Received: by 2002:a05:7412:da14:b0:e2:908c:2ebd with SMTP id fe20csp785282rdb; Fri, 6 Oct 2023 21:56:43 -0700 (PDT) X-Google-Smtp-Source: AGHT+IHtas8uD7jr6pFdIKLPFeH3u1bBTeV28OAlNwJGYMLTeu2Yfky7fdE5rmZaIn8sOWeJ+urt X-Received: by 2002:a17:902:b718:b0:1bd:d141:f02d with SMTP id d24-20020a170902b71800b001bdd141f02dmr8024897pls.68.1696654603126; Fri, 06 Oct 2023 21:56:43 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1696654603; cv=none; d=google.com; s=arc-20160816; b=l4i17zjESuQOs5tpJd8HuYfPVZbYlnbWN+LNgaOhYTtdEDcCuNf4NCcZPXJlSR3AT3 b+TP3Nc53ACb/Q9rX5FQZU6Ik8CDWwtRJ2tLtqU7y9Vaay+EXLwTkxh5+kVeC/GImVkF jrRUiigA6EJGfq5/Gnezs3FAelqPEa8O1i3JKtbUl3j1PeAEf+u0q71mgiFbskbqDnkn N/PjjIzBacz0ALg12lm+U/BaXXNZPm2XbbHhf0yUyBmb5Bho6uVagFtZsydPDWdsLZVQ NkRB6Xj2pzSxL/gXheVpPKBv3v3jOHNDzI9yP6t94kTObWbk1aAMPgxYBjp+TnVsfEyy d1Ig== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:cc:to:subject :message-id:date:from:in-reply-to:references:mime-version :dkim-signature; bh=7eOM8yvazKaQpnrAtPNGZKXRoMy3llC+Bk4NxNh92q4=; fh=apgx5waM4Z/PqT0hh3nfatlLD0du2J7GP0abt0a+WZY=; b=ITpilegK+f6MS/n2s+pUB16fvSdAuwIejlAOv2jdZ4tYQV2eLBpmpG3DZSyNjS9W8+ n9oHhYiWOa3C6U1TMcs9808prbr+quG4MgHcOsl/cdvI6UhZtuUIjYdQIGqRC1HflGJ5 82BdX3F8Rfzwg4MekDCkO+YSkEnv/wsLg12foQRJ9x2x06XnIIFP5t7jgxLwyRzluPnC d7gZ9UZvtpNG5ikBtIbGjoi/Z+CWeNDBY2dBvJAR0tlTFVddbJT/QVw3Zv4SUumkPUoS l3AaqIGOyWlTDCqVgiRln99UTYR63yDIwIPYlJ6yvqFS7HJEIZUE7O1hyh6aruAsuWF3 Chug== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=HWxpdLb6; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from howler.vger.email (howler.vger.email. [23.128.96.34]) by mx.google.com with ESMTPS id t1-20020a170902e1c100b001c33d33975esi4859181pla.133.2023.10.06.21.56.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Oct 2023 21:56:43 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) client-ip=23.128.96.34; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=HWxpdLb6; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.34 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by howler.vger.email (Postfix) with ESMTP id 0FA2C80A167C; Fri, 6 Oct 2023 21:56:06 -0700 (PDT) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.10 at howler.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1343510AbjJGEze (ORCPT + 99 others); Sat, 7 Oct 2023 00:55:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37718 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234114AbjJGEzc (ORCPT ); Sat, 7 Oct 2023 00:55:32 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B8093BD for ; Fri, 6 Oct 2023 21:55:30 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 40027C433C8 for ; Sat, 7 Oct 2023 04:55:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1696654530; bh=2a1Ky/mZH2hKASG6nu8YJuKy2KoxgXfikcJ2YLB+iBs=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=HWxpdLb6+PBUeZMZRWmrE2lLvuut56PjpJirWspEJBkC+ZIw2a7qoAP8AOTcKZU5o HuezpFW3JK0UdOnmarLvMGsFK2dW5mS2ZL4XA9yOfHmCg0DOrwbiT2GWm+/RsvCXSO bDL1xLXZ60k1M2is1wKUSrpXS0b/AdJt+jDyf59uefpYeWRqpYSXQ7nFsbdWuHAJZM 0qUI7MJ4lNiTXksGjFJaS71HW8g1PjQxRWgu2SHqoF0Xh8Kkm7fDPFDOQqhBB92BoT z460AEbnEQcXpMyPUdHaNU630YixVsXVNQCSWi4etTrxCFuKoq6m2zIyOv+R4NASNu 6UqJ6n8IXL84A== Received: by mail-ed1-f54.google.com with SMTP id 4fb4d7f45d1cf-53447d0241eso5154138a12.3 for ; Fri, 06 Oct 2023 21:55:30 -0700 (PDT) X-Gm-Message-State: AOJu0Yw2Vm9fChIodvwQ+4VfK2PGuQtmPglna+yZEKVDUEErc5YXrkwL wd9KgdazH2MU4HdF9kRK5wb/vqUVIeRJPsJgqG4= X-Received: by 2002:a05:6402:7d6:b0:523:1fa2:4f40 with SMTP id u22-20020a05640207d600b005231fa24f40mr8763067edy.19.1696654528679; Fri, 06 Oct 2023 21:55:28 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: From: Huacai Chen Date: Sat, 7 Oct 2023 12:55:14 +0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: kmap() transformation: Question about copy_user_highpage To: Deepak R Varma Cc: WANG Xuerui , loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, Ira Weiny , "Fabio M. De Francesco" Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=2.4 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,MAILING_LIST_MULTI, RCVD_IN_SBL_CSS,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on howler.vger.email Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (howler.vger.email [0.0.0.0]); Fri, 06 Oct 2023 21:56:06 -0700 (PDT) X-Spam-Level: ** Hi, Deepak, On Sat, Oct 7, 2023 at 2:46=E2=80=AFAM Deepak R Varma wrote= : > > Hello, > I am attempting to work on replacing the kmap[_atomic]() calls by > kmap_local_page() function call. A detail on this change can be found her= e [0]. > > I would like to know if this function: > arch/loongarch/mm/init.c::copy_user_highpage() > is currently in use or is it a dead code? > > If this code is not in use, can this be removed instead? However, if it i= s in > use, can you comment why kmap_atomic() was preferred over kmap() > function call? I think this function will be used for the 32bit kernel, and we will add loongarch32 support in the near future. But on the other hand, you can replace kmap_atomic() with kmap_local_page(), there is no special reason to use kmap_atomic(). Huacai > > [0] https://lore.kernel.org/all/20201029222652.302358281@linutronix.de/ > > Thank you, > Deepak. > > >