Skip Trilio dirs when setting ownership in /var/lib/nova

Trilio currently mounts an NFS export in /var/lib/nova to make it accessible
from within the nova_compute and nova_libvirt containers.
This can result in considerable delays when walking the directory tree to
ensure the ownership is correct.

This patch adds the ability to skip paths when recursively setting the
ownership and selinux context in /var/lib/nova. The list of paths to skip
can be set via te NovaStatedirOwnershipSkip heat parameter. This default to
the Trilio dir.

Change-Id: Ic6f053d56194613046ae0a4a908206ebb453fcf4

container_config_scripts/nova_statedir_ownership.py

@@ -137,7 +137,8 @@ class NovaStatedirOwnershipManager(object):
        docker nova uid/gid is not known in this context).
     """
     def __init__(self, statedir, upgrade_marker='upgrade_marker',
-                 nova_user='nova', secontext_marker='../_nova_secontext'):
+                 nova_user='nova', secontext_marker='../_nova_secontext',
+                 exclude_paths=None):
         self.statedir = statedir
         self.nova_user = nova_user
 
@@ -145,6 +146,13 @@ class NovaStatedirOwnershipManager(object):
         self.secontext_marker_path = os.path.normpath(os.path.join(statedir, secontext_marker))
         self.upgrade = os.path.exists(self.upgrade_marker_path)
 
+        self.exclude_paths = [self.upgrade_marker_path]
+        if exclude_paths is not None:
+            for p in exclude_paths:
+                if not p.startswith(os.path.sep):
+                    p = os.path.join(self.statedir, p)
+                self.exclude_paths.append(p)
+
         self.target_uid, self.target_gid = self._get_nova_ids()
         self.previous_uid, self.previous_gid = self._get_previous_nova_ids()
         self.id_change = (self.target_uid, self.target_gid) != \
@@ -172,7 +180,7 @@ class NovaStatedirOwnershipManager(object):
         for f in os.listdir(top):
             pathname = os.path.join(top, f)
 
-            if pathname == self.upgrade_marker_path:
+            if pathname in self.exclude_paths:
                 continue
 
             try:
@@ -228,5 +236,12 @@ class NovaStatedirOwnershipManager(object):
         LOG.info('Nova statedir ownership complete')
 
 
+def get_exclude_paths():
+    exclude_paths = os.environ.get('NOVA_STATEDIR_OWNERSHIP_SKIP')
+    if exclude_paths is not None:
+        exclude_paths = exclude_paths.split(os.pathsep)
+    return exclude_paths
+
+
 if __name__ == '__main__':
-    NovaStatedirOwnershipManager('/var/lib/nova').run()
+    NovaStatedirOwnershipManager('/var/lib/nova', exclude_paths=get_exclude_paths())

container_config_scripts/tests/test_nova_statedir_ownership.py

@@ -16,6 +16,7 @@
 from unittest import mock
 
 import contextlib
+import os
 from os import stat as orig_stat
 import six
 import stat
@@ -36,6 +37,7 @@ class FakeSelinux(object):
 
 sys.modules["selinux"] = FakeSelinux
 
+from container_config_scripts.nova_statedir_ownership import get_exclude_paths  # noqa: E402
 from container_config_scripts.nova_statedir_ownership import \
     NovaStatedirOwnershipManager  # noqa: E402
 from container_config_scripts.nova_statedir_ownership import PathManager  # noqa: E402
@@ -395,3 +397,31 @@ class NovaStatedirOwnershipManagerTestCase(base.BaseTestCase):
             for fn, expected in six.iteritems(expected_changes):
                 assert_ids(testtree, fn, expected[0], expected[1])
             fake_unlink.assert_called_with('/var/lib/nova/upgrade_marker')
+
+    def test_exclude_path(self):
+        testtree = generate_testtree1(current_uid, current_gid)
+
+        with fake_testtree(testtree) as (
+                fake_chown, _, fake_listdir, fake_stat, _, _, _):
+            manager = NovaStatedirOwnershipManager(
+                '/var/lib/nova',
+                exclude_paths=['instances/foo/bar', '/var/lib/nova/instances/foo/removeddir']
+            )
+            manager.run()
+            self.assertIn('/var/lib/nova/instances/foo/bar', manager.exclude_paths)
+            self.assertIn('/var/lib/nova/instances/foo/removeddir', manager.exclude_paths)
+            self.assertNotIn(mock.call('/var/lib/nova/instances/foo/bar'), fake_stat.call_args_list)
+            self.assertNotIn(mock.call('/var/lib/nova/instances/foo/bar'), fake_chown.call_args_list)
+            self.assertNotIn(mock.call('/var/lib/nova/instances/foo/removeddir'), fake_stat.call_args_list)
+            self.assertNotIn(mock.call('/var/lib/nova/instances/foo/removeddir'), fake_chown.call_args_list)
+            self.assertNotIn(mock.call('/var/lib/nova/instances/foo/removeddir'), fake_listdir.call_args_list)
+
+    @mock.patch.dict(os.environ, {'NOVA_STATEDIR_OWNERSHIP_SKIP': 'foo:bar:foo/bar/baz'})
+    def test_get_exclude_paths(self):
+        expected = [
+            'foo',
+            'bar',
+            'foo/bar/baz'
+        ]
+        exclude_paths = get_exclude_paths()
+        self.assertEqual(exclude_paths, expected)

deployment/nova/nova-compute-container-puppet.yaml

@@ -500,6 +500,13 @@ parameters:
     default: false
     tags:
       - role_specific
+  NovaStatedirOwnershipSkip:
+    type: comma_delimited_list
+    description: >
+      List of paths relative to nova_statedir to ignore when recursively setting the
+      ownership and selinux context.
+    default:
+      - 'triliovault-mounts'
 
   # DEPRECATED: the following options are deprecated and are currently maintained
   # for backwards compatibility. They will be removed in future release.
@@ -917,6 +924,10 @@ outputs:
                   expression: str($.data.debug)
                   data:
                     debug: {get_attr: [NovaBase, role_data, config_settings, 'nova::logging::debug']}
+              NOVA_STATEDIR_OWNERSHIP_SKIP:
+                list_join:
+                  - ':'
+                  - {get_param: NovaStatedirOwnershipSkip}
         step_5:
           map_merge:
             - nova_compute: