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c1d7c514 | 1 | // SPDX-License-Identifier: GPL-2.0 |
a5ed9182 OS |
2 | /* |
3 | * Copyright (C) 2015 Facebook. All rights reserved. | |
a5ed9182 OS |
4 | */ |
5 | ||
6 | #include <linux/kernel.h> | |
25ff17e8 | 7 | #include <linux/sched/mm.h> |
a5ed9182 OS |
8 | #include "ctree.h" |
9 | #include "disk-io.h" | |
10 | #include "locking.h" | |
11 | #include "free-space-tree.h" | |
12 | #include "transaction.h" | |
13 | ||
14 | static int __add_block_group_free_space(struct btrfs_trans_handle *trans, | |
a5ed9182 OS |
15 | struct btrfs_block_group_cache *block_group, |
16 | struct btrfs_path *path); | |
17 | ||
18 | void set_free_space_tree_thresholds(struct btrfs_block_group_cache *cache) | |
19 | { | |
20 | u32 bitmap_range; | |
21 | size_t bitmap_size; | |
22 | u64 num_bitmaps, total_bitmap_size; | |
23 | ||
24 | /* | |
25 | * We convert to bitmaps when the disk space required for using extents | |
26 | * exceeds that required for using bitmaps. | |
27 | */ | |
da17066c | 28 | bitmap_range = cache->fs_info->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS; |
a5ed9182 OS |
29 | num_bitmaps = div_u64(cache->key.offset + bitmap_range - 1, |
30 | bitmap_range); | |
31 | bitmap_size = sizeof(struct btrfs_item) + BTRFS_FREE_SPACE_BITMAP_SIZE; | |
32 | total_bitmap_size = num_bitmaps * bitmap_size; | |
33 | cache->bitmap_high_thresh = div_u64(total_bitmap_size, | |
34 | sizeof(struct btrfs_item)); | |
35 | ||
36 | /* | |
37 | * We allow for a small buffer between the high threshold and low | |
38 | * threshold to avoid thrashing back and forth between the two formats. | |
39 | */ | |
40 | if (cache->bitmap_high_thresh > 100) | |
41 | cache->bitmap_low_thresh = cache->bitmap_high_thresh - 100; | |
42 | else | |
43 | cache->bitmap_low_thresh = 0; | |
44 | } | |
45 | ||
46 | static int add_new_free_space_info(struct btrfs_trans_handle *trans, | |
a5ed9182 OS |
47 | struct btrfs_block_group_cache *block_group, |
48 | struct btrfs_path *path) | |
49 | { | |
66afee18 | 50 | struct btrfs_root *root = trans->fs_info->free_space_root; |
a5ed9182 OS |
51 | struct btrfs_free_space_info *info; |
52 | struct btrfs_key key; | |
53 | struct extent_buffer *leaf; | |
54 | int ret; | |
55 | ||
56 | key.objectid = block_group->key.objectid; | |
57 | key.type = BTRFS_FREE_SPACE_INFO_KEY; | |
58 | key.offset = block_group->key.offset; | |
59 | ||
60 | ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*info)); | |
61 | if (ret) | |
62 | goto out; | |
63 | ||
64 | leaf = path->nodes[0]; | |
65 | info = btrfs_item_ptr(leaf, path->slots[0], | |
66 | struct btrfs_free_space_info); | |
67 | btrfs_set_free_space_extent_count(leaf, info, 0); | |
68 | btrfs_set_free_space_flags(leaf, info, 0); | |
69 | btrfs_mark_buffer_dirty(leaf); | |
70 | ||
71 | ret = 0; | |
72 | out: | |
73 | btrfs_release_path(path); | |
74 | return ret; | |
75 | } | |
76 | ||
77 | struct btrfs_free_space_info * | |
78 | search_free_space_info(struct btrfs_trans_handle *trans, | |
79 | struct btrfs_fs_info *fs_info, | |
80 | struct btrfs_block_group_cache *block_group, | |
81 | struct btrfs_path *path, int cow) | |
82 | { | |
83 | struct btrfs_root *root = fs_info->free_space_root; | |
84 | struct btrfs_key key; | |
85 | int ret; | |
86 | ||
87 | key.objectid = block_group->key.objectid; | |
88 | key.type = BTRFS_FREE_SPACE_INFO_KEY; | |
89 | key.offset = block_group->key.offset; | |
90 | ||
91 | ret = btrfs_search_slot(trans, root, &key, path, 0, cow); | |
92 | if (ret < 0) | |
93 | return ERR_PTR(ret); | |
94 | if (ret != 0) { | |
ab8d0fc4 | 95 | btrfs_warn(fs_info, "missing free space info for %llu", |
a5ed9182 OS |
96 | block_group->key.objectid); |
97 | ASSERT(0); | |
98 | return ERR_PTR(-ENOENT); | |
99 | } | |
100 | ||
101 | return btrfs_item_ptr(path->nodes[0], path->slots[0], | |
102 | struct btrfs_free_space_info); | |
103 | } | |
104 | ||
105 | /* | |
106 | * btrfs_search_slot() but we're looking for the greatest key less than the | |
107 | * passed key. | |
108 | */ | |
109 | static int btrfs_search_prev_slot(struct btrfs_trans_handle *trans, | |
110 | struct btrfs_root *root, | |
111 | struct btrfs_key *key, struct btrfs_path *p, | |
112 | int ins_len, int cow) | |
113 | { | |
114 | int ret; | |
115 | ||
116 | ret = btrfs_search_slot(trans, root, key, p, ins_len, cow); | |
117 | if (ret < 0) | |
118 | return ret; | |
119 | ||
120 | if (ret == 0) { | |
121 | ASSERT(0); | |
122 | return -EIO; | |
123 | } | |
124 | ||
125 | if (p->slots[0] == 0) { | |
126 | ASSERT(0); | |
127 | return -EIO; | |
128 | } | |
129 | p->slots[0]--; | |
130 | ||
131 | return 0; | |
132 | } | |
133 | ||
134 | static inline u32 free_space_bitmap_size(u64 size, u32 sectorsize) | |
135 | { | |
136 | return DIV_ROUND_UP((u32)div_u64(size, sectorsize), BITS_PER_BYTE); | |
137 | } | |
138 | ||
a565971f | 139 | static unsigned long *alloc_bitmap(u32 bitmap_size) |
a5ed9182 | 140 | { |
a565971f | 141 | unsigned long *ret; |
25ff17e8 | 142 | unsigned int nofs_flag; |
a565971f | 143 | u32 bitmap_rounded_size = round_up(bitmap_size, sizeof(unsigned long)); |
79b134a2 DS |
144 | |
145 | /* | |
25ff17e8 OS |
146 | * GFP_NOFS doesn't work with kvmalloc(), but we really can't recurse |
147 | * into the filesystem as the free space bitmap can be modified in the | |
148 | * critical section of a transaction commit. | |
149 | * | |
150 | * TODO: push the memalloc_nofs_{save,restore}() to the caller where we | |
151 | * know that recursion is unsafe. | |
79b134a2 | 152 | */ |
25ff17e8 | 153 | nofs_flag = memalloc_nofs_save(); |
a565971f | 154 | ret = kvzalloc(bitmap_rounded_size, GFP_KERNEL); |
25ff17e8 OS |
155 | memalloc_nofs_restore(nofs_flag); |
156 | return ret; | |
a5ed9182 OS |
157 | } |
158 | ||
a565971f | 159 | static void le_bitmap_set(unsigned long *map, unsigned int start, int len) |
6faa8f47 | 160 | { |
a565971f | 161 | u8 *p = ((u8 *)map) + BIT_BYTE(start); |
6faa8f47 HM |
162 | const unsigned int size = start + len; |
163 | int bits_to_set = BITS_PER_BYTE - (start % BITS_PER_BYTE); | |
164 | u8 mask_to_set = BITMAP_FIRST_BYTE_MASK(start); | |
165 | ||
166 | while (len - bits_to_set >= 0) { | |
167 | *p |= mask_to_set; | |
168 | len -= bits_to_set; | |
169 | bits_to_set = BITS_PER_BYTE; | |
170 | mask_to_set = ~0; | |
171 | p++; | |
172 | } | |
173 | if (len) { | |
174 | mask_to_set &= BITMAP_LAST_BYTE_MASK(size); | |
175 | *p |= mask_to_set; | |
176 | } | |
177 | } | |
178 | ||
a5ed9182 | 179 | int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans, |
a5ed9182 OS |
180 | struct btrfs_block_group_cache *block_group, |
181 | struct btrfs_path *path) | |
182 | { | |
719fb4de | 183 | struct btrfs_fs_info *fs_info = trans->fs_info; |
a5ed9182 OS |
184 | struct btrfs_root *root = fs_info->free_space_root; |
185 | struct btrfs_free_space_info *info; | |
186 | struct btrfs_key key, found_key; | |
187 | struct extent_buffer *leaf; | |
a565971f HM |
188 | unsigned long *bitmap; |
189 | char *bitmap_cursor; | |
a5ed9182 OS |
190 | u64 start, end; |
191 | u64 bitmap_range, i; | |
192 | u32 bitmap_size, flags, expected_extent_count; | |
193 | u32 extent_count = 0; | |
194 | int done = 0, nr; | |
195 | int ret; | |
196 | ||
197 | bitmap_size = free_space_bitmap_size(block_group->key.offset, | |
0b246afa | 198 | fs_info->sectorsize); |
a5ed9182 OS |
199 | bitmap = alloc_bitmap(bitmap_size); |
200 | if (!bitmap) { | |
201 | ret = -ENOMEM; | |
202 | goto out; | |
203 | } | |
204 | ||
205 | start = block_group->key.objectid; | |
206 | end = block_group->key.objectid + block_group->key.offset; | |
207 | ||
208 | key.objectid = end - 1; | |
209 | key.type = (u8)-1; | |
210 | key.offset = (u64)-1; | |
211 | ||
212 | while (!done) { | |
213 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
214 | if (ret) | |
215 | goto out; | |
216 | ||
217 | leaf = path->nodes[0]; | |
218 | nr = 0; | |
219 | path->slots[0]++; | |
220 | while (path->slots[0] > 0) { | |
221 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); | |
222 | ||
223 | if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { | |
224 | ASSERT(found_key.objectid == block_group->key.objectid); | |
225 | ASSERT(found_key.offset == block_group->key.offset); | |
226 | done = 1; | |
227 | break; | |
228 | } else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY) { | |
229 | u64 first, last; | |
230 | ||
231 | ASSERT(found_key.objectid >= start); | |
232 | ASSERT(found_key.objectid < end); | |
233 | ASSERT(found_key.objectid + found_key.offset <= end); | |
234 | ||
235 | first = div_u64(found_key.objectid - start, | |
0b246afa | 236 | fs_info->sectorsize); |
a5ed9182 | 237 | last = div_u64(found_key.objectid + found_key.offset - start, |
0b246afa | 238 | fs_info->sectorsize); |
2fe1d551 | 239 | le_bitmap_set(bitmap, first, last - first); |
a5ed9182 OS |
240 | |
241 | extent_count++; | |
242 | nr++; | |
243 | path->slots[0]--; | |
244 | } else { | |
245 | ASSERT(0); | |
246 | } | |
247 | } | |
248 | ||
249 | ret = btrfs_del_items(trans, root, path, path->slots[0], nr); | |
250 | if (ret) | |
251 | goto out; | |
252 | btrfs_release_path(path); | |
253 | } | |
254 | ||
255 | info = search_free_space_info(trans, fs_info, block_group, path, 1); | |
256 | if (IS_ERR(info)) { | |
257 | ret = PTR_ERR(info); | |
258 | goto out; | |
259 | } | |
260 | leaf = path->nodes[0]; | |
261 | flags = btrfs_free_space_flags(leaf, info); | |
262 | flags |= BTRFS_FREE_SPACE_USING_BITMAPS; | |
263 | btrfs_set_free_space_flags(leaf, info, flags); | |
264 | expected_extent_count = btrfs_free_space_extent_count(leaf, info); | |
265 | btrfs_mark_buffer_dirty(leaf); | |
266 | btrfs_release_path(path); | |
267 | ||
268 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
269 | btrfs_err(fs_info, |
270 | "incorrect extent count for %llu; counted %u, expected %u", | |
a5ed9182 OS |
271 | block_group->key.objectid, extent_count, |
272 | expected_extent_count); | |
273 | ASSERT(0); | |
274 | ret = -EIO; | |
275 | goto out; | |
276 | } | |
277 | ||
a565971f | 278 | bitmap_cursor = (char *)bitmap; |
0b246afa | 279 | bitmap_range = fs_info->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS; |
a5ed9182 OS |
280 | i = start; |
281 | while (i < end) { | |
282 | unsigned long ptr; | |
283 | u64 extent_size; | |
284 | u32 data_size; | |
285 | ||
286 | extent_size = min(end - i, bitmap_range); | |
287 | data_size = free_space_bitmap_size(extent_size, | |
0b246afa | 288 | fs_info->sectorsize); |
a5ed9182 OS |
289 | |
290 | key.objectid = i; | |
291 | key.type = BTRFS_FREE_SPACE_BITMAP_KEY; | |
292 | key.offset = extent_size; | |
293 | ||
294 | ret = btrfs_insert_empty_item(trans, root, path, &key, | |
295 | data_size); | |
296 | if (ret) | |
297 | goto out; | |
298 | ||
299 | leaf = path->nodes[0]; | |
300 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
301 | write_extent_buffer(leaf, bitmap_cursor, ptr, | |
302 | data_size); | |
303 | btrfs_mark_buffer_dirty(leaf); | |
304 | btrfs_release_path(path); | |
305 | ||
306 | i += extent_size; | |
307 | bitmap_cursor += data_size; | |
308 | } | |
309 | ||
310 | ret = 0; | |
311 | out: | |
79b134a2 | 312 | kvfree(bitmap); |
a5ed9182 | 313 | if (ret) |
66642832 | 314 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
315 | return ret; |
316 | } | |
317 | ||
318 | int convert_free_space_to_extents(struct btrfs_trans_handle *trans, | |
a5ed9182 OS |
319 | struct btrfs_block_group_cache *block_group, |
320 | struct btrfs_path *path) | |
321 | { | |
5296c2bf | 322 | struct btrfs_fs_info *fs_info = trans->fs_info; |
a5ed9182 OS |
323 | struct btrfs_root *root = fs_info->free_space_root; |
324 | struct btrfs_free_space_info *info; | |
325 | struct btrfs_key key, found_key; | |
326 | struct extent_buffer *leaf; | |
a565971f | 327 | unsigned long *bitmap; |
a5ed9182 | 328 | u64 start, end; |
a5ed9182 | 329 | u32 bitmap_size, flags, expected_extent_count; |
a565971f | 330 | unsigned long nrbits, start_bit, end_bit; |
a5ed9182 OS |
331 | u32 extent_count = 0; |
332 | int done = 0, nr; | |
333 | int ret; | |
334 | ||
335 | bitmap_size = free_space_bitmap_size(block_group->key.offset, | |
0b246afa | 336 | fs_info->sectorsize); |
a5ed9182 OS |
337 | bitmap = alloc_bitmap(bitmap_size); |
338 | if (!bitmap) { | |
339 | ret = -ENOMEM; | |
340 | goto out; | |
341 | } | |
342 | ||
343 | start = block_group->key.objectid; | |
344 | end = block_group->key.objectid + block_group->key.offset; | |
345 | ||
346 | key.objectid = end - 1; | |
347 | key.type = (u8)-1; | |
348 | key.offset = (u64)-1; | |
349 | ||
350 | while (!done) { | |
351 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
352 | if (ret) | |
353 | goto out; | |
354 | ||
355 | leaf = path->nodes[0]; | |
356 | nr = 0; | |
357 | path->slots[0]++; | |
358 | while (path->slots[0] > 0) { | |
359 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); | |
360 | ||
361 | if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { | |
362 | ASSERT(found_key.objectid == block_group->key.objectid); | |
363 | ASSERT(found_key.offset == block_group->key.offset); | |
364 | done = 1; | |
365 | break; | |
366 | } else if (found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) { | |
367 | unsigned long ptr; | |
a565971f | 368 | char *bitmap_cursor; |
a5ed9182 OS |
369 | u32 bitmap_pos, data_size; |
370 | ||
371 | ASSERT(found_key.objectid >= start); | |
372 | ASSERT(found_key.objectid < end); | |
373 | ASSERT(found_key.objectid + found_key.offset <= end); | |
374 | ||
375 | bitmap_pos = div_u64(found_key.objectid - start, | |
0b246afa | 376 | fs_info->sectorsize * |
a5ed9182 | 377 | BITS_PER_BYTE); |
a565971f | 378 | bitmap_cursor = ((char *)bitmap) + bitmap_pos; |
a5ed9182 | 379 | data_size = free_space_bitmap_size(found_key.offset, |
0b246afa | 380 | fs_info->sectorsize); |
a5ed9182 OS |
381 | |
382 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0] - 1); | |
383 | read_extent_buffer(leaf, bitmap_cursor, ptr, | |
384 | data_size); | |
385 | ||
386 | nr++; | |
387 | path->slots[0]--; | |
388 | } else { | |
389 | ASSERT(0); | |
390 | } | |
391 | } | |
392 | ||
393 | ret = btrfs_del_items(trans, root, path, path->slots[0], nr); | |
394 | if (ret) | |
395 | goto out; | |
396 | btrfs_release_path(path); | |
397 | } | |
398 | ||
399 | info = search_free_space_info(trans, fs_info, block_group, path, 1); | |
400 | if (IS_ERR(info)) { | |
401 | ret = PTR_ERR(info); | |
402 | goto out; | |
403 | } | |
404 | leaf = path->nodes[0]; | |
405 | flags = btrfs_free_space_flags(leaf, info); | |
406 | flags &= ~BTRFS_FREE_SPACE_USING_BITMAPS; | |
407 | btrfs_set_free_space_flags(leaf, info, flags); | |
408 | expected_extent_count = btrfs_free_space_extent_count(leaf, info); | |
409 | btrfs_mark_buffer_dirty(leaf); | |
410 | btrfs_release_path(path); | |
411 | ||
a565971f HM |
412 | nrbits = div_u64(block_group->key.offset, block_group->fs_info->sectorsize); |
413 | start_bit = find_next_bit_le(bitmap, nrbits, 0); | |
414 | ||
415 | while (start_bit < nrbits) { | |
416 | end_bit = find_next_zero_bit_le(bitmap, nrbits, start_bit); | |
417 | ASSERT(start_bit < end_bit); | |
418 | ||
419 | key.objectid = start + start_bit * block_group->fs_info->sectorsize; | |
a5ed9182 | 420 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; |
a565971f | 421 | key.offset = (end_bit - start_bit) * block_group->fs_info->sectorsize; |
a5ed9182 OS |
422 | |
423 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
424 | if (ret) | |
425 | goto out; | |
426 | btrfs_release_path(path); | |
427 | ||
428 | extent_count++; | |
a565971f HM |
429 | |
430 | start_bit = find_next_bit_le(bitmap, nrbits, end_bit); | |
a5ed9182 OS |
431 | } |
432 | ||
433 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
434 | btrfs_err(fs_info, |
435 | "incorrect extent count for %llu; counted %u, expected %u", | |
a5ed9182 OS |
436 | block_group->key.objectid, extent_count, |
437 | expected_extent_count); | |
438 | ASSERT(0); | |
439 | ret = -EIO; | |
440 | goto out; | |
441 | } | |
442 | ||
443 | ret = 0; | |
444 | out: | |
79b134a2 | 445 | kvfree(bitmap); |
a5ed9182 | 446 | if (ret) |
66642832 | 447 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
448 | return ret; |
449 | } | |
450 | ||
451 | static int update_free_space_extent_count(struct btrfs_trans_handle *trans, | |
452 | struct btrfs_fs_info *fs_info, | |
453 | struct btrfs_block_group_cache *block_group, | |
454 | struct btrfs_path *path, | |
455 | int new_extents) | |
456 | { | |
457 | struct btrfs_free_space_info *info; | |
458 | u32 flags; | |
459 | u32 extent_count; | |
460 | int ret = 0; | |
461 | ||
462 | if (new_extents == 0) | |
463 | return 0; | |
464 | ||
465 | info = search_free_space_info(trans, fs_info, block_group, path, 1); | |
466 | if (IS_ERR(info)) { | |
467 | ret = PTR_ERR(info); | |
468 | goto out; | |
469 | } | |
470 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
471 | extent_count = btrfs_free_space_extent_count(path->nodes[0], info); | |
472 | ||
473 | extent_count += new_extents; | |
474 | btrfs_set_free_space_extent_count(path->nodes[0], info, extent_count); | |
475 | btrfs_mark_buffer_dirty(path->nodes[0]); | |
476 | btrfs_release_path(path); | |
477 | ||
478 | if (!(flags & BTRFS_FREE_SPACE_USING_BITMAPS) && | |
479 | extent_count > block_group->bitmap_high_thresh) { | |
719fb4de | 480 | ret = convert_free_space_to_bitmaps(trans, block_group, path); |
a5ed9182 OS |
481 | } else if ((flags & BTRFS_FREE_SPACE_USING_BITMAPS) && |
482 | extent_count < block_group->bitmap_low_thresh) { | |
5296c2bf | 483 | ret = convert_free_space_to_extents(trans, block_group, path); |
a5ed9182 OS |
484 | } |
485 | ||
486 | out: | |
487 | return ret; | |
488 | } | |
489 | ||
490 | int free_space_test_bit(struct btrfs_block_group_cache *block_group, | |
491 | struct btrfs_path *path, u64 offset) | |
492 | { | |
493 | struct extent_buffer *leaf; | |
494 | struct btrfs_key key; | |
495 | u64 found_start, found_end; | |
496 | unsigned long ptr, i; | |
497 | ||
498 | leaf = path->nodes[0]; | |
499 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
500 | ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); | |
501 | ||
502 | found_start = key.objectid; | |
503 | found_end = key.objectid + key.offset; | |
504 | ASSERT(offset >= found_start && offset < found_end); | |
505 | ||
506 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
da17066c JM |
507 | i = div_u64(offset - found_start, |
508 | block_group->fs_info->sectorsize); | |
a5ed9182 OS |
509 | return !!extent_buffer_test_bit(leaf, ptr, i); |
510 | } | |
511 | ||
512 | static void free_space_set_bits(struct btrfs_block_group_cache *block_group, | |
513 | struct btrfs_path *path, u64 *start, u64 *size, | |
514 | int bit) | |
515 | { | |
0b246afa | 516 | struct btrfs_fs_info *fs_info = block_group->fs_info; |
a5ed9182 OS |
517 | struct extent_buffer *leaf; |
518 | struct btrfs_key key; | |
519 | u64 end = *start + *size; | |
520 | u64 found_start, found_end; | |
521 | unsigned long ptr, first, last; | |
522 | ||
523 | leaf = path->nodes[0]; | |
524 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
525 | ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); | |
526 | ||
527 | found_start = key.objectid; | |
528 | found_end = key.objectid + key.offset; | |
529 | ASSERT(*start >= found_start && *start < found_end); | |
530 | ASSERT(end > found_start); | |
531 | ||
532 | if (end > found_end) | |
533 | end = found_end; | |
534 | ||
535 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
0b246afa JM |
536 | first = div_u64(*start - found_start, fs_info->sectorsize); |
537 | last = div_u64(end - found_start, fs_info->sectorsize); | |
a5ed9182 OS |
538 | if (bit) |
539 | extent_buffer_bitmap_set(leaf, ptr, first, last - first); | |
540 | else | |
541 | extent_buffer_bitmap_clear(leaf, ptr, first, last - first); | |
542 | btrfs_mark_buffer_dirty(leaf); | |
543 | ||
544 | *size -= end - *start; | |
545 | *start = end; | |
546 | } | |
547 | ||
548 | /* | |
549 | * We can't use btrfs_next_item() in modify_free_space_bitmap() because | |
550 | * btrfs_next_leaf() doesn't get the path for writing. We can forgo the fancy | |
551 | * tree walking in btrfs_next_leaf() anyways because we know exactly what we're | |
552 | * looking for. | |
553 | */ | |
554 | static int free_space_next_bitmap(struct btrfs_trans_handle *trans, | |
555 | struct btrfs_root *root, struct btrfs_path *p) | |
556 | { | |
557 | struct btrfs_key key; | |
558 | ||
559 | if (p->slots[0] + 1 < btrfs_header_nritems(p->nodes[0])) { | |
560 | p->slots[0]++; | |
561 | return 0; | |
562 | } | |
563 | ||
564 | btrfs_item_key_to_cpu(p->nodes[0], &key, p->slots[0]); | |
565 | btrfs_release_path(p); | |
566 | ||
567 | key.objectid += key.offset; | |
568 | key.type = (u8)-1; | |
569 | key.offset = (u64)-1; | |
570 | ||
571 | return btrfs_search_prev_slot(trans, root, &key, p, 0, 1); | |
572 | } | |
573 | ||
574 | /* | |
575 | * If remove is 1, then we are removing free space, thus clearing bits in the | |
576 | * bitmap. If remove is 0, then we are adding free space, thus setting bits in | |
577 | * the bitmap. | |
578 | */ | |
579 | static int modify_free_space_bitmap(struct btrfs_trans_handle *trans, | |
580 | struct btrfs_fs_info *fs_info, | |
581 | struct btrfs_block_group_cache *block_group, | |
582 | struct btrfs_path *path, | |
583 | u64 start, u64 size, int remove) | |
584 | { | |
585 | struct btrfs_root *root = fs_info->free_space_root; | |
586 | struct btrfs_key key; | |
587 | u64 end = start + size; | |
588 | u64 cur_start, cur_size; | |
589 | int prev_bit, next_bit; | |
590 | int new_extents; | |
591 | int ret; | |
592 | ||
593 | /* | |
594 | * Read the bit for the block immediately before the extent of space if | |
595 | * that block is within the block group. | |
596 | */ | |
597 | if (start > block_group->key.objectid) { | |
da17066c | 598 | u64 prev_block = start - block_group->fs_info->sectorsize; |
a5ed9182 OS |
599 | |
600 | key.objectid = prev_block; | |
601 | key.type = (u8)-1; | |
602 | key.offset = (u64)-1; | |
603 | ||
604 | ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1); | |
605 | if (ret) | |
606 | goto out; | |
607 | ||
608 | prev_bit = free_space_test_bit(block_group, path, prev_block); | |
609 | ||
610 | /* The previous block may have been in the previous bitmap. */ | |
611 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
612 | if (start >= key.objectid + key.offset) { | |
613 | ret = free_space_next_bitmap(trans, root, path); | |
614 | if (ret) | |
615 | goto out; | |
616 | } | |
617 | } else { | |
618 | key.objectid = start; | |
619 | key.type = (u8)-1; | |
620 | key.offset = (u64)-1; | |
621 | ||
622 | ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1); | |
623 | if (ret) | |
624 | goto out; | |
625 | ||
626 | prev_bit = -1; | |
627 | } | |
628 | ||
629 | /* | |
630 | * Iterate over all of the bitmaps overlapped by the extent of space, | |
631 | * clearing/setting bits as required. | |
632 | */ | |
633 | cur_start = start; | |
634 | cur_size = size; | |
635 | while (1) { | |
636 | free_space_set_bits(block_group, path, &cur_start, &cur_size, | |
637 | !remove); | |
638 | if (cur_size == 0) | |
639 | break; | |
640 | ret = free_space_next_bitmap(trans, root, path); | |
641 | if (ret) | |
642 | goto out; | |
643 | } | |
644 | ||
645 | /* | |
646 | * Read the bit for the block immediately after the extent of space if | |
647 | * that block is within the block group. | |
648 | */ | |
649 | if (end < block_group->key.objectid + block_group->key.offset) { | |
650 | /* The next block may be in the next bitmap. */ | |
651 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
652 | if (end >= key.objectid + key.offset) { | |
653 | ret = free_space_next_bitmap(trans, root, path); | |
654 | if (ret) | |
655 | goto out; | |
656 | } | |
657 | ||
658 | next_bit = free_space_test_bit(block_group, path, end); | |
659 | } else { | |
660 | next_bit = -1; | |
661 | } | |
662 | ||
663 | if (remove) { | |
664 | new_extents = -1; | |
665 | if (prev_bit == 1) { | |
666 | /* Leftover on the left. */ | |
667 | new_extents++; | |
668 | } | |
669 | if (next_bit == 1) { | |
670 | /* Leftover on the right. */ | |
671 | new_extents++; | |
672 | } | |
673 | } else { | |
674 | new_extents = 1; | |
675 | if (prev_bit == 1) { | |
676 | /* Merging with neighbor on the left. */ | |
677 | new_extents--; | |
678 | } | |
679 | if (next_bit == 1) { | |
680 | /* Merging with neighbor on the right. */ | |
681 | new_extents--; | |
682 | } | |
683 | } | |
684 | ||
685 | btrfs_release_path(path); | |
686 | ret = update_free_space_extent_count(trans, fs_info, block_group, path, | |
687 | new_extents); | |
688 | ||
689 | out: | |
690 | return ret; | |
691 | } | |
692 | ||
693 | static int remove_free_space_extent(struct btrfs_trans_handle *trans, | |
694 | struct btrfs_fs_info *fs_info, | |
695 | struct btrfs_block_group_cache *block_group, | |
696 | struct btrfs_path *path, | |
697 | u64 start, u64 size) | |
698 | { | |
699 | struct btrfs_root *root = fs_info->free_space_root; | |
700 | struct btrfs_key key; | |
701 | u64 found_start, found_end; | |
702 | u64 end = start + size; | |
703 | int new_extents = -1; | |
704 | int ret; | |
705 | ||
706 | key.objectid = start; | |
707 | key.type = (u8)-1; | |
708 | key.offset = (u64)-1; | |
709 | ||
710 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
711 | if (ret) | |
712 | goto out; | |
713 | ||
714 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
715 | ||
716 | ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY); | |
717 | ||
718 | found_start = key.objectid; | |
719 | found_end = key.objectid + key.offset; | |
720 | ASSERT(start >= found_start && end <= found_end); | |
721 | ||
722 | /* | |
723 | * Okay, now that we've found the free space extent which contains the | |
724 | * free space that we are removing, there are four cases: | |
725 | * | |
726 | * 1. We're using the whole extent: delete the key we found and | |
727 | * decrement the free space extent count. | |
728 | * 2. We are using part of the extent starting at the beginning: delete | |
729 | * the key we found and insert a new key representing the leftover at | |
730 | * the end. There is no net change in the number of extents. | |
731 | * 3. We are using part of the extent ending at the end: delete the key | |
732 | * we found and insert a new key representing the leftover at the | |
733 | * beginning. There is no net change in the number of extents. | |
734 | * 4. We are using part of the extent in the middle: delete the key we | |
735 | * found and insert two new keys representing the leftovers on each | |
736 | * side. Where we used to have one extent, we now have two, so increment | |
737 | * the extent count. We may need to convert the block group to bitmaps | |
738 | * as a result. | |
739 | */ | |
740 | ||
741 | /* Delete the existing key (cases 1-4). */ | |
742 | ret = btrfs_del_item(trans, root, path); | |
743 | if (ret) | |
744 | goto out; | |
745 | ||
746 | /* Add a key for leftovers at the beginning (cases 3 and 4). */ | |
747 | if (start > found_start) { | |
748 | key.objectid = found_start; | |
749 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
750 | key.offset = start - found_start; | |
751 | ||
752 | btrfs_release_path(path); | |
753 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
754 | if (ret) | |
755 | goto out; | |
756 | new_extents++; | |
757 | } | |
758 | ||
759 | /* Add a key for leftovers at the end (cases 2 and 4). */ | |
760 | if (end < found_end) { | |
761 | key.objectid = end; | |
762 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
763 | key.offset = found_end - end; | |
764 | ||
765 | btrfs_release_path(path); | |
766 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
767 | if (ret) | |
768 | goto out; | |
769 | new_extents++; | |
770 | } | |
771 | ||
772 | btrfs_release_path(path); | |
773 | ret = update_free_space_extent_count(trans, fs_info, block_group, path, | |
774 | new_extents); | |
775 | ||
776 | out: | |
777 | return ret; | |
778 | } | |
779 | ||
780 | int __remove_from_free_space_tree(struct btrfs_trans_handle *trans, | |
781 | struct btrfs_fs_info *fs_info, | |
782 | struct btrfs_block_group_cache *block_group, | |
783 | struct btrfs_path *path, u64 start, u64 size) | |
784 | { | |
785 | struct btrfs_free_space_info *info; | |
786 | u32 flags; | |
787 | int ret; | |
788 | ||
789 | if (block_group->needs_free_space) { | |
9a7e0f92 | 790 | ret = __add_block_group_free_space(trans, block_group, path); |
a5ed9182 OS |
791 | if (ret) |
792 | return ret; | |
793 | } | |
794 | ||
795 | info = search_free_space_info(NULL, fs_info, block_group, path, 0); | |
796 | if (IS_ERR(info)) | |
797 | return PTR_ERR(info); | |
798 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
799 | btrfs_release_path(path); | |
800 | ||
801 | if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { | |
802 | return modify_free_space_bitmap(trans, fs_info, block_group, | |
803 | path, start, size, 1); | |
804 | } else { | |
805 | return remove_free_space_extent(trans, fs_info, block_group, | |
806 | path, start, size); | |
807 | } | |
808 | } | |
809 | ||
810 | int remove_from_free_space_tree(struct btrfs_trans_handle *trans, | |
811 | struct btrfs_fs_info *fs_info, | |
812 | u64 start, u64 size) | |
813 | { | |
814 | struct btrfs_block_group_cache *block_group; | |
815 | struct btrfs_path *path; | |
816 | int ret; | |
817 | ||
818 | if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) | |
819 | return 0; | |
820 | ||
821 | path = btrfs_alloc_path(); | |
822 | if (!path) { | |
823 | ret = -ENOMEM; | |
824 | goto out; | |
825 | } | |
826 | ||
827 | block_group = btrfs_lookup_block_group(fs_info, start); | |
828 | if (!block_group) { | |
829 | ASSERT(0); | |
830 | ret = -ENOENT; | |
831 | goto out; | |
832 | } | |
833 | ||
834 | mutex_lock(&block_group->free_space_lock); | |
835 | ret = __remove_from_free_space_tree(trans, fs_info, block_group, path, | |
836 | start, size); | |
837 | mutex_unlock(&block_group->free_space_lock); | |
838 | ||
839 | btrfs_put_block_group(block_group); | |
840 | out: | |
841 | btrfs_free_path(path); | |
842 | if (ret) | |
66642832 | 843 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
844 | return ret; |
845 | } | |
846 | ||
847 | static int add_free_space_extent(struct btrfs_trans_handle *trans, | |
848 | struct btrfs_fs_info *fs_info, | |
849 | struct btrfs_block_group_cache *block_group, | |
850 | struct btrfs_path *path, | |
851 | u64 start, u64 size) | |
852 | { | |
853 | struct btrfs_root *root = fs_info->free_space_root; | |
854 | struct btrfs_key key, new_key; | |
855 | u64 found_start, found_end; | |
856 | u64 end = start + size; | |
857 | int new_extents = 1; | |
858 | int ret; | |
859 | ||
860 | /* | |
861 | * We are adding a new extent of free space, but we need to merge | |
862 | * extents. There are four cases here: | |
863 | * | |
864 | * 1. The new extent does not have any immediate neighbors to merge | |
865 | * with: add the new key and increment the free space extent count. We | |
866 | * may need to convert the block group to bitmaps as a result. | |
867 | * 2. The new extent has an immediate neighbor before it: remove the | |
868 | * previous key and insert a new key combining both of them. There is no | |
869 | * net change in the number of extents. | |
870 | * 3. The new extent has an immediate neighbor after it: remove the next | |
871 | * key and insert a new key combining both of them. There is no net | |
872 | * change in the number of extents. | |
873 | * 4. The new extent has immediate neighbors on both sides: remove both | |
874 | * of the keys and insert a new key combining all of them. Where we used | |
875 | * to have two extents, we now have one, so decrement the extent count. | |
876 | */ | |
877 | ||
878 | new_key.objectid = start; | |
879 | new_key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
880 | new_key.offset = size; | |
881 | ||
882 | /* Search for a neighbor on the left. */ | |
883 | if (start == block_group->key.objectid) | |
884 | goto right; | |
885 | key.objectid = start - 1; | |
886 | key.type = (u8)-1; | |
887 | key.offset = (u64)-1; | |
888 | ||
889 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
890 | if (ret) | |
891 | goto out; | |
892 | ||
893 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
894 | ||
895 | if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) { | |
896 | ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY); | |
897 | btrfs_release_path(path); | |
898 | goto right; | |
899 | } | |
900 | ||
901 | found_start = key.objectid; | |
902 | found_end = key.objectid + key.offset; | |
903 | ASSERT(found_start >= block_group->key.objectid && | |
904 | found_end > block_group->key.objectid); | |
905 | ASSERT(found_start < start && found_end <= start); | |
906 | ||
907 | /* | |
908 | * Delete the neighbor on the left and absorb it into the new key (cases | |
909 | * 2 and 4). | |
910 | */ | |
911 | if (found_end == start) { | |
912 | ret = btrfs_del_item(trans, root, path); | |
913 | if (ret) | |
914 | goto out; | |
915 | new_key.objectid = found_start; | |
916 | new_key.offset += key.offset; | |
917 | new_extents--; | |
918 | } | |
919 | btrfs_release_path(path); | |
920 | ||
921 | right: | |
922 | /* Search for a neighbor on the right. */ | |
923 | if (end == block_group->key.objectid + block_group->key.offset) | |
924 | goto insert; | |
925 | key.objectid = end; | |
926 | key.type = (u8)-1; | |
927 | key.offset = (u64)-1; | |
928 | ||
929 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
930 | if (ret) | |
931 | goto out; | |
932 | ||
933 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
934 | ||
935 | if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) { | |
936 | ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY); | |
937 | btrfs_release_path(path); | |
938 | goto insert; | |
939 | } | |
940 | ||
941 | found_start = key.objectid; | |
942 | found_end = key.objectid + key.offset; | |
943 | ASSERT(found_start >= block_group->key.objectid && | |
944 | found_end > block_group->key.objectid); | |
945 | ASSERT((found_start < start && found_end <= start) || | |
946 | (found_start >= end && found_end > end)); | |
947 | ||
948 | /* | |
949 | * Delete the neighbor on the right and absorb it into the new key | |
950 | * (cases 3 and 4). | |
951 | */ | |
952 | if (found_start == end) { | |
953 | ret = btrfs_del_item(trans, root, path); | |
954 | if (ret) | |
955 | goto out; | |
956 | new_key.offset += key.offset; | |
957 | new_extents--; | |
958 | } | |
959 | btrfs_release_path(path); | |
960 | ||
961 | insert: | |
962 | /* Insert the new key (cases 1-4). */ | |
963 | ret = btrfs_insert_empty_item(trans, root, path, &new_key, 0); | |
964 | if (ret) | |
965 | goto out; | |
966 | ||
967 | btrfs_release_path(path); | |
968 | ret = update_free_space_extent_count(trans, fs_info, block_group, path, | |
969 | new_extents); | |
970 | ||
971 | out: | |
972 | return ret; | |
973 | } | |
974 | ||
975 | int __add_to_free_space_tree(struct btrfs_trans_handle *trans, | |
a5ed9182 OS |
976 | struct btrfs_block_group_cache *block_group, |
977 | struct btrfs_path *path, u64 start, u64 size) | |
978 | { | |
2d5cffa1 | 979 | struct btrfs_fs_info *fs_info = trans->fs_info; |
a5ed9182 OS |
980 | struct btrfs_free_space_info *info; |
981 | u32 flags; | |
982 | int ret; | |
983 | ||
984 | if (block_group->needs_free_space) { | |
9a7e0f92 | 985 | ret = __add_block_group_free_space(trans, block_group, path); |
a5ed9182 OS |
986 | if (ret) |
987 | return ret; | |
988 | } | |
989 | ||
990 | info = search_free_space_info(NULL, fs_info, block_group, path, 0); | |
991 | if (IS_ERR(info)) | |
992 | return PTR_ERR(info); | |
993 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
994 | btrfs_release_path(path); | |
995 | ||
996 | if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { | |
997 | return modify_free_space_bitmap(trans, fs_info, block_group, | |
998 | path, start, size, 0); | |
999 | } else { | |
1000 | return add_free_space_extent(trans, fs_info, block_group, path, | |
1001 | start, size); | |
1002 | } | |
1003 | } | |
1004 | ||
1005 | int add_to_free_space_tree(struct btrfs_trans_handle *trans, | |
1006 | struct btrfs_fs_info *fs_info, | |
1007 | u64 start, u64 size) | |
1008 | { | |
1009 | struct btrfs_block_group_cache *block_group; | |
1010 | struct btrfs_path *path; | |
1011 | int ret; | |
1012 | ||
1013 | if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) | |
1014 | return 0; | |
1015 | ||
1016 | path = btrfs_alloc_path(); | |
1017 | if (!path) { | |
1018 | ret = -ENOMEM; | |
1019 | goto out; | |
1020 | } | |
1021 | ||
1022 | block_group = btrfs_lookup_block_group(fs_info, start); | |
1023 | if (!block_group) { | |
1024 | ASSERT(0); | |
1025 | ret = -ENOENT; | |
1026 | goto out; | |
1027 | } | |
1028 | ||
1029 | mutex_lock(&block_group->free_space_lock); | |
2d5cffa1 | 1030 | ret = __add_to_free_space_tree(trans, block_group, path, start, size); |
a5ed9182 OS |
1031 | mutex_unlock(&block_group->free_space_lock); |
1032 | ||
1033 | btrfs_put_block_group(block_group); | |
1034 | out: | |
1035 | btrfs_free_path(path); | |
1036 | if (ret) | |
66642832 | 1037 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
1038 | return ret; |
1039 | } | |
1040 | ||
1041 | /* | |
1042 | * Populate the free space tree by walking the extent tree. Operations on the | |
1043 | * extent tree that happen as a result of writes to the free space tree will go | |
1044 | * through the normal add/remove hooks. | |
1045 | */ | |
1046 | static int populate_free_space_tree(struct btrfs_trans_handle *trans, | |
1047 | struct btrfs_fs_info *fs_info, | |
1048 | struct btrfs_block_group_cache *block_group) | |
1049 | { | |
1050 | struct btrfs_root *extent_root = fs_info->extent_root; | |
1051 | struct btrfs_path *path, *path2; | |
1052 | struct btrfs_key key; | |
1053 | u64 start, end; | |
1054 | int ret; | |
1055 | ||
1056 | path = btrfs_alloc_path(); | |
1057 | if (!path) | |
1058 | return -ENOMEM; | |
019599ad | 1059 | path->reada = READA_FORWARD; |
a5ed9182 OS |
1060 | |
1061 | path2 = btrfs_alloc_path(); | |
1062 | if (!path2) { | |
1063 | btrfs_free_path(path); | |
1064 | return -ENOMEM; | |
1065 | } | |
1066 | ||
66afee18 | 1067 | ret = add_new_free_space_info(trans, block_group, path2); |
a5ed9182 OS |
1068 | if (ret) |
1069 | goto out; | |
1070 | ||
511711af CM |
1071 | mutex_lock(&block_group->free_space_lock); |
1072 | ||
a5ed9182 OS |
1073 | /* |
1074 | * Iterate through all of the extent and metadata items in this block | |
1075 | * group, adding the free space between them and the free space at the | |
1076 | * end. Note that EXTENT_ITEM and METADATA_ITEM are less than | |
1077 | * BLOCK_GROUP_ITEM, so an extent may precede the block group that it's | |
1078 | * contained in. | |
1079 | */ | |
1080 | key.objectid = block_group->key.objectid; | |
1081 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
1082 | key.offset = 0; | |
1083 | ||
1084 | ret = btrfs_search_slot_for_read(extent_root, &key, path, 1, 0); | |
1085 | if (ret < 0) | |
511711af | 1086 | goto out_locked; |
a5ed9182 OS |
1087 | ASSERT(ret == 0); |
1088 | ||
1089 | start = block_group->key.objectid; | |
1090 | end = block_group->key.objectid + block_group->key.offset; | |
1091 | while (1) { | |
1092 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1093 | ||
1094 | if (key.type == BTRFS_EXTENT_ITEM_KEY || | |
1095 | key.type == BTRFS_METADATA_ITEM_KEY) { | |
1096 | if (key.objectid >= end) | |
1097 | break; | |
1098 | ||
1099 | if (start < key.objectid) { | |
2d5cffa1 | 1100 | ret = __add_to_free_space_tree(trans, |
a5ed9182 OS |
1101 | block_group, |
1102 | path2, start, | |
1103 | key.objectid - | |
1104 | start); | |
1105 | if (ret) | |
511711af | 1106 | goto out_locked; |
a5ed9182 OS |
1107 | } |
1108 | start = key.objectid; | |
1109 | if (key.type == BTRFS_METADATA_ITEM_KEY) | |
da17066c | 1110 | start += fs_info->nodesize; |
a5ed9182 OS |
1111 | else |
1112 | start += key.offset; | |
1113 | } else if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) { | |
1114 | if (key.objectid != block_group->key.objectid) | |
1115 | break; | |
1116 | } | |
1117 | ||
1118 | ret = btrfs_next_item(extent_root, path); | |
1119 | if (ret < 0) | |
511711af | 1120 | goto out_locked; |
a5ed9182 OS |
1121 | if (ret) |
1122 | break; | |
1123 | } | |
1124 | if (start < end) { | |
2d5cffa1 NB |
1125 | ret = __add_to_free_space_tree(trans, block_group, path2, |
1126 | start, end - start); | |
a5ed9182 | 1127 | if (ret) |
511711af | 1128 | goto out_locked; |
a5ed9182 OS |
1129 | } |
1130 | ||
1131 | ret = 0; | |
511711af CM |
1132 | out_locked: |
1133 | mutex_unlock(&block_group->free_space_lock); | |
a5ed9182 OS |
1134 | out: |
1135 | btrfs_free_path(path2); | |
1136 | btrfs_free_path(path); | |
1137 | return ret; | |
1138 | } | |
1139 | ||
1140 | int btrfs_create_free_space_tree(struct btrfs_fs_info *fs_info) | |
1141 | { | |
1142 | struct btrfs_trans_handle *trans; | |
1143 | struct btrfs_root *tree_root = fs_info->tree_root; | |
1144 | struct btrfs_root *free_space_root; | |
1145 | struct btrfs_block_group_cache *block_group; | |
1146 | struct rb_node *node; | |
1147 | int ret; | |
1148 | ||
1149 | trans = btrfs_start_transaction(tree_root, 0); | |
1150 | if (IS_ERR(trans)) | |
1151 | return PTR_ERR(trans); | |
1152 | ||
afcdd129 | 1153 | set_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); |
a5ed9182 OS |
1154 | free_space_root = btrfs_create_tree(trans, fs_info, |
1155 | BTRFS_FREE_SPACE_TREE_OBJECTID); | |
1156 | if (IS_ERR(free_space_root)) { | |
1157 | ret = PTR_ERR(free_space_root); | |
1158 | goto abort; | |
1159 | } | |
1160 | fs_info->free_space_root = free_space_root; | |
1161 | ||
1162 | node = rb_first(&fs_info->block_group_cache_tree); | |
1163 | while (node) { | |
1164 | block_group = rb_entry(node, struct btrfs_block_group_cache, | |
1165 | cache_node); | |
1166 | ret = populate_free_space_tree(trans, fs_info, block_group); | |
1167 | if (ret) | |
1168 | goto abort; | |
1169 | node = rb_next(node); | |
1170 | } | |
1171 | ||
1172 | btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE); | |
6675df31 | 1173 | btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); |
afcdd129 | 1174 | clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); |
a5ed9182 | 1175 | |
0bef7109 | 1176 | return btrfs_commit_transaction(trans); |
a5ed9182 OS |
1177 | |
1178 | abort: | |
afcdd129 | 1179 | clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); |
66642832 | 1180 | btrfs_abort_transaction(trans, ret); |
3a45bb20 | 1181 | btrfs_end_transaction(trans); |
a5ed9182 OS |
1182 | return ret; |
1183 | } | |
1184 | ||
1185 | static int clear_free_space_tree(struct btrfs_trans_handle *trans, | |
1186 | struct btrfs_root *root) | |
1187 | { | |
1188 | struct btrfs_path *path; | |
1189 | struct btrfs_key key; | |
1190 | int nr; | |
1191 | int ret; | |
1192 | ||
1193 | path = btrfs_alloc_path(); | |
1194 | if (!path) | |
1195 | return -ENOMEM; | |
1196 | ||
1197 | path->leave_spinning = 1; | |
1198 | ||
1199 | key.objectid = 0; | |
1200 | key.type = 0; | |
1201 | key.offset = 0; | |
1202 | ||
1203 | while (1) { | |
1204 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
1205 | if (ret < 0) | |
1206 | goto out; | |
1207 | ||
1208 | nr = btrfs_header_nritems(path->nodes[0]); | |
1209 | if (!nr) | |
1210 | break; | |
1211 | ||
1212 | path->slots[0] = 0; | |
1213 | ret = btrfs_del_items(trans, root, path, 0, nr); | |
1214 | if (ret) | |
1215 | goto out; | |
1216 | ||
1217 | btrfs_release_path(path); | |
1218 | } | |
1219 | ||
1220 | ret = 0; | |
1221 | out: | |
1222 | btrfs_free_path(path); | |
1223 | return ret; | |
1224 | } | |
1225 | ||
1226 | int btrfs_clear_free_space_tree(struct btrfs_fs_info *fs_info) | |
1227 | { | |
1228 | struct btrfs_trans_handle *trans; | |
1229 | struct btrfs_root *tree_root = fs_info->tree_root; | |
1230 | struct btrfs_root *free_space_root = fs_info->free_space_root; | |
1231 | int ret; | |
1232 | ||
1233 | trans = btrfs_start_transaction(tree_root, 0); | |
1234 | if (IS_ERR(trans)) | |
1235 | return PTR_ERR(trans); | |
1236 | ||
1237 | btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE); | |
6675df31 | 1238 | btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); |
a5ed9182 OS |
1239 | fs_info->free_space_root = NULL; |
1240 | ||
1241 | ret = clear_free_space_tree(trans, free_space_root); | |
1242 | if (ret) | |
1243 | goto abort; | |
1244 | ||
1cd5447e | 1245 | ret = btrfs_del_root(trans, fs_info, &free_space_root->root_key); |
a5ed9182 OS |
1246 | if (ret) |
1247 | goto abort; | |
1248 | ||
1249 | list_del(&free_space_root->dirty_list); | |
1250 | ||
1251 | btrfs_tree_lock(free_space_root->node); | |
7c302b49 | 1252 | clean_tree_block(fs_info, free_space_root->node); |
a5ed9182 OS |
1253 | btrfs_tree_unlock(free_space_root->node); |
1254 | btrfs_free_tree_block(trans, free_space_root, free_space_root->node, | |
1255 | 0, 1); | |
1256 | ||
1257 | free_extent_buffer(free_space_root->node); | |
1258 | free_extent_buffer(free_space_root->commit_root); | |
1259 | kfree(free_space_root); | |
1260 | ||
0bef7109 | 1261 | return btrfs_commit_transaction(trans); |
a5ed9182 OS |
1262 | |
1263 | abort: | |
66642832 | 1264 | btrfs_abort_transaction(trans, ret); |
3a45bb20 | 1265 | btrfs_end_transaction(trans); |
a5ed9182 OS |
1266 | return ret; |
1267 | } | |
1268 | ||
1269 | static int __add_block_group_free_space(struct btrfs_trans_handle *trans, | |
a5ed9182 OS |
1270 | struct btrfs_block_group_cache *block_group, |
1271 | struct btrfs_path *path) | |
1272 | { | |
a5ed9182 OS |
1273 | int ret; |
1274 | ||
a5ed9182 OS |
1275 | block_group->needs_free_space = 0; |
1276 | ||
66afee18 | 1277 | ret = add_new_free_space_info(trans, block_group, path); |
a5ed9182 OS |
1278 | if (ret) |
1279 | return ret; | |
1280 | ||
2d5cffa1 | 1281 | return __add_to_free_space_tree(trans, block_group, path, |
a5ed9182 OS |
1282 | block_group->key.objectid, |
1283 | block_group->key.offset); | |
1284 | } | |
1285 | ||
1286 | int add_block_group_free_space(struct btrfs_trans_handle *trans, | |
a5ed9182 OS |
1287 | struct btrfs_block_group_cache *block_group) |
1288 | { | |
e4e0711c | 1289 | struct btrfs_fs_info *fs_info = trans->fs_info; |
a5ed9182 OS |
1290 | struct btrfs_path *path = NULL; |
1291 | int ret = 0; | |
1292 | ||
1293 | if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) | |
1294 | return 0; | |
1295 | ||
1296 | mutex_lock(&block_group->free_space_lock); | |
1297 | if (!block_group->needs_free_space) | |
1298 | goto out; | |
1299 | ||
1300 | path = btrfs_alloc_path(); | |
1301 | if (!path) { | |
1302 | ret = -ENOMEM; | |
1303 | goto out; | |
1304 | } | |
1305 | ||
9a7e0f92 | 1306 | ret = __add_block_group_free_space(trans, block_group, path); |
a5ed9182 OS |
1307 | |
1308 | out: | |
1309 | btrfs_free_path(path); | |
1310 | mutex_unlock(&block_group->free_space_lock); | |
1311 | if (ret) | |
66642832 | 1312 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
1313 | return ret; |
1314 | } | |
1315 | ||
1316 | int remove_block_group_free_space(struct btrfs_trans_handle *trans, | |
a5ed9182 OS |
1317 | struct btrfs_block_group_cache *block_group) |
1318 | { | |
f3f72779 | 1319 | struct btrfs_root *root = trans->fs_info->free_space_root; |
a5ed9182 OS |
1320 | struct btrfs_path *path; |
1321 | struct btrfs_key key, found_key; | |
1322 | struct extent_buffer *leaf; | |
1323 | u64 start, end; | |
1324 | int done = 0, nr; | |
1325 | int ret; | |
1326 | ||
f3f72779 | 1327 | if (!btrfs_fs_compat_ro(trans->fs_info, FREE_SPACE_TREE)) |
a5ed9182 OS |
1328 | return 0; |
1329 | ||
1330 | if (block_group->needs_free_space) { | |
1331 | /* We never added this block group to the free space tree. */ | |
1332 | return 0; | |
1333 | } | |
1334 | ||
1335 | path = btrfs_alloc_path(); | |
1336 | if (!path) { | |
1337 | ret = -ENOMEM; | |
1338 | goto out; | |
1339 | } | |
1340 | ||
1341 | start = block_group->key.objectid; | |
1342 | end = block_group->key.objectid + block_group->key.offset; | |
1343 | ||
1344 | key.objectid = end - 1; | |
1345 | key.type = (u8)-1; | |
1346 | key.offset = (u64)-1; | |
1347 | ||
1348 | while (!done) { | |
1349 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
1350 | if (ret) | |
1351 | goto out; | |
1352 | ||
1353 | leaf = path->nodes[0]; | |
1354 | nr = 0; | |
1355 | path->slots[0]++; | |
1356 | while (path->slots[0] > 0) { | |
1357 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); | |
1358 | ||
1359 | if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { | |
1360 | ASSERT(found_key.objectid == block_group->key.objectid); | |
1361 | ASSERT(found_key.offset == block_group->key.offset); | |
1362 | done = 1; | |
1363 | nr++; | |
1364 | path->slots[0]--; | |
1365 | break; | |
1366 | } else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY || | |
1367 | found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) { | |
1368 | ASSERT(found_key.objectid >= start); | |
1369 | ASSERT(found_key.objectid < end); | |
1370 | ASSERT(found_key.objectid + found_key.offset <= end); | |
1371 | nr++; | |
1372 | path->slots[0]--; | |
1373 | } else { | |
1374 | ASSERT(0); | |
1375 | } | |
1376 | } | |
1377 | ||
1378 | ret = btrfs_del_items(trans, root, path, path->slots[0], nr); | |
1379 | if (ret) | |
1380 | goto out; | |
1381 | btrfs_release_path(path); | |
1382 | } | |
1383 | ||
1384 | ret = 0; | |
1385 | out: | |
1386 | btrfs_free_path(path); | |
1387 | if (ret) | |
66642832 | 1388 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
1389 | return ret; |
1390 | } | |
1391 | ||
1392 | static int load_free_space_bitmaps(struct btrfs_caching_control *caching_ctl, | |
1393 | struct btrfs_path *path, | |
1394 | u32 expected_extent_count) | |
1395 | { | |
1396 | struct btrfs_block_group_cache *block_group; | |
1397 | struct btrfs_fs_info *fs_info; | |
1398 | struct btrfs_root *root; | |
1399 | struct btrfs_key key; | |
1400 | int prev_bit = 0, bit; | |
1401 | /* Initialize to silence GCC. */ | |
1402 | u64 extent_start = 0; | |
1403 | u64 end, offset; | |
1404 | u64 total_found = 0; | |
1405 | u32 extent_count = 0; | |
1406 | int ret; | |
1407 | ||
1408 | block_group = caching_ctl->block_group; | |
1409 | fs_info = block_group->fs_info; | |
1410 | root = fs_info->free_space_root; | |
1411 | ||
1412 | end = block_group->key.objectid + block_group->key.offset; | |
1413 | ||
1414 | while (1) { | |
1415 | ret = btrfs_next_item(root, path); | |
1416 | if (ret < 0) | |
1417 | goto out; | |
1418 | if (ret) | |
1419 | break; | |
1420 | ||
1421 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1422 | ||
1423 | if (key.type == BTRFS_FREE_SPACE_INFO_KEY) | |
1424 | break; | |
1425 | ||
1426 | ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); | |
1427 | ASSERT(key.objectid < end && key.objectid + key.offset <= end); | |
1428 | ||
1429 | caching_ctl->progress = key.objectid; | |
1430 | ||
1431 | offset = key.objectid; | |
1432 | while (offset < key.objectid + key.offset) { | |
1433 | bit = free_space_test_bit(block_group, path, offset); | |
1434 | if (prev_bit == 0 && bit == 1) { | |
1435 | extent_start = offset; | |
1436 | } else if (prev_bit == 1 && bit == 0) { | |
1437 | total_found += add_new_free_space(block_group, | |
a5ed9182 OS |
1438 | extent_start, |
1439 | offset); | |
1440 | if (total_found > CACHING_CTL_WAKE_UP) { | |
1441 | total_found = 0; | |
1442 | wake_up(&caching_ctl->wait); | |
1443 | } | |
1444 | extent_count++; | |
1445 | } | |
1446 | prev_bit = bit; | |
0b246afa | 1447 | offset += fs_info->sectorsize; |
a5ed9182 OS |
1448 | } |
1449 | } | |
1450 | if (prev_bit == 1) { | |
4457c1c7 NB |
1451 | total_found += add_new_free_space(block_group, extent_start, |
1452 | end); | |
a5ed9182 OS |
1453 | extent_count++; |
1454 | } | |
1455 | ||
1456 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
1457 | btrfs_err(fs_info, |
1458 | "incorrect extent count for %llu; counted %u, expected %u", | |
a5ed9182 OS |
1459 | block_group->key.objectid, extent_count, |
1460 | expected_extent_count); | |
1461 | ASSERT(0); | |
1462 | ret = -EIO; | |
1463 | goto out; | |
1464 | } | |
1465 | ||
1466 | caching_ctl->progress = (u64)-1; | |
1467 | ||
1468 | ret = 0; | |
1469 | out: | |
1470 | return ret; | |
1471 | } | |
1472 | ||
1473 | static int load_free_space_extents(struct btrfs_caching_control *caching_ctl, | |
1474 | struct btrfs_path *path, | |
1475 | u32 expected_extent_count) | |
1476 | { | |
1477 | struct btrfs_block_group_cache *block_group; | |
1478 | struct btrfs_fs_info *fs_info; | |
1479 | struct btrfs_root *root; | |
1480 | struct btrfs_key key; | |
1481 | u64 end; | |
1482 | u64 total_found = 0; | |
1483 | u32 extent_count = 0; | |
1484 | int ret; | |
1485 | ||
1486 | block_group = caching_ctl->block_group; | |
1487 | fs_info = block_group->fs_info; | |
1488 | root = fs_info->free_space_root; | |
1489 | ||
1490 | end = block_group->key.objectid + block_group->key.offset; | |
1491 | ||
1492 | while (1) { | |
1493 | ret = btrfs_next_item(root, path); | |
1494 | if (ret < 0) | |
1495 | goto out; | |
1496 | if (ret) | |
1497 | break; | |
1498 | ||
1499 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1500 | ||
1501 | if (key.type == BTRFS_FREE_SPACE_INFO_KEY) | |
1502 | break; | |
1503 | ||
1504 | ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY); | |
1505 | ASSERT(key.objectid < end && key.objectid + key.offset <= end); | |
1506 | ||
1507 | caching_ctl->progress = key.objectid; | |
1508 | ||
4457c1c7 | 1509 | total_found += add_new_free_space(block_group, key.objectid, |
a5ed9182 OS |
1510 | key.objectid + key.offset); |
1511 | if (total_found > CACHING_CTL_WAKE_UP) { | |
1512 | total_found = 0; | |
1513 | wake_up(&caching_ctl->wait); | |
1514 | } | |
1515 | extent_count++; | |
1516 | } | |
1517 | ||
1518 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
1519 | btrfs_err(fs_info, |
1520 | "incorrect extent count for %llu; counted %u, expected %u", | |
a5ed9182 OS |
1521 | block_group->key.objectid, extent_count, |
1522 | expected_extent_count); | |
1523 | ASSERT(0); | |
1524 | ret = -EIO; | |
1525 | goto out; | |
1526 | } | |
1527 | ||
1528 | caching_ctl->progress = (u64)-1; | |
1529 | ||
1530 | ret = 0; | |
1531 | out: | |
1532 | return ret; | |
1533 | } | |
1534 | ||
1535 | int load_free_space_tree(struct btrfs_caching_control *caching_ctl) | |
1536 | { | |
1537 | struct btrfs_block_group_cache *block_group; | |
1538 | struct btrfs_fs_info *fs_info; | |
1539 | struct btrfs_free_space_info *info; | |
1540 | struct btrfs_path *path; | |
1541 | u32 extent_count, flags; | |
1542 | int ret; | |
1543 | ||
1544 | block_group = caching_ctl->block_group; | |
1545 | fs_info = block_group->fs_info; | |
1546 | ||
1547 | path = btrfs_alloc_path(); | |
1548 | if (!path) | |
1549 | return -ENOMEM; | |
1550 | ||
1551 | /* | |
1552 | * Just like caching_thread() doesn't want to deadlock on the extent | |
1553 | * tree, we don't want to deadlock on the free space tree. | |
1554 | */ | |
1555 | path->skip_locking = 1; | |
1556 | path->search_commit_root = 1; | |
7ce311d5 | 1557 | path->reada = READA_FORWARD; |
a5ed9182 OS |
1558 | |
1559 | info = search_free_space_info(NULL, fs_info, block_group, path, 0); | |
1560 | if (IS_ERR(info)) { | |
1561 | ret = PTR_ERR(info); | |
1562 | goto out; | |
1563 | } | |
1564 | extent_count = btrfs_free_space_extent_count(path->nodes[0], info); | |
1565 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
1566 | ||
1567 | /* | |
1568 | * We left path pointing to the free space info item, so now | |
1569 | * load_free_space_foo can just iterate through the free space tree from | |
1570 | * there. | |
1571 | */ | |
1572 | if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) | |
1573 | ret = load_free_space_bitmaps(caching_ctl, path, extent_count); | |
1574 | else | |
1575 | ret = load_free_space_extents(caching_ctl, path, extent_count); | |
1576 | ||
1577 | out: | |
1578 | btrfs_free_path(path); | |
1579 | return ret; | |
1580 | } |