Added bare-metal host manager.

Part 6 of 6: blueprint general-bare-metal-provisioning-framework.

The bare-metal host manager is used when multiple bare-metal
instances are created by one request. The bare-metal host manager
detects if a nova-compute is for VM or bare-metal.
For VM instance provisioning, it simply calls the original host_manager.
For bare-metal instance provisioning, BaremetalNodeState is used
to manage bare-metal node's resources when an instance is provisioned
to a bare-metal node.

Change-Id: Ib207f495493db99a4a6cd1ac0044662fb7397322
Co-authored-by: Mikyung Kang <mkkang@isi.edu>
Co-authored-by: David Kang <dkang@isi.edu>
Co-authored-by: Ken Igarashi <igarashik@nttdocomo.co.jp>
Co-authored-by: Arata Notsu <notsu@virtualtech.jp>

nova/scheduler/baremetal_host_manager.py

@@ -0,0 +1,77 @@
+# Copyright (c) 2012 NTT DOCOMO, INC.
+# Copyright (c) 2011 OpenStack, LLC.
+# 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.
+
+"""
+Manage hosts in the current zone.
+"""
+
+from nova import flags
+from nova.openstack.common import log as logging
+from nova.scheduler import host_manager
+
+
+FLAGS = flags.FLAGS
+LOG = logging.getLogger(__name__)
+
+
+class BaremetalNodeState(host_manager.HostState):
+    """Mutable and immutable information tracked for a host.
+    This is an attempt to remove the ad-hoc data structures
+    previously used and lock down access.
+    """
+
+    def update_from_compute_node(self, compute):
+        """Update information about a host from its compute_node info."""
+        all_ram_mb = compute['memory_mb']
+
+        free_disk_mb = compute['free_disk_gb'] * 1024
+        free_ram_mb = compute['free_ram_mb']
+
+        self.free_ram_mb = free_ram_mb
+        self.total_usable_ram_mb = all_ram_mb
+        self.free_disk_mb = free_disk_mb
+        self.vcpus_total = compute['vcpus']
+        self.vcpus_used = compute['vcpus_used']
+
+    def consume_from_instance(self, instance):
+        self.free_ram_mb = 0
+        self.free_disk_mb = 0
+        self.vcpus_used = self.vcpus_total
+
+
+def new_host_state(self, host, node, capabilities=None, service=None):
+    """Returns an instance of BaremetalHostState or HostState according to
+    capabilities. If 'baremetal_driver' is in capabilities, it returns an
+    instance of BaremetalHostState. If not, returns an instance of HostState.
+    """
+    if capabilities is None:
+        capabilities = {}
+    cap = capabilities.get('compute', {})
+    if bool(cap.get('baremetal_driver')):
+        return BaremetalNodeState(host, node, capabilities, service)
+    else:
+        return host_manager.HostState(host, node, capabilities, service)
+
+
+class BaremetalHostManager(host_manager.HostManager):
+    """Bare-Metal HostManager class."""
+
+    # Override.
+    # Yes, this is not a class, and it is OK
+    host_state_cls = new_host_state
+
+    def __init__(self):
+        super(BaremetalHostManager, self).__init__()