Synnefo » snf-ganeti

  def _GenerateKVMBlockDevicesOptions(self, instance, block_devices, kvmhelp):

    hvp = instance.hvparams

    boot_disk = hvp[constants.HV_BOOT_ORDER] == constants.HT_BO_DISK

    # whether this is an older KVM version that uses the boot=on flag

    # on devices

    needs_boot_flag = self._BOOT_RE.search(kvmhelp)

    dev_opts = []

    disk_type = hvp[constants.HV_DISK_TYPE]

    if disk_type == constants.HT_DISK_PARAVIRTUAL:

      if_val = ",if=%s" % self._VIRTIO

    else:

      if_val = ",if=%s" % disk_type

    # Cache mode

    disk_cache = hvp[constants.HV_DISK_CACHE]

    if instance.disk_template in constants.DTS_EXT_MIRROR:

      if disk_cache != "none":

        # TODO: make this a hard error, instead of a silent overwrite

        logging.warning("KVM: overriding disk_cache setting '%s' with 'none'"

                        " to prevent shared storage corruption on migration",

                        disk_cache)

      cache_val = ",cache=none"

    elif disk_cache != constants.HT_CACHE_DEFAULT:

      cache_val = ",cache=%s" % disk_cache

    else:

      cache_val = ""

    for cfdev, dev_path in block_devices:

      if cfdev.mode != constants.DISK_RDWR:

        raise errors.HypervisorError("Instance has read-only disks which"

                                     " are not supported by KVM")

      # TODO: handle FD_LOOP and FD_BLKTAP (?)

      boot_val = ""

      if boot_disk:

        dev_opts.extend(["-boot", "c"])

        boot_disk = False

        if needs_boot_flag and disk_type != constants.HT_DISK_IDE:

          boot_val = ",boot=on"

      drive_val = "file=%s,format=raw%s%s%s" % \

                  (dev_path, if_val, boot_val, cache_val)

      dev_opts.extend(["-drive", drive_val])

    return dev_opts

      boot_cdrom = boot_floppy = boot_network = False

    bdev_opts = self._GenerateKVMBlockDevicesOptions(instance,

                                                     block_devices,

                                                     kvmhelp)

    kvm_cmd.extend(bdev_opts)