logical disk: Fix metrics for non drive letter disks (#1498)

pkg/collector/logical_disk/logical_disk.go

@@ -3,16 +3,18 @@
 package logical_disk
 
 import (
-	"errors"
+	"encoding/binary"
 	"fmt"
+	"golang.org/x/sys/windows"
 	"regexp"
+	"strconv"
+	"strings"
 
 	"github.com/alecthomas/kingpin/v2"
 	"github.com/go-kit/log"
 	"github.com/go-kit/log/level"
 	"github.com/prometheus-community/windows_exporter/pkg/perflib"
 	"github.com/prometheus-community/windows_exporter/pkg/types"
-	"github.com/prometheus-community/windows_exporter/pkg/wmi"
 	"github.com/prometheus/client_golang/prometheus"
 )
 
@@ -21,15 +23,8 @@ const (
 
 	FlagLogicalDiskVolumeExclude = "collector.logical_disk.volume-exclude"
 	FlagLogicalDiskVolumeInclude = "collector.logical_disk.volume-include"
-
-	win32DiskQuery = "SELECT VolumeName,DeviceID FROM WIN32_LogicalDisk"
 )
 
-type Win32_LogicalDisk struct {
-	VolumeName string
-	DeviceID   string
-}
-
 type Config struct {
 	VolumeInclude string `yaml:"volume_include"`
 	VolumeExclude string `yaml:"volume_exclude"`
@@ -47,6 +42,8 @@ type collector struct {
 	volumeInclude *string
 	volumeExclude *string
 
+	Information      *prometheus.Desc
+	ReadOnly         *prometheus.Desc
 	RequestsQueued   *prometheus.Desc
 	AvgReadQueue     *prometheus.Desc
 	AvgWriteQueue    *prometheus.Desc
@@ -68,6 +65,14 @@ type collector struct {
 	volumeExcludePattern *regexp.Regexp
 }
 
+type volumeInfo struct {
+	filesystem   string
+	serialNumber string
+	label        string
+	volumeType   string
+	readonly     float64
+}
+
 func New(logger log.Logger, config *Config) types.Collector {
 	if config == nil {
 		config = &ConfigDefaults
@@ -109,115 +114,127 @@ func (c *collector) GetPerfCounter() ([]string, error) {
 }
 
 func (c *collector) Build() error {
+	c.Information = prometheus.NewDesc(
+		prometheus.BuildFQName(types.Namespace, Name, "info"),
+		"A metric with a constant '1' value labeled with logical disk information",
+		[]string{"disk", "type", "volume", "volume_name", "filesystem", "serial_number"},
+		nil,
+	)
+	c.ReadOnly = prometheus.NewDesc(
+		prometheus.BuildFQName(types.Namespace, Name, "readonly"),
+		"Whether the logical disk is read-only",
+		[]string{"volume"},
+		nil,
+	)
 	c.RequestsQueued = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "requests_queued"),
 		"The number of requests queued to the disk (LogicalDisk.CurrentDiskQueueLength)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.AvgReadQueue = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "avg_read_requests_queued"),
 		"Average number of read requests that were queued for the selected disk during the sample interval (LogicalDisk.AvgDiskReadQueueLength)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.AvgWriteQueue = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "avg_write_requests_queued"),
 		"Average number of write requests that were queued for the selected disk during the sample interval (LogicalDisk.AvgDiskWriteQueueLength)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.ReadBytesTotal = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "read_bytes_total"),
 		"The number of bytes transferred from the disk during read operations (LogicalDisk.DiskReadBytesPerSec)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.ReadsTotal = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "reads_total"),
 		"The number of read operations on the disk (LogicalDisk.DiskReadsPerSec)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.WriteBytesTotal = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "write_bytes_total"),
 		"The number of bytes transferred to the disk during write operations (LogicalDisk.DiskWriteBytesPerSec)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.WritesTotal = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "writes_total"),
 		"The number of write operations on the disk (LogicalDisk.DiskWritesPerSec)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.ReadTime = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "read_seconds_total"),
 		"Seconds that the disk was busy servicing read requests (LogicalDisk.PercentDiskReadTime)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.WriteTime = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "write_seconds_total"),
 		"Seconds that the disk was busy servicing write requests (LogicalDisk.PercentDiskWriteTime)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.FreeSpace = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "free_bytes"),
 		"Free space in bytes, updates every 10-15 min (LogicalDisk.PercentFreeSpace)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.TotalSpace = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "size_bytes"),
 		"Total space in bytes, updates every 10-15 min (LogicalDisk.PercentFreeSpace_Base)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.IdleTime = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "idle_seconds_total"),
 		"Seconds that the disk was idle (LogicalDisk.PercentIdleTime)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.SplitIOs = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "split_ios_total"),
 		"The number of I/Os to the disk were split into multiple I/Os (LogicalDisk.SplitIOPerSec)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.ReadLatency = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "read_latency_seconds_total"),
 		"Shows the average time, in seconds, of a read operation from the disk (LogicalDisk.AvgDiskSecPerRead)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.WriteLatency = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "write_latency_seconds_total"),
 		"Shows the average time, in seconds, of a write operation to the disk (LogicalDisk.AvgDiskSecPerWrite)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
 	c.ReadWriteLatency = prometheus.NewDesc(
 		prometheus.BuildFQName(types.Namespace, Name, "read_write_latency_seconds_total"),
 		"Shows the time, in seconds, of the average disk transfer (LogicalDisk.AvgDiskSecPerTransfer)",
-		[]string{"volume", "volume_name"},
+		[]string{"volume"},
 		nil,
 	)
 
@@ -250,7 +267,6 @@ func (c *collector) Collect(ctx *types.ScrapeContext, ch chan<- prometheus.Metri
 // - https://msdn.microsoft.com/en-us/library/ms803973.aspx - LogicalDisk object reference
 type logicalDisk struct {
 	Name                    string
-	VolumeName              string
 	CurrentDiskQueueLength  float64 `perflib:"Current Disk Queue Length"`
 	AvgDiskReadQueueLength  float64 `perflib:"Avg. Disk Read Queue Length"`
 	AvgDiskWriteQueueLength float64 `perflib:"Avg. Disk Write Queue Length"`
@@ -270,17 +286,14 @@ type logicalDisk struct {
 }
 
 func (c *collector) collect(ctx *types.ScrapeContext, ch chan<- prometheus.Metric) error {
-	var dst_Win32_LogicalDisk []Win32_LogicalDisk
+	var (
+		err    error
+		diskID string
+		info   volumeInfo
+		dst    []logicalDisk
+	)
 
-	if err := wmi.Query(win32DiskQuery, &dst_Win32_LogicalDisk); err != nil {
-		return err
-	}
-	if len(dst_Win32_LogicalDisk) == 0 {
-		return errors.New("WMI query returned empty result set")
-	}
-
-	var dst []logicalDisk
-	if err := perflib.UnmarshalObject(ctx.PerfObjects["LogicalDisk"], &dst, c.logger); err != nil {
+	if err = perflib.UnmarshalObject(ctx.PerfObjects["LogicalDisk"], &dst, c.logger); err != nil {
 		return err
 	}
 
@@ -290,145 +303,233 @@ func (c *collector) collect(ctx *types.ScrapeContext, ch chan<- prometheus.Metri
 			!c.volumeIncludePattern.MatchString(volume.Name) {
 			continue
 		}
-		for _, logicalDisk := range dst_Win32_LogicalDisk {
-			if logicalDisk.VolumeName == "" {
-				logicalDisk.VolumeName = "Local Disk"
-			}
-			if logicalDisk.DeviceID == volume.Name {
-				ch <- prometheus.MustNewConstMetric(
-					c.RequestsQueued,
-					prometheus.GaugeValue,
-					volume.CurrentDiskQueueLength,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
 
-				ch <- prometheus.MustNewConstMetric(
-					c.AvgReadQueue,
-					prometheus.GaugeValue,
-					volume.AvgDiskReadQueueLength*perflib.TicksToSecondScaleFactor,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.AvgWriteQueue,
-					prometheus.GaugeValue,
-					volume.AvgDiskWriteQueueLength*perflib.TicksToSecondScaleFactor,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.ReadBytesTotal,
-					prometheus.CounterValue,
-					volume.DiskReadBytesPerSec,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.ReadsTotal,
-					prometheus.CounterValue,
-					volume.DiskReadsPerSec,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.WriteBytesTotal,
-					prometheus.CounterValue,
-					volume.DiskWriteBytesPerSec,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.WritesTotal,
-					prometheus.CounterValue,
-					volume.DiskWritesPerSec,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.ReadTime,
-					prometheus.CounterValue,
-					volume.PercentDiskReadTime,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.WriteTime,
-					prometheus.CounterValue,
-					volume.PercentDiskWriteTime,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.FreeSpace,
-					prometheus.GaugeValue,
-					volume.PercentFreeSpace_Base*1024*1024,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.TotalSpace,
-					prometheus.GaugeValue,
-					volume.PercentFreeSpace*1024*1024,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.IdleTime,
-					prometheus.CounterValue,
-					volume.PercentIdleTime,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.SplitIOs,
-					prometheus.CounterValue,
-					volume.SplitIOPerSec,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.ReadLatency,
-					prometheus.CounterValue,
-					volume.AvgDiskSecPerRead*perflib.TicksToSecondScaleFactor,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.WriteLatency,
-					prometheus.CounterValue,
-					volume.AvgDiskSecPerWrite*perflib.TicksToSecondScaleFactor,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				ch <- prometheus.MustNewConstMetric(
-					c.ReadWriteLatency,
-					prometheus.CounterValue,
-					volume.AvgDiskSecPerTransfer*perflib.TicksToSecondScaleFactor,
-					volume.Name,
-					logicalDisk.VolumeName,
-				)
-
-				break
-
-			}
+		diskID, err = getDiskIDByVolume(volume.Name)
+		if err != nil {
+			_ = level.Warn(c.logger).Log("msg", "failed to get disk ID for "+volume.Name, "err", err)
 		}
 
+		info, err = getVolumeInfo(volume.Name)
+		if err != nil {
+			_ = level.Warn(c.logger).Log("msg", "failed to get volume information for %s"+volume.Name, "err", err)
+		}
+
+		ch <- prometheus.MustNewConstMetric(
+			c.Information,
+			prometheus.GaugeValue,
+			1,
+			diskID,
+			info.volumeType,
+			volume.Name,
+			info.label,
+			info.filesystem,
+			info.serialNumber,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.RequestsQueued,
+			prometheus.GaugeValue,
+			volume.CurrentDiskQueueLength,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.AvgReadQueue,
+			prometheus.GaugeValue,
+			volume.AvgDiskReadQueueLength*perflib.TicksToSecondScaleFactor,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.AvgWriteQueue,
+			prometheus.GaugeValue,
+			volume.AvgDiskWriteQueueLength*perflib.TicksToSecondScaleFactor,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.ReadBytesTotal,
+			prometheus.CounterValue,
+			volume.DiskReadBytesPerSec,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.ReadsTotal,
+			prometheus.CounterValue,
+			volume.DiskReadsPerSec,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.WriteBytesTotal,
+			prometheus.CounterValue,
+			volume.DiskWriteBytesPerSec,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.WritesTotal,
+			prometheus.CounterValue,
+			volume.DiskWritesPerSec,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.ReadTime,
+			prometheus.CounterValue,
+			volume.PercentDiskReadTime,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.WriteTime,
+			prometheus.CounterValue,
+			volume.PercentDiskWriteTime,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.FreeSpace,
+			prometheus.GaugeValue,
+			volume.PercentFreeSpace_Base*1024*1024,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.TotalSpace,
+			prometheus.GaugeValue,
+			volume.PercentFreeSpace*1024*1024,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.IdleTime,
+			prometheus.CounterValue,
+			volume.PercentIdleTime,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.SplitIOs,
+			prometheus.CounterValue,
+			volume.SplitIOPerSec,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.ReadLatency,
+			prometheus.CounterValue,
+			volume.AvgDiskSecPerRead*perflib.TicksToSecondScaleFactor,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.WriteLatency,
+			prometheus.CounterValue,
+			volume.AvgDiskSecPerWrite*perflib.TicksToSecondScaleFactor,
+			volume.Name,
+		)
+
+		ch <- prometheus.MustNewConstMetric(
+			c.ReadWriteLatency,
+			prometheus.CounterValue,
+			volume.AvgDiskSecPerTransfer*perflib.TicksToSecondScaleFactor,
+			volume.Name,
+		)
 	}
 
 	return nil
 }
+
+func getDriveType(driveType uint32) string {
+	switch driveType {
+	case windows.DRIVE_UNKNOWN:
+		return "unknown"
+	case windows.DRIVE_NO_ROOT_DIR:
+		return "norootdir"
+	case windows.DRIVE_REMOVABLE:
+		return "removable"
+	case windows.DRIVE_FIXED:
+		return "fixed"
+	case windows.DRIVE_REMOTE:
+		return "remote"
+	case windows.DRIVE_CDROM:
+		return "cdrom"
+	case windows.DRIVE_RAMDISK:
+		return "ramdisk"
+	default:
+		return "unknown"
+	}
+}
+
+// getDiskIDByVolume returns the disk ID for a given volume.
+func getDiskIDByVolume(rootDrive string) (string, error) {
+	// Open a volume handle to the Disk Root.
+	var err error
+	var f windows.Handle
+
+	// mode has to include FILE_SHARE permission to allow concurrent access to the disk.
+	// use 0 as access mode to avoid admin permission.
+	mode := uint32(windows.FILE_SHARE_READ | windows.FILE_SHARE_WRITE | windows.FILE_SHARE_DELETE)
+	f, err = windows.CreateFile(
+		windows.StringToUTF16Ptr(`\\.\`+rootDrive),
+		0, mode, nil, windows.OPEN_EXISTING, uint32(windows.FILE_ATTRIBUTE_READONLY), 0)
+
+	if err != nil {
+		return "", err
+	}
+
+	defer windows.Close(f)
+
+	controlCode := uint32(5636096) // IOCTL_VOLUME_GET_VOLUME_DISK_EXTENTS
+	volumeDiskExtents := make([]byte, 16*1024)
+
+	var bytesReturned uint32
+	err = windows.DeviceIoControl(f, controlCode, nil, 0, &volumeDiskExtents[0], uint32(len(volumeDiskExtents)), &bytesReturned, nil)
+	if err != nil {
+		return "", err
+	}
+
+	if uint(binary.LittleEndian.Uint32(volumeDiskExtents)) != 1 {
+		return "", fmt.Errorf("could not identify physical drive for %s", rootDrive)
+	}
+
+	diskId := strconv.FormatUint(uint64(binary.LittleEndian.Uint32(volumeDiskExtents[8:])), 10)
+
+	return diskId, nil
+}
+
+func getVolumeInfo(rootDrive string) (volumeInfo, error) {
+	if !strings.HasSuffix(rootDrive, ":") {
+		return volumeInfo{}, nil
+	}
+
+	volPath := windows.StringToUTF16Ptr(rootDrive + `\`)
+
+	volBufLabel := make([]uint16, windows.MAX_PATH+1)
+	volSerialNum := uint32(0)
+	fsFlags := uint32(0)
+	volBufType := make([]uint16, windows.MAX_PATH+1)
+
+	driveType := windows.GetDriveType(volPath)
+
+	err := windows.GetVolumeInformation(volPath, &volBufLabel[0], uint32(len(volBufLabel)),
+		&volSerialNum, nil, &fsFlags, &volBufType[0], uint32(len(volBufType)))
+
+	if err != nil {
+		if driveType != windows.DRIVE_CDROM && driveType != windows.DRIVE_REMOVABLE {
+			return volumeInfo{}, err
+		}
+
+		return volumeInfo{}, nil
+	}
+
+	return volumeInfo{
+		volumeType:   getDriveType(driveType),
+		label:        windows.UTF16PtrToString(&volBufLabel[0]),
+		filesystem:   windows.UTF16PtrToString(&volBufType[0]),
+		serialNumber: fmt.Sprintf("%X", volSerialNum),
+		readonly:     float64(fsFlags & windows.FILE_READ_ONLY_VOLUME),
+	}, nil
+}