From patchwork Fri Sep 9 19:19:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 12972069 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 30585ECAAD5 for ; Fri, 9 Sep 2022 19:19:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230254AbiIITTs (ORCPT ); Fri, 9 Sep 2022 15:19:48 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52878 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230150AbiIITTm (ORCPT ); Fri, 9 Sep 2022 15:19:42 -0400 Received: from mail.baikalelectronics.com (mail.baikalelectronics.com [87.245.175.230]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 75D0D2A42B; Fri, 9 Sep 2022 12:19:40 -0700 (PDT) Received: from mail (mail.baikal.int [192.168.51.25]) by mail.baikalelectronics.com (Postfix) with ESMTP id 3D9A2DBB; Fri, 9 Sep 2022 22:23:11 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.baikalelectronics.com 3D9A2DBB DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baikalelectronics.ru; s=mail; t=1662751391; bh=k04JpT/Stk+B/Zc/3fGfPQL4s7cQC+RHy2d6ex7akDU=; h=From:To:CC:Subject:Date:In-Reply-To:References:From; b=O4gzvBhHAEGnSNm1f2kkZ6UEROqGLedhiAQeKD2i2IPo4oHcWkAVshH5GltVljce7 PudFDDrmSGjqMFYD5fBijw38Upb/+TrRtwNPdD3nUpAlpRee9joZr4YINs3kF+CCCd YSIPFPKpAb7az2+yxffnEs0ilQlNlpMIxlPTfu5g= Received: from localhost (192.168.168.10) by mail (192.168.51.25) with Microsoft SMTP Server (TLS) id 15.0.1395.4; Fri, 9 Sep 2022 22:19:21 +0300 From: Serge Semin To: Jonathan Derrick , Revanth Rajashekar , Jens Axboe , Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , Rafael Antognolli , Scott Bauer CC: Serge Semin , Serge Semin , Alexey Malahov , Pavel Parkhomenko , Thomas Bogendoerfer , , , Subject: [PATCH 2/2] block: sed-opal: Cache-line-align the cmd/resp buffers Date: Fri, 9 Sep 2022 22:19:16 +0300 Message-ID: <20220909191916.16013-3-Sergey.Semin@baikalelectronics.ru> In-Reply-To: <20220909191916.16013-1-Sergey.Semin@baikalelectronics.ru> References: <20220909191916.16013-1-Sergey.Semin@baikalelectronics.ru> MIME-Version: 1.0 X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org In accordance with [1] the DMA-able memory buffers must be cacheline-aligned otherwise the cache writing-back and invalidation performed during the mapping may cause the adjacent data being lost. It's specifically required for the DMA-noncoherent platforms. Seeing the opal_dev.{cmd,resp} buffers are used for DMAs in the NVME and SCSI/SD drivers in framework of the nvme_sec_submit() and sd_sec_submit() methods respectively we must make sure the passed buffers are cacheline-aligned to prevent the denoted problem. [1] Documentation/core-api/dma-api.rst Fixes: 455a7b238cd6 ("block: Add Sed-opal library") Signed-off-by: Serge Semin --- block/sed-opal.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/block/sed-opal.c b/block/sed-opal.c index 9700197000f2..222acbd1f03a 100644 --- a/block/sed-opal.c +++ b/block/sed-opal.c @@ -73,6 +73,7 @@ struct parsed_resp { struct opal_resp_tok toks[MAX_TOKS]; }; +/* Presumably DMA-able buffers must be cache-aligned */ struct opal_dev { bool supported; bool mbr_enabled; @@ -88,8 +89,8 @@ struct opal_dev { u64 lowest_lba; size_t pos; - u8 cmd[IO_BUFFER_LENGTH]; - u8 resp[IO_BUFFER_LENGTH]; + u8 cmd[IO_BUFFER_LENGTH] ____cacheline_aligned; + u8 resp[IO_BUFFER_LENGTH] ____cacheline_aligned; struct parsed_resp parsed; size_t prev_d_len;