xref: /openbmc/linux/fs/btrfs/tests/extent-io-tests.c (revision cd238eff)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2013 Fusion IO.  All rights reserved.
4  */
5 
6 #include <linux/pagemap.h>
7 #include <linux/sched.h>
8 #include <linux/slab.h>
9 #include <linux/sizes.h>
10 #include "btrfs-tests.h"
11 #include "../ctree.h"
12 #include "../extent_io.h"
13 
14 #define PROCESS_UNLOCK		(1 << 0)
15 #define PROCESS_RELEASE		(1 << 1)
16 #define PROCESS_TEST_LOCKED	(1 << 2)
17 
18 static noinline int process_page_range(struct inode *inode, u64 start, u64 end,
19 				       unsigned long flags)
20 {
21 	int ret;
22 	struct page *pages[16];
23 	unsigned long index = start >> PAGE_SHIFT;
24 	unsigned long end_index = end >> PAGE_SHIFT;
25 	unsigned long nr_pages = end_index - index + 1;
26 	int i;
27 	int count = 0;
28 	int loops = 0;
29 
30 	while (nr_pages > 0) {
31 		ret = find_get_pages_contig(inode->i_mapping, index,
32 				     min_t(unsigned long, nr_pages,
33 				     ARRAY_SIZE(pages)), pages);
34 		for (i = 0; i < ret; i++) {
35 			if (flags & PROCESS_TEST_LOCKED &&
36 			    !PageLocked(pages[i]))
37 				count++;
38 			if (flags & PROCESS_UNLOCK && PageLocked(pages[i]))
39 				unlock_page(pages[i]);
40 			put_page(pages[i]);
41 			if (flags & PROCESS_RELEASE)
42 				put_page(pages[i]);
43 		}
44 		nr_pages -= ret;
45 		index += ret;
46 		cond_resched();
47 		loops++;
48 		if (loops > 100000) {
49 			printk(KERN_ERR
50 		"stuck in a loop, start %llu, end %llu, nr_pages %lu, ret %d\n",
51 				start, end, nr_pages, ret);
52 			break;
53 		}
54 	}
55 	return count;
56 }
57 
58 static int test_find_delalloc(u32 sectorsize)
59 {
60 	struct inode *inode;
61 	struct extent_io_tree tmp;
62 	struct page *page;
63 	struct page *locked_page = NULL;
64 	unsigned long index = 0;
65 	/* In this test we need at least 2 file extents at its maximum size */
66 	u64 max_bytes = BTRFS_MAX_EXTENT_SIZE;
67 	u64 total_dirty = 2 * max_bytes;
68 	u64 start, end, test_start;
69 	bool found;
70 	int ret = -EINVAL;
71 
72 	test_msg("running find delalloc tests");
73 
74 	inode = btrfs_new_test_inode();
75 	if (!inode) {
76 		test_std_err(TEST_ALLOC_INODE);
77 		return -ENOMEM;
78 	}
79 
80 	/*
81 	 * Passing NULL as we don't have fs_info but tracepoints are not used
82 	 * at this point
83 	 */
84 	extent_io_tree_init(NULL, &tmp, IO_TREE_SELFTEST, NULL);
85 
86 	/*
87 	 * First go through and create and mark all of our pages dirty, we pin
88 	 * everything to make sure our pages don't get evicted and screw up our
89 	 * test.
90 	 */
91 	for (index = 0; index < (total_dirty >> PAGE_SHIFT); index++) {
92 		page = find_or_create_page(inode->i_mapping, index, GFP_KERNEL);
93 		if (!page) {
94 			test_err("failed to allocate test page");
95 			ret = -ENOMEM;
96 			goto out;
97 		}
98 		SetPageDirty(page);
99 		if (index) {
100 			unlock_page(page);
101 		} else {
102 			get_page(page);
103 			locked_page = page;
104 		}
105 	}
106 
107 	/* Test this scenario
108 	 * |--- delalloc ---|
109 	 * |---  search  ---|
110 	 */
111 	set_extent_delalloc(&tmp, 0, sectorsize - 1, 0, NULL);
112 	start = 0;
113 	end = 0;
114 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
115 					 &end);
116 	if (!found) {
117 		test_err("should have found at least one delalloc");
118 		goto out_bits;
119 	}
120 	if (start != 0 || end != (sectorsize - 1)) {
121 		test_err("expected start 0 end %u, got start %llu end %llu",
122 			sectorsize - 1, start, end);
123 		goto out_bits;
124 	}
125 	unlock_extent(&tmp, start, end);
126 	unlock_page(locked_page);
127 	put_page(locked_page);
128 
129 	/*
130 	 * Test this scenario
131 	 *
132 	 * |--- delalloc ---|
133 	 *           |--- search ---|
134 	 */
135 	test_start = SZ_64M;
136 	locked_page = find_lock_page(inode->i_mapping,
137 				     test_start >> PAGE_SHIFT);
138 	if (!locked_page) {
139 		test_err("couldn't find the locked page");
140 		goto out_bits;
141 	}
142 	set_extent_delalloc(&tmp, sectorsize, max_bytes - 1, 0, NULL);
143 	start = test_start;
144 	end = 0;
145 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
146 					 &end);
147 	if (!found) {
148 		test_err("couldn't find delalloc in our range");
149 		goto out_bits;
150 	}
151 	if (start != test_start || end != max_bytes - 1) {
152 		test_err("expected start %llu end %llu, got start %llu, end %llu",
153 				test_start, max_bytes - 1, start, end);
154 		goto out_bits;
155 	}
156 	if (process_page_range(inode, start, end,
157 			       PROCESS_TEST_LOCKED | PROCESS_UNLOCK)) {
158 		test_err("there were unlocked pages in the range");
159 		goto out_bits;
160 	}
161 	unlock_extent(&tmp, start, end);
162 	/* locked_page was unlocked above */
163 	put_page(locked_page);
164 
165 	/*
166 	 * Test this scenario
167 	 * |--- delalloc ---|
168 	 *                    |--- search ---|
169 	 */
170 	test_start = max_bytes + sectorsize;
171 	locked_page = find_lock_page(inode->i_mapping, test_start >>
172 				     PAGE_SHIFT);
173 	if (!locked_page) {
174 		test_err("couldn't find the locked page");
175 		goto out_bits;
176 	}
177 	start = test_start;
178 	end = 0;
179 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
180 					 &end);
181 	if (found) {
182 		test_err("found range when we shouldn't have");
183 		goto out_bits;
184 	}
185 	if (end != (u64)-1) {
186 		test_err("did not return the proper end offset");
187 		goto out_bits;
188 	}
189 
190 	/*
191 	 * Test this scenario
192 	 * [------- delalloc -------|
193 	 * [max_bytes]|-- search--|
194 	 *
195 	 * We are re-using our test_start from above since it works out well.
196 	 */
197 	set_extent_delalloc(&tmp, max_bytes, total_dirty - 1, 0, NULL);
198 	start = test_start;
199 	end = 0;
200 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
201 					 &end);
202 	if (!found) {
203 		test_err("didn't find our range");
204 		goto out_bits;
205 	}
206 	if (start != test_start || end != total_dirty - 1) {
207 		test_err("expected start %llu end %llu, got start %llu end %llu",
208 			 test_start, total_dirty - 1, start, end);
209 		goto out_bits;
210 	}
211 	if (process_page_range(inode, start, end,
212 			       PROCESS_TEST_LOCKED | PROCESS_UNLOCK)) {
213 		test_err("pages in range were not all locked");
214 		goto out_bits;
215 	}
216 	unlock_extent(&tmp, start, end);
217 
218 	/*
219 	 * Now to test where we run into a page that is no longer dirty in the
220 	 * range we want to find.
221 	 */
222 	page = find_get_page(inode->i_mapping,
223 			     (max_bytes + SZ_1M) >> PAGE_SHIFT);
224 	if (!page) {
225 		test_err("couldn't find our page");
226 		goto out_bits;
227 	}
228 	ClearPageDirty(page);
229 	put_page(page);
230 
231 	/* We unlocked it in the previous test */
232 	lock_page(locked_page);
233 	start = test_start;
234 	end = 0;
235 	/*
236 	 * Currently if we fail to find dirty pages in the delalloc range we
237 	 * will adjust max_bytes down to PAGE_SIZE and then re-search.  If
238 	 * this changes at any point in the future we will need to fix this
239 	 * tests expected behavior.
240 	 */
241 	found = find_lock_delalloc_range(inode, &tmp, locked_page, &start,
242 					 &end);
243 	if (!found) {
244 		test_err("didn't find our range");
245 		goto out_bits;
246 	}
247 	if (start != test_start && end != test_start + PAGE_SIZE - 1) {
248 		test_err("expected start %llu end %llu, got start %llu end %llu",
249 			 test_start, test_start + PAGE_SIZE - 1, start, end);
250 		goto out_bits;
251 	}
252 	if (process_page_range(inode, start, end, PROCESS_TEST_LOCKED |
253 			       PROCESS_UNLOCK)) {
254 		test_err("pages in range were not all locked");
255 		goto out_bits;
256 	}
257 	ret = 0;
258 out_bits:
259 	clear_extent_bits(&tmp, 0, total_dirty - 1, (unsigned)-1);
260 out:
261 	if (locked_page)
262 		put_page(locked_page);
263 	process_page_range(inode, 0, total_dirty - 1,
264 			   PROCESS_UNLOCK | PROCESS_RELEASE);
265 	iput(inode);
266 	return ret;
267 }
268 
269 static int check_eb_bitmap(unsigned long *bitmap, struct extent_buffer *eb,
270 			   unsigned long len)
271 {
272 	unsigned long i;
273 
274 	for (i = 0; i < len * BITS_PER_BYTE; i++) {
275 		int bit, bit1;
276 
277 		bit = !!test_bit(i, bitmap);
278 		bit1 = !!extent_buffer_test_bit(eb, 0, i);
279 		if (bit1 != bit) {
280 			test_err("bits do not match");
281 			return -EINVAL;
282 		}
283 
284 		bit1 = !!extent_buffer_test_bit(eb, i / BITS_PER_BYTE,
285 						i % BITS_PER_BYTE);
286 		if (bit1 != bit) {
287 			test_err("offset bits do not match");
288 			return -EINVAL;
289 		}
290 	}
291 	return 0;
292 }
293 
294 static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb,
295 			     unsigned long len)
296 {
297 	unsigned long i, j;
298 	u32 x;
299 	int ret;
300 
301 	memset(bitmap, 0, len);
302 	memzero_extent_buffer(eb, 0, len);
303 	if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) {
304 		test_err("bitmap was not zeroed");
305 		return -EINVAL;
306 	}
307 
308 	bitmap_set(bitmap, 0, len * BITS_PER_BYTE);
309 	extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE);
310 	ret = check_eb_bitmap(bitmap, eb, len);
311 	if (ret) {
312 		test_err("setting all bits failed");
313 		return ret;
314 	}
315 
316 	bitmap_clear(bitmap, 0, len * BITS_PER_BYTE);
317 	extent_buffer_bitmap_clear(eb, 0, 0, len * BITS_PER_BYTE);
318 	ret = check_eb_bitmap(bitmap, eb, len);
319 	if (ret) {
320 		test_err("clearing all bits failed");
321 		return ret;
322 	}
323 
324 	/* Straddling pages test */
325 	if (len > PAGE_SIZE) {
326 		bitmap_set(bitmap,
327 			(PAGE_SIZE - sizeof(long) / 2) * BITS_PER_BYTE,
328 			sizeof(long) * BITS_PER_BYTE);
329 		extent_buffer_bitmap_set(eb, PAGE_SIZE - sizeof(long) / 2, 0,
330 					sizeof(long) * BITS_PER_BYTE);
331 		ret = check_eb_bitmap(bitmap, eb, len);
332 		if (ret) {
333 			test_err("setting straddling pages failed");
334 			return ret;
335 		}
336 
337 		bitmap_set(bitmap, 0, len * BITS_PER_BYTE);
338 		bitmap_clear(bitmap,
339 			(PAGE_SIZE - sizeof(long) / 2) * BITS_PER_BYTE,
340 			sizeof(long) * BITS_PER_BYTE);
341 		extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE);
342 		extent_buffer_bitmap_clear(eb, PAGE_SIZE - sizeof(long) / 2, 0,
343 					sizeof(long) * BITS_PER_BYTE);
344 		ret = check_eb_bitmap(bitmap, eb, len);
345 		if (ret) {
346 			test_err("clearing straddling pages failed");
347 			return ret;
348 		}
349 	}
350 
351 	/*
352 	 * Generate a wonky pseudo-random bit pattern for the sake of not using
353 	 * something repetitive that could miss some hypothetical off-by-n bug.
354 	 */
355 	x = 0;
356 	bitmap_clear(bitmap, 0, len * BITS_PER_BYTE);
357 	extent_buffer_bitmap_clear(eb, 0, 0, len * BITS_PER_BYTE);
358 	for (i = 0; i < len * BITS_PER_BYTE / 32; i++) {
359 		x = (0x19660dULL * (u64)x + 0x3c6ef35fULL) & 0xffffffffU;
360 		for (j = 0; j < 32; j++) {
361 			if (x & (1U << j)) {
362 				bitmap_set(bitmap, i * 32 + j, 1);
363 				extent_buffer_bitmap_set(eb, 0, i * 32 + j, 1);
364 			}
365 		}
366 	}
367 
368 	ret = check_eb_bitmap(bitmap, eb, len);
369 	if (ret) {
370 		test_err("random bit pattern failed");
371 		return ret;
372 	}
373 
374 	return 0;
375 }
376 
377 static int test_eb_bitmaps(u32 sectorsize, u32 nodesize)
378 {
379 	struct btrfs_fs_info *fs_info;
380 	unsigned long len;
381 	unsigned long *bitmap = NULL;
382 	struct extent_buffer *eb = NULL;
383 	int ret;
384 
385 	test_msg("running extent buffer bitmap tests");
386 
387 	/*
388 	 * In ppc64, sectorsize can be 64K, thus 4 * 64K will be larger than
389 	 * BTRFS_MAX_METADATA_BLOCKSIZE.
390 	 */
391 	len = (sectorsize < BTRFS_MAX_METADATA_BLOCKSIZE)
392 		? sectorsize * 4 : sectorsize;
393 
394 	fs_info = btrfs_alloc_dummy_fs_info(len, len);
395 	if (!fs_info) {
396 		test_std_err(TEST_ALLOC_FS_INFO);
397 		return -ENOMEM;
398 	}
399 
400 	bitmap = kmalloc(len, GFP_KERNEL);
401 	if (!bitmap) {
402 		test_err("couldn't allocate test bitmap");
403 		ret = -ENOMEM;
404 		goto out;
405 	}
406 
407 	eb = __alloc_dummy_extent_buffer(fs_info, 0, len);
408 	if (!eb) {
409 		test_std_err(TEST_ALLOC_ROOT);
410 		ret = -ENOMEM;
411 		goto out;
412 	}
413 
414 	ret = __test_eb_bitmaps(bitmap, eb, len);
415 	if (ret)
416 		goto out;
417 
418 	/* Do it over again with an extent buffer which isn't page-aligned. */
419 	free_extent_buffer(eb);
420 	eb = __alloc_dummy_extent_buffer(fs_info, nodesize / 2, len);
421 	if (!eb) {
422 		test_std_err(TEST_ALLOC_ROOT);
423 		ret = -ENOMEM;
424 		goto out;
425 	}
426 
427 	ret = __test_eb_bitmaps(bitmap, eb, len);
428 out:
429 	free_extent_buffer(eb);
430 	kfree(bitmap);
431 	btrfs_free_dummy_fs_info(fs_info);
432 	return ret;
433 }
434 
435 int btrfs_test_extent_io(u32 sectorsize, u32 nodesize)
436 {
437 	int ret;
438 
439 	test_msg("running extent I/O tests");
440 
441 	ret = test_find_delalloc(sectorsize);
442 	if (ret)
443 		goto out;
444 
445 	ret = test_eb_bitmaps(sectorsize, nodesize);
446 out:
447 	return ret;
448 }
449