daemon.go

/*
Copyright 2016 The Rook Authors. 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 osd

import (
	"fmt"
	"io/ioutil"
	"os"
	"os/signal"
	"regexp"
	"strconv"
	"syscall"
	"time"

	"strings"

	"github.com/coreos/pkg/capnslog"
	"github.com/rook/rook/pkg/clusterd"
	cephconfig "github.com/rook/rook/pkg/daemon/ceph/config"
	oposd "github.com/rook/rook/pkg/operator/ceph/cluster/osd"
	"github.com/rook/rook/pkg/operator/ceph/cluster/osd/config"
	"github.com/rook/rook/pkg/operator/k8sutil"
	"github.com/rook/rook/pkg/util/sys"
	"k8s.io/apimachinery/pkg/api/errors"
)

var (
	logger = capnslog.NewPackageLogger("github.com/rook/rook", "cephosd")
)

// StartOSD starts an OSD on a device that was provisioned by ceph-volume
func StartOSD(context *clusterd.Context, osdType, osdID, osdUUID, lvPath string, pvcBackedOSD bool, cephArgs []string) error {

	// ensure the config mount point exists
	configDir := fmt.Sprintf("/var/lib/ceph/osd/ceph-%s", osdID)
	err := os.Mkdir(configDir, 0755)
	if err != nil {
		logger.Errorf("failed to create config dir %s. %+v", configDir, err)
	}

	// Update LVM config at runtime
	if err := updateLVMConfig(context, pvcBackedOSD); err != nil {
		return fmt.Errorf("sed failure, %+v", err) // fail return here as validation provided by ceph-volume
	}

	var volumeGroupName string
	if pvcBackedOSD {
		volumeGroupName, err = getVolumeGroupName(lvPath)
		if err != nil {
			return fmt.Errorf("error fetching volume group name for OSD %s. %+v", osdID, err)
		}
		go handleTerminate(context, lvPath, volumeGroupName)

		if err := context.Executor.ExecuteCommand(false, "", "vgchange", "-an", volumeGroupName); err != nil {
			return fmt.Errorf("failed to deactivate volume group for lv %+v. Error: %+v", lvPath, err)
		}

		if err := context.Executor.ExecuteCommand(false, "", "vgchange", "-ay", volumeGroupName); err != nil {
			return fmt.Errorf("failed to activate volume group for lv %+v. Error: %+v", lvPath, err)
		}
	}

	// activate the osd with ceph-volume
	storeFlag := "--" + osdType
	if err := context.Executor.ExecuteCommand(false, "", "stdbuf", "-oL", "ceph-volume", "lvm", "activate", "--no-systemd", storeFlag, osdID, osdUUID); err != nil {
		return fmt.Errorf("failed to activate osd. %+v", err)
	}

	// run the ceph-osd daemon
	if err := context.Executor.ExecuteCommand(false, "", "ceph-osd", cephArgs...); err != nil {
		return fmt.Errorf("failed to start osd. %+v", err)
	}

	if pvcBackedOSD {
		if err := releaseLVMDevice(context, volumeGroupName); err != nil {
			return fmt.Errorf("failed to release device from lvm. %+v", err)
		}

	}

	return nil
}

func handleTerminate(context *clusterd.Context, lvPath, volumeGroupName string) error {
	sigc := make(chan os.Signal, 1)
	signal.Notify(sigc, syscall.SIGTERM)
	for {
		select {
		case <-sigc:
			logger.Infof("shutdown signal received, exiting...")
			err := killCephOSDProcess(context, lvPath)
			if err != nil {
				return fmt.Errorf("failed to kill ceph-osd process. %+v", err)
			}
			if err := releaseLVMDevice(context, volumeGroupName); err != nil {
				return fmt.Errorf("failed to release device from lvm. %+v", err)
			}
			return nil
		}
	}
}

func killCephOSDProcess(context *clusterd.Context, lvPath string) error {

	processKilled := false
	pid, err := context.Executor.ExecuteCommandWithOutput(false, "", "fuser", "-a", lvPath)
	if err != nil {
		return fmt.Errorf("failed to retrieve process ID for - %s. Error %+v", lvPath, err)
	}

	logger.Debugf("process ID for ceph-osd: %s", pid)

	// shut down the osd-ceph process so that lvm release does not show device in use error.
	if pid != "" {
		if err := context.Executor.ExecuteCommand(false, "", "kill", pid); err != nil {
			return fmt.Errorf("failed to delete ceph-osd process. %+v", err)
		}
	} else {
		return nil
	}

	pidInt, err := strconv.Atoi(pid)
	if err != nil {
		return fmt.Errorf("failed to convert process ID - %s to string. Error %+v ", pid, err)
	}
	for !processKilled {
		_, err := os.FindProcess(int(pidInt))
		if err != nil {
			logger.Infof("ceph-osd process deleted successfully")
			processKilled = true
		} else {
			logger.Infof("ceph-osd process still running")
			time.Sleep(2 * time.Second)
			continue
		}
	}

	return nil
}

func RunFilestoreOnDevice(context *clusterd.Context, mountSourcePath, mountPath string, cephArgs []string) error {
	// start the OSD daemon in the foreground with the given config
	logger.Infof("starting filestore osd on a device")

	if err := sys.MountDevice(mountSourcePath, mountPath, context.Executor); err != nil {
		return fmt.Errorf("failed to mount device. %+v", err)
	}
	// unmount the device before exit
	defer sys.UnmountDevice(mountPath, context.Executor)

	// run the ceph-osd daemon
	if err := context.Executor.ExecuteCommand(false, "", "ceph-osd", cephArgs...); err != nil {
		return fmt.Errorf("failed to start osd. %+v", err)
	}

	return nil
}

func Provision(context *clusterd.Context, agent *OsdAgent) error {
	// set the initial orchestration status
	status := oposd.OrchestrationStatus{Status: oposd.OrchestrationStatusComputingDiff}
	if err := oposd.UpdateNodeStatus(agent.kv, agent.nodeName, status); err != nil {
		return err
	}

	// set the crush location in the osd config file
	cephConfig, err := cephconfig.CreateDefaultCephConfig(context, agent.cluster)
	if err != nil {
		return fmt.Errorf("failed to create default ceph config. %+v", err)
	}
	cephConfig.GlobalConfig.CrushLocation = agent.location

	// write the latest config to the config dir
	confFilePath, err := cephconfig.GenerateAdminConnectionConfigWithSettings(context, agent.cluster, cephConfig)
	if err != nil {
		return fmt.Errorf("failed to write connection config. %+v", err)
	}
	src, err := ioutil.ReadFile(confFilePath)
	if err != nil {
		return fmt.Errorf("failed to copy connection config to /etc/ceph. failed to read the connection config. %+v", err)
	}
	err = ioutil.WriteFile(cephconfig.DefaultConfigFilePath(), src, 0444)
	if err != nil {
		return fmt.Errorf("failed to copy connection config to /etc/ceph. failed to write %s. %+v", cephconfig.DefaultConfigFilePath(), err)
	}
	dst, err := ioutil.ReadFile(cephconfig.DefaultConfigFilePath())
	if err == nil {
		logger.Debugf("config file @ %s: %s", cephconfig.DefaultConfigFilePath(), dst)
	} else {
		logger.Warningf("wrote and copied config file but failed to read it back from %s for logging. %+v", cephconfig.DefaultConfigFilePath(), err)
	}

	logger.Infof("discovering hardware")
	var rawDevices []*sys.LocalDisk
	if agent.pvcBacked {
		if len(agent.devices) > 1 {
			return fmt.Errorf("more than one desired device found in case of PVC backed OSDs. we expect exactly one device")
		}
		rawDevices = append(rawDevices, clusterd.PopulateDeviceInfo(agent.devices[0].Name, context.Executor))
	} else {
		rawDevices, err = clusterd.DiscoverDevices(context.Executor)
		if err != nil {
			return fmt.Errorf("failed initial hardware discovery. %+v", err)
		}
	}

	context.Devices = rawDevices

	logger.Infof("creating and starting the osds")

	// determine the set of devices that can/should be used for OSDs.
	devices, err := getAvailableDevices(context, agent.devices, agent.metadataDevice, agent.pvcBacked)
	if err != nil {
		return fmt.Errorf("failed to get available devices. %+v", err)
	}

	// determine the set of removed OSDs and the node's crush name (if needed)
	removedDevicesScheme, _, err := getRemovedDevices(agent)
	if err != nil {
		return fmt.Errorf("failed to get removed devices: %+v", err)
	}

	// orchestration is about to start, update the status
	status = oposd.OrchestrationStatus{Status: oposd.OrchestrationStatusOrchestrating, PvcBackedOSD: agent.pvcBacked}
	if err := oposd.UpdateNodeStatus(agent.kv, agent.nodeName, status); err != nil {
		return err
	}

	// start the desired OSDs on devices
	logger.Infof("configuring osd devices: %+v", devices)
	deviceOSDs, err := agent.configureDevices(context, devices)
	if err != nil {
		return fmt.Errorf("failed to configure devices. %+v", err)
	}

	// determine the set of directories that can/should be used for OSDs, with the default dir if no devices were specified. save off the node's crush name if needed.
	logger.Infof("devices = %+v", deviceOSDs)
	devicesConfigured := len(deviceOSDs) > 0
	dirs, removedDirs, err := getDataDirs(context, agent.kv, agent.directories, devicesConfigured, agent.nodeName)
	if err != nil {
		return fmt.Errorf("failed to get data dirs. %+v", err)
	}

	// start up the OSDs for directories
	logger.Infof("configuring osd dirs: %+v", dirs)
	dirOSDs, err := agent.configureDirs(context, dirs)
	if err != nil {
		return fmt.Errorf("failed to configure dirs %+v. %+v", dirs, err)
	}

	// now we can start removing OSDs from devices and directories
	logger.Infof("removing osd devices: %+v", removedDevicesScheme)
	if err := agent.removeDevices(context, removedDevicesScheme); err != nil {
		return fmt.Errorf("failed to remove devices. %+v", err)
	}

	logger.Infof("removing osd dirs: %+v", removedDirs)
	if err := agent.removeDirs(context, removedDirs); err != nil {
		return fmt.Errorf("failed to remove dirs. %+v", err)
	}

	logger.Info("saving osd dir map")
	if err := config.SaveOSDDirMap(agent.kv, agent.nodeName, dirs); err != nil {
		return fmt.Errorf("failed to save osd dir map. %+v", err)
	}

	logger.Infof("device osds:%+v\ndir osds: %+v", deviceOSDs, dirOSDs)

	if agent.pvcBacked && !deviceOSDs[0].SkipLVRelease {
		volumeGroupName, err := getVolumeGroupName(deviceOSDs[0].LVPath)
		if err != nil {
			return fmt.Errorf("error fetching volume group name. %+v", err)
		}
		if err := releaseLVMDevice(context, volumeGroupName); err != nil {
			return fmt.Errorf("failed to release device from lvm. %+v", err)
		}
	}

	osds := append(deviceOSDs, dirOSDs...)

	// orchestration is completed, update the status
	status = oposd.OrchestrationStatus{OSDs: osds, Status: oposd.OrchestrationStatusCompleted, PvcBackedOSD: agent.pvcBacked}
	if err := oposd.UpdateNodeStatus(agent.kv, agent.nodeName, status); err != nil {
		return err
	}

	return nil
}

func getAvailableDevices(context *clusterd.Context, desiredDevices []DesiredDevice, metadataDevice string, pvcBacked bool) (*DeviceOsdMapping, error) {

	available := &DeviceOsdMapping{Entries: map[string]*DeviceOsdIDEntry{}}

	if isRemovingNode(desiredDevices) {
		// the node is being removed, just return an empty set
		return available, nil
	}

	for _, device := range context.Devices {
		if device.Type == sys.PartType {
			continue
		}
		partCount, ownPartitions, fs, err := sys.CheckIfDeviceAvailable(context.Executor, device.Name, pvcBacked)
		if err != nil {
			return nil, fmt.Errorf("failed to get device %s info. %+v", device.Name, err)
		}

		if fs != "" || !ownPartitions {
			// not OK to use the device because it has a filesystem or rook doesn't own all its partitions
			logger.Infof("skipping device %s that is in use (not by rook). fs: %s, ownPartitions: %t", device.Name, fs, ownPartitions)
			continue
		}

		var deviceInfo *DeviceOsdIDEntry
		if metadataDevice != "" && metadataDevice == device.Name {
			// current device is desired as the metadata device
			deviceInfo = &DeviceOsdIDEntry{Data: unassignedOSDID, Metadata: []int{}}
		} else if len(desiredDevices) == 1 && desiredDevices[0].Name == "all" {
			// user has specified all devices, use the current one for data
			deviceInfo = &DeviceOsdIDEntry{Data: unassignedOSDID}
		} else if len(desiredDevices) > 0 {
			var matched bool
			var err error
			var matchedDevice DesiredDevice
			for _, desiredDevice := range desiredDevices {
				if desiredDevice.IsFilter {
					// the desired devices is a regular expression
					matched, err = regexp.Match(desiredDevice.Name, []byte(device.Name))
					if err != nil {
						logger.Errorf("regex failed on device %s and filter %s. %+v", device.Name, desiredDevice.Name, err)
						continue
					}
					logger.Infof("device %s matches device filter %s: %t", device.Name, desiredDevice.Name, matched)
				} else if device.Name == desiredDevice.Name {
					logger.Infof("%s found in the desired devices", device.Name)
					matched = true
				}
				matchedDevice = desiredDevice
				if matched {
					break
				}
			}

			if err == nil && matched {
				// the current device matches the user specifies filter/list, use it for data
				deviceInfo = &DeviceOsdIDEntry{Data: unassignedOSDID, Config: matchedDevice}
			} else {
				logger.Infof("skipping device %s that does not match the device filter/list (%v). %+v", device.Name, desiredDevices, err)
			}
		} else {
			logger.Infof("skipping device %s until the admin specifies it can be used by an osd", device.Name)
		}

		if deviceInfo != nil {
			if partCount > 0 {
				deviceInfo.LegacyPartitionsFound = ownPartitions
			}
			available.Entries[device.Name] = deviceInfo
		}
	}

	return available, nil
}

func isRemovingNode(devices []DesiredDevice) bool {
	if len(devices) != 1 {
		return false
	}
	return oposd.IsRemovingNode(devices[0].Name)
}

func getDataDirs(context *clusterd.Context, kv *k8sutil.ConfigMapKVStore, desiredDirs string,
	devicesSpecified bool, nodeName string) (dirs, removedDirs map[string]int, err error) {

	var dirList []string
	if desiredDirs != "" {
		dirList = strings.Split(desiredDirs, ",")
	}

	// when user has not specified any dirs or any devices, legacy behavior was to give them the
	// default dir. no longer automatically create this fallback osd. the legacy conditional is
	// still important for determining when the fallback osd may be deleted.
	noDirsOrDevicesSpecified := len(dirList) == 0 && !devicesSpecified

	removedDirs = make(map[string]int)

	dirMap, err := config.LoadOSDDirMap(kv, nodeName)
	if err == nil {
		// we have an existing saved dir map, merge the user specified directories into it
		addDirsToDirMap(dirList, &dirMap)

		// determine which dirs are still active, which should be removed, then return them
		activeDirs, removedDirs := getActiveAndRemovedDirs(dirList, dirMap, context.ConfigDir, noDirsOrDevicesSpecified)
		return activeDirs, removedDirs, nil
	}

	if !errors.IsNotFound(err) {
		// real error when trying to load the osd dir map, return the err
		return nil, nil, fmt.Errorf("failed to load OSD dir map: %+v", err)
	}

	// the osd dirs map doesn't exist yet

	if len(dirList) == 0 {
		// no dirs should be used because the user has requested no dirs but they have requested devices
		return map[string]int{}, removedDirs, nil
	}

	// add the specified dirs to the map and return it
	dirMap = make(map[string]int, len(dirList))
	addDirsToDirMap(dirList, &dirMap)
	return dirMap, removedDirs, nil
}

func addDirsToDirMap(dirList []string, dirMap *map[string]int) {
	for _, d := range dirList {
		if _, ok := (*dirMap)[d]; !ok {
			// the users dir isn't already in the map, add it with an unassigned ID
			(*dirMap)[d] = unassignedOSDID
		}
	}
}

func getRemovedDevices(agent *OsdAgent) (*config.PerfScheme, *DeviceOsdMapping, error) {
	removedDevicesScheme := config.NewPerfScheme()
	removedDevicesMapping := &DeviceOsdMapping{Entries: map[string]*DeviceOsdIDEntry{}}

	if !isRemovingNode(agent.devices) {
		// TODO: support more removed device scenarios beyond just entire node removal
		return removedDevicesScheme, removedDevicesMapping, nil
	}

	scheme, err := config.LoadScheme(agent.kv, config.GetConfigStoreName(agent.nodeName))
	if err != nil {
		return nil, nil, fmt.Errorf("failed to load agent's partition scheme: %+v", err)
	}

	for _, entry := range scheme.Entries {
		// determine which partition the data lives on for this entry
		dataDetails, ok := entry.Partitions[entry.GetDataPartitionType()]
		if !ok || dataDetails == nil {
			return nil, nil, fmt.Errorf("failed to find data partition for entry %+v", entry)
		}

		// add the current scheme entry to the removed devices scheme and its device to the removed
		// devices mapping
		removedDevicesScheme.Entries = append(removedDevicesScheme.Entries, entry)
		removedDevicesMapping.Entries[dataDetails.Device] = &DeviceOsdIDEntry{Data: entry.ID}
	}

	return removedDevicesScheme, removedDevicesMapping, nil
}

func getActiveAndRemovedDirs(
	currentDirList []string, savedDirMap map[string]int, configDir string, noDirsOrDevicesSpecified bool,
) (activeDirs, removedDirs map[string]int) {
	activeDirs = map[string]int{}
	removedDirs = map[string]int{}

	for savedDir, id := range savedDirMap {
		foundSavedDir := false

		// If a legacy 'fallback' osd and no dirs/devices are yet specified, keep it to preserve
		// legacy behavior for migrated clusters.
		if savedDir == configDir && noDirsOrDevicesSpecified {
			foundSavedDir = true
		}

		for _, dir := range currentDirList {
			if dir == savedDir {
				foundSavedDir = true
				break
			}
		}

		if foundSavedDir {
			// the saved dir is still active
			activeDirs[savedDir] = id
		} else {
			// the saved dir was not found in the current dir list, meaning the user wants this dir removed
			removedDirs[savedDir] = id
		}
	}

	return activeDirs, removedDirs
}

//releaseLVMDevice deactivates the LV to release the device.
func releaseLVMDevice(context *clusterd.Context, volumeGroupName string) error {
	if err := context.Executor.ExecuteCommand(false, "", "lvchange", "-an", volumeGroupName); err != nil {
		return fmt.Errorf("failed to deactivate LVM %s. Error: %+v", volumeGroupName, err)
	}
	logger.Info("Successfully released device from lvm")
	return nil
}

//getVolumeGroupName returns the Volume group name from the given Logical Volume Path
func getVolumeGroupName(lvPath string) (string, error) {
	if lvPath == "" {
		return "", fmt.Errorf("empty LV Path : %s", lvPath)
	}

	vgSlice := strings.Split(lvPath, "/")
	//Assert that lvpath is in correct format `/dev/<vg name>/<lv name>` before extracting the vg name
	if len(vgSlice) != 4 || vgSlice[2] == "" {
		return "", fmt.Errorf("invalid LV Path : %s", lvPath)
	}

	return vgSlice[2], nil
}