From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933057AbbA2D1S (ORCPT ); Wed, 28 Jan 2015 22:27:18 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:46923 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755522AbbA2CfQ (ORCPT ); Wed, 28 Jan 2015 21:35:16 -0500 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Joe Thornber , Mike Snitzer , Kamal Mostafa Subject: [PATCH 3.13.y-ckt 059/139] dm cache: only use overwrite optimisation for promotion when in writeback mode Date: Wed, 28 Jan 2015 14:20:02 -0800 Message-Id: <1422483682-15393-60-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1422483682-15393-1-git-send-email-kamal@canonical.com> References: <1422483682-15393-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.13.11-ckt15 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Joe Thornber commit f29a3147e251d7ae20d3194ff67f109d71e501b4 upstream. Overwrite causes the cache block and origin blocks to diverge, which is only allowed in writeback mode. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer Signed-off-by: Kamal Mostafa --- drivers/md/dm-cache-target.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index 99474ef..b943ef1 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -1049,7 +1049,8 @@ static void issue_copy(struct dm_cache_migration *mg) avoid = is_discarded_oblock(cache, mg->new_oblock); - if (!avoid && bio_writes_complete_block(cache, bio)) { + if (writeback_mode(&cache->features) && + !avoid && bio_writes_complete_block(cache, bio)) { issue_overwrite(mg, bio); return; } -- 1.9.1