From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists1p.gnu.org (lists1p.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C530CC54F54 for ; Fri, 31 Jul 2026 11:43:49 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists1p.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1wple2-0007sp-Q9; Fri, 31 Jul 2026 07:43:18 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists1p.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wpldu-0007sB-49 for qemu-devel@nongnu.org; Fri, 31 Jul 2026 07:43:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1wplds-0007z1-D8 for qemu-devel@nongnu.org; Fri, 31 Jul 2026 07:43:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1785498186; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=nxuW/2r0U4Qe74Ikieml7ZXpyhkAlEPUGiAW1W1vJ54=; b=gQOE4+NLNELDIP6fdxxgQW47gM9HsaNdIswJB5HCS0n85zFyIxfyO5yYuVz2TTVcNCTz96 0P/VMD6NYPKingCR2ws3ntHVe/E14wjLF8cOdgNN65FJwow7SI4Z+3RK0dFRl5FI8idhOG /EXEsnZRW9dfeGjSKUp4WG2aqI+kNVE= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-82-jdphRHFEP1CvaRDFpPCKug-1; Fri, 31 Jul 2026 07:43:05 -0400 X-MC-Unique: jdphRHFEP1CvaRDFpPCKug-1 X-Mimecast-MFC-AGG-ID: jdphRHFEP1CvaRDFpPCKug_1785498184 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id BA7D31956089; Fri, 31 Jul 2026 11:43:03 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.44.22.4]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 3254219560AB; Fri, 31 Jul 2026 11:43:03 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id B873421E6920; Fri, 31 Jul 2026 13:43:00 +0200 (CEST) From: Markus Armbruster To: =?utf-8?Q?Marc-Andr=C3=A9?= Lureau Cc: qemu-devel@nongnu.org, Paolo Bonzini , Daniel P. =?utf-8?Q?Berrang=C3=A9?= , Michael Roth , Pierrick Bouvier , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= Subject: Re: [PATCH v2 01/53] qapi: add QAPITypeInfo struct definition In-Reply-To: <20260616-qom-qapi-v2-1-cc9396b9c18c@redhat.com> (=?utf-8?Q?=22Marc-Andr=C3=A9?= Lureau"'s message of "Tue, 16 Jun 2026 00:37:27 +0400") References: <20260616-qom-qapi-v2-0-cc9396b9c18c@redhat.com> <20260616-qom-qapi-v2-1-cc9396b9c18c@redhat.com> Date: Fri, 31 Jul 2026 13:43:00 +0200 Message-ID: <87mrv78jwb.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.133.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -2 X-Spam_score: -0.3 X-Spam_bar: / X-Spam_report: (-0.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.58, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Marc-Andr=C3=A9 Lureau writes: > Introduce a minimal struct that pairs a QAPI type's internal name with > its "masked" introspection name. Generated constants of this type will > let QOM property registration carry a reliable reference to the QAPI > schema and possibly other associated data. > > Signed-off-by: Marc-Andr=C3=A9 Lureau > --- > include/qapi/qapi-type-info.h | 32 ++++++++++++++++++++++++++++++++ > 1 file changed, 32 insertions(+) > > diff --git a/include/qapi/qapi-type-info.h b/include/qapi/qapi-type-info.h > new file mode 100644 > index 00000000000..a7a470af731 > --- /dev/null > +++ b/include/qapi/qapi-type-info.h > @@ -0,0 +1,32 @@ > +/* > + * SPDX-License-Identifier: GPL-2.0-or-later > + */ > + > +#ifndef QAPI_TYPE_INFO_H > +#define QAPI_TYPE_INFO_H > + > +#include "qapi/util.h" > + > +/** > + * QAPITypeInfo - QAPI type metadata > + * > + * @name: QAPI type name (e.g. "str", "OnOffAuto", "int32List"). > + * QOM uses this as the property type string. > + * @schema_name: Name of the type in the QAPI introspection schema, assi= gned by > + * scripts/qapi/introspect.py (e.g. "368"). NULL for builtin type= s not > + * individually present in the schema. "Schema" is ambiguous here: there's the QAPI schema (e.g. qapi/qapi-schema.json and its sub-modules), and the SchemaInfo returned by query-qmp-schema. Could well lead to confusion. What about @masked_name? > + * @lookup: QEnumLookup for this type, or NULL for non-enum types. > + * visit_type_enum(), qapi_enum_parse(), and qapi_enum_lookup() > + * all rely on it. Not yet. Either mention that in the commit message, or add the member later, when the comment is correct. > + * @list: The list-type counterpart, or NULL if none exists. > + * str_type_info.list points to strList_type_info. qdev array > + * properties follow this to find the list type for their element. Likewise. > + */ > +typedef struct QAPITypeInfo { > + const char *name; > + const char *schema_name; > + const QEnumLookup *lookup; > + const struct QAPITypeInfo *list; > +} QAPITypeInfo; > + > +#endif /* QAPI_TYPE_INFO_H */ This is somewhat related to SchemaInfo, which is also meta-data about QAPI types (and also commands and events). SchemaInfo only has the masked name[*]. It has a reference from array type to element type instead of the other way round. Everything else in QAPITypeInfo is also in SchemaInfo, I believe. So far, QEMU uses SchemaInfo only around qmp_query_qmp_schema(). qmp_query_qmp_schema() a SchemaInfoList on the fly from something else, and the QMP core (it's only caller) then converts it via QObject to a string reply. Now I need to digress into history a bit. The value of query-qmp-schema is fixed at compile time. My initial version simply generated the fixed reply as string. Efficient, because it doesn't build a (bulky!) QObject reply. Also a bit hacky. This got in the way of QAPI 'if' conditionals, so commit 7d0f982b switched to a pointer-less variation of the QObject that can be generated as data more easily: QLitObject[]. query-qmp-schema converts this to QObject every time it runs. The QLitObject[] would be awkward to use for anything else. End of digression. I wonder whether it could make sense to have a single repository of QAPI type meta data, usable both for query-qmp-schema and for your QOM work. Something QOM could use about as easily as QAPITypeInfo, and query-qmp-schema could convert to its reply. At this time, this is an idea phrased as a question. Is it a good idea? I'm not sure. Even if it is, I'm not sure it should be implemented right away. I'm just sharing the idea. [*] The QAPI generator has an option to make it have only the unmasked names. Occasionally convenient when messing around.