From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752348Ab2D3F6F (ORCPT ); Mon, 30 Apr 2012 01:58:05 -0400 Received: from out1-smtp.messagingengine.com ([66.111.4.25]:56462 "EHLO out1-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751510Ab2D3F6D (ORCPT ); Mon, 30 Apr 2012 01:58:03 -0400 X-Sasl-enc: L0q4Q1621lF9AKie7JvQHqP1JvAgEPbMDhcIm7waRaszeQQySJFNZqv1aw 1335765482 Message-ID: <1335765478.2281.13.camel@perseus.themaw.net> Subject: Re: autofs: make the autofsv5 packet file descriptor use a packetized pipe From: Ian Kent To: Linus Torvalds Cc: "H. Peter Anvin" , Linux Kernel Mailing List , Michael Tokarev , Alan Cox , Thomas Meyer , autofs@vger.kernel.org Date: Mon, 30 Apr 2012 13:57:58 +0800 In-Reply-To: References: <20120429205429.63CCD7C0064@ra.kernel.org> <4F9DD994.70202@zytor.com> <4F9DDCB6.1070908@zytor.com> <4F9DDE47.5060008@zytor.com> <1335749398.2281.0.camel@perseus.themaw.net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3 (3.2.3-2.fc16) Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2012-04-29 at 18:56 -0700, Linus Torvalds wrote: > On Sun, Apr 29, 2012 at 6:29 PM, Ian Kent wrote: > > > > autodir looks ok as well. > > > > http://sourceforge.net/projects/intraperson/files/latest/download > > That looks odd, but safe. > > Why does the code make the pipe file descriptor non-blocking, when it > then always reads it using that odd "poll_read()" function that does a > loop with poll() and read(). I guess there is some 1-second timeout > thing. > > It's a bit odd in other ways too. The "handle_events()" function is > passed the fd, but then it never actually uses it, and uses > 'autodir.k_pipe' instead. > > So I'm having a bit of trouble following the *logic* to any of that, > but the only reads I found did seem to match the "read whole packet" > model, so it does look ok too. I'm only aware that autodir uses the module and wasn't involved in the development. I didn't look closely at it at all, just enough to check for reads to the kernel pipe, so I don't know either. I'm not sure that autodir is still maintained so the only thing I'll do is include a cc to the autodir mailing list in a any follow up mail to the autofs list explaining the outcome of this work. Ian