From patchwork Tue Jul 10 17:17:19 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Robin Murphy X-Patchwork-Id: 10517915 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4CA9E603D7 for ; Tue, 10 Jul 2018 18:43:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 442C026B39 for ; Tue, 10 Jul 2018 18:43:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 383B029200; Tue, 10 Jul 2018 18:43:33 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D8E0F26B39 for ; Tue, 10 Jul 2018 18:43:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389006AbeGJSdm (ORCPT ); Tue, 10 Jul 2018 14:33:42 -0400 Received: from foss.arm.com ([217.140.101.70]:51800 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732681AbeGJSdm (ORCPT ); Tue, 10 Jul 2018 14:33:42 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 044811713; Tue, 10 Jul 2018 10:17:39 -0700 (PDT) Received: from e110467-lin.cambridge.arm.com (e110467-lin.cambridge.arm.com [10.1.210.23]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 751F63F589; Tue, 10 Jul 2018 10:17:36 -0700 (PDT) From: Robin Murphy To: hch@lst.de, m.szyprowski@samsung.com, iommu@lists.linux-foundation.org Cc: linux-arm-kernel@lists.infradead.org, linux-acpi@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, lorenzo.pieralisi@arm.com, hanjun.guo@linaro.org, sudeep.holla@arm.com, robh+dt@kernel.org, frowand.list@gmail.com, gregkh@linuxfoundation.org, joro@8bytes.org, x86@kernel.org Subject: [RFC PATCH 4/4] iommu/dma: Respect bus DMA limit for IOVAs Date: Tue, 10 Jul 2018 18:17:19 +0100 Message-Id: <2c0d7437ee7ccdd58da25faa283bd3c3148b961b.1531239284.git.robin.murphy@arm.com> X-Mailer: git-send-email 2.17.1.dirty In-Reply-To: References: Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Take the new bus limit into account (when present) for IOVA allocations, to accommodate those SoCs which integrate off-the-shelf IP blocks with narrower interconnects such that the link between a device output and an IOMMU input can truncate DMA addresses to even fewer bits than the native size of either block's interface would imply. Eventually it might make sense for the DMA core to apply this constraint up-front in dma_set_mask() and friends, but for now this seems like the least risky approach. Signed-off-by: Robin Murphy --- drivers/iommu/dma-iommu.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index ddcbbdb5d658..511ff9a1d6d9 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -367,6 +367,9 @@ static dma_addr_t iommu_dma_alloc_iova(struct iommu_domain *domain, if (iova_len < (1 << (IOVA_RANGE_CACHE_MAX_SIZE - 1))) iova_len = roundup_pow_of_two(iova_len); + if (dev->bus_dma_mask) + dma_limit &= dev->bus_dma_mask; + if (domain->geometry.force_aperture) dma_limit = min(dma_limit, domain->geometry.aperture_end);