Commit | Line | Data |
---|---|---|
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> | |
24 | #include "ctree.h" | |
25 | #include "disk-io.h" | |
26 | #include "transaction.h" | |
27 | #include "volumes.h" | |
28 | #include "locking.h" | |
29 | #include "btrfs_inode.h" | |
30 | #include "async-thread.h" | |
31 | ||
32 | /* | |
33 | * backref_node, mapping_node and tree_block start with this | |
34 | */ | |
35 | struct tree_entry { | |
36 | struct rb_node rb_node; | |
37 | u64 bytenr; | |
38 | }; | |
39 | ||
40 | /* | |
41 | * present a tree block in the backref cache | |
42 | */ | |
43 | struct backref_node { | |
44 | struct rb_node rb_node; | |
45 | u64 bytenr; | |
46 | /* objectid tree block owner */ | |
47 | u64 owner; | |
48 | /* list of upper level blocks reference this block */ | |
49 | struct list_head upper; | |
50 | /* list of child blocks in the cache */ | |
51 | struct list_head lower; | |
52 | /* NULL if this node is not tree root */ | |
53 | struct btrfs_root *root; | |
54 | /* extent buffer got by COW the block */ | |
55 | struct extent_buffer *eb; | |
56 | /* level of tree block */ | |
57 | unsigned int level:8; | |
58 | /* 1 if the block is root of old snapshot */ | |
59 | unsigned int old_root:1; | |
60 | /* 1 if no child blocks in the cache */ | |
61 | unsigned int lowest:1; | |
62 | /* is the extent buffer locked */ | |
63 | unsigned int locked:1; | |
64 | /* has the block been processed */ | |
65 | unsigned int processed:1; | |
66 | /* have backrefs of this block been checked */ | |
67 | unsigned int checked:1; | |
68 | }; | |
69 | ||
70 | /* | |
71 | * present a block pointer in the backref cache | |
72 | */ | |
73 | struct backref_edge { | |
74 | struct list_head list[2]; | |
75 | struct backref_node *node[2]; | |
76 | u64 blockptr; | |
77 | }; | |
78 | ||
79 | #define LOWER 0 | |
80 | #define UPPER 1 | |
81 | ||
82 | struct backref_cache { | |
83 | /* red black tree of all backref nodes in the cache */ | |
84 | struct rb_root rb_root; | |
85 | /* list of backref nodes with no child block in the cache */ | |
86 | struct list_head pending[BTRFS_MAX_LEVEL]; | |
87 | spinlock_t lock; | |
88 | }; | |
89 | ||
90 | /* | |
91 | * map address of tree root to tree | |
92 | */ | |
93 | struct mapping_node { | |
94 | struct rb_node rb_node; | |
95 | u64 bytenr; | |
96 | void *data; | |
97 | }; | |
98 | ||
99 | struct mapping_tree { | |
100 | struct rb_root rb_root; | |
101 | spinlock_t lock; | |
102 | }; | |
103 | ||
104 | /* | |
105 | * present a tree block to process | |
106 | */ | |
107 | struct tree_block { | |
108 | struct rb_node rb_node; | |
109 | u64 bytenr; | |
110 | struct btrfs_key key; | |
111 | unsigned int level:8; | |
112 | unsigned int key_ready:1; | |
113 | }; | |
114 | ||
115 | /* inode vector */ | |
116 | #define INODEVEC_SIZE 16 | |
117 | ||
118 | struct inodevec { | |
119 | struct list_head list; | |
120 | struct inode *inode[INODEVEC_SIZE]; | |
121 | int nr; | |
122 | }; | |
123 | ||
124 | struct reloc_control { | |
125 | /* block group to relocate */ | |
126 | struct btrfs_block_group_cache *block_group; | |
127 | /* extent tree */ | |
128 | struct btrfs_root *extent_root; | |
129 | /* inode for moving data */ | |
130 | struct inode *data_inode; | |
131 | struct btrfs_workers workers; | |
132 | /* tree blocks have been processed */ | |
133 | struct extent_io_tree processed_blocks; | |
134 | /* map start of tree root to corresponding reloc tree */ | |
135 | struct mapping_tree reloc_root_tree; | |
136 | /* list of reloc trees */ | |
137 | struct list_head reloc_roots; | |
138 | u64 search_start; | |
139 | u64 extents_found; | |
140 | u64 extents_skipped; | |
141 | int stage; | |
142 | int create_reloc_root; | |
143 | unsigned int found_file_extent:1; | |
144 | unsigned int found_old_snapshot:1; | |
145 | }; | |
146 | ||
147 | /* stages of data relocation */ | |
148 | #define MOVE_DATA_EXTENTS 0 | |
149 | #define UPDATE_DATA_PTRS 1 | |
150 | ||
151 | /* | |
152 | * merge reloc tree to corresponding fs tree in worker threads | |
153 | */ | |
154 | struct async_merge { | |
155 | struct btrfs_work work; | |
156 | struct reloc_control *rc; | |
157 | struct btrfs_root *root; | |
158 | struct completion *done; | |
159 | atomic_t *num_pending; | |
160 | }; | |
161 | ||
162 | static void mapping_tree_init(struct mapping_tree *tree) | |
163 | { | |
164 | tree->rb_root.rb_node = NULL; | |
165 | spin_lock_init(&tree->lock); | |
166 | } | |
167 | ||
168 | static void backref_cache_init(struct backref_cache *cache) | |
169 | { | |
170 | int i; | |
171 | cache->rb_root.rb_node = NULL; | |
172 | for (i = 0; i < BTRFS_MAX_LEVEL; i++) | |
173 | INIT_LIST_HEAD(&cache->pending[i]); | |
174 | spin_lock_init(&cache->lock); | |
175 | } | |
176 | ||
177 | static void backref_node_init(struct backref_node *node) | |
178 | { | |
179 | memset(node, 0, sizeof(*node)); | |
180 | INIT_LIST_HEAD(&node->upper); | |
181 | INIT_LIST_HEAD(&node->lower); | |
182 | RB_CLEAR_NODE(&node->rb_node); | |
183 | } | |
184 | ||
185 | static struct rb_node *tree_insert(struct rb_root *root, u64 bytenr, | |
186 | struct rb_node *node) | |
187 | { | |
188 | struct rb_node **p = &root->rb_node; | |
189 | struct rb_node *parent = NULL; | |
190 | struct tree_entry *entry; | |
191 | ||
192 | while (*p) { | |
193 | parent = *p; | |
194 | entry = rb_entry(parent, struct tree_entry, rb_node); | |
195 | ||
196 | if (bytenr < entry->bytenr) | |
197 | p = &(*p)->rb_left; | |
198 | else if (bytenr > entry->bytenr) | |
199 | p = &(*p)->rb_right; | |
200 | else | |
201 | return parent; | |
202 | } | |
203 | ||
204 | rb_link_node(node, parent, p); | |
205 | rb_insert_color(node, root); | |
206 | return NULL; | |
207 | } | |
208 | ||
209 | static struct rb_node *tree_search(struct rb_root *root, u64 bytenr) | |
210 | { | |
211 | struct rb_node *n = root->rb_node; | |
212 | struct tree_entry *entry; | |
213 | ||
214 | while (n) { | |
215 | entry = rb_entry(n, struct tree_entry, rb_node); | |
216 | ||
217 | if (bytenr < entry->bytenr) | |
218 | n = n->rb_left; | |
219 | else if (bytenr > entry->bytenr) | |
220 | n = n->rb_right; | |
221 | else | |
222 | return n; | |
223 | } | |
224 | return NULL; | |
225 | } | |
226 | ||
227 | /* | |
228 | * walk up backref nodes until reach node presents tree root | |
229 | */ | |
230 | static struct backref_node *walk_up_backref(struct backref_node *node, | |
231 | struct backref_edge *edges[], | |
232 | int *index) | |
233 | { | |
234 | struct backref_edge *edge; | |
235 | int idx = *index; | |
236 | ||
237 | while (!list_empty(&node->upper)) { | |
238 | edge = list_entry(node->upper.next, | |
239 | struct backref_edge, list[LOWER]); | |
240 | edges[idx++] = edge; | |
241 | node = edge->node[UPPER]; | |
242 | } | |
243 | *index = idx; | |
244 | return node; | |
245 | } | |
246 | ||
247 | /* | |
248 | * walk down backref nodes to find start of next reference path | |
249 | */ | |
250 | static struct backref_node *walk_down_backref(struct backref_edge *edges[], | |
251 | int *index) | |
252 | { | |
253 | struct backref_edge *edge; | |
254 | struct backref_node *lower; | |
255 | int idx = *index; | |
256 | ||
257 | while (idx > 0) { | |
258 | edge = edges[idx - 1]; | |
259 | lower = edge->node[LOWER]; | |
260 | if (list_is_last(&edge->list[LOWER], &lower->upper)) { | |
261 | idx--; | |
262 | continue; | |
263 | } | |
264 | edge = list_entry(edge->list[LOWER].next, | |
265 | struct backref_edge, list[LOWER]); | |
266 | edges[idx - 1] = edge; | |
267 | *index = idx; | |
268 | return edge->node[UPPER]; | |
269 | } | |
270 | *index = 0; | |
271 | return NULL; | |
272 | } | |
273 | ||
274 | static void drop_node_buffer(struct backref_node *node) | |
275 | { | |
276 | if (node->eb) { | |
277 | if (node->locked) { | |
278 | btrfs_tree_unlock(node->eb); | |
279 | node->locked = 0; | |
280 | } | |
281 | free_extent_buffer(node->eb); | |
282 | node->eb = NULL; | |
283 | } | |
284 | } | |
285 | ||
286 | static void drop_backref_node(struct backref_cache *tree, | |
287 | struct backref_node *node) | |
288 | { | |
289 | BUG_ON(!node->lowest); | |
290 | BUG_ON(!list_empty(&node->upper)); | |
291 | ||
292 | drop_node_buffer(node); | |
293 | list_del(&node->lower); | |
294 | ||
295 | rb_erase(&node->rb_node, &tree->rb_root); | |
296 | kfree(node); | |
297 | } | |
298 | ||
299 | /* | |
300 | * remove a backref node from the backref cache | |
301 | */ | |
302 | static void remove_backref_node(struct backref_cache *cache, | |
303 | struct backref_node *node) | |
304 | { | |
305 | struct backref_node *upper; | |
306 | struct backref_edge *edge; | |
307 | ||
308 | if (!node) | |
309 | return; | |
310 | ||
311 | BUG_ON(!node->lowest); | |
312 | while (!list_empty(&node->upper)) { | |
313 | edge = list_entry(node->upper.next, struct backref_edge, | |
314 | list[LOWER]); | |
315 | upper = edge->node[UPPER]; | |
316 | list_del(&edge->list[LOWER]); | |
317 | list_del(&edge->list[UPPER]); | |
318 | kfree(edge); | |
319 | /* | |
320 | * add the node to pending list if no other | |
321 | * child block cached. | |
322 | */ | |
323 | if (list_empty(&upper->lower)) { | |
324 | list_add_tail(&upper->lower, | |
325 | &cache->pending[upper->level]); | |
326 | upper->lowest = 1; | |
327 | } | |
328 | } | |
329 | drop_backref_node(cache, node); | |
330 | } | |
331 | ||
332 | /* | |
333 | * find reloc tree by address of tree root | |
334 | */ | |
335 | static struct btrfs_root *find_reloc_root(struct reloc_control *rc, | |
336 | u64 bytenr) | |
337 | { | |
338 | struct rb_node *rb_node; | |
339 | struct mapping_node *node; | |
340 | struct btrfs_root *root = NULL; | |
341 | ||
342 | spin_lock(&rc->reloc_root_tree.lock); | |
343 | rb_node = tree_search(&rc->reloc_root_tree.rb_root, bytenr); | |
344 | if (rb_node) { | |
345 | node = rb_entry(rb_node, struct mapping_node, rb_node); | |
346 | root = (struct btrfs_root *)node->data; | |
347 | } | |
348 | spin_unlock(&rc->reloc_root_tree.lock); | |
349 | return root; | |
350 | } | |
351 | ||
352 | static int is_cowonly_root(u64 root_objectid) | |
353 | { | |
354 | if (root_objectid == BTRFS_ROOT_TREE_OBJECTID || | |
355 | root_objectid == BTRFS_EXTENT_TREE_OBJECTID || | |
356 | root_objectid == BTRFS_CHUNK_TREE_OBJECTID || | |
357 | root_objectid == BTRFS_DEV_TREE_OBJECTID || | |
358 | root_objectid == BTRFS_TREE_LOG_OBJECTID || | |
359 | root_objectid == BTRFS_CSUM_TREE_OBJECTID) | |
360 | return 1; | |
361 | return 0; | |
362 | } | |
363 | ||
364 | static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info, | |
365 | u64 root_objectid) | |
366 | { | |
367 | struct btrfs_key key; | |
368 | ||
369 | key.objectid = root_objectid; | |
370 | key.type = BTRFS_ROOT_ITEM_KEY; | |
371 | if (is_cowonly_root(root_objectid)) | |
372 | key.offset = 0; | |
373 | else | |
374 | key.offset = (u64)-1; | |
375 | ||
376 | return btrfs_read_fs_root_no_name(fs_info, &key); | |
377 | } | |
378 | ||
379 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
380 | static noinline_for_stack | |
381 | struct btrfs_root *find_tree_root(struct reloc_control *rc, | |
382 | struct extent_buffer *leaf, | |
383 | struct btrfs_extent_ref_v0 *ref0) | |
384 | { | |
385 | struct btrfs_root *root; | |
386 | u64 root_objectid = btrfs_ref_root_v0(leaf, ref0); | |
387 | u64 generation = btrfs_ref_generation_v0(leaf, ref0); | |
388 | ||
389 | BUG_ON(root_objectid == BTRFS_TREE_RELOC_OBJECTID); | |
390 | ||
391 | root = read_fs_root(rc->extent_root->fs_info, root_objectid); | |
392 | BUG_ON(IS_ERR(root)); | |
393 | ||
394 | if (root->ref_cows && | |
395 | generation != btrfs_root_generation(&root->root_item)) | |
396 | return NULL; | |
397 | ||
398 | return root; | |
399 | } | |
400 | #endif | |
401 | ||
402 | static noinline_for_stack | |
403 | int find_inline_backref(struct extent_buffer *leaf, int slot, | |
404 | unsigned long *ptr, unsigned long *end) | |
405 | { | |
406 | struct btrfs_extent_item *ei; | |
407 | struct btrfs_tree_block_info *bi; | |
408 | u32 item_size; | |
409 | ||
410 | item_size = btrfs_item_size_nr(leaf, slot); | |
411 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
412 | if (item_size < sizeof(*ei)) { | |
413 | WARN_ON(item_size != sizeof(struct btrfs_extent_item_v0)); | |
414 | return 1; | |
415 | } | |
416 | #endif | |
417 | ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item); | |
418 | WARN_ON(!(btrfs_extent_flags(leaf, ei) & | |
419 | BTRFS_EXTENT_FLAG_TREE_BLOCK)); | |
420 | ||
421 | if (item_size <= sizeof(*ei) + sizeof(*bi)) { | |
422 | WARN_ON(item_size < sizeof(*ei) + sizeof(*bi)); | |
423 | return 1; | |
424 | } | |
425 | ||
426 | bi = (struct btrfs_tree_block_info *)(ei + 1); | |
427 | *ptr = (unsigned long)(bi + 1); | |
428 | *end = (unsigned long)ei + item_size; | |
429 | return 0; | |
430 | } | |
431 | ||
432 | /* | |
433 | * build backref tree for a given tree block. root of the backref tree | |
434 | * corresponds the tree block, leaves of the backref tree correspond | |
435 | * roots of b-trees that reference the tree block. | |
436 | * | |
437 | * the basic idea of this function is check backrefs of a given block | |
438 | * to find upper level blocks that refernece the block, and then check | |
439 | * bakcrefs of these upper level blocks recursively. the recursion stop | |
440 | * when tree root is reached or backrefs for the block is cached. | |
441 | * | |
442 | * NOTE: if we find backrefs for a block are cached, we know backrefs | |
443 | * for all upper level blocks that directly/indirectly reference the | |
444 | * block are also cached. | |
445 | */ | |
446 | static struct backref_node *build_backref_tree(struct reloc_control *rc, | |
447 | struct backref_cache *cache, | |
448 | struct btrfs_key *node_key, | |
449 | int level, u64 bytenr) | |
450 | { | |
451 | struct btrfs_path *path1; | |
452 | struct btrfs_path *path2; | |
453 | struct extent_buffer *eb; | |
454 | struct btrfs_root *root; | |
455 | struct backref_node *cur; | |
456 | struct backref_node *upper; | |
457 | struct backref_node *lower; | |
458 | struct backref_node *node = NULL; | |
459 | struct backref_node *exist = NULL; | |
460 | struct backref_edge *edge; | |
461 | struct rb_node *rb_node; | |
462 | struct btrfs_key key; | |
463 | unsigned long end; | |
464 | unsigned long ptr; | |
465 | LIST_HEAD(list); | |
466 | int ret; | |
467 | int err = 0; | |
468 | ||
469 | path1 = btrfs_alloc_path(); | |
470 | path2 = btrfs_alloc_path(); | |
471 | if (!path1 || !path2) { | |
472 | err = -ENOMEM; | |
473 | goto out; | |
474 | } | |
475 | ||
476 | node = kmalloc(sizeof(*node), GFP_NOFS); | |
477 | if (!node) { | |
478 | err = -ENOMEM; | |
479 | goto out; | |
480 | } | |
481 | ||
482 | backref_node_init(node); | |
483 | node->bytenr = bytenr; | |
484 | node->owner = 0; | |
485 | node->level = level; | |
486 | node->lowest = 1; | |
487 | cur = node; | |
488 | again: | |
489 | end = 0; | |
490 | ptr = 0; | |
491 | key.objectid = cur->bytenr; | |
492 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
493 | key.offset = (u64)-1; | |
494 | ||
495 | path1->search_commit_root = 1; | |
496 | path1->skip_locking = 1; | |
497 | ret = btrfs_search_slot(NULL, rc->extent_root, &key, path1, | |
498 | 0, 0); | |
499 | if (ret < 0) { | |
500 | err = ret; | |
501 | goto out; | |
502 | } | |
503 | BUG_ON(!ret || !path1->slots[0]); | |
504 | ||
505 | path1->slots[0]--; | |
506 | ||
507 | WARN_ON(cur->checked); | |
508 | if (!list_empty(&cur->upper)) { | |
509 | /* | |
510 | * the backref was added previously when processsing | |
511 | * backref of type BTRFS_TREE_BLOCK_REF_KEY | |
512 | */ | |
513 | BUG_ON(!list_is_singular(&cur->upper)); | |
514 | edge = list_entry(cur->upper.next, struct backref_edge, | |
515 | list[LOWER]); | |
516 | BUG_ON(!list_empty(&edge->list[UPPER])); | |
517 | exist = edge->node[UPPER]; | |
518 | /* | |
519 | * add the upper level block to pending list if we need | |
520 | * check its backrefs | |
521 | */ | |
522 | if (!exist->checked) | |
523 | list_add_tail(&edge->list[UPPER], &list); | |
524 | } else { | |
525 | exist = NULL; | |
526 | } | |
527 | ||
528 | while (1) { | |
529 | cond_resched(); | |
530 | eb = path1->nodes[0]; | |
531 | ||
532 | if (ptr >= end) { | |
533 | if (path1->slots[0] >= btrfs_header_nritems(eb)) { | |
534 | ret = btrfs_next_leaf(rc->extent_root, path1); | |
535 | if (ret < 0) { | |
536 | err = ret; | |
537 | goto out; | |
538 | } | |
539 | if (ret > 0) | |
540 | break; | |
541 | eb = path1->nodes[0]; | |
542 | } | |
543 | ||
544 | btrfs_item_key_to_cpu(eb, &key, path1->slots[0]); | |
545 | if (key.objectid != cur->bytenr) { | |
546 | WARN_ON(exist); | |
547 | break; | |
548 | } | |
549 | ||
550 | if (key.type == BTRFS_EXTENT_ITEM_KEY) { | |
551 | ret = find_inline_backref(eb, path1->slots[0], | |
552 | &ptr, &end); | |
553 | if (ret) | |
554 | goto next; | |
555 | } | |
556 | } | |
557 | ||
558 | if (ptr < end) { | |
559 | /* update key for inline back ref */ | |
560 | struct btrfs_extent_inline_ref *iref; | |
561 | iref = (struct btrfs_extent_inline_ref *)ptr; | |
562 | key.type = btrfs_extent_inline_ref_type(eb, iref); | |
563 | key.offset = btrfs_extent_inline_ref_offset(eb, iref); | |
564 | WARN_ON(key.type != BTRFS_TREE_BLOCK_REF_KEY && | |
565 | key.type != BTRFS_SHARED_BLOCK_REF_KEY); | |
566 | } | |
567 | ||
568 | if (exist && | |
569 | ((key.type == BTRFS_TREE_BLOCK_REF_KEY && | |
570 | exist->owner == key.offset) || | |
571 | (key.type == BTRFS_SHARED_BLOCK_REF_KEY && | |
572 | exist->bytenr == key.offset))) { | |
573 | exist = NULL; | |
574 | goto next; | |
575 | } | |
576 | ||
577 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
578 | if (key.type == BTRFS_SHARED_BLOCK_REF_KEY || | |
579 | key.type == BTRFS_EXTENT_REF_V0_KEY) { | |
580 | if (key.objectid == key.offset && | |
581 | key.type == BTRFS_EXTENT_REF_V0_KEY) { | |
582 | struct btrfs_extent_ref_v0 *ref0; | |
583 | ref0 = btrfs_item_ptr(eb, path1->slots[0], | |
584 | struct btrfs_extent_ref_v0); | |
585 | root = find_tree_root(rc, eb, ref0); | |
586 | if (root) | |
587 | cur->root = root; | |
588 | else | |
589 | cur->old_root = 1; | |
590 | break; | |
591 | } | |
592 | #else | |
593 | BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY); | |
594 | if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) { | |
595 | #endif | |
596 | if (key.objectid == key.offset) { | |
597 | /* | |
598 | * only root blocks of reloc trees use | |
599 | * backref of this type. | |
600 | */ | |
601 | root = find_reloc_root(rc, cur->bytenr); | |
602 | BUG_ON(!root); | |
603 | cur->root = root; | |
604 | break; | |
605 | } | |
606 | ||
607 | edge = kzalloc(sizeof(*edge), GFP_NOFS); | |
608 | if (!edge) { | |
609 | err = -ENOMEM; | |
610 | goto out; | |
611 | } | |
612 | rb_node = tree_search(&cache->rb_root, key.offset); | |
613 | if (!rb_node) { | |
614 | upper = kmalloc(sizeof(*upper), GFP_NOFS); | |
615 | if (!upper) { | |
616 | kfree(edge); | |
617 | err = -ENOMEM; | |
618 | goto out; | |
619 | } | |
620 | backref_node_init(upper); | |
621 | upper->bytenr = key.offset; | |
622 | upper->owner = 0; | |
623 | upper->level = cur->level + 1; | |
624 | /* | |
625 | * backrefs for the upper level block isn't | |
626 | * cached, add the block to pending list | |
627 | */ | |
628 | list_add_tail(&edge->list[UPPER], &list); | |
629 | } else { | |
630 | upper = rb_entry(rb_node, struct backref_node, | |
631 | rb_node); | |
632 | INIT_LIST_HEAD(&edge->list[UPPER]); | |
633 | } | |
634 | list_add(&edge->list[LOWER], &cur->upper); | |
635 | edge->node[UPPER] = upper; | |
636 | edge->node[LOWER] = cur; | |
637 | ||
638 | goto next; | |
639 | } else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) { | |
640 | goto next; | |
641 | } | |
642 | ||
643 | /* key.type == BTRFS_TREE_BLOCK_REF_KEY */ | |
644 | root = read_fs_root(rc->extent_root->fs_info, key.offset); | |
645 | if (IS_ERR(root)) { | |
646 | err = PTR_ERR(root); | |
647 | goto out; | |
648 | } | |
649 | ||
650 | if (btrfs_root_level(&root->root_item) == cur->level) { | |
651 | /* tree root */ | |
652 | BUG_ON(btrfs_root_bytenr(&root->root_item) != | |
653 | cur->bytenr); | |
654 | cur->root = root; | |
655 | break; | |
656 | } | |
657 | ||
658 | level = cur->level + 1; | |
659 | ||
660 | /* | |
661 | * searching the tree to find upper level blocks | |
662 | * reference the block. | |
663 | */ | |
664 | path2->search_commit_root = 1; | |
665 | path2->skip_locking = 1; | |
666 | path2->lowest_level = level; | |
667 | ret = btrfs_search_slot(NULL, root, node_key, path2, 0, 0); | |
668 | path2->lowest_level = 0; | |
669 | if (ret < 0) { | |
670 | err = ret; | |
671 | goto out; | |
672 | } | |
673 | ||
674 | eb = path2->nodes[level]; | |
675 | WARN_ON(btrfs_node_blockptr(eb, path2->slots[level]) != | |
676 | cur->bytenr); | |
677 | ||
678 | lower = cur; | |
679 | for (; level < BTRFS_MAX_LEVEL; level++) { | |
680 | if (!path2->nodes[level]) { | |
681 | BUG_ON(btrfs_root_bytenr(&root->root_item) != | |
682 | lower->bytenr); | |
683 | lower->root = root; | |
684 | break; | |
685 | } | |
686 | ||
687 | edge = kzalloc(sizeof(*edge), GFP_NOFS); | |
688 | if (!edge) { | |
689 | err = -ENOMEM; | |
690 | goto out; | |
691 | } | |
692 | ||
693 | eb = path2->nodes[level]; | |
694 | rb_node = tree_search(&cache->rb_root, eb->start); | |
695 | if (!rb_node) { | |
696 | upper = kmalloc(sizeof(*upper), GFP_NOFS); | |
697 | if (!upper) { | |
698 | kfree(edge); | |
699 | err = -ENOMEM; | |
700 | goto out; | |
701 | } | |
702 | backref_node_init(upper); | |
703 | upper->bytenr = eb->start; | |
704 | upper->owner = btrfs_header_owner(eb); | |
705 | upper->level = lower->level + 1; | |
706 | ||
707 | /* | |
708 | * if we know the block isn't shared | |
709 | * we can void checking its backrefs. | |
710 | */ | |
711 | if (btrfs_block_can_be_shared(root, eb)) | |
712 | upper->checked = 0; | |
713 | else | |
714 | upper->checked = 1; | |
715 | ||
716 | /* | |
717 | * add the block to pending list if we | |
718 | * need check its backrefs. only block | |
719 | * at 'cur->level + 1' is added to the | |
720 | * tail of pending list. this guarantees | |
721 | * we check backrefs from lower level | |
722 | * blocks to upper level blocks. | |
723 | */ | |
724 | if (!upper->checked && | |
725 | level == cur->level + 1) { | |
726 | list_add_tail(&edge->list[UPPER], | |
727 | &list); | |
728 | } else | |
729 | INIT_LIST_HEAD(&edge->list[UPPER]); | |
730 | } else { | |
731 | upper = rb_entry(rb_node, struct backref_node, | |
732 | rb_node); | |
733 | BUG_ON(!upper->checked); | |
734 | INIT_LIST_HEAD(&edge->list[UPPER]); | |
735 | } | |
736 | list_add_tail(&edge->list[LOWER], &lower->upper); | |
737 | edge->node[UPPER] = upper; | |
738 | edge->node[LOWER] = lower; | |
739 | ||
740 | if (rb_node) | |
741 | break; | |
742 | lower = upper; | |
743 | upper = NULL; | |
744 | } | |
745 | btrfs_release_path(root, path2); | |
746 | next: | |
747 | if (ptr < end) { | |
748 | ptr += btrfs_extent_inline_ref_size(key.type); | |
749 | if (ptr >= end) { | |
750 | WARN_ON(ptr > end); | |
751 | ptr = 0; | |
752 | end = 0; | |
753 | } | |
754 | } | |
755 | if (ptr >= end) | |
756 | path1->slots[0]++; | |
757 | } | |
758 | btrfs_release_path(rc->extent_root, path1); | |
759 | ||
760 | cur->checked = 1; | |
761 | WARN_ON(exist); | |
762 | ||
763 | /* the pending list isn't empty, take the first block to process */ | |
764 | if (!list_empty(&list)) { | |
765 | edge = list_entry(list.next, struct backref_edge, list[UPPER]); | |
766 | list_del_init(&edge->list[UPPER]); | |
767 | cur = edge->node[UPPER]; | |
768 | goto again; | |
769 | } | |
770 | ||
771 | /* | |
772 | * everything goes well, connect backref nodes and insert backref nodes | |
773 | * into the cache. | |
774 | */ | |
775 | BUG_ON(!node->checked); | |
776 | rb_node = tree_insert(&cache->rb_root, node->bytenr, &node->rb_node); | |
777 | BUG_ON(rb_node); | |
778 | ||
779 | list_for_each_entry(edge, &node->upper, list[LOWER]) | |
780 | list_add_tail(&edge->list[UPPER], &list); | |
781 | ||
782 | while (!list_empty(&list)) { | |
783 | edge = list_entry(list.next, struct backref_edge, list[UPPER]); | |
784 | list_del_init(&edge->list[UPPER]); | |
785 | upper = edge->node[UPPER]; | |
786 | ||
787 | if (!RB_EMPTY_NODE(&upper->rb_node)) { | |
788 | if (upper->lowest) { | |
789 | list_del_init(&upper->lower); | |
790 | upper->lowest = 0; | |
791 | } | |
792 | ||
793 | list_add_tail(&edge->list[UPPER], &upper->lower); | |
794 | continue; | |
795 | } | |
796 | ||
797 | BUG_ON(!upper->checked); | |
798 | rb_node = tree_insert(&cache->rb_root, upper->bytenr, | |
799 | &upper->rb_node); | |
800 | BUG_ON(rb_node); | |
801 | ||
802 | list_add_tail(&edge->list[UPPER], &upper->lower); | |
803 | ||
804 | list_for_each_entry(edge, &upper->upper, list[LOWER]) | |
805 | list_add_tail(&edge->list[UPPER], &list); | |
806 | } | |
807 | out: | |
808 | btrfs_free_path(path1); | |
809 | btrfs_free_path(path2); | |
810 | if (err) { | |
811 | INIT_LIST_HEAD(&list); | |
812 | upper = node; | |
813 | while (upper) { | |
814 | if (RB_EMPTY_NODE(&upper->rb_node)) { | |
815 | list_splice_tail(&upper->upper, &list); | |
816 | kfree(upper); | |
817 | } | |
818 | ||
819 | if (list_empty(&list)) | |
820 | break; | |
821 | ||
822 | edge = list_entry(list.next, struct backref_edge, | |
823 | list[LOWER]); | |
824 | upper = edge->node[UPPER]; | |
825 | kfree(edge); | |
826 | } | |
827 | return ERR_PTR(err); | |
828 | } | |
829 | return node; | |
830 | } | |
831 | ||
832 | /* | |
833 | * helper to add 'address of tree root -> reloc tree' mapping | |
834 | */ | |
835 | static int __add_reloc_root(struct btrfs_root *root) | |
836 | { | |
837 | struct rb_node *rb_node; | |
838 | struct mapping_node *node; | |
839 | struct reloc_control *rc = root->fs_info->reloc_ctl; | |
840 | ||
841 | node = kmalloc(sizeof(*node), GFP_NOFS); | |
842 | BUG_ON(!node); | |
843 | ||
844 | node->bytenr = root->node->start; | |
845 | node->data = root; | |
846 | ||
847 | spin_lock(&rc->reloc_root_tree.lock); | |
848 | rb_node = tree_insert(&rc->reloc_root_tree.rb_root, | |
849 | node->bytenr, &node->rb_node); | |
850 | spin_unlock(&rc->reloc_root_tree.lock); | |
851 | BUG_ON(rb_node); | |
852 | ||
853 | list_add_tail(&root->root_list, &rc->reloc_roots); | |
854 | return 0; | |
855 | } | |
856 | ||
857 | /* | |
858 | * helper to update/delete the 'address of tree root -> reloc tree' | |
859 | * mapping | |
860 | */ | |
861 | static int __update_reloc_root(struct btrfs_root *root, int del) | |
862 | { | |
863 | struct rb_node *rb_node; | |
864 | struct mapping_node *node = NULL; | |
865 | struct reloc_control *rc = root->fs_info->reloc_ctl; | |
866 | ||
867 | spin_lock(&rc->reloc_root_tree.lock); | |
868 | rb_node = tree_search(&rc->reloc_root_tree.rb_root, | |
869 | root->commit_root->start); | |
870 | if (rb_node) { | |
871 | node = rb_entry(rb_node, struct mapping_node, rb_node); | |
872 | rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root); | |
873 | } | |
874 | spin_unlock(&rc->reloc_root_tree.lock); | |
875 | ||
876 | BUG_ON((struct btrfs_root *)node->data != root); | |
877 | ||
878 | if (!del) { | |
879 | spin_lock(&rc->reloc_root_tree.lock); | |
880 | node->bytenr = root->node->start; | |
881 | rb_node = tree_insert(&rc->reloc_root_tree.rb_root, | |
882 | node->bytenr, &node->rb_node); | |
883 | spin_unlock(&rc->reloc_root_tree.lock); | |
884 | BUG_ON(rb_node); | |
885 | } else { | |
886 | list_del_init(&root->root_list); | |
887 | kfree(node); | |
888 | } | |
889 | return 0; | |
890 | } | |
891 | ||
892 | /* | |
893 | * create reloc tree for a given fs tree. reloc tree is just a | |
894 | * snapshot of the fs tree with special root objectid. | |
895 | */ | |
896 | int btrfs_init_reloc_root(struct btrfs_trans_handle *trans, | |
897 | struct btrfs_root *root) | |
898 | { | |
899 | struct btrfs_root *reloc_root; | |
900 | struct extent_buffer *eb; | |
901 | struct btrfs_root_item *root_item; | |
902 | struct btrfs_key root_key; | |
903 | int ret; | |
904 | ||
905 | if (root->reloc_root) { | |
906 | reloc_root = root->reloc_root; | |
907 | reloc_root->last_trans = trans->transid; | |
908 | return 0; | |
909 | } | |
910 | ||
911 | if (!root->fs_info->reloc_ctl || | |
912 | !root->fs_info->reloc_ctl->create_reloc_root || | |
913 | root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) | |
914 | return 0; | |
915 | ||
916 | root_item = kmalloc(sizeof(*root_item), GFP_NOFS); | |
917 | BUG_ON(!root_item); | |
918 | ||
919 | root_key.objectid = BTRFS_TREE_RELOC_OBJECTID; | |
920 | root_key.type = BTRFS_ROOT_ITEM_KEY; | |
921 | root_key.offset = root->root_key.objectid; | |
922 | ||
923 | ret = btrfs_copy_root(trans, root, root->commit_root, &eb, | |
924 | BTRFS_TREE_RELOC_OBJECTID); | |
925 | BUG_ON(ret); | |
926 | ||
927 | btrfs_set_root_last_snapshot(&root->root_item, trans->transid - 1); | |
928 | memcpy(root_item, &root->root_item, sizeof(*root_item)); | |
929 | btrfs_set_root_refs(root_item, 1); | |
930 | btrfs_set_root_bytenr(root_item, eb->start); | |
931 | btrfs_set_root_level(root_item, btrfs_header_level(eb)); | |
932 | btrfs_set_root_generation(root_item, trans->transid); | |
933 | memset(&root_item->drop_progress, 0, sizeof(struct btrfs_disk_key)); | |
934 | root_item->drop_level = 0; | |
935 | ||
936 | btrfs_tree_unlock(eb); | |
937 | free_extent_buffer(eb); | |
938 | ||
939 | ret = btrfs_insert_root(trans, root->fs_info->tree_root, | |
940 | &root_key, root_item); | |
941 | BUG_ON(ret); | |
942 | kfree(root_item); | |
943 | ||
944 | reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root, | |
945 | &root_key); | |
946 | BUG_ON(IS_ERR(reloc_root)); | |
947 | reloc_root->last_trans = trans->transid; | |
948 | ||
949 | __add_reloc_root(reloc_root); | |
950 | root->reloc_root = reloc_root; | |
951 | return 0; | |
952 | } | |
953 | ||
954 | /* | |
955 | * update root item of reloc tree | |
956 | */ | |
957 | int btrfs_update_reloc_root(struct btrfs_trans_handle *trans, | |
958 | struct btrfs_root *root) | |
959 | { | |
960 | struct btrfs_root *reloc_root; | |
961 | struct btrfs_root_item *root_item; | |
962 | int del = 0; | |
963 | int ret; | |
964 | ||
965 | if (!root->reloc_root) | |
966 | return 0; | |
967 | ||
968 | reloc_root = root->reloc_root; | |
969 | root_item = &reloc_root->root_item; | |
970 | ||
971 | if (btrfs_root_refs(root_item) == 0) { | |
972 | root->reloc_root = NULL; | |
973 | del = 1; | |
974 | } | |
975 | ||
976 | __update_reloc_root(reloc_root, del); | |
977 | ||
978 | if (reloc_root->commit_root != reloc_root->node) { | |
979 | btrfs_set_root_node(root_item, reloc_root->node); | |
980 | free_extent_buffer(reloc_root->commit_root); | |
981 | reloc_root->commit_root = btrfs_root_node(reloc_root); | |
982 | } | |
983 | ||
984 | ret = btrfs_update_root(trans, root->fs_info->tree_root, | |
985 | &reloc_root->root_key, root_item); | |
986 | BUG_ON(ret); | |
987 | return 0; | |
988 | } | |
989 | ||
990 | /* | |
991 | * helper to find first cached inode with inode number >= objectid | |
992 | * in a subvolume | |
993 | */ | |
994 | static struct inode *find_next_inode(struct btrfs_root *root, u64 objectid) | |
995 | { | |
996 | struct rb_node *node; | |
997 | struct rb_node *prev; | |
998 | struct btrfs_inode *entry; | |
999 | struct inode *inode; | |
1000 | ||
1001 | spin_lock(&root->inode_lock); | |
1002 | again: | |
1003 | node = root->inode_tree.rb_node; | |
1004 | prev = NULL; | |
1005 | while (node) { | |
1006 | prev = node; | |
1007 | entry = rb_entry(node, struct btrfs_inode, rb_node); | |
1008 | ||
1009 | if (objectid < entry->vfs_inode.i_ino) | |
1010 | node = node->rb_left; | |
1011 | else if (objectid > entry->vfs_inode.i_ino) | |
1012 | node = node->rb_right; | |
1013 | else | |
1014 | break; | |
1015 | } | |
1016 | if (!node) { | |
1017 | while (prev) { | |
1018 | entry = rb_entry(prev, struct btrfs_inode, rb_node); | |
1019 | if (objectid <= entry->vfs_inode.i_ino) { | |
1020 | node = prev; | |
1021 | break; | |
1022 | } | |
1023 | prev = rb_next(prev); | |
1024 | } | |
1025 | } | |
1026 | while (node) { | |
1027 | entry = rb_entry(node, struct btrfs_inode, rb_node); | |
1028 | inode = igrab(&entry->vfs_inode); | |
1029 | if (inode) { | |
1030 | spin_unlock(&root->inode_lock); | |
1031 | return inode; | |
1032 | } | |
1033 | ||
1034 | objectid = entry->vfs_inode.i_ino + 1; | |
1035 | if (cond_resched_lock(&root->inode_lock)) | |
1036 | goto again; | |
1037 | ||
1038 | node = rb_next(node); | |
1039 | } | |
1040 | spin_unlock(&root->inode_lock); | |
1041 | return NULL; | |
1042 | } | |
1043 | ||
1044 | static int in_block_group(u64 bytenr, | |
1045 | struct btrfs_block_group_cache *block_group) | |
1046 | { | |
1047 | if (bytenr >= block_group->key.objectid && | |
1048 | bytenr < block_group->key.objectid + block_group->key.offset) | |
1049 | return 1; | |
1050 | return 0; | |
1051 | } | |
1052 | ||
1053 | /* | |
1054 | * get new location of data | |
1055 | */ | |
1056 | static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr, | |
1057 | u64 bytenr, u64 num_bytes) | |
1058 | { | |
1059 | struct btrfs_root *root = BTRFS_I(reloc_inode)->root; | |
1060 | struct btrfs_path *path; | |
1061 | struct btrfs_file_extent_item *fi; | |
1062 | struct extent_buffer *leaf; | |
1063 | int ret; | |
1064 | ||
1065 | path = btrfs_alloc_path(); | |
1066 | if (!path) | |
1067 | return -ENOMEM; | |
1068 | ||
1069 | bytenr -= BTRFS_I(reloc_inode)->index_cnt; | |
1070 | ret = btrfs_lookup_file_extent(NULL, root, path, reloc_inode->i_ino, | |
1071 | bytenr, 0); | |
1072 | if (ret < 0) | |
1073 | goto out; | |
1074 | if (ret > 0) { | |
1075 | ret = -ENOENT; | |
1076 | goto out; | |
1077 | } | |
1078 | ||
1079 | leaf = path->nodes[0]; | |
1080 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
1081 | struct btrfs_file_extent_item); | |
1082 | ||
1083 | BUG_ON(btrfs_file_extent_offset(leaf, fi) || | |
1084 | btrfs_file_extent_compression(leaf, fi) || | |
1085 | btrfs_file_extent_encryption(leaf, fi) || | |
1086 | btrfs_file_extent_other_encoding(leaf, fi)); | |
1087 | ||
1088 | if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) { | |
1089 | ret = 1; | |
1090 | goto out; | |
1091 | } | |
1092 | ||
1093 | if (new_bytenr) | |
1094 | *new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
1095 | ret = 0; | |
1096 | out: | |
1097 | btrfs_free_path(path); | |
1098 | return ret; | |
1099 | } | |
1100 | ||
1101 | /* | |
1102 | * update file extent items in the tree leaf to point to | |
1103 | * the new locations. | |
1104 | */ | |
1105 | static int replace_file_extents(struct btrfs_trans_handle *trans, | |
1106 | struct reloc_control *rc, | |
1107 | struct btrfs_root *root, | |
1108 | struct extent_buffer *leaf, | |
1109 | struct list_head *inode_list) | |
1110 | { | |
1111 | struct btrfs_key key; | |
1112 | struct btrfs_file_extent_item *fi; | |
1113 | struct inode *inode = NULL; | |
1114 | struct inodevec *ivec = NULL; | |
1115 | u64 parent; | |
1116 | u64 bytenr; | |
1117 | u64 new_bytenr; | |
1118 | u64 num_bytes; | |
1119 | u64 end; | |
1120 | u32 nritems; | |
1121 | u32 i; | |
1122 | int ret; | |
1123 | int first = 1; | |
1124 | int dirty = 0; | |
1125 | ||
1126 | if (rc->stage != UPDATE_DATA_PTRS) | |
1127 | return 0; | |
1128 | ||
1129 | /* reloc trees always use full backref */ | |
1130 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) | |
1131 | parent = leaf->start; | |
1132 | else | |
1133 | parent = 0; | |
1134 | ||
1135 | nritems = btrfs_header_nritems(leaf); | |
1136 | for (i = 0; i < nritems; i++) { | |
1137 | cond_resched(); | |
1138 | btrfs_item_key_to_cpu(leaf, &key, i); | |
1139 | if (key.type != BTRFS_EXTENT_DATA_KEY) | |
1140 | continue; | |
1141 | fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); | |
1142 | if (btrfs_file_extent_type(leaf, fi) == | |
1143 | BTRFS_FILE_EXTENT_INLINE) | |
1144 | continue; | |
1145 | bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
1146 | num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); | |
1147 | if (bytenr == 0) | |
1148 | continue; | |
1149 | if (!in_block_group(bytenr, rc->block_group)) | |
1150 | continue; | |
1151 | ||
1152 | /* | |
1153 | * if we are modifying block in fs tree, wait for readpage | |
1154 | * to complete and drop the extent cache | |
1155 | */ | |
1156 | if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) { | |
1157 | if (!ivec || ivec->nr == INODEVEC_SIZE) { | |
1158 | ivec = kmalloc(sizeof(*ivec), GFP_NOFS); | |
1159 | BUG_ON(!ivec); | |
1160 | ivec->nr = 0; | |
1161 | list_add_tail(&ivec->list, inode_list); | |
1162 | } | |
1163 | if (first) { | |
1164 | inode = find_next_inode(root, key.objectid); | |
1165 | if (inode) | |
1166 | ivec->inode[ivec->nr++] = inode; | |
1167 | first = 0; | |
1168 | } else if (inode && inode->i_ino < key.objectid) { | |
1169 | inode = find_next_inode(root, key.objectid); | |
1170 | if (inode) | |
1171 | ivec->inode[ivec->nr++] = inode; | |
1172 | } | |
1173 | if (inode && inode->i_ino == key.objectid) { | |
1174 | end = key.offset + | |
1175 | btrfs_file_extent_num_bytes(leaf, fi); | |
1176 | WARN_ON(!IS_ALIGNED(key.offset, | |
1177 | root->sectorsize)); | |
1178 | WARN_ON(!IS_ALIGNED(end, root->sectorsize)); | |
1179 | end--; | |
1180 | ret = try_lock_extent(&BTRFS_I(inode)->io_tree, | |
1181 | key.offset, end, | |
1182 | GFP_NOFS); | |
1183 | if (!ret) | |
1184 | continue; | |
1185 | ||
1186 | btrfs_drop_extent_cache(inode, key.offset, end, | |
1187 | 1); | |
1188 | unlock_extent(&BTRFS_I(inode)->io_tree, | |
1189 | key.offset, end, GFP_NOFS); | |
1190 | } | |
1191 | } | |
1192 | ||
1193 | ret = get_new_location(rc->data_inode, &new_bytenr, | |
1194 | bytenr, num_bytes); | |
1195 | if (ret > 0) | |
1196 | continue; | |
1197 | BUG_ON(ret < 0); | |
1198 | ||
1199 | btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr); | |
1200 | dirty = 1; | |
1201 | ||
1202 | key.offset -= btrfs_file_extent_offset(leaf, fi); | |
1203 | ret = btrfs_inc_extent_ref(trans, root, new_bytenr, | |
1204 | num_bytes, parent, | |
1205 | btrfs_header_owner(leaf), | |
1206 | key.objectid, key.offset); | |
1207 | BUG_ON(ret); | |
1208 | ||
1209 | ret = btrfs_free_extent(trans, root, bytenr, num_bytes, | |
1210 | parent, btrfs_header_owner(leaf), | |
1211 | key.objectid, key.offset); | |
1212 | BUG_ON(ret); | |
1213 | } | |
1214 | if (dirty) | |
1215 | btrfs_mark_buffer_dirty(leaf); | |
1216 | return 0; | |
1217 | } | |
1218 | ||
1219 | static noinline_for_stack | |
1220 | int memcmp_node_keys(struct extent_buffer *eb, int slot, | |
1221 | struct btrfs_path *path, int level) | |
1222 | { | |
1223 | struct btrfs_disk_key key1; | |
1224 | struct btrfs_disk_key key2; | |
1225 | btrfs_node_key(eb, &key1, slot); | |
1226 | btrfs_node_key(path->nodes[level], &key2, path->slots[level]); | |
1227 | return memcmp(&key1, &key2, sizeof(key1)); | |
1228 | } | |
1229 | ||
1230 | /* | |
1231 | * try to replace tree blocks in fs tree with the new blocks | |
1232 | * in reloc tree. tree blocks haven't been modified since the | |
1233 | * reloc tree was create can be replaced. | |
1234 | * | |
1235 | * if a block was replaced, level of the block + 1 is returned. | |
1236 | * if no block got replaced, 0 is returned. if there are other | |
1237 | * errors, a negative error number is returned. | |
1238 | */ | |
1239 | static int replace_path(struct btrfs_trans_handle *trans, | |
1240 | struct btrfs_root *dest, struct btrfs_root *src, | |
1241 | struct btrfs_path *path, struct btrfs_key *next_key, | |
1242 | struct extent_buffer **leaf, | |
1243 | int lowest_level, int max_level) | |
1244 | { | |
1245 | struct extent_buffer *eb; | |
1246 | struct extent_buffer *parent; | |
1247 | struct btrfs_key key; | |
1248 | u64 old_bytenr; | |
1249 | u64 new_bytenr; | |
1250 | u64 old_ptr_gen; | |
1251 | u64 new_ptr_gen; | |
1252 | u64 last_snapshot; | |
1253 | u32 blocksize; | |
1254 | int level; | |
1255 | int ret; | |
1256 | int slot; | |
1257 | ||
1258 | BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID); | |
1259 | BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID); | |
1260 | BUG_ON(lowest_level > 1 && leaf); | |
1261 | ||
1262 | last_snapshot = btrfs_root_last_snapshot(&src->root_item); | |
1263 | ||
1264 | slot = path->slots[lowest_level]; | |
1265 | btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot); | |
1266 | ||
1267 | eb = btrfs_lock_root_node(dest); | |
1268 | btrfs_set_lock_blocking(eb); | |
1269 | level = btrfs_header_level(eb); | |
1270 | ||
1271 | if (level < lowest_level) { | |
1272 | btrfs_tree_unlock(eb); | |
1273 | free_extent_buffer(eb); | |
1274 | return 0; | |
1275 | } | |
1276 | ||
1277 | ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb); | |
1278 | BUG_ON(ret); | |
1279 | btrfs_set_lock_blocking(eb); | |
1280 | ||
1281 | if (next_key) { | |
1282 | next_key->objectid = (u64)-1; | |
1283 | next_key->type = (u8)-1; | |
1284 | next_key->offset = (u64)-1; | |
1285 | } | |
1286 | ||
1287 | parent = eb; | |
1288 | while (1) { | |
1289 | level = btrfs_header_level(parent); | |
1290 | BUG_ON(level < lowest_level); | |
1291 | ||
1292 | ret = btrfs_bin_search(parent, &key, level, &slot); | |
1293 | if (ret && slot > 0) | |
1294 | slot--; | |
1295 | ||
1296 | if (next_key && slot + 1 < btrfs_header_nritems(parent)) | |
1297 | btrfs_node_key_to_cpu(parent, next_key, slot + 1); | |
1298 | ||
1299 | old_bytenr = btrfs_node_blockptr(parent, slot); | |
1300 | blocksize = btrfs_level_size(dest, level - 1); | |
1301 | old_ptr_gen = btrfs_node_ptr_generation(parent, slot); | |
1302 | ||
1303 | if (level <= max_level) { | |
1304 | eb = path->nodes[level]; | |
1305 | new_bytenr = btrfs_node_blockptr(eb, | |
1306 | path->slots[level]); | |
1307 | new_ptr_gen = btrfs_node_ptr_generation(eb, | |
1308 | path->slots[level]); | |
1309 | } else { | |
1310 | new_bytenr = 0; | |
1311 | new_ptr_gen = 0; | |
1312 | } | |
1313 | ||
1314 | if (new_bytenr > 0 && new_bytenr == old_bytenr) { | |
1315 | WARN_ON(1); | |
1316 | ret = level; | |
1317 | break; | |
1318 | } | |
1319 | ||
1320 | if (new_bytenr == 0 || old_ptr_gen > last_snapshot || | |
1321 | memcmp_node_keys(parent, slot, path, level)) { | |
1322 | if (level <= lowest_level && !leaf) { | |
1323 | ret = 0; | |
1324 | break; | |
1325 | } | |
1326 | ||
1327 | eb = read_tree_block(dest, old_bytenr, blocksize, | |
1328 | old_ptr_gen); | |
1329 | btrfs_tree_lock(eb); | |
1330 | ret = btrfs_cow_block(trans, dest, eb, parent, | |
1331 | slot, &eb); | |
1332 | BUG_ON(ret); | |
1333 | btrfs_set_lock_blocking(eb); | |
1334 | ||
1335 | if (level <= lowest_level) { | |
1336 | *leaf = eb; | |
1337 | ret = 0; | |
1338 | break; | |
1339 | } | |
1340 | ||
1341 | btrfs_tree_unlock(parent); | |
1342 | free_extent_buffer(parent); | |
1343 | ||
1344 | parent = eb; | |
1345 | continue; | |
1346 | } | |
1347 | ||
1348 | btrfs_node_key_to_cpu(path->nodes[level], &key, | |
1349 | path->slots[level]); | |
1350 | btrfs_release_path(src, path); | |
1351 | ||
1352 | path->lowest_level = level; | |
1353 | ret = btrfs_search_slot(trans, src, &key, path, 0, 1); | |
1354 | path->lowest_level = 0; | |
1355 | BUG_ON(ret); | |
1356 | ||
1357 | /* | |
1358 | * swap blocks in fs tree and reloc tree. | |
1359 | */ | |
1360 | btrfs_set_node_blockptr(parent, slot, new_bytenr); | |
1361 | btrfs_set_node_ptr_generation(parent, slot, new_ptr_gen); | |
1362 | btrfs_mark_buffer_dirty(parent); | |
1363 | ||
1364 | btrfs_set_node_blockptr(path->nodes[level], | |
1365 | path->slots[level], old_bytenr); | |
1366 | btrfs_set_node_ptr_generation(path->nodes[level], | |
1367 | path->slots[level], old_ptr_gen); | |
1368 | btrfs_mark_buffer_dirty(path->nodes[level]); | |
1369 | ||
1370 | ret = btrfs_inc_extent_ref(trans, src, old_bytenr, blocksize, | |
1371 | path->nodes[level]->start, | |
1372 | src->root_key.objectid, level - 1, 0); | |
1373 | BUG_ON(ret); | |
1374 | ret = btrfs_inc_extent_ref(trans, dest, new_bytenr, blocksize, | |
1375 | 0, dest->root_key.objectid, level - 1, | |
1376 | 0); | |
1377 | BUG_ON(ret); | |
1378 | ||
1379 | ret = btrfs_free_extent(trans, src, new_bytenr, blocksize, | |
1380 | path->nodes[level]->start, | |
1381 | src->root_key.objectid, level - 1, 0); | |
1382 | BUG_ON(ret); | |
1383 | ||
1384 | ret = btrfs_free_extent(trans, dest, old_bytenr, blocksize, | |
1385 | 0, dest->root_key.objectid, level - 1, | |
1386 | 0); | |
1387 | BUG_ON(ret); | |
1388 | ||
1389 | btrfs_unlock_up_safe(path, 0); | |
1390 | ||
1391 | ret = level; | |
1392 | break; | |
1393 | } | |
1394 | btrfs_tree_unlock(parent); | |
1395 | free_extent_buffer(parent); | |
1396 | return ret; | |
1397 | } | |
1398 | ||
1399 | /* | |
1400 | * helper to find next relocated block in reloc tree | |
1401 | */ | |
1402 | static noinline_for_stack | |
1403 | int walk_up_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, | |
1404 | int *level) | |
1405 | { | |
1406 | struct extent_buffer *eb; | |
1407 | int i; | |
1408 | u64 last_snapshot; | |
1409 | u32 nritems; | |
1410 | ||
1411 | last_snapshot = btrfs_root_last_snapshot(&root->root_item); | |
1412 | ||
1413 | for (i = 0; i < *level; i++) { | |
1414 | free_extent_buffer(path->nodes[i]); | |
1415 | path->nodes[i] = NULL; | |
1416 | } | |
1417 | ||
1418 | for (i = *level; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) { | |
1419 | eb = path->nodes[i]; | |
1420 | nritems = btrfs_header_nritems(eb); | |
1421 | while (path->slots[i] + 1 < nritems) { | |
1422 | path->slots[i]++; | |
1423 | if (btrfs_node_ptr_generation(eb, path->slots[i]) <= | |
1424 | last_snapshot) | |
1425 | continue; | |
1426 | ||
1427 | *level = i; | |
1428 | return 0; | |
1429 | } | |
1430 | free_extent_buffer(path->nodes[i]); | |
1431 | path->nodes[i] = NULL; | |
1432 | } | |
1433 | return 1; | |
1434 | } | |
1435 | ||
1436 | /* | |
1437 | * walk down reloc tree to find relocated block of lowest level | |
1438 | */ | |
1439 | static noinline_for_stack | |
1440 | int walk_down_reloc_tree(struct btrfs_root *root, struct btrfs_path *path, | |
1441 | int *level) | |
1442 | { | |
1443 | struct extent_buffer *eb = NULL; | |
1444 | int i; | |
1445 | u64 bytenr; | |
1446 | u64 ptr_gen = 0; | |
1447 | u64 last_snapshot; | |
1448 | u32 blocksize; | |
1449 | u32 nritems; | |
1450 | ||
1451 | last_snapshot = btrfs_root_last_snapshot(&root->root_item); | |
1452 | ||
1453 | for (i = *level; i > 0; i--) { | |
1454 | eb = path->nodes[i]; | |
1455 | nritems = btrfs_header_nritems(eb); | |
1456 | while (path->slots[i] < nritems) { | |
1457 | ptr_gen = btrfs_node_ptr_generation(eb, path->slots[i]); | |
1458 | if (ptr_gen > last_snapshot) | |
1459 | break; | |
1460 | path->slots[i]++; | |
1461 | } | |
1462 | if (path->slots[i] >= nritems) { | |
1463 | if (i == *level) | |
1464 | break; | |
1465 | *level = i + 1; | |
1466 | return 0; | |
1467 | } | |
1468 | if (i == 1) { | |
1469 | *level = i; | |
1470 | return 0; | |
1471 | } | |
1472 | ||
1473 | bytenr = btrfs_node_blockptr(eb, path->slots[i]); | |
1474 | blocksize = btrfs_level_size(root, i - 1); | |
1475 | eb = read_tree_block(root, bytenr, blocksize, ptr_gen); | |
1476 | BUG_ON(btrfs_header_level(eb) != i - 1); | |
1477 | path->nodes[i - 1] = eb; | |
1478 | path->slots[i - 1] = 0; | |
1479 | } | |
1480 | return 1; | |
1481 | } | |
1482 | ||
1483 | /* | |
1484 | * invalidate extent cache for file extents whose key in range of | |
1485 | * [min_key, max_key) | |
1486 | */ | |
1487 | static int invalidate_extent_cache(struct btrfs_root *root, | |
1488 | struct btrfs_key *min_key, | |
1489 | struct btrfs_key *max_key) | |
1490 | { | |
1491 | struct inode *inode = NULL; | |
1492 | u64 objectid; | |
1493 | u64 start, end; | |
1494 | ||
1495 | objectid = min_key->objectid; | |
1496 | while (1) { | |
1497 | cond_resched(); | |
1498 | iput(inode); | |
1499 | ||
1500 | if (objectid > max_key->objectid) | |
1501 | break; | |
1502 | ||
1503 | inode = find_next_inode(root, objectid); | |
1504 | if (!inode) | |
1505 | break; | |
1506 | ||
1507 | if (inode->i_ino > max_key->objectid) { | |
1508 | iput(inode); | |
1509 | break; | |
1510 | } | |
1511 | ||
1512 | objectid = inode->i_ino + 1; | |
1513 | if (!S_ISREG(inode->i_mode)) | |
1514 | continue; | |
1515 | ||
1516 | if (unlikely(min_key->objectid == inode->i_ino)) { | |
1517 | if (min_key->type > BTRFS_EXTENT_DATA_KEY) | |
1518 | continue; | |
1519 | if (min_key->type < BTRFS_EXTENT_DATA_KEY) | |
1520 | start = 0; | |
1521 | else { | |
1522 | start = min_key->offset; | |
1523 | WARN_ON(!IS_ALIGNED(start, root->sectorsize)); | |
1524 | } | |
1525 | } else { | |
1526 | start = 0; | |
1527 | } | |
1528 | ||
1529 | if (unlikely(max_key->objectid == inode->i_ino)) { | |
1530 | if (max_key->type < BTRFS_EXTENT_DATA_KEY) | |
1531 | continue; | |
1532 | if (max_key->type > BTRFS_EXTENT_DATA_KEY) { | |
1533 | end = (u64)-1; | |
1534 | } else { | |
1535 | if (max_key->offset == 0) | |
1536 | continue; | |
1537 | end = max_key->offset; | |
1538 | WARN_ON(!IS_ALIGNED(end, root->sectorsize)); | |
1539 | end--; | |
1540 | } | |
1541 | } else { | |
1542 | end = (u64)-1; | |
1543 | } | |
1544 | ||
1545 | /* the lock_extent waits for readpage to complete */ | |
1546 | lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
1547 | btrfs_drop_extent_cache(inode, start, end, 1); | |
1548 | unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
1549 | } | |
1550 | return 0; | |
1551 | } | |
1552 | ||
1553 | static int find_next_key(struct btrfs_path *path, int level, | |
1554 | struct btrfs_key *key) | |
1555 | ||
1556 | { | |
1557 | while (level < BTRFS_MAX_LEVEL) { | |
1558 | if (!path->nodes[level]) | |
1559 | break; | |
1560 | if (path->slots[level] + 1 < | |
1561 | btrfs_header_nritems(path->nodes[level])) { | |
1562 | btrfs_node_key_to_cpu(path->nodes[level], key, | |
1563 | path->slots[level] + 1); | |
1564 | return 0; | |
1565 | } | |
1566 | level++; | |
1567 | } | |
1568 | return 1; | |
1569 | } | |
1570 | ||
1571 | /* | |
1572 | * merge the relocated tree blocks in reloc tree with corresponding | |
1573 | * fs tree. | |
1574 | */ | |
1575 | static noinline_for_stack int merge_reloc_root(struct reloc_control *rc, | |
1576 | struct btrfs_root *root) | |
1577 | { | |
1578 | LIST_HEAD(inode_list); | |
1579 | struct btrfs_key key; | |
1580 | struct btrfs_key next_key; | |
1581 | struct btrfs_trans_handle *trans; | |
1582 | struct btrfs_root *reloc_root; | |
1583 | struct btrfs_root_item *root_item; | |
1584 | struct btrfs_path *path; | |
1585 | struct extent_buffer *leaf = NULL; | |
1586 | unsigned long nr; | |
1587 | int level; | |
1588 | int max_level; | |
1589 | int replaced = 0; | |
1590 | int ret; | |
1591 | int err = 0; | |
1592 | ||
1593 | path = btrfs_alloc_path(); | |
1594 | if (!path) | |
1595 | return -ENOMEM; | |
1596 | ||
1597 | reloc_root = root->reloc_root; | |
1598 | root_item = &reloc_root->root_item; | |
1599 | ||
1600 | if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) { | |
1601 | level = btrfs_root_level(root_item); | |
1602 | extent_buffer_get(reloc_root->node); | |
1603 | path->nodes[level] = reloc_root->node; | |
1604 | path->slots[level] = 0; | |
1605 | } else { | |
1606 | btrfs_disk_key_to_cpu(&key, &root_item->drop_progress); | |
1607 | ||
1608 | level = root_item->drop_level; | |
1609 | BUG_ON(level == 0); | |
1610 | path->lowest_level = level; | |
1611 | ret = btrfs_search_slot(NULL, reloc_root, &key, path, 0, 0); | |
1612 | if (ret < 0) { | |
1613 | btrfs_free_path(path); | |
1614 | return ret; | |
1615 | } | |
1616 | ||
1617 | btrfs_node_key_to_cpu(path->nodes[level], &next_key, | |
1618 | path->slots[level]); | |
1619 | WARN_ON(memcmp(&key, &next_key, sizeof(key))); | |
1620 | ||
1621 | btrfs_unlock_up_safe(path, 0); | |
1622 | } | |
1623 | ||
1624 | if (level == 0 && rc->stage == UPDATE_DATA_PTRS) { | |
1625 | trans = btrfs_start_transaction(root, 1); | |
1626 | ||
1627 | leaf = path->nodes[0]; | |
1628 | btrfs_item_key_to_cpu(leaf, &key, 0); | |
1629 | btrfs_release_path(reloc_root, path); | |
1630 | ||
1631 | ret = btrfs_search_slot(trans, root, &key, path, 0, 1); | |
1632 | if (ret < 0) { | |
1633 | err = ret; | |
1634 | goto out; | |
1635 | } | |
1636 | ||
1637 | leaf = path->nodes[0]; | |
1638 | btrfs_unlock_up_safe(path, 1); | |
1639 | ret = replace_file_extents(trans, rc, root, leaf, | |
1640 | &inode_list); | |
1641 | if (ret < 0) | |
1642 | err = ret; | |
1643 | goto out; | |
1644 | } | |
1645 | ||
1646 | memset(&next_key, 0, sizeof(next_key)); | |
1647 | ||
1648 | while (1) { | |
1649 | leaf = NULL; | |
1650 | replaced = 0; | |
1651 | trans = btrfs_start_transaction(root, 1); | |
1652 | max_level = level; | |
1653 | ||
1654 | ret = walk_down_reloc_tree(reloc_root, path, &level); | |
1655 | if (ret < 0) { | |
1656 | err = ret; | |
1657 | goto out; | |
1658 | } | |
1659 | if (ret > 0) | |
1660 | break; | |
1661 | ||
1662 | if (!find_next_key(path, level, &key) && | |
1663 | btrfs_comp_cpu_keys(&next_key, &key) >= 0) { | |
1664 | ret = 0; | |
1665 | } else if (level == 1 && rc->stage == UPDATE_DATA_PTRS) { | |
1666 | ret = replace_path(trans, root, reloc_root, | |
1667 | path, &next_key, &leaf, | |
1668 | level, max_level); | |
1669 | } else { | |
1670 | ret = replace_path(trans, root, reloc_root, | |
1671 | path, &next_key, NULL, | |
1672 | level, max_level); | |
1673 | } | |
1674 | if (ret < 0) { | |
1675 | err = ret; | |
1676 | goto out; | |
1677 | } | |
1678 | ||
1679 | if (ret > 0) { | |
1680 | level = ret; | |
1681 | btrfs_node_key_to_cpu(path->nodes[level], &key, | |
1682 | path->slots[level]); | |
1683 | replaced = 1; | |
1684 | } else if (leaf) { | |
1685 | /* | |
1686 | * no block got replaced, try replacing file extents | |
1687 | */ | |
1688 | btrfs_item_key_to_cpu(leaf, &key, 0); | |
1689 | ret = replace_file_extents(trans, rc, root, leaf, | |
1690 | &inode_list); | |
1691 | btrfs_tree_unlock(leaf); | |
1692 | free_extent_buffer(leaf); | |
1693 | BUG_ON(ret < 0); | |
1694 | } | |
1695 | ||
1696 | ret = walk_up_reloc_tree(reloc_root, path, &level); | |
1697 | if (ret > 0) | |
1698 | break; | |
1699 | ||
1700 | BUG_ON(level == 0); | |
1701 | /* | |
1702 | * save the merging progress in the drop_progress. | |
1703 | * this is OK since root refs == 1 in this case. | |
1704 | */ | |
1705 | btrfs_node_key(path->nodes[level], &root_item->drop_progress, | |
1706 | path->slots[level]); | |
1707 | root_item->drop_level = level; | |
1708 | ||
1709 | nr = trans->blocks_used; | |
1710 | btrfs_end_transaction(trans, root); | |
1711 | ||
1712 | btrfs_btree_balance_dirty(root, nr); | |
1713 | ||
1714 | if (replaced && rc->stage == UPDATE_DATA_PTRS) | |
1715 | invalidate_extent_cache(root, &key, &next_key); | |
1716 | } | |
1717 | ||
1718 | /* | |
1719 | * handle the case only one block in the fs tree need to be | |
1720 | * relocated and the block is tree root. | |
1721 | */ | |
1722 | leaf = btrfs_lock_root_node(root); | |
1723 | ret = btrfs_cow_block(trans, root, leaf, NULL, 0, &leaf); | |
1724 | btrfs_tree_unlock(leaf); | |
1725 | free_extent_buffer(leaf); | |
1726 | if (ret < 0) | |
1727 | err = ret; | |
1728 | out: | |
1729 | btrfs_free_path(path); | |
1730 | ||
1731 | if (err == 0) { | |
1732 | memset(&root_item->drop_progress, 0, | |
1733 | sizeof(root_item->drop_progress)); | |
1734 | root_item->drop_level = 0; | |
1735 | btrfs_set_root_refs(root_item, 0); | |
1736 | } | |
1737 | ||
1738 | nr = trans->blocks_used; | |
1739 | btrfs_end_transaction(trans, root); | |
1740 | ||
1741 | btrfs_btree_balance_dirty(root, nr); | |
1742 | ||
1743 | /* | |
1744 | * put inodes while we aren't holding the tree locks | |
1745 | */ | |
1746 | while (!list_empty(&inode_list)) { | |
1747 | struct inodevec *ivec; | |
1748 | ivec = list_entry(inode_list.next, struct inodevec, list); | |
1749 | list_del(&ivec->list); | |
1750 | while (ivec->nr > 0) { | |
1751 | ivec->nr--; | |
1752 | iput(ivec->inode[ivec->nr]); | |
1753 | } | |
1754 | kfree(ivec); | |
1755 | } | |
1756 | ||
1757 | if (replaced && rc->stage == UPDATE_DATA_PTRS) | |
1758 | invalidate_extent_cache(root, &key, &next_key); | |
1759 | ||
1760 | return err; | |
1761 | } | |
1762 | ||
1763 | /* | |
1764 | * callback for the work threads. | |
1765 | * this function merges reloc tree with corresponding fs tree, | |
1766 | * and then drops the reloc tree. | |
1767 | */ | |
1768 | static void merge_func(struct btrfs_work *work) | |
1769 | { | |
1770 | struct btrfs_trans_handle *trans; | |
1771 | struct btrfs_root *root; | |
1772 | struct btrfs_root *reloc_root; | |
1773 | struct async_merge *async; | |
1774 | ||
1775 | async = container_of(work, struct async_merge, work); | |
1776 | reloc_root = async->root; | |
1777 | ||
1778 | if (btrfs_root_refs(&reloc_root->root_item) > 0) { | |
1779 | root = read_fs_root(reloc_root->fs_info, | |
1780 | reloc_root->root_key.offset); | |
1781 | BUG_ON(IS_ERR(root)); | |
1782 | BUG_ON(root->reloc_root != reloc_root); | |
1783 | ||
1784 | merge_reloc_root(async->rc, root); | |
1785 | ||
1786 | trans = btrfs_start_transaction(root, 1); | |
1787 | btrfs_update_reloc_root(trans, root); | |
1788 | btrfs_end_transaction(trans, root); | |
1789 | } | |
1790 | ||
2c47e605 | 1791 | btrfs_drop_snapshot(reloc_root, 0); |
5d4f98a2 YZ |
1792 | |
1793 | if (atomic_dec_and_test(async->num_pending)) | |
1794 | complete(async->done); | |
1795 | ||
1796 | kfree(async); | |
1797 | } | |
1798 | ||
1799 | static int merge_reloc_roots(struct reloc_control *rc) | |
1800 | { | |
1801 | struct async_merge *async; | |
1802 | struct btrfs_root *root; | |
1803 | struct completion done; | |
1804 | atomic_t num_pending; | |
1805 | ||
1806 | init_completion(&done); | |
1807 | atomic_set(&num_pending, 1); | |
1808 | ||
1809 | while (!list_empty(&rc->reloc_roots)) { | |
1810 | root = list_entry(rc->reloc_roots.next, | |
1811 | struct btrfs_root, root_list); | |
1812 | list_del_init(&root->root_list); | |
1813 | ||
1814 | async = kmalloc(sizeof(*async), GFP_NOFS); | |
1815 | BUG_ON(!async); | |
1816 | async->work.func = merge_func; | |
1817 | async->work.flags = 0; | |
1818 | async->rc = rc; | |
1819 | async->root = root; | |
1820 | async->done = &done; | |
1821 | async->num_pending = &num_pending; | |
1822 | atomic_inc(&num_pending); | |
1823 | btrfs_queue_worker(&rc->workers, &async->work); | |
1824 | } | |
1825 | ||
1826 | if (!atomic_dec_and_test(&num_pending)) | |
1827 | wait_for_completion(&done); | |
1828 | ||
1829 | BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root)); | |
1830 | return 0; | |
1831 | } | |
1832 | ||
1833 | static void free_block_list(struct rb_root *blocks) | |
1834 | { | |
1835 | struct tree_block *block; | |
1836 | struct rb_node *rb_node; | |
1837 | while ((rb_node = rb_first(blocks))) { | |
1838 | block = rb_entry(rb_node, struct tree_block, rb_node); | |
1839 | rb_erase(rb_node, blocks); | |
1840 | kfree(block); | |
1841 | } | |
1842 | } | |
1843 | ||
1844 | static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans, | |
1845 | struct btrfs_root *reloc_root) | |
1846 | { | |
1847 | struct btrfs_root *root; | |
1848 | ||
1849 | if (reloc_root->last_trans == trans->transid) | |
1850 | return 0; | |
1851 | ||
1852 | root = read_fs_root(reloc_root->fs_info, reloc_root->root_key.offset); | |
1853 | BUG_ON(IS_ERR(root)); | |
1854 | BUG_ON(root->reloc_root != reloc_root); | |
1855 | ||
1856 | return btrfs_record_root_in_trans(trans, root); | |
1857 | } | |
1858 | ||
1859 | /* | |
1860 | * select one tree from trees that references the block. | |
1861 | * for blocks in refernce counted trees, we preper reloc tree. | |
1862 | * if no reloc tree found and reloc_only is true, NULL is returned. | |
1863 | */ | |
1864 | static struct btrfs_root *__select_one_root(struct btrfs_trans_handle *trans, | |
1865 | struct backref_node *node, | |
1866 | struct backref_edge *edges[], | |
1867 | int *nr, int reloc_only) | |
1868 | { | |
1869 | struct backref_node *next; | |
1870 | struct btrfs_root *root; | |
1871 | int index; | |
1872 | int loop = 0; | |
1873 | again: | |
1874 | index = 0; | |
1875 | next = node; | |
1876 | while (1) { | |
1877 | cond_resched(); | |
1878 | next = walk_up_backref(next, edges, &index); | |
1879 | root = next->root; | |
1880 | if (!root) { | |
1881 | BUG_ON(!node->old_root); | |
1882 | goto skip; | |
1883 | } | |
1884 | ||
1885 | /* no other choice for non-refernce counted tree */ | |
1886 | if (!root->ref_cows) { | |
1887 | BUG_ON(reloc_only); | |
1888 | break; | |
1889 | } | |
1890 | ||
1891 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { | |
1892 | record_reloc_root_in_trans(trans, root); | |
1893 | break; | |
1894 | } | |
1895 | ||
1896 | if (loop) { | |
1897 | btrfs_record_root_in_trans(trans, root); | |
1898 | break; | |
1899 | } | |
1900 | ||
1901 | if (reloc_only || next != node) { | |
1902 | if (!root->reloc_root) | |
1903 | btrfs_record_root_in_trans(trans, root); | |
1904 | root = root->reloc_root; | |
1905 | /* | |
1906 | * if the reloc tree was created in current | |
1907 | * transation, there is no node in backref tree | |
1908 | * corresponds to the root of the reloc tree. | |
1909 | */ | |
1910 | if (btrfs_root_last_snapshot(&root->root_item) == | |
1911 | trans->transid - 1) | |
1912 | break; | |
1913 | } | |
1914 | skip: | |
1915 | root = NULL; | |
1916 | next = walk_down_backref(edges, &index); | |
1917 | if (!next || next->level <= node->level) | |
1918 | break; | |
1919 | } | |
1920 | ||
1921 | if (!root && !loop && !reloc_only) { | |
1922 | loop = 1; | |
1923 | goto again; | |
1924 | } | |
1925 | ||
1926 | if (root) | |
1927 | *nr = index; | |
1928 | else | |
1929 | *nr = 0; | |
1930 | ||
1931 | return root; | |
1932 | } | |
1933 | ||
1934 | static noinline_for_stack | |
1935 | struct btrfs_root *select_one_root(struct btrfs_trans_handle *trans, | |
1936 | struct backref_node *node) | |
1937 | { | |
1938 | struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; | |
1939 | int nr; | |
1940 | return __select_one_root(trans, node, edges, &nr, 0); | |
1941 | } | |
1942 | ||
1943 | static noinline_for_stack | |
1944 | struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans, | |
1945 | struct backref_node *node, | |
1946 | struct backref_edge *edges[], int *nr) | |
1947 | { | |
1948 | return __select_one_root(trans, node, edges, nr, 1); | |
1949 | } | |
1950 | ||
1951 | static void grab_path_buffers(struct btrfs_path *path, | |
1952 | struct backref_node *node, | |
1953 | struct backref_edge *edges[], int nr) | |
1954 | { | |
1955 | int i = 0; | |
1956 | while (1) { | |
1957 | drop_node_buffer(node); | |
1958 | node->eb = path->nodes[node->level]; | |
1959 | BUG_ON(!node->eb); | |
1960 | if (path->locks[node->level]) | |
1961 | node->locked = 1; | |
1962 | path->nodes[node->level] = NULL; | |
1963 | path->locks[node->level] = 0; | |
1964 | ||
1965 | if (i >= nr) | |
1966 | break; | |
1967 | ||
1968 | edges[i]->blockptr = node->eb->start; | |
1969 | node = edges[i]->node[UPPER]; | |
1970 | i++; | |
1971 | } | |
1972 | } | |
1973 | ||
1974 | /* | |
1975 | * relocate a block tree, and then update pointers in upper level | |
1976 | * blocks that reference the block to point to the new location. | |
1977 | * | |
1978 | * if called by link_to_upper, the block has already been relocated. | |
1979 | * in that case this function just updates pointers. | |
1980 | */ | |
1981 | static int do_relocation(struct btrfs_trans_handle *trans, | |
1982 | struct backref_node *node, | |
1983 | struct btrfs_key *key, | |
1984 | struct btrfs_path *path, int lowest) | |
1985 | { | |
1986 | struct backref_node *upper; | |
1987 | struct backref_edge *edge; | |
1988 | struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; | |
1989 | struct btrfs_root *root; | |
1990 | struct extent_buffer *eb; | |
1991 | u32 blocksize; | |
1992 | u64 bytenr; | |
1993 | u64 generation; | |
1994 | int nr; | |
1995 | int slot; | |
1996 | int ret; | |
1997 | int err = 0; | |
1998 | ||
1999 | BUG_ON(lowest && node->eb); | |
2000 | ||
2001 | path->lowest_level = node->level + 1; | |
2002 | list_for_each_entry(edge, &node->upper, list[LOWER]) { | |
2003 | cond_resched(); | |
2004 | if (node->eb && node->eb->start == edge->blockptr) | |
2005 | continue; | |
2006 | ||
2007 | upper = edge->node[UPPER]; | |
2008 | root = select_reloc_root(trans, upper, edges, &nr); | |
2009 | if (!root) | |
2010 | continue; | |
2011 | ||
2012 | if (upper->eb && !upper->locked) | |
2013 | drop_node_buffer(upper); | |
2014 | ||
2015 | if (!upper->eb) { | |
2016 | ret = btrfs_search_slot(trans, root, key, path, 0, 1); | |
2017 | if (ret < 0) { | |
2018 | err = ret; | |
2019 | break; | |
2020 | } | |
2021 | BUG_ON(ret > 0); | |
2022 | ||
2023 | slot = path->slots[upper->level]; | |
2024 | ||
2025 | btrfs_unlock_up_safe(path, upper->level + 1); | |
2026 | grab_path_buffers(path, upper, edges, nr); | |
2027 | ||
2028 | btrfs_release_path(NULL, path); | |
2029 | } else { | |
2030 | ret = btrfs_bin_search(upper->eb, key, upper->level, | |
2031 | &slot); | |
2032 | BUG_ON(ret); | |
2033 | } | |
2034 | ||
2035 | bytenr = btrfs_node_blockptr(upper->eb, slot); | |
2036 | if (!lowest) { | |
2037 | if (node->eb->start == bytenr) { | |
2038 | btrfs_tree_unlock(upper->eb); | |
2039 | upper->locked = 0; | |
2040 | continue; | |
2041 | } | |
2042 | } else { | |
2043 | BUG_ON(node->bytenr != bytenr); | |
2044 | } | |
2045 | ||
2046 | blocksize = btrfs_level_size(root, node->level); | |
2047 | generation = btrfs_node_ptr_generation(upper->eb, slot); | |
2048 | eb = read_tree_block(root, bytenr, blocksize, generation); | |
2049 | btrfs_tree_lock(eb); | |
2050 | btrfs_set_lock_blocking(eb); | |
2051 | ||
2052 | if (!node->eb) { | |
2053 | ret = btrfs_cow_block(trans, root, eb, upper->eb, | |
2054 | slot, &eb); | |
2055 | if (ret < 0) { | |
2056 | err = ret; | |
2057 | break; | |
2058 | } | |
2059 | btrfs_set_lock_blocking(eb); | |
2060 | node->eb = eb; | |
2061 | node->locked = 1; | |
2062 | } else { | |
2063 | btrfs_set_node_blockptr(upper->eb, slot, | |
2064 | node->eb->start); | |
2065 | btrfs_set_node_ptr_generation(upper->eb, slot, | |
2066 | trans->transid); | |
2067 | btrfs_mark_buffer_dirty(upper->eb); | |
2068 | ||
2069 | ret = btrfs_inc_extent_ref(trans, root, | |
2070 | node->eb->start, blocksize, | |
2071 | upper->eb->start, | |
2072 | btrfs_header_owner(upper->eb), | |
2073 | node->level, 0); | |
2074 | BUG_ON(ret); | |
2075 | ||
2076 | ret = btrfs_drop_subtree(trans, root, eb, upper->eb); | |
2077 | BUG_ON(ret); | |
5d4f98a2 YZ |
2078 | } |
2079 | if (!lowest) { | |
2080 | btrfs_tree_unlock(upper->eb); | |
2081 | upper->locked = 0; | |
2082 | } | |
2083 | } | |
2084 | path->lowest_level = 0; | |
2085 | return err; | |
2086 | } | |
2087 | ||
2088 | static int link_to_upper(struct btrfs_trans_handle *trans, | |
2089 | struct backref_node *node, | |
2090 | struct btrfs_path *path) | |
2091 | { | |
2092 | struct btrfs_key key; | |
2093 | if (!node->eb || list_empty(&node->upper)) | |
2094 | return 0; | |
2095 | ||
2096 | btrfs_node_key_to_cpu(node->eb, &key, 0); | |
2097 | return do_relocation(trans, node, &key, path, 0); | |
2098 | } | |
2099 | ||
2100 | static int finish_pending_nodes(struct btrfs_trans_handle *trans, | |
2101 | struct backref_cache *cache, | |
2102 | struct btrfs_path *path) | |
2103 | { | |
2104 | struct backref_node *node; | |
2105 | int level; | |
2106 | int ret; | |
2107 | int err = 0; | |
2108 | ||
2109 | for (level = 0; level < BTRFS_MAX_LEVEL; level++) { | |
2110 | while (!list_empty(&cache->pending[level])) { | |
2111 | node = list_entry(cache->pending[level].next, | |
2112 | struct backref_node, lower); | |
2113 | BUG_ON(node->level != level); | |
2114 | ||
2115 | ret = link_to_upper(trans, node, path); | |
2116 | if (ret < 0) | |
2117 | err = ret; | |
2118 | /* | |
2119 | * this remove the node from the pending list and | |
2120 | * may add some other nodes to the level + 1 | |
2121 | * pending list | |
2122 | */ | |
2123 | remove_backref_node(cache, node); | |
2124 | } | |
2125 | } | |
2126 | BUG_ON(!RB_EMPTY_ROOT(&cache->rb_root)); | |
2127 | return err; | |
2128 | } | |
2129 | ||
2130 | static void mark_block_processed(struct reloc_control *rc, | |
2131 | struct backref_node *node) | |
2132 | { | |
2133 | u32 blocksize; | |
2134 | if (node->level == 0 || | |
2135 | in_block_group(node->bytenr, rc->block_group)) { | |
2136 | blocksize = btrfs_level_size(rc->extent_root, node->level); | |
2137 | set_extent_bits(&rc->processed_blocks, node->bytenr, | |
2138 | node->bytenr + blocksize - 1, EXTENT_DIRTY, | |
2139 | GFP_NOFS); | |
2140 | } | |
2141 | node->processed = 1; | |
2142 | } | |
2143 | ||
2144 | /* | |
2145 | * mark a block and all blocks directly/indirectly reference the block | |
2146 | * as processed. | |
2147 | */ | |
2148 | static void update_processed_blocks(struct reloc_control *rc, | |
2149 | struct backref_node *node) | |
2150 | { | |
2151 | struct backref_node *next = node; | |
2152 | struct backref_edge *edge; | |
2153 | struct backref_edge *edges[BTRFS_MAX_LEVEL - 1]; | |
2154 | int index = 0; | |
2155 | ||
2156 | while (next) { | |
2157 | cond_resched(); | |
2158 | while (1) { | |
2159 | if (next->processed) | |
2160 | break; | |
2161 | ||
2162 | mark_block_processed(rc, next); | |
2163 | ||
2164 | if (list_empty(&next->upper)) | |
2165 | break; | |
2166 | ||
2167 | edge = list_entry(next->upper.next, | |
2168 | struct backref_edge, list[LOWER]); | |
2169 | edges[index++] = edge; | |
2170 | next = edge->node[UPPER]; | |
2171 | } | |
2172 | next = walk_down_backref(edges, &index); | |
2173 | } | |
2174 | } | |
2175 | ||
2176 | static int tree_block_processed(u64 bytenr, u32 blocksize, | |
2177 | struct reloc_control *rc) | |
2178 | { | |
2179 | if (test_range_bit(&rc->processed_blocks, bytenr, | |
2180 | bytenr + blocksize - 1, EXTENT_DIRTY, 1)) | |
2181 | return 1; | |
2182 | return 0; | |
2183 | } | |
2184 | ||
2185 | /* | |
2186 | * check if there are any file extent pointers in the leaf point to | |
2187 | * data require processing | |
2188 | */ | |
2189 | static int check_file_extents(struct reloc_control *rc, | |
2190 | u64 bytenr, u32 blocksize, u64 ptr_gen) | |
2191 | { | |
2192 | struct btrfs_key found_key; | |
2193 | struct btrfs_file_extent_item *fi; | |
2194 | struct extent_buffer *leaf; | |
2195 | u32 nritems; | |
2196 | int i; | |
2197 | int ret = 0; | |
2198 | ||
2199 | leaf = read_tree_block(rc->extent_root, bytenr, blocksize, ptr_gen); | |
2200 | ||
2201 | nritems = btrfs_header_nritems(leaf); | |
2202 | for (i = 0; i < nritems; i++) { | |
2203 | cond_resched(); | |
2204 | btrfs_item_key_to_cpu(leaf, &found_key, i); | |
2205 | if (found_key.type != BTRFS_EXTENT_DATA_KEY) | |
2206 | continue; | |
2207 | fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item); | |
2208 | if (btrfs_file_extent_type(leaf, fi) == | |
2209 | BTRFS_FILE_EXTENT_INLINE) | |
2210 | continue; | |
2211 | bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); | |
2212 | if (bytenr == 0) | |
2213 | continue; | |
2214 | if (in_block_group(bytenr, rc->block_group)) { | |
2215 | ret = 1; | |
2216 | break; | |
2217 | } | |
2218 | } | |
2219 | free_extent_buffer(leaf); | |
2220 | return ret; | |
2221 | } | |
2222 | ||
2223 | /* | |
2224 | * scan child blocks of a given block to find blocks require processing | |
2225 | */ | |
2226 | static int add_child_blocks(struct btrfs_trans_handle *trans, | |
2227 | struct reloc_control *rc, | |
2228 | struct backref_node *node, | |
2229 | struct rb_root *blocks) | |
2230 | { | |
2231 | struct tree_block *block; | |
2232 | struct rb_node *rb_node; | |
2233 | u64 bytenr; | |
2234 | u64 ptr_gen; | |
2235 | u32 blocksize; | |
2236 | u32 nritems; | |
2237 | int i; | |
2238 | int err = 0; | |
2239 | ||
2240 | nritems = btrfs_header_nritems(node->eb); | |
2241 | blocksize = btrfs_level_size(rc->extent_root, node->level - 1); | |
2242 | for (i = 0; i < nritems; i++) { | |
2243 | cond_resched(); | |
2244 | bytenr = btrfs_node_blockptr(node->eb, i); | |
2245 | ptr_gen = btrfs_node_ptr_generation(node->eb, i); | |
2246 | if (ptr_gen == trans->transid) | |
2247 | continue; | |
2248 | if (!in_block_group(bytenr, rc->block_group) && | |
2249 | (node->level > 1 || rc->stage == MOVE_DATA_EXTENTS)) | |
2250 | continue; | |
2251 | if (tree_block_processed(bytenr, blocksize, rc)) | |
2252 | continue; | |
2253 | ||
2254 | readahead_tree_block(rc->extent_root, | |
2255 | bytenr, blocksize, ptr_gen); | |
2256 | } | |
2257 | ||
2258 | for (i = 0; i < nritems; i++) { | |
2259 | cond_resched(); | |
2260 | bytenr = btrfs_node_blockptr(node->eb, i); | |
2261 | ptr_gen = btrfs_node_ptr_generation(node->eb, i); | |
2262 | if (ptr_gen == trans->transid) | |
2263 | continue; | |
2264 | if (!in_block_group(bytenr, rc->block_group) && | |
2265 | (node->level > 1 || rc->stage == MOVE_DATA_EXTENTS)) | |
2266 | continue; | |
2267 | if (tree_block_processed(bytenr, blocksize, rc)) | |
2268 | continue; | |
2269 | if (!in_block_group(bytenr, rc->block_group) && | |
2270 | !check_file_extents(rc, bytenr, blocksize, ptr_gen)) | |
2271 | continue; | |
2272 | ||
2273 | block = kmalloc(sizeof(*block), GFP_NOFS); | |
2274 | if (!block) { | |
2275 | err = -ENOMEM; | |
2276 | break; | |
2277 | } | |
2278 | block->bytenr = bytenr; | |
2279 | btrfs_node_key_to_cpu(node->eb, &block->key, i); | |
2280 | block->level = node->level - 1; | |
2281 | block->key_ready = 1; | |
2282 | rb_node = tree_insert(blocks, block->bytenr, &block->rb_node); | |
2283 | BUG_ON(rb_node); | |
2284 | } | |
2285 | if (err) | |
2286 | free_block_list(blocks); | |
2287 | return err; | |
2288 | } | |
2289 | ||
2290 | /* | |
2291 | * find adjacent blocks require processing | |
2292 | */ | |
2293 | static noinline_for_stack | |
2294 | int add_adjacent_blocks(struct btrfs_trans_handle *trans, | |
2295 | struct reloc_control *rc, | |
2296 | struct backref_cache *cache, | |
2297 | struct rb_root *blocks, int level, | |
2298 | struct backref_node **upper) | |
2299 | { | |
2300 | struct backref_node *node; | |
2301 | int ret = 0; | |
2302 | ||
2303 | WARN_ON(!list_empty(&cache->pending[level])); | |
2304 | ||
2305 | if (list_empty(&cache->pending[level + 1])) | |
2306 | return 1; | |
2307 | ||
2308 | node = list_entry(cache->pending[level + 1].next, | |
2309 | struct backref_node, lower); | |
2310 | if (node->eb) | |
2311 | ret = add_child_blocks(trans, rc, node, blocks); | |
2312 | ||
2313 | *upper = node; | |
2314 | return ret; | |
2315 | } | |
2316 | ||
2317 | static int get_tree_block_key(struct reloc_control *rc, | |
2318 | struct tree_block *block) | |
2319 | { | |
2320 | struct extent_buffer *eb; | |
2321 | ||
2322 | BUG_ON(block->key_ready); | |
2323 | eb = read_tree_block(rc->extent_root, block->bytenr, | |
2324 | block->key.objectid, block->key.offset); | |
2325 | WARN_ON(btrfs_header_level(eb) != block->level); | |
2326 | if (block->level == 0) | |
2327 | btrfs_item_key_to_cpu(eb, &block->key, 0); | |
2328 | else | |
2329 | btrfs_node_key_to_cpu(eb, &block->key, 0); | |
2330 | free_extent_buffer(eb); | |
2331 | block->key_ready = 1; | |
2332 | return 0; | |
2333 | } | |
2334 | ||
2335 | static int reada_tree_block(struct reloc_control *rc, | |
2336 | struct tree_block *block) | |
2337 | { | |
2338 | BUG_ON(block->key_ready); | |
2339 | readahead_tree_block(rc->extent_root, block->bytenr, | |
2340 | block->key.objectid, block->key.offset); | |
2341 | return 0; | |
2342 | } | |
2343 | ||
2344 | /* | |
2345 | * helper function to relocate a tree block | |
2346 | */ | |
2347 | static int relocate_tree_block(struct btrfs_trans_handle *trans, | |
2348 | struct reloc_control *rc, | |
2349 | struct backref_node *node, | |
2350 | struct btrfs_key *key, | |
2351 | struct btrfs_path *path) | |
2352 | { | |
2353 | struct btrfs_root *root; | |
2354 | int ret; | |
2355 | ||
2356 | root = select_one_root(trans, node); | |
2357 | if (unlikely(!root)) { | |
2358 | rc->found_old_snapshot = 1; | |
2359 | update_processed_blocks(rc, node); | |
2360 | return 0; | |
2361 | } | |
2362 | ||
2363 | if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) { | |
2364 | ret = do_relocation(trans, node, key, path, 1); | |
2365 | if (ret < 0) | |
2366 | goto out; | |
2367 | if (node->level == 0 && rc->stage == UPDATE_DATA_PTRS) { | |
2368 | ret = replace_file_extents(trans, rc, root, | |
2369 | node->eb, NULL); | |
2370 | if (ret < 0) | |
2371 | goto out; | |
2372 | } | |
2373 | drop_node_buffer(node); | |
2374 | } else if (!root->ref_cows) { | |
2375 | path->lowest_level = node->level; | |
2376 | ret = btrfs_search_slot(trans, root, key, path, 0, 1); | |
2377 | btrfs_release_path(root, path); | |
2378 | if (ret < 0) | |
2379 | goto out; | |
2380 | } else if (root != node->root) { | |
2381 | WARN_ON(node->level > 0 || rc->stage != UPDATE_DATA_PTRS); | |
2382 | } | |
2383 | ||
2384 | update_processed_blocks(rc, node); | |
2385 | ret = 0; | |
2386 | out: | |
2387 | drop_node_buffer(node); | |
2388 | return ret; | |
2389 | } | |
2390 | ||
2391 | /* | |
2392 | * relocate a list of blocks | |
2393 | */ | |
2394 | static noinline_for_stack | |
2395 | int relocate_tree_blocks(struct btrfs_trans_handle *trans, | |
2396 | struct reloc_control *rc, struct rb_root *blocks) | |
2397 | { | |
2398 | struct backref_cache *cache; | |
2399 | struct backref_node *node; | |
2400 | struct btrfs_path *path; | |
2401 | struct tree_block *block; | |
2402 | struct rb_node *rb_node; | |
2403 | int level = -1; | |
2404 | int ret; | |
2405 | int err = 0; | |
2406 | ||
2407 | path = btrfs_alloc_path(); | |
2408 | if (!path) | |
2409 | return -ENOMEM; | |
2410 | ||
2411 | cache = kmalloc(sizeof(*cache), GFP_NOFS); | |
2412 | if (!cache) { | |
2413 | btrfs_free_path(path); | |
2414 | return -ENOMEM; | |
2415 | } | |
2416 | ||
2417 | backref_cache_init(cache); | |
2418 | ||
2419 | rb_node = rb_first(blocks); | |
2420 | while (rb_node) { | |
2421 | block = rb_entry(rb_node, struct tree_block, rb_node); | |
2422 | if (level == -1) | |
2423 | level = block->level; | |
2424 | else | |
2425 | BUG_ON(level != block->level); | |
2426 | if (!block->key_ready) | |
2427 | reada_tree_block(rc, block); | |
2428 | rb_node = rb_next(rb_node); | |
2429 | } | |
2430 | ||
2431 | rb_node = rb_first(blocks); | |
2432 | while (rb_node) { | |
2433 | block = rb_entry(rb_node, struct tree_block, rb_node); | |
2434 | if (!block->key_ready) | |
2435 | get_tree_block_key(rc, block); | |
2436 | rb_node = rb_next(rb_node); | |
2437 | } | |
2438 | ||
2439 | rb_node = rb_first(blocks); | |
2440 | while (rb_node) { | |
2441 | block = rb_entry(rb_node, struct tree_block, rb_node); | |
2442 | ||
2443 | node = build_backref_tree(rc, cache, &block->key, | |
2444 | block->level, block->bytenr); | |
2445 | if (IS_ERR(node)) { | |
2446 | err = PTR_ERR(node); | |
2447 | goto out; | |
2448 | } | |
2449 | ||
2450 | ret = relocate_tree_block(trans, rc, node, &block->key, | |
2451 | path); | |
2452 | if (ret < 0) { | |
2453 | err = ret; | |
2454 | goto out; | |
2455 | } | |
2456 | remove_backref_node(cache, node); | |
2457 | rb_node = rb_next(rb_node); | |
2458 | } | |
2459 | ||
2460 | if (level > 0) | |
2461 | goto out; | |
2462 | ||
2463 | free_block_list(blocks); | |
2464 | ||
2465 | /* | |
2466 | * now backrefs of some upper level tree blocks have been cached, | |
2467 | * try relocating blocks referenced by these upper level blocks. | |
2468 | */ | |
2469 | while (1) { | |
2470 | struct backref_node *upper = NULL; | |
2471 | if (trans->transaction->in_commit || | |
2472 | trans->transaction->delayed_refs.flushing) | |
2473 | break; | |
2474 | ||
2475 | ret = add_adjacent_blocks(trans, rc, cache, blocks, level, | |
2476 | &upper); | |
2477 | if (ret < 0) | |
2478 | err = ret; | |
2479 | if (ret != 0) | |
2480 | break; | |
2481 | ||
2482 | rb_node = rb_first(blocks); | |
2483 | while (rb_node) { | |
2484 | block = rb_entry(rb_node, struct tree_block, rb_node); | |
2485 | if (trans->transaction->in_commit || | |
2486 | trans->transaction->delayed_refs.flushing) | |
2487 | goto out; | |
2488 | BUG_ON(!block->key_ready); | |
2489 | node = build_backref_tree(rc, cache, &block->key, | |
2490 | level, block->bytenr); | |
2491 | if (IS_ERR(node)) { | |
2492 | err = PTR_ERR(node); | |
2493 | goto out; | |
2494 | } | |
2495 | ||
2496 | ret = relocate_tree_block(trans, rc, node, | |
2497 | &block->key, path); | |
2498 | if (ret < 0) { | |
2499 | err = ret; | |
2500 | goto out; | |
2501 | } | |
2502 | remove_backref_node(cache, node); | |
2503 | rb_node = rb_next(rb_node); | |
2504 | } | |
2505 | free_block_list(blocks); | |
2506 | ||
2507 | if (upper) { | |
2508 | ret = link_to_upper(trans, upper, path); | |
2509 | if (ret < 0) { | |
2510 | err = ret; | |
2511 | break; | |
2512 | } | |
2513 | remove_backref_node(cache, upper); | |
2514 | } | |
2515 | } | |
2516 | out: | |
2517 | free_block_list(blocks); | |
2518 | ||
2519 | ret = finish_pending_nodes(trans, cache, path); | |
2520 | if (ret < 0) | |
2521 | err = ret; | |
2522 | ||
2523 | kfree(cache); | |
2524 | btrfs_free_path(path); | |
2525 | return err; | |
2526 | } | |
2527 | ||
2528 | static noinline_for_stack | |
2529 | int relocate_inode_pages(struct inode *inode, u64 start, u64 len) | |
2530 | { | |
2531 | u64 page_start; | |
2532 | u64 page_end; | |
2533 | unsigned long i; | |
2534 | unsigned long first_index; | |
2535 | unsigned long last_index; | |
2536 | unsigned int total_read = 0; | |
2537 | unsigned int total_dirty = 0; | |
2538 | struct page *page; | |
2539 | struct file_ra_state *ra; | |
2540 | struct btrfs_ordered_extent *ordered; | |
2541 | struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree; | |
2542 | int ret = 0; | |
2543 | ||
2544 | ra = kzalloc(sizeof(*ra), GFP_NOFS); | |
2545 | if (!ra) | |
2546 | return -ENOMEM; | |
2547 | ||
2548 | mutex_lock(&inode->i_mutex); | |
2549 | first_index = start >> PAGE_CACHE_SHIFT; | |
2550 | last_index = (start + len - 1) >> PAGE_CACHE_SHIFT; | |
2551 | ||
2552 | /* make sure the dirty trick played by the caller work */ | |
2553 | ret = invalidate_inode_pages2_range(inode->i_mapping, | |
2554 | first_index, last_index); | |
2555 | if (ret) | |
2556 | goto out_unlock; | |
2557 | ||
2558 | file_ra_state_init(ra, inode->i_mapping); | |
2559 | ||
2560 | for (i = first_index ; i <= last_index; i++) { | |
2561 | if (total_read % ra->ra_pages == 0) { | |
2562 | btrfs_force_ra(inode->i_mapping, ra, NULL, i, | |
2563 | min(last_index, ra->ra_pages + i - 1)); | |
2564 | } | |
2565 | total_read++; | |
2566 | again: | |
2567 | if (((u64)i << PAGE_CACHE_SHIFT) > i_size_read(inode)) | |
2568 | BUG_ON(1); | |
2569 | page = grab_cache_page(inode->i_mapping, i); | |
2570 | if (!page) { | |
2571 | ret = -ENOMEM; | |
2572 | goto out_unlock; | |
2573 | } | |
2574 | if (!PageUptodate(page)) { | |
2575 | btrfs_readpage(NULL, page); | |
2576 | lock_page(page); | |
2577 | if (!PageUptodate(page)) { | |
2578 | unlock_page(page); | |
2579 | page_cache_release(page); | |
2580 | ret = -EIO; | |
2581 | goto out_unlock; | |
2582 | } | |
2583 | } | |
2584 | wait_on_page_writeback(page); | |
2585 | ||
2586 | page_start = (u64)page->index << PAGE_CACHE_SHIFT; | |
2587 | page_end = page_start + PAGE_CACHE_SIZE - 1; | |
2588 | lock_extent(io_tree, page_start, page_end, GFP_NOFS); | |
2589 | ||
2590 | ordered = btrfs_lookup_ordered_extent(inode, page_start); | |
2591 | if (ordered) { | |
2592 | unlock_extent(io_tree, page_start, page_end, GFP_NOFS); | |
2593 | unlock_page(page); | |
2594 | page_cache_release(page); | |
2595 | btrfs_start_ordered_extent(inode, ordered, 1); | |
2596 | btrfs_put_ordered_extent(ordered); | |
2597 | goto again; | |
2598 | } | |
2599 | set_page_extent_mapped(page); | |
2600 | ||
2601 | if (i == first_index) | |
2602 | set_extent_bits(io_tree, page_start, page_end, | |
2603 | EXTENT_BOUNDARY, GFP_NOFS); | |
2604 | btrfs_set_extent_delalloc(inode, page_start, page_end); | |
2605 | ||
2606 | set_page_dirty(page); | |
2607 | total_dirty++; | |
2608 | ||
2609 | unlock_extent(io_tree, page_start, page_end, GFP_NOFS); | |
2610 | unlock_page(page); | |
2611 | page_cache_release(page); | |
2612 | } | |
2613 | out_unlock: | |
2614 | mutex_unlock(&inode->i_mutex); | |
2615 | kfree(ra); | |
2616 | balance_dirty_pages_ratelimited_nr(inode->i_mapping, total_dirty); | |
2617 | return ret; | |
2618 | } | |
2619 | ||
2620 | static noinline_for_stack | |
2621 | int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key) | |
2622 | { | |
2623 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
2624 | struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; | |
2625 | struct extent_map *em; | |
2626 | u64 start = extent_key->objectid - BTRFS_I(inode)->index_cnt; | |
2627 | u64 end = start + extent_key->offset - 1; | |
2628 | ||
2629 | em = alloc_extent_map(GFP_NOFS); | |
2630 | em->start = start; | |
2631 | em->len = extent_key->offset; | |
2632 | em->block_len = extent_key->offset; | |
2633 | em->block_start = extent_key->objectid; | |
2634 | em->bdev = root->fs_info->fs_devices->latest_bdev; | |
2635 | set_bit(EXTENT_FLAG_PINNED, &em->flags); | |
2636 | ||
2637 | /* setup extent map to cheat btrfs_readpage */ | |
2638 | lock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
2639 | while (1) { | |
2640 | int ret; | |
2641 | spin_lock(&em_tree->lock); | |
2642 | ret = add_extent_mapping(em_tree, em); | |
2643 | spin_unlock(&em_tree->lock); | |
2644 | if (ret != -EEXIST) { | |
2645 | free_extent_map(em); | |
2646 | break; | |
2647 | } | |
2648 | btrfs_drop_extent_cache(inode, start, end, 0); | |
2649 | } | |
2650 | unlock_extent(&BTRFS_I(inode)->io_tree, start, end, GFP_NOFS); | |
2651 | ||
2652 | return relocate_inode_pages(inode, start, extent_key->offset); | |
2653 | } | |
2654 | ||
2655 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
2656 | static int get_ref_objectid_v0(struct reloc_control *rc, | |
2657 | struct btrfs_path *path, | |
2658 | struct btrfs_key *extent_key, | |
2659 | u64 *ref_objectid, int *path_change) | |
2660 | { | |
2661 | struct btrfs_key key; | |
2662 | struct extent_buffer *leaf; | |
2663 | struct btrfs_extent_ref_v0 *ref0; | |
2664 | int ret; | |
2665 | int slot; | |
2666 | ||
2667 | leaf = path->nodes[0]; | |
2668 | slot = path->slots[0]; | |
2669 | while (1) { | |
2670 | if (slot >= btrfs_header_nritems(leaf)) { | |
2671 | ret = btrfs_next_leaf(rc->extent_root, path); | |
2672 | if (ret < 0) | |
2673 | return ret; | |
2674 | BUG_ON(ret > 0); | |
2675 | leaf = path->nodes[0]; | |
2676 | slot = path->slots[0]; | |
2677 | if (path_change) | |
2678 | *path_change = 1; | |
2679 | } | |
2680 | btrfs_item_key_to_cpu(leaf, &key, slot); | |
2681 | if (key.objectid != extent_key->objectid) | |
2682 | return -ENOENT; | |
2683 | ||
2684 | if (key.type != BTRFS_EXTENT_REF_V0_KEY) { | |
2685 | slot++; | |
2686 | continue; | |
2687 | } | |
2688 | ref0 = btrfs_item_ptr(leaf, slot, | |
2689 | struct btrfs_extent_ref_v0); | |
2690 | *ref_objectid = btrfs_ref_objectid_v0(leaf, ref0); | |
2691 | break; | |
2692 | } | |
2693 | return 0; | |
2694 | } | |
2695 | #endif | |
2696 | ||
2697 | /* | |
2698 | * helper to add a tree block to the list. | |
2699 | * the major work is getting the generation and level of the block | |
2700 | */ | |
2701 | static int add_tree_block(struct reloc_control *rc, | |
2702 | struct btrfs_key *extent_key, | |
2703 | struct btrfs_path *path, | |
2704 | struct rb_root *blocks) | |
2705 | { | |
2706 | struct extent_buffer *eb; | |
2707 | struct btrfs_extent_item *ei; | |
2708 | struct btrfs_tree_block_info *bi; | |
2709 | struct tree_block *block; | |
2710 | struct rb_node *rb_node; | |
2711 | u32 item_size; | |
2712 | int level = -1; | |
2713 | int generation; | |
2714 | ||
2715 | eb = path->nodes[0]; | |
2716 | item_size = btrfs_item_size_nr(eb, path->slots[0]); | |
2717 | ||
2718 | if (item_size >= sizeof(*ei) + sizeof(*bi)) { | |
2719 | ei = btrfs_item_ptr(eb, path->slots[0], | |
2720 | struct btrfs_extent_item); | |
2721 | bi = (struct btrfs_tree_block_info *)(ei + 1); | |
2722 | generation = btrfs_extent_generation(eb, ei); | |
2723 | level = btrfs_tree_block_level(eb, bi); | |
2724 | } else { | |
2725 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
2726 | u64 ref_owner; | |
2727 | int ret; | |
2728 | ||
2729 | BUG_ON(item_size != sizeof(struct btrfs_extent_item_v0)); | |
2730 | ret = get_ref_objectid_v0(rc, path, extent_key, | |
2731 | &ref_owner, NULL); | |
2732 | BUG_ON(ref_owner >= BTRFS_MAX_LEVEL); | |
2733 | level = (int)ref_owner; | |
2734 | /* FIXME: get real generation */ | |
2735 | generation = 0; | |
2736 | #else | |
2737 | BUG(); | |
2738 | #endif | |
2739 | } | |
2740 | ||
2741 | btrfs_release_path(rc->extent_root, path); | |
2742 | ||
2743 | BUG_ON(level == -1); | |
2744 | ||
2745 | block = kmalloc(sizeof(*block), GFP_NOFS); | |
2746 | if (!block) | |
2747 | return -ENOMEM; | |
2748 | ||
2749 | block->bytenr = extent_key->objectid; | |
2750 | block->key.objectid = extent_key->offset; | |
2751 | block->key.offset = generation; | |
2752 | block->level = level; | |
2753 | block->key_ready = 0; | |
2754 | ||
2755 | rb_node = tree_insert(blocks, block->bytenr, &block->rb_node); | |
2756 | BUG_ON(rb_node); | |
2757 | ||
2758 | return 0; | |
2759 | } | |
2760 | ||
2761 | /* | |
2762 | * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY | |
2763 | */ | |
2764 | static int __add_tree_block(struct reloc_control *rc, | |
2765 | u64 bytenr, u32 blocksize, | |
2766 | struct rb_root *blocks) | |
2767 | { | |
2768 | struct btrfs_path *path; | |
2769 | struct btrfs_key key; | |
2770 | int ret; | |
2771 | ||
2772 | if (tree_block_processed(bytenr, blocksize, rc)) | |
2773 | return 0; | |
2774 | ||
2775 | if (tree_search(blocks, bytenr)) | |
2776 | return 0; | |
2777 | ||
2778 | path = btrfs_alloc_path(); | |
2779 | if (!path) | |
2780 | return -ENOMEM; | |
2781 | ||
2782 | key.objectid = bytenr; | |
2783 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
2784 | key.offset = blocksize; | |
2785 | ||
2786 | path->search_commit_root = 1; | |
2787 | path->skip_locking = 1; | |
2788 | ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 0, 0); | |
2789 | if (ret < 0) | |
2790 | goto out; | |
2791 | BUG_ON(ret); | |
2792 | ||
2793 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
2794 | ret = add_tree_block(rc, &key, path, blocks); | |
2795 | out: | |
2796 | btrfs_free_path(path); | |
2797 | return ret; | |
2798 | } | |
2799 | ||
2800 | /* | |
2801 | * helper to check if the block use full backrefs for pointers in it | |
2802 | */ | |
2803 | static int block_use_full_backref(struct reloc_control *rc, | |
2804 | struct extent_buffer *eb) | |
2805 | { | |
2806 | struct btrfs_path *path; | |
2807 | struct btrfs_extent_item *ei; | |
2808 | struct btrfs_key key; | |
2809 | u64 flags; | |
2810 | int ret; | |
2811 | ||
2812 | if (btrfs_header_flag(eb, BTRFS_HEADER_FLAG_RELOC) || | |
2813 | btrfs_header_backref_rev(eb) < BTRFS_MIXED_BACKREF_REV) | |
2814 | return 1; | |
2815 | ||
2816 | path = btrfs_alloc_path(); | |
2817 | BUG_ON(!path); | |
2818 | ||
2819 | key.objectid = eb->start; | |
2820 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
2821 | key.offset = eb->len; | |
2822 | ||
2823 | path->search_commit_root = 1; | |
2824 | path->skip_locking = 1; | |
2825 | ret = btrfs_search_slot(NULL, rc->extent_root, | |
2826 | &key, path, 0, 0); | |
2827 | BUG_ON(ret); | |
2828 | ||
2829 | ei = btrfs_item_ptr(path->nodes[0], path->slots[0], | |
2830 | struct btrfs_extent_item); | |
2831 | flags = btrfs_extent_flags(path->nodes[0], ei); | |
2832 | BUG_ON(!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)); | |
2833 | if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF) | |
2834 | ret = 1; | |
2835 | else | |
2836 | ret = 0; | |
2837 | btrfs_free_path(path); | |
2838 | return ret; | |
2839 | } | |
2840 | ||
2841 | /* | |
2842 | * helper to add tree blocks for backref of type BTRFS_EXTENT_DATA_REF_KEY | |
2843 | * this function scans fs tree to find blocks reference the data extent | |
2844 | */ | |
2845 | static int find_data_references(struct reloc_control *rc, | |
2846 | struct btrfs_key *extent_key, | |
2847 | struct extent_buffer *leaf, | |
2848 | struct btrfs_extent_data_ref *ref, | |
2849 | struct rb_root *blocks) | |
2850 | { | |
2851 | struct btrfs_path *path; | |
2852 | struct tree_block *block; | |
2853 | struct btrfs_root *root; | |
2854 | struct btrfs_file_extent_item *fi; | |
2855 | struct rb_node *rb_node; | |
2856 | struct btrfs_key key; | |
2857 | u64 ref_root; | |
2858 | u64 ref_objectid; | |
2859 | u64 ref_offset; | |
2860 | u32 ref_count; | |
2861 | u32 nritems; | |
2862 | int err = 0; | |
2863 | int added = 0; | |
2864 | int counted; | |
2865 | int ret; | |
2866 | ||
2867 | path = btrfs_alloc_path(); | |
2868 | if (!path) | |
2869 | return -ENOMEM; | |
2870 | ||
2871 | ref_root = btrfs_extent_data_ref_root(leaf, ref); | |
2872 | ref_objectid = btrfs_extent_data_ref_objectid(leaf, ref); | |
2873 | ref_offset = btrfs_extent_data_ref_offset(leaf, ref); | |
2874 | ref_count = btrfs_extent_data_ref_count(leaf, ref); | |
2875 | ||
2876 | root = read_fs_root(rc->extent_root->fs_info, ref_root); | |
2877 | if (IS_ERR(root)) { | |
2878 | err = PTR_ERR(root); | |
2879 | goto out; | |
2880 | } | |
2881 | ||
2882 | key.objectid = ref_objectid; | |
2883 | key.offset = ref_offset; | |
2884 | key.type = BTRFS_EXTENT_DATA_KEY; | |
2885 | ||
2886 | path->search_commit_root = 1; | |
2887 | path->skip_locking = 1; | |
2888 | ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); | |
2889 | if (ret < 0) { | |
2890 | err = ret; | |
2891 | goto out; | |
2892 | } | |
2893 | ||
2894 | leaf = path->nodes[0]; | |
2895 | nritems = btrfs_header_nritems(leaf); | |
2896 | /* | |
2897 | * the references in tree blocks that use full backrefs | |
2898 | * are not counted in | |
2899 | */ | |
2900 | if (block_use_full_backref(rc, leaf)) | |
2901 | counted = 0; | |
2902 | else | |
2903 | counted = 1; | |
2904 | rb_node = tree_search(blocks, leaf->start); | |
2905 | if (rb_node) { | |
2906 | if (counted) | |
2907 | added = 1; | |
2908 | else | |
2909 | path->slots[0] = nritems; | |
2910 | } | |
2911 | ||
2912 | while (ref_count > 0) { | |
2913 | while (path->slots[0] >= nritems) { | |
2914 | ret = btrfs_next_leaf(root, path); | |
2915 | if (ret < 0) { | |
2916 | err = ret; | |
2917 | goto out; | |
2918 | } | |
2919 | if (ret > 0) { | |
2920 | WARN_ON(1); | |
2921 | goto out; | |
2922 | } | |
2923 | ||
2924 | leaf = path->nodes[0]; | |
2925 | nritems = btrfs_header_nritems(leaf); | |
2926 | added = 0; | |
2927 | ||
2928 | if (block_use_full_backref(rc, leaf)) | |
2929 | counted = 0; | |
2930 | else | |
2931 | counted = 1; | |
2932 | rb_node = tree_search(blocks, leaf->start); | |
2933 | if (rb_node) { | |
2934 | if (counted) | |
2935 | added = 1; | |
2936 | else | |
2937 | path->slots[0] = nritems; | |
2938 | } | |
2939 | } | |
2940 | ||
2941 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
2942 | if (key.objectid != ref_objectid || | |
2943 | key.type != BTRFS_EXTENT_DATA_KEY) { | |
2944 | WARN_ON(1); | |
2945 | break; | |
2946 | } | |
2947 | ||
2948 | fi = btrfs_item_ptr(leaf, path->slots[0], | |
2949 | struct btrfs_file_extent_item); | |
2950 | ||
2951 | if (btrfs_file_extent_type(leaf, fi) == | |
2952 | BTRFS_FILE_EXTENT_INLINE) | |
2953 | goto next; | |
2954 | ||
2955 | if (btrfs_file_extent_disk_bytenr(leaf, fi) != | |
2956 | extent_key->objectid) | |
2957 | goto next; | |
2958 | ||
2959 | key.offset -= btrfs_file_extent_offset(leaf, fi); | |
2960 | if (key.offset != ref_offset) | |
2961 | goto next; | |
2962 | ||
2963 | if (counted) | |
2964 | ref_count--; | |
2965 | if (added) | |
2966 | goto next; | |
2967 | ||
2968 | if (!tree_block_processed(leaf->start, leaf->len, rc)) { | |
2969 | block = kmalloc(sizeof(*block), GFP_NOFS); | |
2970 | if (!block) { | |
2971 | err = -ENOMEM; | |
2972 | break; | |
2973 | } | |
2974 | block->bytenr = leaf->start; | |
2975 | btrfs_item_key_to_cpu(leaf, &block->key, 0); | |
2976 | block->level = 0; | |
2977 | block->key_ready = 1; | |
2978 | rb_node = tree_insert(blocks, block->bytenr, | |
2979 | &block->rb_node); | |
2980 | BUG_ON(rb_node); | |
2981 | } | |
2982 | if (counted) | |
2983 | added = 1; | |
2984 | else | |
2985 | path->slots[0] = nritems; | |
2986 | next: | |
2987 | path->slots[0]++; | |
2988 | ||
2989 | } | |
2990 | out: | |
2991 | btrfs_free_path(path); | |
2992 | return err; | |
2993 | } | |
2994 | ||
2995 | /* | |
2996 | * hepler to find all tree blocks that reference a given data extent | |
2997 | */ | |
2998 | static noinline_for_stack | |
2999 | int add_data_references(struct reloc_control *rc, | |
3000 | struct btrfs_key *extent_key, | |
3001 | struct btrfs_path *path, | |
3002 | struct rb_root *blocks) | |
3003 | { | |
3004 | struct btrfs_key key; | |
3005 | struct extent_buffer *eb; | |
3006 | struct btrfs_extent_data_ref *dref; | |
3007 | struct btrfs_extent_inline_ref *iref; | |
3008 | unsigned long ptr; | |
3009 | unsigned long end; | |
3010 | u32 blocksize; | |
3011 | int ret; | |
3012 | int err = 0; | |
3013 | ||
3014 | ret = get_new_location(rc->data_inode, NULL, extent_key->objectid, | |
3015 | extent_key->offset); | |
3016 | BUG_ON(ret < 0); | |
3017 | if (ret > 0) { | |
3018 | /* the relocated data is fragmented */ | |
3019 | rc->extents_skipped++; | |
3020 | btrfs_release_path(rc->extent_root, path); | |
3021 | return 0; | |
3022 | } | |
3023 | ||
3024 | blocksize = btrfs_level_size(rc->extent_root, 0); | |
3025 | ||
3026 | eb = path->nodes[0]; | |
3027 | ptr = btrfs_item_ptr_offset(eb, path->slots[0]); | |
3028 | end = ptr + btrfs_item_size_nr(eb, path->slots[0]); | |
3029 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
3030 | if (ptr + sizeof(struct btrfs_extent_item_v0) == end) | |
3031 | ptr = end; | |
3032 | else | |
3033 | #endif | |
3034 | ptr += sizeof(struct btrfs_extent_item); | |
3035 | ||
3036 | while (ptr < end) { | |
3037 | iref = (struct btrfs_extent_inline_ref *)ptr; | |
3038 | key.type = btrfs_extent_inline_ref_type(eb, iref); | |
3039 | if (key.type == BTRFS_SHARED_DATA_REF_KEY) { | |
3040 | key.offset = btrfs_extent_inline_ref_offset(eb, iref); | |
3041 | ret = __add_tree_block(rc, key.offset, blocksize, | |
3042 | blocks); | |
3043 | } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { | |
3044 | dref = (struct btrfs_extent_data_ref *)(&iref->offset); | |
3045 | ret = find_data_references(rc, extent_key, | |
3046 | eb, dref, blocks); | |
3047 | } else { | |
3048 | BUG(); | |
3049 | } | |
3050 | ptr += btrfs_extent_inline_ref_size(key.type); | |
3051 | } | |
3052 | WARN_ON(ptr > end); | |
3053 | ||
3054 | while (1) { | |
3055 | cond_resched(); | |
3056 | eb = path->nodes[0]; | |
3057 | if (path->slots[0] >= btrfs_header_nritems(eb)) { | |
3058 | ret = btrfs_next_leaf(rc->extent_root, path); | |
3059 | if (ret < 0) { | |
3060 | err = ret; | |
3061 | break; | |
3062 | } | |
3063 | if (ret > 0) | |
3064 | break; | |
3065 | eb = path->nodes[0]; | |
3066 | } | |
3067 | ||
3068 | btrfs_item_key_to_cpu(eb, &key, path->slots[0]); | |
3069 | if (key.objectid != extent_key->objectid) | |
3070 | break; | |
3071 | ||
3072 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
3073 | if (key.type == BTRFS_SHARED_DATA_REF_KEY || | |
3074 | key.type == BTRFS_EXTENT_REF_V0_KEY) { | |
3075 | #else | |
3076 | BUG_ON(key.type == BTRFS_EXTENT_REF_V0_KEY); | |
3077 | if (key.type == BTRFS_SHARED_DATA_REF_KEY) { | |
3078 | #endif | |
3079 | ret = __add_tree_block(rc, key.offset, blocksize, | |
3080 | blocks); | |
3081 | } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) { | |
3082 | dref = btrfs_item_ptr(eb, path->slots[0], | |
3083 | struct btrfs_extent_data_ref); | |
3084 | ret = find_data_references(rc, extent_key, | |
3085 | eb, dref, blocks); | |
3086 | } else { | |
3087 | ret = 0; | |
3088 | } | |
3089 | if (ret) { | |
3090 | err = ret; | |
3091 | break; | |
3092 | } | |
3093 | path->slots[0]++; | |
3094 | } | |
3095 | btrfs_release_path(rc->extent_root, path); | |
3096 | if (err) | |
3097 | free_block_list(blocks); | |
3098 | return err; | |
3099 | } | |
3100 | ||
3101 | /* | |
3102 | * hepler to find next unprocessed extent | |
3103 | */ | |
3104 | static noinline_for_stack | |
3105 | int find_next_extent(struct btrfs_trans_handle *trans, | |
3106 | struct reloc_control *rc, struct btrfs_path *path) | |
3107 | { | |
3108 | struct btrfs_key key; | |
3109 | struct extent_buffer *leaf; | |
3110 | u64 start, end, last; | |
3111 | int ret; | |
3112 | ||
3113 | last = rc->block_group->key.objectid + rc->block_group->key.offset; | |
3114 | while (1) { | |
3115 | cond_resched(); | |
3116 | if (rc->search_start >= last) { | |
3117 | ret = 1; | |
3118 | break; | |
3119 | } | |
3120 | ||
3121 | key.objectid = rc->search_start; | |
3122 | key.type = BTRFS_EXTENT_ITEM_KEY; | |
3123 | key.offset = 0; | |
3124 | ||
3125 | path->search_commit_root = 1; | |
3126 | path->skip_locking = 1; | |
3127 | ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, | |
3128 | 0, 0); | |
3129 | if (ret < 0) | |
3130 | break; | |
3131 | next: | |
3132 | leaf = path->nodes[0]; | |
3133 | if (path->slots[0] >= btrfs_header_nritems(leaf)) { | |
3134 | ret = btrfs_next_leaf(rc->extent_root, path); | |
3135 | if (ret != 0) | |
3136 | break; | |
3137 | leaf = path->nodes[0]; | |
3138 | } | |
3139 | ||
3140 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
3141 | if (key.objectid >= last) { | |
3142 | ret = 1; | |
3143 | break; | |
3144 | } | |
3145 | ||
3146 | if (key.type != BTRFS_EXTENT_ITEM_KEY || | |
3147 | key.objectid + key.offset <= rc->search_start) { | |
3148 | path->slots[0]++; | |
3149 | goto next; | |
3150 | } | |
3151 | ||
3152 | ret = find_first_extent_bit(&rc->processed_blocks, | |
3153 | key.objectid, &start, &end, | |
3154 | EXTENT_DIRTY); | |
3155 | ||
3156 | if (ret == 0 && start <= key.objectid) { | |
3157 | btrfs_release_path(rc->extent_root, path); | |
3158 | rc->search_start = end + 1; | |
3159 | } else { | |
3160 | rc->search_start = key.objectid + key.offset; | |
3161 | return 0; | |
3162 | } | |
3163 | } | |
3164 | btrfs_release_path(rc->extent_root, path); | |
3165 | return ret; | |
3166 | } | |
3167 | ||
3168 | static void set_reloc_control(struct reloc_control *rc) | |
3169 | { | |
3170 | struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; | |
3171 | mutex_lock(&fs_info->trans_mutex); | |
3172 | fs_info->reloc_ctl = rc; | |
3173 | mutex_unlock(&fs_info->trans_mutex); | |
3174 | } | |
3175 | ||
3176 | static void unset_reloc_control(struct reloc_control *rc) | |
3177 | { | |
3178 | struct btrfs_fs_info *fs_info = rc->extent_root->fs_info; | |
3179 | mutex_lock(&fs_info->trans_mutex); | |
3180 | fs_info->reloc_ctl = NULL; | |
3181 | mutex_unlock(&fs_info->trans_mutex); | |
3182 | } | |
3183 | ||
3184 | static int check_extent_flags(u64 flags) | |
3185 | { | |
3186 | if ((flags & BTRFS_EXTENT_FLAG_DATA) && | |
3187 | (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) | |
3188 | return 1; | |
3189 | if (!(flags & BTRFS_EXTENT_FLAG_DATA) && | |
3190 | !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK)) | |
3191 | return 1; | |
3192 | if ((flags & BTRFS_EXTENT_FLAG_DATA) && | |
3193 | (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)) | |
3194 | return 1; | |
3195 | return 0; | |
3196 | } | |
3197 | ||
3198 | static noinline_for_stack int relocate_block_group(struct reloc_control *rc) | |
3199 | { | |
3200 | struct rb_root blocks = RB_ROOT; | |
3201 | struct btrfs_key key; | |
3202 | struct btrfs_trans_handle *trans = NULL; | |
3203 | struct btrfs_path *path; | |
3204 | struct btrfs_extent_item *ei; | |
3205 | unsigned long nr; | |
3206 | u64 flags; | |
3207 | u32 item_size; | |
3208 | int ret; | |
3209 | int err = 0; | |
3210 | ||
3211 | path = btrfs_alloc_path(); | |
3212 | if (!path) | |
3213 | return -ENOMEM; | |
3214 | ||
3215 | rc->search_start = rc->block_group->key.objectid; | |
3216 | clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY, | |
3217 | GFP_NOFS); | |
3218 | ||
3219 | rc->create_reloc_root = 1; | |
3220 | set_reloc_control(rc); | |
3221 | ||
3222 | trans = btrfs_start_transaction(rc->extent_root, 1); | |
3223 | btrfs_commit_transaction(trans, rc->extent_root); | |
3224 | ||
3225 | while (1) { | |
3226 | trans = btrfs_start_transaction(rc->extent_root, 1); | |
3227 | ||
3228 | ret = find_next_extent(trans, rc, path); | |
3229 | if (ret < 0) | |
3230 | err = ret; | |
3231 | if (ret != 0) | |
3232 | break; | |
3233 | ||
3234 | rc->extents_found++; | |
3235 | ||
3236 | ei = btrfs_item_ptr(path->nodes[0], path->slots[0], | |
3237 | struct btrfs_extent_item); | |
3238 | btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); | |
3239 | item_size = btrfs_item_size_nr(path->nodes[0], | |
3240 | path->slots[0]); | |
3241 | if (item_size >= sizeof(*ei)) { | |
3242 | flags = btrfs_extent_flags(path->nodes[0], ei); | |
3243 | ret = check_extent_flags(flags); | |
3244 | BUG_ON(ret); | |
3245 | ||
3246 | } else { | |
3247 | #ifdef BTRFS_COMPAT_EXTENT_TREE_V0 | |
3248 | u64 ref_owner; | |
3249 | int path_change = 0; | |
3250 | ||
3251 | BUG_ON(item_size != | |
3252 | sizeof(struct btrfs_extent_item_v0)); | |
3253 | ret = get_ref_objectid_v0(rc, path, &key, &ref_owner, | |
3254 | &path_change); | |
3255 | if (ref_owner < BTRFS_FIRST_FREE_OBJECTID) | |
3256 | flags = BTRFS_EXTENT_FLAG_TREE_BLOCK; | |
3257 | else | |
3258 | flags = BTRFS_EXTENT_FLAG_DATA; | |
3259 | ||
3260 | if (path_change) { | |
3261 | btrfs_release_path(rc->extent_root, path); | |
3262 | ||
3263 | path->search_commit_root = 1; | |
3264 | path->skip_locking = 1; | |
3265 | ret = btrfs_search_slot(NULL, rc->extent_root, | |
3266 | &key, path, 0, 0); | |
3267 | if (ret < 0) { | |
3268 | err = ret; | |
3269 | break; | |
3270 | } | |
3271 | BUG_ON(ret > 0); | |
3272 | } | |
3273 | #else | |
3274 | BUG(); | |
3275 | #endif | |
3276 | } | |
3277 | ||
3278 | if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) { | |
3279 | ret = add_tree_block(rc, &key, path, &blocks); | |
3280 | } else if (rc->stage == UPDATE_DATA_PTRS && | |
3281 | (flags & BTRFS_EXTENT_FLAG_DATA)) { | |
3282 | ret = add_data_references(rc, &key, path, &blocks); | |
3283 | } else { | |
3284 | btrfs_release_path(rc->extent_root, path); | |
3285 | ret = 0; | |
3286 | } | |
3287 | if (ret < 0) { | |
3288 | err = 0; | |
3289 | break; | |
3290 | } | |
3291 | ||
3292 | if (!RB_EMPTY_ROOT(&blocks)) { | |
3293 | ret = relocate_tree_blocks(trans, rc, &blocks); | |
3294 | if (ret < 0) { | |
3295 | err = ret; | |
3296 | break; | |
3297 | } | |
3298 | } | |
3299 | ||
3300 | nr = trans->blocks_used; | |
3301 | btrfs_end_transaction_throttle(trans, rc->extent_root); | |
3302 | trans = NULL; | |
3303 | btrfs_btree_balance_dirty(rc->extent_root, nr); | |
3304 | ||
3305 | if (rc->stage == MOVE_DATA_EXTENTS && | |
3306 | (flags & BTRFS_EXTENT_FLAG_DATA)) { | |
3307 | rc->found_file_extent = 1; | |
3308 | ret = relocate_data_extent(rc->data_inode, &key); | |
3309 | if (ret < 0) { | |
3310 | err = ret; | |
3311 | break; | |
3312 | } | |
3313 | } | |
3314 | } | |
3315 | btrfs_free_path(path); | |
3316 | ||
3317 | if (trans) { | |
3318 | nr = trans->blocks_used; | |
3319 | btrfs_end_transaction(trans, rc->extent_root); | |
3320 | btrfs_btree_balance_dirty(rc->extent_root, nr); | |
3321 | } | |
3322 | ||
3323 | rc->create_reloc_root = 0; | |
3324 | smp_mb(); | |
3325 | ||
3326 | if (rc->extents_found > 0) { | |
3327 | trans = btrfs_start_transaction(rc->extent_root, 1); | |
3328 | btrfs_commit_transaction(trans, rc->extent_root); | |
3329 | } | |
3330 | ||
3331 | merge_reloc_roots(rc); | |
3332 | ||
3333 | unset_reloc_control(rc); | |
3334 | ||
3335 | /* get rid of pinned extents */ | |
3336 | trans = btrfs_start_transaction(rc->extent_root, 1); | |
3337 | btrfs_commit_transaction(trans, rc->extent_root); | |
3338 | ||
3339 | return err; | |
3340 | } | |
3341 | ||
3342 | static int __insert_orphan_inode(struct btrfs_trans_handle *trans, | |
3343 | struct btrfs_root *root, | |
3344 | u64 objectid, u64 size) | |
3345 | { | |
3346 | struct btrfs_path *path; | |
3347 | struct btrfs_inode_item *item; | |
3348 | struct extent_buffer *leaf; | |
3349 | int ret; | |
3350 | ||
3351 | path = btrfs_alloc_path(); | |
3352 | if (!path) | |
3353 | return -ENOMEM; | |
3354 | ||
3355 | ret = btrfs_insert_empty_inode(trans, root, path, objectid); | |
3356 | if (ret) | |
3357 | goto out; | |
3358 | ||
3359 | leaf = path->nodes[0]; | |
3360 | item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item); | |
3361 | memset_extent_buffer(leaf, 0, (unsigned long)item, sizeof(*item)); | |
3362 | btrfs_set_inode_generation(leaf, item, 1); | |
3363 | btrfs_set_inode_size(leaf, item, size); | |
3364 | btrfs_set_inode_mode(leaf, item, S_IFREG | 0600); | |
3365 | btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS); | |
3366 | btrfs_mark_buffer_dirty(leaf); | |
3367 | btrfs_release_path(root, path); | |
3368 | out: | |
3369 | btrfs_free_path(path); | |
3370 | return ret; | |
3371 | } | |
3372 | ||
3373 | /* | |
3374 | * helper to create inode for data relocation. | |
3375 | * the inode is in data relocation tree and its link count is 0 | |
3376 | */ | |
3377 | static struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info, | |
3378 | struct btrfs_block_group_cache *group) | |
3379 | { | |
3380 | struct inode *inode = NULL; | |
3381 | struct btrfs_trans_handle *trans; | |
3382 | struct btrfs_root *root; | |
3383 | struct btrfs_key key; | |
3384 | unsigned long nr; | |
3385 | u64 objectid = BTRFS_FIRST_FREE_OBJECTID; | |
3386 | int err = 0; | |
3387 | ||
3388 | root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID); | |
3389 | if (IS_ERR(root)) | |
3390 | return ERR_CAST(root); | |
3391 | ||
3392 | trans = btrfs_start_transaction(root, 1); | |
3393 | BUG_ON(!trans); | |
3394 | ||
3395 | err = btrfs_find_free_objectid(trans, root, objectid, &objectid); | |
3396 | if (err) | |
3397 | goto out; | |
3398 | ||
3399 | err = __insert_orphan_inode(trans, root, objectid, group->key.offset); | |
3400 | BUG_ON(err); | |
3401 | ||
3402 | err = btrfs_insert_file_extent(trans, root, objectid, 0, 0, 0, | |
3403 | group->key.offset, 0, group->key.offset, | |
3404 | 0, 0, 0); | |
3405 | BUG_ON(err); | |
3406 | ||
3407 | key.objectid = objectid; | |
3408 | key.type = BTRFS_INODE_ITEM_KEY; | |
3409 | key.offset = 0; | |
3410 | inode = btrfs_iget(root->fs_info->sb, &key, root); | |
3411 | BUG_ON(IS_ERR(inode) || is_bad_inode(inode)); | |
3412 | BTRFS_I(inode)->index_cnt = group->key.objectid; | |
3413 | ||
3414 | err = btrfs_orphan_add(trans, inode); | |
3415 | out: | |
3416 | nr = trans->blocks_used; | |
3417 | btrfs_end_transaction(trans, root); | |
3418 | ||
3419 | btrfs_btree_balance_dirty(root, nr); | |
3420 | if (err) { | |
3421 | if (inode) | |
3422 | iput(inode); | |
3423 | inode = ERR_PTR(err); | |
3424 | } | |
3425 | return inode; | |
3426 | } | |
3427 | ||
3428 | /* | |
3429 | * function to relocate all extents in a block group. | |
3430 | */ | |
3431 | int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start) | |
3432 | { | |
3433 | struct btrfs_fs_info *fs_info = extent_root->fs_info; | |
3434 | struct reloc_control *rc; | |
3435 | int ret; | |
3436 | int err = 0; | |
3437 | ||
3438 | rc = kzalloc(sizeof(*rc), GFP_NOFS); | |
3439 | if (!rc) | |
3440 | return -ENOMEM; | |
3441 | ||
3442 | mapping_tree_init(&rc->reloc_root_tree); | |
3443 | extent_io_tree_init(&rc->processed_blocks, NULL, GFP_NOFS); | |
3444 | INIT_LIST_HEAD(&rc->reloc_roots); | |
3445 | ||
3446 | rc->block_group = btrfs_lookup_block_group(fs_info, group_start); | |
3447 | BUG_ON(!rc->block_group); | |
3448 | ||
3449 | btrfs_init_workers(&rc->workers, "relocate", | |
3450 | fs_info->thread_pool_size); | |
3451 | ||
3452 | rc->extent_root = extent_root; | |
3453 | btrfs_prepare_block_group_relocation(extent_root, rc->block_group); | |
3454 | ||
3455 | rc->data_inode = create_reloc_inode(fs_info, rc->block_group); | |
3456 | if (IS_ERR(rc->data_inode)) { | |
3457 | err = PTR_ERR(rc->data_inode); | |
3458 | rc->data_inode = NULL; | |
3459 | goto out; | |
3460 | } | |
3461 | ||
3462 | printk(KERN_INFO "btrfs: relocating block group %llu flags %llu\n", | |
3463 | (unsigned long long)rc->block_group->key.objectid, | |
3464 | (unsigned long long)rc->block_group->flags); | |
3465 | ||
3466 | btrfs_start_delalloc_inodes(fs_info->tree_root); | |
3467 | btrfs_wait_ordered_extents(fs_info->tree_root, 0); | |
3468 | ||
3469 | while (1) { | |
3470 | mutex_lock(&fs_info->cleaner_mutex); | |
3471 | btrfs_clean_old_snapshots(fs_info->tree_root); | |
3472 | mutex_unlock(&fs_info->cleaner_mutex); | |
3473 | ||
3474 | rc->extents_found = 0; | |
3475 | rc->extents_skipped = 0; | |
3476 | ||
3477 | ret = relocate_block_group(rc); | |
3478 | if (ret < 0) { | |
3479 | err = ret; | |
3480 | break; | |
3481 | } | |
3482 | ||
3483 | if (rc->extents_found == 0) | |
3484 | break; | |
3485 | ||
3486 | printk(KERN_INFO "btrfs: found %llu extents\n", | |
3487 | (unsigned long long)rc->extents_found); | |
3488 | ||
3489 | if (rc->stage == MOVE_DATA_EXTENTS && rc->found_file_extent) { | |
3490 | btrfs_wait_ordered_range(rc->data_inode, 0, (u64)-1); | |
3491 | invalidate_mapping_pages(rc->data_inode->i_mapping, | |
3492 | 0, -1); | |
3493 | rc->stage = UPDATE_DATA_PTRS; | |
3494 | } else if (rc->stage == UPDATE_DATA_PTRS && | |
3495 | rc->extents_skipped >= rc->extents_found) { | |
3496 | iput(rc->data_inode); | |
3497 | rc->data_inode = create_reloc_inode(fs_info, | |
3498 | rc->block_group); | |
3499 | if (IS_ERR(rc->data_inode)) { | |
3500 | err = PTR_ERR(rc->data_inode); | |
3501 | rc->data_inode = NULL; | |
3502 | break; | |
3503 | } | |
3504 | rc->stage = MOVE_DATA_EXTENTS; | |
3505 | rc->found_file_extent = 0; | |
3506 | } | |
3507 | } | |
3508 | ||
3509 | filemap_fdatawrite_range(fs_info->btree_inode->i_mapping, | |
3510 | rc->block_group->key.objectid, | |
3511 | rc->block_group->key.objectid + | |
3512 | rc->block_group->key.offset - 1); | |
3513 | ||
3514 | WARN_ON(rc->block_group->pinned > 0); | |
3515 | WARN_ON(rc->block_group->reserved > 0); | |
3516 | WARN_ON(btrfs_block_group_used(&rc->block_group->item) > 0); | |
3517 | out: | |
3518 | iput(rc->data_inode); | |
3519 | btrfs_stop_workers(&rc->workers); | |
3520 | btrfs_put_block_group(rc->block_group); | |
3521 | kfree(rc); | |
3522 | return err; | |
3523 | } | |
3524 | ||
3525 | /* | |
3526 | * recover relocation interrupted by system crash. | |
3527 | * | |
3528 | * this function resumes merging reloc trees with corresponding fs trees. | |
3529 | * this is important for keeping the sharing of tree blocks | |
3530 | */ | |
3531 | int btrfs_recover_relocation(struct btrfs_root *root) | |
3532 | { | |
3533 | LIST_HEAD(reloc_roots); | |
3534 | struct btrfs_key key; | |
3535 | struct btrfs_root *fs_root; | |
3536 | struct btrfs_root *reloc_root; | |
3537 | struct btrfs_path *path; | |
3538 | struct extent_buffer *leaf; | |
3539 | struct reloc_control *rc = NULL; | |
3540 | struct btrfs_trans_handle *trans; | |
3541 | int ret; | |
3542 | int err = 0; | |
3543 | ||
3544 | path = btrfs_alloc_path(); | |
3545 | if (!path) | |
3546 | return -ENOMEM; | |
3547 | ||
3548 | key.objectid = BTRFS_TREE_RELOC_OBJECTID; | |
3549 | key.type = BTRFS_ROOT_ITEM_KEY; | |
3550 | key.offset = (u64)-1; | |
3551 | ||
3552 | while (1) { | |
3553 | ret = btrfs_search_slot(NULL, root->fs_info->tree_root, &key, | |
3554 | path, 0, 0); | |
3555 | if (ret < 0) { | |
3556 | err = ret; | |
3557 | goto out; | |
3558 | } | |
3559 | if (ret > 0) { | |
3560 | if (path->slots[0] == 0) | |
3561 | break; | |
3562 | path->slots[0]--; | |
3563 | } | |
3564 | leaf = path->nodes[0]; | |
3565 | btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); | |
3566 | btrfs_release_path(root->fs_info->tree_root, path); | |
3567 | ||
3568 | if (key.objectid != BTRFS_TREE_RELOC_OBJECTID || | |
3569 | key.type != BTRFS_ROOT_ITEM_KEY) | |
3570 | break; | |
3571 | ||
3572 | reloc_root = btrfs_read_fs_root_no_radix(root, &key); | |
3573 | if (IS_ERR(reloc_root)) { | |
3574 | err = PTR_ERR(reloc_root); | |
3575 | goto out; | |
3576 | } | |
3577 | ||
3578 | list_add(&reloc_root->root_list, &reloc_roots); | |
3579 | ||
3580 | if (btrfs_root_refs(&reloc_root->root_item) > 0) { | |
3581 | fs_root = read_fs_root(root->fs_info, | |
3582 | reloc_root->root_key.offset); | |
3583 | if (IS_ERR(fs_root)) { | |
3584 | err = PTR_ERR(fs_root); | |
3585 | goto out; | |
3586 | } | |
3587 | } | |
3588 | ||
3589 | if (key.offset == 0) | |
3590 | break; | |
3591 | ||
3592 | key.offset--; | |
3593 | } | |
3594 | btrfs_release_path(root->fs_info->tree_root, path); | |
3595 | ||
3596 | if (list_empty(&reloc_roots)) | |
3597 | goto out; | |
3598 | ||
3599 | rc = kzalloc(sizeof(*rc), GFP_NOFS); | |
3600 | if (!rc) { | |
3601 | err = -ENOMEM; | |
3602 | goto out; | |
3603 | } | |
3604 | ||
3605 | mapping_tree_init(&rc->reloc_root_tree); | |
3606 | INIT_LIST_HEAD(&rc->reloc_roots); | |
3607 | btrfs_init_workers(&rc->workers, "relocate", | |
3608 | root->fs_info->thread_pool_size); | |
3609 | rc->extent_root = root->fs_info->extent_root; | |
3610 | ||
3611 | set_reloc_control(rc); | |
3612 | ||
3613 | while (!list_empty(&reloc_roots)) { | |
3614 | reloc_root = list_entry(reloc_roots.next, | |
3615 | struct btrfs_root, root_list); | |
3616 | list_del(&reloc_root->root_list); | |
3617 | ||
3618 | if (btrfs_root_refs(&reloc_root->root_item) == 0) { | |
3619 | list_add_tail(&reloc_root->root_list, | |
3620 | &rc->reloc_roots); | |
3621 | continue; | |
3622 | } | |
3623 | ||
3624 | fs_root = read_fs_root(root->fs_info, | |
3625 | reloc_root->root_key.offset); | |
3626 | BUG_ON(IS_ERR(fs_root)); | |
3627 | ||
3628 | __add_reloc_root(reloc_root); | |
3629 | fs_root->reloc_root = reloc_root; | |
3630 | } | |
3631 | ||
3632 | trans = btrfs_start_transaction(rc->extent_root, 1); | |
3633 | btrfs_commit_transaction(trans, rc->extent_root); | |
3634 | ||
3635 | merge_reloc_roots(rc); | |
3636 | ||
3637 | unset_reloc_control(rc); | |
3638 | ||
3639 | trans = btrfs_start_transaction(rc->extent_root, 1); | |
3640 | btrfs_commit_transaction(trans, rc->extent_root); | |
3641 | out: | |
3642 | if (rc) { | |
3643 | btrfs_stop_workers(&rc->workers); | |
3644 | kfree(rc); | |
3645 | } | |
3646 | while (!list_empty(&reloc_roots)) { | |
3647 | reloc_root = list_entry(reloc_roots.next, | |
3648 | struct btrfs_root, root_list); | |
3649 | list_del(&reloc_root->root_list); | |
3650 | free_extent_buffer(reloc_root->node); | |
3651 | free_extent_buffer(reloc_root->commit_root); | |
3652 | kfree(reloc_root); | |
3653 | } | |
3654 | btrfs_free_path(path); | |
3655 | ||
3656 | if (err == 0) { | |
3657 | /* cleanup orphan inode in data relocation tree */ | |
3658 | fs_root = read_fs_root(root->fs_info, | |
3659 | BTRFS_DATA_RELOC_TREE_OBJECTID); | |
3660 | if (IS_ERR(fs_root)) | |
3661 | err = PTR_ERR(fs_root); | |
3662 | } | |
3663 | return err; | |
3664 | } | |
3665 | ||
3666 | /* | |
3667 | * helper to add ordered checksum for data relocation. | |
3668 | * | |
3669 | * cloning checksum properly handles the nodatasum extents. | |
3670 | * it also saves CPU time to re-calculate the checksum. | |
3671 | */ | |
3672 | int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len) | |
3673 | { | |
3674 | struct btrfs_ordered_sum *sums; | |
3675 | struct btrfs_sector_sum *sector_sum; | |
3676 | struct btrfs_ordered_extent *ordered; | |
3677 | struct btrfs_root *root = BTRFS_I(inode)->root; | |
3678 | size_t offset; | |
3679 | int ret; | |
3680 | u64 disk_bytenr; | |
3681 | LIST_HEAD(list); | |
3682 | ||
3683 | ordered = btrfs_lookup_ordered_extent(inode, file_pos); | |
3684 | BUG_ON(ordered->file_offset != file_pos || ordered->len != len); | |
3685 | ||
3686 | disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt; | |
3687 | ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr, | |
3688 | disk_bytenr + len - 1, &list); | |
3689 | ||
3690 | while (!list_empty(&list)) { | |
3691 | sums = list_entry(list.next, struct btrfs_ordered_sum, list); | |
3692 | list_del_init(&sums->list); | |
3693 | ||
3694 | sector_sum = sums->sums; | |
3695 | sums->bytenr = ordered->start; | |
3696 | ||
3697 | offset = 0; | |
3698 | while (offset < sums->len) { | |
3699 | sector_sum->bytenr += ordered->start - disk_bytenr; | |
3700 | sector_sum++; | |
3701 | offset += root->sectorsize; | |
3702 | } | |
3703 | ||
3704 | btrfs_add_ordered_sum(inode, ordered, sums); | |
3705 | } | |
3706 | btrfs_put_ordered_extent(ordered); | |
3707 | return 0; | |
3708 | } |