From patchwork Sun Aug 21 02:29:45 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Allison Henderson X-Patchwork-Id: 110796 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id D43C5B6F75 for ; Sun, 21 Aug 2011 12:26:47 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755034Ab1HUC0q (ORCPT ); Sat, 20 Aug 2011 22:26:46 -0400 Received: from e6.ny.us.ibm.com ([32.97.182.146]:38777 "EHLO e6.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751532Ab1HUC0n (ORCPT ); Sat, 20 Aug 2011 22:26:43 -0400 Received: from d01relay07.pok.ibm.com (d01relay07.pok.ibm.com [9.56.227.147]) by e6.ny.us.ibm.com (8.14.4/8.13.1) with ESMTP id p7L22Xh6022414 for ; Sat, 20 Aug 2011 22:02:33 -0400 Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by d01relay07.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p7L2QgsC3125300 for ; Sat, 20 Aug 2011 22:26:42 -0400 Received: from d01av01.pok.ibm.com (loopback [127.0.0.1]) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p7L2QfK2008811 for ; Sat, 20 Aug 2011 22:26:41 -0400 Received: from elm3c80.beaverton.ibm.com ([9.47.69.80]) by d01av01.pok.ibm.com (8.14.4/8.13.1/NCO v10.0 AVin) with ESMTP id p7L2QcRn008765; Sat, 20 Aug 2011 22:26:41 -0400 From: Allison Henderson To: linux-ext4@vger.kernel.org Cc: Allison Henderson Subject: [PATCH 4/6 v5] ext4: Correct large hole offset calcuation Date: Sat, 20 Aug 2011 19:29:45 -0700 Message-Id: <1313893787-25460-5-git-send-email-achender@linux.vnet.ibm.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1313893787-25460-1-git-send-email-achender@linux.vnet.ibm.com> References: <1313893787-25460-1-git-send-email-achender@linux.vnet.ibm.com> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org This bug was reported by Lukas Czerner while working on a new patch to add discard support for loop devices using punch hole. The bug is happens because the data type for logical blocks is not large enough to calculate the block offset for holes that are very large. This bug is resolved by casting the ext4_lblk_t to an loff_t before calculating the byte offset of the block. Reviewed-and-Tested-by: Lukas Czerner Signed-off-by: Allison Henderson Reviewed-by: Eric Sandeen --- :100644 100644 0d7617d... b417e47... M fs/ext4/extents.c fs/ext4/extents.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 0d7617d..b417e47 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4179,8 +4179,8 @@ int ext4_ext_punch_hole(struct file *file, loff_t offset, loff_t length) EXT4_BLOCK_SIZE_BITS(sb); last_block = (offset + length) >> EXT4_BLOCK_SIZE_BITS(sb); - first_block_offset = first_block << EXT4_BLOCK_SIZE_BITS(sb); - last_block_offset = last_block << EXT4_BLOCK_SIZE_BITS(sb); + first_block_offset = ((loff_t)first_block) << EXT4_BLOCK_SIZE_BITS(sb); + last_block_offset = ((loff_t)last_block) << EXT4_BLOCK_SIZE_BITS(sb); first_page = (offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; last_page = (offset + length) >> PAGE_CACHE_SHIFT;