From patchwork Mon Aug 21 11:54:53 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jan Kara X-Patchwork-Id: 9912297 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 666F4602D8 for ; Mon, 21 Aug 2017 11:55:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4D77627FA8 for ; Mon, 21 Aug 2017 11:55:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 422C5286E4; Mon, 21 Aug 2017 11:55:26 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A82F327FA8 for ; Mon, 21 Aug 2017 11:55:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753600AbdHULzY (ORCPT ); Mon, 21 Aug 2017 07:55:24 -0400 Received: from mx2.suse.de ([195.135.220.15]:32768 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752462AbdHULzU (ORCPT ); Mon, 21 Aug 2017 07:55:20 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 3E112AC54; Mon, 21 Aug 2017 11:55:19 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id D175B1E3435; Mon, 21 Aug 2017 13:55:18 +0200 (CEST) From: Jan Kara To: Cc: Wang Shilong , Andreas Dilger , Jan Kara Subject: [PATCH 03/27] quota: Acquire dqio_sem for reading in dquot_get_next_id() Date: Mon, 21 Aug 2017 13:54:53 +0200 Message-Id: <20170821115517.26542-4-jack@suse.cz> X-Mailer: git-send-email 2.12.3 In-Reply-To: <20170821115517.26542-1-jack@suse.cz> References: <20170821115517.26542-1-jack@suse.cz> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP dquot_get_next_id() needs dqio_sem only for reading to protect against racing with modification of quota file structure. Reviewed-by: Andreas Dilger Signed-off-by: Jan Kara --- fs/quota/dquot.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c index 21358f31923d..8d5ccad3bf3e 100644 --- a/fs/quota/dquot.c +++ b/fs/quota/dquot.c @@ -2079,9 +2079,9 @@ int dquot_get_next_id(struct super_block *sb, struct kqid *qid) return -ESRCH; if (!dqopt->ops[qid->type]->get_next_id) return -ENOSYS; - down_write(&dqopt->dqio_sem); + down_read(&dqopt->dqio_sem); err = dqopt->ops[qid->type]->get_next_id(sb, qid); - up_write(&dqopt->dqio_sem); + up_read(&dqopt->dqio_sem); return err; } EXPORT_SYMBOL(dquot_get_next_id);