From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 14 Jun 2001 10:33:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 14 Jun 2001 10:33:03 -0400 Received: from panic.ohr.gatech.edu ([130.207.47.194]:7823 "HELO havoc.gtf.org") by vger.kernel.org with SMTP id ; Thu, 14 Jun 2001 10:33:01 -0400 Message-ID: <3B28CB1A.E8226801@mandrakesoft.com> Date: Thu, 14 Jun 2001 10:32:58 -0400 From: Jeff Garzik Organization: MandrakeSoft X-Mailer: Mozilla 4.77 [en] (X11; U; Linux 2.4.6-pre3 i686) X-Accept-Language: en MIME-Version: 1.0 To: "David S. Miller" Cc: Tom Gall , linux-kernel@vger.kernel.org Subject: Re: Going beyond 256 PCI buses In-Reply-To: <3B273A20.8EE88F8F@vnet.ibm.com> <3B28C6C1.3477493F@mandrakesoft.com> <15144.51504.8399.395200@pizda.ninka.net> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org "David S. Miller" wrote: > 1) Extending the type bus numbers use inside the kernel. > > Basically how most multi-controller platforms work now > is they allocate bus numbers in the 256 bus space as > controllers are probed. If we change the internal type > used by the kernel to "u32" or whatever, we expand that > available space accordingly. > > For the lazy, basically go into include/linux/pci.h > and change the "unsigned char"s in struct pci_bus into > some larger type. This is mindless work. Why do you want to make the bus number larger than the PCI bus number register? It seems like adding 'unsigned int domain_num' makes more sense, and is more correct. Maybe that implies fixing up other code to use a (domain,bus) pair, but that's IMHO a much better change than totally changing the interpretation of pci_bus::bus_number... > 2) Figure out what to do wrt. sys_pciconfig_{read,write}() 3) (tiny issue) Change pci_dev::slot_name such that it includes the domain number. This is passed to userspace by SCSI and net drivers as a way to allow userspace to associate a kernel interface with a bus device. > Basically, this 256 bus limit in Linux is a complete fallacy. yep Regards, Jeff -- Jeff Garzik | Andre the Giant has a posse. Building 1024 | MandrakeSoft |