From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752304AbdIIW74 (ORCPT ); Sat, 9 Sep 2017 18:59:56 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:43076 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752279AbdIIW7w (ORCPT ); Sat, 9 Sep 2017 18:59:52 -0400 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, "Joe Thornber" , "Mike Snitzer" Date: Sat, 09 Sep 2017 22:47:14 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.16 026/233] dm space map disk: fix some book keeping in the disk space map In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 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 List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.48-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Joe Thornber commit 0377a07c7a035e0d033cd8b29f0cb15244c0916a upstream. When decrementing the reference count for a block, the free count wasn't being updated if the reference count went to zero. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Signed-off-by: Ben Hutchings --- drivers/md/persistent-data/dm-space-map-disk.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) --- a/drivers/md/persistent-data/dm-space-map-disk.c +++ b/drivers/md/persistent-data/dm-space-map-disk.c @@ -140,10 +140,23 @@ static int sm_disk_inc_block(struct dm_s static int sm_disk_dec_block(struct dm_space_map *sm, dm_block_t b) { + int r; + uint32_t old_count; enum allocation_event ev; struct sm_disk *smd = container_of(sm, struct sm_disk, sm); - return sm_ll_dec(&smd->ll, b, &ev); + r = sm_ll_dec(&smd->ll, b, &ev); + if (!r && (ev == SM_FREE)) { + /* + * It's only free if it's also free in the last + * transaction. + */ + r = sm_ll_lookup(&smd->old_ll, b, &old_count); + if (!r && !old_count) + smd->nr_allocated_this_transaction--; + } + + return r; } static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b)