cephfs: add netNamespaceFilePath for CephFS

as same host directory is not shared between
the cephfs and the rbd plugin pod. we need
to keep the netNamespaceFilePath separately
for both cephfs and rbd. CephFS plugin will
use this path to execute mount -t commands.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

internal/cephfs/nodeserver.go

@@ -126,6 +126,12 @@ func (ns *NodeServer) NodeStageVolume(
 	}
 	defer volOptions.Destroy()
 
+	volOptions.NetNamespaceFilePath, err = util.GetCephFSNetNamespaceFilePath(
+		util.CsiConfigFile,
+		volOptions.ClusterID)
+	if err != nil {
+		return nil, status.Error(codes.Internal, err.Error())
+	}
 	mnt, err := mounter.New(volOptions)
 	if err != nil {
 		log.ErrorLog(ctx, "failed to create mounter for volume %s: %v", volID, err)

internal/util/csiconfig.go

@@ -46,6 +46,8 @@ type ClusterInfo struct {
 	Monitors []string `json:"monitors"`
 	// CephFS contains CephFS specific options
 	CephFS struct {
+		// symlink filepath for the network namespace where we need to execute commands.
+		NetNamespaceFilePath string `json:"netNamespaceFilePath"`
 		// SubvolumeGroup contains the name of the SubvolumeGroup for CSI volumes
 		SubvolumeGroup string `json:"subvolumeGroup"`
 	} `json:"cephFS"`
@@ -182,3 +184,13 @@ func GetRBDNetNamespaceFilePath(pathToConfig, clusterID string) (string, error)
 
 	return cluster.RBD.NetNamespaceFilePath, nil
 }
+
+// GetCephFSNetNamespaceFilePath returns the netNamespaceFilePath for CephFS volumes.
+func GetCephFSNetNamespaceFilePath(pathToConfig, clusterID string) (string, error) {
+	cluster, err := readClusterInfo(pathToConfig, clusterID)
+	if err != nil {
+		return "", err
+	}
+
+	return cluster.CephFS.NetNamespaceFilePath, nil
+}

internal/util/csiconfig_test.go

@@ -215,3 +215,79 @@ func TestGetRBDNetNamespaceFilePath(t *testing.T) {
 		})
 	}
 }
+
+func TestGetCephFSNetNamespaceFilePath(t *testing.T) {
+	t.Parallel()
+	tests := []struct {
+		name      string
+		clusterID string
+		want      string
+	}{
+		{
+			name:      "get cephFS specific NetNamespaceFilePath for cluster-1",
+			clusterID: "cluster-1",
+			want:      "/var/lib/kubelet/plugins/cephfs.ceph.csi.com/cluster1-net",
+		},
+		{
+			name:      "get cephFS specific NetNamespaceFilePath for cluster-2",
+			clusterID: "cluster-2",
+			want:      "/var/lib/kubelet/plugins/cephfs.ceph.csi.com/cluster2-net",
+		},
+		{
+			name:      "when cephFS specific NetNamespaceFilePath is empty",
+			clusterID: "cluster-3",
+			want:      "",
+		},
+	}
+
+	csiConfig := []ClusterInfo{
+		{
+			ClusterID: "cluster-1",
+			Monitors:  []string{"ip-1", "ip-2"},
+			CephFS: struct {
+				NetNamespaceFilePath string `json:"netNamespaceFilePath"`
+				SubvolumeGroup       string `json:"subvolumeGroup"`
+			}{
+				NetNamespaceFilePath: "/var/lib/kubelet/plugins/cephfs.ceph.csi.com/cluster1-net",
+			},
+		},
+		{
+			ClusterID: "cluster-2",
+			Monitors:  []string{"ip-3", "ip-4"},
+			CephFS: struct {
+				NetNamespaceFilePath string `json:"netNamespaceFilePath"`
+				SubvolumeGroup       string `json:"subvolumeGroup"`
+			}{
+				NetNamespaceFilePath: "/var/lib/kubelet/plugins/cephfs.ceph.csi.com/cluster2-net",
+			},
+		},
+		{
+			ClusterID: "cluster-3",
+			Monitors:  []string{"ip-5", "ip-6"},
+		},
+	}
+	csiConfigFileContent, err := json.Marshal(csiConfig)
+	if err != nil {
+		t.Errorf("failed to marshal csi config info %v", err)
+	}
+	tmpConfPath := t.TempDir() + "/ceph-csi.json"
+	err = os.WriteFile(tmpConfPath, csiConfigFileContent, 0o600)
+	if err != nil {
+		t.Errorf("failed to write %s file content: %v", CsiConfigFile, err)
+	}
+	for _, tt := range tests {
+		ts := tt
+		t.Run(ts.name, func(t *testing.T) {
+			t.Parallel()
+			got, err := GetCephFSNetNamespaceFilePath(tmpConfPath, ts.clusterID)
+			if err != nil {
+				t.Errorf("GetCephFSNetNamespaceFilePath() error = %v", err)
+
+				return
+			}
+			if got != ts.want {
+				t.Errorf("GetCephFSNetNamespaceFilePath() = %v, want %v", got, ts.want)
+			}
+		})
+	}
+}