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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 45CB0C4338F for ; Fri, 13 Aug 2021 07:44:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26464610A4 for ; Fri, 13 Aug 2021 07:44:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239663AbhHMHoc (ORCPT ); Fri, 13 Aug 2021 03:44:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239652AbhHMHoA (ORCPT ); Fri, 13 Aug 2021 03:44:00 -0400 Received: from mail-pl1-x635.google.com (mail-pl1-x635.google.com [IPv6:2607:f8b0:4864:20::635]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C559DC06122E for ; Fri, 13 Aug 2021 00:42:56 -0700 (PDT) Received: by mail-pl1-x635.google.com with SMTP id a20so10853732plm.0 for ; Fri, 13 Aug 2021 00:42:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=tBsX0MVHwtbJoJcOekTIeXMGpx0HIEfEiJde7/PcK80=; b=OmALWYXMW8a4RIeVEpkPuSzowOM17UfLHCl7A8woHWDiUnqiMEb/dnd9S9b9OfPDDh pFQOxURfwi4vrcRQsb3n5uFdBlbwXlnXgdiRXUsSM6V3CnRYoWmBU/UNv8dC1DURp/Io 35X3hEW1qK3Y9Hb3FLtbu/OVA9dCGRkbT4WnI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=tBsX0MVHwtbJoJcOekTIeXMGpx0HIEfEiJde7/PcK80=; b=XhbcPDoczg+tsKmVwyb0B8do80mTyxl+cAGhdtkj61h/dSwQxJofnpo2w8VRTr04wJ cexJruxOm4hFE5zcBgXgmi1Vo49xJZzG+PMGdPMEkmREsGAzDSOSe3P2a+R571fR85ei NHJcTx5GzF+hPKMUSDQSv8OS0XDLwatA5mC102uDbmnLrT+c0usIH4WiLDlt7rucvqsK BWs9yem2xAh9DXDvWccebSxciBXEO9vHUPLCP6KiY+aBLZ5ClHf/m7GiLUHCVJp1++gH lUVhSrhF4sACZST4DQwtcuEXhX9+LpT/osDFli/bBM8blBpVEXSpueCWNG3yFGn6ICMv l78g== X-Gm-Message-State: AOAM532SH6BTBXbO7I1ih+aGJEqTwcAq9e2L1OH7M4u6NCup+dzGeLDW kkkfzeBImZkO0uk1Ck20ZgcHhA== X-Google-Smtp-Source: ABdhPJx4DgrNW9FkJnyV1CwX0zsYlc9O2kkn4hO3RVn6NxwFOFMmSXfXqcLcSPIXABh5/bAjaFy84g== X-Received: by 2002:a63:594e:: with SMTP id j14mr1181232pgm.249.1628840576305; Fri, 13 Aug 2021 00:42:56 -0700 (PDT) Received: from localhost ([2401:fa00:8f:203:cbc8:5998:527e:5f43]) by smtp.gmail.com with UTF8SMTPSA id nn18sm640606pjb.21.2021.08.13.00.42.54 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 13 Aug 2021 00:42:55 -0700 (PDT) From: David Stevens X-Google-Original-From: David Stevens To: Robin Murphy , Christoph Hellwig Cc: Joerg Roedel , Will Deacon , Lu Baolu , Tom Murphy , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, David Stevens Subject: [PATCH v4 6/6] dma-iommu: account for min_align_mask Date: Fri, 13 Aug 2021 16:38:39 +0900 Message-Id: <20210813073839.1562438-7-stevensd@google.com> X-Mailer: git-send-email 2.33.0.rc1.237.g0d66db33f3-goog In-Reply-To: <20210813073839.1562438-1-stevensd@google.com> References: <20210813073839.1562438-1-stevensd@google.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David Stevens For devices which set min_align_mask, swiotlb preserves the offset of the original physical address within that mask. Since __iommu_dma_map accounts for non-aligned addresses, passing a non-aligned swiotlb address with the swiotlb aligned size results in the offset being accounted for twice in the size passed to iommu_map_atomic. The extra page exposed to DMA is also not cleaned up by __iommu_dma_unmap, since that function unmaps with the correct size. This causes mapping failures if the iova gets reused, due to collisions in the iommu page tables. To fix this, pass the original size to __iommu_dma_map, since that function already handles alignment. Additionally, when swiotlb returns non-aligned addresses, there is padding at the start of the bounce buffer that needs to be cleared. Fixes: 1f221a0d0dbf ("swiotlb: respect min_align_mask") Signed-off-by: David Stevens --- drivers/iommu/dma-iommu.c | 24 +++++++++++++----------- 1 file changed, 13 insertions(+), 11 deletions(-) diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index b1b0327cc2f6..b44b367839c2 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -788,7 +788,6 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, struct iommu_domain *domain = iommu_get_dma_domain(dev); struct iommu_dma_cookie *cookie = domain->iova_cookie; struct iova_domain *iovad = &cookie->iovad; - size_t aligned_size = size; dma_addr_t iova, dma_mask = dma_get_mask(dev); /* @@ -797,8 +796,8 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, */ if (IS_ENABLED(CONFIG_SWIOTLB) && dev_use_swiotlb(dev) && iova_offset(iovad, phys | size)) { - void *padding_start; - size_t padding_size; + void *tlb_start; + size_t aligned_size, iova_off, mapping_end_off; aligned_size = iova_align(iovad, size); phys = swiotlb_tbl_map_single(dev, phys, size, aligned_size, @@ -807,24 +806,27 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, if (phys == DMA_MAPPING_ERROR) return DMA_MAPPING_ERROR; - /* Cleanup the padding area. */ - padding_start = phys_to_virt(phys); - padding_size = aligned_size; + iova_off = iova_offset(iovad, phys); + tlb_start = phys_to_virt(phys - iova_off); if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) && (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) { - padding_start += size; - padding_size -= size; + /* Cleanup the padding area. */ + mapping_end_off = iova_off + size; + memset(tlb_start, 0, iova_off); + memset(tlb_start + mapping_end_off, 0, + aligned_size - mapping_end_off); + } else { + /* Nothing was sync'ed, so clear the whole buffer. */ + memset(tlb_start, 0, aligned_size); } - - memset(padding_start, 0, padding_size); } if (!coherent && !(attrs & DMA_ATTR_SKIP_CPU_SYNC)) arch_sync_dma_for_device(phys, size, dir); - iova = __iommu_dma_map(dev, phys, aligned_size, prot, dma_mask); + iova = __iommu_dma_map(dev, phys, size, prot, dma_mask); if (iova == DMA_MAPPING_ERROR && is_swiotlb_buffer(phys)) swiotlb_tbl_unmap_single(dev, phys, size, dir, attrs); return iova; -- 2.33.0.rc1.237.g0d66db33f3-goog