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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5A29C64ED6 for ; Mon, 27 Feb 2023 20:25:01 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 369F66B0073; Mon, 27 Feb 2023 15:25:00 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 2F4196B0075; Mon, 27 Feb 2023 15:25:00 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 193D76B0078; Mon, 27 Feb 2023 15:25:00 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 073076B0073 for ; Mon, 27 Feb 2023 15:25:00 -0500 (EST) Received: from smtpin07.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id C6F241406BE for ; Mon, 27 Feb 2023 20:24:59 +0000 (UTC) X-FDA: 80514200718.07.BC7A29C Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf23.hostedemail.com (Postfix) with ESMTP id 7CE8D140003 for ; Mon, 27 Feb 2023 20:24:57 +0000 (UTC) Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b="pF/JXdmL"; dmarc=fail reason="No valid SPF, DKIM not aligned (relaxed)" header.from=kernel.org (policy=none); spf=none (imf23.hostedemail.com: domain of mcgrof@infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=mcgrof@infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1677529498; h=from:from:sender:sender: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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=Jsu++lcHYzuet/KiQ3YlPNZNjeeuY0q0dMt84g4AOO4=; b=Nm4XdhQL5fOU4Mi4hPkATw3sRcHGYR3icCHy6esIqDnLOLn7eslzPeJ1dsBZTvw6iYIc2o UrFgXDyyPtUgG74TW8w7vTKVW/zVbZ2/QJSqD0AKOWaIg8dP3ekXbR1j5jasAdUVTPv+Oi l7BaPdhCo93LPZrHcJ25rupiVOpymNs= ARC-Authentication-Results: i=1; imf23.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b="pF/JXdmL"; dmarc=fail reason="No valid SPF, DKIM not aligned (relaxed)" header.from=kernel.org (policy=none); spf=none (imf23.hostedemail.com: domain of mcgrof@infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=mcgrof@infradead.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1677529498; a=rsa-sha256; cv=none; b=fUYe9abXMRSlKqRsaHRp/rE9CBrZoFkQr5OSM/Uag2tXT+l0FYFAR2B72zebSlgwH9Pl0d PyEzZT40YFK5JEouunBgwMrtTBMVF7116ykPd1dK3usiJti7Sp9LRmFTQoA55K2FQ38PMV 2rKuNDJ99JbGYbPKY5N0tfdwS2MeRFk= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Jsu++lcHYzuet/KiQ3YlPNZNjeeuY0q0dMt84g4AOO4=; b=pF/JXdmLH+qUkvD7NBgSSAXU48 ouw1p3TSniwljGe7vrzt0qcN1vzSumtdLK+U418cBgNZW6eC0h2WcKJuN2qXOzNCE1PlyyMyJKvss Ai219Ccgx1/Xj8dXRsKSwk0vipETwwYIzf5hgrfopqqt/GTxIb9sG/dXV8TyswnLCH9RWNc2XmqgI 564FBdWxiTjuH8+kTiIRoIX2xVIMjOpqtSZjTHRvCTwdFUJSs7hp6IvBGp9oOahSpXwTrK8wMhBky fCf3caB0aeF0vC1klHy+lkEhEKB+dC6XKDmrvRivtJ6IekFbyiyGgI24i7exoqtO4v7mbJtR+T/vX H9sok0og==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1pWk3H-00B9g1-Ps; Mon, 27 Feb 2023 20:24:51 +0000 Date: Mon, 27 Feb 2023 12:24:51 -0800 From: Luis Chamberlain To: "Darrick J. Wong" Cc: Matthew Wilcox , lsf-pc@lists.linux-foundation.org, Christoph Hellwig , David Howells , "kbus >> Keith Busch" , Pankaj Raghav , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: LSF/MM/BPF 2023 IOMAP conversion status update Message-ID: References: <20230129044645.3cb2ayyxwxvxzhah@garbanzo> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Rspamd-Queue-Id: 7CE8D140003 X-Rspamd-Server: rspam09 X-Rspam-User: X-Stat-Signature: jnhyr575y3xpc8cd8e65gyicruds7pwu X-HE-Tag: 1677529497-599410 X-HE-Meta: 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 pRg08liN 4BTtsK0Sa7MmSpY++1Vs+ubq1znWmCniOacu3Mro5P55nUGPmPPx3BFYmhIhX77TN2OUW3kd7B8PP/5NjN+q0qe4g89IXLsgi+to+MpVl19wmIU6gxK/yY+oQNY2Ruqz8nN1QQCZjQGLLrLQ+ZnGLSibM7SSjfjDPig+n6hlZGKg4ZHd2qsM4RwVgvi5EDR+7Id+7RfM5mU18v9a2o5vp4AXUv10+YMbPojlYZyIHw4UUal0ZTfOMkah+tuC//bABo9IFgj4QEXfB71yPtprTRxXrxBm8WY+isqyBTcirN1zGdvr4c4KuX5oQ/VnKS7/5bPEz X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Feb 27, 2023 at 11:47:24AM -0800, Darrick J. Wong wrote: > OTOH, it also means that we've learned the hard way that pagecache > operations need a means to revalidate mappings to avoid write races. > This applies both to the initial pagecache write and to scheduling > writeback, but the mechanisms for each were developed separately and > years apart. See iomap::validity_cookie and > xfs_writepage_ctx::{data,cow}_seq for what I'm talking about. > We (xfs developers) ought to figure out if these two mechanisms should > be merged before more filesystems start using iomap for buffered io. That puts a good yield notice to some conversion efforts, thanks, this already alone is very useulf. > I'd like to have a discussion about how to clean up and clarify the > iomap interfaces, and a separate one about how to port the remaining 35+ > filesystems. I don't know how exactly to split this into LSF sessions, > other than to suggest at least two. >From a conversion perspective, ideally if it was obvious I think we should be able to do some of it ala coccinelle, but I have yet to see any remotely obvious pattern. And it makes me wonder, should we strive to make the conversion as painless / obvious ? Is that a good litmus for when we should be ready to start converting other filesystems? > If hch or dchinner show up, I also want to drag them into this. :) And here I've been thinking I had to go to Australia to see you all together. Luis