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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no 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 A5793C388F7 for ; Thu, 22 Oct 2020 13:06:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 47F9A24178 for ; Thu, 22 Oct 2020 13:06:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2894464AbgJVNGX (ORCPT ); Thu, 22 Oct 2020 09:06:23 -0400 Received: from mx2.suse.de ([195.135.220.15]:43022 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2507469AbgJVNGX (ORCPT ); Thu, 22 Oct 2020 09:06:23 -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 0270FAC3F; Thu, 22 Oct 2020 13:06:22 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id B4A501E1342; Thu, 22 Oct 2020 15:06:16 +0200 (CEST) Date: Thu, 22 Oct 2020 15:06:16 +0200 From: Jan Kara To: harshad shirwadkar Cc: Jan Kara , Ext4 Developers List , "Theodore Y. Ts'o" Subject: Re: [PATCH v10 1/9] doc: update ext4 and journalling docs to include fast commit feature Message-ID: <20201022130616.GC24163@quack2.suse.cz> References: <20201015203802.3597742-1-harshadshirwadkar@gmail.com> <20201015203802.3597742-2-harshadshirwadkar@gmail.com> <20201021160423.GB25702@quack2.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org On Wed 21-10-20 10:25:14, harshad shirwadkar wrote: > > BTW, how is EXT4_FC_TAG_CREAT different from EXT4_FC_TAG_LINK? It seems > > like they describe essentially the same operation? > In the replay path, creat has to do certain things that link doesn't. > For example, "creat" needs to mark the inode as used in the bitmap and > also if it's a directory that's being created, it needs to initialize > the "." and ".." dirents in the directory. That's why we need > different tags. Aha, OK, makes sence. Thanks for explanation. BTW it would be good to have some documentation (or at least examples) how a sequence of system calls translates to fastcommit log entries and then how these are replayed in case of crash. Honza -- Jan Kara SUSE Labs, CR