Re: [PATCH v2 2/8] ext4: kunit tests for higher level extent manipulation functions

[Zhang Yi <yizhang089@gmail.com>]

On 1/14/2026 10:57 PM, Ojaswin Mujoo wrote:
> Add more kunit tests to cover the high level caller
> ext4_map_create_blocks(). We pass flags in a manner that covers
> the below function:
> 
> 1. ext4_ext_handle_unwritten_extents()
>    1.1 - Split/Convert unwritten extent to written in endio convtext.
>    1.2 - Split/Convert unwritten extent to written in non endio context.
>    1.3 - Zeroout tests for the above 2 cases
> 2. convert_initialized_extent() - Convert written extent to unwritten
>     during zero range
> 
> Signed-off-by: Ojaswin Mujoo <ojaswin@linux.ibm.com>


It looks good to me.

Reviewed-by: Zhang Yi <yi.zhang@huawei.com>

> ---
>   fs/ext4/ext4.h           |   4 +
>   fs/ext4/extents-test.c   | 287 ++++++++++++++++++++++++++++++++++++++-
>   fs/ext4/extents_status.c |   3 +
>   fs/ext4/inode.c          |   8 +-
>   4 files changed, 295 insertions(+), 7 deletions(-)
> 
> diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
> index 174c51402864..5f744bd19dea 100644
> --- a/fs/ext4/ext4.h
> +++ b/fs/ext4/ext4.h
> @@ -3786,6 +3786,10 @@ extern int ext4_convert_unwritten_io_end_vec(handle_t *handle,
>   					     ext4_io_end_t *io_end);
>   extern int ext4_map_blocks(handle_t *handle, struct inode *inode,
>   			   struct ext4_map_blocks *map, int flags);
> +extern int ext4_map_query_blocks(handle_t *handle, struct inode *inode,
> +				  struct ext4_map_blocks *map, int flags);
> +extern int ext4_map_create_blocks(handle_t *handle, struct inode *inode,
> +				  struct ext4_map_blocks *map, int flags);
>   extern int ext4_ext_calc_credits_for_single_extent(struct inode *inode,
>   						   int num,
>   						   struct ext4_ext_path *path);
> diff --git a/fs/ext4/extents-test.c b/fs/ext4/extents-test.c
> index 02565ad19abe..ebd7af64315a 100644
> --- a/fs/ext4/extents-test.c
> +++ b/fs/ext4/extents-test.c
> @@ -77,10 +77,18 @@ struct kunit_ext_data_state {
>   	ext4_lblk_t len_blk;
>   };
>   
> +enum kunit_test_types {
> +	TEST_SPLIT_CONVERT,
> +	TEST_CREATE_BLOCKS,
> +};
> +
>   struct kunit_ext_test_param {
>   	/* description of test */
>   	char *desc;
>   
> +	/* determines which function will be tested */
> +	int type;
> +
>   	/* is extent unwrit at beginning of test */
>   	bool is_unwrit_at_start;
>   
> @@ -90,6 +98,9 @@ struct kunit_ext_test_param {
>   	/* map describing range to split */
>   	struct ext4_map_blocks split_map;
>   
> +	/* disable zeroout */
> +	bool disable_zeroout;
> +
>   	/* no of extents expected after split */
>   	int nr_exp_ext;
>   
> @@ -131,6 +142,9 @@ static struct file_system_type ext_fs_type = {
>   
>   static void extents_kunit_exit(struct kunit *test)
>   {
> +	struct ext4_sb_info *sbi = k_ctx.k_ei->vfs_inode.i_sb->s_fs_info;
> +
> +	kfree(sbi);
>   	kfree(k_ctx.k_ei);
>   	kfree(k_ctx.k_data);
>   }
> @@ -162,6 +176,13 @@ static void ext4_es_remove_extent_stub(struct inode *inode, ext4_lblk_t lblk,
>   	return;
>   }
>   
> +void ext4_es_insert_extent_stub(struct inode *inode, ext4_lblk_t lblk,
> +				ext4_lblk_t len, ext4_fsblk_t pblk,
> +				unsigned int status, bool delalloc_reserve_used)
> +{
> +	return;
> +}
> +
>   static void ext4_zeroout_es_stub(struct inode *inode, struct ext4_extent *ex)
>   {
>   	return;
> @@ -220,6 +241,7 @@ static int extents_kunit_init(struct kunit *test)
>   	struct ext4_inode_info *ei;
>   	struct inode *inode;
>   	struct super_block *sb;
> +	struct ext4_sb_info *sbi = NULL;
>   	struct kunit_ext_test_param *param =
>   		(struct kunit_ext_test_param *)(test->param_value);
>   
> @@ -237,7 +259,20 @@ static int extents_kunit_init(struct kunit *test)
>   	sb->s_blocksize = 4096;
>   	sb->s_blocksize_bits = 12;
>   
> -	ei->i_disksize = (EX_DATA_LBLK + EX_DATA_LEN + 10) << sb->s_blocksize_bits;
> +	sbi = kzalloc(sizeof(struct ext4_sb_info), GFP_KERNEL);
> +	if (sbi == NULL)
> +		return -ENOMEM;
> +
> +	sbi->s_sb = sb;
> +	sb->s_fs_info = sbi;
> +
> +	if (!param || !param->disable_zeroout)
> +		sbi->s_extent_max_zeroout_kb = 32;
> +
> +	ei->i_disksize = (EX_DATA_LBLK + EX_DATA_LEN + 10)
> +			 << sb->s_blocksize_bits;
> +	ei->i_flags = 0;
> +	ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
>   	inode->i_sb = sb;
>   
>   	k_ctx.k_data = kzalloc(EX_DATA_LEN * 4096, GFP_KERNEL);
> @@ -277,6 +312,8 @@ static int extents_kunit_init(struct kunit *test)
>   				   __ext4_ext_dirty_stub);
>   	kunit_activate_static_stub(test, ext4_es_remove_extent,
>   				   ext4_es_remove_extent_stub);
> +	kunit_activate_static_stub(test, ext4_es_insert_extent,
> +				   ext4_es_insert_extent_stub);
>   	kunit_activate_static_stub(test, ext4_zeroout_es, ext4_zeroout_es_stub);
>   	kunit_activate_static_stub(test, ext4_ext_zeroout, ext4_ext_zeroout_stub);
>   	kunit_activate_static_stub(test, ext4_issue_zeroout,
> @@ -301,6 +338,30 @@ static int check_buffer(char *buf, int c, int size)
>   	return 1;
>   }
>   
> +/*
> + * Simulate a map block call by first calling ext4_map_query_blocks() to
> + * correctly populate map flags and pblk and then call the
> + * ext4_map_create_blocks() to do actual split and conversion. This is easier
> + * than calling ext4_map_blocks() because that needs mocking a lot of unrelated
> + * functions.
> + */
> +static void ext4_map_create_blocks_helper(struct kunit *test,
> +					  struct inode *inode,
> +					  struct ext4_map_blocks *map,
> +					  int flags)
> +{
> +	int retval = 0;
> +
> +	retval = ext4_map_query_blocks(NULL, inode, map, flags);
> +	if (retval < 0) {
> +		KUNIT_FAIL(test,
> +			   "ext4_map_query_blocks() failed. Cannot proceed\n");
> +		return;
> +	}
> +
> +	ext4_map_create_blocks(NULL, inode, map, flags);
> +}
> +
>   static void test_split_convert(struct kunit *test)
>   {
>   	struct ext4_ext_path *path;
> @@ -330,8 +391,18 @@ static void test_split_convert(struct kunit *test)
>   
>   	map.m_lblk = param->split_map.m_lblk;
>   	map.m_len = param->split_map.m_len;
> -	ext4_split_convert_extents(NULL, inode, &map, path,
> -				   param->split_flags, NULL);
> +
> +	switch (param->type) {
> +	case TEST_SPLIT_CONVERT:
> +		path = ext4_split_convert_extents(NULL, inode, &map, path,
> +						  param->split_flags, NULL);
> +		break;
> +	case TEST_CREATE_BLOCKS:
> +		ext4_map_create_blocks_helper(test, inode, &map, param->split_flags);
> +		break;
> +	default:
> +		KUNIT_FAIL(test, "param->type %d not support.", param->type);
> +	}
>   
>   	path = ext4_find_extent(inode, EX_DATA_LBLK, NULL, 0);
>   	ex = path->p_ext;
> @@ -383,6 +454,7 @@ static void test_split_convert(struct kunit *test)
>   static const struct kunit_ext_test_param test_split_convert_params[] = {
>   	/* unwrit to writ splits */
>   	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ",
> +	  .type = TEST_SPLIT_CONVERT,
>   	  .is_unwrit_at_start = 1,
>   	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
>   	  .split_map = { .m_lblk = 10, .m_len = 1 },
> @@ -391,6 +463,7 @@ static const struct kunit_ext_test_param test_split_convert_params[] = {
>   			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 1 } },
>   	  .is_zeroout_test = 0 },
>   	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ",
> +	  .type = TEST_SPLIT_CONVERT,
>   	  .is_unwrit_at_start = 1,
>   	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
>   	  .split_map = { .m_lblk = 11, .m_len = 2 },
> @@ -399,6 +472,7 @@ static const struct kunit_ext_test_param test_split_convert_params[] = {
>   			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 0 } },
>   	  .is_zeroout_test = 0 },
>   	{ .desc = "split unwrit extent to 3 extents and convert 2nd half to writ",
> +	  .type = TEST_SPLIT_CONVERT,
>   	  .is_unwrit_at_start = 1,
>   	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
>   	  .split_map = { .m_lblk = 11, .m_len = 1 },
> @@ -410,6 +484,7 @@ static const struct kunit_ext_test_param test_split_convert_params[] = {
>   
>   	/* writ to unwrit splits */
>   	{ .desc = "split writ extent to 2 extents and convert 1st half unwrit",
> +	  .type = TEST_SPLIT_CONVERT,
>   	  .is_unwrit_at_start = 0,
>   	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
>   	  .split_map = { .m_lblk = 10, .m_len = 1 },
> @@ -418,6 +493,7 @@ static const struct kunit_ext_test_param test_split_convert_params[] = {
>   			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 0 } },
>   	  .is_zeroout_test = 0 },
>   	{ .desc = "split writ extent to 2 extents and convert 2nd half unwrit",
> +	  .type = TEST_SPLIT_CONVERT,
>   	  .is_unwrit_at_start = 0,
>   	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
>   	  .split_map = { .m_lblk = 11, .m_len = 2 },
> @@ -426,6 +502,7 @@ static const struct kunit_ext_test_param test_split_convert_params[] = {
>   			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 1 } },
>   	  .is_zeroout_test = 0 },
>   	{ .desc = "split writ extent to 3 extents and convert 2nd half to unwrit",
> +	  .type = TEST_SPLIT_CONVERT,
>   	  .is_unwrit_at_start = 0,
>   	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
>   	  .split_map = { .m_lblk = 11, .m_len = 1 },
> @@ -440,6 +517,7 @@ static const struct kunit_ext_test_param test_split_convert_params[] = {
>   	 */
>   	/* unwrit to writ splits */
>   	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (zeroout)",
> +	  .type = TEST_SPLIT_CONVERT,
>   	  .is_unwrit_at_start = 1,
>   	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
>   	  .split_map = { .m_lblk = 10, .m_len = 1 },
> @@ -451,6 +529,7 @@ static const struct kunit_ext_test_param test_split_convert_params[] = {
>   	  .exp_data_state = { { .exp_char = 'X', .off_blk = 0, .len_blk = 1 },
>   			      { .exp_char = 0, .off_blk = 1, .len_blk = 2 } } },
>   	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (zeroout)",
> +	  .type = TEST_SPLIT_CONVERT,
>   	  .is_unwrit_at_start = 1,
>   	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
>   	  .split_map = { .m_lblk = 11, .m_len = 2 },
> @@ -462,6 +541,7 @@ static const struct kunit_ext_test_param test_split_convert_params[] = {
>   	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
>   			      { .exp_char = 'X', .off_blk = 1, .len_blk = 2 } } },
>   	{ .desc = "split unwrit extent to 3 extents and convert 2nd half writ (zeroout)",
> +	  .type = TEST_SPLIT_CONVERT,
>   	  .is_unwrit_at_start = 1,
>   	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
>   	  .split_map = { .m_lblk = 11, .m_len = 1 },
> @@ -476,6 +556,185 @@ static const struct kunit_ext_test_param test_split_convert_params[] = {
>   
>   };
>   
> +static const struct kunit_ext_test_param test_convert_initialized_params[] = {
> +	/* writ to unwrit splits */
> +	{ .desc = "split writ extent to 2 extents and convert 1st half unwrit",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
> +	  .is_unwrit_at_start = 0,
> +	  .split_map = { .m_lblk = 10, .m_len = 1 },
> +	  .nr_exp_ext = 2,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 1, .is_unwrit = 1 },
> +			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 0 },
> +	{ .desc = "split writ extent to 2 extents and convert 2nd half unwrit",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
> +	  .is_unwrit_at_start = 0,
> +	  .split_map = { .m_lblk = 11, .m_len = 2 },
> +	  .nr_exp_ext = 2,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 1, .is_unwrit = 0 },
> +			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 1 } },
> +	  .is_zeroout_test = 0 },
> +	{ .desc = "split writ extent to 3 extents and convert 2nd half to unwrit",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
> +	  .is_unwrit_at_start = 0,
> +	  .split_map = { .m_lblk = 11, .m_len = 1 },
> +	  .nr_exp_ext = 3,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 1, .is_unwrit = 0 },
> +			     { .ex_lblk = 11, .ex_len = 1, .is_unwrit = 1 },
> +			     { .ex_lblk = 12, .ex_len = 1, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 0 },
> +};
> +
> +static const struct kunit_ext_test_param test_handle_unwritten_params[] = {
> +	/* unwrit to writ splits via endio path */
> +	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (endio)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
> +	  .split_map = { .m_lblk = 10, .m_len = 1 },
> +	  .nr_exp_ext = 2,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 1, .is_unwrit = 0 },
> +			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 1 } },
> +	  .is_zeroout_test = 0 },
> +	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (endio)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
> +	  .split_map = { .m_lblk = 11, .m_len = 2 },
> +	  .nr_exp_ext = 2,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 1, .is_unwrit = 1 },
> +			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 0 },
> +	{ .desc = "split unwrit extent to 3 extents and convert 2nd half to writ (endio)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
> +	  .split_map = { .m_lblk = 11, .m_len = 1 },
> +	  .nr_exp_ext = 3,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 1, .is_unwrit = 1 },
> +			     { .ex_lblk = 11, .ex_len = 1, .is_unwrit = 0 },
> +			     { .ex_lblk = 12, .ex_len = 1, .is_unwrit = 1 } },
> +	  .is_zeroout_test = 0 },
> +
> +	/* unwrit to writ splits via non-endio path */
> +	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (non endio)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CREATE,
> +	  .split_map = { .m_lblk = 10, .m_len = 1 },
> +	  .nr_exp_ext = 2,
> +	  .disable_zeroout = true,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 1, .is_unwrit = 0 },
> +			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 1 } },
> +	  .is_zeroout_test = 0 },
> +	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (non endio)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CREATE,
> +	  .split_map = { .m_lblk = 11, .m_len = 2 },
> +	  .nr_exp_ext = 2,
> +	  .disable_zeroout = true,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 1, .is_unwrit = 1 },
> +			     { .ex_lblk = 11, .ex_len = 2, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 0 },
> +	{ .desc = "split unwrit extent to 3 extents and convert 2nd half to writ (non endio)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CREATE,
> +	  .split_map = { .m_lblk = 11, .m_len = 1 },
> +	  .nr_exp_ext = 3,
> +	  .disable_zeroout = true,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 1, .is_unwrit = 1 },
> +			     { .ex_lblk = 11, .ex_len = 1, .is_unwrit = 0 },
> +			     { .ex_lblk = 12, .ex_len = 1, .is_unwrit = 1 } },
> +	  .is_zeroout_test = 0 },
> +
> +	/*
> +	 * ***** zeroout tests *****
> +	 */
> +	/* unwrit to writ splits (endio)*/
> +	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (endio, zeroout)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
> +	  .split_map = { .m_lblk = 10, .m_len = 1 },
> +	  .nr_exp_ext = 1,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 3, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 1,
> +	  .nr_exp_data_segs = 2,
> +	  /* 1 block of data followed by 2 blocks of zeroes */
> +	  .exp_data_state = { { .exp_char = 'X', .off_blk = 0, .len_blk = 1 },
> +			      { .exp_char = 0, .off_blk = 1, .len_blk = 2 } } },
> +	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (endio, zeroout)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
> +	  .split_map = { .m_lblk = 11, .m_len = 2 },
> +	  .nr_exp_ext = 1,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 3, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 1,
> +	  .nr_exp_data_segs = 2,
> +	  /* 1 block of zeroes followed by 2 blocks of data */
> +	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
> +			      { .exp_char = 'X', .off_blk = 1, .len_blk = 2 } } },
> +	{ .desc = "split unwrit extent to 3 extents and convert 2nd half writ (endio, zeroout)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
> +	  .split_map = { .m_lblk = 11, .m_len = 1 },
> +	  .nr_exp_ext = 1,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 3, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 1,
> +	  .nr_exp_data_segs = 3,
> +	  /* [zeroes] [data] [zeroes] */
> +	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
> +			      { .exp_char = 'X', .off_blk = 1, .len_blk = 1 },
> +			      { .exp_char = 0, .off_blk = 2, .len_blk = 1 } } },
> +
> +	/* unwrit to writ splits (non-endio)*/
> +	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (non-endio, zeroout)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CREATE,
> +	  .split_map = { .m_lblk = 10, .m_len = 1 },
> +	  .nr_exp_ext = 1,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 3, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 1,
> +	  .nr_exp_data_segs = 2,
> +	  /* 1 block of data followed by 2 blocks of zeroes */
> +	  .exp_data_state = { { .exp_char = 'X', .off_blk = 0, .len_blk = 1 },
> +			      { .exp_char = 0, .off_blk = 1, .len_blk = 2 } } },
> +	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (non-endio, zeroout)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CREATE,
> +	  .split_map = { .m_lblk = 11, .m_len = 2 },
> +	  .nr_exp_ext = 1,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 3, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 1,
> +	  .nr_exp_data_segs = 2,
> +	  /* 1 block of zeroes followed by 2 blocks of data */
> +	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
> +			      { .exp_char = 'X', .off_blk = 1, .len_blk = 2 } } },
> +	{ .desc = "split unwrit extent to 3 extents and convert 2nd half writ (non-endio, zeroout)",
> +	  .type = TEST_CREATE_BLOCKS,
> +	  .is_unwrit_at_start = 1,
> +	  .split_flags = EXT4_GET_BLOCKS_CREATE,
> +	  .split_map = { .m_lblk = 11, .m_len = 1 },
> +	  .nr_exp_ext = 1,
> +	  .exp_ext_state = { { .ex_lblk = 10, .ex_len = 3, .is_unwrit = 0 } },
> +	  .is_zeroout_test = 1,
> +	  .nr_exp_data_segs = 3,
> +	  /* [zeroes] [data] [zeroes] */
> +	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
> +			      { .exp_char = 'X', .off_blk = 1, .len_blk = 1 },
> +			      { .exp_char = 0, .off_blk = 2, .len_blk = 1 } } },
> +
> +};
> +
>   static void ext_get_desc(struct kunit *test, const void *p, char *desc)
>   
>   {
> @@ -493,6 +752,24 @@ static int test_split_convert_param_init(struct kunit *test)
>   	return 0;
>   }
>   
> +static int test_convert_initialized_param_init(struct kunit *test)
> +{
> +	size_t arr_size = ARRAY_SIZE(test_convert_initialized_params);
> +
> +	kunit_register_params_array(test, test_convert_initialized_params,
> +				    arr_size, ext_get_desc);
> +	return 0;
> +}
> +
> +static int test_handle_unwritten_init(struct kunit *test)
> +{
> +	size_t arr_size = ARRAY_SIZE(test_handle_unwritten_params);
> +
> +	kunit_register_params_array(test, test_handle_unwritten_params,
> +				    arr_size, ext_get_desc);
> +	return 0;
> +}
> +
>   /*
>    * Note that we use KUNIT_CASE_PARAM_WITH_INIT() instead of the more compact
>    * KUNIT_ARRAY_PARAM() because the later currently has a limitation causing the
> @@ -503,6 +780,10 @@ static int test_split_convert_param_init(struct kunit *test)
>   static struct kunit_case extents_test_cases[] = {
>   	KUNIT_CASE_PARAM_WITH_INIT(test_split_convert, kunit_array_gen_params,
>   				   test_split_convert_param_init, NULL),
> +	KUNIT_CASE_PARAM_WITH_INIT(test_split_convert, kunit_array_gen_params,
> +				   test_convert_initialized_param_init, NULL),
> +	KUNIT_CASE_PARAM_WITH_INIT(test_split_convert, kunit_array_gen_params,
> +				   test_handle_unwritten_init, NULL),
>   	{}
>   };
>   
> diff --git a/fs/ext4/extents_status.c b/fs/ext4/extents_status.c
> index 6c1faf7c9f2a..095ccb7ba4ba 100644
> --- a/fs/ext4/extents_status.c
> +++ b/fs/ext4/extents_status.c
> @@ -916,6 +916,9 @@ void ext4_es_insert_extent(struct inode *inode, ext4_lblk_t lblk,
>   	struct pending_reservation *pr = NULL;
>   	bool revise_pending = false;
>   
> +	KUNIT_STATIC_STUB_REDIRECT(ext4_es_insert_extent, inode, lblk, len,
> +				   pblk, status, delalloc_reserve_used);
> +
>   	if (EXT4_SB(inode->i_sb)->s_mount_state & EXT4_FC_REPLAY)
>   		return;
>   
> diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
> index c60813260f9a..8a6ad16e7417 100644
> --- a/fs/ext4/inode.c
> +++ b/fs/ext4/inode.c
> @@ -542,8 +542,8 @@ static int ext4_map_query_blocks_next_in_leaf(handle_t *handle,
>   	return map->m_len;
>   }
>   
> -static int ext4_map_query_blocks(handle_t *handle, struct inode *inode,
> -				 struct ext4_map_blocks *map, int flags)
> +int ext4_map_query_blocks(handle_t *handle, struct inode *inode,
> +			  struct ext4_map_blocks *map, int flags)
>   {
>   	unsigned int status;
>   	int retval;
> @@ -589,8 +589,8 @@ static int ext4_map_query_blocks(handle_t *handle, struct inode *inode,
>   	return retval;
>   }
>   
> -static int ext4_map_create_blocks(handle_t *handle, struct inode *inode,
> -				  struct ext4_map_blocks *map, int flags)
> +int ext4_map_create_blocks(handle_t *handle, struct inode *inode,
> +			   struct ext4_map_blocks *map, int flags)
>   {
>   	unsigned int status;
>   	int err, retval = 0;