1. docker
  2. Commit b890c20555596911d203befaf0e30efece6371d7
Browse code

pkg/archive: use mount pkg

It makes sense to use mount package here because
- it no longer requires /proc to be mounted
- it provides verbose errors so the caller doesn't have to

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

Kir Kolyshkin authored on 2020/03/10 04:14:02
Showing 3 changed files
pkg/archive/archive_linux.go
History View file @ b890c20
... ... 
@@ -10,6 +10,7 @@ import (
10 10 
 	"syscall"
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 	"github.com/containerd/continuity/fs"
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+	"github.com/docker/docker/pkg/mount"
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 	"github.com/docker/docker/pkg/system"
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 	"github.com/pkg/errors"
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 	"golang.org/x/sys/unix"
... ... 
@@ -152,9 +153,8 @@ func mknodChar0Overlay(cleansedOriginalPath string) error {
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 		return errors.Wrapf(err, "failed to create a dummy lower file %s", lowerDummy)
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 	}
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 	mOpts := fmt.Sprintf("lowerdir=%s,upperdir=%s,workdir=%s", lower, upper, work)
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-	// docker/pkg/mount.Mount() requires procfs to be mounted. So we use syscall.Mount() directly instead.
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-	if err := syscall.Mount("overlay", merged, "overlay", uintptr(0), mOpts); err != nil {
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-		return errors.Wrapf(err, "failed to mount overlay (%s) on %s", mOpts, merged)
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+	if err := mount.Mount("overlay", merged, "overlay", mOpts); err != nil {
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+		return err
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 	}
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 	mergedDummy := filepath.Join(merged, dummyBase)
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 	if err := os.Remove(mergedDummy); err != nil {
... ... 
@@ -237,9 +237,8 @@ func createDirWithOverlayOpaque(tmp string) (string, error) {
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 		return "", errors.Wrapf(err, "failed to create a dummy lower directory %s", lowerDummy)
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 	}
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 	mOpts := fmt.Sprintf("lowerdir=%s,upperdir=%s,workdir=%s", lower, upper, work)
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-	// docker/pkg/mount.Mount() requires procfs to be mounted. So we use syscall.Mount() directly instead.
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-	if err := syscall.Mount("overlay", merged, "overlay", uintptr(0), mOpts); err != nil {
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-		return "", errors.Wrapf(err, "failed to mount overlay (%s) on %s", mOpts, merged)
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+	if err := mount.Mount("overlay", merged, "overlay", mOpts); err != nil {
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+		return "", err
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 	}
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 	mergedDummy := filepath.Join(merged, dummyBase)
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 	if err := os.Remove(mergedDummy); err != nil {
pkg/archive/archive_linux_test.go
History View file @ b890c20
... ... 
@@ -9,6 +9,7 @@ import (
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 	"syscall"
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 	"testing"
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+	"github.com/docker/docker/pkg/mount"
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 	"github.com/docker/docker/pkg/reexec"
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 	"github.com/docker/docker/pkg/system"
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 	rsystem "github.com/opencontainers/runc/libcontainer/system"
... ... 
@@ -204,11 +205,11 @@ func supportsOverlay(dir string) error {
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 		}
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 	}
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 	mOpts := fmt.Sprintf("lowerdir=%s,upperdir=%s,workdir=%s", lower, upper, work)
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-	if err := syscall.Mount("overlay", merged, "overlay", uintptr(0), mOpts); err != nil {
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-		return errors.Wrapf(err, "failed to mount overlay (%s) on %s", mOpts, merged)
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+	if err := mount.Mount("overlay", merged, "overlay", mOpts); err != nil {
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+		return err
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 	}
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-	if err := syscall.Unmount(merged, 0); err != nil {
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-		return errors.Wrapf(err, "failed to unmount %s", merged)
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+	if err := mount.Unmount(merged); err != nil {
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+		return err
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 	}
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 	return nil
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 }
pkg/mount/mount.go
History View file @ b890c20
... ... 
@@ -105,7 +105,7 @@ func Mount(device, target, mType, options string) error {
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 	return mount(device, target, mType, uintptr(flag), data)
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 }
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-// Mount will mount filesystem according to the specified configuration.
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+// ForceMount will mount filesystem according to the specified configuration.
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 // Options must be specified like the mount or fstab unix commands:
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 // "opt1=val1,opt2=val2". See flags.go for supported option flags.
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 //