Extract pkg/util/mount and drop BUILD

Preserving git history.

doc.go

@@ -0,0 +1,18 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// Package mount defines an interface to mounting filesystems.
+package mount // import "k8s.io/kubernetes/pkg/util/mount"

fake_mounter.go

@@ -0,0 +1,204 @@
+/*
+Copyright 2015 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"os"
+	"path/filepath"
+	"sync"
+
+	"k8s.io/klog"
+)
+
+// FakeMounter implements mount.Interface for tests.
+type FakeMounter struct {
+	MountPoints []MountPoint
+	log         []FakeAction
+	// Error to return for a path when calling IsLikelyNotMountPoint
+	MountCheckErrors map[string]error
+	// Some tests run things in parallel, make sure the mounter does not produce
+	// any golang's DATA RACE warnings.
+	mutex       sync.Mutex
+	UnmountFunc UnmountFunc
+}
+
+type UnmountFunc func(path string) error
+
+var _ Interface = &FakeMounter{}
+
+const (
+	// FakeActionMount is the string for specifying mount as FakeAction.Action
+	FakeActionMount = "mount"
+	// FakeActionUnmount is the string for specifying unmount as FakeAction.Action
+	FakeActionUnmount = "unmount"
+)
+
+// FakeAction objects are logged every time a fake mount or unmount is called.
+type FakeAction struct {
+	Action string // "mount" or "unmount"
+	Target string // applies to both mount and unmount actions
+	Source string // applies only to "mount" actions
+	FSType string // applies only to "mount" actions
+}
+
+func NewFakeMounter(mps []MountPoint) *FakeMounter {
+	return &FakeMounter{
+		MountPoints: mps,
+	}
+}
+
+// ResetLog clears all the log entries in FakeMounter
+func (f *FakeMounter) ResetLog() {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
+
+	f.log = []FakeAction{}
+}
+
+// GetLog returns the slice of FakeActions taken by the mounter
+func (f *FakeMounter) GetLog() []FakeAction {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
+
+	return f.log
+}
+
+// Mount records the mount event and updates the in-memory mount points for FakeMounter
+func (f *FakeMounter) Mount(source string, target string, fstype string, options []string) error {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
+
+	opts := []string{}
+
+	for _, option := range options {
+		// find 'bind' option
+		if option == "bind" {
+			// This is a bind-mount. In order to mimic linux behaviour, we must
+			// use the original device of the bind-mount as the real source.
+			// E.g. when mounted /dev/sda like this:
+			//      $ mount /dev/sda /mnt/test
+			//      $ mount -o bind /mnt/test /mnt/bound
+			// then /proc/mount contains:
+			// /dev/sda /mnt/test
+			// /dev/sda /mnt/bound
+			// (and not /mnt/test /mnt/bound)
+			// I.e. we must use /dev/sda as source instead of /mnt/test in the
+			// bind mount.
+			for _, mnt := range f.MountPoints {
+				if source == mnt.Path {
+					source = mnt.Device
+					break
+				}
+			}
+		}
+		// reuse MountPoint.Opts field to mark mount as readonly
+		opts = append(opts, option)
+	}
+
+	// If target is a symlink, get its absolute path
+	absTarget, err := filepath.EvalSymlinks(target)
+	if err != nil {
+		absTarget = target
+	}
+	f.MountPoints = append(f.MountPoints, MountPoint{Device: source, Path: absTarget, Type: fstype, Opts: opts})
+	klog.V(5).Infof("Fake mounter: mounted %s to %s", source, absTarget)
+	f.log = append(f.log, FakeAction{Action: FakeActionMount, Target: absTarget, Source: source, FSType: fstype})
+	return nil
+}
+
+// Unmount records the unmount event and updates the in-memory mount points for FakeMounter
+func (f *FakeMounter) Unmount(target string) error {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
+
+	// If target is a symlink, get its absolute path
+	absTarget, err := filepath.EvalSymlinks(target)
+	if err != nil {
+		absTarget = target
+	}
+
+	newMountpoints := []MountPoint{}
+	for _, mp := range f.MountPoints {
+		if mp.Path == absTarget {
+			if f.UnmountFunc != nil {
+				err := f.UnmountFunc(absTarget)
+				if err != nil {
+					return err
+				}
+			}
+			klog.V(5).Infof("Fake mounter: unmounted %s from %s", mp.Device, absTarget)
+			// Don't copy it to newMountpoints
+			continue
+		}
+		newMountpoints = append(newMountpoints, MountPoint{Device: mp.Device, Path: mp.Path, Type: mp.Type})
+	}
+	f.MountPoints = newMountpoints
+	f.log = append(f.log, FakeAction{Action: FakeActionUnmount, Target: absTarget})
+	delete(f.MountCheckErrors, target)
+	return nil
+}
+
+// List returns all the in-memory mountpoints for FakeMounter
+func (f *FakeMounter) List() ([]MountPoint, error) {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
+
+	return f.MountPoints, nil
+}
+
+// IsLikelyNotMountPoint determines whether a path is a mountpoint by checking
+// if the absolute path to file is in the in-memory mountpoints
+func (f *FakeMounter) IsLikelyNotMountPoint(file string) (bool, error) {
+	f.mutex.Lock()
+	defer f.mutex.Unlock()
+
+	err := f.MountCheckErrors[file]
+	if err != nil {
+		return false, err
+	}
+
+	_, err = os.Stat(file)
+	if err != nil {
+		return true, err
+	}
+
+	// If file is a symlink, get its absolute path
+	absFile, err := filepath.EvalSymlinks(file)
+	if err != nil {
+		absFile = file
+	}
+
+	for _, mp := range f.MountPoints {
+		if mp.Path == absFile {
+			klog.V(5).Infof("isLikelyNotMountPoint for %s: mounted %s, false", file, mp.Path)
+			return false, nil
+		}
+	}
+	klog.V(5).Infof("isLikelyNotMountPoint for %s: true", file)
+	return true, nil
+}
+
+// GetMountRefs finds all mount references to the path, returns a
+// list of paths.
+func (f *FakeMounter) GetMountRefs(pathname string) ([]string, error) {
+	realpath, err := filepath.EvalSymlinks(pathname)
+	if err != nil {
+		// Ignore error in FakeMounter, because we actually didn't create files.
+		realpath = pathname
+	}
+	return getMountRefsByDev(f, realpath)
+}

mount.go

@@ -0,0 +1,267 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+// TODO(thockin): This whole pkg is pretty linux-centric.  As soon as we have
+// an alternate platform, we will need to abstract further.
+
+package mount
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+
+	utilexec "k8s.io/utils/exec"
+)
+
+const (
+	// Default mount command if mounter path is not specified.
+	defaultMountCommand = "mount"
+)
+
+// Interface defines the set of methods to allow for mount operations on a system.
+type Interface interface {
+	// Mount mounts source to target as fstype with given options.
+	Mount(source string, target string, fstype string, options []string) error
+	// Unmount unmounts given target.
+	Unmount(target string) error
+	// List returns a list of all mounted filesystems.  This can be large.
+	// On some platforms, reading mounts directly from the OS is not guaranteed
+	// consistent (i.e. it could change between chunked reads). This is guaranteed
+	// to be consistent.
+	List() ([]MountPoint, error)
+	// IsLikelyNotMountPoint uses heuristics to determine if a directory
+	// is not a mountpoint.
+	// It should return ErrNotExist when the directory does not exist.
+	// IsLikelyNotMountPoint does NOT properly detect all mountpoint types
+	// most notably linux bind mounts and symbolic link. For callers that do not
+	// care about such situations, this is a faster alternative to calling List()
+	// and scanning that output.
+	IsLikelyNotMountPoint(file string) (bool, error)
+	// GetMountRefs finds all mount references to pathname, returning a slice of
+	// paths. Pathname can be a mountpoint path or a normal	directory
+	// (for bind mount). On Linux, pathname is excluded from the slice.
+	// For example, if /dev/sdc was mounted at /path/a and /path/b,
+	// GetMountRefs("/path/a") would return ["/path/b"]
+	// GetMountRefs("/path/b") would return ["/path/a"]
+	// On Windows there is no way to query all mount points; as long as pathname is
+	// a valid mount, it will be returned.
+	GetMountRefs(pathname string) ([]string, error)
+}
+
+// Compile-time check to ensure all Mounter implementations satisfy
+// the mount interface.
+var _ Interface = &Mounter{}
+
+// MountPoint represents a single line in /proc/mounts or /etc/fstab.
+type MountPoint struct {
+	Device string
+	Path   string
+	Type   string
+	Opts   []string
+	Freq   int
+	Pass   int
+}
+
+// SafeFormatAndMount probes a device to see if it is formatted.
+// Namely it checks to see if a file system is present. If so it
+// mounts it otherwise the device is formatted first then mounted.
+type SafeFormatAndMount struct {
+	Interface
+	Exec utilexec.Interface
+}
+
+// FormatAndMount formats the given disk, if needed, and mounts it.
+// That is if the disk is not formatted and it is not being mounted as
+// read-only it will format it first then mount it. Otherwise, if the
+// disk is already formatted or it is being mounted as read-only, it
+// will be mounted without formatting.
+func (mounter *SafeFormatAndMount) FormatAndMount(source string, target string, fstype string, options []string) error {
+	return mounter.formatAndMount(source, target, fstype, options)
+}
+
+// getMountRefsByDev finds all references to the device provided
+// by mountPath; returns a list of paths.
+// Note that mountPath should be path after the evaluation of any symblolic links.
+func getMountRefsByDev(mounter Interface, mountPath string) ([]string, error) {
+	mps, err := mounter.List()
+	if err != nil {
+		return nil, err
+	}
+
+	// Finding the device mounted to mountPath.
+	diskDev := ""
+	for i := range mps {
+		if mountPath == mps[i].Path {
+			diskDev = mps[i].Device
+			break
+		}
+	}
+
+	// Find all references to the device.
+	var refs []string
+	for i := range mps {
+		if mps[i].Device == diskDev || mps[i].Device == mountPath {
+			if mps[i].Path != mountPath {
+				refs = append(refs, mps[i].Path)
+			}
+		}
+	}
+	return refs, nil
+}
+
+// GetDeviceNameFromMount given a mnt point, find the device from /proc/mounts
+// returns the device name, reference count, and error code.
+func GetDeviceNameFromMount(mounter Interface, mountPath string) (string, int, error) {
+	mps, err := mounter.List()
+	if err != nil {
+		return "", 0, err
+	}
+
+	// Find the device name.
+	// FIXME if multiple devices mounted on the same mount path, only the first one is returned.
+	device := ""
+	// If mountPath is symlink, need get its target path.
+	slTarget, err := filepath.EvalSymlinks(mountPath)
+	if err != nil {
+		slTarget = mountPath
+	}
+	for i := range mps {
+		if mps[i].Path == slTarget {
+			device = mps[i].Device
+			break
+		}
+	}
+
+	// Find all references to the device.
+	refCount := 0
+	for i := range mps {
+		if mps[i].Device == device {
+			refCount++
+		}
+	}
+	return device, refCount, nil
+}
+
+// IsNotMountPoint determines if a directory is a mountpoint.
+// It should return ErrNotExist when the directory does not exist.
+// IsNotMountPoint is more expensive than IsLikelyNotMountPoint.
+// IsNotMountPoint detects bind mounts in linux.
+// IsNotMountPoint enumerates all the mountpoints using List() and
+// the list of mountpoints may be large, then it uses
+// isMountPointMatch to evaluate whether the directory is a mountpoint.
+func IsNotMountPoint(mounter Interface, file string) (bool, error) {
+	// IsLikelyNotMountPoint provides a quick check
+	// to determine whether file IS A mountpoint.
+	notMnt, notMntErr := mounter.IsLikelyNotMountPoint(file)
+	if notMntErr != nil && os.IsPermission(notMntErr) {
+		// We were not allowed to do the simple stat() check, e.g. on NFS with
+		// root_squash. Fall back to /proc/mounts check below.
+		notMnt = true
+		notMntErr = nil
+	}
+	if notMntErr != nil {
+		return notMnt, notMntErr
+	}
+	// identified as mountpoint, so return this fact.
+	if notMnt == false {
+		return notMnt, nil
+	}
+
+	// Resolve any symlinks in file, kernel would do the same and use the resolved path in /proc/mounts.
+	resolvedFile, err := filepath.EvalSymlinks(file)
+	if err != nil {
+		return true, err
+	}
+
+	// check all mountpoints since IsLikelyNotMountPoint
+	// is not reliable for some mountpoint types.
+	mountPoints, mountPointsErr := mounter.List()
+	if mountPointsErr != nil {
+		return notMnt, mountPointsErr
+	}
+	for _, mp := range mountPoints {
+		if isMountPointMatch(mp, resolvedFile) {
+			notMnt = false
+			break
+		}
+	}
+	return notMnt, nil
+}
+
+// MakeBindOpts detects whether a bind mount is being requested and makes the remount options to
+// use in case of bind mount, due to the fact that bind mount doesn't respect mount options.
+// The list equals:
+//   options - 'bind' + 'remount' (no duplicate)
+func MakeBindOpts(options []string) (bool, []string, []string) {
+	// Because we have an FD opened on the subpath bind mount, the "bind" option
+	// needs to be included, otherwise the mount target will error as busy if you
+	// remount as readonly.
+	//
+	// As a consequence, all read only bind mounts will no longer change the underlying
+	// volume mount to be read only.
+	bindRemountOpts := []string{"bind", "remount"}
+	bind := false
+	bindOpts := []string{"bind"}
+
+	// _netdev is a userspace mount option and does not automatically get added when
+	// bind mount is created and hence we must carry it over.
+	if checkForNetDev(options) {
+		bindOpts = append(bindOpts, "_netdev")
+	}
+
+	for _, option := range options {
+		switch option {
+		case "bind":
+			bind = true
+			break
+		case "remount":
+			break
+		default:
+			bindRemountOpts = append(bindRemountOpts, option)
+		}
+	}
+
+	return bind, bindOpts, bindRemountOpts
+}
+
+func checkForNetDev(options []string) bool {
+	for _, option := range options {
+		if option == "_netdev" {
+			return true
+		}
+	}
+	return false
+}
+
+// PathWithinBase checks if give path is within given base directory.
+func PathWithinBase(fullPath, basePath string) bool {
+	rel, err := filepath.Rel(basePath, fullPath)
+	if err != nil {
+		return false
+	}
+	if StartsWithBackstep(rel) {
+		// Needed to escape the base path.
+		return false
+	}
+	return true
+}
+
+// StartsWithBackstep checks if the given path starts with a backstep segment.
+func StartsWithBackstep(rel string) bool {
+	// normalize to / and check for ../
+	return rel == ".." || strings.HasPrefix(filepath.ToSlash(rel), "../")
+}

mount_helper_common.go

@@ -0,0 +1,99 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"fmt"
+	"os"
+
+	"k8s.io/klog"
+)
+
+// CleanupMountPoint unmounts the given path and deletes the remaining directory
+// if successful. If extensiveMountPointCheck is true IsNotMountPoint will be
+// called instead of IsLikelyNotMountPoint. IsNotMountPoint is more expensive
+// but properly handles bind mounts within the same fs.
+func CleanupMountPoint(mountPath string, mounter Interface, extensiveMountPointCheck bool) error {
+	pathExists, pathErr := PathExists(mountPath)
+	if !pathExists {
+		klog.Warningf("Warning: Unmount skipped because path does not exist: %v", mountPath)
+		return nil
+	}
+	corruptedMnt := IsCorruptedMnt(pathErr)
+	if pathErr != nil && !corruptedMnt {
+		return fmt.Errorf("Error checking path: %v", pathErr)
+	}
+	return doCleanupMountPoint(mountPath, mounter, extensiveMountPointCheck, corruptedMnt)
+}
+
+// doCleanupMountPoint unmounts the given path and
+// deletes the remaining directory if successful.
+// if extensiveMountPointCheck is true
+// IsNotMountPoint will be called instead of IsLikelyNotMountPoint.
+// IsNotMountPoint is more expensive but properly handles bind mounts within the same fs.
+// if corruptedMnt is true, it means that the mountPath is a corrupted mountpoint, and the mount point check
+// will be skipped
+func doCleanupMountPoint(mountPath string, mounter Interface, extensiveMountPointCheck bool, corruptedMnt bool) error {
+	if !corruptedMnt {
+		var notMnt bool
+		var err error
+		if extensiveMountPointCheck {
+			notMnt, err = IsNotMountPoint(mounter, mountPath)
+		} else {
+			notMnt, err = mounter.IsLikelyNotMountPoint(mountPath)
+		}
+
+		if err != nil {
+			return err
+		}
+
+		if notMnt {
+			klog.Warningf("Warning: %q is not a mountpoint, deleting", mountPath)
+			return os.Remove(mountPath)
+		}
+	}
+
+	// Unmount the mount path
+	klog.V(4).Infof("%q is a mountpoint, unmounting", mountPath)
+	if err := mounter.Unmount(mountPath); err != nil {
+		return err
+	}
+
+	notMnt, mntErr := mounter.IsLikelyNotMountPoint(mountPath)
+	if mntErr != nil {
+		return mntErr
+	}
+	if notMnt {
+		klog.V(4).Infof("%q is unmounted, deleting the directory", mountPath)
+		return os.Remove(mountPath)
+	}
+	return fmt.Errorf("Failed to unmount path %v", mountPath)
+}
+
+// PathExists returns true if the specified path exists.
+// TODO: clean this up to use pkg/util/file/FileExists
+func PathExists(path string) (bool, error) {
+	_, err := os.Stat(path)
+	if err == nil {
+		return true, nil
+	} else if os.IsNotExist(err) {
+		return false, nil
+	} else if IsCorruptedMnt(err) {
+		return true, err
+	}
+	return false, err
+}

mount_helper_test.go

@@ -0,0 +1,139 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"runtime"
+	"syscall"
+	"testing"
+)
+
+func TestDoCleanupMountPoint(t *testing.T) {
+
+	if runtime.GOOS == "darwin" {
+		t.Skipf("not supported on GOOS=%s", runtime.GOOS)
+	}
+
+	const testMount = "test-mount"
+	const defaultPerm = 0750
+
+	tests := map[string]struct {
+		corruptedMnt bool
+		// Function that prepares the directory structure for the test under
+		// the given base directory.
+		// Returns a fake MountPoint, a fake error for the mount point,
+		// and error if the prepare function encountered a fatal error.
+		prepare   func(base string) (MountPoint, error, error)
+		expectErr bool
+	}{
+		"mount-ok": {
+			prepare: func(base string) (MountPoint, error, error) {
+				path := filepath.Join(base, testMount)
+				if err := os.MkdirAll(path, defaultPerm); err != nil {
+					return MountPoint{}, nil, err
+				}
+				return MountPoint{Device: "/dev/sdb", Path: path}, nil, nil
+			},
+		},
+		"mount-corrupted": {
+			prepare: func(base string) (MountPoint, error, error) {
+				path := filepath.Join(base, testMount)
+				if err := os.MkdirAll(path, defaultPerm); err != nil {
+					return MountPoint{}, nil, err
+				}
+				return MountPoint{Device: "/dev/sdb", Path: path}, os.NewSyscallError("fake", syscall.ESTALE), nil
+			},
+			corruptedMnt: true,
+		},
+		"mount-err-not-corrupted": {
+			prepare: func(base string) (MountPoint, error, error) {
+				path := filepath.Join(base, testMount)
+				if err := os.MkdirAll(path, defaultPerm); err != nil {
+					return MountPoint{}, nil, err
+				}
+				return MountPoint{Device: "/dev/sdb", Path: path}, os.NewSyscallError("fake", syscall.ETIMEDOUT), nil
+			},
+			expectErr: true,
+		},
+	}
+
+	for name, tt := range tests {
+		t.Run(name, func(t *testing.T) {
+
+			tmpDir, err := ioutil.TempDir("", "unmount-mount-point-test")
+			if err != nil {
+				t.Fatalf("failed to create tmpdir: %v", err)
+			}
+			defer os.RemoveAll(tmpDir)
+
+			if tt.prepare == nil {
+				t.Fatalf("prepare function required")
+			}
+
+			mountPoint, mountError, err := tt.prepare(tmpDir)
+			if err != nil {
+				t.Fatalf("failed to prepare test: %v", err)
+			}
+
+			fake := NewFakeMounter(
+				[]MountPoint{mountPoint},
+			)
+			fake.MountCheckErrors = map[string]error{mountPoint.Path: mountError}
+
+			err = doCleanupMountPoint(mountPoint.Path, fake, true, tt.corruptedMnt)
+			if tt.expectErr {
+				if err == nil {
+					t.Errorf("test %s failed, expected error, got none", name)
+				}
+				if err := validateDirExists(mountPoint.Path); err != nil {
+					t.Errorf("test %s failed, mount path doesn't exist: %v", name, err)
+				}
+			}
+			if !tt.expectErr {
+				if err != nil {
+					t.Errorf("test %s failed: %v", name, err)
+				}
+				if err := validateDirNotExists(mountPoint.Path); err != nil {
+					t.Errorf("test %s failed, mount path still exists: %v", name, err)
+				}
+			}
+		})
+	}
+}
+
+func validateDirExists(dir string) error {
+	_, err := ioutil.ReadDir(dir)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func validateDirNotExists(dir string) error {
+	_, err := ioutil.ReadDir(dir)
+	if os.IsNotExist(err) {
+		return nil
+	}
+	if err != nil {
+		return err
+	}
+	return fmt.Errorf("dir %q still exists", dir)
+}

mount_helper_unix.go

@@ -0,0 +1,140 @@
+// +build !windows
+
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"syscall"
+
+	utilio "k8s.io/utils/io"
+)
+
+const (
+	// At least number of fields per line in /proc/<pid>/mountinfo.
+	expectedAtLeastNumFieldsPerMountInfo = 10
+	// How many times to retry for a consistent read of /proc/mounts.
+	maxListTries = 3
+)
+
+// IsCorruptedMnt return true if err is about corrupted mount point
+func IsCorruptedMnt(err error) bool {
+	if err == nil {
+		return false
+	}
+	var underlyingError error
+	switch pe := err.(type) {
+	case nil:
+		return false
+	case *os.PathError:
+		underlyingError = pe.Err
+	case *os.LinkError:
+		underlyingError = pe.Err
+	case *os.SyscallError:
+		underlyingError = pe.Err
+	}
+
+	return underlyingError == syscall.ENOTCONN || underlyingError == syscall.ESTALE || underlyingError == syscall.EIO || underlyingError == syscall.EACCES
+}
+
+// MountInfo represents a single line in /proc/<pid>/mountinfo.
+type MountInfo struct {
+	// Unique ID for the mount (maybe reused after umount).
+	ID int
+	// The ID of the parent mount (or of self for the root of this mount namespace's mount tree).
+	ParentID int
+	// The value of `st_dev` for files on this filesystem.
+	MajorMinor string
+	// The pathname of the directory in the filesystem which forms the root of this mount.
+	Root string
+	// Mount source, filesystem-specific information. e.g. device, tmpfs name.
+	Source string
+	// Mount point, the pathname of the mount point.
+	MountPoint string
+	// Optional fieds, zero or more fields of the form "tag[:value]".
+	OptionalFields []string
+	// The filesystem type in the form "type[.subtype]".
+	FsType string
+	// Per-mount options.
+	MountOptions []string
+	// Per-superblock options.
+	SuperOptions []string
+}
+
+// ParseMountInfo parses /proc/xxx/mountinfo.
+func ParseMountInfo(filename string) ([]MountInfo, error) {
+	content, err := utilio.ConsistentRead(filename, maxListTries)
+	if err != nil {
+		return []MountInfo{}, err
+	}
+	contentStr := string(content)
+	infos := []MountInfo{}
+
+	for _, line := range strings.Split(contentStr, "\n") {
+		if line == "" {
+			// the last split() item is empty string following the last \n
+			continue
+		}
+		// See `man proc` for authoritative description of format of the file.
+		fields := strings.Fields(line)
+		if len(fields) < expectedAtLeastNumFieldsPerMountInfo {
+			return nil, fmt.Errorf("wrong number of fields in (expected at least %d, got %d): %s", expectedAtLeastNumFieldsPerMountInfo, len(fields), line)
+		}
+		id, err := strconv.Atoi(fields[0])
+		if err != nil {
+			return nil, err
+		}
+		parentID, err := strconv.Atoi(fields[1])
+		if err != nil {
+			return nil, err
+		}
+		info := MountInfo{
+			ID:           id,
+			ParentID:     parentID,
+			MajorMinor:   fields[2],
+			Root:         fields[3],
+			MountPoint:   fields[4],
+			MountOptions: strings.Split(fields[5], ","),
+		}
+		// All fields until "-" are "optional fields".
+		i := 6
+		for ; i < len(fields) && fields[i] != "-"; i++ {
+			info.OptionalFields = append(info.OptionalFields, fields[i])
+		}
+		// Parse the rest 3 fields.
+		i++
+		if len(fields)-i < 3 {
+			return nil, fmt.Errorf("expect 3 fields in %s, got %d", line, len(fields)-i)
+		}
+		info.FsType = fields[i]
+		info.Source = fields[i+1]
+		info.SuperOptions = strings.Split(fields[i+2], ",")
+		infos = append(infos, info)
+	}
+	return infos, nil
+}
+
+// isMountPointMatch returns true if the path in mp is the same as dir.
+// Handles case where mountpoint dir has been renamed due to stale NFS mount.
+func isMountPointMatch(mp MountPoint, dir string) bool {
+	deletedDir := fmt.Sprintf("%s\\040(deleted)", dir)
+	return ((mp.Path == dir) || (mp.Path == deletedDir))
+}

mount_helper_unix_test.go

@@ -0,0 +1,215 @@
+// +build !windows
+
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"reflect"
+	"testing"
+)
+
+func writeFile(content string) (string, string, error) {
+	tempDir, err := ioutil.TempDir("", "mounter_shared_test")
+	if err != nil {
+		return "", "", err
+	}
+	filename := filepath.Join(tempDir, "mountinfo")
+	err = ioutil.WriteFile(filename, []byte(content), 0600)
+	if err != nil {
+		os.RemoveAll(tempDir)
+		return "", "", err
+	}
+	return tempDir, filename, nil
+}
+
+func TestParseMountInfo(t *testing.T) {
+	info :=
+		`62 0 253:0 / / rw,relatime shared:1 - ext4 /dev/mapper/ssd-root rw,seclabel,data=ordered
+78 62 0:41 / /tmp rw,nosuid,nodev shared:30 - tmpfs tmpfs rw,seclabel
+80 62 0:42 / /var/lib/nfs/rpc_pipefs rw,relatime shared:31 - rpc_pipefs sunrpc rw
+82 62 0:43 / /var/lib/foo rw,relatime shared:32 - tmpfs tmpfs rw
+83 63 0:44 / /var/lib/bar rw,relatime - tmpfs tmpfs rw
+227 62 253:0 /var/lib/docker/devicemapper /var/lib/docker/devicemapper rw,relatime - ext4 /dev/mapper/ssd-root rw,seclabel,data=ordered
+224 62 253:0 /var/lib/docker/devicemapper/test/shared /var/lib/docker/devicemapper/test/shared rw,relatime master:1 shared:44 - ext4 /dev/mapper/ssd-root rw,seclabel,data=ordered
+76 17 8:1 / /mnt/stateful_partition rw,nosuid,nodev,noexec,relatime - ext4 /dev/sda1 rw,commit=30,data=ordered
+80 17 8:1 /var /var rw,nosuid,nodev,noexec,relatime shared:30 - ext4 /dev/sda1 rw,commit=30,data=ordered
+189 80 8:1 /var/lib/kubelet /var/lib/kubelet rw,relatime shared:30 - ext4 /dev/sda1 rw,commit=30,data=ordered
+818 77 8:40 / /var/lib/kubelet/pods/c25464af-e52e-11e7-ab4d-42010a800002/volumes/kubernetes.io~gce-pd/vol1 rw,relatime shared:290 - ext4 /dev/sdc rw,data=ordered
+819 78 8:48 / /var/lib/kubelet/pods/c25464af-e52e-11e7-ab4d-42010a800002/volumes/kubernetes.io~gce-pd/vol1 rw,relatime shared:290 - ext4 /dev/sdd rw,data=ordered
+900 100 8:48 /dir1 /var/lib/kubelet/pods/c25464af-e52e-11e7-ab4d-42010a800002/volume-subpaths/vol1/subpath1/0 rw,relatime shared:290 - ext4 /dev/sdd rw,data=ordered
+901 101 8:1 /dir1 /var/lib/kubelet/pods/c25464af-e52e-11e7-ab4d-42010a800002/volume-subpaths/vol1/subpath1/1 rw,relatime shared:290 - ext4 /dev/sdd rw,data=ordered
+902 102 8:1 /var/lib/kubelet/pods/d4076f24-e53a-11e7-ba15-42010a800002/volumes/kubernetes.io~empty-dir/vol1/dir1 /var/lib/kubelet/pods/d4076f24-e53a-11e7-ba15-42010a800002/volume-subpaths/vol1/subpath1/0 rw,relatime shared:30 - ext4 /dev/sda1 rw,commit=30,data=ordered
+903 103 8:1 /var/lib/kubelet/pods/d4076f24-e53a-11e7-ba15-42010a800002/volumes/kubernetes.io~empty-dir/vol2/dir1 /var/lib/kubelet/pods/d4076f24-e53a-11e7-ba15-42010a800002/volume-subpaths/vol1/subpath1/1 rw,relatime shared:30 - ext4 /dev/sda1 rw,commit=30,data=ordered
+178 25 253:0 /etc/bar /var/lib/kubelet/pods/12345/volume-subpaths/vol1/subpath1/0 rw,relatime shared:1 - ext4 /dev/sdb2 rw,errors=remount-ro,data=ordered
+698 186 0:41 /tmp1/dir1 /var/lib/kubelet/pods/41135147-e697-11e7-9342-42010a800002/volume-subpaths/vol1/subpath1/0 rw shared:26 - tmpfs tmpfs rw
+918 77 8:50 / /var/lib/kubelet/pods/2345/volumes/kubernetes.io~gce-pd/vol1 rw,relatime shared:290 - ext4 /dev/sdc rw,data=ordered
+919 78 8:58 / /var/lib/kubelet/pods/2345/volumes/kubernetes.io~gce-pd/vol1 rw,relatime shared:290 - ext4 /dev/sdd rw,data=ordered
+920 100 8:50 /dir1 /var/lib/kubelet/pods/2345/volume-subpaths/vol1/subpath1/0 rw,relatime shared:290 - ext4 /dev/sdc rw,data=ordered
+150 23 1:58 / /media/nfs_vol rw,relatime shared:89 - nfs4 172.18.4.223:/srv/nfs rw,vers=4.0,rsize=524288,wsize=524288,namlen=255,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=172.18.4.223,local_lock=none,addr=172.18.4.223
+151 24 1:58 / /media/nfs_bindmount rw,relatime shared:89 - nfs4 172.18.4.223:/srv/nfs/foo rw,vers=4.0,rsize=524288,wsize=524288,namlen=255,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=172.18.4.223,local_lock=none,addr=172.18.4.223
+134 23 0:58 / /var/lib/kubelet/pods/43219158-e5e1-11e7-a392-0e858b8eaf40/volumes/kubernetes.io~nfs/nfs1 rw,relatime shared:89 - nfs4 172.18.4.223:/srv/nfs rw,vers=4.0,rsize=524288,wsize=524288,namlen=255,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=172.18.4.223,local_lock=none,addr=172.18.4.223
+187 23 0:58 / /var/lib/kubelet/pods/1fc5ea21-eff4-11e7-ac80-0e858b8eaf40/volumes/kubernetes.io~nfs/nfs2 rw,relatime shared:96 - nfs4 172.18.4.223:/srv/nfs2 rw,vers=4.0,rsize=524288,wsize=524288,namlen=255,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=172.18.4.223,local_lock=none,addr=172.18.4.223
+188 24 0:58 / /var/lib/kubelet/pods/43219158-e5e1-11e7-a392-0e858b8eaf40/volume-subpaths/nfs1/subpath1/0 rw,relatime shared:89 - nfs4 172.18.4.223:/srv/nfs/foo rw,vers=4.0,rsize=524288,wsize=524288,namlen=255,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=172.18.4.223,local_lock=none,addr=172.18.4.223
+347 60 0:71 / /var/lib/kubelet/pods/13195d46-f9fa-11e7-bbf1-5254007a695a/volumes/kubernetes.io~nfs/vol2 rw,relatime shared:170 - nfs 172.17.0.3:/exports/2 rw,vers=3,rsize=1048576,wsize=1048576,namlen=255,hard,proto=tcp,timeo=600,retrans=2,sec=sys,mountaddr=172.17.0.3,mountvers=3,mountport=20048,mountproto=udp,local_lock=none,addr=172.17.0.3
+222 24 253:0 /tmp/src /mnt/dst rw,relatime shared:1 - ext4 /dev/mapper/vagrant--vg-root rw,errors=remount-ro,data=ordered
+28 18 0:24 / /sys/fs/cgroup ro,nosuid,nodev,noexec shared:9 - tmpfs tmpfs ro,mode=755
+29 28 0:25 / /sys/fs/cgroup/systemd rw,nosuid,nodev,noexec,relatime shared:10 - cgroup cgroup rw,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd
+31 28 0:27 / /sys/fs/cgroup/cpuset rw,nosuid,nodev,noexec,relatime shared:13 - cgroup cgroup rw,cpuset
+32 28 0:28 / /sys/fs/cgroup/cpu,cpuacct rw,nosuid,nodev,noexec,relatime shared:14 - cgroup cgroup rw,cpu,cpuacct
+33 28 0:29 / /sys/fs/cgroup/freezer rw,nosuid,nodev,noexec,relatime shared:15 - cgroup cgroup rw,freezer
+34 28 0:30 / /sys/fs/cgroup/net_cls,net_prio rw,nosuid,nodev,noexec,relatime shared:16 - cgroup cgroup rw,net_cls,net_prio
+35 28 0:31 / /sys/fs/cgroup/pids rw,nosuid,nodev,noexec,relatime shared:17 - cgroup cgroup rw,pids
+36 28 0:32 / /sys/fs/cgroup/devices rw,nosuid,nodev,noexec,relatime shared:18 - cgroup cgroup rw,devices
+37 28 0:33 / /sys/fs/cgroup/hugetlb rw,nosuid,nodev,noexec,relatime shared:19 - cgroup cgroup rw,hugetlb
+38 28 0:34 / /sys/fs/cgroup/blkio rw,nosuid,nodev,noexec,relatime shared:20 - cgroup cgroup rw,blkio
+39 28 0:35 / /sys/fs/cgroup/memory rw,nosuid,nodev,noexec,relatime shared:21 - cgroup cgroup rw,memory
+40 28 0:36 / /sys/fs/cgroup/perf_event rw,nosuid,nodev,noexec,relatime shared:22 - cgroup cgroup rw,perf_event
+`
+	tempDir, filename, err := writeFile(info)
+	if err != nil {
+		t.Fatalf("cannot create temporary file: %v", err)
+	}
+	defer os.RemoveAll(tempDir)
+
+	tests := []struct {
+		name         string
+		id           int
+		expectedInfo MountInfo
+	}{
+		{
+			"simple bind mount",
+			189,
+			MountInfo{
+				ID:             189,
+				ParentID:       80,
+				MajorMinor:     "8:1",
+				Root:           "/var/lib/kubelet",
+				Source:         "/dev/sda1",
+				MountPoint:     "/var/lib/kubelet",
+				OptionalFields: []string{"shared:30"},
+				FsType:         "ext4",
+				MountOptions:   []string{"rw", "relatime"},
+				SuperOptions:   []string{"rw", "commit=30", "data=ordered"},
+			},
+		},
+		{
+			"bind mount a directory",
+			222,
+			MountInfo{
+				ID:             222,
+				ParentID:       24,
+				MajorMinor:     "253:0",
+				Root:           "/tmp/src",
+				Source:         "/dev/mapper/vagrant--vg-root",
+				MountPoint:     "/mnt/dst",
+				OptionalFields: []string{"shared:1"},
+				FsType:         "ext4",
+				MountOptions:   []string{"rw", "relatime"},
+				SuperOptions:   []string{"rw", "errors=remount-ro", "data=ordered"},
+			},
+		},
+		{
+			"more than one optional fields",
+			224,
+			MountInfo{
+				ID:             224,
+				ParentID:       62,
+				MajorMinor:     "253:0",
+				Root:           "/var/lib/docker/devicemapper/test/shared",
+				Source:         "/dev/mapper/ssd-root",
+				MountPoint:     "/var/lib/docker/devicemapper/test/shared",
+				OptionalFields: []string{"master:1", "shared:44"},
+				FsType:         "ext4",
+				MountOptions:   []string{"rw", "relatime"},
+				SuperOptions:   []string{"rw", "seclabel", "data=ordered"},
+			},
+		},
+		{
+			"cgroup-mountpoint",
+			28,
+			MountInfo{
+				ID:             28,
+				ParentID:       18,
+				MajorMinor:     "0:24",
+				Root:           "/",
+				Source:         "tmpfs",
+				MountPoint:     "/sys/fs/cgroup",
+				OptionalFields: []string{"shared:9"},
+				FsType:         "tmpfs",
+				MountOptions:   []string{"ro", "nosuid", "nodev", "noexec"},
+				SuperOptions:   []string{"ro", "mode=755"},
+			},
+		},
+		{
+			"cgroup-subsystem-systemd-mountpoint",
+			29,
+			MountInfo{
+				ID:             29,
+				ParentID:       28,
+				MajorMinor:     "0:25",
+				Root:           "/",
+				Source:         "cgroup",
+				MountPoint:     "/sys/fs/cgroup/systemd",
+				OptionalFields: []string{"shared:10"},
+				FsType:         "cgroup",
+				MountOptions:   []string{"rw", "nosuid", "nodev", "noexec", "relatime"},
+				SuperOptions:   []string{"rw", "xattr", "release_agent=/lib/systemd/systemd-cgroups-agent", "name=systemd"},
+			},
+		},
+		{
+			"cgroup-subsystem-cpuset-mountpoint",
+			31,
+			MountInfo{
+				ID:             31,
+				ParentID:       28,
+				MajorMinor:     "0:27",
+				Root:           "/",
+				Source:         "cgroup",
+				MountPoint:     "/sys/fs/cgroup/cpuset",
+				OptionalFields: []string{"shared:13"},
+				FsType:         "cgroup",
+				MountOptions:   []string{"rw", "nosuid", "nodev", "noexec", "relatime"},
+				SuperOptions:   []string{"rw", "cpuset"},
+			},
+		},
+	}
+
+	infos, err := ParseMountInfo(filename)
+	if err != nil {
+		t.Fatalf("Cannot parse %s: %s", filename, err)
+	}
+
+	for _, test := range tests {
+		found := false
+		for _, info := range infos {
+			if info.ID == test.id {
+				found = true
+				if !reflect.DeepEqual(info, test.expectedInfo) {
+					t.Errorf("Test case %q:\n expected: %+v\n got:      %+v", test.name, test.expectedInfo, info)
+				}
+				break
+			}
+		}
+		if !found {
+			t.Errorf("Test case %q: mountPoint %d not found", test.name, test.id)
+		}
+	}
+}

mount_helper_windows.go

@@ -0,0 +1,98 @@
+// +build windows
+
+/*
+Copyright 2019 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+	"syscall"
+
+	"k8s.io/klog"
+)
+
+// following failure codes are from https://docs.microsoft.com/en-us/windows/desktop/debug/system-error-codes--1300-1699-
+// ERROR_BAD_NETPATH                 = 53
+// ERROR_NETWORK_BUSY                = 54
+// ERROR_UNEXP_NET_ERR               = 59
+// ERROR_NETNAME_DELETED             = 64
+// ERROR_NETWORK_ACCESS_DENIED       = 65
+// ERROR_BAD_DEV_TYPE                = 66
+// ERROR_BAD_NET_NAME                = 67
+// ERROR_SESSION_CREDENTIAL_CONFLICT = 1219
+// ERROR_LOGON_FAILURE               = 1326
+var errorNoList = [...]int{53, 54, 59, 64, 65, 66, 67, 1219, 1326}
+
+// IsCorruptedMnt return true if err is about corrupted mount point
+func IsCorruptedMnt(err error) bool {
+	if err == nil {
+		return false
+	}
+
+	var underlyingError error
+	switch pe := err.(type) {
+	case nil:
+		return false
+	case *os.PathError:
+		underlyingError = pe.Err
+	case *os.LinkError:
+		underlyingError = pe.Err
+	case *os.SyscallError:
+		underlyingError = pe.Err
+	}
+
+	if ee, ok := underlyingError.(syscall.Errno); ok {
+		for _, errno := range errorNoList {
+			if int(ee) == errno {
+				klog.Warningf("IsCorruptedMnt failed with error: %v, error code: %v", err, errno)
+				return true
+			}
+		}
+	}
+
+	return false
+}
+
+func NormalizeWindowsPath(path string) string {
+	normalizedPath := strings.Replace(path, "/", "\\", -1)
+	if strings.HasPrefix(normalizedPath, "\\") {
+		normalizedPath = "c:" + normalizedPath
+	}
+	return normalizedPath
+}
+
+// ValidateDiskNumber : disk number should be a number in [0, 99]
+func ValidateDiskNumber(disk string) error {
+	diskNum, err := strconv.Atoi(disk)
+	if err != nil {
+		return fmt.Errorf("wrong disk number format: %q, err:%v", disk, err)
+	}
+
+	if diskNum < 0 || diskNum > 99 {
+		return fmt.Errorf("disk number out of range: %q", disk)
+	}
+
+	return nil
+}
+
+// isMountPointMatch determines if the mountpoint matches the dir
+func isMountPointMatch(mp MountPoint, dir string) bool {
+	return mp.Path == dir
+}

mount_helper_windows_test.go

@@ -0,0 +1,65 @@
+// +build windows
+
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"testing"
+)
+
+func TestNormalizeWindowsPath(t *testing.T) {
+	path := `/var/lib/kubelet/pods/146f8428-83e7-11e7-8dd4-000d3a31dac4/volumes/kubernetes.io~azure-disk`
+	normalizedPath := NormalizeWindowsPath(path)
+	if normalizedPath != `c:\var\lib\kubelet\pods\146f8428-83e7-11e7-8dd4-000d3a31dac4\volumes\kubernetes.io~azure-disk` {
+		t.Errorf("normizeWindowsPath test failed, normalizedPath : %q", normalizedPath)
+	}
+
+	path = `/var/lib/kubelet/pods/146f8428-83e7-11e7-8dd4-000d3a31dac4\volumes\kubernetes.io~azure-disk`
+	normalizedPath = NormalizeWindowsPath(path)
+	if normalizedPath != `c:\var\lib\kubelet\pods\146f8428-83e7-11e7-8dd4-000d3a31dac4\volumes\kubernetes.io~azure-disk` {
+		t.Errorf("normizeWindowsPath test failed, normalizedPath : %q", normalizedPath)
+	}
+
+	path = `/`
+	normalizedPath = NormalizeWindowsPath(path)
+	if normalizedPath != `c:\` {
+		t.Errorf("normizeWindowsPath test failed, normalizedPath : %q", normalizedPath)
+	}
+}
+
+func TestValidateDiskNumber(t *testing.T) {
+	diskNum := "0"
+	if err := ValidateDiskNumber(diskNum); err != nil {
+		t.Errorf("TestValidateDiskNumber test failed, disk number : %s", diskNum)
+	}
+
+	diskNum = "99"
+	if err := ValidateDiskNumber(diskNum); err != nil {
+		t.Errorf("TestValidateDiskNumber test failed, disk number : %s", diskNum)
+	}
+
+	diskNum = "ab"
+	if err := ValidateDiskNumber(diskNum); err == nil {
+		t.Errorf("TestValidateDiskNumber test failed, disk number : %s", diskNum)
+	}
+
+	diskNum = "100"
+	if err := ValidateDiskNumber(diskNum); err == nil {
+		t.Errorf("TestValidateDiskNumber test failed, disk number : %s", diskNum)
+	}
+}

mount_linux.go

@@ -0,0 +1,489 @@
+// +build linux
+
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"syscall"
+
+	"k8s.io/klog"
+	utilexec "k8s.io/utils/exec"
+	utilio "k8s.io/utils/io"
+)
+
+const (
+	// Number of fields per line in /proc/mounts as per the fstab man page.
+	expectedNumFieldsPerLine = 6
+	// Location of the mount file to use
+	procMountsPath = "/proc/mounts"
+	// Location of the mountinfo file
+	procMountInfoPath = "/proc/self/mountinfo"
+	// 'fsck' found errors and corrected them
+	fsckErrorsCorrected = 1
+	// 'fsck' found errors but exited without correcting them
+	fsckErrorsUncorrected = 4
+)
+
+// Mounter provides the default implementation of mount.Interface
+// for the linux platform.  This implementation assumes that the
+// kubelet is running in the host's root mount namespace.
+type Mounter struct {
+	mounterPath string
+	withSystemd bool
+}
+
+// New returns a mount.Interface for the current system.
+// It provides options to override the default mounter behavior.
+// mounterPath allows using an alternative to `/bin/mount` for mounting.
+func New(mounterPath string) Interface {
+	return &Mounter{
+		mounterPath: mounterPath,
+		withSystemd: detectSystemd(),
+	}
+}
+
+// Mount mounts source to target as fstype with given options. 'source' and 'fstype' must
+// be an empty string in case it's not required, e.g. for remount, or for auto filesystem
+// type, where kernel handles fstype for you. The mount 'options' is a list of options,
+// currently come from mount(8), e.g. "ro", "remount", "bind", etc. If no more option is
+// required, call Mount with an empty string list or nil.
+func (mounter *Mounter) Mount(source string, target string, fstype string, options []string) error {
+	// Path to mounter binary if containerized mounter is needed. Otherwise, it is set to empty.
+	// All Linux distros are expected to be shipped with a mount utility that a support bind mounts.
+	mounterPath := ""
+	bind, bindOpts, bindRemountOpts := MakeBindOpts(options)
+	if bind {
+		err := mounter.doMount(mounterPath, defaultMountCommand, source, target, fstype, bindOpts)
+		if err != nil {
+			return err
+		}
+		return mounter.doMount(mounterPath, defaultMountCommand, source, target, fstype, bindRemountOpts)
+	}
+	// The list of filesystems that require containerized mounter on GCI image cluster
+	fsTypesNeedMounter := map[string]struct{}{
+		"nfs":       {},
+		"glusterfs": {},
+		"ceph":      {},
+		"cifs":      {},
+	}
+	if _, ok := fsTypesNeedMounter[fstype]; ok {
+		mounterPath = mounter.mounterPath
+	}
+	return mounter.doMount(mounterPath, defaultMountCommand, source, target, fstype, options)
+}
+
+// doMount runs the mount command. mounterPath is the path to mounter binary if containerized mounter is used.
+func (mounter *Mounter) doMount(mounterPath string, mountCmd string, source string, target string, fstype string, options []string) error {
+	mountArgs := MakeMountArgs(source, target, fstype, options)
+	if len(mounterPath) > 0 {
+		mountArgs = append([]string{mountCmd}, mountArgs...)
+		mountCmd = mounterPath
+	}
+
+	if mounter.withSystemd {
+		// Try to run mount via systemd-run --scope. This will escape the
+		// service where kubelet runs and any fuse daemons will be started in a
+		// specific scope. kubelet service than can be restarted without killing
+		// these fuse daemons.
+		//
+		// Complete command line (when mounterPath is not used):
+		// systemd-run --description=... --scope -- mount -t <type> <what> <where>
+		//
+		// Expected flow:
+		// * systemd-run creates a transient scope (=~ cgroup) and executes its
+		//   argument (/bin/mount) there.
+		// * mount does its job, forks a fuse daemon if necessary and finishes.
+		//   (systemd-run --scope finishes at this point, returning mount's exit
+		//   code and stdout/stderr - thats one of --scope benefits).
+		// * systemd keeps the fuse daemon running in the scope (i.e. in its own
+		//   cgroup) until the fuse daemon dies (another --scope benefit).
+		//   Kubelet service can be restarted and the fuse daemon survives.
+		// * When the fuse daemon dies (e.g. during unmount) systemd removes the
+		//   scope automatically.
+		//
+		// systemd-mount is not used because it's too new for older distros
+		// (CentOS 7, Debian Jessie).
+		mountCmd, mountArgs = AddSystemdScope("systemd-run", target, mountCmd, mountArgs)
+	} else {
+		// No systemd-run on the host (or we failed to check it), assume kubelet
+		// does not run as a systemd service.
+		// No code here, mountCmd and mountArgs are already populated.
+	}
+
+	klog.V(4).Infof("Mounting cmd (%s) with arguments (%s)", mountCmd, mountArgs)
+	command := exec.Command(mountCmd, mountArgs...)
+	output, err := command.CombinedOutput()
+	if err != nil {
+		args := strings.Join(mountArgs, " ")
+		klog.Errorf("Mount failed: %v\nMounting command: %s\nMounting arguments: %s\nOutput: %s\n", err, mountCmd, args, string(output))
+		return fmt.Errorf("mount failed: %v\nMounting command: %s\nMounting arguments: %s\nOutput: %s",
+			err, mountCmd, args, string(output))
+	}
+	return err
+}
+
+// detectSystemd returns true if OS runs with systemd as init. When not sure
+// (permission errors, ...), it returns false.
+// There may be different ways how to detect systemd, this one makes sure that
+// systemd-runs (needed by Mount()) works.
+func detectSystemd() bool {
+	if _, err := exec.LookPath("systemd-run"); err != nil {
+		klog.V(2).Infof("Detected OS without systemd")
+		return false
+	}
+	// Try to run systemd-run --scope /bin/true, that should be enough
+	// to make sure that systemd is really running and not just installed,
+	// which happens when running in a container with a systemd-based image
+	// but with different pid 1.
+	cmd := exec.Command("systemd-run", "--description=Kubernetes systemd probe", "--scope", "true")
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		klog.V(2).Infof("Cannot run systemd-run, assuming non-systemd OS")
+		klog.V(4).Infof("systemd-run failed with: %v", err)
+		klog.V(4).Infof("systemd-run output: %s", string(output))
+		return false
+	}
+	klog.V(2).Infof("Detected OS with systemd")
+	return true
+}
+
+// MakeMountArgs makes the arguments to the mount(8) command.
+// Implementation is shared with NsEnterMounter
+func MakeMountArgs(source, target, fstype string, options []string) []string {
+	// Build mount command as follows:
+	//   mount [-t $fstype] [-o $options] [$source] $target
+	mountArgs := []string{}
+	if len(fstype) > 0 {
+		mountArgs = append(mountArgs, "-t", fstype)
+	}
+	if len(options) > 0 {
+		mountArgs = append(mountArgs, "-o", strings.Join(options, ","))
+	}
+	if len(source) > 0 {
+		mountArgs = append(mountArgs, source)
+	}
+	mountArgs = append(mountArgs, target)
+
+	return mountArgs
+}
+
+// AddSystemdScope adds "system-run --scope" to given command line
+// implementation is shared with NsEnterMounter
+func AddSystemdScope(systemdRunPath, mountName, command string, args []string) (string, []string) {
+	descriptionArg := fmt.Sprintf("--description=Kubernetes transient mount for %s", mountName)
+	systemdRunArgs := []string{descriptionArg, "--scope", "--", command}
+	return systemdRunPath, append(systemdRunArgs, args...)
+}
+
+// Unmount unmounts the target.
+func (mounter *Mounter) Unmount(target string) error {
+	klog.V(4).Infof("Unmounting %s", target)
+	command := exec.Command("umount", target)
+	output, err := command.CombinedOutput()
+	if err != nil {
+		return fmt.Errorf("unmount failed: %v\nUnmounting arguments: %s\nOutput: %s", err, target, string(output))
+	}
+	return nil
+}
+
+// List returns a list of all mounted filesystems.
+func (*Mounter) List() ([]MountPoint, error) {
+	return ListProcMounts(procMountsPath)
+}
+
+// IsLikelyNotMountPoint determines if a directory is not a mountpoint.
+// It is fast but not necessarily ALWAYS correct. If the path is in fact
+// a bind mount from one part of a mount to another it will not be detected.
+// It also can not distinguish between mountpoints and symbolic links.
+// mkdir /tmp/a /tmp/b; mount --bind /tmp/a /tmp/b; IsLikelyNotMountPoint("/tmp/b")
+// will return true. When in fact /tmp/b is a mount point. If this situation
+// is of interest to you, don't use this function...
+func (mounter *Mounter) IsLikelyNotMountPoint(file string) (bool, error) {
+	stat, err := os.Stat(file)
+	if err != nil {
+		return true, err
+	}
+	rootStat, err := os.Stat(filepath.Dir(strings.TrimSuffix(file, "/")))
+	if err != nil {
+		return true, err
+	}
+	// If the directory has a different device as parent, then it is a mountpoint.
+	if stat.Sys().(*syscall.Stat_t).Dev != rootStat.Sys().(*syscall.Stat_t).Dev {
+		return false, nil
+	}
+
+	return true, nil
+}
+
+// GetMountRefs finds all mount references to pathname, returns a
+// list of paths. Path could be a mountpoint or a normal
+// directory (for bind mount).
+func (mounter *Mounter) GetMountRefs(pathname string) ([]string, error) {
+	pathExists, pathErr := PathExists(pathname)
+	if !pathExists {
+		return []string{}, nil
+	} else if IsCorruptedMnt(pathErr) {
+		klog.Warningf("GetMountRefs found corrupted mount at %s, treating as unmounted path", pathname)
+		return []string{}, nil
+	} else if pathErr != nil {
+		return nil, fmt.Errorf("error checking path %s: %v", pathname, pathErr)
+	}
+	realpath, err := filepath.EvalSymlinks(pathname)
+	if err != nil {
+		return nil, err
+	}
+	return SearchMountPoints(realpath, procMountInfoPath)
+}
+
+// formatAndMount uses unix utils to format and mount the given disk
+func (mounter *SafeFormatAndMount) formatAndMount(source string, target string, fstype string, options []string) error {
+	readOnly := false
+	for _, option := range options {
+		if option == "ro" {
+			readOnly = true
+			break
+		}
+	}
+
+	options = append(options, "defaults")
+
+	if !readOnly {
+		// Run fsck on the disk to fix repairable issues, only do this for volumes requested as rw.
+		klog.V(4).Infof("Checking for issues with fsck on disk: %s", source)
+		args := []string{"-a", source}
+		out, err := mounter.Exec.Command("fsck", args...).CombinedOutput()
+		if err != nil {
+			ee, isExitError := err.(utilexec.ExitError)
+			switch {
+			case err == utilexec.ErrExecutableNotFound:
+				klog.Warningf("'fsck' not found on system; continuing mount without running 'fsck'.")
+			case isExitError && ee.ExitStatus() == fsckErrorsCorrected:
+				klog.Infof("Device %s has errors which were corrected by fsck.", source)
+			case isExitError && ee.ExitStatus() == fsckErrorsUncorrected:
+				return fmt.Errorf("'fsck' found errors on device %s but could not correct them: %s", source, string(out))
+			case isExitError && ee.ExitStatus() > fsckErrorsUncorrected:
+				klog.Infof("`fsck` error %s", string(out))
+			}
+		}
+	}
+
+	// Try to mount the disk
+	klog.V(4).Infof("Attempting to mount disk: %s %s %s", fstype, source, target)
+	mountErr := mounter.Interface.Mount(source, target, fstype, options)
+	if mountErr != nil {
+		// Mount failed. This indicates either that the disk is unformatted or
+		// it contains an unexpected filesystem.
+		existingFormat, err := mounter.GetDiskFormat(source)
+		if err != nil {
+			return err
+		}
+		if existingFormat == "" {
+			if readOnly {
+				// Don't attempt to format if mounting as readonly, return an error to reflect this.
+				return errors.New("failed to mount unformatted volume as read only")
+			}
+
+			// Disk is unformatted so format it.
+			args := []string{source}
+			// Use 'ext4' as the default
+			if len(fstype) == 0 {
+				fstype = "ext4"
+			}
+
+			if fstype == "ext4" || fstype == "ext3" {
+				args = []string{
+					"-F",  // Force flag
+					"-m0", // Zero blocks reserved for super-user
+					source,
+				}
+			}
+			klog.Infof("Disk %q appears to be unformatted, attempting to format as type: %q with options: %v", source, fstype, args)
+			_, err := mounter.Exec.Command("mkfs."+fstype, args...).CombinedOutput()
+			if err == nil {
+				// the disk has been formatted successfully try to mount it again.
+				klog.Infof("Disk successfully formatted (mkfs): %s - %s %s", fstype, source, target)
+				return mounter.Interface.Mount(source, target, fstype, options)
+			}
+			klog.Errorf("format of disk %q failed: type:(%q) target:(%q) options:(%q)error:(%v)", source, fstype, target, options, err)
+			return err
+		}
+		// Disk is already formatted and failed to mount
+		if len(fstype) == 0 || fstype == existingFormat {
+			// This is mount error
+			return mountErr
+		}
+		// Block device is formatted with unexpected filesystem, let the user know
+		return fmt.Errorf("failed to mount the volume as %q, it already contains %s. Mount error: %v", fstype, existingFormat, mountErr)
+	}
+	return mountErr
+}
+
+// GetDiskFormat uses 'blkid' to see if the given disk is unformatted
+func (mounter *SafeFormatAndMount) GetDiskFormat(disk string) (string, error) {
+	args := []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", disk}
+	klog.V(4).Infof("Attempting to determine if disk %q is formatted using blkid with args: (%v)", disk, args)
+	dataOut, err := mounter.Exec.Command("blkid", args...).CombinedOutput()
+	output := string(dataOut)
+	klog.V(4).Infof("Output: %q, err: %v", output, err)
+
+	if err != nil {
+		if exit, ok := err.(utilexec.ExitError); ok {
+			if exit.ExitStatus() == 2 {
+				// Disk device is unformatted.
+				// For `blkid`, if the specified token (TYPE/PTTYPE, etc) was
+				// not found, or no (specified) devices could be identified, an
+				// exit code of 2 is returned.
+				return "", nil
+			}
+		}
+		klog.Errorf("Could not determine if disk %q is formatted (%v)", disk, err)
+		return "", err
+	}
+
+	var fstype, pttype string
+
+	lines := strings.Split(output, "\n")
+	for _, l := range lines {
+		if len(l) <= 0 {
+			// Ignore empty line.
+			continue
+		}
+		cs := strings.Split(l, "=")
+		if len(cs) != 2 {
+			return "", fmt.Errorf("blkid returns invalid output: %s", output)
+		}
+		// TYPE is filesystem type, and PTTYPE is partition table type, according
+		// to https://www.kernel.org/pub/linux/utils/util-linux/v2.21/libblkid-docs/.
+		if cs[0] == "TYPE" {
+			fstype = cs[1]
+		} else if cs[0] == "PTTYPE" {
+			pttype = cs[1]
+		}
+	}
+
+	if len(pttype) > 0 {
+		klog.V(4).Infof("Disk %s detected partition table type: %s", disk, pttype)
+		// Returns a special non-empty string as filesystem type, then kubelet
+		// will not format it.
+		return "unknown data, probably partitions", nil
+	}
+
+	return fstype, nil
+}
+
+// ListProcMounts is shared with NsEnterMounter
+func ListProcMounts(mountFilePath string) ([]MountPoint, error) {
+	content, err := utilio.ConsistentRead(mountFilePath, maxListTries)
+	if err != nil {
+		return nil, err
+	}
+	return parseProcMounts(content)
+}
+
+func parseProcMounts(content []byte) ([]MountPoint, error) {
+	out := []MountPoint{}
+	lines := strings.Split(string(content), "\n")
+	for _, line := range lines {
+		if line == "" {
+			// the last split() item is empty string following the last \n
+			continue
+		}
+		fields := strings.Fields(line)
+		if len(fields) != expectedNumFieldsPerLine {
+			return nil, fmt.Errorf("wrong number of fields (expected %d, got %d): %s", expectedNumFieldsPerLine, len(fields), line)
+		}
+
+		mp := MountPoint{
+			Device: fields[0],
+			Path:   fields[1],
+			Type:   fields[2],
+			Opts:   strings.Split(fields[3], ","),
+		}
+
+		freq, err := strconv.Atoi(fields[4])
+		if err != nil {
+			return nil, err
+		}
+		mp.Freq = freq
+
+		pass, err := strconv.Atoi(fields[5])
+		if err != nil {
+			return nil, err
+		}
+		mp.Pass = pass
+
+		out = append(out, mp)
+	}
+	return out, nil
+}
+
+// SearchMountPoints finds all mount references to the source, returns a list of
+// mountpoints.
+// The source can be a mount point or a normal directory (bind mount). We
+// didn't support device because there is no use case by now.
+// Some filesystems may share a source name, e.g. tmpfs. And for bind mounting,
+// it's possible to mount a non-root path of a filesystem, so we need to use
+// root path and major:minor to represent mount source uniquely.
+// This implementation is shared between Linux and NsEnterMounter
+func SearchMountPoints(hostSource, mountInfoPath string) ([]string, error) {
+	mis, err := ParseMountInfo(mountInfoPath)
+	if err != nil {
+		return nil, err
+	}
+
+	mountID := 0
+	rootPath := ""
+	majorMinor := ""
+
+	// Finding the underlying root path and major:minor if possible.
+	// We need search in backward order because it's possible for later mounts
+	// to overlap earlier mounts.
+	for i := len(mis) - 1; i >= 0; i-- {
+		if hostSource == mis[i].MountPoint || PathWithinBase(hostSource, mis[i].MountPoint) {
+			// If it's a mount point or path under a mount point.
+			mountID = mis[i].ID
+			rootPath = filepath.Join(mis[i].Root, strings.TrimPrefix(hostSource, mis[i].MountPoint))
+			majorMinor = mis[i].MajorMinor
+			break
+		}
+	}
+
+	if rootPath == "" || majorMinor == "" {
+		return nil, fmt.Errorf("failed to get root path and major:minor for %s", hostSource)
+	}
+
+	var refs []string
+	for i := range mis {
+		if mis[i].ID == mountID {
+			// Ignore mount entry for mount source itself.
+			continue
+		}
+		if mis[i].Root == rootPath && mis[i].MajorMinor == majorMinor {
+			refs = append(refs, mis[i].MountPoint)
+		}
+	}
+
+	return refs, nil
+}

mount_linux_test.go

@@ -0,0 +1,439 @@
+// +build linux
+
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"io/ioutil"
+	"os"
+	"reflect"
+	"testing"
+)
+
+func TestReadProcMountsFrom(t *testing.T) {
+	successCase :=
+		`/dev/0 /path/to/0 type0 flags 0 0
+/dev/1    /path/to/1   type1	flags 1 1
+/dev/2 /path/to/2 type2 flags,1,2=3 2 2
+`
+	// NOTE: readProcMountsFrom has been updated to using fnv.New32a()
+	mounts, err := parseProcMounts([]byte(successCase))
+	if err != nil {
+		t.Errorf("expected success, got %v", err)
+	}
+	if len(mounts) != 3 {
+		t.Fatalf("expected 3 mounts, got %d", len(mounts))
+	}
+	mp := MountPoint{"/dev/0", "/path/to/0", "type0", []string{"flags"}, 0, 0}
+	if !mountPointsEqual(&mounts[0], &mp) {
+		t.Errorf("got unexpected MountPoint[0]: %#v", mounts[0])
+	}
+	mp = MountPoint{"/dev/1", "/path/to/1", "type1", []string{"flags"}, 1, 1}
+	if !mountPointsEqual(&mounts[1], &mp) {
+		t.Errorf("got unexpected MountPoint[1]: %#v", mounts[1])
+	}
+	mp = MountPoint{"/dev/2", "/path/to/2", "type2", []string{"flags", "1", "2=3"}, 2, 2}
+	if !mountPointsEqual(&mounts[2], &mp) {
+		t.Errorf("got unexpected MountPoint[2]: %#v", mounts[2])
+	}
+
+	errorCases := []string{
+		"/dev/0 /path/to/mount\n",
+		"/dev/1 /path/to/mount type flags a 0\n",
+		"/dev/2 /path/to/mount type flags 0 b\n",
+	}
+	for _, ec := range errorCases {
+		_, err := parseProcMounts([]byte(ec))
+		if err == nil {
+			t.Errorf("expected error")
+		}
+	}
+}
+
+func mountPointsEqual(a, b *MountPoint) bool {
+	if a.Device != b.Device || a.Path != b.Path || a.Type != b.Type || !reflect.DeepEqual(a.Opts, b.Opts) || a.Pass != b.Pass || a.Freq != b.Freq {
+		return false
+	}
+	return true
+}
+
+func TestGetMountRefs(t *testing.T) {
+	fm := NewFakeMounter(
+		[]MountPoint{
+			{Device: "/dev/sdb", Path: "/var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/gce-pd"},
+			{Device: "/dev/sdb", Path: "/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd-in-pod"},
+			{Device: "/dev/sdc", Path: "/var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/gce-pd2"},
+			{Device: "/dev/sdc", Path: "/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd2-in-pod1"},
+			{Device: "/dev/sdc", Path: "/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd2-in-pod2"},
+		})
+
+	tests := []struct {
+		mountPath    string
+		expectedRefs []string
+	}{
+		{
+			"/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd-in-pod",
+			[]string{
+				"/var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/gce-pd",
+			},
+		},
+		{
+			"/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd2-in-pod1",
+			[]string{
+				"/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd2-in-pod2",
+				"/var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/gce-pd2",
+			},
+		},
+		{
+			"/var/fake/directory/that/doesnt/exist",
+			[]string{},
+		},
+	}
+
+	for i, test := range tests {
+		if refs, err := fm.GetMountRefs(test.mountPath); err != nil || !setEquivalent(test.expectedRefs, refs) {
+			t.Errorf("%d. getMountRefs(%q) = %v, %v; expected %v, nil", i, test.mountPath, refs, err, test.expectedRefs)
+		}
+	}
+}
+
+func setEquivalent(set1, set2 []string) bool {
+	map1 := make(map[string]bool)
+	map2 := make(map[string]bool)
+	for _, s := range set1 {
+		map1[s] = true
+	}
+	for _, s := range set2 {
+		map2[s] = true
+	}
+
+	for s := range map1 {
+		if !map2[s] {
+			return false
+		}
+	}
+	for s := range map2 {
+		if !map1[s] {
+			return false
+		}
+	}
+	return true
+}
+
+func TestGetDeviceNameFromMount(t *testing.T) {
+	fm := NewFakeMounter(
+		[]MountPoint{
+			{Device: "/dev/disk/by-path/prefix-lun-1",
+				Path: "/mnt/111"},
+			{Device: "/dev/disk/by-path/prefix-lun-1",
+				Path: "/mnt/222"},
+		})
+
+	tests := []struct {
+		mountPath      string
+		expectedDevice string
+		expectedRefs   int
+	}{
+		{
+			"/mnt/222",
+			"/dev/disk/by-path/prefix-lun-1",
+			2,
+		},
+	}
+
+	for i, test := range tests {
+		if device, refs, err := GetDeviceNameFromMount(fm, test.mountPath); err != nil || test.expectedRefs != refs || test.expectedDevice != device {
+			t.Errorf("%d. GetDeviceNameFromMount(%s) = (%s, %d), %v; expected (%s,%d), nil", i, test.mountPath, device, refs, err, test.expectedDevice, test.expectedRefs)
+		}
+	}
+}
+
+func TestGetMountRefsByDev(t *testing.T) {
+	fm := NewFakeMounter(
+		[]MountPoint{
+			{Device: "/dev/sdb", Path: "/var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/gce-pd"},
+			{Device: "/dev/sdb", Path: "/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd-in-pod"},
+			{Device: "/dev/sdc", Path: "/var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/gce-pd2"},
+			{Device: "/dev/sdc", Path: "/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd2-in-pod1"},
+			{Device: "/dev/sdc", Path: "/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd2-in-pod2"},
+		})
+
+	tests := []struct {
+		mountPath    string
+		expectedRefs []string
+	}{
+		{
+			"/var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/gce-pd",
+			[]string{
+				"/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd-in-pod",
+			},
+		},
+		{
+			"/var/lib/kubelet/plugins/kubernetes.io/gce-pd/mounts/gce-pd2",
+			[]string{
+				"/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd2-in-pod1",
+				"/var/lib/kubelet/pods/some-pod/volumes/kubernetes.io~gce-pd/gce-pd2-in-pod2",
+			},
+		},
+	}
+
+	for i, test := range tests {
+
+		if refs, err := getMountRefsByDev(fm, test.mountPath); err != nil || !setEquivalent(test.expectedRefs, refs) {
+			t.Errorf("%d. getMountRefsByDev(%q) = %v, %v; expected %v, nil", i, test.mountPath, refs, err, test.expectedRefs)
+		}
+	}
+}
+
+func TestPathWithinBase(t *testing.T) {
+	tests := []struct {
+		name     string
+		fullPath string
+		basePath string
+		expected bool
+	}{
+		{
+			name:     "good subpath",
+			fullPath: "/a/b/c",
+			basePath: "/a",
+			expected: true,
+		},
+		{
+			name:     "good subpath 2",
+			fullPath: "/a/b/c",
+			basePath: "/a/b",
+			expected: true,
+		},
+		{
+			name:     "good subpath end slash",
+			fullPath: "/a/b/c/",
+			basePath: "/a/b",
+			expected: true,
+		},
+		{
+			name:     "good subpath backticks",
+			fullPath: "/a/b/../c",
+			basePath: "/a",
+			expected: true,
+		},
+		{
+			name:     "good subpath equal",
+			fullPath: "/a/b/c",
+			basePath: "/a/b/c",
+			expected: true,
+		},
+		{
+			name:     "good subpath equal 2",
+			fullPath: "/a/b/c/",
+			basePath: "/a/b/c",
+			expected: true,
+		},
+		{
+			name:     "good subpath root",
+			fullPath: "/a",
+			basePath: "/",
+			expected: true,
+		},
+		{
+			name:     "bad subpath parent",
+			fullPath: "/a/b/c",
+			basePath: "/a/b/c/d",
+			expected: false,
+		},
+		{
+			name:     "bad subpath outside",
+			fullPath: "/b/c",
+			basePath: "/a/b/c",
+			expected: false,
+		},
+		{
+			name:     "bad subpath prefix",
+			fullPath: "/a/b/cd",
+			basePath: "/a/b/c",
+			expected: false,
+		},
+		{
+			name:     "bad subpath backticks",
+			fullPath: "/a/../b",
+			basePath: "/a",
+			expected: false,
+		},
+		{
+			name:     "configmap subpath",
+			fullPath: "/var/lib/kubelet/pods/uuid/volumes/kubernetes.io~configmap/config/..timestamp/file.txt",
+			basePath: "/var/lib/kubelet/pods/uuid/volumes/kubernetes.io~configmap/config",
+			expected: true,
+		},
+	}
+	for _, test := range tests {
+		if PathWithinBase(test.fullPath, test.basePath) != test.expected {
+			t.Errorf("test %q failed: expected %v", test.name, test.expected)
+		}
+
+	}
+}
+
+func TestSearchMountPoints(t *testing.T) {
+	base := `
+19 25 0:18 / /sys rw,nosuid,nodev,noexec,relatime shared:7 - sysfs sysfs rw
+20 25 0:4 / /proc rw,nosuid,nodev,noexec,relatime shared:12 - proc proc rw
+21 25 0:6 / /dev rw,nosuid,relatime shared:2 - devtmpfs udev rw,size=4058156k,nr_inodes=1014539,mode=755
+22 21 0:14 / /dev/pts rw,nosuid,noexec,relatime shared:3 - devpts devpts rw,gid=5,mode=620,ptmxmode=000
+23 25 0:19 / /run rw,nosuid,noexec,relatime shared:5 - tmpfs tmpfs rw,size=815692k,mode=755
+25 0 252:0 / / rw,relatime shared:1 - ext4 /dev/mapper/ubuntu--vg-root rw,errors=remount-ro,data=ordered
+26 19 0:12 / /sys/kernel/security rw,nosuid,nodev,noexec,relatime shared:8 - securityfs securityfs rw
+27 21 0:21 / /dev/shm rw,nosuid,nodev shared:4 - tmpfs tmpfs rw
+28 23 0:22 / /run/lock rw,nosuid,nodev,noexec,relatime shared:6 - tmpfs tmpfs rw,size=5120k
+29 19 0:23 / /sys/fs/cgroup ro,nosuid,nodev,noexec shared:9 - tmpfs tmpfs ro,mode=755
+30 29 0:24 / /sys/fs/cgroup/systemd rw,nosuid,nodev,noexec,relatime shared:10 - cgroup cgroup rw,xattr,release_agent=/lib/systemd/systemd-cgroups-agent,name=systemd
+31 19 0:25 / /sys/fs/pstore rw,nosuid,nodev,noexec,relatime shared:11 - pstore pstore rw
+32 29 0:26 / /sys/fs/cgroup/devices rw,nosuid,nodev,noexec,relatime shared:13 - cgroup cgroup rw,devices
+33 29 0:27 / /sys/fs/cgroup/freezer rw,nosuid,nodev,noexec,relatime shared:14 - cgroup cgroup rw,freezer
+34 29 0:28 / /sys/fs/cgroup/pids rw,nosuid,nodev,noexec,relatime shared:15 - cgroup cgroup rw,pids
+35 29 0:29 / /sys/fs/cgroup/blkio rw,nosuid,nodev,noexec,relatime shared:16 - cgroup cgroup rw,blkio
+36 29 0:30 / /sys/fs/cgroup/memory rw,nosuid,nodev,noexec,relatime shared:17 - cgroup cgroup rw,memory
+37 29 0:31 / /sys/fs/cgroup/perf_event rw,nosuid,nodev,noexec,relatime shared:18 - cgroup cgroup rw,perf_event
+38 29 0:32 / /sys/fs/cgroup/hugetlb rw,nosuid,nodev,noexec,relatime shared:19 - cgroup cgroup rw,hugetlb
+39 29 0:33 / /sys/fs/cgroup/cpu,cpuacct rw,nosuid,nodev,noexec,relatime shared:20 - cgroup cgroup rw,cpu,cpuacct
+40 29 0:34 / /sys/fs/cgroup/cpuset rw,nosuid,nodev,noexec,relatime shared:21 - cgroup cgroup rw,cpuset
+41 29 0:35 / /sys/fs/cgroup/net_cls,net_prio rw,nosuid,nodev,noexec,relatime shared:22 - cgroup cgroup rw,net_cls,net_prio
+58 25 7:1 / /mnt/disks/blkvol1 rw,relatime shared:38 - ext4 /dev/loop1 rw,data=ordere
+`
+
+	testcases := []struct {
+		name         string
+		source       string
+		mountInfos   string
+		expectedRefs []string
+		expectedErr  error
+	}{
+		{
+			"dir",
+			"/mnt/disks/vol1",
+			base,
+			nil,
+			nil,
+		},
+		{
+			"dir-used",
+			"/mnt/disks/vol1",
+			base + `
+56 25 252:0 /mnt/disks/vol1 /var/lib/kubelet/pods/1890aef5-5a60-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test rw,relatime shared:1 - ext4 /dev/mapper/ubuntu--vg-root rw,errors=remount-ro,data=ordered
+57 25 0:45 / /mnt/disks/vol rw,relatime shared:36 - tmpfs tmpfs rw
+`,
+			[]string{"/var/lib/kubelet/pods/1890aef5-5a60-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test"},
+			nil,
+		},
+		{
+			"tmpfs-vol",
+			"/mnt/disks/vol1",
+			base + `120 25 0:76 / /mnt/disks/vol1 rw,relatime shared:41 - tmpfs vol1 rw,size=10000k
+`,
+			nil,
+			nil,
+		},
+		{
+			"tmpfs-vol-used-by-two-pods",
+			"/mnt/disks/vol1",
+			base + `120 25 0:76 / /mnt/disks/vol1 rw,relatime shared:41 - tmpfs vol1 rw,size=10000k
+196 25 0:76 / /var/lib/kubelet/pods/ade3ac21-5a5b-11e8-8559-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-8f263585 rw,relatime shared:41 - tmpfs vol1 rw,size=10000k
+228 25 0:76 / /var/lib/kubelet/pods/ac60532d-5a5b-11e8-8559-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-8f263585 rw,relatime shared:41 - tmpfs vol1 rw,size=10000k
+`,
+			[]string{
+				"/var/lib/kubelet/pods/ade3ac21-5a5b-11e8-8559-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-8f263585",
+				"/var/lib/kubelet/pods/ac60532d-5a5b-11e8-8559-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-8f263585",
+			},
+			nil,
+		},
+		{
+			"tmpfs-subdir-used-indirectly-via-bindmount-dir-by-one-pod",
+			"/mnt/vol1/foo",
+			base + `177 25 0:46 / /mnt/data rw,relatime shared:37 - tmpfs data rw
+190 25 0:46 /vol1 /mnt/vol1 rw,relatime shared:37 - tmpfs data rw
+191 25 0:46 /vol2 /mnt/vol2 rw,relatime shared:37 - tmpfs data rw
+62 25 0:46 /vol1/foo /var/lib/kubelet/pods/e25f2f01-5b06-11e8-8694-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test rw,relatime shared:37 - tmpfs data rw
+`,
+			[]string{"/var/lib/kubelet/pods/e25f2f01-5b06-11e8-8694-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test"},
+			nil,
+		},
+		{
+			"dir-bindmounted",
+			"/mnt/disks/vol2",
+			base + `342 25 252:0 /mnt/disks/vol2 /mnt/disks/vol2 rw,relatime shared:1 - ext4 /dev/mapper/ubuntu--vg-root rw,errors=remount-ro,data=ordered
+`,
+			nil,
+			nil,
+		},
+		{
+			"dir-bindmounted-used-by-one-pod",
+			"/mnt/disks/vol2",
+			base + `342 25 252:0 /mnt/disks/vol2 /mnt/disks/vol2 rw,relatime shared:1 - ext4 /dev/mapper/ubuntu--vg-root rw,errors=remount-ro,data=ordered
+77 25 252:0 /mnt/disks/vol2 /var/lib/kubelet/pods/f30dc360-5a5d-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-1fb30a1c rw,relatime shared:1 - ext4 /dev/mapper/ubuntu--vg-root rw,errors=remount-ro,data=ordered
+`,
+			[]string{"/var/lib/kubelet/pods/f30dc360-5a5d-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-1fb30a1c"},
+			nil,
+		},
+		{
+			"blockfs",
+			"/mnt/disks/blkvol1",
+			base + `58 25 7:1 / /mnt/disks/blkvol1 rw,relatime shared:38 - ext4 /dev/loop1 rw,data=ordered
+`,
+			nil,
+			nil,
+		},
+		{
+			"blockfs-used-by-one-pod",
+			"/mnt/disks/blkvol1",
+			base + `58 25 7:1 / /mnt/disks/blkvol1 rw,relatime shared:38 - ext4 /dev/loop1 rw,data=ordered
+62 25 7:1 / /var/lib/kubelet/pods/f19fe4e2-5a63-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test rw,relatime shared:38 - ext4 /dev/loop1 rw,data=ordered
+`,
+			[]string{"/var/lib/kubelet/pods/f19fe4e2-5a63-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test"},
+			nil,
+		},
+		{
+			"blockfs-used-by-two-pods",
+			"/mnt/disks/blkvol1",
+			base + `58 25 7:1 / /mnt/disks/blkvol1 rw,relatime shared:38 - ext4 /dev/loop1 rw,data=ordered
+62 25 7:1 / /var/lib/kubelet/pods/f19fe4e2-5a63-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test rw,relatime shared:38 - ext4 /dev/loop1 rw,data=ordered
+95 25 7:1 / /var/lib/kubelet/pods/4854a48b-5a64-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test rw,relatime shared:38 - ext4 /dev/loop1 rw,data=ordered
+`,
+			[]string{"/var/lib/kubelet/pods/f19fe4e2-5a63-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test",
+				"/var/lib/kubelet/pods/4854a48b-5a64-11e8-962f-000c29bb0377/volumes/kubernetes.io~local-volume/local-pv-test"},
+			nil,
+		},
+	}
+	tmpFile, err := ioutil.TempFile("", "test-get-filetype")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(tmpFile.Name())
+	defer tmpFile.Close()
+	for _, v := range testcases {
+		tmpFile.Truncate(0)
+		tmpFile.Seek(0, 0)
+		tmpFile.WriteString(v.mountInfos)
+		tmpFile.Sync()
+		refs, err := SearchMountPoints(v.source, tmpFile.Name())
+		if !reflect.DeepEqual(refs, v.expectedRefs) {
+			t.Errorf("test %q: expected Refs: %#v, got %#v", v.name, v.expectedRefs, refs)
+		}
+		if !reflect.DeepEqual(err, v.expectedErr) {
+			t.Errorf("test %q: expected err: %v, got %v", v.name, v.expectedErr, err)
+		}
+	}
+}

mount_test.go

@@ -0,0 +1,60 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"reflect"
+	"testing"
+)
+
+func TestMakeBindOpts(t *testing.T) {
+	tests := []struct {
+		mountOption         []string
+		isBind              bool
+		expectedBindOpts    []string
+		expectedRemountOpts []string
+	}{
+		{
+			[]string{"vers=2", "ro", "_netdev"},
+			false,
+			[]string{},
+			[]string{},
+		},
+		{
+
+			[]string{"bind", "vers=2", "ro", "_netdev"},
+			true,
+			[]string{"bind", "_netdev"},
+			[]string{"bind", "remount", "vers=2", "ro", "_netdev"},
+		},
+	}
+	for _, test := range tests {
+		bind, bindOpts, bindRemountOpts := MakeBindOpts(test.mountOption)
+		if bind != test.isBind {
+			t.Errorf("Expected bind to be %v but got %v", test.isBind, bind)
+		}
+		if test.isBind {
+			if !reflect.DeepEqual(test.expectedBindOpts, bindOpts) {
+				t.Errorf("Expected bind mount options to be %+v got %+v", test.expectedBindOpts, bindOpts)
+			}
+			if !reflect.DeepEqual(test.expectedRemountOpts, bindRemountOpts) {
+				t.Errorf("Expected remount options to be %+v got %+v", test.expectedRemountOpts, bindRemountOpts)
+			}
+		}
+
+	}
+}

mount_unsupported.go

@@ -0,0 +1,72 @@
+// +build !linux,!windows
+
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"errors"
+)
+
+// Mounter implements mount.Interface for unsupported platforms
+type Mounter struct {
+	mounterPath string
+}
+
+var errUnsupported = errors.New("util/mount on this platform is not supported")
+
+// New returns a mount.Interface for the current system.
+// It provides options to override the default mounter behavior.
+// mounterPath allows using an alternative to `/bin/mount` for mounting.
+func New(mounterPath string) Interface {
+	return &Mounter{
+		mounterPath: mounterPath,
+	}
+}
+
+// Mount always returns an error on unsupported platforms
+func (mounter *Mounter) Mount(source string, target string, fstype string, options []string) error {
+	return errUnsupported
+}
+
+// Unmount always returns an error on unsupported platforms
+func (mounter *Mounter) Unmount(target string) error {
+	return errUnsupported
+}
+
+// List always returns an error on unsupported platforms
+func (mounter *Mounter) List() ([]MountPoint, error) {
+	return []MountPoint{}, errUnsupported
+}
+
+// IsLikelyNotMountPoint always returns an error on unsupported platforms
+func (mounter *Mounter) IsLikelyNotMountPoint(file string) (bool, error) {
+	return true, errUnsupported
+}
+
+// GetMountRefs always returns an error on unsupported platforms
+func (mounter *Mounter) GetMountRefs(pathname string) ([]string, error) {
+	return nil, errUnsupported
+}
+
+func (mounter *SafeFormatAndMount) formatAndMount(source string, target string, fstype string, options []string) error {
+	return mounter.Interface.Mount(source, target, fstype, options)
+}
+
+func (mounter *SafeFormatAndMount) diskLooksUnformatted(disk string) (bool, error) {
+	return true, errUnsupported
+}

mount_windows.go

@@ -0,0 +1,280 @@
+// +build windows
+
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+
+	"k8s.io/klog"
+	utilexec "k8s.io/utils/exec"
+	"k8s.io/utils/keymutex"
+	utilpath "k8s.io/utils/path"
+)
+
+// Mounter provides the default implementation of mount.Interface
+// for the windows platform.  This implementation assumes that the
+// kubelet is running in the host's root mount namespace.
+type Mounter struct {
+	mounterPath string
+}
+
+// New returns a mount.Interface for the current system.
+// It provides options to override the default mounter behavior.
+// mounterPath allows using an alternative to `/bin/mount` for mounting.
+func New(mounterPath string) Interface {
+	return &Mounter{
+		mounterPath: mounterPath,
+	}
+}
+
+// acquire lock for smb mount
+var getSMBMountMutex = keymutex.NewHashed(0)
+
+// Mount : mounts source to target with given options.
+// currently only supports cifs(smb), bind mount(for disk)
+func (mounter *Mounter) Mount(source string, target string, fstype string, options []string) error {
+	target = NormalizeWindowsPath(target)
+
+	if source == "tmpfs" {
+		klog.V(3).Infof("mounting source (%q), target (%q), with options (%q)", source, target, options)
+		return os.MkdirAll(target, 0755)
+	}
+
+	parentDir := filepath.Dir(target)
+	if err := os.MkdirAll(parentDir, 0755); err != nil {
+		return err
+	}
+
+	klog.V(4).Infof("mount options(%q) source:%q, target:%q, fstype:%q, begin to mount",
+		options, source, target, fstype)
+	bindSource := source
+
+	// tell it's going to mount azure disk or azure file according to options
+	if bind, _, _ := MakeBindOpts(options); bind {
+		// mount azure disk
+		bindSource = NormalizeWindowsPath(source)
+	} else {
+		if len(options) < 2 {
+			klog.Warningf("mount options(%q) command number(%d) less than 2, source:%q, target:%q, skip mounting",
+				options, len(options), source, target)
+			return nil
+		}
+
+		// currently only cifs mount is supported
+		if strings.ToLower(fstype) != "cifs" {
+			return fmt.Errorf("only cifs mount is supported now, fstype: %q, mounting source (%q), target (%q), with options (%q)", fstype, source, target, options)
+		}
+
+		// lock smb mount for the same source
+		getSMBMountMutex.LockKey(source)
+		defer getSMBMountMutex.UnlockKey(source)
+
+		if output, err := newSMBMapping(options[0], options[1], source); err != nil {
+			if isSMBMappingExist(source) {
+				klog.V(2).Infof("SMB Mapping(%s) already exists, now begin to remove and remount", source)
+				if output, err := removeSMBMapping(source); err != nil {
+					return fmt.Errorf("Remove-SmbGlobalMapping failed: %v, output: %q", err, output)
+				}
+				if output, err := newSMBMapping(options[0], options[1], source); err != nil {
+					return fmt.Errorf("New-SmbGlobalMapping remount failed: %v, output: %q", err, output)
+				}
+			} else {
+				return fmt.Errorf("New-SmbGlobalMapping failed: %v, output: %q", err, output)
+			}
+		}
+	}
+
+	if output, err := exec.Command("cmd", "/c", "mklink", "/D", target, bindSource).CombinedOutput(); err != nil {
+		klog.Errorf("mklink failed: %v, source(%q) target(%q) output: %q", err, bindSource, target, string(output))
+		return err
+	}
+
+	return nil
+}
+
+// do the SMB mount with username, password, remotepath
+// return (output, error)
+func newSMBMapping(username, password, remotepath string) (string, error) {
+	if username == "" || password == "" || remotepath == "" {
+		return "", fmt.Errorf("invalid parameter(username: %s, password: %s, remoteapth: %s)", username, password, remotepath)
+	}
+
+	// use PowerShell Environment Variables to store user input string to prevent command line injection
+	// https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_environment_variables?view=powershell-5.1
+	cmdLine := `$PWord = ConvertTo-SecureString -String $Env:smbpassword -AsPlainText -Force` +
+		`;$Credential = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $Env:smbuser, $PWord` +
+		`;New-SmbGlobalMapping -RemotePath $Env:smbremotepath -Credential $Credential`
+	cmd := exec.Command("powershell", "/c", cmdLine)
+	cmd.Env = append(os.Environ(),
+		fmt.Sprintf("smbuser=%s", username),
+		fmt.Sprintf("smbpassword=%s", password),
+		fmt.Sprintf("smbremotepath=%s", remotepath))
+
+	output, err := cmd.CombinedOutput()
+	return string(output), err
+}
+
+// check whether remotepath is already mounted
+func isSMBMappingExist(remotepath string) bool {
+	cmd := exec.Command("powershell", "/c", `Get-SmbGlobalMapping -RemotePath $Env:smbremotepath`)
+	cmd.Env = append(os.Environ(), fmt.Sprintf("smbremotepath=%s", remotepath))
+	_, err := cmd.CombinedOutput()
+	return err == nil
+}
+
+// remove SMB mapping
+func removeSMBMapping(remotepath string) (string, error) {
+	cmd := exec.Command("powershell", "/c", `Remove-SmbGlobalMapping -RemotePath $Env:smbremotepath -Force`)
+	cmd.Env = append(os.Environ(), fmt.Sprintf("smbremotepath=%s", remotepath))
+	output, err := cmd.CombinedOutput()
+	return string(output), err
+}
+
+// Unmount unmounts the target.
+func (mounter *Mounter) Unmount(target string) error {
+	klog.V(4).Infof("azureMount: Unmount target (%q)", target)
+	target = NormalizeWindowsPath(target)
+	if output, err := exec.Command("cmd", "/c", "rmdir", target).CombinedOutput(); err != nil {
+		klog.Errorf("rmdir failed: %v, output: %q", err, string(output))
+		return err
+	}
+	return nil
+}
+
+// List returns a list of all mounted filesystems. todo
+func (mounter *Mounter) List() ([]MountPoint, error) {
+	return []MountPoint{}, nil
+}
+
+// IsLikelyNotMountPoint determines if a directory is not a mountpoint.
+func (mounter *Mounter) IsLikelyNotMountPoint(file string) (bool, error) {
+	stat, err := os.Lstat(file)
+	if err != nil {
+		return true, err
+	}
+	// If current file is a symlink, then it is a mountpoint.
+	if stat.Mode()&os.ModeSymlink != 0 {
+		target, err := os.Readlink(file)
+		if err != nil {
+			return true, fmt.Errorf("readlink error: %v", err)
+		}
+		exists, err := utilpath.Exists(utilpath.CheckFollowSymlink, target)
+		if err != nil {
+			return true, err
+		}
+		return !exists, nil
+	}
+
+	return true, nil
+}
+
+// GetMountRefs : empty implementation here since there is no place to query all mount points on Windows
+func (mounter *Mounter) GetMountRefs(pathname string) ([]string, error) {
+	windowsPath := NormalizeWindowsPath(pathname)
+	pathExists, pathErr := PathExists(windowsPath)
+	if !pathExists {
+		return []string{}, nil
+	} else if IsCorruptedMnt(pathErr) {
+		klog.Warningf("GetMountRefs found corrupted mount at %s, treating as unmounted path", windowsPath)
+		return []string{}, nil
+	} else if pathErr != nil {
+		return nil, fmt.Errorf("error checking path %s: %v", windowsPath, pathErr)
+	}
+	return []string{pathname}, nil
+}
+
+func (mounter *SafeFormatAndMount) formatAndMount(source string, target string, fstype string, options []string) error {
+	// Try to mount the disk
+	klog.V(4).Infof("Attempting to formatAndMount disk: %s %s %s", fstype, source, target)
+
+	if err := ValidateDiskNumber(source); err != nil {
+		klog.Errorf("diskMount: formatAndMount failed, err: %v", err)
+		return err
+	}
+
+	if len(fstype) == 0 {
+		// Use 'NTFS' as the default
+		fstype = "NTFS"
+	}
+
+	// format disk if it is unformatted(raw)
+	cmd := fmt.Sprintf("Get-Disk -Number %s | Where partitionstyle -eq 'raw' | Initialize-Disk -PartitionStyle MBR -PassThru"+
+		" | New-Partition -AssignDriveLetter -UseMaximumSize | Format-Volume -FileSystem %s -Confirm:$false", source, fstype)
+	if output, err := mounter.Exec.Command("powershell", "/c", cmd).CombinedOutput(); err != nil {
+		return fmt.Errorf("diskMount: format disk failed, error: %v, output: %q", err, string(output))
+	}
+	klog.V(4).Infof("diskMount: Disk successfully formatted, disk: %q, fstype: %q", source, fstype)
+
+	driveLetter, err := getDriveLetterByDiskNumber(source, mounter.Exec)
+	if err != nil {
+		return err
+	}
+	driverPath := driveLetter + ":"
+	target = NormalizeWindowsPath(target)
+	klog.V(4).Infof("Attempting to formatAndMount disk: %s %s %s", fstype, driverPath, target)
+	if output, err := mounter.Exec.Command("cmd", "/c", "mklink", "/D", target, driverPath).CombinedOutput(); err != nil {
+		klog.Errorf("mklink failed: %v, output: %q", err, string(output))
+		return err
+	}
+	return nil
+}
+
+// Get drive letter according to windows disk number
+func getDriveLetterByDiskNumber(diskNum string, exec utilexec.Interface) (string, error) {
+	cmd := fmt.Sprintf("(Get-Partition -DiskNumber %s).DriveLetter", diskNum)
+	output, err := exec.Command("powershell", "/c", cmd).CombinedOutput()
+	if err != nil {
+		return "", fmt.Errorf("azureMount: Get Drive Letter failed: %v, output: %q", err, string(output))
+	}
+	if len(string(output)) < 1 {
+		return "", fmt.Errorf("azureMount: Get Drive Letter failed, output is empty")
+	}
+	return string(output)[:1], nil
+}
+
+// getAllParentLinks walks all symbolic links and return all the parent targets recursively
+func getAllParentLinks(path string) ([]string, error) {
+	const maxIter = 255
+	links := []string{}
+	for {
+		links = append(links, path)
+		if len(links) > maxIter {
+			return links, fmt.Errorf("unexpected length of parent links: %v", links)
+		}
+
+		fi, err := os.Lstat(path)
+		if err != nil {
+			return links, fmt.Errorf("Lstat: %v", err)
+		}
+		if fi.Mode()&os.ModeSymlink == 0 {
+			break
+		}
+
+		path, err = os.Readlink(path)
+		if err != nil {
+			return links, fmt.Errorf("Readlink error: %v", err)
+		}
+	}
+
+	return links, nil
+}

mount_windows_test.go

@@ -0,0 +1,333 @@
+// +build windows
+
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"k8s.io/utils/exec/testing"
+)
+
+func makeLink(link, target string) error {
+	if output, err := exec.Command("cmd", "/c", "mklink", "/D", link, target).CombinedOutput(); err != nil {
+		return fmt.Errorf("mklink failed: %v, link(%q) target(%q) output: %q", err, link, target, string(output))
+	}
+	return nil
+}
+
+func removeLink(link string) error {
+	if output, err := exec.Command("cmd", "/c", "rmdir", link).CombinedOutput(); err != nil {
+		return fmt.Errorf("rmdir failed: %v, output: %q", err, string(output))
+	}
+	return nil
+}
+
+func setEquivalent(set1, set2 []string) bool {
+	map1 := make(map[string]bool)
+	map2 := make(map[string]bool)
+	for _, s := range set1 {
+		map1[s] = true
+	}
+	for _, s := range set2 {
+		map2[s] = true
+	}
+
+	for s := range map1 {
+		if !map2[s] {
+			return false
+		}
+	}
+	for s := range map2 {
+		if !map1[s] {
+			return false
+		}
+	}
+	return true
+}
+
+// this func must run in admin mode, otherwise it will fail
+func TestGetMountRefs(t *testing.T) {
+	tests := []struct {
+		mountPath    string
+		expectedRefs []string
+	}{
+		{
+			mountPath:    `c:\windows`,
+			expectedRefs: []string{`c:\windows`},
+		},
+		{
+			mountPath:    `c:\doesnotexist`,
+			expectedRefs: []string{},
+		},
+	}
+
+	mounter := Mounter{"fake/path"}
+
+	for _, test := range tests {
+		if refs, err := mounter.GetMountRefs(test.mountPath); err != nil || !setEquivalent(test.expectedRefs, refs) {
+			t.Errorf("getMountRefs(%q) = %v, error: %v; expected %v", test.mountPath, refs, err, test.expectedRefs)
+		}
+	}
+}
+
+func TestPathWithinBase(t *testing.T) {
+	tests := []struct {
+		fullPath       string
+		basePath       string
+		expectedResult bool
+	}{
+		{
+			fullPath:       `c:\tmp\a\b\c`,
+			basePath:       `c:\tmp`,
+			expectedResult: true,
+		},
+		{
+			fullPath:       `c:\tmp1`,
+			basePath:       `c:\tmp2`,
+			expectedResult: false,
+		},
+		{
+			fullPath:       `c:\tmp`,
+			basePath:       `c:\tmp`,
+			expectedResult: true,
+		},
+		{
+			fullPath:       `c:\tmp`,
+			basePath:       `c:\tmp\a\b\c`,
+			expectedResult: false,
+		},
+		{
+			fullPath:       `c:\kubelet\pods\uuid\volumes\kubernetes.io~configmap\config\..timestamp\file.txt`,
+			basePath:       `c:\kubelet\pods\uuid\volumes\kubernetes.io~configmap\config`,
+			expectedResult: true,
+		},
+	}
+
+	for _, test := range tests {
+		result := PathWithinBase(test.fullPath, test.basePath)
+		assert.Equal(t, result, test.expectedResult, "Expect result not equal with PathWithinBase(%s, %s) return: %q, expected: %q",
+			test.fullPath, test.basePath, result, test.expectedResult)
+	}
+}
+
+func TestIsLikelyNotMountPoint(t *testing.T) {
+	mounter := Mounter{"fake/path"}
+
+	tests := []struct {
+		fileName       string
+		targetLinkName string
+		setUp          func(base, fileName, targetLinkName string) error
+		expectedResult bool
+		expectError    bool
+	}{
+		{
+			"Dir",
+			"",
+			func(base, fileName, targetLinkName string) error {
+				return os.Mkdir(filepath.Join(base, fileName), 0750)
+			},
+			true,
+			false,
+		},
+		{
+			"InvalidDir",
+			"",
+			func(base, fileName, targetLinkName string) error {
+				return nil
+			},
+			true,
+			true,
+		},
+		{
+			"ValidSymLink",
+			"targetSymLink",
+			func(base, fileName, targetLinkName string) error {
+				targeLinkPath := filepath.Join(base, targetLinkName)
+				if err := os.Mkdir(targeLinkPath, 0750); err != nil {
+					return err
+				}
+
+				filePath := filepath.Join(base, fileName)
+				if err := makeLink(filePath, targeLinkPath); err != nil {
+					return err
+				}
+				return nil
+			},
+			false,
+			false,
+		},
+		{
+			"InvalidSymLink",
+			"targetSymLink2",
+			func(base, fileName, targetLinkName string) error {
+				targeLinkPath := filepath.Join(base, targetLinkName)
+				if err := os.Mkdir(targeLinkPath, 0750); err != nil {
+					return err
+				}
+
+				filePath := filepath.Join(base, fileName)
+				if err := makeLink(filePath, targeLinkPath); err != nil {
+					return err
+				}
+				return removeLink(targeLinkPath)
+			},
+			true,
+			false,
+		},
+	}
+
+	for _, test := range tests {
+		base, err := ioutil.TempDir("", test.fileName)
+		if err != nil {
+			t.Fatalf(err.Error())
+		}
+
+		defer os.RemoveAll(base)
+
+		if err := test.setUp(base, test.fileName, test.targetLinkName); err != nil {
+			t.Fatalf("unexpected error in setUp(%s, %s): %v", test.fileName, test.targetLinkName, err)
+		}
+
+		filePath := filepath.Join(base, test.fileName)
+		result, err := mounter.IsLikelyNotMountPoint(filePath)
+		assert.Equal(t, result, test.expectedResult, "Expect result not equal with IsLikelyNotMountPoint(%s) return: %q, expected: %q",
+			filePath, result, test.expectedResult)
+
+		if test.expectError {
+			assert.NotNil(t, err, "Expect error during IsLikelyNotMountPoint(%s)", filePath)
+		} else {
+			assert.Nil(t, err, "Expect error is nil during IsLikelyNotMountPoint(%s)", filePath)
+		}
+	}
+}
+
+func TestFormatAndMount(t *testing.T) {
+	tests := []struct {
+		device       string
+		target       string
+		fstype       string
+		execScripts  []ExecArgs
+		mountOptions []string
+		expectError  bool
+	}{
+		{
+			device: "0",
+			target: "disk",
+			fstype: "NTFS",
+			execScripts: []ExecArgs{
+				{"powershell", []string{"/c", "Get-Disk", "-Number"}, "0", nil},
+				{"powershell", []string{"/c", "Get-Partition", "-DiskNumber"}, "0", nil},
+				{"cmd", []string{"/c", "mklink", "/D"}, "", nil},
+			},
+			mountOptions: []string{},
+			expectError:  false,
+		},
+		{
+			device: "0",
+			target: "disk",
+			fstype: "",
+			execScripts: []ExecArgs{
+				{"powershell", []string{"/c", "Get-Disk", "-Number"}, "0", nil},
+				{"powershell", []string{"/c", "Get-Partition", "-DiskNumber"}, "0", nil},
+				{"cmd", []string{"/c", "mklink", "/D"}, "", nil},
+			},
+			mountOptions: []string{},
+			expectError:  false,
+		},
+		{
+			device:       "invalidDevice",
+			target:       "disk",
+			fstype:       "NTFS",
+			mountOptions: []string{},
+			expectError:  true,
+		},
+	}
+
+	for _, test := range tests {
+		fakeMounter := ErrorMounter{NewFakeMounter(nil), 0, nil}
+		fakeExec := &testingexec.FakeExec{}
+		for _, script := range test.execScripts {
+			fakeCmd := &testingexec.FakeCmd{}
+			cmdAction := makeFakeCmd(fakeCmd, script.command, script.args...)
+			outputAction := makeFakeOutput(script.output, script.err)
+			fakeCmd.CombinedOutputScript = append(fakeCmd.CombinedOutputScript, outputAction)
+			fakeExec.CommandScript = append(fakeExec.CommandScript, cmdAction)
+		}
+		mounter := SafeFormatAndMount{
+			Interface: &fakeMounter,
+			Exec:      fakeExec,
+		}
+		base, err := ioutil.TempDir("", test.device)
+		if err != nil {
+			t.Fatalf(err.Error())
+		}
+		defer os.RemoveAll(base)
+
+		target := filepath.Join(base, test.target)
+		err = mounter.FormatAndMount(test.device, target, test.fstype, test.mountOptions)
+		if test.expectError {
+			assert.NotNil(t, err, "Expect error during FormatAndMount(%s, %s, %s, %v)", test.device, test.target, test.fstype, test.mountOptions)
+		} else {
+			assert.Nil(t, err, "Expect error is nil during FormatAndMount(%s, %s, %s, %v)", test.device, test.target, test.fstype, test.mountOptions)
+		}
+	}
+}
+
+func TestNewSMBMapping(t *testing.T) {
+	tests := []struct {
+		username    string
+		password    string
+		remotepath  string
+		expectError bool
+	}{
+		{
+			"",
+			"password",
+			`\\remotepath`,
+			true,
+		},
+		{
+			"username",
+			"",
+			`\\remotepath`,
+			true,
+		},
+		{
+			"username",
+			"password",
+			"",
+			true,
+		},
+	}
+
+	for _, test := range tests {
+		_, err := newSMBMapping(test.username, test.password, test.remotepath)
+		if test.expectError {
+			assert.NotNil(t, err, "Expect error during newSMBMapping(%s, %s, %s, %v)", test.username, test.password, test.remotepath)
+		} else {
+			assert.Nil(t, err, "Expect error is nil during newSMBMapping(%s, %s, %s, %v)", test.username, test.password, test.remotepath)
+		}
+	}
+}

safe_format_and_mount_test.go

@@ -0,0 +1,248 @@
+/*
+Copyright 2014 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package mount
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"runtime"
+	"strings"
+	"testing"
+
+	"k8s.io/utils/exec"
+	"k8s.io/utils/exec/testing"
+)
+
+type ErrorMounter struct {
+	*FakeMounter
+	errIndex int
+	err      []error
+}
+
+func (mounter *ErrorMounter) Mount(source string, target string, fstype string, options []string) error {
+	i := mounter.errIndex
+	mounter.errIndex++
+	if mounter.err != nil && mounter.err[i] != nil {
+		return mounter.err[i]
+	}
+	return mounter.FakeMounter.Mount(source, target, fstype, options)
+}
+
+type ExecArgs struct {
+	command string
+	args    []string
+	output  string
+	err     error
+}
+
+func TestSafeFormatAndMount(t *testing.T) {
+	if runtime.GOOS == "darwin" || runtime.GOOS == "windows" {
+		t.Skipf("not supported on GOOS=%s", runtime.GOOS)
+	}
+	mntDir, err := ioutil.TempDir(os.TempDir(), "mount")
+	if err != nil {
+		t.Fatalf("failed to create tmp dir: %v", err)
+	}
+	defer os.RemoveAll(mntDir)
+	tests := []struct {
+		description   string
+		fstype        string
+		mountOptions  []string
+		execScripts   []ExecArgs
+		mountErrs     []error
+		expectedError error
+	}{
+		{
+			description:  "Test a read only mount",
+			fstype:       "ext4",
+			mountOptions: []string{"ro"},
+		},
+		{
+			description: "Test a normal mount",
+			fstype:      "ext4",
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
+			},
+		},
+		{
+			description: "Test 'fsck' fails with exit status 4",
+			fstype:      "ext4",
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", &testingexec.FakeExitError{Status: 4}},
+			},
+			expectedError: fmt.Errorf("'fsck' found errors on device /dev/foo but could not correct them"),
+		},
+		{
+			description: "Test 'fsck' fails with exit status 1 (errors found and corrected)",
+			fstype:      "ext4",
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", &testingexec.FakeExitError{Status: 1}},
+			},
+		},
+		{
+			description: "Test 'fsck' fails with exit status other than 1 and 4 (likely unformatted device)",
+			fstype:      "ext4",
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", &testingexec.FakeExitError{Status: 8}},
+			},
+		},
+		{
+			description: "Test that 'blkid' is called and fails",
+			fstype:      "ext4",
+			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'")},
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", "/dev/foo"}, "DEVNAME=/dev/foo\nTYPE=ext4\n", nil},
+			},
+			expectedError: fmt.Errorf("unknown filesystem type '(null)'"),
+		},
+		{
+			description: "Test that 'blkid' is called and confirms unformatted disk, format fails",
+			fstype:      "ext4",
+			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'")},
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", "/dev/foo"}, "", &testingexec.FakeExitError{Status: 2}},
+				{"mkfs.ext4", []string{"-F", "-m0", "/dev/foo"}, "", fmt.Errorf("formatting failed")},
+			},
+			expectedError: fmt.Errorf("formatting failed"),
+		},
+		{
+			description: "Test that 'blkid' is called and confirms unformatted disk, format passes, second mount fails",
+			fstype:      "ext4",
+			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'"), fmt.Errorf("Still cannot mount")},
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", "/dev/foo"}, "", &testingexec.FakeExitError{Status: 2}},
+				{"mkfs.ext4", []string{"-F", "-m0", "/dev/foo"}, "", nil},
+			},
+			expectedError: fmt.Errorf("Still cannot mount"),
+		},
+		{
+			description: "Test that 'blkid' is called and confirms unformatted disk, format passes, second mount passes",
+			fstype:      "ext4",
+			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'"), nil},
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", "/dev/foo"}, "", &testingexec.FakeExitError{Status: 2}},
+				{"mkfs.ext4", []string{"-F", "-m0", "/dev/foo"}, "", nil},
+			},
+			expectedError: nil,
+		},
+		{
+			description: "Test that 'blkid' is called and confirms unformatted disk, format passes, second mount passes with ext3",
+			fstype:      "ext3",
+			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'"), nil},
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", "/dev/foo"}, "", &testingexec.FakeExitError{Status: 2}},
+				{"mkfs.ext3", []string{"-F", "-m0", "/dev/foo"}, "", nil},
+			},
+			expectedError: nil,
+		},
+		{
+			description: "test that none ext4 fs does not get called with ext4 options.",
+			fstype:      "xfs",
+			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'"), nil},
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", "/dev/foo"}, "", &testingexec.FakeExitError{Status: 2}},
+				{"mkfs.xfs", []string{"/dev/foo"}, "", nil},
+			},
+			expectedError: nil,
+		},
+		{
+			description: "Test that 'blkid' is called and reports ext4 partition",
+			fstype:      "ext3",
+			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'")},
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", "/dev/foo"}, "DEVNAME=/dev/foo\nPTTYPE=dos\n", nil},
+			},
+			expectedError: fmt.Errorf("failed to mount the volume as \"ext3\", it already contains unknown data, probably partitions. Mount error: unknown filesystem type '(null)'"),
+		},
+		{
+			description: "Test that 'blkid' is called but has some usage or other errors (an exit code of 4 is returned)",
+			fstype:      "xfs",
+			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'"), nil},
+			execScripts: []ExecArgs{
+				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-s", "PTTYPE", "-o", "export", "/dev/foo"}, "", &testingexec.FakeExitError{Status: 4}},
+				{"mkfs.xfs", []string{"/dev/foo"}, "", nil},
+			},
+			expectedError: fmt.Errorf("exit 4"),
+		},
+	}
+
+	for _, test := range tests {
+		fakeMounter := ErrorMounter{NewFakeMounter(nil), 0, test.mountErrs}
+		fakeExec := &testingexec.FakeExec{ExactOrder: true}
+		for _, script := range test.execScripts {
+			fakeCmd := &testingexec.FakeCmd{}
+			cmdAction := makeFakeCmd(fakeCmd, script.command, script.args...)
+			outputAction := makeFakeOutput(script.output, script.err)
+			fakeCmd.CombinedOutputScript = append(fakeCmd.CombinedOutputScript, outputAction)
+			fakeExec.CommandScript = append(fakeExec.CommandScript, cmdAction)
+		}
+		mounter := SafeFormatAndMount{
+			Interface: &fakeMounter,
+			Exec:      fakeExec,
+		}
+
+		device := "/dev/foo"
+		dest := mntDir
+		err := mounter.FormatAndMount(device, dest, test.fstype, test.mountOptions)
+		if test.expectedError == nil {
+			if err != nil {
+				t.Errorf("test \"%s\" unexpected non-error: %v", test.description, err)
+			}
+
+			// Check that something was mounted on the directory
+			isNotMountPoint, err := fakeMounter.IsLikelyNotMountPoint(dest)
+			if err != nil || isNotMountPoint {
+				t.Errorf("test \"%s\" the directory was not mounted", test.description)
+			}
+
+			//check that the correct device was mounted
+			mountedDevice, _, err := GetDeviceNameFromMount(fakeMounter.FakeMounter, dest)
+			if err != nil || mountedDevice != device {
+				t.Errorf("test \"%s\" the correct device was not mounted", test.description)
+			}
+		} else {
+			if err == nil || !strings.HasPrefix(err.Error(), test.expectedError.Error()) {
+				t.Errorf("test \"%s\" unexpected error: \n          [%v]. \nExpecting [%v]", test.description, err, test.expectedError)
+			}
+		}
+	}
+}
+
+func makeFakeCmd(fakeCmd *testingexec.FakeCmd, cmd string, args ...string) testingexec.FakeCommandAction {
+	c := cmd
+	a := args
+	return func(cmd string, args ...string) exec.Cmd {
+		command := testingexec.InitFakeCmd(fakeCmd, c, a...)
+		return command
+	}
+}
+
+func makeFakeOutput(output string, err error) testingexec.FakeCombinedOutputAction {
+	o := output
+	return func() ([]byte, error) {
+		return []byte(o), err
+	}
+}