From: Curt Wohlgemuth Subject: Question on huge_file Date: Fri, 10 Jul 2009 08:32:12 -0700 Message-ID: <6601abe90907100832q6ab886f2r7fc8e3be2a79e8e5@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: ext4 development Return-path: Received: from smtp-out.google.com ([216.239.33.17]:13898 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751401AbZGJPcR (ORCPT ); Fri, 10 Jul 2009 11:32:17 -0400 Received: from zps77.corp.google.com (zps77.corp.google.com [172.25.146.77]) by smtp-out.google.com with ESMTP id n6AFWE6X005397 for ; Fri, 10 Jul 2009 16:32:15 +0100 Received: from pxi14 (pxi14.prod.google.com [10.243.27.14]) by zps77.corp.google.com with ESMTP id n6AFWClg019591 for ; Fri, 10 Jul 2009 08:32:12 -0700 Received: by pxi14 with SMTP id 14so666790pxi.10 for ; Fri, 10 Jul 2009 08:32:12 -0700 (PDT) Sender: linux-ext4-owner@vger.kernel.org List-ID: I apologize if this is a dumb question, but I'm having trouble understanding the huge_file superblock flag. I see how, if this flag is set, that the inode can have a size > 2**32 bytes, using the i_size_lo/i_size_high fields. But since an ext4_extent only uses 32-bits for for its ee_block field to represent the logical block, how can an extent describe any block range of a file past the 4GiB boundary? Am I missing something? Thanks, Curt