From 404e011ae9936beaea3264927de976cdea0b3969 Mon Sep 17 00:00:00 2001
From: Rakshith R <rar@redhat.com>
Date: Tue, 15 Jun 2021 17:55:29 +0530
Subject: [PATCH] cleanup: added helper func isNotMountPoint

Added helper func isNotMountPoint to check mountPoint,
validate error and reduce complexity of NodeStageVolume.

Signed-off-by: Rakshith R <rar@redhat.com>
---
 internal/rbd/nodeserver.go |  9 +++------
 internal/rbd/rbd_util.go   | 11 +++++++++++
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/internal/rbd/nodeserver.go b/internal/rbd/nodeserver.go
index fbabe370f..ca84ea1e2 100644
--- a/internal/rbd/nodeserver.go
+++ b/internal/rbd/nodeserver.go
@@ -154,14 +154,11 @@ func (ns *NodeServer) NodeStageVolume(ctx context.Context, req *csi.NodeStageVol
 		}
 	}
 
-	var isNotMnt bool
 	// check if stagingPath is already mounted
-	isNotMnt, err = mount.IsNotMountPoint(ns.mounter, stagingTargetPath)
-	if err != nil && !os.IsNotExist(err) {
+	isNotMnt, err := isNotMountPoint(ns.mounter, stagingTargetPath)
+	if err != nil {
 		return nil, status.Error(codes.Internal, err.Error())
-	}
-
-	if !isNotMnt {
+	} else if !isNotMnt {
 		util.DebugLog(ctx, "rbd: volume %s is already mounted to %s, skipping", volID, stagingTargetPath)
 		return &csi.NodeStageVolumeResponse{}, nil
 	}
diff --git a/internal/rbd/rbd_util.go b/internal/rbd/rbd_util.go
index ad590f606..982880608 100644
--- a/internal/rbd/rbd_util.go
+++ b/internal/rbd/rbd_util.go
@@ -38,6 +38,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/cloud-provider/volume/helpers"
+	mount "k8s.io/mount-utils"
 )
 
 const (
@@ -455,6 +456,16 @@ func checkImageFeatures(imageFeatures string, ok, static bool) bool {
 	return static && (!ok || imageFeatures == "")
 }
 
+// isNotMountPoint checks whether MountPoint does not exists and
+// also discards error indicating mountPoint exists.
+func isNotMountPoint(mounter mount.Interface, stagingTargetPath string) (bool, error) {
+	isNotMnt, err := mount.IsNotMountPoint(mounter, stagingTargetPath)
+	if os.IsNotExist(err) {
+		err = nil
+	}
+	return isNotMnt, err
+}
+
 // addRbdManagerTask adds a ceph manager task to execute command
 // asynchronously. If command is not found returns a bool set to false
 // example arg ["trash", "remove","pool/image"].