support configurable cache directory

fix https://github.com/seaweedfs/seaweedfs-csi-driver/issues/20

cmd/seaweedfs-csi-driver/main.go

@@ -17,6 +17,7 @@ var (
 	version           = flag.Bool("version", false, "Print the version and exit.")
 	concurrentWriters = flag.Int("concurrentWriters", 32, "limit concurrent goroutine writers if not 0")
 	cacheSizeMB       = flag.Int64("cacheCapacityMB", 1000, "local file chunk cache capacity in MB (0 will disable cache)")
+	cacheDir          = flag.String("cacheDir", os.TempDir(), "local cache directory for file chunks and meta data")
 )
 
 func main() {
@@ -37,5 +38,6 @@ func main() {
 	drv := driver.NewSeaweedFsDriver(*filer, *nodeID, *endpoint)
 	drv.ConcurrentWriters = *concurrentWriters
 	drv.CacheSizeMB = *cacheSizeMB
+	drv.CacheDir = *cacheDir
 	drv.Run()
 }

deploy/kubernetes/seaweedfs-csi.yaml

@@ -298,6 +298,7 @@ spec:
             - "--filer=$(SEAWEEDFS_FILER)"
             - "--nodeid=$(NODE_ID)"
             - "--cacheCapacityMB=$(SEAWEEDFS_CACHE_CAPACITY_MB)"
+            - "--cacheDir=$(SEAWEEDFS_CACHE_DIR)"
           env:
             - name: CSI_ENDPOINT
               value: unix:///var/lib/csi/sockets/pluginproxy/csi.sock
@@ -309,6 +310,8 @@ spec:
                   fieldPath: spec.nodeName
             - name: SEAWEEDFS_CACHE_CAPACITY_MB
               value: "1000"
+            - name: SEAWEEDFS_CACHE_DIR
+              value: /tmp
           imagePullPolicy: "Always"
           volumeMounts:
             - name: socket-dir
@@ -369,6 +372,7 @@ spec:
             - "--filer=$(SEAWEEDFS_FILER)"
             - "--nodeid=$(NODE_ID)"
             - "--cacheCapacityMB=$(SEAWEEDFS_CACHE_CAPACITY_MB)"
+            - "--cacheDir=$(SEAWEEDFS_CACHE_DIR)"
           env:
             - name: CSI_ENDPOINT
               value: unix:///csi/csi.sock
@@ -380,6 +384,8 @@ spec:
                   fieldPath: spec.nodeName
             - name: SEAWEEDFS_CACHE_CAPACITY_MB
               value: "1000"
+            - name: SEAWEEDFS_CACHE_DIR
+              value: /tmp
           imagePullPolicy: "IfNotPresent"
           volumeMounts:
             - name: plugin-dir

pkg/driver/driver.go

@@ -39,6 +39,7 @@ type SeaweedFsDriver struct {
 	grpcDialOption    grpc.DialOption
 	ConcurrentWriters int
 	CacheSizeMB       int64
+	CacheDir          string
 }
 
 func NewSeaweedFsDriver(filer, nodeID, endpoint string) *SeaweedFsDriver {

pkg/driver/mounter_seaweedfs.go

@@ -51,6 +51,9 @@ func (seaweedFs *seaweedFsMounter) Mount(target string) error {
 	if seaweedFs.driver.ConcurrentWriters > 0 {
 		args = append(args, fmt.Sprintf("-concurrentWriters=%d", seaweedFs.driver.ConcurrentWriters))
 	}
+	if seaweedFs.driver.CacheDir != "" {
+		args = append(args, fmt.Sprintf("-cacheDir=%s", seaweedFs.driver.CacheDir))
+	}
 	err := fuseMount(target, seaweedFsCmd, args)
 	if err != nil {
 		glog.Errorf("mount %s %s to %s: %s", seaweedFs.driver.filer, seaweedFs.bucketName, target, err)