[PULL 05/25] qapi: Convert simple union TpmTypeOptions to flat one

[Markus Armbruster <armbru@redhat.com>]

Simple unions predate flat unions.  Having both complicates the QAPI
schema language and the QAPI generator.  We haven't been using simple
unions in new code for a long time, because they are less flexible and
somewhat awkward on the wire.

To prepare for their removal, convert simple union TpmTypeOptions to
an equivalent flat one, with existing enum TpmType replacing implicit
enum TpmTypeOptionsKind.  Adds some boilerplate to the schema, which
is a bit ugly, but a lot easier to maintain than the simple union
feature.

Cc: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Acked-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20210917143134.412106-6-armbru@redhat.com>
---
 qapi/tpm.json                  | 24 ++++++++++++++++++++++--
 backends/tpm/tpm_emulator.c    |  2 +-
 backends/tpm/tpm_passthrough.c |  2 +-
 monitor/hmp-cmds.c             |  8 ++++----
 4 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/qapi/tpm.json b/qapi/tpm.json
index f4dde2f646..3e7669facf 100644
--- a/qapi/tpm.json
+++ b/qapi/tpm.json
@@ -99,6 +99,24 @@
 { 'struct': 'TPMEmulatorOptions', 'data': { 'chardev' : 'str' },
   'if': 'CONFIG_TPM' }
 
+##
+# @TPMPassthroughOptionsWrapper:
+#
+# Since: 1.5
+##
+{ 'struct': 'TPMPassthroughOptionsWrapper',
+  'data': { 'data': 'TPMPassthroughOptions' },
+  'if': 'CONFIG_TPM' }
+
+##
+# @TPMEmulatorOptionsWrapper:
+#
+# Since: 2.11
+##
+{ 'struct': 'TPMEmulatorOptionsWrapper',
+  'data': { 'data': 'TPMEmulatorOptions' },
+  'if': 'CONFIG_TPM' }
+
 ##
 # @TpmTypeOptions:
 #
@@ -110,8 +128,10 @@
 # Since: 1.5
 ##
 { 'union': 'TpmTypeOptions',
-   'data': { 'passthrough' : 'TPMPassthroughOptions',
-             'emulator': 'TPMEmulatorOptions' },
+  'base': { 'type': 'TpmType' },
+  'discriminator': 'type',
+   'data': { 'passthrough' : 'TPMPassthroughOptionsWrapper',
+             'emulator': 'TPMEmulatorOptionsWrapper' },
   'if': 'CONFIG_TPM' }
 
 ##
diff --git a/backends/tpm/tpm_emulator.c b/backends/tpm/tpm_emulator.c
index f8095d23d5..87d061e9bb 100644
--- a/backends/tpm/tpm_emulator.c
+++ b/backends/tpm/tpm_emulator.c
@@ -623,7 +623,7 @@ static TpmTypeOptions *tpm_emulator_get_tpm_options(TPMBackend *tb)
     TPMEmulator *tpm_emu = TPM_EMULATOR(tb);
     TpmTypeOptions *options = g_new0(TpmTypeOptions, 1);
 
-    options->type = TPM_TYPE_OPTIONS_KIND_EMULATOR;
+    options->type = TPM_TYPE_EMULATOR;
     options->u.emulator.data = QAPI_CLONE(TPMEmulatorOptions, tpm_emu->options);
 
     return options;
diff --git a/backends/tpm/tpm_passthrough.c b/backends/tpm/tpm_passthrough.c
index 21b7459183..d5558fae6c 100644
--- a/backends/tpm/tpm_passthrough.c
+++ b/backends/tpm/tpm_passthrough.c
@@ -321,7 +321,7 @@ static TpmTypeOptions *tpm_passthrough_get_tpm_options(TPMBackend *tb)
 {
     TpmTypeOptions *options = g_new0(TpmTypeOptions, 1);
 
-    options->type = TPM_TYPE_OPTIONS_KIND_PASSTHROUGH;
+    options->type = TPM_TYPE_PASSTHROUGH;
     options->u.passthrough.data = QAPI_CLONE(TPMPassthroughOptions,
                                              TPM_PASSTHROUGH(tb)->options);
 
diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index e00255f7ee..d6858407ad 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -925,10 +925,10 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
                        c, TpmModel_str(ti->model));
 
         monitor_printf(mon, "  \\ %s: type=%s",
-                       ti->id, TpmTypeOptionsKind_str(ti->options->type));
+                       ti->id, TpmType_str(ti->options->type));
 
         switch (ti->options->type) {
-        case TPM_TYPE_OPTIONS_KIND_PASSTHROUGH:
+        case TPM_TYPE_PASSTHROUGH:
             tpo = ti->options->u.passthrough.data;
             monitor_printf(mon, "%s%s%s%s",
                            tpo->has_path ? ",path=" : "",
@@ -936,11 +936,11 @@ void hmp_info_tpm(Monitor *mon, const QDict *qdict)
                            tpo->has_cancel_path ? ",cancel-path=" : "",
                            tpo->has_cancel_path ? tpo->cancel_path : "");
             break;
-        case TPM_TYPE_OPTIONS_KIND_EMULATOR:
+        case TPM_TYPE_EMULATOR:
             teo = ti->options->u.emulator.data;
             monitor_printf(mon, ",chardev=%s", teo->chardev);
             break;
-        case TPM_TYPE_OPTIONS_KIND__MAX:
+        case TPM_TYPE__MAX:
             break;
         }
         monitor_printf(mon, "\n");
-- 
2.31.1