Linux 6.10-rc4
[sfrench/cifs-2.6.git] / fs / ext4 / mballoc-test.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * KUnit test of ext4 multiblocks allocation.
4  */
5
6 #include <kunit/test.h>
7 #include <kunit/static_stub.h>
8 #include <linux/random.h>
9
10 #include "ext4.h"
11
12 struct mbt_grp_ctx {
13         struct buffer_head bitmap_bh;
14         /* desc and gd_bh are just the place holders for now */
15         struct ext4_group_desc desc;
16         struct buffer_head gd_bh;
17 };
18
19 struct mbt_ctx {
20         struct mbt_grp_ctx *grp_ctx;
21 };
22
23 struct mbt_ext4_super_block {
24         struct ext4_super_block es;
25         struct ext4_sb_info sbi;
26         struct mbt_ctx mbt_ctx;
27 };
28
29 #define MBT_SB(_sb) (container_of((_sb)->s_fs_info, struct mbt_ext4_super_block, sbi))
30 #define MBT_CTX(_sb) (&MBT_SB(_sb)->mbt_ctx)
31 #define MBT_GRP_CTX(_sb, _group) (&MBT_CTX(_sb)->grp_ctx[_group])
32
33 static struct inode *mbt_alloc_inode(struct super_block *sb)
34 {
35         struct ext4_inode_info *ei;
36
37         ei = kmalloc(sizeof(struct ext4_inode_info), GFP_KERNEL);
38         if (!ei)
39                 return NULL;
40
41         INIT_LIST_HEAD(&ei->i_orphan);
42         init_rwsem(&ei->xattr_sem);
43         init_rwsem(&ei->i_data_sem);
44         inode_init_once(&ei->vfs_inode);
45         ext4_fc_init_inode(&ei->vfs_inode);
46
47         return &ei->vfs_inode;
48 }
49
50 static void mbt_free_inode(struct inode *inode)
51 {
52         kfree(EXT4_I(inode));
53 }
54
55 static const struct super_operations mbt_sops = {
56         .alloc_inode    = mbt_alloc_inode,
57         .free_inode     = mbt_free_inode,
58 };
59
60 static void mbt_kill_sb(struct super_block *sb)
61 {
62         generic_shutdown_super(sb);
63 }
64
65 static struct file_system_type mbt_fs_type = {
66         .name                   = "mballoc test",
67         .kill_sb                = mbt_kill_sb,
68 };
69
70 static int mbt_mb_init(struct super_block *sb)
71 {
72         ext4_fsblk_t block;
73         int ret;
74
75         /* needed by ext4_mb_init->bdev_nonrot(sb->s_bdev) */
76         sb->s_bdev = kzalloc(sizeof(*sb->s_bdev), GFP_KERNEL);
77         if (sb->s_bdev == NULL)
78                 return -ENOMEM;
79
80         sb->s_bdev->bd_queue = kzalloc(sizeof(struct request_queue), GFP_KERNEL);
81         if (sb->s_bdev->bd_queue == NULL) {
82                 kfree(sb->s_bdev);
83                 return -ENOMEM;
84         }
85
86         /*
87          * needed by ext4_mb_init->ext4_mb_init_backend-> sbi->s_buddy_cache =
88          * new_inode(sb);
89          */
90         INIT_LIST_HEAD(&sb->s_inodes);
91         sb->s_op = &mbt_sops;
92
93         ret = ext4_mb_init(sb);
94         if (ret != 0)
95                 goto err_out;
96
97         block = ext4_count_free_clusters(sb);
98         ret = percpu_counter_init(&EXT4_SB(sb)->s_freeclusters_counter, block,
99                                   GFP_KERNEL);
100         if (ret != 0)
101                 goto err_mb_release;
102
103         ret = percpu_counter_init(&EXT4_SB(sb)->s_dirtyclusters_counter, 0,
104                                   GFP_KERNEL);
105         if (ret != 0)
106                 goto err_freeclusters;
107
108         return 0;
109
110 err_freeclusters:
111         percpu_counter_destroy(&EXT4_SB(sb)->s_freeclusters_counter);
112 err_mb_release:
113         ext4_mb_release(sb);
114 err_out:
115         kfree(sb->s_bdev->bd_queue);
116         kfree(sb->s_bdev);
117         return ret;
118 }
119
120 static void mbt_mb_release(struct super_block *sb)
121 {
122         percpu_counter_destroy(&EXT4_SB(sb)->s_dirtyclusters_counter);
123         percpu_counter_destroy(&EXT4_SB(sb)->s_freeclusters_counter);
124         ext4_mb_release(sb);
125         kfree(sb->s_bdev->bd_queue);
126         kfree(sb->s_bdev);
127 }
128
129 static int mbt_set(struct super_block *sb, void *data)
130 {
131         return 0;
132 }
133
134 static struct super_block *mbt_ext4_alloc_super_block(void)
135 {
136         struct mbt_ext4_super_block *fsb;
137         struct super_block *sb;
138         struct ext4_sb_info *sbi;
139
140         fsb = kzalloc(sizeof(*fsb), GFP_KERNEL);
141         if (fsb == NULL)
142                 return NULL;
143
144         sb = sget(&mbt_fs_type, NULL, mbt_set, 0, NULL);
145         if (IS_ERR(sb))
146                 goto out;
147
148         sbi = &fsb->sbi;
149
150         sbi->s_blockgroup_lock =
151                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
152         if (!sbi->s_blockgroup_lock)
153                 goto out_deactivate;
154
155         bgl_lock_init(sbi->s_blockgroup_lock);
156
157         sbi->s_es = &fsb->es;
158         sb->s_fs_info = sbi;
159
160         up_write(&sb->s_umount);
161         return sb;
162
163 out_deactivate:
164         deactivate_locked_super(sb);
165 out:
166         kfree(fsb);
167         return NULL;
168 }
169
170 static void mbt_ext4_free_super_block(struct super_block *sb)
171 {
172         struct mbt_ext4_super_block *fsb = MBT_SB(sb);
173         struct ext4_sb_info *sbi = EXT4_SB(sb);
174
175         kfree(sbi->s_blockgroup_lock);
176         deactivate_super(sb);
177         kfree(fsb);
178 }
179
180 struct mbt_ext4_block_layout {
181         unsigned char blocksize_bits;
182         unsigned int cluster_bits;
183         uint32_t blocks_per_group;
184         ext4_group_t group_count;
185         uint16_t desc_size;
186 };
187
188 static void mbt_init_sb_layout(struct super_block *sb,
189                                struct mbt_ext4_block_layout *layout)
190 {
191         struct ext4_sb_info *sbi = EXT4_SB(sb);
192         struct ext4_super_block *es = sbi->s_es;
193
194         sb->s_blocksize = 1UL << layout->blocksize_bits;
195         sb->s_blocksize_bits = layout->blocksize_bits;
196
197         sbi->s_groups_count = layout->group_count;
198         sbi->s_blocks_per_group = layout->blocks_per_group;
199         sbi->s_cluster_bits = layout->cluster_bits;
200         sbi->s_cluster_ratio = 1U << layout->cluster_bits;
201         sbi->s_clusters_per_group = layout->blocks_per_group >>
202                                     layout->cluster_bits;
203         sbi->s_desc_size = layout->desc_size;
204         sbi->s_desc_per_block_bits =
205                 sb->s_blocksize_bits - (fls(layout->desc_size) - 1);
206         sbi->s_desc_per_block = 1 << sbi->s_desc_per_block_bits;
207
208         es->s_first_data_block = cpu_to_le32(0);
209         es->s_blocks_count_lo = cpu_to_le32(layout->blocks_per_group *
210                                             layout->group_count);
211 }
212
213 static int mbt_grp_ctx_init(struct super_block *sb,
214                             struct mbt_grp_ctx *grp_ctx)
215 {
216         ext4_grpblk_t max = EXT4_CLUSTERS_PER_GROUP(sb);
217
218         grp_ctx->bitmap_bh.b_data = kzalloc(EXT4_BLOCK_SIZE(sb), GFP_KERNEL);
219         if (grp_ctx->bitmap_bh.b_data == NULL)
220                 return -ENOMEM;
221         mb_set_bits(grp_ctx->bitmap_bh.b_data, max, sb->s_blocksize * 8 - max);
222         ext4_free_group_clusters_set(sb, &grp_ctx->desc, max);
223
224         return 0;
225 }
226
227 static void mbt_grp_ctx_release(struct mbt_grp_ctx *grp_ctx)
228 {
229         kfree(grp_ctx->bitmap_bh.b_data);
230         grp_ctx->bitmap_bh.b_data = NULL;
231 }
232
233 static void mbt_ctx_mark_used(struct super_block *sb, ext4_group_t group,
234                               unsigned int start, unsigned int len)
235 {
236         struct mbt_grp_ctx *grp_ctx = MBT_GRP_CTX(sb, group);
237
238         mb_set_bits(grp_ctx->bitmap_bh.b_data, start, len);
239 }
240
241 static void *mbt_ctx_bitmap(struct super_block *sb, ext4_group_t group)
242 {
243         struct mbt_grp_ctx *grp_ctx = MBT_GRP_CTX(sb, group);
244
245         return grp_ctx->bitmap_bh.b_data;
246 }
247
248 /* called after mbt_init_sb_layout */
249 static int mbt_ctx_init(struct super_block *sb)
250 {
251         struct mbt_ctx *ctx = MBT_CTX(sb);
252         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
253
254         ctx->grp_ctx = kcalloc(ngroups, sizeof(struct mbt_grp_ctx),
255                                GFP_KERNEL);
256         if (ctx->grp_ctx == NULL)
257                 return -ENOMEM;
258
259         for (i = 0; i < ngroups; i++)
260                 if (mbt_grp_ctx_init(sb, &ctx->grp_ctx[i]))
261                         goto out;
262
263         /*
264          * first data block(first cluster in first group) is used by
265          * metadata, mark it used to avoid to alloc data block at first
266          * block which will fail ext4_sb_block_valid check.
267          */
268         mb_set_bits(ctx->grp_ctx[0].bitmap_bh.b_data, 0, 1);
269         ext4_free_group_clusters_set(sb, &ctx->grp_ctx[0].desc,
270                                      EXT4_CLUSTERS_PER_GROUP(sb) - 1);
271
272         return 0;
273 out:
274         while (i-- > 0)
275                 mbt_grp_ctx_release(&ctx->grp_ctx[i]);
276         kfree(ctx->grp_ctx);
277         return -ENOMEM;
278 }
279
280 static void mbt_ctx_release(struct super_block *sb)
281 {
282         struct mbt_ctx *ctx = MBT_CTX(sb);
283         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
284
285         for (i = 0; i < ngroups; i++)
286                 mbt_grp_ctx_release(&ctx->grp_ctx[i]);
287         kfree(ctx->grp_ctx);
288 }
289
290 static struct buffer_head *
291 ext4_read_block_bitmap_nowait_stub(struct super_block *sb, ext4_group_t block_group,
292                                    bool ignore_locked)
293 {
294         struct mbt_grp_ctx *grp_ctx = MBT_GRP_CTX(sb, block_group);
295
296         /* paired with brelse from caller of ext4_read_block_bitmap_nowait */
297         get_bh(&grp_ctx->bitmap_bh);
298         return &grp_ctx->bitmap_bh;
299 }
300
301 static int ext4_wait_block_bitmap_stub(struct super_block *sb,
302                                        ext4_group_t block_group,
303                                        struct buffer_head *bh)
304 {
305         /*
306          * real ext4_wait_block_bitmap will set these flags and
307          * functions like ext4_mb_init_cache will verify the flags.
308          */
309         set_buffer_uptodate(bh);
310         set_bitmap_uptodate(bh);
311         set_buffer_verified(bh);
312         return 0;
313 }
314
315 static struct ext4_group_desc *
316 ext4_get_group_desc_stub(struct super_block *sb, ext4_group_t block_group,
317                          struct buffer_head **bh)
318 {
319         struct mbt_grp_ctx *grp_ctx = MBT_GRP_CTX(sb, block_group);
320
321         if (bh != NULL)
322                 *bh = &grp_ctx->gd_bh;
323
324         return &grp_ctx->desc;
325 }
326
327 static int
328 ext4_mb_mark_context_stub(handle_t *handle, struct super_block *sb, bool state,
329                           ext4_group_t group, ext4_grpblk_t blkoff,
330                           ext4_grpblk_t len, int flags,
331                           ext4_grpblk_t *ret_changed)
332 {
333         struct mbt_grp_ctx *grp_ctx = MBT_GRP_CTX(sb, group);
334         struct buffer_head *bitmap_bh = &grp_ctx->bitmap_bh;
335
336         if (state)
337                 mb_set_bits(bitmap_bh->b_data, blkoff, len);
338         else
339                 mb_clear_bits(bitmap_bh->b_data, blkoff, len);
340
341         return 0;
342 }
343
344 #define TEST_GOAL_GROUP 1
345 static int mbt_kunit_init(struct kunit *test)
346 {
347         struct mbt_ext4_block_layout *layout =
348                 (struct mbt_ext4_block_layout *)(test->param_value);
349         struct super_block *sb;
350         int ret;
351
352         sb = mbt_ext4_alloc_super_block();
353         if (sb == NULL)
354                 return -ENOMEM;
355
356         mbt_init_sb_layout(sb, layout);
357
358         ret = mbt_ctx_init(sb);
359         if (ret != 0) {
360                 mbt_ext4_free_super_block(sb);
361                 return ret;
362         }
363
364         test->priv = sb;
365         kunit_activate_static_stub(test,
366                                    ext4_read_block_bitmap_nowait,
367                                    ext4_read_block_bitmap_nowait_stub);
368         kunit_activate_static_stub(test,
369                                    ext4_wait_block_bitmap,
370                                    ext4_wait_block_bitmap_stub);
371         kunit_activate_static_stub(test,
372                                    ext4_get_group_desc,
373                                    ext4_get_group_desc_stub);
374         kunit_activate_static_stub(test,
375                                    ext4_mb_mark_context,
376                                    ext4_mb_mark_context_stub);
377
378         /* stub function will be called in mbt_mb_init->ext4_mb_init */
379         if (mbt_mb_init(sb) != 0) {
380                 mbt_ctx_release(sb);
381                 mbt_ext4_free_super_block(sb);
382                 return -ENOMEM;
383         }
384
385         return 0;
386 }
387
388 static void mbt_kunit_exit(struct kunit *test)
389 {
390         struct super_block *sb = (struct super_block *)test->priv;
391
392         mbt_mb_release(sb);
393         mbt_ctx_release(sb);
394         mbt_ext4_free_super_block(sb);
395 }
396
397 static void test_new_blocks_simple(struct kunit *test)
398 {
399         struct super_block *sb = (struct super_block *)test->priv;
400         struct inode *inode;
401         struct ext4_allocation_request ar;
402         ext4_group_t i, goal_group = TEST_GOAL_GROUP;
403         int err = 0;
404         ext4_fsblk_t found;
405         struct ext4_sb_info *sbi = EXT4_SB(sb);
406
407         inode = kunit_kzalloc(test, sizeof(*inode), GFP_KERNEL);
408         if (!inode)
409                 return;
410
411         inode->i_sb = sb;
412         ar.inode = inode;
413
414         /* get block at goal */
415         ar.goal = ext4_group_first_block_no(sb, goal_group);
416         found = ext4_mb_new_blocks_simple(&ar, &err);
417         KUNIT_ASSERT_EQ_MSG(test, ar.goal, found,
418                 "failed to alloc block at goal, expected %llu found %llu",
419                 ar.goal, found);
420
421         /* get block after goal in goal group */
422         ar.goal = ext4_group_first_block_no(sb, goal_group);
423         found = ext4_mb_new_blocks_simple(&ar, &err);
424         KUNIT_ASSERT_EQ_MSG(test, ar.goal + EXT4_C2B(sbi, 1), found,
425                 "failed to alloc block after goal in goal group, expected %llu found %llu",
426                 ar.goal + 1, found);
427
428         /* get block after goal group */
429         mbt_ctx_mark_used(sb, goal_group, 0, EXT4_CLUSTERS_PER_GROUP(sb));
430         ar.goal = ext4_group_first_block_no(sb, goal_group);
431         found = ext4_mb_new_blocks_simple(&ar, &err);
432         KUNIT_ASSERT_EQ_MSG(test,
433                 ext4_group_first_block_no(sb, goal_group + 1), found,
434                 "failed to alloc block after goal group, expected %llu found %llu",
435                 ext4_group_first_block_no(sb, goal_group + 1), found);
436
437         /* get block before goal group */
438         for (i = goal_group; i < ext4_get_groups_count(sb); i++)
439                 mbt_ctx_mark_used(sb, i, 0, EXT4_CLUSTERS_PER_GROUP(sb));
440         ar.goal = ext4_group_first_block_no(sb, goal_group);
441         found = ext4_mb_new_blocks_simple(&ar, &err);
442         KUNIT_ASSERT_EQ_MSG(test,
443                 ext4_group_first_block_no(sb, 0) + EXT4_C2B(sbi, 1), found,
444                 "failed to alloc block before goal group, expected %llu found %llu",
445                 ext4_group_first_block_no(sb, 0 + EXT4_C2B(sbi, 1)), found);
446
447         /* no block available, fail to allocate block */
448         for (i = 0; i < ext4_get_groups_count(sb); i++)
449                 mbt_ctx_mark_used(sb, i, 0, EXT4_CLUSTERS_PER_GROUP(sb));
450         ar.goal = ext4_group_first_block_no(sb, goal_group);
451         found = ext4_mb_new_blocks_simple(&ar, &err);
452         KUNIT_ASSERT_NE_MSG(test, err, 0,
453                 "unexpectedly get block when no block is available");
454 }
455
456 #define TEST_RANGE_COUNT 8
457
458 struct test_range {
459         ext4_grpblk_t start;
460         ext4_grpblk_t len;
461 };
462
463 static void
464 mbt_generate_test_ranges(struct super_block *sb, struct test_range *ranges,
465                          int count)
466 {
467         ext4_grpblk_t start, len, max;
468         int i;
469
470         max = EXT4_CLUSTERS_PER_GROUP(sb) / count;
471         for (i = 0; i < count; i++) {
472                 start = get_random_u32() % max;
473                 len = get_random_u32() % max;
474                 len = min(len, max - start);
475
476                 ranges[i].start = start + i * max;
477                 ranges[i].len = len;
478         }
479 }
480
481 static void
482 validate_free_blocks_simple(struct kunit *test, struct super_block *sb,
483                             ext4_group_t goal_group, ext4_grpblk_t start,
484                             ext4_grpblk_t len)
485 {
486         void *bitmap;
487         ext4_grpblk_t bit, max = EXT4_CLUSTERS_PER_GROUP(sb);
488         ext4_group_t i;
489
490         for (i = 0; i < ext4_get_groups_count(sb); i++) {
491                 if (i == goal_group)
492                         continue;
493
494                 bitmap = mbt_ctx_bitmap(sb, i);
495                 bit = mb_find_next_zero_bit(bitmap, max, 0);
496                 KUNIT_ASSERT_EQ_MSG(test, bit, max,
497                                     "free block on unexpected group %d", i);
498         }
499
500         bitmap = mbt_ctx_bitmap(sb, goal_group);
501         bit = mb_find_next_zero_bit(bitmap, max, 0);
502         KUNIT_ASSERT_EQ(test, bit, start);
503
504         bit = mb_find_next_bit(bitmap, max, bit + 1);
505         KUNIT_ASSERT_EQ(test, bit, start + len);
506 }
507
508 static void
509 test_free_blocks_simple_range(struct kunit *test, ext4_group_t goal_group,
510                               ext4_grpblk_t start, ext4_grpblk_t len)
511 {
512         struct super_block *sb = (struct super_block *)test->priv;
513         struct ext4_sb_info *sbi = EXT4_SB(sb);
514         struct inode *inode;
515         ext4_fsblk_t block;
516
517         inode = kunit_kzalloc(test, sizeof(*inode), GFP_KERNEL);
518         if (!inode)
519                 return;
520         inode->i_sb = sb;
521
522         if (len == 0)
523                 return;
524
525         block = ext4_group_first_block_no(sb, goal_group) +
526                 EXT4_C2B(sbi, start);
527         ext4_free_blocks_simple(inode, block, len);
528         validate_free_blocks_simple(test, sb, goal_group, start, len);
529         mbt_ctx_mark_used(sb, goal_group, 0, EXT4_CLUSTERS_PER_GROUP(sb));
530 }
531
532 static void test_free_blocks_simple(struct kunit *test)
533 {
534         struct super_block *sb = (struct super_block *)test->priv;
535         ext4_grpblk_t max = EXT4_CLUSTERS_PER_GROUP(sb);
536         ext4_group_t i;
537         struct test_range ranges[TEST_RANGE_COUNT];
538
539         for (i = 0; i < ext4_get_groups_count(sb); i++)
540                 mbt_ctx_mark_used(sb, i, 0, max);
541
542         mbt_generate_test_ranges(sb, ranges, TEST_RANGE_COUNT);
543         for (i = 0; i < TEST_RANGE_COUNT; i++)
544                 test_free_blocks_simple_range(test, TEST_GOAL_GROUP,
545                         ranges[i].start, ranges[i].len);
546 }
547
548 static void
549 test_mark_diskspace_used_range(struct kunit *test,
550                                struct ext4_allocation_context *ac,
551                                ext4_grpblk_t start,
552                                ext4_grpblk_t len)
553 {
554         struct super_block *sb = (struct super_block *)test->priv;
555         int ret;
556         void *bitmap;
557         ext4_grpblk_t i, max;
558
559         /* ext4_mb_mark_diskspace_used will BUG if len is 0 */
560         if (len == 0)
561                 return;
562
563         ac->ac_b_ex.fe_group = TEST_GOAL_GROUP;
564         ac->ac_b_ex.fe_start = start;
565         ac->ac_b_ex.fe_len = len;
566
567         bitmap = mbt_ctx_bitmap(sb, TEST_GOAL_GROUP);
568         memset(bitmap, 0, sb->s_blocksize);
569         ret = ext4_mb_mark_diskspace_used(ac, NULL, 0);
570         KUNIT_ASSERT_EQ(test, ret, 0);
571
572         max = EXT4_CLUSTERS_PER_GROUP(sb);
573         i = mb_find_next_bit(bitmap, max, 0);
574         KUNIT_ASSERT_EQ(test, i, start);
575         i = mb_find_next_zero_bit(bitmap, max, i + 1);
576         KUNIT_ASSERT_EQ(test, i, start + len);
577         i = mb_find_next_bit(bitmap, max, i + 1);
578         KUNIT_ASSERT_EQ(test, max, i);
579 }
580
581 static void test_mark_diskspace_used(struct kunit *test)
582 {
583         struct super_block *sb = (struct super_block *)test->priv;
584         struct inode *inode;
585         struct ext4_allocation_context ac;
586         struct test_range ranges[TEST_RANGE_COUNT];
587         int i;
588
589         mbt_generate_test_ranges(sb, ranges, TEST_RANGE_COUNT);
590
591         inode = kunit_kzalloc(test, sizeof(*inode), GFP_KERNEL);
592         if (!inode)
593                 return;
594         inode->i_sb = sb;
595
596         ac.ac_status = AC_STATUS_FOUND;
597         ac.ac_sb = sb;
598         ac.ac_inode = inode;
599         for (i = 0; i < TEST_RANGE_COUNT; i++)
600                 test_mark_diskspace_used_range(test, &ac, ranges[i].start,
601                                                ranges[i].len);
602 }
603
604 static void mbt_generate_buddy(struct super_block *sb, void *buddy,
605                                void *bitmap, struct ext4_group_info *grp)
606 {
607         struct ext4_sb_info *sbi = EXT4_SB(sb);
608         uint32_t order, off;
609         void *bb, *bb_h;
610         int max;
611
612         memset(buddy, 0xff, sb->s_blocksize);
613         memset(grp, 0, offsetof(struct ext4_group_info,
614                                  bb_counters[MB_NUM_ORDERS(sb)]));
615
616         bb = bitmap;
617         max = EXT4_CLUSTERS_PER_GROUP(sb);
618         bb_h = buddy + sbi->s_mb_offsets[1];
619
620         off = mb_find_next_zero_bit(bb, max, 0);
621         grp->bb_first_free = off;
622         while (off < max) {
623                 grp->bb_counters[0]++;
624                 grp->bb_free++;
625
626                 if (!(off & 1) && !mb_test_bit(off + 1, bb)) {
627                         grp->bb_free++;
628                         grp->bb_counters[0]--;
629                         mb_clear_bit(off >> 1, bb_h);
630                         grp->bb_counters[1]++;
631                         grp->bb_largest_free_order = 1;
632                         off++;
633                 }
634
635                 off = mb_find_next_zero_bit(bb, max, off + 1);
636         }
637
638         for (order = 1; order < MB_NUM_ORDERS(sb) - 1; order++) {
639                 bb = buddy + sbi->s_mb_offsets[order];
640                 bb_h = buddy + sbi->s_mb_offsets[order + 1];
641                 max = max >> 1;
642                 off = mb_find_next_zero_bit(bb, max, 0);
643
644                 while (off < max) {
645                         if (!(off & 1) && !mb_test_bit(off + 1, bb)) {
646                                 mb_set_bits(bb, off, 2);
647                                 grp->bb_counters[order] -= 2;
648                                 mb_clear_bit(off >> 1, bb_h);
649                                 grp->bb_counters[order + 1]++;
650                                 grp->bb_largest_free_order = order + 1;
651                                 off++;
652                         }
653
654                         off = mb_find_next_zero_bit(bb, max, off + 1);
655                 }
656         }
657
658         max = EXT4_CLUSTERS_PER_GROUP(sb);
659         off = mb_find_next_zero_bit(bitmap, max, 0);
660         while (off < max) {
661                 grp->bb_fragments++;
662
663                 off = mb_find_next_bit(bitmap, max, off + 1);
664                 if (off + 1 >= max)
665                         break;
666
667                 off = mb_find_next_zero_bit(bitmap, max, off + 1);
668         }
669 }
670
671 static void
672 mbt_validate_group_info(struct kunit *test, struct ext4_group_info *grp1,
673                         struct ext4_group_info *grp2)
674 {
675         struct super_block *sb = (struct super_block *)test->priv;
676         int i;
677
678         KUNIT_ASSERT_EQ(test, grp1->bb_first_free,
679                         grp2->bb_first_free);
680         KUNIT_ASSERT_EQ(test, grp1->bb_fragments,
681                         grp2->bb_fragments);
682         KUNIT_ASSERT_EQ(test, grp1->bb_free, grp2->bb_free);
683         KUNIT_ASSERT_EQ(test, grp1->bb_largest_free_order,
684                         grp2->bb_largest_free_order);
685
686         for (i = 1; i < MB_NUM_ORDERS(sb); i++) {
687                 KUNIT_ASSERT_EQ_MSG(test, grp1->bb_counters[i],
688                                     grp2->bb_counters[i],
689                                     "bb_counters[%d] diffs, expected %d, generated %d",
690                                     i, grp1->bb_counters[i],
691                                     grp2->bb_counters[i]);
692         }
693 }
694
695 static void
696 do_test_generate_buddy(struct kunit *test, struct super_block *sb, void *bitmap,
697                            void *mbt_buddy, struct ext4_group_info *mbt_grp,
698                            void *ext4_buddy, struct ext4_group_info *ext4_grp)
699 {
700         int i;
701
702         mbt_generate_buddy(sb, mbt_buddy, bitmap, mbt_grp);
703
704         for (i = 0; i < MB_NUM_ORDERS(sb); i++)
705                 ext4_grp->bb_counters[i] = 0;
706         /* needed by validation in ext4_mb_generate_buddy */
707         ext4_grp->bb_free = mbt_grp->bb_free;
708         memset(ext4_buddy, 0xff, sb->s_blocksize);
709         ext4_mb_generate_buddy(sb, ext4_buddy, bitmap, TEST_GOAL_GROUP,
710                                ext4_grp);
711
712         KUNIT_ASSERT_EQ(test, memcmp(mbt_buddy, ext4_buddy, sb->s_blocksize),
713                         0);
714         mbt_validate_group_info(test, mbt_grp, ext4_grp);
715 }
716
717 static void test_mb_generate_buddy(struct kunit *test)
718 {
719         struct super_block *sb = (struct super_block *)test->priv;
720         void *bitmap, *expected_bb, *generate_bb;
721         struct ext4_group_info *expected_grp, *generate_grp;
722         struct test_range ranges[TEST_RANGE_COUNT];
723         int i;
724
725         bitmap = kunit_kzalloc(test, sb->s_blocksize, GFP_KERNEL);
726         KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bitmap);
727         expected_bb = kunit_kzalloc(test, sb->s_blocksize, GFP_KERNEL);
728         KUNIT_ASSERT_NOT_ERR_OR_NULL(test, expected_bb);
729         generate_bb = kunit_kzalloc(test, sb->s_blocksize, GFP_KERNEL);
730         KUNIT_ASSERT_NOT_ERR_OR_NULL(test, generate_bb);
731         expected_grp = kunit_kzalloc(test, offsetof(struct ext4_group_info,
732                                 bb_counters[MB_NUM_ORDERS(sb)]), GFP_KERNEL);
733         KUNIT_ASSERT_NOT_ERR_OR_NULL(test, expected_grp);
734         generate_grp = ext4_get_group_info(sb, TEST_GOAL_GROUP);
735         KUNIT_ASSERT_NOT_NULL(test, generate_grp);
736
737         mbt_generate_test_ranges(sb, ranges, TEST_RANGE_COUNT);
738         for (i = 0; i < TEST_RANGE_COUNT; i++) {
739                 mb_set_bits(bitmap, ranges[i].start, ranges[i].len);
740                 do_test_generate_buddy(test, sb, bitmap, expected_bb,
741                                        expected_grp, generate_bb, generate_grp);
742         }
743 }
744
745 static void
746 test_mb_mark_used_range(struct kunit *test, struct ext4_buddy *e4b,
747                         ext4_grpblk_t start, ext4_grpblk_t len, void *bitmap,
748                         void *buddy, struct ext4_group_info *grp)
749 {
750         struct super_block *sb = (struct super_block *)test->priv;
751         struct ext4_free_extent ex;
752         int i;
753
754         /* mb_mark_used only accepts non-zero len */
755         if (len == 0)
756                 return;
757
758         ex.fe_start = start;
759         ex.fe_len = len;
760         ex.fe_group = TEST_GOAL_GROUP;
761
762         ext4_lock_group(sb, TEST_GOAL_GROUP);
763         mb_mark_used(e4b, &ex);
764         ext4_unlock_group(sb, TEST_GOAL_GROUP);
765
766         mb_set_bits(bitmap, start, len);
767         /* bypass bb_free validatoin in ext4_mb_generate_buddy */
768         grp->bb_free -= len;
769         memset(buddy, 0xff, sb->s_blocksize);
770         for (i = 0; i < MB_NUM_ORDERS(sb); i++)
771                 grp->bb_counters[i] = 0;
772         ext4_mb_generate_buddy(sb, buddy, bitmap, 0, grp);
773
774         KUNIT_ASSERT_EQ(test, memcmp(buddy, e4b->bd_buddy, sb->s_blocksize),
775                         0);
776         mbt_validate_group_info(test, grp, e4b->bd_info);
777 }
778
779 static void test_mb_mark_used(struct kunit *test)
780 {
781         struct ext4_buddy e4b;
782         struct super_block *sb = (struct super_block *)test->priv;
783         void *bitmap, *buddy;
784         struct ext4_group_info *grp;
785         int ret;
786         struct test_range ranges[TEST_RANGE_COUNT];
787         int i;
788
789         /* buddy cache assumes that each page contains at least one block */
790         if (sb->s_blocksize > PAGE_SIZE)
791                 kunit_skip(test, "blocksize exceeds pagesize");
792
793         bitmap = kunit_kzalloc(test, sb->s_blocksize, GFP_KERNEL);
794         KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bitmap);
795         buddy = kunit_kzalloc(test, sb->s_blocksize, GFP_KERNEL);
796         KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buddy);
797         grp = kunit_kzalloc(test, offsetof(struct ext4_group_info,
798                                 bb_counters[MB_NUM_ORDERS(sb)]), GFP_KERNEL);
799
800         ret = ext4_mb_load_buddy(sb, TEST_GOAL_GROUP, &e4b);
801         KUNIT_ASSERT_EQ(test, ret, 0);
802
803         grp->bb_free = EXT4_CLUSTERS_PER_GROUP(sb);
804         mbt_generate_test_ranges(sb, ranges, TEST_RANGE_COUNT);
805         for (i = 0; i < TEST_RANGE_COUNT; i++)
806                 test_mb_mark_used_range(test, &e4b, ranges[i].start,
807                                         ranges[i].len, bitmap, buddy, grp);
808
809         ext4_mb_unload_buddy(&e4b);
810 }
811
812 static void
813 test_mb_free_blocks_range(struct kunit *test, struct ext4_buddy *e4b,
814                           ext4_grpblk_t start, ext4_grpblk_t len, void *bitmap,
815                           void *buddy, struct ext4_group_info *grp)
816 {
817         struct super_block *sb = (struct super_block *)test->priv;
818         int i;
819
820         /* mb_free_blocks will WARN if len is 0 */
821         if (len == 0)
822                 return;
823
824         ext4_lock_group(sb, e4b->bd_group);
825         mb_free_blocks(NULL, e4b, start, len);
826         ext4_unlock_group(sb, e4b->bd_group);
827
828         mb_clear_bits(bitmap, start, len);
829         /* bypass bb_free validatoin in ext4_mb_generate_buddy */
830         grp->bb_free += len;
831         memset(buddy, 0xff, sb->s_blocksize);
832         for (i = 0; i < MB_NUM_ORDERS(sb); i++)
833                 grp->bb_counters[i] = 0;
834         ext4_mb_generate_buddy(sb, buddy, bitmap, 0, grp);
835
836         KUNIT_ASSERT_EQ(test, memcmp(buddy, e4b->bd_buddy, sb->s_blocksize),
837                         0);
838         mbt_validate_group_info(test, grp, e4b->bd_info);
839
840 }
841
842 static void test_mb_free_blocks(struct kunit *test)
843 {
844         struct ext4_buddy e4b;
845         struct super_block *sb = (struct super_block *)test->priv;
846         void *bitmap, *buddy;
847         struct ext4_group_info *grp;
848         struct ext4_free_extent ex;
849         int ret;
850         int i;
851         struct test_range ranges[TEST_RANGE_COUNT];
852
853         /* buddy cache assumes that each page contains at least one block */
854         if (sb->s_blocksize > PAGE_SIZE)
855                 kunit_skip(test, "blocksize exceeds pagesize");
856
857         bitmap = kunit_kzalloc(test, sb->s_blocksize, GFP_KERNEL);
858         KUNIT_ASSERT_NOT_ERR_OR_NULL(test, bitmap);
859         buddy = kunit_kzalloc(test, sb->s_blocksize, GFP_KERNEL);
860         KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buddy);
861         grp = kunit_kzalloc(test, offsetof(struct ext4_group_info,
862                                 bb_counters[MB_NUM_ORDERS(sb)]), GFP_KERNEL);
863
864         ret = ext4_mb_load_buddy(sb, TEST_GOAL_GROUP, &e4b);
865         KUNIT_ASSERT_EQ(test, ret, 0);
866
867         ex.fe_start = 0;
868         ex.fe_len = EXT4_CLUSTERS_PER_GROUP(sb);
869         ex.fe_group = TEST_GOAL_GROUP;
870
871         ext4_lock_group(sb, TEST_GOAL_GROUP);
872         mb_mark_used(&e4b, &ex);
873         ext4_unlock_group(sb, TEST_GOAL_GROUP);
874
875         grp->bb_free = 0;
876         memset(bitmap, 0xff, sb->s_blocksize);
877
878         mbt_generate_test_ranges(sb, ranges, TEST_RANGE_COUNT);
879         for (i = 0; i < TEST_RANGE_COUNT; i++)
880                 test_mb_free_blocks_range(test, &e4b, ranges[i].start,
881                                           ranges[i].len, bitmap, buddy, grp);
882
883         ext4_mb_unload_buddy(&e4b);
884 }
885
886 #define COUNT_FOR_ESTIMATE 100000
887 static void test_mb_mark_used_cost(struct kunit *test)
888 {
889         struct ext4_buddy e4b;
890         struct super_block *sb = (struct super_block *)test->priv;
891         struct ext4_free_extent ex;
892         int ret;
893         struct test_range ranges[TEST_RANGE_COUNT];
894         int i, j;
895         unsigned long start, end, all = 0;
896
897         /* buddy cache assumes that each page contains at least one block */
898         if (sb->s_blocksize > PAGE_SIZE)
899                 kunit_skip(test, "blocksize exceeds pagesize");
900
901         ret = ext4_mb_load_buddy(sb, TEST_GOAL_GROUP, &e4b);
902         KUNIT_ASSERT_EQ(test, ret, 0);
903
904         ex.fe_group = TEST_GOAL_GROUP;
905         for (j = 0; j < COUNT_FOR_ESTIMATE; j++) {
906                 mbt_generate_test_ranges(sb, ranges, TEST_RANGE_COUNT);
907                 start = jiffies;
908                 for (i = 0; i < TEST_RANGE_COUNT; i++) {
909                         if (ranges[i].len == 0)
910                                 continue;
911
912                         ex.fe_start = ranges[i].start;
913                         ex.fe_len = ranges[i].len;
914                         ext4_lock_group(sb, TEST_GOAL_GROUP);
915                         mb_mark_used(&e4b, &ex);
916                         ext4_unlock_group(sb, TEST_GOAL_GROUP);
917                 }
918                 end = jiffies;
919                 all += (end - start);
920
921                 for (i = 0; i < TEST_RANGE_COUNT; i++) {
922                         if (ranges[i].len == 0)
923                                 continue;
924
925                         ext4_lock_group(sb, TEST_GOAL_GROUP);
926                         mb_free_blocks(NULL, &e4b, ranges[i].start,
927                                        ranges[i].len);
928                         ext4_unlock_group(sb, TEST_GOAL_GROUP);
929                 }
930         }
931
932         kunit_info(test, "costed jiffies %lu\n", all);
933         ext4_mb_unload_buddy(&e4b);
934 }
935
936 static const struct mbt_ext4_block_layout mbt_test_layouts[] = {
937         {
938                 .blocksize_bits = 10,
939                 .cluster_bits = 3,
940                 .blocks_per_group = 8192,
941                 .group_count = 4,
942                 .desc_size = 64,
943         },
944         {
945                 .blocksize_bits = 12,
946                 .cluster_bits = 3,
947                 .blocks_per_group = 8192,
948                 .group_count = 4,
949                 .desc_size = 64,
950         },
951         {
952                 .blocksize_bits = 16,
953                 .cluster_bits = 3,
954                 .blocks_per_group = 8192,
955                 .group_count = 4,
956                 .desc_size = 64,
957         },
958 };
959
960 static void mbt_show_layout(const struct mbt_ext4_block_layout *layout,
961                             char *desc)
962 {
963         snprintf(desc, KUNIT_PARAM_DESC_SIZE, "block_bits=%d cluster_bits=%d "
964                  "blocks_per_group=%d group_count=%d desc_size=%d\n",
965                  layout->blocksize_bits, layout->cluster_bits,
966                  layout->blocks_per_group, layout->group_count,
967                  layout->desc_size);
968 }
969 KUNIT_ARRAY_PARAM(mbt_layouts, mbt_test_layouts, mbt_show_layout);
970
971 static struct kunit_case mbt_test_cases[] = {
972         KUNIT_CASE_PARAM(test_new_blocks_simple, mbt_layouts_gen_params),
973         KUNIT_CASE_PARAM(test_free_blocks_simple, mbt_layouts_gen_params),
974         KUNIT_CASE_PARAM(test_mb_generate_buddy, mbt_layouts_gen_params),
975         KUNIT_CASE_PARAM(test_mb_mark_used, mbt_layouts_gen_params),
976         KUNIT_CASE_PARAM(test_mb_free_blocks, mbt_layouts_gen_params),
977         KUNIT_CASE_PARAM(test_mark_diskspace_used, mbt_layouts_gen_params),
978         KUNIT_CASE_PARAM_ATTR(test_mb_mark_used_cost, mbt_layouts_gen_params,
979                               { .speed = KUNIT_SPEED_SLOW }),
980         {}
981 };
982
983 static struct kunit_suite mbt_test_suite = {
984         .name = "ext4_mballoc_test",
985         .init = mbt_kunit_init,
986         .exit = mbt_kunit_exit,
987         .test_cases = mbt_test_cases,
988 };
989
990 kunit_test_suites(&mbt_test_suite);
991
992 MODULE_LICENSE("GPL");