Commit | Line | Data |
---|---|---|
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 | ||
0cb59c99 JB |
190 | int btrfs_write_out_cache(struct btrfs_root *root, |
191 | struct btrfs_trans_handle *trans, | |
192 | struct btrfs_block_group_cache *block_group, | |
193 | struct btrfs_path *path) | |
194 | { | |
195 | struct btrfs_free_space_header *header; | |
196 | struct extent_buffer *leaf; | |
197 | struct inode *inode; | |
198 | struct rb_node *node; | |
199 | struct list_head *pos, *n; | |
200 | struct page *page; | |
201 | struct extent_state *cached_state = NULL; | |
202 | struct list_head bitmap_list; | |
203 | struct btrfs_key key; | |
204 | u64 bytes = 0; | |
205 | u32 *crc, *checksums; | |
206 | pgoff_t index = 0, last_index = 0; | |
207 | unsigned long first_page_offset; | |
208 | int num_checksums; | |
209 | int entries = 0; | |
210 | int bitmaps = 0; | |
211 | int ret = 0; | |
212 | ||
213 | root = root->fs_info->tree_root; | |
214 | ||
215 | INIT_LIST_HEAD(&bitmap_list); | |
216 | ||
217 | spin_lock(&block_group->lock); | |
218 | if (block_group->disk_cache_state < BTRFS_DC_SETUP) { | |
219 | spin_unlock(&block_group->lock); | |
220 | return 0; | |
221 | } | |
222 | spin_unlock(&block_group->lock); | |
223 | ||
224 | inode = lookup_free_space_inode(root, block_group, path); | |
225 | if (IS_ERR(inode)) | |
226 | return 0; | |
227 | ||
228 | if (!i_size_read(inode)) { | |
229 | iput(inode); | |
230 | return 0; | |
231 | } | |
232 | ||
233 | last_index = (i_size_read(inode) - 1) >> PAGE_CACHE_SHIFT; | |
234 | filemap_write_and_wait(inode->i_mapping); | |
235 | btrfs_wait_ordered_range(inode, inode->i_size & | |
236 | ~(root->sectorsize - 1), (u64)-1); | |
237 | ||
238 | /* We need a checksum per page. */ | |
239 | num_checksums = i_size_read(inode) / PAGE_CACHE_SIZE; | |
240 | crc = checksums = kzalloc(sizeof(u32) * num_checksums, GFP_NOFS); | |
241 | if (!crc) { | |
242 | iput(inode); | |
243 | return 0; | |
244 | } | |
245 | ||
246 | /* Since the first page has all of our checksums and our generation we | |
247 | * need to calculate the offset into the page that we can start writing | |
248 | * our entries. | |
249 | */ | |
250 | first_page_offset = (sizeof(u32) * num_checksums) + sizeof(u64); | |
251 | ||
252 | node = rb_first(&block_group->free_space_offset); | |
253 | if (!node) | |
254 | goto out_free; | |
255 | ||
256 | /* | |
257 | * Lock all pages first so we can lock the extent safely. | |
258 | * | |
259 | * NOTE: Because we hold the ref the entire time we're going to write to | |
260 | * the page find_get_page should never fail, so we don't do a check | |
261 | * after find_get_page at this point. Just putting this here so people | |
262 | * know and don't freak out. | |
263 | */ | |
264 | while (index <= last_index) { | |
265 | page = grab_cache_page(inode->i_mapping, index); | |
266 | if (!page) { | |
267 | pgoff_t i = 0; | |
268 | ||
269 | while (i < index) { | |
270 | page = find_get_page(inode->i_mapping, i); | |
271 | unlock_page(page); | |
272 | page_cache_release(page); | |
273 | page_cache_release(page); | |
274 | i++; | |
275 | } | |
276 | goto out_free; | |
277 | } | |
278 | index++; | |
279 | } | |
280 | ||
281 | index = 0; | |
282 | lock_extent_bits(&BTRFS_I(inode)->io_tree, 0, i_size_read(inode) - 1, | |
283 | 0, &cached_state, GFP_NOFS); | |
284 | ||
285 | /* Write out the extent entries */ | |
286 | do { | |
287 | struct btrfs_free_space_entry *entry; | |
288 | void *addr; | |
289 | unsigned long offset = 0; | |
290 | unsigned long start_offset = 0; | |
291 | ||
292 | if (index == 0) { | |
293 | start_offset = first_page_offset; | |
294 | offset = start_offset; | |
295 | } | |
296 | ||
297 | page = find_get_page(inode->i_mapping, index); | |
298 | ||
299 | addr = kmap(page); | |
300 | entry = addr + start_offset; | |
301 | ||
302 | memset(addr, 0, PAGE_CACHE_SIZE); | |
303 | while (1) { | |
304 | struct btrfs_free_space *e; | |
305 | ||
306 | e = rb_entry(node, struct btrfs_free_space, offset_index); | |
307 | entries++; | |
308 | ||
309 | entry->offset = cpu_to_le64(e->offset); | |
310 | entry->bytes = cpu_to_le64(e->bytes); | |
311 | if (e->bitmap) { | |
312 | entry->type = BTRFS_FREE_SPACE_BITMAP; | |
313 | list_add_tail(&e->list, &bitmap_list); | |
314 | bitmaps++; | |
315 | } else { | |
316 | entry->type = BTRFS_FREE_SPACE_EXTENT; | |
317 | } | |
318 | node = rb_next(node); | |
319 | if (!node) | |
320 | break; | |
321 | offset += sizeof(struct btrfs_free_space_entry); | |
322 | if (offset + sizeof(struct btrfs_free_space_entry) >= | |
323 | PAGE_CACHE_SIZE) | |
324 | break; | |
325 | entry++; | |
326 | } | |
327 | *crc = ~(u32)0; | |
328 | *crc = btrfs_csum_data(root, addr + start_offset, *crc, | |
329 | PAGE_CACHE_SIZE - start_offset); | |
330 | kunmap(page); | |
331 | ||
332 | btrfs_csum_final(*crc, (char *)crc); | |
333 | crc++; | |
334 | ||
335 | bytes += PAGE_CACHE_SIZE; | |
336 | ||
337 | ClearPageChecked(page); | |
338 | set_page_extent_mapped(page); | |
339 | SetPageUptodate(page); | |
340 | set_page_dirty(page); | |
341 | ||
342 | /* | |
343 | * We need to release our reference we got for grab_cache_page, | |
344 | * except for the first page which will hold our checksums, we | |
345 | * do that below. | |
346 | */ | |
347 | if (index != 0) { | |
348 | unlock_page(page); | |
349 | page_cache_release(page); | |
350 | } | |
351 | ||
352 | page_cache_release(page); | |
353 | ||
354 | index++; | |
355 | } while (node); | |
356 | ||
357 | /* Write out the bitmaps */ | |
358 | list_for_each_safe(pos, n, &bitmap_list) { | |
359 | void *addr; | |
360 | struct btrfs_free_space *entry = | |
361 | list_entry(pos, struct btrfs_free_space, list); | |
362 | ||
363 | page = find_get_page(inode->i_mapping, index); | |
364 | ||
365 | addr = kmap(page); | |
366 | memcpy(addr, entry->bitmap, PAGE_CACHE_SIZE); | |
367 | *crc = ~(u32)0; | |
368 | *crc = btrfs_csum_data(root, addr, *crc, PAGE_CACHE_SIZE); | |
369 | kunmap(page); | |
370 | btrfs_csum_final(*crc, (char *)crc); | |
371 | crc++; | |
372 | bytes += PAGE_CACHE_SIZE; | |
373 | ||
374 | ClearPageChecked(page); | |
375 | set_page_extent_mapped(page); | |
376 | SetPageUptodate(page); | |
377 | set_page_dirty(page); | |
378 | unlock_page(page); | |
379 | page_cache_release(page); | |
380 | page_cache_release(page); | |
381 | list_del_init(&entry->list); | |
382 | index++; | |
383 | } | |
384 | ||
385 | /* Zero out the rest of the pages just to make sure */ | |
386 | while (index <= last_index) { | |
387 | void *addr; | |
388 | ||
389 | page = find_get_page(inode->i_mapping, index); | |
390 | ||
391 | addr = kmap(page); | |
392 | memset(addr, 0, PAGE_CACHE_SIZE); | |
393 | kunmap(page); | |
394 | ClearPageChecked(page); | |
395 | set_page_extent_mapped(page); | |
396 | SetPageUptodate(page); | |
397 | set_page_dirty(page); | |
398 | unlock_page(page); | |
399 | page_cache_release(page); | |
400 | page_cache_release(page); | |
401 | bytes += PAGE_CACHE_SIZE; | |
402 | index++; | |
403 | } | |
404 | ||
405 | btrfs_set_extent_delalloc(inode, 0, bytes - 1, &cached_state); | |
406 | ||
407 | /* Write the checksums and trans id to the first page */ | |
408 | { | |
409 | void *addr; | |
410 | u64 *gen; | |
411 | ||
412 | page = find_get_page(inode->i_mapping, 0); | |
413 | ||
414 | addr = kmap(page); | |
415 | memcpy(addr, checksums, sizeof(u32) * num_checksums); | |
416 | gen = addr + (sizeof(u32) * num_checksums); | |
417 | *gen = trans->transid; | |
418 | kunmap(page); | |
419 | ClearPageChecked(page); | |
420 | set_page_extent_mapped(page); | |
421 | SetPageUptodate(page); | |
422 | set_page_dirty(page); | |
423 | unlock_page(page); | |
424 | page_cache_release(page); | |
425 | page_cache_release(page); | |
426 | } | |
427 | BTRFS_I(inode)->generation = trans->transid; | |
428 | ||
429 | unlock_extent_cached(&BTRFS_I(inode)->io_tree, 0, | |
430 | i_size_read(inode) - 1, &cached_state, GFP_NOFS); | |
431 | ||
432 | filemap_write_and_wait(inode->i_mapping); | |
433 | ||
434 | key.objectid = BTRFS_FREE_SPACE_OBJECTID; | |
435 | key.offset = block_group->key.objectid; | |
436 | key.type = 0; | |
437 | ||
438 | ret = btrfs_search_slot(trans, root, &key, path, 1, 1); | |
439 | if (ret < 0) { | |
440 | ret = 0; | |
441 | clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, bytes - 1, | |
442 | EXTENT_DIRTY | EXTENT_DELALLOC | | |
443 | EXTENT_DO_ACCOUNTING, 0, 0, NULL, GFP_NOFS); | |
444 | goto out_free; | |
445 | } | |
446 | leaf = path->nodes[0]; | |
447 | if (ret > 0) { | |
448 | struct btrfs_key found_key; | |
449 | BUG_ON(!path->slots[0]); | |
450 | path->slots[0]--; | |
451 | btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]); | |
452 | if (found_key.objectid != BTRFS_FREE_SPACE_OBJECTID || | |
453 | found_key.offset != block_group->key.objectid) { | |
454 | ret = 0; | |
455 | clear_extent_bit(&BTRFS_I(inode)->io_tree, 0, bytes - 1, | |
456 | EXTENT_DIRTY | EXTENT_DELALLOC | | |
457 | EXTENT_DO_ACCOUNTING, 0, 0, NULL, | |
458 | GFP_NOFS); | |
459 | btrfs_release_path(root, path); | |
460 | goto out_free; | |
461 | } | |
462 | } | |
463 | header = btrfs_item_ptr(leaf, path->slots[0], | |
464 | struct btrfs_free_space_header); | |
465 | btrfs_set_free_space_entries(leaf, header, entries); | |
466 | btrfs_set_free_space_bitmaps(leaf, header, bitmaps); | |
467 | btrfs_set_free_space_generation(leaf, header, trans->transid); | |
468 | btrfs_mark_buffer_dirty(leaf); | |
469 | btrfs_release_path(root, path); | |
470 | ||
471 | ret = 1; | |
472 | ||
473 | out_free: | |
474 | if (ret == 0) { | |
475 | invalidate_inode_pages2_range(inode->i_mapping, 0, index); | |
476 | spin_lock(&block_group->lock); | |
477 | block_group->disk_cache_state = BTRFS_DC_ERROR; | |
478 | spin_unlock(&block_group->lock); | |
479 | BTRFS_I(inode)->generation = 0; | |
480 | } | |
481 | kfree(checksums); | |
482 | btrfs_update_inode(trans, root, inode); | |
483 | iput(inode); | |
484 | return ret; | |
485 | } | |
486 | ||
96303081 JB |
487 | static inline unsigned long offset_to_bit(u64 bitmap_start, u64 sectorsize, |
488 | u64 offset) | |
0f9dd46c | 489 | { |
96303081 JB |
490 | BUG_ON(offset < bitmap_start); |
491 | offset -= bitmap_start; | |
492 | return (unsigned long)(div64_u64(offset, sectorsize)); | |
493 | } | |
0f9dd46c | 494 | |
96303081 JB |
495 | static inline unsigned long bytes_to_bits(u64 bytes, u64 sectorsize) |
496 | { | |
497 | return (unsigned long)(div64_u64(bytes, sectorsize)); | |
498 | } | |
0f9dd46c | 499 | |
96303081 JB |
500 | static inline u64 offset_to_bitmap(struct btrfs_block_group_cache *block_group, |
501 | u64 offset) | |
502 | { | |
503 | u64 bitmap_start; | |
504 | u64 bytes_per_bitmap; | |
0f9dd46c | 505 | |
96303081 JB |
506 | bytes_per_bitmap = BITS_PER_BITMAP * block_group->sectorsize; |
507 | bitmap_start = offset - block_group->key.objectid; | |
508 | bitmap_start = div64_u64(bitmap_start, bytes_per_bitmap); | |
509 | bitmap_start *= bytes_per_bitmap; | |
510 | bitmap_start += block_group->key.objectid; | |
0f9dd46c | 511 | |
96303081 | 512 | return bitmap_start; |
0f9dd46c JB |
513 | } |
514 | ||
96303081 JB |
515 | static int tree_insert_offset(struct rb_root *root, u64 offset, |
516 | struct rb_node *node, int bitmap) | |
0f9dd46c JB |
517 | { |
518 | struct rb_node **p = &root->rb_node; | |
519 | struct rb_node *parent = NULL; | |
520 | struct btrfs_free_space *info; | |
521 | ||
522 | while (*p) { | |
523 | parent = *p; | |
96303081 | 524 | info = rb_entry(parent, struct btrfs_free_space, offset_index); |
0f9dd46c | 525 | |
96303081 | 526 | if (offset < info->offset) { |
0f9dd46c | 527 | p = &(*p)->rb_left; |
96303081 | 528 | } else if (offset > info->offset) { |
0f9dd46c | 529 | p = &(*p)->rb_right; |
96303081 JB |
530 | } else { |
531 | /* | |
532 | * we could have a bitmap entry and an extent entry | |
533 | * share the same offset. If this is the case, we want | |
534 | * the extent entry to always be found first if we do a | |
535 | * linear search through the tree, since we want to have | |
536 | * the quickest allocation time, and allocating from an | |
537 | * extent is faster than allocating from a bitmap. So | |
538 | * if we're inserting a bitmap and we find an entry at | |
539 | * this offset, we want to go right, or after this entry | |
540 | * logically. If we are inserting an extent and we've | |
541 | * found a bitmap, we want to go left, or before | |
542 | * logically. | |
543 | */ | |
544 | if (bitmap) { | |
545 | WARN_ON(info->bitmap); | |
546 | p = &(*p)->rb_right; | |
547 | } else { | |
548 | WARN_ON(!info->bitmap); | |
549 | p = &(*p)->rb_left; | |
550 | } | |
551 | } | |
0f9dd46c JB |
552 | } |
553 | ||
554 | rb_link_node(node, parent, p); | |
555 | rb_insert_color(node, root); | |
556 | ||
557 | return 0; | |
558 | } | |
559 | ||
560 | /* | |
70cb0743 JB |
561 | * searches the tree for the given offset. |
562 | * | |
96303081 JB |
563 | * fuzzy - If this is set, then we are trying to make an allocation, and we just |
564 | * want a section that has at least bytes size and comes at or after the given | |
565 | * offset. | |
0f9dd46c | 566 | */ |
96303081 JB |
567 | static struct btrfs_free_space * |
568 | tree_search_offset(struct btrfs_block_group_cache *block_group, | |
569 | u64 offset, int bitmap_only, int fuzzy) | |
0f9dd46c | 570 | { |
96303081 JB |
571 | struct rb_node *n = block_group->free_space_offset.rb_node; |
572 | struct btrfs_free_space *entry, *prev = NULL; | |
573 | ||
574 | /* find entry that is closest to the 'offset' */ | |
575 | while (1) { | |
576 | if (!n) { | |
577 | entry = NULL; | |
578 | break; | |
579 | } | |
0f9dd46c | 580 | |
0f9dd46c | 581 | entry = rb_entry(n, struct btrfs_free_space, offset_index); |
96303081 | 582 | prev = entry; |
0f9dd46c | 583 | |
96303081 | 584 | if (offset < entry->offset) |
0f9dd46c | 585 | n = n->rb_left; |
96303081 | 586 | else if (offset > entry->offset) |
0f9dd46c | 587 | n = n->rb_right; |
96303081 | 588 | else |
0f9dd46c | 589 | break; |
0f9dd46c JB |
590 | } |
591 | ||
96303081 JB |
592 | if (bitmap_only) { |
593 | if (!entry) | |
594 | return NULL; | |
595 | if (entry->bitmap) | |
596 | return entry; | |
0f9dd46c | 597 | |
96303081 JB |
598 | /* |
599 | * bitmap entry and extent entry may share same offset, | |
600 | * in that case, bitmap entry comes after extent entry. | |
601 | */ | |
602 | n = rb_next(n); | |
603 | if (!n) | |
604 | return NULL; | |
605 | entry = rb_entry(n, struct btrfs_free_space, offset_index); | |
606 | if (entry->offset != offset) | |
607 | return NULL; | |
0f9dd46c | 608 | |
96303081 JB |
609 | WARN_ON(!entry->bitmap); |
610 | return entry; | |
611 | } else if (entry) { | |
612 | if (entry->bitmap) { | |
0f9dd46c | 613 | /* |
96303081 JB |
614 | * if previous extent entry covers the offset, |
615 | * we should return it instead of the bitmap entry | |
0f9dd46c | 616 | */ |
96303081 JB |
617 | n = &entry->offset_index; |
618 | while (1) { | |
619 | n = rb_prev(n); | |
620 | if (!n) | |
621 | break; | |
622 | prev = rb_entry(n, struct btrfs_free_space, | |
623 | offset_index); | |
624 | if (!prev->bitmap) { | |
625 | if (prev->offset + prev->bytes > offset) | |
626 | entry = prev; | |
627 | break; | |
628 | } | |
0f9dd46c | 629 | } |
96303081 JB |
630 | } |
631 | return entry; | |
632 | } | |
633 | ||
634 | if (!prev) | |
635 | return NULL; | |
636 | ||
637 | /* find last entry before the 'offset' */ | |
638 | entry = prev; | |
639 | if (entry->offset > offset) { | |
640 | n = rb_prev(&entry->offset_index); | |
641 | if (n) { | |
642 | entry = rb_entry(n, struct btrfs_free_space, | |
643 | offset_index); | |
644 | BUG_ON(entry->offset > offset); | |
0f9dd46c | 645 | } else { |
96303081 JB |
646 | if (fuzzy) |
647 | return entry; | |
648 | else | |
649 | return NULL; | |
0f9dd46c JB |
650 | } |
651 | } | |
652 | ||
96303081 JB |
653 | if (entry->bitmap) { |
654 | n = &entry->offset_index; | |
655 | while (1) { | |
656 | n = rb_prev(n); | |
657 | if (!n) | |
658 | break; | |
659 | prev = rb_entry(n, struct btrfs_free_space, | |
660 | offset_index); | |
661 | if (!prev->bitmap) { | |
662 | if (prev->offset + prev->bytes > offset) | |
663 | return prev; | |
664 | break; | |
665 | } | |
666 | } | |
667 | if (entry->offset + BITS_PER_BITMAP * | |
668 | block_group->sectorsize > offset) | |
669 | return entry; | |
670 | } else if (entry->offset + entry->bytes > offset) | |
671 | return entry; | |
672 | ||
673 | if (!fuzzy) | |
674 | return NULL; | |
675 | ||
676 | while (1) { | |
677 | if (entry->bitmap) { | |
678 | if (entry->offset + BITS_PER_BITMAP * | |
679 | block_group->sectorsize > offset) | |
680 | break; | |
681 | } else { | |
682 | if (entry->offset + entry->bytes > offset) | |
683 | break; | |
684 | } | |
685 | ||
686 | n = rb_next(&entry->offset_index); | |
687 | if (!n) | |
688 | return NULL; | |
689 | entry = rb_entry(n, struct btrfs_free_space, offset_index); | |
690 | } | |
691 | return entry; | |
0f9dd46c JB |
692 | } |
693 | ||
694 | static void unlink_free_space(struct btrfs_block_group_cache *block_group, | |
695 | struct btrfs_free_space *info) | |
696 | { | |
697 | rb_erase(&info->offset_index, &block_group->free_space_offset); | |
96303081 | 698 | block_group->free_extents--; |
817d52f8 | 699 | block_group->free_space -= info->bytes; |
0f9dd46c JB |
700 | } |
701 | ||
702 | static int link_free_space(struct btrfs_block_group_cache *block_group, | |
703 | struct btrfs_free_space *info) | |
704 | { | |
705 | int ret = 0; | |
706 | ||
96303081 | 707 | BUG_ON(!info->bitmap && !info->bytes); |
0f9dd46c | 708 | ret = tree_insert_offset(&block_group->free_space_offset, info->offset, |
96303081 | 709 | &info->offset_index, (info->bitmap != NULL)); |
0f9dd46c JB |
710 | if (ret) |
711 | return ret; | |
712 | ||
817d52f8 | 713 | block_group->free_space += info->bytes; |
96303081 JB |
714 | block_group->free_extents++; |
715 | return ret; | |
716 | } | |
717 | ||
718 | static void recalculate_thresholds(struct btrfs_block_group_cache *block_group) | |
719 | { | |
25891f79 JB |
720 | u64 max_bytes; |
721 | u64 bitmap_bytes; | |
722 | u64 extent_bytes; | |
96303081 JB |
723 | |
724 | /* | |
725 | * The goal is to keep the total amount of memory used per 1gb of space | |
726 | * at or below 32k, so we need to adjust how much memory we allow to be | |
727 | * used by extent based free space tracking | |
728 | */ | |
729 | max_bytes = MAX_CACHE_BYTES_PER_GIG * | |
730 | (div64_u64(block_group->key.offset, 1024 * 1024 * 1024)); | |
731 | ||
25891f79 JB |
732 | /* |
733 | * we want to account for 1 more bitmap than what we have so we can make | |
734 | * sure we don't go over our overall goal of MAX_CACHE_BYTES_PER_GIG as | |
735 | * we add more bitmaps. | |
736 | */ | |
737 | bitmap_bytes = (block_group->total_bitmaps + 1) * PAGE_CACHE_SIZE; | |
96303081 | 738 | |
25891f79 JB |
739 | if (bitmap_bytes >= max_bytes) { |
740 | block_group->extents_thresh = 0; | |
741 | return; | |
742 | } | |
96303081 | 743 | |
25891f79 JB |
744 | /* |
745 | * we want the extent entry threshold to always be at most 1/2 the maxw | |
746 | * bytes we can have, or whatever is less than that. | |
747 | */ | |
748 | extent_bytes = max_bytes - bitmap_bytes; | |
749 | extent_bytes = min_t(u64, extent_bytes, div64_u64(max_bytes, 2)); | |
96303081 | 750 | |
25891f79 JB |
751 | block_group->extents_thresh = |
752 | div64_u64(extent_bytes, (sizeof(struct btrfs_free_space))); | |
96303081 JB |
753 | } |
754 | ||
817d52f8 JB |
755 | static void bitmap_clear_bits(struct btrfs_block_group_cache *block_group, |
756 | struct btrfs_free_space *info, u64 offset, | |
757 | u64 bytes) | |
96303081 JB |
758 | { |
759 | unsigned long start, end; | |
760 | unsigned long i; | |
761 | ||
817d52f8 JB |
762 | start = offset_to_bit(info->offset, block_group->sectorsize, offset); |
763 | end = start + bytes_to_bits(bytes, block_group->sectorsize); | |
96303081 JB |
764 | BUG_ON(end > BITS_PER_BITMAP); |
765 | ||
766 | for (i = start; i < end; i++) | |
767 | clear_bit(i, info->bitmap); | |
768 | ||
769 | info->bytes -= bytes; | |
817d52f8 | 770 | block_group->free_space -= bytes; |
96303081 JB |
771 | } |
772 | ||
817d52f8 JB |
773 | static void bitmap_set_bits(struct btrfs_block_group_cache *block_group, |
774 | struct btrfs_free_space *info, u64 offset, | |
775 | u64 bytes) | |
96303081 JB |
776 | { |
777 | unsigned long start, end; | |
778 | unsigned long i; | |
779 | ||
817d52f8 JB |
780 | start = offset_to_bit(info->offset, block_group->sectorsize, offset); |
781 | end = start + bytes_to_bits(bytes, block_group->sectorsize); | |
96303081 JB |
782 | BUG_ON(end > BITS_PER_BITMAP); |
783 | ||
784 | for (i = start; i < end; i++) | |
785 | set_bit(i, info->bitmap); | |
786 | ||
787 | info->bytes += bytes; | |
817d52f8 | 788 | block_group->free_space += bytes; |
96303081 JB |
789 | } |
790 | ||
791 | static int search_bitmap(struct btrfs_block_group_cache *block_group, | |
792 | struct btrfs_free_space *bitmap_info, u64 *offset, | |
793 | u64 *bytes) | |
794 | { | |
795 | unsigned long found_bits = 0; | |
796 | unsigned long bits, i; | |
797 | unsigned long next_zero; | |
798 | ||
799 | i = offset_to_bit(bitmap_info->offset, block_group->sectorsize, | |
800 | max_t(u64, *offset, bitmap_info->offset)); | |
801 | bits = bytes_to_bits(*bytes, block_group->sectorsize); | |
802 | ||
803 | for (i = find_next_bit(bitmap_info->bitmap, BITS_PER_BITMAP, i); | |
804 | i < BITS_PER_BITMAP; | |
805 | i = find_next_bit(bitmap_info->bitmap, BITS_PER_BITMAP, i + 1)) { | |
806 | next_zero = find_next_zero_bit(bitmap_info->bitmap, | |
807 | BITS_PER_BITMAP, i); | |
808 | if ((next_zero - i) >= bits) { | |
809 | found_bits = next_zero - i; | |
810 | break; | |
811 | } | |
812 | i = next_zero; | |
813 | } | |
814 | ||
815 | if (found_bits) { | |
816 | *offset = (u64)(i * block_group->sectorsize) + | |
817 | bitmap_info->offset; | |
818 | *bytes = (u64)(found_bits) * block_group->sectorsize; | |
819 | return 0; | |
820 | } | |
821 | ||
822 | return -1; | |
823 | } | |
824 | ||
825 | static struct btrfs_free_space *find_free_space(struct btrfs_block_group_cache | |
826 | *block_group, u64 *offset, | |
827 | u64 *bytes, int debug) | |
828 | { | |
829 | struct btrfs_free_space *entry; | |
830 | struct rb_node *node; | |
831 | int ret; | |
832 | ||
833 | if (!block_group->free_space_offset.rb_node) | |
834 | return NULL; | |
835 | ||
836 | entry = tree_search_offset(block_group, | |
837 | offset_to_bitmap(block_group, *offset), | |
838 | 0, 1); | |
839 | if (!entry) | |
840 | return NULL; | |
841 | ||
842 | for (node = &entry->offset_index; node; node = rb_next(node)) { | |
843 | entry = rb_entry(node, struct btrfs_free_space, offset_index); | |
844 | if (entry->bytes < *bytes) | |
845 | continue; | |
846 | ||
847 | if (entry->bitmap) { | |
848 | ret = search_bitmap(block_group, entry, offset, bytes); | |
849 | if (!ret) | |
850 | return entry; | |
851 | continue; | |
852 | } | |
853 | ||
854 | *offset = entry->offset; | |
855 | *bytes = entry->bytes; | |
856 | return entry; | |
857 | } | |
858 | ||
859 | return NULL; | |
860 | } | |
861 | ||
862 | static void add_new_bitmap(struct btrfs_block_group_cache *block_group, | |
863 | struct btrfs_free_space *info, u64 offset) | |
864 | { | |
865 | u64 bytes_per_bg = BITS_PER_BITMAP * block_group->sectorsize; | |
866 | int max_bitmaps = (int)div64_u64(block_group->key.offset + | |
867 | bytes_per_bg - 1, bytes_per_bg); | |
868 | BUG_ON(block_group->total_bitmaps >= max_bitmaps); | |
869 | ||
870 | info->offset = offset_to_bitmap(block_group, offset); | |
f019f426 | 871 | info->bytes = 0; |
96303081 JB |
872 | link_free_space(block_group, info); |
873 | block_group->total_bitmaps++; | |
874 | ||
875 | recalculate_thresholds(block_group); | |
876 | } | |
877 | ||
878 | static noinline int remove_from_bitmap(struct btrfs_block_group_cache *block_group, | |
879 | struct btrfs_free_space *bitmap_info, | |
880 | u64 *offset, u64 *bytes) | |
881 | { | |
882 | u64 end; | |
6606bb97 JB |
883 | u64 search_start, search_bytes; |
884 | int ret; | |
96303081 JB |
885 | |
886 | again: | |
887 | end = bitmap_info->offset + | |
888 | (u64)(BITS_PER_BITMAP * block_group->sectorsize) - 1; | |
889 | ||
6606bb97 JB |
890 | /* |
891 | * XXX - this can go away after a few releases. | |
892 | * | |
893 | * since the only user of btrfs_remove_free_space is the tree logging | |
894 | * stuff, and the only way to test that is under crash conditions, we | |
895 | * want to have this debug stuff here just in case somethings not | |
896 | * working. Search the bitmap for the space we are trying to use to | |
897 | * make sure its actually there. If its not there then we need to stop | |
898 | * because something has gone wrong. | |
899 | */ | |
900 | search_start = *offset; | |
901 | search_bytes = *bytes; | |
902 | ret = search_bitmap(block_group, bitmap_info, &search_start, | |
903 | &search_bytes); | |
904 | BUG_ON(ret < 0 || search_start != *offset); | |
905 | ||
96303081 | 906 | if (*offset > bitmap_info->offset && *offset + *bytes > end) { |
817d52f8 JB |
907 | bitmap_clear_bits(block_group, bitmap_info, *offset, |
908 | end - *offset + 1); | |
96303081 JB |
909 | *bytes -= end - *offset + 1; |
910 | *offset = end + 1; | |
911 | } else if (*offset >= bitmap_info->offset && *offset + *bytes <= end) { | |
817d52f8 | 912 | bitmap_clear_bits(block_group, bitmap_info, *offset, *bytes); |
96303081 JB |
913 | *bytes = 0; |
914 | } | |
915 | ||
916 | if (*bytes) { | |
6606bb97 | 917 | struct rb_node *next = rb_next(&bitmap_info->offset_index); |
96303081 JB |
918 | if (!bitmap_info->bytes) { |
919 | unlink_free_space(block_group, bitmap_info); | |
920 | kfree(bitmap_info->bitmap); | |
921 | kfree(bitmap_info); | |
922 | block_group->total_bitmaps--; | |
923 | recalculate_thresholds(block_group); | |
924 | } | |
925 | ||
6606bb97 JB |
926 | /* |
927 | * no entry after this bitmap, but we still have bytes to | |
928 | * remove, so something has gone wrong. | |
929 | */ | |
930 | if (!next) | |
96303081 JB |
931 | return -EINVAL; |
932 | ||
6606bb97 JB |
933 | bitmap_info = rb_entry(next, struct btrfs_free_space, |
934 | offset_index); | |
935 | ||
936 | /* | |
937 | * if the next entry isn't a bitmap we need to return to let the | |
938 | * extent stuff do its work. | |
939 | */ | |
96303081 JB |
940 | if (!bitmap_info->bitmap) |
941 | return -EAGAIN; | |
942 | ||
6606bb97 JB |
943 | /* |
944 | * Ok the next item is a bitmap, but it may not actually hold | |
945 | * the information for the rest of this free space stuff, so | |
946 | * look for it, and if we don't find it return so we can try | |
947 | * everything over again. | |
948 | */ | |
949 | search_start = *offset; | |
950 | search_bytes = *bytes; | |
951 | ret = search_bitmap(block_group, bitmap_info, &search_start, | |
952 | &search_bytes); | |
953 | if (ret < 0 || search_start != *offset) | |
954 | return -EAGAIN; | |
955 | ||
96303081 JB |
956 | goto again; |
957 | } else if (!bitmap_info->bytes) { | |
958 | unlink_free_space(block_group, bitmap_info); | |
959 | kfree(bitmap_info->bitmap); | |
960 | kfree(bitmap_info); | |
961 | block_group->total_bitmaps--; | |
962 | recalculate_thresholds(block_group); | |
963 | } | |
964 | ||
965 | return 0; | |
966 | } | |
967 | ||
968 | static int insert_into_bitmap(struct btrfs_block_group_cache *block_group, | |
969 | struct btrfs_free_space *info) | |
970 | { | |
971 | struct btrfs_free_space *bitmap_info; | |
972 | int added = 0; | |
973 | u64 bytes, offset, end; | |
974 | int ret; | |
975 | ||
976 | /* | |
977 | * If we are below the extents threshold then we can add this as an | |
978 | * extent, and don't have to deal with the bitmap | |
979 | */ | |
980 | if (block_group->free_extents < block_group->extents_thresh && | |
981 | info->bytes > block_group->sectorsize * 4) | |
982 | return 0; | |
983 | ||
984 | /* | |
985 | * some block groups are so tiny they can't be enveloped by a bitmap, so | |
986 | * don't even bother to create a bitmap for this | |
987 | */ | |
988 | if (BITS_PER_BITMAP * block_group->sectorsize > | |
989 | block_group->key.offset) | |
990 | return 0; | |
991 | ||
992 | bytes = info->bytes; | |
993 | offset = info->offset; | |
994 | ||
995 | again: | |
996 | bitmap_info = tree_search_offset(block_group, | |
997 | offset_to_bitmap(block_group, offset), | |
998 | 1, 0); | |
999 | if (!bitmap_info) { | |
1000 | BUG_ON(added); | |
1001 | goto new_bitmap; | |
1002 | } | |
1003 | ||
1004 | end = bitmap_info->offset + | |
1005 | (u64)(BITS_PER_BITMAP * block_group->sectorsize); | |
1006 | ||
1007 | if (offset >= bitmap_info->offset && offset + bytes > end) { | |
817d52f8 JB |
1008 | bitmap_set_bits(block_group, bitmap_info, offset, |
1009 | end - offset); | |
96303081 JB |
1010 | bytes -= end - offset; |
1011 | offset = end; | |
1012 | added = 0; | |
1013 | } else if (offset >= bitmap_info->offset && offset + bytes <= end) { | |
817d52f8 | 1014 | bitmap_set_bits(block_group, bitmap_info, offset, bytes); |
96303081 JB |
1015 | bytes = 0; |
1016 | } else { | |
1017 | BUG(); | |
1018 | } | |
1019 | ||
1020 | if (!bytes) { | |
1021 | ret = 1; | |
1022 | goto out; | |
1023 | } else | |
1024 | goto again; | |
1025 | ||
1026 | new_bitmap: | |
1027 | if (info && info->bitmap) { | |
1028 | add_new_bitmap(block_group, info, offset); | |
1029 | added = 1; | |
1030 | info = NULL; | |
1031 | goto again; | |
1032 | } else { | |
1033 | spin_unlock(&block_group->tree_lock); | |
1034 | ||
1035 | /* no pre-allocated info, allocate a new one */ | |
1036 | if (!info) { | |
1037 | info = kzalloc(sizeof(struct btrfs_free_space), | |
1038 | GFP_NOFS); | |
1039 | if (!info) { | |
1040 | spin_lock(&block_group->tree_lock); | |
1041 | ret = -ENOMEM; | |
1042 | goto out; | |
1043 | } | |
1044 | } | |
1045 | ||
1046 | /* allocate the bitmap */ | |
1047 | info->bitmap = kzalloc(PAGE_CACHE_SIZE, GFP_NOFS); | |
1048 | spin_lock(&block_group->tree_lock); | |
1049 | if (!info->bitmap) { | |
1050 | ret = -ENOMEM; | |
1051 | goto out; | |
1052 | } | |
1053 | goto again; | |
1054 | } | |
1055 | ||
1056 | out: | |
1057 | if (info) { | |
1058 | if (info->bitmap) | |
1059 | kfree(info->bitmap); | |
1060 | kfree(info); | |
1061 | } | |
0f9dd46c JB |
1062 | |
1063 | return ret; | |
1064 | } | |
1065 | ||
6226cb0a JB |
1066 | int btrfs_add_free_space(struct btrfs_block_group_cache *block_group, |
1067 | u64 offset, u64 bytes) | |
0f9dd46c | 1068 | { |
96303081 JB |
1069 | struct btrfs_free_space *right_info = NULL; |
1070 | struct btrfs_free_space *left_info = NULL; | |
0f9dd46c | 1071 | struct btrfs_free_space *info = NULL; |
0f9dd46c JB |
1072 | int ret = 0; |
1073 | ||
6226cb0a JB |
1074 | info = kzalloc(sizeof(struct btrfs_free_space), GFP_NOFS); |
1075 | if (!info) | |
1076 | return -ENOMEM; | |
1077 | ||
1078 | info->offset = offset; | |
1079 | info->bytes = bytes; | |
1080 | ||
1081 | spin_lock(&block_group->tree_lock); | |
1082 | ||
0f9dd46c JB |
1083 | /* |
1084 | * first we want to see if there is free space adjacent to the range we | |
1085 | * are adding, if there is remove that struct and add a new one to | |
1086 | * cover the entire range | |
1087 | */ | |
96303081 JB |
1088 | right_info = tree_search_offset(block_group, offset + bytes, 0, 0); |
1089 | if (right_info && rb_prev(&right_info->offset_index)) | |
1090 | left_info = rb_entry(rb_prev(&right_info->offset_index), | |
1091 | struct btrfs_free_space, offset_index); | |
1092 | else | |
1093 | left_info = tree_search_offset(block_group, offset - 1, 0, 0); | |
0f9dd46c | 1094 | |
96303081 JB |
1095 | /* |
1096 | * If there was no extent directly to the left or right of this new | |
1097 | * extent then we know we're going to have to allocate a new extent, so | |
1098 | * before we do that see if we need to drop this into a bitmap | |
1099 | */ | |
1100 | if ((!left_info || left_info->bitmap) && | |
1101 | (!right_info || right_info->bitmap)) { | |
1102 | ret = insert_into_bitmap(block_group, info); | |
1103 | ||
1104 | if (ret < 0) { | |
1105 | goto out; | |
1106 | } else if (ret) { | |
1107 | ret = 0; | |
1108 | goto out; | |
1109 | } | |
1110 | } | |
1111 | ||
1112 | if (right_info && !right_info->bitmap) { | |
0f9dd46c | 1113 | unlink_free_space(block_group, right_info); |
6226cb0a JB |
1114 | info->bytes += right_info->bytes; |
1115 | kfree(right_info); | |
0f9dd46c JB |
1116 | } |
1117 | ||
96303081 JB |
1118 | if (left_info && !left_info->bitmap && |
1119 | left_info->offset + left_info->bytes == offset) { | |
0f9dd46c | 1120 | unlink_free_space(block_group, left_info); |
6226cb0a JB |
1121 | info->offset = left_info->offset; |
1122 | info->bytes += left_info->bytes; | |
1123 | kfree(left_info); | |
0f9dd46c JB |
1124 | } |
1125 | ||
0f9dd46c JB |
1126 | ret = link_free_space(block_group, info); |
1127 | if (ret) | |
1128 | kfree(info); | |
96303081 | 1129 | out: |
6226cb0a JB |
1130 | spin_unlock(&block_group->tree_lock); |
1131 | ||
0f9dd46c | 1132 | if (ret) { |
96303081 | 1133 | printk(KERN_CRIT "btrfs: unable to add free space :%d\n", ret); |
c293498b | 1134 | BUG_ON(ret == -EEXIST); |
0f9dd46c JB |
1135 | } |
1136 | ||
0f9dd46c JB |
1137 | return ret; |
1138 | } | |
1139 | ||
6226cb0a JB |
1140 | int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group, |
1141 | u64 offset, u64 bytes) | |
0f9dd46c JB |
1142 | { |
1143 | struct btrfs_free_space *info; | |
96303081 | 1144 | struct btrfs_free_space *next_info = NULL; |
0f9dd46c JB |
1145 | int ret = 0; |
1146 | ||
6226cb0a JB |
1147 | spin_lock(&block_group->tree_lock); |
1148 | ||
96303081 JB |
1149 | again: |
1150 | info = tree_search_offset(block_group, offset, 0, 0); | |
1151 | if (!info) { | |
6606bb97 JB |
1152 | /* |
1153 | * oops didn't find an extent that matched the space we wanted | |
1154 | * to remove, look for a bitmap instead | |
1155 | */ | |
1156 | info = tree_search_offset(block_group, | |
1157 | offset_to_bitmap(block_group, offset), | |
1158 | 1, 0); | |
1159 | if (!info) { | |
1160 | WARN_ON(1); | |
1161 | goto out_lock; | |
1162 | } | |
96303081 JB |
1163 | } |
1164 | ||
1165 | if (info->bytes < bytes && rb_next(&info->offset_index)) { | |
1166 | u64 end; | |
1167 | next_info = rb_entry(rb_next(&info->offset_index), | |
1168 | struct btrfs_free_space, | |
1169 | offset_index); | |
1170 | ||
1171 | if (next_info->bitmap) | |
1172 | end = next_info->offset + BITS_PER_BITMAP * | |
1173 | block_group->sectorsize - 1; | |
1174 | else | |
1175 | end = next_info->offset + next_info->bytes; | |
1176 | ||
1177 | if (next_info->bytes < bytes || | |
1178 | next_info->offset > offset || offset > end) { | |
1179 | printk(KERN_CRIT "Found free space at %llu, size %llu," | |
1180 | " trying to use %llu\n", | |
1181 | (unsigned long long)info->offset, | |
1182 | (unsigned long long)info->bytes, | |
1183 | (unsigned long long)bytes); | |
0f9dd46c JB |
1184 | WARN_ON(1); |
1185 | ret = -EINVAL; | |
96303081 | 1186 | goto out_lock; |
0f9dd46c | 1187 | } |
0f9dd46c | 1188 | |
96303081 JB |
1189 | info = next_info; |
1190 | } | |
1191 | ||
1192 | if (info->bytes == bytes) { | |
1193 | unlink_free_space(block_group, info); | |
1194 | if (info->bitmap) { | |
1195 | kfree(info->bitmap); | |
1196 | block_group->total_bitmaps--; | |
0f9dd46c | 1197 | } |
96303081 JB |
1198 | kfree(info); |
1199 | goto out_lock; | |
1200 | } | |
0f9dd46c | 1201 | |
96303081 JB |
1202 | if (!info->bitmap && info->offset == offset) { |
1203 | unlink_free_space(block_group, info); | |
0f9dd46c JB |
1204 | info->offset += bytes; |
1205 | info->bytes -= bytes; | |
96303081 JB |
1206 | link_free_space(block_group, info); |
1207 | goto out_lock; | |
1208 | } | |
0f9dd46c | 1209 | |
96303081 JB |
1210 | if (!info->bitmap && info->offset <= offset && |
1211 | info->offset + info->bytes >= offset + bytes) { | |
9b49c9b9 CM |
1212 | u64 old_start = info->offset; |
1213 | /* | |
1214 | * we're freeing space in the middle of the info, | |
1215 | * this can happen during tree log replay | |
1216 | * | |
1217 | * first unlink the old info and then | |
1218 | * insert it again after the hole we're creating | |
1219 | */ | |
1220 | unlink_free_space(block_group, info); | |
1221 | if (offset + bytes < info->offset + info->bytes) { | |
1222 | u64 old_end = info->offset + info->bytes; | |
1223 | ||
1224 | info->offset = offset + bytes; | |
1225 | info->bytes = old_end - info->offset; | |
1226 | ret = link_free_space(block_group, info); | |
96303081 JB |
1227 | WARN_ON(ret); |
1228 | if (ret) | |
1229 | goto out_lock; | |
9b49c9b9 CM |
1230 | } else { |
1231 | /* the hole we're creating ends at the end | |
1232 | * of the info struct, just free the info | |
1233 | */ | |
1234 | kfree(info); | |
1235 | } | |
6226cb0a | 1236 | spin_unlock(&block_group->tree_lock); |
96303081 JB |
1237 | |
1238 | /* step two, insert a new info struct to cover | |
1239 | * anything before the hole | |
9b49c9b9 | 1240 | */ |
6226cb0a JB |
1241 | ret = btrfs_add_free_space(block_group, old_start, |
1242 | offset - old_start); | |
96303081 JB |
1243 | WARN_ON(ret); |
1244 | goto out; | |
0f9dd46c | 1245 | } |
96303081 JB |
1246 | |
1247 | ret = remove_from_bitmap(block_group, info, &offset, &bytes); | |
1248 | if (ret == -EAGAIN) | |
1249 | goto again; | |
1250 | BUG_ON(ret); | |
1251 | out_lock: | |
1252 | spin_unlock(&block_group->tree_lock); | |
0f9dd46c | 1253 | out: |
25179201 JB |
1254 | return ret; |
1255 | } | |
1256 | ||
0f9dd46c JB |
1257 | void btrfs_dump_free_space(struct btrfs_block_group_cache *block_group, |
1258 | u64 bytes) | |
1259 | { | |
1260 | struct btrfs_free_space *info; | |
1261 | struct rb_node *n; | |
1262 | int count = 0; | |
1263 | ||
1264 | for (n = rb_first(&block_group->free_space_offset); n; n = rb_next(n)) { | |
1265 | info = rb_entry(n, struct btrfs_free_space, offset_index); | |
1266 | if (info->bytes >= bytes) | |
1267 | count++; | |
96303081 | 1268 | printk(KERN_CRIT "entry offset %llu, bytes %llu, bitmap %s\n", |
21380931 | 1269 | (unsigned long long)info->offset, |
96303081 JB |
1270 | (unsigned long long)info->bytes, |
1271 | (info->bitmap) ? "yes" : "no"); | |
0f9dd46c | 1272 | } |
96303081 JB |
1273 | printk(KERN_INFO "block group has cluster?: %s\n", |
1274 | list_empty(&block_group->cluster_list) ? "no" : "yes"); | |
0f9dd46c JB |
1275 | printk(KERN_INFO "%d blocks of free space at or bigger than bytes is" |
1276 | "\n", count); | |
1277 | } | |
1278 | ||
1279 | u64 btrfs_block_group_free_space(struct btrfs_block_group_cache *block_group) | |
1280 | { | |
1281 | struct btrfs_free_space *info; | |
1282 | struct rb_node *n; | |
1283 | u64 ret = 0; | |
1284 | ||
1285 | for (n = rb_first(&block_group->free_space_offset); n; | |
1286 | n = rb_next(n)) { | |
1287 | info = rb_entry(n, struct btrfs_free_space, offset_index); | |
1288 | ret += info->bytes; | |
1289 | } | |
1290 | ||
1291 | return ret; | |
1292 | } | |
1293 | ||
fa9c0d79 CM |
1294 | /* |
1295 | * for a given cluster, put all of its extents back into the free | |
1296 | * space cache. If the block group passed doesn't match the block group | |
1297 | * pointed to by the cluster, someone else raced in and freed the | |
1298 | * cluster already. In that case, we just return without changing anything | |
1299 | */ | |
1300 | static int | |
1301 | __btrfs_return_cluster_to_free_space( | |
1302 | struct btrfs_block_group_cache *block_group, | |
1303 | struct btrfs_free_cluster *cluster) | |
1304 | { | |
1305 | struct btrfs_free_space *entry; | |
1306 | struct rb_node *node; | |
96303081 | 1307 | bool bitmap; |
fa9c0d79 CM |
1308 | |
1309 | spin_lock(&cluster->lock); | |
1310 | if (cluster->block_group != block_group) | |
1311 | goto out; | |
1312 | ||
96303081 JB |
1313 | bitmap = cluster->points_to_bitmap; |
1314 | cluster->block_group = NULL; | |
fa9c0d79 | 1315 | cluster->window_start = 0; |
96303081 JB |
1316 | list_del_init(&cluster->block_group_list); |
1317 | cluster->points_to_bitmap = false; | |
1318 | ||
1319 | if (bitmap) | |
1320 | goto out; | |
1321 | ||
fa9c0d79 | 1322 | node = rb_first(&cluster->root); |
96303081 | 1323 | while (node) { |
fa9c0d79 CM |
1324 | entry = rb_entry(node, struct btrfs_free_space, offset_index); |
1325 | node = rb_next(&entry->offset_index); | |
1326 | rb_erase(&entry->offset_index, &cluster->root); | |
96303081 JB |
1327 | BUG_ON(entry->bitmap); |
1328 | tree_insert_offset(&block_group->free_space_offset, | |
1329 | entry->offset, &entry->offset_index, 0); | |
fa9c0d79 | 1330 | } |
6bef4d31 | 1331 | cluster->root = RB_ROOT; |
96303081 | 1332 | |
fa9c0d79 CM |
1333 | out: |
1334 | spin_unlock(&cluster->lock); | |
96303081 | 1335 | btrfs_put_block_group(block_group); |
fa9c0d79 CM |
1336 | return 0; |
1337 | } | |
1338 | ||
0f9dd46c JB |
1339 | void btrfs_remove_free_space_cache(struct btrfs_block_group_cache *block_group) |
1340 | { | |
1341 | struct btrfs_free_space *info; | |
1342 | struct rb_node *node; | |
fa9c0d79 | 1343 | struct btrfs_free_cluster *cluster; |
96303081 | 1344 | struct list_head *head; |
0f9dd46c | 1345 | |
6226cb0a | 1346 | spin_lock(&block_group->tree_lock); |
96303081 JB |
1347 | while ((head = block_group->cluster_list.next) != |
1348 | &block_group->cluster_list) { | |
1349 | cluster = list_entry(head, struct btrfs_free_cluster, | |
1350 | block_group_list); | |
fa9c0d79 CM |
1351 | |
1352 | WARN_ON(cluster->block_group != block_group); | |
1353 | __btrfs_return_cluster_to_free_space(block_group, cluster); | |
96303081 JB |
1354 | if (need_resched()) { |
1355 | spin_unlock(&block_group->tree_lock); | |
1356 | cond_resched(); | |
1357 | spin_lock(&block_group->tree_lock); | |
1358 | } | |
fa9c0d79 CM |
1359 | } |
1360 | ||
96303081 JB |
1361 | while ((node = rb_last(&block_group->free_space_offset)) != NULL) { |
1362 | info = rb_entry(node, struct btrfs_free_space, offset_index); | |
0f9dd46c | 1363 | unlink_free_space(block_group, info); |
96303081 JB |
1364 | if (info->bitmap) |
1365 | kfree(info->bitmap); | |
0f9dd46c JB |
1366 | kfree(info); |
1367 | if (need_resched()) { | |
6226cb0a | 1368 | spin_unlock(&block_group->tree_lock); |
0f9dd46c | 1369 | cond_resched(); |
6226cb0a | 1370 | spin_lock(&block_group->tree_lock); |
0f9dd46c JB |
1371 | } |
1372 | } | |
96303081 | 1373 | |
6226cb0a | 1374 | spin_unlock(&block_group->tree_lock); |
0f9dd46c JB |
1375 | } |
1376 | ||
6226cb0a JB |
1377 | u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group, |
1378 | u64 offset, u64 bytes, u64 empty_size) | |
0f9dd46c | 1379 | { |
6226cb0a | 1380 | struct btrfs_free_space *entry = NULL; |
96303081 | 1381 | u64 bytes_search = bytes + empty_size; |
6226cb0a | 1382 | u64 ret = 0; |
0f9dd46c | 1383 | |
6226cb0a | 1384 | spin_lock(&block_group->tree_lock); |
96303081 | 1385 | entry = find_free_space(block_group, &offset, &bytes_search, 0); |
6226cb0a | 1386 | if (!entry) |
96303081 JB |
1387 | goto out; |
1388 | ||
1389 | ret = offset; | |
1390 | if (entry->bitmap) { | |
817d52f8 | 1391 | bitmap_clear_bits(block_group, entry, offset, bytes); |
96303081 JB |
1392 | if (!entry->bytes) { |
1393 | unlink_free_space(block_group, entry); | |
1394 | kfree(entry->bitmap); | |
1395 | kfree(entry); | |
1396 | block_group->total_bitmaps--; | |
1397 | recalculate_thresholds(block_group); | |
1398 | } | |
1399 | } else { | |
6226cb0a | 1400 | unlink_free_space(block_group, entry); |
6226cb0a JB |
1401 | entry->offset += bytes; |
1402 | entry->bytes -= bytes; | |
6226cb0a JB |
1403 | if (!entry->bytes) |
1404 | kfree(entry); | |
1405 | else | |
1406 | link_free_space(block_group, entry); | |
1407 | } | |
0f9dd46c | 1408 | |
96303081 JB |
1409 | out: |
1410 | spin_unlock(&block_group->tree_lock); | |
817d52f8 | 1411 | |
0f9dd46c JB |
1412 | return ret; |
1413 | } | |
fa9c0d79 CM |
1414 | |
1415 | /* | |
1416 | * given a cluster, put all of its extents back into the free space | |
1417 | * cache. If a block group is passed, this function will only free | |
1418 | * a cluster that belongs to the passed block group. | |
1419 | * | |
1420 | * Otherwise, it'll get a reference on the block group pointed to by the | |
1421 | * cluster and remove the cluster from it. | |
1422 | */ | |
1423 | int btrfs_return_cluster_to_free_space( | |
1424 | struct btrfs_block_group_cache *block_group, | |
1425 | struct btrfs_free_cluster *cluster) | |
1426 | { | |
1427 | int ret; | |
1428 | ||
1429 | /* first, get a safe pointer to the block group */ | |
1430 | spin_lock(&cluster->lock); | |
1431 | if (!block_group) { | |
1432 | block_group = cluster->block_group; | |
1433 | if (!block_group) { | |
1434 | spin_unlock(&cluster->lock); | |
1435 | return 0; | |
1436 | } | |
1437 | } else if (cluster->block_group != block_group) { | |
1438 | /* someone else has already freed it don't redo their work */ | |
1439 | spin_unlock(&cluster->lock); | |
1440 | return 0; | |
1441 | } | |
1442 | atomic_inc(&block_group->count); | |
1443 | spin_unlock(&cluster->lock); | |
1444 | ||
1445 | /* now return any extents the cluster had on it */ | |
1446 | spin_lock(&block_group->tree_lock); | |
1447 | ret = __btrfs_return_cluster_to_free_space(block_group, cluster); | |
1448 | spin_unlock(&block_group->tree_lock); | |
1449 | ||
1450 | /* finally drop our ref */ | |
1451 | btrfs_put_block_group(block_group); | |
1452 | return ret; | |
1453 | } | |
1454 | ||
96303081 JB |
1455 | static u64 btrfs_alloc_from_bitmap(struct btrfs_block_group_cache *block_group, |
1456 | struct btrfs_free_cluster *cluster, | |
1457 | u64 bytes, u64 min_start) | |
1458 | { | |
1459 | struct btrfs_free_space *entry; | |
1460 | int err; | |
1461 | u64 search_start = cluster->window_start; | |
1462 | u64 search_bytes = bytes; | |
1463 | u64 ret = 0; | |
1464 | ||
1465 | spin_lock(&block_group->tree_lock); | |
1466 | spin_lock(&cluster->lock); | |
1467 | ||
1468 | if (!cluster->points_to_bitmap) | |
1469 | goto out; | |
1470 | ||
1471 | if (cluster->block_group != block_group) | |
1472 | goto out; | |
1473 | ||
6606bb97 JB |
1474 | /* |
1475 | * search_start is the beginning of the bitmap, but at some point it may | |
1476 | * be a good idea to point to the actual start of the free area in the | |
1477 | * bitmap, so do the offset_to_bitmap trick anyway, and set bitmap_only | |
1478 | * to 1 to make sure we get the bitmap entry | |
1479 | */ | |
1480 | entry = tree_search_offset(block_group, | |
1481 | offset_to_bitmap(block_group, search_start), | |
1482 | 1, 0); | |
96303081 JB |
1483 | if (!entry || !entry->bitmap) |
1484 | goto out; | |
1485 | ||
1486 | search_start = min_start; | |
1487 | search_bytes = bytes; | |
1488 | ||
1489 | err = search_bitmap(block_group, entry, &search_start, | |
1490 | &search_bytes); | |
1491 | if (err) | |
1492 | goto out; | |
1493 | ||
1494 | ret = search_start; | |
817d52f8 | 1495 | bitmap_clear_bits(block_group, entry, ret, bytes); |
96303081 JB |
1496 | out: |
1497 | spin_unlock(&cluster->lock); | |
1498 | spin_unlock(&block_group->tree_lock); | |
1499 | ||
1500 | return ret; | |
1501 | } | |
1502 | ||
fa9c0d79 CM |
1503 | /* |
1504 | * given a cluster, try to allocate 'bytes' from it, returns 0 | |
1505 | * if it couldn't find anything suitably large, or a logical disk offset | |
1506 | * if things worked out | |
1507 | */ | |
1508 | u64 btrfs_alloc_from_cluster(struct btrfs_block_group_cache *block_group, | |
1509 | struct btrfs_free_cluster *cluster, u64 bytes, | |
1510 | u64 min_start) | |
1511 | { | |
1512 | struct btrfs_free_space *entry = NULL; | |
1513 | struct rb_node *node; | |
1514 | u64 ret = 0; | |
1515 | ||
96303081 JB |
1516 | if (cluster->points_to_bitmap) |
1517 | return btrfs_alloc_from_bitmap(block_group, cluster, bytes, | |
1518 | min_start); | |
1519 | ||
fa9c0d79 CM |
1520 | spin_lock(&cluster->lock); |
1521 | if (bytes > cluster->max_size) | |
1522 | goto out; | |
1523 | ||
1524 | if (cluster->block_group != block_group) | |
1525 | goto out; | |
1526 | ||
1527 | node = rb_first(&cluster->root); | |
1528 | if (!node) | |
1529 | goto out; | |
1530 | ||
1531 | entry = rb_entry(node, struct btrfs_free_space, offset_index); | |
1532 | ||
1533 | while(1) { | |
1534 | if (entry->bytes < bytes || entry->offset < min_start) { | |
1535 | struct rb_node *node; | |
1536 | ||
1537 | node = rb_next(&entry->offset_index); | |
1538 | if (!node) | |
1539 | break; | |
1540 | entry = rb_entry(node, struct btrfs_free_space, | |
1541 | offset_index); | |
1542 | continue; | |
1543 | } | |
1544 | ret = entry->offset; | |
1545 | ||
1546 | entry->offset += bytes; | |
1547 | entry->bytes -= bytes; | |
1548 | ||
1549 | if (entry->bytes == 0) { | |
1550 | rb_erase(&entry->offset_index, &cluster->root); | |
1551 | kfree(entry); | |
1552 | } | |
1553 | break; | |
1554 | } | |
1555 | out: | |
1556 | spin_unlock(&cluster->lock); | |
96303081 | 1557 | |
fa9c0d79 CM |
1558 | return ret; |
1559 | } | |
1560 | ||
96303081 JB |
1561 | static int btrfs_bitmap_cluster(struct btrfs_block_group_cache *block_group, |
1562 | struct btrfs_free_space *entry, | |
1563 | struct btrfs_free_cluster *cluster, | |
1564 | u64 offset, u64 bytes, u64 min_bytes) | |
1565 | { | |
1566 | unsigned long next_zero; | |
1567 | unsigned long i; | |
1568 | unsigned long search_bits; | |
1569 | unsigned long total_bits; | |
1570 | unsigned long found_bits; | |
1571 | unsigned long start = 0; | |
1572 | unsigned long total_found = 0; | |
1573 | bool found = false; | |
1574 | ||
1575 | i = offset_to_bit(entry->offset, block_group->sectorsize, | |
1576 | max_t(u64, offset, entry->offset)); | |
1577 | search_bits = bytes_to_bits(min_bytes, block_group->sectorsize); | |
1578 | total_bits = bytes_to_bits(bytes, block_group->sectorsize); | |
1579 | ||
1580 | again: | |
1581 | found_bits = 0; | |
1582 | for (i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, i); | |
1583 | i < BITS_PER_BITMAP; | |
1584 | i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, i + 1)) { | |
1585 | next_zero = find_next_zero_bit(entry->bitmap, | |
1586 | BITS_PER_BITMAP, i); | |
1587 | if (next_zero - i >= search_bits) { | |
1588 | found_bits = next_zero - i; | |
1589 | break; | |
1590 | } | |
1591 | i = next_zero; | |
1592 | } | |
1593 | ||
1594 | if (!found_bits) | |
1595 | return -1; | |
1596 | ||
1597 | if (!found) { | |
1598 | start = i; | |
1599 | found = true; | |
1600 | } | |
1601 | ||
1602 | total_found += found_bits; | |
1603 | ||
1604 | if (cluster->max_size < found_bits * block_group->sectorsize) | |
1605 | cluster->max_size = found_bits * block_group->sectorsize; | |
1606 | ||
1607 | if (total_found < total_bits) { | |
1608 | i = find_next_bit(entry->bitmap, BITS_PER_BITMAP, next_zero); | |
1609 | if (i - start > total_bits * 2) { | |
1610 | total_found = 0; | |
1611 | cluster->max_size = 0; | |
1612 | found = false; | |
1613 | } | |
1614 | goto again; | |
1615 | } | |
1616 | ||
1617 | cluster->window_start = start * block_group->sectorsize + | |
1618 | entry->offset; | |
1619 | cluster->points_to_bitmap = true; | |
1620 | ||
1621 | return 0; | |
1622 | } | |
1623 | ||
fa9c0d79 CM |
1624 | /* |
1625 | * here we try to find a cluster of blocks in a block group. The goal | |
1626 | * is to find at least bytes free and up to empty_size + bytes free. | |
1627 | * We might not find them all in one contiguous area. | |
1628 | * | |
1629 | * returns zero and sets up cluster if things worked out, otherwise | |
1630 | * it returns -enospc | |
1631 | */ | |
1632 | int btrfs_find_space_cluster(struct btrfs_trans_handle *trans, | |
451d7585 | 1633 | struct btrfs_root *root, |
fa9c0d79 CM |
1634 | struct btrfs_block_group_cache *block_group, |
1635 | struct btrfs_free_cluster *cluster, | |
1636 | u64 offset, u64 bytes, u64 empty_size) | |
1637 | { | |
1638 | struct btrfs_free_space *entry = NULL; | |
1639 | struct rb_node *node; | |
1640 | struct btrfs_free_space *next; | |
96303081 | 1641 | struct btrfs_free_space *last = NULL; |
fa9c0d79 CM |
1642 | u64 min_bytes; |
1643 | u64 window_start; | |
1644 | u64 window_free; | |
1645 | u64 max_extent = 0; | |
96303081 | 1646 | bool found_bitmap = false; |
fa9c0d79 CM |
1647 | int ret; |
1648 | ||
1649 | /* for metadata, allow allocates with more holes */ | |
451d7585 CM |
1650 | if (btrfs_test_opt(root, SSD_SPREAD)) { |
1651 | min_bytes = bytes + empty_size; | |
1652 | } else if (block_group->flags & BTRFS_BLOCK_GROUP_METADATA) { | |
fa9c0d79 CM |
1653 | /* |
1654 | * we want to do larger allocations when we are | |
1655 | * flushing out the delayed refs, it helps prevent | |
1656 | * making more work as we go along. | |
1657 | */ | |
1658 | if (trans->transaction->delayed_refs.flushing) | |
1659 | min_bytes = max(bytes, (bytes + empty_size) >> 1); | |
1660 | else | |
1661 | min_bytes = max(bytes, (bytes + empty_size) >> 4); | |
1662 | } else | |
1663 | min_bytes = max(bytes, (bytes + empty_size) >> 2); | |
1664 | ||
1665 | spin_lock(&block_group->tree_lock); | |
1666 | spin_lock(&cluster->lock); | |
1667 | ||
1668 | /* someone already found a cluster, hooray */ | |
1669 | if (cluster->block_group) { | |
1670 | ret = 0; | |
1671 | goto out; | |
1672 | } | |
1673 | again: | |
96303081 | 1674 | entry = tree_search_offset(block_group, offset, found_bitmap, 1); |
fa9c0d79 CM |
1675 | if (!entry) { |
1676 | ret = -ENOSPC; | |
1677 | goto out; | |
1678 | } | |
96303081 JB |
1679 | |
1680 | /* | |
1681 | * If found_bitmap is true, we exhausted our search for extent entries, | |
1682 | * and we just want to search all of the bitmaps that we can find, and | |
1683 | * ignore any extent entries we find. | |
1684 | */ | |
1685 | while (entry->bitmap || found_bitmap || | |
1686 | (!entry->bitmap && entry->bytes < min_bytes)) { | |
1687 | struct rb_node *node = rb_next(&entry->offset_index); | |
1688 | ||
1689 | if (entry->bitmap && entry->bytes > bytes + empty_size) { | |
1690 | ret = btrfs_bitmap_cluster(block_group, entry, cluster, | |
1691 | offset, bytes + empty_size, | |
1692 | min_bytes); | |
1693 | if (!ret) | |
1694 | goto got_it; | |
1695 | } | |
1696 | ||
1697 | if (!node) { | |
1698 | ret = -ENOSPC; | |
1699 | goto out; | |
1700 | } | |
1701 | entry = rb_entry(node, struct btrfs_free_space, offset_index); | |
1702 | } | |
1703 | ||
1704 | /* | |
1705 | * We already searched all the extent entries from the passed in offset | |
1706 | * to the end and didn't find enough space for the cluster, and we also | |
1707 | * didn't find any bitmaps that met our criteria, just go ahead and exit | |
1708 | */ | |
1709 | if (found_bitmap) { | |
1710 | ret = -ENOSPC; | |
1711 | goto out; | |
1712 | } | |
1713 | ||
1714 | cluster->points_to_bitmap = false; | |
fa9c0d79 CM |
1715 | window_start = entry->offset; |
1716 | window_free = entry->bytes; | |
1717 | last = entry; | |
1718 | max_extent = entry->bytes; | |
1719 | ||
96303081 | 1720 | while (1) { |
fa9c0d79 CM |
1721 | /* out window is just right, lets fill it */ |
1722 | if (window_free >= bytes + empty_size) | |
1723 | break; | |
1724 | ||
1725 | node = rb_next(&last->offset_index); | |
1726 | if (!node) { | |
96303081 JB |
1727 | if (found_bitmap) |
1728 | goto again; | |
fa9c0d79 CM |
1729 | ret = -ENOSPC; |
1730 | goto out; | |
1731 | } | |
1732 | next = rb_entry(node, struct btrfs_free_space, offset_index); | |
1733 | ||
96303081 JB |
1734 | /* |
1735 | * we found a bitmap, so if this search doesn't result in a | |
1736 | * cluster, we know to go and search again for the bitmaps and | |
1737 | * start looking for space there | |
1738 | */ | |
1739 | if (next->bitmap) { | |
1740 | if (!found_bitmap) | |
1741 | offset = next->offset; | |
1742 | found_bitmap = true; | |
1743 | last = next; | |
1744 | continue; | |
1745 | } | |
1746 | ||
fa9c0d79 CM |
1747 | /* |
1748 | * we haven't filled the empty size and the window is | |
1749 | * very large. reset and try again | |
1750 | */ | |
c6044801 CM |
1751 | if (next->offset - (last->offset + last->bytes) > 128 * 1024 || |
1752 | next->offset - window_start > (bytes + empty_size) * 2) { | |
fa9c0d79 CM |
1753 | entry = next; |
1754 | window_start = entry->offset; | |
1755 | window_free = entry->bytes; | |
1756 | last = entry; | |
01dea1ef | 1757 | max_extent = entry->bytes; |
fa9c0d79 CM |
1758 | } else { |
1759 | last = next; | |
1760 | window_free += next->bytes; | |
1761 | if (entry->bytes > max_extent) | |
1762 | max_extent = entry->bytes; | |
1763 | } | |
1764 | } | |
1765 | ||
1766 | cluster->window_start = entry->offset; | |
1767 | ||
1768 | /* | |
1769 | * now we've found our entries, pull them out of the free space | |
1770 | * cache and put them into the cluster rbtree | |
1771 | * | |
1772 | * The cluster includes an rbtree, but only uses the offset index | |
1773 | * of each free space cache entry. | |
1774 | */ | |
96303081 | 1775 | while (1) { |
fa9c0d79 | 1776 | node = rb_next(&entry->offset_index); |
96303081 JB |
1777 | if (entry->bitmap && node) { |
1778 | entry = rb_entry(node, struct btrfs_free_space, | |
1779 | offset_index); | |
1780 | continue; | |
1781 | } else if (entry->bitmap && !node) { | |
1782 | break; | |
1783 | } | |
1784 | ||
1785 | rb_erase(&entry->offset_index, &block_group->free_space_offset); | |
fa9c0d79 | 1786 | ret = tree_insert_offset(&cluster->root, entry->offset, |
96303081 | 1787 | &entry->offset_index, 0); |
fa9c0d79 CM |
1788 | BUG_ON(ret); |
1789 | ||
1790 | if (!node || entry == last) | |
1791 | break; | |
1792 | ||
1793 | entry = rb_entry(node, struct btrfs_free_space, offset_index); | |
1794 | } | |
96303081 | 1795 | |
fa9c0d79 | 1796 | cluster->max_size = max_extent; |
96303081 JB |
1797 | got_it: |
1798 | ret = 0; | |
fa9c0d79 CM |
1799 | atomic_inc(&block_group->count); |
1800 | list_add_tail(&cluster->block_group_list, &block_group->cluster_list); | |
1801 | cluster->block_group = block_group; | |
1802 | out: | |
1803 | spin_unlock(&cluster->lock); | |
1804 | spin_unlock(&block_group->tree_lock); | |
1805 | ||
1806 | return ret; | |
1807 | } | |
1808 | ||
1809 | /* | |
1810 | * simple code to zero out a cluster | |
1811 | */ | |
1812 | void btrfs_init_free_cluster(struct btrfs_free_cluster *cluster) | |
1813 | { | |
1814 | spin_lock_init(&cluster->lock); | |
1815 | spin_lock_init(&cluster->refill_lock); | |
6bef4d31 | 1816 | cluster->root = RB_ROOT; |
fa9c0d79 | 1817 | cluster->max_size = 0; |
96303081 | 1818 | cluster->points_to_bitmap = false; |
fa9c0d79 CM |
1819 | INIT_LIST_HEAD(&cluster->block_group_list); |
1820 | cluster->block_group = NULL; | |
1821 | } | |
1822 |