From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 97A77C54FCB for ; Thu, 23 Apr 2020 23:22:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6FFF32077D for ; Thu, 23 Apr 2020 23:22:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729035AbgDWXWE (ORCPT ); Thu, 23 Apr 2020 19:22:04 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:48480 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728183AbgDWXGc (ORCPT ); Thu, 23 Apr 2020 19:06:32 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1jRkvL-0004bi-JS; Fri, 24 Apr 2020 00:06:27 +0100 Received: from ben by deadeye with local (Exim 4.93) (envelope-from ) id 1jRkvK-00E6im-42; Fri, 24 Apr 2020 00:06:26 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Qu Wenruo" , "Mike Snitzer" Date: Fri, 24 Apr 2020 00:04:45 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 058/245] dm flakey: fix reads to be issued if drop_writes configured In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.83-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Mike Snitzer commit 299f6230bc6d0ccd5f95bb0fb865d80a9c7d5ccc upstream. v4.8-rc3 commit 99f3c90d0d ("dm flakey: error READ bios during the down_interval") overlooked the 'drop_writes' feature, which is meant to allow reads to be issued rather than errored, during the down_interval. Fixes: 99f3c90d0d ("dm flakey: error READ bios during the down_interval") Reported-by: Qu Wenruo Signed-off-by: Mike Snitzer Signed-off-by: Ben Hutchings --- drivers/md/dm-flakey.c | 27 ++++++++++++++++----------- 1 file changed, 16 insertions(+), 11 deletions(-) --- a/drivers/md/dm-flakey.c +++ b/drivers/md/dm-flakey.c @@ -291,15 +291,13 @@ static int flakey_map(struct dm_target * pb->bio_submitted = true; /* - * Map reads as normal only if corrupt_bio_byte set. + * Error reads if neither corrupt_bio_byte or drop_writes are set. + * Otherwise, flakey_end_io() will decide if the reads should be modified. */ if (bio_data_dir(bio) == READ) { - /* If flags were specified, only corrupt those that match. */ - if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == READ) && - all_corrupt_bio_flags_match(bio, fc)) - goto map_bio; - else + if (!fc->corrupt_bio_byte && !test_bit(DROP_WRITES, &fc->flags)) return -EIO; + goto map_bio; } /* @@ -336,14 +334,21 @@ static int flakey_end_io(struct dm_targe struct flakey_c *fc = ti->private; struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data)); - /* - * Corrupt successful READs while in down state. - */ if (!error && pb->bio_submitted && (bio_data_dir(bio) == READ)) { - if (fc->corrupt_bio_byte) + if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == READ) && + all_corrupt_bio_flags_match(bio, fc)) { + /* + * Corrupt successful matching READs while in down state. + */ corrupt_bio_data(bio, fc); - else + + } else if (!test_bit(DROP_WRITES, &fc->flags)) { + /* + * Error read during the down_interval if drop_writes + * wasn't configured. + */ return -EIO; + } } return error;