From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760505AbYAKJGk (ORCPT ); Fri, 11 Jan 2008 04:06:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755921AbYAKJG0 (ORCPT ); Fri, 11 Jan 2008 04:06:26 -0500 Received: from brick.kernel.dk ([87.55.233.238]:18565 "EHLO kernel.dk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755823AbYAKJGY (ORCPT ); Fri, 11 Jan 2008 04:06:24 -0500 Date: Fri, 11 Jan 2008 10:06:21 +0100 From: Jens Axboe To: Chris Smowton Cc: linux-kernel@vger.kernel.org Subject: Re: Splice(): exports for module programmers Message-ID: <20080111090621.GH6258@kernel.dk> References: <4786D7E5.2080701@cam.ac.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4786D7E5.2080701@cam.ac.uk> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jan 11 2008, Chris Smowton wrote: > Just a couple of quick questions if anyone can shed light regarding > functions exported for modules relating to splice(): > > * Is there a particular reason why the useful helper __splice_from_pipe > is exported, but not the locking equivalent splice_from_pipe or its > equally useful helper splice_to_pipe? > * Similarly is there anything wrong with exporting the generic > pipe-buffer operations (e.g. generic_pipe_buf_map) to save effort > writing modules which implement splice_read and splice_write? > > Are these unexported because they are unstable and not yet considered > suitable for use, or simply because nobody's written a module that > splice()s yet? The latter, I generally don't export things until they are used. __splice_from_pipe() wasn't exported until some file systems grew they own splice implementations. -- Jens Axboe