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=-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 539D0C433E1 for ; Mon, 17 Aug 2020 18:05:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 353CF2072E for ; Mon, 17 Aug 2020 18:05:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597687519; bh=U0bh/7rjqFutRw+6kjcehtrpidxTCu+3tEUNf26pJMc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=eB4n6hmSPF7SRPHM/a64XqfdMvsnZ5MbqjTsc1L3mhKO3ue3tP/4Yf6UJXGmhAY66 ODZ+Qh2Ha4RNTmURX1toXxqSnsqAXou3Oa+GrKlDjFP3hmbcq8gh6fVGDuhf4y5g3+ 005VY0hAPHkFPw4n49e29uiIMbetWw41KN1NBqqg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390235AbgHQSFR (ORCPT ); Mon, 17 Aug 2020 14:05:17 -0400 Received: from mail.kernel.org ([198.145.29.99]:33516 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388515AbgHQQJi (ORCPT ); Mon, 17 Aug 2020 12:09:38 -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 D7EC02245C; Mon, 17 Aug 2020 16:09:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1597680577; bh=U0bh/7rjqFutRw+6kjcehtrpidxTCu+3tEUNf26pJMc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=u8Nas3LzTD4T17W+4W1+ScBy5FxUq4ekJTxlgtRNJgnnsWvzak1HBz/+05LzmRjiL ytWvUlX3NFe079TiAdWNaAiTV3E2JOTA/Iu0U5hfCAqGk1A9HC8JOVh7+8o1JvTCCy ZXDSGQ3BzZ/3C+6253Yj1GDppW1y7iirINTEC/AA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Christian Eggers , Mark Brown Subject: [PATCH 5.4 243/270] spi: spidev: Align buffers for DMA Date: Mon, 17 Aug 2020 17:17:24 +0200 Message-Id: <20200817143807.923171407@linuxfoundation.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20200817143755.807583758@linuxfoundation.org> References: <20200817143755.807583758@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@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 @@ -223,6 +223,11 @@ 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; @@ -238,17 +243,17 @@ 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; @@ -258,7 +263,7 @@ 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; @@ -290,16 +295,16 @@ 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;