From b7f6911b03db258a9a50022f0f7b0dbaf15d15a5 Mon Sep 17 00:00:00 2001
From: Akhil Mohan <akhil.mohan@mayadata.io>
Date: Tue, 29 Dec 2020 09:40:43 +0530
Subject: [PATCH] feat(filter): add support for using unused partition on
 os-disk

Signed-off-by: Akhil Mohan <akhil.mohan@mayadata.io>
---
 .../filter/osdiskexcludefilter.go              |  2 --
 pkg/mount/mountutil.go                         | 18 ++++++++++++++----
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/cmd/ndm_daemonset/filter/osdiskexcludefilter.go b/cmd/ndm_daemonset/filter/osdiskexcludefilter.go
index 7d2309120..c31c14253 100644
--- a/cmd/ndm_daemonset/filter/osdiskexcludefilter.go
+++ b/cmd/ndm_daemonset/filter/osdiskexcludefilter.go
@@ -90,7 +90,6 @@ func (odf *oSDiskExcludeFilter) Start() {
 		mountPointUtil := mount.NewMountUtil(hostMountFilePath, "", mountPoint)
 		if devPath, err := mountPointUtil.GetDiskPath(); err != nil {
 			klog.Errorf("unable to configure os disk filter for mountpoint: %s, error: %v", mountPoint, err)
-			klog.Error(err)
 		} else {
 			odf.excludeDevPaths = append(odf.excludeDevPaths, devPath)
 		}
@@ -103,7 +102,6 @@ func (odf *oSDiskExcludeFilter) Start() {
 		mountPointUtil := mount.NewMountUtil(defaultMountFilePath, "", mountPoint)
 		if devPath, err := mountPointUtil.GetDiskPath(); err != nil {
 			klog.Errorf("unable to configure os disk filter for mountpoint: %s, error: %v", mountPoint, err)
-			klog.Error(err)
 		} else {
 			odf.excludeDevPaths = append(odf.excludeDevPaths, devPath)
 		}
diff --git a/pkg/mount/mountutil.go b/pkg/mount/mountutil.go
index b0e2aabba..432ad183d 100644
--- a/pkg/mount/mountutil.go
+++ b/pkg/mount/mountutil.go
@@ -19,6 +19,7 @@ package mount
 import (
 	"bufio"
 	"fmt"
+	"github.com/openebs/node-disk-manager/pkg/features"
 	"io"
 	"os"
 	"path/filepath"
@@ -116,11 +117,20 @@ func getDiskDevPath(partition string) (string, error) {
 		return "", err
 	}
 
-	parentDisk, ok := getParentBlockDevice(link)
-	if !ok {
-		return "", fmt.Errorf("could not find parent device for %s", link)
+	var disk string
+	var ok bool
+	if features.FeatureGates.IsEnabled(features.UseOSDisk) {
+		// the last part will be used instead of the parent disk
+		split := strings.Split(link, "/")
+		disk = split[len(split)-1]
+	} else {
+		disk, ok = getParentBlockDevice(link)
+		if !ok {
+			return "", fmt.Errorf("could not find parent device for %s", link)
+		}
 	}
-	return "/dev/" + parentDisk, nil
+
+	return "/dev/" + disk, nil
 }
 
 //	getSoftLinkForPartition returns path to /sys/class/block/$partition