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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9833EB64D9 for ; Mon, 3 Jul 2023 01:33:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229777AbjGCBdw (ORCPT ); Sun, 2 Jul 2023 21:33:52 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43646 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229671AbjGCBdv (ORCPT ); Sun, 2 Jul 2023 21:33:51 -0400 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AFBA712E for ; Sun, 2 Jul 2023 18:33:49 -0700 (PDT) Received: from lhrpeml500005.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4QvSzw3S8yz688Z4; Mon, 3 Jul 2023 09:30:52 +0800 (CST) Received: from localhost (10.34.206.101) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Mon, 3 Jul 2023 02:33:43 +0100 Date: Mon, 3 Jul 2023 09:33:39 +0800 From: Jonathan Cameron To: "nifan@outlook.com" CC: Fan Ni , "qemu-devel@nongnu.org" , "linux-cxl@vger.kernel.org" , "gregory.price@memverge.com" , "hchkuo@avery-design.com.tw" , "cbrowy@avery-design.com" , "ira.weiny@intel.com" , "dan.j.williams@intel.com" , Adam Manzanares , "dave@stgolabs.net" , "nmtadam.samsung@gmail.com" Subject: Re: [RFC 7/7] hw/mem/cxl_type3: add read/write support to dynamic capacity Message-ID: <20230703093339.00002fb2@Huawei.com> In-Reply-To: References: <20230511175609.2091136-1-fan.ni@samsung.com> <20230511175609.2091136-8-fan.ni@samsung.com> <20230515162212.0000275c@Huawei.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.34.206.101] X-ClientProxiedBy: lhrpeml500003.china.huawei.com (7.191.162.67) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org On Wed, 28 Jun 2023 10:09:47 -0700 "nifan@outlook.com" wrote: > The 05/15/2023 16:22, Jonathan Cameron wrote: > > On Thu, 11 May 2023 17:56:40 +0000 > > Fan Ni wrote: > > > > > From: Fan Ni > > > > > > Before the change, read from or write to dynamic capacity of the memory > > > device is not support as 1) no host backed file/memory is provided for > > > it; 2) no address space is created for the dynamic capacity. > > > > Ah nice. I should have read ahead. Probably makes sense to reorder things > > so that when we present DCD region it will work. > > We can back dynamic capacity with host memory/file and create address > space for dc regions, but until extents can be added we should not expect > any read/write can happen to the dynamic capacity, right? True. Seems logically 'unusual' though to set up the routing etc, but not plumb the actual memory access i until later. I guess it all comes together in the end and doing it this way lets you handle the extent mapping later. So fine to leave it as you have it. Jonathan 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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id 048B8EB64D9 for ; Mon, 3 Jul 2023 01:34:33 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1qG8S9-00082m-Te; Sun, 02 Jul 2023 21:34:10 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qG8S5-00082a-DC for qemu-devel@nongnu.org; Sun, 02 Jul 2023 21:34:06 -0400 Received: from frasgout.his.huawei.com ([185.176.79.56]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1qG8S2-0006Mt-FR for qemu-devel@nongnu.org; Sun, 02 Jul 2023 21:34:04 -0400 Received: from lhrpeml500005.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4QvSzw3S8yz688Z4; Mon, 3 Jul 2023 09:30:52 +0800 (CST) Received: from localhost (10.34.206.101) by lhrpeml500005.china.huawei.com (7.191.163.240) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.27; Mon, 3 Jul 2023 02:33:43 +0100 Date: Mon, 3 Jul 2023 09:33:39 +0800 To: "nifan@outlook.com" CC: Fan Ni , "qemu-devel@nongnu.org" , "linux-cxl@vger.kernel.org" , "gregory.price@memverge.com" , "hchkuo@avery-design.com.tw" , "cbrowy@avery-design.com" , "ira.weiny@intel.com" , "dan.j.williams@intel.com" , Adam Manzanares , "dave@stgolabs.net" , "nmtadam.samsung@gmail.com" Subject: Re: [RFC 7/7] hw/mem/cxl_type3: add read/write support to dynamic capacity Message-ID: <20230703093339.00002fb2@Huawei.com> In-Reply-To: References: <20230511175609.2091136-1-fan.ni@samsung.com> <20230511175609.2091136-8-fan.ni@samsung.com> <20230515162212.0000275c@Huawei.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.1.0 (GTK 3.24.33; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.34.206.101] X-ClientProxiedBy: lhrpeml500003.china.huawei.com (7.191.162.67) To lhrpeml500005.china.huawei.com (7.191.163.240) X-CFilter-Loop: Reflected Received-SPF: pass client-ip=185.176.79.56; envelope-from=jonathan.cameron@huawei.com; helo=frasgout.his.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-to: Jonathan Cameron From: Jonathan Cameron via Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Wed, 28 Jun 2023 10:09:47 -0700 "nifan@outlook.com" wrote: > The 05/15/2023 16:22, Jonathan Cameron wrote: > > On Thu, 11 May 2023 17:56:40 +0000 > > Fan Ni wrote: > > > > > From: Fan Ni > > > > > > Before the change, read from or write to dynamic capacity of the memory > > > device is not support as 1) no host backed file/memory is provided for > > > it; 2) no address space is created for the dynamic capacity. > > > > Ah nice. I should have read ahead. Probably makes sense to reorder things > > so that when we present DCD region it will work. > > We can back dynamic capacity with host memory/file and create address > space for dc regions, but until extents can be added we should not expect > any read/write can happen to the dynamic capacity, right? True. Seems logically 'unusual' though to set up the routing etc, but not plumb the actual memory access i until later. I guess it all comes together in the end and doing it this way lets you handle the extent mapping later. So fine to leave it as you have it. Jonathan