From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Mon, 21 May 2001 20:22:55 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Mon, 21 May 2001 20:22:44 -0400 Received: from asterix.hrz.tu-chemnitz.de ([134.109.132.84]:42459 "EHLO asterix.hrz.tu-chemnitz.de") by vger.kernel.org with ESMTP id ; Mon, 21 May 2001 20:22:38 -0400 Date: Tue, 22 May 2001 02:22:34 +0200 From: Ingo Oeser To: Alexander Viro Cc: Alan Cox , Pavel Machek , Richard Gooch , Matthew Wilcox , Andrew Clausen , Ben LaHaise , torvalds@transmeta.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: Re: [RFD w/info-PATCH] device arguments from lookup, partion code Message-ID: <20010522022234.T754@nightmaster.csn.tu-chemnitz.de> In-Reply-To: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2i In-Reply-To: ; from viro@math.psu.edu on Mon, May 21, 2001 at 05:51:08PM -0400 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, May 21, 2001 at 05:51:08PM -0400, Alexander Viro wrote: > Sure. But we have to do two syscalls only if ioctl has both in- and out- > arguments that way. Moreover, we are talking about non-trivial in- arguments. > How many of these are in hotspots? ioctl has actually 4 semantics: command only command + read command + write command + rw-transaction Separating these would be a first step. And yes, I consider each of them useful. command only: reset drive command + rw-transaction: "dear device please mangle this data" (crypto processors come to mind...) The other two are obviously needed and already accepted by all of you. Hotspots: crypto hardware or generally DSPs. Regards Ingo Oeser -- To the systems programmer, users and applications serve only to provide a test load.