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,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 690B0C48BE5 for ; Wed, 16 Jun 2021 05:19:09 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 3E77F61351 for ; Wed, 16 Jun 2021 05:19:07 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3E77F61351 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4G4YQ255qSz3bv8 for ; Wed, 16 Jun 2021 15:19:06 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lst.de (client-ip=213.95.11.211; helo=verein.lst.de; envelope-from=hch@lst.de; receiver=) Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4G4YPg1R1Lz2xfT for ; Wed, 16 Jun 2021 15:18:47 +1000 (AEST) Received: by verein.lst.de (Postfix, from userid 2407) id EC67D68AFE; Wed, 16 Jun 2021 07:18:39 +0200 (CEST) Date: Wed, 16 Jun 2021 07:18:39 +0200 From: Christoph Hellwig To: Claire Chang Subject: Re: [PATCH v11 09/12] swiotlb: Add restricted DMA alloc/free support Message-ID: <20210616051839.GA27982@lst.de> References: <20210616035240.840463-1-tientzu@chromium.org> <20210616035240.840463-10-tientzu@chromium.org> <20210616045918.GA27537@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: heikki.krogerus@linux.intel.com, thomas.hellstrom@linux.intel.com, peterz@infradead.org, joonas.lahtinen@linux.intel.com, dri-devel@lists.freedesktop.org, chris@chris-wilson.co.uk, grant.likely@arm.com, paulus@samba.org, Frank Rowand , mingo@kernel.org, Marek Szyprowski , sstabellini@kernel.org, Saravana Kannan , Joerg Roedel , "Rafael J . Wysocki" , Christoph Hellwig , Bartosz Golaszewski , bskeggs@redhat.com, linux-pci@vger.kernel.org, xen-devel@lists.xenproject.org, Thierry Reding , intel-gfx@lists.freedesktop.org, matthew.auld@intel.com, linux-devicetree , Jianxiong Gao , Daniel Vetter , Will Deacon , Konrad Rzeszutek Wilk , maarten.lankhorst@linux.intel.com, airlied@linux.ie, Dan Williams , linuxppc-dev@lists.ozlabs.org, jani.nikula@linux.intel.com, Rob Herring , rodrigo.vivi@intel.com, Bjorn Helgaas , boris.ostrovsky@oracle.com, Andy Shevchenko , jgross@suse.com, Nicolas Boichat , Greg KH , Randy Dunlap , lkml , Tomasz Figa , "list@263.net:IOMMU DRIVERS" , Jim Quinlan , xypron.glpk@gmx.de, Robin Murphy , bauerman@linux.ibm.com Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Wed, Jun 16, 2021 at 01:10:02PM +0800, Claire Chang wrote: > On Wed, Jun 16, 2021 at 12:59 PM Christoph Hellwig wrote: > > > > On Wed, Jun 16, 2021 at 12:04:16PM +0800, Claire Chang wrote: > > > Just noticed that after propagating swiotlb_force setting into > > > io_tlb_default_mem->force, the memory allocation behavior for > > > swiotlb_force will change (i.e. always skipping arch_dma_alloc and > > > dma_direct_alloc_from_pool). > > > > Yes, I think we need to split a "use_for_alloc" flag from the force flag. > > How about splitting is_dev_swiotlb_force into is_swiotlb_force_bounce > (io_tlb_mem->force_bounce) and is_swiotlb_force_alloc > (io_tlb_mem->force_alloc)? Yes, something like that. I'd probably not use force for the alloc side given that we otherwise never allocte from the swiotlb buffer.