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=-5.3 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 7F9F2C433ED for ; Mon, 10 May 2021 15:05:30 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 0896C6147F for ; Mon, 10 May 2021 15:05:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0896C6147F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.125314.235895 (Exim 4.92) (envelope-from ) id 1lg7TF-0007Vi-Ji; Mon, 10 May 2021 15:05:21 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 125314.235895; Mon, 10 May 2021 15:05:21 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lg7TF-0007Vb-Gh; Mon, 10 May 2021 15:05:21 +0000 Received: by outflank-mailman (input) for mailman id 125314; Mon, 10 May 2021 15:05:20 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1lg7TD-0007VS-Tx for xen-devel@lists.xenproject.org; Mon, 10 May 2021 15:05:19 +0000 Received: from verein.lst.de (unknown [213.95.11.211]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 9964c90b-7e54-44ce-b96f-8a492216a985; Mon, 10 May 2021 15:05:19 +0000 (UTC) Received: by verein.lst.de (Postfix, from userid 2407) id 2DAB567373; Mon, 10 May 2021 17:05:17 +0200 (CEST) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 9964c90b-7e54-44ce-b96f-8a492216a985 Date: Mon, 10 May 2021 17:05:16 +0200 From: Christoph Hellwig To: Claire Chang Cc: Rob Herring , mpe@ellerman.id.au, Joerg Roedel , Will Deacon , Frank Rowand , Konrad Rzeszutek Wilk , boris.ostrovsky@oracle.com, jgross@suse.com, Christoph Hellwig , Marek Szyprowski , benh@kernel.crashing.org, paulus@samba.org, "list@263.net:IOMMU DRIVERS" , sstabellini@kernel.org, Robin Murphy , grant.likely@arm.com, xypron.glpk@gmx.de, Thierry Reding , mingo@kernel.org, bauerman@linux.ibm.com, peterz@infradead.org, Greg KH , Saravana Kannan , "Rafael J . Wysocki" , heikki.krogerus@linux.intel.com, Andy Shevchenko , Randy Dunlap , Dan Williams , Bartosz Golaszewski , linux-devicetree , lkml , linuxppc-dev@lists.ozlabs.org, xen-devel@lists.xenproject.org, Nicolas Boichat , Jim Quinlan , tfiga@chromium.org, bskeggs@redhat.com, bhelgaas@google.com, chris@chris-wilson.co.uk, daniel@ffwll.ch, airlied@linux.ie, dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, jani.nikula@linux.intel.com, jxgao@google.com, joonas.lahtinen@linux.intel.com, linux-pci@vger.kernel.org, maarten.lankhorst@linux.intel.com, matthew.auld@intel.com, nouveau@lists.freedesktop.org, rodrigo.vivi@intel.com, thomas.hellstrom@linux.intel.com Subject: Re: [PATCH v6 08/15] swiotlb: Bounce data from/to restricted DMA pool if available Message-ID: <20210510150516.GE28066@lst.de> References: <20210510095026.3477496-1-tientzu@chromium.org> <20210510095026.3477496-9-tientzu@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210510095026.3477496-9-tientzu@chromium.org> User-Agent: Mutt/1.5.17 (2007-11-01) > +static inline bool is_dev_swiotlb_force(struct device *dev) > +{ > +#ifdef CONFIG_DMA_RESTRICTED_POOL > + if (dev->dma_io_tlb_mem) > + return true; > +#endif /* CONFIG_DMA_RESTRICTED_POOL */ > + return false; > +} > + > /* If SWIOTLB is active, use its maximum mapping size */ > if (is_swiotlb_active(dev) && > - (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE)) > + (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE || > + is_dev_swiotlb_force(dev))) This is a mess. I think the right way is to have an always_bounce flag in the io_tlb_mem structure instead. Then the global swiotlb_force can go away and be replace with this and the fact that having no io_tlb_mem structure at all means forced no buffering (after a little refactoring).