Use `blkid` to get fs type of device.

`lsblk` reads fs type info from udev files. If udev rules are not
installed. `lsblk` could not get correct fs type. This will cause
problems, e.g. expanding volume depends on fs type of disk.

pkg/util/mount/mount_linux.go

@@ -536,11 +536,11 @@ func (mounter *SafeFormatAndMount) formatAndMount(source string, target string,
 	return mountErr
 }
 
-// GetDiskFormat uses 'lsblk' to see if the given disk is unformated
+// GetDiskFormat uses 'blkid' to see if the given disk is unformated
 func (mounter *SafeFormatAndMount) GetDiskFormat(disk string) (string, error) {
-	args := []string{"-n", "-o", "FSTYPE", disk}
+	args := []string{"-p", "-s", "TYPE", "-o", "value", disk}
-	glog.V(4).Infof("Attempting to determine if disk %q is formatted using lsblk with args: (%v)", disk, args)
+	glog.V(4).Infof("Attempting to determine if disk %q is formatted using blkid with args: (%v)", disk, args)
-	dataOut, err := mounter.Exec.Run("lsblk", args...)
+	dataOut, err := mounter.Exec.Run("blkid", args...)
 	output := string(dataOut)
 	glog.V(4).Infof("Output: %q", output)
 
@@ -549,23 +549,12 @@ func (mounter *SafeFormatAndMount) GetDiskFormat(disk string) (string, error) {
 		return "", err
 	}
 
-	// Split lsblk output into lines. Unformatted devices should contain only
+	if len(output) <= 0 {
-	// "\n". Beware of "\n\n", that's a device with one empty partition.
+		// no fs type
-	output = strings.TrimSuffix(output, "\n") // Avoid last empty line
-	lines := strings.Split(output, "\n")
-	if lines[0] != "" {
-		// The device is formatted
-		return lines[0], nil
-	}
-
-	if len(lines) == 1 {
-		// The device is unformatted and has no dependent devices
 		return "", nil
 	}
 
-	// The device has dependent devices, most probably partitions (LVM, LUKS
+	return strings.TrimSpace(output), nil
-	// and MD RAID are reported as FSTYPE and caught above).
-	return "unknown data, probably partitions", nil
 }
 
 // isShared returns true, if given path is on a mount point that has shared

pkg/util/mount/safe_format_and_mount_test.go

@@ -100,55 +100,55 @@ func TestSafeFormatAndMount(t *testing.T) {
 			},
 		},
 		{
-			description: "Test that 'lsblk' is called and fails",
+			description: "Test that 'blkid' is called and fails",
 			fstype:      "ext4",
 			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'")},
 			execScripts: []ExecArgs{
 				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
-				{"lsblk", []string{"-n", "-o", "FSTYPE", "/dev/foo"}, "ext4\n", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-o", "value", "/dev/foo"}, "ext4\n", nil},
 			},
 			expectedError: fmt.Errorf("unknown filesystem type '(null)'"),
 		},
 		{
-			description: "Test that 'lsblk' is called and confirms unformatted disk, format fails",
+			description: "Test that 'blkid' is called and confirms unformatted disk, format fails",
 			fstype:      "ext4",
 			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'")},
 			execScripts: []ExecArgs{
 				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
-				{"lsblk", []string{"-n", "-o", "FSTYPE", "/dev/foo"}, "\n", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-o", "value", "/dev/foo"}, "", nil},
 				{"mkfs.ext4", []string{"-F", "/dev/foo"}, "", fmt.Errorf("formatting failed")},
 			},
 			expectedError: fmt.Errorf("formatting failed"),
 		},
 		{
-			description: "Test that 'lsblk' is called and confirms unformatted disk, format passes, second mount fails",
+			description: "Test that 'blkid' is called and confirms unformatted disk, format passes, second mount fails",
 			fstype:      "ext4",
 			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'"), fmt.Errorf("Still cannot mount")},
 			execScripts: []ExecArgs{
 				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
-				{"lsblk", []string{"-n", "-o", "FSTYPE", "/dev/foo"}, "\n", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-o", "value", "/dev/foo"}, "", nil},
 				{"mkfs.ext4", []string{"-F", "/dev/foo"}, "", nil},
 			},
 			expectedError: fmt.Errorf("Still cannot mount"),
 		},
 		{
-			description: "Test that 'lsblk' is called and confirms unformatted disk, format passes, second mount passes",
+			description: "Test that 'blkid' is called and confirms unformatted disk, format passes, second mount passes",
 			fstype:      "ext4",
 			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'"), nil},
 			execScripts: []ExecArgs{
 				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
-				{"lsblk", []string{"-n", "-o", "FSTYPE", "/dev/foo"}, "\n", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-o", "value", "/dev/foo"}, "", nil},
 				{"mkfs.ext4", []string{"-F", "/dev/foo"}, "", nil},
 			},
 			expectedError: nil,
 		},
 		{
-			description: "Test that 'lsblk' is called and confirms unformatted disk, format passes, second mount passes with ext3",
+			description: "Test that 'blkid' is called and confirms unformatted disk, format passes, second mount passes with ext3",
 			fstype:      "ext3",
 			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'"), nil},
 			execScripts: []ExecArgs{
 				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
-				{"lsblk", []string{"-n", "-o", "FSTYPE", "/dev/foo"}, "\n", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-o", "value", "/dev/foo"}, "", nil},
 				{"mkfs.ext3", []string{"-F", "/dev/foo"}, "", nil},
 			},
 			expectedError: nil,
@@ -159,30 +159,20 @@ func TestSafeFormatAndMount(t *testing.T) {
 			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'"), nil},
 			execScripts: []ExecArgs{
 				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
-				{"lsblk", []string{"-n", "-o", "FSTYPE", "/dev/foo"}, "\n", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-o", "value", "/dev/foo"}, "", nil},
 				{"mkfs.xfs", []string{"/dev/foo"}, "", nil},
 			},
 			expectedError: nil,
 		},
 		{
-			description: "Test that 'lsblk' is called and reports ext4 partition",
+			description: "Test that 'blkid' is called and reports ext4 partition",
 			fstype:      "ext3",
 			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'")},
 			execScripts: []ExecArgs{
 				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
-				{"lsblk", []string{"-n", "-o", "FSTYPE", "/dev/foo"}, "\next4\n", nil},
+				{"blkid", []string{"-p", "-s", "TYPE", "-o", "value", "/dev/foo"}, "LVM2_member\n", nil},
 			},
-			expectedError: fmt.Errorf("failed to mount the volume as \"ext3\", it already contains unknown data, probably partitions. Mount error: unknown filesystem type '(null)'"),
+			expectedError: fmt.Errorf("failed to mount the volume as \"ext3\", it already contains LVM2_member. Mount error: unknown filesystem type '(null)'"),
-		},
-		{
-			description: "Test that 'lsblk' is called and reports empty partition",
-			fstype:      "ext3",
-			mountErrs:   []error{fmt.Errorf("unknown filesystem type '(null)'")},
-			execScripts: []ExecArgs{
-				{"fsck", []string{"-a", "/dev/foo"}, "", nil},
-				{"lsblk", []string{"-n", "-o", "FSTYPE", "/dev/foo"}, "\n\n", nil},
-			},
-			expectedError: fmt.Errorf("failed to mount the volume as \"ext3\", it already contains unknown data, probably partitions. Mount error: unknown filesystem type '(null)'"),
 		},
 	}