Added the device revision support for linux and fixed NUMANodeID read process

README.md

@@ -511,6 +511,7 @@ Each `ghw.Disk` struct contains the following fields:
   [World Wide Name](https://en.wikipedia.org/wiki/World_Wide_Name)
 * `ghw.Disk.Partitions` contains an array of pointers to `ghw.Partition`
   structs, one for each partition on the disk
+  `ghw.Disk.Revision` contains a string with the disk's device revision 
 
 Each `ghw.Partition` struct contains these fields:
 

pkg/block/block.go

@@ -106,6 +106,7 @@ type Disk struct {
 	SerialNumber string       `json:"serial_number"`
 	WWN          string       `json:"wwn"`
 	Partitions   []*Partition `json:"partitions"`
+	Revision     string       `json:"revision"`
 	// TODO(jaypipes): Add PCI field for accessing PCI device information
 	// PCI *PCIDevice `json:"pci"`
 }
@@ -190,8 +191,12 @@ func (d *Disk) String() string {
 	if d.IsRemovable {
 		removable = " removable=true"
 	}
+	revision := ""
+	if d.Revision != "" {
+		revision = " revision=" + d.Revision
+	}
 	return fmt.Sprintf(
-		"%s %s (%s) %s [@%s%s]%s%s%s%s%s",
+		"%s %s (%s) %s [@%s%s]%s%s%s%s%s%s",
 		d.Name,
 		d.DriveType.String(),
 		sizeStr,
@@ -203,6 +208,7 @@ func (d *Disk) String() string {
 		serial,
 		wwn,
 		removable,
+		revision,
 	)
 }
 

pkg/block/block_linux.go

@@ -71,8 +71,8 @@ func diskNUMANodeID(paths *linuxpath.Paths, disk string) int {
 		return -1
 	}
 	for partial := link; strings.HasPrefix(partial, "../devices/"); partial = filepath.Base(partial) {
-		if nodeContents, err := ioutil.ReadFile(filepath.Join(paths.SysBlock, partial, "numa_node")); err != nil {
-			if nodeInt, err := strconv.Atoi(string(nodeContents)); err != nil {
+		if nodeContents, err := ioutil.ReadFile(filepath.Join(paths.SysBlock, partial, "numa_node")); err == nil {
+			if nodeInt, err := strconv.Atoi(string(nodeContents)); err == nil {
 				return nodeInt
 			}
 		}
@@ -91,6 +91,17 @@ func diskVendor(paths *linuxpath.Paths, disk string) string {
 	return strings.TrimSpace(string(contents))
 }
 
+func diskRevision(paths *linuxpath.Paths, disk string) string {
+	// In Linux, the disk revision is found in the
+	// /sys/block/$DEVICE/device/rev file in sysfs
+	path := filepath.Join(paths.SysBlock, disk, "device", "rev")
+	contents, err := ioutil.ReadFile(path)
+	if err != nil {
+		return util.UNKNOWN
+	}
+	return strings.TrimSpace(string(contents))
+}
+
 func udevInfo(paths *linuxpath.Paths, disk string) (map[string]string, error) {
 	// Get device major:minor numbers
 	devNo, err := ioutil.ReadFile(filepath.Join(paths.SysBlock, disk, "dev"))
@@ -286,6 +297,7 @@ func disks(ctx *context.Context, paths *linuxpath.Paths) []*Disk {
 		serialNo := diskSerialNumber(paths, dname)
 		wwn := diskWWN(paths, dname)
 		removable := diskIsRemovable(paths, dname)
+		revision := diskRevision(paths, dname)
 
 		d := &Disk{
 			Name:                   dname,
@@ -300,6 +312,7 @@ func disks(ctx *context.Context, paths *linuxpath.Paths) []*Disk {
 			Model:                  model,
 			SerialNumber:           serialNo,
 			WWN:                    wwn,
+			Revision:               revision,
 		}
 
 		parts := diskPartitions(ctx, paths, dname)