nova/nova/virt/vmwareapi/volume_util.py

# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright (c) 2012 VMware, Inc.
#
#    Licensed under the Apache License, Version 2.0 (the "License"); you may
#    not use this file except in compliance with the License. You may obtain
#    a copy of the License at
#
#         http://www.apache.org/licenses/LICENSE-2.0
#
#    Unless required by applicable law or agreed to in writing, software
#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
#    License for the specific language governing permissions and limitations
#    under the License.

"""
Helper methods for operations related to the management of volumes,
and storage repositories
"""

import re
import string

from nova.openstack.common import log as logging
from nova.virt.vmwareapi import vim_util
from nova.virt.vmwareapi import vm_util

LOG = logging.getLogger(__name__)


class StorageError(Exception):
    """To raise errors related to Volume commands."""

    def __init__(self, message=None):
        super(StorageError, self).__init__(message)


def get_host_iqn(session, cluster=None):
    """
    Return the host iSCSI IQN.
    """
    host_mor = vm_util.get_host_ref(session, cluster)
    hbas_ret = session._call_method(vim_util, "get_dynamic_property",
                                    host_mor, "HostSystem",
                                    "config.storageDevice.hostBusAdapter")

    # Meaning there are no host bus adapters on the host
    if hbas_ret is None:
        return
    host_hbas = hbas_ret.HostHostBusAdapter
    if not host_hbas:
        return
    for hba in host_hbas:
        if hba.__class__.__name__ == 'HostInternetScsiHba':
            return hba.iScsiName


def find_st(session, data, cluster=None):
    """
    Return the iSCSI Target given a volume info.
    """
    target_portal = data['target_portal']
    target_iqn = data['target_iqn']
    host_mor = vm_util.get_host_ref(session, cluster)

    lst_properties = ["config.storageDevice.hostBusAdapter",
                      "config.storageDevice.scsiTopology",
                      "config.storageDevice.scsiLun"]
    props = session._call_method(vim_util, "get_object_properties",
                       None, host_mor, "HostSystem",
                       lst_properties)
    result = (None, None)
    hbas_ret = None
    scsi_topology = None
    scsi_lun_ret = None
    for elem in props:
        for prop in elem.propSet:
            if prop.name == "config.storageDevice.hostBusAdapter":
                hbas_ret = prop.val
            elif prop.name == "config.storageDevice.scsiTopology":
                scsi_topology = prop.val
            elif prop.name == "config.storageDevice.scsiLun":
                scsi_lun_ret = prop.val

    # Meaning there are no host bus adapters on the host
    if hbas_ret is None:
        return result
    host_hbas = hbas_ret.HostHostBusAdapter
    if not host_hbas:
        return result
    for hba in host_hbas:
        if hba.__class__.__name__ == 'HostInternetScsiHba':
            hba_key = hba.key
            break
    else:
        return result

    if scsi_topology is None:
        return result
    host_adapters = scsi_topology.adapter
    if not host_adapters:
        return result
    scsi_lun_key = None
    for adapter in host_adapters:
        if adapter.adapter == hba_key:
            if not getattr(adapter, 'target', None):
                return result
            for target in adapter.target:
                if (getattr(target.transport, 'address', None) and
                    target.transport.address[0] == target_portal and
                    target.transport.iScsiName == target_iqn):
                    if not target.lun:
                        return result
                    for lun in target.lun:
                        if 'host.ScsiDisk' in lun.scsiLun:
                            scsi_lun_key = lun.scsiLun
                            break
                    break
            break

    if scsi_lun_key is None:
        return result

    if scsi_lun_ret is None:
        return result
    host_scsi_luns = scsi_lun_ret.ScsiLun
    if not host_scsi_luns:
        return result
    for scsi_lun in host_scsi_luns:
        if scsi_lun.key == scsi_lun_key:
            return (scsi_lun.deviceName, scsi_lun.uuid)

    return result


def rescan_iscsi_hba(session, cluster=None):
    """
    Rescan the iSCSI HBA to discover iSCSI targets.
    """
    host_mor = vm_util.get_host_ref(session, cluster)
    storage_system_mor = session._call_method(vim_util, "get_dynamic_property",
                                              host_mor, "HostSystem",
                                              "configManager.storageSystem")
    hbas_ret = session._call_method(vim_util,
                                    "get_dynamic_property",
                                    storage_system_mor,
                                    "HostStorageSystem",
                                    "storageDeviceInfo.hostBusAdapter")
    # Meaning there are no host bus adapters on the host
    if hbas_ret is None:
        return
    host_hbas = hbas_ret.HostHostBusAdapter
    if not host_hbas:
        return
    for hba in host_hbas:
        if hba.__class__.__name__ == 'HostInternetScsiHba':
            hba_device = hba.device
            break
    else:
        return

    LOG.debug(_("Rescanning HBA %s") % hba_device)
    session._call_method(session._get_vim(), "RescanHba", storage_system_mor,
                         hbaDevice=hba_device)
    LOG.debug(_("Rescanned HBA %s ") % hba_device)


def mountpoint_to_number(mountpoint):
    """Translate a mountpoint like /dev/sdc into a numeric."""
    if mountpoint.startswith('/dev/'):
        mountpoint = mountpoint[5:]
    if re.match('^[hsv]d[a-p]$', mountpoint):
        return (ord(mountpoint[2:3]) - ord('a'))
    elif re.match('^[0-9]+$', mountpoint):
        return string.atoi(mountpoint, 10)
    else:
        LOG.warn(_("Mountpoint cannot be translated: %s") % mountpoint)
        return -1