snapshot/devmapper: use losetup in mount package

No need to use the private losetup command line wrapper package.
The generic package provides the same functionality.

Signed-off-by: Peng Tao <bergwolf@hyper.sh>
This commit is contained in:
Peng Tao 2020-04-14 00:37:54 -07:00 committed by Maksym Pavlenko
parent 9e42070169
commit b7026236f4
5 changed files with 8 additions and 229 deletions

View File

@ -29,8 +29,8 @@ import (
"gotest.tools/v3/assert"
is "gotest.tools/v3/assert/cmp"
"github.com/containerd/containerd/mount"
"github.com/containerd/containerd/pkg/testutil"
"github.com/containerd/containerd/snapshots/devmapper/losetup"
)
const (
@ -55,16 +55,13 @@ func TestDMSetup(t *testing.T) {
metaImage, loopMetaDevice := createLoopbackDevice(t, tempDir)
defer func() {
err = losetup.RemoveLoopDevicesAssociatedWithImage(dataImage)
assert.NilError(t, err, "failed to detach loop devices for data image: %s", dataImage)
err = losetup.RemoveLoopDevicesAssociatedWithImage(metaImage)
assert.NilError(t, err, "failed to detach loop devices for meta image: %s", metaImage)
err = mount.DetachLoopDevice(loopDataDevice, loopMetaDevice)
assert.NilError(t, err, "failed to detach loop devices for data image: %s and meta image: %s", dataImage, metaImage)
}()
t.Run("CreatePool", func(t *testing.T) {
err := CreatePool(testPoolName, loopDataDevice, loopMetaDevice, 128)
assert.NilError(t, err, "failed to create thin-pool")
assert.NilError(t, err, "failed to create thin-pool with %s %s", loopDataDevice, loopMetaDevice)
table, err := Table(testPoolName)
t.Logf("table: %s", table)
@ -201,7 +198,7 @@ func createLoopbackDevice(t *testing.T, dir string) (string, string) {
imagePath := file.Name()
loopDevice, err := losetup.AttachLoopDevice(imagePath)
loopDevice, err := mount.AttachLoopDevice(imagePath)
assert.NilError(t, err)
return imagePath, loopDevice

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@ -1,92 +0,0 @@
// +build linux
/*
Copyright The containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package losetup
import (
"os/exec"
"strings"
"github.com/pkg/errors"
"golang.org/x/sys/unix"
)
// FindAssociatedLoopDevices returns a list of loop devices attached to a given image
func FindAssociatedLoopDevices(imagePath string) ([]string, error) {
output, err := losetup("--list", "--output", "NAME", "--associated", imagePath)
if err != nil {
return nil, errors.Wrapf(err, "failed to get loop devices: '%s'", output)
}
if output == "" {
return []string{}, nil
}
items := strings.Split(output, "\n")
if len(items) <= 1 {
return []string{}, nil
}
// Skip header with column names
return items[1:], nil
}
// AttachLoopDevice finds first available loop device and associates it with an image.
func AttachLoopDevice(imagePath string) (string, error) {
return losetup("--find", "--show", imagePath)
}
// DetachLoopDevice detaches loop devices
func DetachLoopDevice(loopDevice ...string) error {
args := append([]string{"--detach"}, loopDevice...)
_, err := losetup(args...)
return err
}
// RemoveLoopDevicesAssociatedWithImage detaches all loop devices attached to a given sparse image
func RemoveLoopDevicesAssociatedWithImage(imagePath string) error {
loopDevices, err := FindAssociatedLoopDevices(imagePath)
if err != nil {
return err
}
for _, loopDevice := range loopDevices {
if err = DetachLoopDevice(loopDevice); err != nil && err != unix.ENOENT {
return err
}
}
return nil
}
// losetup is a wrapper around losetup command line tool
func losetup(args ...string) (string, error) {
cmd := exec.Command("losetup", args...)
cmd.Env = append(cmd.Env, "LANG=C")
data, err := cmd.CombinedOutput()
output := string(data)
if err != nil {
if strings.Contains(output, "No such file or directory") || strings.Contains(output, "No such device") {
return "", unix.ENOENT
}
return "", errors.Wrapf(err, "losetup %s\nerror: %s\n", strings.Join(args, " "), output)
}
return strings.TrimSuffix(output, "\n"), err
}

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@ -1,124 +0,0 @@
// +build linux
/*
Copyright The containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package losetup
import (
"io/ioutil"
"os"
"testing"
"github.com/docker/go-units"
"golang.org/x/sys/unix"
"gotest.tools/v3/assert"
is "gotest.tools/v3/assert/cmp"
"github.com/containerd/containerd/pkg/testutil"
)
func TestLosetup(t *testing.T) {
testutil.RequiresRoot(t)
var (
imagePath = createSparseImage(t)
loopDevice1 string
loopDevice2 string
)
defer func() {
err := os.Remove(imagePath)
assert.NilError(t, err)
}()
t.Run("AttachLoopDevice", func(t *testing.T) {
dev1, err := AttachLoopDevice(imagePath)
assert.NilError(t, err)
assert.Assert(t, dev1 != "")
dev2, err := AttachLoopDevice(imagePath)
assert.NilError(t, err)
assert.Assert(t, dev2 != dev1, "should attach different loop device")
loopDevice1 = dev1
loopDevice2 = dev2
})
t.Run("AttachEmptyLoopDevice", func(t *testing.T) {
_, err := AttachLoopDevice("")
assert.Assert(t, err != nil, "shouldn't attach empty path")
})
t.Run("FindAssociatedLoopDevices", func(t *testing.T) {
devices, err := FindAssociatedLoopDevices(imagePath)
assert.NilError(t, err)
assert.Assert(t, is.Len(devices, 2), "unexpected number of attached devices")
assert.Assert(t, is.Contains(devices, loopDevice1))
assert.Assert(t, is.Contains(devices, loopDevice2))
})
t.Run("FindAssociatedLoopDevicesForInvalidImage", func(t *testing.T) {
devices, err := FindAssociatedLoopDevices("")
assert.NilError(t, err)
assert.Assert(t, is.Len(devices, 0))
})
t.Run("DetachLoopDevice", func(t *testing.T) {
err := DetachLoopDevice(loopDevice2)
assert.NilError(t, err, "failed to detach %q", loopDevice2)
})
t.Run("DetachEmptyDevice", func(t *testing.T) {
err := DetachLoopDevice("")
assert.Assert(t, err != nil, "shouldn't detach empty path")
})
t.Run("RemoveLoopDevicesAssociatedWithImage", func(t *testing.T) {
err := RemoveLoopDevicesAssociatedWithImage(imagePath)
assert.NilError(t, err)
devices, err := FindAssociatedLoopDevices(imagePath)
assert.NilError(t, err)
assert.Assert(t, is.Len(devices, 0))
})
t.Run("RemoveLoopDevicesAssociatedWithInvalidImage", func(t *testing.T) {
err := RemoveLoopDevicesAssociatedWithImage("")
assert.NilError(t, err)
})
t.Run("DetachInvalidDevice", func(t *testing.T) {
err := DetachLoopDevice("/dev/loop_invalid_idx")
assert.Equal(t, unix.ENOENT, err)
})
}
func createSparseImage(t *testing.T) string {
file, err := ioutil.TempFile("", "losetup-tests-")
assert.NilError(t, err)
size, err := units.RAMInBytes("16Mb")
assert.NilError(t, err)
err = file.Truncate(size)
assert.NilError(t, err)
err = file.Close()
assert.NilError(t, err)
return file.Name()
}

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@ -31,7 +31,6 @@ import (
"github.com/containerd/containerd/mount"
"github.com/containerd/containerd/pkg/testutil"
"github.com/containerd/containerd/snapshots/devmapper/dmsetup"
"github.com/containerd/containerd/snapshots/devmapper/losetup"
"github.com/docker/go-units"
"github.com/sirupsen/logrus"
"gotest.tools/v3/assert"
@ -74,7 +73,7 @@ func TestPoolDevice(t *testing.T) {
defer func() {
// Detach loop devices and remove images
err := losetup.DetachLoopDevice(loopDataDevice, loopMetaDevice)
err := mount.DetachLoopDevice(loopDataDevice, loopMetaDevice)
assert.NilError(t, err)
err = os.RemoveAll(tempDir)
@ -306,7 +305,7 @@ func createLoopbackDevice(t *testing.T, dir string) (string, string) {
imagePath := file.Name()
loopDevice, err := losetup.AttachLoopDevice(imagePath)
loopDevice, err := mount.AttachLoopDevice(imagePath)
assert.NilError(t, err)
return imagePath, loopDevice

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@ -37,7 +37,6 @@ import (
"github.com/containerd/containerd/pkg/testutil"
"github.com/containerd/containerd/snapshots"
"github.com/containerd/containerd/snapshots/devmapper/dmsetup"
"github.com/containerd/containerd/snapshots/devmapper/losetup"
"github.com/containerd/containerd/snapshots/testsuite"
)
@ -70,7 +69,7 @@ func TestSnapshotterSuite(t *testing.T) {
removePool := func() error {
result := multierror.Append(
snap.pool.RemovePool(ctx),
losetup.DetachLoopDevice(loopDataDevice, loopMetaDevice))
mount.DetachLoopDevice(loopDataDevice, loopMetaDevice))
return result.ErrorOrNil()
}