Add per-guest S3/S4 state configuration

There is a new <pm/> element implemented that can control what ACPI
sleeping states will be advertised by BIOS and allowed to be switched
to by libvirt. The default keeps defaults on hypervisor, otherwise
forces chosen setting.
The documentation of the pm element is added as well.

docs/formatdomain.html.in

@@ -960,6 +960,30 @@
         domain will be restarted with the same configuration</dd>
     </dl>
 
+    <h3><a name="elementsPowerManagement">Power Management</a></h3>
+
+    <p>
+      <span class="since">Since 0.10.2</span> it is possible to
+      forcibly enable or disable BIOS advertisements to the guest
+      OS. (NB: Only qemu driver support)
+    </p>
+
+<pre>
+  ...
+  &lt;pm&gt;
+    &lt;suspend-to-disk enabled='no'/&gt;
+    &lt;suspend-to-ram enabled='yes'/&gt;
+  &lt;/pm&gt;
+  ...</pre>
+
+    <dl>
+      <dt><code>pm</code></dt>
+      <dd>These elements enable ('yes') or disable ('no') BIOS support
+        for S3 (suspend-to-disk) and S4 (suspend-to-mem) ACPI sleep
+        states. If nothing is specified, then the hypervisor will be
+        left with its default value.</dd>
+    </dl>
+
     <h3><a name="elementsFeatures">Hypervisor features</a></h3>
 
     <p>

docs/schemas/domaincommon.rng

@@ -52,6 +52,9 @@
         <ref name="resources"/>
         <ref name="features"/>
         <ref name="termination"/>
+        <optional>
+          <ref name="pm"/>
+        </optional>
         <optional>
           <ref name="devices"/>
         </optional>
@@ -2271,6 +2274,40 @@
       <value>coredump-restart</value>
     </choice>
   </define>
+  <!--
+      Control ACPI sleep states (dis)allowed for the domain
+      For each of the states the following rules apply:
+      on: the state will be forcefully enabled
+      off: the state will be forcefully disabled
+      not specified: hypervisor will be left to decide its defaults
+  -->
+  <define name="pm">
+    <element name="pm">
+      <interleave>
+        <optional>
+          <element name="suspend-to-mem">
+            <ref name="suspendChoices"/>
+          </element>
+        </optional>
+        <optional>
+          <element name="suspend-to-disk">
+            <ref name="suspendChoices"/>
+          </element>
+        </optional>
+      </interleave>
+      <empty/>
+    </element>
+  </define>
+  <define name="suspendChoices">
+    <optional>
+      <attribute name="enabled">
+        <choice>
+          <value>yes</value>
+          <value>no</value>
+        </choice>
+      </attribute>
+    </optional>
+  </define>
   <!--
       Specific setup for a qemu emulated character device.  Note: this
       definition doesn't fully specify the constraints on this node.

src/conf/domain_conf.c

@@ -124,6 +124,11 @@ VIR_ENUM_IMPL(virDomainLifecycleCrash, VIR_DOMAIN_LIFECYCLE_CRASH_LAST,
               "coredump-destroy",
               "coredump-restart")
 
+VIR_ENUM_IMPL(virDomainPMState, VIR_DOMAIN_PM_STATE_LAST,
+              "default",
+              "yes",
+              "no")
+
 VIR_ENUM_IMPL(virDomainDevice, VIR_DOMAIN_DEVICE_LAST,
               "none",
               "disk",
@@ -7239,6 +7244,28 @@ static int virDomainLifecycleParseXML(xmlXPathContextPtr ctxt,
     return 0;
 }
 
+static int
+virDomainPMStateParseXML(xmlXPathContextPtr ctxt,
+                         const char *xpath,
+                         int *val)
+{
+    int ret = -1;
+    char *tmp = virXPathString(xpath, ctxt);
+    if (tmp) {
+        *val = virDomainPMStateTypeFromString(tmp);
+        if (*val < 0) {
+            virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+                           _("unknown PM state value %s"), tmp);
+            goto cleanup;
+        }
+    }
+
+    ret = 0;
+ cleanup:
+    VIR_FREE(tmp);
+    return ret;
+}
+
 virDomainDeviceDefPtr virDomainDeviceDefParse(virCapsPtr caps,
                                               virDomainDefPtr def,
                                               const char *xmlStr,
@@ -8611,6 +8638,16 @@ static virDomainDefPtr virDomainDefParseXML(virCapsPtr caps,
                                    virDomainLifecycleCrashTypeFromString) < 0)
         goto error;
 
+    if (virDomainPMStateParseXML(ctxt,
+                                 "string(./pm/suspend-to-mem/@enabled)",
+                                 &def->pm.s3) < 0)
+        goto error;
+
+    if (virDomainPMStateParseXML(ctxt,
+                                 "string(./pm/suspend-to-disk/@enabled)",
+                                 &def->pm.s4) < 0)
+        goto error;
+
     tmp = virXPathString("string(./clock/@offset)", ctxt);
     if (tmp) {
         if ((def->clock.offset = virDomainClockOffsetTypeFromString(tmp)) < 0) {
@@ -13424,6 +13461,19 @@ virDomainDefFormatInternal(virDomainDefPtr def,
                                     virDomainLifecycleCrashTypeToString) < 0)
         goto cleanup;
 
+    if (def->pm.s3 || def->pm.s4) {
+        virBufferAddLit(buf, "  <pm>\n");
+        if (def->pm.s3) {
+            virBufferAsprintf(buf, "    <suspend-to-mem enabled='%s'/>\n",
+                              virDomainPMStateTypeToString(def->pm.s3));
+        }
+        if (def->pm.s4) {
+            virBufferAsprintf(buf, "    <suspend-to-disk enabled='%s'/>\n",
+                              virDomainPMStateTypeToString(def->pm.s4));
+        }
+        virBufferAddLit(buf, "  </pm>\n");
+    }
+
     virBufferAddLit(buf, "  <devices>\n");
 
     virBufferEscapeString(buf, "    <emulator>%s</emulator>\n",

src/conf/domain_conf.h

@@ -1371,6 +1371,14 @@ enum virDomainLifecycleCrashAction {
     VIR_DOMAIN_LIFECYCLE_CRASH_LAST
 };
 
+enum virDomainPMState {
+    VIR_DOMAIN_PM_STATE_DEFAULT = 0,
+    VIR_DOMAIN_PM_STATE_ENABLED,
+    VIR_DOMAIN_PM_STATE_DISABLED,
+
+    VIR_DOMAIN_PM_STATE_LAST,
+};
+
 enum virDomainBIOSUseserial {
     VIR_DOMAIN_BIOS_USESERIAL_DEFAULT = 0,
     VIR_DOMAIN_BIOS_USESERIAL_YES,
@@ -1625,6 +1633,12 @@ struct _virDomainDef {
     int onPoweroff;
     int onCrash;
 
+    struct {
+        /* These options are actually type of enum virDomainPMState */
+        int s3;
+        int s4;
+    } pm;
+
     virDomainOSDef os;
     char *emulator;
     int features;
@@ -2092,6 +2106,7 @@ VIR_ENUM_DECL(virDomainBoot)
 VIR_ENUM_DECL(virDomainFeature)
 VIR_ENUM_DECL(virDomainLifecycle)
 VIR_ENUM_DECL(virDomainLifecycleCrash)
+VIR_ENUM_DECL(virDomainPMState)
 VIR_ENUM_DECL(virDomainDevice)
 VIR_ENUM_DECL(virDomainDeviceAddress)
 VIR_ENUM_DECL(virDomainDisk)

src/libvirt_private.syms

@@ -453,6 +453,8 @@ virDomainPausedReasonTypeFromString;
 virDomainPausedReasonTypeToString;
 virDomainPciRombarModeTypeFromString;
 virDomainPciRombarModeTypeToString;
+virDomainPMStateTypeFromString;
+virDomainPMStateTypeToString;
 virDomainRedirdevBusTypeFromString;
 virDomainRedirdevBusTypeToString;
 virDomainRemoveInactive;