Initial commit

cmd/dkl-system-init/lvm.go

@@ -0,0 +1,157 @@
+package main
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"time"
+
+	"novit.nc/direktil/pkg/config"
+	"novit.nc/direktil/pkg/log"
+)
+
+const (
+	pDevName = "DEVNAME="
+)
+
+func init() {
+	go services.WaitPath("/run/lvm/lvmetad.socket")
+
+	services.Register(
+		&CommandService{
+			Name:    "lvmetad",
+			Restart: StdRestart,
+			Needs:   []string{"service:devfs"},
+			Command: []string{"lvmetad", "-f"},
+			PreExec: func() error {
+				mkdir("/run/lvm", 0700)
+				mkdir("/run/lock/lvm", 0700)
+
+				if !dmInProc() {
+					run("modprobe", "dm-mod")
+				}
+
+				return nil
+			},
+		},
+		&CommandService{
+			Name:  "lvm",
+			Needs: []string{"file:/run/lvm/lvmetad.socket"},
+			Command: []string{"/bin/sh", "-c", `set -ex
+/sbin/lvm pvscan
+/sbin/lvm vgscan --mknodes
+/sbin/lvm vgchange --sysinit -a ly
+`},
+		},
+	)
+}
+
+func isDir(path string) bool {
+	s, err := os.Stat(path)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return false
+		}
+		fatal("failed to query ", path, ": ", err)
+	}
+
+	return s.IsDir()
+}
+
+func dmInProc() bool {
+	for _, f := range []string{"devices", "misc"} {
+		c, err := ioutil.ReadFile("/proc/" + f)
+		if err != nil {
+			fatalf("failed to read %s: %v", f, err)
+		}
+		if !bytes.Contains(c, []byte("device-mapper")) {
+			return false
+		}
+	}
+	return true
+}
+
+func setupVG(udevMatch string) {
+	dev := ""
+	try := 0
+
+retry:
+	paths, err := filepath.Glob("/sys/class/block/*")
+	if err != nil {
+		fatal("failed to list block devices: ", err)
+	}
+
+	for _, path := range paths {
+		// ignore loop devices
+		if strings.HasPrefix("loop", filepath.Base(path)) {
+			continue
+		}
+
+		// fetch udev informations
+		out, err := exec.Command("udevadm", "info", "-q", "property", path).CombinedOutput()
+		if err != nil {
+			initLog.Taintf(log.Warning, "udev query of %q failed: %v\n%s", path, err, string(out))
+			continue
+		}
+
+		propertyLines := strings.Split(strings.TrimSpace(string(out)), "\n")
+
+		devPath := ""
+		matches := false
+
+		for _, line := range propertyLines {
+			if strings.HasPrefix(line, pDevName) {
+				devPath = line[len(pDevName):]
+			}
+
+			if line == udevMatch {
+				matches = true
+			}
+
+			if devPath != "" && matches {
+				break
+			}
+		}
+
+		if devPath != "" && matches {
+			dev = devPath
+			break
+		}
+	}
+
+	if dev == "" {
+		time.Sleep(1 * time.Second)
+		try++
+		if try > 30 {
+			fatal("storage device not found after 30s, failing.")
+		}
+		goto retry
+	}
+
+	initLog.Taint(log.Info, "found storage device at ", dev)
+
+	run("pvcreate", dev)
+	run("vgcreate", "storage", dev)
+}
+
+func setupLV(volume config.VolumeDef) {
+	if volume.Extents != "" {
+		run("lvcreate", "-l", volume.Extents, "-n", volume.Name, "storage")
+	} else {
+		run("lvcreate", "-L", volume.Size, "-n", volume.Name, "storage")
+	}
+
+	args := make([]string, 0)
+
+	switch volume.FS {
+	case "btrfs":
+		args = append(args, "-f")
+	case "ext4":
+		args = append(args, "-F")
+	}
+
+	run("mkfs."+volume.FS, append(args, "/dev/storage/"+volume.Name)...)
+}