Commit | Line | Data |
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0f9dd46c JB |
1 | /* |
2 | * Copyright (C) 2008 Red Hat. 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 | ||
96303081 | 19 | #include <linux/pagemap.h> |
0f9dd46c | 20 | #include <linux/sched.h> |
5a0e3ad6 | 21 | #include <linux/slab.h> |
96303081 | 22 | #include <linux/math64.h> |
0f9dd46c | 23 | #include "ctree.h" |
fa9c0d79 CM |
24 | #include "free-space-cache.h" |
25 | #include "transaction.h" | |
0af3d00b | 26 | #include "disk-io.h" |
fa9c0d79 | 27 | |
96303081 JB |
28 | #define BITS_PER_BITMAP (PAGE_CACHE_SIZE * 8) |
29 | #define MAX_CACHE_BYTES_PER_GIG (32 * 1024) | |
0f9dd46c | 30 | |
0cb59c99 JB |
31 | static void recalculate_thresholds(struct btrfs_block_group_cache |
32 | *block_group); | |
33 | static int link_free_space(struct btrfs_block_group_cache *block_group, | |
34 | struct btrfs_free_space *info); | |
35 | ||
0af3d00b JB |
36 | struct inode *lookup_free_space_inode(struct btrfs_root *root, |
37 | struct btrfs_block_group_cache | |
38 | *block_group, struct btrfs_path *path) | |
39 | { | |
40 | struct btrfs_key key; | |
41 | struct btrfs_key location; | |
42 | struct btrfs_disk_key disk_key; | |
43 | struct btrfs_free_space_header *header; | |
44 | struct extent_buffer *leaf; | |
45 | struct inode *inode = NULL; | |
46 | int ret; | |
47 | ||
48 | spin_lock(&block_group->lock); | |
49 | if (block_group->inode) | |
50 | inode = igrab(block_group->inode); | |
51 | spin_unlock(&block_group->lock); | |
52 | if (inode) | |
53 | return inode; | |
54 | ||
55 | key.objectid = BTRFS_FREE_SPACE_OBJECTID; | |
56 | key.offset = block_group->key.objectid; | |
57 | key.type = 0; | |
58 | ||
59 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
60 | if (ret < 0) | |
61 | return ERR_PTR(ret); | |
62 | if (ret > 0) { | |
63 | btrfs_release_path(root, path); | |
64 | return ERR_PTR(-ENOENT); | |
65 | } | |
66 | ||
67 | leaf = path->nodes[0]; | |
68 | header = btrfs_item_ptr(leaf, path->slots[0], | |
69 | struct btrfs_free_space_header); | |
70 | btrfs_free_space_key(leaf, header, &disk_key); | |
71 | btrfs_disk_key_to_cpu(&location, &disk_key); | |
72 | btrfs_release_path(root, path); | |
73 | ||
74 | inode = btrfs_iget(root->fs_info->sb, &location, root, NULL); | |
75 | if (!inode) | |
76 | return ERR_PTR(-ENOENT); | |
77 | if (IS_ERR(inode)) | |
78 | return inode; | |
79 | if (is_bad_inode(inode)) { | |
80 | iput(inode); | |
81 | return ERR_PTR(-ENOENT); | |
82 | } | |
83 | ||
84 | spin_lock(&block_group->lock); | |
85 | if (!root->fs_info->closing) { | |
86 | block_group->inode = igrab(inode); | |
87 | block_group->iref = 1; | |
88 | } | |
89 | spin_unlock(&block_group->lock); | |
90 | ||
91 | return inode; | |
92 | } | |
93 | ||
94 | int create_free_space_inode(struct btrfs_root *root, | |
95 | struct btrfs_trans_handle *trans, | |
96 | struct btrfs_block_group_cache *block_group, | |
97 | struct btrfs_path *path) | |
98 | { | |
99 | struct btrfs_key key; | |
100 | struct btrfs_disk_key disk_key; | |
101 | struct btrfs_free_space_header *header; | |
102 | struct btrfs_inode_item *inode_item; | |
103 | struct extent_buffer *leaf; | |
104 | u64 objectid; | |
105 | int ret; | |
106 | ||
107 | ret = btrfs_find_free_objectid(trans, root, 0, &objectid); | |
108 | if (ret < 0) | |
109 | return ret; | |
110 | ||
111 | ret = btrfs_insert_empty_inode(trans, root, path, objectid); | |
112 | if (ret) | |
113 | return ret; | |
114 | ||
115 | leaf = path->nodes[0]; | |
116 | inode_item = btrfs_item_ptr(leaf, path->slots[0], | |
117 | struct btrfs_inode_item); | |
118 | btrfs_item_key(leaf, &disk_key, path->slots[0]); | |
119 | memset_extent_buffer(leaf, 0, (unsigned long)inode_item, | |
120 | sizeof(*inode_item)); | |
121 | btrfs_set_inode_generation(leaf, inode_item, trans->transid); | |
122 | btrfs_set_inode_size(leaf, inode_item, 0); | |
123 | btrfs_set_inode_nbytes(leaf, inode_item, 0); | |
124 | btrfs_set_inode_uid(leaf, inode_item, 0); | |
125 | btrfs_set_inode_gid(leaf, inode_item, 0); | |
126 | btrfs_set_inode_mode(leaf, inode_item, S_IFREG | 0600); | |
127 | btrfs_set_inode_flags(leaf, inode_item, BTRFS_INODE_NOCOMPRESS | | |
128 | BTRFS_INODE_PREALLOC | BTRFS_INODE_NODATASUM); | |
129 | btrfs_set_inode_nlink(leaf, inode_item, 1); | |
130 | btrfs_set_inode_transid(leaf, inode_item, trans->transid); | |
131 | btrfs_set_inode_block_group(leaf, inode_item, | |
132 | block_group->key.objectid); | |
133 | btrfs_mark_buffer_dirty(leaf); | |
134 | btrfs_release_path(root, path); | |
135 | ||
136 | key.objectid = BTRFS_FREE_SPACE_OBJECTID; | |
137 | key.offset = block_group->key.objectid; | |
138 | key.type = 0; | |
139 | ||
140 | ret = btrfs_insert_empty_item(trans, root, path, &key, | |
141 | sizeof(struct btrfs_free_space_header)); | |
142 | if (ret < 0) { | |
143 | btrfs_release_path(root, path); | |
144 | return ret; | |
145 | } | |
146 | leaf = path->nodes[0]; | |
147 | header = btrfs_item_ptr(leaf, path->slots[0], | |
148 | struct btrfs_free_space_header); | |
149 | memset_extent_buffer(leaf, 0, (unsigned long)header, sizeof(*header)); | |
150 | btrfs_set_free_space_key(leaf, header, &disk_key); | |
151 | btrfs_mark_buffer_dirty(leaf); | |
152 | btrfs_release_path(root, path); | |
153 | ||
154 | return 0; | |
155 | } | |
156 | ||
157 | int btrfs_truncate_free_space_cache(struct btrfs_root *root, | |
158 | struct btrfs_trans_handle *trans, | |
159 | struct btrfs_path *path, | |
160 | struct inode *inode) | |
161 | { | |
162 | loff_t oldsize; | |
163 | int ret = 0; | |
164 | ||
165 | trans->block_rsv = root->orphan_block_rsv; | |
166 | ret = btrfs_block_rsv_check(trans, root, | |
167 | root->orphan_block_rsv, | |
168 | 0, 5); | |
169 | if (ret) | |
170 | return ret; | |
171 | ||
172 | oldsize = i_size_read(inode); | |
173 | btrfs_i_size_write(inode, 0); | |
174 | truncate_pagecache(inode, oldsize, 0); | |
175 | ||
176 | /* | |
177 | * We don't need an orphan item because truncating the free space cache | |
178 | * will never be split across transactions. | |
179 | */ | |
180 | ret = btrfs_truncate_inode_items(trans, root, inode, | |
181 | 0, BTRFS_EXTENT_DATA_KEY); | |
182 | if (ret) { | |
183 | WARN_ON(1); | |
184 | return ret; | |
185 | } | |
186 | ||
187 | return btrfs_update_inode(trans, root, inode); | |
188 | } | |
189 | ||
9d66e233 JB |
190 | static int readahead_cache(struct inode *inode) |
191 | { | |
192 | struct file_ra_state *ra; | |
193 | unsigned long last_index; | |
194 | ||
195 | ra = kzalloc(sizeof(*ra), GFP_NOFS); | |
196 | if (!ra) | |
197 | return -ENOMEM; | |
198 | ||
199 | file_ra_state_init(ra, inode->i_mapping); | |
200 | last_index = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT; | |
201 | ||
202 | page_cache_sync_readahead(inode->i_mapping, ra, NULL, 0, last_index); | |
203 | ||
204 | kfree(ra); | |
205 | ||
206 | return 0; | |
207 | } | |
208 | ||
209 | int load_free_space_cache(struct btrfs_fs_info *fs_info, | |
210 | struct btrfs_block_group_cache *block_group) | |
211 | { | |
212 | struct btrfs_root *root = fs_info->tree_root; | |
213 | struct inode *inode; | |
214 | struct btrfs_free_space_header *header; | |
215 | struct extent_buffer *leaf; | |
216 | struct page *page; | |
217 | struct btrfs_path *path; | |
218 | u32 *checksums = NULL, *crc; | |
219 | char *disk_crcs = NULL; | |
220 | struct btrfs_key key; | |
221 | struct list_head bitmaps; | |
222 | u64 num_entries; | |
223 | u64 num_bitmaps; | |
224 | u64 generation; | |
225 | u32 cur_crc = ~(u32)0; | |
226 | pgoff_t index = 0; | |
227 | unsigned long first_page_offset; | |
228 | int num_checksums; | |
229 | int ret = 0; | |
230 | ||
231 | /* | |
232 | * If we're unmounting then just return, since this does a search on the | |
233 | * normal root and not the commit root and we could deadlock. | |
234 | */ | |
235 | smp_mb(); | |
236 | if (fs_info->closing) | |
237 | return 0; | |
238 | ||
239 | /* | |
240 | * If this block group has been marked to be cleared for one reason or | |
241 | * another then we can't trust the on disk cache, so just return. | |
242 | */ | |
243 | spin_lock(&block_group->lock); | |
244 | if (block_group->disk_cache_state != BTRFS_DC_WRITTEN) { | |
9d66e233 JB |
245 | spin_unlock(&block_group->lock); |
246 | return 0; | |
247 | } | |
248 | spin_unlock(&block_group->lock); | |
249 | ||
250 | INIT_LIST_HEAD(&bitmaps); | |
251 | ||
252 | path = btrfs_alloc_path(); | |
253 | if (!path) | |
254 | return 0; | |
255 | ||
256 | inode = lookup_free_space_inode(root, block_group, path); | |
257 | if (IS_ERR(inode)) { | |
258 | btrfs_free_path(path); | |
259 | return 0; | |
260 | } | |
261 | ||
262 | /* Nothing in the space cache, goodbye */ | |
263 | if (!i_size_read(inode)) { | |
264 | btrfs_free_path(path); | |
265 | goto out; | |
266 | } | |
267 | ||
268 | key.objectid = BTRFS_FREE_SPACE_OBJECTID; | |
269 | key.offset = block_group->key.objectid; | |
270 | key.type = 0; | |
271 | ||
272 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
273 | if (ret) { | |
274 | btrfs_free_path(path); | |
275 | goto out; | |
276 | } | |
277 | ||
278 | leaf = path->nodes[0]; | |
279 | header = btrfs_item_ptr(leaf, path->slots[0], | |
280 | struct btrfs_free_space_header); | |
281 | num_entries = btrfs_free_space_entries(leaf, header); | |
282 | num_bitmaps = btrfs_free_space_bitmaps(leaf, header); | |
283 | generation = btrfs_free_space_generation(leaf, header); | |
284 | btrfs_free_path(path); | |
285 | ||
286 | if (BTRFS_I(inode)->generation != generation) { | |
287 | printk(KERN_ERR "btrfs: free space inode generation (%llu) did" | |
288 | " not match free space cache generation (%llu) for " | |
289 | "block group %llu\n", | |
290 | (unsigned long long)BTRFS_I(inode)->generation, | |
291 | (unsigned long long)generation, | |
292 | (unsigned long long)block_group->key.objectid); | |
2b20982e | 293 | goto free_cache; |
9d66e233 JB |
294 | } |
295 | ||
296 | if (!num_entries) | |
297 | goto out; | |
298 | ||
299 | /* Setup everything for doing checksumming */ | |
300 | num_checksums = i_size_read(inode) / PAGE_CACHE_SIZE; | |
301 | checksums = crc = kzalloc(sizeof(u32) * num_checksums, GFP_NOFS); | |
302 | if (!checksums) | |
303 | goto out; | |
304 | first_page_offset = (sizeof(u32) * num_checksums) + sizeof(u64); | |
305 | disk_crcs = kzalloc(first_page_offset, GFP_NOFS); | |
306 | if (!disk_crcs) | |
307 | goto out; | |
308 | ||
309 | ret = readahead_cache(inode); | |
310 | if (ret) { | |
311 | ret = 0; | |
312 | goto out; | |
313 | } | |
314 | ||
315 | while (1) { | |
316 | struct btrfs_free_space_entry *entry; | |
317 | struct btrfs_free_space *e; | |
318 | void *addr; | |
319 | unsigned long offset = 0; | |
320 | unsigned long start_offset = 0; | |
321 | int need_loop = 0; | |
322 | ||
323 | if (!num_entries && !num_bitmaps) | |
324 | break; | |
325 | ||
326 | if (index == 0) { | |
327 | start_offset = first_page_offset; | |
328 | offset = start_offset; | |
329 | } | |
330 | ||
331 | page = grab_cache_page(inode->i_mapping, index); | |
332 | if (!page) { | |
333 | ret = 0; | |
334 | goto free_cache; | |
335 | } | |
336 | ||
337 | if (!PageUptodate(page)) { | |
338 | btrfs_readpage(NULL, page); | |
339 | lock_page(page); | |
340 | if (!PageUptodate(page)) { | |
341 | unlock_page(page); | |
342 | page_cache_release(page); | |
343 | printk(KERN_ERR "btrfs: error reading free " | |
344 | "space cache: %llu\n", | |
345 | (unsigned long long) | |
346 | block_group->key.objectid); | |
347 | goto free_cache; | |
348 | } | |
349 | } | |
350 | addr = kmap(page); | |
351 | ||
352 | if (index == 0) { | |
353 | u64 *gen; | |
354 | ||
355 | memcpy(disk_crcs, addr, first_page_offset); | |
356 | gen = addr + (sizeof(u32) * num_checksums); | |
357 | if (*gen != BTRFS_I(inode)->generation) { | |
358 | printk(KERN_ERR "btrfs: space cache generation" | |
359 | " (%llu) does not match inode (%llu) " | |
360 | "for block group %llu\n", | |
361 | (unsigned long long)*gen, | |
362 | (unsigned long long) | |
363 | BTRFS_I(inode)->generation, | |
364 | (unsigned long long) | |
365 | block_group->key.objectid); | |
366 | kunmap(page); | |
367 | unlock_page(page); | |
368 | page_cache_release(page); | |
369 | goto free_cache; | |
370 | } | |
371 | crc = (u32 *)disk_crcs; | |
372 | } | |
373 | entry = addr + start_offset; | |
374 | ||
375 | /* First lets check our crc before we do anything fun */ | |
376 | cur_crc = ~(u32)0; | |
377 | cur_crc = btrfs_csum_data(root, addr + start_offset, cur_crc, | |
378 | PAGE_CACHE_SIZE - start_offset); | |
379 | btrfs_csum_final(cur_crc, (char *)&cur_crc); | |
380 | if (cur_crc != *crc) { | |
381 | printk(KERN_ERR "btrfs: crc mismatch for page %lu in " | |
382 | "block group %llu\n", index, | |
383 | (unsigned long long)block_group->key.objectid); | |
384 | kunmap(page); | |
385 | unlock_page(page); | |
386 | page_cache_release(page); | |
387 | goto free_cache; | |
388 | } | |
389 | crc++; | |
390 | ||
391 | while (1) { | |
392 | if (!num_entries) | |
393 | break; | |
394 | ||
395 | need_loop = 1; | |
396 | e = kzalloc(sizeof(struct btrfs_free_space), GFP_NOFS); | |
397 | if (!e) { | |
398 | kunmap(page); | |
399 | unlock_page(page); | |
400 | page_cache_release(page); | |
401 | goto free_cache; | |
402 | } | |
403 | ||
404 | e->offset = le64_to_cpu(entry->offset); | |
405 | e->bytes = le64_to_cpu(entry->bytes); | |
406 | if (!e->bytes) { | |
407 | kunmap(page); | |
408 | kfree(e); | |
409 | unlock_page(page); | |
410 | page_cache_release(page); | |
411 | goto free_cache; | |
412 | } | |
413 | ||
414 | if (entry->type == BTRFS_FREE_SPACE_EXTENT) { | |
415 | spin_lock(&block_group->tree_lock); | |
416 | ret = link_free_space(block_group, e); | |
417 | spin_unlock(&block_group->tree_lock); | |
418 | BUG_ON(ret); | |
419 | } else { | |
420 | e->bitmap = kzalloc(PAGE_CACHE_SIZE, GFP_NOFS); | |
421 | if (!e->bitmap) { | |
422 | kunmap(page); | |
423 | kfree(e); | |
424 | unlock_page(page); | |
425 | page_cache_release(page); | |
426 | goto free_cache; | |
427 | } | |
428 | spin_lock(&block_group->tree_lock); | |
429 | ret = link_free_space(block_group, e); | |
430 | block_group->total_bitmaps++; | |
431 | recalculate_thresholds(block_group); | |
432 | spin_unlock(&block_group->tree_lock); | |
433 | list_add_tail(&e->list, &bitmaps); | |
434 | } | |
435 | ||
436 | num_entries--; | |
437 | offset += sizeof(struct btrfs_free_space_entry); | |
438 | if (offset + sizeof(struct btrfs_free_space_entry) >= | |
439 | PAGE_CACHE_SIZE) | |
440 | break; | |
441 | entry++; | |
442 | } | |
443 | ||
444 | /* | |
445 | * We read an entry out of this page, we need to move on to the | |
446 | * next page. | |
447 | */ | |
448 | if (need_loop) { | |
449 | kunmap(page); | |
450 | goto next; | |
451 | } | |
452 | ||
453 | /* | |
454 | * We add the bitmaps at the end of the entries in order that | |
455 | * the bitmap entries are added to the cache. | |
456 | */ | |
457 | e = list_entry(bitmaps.next, struct btrfs_free_space, list); | |
458 | list_del_init(&e->list); | |
459 | memcpy(e->bitmap, addr, PAGE_CACHE_SIZE); | |
460 | kunmap(page); | |
461 | num_bitmaps--; | |
462 | next: | |
463 | unlock_page(page); | |
464 | page_cache_release(page); | |
465 | index++; | |
466 | } | |
467 | ||
468 | ret = 1; | |
469 | out: | |
470 | kfree(checksums); | |
471 | kfree(disk_crcs); | |
472 | iput(inode); | |
473 | return ret; | |
474 | ||
475 | free_cache: | |
476 | /* This cache is bogus, make sure it gets cleared */ | |
477 | spin_lock(&block_group->lock); | |
478 | block_group->disk_cache_state = BTRFS_DC_CLEAR; | |
479 | spin_unlock(&block_group->lock); | |
480 | btrfs_remove_free_space_cache(block_group); | |
481 | goto out; | |
482 | } | |
483 | ||
0cb59c99 JB |
484 | int btrfs_write_out_cache(struct btrfs_root *root, |
485 | struct btrfs_trans_handle *trans, | |
486 | struct btrfs_block_group_cache *block_group, | |
487 | struct btrfs_path *path) | |
488 | { | |
489 | struct btrfs_free_space_header *header; | |
490 | struct extent_buffer *leaf; | |
491 | struct inode *inode; | |
492 | struct rb_node *node; | |
493 | struct list_head *pos, *n; | |
494 | struct page *page; | |
495 | struct extent_state *cached_state = NULL; | |
496 | struct list_head bitmap_list; | |
497 | struct btrfs_key key; | |
498 | u64 bytes = 0; | |
499 | u32 *crc, *checksums; | |
500 | pgoff_t index = 0, last_index = 0; | |
501 | unsigned long first_page_offset; | |
502 | int num_checksums; | |
503 | int entries = 0; | |
504 | int bitmaps = 0; | |
505 | int ret = 0; | |
506 | ||
507 | root = root->fs_info->tree_root; | |
508 | ||
509 | INIT_LIST_HEAD(&bitmap_list); | |
510 | ||
511 | spin_lock(&block_group->lock); | |
512 | if (block_group->disk_cache_state < BTRFS_DC_SETUP) { | |
513 | spin_unlock(&block_group->lock); | |
514 | return 0; | |
515 | } | |
516 | spin_unlock(&block_group->lock); | |
517 | ||
518 | inode = lookup_free_space_inode(root, block_group, path); | |
519 | if (IS_ERR(inode)) | |
520 | return 0; | |
521 | ||
522 | if (!i_size_read(inode)) { | |
523 | iput(inode); | |
524 | return 0; | |
525 | } | |
526 | ||
2b20982e JB |
527 | node = rb_first(&block_group->free_space_offset); |
528 | if (!node) { | |
529 | iput(inode); | |
530 | return 0; | |
531 | } | |
532 | ||
0cb59c99 JB |
533 | last_index = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT; |
534 | filemap_write_and_wait(inode->i_mapping); | |
535 | btrfs_wait_ordered_range(inode, inode->i_size & | |
536 | ~(root->sectorsize - 1), (u64)-1); | |
537 | ||
538 | /* We need a checksum per page. */ | |
539 | num_checksums = i_size_read(inode) / PAGE_CACHE_SIZE; | |
540 | crc = checksums = kzalloc(sizeof(u32) * num_checksums, GFP_NOFS); | |
541 | if (!crc) { | |
542 | iput(inode); | |
543 | return 0; | |
544 | } | |
545 | ||
546 | /* Since the first page has all of our checksums and our generation we | |
547 | * need to calculate the offset into the page that we can start writing | |
548 | * our entries. | |
549 | */ | |
550 | first_page_offset = (sizeof(u32) * num_checksums) + sizeof(u64); | |
551 | ||
0cb59c99 JB |
552 | /* |
553 | * Lock all pages first so we can lock the extent safely. | |
554 | * | |
555 | * NOTE: Because we hold the ref the entire time we're going to write to | |
556 | * the page find_get_page should never fail, so we don't do a check | |
557 | * after find_get_page at this point. Just putting this here so people | |
558 | * know and don't freak out. | |
559 | */ | |
560 | while (index <= last_index) { | |
561 | page = grab_cache_page(inode->i_mapping, index); | |
562 | if (!page) { | |
563 | pgoff_t i = 0; | |
564 | ||
565 | while (i < index) { | |
566 | page = find_get_page(inode->i_mapping, i); | |
567 | unlock_page(page); | |
568 | page_cache_release(page); | |
569 | page_cache_release(page); | |
570 | i++; | |
571 | } | |
572 | goto out_free; | |
573 | } | |
574 | index++; | |
575 | } | |
576 | ||
577 | index = 0; | |
578 | lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1, | |
579 | 0, &cached_state, GFP_NOFS); | |
580 | ||
581 | /* Write out the extent entries */ | |
582 | do { | |
583 | struct btrfs_free_space_entry *entry; | |
584 | void *addr; | |
585 | unsigned long offset = 0; | |
586 | unsigned long start_offset = 0; | |
587 | ||
588 | if (index == 0) { | |
589 | start_offset = first_page_offset; | |
590 | offset = start_offset; | |
591 | } | |
592 | ||
593 | page = find_get_page(inode->i_mapping, index); | |
594 | ||
595 | addr = kmap(page); | |
596 | entry = addr + start_offset; | |
597 | ||
598 | memset(addr, 0, PAGE_CACHE_SIZE); | |
599 | while (1) { | |
600 | struct btrfs_free_space *e; | |
601 | ||
602 | e = rb_entry(node, struct btrfs_free_space, offset_index); | |
603 | entries++; | |
604 | ||
605 | entry->offset = cpu_to_le64(e->offset); | |
606 | entry->bytes = cpu_to_le64(e->bytes); | |
607 | if (e->bitmap) { | |
608 | entry->type = BTRFS_FREE_SPACE_BITMAP; | |
609 | list_add_tail(&e->list, &bitmap_list); | |
610 | bitmaps++; | |
611 | } else { | |
612 | entry->type = BTRFS_FREE_SPACE_EXTENT; | |
613 | } | |
614 | node = rb_next(node); | |
615 | if (!node) | |
616 | break; | |
617 | offset += sizeof(struct btrfs_free_space_entry); | |
618 | if (offset + sizeof(struct btrfs_free_space_entry) >= | |
619 | PAGE_CACHE_SIZE) | |
620 | break; | |
621 | entry++; | |
622 | } | |
623 | *crc = ~(u32)0; | |
624 | *crc = btrfs_csum_data(root, addr + start_offset, *crc, | |
625 | PAGE_CACHE_SIZE - start_offset); | |
626 | kunmap(page); | |
627 | ||
628 | btrfs_csum_final(*crc, (char *)crc); | |
629 | crc++; | |
630 | ||
631 | bytes += PAGE_CACHE_SIZE; | |
632 | ||
633 | ClearPageChecked(page); | |
634 | set_page_extent_mapped(page); | |
635 | SetPageUptodate(page); | |
636 | set_page_dirty(page); | |
637 | ||
638 | /* | |
639 | * We need to release our reference we got for grab_cache_page, | |
640 | * except for the first page which will hold our checksums, we | |
641 | * do that below. | |
642 | */ | |
643 | if (index != 0) { | |
644 | unlock_page(page); | |
645 | page_cache_release(page); | |
646 | } | |
647 | ||
648 | page_cache_release(page); | |
649 | ||
650 | index++; | |
651 | } while (node); | |
652 | ||
653 | /* Write out the bitmaps */ | |
654 | list_for_each_safe(pos, n, &bitmap_list) { | |
655 | void *addr; | |
656 | struct btrfs_free_space *entry = | |
657 | list_entry(pos, struct btrfs_free_space, list); | |
658 | ||
659 | page = find_get_page(inode->i_mapping, index); | |
660 | ||
661 | addr = kmap(page); | |
662 | memcpy(addr, entry->bitmap, PAGE_CACHE_SIZE); | |
663 | *crc = ~(u32)0; | |
664 | *crc = btrfs_csum_data(root, addr, *crc, PAGE_CACHE_SIZE); | |
665 | kunmap(page); | |
666 | btrfs_csum_final(*crc, (char *)crc); | |
667 | crc++; | |
668 | bytes += PAGE_CACHE_SIZE; | |
669 | ||
670 | ClearPageChecked(page); | |
671 | set_page_extent_mapped(page); | |
672 | SetPageUptodate(page); | |
673 | set_page_dirty(page); | |
674 | unlock_page(page); | |
675 | page_cache_release(page); | |
676 | page_cache_release(page); | |
677 | list_del_init(&entry->list); | |
678 | index++; | |
679 | } | |
680 | ||
681 | /* Zero out the rest of the pages just to make sure */ | |
682 | while (index <= last_index) { | |
683 | void *addr; | |
684 | ||
685 | page = find_get_page(inode->i_mapping, index); | |
686 | ||
687 | addr = kmap(page); | |
688 | memset(addr, 0, PAGE_CACHE_SIZE); | |
689 | kunmap(page); | |
690 | ClearPageChecked(page); | |
691 | set_page_extent_mapped(page); | |
692 | SetPageUptodate(page); | |
693 | set_page_dirty(page); | |
694 | unlock_page(page); | |
695 | page_cache_release(page); | |
696 | page_cache_release(page); | |
697 | bytes += PAGE_CACHE_SIZE; | |
698 | index++; | |
699 | } | |
700 | ||
701 | btrfs_set_extent_delalloc(inode, 0, bytes - 1, &cached_state); | |
702 | ||
703 | /* Write the checksums and trans id to the first page */ | |
704 | { | |
705 | void *addr; | |
706 | u64 *gen; | |
707 | ||
708 | page = find_get_page(inode->i_mapping, 0); | |
709 | ||
710 | addr = kmap(page); | |
711 | memcpy(addr, checksums, sizeof(u32) * num_checksums); | |
712 | gen = addr + (sizeof(u32) * num_checksums); | |
713 | *gen = trans->transid; | |
714 | kunmap(page); | |
715 | ClearPageChecked(page); | |
716 | set_page_extent_mapped(page); | |
717 | SetPageUptodate(page); | |
718 | set_page_dirty(page); | |
719 | unlock_page(page); | |
720 | page_cache_release(page); | |
721 | page_cache_release(page); | |
722 | } | |
723 | BTRFS_I(inode)->generation = trans->transid; | |
724 | ||
725 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, 0, | |
726 | i_size_read(inode) - 1, &cached_state, GFP_NOFS); | |
727 | ||
728 | filemap_write_and_wait(inode->i_mapping); | |
729 | ||
730 | key.objectid = BTRFS_FREE_SPACE_OBJECTID; | |
731 | key.offset = block_group->key.objectid; | |
732 | key.type = 0; | |
733 | ||
734 | ret = btrfs_search_slot(trans, root, &key, path, 1, 1); | |
735 | if (ret < 0) { | |
736 | ret = 0; | |
737 | clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, bytes - 1, | |
738 | EXTENT_DIRTY | EXTENT_DELALLOC | | |
739 | EXTENT_DO_ACCOUNTING, 0, 0, NULL, GFP_NOFS); | |
740 | goto out_free; | |
741 | } | |
742 | leaf = path->nodes[0]; | |
743 | if (ret > 0) { | |
744 | struct btrfs_key found_key; | |
745 | BUG_ON(!path->slots[0]); | |
746 | path->slots[0]--; | |
747 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
748 | if (found_key.objectid != BTRFS_FREE_SPACE_OBJECTID || | |
749 | found_key.offset != block_group->key.objectid) { | |
750 | ret = 0; | |
751 | clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, bytes - 1, | |
752 | EXTENT_DIRTY | EXTENT_DELALLOC | | |
753 | EXTENT_DO_ACCOUNTING, 0, 0, NULL, | |
754 | GFP_NOFS); | |
755 | btrfs_release_path(root, path); | |
756 | goto out_free; | |
757 | } | |
758 | } | |
759 | header = btrfs_item_ptr(leaf, path->slots[0], | |
760 | struct btrfs_free_space_header); | |
761 | btrfs_set_free_space_entries(leaf, header, entries); | |
762 | btrfs_set_free_space_bitmaps(leaf, header, bitmaps); | |
763 | btrfs_set_free_space_generation(leaf, header, trans->transid); | |
764 | btrfs_mark_buffer_dirty(leaf); | |
765 | btrfs_release_path(root, path); | |
766 | ||
767 | ret = 1; | |
768 | ||
769 | out_free: | |
770 | if (ret == 0) { | |
771 | invalidate_inode_pages2_range(inode->i_mapping, 0, index); | |
772 | spin_lock(&block_group->lock); | |
773 | block_group->disk_cache_state = BTRFS_DC_ERROR; | |
774 | spin_unlock(&block_group->lock); | |
775 | BTRFS_I(inode)->generation = 0; | |
776 | } | |
777 | kfree(checksums); | |
778 | btrfs_update_inode(trans, root, inode); | |
779 | iput(inode); | |
780 | return ret; | |
781 | } | |
782 | ||
96303081 JB |
783 | static inline unsigned long offset_to_bit(u64 bitmap_start, u64 sectorsize, |
784 | u64 offset) | |
0f9dd46c | 785 | { |
96303081 JB |
786 | BUG_ON(offset < bitmap_start); |
787 | offset -= bitmap_start; | |
788 | return (unsigned long)(div64_u64(offset, sectorsize)); | |
789 | } | |
0f9dd46c | 790 | |
96303081 JB |
791 | static inline unsigned long bytes_to_bits(u64 bytes, u64 sectorsize) |
792 | { | |
793 | return (unsigned long)(div64_u64(bytes, sectorsize)); | |
794 | } | |
0f9dd46c | 795 | |
96303081 JB |
796 | static inline u64 offset_to_bitmap(struct btrfs_block_group_cache *block_group, |
797 | u64 offset) | |
798 | { | |
799 | u64 bitmap_start; | |
800 | u64 bytes_per_bitmap; | |
0f9dd46c | 801 | |
96303081 JB |
802 | bytes_per_bitmap = BITS_PER_BITMAP * block_group->sectorsize; |
803 | bitmap_start = offset - block_group->key.objectid; | |
804 | bitmap_start = div64_u64(bitmap_start, bytes_per_bitmap); | |
805 | bitmap_start *= bytes_per_bitmap; | |
806 | bitmap_start += block_group->key.objectid; | |
0f9dd46c | 807 | |
96303081 | 808 | return bitmap_start; |
0f9dd46c JB |
809 | } |
810 | ||
96303081 JB |
811 | static int tree_insert_offset(struct rb_root *root, u64 offset, |
812 | struct rb_node *node, int bitmap) | |
0f9dd46c JB |
813 | { |
814 | struct rb_node **p = &root->rb_node; | |
815 | struct rb_node *parent = NULL; | |
816 | struct btrfs_free_space *info; | |
817 | ||
818 | while (*p) { | |
819 | parent = *p; | |
96303081 | 820 | info = rb_entry(parent, struct btrfs_free_space, offset_index); |
0f9dd46c | 821 | |
96303081 | 822 | if (offset < info->offset) { |
0f9dd46c | 823 | p = &(*p)->rb_left; |
96303081 | 824 | } else if (offset > info->offset) { |
0f9dd46c | 825 | p = &(*p)->rb_right; |
96303081 JB |
826 | } else { |
827 | /* | |
828 | * we could have a bitmap entry and an extent entry | |
829 | * share the same offset. If this is the case, we want | |
830 | * the extent entry to always be found first if we do a | |
831 | * linear search through the tree, since we want to have | |
832 | * the quickest allocation time, and allocating from an | |
833 | * extent is faster than allocating from a bitmap. So | |
834 | * if we're inserting a bitmap and we find an entry at | |
835 | * this offset, we want to go right, or after this entry | |
836 | * logically. If we are inserting an extent and we've | |
837 | * found a bitmap, we want to go left, or before | |
838 | * logically. | |
839 | */ | |
840 | if (bitmap) { | |
841 | WARN_ON(info->bitmap); | |
842 | p = &(*p)->rb_right; | |
843 | } else { | |
844 | WARN_ON(!info->bitmap); | |
845 | p = &(*p)->rb_left; | |
846 | } | |
847 | } | |
0f9dd46c JB |
848 | } |
849 | ||
850 | rb_link_node(node, parent, p); | |
851 | rb_insert_color(node, root); | |
852 | ||
853 | return 0; | |
854 | } | |
855 | ||
856 | /* | |
70cb0743 JB |
857 | * searches the tree for the given offset. |
858 | * | |
96303081 JB |
859 | * fuzzy - If this is set, then we are trying to make an allocation, and we just |
860 | * want a section that has at least bytes size and comes at or after the given | |
861 | * offset. | |
0f9dd46c | 862 | */ |
96303081 JB |
863 | static struct btrfs_free_space * |
864 | tree_search_offset(struct btrfs_block_group_cache *block_group, | |
865 | u64 offset, int bitmap_only, int fuzzy) | |
0f9dd46c | 866 | { |
96303081 JB |
867 | struct rb_node *n = block_group->free_space_offset.rb_node; |
868 | struct btrfs_free_space *entry, *prev = NULL; | |
869 | ||
870 | /* find entry that is closest to the 'offset' */ | |
871 | while (1) { | |
872 | if (!n) { | |
873 | entry = NULL; | |
874 | break; | |
875 | } | |
0f9dd46c | 876 | |
0f9dd46c | 877 | entry = rb_entry(n, struct btrfs_free_space, offset_index); |
96303081 | 878 | prev = entry; |
0f9dd46c | 879 | |
96303081 | 880 | if (offset < entry->offset) |
0f9dd46c | 881 | n = n->rb_left; |
96303081 | 882 | else if (offset > entry->offset) |
0f9dd46c | 883 | n = n->rb_right; |
96303081 | 884 | else |
0f9dd46c | 885 | break; |
0f9dd46c JB |
886 | } |
887 | ||
96303081 JB |
888 | if (bitmap_only) { |
889 | if (!entry) | |
890 | return NULL; | |
891 | if (entry->bitmap) | |
892 | return entry; | |
0f9dd46c | 893 | |
96303081 JB |
894 | /* |
895 | * bitmap entry and extent entry may share same offset, | |
896 | * in that case, bitmap entry comes after extent entry. | |
897 | */ | |
898 | n = rb_next(n); | |
899 | if (!n) | |
900 | return NULL; | |
901 | entry = rb_entry(n, struct btrfs_free_space, offset_index); | |
902 | if (entry->offset != offset) | |
903 | return NULL; | |
0f9dd46c | 904 | |
96303081 JB |
905 | WARN_ON(!entry->bitmap); |
906 | return entry; | |
907 | } else if (entry) { | |
908 | if (entry->bitmap) { | |
0f9dd46c | 909 | /* |
96303081 JB |
910 | * if previous extent entry covers the offset, |
911 | * we should return it instead of the bitmap entry | |
0f9dd46c | 912 | */ |
96303081 JB |
913 | n = &entry->offset_index; |
914 | while (1) { | |
915 | n = rb_prev(n); | |
916 | if (!n) | |
917 | break; | |
918 | prev = rb_entry(n, struct btrfs_free_space, | |
919 | offset_index); | |
920 | if (!prev->bitmap) { | |
921 | if (prev->offset + prev->bytes > offset) | |
922 | entry = prev; | |
923 | break; | |
924 | } | |
0f9dd46c | 925 | } |
96303081 JB |
926 | } |
927 | return entry; | |
928 | } | |
929 | ||
930 | if (!prev) | |
931 | return NULL; | |
932 | ||
933 | /* find last entry before the 'offset' */ | |
934 | entry = prev; | |
935 | if (entry->offset > offset) { | |
936 | n = rb_prev(&entry->offset_index); | |
937 | if (n) { | |
938 | entry = rb_entry(n, struct btrfs_free_space, | |
939 | offset_index); | |
940 | BUG_ON(entry->offset > offset); | |
0f9dd46c | 941 | } else { |
96303081 JB |
942 | if (fuzzy) |
943 | return entry; | |
944 | else | |
945 | return NULL; | |
0f9dd46c JB |
946 | } |
947 | } | |
948 | ||
96303081 JB |
949 | if (entry->bitmap) { |
950 | n = &entry->offset_index; | |
951 | while (1) { | |
952 | n = rb_prev(n); | |
953 | if (!n) | |
954 | break; | |
955 | prev = rb_entry(n, struct btrfs_free_space, | |
956 | offset_index); | |
957 | if (!prev->bitmap) { | |
958 | if (prev->offset + prev->bytes > offset) | |
959 | return prev; | |
960 | break; | |
961 | } | |
962 | } | |
963 | if (entry->offset + BITS_PER_BITMAP * | |
964 | block_group->sectorsize > offset) | |
965 | return entry; | |
966 | } else if (entry->offset + entry->bytes > offset) | |
967 | return entry; | |
968 | ||
969 | if (!fuzzy) | |
970 | return NULL; | |
971 | ||
972 | while (1) { | |
973 | if (entry->bitmap) { | |
974 | if (entry->offset + BITS_PER_BITMAP * | |
975 | block_group->sectorsize > offset) | |
976 | break; | |
977 | } else { | |
978 | if (entry->offset + entry->bytes > offset) | |
979 | break; | |
980 | } | |
981 | ||
982 | n = rb_next(&entry->offset_index); | |
983 | if (!n) | |
984 | return NULL; | |
985 | entry = rb_entry(n, struct btrfs_free_space, offset_index); | |
986 | } | |
987 | return entry; | |
0f9dd46c JB |
988 | } |
989 | ||
f333adb5 LZ |
990 | static inline void |
991 | __unlink_free_space(struct btrfs_block_group_cache *block_group, | |
992 | struct btrfs_free_space *info) | |
0f9dd46c JB |
993 | { |
994 | rb_erase(&info->offset_index, &block_group->free_space_offset); | |
96303081 | 995 | block_group->free_extents--; |
f333adb5 LZ |
996 | } |
997 | ||
998 | static void unlink_free_space(struct btrfs_block_group_cache *block_group, | |
999 | struct btrfs_free_space *info) | |
1000 | { | |
1001 | __unlink_free_space(block_group, info); | |
817d52f8 | 1002 | block_group->free_space -= info->bytes; |
0f9dd46c JB |
1003 | } |
1004 | ||
1005 | static int link_free_space(struct btrfs_block_group_cache *block_group, | |
1006 | struct btrfs_free_space *info) | |
1007 | { | |
1008 | int ret = 0; | |
1009 | ||
96303081 | 1010 | BUG_ON(!info->bitmap && !info->bytes); |
0f9dd46c | 1011 | ret = tree_insert_offset(&block_group->free_space_offset, info->offset, |
96303081 | 1012 | &info->offset_index, (info->bitmap != NULL)); |
0f9dd46c JB |
1013 | if (ret) |
1014 | return ret; | |
1015 | ||
817d52f8 | 1016 | block_group->free_space += info->bytes; |
96303081 JB |
1017 | block_group->free_extents++; |
1018 | return ret; | |
1019 | } | |
1020 | ||
1021 | static void recalculate_thresholds(struct btrfs_block_group_cache *block_group) | |
1022 | { | |
25891f79 JB |
1023 | u64 max_bytes; |
1024 | u64 bitmap_bytes; | |
1025 | u64 extent_bytes; | |
8eb2d829 | 1026 | u64 size = block_group->key.offset; |
96303081 JB |
1027 | |
1028 | /* | |
1029 | * The goal is to keep the total amount of memory used per 1gb of space | |
1030 | * at or below 32k, so we need to adjust how much memory we allow to be | |
1031 | * used by extent based free space tracking | |
1032 | */ | |
8eb2d829 LZ |
1033 | if (size < 1024 * 1024 * 1024) |
1034 | max_bytes = MAX_CACHE_BYTES_PER_GIG; | |
1035 | else | |
1036 | max_bytes = MAX_CACHE_BYTES_PER_GIG * | |
1037 | div64_u64(size, 1024 * 1024 * 1024); | |
96303081 | 1038 | |
25891f79 JB |
1039 | /* |
1040 | * we want to account for 1 more bitmap than what we have so we can make | |
1041 | * sure we don't go over our overall goal of MAX_CACHE_BYTES_PER_GIG as | |
1042 | * we add more bitmaps. | |
1043 | */ | |
1044 | bitmap_bytes = (block_group->total_bitmaps + 1) * PAGE_CACHE_SIZE; | |
96303081 | 1045 | |
25891f79 JB |
1046 | if (bitmap_bytes >= max_bytes) { |
1047 | block_group->extents_thresh = 0; | |
1048 | return; | |
1049 | } | |
96303081 | 1050 | |
25891f79 JB |
1051 | /* |
1052 | * we want the extent entry threshold to always be at most 1/2 the maxw | |
1053 | * bytes we can have, or whatever is less than that. | |
1054 | */ | |
1055 | extent_bytes = max_bytes - bitmap_bytes; | |
1056 | extent_bytes = min_t(u64, extent_bytes, div64_u64(max_bytes, 2)); | |
96303081 | 1057 | |
25891f79 JB |
1058 | block_group->extents_thresh = |
1059 | div64_u64(extent_bytes, (sizeof(struct btrfs_free_space))); | |
96303081 JB |
1060 | } |
1061 | ||
817d52f8 JB |
1062 | static void bitmap_clear_bits(struct btrfs_block_group_cache *block_group, |
1063 | struct btrfs_free_space *info, u64 offset, | |
1064 | u64 bytes) | |
96303081 JB |
1065 | { |
1066 | unsigned long start, end; | |
1067 | unsigned long i; | |
1068 | ||
817d52f8 JB |
1069 | start = offset_to_bit(info->offset, block_group->sectorsize, offset); |
1070 | end = start + bytes_to_bits(bytes, block_group->sectorsize); | |
96303081 JB |
1071 | BUG_ON(end > BITS_PER_BITMAP); |
1072 | ||
1073 | for (i = start; i < end; i++) | |
1074 | clear_bit(i, info->bitmap); | |
1075 | ||
1076 | info->bytes -= bytes; | |
817d52f8 | 1077 | block_group->free_space -= bytes; |
96303081 JB |
1078 | } |
1079 | ||
817d52f8 JB |
1080 | static void bitmap_set_bits(struct btrfs_block_group_cache *block_group, |
1081 | struct btrfs_free_space *info, u64 offset, | |
1082 | u64 bytes) | |
96303081 JB |
1083 | { |
1084 | unsigned long start, end; | |
1085 | unsigned long i; | |
1086 | ||
817d52f8 JB |
1087 | start = offset_to_bit(info->offset, block_group->sectorsize, offset); |
1088 | end = start + bytes_to_bits(bytes, block_group->sectorsize); | |
96303081 JB |
1089 | BUG_ON(end > BITS_PER_BITMAP); |
1090 | ||
1091 | for (i = start; i < end; i++) | |
1092 | set_bit(i, info->bitmap); | |
1093 | ||
1094 | info->bytes += bytes; | |
817d52f8 | 1095 | block_group->free_space += bytes; |
96303081 JB |
1096 | } |
1097 | ||
1098 | static int search_bitmap(struct btrfs_block_group_cache *block_group, | |
1099 | struct btrfs_free_space *bitmap_info, u64 *offset, | |
1100 | u64 *bytes) | |
1101 | { | |
1102 | unsigned long found_bits = 0; | |
1103 | unsigned long bits, i; | |
1104 | unsigned long next_zero; | |
1105 | ||
1106 | i = offset_to_bit(bitmap_info->offset, block_group->sectorsize, | |
1107 | max_t(u64, *offset, bitmap_info->offset)); | |
1108 | bits = bytes_to_bits(*bytes, block_group->sectorsize); | |
1109 | ||
1110 | for (i = find_next_bit(bitmap_info->bitmap, BITS_PER_BITMAP, i); | |
1111 | i < BITS_PER_BITMAP; | |
1112 | i = find_next_bit(bitmap_info->bitmap, BITS_PER_BITMAP, i + 1)) { | |
1113 | next_zero = find_next_zero_bit(bitmap_info->bitmap, | |
1114 | BITS_PER_BITMAP, i); | |
1115 | if ((next_zero - i) >= bits) { | |
1116 | found_bits = next_zero - i; | |
1117 | break; | |
1118 | } | |
1119 | i = next_zero; | |
1120 | } | |
1121 | ||
1122 | if (found_bits) { | |
1123 | *offset = (u64)(i * block_group->sectorsize) + | |
1124 | bitmap_info->offset; | |
1125 | *bytes = (u64)(found_bits) * block_group->sectorsize; | |
1126 | return 0; | |
1127 | } | |
1128 | ||
1129 | return -1; | |
1130 | } | |
1131 | ||
1132 | static struct btrfs_free_space *find_free_space(struct btrfs_block_group_cache | |
1133 | *block_group, u64 *offset, | |
1134 | u64 *bytes, int debug) | |
1135 | { | |
1136 | struct btrfs_free_space *entry; | |
1137 | struct rb_node *node; | |
1138 | int ret; | |
1139 | ||
1140 | if (!block_group->free_space_offset.rb_node) | |
1141 | return NULL; | |
1142 | ||
1143 | entry = tree_search_offset(block_group, | |
1144 | offset_to_bitmap(block_group, *offset), | |
1145 | 0, 1); | |
1146 | if (!entry) | |
1147 | return NULL; | |
1148 | ||
1149 | for (node = &entry->offset_index; node; node = rb_next(node)) { | |
1150 | entry = rb_entry(node, struct btrfs_free_space, offset_index); | |
1151 | if (entry->bytes < *bytes) | |
1152 | continue; | |
1153 | ||
1154 | if (entry->bitmap) { | |
1155 | ret = search_bitmap(block_group, entry, offset, bytes); | |
1156 | if (!ret) | |
1157 | return entry; | |
1158 | continue; | |
1159 | } | |
1160 | ||
1161 | *offset = entry->offset; | |
1162 | *bytes = entry->bytes; | |
1163 | return entry; | |
1164 | } | |
1165 | ||
1166 | return NULL; | |
1167 | } | |
1168 | ||
1169 | static void add_new_bitmap(struct btrfs_block_group_cache *block_group, | |
1170 | struct btrfs_free_space *info, u64 offset) | |
1171 | { | |
1172 | u64 bytes_per_bg = BITS_PER_BITMAP * block_group->sectorsize; | |
1173 | int max_bitmaps = (int)div64_u64(block_group->key.offset + | |
1174 | bytes_per_bg - 1, bytes_per_bg); | |
1175 | BUG_ON(block_group->total_bitmaps >= max_bitmaps); | |
1176 | ||
1177 | info->offset = offset_to_bitmap(block_group, offset); | |
f019f426 | 1178 | info->bytes = 0; |
96303081 JB |
1179 | link_free_space(block_group, info); |
1180 | block_group->total_bitmaps++; | |
1181 | ||
1182 | recalculate_thresholds(block_group); | |
1183 | } | |
1184 | ||
edf6e2d1 LZ |
1185 | static void free_bitmap(struct btrfs_block_group_cache *block_group, |
1186 | struct btrfs_free_space *bitmap_info) | |
1187 | { | |
1188 | unlink_free_space(block_group, bitmap_info); | |
1189 | kfree(bitmap_info->bitmap); | |
1190 | kfree(bitmap_info); | |
1191 | block_group->total_bitmaps--; | |
1192 | recalculate_thresholds(block_group); | |
1193 | } | |
1194 | ||
96303081 JB |
1195 | static noinline int remove_from_bitmap(struct btrfs_block_group_cache *block_group, |
1196 | struct btrfs_free_space *bitmap_info, | |
1197 | u64 *offset, u64 *bytes) | |
1198 | { | |
1199 | u64 end; | |
6606bb97 JB |
1200 | u64 search_start, search_bytes; |
1201 | int ret; | |
96303081 JB |
1202 | |
1203 | again: | |
1204 | end = bitmap_info->offset + | |
1205 | (u64)(BITS_PER_BITMAP * block_group->sectorsize) - 1; | |
1206 | ||
6606bb97 JB |
1207 | /* |
1208 | * XXX - this can go away after a few releases. | |
1209 | * | |
1210 | * since the only user of btrfs_remove_free_space is the tree logging | |
1211 | * stuff, and the only way to test that is under crash conditions, we | |
1212 | * want to have this debug stuff here just in case somethings not | |
1213 | * working. Search the bitmap for the space we are trying to use to | |
1214 | * make sure its actually there. If its not there then we need to stop | |
1215 | * because something has gone wrong. | |
1216 | */ | |
1217 | search_start = *offset; | |
1218 | search_bytes = *bytes; | |
13dbc089 | 1219 | search_bytes = min(search_bytes, end - search_start + 1); |
6606bb97 JB |
1220 | ret = search_bitmap(block_group, bitmap_info, &search_start, |
1221 | &search_bytes); | |
1222 | BUG_ON(ret < 0 || search_start != *offset); | |
1223 | ||
96303081 | 1224 | if (*offset > bitmap_info->offset && *offset + *bytes > end) { |
817d52f8 JB |
1225 | bitmap_clear_bits(block_group, bitmap_info, *offset, |
1226 | end - *offset + 1); | |
96303081 JB |
1227 | *bytes -= end - *offset + 1; |
1228 | *offset = end + 1; | |
1229 | } else if (*offset >= bitmap_info->offset && *offset + *bytes <= end) { | |
817d52f8 | 1230 | bitmap_clear_bits(block_group, bitmap_info, *offset, *bytes); |
96303081 JB |
1231 | *bytes = 0; |
1232 | } | |
1233 | ||
1234 | if (*bytes) { | |
6606bb97 | 1235 | struct rb_node *next = rb_next(&bitmap_info->offset_index); |
edf6e2d1 LZ |
1236 | if (!bitmap_info->bytes) |
1237 | free_bitmap(block_group, bitmap_info); | |
96303081 | 1238 | |
6606bb97 JB |
1239 | /* |
1240 | * no entry after this bitmap, but we still have bytes to | |
1241 | * remove, so something has gone wrong. | |
1242 | */ | |
1243 | if (!next) | |
96303081 JB |
1244 | return -EINVAL; |
1245 | ||
6606bb97 JB |
1246 | bitmap_info = rb_entry(next, struct btrfs_free_space, |
1247 | offset_index); | |
1248 | ||
1249 | /* | |
1250 | * if the next entry isn't a bitmap we need to return to let the | |
1251 | * extent stuff do its work. | |
1252 | */ | |
96303081 JB |
1253 | if (!bitmap_info->bitmap) |
1254 | return -EAGAIN; | |
1255 | ||
6606bb97 JB |
1256 | /* |
1257 | * Ok the next item is a bitmap, but it may not actually hold | |
1258 | * the information for the rest of this free space stuff, so | |
1259 | * look for it, and if we don't find it return so we can try | |
1260 | * everything over again. | |
1261 | */ | |
1262 | search_start = *offset; | |
1263 | search_bytes = *bytes; | |
1264 | ret = search_bitmap(block_group, bitmap_info, &search_start, | |
1265 | &search_bytes); | |
1266 | if (ret < 0 || search_start != *offset) | |
1267 | return -EAGAIN; | |
1268 | ||
96303081 | 1269 | goto again; |
edf6e2d1 LZ |
1270 | } else if (!bitmap_info->bytes) |
1271 | free_bitmap(block_group, bitmap_info); | |
96303081 JB |
1272 | |
1273 | return 0; | |
1274 | } | |
1275 | ||
1276 | static int insert_into_bitmap(struct btrfs_block_group_cache *block_group, | |
1277 | struct btrfs_free_space *info) | |
1278 | { | |
1279 | struct btrfs_free_space *bitmap_info; | |
1280 | int added = 0; | |
1281 | u64 bytes, offset, end; | |
1282 | int ret; | |
1283 | ||
1284 | /* | |
1285 | * If we are below the extents threshold then we can add this as an | |
1286 | * extent, and don't have to deal with the bitmap | |
1287 | */ | |
1288 | if (block_group->free_extents < block_group->extents_thresh && | |
1289 | info->bytes > block_group->sectorsize * 4) | |
1290 | return 0; | |
1291 | ||
1292 | /* | |
1293 | * some block groups are so tiny they can't be enveloped by a bitmap, so | |
1294 | * don't even bother to create a bitmap for this | |
1295 | */ | |
1296 | if (BITS_PER_BITMAP * block_group->sectorsize > | |
1297 | block_group->key.offset) | |
1298 | return 0; | |
1299 | ||
1300 | bytes = info->bytes; | |
1301 | offset = info->offset; | |
1302 | ||
1303 | again: | |
1304 | bitmap_info = tree_search_offset(block_group, | |
1305 | offset_to_bitmap(block_group, offset), | |
1306 | 1, 0); | |
1307 | if (!bitmap_info) { | |
1308 | BUG_ON(added); | |
1309 | goto new_bitmap; | |
1310 | } | |
1311 | ||
1312 | end = bitmap_info->offset + | |
1313 | (u64)(BITS_PER_BITMAP * block_group->sectorsize); | |
1314 | ||
1315 | if (offset >= bitmap_info->offset && offset + bytes > end) { | |
817d52f8 JB |
1316 | bitmap_set_bits(block_group, bitmap_info, offset, |
1317 | end - offset); | |
96303081 JB |
1318 | bytes -= end - offset; |
1319 | offset = end; | |
1320 | added = 0; | |
1321 | } else if (offset >= bitmap_info->offset && offset + bytes <= end) { | |
817d52f8 | 1322 | bitmap_set_bits(block_group, bitmap_info, offset, bytes); |
96303081 JB |
1323 | bytes = 0; |
1324 | } else { | |
1325 | BUG(); | |
1326 | } | |
1327 | ||
1328 | if (!bytes) { | |
1329 | ret = 1; | |
1330 | goto out; | |
1331 | } else | |
1332 | goto again; | |
1333 | ||
1334 | new_bitmap: | |
1335 | if (info && info->bitmap) { | |
1336 | add_new_bitmap(block_group, info, offset); | |
1337 | added = 1; | |
1338 | info = NULL; | |
1339 | goto again; | |
1340 | } else { | |
1341 | spin_unlock(&block_group->tree_lock); | |
1342 | ||
1343 | /* no pre-allocated info, allocate a new one */ | |
1344 | if (!info) { | |
1345 | info = kzalloc(sizeof(struct btrfs_free_space), | |
1346 | GFP_NOFS); | |
1347 | if (!info) { | |
1348 | spin_lock(&block_group->tree_lock); | |
1349 | ret = -ENOMEM; | |
1350 | goto out; | |
1351 | } | |
1352 | } | |
1353 | ||
1354 | /* allocate the bitmap */ | |
1355 | info->bitmap = kzalloc(PAGE_CACHE_SIZE, GFP_NOFS); | |
1356 | spin_lock(&block_group->tree_lock); | |
1357 | if (!info->bitmap) { | |
1358 | ret = -ENOMEM; | |
1359 | goto out; | |
1360 | } | |
1361 | goto again; | |
1362 | } | |
1363 | ||
1364 | out: | |
1365 | if (info) { | |
1366 | if (info->bitmap) | |
1367 | kfree(info->bitmap); | |
1368 | kfree(info); | |
1369 | } | |
0f9dd46c JB |
1370 | |
1371 | return ret; | |
1372 | } | |
1373 | ||
120d66ee | 1374 | bool try_merge_free_space(struct btrfs_block_group_cache *block_group, |
f333adb5 | 1375 | struct btrfs_free_space *info, bool update_stat) |
0f9dd46c | 1376 | { |
120d66ee LZ |
1377 | struct btrfs_free_space *left_info; |
1378 | struct btrfs_free_space *right_info; | |
1379 | bool merged = false; | |
1380 | u64 offset = info->offset; | |
1381 | u64 bytes = info->bytes; | |
6226cb0a | 1382 | |
0f9dd46c JB |
1383 | /* |
1384 | * first we want to see if there is free space adjacent to the range we | |
1385 | * are adding, if there is remove that struct and add a new one to | |
1386 | * cover the entire range | |
1387 | */ | |
96303081 JB |
1388 | right_info = tree_search_offset(block_group, offset + bytes, 0, 0); |
1389 | if (right_info && rb_prev(&right_info->offset_index)) | |
1390 | left_info = rb_entry(rb_prev(&right_info->offset_index), | |
1391 | struct btrfs_free_space, offset_index); | |
1392 | else | |
1393 | left_info = tree_search_offset(block_group, offset - 1, 0, 0); | |
0f9dd46c | 1394 | |
96303081 | 1395 | if (right_info && !right_info->bitmap) { |
f333adb5 LZ |
1396 | if (update_stat) |
1397 | unlink_free_space(block_group, right_info); | |
1398 | else | |
1399 | __unlink_free_space(block_group, right_info); | |
6226cb0a JB |
1400 | info->bytes += right_info->bytes; |
1401 | kfree(right_info); | |
120d66ee | 1402 | merged = true; |
0f9dd46c JB |
1403 | } |
1404 | ||
96303081 JB |
1405 | if (left_info && !left_info->bitmap && |
1406 | left_info->offset + left_info->bytes == offset) { | |
f333adb5 LZ |
1407 | if (update_stat) |
1408 | unlink_free_space(block_group, left_info); | |
1409 | else | |
1410 | __unlink_free_space(block_group, left_info); | |
6226cb0a JB |
1411 | info->offset = left_info->offset; |
1412 | info->bytes += left_info->bytes; | |
1413 | kfree(left_info); | |
120d66ee | 1414 | merged = true; |
0f9dd46c JB |
1415 | } |
1416 | ||
120d66ee LZ |
1417 | return merged; |
1418 | } | |
1419 | ||
1420 | int btrfs_add_free_space(struct btrfs_block_group_cache *block_group, | |
1421 | u64 offset, u64 bytes) | |
1422 | { | |
1423 | struct btrfs_free_space *info; | |
1424 | int ret = 0; | |
1425 | ||
1426 | info = kzalloc(sizeof(struct btrfs_free_space), GFP_NOFS); | |
1427 | if (!info) | |
1428 | return -ENOMEM; | |
1429 | ||
1430 | info->offset = offset; | |
1431 | info->bytes = bytes; | |
1432 | ||
1433 | spin_lock(&block_group->tree_lock); | |
1434 | ||
f333adb5 | 1435 | if (try_merge_free_space(block_group, info, true)) |
120d66ee LZ |
1436 | goto link; |
1437 | ||
1438 | /* | |
1439 | * There was no extent directly to the left or right of this new | |
1440 | * extent then we know we're going to have to allocate a new extent, so | |
1441 | * before we do that see if we need to drop this into a bitmap | |
1442 | */ | |
1443 | ret = insert_into_bitmap(block_group, info); | |
1444 | if (ret < 0) { | |
1445 | goto out; | |
1446 | } else if (ret) { | |
1447 | ret = 0; | |
1448 | goto out; | |
1449 | } | |
1450 | link: | |
0f9dd46c JB |
1451 | ret = link_free_space(block_group, info); |
1452 | if (ret) | |
1453 | kfree(info); | |
96303081 | 1454 | out: |
6226cb0a JB |
1455 | spin_unlock(&block_group->tree_lock); |
1456 | ||
0f9dd46c | 1457 | if (ret) { |
96303081 | 1458 | printk(KERN_CRIT "btrfs: unable to add free space :%d\n", ret); |
c293498b | 1459 | BUG_ON(ret == -EEXIST); |
0f9dd46c JB |
1460 | } |
1461 | ||
0f9dd46c JB |
1462 | return ret; |
1463 | } | |
1464 | ||
6226cb0a JB |
1465 | int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group, |
1466 | u64 offset, u64 bytes) | |
0f9dd46c JB |
1467 | { |
1468 | struct btrfs_free_space *info; | |
96303081 | 1469 | struct btrfs_free_space *next_info = NULL; |
0f9dd46c JB |
1470 | int ret = 0; |
1471 | ||
6226cb0a JB |
1472 | spin_lock(&block_group->tree_lock); |
1473 | ||
96303081 JB |
1474 | again: |
1475 | info = tree_search_offset(block_group, offset, 0, 0); | |
1476 | if (!info) { | |
6606bb97 JB |
1477 | /* |
1478 | * oops didn't find an extent that matched the space we wanted | |
1479 | * to remove, look for a bitmap instead | |
1480 | */ | |
1481 | info = tree_search_offset(block_group, | |
1482 | offset_to_bitmap(block_group, offset), | |
1483 | 1, 0); | |
1484 | if (!info) { | |
1485 | WARN_ON(1); | |
1486 | goto out_lock; | |
1487 | } | |
96303081 JB |
1488 | } |
1489 | ||
1490 | if (info->bytes < bytes && rb_next(&info->offset_index)) { | |
1491 | u64 end; | |
1492 | next_info = rb_entry(rb_next(&info->offset_index), | |
1493 | struct btrfs_free_space, | |
1494 | offset_index); | |
1495 | ||
1496 | if (next_info->bitmap) | |
1497 | end = next_info->offset + BITS_PER_BITMAP * | |
1498 | block_group->sectorsize - 1; | |
1499 | else | |
1500 | end = next_info->offset + next_info->bytes; | |
1501 | ||
1502 | if (next_info->bytes < bytes || | |
1503 | next_info->offset > offset || offset > end) { | |
1504 | printk(KERN_CRIT "Found free space at %llu, size %llu," | |
1505 | " trying to use %llu\n", | |
1506 | (unsigned long long)info->offset, | |
1507 | (unsigned long long)info->bytes, | |
1508 | (unsigned long long)bytes); | |
0f9dd46c JB |
1509 | WARN_ON(1); |
1510 | ret = -EINVAL; | |
96303081 | 1511 | goto out_lock; |
0f9dd46c | 1512 | } |
0f9dd46c | 1513 | |
96303081 JB |
1514 | info = next_info; |
1515 | } | |
1516 | ||
1517 | if (info->bytes == bytes) { | |
1518 | unlink_free_space(block_group, info); | |
1519 | if (info->bitmap) { | |
1520 | kfree(info->bitmap); | |
1521 | block_group->total_bitmaps--; | |
0f9dd46c | 1522 | } |
96303081 JB |
1523 | kfree(info); |
1524 | goto out_lock; | |
1525 | } | |
0f9dd46c | 1526 | |
96303081 JB |
1527 | if (!info->bitmap && info->offset == offset) { |
1528 | unlink_free_space(block_group, info); | |
0f9dd46c JB |
1529 | info->offset += bytes; |
1530 | info->bytes -= bytes; | |
96303081 JB |
1531 | link_free_space(block_group, info); |
1532 | goto out_lock; | |
1533 | } | |
0f9dd46c | 1534 | |
96303081 JB |
1535 | if (!info->bitmap && info->offset <= offset && |
1536 | info->offset + info->bytes >= offset + bytes) { | |
9b49c9b9 CM |
1537 | u64 old_start = info->offset; |
1538 | /* | |
1539 | * we're freeing space in the middle of the info, | |
1540 | * this can happen during tree log replay | |
1541 | * | |
1542 | * first unlink the old info and then | |
1543 | * insert it again after the hole we're creating | |
1544 | */ | |
1545 | unlink_free_space(block_group, info); | |
1546 | if (offset + bytes < info->offset + info->bytes) { | |
1547 | u64 old_end = info->offset + info->bytes; | |
1548 | ||
1549 | info->offset = offset + bytes; | |
1550 | info->bytes = old_end - info->offset; | |
1551 | ret = link_free_space(block_group, info); | |
96303081 JB |
1552 | WARN_ON(ret); |
1553 | if (ret) | |
1554 | goto out_lock; | |
9b49c9b9 CM |
1555 | } else { |
1556 | /* the hole we're creating ends at the end | |
1557 | * of the info struct, just free the info | |
1558 | */ | |
1559 | kfree(info); | |
1560 | } | |
6226cb0a | 1561 | spin_unlock(&block_group->tree_lock); |
96303081 JB |
1562 | |
1563 | /* step two, insert a new info struct to cover | |
1564 | * anything before the hole | |
9b49c9b9 | 1565 | */ |
6226cb0a JB |
1566 | ret = btrfs_add_free_space(block_group, old_start, |
1567 | offset - old_start); | |
96303081 JB |
1568 | WARN_ON(ret); |
1569 | goto out; | |
0f9dd46c | 1570 | } |
96303081 JB |
1571 | |
1572 | ret = remove_from_bitmap(block_group, info, &offset, &bytes); | |
1573 | if (ret == -EAGAIN) | |
1574 | goto again; | |
1575 | BUG_ON(ret); | |
1576 | out_lock: | |
1577 | spin_unlock(&block_group->tree_lock); | |
0f9dd46c | 1578 | out: |
25179201 JB |
1579 | return ret; |
1580 | } | |
1581 | ||
0f9dd46c JB |
1582 | void btrfs_dump_free_space(struct btrfs_block_group_cache *block_group, |
1583 | u64 bytes) | |
1584 | { | |
1585 | struct btrfs_free_space *info; | |
1586 | struct rb_node *n; | |
1587 | int count = 0; | |
1588 | ||
1589 | for (n = rb_first(&block_group->free_space_offset); n; n = rb_next(n)) { | |
1590 | info = rb_entry(n, struct btrfs_free_space, offset_index); | |
1591 | if (info->bytes >= bytes) | |
1592 | count++; | |
96303081 | 1593 | printk(KERN_CRIT "entry offset %llu, bytes %llu, bitmap %s\n", |
21380931 | 1594 | (unsigned long long)info->offset, |
96303081 JB |
1595 | (unsigned long long)info->bytes, |
1596 | (info->bitmap) ? "yes" : "no"); | |
0f9dd46c | 1597 | } |
96303081 JB |
1598 | printk(KERN_INFO "block group has cluster?: %s\n", |
1599 | list_empty(&block_group->cluster_list) ? "no" : "yes"); | |
0f9dd46c JB |
1600 | printk(KERN_INFO "%d blocks of free space at or bigger than bytes is" |
1601 | "\n", count); | |
1602 | } | |
1603 | ||
1604 | u64 btrfs_block_group_free_space(struct btrfs_block_group_cache *block_group) | |
1605 | { | |
1606 | struct btrfs_free_space *info; | |
1607 | struct rb_node *n; | |
1608 | u64 ret = 0; | |
1609 | ||
1610 | for (n = rb_first(&block_group->free_space_offset); n; | |
1611 | n = rb_next(n)) { | |
1612 | info = rb_entry(n, struct btrfs_free_space, offset_index); | |
1613 | ret += info->bytes; | |
1614 | } | |
1615 | ||
1616 | return ret; | |
1617 | } | |
1618 | ||
fa9c0d79 CM |
1619 | /* |
1620 | * for a given cluster, put all of its extents back into the free | |
1621 | * space cache. If the block group passed doesn't match the block group | |
1622 | * pointed to by the cluster, someone else raced in and freed the | |
1623 | * cluster already. In that case, we just return without changing anything | |
1624 | */ | |
1625 | static int | |
1626 | __btrfs_return_cluster_to_free_space( | |
1627 | struct btrfs_block_group_cache *block_group, | |
1628 | struct btrfs_free_cluster *cluster) | |
1629 | { | |
1630 | struct btrfs_free_space *entry; | |
1631 | struct rb_node *node; | |
96303081 | 1632 | bool bitmap; |
fa9c0d79 CM |
1633 | |
1634 | spin_lock(&cluster->lock); | |
1635 | if (cluster->block_group != block_group) | |
1636 | goto out; | |
1637 | ||
96303081 JB |
1638 | bitmap = cluster->points_to_bitmap; |
1639 | cluster->block_group = NULL; | |
fa9c0d79 | 1640 | cluster->window_start = 0; |
96303081 JB |
1641 | list_del_init(&cluster->block_group_list); |
1642 | cluster->points_to_bitmap = false; | |
1643 | ||
1644 | if (bitmap) | |
1645 | goto out; | |
1646 | ||
fa9c0d79 | 1647 | node = rb_first(&cluster->root); |
96303081 | 1648 | while (node) { |
fa9c0d79 CM |
1649 | entry = rb_entry(node, struct btrfs_free_space, offset_index); |
1650 | node = rb_next(&entry->offset_index); | |
1651 | rb_erase(&entry->offset_index, &cluster->root); | |
96303081 | 1652 | BUG_ON(entry->bitmap); |
f333adb5 | 1653 | try_merge_free_space(block_group, entry, false); |
96303081 JB |
1654 | tree_insert_offset(&block_group->free_space_offset, |
1655 | entry->offset, &entry->offset_index, 0); | |
fa9c0d79 | 1656 | } |
6bef4d31 | 1657 | cluster->root = RB_ROOT; |
96303081 | 1658 | |
fa9c0d79 CM |
1659 | out: |
1660 | spin_unlock(&cluster->lock); | |
96303081 | 1661 | btrfs_put_block_group(block_group); |
fa9c0d79 CM |
1662 | return 0; |
1663 | } | |
1664 | ||
0f9dd46c JB |
1665 | void btrfs_remove_free_space_cache(struct btrfs_block_group_cache *block_group) |
1666 | { | |
1667 | struct btrfs_free_space *info; | |
1668 | struct rb_node *node; | |
fa9c0d79 | 1669 | struct btrfs_free_cluster *cluster; |
96303081 | 1670 | struct list_head *head; |
0f9dd46c | 1671 | |
6226cb0a | 1672 | spin_lock(&block_group->tree_lock); |
96303081 JB |
1673 | while ((head = block_group->cluster_list.next) != |
1674 | &block_group->cluster_list) { | |
1675 | cluster = list_entry(head, struct btrfs_free_cluster, | |
1676 | block_group_list); | |
fa9c0d79 CM |
1677 | |
1678 | WARN_ON(cluster->block_group != block_group); | |
1679 | __btrfs_return_cluster_to_free_space(block_group, cluster); | |
96303081 JB |
1680 | if (need_resched()) { |
1681 | spin_unlock(&block_group->tree_lock); | |
1682 | cond_resched(); | |
1683 | spin_lock(&block_group->tree_lock); | |
1684 | } | |
fa9c0d79 CM |
1685 | } |
1686 | ||
96303081 JB |
1687 | while ((node = rb_last(&block_group->free_space_offset)) != NULL) { |
1688 | info = rb_entry(node, struct btrfs_free_space, offset_index); | |
0f9dd46c | 1689 | unlink_free_space(block_group, info); |
96303081 JB |
1690 | if (info->bitmap) |
1691 | kfree(info->bitmap); | |
0f9dd46c JB |
1692 | kfree(info); |
1693 | if (need_resched()) { | |
6226cb0a | 1694 | spin_unlock(&block_group->tree_lock); |
0f9dd46c | 1695 | cond_resched(); |
6226cb0a | 1696 | spin_lock(&block_group->tree_lock); |
0f9dd46c JB |
1697 | } |
1698 | } | |
96303081 | 1699 | |
6226cb0a | 1700 | spin_unlock(&block_group->tree_lock); |
0f9dd46c JB |
1701 | } |
1702 | ||
6226cb0a JB |
1703 | u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group, |
1704 | u64 offset, u64 bytes, u64 empty_size) | |
0f9dd46c | 1705 | { |
6226cb0a | 1706 | struct btrfs_free_space *entry = NULL; |
96303081 | 1707 | u64 bytes_search = bytes + empty_size; |
6226cb0a | 1708 | u64 ret = 0; |
0f9dd46c | 1709 | |
6226cb0a | 1710 | spin_lock(&block_group->tree_lock); |
96303081 | 1711 | entry = find_free_space(block_group, &offset, &bytes_search, 0); |
6226cb0a | 1712 | if (!entry) |
96303081 JB |
1713 | goto out; |
1714 | ||
1715 | ret = offset; | |
1716 | if (entry->bitmap) { | |
817d52f8 | 1717 | bitmap_clear_bits(block_group, entry, offset, bytes); |
edf6e2d1 LZ |
1718 | if (!entry->bytes) |
1719 | free_bitmap(block_group, entry); | |
96303081 | 1720 | } else { |
6226cb0a | 1721 | unlink_free_space(block_group, entry); |
6226cb0a JB |
1722 | entry->offset += bytes; |
1723 | entry->bytes -= bytes; | |
6226cb0a JB |
1724 | if (!entry->bytes) |
1725 | kfree(entry); | |
1726 | else | |
1727 | link_free_space(block_group, entry); | |
1728 | } | |
0f9dd46c | 1729 | |
96303081 JB |
1730 | out: |
1731 | spin_unlock(&block_group->tree_lock); | |
817d52f8 | 1732 | |
0f9dd46c JB |
1733 | return ret; |
1734 | } | |
fa9c0d79 CM |
1735 | |
1736 | /* | |
1737 | * given a cluster, put all of its extents back into the free space | |
1738 | * cache. If a block group is passed, this function will only free | |
1739 | * a cluster that belongs to the passed block group. | |
1740 | * | |
1741 | * Otherwise, it'll get a reference on the block group pointed to by the | |
1742 | * cluster and remove the cluster from it. | |
1743 | */ | |
1744 | int btrfs_return_cluster_to_free_space( | |
1745 | struct btrfs_block_group_cache *block_group, | |
1746 | struct btrfs_free_cluster *cluster) | |
1747 | { | |
1748 | int ret; | |
1749 | ||
1750 | /* first, get a safe pointer to the block group */ | |
1751 | spin_lock(&cluster->lock); | |
1752 | if (!block_group) { | |
1753 | block_group = cluster->block_group; | |
1754 | if (!block_group) { | |
1755 | spin_unlock(&cluster->lock); | |
1756 | return 0; | |
1757 | } | |
1758 | } else if (cluster->block_group != block_group) { | |
1759 | /* someone else has already freed it don't redo their work */ | |
1760 | spin_unlock(&cluster->lock); | |
1761 | return 0; | |
1762 | } | |
1763 | atomic_inc(&block_group->count); | |
1764 | spin_unlock(&cluster->lock); | |
1765 | ||
1766 | /* now return any extents the cluster had on it */ | |
1767 | spin_lock(&block_group->tree_lock); | |
1768 | ret = __btrfs_return_cluster_to_free_space(block_group, cluster); | |
1769 | spin_unlock(&block_group->tree_lock); | |
1770 | ||
1771 | /* finally drop our ref */ | |
1772 | btrfs_put_block_group(block_group); | |
1773 | return ret; | |
1774 | } | |
1775 | ||
96303081 JB |
1776 | static u64 btrfs_alloc_from_bitmap(struct btrfs_block_group_cache *block_group, |
1777 | struct btrfs_free_cluster *cluster, | |
1778 | u64 bytes, u64 min_start) | |
1779 | { | |
1780 | struct btrfs_free_space *entry; | |
1781 | int err; | |
1782 | u64 search_start = cluster->window_start; | |
1783 | u64 search_bytes = bytes; | |
1784 | u64 ret = 0; | |
1785 | ||
1786 | spin_lock(&block_group->tree_lock); | |
1787 | spin_lock(&cluster->lock); | |
1788 | ||
1789 | if (!cluster->points_to_bitmap) | |
1790 | goto out; | |
1791 | ||
1792 | if (cluster->block_group != block_group) | |
1793 | goto out; | |
1794 | ||
6606bb97 JB |
1795 | /* |
1796 | * search_start is the beginning of the bitmap, but at some point it may | |
1797 | * be a good idea to point to the actual start of the free area in the | |
1798 | * bitmap, so do the offset_to_bitmap trick anyway, and set bitmap_only | |
1799 | * to 1 to make sure we get the bitmap entry | |
1800 | */ | |
1801 | entry = tree_search_offset(block_group, | |
1802 | offset_to_bitmap(block_group, search_start), | |
1803 | 1, 0); | |
96303081 JB |
1804 | if (!entry || !entry->bitmap) |
1805 | goto out; | |
1806 | ||
1807 | search_start = min_start; | |
1808 | search_bytes = bytes; | |
1809 | ||
1810 | err = search_bitmap(block_group, entry, &search_start, | |
1811 | &search_bytes); | |
1812 | if (err) | |
1813 | goto out; | |
1814 | ||
1815 | ret = search_start; | |
817d52f8 | 1816 | bitmap_clear_bits(block_group, entry, ret, bytes); |
70b7da30 LZ |
1817 | if (entry->bytes == 0) |
1818 | free_bitmap(block_group, entry); | |
96303081 JB |
1819 | out: |
1820 | spin_unlock(&cluster->lock); | |
1821 | spin_unlock(&block_group->tree_lock); | |
1822 | ||
1823 | return ret; | |
1824 | } | |
1825 | ||
fa9c0d79 CM |
1826 | /* |
1827 | * given a cluster, try to allocate 'bytes' from it, returns 0 | |
1828 | * if it couldn't find anything suitably large, or a logical disk offset | |
1829 | * if things worked out | |
1830 | */ | |
1831 | u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group, | |
1832 | struct btrfs_free_cluster *cluster, u64 bytes, | |
1833 | u64 min_start) | |
1834 | { | |
1835 | struct btrfs_free_space *entry = NULL; | |
1836 | struct rb_node *node; | |
1837 | u64 ret = 0; | |
1838 | ||
96303081 JB |
1839 | if (cluster->points_to_bitmap) |
1840 | return btrfs_alloc_from_bitmap(block_group, cluster, bytes, | |
1841 | min_start); | |
1842 | ||
fa9c0d79 CM |
1843 | spin_lock(&cluster->lock); |
1844 | if (bytes > cluster->max_size) | |
1845 | goto out; | |
1846 | ||
1847 | if (cluster->block_group != block_group) | |
1848 | goto out; | |
1849 | ||
1850 | node = rb_first(&cluster->root); | |
1851 | if (!node) | |
1852 | goto out; | |
1853 | ||
1854 | entry = rb_entry(node, struct btrfs_free_space, offset_index); | |
1855 | ||
1856 | while(1) { | |
1857 | if (entry->bytes < bytes || entry->offset < min_start) { | |
1858 | struct rb_node *node; | |
1859 | ||
1860 | node = rb_next(&entry->offset_index); | |
1861 | if (!node) | |
1862 | break; | |
1863 | entry = rb_entry(node, struct btrfs_free_space, | |
1864 | offset_index); | |
1865 | continue; | |
1866 | } | |
1867 | ret = entry->offset; | |
1868 | ||
1869 | entry->offset += bytes; | |
1870 | entry->bytes -= bytes; | |
1871 | ||
5e71b5d5 | 1872 | if (entry->bytes == 0) |
fa9c0d79 | 1873 | rb_erase(&entry->offset_index, &cluster->root); |
fa9c0d79 CM |
1874 | break; |
1875 | } | |
1876 | out: | |
1877 | spin_unlock(&cluster->lock); | |
96303081 | 1878 | |
5e71b5d5 LZ |
1879 | if (!ret) |
1880 | return 0; | |
1881 | ||
1882 | spin_lock(&block_group->tree_lock); | |
1883 | ||
1884 | block_group->free_space -= bytes; | |
1885 | if (entry->bytes == 0) { | |
1886 | block_group->free_extents--; | |
1887 | kfree(entry); | |
1888 | } | |
1889 | ||
1890 | spin_unlock(&block_group->tree_lock); | |
1891 | ||
fa9c0d79 CM |
1892 | return ret; |
1893 | } | |
1894 | ||
96303081 JB |
1895 | static int btrfs_bitmap_cluster(struct btrfs_block_group_cache *block_group, |
1896 | struct btrfs_free_space *entry, | |
1897 | struct btrfs_free_cluster *cluster, | |
1898 | u64 offset, u64 bytes, u64 min_bytes) | |
1899 | { | |
1900 | unsigned long next_zero; | |
1901 | unsigned long i; | |
1902 | unsigned long search_bits; | |
1903 | unsigned long total_bits; | |
1904 | unsigned long found_bits; | |
1905 | unsigned long start = 0; | |
1906 | unsigned long total_found = 0; | |
1907 | bool found = false; | |
1908 | ||
1909 | i = offset_to_bit(entry->offset, block_group->sectorsize, | |
1910 | max_t(u64, offset, entry->offset)); | |
1911 | search_bits = bytes_to_bits(min_bytes, block_group->sectorsize); | |
1912 | total_bits = bytes_to_bits(bytes, block_group->sectorsize); | |
1913 | ||
1914 | again: | |
1915 | found_bits = 0; | |
1916 | for (i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, i); | |
1917 | i < BITS_PER_BITMAP; | |
1918 | i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, i + 1)) { | |
1919 | next_zero = find_next_zero_bit(entry->bitmap, | |
1920 | BITS_PER_BITMAP, i); | |
1921 | if (next_zero - i >= search_bits) { | |
1922 | found_bits = next_zero - i; | |
1923 | break; | |
1924 | } | |
1925 | i = next_zero; | |
1926 | } | |
1927 | ||
1928 | if (!found_bits) | |
1929 | return -1; | |
1930 | ||
1931 | if (!found) { | |
1932 | start = i; | |
1933 | found = true; | |
1934 | } | |
1935 | ||
1936 | total_found += found_bits; | |
1937 | ||
1938 | if (cluster->max_size < found_bits * block_group->sectorsize) | |
1939 | cluster->max_size = found_bits * block_group->sectorsize; | |
1940 | ||
1941 | if (total_found < total_bits) { | |
1942 | i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, next_zero); | |
1943 | if (i - start > total_bits * 2) { | |
1944 | total_found = 0; | |
1945 | cluster->max_size = 0; | |
1946 | found = false; | |
1947 | } | |
1948 | goto again; | |
1949 | } | |
1950 | ||
1951 | cluster->window_start = start * block_group->sectorsize + | |
1952 | entry->offset; | |
1953 | cluster->points_to_bitmap = true; | |
1954 | ||
1955 | return 0; | |
1956 | } | |
1957 | ||
fa9c0d79 CM |
1958 | /* |
1959 | * here we try to find a cluster of blocks in a block group. The goal | |
1960 | * is to find at least bytes free and up to empty_size + bytes free. | |
1961 | * We might not find them all in one contiguous area. | |
1962 | * | |
1963 | * returns zero and sets up cluster if things worked out, otherwise | |
1964 | * it returns -enospc | |
1965 | */ | |
1966 | int btrfs_find_space_cluster(struct btrfs_trans_handle *trans, | |
451d7585 | 1967 | struct btrfs_root *root, |
fa9c0d79 CM |
1968 | struct btrfs_block_group_cache *block_group, |
1969 | struct btrfs_free_cluster *cluster, | |
1970 | u64 offset, u64 bytes, u64 empty_size) | |
1971 | { | |
1972 | struct btrfs_free_space *entry = NULL; | |
1973 | struct rb_node *node; | |
1974 | struct btrfs_free_space *next; | |
96303081 | 1975 | struct btrfs_free_space *last = NULL; |
fa9c0d79 CM |
1976 | u64 min_bytes; |
1977 | u64 window_start; | |
1978 | u64 window_free; | |
1979 | u64 max_extent = 0; | |
96303081 | 1980 | bool found_bitmap = false; |
fa9c0d79 CM |
1981 | int ret; |
1982 | ||
1983 | /* for metadata, allow allocates with more holes */ | |
451d7585 CM |
1984 | if (btrfs_test_opt(root, SSD_SPREAD)) { |
1985 | min_bytes = bytes + empty_size; | |
1986 | } else if (block_group->flags & BTRFS_BLOCK_GROUP_METADATA) { | |
fa9c0d79 CM |
1987 | /* |
1988 | * we want to do larger allocations when we are | |
1989 | * flushing out the delayed refs, it helps prevent | |
1990 | * making more work as we go along. | |
1991 | */ | |
1992 | if (trans->transaction->delayed_refs.flushing) | |
1993 | min_bytes = max(bytes, (bytes + empty_size) >> 1); | |
1994 | else | |
1995 | min_bytes = max(bytes, (bytes + empty_size) >> 4); | |
1996 | } else | |
1997 | min_bytes = max(bytes, (bytes + empty_size) >> 2); | |
1998 | ||
1999 | spin_lock(&block_group->tree_lock); | |
2000 | spin_lock(&cluster->lock); | |
2001 | ||
2002 | /* someone already found a cluster, hooray */ | |
2003 | if (cluster->block_group) { | |
2004 | ret = 0; | |
2005 | goto out; | |
2006 | } | |
2007 | again: | |
96303081 | 2008 | entry = tree_search_offset(block_group, offset, found_bitmap, 1); |
fa9c0d79 CM |
2009 | if (!entry) { |
2010 | ret = -ENOSPC; | |
2011 | goto out; | |
2012 | } | |
96303081 JB |
2013 | |
2014 | /* | |
2015 | * If found_bitmap is true, we exhausted our search for extent entries, | |
2016 | * and we just want to search all of the bitmaps that we can find, and | |
2017 | * ignore any extent entries we find. | |
2018 | */ | |
2019 | while (entry->bitmap || found_bitmap || | |
2020 | (!entry->bitmap && entry->bytes < min_bytes)) { | |
2021 | struct rb_node *node = rb_next(&entry->offset_index); | |
2022 | ||
2023 | if (entry->bitmap && entry->bytes > bytes + empty_size) { | |
2024 | ret = btrfs_bitmap_cluster(block_group, entry, cluster, | |
2025 | offset, bytes + empty_size, | |
2026 | min_bytes); | |
2027 | if (!ret) | |
2028 | goto got_it; | |
2029 | } | |
2030 | ||
2031 | if (!node) { | |
2032 | ret = -ENOSPC; | |
2033 | goto out; | |
2034 | } | |
2035 | entry = rb_entry(node, struct btrfs_free_space, offset_index); | |
2036 | } | |
2037 | ||
2038 | /* | |
2039 | * We already searched all the extent entries from the passed in offset | |
2040 | * to the end and didn't find enough space for the cluster, and we also | |
2041 | * didn't find any bitmaps that met our criteria, just go ahead and exit | |
2042 | */ | |
2043 | if (found_bitmap) { | |
2044 | ret = -ENOSPC; | |
2045 | goto out; | |
2046 | } | |
2047 | ||
2048 | cluster->points_to_bitmap = false; | |
fa9c0d79 CM |
2049 | window_start = entry->offset; |
2050 | window_free = entry->bytes; | |
2051 | last = entry; | |
2052 | max_extent = entry->bytes; | |
2053 | ||
96303081 | 2054 | while (1) { |
fa9c0d79 CM |
2055 | /* out window is just right, lets fill it */ |
2056 | if (window_free >= bytes + empty_size) | |
2057 | break; | |
2058 | ||
2059 | node = rb_next(&last->offset_index); | |
2060 | if (!node) { | |
96303081 JB |
2061 | if (found_bitmap) |
2062 | goto again; | |
fa9c0d79 CM |
2063 | ret = -ENOSPC; |
2064 | goto out; | |
2065 | } | |
2066 | next = rb_entry(node, struct btrfs_free_space, offset_index); | |
2067 | ||
96303081 JB |
2068 | /* |
2069 | * we found a bitmap, so if this search doesn't result in a | |
2070 | * cluster, we know to go and search again for the bitmaps and | |
2071 | * start looking for space there | |
2072 | */ | |
2073 | if (next->bitmap) { | |
2074 | if (!found_bitmap) | |
2075 | offset = next->offset; | |
2076 | found_bitmap = true; | |
2077 | last = next; | |
2078 | continue; | |
2079 | } | |
2080 | ||
fa9c0d79 CM |
2081 | /* |
2082 | * we haven't filled the empty size and the window is | |
2083 | * very large. reset and try again | |
2084 | */ | |
c6044801 CM |
2085 | if (next->offset - (last->offset + last->bytes) > 128 * 1024 || |
2086 | next->offset - window_start > (bytes + empty_size) * 2) { | |
fa9c0d79 CM |
2087 | entry = next; |
2088 | window_start = entry->offset; | |
2089 | window_free = entry->bytes; | |
2090 | last = entry; | |
01dea1ef | 2091 | max_extent = entry->bytes; |
fa9c0d79 CM |
2092 | } else { |
2093 | last = next; | |
2094 | window_free += next->bytes; | |
2095 | if (entry->bytes > max_extent) | |
2096 | max_extent = entry->bytes; | |
2097 | } | |
2098 | } | |
2099 | ||
2100 | cluster->window_start = entry->offset; | |
2101 | ||
2102 | /* | |
2103 | * now we've found our entries, pull them out of the free space | |
2104 | * cache and put them into the cluster rbtree | |
2105 | * | |
2106 | * The cluster includes an rbtree, but only uses the offset index | |
2107 | * of each free space cache entry. | |
2108 | */ | |
96303081 | 2109 | while (1) { |
fa9c0d79 | 2110 | node = rb_next(&entry->offset_index); |
96303081 JB |
2111 | if (entry->bitmap && node) { |
2112 | entry = rb_entry(node, struct btrfs_free_space, | |
2113 | offset_index); | |
2114 | continue; | |
2115 | } else if (entry->bitmap && !node) { | |
2116 | break; | |
2117 | } | |
2118 | ||
2119 | rb_erase(&entry->offset_index, &block_group->free_space_offset); | |
fa9c0d79 | 2120 | ret = tree_insert_offset(&cluster->root, entry->offset, |
96303081 | 2121 | &entry->offset_index, 0); |
fa9c0d79 CM |
2122 | BUG_ON(ret); |
2123 | ||
2124 | if (!node || entry == last) | |
2125 | break; | |
2126 | ||
2127 | entry = rb_entry(node, struct btrfs_free_space, offset_index); | |
2128 | } | |
96303081 | 2129 | |
fa9c0d79 | 2130 | cluster->max_size = max_extent; |
96303081 JB |
2131 | got_it: |
2132 | ret = 0; | |
fa9c0d79 CM |
2133 | atomic_inc(&block_group->count); |
2134 | list_add_tail(&cluster->block_group_list, &block_group->cluster_list); | |
2135 | cluster->block_group = block_group; | |
2136 | out: | |
2137 | spin_unlock(&cluster->lock); | |
2138 | spin_unlock(&block_group->tree_lock); | |
2139 | ||
2140 | return ret; | |
2141 | } | |
2142 | ||
2143 | /* | |
2144 | * simple code to zero out a cluster | |
2145 | */ | |
2146 | void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster) | |
2147 | { | |
2148 | spin_lock_init(&cluster->lock); | |
2149 | spin_lock_init(&cluster->refill_lock); | |
6bef4d31 | 2150 | cluster->root = RB_ROOT; |
fa9c0d79 | 2151 | cluster->max_size = 0; |
96303081 | 2152 | cluster->points_to_bitmap = false; |
fa9c0d79 CM |
2153 | INIT_LIST_HEAD(&cluster->block_group_list); |
2154 | cluster->block_group = NULL; | |
2155 | } | |
2156 |