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 X-Spam-Level: X-Spam-Status: No, score=-3.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8322DC2D0A3 for ; Thu, 29 Oct 2020 12:58:59 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id AE85420720 for ; Thu, 29 Oct 2020 12:58:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="fjLxwCfJ" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AE85420720 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:37100 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kY7W4-0000Vv-Id for qemu-devel@archiver.kernel.org; Thu, 29 Oct 2020 08:58:57 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60940) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kY7U4-00083d-RG for qemu-devel@nongnu.org; Thu, 29 Oct 2020 08:56:52 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:41981) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kY7Tx-0005rH-Ga for qemu-devel@nongnu.org; Thu, 29 Oct 2020 08:56:52 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1603976201; 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: in-reply-to:in-reply-to:references:references; bh=FrI5W+01vRkkKOyxipHwmwMgkj+pAmPgaDpp5Ga50ZU=; b=fjLxwCfJkRXjVCaO92egZ3BwvgTYEXZVNKjyFN5LR3DLuzZNlC/m34AVqJ1dT18kDNApnf YtPkQIJ2V1zAi9pq2S1FUv295t44KMqBdVGQnyMd3ucxyLaMP7D75IUMStO5WtexPUh97h mOGEWQjm1S+nENteEaYvBzSVbUeDu1E= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-64-bqdPFo10Ps2mbeHgiQP2iQ-1; Thu, 29 Oct 2020 08:56:39 -0400 X-MC-Unique: bqdPFo10Ps2mbeHgiQP2iQ-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 6A0B9186DD31 for ; Thu, 29 Oct 2020 12:56:38 +0000 (UTC) Received: from localhost (ovpn-114-68.rdu2.redhat.com [10.10.114.68]) by smtp.corp.redhat.com (Postfix) with ESMTP id DEFCD1974D; Thu, 29 Oct 2020 12:56:34 +0000 (UTC) Date: Thu, 29 Oct 2020 08:56:34 -0400 From: Eduardo Habkost To: Paolo Bonzini Subject: Re: [PATCH 03/12] qom: Make object_class_property_add_uint*_ptr() get offset Message-ID: <20201029125634.GJ5733@habkost.net> References: <20201009160122.1662082-1-ehabkost@redhat.com> <20201009160122.1662082-4-ehabkost@redhat.com> <20201021142408.72d2b92f@redhat.com> <20201021133041.GT5733@habkost.net> <20201023173314.6d46ada9@redhat.com> <6f5c3a13-6798-9d7d-e686-69d549366095@redhat.com> MIME-Version: 1.0 In-Reply-To: <6f5c3a13-6798-9d7d-e686-69d549366095@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=ehabkost@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Received-SPF: pass client-ip=63.128.21.124; envelope-from=ehabkost@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/10/29 01:47:28 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, 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_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kevin Wolf , Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= , qemu-devel@nongnu.org, Markus Armbruster , =?utf-8?Q?Marc-Andr=C3=A9?= Lureau , Igor Mammedov , John Snow Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, Oct 28, 2020 at 04:22:40PM +0100, Paolo Bonzini wrote: > On 23/10/20 17:33, Igor Mammedov wrote: > > On Wed, 21 Oct 2020 09:30:41 -0400 > > Eduardo Habkost wrote: > > > >> On Wed, Oct 21, 2020 at 02:24:08PM +0200, Igor Mammedov wrote: > >>> On Fri, 9 Oct 2020 12:01:13 -0400 > >>> Eduardo Habkost wrote: > >>> > >>>> The existing object_class_property_add_uint*_ptr() functions are > >>>> not very useful, because they need a pointer to the property > >>>> value, which can't really be provided before the object is > >>>> created. > >>>> > >>>> Replace the pointer parameter in those functions with a > >>>> `ptrdiff_t offset` parameter. > >>>> > >>>> Include a uint8 class property in check-qom-proplist unit tests, > >>>> to ensure the feature is working. > >>> > >>> > >>> Not sure I like approach, it's reinventing qdev pointer properties in QOM form. > >> > >> Yes, and that's on purpose. If we want to eventually merge the > >> two competing APIs into a single one, we need to make them > >> converge. > >> > >>> I had an impression that Paolo wanted qdev pointer properties be gone > >>> and replaced by something like link properties. > >> > >> This is completely unrelated to qdev pointer properties and link > >> properties. The properties that use object_property_add_uint*_ptr() > >> today are not qdev pointer properties and will never be link > >> properties. They are just integer properties. > > I think this series a step in the right direction, but please take more > "inspiration" from link properties, which are done right. In > particular, properties should have an optional check function and be > read-only unless the check function is there. > > You can make the check function take an uint64_t for simplicity, so that > all the check functions for uint properties have the same prototype. > For example a single "property_check_uint_allow" function can allow > setting the property (which is almost always wrong, but an easy cop out > for this series). A property check callback that needs the property value is a more complex use case, and would require too much property-type-specific boilerplate today. I plan to address it, but not right now. In my next series that makes static properties usable by any QOM object, I will add a separate "allow_set" callback to the internal QOM property API, which will not take the property value as argument. This would be enough for the dev->realized checks that are currently in qdev. Interestingly, there is only one link property check callback function in the QEMU tree that actually cares about the property value: isa_ipmi_bmc_check(). All other cases either don't care about the property value at all (qdev_prop_allow_set_link_before_realize(), object_property_allow_set_link()), or are being misused for something other than property checking (xlnx_dp_set_dpdma()). -- Eduardo