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 E6304C54EAA for ; Mon, 30 Jan 2023 12:18:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236499AbjA3MS2 (ORCPT ); Mon, 30 Jan 2023 07:18:28 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50426 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236302AbjA3MS1 (ORCPT ); Mon, 30 Jan 2023 07:18:27 -0500 Received: from verein.lst.de (verein.lst.de [213.95.11.211]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 607E2B74D; Mon, 30 Jan 2023 04:18:26 -0800 (PST) Received: by verein.lst.de (Postfix, from userid 2407) id 2E41068B05; Mon, 30 Jan 2023 13:18:21 +0100 (CET) Date: Mon, 30 Jan 2023 13:18:20 +0100 From: Christoph Hellwig To: David Howells Cc: Christoph Hellwig , linux-block@vger.kernel.org, ceph-devel@vger.kernel.org, virtualization@lists.linux-foundation.org, linux-nvme@lists.infradead.org, linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, kvm@vger.kernel.org, netdev@vger.kernel.org, linux-afs@lists.infradead.org, linux-cifs@vger.kernel.org, samba-technical@lists.samba.org, linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, devel@lists.orangefs.org, io-uring@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH 20/23] rxrpc: use bvec_set_page to initialize a bvec Message-ID: <20230130121820.GA18981@lst.de> References: <20230130103343.GA11663@lst.de> <20230130092157.1759539-21-hch@lst.de> <20230130092157.1759539-1-hch@lst.de> <3347459.1675074683@warthog.procyon.org.uk> <3351918.1675077855@warthog.procyon.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3351918.1675077855@warthog.procyon.org.uk> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On Mon, Jan 30, 2023 at 11:24:15AM +0000, David Howells wrote: > Seems to be something people want to do quite a lot and don't know about. Hmm. Right now there is one case where it would be used, and there's about three that are and should be using bio_add_page. > I've seen places where someone allocates a buffer and clears it just to use as > a source of zeros. There's at least one place in cifs, for example. I know > about it from wrangling arch code, but most people working on Linux haven't > done that. But we don't really need a helper for every possible page use for that. People just need to learn about ZERO_PAGE.