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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT 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 E2A62C3276E for ; Thu, 2 Jan 2020 22:12:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B7C3322314 for ; Thu, 2 Jan 2020 22:12:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578003163; bh=fqZruyXarBHH1x9rF6kKDbJK5w2LbZ8EyRy8jEHQrps=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DZRlI6/+PEiXYPRG00s4GxoPnof/d5OrcBb9RPhAnpy8W+LHuYWR4bLR27oi2NExm 3q6uN73YunISHWUFcKbqXXnQtwvKmq/ld5Ao2X+UaiC8R1nI03+amlsse0HAJgSDD9 P683bHygB9TBi1dZMoAVcfNjKG5kOQZAuZn/7hL0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727522AbgABWMj (ORCPT ); Thu, 2 Jan 2020 17:12:39 -0500 Received: from mail.kernel.org ([198.145.29.99]:51848 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727506AbgABWMg (ORCPT ); Thu, 2 Jan 2020 17:12:36 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (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 4CBB222314; Thu, 2 Jan 2020 22:12:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578003155; bh=fqZruyXarBHH1x9rF6kKDbJK5w2LbZ8EyRy8jEHQrps=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uFxL10Wq+OOOk9O8F9cjyqEph84+T+Ym9JGC4WX2Y4KXoBT0o8Eev/3iioVsur7yM hszhPzprnW4AIwJEyVHfm1/0VQdj6ql3fcpFKXfAfJv6egWIFyUYN/sQHXHSLOEPWs 7VqUnYJ51SGj9S1tIFjQEt0UkVBbolnMJ4FbrFB4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Matthew Bobrowski , Jan Kara , Ritesh Harjani , Theodore Tso , Sasha Levin Subject: [PATCH 5.4 043/191] ext4: iomap that extends beyond EOF should be marked dirty Date: Thu, 2 Jan 2020 23:05:25 +0100 Message-Id: <20200102215834.545756785@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200102215829.911231638@linuxfoundation.org> References: <20200102215829.911231638@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Matthew Bobrowski [ Upstream commit 2e9b51d78229d5145725a481bb5464ebc0a3f9b2 ] This patch addresses what Dave Chinner had discovered and fixed within commit: 7684e2c4384d. This changes does not have any user visible impact for ext4 as none of the current users of ext4_iomap_begin() that extend files depend on IOMAP_F_DIRTY. When doing a direct IO that spans the current EOF, and there are written blocks beyond EOF that extend beyond the current write, the only metadata update that needs to be done is a file size extension. However, we don't mark such iomaps as IOMAP_F_DIRTY to indicate that there is IO completion metadata updates required, and hence we may fail to correctly sync file size extensions made in IO completion when O_DSYNC writes are being used and the hardware supports FUA. Hence when setting IOMAP_F_DIRTY, we need to also take into account whether the iomap spans the current EOF. If it does, then we need to mark it dirty so that IO completion will call generic_write_sync() to flush the inode size update to stable storage correctly. Signed-off-by: Matthew Bobrowski Reviewed-by: Jan Kara Reviewed-by: Ritesh Harjani Link: https://lore.kernel.org/r/8b43ee9ee94bee5328da56ba0909b7d2229ef150.1572949325.git.mbobrowski@mbobrowski.org Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/ext4/inode.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index b10aa115eade..8bba6cd5e870 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3532,8 +3532,14 @@ retry: return ret; } + /* + * Writes that span EOF might trigger an I/O size update on completion, + * so consider them to be dirty for the purposes of O_DSYNC, even if + * there is no other metadata changes being made or are pending here. + */ iomap->flags = 0; - if (ext4_inode_datasync_dirty(inode)) + if (ext4_inode_datasync_dirty(inode) || + offset + length > i_size_read(inode)) iomap->flags |= IOMAP_F_DIRTY; iomap->bdev = inode->i_sb->s_bdev; iomap->dax_dev = sbi->s_daxdev; -- 2.20.1