Add UserCreatableClass->complete callback function for igvm-cfg object.

Move file loading and parsing of the igvm file from the process function
to the new complete() callback function.  Keep the igvm file loaded
after processing, release it in finalize() instead, so we parse it only
once.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Ani Sinha <anisinha@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
---
 include/system/igvm-internal.h |  5 +++++
 backends/igvm-cfg.c            | 18 ++++++++++++++++++
 backends/igvm.c                |  9 ++++-----
 3 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/include/system/igvm-internal.h b/include/system/igvm-internal.h
index ac9e5683cc63..171cec8d0f6c 100644
--- a/include/system/igvm-internal.h
+++ b/include/system/igvm-internal.h
@@ -13,6 +13,8 @@
 #include "qom/object.h"
 #include "hw/core/resettable.h"
 
+#include <igvm/igvm.h>
+
 struct IgvmCfg {
     ObjectClass parent_class;
 
@@ -22,7 +24,10 @@ struct IgvmCfg {
      *           format.
      */
     char *filename;
+    IgvmHandle file;
     ResettableState reset_state;
 };
 
+IgvmHandle qigvm_file_init(char *filename, Error **errp);
+
 #endif
diff --git a/backends/igvm-cfg.c b/backends/igvm-cfg.c
index e0df3eaa8efd..4014062e0f22 100644
--- a/backends/igvm-cfg.c
+++ b/backends/igvm-cfg.c
@@ -53,6 +53,13 @@ static void igvm_reset_exit(Object *obj, ResetType type)
     trace_igvm_reset_exit(type);
 }
 
+static void igvm_complete(UserCreatable *uc, Error **errp)
+{
+    IgvmCfg *igvm = IGVM_CFG(uc);
+
+    igvm->file = qigvm_file_init(igvm->filename, errp);
+}
+
 OBJECT_DEFINE_TYPE_WITH_INTERFACES(IgvmCfg, igvm_cfg, IGVM_CFG, OBJECT,
                                    { TYPE_USER_CREATABLE },
                                    { TYPE_RESETTABLE_INTERFACE },
@@ -62,6 +69,7 @@ static void igvm_cfg_class_init(ObjectClass *oc, const void *data)
 {
     IgvmCfgClass *igvmc = IGVM_CFG_CLASS(oc);
     ResettableClass *rc = RESETTABLE_CLASS(oc);
+    UserCreatableClass *uc = USER_CREATABLE_CLASS(oc);
 
     object_class_property_add_str(oc, "file", get_igvm, set_igvm);
     object_class_property_set_description(oc, "file",
@@ -73,14 +81,24 @@ static void igvm_cfg_class_init(ObjectClass *oc, const void *data)
     rc->phases.enter = igvm_reset_enter;
     rc->phases.hold = igvm_reset_hold;
     rc->phases.exit = igvm_reset_exit;
+
+    uc->complete = igvm_complete;
 }
 
 static void igvm_cfg_init(Object *obj)
 {
+    IgvmCfg *igvm = IGVM_CFG(obj);
+
+    igvm->file = -1;
     qemu_register_resettable(obj);
 }
 
 static void igvm_cfg_finalize(Object *obj)
 {
+    IgvmCfg *igvm = IGVM_CFG(obj);
+
     qemu_unregister_resettable(obj);
+    if (igvm->file >= 0) {
+        igvm_free(igvm->file);
+    }
 }
diff --git a/backends/igvm.c b/backends/igvm.c
index fbb8300b6d01..a01e01a12a60 100644
--- a/backends/igvm.c
+++ b/backends/igvm.c
@@ -869,7 +869,7 @@ static int qigvm_handle_policy(QIgvm *ctx, Error **errp)
     return 0;
 }
 
-static IgvmHandle qigvm_file_init(char *filename, Error **errp)
+IgvmHandle qigvm_file_init(char *filename, Error **errp)
 {
     IgvmHandle igvm;
     g_autofree uint8_t *buf = NULL;
@@ -898,10 +898,11 @@ int qigvm_process_file(IgvmCfg *cfg, ConfidentialGuestSupport *cgs,
     QIgvm ctx;
 
     memset(&ctx, 0, sizeof(ctx));
-    ctx.file = qigvm_file_init(cfg->filename, errp);
-    if (ctx.file < 0) {
+    if (cfg->file < 0) {
+        error_setg(errp, "No IGVM file loaded.");
         return -1;
     }
+    ctx.file = cfg->file;
 
     /*
      * The ConfidentialGuestSupport object is optional and allows a confidential
@@ -992,7 +993,5 @@ cleanup_parameters:
     g_free(ctx.id_auth);
 
 cleanup:
-    igvm_free(ctx.file);
-
     return retval;
 }
-- 
2.52.0