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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 1DDCAC433E7 for ; Tue, 13 Oct 2020 20:53:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C6C10208D5 for ; Tue, 13 Oct 2020 20:53:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726753AbgJMUxi (ORCPT ); Tue, 13 Oct 2020 16:53:38 -0400 Received: from mga17.intel.com ([192.55.52.151]:54071 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726186AbgJMUxi (ORCPT ); Tue, 13 Oct 2020 16:53:38 -0400 IronPort-SDR: gI8MkOnOGO61aP07XY6CCWHG9J8FvCUX/dOJGBzQnYJFTP4ej18aKmY+Fn52D+I38Lw4zhRGT9 RQaSxhwXc52g== X-IronPort-AV: E=McAfee;i="6000,8403,9773"; a="145845033" X-IronPort-AV: E=Sophos;i="5.77,371,1596524400"; d="scan'208";a="145845033" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2020 13:53:36 -0700 IronPort-SDR: 6pC5EU5QwoXbsJ9AhSALdpEnefHex0iyEFu7THvX1eaSFNd77CbWePaQQdxa3yUvYDZ6VBgRvg Vwn0OOQPMwwA== X-IronPort-AV: E=Sophos;i="5.77,371,1596524400"; d="scan'208";a="313946459" Received: from iweiny-desk2.sc.intel.com (HELO localhost) ([10.3.52.147]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Oct 2020 13:53:35 -0700 Date: Tue, 13 Oct 2020 13:52:49 -0700 From: Ira Weiny To: Christoph Hellwig Cc: Andrew Morton , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Andy Lutomirski , Peter Zijlstra , x86@kernel.org, Dave Hansen , Dan Williams , Fenghua Yu , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, kexec@lists.infradead.org, linux-bcache@vger.kernel.org, linux-mtd@lists.infradead.org, devel@driverdev.osuosl.org, linux-efi@vger.kernel.org, linux-mmc@vger.kernel.org, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-nfs@vger.kernel.org, ceph-devel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-aio@kvack.org, io-uring@vger.kernel.org, linux-erofs@lists.ozlabs.org, linux-um@lists.infradead.org, linux-ntfs-dev@lists.sourceforge.net, reiserfs-devel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-nilfs@vger.kernel.org, cluster-devel@redhat.com, ecryptfs@vger.kernel.org, linux-cifs@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-afs@lists.infradead.org, linux-rdma@vger.kernel.org, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, drbd-dev@lists.linbit.com, linux-block@vger.kernel.org, xen-devel@lists.xenproject.org, linux-cachefs@redhat.com, samba-technical@lists.samba.org, intel-wired-lan@lists.osuosl.org Subject: Re: [PATCH RFC PKS/PMEM 24/58] fs/freevxfs: Utilize new kmap_thread() Message-ID: <20201013205248.GJ2046448@iweiny-DESK2.sc.intel.com> References: <20201009195033.3208459-1-ira.weiny@intel.com> <20201009195033.3208459-25-ira.weiny@intel.com> <20201013112544.GA5249@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201013112544.GA5249@infradead.org> User-Agent: Mutt/1.11.1 (2018-12-01) Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Tue, Oct 13, 2020 at 12:25:44PM +0100, Christoph Hellwig wrote: > > - kaddr = kmap(pp); > > + kaddr = kmap_thread(pp); > > memcpy(kaddr, vip->vii_immed.vi_immed + offset, PAGE_SIZE); > > - kunmap(pp); > > + kunmap_thread(pp); > > You only Cced me on this particular patch, which means I have absolutely > no idea what kmap_thread and kunmap_thread actually do, and thus can't > provide an informed review. Sorry the list was so big I struggled with who to CC and on which patches. > > That being said I think your life would be a lot easier if you add > helpers for the above code sequence and its counterpart that copies > to a potential hughmem page first, as that hides the implementation > details from most users. Matthew Wilcox and Al Viro have suggested similar ideas. https://lore.kernel.org/lkml/20201013205012.GI2046448@iweiny-DESK2.sc.intel.com/ Ira