1 files changed, 99 insertions, 0 deletions
diff --git a/include/system/confidential-guest-support.h b/include/system/confidential-guest-support.h
new file mode 100644
index 0000000000..b68c4bebbc
--- /dev/null
+++ b/include/system/confidential-guest-support.h
@@ -0,0 +1,99 @@
+/*
+ * QEMU Confidential Guest support
+ *   This interface describes the common pieces between various
+ *   schemes for protecting guest memory or other state against a
+ *   compromised hypervisor.  This includes memory encryption (AMD's
+ *   SEV and Intel's MKTME) or special protection modes (PEF on POWER,
+ *   or PV on s390x).
+ *
+ * Copyright Red Hat.
+ *
+ * Authors:
+ *  David Gibson <david@gibson.dropbear.id.au>
+ *
+ * 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 QEMU_CONFIDENTIAL_GUEST_SUPPORT_H
+#define QEMU_CONFIDENTIAL_GUEST_SUPPORT_H
+
+#ifdef CONFIG_USER_ONLY
+#error Cannot include system/confidential-guest-support.h from user emulation
+#endif
+
+#include "qom/object.h"
+
+#define TYPE_CONFIDENTIAL_GUEST_SUPPORT "confidential-guest-support"
+OBJECT_DECLARE_TYPE(ConfidentialGuestSupport,
+                    ConfidentialGuestSupportClass,
+                    CONFIDENTIAL_GUEST_SUPPORT)
+
+
+struct ConfidentialGuestSupport {
+    Object parent;
+
+    /*
+     * True if the machine should use guest_memfd for RAM.
+     */
+    bool require_guest_memfd;
+
+    /*
+     * ready: flag set by CGS initialization code once it's ready to
+     *        start executing instructions in a potentially-secure
+     *        guest
+     *
+     * The definition here is a bit fuzzy, because this is essentially
+     * part of a self-sanity-check, rather than a strict mechanism.
+     *
+     * It's not feasible to have a single point in the common machine
+     * init path to configure confidential guest support, because
+     * different mechanisms have different interdependencies requiring
+     * initialization in different places, often in arch or machine
+     * type specific code.  It's also usually not possible to check
+     * for invalid configurations until that initialization code.
+     * That means it would be very easy to have a bug allowing CGS
+     * init to be bypassed entirely in certain configurations.
+     *
+     * Silently ignoring a requested security feature would be bad, so
+     * to avoid that we check late in init that this 'ready' flag is
+     * set if CGS was requested.  If the CGS init hasn't happened, and
+     * so 'ready' is not set, we'll abort.
+     */
+    bool ready;
+};
+
+typedef struct ConfidentialGuestSupportClass {
+    ObjectClass parent;
+
+    int (*kvm_init)(ConfidentialGuestSupport *cgs, Error **errp);
+    int (*kvm_reset)(ConfidentialGuestSupport *cgs, Error **errp);
+} ConfidentialGuestSupportClass;
+
+static inline int confidential_guest_kvm_init(ConfidentialGuestSupport *cgs,
+                                              Error **errp)
+{
+    ConfidentialGuestSupportClass *klass;
+
+    klass = CONFIDENTIAL_GUEST_SUPPORT_GET_CLASS(cgs);
+    if (klass->kvm_init) {
+        return klass->kvm_init(cgs, errp);
+    }
+
+    return 0;
+}
+
+static inline int confidential_guest_kvm_reset(ConfidentialGuestSupport *cgs,
+                                               Error **errp)
+{
+    ConfidentialGuestSupportClass *klass;
+
+    klass = CONFIDENTIAL_GUEST_SUPPORT_GET_CLASS(cgs);
+    if (klass->kvm_reset) {
+        return klass->kvm_reset(cgs, errp);
+    }
+
+    return 0;
+}
+
+#endif /* QEMU_CONFIDENTIAL_GUEST_SUPPORT_H */