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,URIBL_BLOCKED,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 5E7EDC32753 for ; Wed, 14 Aug 2019 08:38:47 +0000 (UTC) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org [140.211.169.12]) (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 3146D2084F for ; Wed, 14 Aug 2019 08:38:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3146D2084F Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=8bytes.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=iommu-bounces@lists.linux-foundation.org Received: from mail.linux-foundation.org (localhost [127.0.0.1]) by mail.linuxfoundation.org (Postfix) with ESMTP id 00549C51; Wed, 14 Aug 2019 08:38:46 +0000 (UTC) Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 4C552C3E for ; Wed, 14 Aug 2019 08:38:45 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from theia.8bytes.org (8bytes.org [81.169.241.247]) by smtp1.linuxfoundation.org (Postfix) with ESMTPS id D57A4CF for ; Wed, 14 Aug 2019 08:38:44 +0000 (UTC) Received: by theia.8bytes.org (Postfix, from userid 1000) id 20E3C2E2; Wed, 14 Aug 2019 10:38:43 +0200 (CEST) Date: Wed, 14 Aug 2019 10:38:43 +0200 From: Joerg Roedel To: Lu Baolu Subject: Re: [PATCH v6 5/8] iommu: Add bounce page APIs Message-ID: <20190814083842.GB22669@8bytes.org> References: <20190730045229.3826-1-baolu.lu@linux.intel.com> <20190730045229.3826-6-baolu.lu@linux.intel.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190730045229.3826-6-baolu.lu@linux.intel.com> User-Agent: Mutt/1.9.4 (2018-02-28) Cc: alan.cox@intel.com, Christoph Hellwig , Stefano Stabellini , ashok.raj@intel.com, Jonathan Corbet , pengfei.xu@intel.com, Ingo Molnar , David Woodhouse , kevin.tian@intel.com, Konrad Rzeszutek Wilk , Steven Rostedt , Bjorn Helgaas , Boris Ostrovsky , mika.westerberg@linux.intel.com, Alan Cox , Juergen Gross , Greg Kroah-Hartman , Mika Westerberg , linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, jacob.jun.pan@intel.com, Robin Murphy X-BeenThere: iommu@lists.linux-foundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Development issues for Linux IOMMU support List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: iommu-bounces@lists.linux-foundation.org Errors-To: iommu-bounces@lists.linux-foundation.org Hi Lu Baolu, On Tue, Jul 30, 2019 at 12:52:26PM +0800, Lu Baolu wrote: > * iommu_bounce_map(dev, addr, paddr, size, dir, attrs) > - Map a buffer start at DMA address @addr in bounce page > manner. For buffer parts that doesn't cross a whole > minimal IOMMU page, the bounce page policy is applied. > A bounce page mapped by swiotlb will be used as the DMA > target in the IOMMU page table. Otherwise, the physical > address @paddr is mapped instead. > > * iommu_bounce_unmap(dev, addr, size, dir, attrs) > - Unmap the buffer mapped with iommu_bounce_map(). The bounce > page will be torn down after the bounced data get synced. > > * iommu_bounce_sync(dev, addr, size, dir, target) > - Synce the bounced data in case the bounce mapped buffer is > reused. I don't really get why this API extension is needed for your use-case. Can't this just be done using iommu_map/unmap operations? Can you please elaborate a bit why these functions are needed? Regards, Joerg _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu