From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756821Ab3BVJxb (ORCPT ); Fri, 22 Feb 2013 04:53:31 -0500 Received: from mx1.redhat.com ([209.132.183.28]:41365 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755256Ab3BVJx2 (ORCPT ); Fri, 22 Feb 2013 04:53:28 -0500 Message-ID: <51273FE3.8000306@redhat.com> Date: Fri, 22 Feb 2013 10:52:35 +0100 From: Ric Wheeler User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Paolo Bonzini CC: Zach Brown , "Myklebust, Trond" , Linux FS Devel , "linux-kernel@vger.kernel.org" , "Chris L. Mason" , Christoph Hellwig , Alexander Viro , "Martin K. Petersen" , Hannes Reinecke , Joel Becker Subject: Re: New copyfile system call - discuss before LSF? References: <512606DF.5050706@redhat.com> <4FA345DA4F4AE44899BD2B03EEEC2FA9235D998C@SACEXCMBX04-PRD.hq.netapp.com> <512635D2.4090207@redhat.com> <51267CEB.8070805@redhat.com> <4FA345DA4F4AE44899BD2B03EEEC2FA9235DAA99@SACEXCMBX04-PRD.hq.netapp.com> <20130221222449.GY22221@lenny.home.zabbo.net> <51273EBB.1010305@redhat.com> In-Reply-To: <51273EBB.1010305@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02/22/2013 10:47 AM, Paolo Bonzini wrote: > Il 21/02/2013 23:24, Zach Brown ha scritto: >> You could make it work with some locking and out_fd seeking to set the >> write offset before calling sendfile64()+flags, but ugh. >> >> ssize_t sendfile(int out_fd, int in_fd, off_t in_offset, off_t >> out_offset, size_t count, int flags); >> >> That seems closer. >> >> We might also want to pre-emptively offer iovs instead of offsets, >> because that's the very first thing that's going to be requested after >> people prototype having to iterate calling sendfile() for each >> contiguous copy region. > Indeed, I was about to propose that exactly. So that would be > psendfilev. I don't think psendfile is useful, and can be easily > provided at the libc level. > > Paolo This seems to be suspiciously close to a clear consensus on how to move forward after many years of spinning our wheels. Anyone want to promote an actual patch before we change our collective minds? Ric