ceph-csi/pkg/rbd/nodeserver.go

/*
Copyright 2018 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 rbd

import (
	"fmt"
	"os"
	"strings"

	"github.com/golang/glog"
	"golang.org/x/net/context"

	"github.com/container-storage-interface/spec/lib/go/csi"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"

	"k8s.io/kubernetes/pkg/util/mount"

	"github.com/kubernetes-csi/drivers/pkg/csi-common"
)

type nodeServer struct {
	*csicommon.DefaultNodeServer
	mounter mount.Interface
}

func (ns *nodeServer) NodePublishVolume(ctx context.Context, req *csi.NodePublishVolumeRequest) (*csi.NodePublishVolumeResponse, error) {
	targetPath := req.GetTargetPath()
	targetPathMutex.LockKey(targetPath)
	defer targetPathMutex.UnlockKey(targetPath)

	var volName string
	isBlock := req.GetVolumeCapability().GetBlock() != nil

	if isBlock {
		// Get volName from targetPath
		s := strings.Split(targetPath, "/")
		volName = s[len(s)-1]
	} else {
		// Get volName from targetPath
		if !strings.HasSuffix(targetPath, "/mount") {
			return nil, fmt.Errorf("rnd: malformed the value of target path: %s", targetPath)
		}
		s := strings.Split(strings.TrimSuffix(targetPath, "/mount"), "/")
		volName = s[len(s)-1]
	}

	// Check if that target path exists properly
	// IsLikelyNotMountPoint doesn't return right result to bind mount of device file
	// TODO: Need to fix this to a proper check
	notMnt, err := ns.mounter.IsLikelyNotMountPoint(targetPath)
	if err != nil {
		if os.IsNotExist(err) {
			if isBlock {
				// create an empty file
				targetPathFile, err := os.OpenFile(targetPath, os.O_CREATE|os.O_RDWR, 0750)
				if err != nil {
					glog.V(4).Infof("Failed to create targetPath:%s with error: %v", targetPath, err)
					return nil, status.Error(codes.Internal, err.Error())
				}
				if err := targetPathFile.Close(); err != nil {
					glog.V(4).Infof("Failed to close targetPath:%s with error: %v", targetPath, err)
					return nil, status.Error(codes.Internal, err.Error())
				}
			} else {
				// Create a directory
				if err = os.MkdirAll(targetPath, 0750); err != nil {
					return nil, status.Error(codes.Internal, err.Error())
				}
			}
			notMnt = true
		} else {
			return nil, status.Error(codes.Internal, err.Error())
		}
	}

	if !notMnt {
		return &csi.NodePublishVolumeResponse{}, nil
	}
	volOptions, err := getRBDVolumeOptions(req.GetVolumeContext())
	if err != nil {
		return nil, err
	}
	volOptions.VolName = volName
	// Mapping RBD image
	devicePath, err := attachRBDImage(volOptions, volOptions.UserId, req.GetSecrets())
	if err != nil {
		return nil, err
	}
	glog.V(4).Infof("rbd image: %s/%s was successfully mapped at %s\n", req.GetVolumeId(), volOptions.Pool, devicePath)

	// Publish Path
	fsType := req.GetVolumeCapability().GetMount().GetFsType()
	readOnly := req.GetReadonly()
	attrib := req.GetVolumeContext()
	mountFlags := req.GetVolumeCapability().GetMount().GetMountFlags()

	glog.V(4).Infof("target %v\nisBlock %v\nfstype %v\ndevice %v\nreadonly %v\nattributes %v\n mountflags %v\n",
		targetPath, isBlock, fsType, devicePath, readOnly, attrib, mountFlags)

	diskMounter := &mount.SafeFormatAndMount{Interface: ns.mounter, Exec: mount.NewOsExec()}
	if isBlock {
		options := []string{"bind"}
		if err := diskMounter.Mount(devicePath, targetPath, fsType, options); err != nil {
			return nil, err
		}
	} else {
		options := []string{}
		if readOnly {
			options = append(options, "ro")
		}

		if err := diskMounter.FormatAndMount(devicePath, targetPath, fsType, options); err != nil {
			return nil, err
		}
	}

	return &csi.NodePublishVolumeResponse{}, nil
}

func (ns *nodeServer) NodeUnpublishVolume(ctx context.Context, req *csi.NodeUnpublishVolumeRequest) (*csi.NodeUnpublishVolumeResponse, error) {
	targetPath := req.GetTargetPath()
	targetPathMutex.LockKey(targetPath)
	defer targetPathMutex.UnlockKey(targetPath)

	// IsLikelyNotMountPoint doesn't return right result to bind mount of device file
	// So, just use it to check if file exists, not a mount point
	// TODO: Need to fix this to a proper check
	_, err := ns.mounter.IsLikelyNotMountPoint(targetPath)
	if err != nil {
		if os.IsNotExist(err) {
			// targetPath has already been deleted
			glog.V(4).Infof("targetPath: %s has already been deleted", targetPath)
			return &csi.NodeUnpublishVolumeResponse{}, nil
		}
		return nil, status.Error(codes.NotFound, err.Error())
	}

	devicePath, cnt, err := mount.GetDeviceNameFromMount(ns.mounter, targetPath)
	if err != nil {
		return nil, status.Error(codes.Internal, err.Error())
	}

	// Unmounting the image
	err = ns.mounter.Unmount(targetPath)
	if err != nil {
		glog.V(3).Infof("failed to unmount targetPath: %s with error: %v", targetPath, err)
		return nil, status.Error(codes.Internal, err.Error())
	}

	cnt--
	if cnt != 0 {
		return &csi.NodeUnpublishVolumeResponse{}, nil
	}

	// Unmapping rbd device
	if err := detachRBDDevice(devicePath); err != nil {
		glog.V(3).Infof("failed to unmap rbd device: %s with error: %v", devicePath, err)
		return nil, err
	}

	// Remove targetPath
	if err := os.RemoveAll(targetPath); err != nil {
		glog.V(3).Infof("failed to remove targetPath: %s with error: %v", targetPath, err)
		return nil, err
	}

	return &csi.NodeUnpublishVolumeResponse{}, nil
}

func (ns *nodeServer) NodeStageVolume(
	ctx context.Context,
	req *csi.NodeStageVolumeRequest) (
	*csi.NodeStageVolumeResponse, error) {

	return nil, status.Error(codes.Unimplemented, "")
}

func (ns *nodeServer) NodeUnstageVolume(
	ctx context.Context,
	req *csi.NodeUnstageVolumeRequest) (
	*csi.NodeUnstageVolumeResponse, error) {

	return nil, status.Error(codes.Unimplemented, "")
}