feat: support sysfs.Mdraids with Intel VROC

blockdevice/stats_test.go

@@ -75,7 +75,7 @@ func TestBlockDevice(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	expectedNumOfDevices := 14
+	expectedNumOfDevices := 16
 	if len(devices) != expectedNumOfDevices {
 		t.Fatalf(failMsgFormat, "Incorrect number of devices", expectedNumOfDevices, len(devices))
 	}
@@ -95,18 +95,18 @@ func TestBlockDevice(t *testing.T) {
 	if device0stats.WeightedIOTicks != 6088971 {
 		t.Errorf(failMsgFormat, "Incorrect time in queue", 6088971, device0stats.WeightedIOTicks)
 	}
-	device9stats, count, err := blockdevice.SysBlockDeviceStat(devices[9])
+	device11stats, count, err := blockdevice.SysBlockDeviceStat(devices[11])
 	if count != 15 {
 		t.Errorf(failMsgFormat, "Incorrect number of stats read", 15, count)
 	}
 	if err != nil {
 		t.Fatal(err)
 	}
-	if device9stats.WriteSectors != 286915323 {
-		t.Errorf(failMsgFormat, "Incorrect write merges", 286915323, device9stats.WriteSectors)
+	if device11stats.WriteSectors != 286915323 {
+		t.Errorf(failMsgFormat, "Incorrect write merges", 286915323, device11stats.WriteSectors)
 	}
-	if device9stats.DiscardTicks != 12 {
-		t.Errorf(failMsgFormat, "Incorrect discard ticks", 12, device9stats.DiscardTicks)
+	if device11stats.DiscardTicks != 12 {
+		t.Errorf(failMsgFormat, "Incorrect discard ticks", 12, device11stats.DiscardTicks)
 	}
 	blockQueueStatExpected := BlockQueueStats{
 		AddRandom:            1,
@@ -147,7 +147,7 @@ func TestBlockDevice(t *testing.T) {
 		WriteZeroesMaxBytes:  0,
 	}
 
-	blockQueueStat, err := blockdevice.SysBlockDeviceQueueStats(devices[9])
+	blockQueueStat, err := blockdevice.SysBlockDeviceQueueStats(devices[11])
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -181,7 +181,7 @@ func TestBlockDmInfo(t *testing.T) {
 		t.Fatalf("unexpected BlockQueueStat (-want +got):\n%s", diff)
 	}
 
-	dm1Info, err := blockdevice.SysBlockDeviceMapperInfo(devices[9])
+	dm1Info, err := blockdevice.SysBlockDeviceMapperInfo(devices[11])
 	if err != nil {
 		var pErr *os.PathError
 		if errors.As(err, &pErr) {
@@ -232,13 +232,13 @@ func TestSysBlockDeviceSize(t *testing.T) {
 	if err != nil {
 		t.Fatal(err)
 	}
-	size9, err := blockdevice.SysBlockDeviceSize(devices[9])
+	size11, err := blockdevice.SysBlockDeviceSize(devices[11])
 	if err != nil {
 		t.Fatal(err)
 	}
-	size9Expected := uint64(1920383410176)
-	if size9 != size9Expected {
-		t.Errorf("Incorrect BlockDeviceSize, expected: \n%+v, got: \n%+v", size9Expected, size9)
+	size11Expected := uint64(1920383410176)
+	if size11 != size11Expected {
+		t.Errorf("Incorrect BlockDeviceSize, expected: \n%+v, got: \n%+v", size11Expected, size11)
 	}
 }
 
@@ -252,13 +252,13 @@ func TestSysBlockDeviceRotational(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	// devices[9] is "sda" in the fixtures — a rotational HDD (value: 1).
-	rotational9, err := blockdevice.SysBlockDeviceRotational(devices[9])
+	// devices[11] is "sda" in the fixtures — a rotational HDD (value: 1).
+	rotational11, err := blockdevice.SysBlockDeviceRotational(devices[11])
 	if err != nil {
 		t.Fatal(err)
 	}
-	if rotational9 != 1 {
-		t.Errorf("Incorrect rotational value for %s: expected 1, got %d", devices[9], rotational9)
+	if rotational11 != 1 {
+		t.Errorf("Incorrect rotational value for %s: expected 1, got %d", devices[11], rotational11)
 	}
 
 	// devices[0] is "dm-0" — no queue/rotational file; expect an error.

sysfs/mdraid.go

@@ -17,7 +17,9 @@ package sysfs
 
 import (
 	"fmt"
+	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 
 	"github.com/prometheus/procfs/internal/util"
@@ -26,10 +28,10 @@ import (
 // Mdraid holds info parsed from relevant files in the /sys/block/md*/md directory.
 type Mdraid struct {
 	Device          string            // Kernel device name of array.
-	Level           string            // mdraid level.
+	Level           string            // mdraid level. Empty if level file is unreadable.
 	ArrayState      string            // State of the array.
 	MetadataVersion string            // mdraid metadata version.
-	Disks           uint64            // Number of devices in a fully functional array.
+	Disks           *uint64           // Number of devices in a fully functional array. Nil when unavailable (e.g. container/imsm/ddf, empty level, or empty raid_disks).
 	Components      []MdraidComponent // mdraid component devices.
 	UUID            string            // UUID of the array.
 
@@ -81,10 +83,38 @@ func (fs FS) Mdraids() ([]Mdraid, error) {
 			return mdraids, err
 		}
 
-		if val, err := util.ReadUintFromFile(filepath.Join(path, "raid_disks")); err == nil {
-			md.Disks = val
-		} else {
-			return mdraids, err
+		// Parse raid_disks:
+		// - Container types (container/imsm/ddf) have no physical disks assigned.
+		// - Empty level file means we can't determine the array type, skip parsing.
+		// - During reshape/grow, raid_disks may contain "current (previous)" (e.g. "11 (10)").
+		// - Normal case is a plain integer.
+		switch md.Level {
+		case "container", "imsm", "ddf":
+			// No disks for container-type arrays, Disks remains nil.
+		case "":
+			// Empty level file, cannot determine disk count, Disks remains nil.
+		default:
+			data, err := os.ReadFile(filepath.Join(path, "raid_disks"))
+			if err != nil {
+				return mdraids, fmt.Errorf("reading raid_disks for %s: %w", md.Device, err)
+			}
+			content := strings.TrimSpace(string(data))
+			if content == "" {
+				// Empty file, Disks remains nil.
+				break
+			}
+
+			// Try normal integer parse first.
+			if val, parseErr := strconv.ParseUint(content, 10, 64); parseErr == nil {
+				md.Disks = &val
+			} else if idx := strings.Index(content, " "); idx > 0 {
+				// Reshape format: "current (previous)", extract the first number.
+				if val, parseErr := strconv.ParseUint(content[:idx], 10, 64); parseErr == nil {
+					md.Disks = &val
+				}
+				// If parsing fails, Disks remains nil (reshape in progress, count may be inaccurate).
+			}
+			// If neither format matches, Disks remains nil.
 		}
 
 		if val, err := util.SysReadFile(filepath.Join(path, "uuid")); err == nil {

sysfs/mdraid_test.go

@@ -32,13 +32,15 @@ func TestMdraidStats(t *testing.T) {
 		t.Fatal(err)
 	}
 
+	uint64ptr := func(v uint64) *uint64 { return &v }
+
 	want := []Mdraid{
 		{
 			Device:          "md0",
 			Level:           "raid0",
 			ArrayState:      "clean",
 			MetadataVersion: "1.2",
-			Disks:           2,
+			Disks:           uint64ptr(2),
 			Components: []MdraidComponent{
 				{Device: "sdg", State: "in_sync"},
 				{Device: "sdh", State: "in_sync"},
@@ -51,7 +53,7 @@ func TestMdraidStats(t *testing.T) {
 			Level:           "raid1",
 			ArrayState:      "clean",
 			MetadataVersion: "1.2",
-			Disks:           2,
+			Disks:           uint64ptr(2),
 			Components: []MdraidComponent{
 				{Device: "sdi", State: "in_sync"},
 				{Device: "sdj", State: "in_sync"},
@@ -64,7 +66,7 @@ func TestMdraidStats(t *testing.T) {
 			Level:           "raid10",
 			ArrayState:      "clean",
 			MetadataVersion: "1.2",
-			Disks:           4,
+			Disks:           uint64ptr(4),
 			Components: []MdraidComponent{
 				{Device: "sdu", State: "in_sync"},
 				{Device: "sdv", State: "in_sync"},
@@ -80,7 +82,7 @@ func TestMdraidStats(t *testing.T) {
 			Level:           "raid4",
 			ArrayState:      "clean",
 			MetadataVersion: "1.2",
-			Disks:           3,
+			Disks:           uint64ptr(3),
 			Components: []MdraidComponent{
 				{Device: "sdk", State: "in_sync"},
 				{Device: "sdl", State: "in_sync"},
@@ -95,7 +97,7 @@ func TestMdraidStats(t *testing.T) {
 			Level:           "raid5",
 			ArrayState:      "clean",
 			MetadataVersion: "1.2",
-			Disks:           3,
+			Disks:           uint64ptr(3),
 			Components: []MdraidComponent{
 				{Device: "sdaa", State: "spare"},
 				{Device: "sdn", State: "in_sync"},
@@ -112,7 +114,7 @@ func TestMdraidStats(t *testing.T) {
 			Level:           "raid6",
 			ArrayState:      "active",
 			MetadataVersion: "1.2",
-			Disks:           4,
+			Disks:           uint64ptr(4),
 			Components: []MdraidComponent{
 				{Device: "sdq", State: "in_sync"},
 				{Device: "sdr", State: "in_sync"},
@@ -125,6 +127,28 @@ func TestMdraidStats(t *testing.T) {
 			SyncAction:    "recover",
 			SyncCompleted: 0.7500458659491194,
 		},
+		{
+			Device:          "md7",
+			Level:           "container",
+			ArrayState:      "inactive",
+			MetadataVersion: "1.2",
+			Disks:           nil, // container type, no disks assigned
+			UUID:            "0e51f6d1-b357-2712-8eaa-31f6f597be6b",
+		},
+		{
+			Device:          "md8",
+			Level:           "raid5",
+			ArrayState:      "active",
+			MetadataVersion: "1.2",
+			Disks:           uint64ptr(11), // reshaping from 10 to 11, current value is 11
+			Components: []MdraidComponent{
+				{Device: "sdy", State: "in_sync"},
+				{Device: "sdz", State: "in_sync"},
+			},
+			UUID:       "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
+			ChunkSize:  524288,
+			SyncAction: "reshape",
+		},
 	}
 
 	if diff := cmp.Diff(want, got); diff != "" {