Add support for NVMe disk types by using deviceutils

Change volumes map to use symlink as key and add volumeID and real
path to the deviceMappings object, this is because there can be
multiple symlinks per volume

Filter out caching and logging info on non pd/hyperdisk volumes

Failure to get real path at add volume time is no longer an error
the real path may be unavailable at this time

Author: cemakd

cmd/gce-pd-csi-driver/main.go

@@ -98,6 +98,8 @@ var (
 
 	diskTopology = flag.Bool("disk-topology", false, "If set to true, the driver will add a disk-type.gke.io/[disk-type] topology label when the StorageClass has the use-allowed-disk-topology parameter set to true. That topology label is included in the Topologies returned in CreateVolumeResponse. This flag is disabled by default.")
 
+	diskCacheSyncPeriod = flag.Duration("disk-cache-sync-period", 10*time.Minute, "Period for the disk cache to check the /dev/disk/by-id/ directory and evaluate the symlinks")
+
 	version string
 )
 
@@ -276,7 +278,7 @@ func handle() {
 			klog.Fatalf("Failed to get node info from API server: %v", err.Error())
 		}
 
-		deviceCache, err := linkcache.NewDeviceCacheForNode(ctx, 1*time.Minute, *nodeName)
+		deviceCache, err := linkcache.NewDeviceCacheForNode(ctx, *diskCacheSyncPeriod, *nodeName, driverName, deviceUtils)
 		if err != nil {
 			klog.Warningf("Failed to create device cache: %v", err.Error())
 		} else {

pkg/gce-pd-csi-driver/node_test.go

@@ -46,7 +46,7 @@ const (
 
 func getTestGCEDriver(t *testing.T) *GCEDriver {
 	return getCustomTestGCEDriver(t, mountmanager.NewFakeSafeMounter(), deviceutils.NewFakeDeviceUtils(false), metadataservice.NewFakeService(), &NodeServerArgs{
-		DeviceCache: linkcache.TestDeviceCache(1*time.Minute, linkcache.TestNodeWithVolumes([]string{defaultVolumeID})),
+		DeviceCache: linkcache.NewTestDeviceCache(1*time.Minute, linkcache.NewTestNodeWithVolumes([]string{defaultVolumeID})),
 	})
 }
 
@@ -192,7 +192,7 @@ func TestNodeGetVolumeStats(t *testing.T) {
 
 			mounter := mountmanager.NewFakeSafeMounterWithCustomExec(&testingexec.FakeExec{CommandScript: actionList})
 			gceDriver := getTestGCEDriverWithCustomMounter(t, mounter, &NodeServerArgs{
-				DeviceCache: linkcache.TestDeviceCache(1*time.Minute, linkcache.TestNodeWithVolumes([]string{tc.volumeID})),
+				DeviceCache: linkcache.NewTestDeviceCache(1*time.Minute, linkcache.NewTestNodeWithVolumes([]string{tc.volumeID})),
 			})
 			ns := gceDriver.ns
 
@@ -1233,7 +1233,7 @@ func TestNodeStageVolume(t *testing.T) {
 			}
 			mounter := mountmanager.NewFakeSafeMounterWithCustomExec(&testingexec.FakeExec{CommandScript: actionList, ExactOrder: true})
 			gceDriver := getTestGCEDriverWithCustomMounter(t, mounter, &NodeServerArgs{
-				DeviceCache: linkcache.TestDeviceCache(1*time.Minute, linkcache.TestNodeWithVolumes([]string{volumeID})),
+				DeviceCache: linkcache.NewTestDeviceCache(1*time.Minute, linkcache.NewTestNodeWithVolumes([]string{volumeID})),
 			})
 			ns := gceDriver.ns
 			ns.SysfsPath = tempDir + "/sys"

pkg/linkcache/devices_linux.go

@@ -10,25 +10,26 @@ import (
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/klog/v2"
 	"sigs.k8s.io/gcp-compute-persistent-disk-csi-driver/pkg/common"
+	"sigs.k8s.io/gcp-compute-persistent-disk-csi-driver/pkg/deviceutils"
 	"sigs.k8s.io/gcp-compute-persistent-disk-csi-driver/pkg/k8sclient"
 )
 
 const byIdDir = "/dev/disk/by-id"
 
-func NewDeviceCacheForNode(ctx context.Context, period time.Duration, nodeName string) (*DeviceCache, error) {
+func NewDeviceCacheForNode(ctx context.Context, period time.Duration, nodeName string, driverName string, deviceUtils deviceutils.DeviceUtils) (*DeviceCache, error) {
 	node, err := k8sclient.GetNodeWithRetry(ctx, nodeName)
 	if err != nil {
 		return nil, fmt.Errorf("failed to get node %s: %w", nodeName, err)
 	}
 
-	return newDeviceCacheForNode(period, node), nil
+	return newDeviceCacheForNode(period, node, driverName, deviceUtils), nil
 }
 
-func TestDeviceCache(period time.Duration, node *v1.Node) *DeviceCache {
-	return newDeviceCacheForNode(period, node)
+func NewTestDeviceCache(period time.Duration, node *v1.Node) *DeviceCache {
+	return newDeviceCacheForNode(period, node, "pd.csi.storage.gke.io", deviceutils.NewDeviceUtils())
 }
 
-func TestNodeWithVolumes(volumes []string) *v1.Node {
+func NewTestNodeWithVolumes(volumes []string) *v1.Node {
 	volumesInUse := make([]v1.UniqueVolumeName, len(volumes))
 	for i, volume := range volumes {
 		volumesInUse[i] = v1.UniqueVolumeName("kubernetes.io/csi/pd.csi.storage.gke.io^" + volume)
@@ -41,36 +42,37 @@ func TestNodeWithVolumes(volumes []string) *v1.Node {
 	}
 }
 
-func newDeviceCacheForNode(period time.Duration, node *v1.Node) *DeviceCache {
+func newDeviceCacheForNode(period time.Duration, node *v1.Node, driverName string, deviceUtils deviceutils.DeviceUtils) *DeviceCache {
 	deviceCache := &DeviceCache{
-		volumes: make(map[string]deviceMapping),
-		period:  period,
-		dir:     byIdDir,
+		symlinks:    make(map[string]deviceMapping),
+		period:      period,
+		deviceUtils: deviceUtils,
+		dir:         byIdDir,
 	}
 
 	// Look at the status.volumesInUse field.  For each, take the last section
 	// of the string (after the last "/") and call AddVolume for that
 	for _, volume := range node.Status.VolumesInUse {
-		klog.Infof("Adding volume %s to cache", string(volume))
-		vID, err := pvNameFromVolumeID(string(volume))
-		if err != nil {
-			klog.Warningf("failure to retrieve name, skipping volume %q: %v", string(volume), err)
+		volumeName := string(volume)
+		tokens := strings.Split(volumeName, "^")
+		if len(tokens) != 2 {
+			klog.V(5).Infof("Skipping volume %q because splitting volumeName on `^` returns %d tokens, expected 2", volumeName, len(tokens))
+			continue
+		}
+
+		// The first token is of the form "kubernetes.io/csi/<driver-name>" or just "<driver-name>".
+		// We should check if it contains the driver name we are interested in.
+		if !strings.Contains(tokens[0], driverName) {
+			klog.V(5).Infof("Skipping volume %q because it is not a %s volume.", volumeName, driverName)
 			continue
 		}
-		deviceCache.AddVolume(vID)
+		klog.Infof("Adding volume %s to cache", string(volume))
+		deviceCache.AddVolume(tokens[1])
 	}
 
 	return deviceCache
 }
 
-func pvNameFromVolumeID(volumeID string) (string, error) {
-	tokens := strings.Split(volumeID, "^")
-	if len(tokens) != 2 {
-		return "", fmt.Errorf("invalid volume ID, split on `^` returns %d tokens, expected 2", len(tokens))
-	}
-	return tokens[1], nil
-}
-
 // Run since it needs an infinite loop to keep itself up to date
 func (d *DeviceCache) Run(ctx context.Context) {
 	klog.Infof("Starting device cache watcher for directory %s with period %s", d.dir, d.period)
@@ -87,7 +89,7 @@ func (d *DeviceCache) Run(ctx context.Context) {
 		case <-ticker.C:
 			d.listAndUpdate()
 
-			klog.Infof("Cache contents: %+v", d.volumes)
+			klog.Infof("Cache contents: %+v", d.symlinks)
 		}
 	}
 }
@@ -106,21 +108,32 @@ func (d *DeviceCache) AddVolume(volumeID string) error {
 		return fmt.Errorf("error getting device name: %w", err)
 	}
 
-	// Look at the dir for a symlink that matches the pvName
-	symlink := filepath.Join(d.dir, "google-"+deviceName)
-	klog.Infof("Looking for symlink %s", symlink)
-
-	realPath, err := filepath.EvalSymlinks(symlink)
-	if err != nil {
-		klog.Warningf("Error evaluating symlink for volume %s: %v", volumeID, err)
-		return nil
+	symlinks := d.deviceUtils.GetDiskByIdPaths(deviceName, "")
+	if len(symlinks) == 0 {
+		return fmt.Errorf("no symlink paths found for volume %s", volumeID)
 	}
 
-	klog.Infof("Found real path %s for volume %s", realPath, volumeID)
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
 
-	d.volumes[volumeID] = deviceMapping{
-		symlink:  symlink,
-		realPath: realPath,
+	// We may have multiple symlinks for a given device, we should add all of them.
+	for _, symlink := range symlinks {
+		realPath, err := filepath.EvalSymlinks(symlink)
+		if err != nil {
+			// This is not an error, as the symlink may not have been created yet.
+			// Leave real_path empty; the periodic check will update it.
+			klog.V(5).Infof("Could not evaluate symlink %s, will retry: %v", symlink, err)
+			realPath = ""
+		} else {
+			klog.Infof("Found real path %s for volume %s", realPath, volumeID)
+		}
+		// The key is the symlink path. The value contains the evaluated
+		// real path and the original volumeID for better logging.
+		d.symlinks[symlink] = deviceMapping{
+			volumeID: volumeID,
+			realPath: realPath,
+		}
+		klog.V(4).Infof("Added volume %s to cache with symlink %s", volumeID, symlink)
 	}
 
 	return nil
@@ -129,25 +142,31 @@ func (d *DeviceCache) AddVolume(volumeID string) error {
 // Remove the volume from the cache.
 func (d *DeviceCache) RemoveVolume(volumeID string) {
 	klog.Infof("Removing volume %s from cache", volumeID)
-	delete(d.volumes, volumeID)
+	d.mutex.Lock()
+	defer d.mutex.Unlock()
+	for symlink, device := range d.symlinks {
+		if device.volumeID == volumeID {
+			delete(d.symlinks, symlink)
+		}
+	}
 }
 
 func (d *DeviceCache) listAndUpdate() {
-	for volumeID, device := range d.volumes {
+	for symlink, device := range d.symlinks {
 		// Evaluate the symlink
-		realPath, err := filepath.EvalSymlinks(device.symlink)
+		realPath, err := filepath.EvalSymlinks(symlink)
 		if err != nil {
-			klog.Warningf("Error evaluating symlink for volume %s: %v", volumeID, err)
+			klog.Warningf("Error evaluating symlink for volume %s: %v", device.volumeID, err)
 			continue
 		}
 
 		// Check if the realPath has changed
 		if realPath != device.realPath {
-			klog.Warningf("Change in device path for volume %s (symlink: %s), previous path: %s, new path: %s", volumeID, device.symlink, device.realPath, realPath)
+			klog.Warningf("Change in device path for volume %s (symlink: %s), previous path: %s, new path: %s", device.volumeID, symlink, device.realPath, realPath)
 
 			// Update the cache with the new realPath
 			device.realPath = realPath
-			d.volumes[volumeID] = device
+			d.symlinks[symlink] = device
 		}
 	}
 }

pkg/linkcache/types.go

@@ -1,15 +1,22 @@
 package linkcache
 
-import "time"
+import (
+	"sync"
+	"time"
+
+	"sigs.k8s.io/gcp-compute-persistent-disk-csi-driver/pkg/deviceutils"
+)
 
 type deviceMapping struct {
-	symlink  string
+	volumeID string
 	realPath string
 }
 
 type DeviceCache struct {
-	volumes map[string]deviceMapping
-	period  time.Duration
+	mutex    sync.Mutex
+	symlinks map[string]deviceMapping
+	period   time.Duration
 	// dir is the directory to look for device symlinks
-	dir string
+	dir         string
+	deviceUtils deviceutils.DeviceUtils
 }

test/sanity/sanity_test.go

@@ -78,7 +78,7 @@ func TestSanity(t *testing.T) {
 		EnableDeviceInUseCheck: true,
 		DeviceInUseTimeout:     0,
 		EnableDataCache:        enableDataCache,
-		DeviceCache:            linkcache.TestDeviceCache(1*time.Minute, linkcache.TestNodeWithVolumes([]string{})),
+		DeviceCache:            linkcache.NewTestDeviceCache(1*time.Minute, linkcache.NewTestNodeWithVolumes([]string{})),
 	}
 
 	// Initialize GCE Driver