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 A6B6FEB64DC for ; Fri, 21 Jul 2023 11:27:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229836AbjGUL1j (ORCPT ); Fri, 21 Jul 2023 07:27:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38744 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229681AbjGUL1i (ORCPT ); Fri, 21 Jul 2023 07:27:38 -0400 Received: from out-50.mta1.migadu.com (out-50.mta1.migadu.com [95.215.58.50]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BD661198D for ; Fri, 21 Jul 2023 04:27:36 -0700 (PDT) Message-ID: <2622afd7-228f-02f3-3b72-a1c826844126@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1689938855; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=O1t9Noi98+yFXc3CQ7auVWOS7sGiO5j4YJVgm2UWIUI=; b=ZGXGQqmO6C2vVev3Ly+V0Mg0alKF5MCdliO6ovbAsCXUCYvlLt79Zy6TtMnonP+KVL7dl9 jSQN+GBcm0eI2eVXdNSDM2fPs7tKd/W5iatU3+3OfsWaQnohX1dG16VXhyV1TnRFHqU1nG k4jub15DMgEV1AqUn7hXu4gQiA7Z/7E= Date: Fri, 21 Jul 2023 19:27:26 +0800 MIME-Version: 1.0 Subject: Re: [External] [fuse-devel] [PATCH 3/3] fuse: write back dirty pages before direct write in direct_io_relax mode Content-Language: en-US To: Jiachen Zhang , fuse-devel@lists.sourceforge.net Cc: linux-fsdevel@vger.kernel.org, bernd.schubert@fastmail.fm, Wanpeng Li , cgxu519@mykernel.net, miklos@szeredi.hu References: <20230630094602.230573-1-hao.xu@linux.dev> <20230630094602.230573-4-hao.xu@linux.dev> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Hao Xu In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On 7/21/23 14:35, Jiachen Zhang wrote: > > On 2023/6/30 17:46, Hao Xu wrote: >> From: Hao Xu >> >> In direct_io_relax mode, there can be shared mmaped files and thus dirty >> pages in its page cache. Therefore those dirty pages should be written >> back to backend before direct write to avoid data loss. >> >> Signed-off-by: Hao Xu >> --- >>   fs/fuse/file.c | 7 +++++++ >>   1 file changed, 7 insertions(+) >> >> diff --git a/fs/fuse/file.c b/fs/fuse/file.c >> index 176f719f8fc8..7c9167c62bf6 100644 >> --- a/fs/fuse/file.c >> +++ b/fs/fuse/file.c >> @@ -1485,6 +1485,13 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, >> struct iov_iter *iter, >>       if (!ia) >>           return -ENOMEM; >> +    if (fopen_direct_write && fc->direct_io_relax) { >> +        res = filemap_write_and_wait_range(mapping, pos, pos + count >> - 1); >> +        if (res) { >> +            fuse_io_free(ia); >> +            return res; >> +        } >> +    } >>       if (!cuse && fuse_range_is_writeback(inode, idx_from, idx_to)) { >>           if (!write) >>               inode_lock(inode); > > Tested-by: Jiachen Zhang > > > Looks good to me. > > By the way, the behaviour would be a first FUSE_WRITE flushing the page > cache, followed by a second FUSE_WRITE doing the direct IO. In the > future, further optimization could be first write into the page cache > and then flush the dirty page to the FUSE daemon. > I think this makes sense, cannot think of any issue in it for now, so I'll do that change and send next version, super thanks, Jiachen! Thanks, Hao > > Thanks, > Jiachen