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=-2.2 required=3.0 tests=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 DDC6DC432C0 for ; Tue, 3 Dec 2019 02:37:34 +0000 (UTC) Received: from whitealder.osuosl.org (smtp1.osuosl.org [140.211.166.138]) (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 ABD4620684 for ; Tue, 3 Dec 2019 02:37:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org ABD4620684 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by whitealder.osuosl.org (Postfix) with ESMTP id 6C3D9814A2; Tue, 3 Dec 2019 02:37:34 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from whitealder.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id X6hiNtZjfEUO; Tue, 3 Dec 2019 02:37:30 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [140.211.9.56]) by whitealder.osuosl.org (Postfix) with ESMTP id C0F478746D; Tue, 3 Dec 2019 02:37:30 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id B3598C1797; Tue, 3 Dec 2019 02:37:30 +0000 (UTC) Received: from fraxinus.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 16263C087F for ; Tue, 3 Dec 2019 02:37:29 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by fraxinus.osuosl.org (Postfix) with ESMTP id 06FBB8626F for ; Tue, 3 Dec 2019 02:37:29 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from fraxinus.osuosl.org ([127.0.0.1]) by localhost (.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id clRTXXl4MBgE for ; Tue, 3 Dec 2019 02:37:27 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.7.6 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by fraxinus.osuosl.org (Postfix) with ESMTPS id D3F4D85DA5 for ; Tue, 3 Dec 2019 02:37:27 +0000 (UTC) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Dec 2019 18:37:26 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,271,1571727600"; d="scan'208";a="222658134" Received: from allen-box.sh.intel.com (HELO [10.239.159.136]) ([10.239.159.136]) by orsmga002.jf.intel.com with ESMTP; 02 Dec 2019 18:37:24 -0800 Subject: Re: [PATCH v2 5/8] iommu/vt-d: Add first level page table interfaces To: Jacob Pan References: <20191128022550.9832-1-baolu.lu@linux.intel.com> <20191128022550.9832-6-baolu.lu@linux.intel.com> <20191202152732.3d9c6589@jacob-builder> From: Lu Baolu Message-ID: Date: Tue, 3 Dec 2019 10:36:48 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.2.1 MIME-Version: 1.0 In-Reply-To: <20191202152732.3d9c6589@jacob-builder> Content-Language: en-US Cc: kevin.tian@intel.com, Yi Sun , ashok.raj@intel.com, kvm@vger.kernel.org, sanjay.k.kumar@intel.com, yi.y.sun@intel.com, linux-kernel@vger.kernel.org, Alex Williamson , iommu@lists.linux-foundation.org, David Woodhouse X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Errors-To: iommu-bounces@lists.linux-foundation.org Sender: "iommu" Hi, On 12/3/19 7:27 AM, Jacob Pan wrote: > On Thu, 28 Nov 2019 10:25:47 +0800 > Lu Baolu wrote: > >> This adds functions to manipulate first level page tables >> which could be used by a scalale mode capable IOMMU unit. >> > FL and SL page tables are very similar, and I presume we are not using > all the flag bits in FL paging structures for DMA mapping. Are there > enough relevant differences to warrant a new set of helper functions > for FL? Or we can merge into one. > I ever thought about this and I am still open for this suggestion. We had a quick compare on these two page tables. The only concern is the read/write/present encoding. The present bit in first level implies read permission while second level page table explicitly has a READ bit. (recalled from memory, correct me if it's bad. :-)). Anyway, let's listen to more opinions. Best regards, baolu _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu