ontap-nas-economy fixes for 17.10.1

Making qtree delete idempotent as needed by Trident
Allow deleting qtrees with really long names

CHANGELOG.md

@@ -2,7 +2,17 @@
 
 [Releases](https://github.com/NetApp/netappdvp/releases)
 
-## Changes since 17.07.0
+## Changes since 17.10.0
+
+**Fixes:**
+- Added delete idempotency to the ontap-nas-economy driver as needed by Trident.
+- Fixed an issue where qtrees with names near the 64-character limit could not
+  be deleted.
+
+**Enhancements:**
+
+
+## 17.10.0
 
 **Fixes:**
 - Changed the SolidFire driver to tear down the iSCSI connection as part

storage_drivers/ontap_nas_qtree.go

@@ -21,6 +21,7 @@ import (
 // OntapNASQtreeStorageDriverName is the constant name for this Ontap qtree-based NAS storage driver
 const OntapNASQtreeStorageDriverName = "ontap-nas-economy"
 const deletedQtreeNamePrefix = "deleted_"
+const maxQtreeNameLength = 64
 const maxQtreesPerFlexvol = 200
 const defaultPruneFlexvolsPeriodSecs = uint64(600) // default to 10 minutes
 const defaultResizeQuotasPeriodSecs = uint64(60)   // default to 1 minute
@@ -171,20 +172,20 @@ func (d *OntapNASQtreeStorageDriver) startHousekeepingTasks() {
 
 	// Keep the system devoid of Flexvols with no qtrees
 	d.pruneUnusedFlexvols()
+	d.reapDeletedQtrees()
 	pruneTicker := time.NewTicker(time.Duration(pruneFlexvolsPeriodSecs) * time.Second)
 	go func() {
-		for t := range pruneTicker.C {
-			log.WithField("tick", t).Debug("Running housekeeping task: prune unused Flexvols.")
+		for range pruneTicker.C {
 			d.pruneUnusedFlexvols()
+			d.reapDeletedQtrees()
 		}
 	}()
 
 	// Keep the quotas current
 	d.resizeQuotas()
 	resizeTicker := time.NewTicker(time.Duration(resizeQuotasPeriodSecs) * time.Second)
 	go func() {
-		for t := range resizeTicker.C {
-			log.WithField("tick", t).Debug("Running housekeeping task: resize quotas.")
+		for range resizeTicker.C {
 			d.resizeQuotas()
 		}
 	}()
@@ -219,6 +220,11 @@ func (d *OntapNASQtreeStorageDriver) Create(name string, sizeBytes uint64, opts
 		return fmt.Errorf("Volume %s already exists.", name)
 	}
 
+	// Ensure qtree name isn't too long
+	if len(name) > maxQtreeNameLength {
+		return fmt.Errorf("Volume %s name exceeds the limit of %d characters.", name, maxQtreeNameLength)
+	}
+
 	// Get Flexvol options with default fallback values
 	// see also: ontap_common.go#PopulateConfigurationDefaults
 	size := strconv.FormatUint(sizeBytes, 10)
@@ -336,11 +342,19 @@ func (d *OntapNASQtreeStorageDriver) Destroy(name string) error {
 	}
 	if !exists {
 		log.WithField("qtree", name).Warn("Qtree not found.")
+		return nil
 	}
 
-	// Rename qtree so it doesn't show up in lists while ONTAP is deleting it in the background
+	// Rename qtree so it doesn't show up in lists while ONTAP is deleting it in the background.
+	// Ensure the deleted name doesn't exceed the qtree name length limit of 64 characters.
 	path := fmt.Sprintf("/vol/%s/%s", flexvol, name)
-	deletedPath := fmt.Sprintf("/vol/%s/%s", flexvol, deletedQtreeNamePrefix+name+"_"+utils.RandomString(5))
+	deletedName := deletedQtreeNamePrefix + name + "_" + utils.RandomString(5)
+	if len(deletedName) > maxQtreeNameLength {
+		trimLength := len(deletedQtreeNamePrefix) + 10
+		deletedName = deletedQtreeNamePrefix + name[trimLength:] + "_" + utils.RandomString(5)
+	}
+	deletedPath := fmt.Sprintf("/vol/%s/%s", flexvol, deletedName)
+
 	renameResponse, err := d.API.QtreeRename(path, deletedPath)
 	if err = ontap.GetError(renameResponse, err); err != nil {
 		log.Errorf("Qtree rename failed. %v", err)
@@ -801,6 +815,8 @@ func (d *OntapNASQtreeStorageDriver) resizeQuotas() {
 	d.provMutex.Lock()
 	defer d.provMutex.Unlock()
 
+	log.Debug("Housekeeping, resizing quotas.")
+
 	for flexvol, resize := range d.quotaResizeMap {
 
 		if resize {
@@ -872,6 +888,8 @@ func (d *OntapNASQtreeStorageDriver) pruneUnusedFlexvols() {
 	d.provMutex.Lock()
 	defer d.provMutex.Unlock()
 
+	log.Debug("Housekeeping, checking for managed Flexvols with no qtrees.")
+
 	// Get list of Flexvols managed by this driver
 	volumeListResponse, err := d.API.VolumeList(d.FlexvolNamePrefix())
 	if err = ontap.GetError(volumeListResponse, err); err != nil {
@@ -885,8 +903,6 @@ func (d *OntapNASQtreeStorageDriver) pruneUnusedFlexvols() {
 		flexvols = append(flexvols, volName)
 	}
 
-	log.WithField("flexvols", len(flexvols)).Debug("Housekeeping, checking for managed Flexvols with qtrees.")
-
 	// Destroy any Flexvol if it is devoid of qtrees
 	for _, flexvol := range flexvols {
 		qtreeCount, err := d.API.QtreeCount(flexvol)
@@ -897,6 +913,30 @@ func (d *OntapNASQtreeStorageDriver) pruneUnusedFlexvols() {
 	}
 }
 
+// reapDeletedQtrees is called periodically by a background task.  Any qtrees
+// that have been deleted (discovered by virtue of having a well-known hardcoded
+// prefix on their names) are destroyed.  This is only needed for the exceptional case
+// in which a qtree was renamed (prior to being destroyed) but the subsequent
+// destroy call failed or was never made due to a process interruption.
+func (d *OntapNASQtreeStorageDriver) reapDeletedQtrees() {
+
+	log.Debug("Housekeeping, checking for deleted qtrees.")
+
+	// Get all deleted qtrees in all FlexVols managed by this driver
+	prefix := deletedQtreeNamePrefix + *d.Config.StoragePrefix
+	listResponse, err := d.API.QtreeList(prefix, d.FlexvolNamePrefix())
+	if err = ontap.GetError(listResponse, err); err != nil {
+		log.Errorf("Error listing deleted qtrees. %v", err)
+	}
+
+	// AttributesList() returns []QtreeInfoType
+	for _, qtree := range listResponse.Result.AttributesList() {
+		qtreePath := fmt.Sprintf("/vol/%s/%s", qtree.Volume(), qtree.Qtree())
+		log.WithField("qtree", qtreePath).Debug("Housekeeping, reaping deleted qtree.")
+		d.API.QtreeDestroyAsync(qtreePath, true)
+	}
+}
+
 // ensureDefaultExportPolicy checks for an export policy with a well-known name that will be suitable
 // for setting on a Flexvol and will enable access to all qtrees therein.  If the policy exists, the
 // method assumes it created the policy itself and that all is good.  If the policy does not exist,

storage_drivers/storage_drivers.go

@@ -24,7 +24,7 @@ const (
 const ConfigVersion = 1
 
 // DriverVersion is the actual release version number
-const DriverVersion = "17.10.0"
+const DriverVersion = "17.10.1"
 
 // FullDriverVersion is the DriverVersion as well as any pre-release tags
 var FullDriverVersion = DriverVersion