@@ -43,11 +43,12 @@ var (

 	// We retry device removal so many a times that even error messages

 	// will fill up console during normal operation. So only log Fatal

 	// messages by default.

-	logLevel                     = devicemapper.LogLevelFatal

-	driverDeferredRemovalSupport = false

-	enableDeferredRemoval        = false

-	enableDeferredDeletion       = false

-	userBaseSize                 = false

+	logLevel                            = devicemapper.LogLevelFatal

+	driverDeferredRemovalSupport        = false

+	enableDeferredRemoval               = false

+	enableDeferredDeletion              = false

+	userBaseSize                        = false

+	defaultMinFreeSpacePercent   uint32 = 10

 )

 const deviceSetMetaFile string = "deviceset-metadata"

@@ -122,6 +123,7 @@ type DeviceSet struct {

 	deletionWorkerTicker  *time.Ticker

 	uidMaps               []idtools.IDMap

 	gidMaps               []idtools.IDMap

+	minFreeSpacePercent   uint32 //min free space percentage in thinpool

 }

 // DiskUsage contains information about disk usage and is used when reporting Status of a device.

@@ -753,6 +755,38 @@ func (devices *DeviceSet) getNextFreeDeviceID() (int, error) {

 	return 0, fmt.Errorf("devmapper: Unable to find a free device ID")

 }

+func (devices *DeviceSet) poolHasFreeSpace() error {

+	if devices.minFreeSpacePercent == 0 {

+		return nil

+	}

+

+	_, _, dataUsed, dataTotal, metadataUsed, metadataTotal, err := devices.poolStatus()

+	if err != nil {

+		return err

+	}

+

+	minFreeData := (dataTotal * uint64(devices.minFreeSpacePercent)) / 100

+	if minFreeData < 1 {

+		minFreeData = 1

+	}

+	dataFree := dataTotal - dataUsed

+	if dataFree < minFreeData {

+		return fmt.Errorf("devmapper: Thin Pool has %v free data blocks which is less than minimum required %v free data blocks. Create more free space in thin pool or use dm.min_free_space option to change behavior", (dataTotal - dataUsed), minFreeData)

+	}

+

+	minFreeMetadata := (metadataTotal * uint64(devices.minFreeSpacePercent)) / 100

+	if minFreeMetadata < 1 {

+		minFreeData = 1

+	}

+

+	metadataFree := metadataTotal - metadataUsed

+	if metadataFree < minFreeMetadata {

+		return fmt.Errorf("devmapper: Thin Pool has %v free metadata blocks which is less than minimum required %v free metadata blocks. Create more free metadata space in thin pool or use dm.min_free_space option to change behavior", (metadataTotal - metadataUsed), minFreeMetadata)

+	}

+

+	return nil

+}

+

 func (devices *DeviceSet) createRegisterDevice(hash string) (*devInfo, error) {

 	devices.Lock()

 	defer devices.Unlock()

@@ -809,6 +843,10 @@ func (devices *DeviceSet) createRegisterDevice(hash string) (*devInfo, error) {

 }

 func (devices *DeviceSet) createRegisterSnapDevice(hash string, baseInfo *devInfo) error {

+	if err := devices.poolHasFreeSpace(); err != nil {

+		return err

+	}

+

 	deviceID, err := devices.getNextFreeDeviceID()

 	if err != nil {

 		return err

@@ -2437,6 +2475,7 @@ func NewDeviceSet(root string, doInit bool, options []string, uidMaps, gidMaps [

 		deletionWorkerTicker:  time.NewTicker(time.Second * 30),

 		uidMaps:               uidMaps,

 		gidMaps:               gidMaps,

+		minFreeSpacePercent:   defaultMinFreeSpacePercent,

 	}

 	foundBlkDiscard := false

@@ -2512,6 +2551,22 @@ func NewDeviceSet(root string, doInit bool, options []string, uidMaps, gidMaps [

 				return nil, err

 			}

+		case "dm.min_free_space":

+			if !strings.HasSuffix(val, "%") {

+				return nil, fmt.Errorf("devmapper: Option dm.min_free_space requires %% suffix")

+			}

+

+			valstring := strings.TrimSuffix(val, "%")

+			minFreeSpacePercent, err := strconv.ParseUint(valstring, 10, 32)

+			if err != nil {

+				return nil, err

+			}

+

+			if minFreeSpacePercent >= 100 {

+				return nil, fmt.Errorf("devmapper: Invalid value %v for option dm.min_free_space", val)

+			}

+

+			devices.minFreeSpacePercent = uint32(minFreeSpacePercent)

 		default:

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

 		}

@@ -438,6 +438,32 @@ options for `zfs` start with `zfs`.

     when unintentional leaking of mount point happens across multiple mount

     namespaces.

+*  `dm.min_free_space`

+

+    Specifies the min free space percent in thin pool require for new device

+    creation to succeed. This check applies to both free data space as well

+    as free metadata space. Valid values are from 0% - 99%. Value 0% disables

+    free space checking logic. If user does not specify a value for this optoin,

+    then default value for this option is 10%.

+

+    Whenever a new thin pool device is created (during docker pull or

+    during container creation), docker will check minimum free space is

+    available as specified by this parameter. If that is not the case, then

+    device creation will fail and docker operation will fail.

+

+    One will have to create more free space in thin pool to recover from the

+    error. Either delete some of the images and containers from thin pool and

+    create free space or add more storage to thin pool.

+

+    For lvm thin pool, one can add more storage to volume group container thin

+    pool and that should automatically resolve it. If loop devices are being

+    used, then stop docker, grow the size of loop files and restart docker and

+    that should resolve the issue.

+

+    Example use:

+

+        $ docker daemon --storage-opt dm.min_free_space_percent=10%

+

 Currently supported options of `zfs`:

 * `zfs.fsname`

@@ -475,6 +475,30 @@ By default docker will pick up the zfs filesystem where docker graph

 Example use: `docker daemon -s zfs --storage-opt zfs.fsname=zroot/docker`

+#### dm.min_free_space

+

+Specifies the min free space percent in thin pool require for new device

+creation to succeed. This check applies to both free data space as well

+as free metadata space. Valid values are from 0% - 99%. Value 0% disables

+free space checking logic. If user does not specify a value for this optoin,

+then default value for this option is 10%.

+

+Whenever a new thin pool device is created (during docker pull or

+during container creation), docker will check minimum free space is

+available as specified by this parameter. If that is not the case, then

+device creation will fail and docker operation will fail.

+

+One will have to create more free space in thin pool to recover from the

+error. Either delete some of the images and containers from thin pool and

+create free space or add more storage to thin pool.

+

+For lvm thin pool, one can add more storage to volume group container thin

+pool and that should automatically resolve it. If loop devices are being

+used, then stop docker, grow the size of loop files and restart docker and

+that should resolve the issue.

+

+Example use: `docker daemon --storage-opt dm.min_free_space_percent=10%`

+

 # CLUSTER STORE OPTIONS

 The daemon uses libkv to advertise