From patchwork Fri Jan 16 18:08:12 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 19016 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id 6B7A8474C7 for ; Sat, 17 Jan 2009 05:08:34 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932518AbZAPSIb (ORCPT ); Fri, 16 Jan 2009 13:08:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762930AbZAPSIY (ORCPT ); Fri, 16 Jan 2009 13:08:24 -0500 Received: from styx.suse.cz ([82.119.242.94]:47978 "EHLO mail.suse.cz" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1761813AbZAPSIW (ORCPT ); Fri, 16 Jan 2009 13:08:22 -0500 Received: from duck.suse.cz (duck.suse.cz [10.20.1.74]) by mail.suse.cz (Postfix) with ESMTP id C9A25628127; Fri, 16 Jan 2009 19:08:20 +0100 (CET) Received: by duck.suse.cz (Postfix, from userid 10005) id A89381F1E2E; Fri, 16 Jan 2009 19:08:20 +0100 (CET) From: Jan Kara To: linux-kernel@vger.kernel.org Cc: linux-ext4@vger.kernel.org, linux-fsdevel@vger.kernel.org, Jan Kara Subject: [PATCH 04/11] ocfs2: Fix possible deadlock in ocfs2_write_dquot() Date: Fri, 16 Jan 2009 19:08:12 +0100 Message-Id: <1232129299-22018-5-git-send-email-jack@suse.cz> X-Mailer: git-send-email 1.6.0.2 In-Reply-To: <1232129299-22018-4-git-send-email-jack@suse.cz> References: <1232129299-22018-1-git-send-email-jack@suse.cz> <1232129299-22018-2-git-send-email-jack@suse.cz> <1232129299-22018-3-git-send-email-jack@suse.cz> <1232129299-22018-4-git-send-email-jack@suse.cz> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org It could happen that some limit has been set via quotactl() and in parallel ->mark_dirty() is called from another thread doing e.g. dquot_alloc_space(). In such case ocfs2_write_dquot() must not try to sync the dquot because that needs global quota lock but that ranks above transaction start. Signed-off-by: Jan Kara Acked-by: Mark Fasheh --- fs/ocfs2/quota_global.c | 4 +++- 1 files changed, 3 insertions(+), 1 deletions(-) diff --git a/fs/ocfs2/quota_global.c b/fs/ocfs2/quota_global.c index f4efa89..1ed0f7c 100644 --- a/fs/ocfs2/quota_global.c +++ b/fs/ocfs2/quota_global.c @@ -754,7 +754,9 @@ static int ocfs2_mark_dquot_dirty(struct dquot *dquot) if (dquot->dq_flags & mask) sync = 1; spin_unlock(&dq_data_lock); - if (!sync) { + /* This is a slight hack but we can't afford getting global quota + * lock if we already have a transaction started. */ + if (!sync || journal_current_handle()) { status = ocfs2_write_dquot(dquot); goto out; }