@@ -32,12 +32,19 @@ import (

 	"github.com/docker/docker/pkg/longpath"

 	"github.com/docker/docker/pkg/reexec"

 	"github.com/docker/docker/pkg/system"

+	"github.com/docker/go-units"

 	"github.com/vbatts/tar-split/tar/storage"

 )

 // filterDriver is an HCSShim driver type for the Windows Filter driver.

 const filterDriver = 1

+var (

+	vmcomputedll            = syscall.NewLazyDLL("vmcompute.dll")

+	hcsExpandSandboxSize    = vmcomputedll.NewProc("ExpandSandboxSize")

+	hcsSandboxSizeSupported = hcsExpandSandboxSize.Find() == nil

+)

+

 // init registers the windows graph drivers to the register.

 func init() {

 	graphdriver.Register("windowsfilter", InitFilter)

@@ -118,10 +125,6 @@ func (d *Driver) Create(id, parent, mountLabel string, storageOpt map[string]str

 }

 func (d *Driver) create(id, parent, mountLabel string, readOnly bool, storageOpt map[string]string) error {

-	if len(storageOpt) != 0 {

-		return fmt.Errorf("--storage-opt is not supported for windows")

-	}

-

 	rPId, err := d.resolveID(parent)

 	if err != nil {

 		return err

@@ -184,6 +187,17 @@ func (d *Driver) create(id, parent, mountLabel string, readOnly bool, storageOpt

 		if err := hcsshim.CreateSandboxLayer(d.info, id, parentPath, layerChain); err != nil {

 			return err

 		}

+

+		storageOptions, err := parseStorageOpt(storageOpt)

+		if err != nil {

+			return fmt.Errorf("Failed to parse storage options - %s", err)

+		}

+

+		if hcsSandboxSizeSupported {

+			if err := hcsshim.ExpandSandboxSize(d.info, id, storageOptions.size); err != nil {

+				return err

+			}

+		}

 	}

 	if _, err := os.Lstat(d.dir(parent)); err != nil {

@@ -851,3 +865,27 @@ func (d *Driver) DiffGetter(id string) (graphdriver.FileGetCloser, error) {

 	return &fileGetCloserWithBackupPrivileges{d.dir(id)}, nil

 }

+

+type storageOptions struct {

+	size uint64

+}

+

+func parseStorageOpt(storageOpt map[string]string) (*storageOptions, error) {

+	options := storageOptions{}

+

+	// Read size to change the block device size per container.

+	for key, val := range storageOpt {

+		key := strings.ToLower(key)

+		switch key {

+		case "size":

+			size, err := units.RAMInBytes(val)

+			if err != nil {

+				return nil, err

+			}

+			options.size = uint64(size)

+		default:

+			return nil, fmt.Errorf("Unknown storage option: %s", key)

+		}

+	}

+	return &options, nil

+}

@@ -185,7 +185,6 @@ func (daemon *Daemon) createSpec(c *container.Container) (*libcontainerd.Spec, e

 		Storage: &windowsoci.Storage{

 			Bps:  &c.HostConfig.IOMaximumBandwidth,

 			Iops: &c.HostConfig.IOMaximumIOps,

-			//TODO SandboxSize: ...,

 		},

 	}

 	return (*libcontainerd.Spec)(&s), nil

@@ -155,7 +155,7 @@ Set storage driver options per container.

 This (size) will allow to set the container rootfs size to 120G at creation time. 

 User cannot pass a size less than the Default BaseFS Size. This option is only 

-available for the `devicemapper`, `btrfs`, and `zfs` graph drivers.

+available for the `devicemapper`, `btrfs`, `windowsfilter`, and `zfs` graph drivers.

 ### Specify isolation technology for container (--isolation)

@@ -187,7 +187,7 @@ The `-w` lets the command being executed inside directory given, here

 This (size) will allow to set the container rootfs size to 120G at creation time. 

 User cannot pass a size less than the Default BaseFS Size. This option is only 

-available for the `devicemapper`, `btrfs`, and `zfs` graph drivers.

+available for the `devicemapper`, `btrfs`, `windowsfilter`, and `zfs` graph drivers.

 ### Mount tmpfs (--tmpfs)

@@ -74,9 +74,6 @@ func (clnt *client) Create(containerID string, spec Spec, options ...CreateOptio

 			if spec.Windows.Resources.Storage.Iops != nil {

 				configuration.StorageIOPSMaximum = *spec.Windows.Resources.Storage.Iops

 			}

-			if spec.Windows.Resources.Storage.SandboxSize != nil {

-				configuration.StorageSandboxSize = *spec.Windows.Resources.Storage.SandboxSize

-			}

 		}

 	}