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=-8.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,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 EC782C5517A for ; Thu, 29 Oct 2020 12:26:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9829420796 for ; Thu, 29 Oct 2020 12:26:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726526AbgJ2M0E (ORCPT ); Thu, 29 Oct 2020 08:26:04 -0400 Received: from mx2.suse.de ([195.135.220.15]:33310 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726439AbgJ2M0B (ORCPT ); Thu, 29 Oct 2020 08:26:01 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 6ED41AD31; Thu, 29 Oct 2020 12:26:00 +0000 (UTC) Received: by ds.suse.cz (Postfix, from userid 10065) id 7BB8ADA7D9; Thu, 29 Oct 2020 13:24:25 +0100 (CET) Date: Thu, 29 Oct 2020 13:24:25 +0100 From: David Sterba To: fdmanana@kernel.org Cc: linux-btrfs@vger.kernel.org Subject: Re: [PATCH] btrfs: do not start and wait for delalloc on snapshot roots on transaction commit Message-ID: <20201029122425.GJ6756@twin.jikos.cz> Reply-To: dsterba@suse.cz Mail-Followup-To: dsterba@suse.cz, fdmanana@kernel.org, linux-btrfs@vger.kernel.org References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23.1-rc1 (2014-03-12) Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org On Tue, Oct 27, 2020 at 12:40:06PM +0000, fdmanana@kernel.org wrote: > From: Filipe Manana > > We do not need anymore to start writeback for delalloc of roots that are > being snapshoted and wait for it to complete. This was done in commit > 609e804d771f59 ("Btrfs: fix file corruption after snapshotting due to mix > of buffered/DIO writes") to fix a type of file corruption where files in a > snapshot end up having their i_size updated in a non-ordered way, leaving > implicit file holes, when buffered IO writes that increase a file's size > are followed by direct IO writes that also increase the file's size. > > This is not needed anymore because we now have a more generic mechanism > to prevent a non-ordered i_size update since commit 9ddc959e802bf7 > ("btrfs: use the file extent tree infrastructure"), which addresses this > scenario involving snapshots as well. > > Signed-off-by: Filipe Manana Added to misc-next, thanks.