From patchwork Mon Aug 17 15:16:29 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 266467 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=-9.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,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 5FE15C433DF for ; Mon, 17 Aug 2020 15:39:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 30F2822DD6 for ; Mon, 17 Aug 2020 15:39:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597678745; bh=0t5POLBWNfw7QFM1DJCV/inOcg3oxp4uCilRlsw1hfQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=MrqRf7OC8wO7oIoiwu0GIWFBN8dqm7HGgVz947LMgjwepyCIFDys9kegPUyLhaue7 NZjDBVXK+c47kfDYcZQ61p766DevvOWeTvOHHJcJTRd+LodQpJYlJT++yId6mgpK/L L6/YoZXTipRqmSSecMZCELkr/a97MtkkscMTXXDQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387434AbgHQPjD (ORCPT ); Mon, 17 Aug 2020 11:39:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:47280 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387424AbgHQPi6 (ORCPT ); Mon, 17 Aug 2020 11:38:58 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 5D3CC208E4; Mon, 17 Aug 2020 15:38:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597678735; bh=0t5POLBWNfw7QFM1DJCV/inOcg3oxp4uCilRlsw1hfQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=b9nzOz5G2VVDm5WjPtyT69/61bNgjBaYzJBLzBMSiuPdtFWwV5YIgBQqvFKNEuzWo CRaz4RNdTRGTutcQncWEYicMa5mmaUFcWYMf4GcEz/K+A9eQrgr+//hqhELFhDXFWn hL2rb/J5C79G+vRFaPF5wcaPcqSDNCb64r45GNh0= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christian Eggers , Mark Brown Subject: [PATCH 5.8 436/464] spi: spidev: Align buffers for DMA Date: Mon, 17 Aug 2020 17:16:29 +0200 Message-Id: <20200817143854.663083713@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817143833.737102804@linuxfoundation.org> References: <20200817143833.737102804@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Christian Eggers commit aa9e862d7d5bcecd4dca9f39e8b684b93dd84ee7 upstream. Simply copying all xfers from userspace into one bounce buffer causes alignment problems if the SPI controller uses DMA. Ensure that all transfer data blocks within the rx and tx bounce buffers are aligned for DMA (according to ARCH_KMALLOC_MINALIGN). Alignment may increase the usage of the bounce buffers. In some cases, the buffers may need to be increased using the "bufsiz" module parameter. Signed-off-by: Christian Eggers Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200728100832.24788-1-ceggers@arri.de Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- drivers/spi/spidev.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) --- a/drivers/spi/spidev.c +++ b/drivers/spi/spidev.c @@ -224,6 +224,11 @@ static int spidev_message(struct spidev_ for (n = n_xfers, k_tmp = k_xfers, u_tmp = u_xfers; n; n--, k_tmp++, u_tmp++) { + /* Ensure that also following allocations from rx_buf/tx_buf will meet + * DMA alignment requirements. + */ + unsigned int len_aligned = ALIGN(u_tmp->len, ARCH_KMALLOC_MINALIGN); + k_tmp->len = u_tmp->len; total += k_tmp->len; @@ -239,17 +244,17 @@ static int spidev_message(struct spidev_ if (u_tmp->rx_buf) { /* this transfer needs space in RX bounce buffer */ - rx_total += k_tmp->len; + rx_total += len_aligned; if (rx_total > bufsiz) { status = -EMSGSIZE; goto done; } k_tmp->rx_buf = rx_buf; - rx_buf += k_tmp->len; + rx_buf += len_aligned; } if (u_tmp->tx_buf) { /* this transfer needs space in TX bounce buffer */ - tx_total += k_tmp->len; + tx_total += len_aligned; if (tx_total > bufsiz) { status = -EMSGSIZE; goto done; @@ -259,7 +264,7 @@ static int spidev_message(struct spidev_ (uintptr_t) u_tmp->tx_buf, u_tmp->len)) goto done; - tx_buf += k_tmp->len; + tx_buf += len_aligned; } k_tmp->cs_change = !!u_tmp->cs_change; @@ -293,16 +298,16 @@ static int spidev_message(struct spidev_ goto done; /* copy any rx data out of bounce buffer */ - rx_buf = spidev->rx_buffer; - for (n = n_xfers, u_tmp = u_xfers; n; n--, u_tmp++) { + for (n = n_xfers, k_tmp = k_xfers, u_tmp = u_xfers; + n; + n--, k_tmp++, u_tmp++) { if (u_tmp->rx_buf) { if (copy_to_user((u8 __user *) - (uintptr_t) u_tmp->rx_buf, rx_buf, + (uintptr_t) u_tmp->rx_buf, k_tmp->rx_buf, u_tmp->len)) { status = -EFAULT; goto done; } - rx_buf += u_tmp->len; } } status = total;