// +build linux
package devmapper
import (
"bufio"
"encoding/json"
"fmt"
"io"
"io/ioutil"
"os"
"os/exec"
"path"
"path/filepath"
"reflect"
"strconv"
"strings"
"sync"
"time"
"github.com/docker/docker/daemon/graphdriver"
"github.com/docker/docker/dockerversion"
"github.com/docker/docker/pkg/devicemapper"
"github.com/docker/docker/pkg/idtools"
"github.com/docker/docker/pkg/loopback"
"github.com/docker/docker/pkg/mount"
"github.com/docker/docker/pkg/parsers"
units "github.com/docker/go-units"
"github.com/opencontainers/selinux/go-selinux/label"
"github.com/pkg/errors"
"github.com/sirupsen/logrus"
"golang.org/x/sys/unix"
)
var (
defaultDataLoopbackSize int64 = 100 * 1024 * 1024 * 1024
defaultMetaDataLoopbackSize int64 = 2 * 1024 * 1024 * 1024
defaultBaseFsSize uint64 = 10 * 1024 * 1024 * 1024
defaultThinpBlockSize uint32 = 128 // 64K = 128 512b sectors
defaultUdevSyncOverride = false
maxDeviceID = 0xffffff // 24 bit, pool limit
deviceIDMapSz = (maxDeviceID + 1) / 8
driverDeferredRemovalSupport = false
enableDeferredRemoval = false
enableDeferredDeletion = false
userBaseSize = false
defaultMinFreeSpacePercent uint32 = 10
lvmSetupConfigForce bool
)
const deviceSetMetaFile string = "deviceset-metadata"
const transactionMetaFile string = "transaction-metadata"
type transaction struct {
OpenTransactionID uint64 `json:"open_transaction_id"`
DeviceIDHash string `json:"device_hash"`
DeviceID int `json:"device_id"`
}
type devInfo struct {
Hash string `json:"-"`
DeviceID int `json:"device_id"`
Size uint64 `json:"size"`
TransactionID uint64 `json:"transaction_id"`
Initialized bool `json:"initialized"`
Deleted bool `json:"deleted"`
devices *DeviceSet
// The global DeviceSet lock guarantees that we serialize all
// the calls to libdevmapper (which is not threadsafe), but we
// sometimes release that lock while sleeping. In that case
// this per-device lock is still held, protecting against
// other accesses to the device that we're doing the wait on.
//
// WARNING: In order to avoid AB-BA deadlocks when releasing
// the global lock while holding the per-device locks all
// device locks must be acquired *before* the device lock, and
// multiple device locks should be acquired parent before child.
lock sync.Mutex
}
type metaData struct {
Devices map[string]*devInfo `json:"Devices"`
}
// DeviceSet holds information about list of devices
type DeviceSet struct {
metaData `json:"-"`
sync.Mutex `json:"-"` // Protects all fields of DeviceSet and serializes calls into libdevmapper
root string
devicePrefix string
TransactionID uint64 `json:"-"`
NextDeviceID int `json:"next_device_id"`
deviceIDMap []byte
// Options
dataLoopbackSize int64
metaDataLoopbackSize int64
baseFsSize uint64
filesystem string
mountOptions string
mkfsArgs []string
dataDevice string // block or loop dev
dataLoopFile string // loopback file, if used
metadataDevice string // block or loop dev
metadataLoopFile string // loopback file, if used
doBlkDiscard bool
thinpBlockSize uint32
thinPoolDevice string
transaction `json:"-"`
overrideUdevSyncCheck bool
deferredRemove bool // use deferred removal
deferredDelete bool // use deferred deletion
BaseDeviceUUID string // save UUID of base device
BaseDeviceFilesystem string // save filesystem of base device
nrDeletedDevices uint // number of deleted devices
deletionWorkerTicker *time.Ticker
uidMaps []idtools.IDMap
gidMaps []idtools.IDMap
minFreeSpacePercent uint32 //min free space percentage in thinpool
xfsNospaceRetries string // max retries when xfs receives ENOSPC
lvmSetupConfig directLVMConfig
}
// DiskUsage contains information about disk usage and is used when reporting Status of a device.
type DiskUsage struct {
// Used bytes on the disk.
Used uint64
// Total bytes on the disk.
Total uint64
// Available bytes on the disk.
Available uint64
}
// Status returns the information about the device.
type Status struct {
// PoolName is the name of the data pool.
PoolName string
// DataFile is the actual block device for data.
DataFile string
// DataLoopback loopback file, if used.
DataLoopback string
// MetadataFile is the actual block device for metadata.
MetadataFile string
// MetadataLoopback is the loopback file, if used.
MetadataLoopback string
// Data is the disk used for data.
Data DiskUsage
// Metadata is the disk used for meta data.
Metadata DiskUsage
// BaseDeviceSize is base size of container and image
BaseDeviceSize uint64
// BaseDeviceFS is backing filesystem.
BaseDeviceFS string
// SectorSize size of the vector.
SectorSize uint64
// UdevSyncSupported is true if sync is supported.
UdevSyncSupported bool
// DeferredRemoveEnabled is true then the device is not unmounted.
DeferredRemoveEnabled bool
// True if deferred deletion is enabled. This is different from
// deferred removal. "removal" means that device mapper device is
// deactivated. Thin device is still in thin pool and can be activated
// again. But "deletion" means that thin device will be deleted from
// thin pool and it can't be activated again.
DeferredDeleteEnabled bool
DeferredDeletedDeviceCount uint
MinFreeSpace uint64
}
// Structure used to export image/container metadata in docker inspect.
type deviceMetadata struct {
deviceID int
deviceSize uint64 // size in bytes
deviceName string // Device name as used during activation
}
// DevStatus returns information about device mounted containing its id, size and sector information.
type DevStatus struct {
// DeviceID is the id of the device.
DeviceID int
// Size is the size of the filesystem.
Size uint64
// TransactionID is a unique integer per device set used to identify an operation on the file system, this number is incremental.
TransactionID uint64
// SizeInSectors indicates the size of the sectors allocated.
SizeInSectors uint64
// MappedSectors indicates number of mapped sectors.
MappedSectors uint64
// HighestMappedSector is the pointer to the highest mapped sector.
HighestMappedSector uint64
}
func getDevName(name string) string {
return "/dev/mapper/" + name
}
func (info *devInfo) Name() string {
hash := info.Hash
if hash == "" {
hash = "base"
}
return fmt.Sprintf("%s-%s", info.devices.devicePrefix, hash)
}
func (info *devInfo) DevName() string {
return getDevName(info.Name())
}
func (devices *DeviceSet) loopbackDir() string {
return path.Join(devices.root, "devicemapper")
}
func (devices *DeviceSet) metadataDir() string {
return path.Join(devices.root, "metadata")
}
func (devices *DeviceSet) metadataFile(info *devInfo) string {
file := info.Hash
if file == "" {
file = "base"
}
return path.Join(devices.metadataDir(), file)
}
func (devices *DeviceSet) transactionMetaFile() string {
return path.Join(devices.metadataDir(), transactionMetaFile)
}
func (devices *DeviceSet) deviceSetMetaFile() string {
return path.Join(devices.metadataDir(), deviceSetMetaFile)
}
func (devices *DeviceSet) oldMetadataFile() string {
return path.Join(devices.loopbackDir(), "json")
}
func (devices *DeviceSet) getPoolName() string {
if devices.thinPoolDevice == "" {
return devices.devicePrefix + "-pool"
}
return devices.thinPoolDevice
}
func (devices *DeviceSet) getPoolDevName() string {
return getDevName(devices.getPoolName())
}
func (devices *DeviceSet) hasImage(name string) bool {
dirname := devices.loopbackDir()
filename := path.Join(dirname, name)
_, err := os.Stat(filename)
return err == nil
}
// ensureImage creates a sparse file of <size> bytes at the path
// <root>/devicemapper/<name>.
// If the file already exists and new size is larger than its current size, it grows to the new size.
// Either way it returns the full path.
func (devices *DeviceSet) ensureImage(name string, size int64) (string, error) {
dirname := devices.loopbackDir()
filename := path.Join(dirname, name)
uid, gid, err := idtools.GetRootUIDGID(devices.uidMaps, devices.gidMaps)
if err != nil {
return "", err
}
if err := idtools.MkdirAllAs(dirname, 0700, uid, gid); err != nil && !os.IsExist(err) {
return "", err
}
if fi, err := os.Stat(filename); err != nil {
if !os.IsNotExist(err) {
return "", err
}
logrus.Debugf("devmapper: Creating loopback file %s for device-manage use", filename)
file, err := os.OpenFile(filename, os.O_RDWR|os.O_CREATE, 0600)
if err != nil {
return "", err
}
defer file.Close()
if err := file.Truncate(size); err != nil {
return "", err
}
} else {
if fi.Size() < size {
file, err := os.OpenFile(filename, os.O_RDWR|os.O_CREATE, 0600)
if err != nil {
return "", err
}
defer file.Close()
if err := file.Truncate(size); err != nil {
return "", fmt.Errorf("devmapper: Unable to grow loopback file %s: %v", filename, err)
}
} else if fi.Size() > size {
logrus.Warnf("devmapper: Can't shrink loopback file %s", filename)
}
}
return filename, nil
}
func (devices *DeviceSet) allocateTransactionID() uint64 {
devices.OpenTransactionID = devices.TransactionID + 1
return devices.OpenTransactionID
}
func (devices *DeviceSet) updatePoolTransactionID() error {
if err := devicemapper.SetTransactionID(devices.getPoolDevName(), devices.TransactionID, devices.OpenTransactionID); err != nil {
return fmt.Errorf("devmapper: Error setting devmapper transaction ID: %s", err)
}
devices.TransactionID = devices.OpenTransactionID
return nil
}
func (devices *DeviceSet) removeMetadata(info *devInfo) error {
if err := os.RemoveAll(devices.metadataFile(info)); err != nil {
return fmt.Errorf("devmapper: Error removing metadata file %s: %s", devices.metadataFile(info), err)
}
return nil
}
// Given json data and file path, write it to disk
func (devices *DeviceSet) writeMetaFile(jsonData []byte, filePath string) error {
tmpFile, err := ioutil.TempFile(devices.metadataDir(), ".tmp")
if err != nil {
return fmt.Errorf("devmapper: Error creating metadata file: %s", err)
}
n, err := tmpFile.Write(jsonData)
if err != nil {
return fmt.Errorf("devmapper: Error writing metadata to %s: %s", tmpFile.Name(), err)
}
if n < len(jsonData) {
return io.ErrShortWrite
}
if err := tmpFile.Sync(); err != nil {
return fmt.Errorf("devmapper: Error syncing metadata file %s: %s", tmpFile.Name(), err)
}
if err := tmpFile.Close(); err != nil {
return fmt.Errorf("devmapper: Error closing metadata file %s: %s", tmpFile.Name(), err)
}
if err := os.Rename(tmpFile.Name(), filePath); err != nil {
return fmt.Errorf("devmapper: Error committing metadata file %s: %s", tmpFile.Name(), err)
}
return nil
}
func (devices *DeviceSet) saveMetadata(info *devInfo) error {
jsonData, err := json.Marshal(info)
if err != nil {
return fmt.Errorf("devmapper: Error encoding metadata to json: %s", err)
}
if err := devices.writeMetaFile(jsonData, devices.metadataFile(info)); err != nil {
return err
}
return nil
}
func (devices *DeviceSet) markDeviceIDUsed(deviceID int) {
var mask byte
i := deviceID % 8
mask = 1 << uint(i)
devices.deviceIDMap[deviceID/8] = devices.deviceIDMap[deviceID/8] | mask
}
func (devices *DeviceSet) markDeviceIDFree(deviceID int) {
var mask byte
i := deviceID % 8
mask = ^(1 << uint(i))
devices.deviceIDMap[deviceID/8] = devices.deviceIDMap[deviceID/8] & mask
}
func (devices *DeviceSet) isDeviceIDFree(deviceID int) bool {
var mask byte
i := deviceID % 8
mask = (1 << uint(i))
return (devices.deviceIDMap[deviceID/8] & mask) == 0
}
// Should be called with devices.Lock() held.
func (devices *DeviceSet) lookupDevice(hash string) (*devInfo, error) {
info := devices.Devices[hash]
if info == nil {
info = devices.loadMetadata(hash)
if info == nil {
return nil, fmt.Errorf("devmapper: Unknown device %s", hash)
}
devices.Devices[hash] = info
}
return info, nil
}
func (devices *DeviceSet) lookupDeviceWithLock(hash string) (*devInfo, error) {
devices.Lock()
defer devices.Unlock()
info, err := devices.lookupDevice(hash)
return info, err
}
// This function relies on that device hash map has been loaded in advance.
// Should be called with devices.Lock() held.
func (devices *DeviceSet) constructDeviceIDMap() {
logrus.Debug("devmapper: constructDeviceIDMap()")
defer logrus.Debug("devmapper: constructDeviceIDMap() END")
for _, info := range devices.Devices {
devices.markDeviceIDUsed(info.DeviceID)
logrus.Debugf("devmapper: Added deviceId=%d to DeviceIdMap", info.DeviceID)
}
}
func (devices *DeviceSet) deviceFileWalkFunction(path string, finfo os.FileInfo) error {
// Skip some of the meta files which are not device files.
if strings.HasSuffix(finfo.Name(), ".migrated") {
logrus.Debugf("devmapper: Skipping file %s", path)
return nil
}
if strings.HasPrefix(finfo.Name(), ".") {
logrus.Debugf("devmapper: Skipping file %s", path)
return nil
}
if finfo.Name() == deviceSetMetaFile {
logrus.Debugf("devmapper: Skipping file %s", path)
return nil
}
if finfo.Name() == transactionMetaFile {
logrus.Debugf("devmapper: Skipping file %s", path)
return nil
}
logrus.Debugf("devmapper: Loading data for file %s", path)
hash := finfo.Name()
if hash == "base" {
hash = ""
}
// Include deleted devices also as cleanup delete device logic
// will go through it and see if there are any deleted devices.
if _, err := devices.lookupDevice(hash); err != nil {
return fmt.Errorf("devmapper: Error looking up device %s:%v", hash, err)
}
return nil
}
func (devices *DeviceSet) loadDeviceFilesOnStart() error {
logrus.Debug("devmapper: loadDeviceFilesOnStart()")
defer logrus.Debug("devmapper: loadDeviceFilesOnStart() END")
var scan = func(path string, info os.FileInfo, err error) error {
if err != nil {
logrus.Debugf("devmapper: Can't walk the file %s", path)
return nil
}
// Skip any directories
if info.IsDir() {
return nil
}
return devices.deviceFileWalkFunction(path, info)
}
return filepath.Walk(devices.metadataDir(), scan)
}
// Should be called with devices.Lock() held.
func (devices *DeviceSet) unregisterDevice(hash string) error {
logrus.Debugf("devmapper: unregisterDevice(%v)", hash)
info := &devInfo{
Hash: hash,
}
delete(devices.Devices, hash)
if err := devices.removeMetadata(info); err != nil {
logrus.Debugf("devmapper: Error removing metadata: %s", err)
return err
}
return nil
}
// Should be called with devices.Lock() held.
func (devices *DeviceSet) registerDevice(id int, hash string, size uint64, transactionID uint64) (*devInfo, error) {
logrus.Debugf("devmapper: registerDevice(%v, %v)", id, hash)
info := &devInfo{
Hash: hash,
DeviceID: id,
Size: size,
TransactionID: transactionID,
Initialized: false,
devices: devices,
}
devices.Devices[hash] = info
if err := devices.saveMetadata(info); err != nil {
// Try to remove unused device
delete(devices.Devices, hash)
return nil, err
}
return info, nil
}
func (devices *DeviceSet) activateDeviceIfNeeded(info *devInfo, ignoreDeleted bool) error {
logrus.Debugf("devmapper: activateDeviceIfNeeded(%v)", info.Hash)
if info.Deleted && !ignoreDeleted {
return fmt.Errorf("devmapper: Can't activate device %v as it is marked for deletion", info.Hash)
}
// Make sure deferred removal on device is canceled, if one was
// scheduled.
if err := devices.cancelDeferredRemovalIfNeeded(info); err != nil {
return fmt.Errorf("devmapper: Device Deferred Removal Cancellation Failed: %s", err)
}
if devinfo, _ := devicemapper.GetInfo(info.Name()); devinfo != nil && devinfo.Exists != 0 {
return nil
}
return devicemapper.ActivateDevice(devices.getPoolDevName(), info.Name(), info.DeviceID, info.Size)
}
// Return true only if kernel supports xfs and mkfs.xfs is available
func xfsSupported() bool {
// Make sure mkfs.xfs is available
if _, err := exec.LookPath("mkfs.xfs"); err != nil {
return false
}
// Check if kernel supports xfs filesystem or not.
exec.Command("modprobe", "xfs").Run()
f, err := os.Open("/proc/filesystems")
if err != nil {
logrus.Warnf("devmapper: Could not check if xfs is supported: %v", err)
return false
}
defer f.Close()
s := bufio.NewScanner(f)
for s.Scan() {
if strings.HasSuffix(s.Text(), "\txfs") {
return true
}
}
if err := s.Err(); err != nil {
logrus.Warnf("devmapper: Could not check if xfs is supported: %v", err)
}
return false
}
func determineDefaultFS() string {
if xfsSupported() {
return "xfs"
}
logrus.Warn("devmapper: XFS is not supported in your system. Either the kernel doesn't support it or mkfs.xfs is not in your PATH. Defaulting to ext4 filesystem")
return "ext4"
}
func (devices *DeviceSet) createFilesystem(info *devInfo) (err error) {
devname := info.DevName()
args := []string{}
args = append(args, devices.mkfsArgs...)
args = append(args, devname)
if devices.filesystem == "" {
devices.filesystem = determineDefaultFS()
}
if err := devices.saveBaseDeviceFilesystem(devices.filesystem); err != nil {
return err
}
logrus.Infof("devmapper: Creating filesystem %s on device %s", devices.filesystem, info.Name())
defer func() {
if err != nil {
logrus.Infof("devmapper: Error while creating filesystem %s on device %s: %v", devices.filesystem, info.Name(), err)
} else {
logrus.Infof("devmapper: Successfully created filesystem %s on device %s", devices.filesystem, info.Name())
}
}()
switch devices.filesystem {
case "xfs":
err = exec.Command("mkfs.xfs", args...).Run()
case "ext4":
err = exec.Command("mkfs.ext4", append([]string{"-E", "nodiscard,lazy_itable_init=0,lazy_journal_init=0"}, args...)...).Run()
if err != nil {
err = exec.Command("mkfs.ext4", append([]string{"-E", "nodiscard,lazy_itable_init=0"}, args...)...).Run()
}
if err != nil {
return err
}
err = exec.Command("tune2fs", append([]string{"-c", "-1", "-i", "0"}, devname)...).Run()
default:
err = fmt.Errorf("devmapper: Unsupported filesystem type %s", devices.filesystem)
}
return
}
func (devices *DeviceSet) migrateOldMetaData() error {
// Migrate old metadata file
jsonData, err := ioutil.ReadFile(devices.oldMetadataFile())
if err != nil && !os.IsNotExist(err) {
return err
}
if jsonData != nil {
m := metaData{Devices: make(map[string]*devInfo)}
if err := json.Unmarshal(jsonData, &m); err != nil {
return err
}
for hash, info := range m.Devices {
info.Hash = hash
devices.saveMetadata(info)
}
if err := os.Rename(devices.oldMetadataFile(), devices.oldMetadataFile()+".migrated"); err != nil {
return err
}
}
return nil
}
// Cleanup deleted devices. It assumes that all the devices have been
// loaded in the hash table.
func (devices *DeviceSet) cleanupDeletedDevices() error {
devices.Lock()
// If there are no deleted devices, there is nothing to do.
if devices.nrDeletedDevices == 0 {
devices.Unlock()
return nil
}
var deletedDevices []*devInfo
for _, info := range devices.Devices {
if !info.Deleted {
continue
}
logrus.Debugf("devmapper: Found deleted device %s.", info.Hash)
deletedDevices = append(deletedDevices, info)
}
// Delete the deleted devices. DeleteDevice() first takes the info lock
// and then devices.Lock(). So drop it to avoid deadlock.
devices.Unlock()
for _, info := range deletedDevices {
// This will again try deferred deletion.
if err := devices.DeleteDevice(info.Hash, false); err != nil {
logrus.Warnf("devmapper: Deletion of device %s, device_id=%v failed:%v", info.Hash, info.DeviceID, err)
}
}
return nil
}
func (devices *DeviceSet) countDeletedDevices() {
for _, info := range devices.Devices {
if !info.Deleted {
continue
}
devices.nrDeletedDevices++
}
}
func (devices *DeviceSet) startDeviceDeletionWorker() {
// Deferred deletion is not enabled. Don't do anything.
if !devices.deferredDelete {
return
}
logrus.Debug("devmapper: Worker to cleanup deleted devices started")
for range devices.deletionWorkerTicker.C {
devices.cleanupDeletedDevices()
}
}
func (devices *DeviceSet) initMetaData() error {
devices.Lock()
defer devices.Unlock()
if err := devices.migrateOldMetaData(); err != nil {
return err
}
_, transactionID, _, _, _, _, err := devices.poolStatus()
if err != nil {
return err
}
devices.TransactionID = transactionID
if err := devices.loadDeviceFilesOnStart(); err != nil {
return fmt.Errorf("devmapper: Failed to load device files:%v", err)
}
devices.constructDeviceIDMap()
devices.countDeletedDevices()
if err := devices.processPendingTransaction(); err != nil {
return err
}
// Start a goroutine to cleanup Deleted Devices
go devices.startDeviceDeletionWorker()
return nil
}
func (devices *DeviceSet) incNextDeviceID() {
// IDs are 24bit, so wrap around
devices.NextDeviceID = (devices.NextDeviceID + 1) & maxDeviceID
}
func (devices *DeviceSet) getNextFreeDeviceID() (int, error) {
devices.incNextDeviceID()
for i := 0; i <= maxDeviceID; i++ {
if devices.isDeviceIDFree(devices.NextDeviceID) {
devices.markDeviceIDUsed(devices.NextDeviceID)
return devices.NextDeviceID, nil
}
devices.incNextDeviceID()
}
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 {
minFreeMetadata = 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()
deviceID, err := devices.getNextFreeDeviceID()
if err != nil {
return nil, err
}
if err := devices.openTransaction(hash, deviceID); err != nil {
logrus.Debugf("devmapper: Error opening transaction hash = %s deviceID = %d", hash, deviceID)
devices.markDeviceIDFree(deviceID)
return nil, err
}
for {
if err := devicemapper.CreateDevice(devices.getPoolDevName(), deviceID); err != nil {
if devicemapper.DeviceIDExists(err) {
// Device ID already exists. This should not
// happen. Now we have a mechanism to find
// a free device ID. So something is not right.
// Give a warning and continue.
logrus.Errorf("devmapper: Device ID %d exists in pool but it is supposed to be unused", deviceID)
deviceID, err = devices.getNextFreeDeviceID()
if err != nil {
return nil, err
}
// Save new device id into transaction
devices.refreshTransaction(deviceID)
continue
}
logrus.Debugf("devmapper: Error creating device: %s", err)
devices.markDeviceIDFree(deviceID)
return nil, err
}
break
}
logrus.Debugf("devmapper: Registering device (id %v) with FS size %v", deviceID, devices.baseFsSize)
info, err := devices.registerDevice(deviceID, hash, devices.baseFsSize, devices.OpenTransactionID)
if err != nil {
_ = devicemapper.DeleteDevice(devices.getPoolDevName(), deviceID)
devices.markDeviceIDFree(deviceID)
return nil, err
}
if err := devices.closeTransaction(); err != nil {
devices.unregisterDevice(hash)
devicemapper.DeleteDevice(devices.getPoolDevName(), deviceID)
devices.markDeviceIDFree(deviceID)
return nil, err
}
return info, nil
}
func (devices *DeviceSet) takeSnapshot(hash string, baseInfo *devInfo, size uint64) error {
var (
devinfo *devicemapper.Info
err error
)
if err = devices.poolHasFreeSpace(); err != nil {
return err
}
if devices.deferredRemove {
devinfo, err = devicemapper.GetInfoWithDeferred(baseInfo.Name())
if err != nil {
return err
}
if devinfo != nil && devinfo.DeferredRemove != 0 {
err = devices.cancelDeferredRemoval(baseInfo)
if err != nil {
// If Error is ErrEnxio. Device is probably already gone. Continue.
if err != devicemapper.ErrEnxio {
return err
}
devinfo = nil
} else {
defer devices.deactivateDevice(baseInfo)
}
}
} else {
devinfo, err = devicemapper.GetInfo(baseInfo.Name())
if err != nil {
return err
}
}
doSuspend := devinfo != nil && devinfo.Exists != 0
if doSuspend {
if err = devicemapper.SuspendDevice(baseInfo.Name()); err != nil {
return err
}
defer devicemapper.ResumeDevice(baseInfo.Name())
}
if err = devices.createRegisterSnapDevice(hash, baseInfo, size); err != nil {
return err
}
return nil
}
func (devices *DeviceSet) createRegisterSnapDevice(hash string, baseInfo *devInfo, size uint64) error {
deviceID, err := devices.getNextFreeDeviceID()
if err != nil {
return err
}
if err := devices.openTransaction(hash, deviceID); err != nil {
logrus.Debugf("devmapper: Error opening transaction hash = %s deviceID = %d", hash, deviceID)
devices.markDeviceIDFree(deviceID)
return err
}
for {
if err := devicemapper.CreateSnapDeviceRaw(devices.getPoolDevName(), deviceID, baseInfo.DeviceID); err != nil {
if devicemapper.DeviceIDExists(err) {
// Device ID already exists. This should not
// happen. Now we have a mechanism to find
// a free device ID. So something is not right.
// Give a warning and continue.
logrus.Errorf("devmapper: Device ID %d exists in pool but it is supposed to be unused", deviceID)
deviceID, err = devices.getNextFreeDeviceID()
if err != nil {
return err
}
// Save new device id into transaction
devices.refreshTransaction(deviceID)
continue
}
logrus.Debugf("devmapper: Error creating snap device: %s", err)
devices.markDeviceIDFree(deviceID)
return err
}
break
}
if _, err := devices.registerDevice(deviceID, hash, size, devices.OpenTransactionID); err != nil {
devicemapper.DeleteDevice(devices.getPoolDevName(), deviceID)
devices.markDeviceIDFree(deviceID)
logrus.Debugf("devmapper: Error registering device: %s", err)
return err
}
if err := devices.closeTransaction(); err != nil {
devices.unregisterDevice(hash)
devicemapper.DeleteDevice(devices.getPoolDevName(), deviceID)
devices.markDeviceIDFree(deviceID)
return err
}
return nil
}
func (devices *DeviceSet) loadMetadata(hash string) *devInfo {
info := &devInfo{Hash: hash, devices: devices}
jsonData, err := ioutil.ReadFile(devices.metadataFile(info))
if err != nil {
logrus.Debugf("devmapper: Failed to read %s with err: %v", devices.metadataFile(info), err)
return nil
}
if err := json.Unmarshal(jsonData, &info); err != nil {
logrus.Debugf("devmapper: Failed to unmarshal devInfo from %s with err: %v", devices.metadataFile(info), err)
return nil
}
if info.DeviceID > maxDeviceID {
logrus.Errorf("devmapper: Ignoring Invalid DeviceId=%d", info.DeviceID)
return nil
}
return info
}
func getDeviceUUID(device string) (string, error) {
out, err := exec.Command("blkid", "-s", "UUID", "-o", "value", device).Output()
if err != nil {
return "", fmt.Errorf("devmapper: Failed to find uuid for device %s:%v", device, err)
}
uuid := strings.TrimSuffix(string(out), "\n")
uuid = strings.TrimSpace(uuid)
logrus.Debugf("devmapper: UUID for device: %s is:%s", device, uuid)
return uuid, nil
}
func (devices *DeviceSet) getBaseDeviceSize() uint64 {
info, _ := devices.lookupDevice("")
if info == nil {
return 0
}
return info.Size
}
func (devices *DeviceSet) getBaseDeviceFS() string {
return devices.BaseDeviceFilesystem
}
func (devices *DeviceSet) verifyBaseDeviceUUIDFS(baseInfo *devInfo) error {
devices.Lock()
defer devices.Unlock()
if err := devices.activateDeviceIfNeeded(baseInfo, false); err != nil {
return err
}
defer devices.deactivateDevice(baseInfo)
uuid, err := getDeviceUUID(baseInfo.DevName())
if err != nil {
return err
}
if devices.BaseDeviceUUID != uuid {
return fmt.Errorf("devmapper: Current Base Device UUID:%s does not match with stored UUID:%s. Possibly using a different thin pool than last invocation", uuid, devices.BaseDeviceUUID)
}
if devices.BaseDeviceFilesystem == "" {
fsType, err := ProbeFsType(baseInfo.DevName())
if err != nil {
return err
}
if err := devices.saveBaseDeviceFilesystem(fsType); err != nil {
return err
}
}
// If user specified a filesystem using dm.fs option and current
// file system of base image is not same, warn user that dm.fs
// will be ignored.
if devices.BaseDeviceFilesystem != devices.filesystem {
logrus.Warnf("devmapper: Base device already exists and has filesystem %s on it. User specified filesystem %s will be ignored.", devices.BaseDeviceFilesystem, devices.filesystem)
devices.filesystem = devices.BaseDeviceFilesystem
}
return nil
}
func (devices *DeviceSet) saveBaseDeviceFilesystem(fs string) error {
devices.BaseDeviceFilesystem = fs
return devices.saveDeviceSetMetaData()
}
func (devices *DeviceSet) saveBaseDeviceUUID(baseInfo *devInfo) error {
devices.Lock()
defer devices.Unlock()
if err := devices.activateDeviceIfNeeded(baseInfo, false); err != nil {
return err
}
defer devices.deactivateDevice(baseInfo)
uuid, err := getDeviceUUID(baseInfo.DevName())
if err != nil {
return err
}
devices.BaseDeviceUUID = uuid
return devices.saveDeviceSetMetaData()
}
func (devices *DeviceSet) createBaseImage() error {
logrus.Debug("devmapper: Initializing base device-mapper thin volume")
// Create initial device
info, err := devices.createRegisterDevice("")
if err != nil {
return err
}
logrus.Debug("devmapper: Creating filesystem on base device-mapper thin volume")
if err := devices.activateDeviceIfNeeded(info, false); err != nil {
return err
}
if err := devices.createFilesystem(info); err != nil {
return err
}
info.Initialized = true
if err := devices.saveMetadata(info); err != nil {
info.Initialized = false
return err
}
if err := devices.saveBaseDeviceUUID(info); err != nil {
return fmt.Errorf("devmapper: Could not query and save base device UUID:%v", err)
}
return nil
}
// Returns if thin pool device exists or not. If device exists, also makes
// sure it is a thin pool device and not some other type of device.
func (devices *DeviceSet) thinPoolExists(thinPoolDevice string) (bool, error) {
logrus.Debugf("devmapper: Checking for existence of the pool %s", thinPoolDevice)
info, err := devicemapper.GetInfo(thinPoolDevice)
if err != nil {
return false, fmt.Errorf("devmapper: GetInfo() on device %s failed: %v", thinPoolDevice, err)
}
// Device does not exist.
if info.Exists == 0 {
return false, nil
}
_, _, deviceType, _, err := devicemapper.GetStatus(thinPoolDevice)
if err != nil {
return false, fmt.Errorf("devmapper: GetStatus() on device %s failed: %v", thinPoolDevice, err)
}
if deviceType != "thin-pool" {
return false, fmt.Errorf("devmapper: Device %s is not a thin pool", thinPoolDevice)
}
return true, nil
}
func (devices *DeviceSet) checkThinPool() error {
_, transactionID, dataUsed, _, _, _, err := devices.poolStatus()
if err != nil {
return err
}
if dataUsed != 0 {
return fmt.Errorf("devmapper: Unable to take ownership of thin-pool (%s) that already has used data blocks",
devices.thinPoolDevice)
}
if transactionID != 0 {
return fmt.Errorf("devmapper: Unable to take ownership of thin-pool (%s) with non-zero transaction ID",
devices.thinPoolDevice)
}
return nil
}
// Base image is initialized properly. Either save UUID for first time (for
// upgrade case or verify UUID.
func (devices *DeviceSet) setupVerifyBaseImageUUIDFS(baseInfo *devInfo) error {
// If BaseDeviceUUID is nil (upgrade case), save it and return success.
if devices.BaseDeviceUUID == "" {
if err := devices.saveBaseDeviceUUID(baseInfo); err != nil {
return fmt.Errorf("devmapper: Could not query and save base device UUID:%v", err)
}
return nil
}
if err := devices.verifyBaseDeviceUUIDFS(baseInfo); err != nil {
return fmt.Errorf("devmapper: Base Device UUID and Filesystem verification failed: %v", err)
}
return nil
}
func (devices *DeviceSet) checkGrowBaseDeviceFS(info *devInfo) error {
if !userBaseSize {
return nil
}
if devices.baseFsSize < devices.getBaseDeviceSize() {
return fmt.Errorf("devmapper: Base device size cannot be smaller than %s", units.HumanSize(float64(devices.getBaseDeviceSize())))
}
if devices.baseFsSize == devices.getBaseDeviceSize() {
return nil
}
info.lock.Lock()
defer info.lock.Unlock()
devices.Lock()
defer devices.Unlock()
info.Size = devices.baseFsSize
if err := devices.saveMetadata(info); err != nil {
// Try to remove unused device
delete(devices.Devices, info.Hash)
return err
}
return devices.growFS(info)
}
func (devices *DeviceSet) growFS(info *devInfo) error {
if err := devices.activateDeviceIfNeeded(info, false); err != nil {
return fmt.Errorf("Error activating devmapper device: %s", err)
}
defer devices.deactivateDevice(info)
fsMountPoint := "/run/docker/mnt"
if _, err := os.Stat(fsMountPoint); os.IsNotExist(err) {
if err := os.MkdirAll(fsMountPoint, 0700); err != nil {
return err
}
defer os.RemoveAll(fsMountPoint)
}
options := ""
if devices.BaseDeviceFilesystem == "xfs" {
// XFS needs nouuid or it can't mount filesystems with the same fs
options = joinMountOptions(options, "nouuid")
}
options = joinMountOptions(options, devices.mountOptions)
if err := mount.Mount(info.DevName(), fsMountPoint, devices.BaseDeviceFilesystem, options); err != nil {
return fmt.Errorf("Error mounting '%s' on '%s': %s", info.DevName(), fsMountPoint, err)
}
defer unix.Unmount(fsMountPoint, unix.MNT_DETACH)
switch devices.BaseDeviceFilesystem {
case "ext4":
if out, err := exec.Command("resize2fs", info.DevName()).CombinedOutput(); err != nil {
return fmt.Errorf("Failed to grow rootfs:%v:%s", err, string(out))
}
case "xfs":
if out, err := exec.Command("xfs_growfs", info.DevName()).CombinedOutput(); err != nil {
return fmt.Errorf("Failed to grow rootfs:%v:%s", err, string(out))
}
default:
return fmt.Errorf("Unsupported filesystem type %s", devices.BaseDeviceFilesystem)
}
return nil
}
func (devices *DeviceSet) setupBaseImage() error {
oldInfo, _ := devices.lookupDeviceWithLock("")
// base image already exists. If it is initialized properly, do UUID
// verification and return. Otherwise remove image and set it up
// fresh.
if oldInfo != nil {
if oldInfo.Initialized && !oldInfo.Deleted {
if err := devices.setupVerifyBaseImageUUIDFS(oldInfo); err != nil {
return err
}
if err := devices.checkGrowBaseDeviceFS(oldInfo); err != nil {
return err
}
return nil
}
logrus.Debug("devmapper: Removing uninitialized base image")
// If previous base device is in deferred delete state,
// that needs to be cleaned up first. So don't try
// deferred deletion.
if err := devices.DeleteDevice("", true); err != nil {
return err
}
}
// If we are setting up base image for the first time, make sure
// thin pool is empty.
if devices.thinPoolDevice != "" && oldInfo == nil {
if err := devices.checkThinPool(); err != nil {
return err
}
}
// Create new base image device
if err := devices.createBaseImage(); err != nil {
return err
}
return nil
}
func setCloseOnExec(name string) {
fileInfos, _ := ioutil.ReadDir("/proc/self/fd")
for _, i := range fileInfos {
link, _ := os.Readlink(filepath.Join("/proc/self/fd", i.Name()))
if link == name {
fd, err := strconv.Atoi(i.Name())
if err == nil {
unix.CloseOnExec(fd)
}
}
}
}
func major(device uint64) uint64 {
return (device >> 8) & 0xfff
}
func minor(device uint64) uint64 {
return (device & 0xff) | ((device >> 12) & 0xfff00)
}
// ResizePool increases the size of the pool.
func (devices *DeviceSet) ResizePool(size int64) error {
dirname := devices.loopbackDir()
datafilename := path.Join(dirname, "data")
if len(devices.dataDevice) > 0 {
datafilename = devices.dataDevice
}
metadatafilename := path.Join(dirname, "metadata")
if len(devices.metadataDevice) > 0 {
metadatafilename = devices.metadataDevice
}
datafile, err := os.OpenFile(datafilename, os.O_RDWR, 0)
if datafile == nil {
return err
}
defer datafile.Close()
fi, err := datafile.Stat()
if fi == nil {
return err
}
if fi.Size() > size {
return fmt.Errorf("devmapper: Can't shrink file")
}
dataloopback := loopback.FindLoopDeviceFor(datafile)
if dataloopback == nil {
return fmt.Errorf("devmapper: Unable to find loopback mount for: %s", datafilename)
}
defer dataloopback.Close()
metadatafile, err := os.OpenFile(metadatafilename, os.O_RDWR, 0)
if metadatafile == nil {
return err
}
defer metadatafile.Close()
metadataloopback := loopback.FindLoopDeviceFor(metadatafile)
if metadataloopback == nil {
return fmt.Errorf("devmapper: Unable to find loopback mount for: %s", metadatafilename)
}
defer metadataloopback.Close()
// Grow loopback file
if err := datafile.Truncate(size); err != nil {
return fmt.Errorf("devmapper: Unable to grow loopback file: %s", err)
}
// Reload size for loopback device
if err := loopback.SetCapacity(dataloopback); err != nil {
return fmt.Errorf("Unable to update loopback capacity: %s", err)
}
// Suspend the pool
if err := devicemapper.SuspendDevice(devices.getPoolName()); err != nil {
return fmt.Errorf("devmapper: Unable to suspend pool: %s", err)
}
// Reload with the new block sizes
if err := devicemapper.ReloadPool(devices.getPoolName(), dataloopback, metadataloopback, devices.thinpBlockSize); err != nil {
return fmt.Errorf("devmapper: Unable to reload pool: %s", err)
}
// Resume the pool
if err := devicemapper.ResumeDevice(devices.getPoolName()); err != nil {
return fmt.Errorf("devmapper: Unable to resume pool: %s", err)
}
return nil
}
func (devices *DeviceSet) loadTransactionMetaData() error {
jsonData, err := ioutil.ReadFile(devices.transactionMetaFile())
if err != nil {
// There is no active transaction. This will be the case
// during upgrade.
if os.IsNotExist(err) {
devices.OpenTransactionID = devices.TransactionID
return nil
}
return err
}
json.Unmarshal(jsonData, &devices.transaction)
return nil
}
func (devices *DeviceSet) saveTransactionMetaData() error {
jsonData, err := json.Marshal(&devices.transaction)
if err != nil {
return fmt.Errorf("devmapper: Error encoding metadata to json: %s", err)
}
return devices.writeMetaFile(jsonData, devices.transactionMetaFile())
}
func (devices *DeviceSet) removeTransactionMetaData() error {
return os.RemoveAll(devices.transactionMetaFile())
}
func (devices *DeviceSet) rollbackTransaction() error {
logrus.Debugf("devmapper: Rolling back open transaction: TransactionID=%d hash=%s device_id=%d", devices.OpenTransactionID, devices.DeviceIDHash, devices.DeviceID)
// A device id might have already been deleted before transaction
// closed. In that case this call will fail. Just leave a message
// in case of failure.
if err := devicemapper.DeleteDevice(devices.getPoolDevName(), devices.DeviceID); err != nil {
logrus.Errorf("devmapper: Unable to delete device: %s", err)
}
dinfo := &devInfo{Hash: devices.DeviceIDHash}
if err := devices.removeMetadata(dinfo); err != nil {
logrus.Errorf("devmapper: Unable to remove metadata: %s", err)
} else {
devices.markDeviceIDFree(devices.DeviceID)
}
if err := devices.removeTransactionMetaData(); err != nil {
logrus.Errorf("devmapper: Unable to remove transaction meta file %s: %s", devices.transactionMetaFile(), err)
}
return nil
}
func (devices *DeviceSet) processPendingTransaction() error {
if err := devices.loadTransactionMetaData(); err != nil {
return err
}
// If there was open transaction but pool transaction ID is same
// as open transaction ID, nothing to roll back.
if devices.TransactionID == devices.OpenTransactionID {
return nil
}
// If open transaction ID is less than pool transaction ID, something
// is wrong. Bail out.
if devices.OpenTransactionID < devices.TransactionID {
logrus.Errorf("devmapper: Open Transaction id %d is less than pool transaction id %d", devices.OpenTransactionID, devices.TransactionID)
return nil
}
// Pool transaction ID is not same as open transaction. There is
// a transaction which was not completed.
if err := devices.rollbackTransaction(); err != nil {
return fmt.Errorf("devmapper: Rolling back open transaction failed: %s", err)
}
devices.OpenTransactionID = devices.TransactionID
return nil
}
func (devices *DeviceSet) loadDeviceSetMetaData() error {
jsonData, err := ioutil.ReadFile(devices.deviceSetMetaFile())
if err != nil {
// For backward compatibility return success if file does
// not exist.
if os.IsNotExist(err) {
return nil
}
return err
}
return json.Unmarshal(jsonData, devices)
}
func (devices *DeviceSet) saveDeviceSetMetaData() error {
jsonData, err := json.Marshal(devices)
if err != nil {
return fmt.Errorf("devmapper: Error encoding metadata to json: %s", err)
}
return devices.writeMetaFile(jsonData, devices.deviceSetMetaFile())
}
func (devices *DeviceSet) openTransaction(hash string, DeviceID int) error {
devices.allocateTransactionID()
devices.DeviceIDHash = hash
devices.DeviceID = DeviceID
if err := devices.saveTransactionMetaData(); err != nil {
return fmt.Errorf("devmapper: Error saving transaction metadata: %s", err)
}
return nil
}
func (devices *DeviceSet) refreshTransaction(DeviceID int) error {
devices.DeviceID = DeviceID
if err := devices.saveTransactionMetaData(); err != nil {
return fmt.Errorf("devmapper: Error saving transaction metadata: %s", err)
}
return nil
}
func (devices *DeviceSet) closeTransaction() error {
if err := devices.updatePoolTransactionID(); err != nil {
logrus.Debug("devmapper: Failed to close Transaction")
return err
}
return nil
}
func determineDriverCapabilities(version string) error {
// Kernel driver version >= 4.27.0 support deferred removal
logrus.Debugf("devicemapper: kernel dm driver version is %s", version)
versionSplit := strings.Split(version, ".")
major, err := strconv.Atoi(versionSplit[0])
if err != nil {
return graphdriver.ErrNotSupported
}
if major > 4 {
driverDeferredRemovalSupport = true
return nil
}
if major < 4 {
return nil
}
minor, err := strconv.Atoi(versionSplit[1])
if err != nil {
return graphdriver.ErrNotSupported
}
/*
* If major is 4 and minor is 27, then there is no need to
* check for patch level as it can not be less than 0.
*/
if minor >= 27 {
driverDeferredRemovalSupport = true
return nil
}
return nil
}
// Determine the major and minor number of loopback device
func getDeviceMajorMinor(file *os.File) (uint64, uint64, error) {
var stat unix.Stat_t
err := unix.Stat(file.Name(), &stat)
if err != nil {
return 0, 0, err
}
dev := stat.Rdev
majorNum := major(dev)
minorNum := minor(dev)
logrus.Debugf("devmapper: Major:Minor for device: %s is:%v:%v", file.Name(), majorNum, minorNum)
return majorNum, minorNum, nil
}
// Given a file which is backing file of a loop back device, find the
// loopback device name and its major/minor number.
func getLoopFileDeviceMajMin(filename string) (string, uint64, uint64, error) {
file, err := os.Open(filename)
if err != nil {
logrus.Debugf("devmapper: Failed to open file %s", filename)
return "", 0, 0, err
}
defer file.Close()
loopbackDevice := loopback.FindLoopDeviceFor(file)
if loopbackDevice == nil {
return "", 0, 0, fmt.Errorf("devmapper: Unable to find loopback mount for: %s", filename)
}
defer loopbackDevice.Close()
Major, Minor, err := getDeviceMajorMinor(loopbackDevice)
if err != nil {
return "", 0, 0, err
}
return loopbackDevice.Name(), Major, Minor, nil
}
// Get the major/minor numbers of thin pool data and metadata devices
func (devices *DeviceSet) getThinPoolDataMetaMajMin() (uint64, uint64, uint64, uint64, error) {
var params, poolDataMajMin, poolMetadataMajMin string
_, _, _, params, err := devicemapper.GetTable(devices.getPoolName())
if err != nil {
return 0, 0, 0, 0, err
}
if _, err = fmt.Sscanf(params, "%s %s", &poolMetadataMajMin, &poolDataMajMin); err != nil {
return 0, 0, 0, 0, err
}
logrus.Debugf("devmapper: poolDataMajMin=%s poolMetaMajMin=%s\n", poolDataMajMin, poolMetadataMajMin)
poolDataMajMinorSplit := strings.Split(poolDataMajMin, ":")
poolDataMajor, err := strconv.ParseUint(poolDataMajMinorSplit[0], 10, 32)
if err != nil {
return 0, 0, 0, 0, err
}
poolDataMinor, err := strconv.ParseUint(poolDataMajMinorSplit[1], 10, 32)
if err != nil {
return 0, 0, 0, 0, err
}
poolMetadataMajMinorSplit := strings.Split(poolMetadataMajMin, ":")
poolMetadataMajor, err := strconv.ParseUint(poolMetadataMajMinorSplit[0], 10, 32)
if err != nil {
return 0, 0, 0, 0, err
}
poolMetadataMinor, err := strconv.ParseUint(poolMetadataMajMinorSplit[1], 10, 32)
if err != nil {
return 0, 0, 0, 0, err
}
return poolDataMajor, poolDataMinor, poolMetadataMajor, poolMetadataMinor, nil
}
func (devices *DeviceSet) loadThinPoolLoopBackInfo() error {
poolDataMajor, poolDataMinor, poolMetadataMajor, poolMetadataMinor, err := devices.getThinPoolDataMetaMajMin()
if err != nil {
return err
}
dirname := devices.loopbackDir()
// data device has not been passed in. So there should be a data file
// which is being mounted as loop device.
if devices.dataDevice == "" {
datafilename := path.Join(dirname, "data")
dataLoopDevice, dataMajor, dataMinor, err := getLoopFileDeviceMajMin(datafilename)
if err != nil {
return err
}
// Compare the two
if poolDataMajor == dataMajor && poolDataMinor == dataMinor {
devices.dataDevice = dataLoopDevice
devices.dataLoopFile = datafilename
}
}
// metadata device has not been passed in. So there should be a
// metadata file which is being mounted as loop device.
if devices.metadataDevice == "" {
metadatafilename := path.Join(dirname, "metadata")
metadataLoopDevice, metadataMajor, metadataMinor, err := getLoopFileDeviceMajMin(metadatafilename)
if err != nil {
return err
}
if poolMetadataMajor == metadataMajor && poolMetadataMinor == metadataMinor {
devices.metadataDevice = metadataLoopDevice
devices.metadataLoopFile = metadatafilename
}
}
return nil
}
func (devices *DeviceSet) enableDeferredRemovalDeletion() error {
// If user asked for deferred removal then check both libdm library
// and kernel driver support deferred removal otherwise error out.
if enableDeferredRemoval {
if !driverDeferredRemovalSupport {
return fmt.Errorf("devmapper: Deferred removal can not be enabled as kernel does not support it")
}
if !devicemapper.LibraryDeferredRemovalSupport {
return fmt.Errorf("devmapper: Deferred removal can not be enabled as libdm does not support it")
}
logrus.Debug("devmapper: Deferred removal support enabled.")
devices.deferredRemove = true
}
if enableDeferredDeletion {
if !devices.deferredRemove {
return fmt.Errorf("devmapper: Deferred deletion can not be enabled as deferred removal is not enabled. Enable deferred removal using --storage-opt dm.use_deferred_removal=true parameter")
}
logrus.Debug("devmapper: Deferred deletion support enabled.")
devices.deferredDelete = true
}
return nil
}
func (devices *DeviceSet) initDevmapper(doInit bool) (retErr error) {
if err := devices.enableDeferredRemovalDeletion(); err != nil {
return err
}
// https://github.com/docker/docker/issues/4036
if supported := devicemapper.UdevSetSyncSupport(true); !supported {
if dockerversion.IAmStatic == "true" {
logrus.Error("devmapper: Udev sync is not supported. This will lead to data loss and unexpected behavior. Install a dynamic binary to use devicemapper or select a different storage driver. For more information, see https://docs.docker.com/engine/reference/commandline/dockerd/#storage-driver-options")
} else {
logrus.Error("devmapper: Udev sync is not supported. This will lead to data loss and unexpected behavior. Install a more recent version of libdevmapper or select a different storage driver. For more information, see https://docs.docker.com/engine/reference/commandline/dockerd/#storage-driver-options")
}
if !devices.overrideUdevSyncCheck {
return graphdriver.ErrNotSupported
}
}
//create the root dir of the devmapper driver ownership to match this
//daemon's remapped root uid/gid so containers can start properly
uid, gid, err := idtools.GetRootUIDGID(devices.uidMaps, devices.gidMaps)
if err != nil {
return err
}
if err := idtools.MkdirAs(devices.root, 0700, uid, gid); err != nil && !os.IsExist(err) {
return err
}
if err := os.MkdirAll(devices.metadataDir(), 0700); err != nil && !os.IsExist(err) {
return err
}
prevSetupConfig, err := readLVMConfig(devices.root)
if err != nil {
return err
}
if !reflect.DeepEqual(devices.lvmSetupConfig, directLVMConfig{}) {
if devices.thinPoolDevice != "" {
return errors.New("cannot setup direct-lvm when `dm.thinpooldev` is also specified")
}
if !reflect.DeepEqual(prevSetupConfig, devices.lvmSetupConfig) {
if !reflect.DeepEqual(prevSetupConfig, directLVMConfig{}) {
return errors.New("changing direct-lvm config is not supported")
}
logrus.WithField("storage-driver", "devicemapper").WithField("direct-lvm-config", devices.lvmSetupConfig).Debugf("Setting up direct lvm mode")
if err := verifyBlockDevice(devices.lvmSetupConfig.Device, lvmSetupConfigForce); err != nil {
return err
}
if err := setupDirectLVM(devices.lvmSetupConfig); err != nil {
return err
}
if err := writeLVMConfig(devices.root, devices.lvmSetupConfig); err != nil {
return err
}
}
devices.thinPoolDevice = "docker-thinpool"
logrus.WithField("storage-driver", "devicemapper").Debugf("Setting dm.thinpooldev to %q", devices.thinPoolDevice)
}
// Set the device prefix from the device id and inode of the docker root dir
var st unix.Stat_t
if err := unix.Stat(devices.root, &st); err != nil {
return fmt.Errorf("devmapper: Error looking up dir %s: %s", devices.root, err)
}
// "reg-" stands for "regular file".
// In the future we might use "dev-" for "device file", etc.
// docker-maj,min[-inode] stands for:
// - Managed by docker
// - The target of this device is at major <maj> and minor <min>
// - If <inode> is defined, use that file inside the device as a loopback image. Otherwise use the device itself.
devices.devicePrefix = fmt.Sprintf("docker-%d:%d-%d", major(st.Dev), minor(st.Dev), st.Ino)
logrus.Debugf("devmapper: Generated prefix: %s", devices.devicePrefix)
// Check for the existence of the thin-pool device
poolExists, err := devices.thinPoolExists(devices.getPoolName())
if err != nil {
return err
}
// It seems libdevmapper opens this without O_CLOEXEC, and go exec will not close files
// that are not Close-on-exec,
// so we add this badhack to make sure it closes itself
setCloseOnExec("/dev/mapper/control")
// Make sure the sparse images exist in <root>/devicemapper/data and
// <root>/devicemapper/metadata
createdLoopback := false
// If the pool doesn't exist, create it
if !poolExists && devices.thinPoolDevice == "" {
logrus.Debug("devmapper: Pool doesn't exist. Creating it.")
var (
dataFile *os.File
metadataFile *os.File
)
if devices.dataDevice == "" {
// Make sure the sparse images exist in <root>/devicemapper/data
hasData := devices.hasImage("data")
if !doInit && !hasData {
return errors.New("loopback data file not found")
}
if !hasData {
createdLoopback = true
}
data, err := devices.ensureImage("data", devices.dataLoopbackSize)
if err != nil {
logrus.Debugf("devmapper: Error device ensureImage (data): %s", err)
return err
}
dataFile, err = loopback.AttachLoopDevice(data)
if err != nil {
return err
}
devices.dataLoopFile = data
devices.dataDevice = dataFile.Name()
} else {
dataFile, err = os.OpenFile(devices.dataDevice, os.O_RDWR, 0600)
if err != nil {
return err
}
}
defer dataFile.Close()
if devices.metadataDevice == "" {
// Make sure the sparse images exist in <root>/devicemapper/metadata
hasMetadata := devices.hasImage("metadata")
if !doInit && !hasMetadata {
return errors.New("loopback metadata file not found")
}
if !hasMetadata {
createdLoopback = true
}
metadata, err := devices.ensureImage("metadata", devices.metaDataLoopbackSize)
if err != nil {
logrus.Debugf("devmapper: Error device ensureImage (metadata): %s", err)
return err
}
metadataFile, err = loopback.AttachLoopDevice(metadata)
if err != nil {
return err
}
devices.metadataLoopFile = metadata
devices.metadataDevice = metadataFile.Name()
} else {
metadataFile, err = os.OpenFile(devices.metadataDevice, os.O_RDWR, 0600)
if err != nil {
return err
}
}
defer metadataFile.Close()
if err := devicemapper.CreatePool(devices.getPoolName(), dataFile, metadataFile, devices.thinpBlockSize); err != nil {
return err
}
defer func() {
if retErr != nil {
err = devices.deactivatePool()
if err != nil {
logrus.Warnf("devmapper: Failed to deactivatePool: %v", err)
}
}
}()
}
// Pool already exists and caller did not pass us a pool. That means
// we probably created pool earlier and could not remove it as some
// containers were still using it. Detect some of the properties of
// pool, like is it using loop devices.
if poolExists && devices.thinPoolDevice == "" {
if err := devices.loadThinPoolLoopBackInfo(); err != nil {
logrus.Debugf("devmapper: Failed to load thin pool loopback device information:%v", err)
return err
}
}
// If we didn't just create the data or metadata image, we need to
// load the transaction id and migrate old metadata
if !createdLoopback {
if err := devices.initMetaData(); err != nil {
return err
}
}
if devices.thinPoolDevice == "" {
if devices.metadataLoopFile != "" || devices.dataLoopFile != "" {
logrus.Warn("devmapper: Usage of loopback devices is strongly discouraged for production use. Please use `--storage-opt dm.thinpooldev` or use `man dockerd` to refer to dm.thinpooldev section.")
}
}
// Right now this loads only NextDeviceID. If there is more metadata
// down the line, we might have to move it earlier.
if err := devices.loadDeviceSetMetaData(); err != nil {
return err
}
// Setup the base image
if doInit {
if err := devices.setupBaseImage(); err != nil {
logrus.Debugf("devmapper: Error device setupBaseImage: %s", err)
return err
}
}
return nil
}
// AddDevice adds a device and registers in the hash.
func (devices *DeviceSet) AddDevice(hash, baseHash string, storageOpt map[string]string) error {
logrus.Debugf("devmapper: AddDevice START(hash=%s basehash=%s)", hash, baseHash)
defer logrus.Debugf("devmapper: AddDevice END(hash=%s basehash=%s)", hash, baseHash)
// If a deleted device exists, return error.
baseInfo, err := devices.lookupDeviceWithLock(baseHash)
if err != nil {
return err
}
if baseInfo.Deleted {
return fmt.Errorf("devmapper: Base device %v has been marked for deferred deletion", baseInfo.Hash)
}
baseInfo.lock.Lock()
defer baseInfo.lock.Unlock()
devices.Lock()
defer devices.Unlock()
// Also include deleted devices in case hash of new device is
// same as one of the deleted devices.
if info, _ := devices.lookupDevice(hash); info != nil {
return fmt.Errorf("devmapper: device %s already exists. Deleted=%v", hash, info.Deleted)
}
size, err := devices.parseStorageOpt(storageOpt)
if err != nil {
return err
}
if size == 0 {
size = baseInfo.Size
}
if size < baseInfo.Size {
return fmt.Errorf("devmapper: Container size cannot be smaller than %s", units.HumanSize(float64(baseInfo.Size)))
}
if err := devices.takeSnapshot(hash, baseInfo, size); err != nil {
return err
}
// Grow the container rootfs.
if size > baseInfo.Size {
info, err := devices.lookupDevice(hash)
if err != nil {
return err
}
if err := devices.growFS(info); err != nil {
return err
}
}
return nil
}
func (devices *DeviceSet) parseStorageOpt(storageOpt map[string]string) (uint64, error) {
// 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 0, err
}
return uint64(size), nil
default:
return 0, fmt.Errorf("Unknown option %s", key)
}
}
return 0, nil
}
func (devices *DeviceSet) markForDeferredDeletion(info *devInfo) error {
// If device is already in deleted state, there is nothing to be done.
if info.Deleted {
return nil
}
logrus.Debugf("devmapper: Marking device %s for deferred deletion.", info.Hash)
info.Deleted = true
// save device metadata to reflect deleted state.
if err := devices.saveMetadata(info); err != nil {
info.Deleted = false
return err
}
devices.nrDeletedDevices++
return nil
}
// Should be called with devices.Lock() held.
func (devices *DeviceSet) deleteTransaction(info *devInfo, syncDelete bool) error {
if err := devices.openTransaction(info.Hash, info.DeviceID); err != nil {
logrus.Debugf("devmapper: Error opening transaction hash = %s deviceId = %d", "", info.DeviceID)
return err
}
defer devices.closeTransaction()
err := devicemapper.DeleteDevice(devices.getPoolDevName(), info.DeviceID)
if err != nil {
// If syncDelete is true, we want to return error. If deferred
// deletion is not enabled, we return an error. If error is
// something other then EBUSY, return an error.
if syncDelete || !devices.deferredDelete || err != devicemapper.ErrBusy {
logrus.Debugf("devmapper: Error deleting device: %s", err)
return err
}
}
if err == nil {
if err := devices.unregisterDevice(info.Hash); err != nil {
return err
}
// If device was already in deferred delete state that means
// deletion was being tried again later. Reduce the deleted
// device count.
if info.Deleted {
devices.nrDeletedDevices--
}
devices.markDeviceIDFree(info.DeviceID)
} else {
if err := devices.markForDeferredDeletion(info); err != nil {
return err
}
}
return nil
}
// Issue discard only if device open count is zero.
func (devices *DeviceSet) issueDiscard(info *devInfo) error {
logrus.Debugf("devmapper: issueDiscard START(device: %s).", info.Hash)
defer logrus.Debugf("devmapper: issueDiscard END(device: %s).", info.Hash)
// This is a workaround for the kernel not discarding block so
// on the thin pool when we remove a thinp device, so we do it
// manually.
// Even if device is deferred deleted, activate it and issue
// discards.
if err := devices.activateDeviceIfNeeded(info, true); err != nil {
return err
}
devinfo, err := devicemapper.GetInfo(info.Name())
if err != nil {
return err
}
if devinfo.OpenCount != 0 {
logrus.Debugf("devmapper: Device: %s is in use. OpenCount=%d. Not issuing discards.", info.Hash, devinfo.OpenCount)
return nil
}
if err := devicemapper.BlockDeviceDiscard(info.DevName()); err != nil {
logrus.Debugf("devmapper: Error discarding block on device: %s (ignoring)", err)
}
return nil
}
// Should be called with devices.Lock() held.
func (devices *DeviceSet) deleteDevice(info *devInfo, syncDelete bool) error {
if devices.doBlkDiscard {
devices.issueDiscard(info)
}
// Try to deactivate device in case it is active.
// If deferred removal is enabled and deferred deletion is disabled
// then make sure device is removed synchronously. There have been
// some cases of device being busy for short duration and we would
// rather busy wait for device removal to take care of these cases.
deferredRemove := devices.deferredRemove
if !devices.deferredDelete {
deferredRemove = false
}
if err := devices.deactivateDeviceMode(info, deferredRemove); err != nil {
logrus.Debugf("devmapper: Error deactivating device: %s", err)
return err
}
if err := devices.deleteTransaction(info, syncDelete); err != nil {
return err
}
return nil
}
// DeleteDevice will return success if device has been marked for deferred
// removal. If one wants to override that and want DeleteDevice() to fail if
// device was busy and could not be deleted, set syncDelete=true.
func (devices *DeviceSet) DeleteDevice(hash string, syncDelete bool) error {
logrus.Debugf("devmapper: DeleteDevice START(hash=%v syncDelete=%v)", hash, syncDelete)
defer logrus.Debugf("devmapper: DeleteDevice END(hash=%v syncDelete=%v)", hash, syncDelete)
info, err := devices.lookupDeviceWithLock(hash)
if err != nil {
return err
}
info.lock.Lock()
defer info.lock.Unlock()
devices.Lock()
defer devices.Unlock()
return devices.deleteDevice(info, syncDelete)
}
func (devices *DeviceSet) deactivatePool() error {
logrus.Debug("devmapper: deactivatePool() START")
defer logrus.Debug("devmapper: deactivatePool() END")
devname := devices.getPoolDevName()
devinfo, err := devicemapper.GetInfo(devname)
if err != nil {
return err
}
if devinfo.Exists == 0 {
return nil
}
if err := devicemapper.RemoveDevice(devname); err != nil {
return err
}
if d, err := devicemapper.GetDeps(devname); err == nil {
logrus.Warnf("devmapper: device %s still has %d active dependents", devname, d.Count)
}
return nil
}
func (devices *DeviceSet) deactivateDevice(info *devInfo) error {
return devices.deactivateDeviceMode(info, devices.deferredRemove)
}
func (devices *DeviceSet) deactivateDeviceMode(info *devInfo, deferredRemove bool) error {
var err error
logrus.Debugf("devmapper: deactivateDevice START(%s)", info.Hash)
defer logrus.Debugf("devmapper: deactivateDevice END(%s)", info.Hash)
devinfo, err := devicemapper.GetInfo(info.Name())
if err != nil {
return err
}
if devinfo.Exists == 0 {
return nil
}
if deferredRemove {
err = devicemapper.RemoveDeviceDeferred(info.Name())
} else {
err = devices.removeDevice(info.Name())
}
// This function's semantics is such that it does not return an
// error if device does not exist. So if device went away by
// the time we actually tried to remove it, do not return error.
if err != devicemapper.ErrEnxio {
return err
}
return nil
}
// Issues the underlying dm remove operation.
func (devices *DeviceSet) removeDevice(devname string) error {
var err error
logrus.Debugf("devmapper: removeDevice START(%s)", devname)
defer logrus.Debugf("devmapper: removeDevice END(%s)", devname)
for i := 0; i < 200; i++ {
err = devicemapper.RemoveDevice(devname)
if err == nil {
break
}
if err != devicemapper.ErrBusy {
return err
}
// If we see EBUSY it may be a transient error,
// sleep a bit a retry a few times.
devices.Unlock()
time.Sleep(100 * time.Millisecond)
devices.Lock()
}
return err
}
func (devices *DeviceSet) cancelDeferredRemovalIfNeeded(info *devInfo) error {
if !devices.deferredRemove {
return nil
}
logrus.Debugf("devmapper: cancelDeferredRemovalIfNeeded START(%s)", info.Name())
defer logrus.Debugf("devmapper: cancelDeferredRemovalIfNeeded END(%s)", info.Name())
devinfo, err := devicemapper.GetInfoWithDeferred(info.Name())
if err != nil {
return err
}
if devinfo != nil && devinfo.DeferredRemove == 0 {
return nil
}
// Cancel deferred remove
if err := devices.cancelDeferredRemoval(info); err != nil {
// If Error is ErrEnxio. Device is probably already gone. Continue.
if err != devicemapper.ErrEnxio {
return err
}
}
return nil
}
func (devices *DeviceSet) cancelDeferredRemoval(info *devInfo) error {
logrus.Debugf("devmapper: cancelDeferredRemoval START(%s)", info.Name())
defer logrus.Debugf("devmapper: cancelDeferredRemoval END(%s)", info.Name())
var err error
// Cancel deferred remove
for i := 0; i < 100; i++ {
err = devicemapper.CancelDeferredRemove(info.Name())
if err != nil {
if err == devicemapper.ErrBusy {
// If we see EBUSY it may be a transient error,
// sleep a bit a retry a few times.
devices.Unlock()
time.Sleep(100 * time.Millisecond)
devices.Lock()
continue
}
}
break
}
return err
}
// Shutdown shuts down the device by unmounting the root.
func (devices *DeviceSet) Shutdown(home string) error {
logrus.Debugf("devmapper: [deviceset %s] Shutdown()", devices.devicePrefix)
logrus.Debugf("devmapper: Shutting down DeviceSet: %s", devices.root)
defer logrus.Debugf("devmapper: [deviceset %s] Shutdown() END", devices.devicePrefix)
// Stop deletion worker. This should start delivering new events to
// ticker channel. That means no new instance of cleanupDeletedDevice()
// will run after this call. If one instance is already running at
// the time of the call, it must be holding devices.Lock() and
// we will block on this lock till cleanup function exits.
devices.deletionWorkerTicker.Stop()
devices.Lock()
// Save DeviceSet Metadata first. Docker kills all threads if they
// don't finish in certain time. It is possible that Shutdown()
// routine does not finish in time as we loop trying to deactivate
// some devices while these are busy. In that case shutdown() routine
// will be killed and we will not get a chance to save deviceset
// metadata. Hence save this early before trying to deactivate devices.
devices.saveDeviceSetMetaData()
// ignore the error since it's just a best effort to not try to unmount something that's mounted
mounts, _ := mount.GetMounts()
mounted := make(map[string]bool, len(mounts))
for _, mnt := range mounts {
mounted[mnt.Mountpoint] = true
}
if err := filepath.Walk(path.Join(home, "mnt"), func(p string, info os.FileInfo, err error) error {
if err != nil {
return err
}
if !info.IsDir() {
return nil
}
if mounted[p] {
// We use MNT_DETACH here in case it is still busy in some running
// container. This means it'll go away from the global scope directly,
// and the device will be released when that container dies.
if err := unix.Unmount(p, unix.MNT_DETACH); err != nil {
logrus.Debugf("devmapper: Shutdown unmounting %s, error: %s", p, err)
}
}
if devInfo, err := devices.lookupDevice(path.Base(p)); err != nil {
logrus.Debugf("devmapper: Shutdown lookup device %s, error: %s", path.Base(p), err)
} else {
if err := devices.deactivateDevice(devInfo); err != nil {
logrus.Debugf("devmapper: Shutdown deactivate %s , error: %s", devInfo.Hash, err)
}
}
return nil
}); err != nil && !os.IsNotExist(err) {
devices.Unlock()
return err
}
devices.Unlock()
info, _ := devices.lookupDeviceWithLock("")
if info != nil {
info.lock.Lock()
devices.Lock()
if err := devices.deactivateDevice(info); err != nil {
logrus.Debugf("devmapper: Shutdown deactivate base , error: %s", err)
}
devices.Unlock()
info.lock.Unlock()
}
devices.Lock()
if devices.thinPoolDevice == "" {
if err := devices.deactivatePool(); err != nil {
logrus.Debugf("devmapper: Shutdown deactivate pool , error: %s", err)
}
}
devices.Unlock()
return nil
}
// Recent XFS changes allow changing behavior of filesystem in case of errors.
// When thin pool gets full and XFS gets ENOSPC error, currently it tries
// IO infinitely and sometimes it can block the container process
// and process can't be killWith 0 value, XFS will not retry upon error
// and instead will shutdown filesystem.
func (devices *DeviceSet) xfsSetNospaceRetries(info *devInfo) error {
dmDevicePath, err := os.Readlink(info.DevName())
if err != nil {
return fmt.Errorf("devmapper: readlink failed for device %v:%v", info.DevName(), err)
}
dmDeviceName := path.Base(dmDevicePath)
filePath := "/sys/fs/xfs/" + dmDeviceName + "/error/metadata/ENOSPC/max_retries"
maxRetriesFile, err := os.OpenFile(filePath, os.O_WRONLY, 0)
if err != nil {
return fmt.Errorf("devmapper: user specified daemon option dm.xfs_nospace_max_retries but it does not seem to be supported on this system :%v", err)
}
defer maxRetriesFile.Close()
// Set max retries to 0
_, err = maxRetriesFile.WriteString(devices.xfsNospaceRetries)
if err != nil {
return fmt.Errorf("devmapper: Failed to write string %v to file %v:%v", devices.xfsNospaceRetries, filePath, err)
}
return nil
}
// MountDevice mounts the device if not already mounted.
func (devices *DeviceSet) MountDevice(hash, path, mountLabel string) error {
info, err := devices.lookupDeviceWithLock(hash)
if err != nil {
return err
}
if info.Deleted {
return fmt.Errorf("devmapper: Can't mount device %v as it has been marked for deferred deletion", info.Hash)
}
info.lock.Lock()
defer info.lock.Unlock()
devices.Lock()
defer devices.Unlock()
if err := devices.activateDeviceIfNeeded(info, false); err != nil {
return fmt.Errorf("devmapper: Error activating devmapper device for '%s': %s", hash, err)
}
fstype, err := ProbeFsType(info.DevName())
if err != nil {
return err
}
options := ""
if fstype == "xfs" {
// XFS needs nouuid or it can't mount filesystems with the same fs
options = joinMountOptions(options, "nouuid")
}
options = joinMountOptions(options, devices.mountOptions)
options = joinMountOptions(options, label.FormatMountLabel("", mountLabel))
if err := mount.Mount(info.DevName(), path, fstype, options); err != nil {
return fmt.Errorf("devmapper: Error mounting '%s' on '%s': %s", info.DevName(), path, err)
}
if fstype == "xfs" && devices.xfsNospaceRetries != "" {
if err := devices.xfsSetNospaceRetries(info); err != nil {
unix.Unmount(path, unix.MNT_DETACH)
devices.deactivateDevice(info)
return err
}
}
return nil
}
// UnmountDevice unmounts the device and removes it from hash.
func (devices *DeviceSet) UnmountDevice(hash, mountPath string) error {
logrus.Debugf("devmapper: UnmountDevice START(hash=%s)", hash)
defer logrus.Debugf("devmapper: UnmountDevice END(hash=%s)", hash)
info, err := devices.lookupDeviceWithLock(hash)
if err != nil {
return err
}
info.lock.Lock()
defer info.lock.Unlock()
devices.Lock()
defer devices.Unlock()
logrus.Debugf("devmapper: Unmount(%s)", mountPath)
if err := unix.Unmount(mountPath, unix.MNT_DETACH); err != nil {
return err
}
logrus.Debug("devmapper: Unmount done")
return devices.deactivateDevice(info)
}
// HasDevice returns true if the device metadata exists.
func (devices *DeviceSet) HasDevice(hash string) bool {
info, _ := devices.lookupDeviceWithLock(hash)
return info != nil
}
// List returns a list of device ids.
func (devices *DeviceSet) List() []string {
devices.Lock()
defer devices.Unlock()
ids := make([]string, len(devices.Devices))
i := 0
for k := range devices.Devices {
ids[i] = k
i++
}
return ids
}
func (devices *DeviceSet) deviceStatus(devName string) (sizeInSectors, mappedSectors, highestMappedSector uint64, err error) {
var params string
_, sizeInSectors, _, params, err = devicemapper.GetStatus(devName)
if err != nil {
return
}
if _, err = fmt.Sscanf(params, "%d %d", &mappedSectors, &highestMappedSector); err == nil {
return
}
return
}
// GetDeviceStatus provides size, mapped sectors
func (devices *DeviceSet) GetDeviceStatus(hash string) (*DevStatus, error) {
info, err := devices.lookupDeviceWithLock(hash)
if err != nil {
return nil, err
}
info.lock.Lock()
defer info.lock.Unlock()
devices.Lock()
defer devices.Unlock()
status := &DevStatus{
DeviceID: info.DeviceID,
Size: info.Size,
TransactionID: info.TransactionID,
}
if err := devices.activateDeviceIfNeeded(info, false); err != nil {
return nil, fmt.Errorf("devmapper: Error activating devmapper device for '%s': %s", hash, err)
}
sizeInSectors, mappedSectors, highestMappedSector, err := devices.deviceStatus(info.DevName())
if err != nil {
return nil, err
}
status.SizeInSectors = sizeInSectors
status.MappedSectors = mappedSectors
status.HighestMappedSector = highestMappedSector
return status, nil
}
func (devices *DeviceSet) poolStatus() (totalSizeInSectors, transactionID, dataUsed, dataTotal, metadataUsed, metadataTotal uint64, err error) {
var params string
if _, totalSizeInSectors, _, params, err = devicemapper.GetStatus(devices.getPoolName()); err == nil {
_, err = fmt.Sscanf(params, "%d %d/%d %d/%d", &transactionID, &metadataUsed, &metadataTotal, &dataUsed, &dataTotal)
}
return
}
// DataDevicePath returns the path to the data storage for this deviceset,
// regardless of loopback or block device
func (devices *DeviceSet) DataDevicePath() string {
return devices.dataDevice
}
// MetadataDevicePath returns the path to the metadata storage for this deviceset,
// regardless of loopback or block device
func (devices *DeviceSet) MetadataDevicePath() string {
return devices.metadataDevice
}
func (devices *DeviceSet) getUnderlyingAvailableSpace(loopFile string) (uint64, error) {
buf := new(unix.Statfs_t)
if err := unix.Statfs(loopFile, buf); err != nil {
logrus.Warnf("devmapper: Couldn't stat loopfile filesystem %v: %v", loopFile, err)
return 0, err
}
return buf.Bfree * uint64(buf.Bsize), nil
}
func (devices *DeviceSet) isRealFile(loopFile string) (bool, error) {
if loopFile != "" {
fi, err := os.Stat(loopFile)
if err != nil {
logrus.Warnf("devmapper: Couldn't stat loopfile %v: %v", loopFile, err)
return false, err
}
return fi.Mode().IsRegular(), nil
}
return false, nil
}
// Status returns the current status of this deviceset
func (devices *DeviceSet) Status() *Status {
devices.Lock()
defer devices.Unlock()
status := &Status{}
status.PoolName = devices.getPoolName()
status.DataFile = devices.DataDevicePath()
status.DataLoopback = devices.dataLoopFile
status.MetadataFile = devices.MetadataDevicePath()
status.MetadataLoopback = devices.metadataLoopFile
status.UdevSyncSupported = devicemapper.UdevSyncSupported()
status.DeferredRemoveEnabled = devices.deferredRemove
status.DeferredDeleteEnabled = devices.deferredDelete
status.DeferredDeletedDeviceCount = devices.nrDeletedDevices
status.BaseDeviceSize = devices.getBaseDeviceSize()
status.BaseDeviceFS = devices.getBaseDeviceFS()
totalSizeInSectors, _, dataUsed, dataTotal, metadataUsed, metadataTotal, err := devices.poolStatus()
if err == nil {
// Convert from blocks to bytes
blockSizeInSectors := totalSizeInSectors / dataTotal
status.Data.Used = dataUsed * blockSizeInSectors * 512
status.Data.Total = dataTotal * blockSizeInSectors * 512
status.Data.Available = status.Data.Total - status.Data.Used
// metadata blocks are always 4k
status.Metadata.Used = metadataUsed * 4096
status.Metadata.Total = metadataTotal * 4096
status.Metadata.Available = status.Metadata.Total - status.Metadata.Used
status.SectorSize = blockSizeInSectors * 512
if check, _ := devices.isRealFile(devices.dataLoopFile); check {
actualSpace, err := devices.getUnderlyingAvailableSpace(devices.dataLoopFile)
if err == nil && actualSpace < status.Data.Available {
status.Data.Available = actualSpace
}
}
if check, _ := devices.isRealFile(devices.metadataLoopFile); check {
actualSpace, err := devices.getUnderlyingAvailableSpace(devices.metadataLoopFile)
if err == nil && actualSpace < status.Metadata.Available {
status.Metadata.Available = actualSpace
}
}
minFreeData := (dataTotal * uint64(devices.minFreeSpacePercent)) / 100
status.MinFreeSpace = minFreeData * blockSizeInSectors * 512
}
return status
}
// Status returns the current status of this deviceset
func (devices *DeviceSet) exportDeviceMetadata(hash string) (*deviceMetadata, error) {
info, err := devices.lookupDeviceWithLock(hash)
if err != nil {
return nil, err
}
info.lock.Lock()
defer info.lock.Unlock()
metadata := &deviceMetadata{info.DeviceID, info.Size, info.Name()}
return metadata, nil
}
// NewDeviceSet creates the device set based on the options provided.
func NewDeviceSet(root string, doInit bool, options []string, uidMaps, gidMaps []idtools.IDMap) (*DeviceSet, error) {
devicemapper.SetDevDir("/dev")
devices := &DeviceSet{
root: root,
metaData: metaData{Devices: make(map[string]*devInfo)},
dataLoopbackSize: defaultDataLoopbackSize,
metaDataLoopbackSize: defaultMetaDataLoopbackSize,
baseFsSize: defaultBaseFsSize,
overrideUdevSyncCheck: defaultUdevSyncOverride,
doBlkDiscard: true,
thinpBlockSize: defaultThinpBlockSize,
deviceIDMap: make([]byte, deviceIDMapSz),
deletionWorkerTicker: time.NewTicker(time.Second * 30),
uidMaps: uidMaps,
gidMaps: gidMaps,
minFreeSpacePercent: defaultMinFreeSpacePercent,
}
version, err := devicemapper.GetDriverVersion()
if err != nil {
// Can't even get driver version, assume not supported
return nil, graphdriver.ErrNotSupported
}
if err := determineDriverCapabilities(version); err != nil {
return nil, graphdriver.ErrNotSupported
}
if driverDeferredRemovalSupport && devicemapper.LibraryDeferredRemovalSupport {
// enable deferred stuff by default
enableDeferredDeletion = true
enableDeferredRemoval = true
}
foundBlkDiscard := false
var lvmSetupConfig directLVMConfig
for _, option := range options {
key, val, err := parsers.ParseKeyValueOpt(option)
if err != nil {
return nil, err
}
key = strings.ToLower(key)
switch key {
case "dm.basesize":
size, err := units.RAMInBytes(val)
if err != nil {
return nil, err
}
userBaseSize = true
devices.baseFsSize = uint64(size)
case "dm.loopdatasize":
size, err := units.RAMInBytes(val)
if err != nil {
return nil, err
}
devices.dataLoopbackSize = size
case "dm.loopmetadatasize":
size, err := units.RAMInBytes(val)
if err != nil {
return nil, err
}
devices.metaDataLoopbackSize = size
case "dm.fs":
if val != "ext4" && val != "xfs" {
return nil, fmt.Errorf("devmapper: Unsupported filesystem %s", val)
}
devices.filesystem = val
case "dm.mkfsarg":
devices.mkfsArgs = append(devices.mkfsArgs, val)
case "dm.mountopt":
devices.mountOptions = joinMountOptions(devices.mountOptions, val)
case "dm.metadatadev":
devices.metadataDevice = val
case "dm.datadev":
devices.dataDevice = val
case "dm.thinpooldev":
devices.thinPoolDevice = strings.TrimPrefix(val, "/dev/mapper/")
case "dm.blkdiscard":
foundBlkDiscard = true
devices.doBlkDiscard, err = strconv.ParseBool(val)
if err != nil {
return nil, err
}
case "dm.blocksize":
size, err := units.RAMInBytes(val)
if err != nil {
return nil, err
}
// convert to 512b sectors
devices.thinpBlockSize = uint32(size) >> 9
case "dm.override_udev_sync_check":
devices.overrideUdevSyncCheck, err = strconv.ParseBool(val)
if err != nil {
return nil, err
}
case "dm.use_deferred_removal":
enableDeferredRemoval, err = strconv.ParseBool(val)
if err != nil {
return nil, err
}
case "dm.use_deferred_deletion":
enableDeferredDeletion, err = strconv.ParseBool(val)
if err != nil {
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)
case "dm.xfs_nospace_max_retries":
_, err := strconv.ParseUint(val, 10, 64)
if err != nil {
return nil, err
}
devices.xfsNospaceRetries = val
case "dm.directlvm_device":
lvmSetupConfig.Device = val
case "dm.directlvm_device_force":
lvmSetupConfigForce, err = strconv.ParseBool(val)
if err != nil {
return nil, err
}
case "dm.thinp_percent":
per, err := strconv.ParseUint(strings.TrimSuffix(val, "%"), 10, 32)
if err != nil {
return nil, errors.Wrapf(err, "could not parse `dm.thinp_percent=%s`", val)
}
if per >= 100 {
return nil, errors.New("dm.thinp_percent must be greater than 0 and less than 100")
}
lvmSetupConfig.ThinpPercent = per
case "dm.thinp_metapercent":
per, err := strconv.ParseUint(strings.TrimSuffix(val, "%"), 10, 32)
if err != nil {
return nil, errors.Wrapf(err, "could not parse `dm.thinp_metapercent=%s`", val)
}
if per >= 100 {
return nil, errors.New("dm.thinp_metapercent must be greater than 0 and less than 100")
}
lvmSetupConfig.ThinpMetaPercent = per
case "dm.thinp_autoextend_percent":
per, err := strconv.ParseUint(strings.TrimSuffix(val, "%"), 10, 32)
if err != nil {
return nil, errors.Wrapf(err, "could not parse `dm.thinp_autoextend_percent=%s`", val)
}
if per > 100 {
return nil, errors.New("dm.thinp_autoextend_percent must be greater than 0 and less than 100")
}
lvmSetupConfig.AutoExtendPercent = per
case "dm.thinp_autoextend_threshold":
per, err := strconv.ParseUint(strings.TrimSuffix(val, "%"), 10, 32)
if err != nil {
return nil, errors.Wrapf(err, "could not parse `dm.thinp_autoextend_threshold=%s`", val)
}
if per > 100 {
return nil, errors.New("dm.thinp_autoextend_threshold must be greater than 0 and less than 100")
}
lvmSetupConfig.AutoExtendThreshold = per
case "dm.libdm_log_level":
level, err := strconv.ParseInt(val, 10, 32)
if err != nil {
return nil, errors.Wrapf(err, "could not parse `dm.libdm_log_level=%s`", val)
}
if level < devicemapper.LogLevelFatal || level > devicemapper.LogLevelDebug {
return nil, errors.Errorf("dm.libdm_log_level must be in range [%d,%d]", devicemapper.LogLevelFatal, devicemapper.LogLevelDebug)
}
// Register a new logging callback with the specified level.
devicemapper.LogInit(devicemapper.DefaultLogger{
Level: int(level),
})
default:
return nil, fmt.Errorf("devmapper: Unknown option %s", key)
}
}
if err := validateLVMConfig(lvmSetupConfig); err != nil {
return nil, err
}
devices.lvmSetupConfig = lvmSetupConfig
// By default, don't do blk discard hack on raw devices, its rarely useful and is expensive
if !foundBlkDiscard && (devices.dataDevice != "" || devices.thinPoolDevice != "") {
devices.doBlkDiscard = false
}
if err := devices.initDevmapper(doInit); err != nil {
return nil, err
}
return devices, nil
}