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5d4f98a2 YZ |
1 | /* |
2 | * Copyright (C) 2009 Oracle. All rights reserved. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or | |
5 | * modify it under the terms of the GNU General Public | |
6 | * License v2 as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
11 | * General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public | |
14 | * License along with this program; if not, write to the | |
15 | * Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
16 | * Boston, MA 021110-1307, USA. | |
17 | */ | |
18 | ||
19 | #include <linux/sched.h> | |
20 | #include <linux/pagemap.h> | |
21 | #include <linux/writeback.h> | |
22 | #include <linux/blkdev.h> | |
23 | #include <linux/rbtree.h> | |
5a0e3ad6 | 24 | #include <linux/slab.h> |
5d4f98a2 YZ |
25 | #include "ctree.h" |
26 | #include "disk-io.h" | |
27 | #include "transaction.h" | |
28 | #include "volumes.h" | |
29 | #include "locking.h" | |
30 | #include "btrfs_inode.h" | |
31 | #include "async-thread.h" | |
0af3d00b | 32 | #include "free-space-cache.h" |
581bb050 | 33 | #include "inode-map.h" |
5d4f98a2 YZ |
34 | |
35 | /* | |
36 | * backref_node, mapping_node and tree_block start with this | |
37 | */ | |
38 | struct tree_entry { | |
39 | struct rb_node rb_node; | |
40 | u64 bytenr; | |
41 | }; | |
42 | ||
43 | /* | |
44 | * present a tree block in the backref cache | |
45 | */ | |
46 | struct backref_node { | |
47 | struct rb_node rb_node; | |
48 | u64 bytenr; | |
3fd0a558 YZ |
49 | |
50 | u64 new_bytenr; | |
51 | /* objectid of tree block owner, can be not uptodate */ | |
5d4f98a2 | 52 | u64 owner; |
3fd0a558 YZ |
53 | /* link to pending, changed or detached list */ |
54 | struct list_head list; | |
5d4f98a2 YZ |
55 | /* list of upper level blocks reference this block */ |
56 | struct list_head upper; | |
57 | /* list of child blocks in the cache */ | |
58 | struct list_head lower; | |
59 | /* NULL if this node is not tree root */ | |
60 | struct btrfs_root *root; | |
61 | /* extent buffer got by COW the block */ | |
62 | struct extent_buffer *eb; | |
63 | /* level of tree block */ | |
64 | unsigned int level:8; | |
3fd0a558 YZ |
65 | /* is the block in non-reference counted tree */ |
66 | unsigned int cowonly:1; | |
67 | /* 1 if no child node in the cache */ | |
5d4f98a2 YZ |
68 | unsigned int lowest:1; |
69 | /* is the extent buffer locked */ | |
70 | unsigned int locked:1; | |
71 | /* has the block been processed */ | |
72 | unsigned int processed:1; | |
73 | /* have backrefs of this block been checked */ | |
74 | unsigned int checked:1; | |
3fd0a558 YZ |
75 | /* |
76 | * 1 if corresponding block has been cowed but some upper | |
77 | * level block pointers may not point to the new location | |
78 | */ | |
79 | unsigned int pending:1; | |
80 | /* | |
81 | * 1 if the backref node isn't connected to any other | |
82 | * backref node. | |
83 | */ | |
84 | unsigned int detached:1; | |
5d4f98a2 YZ |
85 | }; |
86 | ||
87 | /* | |
88 | * present a block pointer in the backref cache | |
89 | */ | |
90 | struct backref_edge { | |
91 | struct list_head list[2]; | |
92 | struct backref_node *node[2]; | |
5d4f98a2 YZ |
93 | }; |
94 | ||
95 | #define LOWER 0 | |
96 | #define UPPER 1 | |
97 | ||
98 | struct backref_cache { | |
99 | /* red black tree of all backref nodes in the cache */ | |
100 | struct rb_root rb_root; | |
3fd0a558 YZ |
101 | /* for passing backref nodes to btrfs_reloc_cow_block */ |
102 | struct backref_node *path[BTRFS_MAX_LEVEL]; | |
103 | /* | |
104 | * list of blocks that have been cowed but some block | |
105 | * pointers in upper level blocks may not reflect the | |
106 | * new location | |
107 | */ | |
5d4f98a2 | 108 | struct list_head pending[BTRFS_MAX_LEVEL]; |
3fd0a558 YZ |
109 | /* list of backref nodes with no child node */ |
110 | struct list_head leaves; | |
111 | /* list of blocks that have been cowed in current transaction */ | |
112 | struct list_head changed; | |
113 | /* list of detached backref node. */ | |
114 | struct list_head detached; | |
115 | ||
116 | u64 last_trans; | |
117 | ||
118 | int nr_nodes; | |
119 | int nr_edges; | |
5d4f98a2 YZ |
120 | }; |
121 | ||
122 | /* | |
123 | * map address of tree root to tree | |
124 | */ | |
125 | struct mapping_node { | |
126 | struct rb_node rb_node; | |
127 | u64 bytenr; | |
128 | void *data; | |
129 | }; | |
130 | ||
131 | struct mapping_tree { | |
132 | struct rb_root rb_root; | |
133 | spinlock_t lock; | |
134 | }; | |
135 | ||
136 | /* | |
137 | * present a tree block to process | |
138 | */ | |
139 | struct tree_block { | |
140 | struct rb_node rb_node; | |
141 | u64 bytenr; | |
142 | struct btrfs_key key; | |
143 | unsigned int level:8; | |
144 | unsigned int key_ready:1; | |
145 | }; | |
146 | ||
0257bb82 YZ |
147 | #define MAX_EXTENTS 128 |
148 | ||
149 | struct file_extent_cluster { | |
150 | u64 start; | |
151 | u64 end; | |
152 | u64 boundary[MAX_EXTENTS]; | |
153 | unsigned int nr; | |
154 | }; | |
155 | ||
5d4f98a2 YZ |
156 | struct reloc_control { |
157 | /* block group to relocate */ | |
158 | struct btrfs_block_group_cache *block_group; | |
159 | /* extent tree */ | |
160 | struct btrfs_root *extent_root; | |
161 | /* inode for moving data */ | |
162 | struct inode *data_inode; | |
3fd0a558 YZ |
163 | |
164 | struct btrfs_block_rsv *block_rsv; | |
165 | ||
166 | struct backref_cache backref_cache; | |
167 | ||
168 | struct file_extent_cluster cluster; | |
5d4f98a2 YZ |
169 | /* tree blocks have been processed */ |
170 | struct extent_io_tree processed_blocks; | |
171 | /* map start of tree root to corresponding reloc tree */ | |
172 | struct mapping_tree reloc_root_tree; | |
173 | /* list of reloc trees */ | |
174 | struct list_head reloc_roots; | |
3fd0a558 YZ |
175 | /* size of metadata reservation for merging reloc trees */ |
176 | u64 merging_rsv_size; | |
177 | /* size of relocated tree nodes */ | |
178 | u64 nodes_relocated; | |
179 | ||
5d4f98a2 YZ |
180 | u64 search_start; |
181 | u64 extents_found; | |
3fd0a558 | 182 | |
3fd0a558 YZ |
183 | unsigned int stage:8; |
184 | unsigned int create_reloc_tree:1; | |
185 | unsigned int merge_reloc_tree:1; | |
5d4f98a2 | 186 | unsigned int found_file_extent:1; |
3fd0a558 | 187 | unsigned int commit_transaction:1; |
5d4f98a2 YZ |
188 | }; |
189 | ||
190 | /* stages of data relocation */ | |
191 | #define MOVE_DATA_EXTENTS 0 | |
192 | #define UPDATE_DATA_PTRS 1 | |
193 | ||
3fd0a558 YZ |
194 | static void remove_backref_node(struct backref_cache *cache, |
195 | struct backref_node *node); | |
196 | static void __mark_block_processed(struct reloc_control *rc, | |
197 | struct backref_node *node); | |
5d4f98a2 YZ |
198 | |
199 | static void mapping_tree_init(struct mapping_tree *tree) | |
200 | { | |
6bef4d31 | 201 | tree->rb_root = RB_ROOT; |
5d4f98a2 YZ |
202 | spin_lock_init(&tree->lock); |
203 | } | |
204 | ||
205 | static void backref_cache_init(struct backref_cache *cache) | |
206 | { | |
207 | int i; | |
6bef4d31 | 208 | cache->rb_root = RB_ROOT; |
5d4f98a2 YZ |
209 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) |
210 | INIT_LIST_HEAD(&cache->pending[i]); | |
3fd0a558 YZ |
211 | INIT_LIST_HEAD(&cache->changed); |
212 | INIT_LIST_HEAD(&cache->detached); | |
213 | INIT_LIST_HEAD(&cache->leaves); | |
214 | } | |
215 | ||
216 | static void backref_cache_cleanup(struct backref_cache *cache) | |
217 | { | |
218 | struct backref_node *node; | |
219 | int i; | |
220 | ||
221 | while (!list_empty(&cache->detached)) { | |
222 | node = list_entry(cache->detached.next, | |
223 | struct backref_node, list); | |
224 | remove_backref_node(cache, node); | |
225 | } | |
226 | ||
227 | while (!list_empty(&cache->leaves)) { | |
228 | node = list_entry(cache->leaves.next, | |
229 | struct backref_node, lower); | |
230 | remove_backref_node(cache, node); | |
231 | } | |
232 | ||
233 | cache->last_trans = 0; | |
234 | ||
235 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) | |
236 | BUG_ON(!list_empty(&cache->pending[i])); | |
237 | BUG_ON(!list_empty(&cache->changed)); | |
238 | BUG_ON(!list_empty(&cache->detached)); | |
239 | BUG_ON(!RB_EMPTY_ROOT(&cache->rb_root)); | |
240 | BUG_ON(cache->nr_nodes); | |
241 | BUG_ON(cache->nr_edges); | |
242 | } | |
243 | ||
244 | static struct backref_node *alloc_backref_node(struct backref_cache *cache) | |
245 | { | |
246 | struct backref_node *node; | |
247 | ||
248 | node = kzalloc(sizeof(*node), GFP_NOFS); | |
249 | if (node) { | |
250 | INIT_LIST_HEAD(&node->list); | |
251 | INIT_LIST_HEAD(&node->upper); | |
252 | INIT_LIST_HEAD(&node->lower); | |
253 | RB_CLEAR_NODE(&node->rb_node); | |
254 | cache->nr_nodes++; | |
255 | } | |
256 | return node; | |
257 | } | |
258 | ||
259 | static void free_backref_node(struct backref_cache *cache, | |
260 | struct backref_node *node) | |
261 | { | |
262 | if (node) { | |
263 | cache->nr_nodes--; | |
264 | kfree(node); | |
265 | } | |
266 | } | |
267 | ||
268 | static struct backref_edge *alloc_backref_edge(struct backref_cache *cache) | |
269 | { | |
270 | struct backref_edge *edge; | |
271 | ||
272 | edge = kzalloc(sizeof(*edge), GFP_NOFS); | |
273 | if (edge) | |
274 | cache->nr_edges++; | |
275 | return edge; | |
5d4f98a2 YZ |
276 | } |
277 | ||
3fd0a558 YZ |
278 | static void free_backref_edge(struct backref_cache *cache, |
279 | struct backref_edge *edge) | |
5d4f98a2 | 280 | { |
3fd0a558 YZ |
281 | if (edge) { |
282 | cache->nr_edges--; | |
283 | kfree(edge); | |
284 | } | |
5d4f98a2 YZ |
285 | } |
286 | ||
287 | static struct rb_node *tree_insert(struct rb_root *root, u64 bytenr, | |
288 | struct rb_node *node) | |
289 | { | |
290 | struct rb_node **p = &root->rb_node; | |
291 | struct rb_node *parent = NULL; | |
292 | struct tree_entry *entry; | |
293 | ||
294 | while (*p) { | |
295 | parent = *p; | |
296 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
297 | ||
298 | if (bytenr < entry->bytenr) | |
299 | p = &(*p)->rb_left; | |
300 | else if (bytenr > entry->bytenr) | |
301 | p = &(*p)->rb_right; | |
302 | else | |
303 | return parent; | |
304 | } | |
305 | ||
306 | rb_link_node(node, parent, p); | |
307 | rb_insert_color(node, root); | |
308 | return NULL; | |
309 | } | |
310 | ||
311 | static struct rb_node *tree_search(struct rb_root *root, u64 bytenr) | |
312 | { | |
313 | struct rb_node *n = root->rb_node; | |
314 | struct tree_entry *entry; | |
315 | ||
316 | while (n) { | |
317 | entry = rb_entry(n, struct tree_entry, rb_node); | |
318 | ||
319 | if (bytenr < entry->bytenr) | |
320 | n = n->rb_left; | |
321 | else if (bytenr > entry->bytenr) | |
322 | n = n->rb_right; | |
323 | else | |
324 | return n; | |
325 | } | |
326 | return NULL; | |
327 | } | |
328 | ||
329 | /* | |
330 | * walk up backref nodes until reach node presents tree root | |
331 | */ | |
332 | static struct backref_node *walk_up_backref(struct backref_node *node, | |
333 | struct backref_edge *edges[], | |
334 | int *index) | |
335 | { | |
336 | struct backref_edge *edge; | |
337 | int idx = *index; | |
338 | ||
339 | while (!list_empty(&node->upper)) { | |
340 | edge = list_entry(node->upper.next, | |
341 | struct backref_edge, list[LOWER]); | |
342 | edges[idx++] = edge; | |
343 | node = edge->node[UPPER]; | |
344 | } | |
3fd0a558 | 345 | BUG_ON(node->detached); |
5d4f98a2 YZ |
346 | *index = idx; |
347 | return node; | |
348 | } | |
349 | ||
350 | /* | |
351 | * walk down backref nodes to find start of next reference path | |
352 | */ | |
353 | static struct backref_node *walk_down_backref(struct backref_edge *edges[], | |
354 | int *index) | |
355 | { | |
356 | struct backref_edge *edge; | |
357 | struct backref_node *lower; | |
358 | int idx = *index; | |
359 | ||
360 | while (idx > 0) { | |
361 | edge = edges[idx - 1]; | |
362 | lower = edge->node[LOWER]; | |
363 | if (list_is_last(&edge->list[LOWER], &lower->upper)) { | |
364 | idx--; | |
365 | continue; | |
366 | } | |
367 | edge = list_entry(edge->list[LOWER].next, | |
368 | struct backref_edge, list[LOWER]); | |
369 | edges[idx - 1] = edge; | |
370 | *index = idx; | |
371 | return edge->node[UPPER]; | |
372 | } | |
373 | *index = 0; | |
374 | return NULL; | |
375 | } | |
376 | ||
3fd0a558 YZ |
377 | static void unlock_node_buffer(struct backref_node *node) |
378 | { | |
379 | if (node->locked) { | |
380 | btrfs_tree_unlock(node->eb); | |
381 | node->locked = 0; | |
382 | } | |
383 | } | |
384 | ||
5d4f98a2 YZ |
385 | static void drop_node_buffer(struct backref_node *node) |
386 | { | |
387 | if (node->eb) { | |
3fd0a558 | 388 | unlock_node_buffer(node); |
5d4f98a2 YZ |
389 | free_extent_buffer(node->eb); |
390 | node->eb = NULL; | |
391 | } | |
392 | } | |
393 | ||
394 | static void drop_backref_node(struct backref_cache *tree, | |
395 | struct backref_node *node) | |
396 | { | |
5d4f98a2 YZ |
397 | BUG_ON(!list_empty(&node->upper)); |
398 | ||
399 | drop_node_buffer(node); | |
3fd0a558 | 400 | list_del(&node->list); |
5d4f98a2 | 401 | list_del(&node->lower); |
3fd0a558 YZ |
402 | if (!RB_EMPTY_NODE(&node->rb_node)) |
403 | rb_erase(&node->rb_node, &tree->rb_root); | |
404 | free_backref_node(tree, node); | |
5d4f98a2 YZ |
405 | } |
406 | ||
407 | /* | |
408 | * remove a backref node from the backref cache | |
409 | */ | |
410 | static void remove_backref_node(struct backref_cache *cache, | |
411 | struct backref_node *node) | |
412 | { | |
413 | struct backref_node *upper; | |
414 | struct backref_edge *edge; | |
415 | ||
416 | if (!node) | |
417 | return; | |
418 | ||
3fd0a558 | 419 | BUG_ON(!node->lowest && !node->detached); |
5d4f98a2 YZ |
420 | while (!list_empty(&node->upper)) { |
421 | edge = list_entry(node->upper.next, struct backref_edge, | |
422 | list[LOWER]); | |
423 | upper = edge->node[UPPER]; | |
424 | list_del(&edge->list[LOWER]); | |
425 | list_del(&edge->list[UPPER]); | |
3fd0a558 YZ |
426 | free_backref_edge(cache, edge); |
427 | ||
428 | if (RB_EMPTY_NODE(&upper->rb_node)) { | |
429 | BUG_ON(!list_empty(&node->upper)); | |
430 | drop_backref_node(cache, node); | |
431 | node = upper; | |
432 | node->lowest = 1; | |
433 | continue; | |
434 | } | |
5d4f98a2 | 435 | /* |
3fd0a558 | 436 | * add the node to leaf node list if no other |
5d4f98a2 YZ |
437 | * child block cached. |
438 | */ | |
439 | if (list_empty(&upper->lower)) { | |
3fd0a558 | 440 | list_add_tail(&upper->lower, &cache->leaves); |
5d4f98a2 YZ |
441 | upper->lowest = 1; |
442 | } | |
443 | } | |
3fd0a558 | 444 | |
5d4f98a2 YZ |
445 | drop_backref_node(cache, node); |
446 | } | |
447 | ||
3fd0a558 YZ |
448 | static void update_backref_node(struct backref_cache *cache, |
449 | struct backref_node *node, u64 bytenr) | |
450 | { | |
451 | struct rb_node *rb_node; | |
452 | rb_erase(&node->rb_node, &cache->rb_root); | |
453 | node->bytenr = bytenr; | |
454 | rb_node = tree_insert(&cache->rb_root, node->bytenr, &node->rb_node); | |
455 | BUG_ON(rb_node); | |
456 | } | |
457 | ||
458 | /* | |
459 | * update backref cache after a transaction commit | |
460 | */ | |
461 | static int update_backref_cache(struct btrfs_trans_handle *trans, | |
462 | struct backref_cache *cache) | |
463 | { | |
464 | struct backref_node *node; | |
465 | int level = 0; | |
466 | ||
467 | if (cache->last_trans == 0) { | |
468 | cache->last_trans = trans->transid; | |
469 | return 0; | |
470 | } | |
471 | ||
472 | if (cache->last_trans == trans->transid) | |
473 | return 0; | |
474 | ||
475 | /* | |
476 | * detached nodes are used to avoid unnecessary backref | |
477 | * lookup. transaction commit changes the extent tree. | |
478 | * so the detached nodes are no longer useful. | |
479 | */ | |
480 | while (!list_empty(&cache->detached)) { | |
481 | node = list_entry(cache->detached.next, | |
482 | struct backref_node, list); | |
483 | remove_backref_node(cache, node); | |
484 | } | |
485 | ||
486 | while (!list_empty(&cache->changed)) { | |
487 | node = list_entry(cache->changed.next, | |
488 | struct backref_node, list); | |
489 | list_del_init(&node->list); | |
490 | BUG_ON(node->pending); | |
491 | update_backref_node(cache, node, node->new_bytenr); | |
492 | } | |
493 | ||
494 | /* | |
495 | * some nodes can be left in the pending list if there were | |
496 | * errors during processing the pending nodes. | |
497 | */ | |
498 | for (level = 0; level < BTRFS_MAX_LEVEL; level++) { | |
499 | list_for_each_entry(node, &cache->pending[level], list) { | |
500 | BUG_ON(!node->pending); | |
501 | if (node->bytenr == node->new_bytenr) | |
502 | continue; | |
503 | update_backref_node(cache, node, node->new_bytenr); | |
504 | } | |
505 | } | |
506 | ||
507 | cache->last_trans = 0; | |
508 | return 1; | |
509 | } | |
510 | ||
f2a97a9d | 511 | |
3fd0a558 YZ |
512 | static int should_ignore_root(struct btrfs_root *root) |
513 | { | |
514 | struct btrfs_root *reloc_root; | |
515 | ||
516 | if (!root->ref_cows) | |
517 | return 0; | |
518 | ||
519 | reloc_root = root->reloc_root; | |
520 | if (!reloc_root) | |
521 | return 0; | |
522 | ||
523 | if (btrfs_root_last_snapshot(&reloc_root->root_item) == | |
524 | root->fs_info->running_transaction->transid - 1) | |
525 | return 0; | |
526 | /* | |
527 | * if there is reloc tree and it was created in previous | |
528 | * transaction backref lookup can find the reloc tree, | |
529 | * so backref node for the fs tree root is useless for | |
530 | * relocation. | |
531 | */ | |
532 | return 1; | |
533 | } | |
5d4f98a2 YZ |
534 | /* |
535 | * find reloc tree by address of tree root | |
536 | */ | |
537 | static struct btrfs_root *find_reloc_root(struct reloc_control *rc, | |
538 | u64 bytenr) | |
539 | { | |
540 | struct rb_node *rb_node; | |
541 | struct mapping_node *node; | |
542 | struct btrfs_root *root = NULL; | |
543 | ||
544 | spin_lock(&rc->reloc_root_tree.lock); | |
545 | rb_node = tree_search(&rc->reloc_root_tree.rb_root, bytenr); | |
546 | if (rb_node) { | |
547 | node = rb_entry(rb_node, struct mapping_node, rb_node); | |
548 | root = (struct btrfs_root *)node->data; | |
549 | } | |
550 | spin_unlock(&rc->reloc_root_tree.lock); | |
551 | return root; | |
552 | } | |
553 | ||
554 | static int is_cowonly_root(u64 root_objectid) | |
555 | { | |
556 | if (root_objectid == BTRFS_ROOT_TREE_OBJECTID || | |
557 | root_objectid == BTRFS_EXTENT_TREE_OBJECTID || | |
558 | root_objectid == BTRFS_CHUNK_TREE_OBJECTID || | |
559 | root_objectid == BTRFS_DEV_TREE_OBJECTID || | |
560 | root_objectid == BTRFS_TREE_LOG_OBJECTID || | |
561 | root_objectid == BTRFS_CSUM_TREE_OBJECTID) | |
562 | return 1; | |
563 | return 0; | |
564 | } | |
565 | ||
566 | static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info, | |
567 | u64 root_objectid) | |
568 | { | |
569 | struct btrfs_key key; | |
570 | ||
571 | key.objectid = root_objectid; | |
572 | key.type = BTRFS_ROOT_ITEM_KEY; | |
573 | if (is_cowonly_root(root_objectid)) | |
574 | key.offset = 0; | |
575 | else | |
576 | key.offset = (u64)-1; | |
577 | ||
578 | return btrfs_read_fs_root_no_name(fs_info, &key); | |
579 | } | |
580 | ||
581 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
582 | static noinline_for_stack | |
583 | struct btrfs_root *find_tree_root(struct reloc_control *rc, | |
584 | struct extent_buffer *leaf, | |
585 | struct btrfs_extent_ref_v0 *ref0) | |
586 | { | |
587 | struct btrfs_root *root; | |
588 | u64 root_objectid = btrfs_ref_root_v0(leaf, ref0); | |
589 | u64 generation = btrfs_ref_generation_v0(leaf, ref0); | |
590 | ||
591 | BUG_ON(root_objectid == BTRFS_TREE_RELOC_OBJECTID); | |
592 | ||
593 | root = read_fs_root(rc->extent_root->fs_info, root_objectid); | |
594 | BUG_ON(IS_ERR(root)); | |
595 | ||
596 | if (root->ref_cows && | |
597 | generation != btrfs_root_generation(&root->root_item)) | |
598 | return NULL; | |
599 | ||
600 | return root; | |
601 | } | |
602 | #endif | |
603 | ||
604 | static noinline_for_stack | |
605 | int find_inline_backref(struct extent_buffer *leaf, int slot, | |
606 | unsigned long *ptr, unsigned long *end) | |
607 | { | |
608 | struct btrfs_extent_item *ei; | |
609 | struct btrfs_tree_block_info *bi; | |
610 | u32 item_size; | |
611 | ||
612 | item_size = btrfs_item_size_nr(leaf, slot); | |
613 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
614 | if (item_size < sizeof(*ei)) { | |
615 | WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0)); | |
616 | return 1; | |
617 | } | |
618 | #endif | |
619 | ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item); | |
620 | WARN_ON(!(btrfs_extent_flags(leaf, ei) & | |
621 | BTRFS_EXTENT_FLAG_TREE_BLOCK)); | |
622 | ||
623 | if (item_size <= sizeof(*ei) + sizeof(*bi)) { | |
624 | WARN_ON(item_size < sizeof(*ei) + sizeof(*bi)); | |
625 | return 1; | |
626 | } | |
627 | ||
628 | bi = (struct btrfs_tree_block_info *)(ei + 1); | |
629 | *ptr = (unsigned long)(bi + 1); | |
630 | *end = (unsigned long)ei + item_size; | |
631 | return 0; | |
632 | } | |
633 | ||
634 | /* | |
635 | * build backref tree for a given tree block. root of the backref tree | |
636 | * corresponds the tree block, leaves of the backref tree correspond | |
637 | * roots of b-trees that reference the tree block. | |
638 | * | |
639 | * the basic idea of this function is check backrefs of a given block | |
640 | * to find upper level blocks that refernece the block, and then check | |
641 | * bakcrefs of these upper level blocks recursively. the recursion stop | |
642 | * when tree root is reached or backrefs for the block is cached. | |
643 | * | |
644 | * NOTE: if we find backrefs for a block are cached, we know backrefs | |
645 | * for all upper level blocks that directly/indirectly reference the | |
646 | * block are also cached. | |
647 | */ | |
3fd0a558 YZ |
648 | static noinline_for_stack |
649 | struct backref_node *build_backref_tree(struct reloc_control *rc, | |
650 | struct btrfs_key *node_key, | |
651 | int level, u64 bytenr) | |
5d4f98a2 | 652 | { |
3fd0a558 | 653 | struct backref_cache *cache = &rc->backref_cache; |
5d4f98a2 YZ |
654 | struct btrfs_path *path1; |
655 | struct btrfs_path *path2; | |
656 | struct extent_buffer *eb; | |
657 | struct btrfs_root *root; | |
658 | struct backref_node *cur; | |
659 | struct backref_node *upper; | |
660 | struct backref_node *lower; | |
661 | struct backref_node *node = NULL; | |
662 | struct backref_node *exist = NULL; | |
663 | struct backref_edge *edge; | |
664 | struct rb_node *rb_node; | |
665 | struct btrfs_key key; | |
666 | unsigned long end; | |
667 | unsigned long ptr; | |
668 | LIST_HEAD(list); | |
3fd0a558 YZ |
669 | LIST_HEAD(useless); |
670 | int cowonly; | |
5d4f98a2 YZ |
671 | int ret; |
672 | int err = 0; | |
673 | ||
674 | path1 = btrfs_alloc_path(); | |
675 | path2 = btrfs_alloc_path(); | |
676 | if (!path1 || !path2) { | |
677 | err = -ENOMEM; | |
678 | goto out; | |
679 | } | |
026fd317 JB |
680 | path1->reada = 1; |
681 | path2->reada = 2; | |
5d4f98a2 | 682 | |
3fd0a558 | 683 | node = alloc_backref_node(cache); |
5d4f98a2 YZ |
684 | if (!node) { |
685 | err = -ENOMEM; | |
686 | goto out; | |
687 | } | |
688 | ||
5d4f98a2 | 689 | node->bytenr = bytenr; |
5d4f98a2 YZ |
690 | node->level = level; |
691 | node->lowest = 1; | |
692 | cur = node; | |
693 | again: | |
694 | end = 0; | |
695 | ptr = 0; | |
696 | key.objectid = cur->bytenr; | |
697 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
698 | key.offset = (u64)-1; | |
699 | ||
700 | path1->search_commit_root = 1; | |
701 | path1->skip_locking = 1; | |
702 | ret = btrfs_search_slot(NULL, rc->extent_root, &key, path1, | |
703 | 0, 0); | |
704 | if (ret < 0) { | |
705 | err = ret; | |
706 | goto out; | |
707 | } | |
708 | BUG_ON(!ret || !path1->slots[0]); | |
709 | ||
710 | path1->slots[0]--; | |
711 | ||
712 | WARN_ON(cur->checked); | |
713 | if (!list_empty(&cur->upper)) { | |
714 | /* | |
715 | * the backref was added previously when processsing | |
716 | * backref of type BTRFS_TREE_BLOCK_REF_KEY | |
717 | */ | |
718 | BUG_ON(!list_is_singular(&cur->upper)); | |
719 | edge = list_entry(cur->upper.next, struct backref_edge, | |
720 | list[LOWER]); | |
721 | BUG_ON(!list_empty(&edge->list[UPPER])); | |
722 | exist = edge->node[UPPER]; | |
723 | /* | |
724 | * add the upper level block to pending list if we need | |
725 | * check its backrefs | |
726 | */ | |
727 | if (!exist->checked) | |
728 | list_add_tail(&edge->list[UPPER], &list); | |
729 | } else { | |
730 | exist = NULL; | |
731 | } | |
732 | ||
733 | while (1) { | |
734 | cond_resched(); | |
735 | eb = path1->nodes[0]; | |
736 | ||
737 | if (ptr >= end) { | |
738 | if (path1->slots[0] >= btrfs_header_nritems(eb)) { | |
739 | ret = btrfs_next_leaf(rc->extent_root, path1); | |
740 | if (ret < 0) { | |
741 | err = ret; | |
742 | goto out; | |
743 | } | |
744 | if (ret > 0) | |
745 | break; | |
746 | eb = path1->nodes[0]; | |
747 | } | |
748 | ||
749 | btrfs_item_key_to_cpu(eb, &key, path1->slots[0]); | |
750 | if (key.objectid != cur->bytenr) { | |
751 | WARN_ON(exist); | |
752 | break; | |
753 | } | |
754 | ||
755 | if (key.type == BTRFS_EXTENT_ITEM_KEY) { | |
756 | ret = find_inline_backref(eb, path1->slots[0], | |
757 | &ptr, &end); | |
758 | if (ret) | |
759 | goto next; | |
760 | } | |
761 | } | |
762 | ||
763 | if (ptr < end) { | |
764 | /* update key for inline back ref */ | |
765 | struct btrfs_extent_inline_ref *iref; | |
766 | iref = (struct btrfs_extent_inline_ref *)ptr; | |
767 | key.type = btrfs_extent_inline_ref_type(eb, iref); | |
768 | key.offset = btrfs_extent_inline_ref_offset(eb, iref); | |
769 | WARN_ON(key.type != BTRFS_TREE_BLOCK_REF_KEY && | |
770 | key.type != BTRFS_SHARED_BLOCK_REF_KEY); | |
771 | } | |
772 | ||
773 | if (exist && | |
774 | ((key.type == BTRFS_TREE_BLOCK_REF_KEY && | |
775 | exist->owner == key.offset) || | |
776 | (key.type == BTRFS_SHARED_BLOCK_REF_KEY && | |
777 | exist->bytenr == key.offset))) { | |
778 | exist = NULL; | |
779 | goto next; | |
780 | } | |
781 | ||
782 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
783 | if (key.type == BTRFS_SHARED_BLOCK_REF_KEY || | |
784 | key.type == BTRFS_EXTENT_REF_V0_KEY) { | |
3fd0a558 | 785 | if (key.type == BTRFS_EXTENT_REF_V0_KEY) { |
5d4f98a2 YZ |
786 | struct btrfs_extent_ref_v0 *ref0; |
787 | ref0 = btrfs_item_ptr(eb, path1->slots[0], | |
788 | struct btrfs_extent_ref_v0); | |
3fd0a558 | 789 | if (key.objectid == key.offset) { |
046f264f | 790 | root = find_tree_root(rc, eb, ref0); |
3fd0a558 YZ |
791 | if (root && !should_ignore_root(root)) |
792 | cur->root = root; | |
793 | else | |
794 | list_add(&cur->list, &useless); | |
795 | break; | |
796 | } | |
046f264f YZ |
797 | if (is_cowonly_root(btrfs_ref_root_v0(eb, |
798 | ref0))) | |
799 | cur->cowonly = 1; | |
5d4f98a2 YZ |
800 | } |
801 | #else | |
802 | BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY); | |
803 | if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) { | |
804 | #endif | |
805 | if (key.objectid == key.offset) { | |
806 | /* | |
807 | * only root blocks of reloc trees use | |
808 | * backref of this type. | |
809 | */ | |
810 | root = find_reloc_root(rc, cur->bytenr); | |
811 | BUG_ON(!root); | |
812 | cur->root = root; | |
813 | break; | |
814 | } | |
815 | ||
3fd0a558 | 816 | edge = alloc_backref_edge(cache); |
5d4f98a2 YZ |
817 | if (!edge) { |
818 | err = -ENOMEM; | |
819 | goto out; | |
820 | } | |
821 | rb_node = tree_search(&cache->rb_root, key.offset); | |
822 | if (!rb_node) { | |
3fd0a558 | 823 | upper = alloc_backref_node(cache); |
5d4f98a2 | 824 | if (!upper) { |
3fd0a558 | 825 | free_backref_edge(cache, edge); |
5d4f98a2 YZ |
826 | err = -ENOMEM; |
827 | goto out; | |
828 | } | |
5d4f98a2 | 829 | upper->bytenr = key.offset; |
5d4f98a2 YZ |
830 | upper->level = cur->level + 1; |
831 | /* | |
832 | * backrefs for the upper level block isn't | |
833 | * cached, add the block to pending list | |
834 | */ | |
835 | list_add_tail(&edge->list[UPPER], &list); | |
836 | } else { | |
837 | upper = rb_entry(rb_node, struct backref_node, | |
838 | rb_node); | |
3fd0a558 | 839 | BUG_ON(!upper->checked); |
5d4f98a2 YZ |
840 | INIT_LIST_HEAD(&edge->list[UPPER]); |
841 | } | |
3fd0a558 | 842 | list_add_tail(&edge->list[LOWER], &cur->upper); |
5d4f98a2 | 843 | edge->node[LOWER] = cur; |
3fd0a558 | 844 | edge->node[UPPER] = upper; |
5d4f98a2 YZ |
845 | |
846 | goto next; | |
847 | } else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) { | |
848 | goto next; | |
849 | } | |
850 | ||
851 | /* key.type == BTRFS_TREE_BLOCK_REF_KEY */ | |
852 | root = read_fs_root(rc->extent_root->fs_info, key.offset); | |
853 | if (IS_ERR(root)) { | |
854 | err = PTR_ERR(root); | |
855 | goto out; | |
856 | } | |
857 | ||
3fd0a558 YZ |
858 | if (!root->ref_cows) |
859 | cur->cowonly = 1; | |
860 | ||
5d4f98a2 YZ |
861 | if (btrfs_root_level(&root->root_item) == cur->level) { |
862 | /* tree root */ | |
863 | BUG_ON(btrfs_root_bytenr(&root->root_item) != | |
864 | cur->bytenr); | |
3fd0a558 YZ |
865 | if (should_ignore_root(root)) |
866 | list_add(&cur->list, &useless); | |
867 | else | |
868 | cur->root = root; | |
5d4f98a2 YZ |
869 | break; |
870 | } | |
871 | ||
872 | level = cur->level + 1; | |
873 | ||
874 | /* | |
875 | * searching the tree to find upper level blocks | |
876 | * reference the block. | |
877 | */ | |
878 | path2->search_commit_root = 1; | |
879 | path2->skip_locking = 1; | |
880 | path2->lowest_level = level; | |
881 | ret = btrfs_search_slot(NULL, root, node_key, path2, 0, 0); | |
882 | path2->lowest_level = 0; | |
883 | if (ret < 0) { | |
884 | err = ret; | |
885 | goto out; | |
886 | } | |
33c66f43 YZ |
887 | if (ret > 0 && path2->slots[level] > 0) |
888 | path2->slots[level]--; | |
5d4f98a2 YZ |
889 | |
890 | eb = path2->nodes[level]; | |
891 | WARN_ON(btrfs_node_blockptr(eb, path2->slots[level]) != | |
892 | cur->bytenr); | |
893 | ||
894 | lower = cur; | |
895 | for (; level < BTRFS_MAX_LEVEL; level++) { | |
896 | if (!path2->nodes[level]) { | |
897 | BUG_ON(btrfs_root_bytenr(&root->root_item) != | |
898 | lower->bytenr); | |
3fd0a558 YZ |
899 | if (should_ignore_root(root)) |
900 | list_add(&lower->list, &useless); | |
901 | else | |
902 | lower->root = root; | |
5d4f98a2 YZ |
903 | break; |
904 | } | |
905 | ||
3fd0a558 | 906 | edge = alloc_backref_edge(cache); |
5d4f98a2 YZ |
907 | if (!edge) { |
908 | err = -ENOMEM; | |
909 | goto out; | |
910 | } | |
911 | ||
912 | eb = path2->nodes[level]; | |
913 | rb_node = tree_search(&cache->rb_root, eb->start); | |
914 | if (!rb_node) { | |
3fd0a558 | 915 | upper = alloc_backref_node(cache); |
5d4f98a2 | 916 | if (!upper) { |
3fd0a558 | 917 | free_backref_edge(cache, edge); |
5d4f98a2 YZ |
918 | err = -ENOMEM; |
919 | goto out; | |
920 | } | |
5d4f98a2 YZ |
921 | upper->bytenr = eb->start; |
922 | upper->owner = btrfs_header_owner(eb); | |
923 | upper->level = lower->level + 1; | |
3fd0a558 YZ |
924 | if (!root->ref_cows) |
925 | upper->cowonly = 1; | |
5d4f98a2 YZ |
926 | |
927 | /* | |
928 | * if we know the block isn't shared | |
929 | * we can void checking its backrefs. | |
930 | */ | |
931 | if (btrfs_block_can_be_shared(root, eb)) | |
932 | upper->checked = 0; | |
933 | else | |
934 | upper->checked = 1; | |
935 | ||
936 | /* | |
937 | * add the block to pending list if we | |
938 | * need check its backrefs. only block | |
939 | * at 'cur->level + 1' is added to the | |
940 | * tail of pending list. this guarantees | |
941 | * we check backrefs from lower level | |
942 | * blocks to upper level blocks. | |
943 | */ | |
944 | if (!upper->checked && | |
945 | level == cur->level + 1) { | |
946 | list_add_tail(&edge->list[UPPER], | |
947 | &list); | |
948 | } else | |
949 | INIT_LIST_HEAD(&edge->list[UPPER]); | |
950 | } else { | |
951 | upper = rb_entry(rb_node, struct backref_node, | |
952 | rb_node); | |
953 | BUG_ON(!upper->checked); | |
954 | INIT_LIST_HEAD(&edge->list[UPPER]); | |
3fd0a558 YZ |
955 | if (!upper->owner) |
956 | upper->owner = btrfs_header_owner(eb); | |
5d4f98a2 YZ |
957 | } |
958 | list_add_tail(&edge->list[LOWER], &lower->upper); | |
5d4f98a2 | 959 | edge->node[LOWER] = lower; |
3fd0a558 | 960 | edge->node[UPPER] = upper; |
5d4f98a2 YZ |
961 | |
962 | if (rb_node) | |
963 | break; | |
964 | lower = upper; | |
965 | upper = NULL; | |
966 | } | |
b3b4aa74 | 967 | btrfs_release_path(path2); |
5d4f98a2 YZ |
968 | next: |
969 | if (ptr < end) { | |
970 | ptr += btrfs_extent_inline_ref_size(key.type); | |
971 | if (ptr >= end) { | |
972 | WARN_ON(ptr > end); | |
973 | ptr = 0; | |
974 | end = 0; | |
975 | } | |
976 | } | |
977 | if (ptr >= end) | |
978 | path1->slots[0]++; | |
979 | } | |
b3b4aa74 | 980 | btrfs_release_path(path1); |
5d4f98a2 YZ |
981 | |
982 | cur->checked = 1; | |
983 | WARN_ON(exist); | |
984 | ||
985 | /* the pending list isn't empty, take the first block to process */ | |
986 | if (!list_empty(&list)) { | |
987 | edge = list_entry(list.next, struct backref_edge, list[UPPER]); | |
988 | list_del_init(&edge->list[UPPER]); | |
989 | cur = edge->node[UPPER]; | |
990 | goto again; | |
991 | } | |
992 | ||
993 | /* | |
994 | * everything goes well, connect backref nodes and insert backref nodes | |
995 | * into the cache. | |
996 | */ | |
997 | BUG_ON(!node->checked); | |
3fd0a558 YZ |
998 | cowonly = node->cowonly; |
999 | if (!cowonly) { | |
1000 | rb_node = tree_insert(&cache->rb_root, node->bytenr, | |
1001 | &node->rb_node); | |
1002 | BUG_ON(rb_node); | |
1003 | list_add_tail(&node->lower, &cache->leaves); | |
1004 | } | |
5d4f98a2 YZ |
1005 | |
1006 | list_for_each_entry(edge, &node->upper, list[LOWER]) | |
1007 | list_add_tail(&edge->list[UPPER], &list); | |
1008 | ||
1009 | while (!list_empty(&list)) { | |
1010 | edge = list_entry(list.next, struct backref_edge, list[UPPER]); | |
1011 | list_del_init(&edge->list[UPPER]); | |
1012 | upper = edge->node[UPPER]; | |
3fd0a558 YZ |
1013 | if (upper->detached) { |
1014 | list_del(&edge->list[LOWER]); | |
1015 | lower = edge->node[LOWER]; | |
1016 | free_backref_edge(cache, edge); | |
1017 | if (list_empty(&lower->upper)) | |
1018 | list_add(&lower->list, &useless); | |
1019 | continue; | |
1020 | } | |
5d4f98a2 YZ |
1021 | |
1022 | if (!RB_EMPTY_NODE(&upper->rb_node)) { | |
1023 | if (upper->lowest) { | |
1024 | list_del_init(&upper->lower); | |
1025 | upper->lowest = 0; | |
1026 | } | |
1027 | ||
1028 | list_add_tail(&edge->list[UPPER], &upper->lower); | |
1029 | continue; | |
1030 | } | |
1031 | ||
1032 | BUG_ON(!upper->checked); | |
3fd0a558 YZ |
1033 | BUG_ON(cowonly != upper->cowonly); |
1034 | if (!cowonly) { | |
1035 | rb_node = tree_insert(&cache->rb_root, upper->bytenr, | |
1036 | &upper->rb_node); | |
1037 | BUG_ON(rb_node); | |
1038 | } | |
5d4f98a2 YZ |
1039 | |
1040 | list_add_tail(&edge->list[UPPER], &upper->lower); | |
1041 | ||
1042 | list_for_each_entry(edge, &upper->upper, list[LOWER]) | |
1043 | list_add_tail(&edge->list[UPPER], &list); | |
1044 | } | |
3fd0a558 YZ |
1045 | /* |
1046 | * process useless backref nodes. backref nodes for tree leaves | |
1047 | * are deleted from the cache. backref nodes for upper level | |
1048 | * tree blocks are left in the cache to avoid unnecessary backref | |
1049 | * lookup. | |
1050 | */ | |
1051 | while (!list_empty(&useless)) { | |
1052 | upper = list_entry(useless.next, struct backref_node, list); | |
1053 | list_del_init(&upper->list); | |
1054 | BUG_ON(!list_empty(&upper->upper)); | |
1055 | if (upper == node) | |
1056 | node = NULL; | |
1057 | if (upper->lowest) { | |
1058 | list_del_init(&upper->lower); | |
1059 | upper->lowest = 0; | |
1060 | } | |
1061 | while (!list_empty(&upper->lower)) { | |
1062 | edge = list_entry(upper->lower.next, | |
1063 | struct backref_edge, list[UPPER]); | |
1064 | list_del(&edge->list[UPPER]); | |
1065 | list_del(&edge->list[LOWER]); | |
1066 | lower = edge->node[LOWER]; | |
1067 | free_backref_edge(cache, edge); | |
1068 | ||
1069 | if (list_empty(&lower->upper)) | |
1070 | list_add(&lower->list, &useless); | |
1071 | } | |
1072 | __mark_block_processed(rc, upper); | |
1073 | if (upper->level > 0) { | |
1074 | list_add(&upper->list, &cache->detached); | |
1075 | upper->detached = 1; | |
1076 | } else { | |
1077 | rb_erase(&upper->rb_node, &cache->rb_root); | |
1078 | free_backref_node(cache, upper); | |
1079 | } | |
1080 | } | |
5d4f98a2 YZ |
1081 | out: |
1082 | btrfs_free_path(path1); | |
1083 | btrfs_free_path(path2); | |
1084 | if (err) { | |
3fd0a558 YZ |
1085 | while (!list_empty(&useless)) { |
1086 | lower = list_entry(useless.next, | |
1087 | struct backref_node, upper); | |
1088 | list_del_init(&lower->upper); | |
1089 | } | |
5d4f98a2 | 1090 | upper = node; |
3fd0a558 | 1091 | INIT_LIST_HEAD(&list); |
5d4f98a2 YZ |
1092 | while (upper) { |
1093 | if (RB_EMPTY_NODE(&upper->rb_node)) { | |
1094 | list_splice_tail(&upper->upper, &list); | |
3fd0a558 | 1095 | free_backref_node(cache, upper); |
5d4f98a2 YZ |
1096 | } |
1097 | ||
1098 | if (list_empty(&list)) | |
1099 | break; | |
1100 | ||
1101 | edge = list_entry(list.next, struct backref_edge, | |
1102 | list[LOWER]); | |
3fd0a558 | 1103 | list_del(&edge->list[LOWER]); |
5d4f98a2 | 1104 | upper = edge->node[UPPER]; |
3fd0a558 | 1105 | free_backref_edge(cache, edge); |
5d4f98a2 YZ |
1106 | } |
1107 | return ERR_PTR(err); | |
1108 | } | |
3fd0a558 | 1109 | BUG_ON(node && node->detached); |
5d4f98a2 YZ |
1110 | return node; |
1111 | } | |
1112 | ||
3fd0a558 YZ |
1113 | /* |
1114 | * helper to add backref node for the newly created snapshot. | |
1115 | * the backref node is created by cloning backref node that | |
1116 | * corresponds to root of source tree | |
1117 | */ | |
1118 | static int clone_backref_node(struct btrfs_trans_handle *trans, | |
1119 | struct reloc_control *rc, | |
1120 | struct btrfs_root *src, | |
1121 | struct btrfs_root *dest) | |
1122 | { | |
1123 | struct btrfs_root *reloc_root = src->reloc_root; | |
1124 | struct backref_cache *cache = &rc->backref_cache; | |
1125 | struct backref_node *node = NULL; | |
1126 | struct backref_node *new_node; | |
1127 | struct backref_edge *edge; | |
1128 | struct backref_edge *new_edge; | |
1129 | struct rb_node *rb_node; | |
1130 | ||
1131 | if (cache->last_trans > 0) | |
1132 | update_backref_cache(trans, cache); | |
1133 | ||
1134 | rb_node = tree_search(&cache->rb_root, src->commit_root->start); | |
1135 | if (rb_node) { | |
1136 | node = rb_entry(rb_node, struct backref_node, rb_node); | |
1137 | if (node->detached) | |
1138 | node = NULL; | |
1139 | else | |
1140 | BUG_ON(node->new_bytenr != reloc_root->node->start); | |
1141 | } | |
1142 | ||
1143 | if (!node) { | |
1144 | rb_node = tree_search(&cache->rb_root, | |
1145 | reloc_root->commit_root->start); | |
1146 | if (rb_node) { | |
1147 | node = rb_entry(rb_node, struct backref_node, | |
1148 | rb_node); | |
1149 | BUG_ON(node->detached); | |
1150 | } | |
1151 | } | |
1152 | ||
1153 | if (!node) | |
1154 | return 0; | |
1155 | ||
1156 | new_node = alloc_backref_node(cache); | |
1157 | if (!new_node) | |
1158 | return -ENOMEM; | |
1159 | ||
1160 | new_node->bytenr = dest->node->start; | |
1161 | new_node->level = node->level; | |
1162 | new_node->lowest = node->lowest; | |
6848ad64 | 1163 | new_node->checked = 1; |
3fd0a558 YZ |
1164 | new_node->root = dest; |
1165 | ||
1166 | if (!node->lowest) { | |
1167 | list_for_each_entry(edge, &node->lower, list[UPPER]) { | |
1168 | new_edge = alloc_backref_edge(cache); | |
1169 | if (!new_edge) | |
1170 | goto fail; | |
1171 | ||
1172 | new_edge->node[UPPER] = new_node; | |
1173 | new_edge->node[LOWER] = edge->node[LOWER]; | |
1174 | list_add_tail(&new_edge->list[UPPER], | |
1175 | &new_node->lower); | |
1176 | } | |
1177 | } | |
1178 | ||
1179 | rb_node = tree_insert(&cache->rb_root, new_node->bytenr, | |
1180 | &new_node->rb_node); | |
1181 | BUG_ON(rb_node); | |
1182 | ||
1183 | if (!new_node->lowest) { | |
1184 | list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) { | |
1185 | list_add_tail(&new_edge->list[LOWER], | |
1186 | &new_edge->node[LOWER]->upper); | |
1187 | } | |
1188 | } | |
1189 | return 0; | |
1190 | fail: | |
1191 | while (!list_empty(&new_node->lower)) { | |
1192 | new_edge = list_entry(new_node->lower.next, | |
1193 | struct backref_edge, list[UPPER]); | |
1194 | list_del(&new_edge->list[UPPER]); | |
1195 | free_backref_edge(cache, new_edge); | |
1196 | } | |
1197 | free_backref_node(cache, new_node); | |
1198 | return -ENOMEM; | |
1199 | } | |
1200 | ||
5d4f98a2 YZ |
1201 | /* |
1202 | * helper to add 'address of tree root -> reloc tree' mapping | |
1203 | */ | |
1204 | static int __add_reloc_root(struct btrfs_root *root) | |
1205 | { | |
1206 | struct rb_node *rb_node; | |
1207 | struct mapping_node *node; | |
1208 | struct reloc_control *rc = root->fs_info->reloc_ctl; | |
1209 | ||
1210 | node = kmalloc(sizeof(*node), GFP_NOFS); | |
1211 | BUG_ON(!node); | |
1212 | ||
1213 | node->bytenr = root->node->start; | |
1214 | node->data = root; | |
1215 | ||
1216 | spin_lock(&rc->reloc_root_tree.lock); | |
1217 | rb_node = tree_insert(&rc->reloc_root_tree.rb_root, | |
1218 | node->bytenr, &node->rb_node); | |
1219 | spin_unlock(&rc->reloc_root_tree.lock); | |
1220 | BUG_ON(rb_node); | |
1221 | ||
1222 | list_add_tail(&root->root_list, &rc->reloc_roots); | |
1223 | return 0; | |
1224 | } | |
1225 | ||
1226 | /* | |
1227 | * helper to update/delete the 'address of tree root -> reloc tree' | |
1228 | * mapping | |
1229 | */ | |
1230 | static int __update_reloc_root(struct btrfs_root *root, int del) | |
1231 | { | |
1232 | struct rb_node *rb_node; | |
1233 | struct mapping_node *node = NULL; | |
1234 | struct reloc_control *rc = root->fs_info->reloc_ctl; | |
1235 | ||
1236 | spin_lock(&rc->reloc_root_tree.lock); | |
1237 | rb_node = tree_search(&rc->reloc_root_tree.rb_root, | |
1238 | root->commit_root->start); | |
1239 | if (rb_node) { | |
1240 | node = rb_entry(rb_node, struct mapping_node, rb_node); | |
1241 | rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); | |
1242 | } | |
1243 | spin_unlock(&rc->reloc_root_tree.lock); | |
1244 | ||
1245 | BUG_ON((struct btrfs_root *)node->data != root); | |
1246 | ||
1247 | if (!del) { | |
1248 | spin_lock(&rc->reloc_root_tree.lock); | |
1249 | node->bytenr = root->node->start; | |
1250 | rb_node = tree_insert(&rc->reloc_root_tree.rb_root, | |
1251 | node->bytenr, &node->rb_node); | |
1252 | spin_unlock(&rc->reloc_root_tree.lock); | |
1253 | BUG_ON(rb_node); | |
1254 | } else { | |
1255 | list_del_init(&root->root_list); | |
1256 | kfree(node); | |
1257 | } | |
1258 | return 0; | |
1259 | } | |
1260 | ||
3fd0a558 YZ |
1261 | static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans, |
1262 | struct btrfs_root *root, u64 objectid) | |
5d4f98a2 YZ |
1263 | { |
1264 | struct btrfs_root *reloc_root; | |
1265 | struct extent_buffer *eb; | |
1266 | struct btrfs_root_item *root_item; | |
1267 | struct btrfs_key root_key; | |
1268 | int ret; | |
1269 | ||
5d4f98a2 YZ |
1270 | root_item = kmalloc(sizeof(*root_item), GFP_NOFS); |
1271 | BUG_ON(!root_item); | |
1272 | ||
1273 | root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; | |
1274 | root_key.type = BTRFS_ROOT_ITEM_KEY; | |
3fd0a558 | 1275 | root_key.offset = objectid; |
5d4f98a2 | 1276 | |
3fd0a558 YZ |
1277 | if (root->root_key.objectid == objectid) { |
1278 | /* called by btrfs_init_reloc_root */ | |
1279 | ret = btrfs_copy_root(trans, root, root->commit_root, &eb, | |
1280 | BTRFS_TREE_RELOC_OBJECTID); | |
1281 | BUG_ON(ret); | |
1282 | ||
1283 | btrfs_set_root_last_snapshot(&root->root_item, | |
1284 | trans->transid - 1); | |
1285 | } else { | |
1286 | /* | |
1287 | * called by btrfs_reloc_post_snapshot_hook. | |
1288 | * the source tree is a reloc tree, all tree blocks | |
1289 | * modified after it was created have RELOC flag | |
1290 | * set in their headers. so it's OK to not update | |
1291 | * the 'last_snapshot'. | |
1292 | */ | |
1293 | ret = btrfs_copy_root(trans, root, root->node, &eb, | |
1294 | BTRFS_TREE_RELOC_OBJECTID); | |
1295 | BUG_ON(ret); | |
1296 | } | |
5d4f98a2 | 1297 | |
5d4f98a2 | 1298 | memcpy(root_item, &root->root_item, sizeof(*root_item)); |
5d4f98a2 YZ |
1299 | btrfs_set_root_bytenr(root_item, eb->start); |
1300 | btrfs_set_root_level(root_item, btrfs_header_level(eb)); | |
1301 | btrfs_set_root_generation(root_item, trans->transid); | |
3fd0a558 YZ |
1302 | |
1303 | if (root->root_key.objectid == objectid) { | |
1304 | btrfs_set_root_refs(root_item, 0); | |
1305 | memset(&root_item->drop_progress, 0, | |
1306 | sizeof(struct btrfs_disk_key)); | |
1307 | root_item->drop_level = 0; | |
1308 | } | |
5d4f98a2 YZ |
1309 | |
1310 | btrfs_tree_unlock(eb); | |
1311 | free_extent_buffer(eb); | |
1312 | ||
1313 | ret = btrfs_insert_root(trans, root->fs_info->tree_root, | |
1314 | &root_key, root_item); | |
1315 | BUG_ON(ret); | |
1316 | kfree(root_item); | |
1317 | ||
1318 | reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root, | |
1319 | &root_key); | |
1320 | BUG_ON(IS_ERR(reloc_root)); | |
1321 | reloc_root->last_trans = trans->transid; | |
3fd0a558 YZ |
1322 | return reloc_root; |
1323 | } | |
1324 | ||
1325 | /* | |
1326 | * create reloc tree for a given fs tree. reloc tree is just a | |
1327 | * snapshot of the fs tree with special root objectid. | |
1328 | */ | |
1329 | int btrfs_init_reloc_root(struct btrfs_trans_handle *trans, | |
1330 | struct btrfs_root *root) | |
1331 | { | |
1332 | struct btrfs_root *reloc_root; | |
1333 | struct reloc_control *rc = root->fs_info->reloc_ctl; | |
1334 | int clear_rsv = 0; | |
1335 | ||
1336 | if (root->reloc_root) { | |
1337 | reloc_root = root->reloc_root; | |
1338 | reloc_root->last_trans = trans->transid; | |
1339 | return 0; | |
1340 | } | |
1341 | ||
1342 | if (!rc || !rc->create_reloc_tree || | |
1343 | root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) | |
1344 | return 0; | |
1345 | ||
1346 | if (!trans->block_rsv) { | |
1347 | trans->block_rsv = rc->block_rsv; | |
1348 | clear_rsv = 1; | |
1349 | } | |
1350 | reloc_root = create_reloc_root(trans, root, root->root_key.objectid); | |
1351 | if (clear_rsv) | |
1352 | trans->block_rsv = NULL; | |
5d4f98a2 YZ |
1353 | |
1354 | __add_reloc_root(reloc_root); | |
1355 | root->reloc_root = reloc_root; | |
1356 | return 0; | |
1357 | } | |
1358 | ||
1359 | /* | |
1360 | * update root item of reloc tree | |
1361 | */ | |
1362 | int btrfs_update_reloc_root(struct btrfs_trans_handle *trans, | |
1363 | struct btrfs_root *root) | |
1364 | { | |
1365 | struct btrfs_root *reloc_root; | |
1366 | struct btrfs_root_item *root_item; | |
1367 | int del = 0; | |
1368 | int ret; | |
1369 | ||
1370 | if (!root->reloc_root) | |
1371 | return 0; | |
1372 | ||
1373 | reloc_root = root->reloc_root; | |
1374 | root_item = &reloc_root->root_item; | |
1375 | ||
3fd0a558 YZ |
1376 | if (root->fs_info->reloc_ctl->merge_reloc_tree && |
1377 | btrfs_root_refs(root_item) == 0) { | |
5d4f98a2 YZ |
1378 | root->reloc_root = NULL; |
1379 | del = 1; | |
1380 | } | |
1381 | ||
1382 | __update_reloc_root(reloc_root, del); | |
1383 | ||
1384 | if (reloc_root->commit_root != reloc_root->node) { | |
1385 | btrfs_set_root_node(root_item, reloc_root->node); | |
1386 | free_extent_buffer(reloc_root->commit_root); | |
1387 | reloc_root->commit_root = btrfs_root_node(reloc_root); | |
1388 | } | |
1389 | ||
1390 | ret = btrfs_update_root(trans, root->fs_info->tree_root, | |
1391 | &reloc_root->root_key, root_item); | |
1392 | BUG_ON(ret); | |
1393 | return 0; | |
1394 | } | |
1395 | ||
1396 | /* | |
1397 | * helper to find first cached inode with inode number >= objectid | |
1398 | * in a subvolume | |
1399 | */ | |
1400 | static struct inode *find_next_inode(struct btrfs_root *root, u64 objectid) | |
1401 | { | |
1402 | struct rb_node *node; | |
1403 | struct rb_node *prev; | |
1404 | struct btrfs_inode *entry; | |
1405 | struct inode *inode; | |
1406 | ||
1407 | spin_lock(&root->inode_lock); | |
1408 | again: | |
1409 | node = root->inode_tree.rb_node; | |
1410 | prev = NULL; | |
1411 | while (node) { | |
1412 | prev = node; | |
1413 | entry = rb_entry(node, struct btrfs_inode, rb_node); | |
1414 | ||
33345d01 | 1415 | if (objectid < btrfs_ino(&entry->vfs_inode)) |
5d4f98a2 | 1416 | node = node->rb_left; |
33345d01 | 1417 | else if (objectid > btrfs_ino(&entry->vfs_inode)) |
5d4f98a2 YZ |
1418 | node = node->rb_right; |
1419 | else | |
1420 | break; | |
1421 | } | |
1422 | if (!node) { | |
1423 | while (prev) { | |
1424 | entry = rb_entry(prev, struct btrfs_inode, rb_node); | |
33345d01 | 1425 | if (objectid <= btrfs_ino(&entry->vfs_inode)) { |
5d4f98a2 YZ |
1426 | node = prev; |
1427 | break; | |
1428 | } | |
1429 | prev = rb_next(prev); | |
1430 | } | |
1431 | } | |
1432 | while (node) { | |
1433 | entry = rb_entry(node, struct btrfs_inode, rb_node); | |
1434 | inode = igrab(&entry->vfs_inode); | |
1435 | if (inode) { | |
1436 | spin_unlock(&root->inode_lock); | |
1437 | return inode; | |
1438 | } | |
1439 | ||
33345d01 | 1440 | objectid = btrfs_ino(&entry->vfs_inode) + 1; |
5d4f98a2 YZ |
1441 | if (cond_resched_lock(&root->inode_lock)) |
1442 | goto again; | |
1443 | ||
1444 | node = rb_next(node); | |
1445 | } | |
1446 | spin_unlock(&root->inode_lock); | |
1447 | return NULL; | |
1448 | } | |
1449 | ||
1450 | static int in_block_group(u64 bytenr, | |
1451 | struct btrfs_block_group_cache *block_group) | |
1452 | { | |
1453 | if (bytenr >= block_group->key.objectid && | |
1454 | bytenr < block_group->key.objectid + block_group->key.offset) | |
1455 | return 1; | |
1456 | return 0; | |
1457 | } | |
1458 | ||
1459 | /* | |
1460 | * get new location of data | |
1461 | */ | |
1462 | static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr, | |
1463 | u64 bytenr, u64 num_bytes) | |
1464 | { | |
1465 | struct btrfs_root *root = BTRFS_I(reloc_inode)->root; | |
1466 | struct btrfs_path *path; | |
1467 | struct btrfs_file_extent_item *fi; | |
1468 | struct extent_buffer *leaf; | |
1469 | int ret; | |
1470 | ||
1471 | path = btrfs_alloc_path(); | |
1472 | if (!path) | |
1473 | return -ENOMEM; | |
1474 | ||
1475 | bytenr -= BTRFS_I(reloc_inode)->index_cnt; | |
33345d01 | 1476 | ret = btrfs_lookup_file_extent(NULL, root, path, btrfs_ino(reloc_inode), |
5d4f98a2 YZ |
1477 | bytenr, 0); |
1478 | if (ret < 0) | |
1479 | goto out; | |
1480 | if (ret > 0) { | |
1481 | ret = -ENOENT; | |
1482 | goto out; | |
1483 | } | |
1484 | ||
1485 | leaf = path->nodes[0]; | |
1486 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
1487 | struct btrfs_file_extent_item); | |
1488 | ||
1489 | BUG_ON(btrfs_file_extent_offset(leaf, fi) || | |
1490 | btrfs_file_extent_compression(leaf, fi) || | |
1491 | btrfs_file_extent_encryption(leaf, fi) || | |
1492 | btrfs_file_extent_other_encoding(leaf, fi)); | |
1493 | ||
1494 | if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) { | |
1495 | ret = 1; | |
1496 | goto out; | |
1497 | } | |
1498 | ||
3fd0a558 | 1499 | *new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); |
5d4f98a2 YZ |
1500 | ret = 0; |
1501 | out: | |
1502 | btrfs_free_path(path); | |
1503 | return ret; | |
1504 | } | |
1505 | ||
1506 | /* | |
1507 | * update file extent items in the tree leaf to point to | |
1508 | * the new locations. | |
1509 | */ | |
3fd0a558 YZ |
1510 | static noinline_for_stack |
1511 | int replace_file_extents(struct btrfs_trans_handle *trans, | |
1512 | struct reloc_control *rc, | |
1513 | struct btrfs_root *root, | |
1514 | struct extent_buffer *leaf) | |
5d4f98a2 YZ |
1515 | { |
1516 | struct btrfs_key key; | |
1517 | struct btrfs_file_extent_item *fi; | |
1518 | struct inode *inode = NULL; | |
5d4f98a2 YZ |
1519 | u64 parent; |
1520 | u64 bytenr; | |
3fd0a558 | 1521 | u64 new_bytenr = 0; |
5d4f98a2 YZ |
1522 | u64 num_bytes; |
1523 | u64 end; | |
1524 | u32 nritems; | |
1525 | u32 i; | |
1526 | int ret; | |
1527 | int first = 1; | |
1528 | int dirty = 0; | |
1529 | ||
1530 | if (rc->stage != UPDATE_DATA_PTRS) | |
1531 | return 0; | |
1532 | ||
1533 | /* reloc trees always use full backref */ | |
1534 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) | |
1535 | parent = leaf->start; | |
1536 | else | |
1537 | parent = 0; | |
1538 | ||
1539 | nritems = btrfs_header_nritems(leaf); | |
1540 | for (i = 0; i < nritems; i++) { | |
1541 | cond_resched(); | |
1542 | btrfs_item_key_to_cpu(leaf, &key, i); | |
1543 | if (key.type != BTRFS_EXTENT_DATA_KEY) | |
1544 | continue; | |
1545 | fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); | |
1546 | if (btrfs_file_extent_type(leaf, fi) == | |
1547 | BTRFS_FILE_EXTENT_INLINE) | |
1548 | continue; | |
1549 | bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
1550 | num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); | |
1551 | if (bytenr == 0) | |
1552 | continue; | |
1553 | if (!in_block_group(bytenr, rc->block_group)) | |
1554 | continue; | |
1555 | ||
1556 | /* | |
1557 | * if we are modifying block in fs tree, wait for readpage | |
1558 | * to complete and drop the extent cache | |
1559 | */ | |
1560 | if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { | |
5d4f98a2 YZ |
1561 | if (first) { |
1562 | inode = find_next_inode(root, key.objectid); | |
5d4f98a2 | 1563 | first = 0; |
33345d01 | 1564 | } else if (inode && btrfs_ino(inode) < key.objectid) { |
3fd0a558 | 1565 | btrfs_add_delayed_iput(inode); |
5d4f98a2 | 1566 | inode = find_next_inode(root, key.objectid); |
5d4f98a2 | 1567 | } |
33345d01 | 1568 | if (inode && btrfs_ino(inode) == key.objectid) { |
5d4f98a2 YZ |
1569 | end = key.offset + |
1570 | btrfs_file_extent_num_bytes(leaf, fi); | |
1571 | WARN_ON(!IS_ALIGNED(key.offset, | |
1572 | root->sectorsize)); | |
1573 | WARN_ON(!IS_ALIGNED(end, root->sectorsize)); | |
1574 | end--; | |
1575 | ret = try_lock_extent(&BTRFS_I(inode)->io_tree, | |
1576 | key.offset, end, | |
1577 | GFP_NOFS); | |
1578 | if (!ret) | |
1579 | continue; | |
1580 | ||
1581 | btrfs_drop_extent_cache(inode, key.offset, end, | |
1582 | 1); | |
1583 | unlock_extent(&BTRFS_I(inode)->io_tree, | |
1584 | key.offset, end, GFP_NOFS); | |
1585 | } | |
1586 | } | |
1587 | ||
1588 | ret = get_new_location(rc->data_inode, &new_bytenr, | |
1589 | bytenr, num_bytes); | |
3fd0a558 YZ |
1590 | if (ret > 0) { |
1591 | WARN_ON(1); | |
5d4f98a2 | 1592 | continue; |
3fd0a558 | 1593 | } |
5d4f98a2 YZ |
1594 | BUG_ON(ret < 0); |
1595 | ||
1596 | btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr); | |
1597 | dirty = 1; | |
1598 | ||
1599 | key.offset -= btrfs_file_extent_offset(leaf, fi); | |
1600 | ret = btrfs_inc_extent_ref(trans, root, new_bytenr, | |
1601 | num_bytes, parent, | |
1602 | btrfs_header_owner(leaf), | |
1603 | key.objectid, key.offset); | |
1604 | BUG_ON(ret); | |
1605 | ||
1606 | ret = btrfs_free_extent(trans, root, bytenr, num_bytes, | |
1607 | parent, btrfs_header_owner(leaf), | |
1608 | key.objectid, key.offset); | |
1609 | BUG_ON(ret); | |
1610 | } | |
1611 | if (dirty) | |
1612 | btrfs_mark_buffer_dirty(leaf); | |
3fd0a558 YZ |
1613 | if (inode) |
1614 | btrfs_add_delayed_iput(inode); | |
5d4f98a2 YZ |
1615 | return 0; |
1616 | } | |
1617 | ||
1618 | static noinline_for_stack | |
1619 | int memcmp_node_keys(struct extent_buffer *eb, int slot, | |
1620 | struct btrfs_path *path, int level) | |
1621 | { | |
1622 | struct btrfs_disk_key key1; | |
1623 | struct btrfs_disk_key key2; | |
1624 | btrfs_node_key(eb, &key1, slot); | |
1625 | btrfs_node_key(path->nodes[level], &key2, path->slots[level]); | |
1626 | return memcmp(&key1, &key2, sizeof(key1)); | |
1627 | } | |
1628 | ||
1629 | /* | |
1630 | * try to replace tree blocks in fs tree with the new blocks | |
1631 | * in reloc tree. tree blocks haven't been modified since the | |
1632 | * reloc tree was create can be replaced. | |
1633 | * | |
1634 | * if a block was replaced, level of the block + 1 is returned. | |
1635 | * if no block got replaced, 0 is returned. if there are other | |
1636 | * errors, a negative error number is returned. | |
1637 | */ | |
3fd0a558 YZ |
1638 | static noinline_for_stack |
1639 | int replace_path(struct btrfs_trans_handle *trans, | |
1640 | struct btrfs_root *dest, struct btrfs_root *src, | |
1641 | struct btrfs_path *path, struct btrfs_key *next_key, | |
1642 | int lowest_level, int max_level) | |
5d4f98a2 YZ |
1643 | { |
1644 | struct extent_buffer *eb; | |
1645 | struct extent_buffer *parent; | |
1646 | struct btrfs_key key; | |
1647 | u64 old_bytenr; | |
1648 | u64 new_bytenr; | |
1649 | u64 old_ptr_gen; | |
1650 | u64 new_ptr_gen; | |
1651 | u64 last_snapshot; | |
1652 | u32 blocksize; | |
3fd0a558 | 1653 | int cow = 0; |
5d4f98a2 YZ |
1654 | int level; |
1655 | int ret; | |
1656 | int slot; | |
1657 | ||
1658 | BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); | |
1659 | BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID); | |
5d4f98a2 YZ |
1660 | |
1661 | last_snapshot = btrfs_root_last_snapshot(&src->root_item); | |
3fd0a558 | 1662 | again: |
5d4f98a2 YZ |
1663 | slot = path->slots[lowest_level]; |
1664 | btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot); | |
1665 | ||
1666 | eb = btrfs_lock_root_node(dest); | |
1667 | btrfs_set_lock_blocking(eb); | |
1668 | level = btrfs_header_level(eb); | |
1669 | ||
1670 | if (level < lowest_level) { | |
1671 | btrfs_tree_unlock(eb); | |
1672 | free_extent_buffer(eb); | |
1673 | return 0; | |
1674 | } | |
1675 | ||
3fd0a558 YZ |
1676 | if (cow) { |
1677 | ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb); | |
1678 | BUG_ON(ret); | |
1679 | } | |
5d4f98a2 YZ |
1680 | btrfs_set_lock_blocking(eb); |
1681 | ||
1682 | if (next_key) { | |
1683 | next_key->objectid = (u64)-1; | |
1684 | next_key->type = (u8)-1; | |
1685 | next_key->offset = (u64)-1; | |
1686 | } | |
1687 | ||
1688 | parent = eb; | |
1689 | while (1) { | |
1690 | level = btrfs_header_level(parent); | |
1691 | BUG_ON(level < lowest_level); | |
1692 | ||
1693 | ret = btrfs_bin_search(parent, &key, level, &slot); | |
1694 | if (ret && slot > 0) | |
1695 | slot--; | |
1696 | ||
1697 | if (next_key && slot + 1 < btrfs_header_nritems(parent)) | |
1698 | btrfs_node_key_to_cpu(parent, next_key, slot + 1); | |
1699 | ||
1700 | old_bytenr = btrfs_node_blockptr(parent, slot); | |
1701 | blocksize = btrfs_level_size(dest, level - 1); | |
1702 | old_ptr_gen = btrfs_node_ptr_generation(parent, slot); | |
1703 | ||
1704 | if (level <= max_level) { | |
1705 | eb = path->nodes[level]; | |
1706 | new_bytenr = btrfs_node_blockptr(eb, | |
1707 | path->slots[level]); | |
1708 | new_ptr_gen = btrfs_node_ptr_generation(eb, | |
1709 | path->slots[level]); | |
1710 | } else { | |
1711 | new_bytenr = 0; | |
1712 | new_ptr_gen = 0; | |
1713 | } | |
1714 | ||
1715 | if (new_bytenr > 0 && new_bytenr == old_bytenr) { | |
1716 | WARN_ON(1); | |
1717 | ret = level; | |
1718 | break; | |
1719 | } | |
1720 | ||
1721 | if (new_bytenr == 0 || old_ptr_gen > last_snapshot || | |
1722 | memcmp_node_keys(parent, slot, path, level)) { | |
3fd0a558 | 1723 | if (level <= lowest_level) { |
5d4f98a2 YZ |
1724 | ret = 0; |
1725 | break; | |
1726 | } | |
1727 | ||
1728 | eb = read_tree_block(dest, old_bytenr, blocksize, | |
1729 | old_ptr_gen); | |
97d9a8a4 | 1730 | BUG_ON(!eb); |
5d4f98a2 | 1731 | btrfs_tree_lock(eb); |
3fd0a558 YZ |
1732 | if (cow) { |
1733 | ret = btrfs_cow_block(trans, dest, eb, parent, | |
1734 | slot, &eb); | |
1735 | BUG_ON(ret); | |
5d4f98a2 | 1736 | } |
3fd0a558 | 1737 | btrfs_set_lock_blocking(eb); |
5d4f98a2 YZ |
1738 | |
1739 | btrfs_tree_unlock(parent); | |
1740 | free_extent_buffer(parent); | |
1741 | ||
1742 | parent = eb; | |
1743 | continue; | |
1744 | } | |
1745 | ||
3fd0a558 YZ |
1746 | if (!cow) { |
1747 | btrfs_tree_unlock(parent); | |
1748 | free_extent_buffer(parent); | |
1749 | cow = 1; | |
1750 | goto again; | |
1751 | } | |
1752 | ||
5d4f98a2 YZ |
1753 | btrfs_node_key_to_cpu(path->nodes[level], &key, |
1754 | path->slots[level]); | |
b3b4aa74 | 1755 | btrfs_release_path(path); |
5d4f98a2 YZ |
1756 | |
1757 | path->lowest_level = level; | |
1758 | ret = btrfs_search_slot(trans, src, &key, path, 0, 1); | |
1759 | path->lowest_level = 0; | |
1760 | BUG_ON(ret); | |
1761 | ||
1762 | /* | |
1763 | * swap blocks in fs tree and reloc tree. | |
1764 | */ | |
1765 | btrfs_set_node_blockptr(parent, slot, new_bytenr); | |
1766 | btrfs_set_node_ptr_generation(parent, slot, new_ptr_gen); | |
1767 | btrfs_mark_buffer_dirty(parent); | |
1768 | ||
1769 | btrfs_set_node_blockptr(path->nodes[level], | |
1770 | path->slots[level], old_bytenr); | |
1771 | btrfs_set_node_ptr_generation(path->nodes[level], | |
1772 | path->slots[level], old_ptr_gen); | |
1773 | btrfs_mark_buffer_dirty(path->nodes[level]); | |
1774 | ||
1775 | ret = btrfs_inc_extent_ref(trans, src, old_bytenr, blocksize, | |
1776 | path->nodes[level]->start, | |
1777 | src->root_key.objectid, level - 1, 0); | |
1778 | BUG_ON(ret); | |
1779 | ret = btrfs_inc_extent_ref(trans, dest, new_bytenr, blocksize, | |
1780 | 0, dest->root_key.objectid, level - 1, | |
1781 | 0); | |
1782 | BUG_ON(ret); | |
1783 | ||
1784 | ret = btrfs_free_extent(trans, src, new_bytenr, blocksize, | |
1785 | path->nodes[level]->start, | |
1786 | src->root_key.objectid, level - 1, 0); | |
1787 | BUG_ON(ret); | |
1788 | ||
1789 | ret = btrfs_free_extent(trans, dest, old_bytenr, blocksize, | |
1790 | 0, dest->root_key.objectid, level - 1, | |
1791 | 0); | |
1792 | BUG_ON(ret); | |
1793 | ||
1794 | btrfs_unlock_up_safe(path, 0); | |
1795 | ||
1796 | ret = level; | |
1797 | break; | |
1798 | } | |
1799 | btrfs_tree_unlock(parent); | |
1800 | free_extent_buffer(parent); | |
1801 | return ret; | |
1802 | } | |
1803 | ||
1804 | /* | |
1805 | * helper to find next relocated block in reloc tree | |
1806 | */ | |
1807 | static noinline_for_stack | |
1808 | int walk_up_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, | |
1809 | int *level) | |
1810 | { | |
1811 | struct extent_buffer *eb; | |
1812 | int i; | |
1813 | u64 last_snapshot; | |
1814 | u32 nritems; | |
1815 | ||
1816 | last_snapshot = btrfs_root_last_snapshot(&root->root_item); | |
1817 | ||
1818 | for (i = 0; i < *level; i++) { | |
1819 | free_extent_buffer(path->nodes[i]); | |
1820 | path->nodes[i] = NULL; | |
1821 | } | |
1822 | ||
1823 | for (i = *level; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) { | |
1824 | eb = path->nodes[i]; | |
1825 | nritems = btrfs_header_nritems(eb); | |
1826 | while (path->slots[i] + 1 < nritems) { | |
1827 | path->slots[i]++; | |
1828 | if (btrfs_node_ptr_generation(eb, path->slots[i]) <= | |
1829 | last_snapshot) | |
1830 | continue; | |
1831 | ||
1832 | *level = i; | |
1833 | return 0; | |
1834 | } | |
1835 | free_extent_buffer(path->nodes[i]); | |
1836 | path->nodes[i] = NULL; | |
1837 | } | |
1838 | return 1; | |
1839 | } | |
1840 | ||
1841 | /* | |
1842 | * walk down reloc tree to find relocated block of lowest level | |
1843 | */ | |
1844 | static noinline_for_stack | |
1845 | int walk_down_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, | |
1846 | int *level) | |
1847 | { | |
1848 | struct extent_buffer *eb = NULL; | |
1849 | int i; | |
1850 | u64 bytenr; | |
1851 | u64 ptr_gen = 0; | |
1852 | u64 last_snapshot; | |
1853 | u32 blocksize; | |
1854 | u32 nritems; | |
1855 | ||
1856 | last_snapshot = btrfs_root_last_snapshot(&root->root_item); | |
1857 | ||
1858 | for (i = *level; i > 0; i--) { | |
1859 | eb = path->nodes[i]; | |
1860 | nritems = btrfs_header_nritems(eb); | |
1861 | while (path->slots[i] < nritems) { | |
1862 | ptr_gen = btrfs_node_ptr_generation(eb, path->slots[i]); | |
1863 | if (ptr_gen > last_snapshot) | |
1864 | break; | |
1865 | path->slots[i]++; | |
1866 | } | |
1867 | if (path->slots[i] >= nritems) { | |
1868 | if (i == *level) | |
1869 | break; | |
1870 | *level = i + 1; | |
1871 | return 0; | |
1872 | } | |
1873 | if (i == 1) { | |
1874 | *level = i; | |
1875 | return 0; | |
1876 | } | |
1877 | ||
1878 | bytenr = btrfs_node_blockptr(eb, path->slots[i]); | |
1879 | blocksize = btrfs_level_size(root, i - 1); | |
1880 | eb = read_tree_block(root, bytenr, blocksize, ptr_gen); | |
1881 | BUG_ON(btrfs_header_level(eb) != i - 1); | |
1882 | path->nodes[i - 1] = eb; | |
1883 | path->slots[i - 1] = 0; | |
1884 | } | |
1885 | return 1; | |
1886 | } | |
1887 | ||
1888 | /* | |
1889 | * invalidate extent cache for file extents whose key in range of | |
1890 | * [min_key, max_key) | |
1891 | */ | |
1892 | static int invalidate_extent_cache(struct btrfs_root *root, | |
1893 | struct btrfs_key *min_key, | |
1894 | struct btrfs_key *max_key) | |
1895 | { | |
1896 | struct inode *inode = NULL; | |
1897 | u64 objectid; | |
1898 | u64 start, end; | |
33345d01 | 1899 | u64 ino; |
5d4f98a2 YZ |
1900 | |
1901 | objectid = min_key->objectid; | |
1902 | while (1) { | |
1903 | cond_resched(); | |
1904 | iput(inode); | |
1905 | ||
1906 | if (objectid > max_key->objectid) | |
1907 | break; | |
1908 | ||
1909 | inode = find_next_inode(root, objectid); | |
1910 | if (!inode) | |
1911 | break; | |
33345d01 | 1912 | ino = btrfs_ino(inode); |
5d4f98a2 | 1913 | |
33345d01 | 1914 | if (ino > max_key->objectid) { |
5d4f98a2 YZ |
1915 | iput(inode); |
1916 | break; | |
1917 | } | |
1918 | ||
33345d01 | 1919 | objectid = ino + 1; |
5d4f98a2 YZ |
1920 | if (!S_ISREG(inode->i_mode)) |
1921 | continue; | |
1922 | ||
33345d01 | 1923 | if (unlikely(min_key->objectid == ino)) { |
5d4f98a2 YZ |
1924 | if (min_key->type > BTRFS_EXTENT_DATA_KEY) |
1925 | continue; | |
1926 | if (min_key->type < BTRFS_EXTENT_DATA_KEY) | |
1927 | start = 0; | |
1928 | else { | |
1929 | start = min_key->offset; | |
1930 | WARN_ON(!IS_ALIGNED(start, root->sectorsize)); | |
1931 | } | |
1932 | } else { | |
1933 | start = 0; | |
1934 | } | |
1935 | ||
33345d01 | 1936 | if (unlikely(max_key->objectid == ino)) { |
5d4f98a2 YZ |
1937 | if (max_key->type < BTRFS_EXTENT_DATA_KEY) |
1938 | continue; | |
1939 | if (max_key->type > BTRFS_EXTENT_DATA_KEY) { | |
1940 | end = (u64)-1; | |
1941 | } else { | |
1942 | if (max_key->offset == 0) | |
1943 | continue; | |
1944 | end = max_key->offset; | |
1945 | WARN_ON(!IS_ALIGNED(end, root->sectorsize)); | |
1946 | end--; | |
1947 | } | |
1948 | } else { | |
1949 | end = (u64)-1; | |
1950 | } | |
1951 | ||
1952 | /* the lock_extent waits for readpage to complete */ | |
1953 | lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
1954 | btrfs_drop_extent_cache(inode, start, end, 1); | |
1955 | unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
1956 | } | |
1957 | return 0; | |
1958 | } | |
1959 | ||
1960 | static int find_next_key(struct btrfs_path *path, int level, | |
1961 | struct btrfs_key *key) | |
1962 | ||
1963 | { | |
1964 | while (level < BTRFS_MAX_LEVEL) { | |
1965 | if (!path->nodes[level]) | |
1966 | break; | |
1967 | if (path->slots[level] + 1 < | |
1968 | btrfs_header_nritems(path->nodes[level])) { | |
1969 | btrfs_node_key_to_cpu(path->nodes[level], key, | |
1970 | path->slots[level] + 1); | |
1971 | return 0; | |
1972 | } | |
1973 | level++; | |
1974 | } | |
1975 | return 1; | |
1976 | } | |
1977 | ||
1978 | /* | |
1979 | * merge the relocated tree blocks in reloc tree with corresponding | |
1980 | * fs tree. | |
1981 | */ | |
1982 | static noinline_for_stack int merge_reloc_root(struct reloc_control *rc, | |
1983 | struct btrfs_root *root) | |
1984 | { | |
1985 | LIST_HEAD(inode_list); | |
1986 | struct btrfs_key key; | |
1987 | struct btrfs_key next_key; | |
1988 | struct btrfs_trans_handle *trans; | |
1989 | struct btrfs_root *reloc_root; | |
1990 | struct btrfs_root_item *root_item; | |
1991 | struct btrfs_path *path; | |
3fd0a558 | 1992 | struct extent_buffer *leaf; |
5d4f98a2 YZ |
1993 | unsigned long nr; |
1994 | int level; | |
1995 | int max_level; | |
1996 | int replaced = 0; | |
1997 | int ret; | |
1998 | int err = 0; | |
3fd0a558 | 1999 | u32 min_reserved; |
5d4f98a2 YZ |
2000 | |
2001 | path = btrfs_alloc_path(); | |
2002 | if (!path) | |
2003 | return -ENOMEM; | |
026fd317 | 2004 | path->reada = 1; |
5d4f98a2 YZ |
2005 | |
2006 | reloc_root = root->reloc_root; | |
2007 | root_item = &reloc_root->root_item; | |
2008 | ||
2009 | if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { | |
2010 | level = btrfs_root_level(root_item); | |
2011 | extent_buffer_get(reloc_root->node); | |
2012 | path->nodes[level] = reloc_root->node; | |
2013 | path->slots[level] = 0; | |
2014 | } else { | |
2015 | btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); | |
2016 | ||
2017 | level = root_item->drop_level; | |
2018 | BUG_ON(level == 0); | |
2019 | path->lowest_level = level; | |
2020 | ret = btrfs_search_slot(NULL, reloc_root, &key, path, 0, 0); | |
33c66f43 | 2021 | path->lowest_level = 0; |
5d4f98a2 YZ |
2022 | if (ret < 0) { |
2023 | btrfs_free_path(path); | |
2024 | return ret; | |
2025 | } | |
2026 | ||
2027 | btrfs_node_key_to_cpu(path->nodes[level], &next_key, | |
2028 | path->slots[level]); | |
2029 | WARN_ON(memcmp(&key, &next_key, sizeof(key))); | |
2030 | ||
2031 | btrfs_unlock_up_safe(path, 0); | |
2032 | } | |
2033 | ||
3fd0a558 YZ |
2034 | min_reserved = root->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; |
2035 | memset(&next_key, 0, sizeof(next_key)); | |
5d4f98a2 | 2036 | |
3fd0a558 YZ |
2037 | while (1) { |
2038 | trans = btrfs_start_transaction(root, 0); | |
98d5dc13 | 2039 | BUG_ON(IS_ERR(trans)); |
3fd0a558 | 2040 | trans->block_rsv = rc->block_rsv; |
5d4f98a2 | 2041 | |
3fd0a558 YZ |
2042 | ret = btrfs_block_rsv_check(trans, root, rc->block_rsv, |
2043 | min_reserved, 0); | |
2044 | if (ret) { | |
2045 | BUG_ON(ret != -EAGAIN); | |
2046 | ret = btrfs_commit_transaction(trans, root); | |
2047 | BUG_ON(ret); | |
2048 | continue; | |
5d4f98a2 YZ |
2049 | } |
2050 | ||
5d4f98a2 | 2051 | replaced = 0; |
5d4f98a2 YZ |
2052 | max_level = level; |
2053 | ||
2054 | ret = walk_down_reloc_tree(reloc_root, path, &level); | |
2055 | if (ret < 0) { | |
2056 | err = ret; | |
2057 | goto out; | |
2058 | } | |
2059 | if (ret > 0) | |
2060 | break; | |
2061 | ||
2062 | if (!find_next_key(path, level, &key) && | |
2063 | btrfs_comp_cpu_keys(&next_key, &key) >= 0) { | |
2064 | ret = 0; | |
5d4f98a2 | 2065 | } else { |
3fd0a558 YZ |
2066 | ret = replace_path(trans, root, reloc_root, path, |
2067 | &next_key, level, max_level); | |
5d4f98a2 YZ |
2068 | } |
2069 | if (ret < 0) { | |
2070 | err = ret; | |
2071 | goto out; | |
2072 | } | |
2073 | ||
2074 | if (ret > 0) { | |
2075 | level = ret; | |
2076 | btrfs_node_key_to_cpu(path->nodes[level], &key, | |
2077 | path->slots[level]); | |
2078 | replaced = 1; | |
5d4f98a2 YZ |
2079 | } |
2080 | ||
2081 | ret = walk_up_reloc_tree(reloc_root, path, &level); | |
2082 | if (ret > 0) | |
2083 | break; | |
2084 | ||
2085 | BUG_ON(level == 0); | |
2086 | /* | |
2087 | * save the merging progress in the drop_progress. | |
2088 | * this is OK since root refs == 1 in this case. | |
2089 | */ | |
2090 | btrfs_node_key(path->nodes[level], &root_item->drop_progress, | |
2091 | path->slots[level]); | |
2092 | root_item->drop_level = level; | |
2093 | ||
2094 | nr = trans->blocks_used; | |
3fd0a558 | 2095 | btrfs_end_transaction_throttle(trans, root); |
5d4f98a2 YZ |
2096 | |
2097 | btrfs_btree_balance_dirty(root, nr); | |
2098 | ||
2099 | if (replaced && rc->stage == UPDATE_DATA_PTRS) | |
2100 | invalidate_extent_cache(root, &key, &next_key); | |
2101 | } | |
2102 | ||
2103 | /* | |
2104 | * handle the case only one block in the fs tree need to be | |
2105 | * relocated and the block is tree root. | |
2106 | */ | |
2107 | leaf = btrfs_lock_root_node(root); | |
2108 | ret = btrfs_cow_block(trans, root, leaf, NULL, 0, &leaf); | |
2109 | btrfs_tree_unlock(leaf); | |
2110 | free_extent_buffer(leaf); | |
2111 | if (ret < 0) | |
2112 | err = ret; | |
2113 | out: | |
2114 | btrfs_free_path(path); | |
2115 | ||
2116 | if (err == 0) { | |
2117 | memset(&root_item->drop_progress, 0, | |
2118 | sizeof(root_item->drop_progress)); | |
2119 | root_item->drop_level = 0; | |
2120 | btrfs_set_root_refs(root_item, 0); | |
3fd0a558 | 2121 | btrfs_update_reloc_root(trans, root); |
5d4f98a2 YZ |
2122 | } |
2123 | ||
2124 | nr = trans->blocks_used; | |
3fd0a558 | 2125 | btrfs_end_transaction_throttle(trans, root); |
5d4f98a2 YZ |
2126 | |
2127 | btrfs_btree_balance_dirty(root, nr); | |
2128 | ||
5d4f98a2 YZ |
2129 | if (replaced && rc->stage == UPDATE_DATA_PTRS) |
2130 | invalidate_extent_cache(root, &key, &next_key); | |
2131 | ||
2132 | return err; | |
2133 | } | |
2134 | ||
3fd0a558 YZ |
2135 | static noinline_for_stack |
2136 | int prepare_to_merge(struct reloc_control *rc, int err) | |
5d4f98a2 | 2137 | { |
3fd0a558 | 2138 | struct btrfs_root *root = rc->extent_root; |
5d4f98a2 | 2139 | struct btrfs_root *reloc_root; |
3fd0a558 YZ |
2140 | struct btrfs_trans_handle *trans; |
2141 | LIST_HEAD(reloc_roots); | |
2142 | u64 num_bytes = 0; | |
2143 | int ret; | |
3fd0a558 | 2144 | |
a4abeea4 | 2145 | spin_lock(&root->fs_info->trans_lock); |
3fd0a558 YZ |
2146 | rc->merging_rsv_size += root->nodesize * (BTRFS_MAX_LEVEL - 1) * 2; |
2147 | rc->merging_rsv_size += rc->nodes_relocated * 2; | |
a4abeea4 | 2148 | spin_unlock(&root->fs_info->trans_lock); |
3fd0a558 YZ |
2149 | again: |
2150 | if (!err) { | |
2151 | num_bytes = rc->merging_rsv_size; | |
2152 | ret = btrfs_block_rsv_add(NULL, root, rc->block_rsv, | |
8bb8ab2e | 2153 | num_bytes); |
3fd0a558 YZ |
2154 | if (ret) |
2155 | err = ret; | |
2156 | } | |
2157 | ||
7a7eaa40 | 2158 | trans = btrfs_join_transaction(rc->extent_root); |
3612b495 TI |
2159 | if (IS_ERR(trans)) { |
2160 | if (!err) | |
2161 | btrfs_block_rsv_release(rc->extent_root, | |
2162 | rc->block_rsv, num_bytes); | |
2163 | return PTR_ERR(trans); | |
2164 | } | |
3fd0a558 YZ |
2165 | |
2166 | if (!err) { | |
2167 | if (num_bytes != rc->merging_rsv_size) { | |
2168 | btrfs_end_transaction(trans, rc->extent_root); | |
2169 | btrfs_block_rsv_release(rc->extent_root, | |
2170 | rc->block_rsv, num_bytes); | |
3fd0a558 YZ |
2171 | goto again; |
2172 | } | |
2173 | } | |
5d4f98a2 | 2174 | |
3fd0a558 YZ |
2175 | rc->merge_reloc_tree = 1; |
2176 | ||
2177 | while (!list_empty(&rc->reloc_roots)) { | |
2178 | reloc_root = list_entry(rc->reloc_roots.next, | |
2179 | struct btrfs_root, root_list); | |
2180 | list_del_init(&reloc_root->root_list); | |
5d4f98a2 | 2181 | |
5d4f98a2 YZ |
2182 | root = read_fs_root(reloc_root->fs_info, |
2183 | reloc_root->root_key.offset); | |
2184 | BUG_ON(IS_ERR(root)); | |
2185 | BUG_ON(root->reloc_root != reloc_root); | |
2186 | ||
3fd0a558 YZ |
2187 | /* |
2188 | * set reference count to 1, so btrfs_recover_relocation | |
2189 | * knows it should resumes merging | |
2190 | */ | |
2191 | if (!err) | |
2192 | btrfs_set_root_refs(&reloc_root->root_item, 1); | |
5d4f98a2 | 2193 | btrfs_update_reloc_root(trans, root); |
5d4f98a2 | 2194 | |
3fd0a558 YZ |
2195 | list_add(&reloc_root->root_list, &reloc_roots); |
2196 | } | |
5d4f98a2 | 2197 | |
3fd0a558 | 2198 | list_splice(&reloc_roots, &rc->reloc_roots); |
5d4f98a2 | 2199 | |
3fd0a558 YZ |
2200 | if (!err) |
2201 | btrfs_commit_transaction(trans, rc->extent_root); | |
2202 | else | |
2203 | btrfs_end_transaction(trans, rc->extent_root); | |
2204 | return err; | |
5d4f98a2 YZ |
2205 | } |
2206 | ||
3fd0a558 YZ |
2207 | static noinline_for_stack |
2208 | int merge_reloc_roots(struct reloc_control *rc) | |
5d4f98a2 | 2209 | { |
5d4f98a2 | 2210 | struct btrfs_root *root; |
3fd0a558 YZ |
2211 | struct btrfs_root *reloc_root; |
2212 | LIST_HEAD(reloc_roots); | |
2213 | int found = 0; | |
2214 | int ret; | |
2215 | again: | |
2216 | root = rc->extent_root; | |
a4abeea4 | 2217 | spin_lock(&root->fs_info->trans_lock); |
3fd0a558 | 2218 | list_splice_init(&rc->reloc_roots, &reloc_roots); |
a4abeea4 | 2219 | spin_unlock(&root->fs_info->trans_lock); |
5d4f98a2 | 2220 | |
3fd0a558 YZ |
2221 | while (!list_empty(&reloc_roots)) { |
2222 | found = 1; | |
2223 | reloc_root = list_entry(reloc_roots.next, | |
2224 | struct btrfs_root, root_list); | |
5d4f98a2 | 2225 | |
3fd0a558 YZ |
2226 | if (btrfs_root_refs(&reloc_root->root_item) > 0) { |
2227 | root = read_fs_root(reloc_root->fs_info, | |
2228 | reloc_root->root_key.offset); | |
2229 | BUG_ON(IS_ERR(root)); | |
2230 | BUG_ON(root->reloc_root != reloc_root); | |
5d4f98a2 | 2231 | |
3fd0a558 YZ |
2232 | ret = merge_reloc_root(rc, root); |
2233 | BUG_ON(ret); | |
2234 | } else { | |
2235 | list_del_init(&reloc_root->root_list); | |
2236 | } | |
2237 | btrfs_drop_snapshot(reloc_root, rc->block_rsv, 0); | |
5d4f98a2 YZ |
2238 | } |
2239 | ||
3fd0a558 YZ |
2240 | if (found) { |
2241 | found = 0; | |
2242 | goto again; | |
2243 | } | |
5d4f98a2 YZ |
2244 | BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root)); |
2245 | return 0; | |
2246 | } | |
2247 | ||
2248 | static void free_block_list(struct rb_root *blocks) | |
2249 | { | |
2250 | struct tree_block *block; | |
2251 | struct rb_node *rb_node; | |
2252 | while ((rb_node = rb_first(blocks))) { | |
2253 | block = rb_entry(rb_node, struct tree_block, rb_node); | |
2254 | rb_erase(rb_node, blocks); | |
2255 | kfree(block); | |
2256 | } | |
2257 | } | |
2258 | ||
2259 | static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans, | |
2260 | struct btrfs_root *reloc_root) | |
2261 | { | |
2262 | struct btrfs_root *root; | |
2263 | ||
2264 | if (reloc_root->last_trans == trans->transid) | |
2265 | return 0; | |
2266 | ||
2267 | root = read_fs_root(reloc_root->fs_info, reloc_root->root_key.offset); | |
2268 | BUG_ON(IS_ERR(root)); | |
2269 | BUG_ON(root->reloc_root != reloc_root); | |
2270 | ||
2271 | return btrfs_record_root_in_trans(trans, root); | |
2272 | } | |
2273 | ||
3fd0a558 YZ |
2274 | static noinline_for_stack |
2275 | struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans, | |
2276 | struct reloc_control *rc, | |
2277 | struct backref_node *node, | |
2278 | struct backref_edge *edges[], int *nr) | |
5d4f98a2 YZ |
2279 | { |
2280 | struct backref_node *next; | |
2281 | struct btrfs_root *root; | |
3fd0a558 YZ |
2282 | int index = 0; |
2283 | ||
5d4f98a2 YZ |
2284 | next = node; |
2285 | while (1) { | |
2286 | cond_resched(); | |
2287 | next = walk_up_backref(next, edges, &index); | |
2288 | root = next->root; | |
3fd0a558 YZ |
2289 | BUG_ON(!root); |
2290 | BUG_ON(!root->ref_cows); | |
5d4f98a2 YZ |
2291 | |
2292 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { | |
2293 | record_reloc_root_in_trans(trans, root); | |
2294 | break; | |
2295 | } | |
2296 | ||
3fd0a558 YZ |
2297 | btrfs_record_root_in_trans(trans, root); |
2298 | root = root->reloc_root; | |
2299 | ||
2300 | if (next->new_bytenr != root->node->start) { | |
2301 | BUG_ON(next->new_bytenr); | |
2302 | BUG_ON(!list_empty(&next->list)); | |
2303 | next->new_bytenr = root->node->start; | |
2304 | next->root = root; | |
2305 | list_add_tail(&next->list, | |
2306 | &rc->backref_cache.changed); | |
2307 | __mark_block_processed(rc, next); | |
5d4f98a2 YZ |
2308 | break; |
2309 | } | |
2310 | ||
3fd0a558 | 2311 | WARN_ON(1); |
5d4f98a2 YZ |
2312 | root = NULL; |
2313 | next = walk_down_backref(edges, &index); | |
2314 | if (!next || next->level <= node->level) | |
2315 | break; | |
2316 | } | |
3fd0a558 YZ |
2317 | if (!root) |
2318 | return NULL; | |
5d4f98a2 | 2319 | |
3fd0a558 YZ |
2320 | *nr = index; |
2321 | next = node; | |
2322 | /* setup backref node path for btrfs_reloc_cow_block */ | |
2323 | while (1) { | |
2324 | rc->backref_cache.path[next->level] = next; | |
2325 | if (--index < 0) | |
2326 | break; | |
2327 | next = edges[index]->node[UPPER]; | |
5d4f98a2 | 2328 | } |
5d4f98a2 YZ |
2329 | return root; |
2330 | } | |
2331 | ||
3fd0a558 YZ |
2332 | /* |
2333 | * select a tree root for relocation. return NULL if the block | |
2334 | * is reference counted. we should use do_relocation() in this | |
2335 | * case. return a tree root pointer if the block isn't reference | |
2336 | * counted. return -ENOENT if the block is root of reloc tree. | |
2337 | */ | |
5d4f98a2 YZ |
2338 | static noinline_for_stack |
2339 | struct btrfs_root *select_one_root(struct btrfs_trans_handle *trans, | |
2340 | struct backref_node *node) | |
2341 | { | |
3fd0a558 YZ |
2342 | struct backref_node *next; |
2343 | struct btrfs_root *root; | |
2344 | struct btrfs_root *fs_root = NULL; | |
5d4f98a2 | 2345 | struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; |
3fd0a558 YZ |
2346 | int index = 0; |
2347 | ||
2348 | next = node; | |
2349 | while (1) { | |
2350 | cond_resched(); | |
2351 | next = walk_up_backref(next, edges, &index); | |
2352 | root = next->root; | |
2353 | BUG_ON(!root); | |
2354 | ||
25985edc | 2355 | /* no other choice for non-references counted tree */ |
3fd0a558 YZ |
2356 | if (!root->ref_cows) |
2357 | return root; | |
2358 | ||
2359 | if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) | |
2360 | fs_root = root; | |
2361 | ||
2362 | if (next != node) | |
2363 | return NULL; | |
2364 | ||
2365 | next = walk_down_backref(edges, &index); | |
2366 | if (!next || next->level <= node->level) | |
2367 | break; | |
2368 | } | |
2369 | ||
2370 | if (!fs_root) | |
2371 | return ERR_PTR(-ENOENT); | |
2372 | return fs_root; | |
5d4f98a2 YZ |
2373 | } |
2374 | ||
2375 | static noinline_for_stack | |
3fd0a558 YZ |
2376 | u64 calcu_metadata_size(struct reloc_control *rc, |
2377 | struct backref_node *node, int reserve) | |
5d4f98a2 | 2378 | { |
3fd0a558 YZ |
2379 | struct backref_node *next = node; |
2380 | struct backref_edge *edge; | |
2381 | struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; | |
2382 | u64 num_bytes = 0; | |
2383 | int index = 0; | |
2384 | ||
2385 | BUG_ON(reserve && node->processed); | |
2386 | ||
2387 | while (next) { | |
2388 | cond_resched(); | |
2389 | while (1) { | |
2390 | if (next->processed && (reserve || next != node)) | |
2391 | break; | |
2392 | ||
2393 | num_bytes += btrfs_level_size(rc->extent_root, | |
2394 | next->level); | |
2395 | ||
2396 | if (list_empty(&next->upper)) | |
2397 | break; | |
2398 | ||
2399 | edge = list_entry(next->upper.next, | |
2400 | struct backref_edge, list[LOWER]); | |
2401 | edges[index++] = edge; | |
2402 | next = edge->node[UPPER]; | |
2403 | } | |
2404 | next = walk_down_backref(edges, &index); | |
2405 | } | |
2406 | return num_bytes; | |
5d4f98a2 YZ |
2407 | } |
2408 | ||
3fd0a558 YZ |
2409 | static int reserve_metadata_space(struct btrfs_trans_handle *trans, |
2410 | struct reloc_control *rc, | |
2411 | struct backref_node *node) | |
5d4f98a2 | 2412 | { |
3fd0a558 YZ |
2413 | struct btrfs_root *root = rc->extent_root; |
2414 | u64 num_bytes; | |
2415 | int ret; | |
2416 | ||
2417 | num_bytes = calcu_metadata_size(rc, node, 1) * 2; | |
5d4f98a2 | 2418 | |
3fd0a558 | 2419 | trans->block_rsv = rc->block_rsv; |
8bb8ab2e | 2420 | ret = btrfs_block_rsv_add(trans, root, rc->block_rsv, num_bytes); |
3fd0a558 YZ |
2421 | if (ret) { |
2422 | if (ret == -EAGAIN) | |
2423 | rc->commit_transaction = 1; | |
2424 | return ret; | |
5d4f98a2 | 2425 | } |
3fd0a558 | 2426 | |
3fd0a558 YZ |
2427 | return 0; |
2428 | } | |
2429 | ||
2430 | static void release_metadata_space(struct reloc_control *rc, | |
2431 | struct backref_node *node) | |
2432 | { | |
2433 | u64 num_bytes = calcu_metadata_size(rc, node, 0) * 2; | |
2434 | btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, num_bytes); | |
5d4f98a2 YZ |
2435 | } |
2436 | ||
2437 | /* | |
2438 | * relocate a block tree, and then update pointers in upper level | |
2439 | * blocks that reference the block to point to the new location. | |
2440 | * | |
2441 | * if called by link_to_upper, the block has already been relocated. | |
2442 | * in that case this function just updates pointers. | |
2443 | */ | |
2444 | static int do_relocation(struct btrfs_trans_handle *trans, | |
3fd0a558 | 2445 | struct reloc_control *rc, |
5d4f98a2 YZ |
2446 | struct backref_node *node, |
2447 | struct btrfs_key *key, | |
2448 | struct btrfs_path *path, int lowest) | |
2449 | { | |
2450 | struct backref_node *upper; | |
2451 | struct backref_edge *edge; | |
2452 | struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; | |
2453 | struct btrfs_root *root; | |
2454 | struct extent_buffer *eb; | |
2455 | u32 blocksize; | |
2456 | u64 bytenr; | |
2457 | u64 generation; | |
2458 | int nr; | |
2459 | int slot; | |
2460 | int ret; | |
2461 | int err = 0; | |
2462 | ||
2463 | BUG_ON(lowest && node->eb); | |
2464 | ||
2465 | path->lowest_level = node->level + 1; | |
3fd0a558 | 2466 | rc->backref_cache.path[node->level] = node; |
5d4f98a2 YZ |
2467 | list_for_each_entry(edge, &node->upper, list[LOWER]) { |
2468 | cond_resched(); | |
5d4f98a2 YZ |
2469 | |
2470 | upper = edge->node[UPPER]; | |
3fd0a558 YZ |
2471 | root = select_reloc_root(trans, rc, upper, edges, &nr); |
2472 | BUG_ON(!root); | |
2473 | ||
2474 | if (upper->eb && !upper->locked) { | |
2475 | if (!lowest) { | |
2476 | ret = btrfs_bin_search(upper->eb, key, | |
2477 | upper->level, &slot); | |
2478 | BUG_ON(ret); | |
2479 | bytenr = btrfs_node_blockptr(upper->eb, slot); | |
2480 | if (node->eb->start == bytenr) | |
2481 | goto next; | |
2482 | } | |
5d4f98a2 | 2483 | drop_node_buffer(upper); |
3fd0a558 | 2484 | } |
5d4f98a2 YZ |
2485 | |
2486 | if (!upper->eb) { | |
2487 | ret = btrfs_search_slot(trans, root, key, path, 0, 1); | |
2488 | if (ret < 0) { | |
2489 | err = ret; | |
2490 | break; | |
2491 | } | |
2492 | BUG_ON(ret > 0); | |
2493 | ||
3fd0a558 YZ |
2494 | if (!upper->eb) { |
2495 | upper->eb = path->nodes[upper->level]; | |
2496 | path->nodes[upper->level] = NULL; | |
2497 | } else { | |
2498 | BUG_ON(upper->eb != path->nodes[upper->level]); | |
2499 | } | |
5d4f98a2 | 2500 | |
3fd0a558 YZ |
2501 | upper->locked = 1; |
2502 | path->locks[upper->level] = 0; | |
5d4f98a2 | 2503 | |
3fd0a558 | 2504 | slot = path->slots[upper->level]; |
b3b4aa74 | 2505 | btrfs_release_path(path); |
5d4f98a2 YZ |
2506 | } else { |
2507 | ret = btrfs_bin_search(upper->eb, key, upper->level, | |
2508 | &slot); | |
2509 | BUG_ON(ret); | |
2510 | } | |
2511 | ||
2512 | bytenr = btrfs_node_blockptr(upper->eb, slot); | |
3fd0a558 YZ |
2513 | if (lowest) { |
2514 | BUG_ON(bytenr != node->bytenr); | |
5d4f98a2 | 2515 | } else { |
3fd0a558 YZ |
2516 | if (node->eb->start == bytenr) |
2517 | goto next; | |
5d4f98a2 YZ |
2518 | } |
2519 | ||
2520 | blocksize = btrfs_level_size(root, node->level); | |
2521 | generation = btrfs_node_ptr_generation(upper->eb, slot); | |
2522 | eb = read_tree_block(root, bytenr, blocksize, generation); | |
97d9a8a4 TI |
2523 | if (!eb) { |
2524 | err = -EIO; | |
2525 | goto next; | |
2526 | } | |
5d4f98a2 YZ |
2527 | btrfs_tree_lock(eb); |
2528 | btrfs_set_lock_blocking(eb); | |
2529 | ||
2530 | if (!node->eb) { | |
2531 | ret = btrfs_cow_block(trans, root, eb, upper->eb, | |
2532 | slot, &eb); | |
3fd0a558 YZ |
2533 | btrfs_tree_unlock(eb); |
2534 | free_extent_buffer(eb); | |
5d4f98a2 YZ |
2535 | if (ret < 0) { |
2536 | err = ret; | |
3fd0a558 | 2537 | goto next; |
5d4f98a2 | 2538 | } |
3fd0a558 | 2539 | BUG_ON(node->eb != eb); |
5d4f98a2 YZ |
2540 | } else { |
2541 | btrfs_set_node_blockptr(upper->eb, slot, | |
2542 | node->eb->start); | |
2543 | btrfs_set_node_ptr_generation(upper->eb, slot, | |
2544 | trans->transid); | |
2545 | btrfs_mark_buffer_dirty(upper->eb); | |
2546 | ||
2547 | ret = btrfs_inc_extent_ref(trans, root, | |
2548 | node->eb->start, blocksize, | |
2549 | upper->eb->start, | |
2550 | btrfs_header_owner(upper->eb), | |
2551 | node->level, 0); | |
2552 | BUG_ON(ret); | |
2553 | ||
2554 | ret = btrfs_drop_subtree(trans, root, eb, upper->eb); | |
2555 | BUG_ON(ret); | |
5d4f98a2 | 2556 | } |
3fd0a558 YZ |
2557 | next: |
2558 | if (!upper->pending) | |
2559 | drop_node_buffer(upper); | |
2560 | else | |
2561 | unlock_node_buffer(upper); | |
2562 | if (err) | |
2563 | break; | |
5d4f98a2 | 2564 | } |
3fd0a558 YZ |
2565 | |
2566 | if (!err && node->pending) { | |
2567 | drop_node_buffer(node); | |
2568 | list_move_tail(&node->list, &rc->backref_cache.changed); | |
2569 | node->pending = 0; | |
2570 | } | |
2571 | ||
5d4f98a2 | 2572 | path->lowest_level = 0; |
3fd0a558 | 2573 | BUG_ON(err == -ENOSPC); |
5d4f98a2 YZ |
2574 | return err; |
2575 | } | |
2576 | ||
2577 | static int link_to_upper(struct btrfs_trans_handle *trans, | |
3fd0a558 | 2578 | struct reloc_control *rc, |
5d4f98a2 YZ |
2579 | struct backref_node *node, |
2580 | struct btrfs_path *path) | |
2581 | { | |
2582 | struct btrfs_key key; | |
5d4f98a2 YZ |
2583 | |
2584 | btrfs_node_key_to_cpu(node->eb, &key, 0); | |
3fd0a558 | 2585 | return do_relocation(trans, rc, node, &key, path, 0); |
5d4f98a2 YZ |
2586 | } |
2587 | ||
2588 | static int finish_pending_nodes(struct btrfs_trans_handle *trans, | |
3fd0a558 YZ |
2589 | struct reloc_control *rc, |
2590 | struct btrfs_path *path, int err) | |
5d4f98a2 | 2591 | { |
3fd0a558 YZ |
2592 | LIST_HEAD(list); |
2593 | struct backref_cache *cache = &rc->backref_cache; | |
5d4f98a2 YZ |
2594 | struct backref_node *node; |
2595 | int level; | |
2596 | int ret; | |
5d4f98a2 YZ |
2597 | |
2598 | for (level = 0; level < BTRFS_MAX_LEVEL; level++) { | |
2599 | while (!list_empty(&cache->pending[level])) { | |
2600 | node = list_entry(cache->pending[level].next, | |
3fd0a558 YZ |
2601 | struct backref_node, list); |
2602 | list_move_tail(&node->list, &list); | |
2603 | BUG_ON(!node->pending); | |
5d4f98a2 | 2604 | |
3fd0a558 YZ |
2605 | if (!err) { |
2606 | ret = link_to_upper(trans, rc, node, path); | |
2607 | if (ret < 0) | |
2608 | err = ret; | |
2609 | } | |
5d4f98a2 | 2610 | } |
3fd0a558 | 2611 | list_splice_init(&list, &cache->pending[level]); |
5d4f98a2 | 2612 | } |
5d4f98a2 YZ |
2613 | return err; |
2614 | } | |
2615 | ||
2616 | static void mark_block_processed(struct reloc_control *rc, | |
3fd0a558 YZ |
2617 | u64 bytenr, u32 blocksize) |
2618 | { | |
2619 | set_extent_bits(&rc->processed_blocks, bytenr, bytenr + blocksize - 1, | |
2620 | EXTENT_DIRTY, GFP_NOFS); | |
2621 | } | |
2622 | ||
2623 | static void __mark_block_processed(struct reloc_control *rc, | |
2624 | struct backref_node *node) | |
5d4f98a2 YZ |
2625 | { |
2626 | u32 blocksize; | |
2627 | if (node->level == 0 || | |
2628 | in_block_group(node->bytenr, rc->block_group)) { | |
2629 | blocksize = btrfs_level_size(rc->extent_root, node->level); | |
3fd0a558 | 2630 | mark_block_processed(rc, node->bytenr, blocksize); |
5d4f98a2 YZ |
2631 | } |
2632 | node->processed = 1; | |
2633 | } | |
2634 | ||
2635 | /* | |
2636 | * mark a block and all blocks directly/indirectly reference the block | |
2637 | * as processed. | |
2638 | */ | |
2639 | static void update_processed_blocks(struct reloc_control *rc, | |
2640 | struct backref_node *node) | |
2641 | { | |
2642 | struct backref_node *next = node; | |
2643 | struct backref_edge *edge; | |
2644 | struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; | |
2645 | int index = 0; | |
2646 | ||
2647 | while (next) { | |
2648 | cond_resched(); | |
2649 | while (1) { | |
2650 | if (next->processed) | |
2651 | break; | |
2652 | ||
3fd0a558 | 2653 | __mark_block_processed(rc, next); |
5d4f98a2 YZ |
2654 | |
2655 | if (list_empty(&next->upper)) | |
2656 | break; | |
2657 | ||
2658 | edge = list_entry(next->upper.next, | |
2659 | struct backref_edge, list[LOWER]); | |
2660 | edges[index++] = edge; | |
2661 | next = edge->node[UPPER]; | |
2662 | } | |
2663 | next = walk_down_backref(edges, &index); | |
2664 | } | |
2665 | } | |
2666 | ||
3fd0a558 YZ |
2667 | static int tree_block_processed(u64 bytenr, u32 blocksize, |
2668 | struct reloc_control *rc) | |
2669 | { | |
2670 | if (test_range_bit(&rc->processed_blocks, bytenr, | |
2671 | bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL)) | |
2672 | return 1; | |
2673 | return 0; | |
5d4f98a2 YZ |
2674 | } |
2675 | ||
2676 | static int get_tree_block_key(struct reloc_control *rc, | |
2677 | struct tree_block *block) | |
2678 | { | |
2679 | struct extent_buffer *eb; | |
2680 | ||
2681 | BUG_ON(block->key_ready); | |
2682 | eb = read_tree_block(rc->extent_root, block->bytenr, | |
2683 | block->key.objectid, block->key.offset); | |
97d9a8a4 | 2684 | BUG_ON(!eb); |
5d4f98a2 YZ |
2685 | WARN_ON(btrfs_header_level(eb) != block->level); |
2686 | if (block->level == 0) | |
2687 | btrfs_item_key_to_cpu(eb, &block->key, 0); | |
2688 | else | |
2689 | btrfs_node_key_to_cpu(eb, &block->key, 0); | |
2690 | free_extent_buffer(eb); | |
2691 | block->key_ready = 1; | |
2692 | return 0; | |
2693 | } | |
2694 | ||
2695 | static int reada_tree_block(struct reloc_control *rc, | |
2696 | struct tree_block *block) | |
2697 | { | |
2698 | BUG_ON(block->key_ready); | |
2699 | readahead_tree_block(rc->extent_root, block->bytenr, | |
2700 | block->key.objectid, block->key.offset); | |
2701 | return 0; | |
2702 | } | |
2703 | ||
2704 | /* | |
2705 | * helper function to relocate a tree block | |
2706 | */ | |
2707 | static int relocate_tree_block(struct btrfs_trans_handle *trans, | |
2708 | struct reloc_control *rc, | |
2709 | struct backref_node *node, | |
2710 | struct btrfs_key *key, | |
2711 | struct btrfs_path *path) | |
2712 | { | |
2713 | struct btrfs_root *root; | |
3fd0a558 YZ |
2714 | int release = 0; |
2715 | int ret = 0; | |
2716 | ||
2717 | if (!node) | |
2718 | return 0; | |
5d4f98a2 | 2719 | |
3fd0a558 | 2720 | BUG_ON(node->processed); |
5d4f98a2 | 2721 | root = select_one_root(trans, node); |
3fd0a558 | 2722 | if (root == ERR_PTR(-ENOENT)) { |
5d4f98a2 | 2723 | update_processed_blocks(rc, node); |
3fd0a558 | 2724 | goto out; |
5d4f98a2 YZ |
2725 | } |
2726 | ||
3fd0a558 YZ |
2727 | if (!root || root->ref_cows) { |
2728 | ret = reserve_metadata_space(trans, rc, node); | |
2729 | if (ret) | |
5d4f98a2 | 2730 | goto out; |
3fd0a558 | 2731 | release = 1; |
5d4f98a2 YZ |
2732 | } |
2733 | ||
3fd0a558 YZ |
2734 | if (root) { |
2735 | if (root->ref_cows) { | |
2736 | BUG_ON(node->new_bytenr); | |
2737 | BUG_ON(!list_empty(&node->list)); | |
2738 | btrfs_record_root_in_trans(trans, root); | |
2739 | root = root->reloc_root; | |
2740 | node->new_bytenr = root->node->start; | |
2741 | node->root = root; | |
2742 | list_add_tail(&node->list, &rc->backref_cache.changed); | |
2743 | } else { | |
2744 | path->lowest_level = node->level; | |
2745 | ret = btrfs_search_slot(trans, root, key, path, 0, 1); | |
b3b4aa74 | 2746 | btrfs_release_path(path); |
3fd0a558 YZ |
2747 | if (ret > 0) |
2748 | ret = 0; | |
2749 | } | |
2750 | if (!ret) | |
2751 | update_processed_blocks(rc, node); | |
2752 | } else { | |
2753 | ret = do_relocation(trans, rc, node, key, path, 1); | |
2754 | } | |
5d4f98a2 | 2755 | out: |
3fd0a558 YZ |
2756 | if (ret || node->level == 0 || node->cowonly) { |
2757 | if (release) | |
2758 | release_metadata_space(rc, node); | |
2759 | remove_backref_node(&rc->backref_cache, node); | |
2760 | } | |
5d4f98a2 YZ |
2761 | return ret; |
2762 | } | |
2763 | ||
2764 | /* | |
2765 | * relocate a list of blocks | |
2766 | */ | |
2767 | static noinline_for_stack | |
2768 | int relocate_tree_blocks(struct btrfs_trans_handle *trans, | |
2769 | struct reloc_control *rc, struct rb_root *blocks) | |
2770 | { | |
5d4f98a2 YZ |
2771 | struct backref_node *node; |
2772 | struct btrfs_path *path; | |
2773 | struct tree_block *block; | |
2774 | struct rb_node *rb_node; | |
5d4f98a2 YZ |
2775 | int ret; |
2776 | int err = 0; | |
2777 | ||
2778 | path = btrfs_alloc_path(); | |
2779 | if (!path) | |
2780 | return -ENOMEM; | |
2781 | ||
5d4f98a2 YZ |
2782 | rb_node = rb_first(blocks); |
2783 | while (rb_node) { | |
2784 | block = rb_entry(rb_node, struct tree_block, rb_node); | |
5d4f98a2 YZ |
2785 | if (!block->key_ready) |
2786 | reada_tree_block(rc, block); | |
2787 | rb_node = rb_next(rb_node); | |
2788 | } | |
2789 | ||
2790 | rb_node = rb_first(blocks); | |
2791 | while (rb_node) { | |
2792 | block = rb_entry(rb_node, struct tree_block, rb_node); | |
2793 | if (!block->key_ready) | |
2794 | get_tree_block_key(rc, block); | |
2795 | rb_node = rb_next(rb_node); | |
2796 | } | |
2797 | ||
2798 | rb_node = rb_first(blocks); | |
2799 | while (rb_node) { | |
2800 | block = rb_entry(rb_node, struct tree_block, rb_node); | |
2801 | ||
3fd0a558 | 2802 | node = build_backref_tree(rc, &block->key, |
5d4f98a2 YZ |
2803 | block->level, block->bytenr); |
2804 | if (IS_ERR(node)) { | |
2805 | err = PTR_ERR(node); | |
2806 | goto out; | |
2807 | } | |
2808 | ||
2809 | ret = relocate_tree_block(trans, rc, node, &block->key, | |
2810 | path); | |
2811 | if (ret < 0) { | |
3fd0a558 YZ |
2812 | if (ret != -EAGAIN || rb_node == rb_first(blocks)) |
2813 | err = ret; | |
5d4f98a2 YZ |
2814 | goto out; |
2815 | } | |
5d4f98a2 YZ |
2816 | rb_node = rb_next(rb_node); |
2817 | } | |
5d4f98a2 YZ |
2818 | out: |
2819 | free_block_list(blocks); | |
3fd0a558 | 2820 | err = finish_pending_nodes(trans, rc, path, err); |
5d4f98a2 | 2821 | |
5d4f98a2 YZ |
2822 | btrfs_free_path(path); |
2823 | return err; | |
2824 | } | |
2825 | ||
efa56464 YZ |
2826 | static noinline_for_stack |
2827 | int prealloc_file_extent_cluster(struct inode *inode, | |
2828 | struct file_extent_cluster *cluster) | |
2829 | { | |
2830 | u64 alloc_hint = 0; | |
2831 | u64 start; | |
2832 | u64 end; | |
2833 | u64 offset = BTRFS_I(inode)->index_cnt; | |
2834 | u64 num_bytes; | |
2835 | int nr = 0; | |
2836 | int ret = 0; | |
2837 | ||
2838 | BUG_ON(cluster->start != cluster->boundary[0]); | |
2839 | mutex_lock(&inode->i_mutex); | |
2840 | ||
2841 | ret = btrfs_check_data_free_space(inode, cluster->end + | |
2842 | 1 - cluster->start); | |
2843 | if (ret) | |
2844 | goto out; | |
2845 | ||
2846 | while (nr < cluster->nr) { | |
2847 | start = cluster->boundary[nr] - offset; | |
2848 | if (nr + 1 < cluster->nr) | |
2849 | end = cluster->boundary[nr + 1] - 1 - offset; | |
2850 | else | |
2851 | end = cluster->end - offset; | |
2852 | ||
2853 | lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
2854 | num_bytes = end + 1 - start; | |
2855 | ret = btrfs_prealloc_file_range(inode, 0, start, | |
2856 | num_bytes, num_bytes, | |
2857 | end + 1, &alloc_hint); | |
2858 | unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
2859 | if (ret) | |
2860 | break; | |
2861 | nr++; | |
2862 | } | |
2863 | btrfs_free_reserved_data_space(inode, cluster->end + | |
2864 | 1 - cluster->start); | |
2865 | out: | |
2866 | mutex_unlock(&inode->i_mutex); | |
2867 | return ret; | |
2868 | } | |
2869 | ||
5d4f98a2 | 2870 | static noinline_for_stack |
0257bb82 YZ |
2871 | int setup_extent_mapping(struct inode *inode, u64 start, u64 end, |
2872 | u64 block_start) | |
2873 | { | |
2874 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
2875 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; | |
2876 | struct extent_map *em; | |
2877 | int ret = 0; | |
2878 | ||
172ddd60 | 2879 | em = alloc_extent_map(); |
0257bb82 YZ |
2880 | if (!em) |
2881 | return -ENOMEM; | |
2882 | ||
2883 | em->start = start; | |
2884 | em->len = end + 1 - start; | |
2885 | em->block_len = em->len; | |
2886 | em->block_start = block_start; | |
2887 | em->bdev = root->fs_info->fs_devices->latest_bdev; | |
2888 | set_bit(EXTENT_FLAG_PINNED, &em->flags); | |
2889 | ||
2890 | lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
2891 | while (1) { | |
2892 | write_lock(&em_tree->lock); | |
2893 | ret = add_extent_mapping(em_tree, em); | |
2894 | write_unlock(&em_tree->lock); | |
2895 | if (ret != -EEXIST) { | |
2896 | free_extent_map(em); | |
2897 | break; | |
2898 | } | |
2899 | btrfs_drop_extent_cache(inode, start, end, 0); | |
2900 | } | |
2901 | unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
2902 | return ret; | |
2903 | } | |
2904 | ||
2905 | static int relocate_file_extent_cluster(struct inode *inode, | |
2906 | struct file_extent_cluster *cluster) | |
5d4f98a2 YZ |
2907 | { |
2908 | u64 page_start; | |
2909 | u64 page_end; | |
0257bb82 YZ |
2910 | u64 offset = BTRFS_I(inode)->index_cnt; |
2911 | unsigned long index; | |
5d4f98a2 | 2912 | unsigned long last_index; |
5d4f98a2 YZ |
2913 | struct page *page; |
2914 | struct file_ra_state *ra; | |
0257bb82 | 2915 | int nr = 0; |
5d4f98a2 YZ |
2916 | int ret = 0; |
2917 | ||
0257bb82 YZ |
2918 | if (!cluster->nr) |
2919 | return 0; | |
2920 | ||
5d4f98a2 YZ |
2921 | ra = kzalloc(sizeof(*ra), GFP_NOFS); |
2922 | if (!ra) | |
2923 | return -ENOMEM; | |
2924 | ||
efa56464 YZ |
2925 | ret = prealloc_file_extent_cluster(inode, cluster); |
2926 | if (ret) | |
2927 | goto out; | |
0257bb82 | 2928 | |
efa56464 | 2929 | file_ra_state_init(ra, inode->i_mapping); |
5d4f98a2 | 2930 | |
0257bb82 YZ |
2931 | ret = setup_extent_mapping(inode, cluster->start - offset, |
2932 | cluster->end - offset, cluster->start); | |
5d4f98a2 | 2933 | if (ret) |
efa56464 | 2934 | goto out; |
5d4f98a2 | 2935 | |
efa56464 YZ |
2936 | index = (cluster->start - offset) >> PAGE_CACHE_SHIFT; |
2937 | last_index = (cluster->end - offset) >> PAGE_CACHE_SHIFT; | |
0257bb82 | 2938 | while (index <= last_index) { |
efa56464 YZ |
2939 | ret = btrfs_delalloc_reserve_metadata(inode, PAGE_CACHE_SIZE); |
2940 | if (ret) | |
2941 | goto out; | |
2942 | ||
0257bb82 | 2943 | page = find_lock_page(inode->i_mapping, index); |
5d4f98a2 | 2944 | if (!page) { |
0257bb82 YZ |
2945 | page_cache_sync_readahead(inode->i_mapping, |
2946 | ra, NULL, index, | |
2947 | last_index + 1 - index); | |
2948 | page = grab_cache_page(inode->i_mapping, index); | |
2949 | if (!page) { | |
efa56464 YZ |
2950 | btrfs_delalloc_release_metadata(inode, |
2951 | PAGE_CACHE_SIZE); | |
0257bb82 | 2952 | ret = -ENOMEM; |
efa56464 | 2953 | goto out; |
0257bb82 | 2954 | } |
5d4f98a2 | 2955 | } |
0257bb82 YZ |
2956 | |
2957 | if (PageReadahead(page)) { | |
2958 | page_cache_async_readahead(inode->i_mapping, | |
2959 | ra, NULL, page, index, | |
2960 | last_index + 1 - index); | |
2961 | } | |
2962 | ||
5d4f98a2 YZ |
2963 | if (!PageUptodate(page)) { |
2964 | btrfs_readpage(NULL, page); | |
2965 | lock_page(page); | |
2966 | if (!PageUptodate(page)) { | |
2967 | unlock_page(page); | |
2968 | page_cache_release(page); | |
efa56464 YZ |
2969 | btrfs_delalloc_release_metadata(inode, |
2970 | PAGE_CACHE_SIZE); | |
5d4f98a2 | 2971 | ret = -EIO; |
efa56464 | 2972 | goto out; |
5d4f98a2 YZ |
2973 | } |
2974 | } | |
5d4f98a2 YZ |
2975 | |
2976 | page_start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2977 | page_end = page_start + PAGE_CACHE_SIZE - 1; | |
0257bb82 YZ |
2978 | |
2979 | lock_extent(&BTRFS_I(inode)->io_tree, | |
2980 | page_start, page_end, GFP_NOFS); | |
2981 | ||
5d4f98a2 YZ |
2982 | set_page_extent_mapped(page); |
2983 | ||
0257bb82 YZ |
2984 | if (nr < cluster->nr && |
2985 | page_start + offset == cluster->boundary[nr]) { | |
2986 | set_extent_bits(&BTRFS_I(inode)->io_tree, | |
2987 | page_start, page_end, | |
5d4f98a2 | 2988 | EXTENT_BOUNDARY, GFP_NOFS); |
0257bb82 YZ |
2989 | nr++; |
2990 | } | |
5d4f98a2 | 2991 | |
efa56464 | 2992 | btrfs_set_extent_delalloc(inode, page_start, page_end, NULL); |
5d4f98a2 | 2993 | set_page_dirty(page); |
5d4f98a2 | 2994 | |
0257bb82 YZ |
2995 | unlock_extent(&BTRFS_I(inode)->io_tree, |
2996 | page_start, page_end, GFP_NOFS); | |
5d4f98a2 YZ |
2997 | unlock_page(page); |
2998 | page_cache_release(page); | |
0257bb82 YZ |
2999 | |
3000 | index++; | |
efa56464 YZ |
3001 | balance_dirty_pages_ratelimited(inode->i_mapping); |
3002 | btrfs_throttle(BTRFS_I(inode)->root); | |
5d4f98a2 | 3003 | } |
0257bb82 | 3004 | WARN_ON(nr != cluster->nr); |
efa56464 | 3005 | out: |
5d4f98a2 | 3006 | kfree(ra); |
5d4f98a2 YZ |
3007 | return ret; |
3008 | } | |
3009 | ||
3010 | static noinline_for_stack | |
0257bb82 YZ |
3011 | int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key, |
3012 | struct file_extent_cluster *cluster) | |
5d4f98a2 | 3013 | { |
0257bb82 | 3014 | int ret; |
5d4f98a2 | 3015 | |
0257bb82 YZ |
3016 | if (cluster->nr > 0 && extent_key->objectid != cluster->end + 1) { |
3017 | ret = relocate_file_extent_cluster(inode, cluster); | |
3018 | if (ret) | |
3019 | return ret; | |
3020 | cluster->nr = 0; | |
5d4f98a2 | 3021 | } |
5d4f98a2 | 3022 | |
0257bb82 YZ |
3023 | if (!cluster->nr) |
3024 | cluster->start = extent_key->objectid; | |
3025 | else | |
3026 | BUG_ON(cluster->nr >= MAX_EXTENTS); | |
3027 | cluster->end = extent_key->objectid + extent_key->offset - 1; | |
3028 | cluster->boundary[cluster->nr] = extent_key->objectid; | |
3029 | cluster->nr++; | |
3030 | ||
3031 | if (cluster->nr >= MAX_EXTENTS) { | |
3032 | ret = relocate_file_extent_cluster(inode, cluster); | |
3033 | if (ret) | |
3034 | return ret; | |
3035 | cluster->nr = 0; | |
3036 | } | |
3037 | return 0; | |
5d4f98a2 YZ |
3038 | } |
3039 | ||
3040 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
3041 | static int get_ref_objectid_v0(struct reloc_control *rc, | |
3042 | struct btrfs_path *path, | |
3043 | struct btrfs_key *extent_key, | |
3044 | u64 *ref_objectid, int *path_change) | |
3045 | { | |
3046 | struct btrfs_key key; | |
3047 | struct extent_buffer *leaf; | |
3048 | struct btrfs_extent_ref_v0 *ref0; | |
3049 | int ret; | |
3050 | int slot; | |
3051 | ||
3052 | leaf = path->nodes[0]; | |
3053 | slot = path->slots[0]; | |
3054 | while (1) { | |
3055 | if (slot >= btrfs_header_nritems(leaf)) { | |
3056 | ret = btrfs_next_leaf(rc->extent_root, path); | |
3057 | if (ret < 0) | |
3058 | return ret; | |
3059 | BUG_ON(ret > 0); | |
3060 | leaf = path->nodes[0]; | |
3061 | slot = path->slots[0]; | |
3062 | if (path_change) | |
3063 | *path_change = 1; | |
3064 | } | |
3065 | btrfs_item_key_to_cpu(leaf, &key, slot); | |
3066 | if (key.objectid != extent_key->objectid) | |
3067 | return -ENOENT; | |
3068 | ||
3069 | if (key.type != BTRFS_EXTENT_REF_V0_KEY) { | |
3070 | slot++; | |
3071 | continue; | |
3072 | } | |
3073 | ref0 = btrfs_item_ptr(leaf, slot, | |
3074 | struct btrfs_extent_ref_v0); | |
3075 | *ref_objectid = btrfs_ref_objectid_v0(leaf, ref0); | |
3076 | break; | |
3077 | } | |
3078 | return 0; | |
3079 | } | |
3080 | #endif | |
3081 | ||
3082 | /* | |
3083 | * helper to add a tree block to the list. | |
3084 | * the major work is getting the generation and level of the block | |
3085 | */ | |
3086 | static int add_tree_block(struct reloc_control *rc, | |
3087 | struct btrfs_key *extent_key, | |
3088 | struct btrfs_path *path, | |
3089 | struct rb_root *blocks) | |
3090 | { | |
3091 | struct extent_buffer *eb; | |
3092 | struct btrfs_extent_item *ei; | |
3093 | struct btrfs_tree_block_info *bi; | |
3094 | struct tree_block *block; | |
3095 | struct rb_node *rb_node; | |
3096 | u32 item_size; | |
3097 | int level = -1; | |
3098 | int generation; | |
3099 | ||
3100 | eb = path->nodes[0]; | |
3101 | item_size = btrfs_item_size_nr(eb, path->slots[0]); | |
3102 | ||
3103 | if (item_size >= sizeof(*ei) + sizeof(*bi)) { | |
3104 | ei = btrfs_item_ptr(eb, path->slots[0], | |
3105 | struct btrfs_extent_item); | |
3106 | bi = (struct btrfs_tree_block_info *)(ei + 1); | |
3107 | generation = btrfs_extent_generation(eb, ei); | |
3108 | level = btrfs_tree_block_level(eb, bi); | |
3109 | } else { | |
3110 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
3111 | u64 ref_owner; | |
3112 | int ret; | |
3113 | ||
3114 | BUG_ON(item_size != sizeof(struct btrfs_extent_item_v0)); | |
3115 | ret = get_ref_objectid_v0(rc, path, extent_key, | |
3116 | &ref_owner, NULL); | |
411fc6bc AK |
3117 | if (ret < 0) |
3118 | return ret; | |
5d4f98a2 YZ |
3119 | BUG_ON(ref_owner >= BTRFS_MAX_LEVEL); |
3120 | level = (int)ref_owner; | |
3121 | /* FIXME: get real generation */ | |
3122 | generation = 0; | |
3123 | #else | |
3124 | BUG(); | |
3125 | #endif | |
3126 | } | |
3127 | ||
b3b4aa74 | 3128 | btrfs_release_path(path); |
5d4f98a2 YZ |
3129 | |
3130 | BUG_ON(level == -1); | |
3131 | ||
3132 | block = kmalloc(sizeof(*block), GFP_NOFS); | |
3133 | if (!block) | |
3134 | return -ENOMEM; | |
3135 | ||
3136 | block->bytenr = extent_key->objectid; | |
3137 | block->key.objectid = extent_key->offset; | |
3138 | block->key.offset = generation; | |
3139 | block->level = level; | |
3140 | block->key_ready = 0; | |
3141 | ||
3142 | rb_node = tree_insert(blocks, block->bytenr, &block->rb_node); | |
3143 | BUG_ON(rb_node); | |
3144 | ||
3145 | return 0; | |
3146 | } | |
3147 | ||
3148 | /* | |
3149 | * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY | |
3150 | */ | |
3151 | static int __add_tree_block(struct reloc_control *rc, | |
3152 | u64 bytenr, u32 blocksize, | |
3153 | struct rb_root *blocks) | |
3154 | { | |
3155 | struct btrfs_path *path; | |
3156 | struct btrfs_key key; | |
3157 | int ret; | |
3158 | ||
3159 | if (tree_block_processed(bytenr, blocksize, rc)) | |
3160 | return 0; | |
3161 | ||
3162 | if (tree_search(blocks, bytenr)) | |
3163 | return 0; | |
3164 | ||
3165 | path = btrfs_alloc_path(); | |
3166 | if (!path) | |
3167 | return -ENOMEM; | |
3168 | ||
3169 | key.objectid = bytenr; | |
3170 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
3171 | key.offset = blocksize; | |
3172 | ||
3173 | path->search_commit_root = 1; | |
3174 | path->skip_locking = 1; | |
3175 | ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 0, 0); | |
3176 | if (ret < 0) | |
3177 | goto out; | |
3178 | BUG_ON(ret); | |
3179 | ||
3180 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
3181 | ret = add_tree_block(rc, &key, path, blocks); | |
3182 | out: | |
3183 | btrfs_free_path(path); | |
3184 | return ret; | |
3185 | } | |
3186 | ||
3187 | /* | |
3188 | * helper to check if the block use full backrefs for pointers in it | |
3189 | */ | |
3190 | static int block_use_full_backref(struct reloc_control *rc, | |
3191 | struct extent_buffer *eb) | |
3192 | { | |
5d4f98a2 YZ |
3193 | u64 flags; |
3194 | int ret; | |
3195 | ||
3196 | if (btrfs_header_flag(eb, BTRFS_HEADER_FLAG_RELOC) || | |
3197 | btrfs_header_backref_rev(eb) < BTRFS_MIXED_BACKREF_REV) | |
3198 | return 1; | |
3199 | ||
3fd0a558 YZ |
3200 | ret = btrfs_lookup_extent_info(NULL, rc->extent_root, |
3201 | eb->start, eb->len, NULL, &flags); | |
5d4f98a2 YZ |
3202 | BUG_ON(ret); |
3203 | ||
5d4f98a2 YZ |
3204 | if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) |
3205 | ret = 1; | |
3206 | else | |
3207 | ret = 0; | |
5d4f98a2 YZ |
3208 | return ret; |
3209 | } | |
3210 | ||
0af3d00b JB |
3211 | static int delete_block_group_cache(struct btrfs_fs_info *fs_info, |
3212 | struct inode *inode, u64 ino) | |
3213 | { | |
3214 | struct btrfs_key key; | |
3215 | struct btrfs_path *path; | |
3216 | struct btrfs_root *root = fs_info->tree_root; | |
3217 | struct btrfs_trans_handle *trans; | |
3218 | unsigned long nr; | |
3219 | int ret = 0; | |
3220 | ||
3221 | if (inode) | |
3222 | goto truncate; | |
3223 | ||
3224 | key.objectid = ino; | |
3225 | key.type = BTRFS_INODE_ITEM_KEY; | |
3226 | key.offset = 0; | |
3227 | ||
3228 | inode = btrfs_iget(fs_info->sb, &key, root, NULL); | |
c704005d | 3229 | if (IS_ERR_OR_NULL(inode) || is_bad_inode(inode)) { |
0af3d00b JB |
3230 | if (inode && !IS_ERR(inode)) |
3231 | iput(inode); | |
3232 | return -ENOENT; | |
3233 | } | |
3234 | ||
3235 | truncate: | |
3236 | path = btrfs_alloc_path(); | |
3237 | if (!path) { | |
3238 | ret = -ENOMEM; | |
3239 | goto out; | |
3240 | } | |
3241 | ||
7a7eaa40 | 3242 | trans = btrfs_join_transaction(root); |
0af3d00b JB |
3243 | if (IS_ERR(trans)) { |
3244 | btrfs_free_path(path); | |
3612b495 | 3245 | ret = PTR_ERR(trans); |
0af3d00b JB |
3246 | goto out; |
3247 | } | |
3248 | ||
3249 | ret = btrfs_truncate_free_space_cache(root, trans, path, inode); | |
3250 | ||
3251 | btrfs_free_path(path); | |
3252 | nr = trans->blocks_used; | |
3253 | btrfs_end_transaction(trans, root); | |
3254 | btrfs_btree_balance_dirty(root, nr); | |
3255 | out: | |
3256 | iput(inode); | |
3257 | return ret; | |
3258 | } | |
3259 | ||
5d4f98a2 YZ |
3260 | /* |
3261 | * helper to add tree blocks for backref of type BTRFS_EXTENT_DATA_REF_KEY | |
3262 | * this function scans fs tree to find blocks reference the data extent | |
3263 | */ | |
3264 | static int find_data_references(struct reloc_control *rc, | |
3265 | struct btrfs_key *extent_key, | |
3266 | struct extent_buffer *leaf, | |
3267 | struct btrfs_extent_data_ref *ref, | |
3268 | struct rb_root *blocks) | |
3269 | { | |
3270 | struct btrfs_path *path; | |
3271 | struct tree_block *block; | |
3272 | struct btrfs_root *root; | |
3273 | struct btrfs_file_extent_item *fi; | |
3274 | struct rb_node *rb_node; | |
3275 | struct btrfs_key key; | |
3276 | u64 ref_root; | |
3277 | u64 ref_objectid; | |
3278 | u64 ref_offset; | |
3279 | u32 ref_count; | |
3280 | u32 nritems; | |
3281 | int err = 0; | |
3282 | int added = 0; | |
3283 | int counted; | |
3284 | int ret; | |
3285 | ||
5d4f98a2 YZ |
3286 | ref_root = btrfs_extent_data_ref_root(leaf, ref); |
3287 | ref_objectid = btrfs_extent_data_ref_objectid(leaf, ref); | |
3288 | ref_offset = btrfs_extent_data_ref_offset(leaf, ref); | |
3289 | ref_count = btrfs_extent_data_ref_count(leaf, ref); | |
3290 | ||
0af3d00b JB |
3291 | /* |
3292 | * This is an extent belonging to the free space cache, lets just delete | |
3293 | * it and redo the search. | |
3294 | */ | |
3295 | if (ref_root == BTRFS_ROOT_TREE_OBJECTID) { | |
3296 | ret = delete_block_group_cache(rc->extent_root->fs_info, | |
3297 | NULL, ref_objectid); | |
3298 | if (ret != -ENOENT) | |
3299 | return ret; | |
3300 | ret = 0; | |
3301 | } | |
3302 | ||
3303 | path = btrfs_alloc_path(); | |
3304 | if (!path) | |
3305 | return -ENOMEM; | |
026fd317 | 3306 | path->reada = 1; |
0af3d00b | 3307 | |
5d4f98a2 YZ |
3308 | root = read_fs_root(rc->extent_root->fs_info, ref_root); |
3309 | if (IS_ERR(root)) { | |
3310 | err = PTR_ERR(root); | |
3311 | goto out; | |
3312 | } | |
3313 | ||
3314 | key.objectid = ref_objectid; | |
3315 | key.offset = ref_offset; | |
3316 | key.type = BTRFS_EXTENT_DATA_KEY; | |
3317 | ||
3318 | path->search_commit_root = 1; | |
3319 | path->skip_locking = 1; | |
3320 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
3321 | if (ret < 0) { | |
3322 | err = ret; | |
3323 | goto out; | |
3324 | } | |
3325 | ||
3326 | leaf = path->nodes[0]; | |
3327 | nritems = btrfs_header_nritems(leaf); | |
3328 | /* | |
3329 | * the references in tree blocks that use full backrefs | |
3330 | * are not counted in | |
3331 | */ | |
3332 | if (block_use_full_backref(rc, leaf)) | |
3333 | counted = 0; | |
3334 | else | |
3335 | counted = 1; | |
3336 | rb_node = tree_search(blocks, leaf->start); | |
3337 | if (rb_node) { | |
3338 | if (counted) | |
3339 | added = 1; | |
3340 | else | |
3341 | path->slots[0] = nritems; | |
3342 | } | |
3343 | ||
3344 | while (ref_count > 0) { | |
3345 | while (path->slots[0] >= nritems) { | |
3346 | ret = btrfs_next_leaf(root, path); | |
3347 | if (ret < 0) { | |
3348 | err = ret; | |
3349 | goto out; | |
3350 | } | |
3351 | if (ret > 0) { | |
3352 | WARN_ON(1); | |
3353 | goto out; | |
3354 | } | |
3355 | ||
3356 | leaf = path->nodes[0]; | |
3357 | nritems = btrfs_header_nritems(leaf); | |
3358 | added = 0; | |
3359 | ||
3360 | if (block_use_full_backref(rc, leaf)) | |
3361 | counted = 0; | |
3362 | else | |
3363 | counted = 1; | |
3364 | rb_node = tree_search(blocks, leaf->start); | |
3365 | if (rb_node) { | |
3366 | if (counted) | |
3367 | added = 1; | |
3368 | else | |
3369 | path->slots[0] = nritems; | |
3370 | } | |
3371 | } | |
3372 | ||
3373 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
3374 | if (key.objectid != ref_objectid || | |
3375 | key.type != BTRFS_EXTENT_DATA_KEY) { | |
3376 | WARN_ON(1); | |
3377 | break; | |
3378 | } | |
3379 | ||
3380 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
3381 | struct btrfs_file_extent_item); | |
3382 | ||
3383 | if (btrfs_file_extent_type(leaf, fi) == | |
3384 | BTRFS_FILE_EXTENT_INLINE) | |
3385 | goto next; | |
3386 | ||
3387 | if (btrfs_file_extent_disk_bytenr(leaf, fi) != | |
3388 | extent_key->objectid) | |
3389 | goto next; | |
3390 | ||
3391 | key.offset -= btrfs_file_extent_offset(leaf, fi); | |
3392 | if (key.offset != ref_offset) | |
3393 | goto next; | |
3394 | ||
3395 | if (counted) | |
3396 | ref_count--; | |
3397 | if (added) | |
3398 | goto next; | |
3399 | ||
3400 | if (!tree_block_processed(leaf->start, leaf->len, rc)) { | |
3401 | block = kmalloc(sizeof(*block), GFP_NOFS); | |
3402 | if (!block) { | |
3403 | err = -ENOMEM; | |
3404 | break; | |
3405 | } | |
3406 | block->bytenr = leaf->start; | |
3407 | btrfs_item_key_to_cpu(leaf, &block->key, 0); | |
3408 | block->level = 0; | |
3409 | block->key_ready = 1; | |
3410 | rb_node = tree_insert(blocks, block->bytenr, | |
3411 | &block->rb_node); | |
3412 | BUG_ON(rb_node); | |
3413 | } | |
3414 | if (counted) | |
3415 | added = 1; | |
3416 | else | |
3417 | path->slots[0] = nritems; | |
3418 | next: | |
3419 | path->slots[0]++; | |
3420 | ||
3421 | } | |
3422 | out: | |
3423 | btrfs_free_path(path); | |
3424 | return err; | |
3425 | } | |
3426 | ||
3427 | /* | |
3428 | * hepler to find all tree blocks that reference a given data extent | |
3429 | */ | |
3430 | static noinline_for_stack | |
3431 | int add_data_references(struct reloc_control *rc, | |
3432 | struct btrfs_key *extent_key, | |
3433 | struct btrfs_path *path, | |
3434 | struct rb_root *blocks) | |
3435 | { | |
3436 | struct btrfs_key key; | |
3437 | struct extent_buffer *eb; | |
3438 | struct btrfs_extent_data_ref *dref; | |
3439 | struct btrfs_extent_inline_ref *iref; | |
3440 | unsigned long ptr; | |
3441 | unsigned long end; | |
3fd0a558 | 3442 | u32 blocksize = btrfs_level_size(rc->extent_root, 0); |
5d4f98a2 YZ |
3443 | int ret; |
3444 | int err = 0; | |
3445 | ||
5d4f98a2 YZ |
3446 | eb = path->nodes[0]; |
3447 | ptr = btrfs_item_ptr_offset(eb, path->slots[0]); | |
3448 | end = ptr + btrfs_item_size_nr(eb, path->slots[0]); | |
3449 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
3450 | if (ptr + sizeof(struct btrfs_extent_item_v0) == end) | |
3451 | ptr = end; | |
3452 | else | |
3453 | #endif | |
3454 | ptr += sizeof(struct btrfs_extent_item); | |
3455 | ||
3456 | while (ptr < end) { | |
3457 | iref = (struct btrfs_extent_inline_ref *)ptr; | |
3458 | key.type = btrfs_extent_inline_ref_type(eb, iref); | |
3459 | if (key.type == BTRFS_SHARED_DATA_REF_KEY) { | |
3460 | key.offset = btrfs_extent_inline_ref_offset(eb, iref); | |
3461 | ret = __add_tree_block(rc, key.offset, blocksize, | |
3462 | blocks); | |
3463 | } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { | |
3464 | dref = (struct btrfs_extent_data_ref *)(&iref->offset); | |
3465 | ret = find_data_references(rc, extent_key, | |
3466 | eb, dref, blocks); | |
3467 | } else { | |
3468 | BUG(); | |
3469 | } | |
3470 | ptr += btrfs_extent_inline_ref_size(key.type); | |
3471 | } | |
3472 | WARN_ON(ptr > end); | |
3473 | ||
3474 | while (1) { | |
3475 | cond_resched(); | |
3476 | eb = path->nodes[0]; | |
3477 | if (path->slots[0] >= btrfs_header_nritems(eb)) { | |
3478 | ret = btrfs_next_leaf(rc->extent_root, path); | |
3479 | if (ret < 0) { | |
3480 | err = ret; | |
3481 | break; | |
3482 | } | |
3483 | if (ret > 0) | |
3484 | break; | |
3485 | eb = path->nodes[0]; | |
3486 | } | |
3487 | ||
3488 | btrfs_item_key_to_cpu(eb, &key, path->slots[0]); | |
3489 | if (key.objectid != extent_key->objectid) | |
3490 | break; | |
3491 | ||
3492 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
3493 | if (key.type == BTRFS_SHARED_DATA_REF_KEY || | |
3494 | key.type == BTRFS_EXTENT_REF_V0_KEY) { | |
3495 | #else | |
3496 | BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY); | |
3497 | if (key.type == BTRFS_SHARED_DATA_REF_KEY) { | |
3498 | #endif | |
3499 | ret = __add_tree_block(rc, key.offset, blocksize, | |
3500 | blocks); | |
3501 | } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { | |
3502 | dref = btrfs_item_ptr(eb, path->slots[0], | |
3503 | struct btrfs_extent_data_ref); | |
3504 | ret = find_data_references(rc, extent_key, | |
3505 | eb, dref, blocks); | |
3506 | } else { | |
3507 | ret = 0; | |
3508 | } | |
3509 | if (ret) { | |
3510 | err = ret; | |
3511 | break; | |
3512 | } | |
3513 | path->slots[0]++; | |
3514 | } | |
b3b4aa74 | 3515 | btrfs_release_path(path); |
5d4f98a2 YZ |
3516 | if (err) |
3517 | free_block_list(blocks); | |
3518 | return err; | |
3519 | } | |
3520 | ||
3521 | /* | |
3522 | * hepler to find next unprocessed extent | |
3523 | */ | |
3524 | static noinline_for_stack | |
3525 | int find_next_extent(struct btrfs_trans_handle *trans, | |
3fd0a558 YZ |
3526 | struct reloc_control *rc, struct btrfs_path *path, |
3527 | struct btrfs_key *extent_key) | |
5d4f98a2 YZ |
3528 | { |
3529 | struct btrfs_key key; | |
3530 | struct extent_buffer *leaf; | |
3531 | u64 start, end, last; | |
3532 | int ret; | |
3533 | ||
3534 | last = rc->block_group->key.objectid + rc->block_group->key.offset; | |
3535 | while (1) { | |
3536 | cond_resched(); | |
3537 | if (rc->search_start >= last) { | |
3538 | ret = 1; | |
3539 | break; | |
3540 | } | |
3541 | ||
3542 | key.objectid = rc->search_start; | |
3543 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
3544 | key.offset = 0; | |
3545 | ||
3546 | path->search_commit_root = 1; | |
3547 | path->skip_locking = 1; | |
3548 | ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, | |
3549 | 0, 0); | |
3550 | if (ret < 0) | |
3551 | break; | |
3552 | next: | |
3553 | leaf = path->nodes[0]; | |
3554 | if (path->slots[0] >= btrfs_header_nritems(leaf)) { | |
3555 | ret = btrfs_next_leaf(rc->extent_root, path); | |
3556 | if (ret != 0) | |
3557 | break; | |
3558 | leaf = path->nodes[0]; | |
3559 | } | |
3560 | ||
3561 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
3562 | if (key.objectid >= last) { | |
3563 | ret = 1; | |
3564 | break; | |
3565 | } | |
3566 | ||
3567 | if (key.type != BTRFS_EXTENT_ITEM_KEY || | |
3568 | key.objectid + key.offset <= rc->search_start) { | |
3569 | path->slots[0]++; | |
3570 | goto next; | |
3571 | } | |
3572 | ||
3573 | ret = find_first_extent_bit(&rc->processed_blocks, | |
3574 | key.objectid, &start, &end, | |
3575 | EXTENT_DIRTY); | |
3576 | ||
3577 | if (ret == 0 && start <= key.objectid) { | |
b3b4aa74 | 3578 | btrfs_release_path(path); |
5d4f98a2 YZ |
3579 | rc->search_start = end + 1; |
3580 | } else { | |
3581 | rc->search_start = key.objectid + key.offset; | |
3fd0a558 | 3582 | memcpy(extent_key, &key, sizeof(key)); |
5d4f98a2 YZ |
3583 | return 0; |
3584 | } | |
3585 | } | |
b3b4aa74 | 3586 | btrfs_release_path(path); |
5d4f98a2 YZ |
3587 | return ret; |
3588 | } | |
3589 | ||
3590 | static void set_reloc_control(struct reloc_control *rc) | |
3591 | { | |
3592 | struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; | |
a4abeea4 | 3593 | spin_lock(&fs_info->trans_lock); |
5d4f98a2 | 3594 | fs_info->reloc_ctl = rc; |
a4abeea4 | 3595 | spin_unlock(&fs_info->trans_lock); |
5d4f98a2 YZ |
3596 | } |
3597 | ||
3598 | static void unset_reloc_control(struct reloc_control *rc) | |
3599 | { | |
3600 | struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; | |
a4abeea4 | 3601 | spin_lock(&fs_info->trans_lock); |
5d4f98a2 | 3602 | fs_info->reloc_ctl = NULL; |
a4abeea4 | 3603 | spin_unlock(&fs_info->trans_lock); |
5d4f98a2 YZ |
3604 | } |
3605 | ||
3606 | static int check_extent_flags(u64 flags) | |
3607 | { | |
3608 | if ((flags & BTRFS_EXTENT_FLAG_DATA) && | |
3609 | (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) | |
3610 | return 1; | |
3611 | if (!(flags & BTRFS_EXTENT_FLAG_DATA) && | |
3612 | !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) | |
3613 | return 1; | |
3614 | if ((flags & BTRFS_EXTENT_FLAG_DATA) && | |
3615 | (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) | |
3616 | return 1; | |
3617 | return 0; | |
3618 | } | |
3619 | ||
3fd0a558 YZ |
3620 | static noinline_for_stack |
3621 | int prepare_to_relocate(struct reloc_control *rc) | |
3622 | { | |
3623 | struct btrfs_trans_handle *trans; | |
3624 | int ret; | |
3625 | ||
3626 | rc->block_rsv = btrfs_alloc_block_rsv(rc->extent_root); | |
3627 | if (!rc->block_rsv) | |
3628 | return -ENOMEM; | |
3629 | ||
3630 | /* | |
3631 | * reserve some space for creating reloc trees. | |
3632 | * btrfs_init_reloc_root will use them when there | |
3633 | * is no reservation in transaction handle. | |
3634 | */ | |
3635 | ret = btrfs_block_rsv_add(NULL, rc->extent_root, rc->block_rsv, | |
8bb8ab2e | 3636 | rc->extent_root->nodesize * 256); |
3fd0a558 YZ |
3637 | if (ret) |
3638 | return ret; | |
3639 | ||
3640 | rc->block_rsv->refill_used = 1; | |
3641 | btrfs_add_durable_block_rsv(rc->extent_root->fs_info, rc->block_rsv); | |
3642 | ||
3643 | memset(&rc->cluster, 0, sizeof(rc->cluster)); | |
3644 | rc->search_start = rc->block_group->key.objectid; | |
3645 | rc->extents_found = 0; | |
3646 | rc->nodes_relocated = 0; | |
3647 | rc->merging_rsv_size = 0; | |
3fd0a558 YZ |
3648 | |
3649 | rc->create_reloc_tree = 1; | |
3650 | set_reloc_control(rc); | |
3651 | ||
7a7eaa40 | 3652 | trans = btrfs_join_transaction(rc->extent_root); |
3612b495 | 3653 | BUG_ON(IS_ERR(trans)); |
3fd0a558 YZ |
3654 | btrfs_commit_transaction(trans, rc->extent_root); |
3655 | return 0; | |
3656 | } | |
76dda93c | 3657 | |
5d4f98a2 YZ |
3658 | static noinline_for_stack int relocate_block_group(struct reloc_control *rc) |
3659 | { | |
3660 | struct rb_root blocks = RB_ROOT; | |
3661 | struct btrfs_key key; | |
3662 | struct btrfs_trans_handle *trans = NULL; | |
3663 | struct btrfs_path *path; | |
3664 | struct btrfs_extent_item *ei; | |
3665 | unsigned long nr; | |
3666 | u64 flags; | |
3667 | u32 item_size; | |
3668 | int ret; | |
3669 | int err = 0; | |
c87f08ca | 3670 | int progress = 0; |
5d4f98a2 YZ |
3671 | |
3672 | path = btrfs_alloc_path(); | |
3fd0a558 | 3673 | if (!path) |
5d4f98a2 | 3674 | return -ENOMEM; |
026fd317 | 3675 | path->reada = 1; |
5d4f98a2 | 3676 | |
3fd0a558 YZ |
3677 | ret = prepare_to_relocate(rc); |
3678 | if (ret) { | |
3679 | err = ret; | |
3680 | goto out_free; | |
3681 | } | |
5d4f98a2 YZ |
3682 | |
3683 | while (1) { | |
c87f08ca | 3684 | progress++; |
a22285a6 | 3685 | trans = btrfs_start_transaction(rc->extent_root, 0); |
98d5dc13 | 3686 | BUG_ON(IS_ERR(trans)); |
c87f08ca | 3687 | restart: |
3fd0a558 YZ |
3688 | if (update_backref_cache(trans, &rc->backref_cache)) { |
3689 | btrfs_end_transaction(trans, rc->extent_root); | |
3690 | continue; | |
3691 | } | |
3692 | ||
3693 | ret = find_next_extent(trans, rc, path, &key); | |
5d4f98a2 YZ |
3694 | if (ret < 0) |
3695 | err = ret; | |
3696 | if (ret != 0) | |
3697 | break; | |
3698 | ||
3699 | rc->extents_found++; | |
3700 | ||
3701 | ei = btrfs_item_ptr(path->nodes[0], path->slots[0], | |
3702 | struct btrfs_extent_item); | |
3fd0a558 | 3703 | item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]); |
5d4f98a2 YZ |
3704 | if (item_size >= sizeof(*ei)) { |
3705 | flags = btrfs_extent_flags(path->nodes[0], ei); | |
3706 | ret = check_extent_flags(flags); | |
3707 | BUG_ON(ret); | |
3708 | ||
3709 | } else { | |
3710 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
3711 | u64 ref_owner; | |
3712 | int path_change = 0; | |
3713 | ||
3714 | BUG_ON(item_size != | |
3715 | sizeof(struct btrfs_extent_item_v0)); | |
3716 | ret = get_ref_objectid_v0(rc, path, &key, &ref_owner, | |
3717 | &path_change); | |
3718 | if (ref_owner < BTRFS_FIRST_FREE_OBJECTID) | |
3719 | flags = BTRFS_EXTENT_FLAG_TREE_BLOCK; | |
3720 | else | |
3721 | flags = BTRFS_EXTENT_FLAG_DATA; | |
3722 | ||
3723 | if (path_change) { | |
b3b4aa74 | 3724 | btrfs_release_path(path); |
5d4f98a2 YZ |
3725 | |
3726 | path->search_commit_root = 1; | |
3727 | path->skip_locking = 1; | |
3728 | ret = btrfs_search_slot(NULL, rc->extent_root, | |
3729 | &key, path, 0, 0); | |
3730 | if (ret < 0) { | |
3731 | err = ret; | |
3732 | break; | |
3733 | } | |
3734 | BUG_ON(ret > 0); | |
3735 | } | |
3736 | #else | |
3737 | BUG(); | |
3738 | #endif | |
3739 | } | |
3740 | ||
3741 | if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { | |
3742 | ret = add_tree_block(rc, &key, path, &blocks); | |
3743 | } else if (rc->stage == UPDATE_DATA_PTRS && | |
3fd0a558 | 3744 | (flags & BTRFS_EXTENT_FLAG_DATA)) { |
5d4f98a2 YZ |
3745 | ret = add_data_references(rc, &key, path, &blocks); |
3746 | } else { | |
b3b4aa74 | 3747 | btrfs_release_path(path); |
5d4f98a2 YZ |
3748 | ret = 0; |
3749 | } | |
3750 | if (ret < 0) { | |
3fd0a558 | 3751 | err = ret; |
5d4f98a2 YZ |
3752 | break; |
3753 | } | |
3754 | ||
3755 | if (!RB_EMPTY_ROOT(&blocks)) { | |
3756 | ret = relocate_tree_blocks(trans, rc, &blocks); | |
3757 | if (ret < 0) { | |
3fd0a558 YZ |
3758 | if (ret != -EAGAIN) { |
3759 | err = ret; | |
3760 | break; | |
3761 | } | |
3762 | rc->extents_found--; | |
3763 | rc->search_start = key.objectid; | |
3764 | } | |
3765 | } | |
3766 | ||
3767 | ret = btrfs_block_rsv_check(trans, rc->extent_root, | |
3768 | rc->block_rsv, 0, 5); | |
3769 | if (ret < 0) { | |
3770 | if (ret != -EAGAIN) { | |
5d4f98a2 | 3771 | err = ret; |
3fd0a558 | 3772 | WARN_ON(1); |
5d4f98a2 YZ |
3773 | break; |
3774 | } | |
3fd0a558 | 3775 | rc->commit_transaction = 1; |
5d4f98a2 YZ |
3776 | } |
3777 | ||
3fd0a558 YZ |
3778 | if (rc->commit_transaction) { |
3779 | rc->commit_transaction = 0; | |
3780 | ret = btrfs_commit_transaction(trans, rc->extent_root); | |
3781 | BUG_ON(ret); | |
3782 | } else { | |
3783 | nr = trans->blocks_used; | |
3784 | btrfs_end_transaction_throttle(trans, rc->extent_root); | |
3785 | btrfs_btree_balance_dirty(rc->extent_root, nr); | |
3786 | } | |
5d4f98a2 | 3787 | trans = NULL; |
5d4f98a2 YZ |
3788 | |
3789 | if (rc->stage == MOVE_DATA_EXTENTS && | |
3790 | (flags & BTRFS_EXTENT_FLAG_DATA)) { | |
3791 | rc->found_file_extent = 1; | |
0257bb82 | 3792 | ret = relocate_data_extent(rc->data_inode, |
3fd0a558 | 3793 | &key, &rc->cluster); |
5d4f98a2 YZ |
3794 | if (ret < 0) { |
3795 | err = ret; | |
3796 | break; | |
3797 | } | |
3798 | } | |
3799 | } | |
c87f08ca CM |
3800 | if (trans && progress && err == -ENOSPC) { |
3801 | ret = btrfs_force_chunk_alloc(trans, rc->extent_root, | |
3802 | rc->block_group->flags); | |
3803 | if (ret == 0) { | |
3804 | err = 0; | |
3805 | progress = 0; | |
3806 | goto restart; | |
3807 | } | |
3808 | } | |
3fd0a558 | 3809 | |
b3b4aa74 | 3810 | btrfs_release_path(path); |
3fd0a558 YZ |
3811 | clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY, |
3812 | GFP_NOFS); | |
5d4f98a2 YZ |
3813 | |
3814 | if (trans) { | |
3815 | nr = trans->blocks_used; | |
3fd0a558 | 3816 | btrfs_end_transaction_throttle(trans, rc->extent_root); |
5d4f98a2 YZ |
3817 | btrfs_btree_balance_dirty(rc->extent_root, nr); |
3818 | } | |
3819 | ||
0257bb82 | 3820 | if (!err) { |
3fd0a558 YZ |
3821 | ret = relocate_file_extent_cluster(rc->data_inode, |
3822 | &rc->cluster); | |
0257bb82 YZ |
3823 | if (ret < 0) |
3824 | err = ret; | |
3825 | } | |
3826 | ||
3fd0a558 YZ |
3827 | rc->create_reloc_tree = 0; |
3828 | set_reloc_control(rc); | |
0257bb82 | 3829 | |
3fd0a558 YZ |
3830 | backref_cache_cleanup(&rc->backref_cache); |
3831 | btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, (u64)-1); | |
5d4f98a2 | 3832 | |
3fd0a558 | 3833 | err = prepare_to_merge(rc, err); |
5d4f98a2 YZ |
3834 | |
3835 | merge_reloc_roots(rc); | |
3836 | ||
3fd0a558 | 3837 | rc->merge_reloc_tree = 0; |
5d4f98a2 | 3838 | unset_reloc_control(rc); |
3fd0a558 | 3839 | btrfs_block_rsv_release(rc->extent_root, rc->block_rsv, (u64)-1); |
5d4f98a2 YZ |
3840 | |
3841 | /* get rid of pinned extents */ | |
7a7eaa40 | 3842 | trans = btrfs_join_transaction(rc->extent_root); |
3612b495 TI |
3843 | if (IS_ERR(trans)) |
3844 | err = PTR_ERR(trans); | |
3845 | else | |
3846 | btrfs_commit_transaction(trans, rc->extent_root); | |
3fd0a558 YZ |
3847 | out_free: |
3848 | btrfs_free_block_rsv(rc->extent_root, rc->block_rsv); | |
3849 | btrfs_free_path(path); | |
5d4f98a2 YZ |
3850 | return err; |
3851 | } | |
3852 | ||
3853 | static int __insert_orphan_inode(struct btrfs_trans_handle *trans, | |
0257bb82 | 3854 | struct btrfs_root *root, u64 objectid) |
5d4f98a2 YZ |
3855 | { |
3856 | struct btrfs_path *path; | |
3857 | struct btrfs_inode_item *item; | |
3858 | struct extent_buffer *leaf; | |
3859 | int ret; | |
3860 | ||
3861 | path = btrfs_alloc_path(); | |
3862 | if (!path) | |
3863 | return -ENOMEM; | |
3864 | ||
3865 | ret = btrfs_insert_empty_inode(trans, root, path, objectid); | |
3866 | if (ret) | |
3867 | goto out; | |
3868 | ||
3869 | leaf = path->nodes[0]; | |
3870 | item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); | |
3871 | memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); | |
3872 | btrfs_set_inode_generation(leaf, item, 1); | |
0257bb82 | 3873 | btrfs_set_inode_size(leaf, item, 0); |
5d4f98a2 | 3874 | btrfs_set_inode_mode(leaf, item, S_IFREG | 0600); |
3fd0a558 YZ |
3875 | btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS | |
3876 | BTRFS_INODE_PREALLOC); | |
5d4f98a2 | 3877 | btrfs_mark_buffer_dirty(leaf); |
b3b4aa74 | 3878 | btrfs_release_path(path); |
5d4f98a2 YZ |
3879 | out: |
3880 | btrfs_free_path(path); | |
3881 | return ret; | |
3882 | } | |
3883 | ||
3884 | /* | |
3885 | * helper to create inode for data relocation. | |
3886 | * the inode is in data relocation tree and its link count is 0 | |
3887 | */ | |
3fd0a558 YZ |
3888 | static noinline_for_stack |
3889 | struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info, | |
3890 | struct btrfs_block_group_cache *group) | |
5d4f98a2 YZ |
3891 | { |
3892 | struct inode *inode = NULL; | |
3893 | struct btrfs_trans_handle *trans; | |
3894 | struct btrfs_root *root; | |
3895 | struct btrfs_key key; | |
3896 | unsigned long nr; | |
3897 | u64 objectid = BTRFS_FIRST_FREE_OBJECTID; | |
3898 | int err = 0; | |
3899 | ||
3900 | root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); | |
3901 | if (IS_ERR(root)) | |
3902 | return ERR_CAST(root); | |
3903 | ||
a22285a6 | 3904 | trans = btrfs_start_transaction(root, 6); |
3fd0a558 YZ |
3905 | if (IS_ERR(trans)) |
3906 | return ERR_CAST(trans); | |
5d4f98a2 | 3907 | |
581bb050 | 3908 | err = btrfs_find_free_objectid(root, &objectid); |
5d4f98a2 YZ |
3909 | if (err) |
3910 | goto out; | |
3911 | ||
0257bb82 | 3912 | err = __insert_orphan_inode(trans, root, objectid); |
5d4f98a2 YZ |
3913 | BUG_ON(err); |
3914 | ||
3915 | key.objectid = objectid; | |
3916 | key.type = BTRFS_INODE_ITEM_KEY; | |
3917 | key.offset = 0; | |
73f73415 | 3918 | inode = btrfs_iget(root->fs_info->sb, &key, root, NULL); |
5d4f98a2 YZ |
3919 | BUG_ON(IS_ERR(inode) || is_bad_inode(inode)); |
3920 | BTRFS_I(inode)->index_cnt = group->key.objectid; | |
3921 | ||
3922 | err = btrfs_orphan_add(trans, inode); | |
3923 | out: | |
3924 | nr = trans->blocks_used; | |
3925 | btrfs_end_transaction(trans, root); | |
5d4f98a2 YZ |
3926 | btrfs_btree_balance_dirty(root, nr); |
3927 | if (err) { | |
3928 | if (inode) | |
3929 | iput(inode); | |
3930 | inode = ERR_PTR(err); | |
3931 | } | |
3932 | return inode; | |
3933 | } | |
3934 | ||
3fd0a558 YZ |
3935 | static struct reloc_control *alloc_reloc_control(void) |
3936 | { | |
3937 | struct reloc_control *rc; | |
3938 | ||
3939 | rc = kzalloc(sizeof(*rc), GFP_NOFS); | |
3940 | if (!rc) | |
3941 | return NULL; | |
3942 | ||
3943 | INIT_LIST_HEAD(&rc->reloc_roots); | |
3944 | backref_cache_init(&rc->backref_cache); | |
3945 | mapping_tree_init(&rc->reloc_root_tree); | |
f993c883 | 3946 | extent_io_tree_init(&rc->processed_blocks, NULL); |
3fd0a558 YZ |
3947 | return rc; |
3948 | } | |
3949 | ||
5d4f98a2 YZ |
3950 | /* |
3951 | * function to relocate all extents in a block group. | |
3952 | */ | |
3953 | int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start) | |
3954 | { | |
3955 | struct btrfs_fs_info *fs_info = extent_root->fs_info; | |
3956 | struct reloc_control *rc; | |
0af3d00b JB |
3957 | struct inode *inode; |
3958 | struct btrfs_path *path; | |
5d4f98a2 | 3959 | int ret; |
f0486c68 | 3960 | int rw = 0; |
5d4f98a2 YZ |
3961 | int err = 0; |
3962 | ||
3fd0a558 | 3963 | rc = alloc_reloc_control(); |
5d4f98a2 YZ |
3964 | if (!rc) |
3965 | return -ENOMEM; | |
3966 | ||
f0486c68 | 3967 | rc->extent_root = extent_root; |
3fd0a558 | 3968 | |
5d4f98a2 YZ |
3969 | rc->block_group = btrfs_lookup_block_group(fs_info, group_start); |
3970 | BUG_ON(!rc->block_group); | |
3971 | ||
f0486c68 YZ |
3972 | if (!rc->block_group->ro) { |
3973 | ret = btrfs_set_block_group_ro(extent_root, rc->block_group); | |
3974 | if (ret) { | |
3975 | err = ret; | |
3976 | goto out; | |
3977 | } | |
3978 | rw = 1; | |
3979 | } | |
3980 | ||
0af3d00b JB |
3981 | path = btrfs_alloc_path(); |
3982 | if (!path) { | |
3983 | err = -ENOMEM; | |
3984 | goto out; | |
3985 | } | |
3986 | ||
3987 | inode = lookup_free_space_inode(fs_info->tree_root, rc->block_group, | |
3988 | path); | |
3989 | btrfs_free_path(path); | |
3990 | ||
3991 | if (!IS_ERR(inode)) | |
3992 | ret = delete_block_group_cache(fs_info, inode, 0); | |
3993 | else | |
3994 | ret = PTR_ERR(inode); | |
3995 | ||
3996 | if (ret && ret != -ENOENT) { | |
3997 | err = ret; | |
3998 | goto out; | |
3999 | } | |
4000 | ||
5d4f98a2 YZ |
4001 | rc->data_inode = create_reloc_inode(fs_info, rc->block_group); |
4002 | if (IS_ERR(rc->data_inode)) { | |
4003 | err = PTR_ERR(rc->data_inode); | |
4004 | rc->data_inode = NULL; | |
4005 | goto out; | |
4006 | } | |
4007 | ||
4008 | printk(KERN_INFO "btrfs: relocating block group %llu flags %llu\n", | |
4009 | (unsigned long long)rc->block_group->key.objectid, | |
4010 | (unsigned long long)rc->block_group->flags); | |
4011 | ||
24bbcf04 YZ |
4012 | btrfs_start_delalloc_inodes(fs_info->tree_root, 0); |
4013 | btrfs_wait_ordered_extents(fs_info->tree_root, 0, 0); | |
5d4f98a2 YZ |
4014 | |
4015 | while (1) { | |
76dda93c YZ |
4016 | mutex_lock(&fs_info->cleaner_mutex); |
4017 | ||
4018 | btrfs_clean_old_snapshots(fs_info->tree_root); | |
5d4f98a2 | 4019 | ret = relocate_block_group(rc); |
76dda93c YZ |
4020 | |
4021 | mutex_unlock(&fs_info->cleaner_mutex); | |
5d4f98a2 YZ |
4022 | if (ret < 0) { |
4023 | err = ret; | |
3fd0a558 | 4024 | goto out; |
5d4f98a2 YZ |
4025 | } |
4026 | ||
4027 | if (rc->extents_found == 0) | |
4028 | break; | |
4029 | ||
4030 | printk(KERN_INFO "btrfs: found %llu extents\n", | |
4031 | (unsigned long long)rc->extents_found); | |
4032 | ||
4033 | if (rc->stage == MOVE_DATA_EXTENTS && rc->found_file_extent) { | |
4034 | btrfs_wait_ordered_range(rc->data_inode, 0, (u64)-1); | |
4035 | invalidate_mapping_pages(rc->data_inode->i_mapping, | |
4036 | 0, -1); | |
4037 | rc->stage = UPDATE_DATA_PTRS; | |
5d4f98a2 YZ |
4038 | } |
4039 | } | |
4040 | ||
0257bb82 YZ |
4041 | filemap_write_and_wait_range(fs_info->btree_inode->i_mapping, |
4042 | rc->block_group->key.objectid, | |
4043 | rc->block_group->key.objectid + | |
4044 | rc->block_group->key.offset - 1); | |
5d4f98a2 YZ |
4045 | |
4046 | WARN_ON(rc->block_group->pinned > 0); | |
4047 | WARN_ON(rc->block_group->reserved > 0); | |
4048 | WARN_ON(btrfs_block_group_used(&rc->block_group->item) > 0); | |
4049 | out: | |
f0486c68 YZ |
4050 | if (err && rw) |
4051 | btrfs_set_block_group_rw(extent_root, rc->block_group); | |
5d4f98a2 | 4052 | iput(rc->data_inode); |
5d4f98a2 YZ |
4053 | btrfs_put_block_group(rc->block_group); |
4054 | kfree(rc); | |
4055 | return err; | |
4056 | } | |
4057 | ||
76dda93c YZ |
4058 | static noinline_for_stack int mark_garbage_root(struct btrfs_root *root) |
4059 | { | |
4060 | struct btrfs_trans_handle *trans; | |
4061 | int ret; | |
4062 | ||
a22285a6 | 4063 | trans = btrfs_start_transaction(root->fs_info->tree_root, 0); |
98d5dc13 | 4064 | BUG_ON(IS_ERR(trans)); |
76dda93c YZ |
4065 | |
4066 | memset(&root->root_item.drop_progress, 0, | |
4067 | sizeof(root->root_item.drop_progress)); | |
4068 | root->root_item.drop_level = 0; | |
4069 | btrfs_set_root_refs(&root->root_item, 0); | |
4070 | ret = btrfs_update_root(trans, root->fs_info->tree_root, | |
4071 | &root->root_key, &root->root_item); | |
4072 | BUG_ON(ret); | |
4073 | ||
4074 | ret = btrfs_end_transaction(trans, root->fs_info->tree_root); | |
4075 | BUG_ON(ret); | |
4076 | return 0; | |
4077 | } | |
4078 | ||
5d4f98a2 YZ |
4079 | /* |
4080 | * recover relocation interrupted by system crash. | |
4081 | * | |
4082 | * this function resumes merging reloc trees with corresponding fs trees. | |
4083 | * this is important for keeping the sharing of tree blocks | |
4084 | */ | |
4085 | int btrfs_recover_relocation(struct btrfs_root *root) | |
4086 | { | |
4087 | LIST_HEAD(reloc_roots); | |
4088 | struct btrfs_key key; | |
4089 | struct btrfs_root *fs_root; | |
4090 | struct btrfs_root *reloc_root; | |
4091 | struct btrfs_path *path; | |
4092 | struct extent_buffer *leaf; | |
4093 | struct reloc_control *rc = NULL; | |
4094 | struct btrfs_trans_handle *trans; | |
4095 | int ret; | |
4096 | int err = 0; | |
4097 | ||
4098 | path = btrfs_alloc_path(); | |
4099 | if (!path) | |
4100 | return -ENOMEM; | |
026fd317 | 4101 | path->reada = -1; |
5d4f98a2 YZ |
4102 | |
4103 | key.objectid = BTRFS_TREE_RELOC_OBJECTID; | |
4104 | key.type = BTRFS_ROOT_ITEM_KEY; | |
4105 | key.offset = (u64)-1; | |
4106 | ||
4107 | while (1) { | |
4108 | ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, | |
4109 | path, 0, 0); | |
4110 | if (ret < 0) { | |
4111 | err = ret; | |
4112 | goto out; | |
4113 | } | |
4114 | if (ret > 0) { | |
4115 | if (path->slots[0] == 0) | |
4116 | break; | |
4117 | path->slots[0]--; | |
4118 | } | |
4119 | leaf = path->nodes[0]; | |
4120 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
b3b4aa74 | 4121 | btrfs_release_path(path); |
5d4f98a2 YZ |
4122 | |
4123 | if (key.objectid != BTRFS_TREE_RELOC_OBJECTID || | |
4124 | key.type != BTRFS_ROOT_ITEM_KEY) | |
4125 | break; | |
4126 | ||
4127 | reloc_root = btrfs_read_fs_root_no_radix(root, &key); | |
4128 | if (IS_ERR(reloc_root)) { | |
4129 | err = PTR_ERR(reloc_root); | |
4130 | goto out; | |
4131 | } | |
4132 | ||
4133 | list_add(&reloc_root->root_list, &reloc_roots); | |
4134 | ||
4135 | if (btrfs_root_refs(&reloc_root->root_item) > 0) { | |
4136 | fs_root = read_fs_root(root->fs_info, | |
4137 | reloc_root->root_key.offset); | |
4138 | if (IS_ERR(fs_root)) { | |
76dda93c YZ |
4139 | ret = PTR_ERR(fs_root); |
4140 | if (ret != -ENOENT) { | |
4141 | err = ret; | |
4142 | goto out; | |
4143 | } | |
4144 | mark_garbage_root(reloc_root); | |
5d4f98a2 YZ |
4145 | } |
4146 | } | |
4147 | ||
4148 | if (key.offset == 0) | |
4149 | break; | |
4150 | ||
4151 | key.offset--; | |
4152 | } | |
b3b4aa74 | 4153 | btrfs_release_path(path); |
5d4f98a2 YZ |
4154 | |
4155 | if (list_empty(&reloc_roots)) | |
4156 | goto out; | |
4157 | ||
3fd0a558 | 4158 | rc = alloc_reloc_control(); |
5d4f98a2 YZ |
4159 | if (!rc) { |
4160 | err = -ENOMEM; | |
4161 | goto out; | |
4162 | } | |
4163 | ||
5d4f98a2 YZ |
4164 | rc->extent_root = root->fs_info->extent_root; |
4165 | ||
4166 | set_reloc_control(rc); | |
4167 | ||
7a7eaa40 | 4168 | trans = btrfs_join_transaction(rc->extent_root); |
3612b495 TI |
4169 | if (IS_ERR(trans)) { |
4170 | unset_reloc_control(rc); | |
4171 | err = PTR_ERR(trans); | |
4172 | goto out_free; | |
4173 | } | |
3fd0a558 YZ |
4174 | |
4175 | rc->merge_reloc_tree = 1; | |
4176 | ||
5d4f98a2 YZ |
4177 | while (!list_empty(&reloc_roots)) { |
4178 | reloc_root = list_entry(reloc_roots.next, | |
4179 | struct btrfs_root, root_list); | |
4180 | list_del(&reloc_root->root_list); | |
4181 | ||
4182 | if (btrfs_root_refs(&reloc_root->root_item) == 0) { | |
4183 | list_add_tail(&reloc_root->root_list, | |
4184 | &rc->reloc_roots); | |
4185 | continue; | |
4186 | } | |
4187 | ||
4188 | fs_root = read_fs_root(root->fs_info, | |
4189 | reloc_root->root_key.offset); | |
4190 | BUG_ON(IS_ERR(fs_root)); | |
4191 | ||
4192 | __add_reloc_root(reloc_root); | |
4193 | fs_root->reloc_root = reloc_root; | |
4194 | } | |
4195 | ||
5d4f98a2 YZ |
4196 | btrfs_commit_transaction(trans, rc->extent_root); |
4197 | ||
4198 | merge_reloc_roots(rc); | |
4199 | ||
4200 | unset_reloc_control(rc); | |
4201 | ||
7a7eaa40 | 4202 | trans = btrfs_join_transaction(rc->extent_root); |
3612b495 TI |
4203 | if (IS_ERR(trans)) |
4204 | err = PTR_ERR(trans); | |
4205 | else | |
4206 | btrfs_commit_transaction(trans, rc->extent_root); | |
4207 | out_free: | |
3fd0a558 | 4208 | kfree(rc); |
3612b495 | 4209 | out: |
5d4f98a2 YZ |
4210 | while (!list_empty(&reloc_roots)) { |
4211 | reloc_root = list_entry(reloc_roots.next, | |
4212 | struct btrfs_root, root_list); | |
4213 | list_del(&reloc_root->root_list); | |
4214 | free_extent_buffer(reloc_root->node); | |
4215 | free_extent_buffer(reloc_root->commit_root); | |
4216 | kfree(reloc_root); | |
4217 | } | |
4218 | btrfs_free_path(path); | |
4219 | ||
4220 | if (err == 0) { | |
4221 | /* cleanup orphan inode in data relocation tree */ | |
4222 | fs_root = read_fs_root(root->fs_info, | |
4223 | BTRFS_DATA_RELOC_TREE_OBJECTID); | |
4224 | if (IS_ERR(fs_root)) | |
4225 | err = PTR_ERR(fs_root); | |
d7ce5843 | 4226 | else |
66b4ffd1 | 4227 | err = btrfs_orphan_cleanup(fs_root); |
5d4f98a2 YZ |
4228 | } |
4229 | return err; | |
4230 | } | |
4231 | ||
4232 | /* | |
4233 | * helper to add ordered checksum for data relocation. | |
4234 | * | |
4235 | * cloning checksum properly handles the nodatasum extents. | |
4236 | * it also saves CPU time to re-calculate the checksum. | |
4237 | */ | |
4238 | int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) | |
4239 | { | |
4240 | struct btrfs_ordered_sum *sums; | |
4241 | struct btrfs_sector_sum *sector_sum; | |
4242 | struct btrfs_ordered_extent *ordered; | |
4243 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
4244 | size_t offset; | |
4245 | int ret; | |
4246 | u64 disk_bytenr; | |
4247 | LIST_HEAD(list); | |
4248 | ||
4249 | ordered = btrfs_lookup_ordered_extent(inode, file_pos); | |
4250 | BUG_ON(ordered->file_offset != file_pos || ordered->len != len); | |
4251 | ||
4252 | disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; | |
4253 | ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr, | |
a2de733c | 4254 | disk_bytenr + len - 1, &list, 0); |
5d4f98a2 YZ |
4255 | |
4256 | while (!list_empty(&list)) { | |
4257 | sums = list_entry(list.next, struct btrfs_ordered_sum, list); | |
4258 | list_del_init(&sums->list); | |
4259 | ||
4260 | sector_sum = sums->sums; | |
4261 | sums->bytenr = ordered->start; | |
4262 | ||
4263 | offset = 0; | |
4264 | while (offset < sums->len) { | |
4265 | sector_sum->bytenr += ordered->start - disk_bytenr; | |
4266 | sector_sum++; | |
4267 | offset += root->sectorsize; | |
4268 | } | |
4269 | ||
4270 | btrfs_add_ordered_sum(inode, ordered, sums); | |
4271 | } | |
4272 | btrfs_put_ordered_extent(ordered); | |
411fc6bc | 4273 | return ret; |
5d4f98a2 | 4274 | } |
3fd0a558 YZ |
4275 | |
4276 | void btrfs_reloc_cow_block(struct btrfs_trans_handle *trans, | |
4277 | struct btrfs_root *root, struct extent_buffer *buf, | |
4278 | struct extent_buffer *cow) | |
4279 | { | |
4280 | struct reloc_control *rc; | |
4281 | struct backref_node *node; | |
4282 | int first_cow = 0; | |
4283 | int level; | |
4284 | int ret; | |
4285 | ||
4286 | rc = root->fs_info->reloc_ctl; | |
4287 | if (!rc) | |
4288 | return; | |
4289 | ||
4290 | BUG_ON(rc->stage == UPDATE_DATA_PTRS && | |
4291 | root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID); | |
4292 | ||
4293 | level = btrfs_header_level(buf); | |
4294 | if (btrfs_header_generation(buf) <= | |
4295 | btrfs_root_last_snapshot(&root->root_item)) | |
4296 | first_cow = 1; | |
4297 | ||
4298 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID && | |
4299 | rc->create_reloc_tree) { | |
4300 | WARN_ON(!first_cow && level == 0); | |
4301 | ||
4302 | node = rc->backref_cache.path[level]; | |
4303 | BUG_ON(node->bytenr != buf->start && | |
4304 | node->new_bytenr != buf->start); | |
4305 | ||
4306 | drop_node_buffer(node); | |
4307 | extent_buffer_get(cow); | |
4308 | node->eb = cow; | |
4309 | node->new_bytenr = cow->start; | |
4310 | ||
4311 | if (!node->pending) { | |
4312 | list_move_tail(&node->list, | |
4313 | &rc->backref_cache.pending[level]); | |
4314 | node->pending = 1; | |
4315 | } | |
4316 | ||
4317 | if (first_cow) | |
4318 | __mark_block_processed(rc, node); | |
4319 | ||
4320 | if (first_cow && level > 0) | |
4321 | rc->nodes_relocated += buf->len; | |
4322 | } | |
4323 | ||
4324 | if (level == 0 && first_cow && rc->stage == UPDATE_DATA_PTRS) { | |
4325 | ret = replace_file_extents(trans, rc, root, cow); | |
4326 | BUG_ON(ret); | |
4327 | } | |
4328 | } | |
4329 | ||
4330 | /* | |
4331 | * called before creating snapshot. it calculates metadata reservation | |
4332 | * requried for relocating tree blocks in the snapshot | |
4333 | */ | |
4334 | void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle *trans, | |
4335 | struct btrfs_pending_snapshot *pending, | |
4336 | u64 *bytes_to_reserve) | |
4337 | { | |
4338 | struct btrfs_root *root; | |
4339 | struct reloc_control *rc; | |
4340 | ||
4341 | root = pending->root; | |
4342 | if (!root->reloc_root) | |
4343 | return; | |
4344 | ||
4345 | rc = root->fs_info->reloc_ctl; | |
4346 | if (!rc->merge_reloc_tree) | |
4347 | return; | |
4348 | ||
4349 | root = root->reloc_root; | |
4350 | BUG_ON(btrfs_root_refs(&root->root_item) == 0); | |
4351 | /* | |
4352 | * relocation is in the stage of merging trees. the space | |
4353 | * used by merging a reloc tree is twice the size of | |
4354 | * relocated tree nodes in the worst case. half for cowing | |
4355 | * the reloc tree, half for cowing the fs tree. the space | |
4356 | * used by cowing the reloc tree will be freed after the | |
4357 | * tree is dropped. if we create snapshot, cowing the fs | |
4358 | * tree may use more space than it frees. so we need | |
4359 | * reserve extra space. | |
4360 | */ | |
4361 | *bytes_to_reserve += rc->nodes_relocated; | |
4362 | } | |
4363 | ||
4364 | /* | |
4365 | * called after snapshot is created. migrate block reservation | |
4366 | * and create reloc root for the newly created snapshot | |
4367 | */ | |
4368 | void btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans, | |
4369 | struct btrfs_pending_snapshot *pending) | |
4370 | { | |
4371 | struct btrfs_root *root = pending->root; | |
4372 | struct btrfs_root *reloc_root; | |
4373 | struct btrfs_root *new_root; | |
4374 | struct reloc_control *rc; | |
4375 | int ret; | |
4376 | ||
4377 | if (!root->reloc_root) | |
4378 | return; | |
4379 | ||
4380 | rc = root->fs_info->reloc_ctl; | |
4381 | rc->merging_rsv_size += rc->nodes_relocated; | |
4382 | ||
4383 | if (rc->merge_reloc_tree) { | |
4384 | ret = btrfs_block_rsv_migrate(&pending->block_rsv, | |
4385 | rc->block_rsv, | |
4386 | rc->nodes_relocated); | |
4387 | BUG_ON(ret); | |
4388 | } | |
4389 | ||
4390 | new_root = pending->snap; | |
4391 | reloc_root = create_reloc_root(trans, root->reloc_root, | |
4392 | new_root->root_key.objectid); | |
4393 | ||
4394 | __add_reloc_root(reloc_root); | |
4395 | new_root->reloc_root = reloc_root; | |
4396 | ||
4397 | if (rc->create_reloc_tree) { | |
4398 | ret = clone_backref_node(trans, rc, root, reloc_root); | |
4399 | BUG_ON(ret); | |
4400 | } | |
4401 | } |