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 0D381C77B6F for ; Tue, 11 Apr 2023 05:22:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229988AbjDKFWT (ORCPT ); Tue, 11 Apr 2023 01:22:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229974AbjDKFWR (ORCPT ); Tue, 11 Apr 2023 01:22:17 -0400 Received: from mail-pl1-x62e.google.com (mail-pl1-x62e.google.com [IPv6:2607:f8b0:4864:20::62e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8FB6269E; Mon, 10 Apr 2023 22:22:16 -0700 (PDT) Received: by mail-pl1-x62e.google.com with SMTP id n14so31895592plc.8; Mon, 10 Apr 2023 22:22:16 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; t=1681190536; x=1683782536; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=uGx1WHHG4yxIoqah22dglkintMa8RBxc6irauTziWjw=; b=dqcyZPAimsqjJnqhoUSzDw1jR6VKKfiHPJcTVneeGgAfFOzEQiC3AyncvfpFRq5KNW 7WSZW/0N1i+RjrKKO948b9dZgP+97/TjZalZZ9M6eD/pJpckLc6BNu0UYNl6gzjmubVB M3Ge7vUcxWZ3E3lLZlsC47lfgYSU4LZskUViPu+QMFbN+U9Hexn8jOQP3sNuXeOlbvam 7/vTCBpPjQdQnSGMJlu/3udMGJwn3EBxkkt4YMYlYsX0majZajBa73fd7QDO2z18+TtV j5bhGm/HSFlf75WJ9OoFhktC0WwUk9I/J1u2s/+jbTtmrHa/GcMcCmvWUw2GOdyB+ckv tIyw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1681190536; x=1683782536; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=uGx1WHHG4yxIoqah22dglkintMa8RBxc6irauTziWjw=; b=gwd8hzoRLH+k8Z7A6sh4YNu5IzfU+qltd503jShuR6zqgBvFq8x9c769beKFMiU+0H PC4ACT/Jx3n3256lMXnFp+3sNjxqja4IHjOMJJJ7mPuotmtiRun5vFZsG7V9aZ0lifdA YVV2zFnBYNblHQEt4g1AjD/Y+bhk+AH/bfwP8Cm50oP/dHIK6qGcg+cstrwS2QFEHwlM 8E+CGario2ubYYZRiYhNp/Tvd5jdrx1pYWlN2DIuugnaP7q4ZdmULqH0ukcMRx1IqelB qwp5MOsI3FFAgGUSK8zs0PHJSJC5KPfmv1TuibcZas/3ev8pmEpqNeeg8+BhJppodXLH UcXQ== X-Gm-Message-State: AAQBX9dCAE9xlueiAkrwlE5Ar2WGtyrd3OUb8ykVxGi9Pv3ufosu5aQO ygjbxjuH/+ZralMFadKoytrsFZI+gV4= X-Google-Smtp-Source: AKy350bLyBje4Yn44rTqdahx13I4lTgh3dsSWuRTr/wCvqCgPI6NyaDSA5EC3X8tSudQJTFZnlv+zw== X-Received: by 2002:a17:90b:4a4e:b0:246:b635:b7fc with SMTP id lb14-20020a17090b4a4e00b00246b635b7fcmr5703080pjb.5.1681190536064; Mon, 10 Apr 2023 22:22:16 -0700 (PDT) Received: from rh-tp.ibmuc.com ([2406:7400:63:7035:9095:349e:5f0b:ded0]) by smtp.gmail.com with ESMTPSA id v19-20020a17090abb9300b00246d7cd7327sm646154pjr.51.2023.04.10.22.22.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 10 Apr 2023 22:22:15 -0700 (PDT) From: "Ritesh Harjani (IBM)" To: linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org Cc: Jan Kara , Christoph Hellwig , "Darrick J . Wong" , Ojaswin Mujoo , "Ritesh Harjani (IBM)" Subject: [RFCv2 2/8] libfs: Add __generic_file_fsync_nolock implementation Date: Tue, 11 Apr 2023 10:51:50 +0530 Message-Id: <6fad2ec25bccbbb9b3effbd18c2d6d6965b9a33c.1681188927.git.ritesh.list@gmail.com> X-Mailer: git-send-email 2.39.2 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Some of the higher layers like iomap takes inode_lock() when calling generic_write_sync(). Also writeback already happens from other paths without inode lock, so it's difficult to say that we really need sync_mapping_buffers() to take any inode locking here. Having said that, let's add a _nolock variant of this function in libfs for now so that filesystems like ext2 and ext4's nojournal mode can use it. Ext4 when got converted to iomap for direct-io already copied it's own variant of __generic_file_fsync() without lock. Hence let's add a helper API and use it both in ext2 and ext4. Later we can review other filesystems as well to see if we can make _nolock as the default path if inode_lock() is not necessary here. Signed-off-by: Ritesh Harjani (IBM) --- fs/libfs.c | 43 +++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 1 + 2 files changed, 44 insertions(+) diff --git a/fs/libfs.c b/fs/libfs.c index 4eda519c3002..d2dfb72e3cf8 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -1110,6 +1110,49 @@ struct dentry *generic_fh_to_parent(struct super_block *sb, struct fid *fid, } EXPORT_SYMBOL_GPL(generic_fh_to_parent); +/** + * __generic_file_fsync_nolock - generic fsync implementation for simple + * filesystems with no inode lock + * + * @file: file to synchronize + * @start: start offset in bytes + * @end: end offset in bytes (inclusive) + * @datasync: only synchronize essential metadata if true + * + * This is a generic implementation of the fsync method for simple + * filesystems which track all non-inode metadata in the buffers list + * hanging off the address_space structure. + */ +int __generic_file_fsync_nolock(struct file *file, loff_t start, loff_t end, + int datasync) +{ + struct inode *inode = file->f_mapping->host; + int err; + int ret; + + err = file_write_and_wait_range(file, start, end); + if (err) + return err; + + ret = sync_mapping_buffers(inode->i_mapping); + if (!(inode->i_state & I_DIRTY_ALL)) + goto out; + if (datasync && !(inode->i_state & I_DIRTY_DATASYNC)) + goto out; + + err = sync_inode_metadata(inode, 1); + if (ret == 0) + ret = err; + +out: + /* check and advance again to catch errors after syncing out buffers */ + err = file_check_and_advance_wb_err(file); + if (ret == 0) + ret = err; + return ret; +} +EXPORT_SYMBOL(__generic_file_fsync_nolock); + /** * __generic_file_fsync - generic fsync implementation for simple filesystems * diff --git a/include/linux/fs.h b/include/linux/fs.h index c85916e9f7db..21d2b5670308 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2935,6 +2935,7 @@ extern ssize_t simple_read_from_buffer(void __user *to, size_t count, extern ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos, const void __user *from, size_t count); +extern int __generic_file_fsync_nolock(struct file *, loff_t, loff_t, int); extern int __generic_file_fsync(struct file *, loff_t, loff_t, int); extern int generic_file_fsync(struct file *, loff_t, loff_t, int); -- 2.39.2