From patchwork Thu Dec 19 11:54:35 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 303475 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id DD5B12C0084 for ; Thu, 19 Dec 2013 23:09:10 +1100 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1VtcPa-0003YX-L1; Thu, 19 Dec 2013 12:09:06 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1VtcGK-0007HF-9G for kernel-team@lists.ubuntu.com; Thu, 19 Dec 2013 11:59:32 +0000 Received: from [188.250.212.249] (helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1VtcGJ-0006H8-UE; Thu, 19 Dec 2013 11:59:32 +0000 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.11 177/208] dm thin: allow pool in read-only mode to transition to read-write mode Date: Thu, 19 Dec 2013 11:54:35 +0000 Message-Id: <1387454106-19326-178-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1387454106-19326-1-git-send-email-luis.henriques@canonical.com> References: <1387454106-19326-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.11 Cc: Joe Thornber , Mike Snitzer X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.11.10.2 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Joe Thornber commit 9b7aaa64f96f7ca280d75326fca42f42017b89ef upstream. A thin-pool may be in read-only mode because the pool's data or metadata space was exhausted. To allow for recovery, by adding more space to the pool, we must allow a pool to transition from PM_READ_ONLY to PM_WRITE mode. Otherwise, running out of space will render the pool permanently read-only. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer [ luis: backported to 3.11: - adjusted context - dropped function dm_bm_prefetch() comments in file dm-block-manager.h ] Signed-off-by: Luis Henriques --- drivers/md/dm-thin-metadata.c | 8 ++++++++ drivers/md/dm-thin-metadata.h | 1 + drivers/md/dm-thin.c | 12 ++++++++++-- drivers/md/persistent-data/dm-block-manager.c | 6 ++++++ drivers/md/persistent-data/dm-block-manager.h | 1 + 5 files changed, 26 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c index 60bce43..8a30ad5 100644 --- a/drivers/md/dm-thin-metadata.c +++ b/drivers/md/dm-thin-metadata.c @@ -1697,6 +1697,14 @@ void dm_pool_metadata_read_only(struct dm_pool_metadata *pmd) up_write(&pmd->root_lock); } +void dm_pool_metadata_read_write(struct dm_pool_metadata *pmd) +{ + down_write(&pmd->root_lock); + pmd->read_only = false; + dm_bm_set_read_write(pmd->bm); + up_write(&pmd->root_lock); +} + int dm_pool_register_metadata_threshold(struct dm_pool_metadata *pmd, dm_block_t threshold, dm_sm_threshold_fn fn, diff --git a/drivers/md/dm-thin-metadata.h b/drivers/md/dm-thin-metadata.h index 845ebbe..7bcc0e1 100644 --- a/drivers/md/dm-thin-metadata.h +++ b/drivers/md/dm-thin-metadata.h @@ -193,6 +193,7 @@ int dm_pool_resize_metadata_dev(struct dm_pool_metadata *pmd, dm_block_t new_siz * that nothing is changing. */ void dm_pool_metadata_read_only(struct dm_pool_metadata *pmd); +void dm_pool_metadata_read_write(struct dm_pool_metadata *pmd); int dm_pool_register_metadata_threshold(struct dm_pool_metadata *pmd, dm_block_t threshold, diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index 930a7e3..203c104 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -1412,6 +1412,7 @@ static void set_pool_mode(struct pool *pool, enum pool_mode mode) break; case PM_WRITE: + dm_pool_metadata_read_write(pool->pmd); pool->process_bio = process_bio; pool->process_discard = process_discard; pool->process_prepared_mapping = process_prepared_mapping; @@ -1628,12 +1629,19 @@ static int bind_control_target(struct pool *pool, struct dm_target *ti) struct pool_c *pt = ti->private; /* - * We want to make sure that degraded pools are never upgraded. + * We want to make sure that a pool in PM_FAIL mode is never upgraded. */ enum pool_mode old_mode = pool->pf.mode; enum pool_mode new_mode = pt->adjusted_pf.mode; - if (old_mode > new_mode) + /* + * If we were in PM_FAIL mode, rollback of metadata failed. We're + * not going to recover without a thin_repair. So we never let the + * pool move out of the old mode. On the other hand a PM_READ_ONLY + * may have been due to a lack of metadata or data space, and may + * now work (ie. if the underlying devices have been resized). + */ + if (old_mode == PM_FAIL) new_mode = old_mode; pool->ti = ti; diff --git a/drivers/md/persistent-data/dm-block-manager.c b/drivers/md/persistent-data/dm-block-manager.c index 81b5138..44bcc76 100644 --- a/drivers/md/persistent-data/dm-block-manager.c +++ b/drivers/md/persistent-data/dm-block-manager.c @@ -621,6 +621,12 @@ void dm_bm_set_read_only(struct dm_block_manager *bm) } EXPORT_SYMBOL_GPL(dm_bm_set_read_only); +void dm_bm_set_read_write(struct dm_block_manager *bm) +{ + bm->read_only = false; +} +EXPORT_SYMBOL_GPL(dm_bm_set_read_write); + u32 dm_bm_checksum(const void *data, size_t len, u32 init_xor) { return crc32c(~(u32) 0, data, len) ^ init_xor; diff --git a/drivers/md/persistent-data/dm-block-manager.h b/drivers/md/persistent-data/dm-block-manager.h index be5bff6..84dbab5 100644 --- a/drivers/md/persistent-data/dm-block-manager.h +++ b/drivers/md/persistent-data/dm-block-manager.h @@ -120,6 +120,7 @@ int dm_bm_flush_and_unlock(struct dm_block_manager *bm, * be returned if you do. */ void dm_bm_set_read_only(struct dm_block_manager *bm); +void dm_bm_set_read_write(struct dm_block_manager *bm); u32 dm_bm_checksum(const void *data, size_t len, u32 init_xor);