xref: /linux/fs/ext4/extents-test.c (revision 4dff18488fe22b743d6e2ee32ca4a533ea237454)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Written by Ojaswin Mujoo <ojaswin@linux.ibm.com> (IBM)
4  *
5  * These Kunit tests are designed to test the functionality of
6  * extent split and conversion in ext4.
7  *
8  * Currently, ext4 can split extents in 2 ways:
9  * 1. By splitting the extents in the extent tree and optionally converting them
10  *    to written or unwritten based on flags passed.
11  * 2. In case 1 encounters an error, ext4 instead zerooes out the unwritten
12  *    areas of the extent and marks the complete extent written.
13  *
14  * The primary function that handles this is ext4_split_convert_extents().
15  *
16  * We test both of the methods of split. The behavior we try to enforce is:
17  * 1. When passing EXT4_GET_BLOCKS_CONVERT flag to ext4_split_convert_extents(),
18  *    the split extent should be converted to initialized.
19  * 2. When passing EXT4_GET_BLOCKS_CONVERT_UNWRITTEN flag to
20  *    ext4_split_convert_extents(), the split extent should be converted to
21  *    uninitialized.
22  * 3. In case we use the zeroout method, then we should correctly write zeroes
23  *    to the unwritten areas of the extent and we should not corrupt/leak any
24  *    data.
25  *
26  * Enforcing 1 and 2 is straight forward, we just setup a minimal inode with
27  * extent tree, call ext4_split_convert_extents() and check the final state of
28  * the extent tree.
29  *
30  * For zeroout testing, we maintain a separate buffer which represents the disk
31  * data corresponding to the extents. We then override ext4's zeroout functions
32  * to instead write zeroes to our buffer. Then, we override
33  * ext4_ext_insert_extent() to return -ENOSPC, which triggers the zeroout.
34  * Finally, we check the state of the extent tree and zeroout buffer to confirm
35  * everything went well.
36  */
37 
38 #include <kunit/test.h>
39 #include <kunit/static_stub.h>
40 #include <linux/gfp_types.h>
41 #include <linux/stddef.h>
42 
43 #include "ext4.h"
44 #include "ext4_extents.h"
45 
46 #define EXT_DATA_PBLK 100
47 #define EXT_DATA_LBLK 10
48 #define EXT_DATA_LEN 3
49 
50 struct kunit_ctx {
51 	/*
52 	 * Ext4 inode which has only 1 unwrit extent
53 	 */
54 	struct ext4_inode_info *k_ei;
55 	/*
56 	 * Represents the underlying data area (used for zeroout testing)
57 	 */
58 	char *k_data;
59 } k_ctx;
60 
61 /*
62  * describes the state of an expected extent in extent tree.
63  */
64 struct kunit_ext_state {
65 	ext4_lblk_t ex_lblk;
66 	ext4_lblk_t ex_len;
67 	bool is_unwrit;
68 };
69 
70 /*
71  * describes the state of the data area of a writ extent. Used for testing
72  * correctness of zeroout.
73  */
74 struct kunit_ext_data_state {
75 	char exp_char;
76 	ext4_lblk_t off_blk;
77 	ext4_lblk_t len_blk;
78 };
79 
80 enum kunit_test_types {
81 	TEST_SPLIT_CONVERT,
82 	TEST_CREATE_BLOCKS,
83 };
84 
85 struct kunit_ext_test_param {
86 	/* description of test */
87 	char *desc;
88 
89 	/* determines which function will be tested */
90 	int type;
91 
92 	/* is extent unwrit at beginning of test */
93 	bool is_unwrit_at_start;
94 
95 	/* flags to pass while splitting */
96 	int split_flags;
97 
98 	/* map describing range to split */
99 	struct ext4_map_blocks split_map;
100 
101 	/* disable zeroout */
102 	bool disable_zeroout;
103 
104 	/* no of extents expected after split */
105 	int nr_exp_ext;
106 
107 	/*
108 	 * expected state of extents after split. We will never split into more
109 	 * than 3 extents
110 	 */
111 	struct kunit_ext_state exp_ext_state[3];
112 
113 	/* Below fields used for zeroout tests */
114 
115 	bool is_zeroout_test;
116 	/*
117 	 * no of expected data segments (zeroout tests). Example, if we expect
118 	 * data to be 4kb 0s, followed by 8kb non-zero, then nr_exp_data_segs==2
119 	 */
120 	int nr_exp_data_segs;
121 
122 	/*
123 	 * expected state of data area after zeroout.
124 	 */
125 	struct kunit_ext_data_state exp_data_state[3];
126 };
127 
128 static void ext_kill_sb(struct super_block *sb)
129 {
130 	generic_shutdown_super(sb);
131 }
132 
133 static int ext_set(struct super_block *sb, void *data)
134 {
135 	return 0;
136 }
137 
138 static struct file_system_type ext_fs_type = {
139 	.name = "extents test",
140 	.kill_sb = ext_kill_sb,
141 };
142 
143 static void extents_kunit_exit(struct kunit *test)
144 {
145 	struct ext4_sb_info *sbi = k_ctx.k_ei->vfs_inode.i_sb->s_fs_info;
146 
147 	kfree(sbi);
148 	kfree(k_ctx.k_ei);
149 	kfree(k_ctx.k_data);
150 }
151 
152 static void ext4_cache_extents_stub(struct inode *inode,
153 				    struct ext4_extent_header *eh)
154 {
155 	return;
156 }
157 
158 static int __ext4_ext_dirty_stub(const char *where, unsigned int line,
159 				 handle_t *handle, struct inode *inode,
160 				 struct ext4_ext_path *path)
161 {
162 	return 0;
163 }
164 
165 static struct ext4_ext_path *
166 ext4_ext_insert_extent_stub(handle_t *handle, struct inode *inode,
167 			    struct ext4_ext_path *path,
168 			    struct ext4_extent *newext, int gb_flags)
169 {
170 	return ERR_PTR(-ENOSPC);
171 }
172 
173 static void ext4_es_remove_extent_stub(struct inode *inode, ext4_lblk_t lblk,
174 				       ext4_lblk_t len)
175 {
176 	return;
177 }
178 
179 void ext4_es_insert_extent_stub(struct inode *inode, ext4_lblk_t lblk,
180 				ext4_lblk_t len, ext4_fsblk_t pblk,
181 				unsigned int status, bool delalloc_reserve_used)
182 {
183 	return;
184 }
185 
186 static void ext4_zeroout_es_stub(struct inode *inode, struct ext4_extent *ex)
187 {
188 	return;
189 }
190 
191 /*
192  * We will zeroout the equivalent range in the data area
193  */
194 static int ext4_ext_zeroout_stub(struct inode *inode, struct ext4_extent *ex)
195 {
196 	ext4_lblk_t ee_block, off_blk;
197 	loff_t ee_len;
198 	loff_t off_bytes;
199 	struct kunit *test = kunit_get_current_test();
200 
201 	ee_block = le32_to_cpu(ex->ee_block);
202 	ee_len = ext4_ext_get_actual_len(ex);
203 
204 	KUNIT_EXPECT_EQ_MSG(test, 1, ee_block >= EXT_DATA_LBLK, "ee_block=%d",
205 			    ee_block);
206 	KUNIT_EXPECT_EQ(test, 1,
207 			ee_block + ee_len <= EXT_DATA_LBLK + EXT_DATA_LEN);
208 
209 	off_blk = ee_block - EXT_DATA_LBLK;
210 	off_bytes = off_blk << inode->i_sb->s_blocksize_bits;
211 	memset(k_ctx.k_data + off_bytes, 0,
212 	       ee_len << inode->i_sb->s_blocksize_bits);
213 
214 	return 0;
215 }
216 
217 static int ext4_issue_zeroout_stub(struct inode *inode, ext4_lblk_t lblk,
218 				   ext4_fsblk_t pblk, ext4_lblk_t len)
219 {
220 	ext4_lblk_t off_blk;
221 	loff_t off_bytes;
222 	struct kunit *test = kunit_get_current_test();
223 
224 	kunit_log(KERN_ALERT, test,
225 		  "%s: lblk=%u pblk=%llu len=%u", __func__, lblk, pblk, len);
226 	KUNIT_EXPECT_EQ(test, 1, lblk >= EXT_DATA_LBLK);
227 	KUNIT_EXPECT_EQ(test, 1, lblk + len <= EXT_DATA_LBLK + EXT_DATA_LEN);
228 	KUNIT_EXPECT_EQ(test, 1, lblk - EXT_DATA_LBLK == pblk - EXT_DATA_PBLK);
229 
230 	off_blk = lblk - EXT_DATA_LBLK;
231 	off_bytes = off_blk << inode->i_sb->s_blocksize_bits;
232 	memset(k_ctx.k_data + off_bytes, 0,
233 	       len << inode->i_sb->s_blocksize_bits);
234 
235 	return 0;
236 }
237 
238 static int extents_kunit_init(struct kunit *test)
239 {
240 	struct ext4_extent_header *eh = NULL;
241 	struct ext4_inode_info *ei;
242 	struct inode *inode;
243 	struct super_block *sb;
244 	struct ext4_sb_info *sbi = NULL;
245 	struct kunit_ext_test_param *param =
246 		(struct kunit_ext_test_param *)(test->param_value);
247 
248 	/* setup the mock inode */
249 	k_ctx.k_ei = kzalloc(sizeof(struct ext4_inode_info), GFP_KERNEL);
250 	if (k_ctx.k_ei == NULL)
251 		return -ENOMEM;
252 	ei = k_ctx.k_ei;
253 	inode = &ei->vfs_inode;
254 
255 	sb = sget(&ext_fs_type, NULL, ext_set, 0, NULL);
256 	if (IS_ERR(sb))
257 		return PTR_ERR(sb);
258 
259 	sb->s_blocksize = 4096;
260 	sb->s_blocksize_bits = 12;
261 
262 	sbi = kzalloc(sizeof(struct ext4_sb_info), GFP_KERNEL);
263 	if (sbi == NULL)
264 		return -ENOMEM;
265 
266 	sbi->s_sb = sb;
267 	sb->s_fs_info = sbi;
268 
269 	if (!param || !param->disable_zeroout)
270 		sbi->s_extent_max_zeroout_kb = 32;
271 
272 	ei->i_disksize = (EXT_DATA_LBLK + EXT_DATA_LEN + 10)
273 			 << sb->s_blocksize_bits;
274 	ei->i_flags = 0;
275 	ext4_set_inode_flag(inode, EXT4_INODE_EXTENTS);
276 	inode->i_sb = sb;
277 
278 	k_ctx.k_data = kzalloc(EXT_DATA_LEN * 4096, GFP_KERNEL);
279 	if (k_ctx.k_data == NULL)
280 		return -ENOMEM;
281 
282 	/*
283 	 * set the data area to a junk value
284 	 */
285 	memset(k_ctx.k_data, 'X', EXT_DATA_LEN * 4096);
286 
287 	/* create a tree with depth 0 */
288 	eh = (struct ext4_extent_header *)k_ctx.k_ei->i_data;
289 
290 	/* Fill extent header */
291 	eh = ext_inode_hdr(&k_ctx.k_ei->vfs_inode);
292 	eh->eh_depth = 0;
293 	eh->eh_entries = cpu_to_le16(1);
294 	eh->eh_magic = EXT4_EXT_MAGIC;
295 	eh->eh_max =
296 		cpu_to_le16(ext4_ext_space_root_idx(&k_ctx.k_ei->vfs_inode, 0));
297 	eh->eh_generation = 0;
298 
299 	/*
300 	 * add 1 extent in leaf node covering:
301 	 * - lblks: [EXT_DATA_LBLK, EXT_DATA_LBLK * + EXT_DATA_LEN)
302 	 * - pblks: [EXT_DATA_PBLK, EXT_DATA_PBLK + EXT_DATA_LEN)
303 	 */
304 	EXT_FIRST_EXTENT(eh)->ee_block = cpu_to_le32(EXT_DATA_LBLK);
305 	EXT_FIRST_EXTENT(eh)->ee_len = cpu_to_le16(EXT_DATA_LEN);
306 	ext4_ext_store_pblock(EXT_FIRST_EXTENT(eh), EXT_DATA_PBLK);
307 	if (!param || param->is_unwrit_at_start)
308 		ext4_ext_mark_unwritten(EXT_FIRST_EXTENT(eh));
309 
310 	/* Add stubs */
311 	kunit_activate_static_stub(test, ext4_cache_extents,
312 				   ext4_cache_extents_stub);
313 	kunit_activate_static_stub(test, __ext4_ext_dirty,
314 				   __ext4_ext_dirty_stub);
315 	kunit_activate_static_stub(test, ext4_es_remove_extent,
316 				   ext4_es_remove_extent_stub);
317 	kunit_activate_static_stub(test, ext4_es_insert_extent,
318 				   ext4_es_insert_extent_stub);
319 	kunit_activate_static_stub(test, ext4_zeroout_es, ext4_zeroout_es_stub);
320 	kunit_activate_static_stub(test, ext4_ext_zeroout, ext4_ext_zeroout_stub);
321 	kunit_activate_static_stub(test, ext4_issue_zeroout,
322 				   ext4_issue_zeroout_stub);
323 	return 0;
324 }
325 
326 /*
327  * Return 1 if all bytes in the buf equal to c, else return the offset of first mismatch
328  */
329 static int check_buffer(char *buf, int c, int size)
330 {
331 	void *ret = NULL;
332 
333 	ret = memchr_inv(buf, c, size);
334 	if (ret  == NULL)
335 		return 0;
336 
337 	kunit_log(KERN_ALERT, kunit_get_current_test(),
338 		  "# %s: wrong char found at offset %u (expected:%d got:%d)", __func__,
339 		  (u32)((char *)ret - buf), c, *((char *)ret));
340 	return 1;
341 }
342 
343 /*
344  * Simulate a map block call by first calling ext4_map_query_blocks() to
345  * correctly populate map flags and pblk and then call the
346  * ext4_map_create_blocks() to do actual split and conversion. This is easier
347  * than calling ext4_map_blocks() because that needs mocking a lot of unrelated
348  * functions.
349  */
350 static void ext4_map_create_blocks_helper(struct kunit *test,
351 					  struct inode *inode,
352 					  struct ext4_map_blocks *map,
353 					  int flags)
354 {
355 	int retval = 0;
356 
357 	retval = ext4_map_query_blocks(NULL, inode, map, flags);
358 	if (retval < 0) {
359 		KUNIT_FAIL(test,
360 			   "ext4_map_query_blocks() failed. Cannot proceed\n");
361 		return;
362 	}
363 
364 	ext4_map_create_blocks(NULL, inode, map, flags);
365 }
366 
367 static void test_split_convert(struct kunit *test)
368 {
369 	struct ext4_ext_path *path;
370 	struct inode *inode = &k_ctx.k_ei->vfs_inode;
371 	struct ext4_extent *ex;
372 	struct ext4_map_blocks map;
373 	const struct kunit_ext_test_param *param =
374 		(const struct kunit_ext_test_param *)(test->param_value);
375 	int blkbits = inode->i_sb->s_blocksize_bits;
376 
377 	if (param->is_zeroout_test)
378 		/*
379 		 * Force zeroout by making ext4_ext_insert_extent return ENOSPC
380 		 */
381 		kunit_activate_static_stub(test, ext4_ext_insert_extent,
382 					   ext4_ext_insert_extent_stub);
383 
384 	path = ext4_find_extent(inode, EXT_DATA_LBLK, NULL, 0);
385 	ex = path->p_ext;
386 	KUNIT_EXPECT_EQ(test, EXT_DATA_LBLK, le32_to_cpu(ex->ee_block));
387 	KUNIT_EXPECT_EQ(test, EXT_DATA_LEN, ext4_ext_get_actual_len(ex));
388 	KUNIT_EXPECT_EQ(test, param->is_unwrit_at_start,
389 			ext4_ext_is_unwritten(ex));
390 	if (param->is_zeroout_test)
391 		KUNIT_EXPECT_EQ(test, 0,
392 				check_buffer(k_ctx.k_data, 'X',
393 					     EXT_DATA_LEN << blkbits));
394 
395 	map.m_lblk = param->split_map.m_lblk;
396 	map.m_len = param->split_map.m_len;
397 
398 	switch (param->type) {
399 	case TEST_SPLIT_CONVERT:
400 		path = ext4_split_convert_extents(NULL, inode, &map, path,
401 						  param->split_flags, NULL);
402 		break;
403 	case TEST_CREATE_BLOCKS:
404 		ext4_map_create_blocks_helper(test, inode, &map, param->split_flags);
405 		break;
406 	default:
407 		KUNIT_FAIL(test, "param->type %d not support.", param->type);
408 	}
409 
410 	path = ext4_find_extent(inode, EXT_DATA_LBLK, NULL, 0);
411 	ex = path->p_ext;
412 
413 	for (int i = 0; i < param->nr_exp_ext; i++) {
414 		struct kunit_ext_state exp_ext = param->exp_ext_state[i];
415 
416 		KUNIT_EXPECT_EQ(test, exp_ext.ex_lblk,
417 				le32_to_cpu(ex->ee_block));
418 		KUNIT_EXPECT_EQ(test, exp_ext.ex_len,
419 				ext4_ext_get_actual_len(ex));
420 		KUNIT_EXPECT_EQ(test, exp_ext.is_unwrit,
421 				ext4_ext_is_unwritten(ex));
422 
423 		/* Only printed on failure */
424 		kunit_log(KERN_INFO, test,
425 			  "# [extent %d] exp: lblk:%d len:%d unwrit:%d \n", i,
426 			  exp_ext.ex_lblk, exp_ext.ex_len, exp_ext.is_unwrit);
427 		kunit_log(KERN_INFO, test,
428 			  "# [extent %d] got: lblk:%d len:%d unwrit:%d\n", i,
429 			  le32_to_cpu(ex->ee_block),
430 			  ext4_ext_get_actual_len(ex),
431 			  ext4_ext_is_unwritten(ex));
432 		kunit_log(KERN_INFO, test, "------------------\n");
433 
434 		ex = ex + 1;
435 	}
436 
437 	if (!param->is_zeroout_test)
438 		return;
439 
440 	/*
441 	 * Check that then data area has been zeroed out correctly
442 	 */
443 	for (int i = 0; i < param->nr_exp_data_segs; i++) {
444 		loff_t off, len;
445 		struct kunit_ext_data_state exp_data_seg = param->exp_data_state[i];
446 
447 		off = exp_data_seg.off_blk << blkbits;
448 		len = exp_data_seg.len_blk << blkbits;
449 		KUNIT_EXPECT_EQ_MSG(test, 0,
450 				    check_buffer(k_ctx.k_data + off,
451 						 exp_data_seg.exp_char, len),
452 				    "# corruption in byte range [%lld, %lld)",
453 				    off, len);
454 	}
455 
456 	return;
457 }
458 
459 static const struct kunit_ext_test_param test_split_convert_params[] = {
460 	/* unwrit to writ splits */
461 	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ",
462 	  .type = TEST_SPLIT_CONVERT,
463 	  .is_unwrit_at_start = 1,
464 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
465 	  .split_map = { .m_lblk = EXT_DATA_LBLK, .m_len = 1 },
466 	  .nr_exp_ext = 2,
467 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
468 			       .ex_len = 1,
469 			       .is_unwrit = 0 },
470 			     { .ex_lblk = EXT_DATA_LBLK + 1,
471 			       .ex_len = EXT_DATA_LEN - 1,
472 			       .is_unwrit = 1 } },
473 	  .is_zeroout_test = 0 },
474 	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ",
475 	  .type = TEST_SPLIT_CONVERT,
476 	  .is_unwrit_at_start = 1,
477 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
478 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 1 },
479 	  .nr_exp_ext = 2,
480 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
481 			       .ex_len = 1,
482 			       .is_unwrit = 1 },
483 			     { .ex_lblk = EXT_DATA_LBLK + 1,
484 			       .ex_len = EXT_DATA_LEN - 1,
485 			       .is_unwrit = 0 } },
486 	  .is_zeroout_test = 0 },
487 	{ .desc = "split unwrit extent to 3 extents and convert 2nd half to writ",
488 	  .type = TEST_SPLIT_CONVERT,
489 	  .is_unwrit_at_start = 1,
490 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
491 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 2 },
492 	  .nr_exp_ext = 3,
493 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
494 			       .ex_len = 1,
495 			       .is_unwrit = 1 },
496 			     { .ex_lblk = EXT_DATA_LBLK + 1,
497 			       .ex_len = EXT_DATA_LEN - 2,
498 			       .is_unwrit = 0 },
499 			     { .ex_lblk = EXT_DATA_LBLK + 1 + (EXT_DATA_LEN - 2),
500 			       .ex_len = 1,
501 			       .is_unwrit = 1 } },
502 	  .is_zeroout_test = 0 },
503 
504 	/* writ to unwrit splits */
505 	{ .desc = "split writ extent to 2 extents and convert 1st half unwrit",
506 	  .type = TEST_SPLIT_CONVERT,
507 	  .is_unwrit_at_start = 0,
508 	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
509 	  .split_map = { .m_lblk = EXT_DATA_LBLK, .m_len = 1 },
510 	  .nr_exp_ext = 2,
511 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
512 			       .ex_len = 1,
513 			       .is_unwrit = 1 },
514 			     { .ex_lblk = EXT_DATA_LBLK + 1,
515 			       .ex_len = EXT_DATA_LEN - 1,
516 			       .is_unwrit = 0 } },
517 	  .is_zeroout_test = 0 },
518 	{ .desc = "split writ extent to 2 extents and convert 2nd half unwrit",
519 	  .type = TEST_SPLIT_CONVERT,
520 	  .is_unwrit_at_start = 0,
521 	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
522 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 1 },
523 	  .nr_exp_ext = 2,
524 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
525 			       .ex_len = 1,
526 			       .is_unwrit = 0 },
527 			     { .ex_lblk = EXT_DATA_LBLK + 1,
528 			       .ex_len = EXT_DATA_LEN - 1,
529 			       .is_unwrit = 1 } },
530 	  .is_zeroout_test = 0 },
531 	{ .desc = "split writ extent to 3 extents and convert 2nd half to unwrit",
532 	  .type = TEST_SPLIT_CONVERT,
533 	  .is_unwrit_at_start = 0,
534 	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
535 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 2 },
536 	  .nr_exp_ext = 3,
537 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
538 			       .ex_len = 1,
539 			       .is_unwrit = 0 },
540 			     { .ex_lblk = EXT_DATA_LBLK + 1,
541 			       .ex_len = EXT_DATA_LEN - 2,
542 			       .is_unwrit = 1 },
543 			     { .ex_lblk = EXT_DATA_LBLK + 1 + (EXT_DATA_LEN - 2),
544 			       .ex_len = 1,
545 			       .is_unwrit = 0 } },
546 	  .is_zeroout_test = 0 },
547 
548 	/*
549 	 * ***** zeroout tests *****
550 	 */
551 	/* unwrit to writ splits */
552 	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (zeroout)",
553 	  .type = TEST_SPLIT_CONVERT,
554 	  .is_unwrit_at_start = 1,
555 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
556 	  .split_map = { .m_lblk = EXT_DATA_LBLK, .m_len = 1 },
557 	  .nr_exp_ext = 1,
558 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
559 			       .ex_len = EXT_DATA_LEN,
560 			       .is_unwrit = 0 } },
561 	  .is_zeroout_test = 1,
562 	  .nr_exp_data_segs = 2,
563 	  .exp_data_state = { { .exp_char = 'X', .off_blk = 0, .len_blk = 1 },
564 			      { .exp_char = 0,
565 				.off_blk = 1,
566 				.len_blk = EXT_DATA_LEN - 1 } } },
567 	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (zeroout)",
568 	  .type = TEST_SPLIT_CONVERT,
569 	  .is_unwrit_at_start = 1,
570 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
571 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 1 },
572 	  .nr_exp_ext = 1,
573 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
574 			       .ex_len = EXT_DATA_LEN,
575 			       .is_unwrit = 0 } },
576 	  .is_zeroout_test = 1,
577 	  .nr_exp_data_segs = 2,
578 	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
579 			      { .exp_char = 'X',
580 				.off_blk = 1,
581 				.len_blk = EXT_DATA_LEN - 1 } } },
582 	{ .desc = "split unwrit extent to 3 extents and convert 2nd half writ (zeroout)",
583 	  .type = TEST_SPLIT_CONVERT,
584 	  .is_unwrit_at_start = 1,
585 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
586 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 2 },
587 	  .nr_exp_ext = 1,
588 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
589 			       .ex_len = EXT_DATA_LEN,
590 			       .is_unwrit = 0 } },
591 	  .is_zeroout_test = 1,
592 	  .nr_exp_data_segs = 3,
593 	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
594 			      { .exp_char = 'X',
595 				.off_blk = 1,
596 				.len_blk = EXT_DATA_LEN - 2 },
597 			      { .exp_char = 0,
598 				.off_blk = EXT_DATA_LEN - 1,
599 				.len_blk = 1 } } },
600 };
601 
602 /* Tests to trigger ext4_ext_map_blocks() -> convert_initialized_extent() */
603 static const struct kunit_ext_test_param test_convert_initialized_params[] = {
604 	/* writ to unwrit splits */
605 	{ .desc = "split writ extent to 2 extents and convert 1st half unwrit",
606 	  .type = TEST_CREATE_BLOCKS,
607 	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
608 	  .is_unwrit_at_start = 0,
609 	  .split_map = { .m_lblk = EXT_DATA_LBLK, .m_len = 1 },
610 	  .nr_exp_ext = 2,
611 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
612 			       .ex_len = 1,
613 			       .is_unwrit = 1 },
614 			     { .ex_lblk = EXT_DATA_LBLK + 1,
615 			       .ex_len = EXT_DATA_LEN - 1,
616 			       .is_unwrit = 0 } },
617 	  .is_zeroout_test = 0 },
618 	{ .desc = "split writ extent to 2 extents and convert 2nd half unwrit",
619 	  .type = TEST_CREATE_BLOCKS,
620 	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
621 	  .is_unwrit_at_start = 0,
622 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 1 },
623 	  .nr_exp_ext = 2,
624 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
625 			       .ex_len = 1,
626 			       .is_unwrit = 0 },
627 			     { .ex_lblk = EXT_DATA_LBLK + 1,
628 			       .ex_len = EXT_DATA_LEN - 1,
629 			       .is_unwrit = 1 } },
630 	  .is_zeroout_test = 0 },
631 	{ .desc = "split writ extent to 3 extents and convert 2nd half to unwrit",
632 	  .type = TEST_CREATE_BLOCKS,
633 	  .split_flags = EXT4_GET_BLOCKS_CONVERT_UNWRITTEN,
634 	  .is_unwrit_at_start = 0,
635 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 2 },
636 	  .nr_exp_ext = 3,
637 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
638 			       .ex_len = 1,
639 			       .is_unwrit = 0 },
640 			     { .ex_lblk = EXT_DATA_LBLK + 1,
641 			       .ex_len = EXT_DATA_LEN - 2,
642 			       .is_unwrit = 1 },
643 			     { .ex_lblk = EXT_DATA_LBLK + 1 + (EXT_DATA_LEN - 2),
644 			       .ex_len = 1,
645 			       .is_unwrit = 0 } },
646 	  .is_zeroout_test = 0 },
647 };
648 
649 /* Tests to trigger ext4_ext_map_blocks() -> ext4_ext_handle_unwritten_exntents() */
650 static const struct kunit_ext_test_param test_handle_unwritten_params[] = {
651 	/* unwrit to writ splits via endio path */
652 	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (endio)",
653 	  .type = TEST_CREATE_BLOCKS,
654 	  .is_unwrit_at_start = 1,
655 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
656 	  .split_map = { .m_lblk = EXT_DATA_LBLK, .m_len = 1 },
657 	  .nr_exp_ext = 2,
658 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
659 			       .ex_len = 1,
660 			       .is_unwrit = 0 },
661 			     { .ex_lblk = EXT_DATA_LBLK + 1,
662 			       .ex_len = EXT_DATA_LEN - 1,
663 			       .is_unwrit = 1 } },
664 	  .is_zeroout_test = 0 },
665 	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (endio)",
666 	  .type = TEST_CREATE_BLOCKS,
667 	  .is_unwrit_at_start = 1,
668 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
669 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 1 },
670 	  .nr_exp_ext = 2,
671 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
672 			       .ex_len = 1,
673 			       .is_unwrit = 1 },
674 			     { .ex_lblk = EXT_DATA_LBLK + 1,
675 			       .ex_len = EXT_DATA_LEN - 1,
676 			       .is_unwrit = 0 } },
677 	  .is_zeroout_test = 0 },
678 	{ .desc = "split unwrit extent to 3 extents and convert 2nd half to writ (endio)",
679 	  .type = TEST_CREATE_BLOCKS,
680 	  .is_unwrit_at_start = 1,
681 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
682 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 2 },
683 	  .nr_exp_ext = 3,
684 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
685 			       .ex_len = 1,
686 			       .is_unwrit = 1 },
687 			     { .ex_lblk = EXT_DATA_LBLK + 1,
688 			       .ex_len = EXT_DATA_LEN - 2,
689 			       .is_unwrit = 0 },
690 			     { .ex_lblk = EXT_DATA_LBLK + 1 + (EXT_DATA_LEN - 2),
691 			       .ex_len = 1,
692 			       .is_unwrit = 1 } },
693 	  .is_zeroout_test = 0 },
694 
695 	/* unwrit to writ splits via non-endio path */
696 	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (non endio)",
697 	  .type = TEST_CREATE_BLOCKS,
698 	  .is_unwrit_at_start = 1,
699 	  .split_flags = EXT4_GET_BLOCKS_CREATE,
700 	  .split_map = { .m_lblk = EXT_DATA_LBLK, .m_len = 1 },
701 	  .nr_exp_ext = 2,
702 	  .disable_zeroout = true,
703 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
704 			       .ex_len = 1,
705 			       .is_unwrit = 0 },
706 			     { .ex_lblk = EXT_DATA_LBLK + 1,
707 			       .ex_len = EXT_DATA_LEN - 1,
708 			       .is_unwrit = 1 } },
709 	  .is_zeroout_test = 0 },
710 	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (non endio)",
711 	  .type = TEST_CREATE_BLOCKS,
712 	  .is_unwrit_at_start = 1,
713 	  .split_flags = EXT4_GET_BLOCKS_CREATE,
714 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 1 },
715 	  .nr_exp_ext = 2,
716 	  .disable_zeroout = true,
717 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
718 			       .ex_len = 1,
719 			       .is_unwrit = 1 },
720 			     { .ex_lblk = EXT_DATA_LBLK + 1,
721 			       .ex_len = EXT_DATA_LEN - 1,
722 			       .is_unwrit = 0 } },
723 	  .is_zeroout_test = 0 },
724 	{ .desc = "split unwrit extent to 3 extents and convert 2nd half to writ (non endio)",
725 	  .type = TEST_CREATE_BLOCKS,
726 	  .is_unwrit_at_start = 1,
727 	  .split_flags = EXT4_GET_BLOCKS_CREATE,
728 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 2 },
729 	  .nr_exp_ext = 3,
730 	  .disable_zeroout = true,
731 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
732 			       .ex_len = 1,
733 			       .is_unwrit = 1 },
734 			     { .ex_lblk = EXT_DATA_LBLK + 1,
735 			       .ex_len = EXT_DATA_LEN - 2,
736 			       .is_unwrit = 0 },
737 			     { .ex_lblk = EXT_DATA_LBLK + 1 + (EXT_DATA_LEN - 2),
738 			       .ex_len = 1,
739 			       .is_unwrit = 1 } },
740 	  .is_zeroout_test = 0 },
741 
742 	/*
743 	 * ***** zeroout tests *****
744 	 */
745 	/* unwrit to writ splits (endio)*/
746 	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (endio, zeroout)",
747 	  .type = TEST_CREATE_BLOCKS,
748 	  .is_unwrit_at_start = 1,
749 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
750 	  .split_map = { .m_lblk = EXT_DATA_LBLK, .m_len = 1 },
751 	  .nr_exp_ext = 1,
752 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
753 			       .ex_len = EXT_DATA_LEN,
754 			       .is_unwrit = 0 } },
755 	  .is_zeroout_test = 1,
756 	  .nr_exp_data_segs = 2,
757 	  .exp_data_state = { { .exp_char = 'X', .off_blk = 0, .len_blk = 1 },
758 			      { .exp_char = 0,
759 				.off_blk = 1,
760 				.len_blk = EXT_DATA_LEN - 1 } } },
761 	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (endio, zeroout)",
762 	  .type = TEST_CREATE_BLOCKS,
763 	  .is_unwrit_at_start = 1,
764 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
765 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 1 },
766 	  .nr_exp_ext = 1,
767 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
768 			       .ex_len = EXT_DATA_LEN,
769 			       .is_unwrit = 0 } },
770 	  .is_zeroout_test = 1,
771 	  .nr_exp_data_segs = 2,
772 	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
773 			      { .exp_char = 'X',
774 				.off_blk = 1,
775 				.len_blk = EXT_DATA_LEN - 1 } } },
776 	{ .desc = "split unwrit extent to 3 extents and convert 2nd half writ (endio, zeroout)",
777 	  .type = TEST_CREATE_BLOCKS,
778 	  .is_unwrit_at_start = 1,
779 	  .split_flags = EXT4_GET_BLOCKS_CONVERT,
780 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 2 },
781 	  .nr_exp_ext = 1,
782 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
783 			       .ex_len = EXT_DATA_LEN,
784 			       .is_unwrit = 0 } },
785 	  .is_zeroout_test = 1,
786 	  .nr_exp_data_segs = 3,
787 	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
788 			      { .exp_char = 'X',
789 				.off_blk = 1,
790 				.len_blk = EXT_DATA_LEN - 2 },
791 			      { .exp_char = 0,
792 				.off_blk = EXT_DATA_LEN - 1,
793 				.len_blk = 1 } } },
794 
795 	/* unwrit to writ splits (non-endio)*/
796 	{ .desc = "split unwrit extent to 2 extents and convert 1st half writ (non-endio, zeroout)",
797 	  .type = TEST_CREATE_BLOCKS,
798 	  .is_unwrit_at_start = 1,
799 	  .split_flags = EXT4_GET_BLOCKS_CREATE,
800 	  .split_map = { .m_lblk = EXT_DATA_LBLK, .m_len = 1 },
801 	  .nr_exp_ext = 1,
802 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
803 			       .ex_len = EXT_DATA_LEN,
804 			       .is_unwrit = 0 } },
805 	  .is_zeroout_test = 1,
806 	  .nr_exp_data_segs = 2,
807 	  .exp_data_state = { { .exp_char = 'X', .off_blk = 0, .len_blk = 1 },
808 			      { .exp_char = 0,
809 				.off_blk = 1,
810 				.len_blk = EXT_DATA_LEN - 1 } } },
811 	{ .desc = "split unwrit extent to 2 extents and convert 2nd half writ (non-endio, zeroout)",
812 	  .type = TEST_CREATE_BLOCKS,
813 	  .is_unwrit_at_start = 1,
814 	  .split_flags = EXT4_GET_BLOCKS_CREATE,
815 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 1 },
816 	  .nr_exp_ext = 1,
817 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
818 			       .ex_len = EXT_DATA_LEN,
819 			       .is_unwrit = 0 } },
820 	  .is_zeroout_test = 1,
821 	  .nr_exp_data_segs = 2,
822 	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
823 			      { .exp_char = 'X',
824 				.off_blk = 1,
825 				.len_blk = EXT_DATA_LEN - 1 } } },
826 	{ .desc = "split unwrit extent to 3 extents and convert 2nd half writ (non-endio, zeroout)",
827 	  .type = TEST_CREATE_BLOCKS,
828 	  .is_unwrit_at_start = 1,
829 	  .split_flags = EXT4_GET_BLOCKS_CREATE,
830 	  .split_map = { .m_lblk = EXT_DATA_LBLK + 1, .m_len = EXT_DATA_LEN - 2 },
831 	  .nr_exp_ext = 1,
832 	  .exp_ext_state = { { .ex_lblk = EXT_DATA_LBLK,
833 			       .ex_len = EXT_DATA_LEN,
834 			       .is_unwrit = 0 } },
835 	  .is_zeroout_test = 1,
836 	  .nr_exp_data_segs = 3,
837 	  .exp_data_state = { { .exp_char = 0, .off_blk = 0, .len_blk = 1 },
838 			      { .exp_char = 'X',
839 				.off_blk = 1,
840 				.len_blk = EXT_DATA_LEN - 2 },
841 			      { .exp_char = 0,
842 				.off_blk = EXT_DATA_LEN - 1,
843 				.len_blk = 1 } } },
844 };
845 
846 static void ext_get_desc(struct kunit *test, const void *p, char *desc)
847 
848 {
849 	struct kunit_ext_test_param *param = (struct kunit_ext_test_param *)p;
850 
851 	snprintf(desc, KUNIT_PARAM_DESC_SIZE, "%s %s\n", param->desc,
852 		 (param->type & TEST_CREATE_BLOCKS) ? "(highlevel)" : "");
853 }
854 
855 static int test_split_convert_param_init(struct kunit *test)
856 {
857 	size_t arr_size = ARRAY_SIZE(test_split_convert_params);
858 
859 	kunit_register_params_array(test, test_split_convert_params, arr_size,
860 				    ext_get_desc);
861 	return 0;
862 }
863 
864 static int test_convert_initialized_param_init(struct kunit *test)
865 {
866 	size_t arr_size = ARRAY_SIZE(test_convert_initialized_params);
867 
868 	kunit_register_params_array(test, test_convert_initialized_params,
869 				    arr_size, ext_get_desc);
870 	return 0;
871 }
872 
873 static int test_handle_unwritten_init(struct kunit *test)
874 {
875 	size_t arr_size = ARRAY_SIZE(test_handle_unwritten_params);
876 
877 	kunit_register_params_array(test, test_handle_unwritten_params,
878 				    arr_size, ext_get_desc);
879 	return 0;
880 }
881 
882 /*
883  * Note that we use KUNIT_CASE_PARAM_WITH_INIT() instead of the more compact
884  * KUNIT_ARRAY_PARAM() because the later currently has a limitation causing the
885  * output parsing to be prone to error. For more context:
886  *
887  * https://lore.kernel.org/linux-kselftest/aULJpTvJDw9ctUDe@li-dc0c254c-257c-11b2-a85c-98b6c1322444.ibm.com/
888  */
889 static struct kunit_case extents_test_cases[] = {
890 	KUNIT_CASE_PARAM_WITH_INIT(test_split_convert, kunit_array_gen_params,
891 				   test_split_convert_param_init, NULL),
892 	KUNIT_CASE_PARAM_WITH_INIT(test_split_convert, kunit_array_gen_params,
893 				   test_convert_initialized_param_init, NULL),
894 	KUNIT_CASE_PARAM_WITH_INIT(test_split_convert, kunit_array_gen_params,
895 				   test_handle_unwritten_init, NULL),
896 	{}
897 };
898 
899 static struct kunit_suite extents_test_suite = {
900 	.name = "ext4_extents_test",
901 	.init = extents_kunit_init,
902 	.exit = extents_kunit_exit,
903 	.test_cases = extents_test_cases,
904 };
905 
906 kunit_test_suites(&extents_test_suite);
907 
908 MODULE_LICENSE("GPL");
909