posix: Return errDiskNotWritable during disk initialization. (#2048)

It can happen that minio server might not have
writable permissions on the export paths command line.

Fixes #2035

fs-v1.go

@@ -85,8 +85,21 @@ func newFSObjects(disk string) (ObjectLayer, error) {
 		return nil, err
 	}
 
+	// Attempt to create `.minio`.
+	err = storage.MakeVol(minioMetaBucket)
+	if err != nil {
+		switch err {
+		// Ignore the errors.
+		case errVolumeExists, errDiskNotFound, errFaultyDisk:
+		default:
+			return nil, toObjectErr(err, minioMetaBucket)
+		}
+	}
+
 	// Runs house keeping code, like creating minioMetaBucket, cleaning up tmp files etc.
-	fsHouseKeeping(storage)
+	if err = fsHouseKeeping(storage); err != nil {
+		return nil, err
+	}
 
 	// loading format.json from minioMetaBucket.
 	// Note: The format.json content is ignored, reserved for future use.

object-common.go

@@ -45,17 +45,10 @@ func registerShutdown(callback func()) {
 
 // House keeping code needed for FS.
 func fsHouseKeeping(storageDisk StorageAPI) error {
-	// Attempt to create `.minio`.
-	err := storageDisk.MakeVol(minioMetaBucket)
-	if err != nil {
-		if err != errVolumeExists && err != errDiskNotFound && err != errFaultyDisk {
-			return err
-		}
-	}
 	// Cleanup all temp entries upon start.
-	err = cleanupDir(storageDisk, minioMetaBucket, tmpMetaPrefix)
+	err := cleanupDir(storageDisk, minioMetaBucket, tmpMetaPrefix)
 	if err != nil {
-		return err
+		return toObjectErr(err, minioMetaBucket, tmpMetaPrefix)
 	}
 	return nil
 }
@@ -70,8 +63,8 @@ func newStorageAPI(disk string) (storage StorageAPI, err error) {
 	return newRPCClient(disk)
 }
 
-// House keeping code needed for XL.
-func xlHouseKeeping(storageDisks []StorageAPI) error {
+// Initializes meta volume on all input storage disks.
+func initMetaVolume(storageDisks []StorageAPI) error {
 	// This happens for the first time, but keep this here since this
 	// is the only place where it can be made expensive optimizing all
 	// other calls. Create minio meta volume, if it doesn't exist yet.
@@ -93,17 +86,58 @@ func xlHouseKeeping(storageDisks []StorageAPI) error {
 
 			// Attempt to create `.minio`.
 			err := disk.MakeVol(minioMetaBucket)
-			if err != nil && err != errVolumeExists && err != errDiskNotFound && err != errFaultyDisk {
-				errs[index] = err
-				return
+			if err != nil {
+				switch err {
+				// Ignored errors.
+				case errVolumeExists, errDiskNotFound, errFaultyDisk:
+				default:
+					errs[index] = err
+				}
 			}
+		}(index, disk)
+	}
+
+	// Wait for all cleanup to finish.
+	wg.Wait()
+
+	// Return upon first error.
+	for _, err := range errs {
+		if err == nil {
+			continue
+		}
+		return toObjectErr(err, minioMetaBucket)
+	}
+
+	// Return success here.
+	return nil
+}
+
+// House keeping code needed for XL.
+func xlHouseKeeping(storageDisks []StorageAPI) error {
+	// This happens for the first time, but keep this here since this
+	// is the only place where it can be made expensive optimizing all
+	// other calls. Create metavolume.
+	var wg = &sync.WaitGroup{}
+
+	// Initialize errs to collect errors inside go-routine.
+	var errs = make([]error, len(storageDisks))
+
+	// Initialize all disks in parallel.
+	for index, disk := range storageDisks {
+		if disk == nil {
+			errs[index] = errDiskNotFound
+			continue
+		}
+		wg.Add(1)
+		go func(index int, disk StorageAPI) {
+			// Indicate this wait group is done.
+			defer wg.Done()
+
 			// Cleanup all temp entries upon start.
-			err = cleanupDir(disk, minioMetaBucket, tmpMetaPrefix)
+			err := cleanupDir(disk, minioMetaBucket, tmpMetaPrefix)
 			if err != nil {
 				errs[index] = err
-				return
 			}
-			errs[index] = nil
 		}(index, disk)
 	}
 

posix-utils_windows_test.go

@@ -144,7 +144,7 @@ func Test32kUNCPath(t *testing.T) {
 		// The following calculation was derived empirically. It is not exactly MAX_PATH - len(longDiskName)
 		// possibly due to expansion rules as mentioned here -
 		// https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247(v=vs.85).aspx#maxpath
-		remaining := 32767 - 25 - len(longDiskName)
+		remaining := 32767 - 25 - len(longDiskName) - 10
 		longDiskName = longDiskName + `\` + strings.Repeat("a", remaining)
 	}
 	err = mkdirAll(longDiskName, 0777)

posix.go

@@ -218,8 +218,13 @@ func (s *posix) MakeVol(volume string) (err error) {
 	}
 	// Make a volume entry, with mode 0777 mkdir honors system umask.
 	err = os.Mkdir(preparePath(volumeDir), 0777)
-	if err != nil && os.IsExist(err) {
-		return errVolumeExists
+	if err != nil {
+		if os.IsExist(err) {
+			return errVolumeExists
+		} else if os.IsPermission(err) {
+			return errDiskAccessDenied
+		}
+		return err
 	}
 	// Success
 	return nil

posix_test.go

@@ -19,6 +19,7 @@ package main
 import (
 	"io/ioutil"
 	"os"
+	"syscall"
 	"testing"
 )
 
@@ -114,3 +115,46 @@ func TestReadAll(t *testing.T) {
 		}
 	}
 }
+
+// TestNewPosix all the cases handled in posix storage layer initialization.
+func TestNewPosix(t *testing.T) {
+	// Temporary dir name.
+	tmpDirName := os.TempDir() + "/" + "minio-" + nextSuffix()
+	// Temporary file name.
+	tmpFileName := os.TempDir() + "/" + "minio-" + nextSuffix()
+	f, _ := os.Create(tmpFileName)
+	f.Close()
+	defer os.Remove(tmpFileName)
+
+	// List of all tests for posix initialization.
+	testCases := []struct {
+		diskPath string
+		err      error
+	}{
+		// Validates input argument cannot be empty.
+		{
+			"",
+			errInvalidArgument,
+		},
+		// Validates if the directory does not exist and
+		// gets automatically created.
+		{
+			tmpDirName,
+			nil,
+		},
+		// Validates if the disk exists as file and returns error
+		// not a directory.
+		{
+			tmpFileName,
+			syscall.ENOTDIR,
+		},
+	}
+
+	// Validate all test cases.
+	for i, testCase := range testCases {
+		_, err := newPosix(testCase.diskPath)
+		if err != testCase.err {
+			t.Fatalf("Test %d failed wanted: %s, got: %s", i+1, err, testCase.err)
+		}
+	}
+}

server_test.go

@@ -1912,7 +1912,7 @@ func (s *TestSuiteFS) TestObjectValidMD5(c *C) {
 	client = http.Client{}
 	response, err = client.Do(request)
 	c.Assert(err, IsNil)
-	// exepcting a successfull upload.
+	// exepcting a successful upload.
 	c.Assert(response.StatusCode, Equals, http.StatusOK)
 	objectName = "test-2-object"
 	buffer1 = bytes.NewReader(data)

storage-errors.go

@@ -33,6 +33,9 @@ var errDiskFull = errors.New("disk path full")
 // errDiskNotFount - cannot find the underlying configured disk anymore.
 var errDiskNotFound = errors.New("disk not found")
 
+// errDiskAccessDenied - we don't have write permissions on disk.
+var errDiskAccessDenied = errors.New("disk access denied")
+
 // errFileNotFound - cannot find the file.
 var errFileNotFound = errors.New("file not found")
 

test-utils_test.go

@@ -69,12 +69,12 @@ const (
 var randN uint32
 var randmu sync.Mutex
 
-// reseed - returns a new seed everytime the function is called.
+// reseed - returns a new seed every time the function is called.
 func reseed() uint32 {
 	return uint32(time.Now().UnixNano() + int64(os.Getpid()))
 }
 
-// nextSuffix - provides a new unique suffix everytime the function is called.
+// nextSuffix - provides a new unique suffix every time the function is called.
 func nextSuffix() string {
 	randmu.Lock()
 	r := randN

xl-v1.go

@@ -122,9 +122,6 @@ func newXLObjects(disks []string) (ObjectLayer, error) {
 		}
 	}
 
-	// Runs house keeping code, like creating minioMetaBucket, cleaning up tmp files etc.
-	xlHouseKeeping(storageDisks)
-
 	// Attempt to load all `format.json`.
 	formatConfigs, sErrs := loadAllFormats(storageDisks)
 
@@ -138,6 +135,9 @@ func newXLObjects(disks []string) (ObjectLayer, error) {
 	// Handles different cases properly.
 	switch reduceFormatErrs(sErrs, len(storageDisks)) {
 	case errUnformattedDisk:
+		if err := initMetaVolume(storageDisks); err != nil {
+			return nil, fmt.Errorf("Unable to initialize '.minio' meta volume, %s", err)
+		}
 		// All drives online but fresh, initialize format.
 		if err := initFormatXL(storageDisks); err != nil {
 			return nil, fmt.Errorf("Unable to initialize format, %s", err)
@@ -153,6 +153,11 @@ func newXLObjects(disks []string) (ObjectLayer, error) {
 		// FIXME.
 	}
 
+	// Runs house keeping code, like t, cleaning up tmp files etc.
+	if err := xlHouseKeeping(storageDisks); err != nil {
+		return nil, err
+	}
+
 	// Load saved XL format.json and validate.
 	newPosixDisks, err := loadFormatXL(storageDisks)
 	if err != nil {