@@ -24,6 +24,7 @@ import (

 	"github.com/docker/docker/pkg/mount"

 	"github.com/docker/docker/pkg/parsers"

 	"github.com/docker/docker/pkg/parsers/kernel"

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

 	"github.com/opencontainers/runc/libcontainer/label"

 )

@@ -76,15 +77,25 @@ const (

 	idLength = 26

 )

+type overlayOptions struct {

+	overrideKernelCheck bool

+	quota               graphdriver.Quota

+}

+

 // Driver contains information about the home directory and the list of active mounts that are created using this driver.

 type Driver struct {

-	home    string

-	uidMaps []idtools.IDMap

-	gidMaps []idtools.IDMap

-	ctr     *graphdriver.RefCounter

+	home     string

+	uidMaps  []idtools.IDMap

+	gidMaps  []idtools.IDMap

+	ctr      *graphdriver.RefCounter

+	quotaCtl *graphdriver.QuotaCtl

+	options  overlayOptions

 }

-var backingFs = "<unknown>"

+var (

+	backingFs             = "<unknown>"

+	projectQuotaSupported = false

+)

 func init() {

 	graphdriver.Register(driverName, Init)

@@ -150,11 +161,16 @@ func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (grap

 		ctr:     graphdriver.NewRefCounter(graphdriver.NewFsChecker(graphdriver.FsMagicOverlay)),

 	}

-	return d, nil

-}

+	if backingFs == "xfs" {

+		// Try to enable project quota support over xfs.

+		if d.quotaCtl, err = graphdriver.NewQuotaCtl(home); err == nil {

+			projectQuotaSupported = true

+		}

+	}

-type overlayOptions struct {

-	overrideKernelCheck bool

+	logrus.Debugf("backingFs=%s,  projectQuotaSupported=%v", backingFs, projectQuotaSupported)

+

+	return d, nil

 }

 func parseOptions(options []string) (*overlayOptions, error) {

@@ -171,6 +187,7 @@ func parseOptions(options []string) (*overlayOptions, error) {

 			if err != nil {

 				return nil, err

 			}

+

 		default:

 			return nil, fmt.Errorf("overlay2: Unknown option %s\n", key)

 		}

@@ -253,8 +270,8 @@ func (d *Driver) CreateReadWrite(id, parent, mountLabel string, storageOpt map[s

 // The parent filesystem is used to configure these directories for the overlay.

 func (d *Driver) Create(id, parent, mountLabel string, storageOpt map[string]string) (retErr error) {

-	if len(storageOpt) != 0 {

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

+	if len(storageOpt) != 0 && !projectQuotaSupported {

+		return fmt.Errorf("--storage-opt is supported only for overlay over xfs with 'pquota' mount option")

 	}

 	dir := d.dir(id)

@@ -277,6 +294,20 @@ func (d *Driver) Create(id, parent, mountLabel string, storageOpt map[string]str

 		}

 	}()

+	if len(storageOpt) > 0 {

+		driver := &Driver{}

+		if err := d.parseStorageOpt(storageOpt, driver); err != nil {

+			return err

+		}

+

+		if driver.options.quota.Size > 0 {

+			// Set container disk quota limit

+			if err := d.quotaCtl.SetQuota(dir, driver.options.quota); err != nil {

+				return err

+			}

+		}

+	}

+

 	if err := idtools.MkdirAs(path.Join(dir, "diff"), 0755, rootUID, rootGID); err != nil {

 		return err

 	}

@@ -316,6 +347,26 @@ func (d *Driver) Create(id, parent, mountLabel string, storageOpt map[string]str

 	return nil

 }

+// Parse overlay storage options

+func (d *Driver) parseStorageOpt(storageOpt map[string]string, driver *Driver) error {

+	// Read size to set the disk project quota per container

+	for key, val := range storageOpt {

+		key := strings.ToLower(key)

+		switch key {

+		case "size":

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

+			if err != nil {

+				return err

+			}

+			driver.options.quota.Size = uint64(size)

+		default:

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

+		}

+	}

+

+	return nil

+}

+

 func (d *Driver) getLower(parent string) (string, error) {

 	parentDir := d.dir(parent)

@@ -171,8 +171,13 @@ Set storage driver options per container.

     $ docker create -it --storage-opt size=120G fedora /bin/bash

 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`, `windowsfilter`, and `zfs` graph drivers.

+This option is only available for the `devicemapper`, `btrfs`, `overlay2`,

+`windowsfilter` and `zfs` graph drivers.

+For the `devicemapper`, `btrfs`, `windowsfilter` and `zfs` graph drivers,

+user cannot pass a size less than the Default BaseFS Size.

+For the `overlay2` storage driver, the size option is only available if the

+backing fs is `xfs` and mounted with the `pquota` mount option.

+Under these conditions, user can pass any size less then the backing fs size.

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

@@ -198,8 +198,13 @@ The `-w` lets the command being executed inside directory given, here

     $ docker run -it --storage-opt size=120G fedora /bin/bash

 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`, `windowsfilter`, and `zfs` graph drivers.

+This option is only available for the `devicemapper`, `btrfs`, `overlay2`,

+`windowsfilter` and `zfs` graph drivers.

+For the `devicemapper`, `btrfs`, `windowsfilter` and `zfs` graph drivers,

+user cannot pass a size less than the Default BaseFS Size.

+For the `overlay2` storage driver, the size option is only available if the

+backing fs is `xfs` and mounted with the `pquota` mount option.

+Under these conditions, user can pass any size less then the backing fs size.

 ### Mount tmpfs (--tmpfs)

@@ -343,8 +343,11 @@ unit, `b` is used. Set LIMIT to `-1` to enable unlimited swap.

    $ docker create -it --storage-opt size=120G fedora /bin/bash

-   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.

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

+   This option is only available for the `devicemapper`, `btrfs`, `overlay2` and `zfs` graph drivers.

+   For the `devicemapper`, `btrfs` and `zfs` storage drivers, user cannot pass a size less than the Default BaseFS Size.

+   For the `overlay2` storage driver, the size option is only available if the backing fs is `xfs` and mounted with the `pquota` mount option.

+   Under these conditions, user can pass any size less then the backing fs size.

 **--stop-signal**=*SIGTERM*

   Signal to stop a container. Default is SIGTERM.

@@ -493,8 +493,11 @@ incompatible with any restart policy other than `none`.

    $ docker run -it --storage-opt size=120G fedora /bin/bash

-   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.

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

+   This option is only available for the `devicemapper`, `btrfs`, `overlay2`  and `zfs` graph drivers.

+   For the `devicemapper`, `btrfs` and `zfs` storage drivers, user cannot pass a size less than the Default BaseFS Size.

+   For the `overlay2` storage driver, the size option is only available if the backing fs is `xfs` and mounted with the `pquota` mount option.

+   Under these conditions, user can pass any size less then the backing fs size.

 **--stop-signal**=*SIGTERM*

   Signal to stop a container. Default is SIGTERM.