1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2015 Facebook.  All rights reserved.
4  */
5 
6 #include <linux/types.h>
7 #include "btrfs-tests.h"
8 #include "../ctree.h"
9 #include "../disk-io.h"
10 #include "../free-space-tree.h"
11 #include "../transaction.h"
12 #include "../block-group.h"
13 #include "../accessors.h"
14 
15 struct free_space_extent {
16 	u64 start;
17 	u64 length;
18 };
19 
20 static int __check_free_space_extents(struct btrfs_trans_handle *trans,
21 				      struct btrfs_fs_info *fs_info,
22 				      struct btrfs_block_group *cache,
23 				      struct btrfs_path *path,
24 				      const struct free_space_extent * const extents,
25 				      unsigned int num_extents)
26 {
27 	struct btrfs_free_space_info *info;
28 	struct btrfs_key key;
29 	int prev_bit = 0, bit;
30 	u64 extent_start = 0, offset, end;
31 	u32 flags, extent_count;
32 	unsigned int i;
33 	int ret;
34 
35 	info = search_free_space_info(trans, cache, path, 0);
36 	if (IS_ERR(info)) {
37 		test_err("could not find free space info");
38 		ret = PTR_ERR(info);
39 		goto out;
40 	}
41 	flags = btrfs_free_space_flags(path->nodes[0], info);
42 	extent_count = btrfs_free_space_extent_count(path->nodes[0], info);
43 
44 	if (extent_count != num_extents) {
45 		test_err("extent count is wrong");
46 		ret = -EINVAL;
47 		goto out;
48 	}
49 	if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) {
50 		if (path->slots[0] != 0)
51 			goto invalid;
52 		end = cache->start + cache->length;
53 		i = 0;
54 		while (++path->slots[0] < btrfs_header_nritems(path->nodes[0])) {
55 			btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
56 			if (key.type != BTRFS_FREE_SPACE_BITMAP_KEY)
57 				goto invalid;
58 			offset = key.objectid;
59 			while (offset < key.objectid + key.offset) {
60 				bit = free_space_test_bit(cache, path, offset);
61 				if (prev_bit == 0 && bit == 1) {
62 					extent_start = offset;
63 				} else if (prev_bit == 1 && bit == 0) {
64 					if (i >= num_extents ||
65 					    extent_start != extents[i].start ||
66 					    offset - extent_start != extents[i].length)
67 						goto invalid;
68 					i++;
69 				}
70 				prev_bit = bit;
71 				offset += fs_info->sectorsize;
72 			}
73 		}
74 		if (prev_bit == 1) {
75 			if (i >= num_extents ||
76 			    extent_start != extents[i].start ||
77 			    end - extent_start != extents[i].length)
78 				goto invalid;
79 			i++;
80 		}
81 		if (i != num_extents)
82 			goto invalid;
83 	} else {
84 		if (btrfs_header_nritems(path->nodes[0]) != num_extents + 1 ||
85 		    path->slots[0] != 0)
86 			goto invalid;
87 		for (i = 0; i < num_extents; i++) {
88 			path->slots[0]++;
89 			btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
90 			if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY ||
91 			    key.objectid != extents[i].start ||
92 			    key.offset != extents[i].length)
93 				goto invalid;
94 		}
95 	}
96 
97 	ret = 0;
98 out:
99 	btrfs_release_path(path);
100 	return ret;
101 invalid:
102 	test_err("free space tree is invalid");
103 	ret = -EINVAL;
104 	goto out;
105 }
106 
107 static int check_free_space_extents(struct btrfs_trans_handle *trans,
108 				    struct btrfs_fs_info *fs_info,
109 				    struct btrfs_block_group *cache,
110 				    struct btrfs_path *path,
111 				    const struct free_space_extent * const extents,
112 				    unsigned int num_extents)
113 {
114 	struct btrfs_free_space_info *info;
115 	u32 flags;
116 	int ret;
117 
118 	info = search_free_space_info(trans, cache, path, 0);
119 	if (IS_ERR(info)) {
120 		test_err("could not find free space info");
121 		btrfs_release_path(path);
122 		return PTR_ERR(info);
123 	}
124 	flags = btrfs_free_space_flags(path->nodes[0], info);
125 	btrfs_release_path(path);
126 
127 	ret = __check_free_space_extents(trans, fs_info, cache, path, extents,
128 					 num_extents);
129 	if (ret)
130 		return ret;
131 
132 	/* Flip it to the other format and check that for good measure. */
133 	if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) {
134 		ret = convert_free_space_to_extents(trans, cache, path);
135 		if (ret) {
136 			test_err("could not convert to extents");
137 			return ret;
138 		}
139 	} else {
140 		ret = convert_free_space_to_bitmaps(trans, cache, path);
141 		if (ret) {
142 			test_err("could not convert to bitmaps");
143 			return ret;
144 		}
145 	}
146 	return __check_free_space_extents(trans, fs_info, cache, path, extents,
147 					  num_extents);
148 }
149 
150 static int test_empty_block_group(struct btrfs_trans_handle *trans,
151 				  struct btrfs_fs_info *fs_info,
152 				  struct btrfs_block_group *cache,
153 				  struct btrfs_path *path,
154 				  u32 alignment)
155 {
156 	const struct free_space_extent extents[] = {
157 		{cache->start, cache->length},
158 	};
159 
160 	return check_free_space_extents(trans, fs_info, cache, path,
161 					extents, ARRAY_SIZE(extents));
162 }
163 
164 static int test_remove_all(struct btrfs_trans_handle *trans,
165 			   struct btrfs_fs_info *fs_info,
166 			   struct btrfs_block_group *cache,
167 			   struct btrfs_path *path,
168 			   u32 alignment)
169 {
170 	const struct free_space_extent extents[] = {};
171 	int ret;
172 
173 	ret = __remove_from_free_space_tree(trans, cache, path,
174 					    cache->start,
175 					    cache->length);
176 	if (ret) {
177 		test_err("could not remove free space");
178 		return ret;
179 	}
180 
181 	return check_free_space_extents(trans, fs_info, cache, path,
182 					extents, ARRAY_SIZE(extents));
183 }
184 
185 static int test_remove_beginning(struct btrfs_trans_handle *trans,
186 				 struct btrfs_fs_info *fs_info,
187 				 struct btrfs_block_group *cache,
188 				 struct btrfs_path *path,
189 				 u32 alignment)
190 {
191 	const struct free_space_extent extents[] = {
192 		{cache->start + alignment, cache->length - alignment},
193 	};
194 	int ret;
195 
196 	ret = __remove_from_free_space_tree(trans, cache, path,
197 					    cache->start, alignment);
198 	if (ret) {
199 		test_err("could not remove free space");
200 		return ret;
201 	}
202 
203 	return check_free_space_extents(trans, fs_info, cache, path,
204 					extents, ARRAY_SIZE(extents));
205 
206 }
207 
208 static int test_remove_end(struct btrfs_trans_handle *trans,
209 			   struct btrfs_fs_info *fs_info,
210 			   struct btrfs_block_group *cache,
211 			   struct btrfs_path *path,
212 			   u32 alignment)
213 {
214 	const struct free_space_extent extents[] = {
215 		{cache->start, cache->length - alignment},
216 	};
217 	int ret;
218 
219 	ret = __remove_from_free_space_tree(trans, cache, path,
220 				    cache->start + cache->length - alignment,
221 				    alignment);
222 	if (ret) {
223 		test_err("could not remove free space");
224 		return ret;
225 	}
226 
227 	return check_free_space_extents(trans, fs_info, cache, path,
228 					extents, ARRAY_SIZE(extents));
229 }
230 
231 static int test_remove_middle(struct btrfs_trans_handle *trans,
232 			      struct btrfs_fs_info *fs_info,
233 			      struct btrfs_block_group *cache,
234 			      struct btrfs_path *path,
235 			      u32 alignment)
236 {
237 	const struct free_space_extent extents[] = {
238 		{cache->start, alignment},
239 		{cache->start + 2 * alignment, cache->length - 2 * alignment},
240 	};
241 	int ret;
242 
243 	ret = __remove_from_free_space_tree(trans, cache, path,
244 					    cache->start + alignment,
245 					    alignment);
246 	if (ret) {
247 		test_err("could not remove free space");
248 		return ret;
249 	}
250 
251 	return check_free_space_extents(trans, fs_info, cache, path,
252 					extents, ARRAY_SIZE(extents));
253 }
254 
255 static int test_merge_left(struct btrfs_trans_handle *trans,
256 			   struct btrfs_fs_info *fs_info,
257 			   struct btrfs_block_group *cache,
258 			   struct btrfs_path *path,
259 			   u32 alignment)
260 {
261 	const struct free_space_extent extents[] = {
262 		{cache->start, 2 * alignment},
263 	};
264 	int ret;
265 
266 	ret = __remove_from_free_space_tree(trans, cache, path,
267 					    cache->start, cache->length);
268 	if (ret) {
269 		test_err("could not remove free space");
270 		return ret;
271 	}
272 
273 	ret = __add_to_free_space_tree(trans, cache, path, cache->start,
274 				       alignment);
275 	if (ret) {
276 		test_err("could not add free space");
277 		return ret;
278 	}
279 
280 	ret = __add_to_free_space_tree(trans, cache, path,
281 				       cache->start + alignment,
282 				       alignment);
283 	if (ret) {
284 		test_err("could not add free space");
285 		return ret;
286 	}
287 
288 	return check_free_space_extents(trans, fs_info, cache, path,
289 					extents, ARRAY_SIZE(extents));
290 }
291 
292 static int test_merge_right(struct btrfs_trans_handle *trans,
293 			   struct btrfs_fs_info *fs_info,
294 			   struct btrfs_block_group *cache,
295 			   struct btrfs_path *path,
296 			   u32 alignment)
297 {
298 	const struct free_space_extent extents[] = {
299 		{cache->start + alignment, 2 * alignment},
300 	};
301 	int ret;
302 
303 	ret = __remove_from_free_space_tree(trans, cache, path,
304 					    cache->start, cache->length);
305 	if (ret) {
306 		test_err("could not remove free space");
307 		return ret;
308 	}
309 
310 	ret = __add_to_free_space_tree(trans, cache, path,
311 				       cache->start + 2 * alignment,
312 				       alignment);
313 	if (ret) {
314 		test_err("could not add free space");
315 		return ret;
316 	}
317 
318 	ret = __add_to_free_space_tree(trans, cache, path,
319 				       cache->start + alignment,
320 				       alignment);
321 	if (ret) {
322 		test_err("could not add free space");
323 		return ret;
324 	}
325 
326 	return check_free_space_extents(trans, fs_info, cache, path,
327 					extents, ARRAY_SIZE(extents));
328 }
329 
330 static int test_merge_both(struct btrfs_trans_handle *trans,
331 			   struct btrfs_fs_info *fs_info,
332 			   struct btrfs_block_group *cache,
333 			   struct btrfs_path *path,
334 			   u32 alignment)
335 {
336 	const struct free_space_extent extents[] = {
337 		{cache->start, 3 * alignment},
338 	};
339 	int ret;
340 
341 	ret = __remove_from_free_space_tree(trans, cache, path,
342 					    cache->start, cache->length);
343 	if (ret) {
344 		test_err("could not remove free space");
345 		return ret;
346 	}
347 
348 	ret = __add_to_free_space_tree(trans, cache, path, cache->start,
349 				       alignment);
350 	if (ret) {
351 		test_err("could not add free space");
352 		return ret;
353 	}
354 
355 	ret = __add_to_free_space_tree(trans, cache, path,
356 				       cache->start + 2 * alignment, alignment);
357 	if (ret) {
358 		test_err("could not add free space");
359 		return ret;
360 	}
361 
362 	ret = __add_to_free_space_tree(trans, cache, path,
363 				       cache->start + alignment, alignment);
364 	if (ret) {
365 		test_err("could not add free space");
366 		return ret;
367 	}
368 
369 	return check_free_space_extents(trans, fs_info, cache, path,
370 					extents, ARRAY_SIZE(extents));
371 }
372 
373 static int test_merge_none(struct btrfs_trans_handle *trans,
374 			   struct btrfs_fs_info *fs_info,
375 			   struct btrfs_block_group *cache,
376 			   struct btrfs_path *path,
377 			   u32 alignment)
378 {
379 	const struct free_space_extent extents[] = {
380 		{cache->start, alignment},
381 		{cache->start + 2 * alignment, alignment},
382 		{cache->start + 4 * alignment, alignment},
383 	};
384 	int ret;
385 
386 	ret = __remove_from_free_space_tree(trans, cache, path,
387 					    cache->start, cache->length);
388 	if (ret) {
389 		test_err("could not remove free space");
390 		return ret;
391 	}
392 
393 	ret = __add_to_free_space_tree(trans, cache, path, cache->start,
394 				       alignment);
395 	if (ret) {
396 		test_err("could not add free space");
397 		return ret;
398 	}
399 
400 	ret = __add_to_free_space_tree(trans, cache, path,
401 				       cache->start + 4 * alignment, alignment);
402 	if (ret) {
403 		test_err("could not add free space");
404 		return ret;
405 	}
406 
407 	ret = __add_to_free_space_tree(trans, cache, path,
408 				       cache->start + 2 * alignment, alignment);
409 	if (ret) {
410 		test_err("could not add free space");
411 		return ret;
412 	}
413 
414 	return check_free_space_extents(trans, fs_info, cache, path,
415 					extents, ARRAY_SIZE(extents));
416 }
417 
418 typedef int (*test_func_t)(struct btrfs_trans_handle *,
419 			   struct btrfs_fs_info *,
420 			   struct btrfs_block_group *,
421 			   struct btrfs_path *,
422 			   u32 alignment);
423 
424 static int run_test(test_func_t test_func, int bitmaps, u32 sectorsize,
425 		    u32 nodesize, u32 alignment)
426 {
427 	struct btrfs_fs_info *fs_info;
428 	struct btrfs_root *root = NULL;
429 	struct btrfs_block_group *cache = NULL;
430 	struct btrfs_trans_handle trans;
431 	struct btrfs_path *path = NULL;
432 	int ret;
433 
434 	fs_info = btrfs_alloc_dummy_fs_info(nodesize, sectorsize);
435 	if (!fs_info) {
436 		test_std_err(TEST_ALLOC_FS_INFO);
437 		ret = -ENOMEM;
438 		goto out;
439 	}
440 
441 	root = btrfs_alloc_dummy_root(fs_info);
442 	if (IS_ERR(root)) {
443 		test_std_err(TEST_ALLOC_ROOT);
444 		ret = PTR_ERR(root);
445 		goto out;
446 	}
447 
448 	btrfs_set_super_compat_ro_flags(root->fs_info->super_copy,
449 					BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE);
450 	root->root_key.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID;
451 	root->root_key.type = BTRFS_ROOT_ITEM_KEY;
452 	root->root_key.offset = 0;
453 	btrfs_global_root_insert(root);
454 	root->fs_info->tree_root = root;
455 
456 	root->node = alloc_test_extent_buffer(root->fs_info, nodesize);
457 	if (IS_ERR(root->node)) {
458 		test_std_err(TEST_ALLOC_EXTENT_BUFFER);
459 		ret = PTR_ERR(root->node);
460 		goto out;
461 	}
462 	btrfs_set_header_level(root->node, 0);
463 	btrfs_set_header_nritems(root->node, 0);
464 	root->alloc_bytenr += 2 * nodesize;
465 
466 	cache = btrfs_alloc_dummy_block_group(fs_info, 8 * alignment);
467 	if (!cache) {
468 		test_std_err(TEST_ALLOC_BLOCK_GROUP);
469 		ret = -ENOMEM;
470 		goto out;
471 	}
472 	cache->bitmap_low_thresh = 0;
473 	cache->bitmap_high_thresh = (u32)-1;
474 	set_bit(BLOCK_GROUP_FLAG_NEEDS_FREE_SPACE, &cache->runtime_flags);
475 	cache->fs_info = root->fs_info;
476 
477 	btrfs_init_dummy_trans(&trans, root->fs_info);
478 
479 	path = btrfs_alloc_path();
480 	if (!path) {
481 		test_std_err(TEST_ALLOC_ROOT);
482 		ret = -ENOMEM;
483 		goto out;
484 	}
485 
486 	ret = add_block_group_free_space(&trans, cache);
487 	if (ret) {
488 		test_err("could not add block group free space");
489 		goto out;
490 	}
491 
492 	if (bitmaps) {
493 		ret = convert_free_space_to_bitmaps(&trans, cache, path);
494 		if (ret) {
495 			test_err("could not convert block group to bitmaps");
496 			goto out;
497 		}
498 	}
499 
500 	ret = test_func(&trans, root->fs_info, cache, path, alignment);
501 	if (ret)
502 		goto out;
503 
504 	ret = remove_block_group_free_space(&trans, cache);
505 	if (ret) {
506 		test_err("could not remove block group free space");
507 		goto out;
508 	}
509 
510 	if (btrfs_header_nritems(root->node) != 0) {
511 		test_err("free space tree has leftover items");
512 		ret = -EINVAL;
513 		goto out;
514 	}
515 
516 	ret = 0;
517 out:
518 	btrfs_free_path(path);
519 	btrfs_free_dummy_block_group(cache);
520 	btrfs_free_dummy_root(root);
521 	btrfs_free_dummy_fs_info(fs_info);
522 	return ret;
523 }
524 
525 static int run_test_both_formats(test_func_t test_func, u32 sectorsize,
526 				 u32 nodesize, u32 alignment)
527 {
528 	int test_ret = 0;
529 	int ret;
530 
531 	ret = run_test(test_func, 0, sectorsize, nodesize, alignment);
532 	if (ret) {
533 		test_err(
534 	"%ps failed with extents, sectorsize=%u, nodesize=%u, alignment=%u",
535 			 test_func, sectorsize, nodesize, alignment);
536 		test_ret = ret;
537 	}
538 
539 	ret = run_test(test_func, 1, sectorsize, nodesize, alignment);
540 	if (ret) {
541 		test_err(
542 	"%ps failed with bitmaps, sectorsize=%u, nodesize=%u, alignment=%u",
543 			 test_func, sectorsize, nodesize, alignment);
544 		test_ret = ret;
545 	}
546 
547 	return test_ret;
548 }
549 
550 int btrfs_test_free_space_tree(u32 sectorsize, u32 nodesize)
551 {
552 	test_func_t tests[] = {
553 		test_empty_block_group,
554 		test_remove_all,
555 		test_remove_beginning,
556 		test_remove_end,
557 		test_remove_middle,
558 		test_merge_left,
559 		test_merge_right,
560 		test_merge_both,
561 		test_merge_none,
562 	};
563 	u32 bitmap_alignment;
564 	int test_ret = 0;
565 	int i;
566 
567 	/*
568 	 * Align some operations to a page to flush out bugs in the extent
569 	 * buffer bitmap handling of highmem.
570 	 */
571 	bitmap_alignment = BTRFS_FREE_SPACE_BITMAP_BITS * PAGE_SIZE;
572 
573 	test_msg("running free space tree tests");
574 	for (i = 0; i < ARRAY_SIZE(tests); i++) {
575 		int ret;
576 
577 		ret = run_test_both_formats(tests[i], sectorsize, nodesize,
578 					    sectorsize);
579 		if (ret)
580 			test_ret = ret;
581 
582 		ret = run_test_both_formats(tests[i], sectorsize, nodesize,
583 					    bitmap_alignment);
584 		if (ret)
585 			test_ret = ret;
586 	}
587 
588 	return test_ret;
589 }
590