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a5ed9182 OS |
1 | /* |
2 | * Copyright (C) 2015 Facebook. All rights reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public | |
6 | * License v2 as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public | |
14 | * License along with this program; if not, write to the | |
15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
16 | * Boston, MA 021110-1307, USA. | |
17 | */ | |
18 | ||
19 | #include <linux/kernel.h> | |
20 | #include <linux/vmalloc.h> | |
21 | #include "ctree.h" | |
22 | #include "disk-io.h" | |
23 | #include "locking.h" | |
24 | #include "free-space-tree.h" | |
25 | #include "transaction.h" | |
26 | ||
27 | static int __add_block_group_free_space(struct btrfs_trans_handle *trans, | |
28 | struct btrfs_fs_info *fs_info, | |
29 | struct btrfs_block_group_cache *block_group, | |
30 | struct btrfs_path *path); | |
31 | ||
32 | void set_free_space_tree_thresholds(struct btrfs_block_group_cache *cache) | |
33 | { | |
34 | u32 bitmap_range; | |
35 | size_t bitmap_size; | |
36 | u64 num_bitmaps, total_bitmap_size; | |
37 | ||
38 | /* | |
39 | * We convert to bitmaps when the disk space required for using extents | |
40 | * exceeds that required for using bitmaps. | |
41 | */ | |
da17066c | 42 | bitmap_range = cache->fs_info->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS; |
a5ed9182 OS |
43 | num_bitmaps = div_u64(cache->key.offset + bitmap_range - 1, |
44 | bitmap_range); | |
45 | bitmap_size = sizeof(struct btrfs_item) + BTRFS_FREE_SPACE_BITMAP_SIZE; | |
46 | total_bitmap_size = num_bitmaps * bitmap_size; | |
47 | cache->bitmap_high_thresh = div_u64(total_bitmap_size, | |
48 | sizeof(struct btrfs_item)); | |
49 | ||
50 | /* | |
51 | * We allow for a small buffer between the high threshold and low | |
52 | * threshold to avoid thrashing back and forth between the two formats. | |
53 | */ | |
54 | if (cache->bitmap_high_thresh > 100) | |
55 | cache->bitmap_low_thresh = cache->bitmap_high_thresh - 100; | |
56 | else | |
57 | cache->bitmap_low_thresh = 0; | |
58 | } | |
59 | ||
60 | static int add_new_free_space_info(struct btrfs_trans_handle *trans, | |
61 | struct btrfs_fs_info *fs_info, | |
62 | struct btrfs_block_group_cache *block_group, | |
63 | struct btrfs_path *path) | |
64 | { | |
65 | struct btrfs_root *root = fs_info->free_space_root; | |
66 | struct btrfs_free_space_info *info; | |
67 | struct btrfs_key key; | |
68 | struct extent_buffer *leaf; | |
69 | int ret; | |
70 | ||
71 | key.objectid = block_group->key.objectid; | |
72 | key.type = BTRFS_FREE_SPACE_INFO_KEY; | |
73 | key.offset = block_group->key.offset; | |
74 | ||
75 | ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*info)); | |
76 | if (ret) | |
77 | goto out; | |
78 | ||
79 | leaf = path->nodes[0]; | |
80 | info = btrfs_item_ptr(leaf, path->slots[0], | |
81 | struct btrfs_free_space_info); | |
82 | btrfs_set_free_space_extent_count(leaf, info, 0); | |
83 | btrfs_set_free_space_flags(leaf, info, 0); | |
84 | btrfs_mark_buffer_dirty(leaf); | |
85 | ||
86 | ret = 0; | |
87 | out: | |
88 | btrfs_release_path(path); | |
89 | return ret; | |
90 | } | |
91 | ||
92 | struct btrfs_free_space_info * | |
93 | search_free_space_info(struct btrfs_trans_handle *trans, | |
94 | struct btrfs_fs_info *fs_info, | |
95 | struct btrfs_block_group_cache *block_group, | |
96 | struct btrfs_path *path, int cow) | |
97 | { | |
98 | struct btrfs_root *root = fs_info->free_space_root; | |
99 | struct btrfs_key key; | |
100 | int ret; | |
101 | ||
102 | key.objectid = block_group->key.objectid; | |
103 | key.type = BTRFS_FREE_SPACE_INFO_KEY; | |
104 | key.offset = block_group->key.offset; | |
105 | ||
106 | ret = btrfs_search_slot(trans, root, &key, path, 0, cow); | |
107 | if (ret < 0) | |
108 | return ERR_PTR(ret); | |
109 | if (ret != 0) { | |
ab8d0fc4 | 110 | btrfs_warn(fs_info, "missing free space info for %llu", |
a5ed9182 OS |
111 | block_group->key.objectid); |
112 | ASSERT(0); | |
113 | return ERR_PTR(-ENOENT); | |
114 | } | |
115 | ||
116 | return btrfs_item_ptr(path->nodes[0], path->slots[0], | |
117 | struct btrfs_free_space_info); | |
118 | } | |
119 | ||
120 | /* | |
121 | * btrfs_search_slot() but we're looking for the greatest key less than the | |
122 | * passed key. | |
123 | */ | |
124 | static int btrfs_search_prev_slot(struct btrfs_trans_handle *trans, | |
125 | struct btrfs_root *root, | |
126 | struct btrfs_key *key, struct btrfs_path *p, | |
127 | int ins_len, int cow) | |
128 | { | |
129 | int ret; | |
130 | ||
131 | ret = btrfs_search_slot(trans, root, key, p, ins_len, cow); | |
132 | if (ret < 0) | |
133 | return ret; | |
134 | ||
135 | if (ret == 0) { | |
136 | ASSERT(0); | |
137 | return -EIO; | |
138 | } | |
139 | ||
140 | if (p->slots[0] == 0) { | |
141 | ASSERT(0); | |
142 | return -EIO; | |
143 | } | |
144 | p->slots[0]--; | |
145 | ||
146 | return 0; | |
147 | } | |
148 | ||
149 | static inline u32 free_space_bitmap_size(u64 size, u32 sectorsize) | |
150 | { | |
151 | return DIV_ROUND_UP((u32)div_u64(size, sectorsize), BITS_PER_BYTE); | |
152 | } | |
153 | ||
2fe1d551 | 154 | static u8 *alloc_bitmap(u32 bitmap_size) |
a5ed9182 | 155 | { |
79b134a2 DS |
156 | void *mem; |
157 | ||
158 | /* | |
159 | * The allocation size varies, observed numbers were < 4K up to 16K. | |
160 | * Using vmalloc unconditionally would be too heavy, we'll try | |
161 | * contiguous allocations first. | |
162 | */ | |
163 | if (bitmap_size <= PAGE_SIZE) | |
164 | return kzalloc(bitmap_size, GFP_NOFS); | |
165 | ||
e1c0ebad | 166 | mem = kzalloc(bitmap_size, GFP_NOFS | __GFP_NOWARN); |
79b134a2 DS |
167 | if (mem) |
168 | return mem; | |
169 | ||
a5ed9182 OS |
170 | return __vmalloc(bitmap_size, GFP_NOFS | __GFP_HIGHMEM | __GFP_ZERO, |
171 | PAGE_KERNEL); | |
172 | } | |
173 | ||
174 | int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans, | |
175 | struct btrfs_fs_info *fs_info, | |
176 | struct btrfs_block_group_cache *block_group, | |
177 | struct btrfs_path *path) | |
178 | { | |
179 | struct btrfs_root *root = fs_info->free_space_root; | |
180 | struct btrfs_free_space_info *info; | |
181 | struct btrfs_key key, found_key; | |
182 | struct extent_buffer *leaf; | |
2fe1d551 | 183 | u8 *bitmap, *bitmap_cursor; |
a5ed9182 OS |
184 | u64 start, end; |
185 | u64 bitmap_range, i; | |
186 | u32 bitmap_size, flags, expected_extent_count; | |
187 | u32 extent_count = 0; | |
188 | int done = 0, nr; | |
189 | int ret; | |
190 | ||
191 | bitmap_size = free_space_bitmap_size(block_group->key.offset, | |
0b246afa | 192 | fs_info->sectorsize); |
a5ed9182 OS |
193 | bitmap = alloc_bitmap(bitmap_size); |
194 | if (!bitmap) { | |
195 | ret = -ENOMEM; | |
196 | goto out; | |
197 | } | |
198 | ||
199 | start = block_group->key.objectid; | |
200 | end = block_group->key.objectid + block_group->key.offset; | |
201 | ||
202 | key.objectid = end - 1; | |
203 | key.type = (u8)-1; | |
204 | key.offset = (u64)-1; | |
205 | ||
206 | while (!done) { | |
207 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
208 | if (ret) | |
209 | goto out; | |
210 | ||
211 | leaf = path->nodes[0]; | |
212 | nr = 0; | |
213 | path->slots[0]++; | |
214 | while (path->slots[0] > 0) { | |
215 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); | |
216 | ||
217 | if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { | |
218 | ASSERT(found_key.objectid == block_group->key.objectid); | |
219 | ASSERT(found_key.offset == block_group->key.offset); | |
220 | done = 1; | |
221 | break; | |
222 | } else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY) { | |
223 | u64 first, last; | |
224 | ||
225 | ASSERT(found_key.objectid >= start); | |
226 | ASSERT(found_key.objectid < end); | |
227 | ASSERT(found_key.objectid + found_key.offset <= end); | |
228 | ||
229 | first = div_u64(found_key.objectid - start, | |
0b246afa | 230 | fs_info->sectorsize); |
a5ed9182 | 231 | last = div_u64(found_key.objectid + found_key.offset - start, |
0b246afa | 232 | fs_info->sectorsize); |
2fe1d551 | 233 | le_bitmap_set(bitmap, first, last - first); |
a5ed9182 OS |
234 | |
235 | extent_count++; | |
236 | nr++; | |
237 | path->slots[0]--; | |
238 | } else { | |
239 | ASSERT(0); | |
240 | } | |
241 | } | |
242 | ||
243 | ret = btrfs_del_items(trans, root, path, path->slots[0], nr); | |
244 | if (ret) | |
245 | goto out; | |
246 | btrfs_release_path(path); | |
247 | } | |
248 | ||
249 | info = search_free_space_info(trans, fs_info, block_group, path, 1); | |
250 | if (IS_ERR(info)) { | |
251 | ret = PTR_ERR(info); | |
252 | goto out; | |
253 | } | |
254 | leaf = path->nodes[0]; | |
255 | flags = btrfs_free_space_flags(leaf, info); | |
256 | flags |= BTRFS_FREE_SPACE_USING_BITMAPS; | |
257 | btrfs_set_free_space_flags(leaf, info, flags); | |
258 | expected_extent_count = btrfs_free_space_extent_count(leaf, info); | |
259 | btrfs_mark_buffer_dirty(leaf); | |
260 | btrfs_release_path(path); | |
261 | ||
262 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
263 | btrfs_err(fs_info, |
264 | "incorrect extent count for %llu; counted %u, expected %u", | |
a5ed9182 OS |
265 | block_group->key.objectid, extent_count, |
266 | expected_extent_count); | |
267 | ASSERT(0); | |
268 | ret = -EIO; | |
269 | goto out; | |
270 | } | |
271 | ||
2fe1d551 | 272 | bitmap_cursor = bitmap; |
0b246afa | 273 | bitmap_range = fs_info->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS; |
a5ed9182 OS |
274 | i = start; |
275 | while (i < end) { | |
276 | unsigned long ptr; | |
277 | u64 extent_size; | |
278 | u32 data_size; | |
279 | ||
280 | extent_size = min(end - i, bitmap_range); | |
281 | data_size = free_space_bitmap_size(extent_size, | |
0b246afa | 282 | fs_info->sectorsize); |
a5ed9182 OS |
283 | |
284 | key.objectid = i; | |
285 | key.type = BTRFS_FREE_SPACE_BITMAP_KEY; | |
286 | key.offset = extent_size; | |
287 | ||
288 | ret = btrfs_insert_empty_item(trans, root, path, &key, | |
289 | data_size); | |
290 | if (ret) | |
291 | goto out; | |
292 | ||
293 | leaf = path->nodes[0]; | |
294 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
295 | write_extent_buffer(leaf, bitmap_cursor, ptr, | |
296 | data_size); | |
297 | btrfs_mark_buffer_dirty(leaf); | |
298 | btrfs_release_path(path); | |
299 | ||
300 | i += extent_size; | |
301 | bitmap_cursor += data_size; | |
302 | } | |
303 | ||
304 | ret = 0; | |
305 | out: | |
79b134a2 | 306 | kvfree(bitmap); |
a5ed9182 | 307 | if (ret) |
66642832 | 308 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
309 | return ret; |
310 | } | |
311 | ||
312 | int convert_free_space_to_extents(struct btrfs_trans_handle *trans, | |
313 | struct btrfs_fs_info *fs_info, | |
314 | struct btrfs_block_group_cache *block_group, | |
315 | struct btrfs_path *path) | |
316 | { | |
317 | struct btrfs_root *root = fs_info->free_space_root; | |
318 | struct btrfs_free_space_info *info; | |
319 | struct btrfs_key key, found_key; | |
320 | struct extent_buffer *leaf; | |
2fe1d551 | 321 | u8 *bitmap; |
a5ed9182 OS |
322 | u64 start, end; |
323 | /* Initialize to silence GCC. */ | |
324 | u64 extent_start = 0; | |
325 | u64 offset; | |
326 | u32 bitmap_size, flags, expected_extent_count; | |
327 | int prev_bit = 0, bit, bitnr; | |
328 | u32 extent_count = 0; | |
329 | int done = 0, nr; | |
330 | int ret; | |
331 | ||
332 | bitmap_size = free_space_bitmap_size(block_group->key.offset, | |
0b246afa | 333 | fs_info->sectorsize); |
a5ed9182 OS |
334 | bitmap = alloc_bitmap(bitmap_size); |
335 | if (!bitmap) { | |
336 | ret = -ENOMEM; | |
337 | goto out; | |
338 | } | |
339 | ||
340 | start = block_group->key.objectid; | |
341 | end = block_group->key.objectid + block_group->key.offset; | |
342 | ||
343 | key.objectid = end - 1; | |
344 | key.type = (u8)-1; | |
345 | key.offset = (u64)-1; | |
346 | ||
347 | while (!done) { | |
348 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
349 | if (ret) | |
350 | goto out; | |
351 | ||
352 | leaf = path->nodes[0]; | |
353 | nr = 0; | |
354 | path->slots[0]++; | |
355 | while (path->slots[0] > 0) { | |
356 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); | |
357 | ||
358 | if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { | |
359 | ASSERT(found_key.objectid == block_group->key.objectid); | |
360 | ASSERT(found_key.offset == block_group->key.offset); | |
361 | done = 1; | |
362 | break; | |
363 | } else if (found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) { | |
364 | unsigned long ptr; | |
2fe1d551 | 365 | u8 *bitmap_cursor; |
a5ed9182 OS |
366 | u32 bitmap_pos, data_size; |
367 | ||
368 | ASSERT(found_key.objectid >= start); | |
369 | ASSERT(found_key.objectid < end); | |
370 | ASSERT(found_key.objectid + found_key.offset <= end); | |
371 | ||
372 | bitmap_pos = div_u64(found_key.objectid - start, | |
0b246afa | 373 | fs_info->sectorsize * |
a5ed9182 | 374 | BITS_PER_BYTE); |
2fe1d551 | 375 | bitmap_cursor = bitmap + bitmap_pos; |
a5ed9182 | 376 | data_size = free_space_bitmap_size(found_key.offset, |
0b246afa | 377 | fs_info->sectorsize); |
a5ed9182 OS |
378 | |
379 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0] - 1); | |
380 | read_extent_buffer(leaf, bitmap_cursor, ptr, | |
381 | data_size); | |
382 | ||
383 | nr++; | |
384 | path->slots[0]--; | |
385 | } else { | |
386 | ASSERT(0); | |
387 | } | |
388 | } | |
389 | ||
390 | ret = btrfs_del_items(trans, root, path, path->slots[0], nr); | |
391 | if (ret) | |
392 | goto out; | |
393 | btrfs_release_path(path); | |
394 | } | |
395 | ||
396 | info = search_free_space_info(trans, fs_info, block_group, path, 1); | |
397 | if (IS_ERR(info)) { | |
398 | ret = PTR_ERR(info); | |
399 | goto out; | |
400 | } | |
401 | leaf = path->nodes[0]; | |
402 | flags = btrfs_free_space_flags(leaf, info); | |
403 | flags &= ~BTRFS_FREE_SPACE_USING_BITMAPS; | |
404 | btrfs_set_free_space_flags(leaf, info, flags); | |
405 | expected_extent_count = btrfs_free_space_extent_count(leaf, info); | |
406 | btrfs_mark_buffer_dirty(leaf); | |
407 | btrfs_release_path(path); | |
408 | ||
409 | offset = start; | |
410 | bitnr = 0; | |
411 | while (offset < end) { | |
2fe1d551 | 412 | bit = !!le_test_bit(bitnr, bitmap); |
a5ed9182 OS |
413 | if (prev_bit == 0 && bit == 1) { |
414 | extent_start = offset; | |
415 | } else if (prev_bit == 1 && bit == 0) { | |
416 | key.objectid = extent_start; | |
417 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
418 | key.offset = offset - extent_start; | |
419 | ||
420 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
421 | if (ret) | |
422 | goto out; | |
423 | btrfs_release_path(path); | |
424 | ||
425 | extent_count++; | |
426 | } | |
427 | prev_bit = bit; | |
0b246afa | 428 | offset += fs_info->sectorsize; |
a5ed9182 OS |
429 | bitnr++; |
430 | } | |
431 | if (prev_bit == 1) { | |
432 | key.objectid = extent_start; | |
433 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
434 | key.offset = end - extent_start; | |
435 | ||
436 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
437 | if (ret) | |
438 | goto out; | |
439 | btrfs_release_path(path); | |
440 | ||
441 | extent_count++; | |
442 | } | |
443 | ||
444 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
445 | btrfs_err(fs_info, |
446 | "incorrect extent count for %llu; counted %u, expected %u", | |
a5ed9182 OS |
447 | block_group->key.objectid, extent_count, |
448 | expected_extent_count); | |
449 | ASSERT(0); | |
450 | ret = -EIO; | |
451 | goto out; | |
452 | } | |
453 | ||
454 | ret = 0; | |
455 | out: | |
79b134a2 | 456 | kvfree(bitmap); |
a5ed9182 | 457 | if (ret) |
66642832 | 458 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
459 | return ret; |
460 | } | |
461 | ||
462 | static int update_free_space_extent_count(struct btrfs_trans_handle *trans, | |
463 | struct btrfs_fs_info *fs_info, | |
464 | struct btrfs_block_group_cache *block_group, | |
465 | struct btrfs_path *path, | |
466 | int new_extents) | |
467 | { | |
468 | struct btrfs_free_space_info *info; | |
469 | u32 flags; | |
470 | u32 extent_count; | |
471 | int ret = 0; | |
472 | ||
473 | if (new_extents == 0) | |
474 | return 0; | |
475 | ||
476 | info = search_free_space_info(trans, fs_info, block_group, path, 1); | |
477 | if (IS_ERR(info)) { | |
478 | ret = PTR_ERR(info); | |
479 | goto out; | |
480 | } | |
481 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
482 | extent_count = btrfs_free_space_extent_count(path->nodes[0], info); | |
483 | ||
484 | extent_count += new_extents; | |
485 | btrfs_set_free_space_extent_count(path->nodes[0], info, extent_count); | |
486 | btrfs_mark_buffer_dirty(path->nodes[0]); | |
487 | btrfs_release_path(path); | |
488 | ||
489 | if (!(flags & BTRFS_FREE_SPACE_USING_BITMAPS) && | |
490 | extent_count > block_group->bitmap_high_thresh) { | |
491 | ret = convert_free_space_to_bitmaps(trans, fs_info, block_group, | |
492 | path); | |
493 | } else if ((flags & BTRFS_FREE_SPACE_USING_BITMAPS) && | |
494 | extent_count < block_group->bitmap_low_thresh) { | |
495 | ret = convert_free_space_to_extents(trans, fs_info, block_group, | |
496 | path); | |
497 | } | |
498 | ||
499 | out: | |
500 | return ret; | |
501 | } | |
502 | ||
503 | int free_space_test_bit(struct btrfs_block_group_cache *block_group, | |
504 | struct btrfs_path *path, u64 offset) | |
505 | { | |
506 | struct extent_buffer *leaf; | |
507 | struct btrfs_key key; | |
508 | u64 found_start, found_end; | |
509 | unsigned long ptr, i; | |
510 | ||
511 | leaf = path->nodes[0]; | |
512 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
513 | ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); | |
514 | ||
515 | found_start = key.objectid; | |
516 | found_end = key.objectid + key.offset; | |
517 | ASSERT(offset >= found_start && offset < found_end); | |
518 | ||
519 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
da17066c JM |
520 | i = div_u64(offset - found_start, |
521 | block_group->fs_info->sectorsize); | |
a5ed9182 OS |
522 | return !!extent_buffer_test_bit(leaf, ptr, i); |
523 | } | |
524 | ||
525 | static void free_space_set_bits(struct btrfs_block_group_cache *block_group, | |
526 | struct btrfs_path *path, u64 *start, u64 *size, | |
527 | int bit) | |
528 | { | |
0b246afa | 529 | struct btrfs_fs_info *fs_info = block_group->fs_info; |
a5ed9182 OS |
530 | struct extent_buffer *leaf; |
531 | struct btrfs_key key; | |
532 | u64 end = *start + *size; | |
533 | u64 found_start, found_end; | |
534 | unsigned long ptr, first, last; | |
535 | ||
536 | leaf = path->nodes[0]; | |
537 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
538 | ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); | |
539 | ||
540 | found_start = key.objectid; | |
541 | found_end = key.objectid + key.offset; | |
542 | ASSERT(*start >= found_start && *start < found_end); | |
543 | ASSERT(end > found_start); | |
544 | ||
545 | if (end > found_end) | |
546 | end = found_end; | |
547 | ||
548 | ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); | |
0b246afa JM |
549 | first = div_u64(*start - found_start, fs_info->sectorsize); |
550 | last = div_u64(end - found_start, fs_info->sectorsize); | |
a5ed9182 OS |
551 | if (bit) |
552 | extent_buffer_bitmap_set(leaf, ptr, first, last - first); | |
553 | else | |
554 | extent_buffer_bitmap_clear(leaf, ptr, first, last - first); | |
555 | btrfs_mark_buffer_dirty(leaf); | |
556 | ||
557 | *size -= end - *start; | |
558 | *start = end; | |
559 | } | |
560 | ||
561 | /* | |
562 | * We can't use btrfs_next_item() in modify_free_space_bitmap() because | |
563 | * btrfs_next_leaf() doesn't get the path for writing. We can forgo the fancy | |
564 | * tree walking in btrfs_next_leaf() anyways because we know exactly what we're | |
565 | * looking for. | |
566 | */ | |
567 | static int free_space_next_bitmap(struct btrfs_trans_handle *trans, | |
568 | struct btrfs_root *root, struct btrfs_path *p) | |
569 | { | |
570 | struct btrfs_key key; | |
571 | ||
572 | if (p->slots[0] + 1 < btrfs_header_nritems(p->nodes[0])) { | |
573 | p->slots[0]++; | |
574 | return 0; | |
575 | } | |
576 | ||
577 | btrfs_item_key_to_cpu(p->nodes[0], &key, p->slots[0]); | |
578 | btrfs_release_path(p); | |
579 | ||
580 | key.objectid += key.offset; | |
581 | key.type = (u8)-1; | |
582 | key.offset = (u64)-1; | |
583 | ||
584 | return btrfs_search_prev_slot(trans, root, &key, p, 0, 1); | |
585 | } | |
586 | ||
587 | /* | |
588 | * If remove is 1, then we are removing free space, thus clearing bits in the | |
589 | * bitmap. If remove is 0, then we are adding free space, thus setting bits in | |
590 | * the bitmap. | |
591 | */ | |
592 | static int modify_free_space_bitmap(struct btrfs_trans_handle *trans, | |
593 | struct btrfs_fs_info *fs_info, | |
594 | struct btrfs_block_group_cache *block_group, | |
595 | struct btrfs_path *path, | |
596 | u64 start, u64 size, int remove) | |
597 | { | |
598 | struct btrfs_root *root = fs_info->free_space_root; | |
599 | struct btrfs_key key; | |
600 | u64 end = start + size; | |
601 | u64 cur_start, cur_size; | |
602 | int prev_bit, next_bit; | |
603 | int new_extents; | |
604 | int ret; | |
605 | ||
606 | /* | |
607 | * Read the bit for the block immediately before the extent of space if | |
608 | * that block is within the block group. | |
609 | */ | |
610 | if (start > block_group->key.objectid) { | |
da17066c | 611 | u64 prev_block = start - block_group->fs_info->sectorsize; |
a5ed9182 OS |
612 | |
613 | key.objectid = prev_block; | |
614 | key.type = (u8)-1; | |
615 | key.offset = (u64)-1; | |
616 | ||
617 | ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1); | |
618 | if (ret) | |
619 | goto out; | |
620 | ||
621 | prev_bit = free_space_test_bit(block_group, path, prev_block); | |
622 | ||
623 | /* The previous block may have been in the previous bitmap. */ | |
624 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
625 | if (start >= key.objectid + key.offset) { | |
626 | ret = free_space_next_bitmap(trans, root, path); | |
627 | if (ret) | |
628 | goto out; | |
629 | } | |
630 | } else { | |
631 | key.objectid = start; | |
632 | key.type = (u8)-1; | |
633 | key.offset = (u64)-1; | |
634 | ||
635 | ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1); | |
636 | if (ret) | |
637 | goto out; | |
638 | ||
639 | prev_bit = -1; | |
640 | } | |
641 | ||
642 | /* | |
643 | * Iterate over all of the bitmaps overlapped by the extent of space, | |
644 | * clearing/setting bits as required. | |
645 | */ | |
646 | cur_start = start; | |
647 | cur_size = size; | |
648 | while (1) { | |
649 | free_space_set_bits(block_group, path, &cur_start, &cur_size, | |
650 | !remove); | |
651 | if (cur_size == 0) | |
652 | break; | |
653 | ret = free_space_next_bitmap(trans, root, path); | |
654 | if (ret) | |
655 | goto out; | |
656 | } | |
657 | ||
658 | /* | |
659 | * Read the bit for the block immediately after the extent of space if | |
660 | * that block is within the block group. | |
661 | */ | |
662 | if (end < block_group->key.objectid + block_group->key.offset) { | |
663 | /* The next block may be in the next bitmap. */ | |
664 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
665 | if (end >= key.objectid + key.offset) { | |
666 | ret = free_space_next_bitmap(trans, root, path); | |
667 | if (ret) | |
668 | goto out; | |
669 | } | |
670 | ||
671 | next_bit = free_space_test_bit(block_group, path, end); | |
672 | } else { | |
673 | next_bit = -1; | |
674 | } | |
675 | ||
676 | if (remove) { | |
677 | new_extents = -1; | |
678 | if (prev_bit == 1) { | |
679 | /* Leftover on the left. */ | |
680 | new_extents++; | |
681 | } | |
682 | if (next_bit == 1) { | |
683 | /* Leftover on the right. */ | |
684 | new_extents++; | |
685 | } | |
686 | } else { | |
687 | new_extents = 1; | |
688 | if (prev_bit == 1) { | |
689 | /* Merging with neighbor on the left. */ | |
690 | new_extents--; | |
691 | } | |
692 | if (next_bit == 1) { | |
693 | /* Merging with neighbor on the right. */ | |
694 | new_extents--; | |
695 | } | |
696 | } | |
697 | ||
698 | btrfs_release_path(path); | |
699 | ret = update_free_space_extent_count(trans, fs_info, block_group, path, | |
700 | new_extents); | |
701 | ||
702 | out: | |
703 | return ret; | |
704 | } | |
705 | ||
706 | static int remove_free_space_extent(struct btrfs_trans_handle *trans, | |
707 | struct btrfs_fs_info *fs_info, | |
708 | struct btrfs_block_group_cache *block_group, | |
709 | struct btrfs_path *path, | |
710 | u64 start, u64 size) | |
711 | { | |
712 | struct btrfs_root *root = fs_info->free_space_root; | |
713 | struct btrfs_key key; | |
714 | u64 found_start, found_end; | |
715 | u64 end = start + size; | |
716 | int new_extents = -1; | |
717 | int ret; | |
718 | ||
719 | key.objectid = start; | |
720 | key.type = (u8)-1; | |
721 | key.offset = (u64)-1; | |
722 | ||
723 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
724 | if (ret) | |
725 | goto out; | |
726 | ||
727 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
728 | ||
729 | ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY); | |
730 | ||
731 | found_start = key.objectid; | |
732 | found_end = key.objectid + key.offset; | |
733 | ASSERT(start >= found_start && end <= found_end); | |
734 | ||
735 | /* | |
736 | * Okay, now that we've found the free space extent which contains the | |
737 | * free space that we are removing, there are four cases: | |
738 | * | |
739 | * 1. We're using the whole extent: delete the key we found and | |
740 | * decrement the free space extent count. | |
741 | * 2. We are using part of the extent starting at the beginning: delete | |
742 | * the key we found and insert a new key representing the leftover at | |
743 | * the end. There is no net change in the number of extents. | |
744 | * 3. We are using part of the extent ending at the end: delete the key | |
745 | * we found and insert a new key representing the leftover at the | |
746 | * beginning. There is no net change in the number of extents. | |
747 | * 4. We are using part of the extent in the middle: delete the key we | |
748 | * found and insert two new keys representing the leftovers on each | |
749 | * side. Where we used to have one extent, we now have two, so increment | |
750 | * the extent count. We may need to convert the block group to bitmaps | |
751 | * as a result. | |
752 | */ | |
753 | ||
754 | /* Delete the existing key (cases 1-4). */ | |
755 | ret = btrfs_del_item(trans, root, path); | |
756 | if (ret) | |
757 | goto out; | |
758 | ||
759 | /* Add a key for leftovers at the beginning (cases 3 and 4). */ | |
760 | if (start > found_start) { | |
761 | key.objectid = found_start; | |
762 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
763 | key.offset = start - found_start; | |
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 | /* Add a key for leftovers at the end (cases 2 and 4). */ | |
773 | if (end < found_end) { | |
774 | key.objectid = end; | |
775 | key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
776 | key.offset = found_end - end; | |
777 | ||
778 | btrfs_release_path(path); | |
779 | ret = btrfs_insert_empty_item(trans, root, path, &key, 0); | |
780 | if (ret) | |
781 | goto out; | |
782 | new_extents++; | |
783 | } | |
784 | ||
785 | btrfs_release_path(path); | |
786 | ret = update_free_space_extent_count(trans, fs_info, block_group, path, | |
787 | new_extents); | |
788 | ||
789 | out: | |
790 | return ret; | |
791 | } | |
792 | ||
793 | int __remove_from_free_space_tree(struct btrfs_trans_handle *trans, | |
794 | struct btrfs_fs_info *fs_info, | |
795 | struct btrfs_block_group_cache *block_group, | |
796 | struct btrfs_path *path, u64 start, u64 size) | |
797 | { | |
798 | struct btrfs_free_space_info *info; | |
799 | u32 flags; | |
800 | int ret; | |
801 | ||
802 | if (block_group->needs_free_space) { | |
803 | ret = __add_block_group_free_space(trans, fs_info, block_group, | |
804 | path); | |
805 | if (ret) | |
806 | return ret; | |
807 | } | |
808 | ||
809 | info = search_free_space_info(NULL, fs_info, block_group, path, 0); | |
810 | if (IS_ERR(info)) | |
811 | return PTR_ERR(info); | |
812 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
813 | btrfs_release_path(path); | |
814 | ||
815 | if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { | |
816 | return modify_free_space_bitmap(trans, fs_info, block_group, | |
817 | path, start, size, 1); | |
818 | } else { | |
819 | return remove_free_space_extent(trans, fs_info, block_group, | |
820 | path, start, size); | |
821 | } | |
822 | } | |
823 | ||
824 | int remove_from_free_space_tree(struct btrfs_trans_handle *trans, | |
825 | struct btrfs_fs_info *fs_info, | |
826 | u64 start, u64 size) | |
827 | { | |
828 | struct btrfs_block_group_cache *block_group; | |
829 | struct btrfs_path *path; | |
830 | int ret; | |
831 | ||
832 | if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) | |
833 | return 0; | |
834 | ||
835 | path = btrfs_alloc_path(); | |
836 | if (!path) { | |
837 | ret = -ENOMEM; | |
838 | goto out; | |
839 | } | |
840 | ||
841 | block_group = btrfs_lookup_block_group(fs_info, start); | |
842 | if (!block_group) { | |
843 | ASSERT(0); | |
844 | ret = -ENOENT; | |
845 | goto out; | |
846 | } | |
847 | ||
848 | mutex_lock(&block_group->free_space_lock); | |
849 | ret = __remove_from_free_space_tree(trans, fs_info, block_group, path, | |
850 | start, size); | |
851 | mutex_unlock(&block_group->free_space_lock); | |
852 | ||
853 | btrfs_put_block_group(block_group); | |
854 | out: | |
855 | btrfs_free_path(path); | |
856 | if (ret) | |
66642832 | 857 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
858 | return ret; |
859 | } | |
860 | ||
861 | static int add_free_space_extent(struct btrfs_trans_handle *trans, | |
862 | struct btrfs_fs_info *fs_info, | |
863 | struct btrfs_block_group_cache *block_group, | |
864 | struct btrfs_path *path, | |
865 | u64 start, u64 size) | |
866 | { | |
867 | struct btrfs_root *root = fs_info->free_space_root; | |
868 | struct btrfs_key key, new_key; | |
869 | u64 found_start, found_end; | |
870 | u64 end = start + size; | |
871 | int new_extents = 1; | |
872 | int ret; | |
873 | ||
874 | /* | |
875 | * We are adding a new extent of free space, but we need to merge | |
876 | * extents. There are four cases here: | |
877 | * | |
878 | * 1. The new extent does not have any immediate neighbors to merge | |
879 | * with: add the new key and increment the free space extent count. We | |
880 | * may need to convert the block group to bitmaps as a result. | |
881 | * 2. The new extent has an immediate neighbor before it: remove the | |
882 | * previous key and insert a new key combining both of them. There is no | |
883 | * net change in the number of extents. | |
884 | * 3. The new extent has an immediate neighbor after it: remove the next | |
885 | * key and insert a new key combining both of them. There is no net | |
886 | * change in the number of extents. | |
887 | * 4. The new extent has immediate neighbors on both sides: remove both | |
888 | * of the keys and insert a new key combining all of them. Where we used | |
889 | * to have two extents, we now have one, so decrement the extent count. | |
890 | */ | |
891 | ||
892 | new_key.objectid = start; | |
893 | new_key.type = BTRFS_FREE_SPACE_EXTENT_KEY; | |
894 | new_key.offset = size; | |
895 | ||
896 | /* Search for a neighbor on the left. */ | |
897 | if (start == block_group->key.objectid) | |
898 | goto right; | |
899 | key.objectid = start - 1; | |
900 | key.type = (u8)-1; | |
901 | key.offset = (u64)-1; | |
902 | ||
903 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
904 | if (ret) | |
905 | goto out; | |
906 | ||
907 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
908 | ||
909 | if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) { | |
910 | ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY); | |
911 | btrfs_release_path(path); | |
912 | goto right; | |
913 | } | |
914 | ||
915 | found_start = key.objectid; | |
916 | found_end = key.objectid + key.offset; | |
917 | ASSERT(found_start >= block_group->key.objectid && | |
918 | found_end > block_group->key.objectid); | |
919 | ASSERT(found_start < start && found_end <= start); | |
920 | ||
921 | /* | |
922 | * Delete the neighbor on the left and absorb it into the new key (cases | |
923 | * 2 and 4). | |
924 | */ | |
925 | if (found_end == start) { | |
926 | ret = btrfs_del_item(trans, root, path); | |
927 | if (ret) | |
928 | goto out; | |
929 | new_key.objectid = found_start; | |
930 | new_key.offset += key.offset; | |
931 | new_extents--; | |
932 | } | |
933 | btrfs_release_path(path); | |
934 | ||
935 | right: | |
936 | /* Search for a neighbor on the right. */ | |
937 | if (end == block_group->key.objectid + block_group->key.offset) | |
938 | goto insert; | |
939 | key.objectid = end; | |
940 | key.type = (u8)-1; | |
941 | key.offset = (u64)-1; | |
942 | ||
943 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
944 | if (ret) | |
945 | goto out; | |
946 | ||
947 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
948 | ||
949 | if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) { | |
950 | ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY); | |
951 | btrfs_release_path(path); | |
952 | goto insert; | |
953 | } | |
954 | ||
955 | found_start = key.objectid; | |
956 | found_end = key.objectid + key.offset; | |
957 | ASSERT(found_start >= block_group->key.objectid && | |
958 | found_end > block_group->key.objectid); | |
959 | ASSERT((found_start < start && found_end <= start) || | |
960 | (found_start >= end && found_end > end)); | |
961 | ||
962 | /* | |
963 | * Delete the neighbor on the right and absorb it into the new key | |
964 | * (cases 3 and 4). | |
965 | */ | |
966 | if (found_start == end) { | |
967 | ret = btrfs_del_item(trans, root, path); | |
968 | if (ret) | |
969 | goto out; | |
970 | new_key.offset += key.offset; | |
971 | new_extents--; | |
972 | } | |
973 | btrfs_release_path(path); | |
974 | ||
975 | insert: | |
976 | /* Insert the new key (cases 1-4). */ | |
977 | ret = btrfs_insert_empty_item(trans, root, path, &new_key, 0); | |
978 | if (ret) | |
979 | goto out; | |
980 | ||
981 | btrfs_release_path(path); | |
982 | ret = update_free_space_extent_count(trans, fs_info, block_group, path, | |
983 | new_extents); | |
984 | ||
985 | out: | |
986 | return ret; | |
987 | } | |
988 | ||
989 | int __add_to_free_space_tree(struct btrfs_trans_handle *trans, | |
990 | struct btrfs_fs_info *fs_info, | |
991 | struct btrfs_block_group_cache *block_group, | |
992 | struct btrfs_path *path, u64 start, u64 size) | |
993 | { | |
994 | struct btrfs_free_space_info *info; | |
995 | u32 flags; | |
996 | int ret; | |
997 | ||
998 | if (block_group->needs_free_space) { | |
999 | ret = __add_block_group_free_space(trans, fs_info, block_group, | |
1000 | path); | |
1001 | if (ret) | |
1002 | return ret; | |
1003 | } | |
1004 | ||
1005 | info = search_free_space_info(NULL, fs_info, block_group, path, 0); | |
1006 | if (IS_ERR(info)) | |
1007 | return PTR_ERR(info); | |
1008 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
1009 | btrfs_release_path(path); | |
1010 | ||
1011 | if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { | |
1012 | return modify_free_space_bitmap(trans, fs_info, block_group, | |
1013 | path, start, size, 0); | |
1014 | } else { | |
1015 | return add_free_space_extent(trans, fs_info, block_group, path, | |
1016 | start, size); | |
1017 | } | |
1018 | } | |
1019 | ||
1020 | int add_to_free_space_tree(struct btrfs_trans_handle *trans, | |
1021 | struct btrfs_fs_info *fs_info, | |
1022 | u64 start, u64 size) | |
1023 | { | |
1024 | struct btrfs_block_group_cache *block_group; | |
1025 | struct btrfs_path *path; | |
1026 | int ret; | |
1027 | ||
1028 | if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) | |
1029 | return 0; | |
1030 | ||
1031 | path = btrfs_alloc_path(); | |
1032 | if (!path) { | |
1033 | ret = -ENOMEM; | |
1034 | goto out; | |
1035 | } | |
1036 | ||
1037 | block_group = btrfs_lookup_block_group(fs_info, start); | |
1038 | if (!block_group) { | |
1039 | ASSERT(0); | |
1040 | ret = -ENOENT; | |
1041 | goto out; | |
1042 | } | |
1043 | ||
1044 | mutex_lock(&block_group->free_space_lock); | |
1045 | ret = __add_to_free_space_tree(trans, fs_info, block_group, path, start, | |
1046 | size); | |
1047 | mutex_unlock(&block_group->free_space_lock); | |
1048 | ||
1049 | btrfs_put_block_group(block_group); | |
1050 | out: | |
1051 | btrfs_free_path(path); | |
1052 | if (ret) | |
66642832 | 1053 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
1054 | return ret; |
1055 | } | |
1056 | ||
1057 | /* | |
1058 | * Populate the free space tree by walking the extent tree. Operations on the | |
1059 | * extent tree that happen as a result of writes to the free space tree will go | |
1060 | * through the normal add/remove hooks. | |
1061 | */ | |
1062 | static int populate_free_space_tree(struct btrfs_trans_handle *trans, | |
1063 | struct btrfs_fs_info *fs_info, | |
1064 | struct btrfs_block_group_cache *block_group) | |
1065 | { | |
1066 | struct btrfs_root *extent_root = fs_info->extent_root; | |
1067 | struct btrfs_path *path, *path2; | |
1068 | struct btrfs_key key; | |
1069 | u64 start, end; | |
1070 | int ret; | |
1071 | ||
1072 | path = btrfs_alloc_path(); | |
1073 | if (!path) | |
1074 | return -ENOMEM; | |
1075 | path->reada = 1; | |
1076 | ||
1077 | path2 = btrfs_alloc_path(); | |
1078 | if (!path2) { | |
1079 | btrfs_free_path(path); | |
1080 | return -ENOMEM; | |
1081 | } | |
1082 | ||
1083 | ret = add_new_free_space_info(trans, fs_info, block_group, path2); | |
1084 | if (ret) | |
1085 | goto out; | |
1086 | ||
511711af CM |
1087 | mutex_lock(&block_group->free_space_lock); |
1088 | ||
a5ed9182 OS |
1089 | /* |
1090 | * Iterate through all of the extent and metadata items in this block | |
1091 | * group, adding the free space between them and the free space at the | |
1092 | * end. Note that EXTENT_ITEM and METADATA_ITEM are less than | |
1093 | * BLOCK_GROUP_ITEM, so an extent may precede the block group that it's | |
1094 | * contained in. | |
1095 | */ | |
1096 | key.objectid = block_group->key.objectid; | |
1097 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
1098 | key.offset = 0; | |
1099 | ||
1100 | ret = btrfs_search_slot_for_read(extent_root, &key, path, 1, 0); | |
1101 | if (ret < 0) | |
511711af | 1102 | goto out_locked; |
a5ed9182 OS |
1103 | ASSERT(ret == 0); |
1104 | ||
1105 | start = block_group->key.objectid; | |
1106 | end = block_group->key.objectid + block_group->key.offset; | |
1107 | while (1) { | |
1108 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1109 | ||
1110 | if (key.type == BTRFS_EXTENT_ITEM_KEY || | |
1111 | key.type == BTRFS_METADATA_ITEM_KEY) { | |
1112 | if (key.objectid >= end) | |
1113 | break; | |
1114 | ||
1115 | if (start < key.objectid) { | |
1116 | ret = __add_to_free_space_tree(trans, fs_info, | |
1117 | block_group, | |
1118 | path2, start, | |
1119 | key.objectid - | |
1120 | start); | |
1121 | if (ret) | |
511711af | 1122 | goto out_locked; |
a5ed9182 OS |
1123 | } |
1124 | start = key.objectid; | |
1125 | if (key.type == BTRFS_METADATA_ITEM_KEY) | |
da17066c | 1126 | start += fs_info->nodesize; |
a5ed9182 OS |
1127 | else |
1128 | start += key.offset; | |
1129 | } else if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) { | |
1130 | if (key.objectid != block_group->key.objectid) | |
1131 | break; | |
1132 | } | |
1133 | ||
1134 | ret = btrfs_next_item(extent_root, path); | |
1135 | if (ret < 0) | |
511711af | 1136 | goto out_locked; |
a5ed9182 OS |
1137 | if (ret) |
1138 | break; | |
1139 | } | |
1140 | if (start < end) { | |
1141 | ret = __add_to_free_space_tree(trans, fs_info, block_group, | |
1142 | path2, start, end - start); | |
1143 | if (ret) | |
511711af | 1144 | goto out_locked; |
a5ed9182 OS |
1145 | } |
1146 | ||
1147 | ret = 0; | |
511711af CM |
1148 | out_locked: |
1149 | mutex_unlock(&block_group->free_space_lock); | |
a5ed9182 OS |
1150 | out: |
1151 | btrfs_free_path(path2); | |
1152 | btrfs_free_path(path); | |
1153 | return ret; | |
1154 | } | |
1155 | ||
1156 | int btrfs_create_free_space_tree(struct btrfs_fs_info *fs_info) | |
1157 | { | |
1158 | struct btrfs_trans_handle *trans; | |
1159 | struct btrfs_root *tree_root = fs_info->tree_root; | |
1160 | struct btrfs_root *free_space_root; | |
1161 | struct btrfs_block_group_cache *block_group; | |
1162 | struct rb_node *node; | |
1163 | int ret; | |
1164 | ||
1165 | trans = btrfs_start_transaction(tree_root, 0); | |
1166 | if (IS_ERR(trans)) | |
1167 | return PTR_ERR(trans); | |
1168 | ||
afcdd129 | 1169 | set_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); |
a5ed9182 OS |
1170 | free_space_root = btrfs_create_tree(trans, fs_info, |
1171 | BTRFS_FREE_SPACE_TREE_OBJECTID); | |
1172 | if (IS_ERR(free_space_root)) { | |
1173 | ret = PTR_ERR(free_space_root); | |
1174 | goto abort; | |
1175 | } | |
1176 | fs_info->free_space_root = free_space_root; | |
1177 | ||
1178 | node = rb_first(&fs_info->block_group_cache_tree); | |
1179 | while (node) { | |
1180 | block_group = rb_entry(node, struct btrfs_block_group_cache, | |
1181 | cache_node); | |
1182 | ret = populate_free_space_tree(trans, fs_info, block_group); | |
1183 | if (ret) | |
1184 | goto abort; | |
1185 | node = rb_next(node); | |
1186 | } | |
1187 | ||
1188 | btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE); | |
6675df31 | 1189 | btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); |
afcdd129 | 1190 | clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); |
a5ed9182 | 1191 | |
3a45bb20 | 1192 | ret = btrfs_commit_transaction(trans); |
a5ed9182 OS |
1193 | if (ret) |
1194 | return ret; | |
1195 | ||
1196 | return 0; | |
1197 | ||
1198 | abort: | |
afcdd129 | 1199 | clear_bit(BTRFS_FS_CREATING_FREE_SPACE_TREE, &fs_info->flags); |
66642832 | 1200 | btrfs_abort_transaction(trans, ret); |
3a45bb20 | 1201 | btrfs_end_transaction(trans); |
a5ed9182 OS |
1202 | return ret; |
1203 | } | |
1204 | ||
1205 | static int clear_free_space_tree(struct btrfs_trans_handle *trans, | |
1206 | struct btrfs_root *root) | |
1207 | { | |
1208 | struct btrfs_path *path; | |
1209 | struct btrfs_key key; | |
1210 | int nr; | |
1211 | int ret; | |
1212 | ||
1213 | path = btrfs_alloc_path(); | |
1214 | if (!path) | |
1215 | return -ENOMEM; | |
1216 | ||
1217 | path->leave_spinning = 1; | |
1218 | ||
1219 | key.objectid = 0; | |
1220 | key.type = 0; | |
1221 | key.offset = 0; | |
1222 | ||
1223 | while (1) { | |
1224 | ret = btrfs_search_slot(trans, root, &key, path, -1, 1); | |
1225 | if (ret < 0) | |
1226 | goto out; | |
1227 | ||
1228 | nr = btrfs_header_nritems(path->nodes[0]); | |
1229 | if (!nr) | |
1230 | break; | |
1231 | ||
1232 | path->slots[0] = 0; | |
1233 | ret = btrfs_del_items(trans, root, path, 0, nr); | |
1234 | if (ret) | |
1235 | goto out; | |
1236 | ||
1237 | btrfs_release_path(path); | |
1238 | } | |
1239 | ||
1240 | ret = 0; | |
1241 | out: | |
1242 | btrfs_free_path(path); | |
1243 | return ret; | |
1244 | } | |
1245 | ||
1246 | int btrfs_clear_free_space_tree(struct btrfs_fs_info *fs_info) | |
1247 | { | |
1248 | struct btrfs_trans_handle *trans; | |
1249 | struct btrfs_root *tree_root = fs_info->tree_root; | |
1250 | struct btrfs_root *free_space_root = fs_info->free_space_root; | |
1251 | int ret; | |
1252 | ||
1253 | trans = btrfs_start_transaction(tree_root, 0); | |
1254 | if (IS_ERR(trans)) | |
1255 | return PTR_ERR(trans); | |
1256 | ||
1257 | btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE); | |
6675df31 | 1258 | btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE_VALID); |
a5ed9182 OS |
1259 | fs_info->free_space_root = NULL; |
1260 | ||
1261 | ret = clear_free_space_tree(trans, free_space_root); | |
1262 | if (ret) | |
1263 | goto abort; | |
1264 | ||
1265 | ret = btrfs_del_root(trans, tree_root, &free_space_root->root_key); | |
1266 | if (ret) | |
1267 | goto abort; | |
1268 | ||
1269 | list_del(&free_space_root->dirty_list); | |
1270 | ||
1271 | btrfs_tree_lock(free_space_root->node); | |
0b246afa | 1272 | clean_tree_block(trans, fs_info, free_space_root->node); |
a5ed9182 OS |
1273 | btrfs_tree_unlock(free_space_root->node); |
1274 | btrfs_free_tree_block(trans, free_space_root, free_space_root->node, | |
1275 | 0, 1); | |
1276 | ||
1277 | free_extent_buffer(free_space_root->node); | |
1278 | free_extent_buffer(free_space_root->commit_root); | |
1279 | kfree(free_space_root); | |
1280 | ||
3a45bb20 | 1281 | ret = btrfs_commit_transaction(trans); |
a5ed9182 OS |
1282 | if (ret) |
1283 | return ret; | |
1284 | ||
1285 | return 0; | |
1286 | ||
1287 | abort: | |
66642832 | 1288 | btrfs_abort_transaction(trans, ret); |
3a45bb20 | 1289 | btrfs_end_transaction(trans); |
a5ed9182 OS |
1290 | return ret; |
1291 | } | |
1292 | ||
1293 | static int __add_block_group_free_space(struct btrfs_trans_handle *trans, | |
1294 | struct btrfs_fs_info *fs_info, | |
1295 | struct btrfs_block_group_cache *block_group, | |
1296 | struct btrfs_path *path) | |
1297 | { | |
1298 | u64 start, end; | |
1299 | int ret; | |
1300 | ||
1301 | start = block_group->key.objectid; | |
1302 | end = block_group->key.objectid + block_group->key.offset; | |
1303 | ||
1304 | block_group->needs_free_space = 0; | |
1305 | ||
1306 | ret = add_new_free_space_info(trans, fs_info, block_group, path); | |
1307 | if (ret) | |
1308 | return ret; | |
1309 | ||
1310 | return __add_to_free_space_tree(trans, fs_info, block_group, path, | |
1311 | block_group->key.objectid, | |
1312 | block_group->key.offset); | |
1313 | } | |
1314 | ||
1315 | int add_block_group_free_space(struct btrfs_trans_handle *trans, | |
1316 | struct btrfs_fs_info *fs_info, | |
1317 | struct btrfs_block_group_cache *block_group) | |
1318 | { | |
1319 | struct btrfs_path *path = NULL; | |
1320 | int ret = 0; | |
1321 | ||
1322 | if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) | |
1323 | return 0; | |
1324 | ||
1325 | mutex_lock(&block_group->free_space_lock); | |
1326 | if (!block_group->needs_free_space) | |
1327 | goto out; | |
1328 | ||
1329 | path = btrfs_alloc_path(); | |
1330 | if (!path) { | |
1331 | ret = -ENOMEM; | |
1332 | goto out; | |
1333 | } | |
1334 | ||
1335 | ret = __add_block_group_free_space(trans, fs_info, block_group, path); | |
1336 | ||
1337 | out: | |
1338 | btrfs_free_path(path); | |
1339 | mutex_unlock(&block_group->free_space_lock); | |
1340 | if (ret) | |
66642832 | 1341 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
1342 | return ret; |
1343 | } | |
1344 | ||
1345 | int remove_block_group_free_space(struct btrfs_trans_handle *trans, | |
1346 | struct btrfs_fs_info *fs_info, | |
1347 | struct btrfs_block_group_cache *block_group) | |
1348 | { | |
1349 | struct btrfs_root *root = fs_info->free_space_root; | |
1350 | struct btrfs_path *path; | |
1351 | struct btrfs_key key, found_key; | |
1352 | struct extent_buffer *leaf; | |
1353 | u64 start, end; | |
1354 | int done = 0, nr; | |
1355 | int ret; | |
1356 | ||
1357 | if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) | |
1358 | return 0; | |
1359 | ||
1360 | if (block_group->needs_free_space) { | |
1361 | /* We never added this block group to the free space tree. */ | |
1362 | return 0; | |
1363 | } | |
1364 | ||
1365 | path = btrfs_alloc_path(); | |
1366 | if (!path) { | |
1367 | ret = -ENOMEM; | |
1368 | goto out; | |
1369 | } | |
1370 | ||
1371 | start = block_group->key.objectid; | |
1372 | end = block_group->key.objectid + block_group->key.offset; | |
1373 | ||
1374 | key.objectid = end - 1; | |
1375 | key.type = (u8)-1; | |
1376 | key.offset = (u64)-1; | |
1377 | ||
1378 | while (!done) { | |
1379 | ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); | |
1380 | if (ret) | |
1381 | goto out; | |
1382 | ||
1383 | leaf = path->nodes[0]; | |
1384 | nr = 0; | |
1385 | path->slots[0]++; | |
1386 | while (path->slots[0] > 0) { | |
1387 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); | |
1388 | ||
1389 | if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { | |
1390 | ASSERT(found_key.objectid == block_group->key.objectid); | |
1391 | ASSERT(found_key.offset == block_group->key.offset); | |
1392 | done = 1; | |
1393 | nr++; | |
1394 | path->slots[0]--; | |
1395 | break; | |
1396 | } else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY || | |
1397 | found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) { | |
1398 | ASSERT(found_key.objectid >= start); | |
1399 | ASSERT(found_key.objectid < end); | |
1400 | ASSERT(found_key.objectid + found_key.offset <= end); | |
1401 | nr++; | |
1402 | path->slots[0]--; | |
1403 | } else { | |
1404 | ASSERT(0); | |
1405 | } | |
1406 | } | |
1407 | ||
1408 | ret = btrfs_del_items(trans, root, path, path->slots[0], nr); | |
1409 | if (ret) | |
1410 | goto out; | |
1411 | btrfs_release_path(path); | |
1412 | } | |
1413 | ||
1414 | ret = 0; | |
1415 | out: | |
1416 | btrfs_free_path(path); | |
1417 | if (ret) | |
66642832 | 1418 | btrfs_abort_transaction(trans, ret); |
a5ed9182 OS |
1419 | return ret; |
1420 | } | |
1421 | ||
1422 | static int load_free_space_bitmaps(struct btrfs_caching_control *caching_ctl, | |
1423 | struct btrfs_path *path, | |
1424 | u32 expected_extent_count) | |
1425 | { | |
1426 | struct btrfs_block_group_cache *block_group; | |
1427 | struct btrfs_fs_info *fs_info; | |
1428 | struct btrfs_root *root; | |
1429 | struct btrfs_key key; | |
1430 | int prev_bit = 0, bit; | |
1431 | /* Initialize to silence GCC. */ | |
1432 | u64 extent_start = 0; | |
1433 | u64 end, offset; | |
1434 | u64 total_found = 0; | |
1435 | u32 extent_count = 0; | |
1436 | int ret; | |
1437 | ||
1438 | block_group = caching_ctl->block_group; | |
1439 | fs_info = block_group->fs_info; | |
1440 | root = fs_info->free_space_root; | |
1441 | ||
1442 | end = block_group->key.objectid + block_group->key.offset; | |
1443 | ||
1444 | while (1) { | |
1445 | ret = btrfs_next_item(root, path); | |
1446 | if (ret < 0) | |
1447 | goto out; | |
1448 | if (ret) | |
1449 | break; | |
1450 | ||
1451 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1452 | ||
1453 | if (key.type == BTRFS_FREE_SPACE_INFO_KEY) | |
1454 | break; | |
1455 | ||
1456 | ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); | |
1457 | ASSERT(key.objectid < end && key.objectid + key.offset <= end); | |
1458 | ||
1459 | caching_ctl->progress = key.objectid; | |
1460 | ||
1461 | offset = key.objectid; | |
1462 | while (offset < key.objectid + key.offset) { | |
1463 | bit = free_space_test_bit(block_group, path, offset); | |
1464 | if (prev_bit == 0 && bit == 1) { | |
1465 | extent_start = offset; | |
1466 | } else if (prev_bit == 1 && bit == 0) { | |
1467 | total_found += add_new_free_space(block_group, | |
1468 | fs_info, | |
1469 | extent_start, | |
1470 | offset); | |
1471 | if (total_found > CACHING_CTL_WAKE_UP) { | |
1472 | total_found = 0; | |
1473 | wake_up(&caching_ctl->wait); | |
1474 | } | |
1475 | extent_count++; | |
1476 | } | |
1477 | prev_bit = bit; | |
0b246afa | 1478 | offset += fs_info->sectorsize; |
a5ed9182 OS |
1479 | } |
1480 | } | |
1481 | if (prev_bit == 1) { | |
1482 | total_found += add_new_free_space(block_group, fs_info, | |
1483 | extent_start, end); | |
1484 | extent_count++; | |
1485 | } | |
1486 | ||
1487 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
1488 | btrfs_err(fs_info, |
1489 | "incorrect extent count for %llu; counted %u, expected %u", | |
a5ed9182 OS |
1490 | block_group->key.objectid, extent_count, |
1491 | expected_extent_count); | |
1492 | ASSERT(0); | |
1493 | ret = -EIO; | |
1494 | goto out; | |
1495 | } | |
1496 | ||
1497 | caching_ctl->progress = (u64)-1; | |
1498 | ||
1499 | ret = 0; | |
1500 | out: | |
1501 | return ret; | |
1502 | } | |
1503 | ||
1504 | static int load_free_space_extents(struct btrfs_caching_control *caching_ctl, | |
1505 | struct btrfs_path *path, | |
1506 | u32 expected_extent_count) | |
1507 | { | |
1508 | struct btrfs_block_group_cache *block_group; | |
1509 | struct btrfs_fs_info *fs_info; | |
1510 | struct btrfs_root *root; | |
1511 | struct btrfs_key key; | |
1512 | u64 end; | |
1513 | u64 total_found = 0; | |
1514 | u32 extent_count = 0; | |
1515 | int ret; | |
1516 | ||
1517 | block_group = caching_ctl->block_group; | |
1518 | fs_info = block_group->fs_info; | |
1519 | root = fs_info->free_space_root; | |
1520 | ||
1521 | end = block_group->key.objectid + block_group->key.offset; | |
1522 | ||
1523 | while (1) { | |
1524 | ret = btrfs_next_item(root, path); | |
1525 | if (ret < 0) | |
1526 | goto out; | |
1527 | if (ret) | |
1528 | break; | |
1529 | ||
1530 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
1531 | ||
1532 | if (key.type == BTRFS_FREE_SPACE_INFO_KEY) | |
1533 | break; | |
1534 | ||
1535 | ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY); | |
1536 | ASSERT(key.objectid < end && key.objectid + key.offset <= end); | |
1537 | ||
1538 | caching_ctl->progress = key.objectid; | |
1539 | ||
1540 | total_found += add_new_free_space(block_group, fs_info, | |
1541 | key.objectid, | |
1542 | key.objectid + key.offset); | |
1543 | if (total_found > CACHING_CTL_WAKE_UP) { | |
1544 | total_found = 0; | |
1545 | wake_up(&caching_ctl->wait); | |
1546 | } | |
1547 | extent_count++; | |
1548 | } | |
1549 | ||
1550 | if (extent_count != expected_extent_count) { | |
5d163e0e JM |
1551 | btrfs_err(fs_info, |
1552 | "incorrect extent count for %llu; counted %u, expected %u", | |
a5ed9182 OS |
1553 | block_group->key.objectid, extent_count, |
1554 | expected_extent_count); | |
1555 | ASSERT(0); | |
1556 | ret = -EIO; | |
1557 | goto out; | |
1558 | } | |
1559 | ||
1560 | caching_ctl->progress = (u64)-1; | |
1561 | ||
1562 | ret = 0; | |
1563 | out: | |
1564 | return ret; | |
1565 | } | |
1566 | ||
1567 | int load_free_space_tree(struct btrfs_caching_control *caching_ctl) | |
1568 | { | |
1569 | struct btrfs_block_group_cache *block_group; | |
1570 | struct btrfs_fs_info *fs_info; | |
1571 | struct btrfs_free_space_info *info; | |
1572 | struct btrfs_path *path; | |
1573 | u32 extent_count, flags; | |
1574 | int ret; | |
1575 | ||
1576 | block_group = caching_ctl->block_group; | |
1577 | fs_info = block_group->fs_info; | |
1578 | ||
1579 | path = btrfs_alloc_path(); | |
1580 | if (!path) | |
1581 | return -ENOMEM; | |
1582 | ||
1583 | /* | |
1584 | * Just like caching_thread() doesn't want to deadlock on the extent | |
1585 | * tree, we don't want to deadlock on the free space tree. | |
1586 | */ | |
1587 | path->skip_locking = 1; | |
1588 | path->search_commit_root = 1; | |
1589 | path->reada = 1; | |
1590 | ||
1591 | info = search_free_space_info(NULL, fs_info, block_group, path, 0); | |
1592 | if (IS_ERR(info)) { | |
1593 | ret = PTR_ERR(info); | |
1594 | goto out; | |
1595 | } | |
1596 | extent_count = btrfs_free_space_extent_count(path->nodes[0], info); | |
1597 | flags = btrfs_free_space_flags(path->nodes[0], info); | |
1598 | ||
1599 | /* | |
1600 | * We left path pointing to the free space info item, so now | |
1601 | * load_free_space_foo can just iterate through the free space tree from | |
1602 | * there. | |
1603 | */ | |
1604 | if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) | |
1605 | ret = load_free_space_bitmaps(caching_ctl, path, extent_count); | |
1606 | else | |
1607 | ret = load_free_space_extents(caching_ctl, path, extent_count); | |
1608 | ||
1609 | out: | |
1610 | btrfs_free_path(path); | |
1611 | return ret; | |
1612 | } |