1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2019 Intel Corporation
4  * Copyright © 2022 Maíra Canal <mairacanal@riseup.net>
5  */
6 
7 #include <kunit/test.h>
8 
9 #include <linux/prime_numbers.h>
10 #include <linux/sched/signal.h>
11 
12 #include <drm/drm_buddy.h>
13 
14 #include "../lib/drm_random.h"
15 
16 #define TIMEOUT(name__)								\
17 	unsigned long name__ = jiffies + MAX_SCHEDULE_TIMEOUT
18 
19 static unsigned int random_seed;
20 
21 static inline u64 get_size(int order, u64 chunk_size)
22 {
23 	return (1 << order) * chunk_size;
24 }
25 
26 __printf(2, 3)
27 static bool __timeout(unsigned long timeout, const char *fmt, ...)
28 {
29 	va_list va;
30 
31 	if (!signal_pending(current)) {
32 		cond_resched();
33 		if (time_before(jiffies, timeout))
34 			return false;
35 	}
36 
37 	if (fmt) {
38 		va_start(va, fmt);
39 		vprintk(fmt, va);
40 		va_end(va);
41 	}
42 
43 	return true;
44 }
45 
46 static void __dump_block(struct kunit *test, struct drm_buddy *mm,
47 			 struct drm_buddy_block *block, bool buddy)
48 {
49 	kunit_err(test, "block info: header=%llx, state=%u, order=%d, offset=%llx size=%llx root=%d buddy=%d\n",
50 		  block->header, drm_buddy_block_state(block),
51 			  drm_buddy_block_order(block), drm_buddy_block_offset(block),
52 			  drm_buddy_block_size(mm, block), !block->parent, buddy);
53 }
54 
55 static void dump_block(struct kunit *test, struct drm_buddy *mm,
56 		       struct drm_buddy_block *block)
57 {
58 	struct drm_buddy_block *buddy;
59 
60 	__dump_block(test, mm, block, false);
61 
62 	buddy = drm_get_buddy(block);
63 	if (buddy)
64 		__dump_block(test, mm, buddy, true);
65 }
66 
67 static int check_block(struct kunit *test, struct drm_buddy *mm,
68 		       struct drm_buddy_block *block)
69 {
70 	struct drm_buddy_block *buddy;
71 	unsigned int block_state;
72 	u64 block_size;
73 	u64 offset;
74 	int err = 0;
75 
76 	block_state = drm_buddy_block_state(block);
77 
78 	if (block_state != DRM_BUDDY_ALLOCATED &&
79 	    block_state != DRM_BUDDY_FREE && block_state != DRM_BUDDY_SPLIT) {
80 		kunit_err(test, "block state mismatch\n");
81 		err = -EINVAL;
82 	}
83 
84 	block_size = drm_buddy_block_size(mm, block);
85 	offset = drm_buddy_block_offset(block);
86 
87 	if (block_size < mm->chunk_size) {
88 		kunit_err(test, "block size smaller than min size\n");
89 		err = -EINVAL;
90 	}
91 
92 	/* We can't use is_power_of_2() for a u64 on 32-bit systems. */
93 	if (block_size & (block_size - 1)) {
94 		kunit_err(test, "block size not power of two\n");
95 		err = -EINVAL;
96 	}
97 
98 	if (!IS_ALIGNED(block_size, mm->chunk_size)) {
99 		kunit_err(test, "block size not aligned to min size\n");
100 		err = -EINVAL;
101 	}
102 
103 	if (!IS_ALIGNED(offset, mm->chunk_size)) {
104 		kunit_err(test, "block offset not aligned to min size\n");
105 		err = -EINVAL;
106 	}
107 
108 	if (!IS_ALIGNED(offset, block_size)) {
109 		kunit_err(test, "block offset not aligned to block size\n");
110 		err = -EINVAL;
111 	}
112 
113 	buddy = drm_get_buddy(block);
114 
115 	if (!buddy && block->parent) {
116 		kunit_err(test, "buddy has gone fishing\n");
117 		err = -EINVAL;
118 	}
119 
120 	if (buddy) {
121 		if (drm_buddy_block_offset(buddy) != (offset ^ block_size)) {
122 			kunit_err(test, "buddy has wrong offset\n");
123 			err = -EINVAL;
124 		}
125 
126 		if (drm_buddy_block_size(mm, buddy) != block_size) {
127 			kunit_err(test, "buddy size mismatch\n");
128 			err = -EINVAL;
129 		}
130 
131 		if (drm_buddy_block_state(buddy) == block_state &&
132 		    block_state == DRM_BUDDY_FREE) {
133 			kunit_err(test, "block and its buddy are free\n");
134 			err = -EINVAL;
135 		}
136 	}
137 
138 	return err;
139 }
140 
141 static int check_blocks(struct kunit *test, struct drm_buddy *mm,
142 			struct list_head *blocks, u64 expected_size, bool is_contiguous)
143 {
144 	struct drm_buddy_block *block;
145 	struct drm_buddy_block *prev;
146 	u64 total;
147 	int err = 0;
148 
149 	block = NULL;
150 	prev = NULL;
151 	total = 0;
152 
153 	list_for_each_entry(block, blocks, link) {
154 		err = check_block(test, mm, block);
155 
156 		if (!drm_buddy_block_is_allocated(block)) {
157 			kunit_err(test, "block not allocated\n");
158 			err = -EINVAL;
159 		}
160 
161 		if (is_contiguous && prev) {
162 			u64 prev_block_size;
163 			u64 prev_offset;
164 			u64 offset;
165 
166 			prev_offset = drm_buddy_block_offset(prev);
167 			prev_block_size = drm_buddy_block_size(mm, prev);
168 			offset = drm_buddy_block_offset(block);
169 
170 			if (offset != (prev_offset + prev_block_size)) {
171 				kunit_err(test, "block offset mismatch\n");
172 				err = -EINVAL;
173 			}
174 		}
175 
176 		if (err)
177 			break;
178 
179 		total += drm_buddy_block_size(mm, block);
180 		prev = block;
181 	}
182 
183 	if (!err) {
184 		if (total != expected_size) {
185 			kunit_err(test, "size mismatch, expected=%llx, found=%llx\n",
186 				  expected_size, total);
187 			err = -EINVAL;
188 		}
189 		return err;
190 	}
191 
192 	if (prev) {
193 		kunit_err(test, "prev block, dump:\n");
194 		dump_block(test, mm, prev);
195 	}
196 
197 	kunit_err(test, "bad block, dump:\n");
198 	dump_block(test, mm, block);
199 
200 	return err;
201 }
202 
203 static int check_mm(struct kunit *test, struct drm_buddy *mm)
204 {
205 	struct drm_buddy_block *root;
206 	struct drm_buddy_block *prev;
207 	unsigned int i;
208 	u64 total;
209 	int err = 0;
210 
211 	if (!mm->n_roots) {
212 		kunit_err(test, "n_roots is zero\n");
213 		return -EINVAL;
214 	}
215 
216 	if (mm->n_roots != hweight64(mm->size)) {
217 		kunit_err(test, "n_roots mismatch, n_roots=%u, expected=%lu\n",
218 			  mm->n_roots, hweight64(mm->size));
219 		return -EINVAL;
220 	}
221 
222 	root = NULL;
223 	prev = NULL;
224 	total = 0;
225 
226 	for (i = 0; i < mm->n_roots; ++i) {
227 		struct drm_buddy_block *block;
228 		unsigned int order;
229 
230 		root = mm->roots[i];
231 		if (!root) {
232 			kunit_err(test, "root(%u) is NULL\n", i);
233 			err = -EINVAL;
234 			break;
235 		}
236 
237 		err = check_block(test, mm, root);
238 
239 		if (!drm_buddy_block_is_free(root)) {
240 			kunit_err(test, "root not free\n");
241 			err = -EINVAL;
242 		}
243 
244 		order = drm_buddy_block_order(root);
245 
246 		if (!i) {
247 			if (order != mm->max_order) {
248 				kunit_err(test, "max order root missing\n");
249 				err = -EINVAL;
250 			}
251 		}
252 
253 		if (prev) {
254 			u64 prev_block_size;
255 			u64 prev_offset;
256 			u64 offset;
257 
258 			prev_offset = drm_buddy_block_offset(prev);
259 			prev_block_size = drm_buddy_block_size(mm, prev);
260 			offset = drm_buddy_block_offset(root);
261 
262 			if (offset != (prev_offset + prev_block_size)) {
263 				kunit_err(test, "root offset mismatch\n");
264 				err = -EINVAL;
265 			}
266 		}
267 
268 		block = list_first_entry_or_null(&mm->free_list[order],
269 						 struct drm_buddy_block, link);
270 		if (block != root) {
271 			kunit_err(test, "root mismatch at order=%u\n", order);
272 			err = -EINVAL;
273 		}
274 
275 		if (err)
276 			break;
277 
278 		prev = root;
279 		total += drm_buddy_block_size(mm, root);
280 	}
281 
282 	if (!err) {
283 		if (total != mm->size) {
284 			kunit_err(test, "expected mm size=%llx, found=%llx\n",
285 				  mm->size, total);
286 			err = -EINVAL;
287 		}
288 		return err;
289 	}
290 
291 	if (prev) {
292 		kunit_err(test, "prev root(%u), dump:\n", i - 1);
293 		dump_block(test, mm, prev);
294 	}
295 
296 	if (root) {
297 		kunit_err(test, "bad root(%u), dump:\n", i);
298 		dump_block(test, mm, root);
299 	}
300 
301 	return err;
302 }
303 
304 static void mm_config(u64 *size, u64 *chunk_size)
305 {
306 	DRM_RND_STATE(prng, random_seed);
307 	u32 s, ms;
308 
309 	/* Nothing fancy, just try to get an interesting bit pattern */
310 
311 	prandom_seed_state(&prng, random_seed);
312 
313 	/* Let size be a random number of pages up to 8 GB (2M pages) */
314 	s = 1 + drm_prandom_u32_max_state((BIT(33 - 12)) - 1, &prng);
315 	/* Let the chunk size be a random power of 2 less than size */
316 	ms = BIT(drm_prandom_u32_max_state(ilog2(s), &prng));
317 	/* Round size down to the chunk size */
318 	s &= -ms;
319 
320 	/* Convert from pages to bytes */
321 	*chunk_size = (u64)ms << 12;
322 	*size = (u64)s << 12;
323 }
324 
325 static void drm_test_buddy_alloc_pathological(struct kunit *test)
326 {
327 	u64 mm_size, size, start = 0;
328 	struct drm_buddy_block *block;
329 	const int max_order = 3;
330 	unsigned long flags = 0;
331 	int order, top;
332 	struct drm_buddy mm;
333 	LIST_HEAD(blocks);
334 	LIST_HEAD(holes);
335 	LIST_HEAD(tmp);
336 
337 	/*
338 	 * Create a pot-sized mm, then allocate one of each possible
339 	 * order within. This should leave the mm with exactly one
340 	 * page left. Free the largest block, then whittle down again.
341 	 * Eventually we will have a fully 50% fragmented mm.
342 	 */
343 
344 	mm_size = PAGE_SIZE << max_order;
345 	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_init(&mm, mm_size, PAGE_SIZE),
346 			       "buddy_init failed\n");
347 
348 	KUNIT_EXPECT_EQ(test, mm.max_order, max_order);
349 
350 	for (top = max_order; top; top--) {
351 		/* Make room by freeing the largest allocated block */
352 		block = list_first_entry_or_null(&blocks, typeof(*block), link);
353 		if (block) {
354 			list_del(&block->link);
355 			drm_buddy_free_block(&mm, block);
356 		}
357 
358 		for (order = top; order--;) {
359 			size = get_size(order, PAGE_SIZE);
360 			KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, start,
361 									    mm_size, size, size,
362 										&tmp, flags),
363 					"buddy_alloc hit -ENOMEM with order=%d, top=%d\n",
364 					order, top);
365 
366 			block = list_first_entry_or_null(&tmp, struct drm_buddy_block, link);
367 			KUNIT_ASSERT_TRUE_MSG(test, block, "alloc_blocks has no blocks\n");
368 
369 			list_move_tail(&block->link, &blocks);
370 		}
371 
372 		/* There should be one final page for this sub-allocation */
373 		size = get_size(0, PAGE_SIZE);
374 		KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
375 								    size, size, &tmp, flags),
376 							   "buddy_alloc hit -ENOMEM for hole\n");
377 
378 		block = list_first_entry_or_null(&tmp, struct drm_buddy_block, link);
379 		KUNIT_ASSERT_TRUE_MSG(test, block, "alloc_blocks has no blocks\n");
380 
381 		list_move_tail(&block->link, &holes);
382 
383 		size = get_size(top, PAGE_SIZE);
384 		KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
385 								   size, size, &tmp, flags),
386 							  "buddy_alloc unexpectedly succeeded at top-order %d/%d, it should be full!",
387 							  top, max_order);
388 	}
389 
390 	drm_buddy_free_list(&mm, &holes);
391 
392 	/* Nothing larger than blocks of chunk_size now available */
393 	for (order = 1; order <= max_order; order++) {
394 		size = get_size(order, PAGE_SIZE);
395 		KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
396 								   size, size, &tmp, flags),
397 							  "buddy_alloc unexpectedly succeeded at order %d, it should be full!",
398 							  order);
399 	}
400 
401 	list_splice_tail(&holes, &blocks);
402 	drm_buddy_free_list(&mm, &blocks);
403 	drm_buddy_fini(&mm);
404 }
405 
406 static void drm_test_buddy_alloc_smoke(struct kunit *test)
407 {
408 	u64 mm_size, chunk_size, start = 0;
409 	unsigned long flags = 0;
410 	struct drm_buddy mm;
411 	int *order;
412 	int i;
413 
414 	DRM_RND_STATE(prng, random_seed);
415 	TIMEOUT(end_time);
416 
417 	mm_config(&mm_size, &chunk_size);
418 
419 	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_init(&mm, mm_size, chunk_size),
420 			       "buddy_init failed\n");
421 
422 	order = drm_random_order(mm.max_order + 1, &prng);
423 	KUNIT_ASSERT_TRUE(test, order);
424 
425 	for (i = 0; i <= mm.max_order; ++i) {
426 		struct drm_buddy_block *block;
427 		int max_order = order[i];
428 		bool timeout = false;
429 		LIST_HEAD(blocks);
430 		u64 total, size;
431 		LIST_HEAD(tmp);
432 		int order, err;
433 
434 		KUNIT_ASSERT_FALSE_MSG(test, check_mm(test, &mm),
435 				       "pre-mm check failed, abort\n");
436 
437 		order = max_order;
438 		total = 0;
439 
440 		do {
441 retry:
442 			size = get_size(order, chunk_size);
443 			err = drm_buddy_alloc_blocks(&mm, start, mm_size, size, size, &tmp, flags);
444 			if (err) {
445 				if (err == -ENOMEM) {
446 					KUNIT_FAIL(test, "buddy_alloc hit -ENOMEM with order=%d\n",
447 						   order);
448 				} else {
449 					if (order--) {
450 						err = 0;
451 						goto retry;
452 					}
453 
454 					KUNIT_FAIL(test, "buddy_alloc with order=%d failed\n",
455 						   order);
456 				}
457 
458 				break;
459 			}
460 
461 			block = list_first_entry_or_null(&tmp, struct drm_buddy_block, link);
462 			KUNIT_ASSERT_TRUE_MSG(test, block, "alloc_blocks has no blocks\n");
463 
464 			list_move_tail(&block->link, &blocks);
465 			KUNIT_EXPECT_EQ_MSG(test, drm_buddy_block_order(block), order,
466 					    "buddy_alloc order mismatch\n");
467 
468 			total += drm_buddy_block_size(&mm, block);
469 
470 			if (__timeout(end_time, NULL)) {
471 				timeout = true;
472 				break;
473 			}
474 		} while (total < mm.size);
475 
476 		if (!err)
477 			err = check_blocks(test, &mm, &blocks, total, false);
478 
479 		drm_buddy_free_list(&mm, &blocks);
480 
481 		if (!err) {
482 			KUNIT_EXPECT_FALSE_MSG(test, check_mm(test, &mm),
483 					       "post-mm check failed\n");
484 		}
485 
486 		if (err || timeout)
487 			break;
488 
489 		cond_resched();
490 	}
491 
492 	kfree(order);
493 	drm_buddy_fini(&mm);
494 }
495 
496 static void drm_test_buddy_alloc_pessimistic(struct kunit *test)
497 {
498 	u64 mm_size, size, start = 0;
499 	struct drm_buddy_block *block, *bn;
500 	const unsigned int max_order = 16;
501 	unsigned long flags = 0;
502 	struct drm_buddy mm;
503 	unsigned int order;
504 	LIST_HEAD(blocks);
505 	LIST_HEAD(tmp);
506 
507 	/*
508 	 * Create a pot-sized mm, then allocate one of each possible
509 	 * order within. This should leave the mm with exactly one
510 	 * page left.
511 	 */
512 
513 	mm_size = PAGE_SIZE << max_order;
514 	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_init(&mm, mm_size, PAGE_SIZE),
515 			       "buddy_init failed\n");
516 
517 	KUNIT_EXPECT_EQ(test, mm.max_order, max_order);
518 
519 	for (order = 0; order < max_order; order++) {
520 		size = get_size(order, PAGE_SIZE);
521 		KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
522 								    size, size, &tmp, flags),
523 							   "buddy_alloc hit -ENOMEM with order=%d\n",
524 							   order);
525 
526 		block = list_first_entry_or_null(&tmp, struct drm_buddy_block, link);
527 		KUNIT_ASSERT_TRUE_MSG(test, block, "alloc_blocks has no blocks\n");
528 
529 		list_move_tail(&block->link, &blocks);
530 	}
531 
532 	/* And now the last remaining block available */
533 	size = get_size(0, PAGE_SIZE);
534 	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
535 							    size, size, &tmp, flags),
536 						   "buddy_alloc hit -ENOMEM on final alloc\n");
537 
538 	block = list_first_entry_or_null(&tmp, struct drm_buddy_block, link);
539 	KUNIT_ASSERT_TRUE_MSG(test, block, "alloc_blocks has no blocks\n");
540 
541 	list_move_tail(&block->link, &blocks);
542 
543 	/* Should be completely full! */
544 	for (order = max_order; order--;) {
545 		size = get_size(order, PAGE_SIZE);
546 		KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
547 								   size, size, &tmp, flags),
548 							  "buddy_alloc unexpectedly succeeded, it should be full!");
549 	}
550 
551 	block = list_last_entry(&blocks, typeof(*block), link);
552 	list_del(&block->link);
553 	drm_buddy_free_block(&mm, block);
554 
555 	/* As we free in increasing size, we make available larger blocks */
556 	order = 1;
557 	list_for_each_entry_safe(block, bn, &blocks, link) {
558 		list_del(&block->link);
559 		drm_buddy_free_block(&mm, block);
560 
561 		size = get_size(order, PAGE_SIZE);
562 		KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
563 								    size, size, &tmp, flags),
564 							   "buddy_alloc hit -ENOMEM with order=%d\n",
565 							   order);
566 
567 		block = list_first_entry_or_null(&tmp, struct drm_buddy_block, link);
568 		KUNIT_ASSERT_TRUE_MSG(test, block, "alloc_blocks has no blocks\n");
569 
570 		list_del(&block->link);
571 		drm_buddy_free_block(&mm, block);
572 		order++;
573 	}
574 
575 	/* To confirm, now the whole mm should be available */
576 	size = get_size(max_order, PAGE_SIZE);
577 	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
578 							    size, size, &tmp, flags),
579 						   "buddy_alloc (realloc) hit -ENOMEM with order=%d\n",
580 						   max_order);
581 
582 	block = list_first_entry_or_null(&tmp, struct drm_buddy_block, link);
583 	KUNIT_ASSERT_TRUE_MSG(test, block, "alloc_blocks has no blocks\n");
584 
585 	list_del(&block->link);
586 	drm_buddy_free_block(&mm, block);
587 	drm_buddy_free_list(&mm, &blocks);
588 	drm_buddy_fini(&mm);
589 }
590 
591 static void drm_test_buddy_alloc_optimistic(struct kunit *test)
592 {
593 	u64 mm_size, size, start = 0;
594 	struct drm_buddy_block *block;
595 	unsigned long flags = 0;
596 	const int max_order = 16;
597 	struct drm_buddy mm;
598 	LIST_HEAD(blocks);
599 	LIST_HEAD(tmp);
600 	int order;
601 
602 	/*
603 	 * Create a mm with one block of each order available, and
604 	 * try to allocate them all.
605 	 */
606 
607 	mm_size = PAGE_SIZE * ((1 << (max_order + 1)) - 1);
608 
609 	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_init(&mm, mm_size, PAGE_SIZE),
610 			       "buddy_init failed\n");
611 
612 	KUNIT_EXPECT_EQ(test, mm.max_order, max_order);
613 
614 	for (order = 0; order <= max_order; order++) {
615 		size = get_size(order, PAGE_SIZE);
616 		KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
617 								    size, size, &tmp, flags),
618 							   "buddy_alloc hit -ENOMEM with order=%d\n",
619 							   order);
620 
621 		block = list_first_entry_or_null(&tmp, struct drm_buddy_block, link);
622 		KUNIT_ASSERT_TRUE_MSG(test, block, "alloc_blocks has no blocks\n");
623 
624 		list_move_tail(&block->link, &blocks);
625 	}
626 
627 	/* Should be completely full! */
628 	size = get_size(0, PAGE_SIZE);
629 	KUNIT_ASSERT_TRUE_MSG(test, drm_buddy_alloc_blocks(&mm, start, mm_size,
630 							   size, size, &tmp, flags),
631 						  "buddy_alloc unexpectedly succeeded, it should be full!");
632 
633 	drm_buddy_free_list(&mm, &blocks);
634 	drm_buddy_fini(&mm);
635 }
636 
637 static void drm_test_buddy_alloc_range(struct kunit *test)
638 {
639 	unsigned long flags = DRM_BUDDY_RANGE_ALLOCATION;
640 	u64 offset, size, rem, chunk_size, end;
641 	unsigned long page_num;
642 	struct drm_buddy mm;
643 	LIST_HEAD(blocks);
644 
645 	mm_config(&size, &chunk_size);
646 
647 	KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_init(&mm, size, chunk_size),
648 			       "buddy_init failed");
649 
650 	KUNIT_ASSERT_FALSE_MSG(test, check_mm(test, &mm),
651 			       "pre-mm check failed, abort!");
652 
653 	rem = mm.size;
654 	offset = 0;
655 
656 	for_each_prime_number_from(page_num, 1, ULONG_MAX - 1) {
657 		struct drm_buddy_block *block;
658 		LIST_HEAD(tmp);
659 
660 		size = min(page_num * mm.chunk_size, rem);
661 		end = offset + size;
662 
663 		KUNIT_ASSERT_FALSE_MSG(test, drm_buddy_alloc_blocks(&mm, offset, end,
664 								    size, mm.chunk_size,
665 									&tmp, flags),
666 				"alloc_range with offset=%llx, size=%llx failed\n", offset, size);
667 
668 		block = list_first_entry_or_null(&tmp, struct drm_buddy_block, link);
669 		KUNIT_ASSERT_TRUE_MSG(test, block, "alloc_range has no blocks\n");
670 
671 		KUNIT_ASSERT_EQ_MSG(test, drm_buddy_block_offset(block), offset,
672 				    "alloc_range start offset mismatch, found=%llx, expected=%llx\n",
673 							drm_buddy_block_offset(block), offset);
674 
675 		KUNIT_ASSERT_FALSE(test, check_blocks(test, &mm, &tmp, size, true));
676 
677 		list_splice_tail(&tmp, &blocks);
678 
679 		offset += size;
680 
681 		rem -= size;
682 		if (!rem)
683 			break;
684 
685 		cond_resched();
686 	}
687 
688 	drm_buddy_free_list(&mm, &blocks);
689 
690 	KUNIT_EXPECT_FALSE_MSG(test, check_mm(test, &mm), "post-mm check failed\n");
691 
692 	drm_buddy_fini(&mm);
693 }
694 
695 static void drm_test_buddy_alloc_limit(struct kunit *test)
696 {
697 	u64 size = U64_MAX, start = 0;
698 	struct drm_buddy_block *block;
699 	unsigned long flags = 0;
700 	LIST_HEAD(allocated);
701 	struct drm_buddy mm;
702 
703 	KUNIT_EXPECT_FALSE(test, drm_buddy_init(&mm, size, PAGE_SIZE));
704 
705 	KUNIT_EXPECT_EQ_MSG(test, mm.max_order, DRM_BUDDY_MAX_ORDER,
706 			    "mm.max_order(%d) != %d\n", mm.max_order,
707 						DRM_BUDDY_MAX_ORDER);
708 
709 	size = mm.chunk_size << mm.max_order;
710 	KUNIT_EXPECT_FALSE(test, drm_buddy_alloc_blocks(&mm, start, size, size,
711 							PAGE_SIZE, &allocated, flags));
712 
713 	block = list_first_entry_or_null(&allocated, struct drm_buddy_block, link);
714 	KUNIT_EXPECT_TRUE(test, block);
715 
716 	KUNIT_EXPECT_EQ_MSG(test, drm_buddy_block_order(block), mm.max_order,
717 			    "block order(%d) != %d\n",
718 						drm_buddy_block_order(block), mm.max_order);
719 
720 	KUNIT_EXPECT_EQ_MSG(test, drm_buddy_block_size(&mm, block),
721 			    BIT_ULL(mm.max_order) * PAGE_SIZE,
722 						"block size(%llu) != %llu\n",
723 						drm_buddy_block_size(&mm, block),
724 						BIT_ULL(mm.max_order) * PAGE_SIZE);
725 
726 	drm_buddy_free_list(&mm, &allocated);
727 	drm_buddy_fini(&mm);
728 }
729 
730 static int drm_buddy_suite_init(struct kunit_suite *suite)
731 {
732 	while (!random_seed)
733 		random_seed = get_random_u32();
734 
735 	kunit_info(suite, "Testing DRM buddy manager, with random_seed=0x%x\n", random_seed);
736 
737 	return 0;
738 }
739 
740 static struct kunit_case drm_buddy_tests[] = {
741 	KUNIT_CASE(drm_test_buddy_alloc_limit),
742 	KUNIT_CASE(drm_test_buddy_alloc_range),
743 	KUNIT_CASE(drm_test_buddy_alloc_optimistic),
744 	KUNIT_CASE(drm_test_buddy_alloc_pessimistic),
745 	KUNIT_CASE(drm_test_buddy_alloc_smoke),
746 	KUNIT_CASE(drm_test_buddy_alloc_pathological),
747 	{}
748 };
749 
750 static struct kunit_suite drm_buddy_test_suite = {
751 	.name = "drm_buddy",
752 	.suite_init = drm_buddy_suite_init,
753 	.test_cases = drm_buddy_tests,
754 };
755 
756 kunit_test_suite(drm_buddy_test_suite);
757 
758 MODULE_AUTHOR("Intel Corporation");
759 MODULE_LICENSE("GPL");
760