From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753851AbZH3QTw (ORCPT ); Sun, 30 Aug 2009 12:19:52 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753678AbZH3QTv (ORCPT ); Sun, 30 Aug 2009 12:19:51 -0400 Received: from mail-gx0-f205.google.com ([209.85.217.205]:43682 "EHLO mail-gx0-f205.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753408AbZH3QTv (ORCPT ); Sun, 30 Aug 2009 12:19:51 -0400 From: Nitin Gupta Reply-To: ngupta@vflare.org To: Andrew Morton Subject: [PATCH] swap: Fix swap size in case of block devices Date: Sun, 30 Aug 2009 21:49:10 +0530 User-Agent: KMail/1.12.0 (Linux/2.6.29.6-217.2.16.fc11.x86_64; KDE/4.3.0; x86_64; ; ) Cc: Rik van Riel , linux-kernel@vger.kernel.org, linux-mm@kvack.org MIME-Version: 1.0 Content-Type: Text/Plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Message-Id: <200908302149.10981.ngupta@vflare.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org During swapon, swap size is set to number of usable pages in the given swap file/block device minus 1 (for header page). In case of block devices, this size is incorrectly set as one page less than the actual due to an off-by-one error. For regular files, this size is set correctly. Signed-off-by: Nitin Gupta --- mm/swapfile.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/swapfile.c b/mm/swapfile.c index 8ffdc0d..3d37b97 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1951,9 +1951,9 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) if (error) goto bad_swap; + /* excluding header page */ nr_good_pages = swap_header->info.last_page - - swap_header->info.nr_badpages - - 1 /* header page */; + swap_header->info.nr_badpages; if (nr_good_pages) { swap_map[0] = SWAP_MAP_BAD;