make CephFS SubvolumeGroup configurable

The name of the CephFS SubvolumeGroup for the CSI volumes was hardcoded to "csi". To make permission management in multi tenancy environments easier, this commit makes it possible to configure the CSI SubvolumeGroup.

related to #798 and #931

charts/ceph-csi-cephfs/values.yaml

@@ -25,6 +25,8 @@ serviceAccounts:
 #     monitors:
 #       - "<MONValue1>"
 #       - "<MONValue2>"
+#     cephFS:
+#       subvolumeGroup: "csi"
 csiConfig: []
 
 nodeplugin:

e2e/utils.go

@@ -365,6 +365,15 @@ func deleteConfigMap(pluginPath string) {
 	}
 }
 
+// matches the definition in internal/util/csiconfig.go
+type clusterInfo struct {
+	ClusterID string   `json:"clusterID"`
+	Monitors  []string `json:"monitors"`
+	CephFS    struct {
+		SubvolumeGroup string `json:"subvolumeGroup"`
+	} `json:"cephFS"`
+}
+
 func createConfigMap(pluginPath string, c kubernetes.Interface, f *framework.Framework) {
 	path := pluginPath + configMap
 	cm := v1.ConfigMap{}
@@ -379,15 +388,11 @@ func createConfigMap(pluginPath string, c kubernetes.Interface, f *framework.Fra
 	fsID = strings.Trim(fsID, "\n")
 	// get mon list
 	mons := getMons(rookNamespace, c)
-	conmap := []struct {
-		Clusterid string   `json:"clusterID"`
-		Monitors  []string `json:"monitors"`
-	}{
-		{
-			fsID,
-			mons,
-		},
-	}
+	conmap := []clusterInfo{{
+		ClusterID: fsID,
+		Monitors:  mons,
+	}}
+	conmap[0].CephFS.SubvolumeGroup = "e2e"
 	data, err := json.Marshal(conmap)
 	Expect(err).Should(BeNil())
 	cm.Data["config.json"] = string(data)
@@ -1012,7 +1017,7 @@ func deleteBackingCephFSVolume(f *framework.Framework, pvc *v1.PersistentVolumeC
 	opt := metav1.ListOptions{
 		LabelSelector: "app=rook-ceph-tools",
 	}
-	_, stdErr := execCommandInPod(f, "ceph fs subvolume rm myfs "+imageData.imageName+" csi", rookNamespace, &opt)
+	_, stdErr := execCommandInPod(f, "ceph fs subvolume rm myfs "+imageData.imageName+" e2e", rookNamespace, &opt)
 	Expect(stdErr).Should(BeEmpty())
 
 	if stdErr != "" {

examples/csi-config-map-sample.yaml

@@ -12,6 +12,7 @@ kind: ConfigMap
 # each such cluster in use.
 # To add more clusters or edit MON addresses in an existing config map, use
 # the `kubectl replace` command.
+# The field "cephFS.subvolumeGroup" is optional and defaults to "csi".
 # NOTE: Changes to the config map is automatically updated in the running pods,
 # thus restarting existing pods using the config map is NOT required on edits
 # to the config map.
@@ -25,7 +26,10 @@ data:
           "<MONValue2>",
           ...
           "<MONValueN>"
-        ]
+        ],
+        "cephFS": {
+          "subvolumeGroup": "<subvolumegroup for cephfs volumes>"
+        }
       }
     ]
 metadata:

internal/cephfs/volume.go

@@ -29,10 +29,6 @@ import (
 	"k8s.io/klog"
 )
 
-const (
-	csiSubvolumeGroup = "csi"
-)
-
 var (
 	// cephfsInit is used to create "csi" subvolume group for the first time the csi plugin loads.
 	// Subvolume group create gets called every time the plugin loads, though it doesn't result in error
@@ -65,7 +61,7 @@ func getVolumeRootPathCeph(ctx context.Context, volOptions *volumeOptions, cr *u
 		volOptions.FsName,
 		string(volID),
 		"--group_name",
-		csiSubvolumeGroup,
+		volOptions.SubvolumeGroup,
 		"-m", volOptions.Monitors,
 		"-c", util.CephConfigPath,
 		"-n", cephEntityClientPrefix+cr.ID,
@@ -93,16 +89,16 @@ func createVolume(ctx context.Context, volOptions *volumeOptions, cr *util.Crede
 			"subvolumegroup",
 			"create",
 			volOptions.FsName,
-			csiSubvolumeGroup,
+			volOptions.SubvolumeGroup,
 			"-m", volOptions.Monitors,
 			"-c", util.CephConfigPath,
 			"-n", cephEntityClientPrefix+cr.ID,
 			"--keyfile="+cr.KeyFile)
 		if err != nil {
-			klog.Errorf(util.Log(ctx, "failed to create subvolume group csi, for the vol %s(%s)"), string(volID), err)
+			klog.Errorf(util.Log(ctx, "failed to create subvolume group %s, for the vol %s(%s)"), volOptions.SubvolumeGroup, string(volID), err)
 			return err
 		}
-		klog.V(4).Infof(util.Log(ctx, "cephfs: created subvolume group csi"))
+		klog.V(4).Infof(util.Log(ctx, "cephfs: created subvolume group %s"), volOptions.SubvolumeGroup)
 		cephfsInit = true
 	}
 
@@ -114,7 +110,7 @@ func createVolume(ctx context.Context, volOptions *volumeOptions, cr *util.Crede
 		string(volID),
 		strconv.FormatInt(bytesQuota, 10),
 		"--group_name",
-		csiSubvolumeGroup,
+		volOptions.SubvolumeGroup,
 		"--mode", "777",
 		"-m", volOptions.Monitors,
 		"-c", util.CephConfigPath,
@@ -212,7 +208,7 @@ func purgeVolume(ctx context.Context, volID volumeID, cr *util.Credentials, volO
 		volOptions.FsName,
 		string(volID),
 		"--group_name",
-		csiSubvolumeGroup,
+		volOptions.SubvolumeGroup,
 		"-m", volOptions.Monitors,
 		"-c", util.CephConfigPath,
 		"-n", cephEntityClientPrefix+cr.ID,

internal/cephfs/volumeoptions.go

@@ -45,6 +45,7 @@ type volumeOptions struct {
 	ProvisionVolume     bool   `json:"provisionVolume"`
 	KernelMountOptions  string `json:"kernelMountOptions"`
 	FuseMountOptions    string `json:"fuseMountOptions"`
+	SubvolumeGroup      string
 }
 
 func validateNonEmptyField(field, fieldName string) error {
@@ -109,24 +110,30 @@ func extractMounter(dest *string, options map[string]string) error {
 	return nil
 }
 
-func getMonsAndClusterID(options map[string]string) (string, string, error) {
+func getClusterInformation(options map[string]string) (string, string, string, error) {
 	clusterID, ok := options["clusterID"]
 	if !ok {
 		err := fmt.Errorf("clusterID must be set")
-		return "", "", err
+		return "", "", "", err
 	}
 
 	if err := validateNonEmptyField(clusterID, "clusterID"); err != nil {
-		return "", "", err
+		return "", "", "", err
 	}
 
 	monitors, err := util.Mons(csiConfigFile, clusterID)
 	if err != nil {
 		err = errors.Wrapf(err, "failed to fetch monitor list using clusterID (%s)", clusterID)
-		return "", "", err
+		return "", "", "", err
 	}
 
-	return monitors, clusterID, err
+	subvolumeGroup, err := util.CephFSSubvolumeGroup(csiConfigFile, clusterID)
+	if err != nil {
+		err = errors.Wrapf(err, "failed to fetch subvolumegroup using clusterID (%s)", clusterID)
+		return "", "", "", err
+	}
+
+	return clusterID, monitors, subvolumeGroup, err
 }
 
 // newVolumeOptions generates a new instance of volumeOptions from the provided
@@ -140,7 +147,7 @@ func newVolumeOptions(ctx context.Context, requestName string, req *csi.CreateVo
 
 	volOptions := req.GetParameters()
 
-	opts.Monitors, opts.ClusterID, err = getMonsAndClusterID(volOptions)
+	opts.ClusterID, opts.Monitors, opts.SubvolumeGroup, err = getClusterInformation(volOptions)
 	if err != nil {
 		return nil, err
 	}
@@ -225,6 +232,10 @@ func newVolumeOptionsFromVolID(ctx context.Context, volID string, volOpt, secret
 		return nil, nil, errors.Wrapf(err, "failed to fetch monitor list using clusterID (%s)", vi.ClusterID)
 	}
 
+	if volOptions.SubvolumeGroup, err = util.CephFSSubvolumeGroup(csiConfigFile, vi.ClusterID); err != nil {
+		return nil, nil, errors.Wrapf(err, "failed to fetch subvolumegroup list using clusterID (%s)", vi.ClusterID)
+	}
+
 	cr, err := util.NewAdminCredentials(secrets)
 	if err != nil {
 		return nil, nil, err
@@ -262,6 +273,10 @@ func newVolumeOptionsFromVolID(ctx context.Context, volID string, volOpt, secret
 			return nil, nil, err
 		}
 
+		if err = extractOptionalOption(&volOptions.SubvolumeGroup, "subvolumeGroup", volOpt); err != nil {
+			return nil, nil, err
+		}
+
 		if err = extractMounter(&volOptions.Mounter, volOpt); err != nil {
 			return nil, nil, err
 		}
@@ -358,7 +373,7 @@ func newVolumeOptionsFromStaticVolume(volID string, options map[string]string) (
 	// store NOT of static boolean
 	opts.ProvisionVolume = !staticVol
 
-	opts.Monitors, opts.ClusterID, err = getMonsAndClusterID(options)
+	opts.ClusterID, opts.Monitors, opts.SubvolumeGroup, err = getClusterInformation(options)
 	if err != nil {
 		return nil, nil, err
 	}

internal/util/csiconfig.go

@@ -23,53 +23,88 @@ import (
 	"strings"
 )
 
-// clusterInfo strongly typed JSON spec for the below JSON structure
+const (
+	// defaultCsiSubvolumeGroup defines the default name for the CephFS CSI subvolumegroup.
+	// This was hardcoded once and defaults to the old value to keep backward compatibility.
+	defaultCsiSubvolumeGroup = "csi"
+)
+
+// clusterInfo strongly typed JSON spec for the above JSON structure
 type clusterInfo struct {
 	// ClusterID is used for unique identification
 	ClusterID string `json:"clusterID"`
 	// Monitors is monitor list for corresponding cluster ID
 	Monitors []string `json:"monitors"`
+	// CephFS contains CephFS specific options
+	CephFS struct {
+		// SubvolumeGroup contains the name of the SubvolumeGroup for CSI volumes
+		SubvolumeGroup string `json:"subvolumeGroup"`
+	} `json:"cephFS"`
 }
 
-/*
-Mons returns a comma separated MON list from the csi config for the given clusterID
-Expected JSON structure in the passed in config file is,
-[
-	{
-		"clusterID": "<cluster-id>",
-		"monitors":
-			[
-				"<monitor-value>",
-				"<monitor-value>",
-				...
-			]
-	},
-	...
-]
-*/
-func Mons(pathToConfig, clusterID string) (string, error) {
+// Expected JSON structure in the passed in config file is,
+// [
+// 	{
+// 		"clusterID": "<cluster-id>",
+// 		"monitors":
+// 			[
+// 				"<monitor-value>",
+// 				"<monitor-value>",
+// 				...
+// 			],
+//         "cephFS": {
+//           "subvolumeGroup": "<subvolumegroup for cephfs volumes>"
+//         }
+// 	},
+// 	...
+// ]
+func readClusterInfo(pathToConfig, clusterID string) (clusterInfo, error) {
 	var config []clusterInfo
 
 	// #nosec
 	content, err := ioutil.ReadFile(pathToConfig)
 	if err != nil {
 		err = fmt.Errorf("error fetching configuration for cluster ID (%s). (%s)", clusterID, err)
-		return "", err
+		return clusterInfo{}, err
 	}
 
 	err = json.Unmarshal(content, &config)
 	if err != nil {
-		return "", fmt.Errorf("unmarshal failed: %v. raw buffer response: %s",
+		return clusterInfo{}, fmt.Errorf("unmarshal failed: %v. raw buffer response: %s",
 			err, string(content))
 	}
 
 	for _, cluster := range config {
 		if cluster.ClusterID == clusterID {
+			return cluster, nil
+		}
+	}
+
+	return clusterInfo{}, fmt.Errorf("missing configuration for cluster ID (%s)", clusterID)
+}
+
+// Mons returns a comma separated MON list from the csi config for the given clusterID
+func Mons(pathToConfig, clusterID string) (string, error) {
+	cluster, err := readClusterInfo(pathToConfig, clusterID)
+	if err != nil {
+		return "", err
+	}
+
 	if len(cluster.Monitors) == 0 {
 		return "", fmt.Errorf("empty monitor list for cluster ID (%s) in config", clusterID)
 	}
 	return strings.Join(cluster.Monitors, ","), nil
 }
+
+// CephFSSubvolumeGroup returns the subvolumeGroup for CephFS volumes. If not set, it returns the default value "csi"
+func CephFSSubvolumeGroup(pathToConfig, clusterID string) (string, error) {
+	cluster, err := readClusterInfo(pathToConfig, clusterID)
+	if err != nil {
+		return "", err
 	}
-	return "", fmt.Errorf("missing configuration for cluster ID (%s)", clusterID)
+
+	if cluster.CephFS.SubvolumeGroup == "" {
+		return defaultCsiSubvolumeGroup, nil
+	}
+	return cluster.CephFS.SubvolumeGroup, nil
 }