Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 20 Apr 2001 08:26:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 20 Apr 2001 08:26:09 -0400 Received: from samba.sourceforge.net ([198.186.203.85]:44050 "HELO lists.samba.org") by vger.kernel.org with SMTP id ; Fri, 20 Apr 2001 08:25:53 -0400 From: Paul Mackerras MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15072.11026.385642.667425@argo.ozlabs.ibm.com.au> Date: Fri, 20 Apr 2001 22:26:58 +1000 (EST) To: tom_gall@vnet.ibm.com Cc: linux-kernel@vger.kernel.org Subject: Re: pmd_alloc, pte_alloc, Was Re: 2.4.3 and Alpha In-Reply-To: <3AD77FBF.874F8305@vnet.ibm.com> In-Reply-To: <3AD77FBF.874F8305@vnet.ibm.com> X-Mailer: VM 6.75 under Emacs 20.4.1 Reply-To: paulus@samba.org Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org tom_gall@vnet.ibm.com writes: > Basically in the pmd, it would seem that the current design in 2.4.3 forces > you to have pointers in there. Currently in our source we're using offsets > instead of a 64 bit pointer... this of course saved us from having to alloc 2 > contiguous pages in memory. Nope, the representation of the pgd/pmd/pte entries is entirely up to you (us :). The pmd entries for example are accessed through pmd_none, pmd_present, pte_offset, etc., and are set with pmd_populate. Those functions are all defined in asm/pgtable.h and asm/pgalloc.c. So you can make the representation whatever you like as long as those functions all do the right thing. Same goes for the pgd and pte levels. Paul. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/