summaryrefslogtreecommitdiff
path: root/fs/ext4/mballoc-test.c
blob: f94901fd38357ea330d39011fcc504cae0a690db (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
// SPDX-License-Identifier: GPL-2.0
/*
 * KUnit test of ext4 multiblocks allocation.
 */

#include <kunit/test.h>
#include <kunit/static_stub.h>

#include "ext4.h"

struct mbt_grp_ctx {
	struct buffer_head bitmap_bh;
	/* desc and gd_bh are just the place holders for now */
	struct ext4_group_desc desc;
	struct buffer_head gd_bh;
};

struct mbt_ctx {
	struct mbt_grp_ctx *grp_ctx;
};

struct mbt_ext4_super_block {
	struct super_block sb;
	struct mbt_ctx mbt_ctx;
};

#define MBT_CTX(_sb) (&(container_of((_sb), struct mbt_ext4_super_block, sb)->mbt_ctx))
#define MBT_GRP_CTX(_sb, _group) (&MBT_CTX(_sb)->grp_ctx[_group])

static struct super_block *mbt_ext4_alloc_super_block(void)
{
	struct ext4_super_block *es = kzalloc(sizeof(*es), GFP_KERNEL);
	struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
	struct mbt_ext4_super_block *fsb = kzalloc(sizeof(*fsb), GFP_KERNEL);

	if (fsb == NULL || sbi == NULL || es == NULL)
		goto out;

	sbi->s_es = es;
	fsb->sb.s_fs_info = sbi;
	return &fsb->sb;

out:
	kfree(fsb);
	kfree(sbi);
	kfree(es);
	return NULL;
}

static void mbt_ext4_free_super_block(struct super_block *sb)
{
	struct mbt_ext4_super_block *fsb =
		container_of(sb, struct mbt_ext4_super_block, sb);
	struct ext4_sb_info *sbi = EXT4_SB(sb);

	kfree(sbi->s_es);
	kfree(sbi);
	kfree(fsb);
}

struct mbt_ext4_block_layout {
	unsigned char blocksize_bits;
	unsigned int cluster_bits;
	uint32_t blocks_per_group;
	ext4_group_t group_count;
	uint16_t desc_size;
};

static void mbt_init_sb_layout(struct super_block *sb,
			       struct mbt_ext4_block_layout *layout)
{
	struct ext4_sb_info *sbi = EXT4_SB(sb);
	struct ext4_super_block *es = sbi->s_es;

	sb->s_blocksize = 1UL << layout->blocksize_bits;
	sb->s_blocksize_bits = layout->blocksize_bits;

	sbi->s_groups_count = layout->group_count;
	sbi->s_blocks_per_group = layout->blocks_per_group;
	sbi->s_cluster_bits = layout->cluster_bits;
	sbi->s_cluster_ratio = 1U << layout->cluster_bits;
	sbi->s_clusters_per_group = layout->blocks_per_group >>
				    layout->cluster_bits;
	sbi->s_desc_size = layout->desc_size;

	es->s_first_data_block = cpu_to_le32(0);
	es->s_blocks_count_lo = cpu_to_le32(layout->blocks_per_group *
					    layout->group_count);
}

static int mbt_grp_ctx_init(struct super_block *sb,
			    struct mbt_grp_ctx *grp_ctx)
{
	grp_ctx->bitmap_bh.b_data = kzalloc(EXT4_BLOCK_SIZE(sb), GFP_KERNEL);
	if (grp_ctx->bitmap_bh.b_data == NULL)
		return -ENOMEM;

	return 0;
}

static void mbt_grp_ctx_release(struct mbt_grp_ctx *grp_ctx)
{
	kfree(grp_ctx->bitmap_bh.b_data);
	grp_ctx->bitmap_bh.b_data = NULL;
}

static void mbt_ctx_mark_used(struct super_block *sb, ext4_group_t group,
			      unsigned int start, unsigned int len)
{
	struct mbt_grp_ctx *grp_ctx = MBT_GRP_CTX(sb, group);

	mb_set_bits(grp_ctx->bitmap_bh.b_data, start, len);
}

/* called after mbt_init_sb_layout */
static int mbt_ctx_init(struct super_block *sb)
{
	struct mbt_ctx *ctx = MBT_CTX(sb);
	ext4_group_t i, ngroups = ext4_get_groups_count(sb);

	ctx->grp_ctx = kcalloc(ngroups, sizeof(struct mbt_grp_ctx),
			       GFP_KERNEL);
	if (ctx->grp_ctx == NULL)
		return -ENOMEM;

	for (i = 0; i < ngroups; i++)
		if (mbt_grp_ctx_init(sb, &ctx->grp_ctx[i]))
			goto out;

	/*
	 * first data block(first cluster in first group) is used by
	 * metadata, mark it used to avoid to alloc data block at first
	 * block which will fail ext4_sb_block_valid check.
	 */
	mb_set_bits(ctx->grp_ctx[0].bitmap_bh.b_data, 0, 1);

	return 0;
out:
	while (i-- > 0)
		mbt_grp_ctx_release(&ctx->grp_ctx[i]);
	kfree(ctx->grp_ctx);
	return -ENOMEM;
}

static void mbt_ctx_release(struct super_block *sb)
{
	struct mbt_ctx *ctx = MBT_CTX(sb);
	ext4_group_t i, ngroups = ext4_get_groups_count(sb);

	for (i = 0; i < ngroups; i++)
		mbt_grp_ctx_release(&ctx->grp_ctx[i]);
	kfree(ctx->grp_ctx);
}

static struct buffer_head *
ext4_read_block_bitmap_nowait_stub(struct super_block *sb, ext4_group_t block_group,
				   bool ignore_locked)
{
	struct mbt_grp_ctx *grp_ctx = MBT_GRP_CTX(sb, block_group);

	/* paired with brelse from caller of ext4_read_block_bitmap_nowait */
	get_bh(&grp_ctx->bitmap_bh);
	return &grp_ctx->bitmap_bh;
}

static int ext4_wait_block_bitmap_stub(struct super_block *sb,
				       ext4_group_t block_group,
				       struct buffer_head *bh)
{
	return 0;
}

static struct ext4_group_desc *
ext4_get_group_desc_stub(struct super_block *sb, ext4_group_t block_group,
			 struct buffer_head **bh)
{
	struct mbt_grp_ctx *grp_ctx = MBT_GRP_CTX(sb, block_group);

	if (bh != NULL)
		*bh = &grp_ctx->gd_bh;

	return &grp_ctx->desc;
}

static int
ext4_mb_mark_context_stub(handle_t *handle, struct super_block *sb, bool state,
			  ext4_group_t group, ext4_grpblk_t blkoff,
			  ext4_grpblk_t len, int flags,
			  ext4_grpblk_t *ret_changed)
{
	struct mbt_grp_ctx *grp_ctx = MBT_GRP_CTX(sb, group);
	struct buffer_head *bitmap_bh = &grp_ctx->bitmap_bh;

	if (state)
		mb_set_bits(bitmap_bh->b_data, blkoff, len);
	else
		mb_clear_bits(bitmap_bh->b_data, blkoff, len);

	return 0;
}

#define TEST_GOAL_GROUP 1
static int mbt_kunit_init(struct kunit *test)
{
	struct mbt_ext4_block_layout *layout =
		(struct mbt_ext4_block_layout *)(test->param_value);
	struct super_block *sb;
	int ret;

	sb = mbt_ext4_alloc_super_block();
	if (sb == NULL)
		return -ENOMEM;

	mbt_init_sb_layout(sb, layout);

	ret = mbt_ctx_init(sb);
	if (ret != 0) {
		mbt_ext4_free_super_block(sb);
		return ret;
	}

	test->priv = sb;
	kunit_activate_static_stub(test,
				   ext4_read_block_bitmap_nowait,
				   ext4_read_block_bitmap_nowait_stub);
	kunit_activate_static_stub(test,
				   ext4_wait_block_bitmap,
				   ext4_wait_block_bitmap_stub);
	kunit_activate_static_stub(test,
				   ext4_get_group_desc,
				   ext4_get_group_desc_stub);
	kunit_activate_static_stub(test,
				   ext4_mb_mark_context,
				   ext4_mb_mark_context_stub);
	return 0;
}

static void mbt_kunit_exit(struct kunit *test)
{
	struct super_block *sb = (struct super_block *)test->priv;

	mbt_ctx_release(sb);
	mbt_ext4_free_super_block(sb);
}

static void test_new_blocks_simple(struct kunit *test)
{
	struct super_block *sb = (struct super_block *)test->priv;
	struct inode inode = { .i_sb = sb, };
	struct ext4_allocation_request ar;
	ext4_group_t i, goal_group = TEST_GOAL_GROUP;
	int err = 0;
	ext4_fsblk_t found;
	struct ext4_sb_info *sbi = EXT4_SB(sb);

	ar.inode = &inode;

	/* get block at goal */
	ar.goal = ext4_group_first_block_no(sb, goal_group);
	found = ext4_mb_new_blocks_simple(&ar, &err);
	KUNIT_ASSERT_EQ_MSG(test, ar.goal, found,
		"failed to alloc block at goal, expected %llu found %llu",
		ar.goal, found);

	/* get block after goal in goal group */
	ar.goal = ext4_group_first_block_no(sb, goal_group);
	found = ext4_mb_new_blocks_simple(&ar, &err);
	KUNIT_ASSERT_EQ_MSG(test, ar.goal + EXT4_C2B(sbi, 1), found,
		"failed to alloc block after goal in goal group, expected %llu found %llu",
		ar.goal + 1, found);

	/* get block after goal group */
	mbt_ctx_mark_used(sb, goal_group, 0, EXT4_CLUSTERS_PER_GROUP(sb));
	ar.goal = ext4_group_first_block_no(sb, goal_group);
	found = ext4_mb_new_blocks_simple(&ar, &err);
	KUNIT_ASSERT_EQ_MSG(test,
		ext4_group_first_block_no(sb, goal_group + 1), found,
		"failed to alloc block after goal group, expected %llu found %llu",
		ext4_group_first_block_no(sb, goal_group + 1), found);

	/* get block before goal group */
	for (i = goal_group; i < ext4_get_groups_count(sb); i++)
		mbt_ctx_mark_used(sb, i, 0, EXT4_CLUSTERS_PER_GROUP(sb));
	ar.goal = ext4_group_first_block_no(sb, goal_group);
	found = ext4_mb_new_blocks_simple(&ar, &err);
	KUNIT_ASSERT_EQ_MSG(test,
		ext4_group_first_block_no(sb, 0) + EXT4_C2B(sbi, 1), found,
		"failed to alloc block before goal group, expected %llu found %llu",
		ext4_group_first_block_no(sb, 0 + EXT4_C2B(sbi, 1)), found);

	/* no block available, fail to allocate block */
	for (i = 0; i < ext4_get_groups_count(sb); i++)
		mbt_ctx_mark_used(sb, i, 0, EXT4_CLUSTERS_PER_GROUP(sb));
	ar.goal = ext4_group_first_block_no(sb, goal_group);
	found = ext4_mb_new_blocks_simple(&ar, &err);
	KUNIT_ASSERT_NE_MSG(test, err, 0,
		"unexpectedly get block when no block is available");
}

static const struct mbt_ext4_block_layout mbt_test_layouts[] = {
	{
		.blocksize_bits = 10,
		.cluster_bits = 3,
		.blocks_per_group = 8192,
		.group_count = 4,
		.desc_size = 64,
	},
	{
		.blocksize_bits = 12,
		.cluster_bits = 3,
		.blocks_per_group = 8192,
		.group_count = 4,
		.desc_size = 64,
	},
	{
		.blocksize_bits = 16,
		.cluster_bits = 3,
		.blocks_per_group = 8192,
		.group_count = 4,
		.desc_size = 64,
	},
};

static void mbt_show_layout(const struct mbt_ext4_block_layout *layout,
			    char *desc)
{
	snprintf(desc, KUNIT_PARAM_DESC_SIZE, "block_bits=%d cluster_bits=%d "
		 "blocks_per_group=%d group_count=%d desc_size=%d\n",
		 layout->blocksize_bits, layout->cluster_bits,
		 layout->blocks_per_group, layout->group_count,
		 layout->desc_size);
}
KUNIT_ARRAY_PARAM(mbt_layouts, mbt_test_layouts, mbt_show_layout);

static struct kunit_case mbt_test_cases[] = {
	KUNIT_CASE_PARAM(test_new_blocks_simple, mbt_layouts_gen_params),
	{}
};

static struct kunit_suite mbt_test_suite = {
	.name = "ext4_mballoc_test",
	.init = mbt_kunit_init,
	.exit = mbt_kunit_exit,
	.test_cases = mbt_test_cases,
};

kunit_test_suites(&mbt_test_suite);

MODULE_LICENSE("GPL");