Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751942AbdFSSdw (ORCPT + 2 others); Mon, 19 Jun 2017 14:33:52 -0400 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:51741 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751789AbdFSSdu (ORCPT ); Mon, 19 Jun 2017 14:33:50 -0400 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux@roeck-us.net Cc: Jan Kara , "Theodore Ts'o" , Willy Tarreau Subject: [PATCH 3.10 009/268] ext4: trim allocation requests to group size Date: Mon, 19 Jun 2017 20:28:28 +0200 Message-Id: <1497897167-14556-10-git-send-email-w@1wt.eu> X-Mailer: git-send-email 2.8.0.rc2.1.gbe9624a In-Reply-To: <1497897167-14556-1-git-send-email-w@1wt.eu> References: <1497897167-14556-1-git-send-email-w@1wt.eu> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: From: Jan Kara commit cd648b8a8fd5071d232242d5ee7ee3c0815776af upstream. If filesystem groups are artifically small (using parameter -g to mkfs.ext4), ext4_mb_normalize_request() can result in a request that is larger than a block group. Trim the request size to not confuse allocation code. Reported-by: "Kirill A. Shutemov" Signed-off-by: Jan Kara Signed-off-by: Theodore Ts'o Signed-off-by: Willy Tarreau --- fs/ext4/mballoc.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 83ed61a..cba1fc6 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -3063,6 +3063,13 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, if (ar->pright && start + size - 1 >= ar->lright) size -= start + size - ar->lright; + /* + * Trim allocation request for filesystems with artificially small + * groups. + */ + if (size > EXT4_BLOCKS_PER_GROUP(ac->ac_sb)) + size = EXT4_BLOCKS_PER_GROUP(ac->ac_sb); + end = start + size; /* check we don't cross already preallocated blocks */ -- 2.8.0.rc2.1.gbe9624a