diff options
| -rw-r--r-- | fs/btrfs/tests/extent-map-tests.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c index e6f0dd18392e..16830bf88f46 100644 --- a/fs/btrfs/tests/extent-map-tests.c +++ b/fs/btrfs/tests/extent-map-tests.c @@ -182,6 +182,79 @@ out: free_extent_map_tree(em_tree); } +static void __test_case_3(struct extent_map_tree *em_tree, u64 start) +{ + struct extent_map *em; + u64 len = SZ_4K; + int ret; + + em = alloc_extent_map(); + if (!em) + /* Skip this test on error. */ + return; + + /* Add [4K, 8K) */ + em->start = SZ_4K; + em->len = SZ_4K; + em->block_start = SZ_4K; + em->block_len = SZ_4K; + ret = add_extent_mapping(em_tree, em, 0); + ASSERT(ret == 0); + free_extent_map(em); + + em = alloc_extent_map(); + if (!em) + goto out; + + /* Add [0, 16K) */ + em->start = 0; + em->len = SZ_16K; + em->block_start = 0; + em->block_len = SZ_16K; + ret = btrfs_add_extent_mapping(em_tree, &em, start, len); + if (ret) + test_msg("case3 [0x%llx 0x%llx): ret %d\n", + start, start + len, ret); + /* + * Since bytes within em are contiguous, em->block_start is identical to + * em->start. + */ + if (em && + (start < em->start || start + len > extent_map_end(em) || + em->start != em->block_start || em->len != em->block_len)) + test_msg( +"case3 [0x%llx 0x%llx): ret %d em (start 0x%llx len 0x%llx block_start 0x%llx block_len 0x%llx)\n", + start, start + len, ret, em->start, em->len, + em->block_start, em->block_len); + free_extent_map(em); +out: + /* free memory */ + free_extent_map_tree(em_tree); +} + +/* + * Test scenario: + * + * Suppose that no extent map has been loaded into memory yet. + * There is a file extent [0, 16K), two jobs are running concurrently + * against it, t1 is buffered writing to [4K, 8K) and t2 is doing dio + * read from [0, 4K) or [8K, 12K) or [12K, 16K). + * + * t1 goes ahead of t2 and adds em [4K, 8K) into tree. + * + * t1 t2 + * cow_file_range() btrfs_get_extent() + * -> lookup_extent_mapping() + * -> add_extent_mapping() + * -> add_extent_mapping() + */ +static void test_case_3(struct extent_map_tree *em_tree) +{ + __test_case_3(em_tree, 0); + __test_case_3(em_tree, SZ_8K); + __test_case_3(em_tree, (12 * 1024ULL)); +} + int btrfs_test_extent_map() { struct extent_map_tree *em_tree; @@ -197,6 +270,7 @@ int btrfs_test_extent_map() test_case_1(em_tree); test_case_2(em_tree); + test_case_3(em_tree); kfree(em_tree); return 0; |