qapi migration: Elide redundant has_FOO in generated C

The has_FOO for pointer-valued FOO are redundant, except for arrays.
They are also a nuisance to work with.  Recent commit "qapi: Start to
elide redundant has_FOO in generated C" provided the means to elide
them step by step.  This is the step for qapi/migration.json.

Said commit explains the transformation in more detail.  The invariant
violations mentioned there do not occur here.

Cc: Juan Quintela <quintela@redhat.com>
Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221018062849.3420573-15-armbru@redhat.com>

migration/block-dirty-bitmap.c

@@ -551,7 +551,7 @@ static int add_bitmaps_to_list(DBMSaveState *s, BlockDriverState *bs,
             }
 
             bitmap_alias = bmap_inner->alias;
-            if (bmap_inner->has_transform) {
+            if (bmap_inner->transform) {
                 bitmap_transform = bmap_inner->transform;
             }
         } else {
@@ -821,7 +821,7 @@ static int dirty_bitmap_load_start(QEMUFile *f, DBMLoadState *s)
     }
 
     if (s->bmap_inner &&
-        s->bmap_inner->has_transform &&
+        s->bmap_inner->transform &&
         s->bmap_inner->transform->has_persistent) {
         persistent = s->bmap_inner->transform->persistent;
     } else {

migration/colo.c

@@ -250,7 +250,6 @@ ReplicationStatus *qmp_query_xen_replication_status(Error **errp)
     replication_get_error_all(&err);
     if (err) {
         s->error = true;
-        s->has_desc = true;
         s->desc = g_strdup(error_get_pretty(err));
     } else {
         s->error = false;

migration/migration.c

@@ -918,11 +918,8 @@ MigrationParameters *qmp_query_migrate_parameters(Error **errp)
     params->cpu_throttle_increment = s->parameters.cpu_throttle_increment;
     params->has_cpu_throttle_tailslow = true;
     params->cpu_throttle_tailslow = s->parameters.cpu_throttle_tailslow;
-    params->has_tls_creds = true;
     params->tls_creds = g_strdup(s->parameters.tls_creds);
-    params->has_tls_hostname = true;
     params->tls_hostname = g_strdup(s->parameters.tls_hostname);
-    params->has_tls_authz = true;
     params->tls_authz = g_strdup(s->parameters.tls_authz ?
                                  s->parameters.tls_authz : "");
     params->has_max_bandwidth = true;
@@ -1047,7 +1044,6 @@ static void populate_ram_info(MigrationInfo *info, MigrationState *s)
 {
     size_t page_size = qemu_target_page_size();
 
-    info->has_ram = true;
     info->ram = g_malloc0(sizeof(*info->ram));
     info->ram->transferred = ram_counters.transferred;
     info->ram->total = ram_bytes_total();
@@ -1069,7 +1065,6 @@ static void populate_ram_info(MigrationInfo *info, MigrationState *s)
     info->ram->postcopy_bytes = ram_counters.postcopy_bytes;
 
     if (migrate_use_xbzrle()) {
-        info->has_xbzrle_cache = true;
         info->xbzrle_cache = g_malloc0(sizeof(*info->xbzrle_cache));
         info->xbzrle_cache->cache_size = migrate_xbzrle_cache_size();
         info->xbzrle_cache->bytes = xbzrle_counters.bytes;
@@ -1081,7 +1076,6 @@ static void populate_ram_info(MigrationInfo *info, MigrationState *s)
     }
 
     if (migrate_use_compression()) {
-        info->has_compression = true;
         info->compression = g_malloc0(sizeof(*info->compression));
         info->compression->pages = compression_counters.pages;
         info->compression->busy = compression_counters.busy;
@@ -1106,7 +1100,6 @@ static void populate_ram_info(MigrationInfo *info, MigrationState *s)
 static void populate_disk_info(MigrationInfo *info)
 {
     if (blk_mig_active()) {
-        info->has_disk = true;
         info->disk = g_malloc0(sizeof(*info->disk));
         info->disk->transferred = blk_mig_bytes_transferred();
         info->disk->remaining = blk_mig_bytes_remaining();
@@ -1171,7 +1164,6 @@ static void fill_source_migration_info(MigrationInfo *info)
     case MIGRATION_STATUS_FAILED:
         info->has_status = true;
         if (s->error) {
-            info->has_error_desc = true;
             info->error_desc = g_strdup(error_get_pretty(s->error));
         }
         break;
@@ -1557,7 +1549,7 @@ static bool migrate_params_check(MigrationParameters *params, Error **errp)
 #ifdef CONFIG_LINUX
     if (migrate_use_zero_copy_send() &&
         ((params->has_multifd_compression && params->multifd_compression) ||
-         (params->has_tls_creds && params->tls_creds && *params->tls_creds))) {
+         (params->tls_creds && *params->tls_creds))) {
         error_setg(errp,
                    "Zero copy only available for non-compressed non-TLS multifd migration");
         return false;
@@ -1606,12 +1598,12 @@ static void migrate_params_test_apply(MigrateSetParameters *params,
         dest->cpu_throttle_tailslow = params->cpu_throttle_tailslow;
     }
 
-    if (params->has_tls_creds) {
+    if (params->tls_creds) {
         assert(params->tls_creds->type == QTYPE_QSTRING);
         dest->tls_creds = params->tls_creds->u.s;
     }
 
-    if (params->has_tls_hostname) {
+    if (params->tls_hostname) {
         assert(params->tls_hostname->type == QTYPE_QSTRING);
         dest->tls_hostname = params->tls_hostname->u.s;
     }
@@ -1703,19 +1695,19 @@ static void migrate_params_apply(MigrateSetParameters *params, Error **errp)
         s->parameters.cpu_throttle_tailslow = params->cpu_throttle_tailslow;
     }
 
-    if (params->has_tls_creds) {
+    if (params->tls_creds) {
         g_free(s->parameters.tls_creds);
         assert(params->tls_creds->type == QTYPE_QSTRING);
         s->parameters.tls_creds = g_strdup(params->tls_creds->u.s);
     }
 
-    if (params->has_tls_hostname) {
+    if (params->tls_hostname) {
         g_free(s->parameters.tls_hostname);
         assert(params->tls_hostname->type == QTYPE_QSTRING);
         s->parameters.tls_hostname = g_strdup(params->tls_hostname->u.s);
     }
 
-    if (params->has_tls_authz) {
+    if (params->tls_authz) {
         g_free(s->parameters.tls_authz);
         assert(params->tls_authz->type == QTYPE_QSTRING);
         s->parameters.tls_authz = g_strdup(params->tls_authz->u.s);
@@ -1792,14 +1784,14 @@ void qmp_migrate_set_parameters(MigrateSetParameters *params, Error **errp)
     MigrationParameters tmp;
 
     /* TODO Rewrite "" to null instead */
-    if (params->has_tls_creds
+    if (params->tls_creds
         && params->tls_creds->type == QTYPE_QNULL) {
         qobject_unref(params->tls_creds->u.n);
         params->tls_creds->type = QTYPE_QSTRING;
         params->tls_creds->u.s = strdup("");
     }
     /* TODO Rewrite "" to null instead */
-    if (params->has_tls_hostname
+    if (params->tls_hostname
         && params->tls_hostname->type == QTYPE_QNULL) {
         qobject_unref(params->tls_hostname->u.n);
         params->tls_hostname->type = QTYPE_QSTRING;
@@ -4474,9 +4466,6 @@ static void migration_instance_init(Object *obj)
     params->has_announce_max = true;
     params->has_announce_rounds = true;
     params->has_announce_step = true;
-    params->has_tls_creds = true;
-    params->has_tls_hostname = true;
-    params->has_tls_authz = true;
 
     qemu_sem_init(&ms->postcopy_pause_sem, 0);
     qemu_sem_init(&ms->postcopy_pause_rp_sem, 0);

monitor/hmp-cmds.c

@@ -240,8 +240,7 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
     if (info->has_status) {
         monitor_printf(mon, "Migration status: %s",
                        MigrationStatus_str(info->status));
-        if (info->status == MIGRATION_STATUS_FAILED &&
-            info->has_error_desc) {
+        if (info->status == MIGRATION_STATUS_FAILED && info->error_desc) {
             monitor_printf(mon, " (%s)\n", info->error_desc);
         } else {
             monitor_printf(mon, "\n");
@@ -263,7 +262,7 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
         }
     }
 
-    if (info->has_ram) {
+    if (info->ram) {
         monitor_printf(mon, "transferred ram: %" PRIu64 " kbytes\n",
                        info->ram->transferred >> 10);
         monitor_printf(mon, "throughput: %0.2f mbps\n",
@@ -316,7 +315,7 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
         }
     }
 
-    if (info->has_disk) {
+    if (info->disk) {
         monitor_printf(mon, "transferred disk: %" PRIu64 " kbytes\n",
                        info->disk->transferred >> 10);
         monitor_printf(mon, "remaining disk: %" PRIu64 " kbytes\n",
@@ -325,7 +324,7 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
                        info->disk->total >> 10);
     }
 
-    if (info->has_xbzrle_cache) {
+    if (info->xbzrle_cache) {
         monitor_printf(mon, "cache size: %" PRIu64 " bytes\n",
                        info->xbzrle_cache->cache_size);
         monitor_printf(mon, "xbzrle transferred: %" PRIu64 " kbytes\n",
@@ -342,7 +341,7 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
                        info->xbzrle_cache->overflow);
     }
 
-    if (info->has_compression) {
+    if (info->compression) {
         monitor_printf(mon, "compression pages: %" PRIu64 " pages\n",
                        info->compression->pages);
         monitor_printf(mon, "compression busy: %" PRIu64 "\n",
@@ -389,7 +388,7 @@ void hmp_info_migrate(Monitor *mon, const QDict *qdict)
         monitor_printf(mon, "]\n");
     }
 
-    if (info->has_vfio) {
+    if (info->vfio) {
         monitor_printf(mon, "vfio device transferred: %" PRIu64 " kbytes\n",
                        info->vfio->transferred >> 10);
     }
@@ -469,11 +468,11 @@ void hmp_info_migrate_parameters(Monitor *mon, const QDict *qdict)
         monitor_printf(mon, "%s: %u\n",
             MigrationParameter_str(MIGRATION_PARAMETER_MAX_CPU_THROTTLE),
             params->max_cpu_throttle);
-        assert(params->has_tls_creds);
+        assert(params->tls_creds);
         monitor_printf(mon, "%s: '%s'\n",
             MigrationParameter_str(MIGRATION_PARAMETER_TLS_CREDS),
             params->tls_creds);
-        assert(params->has_tls_hostname);
+        assert(params->tls_hostname);
         monitor_printf(mon, "%s: '%s'\n",
             MigrationParameter_str(MIGRATION_PARAMETER_TLS_HOSTNAME),
             params->tls_hostname);
@@ -1258,19 +1257,16 @@ void hmp_migrate_set_parameter(Monitor *mon, const QDict *qdict)
         visit_type_uint8(v, param, &p->max_cpu_throttle, &err);
         break;
     case MIGRATION_PARAMETER_TLS_CREDS:
-        p->has_tls_creds = true;
         p->tls_creds = g_new0(StrOrNull, 1);
         p->tls_creds->type = QTYPE_QSTRING;
         visit_type_str(v, param, &p->tls_creds->u.s, &err);
         break;
     case MIGRATION_PARAMETER_TLS_HOSTNAME:
-        p->has_tls_hostname = true;
         p->tls_hostname = g_new0(StrOrNull, 1);
         p->tls_hostname->type = QTYPE_QSTRING;
         visit_type_str(v, param, &p->tls_hostname->u.s, &err);
         break;
     case MIGRATION_PARAMETER_TLS_AUTHZ:
-        p->has_tls_authz = true;
         p->tls_authz = g_new0(StrOrNull, 1);
         p->tls_authz->type = QTYPE_QSTRING;
         visit_type_str(v, param, &p->tls_authz->u.s, &err);
@@ -1382,7 +1378,7 @@ void hmp_client_migrate_info(Monitor *mon, const QDict *qdict)
 
     qmp_client_migrate_info(protocol, hostname,
                             has_port, port, has_tls_port, tls_port,
-                            !!cert_subject, cert_subject, &err);
+                            cert_subject, &err);
     hmp_handle_error(mon, err);
 }
 
@@ -1540,7 +1536,7 @@ static void hmp_migrate_status_cb(void *opaque)
     info = qmp_query_migrate(NULL);
     if (!info->has_status || info->status == MIGRATION_STATUS_ACTIVE ||
         info->status == MIGRATION_STATUS_SETUP) {
-        if (info->has_disk) {
+        if (info->disk) {
             int progress;
 
             if (info->disk->remaining) {
@@ -1558,7 +1554,7 @@ static void hmp_migrate_status_cb(void *opaque)
         if (status->is_block_migration) {
             monitor_printf(status->mon, "\n");
         }
-        if (info->has_error_desc) {
+        if (info->error_desc) {
             error_report("%s", info->error_desc);
         }
         monitor_resume(status->mon);

monitor/misc.c

@@ -398,7 +398,7 @@ static void hmp_info_trace_events(Monitor *mon, const QDict *qdict)
 void qmp_client_migrate_info(const char *protocol, const char *hostname,
                              bool has_port, int64_t port,
                              bool has_tls_port, int64_t tls_port,
-                             bool has_cert_subject, const char *cert_subject,
+                             const char *cert_subject,
                              Error **errp)
 {
     if (strcmp(protocol, "spice") == 0) {

scripts/qapi/schema.py

@@ -759,7 +759,6 @@ def need_has(self):
         assert self.type
         # Temporary hack to support dropping the has_FOO in reviewable chunks
         opt_out = [
-            'qapi/migration.json',
             'qapi/misc.json',
             'qapi/net.json',
             'qapi/pci.json',