[libvirt PATCH] xenconfig: Add feature gfx_passthru

[Artur Puzio]

gfx_passthru xl.cfg option enables GPU specific quirks required for working
Intel GPU passthru. Qemu (used for device model by xen) will refuse to start
a VM when an IGD is passed, but this option was not set in Xen.

Signed-off-by: Artur Puzio <contact at puzio.waw.pl>
---
 docs/formatdomain.html.in     |  7 +++++++
 docs/schemas/domaincommon.rng |  5 +++++
 src/conf/domain_conf.c        |  4 ++++
 src/conf/domain_conf.h        |  1 +
 src/libxl/libxl_conf.c        | 13 +++++++++++++
 5 files changed, 30 insertions(+)

diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index 91d6f6c0d3..5307844a23 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -2064,6 +2064,7 @@
   <xen>
     <e820_host state='on'/>
     <passthrough state='on' mode='share_pt'/>
+    <gfx_passthru state='on'/>
   </xen>
   <pvspinlock state='on'/>
   <gic version='2'/>
@@ -2270,6 +2271,12 @@
           <td>on, off; mode - optional string sync_pt or share_pt</td>
           <td><span class="since">6.3.0</span></td>
         </tr>
+        <tr>
+          <td>gfx_passthru</td>
+          <td>Enable Intel GPU specific quirks. Required and allowed only when passing an IGD.</td>
+          <td>on, off</td>
+          <td><span class="since">6.3.0</span></td>
+        </tr>
       </table>
       </dd>
       <dt><code>pmu</code></dt>
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index 9d60b090f3..7d8ea879a1 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -6409,6 +6409,11 @@
             </optional>
           </element>
         </optional>
+        <optional>
+          <element name="gfx_passthru">
+            <ref name="featurestate"/>
+          </element>
+        </optional>
       </interleave>
     </element>
   </define>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 8a87586936..75f72ff64c 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -214,6 +214,7 @@ VIR_ENUM_IMPL(virDomainXen,
               VIR_DOMAIN_XEN_LAST,
               "e820_host",
               "passthrough",
+              "gfx_passthru"
 );
 
 VIR_ENUM_IMPL(virDomainXenPassthroughMode,
@@ -19649,6 +19650,7 @@ virDomainFeaturesDefParse(virDomainDefPtr def,
 
             switch ((virDomainXen) feature) {
                 case VIR_DOMAIN_XEN_E820_HOST:
+                case VIR_DOMAIN_XEN_GFX_PASSTHRU:
                     break;
 
             case VIR_DOMAIN_XEN_PASSTHROUGH:
@@ -23579,6 +23581,7 @@ virDomainDefFeaturesCheckABIStability(virDomainDefPtr src,
             }
             switch ((virDomainXen) i) {
             case VIR_DOMAIN_XEN_E820_HOST:
+            case VIR_DOMAIN_XEN_GFX_PASSTHRU:
                 break;
 
             case VIR_DOMAIN_XEN_PASSTHROUGH:
@@ -29235,6 +29238,7 @@ virDomainDefFormatFeatures(virBufferPtr buf,
 
                 switch ((virDomainXen) j) {
                 case VIR_DOMAIN_XEN_E820_HOST:
+                case VIR_DOMAIN_XEN_GFX_PASSTHRU:
                     virBufferAddLit(&childBuf, "/>\n");
                     break;
                 case VIR_DOMAIN_XEN_PASSTHROUGH:
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 4afd8f04bc..f28f0741ac 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -1867,6 +1867,7 @@ typedef enum {
 typedef enum {
     VIR_DOMAIN_XEN_E820_HOST = 0,
     VIR_DOMAIN_XEN_PASSTHROUGH,
+    VIR_DOMAIN_XEN_GFX_PASSTHRU,
 
     VIR_DOMAIN_XEN_LAST
 } virDomainXen;
diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c
index 458dfc2399..a5605f6200 100644
--- a/src/libxl/libxl_conf.c
+++ b/src/libxl/libxl_conf.c
@@ -679,6 +679,19 @@ libxlMakeDomBuildInfo(virDomainDefPtr def,
             return -1;
         }
 #endif
+        if (def->features[VIR_DOMAIN_FEATURE_XEN] == VIR_TRISTATE_SWITCH_ON) {
+            switch ((virTristateSwitch) def->xen_features[VIR_DOMAIN_XEN_GFX_PASSTHRU]) {
+                case VIR_TRISTATE_SWITCH_ON:
+                    libxl_defbool_set(&b_info->u.hvm.gfx_passthru, true);
+                    break;
+                case VIR_TRISTATE_SWITCH_OFF:
+                    libxl_defbool_set(&b_info->u.hvm.gfx_passthru, false);
+                    break;
+                case VIR_TRISTATE_SWITCH_ABSENT:
+                case VIR_TRISTATE_SWITCH_LAST:
+                    break;
+            }
+        }
     } else if (pvh) {
         b_info->cmdline = g_strdup(def->os.cmdline);
         b_info->kernel = g_strdup(def->os.kernel);
-- 
2.26.2