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=ham 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 36948C4320A for ; Tue, 17 Aug 2021 01:39:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1FA5960EAF for ; Tue, 17 Aug 2021 01:39:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236777AbhHQBkU (ORCPT ); Mon, 16 Aug 2021 21:40:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50266 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236345AbhHQBkQ (ORCPT ); Mon, 16 Aug 2021 21:40:16 -0400 Received: from mail-pl1-x62a.google.com (mail-pl1-x62a.google.com [IPv6:2607:f8b0:4864:20::62a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 894A8C0613CF for ; Mon, 16 Aug 2021 18:39:42 -0700 (PDT) Received: by mail-pl1-x62a.google.com with SMTP id q2so22843983plr.11 for ; Mon, 16 Aug 2021 18:39:42 -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=q9XB86DIe6440U7Wgn53Q54Y7DGoSwATnF9snUA3Icc=; b=TuSFkK3uO0HniVv/r5ufTbTIiD3OJgHt1f5UO/HGLUtUckfYJ+OPELuyBrA+OqWjo5 CyOGnh5lvCuk0t1/E7DOv3nPDLz/1cpWnAZ5EEoQTgniXPH2/FQN3LG/rjbw7JveSUv4 hdmmaxvK2Vnh+6DRY8Q/a+PxkU2Xz2m9P4xSo= 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=q9XB86DIe6440U7Wgn53Q54Y7DGoSwATnF9snUA3Icc=; b=UgHeRXErnxlUwTs0SIxCtgg6eMg5Bf+5jKmrUoEkPrUrKP8xlSBeH9xtomfeKfiwXT VSja3dpnLVFPnCZr2Vi6xPVyA8O/o9AQgCKQea4bpJ+3TDB7EWcQhaC2GUbcRAIioNPC QXjZdOjw33whd3BpXvSs+4iEi8cS8L+an9zWzf/DHvPaJtCikMk4Zf+0dNUBhF2uYjg9 4PQRpnXBAVpTsD6XTMG+0nY9G3TY10+c1+zzdpjc8phCMfj6gBwgeAJuZuajtmo6Sqgg Y7O9m3yiBlrfYknsJQht//ji3vrmAHHmqwO02z06TUYT4jA8eDQLBzLlL4k/GNjJ46gx FdmA== X-Gm-Message-State: AOAM531tgxJ4jHzptYGiFM+3DUR2ktkxKEy9/IpkS9e2kIXdizb2KZRj +nwP+VY4LihYK21Hgw14krwZ9A== X-Google-Smtp-Source: ABdhPJziVMZGAz3+/7NmsxzmGWn1PVMenahFvVaOfrANZvx0kOhStJye2gVjIh1y+8PDzwytb9iAwg== X-Received: by 2002:a17:90a:cf8e:: with SMTP id i14mr870389pju.136.1629164382105; Mon, 16 Aug 2021 18:39:42 -0700 (PDT) Received: from localhost ([2401:fa00:8f:203:6864:767c:2ff8:749d]) by smtp.gmail.com with UTF8SMTPSA id l14sm331970pjq.13.2021.08.16.18.39.40 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 16 Aug 2021 18:39:41 -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 v6 7/7] dma-iommu: account for min_align_mask Date: Tue, 17 Aug 2021 10:38:52 +0900 Message-Id: <20210817013852.3222824-8-stevensd@google.com> X-Mailer: git-send-email 2.33.0.rc1.237.g0d66db33f3-goog In-Reply-To: <20210817013852.3222824-1-stevensd@google.com> References: <20210817013852.3222824-1-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 6738420fc081..f2fb360c2907 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); /* @@ -796,8 +795,8 @@ static dma_addr_t iommu_dma_map_page(struct device *dev, struct page *page, * page aligned, we don't need to use a bounce page. */ if (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, @@ -806,23 +805,26 @@ 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