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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6828AC77B7C for ; Fri, 5 May 2023 05:29:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229620AbjEEF32 (ORCPT ); Fri, 5 May 2023 01:29:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58504 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229601AbjEEF30 (ORCPT ); Fri, 5 May 2023 01:29:26 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C1B3CA5C8; Thu, 4 May 2023 22:29:25 -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=LQA4GbnUf0oYoIkNnpkgzYq4G7BremfMrzKcIO5uhSU=; b=WTkLoGwYgeTEav6wxaGuDNJQE+ eFWyclwUrUJtrmHDy3DKLjTSKlh2OJWFXvwrDa1/e5Ex8y+NVlnGpktMz5H9E6cPSrAa85ADuPtHs Lqxenv+UZG3U2crlGQ2gSmV4VACixDb0luXKoQXG4JT+KopxH4WZ5WlO772CWplY28bBKM9TU/i4j F3oiu8ddOtvd48FJfWd4JeMSo/dhTpjCSGTIWJviNbFleqvHBLqKdJrIM650Ag/Nm3GYARpr7Ytu4 X/DmBMNHko1g7Aq5CLalf3IapC42jOdmNlonr1eh8p1VTpo6DKRA00M7NcEHcN0ph+KyewE2HuflE 96cFoorQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1puo0N-00BFr5-9p; Fri, 05 May 2023 05:29:19 +0000 Date: Fri, 5 May 2023 06:29:19 +0100 From: Matthew Wilcox To: Andreas Hindborg Cc: Jens Axboe , Christoph Hellwig , Keith Busch , Damien Le Moal , Hannes Reinecke , lsf-pc@lists.linux-foundation.org, rust-for-linux@vger.kernel.org, linux-block@vger.kernel.org, Miguel Ojeda , Alex Gaynor , Wedson Almeida Filho , Boqun Feng , Gary Guo , =?iso-8859-1?Q?Bj=F6rn?= Roy Baron , Benno Lossin , open list , gost.dev@samsung.com Subject: Re: [RFC PATCH 02/11] rust: add `pages` module for handling page allocation Message-ID: References: <20230503090708.2524310-1-nmi@metaspace.dk> <20230503090708.2524310-3-nmi@metaspace.dk> <871qjvtmb5.fsf@metaspace.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <871qjvtmb5.fsf@metaspace.dk> Precedence: bulk List-ID: X-Mailing-List: rust-for-linux@vger.kernel.org On Fri, May 05, 2023 at 06:42:02AM +0200, Andreas Hindborg wrote: > > Matthew Wilcox writes: > > > On Wed, May 03, 2023 at 11:06:59AM +0200, Andreas Hindborg wrote: > >> From: Andreas Hindborg > >> > >> This patch adds support for working with pages of order 0. Support for pages > >> with higher order is deferred. Page allocation flags are fixed in this patch. > >> Future work might allow the user to specify allocation flags. > >> > >> This patch is a heavily modified version of code available in the rust tree [1], > >> primarily adding support for multiple page mapping strategies. > > > > This also seems misaligned with the direction of Linux development. > > Folios are the future, pages are legacy. Please, ask about what's > > going on before wasting time on the past. > > I see, thanks for the heads up! In this case I wanted to do an > apples-apples comparison to the C null_blk driver. Since that is using > kmap I wanted to have that. But let's bind to the folio_* APIs in the > future, that would make sense. Well, kmap() is essentially a no-op on 64-bit systems, so it's not terribly relevant to doing a comparison.