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=-15.4 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 15F6EC48BE6 for ; Wed, 16 Jun 2021 17:02:59 +0000 (UTC) Received: from smtp3.osuosl.org (smtp3.osuosl.org [140.211.166.136]) (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 A645860FE6 for ; Wed, 16 Jun 2021 17:02:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org A645860FE6 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=virtualization-bounces@lists.linux-foundation.org Received: from localhost (localhost [127.0.0.1]) by smtp3.osuosl.org (Postfix) with ESMTP id 51FC860A7A; Wed, 16 Jun 2021 17:02:58 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp3.osuosl.org ([127.0.0.1]) by localhost (smtp3.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Edn0ETo4uJFs; Wed, 16 Jun 2021 17:02:57 +0000 (UTC) Received: from lists.linuxfoundation.org (lf-lists.osuosl.org [IPv6:2605:bc80:3010:104::8cd3:938]) by smtp3.osuosl.org (Postfix) with ESMTPS id C5FFD60A62; Wed, 16 Jun 2021 17:02:56 +0000 (UTC) Received: from lf-lists.osuosl.org (localhost [127.0.0.1]) by lists.linuxfoundation.org (Postfix) with ESMTP id 894B1C000E; Wed, 16 Jun 2021 17:02:56 +0000 (UTC) Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 117D1C000B; Wed, 16 Jun 2021 17:02:55 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id E632040355; Wed, 16 Jun 2021 17:02:54 +0000 (UTC) X-Virus-Scanned: amavisd-new at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id dRfMnOPCexQM; Wed, 16 Jun 2021 17:02:53 +0000 (UTC) X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 X-Greylist: domain auto-whitelisted by SQLgrey-1.8.0 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp4.osuosl.org (Postfix) with ESMTP id 8E04C40348; Wed, 16 Jun 2021 17:02:53 +0000 (UTC) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0690C1042; Wed, 16 Jun 2021 10:02:52 -0700 (PDT) Received: from [10.57.9.136] (unknown [10.57.9.136]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 1516F3F70D; Wed, 16 Jun 2021 10:02:44 -0700 (PDT) Subject: Re: [PATCH v4 5/6] iommu/dma: Simplify calls to iommu_setup_dma_ops() To: Jean-Philippe Brucker , rjw@rjwysocki.net, lenb@kernel.org, joro@8bytes.org, mst@redhat.com References: <20210610075130.67517-1-jean-philippe@linaro.org> <20210610075130.67517-6-jean-philippe@linaro.org> From: Robin Murphy Message-ID: <6ce5fecb-fc81-5bf1-3577-6a09437b243e@arm.com> Date: Wed, 16 Jun 2021 18:02:39 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: <20210610075130.67517-6-jean-philippe@linaro.org> Content-Language: en-GB Cc: lorenzo.pieralisi@arm.com, eric.auger@redhat.com, catalin.marinas@arm.com, sudeep.holla@arm.com, virtualization@lists.linux-foundation.org, linux-acpi@vger.kernel.org, iommu@lists.linux-foundation.org, sebastien.boeuf@intel.com, guohanjun@huawei.com, will@kernel.org, dwmw2@infradead.org, linux-arm-kernel@lists.infradead.org, baolu.lu@linux.intel.com X-BeenThere: virtualization@lists.linux-foundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Linux virtualization 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: virtualization-bounces@lists.linux-foundation.org Sender: "Virtualization" On 2021-06-10 08:51, Jean-Philippe Brucker wrote: > dma-iommu uses the address bounds described in domain->geometry during > IOVA allocation. The address size parameters of iommu_setup_dma_ops() > are useful for describing additional limits set by the platform > firmware, but aren't needed for drivers that call this function from > probe_finalize(). The base parameter can be zero because dma-iommu > already removes the first IOVA page, and the limit parameter can be > U64_MAX because it's only checked against the domain geometry. Simplify > calls to iommu_setup_dma_ops(). > > Signed-off-by: Jean-Philippe Brucker > --- > drivers/iommu/amd/iommu.c | 9 +-------- > drivers/iommu/dma-iommu.c | 4 +++- > drivers/iommu/intel/iommu.c | 10 +--------- > 3 files changed, 5 insertions(+), 18 deletions(-) > > diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c > index 94b96d81fcfd..d3123bc05c08 100644 > --- a/drivers/iommu/amd/iommu.c > +++ b/drivers/iommu/amd/iommu.c > @@ -1708,14 +1708,7 @@ static struct iommu_device *amd_iommu_probe_device(struct device *dev) > > static void amd_iommu_probe_finalize(struct device *dev) > { > - struct iommu_domain *domain; > - > - /* Domains are initialized for this device - have a look what we ended up with */ > - domain = iommu_get_domain_for_dev(dev); > - if (domain->type == IOMMU_DOMAIN_DMA) > - iommu_setup_dma_ops(dev, IOVA_START_PFN << PAGE_SHIFT, U64_MAX); > - else > - set_dma_ops(dev, NULL); > + iommu_setup_dma_ops(dev, 0, U64_MAX); > } > > static void amd_iommu_release_device(struct device *dev) > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index c62e19bed302..175f8eaeb5b3 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -1322,7 +1322,9 @@ void iommu_setup_dma_ops(struct device *dev, u64 dma_base, u64 dma_limit) > if (domain->type == IOMMU_DOMAIN_DMA) { > if (iommu_dma_init_domain(domain, dma_base, dma_limit, dev)) > goto out_err; > - dev->dma_ops = &iommu_dma_ops; > + set_dma_ops(dev, &iommu_dma_ops); > + } else { > + set_dma_ops(dev, NULL); I'm not keen on moving this here, since iommu-dma only knows that its own ops are right for devices it *is* managing; it can't assume any particular ops are appropriate for devices it isn't. The idea here is that arch_setup_dma_ops() may have already set the appropriate ops for the non-IOMMU case, so if the default domain type is passthrough then we leave those in place. For example, I do still plan to revisit my conversion of arch/arm someday, at which point I'd have to undo this for that reason. Simplifying the base and size arguments is of course fine, but TBH I'd say rip the whole bloody lot out of the arch_setup_dma_ops() flow now. It's a considerable faff passing them around for nothing but a tenuous sanity check in iommu_dma_init_domain(), and now that dev->dma_range_map is a common thing we should expect that to give us any relevant limitations if we even still care. That said, those are all things which can be fixed up later if the series is otherwise ready to go and there's still a chance of landing it for 5.14. If you do have any other reason to respin, then I think the x86 probe_finalize functions simply want an unconditional set_dma_ops(dev, NULL) before the iommu_setup_dma_ops() call. Cheers, Robin. > } > > return; > diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c > index 85f18342603c..8d866940692a 100644 > --- a/drivers/iommu/intel/iommu.c > +++ b/drivers/iommu/intel/iommu.c > @@ -5165,15 +5165,7 @@ static void intel_iommu_release_device(struct device *dev) > > static void intel_iommu_probe_finalize(struct device *dev) > { > - dma_addr_t base = IOVA_START_PFN << VTD_PAGE_SHIFT; > - struct iommu_domain *domain = iommu_get_domain_for_dev(dev); > - struct dmar_domain *dmar_domain = to_dmar_domain(domain); > - > - if (domain && domain->type == IOMMU_DOMAIN_DMA) > - iommu_setup_dma_ops(dev, base, > - __DOMAIN_MAX_ADDR(dmar_domain->gaw)); > - else > - set_dma_ops(dev, NULL); > + iommu_setup_dma_ops(dev, 0, U64_MAX); > } > > static void intel_iommu_get_resv_regions(struct device *device, > _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization