Load known, standard kernel modules from the host, not within containers

Known kernel modules are:
- dm-multipath (for multipathd)
- ip_vs (for keepalived)
- iscsi_tcp (for ironic-conductor)
- openvswitch (for openvswitch-vswitchd)

Change-Id: I1841ec30cde142c8019830ad3190847dfe493eb9

ansible/roles/haproxy/tasks/config.yml

@@ -65,6 +65,13 @@
   notify:
     - Restart haproxy container
 
+- name: Load and persist keepalived module
+  import_role:
+    role: module-load
+  vars:
+    modules:
+      - {'name': ip_vs }
+
 - name: Copying over keepalived.conf
   vars:
     service: "{{ haproxy_services['keepalived'] }}"

ansible/roles/ironic/tasks/config.yml

@@ -1,4 +1,11 @@
 ---
+- name: Load and persist iscsi_tcp module
+  import_role:
+    role: module-load
+  vars:
+    modules:
+      - {'name': iscsi_tcp}
+
 - name: Ensuring config directories exist
   file:
     path: "{{ node_config_directory }}/{{ item.key }}"

ansible/roles/module-load/defaults/main.yaml

@@ -0,0 +1,7 @@
+---
+# Module name as a list of hashes:
+# modules:
+#   - { name: foo, params: 'bar baz' }
+#   - { name: starwars }
+#   - { name: starwars, state: absent }
+modules: []

ansible/roles/module-load/tasks/main.yaml

@@ -0,0 +1,56 @@
+---
+# Allow to get a clean way to load and persist kernel modules
+
+- name: Run tasks only for specific kolla_action
+  when:
+    - kolla_action != "config"
+  block:
+    - name: Check whether /etc/modules-load.d exists
+      stat:
+        path: /etc/modules-load.d
+      register: modules_load_stat
+
+    - name: "Load modules"
+      become: true
+      modprobe:
+        name: "{{ item.name }}"
+        params: "{{ item.params | default(omit) }}"
+        state: "{{ item.state | default('present') }}"
+      loop: "{{ modules }}"
+      loop_control:
+        label: "{{ item.name }}"
+
+    - name: "Persist modules via modules-load.d"
+      become: true
+      template:
+        dest: "/etc/modules-load.d/{{ item.name }}.conf"
+        src: module-load.conf.j2
+      loop: "{{ modules }}"
+      loop_control:
+        label: "{{ item.name }}"
+      when:
+        - modules_load_stat.stat.exists
+        - (item.state | default('present')) == 'present'
+
+    - name: "Drop module persistence"
+      become: true
+      file:
+        path: "/etc/modules-load.d/{{ item.name }}.conf"
+        state: absent
+      loop: "{{ modules }}"
+      loop_control:
+        label: "{{ item.name }}"
+      when:
+        - modules_load_stat.stat.exists
+        - (item.state | default('present')) == 'absent'
+
+    - name: "Persist modules via /etc/modules"
+      become: true
+      lineinfile:
+        dest: /etc/modules
+        line: "{{ item.name }} {{ item.params | default('') }}"
+        state: "{{ item.state | default('present') }}"
+      loop: "{{ modules }}"
+      loop_control:
+        label: "{{ item.name }}"
+      when: not modules_load_stat.stat.exists

ansible/roles/module-load/templates/module-load.conf.j2

@@ -0,0 +1,2 @@
+# {{ ansible_managed }}
+{{ item.name }} {{ item.params |default('') }}

ansible/roles/multipathd/tasks/config.yml

@@ -1,4 +1,11 @@
 ---
+- name: Load and persist dm-multipath module
+  import_role:
+    role: module-load
+  vars:
+    modules:
+      - {'name': dm-multipath}
+
 - name: Ensuring config directories exist
   file:
     path: "{{ node_config_directory }}/{{ item }}"

ansible/roles/openvswitch/tasks/config.yml

@@ -1,4 +1,11 @@
 ---
+- name: Load and persist openvswitch module
+  import_role:
+    role: module-load
+  vars:
+    modules:
+      - {'name': openvswitch}
+
 - name: Ensuring config directories exist
   become: true
   file:

releasenotes/notes/module-load-946eaecb55cb31f0.yaml

@@ -0,0 +1,5 @@
+---
+features:
+  - Adds support for loading kernel modules required by containers. This is
+    required since kolla images are removing support for loading kernel modules
+    from within the container.