[disk]linux: implements 'all' argument.

disk/disk_linux.go

@@ -211,7 +211,10 @@ var fsTypeMap = map[int64]string{
 	ZFS_SUPER_MAGIC:             "zfs",                 /* 0x2FC12FC1 local */
 }
 
-// Get disk partitions.
+// Partitions returns disk partitions. If all is false, returns
+// physical devices only (e.g. hard disks, cd-rom drives, USB keys)
+// and ignore all others (e.g. memory partitions such as /dev/shm)
+//
 // should use setmntent(3) but this implement use /etc/mtab file
 func Partitions(all bool) ([]PartitionStat, error) {
 	filename := common.HostEtc("mtab")
@@ -220,6 +223,11 @@ func Partitions(all bool) ([]PartitionStat, error) {
 		return nil, err
 	}
 
+	fs, err := getFileSystems()
+	if err != nil {
+		return nil, err
+	}
+
 	ret := make([]PartitionStat, 0, len(lines))
 
 	for _, line := range lines {
@@ -230,12 +238,40 @@ func Partitions(all bool) ([]PartitionStat, error) {
 			Fstype:     fields[2],
 			Opts:       fields[3],
 		}
+		if all == false {
+			if d.Device == "none" || !common.StringsHas(fs, d.Fstype) {
+				continue
+			}
+		}
 		ret = append(ret, d)
 	}
 
 	return ret, nil
 }
 
+// getFileSystems returns supported filesystems from /proc/filesystems
+func getFileSystems() ([]string, error) {
+	filename := common.HostProc("filesystems")
+	lines, err := common.ReadLines(filename)
+	if err != nil {
+		return nil, err
+	}
+	var ret []string
+	for _, line := range lines {
+		if !strings.HasPrefix(line, "nodev") {
+			ret = append(ret, strings.TrimSpace(line))
+			continue
+		}
+		t := strings.Split(line, "\t")
+		if len(t) != 2 || t[1] != "zfs" {
+			continue
+		}
+		ret = append(ret, strings.TrimSpace(t[1]))
+	}
+
+	return ret, nil
+}
+
 func IOCounters() (map[string]IOCountersStat, error) {
 	filename := common.HostProc("diskstats")
 	lines, err := common.ReadLines(filename)