manila/manila/scheduler/filters/consistency_group.py

55 lines
2.0 KiB
Python

# Copyright (c) 2015 Alex Meade
# All Rights Reserved.
#
# 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.
from oslo_log import log
from manila.scheduler.filters import base_host
from manila.share import utils as share_utils
LOG = log.getLogger(__name__)
class ConsistencyGroupFilter(base_host.BaseHostFilter):
"""ConsistencyGroupFilter filters host based on compatibility with CG."""
def host_passes(self, host_state, filter_properties):
"""Return True if host will work with desired consistency group."""
cg = filter_properties.get('consistency_group')
cg_support = filter_properties.get('cg_support')
# NOTE(ameade): If creating a share not in a CG, then of course the
# host is valid for the cg.
if not cg:
return True
# NOTE(ameade): If the CG host can only support shares on the same
# pool, then the only valid pool is that one.
if cg_support == 'pool' and cg.get('host') == host_state.host:
return True
# NOTE(ameade): If the CG host can support shares on the same host,
# then any pool on that backend will work.
elif cg_support == 'host':
cg_backend = share_utils.extract_host(cg['host'])
host_backend = share_utils.extract_host(host_state.host)
return cg_backend == host_backend
LOG.debug("Host %(host)s is not compatible with consistency "
"group %(cg)s"
% {"host": host_state.host, "cg": cg['id']})
return False