func deviceMountDisk(srcPath string, dstPath string, readonly bool) error {
var err error
// Prepare the mount flags
flags := 0
if readonly {
flags |= syscall.MS_RDONLY
}
// Detect the filesystem
fstype := "none"
if deviceIsDevice(srcPath) {
fstype, err = shared.BlockFsDetect(srcPath)
if err != nil {
return err
}
} else {
flags |= syscall.MS_BIND
}
// Mount the filesystem
if err = syscall.Mount(srcPath, dstPath, fstype, uintptr(flags), ""); err != nil {
return fmt.Errorf("Unable to mount %s at %s: %s", srcPath, dstPath, err)
}
return nil
}
func deviceToLxc(d shared.Device) ([][]string, error) {
switch d["type"] {
case "unix-char":
return nil, fmt.Errorf("Not implemented")
case "unix-block":
return nil, fmt.Errorf("Not implemented")
case "nic":
if d["nictype"] != "bridged" && d["nictype"] != "" {
return nil, fmt.Errorf("Bad nic type: %s\n", d["nictype"])
}
var l1 = []string{"lxc.network.type", "veth"}
var lines = [][]string{l1}
var l2 []string
if d["hwaddr"] != "" {
l2 = []string{"lxc.network.hwaddr", d["hwaddr"]}
lines = append(lines, l2)
}
if d["mtu"] != "" {
l2 = []string{"lxc.network.mtu", d["mtu"]}
lines = append(lines, l2)
}
if d["parent"] != "" {
l2 = []string{"lxc.network.link", d["parent"]}
lines = append(lines, l2)
}
if d["name"] != "" {
l2 = []string{"lxc.network.name", d["name"]}
lines = append(lines, l2)
}
return lines, nil
case "disk":
var p string
configLines := [][]string{}
if d["path"] == "/" || d["path"] == "" {
p = ""
} else if d["path"][0:1] == "/" {
p = d["path"][1:]
} else {
p = d["path"]
}
/* TODO - check whether source is a disk, loopback, btrfs subvol, etc */
/* for now we only handle directory bind mounts */
source := d["source"]
fstype := "none"
options := []string{}
var err error
if shared.IsBlockdevPath(d["source"]) {
fstype, err = shared.BlockFsDetect(d["source"])
if err != nil {
return nil, fmt.Errorf("Error setting up %s: %s\n", d["name"], err)
}
l, err := addBlockDev(d["source"])
if err != nil {
return nil, fmt.Errorf("Error adding blockdev: %s\n", err)
}
configLines = append(configLines, l)
} else if shared.IsDir(source) {
options = append(options, "bind")
options = append(options, "create=dir")
} else /* file bind mount */ {
/* Todo - can we distinguish between file bind mount and
* a qcow2 (or other fs container) file? */
options = append(options, "bind")
options = append(options, "create=file")
}
if d["readonly"] == "1" || d["readonly"] == "true" {
options = append(options, "ro")
}
if d["optional"] == "1" || d["optional"] == "true" {
options = append(options, "optional")
}
opts := strings.Join(options, ",")
if opts == "" {
opts = "defaults"
}
l := []string{"lxc.mount.entry", fmt.Sprintf("%s %s %s %s 0 0", source, p, fstype, opts)}
configLines = append(configLines, l)
return configLines, nil
case "none":
return nil, nil
default:
return nil, fmt.Errorf("Bad device type")
}
}
func (c *containerLXD) AttachMount(m shared.Device) error {
dest := m["path"]
source := m["source"]
opts := ""
fstype := "none"
flags := 0
sb, err := os.Stat(source)
if err != nil {
return err
}
if sb.IsDir() {
flags |= syscall.MS_BIND
opts = "bind,create=dir"
} else {
if !shared.IsBlockdev(sb.Mode()) {
// Not sure if we want to try dealing with loopdevs, but
// since we'd need to deal with partitions i think not.
// We also might want to support file bind mounting, but
// this doesn't do that.
return fmt.Errorf("non-block device file not supported\n")
}
fstype, err = shared.BlockFsDetect(source)
if err != nil {
return fmt.Errorf("Unable to detect fstype for %s: %s\n", source, err)
}
}
// add a lxc.mount.entry = souce destination, in case of reboot
if m["readonly"] == "1" || m["readonly"] == "true" {
if opts == "" {
opts = "ro"
} else {
opts = opts + ",ro"
}
}
optional := false
if m["optional"] == "1" || m["optional"] == "true" {
optional = true
opts = opts + ",optional"
}
entry := fmt.Sprintf("%s %s %s %s 0 0", source, dest, fstype, opts)
if err := c.c.SetConfigItem("lxc.mount.entry", entry); err != nil {
return err
}
pid := c.c.InitPid()
if pid == -1 { // container not running - we're done
return nil
}
// now live-mount
tmpMount, err := ioutil.TempDir(shared.VarPath("shmounts", c.name), "lxdmount_")
if err != nil {
return err
}
err = syscall.Mount(m["source"], tmpMount, fstype, uintptr(flags), "")
if err != nil {
return err
}
mntsrc := filepath.Join("/.lxdmounts", filepath.Base(tmpMount))
// finally we need to move-mount this in the container
pidstr := fmt.Sprintf("%d", pid)
err = exec.Command(os.Args[0], "forkmount", pidstr, mntsrc, m["path"]).Run()
syscall.Unmount(tmpMount, syscall.MNT_DETACH) // in case forkmount failed
os.Remove(tmpMount)
if err != nil && !optional {
return err
}
return nil
}