Add support for windows to AWS EBS

pkg/volume/awsebs/BUILD

@@ -10,6 +10,9 @@ go_library(
     name = "go_default_library",
     srcs = [
         "attacher.go",
+        "attacher_linux.go",
+        "attacher_unsupported.go",
+        "attacher_windows.go",
         "aws_ebs.go",
         "aws_ebs_block.go",
         "aws_util.go",

pkg/volume/awsebs/attacher.go

@@ -20,6 +20,8 @@ import (
 	"fmt"
 	"os"
 	"path"
+	"path/filepath"
+	"runtime"
 	"strconv"
 	"time"
 
@@ -175,15 +177,14 @@ func (attacher *awsElasticBlockStoreAttacher) WaitForAttach(spec *volume.Spec, d
 	for {
 		select {
 		case <-ticker.C:
-			klog.V(5).Infof("Checking AWS Volume %q is attached.", volumeID)
-			devicePaths := getDiskByIDPaths(aws.KubernetesVolumeID(volumeSource.VolumeID), partition, devicePath)
-			path, err := verifyDevicePath(devicePaths)
+			klog.V(5).Infof("Checking AWS Volume %q is attached at devicePath %q.", volumeID, devicePath)
+			path, err := attacher.getDevicePath(volumeSource.VolumeID, partition, devicePath)
 			if err != nil {
 				// Log error, if any, and continue checking periodically. See issue #11321
-				klog.Errorf("Error verifying AWS Volume (%q) is attached: %v", volumeID, err)
+				klog.Errorf("Error verifying AWS Volume (%q) is attached at devicePath %q: %v", volumeID, devicePath, err)
 			} else if path != "" {
 				// A device path has successfully been created for the PD
-				klog.Infof("Successfully found attached AWS Volume %q.", volumeID)
+				klog.Infof("Successfully found attached AWS Volume %q at path %q.", volumeID, path)
 				return path, nil
 			}
 		case <-timer.C:
@@ -208,8 +209,17 @@ func (attacher *awsElasticBlockStoreAttacher) MountDevice(spec *volume.Spec, dev
 	notMnt, err := mounter.IsLikelyNotMountPoint(deviceMountPath)
 	if err != nil {
 		if os.IsNotExist(err) {
-			if err := os.MkdirAll(deviceMountPath, 0750); err != nil {
-				return err
+			dir := deviceMountPath
+			if runtime.GOOS == "windows" {
+				// On Windows, FormatAndMount will mklink (create a symbolic link) at deviceMountPath later, so don't create a
+				// directory at deviceMountPath now. Otherwise mklink will error: "Cannot create a file when that file already exists".
+				// Instead, create the parent of deviceMountPath. For example when deviceMountPath is:
+				// C:\var\lib\kubelet\plugins\kubernetes.io\aws-ebs\mounts\aws\us-west-2b\vol-xxx
+				// create us-west-2b. FormatAndMount will make vol-xxx a symlink to the drive (e.g. D:\)
+				dir = filepath.Dir(deviceMountPath)
+			}
+			if err := os.MkdirAll(dir, 0750); err != nil {
+				return fmt.Errorf("making dir %s failed with %s", dir, err)
 			}
 			notMnt = true
 		} else {

pkg/volume/awsebs/attacher_linux.go

@@ -0,0 +1,28 @@
+// +build linux
+
+/*
+Copyright 2019 The Kubernetes 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 awsebs
+
+import (
+	"k8s.io/legacy-cloud-providers/aws"
+)
+
+func (attacher *awsElasticBlockStoreAttacher) getDevicePath(volumeID, partition, devicePath string) (string, error) {
+	devicePaths := getDiskByIDPaths(aws.KubernetesVolumeID(volumeID), partition, devicePath)
+	return verifyDevicePath(devicePaths)
+}

pkg/volume/awsebs/attacher_unsupported.go

@@ -0,0 +1,25 @@
+// +build !linux,!windows
+
+/*
+Copyright 2019 The Kubernetes 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 awsebs
+
+import "errors"
+
+func (attacher *awsElasticBlockStoreAttacher) getDevicePath(volumeID, partition, devicePath string) (string, error) {
+	return "", errors.New("unsupported")
+}

pkg/volume/awsebs/attacher_windows.go

@@ -0,0 +1,68 @@
+// +build windows
+
+/*
+Copyright 2019 The Kubernetes 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 awsebs
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+)
+
+// ebsnvme-id is present on AWS-provided Windows Server AMIs
+// https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/nvme-ebs-volumes.html#identify-nvme-ebs-device
+const ebsnvmeID = `C:\ProgramData\Amazon\Tools\ebsnvme-id.exe`
+
+func (attacher *awsElasticBlockStoreAttacher) getDevicePath(volumeID, partition, devicePath string) (string, error) {
+	return attacher.getDiskNumber(volumeID)
+}
+
+// getDiskNumber gets the Windows disk number for a given volume ID. The disk number is needed for mounting.
+// TODO This only works for Nitro-based instances
+// TODO fallback to Get-Disk
+func (attacher *awsElasticBlockStoreAttacher) getDiskNumber(volumeID string) (string, error) {
+	// Split the ID from zone: aws://us-west-2b/vol-06d0909eb358b05f9
+	split := strings.Split(volumeID, "/")
+	volumeID = split[len(split)-1]
+
+	exec := attacher.host.GetExec(awsElasticBlockStorePluginName)
+	output, err := exec.Run(ebsnvmeID)
+	if err != nil {
+		return "", fmt.Errorf("error calling ebsnvme-id.exe: %v", err)
+	}
+	// ebsnvme-id.exe will output a list of disks in this format:
+	// ```
+	// Disk Number: 1
+	// Volume ID: vol-06d0909eb358b05f9
+	// Device Name: /dev/xvdch
+	// ```
+	// Don't try to match devicePath against "Device Name" not only because volume ID is sufficient,
+	// but because devicePath may change between Linux & Windows formats between WaitForAttach calls.
+	// The first attach and mount, WaitForAttach gets devicePath as the Linux format /dev/xvdch. Then
+	// WaitForAttach returns the disk number as the "right" devicePath and that is persisted to ASW.
+	// In subsequent mounts of the same disk, WaitForAttach gets devicePath as the Windows format it
+	// returned the first time.
+	diskRe := regexp.MustCompile(
+		`Disk Number: (\d+)\s*` +
+			`Volume ID: ` + volumeID + `\s*`)
+	matches := diskRe.FindStringSubmatch(string(output))
+	if len(matches) != 2 {
+		return "", fmt.Errorf("disk not found in ebsnvme-id.exe output: %q", string(output))
+	}
+	return matches[1], nil
+}

pkg/volume/awsebs/aws_ebs.go

@@ -22,6 +22,7 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"runtime"
 	"strconv"
 	"strings"
 
@@ -401,8 +402,15 @@ func (b *awsElasticBlockStoreMounter) SetUpAt(dir string, mounterArgs volume.Mou
 
 	globalPDPath := makeGlobalPDPath(b.plugin.host, b.volumeID)
 
-	if err := os.MkdirAll(dir, 0750); err != nil {
-		return err
+	if runtime.GOOS != "windows" {
+		// On Windows, Mount will create the parent of dir and mklink (create a symbolic link) at dir later, so don't create a
+		// directory at dir now. Otherwise mklink will error: "Cannot create a file when that file already exists".
+		// Instead, do nothing. For example when dir is:
+		// C:\var\lib\kubelet\pods\xxx\volumes\kubernetes.io~aws-ebs\pvc-xxx
+		// do nothing. Mount will make pvc-xxx a symlink to the global mount path (e.g. C:\var\lib\kubelet\plugins\kubernetes.io\aws-ebs\mounts\aws\us-west-2b\vol-xxx)
+		if err := os.MkdirAll(dir, 0750); err != nil {
+			return err
+		}
 	}
 
 	// Perform a bind mount to the full path to allow duplicate mounts of the same PD.