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5
6#include <linux/sched.h>
7#include <linux/pagemap.h>
8#include <linux/writeback.h>
9#include <linux/blkdev.h>
10#include <linux/rbtree.h>
11#include <linux/slab.h>
12#include "ctree.h"
13#include "disk-io.h"
14#include "transaction.h"
15#include "volumes.h"
16#include "locking.h"
17#include "btrfs_inode.h"
18#include "async-thread.h"
19#include "free-space-cache.h"
20#include "inode-map.h"
21#include "qgroup.h"
22#include "print-tree.h"
23#include "delalloc-space.h"
24
25
26
27
28struct tree_entry {
29 struct rb_node rb_node;
30 u64 bytenr;
31};
32
33
34
35
36struct backref_node {
37 struct rb_node rb_node;
38 u64 bytenr;
39
40 u64 new_bytenr;
41
42 u64 owner;
43
44 struct list_head list;
45
46 struct list_head upper;
47
48 struct list_head lower;
49
50 struct btrfs_root *root;
51
52 struct extent_buffer *eb;
53
54 unsigned int level:8;
55
56 unsigned int cowonly:1;
57
58 unsigned int lowest:1;
59
60 unsigned int locked:1;
61
62 unsigned int processed:1;
63
64 unsigned int checked:1;
65
66
67
68
69 unsigned int pending:1;
70
71
72
73
74 unsigned int detached:1;
75};
76
77
78
79
80struct backref_edge {
81 struct list_head list[2];
82 struct backref_node *node[2];
83};
84
85#define LOWER 0
86#define UPPER 1
87#define RELOCATION_RESERVED_NODES 256
88
89struct backref_cache {
90
91 struct rb_root rb_root;
92
93 struct backref_node *path[BTRFS_MAX_LEVEL];
94
95
96
97
98
99 struct list_head pending[BTRFS_MAX_LEVEL];
100
101 struct list_head leaves;
102
103 struct list_head changed;
104
105 struct list_head detached;
106
107 u64 last_trans;
108
109 int nr_nodes;
110 int nr_edges;
111};
112
113
114
115
116struct mapping_node {
117 struct rb_node rb_node;
118 u64 bytenr;
119 void *data;
120};
121
122struct mapping_tree {
123 struct rb_root rb_root;
124 spinlock_t lock;
125};
126
127
128
129
130struct tree_block {
131 struct rb_node rb_node;
132 u64 bytenr;
133 struct btrfs_key key;
134 unsigned int level:8;
135 unsigned int key_ready:1;
136};
137
138#define MAX_EXTENTS 128
139
140struct file_extent_cluster {
141 u64 start;
142 u64 end;
143 u64 boundary[MAX_EXTENTS];
144 unsigned int nr;
145};
146
147struct reloc_control {
148
149 struct btrfs_block_group_cache *block_group;
150
151 struct btrfs_root *extent_root;
152
153 struct inode *data_inode;
154
155 struct btrfs_block_rsv *block_rsv;
156
157 struct backref_cache backref_cache;
158
159 struct file_extent_cluster cluster;
160
161 struct extent_io_tree processed_blocks;
162
163 struct mapping_tree reloc_root_tree;
164
165 struct list_head reloc_roots;
166
167 struct list_head dirty_subvol_roots;
168
169 u64 merging_rsv_size;
170
171 u64 nodes_relocated;
172
173 u64 reserved_bytes;
174
175 u64 search_start;
176 u64 extents_found;
177
178 unsigned int stage:8;
179 unsigned int create_reloc_tree:1;
180 unsigned int merge_reloc_tree:1;
181 unsigned int found_file_extent:1;
182};
183
184
185#define MOVE_DATA_EXTENTS 0
186#define UPDATE_DATA_PTRS 1
187
188static void remove_backref_node(struct backref_cache *cache,
189 struct backref_node *node);
190static void __mark_block_processed(struct reloc_control *rc,
191 struct backref_node *node);
192
193static void mapping_tree_init(struct mapping_tree *tree)
194{
195 tree->rb_root = RB_ROOT;
196 spin_lock_init(&tree->lock);
197}
198
199static void backref_cache_init(struct backref_cache *cache)
200{
201 int i;
202 cache->rb_root = RB_ROOT;
203 for (i = 0; i < BTRFS_MAX_LEVEL; i++)
204 INIT_LIST_HEAD(&cache->pending[i]);
205 INIT_LIST_HEAD(&cache->changed);
206 INIT_LIST_HEAD(&cache->detached);
207 INIT_LIST_HEAD(&cache->leaves);
208}
209
210static void backref_cache_cleanup(struct backref_cache *cache)
211{
212 struct backref_node *node;
213 int i;
214
215 while (!list_empty(&cache->detached)) {
216 node = list_entry(cache->detached.next,
217 struct backref_node, list);
218 remove_backref_node(cache, node);
219 }
220
221 while (!list_empty(&cache->leaves)) {
222 node = list_entry(cache->leaves.next,
223 struct backref_node, lower);
224 remove_backref_node(cache, node);
225 }
226
227 cache->last_trans = 0;
228
229 for (i = 0; i < BTRFS_MAX_LEVEL; i++)
230 ASSERT(list_empty(&cache->pending[i]));
231 ASSERT(list_empty(&cache->changed));
232 ASSERT(list_empty(&cache->detached));
233 ASSERT(RB_EMPTY_ROOT(&cache->rb_root));
234 ASSERT(!cache->nr_nodes);
235 ASSERT(!cache->nr_edges);
236}
237
238static struct backref_node *alloc_backref_node(struct backref_cache *cache)
239{
240 struct backref_node *node;
241
242 node = kzalloc(sizeof(*node), GFP_NOFS);
243 if (node) {
244 INIT_LIST_HEAD(&node->list);
245 INIT_LIST_HEAD(&node->upper);
246 INIT_LIST_HEAD(&node->lower);
247 RB_CLEAR_NODE(&node->rb_node);
248 cache->nr_nodes++;
249 }
250 return node;
251}
252
253static void free_backref_node(struct backref_cache *cache,
254 struct backref_node *node)
255{
256 if (node) {
257 cache->nr_nodes--;
258 kfree(node);
259 }
260}
261
262static struct backref_edge *alloc_backref_edge(struct backref_cache *cache)
263{
264 struct backref_edge *edge;
265
266 edge = kzalloc(sizeof(*edge), GFP_NOFS);
267 if (edge)
268 cache->nr_edges++;
269 return edge;
270}
271
272static void free_backref_edge(struct backref_cache *cache,
273 struct backref_edge *edge)
274{
275 if (edge) {
276 cache->nr_edges--;
277 kfree(edge);
278 }
279}
280
281static struct rb_node *tree_insert(struct rb_root *root, u64 bytenr,
282 struct rb_node *node)
283{
284 struct rb_node **p = &root->rb_node;
285 struct rb_node *parent = NULL;
286 struct tree_entry *entry;
287
288 while (*p) {
289 parent = *p;
290 entry = rb_entry(parent, struct tree_entry, rb_node);
291
292 if (bytenr < entry->bytenr)
293 p = &(*p)->rb_left;
294 else if (bytenr > entry->bytenr)
295 p = &(*p)->rb_right;
296 else
297 return parent;
298 }
299
300 rb_link_node(node, parent, p);
301 rb_insert_color(node, root);
302 return NULL;
303}
304
305static struct rb_node *tree_search(struct rb_root *root, u64 bytenr)
306{
307 struct rb_node *n = root->rb_node;
308 struct tree_entry *entry;
309
310 while (n) {
311 entry = rb_entry(n, struct tree_entry, rb_node);
312
313 if (bytenr < entry->bytenr)
314 n = n->rb_left;
315 else if (bytenr > entry->bytenr)
316 n = n->rb_right;
317 else
318 return n;
319 }
320 return NULL;
321}
322
323static void backref_tree_panic(struct rb_node *rb_node, int errno, u64 bytenr)
324{
325
326 struct btrfs_fs_info *fs_info = NULL;
327 struct backref_node *bnode = rb_entry(rb_node, struct backref_node,
328 rb_node);
329 if (bnode->root)
330 fs_info = bnode->root->fs_info;
331 btrfs_panic(fs_info, errno,
332 "Inconsistency in backref cache found at offset %llu",
333 bytenr);
334}
335
336
337
338
339static struct backref_node *walk_up_backref(struct backref_node *node,
340 struct backref_edge *edges[],
341 int *index)
342{
343 struct backref_edge *edge;
344 int idx = *index;
345
346 while (!list_empty(&node->upper)) {
347 edge = list_entry(node->upper.next,
348 struct backref_edge, list[LOWER]);
349 edges[idx++] = edge;
350 node = edge->node[UPPER];
351 }
352 BUG_ON(node->detached);
353 *index = idx;
354 return node;
355}
356
357
358
359
360static struct backref_node *walk_down_backref(struct backref_edge *edges[],
361 int *index)
362{
363 struct backref_edge *edge;
364 struct backref_node *lower;
365 int idx = *index;
366
367 while (idx > 0) {
368 edge = edges[idx - 1];
369 lower = edge->node[LOWER];
370 if (list_is_last(&edge->list[LOWER], &lower->upper)) {
371 idx--;
372 continue;
373 }
374 edge = list_entry(edge->list[LOWER].next,
375 struct backref_edge, list[LOWER]);
376 edges[idx - 1] = edge;
377 *index = idx;
378 return edge->node[UPPER];
379 }
380 *index = 0;
381 return NULL;
382}
383
384static void unlock_node_buffer(struct backref_node *node)
385{
386 if (node->locked) {
387 btrfs_tree_unlock(node->eb);
388 node->locked = 0;
389 }
390}
391
392static void drop_node_buffer(struct backref_node *node)
393{
394 if (node->eb) {
395 unlock_node_buffer(node);
396 free_extent_buffer(node->eb);
397 node->eb = NULL;
398 }
399}
400
401static void drop_backref_node(struct backref_cache *tree,
402 struct backref_node *node)
403{
404 BUG_ON(!list_empty(&node->upper));
405
406 drop_node_buffer(node);
407 list_del(&node->list);
408 list_del(&node->lower);
409 if (!RB_EMPTY_NODE(&node->rb_node))
410 rb_erase(&node->rb_node, &tree->rb_root);
411 free_backref_node(tree, node);
412}
413
414
415
416
417static void remove_backref_node(struct backref_cache *cache,
418 struct backref_node *node)
419{
420 struct backref_node *upper;
421 struct backref_edge *edge;
422
423 if (!node)
424 return;
425
426 BUG_ON(!node->lowest && !node->detached);
427 while (!list_empty(&node->upper)) {
428 edge = list_entry(node->upper.next, struct backref_edge,
429 list[LOWER]);
430 upper = edge->node[UPPER];
431 list_del(&edge->list[LOWER]);
432 list_del(&edge->list[UPPER]);
433 free_backref_edge(cache, edge);
434
435 if (RB_EMPTY_NODE(&upper->rb_node)) {
436 BUG_ON(!list_empty(&node->upper));
437 drop_backref_node(cache, node);
438 node = upper;
439 node->lowest = 1;
440 continue;
441 }
442
443
444
445
446 if (list_empty(&upper->lower)) {
447 list_add_tail(&upper->lower, &cache->leaves);
448 upper->lowest = 1;
449 }
450 }
451
452 drop_backref_node(cache, node);
453}
454
455static void update_backref_node(struct backref_cache *cache,
456 struct backref_node *node, u64 bytenr)
457{
458 struct rb_node *rb_node;
459 rb_erase(&node->rb_node, &cache->rb_root);
460 node->bytenr = bytenr;
461 rb_node = tree_insert(&cache->rb_root, node->bytenr, &node->rb_node);
462 if (rb_node)
463 backref_tree_panic(rb_node, -EEXIST, bytenr);
464}
465
466
467
468
469static int update_backref_cache(struct btrfs_trans_handle *trans,
470 struct backref_cache *cache)
471{
472 struct backref_node *node;
473 int level = 0;
474
475 if (cache->last_trans == 0) {
476 cache->last_trans = trans->transid;
477 return 0;
478 }
479
480 if (cache->last_trans == trans->transid)
481 return 0;
482
483
484
485
486
487
488 while (!list_empty(&cache->detached)) {
489 node = list_entry(cache->detached.next,
490 struct backref_node, list);
491 remove_backref_node(cache, node);
492 }
493
494 while (!list_empty(&cache->changed)) {
495 node = list_entry(cache->changed.next,
496 struct backref_node, list);
497 list_del_init(&node->list);
498 BUG_ON(node->pending);
499 update_backref_node(cache, node, node->new_bytenr);
500 }
501
502
503
504
505
506 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
507 list_for_each_entry(node, &cache->pending[level], list) {
508 BUG_ON(!node->pending);
509 if (node->bytenr == node->new_bytenr)
510 continue;
511 update_backref_node(cache, node, node->new_bytenr);
512 }
513 }
514
515 cache->last_trans = 0;
516 return 1;
517}
518
519
520static int should_ignore_root(struct btrfs_root *root)
521{
522 struct btrfs_root *reloc_root;
523
524 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
525 return 0;
526
527 reloc_root = root->reloc_root;
528 if (!reloc_root)
529 return 0;
530
531 if (btrfs_root_last_snapshot(&reloc_root->root_item) ==
532 root->fs_info->running_transaction->transid - 1)
533 return 0;
534
535
536
537
538
539
540 return 1;
541}
542
543
544
545static struct btrfs_root *find_reloc_root(struct reloc_control *rc,
546 u64 bytenr)
547{
548 struct rb_node *rb_node;
549 struct mapping_node *node;
550 struct btrfs_root *root = NULL;
551
552 spin_lock(&rc->reloc_root_tree.lock);
553 rb_node = tree_search(&rc->reloc_root_tree.rb_root, bytenr);
554 if (rb_node) {
555 node = rb_entry(rb_node, struct mapping_node, rb_node);
556 root = (struct btrfs_root *)node->data;
557 }
558 spin_unlock(&rc->reloc_root_tree.lock);
559 return root;
560}
561
562static int is_cowonly_root(u64 root_objectid)
563{
564 if (root_objectid == BTRFS_ROOT_TREE_OBJECTID ||
565 root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
566 root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
567 root_objectid == BTRFS_DEV_TREE_OBJECTID ||
568 root_objectid == BTRFS_TREE_LOG_OBJECTID ||
569 root_objectid == BTRFS_CSUM_TREE_OBJECTID ||
570 root_objectid == BTRFS_UUID_TREE_OBJECTID ||
571 root_objectid == BTRFS_QUOTA_TREE_OBJECTID ||
572 root_objectid == BTRFS_FREE_SPACE_TREE_OBJECTID)
573 return 1;
574 return 0;
575}
576
577static struct btrfs_root *read_fs_root(struct btrfs_fs_info *fs_info,
578 u64 root_objectid)
579{
580 struct btrfs_key key;
581
582 key.objectid = root_objectid;
583 key.type = BTRFS_ROOT_ITEM_KEY;
584 if (is_cowonly_root(root_objectid))
585 key.offset = 0;
586 else
587 key.offset = (u64)-1;
588
589 return btrfs_get_fs_root(fs_info, &key, false);
590}
591
592static noinline_for_stack
593int find_inline_backref(struct extent_buffer *leaf, int slot,
594 unsigned long *ptr, unsigned long *end)
595{
596 struct btrfs_key key;
597 struct btrfs_extent_item *ei;
598 struct btrfs_tree_block_info *bi;
599 u32 item_size;
600
601 btrfs_item_key_to_cpu(leaf, &key, slot);
602
603 item_size = btrfs_item_size_nr(leaf, slot);
604 if (item_size < sizeof(*ei)) {
605 btrfs_print_v0_err(leaf->fs_info);
606 btrfs_handle_fs_error(leaf->fs_info, -EINVAL, NULL);
607 return 1;
608 }
609 ei = btrfs_item_ptr(leaf, slot, struct btrfs_extent_item);
610 WARN_ON(!(btrfs_extent_flags(leaf, ei) &
611 BTRFS_EXTENT_FLAG_TREE_BLOCK));
612
613 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
614 item_size <= sizeof(*ei) + sizeof(*bi)) {
615 WARN_ON(item_size < sizeof(*ei) + sizeof(*bi));
616 return 1;
617 }
618 if (key.type == BTRFS_METADATA_ITEM_KEY &&
619 item_size <= sizeof(*ei)) {
620 WARN_ON(item_size < sizeof(*ei));
621 return 1;
622 }
623
624 if (key.type == BTRFS_EXTENT_ITEM_KEY) {
625 bi = (struct btrfs_tree_block_info *)(ei + 1);
626 *ptr = (unsigned long)(bi + 1);
627 } else {
628 *ptr = (unsigned long)(ei + 1);
629 }
630 *end = (unsigned long)ei + item_size;
631 return 0;
632}
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648static noinline_for_stack
649struct backref_node *build_backref_tree(struct reloc_control *rc,
650 struct btrfs_key *node_key,
651 int level, u64 bytenr)
652{
653 struct backref_cache *cache = &rc->backref_cache;
654 struct btrfs_path *path1;
655 struct btrfs_path *path2;
656 struct extent_buffer *eb;
657 struct btrfs_root *root;
658 struct backref_node *cur;
659 struct backref_node *upper;
660 struct backref_node *lower;
661 struct backref_node *node = NULL;
662 struct backref_node *exist = NULL;
663 struct backref_edge *edge;
664 struct rb_node *rb_node;
665 struct btrfs_key key;
666 unsigned long end;
667 unsigned long ptr;
668 LIST_HEAD(list);
669 LIST_HEAD(useless);
670 int cowonly;
671 int ret;
672 int err = 0;
673 bool need_check = true;
674
675 path1 = btrfs_alloc_path();
676 path2 = btrfs_alloc_path();
677 if (!path1 || !path2) {
678 err = -ENOMEM;
679 goto out;
680 }
681 path1->reada = READA_FORWARD;
682 path2->reada = READA_FORWARD;
683
684 node = alloc_backref_node(cache);
685 if (!node) {
686 err = -ENOMEM;
687 goto out;
688 }
689
690 node->bytenr = bytenr;
691 node->level = level;
692 node->lowest = 1;
693 cur = node;
694again:
695 end = 0;
696 ptr = 0;
697 key.objectid = cur->bytenr;
698 key.type = BTRFS_METADATA_ITEM_KEY;
699 key.offset = (u64)-1;
700
701 path1->search_commit_root = 1;
702 path1->skip_locking = 1;
703 ret = btrfs_search_slot(NULL, rc->extent_root, &key, path1,
704 0, 0);
705 if (ret < 0) {
706 err = ret;
707 goto out;
708 }
709 ASSERT(ret);
710 ASSERT(path1->slots[0]);
711
712 path1->slots[0]--;
713
714 WARN_ON(cur->checked);
715 if (!list_empty(&cur->upper)) {
716
717
718
719
720 ASSERT(list_is_singular(&cur->upper));
721 edge = list_entry(cur->upper.next, struct backref_edge,
722 list[LOWER]);
723 ASSERT(list_empty(&edge->list[UPPER]));
724 exist = edge->node[UPPER];
725
726
727
728
729 if (!exist->checked)
730 list_add_tail(&edge->list[UPPER], &list);
731 } else {
732 exist = NULL;
733 }
734
735 while (1) {
736 cond_resched();
737 eb = path1->nodes[0];
738
739 if (ptr >= end) {
740 if (path1->slots[0] >= btrfs_header_nritems(eb)) {
741 ret = btrfs_next_leaf(rc->extent_root, path1);
742 if (ret < 0) {
743 err = ret;
744 goto out;
745 }
746 if (ret > 0)
747 break;
748 eb = path1->nodes[0];
749 }
750
751 btrfs_item_key_to_cpu(eb, &key, path1->slots[0]);
752 if (key.objectid != cur->bytenr) {
753 WARN_ON(exist);
754 break;
755 }
756
757 if (key.type == BTRFS_EXTENT_ITEM_KEY ||
758 key.type == BTRFS_METADATA_ITEM_KEY) {
759 ret = find_inline_backref(eb, path1->slots[0],
760 &ptr, &end);
761 if (ret)
762 goto next;
763 }
764 }
765
766 if (ptr < end) {
767
768 struct btrfs_extent_inline_ref *iref;
769 int type;
770 iref = (struct btrfs_extent_inline_ref *)ptr;
771 type = btrfs_get_extent_inline_ref_type(eb, iref,
772 BTRFS_REF_TYPE_BLOCK);
773 if (type == BTRFS_REF_TYPE_INVALID) {
774 err = -EUCLEAN;
775 goto out;
776 }
777 key.type = type;
778 key.offset = btrfs_extent_inline_ref_offset(eb, iref);
779
780 WARN_ON(key.type != BTRFS_TREE_BLOCK_REF_KEY &&
781 key.type != BTRFS_SHARED_BLOCK_REF_KEY);
782 }
783
784
785
786
787
788 if (exist &&
789 ((key.type == BTRFS_TREE_BLOCK_REF_KEY &&
790 exist->owner == key.offset) ||
791 (key.type == BTRFS_SHARED_BLOCK_REF_KEY &&
792 exist->bytenr == key.offset))) {
793 exist = NULL;
794 goto next;
795 }
796
797
798 if (key.type == BTRFS_SHARED_BLOCK_REF_KEY) {
799 if (key.objectid == key.offset) {
800
801
802
803
804 root = find_reloc_root(rc, cur->bytenr);
805 ASSERT(root);
806 cur->root = root;
807 break;
808 }
809
810 edge = alloc_backref_edge(cache);
811 if (!edge) {
812 err = -ENOMEM;
813 goto out;
814 }
815 rb_node = tree_search(&cache->rb_root, key.offset);
816 if (!rb_node) {
817 upper = alloc_backref_node(cache);
818 if (!upper) {
819 free_backref_edge(cache, edge);
820 err = -ENOMEM;
821 goto out;
822 }
823 upper->bytenr = key.offset;
824 upper->level = cur->level + 1;
825
826
827
828
829 list_add_tail(&edge->list[UPPER], &list);
830 } else {
831 upper = rb_entry(rb_node, struct backref_node,
832 rb_node);
833 ASSERT(upper->checked);
834 INIT_LIST_HEAD(&edge->list[UPPER]);
835 }
836 list_add_tail(&edge->list[LOWER], &cur->upper);
837 edge->node[LOWER] = cur;
838 edge->node[UPPER] = upper;
839
840 goto next;
841 } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) {
842 err = -EINVAL;
843 btrfs_print_v0_err(rc->extent_root->fs_info);
844 btrfs_handle_fs_error(rc->extent_root->fs_info, err,
845 NULL);
846 goto out;
847 } else if (key.type != BTRFS_TREE_BLOCK_REF_KEY) {
848 goto next;
849 }
850
851
852
853
854
855
856 root = read_fs_root(rc->extent_root->fs_info, key.offset);
857 if (IS_ERR(root)) {
858 err = PTR_ERR(root);
859 goto out;
860 }
861
862 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
863 cur->cowonly = 1;
864
865 if (btrfs_root_level(&root->root_item) == cur->level) {
866
867 ASSERT(btrfs_root_bytenr(&root->root_item) ==
868 cur->bytenr);
869 if (should_ignore_root(root))
870 list_add(&cur->list, &useless);
871 else
872 cur->root = root;
873 break;
874 }
875
876 level = cur->level + 1;
877
878
879 path2->search_commit_root = 1;
880 path2->skip_locking = 1;
881 path2->lowest_level = level;
882 ret = btrfs_search_slot(NULL, root, node_key, path2, 0, 0);
883 path2->lowest_level = 0;
884 if (ret < 0) {
885 err = ret;
886 goto out;
887 }
888 if (ret > 0 && path2->slots[level] > 0)
889 path2->slots[level]--;
890
891 eb = path2->nodes[level];
892 if (btrfs_node_blockptr(eb, path2->slots[level]) !=
893 cur->bytenr) {
894 btrfs_err(root->fs_info,
895 "couldn't find block (%llu) (level %d) in tree (%llu) with key (%llu %u %llu)",
896 cur->bytenr, level - 1,
897 root->root_key.objectid,
898 node_key->objectid, node_key->type,
899 node_key->offset);
900 err = -ENOENT;
901 goto out;
902 }
903 lower = cur;
904 need_check = true;
905
906
907 for (; level < BTRFS_MAX_LEVEL; level++) {
908 if (!path2->nodes[level]) {
909 ASSERT(btrfs_root_bytenr(&root->root_item) ==
910 lower->bytenr);
911 if (should_ignore_root(root))
912 list_add(&lower->list, &useless);
913 else
914 lower->root = root;
915 break;
916 }
917
918 edge = alloc_backref_edge(cache);
919 if (!edge) {
920 err = -ENOMEM;
921 goto out;
922 }
923
924 eb = path2->nodes[level];
925 rb_node = tree_search(&cache->rb_root, eb->start);
926 if (!rb_node) {
927 upper = alloc_backref_node(cache);
928 if (!upper) {
929 free_backref_edge(cache, edge);
930 err = -ENOMEM;
931 goto out;
932 }
933 upper->bytenr = eb->start;
934 upper->owner = btrfs_header_owner(eb);
935 upper->level = lower->level + 1;
936 if (!test_bit(BTRFS_ROOT_REF_COWS,
937 &root->state))
938 upper->cowonly = 1;
939
940
941
942
943
944 if (btrfs_block_can_be_shared(root, eb))
945 upper->checked = 0;
946 else
947 upper->checked = 1;
948
949
950
951
952
953
954
955 if (!upper->checked && need_check) {
956 need_check = false;
957 list_add_tail(&edge->list[UPPER],
958 &list);
959 } else {
960 if (upper->checked)
961 need_check = true;
962 INIT_LIST_HEAD(&edge->list[UPPER]);
963 }
964 } else {
965 upper = rb_entry(rb_node, struct backref_node,
966 rb_node);
967 ASSERT(upper->checked);
968 INIT_LIST_HEAD(&edge->list[UPPER]);
969 if (!upper->owner)
970 upper->owner = btrfs_header_owner(eb);
971 }
972 list_add_tail(&edge->list[LOWER], &lower->upper);
973 edge->node[LOWER] = lower;
974 edge->node[UPPER] = upper;
975
976 if (rb_node)
977 break;
978 lower = upper;
979 upper = NULL;
980 }
981 btrfs_release_path(path2);
982next:
983 if (ptr < end) {
984 ptr += btrfs_extent_inline_ref_size(key.type);
985 if (ptr >= end) {
986 WARN_ON(ptr > end);
987 ptr = 0;
988 end = 0;
989 }
990 }
991 if (ptr >= end)
992 path1->slots[0]++;
993 }
994 btrfs_release_path(path1);
995
996 cur->checked = 1;
997 WARN_ON(exist);
998
999
1000 if (!list_empty(&list)) {
1001 edge = list_entry(list.next, struct backref_edge, list[UPPER]);
1002 list_del_init(&edge->list[UPPER]);
1003 cur = edge->node[UPPER];
1004 goto again;
1005 }
1006
1007
1008
1009
1010
1011 ASSERT(node->checked);
1012 cowonly = node->cowonly;
1013 if (!cowonly) {
1014 rb_node = tree_insert(&cache->rb_root, node->bytenr,
1015 &node->rb_node);
1016 if (rb_node)
1017 backref_tree_panic(rb_node, -EEXIST, node->bytenr);
1018 list_add_tail(&node->lower, &cache->leaves);
1019 }
1020
1021 list_for_each_entry(edge, &node->upper, list[LOWER])
1022 list_add_tail(&edge->list[UPPER], &list);
1023
1024 while (!list_empty(&list)) {
1025 edge = list_entry(list.next, struct backref_edge, list[UPPER]);
1026 list_del_init(&edge->list[UPPER]);
1027 upper = edge->node[UPPER];
1028 if (upper->detached) {
1029 list_del(&edge->list[LOWER]);
1030 lower = edge->node[LOWER];
1031 free_backref_edge(cache, edge);
1032 if (list_empty(&lower->upper))
1033 list_add(&lower->list, &useless);
1034 continue;
1035 }
1036
1037 if (!RB_EMPTY_NODE(&upper->rb_node)) {
1038 if (upper->lowest) {
1039 list_del_init(&upper->lower);
1040 upper->lowest = 0;
1041 }
1042
1043 list_add_tail(&edge->list[UPPER], &upper->lower);
1044 continue;
1045 }
1046
1047 if (!upper->checked) {
1048
1049
1050
1051
1052 ASSERT(0);
1053 err = -EINVAL;
1054 goto out;
1055 }
1056 if (cowonly != upper->cowonly) {
1057 ASSERT(0);
1058 err = -EINVAL;
1059 goto out;
1060 }
1061
1062 if (!cowonly) {
1063 rb_node = tree_insert(&cache->rb_root, upper->bytenr,
1064 &upper->rb_node);
1065 if (rb_node)
1066 backref_tree_panic(rb_node, -EEXIST,
1067 upper->bytenr);
1068 }
1069
1070 list_add_tail(&edge->list[UPPER], &upper->lower);
1071
1072 list_for_each_entry(edge, &upper->upper, list[LOWER])
1073 list_add_tail(&edge->list[UPPER], &list);
1074 }
1075
1076
1077
1078
1079
1080
1081 while (!list_empty(&useless)) {
1082 upper = list_entry(useless.next, struct backref_node, list);
1083 list_del_init(&upper->list);
1084 ASSERT(list_empty(&upper->upper));
1085 if (upper == node)
1086 node = NULL;
1087 if (upper->lowest) {
1088 list_del_init(&upper->lower);
1089 upper->lowest = 0;
1090 }
1091 while (!list_empty(&upper->lower)) {
1092 edge = list_entry(upper->lower.next,
1093 struct backref_edge, list[UPPER]);
1094 list_del(&edge->list[UPPER]);
1095 list_del(&edge->list[LOWER]);
1096 lower = edge->node[LOWER];
1097 free_backref_edge(cache, edge);
1098
1099 if (list_empty(&lower->upper))
1100 list_add(&lower->list, &useless);
1101 }
1102 __mark_block_processed(rc, upper);
1103 if (upper->level > 0) {
1104 list_add(&upper->list, &cache->detached);
1105 upper->detached = 1;
1106 } else {
1107 rb_erase(&upper->rb_node, &cache->rb_root);
1108 free_backref_node(cache, upper);
1109 }
1110 }
1111out:
1112 btrfs_free_path(path1);
1113 btrfs_free_path(path2);
1114 if (err) {
1115 while (!list_empty(&useless)) {
1116 lower = list_entry(useless.next,
1117 struct backref_node, list);
1118 list_del_init(&lower->list);
1119 }
1120 while (!list_empty(&list)) {
1121 edge = list_first_entry(&list, struct backref_edge,
1122 list[UPPER]);
1123 list_del(&edge->list[UPPER]);
1124 list_del(&edge->list[LOWER]);
1125 lower = edge->node[LOWER];
1126 upper = edge->node[UPPER];
1127 free_backref_edge(cache, edge);
1128
1129
1130
1131
1132
1133 if (list_empty(&lower->upper) &&
1134 RB_EMPTY_NODE(&lower->rb_node))
1135 list_add(&lower->list, &useless);
1136
1137 if (!RB_EMPTY_NODE(&upper->rb_node))
1138 continue;
1139
1140
1141 list_for_each_entry(edge, &upper->upper, list[LOWER])
1142 list_add_tail(&edge->list[UPPER], &list);
1143 if (list_empty(&upper->upper))
1144 list_add(&upper->list, &useless);
1145 }
1146
1147 while (!list_empty(&useless)) {
1148 lower = list_entry(useless.next,
1149 struct backref_node, list);
1150 list_del_init(&lower->list);
1151 if (lower == node)
1152 node = NULL;
1153 free_backref_node(cache, lower);
1154 }
1155
1156 free_backref_node(cache, node);
1157 return ERR_PTR(err);
1158 }
1159 ASSERT(!node || !node->detached);
1160 return node;
1161}
1162
1163
1164
1165
1166
1167
1168static int clone_backref_node(struct btrfs_trans_handle *trans,
1169 struct reloc_control *rc,
1170 struct btrfs_root *src,
1171 struct btrfs_root *dest)
1172{
1173 struct btrfs_root *reloc_root = src->reloc_root;
1174 struct backref_cache *cache = &rc->backref_cache;
1175 struct backref_node *node = NULL;
1176 struct backref_node *new_node;
1177 struct backref_edge *edge;
1178 struct backref_edge *new_edge;
1179 struct rb_node *rb_node;
1180
1181 if (cache->last_trans > 0)
1182 update_backref_cache(trans, cache);
1183
1184 rb_node = tree_search(&cache->rb_root, src->commit_root->start);
1185 if (rb_node) {
1186 node = rb_entry(rb_node, struct backref_node, rb_node);
1187 if (node->detached)
1188 node = NULL;
1189 else
1190 BUG_ON(node->new_bytenr != reloc_root->node->start);
1191 }
1192
1193 if (!node) {
1194 rb_node = tree_search(&cache->rb_root,
1195 reloc_root->commit_root->start);
1196 if (rb_node) {
1197 node = rb_entry(rb_node, struct backref_node,
1198 rb_node);
1199 BUG_ON(node->detached);
1200 }
1201 }
1202
1203 if (!node)
1204 return 0;
1205
1206 new_node = alloc_backref_node(cache);
1207 if (!new_node)
1208 return -ENOMEM;
1209
1210 new_node->bytenr = dest->node->start;
1211 new_node->level = node->level;
1212 new_node->lowest = node->lowest;
1213 new_node->checked = 1;
1214 new_node->root = dest;
1215
1216 if (!node->lowest) {
1217 list_for_each_entry(edge, &node->lower, list[UPPER]) {
1218 new_edge = alloc_backref_edge(cache);
1219 if (!new_edge)
1220 goto fail;
1221
1222 new_edge->node[UPPER] = new_node;
1223 new_edge->node[LOWER] = edge->node[LOWER];
1224 list_add_tail(&new_edge->list[UPPER],
1225 &new_node->lower);
1226 }
1227 } else {
1228 list_add_tail(&new_node->lower, &cache->leaves);
1229 }
1230
1231 rb_node = tree_insert(&cache->rb_root, new_node->bytenr,
1232 &new_node->rb_node);
1233 if (rb_node)
1234 backref_tree_panic(rb_node, -EEXIST, new_node->bytenr);
1235
1236 if (!new_node->lowest) {
1237 list_for_each_entry(new_edge, &new_node->lower, list[UPPER]) {
1238 list_add_tail(&new_edge->list[LOWER],
1239 &new_edge->node[LOWER]->upper);
1240 }
1241 }
1242 return 0;
1243fail:
1244 while (!list_empty(&new_node->lower)) {
1245 new_edge = list_entry(new_node->lower.next,
1246 struct backref_edge, list[UPPER]);
1247 list_del(&new_edge->list[UPPER]);
1248 free_backref_edge(cache, new_edge);
1249 }
1250 free_backref_node(cache, new_node);
1251 return -ENOMEM;
1252}
1253
1254
1255
1256
1257static int __must_check __add_reloc_root(struct btrfs_root *root)
1258{
1259 struct btrfs_fs_info *fs_info = root->fs_info;
1260 struct rb_node *rb_node;
1261 struct mapping_node *node;
1262 struct reloc_control *rc = fs_info->reloc_ctl;
1263
1264 node = kmalloc(sizeof(*node), GFP_NOFS);
1265 if (!node)
1266 return -ENOMEM;
1267
1268 node->bytenr = root->node->start;
1269 node->data = root;
1270
1271 spin_lock(&rc->reloc_root_tree.lock);
1272 rb_node = tree_insert(&rc->reloc_root_tree.rb_root,
1273 node->bytenr, &node->rb_node);
1274 spin_unlock(&rc->reloc_root_tree.lock);
1275 if (rb_node) {
1276 btrfs_panic(fs_info, -EEXIST,
1277 "Duplicate root found for start=%llu while inserting into relocation tree",
1278 node->bytenr);
1279 }
1280
1281 list_add_tail(&root->root_list, &rc->reloc_roots);
1282 return 0;
1283}
1284
1285
1286
1287
1288
1289static void __del_reloc_root(struct btrfs_root *root)
1290{
1291 struct btrfs_fs_info *fs_info = root->fs_info;
1292 struct rb_node *rb_node;
1293 struct mapping_node *node = NULL;
1294 struct reloc_control *rc = fs_info->reloc_ctl;
1295
1296 if (rc && root->node) {
1297 spin_lock(&rc->reloc_root_tree.lock);
1298 rb_node = tree_search(&rc->reloc_root_tree.rb_root,
1299 root->node->start);
1300 if (rb_node) {
1301 node = rb_entry(rb_node, struct mapping_node, rb_node);
1302 rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root);
1303 }
1304 spin_unlock(&rc->reloc_root_tree.lock);
1305 if (!node)
1306 return;
1307 BUG_ON((struct btrfs_root *)node->data != root);
1308 }
1309
1310 spin_lock(&fs_info->trans_lock);
1311 list_del_init(&root->root_list);
1312 spin_unlock(&fs_info->trans_lock);
1313 kfree(node);
1314}
1315
1316
1317
1318
1319
1320static int __update_reloc_root(struct btrfs_root *root, u64 new_bytenr)
1321{
1322 struct btrfs_fs_info *fs_info = root->fs_info;
1323 struct rb_node *rb_node;
1324 struct mapping_node *node = NULL;
1325 struct reloc_control *rc = fs_info->reloc_ctl;
1326
1327 spin_lock(&rc->reloc_root_tree.lock);
1328 rb_node = tree_search(&rc->reloc_root_tree.rb_root,
1329 root->node->start);
1330 if (rb_node) {
1331 node = rb_entry(rb_node, struct mapping_node, rb_node);
1332 rb_erase(&node->rb_node, &rc->reloc_root_tree.rb_root);
1333 }
1334 spin_unlock(&rc->reloc_root_tree.lock);
1335
1336 if (!node)
1337 return 0;
1338 BUG_ON((struct btrfs_root *)node->data != root);
1339
1340 spin_lock(&rc->reloc_root_tree.lock);
1341 node->bytenr = new_bytenr;
1342 rb_node = tree_insert(&rc->reloc_root_tree.rb_root,
1343 node->bytenr, &node->rb_node);
1344 spin_unlock(&rc->reloc_root_tree.lock);
1345 if (rb_node)
1346 backref_tree_panic(rb_node, -EEXIST, node->bytenr);
1347 return 0;
1348}
1349
1350static struct btrfs_root *create_reloc_root(struct btrfs_trans_handle *trans,
1351 struct btrfs_root *root, u64 objectid)
1352{
1353 struct btrfs_fs_info *fs_info = root->fs_info;
1354 struct btrfs_root *reloc_root;
1355 struct extent_buffer *eb;
1356 struct btrfs_root_item *root_item;
1357 struct btrfs_key root_key;
1358 int ret;
1359
1360 root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
1361 BUG_ON(!root_item);
1362
1363 root_key.objectid = BTRFS_TREE_RELOC_OBJECTID;
1364 root_key.type = BTRFS_ROOT_ITEM_KEY;
1365 root_key.offset = objectid;
1366
1367 if (root->root_key.objectid == objectid) {
1368 u64 commit_root_gen;
1369
1370
1371 ret = btrfs_copy_root(trans, root, root->commit_root, &eb,
1372 BTRFS_TREE_RELOC_OBJECTID);
1373 BUG_ON(ret);
1374
1375
1376
1377
1378
1379
1380
1381
1382 commit_root_gen = btrfs_header_generation(root->commit_root);
1383 btrfs_set_root_last_snapshot(&root->root_item, commit_root_gen);
1384 } else {
1385
1386
1387
1388
1389
1390
1391
1392 ret = btrfs_copy_root(trans, root, root->node, &eb,
1393 BTRFS_TREE_RELOC_OBJECTID);
1394 BUG_ON(ret);
1395 }
1396
1397 memcpy(root_item, &root->root_item, sizeof(*root_item));
1398 btrfs_set_root_bytenr(root_item, eb->start);
1399 btrfs_set_root_level(root_item, btrfs_header_level(eb));
1400 btrfs_set_root_generation(root_item, trans->transid);
1401
1402 if (root->root_key.objectid == objectid) {
1403 btrfs_set_root_refs(root_item, 0);
1404 memset(&root_item->drop_progress, 0,
1405 sizeof(struct btrfs_disk_key));
1406 root_item->drop_level = 0;
1407 }
1408
1409 btrfs_tree_unlock(eb);
1410 free_extent_buffer(eb);
1411
1412 ret = btrfs_insert_root(trans, fs_info->tree_root,
1413 &root_key, root_item);
1414 BUG_ON(ret);
1415 kfree(root_item);
1416
1417 reloc_root = btrfs_read_fs_root(fs_info->tree_root, &root_key);
1418 BUG_ON(IS_ERR(reloc_root));
1419 reloc_root->last_trans = trans->transid;
1420 return reloc_root;
1421}
1422
1423
1424
1425
1426
1427int btrfs_init_reloc_root(struct btrfs_trans_handle *trans,
1428 struct btrfs_root *root)
1429{
1430 struct btrfs_fs_info *fs_info = root->fs_info;
1431 struct btrfs_root *reloc_root;
1432 struct reloc_control *rc = fs_info->reloc_ctl;
1433 struct btrfs_block_rsv *rsv;
1434 int clear_rsv = 0;
1435 int ret;
1436
1437 if (root->reloc_root) {
1438 reloc_root = root->reloc_root;
1439 reloc_root->last_trans = trans->transid;
1440 return 0;
1441 }
1442
1443 if (!rc || !rc->create_reloc_tree ||
1444 root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
1445 return 0;
1446
1447 if (!trans->reloc_reserved) {
1448 rsv = trans->block_rsv;
1449 trans->block_rsv = rc->block_rsv;
1450 clear_rsv = 1;
1451 }
1452 reloc_root = create_reloc_root(trans, root, root->root_key.objectid);
1453 if (clear_rsv)
1454 trans->block_rsv = rsv;
1455
1456 ret = __add_reloc_root(reloc_root);
1457 BUG_ON(ret < 0);
1458 root->reloc_root = reloc_root;
1459 return 0;
1460}
1461
1462
1463
1464
1465int btrfs_update_reloc_root(struct btrfs_trans_handle *trans,
1466 struct btrfs_root *root)
1467{
1468 struct btrfs_fs_info *fs_info = root->fs_info;
1469 struct btrfs_root *reloc_root;
1470 struct btrfs_root_item *root_item;
1471 int ret;
1472
1473 if (test_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state) ||
1474 !root->reloc_root)
1475 goto out;
1476
1477 reloc_root = root->reloc_root;
1478 root_item = &reloc_root->root_item;
1479
1480
1481 if (fs_info->reloc_ctl->merge_reloc_tree &&
1482 btrfs_root_refs(root_item) == 0) {
1483 set_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state);
1484 __del_reloc_root(reloc_root);
1485 }
1486
1487 if (reloc_root->commit_root != reloc_root->node) {
1488 btrfs_set_root_node(root_item, reloc_root->node);
1489 free_extent_buffer(reloc_root->commit_root);
1490 reloc_root->commit_root = btrfs_root_node(reloc_root);
1491 }
1492
1493 ret = btrfs_update_root(trans, fs_info->tree_root,
1494 &reloc_root->root_key, root_item);
1495 BUG_ON(ret);
1496
1497out:
1498 return 0;
1499}
1500
1501
1502
1503
1504
1505static struct inode *find_next_inode(struct btrfs_root *root, u64 objectid)
1506{
1507 struct rb_node *node;
1508 struct rb_node *prev;
1509 struct btrfs_inode *entry;
1510 struct inode *inode;
1511
1512 spin_lock(&root->inode_lock);
1513again:
1514 node = root->inode_tree.rb_node;
1515 prev = NULL;
1516 while (node) {
1517 prev = node;
1518 entry = rb_entry(node, struct btrfs_inode, rb_node);
1519
1520 if (objectid < btrfs_ino(entry))
1521 node = node->rb_left;
1522 else if (objectid > btrfs_ino(entry))
1523 node = node->rb_right;
1524 else
1525 break;
1526 }
1527 if (!node) {
1528 while (prev) {
1529 entry = rb_entry(prev, struct btrfs_inode, rb_node);
1530 if (objectid <= btrfs_ino(entry)) {
1531 node = prev;
1532 break;
1533 }
1534 prev = rb_next(prev);
1535 }
1536 }
1537 while (node) {
1538 entry = rb_entry(node, struct btrfs_inode, rb_node);
1539 inode = igrab(&entry->vfs_inode);
1540 if (inode) {
1541 spin_unlock(&root->inode_lock);
1542 return inode;
1543 }
1544
1545 objectid = btrfs_ino(entry) + 1;
1546 if (cond_resched_lock(&root->inode_lock))
1547 goto again;
1548
1549 node = rb_next(node);
1550 }
1551 spin_unlock(&root->inode_lock);
1552 return NULL;
1553}
1554
1555static int in_block_group(u64 bytenr,
1556 struct btrfs_block_group_cache *block_group)
1557{
1558 if (bytenr >= block_group->key.objectid &&
1559 bytenr < block_group->key.objectid + block_group->key.offset)
1560 return 1;
1561 return 0;
1562}
1563
1564
1565
1566
1567static int get_new_location(struct inode *reloc_inode, u64 *new_bytenr,
1568 u64 bytenr, u64 num_bytes)
1569{
1570 struct btrfs_root *root = BTRFS_I(reloc_inode)->root;
1571 struct btrfs_path *path;
1572 struct btrfs_file_extent_item *fi;
1573 struct extent_buffer *leaf;
1574 int ret;
1575
1576 path = btrfs_alloc_path();
1577 if (!path)
1578 return -ENOMEM;
1579
1580 bytenr -= BTRFS_I(reloc_inode)->index_cnt;
1581 ret = btrfs_lookup_file_extent(NULL, root, path,
1582 btrfs_ino(BTRFS_I(reloc_inode)), bytenr, 0);
1583 if (ret < 0)
1584 goto out;
1585 if (ret > 0) {
1586 ret = -ENOENT;
1587 goto out;
1588 }
1589
1590 leaf = path->nodes[0];
1591 fi = btrfs_item_ptr(leaf, path->slots[0],
1592 struct btrfs_file_extent_item);
1593
1594 BUG_ON(btrfs_file_extent_offset(leaf, fi) ||
1595 btrfs_file_extent_compression(leaf, fi) ||
1596 btrfs_file_extent_encryption(leaf, fi) ||
1597 btrfs_file_extent_other_encoding(leaf, fi));
1598
1599 if (num_bytes != btrfs_file_extent_disk_num_bytes(leaf, fi)) {
1600 ret = -EINVAL;
1601 goto out;
1602 }
1603
1604 *new_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1605 ret = 0;
1606out:
1607 btrfs_free_path(path);
1608 return ret;
1609}
1610
1611
1612
1613
1614
1615static noinline_for_stack
1616int replace_file_extents(struct btrfs_trans_handle *trans,
1617 struct reloc_control *rc,
1618 struct btrfs_root *root,
1619 struct extent_buffer *leaf)
1620{
1621 struct btrfs_fs_info *fs_info = root->fs_info;
1622 struct btrfs_key key;
1623 struct btrfs_file_extent_item *fi;
1624 struct inode *inode = NULL;
1625 u64 parent;
1626 u64 bytenr;
1627 u64 new_bytenr = 0;
1628 u64 num_bytes;
1629 u64 end;
1630 u32 nritems;
1631 u32 i;
1632 int ret = 0;
1633 int first = 1;
1634 int dirty = 0;
1635
1636 if (rc->stage != UPDATE_DATA_PTRS)
1637 return 0;
1638
1639
1640 if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID)
1641 parent = leaf->start;
1642 else
1643 parent = 0;
1644
1645 nritems = btrfs_header_nritems(leaf);
1646 for (i = 0; i < nritems; i++) {
1647 struct btrfs_ref ref = { 0 };
1648
1649 cond_resched();
1650 btrfs_item_key_to_cpu(leaf, &key, i);
1651 if (key.type != BTRFS_EXTENT_DATA_KEY)
1652 continue;
1653 fi = btrfs_item_ptr(leaf, i, struct btrfs_file_extent_item);
1654 if (btrfs_file_extent_type(leaf, fi) ==
1655 BTRFS_FILE_EXTENT_INLINE)
1656 continue;
1657 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
1658 num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi);
1659 if (bytenr == 0)
1660 continue;
1661 if (!in_block_group(bytenr, rc->block_group))
1662 continue;
1663
1664
1665
1666
1667
1668 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
1669 if (first) {
1670 inode = find_next_inode(root, key.objectid);
1671 first = 0;
1672 } else if (inode && btrfs_ino(BTRFS_I(inode)) < key.objectid) {
1673 btrfs_add_delayed_iput(inode);
1674 inode = find_next_inode(root, key.objectid);
1675 }
1676 if (inode && btrfs_ino(BTRFS_I(inode)) == key.objectid) {
1677 end = key.offset +
1678 btrfs_file_extent_num_bytes(leaf, fi);
1679 WARN_ON(!IS_ALIGNED(key.offset,
1680 fs_info->sectorsize));
1681 WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize));
1682 end--;
1683 ret = try_lock_extent(&BTRFS_I(inode)->io_tree,
1684 key.offset, end);
1685 if (!ret)
1686 continue;
1687
1688 btrfs_drop_extent_cache(BTRFS_I(inode),
1689 key.offset, end, 1);
1690 unlock_extent(&BTRFS_I(inode)->io_tree,
1691 key.offset, end);
1692 }
1693 }
1694
1695 ret = get_new_location(rc->data_inode, &new_bytenr,
1696 bytenr, num_bytes);
1697 if (ret) {
1698
1699
1700
1701
1702 break;
1703 }
1704
1705 btrfs_set_file_extent_disk_bytenr(leaf, fi, new_bytenr);
1706 dirty = 1;
1707
1708 key.offset -= btrfs_file_extent_offset(leaf, fi);
1709 btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr,
1710 num_bytes, parent);
1711 ref.real_root = root->root_key.objectid;
1712 btrfs_init_data_ref(&ref, btrfs_header_owner(leaf),
1713 key.objectid, key.offset);
1714 ret = btrfs_inc_extent_ref(trans, &ref);
1715 if (ret) {
1716 btrfs_abort_transaction(trans, ret);
1717 break;
1718 }
1719
1720 btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, bytenr,
1721 num_bytes, parent);
1722 ref.real_root = root->root_key.objectid;
1723 btrfs_init_data_ref(&ref, btrfs_header_owner(leaf),
1724 key.objectid, key.offset);
1725 ret = btrfs_free_extent(trans, &ref);
1726 if (ret) {
1727 btrfs_abort_transaction(trans, ret);
1728 break;
1729 }
1730 }
1731 if (dirty)
1732 btrfs_mark_buffer_dirty(leaf);
1733 if (inode)
1734 btrfs_add_delayed_iput(inode);
1735 return ret;
1736}
1737
1738static noinline_for_stack
1739int memcmp_node_keys(struct extent_buffer *eb, int slot,
1740 struct btrfs_path *path, int level)
1741{
1742 struct btrfs_disk_key key1;
1743 struct btrfs_disk_key key2;
1744 btrfs_node_key(eb, &key1, slot);
1745 btrfs_node_key(path->nodes[level], &key2, path->slots[level]);
1746 return memcmp(&key1, &key2, sizeof(key1));
1747}
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758static noinline_for_stack
1759int replace_path(struct btrfs_trans_handle *trans, struct reloc_control *rc,
1760 struct btrfs_root *dest, struct btrfs_root *src,
1761 struct btrfs_path *path, struct btrfs_key *next_key,
1762 int lowest_level, int max_level)
1763{
1764 struct btrfs_fs_info *fs_info = dest->fs_info;
1765 struct extent_buffer *eb;
1766 struct extent_buffer *parent;
1767 struct btrfs_ref ref = { 0 };
1768 struct btrfs_key key;
1769 u64 old_bytenr;
1770 u64 new_bytenr;
1771 u64 old_ptr_gen;
1772 u64 new_ptr_gen;
1773 u64 last_snapshot;
1774 u32 blocksize;
1775 int cow = 0;
1776 int level;
1777 int ret;
1778 int slot;
1779
1780 BUG_ON(src->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
1781 BUG_ON(dest->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID);
1782
1783 last_snapshot = btrfs_root_last_snapshot(&src->root_item);
1784again:
1785 slot = path->slots[lowest_level];
1786 btrfs_node_key_to_cpu(path->nodes[lowest_level], &key, slot);
1787
1788 eb = btrfs_lock_root_node(dest);
1789 btrfs_set_lock_blocking_write(eb);
1790 level = btrfs_header_level(eb);
1791
1792 if (level < lowest_level) {
1793 btrfs_tree_unlock(eb);
1794 free_extent_buffer(eb);
1795 return 0;
1796 }
1797
1798 if (cow) {
1799 ret = btrfs_cow_block(trans, dest, eb, NULL, 0, &eb);
1800 BUG_ON(ret);
1801 }
1802 btrfs_set_lock_blocking_write(eb);
1803
1804 if (next_key) {
1805 next_key->objectid = (u64)-1;
1806 next_key->type = (u8)-1;
1807 next_key->offset = (u64)-1;
1808 }
1809
1810 parent = eb;
1811 while (1) {
1812 struct btrfs_key first_key;
1813
1814 level = btrfs_header_level(parent);
1815 BUG_ON(level < lowest_level);
1816
1817 ret = btrfs_bin_search(parent, &key, level, &slot);
1818 if (ret < 0)
1819 break;
1820 if (ret && slot > 0)
1821 slot--;
1822
1823 if (next_key && slot + 1 < btrfs_header_nritems(parent))
1824 btrfs_node_key_to_cpu(parent, next_key, slot + 1);
1825
1826 old_bytenr = btrfs_node_blockptr(parent, slot);
1827 blocksize = fs_info->nodesize;
1828 old_ptr_gen = btrfs_node_ptr_generation(parent, slot);
1829 btrfs_node_key_to_cpu(parent, &first_key, slot);
1830
1831 if (level <= max_level) {
1832 eb = path->nodes[level];
1833 new_bytenr = btrfs_node_blockptr(eb,
1834 path->slots[level]);
1835 new_ptr_gen = btrfs_node_ptr_generation(eb,
1836 path->slots[level]);
1837 } else {
1838 new_bytenr = 0;
1839 new_ptr_gen = 0;
1840 }
1841
1842 if (WARN_ON(new_bytenr > 0 && new_bytenr == old_bytenr)) {
1843 ret = level;
1844 break;
1845 }
1846
1847 if (new_bytenr == 0 || old_ptr_gen > last_snapshot ||
1848 memcmp_node_keys(parent, slot, path, level)) {
1849 if (level <= lowest_level) {
1850 ret = 0;
1851 break;
1852 }
1853
1854 eb = read_tree_block(fs_info, old_bytenr, old_ptr_gen,
1855 level - 1, &first_key);
1856 if (IS_ERR(eb)) {
1857 ret = PTR_ERR(eb);
1858 break;
1859 } else if (!extent_buffer_uptodate(eb)) {
1860 ret = -EIO;
1861 free_extent_buffer(eb);
1862 break;
1863 }
1864 btrfs_tree_lock(eb);
1865 if (cow) {
1866 ret = btrfs_cow_block(trans, dest, eb, parent,
1867 slot, &eb);
1868 BUG_ON(ret);
1869 }
1870 btrfs_set_lock_blocking_write(eb);
1871
1872 btrfs_tree_unlock(parent);
1873 free_extent_buffer(parent);
1874
1875 parent = eb;
1876 continue;
1877 }
1878
1879 if (!cow) {
1880 btrfs_tree_unlock(parent);
1881 free_extent_buffer(parent);
1882 cow = 1;
1883 goto again;
1884 }
1885
1886 btrfs_node_key_to_cpu(path->nodes[level], &key,
1887 path->slots[level]);
1888 btrfs_release_path(path);
1889
1890 path->lowest_level = level;
1891 ret = btrfs_search_slot(trans, src, &key, path, 0, 1);
1892 path->lowest_level = 0;
1893 BUG_ON(ret);
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909 ret = btrfs_qgroup_add_swapped_blocks(trans, dest,
1910 rc->block_group, parent, slot,
1911 path->nodes[level], path->slots[level],
1912 last_snapshot);
1913 if (ret < 0)
1914 break;
1915
1916
1917
1918 btrfs_set_node_blockptr(parent, slot, new_bytenr);
1919 btrfs_set_node_ptr_generation(parent, slot, new_ptr_gen);
1920 btrfs_mark_buffer_dirty(parent);
1921
1922 btrfs_set_node_blockptr(path->nodes[level],
1923 path->slots[level], old_bytenr);
1924 btrfs_set_node_ptr_generation(path->nodes[level],
1925 path->slots[level], old_ptr_gen);
1926 btrfs_mark_buffer_dirty(path->nodes[level]);
1927
1928 btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, old_bytenr,
1929 blocksize, path->nodes[level]->start);
1930 ref.skip_qgroup = true;
1931 btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid);
1932 ret = btrfs_inc_extent_ref(trans, &ref);
1933 BUG_ON(ret);
1934 btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF, new_bytenr,
1935 blocksize, 0);
1936 ref.skip_qgroup = true;
1937 btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid);
1938 ret = btrfs_inc_extent_ref(trans, &ref);
1939 BUG_ON(ret);
1940
1941 btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, new_bytenr,
1942 blocksize, path->nodes[level]->start);
1943 btrfs_init_tree_ref(&ref, level - 1, src->root_key.objectid);
1944 ref.skip_qgroup = true;
1945 ret = btrfs_free_extent(trans, &ref);
1946 BUG_ON(ret);
1947
1948 btrfs_init_generic_ref(&ref, BTRFS_DROP_DELAYED_REF, old_bytenr,
1949 blocksize, 0);
1950 btrfs_init_tree_ref(&ref, level - 1, dest->root_key.objectid);
1951 ref.skip_qgroup = true;
1952 ret = btrfs_free_extent(trans, &ref);
1953 BUG_ON(ret);
1954
1955 btrfs_unlock_up_safe(path, 0);
1956
1957 ret = level;
1958 break;
1959 }
1960 btrfs_tree_unlock(parent);
1961 free_extent_buffer(parent);
1962 return ret;
1963}
1964
1965
1966
1967
1968static noinline_for_stack
1969int walk_up_reloc_tree(struct btrfs_root *root, struct btrfs_path *path,
1970 int *level)
1971{
1972 struct extent_buffer *eb;
1973 int i;
1974 u64 last_snapshot;
1975 u32 nritems;
1976
1977 last_snapshot = btrfs_root_last_snapshot(&root->root_item);
1978
1979 for (i = 0; i < *level; i++) {
1980 free_extent_buffer(path->nodes[i]);
1981 path->nodes[i] = NULL;
1982 }
1983
1984 for (i = *level; i < BTRFS_MAX_LEVEL && path->nodes[i]; i++) {
1985 eb = path->nodes[i];
1986 nritems = btrfs_header_nritems(eb);
1987 while (path->slots[i] + 1 < nritems) {
1988 path->slots[i]++;
1989 if (btrfs_node_ptr_generation(eb, path->slots[i]) <=
1990 last_snapshot)
1991 continue;
1992
1993 *level = i;
1994 return 0;
1995 }
1996 free_extent_buffer(path->nodes[i]);
1997 path->nodes[i] = NULL;
1998 }
1999 return 1;
2000}
2001
2002
2003
2004
2005static noinline_for_stack
2006int walk_down_reloc_tree(struct btrfs_root *root, struct btrfs_path *path,
2007 int *level)
2008{
2009 struct btrfs_fs_info *fs_info = root->fs_info;
2010 struct extent_buffer *eb = NULL;
2011 int i;
2012 u64 bytenr;
2013 u64 ptr_gen = 0;
2014 u64 last_snapshot;
2015 u32 nritems;
2016
2017 last_snapshot = btrfs_root_last_snapshot(&root->root_item);
2018
2019 for (i = *level; i > 0; i--) {
2020 struct btrfs_key first_key;
2021
2022 eb = path->nodes[i];
2023 nritems = btrfs_header_nritems(eb);
2024 while (path->slots[i] < nritems) {
2025 ptr_gen = btrfs_node_ptr_generation(eb, path->slots[i]);
2026 if (ptr_gen > last_snapshot)
2027 break;
2028 path->slots[i]++;
2029 }
2030 if (path->slots[i] >= nritems) {
2031 if (i == *level)
2032 break;
2033 *level = i + 1;
2034 return 0;
2035 }
2036 if (i == 1) {
2037 *level = i;
2038 return 0;
2039 }
2040
2041 bytenr = btrfs_node_blockptr(eb, path->slots[i]);
2042 btrfs_node_key_to_cpu(eb, &first_key, path->slots[i]);
2043 eb = read_tree_block(fs_info, bytenr, ptr_gen, i - 1,
2044 &first_key);
2045 if (IS_ERR(eb)) {
2046 return PTR_ERR(eb);
2047 } else if (!extent_buffer_uptodate(eb)) {
2048 free_extent_buffer(eb);
2049 return -EIO;
2050 }
2051 BUG_ON(btrfs_header_level(eb) != i - 1);
2052 path->nodes[i - 1] = eb;
2053 path->slots[i - 1] = 0;
2054 }
2055 return 1;
2056}
2057
2058
2059
2060
2061
2062static int invalidate_extent_cache(struct btrfs_root *root,
2063 struct btrfs_key *min_key,
2064 struct btrfs_key *max_key)
2065{
2066 struct btrfs_fs_info *fs_info = root->fs_info;
2067 struct inode *inode = NULL;
2068 u64 objectid;
2069 u64 start, end;
2070 u64 ino;
2071
2072 objectid = min_key->objectid;
2073 while (1) {
2074 cond_resched();
2075 iput(inode);
2076
2077 if (objectid > max_key->objectid)
2078 break;
2079
2080 inode = find_next_inode(root, objectid);
2081 if (!inode)
2082 break;
2083 ino = btrfs_ino(BTRFS_I(inode));
2084
2085 if (ino > max_key->objectid) {
2086 iput(inode);
2087 break;
2088 }
2089
2090 objectid = ino + 1;
2091 if (!S_ISREG(inode->i_mode))
2092 continue;
2093
2094 if (unlikely(min_key->objectid == ino)) {
2095 if (min_key->type > BTRFS_EXTENT_DATA_KEY)
2096 continue;
2097 if (min_key->type < BTRFS_EXTENT_DATA_KEY)
2098 start = 0;
2099 else {
2100 start = min_key->offset;
2101 WARN_ON(!IS_ALIGNED(start, fs_info->sectorsize));
2102 }
2103 } else {
2104 start = 0;
2105 }
2106
2107 if (unlikely(max_key->objectid == ino)) {
2108 if (max_key->type < BTRFS_EXTENT_DATA_KEY)
2109 continue;
2110 if (max_key->type > BTRFS_EXTENT_DATA_KEY) {
2111 end = (u64)-1;
2112 } else {
2113 if (max_key->offset == 0)
2114 continue;
2115 end = max_key->offset;
2116 WARN_ON(!IS_ALIGNED(end, fs_info->sectorsize));
2117 end--;
2118 }
2119 } else {
2120 end = (u64)-1;
2121 }
2122
2123
2124 lock_extent(&BTRFS_I(inode)->io_tree, start, end);
2125 btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 1);
2126 unlock_extent(&BTRFS_I(inode)->io_tree, start, end);
2127 }
2128 return 0;
2129}
2130
2131static int find_next_key(struct btrfs_path *path, int level,
2132 struct btrfs_key *key)
2133
2134{
2135 while (level < BTRFS_MAX_LEVEL) {
2136 if (!path->nodes[level])
2137 break;
2138 if (path->slots[level] + 1 <
2139 btrfs_header_nritems(path->nodes[level])) {
2140 btrfs_node_key_to_cpu(path->nodes[level], key,
2141 path->slots[level] + 1);
2142 return 0;
2143 }
2144 level++;
2145 }
2146 return 1;
2147}
2148
2149
2150
2151
2152static void insert_dirty_subvol(struct btrfs_trans_handle *trans,
2153 struct reloc_control *rc,
2154 struct btrfs_root *root)
2155{
2156 struct btrfs_root *reloc_root = root->reloc_root;
2157 struct btrfs_root_item *reloc_root_item;
2158
2159
2160 ASSERT(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
2161 ASSERT(reloc_root);
2162
2163 reloc_root_item = &reloc_root->root_item;
2164 memset(&reloc_root_item->drop_progress, 0,
2165 sizeof(reloc_root_item->drop_progress));
2166 reloc_root_item->drop_level = 0;
2167 btrfs_set_root_refs(reloc_root_item, 0);
2168 btrfs_update_reloc_root(trans, root);
2169
2170 if (list_empty(&root->reloc_dirty_list)) {
2171 btrfs_grab_fs_root(root);
2172 list_add_tail(&root->reloc_dirty_list, &rc->dirty_subvol_roots);
2173 }
2174}
2175
2176static int clean_dirty_subvols(struct reloc_control *rc)
2177{
2178 struct btrfs_root *root;
2179 struct btrfs_root *next;
2180 int ret = 0;
2181 int ret2;
2182
2183 list_for_each_entry_safe(root, next, &rc->dirty_subvol_roots,
2184 reloc_dirty_list) {
2185 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID) {
2186
2187 struct btrfs_root *reloc_root = root->reloc_root;
2188
2189 clear_bit(BTRFS_ROOT_DEAD_RELOC_TREE, &root->state);
2190 list_del_init(&root->reloc_dirty_list);
2191 root->reloc_root = NULL;
2192 if (reloc_root) {
2193
2194 ret2 = btrfs_drop_snapshot(reloc_root, NULL, 0, 1);
2195 if (ret2 < 0 && !ret)
2196 ret = ret2;
2197 }
2198 btrfs_put_fs_root(root);
2199 } else {
2200
2201 ret2 = btrfs_drop_snapshot(root, NULL, 0, 1);
2202 if (ret2 < 0 && !ret)
2203 ret = ret2;
2204 }
2205 }
2206 return ret;
2207}
2208
2209
2210
2211
2212
2213static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
2214 struct btrfs_root *root)
2215{
2216 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
2217 struct btrfs_key key;
2218 struct btrfs_key next_key;
2219 struct btrfs_trans_handle *trans = NULL;
2220 struct btrfs_root *reloc_root;
2221 struct btrfs_root_item *root_item;
2222 struct btrfs_path *path;
2223 struct extent_buffer *leaf;
2224 int level;
2225 int max_level;
2226 int replaced = 0;
2227 int ret;
2228 int err = 0;
2229 u32 min_reserved;
2230
2231 path = btrfs_alloc_path();
2232 if (!path)
2233 return -ENOMEM;
2234 path->reada = READA_FORWARD;
2235
2236 reloc_root = root->reloc_root;
2237 root_item = &reloc_root->root_item;
2238
2239 if (btrfs_disk_key_objectid(&root_item->drop_progress) == 0) {
2240 level = btrfs_root_level(root_item);
2241 extent_buffer_get(reloc_root->node);
2242 path->nodes[level] = reloc_root->node;
2243 path->slots[level] = 0;
2244 } else {
2245 btrfs_disk_key_to_cpu(&key, &root_item->drop_progress);
2246
2247 level = root_item->drop_level;
2248 BUG_ON(level == 0);
2249 path->lowest_level = level;
2250 ret = btrfs_search_slot(NULL, reloc_root, &key, path, 0, 0);
2251 path->lowest_level = 0;
2252 if (ret < 0) {
2253 btrfs_free_path(path);
2254 return ret;
2255 }
2256
2257 btrfs_node_key_to_cpu(path->nodes[level], &next_key,
2258 path->slots[level]);
2259 WARN_ON(memcmp(&key, &next_key, sizeof(key)));
2260
2261 btrfs_unlock_up_safe(path, 0);
2262 }
2263
2264 min_reserved = fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2;
2265 memset(&next_key, 0, sizeof(next_key));
2266
2267 while (1) {
2268 ret = btrfs_block_rsv_refill(root, rc->block_rsv, min_reserved,
2269 BTRFS_RESERVE_FLUSH_ALL);
2270 if (ret) {
2271 err = ret;
2272 goto out;
2273 }
2274 trans = btrfs_start_transaction(root, 0);
2275 if (IS_ERR(trans)) {
2276 err = PTR_ERR(trans);
2277 trans = NULL;
2278 goto out;
2279 }
2280 trans->block_rsv = rc->block_rsv;
2281
2282 replaced = 0;
2283 max_level = level;
2284
2285 ret = walk_down_reloc_tree(reloc_root, path, &level);
2286 if (ret < 0) {
2287 err = ret;
2288 goto out;
2289 }
2290 if (ret > 0)
2291 break;
2292
2293 if (!find_next_key(path, level, &key) &&
2294 btrfs_comp_cpu_keys(&next_key, &key) >= 0) {
2295 ret = 0;
2296 } else {
2297 ret = replace_path(trans, rc, root, reloc_root, path,
2298 &next_key, level, max_level);
2299 }
2300 if (ret < 0) {
2301 err = ret;
2302 goto out;
2303 }
2304
2305 if (ret > 0) {
2306 level = ret;
2307 btrfs_node_key_to_cpu(path->nodes[level], &key,
2308 path->slots[level]);
2309 replaced = 1;
2310 }
2311
2312 ret = walk_up_reloc_tree(reloc_root, path, &level);
2313 if (ret > 0)
2314 break;
2315
2316 BUG_ON(level == 0);
2317
2318
2319
2320
2321 btrfs_node_key(path->nodes[level], &root_item->drop_progress,
2322 path->slots[level]);
2323 root_item->drop_level = level;
2324
2325 btrfs_end_transaction_throttle(trans);
2326 trans = NULL;
2327
2328 btrfs_btree_balance_dirty(fs_info);
2329
2330 if (replaced && rc->stage == UPDATE_DATA_PTRS)
2331 invalidate_extent_cache(root, &key, &next_key);
2332 }
2333
2334
2335
2336
2337
2338 leaf = btrfs_lock_root_node(root);
2339 ret = btrfs_cow_block(trans, root, leaf, NULL, 0, &leaf);
2340 btrfs_tree_unlock(leaf);
2341 free_extent_buffer(leaf);
2342 if (ret < 0)
2343 err = ret;
2344out:
2345 btrfs_free_path(path);
2346
2347 if (err == 0)
2348 insert_dirty_subvol(trans, rc, root);
2349
2350 if (trans)
2351 btrfs_end_transaction_throttle(trans);
2352
2353 btrfs_btree_balance_dirty(fs_info);
2354
2355 if (replaced && rc->stage == UPDATE_DATA_PTRS)
2356 invalidate_extent_cache(root, &key, &next_key);
2357
2358 return err;
2359}
2360
2361static noinline_for_stack
2362int prepare_to_merge(struct reloc_control *rc, int err)
2363{
2364 struct btrfs_root *root = rc->extent_root;
2365 struct btrfs_fs_info *fs_info = root->fs_info;
2366 struct btrfs_root *reloc_root;
2367 struct btrfs_trans_handle *trans;
2368 LIST_HEAD(reloc_roots);
2369 u64 num_bytes = 0;
2370 int ret;
2371
2372 mutex_lock(&fs_info->reloc_mutex);
2373 rc->merging_rsv_size += fs_info->nodesize * (BTRFS_MAX_LEVEL - 1) * 2;
2374 rc->merging_rsv_size += rc->nodes_relocated * 2;
2375 mutex_unlock(&fs_info->reloc_mutex);
2376
2377again:
2378 if (!err) {
2379 num_bytes = rc->merging_rsv_size;
2380 ret = btrfs_block_rsv_add(root, rc->block_rsv, num_bytes,
2381 BTRFS_RESERVE_FLUSH_ALL);
2382 if (ret)
2383 err = ret;
2384 }
2385
2386 trans = btrfs_join_transaction(rc->extent_root);
2387 if (IS_ERR(trans)) {
2388 if (!err)
2389 btrfs_block_rsv_release(fs_info, rc->block_rsv,
2390 num_bytes);
2391 return PTR_ERR(trans);
2392 }
2393
2394 if (!err) {
2395 if (num_bytes != rc->merging_rsv_size) {
2396 btrfs_end_transaction(trans);
2397 btrfs_block_rsv_release(fs_info, rc->block_rsv,
2398 num_bytes);
2399 goto again;
2400 }
2401 }
2402
2403 rc->merge_reloc_tree = 1;
2404
2405 while (!list_empty(&rc->reloc_roots)) {
2406 reloc_root = list_entry(rc->reloc_roots.next,
2407 struct btrfs_root, root_list);
2408 list_del_init(&reloc_root->root_list);
2409
2410 root = read_fs_root(fs_info, reloc_root->root_key.offset);
2411 BUG_ON(IS_ERR(root));
2412 BUG_ON(root->reloc_root != reloc_root);
2413
2414
2415
2416
2417
2418 if (!err)
2419 btrfs_set_root_refs(&reloc_root->root_item, 1);
2420 btrfs_update_reloc_root(trans, root);
2421
2422 list_add(&reloc_root->root_list, &reloc_roots);
2423 }
2424
2425 list_splice(&reloc_roots, &rc->reloc_roots);
2426
2427 if (!err)
2428 btrfs_commit_transaction(trans);
2429 else
2430 btrfs_end_transaction(trans);
2431 return err;
2432}
2433
2434static noinline_for_stack
2435void free_reloc_roots(struct list_head *list)
2436{
2437 struct btrfs_root *reloc_root;
2438
2439 while (!list_empty(list)) {
2440 reloc_root = list_entry(list->next, struct btrfs_root,
2441 root_list);
2442 __del_reloc_root(reloc_root);
2443 free_extent_buffer(reloc_root->node);
2444 free_extent_buffer(reloc_root->commit_root);
2445 reloc_root->node = NULL;
2446 reloc_root->commit_root = NULL;
2447 }
2448}
2449
2450static noinline_for_stack
2451void merge_reloc_roots(struct reloc_control *rc)
2452{
2453 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
2454 struct btrfs_root *root;
2455 struct btrfs_root *reloc_root;
2456 LIST_HEAD(reloc_roots);
2457 int found = 0;
2458 int ret = 0;
2459again:
2460 root = rc->extent_root;
2461
2462
2463
2464
2465
2466
2467
2468 mutex_lock(&fs_info->reloc_mutex);
2469 list_splice_init(&rc->reloc_roots, &reloc_roots);
2470 mutex_unlock(&fs_info->reloc_mutex);
2471
2472 while (!list_empty(&reloc_roots)) {
2473 found = 1;
2474 reloc_root = list_entry(reloc_roots.next,
2475 struct btrfs_root, root_list);
2476
2477 if (btrfs_root_refs(&reloc_root->root_item) > 0) {
2478 root = read_fs_root(fs_info,
2479 reloc_root->root_key.offset);
2480 BUG_ON(IS_ERR(root));
2481 BUG_ON(root->reloc_root != reloc_root);
2482
2483 ret = merge_reloc_root(rc, root);
2484 if (ret) {
2485 if (list_empty(&reloc_root->root_list))
2486 list_add_tail(&reloc_root->root_list,
2487 &reloc_roots);
2488 goto out;
2489 }
2490 } else {
2491 list_del_init(&reloc_root->root_list);
2492
2493 list_add_tail(&reloc_root->reloc_dirty_list,
2494 &rc->dirty_subvol_roots);
2495 }
2496 }
2497
2498 if (found) {
2499 found = 0;
2500 goto again;
2501 }
2502out:
2503 if (ret) {
2504 btrfs_handle_fs_error(fs_info, ret, NULL);
2505 if (!list_empty(&reloc_roots))
2506 free_reloc_roots(&reloc_roots);
2507
2508
2509 mutex_lock(&fs_info->reloc_mutex);
2510 list_splice_init(&rc->reloc_roots, &reloc_roots);
2511 mutex_unlock(&fs_info->reloc_mutex);
2512 if (!list_empty(&reloc_roots))
2513 free_reloc_roots(&reloc_roots);
2514 }
2515
2516 BUG_ON(!RB_EMPTY_ROOT(&rc->reloc_root_tree.rb_root));
2517}
2518
2519static void free_block_list(struct rb_root *blocks)
2520{
2521 struct tree_block *block;
2522 struct rb_node *rb_node;
2523 while ((rb_node = rb_first(blocks))) {
2524 block = rb_entry(rb_node, struct tree_block, rb_node);
2525 rb_erase(rb_node, blocks);
2526 kfree(block);
2527 }
2528}
2529
2530static int record_reloc_root_in_trans(struct btrfs_trans_handle *trans,
2531 struct btrfs_root *reloc_root)
2532{
2533 struct btrfs_fs_info *fs_info = reloc_root->fs_info;
2534 struct btrfs_root *root;
2535
2536 if (reloc_root->last_trans == trans->transid)
2537 return 0;
2538
2539 root = read_fs_root(fs_info, reloc_root->root_key.offset);
2540 BUG_ON(IS_ERR(root));
2541 BUG_ON(root->reloc_root != reloc_root);
2542
2543 return btrfs_record_root_in_trans(trans, root);
2544}
2545
2546static noinline_for_stack
2547struct btrfs_root *select_reloc_root(struct btrfs_trans_handle *trans,
2548 struct reloc_control *rc,
2549 struct backref_node *node,
2550 struct backref_edge *edges[])
2551{
2552 struct backref_node *next;
2553 struct btrfs_root *root;
2554 int index = 0;
2555
2556 next = node;
2557 while (1) {
2558 cond_resched();
2559 next = walk_up_backref(next, edges, &index);
2560 root = next->root;
2561 BUG_ON(!root);
2562 BUG_ON(!test_bit(BTRFS_ROOT_REF_COWS, &root->state));
2563
2564 if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
2565 record_reloc_root_in_trans(trans, root);
2566 break;
2567 }
2568
2569 btrfs_record_root_in_trans(trans, root);
2570 root = root->reloc_root;
2571
2572 if (next->new_bytenr != root->node->start) {
2573 BUG_ON(next->new_bytenr);
2574 BUG_ON(!list_empty(&next->list));
2575 next->new_bytenr = root->node->start;
2576 next->root = root;
2577 list_add_tail(&next->list,
2578 &rc->backref_cache.changed);
2579 __mark_block_processed(rc, next);
2580 break;
2581 }
2582
2583 WARN_ON(1);
2584 root = NULL;
2585 next = walk_down_backref(edges, &index);
2586 if (!next || next->level <= node->level)
2587 break;
2588 }
2589 if (!root)
2590 return NULL;
2591
2592 next = node;
2593
2594 while (1) {
2595 rc->backref_cache.path[next->level] = next;
2596 if (--index < 0)
2597 break;
2598 next = edges[index]->node[UPPER];
2599 }
2600 return root;
2601}
2602
2603
2604
2605
2606
2607
2608
2609static noinline_for_stack
2610struct btrfs_root *select_one_root(struct backref_node *node)
2611{
2612 struct backref_node *next;
2613 struct btrfs_root *root;
2614 struct btrfs_root *fs_root = NULL;
2615 struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
2616 int index = 0;
2617
2618 next = node;
2619 while (1) {
2620 cond_resched();
2621 next = walk_up_backref(next, edges, &index);
2622 root = next->root;
2623 BUG_ON(!root);
2624
2625
2626 if (!test_bit(BTRFS_ROOT_REF_COWS, &root->state))
2627 return root;
2628
2629 if (root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID)
2630 fs_root = root;
2631
2632 if (next != node)
2633 return NULL;
2634
2635 next = walk_down_backref(edges, &index);
2636 if (!next || next->level <= node->level)
2637 break;
2638 }
2639
2640 if (!fs_root)
2641 return ERR_PTR(-ENOENT);
2642 return fs_root;
2643}
2644
2645static noinline_for_stack
2646u64 calcu_metadata_size(struct reloc_control *rc,
2647 struct backref_node *node, int reserve)
2648{
2649 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
2650 struct backref_node *next = node;
2651 struct backref_edge *edge;
2652 struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
2653 u64 num_bytes = 0;
2654 int index = 0;
2655
2656 BUG_ON(reserve && node->processed);
2657
2658 while (next) {
2659 cond_resched();
2660 while (1) {
2661 if (next->processed && (reserve || next != node))
2662 break;
2663
2664 num_bytes += fs_info->nodesize;
2665
2666 if (list_empty(&next->upper))
2667 break;
2668
2669 edge = list_entry(next->upper.next,
2670 struct backref_edge, list[LOWER]);
2671 edges[index++] = edge;
2672 next = edge->node[UPPER];
2673 }
2674 next = walk_down_backref(edges, &index);
2675 }
2676 return num_bytes;
2677}
2678
2679static int reserve_metadata_space(struct btrfs_trans_handle *trans,
2680 struct reloc_control *rc,
2681 struct backref_node *node)
2682{
2683 struct btrfs_root *root = rc->extent_root;
2684 struct btrfs_fs_info *fs_info = root->fs_info;
2685 u64 num_bytes;
2686 int ret;
2687 u64 tmp;
2688
2689 num_bytes = calcu_metadata_size(rc, node, 1) * 2;
2690
2691 trans->block_rsv = rc->block_rsv;
2692 rc->reserved_bytes += num_bytes;
2693
2694
2695
2696
2697
2698
2699 ret = btrfs_block_rsv_refill(root, rc->block_rsv, num_bytes,
2700 BTRFS_RESERVE_FLUSH_LIMIT);
2701 if (ret) {
2702 tmp = fs_info->nodesize * RELOCATION_RESERVED_NODES;
2703 while (tmp <= rc->reserved_bytes)
2704 tmp <<= 1;
2705
2706
2707
2708
2709
2710
2711
2712 rc->block_rsv->size = tmp + fs_info->nodesize *
2713 RELOCATION_RESERVED_NODES;
2714 return -EAGAIN;
2715 }
2716
2717 return 0;
2718}
2719
2720
2721
2722
2723
2724
2725
2726
2727static int do_relocation(struct btrfs_trans_handle *trans,
2728 struct reloc_control *rc,
2729 struct backref_node *node,
2730 struct btrfs_key *key,
2731 struct btrfs_path *path, int lowest)
2732{
2733 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
2734 struct backref_node *upper;
2735 struct backref_edge *edge;
2736 struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
2737 struct btrfs_root *root;
2738 struct extent_buffer *eb;
2739 u32 blocksize;
2740 u64 bytenr;
2741 u64 generation;
2742 int slot;
2743 int ret;
2744 int err = 0;
2745
2746 BUG_ON(lowest && node->eb);
2747
2748 path->lowest_level = node->level + 1;
2749 rc->backref_cache.path[node->level] = node;
2750 list_for_each_entry(edge, &node->upper, list[LOWER]) {
2751 struct btrfs_key first_key;
2752 struct btrfs_ref ref = { 0 };
2753
2754 cond_resched();
2755
2756 upper = edge->node[UPPER];
2757 root = select_reloc_root(trans, rc, upper, edges);
2758 BUG_ON(!root);
2759
2760 if (upper->eb && !upper->locked) {
2761 if (!lowest) {
2762 ret = btrfs_bin_search(upper->eb, key,
2763 upper->level, &slot);
2764 if (ret < 0) {
2765 err = ret;
2766 goto next;
2767 }
2768 BUG_ON(ret);
2769 bytenr = btrfs_node_blockptr(upper->eb, slot);
2770 if (node->eb->start == bytenr)
2771 goto next;
2772 }
2773 drop_node_buffer(upper);
2774 }
2775
2776 if (!upper->eb) {
2777 ret = btrfs_search_slot(trans, root, key, path, 0, 1);
2778 if (ret) {
2779 if (ret < 0)
2780 err = ret;
2781 else
2782 err = -ENOENT;
2783
2784 btrfs_release_path(path);
2785 break;
2786 }
2787
2788 if (!upper->eb) {
2789 upper->eb = path->nodes[upper->level];
2790 path->nodes[upper->level] = NULL;
2791 } else {
2792 BUG_ON(upper->eb != path->nodes[upper->level]);
2793 }
2794
2795 upper->locked = 1;
2796 path->locks[upper->level] = 0;
2797
2798 slot = path->slots[upper->level];
2799 btrfs_release_path(path);
2800 } else {
2801 ret = btrfs_bin_search(upper->eb, key, upper->level,
2802 &slot);
2803 if (ret < 0) {
2804 err = ret;
2805 goto next;
2806 }
2807 BUG_ON(ret);
2808 }
2809
2810 bytenr = btrfs_node_blockptr(upper->eb, slot);
2811 if (lowest) {
2812 if (bytenr != node->bytenr) {
2813 btrfs_err(root->fs_info,
2814 "lowest leaf/node mismatch: bytenr %llu node->bytenr %llu slot %d upper %llu",
2815 bytenr, node->bytenr, slot,
2816 upper->eb->start);
2817 err = -EIO;
2818 goto next;
2819 }
2820 } else {
2821 if (node->eb->start == bytenr)
2822 goto next;
2823 }
2824
2825 blocksize = root->fs_info->nodesize;
2826 generation = btrfs_node_ptr_generation(upper->eb, slot);
2827 btrfs_node_key_to_cpu(upper->eb, &first_key, slot);
2828 eb = read_tree_block(fs_info, bytenr, generation,
2829 upper->level - 1, &first_key);
2830 if (IS_ERR(eb)) {
2831 err = PTR_ERR(eb);
2832 goto next;
2833 } else if (!extent_buffer_uptodate(eb)) {
2834 free_extent_buffer(eb);
2835 err = -EIO;
2836 goto next;
2837 }
2838 btrfs_tree_lock(eb);
2839 btrfs_set_lock_blocking_write(eb);
2840
2841 if (!node->eb) {
2842 ret = btrfs_cow_block(trans, root, eb, upper->eb,
2843 slot, &eb);
2844 btrfs_tree_unlock(eb);
2845 free_extent_buffer(eb);
2846 if (ret < 0) {
2847 err = ret;
2848 goto next;
2849 }
2850 BUG_ON(node->eb != eb);
2851 } else {
2852 btrfs_set_node_blockptr(upper->eb, slot,
2853 node->eb->start);
2854 btrfs_set_node_ptr_generation(upper->eb, slot,
2855 trans->transid);
2856 btrfs_mark_buffer_dirty(upper->eb);
2857
2858 btrfs_init_generic_ref(&ref, BTRFS_ADD_DELAYED_REF,
2859 node->eb->start, blocksize,
2860 upper->eb->start);
2861 ref.real_root = root->root_key.objectid;
2862 btrfs_init_tree_ref(&ref, node->level,
2863 btrfs_header_owner(upper->eb));
2864 ret = btrfs_inc_extent_ref(trans, &ref);
2865 BUG_ON(ret);
2866
2867 ret = btrfs_drop_subtree(trans, root, eb, upper->eb);
2868 BUG_ON(ret);
2869 }
2870next:
2871 if (!upper->pending)
2872 drop_node_buffer(upper);
2873 else
2874 unlock_node_buffer(upper);
2875 if (err)
2876 break;
2877 }
2878
2879 if (!err && node->pending) {
2880 drop_node_buffer(node);
2881 list_move_tail(&node->list, &rc->backref_cache.changed);
2882 node->pending = 0;
2883 }
2884
2885 path->lowest_level = 0;
2886 BUG_ON(err == -ENOSPC);
2887 return err;
2888}
2889
2890static int link_to_upper(struct btrfs_trans_handle *trans,
2891 struct reloc_control *rc,
2892 struct backref_node *node,
2893 struct btrfs_path *path)
2894{
2895 struct btrfs_key key;
2896
2897 btrfs_node_key_to_cpu(node->eb, &key, 0);
2898 return do_relocation(trans, rc, node, &key, path, 0);
2899}
2900
2901static int finish_pending_nodes(struct btrfs_trans_handle *trans,
2902 struct reloc_control *rc,
2903 struct btrfs_path *path, int err)
2904{
2905 LIST_HEAD(list);
2906 struct backref_cache *cache = &rc->backref_cache;
2907 struct backref_node *node;
2908 int level;
2909 int ret;
2910
2911 for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
2912 while (!list_empty(&cache->pending[level])) {
2913 node = list_entry(cache->pending[level].next,
2914 struct backref_node, list);
2915 list_move_tail(&node->list, &list);
2916 BUG_ON(!node->pending);
2917
2918 if (!err) {
2919 ret = link_to_upper(trans, rc, node, path);
2920 if (ret < 0)
2921 err = ret;
2922 }
2923 }
2924 list_splice_init(&list, &cache->pending[level]);
2925 }
2926 return err;
2927}
2928
2929static void mark_block_processed(struct reloc_control *rc,
2930 u64 bytenr, u32 blocksize)
2931{
2932 set_extent_bits(&rc->processed_blocks, bytenr, bytenr + blocksize - 1,
2933 EXTENT_DIRTY);
2934}
2935
2936static void __mark_block_processed(struct reloc_control *rc,
2937 struct backref_node *node)
2938{
2939 u32 blocksize;
2940 if (node->level == 0 ||
2941 in_block_group(node->bytenr, rc->block_group)) {
2942 blocksize = rc->extent_root->fs_info->nodesize;
2943 mark_block_processed(rc, node->bytenr, blocksize);
2944 }
2945 node->processed = 1;
2946}
2947
2948
2949
2950
2951
2952static void update_processed_blocks(struct reloc_control *rc,
2953 struct backref_node *node)
2954{
2955 struct backref_node *next = node;
2956 struct backref_edge *edge;
2957 struct backref_edge *edges[BTRFS_MAX_LEVEL - 1];
2958 int index = 0;
2959
2960 while (next) {
2961 cond_resched();
2962 while (1) {
2963 if (next->processed)
2964 break;
2965
2966 __mark_block_processed(rc, next);
2967
2968 if (list_empty(&next->upper))
2969 break;
2970
2971 edge = list_entry(next->upper.next,
2972 struct backref_edge, list[LOWER]);
2973 edges[index++] = edge;
2974 next = edge->node[UPPER];
2975 }
2976 next = walk_down_backref(edges, &index);
2977 }
2978}
2979
2980static int tree_block_processed(u64 bytenr, struct reloc_control *rc)
2981{
2982 u32 blocksize = rc->extent_root->fs_info->nodesize;
2983
2984 if (test_range_bit(&rc->processed_blocks, bytenr,
2985 bytenr + blocksize - 1, EXTENT_DIRTY, 1, NULL))
2986 return 1;
2987 return 0;
2988}
2989
2990static int get_tree_block_key(struct btrfs_fs_info *fs_info,
2991 struct tree_block *block)
2992{
2993 struct extent_buffer *eb;
2994
2995 BUG_ON(block->key_ready);
2996 eb = read_tree_block(fs_info, block->bytenr, block->key.offset,
2997 block->level, NULL);
2998 if (IS_ERR(eb)) {
2999 return PTR_ERR(eb);
3000 } else if (!extent_buffer_uptodate(eb)) {
3001 free_extent_buffer(eb);
3002 return -EIO;
3003 }
3004 if (block->level == 0)
3005 btrfs_item_key_to_cpu(eb, &block->key, 0);
3006 else
3007 btrfs_node_key_to_cpu(eb, &block->key, 0);
3008 free_extent_buffer(eb);
3009 block->key_ready = 1;
3010 return 0;
3011}
3012
3013
3014
3015
3016static int relocate_tree_block(struct btrfs_trans_handle *trans,
3017 struct reloc_control *rc,
3018 struct backref_node *node,
3019 struct btrfs_key *key,
3020 struct btrfs_path *path)
3021{
3022 struct btrfs_root *root;
3023 int ret = 0;
3024
3025 if (!node)
3026 return 0;
3027
3028 BUG_ON(node->processed);
3029 root = select_one_root(node);
3030 if (root == ERR_PTR(-ENOENT)) {
3031 update_processed_blocks(rc, node);
3032 goto out;
3033 }
3034
3035 if (!root || test_bit(BTRFS_ROOT_REF_COWS, &root->state)) {
3036 ret = reserve_metadata_space(trans, rc, node);
3037 if (ret)
3038 goto out;
3039 }
3040
3041 if (root) {
3042 if (test_bit(BTRFS_ROOT_REF_COWS, &root->state)) {
3043 BUG_ON(node->new_bytenr);
3044 BUG_ON(!list_empty(&node->list));
3045 btrfs_record_root_in_trans(trans, root);
3046 root = root->reloc_root;
3047 node->new_bytenr = root->node->start;
3048 node->root = root;
3049 list_add_tail(&node->list, &rc->backref_cache.changed);
3050 } else {
3051 path->lowest_level = node->level;
3052 ret = btrfs_search_slot(trans, root, key, path, 0, 1);
3053 btrfs_release_path(path);
3054 if (ret > 0)
3055 ret = 0;
3056 }
3057 if (!ret)
3058 update_processed_blocks(rc, node);
3059 } else {
3060 ret = do_relocation(trans, rc, node, key, path, 1);
3061 }
3062out:
3063 if (ret || node->level == 0 || node->cowonly)
3064 remove_backref_node(&rc->backref_cache, node);
3065 return ret;
3066}
3067
3068
3069
3070
3071static noinline_for_stack
3072int relocate_tree_blocks(struct btrfs_trans_handle *trans,
3073 struct reloc_control *rc, struct rb_root *blocks)
3074{
3075 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
3076 struct backref_node *node;
3077 struct btrfs_path *path;
3078 struct tree_block *block;
3079 struct tree_block *next;
3080 int ret;
3081 int err = 0;
3082
3083 path = btrfs_alloc_path();
3084 if (!path) {
3085 err = -ENOMEM;
3086 goto out_free_blocks;
3087 }
3088
3089
3090 rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) {
3091 if (!block->key_ready)
3092 readahead_tree_block(fs_info, block->bytenr);
3093 }
3094
3095
3096 rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) {
3097 if (!block->key_ready) {
3098 err = get_tree_block_key(fs_info, block);
3099 if (err)
3100 goto out_free_path;
3101 }
3102 }
3103
3104
3105 rbtree_postorder_for_each_entry_safe(block, next, blocks, rb_node) {
3106 node = build_backref_tree(rc, &block->key,
3107 block->level, block->bytenr);
3108 if (IS_ERR(node)) {
3109 err = PTR_ERR(node);
3110 goto out;
3111 }
3112
3113 ret = relocate_tree_block(trans, rc, node, &block->key,
3114 path);
3115 if (ret < 0) {
3116 if (ret != -EAGAIN || &block->rb_node == rb_first(blocks))
3117 err = ret;
3118 goto out;
3119 }
3120 }
3121out:
3122 err = finish_pending_nodes(trans, rc, path, err);
3123
3124out_free_path:
3125 btrfs_free_path(path);
3126out_free_blocks:
3127 free_block_list(blocks);
3128 return err;
3129}
3130
3131static noinline_for_stack
3132int prealloc_file_extent_cluster(struct inode *inode,
3133 struct file_extent_cluster *cluster)
3134{
3135 u64 alloc_hint = 0;
3136 u64 start;
3137 u64 end;
3138 u64 offset = BTRFS_I(inode)->index_cnt;
3139 u64 num_bytes;
3140 int nr = 0;
3141 int ret = 0;
3142 u64 prealloc_start = cluster->start - offset;
3143 u64 prealloc_end = cluster->end - offset;
3144 u64 cur_offset;
3145 struct extent_changeset *data_reserved = NULL;
3146
3147 BUG_ON(cluster->start != cluster->boundary[0]);
3148 inode_lock(inode);
3149
3150 ret = btrfs_check_data_free_space(inode, &data_reserved, prealloc_start,
3151 prealloc_end + 1 - prealloc_start);
3152 if (ret)
3153 goto out;
3154
3155 cur_offset = prealloc_start;
3156 while (nr < cluster->nr) {
3157 start = cluster->boundary[nr] - offset;
3158 if (nr + 1 < cluster->nr)
3159 end = cluster->boundary[nr + 1] - 1 - offset;
3160 else
3161 end = cluster->end - offset;
3162
3163 lock_extent(&BTRFS_I(inode)->io_tree, start, end);
3164 num_bytes = end + 1 - start;
3165 if (cur_offset < start)
3166 btrfs_free_reserved_data_space(inode, data_reserved,
3167 cur_offset, start - cur_offset);
3168 ret = btrfs_prealloc_file_range(inode, 0, start,
3169 num_bytes, num_bytes,
3170 end + 1, &alloc_hint);
3171 cur_offset = end + 1;
3172 unlock_extent(&BTRFS_I(inode)->io_tree, start, end);
3173 if (ret)
3174 break;
3175 nr++;
3176 }
3177 if (cur_offset < prealloc_end)
3178 btrfs_free_reserved_data_space(inode, data_reserved,
3179 cur_offset, prealloc_end + 1 - cur_offset);
3180out:
3181 inode_unlock(inode);
3182 extent_changeset_free(data_reserved);
3183 return ret;
3184}
3185
3186static noinline_for_stack
3187int setup_extent_mapping(struct inode *inode, u64 start, u64 end,
3188 u64 block_start)
3189{
3190 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3191 struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree;
3192 struct extent_map *em;
3193 int ret = 0;
3194
3195 em = alloc_extent_map();
3196 if (!em)
3197 return -ENOMEM;
3198
3199 em->start = start;
3200 em->len = end + 1 - start;
3201 em->block_len = em->len;
3202 em->block_start = block_start;
3203 em->bdev = fs_info->fs_devices->latest_bdev;
3204 set_bit(EXTENT_FLAG_PINNED, &em->flags);
3205
3206 lock_extent(&BTRFS_I(inode)->io_tree, start, end);
3207 while (1) {
3208 write_lock(&em_tree->lock);
3209 ret = add_extent_mapping(em_tree, em, 0);
3210 write_unlock(&em_tree->lock);
3211 if (ret != -EEXIST) {
3212 free_extent_map(em);
3213 break;
3214 }
3215 btrfs_drop_extent_cache(BTRFS_I(inode), start, end, 0);
3216 }
3217 unlock_extent(&BTRFS_I(inode)->io_tree, start, end);
3218 return ret;
3219}
3220
3221static int relocate_file_extent_cluster(struct inode *inode,
3222 struct file_extent_cluster *cluster)
3223{
3224 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
3225 u64 page_start;
3226 u64 page_end;
3227 u64 offset = BTRFS_I(inode)->index_cnt;
3228 unsigned long index;
3229 unsigned long last_index;
3230 struct page *page;
3231 struct file_ra_state *ra;
3232 gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
3233 int nr = 0;
3234 int ret = 0;
3235
3236 if (!cluster->nr)
3237 return 0;
3238
3239 ra = kzalloc(sizeof(*ra), GFP_NOFS);
3240 if (!ra)
3241 return -ENOMEM;
3242
3243 ret = prealloc_file_extent_cluster(inode, cluster);
3244 if (ret)
3245 goto out;
3246
3247 file_ra_state_init(ra, inode->i_mapping);
3248
3249 ret = setup_extent_mapping(inode, cluster->start - offset,
3250 cluster->end - offset, cluster->start);
3251 if (ret)
3252 goto out;
3253
3254 index = (cluster->start - offset) >> PAGE_SHIFT;
3255 last_index = (cluster->end - offset) >> PAGE_SHIFT;
3256 while (index <= last_index) {
3257 ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode),
3258 PAGE_SIZE);
3259 if (ret)
3260 goto out;
3261
3262 page = find_lock_page(inode->i_mapping, index);
3263 if (!page) {
3264 page_cache_sync_readahead(inode->i_mapping,
3265 ra, NULL, index,
3266 last_index + 1 - index);
3267 page = find_or_create_page(inode->i_mapping, index,
3268 mask);
3269 if (!page) {
3270 btrfs_delalloc_release_metadata(BTRFS_I(inode),
3271 PAGE_SIZE, true);
3272 ret = -ENOMEM;
3273 goto out;
3274 }
3275 }
3276
3277 if (PageReadahead(page)) {
3278 page_cache_async_readahead(inode->i_mapping,
3279 ra, NULL, page, index,
3280 last_index + 1 - index);
3281 }
3282
3283 if (!PageUptodate(page)) {
3284 btrfs_readpage(NULL, page);
3285 lock_page(page);
3286 if (!PageUptodate(page)) {
3287 unlock_page(page);
3288 put_page(page);
3289 btrfs_delalloc_release_metadata(BTRFS_I(inode),
3290 PAGE_SIZE, true);
3291 btrfs_delalloc_release_extents(BTRFS_I(inode),
3292 PAGE_SIZE, true);
3293 ret = -EIO;
3294 goto out;
3295 }
3296 }
3297
3298 page_start = page_offset(page);
3299 page_end = page_start + PAGE_SIZE - 1;
3300
3301 lock_extent(&BTRFS_I(inode)->io_tree, page_start, page_end);
3302
3303 set_page_extent_mapped(page);
3304
3305 if (nr < cluster->nr &&
3306 page_start + offset == cluster->boundary[nr]) {
3307 set_extent_bits(&BTRFS_I(inode)->io_tree,
3308 page_start, page_end,
3309 EXTENT_BOUNDARY);
3310 nr++;
3311 }
3312
3313 ret = btrfs_set_extent_delalloc(inode, page_start, page_end, 0,
3314 NULL, 0);
3315 if (ret) {
3316 unlock_page(page);
3317 put_page(page);
3318 btrfs_delalloc_release_metadata(BTRFS_I(inode),
3319 PAGE_SIZE, true);
3320 btrfs_delalloc_release_extents(BTRFS_I(inode),
3321 PAGE_SIZE, true);
3322
3323 clear_extent_bits(&BTRFS_I(inode)->io_tree,
3324 page_start, page_end,
3325 EXTENT_LOCKED | EXTENT_BOUNDARY);
3326 goto out;
3327
3328 }
3329 set_page_dirty(page);
3330
3331 unlock_extent(&BTRFS_I(inode)->io_tree,
3332 page_start, page_end);
3333 unlock_page(page);
3334 put_page(page);
3335
3336 index++;
3337 btrfs_delalloc_release_extents(BTRFS_I(inode), PAGE_SIZE,
3338 false);
3339 balance_dirty_pages_ratelimited(inode->i_mapping);
3340 btrfs_throttle(fs_info);
3341 }
3342 WARN_ON(nr != cluster->nr);
3343out:
3344 kfree(ra);
3345 return ret;
3346}
3347
3348static noinline_for_stack
3349int relocate_data_extent(struct inode *inode, struct btrfs_key *extent_key,
3350 struct file_extent_cluster *cluster)
3351{
3352 int ret;
3353
3354 if (cluster->nr > 0 && extent_key->objectid != cluster->end + 1) {
3355 ret = relocate_file_extent_cluster(inode, cluster);
3356 if (ret)
3357 return ret;
3358 cluster->nr = 0;
3359 }
3360
3361 if (!cluster->nr)
3362 cluster->start = extent_key->objectid;
3363 else
3364 BUG_ON(cluster->nr >= MAX_EXTENTS);
3365 cluster->end = extent_key->objectid + extent_key->offset - 1;
3366 cluster->boundary[cluster->nr] = extent_key->objectid;
3367 cluster->nr++;
3368
3369 if (cluster->nr >= MAX_EXTENTS) {
3370 ret = relocate_file_extent_cluster(inode, cluster);
3371 if (ret)
3372 return ret;
3373 cluster->nr = 0;
3374 }
3375 return 0;
3376}
3377
3378
3379
3380
3381
3382static int add_tree_block(struct reloc_control *rc,
3383 struct btrfs_key *extent_key,
3384 struct btrfs_path *path,
3385 struct rb_root *blocks)
3386{
3387 struct extent_buffer *eb;
3388 struct btrfs_extent_item *ei;
3389 struct btrfs_tree_block_info *bi;
3390 struct tree_block *block;
3391 struct rb_node *rb_node;
3392 u32 item_size;
3393 int level = -1;
3394 u64 generation;
3395
3396 eb = path->nodes[0];
3397 item_size = btrfs_item_size_nr(eb, path->slots[0]);
3398
3399 if (extent_key->type == BTRFS_METADATA_ITEM_KEY ||
3400 item_size >= sizeof(*ei) + sizeof(*bi)) {
3401 ei = btrfs_item_ptr(eb, path->slots[0],
3402 struct btrfs_extent_item);
3403 if (extent_key->type == BTRFS_EXTENT_ITEM_KEY) {
3404 bi = (struct btrfs_tree_block_info *)(ei + 1);
3405 level = btrfs_tree_block_level(eb, bi);
3406 } else {
3407 level = (int)extent_key->offset;
3408 }
3409 generation = btrfs_extent_generation(eb, ei);
3410 } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) {
3411 btrfs_print_v0_err(eb->fs_info);
3412 btrfs_handle_fs_error(eb->fs_info, -EINVAL, NULL);
3413 return -EINVAL;
3414 } else {
3415 BUG();
3416 }
3417
3418 btrfs_release_path(path);
3419
3420 BUG_ON(level == -1);
3421
3422 block = kmalloc(sizeof(*block), GFP_NOFS);
3423 if (!block)
3424 return -ENOMEM;
3425
3426 block->bytenr = extent_key->objectid;
3427 block->key.objectid = rc->extent_root->fs_info->nodesize;
3428 block->key.offset = generation;
3429 block->level = level;
3430 block->key_ready = 0;
3431
3432 rb_node = tree_insert(blocks, block->bytenr, &block->rb_node);
3433 if (rb_node)
3434 backref_tree_panic(rb_node, -EEXIST, block->bytenr);
3435
3436 return 0;
3437}
3438
3439
3440
3441
3442static int __add_tree_block(struct reloc_control *rc,
3443 u64 bytenr, u32 blocksize,
3444 struct rb_root *blocks)
3445{
3446 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
3447 struct btrfs_path *path;
3448 struct btrfs_key key;
3449 int ret;
3450 bool skinny = btrfs_fs_incompat(fs_info, SKINNY_METADATA);
3451
3452 if (tree_block_processed(bytenr, rc))
3453 return 0;
3454
3455 if (tree_search(blocks, bytenr))
3456 return 0;
3457
3458 path = btrfs_alloc_path();
3459 if (!path)
3460 return -ENOMEM;
3461again:
3462 key.objectid = bytenr;
3463 if (skinny) {
3464 key.type = BTRFS_METADATA_ITEM_KEY;
3465 key.offset = (u64)-1;
3466 } else {
3467 key.type = BTRFS_EXTENT_ITEM_KEY;
3468 key.offset = blocksize;
3469 }
3470
3471 path->search_commit_root = 1;
3472 path->skip_locking = 1;
3473 ret = btrfs_search_slot(NULL, rc->extent_root, &key, path, 0, 0);
3474 if (ret < 0)
3475 goto out;
3476
3477 if (ret > 0 && skinny) {
3478 if (path->slots[0]) {
3479 path->slots[0]--;
3480 btrfs_item_key_to_cpu(path->nodes[0], &key,
3481 path->slots[0]);
3482 if (key.objectid == bytenr &&
3483 (key.type == BTRFS_METADATA_ITEM_KEY ||
3484 (key.type == BTRFS_EXTENT_ITEM_KEY &&
3485 key.offset == blocksize)))
3486 ret = 0;
3487 }
3488
3489 if (ret) {
3490 skinny = false;
3491 btrfs_release_path(path);
3492 goto again;
3493 }
3494 }
3495 if (ret) {
3496 ASSERT(ret == 1);
3497 btrfs_print_leaf(path->nodes[0]);
3498 btrfs_err(fs_info,
3499 "tree block extent item (%llu) is not found in extent tree",
3500 bytenr);
3501 WARN_ON(1);
3502 ret = -EINVAL;
3503 goto out;
3504 }
3505
3506 ret = add_tree_block(rc, &key, path, blocks);
3507out:
3508 btrfs_free_path(path);
3509 return ret;
3510}
3511
3512
3513
3514
3515static int block_use_full_backref(struct reloc_control *rc,
3516 struct extent_buffer *eb)
3517{
3518 u64 flags;
3519 int ret;
3520
3521 if (btrfs_header_flag(eb, BTRFS_HEADER_FLAG_RELOC) ||
3522 btrfs_header_backref_rev(eb) < BTRFS_MIXED_BACKREF_REV)
3523 return 1;
3524
3525 ret = btrfs_lookup_extent_info(NULL, rc->extent_root->fs_info,
3526 eb->start, btrfs_header_level(eb), 1,
3527 NULL, &flags);
3528 BUG_ON(ret);
3529
3530 if (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF)
3531 ret = 1;
3532 else
3533 ret = 0;
3534 return ret;
3535}
3536
3537static int delete_block_group_cache(struct btrfs_fs_info *fs_info,
3538 struct btrfs_block_group_cache *block_group,
3539 struct inode *inode,
3540 u64 ino)
3541{
3542 struct btrfs_key key;
3543 struct btrfs_root *root = fs_info->tree_root;
3544 struct btrfs_trans_handle *trans;
3545 int ret = 0;
3546
3547 if (inode)
3548 goto truncate;
3549
3550 key.objectid = ino;
3551 key.type = BTRFS_INODE_ITEM_KEY;
3552 key.offset = 0;
3553
3554 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
3555 if (IS_ERR(inode))
3556 return -ENOENT;
3557
3558truncate:
3559 ret = btrfs_check_trunc_cache_free_space(fs_info,
3560 &fs_info->global_block_rsv);
3561 if (ret)
3562 goto out;
3563
3564 trans = btrfs_join_transaction(root);
3565 if (IS_ERR(trans)) {
3566 ret = PTR_ERR(trans);
3567 goto out;
3568 }
3569
3570 ret = btrfs_truncate_free_space_cache(trans, block_group, inode);
3571
3572 btrfs_end_transaction(trans);
3573 btrfs_btree_balance_dirty(fs_info);
3574out:
3575 iput(inode);
3576 return ret;
3577}
3578
3579
3580
3581
3582
3583static int find_data_references(struct reloc_control *rc,
3584 struct btrfs_key *extent_key,
3585 struct extent_buffer *leaf,
3586 struct btrfs_extent_data_ref *ref,
3587 struct rb_root *blocks)
3588{
3589 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
3590 struct btrfs_path *path;
3591 struct tree_block *block;
3592 struct btrfs_root *root;
3593 struct btrfs_file_extent_item *fi;
3594 struct rb_node *rb_node;
3595 struct btrfs_key key;
3596 u64 ref_root;
3597 u64 ref_objectid;
3598 u64 ref_offset;
3599 u32 ref_count;
3600 u32 nritems;
3601 int err = 0;
3602 int added = 0;
3603 int counted;
3604 int ret;
3605
3606 ref_root = btrfs_extent_data_ref_root(leaf, ref);
3607 ref_objectid = btrfs_extent_data_ref_objectid(leaf, ref);
3608 ref_offset = btrfs_extent_data_ref_offset(leaf, ref);
3609 ref_count = btrfs_extent_data_ref_count(leaf, ref);
3610
3611
3612
3613
3614
3615 if (ref_root == BTRFS_ROOT_TREE_OBJECTID) {
3616 ret = delete_block_group_cache(fs_info, rc->block_group,
3617 NULL, ref_objectid);
3618 if (ret != -ENOENT)
3619 return ret;
3620 ret = 0;
3621 }
3622
3623 path = btrfs_alloc_path();
3624 if (!path)
3625 return -ENOMEM;
3626 path->reada = READA_FORWARD;
3627
3628 root = read_fs_root(fs_info, ref_root);
3629 if (IS_ERR(root)) {
3630 err = PTR_ERR(root);
3631 goto out;
3632 }
3633
3634 key.objectid = ref_objectid;
3635 key.type = BTRFS_EXTENT_DATA_KEY;
3636 if (ref_offset > ((u64)-1 << 32))
3637 key.offset = 0;
3638 else
3639 key.offset = ref_offset;
3640
3641 path->search_commit_root = 1;
3642 path->skip_locking = 1;
3643 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
3644 if (ret < 0) {
3645 err = ret;
3646 goto out;
3647 }
3648
3649 leaf = path->nodes[0];
3650 nritems = btrfs_header_nritems(leaf);
3651
3652
3653
3654
3655 if (block_use_full_backref(rc, leaf))
3656 counted = 0;
3657 else
3658 counted = 1;
3659 rb_node = tree_search(blocks, leaf->start);
3660 if (rb_node) {
3661 if (counted)
3662 added = 1;
3663 else
3664 path->slots[0] = nritems;
3665 }
3666
3667 while (ref_count > 0) {
3668 while (path->slots[0] >= nritems) {
3669 ret = btrfs_next_leaf(root, path);
3670 if (ret < 0) {
3671 err = ret;
3672 goto out;
3673 }
3674 if (WARN_ON(ret > 0))
3675 goto out;
3676
3677 leaf = path->nodes[0];
3678 nritems = btrfs_header_nritems(leaf);
3679 added = 0;
3680
3681 if (block_use_full_backref(rc, leaf))
3682 counted = 0;
3683 else
3684 counted = 1;
3685 rb_node = tree_search(blocks, leaf->start);
3686 if (rb_node) {
3687 if (counted)
3688 added = 1;
3689 else
3690 path->slots[0] = nritems;
3691 }
3692 }
3693
3694 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3695 if (WARN_ON(key.objectid != ref_objectid ||
3696 key.type != BTRFS_EXTENT_DATA_KEY))
3697 break;
3698
3699 fi = btrfs_item_ptr(leaf, path->slots[0],
3700 struct btrfs_file_extent_item);
3701
3702 if (btrfs_file_extent_type(leaf, fi) ==
3703 BTRFS_FILE_EXTENT_INLINE)
3704 goto next;
3705
3706 if (btrfs_file_extent_disk_bytenr(leaf, fi) !=
3707 extent_key->objectid)
3708 goto next;
3709
3710 key.offset -= btrfs_file_extent_offset(leaf, fi);
3711 if (key.offset != ref_offset)
3712 goto next;
3713
3714 if (counted)
3715 ref_count--;
3716 if (added)
3717 goto next;
3718
3719 if (!tree_block_processed(leaf->start, rc)) {
3720 block = kmalloc(sizeof(*block), GFP_NOFS);
3721 if (!block) {
3722 err = -ENOMEM;
3723 break;
3724 }
3725 block->bytenr = leaf->start;
3726 btrfs_item_key_to_cpu(leaf, &block->key, 0);
3727 block->level = 0;
3728 block->key_ready = 1;
3729 rb_node = tree_insert(blocks, block->bytenr,
3730 &block->rb_node);
3731 if (rb_node)
3732 backref_tree_panic(rb_node, -EEXIST,
3733 block->bytenr);
3734 }
3735 if (counted)
3736 added = 1;
3737 else
3738 path->slots[0] = nritems;
3739next:
3740 path->slots[0]++;
3741
3742 }
3743out:
3744 btrfs_free_path(path);
3745 return err;
3746}
3747
3748
3749
3750
3751static noinline_for_stack
3752int add_data_references(struct reloc_control *rc,
3753 struct btrfs_key *extent_key,
3754 struct btrfs_path *path,
3755 struct rb_root *blocks)
3756{
3757 struct btrfs_key key;
3758 struct extent_buffer *eb;
3759 struct btrfs_extent_data_ref *dref;
3760 struct btrfs_extent_inline_ref *iref;
3761 unsigned long ptr;
3762 unsigned long end;
3763 u32 blocksize = rc->extent_root->fs_info->nodesize;
3764 int ret = 0;
3765 int err = 0;
3766
3767 eb = path->nodes[0];
3768 ptr = btrfs_item_ptr_offset(eb, path->slots[0]);
3769 end = ptr + btrfs_item_size_nr(eb, path->slots[0]);
3770 ptr += sizeof(struct btrfs_extent_item);
3771
3772 while (ptr < end) {
3773 iref = (struct btrfs_extent_inline_ref *)ptr;
3774 key.type = btrfs_get_extent_inline_ref_type(eb, iref,
3775 BTRFS_REF_TYPE_DATA);
3776 if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
3777 key.offset = btrfs_extent_inline_ref_offset(eb, iref);
3778 ret = __add_tree_block(rc, key.offset, blocksize,
3779 blocks);
3780 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
3781 dref = (struct btrfs_extent_data_ref *)(&iref->offset);
3782 ret = find_data_references(rc, extent_key,
3783 eb, dref, blocks);
3784 } else {
3785 ret = -EUCLEAN;
3786 btrfs_err(rc->extent_root->fs_info,
3787 "extent %llu slot %d has an invalid inline ref type",
3788 eb->start, path->slots[0]);
3789 }
3790 if (ret) {
3791 err = ret;
3792 goto out;
3793 }
3794 ptr += btrfs_extent_inline_ref_size(key.type);
3795 }
3796 WARN_ON(ptr > end);
3797
3798 while (1) {
3799 cond_resched();
3800 eb = path->nodes[0];
3801 if (path->slots[0] >= btrfs_header_nritems(eb)) {
3802 ret = btrfs_next_leaf(rc->extent_root, path);
3803 if (ret < 0) {
3804 err = ret;
3805 break;
3806 }
3807 if (ret > 0)
3808 break;
3809 eb = path->nodes[0];
3810 }
3811
3812 btrfs_item_key_to_cpu(eb, &key, path->slots[0]);
3813 if (key.objectid != extent_key->objectid)
3814 break;
3815
3816 if (key.type == BTRFS_SHARED_DATA_REF_KEY) {
3817 ret = __add_tree_block(rc, key.offset, blocksize,
3818 blocks);
3819 } else if (key.type == BTRFS_EXTENT_DATA_REF_KEY) {
3820 dref = btrfs_item_ptr(eb, path->slots[0],
3821 struct btrfs_extent_data_ref);
3822 ret = find_data_references(rc, extent_key,
3823 eb, dref, blocks);
3824 } else if (unlikely(key.type == BTRFS_EXTENT_REF_V0_KEY)) {
3825 btrfs_print_v0_err(eb->fs_info);
3826 btrfs_handle_fs_error(eb->fs_info, -EINVAL, NULL);
3827 ret = -EINVAL;
3828 } else {
3829 ret = 0;
3830 }
3831 if (ret) {
3832 err = ret;
3833 break;
3834 }
3835 path->slots[0]++;
3836 }
3837out:
3838 btrfs_release_path(path);
3839 if (err)
3840 free_block_list(blocks);
3841 return err;
3842}
3843
3844
3845
3846
3847static noinline_for_stack
3848int find_next_extent(struct reloc_control *rc, struct btrfs_path *path,
3849 struct btrfs_key *extent_key)
3850{
3851 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
3852 struct btrfs_key key;
3853 struct extent_buffer *leaf;
3854 u64 start, end, last;
3855 int ret;
3856
3857 last = rc->block_group->key.objectid + rc->block_group->key.offset;
3858 while (1) {
3859 cond_resched();
3860 if (rc->search_start >= last) {
3861 ret = 1;
3862 break;
3863 }
3864
3865 key.objectid = rc->search_start;
3866 key.type = BTRFS_EXTENT_ITEM_KEY;
3867 key.offset = 0;
3868
3869 path->search_commit_root = 1;
3870 path->skip_locking = 1;
3871 ret = btrfs_search_slot(NULL, rc->extent_root, &key, path,
3872 0, 0);
3873 if (ret < 0)
3874 break;
3875next:
3876 leaf = path->nodes[0];
3877 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
3878 ret = btrfs_next_leaf(rc->extent_root, path);
3879 if (ret != 0)
3880 break;
3881 leaf = path->nodes[0];
3882 }
3883
3884 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
3885 if (key.objectid >= last) {
3886 ret = 1;
3887 break;
3888 }
3889
3890 if (key.type != BTRFS_EXTENT_ITEM_KEY &&
3891 key.type != BTRFS_METADATA_ITEM_KEY) {
3892 path->slots[0]++;
3893 goto next;
3894 }
3895
3896 if (key.type == BTRFS_EXTENT_ITEM_KEY &&
3897 key.objectid + key.offset <= rc->search_start) {
3898 path->slots[0]++;
3899 goto next;
3900 }
3901
3902 if (key.type == BTRFS_METADATA_ITEM_KEY &&
3903 key.objectid + fs_info->nodesize <=
3904 rc->search_start) {
3905 path->slots[0]++;
3906 goto next;
3907 }
3908
3909 ret = find_first_extent_bit(&rc->processed_blocks,
3910 key.objectid, &start, &end,
3911 EXTENT_DIRTY, NULL);
3912
3913 if (ret == 0 && start <= key.objectid) {
3914 btrfs_release_path(path);
3915 rc->search_start = end + 1;
3916 } else {
3917 if (key.type == BTRFS_EXTENT_ITEM_KEY)
3918 rc->search_start = key.objectid + key.offset;
3919 else
3920 rc->search_start = key.objectid +
3921 fs_info->nodesize;
3922 memcpy(extent_key, &key, sizeof(key));
3923 return 0;
3924 }
3925 }
3926 btrfs_release_path(path);
3927 return ret;
3928}
3929
3930static void set_reloc_control(struct reloc_control *rc)
3931{
3932 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
3933
3934 mutex_lock(&fs_info->reloc_mutex);
3935 fs_info->reloc_ctl = rc;
3936 mutex_unlock(&fs_info->reloc_mutex);
3937}
3938
3939static void unset_reloc_control(struct reloc_control *rc)
3940{
3941 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
3942
3943 mutex_lock(&fs_info->reloc_mutex);
3944 fs_info->reloc_ctl = NULL;
3945 mutex_unlock(&fs_info->reloc_mutex);
3946}
3947
3948static int check_extent_flags(u64 flags)
3949{
3950 if ((flags & BTRFS_EXTENT_FLAG_DATA) &&
3951 (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK))
3952 return 1;
3953 if (!(flags & BTRFS_EXTENT_FLAG_DATA) &&
3954 !(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK))
3955 return 1;
3956 if ((flags & BTRFS_EXTENT_FLAG_DATA) &&
3957 (flags & BTRFS_BLOCK_FLAG_FULL_BACKREF))
3958 return 1;
3959 return 0;
3960}
3961
3962static noinline_for_stack
3963int prepare_to_relocate(struct reloc_control *rc)
3964{
3965 struct btrfs_trans_handle *trans;
3966 int ret;
3967
3968 rc->block_rsv = btrfs_alloc_block_rsv(rc->extent_root->fs_info,
3969 BTRFS_BLOCK_RSV_TEMP);
3970 if (!rc->block_rsv)
3971 return -ENOMEM;
3972
3973 memset(&rc->cluster, 0, sizeof(rc->cluster));
3974 rc->search_start = rc->block_group->key.objectid;
3975 rc->extents_found = 0;
3976 rc->nodes_relocated = 0;
3977 rc->merging_rsv_size = 0;
3978 rc->reserved_bytes = 0;
3979 rc->block_rsv->size = rc->extent_root->fs_info->nodesize *
3980 RELOCATION_RESERVED_NODES;
3981 ret = btrfs_block_rsv_refill(rc->extent_root,
3982 rc->block_rsv, rc->block_rsv->size,
3983 BTRFS_RESERVE_FLUSH_ALL);
3984 if (ret)
3985 return ret;
3986
3987 rc->create_reloc_tree = 1;
3988 set_reloc_control(rc);
3989
3990 trans = btrfs_join_transaction(rc->extent_root);
3991 if (IS_ERR(trans)) {
3992 unset_reloc_control(rc);
3993
3994
3995
3996
3997
3998 return PTR_ERR(trans);
3999 }
4000 btrfs_commit_transaction(trans);
4001 return 0;
4002}
4003
4004static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
4005{
4006 struct btrfs_fs_info *fs_info = rc->extent_root->fs_info;
4007 struct rb_root blocks = RB_ROOT;
4008 struct btrfs_key key;
4009 struct btrfs_trans_handle *trans = NULL;
4010 struct btrfs_path *path;
4011 struct btrfs_extent_item *ei;
4012 u64 flags;
4013 u32 item_size;
4014 int ret;
4015 int err = 0;
4016 int progress = 0;
4017
4018 path = btrfs_alloc_path();
4019 if (!path)
4020 return -ENOMEM;
4021 path->reada = READA_FORWARD;
4022
4023 ret = prepare_to_relocate(rc);
4024 if (ret) {
4025 err = ret;
4026 goto out_free;
4027 }
4028
4029 while (1) {
4030 rc->reserved_bytes = 0;
4031 ret = btrfs_block_rsv_refill(rc->extent_root,
4032 rc->block_rsv, rc->block_rsv->size,
4033 BTRFS_RESERVE_FLUSH_ALL);
4034 if (ret) {
4035 err = ret;
4036 break;
4037 }
4038 progress++;
4039 trans = btrfs_start_transaction(rc->extent_root, 0);
4040 if (IS_ERR(trans)) {
4041 err = PTR_ERR(trans);
4042 trans = NULL;
4043 break;
4044 }
4045restart:
4046 if (update_backref_cache(trans, &rc->backref_cache)) {
4047 btrfs_end_transaction(trans);
4048 trans = NULL;
4049 continue;
4050 }
4051
4052 ret = find_next_extent(rc, path, &key);
4053 if (ret < 0)
4054 err = ret;
4055 if (ret != 0)
4056 break;
4057
4058 rc->extents_found++;
4059
4060 ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
4061 struct btrfs_extent_item);
4062 item_size = btrfs_item_size_nr(path->nodes[0], path->slots[0]);
4063 if (item_size >= sizeof(*ei)) {
4064 flags = btrfs_extent_flags(path->nodes[0], ei);
4065 ret = check_extent_flags(flags);
4066 BUG_ON(ret);
4067 } else if (unlikely(item_size == sizeof(struct btrfs_extent_item_v0))) {
4068 err = -EINVAL;
4069 btrfs_print_v0_err(trans->fs_info);
4070 btrfs_abort_transaction(trans, err);
4071 break;
4072 } else {
4073 BUG();
4074 }
4075
4076 if (flags & BTRFS_EXTENT_FLAG_TREE_BLOCK) {
4077 ret = add_tree_block(rc, &key, path, &blocks);
4078 } else if (rc->stage == UPDATE_DATA_PTRS &&
4079 (flags & BTRFS_EXTENT_FLAG_DATA)) {
4080 ret = add_data_references(rc, &key, path, &blocks);
4081 } else {
4082 btrfs_release_path(path);
4083 ret = 0;
4084 }
4085 if (ret < 0) {
4086 err = ret;
4087 break;
4088 }
4089
4090 if (!RB_EMPTY_ROOT(&blocks)) {
4091 ret = relocate_tree_blocks(trans, rc, &blocks);
4092 if (ret < 0) {
4093
4094
4095
4096
4097 rc->backref_cache.last_trans = trans->transid - 1;
4098
4099 if (ret != -EAGAIN) {
4100 err = ret;
4101 break;
4102 }
4103 rc->extents_found--;
4104 rc->search_start = key.objectid;
4105 }
4106 }
4107
4108 btrfs_end_transaction_throttle(trans);
4109 btrfs_btree_balance_dirty(fs_info);
4110 trans = NULL;
4111
4112 if (rc->stage == MOVE_DATA_EXTENTS &&
4113 (flags & BTRFS_EXTENT_FLAG_DATA)) {
4114 rc->found_file_extent = 1;
4115 ret = relocate_data_extent(rc->data_inode,
4116 &key, &rc->cluster);
4117 if (ret < 0) {
4118 err = ret;
4119 break;
4120 }
4121 }
4122 }
4123 if (trans && progress && err == -ENOSPC) {
4124 ret = btrfs_force_chunk_alloc(trans, rc->block_group->flags);
4125 if (ret == 1) {
4126 err = 0;
4127 progress = 0;
4128 goto restart;
4129 }
4130 }
4131
4132 btrfs_release_path(path);
4133 clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY);
4134
4135 if (trans) {
4136 btrfs_end_transaction_throttle(trans);
4137 btrfs_btree_balance_dirty(fs_info);
4138 }
4139
4140 if (!err) {
4141 ret = relocate_file_extent_cluster(rc->data_inode,
4142 &rc->cluster);
4143 if (ret < 0)
4144 err = ret;
4145 }
4146
4147 rc->create_reloc_tree = 0;
4148 set_reloc_control(rc);
4149
4150 backref_cache_cleanup(&rc->backref_cache);
4151 btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1);
4152
4153 err = prepare_to_merge(rc, err);
4154
4155 merge_reloc_roots(rc);
4156
4157 rc->merge_reloc_tree = 0;
4158 unset_reloc_control(rc);
4159 btrfs_block_rsv_release(fs_info, rc->block_rsv, (u64)-1);
4160
4161
4162 trans = btrfs_join_transaction(rc->extent_root);
4163 if (IS_ERR(trans)) {
4164 err = PTR_ERR(trans);
4165 goto out_free;
4166 }
4167 btrfs_commit_transaction(trans);
4168 ret = clean_dirty_subvols(rc);
4169 if (ret < 0 && !err)
4170 err = ret;
4171out_free:
4172 btrfs_free_block_rsv(fs_info, rc->block_rsv);
4173 btrfs_free_path(path);
4174 return err;
4175}
4176
4177static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
4178 struct btrfs_root *root, u64 objectid)
4179{
4180 struct btrfs_path *path;
4181 struct btrfs_inode_item *item;
4182 struct extent_buffer *leaf;
4183 int ret;
4184
4185 path = btrfs_alloc_path();
4186 if (!path)
4187 return -ENOMEM;
4188
4189 ret = btrfs_insert_empty_inode(trans, root, path, objectid);
4190 if (ret)
4191 goto out;
4192
4193 leaf = path->nodes[0];
4194 item = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_inode_item);
4195 memzero_extent_buffer(leaf, (unsigned long)item, sizeof(*item));
4196 btrfs_set_inode_generation(leaf, item, 1);
4197 btrfs_set_inode_size(leaf, item, 0);
4198 btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
4199 btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS |
4200 BTRFS_INODE_PREALLOC);
4201 btrfs_mark_buffer_dirty(leaf);
4202out:
4203 btrfs_free_path(path);
4204 return ret;
4205}
4206
4207
4208
4209
4210
4211static noinline_for_stack
4212struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
4213 struct btrfs_block_group_cache *group)
4214{
4215 struct inode *inode = NULL;
4216 struct btrfs_trans_handle *trans;
4217 struct btrfs_root *root;
4218 struct btrfs_key key;
4219 u64 objectid;
4220 int err = 0;
4221
4222 root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID);
4223 if (IS_ERR(root))
4224 return ERR_CAST(root);
4225
4226 trans = btrfs_start_transaction(root, 6);
4227 if (IS_ERR(trans))
4228 return ERR_CAST(trans);
4229
4230 err = btrfs_find_free_objectid(root, &objectid);
4231 if (err)
4232 goto out;
4233
4234 err = __insert_orphan_inode(trans, root, objectid);
4235 BUG_ON(err);
4236
4237 key.objectid = objectid;
4238 key.type = BTRFS_INODE_ITEM_KEY;
4239 key.offset = 0;
4240 inode = btrfs_iget(fs_info->sb, &key, root, NULL);
4241 BUG_ON(IS_ERR(inode));
4242 BTRFS_I(inode)->index_cnt = group->key.objectid;
4243
4244 err = btrfs_orphan_add(trans, BTRFS_I(inode));
4245out:
4246 btrfs_end_transaction(trans);
4247 btrfs_btree_balance_dirty(fs_info);
4248 if (err) {
4249 if (inode)
4250 iput(inode);
4251 inode = ERR_PTR(err);
4252 }
4253 return inode;
4254}
4255
4256static struct reloc_control *alloc_reloc_control(struct btrfs_fs_info *fs_info)
4257{
4258 struct reloc_control *rc;
4259
4260 rc = kzalloc(sizeof(*rc), GFP_NOFS);
4261 if (!rc)
4262 return NULL;
4263
4264 INIT_LIST_HEAD(&rc->reloc_roots);
4265 INIT_LIST_HEAD(&rc->dirty_subvol_roots);
4266 backref_cache_init(&rc->backref_cache);
4267 mapping_tree_init(&rc->reloc_root_tree);
4268 extent_io_tree_init(fs_info, &rc->processed_blocks,
4269 IO_TREE_RELOC_BLOCKS, NULL);
4270 return rc;
4271}
4272
4273
4274
4275
4276static void describe_relocation(struct btrfs_fs_info *fs_info,
4277 struct btrfs_block_group_cache *block_group)
4278{
4279 char buf[128] = {'\0'};
4280
4281 btrfs_describe_block_groups(block_group->flags, buf, sizeof(buf));
4282
4283 btrfs_info(fs_info,
4284 "relocating block group %llu flags %s",
4285 block_group->key.objectid, buf);
4286}
4287
4288
4289
4290
4291int btrfs_relocate_block_group(struct btrfs_fs_info *fs_info, u64 group_start)
4292{
4293 struct btrfs_block_group_cache *bg;
4294 struct btrfs_root *extent_root = fs_info->extent_root;
4295 struct reloc_control *rc;
4296 struct inode *inode;
4297 struct btrfs_path *path;
4298 int ret;
4299 int rw = 0;
4300 int err = 0;
4301
4302 bg = btrfs_lookup_block_group(fs_info, group_start);
4303 if (!bg)
4304 return -ENOENT;
4305
4306 if (btrfs_pinned_by_swapfile(fs_info, bg)) {
4307 btrfs_put_block_group(bg);
4308 return -ETXTBSY;
4309 }
4310
4311 rc = alloc_reloc_control(fs_info);
4312 if (!rc) {
4313 btrfs_put_block_group(bg);
4314 return -ENOMEM;
4315 }
4316
4317 rc->extent_root = extent_root;
4318 rc->block_group = bg;
4319
4320 ret = btrfs_inc_block_group_ro(rc->block_group);
4321 if (ret) {
4322 err = ret;
4323 goto out;
4324 }
4325 rw = 1;
4326
4327 path = btrfs_alloc_path();
4328 if (!path) {
4329 err = -ENOMEM;
4330 goto out;
4331 }
4332
4333 inode = lookup_free_space_inode(rc->block_group, path);
4334 btrfs_free_path(path);
4335
4336 if (!IS_ERR(inode))
4337 ret = delete_block_group_cache(fs_info, rc->block_group, inode, 0);
4338 else
4339 ret = PTR_ERR(inode);
4340
4341 if (ret && ret != -ENOENT) {
4342 err = ret;
4343 goto out;
4344 }
4345
4346 rc->data_inode = create_reloc_inode(fs_info, rc->block_group);
4347 if (IS_ERR(rc->data_inode)) {
4348 err = PTR_ERR(rc->data_inode);
4349 rc->data_inode = NULL;
4350 goto out;
4351 }
4352
4353 describe_relocation(fs_info, rc->block_group);
4354
4355 btrfs_wait_block_group_reservations(rc->block_group);
4356 btrfs_wait_nocow_writers(rc->block_group);
4357 btrfs_wait_ordered_roots(fs_info, U64_MAX,
4358 rc->block_group->key.objectid,
4359 rc->block_group->key.offset);
4360
4361 while (1) {
4362 mutex_lock(&fs_info->cleaner_mutex);
4363 ret = relocate_block_group(rc);
4364 mutex_unlock(&fs_info->cleaner_mutex);
4365 if (ret < 0)
4366 err = ret;
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377 if (rc->stage == MOVE_DATA_EXTENTS && rc->found_file_extent) {
4378 ret = btrfs_wait_ordered_range(rc->data_inode, 0,
4379 (u64)-1);
4380 if (ret)
4381 err = ret;
4382 invalidate_mapping_pages(rc->data_inode->i_mapping,
4383 0, -1);
4384 rc->stage = UPDATE_DATA_PTRS;
4385 }
4386
4387 if (err < 0)
4388 goto out;
4389
4390 if (rc->extents_found == 0)
4391 break;
4392
4393 btrfs_info(fs_info, "found %llu extents", rc->extents_found);
4394
4395 }
4396
4397 WARN_ON(rc->block_group->pinned > 0);
4398 WARN_ON(rc->block_group->reserved > 0);
4399 WARN_ON(btrfs_block_group_used(&rc->block_group->item) > 0);
4400out:
4401 if (err && rw)
4402 btrfs_dec_block_group_ro(rc->block_group);
4403 iput(rc->data_inode);
4404 btrfs_put_block_group(rc->block_group);
4405 kfree(rc);
4406 return err;
4407}
4408
4409static noinline_for_stack int mark_garbage_root(struct btrfs_root *root)
4410{
4411 struct btrfs_fs_info *fs_info = root->fs_info;
4412 struct btrfs_trans_handle *trans;
4413 int ret, err;
4414
4415 trans = btrfs_start_transaction(fs_info->tree_root, 0);
4416 if (IS_ERR(trans))
4417 return PTR_ERR(trans);
4418
4419 memset(&root->root_item.drop_progress, 0,
4420 sizeof(root->root_item.drop_progress));
4421 root->root_item.drop_level = 0;
4422 btrfs_set_root_refs(&root->root_item, 0);
4423 ret = btrfs_update_root(trans, fs_info->tree_root,
4424 &root->root_key, &root->root_item);
4425
4426 err = btrfs_end_transaction(trans);
4427 if (err)
4428 return err;
4429 return ret;
4430}
4431
4432
4433
4434
4435
4436
4437
4438int btrfs_recover_relocation(struct btrfs_root *root)
4439{
4440 struct btrfs_fs_info *fs_info = root->fs_info;
4441 LIST_HEAD(reloc_roots);
4442 struct btrfs_key key;
4443 struct btrfs_root *fs_root;
4444 struct btrfs_root *reloc_root;
4445 struct btrfs_path *path;
4446 struct extent_buffer *leaf;
4447 struct reloc_control *rc = NULL;
4448 struct btrfs_trans_handle *trans;
4449 int ret;
4450 int err = 0;
4451
4452 path = btrfs_alloc_path();
4453 if (!path)
4454 return -ENOMEM;
4455 path->reada = READA_BACK;
4456
4457 key.objectid = BTRFS_TREE_RELOC_OBJECTID;
4458 key.type = BTRFS_ROOT_ITEM_KEY;
4459 key.offset = (u64)-1;
4460
4461 while (1) {
4462 ret = btrfs_search_slot(NULL, fs_info->tree_root, &key,
4463 path, 0, 0);
4464 if (ret < 0) {
4465 err = ret;
4466 goto out;
4467 }
4468 if (ret > 0) {
4469 if (path->slots[0] == 0)
4470 break;
4471 path->slots[0]--;
4472 }
4473 leaf = path->nodes[0];
4474 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
4475 btrfs_release_path(path);
4476
4477 if (key.objectid != BTRFS_TREE_RELOC_OBJECTID ||
4478 key.type != BTRFS_ROOT_ITEM_KEY)
4479 break;
4480
4481 reloc_root = btrfs_read_fs_root(root, &key);
4482 if (IS_ERR(reloc_root)) {
4483 err = PTR_ERR(reloc_root);
4484 goto out;
4485 }
4486
4487 list_add(&reloc_root->root_list, &reloc_roots);
4488
4489 if (btrfs_root_refs(&reloc_root->root_item) > 0) {
4490 fs_root = read_fs_root(fs_info,
4491 reloc_root->root_key.offset);
4492 if (IS_ERR(fs_root)) {
4493 ret = PTR_ERR(fs_root);
4494 if (ret != -ENOENT) {
4495 err = ret;
4496 goto out;
4497 }
4498 ret = mark_garbage_root(reloc_root);
4499 if (ret < 0) {
4500 err = ret;
4501 goto out;
4502 }
4503 }
4504 }
4505
4506 if (key.offset == 0)
4507 break;
4508
4509 key.offset--;
4510 }
4511 btrfs_release_path(path);
4512
4513 if (list_empty(&reloc_roots))
4514 goto out;
4515
4516 rc = alloc_reloc_control(fs_info);
4517 if (!rc) {
4518 err = -ENOMEM;
4519 goto out;
4520 }
4521
4522 rc->extent_root = fs_info->extent_root;
4523
4524 set_reloc_control(rc);
4525
4526 trans = btrfs_join_transaction(rc->extent_root);
4527 if (IS_ERR(trans)) {
4528 unset_reloc_control(rc);
4529 err = PTR_ERR(trans);
4530 goto out_free;
4531 }
4532
4533 rc->merge_reloc_tree = 1;
4534
4535 while (!list_empty(&reloc_roots)) {
4536 reloc_root = list_entry(reloc_roots.next,
4537 struct btrfs_root, root_list);
4538 list_del(&reloc_root->root_list);
4539
4540 if (btrfs_root_refs(&reloc_root->root_item) == 0) {
4541 list_add_tail(&reloc_root->root_list,
4542 &rc->reloc_roots);
4543 continue;
4544 }
4545
4546 fs_root = read_fs_root(fs_info, reloc_root->root_key.offset);
4547 if (IS_ERR(fs_root)) {
4548 err = PTR_ERR(fs_root);
4549 goto out_free;
4550 }
4551
4552 err = __add_reloc_root(reloc_root);
4553 BUG_ON(err < 0);
4554 fs_root->reloc_root = reloc_root;
4555 }
4556
4557 err = btrfs_commit_transaction(trans);
4558 if (err)
4559 goto out_free;
4560
4561 merge_reloc_roots(rc);
4562
4563 unset_reloc_control(rc);
4564
4565 trans = btrfs_join_transaction(rc->extent_root);
4566 if (IS_ERR(trans)) {
4567 err = PTR_ERR(trans);
4568 goto out_free;
4569 }
4570 err = btrfs_commit_transaction(trans);
4571
4572 ret = clean_dirty_subvols(rc);
4573 if (ret < 0 && !err)
4574 err = ret;
4575out_free:
4576 kfree(rc);
4577out:
4578 if (!list_empty(&reloc_roots))
4579 free_reloc_roots(&reloc_roots);
4580
4581 btrfs_free_path(path);
4582
4583 if (err == 0) {
4584
4585 fs_root = read_fs_root(fs_info, BTRFS_DATA_RELOC_TREE_OBJECTID);
4586 if (IS_ERR(fs_root))
4587 err = PTR_ERR(fs_root);
4588 else
4589 err = btrfs_orphan_cleanup(fs_root);
4590 }
4591 return err;
4592}
4593
4594
4595
4596
4597
4598
4599
4600int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
4601{
4602 struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
4603 struct btrfs_ordered_sum *sums;
4604 struct btrfs_ordered_extent *ordered;
4605 int ret;
4606 u64 disk_bytenr;
4607 u64 new_bytenr;
4608 LIST_HEAD(list);
4609
4610 ordered = btrfs_lookup_ordered_extent(inode, file_pos);
4611 BUG_ON(ordered->file_offset != file_pos || ordered->len != len);
4612
4613 disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt;
4614 ret = btrfs_lookup_csums_range(fs_info->csum_root, disk_bytenr,
4615 disk_bytenr + len - 1, &list, 0);
4616 if (ret)
4617 goto out;
4618
4619 while (!list_empty(&list)) {
4620 sums = list_entry(list.next, struct btrfs_ordered_sum, list);
4621 list_del_init(&sums->list);
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635 new_bytenr = ordered->start + (sums->bytenr - disk_bytenr);
4636 sums->bytenr = new_bytenr;
4637
4638 btrfs_add_ordered_sum(ordered, sums);
4639 }
4640out:
4641 btrfs_put_ordered_extent(ordered);
4642 return ret;
4643}
4644
4645int btrfs_reloc_cow_block(struct btrfs_trans_handle *trans,
4646 struct btrfs_root *root, struct extent_buffer *buf,
4647 struct extent_buffer *cow)
4648{
4649 struct btrfs_fs_info *fs_info = root->fs_info;
4650 struct reloc_control *rc;
4651 struct backref_node *node;
4652 int first_cow = 0;
4653 int level;
4654 int ret = 0;
4655
4656 rc = fs_info->reloc_ctl;
4657 if (!rc)
4658 return 0;
4659
4660 BUG_ON(rc->stage == UPDATE_DATA_PTRS &&
4661 root->root_key.objectid == BTRFS_DATA_RELOC_TREE_OBJECTID);
4662
4663 if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID) {
4664 if (buf == root->node)
4665 __update_reloc_root(root, cow->start);
4666 }
4667
4668 level = btrfs_header_level(buf);
4669 if (btrfs_header_generation(buf) <=
4670 btrfs_root_last_snapshot(&root->root_item))
4671 first_cow = 1;
4672
4673 if (root->root_key.objectid == BTRFS_TREE_RELOC_OBJECTID &&
4674 rc->create_reloc_tree) {
4675 WARN_ON(!first_cow && level == 0);
4676
4677 node = rc->backref_cache.path[level];
4678 BUG_ON(node->bytenr != buf->start &&
4679 node->new_bytenr != buf->start);
4680
4681 drop_node_buffer(node);
4682 extent_buffer_get(cow);
4683 node->eb = cow;
4684 node->new_bytenr = cow->start;
4685
4686 if (!node->pending) {
4687 list_move_tail(&node->list,
4688 &rc->backref_cache.pending[level]);
4689 node->pending = 1;
4690 }
4691
4692 if (first_cow)
4693 __mark_block_processed(rc, node);
4694
4695 if (first_cow && level > 0)
4696 rc->nodes_relocated += buf->len;
4697 }
4698
4699 if (level == 0 && first_cow && rc->stage == UPDATE_DATA_PTRS)
4700 ret = replace_file_extents(trans, rc, root, cow);
4701 return ret;
4702}
4703
4704
4705
4706
4707
4708void btrfs_reloc_pre_snapshot(struct btrfs_pending_snapshot *pending,
4709 u64 *bytes_to_reserve)
4710{
4711 struct btrfs_root *root = pending->root;
4712 struct reloc_control *rc = root->fs_info->reloc_ctl;
4713
4714 if (!root->reloc_root || !rc)
4715 return;
4716
4717 if (!rc->merge_reloc_tree)
4718 return;
4719
4720 root = root->reloc_root;
4721 BUG_ON(btrfs_root_refs(&root->root_item) == 0);
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732 *bytes_to_reserve += rc->nodes_relocated;
4733}
4734
4735
4736
4737
4738
4739int btrfs_reloc_post_snapshot(struct btrfs_trans_handle *trans,
4740 struct btrfs_pending_snapshot *pending)
4741{
4742 struct btrfs_root *root = pending->root;
4743 struct btrfs_root *reloc_root;
4744 struct btrfs_root *new_root;
4745 struct reloc_control *rc = root->fs_info->reloc_ctl;
4746 int ret;
4747
4748 if (!root->reloc_root || !rc)
4749 return 0;
4750
4751 rc = root->fs_info->reloc_ctl;
4752 rc->merging_rsv_size += rc->nodes_relocated;
4753
4754 if (rc->merge_reloc_tree) {
4755 ret = btrfs_block_rsv_migrate(&pending->block_rsv,
4756 rc->block_rsv,
4757 rc->nodes_relocated, true);
4758 if (ret)
4759 return ret;
4760 }
4761
4762 new_root = pending->snap;
4763 reloc_root = create_reloc_root(trans, root->reloc_root,
4764 new_root->root_key.objectid);
4765 if (IS_ERR(reloc_root))
4766 return PTR_ERR(reloc_root);
4767
4768 ret = __add_reloc_root(reloc_root);
4769 BUG_ON(ret < 0);
4770 new_root->reloc_root = reloc_root;
4771
4772 if (rc->create_reloc_tree)
4773 ret = clone_backref_node(trans, rc, root, reloc_root);
4774 return ret;
4775}
4776