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=-3.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 CEFDDC433E5 for ; Fri, 10 Jul 2020 13:11:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9EE2B2077D for ; Fri, 10 Jul 2020 13:11:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="guOL/xNZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727864AbgGJNLI (ORCPT ); Fri, 10 Jul 2020 09:11:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59916 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727828AbgGJNLG (ORCPT ); Fri, 10 Jul 2020 09:11:06 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 379D4C08C5DC; Fri, 10 Jul 2020 06:11:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Cbpe7zSMdSUcQMT3p8w0i4/fAKowGRHHeGZ5ArJiJPA=; b=guOL/xNZYChy5mK9TQkICadN1w G0xB8bU5w3TVfNTItcn2mdcu47Pg2WeF1uslEx8kYC4w0HdOVjuEJ/C76Va6eeTdyLZw1uAZZX7rp ZrY8oPeIbpf3nZzqzPk4pYoem+9nTFcTyRu/vq/8M2vHE0L68qTGWBdVYn61ixUhaTMhnMk7K4mWq X+BzUXvtWCVyrHIV+6qaqfcRkWKMp1JGJL/l1l96rGBeoGDp0CtbCo1eY5tZfQEntDMaIRDTNfnm2 +JSJAEvKhnLErSiNGy3D2P7x0dZQujCoGEhL12ieHVjv0qgS/ZRDJ+Dvu6Azvb7bgnFNyrNwsL3uA eAO+Q3ZQ==; Received: from hch by casper.infradead.org with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jtsnm-0002DE-8H; Fri, 10 Jul 2020 13:10:54 +0000 Date: Fri, 10 Jul 2020 14:10:54 +0100 From: Christoph Hellwig To: Kanchan Joshi Cc: Jens Axboe , Christoph Hellwig , Kanchan Joshi , viro@zeniv.linux.org.uk, bcrl@kvack.org, Damien.LeMoal@wdc.com, asml.silence@gmail.com, linux-fsdevel@vger.kernel.org, Matias Bj??rling , linux-kernel@vger.kernel.org, linux-aio@kvack.org, io-uring@vger.kernel.org, linux-block@vger.kernel.org, Selvakumar S , Nitesh Shetty , Javier Gonzalez Subject: Re: [PATCH v3 4/4] io_uring: add support for zone-append Message-ID: <20200710131054.GB7491@infradead.org> References: <1593974870-18919-5-git-send-email-joshi.k@samsung.com> <20200709085501.GA64935@infradead.org> <20200709140053.GA7528@infradead.org> <2270907f-670c-5182-f4ec-9756dc645376@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org. See http://www.infradead.org/rpr.html Sender: io-uring-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Fri, Jul 10, 2020 at 12:35:43AM +0530, Kanchan Joshi wrote: > Append required special treatment (conversion for sector to bytes) for io_uring. > And we were planning a user-space wrapper to abstract that. > > But good part (as it seems now) was: append result went along with cflags at > virtually no additional cost. And uring code changes became super clean/minimal > with further revisions. > While indirect-offset requires doing allocation/mgmt in application, > io-uring submission > and in completion path (which seems trickier), and those CQE flags > still get written > user-space and serve no purpose for append-write. I have to say that storing the results in the CQE generally make so much more sense. I wonder if we need a per-fd "large CGE" flag that adds two extra u64s to the CQE, and some ops just require this version.