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3609b051b8
If this is at the root directory for the daemon you could unmount
somones filesystem when you stop docker and this is actually only needed
for the palces that the graph drivers mount the container's root
filesystems.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@crosbymichael.com> (github: crosbymichael)
126 lines
2.8 KiB
Go
126 lines
2.8 KiB
Go
package graphdriver
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import (
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"errors"
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"fmt"
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"os"
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"path"
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"github.com/dotcloud/docker/archive"
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"github.com/dotcloud/docker/pkg/mount"
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)
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type FsMagic uint64
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const (
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FsMagicBtrfs = FsMagic(0x9123683E)
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FsMagicAufs = FsMagic(0x61756673)
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)
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type InitFunc func(root string, options []string) (Driver, error)
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type Driver interface {
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String() string
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Create(id, parent string) error
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Remove(id string) error
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Get(id, mountLabel string) (dir string, err error)
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Put(id string)
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Exists(id string) bool
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Status() [][2]string
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Cleanup() error
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}
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type Differ interface {
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Diff(id string) (archive.Archive, error)
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Changes(id string) ([]archive.Change, error)
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ApplyDiff(id string, diff archive.ArchiveReader) error
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DiffSize(id string) (bytes int64, err error)
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}
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var (
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DefaultDriver string
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// All registred drivers
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drivers map[string]InitFunc
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// Slice of drivers that should be used in an order
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priority = []string{
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"aufs",
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"btrfs",
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"devicemapper",
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"vfs",
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}
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ErrNotSupported = errors.New("driver not supported")
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ErrPrerequisites = errors.New("prerequisites for driver not satisfied (wrong filesystem?)")
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ErrIncompatibleFS = fmt.Errorf("backing file system is unsupported for this graph driver")
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)
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func init() {
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drivers = make(map[string]InitFunc)
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}
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func Register(name string, initFunc InitFunc) error {
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if _, exists := drivers[name]; exists {
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return fmt.Errorf("Name already registered %s", name)
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}
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drivers[name] = initFunc
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return nil
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}
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func GetDriver(name, home string, options []string) (Driver, error) {
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if initFunc, exists := drivers[name]; exists {
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return initFunc(path.Join(home, name), options)
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}
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return nil, ErrNotSupported
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}
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func New(root string, options []string) (driver Driver, err error) {
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for _, name := range []string{os.Getenv("DOCKER_DRIVER"), DefaultDriver} {
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if name != "" {
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return GetDriver(name, root, options)
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}
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}
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// Check for priority drivers first
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for _, name := range priority {
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driver, err = GetDriver(name, root, options)
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if err != nil {
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if err == ErrNotSupported || err == ErrPrerequisites || err == ErrIncompatibleFS {
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continue
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}
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return nil, err
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}
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return driver, nil
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}
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// Check all registered drivers if no priority driver is found
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for _, initFunc := range drivers {
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if driver, err = initFunc(root, options); err != nil {
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if err == ErrNotSupported || err == ErrPrerequisites || err == ErrIncompatibleFS {
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continue
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}
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return nil, err
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}
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return driver, nil
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}
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return nil, fmt.Errorf("No supported storage backend found")
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}
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func MakePrivate(mountPoint string) error {
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mounted, err := mount.Mounted(mountPoint)
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if err != nil {
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return err
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}
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if !mounted {
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if err := mount.Mount(mountPoint, mountPoint, "none", "bind,rw"); err != nil {
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return err
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}
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}
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return mount.ForceMount("", mountPoint, "none", "private")
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}
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