Support for the ONTAP volume "-is-preserve-unlink-enabled" flag with the ontap-nas backend

frontend/common/volumes.go

@@ -138,6 +138,17 @@ func GetVolumeConfig(
 		snapshotDir = snapDirFormatted
 	}
 
+	// If preserveUnlink is provided, ensure it is lower case
+	preserveUnlink := collection.GetV(opts, "preserveUnlink", "")
+	if preserveUnlink != "" {
+		preserveUnlinkFormatted, err := convert.ToFormattedBool(preserveUnlink)
+		if err != nil {
+			Logc(ctx).WithError(err).Errorf("Invalid boolean value for preserveUnlink: %v.", preserveUnlink)
+			return nil, err
+		}
+		preserveUnlink = preserveUnlinkFormatted
+	}
+
 	cfg := &storage.VolumeConfig{
 		Name:                name,
 		Size:                fmt.Sprintf("%d", sizeBytes),
@@ -150,6 +161,7 @@ func GetVolumeConfig(
 		SplitOnClone:        collection.GetV(opts, "splitOnClone", ""),
 		SnapshotPolicy:      collection.GetV(opts, "snapshotPolicy", ""),
 		SnapshotReserve:     collection.GetV(opts, "snapshotReserve", ""),
+		PreserveUnlink:      preserveUnlink,
 		SnapshotDir:         snapshotDir,
 		ExportPolicy:        collection.GetV(opts, "exportPolicy", ""),
 		UnixPermissions:     collection.GetV(opts, "unixPermissions", ""),

frontend/csi/controller_helpers/kubernetes/config.go

@@ -49,6 +49,7 @@ const (
 	AnnSnapshotPolicy           = prefix + "/snapshotPolicy"
 	AnnSnapshotReserve          = prefix + "/snapshotReserve"
 	AnnSnapshotDir              = prefix + "/snapshotDirectory"
+	AnnPreserveUnlink           = prefix + "/preserveUnlink"
 	AnnUnixPermissions          = prefix + "/unixPermissions"
 	AnnExportPolicy             = prefix + "/exportPolicy"
 	AnnBlockSize                = prefix + "/blockSize"

frontend/csi/controller_helpers/kubernetes/helper.go

@@ -841,6 +841,16 @@ func getVolumeConfig(
 		snapshotDirAnn = snapDirFormatted
 	}
 
+	// If preserveUnlink annotation is provided, ensure it is lower case
+	preserveUnlinkAnn := getAnnotation(annotations, AnnPreserveUnlink)
+	if preserveUnlinkAnn != "" {
+		preserveUnlinkFormatted, err := convert.ToFormattedBool(preserveUnlinkAnn)
+		if err != nil {
+			Logc(ctx).WithError(err).Errorf("Invalid boolean value for preserveUnlink annotation: %v.", preserveUnlinkAnn)
+		}
+		preserveUnlinkAnn = preserveUnlinkFormatted
+	}
+
 	if getAnnotation(annotations, AnnReadOnlyClone) == "" {
 		annotations[AnnReadOnlyClone] = "false"
 	}
@@ -886,6 +896,7 @@ func getVolumeConfig(
 		SnapshotPolicy:      getAnnotation(annotations, AnnSnapshotPolicy),
 		SnapshotReserve:     getAnnotation(annotations, AnnSnapshotReserve),
 		SnapshotDir:         snapshotDirAnn,
+		PreserveUnlink:      preserveUnlinkAnn,
 		ExportPolicy:        getAnnotation(annotations, AnnExportPolicy),
 		UnixPermissions:     getAnnotation(annotations, AnnUnixPermissions),
 		StorageClass:        storageClass.Name,

storage/volume.go

@@ -24,6 +24,7 @@ type VolumeConfig struct {
 	SecurityStyle               string                  `json:"securityStyle"`
 	SnapshotPolicy              string                  `json:"snapshotPolicy,omitempty"`
 	SnapshotReserve             string                  `json:"snapshotReserve,omitempty"`
+	PreserveUnlink              string                  `json:"preserveUnlink,omitempty"`
 	SnapshotDir                 string                  `json:"snapshotDirectory,omitempty"`
 	ExportPolicy                string                  `json:"exportPolicy,omitempty"`
 	UnixPermissions             string                  `json:"unixPermissions,omitempty"`

storage_drivers/ontap/api/abstraction.go

@@ -233,6 +233,7 @@ type OntapAPI interface {
 	) (string, error)
 	VolumeRecoveryQueuePurge(ctx context.Context, recoveryQueueVolumeName string) error
 	VolumeRecoveryQueueGetName(ctx context.Context, name string) (string, error)
+	PreserveUnlinkSet(ctx context.Context, volumeName string) error
 	SMBShareCreate(ctx context.Context, shareName, path string) error
 	SMBShareExists(ctx context.Context, shareName string) (bool, error)
 	SMBShareDestroy(ctx context.Context, shareName string) error

storage_drivers/ontap/api/abstraction_rest.go

@@ -220,6 +220,14 @@ func (d OntapAPIREST) VolumeRecoveryQueueGetName(ctx context.Context, name strin
 	return recoveryQueueVolumeName, nil
 }
 
+func (d OntapAPIREST) PreserveUnlinkSet(ctx context.Context, volumeName string) error {
+	preserveUnlinkErr := d.api.PreserveUnlinkSet(ctx, volumeName)
+	if preserveUnlinkErr != nil {
+		return fmt.Errorf("error setting preserveUnlink %v: %v", volumeName, preserveUnlinkErr)
+	}
+	return nil
+}
+
 func (d OntapAPIREST) VolumeInfo(ctx context.Context, name string) (*Volume, error) {
 	fields := []string{
 		"type", "size", "comment", "aggregates", "nas", "guarantee",

storage_drivers/ontap/api/abstraction_zapi.go

@@ -125,6 +125,12 @@ func (d OntapAPIZAPI) VolumeDestroy(ctx context.Context, name string, force, ski
 	return nil
 }
 
+// The -is-preserve-unlink-enabled flag is only supported with newer ONTAP versions that use REST.
+func (d OntapAPIZAPI) PreserveUnlinkSet(ctx context.Context, volumeName string) error {
+	Logc(ctx).WithField("volume", volumeName).Warn("preserveUnlink cannot be set with ZAPI.")
+	return nil
+}
+
 func (d OntapAPIZAPI) VolumeRecoveryQueuePurge(ctx context.Context, recoveryQueueVolumeName string) error {
 	volRecoveryQueuePurgeResponse, err := d.api.VolumeRecoveryQueuePurge(recoveryQueueVolumeName)
 	if err != nil {

storage_drivers/ontap/api/ontap_rest.go

@@ -1770,6 +1770,67 @@ func (c *RestClient) VolumeRecoveryQueueGetName(ctx context.Context, name string
 	return responseObject.Records[0].Volume, nil
 }
 
+// PreserveUnlinkSet uses the cli passthrough REST API to set the is-preserve-unlink-enabled option on a volume.
+// This volume option was introduced in 9.12.1 but not made visible via the /storage/volumes REST API endpoint.
+func (c *RestClient) PreserveUnlinkSet(ctx context.Context, volumeName string) error {
+	fields := LogFields{
+		"Method":     "PreserveUnlinkSet",
+		"Type":       "ontap_rest",
+		"volumeName": volumeName,
+		"vserver":    c.svmName,
+	}
+	Logd(ctx, c.driverName, c.config.DebugTraceFlags["method"]).WithFields(fields).
+		Trace(">>>> PreserveUnlinkSet")
+	defer Logd(ctx, c.driverName, c.config.DebugTraceFlags["method"]).WithFields(fields).
+		Trace("<<<< PrserveUnlinkSet")
+
+	requestUrl := fmt.Sprintf("https://%s/api/private/cli/volume?vserver=%s&volume=%s",
+		c.config.ManagementLIF, c.svmName, volumeName)
+
+	requestContent := map[string]string{
+		"is-preserve-unlink-enabled": "true",
+	}
+	requestBodyBytes, err := json.Marshal(requestContent)
+	if err != nil {
+		return err
+	}
+
+	request, err := http.NewRequestWithContext(ctx, http.MethodPatch, requestUrl, bytes.NewReader(requestBodyBytes))
+	if err != nil {
+		return err
+	}
+
+	response, err := c.sendPassThroughCliCommand(ctx, request)
+	if err != nil {
+		return err
+	}
+
+	defer func() { _ = response.Body.Close() }()
+
+	var responseBodyBytes []byte
+	var responseBodyString string
+	if response.Body != nil {
+		responseBodyBytes, _ = io.ReadAll(response.Body)
+		responseBodyString = string(responseBodyBytes)
+	} else {
+		Logc(ctx).WithField("statusCode", response.StatusCode).Error(
+			"no response when trying to set preserveUnlink.")
+		return fmt.Errorf("no response with status code: %v", response.StatusCode)
+	}
+	if response.StatusCode != http.StatusOK {
+		Logc(ctx).WithField("statusCode", response.StatusCode).Error(
+			"failed to set preserveUnlink: %s", responseBodyString)
+		return fmt.Errorf("unexpected response status code: %v", response.StatusCode)
+	}
+	if !strings.Contains(responseBodyString, "modify successful") {
+		Logc(ctx).WithField("statusCode", response.StatusCode).Error(
+			"unexpected response when setting preserveUnlink: %s", responseBodyString)
+		return fmt.Errorf("unexpected response boday with status code: %v", response.StatusCode)
+	}
+
+	return nil
+}
+
 func (c *RestClient) sendPassThroughCliCommand(ctx context.Context, request *http.Request) (*http.Response, error) {
 	request.Header.Set("Content-Type", "application/json")
 

storage_drivers/ontap/api/types.go

@@ -20,6 +20,7 @@ type Volume struct {
 	SnapshotDir       *bool
 	SnapshotPolicy    string
 	SnapshotReserve   int
+	PreserveUnlink    *bool
 	SnapshotSpaceUsed int
 	SpaceReserve      string
 	TieringPolicy     string

storage_drivers/ontap/ontap_common.go

@@ -92,6 +92,7 @@ const (
 	SpaceReserve          = "spaceReserve"
 	SnapshotPolicy        = "snapshotPolicy"
 	SnapshotReserve       = "snapshotReserve"
+	PreserveUnlink        = "preserveUnlink"
 	UnixPermissions       = "unixPermissions"
 	ExportPolicy          = "exportPolicy"
 	SecurityStyle         = "securityStyle"
@@ -1748,6 +1749,7 @@ const (
 	DefaultSpaceReserve              = "none"
 	DefaultSnapshotPolicy            = "none"
 	DefaultSnapshotReserve           = "5"
+	DefaultPreserveUnlink            = "false"
 	DefaultUnixPermissions           = "---rwxrwxrwx"
 	DefaultSnapshotDir               = "false"
 	DefaultExportPolicy              = "default"
@@ -1812,6 +1814,10 @@ func PopulateConfigurationDefaults(ctx context.Context, config *drivers.OntapSto
 		}
 	}
 
+	if config.PreserveUnlink == "" {
+		config.PreserveUnlink = DefaultPreserveUnlink
+	}
+
 	// If snapshotDir is provided, ensure it is lower case
 	snapDir := DefaultSnapshotDir
 	if config.SnapshotDir != "" {
@@ -1822,6 +1828,16 @@ func PopulateConfigurationDefaults(ctx context.Context, config *drivers.OntapSto
 	}
 	config.SnapshotDir = snapDir
 
+	// If preserveUnlink is provided, ensure it is lower case
+	preserveUnlink := DefaultPreserveUnlink
+	if config.PreserveUnlink != "" {
+		if preserveUnlink, err = convert.ToFormattedBool(config.PreserveUnlink); err != nil {
+			Logc(ctx).WithError(err).Errorf("Invalid boolean value for preserveUnlink: %v.", config.PreserveUnlink)
+			return fmt.Errorf("invalid boolean value for preserveUnlink: %v", err)
+		}
+	}
+	config.PreserveUnlink = preserveUnlink
+
 	if config.DenyNewVolumePools == "" {
 		config.DenyNewVolumePools = DefaultDenyNewVolumePools
 	} else {
@@ -1950,6 +1966,7 @@ func PopulateConfigurationDefaults(ctx context.Context, config *drivers.OntapSto
 		"SpaceReserve":           config.SpaceReserve,
 		"SnapshotPolicy":         config.SnapshotPolicy,
 		"SnapshotReserve":        config.SnapshotReserve,
+		"PreserveUnlink":         config.PreserveUnlink,
 		"UnixPermissions":        config.UnixPermissions,
 		"SnapshotDir":            config.SnapshotDir,
 		"ExportPolicy":           config.ExportPolicy,
@@ -2615,6 +2632,10 @@ func getVolumeExternalCommon(
 	if volume.SnapshotDir != nil {
 		snapshotDir = *volume.SnapshotDir
 	}
+	preserveUnlink := false
+	if volume.PreserveUnlink != nil {
+		preserveUnlink = *volume.PreserveUnlink
+	}
 	volumeConfig := &storage.VolumeConfig{
 		Version:         tridentconfig.OrchestratorAPIVersion,
 		Name:            name,
@@ -2625,6 +2646,7 @@ func getVolumeExternalCommon(
 		SnapshotReserve: strconv.Itoa(volume.SnapshotReserve),
 		ExportPolicy:    volume.ExportPolicy,
 		SnapshotDir:     strconv.FormatBool(snapshotDir),
+		PreserveUnlink:  strconv.FormatBool(preserveUnlink),
 		UnixPermissions: volume.UnixPermissions,
 		StorageClass:    "",
 		AccessMode:      tridentconfig.ReadWriteMany,
@@ -2901,6 +2923,7 @@ func setStoragePoolAttributes(
 	pool.InternalAttributes()[SpaceReserve] = config.SpaceReserve
 	pool.InternalAttributes()[SnapshotPolicy] = config.SnapshotPolicy
 	pool.InternalAttributes()[SnapshotReserve] = config.SnapshotReserve
+	pool.InternalAttributes()[PreserveUnlink] = config.PreserveUnlink
 	pool.InternalAttributes()[SplitOnClone] = config.SplitOnClone
 	pool.InternalAttributes()[Encryption] = config.Encryption
 	pool.InternalAttributes()[LUKSEncryption] = config.LUKSEncryption
@@ -3023,6 +3046,11 @@ func initializeVirtualPools(
 			snapshotReserve = vpool.SnapshotReserve
 		}
 
+		preserveUnlink := config.PreserveUnlink
+		if vpool.PreserveUnlink != "" {
+			preserveUnlink = vpool.PreserveUnlink
+		}
+
 		splitOnClone := config.SplitOnClone
 		if vpool.SplitOnClone != "" {
 			splitOnClone = vpool.SplitOnClone
@@ -3155,6 +3183,7 @@ func initializeVirtualPools(
 		pool.InternalAttributes()[SpaceReserve] = spaceReserve
 		pool.InternalAttributes()[SnapshotPolicy] = snapshotPolicy
 		pool.InternalAttributes()[SnapshotReserve] = snapshotReserve
+		pool.InternalAttributes()[PreserveUnlink] = preserveUnlink
 		pool.InternalAttributes()[SplitOnClone] = splitOnClone
 		pool.InternalAttributes()[UnixPermissions] = unixPermissions
 		pool.InternalAttributes()[SnapshotDir] = snapshotDir
@@ -3696,6 +3725,16 @@ func getVolumeOptsCommon(
 		opts["snapshotDir"] = snapshotDirFormatted
 	}
 
+	// If preserveUnlink is provided, ensure it is lower case
+	if volConfig.PreserveUnlink != "" {
+		preserveUnlinkFormatted, err := convert.ToFormattedBool(volConfig.PreserveUnlink)
+		if err != nil {
+			Logc(ctx).WithError(err).Errorf(
+				"Invalid boolean value for volume '%v' preserveUnlink: %v.", volConfig.Name, volConfig.PreserveUnlink)
+		}
+		opts["preserveUnlink"] = preserveUnlinkFormatted
+	}
+
 	// If skipRecoveryQueue is provided, ensure it is lower case
 	if volConfig.SkipRecoveryQueue != "" {
 		skipRecoveryQueueFormatted, err := convert.ToFormattedBool(volConfig.SkipRecoveryQueue)
@@ -5474,6 +5513,14 @@ func purgeRecoveryQueueVolume(ctx context.Context, api api.OntapAPI, volumeName
 	}
 }
 
+// setPreserveUnlink has to be handled specially
+func setPresrveUnlink(ctx context.Context, api api.OntapAPI, volumeName string) {
+	if err := api.PreserveUnlinkSet(ctx, volumeName); err != nil {
+		Logc(ctx).WithField("volume",
+			volumeName).Errorf("error setting preserveUnlink: %v", err)
+	}
+}
+
 // getSMBShareNamePath constructs the SMB share name and path based on the provided parameters.
 func getSMBShareNamePath(flexvol, name string, secureSMBEnabled bool) (string, string) {
 	if secureSMBEnabled {

storage_drivers/ontap/ontap_nas.go

@@ -269,6 +269,7 @@ func (d *NASStorageDriver) Create(
 		spaceReserve      = collection.GetV(opts, "spaceReserve", storagePool.InternalAttributes()[SpaceReserve])
 		snapshotPolicy    = collection.GetV(opts, "snapshotPolicy", storagePool.InternalAttributes()[SnapshotPolicy])
 		snapshotReserve   = collection.GetV(opts, "snapshotReserve", storagePool.InternalAttributes()[SnapshotReserve])
+		preserveUnlink    = collection.GetV(opts, "preserveUnlink", storagePool.InternalAttributes()[PreserveUnlink])
 		unixPermissions   = collection.GetV(opts, "unixPermissions", storagePool.InternalAttributes()[UnixPermissions])
 		snapshotDir       = collection.GetV(opts, "snapshotDir", storagePool.InternalAttributes()[SnapshotDir])
 		exportPolicy      = collection.GetV(opts, "exportPolicy", storagePool.InternalAttributes()[ExportPolicy])
@@ -280,7 +281,7 @@ func (d *NASStorageDriver) Create(
 		qosPolicy         = storagePool.InternalAttributes()[QosPolicy]
 		adaptiveQosPolicy = storagePool.InternalAttributes()[AdaptiveQosPolicy]
 	)
-
+	
 	snapshotReserveInt, err := GetSnapshotReserve(snapshotPolicy, snapshotReserve)
 	if err != nil {
 		return fmt.Errorf("invalid value for snapshotReserve: %v", err)
@@ -313,6 +314,11 @@ func (d *NASStorageDriver) Create(
 		return fmt.Errorf("invalid boolean value for snapshotDir: %v", err)
 	}
 
+	enablePreserveUnlink, err := strconv.ParseBool(preserveUnlink)
+	if err != nil {
+		return fmt.Errorf("invalid boolean value for preserveUnlink: %v", err)
+	}
+
 	enableEncryption, configEncryption, err := GetEncryptionValue(encryption)
 	if err != nil {
 		return fmt.Errorf("invalid boolean value for encryption: %v", err)
@@ -355,6 +361,7 @@ func (d *NASStorageDriver) Create(
 	volConfig.SpaceReserve = spaceReserve
 	volConfig.SnapshotPolicy = snapshotPolicy
 	volConfig.SnapshotReserve = snapshotReserve
+	volConfig.PreserveUnlink = preserveUnlink
 	volConfig.UnixPermissions = unixPermissions
 	volConfig.SnapshotDir = snapshotDir
 	volConfig.ExportPolicy = exportPolicy
@@ -370,6 +377,7 @@ func (d *NASStorageDriver) Create(
 		"spaceReserve":      spaceReserve,
 		"snapshotPolicy":    snapshotPolicy,
 		"snapshotReserve":   snapshotReserveInt,
+		"preserveUnlink":    enablePreserveUnlink,
 		"unixPermissions":   unixPermissions,
 		"snapshotDir":       enableSnapshotDir,
 		"exportPolicy":      exportPolicy,
@@ -463,6 +471,11 @@ func (d *NASStorageDriver) Create(
 			}
 		}
 
+		// Set is-unlink-preserve-enabled if required
+		if enablePreserveUnlink {
+			setPresrveUnlink(ctx, d.API, volConfig.InternalName)
+		}
+
 		return nil
 	}
 

storage_drivers/types.go

@@ -198,6 +198,7 @@ type OntapStorageDriverConfigDefaults struct {
 	SpaceReserve      string `json:"spaceReserve"`
 	SnapshotPolicy    string `json:"snapshotPolicy"`
 	SnapshotReserve   string `json:"snapshotReserve"`
+	PreserveUnlink    string `json:"preserveUnlink"`
 	SnapshotDir       string `json:"snapshotDir"`
 	UnixPermissions   string `json:"unixPermissions"`
 	ExportPolicy      string `json:"exportPolicy"`