From patchwork Wed Aug 31 07:20:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhang Yi X-Patchwork-Id: 12960439 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 2CE40ECAAD3 for ; Wed, 31 Aug 2022 07:10:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230440AbiHaHKJ (ORCPT ); Wed, 31 Aug 2022 03:10:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50698 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229867AbiHaHKG (ORCPT ); Wed, 31 Aug 2022 03:10:06 -0400 Received: from szxga02-in.huawei.com (szxga02-in.huawei.com [45.249.212.188]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DC732E03D; Wed, 31 Aug 2022 00:10:03 -0700 (PDT) Received: from canpemm500005.china.huawei.com (unknown [172.30.72.53]) by szxga02-in.huawei.com (SkyGuard) with ESMTP id 4MHZvP637NzYcy3; Wed, 31 Aug 2022 15:05:37 +0800 (CST) Received: from huawei.com (10.175.127.227) by canpemm500005.china.huawei.com (7.192.104.229) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 31 Aug 2022 15:10:00 +0800 From: Zhang Yi To: , , , , , , CC: , , , , , , , , , , , , , Subject: [PATCH 00/14] buffer: remove ll_rw_block() Date: Wed, 31 Aug 2022 15:20:57 +0800 Message-ID: <20220831072111.3569680-1-yi.zhang@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To canpemm500005.china.huawei.com (7.192.104.229) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org ll_rw_block() will skip locked buffer before submitting IO, it assumes that locked buffer means it is under IO. This assumption is not always true because we cannot guarantee every buffer lock path would submit IO. After commit 88dbcbb3a484 ("blkdev: avoid migration stalls for blkdev pages"), buffer_migrate_folio_norefs() becomes one exceptional case, and there may be others. So ll_rw_block() is not safe on the sync read path, we could get false positive EIO return value when filesystem reading metadata. It seems that it could be only used on the readahead path. Unfortunately, many filesystem misuse the ll_rw_block() on the sync read path. This patch set just remove ll_rw_block() and add new friendly helpers, which could prevent false positive EIO on the read metadata path. Thanks for the suggestion from Jan, the original discussion is at [1]. patch 1: remove unused helpers in fs/buffer.c patch 2: add new bh_read_[*] helpers patch 3-11: remove all ll_rw_block() calls in filesystems patch 12-14: do some leftover cleanups. Thanks, Yi. [1]. https://lore.kernel.org/linux-mm/20220825080146.2021641-1-chengzhihao1@huawei.com/ Zhang Yi (14): fs/buffer: remove __breadahead_gfp() fs/buffer: add some new buffer read helpers fs/buffer: replace ll_rw_block() gfs2: replace ll_rw_block() isofs: replace ll_rw_block() jbd2: replace ll_rw_block() ntfs3: replace ll_rw_block() ocfs2: replace ll_rw_block() reiserfs: replace ll_rw_block() udf: replace ll_rw_block() ufs: replace ll_rw_block() fs/buffer: remove ll_rw_block() helper ext2: replace bh_submit_read() helper with bh_read_locked() fs/buffer: remove bh_submit_read() helper fs/buffer.c | 150 +++++++++++++++--------------------- fs/ext2/balloc.c | 2 +- fs/gfs2/meta_io.c | 6 +- fs/gfs2/quota.c | 4 +- fs/isofs/compress.c | 2 +- fs/jbd2/journal.c | 7 +- fs/jbd2/recovery.c | 16 ++-- fs/ntfs3/inode.c | 7 +- fs/ocfs2/aops.c | 2 +- fs/ocfs2/super.c | 5 +- fs/reiserfs/journal.c | 11 +-- fs/reiserfs/stree.c | 4 +- fs/reiserfs/super.c | 4 +- fs/udf/dir.c | 2 +- fs/udf/directory.c | 2 +- fs/udf/inode.c | 5 +- fs/ufs/balloc.c | 4 +- include/linux/buffer_head.h | 47 ++++++++--- 18 files changed, 135 insertions(+), 145 deletions(-)