeID, diskPattern, err)
-				return ""
 			}
 
 			if len(diskPaths) == 1 {
-				return diskPaths[0]
+				if diskPaths[0] == "" {
+					klog.Errorf("Disk path for volumeID %q is empty", volumeID)
+					return "", fmt.Errorf("disk path for volumeID %q is empty", volumeID)
+				}
+				return diskPaths[0], nil
 			}
 
-			klog.V(4).Infof("expecting to find one disk path for volumeID %q, found %d: %v",
+			klog.Warningf("Expecting to find one disk path for volumeID %q, found %d: %v",
 				volumeID, len(diskPaths), diskPaths)
-
 		}
 	}
 
-	klog.V(4).Infof("Could not retrieve device metadata for volumeID: %q", volumeID)
-	return ""
+	klog.Errorf("Could not retrieve device metadata for volumeID: %q", volumeID)
+	return "", fmt.Errorf("could not retrieve device metadata for volumeID: %q", volumeID)
 }
 
 // Get retrieves metadata from either config drive or metadata service.