Rename aws_pd -> aws_ebs

pkg/volume/aws_ebs/aws_util.go

@@ -0,0 +1,143 @@
+/*
+Copyright 2014 Google Inc. All rights reserved.
+
+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 aws_ebs
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"time"
+
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/util/exec"
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/util/mount"
+	"github.com/golang/glog"
+)
+
+type AWSDiskUtil struct{}
+
+// Attaches a disk specified by a volume.AWSElasticBlockStore to the current kubelet.
+// Mounts the disk to it's global path.
+func (util *AWSDiskUtil) AttachAndMountDisk(pd *awsElasticBlockStore, globalPDPath string) error {
+	volumes, err := pd.getVolumeProvider()
+	if err != nil {
+		return err
+	}
+	flags := uintptr(0)
+	if pd.readOnly {
+		flags = mount.FlagReadOnly
+	}
+	devicePath, err := volumes.AttachDisk("", pd.volumeID, pd.readOnly)
+	if err != nil {
+		return err
+	}
+	if pd.partition != "" {
+		devicePath = devicePath + pd.partition
+	}
+	//TODO(jonesdl) There should probably be better method than busy-waiting here.
+	numTries := 0
+	for {
+		_, err := os.Stat(devicePath)
+		if err == nil {
+			break
+		}
+		if err != nil && !os.IsNotExist(err) {
+			return err
+		}
+		numTries++
+		if numTries == 10 {
+			return errors.New("Could not attach disk: Timeout after 10s (" + devicePath + ")")
+		}
+		time.Sleep(time.Second)
+	}
+
+	// Only mount the PD globally once.
+	mountpoint, err := pd.mounter.IsMountPoint(globalPDPath)
+	if err != nil {
+		if os.IsNotExist(err) {
+			if err := os.MkdirAll(globalPDPath, 0750); err != nil {
+				return err
+			}
+			mountpoint = false
+		} else {
+			return err
+		}
+	}
+	if !mountpoint {
+		err = pd.diskMounter.Mount(devicePath, globalPDPath, pd.fsType, flags, "")
+		if err != nil {
+			os.Remove(globalPDPath)
+			return err
+		}
+	}
+	return nil
+}
+
+// Unmounts the device and detaches the disk from the kubelet's host machine.
+func (util *AWSDiskUtil) DetachDisk(pd *awsElasticBlockStore) error {
+	// Unmount the global PD mount, which should be the only one.
+	globalPDPath := makeGlobalPDPath(pd.plugin.host, pd.volumeID)
+	if err := pd.mounter.Unmount(globalPDPath, 0); err != nil {
+		glog.V(2).Info("Error unmount dir ", globalPDPath, ": ", err)
+		return err
+	}
+	if err := os.Remove(globalPDPath); err != nil {
+		glog.V(2).Info("Error removing dir ", globalPDPath, ": ", err)
+		return err
+	}
+	// Detach the disk
+	volumes, err := pd.getVolumeProvider()
+	if err != nil {
+		glog.V(2).Info("Error getting volume provider for volumeID ", pd.volumeID, ": ", err)
+		return err
+	}
+	if err := volumes.DetachDisk("", pd.volumeID); err != nil {
+		glog.V(2).Info("Error detaching disk ", pd.volumeID, ": ", err)
+		return err
+	}
+	return nil
+}
+
+// safe_format_and_mount is a utility script on AWS VMs that probes a persistent disk, and if
+// necessary formats it before mounting it.
+// This eliminates the necessity to format a PD before it is used with a Pod on AWS.
+// TODO: port this script into Go and use it for all Linux platforms
+type awsSafeFormatAndMount struct {
+	mount.Interface
+	runner exec.Interface
+}
+
+// uses /usr/share/google/safe_format_and_mount to optionally mount, and format a disk
+func (mounter *awsSafeFormatAndMount) Mount(source string, target string, fstype string, flags uintptr, data string) error {
+	// Don't attempt to format if mounting as readonly. Go straight to mounting.
+	if (flags & mount.FlagReadOnly) != 0 {
+		return mounter.Interface.Mount(source, target, fstype, flags, data)
+	}
+	args := []string{}
+	// ext4 is the default for safe_format_and_mount
+	if len(fstype) > 0 && fstype != "ext4" {
+		args = append(args, "-m", fmt.Sprintf("mkfs.%s", fstype))
+	}
+	args = append(args, source, target)
+	// TODO: Accept other options here?
+	glog.V(5).Infof("exec-ing: /usr/share/google/safe_format_and_mount %v", args)
+	cmd := mounter.runner.Command("/usr/share/google/safe_format_and_mount", args...)
+	dataOut, err := cmd.CombinedOutput()
+	if err != nil {
+		glog.V(5).Infof("error running /usr/share/google/safe_format_and_mount\n%s", string(dataOut))
+	}
+	return err
+}