From 3fd4c0167f1aacbf3944363b23b51b7d31767129 Mon Sep 17 00:00:00 2001
From: Dean Roehrich <dean.roehrich@hpe.com>
Date: Fri, 12 Apr 2024 12:09:01 -0500
Subject: [PATCH] Verify that the volume is not yet mounted on the target.
 (#71)

Signed-off-by: Dean Roehrich <dean.roehrich@hpe.com>
---
 pkg/lustre-driver/service/node.go | 38 ++++++++++++++++++++++---------
 1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/pkg/lustre-driver/service/node.go b/pkg/lustre-driver/service/node.go
index ca150d1..49032a3 100644
--- a/pkg/lustre-driver/service/node.go
+++ b/pkg/lustre-driver/service/node.go
@@ -1,5 +1,5 @@
 /*
- * Copyright 2021, 2022 Hewlett Packard Enterprise Development LP
+ * Copyright 2021, 2022, 2024 Hewlett Packard Enterprise Development LP
  * Other additional copyright holders may be indicated within.
  *
  * The entirety of this work is licensed under the Apache License,
@@ -73,18 +73,34 @@ func (s *service) NodePublishVolume(
 		return nil, status.Errorf(codes.Internal, "NodePublishVolume - Mountpoint mkdir Failed: Error %v", err)
 	}
 
-	// 2. Perform the mount
+	// 2. Verify that it's not yet mounted.
 	mounter := mount.New("")
-	err = mounter.Mount(
-		req.GetVolumeId(),
-		req.GetTargetPath(),
-		req.GetVolumeCapability().GetMount().GetFsType(),
-		req.GetVolumeCapability().GetMount().GetMountFlags())
-
+	isMounted := false
+	mountpoints, err := mounter.List()
 	if err != nil {
-		return nil, status.Errorf(codes.Internal, "NodePublishVolume - Mount Failed: Error %v", err)
-	} else {
-		log.WithField("source", req.GetVolumeId()).WithField("target", req.GetTargetPath()).Info("Mounted")
+		return nil, status.Errorf(codes.Internal, "NodePublishVolume - List mounts failed: Error %v", err)
+	}
+	for idx := range mountpoints {
+		if mountpoints[idx].Path == req.GetTargetPath() && mountpoints[idx].Device == req.GetVolumeId() {
+			log.WithField("source", req.GetVolumeId()).WithField("target", req.GetTargetPath()).Info("Already mounted")
+			isMounted = true
+			break
+		}
+	}
+
+	// 3. Perform the mount.
+	if !isMounted {
+		err := mounter.Mount(
+			req.GetVolumeId(),
+			req.GetTargetPath(),
+			req.GetVolumeCapability().GetMount().GetFsType(),
+			req.GetVolumeCapability().GetMount().GetMountFlags())
+
+		if err != nil {
+			return nil, status.Errorf(codes.Internal, "NodePublishVolume - Mount Failed: Error %v", err)
+		} else {
+			log.WithField("source", req.GetVolumeId()).WithField("target", req.GetTargetPath()).Info("Mounted")
+		}
 	}
 
 	return &csi.NodePublishVolumeResponse{}, nil