Apply the vhost group parameter for the vhost_sockets directory creation

Directory /var/lib/vhost_sockets will be used to create vhost sockets
which should have the the group name as hugetlbfs, which is common
between qemu and openvswitch to share the vhost_sockets. And the
correct selinux context to be applied on the vhost_sockets directory.
Closes-Bug: #1751711
Change-Id: Ib917cf86bd9a4ce57af243ab43337ea6c88bf76c

docker/services/nova-libvirt.yaml

@@ -116,7 +116,15 @@ parameters:
                  the InternalTLSVncCAFile parameter) is not desired. The current
                  default reflects TripleO's default CA, which is FreeIPA.
                  It will only be used if internal TLS is enabled.
-
+  VhostuserSocketGroup:
+    default: "qemu"
+    description: >
+      The vhost-user socket directory group name.
+      Defaults to 'qemu'. When vhostuser mode is 'dpdkvhostuserclient'
+      (which is the default mode), the vhost socket is created by qemu.
+    type: string
+    tags:
+      - role_specific
 
 conditions:
 
@@ -159,6 +167,18 @@ conditions:
 
 
 resources:
+  RoleParametersValue:
+    type: OS::Heat::Value
+    properties:
+      type: json
+      value:
+        map_replace:
+          - map_replace:
+            - vhostuser_socket_group: VhostuserSocketGroup
+            - values: {get_param: [RoleParameters]}
+          - values:
+              VhostuserSocketGroup: {get_param: VhostuserSocketGroup}
+
 
   ContainersCommon:
     type: ./containers-common.yaml
@@ -396,7 +416,9 @@ outputs:
             path: /var/lib/vhost_sockets
             state: directory
             owner: qemu
-            group: qemu
+            group: {get_attr: [RoleParametersValue, value, vhostuser_socket_group]}
+            setype: virt_cache_t
+            seuser: system_u
         - name: ensure ceph configurations exist
           file:
             path: /etc/ceph