domaincaps: Expose UEFI capability

As of 54289916 we learned libvirt to use UEFI for domains.
However, management applications may firstly query if libvirt
supports it. And this is where virConnectGetDomainCapabilities()
API comes handy.
Signed-off-by: NMichal Privoznik <mprivozn@redhat.com>

docs/formatdomaincaps.html.in

@@ -93,6 +93,46 @@
       <dd>The maximum number of supported virtual CPUs</dd>
     </dl>
 
+    <h3><a name="elementsOSBIOS">BIOS bootloader</a></h3>
+
+    <p>Sometimes users might want to tweak some BIOS knobs or use
+    UEFI. For cases like that, <a
+    href="formatdomain.html#elementsOSBIOS"><code>os</code></a>
+    element exposes what values can be passed to its children.</p>
+
+<pre>
+&lt;domainCapabilities&gt;
+  ...
+  &lt;os supported='yes'&gt;
+    &lt;loader supported='yes'&gt;
+      &lt;enum name='type'&gt;
+        &lt;value&gt;rom&lt;/value&gt;
+        &lt;value&gt;pflash&lt;/value&gt;
+      &lt;/enum&gt;
+      &lt;enum name='readonly'&gt;
+        &lt;value&gt;yes&lt;/value&gt;
+        &lt;value&gt;no&lt;/value&gt;
+      &lt;/enum&gt;
+    &lt;/loader&gt;
+  &lt;/os&gt;
+  ...
+&lt;domainCapabilities&gt;
+</pre>
+
+    <p>For the <code>loader</code> element, the following can occur:</p>
+
+    <dl>
+      <dt>type</dt>
+      <dd>Whether loader is a typical BIOS (<code>rom</code>) or
+      an UEFI binary (<code>pflash</code>). This refers to
+      <code>type</code> attribute of the &lt;loader/&gt;
+      element.</dd>
+
+      <dt>readonly</dt>
+      <dd>Options for the <code>readonly</code> attribute of the
+      &lt;loader/&gt; element.</dd>
+    </dl>
+
     <h3><a name="elementsDevices">Devices</a></h3>
 
     <p>

docs/schemas/domaincaps.rng

@@ -25,6 +25,9 @@
         <optional>
           <ref name='vcpu'/>
         </optional>
+        <optional>
+          <ref name='os'/>
+        </optional>
         <optional>
           <ref name='devices'/>
         </optional>
@@ -41,6 +44,24 @@
     </element>
   </define>
 
+  <define name='loader'>
+    <element name='loader'>
+      <ref name='supported'/>
+      <ref name='enum'/>
+    </element>
+  </define>
+
+  <define name='os'>
+    <element name='os'>
+      <interleave>
+        <ref name='supported'/>
+        <optional>
+          <ref name='loader'/>
+        </optional>
+      </interleave>
+    </element>
+  </define>
+
   <define name='devices'>
     <element name='devices'>
       <interleave>

src/conf/domain_capabilities.c

@@ -178,6 +178,32 @@ virDomainCapsEnumFormat(virBufferPtr buf,
                                 #capsEnum, valToStr);               \
     } while (0)
 
+
+static void
+virDomainCapsLoaderFormat(virBufferPtr buf,
+                          virDomainCapsLoaderPtr loader)
+{
+    FORMAT_PROLOGUE(loader);
+
+    ENUM_PROCESS(loader, type, virDomainLoaderTypeToString);
+    ENUM_PROCESS(loader, readonly, virTristateBoolTypeToString);
+
+    FORMAT_EPILOGUE(loader);
+}
+
+static void
+virDomainCapsOSFormat(virBufferPtr buf,
+                      virDomainCapsOSPtr os)
+{
+    virDomainCapsLoaderPtr loader = &os->loader;
+
+    FORMAT_PROLOGUE(os);
+
+    virDomainCapsLoaderFormat(buf, loader);
+
+    FORMAT_EPILOGUE(os);
+}
+
 static void
 virDomainCapsDeviceDiskFormat(virBufferPtr buf,
                               virDomainCapsDeviceDiskPtr const disk)
@@ -225,6 +251,8 @@ virDomainCapsFormatInternal(virBufferPtr buf,
     if (caps->maxvcpus)
         virBufferAsprintf(buf, "<vcpu max='%d'/>\n", caps->maxvcpus);
 
+    virDomainCapsOSFormat(buf, &caps->os);
+
     virBufferAddLit(buf, "<devices>\n");
     virBufferAdjustIndent(buf, 2);
 

src/conf/domain_capabilities.h

@@ -43,6 +43,21 @@ struct _virDomainCapsDevice {
     bool supported; /* true if <devtype> is supported by hypervisor */
 };
 
+typedef struct _virDomainCapsLoader virDomainCapsLoader;
+typedef virDomainCapsLoader *virDomainCapsLoaderPtr;
+struct _virDomainCapsLoader {
+    virDomainCapsDevice device;
+    virDomainCapsEnum type;     /* Info about virDomainLoader */
+    virDomainCapsEnum readonly; /* Info about readonly:virTristateBool */
+};
+
+typedef struct _virDomainCapsOS virDomainCapsOS;
+typedef virDomainCapsOS *virDomainCapsOSPtr;
+struct _virDomainCapsOS {
+    virDomainCapsDevice device;
+    virDomainCapsLoader loader;     /* Info about virDomainLoaderDef */
+};
+
 typedef struct _virDomainCapsDeviceDisk virDomainCapsDeviceDisk;
 typedef virDomainCapsDeviceDisk *virDomainCapsDeviceDiskPtr;
 struct _virDomainCapsDeviceDisk {
@@ -75,6 +90,7 @@ struct _virDomainCaps {
     /* Some machine specific info */
     int maxvcpus;
 
+    virDomainCapsOS os;
     virDomainCapsDeviceDisk disk;
     virDomainCapsDeviceHostdev hostdev;
     /* add new domain devices here */

src/qemu/qemu_capabilities.c

@@ -3608,6 +3608,42 @@ virQEMUCapsGetDefaultMachine(virQEMUCapsPtr qemuCaps)
 }
 
 
+static void
+virQEMUCapsFillDomainLoaderCaps(virQEMUCapsPtr qemuCaps,
+                                virDomainCapsLoaderPtr loader,
+                                virArch arch)
+{
+    loader->device.supported = true;
+
+    VIR_DOMAIN_CAPS_ENUM_SET(loader->type,
+                             VIR_DOMAIN_LOADER_TYPE_ROM);
+
+    if (arch == VIR_ARCH_X86_64 &&
+        virQEMUCapsGet(qemuCaps, QEMU_CAPS_DRIVE) &&
+        virQEMUCapsGet(qemuCaps, QEMU_CAPS_DRIVE_FORMAT))
+        VIR_DOMAIN_CAPS_ENUM_SET(loader->type,
+                                 VIR_DOMAIN_LOADER_TYPE_PFLASH);
+
+
+    if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_DRIVE_READONLY))
+        VIR_DOMAIN_CAPS_ENUM_SET(loader->readonly,
+                                 VIR_TRISTATE_BOOL_YES,
+                                 VIR_TRISTATE_BOOL_NO);
+}
+
+
+static void
+virQEMUCapsFillDomainOSCaps(virQEMUCapsPtr qemuCaps,
+                            virDomainCapsOSPtr os,
+                            virArch arch)
+{
+    virDomainCapsLoaderPtr loader = &os->loader;
+
+    os->device.supported = true;
+    virQEMUCapsFillDomainLoaderCaps(qemuCaps, loader, arch);
+}
+
+
 static void
 virQEMUCapsFillDomainDeviceDiskCaps(virQEMUCapsPtr qemuCaps,
                                     virDomainCapsDeviceDiskPtr disk)
@@ -3686,12 +3722,14 @@ void
 virQEMUCapsFillDomainCaps(virDomainCapsPtr domCaps,
                           virQEMUCapsPtr qemuCaps)
 {
+    virDomainCapsOSPtr os = &domCaps->os;
     virDomainCapsDeviceDiskPtr disk = &domCaps->disk;
     virDomainCapsDeviceHostdevPtr hostdev = &domCaps->hostdev;
     int maxvcpus = virQEMUCapsGetMachineMaxCpus(qemuCaps, domCaps->machine);
 
     domCaps->maxvcpus = maxvcpus;
 
+    virQEMUCapsFillDomainOSCaps(qemuCaps, os, domCaps->arch);
     virQEMUCapsFillDomainDeviceDiskCaps(qemuCaps, disk);
     virQEMUCapsFillDomainDeviceHostdevCaps(qemuCaps, hostdev);
 }

tests/domaincapsschemadata/domaincaps-basic.xml

@@ -3,6 +3,7 @@
   <domain>uml</domain>
   <machine>my-machine-type</machine>
   <arch>x86_64</arch>
+  <os supported='no'/>
   <devices>
     <disk supported='no'/>
     <hostdev supported='no'/>

tests/domaincapsschemadata/domaincaps-full.xml

@@ -4,6 +4,19 @@
   <machine>my-machine-type</machine>
   <arch>x86_64</arch>
   <vcpu max='255'/>
+  <os supported='yes'>
+    <loader supported='yes'>
+      <enum name='type'>
+        <value>rom</value>
+        <value>pflash</value>
+      </enum>
+      <enum name='readonly'>
+        <value>default</value>
+        <value>yes</value>
+        <value>no</value>
+      </enum>
+    </loader>
+  </os>
   <devices>
     <disk supported='yes'>
       <enum name='diskDevice'>

tests/domaincapsschemadata/domaincaps-qemu_1.6.50-1.xml

@@ -3,6 +3,18 @@
   <domain>kvm</domain>
   <machine>pc-1.2</machine>
   <arch>x86_64</arch>
+  <os supported='yes'>
+    <loader supported='yes'>
+      <enum name='type'>
+        <value>rom</value>
+        <value>pflash</value>
+      </enum>
+      <enum name='readonly'>
+        <value>yes</value>
+        <value>no</value>
+      </enum>
+    </loader>
+  </os>
   <devices>
     <disk supported='yes'>
       <enum name='diskDevice'>

tests/domaincapstest.c

@@ -38,10 +38,18 @@ static void
 fillAll(virDomainCapsPtr domCaps,
         void *opaque ATTRIBUTE_UNUSED)
 {
+    virDomainCapsOSPtr os = &domCaps->os;
+    virDomainCapsLoaderPtr loader = &os->loader;
     virDomainCapsDeviceDiskPtr disk = &domCaps->disk;
     virDomainCapsDeviceHostdevPtr hostdev = &domCaps->hostdev;
     domCaps->maxvcpus = 255;
 
+    os->device.supported = true;
+
+    loader->device.supported = true;
+    SET_ALL_BITS(loader->type);
+    SET_ALL_BITS(loader->readonly);
+
     disk->device.supported = true;
     SET_ALL_BITS(disk->diskDevice);
     SET_ALL_BITS(disk->bus);