qemu: check for QEMU_CAPS_DEVICE_VHOST_VSOCK

My commit b8b42ca0 added support for formatting the vsock
command line without actually checking if it's supported.

Add it to the per-device validation function.

https://bugzilla.redhat.com/show_bug.cgi?id=1291851Reported-by: NJohn Ferlan <jferlan@redhat.com>
Signed-off-by: NJán Tomko <jtomko@redhat.com>
Reviewed-by: NJiri Denemark <jdenemar@redhat.com>

src/qemu/qemu_domain.c

@@ -5283,6 +5283,21 @@ qemuDomainDeviceDefValidateMemory(const virDomainMemoryDef *memory ATTRIBUTE_UNU
 }
 
 
+static int
+qemuDomainDeviceDefValidateVsock(const virDomainVsockDef *vsock ATTRIBUTE_UNUSED,
+                                 virQEMUCapsPtr qemuCaps)
+{
+    if (!virQEMUCapsGet(qemuCaps, QEMU_CAPS_DEVICE_VHOST_VSOCK)) {
+        virReportError(VIR_ERR_CONFIG_UNSUPPORTED, "%s",
+                       _("vsock device is not supported "
+                         "with this QEMU binary"));
+        return -1;
+    }
+
+    return 0;
+}
+
+
 static int
 qemuDomainDeviceDefValidate(const virDomainDeviceDef *dev,
                             const virDomainDef *def,
@@ -5342,6 +5357,10 @@ qemuDomainDeviceDefValidate(const virDomainDeviceDef *dev,
         ret = qemuDomainDeviceDefValidateMemory(dev->data.memory, def);
         break;
 
+    case VIR_DOMAIN_DEVICE_VSOCK:
+        ret = qemuDomainDeviceDefValidateVsock(dev->data.vsock, qemuCaps);
+        break;
+
     case VIR_DOMAIN_DEVICE_LEASE:
     case VIR_DOMAIN_DEVICE_FS:
     case VIR_DOMAIN_DEVICE_INPUT:
@@ -5354,7 +5373,6 @@ qemuDomainDeviceDefValidate(const virDomainDeviceDef *dev,
     case VIR_DOMAIN_DEVICE_TPM:
     case VIR_DOMAIN_DEVICE_PANIC:
     case VIR_DOMAIN_DEVICE_IOMMU:
-    case VIR_DOMAIN_DEVICE_VSOCK:
     case VIR_DOMAIN_DEVICE_NONE:
     case VIR_DOMAIN_DEVICE_LAST:
         break;

tests/qemuxml2xmltest.c

@@ -1212,8 +1212,8 @@ mymain(void)
     DO_TEST_STATUS("migration-out-params");
     DO_TEST_STATUS("migration-out-nbd-tls");
 
-    DO_TEST("vhost-vsock", NONE);
-    DO_TEST("vhost-vsock-auto", NONE);
+    DO_TEST("vhost-vsock", QEMU_CAPS_DEVICE_VHOST_VSOCK);
+    DO_TEST("vhost-vsock-auto", QEMU_CAPS_DEVICE_VHOST_VSOCK);
 
     if (getenv("LIBVIRT_SKIP_CLEANUP") == NULL)
         virFileDeleteTree(fakerootdir);