mirror of
https://github.com/genuinetools/reg.git
synced 2024-09-12 06:11:03 -04:00
258 lines
7.8 KiB
Go
258 lines
7.8 KiB
Go
// +build linux
|
|
|
|
package devmapper // import "github.com/docker/docker/daemon/graphdriver/devmapper"
|
|
|
|
import (
|
|
"fmt"
|
|
"io/ioutil"
|
|
"os"
|
|
"path"
|
|
"strconv"
|
|
|
|
"github.com/docker/docker/daemon/graphdriver"
|
|
"github.com/docker/docker/pkg/containerfs"
|
|
"github.com/docker/docker/pkg/devicemapper"
|
|
"github.com/docker/docker/pkg/idtools"
|
|
"github.com/docker/docker/pkg/locker"
|
|
"github.com/docker/docker/pkg/mount"
|
|
units "github.com/docker/go-units"
|
|
"github.com/pkg/errors"
|
|
"github.com/sirupsen/logrus"
|
|
"golang.org/x/sys/unix"
|
|
)
|
|
|
|
func init() {
|
|
graphdriver.Register("devicemapper", Init)
|
|
}
|
|
|
|
// Driver contains the device set mounted and the home directory
|
|
type Driver struct {
|
|
*DeviceSet
|
|
home string
|
|
uidMaps []idtools.IDMap
|
|
gidMaps []idtools.IDMap
|
|
ctr *graphdriver.RefCounter
|
|
locker *locker.Locker
|
|
}
|
|
|
|
// Init creates a driver with the given home and the set of options.
|
|
func Init(home string, options []string, uidMaps, gidMaps []idtools.IDMap) (graphdriver.Driver, error) {
|
|
deviceSet, err := NewDeviceSet(home, true, options, uidMaps, gidMaps)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
d := &Driver{
|
|
DeviceSet: deviceSet,
|
|
home: home,
|
|
uidMaps: uidMaps,
|
|
gidMaps: gidMaps,
|
|
ctr: graphdriver.NewRefCounter(graphdriver.NewDefaultChecker()),
|
|
locker: locker.New(),
|
|
}
|
|
|
|
return graphdriver.NewNaiveDiffDriver(d, uidMaps, gidMaps), nil
|
|
}
|
|
|
|
func (d *Driver) String() string {
|
|
return "devicemapper"
|
|
}
|
|
|
|
// Status returns the status about the driver in a printable format.
|
|
// Information returned contains Pool Name, Data File, Metadata file, disk usage by
|
|
// the data and metadata, etc.
|
|
func (d *Driver) Status() [][2]string {
|
|
s := d.DeviceSet.Status()
|
|
|
|
status := [][2]string{
|
|
{"Pool Name", s.PoolName},
|
|
{"Pool Blocksize", units.HumanSize(float64(s.SectorSize))},
|
|
{"Base Device Size", units.HumanSize(float64(s.BaseDeviceSize))},
|
|
{"Backing Filesystem", s.BaseDeviceFS},
|
|
{"Udev Sync Supported", fmt.Sprintf("%v", s.UdevSyncSupported)},
|
|
}
|
|
|
|
if len(s.DataFile) > 0 {
|
|
status = append(status, [2]string{"Data file", s.DataFile})
|
|
}
|
|
if len(s.MetadataFile) > 0 {
|
|
status = append(status, [2]string{"Metadata file", s.MetadataFile})
|
|
}
|
|
if len(s.DataLoopback) > 0 {
|
|
status = append(status, [2]string{"Data loop file", s.DataLoopback})
|
|
}
|
|
if len(s.MetadataLoopback) > 0 {
|
|
status = append(status, [2]string{"Metadata loop file", s.MetadataLoopback})
|
|
}
|
|
|
|
status = append(status, [][2]string{
|
|
{"Data Space Used", units.HumanSize(float64(s.Data.Used))},
|
|
{"Data Space Total", units.HumanSize(float64(s.Data.Total))},
|
|
{"Data Space Available", units.HumanSize(float64(s.Data.Available))},
|
|
{"Metadata Space Used", units.HumanSize(float64(s.Metadata.Used))},
|
|
{"Metadata Space Total", units.HumanSize(float64(s.Metadata.Total))},
|
|
{"Metadata Space Available", units.HumanSize(float64(s.Metadata.Available))},
|
|
{"Thin Pool Minimum Free Space", units.HumanSize(float64(s.MinFreeSpace))},
|
|
{"Deferred Removal Enabled", fmt.Sprintf("%v", s.DeferredRemoveEnabled)},
|
|
{"Deferred Deletion Enabled", fmt.Sprintf("%v", s.DeferredDeleteEnabled)},
|
|
{"Deferred Deleted Device Count", fmt.Sprintf("%v", s.DeferredDeletedDeviceCount)},
|
|
}...)
|
|
|
|
if vStr, err := devicemapper.GetLibraryVersion(); err == nil {
|
|
status = append(status, [2]string{"Library Version", vStr})
|
|
}
|
|
return status
|
|
}
|
|
|
|
// GetMetadata returns a map of information about the device.
|
|
func (d *Driver) GetMetadata(id string) (map[string]string, error) {
|
|
m, err := d.DeviceSet.exportDeviceMetadata(id)
|
|
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
metadata := make(map[string]string)
|
|
metadata["DeviceId"] = strconv.Itoa(m.deviceID)
|
|
metadata["DeviceSize"] = strconv.FormatUint(m.deviceSize, 10)
|
|
metadata["DeviceName"] = m.deviceName
|
|
return metadata, nil
|
|
}
|
|
|
|
// Cleanup unmounts a device.
|
|
func (d *Driver) Cleanup() error {
|
|
err := d.DeviceSet.Shutdown(d.home)
|
|
umountErr := mount.RecursiveUnmount(d.home)
|
|
|
|
// in case we have two errors, prefer the one from Shutdown()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
|
|
if umountErr != nil {
|
|
return errors.Wrapf(umountErr, "error unmounting %s", d.home)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// CreateReadWrite creates a layer that is writable for use as a container
|
|
// file system.
|
|
func (d *Driver) CreateReadWrite(id, parent string, opts *graphdriver.CreateOpts) error {
|
|
return d.Create(id, parent, opts)
|
|
}
|
|
|
|
// Create adds a device with a given id and the parent.
|
|
func (d *Driver) Create(id, parent string, opts *graphdriver.CreateOpts) error {
|
|
var storageOpt map[string]string
|
|
if opts != nil {
|
|
storageOpt = opts.StorageOpt
|
|
}
|
|
return d.DeviceSet.AddDevice(id, parent, storageOpt)
|
|
}
|
|
|
|
// Remove removes a device with a given id, unmounts the filesystem, and removes the mount point.
|
|
func (d *Driver) Remove(id string) error {
|
|
d.locker.Lock(id)
|
|
defer d.locker.Unlock(id)
|
|
if !d.DeviceSet.HasDevice(id) {
|
|
// Consider removing a non-existing device a no-op
|
|
// This is useful to be able to progress on container removal
|
|
// if the underlying device has gone away due to earlier errors
|
|
return nil
|
|
}
|
|
|
|
// This assumes the device has been properly Get/Put:ed and thus is unmounted
|
|
if err := d.DeviceSet.DeleteDevice(id, false); err != nil {
|
|
return fmt.Errorf("failed to remove device %s: %v", id, err)
|
|
}
|
|
|
|
// Most probably the mount point is already removed on Put()
|
|
// (see DeviceSet.UnmountDevice()), but just in case it was not
|
|
// let's try to remove it here as well, ignoring errors as
|
|
// an older kernel can return EBUSY if e.g. the mount was leaked
|
|
// to other mount namespaces. A failure to remove the container's
|
|
// mount point is not important and should not be treated
|
|
// as a failure to remove the container.
|
|
mp := path.Join(d.home, "mnt", id)
|
|
err := unix.Rmdir(mp)
|
|
if err != nil && !os.IsNotExist(err) {
|
|
logrus.WithField("storage-driver", "devicemapper").Warnf("unable to remove mount point %q: %s", mp, err)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// Get mounts a device with given id into the root filesystem
|
|
func (d *Driver) Get(id, mountLabel string) (containerfs.ContainerFS, error) {
|
|
d.locker.Lock(id)
|
|
defer d.locker.Unlock(id)
|
|
mp := path.Join(d.home, "mnt", id)
|
|
rootFs := path.Join(mp, "rootfs")
|
|
if count := d.ctr.Increment(mp); count > 1 {
|
|
return containerfs.NewLocalContainerFS(rootFs), nil
|
|
}
|
|
|
|
uid, gid, err := idtools.GetRootUIDGID(d.uidMaps, d.gidMaps)
|
|
if err != nil {
|
|
d.ctr.Decrement(mp)
|
|
return nil, err
|
|
}
|
|
|
|
// Create the target directories if they don't exist
|
|
if err := idtools.MkdirAllAndChown(path.Join(d.home, "mnt"), 0755, idtools.IDPair{UID: uid, GID: gid}); err != nil {
|
|
d.ctr.Decrement(mp)
|
|
return nil, err
|
|
}
|
|
if err := idtools.MkdirAndChown(mp, 0755, idtools.IDPair{UID: uid, GID: gid}); err != nil && !os.IsExist(err) {
|
|
d.ctr.Decrement(mp)
|
|
return nil, err
|
|
}
|
|
|
|
// Mount the device
|
|
if err := d.DeviceSet.MountDevice(id, mp, mountLabel); err != nil {
|
|
d.ctr.Decrement(mp)
|
|
return nil, err
|
|
}
|
|
|
|
if err := idtools.MkdirAllAndChown(rootFs, 0755, idtools.IDPair{UID: uid, GID: gid}); err != nil {
|
|
d.ctr.Decrement(mp)
|
|
d.DeviceSet.UnmountDevice(id, mp)
|
|
return nil, err
|
|
}
|
|
|
|
idFile := path.Join(mp, "id")
|
|
if _, err := os.Stat(idFile); err != nil && os.IsNotExist(err) {
|
|
// Create an "id" file with the container/image id in it to help reconstruct this in case
|
|
// of later problems
|
|
if err := ioutil.WriteFile(idFile, []byte(id), 0600); err != nil {
|
|
d.ctr.Decrement(mp)
|
|
d.DeviceSet.UnmountDevice(id, mp)
|
|
return nil, err
|
|
}
|
|
}
|
|
|
|
return containerfs.NewLocalContainerFS(rootFs), nil
|
|
}
|
|
|
|
// Put unmounts a device and removes it.
|
|
func (d *Driver) Put(id string) error {
|
|
d.locker.Lock(id)
|
|
defer d.locker.Unlock(id)
|
|
mp := path.Join(d.home, "mnt", id)
|
|
if count := d.ctr.Decrement(mp); count > 0 {
|
|
return nil
|
|
}
|
|
|
|
err := d.DeviceSet.UnmountDevice(id, mp)
|
|
if err != nil {
|
|
logrus.Errorf("devmapper: Error unmounting device %s: %v", id, err)
|
|
}
|
|
|
|
return err
|
|
}
|
|
|
|
// Exists checks to see if the device exists.
|
|
func (d *Driver) Exists(id string) bool {
|
|
return d.DeviceSet.HasDevice(id)
|
|
}
|