diff --git a/daemon/commit.go b/daemon/commit.go
index 3e5744c0c2..ba083598b0 100644
--- a/daemon/commit.go
+++ b/daemon/commit.go
@@ -145,7 +145,7 @@ func (daemon *Daemon) exportContainerRw(container *container.Container) (archive
}
return ioutils.NewReadCloserWrapper(archive, func() error {
archive.Close()
- return daemon.layerStore.Unmount(container.ID)
+ return container.RWLayer.Unmount()
}),
nil
}
diff --git a/daemon/container_operations_windows.go b/daemon/container_operations_windows.go
index ebbefa3eb4..2c4a24c463 100644
--- a/daemon/container_operations_windows.go
+++ b/daemon/container_operations_windows.go
@@ -98,7 +98,7 @@ func (daemon *Daemon) populateCommand(c *container.Container, env []string) erro
}
}
- m, err := daemon.layerStore.Metadata(c.ID)
+ m, err := c.RWLayer.Metadata()
if err != nil {
return derr.ErrorCodeGetLayerMetadata.WithArgs(err)
}
diff --git a/daemon/create.go b/daemon/create.go
index aa3d97896e..26b7c1c26c 100644
--- a/daemon/create.go
+++ b/daemon/create.go
@@ -7,6 +7,7 @@ import (
"github.com/docker/docker/container"
derr "github.com/docker/docker/errors"
"github.com/docker/docker/image"
+ "github.com/docker/docker/layer"
"github.com/docker/docker/pkg/idtools"
"github.com/docker/docker/pkg/stringid"
"github.com/docker/docker/volume"
@@ -95,6 +96,11 @@ func (daemon *Daemon) create(params types.ContainerCreateConfig) (*container.Con
}
}()
+ // Set RWLayer for container after mount labels have been set
+ if err := daemon.setRWLayer(container); err != nil {
+ return nil, err
+ }
+
if err := daemon.createContainerPlatformSpecificSettings(container, params.Config, params.HostConfig, img); err != nil {
return nil, err
}
@@ -126,6 +132,24 @@ func (daemon *Daemon) generateSecurityOpt(ipcMode containertypes.IpcMode, pidMod
return nil, nil
}
+func (daemon *Daemon) setRWLayer(container *container.Container) error {
+ var layerID layer.ChainID
+ if container.ImageID != "" {
+ img, err := daemon.imageStore.Get(container.ImageID)
+ if err != nil {
+ return err
+ }
+ layerID = img.RootFS.ChainID()
+ }
+ rwLayer, err := daemon.layerStore.CreateRWLayer(container.ID, layerID, container.MountLabel, daemon.setupInitLayer)
+ if err != nil {
+ return err
+ }
+ container.RWLayer = rwLayer
+
+ return nil
+}
+
// VolumeCreate creates a volume with the specified name, driver, and opts
// This is called directly from the remote API
func (daemon *Daemon) VolumeCreate(name, driverName string, opts map[string]string) (*types.Volume, error) {
diff --git a/daemon/daemon.go b/daemon/daemon.go
index 7f84de7c4f..fb8ed4600f 100644
--- a/daemon/daemon.go
+++ b/daemon/daemon.go
@@ -323,6 +323,13 @@ func (daemon *Daemon) restore() error {
continue
}
+ rwlayer, err := daemon.layerStore.GetRWLayer(container.ID)
+ if err != nil {
+ logrus.Errorf("Failed to load container mount %v: %v", id, err)
+ continue
+ }
+ container.RWLayer = rwlayer
+
// Ignore the container if it does not support the current driver being used by the graph
if (container.Driver == "" && currentDriver == "aufs") || container.Driver == currentDriver {
logrus.Debugf("Loaded container %v", container.ID)
@@ -961,19 +968,7 @@ func (daemon *Daemon) Shutdown() error {
// Mount sets container.BaseFS
// (is it not set coming in? why is it unset?)
func (daemon *Daemon) Mount(container *container.Container) error {
- var layerID layer.ChainID
- if container.ImageID != "" {
- img, err := daemon.imageStore.Get(container.ImageID)
- if err != nil {
- return err
- }
- layerID = img.RootFS.ChainID()
- }
- rwlayer, err := daemon.layerStore.Mount(container.ID, layerID, container.GetMountLabel(), daemon.setupInitLayer)
- if err != nil {
- return err
- }
- dir, err := rwlayer.Path()
+ dir, err := container.RWLayer.Mount(container.GetMountLabel())
if err != nil {
return err
}
@@ -990,13 +985,12 @@ func (daemon *Daemon) Mount(container *container.Container) error {
}
}
container.BaseFS = dir // TODO: combine these fields
- container.RWLayer = rwlayer
return nil
}
// Unmount unsets the container base filesystem
func (daemon *Daemon) Unmount(container *container.Container) {
- if err := daemon.layerStore.Unmount(container.ID); err != nil {
+ if err := container.RWLayer.Unmount(); err != nil {
logrus.Errorf("Error unmounting container %s: %s", container.ID, err)
}
}
@@ -1029,7 +1023,7 @@ func (daemon *Daemon) unsubscribeToContainerStats(c *container.Container, ch cha
}
func (daemon *Daemon) changes(container *container.Container) ([]archive.Change, error) {
- return daemon.layerStore.Changes(container.ID)
+ return container.RWLayer.Changes()
}
// TagImage creates a tag in the repository reponame, pointing to the image named
diff --git a/daemon/delete.go b/daemon/delete.go
index a282f3a9f9..e2ce1a8568 100644
--- a/daemon/delete.go
+++ b/daemon/delete.go
@@ -130,7 +130,7 @@ func (daemon *Daemon) cleanupContainer(container *container.Container, forceRemo
return derr.ErrorCodeRmFS.WithArgs(container.ID, err)
}
- metadata, err := daemon.layerStore.DeleteMount(container.ID)
+ metadata, err := daemon.layerStore.ReleaseRWLayer(container.RWLayer)
layer.LogReleaseMetadata(metadata)
if err != nil && err != layer.ErrMountDoesNotExist {
return derr.ErrorCodeRmDriverFS.WithArgs(daemon.driver, container.ID, err)
diff --git a/daemon/inspect.go b/daemon/inspect.go
index 60bebcc598..b1e4eb43a7 100644
--- a/daemon/inspect.go
+++ b/daemon/inspect.go
@@ -163,7 +163,7 @@ func (daemon *Daemon) getInspectData(container *container.Container, size bool)
contJSONBase.GraphDriver.Name = container.Driver
- graphDriverData, err := daemon.layerStore.Metadata(container.ID)
+ graphDriverData, err := container.RWLayer.Metadata()
if err != nil {
return nil, err
}
diff --git a/distribution/xfer/download_test.go b/distribution/xfer/download_test.go
index a09cd244e1..474e523694 100644
--- a/distribution/xfer/download_test.go
+++ b/distribution/xfer/download_test.go
@@ -12,7 +12,6 @@ import (
"github.com/docker/distribution/digest"
"github.com/docker/docker/image"
"github.com/docker/docker/layer"
- "github.com/docker/docker/pkg/archive"
"github.com/docker/docker/pkg/progress"
"golang.org/x/net/context"
)
@@ -115,25 +114,18 @@ func (ls *mockLayerStore) Get(chainID layer.ChainID) (layer.Layer, error) {
func (ls *mockLayerStore) Release(l layer.Layer) ([]layer.Metadata, error) {
return []layer.Metadata{}, nil
}
-
-func (ls *mockLayerStore) Mount(id string, parent layer.ChainID, label string, init layer.MountInit) (layer.RWLayer, error) {
+func (ls *mockLayerStore) CreateRWLayer(string, layer.ChainID, string, layer.MountInit) (layer.RWLayer, error) {
return nil, errors.New("not implemented")
}
-func (ls *mockLayerStore) Unmount(id string) error {
- return errors.New("not implemented")
+func (ls *mockLayerStore) GetRWLayer(string) (layer.RWLayer, error) {
+ return nil, errors.New("not implemented")
+
}
-func (ls *mockLayerStore) DeleteMount(id string) ([]layer.Metadata, error) {
+func (ls *mockLayerStore) ReleaseRWLayer(layer.RWLayer) ([]layer.Metadata, error) {
return nil, errors.New("not implemented")
-}
-func (ls *mockLayerStore) Changes(id string) ([]archive.Change, error) {
- return nil, errors.New("not implemented")
-}
-
-func (ls *mockLayerStore) Metadata(id string) (map[string]string, error) {
- return nil, errors.New("not implemented")
}
type mockDownloadDescriptor struct {
diff --git a/layer/layer.go b/layer/layer.go
index eed5937e1e..f2fa5bc6c9 100644
--- a/layer/layer.go
+++ b/layer/layer.go
@@ -31,6 +31,11 @@ var (
// attempted on a mount layer which does not exist.
ErrMountDoesNotExist = errors.New("mount does not exist")
+ // ErrMountNameConflict is used when a mount is attempted
+ // to be created but there is already a mount with the name
+ // used for creation.
+ ErrMountNameConflict = errors.New("mount already exists with name")
+
// ErrActiveMount is used when an operation on a
// mount is attempted but the layer is still
// mounted and the operation cannot be performed.
@@ -103,18 +108,33 @@ type Layer interface {
type RWLayer interface {
TarStreamer
- // Path returns the filesystem path to the writable
- // layer.
- Path() (string, error)
+ // Name of mounted layer
+ Name() string
// Parent returns the layer which the writable
// layer was created from.
Parent() Layer
+ // Mount mounts the RWLayer and returns the filesystem path
+ // the to the writable layer.
+ Mount(mountLabel string) (string, error)
+
+ // Unmount unmounts the RWLayer. This should be called
+ // for every mount. If there are multiple mount calls
+ // this operation will only decrement the internal mount counter.
+ Unmount() error
+
// Size represents the size of the writable layer
// as calculated by the total size of the files
// changed in the mutable layer.
Size() (int64, error)
+
+ // Changes returns the set of changes for the mutable layer
+ // from the base layer.
+ Changes() ([]archive.Change, error)
+
+ // Metadata returns the low level metadata for the mutable layer
+ Metadata() (map[string]string, error)
}
// Metadata holds information about a
@@ -147,11 +167,9 @@ type Store interface {
Get(ChainID) (Layer, error)
Release(Layer) ([]Metadata, error)
- Mount(id string, parent ChainID, label string, init MountInit) (RWLayer, error)
- Unmount(id string) error
- DeleteMount(id string) ([]Metadata, error)
- Changes(id string) ([]archive.Change, error)
- Metadata(id string) (map[string]string, error)
+ CreateRWLayer(id string, parent ChainID, mountLabel string, initFunc MountInit) (RWLayer, error)
+ GetRWLayer(id string) (RWLayer, error)
+ ReleaseRWLayer(RWLayer) ([]Metadata, error)
}
// MetadataTransaction represents functions for setting layer metadata
diff --git a/layer/layer_store.go b/layer/layer_store.go
index d67092f7d9..80dedfbfbc 100644
--- a/layer/layer_store.go
+++ b/layer/layer_store.go
@@ -5,7 +5,6 @@ import (
"fmt"
"io"
"io/ioutil"
- "runtime"
"sync"
"github.com/Sirupsen/logrus"
@@ -144,6 +143,7 @@ func (ls *layerStore) loadMount(mount string) error {
mountID: mountID,
initID: initID,
layerStore: ls,
+ references: map[RWLayer]*referencedRWLayer{},
}
if parent != "" {
@@ -382,15 +382,114 @@ func (ls *layerStore) Release(l Layer) ([]Metadata, error) {
return ls.releaseLayer(layer)
}
-func (ls *layerStore) mount(m *mountedLayer, mountLabel string) error {
- dir, err := ls.driver.Get(m.mountID, mountLabel)
- if err != nil {
- return err
+func (ls *layerStore) CreateRWLayer(name string, parent ChainID, mountLabel string, initFunc MountInit) (RWLayer, error) {
+ ls.mountL.Lock()
+ defer ls.mountL.Unlock()
+ m, ok := ls.mounts[name]
+ if ok {
+ return nil, ErrMountNameConflict
}
- m.path = dir
- m.activityCount++
- return nil
+ var err error
+ var pid string
+ var p *roLayer
+ if string(parent) != "" {
+ p = ls.get(parent)
+ if p == nil {
+ return nil, ErrLayerDoesNotExist
+ }
+ pid = p.cacheID
+
+ // Release parent chain if error
+ defer func() {
+ if err != nil {
+ ls.layerL.Lock()
+ ls.releaseLayer(p)
+ ls.layerL.Unlock()
+ }
+ }()
+ }
+
+ m = &mountedLayer{
+ name: name,
+ parent: p,
+ mountID: ls.mountID(name),
+ layerStore: ls,
+ references: map[RWLayer]*referencedRWLayer{},
+ }
+
+ if initFunc != nil {
+ pid, err = ls.initMount(m.mountID, pid, mountLabel, initFunc)
+ if err != nil {
+ return nil, err
+ }
+ m.initID = pid
+ }
+
+ if err = ls.driver.Create(m.mountID, pid, ""); err != nil {
+ return nil, err
+ }
+
+ if err = ls.saveMount(m); err != nil {
+ return nil, err
+ }
+
+ return m.getReference(), nil
+}
+
+func (ls *layerStore) GetRWLayer(id string) (RWLayer, error) {
+ ls.mountL.Lock()
+ defer ls.mountL.Unlock()
+ mount, ok := ls.mounts[id]
+ if !ok {
+ return nil, ErrMountDoesNotExist
+ }
+
+ return mount.getReference(), nil
+}
+
+func (ls *layerStore) ReleaseRWLayer(l RWLayer) ([]Metadata, error) {
+ ls.mountL.Lock()
+ defer ls.mountL.Unlock()
+ m, ok := ls.mounts[l.Name()]
+ if !ok {
+ return []Metadata{}, nil
+ }
+
+ if err := m.deleteReference(l); err != nil {
+ return nil, err
+ }
+
+ if m.hasReferences() {
+ return []Metadata{}, nil
+ }
+
+ if err := ls.driver.Remove(m.mountID); err != nil {
+ logrus.Errorf("Error removing mounted layer %s: %s", m.name, err)
+ return nil, err
+ }
+
+ if m.initID != "" {
+ if err := ls.driver.Remove(m.initID); err != nil {
+ logrus.Errorf("Error removing init layer %s: %s", m.name, err)
+ return nil, err
+ }
+ }
+
+ if err := ls.store.RemoveMount(m.name); err != nil {
+ logrus.Errorf("Error removing mount metadata: %s: %s", m.name, err)
+ return nil, err
+ }
+
+ delete(ls.mounts, m.Name())
+
+ ls.layerL.Lock()
+ defer ls.layerL.Unlock()
+ if m.parent != nil {
+ return ls.releaseLayer(m.parent)
+ }
+
+ return []Metadata{}, nil
}
func (ls *layerStore) saveMount(mount *mountedLayer) error {
@@ -442,145 +541,6 @@ func (ls *layerStore) initMount(graphID, parent, mountLabel string, initFunc Mou
return initID, nil
}
-func (ls *layerStore) Mount(name string, parent ChainID, mountLabel string, initFunc MountInit) (l RWLayer, err error) {
- ls.mountL.Lock()
- defer ls.mountL.Unlock()
- m, ok := ls.mounts[name]
- if ok {
- // Check if has path
- if err := ls.mount(m, mountLabel); err != nil {
- return nil, err
- }
- return m, nil
- }
-
- var pid string
- var p *roLayer
- if string(parent) != "" {
- p = ls.get(parent)
- if p == nil {
- return nil, ErrLayerDoesNotExist
- }
- pid = p.cacheID
-
- // Release parent chain if error
- defer func() {
- if err != nil {
- ls.layerL.Lock()
- ls.releaseLayer(p)
- ls.layerL.Unlock()
- }
- }()
- }
-
- mountID := name
- if runtime.GOOS != "windows" {
- // windows has issues if container ID doesn't match mount ID
- mountID = stringid.GenerateRandomID()
- }
-
- m = &mountedLayer{
- name: name,
- parent: p,
- mountID: mountID,
- layerStore: ls,
- }
-
- if initFunc != nil {
- pid, err = ls.initMount(m.mountID, pid, mountLabel, initFunc)
- if err != nil {
- return nil, err
- }
- m.initID = pid
- }
-
- if err = ls.driver.Create(m.mountID, pid, ""); err != nil {
- return nil, err
- }
-
- if err = ls.saveMount(m); err != nil {
- return nil, err
- }
-
- if err = ls.mount(m, mountLabel); err != nil {
- return nil, err
- }
-
- return m, nil
-}
-
-func (ls *layerStore) Unmount(name string) error {
- ls.mountL.Lock()
- defer ls.mountL.Unlock()
-
- m := ls.mounts[name]
- if m == nil {
- return ErrMountDoesNotExist
- }
-
- m.activityCount--
-
- if err := ls.driver.Put(m.mountID); err != nil {
- return err
- }
-
- return nil
-}
-
-func (ls *layerStore) DeleteMount(name string) ([]Metadata, error) {
- ls.mountL.Lock()
- defer ls.mountL.Unlock()
-
- m := ls.mounts[name]
- if m == nil {
- return nil, ErrMountDoesNotExist
- }
- if m.activityCount > 0 {
- return nil, ErrActiveMount
- }
-
- delete(ls.mounts, name)
-
- if err := ls.driver.Remove(m.mountID); err != nil {
- logrus.Errorf("Error removing mounted layer %s: %s", m.name, err)
- return nil, err
- }
-
- if m.initID != "" {
- if err := ls.driver.Remove(m.initID); err != nil {
- logrus.Errorf("Error removing init layer %s: %s", m.name, err)
- return nil, err
- }
- }
-
- if err := ls.store.RemoveMount(m.name); err != nil {
- logrus.Errorf("Error removing mount metadata: %s: %s", m.name, err)
- return nil, err
- }
-
- ls.layerL.Lock()
- defer ls.layerL.Unlock()
- if m.parent != nil {
- return ls.releaseLayer(m.parent)
- }
-
- return []Metadata{}, nil
-}
-
-func (ls *layerStore) Changes(name string) ([]archive.Change, error) {
- ls.mountL.Lock()
- m := ls.mounts[name]
- ls.mountL.Unlock()
- if m == nil {
- return nil, ErrMountDoesNotExist
- }
- pid := m.initID
- if pid == "" && m.parent != nil {
- pid = m.parent.cacheID
- }
- return ls.driver.Changes(m.mountID, pid)
-}
-
func (ls *layerStore) assembleTar(graphID string, metadata io.ReadCloser, size *int64) (io.ReadCloser, error) {
type diffPathDriver interface {
DiffPath(string) (string, func() error, error)
@@ -621,17 +581,6 @@ func (ls *layerStore) assembleTar(graphID string, metadata io.ReadCloser, size *
return pR, nil
}
-// Metadata returns the low level metadata from the mount with the given name
-func (ls *layerStore) Metadata(name string) (map[string]string, error) {
- ls.mountL.Lock()
- m := ls.mounts[name]
- ls.mountL.Unlock()
- if m == nil {
- return nil, ErrMountDoesNotExist
- }
- return ls.driver.GetMetadata(m.mountID)
-}
-
type naiveDiffPathDriver struct {
graphdriver.Driver
}
diff --git a/layer/layer_test.go b/layer/layer_test.go
index c3e4cf1d52..65cc15b2ae 100644
--- a/layer/layer_test.go
+++ b/layer/layer_test.go
@@ -82,12 +82,12 @@ type layerInit func(root string) error
func createLayer(ls Store, parent ChainID, layerFunc layerInit) (Layer, error) {
containerID := stringid.GenerateRandomID()
- mount, err := ls.Mount(containerID, parent, "", nil)
+ mount, err := ls.CreateRWLayer(containerID, parent, "", nil)
if err != nil {
return nil, err
}
- path, err := mount.Path()
+ path, err := mount.Mount("")
if err != nil {
return nil, err
}
@@ -107,11 +107,11 @@ func createLayer(ls Store, parent ChainID, layerFunc layerInit) (Layer, error) {
return nil, err
}
- if err := ls.Unmount(containerID); err != nil {
+ if err := mount.Unmount(); err != nil {
return nil, err
}
- if _, err := ls.DeleteMount(containerID); err != nil {
+ if _, err := ls.ReleaseRWLayer(mount); err != nil {
return nil, err
}
@@ -171,6 +171,13 @@ func getCachedLayer(l Layer) *roLayer {
return l.(*roLayer)
}
+func getMountLayer(l RWLayer) *mountedLayer {
+ if rl, ok := l.(*referencedRWLayer); ok {
+ return rl.mountedLayer
+ }
+ return l.(*mountedLayer)
+}
+
func createMetadata(layers ...Layer) []Metadata {
metadata := make([]Metadata, len(layers))
for i := range layers {
@@ -270,12 +277,12 @@ func TestMountAndRegister(t *testing.T) {
size, _ := layer.Size()
t.Logf("Layer size: %d", size)
- mount2, err := ls.Mount("new-test-mount", layer.ChainID(), "", nil)
+ mount2, err := ls.CreateRWLayer("new-test-mount", layer.ChainID(), "", nil)
if err != nil {
t.Fatal(err)
}
- path2, err := mount2.Path()
+ path2, err := mount2.Mount("")
if err != nil {
t.Fatal(err)
}
@@ -289,11 +296,11 @@ func TestMountAndRegister(t *testing.T) {
t.Fatalf("Wrong file data, expected %q, got %q", expected, string(b))
}
- if err := ls.Unmount("new-test-mount"); err != nil {
+ if err := mount2.Unmount(); err != nil {
t.Fatal(err)
}
- if _, err := ls.DeleteMount("new-test-mount"); err != nil {
+ if _, err := ls.ReleaseRWLayer(mount2); err != nil {
t.Fatal(err)
}
}
@@ -370,12 +377,12 @@ func TestStoreRestore(t *testing.T) {
t.Fatal(err)
}
- m, err := ls.Mount("some-mount_name", layer3.ChainID(), "", nil)
+ m, err := ls.CreateRWLayer("some-mount_name", layer3.ChainID(), "", nil)
if err != nil {
t.Fatal(err)
}
- path, err := m.Path()
+ path, err := m.Mount("")
if err != nil {
t.Fatal(err)
}
@@ -383,11 +390,14 @@ func TestStoreRestore(t *testing.T) {
if err := ioutil.WriteFile(filepath.Join(path, "testfile.txt"), []byte("nothing here"), 0644); err != nil {
t.Fatal(err)
}
+ assertActivityCount(t, m, 1)
- if err := ls.Unmount("some-mount_name"); err != nil {
+ if err := m.Unmount(); err != nil {
t.Fatal(err)
}
+ assertActivityCount(t, m, 0)
+
ls2, err := NewStore(ls.(*layerStore).store, ls.(*layerStore).driver)
if err != nil {
t.Fatal(err)
@@ -400,18 +410,39 @@ func TestStoreRestore(t *testing.T) {
assertLayerEqual(t, layer3b, layer3)
- // Mount again with same name, should already be loaded
- m2, err := ls2.Mount("some-mount_name", layer3b.ChainID(), "", nil)
+ // Create again with same name, should return error
+ if _, err := ls2.CreateRWLayer("some-mount_name", layer3b.ChainID(), "", nil); err == nil {
+ t.Fatal("Expected error creating mount with same name")
+ } else if err != ErrMountNameConflict {
+ t.Fatal(err)
+ }
+
+ m2, err := ls2.GetRWLayer("some-mount_name")
if err != nil {
t.Fatal(err)
}
- path2, err := m2.Path()
- if err != nil {
+ if mountPath, err := m2.Mount(""); err != nil {
+ t.Fatal(err)
+ } else if path != mountPath {
+ t.Fatalf("Unexpected path %s, expected %s", mountPath, path)
+ }
+
+ assertActivityCount(t, m2, 1)
+
+ if mountPath, err := m2.Mount(""); err != nil {
+ t.Fatal(err)
+ } else if path != mountPath {
+ t.Fatalf("Unexpected path %s, expected %s", mountPath, path)
+ }
+ assertActivityCount(t, m2, 2)
+ if err := m2.Unmount(); err != nil {
t.Fatal(err)
}
- b, err := ioutil.ReadFile(filepath.Join(path2, "testfile.txt"))
+ assertActivityCount(t, m2, 1)
+
+ b, err := ioutil.ReadFile(filepath.Join(path, "testfile.txt"))
if err != nil {
t.Fatal(err)
}
@@ -419,11 +450,19 @@ func TestStoreRestore(t *testing.T) {
t.Fatalf("Unexpected content %q, expected %q", string(b), expected)
}
- if err := ls2.Unmount("some-mount_name"); err != nil {
+ if err := m2.Unmount(); err != nil {
t.Fatal(err)
}
- if metadata, err := ls2.DeleteMount("some-mount_name"); err != nil {
+ assertActivityCount(t, m2, 0)
+
+ if metadata, err := ls2.ReleaseRWLayer(m2); err != nil {
+ t.Fatal(err)
+ } else if len(metadata) != 0 {
+ t.Fatalf("Unexpectedly deleted layers: %#v", metadata)
+ }
+
+ if metadata, err := ls2.ReleaseRWLayer(m2); err != nil {
t.Fatal(err)
} else if len(metadata) != 0 {
t.Fatalf("Unexpectedly deleted layers: %#v", metadata)
@@ -627,6 +666,13 @@ func assertReferences(t *testing.T, references ...Layer) {
}
}
+func assertActivityCount(t *testing.T, l RWLayer, expected int) {
+ rl := l.(*referencedRWLayer)
+ if rl.activityCount != expected {
+ t.Fatalf("Unexpected activity count %d, expected %d", rl.activityCount, expected)
+ }
+}
+
func TestRegisterExistingLayer(t *testing.T) {
ls, cleanup := newTestStore(t)
defer cleanup()
diff --git a/layer/layer_unix.go b/layer/layer_unix.go
new file mode 100644
index 0000000000..524b97e8d1
--- /dev/null
+++ b/layer/layer_unix.go
@@ -0,0 +1,9 @@
+// +build linux freebsd darwin
+
+package layer
+
+import "github.com/docker/docker/pkg/stringid"
+
+func (ls *layerStore) mountID(name string) string {
+ return stringid.GenerateRandomID()
+}
diff --git a/layer/layer_windows.go b/layer/layer_windows.go
index 369281448a..c40144d860 100644
--- a/layer/layer_windows.go
+++ b/layer/layer_windows.go
@@ -89,3 +89,8 @@ func (ls *layerStore) RegisterDiffID(graphID string, size int64) (Layer, error)
return layer.getReference(), nil
}
+
+func (ls *layerStore) mountID(name string) string {
+ // windows has issues if container ID doesn't match mount ID
+ return name
+}
diff --git a/layer/migration.go b/layer/migration.go
index bc448a59a5..50dbcaec80 100644
--- a/layer/migration.go
+++ b/layer/migration.go
@@ -14,30 +14,33 @@ import (
"github.com/vbatts/tar-split/tar/storage"
)
-func (ls *layerStore) MountByGraphID(name string, graphID string, parent ChainID) (l RWLayer, err error) {
+// CreateRWLayerByGraphID creates a RWLayer in the layer store using
+// the provided name with the given graphID. To get the RWLayer
+// after migration the layer may be retrieved by the given name.
+func (ls *layerStore) CreateRWLayerByGraphID(name string, graphID string, parent ChainID) (err error) {
ls.mountL.Lock()
defer ls.mountL.Unlock()
m, ok := ls.mounts[name]
if ok {
if m.parent.chainID != parent {
- return nil, errors.New("name conflict, mismatched parent")
+ return errors.New("name conflict, mismatched parent")
}
if m.mountID != graphID {
- return nil, errors.New("mount already exists")
+ return errors.New("mount already exists")
}
- return m, nil
+ return nil
}
if !ls.driver.Exists(graphID) {
- return nil, errors.New("graph ID does not exist")
+ return errors.New("graph ID does not exist")
}
var p *roLayer
if string(parent) != "" {
p = ls.get(parent)
if p == nil {
- return nil, ErrLayerDoesNotExist
+ return ErrLayerDoesNotExist
}
// Release parent chain if error
@@ -57,6 +60,7 @@ func (ls *layerStore) MountByGraphID(name string, graphID string, parent ChainID
parent: p,
mountID: graphID,
layerStore: ls,
+ references: map[RWLayer]*referencedRWLayer{},
}
// Check for existing init layer
@@ -66,15 +70,10 @@ func (ls *layerStore) MountByGraphID(name string, graphID string, parent ChainID
}
if err = ls.saveMount(m); err != nil {
- return nil, err
+ return err
}
- // TODO: provide a mount label
- if err = ls.mount(m, ""); err != nil {
- return nil, err
- }
-
- return m, nil
+ return nil
}
func (ls *layerStore) migrateLayer(tx MetadataTransaction, tarDataFile string, layer *roLayer) error {
diff --git a/layer/migration_test.go b/layer/migration_test.go
index 11614ffde0..509e0c4eb5 100644
--- a/layer/migration_test.go
+++ b/layer/migration_test.go
@@ -303,12 +303,20 @@ func TestMountMigration(t *testing.T) {
t.Fatal(err)
}
- rwLayer1, err := ls.(*layerStore).MountByGraphID("migration-mount", containerID, layer1.ChainID())
+ if err := ls.(*layerStore).CreateRWLayerByGraphID("migration-mount", containerID, layer1.ChainID()); err != nil {
+ t.Fatal(err)
+ }
+
+ rwLayer1, err := ls.GetRWLayer("migration-mount")
if err != nil {
t.Fatal(err)
}
- changes, err := ls.Changes("migration-mount")
+ if _, err := rwLayer1.Mount(""); err != nil {
+ t.Fatal(err)
+ }
+
+ changes, err := rwLayer1.Changes()
if err != nil {
t.Fatal(err)
}
@@ -341,39 +349,63 @@ func TestMountMigration(t *testing.T) {
Kind: archive.ChangeAdd,
})
- if expectedCount := 1; rwLayer1.(*mountedLayer).activityCount != expectedCount {
- t.Fatalf("Wrong activity count %d, expected %d", rwLayer1.(*mountedLayer).activityCount, expectedCount)
+ assertActivityCount(t, rwLayer1, 1)
+
+ if _, err := ls.CreateRWLayer("migration-mount", layer1.ChainID(), "", nil); err == nil {
+ t.Fatal("Expected error creating mount with same name")
+ } else if err != ErrMountNameConflict {
+ t.Fatal(err)
}
- rwLayer2, err := ls.Mount("migration-mount", layer1.ChainID(), "", nil)
+ rwLayer2, err := ls.GetRWLayer("migration-mount")
if err != nil {
t.Fatal(err)
}
- if rwLayer1 != rwLayer2 {
- t.Fatalf("Wrong rwlayer %v, expected %v", rwLayer2, rwLayer1)
+ if getMountLayer(rwLayer1) != getMountLayer(rwLayer2) {
+ t.Fatal("Expected same layer from get with same name as from migrate")
}
- if expectedCount := 2; rwLayer2.(*mountedLayer).activityCount != expectedCount {
- t.Fatalf("Wrong activity count %d, expected %d", rwLayer2.(*mountedLayer).activityCount, expectedCount)
+ if _, err := rwLayer2.Mount(""); err != nil {
+ t.Fatal(err)
}
+ assertActivityCount(t, rwLayer2, 1)
+ assertActivityCount(t, rwLayer1, 1)
+
+ if _, err := rwLayer2.Mount(""); err != nil {
+ t.Fatal(err)
+ }
+
+ assertActivityCount(t, rwLayer2, 2)
+ assertActivityCount(t, rwLayer1, 1)
+
if metadata, err := ls.Release(layer1); err != nil {
t.Fatal(err)
} else if len(metadata) > 0 {
t.Fatalf("Expected no layers to be deleted, deleted %#v", metadata)
}
- if err := ls.Unmount("migration-mount"); err != nil {
+ if err := rwLayer1.Unmount(); err != nil {
t.Fatal(err)
}
- if _, err := ls.DeleteMount("migration-mount"); err == nil {
+ assertActivityCount(t, rwLayer2, 2)
+ assertActivityCount(t, rwLayer1, 0)
+
+ if _, err := ls.ReleaseRWLayer(rwLayer1); err != nil {
+ t.Fatal(err)
+ }
+
+ if err := rwLayer2.Unmount(); err != nil {
+ t.Fatal(err)
+ }
+ if _, err := ls.ReleaseRWLayer(rwLayer2); err == nil {
t.Fatal("Expected error deleting active mount")
}
- if err := ls.Unmount("migration-mount"); err != nil {
+ if err := rwLayer2.Unmount(); err != nil {
t.Fatal(err)
}
- metadata, err := ls.DeleteMount("migration-mount")
+ metadata, err := ls.ReleaseRWLayer(rwLayer2)
if err != nil {
t.Fatal(err)
}
diff --git a/layer/mount_test.go b/layer/mount_test.go
index 195f81193d..6889912e6d 100644
--- a/layer/mount_test.go
+++ b/layer/mount_test.go
@@ -27,12 +27,12 @@ func TestMountInit(t *testing.T) {
return initfile.ApplyFile(root)
}
- m, err := ls.Mount("fun-mount", layer.ChainID(), "", mountInit)
+ m, err := ls.CreateRWLayer("fun-mount", layer.ChainID(), "", mountInit)
if err != nil {
t.Fatal(err)
}
- path, err := m.Path()
+ path, err := m.Mount("")
if err != nil {
t.Fatal(err)
}
@@ -80,12 +80,12 @@ func TestMountSize(t *testing.T) {
return newTestFile("file-init", contentInit, 0777).ApplyFile(root)
}
- m, err := ls.Mount("mount-size", layer.ChainID(), "", mountInit)
+ m, err := ls.CreateRWLayer("mount-size", layer.ChainID(), "", mountInit)
if err != nil {
t.Fatal(err)
}
- path, err := m.Path()
+ path, err := m.Mount("")
if err != nil {
t.Fatal(err)
}
@@ -125,12 +125,12 @@ func TestMountChanges(t *testing.T) {
return initfile.ApplyFile(root)
}
- m, err := ls.Mount("mount-changes", layer.ChainID(), "", mountInit)
+ m, err := ls.CreateRWLayer("mount-changes", layer.ChainID(), "", mountInit)
if err != nil {
t.Fatal(err)
}
- path, err := m.Path()
+ path, err := m.Mount("")
if err != nil {
t.Fatal(err)
}
@@ -155,7 +155,7 @@ func TestMountChanges(t *testing.T) {
t.Fatal(err)
}
- changes, err := ls.Changes("mount-changes")
+ changes, err := m.Changes()
if err != nil {
t.Fatal(err)
}
diff --git a/layer/mounted_layer.go b/layer/mounted_layer.go
index 35f43609c6..b3d6568833 100644
--- a/layer/mounted_layer.go
+++ b/layer/mounted_layer.go
@@ -1,15 +1,20 @@
package layer
-import "io"
+import (
+ "io"
+ "sync"
+
+ "github.com/docker/docker/pkg/archive"
+)
type mountedLayer struct {
- name string
- mountID string
- initID string
- parent *roLayer
- path string
- layerStore *layerStore
- activityCount int
+ name string
+ mountID string
+ initID string
+ parent *roLayer
+ layerStore *layerStore
+
+ references map[RWLayer]*referencedRWLayer
}
func (ml *mountedLayer) cacheParent() string {
@@ -30,11 +35,8 @@ func (ml *mountedLayer) TarStream() (io.ReadCloser, error) {
return archiver, nil
}
-func (ml *mountedLayer) Path() (string, error) {
- if ml.path == "" {
- return "", ErrNotMounted
- }
- return ml.path, nil
+func (ml *mountedLayer) Name() string {
+ return ml.name
}
func (ml *mountedLayer) Parent() Layer {
@@ -47,6 +49,96 @@ func (ml *mountedLayer) Parent() Layer {
return nil
}
+func (ml *mountedLayer) Mount(mountLabel string) (string, error) {
+ return ml.layerStore.driver.Get(ml.mountID, mountLabel)
+}
+
+func (ml *mountedLayer) Unmount() error {
+ return ml.layerStore.driver.Put(ml.mountID)
+}
+
func (ml *mountedLayer) Size() (int64, error) {
return ml.layerStore.driver.DiffSize(ml.mountID, ml.cacheParent())
}
+
+func (ml *mountedLayer) Changes() ([]archive.Change, error) {
+ return ml.layerStore.driver.Changes(ml.mountID, ml.cacheParent())
+}
+
+func (ml *mountedLayer) Metadata() (map[string]string, error) {
+ return ml.layerStore.driver.GetMetadata(ml.mountID)
+}
+
+func (ml *mountedLayer) getReference() RWLayer {
+ ref := &referencedRWLayer{
+ mountedLayer: ml,
+ }
+ ml.references[ref] = ref
+
+ return ref
+}
+
+func (ml *mountedLayer) hasReferences() bool {
+ return len(ml.references) > 0
+}
+
+func (ml *mountedLayer) deleteReference(ref RWLayer) error {
+ rl, ok := ml.references[ref]
+ if !ok {
+ return ErrLayerNotRetained
+ }
+
+ if err := rl.release(); err != nil {
+ return err
+ }
+ delete(ml.references, ref)
+
+ return nil
+}
+
+type referencedRWLayer struct {
+ *mountedLayer
+
+ activityL sync.Mutex
+ activityCount int
+}
+
+func (rl *referencedRWLayer) release() error {
+ rl.activityL.Lock()
+ defer rl.activityL.Unlock()
+
+ if rl.activityCount > 0 {
+ return ErrActiveMount
+ }
+
+ rl.activityCount = -1
+
+ return nil
+}
+
+func (rl *referencedRWLayer) Mount(mountLabel string) (string, error) {
+ rl.activityL.Lock()
+ defer rl.activityL.Unlock()
+
+ if rl.activityCount == -1 {
+ return "", ErrLayerNotRetained
+ }
+
+ rl.activityCount++
+ return rl.mountedLayer.Mount(mountLabel)
+}
+
+func (rl *referencedRWLayer) Unmount() error {
+ rl.activityL.Lock()
+ defer rl.activityL.Unlock()
+
+ if rl.activityCount == 0 {
+ return ErrNotMounted
+ }
+ if rl.activityCount == -1 {
+ return ErrLayerNotRetained
+ }
+ rl.activityCount--
+
+ return rl.mountedLayer.Unmount()
+}
diff --git a/migrate/v1/migratev1.go b/migrate/v1/migratev1.go
index a9110bca9c..c92c0f2107 100644
--- a/migrate/v1/migratev1.go
+++ b/migrate/v1/migratev1.go
@@ -24,8 +24,7 @@ type graphIDRegistrar interface {
}
type graphIDMounter interface {
- MountByGraphID(string, string, layer.ChainID) (layer.RWLayer, error)
- Unmount(string) error
+ CreateRWLayerByGraphID(string, string, layer.ChainID) error
}
const (
@@ -172,13 +171,7 @@ func migrateContainers(root string, ls graphIDMounter, is image.Store, imageMapp
return err
}
- _, err = ls.MountByGraphID(id, id, img.RootFS.ChainID())
- if err != nil {
- return err
- }
-
- err = ls.Unmount(id)
- if err != nil {
+ if err := ls.CreateRWLayerByGraphID(id, id, img.RootFS.ChainID()); err != nil {
return err
}
diff --git a/migrate/v1/migratev1_test.go b/migrate/v1/migratev1_test.go
index 067d04c382..5ee8206fdf 100644
--- a/migrate/v1/migratev1_test.go
+++ b/migrate/v1/migratev1_test.go
@@ -338,10 +338,9 @@ type mockMounter struct {
count int
}
-func (r *mockMounter) MountByGraphID(name string, graphID string, parent layer.ChainID) (layer.RWLayer, error) {
+func (r *mockMounter) CreateRWLayerByGraphID(name string, graphID string, parent layer.ChainID) error {
r.mounts = append(r.mounts, mountInfo{name, graphID, string(parent)})
- r.count++
- return nil, nil
+ return nil
}
func (r *mockMounter) Unmount(string) error {
r.count--