From b53306558526a097a587774573b76d0d9903c5bf Mon Sep 17 00:00:00 2001 From: Joe Thornber Date: Wed, 4 Dec 2013 19:51:33 -0500 Subject: [PATCH] dm thin: handle metadata failures more consistently Introduce metadata_operation_failed() wrappers, around set_pool_mode(), to assist with improving the consistency of how metadata failures are handled. Logging is improved and metadata operation failures trigger read-only mode immediately. Also, eliminate redundant set_pool_mode() calls in the two alloc_data_block() caller's error paths. Signed-off-by: Joe Thornber Signed-off-by: Mike Snitzer --- drivers/md/dm-thin.c | 48 +++++++++++++++++++++++++------------------- 1 file changed, 27 insertions(+), 21 deletions(-) diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c index e49c27c91a1f..35d2e41ef82f 100644 --- a/drivers/md/dm-thin.c +++ b/drivers/md/dm-thin.c @@ -198,7 +198,7 @@ struct pool { }; static enum pool_mode get_pool_mode(struct pool *pool); -static void set_pool_mode(struct pool *pool, enum pool_mode mode); +static void metadata_operation_failed(struct pool *pool, const char *op, int r); /* * Target context for a pool. @@ -641,9 +641,7 @@ static void process_prepared_mapping(struct dm_thin_new_mapping *m) */ r = dm_thin_insert_block(tc->td, m->virt_block, m->data_block); if (r) { - DMERR_LIMIT("%s: dm_thin_insert_block() failed: error = %d", - dm_device_name(pool->pool_md), r); - set_pool_mode(pool, PM_READ_ONLY); + metadata_operation_failed(pool, "dm_thin_insert_block", r); cell_error(pool, m->cell); goto out; } @@ -900,11 +898,8 @@ static int commit(struct pool *pool) return -EINVAL; r = dm_pool_commit_metadata(pool->pmd); - if (r) { - DMERR_LIMIT("%s: dm_pool_commit_metadata failed: error = %d", - dm_device_name(pool->pool_md), r); - set_pool_mode(pool, PM_READ_ONLY); - } + if (r) + metadata_operation_failed(pool, "dm_pool_commit_metadata", r); return r; } @@ -941,8 +936,10 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result) return -EINVAL; r = dm_pool_get_free_block_count(pool->pmd, &free_blocks); - if (r) + if (r) { + metadata_operation_failed(pool, "dm_pool_get_free_block_count", r); return r; + } check_low_water_mark(pool, free_blocks); @@ -956,8 +953,10 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result) return r; r = dm_pool_get_free_block_count(pool->pmd, &free_blocks); - if (r) + if (r) { + metadata_operation_failed(pool, "dm_pool_get_free_block_count", r); return r; + } /* * If we still have no space we set a flag to avoid @@ -980,11 +979,11 @@ static int alloc_data_block(struct thin_c *tc, dm_block_t *result) if (r) { if (r == -ENOSPC && !dm_pool_get_free_metadata_block_count(pool->pmd, &free_blocks) && - !free_blocks) { + !free_blocks) DMWARN("%s: no free metadata space available.", dm_device_name(pool->pool_md)); - set_pool_mode(pool, PM_READ_ONLY); - } + + metadata_operation_failed(pool, "dm_pool_alloc_data_block", r); return r; } @@ -1126,7 +1125,6 @@ static void break_sharing(struct thin_c *tc, struct bio *bio, dm_block_t block, default: DMERR_LIMIT("%s: alloc_data_block() failed: error = %d", __func__, r); - set_pool_mode(pool, PM_READ_ONLY); cell_error(pool, cell); break; } @@ -1205,7 +1203,6 @@ static void provision_block(struct thin_c *tc, struct bio *bio, dm_block_t block default: DMERR_LIMIT("%s: alloc_data_block() failed: error = %d", __func__, r); - set_pool_mode(pool, PM_READ_ONLY); cell_error(pool, cell); break; } @@ -1449,6 +1446,18 @@ static void set_pool_mode(struct pool *pool, enum pool_mode mode) } } +/* + * Rather than calling set_pool_mode directly, use these which describe the + * reason for mode degradation. + */ +static void metadata_operation_failed(struct pool *pool, const char *op, int r) +{ + DMERR_LIMIT("%s: metadata operation '%s' failed: error = %d", + dm_device_name(pool->pool_md), op, r); + + set_pool_mode(pool, PM_READ_ONLY); +} + /*----------------------------------------------------------------*/ /* @@ -2209,9 +2218,7 @@ static int maybe_resize_data_dev(struct dm_target *ti, bool *need_commit) } else if (data_size > sb_data_size) { r = dm_pool_resize_data_dev(pool->pmd, data_size); if (r) { - DMERR("%s: failed to resize data device", - dm_device_name(pool->pool_md)); - set_pool_mode(pool, PM_READ_ONLY); + metadata_operation_failed(pool, "dm_pool_resize_data_dev", r); return r; } @@ -2248,8 +2255,7 @@ static int maybe_resize_metadata_dev(struct dm_target *ti, bool *need_commit) } else if (metadata_dev_size > sb_metadata_dev_size) { r = dm_pool_resize_metadata_dev(pool->pmd, metadata_dev_size); if (r) { - DMERR("%s: failed to resize metadata device", - dm_device_name(pool->pool_md)); + metadata_operation_failed(pool, "dm_pool_resize_metadata_dev", r); return r; }