From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 337C426ED46; Fri, 26 Jun 2026 05:38:52 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.11.211 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782452334; cv=none; b=b7TIfkn/wT5MzrtoSl9ZvyFf/QIenPem8iZx/Exe/KmzFBzP1XksyP50SQZE7+CB/1sMGF4G8B6yEay4CUMZHw+qEdC8lOyGu8vmT7inl4zqi4wgLBfvYmdq4ZLR5GZuef2bBNeujUkYCMZFSWkZbNs1L0PwkZaWevDXdjKN7lA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782452334; c=relaxed/simple; bh=M3BEVc6kpTYWFuSxhIw16hCOS+d5IcWN0/TUy1yXdmU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rreNllE5bRN8KgNxo4UPsPTMLs5IuAmpd4wilNkL4fK85MjpUPu6cEkzRQnnKBNwBO5+awUYG3RtesaXSckW6mWTV8DqlZIGKp7Q5O22xu1exyY04Ph6NUeGcFxRKTRF6zaJsGmVds9Di02/RAn+k6HzcC4pTXRLsopeIpeFv2k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de; spf=pass smtp.mailfrom=lst.de; arc=none smtp.client-ip=213.95.11.211 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lst.de Received: by verein.lst.de (Postfix, from userid 2407) id 8ED4B68B05; Fri, 26 Jun 2026 07:38:49 +0200 (CEST) Date: Fri, 26 Jun 2026 07:38:49 +0200 From: Christoph Hellwig To: Gao Xiang Cc: Christoph Hellwig , Joanne Koong , willy@infradead.org, djwong@kernel.org, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org Subject: Re: [RFC PATCH v1 0/3] iomap: convert to in-iter ->iomap_next() model Message-ID: <20260626053849.GA9597@lst.de> References: <20260625024723.1611000-1-joannelkoong@gmail.com> <6446cb94-a005-4e4c-8034-d7bf2a4b402b@linux.alibaba.com> <20260625130206.GC22620@lst.de> <4da9a5ac-2a53-4fe2-9283-2e0f6181c248@linux.alibaba.com> <9bfa2c7a-1b17-41c5-9846-340e6a5b4b66@linux.alibaba.com> <20260626051004.GA8968@lst.de> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) On Fri, Jun 26, 2026 at 01:35:33PM +0800, Gao Xiang wrote: > I know it's much better to "show the code" but I also think it's > useful to comment ideas now rather than later in case that anyone > is interested so that it could be useful for their adaption. Sure. > I hope I could arrange it in my formal todo list, but I've already > had a bunch of other things (erofs fsdax dedupe support as I told > to you since it impacts workloads, and some overlayfs improvement > and more) in my scheduling list. > > Although I tend to play with this idea, it's not a blocker on > my main interested use cases for now. Also see if some > complicated conversion like btrfs and f2fs can make more related > developers interested in following this way. Yeah. But for now I'd like to get the relatively low hanging fruit done. And Joanne showed that moving from begin/end to an iter is actually way simpler than I thought by having the iomap_process helper that still does get callbacks, but which get inlined. So I'd be really happy to get this done ASAP before we get a lot more conversions, and also to avoid having a partial transitition where we need to keep the old ops around for too long. After that doing the inlining as in patch 3 becomes pretty easy, so we can do it where it matter like direct I/O. And also once we are down to a single callback I think we have a better baseline for your idea. > > Thanks, > Gao Xiang ---end quoted text---