Re: [PATCH v2] btrfs: Add self-tests for btrfs_rmap_block

[David Sterba <dsterba@suse.cz>]

On Tue, Dec 10, 2019 at 08:00:45PM +0200, Nikolay Borisov wrote:
> This is enough to exercise out of boundary address exclusion as well as
> address matching.
> 
> Signed-off-by: Nikolay Borisov <nborisov@suse.com>
> ---
> V2:
>  * Adjusted comments about some members of struct rmap_test_vector
>  * Fixed inline comments
>  * Correctly handle error when initialising dummy device
>  * Other minor cosmetic changes around comments/braces for single statement 'if'
>  and structure initialization

I still found issues unfixed from v1 and some that I did not notice
before

>  fs/btrfs/tests/extent-map-tests.c | 146 +++++++++++++++++++++++++++++-
>  1 file changed, 145 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/btrfs/tests/extent-map-tests.c b/fs/btrfs/tests/extent-map-tests.c
> index 4a7f796c9900..4878904434af 100644
> --- a/fs/btrfs/tests/extent-map-tests.c
> +++ b/fs/btrfs/tests/extent-map-tests.c
> @@ -6,6 +6,10 @@
>  #include <linux/types.h>
>  #include "btrfs-tests.h"
>  #include "../ctree.h"
> +#include "../volumes.h"
> +#include "../disk-io.h"
> +#include "../block-group.h"
> +

Extra newline

> 
>  static void free_extent_map_tree(struct extent_map_tree *em_tree)
>  {
> @@ -437,11 +441,144 @@ static int test_case_4(struct btrfs_fs_info *fs_info,
>  	return ret;
>  }
> 
> +struct rmap_test_vector {
> +	u64 raid_type;
> +	u64 physical_start;
> +	u64 data_stripe_size;
> +	u64 num_data_stripes;
> +	u64 num_stripes;
> +	/* Assume we won't have more than 5 physical stripes */
> +	u64 data_stripe_phys_start[5];
> +	int expected_mapped_addr;

This should be bool

> +	/* Physical to logical addresses */
> +	u64 mapped_logical[5];
> +};
> +
> +static int test_rmap_block(struct btrfs_fs_info *fs_info,
> +			   struct rmap_test_vector *test)
> +{
> +	struct extent_map *em;
> +	struct map_lookup *map = NULL;
> +	u64 *logical;
> +	int i, out_ndaddrs, out_stripe_len;
> +	int ret = -EINVAL;
> +
> +	em = alloc_extent_map();
> +	if (!em) {
> +		test_std_err(TEST_ALLOC_EXTENT_MAP);
> +		return -ENOMEM;
> +	}
> +
> +	map = kmalloc(map_lookup_size(test->num_stripes), GFP_KERNEL);
> +	if (!map) {
> +		kfree(em);
> +		test_std_err(TEST_ALLOC_EXTENT_MAP);
> +		return -ENOMEM;
> +	}
> +
> +	set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
> +	/* Start at 4gb logical address */
> +	em->start = SZ_4G;
> +	em->len = test->data_stripe_size * test->num_data_stripes;
> +	em->block_len = em->len;
> +	em->orig_block_len = test->data_stripe_size;
> +	em->map_lookup = map;
> +
> +	map->num_stripes = test->num_stripes;
> +	map->stripe_len = BTRFS_STRIPE_LEN;
> +	map->type = test->raid_type;
> +
> +	for (i = 0; i < map->num_stripes; i++)
> +	{
> +		struct btrfs_device *dev = btrfs_alloc_dummy_device(fs_info);
> +		if (!dev) {
> +			test_err("ENOMEM while allocating dummy device");

			ret = -ENOMEM;

And the error message should follow the scheme of the other standard
error messages (defined in test_error)

> +			goto out;
> +		}
> +		map->stripes[i].dev = dev;
> +		map->stripes[i].physical = test->data_stripe_phys_start[i];
> +	}
> +
> +	write_lock(&fs_info->mapping_tree.lock);
> +	ret = add_extent_mapping(&fs_info->mapping_tree, em, 0);
> +	write_unlock(&fs_info->mapping_tree.lock);
> +	if (ret)
> +		test_err("Error adding block group mapping to mapping tree");

Error found but no exit, other selftests do that. And no capital letter
at the beginning of the string. I've added a label before the 2nd
free_extent_map.

> +
> +	ret = btrfs_rmap_block(fs_info, em->start, btrfs_sb_offset(1),
> +			       &logical, &out_ndaddrs, &out_stripe_len);
> +	if (ret || (out_ndaddrs == 0 && test->expected_mapped_addr)) {
> +		test_err("Didn't rmap anything but expected %d",

... in all strings passed to test_err

> +			 test->expected_mapped_addr);
> +		goto out;
> +	}
> +
> +	if (out_stripe_len != BTRFS_STRIPE_LEN) {
> +		test_err("Calculated stripe len doesn't match");

Here

> +		goto out;
> +	}
> +
> +	if (out_ndaddrs != test->expected_mapped_addr) {
> +		for (i = 0; i < out_ndaddrs; i++)
> +			test_msg("Mapped %llu", logical[i]);

Here

> +		test_err("Unexpected number of mapped addresses: %d", out_ndaddrs);

Here
> +		goto out;
> +	}
> +
> +	for (i = 0; i < out_ndaddrs; i++) {
> +		if (logical[i] != test->mapped_logical[i]) {
> +			test_err("Unexpected logical address mapped");

Here

> +			goto out;
> +		}
> +	}
> +
> +	ret = 0;
> +out:
> +	write_lock(&fs_info->mapping_tree.lock);
> +	remove_extent_mapping(&fs_info->mapping_tree, em);
> +	write_unlock(&fs_info->mapping_tree.lock);
> +	/* For us */
> +	free_extent_map(em);
> +	/* For the tree */
> +	free_extent_map(em);
> +	return ret;
> +}
> +
>  int btrfs_test_extent_map(void)
>  {
>  	struct btrfs_fs_info *fs_info = NULL;
>  	struct extent_map_tree *em_tree;
> -	int ret = 0;
> +	int ret = 0, i;
> +	struct rmap_test_vector rmap_tests[] = {
> +		{
> +			/*
> +			 * Tests a chunk with 2 data stripes one of which
> +			 * interesects the physical address of the super block
> +			 * is correctly recognised.
> +			 */
> +			.raid_type = BTRFS_BLOCK_GROUP_RAID1,
> +			.physical_start = SZ_64M - SZ_4M,
> +			.data_stripe_size = SZ_256M,
> +			.num_data_stripes = 2,
> +			.num_stripes = 2,
> +			.data_stripe_phys_start = {SZ_64M - SZ_4M, SZ_64M - SZ_4M + SZ_256M},

Formatting

> +			.expected_mapped_addr = 1,
> +			.mapped_logical= {SZ_4G + SZ_4M}
> +		},
> +		{
> +			/* test that out of range physical addresses are ignored */
> +
> +			 /* SINGLE chunk type */
> +			.raid_type = 0,
> +			.physical_start = SZ_4G,
> +			.data_stripe_size = SZ_256M,
> +			.num_data_stripes = 1,
> +			.num_stripes = 1,
> +			.data_stripe_phys_start = {SZ_256M},
> +			.expected_mapped_addr = 0,
> +			.mapped_logical = {0}
> +		}
> +	};
> 
>  	test_msg("running extent_map tests");
> 
> @@ -474,6 +611,13 @@ int btrfs_test_extent_map(void)
>  		goto out;
>  	ret = test_case_4(fs_info, em_tree);
> 
> +	test_msg("Running rmap tests.");

	test_msg("running rmap tests");

> +	for (i = 0; i < ARRAY_SIZE(rmap_tests); i++) {
> +		ret = test_rmap_block(fs_info, &rmap_tests[i]);
> +		if (ret)
> +			goto out;
> +	}
> +
>  out:
>  	kfree(em_tree);
>  	btrfs_free_dummy_fs_info(fs_info);
> --
> 2.17.1