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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 03475C67790 for ; Wed, 25 Jul 2018 21:35:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ABB8E20671 for ; Wed, 25 Jul 2018 21:35:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ABB8E20671 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731411AbeGYWtb (ORCPT ); Wed, 25 Jul 2018 18:49:31 -0400 Received: from mga12.intel.com ([192.55.52.136]:43391 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730370AbeGYWtb (ORCPT ); Wed, 25 Jul 2018 18:49:31 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 25 Jul 2018 14:35:55 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,402,1526367600"; d="scan'208";a="243319781" Received: from djiang5-desk3.ch.intel.com ([143.182.136.93]) by orsmga005.jf.intel.com with ESMTP; 25 Jul 2018 14:35:33 -0700 Subject: Re: [PATCH v2 0/6] kaddr and pfn can be NULL to ->direct_access() To: Huaisheng Ye , linux-nvdimm@lists.01.org, dan.j.williams@intel.com Cc: ross.zwisler@linux.intel.com, willy@infradead.org, vishal.l.verma@intel.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, viro@zeniv.linux.org.uk, martin.petersen@oracle.com, axboe@kernel.dk, gregkh@linuxfoundation.org, bart.vanassche@wdc.com, jack@suse.cz, agk@redhat.com, snitzer@redhat.com, dm-devel@redhat.com, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, linux-fsdevel@vger.kernel.org, chengnt@lenovo.com, colyli@suse.de, Huaisheng Ye References: <20180725162849.8320-1-yehs2007@zoho.com> From: Dave Jiang Openpgp: preference=signencrypt Autocrypt: addr=dave.jiang@intel.com; prefer-encrypt=mutual; keydata= xsPuBE6TbysRDACKOBHZT4ez/3/idMBVQP+cMIJAWfTTLqbHVYLdHMHh4h6IXWLqWgc9AYTx /ajdOrBVGSK9kMuvqRi0iRO1QLOMUAIc2n/44vh/3Fe54QYfgbndeXhHZi7YEwjiTCbpQ336 pS0rS2qQaA8GzFwu96OslLI05j9Ygaqy73qmuk3wxomIYiu9a97aN3oVv1RyTp6gJK1NWT3J On17P1yWUYPvY3KJtpVqnRLkLZeOIiOahgf9+qiYqPhKQI1Ycx4YhbqkNmDG1VqdMtEWREZO DpTti6oecydN37MW1Y+YSzWYDVLWfoLUr2tBveGCRLf/U2n+Tm2PlJR0IZq+BhtuIUVcRLQW vI+XenR8j3vHVNHs9UXW/FPB8Xb5fwY2bJniZ+B4G67nwelhMNWe7H9IcEaI7Eo32fZk+9fo x6GDAhdT0pEetwuhkmI0YYD7cQj1mEx1oEbzX2p/HRW9sHTSv0V2zKbkPvii3qgvCoDb1uLd 4661UoSG0CYaAx8TwBxUqjsBAO9FXDhLHZJadyHmWp64xQGnNgBathuqoSsIWgQWBpfhDACA OYftX52Wp4qc3ZT06NPzGTV35xr4DVftxxUHiwzB/bzARfK8tdoW4A44gN3P03DAu+UqLoqm UP/e8gSLEjoaebjMu8c2iuOhk1ayHkDPc2gugTgLLBWPkhvIEV4rUV9C7TsgAAvNNDAe8X00 Tu1m01A4ToLpYsNWEtM9ZRdKXSo6YS45DFRhel29ZRz24j4ZNIxN9Bee/fn7FrL4HgO01yH+ QULDAtU87AkVoBdU5xBJVj7tGosuV+ia4UCWXjTzb+ERek2503OvNq4xqche3RMoZLsSHiOj 5PjMNX4EA6pf5kRWdNutjmAsXrpZrnviWMPy+zHUzHIw/gaI00lHMjS0P99A7ay/9BjtsIBx lJZ09Kp6SE0EiZpFIxB5D0ji6rHu3Qblwq+WjM2+1pydVxqt2vt7+IZgEB4Qm6rml835UB89 TTkMtiIXJ+hMC/hajIuFSah+CDkfagcrt1qiaVoEAs/1cCuAER+h5ClMnLZPPxNxphsqkXxn 3MVJcMEL/iaMimP3oDXJoK3O+u3gC3p55A/LYZJ7hP9lHTT4MtgwmgBp9xPeVFWx3rwQOKix SPONHlkjfvn4dUHmaOmJyKgtt5htpox+XhBkuCZ5UWpQ40/GyVypWyBXtqNx/0IKByXy4QVm QjUL/U2DchYhW+2w8rghIhkuHX2YOdldyEvXkzN8ysGR31TDwshg600k4Q/UF/MouC2ZNeMa y8I0whHBFTwSjN5T1F9cvko4PsHNB3QH4M4tbArwn4RzSX6Hfxoq59ziyI4Et6sE5SyiVEZQ DhKZ8VU61uUaYHDdid8xKU4sV5IFCERIoIwieEAkITNvCdFtuXl9gugzld7IHbOTRaGy4M+M gOyAvSe5ysBrXhY+B0d+EYif1I8s4PbnkH2xehof++lQuy3+1TZcweSx1f/uF6d92ZDkvJzQ QbkicMLaPy0IS5XIMkkpD1zIO0jeaHcTm3uzB9k8N9y4tA2ELWVR/iFZigrtrwpIJtJLUieB 89EOJLR6xbksSrFhQ80oRGF2ZSBKaWFuZyAoV29yaykgPGRhdmUuamlhbmdAaW50ZWwuY29t PsJ9BBMRCAAlAhsjBgsJCAcDAgYVCAIJCgsEFgIDAQIeAQIXgAUCUZEwDwIZAQAKCRBkFcTx ZqO5Ps8HAP4kF/KAor80fNwT7osSHGG5rLFPR/Yc5V0QpqkU8DhZDgEAoStRa/a6Mtq3Ri1H B84kFIqSQ9ME5049k6k1K7wdXcvOwE0ETpNvKxAEANGHLx0q/R99wzbVdnRthIZttNQ6M4R8 AAtEypE9JG3PLrEd9MUB5wf0fB/2Jypec3x935mRW3Zt1i+TrzjQDzMV5RyTtpWI7PwIh5IZ 0h4OV2yQHFVViHi6lubCRypQYiMzTmEKua3LeBGvUR9vVmpPJZ/UP6VajKqywjPHYBwLAAMF A/9B/PdGc1sZHno0ezuwZO2J9BOsvASNUzamO9to5P9VHTA6UqRvyfXJpNxLF1HjT4ax7Xn4 wGr6V1DCG3JYBmwIZjfinrLINKEK43L+sLbVVi8Mypc32HhNx/cPewROY2vPb4U7y3jhPBtt lt0ZMb75Lh7zY3TnGLOx1AEzmqwZSMJhBBgRCAAJBQJOk28rAhsMAAoJEGQVxPFmo7k+qiUB AKH0QWC+BBBn3pa9tzOz5hTrup+GIzf5TcuCsiAjISEqAPkBTGk5iiGrrHkxsz8VulDVpNxk o6nmKbYpUAltQObU2w== Message-ID: <3689520a-4a49-4e1f-6ee9-2ff4a9796b9f@intel.com> Date: Wed, 25 Jul 2018 14:35:32 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20180725162849.8320-1-yehs2007@zoho.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Pretty straight forward series. Huaisheng, I can apply the whole series to libnvdimm if we can get ack's from maintainer of dcssblk and dm-writecache for the respective bits. On 07/25/2018 09:28 AM, Huaisheng Ye wrote: > From: Huaisheng Ye > > Changes since v1 [1]: > * Involve the previous patches for pfn can be NULL. > * Reword the patch descriptions according to Christian's comment. > * According to Ross's suggestion, replace local pointer dummy_addr > with NULL within md/dm-writecache for direct_access. > > [1]: https://lkml.org/lkml/2018/7/24/199 > > Some functions within fs/dax, dax/super and md/dm-writecache don't > need to get local pointer kaddr or variable pfn from direct_access. > Assigning NULL to kaddr or pfn to ->direct_access() is more > straightforward and simple than offering a useless local pointer or > variable. > > So all ->direct_access() need to check the validity of pointer kaddr > and pfn for NULL assignment. If either of them is equal to NULL, that > is to say callers may have no need for kaddr or pfn, so this series of > patch are prepared for allowing them to pass in NULL instead of having > to pass in a local pointer or variable that they then just throw away. > > Huaisheng Ye (6): > libnvdimm, pmem: kaddr and pfn can be NULL to ->direct_access() > s390, dcssblk: kaddr and pfn can be NULL to ->direct_access() > tools/testing/nvdimm: kaddr and pfn can be NULL to ->direct_access() > dax/super: Do not request a pointer kaddr when not required > md/dm-writecache: Don't request pointer dummy_addr when not required > filesystem-dax: Do not request kaddr and pfn when not required > > drivers/dax/super.c | 3 +-- > drivers/md/dm-writecache.c | 3 +-- > drivers/nvdimm/pmem.c | 7 +++++-- > drivers/s390/block/dcssblk.c | 8 +++++--- > fs/dax.c | 13 ++++--------- > tools/testing/nvdimm/pmem-dax.c | 12 ++++++++---- > 6 files changed, 24 insertions(+), 22 deletions(-) >