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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 483DFC433EF for ; Mon, 14 Mar 2022 09:21:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237915AbiCNJWU (ORCPT ); Mon, 14 Mar 2022 05:22:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59858 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232571AbiCNJWT (ORCPT ); Mon, 14 Mar 2022 05:22:19 -0400 Received: from out28-75.mail.aliyun.com (out28-75.mail.aliyun.com [115.124.28.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CF4EE427F1; Mon, 14 Mar 2022 02:21:08 -0700 (PDT) X-Alimail-AntiSpam: AC=CONTINUE;BC=0.07863903|-1;CH=green;DM=|CONTINUE|false|;DS=CONTINUE|ham_regular_dialog|0.00699087-0.00170898-0.9913;FP=0|0|0|0|0|-1|-1|-1;HT=ay29a033018047199;MF=michael@allwinnertech.com;NM=1;PH=DS;RN=8;RT=8;SR=0;TI=SMTPD_---.N49gzxq_1647249655; Received: from 172.30.10.142(mailfrom:michael@allwinnertech.com fp:SMTPD_---.N49gzxq_1647249655) by smtp.aliyun-inc.com(33.32.109.194); Mon, 14 Mar 2022 17:21:06 +0800 Message-ID: <88e53cb9-791f-ee58-9be8-76ae9986e0e2@allwinnertech.com> Date: Mon, 14 Mar 2022 17:20:55 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.6.2 From: Michael Wu Subject: Re: [PATCH] mmc: block: enable cache-flushing when mmc cache is on To: Adrian Hunter , ulf.hansson@linaro.org, avri.altman@wdc.com, beanhuo@micron.com, porzio@gmail.com Cc: linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org, allwinner-opensource-support References: <20220312044315.7994-1-michael@allwinnertech.com> <83edf9a1-1712-5388-a3fa-d685f1f581df@intel.com> Content-Language: en-GB In-Reply-To: <83edf9a1-1712-5388-a3fa-d685f1f581df@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14/03/2022 14:54, Adrian Hunter wrote: > On 12/03/2022 06:43, Michael Wu wrote: >> The mmc core enable cache on default. But it only enables cache-flushing >> when host supports cmd23 and eMMC supports reliable write. >> For hosts which do not support cmd23 or eMMCs which do not support >> reliable write, the cache can not be flushed by `sync` command. >> This may leads to cache data lost. >> This patch enables cache-flushing as long as cache is enabled, no >> matter host supports cmd23 and/or eMMC supports reliable write or not. >> > > Fixes tag? > Hi Adrian, My patch intend to fix the cache problem brought by the following two patches: Fixes: d0c97cfb81ebc ("mmc: core: Use CMD23 for multiblock transfers when we can.") Fixes: e9d5c746246c8 ("mmc/block: switch to using blk_queue_write_cache()") I'm not sure if this is what you referred to ("Fixes tag"). Please correct me if I misunderstood. >> Signed-off-by: Michael Wu >> --- >> drivers/mmc/core/block.c | 20 ++++++++++++++------ >> 1 file changed, 14 insertions(+), 6 deletions(-) >> >> diff --git a/drivers/mmc/core/block.c b/drivers/mmc/core/block.c >> index 689eb9afeeed..1e508c079c1e 100644 >> --- a/drivers/mmc/core/block.c >> +++ b/drivers/mmc/core/block.c >> @@ -2279,6 +2279,8 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card, >> struct mmc_blk_data *md; >> int devidx, ret; >> char cap_str[10]; >> + bool enable_cache = false; >> + bool enable_fua = false; >> >> devidx = ida_simple_get(&mmc_blk_ida, 0, max_devices, GFP_KERNEL); >> if (devidx < 0) { >> @@ -2375,12 +2377,18 @@ static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card, >> md->flags |= MMC_BLK_CMD23; >> } >> >> - if (mmc_card_mmc(card) && >> - md->flags & MMC_BLK_CMD23 && >> - ((card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN) || >> - card->ext_csd.rel_sectors)) { >> - md->flags |= MMC_BLK_REL_WR; >> - blk_queue_write_cache(md->queue.queue, true, true); >> + if (mmc_card_mmc(card)) { >> + if (md->flags & MMC_BLK_CMD23 && >> + ((card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN) || >> + card->ext_csd.rel_sectors)) { >> + md->flags |= MMC_BLK_REL_WR; >> + enable_fua = true; >> + } >> + >> + if (mmc_cache_enabled(card->host)) >> + enable_cache = true; >> + >> + blk_queue_write_cache(md->queue.queue, enable_cache, enable_fua); >> } > > Seems like we should inform block layer about SD card cache also > I saw another mail by Avri Altman, which says few days will be needed to ask internally. Shall I wait or make another change here on 'inform block layer about SD card cache'? >> >> string_get_size((u64)size, 512, STRING_UNITS_2, -- Best Regards, Michael Wu