From patchwork Wed May 13 13:32:08 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marek Szyprowski X-Patchwork-Id: 11546393 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 234B559D for ; Wed, 13 May 2020 13:47:09 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 36F68204EA for ; Wed, 13 May 2020 13:47:10 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="Cy3TayxL"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="VKrLxF3K" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 36F68204EA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=samsung.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=WFKTtd9bQ8OWYbO26y0thcW/1WVM0xBoHHffmZ2CwQ4=; b=Cy3TayxLXZ0ReDL4lndZ/WGv31 ieIy8QYfBK7VUQRa9KGJ7i9zYaM+kxveHKSgorS10ucS9obshjsXLKbJ56tE1rveZHKWH84Fig+qF SV471goxPJXwlJxhULKYmRlesqyK7EclTWUYjvPXm1lOdVQhQwYgbF8nKg80ax4EQrDWoh2g4IhgQ NxdT0zgwk3NHgKS+cwyZKTQN7+rlAt8ZpMHZqjM5vdGcIRsz1wDD3gE06WsSsQzLaTx8ZhnUSOZC2 DTgODupLrA7FoTmcsC4PblgVo3qYOEGkYXMtuh+gkvI/iSkhVkay5NGkW0ok9GKpKZg1EN2zQG5gg bGWn1KAA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jYrVR-0001PF-2v; Wed, 13 May 2020 13:33:05 +0000 Received: from mailout2.w1.samsung.com ([210.118.77.12]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jYrVL-0001Kd-Rj for linux-arm-kernel@lists.infradead.org; Wed, 13 May 2020 13:33:02 +0000 Received: from eucas1p1.samsung.com (unknown [182.198.249.206]) by mailout2.w1.samsung.com (KnoxPortal) with ESMTP id 20200513133257euoutp02007f0b6716491de28e17546d8ca75ef1~OmcIiAKkP3216632166euoutp02g for ; Wed, 13 May 2020 13:32:57 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout2.w1.samsung.com 20200513133257euoutp02007f0b6716491de28e17546d8ca75ef1~OmcIiAKkP3216632166euoutp02g DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1589376777; bh=SMTxZNZpTSAf+VjaRdwIa7Y+Y92ELOA8MjwAFVO+Mus=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VKrLxF3KEiWmVZ1axlhSlzty0rd2nUqXsHuI7B7LU28r5TvCvsp+0bgDe4vtq9QOY WiKZcd124gvPVjK5otBDPFZ8OFs4Ng94v6RMIBwxoj8zDX9Eu+NKd2eBdrnLRwwAaZ 2zo3AcPWxR1hl6t0/nrmIY5WXFjlcZ6Vzn2OE+7A= Received: from eusmges1new.samsung.com (unknown [203.254.199.242]) by eucas1p1.samsung.com (KnoxPortal) with ESMTP id 20200513133257eucas1p1ab88f1465f6ce76a0c7f470a63001ea2~OmcIUwDTB0876608766eucas1p1h; Wed, 13 May 2020 13:32:57 +0000 (GMT) Received: from eucas1p1.samsung.com ( [182.198.249.206]) by eusmges1new.samsung.com (EUCPMTA) with SMTP id FD.B5.61286.907FBBE5; Wed, 13 May 2020 14:32:57 +0100 (BST) Received: from eusmtrp1.samsung.com (unknown [182.198.249.138]) by eucas1p2.samsung.com (KnoxPortal) with ESMTPA id 20200513133256eucas1p273110d0c8f67e52fc7385acef776efaa~OmcH5dMRP0359403594eucas1p2L; Wed, 13 May 2020 13:32:56 +0000 (GMT) Received: from eusmgms1.samsung.com (unknown [182.198.249.179]) by eusmtrp1.samsung.com (KnoxPortal) with ESMTP id 20200513133256eusmtrp11bf699394ab06f7b9d70d588c796f3dc~OmcH4xvA20994509945eusmtrp1W; Wed, 13 May 2020 13:32:56 +0000 (GMT) X-AuditID: cbfec7f2-ef1ff7000001ef66-28-5ebbf709f135 Received: from eusmtip1.samsung.com ( [203.254.199.221]) by eusmgms1.samsung.com (EUCPMTA) with SMTP id B7.0A.08375.807FBBE5; Wed, 13 May 2020 14:32:56 +0100 (BST) Received: from AMDC2765.digital.local (unknown [106.120.51.73]) by eusmtip1.samsung.com (KnoxPortal) with ESMTPA id 20200513133256eusmtip10a029b12870de4156e2e5b8913fad120~OmcHTRPCk2465024650eusmtip1_; Wed, 13 May 2020 13:32:56 +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 v5 01/38] dma-mapping: add generic helpers for mapping sgtable objects Date: Wed, 13 May 2020 15:32:08 +0200 Message-Id: <20200513133245.6408-1-m.szyprowski@samsung.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200513132114.6046-1-m.szyprowski@samsung.com> X-Brightmail-Tracker: H4sIAAAAAAAAA0VSa0hTYRju29nZzqbT45R80UyYJGSpSf04MLPCfpz+RAVZCpkrD2ptajte +6Moai0NL5XDUsS8OzUvaUzFHNkUaZSaTPOaFZbZwltYoG0erX/P7X2f7/v4CExajbsRMbEJ jDpWoZQJxPyO1xsmX9GvrvAjwzPOVJ5pkEe1aJtxaqujAKNG1ywCqq6hn0eV98qp1dE5HtU6 P4ZTI/onAqrx1ZSQ6vv5CT9pR+vKdIjuWS/n053rszg9c8/Io9sq0+gPm/MYXWSuQXTXeLqA vt9ej+iV1v3nxGHiwEhGGZPEqP2DIsTRedn1KL7JO+VBZjWejno8NUhEAHkMzMZapEFiQkrW IuhbsAhthpRcRTC4xeOMFQTlOj3anfg+t8znjBoEj+pKd4h1ouJ9Js+WEpABoFnSCGzYhcxC MJBnb8MYqeVB/2KiDTuTl6HMMLq9lU8egIovOsyGJWQgGAe0ONfmCQ3PXm7rIvI4LD/fwG1l QDYJ4anFaC0jrOQ0zLyhuLwzfDO2Czm8D4aKcvlcPhPBnKlRyJFcBCMZ2p37yGHS9FtgW4SR B6FZ78/Jp8BUqMe5/Q5gXnLizu8AhR3FGCdL4E62lEt7Q4mx6V9t39thjMM0tC+27bxiPoJ2 8yDKR54l/8vKEapHrkwiq4pi2IBYJtmPVajYxNgov+txqlZk/T1Dm8blF2ht+JoBkQSS2Uuo ia5wKa5IYlNVBgQEJnORnG22SpJIReptRh13VZ2oZFgDcif4MlfJ0YqvV6RklCKBuckw8Yx6 1+URIrd0hO9Jsp8oyDhx2P9jWkujV+g7cw3sveDhkdDL5FQ5uKvOB1eG6lLsSkM0d32TJmYV cWeSu8URh5zAyzF1hk3rnizOueW5EPRHqZ2XpGT/yCzqlVvknXaPLzo+ZNDspc35YGHVWOf0 Z33bjfGpwKy4kNaSaQsVUqca8MnNlYcVyfhstCLAB1Ozir/3t71COQMAAA== X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFupikeLIzCtJLcpLzFFi42I5/e/4XV2O77vjDCb9MbLoPXeSyWLjjPWs Fv+3TWS2uPL1PZvFytVHmSwW7Le2+HLlIZPFpsfXWC0u75rDZrH2yF12i4MfnrA6cHusmbeG 0WPvtwUsHtu/PWD1uN99nMlj85J6j9v/HjN7TL6xnNFj980GNo++LasYPT5vkgvgitKzKcov LUlVyMgvLrFVija0MNIztLTQMzKx1DM0No+1MjJV0rezSUnNySxLLdK3S9DL6G1bxViwTq1i SvMy1gbGvfJdjJwcEgImEm8efmLpYuTiEBJYyijxasFTVoiEjMTJaQ1QtrDEn2tdbBBFnxgl 3h14DpZgEzCU6HoLkRAR6GSUmNb9kR3EYRaYxySx6OEhdpAqYYEwiZ0ftoHZLAKqEouerWEG sXkFbCSOn5gBtUJeYvWGA2BxTgFbiU9bf4LFhYBq1rbOYZvAyLeAkWEVo0hqaXFuem6xoV5x Ym5xaV66XnJ+7iZGYDxsO/Zz8w7GSxuDDzEKcDAq8fBa3NodJ8SaWFZcmXuIUYKDWUmE1289 UIg3JbGyKrUoP76oNCe1+BCjKdBRE5mlRJPzgbGaVxJvaGpobmFpaG5sbmxmoSTO2yFwMEZI ID2xJDU7NbUgtQimj4mDU6qBMaSi692hcinJ34t2HWxjfe1+2VN/o1/Uu6n6q+MfJNzYYd+y f00hzz4Z6V1fjF4fPrAveW7xvIJpB6LWr0/nf+uv6ye37IqIcPXl83lKdwIYk5RO7boQpFHR sXx1oEHYzjvRWp+dGJ8EuNV/jedZ3idy947AAeGUS0fPXd6cFXHQk3/htv97piuxFGckGmox FxUnAgDvD09CnQIAAA== X-CMS-MailID: 20200513133256eucas1p273110d0c8f67e52fc7385acef776efaa X-Msg-Generator: CA X-RootMTR: 20200513133256eucas1p273110d0c8f67e52fc7385acef776efaa X-EPHeader: CA CMS-TYPE: 201P X-CMS-RootMailID: 20200513133256eucas1p273110d0c8f67e52fc7385acef776efaa References: <20200513132114.6046-1-m.szyprowski@samsung.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200513_063300_220461_B9A454D3 X-CRM114-Status: GOOD ( 16.93 ) X-Spam-Score: -5.2 (-----) X-Spam-Report: SpamAssassin version 3.4.4 on bombadil.infradead.org summary: Content analysis details: (-5.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [210.118.77.12 listed in list.dnswl.org] 0.0 RCVD_IN_MSPIKE_H3 RBL: Good reputation (+3) [210.118.77.12 listed in wl.mailspike.net] -0.0 SPF_HELO_PASS SPF: HELO matches SPF record -0.0 SPF_PASS SPF: sender matches SPF record -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.0 RCVD_IN_MSPIKE_WL Mailspike good senders -0.0 DKIMWL_WL_HIGH DKIMwl.org - Whitelisted High sender X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Bartlomiej Zolnierkiewicz , David Airlie , Daniel Vetter , Robin Murphy , Christoph Hellwig , linux-arm-kernel@lists.infradead.org, Marek Szyprowski MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org struct sg_table is a common structure used for describing a memory buffer. 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, let's introduce a common wrappers operating directly on the struct sg_table objects, which take care of the proper use of the nents and orig_nents entries. Signed-off-by: Marek Szyprowski Reviewed-by: Christoph Hellwig Reviewed-by: Robin Murphy --- For more information, see '[PATCH v5 00/38] DRM: fix struct sg_table nents vs. orig_nents misuse' thread: https://lore.kernel.org/linux-iommu/20200513132114.6046-1-m.szyprowski@samsung.com/T/ --- include/linux/dma-mapping.h | 78 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index b43116a..b50fe36 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -609,6 +609,84 @@ static inline void dma_sync_single_range_for_device(struct device *dev, return dma_sync_single_for_device(dev, addr + offset, size, dir); } +/** + * dma_map_sgtable - Map the given buffer for DMA + * @dev: The device for which to perform the DMA operation + * @sgt: The sg_table object describing the buffer + * @dir: DMA direction + * @attrs: Optional DMA attributes for the map operation + * + * Maps a buffer described by a scatterlist stored in the given sg_table + * object for the @dir DMA operation by the @dev device. After success + * the ownership for the buffer is transferred to the DMA domain. One has + * to call dma_sync_sgtable_for_cpu() or dma_unmap_sgtable() to move the + * ownership of the buffer back to the CPU domain before touching the + * buffer by the CPU. + * Returns 0 on success or -EINVAL on error during mapping the buffer. + */ +static inline int dma_map_sgtable(struct device *dev, struct sg_table *sgt, + enum dma_data_direction dir, unsigned long attrs) +{ + int n = dma_map_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs); + + if (n <= 0) + return -EINVAL; + sgt->nents = n; + return 0; +} + +/** + * dma_unmap_sgtable - Unmap the given buffer for DMA + * @dev: The device for which to perform the DMA operation + * @sgt: The sg_table object describing the buffer + * @dir: DMA direction + * @attrs: Optional DMA attributes for the unmap operation + * + * Unmaps a buffer described by a scatterlist stored in the given sg_table + * object for the @dir DMA operation by the @dev device. After this function + * the ownership of the buffer is transferred back to the CPU domain. + */ +static inline void dma_unmap_sgtable(struct device *dev, struct sg_table *sgt, + enum dma_data_direction dir, unsigned long attrs) +{ + dma_unmap_sg_attrs(dev, sgt->sgl, sgt->orig_nents, dir, attrs); +} + +/** + * dma_sync_sgtable_for_cpu - Synchronize the given buffer for CPU access + * @dev: The device for which to perform the DMA operation + * @sgt: The sg_table object describing the buffer + * @dir: DMA direction + * + * Performs the needed cache synchronization and moves the ownership of the + * buffer back to the CPU domain, so it is safe to perform any access to it + * by the CPU. Before doing any further DMA operations, one has to transfer + * the ownership of the buffer back to the DMA domain by calling the + * dma_sync_sgtable_for_device(). + */ +static inline void dma_sync_sgtable_for_cpu(struct device *dev, + struct sg_table *sgt, enum dma_data_direction dir) +{ + dma_sync_sg_for_cpu(dev, sgt->sgl, sgt->orig_nents, dir); +} + +/** + * dma_sync_sgtable_for_device - Synchronize the given buffer for DMA + * @dev: The device for which to perform the DMA operation + * @sgt: The sg_table object describing the buffer + * @dir: DMA direction + * + * Performs the needed cache synchronization and moves the ownership of the + * buffer back to the DMA domain, so it is safe to perform the DMA operation. + * Once finished, one has to call dma_sync_sgtable_for_cpu() or + * dma_unmap_sgtable(). + */ +static inline void dma_sync_sgtable_for_device(struct device *dev, + struct sg_table *sgt, enum dma_data_direction dir) +{ + dma_sync_sg_for_device(dev, sgt->sgl, sgt->orig_nents, dir); +} + #define dma_map_single(d, a, s, r) dma_map_single_attrs(d, a, s, r, 0) #define dma_unmap_single(d, a, s, r) dma_unmap_single_attrs(d, a, s, r, 0) #define dma_map_sg(d, s, n, r) dma_map_sg_attrs(d, s, n, r, 0)