From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262600AbTDUVbK (ORCPT ); Mon, 21 Apr 2003 17:31:10 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262609AbTDUVbK (ORCPT ); Mon, 21 Apr 2003 17:31:10 -0400 Received: from hera.cwi.nl ([192.16.191.8]:37594 "EHLO hera.cwi.nl") by vger.kernel.org with ESMTP id S262600AbTDUVbI (ORCPT ); Mon, 21 Apr 2003 17:31:08 -0400 From: Andries.Brouwer@cwi.nl Date: Mon, 21 Apr 2003 23:43:06 +0200 (MEST) Message-Id: To: torvalds@transmeta.com, viro@parcelfarce.linux.theplanet.co.uk Subject: Re: [PATCH] new system call mknod64 Cc: Andries.Brouwer@cwi.nl, davem@redhat.com, hch@infradead.org, linux-kernel@vger.kernel.org, zippel@linux-m68k.org Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Nice to see this discussion. Linus says > The question is only _where_ (not whether) we do the mapping. Right now we > keep "dev_t" in the same format as we give back to user space, and thus we > always map into that format internally. But we don't have to: we can have > an internal format that is different from the one we show users. and in fact the patches I have been giving out use kdev_t as internal format, where you can think of kdev_t as u64, or, if you prefer, as struct { u32 major, minor; }. As I wrote a month or two ago, my favourite version is to have register_region work in the kdev_t space, rather than the dev_t space, since intervals in kdev_t space have a direct interpretation in terms of major, minor. Andries (Both versions do not differ very much; as far as I am concerned the choice is not very important, but the kdev_t version is slightly cleaner.) (As Al already remarked, device numbers do not play much of a role internally. I removed i_dev. We still have i_rdev.)