From patchwork Mon Jul 17 23:56:52 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Verma, Vishal L" X-Patchwork-Id: 9846493 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 9D7B560386 for ; Mon, 17 Jul 2017 23:58:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B63BA2621B for ; Mon, 17 Jul 2017 23:58:39 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AB2CC26E49; Mon, 17 Jul 2017 23:58:39 +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=-1.9 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_NONE autolearn=ham version=3.3.1 Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 77FF62621B for ; Mon, 17 Jul 2017 23:58:39 +0000 (UTC) Received: from [127.0.0.1] (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id A039521CB030D; Mon, 17 Jul 2017 16:56:43 -0700 (PDT) X-Original-To: linux-nvdimm@lists.01.org Delivered-To: linux-nvdimm@lists.01.org Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id 66D8B2193B802 for ; Mon, 17 Jul 2017 16:56:42 -0700 (PDT) Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Jul 2017 16:58:35 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.40,376,1496127600"; d="scan'208";a="127844238" Received: from omniknight.lm.intel.com ([10.232.112.78]) by fmsmga005.fm.intel.com with ESMTP; 17 Jul 2017 16:58:35 -0700 From: Vishal Verma To: Subject: [PATCH v3 3/6] btt: ensure that flags were also unchanged during a map_read Date: Mon, 17 Jul 2017 17:56:52 -0600 Message-Id: <20170717235655.26424-4-vishal.l.verma@intel.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20170717235655.26424-1-vishal.l.verma@intel.com> References: <20170717235655.26424-1-vishal.l.verma@intel.com> X-BeenThere: linux-nvdimm@lists.01.org X-Mailman-Version: 2.1.22 Precedence: list List-Id: "Linux-nvdimm developer list." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Rafael J. Wysocki" MIME-Version: 1.0 Errors-To: linux-nvdimm-bounces@lists.01.org Sender: "Linux-nvdimm" X-Virus-Scanned: ClamAV using ClamSMTP In btt_map_read, we read the map twice to make sure that the map entry didn't change after we added it to the read tracking table. In anticipation of expanding the use of the error bit, also make sure that the error and zero flags are constant across the two map reads. Signed-off-by: Vishal Verma --- drivers/nvdimm/btt.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c index 3aa6bc0..304dac4 100644 --- a/drivers/nvdimm/btt.c +++ b/drivers/nvdimm/btt.c @@ -1031,6 +1031,7 @@ static int btt_read_pg(struct btt *btt, struct bio_integrity_payload *bip, */ while (1) { u32 new_map; + int new_t, new_e; if (t_flag) { zero_fill_data(page, off, cur_len); @@ -1049,15 +1050,18 @@ static int btt_read_pg(struct btt *btt, struct bio_integrity_payload *bip, */ barrier(); - ret = btt_map_read(arena, premap, &new_map, &t_flag, - &e_flag, NVDIMM_IO_ATOMIC); + ret = btt_map_read(arena, premap, &new_map, &new_t, + &new_e, NVDIMM_IO_ATOMIC); if (ret) goto out_rtt; - if (postmap == new_map) + if ((postmap == new_map) && (t_flag == new_t) && + (e_flag == new_e)) break; postmap = new_map; + t_flag = new_t; + e_flag = new_e; } ret = btt_data_read(arena, page, off, postmap, cur_len);