From patchwork Fri Jun 19 10:36:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Szyprowski X-Patchwork-Id: 11613817 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 7273690 for ; Fri, 19 Jun 2020 10:38:51 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 4EA9C208B8 for ; Fri, 19 Jun 2020 10:38:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="VHefC+Jl" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4EA9C208B8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=samsung.com Authentication-Results: mail.kernel.org; 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Fri, 19 Jun 2020 10:37:09 +0000 (GMT) X-AuditID: cbfec7f4-677ff7000000176d-fa-5eec95557eb9 Received: from eusmtip2.samsung.com ( [203.254.199.222]) by eusmgms2.samsung.com (EUCPMTA) with SMTP id 03.1B.06017.5559CEE5; Fri, 19 Jun 2020 11:37:09 +0100 (BST) Received: from AMDC2765.digital.local (unknown [106.120.51.73]) by eusmtip2.samsung.com (KnoxPortal) with ESMTPA id 20200619103708eusmtip20f150a4cbcaa1a29d802f5e72289a3ee~Z66MCpa440111401114eusmtip2N; Fri, 19 Jun 2020 10:37:08 +0000 (GMT) From: Marek Szyprowski To: dri-devel@lists.freedesktop.org, iommu@lists.linux-foundation.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org Subject: [PATCH v7 24/36] drm: xen: fix common struct sg_table related issues Date: Fri, 19 Jun 2020 12:36:24 +0200 Message-Id: <20200619103636.11974-25-m.szyprowski@samsung.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200619103636.11974-1-m.szyprowski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFtrJKsWRmVeSWpSXmKPExsWy7djPc7qhU9/EGbTPVLPoPXeSyWLjjPWs Fv+3TWS2uPL1PZvFytVHmSwW7Le2+HLlIZPFpsfXWC0u75rDZrH2yF12iw+r37NaHPzwhNXi +5bJTA68HmvmrWH0uLN0J6PH3m8LWDy2f3vA6nG/+ziTx+Yl9R63/z1m9ph8Yzmjx+EPV1g8 dt9sYPPo27KK0ePzJrkAnigum5TUnMyy1CJ9uwSujL1d7UwFfXwV0y82MzYwvuXuYuTkkBAw kTjxYDFbFyMXh5DACkaJvmezWSCcL4wSTxZNZYdwPjNKbN1wCaiMA6zl5XVziPhyRolr736y gowC6/h0SBHEZhMwlOh628UGYosItDJKnOjlAWlgFvjBJHFu2Ql2kISwgL9Ew7+HjCBDWQRU JfZtlQEJ8wrYSXy5foMd4jx5idUbDjCD2JxA8dctB1kh4pfYJSZNlYGwXST6HjyHqheWeHV8 C5QtI3F6cg/YNxICzYwSD8+tZYdwehglLjfNYISospa4c+4X2GfMApoS63fpQ4QdJbbuOsoM 8TCfxI23giBhZiBz0rbpUGFeiY42IYhqNYlZx9fBrT144RIzhO0h0ToZ5ENQWE1klOhf/oB5 AqP8LIRlCxgZVzGKp5YW56anFhvlpZbrFSfmFpfmpesl5+duYgQmqNP/jn/ZwbjrT9IhRgEO RiUe3hchr+OEWBPLiitzDzFKcDArifA6nT0dJ8SbklhZlVqUH19UmpNafIhRmoNFSZzXeNHL WCGB9MSS1OzU1ILUIpgsEwenVANjH6doi+B3Ww2Tp/s6C3QZzxm8qjzYXvNOXWRum2pUd2/W zxS/t390RTPrts7KS1OLfrpMpK1Xa/fxTXlFDgosQtdv3Li98fSe6CzdmTxar1XltXWfJEs+ VDnxPmwZQ9VXyad+3c9LFv8tZ+jYnrakUe7r6RuMn+/ESby6LpegcZvxz1bD6eFKLMUZiYZa zEXFiQAV/hk2TAMAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprNIsWRmVeSWpSXmKPExsVy+t/xe7qhU9/EGRzs5rPoPXeSyWLjjPWs Fv+3TWS2uPL1PZvFytVHmSwW7Le2+HLlIZPFpsfXWC0u75rDZrH2yF12iw+r37NaHPzwhNXi +5bJTA68HmvmrWH0uLN0J6PH3m8LWDy2f3vA6nG/+ziTx+Yl9R63/z1m9ph8Yzmjx+EPV1g8 dt9sYPPo27KK0ePzJrkAnig9m6L80pJUhYz84hJbpWhDCyM9Q0sLPSMTSz1DY/NYKyNTJX07 m5TUnMyy1CJ9uwS9jL1d7UwFfXwV0y82MzYwvuXuYuTgkBAwkXh53byLkYtDSGApo8SHW9tY uhg5geIyEienNbBC2MISf651sYHYQgKfGCXOz2cGsdkEDCW63oLEuThEBDoZJaZ1f2QHcZgF /jFJnNi7nQmkSljAV+Lwmz2MINtYBFQl9m2VAQnzCthJfLl+gx1igbzE6g0HwIZyAsVftxxk hVhmK7F8wXvmCYx8CxgZVjGKpJYW56bnFhvpFSfmFpfmpesl5+duYgRGzLZjP7fsYOx6F3yI UYCDUYmH90XI6zgh1sSy4srcQ4wSHMxKIrxOZ0/HCfGmJFZWpRblxxeV5qQWH2I0BbppIrOU aHI+MJrzSuINTQ3NLSwNzY3Njc0slMR5OwQOxggJpCeWpGanphakFsH0MXFwSjUwlmusllia NLd7y62CFuePloqXituO9YR6/ZO6rzIt21juU8GFFSfZL/efrg2oSN8tMuGiU8KrcJn2FkUb gQf9M9+3Opyq+8+745SblW2lyrO6l009Fz4tftktE/BzpZfBkvCZy1WUK39+MTYv/OEwZe/v sqo3E1I2blmcn6KqqxvGx3K/5mKvEktxRqKhFnNRcSIAGXz7bK4CAAA= X-CMS-MailID: 20200619103709eucas1p12c32fa6377caf78e5dc28ce0ff51e7a0 X-Msg-Generator: CA X-RootMTR: 20200619103709eucas1p12c32fa6377caf78e5dc28ce0ff51e7a0 X-EPHeader: CA CMS-TYPE: 201P X-CMS-RootMailID: 20200619103709eucas1p12c32fa6377caf78e5dc28ce0ff51e7a0 References: <20200619103636.11974-1-m.szyprowski@samsung.com> X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Bartlomiej Zolnierkiewicz , David Airlie , Oleksandr Andrushchenko , Daniel Vetter , xen-devel@lists.xenproject.org, Robin Murphy , Christoph Hellwig , linux-arm-kernel@lists.infradead.org, Marek Szyprowski Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function returns the number of the created entries in the DMA address space. However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and dma_unmap_sg must be called with the original number of the entries passed to the dma_map_sg(). struct sg_table is a common structure used for describing a non-contiguous memory buffer, used commonly in the DRM and graphics subsystems. It consists of a scatterlist with memory pages and DMA addresses (sgl entry), as well as the number of scatterlist entries: CPU pages (orig_nents entry) and DMA mapped pages (nents entry). It turned out that it was a common mistake to misuse nents and orig_nents entries, calling DMA-mapping functions with a wrong number of entries or ignoring the number of mapped entries returned by the dma_map_sg() function. Fix the code to refer to proper nents or orig_nents entries. This driver reports the number of the pages in the imported scatterlist, so it should refer to sg_table->orig_nents entry. Signed-off-by: Marek Szyprowski Acked-by: Oleksandr Andrushchenko --- drivers/gpu/drm/xen/xen_drm_front_gem.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/xen/xen_drm_front_gem.c b/drivers/gpu/drm/xen/xen_drm_front_gem.c index f0b85e094111..ba4bdc5590ea 100644 --- a/drivers/gpu/drm/xen/xen_drm_front_gem.c +++ b/drivers/gpu/drm/xen/xen_drm_front_gem.c @@ -215,7 +215,7 @@ xen_drm_front_gem_import_sg_table(struct drm_device *dev, return ERR_PTR(ret); DRM_DEBUG("Imported buffer of size %zu with nents %u\n", - size, sgt->nents); + size, sgt->orig_nents); return &xen_obj->base; } From patchwork Fri Jun 19 10:36:25 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Szyprowski X-Patchwork-Id: 11613821 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1AC1590 for ; Fri, 19 Jun 2020 10:39:00 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 EB886208B8 for ; 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Fri, 19 Jun 2020 10:37:09 +0000 (GMT) From: Marek Szyprowski To: dri-devel@lists.freedesktop.org, iommu@lists.linux-foundation.org, linaro-mm-sig@lists.linaro.org, linux-kernel@vger.kernel.org Subject: [PATCH v7 25/36] xen: gntdev: fix common struct sg_table related issues Date: Fri, 19 Jun 2020 12:36:25 +0200 Message-Id: <20200619103636.11974-26-m.szyprowski@samsung.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200619103636.11974-1-m.szyprowski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFjrMKsWRmVeSWpSXmKPExsWy7djPc7phU9/EGTQ+ErPoPXeSyWLjjPWs Fhent7JY/N82kdniytf3bBYrVx9lsliw39pizk0jiy9XHjJZbHp8jdXi8q45bBZrj9xltzj4 4Qmrxfctk5kc+DzWzFvD6LH32wIWj+3fHrB63O8+zuSxeUm9x+1/j5k9Jt9Yzuhx+MMVFo/d NxvYPD4+vcXi0bdlFaPH+i1XWTw+b5IL4I3isklJzcksSy3St0vgylh/4xJLwUmxivdbdrM0 MG4R6mLk4JAQMJFYspSni5GLQ0hgBaPEk5OLmCGcL4wSzxfuYYdwPjNKbJ3/EijDCdYxc8cZ qMRyRol9rc8Y4VoObd/DBlLFJmAo0fW2C8wWEWhllDjRC7aEWaCbWWLq2lWsIAlhgSCJm1dO gRWxCKhKbO5ZyQ5i8wrYSdz5fZ4VYp28xOoNB8BWcwLFX7cchIrfY5f4810fwnaRuHz5EhOE LSzx6vgWdghbRuL05B4WkMUSAs2MEg/PrWWHcHoYJS43zWCEqLKWuHPuFxsoOJgFNCXW79KH hIyjxLb2JAiTT+LGW0GQYmYgc9K26cwQYV6JjjYhiBlqErOOr4PbevDCJWhgeUjsOreIFRI+ ExklWk81sE1glJ+FsGsBI+MqRvHU0uLc9NRi47zUcr3ixNzi0rx0veT83E2MwKR1+t/xrzsY 9/1JOsQowMGoxMP7IuR1nBBrYllxZe4hRgkOZiURXqezp+OEeFMSK6tSi/Lji0pzUosPMUpz sCiJ8xovehkrJJCeWJKanZpakFoEk2Xi4JRqYLwT/ipGNpPvOOvPqRvf2Om+fMrheqTk+OfG C8VibYFHdjT12zinPnt5S9z5gpPui09HrGU2tn/UeelfGLT7f2/Wx1UJe1i93Zz4Juf4H9t4 0XnOgjrZozxr3wcv5vrRua7b7lkg5x1ZkZ87Z6Vw8PrwVSzXXB2rHTnN7F16wevZ62Iue7w/ lKXEUpyRaKjFXFScCAAwPjcEVgMAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFlrGIsWRmVeSWpSXmKPExsVy+t/xe7qhU9/EGTx5bmnRe+4kk8XGGetZ LS5Ob2Wx+L9tIrPFla/v2SxWrj7KZLFgv7XFnJtGFl+uPGSy2PT4GqvF5V1z2CzWHrnLbnHw wxNWi+9bJjM58HmsmbeG0WPvtwUsHtu/PWD1uN99nMlj85J6j9v/HjN7TL6xnNHj8IcrLB67 bzaweXx8eovFo2/LKkaP9Vuusnh83iQXwBulZ1OUX1qSqpCRX1xiqxRtaGGkZ2hpoWdkYqln aGwea2VkqqRvZ5OSmpNZllqkb5egl7H+xiWWgpNiFe+37GZpYNwi1MXIySEhYCIxc8cZ9i5G Lg4hgaWMEhd+LmWESMhInJzWwAphC0v8udbFBlH0iVHi2KUTbCAJNgFDia63EAkRgU5GiWnd H8FGMQtMZpZ4tvo6UxcjB4ewQIBEX2MVSAOLgKrE5p6V7CA2r4CdxJ3f56E2yEus3nCAGcTm BIq/bjkIFhcSsJVYvuA98wRGvgWMDKsYRVJLi3PTc4sN9YoTc4tL89L1kvNzNzEC42jbsZ+b dzBe2hh8iFGAg1GJh/dFyOs4IdbEsuLK3EOMEhzMSiK8TmdPxwnxpiRWVqUW5ccXleakFh9i NAU6aiKzlGhyPjDG80riDU0NzS0sDc2NzY3NLJTEeTsEDsYICaQnlqRmp6YWpBbB9DFxcEo1 MAYtmJk782PZ2r5F3zsVHNIjv+Yu3Xu89pmp2/9nkfUX1sz6tKHq/P6wz6erXv9b7VFlqM9l 4nT46qrvrT8vHhLTU3jNlHIgfafeCYFoj0/u7udYuO96SC4qVv/55vWEKb7di+ZOETjhp6Nv vzb50zlu4+NFZgyz0iPcC1ZvnXRq6WKeLcDQiVNiKc5INNRiLipOBABev5EouQIAAA== X-CMS-MailID: 20200619103710eucas1p1873c8ebb37e6717a5864c31d10b50efd X-Msg-Generator: CA X-RootMTR: 20200619103710eucas1p1873c8ebb37e6717a5864c31d10b50efd X-EPHeader: CA CMS-TYPE: 201P X-CMS-RootMailID: 20200619103710eucas1p1873c8ebb37e6717a5864c31d10b50efd References: <20200619103636.11974-1-m.szyprowski@samsung.com> X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Juergen Gross , Bartlomiej Zolnierkiewicz , David Airlie , Daniel Vetter , xen-devel@lists.xenproject.org, Boris Ostrovsky , Robin Murphy , Christoph Hellwig , linux-arm-kernel@lists.infradead.org, Marek Szyprowski Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" The Documentation/DMA-API-HOWTO.txt states that the dma_map_sg() function returns the number of the created entries in the DMA address space. However the subsequent calls to the dma_sync_sg_for_{device,cpu}() and dma_unmap_sg must be called with the original number of the entries passed to the dma_map_sg(). struct sg_table is a common structure used for describing a non-contiguous memory buffer, used commonly in the DRM and graphics subsystems. It consists of a scatterlist with memory pages and DMA addresses (sgl entry), as well as the number of scatterlist entries: CPU pages (orig_nents entry) and DMA mapped pages (nents entry). It turned out that it was a common mistake to misuse nents and orig_nents entries, calling DMA-mapping functions with a wrong number of entries or ignoring the number of mapped entries returned by the dma_map_sg() function. To avoid such issues, lets use a common dma-mapping wrappers operating directly on the struct sg_table objects and use scatterlist page iterators where possible. This, almost always, hides references to the nents and orig_nents entries, making the code robust, easier to follow and copy/paste safe. Signed-off-by: Marek Szyprowski Acked-by: Juergen Gross --- drivers/xen/gntdev-dmabuf.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/drivers/xen/gntdev-dmabuf.c b/drivers/xen/gntdev-dmabuf.c index 75d3bb948bf3..ba6cad871568 100644 --- a/drivers/xen/gntdev-dmabuf.c +++ b/drivers/xen/gntdev-dmabuf.c @@ -247,10 +247,9 @@ static void dmabuf_exp_ops_detach(struct dma_buf *dma_buf, if (sgt) { if (gntdev_dmabuf_attach->dir != DMA_NONE) - dma_unmap_sg_attrs(attach->dev, sgt->sgl, - sgt->nents, - gntdev_dmabuf_attach->dir, - DMA_ATTR_SKIP_CPU_SYNC); + dma_unmap_sgtable(attach->dev, sgt, + gntdev_dmabuf_attach->dir, + DMA_ATTR_SKIP_CPU_SYNC); sg_free_table(sgt); } @@ -288,8 +287,8 @@ dmabuf_exp_ops_map_dma_buf(struct dma_buf_attachment *attach, sgt = dmabuf_pages_to_sgt(gntdev_dmabuf->pages, gntdev_dmabuf->nr_pages); if (!IS_ERR(sgt)) { - if (!dma_map_sg_attrs(attach->dev, sgt->sgl, sgt->nents, dir, - DMA_ATTR_SKIP_CPU_SYNC)) { + if (dma_map_sgtable(attach->dev, sgt, dir, + DMA_ATTR_SKIP_CPU_SYNC)) { sg_free_table(sgt); kfree(sgt); sgt = ERR_PTR(-ENOMEM); @@ -625,7 +624,7 @@ dmabuf_imp_to_refs(struct gntdev_dmabuf_priv *priv, struct device *dev, /* Now convert sgt to array of pages and check for page validity. */ i = 0; - for_each_sg_page(sgt->sgl, &sg_iter, sgt->nents, 0) { + for_each_sgtable_page(sgt, &sg_iter, 0) { struct page *page = sg_page_iter_page(&sg_iter); /* * Check if page is valid: this can happen if we are given