From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Mike Snitzer , Kamal Mostafa Subject: [PATCH 3.8 036/166] dm thin: switch to read-only mode if metadata space is exhausted Date: Wed, 15 Jan 2014 13:50:50 -0800 Message-Id: <1389822780-4729-37-git-send-email-kamal@canonical.com> In-Reply-To: <1389822780-4729-1-git-send-email-kamal@canonical.com> References: <1389822780-4729-1-git-send-email-kamal@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.8.13.16 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Mike Snitzer commit 4a02b34e0cf1d0d0dd3737702841da4bf615a50a upstream. Switch the thin pool to read-only mode in alloc_data_block() if dm_pool_alloc_data_block() fails because the pool's metadata space is exhausted. Differentiate between data and metadata space in messages about no free space available. This issue was noticed with the device-mapper-test-suite using: dmtest run --suite thin-provisioning -n /exhausting_metadata_space_causes_fail_mode/ The quantity of errors logged in this case must be reduced. before patch: device-mapper: thin: 253:4: reached low water mark for metadata device: sending event. device-mapper: space map metadata: unable to allocate new metadata block device-mapper: space map common: dm_tm_shadow_block() failed device-mapper: space map metadata: unable to allocate new metadata block device-mapper: space map common: dm_tm_shadow_block() failed device-mapper: space map metadata: unable to allocate new metadata block device-mapper: space map common: dm_tm_shadow_block() failed device-mapper: space map metadata: unable to allocate new metadata block device-mapper: space map common: dm_tm_shadow_block() failed device-mapper: space map metadata: unable to allocate new metadata block device-mapper: space map common: dm_tm_shadow_block() failed device-mapper: space map metadata: unable to allocate new metadata block device-mapper: thin: 253:4: commit failed: error = -28 device-mapper: thin: 253:4: switching pool to read-only mode after patch: device-mapper: thin: 253:4: reached low water mark for metadata device: sending event. device-mapper: space map metadata: unable to allocate new metadata block device-mapper: thin: 253:4: no free metadata space available. device-mapper: thin: 253:4: switching pool to read-only mode Signed-off-by: Mike Snitzer Acked-by: Joe Thornber Signed-off-by: Kamal Mostafa --- drivers/md/dm-thin.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index a3d00dd..c29e967 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -878,7 +878,7 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result) * doing all this checking and return -ENOSPC. */ if (!free_blocks) { - DMWARN("%s: no free space available.", + DMWARN("%s: no free data space available.", dm_device_name(pool->pool_md)); spin_lock_irqsave(&pool->lock, flags); pool->no_free_space = 1; @@ -889,8 +889,16 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result) } r = dm_pool_alloc_data_block(pool->pmd, result); - if (r) + if (r) { + if (r == -ENOSPC && + !dm_pool_get_free_metadata_block_count(pool->pmd, &free_blocks) && + !free_blocks) { + DMWARN("%s: no free metadata space available.", + dm_device_name(pool->pool_md)); + set_pool_mode(pool, PM_READ_ONLY); + } return r; + } return 0; } -- 1.8.3.2