Initial changes for testing VM creation for CentOS

Adding updates to the VM creation steps to hopefully allow for
CentOS test VMs to be able to be fired up.  Also refactors basic
OS support for the module to be more flexible by loading defaults
from files.

Change-Id: Ie4456d199dd3d965e533070f4321f50075dfe1df

playbooks/roles/bifrost-create-vm-nodes/defaults/required_defaults_CentOS.yml

@@ -0,0 +1,20 @@
+---
+libvirt_service_name: libvirtd
+required_packages:
+ - qemu-img
+ - qemu-kvm-tools
+ - qemu-kvm
+ - qemu-kvm-common
+ - sgabios
+ - libvirt
+ - libvirt-client
+ - libvirt-daemon
+ - libvirt-daemon-config-network
+ - libvirt-daemon-config-nwfilter
+ - libvirt-daemon-driver-network
+ - libvirt-daemon-driver-nodedev
+ - libvirt-daemon-driver-nwfilter
+ - libvirt-daemon-driver-qemu
+ - libvirt-daemon-driver-secret
+ - libvirt-daemon-driver-storage
+ - libvirt-daemon-kvm

playbooks/roles/bifrost-create-vm-nodes/defaults/required_defaults_Debian.yml

@@ -0,0 +1,8 @@
+---
+libvirt_service_name: libvirt-bin
+required_packages:
+ - libvirt-bin
+ - qemu-utils
+ - qemu-kvm
+ - qemu-system-x86
+ - sgabios

playbooks/roles/bifrost-create-vm-nodes/defaults/required_defaults_RedHat.yml

@@ -0,0 +1,12 @@
+---
+libvirt_service_name: libvirtd
+required_packages:
+ - qemu-img
+ - qemu-kvm-tools
+ - qemu-kvm
+ - qemu-kvm-common
+ - qemu-system-x86
+ - sgabios
+ - libvirt
+ - libvirt-client
+ - libvirt-daemon

playbooks/roles/bifrost-create-vm-nodes/files/create_vm_nodes-for-role.sh

@@ -38,6 +38,15 @@ VM_EMULATOR=${VM_EMULATOR:-/usr/bin/qemu-system-x86_64}
 VM_CPU=${VM_CPU:-1}
 VM_RAM=${VM_RAM:-3072}
 VM_DISK=${VM_DISK:-10}
+VM_MACHINE="pc-1.0"
+
+# CentOS provides a single emulator package
+# which differs from other distributions, and
+# needs to be explicitly set.
+if [ -e /etc/centos-release ]; then
+  VM_EMULATOR=/usr/libexec/qemu-kvm
+  VM_MACHINE="pc"
+fi
 
 # VM network
 VM_NET_BRIDGE=${VM_NET_BRIDGE:-default}
@@ -95,6 +104,12 @@ function create_node {
 
     if [ -n "$LOGDIR" ] ; then
       mkdir -p "$LOGDIR"
+      if [ -e /etc/centos-release ]; then
+        # NOTE(TheJulia): For some unknown reason, libvirt's log folder permissions
+        # on CentOS ship in an inoperable state.  Users must be able to read a folder
+        # to open files in the folder structure.
+        chmod o+rx "$LOGDIR/.."
+      fi
     fi
 
     PREALLOC=
@@ -112,15 +127,20 @@ function create_node {
       volume_path=$(virsh vol-path --pool $LIBVIRT_STORAGE_POOL $VOL_NAME)
       # Pre-touch the VM to set +C, as it can only be set on empty files.
       touch "$volume_path"
-      chattr +C "$volume_path" || true
 
+      # NOTE(TheJulia): CentOS default installs with an XFS root, and chattr
+      # fails to set +C on XFS.  This could be more elegent, however the use
+      # case is for CI testing.
+      if [ ! -e /etc/centos-release ]; then
+        chattr +C "$volume_path" || true
+      fi
       vm_xml="
 <domain type='qemu'>
   <name>${NAME}</name>
   <memory unit='KiB'>${MEM}</memory>
   <vcpu>${CPU}</vcpu>
   <os>
-    <type arch='${ARCH}' machine='pc-1.0'>hvm</type>
+    <type arch='${ARCH}' machine='${VM_MACHINE}'>hvm</type>
     <boot dev='network'/>
     <bootmenu enable='no'/>
     <bios useserial='yes'/>

playbooks/roles/bifrost-create-vm-nodes/tasks/main.yml

@@ -14,27 +14,16 @@
 #
 # TODO: Consider converting to ansible virt module.
 ---
-- name: "Install testing apt packages for Ubuntu/Debian"
-  when: ansible_os_family == 'Debian'
-  apt: name={{ item }} state=present
-  with_items:
-    - libvirt-bin
-    - qemu-utils
-    - qemu-kvm
-    - qemu-system-x86
-    - sgabios
-- name: "Install testing yum packages for RedHat/CentOS/Fedora/OpenSuse"
-  when: ansible_os_family in ['CentOS', 'Fedora', 'OpenSuse', 'RedHat']
-  yum: name={{ item }} state=present
-  with_items:
-    - libvirt-client
-    - qemu-img
-    - qemu-kvm-tools
-    - qemu-kvm
-    - qemu-system-x86
-    - sgabios
+- name: "Load Distribution defaults"
+  include_vars: "{{ item }}"
+  with_first_found:
+    - "../defaults/required_defaults_{{ ansible_distribution }}.yml"
+    - "../defaults/required_defaults_{{ ansible_os_family }}.yml"
+- name: "Install required packages"
+  action: "{{ ansible_pkg_mgr }} name={{item}} state=present"
+  with_items: required_packages
 - name: "Restart libvirt service"
-  service: name=libvirt-bin state=restarted
+  service: name={{libvirt_service_name}} state=restarted
 - name: "Create virtual machines"
   script: create_vm_nodes-for-role.sh
   environment: