From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758603AbZASDIB (ORCPT ); Sun, 18 Jan 2009 22:08:01 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757682AbZASDHt (ORCPT ); Sun, 18 Jan 2009 22:07:49 -0500 Received: from palinux.external.hp.com ([192.25.206.14]:52485 "EHLO mail.parisc-linux.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757667AbZASDHs (ORCPT ); Sun, 18 Jan 2009 22:07:48 -0500 Date: Sun, 18 Jan 2009 20:07:32 -0700 From: Matthew Wilcox To: "Gao, Yunpeng" Cc: "linux-ia64@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: your mail Message-ID: <20090119030731.GA28670@parisc-linux.org> References: <38D9F46DFF92C54980D2F2C1E8EE31301FC5E7FB@pdsmsx503.ccr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <38D9F46DFF92C54980D2F2C1E8EE31301FC5E7FB@pdsmsx503.ccr.corp.intel.com> User-Agent: Mutt/1.5.13 (2006-08-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jan 19, 2009 at 10:54:02AM +0800, Gao, Yunpeng wrote: > I have to use 64bit variable in my 2.6.27 kernel NAND driver as below: > --------------------------------------------------------------------------- > u64 NAND_capacity; > unsigned int block_num, block_size; > ... > block_num = NAND_capacity / block_size; > --------------------------------------------------------------------------- > but it failed when compiling and reports 'undefined reference to `__udivdi3'. Presumably block_size is a power of two, so you can do: block_num = NAND_capacity >> block_shift; -- Matthew Wilcox Intel Open Source Technology Centre "Bill, look, we understand that you're interested in selling us this operating system, but compare it to ours. We can't possibly take such a retrograde step."