target/i386: introduce x86-confidential-guest

Introduce a common superclass for x86 confidential guest implementations.
It will extend ConfidentialGuestSupportClass with a method that provides
the VM type to be passed to KVM_CREATE_VM.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

target/i386/confidential-guest.c

@@ -0,0 +1,33 @@
+/*
+ * QEMU Confidential Guest support
+ *
+ * Copyright (C) 2024 Red Hat, Inc.
+ *
+ * Authors:
+ *  Paolo Bonzini <pbonzini@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later.  See the COPYING file in the top-level directory.
+ *
+ */
+
+#include "qemu/osdep.h"
+
+#include "confidential-guest.h"
+
+OBJECT_DEFINE_ABSTRACT_TYPE(X86ConfidentialGuest,
+                            x86_confidential_guest,
+                            X86_CONFIDENTIAL_GUEST,
+                            CONFIDENTIAL_GUEST_SUPPORT)
+
+static void x86_confidential_guest_class_init(ObjectClass *oc, void *data)
+{
+}
+
+static void x86_confidential_guest_init(Object *obj)
+{
+}
+
+static void x86_confidential_guest_finalize(Object *obj)
+{
+}

target/i386/confidential-guest.h

@@ -0,0 +1,40 @@
+/*
+ * x86-specific confidential guest methods.
+ *
+ * Copyright (c) 2024 Red Hat Inc.
+ *
+ * Authors:
+ *  Paolo Bonzini <pbonzini@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+#ifndef TARGET_I386_CG_H
+#define TARGET_I386_CG_H
+
+#include "qom/object.h"
+
+#include "exec/confidential-guest-support.h"
+
+#define TYPE_X86_CONFIDENTIAL_GUEST "x86-confidential-guest"
+
+OBJECT_DECLARE_TYPE(X86ConfidentialGuest,
+                    X86ConfidentialGuestClass,
+                    X86_CONFIDENTIAL_GUEST)
+
+struct X86ConfidentialGuest {
+    /* <private> */
+    ConfidentialGuestSupport parent_obj;
+};
+
+/**
+ * X86ConfidentialGuestClass:
+ *
+ * Class to be implemented by confidential-guest-support concrete objects
+ * for the x86 target.
+ */
+struct X86ConfidentialGuestClass {
+    /* <private> */
+    ConfidentialGuestSupportClass parent;
+};
+#endif

target/i386/meson.build

@@ -6,7 +6,7 @@ i386_ss.add(files(
   'xsave_helper.c',
   'cpu-dump.c',
 ))
-i386_ss.add(when: 'CONFIG_SEV', if_true: files('host-cpu.c'))
+i386_ss.add(when: 'CONFIG_SEV', if_true: files('host-cpu.c', 'confidential-guest.c'))
 
 # x86 cpu type
 i386_ss.add(when: 'CONFIG_KVM', if_true: files('host-cpu.c'))

target/i386/sev.c

@@ -35,7 +35,7 @@
 #include "monitor/monitor.h"
 #include "monitor/hmp-target.h"
 #include "qapi/qapi-commands-misc-target.h"
-#include "exec/confidential-guest-support.h"
+#include "confidential-guest.h"
 #include "hw/i386/pc.h"
 #include "exec/address-spaces.h"
 
@@ -54,7 +54,7 @@ OBJECT_DECLARE_SIMPLE_TYPE(SevGuestState, SEV_GUEST)
  *         -machine ...,memory-encryption=sev0
  */
 struct SevGuestState {
-    ConfidentialGuestSupport parent_obj;
+    X86ConfidentialGuest parent_obj;
 
     /* configuration parameters */
     char *sev_device;
@@ -1372,7 +1372,7 @@ sev_guest_instance_init(Object *obj)
 
 /* sev guest info */
 static const TypeInfo sev_guest_info = {
-    .parent = TYPE_CONFIDENTIAL_GUEST_SUPPORT,
+    .parent = TYPE_X86_CONFIDENTIAL_GUEST,
     .name = TYPE_SEV_GUEST,
     .instance_size = sizeof(SevGuestState),
     .instance_finalize = sev_guest_finalize,