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=-8.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 F16F5C432C3 for ; Tue, 26 Nov 2019 23:44:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C299820722 for ; Tue, 26 Nov 2019 23:44:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574811871; bh=8xObk1JKbn0x2uZoqD8XspYaUE5uHmLiYAZWiWl2MKw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=tefHn4NbKnm1djNx9FuRv6sDTRx5XE24bq5P1F3fiTyE4kB4XgnFUH054GNK8pdw8 zav62KWQ7ih2zFc1onKcJ7iZLJzGfhzVfHWt/uq43CRvCsap+q0VJZDeD8rhgJTOX7 lx/iHbCPlCWF7TrueicEJQKOnKc+PEyJq7jmKh3Q= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727050AbfKZXoa (ORCPT ); Tue, 26 Nov 2019 18:44:30 -0500 Received: from mail.kernel.org ([198.145.29.99]:47900 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726380AbfKZXoa (ORCPT ); Tue, 26 Nov 2019 18:44:30 -0500 Received: from localhost (unknown [104.132.0.81]) (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 9EE86206CC; Tue, 26 Nov 2019 23:44:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574811869; bh=8xObk1JKbn0x2uZoqD8XspYaUE5uHmLiYAZWiWl2MKw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nTjei7PsgJjFFf3C8lRoDuexiqvwf+EJKVyb6Od9Mce5lglMIR9i61jU1l385RVQI QFhxNOSi9poeYC+U6AA4Ps0vMJ+aYa4Xc1uIs5cUgZJHV8JXEKHsP5zKN5gR2nUzZV TEE9NRhNJxCbhAqDbKV/VzTOq/4finL657urgNcU= Date: Tue, 26 Nov 2019 15:44:28 -0800 From: Jaegeuk Kim To: Damien Le Moal Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Chao Yu , linux-fsdevel@vger.kernel.org, Javier Gonzalez , Shinichiro Kawasaki Subject: Re: [PATCH] f2fs: Fix direct IO handling Message-ID: <20191126234428.GB20652@jaegeuk-macbookpro.roam.corp.google.com> References: <20191126075719.1046485-1-damien.lemoal@wdc.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191126075719.1046485-1-damien.lemoal@wdc.com> User-Agent: Mutt/1.8.2 (2017-04-18) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/26, Damien Le Moal wrote: > f2fs_preallocate_blocks() identifies direct IOs using the IOCB_DIRECT > flag for a kiocb structure. However, the file system direct IO handler > function f2fs_direct_IO() may have decided that a direct IO has to be > exececuted as a buffered IO using the function f2fs_force_buffered_io(). > This is the case for instance for volumes including zoned block device > and for unaligned write IOs with LFS mode enabled. > > These 2 different methods of identifying direct IOs can result in > inconsistencies generating stale data access for direct reads after a > direct IO write that is treated as a buffered write. Fix this > inconsistency by combining the IOCB_DIRECT flag test with the result > of f2fs_force_buffered_io(). > > Reported-by: Javier Gonzalez > Signed-off-by: Damien Le Moal > --- > fs/f2fs/data.c | 4 +++- > 1 file changed, 3 insertions(+), 1 deletion(-) > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > index 5755e897a5f0..8ac2d3b70022 100644 > --- a/fs/f2fs/data.c > +++ b/fs/f2fs/data.c > @@ -1073,6 +1073,8 @@ int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from) > int flag; > int err = 0; > bool direct_io = iocb->ki_flags & IOCB_DIRECT; > + bool do_direct_io = direct_io && > + !f2fs_force_buffered_io(inode, iocb, from); > > /* convert inline data for Direct I/O*/ > if (direct_io) { > @@ -1081,7 +1083,7 @@ int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from) > return err; > } > > - if (direct_io && allow_outplace_dio(inode, iocb, from)) > + if (do_direct_io && allow_outplace_dio(inode, iocb, from)) It seems f2fs_force_buffered_io() includes allow_outplace_dio(). How about this? --- fs/f2fs/data.c | 13 ------------- fs/f2fs/file.c | 35 +++++++++++++++++++++++++---------- 2 files changed, 25 insertions(+), 23 deletions(-) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index a034cd0ce021..fc40a72f7827 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1180,19 +1180,6 @@ int f2fs_preallocate_blocks(struct kiocb *iocb, struct iov_iter *from) int err = 0; bool direct_io = iocb->ki_flags & IOCB_DIRECT; - /* convert inline data for Direct I/O*/ - if (direct_io) { - err = f2fs_convert_inline_inode(inode); - if (err) - return err; - } - - if (direct_io && allow_outplace_dio(inode, iocb, from)) - return 0; - - if (is_inode_flag_set(inode, FI_NO_PREALLOC)) - return 0; - map.m_lblk = F2FS_BLK_ALIGN(iocb->ki_pos); map.m_len = F2FS_BYTES_TO_BLK(iocb->ki_pos + iov_iter_count(from)); if (map.m_len > map.m_lblk) diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index c0560d62dbee..6b32ac6c3382 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -3386,18 +3386,33 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from) ret = -EAGAIN; goto out; } - } else { - preallocated = true; - target_size = iocb->ki_pos + iov_iter_count(from); + goto write; + } - err = f2fs_preallocate_blocks(iocb, from); - if (err) { - clear_inode_flag(inode, FI_NO_PREALLOC); - inode_unlock(inode); - ret = err; - goto out; - } + if (is_inode_flag_set(inode, FI_NO_PREALLOC)) + goto write; + + if (iocb->ki_flags & IOCB_DIRECT) { + /* convert inline data for Direct I/O*/ + err = f2fs_convert_inline_inode(inode); + if (err) + goto out_err; + + if (!f2fs_force_buffered_io(inode, iocb, from)) + goto write; + } + preallocated = true; + target_size = iocb->ki_pos + iov_iter_count(from); + + err = f2fs_preallocate_blocks(iocb, from); + if (err) { +out_err: + clear_inode_flag(inode, FI_NO_PREALLOC); + inode_unlock(inode); + ret = err; + goto out; } +write: ret = __generic_file_write_iter(iocb, from); clear_inode_flag(inode, FI_NO_PREALLOC); -- 2.19.0.605.g01d371f741-goog