Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756678Ab3GZHIM (ORCPT ); Fri, 26 Jul 2013 03:08:12 -0400 Received: from mail-pa0-f49.google.com ([209.85.220.49]:35291 "EHLO mail-pa0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753432Ab3GZHII (ORCPT ); Fri, 26 Jul 2013 03:08:08 -0400 Date: Fri, 26 Jul 2013 15:08:00 +0800 From: majianpeng To: viro Cc: linux-fsdevel , linux-kernel Reply-To: majianpeng Subject: question about splice X-Priority: 3 X-GUID: 0D9A8E2F-D084-42A7-84C3-B46CF744C738 X-Has-Attach: no X-Mailer: Foxmail 7.0.1.90[en] Mime-Version: 1.0 Message-ID: <201307261507562231224@gmail.com> Content-Type: text/plain; charset="gb2312" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id r6Q78KiT009437 Content-Length: 655 Lines: 15 Hi all, I used splice and found a prolem(at least i call). The demo is: A:splice(regularfileA--->pipe); B:splice(pipe--->regularfileB) Before do B, we modify the data of regA which now in pipe. The data to regularfileB willbe change. If we used the buff A:read(regA, buff); B: write(buff, regB); After A, the contend of regA can't effect the buff. Review the code of splice,I know the pipe share the pagecache of regA. Maybe this is not a problem or am i missing something? Thanks! Jianpeng Ma????{.n?+???????+%?????ݶ??w??{.n?+????{??G?????{ay?ʇڙ?,j??f???h?????????z_??(?階?ݢj"???m??????G????????????&???~???iO???z??v?^?m???? ????????I?