Example #1
0
func (d *driver) Mount(volumeID string, mountpath string) error {
	v, err := d.GetVol(volumeID)
	if err != nil {
		return fmt.Errorf("Failed to locate volume %q", volumeID)
	}
	if err := syscall.Mount(v.DevicePath, mountpath, v.Spec.Format.SimpleString(), 0, ""); err != nil {
		// TODO(pedge): same string for log message and error?
		dlog.Errorf("Mounting %s on %s failed because of %v", v.DevicePath, mountpath, err)
		return fmt.Errorf("Failed to mount %v at %v: %v", v.DevicePath, mountpath, err)
	}

	dlog.Infof("BUSE mounted NBD device %s at %s", v.DevicePath, mountpath)

	v.AttachPath = mountpath
	// TODO(pedge): why ignoring the error?
	err = d.UpdateVol(v)

	return nil
}
Example #2
0
// Handle block requests.
func (nbd *NBD) handle() {
	buf := make([]byte, 2<<19)
	var x request

	for {
		bytes, err := syscall.Read(nbd.socket, buf[0:28])
		if nbd.deviceFile == nil {
			dlog.Infof("Disconnecting device %s", nbd.devicePath)
			return
		}

		if bytes < 0 || err != nil {
			dlog.Errorf("Error reading from device %s", nbd.devicePath)
			nbd.Disconnect()
			return
		}

		x.magic = binary.BigEndian.Uint32(buf)
		x.typus = binary.BigEndian.Uint32(buf[4:8])
		x.handle = binary.BigEndian.Uint64(buf[8:16])
		x.from = binary.BigEndian.Uint64(buf[16:24])
		x.len = binary.BigEndian.Uint32(buf[24:28])

		switch x.magic {
		case NBD_REPLY_MAGIC:
			fallthrough
		case NBD_REQUEST_MAGIC:
			switch x.typus {
			case NBD_CMD_READ:
				nbd.device.ReadAt(buf[16:16+x.len], int64(x.from))
				binary.BigEndian.PutUint32(buf[0:4], NBD_REPLY_MAGIC)
				binary.BigEndian.PutUint32(buf[4:8], 0)
				syscall.Write(nbd.socket, buf[0:16+x.len])
			case NBD_CMD_WRITE:
				n, _ := syscall.Read(nbd.socket, buf[28:28+x.len])
				for uint32(n) < x.len {
					m, _ := syscall.Read(nbd.socket, buf[28+n:28+x.len])
					n += m
				}
				nbd.device.WriteAt(buf[28:28+x.len], int64(x.from))
				binary.BigEndian.PutUint32(buf[0:4], NBD_REPLY_MAGIC)
				binary.BigEndian.PutUint32(buf[4:8], 0)
				syscall.Write(nbd.socket, buf[0:16])
			case NBD_CMD_DISC:
				dlog.Infof("Disconnecting device %s", nbd.devicePath)
				nbd.Disconnect()
				return
			case NBD_CMD_FLUSH:
				fallthrough
			case NBD_CMD_TRIM:
				binary.BigEndian.PutUint32(buf[0:4], NBD_REPLY_MAGIC)
				binary.BigEndian.PutUint32(buf[4:8], 1)
				syscall.Write(nbd.socket, buf[0:16])
			default:
				dlog.Errorf("Unknown command recieved on device %s", nbd.devicePath)
				nbd.Disconnect()
				return
			}
		default:
			dlog.Errorf("Invalid packet command recieved on device %s", nbd.devicePath)
			nbd.Disconnect()
			return
		}
	}
}
Example #3
0
func (l *Layer0) create(id, parent string) (string, *Layer0Vol, error) {
	l.Lock()
	defer l.Unlock()

	// If this is the parent of the Layer0, add an entry for it.
	baseID, l0 := l.isLayer0Parent(id)
	if l0 {
		l.volumes[baseID] = &Layer0Vol{id: baseID, parent: parent}
		return id, nil, nil
	}

	// Don't do anything if this is not layer 0
	if !l.isLayer0(id) {
		return id, nil, nil
	}

	vol, ok := l.volumes[id]
	if !ok {
		dlog.Warnf("Failed to find layer0 volume for id %v", id)
		return id, nil, nil
	}

	// Query volume for Layer 0
	vols, err := l.volDriver.Enumerate(&api.VolumeLocator{Name: vol.parent}, nil)

	// If we don't find a volume configured for this image,
	// then don't track layer0
	if err != nil || vols == nil {
		dlog.Infof("Failed to find configured volume for id %v", vol.parent)
		delete(l.volumes, id)
		return id, nil, nil
	}

	// Find a volume that is available.
	index := -1
	for i, v := range vols {
		if len(v.AttachPath) == 0 {
			index = i
			break
		}
	}
	if index == -1 {
		dlog.Infof("Failed to find free volume for id %v", vol.parent)
		delete(l.volumes, id)
		return id, nil, nil
	}

	mountPath := path.Join(l.home, l.loID(id))
	os.MkdirAll(mountPath, 0755)

	// If this is a block driver, first attach the volume.
	if l.volDriver.Type() == api.DriverType_DRIVER_TYPE_BLOCK {
		_, err := l.volDriver.Attach(vols[index].Id)
		if err != nil {
			dlog.Errorf("Failed to attach volume %v", vols[index].Id)
			delete(l.volumes, id)
			return id, nil, nil
		}
	}
	err = l.volDriver.Mount(vols[index].Id, mountPath)
	if err != nil {
		dlog.Errorf("Failed to mount volume %v at path %v",
			vols[index].Id, mountPath)
		delete(l.volumes, id)
		return id, nil, nil
	}
	vol.path = mountPath
	vol.volumeID = vols[index].Id
	vol.ref = 1

	return l.realID(id), vol, nil
}