1 // SPDX-License-Identifier: GPL-2.0
3 * Copyright (C) 2009 Oracle. All rights reserved.
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>
14 #include "transaction.h"
17 #include "btrfs_inode.h"
18 #include "async-thread.h"
19 #include "free-space-cache.h"
20 #include "inode-map.h"
22 #include "print-tree.h"
25 * backref_node, mapping_node and tree_block start with this
28 struct rb_node rb_node
;
33 * present a tree block in the backref cache
36 struct rb_node rb_node
;
40 /* objectid of tree block owner, can be not uptodate */
42 /* link to pending, changed or detached list */
43 struct list_head list
;
44 /* list of upper level blocks reference this block */
45 struct list_head upper
;
46 /* list of child blocks in the cache */
47 struct list_head lower
;
48 /* NULL if this node is not tree root */
49 struct btrfs_root
*root
;
50 /* extent buffer got by COW the block */
51 struct extent_buffer
*eb
;
52 /* level of tree block */
54 /* is the block in non-reference counted tree */
55 unsigned int cowonly
:1;
56 /* 1 if no child node in the cache */
57 unsigned int lowest
:1;
58 /* is the extent buffer locked */
59 unsigned int locked
:1;
60 /* has the block been processed */
61 unsigned int processed
:1;
62 /* have backrefs of this block been checked */
63 unsigned int checked
:1;
65 * 1 if corresponding block has been cowed but some upper
66 * level block pointers may not point to the new location
68 unsigned int pending
:1;
70 * 1 if the backref node isn't connected to any other
73 unsigned int detached
:1;
77 * present a block pointer in the backref cache
80 struct list_head list
[2];
81 struct backref_node
*node
[2];
86 #define RELOCATION_RESERVED_NODES 256
88 struct backref_cache
{
89 /* red black tree of all backref nodes in the cache */
90 struct rb_root rb_root
;
91 /* for passing backref nodes to btrfs_reloc_cow_block */
92 struct backref_node
*path
[BTRFS_MAX_LEVEL
];
94 * list of blocks that have been cowed but some block
95 * pointers in upper level blocks may not reflect the
98 struct list_head pending
[BTRFS_MAX_LEVEL
];
99 /* list of backref nodes with no child node */
100 struct list_head leaves
;
101 /* list of blocks that have been cowed in current transaction */
102 struct list_head changed
;
103 /* list of detached backref node. */
104 struct list_head detached
;
113 * map address of tree root to tree
115 struct mapping_node
{
116 struct rb_node rb_node
;
121 struct mapping_tree
{
122 struct rb_root rb_root
;
127 * present a tree block to process
130 struct rb_node rb_node
;
132 struct btrfs_key key
;
133 unsigned int level
:8;
134 unsigned int key_ready
:1;
137 #define MAX_EXTENTS 128
139 struct file_extent_cluster
{
142 u64 boundary
[MAX_EXTENTS
];
146 struct reloc_control
{
147 /* block group to relocate */
148 struct btrfs_block_group_cache
*block_group
;
150 struct btrfs_root
*extent_root
;
151 /* inode for moving data */
152 struct inode
*data_inode
;
154 struct btrfs_block_rsv
*block_rsv
;
156 struct backref_cache backref_cache
;
158 struct file_extent_cluster cluster
;
159 /* tree blocks have been processed */
160 struct extent_io_tree processed_blocks
;
161 /* map start of tree root to corresponding reloc tree */
162 struct mapping_tree reloc_root_tree
;
163 /* list of reloc trees */
164 struct list_head reloc_roots
;
165 /* list of subvolume trees that get relocated */
166 struct list_head dirty_subvol_roots
;
167 /* size of metadata reservation for merging reloc trees */
168 u64 merging_rsv_size
;
169 /* size of relocated tree nodes */
171 /* reserved size for block group relocation*/
177 unsigned int stage
:8;
178 unsigned int create_reloc_tree
:1;
179 unsigned int merge_reloc_tree
:1;
180 unsigned int found_file_extent
:1;
183 /* stages of data relocation */
184 #define MOVE_DATA_EXTENTS 0
185 #define UPDATE_DATA_PTRS 1
187 static void remove_backref_node(struct backref_cache
*cache
,
188 struct backref_node
*node
);
189 static void __mark_block_processed(struct reloc_control
*rc
,
190 struct backref_node
*node
);
192 static void mapping_tree_init(struct mapping_tree
*tree
)
194 tree
->rb_root
= RB_ROOT
;
195 spin_lock_init(&tree
->lock
);
198 static void backref_cache_init(struct backref_cache
*cache
)
201 cache
->rb_root
= RB_ROOT
;
202 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++)
203 INIT_LIST_HEAD(&cache
->pending
[i
]);
204 INIT_LIST_HEAD(&cache
->changed
);
205 INIT_LIST_HEAD(&cache
->detached
);
206 INIT_LIST_HEAD(&cache
->leaves
);
209 static void backref_cache_cleanup(struct backref_cache
*cache
)
211 struct backref_node
*node
;
214 while (!list_empty(&cache
->detached
)) {
215 node
= list_entry(cache
->detached
.next
,
216 struct backref_node
, list
);
217 remove_backref_node(cache
, node
);
220 while (!list_empty(&cache
->leaves
)) {
221 node
= list_entry(cache
->leaves
.next
,
222 struct backref_node
, lower
);
223 remove_backref_node(cache
, node
);
226 cache
->last_trans
= 0;
228 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++)
229 ASSERT(list_empty(&cache
->pending
[i
]));
230 ASSERT(list_empty(&cache
->changed
));
231 ASSERT(list_empty(&cache
->detached
));
232 ASSERT(RB_EMPTY_ROOT(&cache
->rb_root
));
233 ASSERT(!cache
->nr_nodes
);
234 ASSERT(!cache
->nr_edges
);
237 static struct backref_node
*alloc_backref_node(struct backref_cache
*cache
)
239 struct backref_node
*node
;
241 node
= kzalloc(sizeof(*node
), GFP_NOFS
);
243 INIT_LIST_HEAD(&node
->list
);
244 INIT_LIST_HEAD(&node
->upper
);
245 INIT_LIST_HEAD(&node
->lower
);
246 RB_CLEAR_NODE(&node
->rb_node
);
252 static void free_backref_node(struct backref_cache
*cache
,
253 struct backref_node
*node
)
261 static struct backref_edge
*alloc_backref_edge(struct backref_cache
*cache
)
263 struct backref_edge
*edge
;
265 edge
= kzalloc(sizeof(*edge
), GFP_NOFS
);
271 static void free_backref_edge(struct backref_cache
*cache
,
272 struct backref_edge
*edge
)
280 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 bytenr
,
281 struct rb_node
*node
)
283 struct rb_node
**p
= &root
->rb_node
;
284 struct rb_node
*parent
= NULL
;
285 struct tree_entry
*entry
;
289 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
291 if (bytenr
< entry
->bytenr
)
293 else if (bytenr
> entry
->bytenr
)
299 rb_link_node(node
, parent
, p
);
300 rb_insert_color(node
, root
);
304 static struct rb_node
*tree_search(struct rb_root
*root
, u64 bytenr
)
306 struct rb_node
*n
= root
->rb_node
;
307 struct tree_entry
*entry
;
310 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
312 if (bytenr
< entry
->bytenr
)
314 else if (bytenr
> entry
->bytenr
)
322 static void backref_tree_panic(struct rb_node
*rb_node
, int errno
, u64 bytenr
)
325 struct btrfs_fs_info
*fs_info
= NULL
;
326 struct backref_node
*bnode
= rb_entry(rb_node
, struct backref_node
,
329 fs_info
= bnode
->root
->fs_info
;
330 btrfs_panic(fs_info
, errno
,
331 "Inconsistency in backref cache found at offset %llu",
336 * walk up backref nodes until reach node presents tree root
338 static struct backref_node
*walk_up_backref(struct backref_node
*node
,
339 struct backref_edge
*edges
[],
342 struct backref_edge
*edge
;
345 while (!list_empty(&node
->upper
)) {
346 edge
= list_entry(node
->upper
.next
,
347 struct backref_edge
, list
[LOWER
]);
349 node
= edge
->node
[UPPER
];
351 BUG_ON(node
->detached
);
357 * walk down backref nodes to find start of next reference path
359 static struct backref_node
*walk_down_backref(struct backref_edge
*edges
[],
362 struct backref_edge
*edge
;
363 struct backref_node
*lower
;
367 edge
= edges
[idx
- 1];
368 lower
= edge
->node
[LOWER
];
369 if (list_is_last(&edge
->list
[LOWER
], &lower
->upper
)) {
373 edge
= list_entry(edge
->list
[LOWER
].next
,
374 struct backref_edge
, list
[LOWER
]);
375 edges
[idx
- 1] = edge
;
377 return edge
->node
[UPPER
];
383 static void unlock_node_buffer(struct backref_node
*node
)
386 btrfs_tree_unlock(node
->eb
);
391 static void drop_node_buffer(struct backref_node
*node
)
394 unlock_node_buffer(node
);
395 free_extent_buffer(node
->eb
);
400 static void drop_backref_node(struct backref_cache
*tree
,
401 struct backref_node
*node
)
403 BUG_ON(!list_empty(&node
->upper
));
405 drop_node_buffer(node
);
406 list_del(&node
->list
);
407 list_del(&node
->lower
);
408 if (!RB_EMPTY_NODE(&node
->rb_node
))
409 rb_erase(&node
->rb_node
, &tree
->rb_root
);
410 free_backref_node(tree
, node
);
414 * remove a backref node from the backref cache
416 static void remove_backref_node(struct backref_cache
*cache
,
417 struct backref_node
*node
)
419 struct backref_node
*upper
;
420 struct backref_edge
*edge
;
425 BUG_ON(!node
->lowest
&& !node
->detached
);
426 while (!list_empty(&node
->upper
)) {
427 edge
= list_entry(node
->upper
.next
, struct backref_edge
,
429 upper
= edge
->node
[UPPER
];
430 list_del(&edge
->list
[LOWER
]);
431 list_del(&edge
->list
[UPPER
]);
432 free_backref_edge(cache
, edge
);
434 if (RB_EMPTY_NODE(&upper
->rb_node
)) {
435 BUG_ON(!list_empty(&node
->upper
));
436 drop_backref_node(cache
, node
);
442 * add the node to leaf node list if no other
443 * child block cached.
445 if (list_empty(&upper
->lower
)) {
446 list_add_tail(&upper
->lower
, &cache
->leaves
);
451 drop_backref_node(cache
, node
);
454 static void update_backref_node(struct backref_cache
*cache
,
455 struct backref_node
*node
, u64 bytenr
)
457 struct rb_node
*rb_node
;
458 rb_erase(&node
->rb_node
, &cache
->rb_root
);
459 node
->bytenr
= bytenr
;
460 rb_node
= tree_insert(&cache
->rb_root
, node
->bytenr
, &node
->rb_node
);
462 backref_tree_panic(rb_node
, -EEXIST
, bytenr
);
466 * update backref cache after a transaction commit
468 static int update_backref_cache(struct btrfs_trans_handle
*trans
,
469 struct backref_cache
*cache
)
471 struct backref_node
*node
;
474 if (cache
->last_trans
== 0) {
475 cache
->last_trans
= trans
->transid
;
479 if (cache
->last_trans
== trans
->transid
)
483 * detached nodes are used to avoid unnecessary backref
484 * lookup. transaction commit changes the extent tree.
485 * so the detached nodes are no longer useful.
487 while (!list_empty(&cache
->detached
)) {
488 node
= list_entry(cache
->detached
.next
,
489 struct backref_node
, list
);
490 remove_backref_node(cache
, node
);
493 while (!list_empty(&cache
->changed
)) {
494 node
= list_entry(cache
->changed
.next
,
495 struct backref_node
, list
);
496 list_del_init(&node
->list
);
497 BUG_ON(node
->pending
);
498 update_backref_node(cache
, node
, node
->new_bytenr
);
502 * some nodes can be left in the pending list if there were
503 * errors during processing the pending nodes.
505 for (level
= 0; level
< BTRFS_MAX_LEVEL
; level
++) {
506 list_for_each_entry(node
, &cache
->pending
[level
], list
) {
507 BUG_ON(!node
->pending
);
508 if (node
->bytenr
== node
->new_bytenr
)
510 update_backref_node(cache
, node
, node
->new_bytenr
);
514 cache
->last_trans
= 0;
519 static int should_ignore_root(struct btrfs_root
*root
)
521 struct btrfs_root
*reloc_root
;
523 if (!test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
))
526 reloc_root
= root
->reloc_root
;
530 if (btrfs_root_last_snapshot(&reloc_root
->root_item
) ==
531 root
->fs_info
->running_transaction
->transid
- 1)
534 * if there is reloc tree and it was created in previous
535 * transaction backref lookup can find the reloc tree,
536 * so backref node for the fs tree root is useless for
542 * find reloc tree by address of tree root
544 static struct btrfs_root
*find_reloc_root(struct reloc_control
*rc
,
547 struct rb_node
*rb_node
;
548 struct mapping_node
*node
;
549 struct btrfs_root
*root
= NULL
;
551 spin_lock(&rc
->reloc_root_tree
.lock
);
552 rb_node
= tree_search(&rc
->reloc_root_tree
.rb_root
, bytenr
);
554 node
= rb_entry(rb_node
, struct mapping_node
, rb_node
);
555 root
= (struct btrfs_root
*)node
->data
;
557 spin_unlock(&rc
->reloc_root_tree
.lock
);
561 static int is_cowonly_root(u64 root_objectid
)
563 if (root_objectid
== BTRFS_ROOT_TREE_OBJECTID
||
564 root_objectid
== BTRFS_EXTENT_TREE_OBJECTID
||
565 root_objectid
== BTRFS_CHUNK_TREE_OBJECTID
||
566 root_objectid
== BTRFS_DEV_TREE_OBJECTID
||
567 root_objectid
== BTRFS_TREE_LOG_OBJECTID
||
568 root_objectid
== BTRFS_CSUM_TREE_OBJECTID
||
569 root_objectid
== BTRFS_UUID_TREE_OBJECTID
||
570 root_objectid
== BTRFS_QUOTA_TREE_OBJECTID
||
571 root_objectid
== BTRFS_FREE_SPACE_TREE_OBJECTID
)
576 static struct btrfs_root
*read_fs_root(struct btrfs_fs_info
*fs_info
,
579 struct btrfs_key key
;
581 key
.objectid
= root_objectid
;
582 key
.type
= BTRFS_ROOT_ITEM_KEY
;
583 if (is_cowonly_root(root_objectid
))
586 key
.offset
= (u64
)-1;
588 return btrfs_get_fs_root(fs_info
, &key
, false);
591 static noinline_for_stack
592 int find_inline_backref(struct extent_buffer
*leaf
, int slot
,
593 unsigned long *ptr
, unsigned long *end
)
595 struct btrfs_key key
;
596 struct btrfs_extent_item
*ei
;
597 struct btrfs_tree_block_info
*bi
;
600 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
602 item_size
= btrfs_item_size_nr(leaf
, slot
);
603 if (item_size
< sizeof(*ei
)) {
604 btrfs_print_v0_err(leaf
->fs_info
);
605 btrfs_handle_fs_error(leaf
->fs_info
, -EINVAL
, NULL
);
608 ei
= btrfs_item_ptr(leaf
, slot
, struct btrfs_extent_item
);
609 WARN_ON(!(btrfs_extent_flags(leaf
, ei
) &
610 BTRFS_EXTENT_FLAG_TREE_BLOCK
));
612 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
613 item_size
<= sizeof(*ei
) + sizeof(*bi
)) {
614 WARN_ON(item_size
< sizeof(*ei
) + sizeof(*bi
));
617 if (key
.type
== BTRFS_METADATA_ITEM_KEY
&&
618 item_size
<= sizeof(*ei
)) {
619 WARN_ON(item_size
< sizeof(*ei
));
623 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
) {
624 bi
= (struct btrfs_tree_block_info
*)(ei
+ 1);
625 *ptr
= (unsigned long)(bi
+ 1);
627 *ptr
= (unsigned long)(ei
+ 1);
629 *end
= (unsigned long)ei
+ item_size
;
634 * build backref tree for a given tree block. root of the backref tree
635 * corresponds the tree block, leaves of the backref tree correspond
636 * roots of b-trees that reference the tree block.
638 * the basic idea of this function is check backrefs of a given block
639 * to find upper level blocks that reference the block, and then check
640 * backrefs of these upper level blocks recursively. the recursion stop
641 * when tree root is reached or backrefs for the block is cached.
643 * NOTE: if we find backrefs for a block are cached, we know backrefs
644 * for all upper level blocks that directly/indirectly reference the
645 * block are also cached.
647 static noinline_for_stack
648 struct backref_node
*build_backref_tree(struct reloc_control
*rc
,
649 struct btrfs_key
*node_key
,
650 int level
, u64 bytenr
)
652 struct backref_cache
*cache
= &rc
->backref_cache
;
653 struct btrfs_path
*path1
; /* For searching extent root */
654 struct btrfs_path
*path2
; /* For searching parent of TREE_BLOCK_REF */
655 struct extent_buffer
*eb
;
656 struct btrfs_root
*root
;
657 struct backref_node
*cur
;
658 struct backref_node
*upper
;
659 struct backref_node
*lower
;
660 struct backref_node
*node
= NULL
;
661 struct backref_node
*exist
= NULL
;
662 struct backref_edge
*edge
;
663 struct rb_node
*rb_node
;
664 struct btrfs_key key
;
667 LIST_HEAD(list
); /* Pending edge list, upper node needs to be checked */
672 bool need_check
= true;
674 path1
= btrfs_alloc_path();
675 path2
= btrfs_alloc_path();
676 if (!path1
|| !path2
) {
680 path1
->reada
= READA_FORWARD
;
681 path2
->reada
= READA_FORWARD
;
683 node
= alloc_backref_node(cache
);
689 node
->bytenr
= bytenr
;
696 key
.objectid
= cur
->bytenr
;
697 key
.type
= BTRFS_METADATA_ITEM_KEY
;
698 key
.offset
= (u64
)-1;
700 path1
->search_commit_root
= 1;
701 path1
->skip_locking
= 1;
702 ret
= btrfs_search_slot(NULL
, rc
->extent_root
, &key
, path1
,
709 ASSERT(path1
->slots
[0]);
713 WARN_ON(cur
->checked
);
714 if (!list_empty(&cur
->upper
)) {
716 * the backref was added previously when processing
717 * backref of type BTRFS_TREE_BLOCK_REF_KEY
719 ASSERT(list_is_singular(&cur
->upper
));
720 edge
= list_entry(cur
->upper
.next
, struct backref_edge
,
722 ASSERT(list_empty(&edge
->list
[UPPER
]));
723 exist
= edge
->node
[UPPER
];
725 * add the upper level block to pending list if we need
729 list_add_tail(&edge
->list
[UPPER
], &list
);
736 eb
= path1
->nodes
[0];
739 if (path1
->slots
[0] >= btrfs_header_nritems(eb
)) {
740 ret
= btrfs_next_leaf(rc
->extent_root
, path1
);
747 eb
= path1
->nodes
[0];
750 btrfs_item_key_to_cpu(eb
, &key
, path1
->slots
[0]);
751 if (key
.objectid
!= cur
->bytenr
) {
756 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
||
757 key
.type
== BTRFS_METADATA_ITEM_KEY
) {
758 ret
= find_inline_backref(eb
, path1
->slots
[0],
766 /* update key for inline back ref */
767 struct btrfs_extent_inline_ref
*iref
;
769 iref
= (struct btrfs_extent_inline_ref
*)ptr
;
770 type
= btrfs_get_extent_inline_ref_type(eb
, iref
,
771 BTRFS_REF_TYPE_BLOCK
);
772 if (type
== BTRFS_REF_TYPE_INVALID
) {
777 key
.offset
= btrfs_extent_inline_ref_offset(eb
, iref
);
779 WARN_ON(key
.type
!= BTRFS_TREE_BLOCK_REF_KEY
&&
780 key
.type
!= BTRFS_SHARED_BLOCK_REF_KEY
);
784 * Parent node found and matches current inline ref, no need to
785 * rebuild this node for this inline ref.
788 ((key
.type
== BTRFS_TREE_BLOCK_REF_KEY
&&
789 exist
->owner
== key
.offset
) ||
790 (key
.type
== BTRFS_SHARED_BLOCK_REF_KEY
&&
791 exist
->bytenr
== key
.offset
))) {
796 /* SHARED_BLOCK_REF means key.offset is the parent bytenr */
797 if (key
.type
== BTRFS_SHARED_BLOCK_REF_KEY
) {
798 if (key
.objectid
== key
.offset
) {
800 * Only root blocks of reloc trees use backref
801 * pointing to itself.
803 root
= find_reloc_root(rc
, cur
->bytenr
);
809 edge
= alloc_backref_edge(cache
);
814 rb_node
= tree_search(&cache
->rb_root
, key
.offset
);
816 upper
= alloc_backref_node(cache
);
818 free_backref_edge(cache
, edge
);
822 upper
->bytenr
= key
.offset
;
823 upper
->level
= cur
->level
+ 1;
825 * backrefs for the upper level block isn't
826 * cached, add the block to pending list
828 list_add_tail(&edge
->list
[UPPER
], &list
);
830 upper
= rb_entry(rb_node
, struct backref_node
,
832 ASSERT(upper
->checked
);
833 INIT_LIST_HEAD(&edge
->list
[UPPER
]);
835 list_add_tail(&edge
->list
[LOWER
], &cur
->upper
);
836 edge
->node
[LOWER
] = cur
;
837 edge
->node
[UPPER
] = upper
;
840 } else if (unlikely(key
.type
== BTRFS_EXTENT_REF_V0_KEY
)) {
842 btrfs_print_v0_err(rc
->extent_root
->fs_info
);
843 btrfs_handle_fs_error(rc
->extent_root
->fs_info
, err
,
846 } else if (key
.type
!= BTRFS_TREE_BLOCK_REF_KEY
) {
851 * key.type == BTRFS_TREE_BLOCK_REF_KEY, inline ref offset
852 * means the root objectid. We need to search the tree to get
855 root
= read_fs_root(rc
->extent_root
->fs_info
, key
.offset
);
861 if (!test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
))
864 if (btrfs_root_level(&root
->root_item
) == cur
->level
) {
866 ASSERT(btrfs_root_bytenr(&root
->root_item
) ==
868 if (should_ignore_root(root
))
869 list_add(&cur
->list
, &useless
);
875 level
= cur
->level
+ 1;
877 /* Search the tree to find parent blocks referring the block. */
878 path2
->search_commit_root
= 1;
879 path2
->skip_locking
= 1;
880 path2
->lowest_level
= level
;
881 ret
= btrfs_search_slot(NULL
, root
, node_key
, path2
, 0, 0);
882 path2
->lowest_level
= 0;
887 if (ret
> 0 && path2
->slots
[level
] > 0)
888 path2
->slots
[level
]--;
890 eb
= path2
->nodes
[level
];
891 if (btrfs_node_blockptr(eb
, path2
->slots
[level
]) !=
893 btrfs_err(root
->fs_info
,
894 "couldn't find block (%llu) (level %d) in tree (%llu) with key (%llu %u %llu)",
895 cur
->bytenr
, level
- 1,
896 root
->root_key
.objectid
,
897 node_key
->objectid
, node_key
->type
,
905 /* Add all nodes and edges in the path */
906 for (; level
< BTRFS_MAX_LEVEL
; level
++) {
907 if (!path2
->nodes
[level
]) {
908 ASSERT(btrfs_root_bytenr(&root
->root_item
) ==
910 if (should_ignore_root(root
))
911 list_add(&lower
->list
, &useless
);
917 edge
= alloc_backref_edge(cache
);
923 eb
= path2
->nodes
[level
];
924 rb_node
= tree_search(&cache
->rb_root
, eb
->start
);
926 upper
= alloc_backref_node(cache
);
928 free_backref_edge(cache
, edge
);
932 upper
->bytenr
= eb
->start
;
933 upper
->owner
= btrfs_header_owner(eb
);
934 upper
->level
= lower
->level
+ 1;
935 if (!test_bit(BTRFS_ROOT_REF_COWS
,
940 * if we know the block isn't shared
941 * we can void checking its backrefs.
943 if (btrfs_block_can_be_shared(root
, eb
))
949 * add the block to pending list if we
950 * need check its backrefs, we only do this once
951 * while walking up a tree as we will catch
952 * anything else later on.
954 if (!upper
->checked
&& need_check
) {
956 list_add_tail(&edge
->list
[UPPER
],
961 INIT_LIST_HEAD(&edge
->list
[UPPER
]);
964 upper
= rb_entry(rb_node
, struct backref_node
,
966 ASSERT(upper
->checked
);
967 INIT_LIST_HEAD(&edge
->list
[UPPER
]);
969 upper
->owner
= btrfs_header_owner(eb
);
971 list_add_tail(&edge
->list
[LOWER
], &lower
->upper
);
972 edge
->node
[LOWER
] = lower
;
973 edge
->node
[UPPER
] = upper
;
980 btrfs_release_path(path2
);
983 ptr
+= btrfs_extent_inline_ref_size(key
.type
);
993 btrfs_release_path(path1
);
998 /* the pending list isn't empty, take the first block to process */
999 if (!list_empty(&list
)) {
1000 edge
= list_entry(list
.next
, struct backref_edge
, list
[UPPER
]);
1001 list_del_init(&edge
->list
[UPPER
]);
1002 cur
= edge
->node
[UPPER
];
1007 * everything goes well, connect backref nodes and insert backref nodes
1010 ASSERT(node
->checked
);
1011 cowonly
= node
->cowonly
;
1013 rb_node
= tree_insert(&cache
->rb_root
, node
->bytenr
,
1016 backref_tree_panic(rb_node
, -EEXIST
, node
->bytenr
);
1017 list_add_tail(&node
->lower
, &cache
->leaves
);
1020 list_for_each_entry(edge
, &node
->upper
, list
[LOWER
])
1021 list_add_tail(&edge
->list
[UPPER
], &list
);
1023 while (!list_empty(&list
)) {
1024 edge
= list_entry(list
.next
, struct backref_edge
, list
[UPPER
]);
1025 list_del_init(&edge
->list
[UPPER
]);
1026 upper
= edge
->node
[UPPER
];
1027 if (upper
->detached
) {
1028 list_del(&edge
->list
[LOWER
]);
1029 lower
= edge
->node
[LOWER
];
1030 free_backref_edge(cache
, edge
);
1031 if (list_empty(&lower
->upper
))
1032 list_add(&lower
->list
, &useless
);
1036 if (!RB_EMPTY_NODE(&upper
->rb_node
)) {
1037 if (upper
->lowest
) {
1038 list_del_init(&upper
->lower
);
1042 list_add_tail(&edge
->list
[UPPER
], &upper
->lower
);
1046 if (!upper
->checked
) {
1048 * Still want to blow up for developers since this is a
1055 if (cowonly
!= upper
->cowonly
) {
1062 rb_node
= tree_insert(&cache
->rb_root
, upper
->bytenr
,
1065 backref_tree_panic(rb_node
, -EEXIST
,
1069 list_add_tail(&edge
->list
[UPPER
], &upper
->lower
);
1071 list_for_each_entry(edge
, &upper
->upper
, list
[LOWER
])
1072 list_add_tail(&edge
->list
[UPPER
], &list
);
1075 * process useless backref nodes. backref nodes for tree leaves
1076 * are deleted from the cache. backref nodes for upper level
1077 * tree blocks are left in the cache to avoid unnecessary backref
1080 while (!list_empty(&useless
)) {
1081 upper
= list_entry(useless
.next
, struct backref_node
, list
);
1082 list_del_init(&upper
->list
);
1083 ASSERT(list_empty(&upper
->upper
));
1086 if (upper
->lowest
) {
1087 list_del_init(&upper
->lower
);
1090 while (!list_empty(&upper
->lower
)) {
1091 edge
= list_entry(upper
->lower
.next
,
1092 struct backref_edge
, list
[UPPER
]);
1093 list_del(&edge
->list
[UPPER
]);
1094 list_del(&edge
->list
[LOWER
]);
1095 lower
= edge
->node
[LOWER
];
1096 free_backref_edge(cache
, edge
);
1098 if (list_empty(&lower
->upper
))
1099 list_add(&lower
->list
, &useless
);
1101 __mark_block_processed(rc
, upper
);
1102 if (upper
->level
> 0) {
1103 list_add(&upper
->list
, &cache
->detached
);
1104 upper
->detached
= 1;
1106 rb_erase(&upper
->rb_node
, &cache
->rb_root
);
1107 free_backref_node(cache
, upper
);
1111 btrfs_free_path(path1
);
1112 btrfs_free_path(path2
);
1114 while (!list_empty(&useless
)) {
1115 lower
= list_entry(useless
.next
,
1116 struct backref_node
, list
);
1117 list_del_init(&lower
->list
);
1119 while (!list_empty(&list
)) {
1120 edge
= list_first_entry(&list
, struct backref_edge
,
1122 list_del(&edge
->list
[UPPER
]);
1123 list_del(&edge
->list
[LOWER
]);
1124 lower
= edge
->node
[LOWER
];
1125 upper
= edge
->node
[UPPER
];
1126 free_backref_edge(cache
, edge
);
1129 * Lower is no longer linked to any upper backref nodes
1130 * and isn't in the cache, we can free it ourselves.
1132 if (list_empty(&lower
->upper
) &&
1133 RB_EMPTY_NODE(&lower
->rb_node
))
1134 list_add(&lower
->list
, &useless
);
1136 if (!RB_EMPTY_NODE(&upper
->rb_node
))
1139 /* Add this guy's upper edges to the list to process */
1140 list_for_each_entry(edge
, &upper
->upper
, list
[LOWER
])
1141 list_add_tail(&edge
->list
[UPPER
], &list
);
1142 if (list_empty(&upper
->upper
))
1143 list_add(&upper
->list
, &useless
);
1146 while (!list_empty(&useless
)) {
1147 lower
= list_entry(useless
.next
,
1148 struct backref_node
, list
);
1149 list_del_init(&lower
->list
);
1152 free_backref_node(cache
, lower
);
1155 free_backref_node(cache
, node
);
1156 return ERR_PTR(err
);
1158 ASSERT(!node
|| !node
->detached
);
1163 * helper to add backref node for the newly created snapshot.
1164 * the backref node is created by cloning backref node that
1165 * corresponds to root of source tree
1167 static int clone_backref_node(struct btrfs_trans_handle
*trans
,
1168 struct reloc_control
*rc
,
1169 struct btrfs_root
*src
,
1170 struct btrfs_root
*dest
)
1172 struct btrfs_root
*reloc_root
= src
->reloc_root
;
1173 struct backref_cache
*cache
= &rc
->backref_cache
;
1174 struct backref_node
*node
= NULL
;
1175 struct backref_node
*new_node
;
1176 struct backref_edge
*edge
;
1177 struct backref_edge
*new_edge
;
1178 struct rb_node
*rb_node
;
1180 if (cache
->last_trans
> 0)
1181 update_backref_cache(trans
, cache
);
1183 rb_node
= tree_search(&cache
->rb_root
, src
->commit_root
->start
);
1185 node
= rb_entry(rb_node
, struct backref_node
, rb_node
);
1189 BUG_ON(node
->new_bytenr
!= reloc_root
->node
->start
);
1193 rb_node
= tree_search(&cache
->rb_root
,
1194 reloc_root
->commit_root
->start
);
1196 node
= rb_entry(rb_node
, struct backref_node
,
1198 BUG_ON(node
->detached
);
1205 new_node
= alloc_backref_node(cache
);
1209 new_node
->bytenr
= dest
->node
->start
;
1210 new_node
->level
= node
->level
;
1211 new_node
->lowest
= node
->lowest
;
1212 new_node
->checked
= 1;
1213 new_node
->root
= dest
;
1215 if (!node
->lowest
) {
1216 list_for_each_entry(edge
, &node
->lower
, list
[UPPER
]) {
1217 new_edge
= alloc_backref_edge(cache
);
1221 new_edge
->node
[UPPER
] = new_node
;
1222 new_edge
->node
[LOWER
] = edge
->node
[LOWER
];
1223 list_add_tail(&new_edge
->list
[UPPER
],
1227 list_add_tail(&new_node
->lower
, &cache
->leaves
);
1230 rb_node
= tree_insert(&cache
->rb_root
, new_node
->bytenr
,
1231 &new_node
->rb_node
);
1233 backref_tree_panic(rb_node
, -EEXIST
, new_node
->bytenr
);
1235 if (!new_node
->lowest
) {
1236 list_for_each_entry(new_edge
, &new_node
->lower
, list
[UPPER
]) {
1237 list_add_tail(&new_edge
->list
[LOWER
],
1238 &new_edge
->node
[LOWER
]->upper
);
1243 while (!list_empty(&new_node
->lower
)) {
1244 new_edge
= list_entry(new_node
->lower
.next
,
1245 struct backref_edge
, list
[UPPER
]);
1246 list_del(&new_edge
->list
[UPPER
]);
1247 free_backref_edge(cache
, new_edge
);
1249 free_backref_node(cache
, new_node
);
1254 * helper to add 'address of tree root -> reloc tree' mapping
1256 static int __must_check
__add_reloc_root(struct btrfs_root
*root
)
1258 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1259 struct rb_node
*rb_node
;
1260 struct mapping_node
*node
;
1261 struct reloc_control
*rc
= fs_info
->reloc_ctl
;
1263 node
= kmalloc(sizeof(*node
), GFP_NOFS
);
1267 node
->bytenr
= root
->node
->start
;
1270 spin_lock(&rc
->reloc_root_tree
.lock
);
1271 rb_node
= tree_insert(&rc
->reloc_root_tree
.rb_root
,
1272 node
->bytenr
, &node
->rb_node
);
1273 spin_unlock(&rc
->reloc_root_tree
.lock
);
1275 btrfs_panic(fs_info
, -EEXIST
,
1276 "Duplicate root found for start=%llu while inserting into relocation tree",
1280 list_add_tail(&root
->root_list
, &rc
->reloc_roots
);
1285 * helper to delete the 'address of tree root -> reloc tree'
1288 static void __del_reloc_root(struct btrfs_root
*root
)
1290 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1291 struct rb_node
*rb_node
;
1292 struct mapping_node
*node
= NULL
;
1293 struct reloc_control
*rc
= fs_info
->reloc_ctl
;
1295 if (rc
&& root
->node
) {
1296 spin_lock(&rc
->reloc_root_tree
.lock
);
1297 rb_node
= tree_search(&rc
->reloc_root_tree
.rb_root
,
1300 node
= rb_entry(rb_node
, struct mapping_node
, rb_node
);
1301 rb_erase(&node
->rb_node
, &rc
->reloc_root_tree
.rb_root
);
1303 spin_unlock(&rc
->reloc_root_tree
.lock
);
1306 BUG_ON((struct btrfs_root
*)node
->data
!= root
);
1309 spin_lock(&fs_info
->trans_lock
);
1310 list_del_init(&root
->root_list
);
1311 spin_unlock(&fs_info
->trans_lock
);
1316 * helper to update the 'address of tree root -> reloc tree'
1319 static int __update_reloc_root(struct btrfs_root
*root
, u64 new_bytenr
)
1321 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1322 struct rb_node
*rb_node
;
1323 struct mapping_node
*node
= NULL
;
1324 struct reloc_control
*rc
= fs_info
->reloc_ctl
;
1326 spin_lock(&rc
->reloc_root_tree
.lock
);
1327 rb_node
= tree_search(&rc
->reloc_root_tree
.rb_root
,
1330 node
= rb_entry(rb_node
, struct mapping_node
, rb_node
);
1331 rb_erase(&node
->rb_node
, &rc
->reloc_root_tree
.rb_root
);
1333 spin_unlock(&rc
->reloc_root_tree
.lock
);
1337 BUG_ON((struct btrfs_root
*)node
->data
!= root
);
1339 spin_lock(&rc
->reloc_root_tree
.lock
);
1340 node
->bytenr
= new_bytenr
;
1341 rb_node
= tree_insert(&rc
->reloc_root_tree
.rb_root
,
1342 node
->bytenr
, &node
->rb_node
);
1343 spin_unlock(&rc
->reloc_root_tree
.lock
);
1345 backref_tree_panic(rb_node
, -EEXIST
, node
->bytenr
);
1349 static struct btrfs_root
*create_reloc_root(struct btrfs_trans_handle
*trans
,
1350 struct btrfs_root
*root
, u64 objectid
)
1352 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1353 struct btrfs_root
*reloc_root
;
1354 struct extent_buffer
*eb
;
1355 struct btrfs_root_item
*root_item
;
1356 struct btrfs_key root_key
;
1359 root_item
= kmalloc(sizeof(*root_item
), GFP_NOFS
);
1362 root_key
.objectid
= BTRFS_TREE_RELOC_OBJECTID
;
1363 root_key
.type
= BTRFS_ROOT_ITEM_KEY
;
1364 root_key
.offset
= objectid
;
1366 if (root
->root_key
.objectid
== objectid
) {
1367 u64 commit_root_gen
;
1369 /* called by btrfs_init_reloc_root */
1370 ret
= btrfs_copy_root(trans
, root
, root
->commit_root
, &eb
,
1371 BTRFS_TREE_RELOC_OBJECTID
);
1374 * Set the last_snapshot field to the generation of the commit
1375 * root - like this ctree.c:btrfs_block_can_be_shared() behaves
1376 * correctly (returns true) when the relocation root is created
1377 * either inside the critical section of a transaction commit
1378 * (through transaction.c:qgroup_account_snapshot()) and when
1379 * it's created before the transaction commit is started.
1381 commit_root_gen
= btrfs_header_generation(root
->commit_root
);
1382 btrfs_set_root_last_snapshot(&root
->root_item
, commit_root_gen
);
1385 * called by btrfs_reloc_post_snapshot_hook.
1386 * the source tree is a reloc tree, all tree blocks
1387 * modified after it was created have RELOC flag
1388 * set in their headers. so it's OK to not update
1389 * the 'last_snapshot'.
1391 ret
= btrfs_copy_root(trans
, root
, root
->node
, &eb
,
1392 BTRFS_TREE_RELOC_OBJECTID
);
1396 memcpy(root_item
, &root
->root_item
, sizeof(*root_item
));
1397 btrfs_set_root_bytenr(root_item
, eb
->start
);
1398 btrfs_set_root_level(root_item
, btrfs_header_level(eb
));
1399 btrfs_set_root_generation(root_item
, trans
->transid
);
1401 if (root
->root_key
.objectid
== objectid
) {
1402 btrfs_set_root_refs(root_item
, 0);
1403 memset(&root_item
->drop_progress
, 0,
1404 sizeof(struct btrfs_disk_key
));
1405 root_item
->drop_level
= 0;
1408 btrfs_tree_unlock(eb
);
1409 free_extent_buffer(eb
);
1411 ret
= btrfs_insert_root(trans
, fs_info
->tree_root
,
1412 &root_key
, root_item
);
1416 reloc_root
= btrfs_read_fs_root(fs_info
->tree_root
, &root_key
);
1417 BUG_ON(IS_ERR(reloc_root
));
1418 reloc_root
->last_trans
= trans
->transid
;
1423 * create reloc tree for a given fs tree. reloc tree is just a
1424 * snapshot of the fs tree with special root objectid.
1426 int btrfs_init_reloc_root(struct btrfs_trans_handle
*trans
,
1427 struct btrfs_root
*root
)
1429 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1430 struct btrfs_root
*reloc_root
;
1431 struct reloc_control
*rc
= fs_info
->reloc_ctl
;
1432 struct btrfs_block_rsv
*rsv
;
1436 if (root
->reloc_root
) {
1437 reloc_root
= root
->reloc_root
;
1438 reloc_root
->last_trans
= trans
->transid
;
1442 if (!rc
|| !rc
->create_reloc_tree
||
1443 root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
)
1446 if (!trans
->reloc_reserved
) {
1447 rsv
= trans
->block_rsv
;
1448 trans
->block_rsv
= rc
->block_rsv
;
1451 reloc_root
= create_reloc_root(trans
, root
, root
->root_key
.objectid
);
1453 trans
->block_rsv
= rsv
;
1455 ret
= __add_reloc_root(reloc_root
);
1457 root
->reloc_root
= reloc_root
;
1462 * update root item of reloc tree
1464 int btrfs_update_reloc_root(struct btrfs_trans_handle
*trans
,
1465 struct btrfs_root
*root
)
1467 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1468 struct btrfs_root
*reloc_root
;
1469 struct btrfs_root_item
*root_item
;
1472 if (test_bit(BTRFS_ROOT_DEAD_RELOC_TREE
, &root
->state
) ||
1476 reloc_root
= root
->reloc_root
;
1477 root_item
= &reloc_root
->root_item
;
1479 /* root->reloc_root will stay until current relocation finished */
1480 if (fs_info
->reloc_ctl
->merge_reloc_tree
&&
1481 btrfs_root_refs(root_item
) == 0) {
1482 set_bit(BTRFS_ROOT_DEAD_RELOC_TREE
, &root
->state
);
1483 __del_reloc_root(reloc_root
);
1486 if (reloc_root
->commit_root
!= reloc_root
->node
) {
1487 btrfs_set_root_node(root_item
, reloc_root
->node
);
1488 free_extent_buffer(reloc_root
->commit_root
);
1489 reloc_root
->commit_root
= btrfs_root_node(reloc_root
);
1492 ret
= btrfs_update_root(trans
, fs_info
->tree_root
,
1493 &reloc_root
->root_key
, root_item
);
1501 * helper to find first cached inode with inode number >= objectid
1504 static struct inode
*find_next_inode(struct btrfs_root
*root
, u64 objectid
)
1506 struct rb_node
*node
;
1507 struct rb_node
*prev
;
1508 struct btrfs_inode
*entry
;
1509 struct inode
*inode
;
1511 spin_lock(&root
->inode_lock
);
1513 node
= root
->inode_tree
.rb_node
;
1517 entry
= rb_entry(node
, struct btrfs_inode
, rb_node
);
1519 if (objectid
< btrfs_ino(entry
))
1520 node
= node
->rb_left
;
1521 else if (objectid
> btrfs_ino(entry
))
1522 node
= node
->rb_right
;
1528 entry
= rb_entry(prev
, struct btrfs_inode
, rb_node
);
1529 if (objectid
<= btrfs_ino(entry
)) {
1533 prev
= rb_next(prev
);
1537 entry
= rb_entry(node
, struct btrfs_inode
, rb_node
);
1538 inode
= igrab(&entry
->vfs_inode
);
1540 spin_unlock(&root
->inode_lock
);
1544 objectid
= btrfs_ino(entry
) + 1;
1545 if (cond_resched_lock(&root
->inode_lock
))
1548 node
= rb_next(node
);
1550 spin_unlock(&root
->inode_lock
);
1554 static int in_block_group(u64 bytenr
,
1555 struct btrfs_block_group_cache
*block_group
)
1557 if (bytenr
>= block_group
->key
.objectid
&&
1558 bytenr
< block_group
->key
.objectid
+ block_group
->key
.offset
)
1564 * get new location of data
1566 static int get_new_location(struct inode
*reloc_inode
, u64
*new_bytenr
,
1567 u64 bytenr
, u64 num_bytes
)
1569 struct btrfs_root
*root
= BTRFS_I(reloc_inode
)->root
;
1570 struct btrfs_path
*path
;
1571 struct btrfs_file_extent_item
*fi
;
1572 struct extent_buffer
*leaf
;
1575 path
= btrfs_alloc_path();
1579 bytenr
-= BTRFS_I(reloc_inode
)->index_cnt
;
1580 ret
= btrfs_lookup_file_extent(NULL
, root
, path
,
1581 btrfs_ino(BTRFS_I(reloc_inode
)), bytenr
, 0);
1589 leaf
= path
->nodes
[0];
1590 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1591 struct btrfs_file_extent_item
);
1593 BUG_ON(btrfs_file_extent_offset(leaf
, fi
) ||
1594 btrfs_file_extent_compression(leaf
, fi
) ||
1595 btrfs_file_extent_encryption(leaf
, fi
) ||
1596 btrfs_file_extent_other_encoding(leaf
, fi
));
1598 if (num_bytes
!= btrfs_file_extent_disk_num_bytes(leaf
, fi
)) {
1603 *new_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1606 btrfs_free_path(path
);
1611 * update file extent items in the tree leaf to point to
1612 * the new locations.
1614 static noinline_for_stack
1615 int replace_file_extents(struct btrfs_trans_handle
*trans
,
1616 struct reloc_control
*rc
,
1617 struct btrfs_root
*root
,
1618 struct extent_buffer
*leaf
)
1620 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1621 struct btrfs_key key
;
1622 struct btrfs_file_extent_item
*fi
;
1623 struct inode
*inode
= NULL
;
1635 if (rc
->stage
!= UPDATE_DATA_PTRS
)
1638 /* reloc trees always use full backref */
1639 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
)
1640 parent
= leaf
->start
;
1644 nritems
= btrfs_header_nritems(leaf
);
1645 for (i
= 0; i
< nritems
; i
++) {
1647 btrfs_item_key_to_cpu(leaf
, &key
, i
);
1648 if (key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1650 fi
= btrfs_item_ptr(leaf
, i
, struct btrfs_file_extent_item
);
1651 if (btrfs_file_extent_type(leaf
, fi
) ==
1652 BTRFS_FILE_EXTENT_INLINE
)
1654 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1655 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1658 if (!in_block_group(bytenr
, rc
->block_group
))
1662 * if we are modifying block in fs tree, wait for readpage
1663 * to complete and drop the extent cache
1665 if (root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
) {
1667 inode
= find_next_inode(root
, key
.objectid
);
1669 } else if (inode
&& btrfs_ino(BTRFS_I(inode
)) < key
.objectid
) {
1670 btrfs_add_delayed_iput(inode
);
1671 inode
= find_next_inode(root
, key
.objectid
);
1673 if (inode
&& btrfs_ino(BTRFS_I(inode
)) == key
.objectid
) {
1675 btrfs_file_extent_num_bytes(leaf
, fi
);
1676 WARN_ON(!IS_ALIGNED(key
.offset
,
1677 fs_info
->sectorsize
));
1678 WARN_ON(!IS_ALIGNED(end
, fs_info
->sectorsize
));
1680 ret
= try_lock_extent(&BTRFS_I(inode
)->io_tree
,
1685 btrfs_drop_extent_cache(BTRFS_I(inode
),
1686 key
.offset
, end
, 1);
1687 unlock_extent(&BTRFS_I(inode
)->io_tree
,
1692 ret
= get_new_location(rc
->data_inode
, &new_bytenr
,
1696 * Don't have to abort since we've not changed anything
1697 * in the file extent yet.
1702 btrfs_set_file_extent_disk_bytenr(leaf
, fi
, new_bytenr
);
1705 key
.offset
-= btrfs_file_extent_offset(leaf
, fi
);
1706 ret
= btrfs_inc_extent_ref(trans
, root
, new_bytenr
,
1708 btrfs_header_owner(leaf
),
1709 key
.objectid
, key
.offset
);
1711 btrfs_abort_transaction(trans
, ret
);
1715 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1716 parent
, btrfs_header_owner(leaf
),
1717 key
.objectid
, key
.offset
);
1719 btrfs_abort_transaction(trans
, ret
);
1724 btrfs_mark_buffer_dirty(leaf
);
1726 btrfs_add_delayed_iput(inode
);
1730 static noinline_for_stack
1731 int memcmp_node_keys(struct extent_buffer
*eb
, int slot
,
1732 struct btrfs_path
*path
, int level
)
1734 struct btrfs_disk_key key1
;
1735 struct btrfs_disk_key key2
;
1736 btrfs_node_key(eb
, &key1
, slot
);
1737 btrfs_node_key(path
->nodes
[level
], &key2
, path
->slots
[level
]);
1738 return memcmp(&key1
, &key2
, sizeof(key1
));
1742 * try to replace tree blocks in fs tree with the new blocks
1743 * in reloc tree. tree blocks haven't been modified since the
1744 * reloc tree was create can be replaced.
1746 * if a block was replaced, level of the block + 1 is returned.
1747 * if no block got replaced, 0 is returned. if there are other
1748 * errors, a negative error number is returned.
1750 static noinline_for_stack
1751 int replace_path(struct btrfs_trans_handle
*trans
, struct reloc_control
*rc
,
1752 struct btrfs_root
*dest
, struct btrfs_root
*src
,
1753 struct btrfs_path
*path
, struct btrfs_key
*next_key
,
1754 int lowest_level
, int max_level
)
1756 struct btrfs_fs_info
*fs_info
= dest
->fs_info
;
1757 struct extent_buffer
*eb
;
1758 struct extent_buffer
*parent
;
1759 struct btrfs_key key
;
1771 BUG_ON(src
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
);
1772 BUG_ON(dest
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
);
1774 last_snapshot
= btrfs_root_last_snapshot(&src
->root_item
);
1776 slot
= path
->slots
[lowest_level
];
1777 btrfs_node_key_to_cpu(path
->nodes
[lowest_level
], &key
, slot
);
1779 eb
= btrfs_lock_root_node(dest
);
1780 btrfs_set_lock_blocking_write(eb
);
1781 level
= btrfs_header_level(eb
);
1783 if (level
< lowest_level
) {
1784 btrfs_tree_unlock(eb
);
1785 free_extent_buffer(eb
);
1790 ret
= btrfs_cow_block(trans
, dest
, eb
, NULL
, 0, &eb
);
1793 btrfs_set_lock_blocking_write(eb
);
1796 next_key
->objectid
= (u64
)-1;
1797 next_key
->type
= (u8
)-1;
1798 next_key
->offset
= (u64
)-1;
1803 struct btrfs_key first_key
;
1805 level
= btrfs_header_level(parent
);
1806 BUG_ON(level
< lowest_level
);
1808 ret
= btrfs_bin_search(parent
, &key
, level
, &slot
);
1811 if (ret
&& slot
> 0)
1814 if (next_key
&& slot
+ 1 < btrfs_header_nritems(parent
))
1815 btrfs_node_key_to_cpu(parent
, next_key
, slot
+ 1);
1817 old_bytenr
= btrfs_node_blockptr(parent
, slot
);
1818 blocksize
= fs_info
->nodesize
;
1819 old_ptr_gen
= btrfs_node_ptr_generation(parent
, slot
);
1820 btrfs_node_key_to_cpu(parent
, &first_key
, slot
);
1822 if (level
<= max_level
) {
1823 eb
= path
->nodes
[level
];
1824 new_bytenr
= btrfs_node_blockptr(eb
,
1825 path
->slots
[level
]);
1826 new_ptr_gen
= btrfs_node_ptr_generation(eb
,
1827 path
->slots
[level
]);
1833 if (WARN_ON(new_bytenr
> 0 && new_bytenr
== old_bytenr
)) {
1838 if (new_bytenr
== 0 || old_ptr_gen
> last_snapshot
||
1839 memcmp_node_keys(parent
, slot
, path
, level
)) {
1840 if (level
<= lowest_level
) {
1845 eb
= read_tree_block(fs_info
, old_bytenr
, old_ptr_gen
,
1846 level
- 1, &first_key
);
1850 } else if (!extent_buffer_uptodate(eb
)) {
1852 free_extent_buffer(eb
);
1855 btrfs_tree_lock(eb
);
1857 ret
= btrfs_cow_block(trans
, dest
, eb
, parent
,
1861 btrfs_set_lock_blocking_write(eb
);
1863 btrfs_tree_unlock(parent
);
1864 free_extent_buffer(parent
);
1871 btrfs_tree_unlock(parent
);
1872 free_extent_buffer(parent
);
1877 btrfs_node_key_to_cpu(path
->nodes
[level
], &key
,
1878 path
->slots
[level
]);
1879 btrfs_release_path(path
);
1881 path
->lowest_level
= level
;
1882 ret
= btrfs_search_slot(trans
, src
, &key
, path
, 0, 1);
1883 path
->lowest_level
= 0;
1887 * Info qgroup to trace both subtrees.
1889 * We must trace both trees.
1890 * 1) Tree reloc subtree
1891 * If not traced, we will leak data numbers
1893 * If not traced, we will double count old data
1895 * We don't scan the subtree right now, but only record
1896 * the swapped tree blocks.
1897 * The real subtree rescan is delayed until we have new
1898 * CoW on the subtree root node before transaction commit.
1900 ret
= btrfs_qgroup_add_swapped_blocks(trans
, dest
,
1901 rc
->block_group
, parent
, slot
,
1902 path
->nodes
[level
], path
->slots
[level
],
1907 * swap blocks in fs tree and reloc tree.
1909 btrfs_set_node_blockptr(parent
, slot
, new_bytenr
);
1910 btrfs_set_node_ptr_generation(parent
, slot
, new_ptr_gen
);
1911 btrfs_mark_buffer_dirty(parent
);
1913 btrfs_set_node_blockptr(path
->nodes
[level
],
1914 path
->slots
[level
], old_bytenr
);
1915 btrfs_set_node_ptr_generation(path
->nodes
[level
],
1916 path
->slots
[level
], old_ptr_gen
);
1917 btrfs_mark_buffer_dirty(path
->nodes
[level
]);
1919 ret
= btrfs_inc_extent_ref(trans
, src
, old_bytenr
,
1920 blocksize
, path
->nodes
[level
]->start
,
1921 src
->root_key
.objectid
, level
- 1, 0);
1923 ret
= btrfs_inc_extent_ref(trans
, dest
, new_bytenr
,
1924 blocksize
, 0, dest
->root_key
.objectid
,
1928 ret
= btrfs_free_extent(trans
, src
, new_bytenr
, blocksize
,
1929 path
->nodes
[level
]->start
,
1930 src
->root_key
.objectid
, level
- 1, 0);
1933 ret
= btrfs_free_extent(trans
, dest
, old_bytenr
, blocksize
,
1934 0, dest
->root_key
.objectid
, level
- 1,
1938 btrfs_unlock_up_safe(path
, 0);
1943 btrfs_tree_unlock(parent
);
1944 free_extent_buffer(parent
);
1949 * helper to find next relocated block in reloc tree
1951 static noinline_for_stack
1952 int walk_up_reloc_tree(struct btrfs_root
*root
, struct btrfs_path
*path
,
1955 struct extent_buffer
*eb
;
1960 last_snapshot
= btrfs_root_last_snapshot(&root
->root_item
);
1962 for (i
= 0; i
< *level
; i
++) {
1963 free_extent_buffer(path
->nodes
[i
]);
1964 path
->nodes
[i
] = NULL
;
1967 for (i
= *level
; i
< BTRFS_MAX_LEVEL
&& path
->nodes
[i
]; i
++) {
1968 eb
= path
->nodes
[i
];
1969 nritems
= btrfs_header_nritems(eb
);
1970 while (path
->slots
[i
] + 1 < nritems
) {
1972 if (btrfs_node_ptr_generation(eb
, path
->slots
[i
]) <=
1979 free_extent_buffer(path
->nodes
[i
]);
1980 path
->nodes
[i
] = NULL
;
1986 * walk down reloc tree to find relocated block of lowest level
1988 static noinline_for_stack
1989 int walk_down_reloc_tree(struct btrfs_root
*root
, struct btrfs_path
*path
,
1992 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
1993 struct extent_buffer
*eb
= NULL
;
2000 last_snapshot
= btrfs_root_last_snapshot(&root
->root_item
);
2002 for (i
= *level
; i
> 0; i
--) {
2003 struct btrfs_key first_key
;
2005 eb
= path
->nodes
[i
];
2006 nritems
= btrfs_header_nritems(eb
);
2007 while (path
->slots
[i
] < nritems
) {
2008 ptr_gen
= btrfs_node_ptr_generation(eb
, path
->slots
[i
]);
2009 if (ptr_gen
> last_snapshot
)
2013 if (path
->slots
[i
] >= nritems
) {
2024 bytenr
= btrfs_node_blockptr(eb
, path
->slots
[i
]);
2025 btrfs_node_key_to_cpu(eb
, &first_key
, path
->slots
[i
]);
2026 eb
= read_tree_block(fs_info
, bytenr
, ptr_gen
, i
- 1,
2030 } else if (!extent_buffer_uptodate(eb
)) {
2031 free_extent_buffer(eb
);
2034 BUG_ON(btrfs_header_level(eb
) != i
- 1);
2035 path
->nodes
[i
- 1] = eb
;
2036 path
->slots
[i
- 1] = 0;
2042 * invalidate extent cache for file extents whose key in range of
2043 * [min_key, max_key)
2045 static int invalidate_extent_cache(struct btrfs_root
*root
,
2046 struct btrfs_key
*min_key
,
2047 struct btrfs_key
*max_key
)
2049 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
2050 struct inode
*inode
= NULL
;
2055 objectid
= min_key
->objectid
;
2060 if (objectid
> max_key
->objectid
)
2063 inode
= find_next_inode(root
, objectid
);
2066 ino
= btrfs_ino(BTRFS_I(inode
));
2068 if (ino
> max_key
->objectid
) {
2074 if (!S_ISREG(inode
->i_mode
))
2077 if (unlikely(min_key
->objectid
== ino
)) {
2078 if (min_key
->type
> BTRFS_EXTENT_DATA_KEY
)
2080 if (min_key
->type
< BTRFS_EXTENT_DATA_KEY
)
2083 start
= min_key
->offset
;
2084 WARN_ON(!IS_ALIGNED(start
, fs_info
->sectorsize
));
2090 if (unlikely(max_key
->objectid
== ino
)) {
2091 if (max_key
->type
< BTRFS_EXTENT_DATA_KEY
)
2093 if (max_key
->type
> BTRFS_EXTENT_DATA_KEY
) {
2096 if (max_key
->offset
== 0)
2098 end
= max_key
->offset
;
2099 WARN_ON(!IS_ALIGNED(end
, fs_info
->sectorsize
));
2106 /* the lock_extent waits for readpage to complete */
2107 lock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
2108 btrfs_drop_extent_cache(BTRFS_I(inode
), start
, end
, 1);
2109 unlock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
2114 static int find_next_key(struct btrfs_path
*path
, int level
,
2115 struct btrfs_key
*key
)
2118 while (level
< BTRFS_MAX_LEVEL
) {
2119 if (!path
->nodes
[level
])
2121 if (path
->slots
[level
] + 1 <
2122 btrfs_header_nritems(path
->nodes
[level
])) {
2123 btrfs_node_key_to_cpu(path
->nodes
[level
], key
,
2124 path
->slots
[level
] + 1);
2133 * Insert current subvolume into reloc_control::dirty_subvol_roots
2135 static void insert_dirty_subvol(struct btrfs_trans_handle
*trans
,
2136 struct reloc_control
*rc
,
2137 struct btrfs_root
*root
)
2139 struct btrfs_root
*reloc_root
= root
->reloc_root
;
2140 struct btrfs_root_item
*reloc_root_item
;
2142 /* @root must be a subvolume tree root with a valid reloc tree */
2143 ASSERT(root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
);
2146 reloc_root_item
= &reloc_root
->root_item
;
2147 memset(&reloc_root_item
->drop_progress
, 0,
2148 sizeof(reloc_root_item
->drop_progress
));
2149 reloc_root_item
->drop_level
= 0;
2150 btrfs_set_root_refs(reloc_root_item
, 0);
2151 btrfs_update_reloc_root(trans
, root
);
2153 if (list_empty(&root
->reloc_dirty_list
)) {
2154 btrfs_grab_fs_root(root
);
2155 list_add_tail(&root
->reloc_dirty_list
, &rc
->dirty_subvol_roots
);
2159 static int clean_dirty_subvols(struct reloc_control
*rc
)
2161 struct btrfs_root
*root
;
2162 struct btrfs_root
*next
;
2165 list_for_each_entry_safe(root
, next
, &rc
->dirty_subvol_roots
,
2167 struct btrfs_root
*reloc_root
= root
->reloc_root
;
2169 clear_bit(BTRFS_ROOT_DEAD_RELOC_TREE
, &root
->state
);
2170 list_del_init(&root
->reloc_dirty_list
);
2171 root
->reloc_root
= NULL
;
2175 ret2
= btrfs_drop_snapshot(reloc_root
, NULL
, 0, 1);
2176 if (ret2
< 0 && !ret
)
2179 btrfs_put_fs_root(root
);
2185 * merge the relocated tree blocks in reloc tree with corresponding
2188 static noinline_for_stack
int merge_reloc_root(struct reloc_control
*rc
,
2189 struct btrfs_root
*root
)
2191 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
2192 struct btrfs_key key
;
2193 struct btrfs_key next_key
;
2194 struct btrfs_trans_handle
*trans
= NULL
;
2195 struct btrfs_root
*reloc_root
;
2196 struct btrfs_root_item
*root_item
;
2197 struct btrfs_path
*path
;
2198 struct extent_buffer
*leaf
;
2206 path
= btrfs_alloc_path();
2209 path
->reada
= READA_FORWARD
;
2211 reloc_root
= root
->reloc_root
;
2212 root_item
= &reloc_root
->root_item
;
2214 if (btrfs_disk_key_objectid(&root_item
->drop_progress
) == 0) {
2215 level
= btrfs_root_level(root_item
);
2216 extent_buffer_get(reloc_root
->node
);
2217 path
->nodes
[level
] = reloc_root
->node
;
2218 path
->slots
[level
] = 0;
2220 btrfs_disk_key_to_cpu(&key
, &root_item
->drop_progress
);
2222 level
= root_item
->drop_level
;
2224 path
->lowest_level
= level
;
2225 ret
= btrfs_search_slot(NULL
, reloc_root
, &key
, path
, 0, 0);
2226 path
->lowest_level
= 0;
2228 btrfs_free_path(path
);
2232 btrfs_node_key_to_cpu(path
->nodes
[level
], &next_key
,
2233 path
->slots
[level
]);
2234 WARN_ON(memcmp(&key
, &next_key
, sizeof(key
)));
2236 btrfs_unlock_up_safe(path
, 0);
2239 min_reserved
= fs_info
->nodesize
* (BTRFS_MAX_LEVEL
- 1) * 2;
2240 memset(&next_key
, 0, sizeof(next_key
));
2243 ret
= btrfs_block_rsv_refill(root
, rc
->block_rsv
, min_reserved
,
2244 BTRFS_RESERVE_FLUSH_ALL
);
2249 trans
= btrfs_start_transaction(root
, 0);
2250 if (IS_ERR(trans
)) {
2251 err
= PTR_ERR(trans
);
2255 trans
->block_rsv
= rc
->block_rsv
;
2260 ret
= walk_down_reloc_tree(reloc_root
, path
, &level
);
2268 if (!find_next_key(path
, level
, &key
) &&
2269 btrfs_comp_cpu_keys(&next_key
, &key
) >= 0) {
2272 ret
= replace_path(trans
, rc
, root
, reloc_root
, path
,
2273 &next_key
, level
, max_level
);
2282 btrfs_node_key_to_cpu(path
->nodes
[level
], &key
,
2283 path
->slots
[level
]);
2287 ret
= walk_up_reloc_tree(reloc_root
, path
, &level
);
2293 * save the merging progress in the drop_progress.
2294 * this is OK since root refs == 1 in this case.
2296 btrfs_node_key(path
->nodes
[level
], &root_item
->drop_progress
,
2297 path
->slots
[level
]);
2298 root_item
->drop_level
= level
;
2300 btrfs_end_transaction_throttle(trans
);
2303 btrfs_btree_balance_dirty(fs_info
);
2305 if (replaced
&& rc
->stage
== UPDATE_DATA_PTRS
)
2306 invalidate_extent_cache(root
, &key
, &next_key
);
2310 * handle the case only one block in the fs tree need to be
2311 * relocated and the block is tree root.
2313 leaf
= btrfs_lock_root_node(root
);
2314 ret
= btrfs_cow_block(trans
, root
, leaf
, NULL
, 0, &leaf
);
2315 btrfs_tree_unlock(leaf
);
2316 free_extent_buffer(leaf
);
2320 btrfs_free_path(path
);
2323 insert_dirty_subvol(trans
, rc
, root
);
2326 btrfs_end_transaction_throttle(trans
);
2328 btrfs_btree_balance_dirty(fs_info
);
2330 if (replaced
&& rc
->stage
== UPDATE_DATA_PTRS
)
2331 invalidate_extent_cache(root
, &key
, &next_key
);
2336 static noinline_for_stack
2337 int prepare_to_merge(struct reloc_control
*rc
, int err
)
2339 struct btrfs_root
*root
= rc
->extent_root
;
2340 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
2341 struct btrfs_root
*reloc_root
;
2342 struct btrfs_trans_handle
*trans
;
2343 LIST_HEAD(reloc_roots
);
2347 mutex_lock(&fs_info
->reloc_mutex
);
2348 rc
->merging_rsv_size
+= fs_info
->nodesize
* (BTRFS_MAX_LEVEL
- 1) * 2;
2349 rc
->merging_rsv_size
+= rc
->nodes_relocated
* 2;
2350 mutex_unlock(&fs_info
->reloc_mutex
);
2354 num_bytes
= rc
->merging_rsv_size
;
2355 ret
= btrfs_block_rsv_add(root
, rc
->block_rsv
, num_bytes
,
2356 BTRFS_RESERVE_FLUSH_ALL
);
2361 trans
= btrfs_join_transaction(rc
->extent_root
);
2362 if (IS_ERR(trans
)) {
2364 btrfs_block_rsv_release(fs_info
, rc
->block_rsv
,
2366 return PTR_ERR(trans
);
2370 if (num_bytes
!= rc
->merging_rsv_size
) {
2371 btrfs_end_transaction(trans
);
2372 btrfs_block_rsv_release(fs_info
, rc
->block_rsv
,
2378 rc
->merge_reloc_tree
= 1;
2380 while (!list_empty(&rc
->reloc_roots
)) {
2381 reloc_root
= list_entry(rc
->reloc_roots
.next
,
2382 struct btrfs_root
, root_list
);
2383 list_del_init(&reloc_root
->root_list
);
2385 root
= read_fs_root(fs_info
, reloc_root
->root_key
.offset
);
2386 BUG_ON(IS_ERR(root
));
2387 BUG_ON(root
->reloc_root
!= reloc_root
);
2390 * set reference count to 1, so btrfs_recover_relocation
2391 * knows it should resumes merging
2394 btrfs_set_root_refs(&reloc_root
->root_item
, 1);
2395 btrfs_update_reloc_root(trans
, root
);
2397 list_add(&reloc_root
->root_list
, &reloc_roots
);
2400 list_splice(&reloc_roots
, &rc
->reloc_roots
);
2403 btrfs_commit_transaction(trans
);
2405 btrfs_end_transaction(trans
);
2409 static noinline_for_stack
2410 void free_reloc_roots(struct list_head
*list
)
2412 struct btrfs_root
*reloc_root
;
2414 while (!list_empty(list
)) {
2415 reloc_root
= list_entry(list
->next
, struct btrfs_root
,
2417 __del_reloc_root(reloc_root
);
2418 free_extent_buffer(reloc_root
->node
);
2419 free_extent_buffer(reloc_root
->commit_root
);
2420 reloc_root
->node
= NULL
;
2421 reloc_root
->commit_root
= NULL
;
2425 static noinline_for_stack
2426 void merge_reloc_roots(struct reloc_control
*rc
)
2428 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
2429 struct btrfs_root
*root
;
2430 struct btrfs_root
*reloc_root
;
2431 LIST_HEAD(reloc_roots
);
2435 root
= rc
->extent_root
;
2438 * this serializes us with btrfs_record_root_in_transaction,
2439 * we have to make sure nobody is in the middle of
2440 * adding their roots to the list while we are
2443 mutex_lock(&fs_info
->reloc_mutex
);
2444 list_splice_init(&rc
->reloc_roots
, &reloc_roots
);
2445 mutex_unlock(&fs_info
->reloc_mutex
);
2447 while (!list_empty(&reloc_roots
)) {
2449 reloc_root
= list_entry(reloc_roots
.next
,
2450 struct btrfs_root
, root_list
);
2452 if (btrfs_root_refs(&reloc_root
->root_item
) > 0) {
2453 root
= read_fs_root(fs_info
,
2454 reloc_root
->root_key
.offset
);
2455 BUG_ON(IS_ERR(root
));
2456 BUG_ON(root
->reloc_root
!= reloc_root
);
2458 ret
= merge_reloc_root(rc
, root
);
2460 if (list_empty(&reloc_root
->root_list
))
2461 list_add_tail(&reloc_root
->root_list
,
2466 list_del_init(&reloc_root
->root_list
);
2476 btrfs_handle_fs_error(fs_info
, ret
, NULL
);
2477 if (!list_empty(&reloc_roots
))
2478 free_reloc_roots(&reloc_roots
);
2480 /* new reloc root may be added */
2481 mutex_lock(&fs_info
->reloc_mutex
);
2482 list_splice_init(&rc
->reloc_roots
, &reloc_roots
);
2483 mutex_unlock(&fs_info
->reloc_mutex
);
2484 if (!list_empty(&reloc_roots
))
2485 free_reloc_roots(&reloc_roots
);
2488 BUG_ON(!RB_EMPTY_ROOT(&rc
->reloc_root_tree
.rb_root
));
2491 static void free_block_list(struct rb_root
*blocks
)
2493 struct tree_block
*block
;
2494 struct rb_node
*rb_node
;
2495 while ((rb_node
= rb_first(blocks
))) {
2496 block
= rb_entry(rb_node
, struct tree_block
, rb_node
);
2497 rb_erase(rb_node
, blocks
);
2502 static int record_reloc_root_in_trans(struct btrfs_trans_handle
*trans
,
2503 struct btrfs_root
*reloc_root
)
2505 struct btrfs_fs_info
*fs_info
= reloc_root
->fs_info
;
2506 struct btrfs_root
*root
;
2508 if (reloc_root
->last_trans
== trans
->transid
)
2511 root
= read_fs_root(fs_info
, reloc_root
->root_key
.offset
);
2512 BUG_ON(IS_ERR(root
));
2513 BUG_ON(root
->reloc_root
!= reloc_root
);
2515 return btrfs_record_root_in_trans(trans
, root
);
2518 static noinline_for_stack
2519 struct btrfs_root
*select_reloc_root(struct btrfs_trans_handle
*trans
,
2520 struct reloc_control
*rc
,
2521 struct backref_node
*node
,
2522 struct backref_edge
*edges
[])
2524 struct backref_node
*next
;
2525 struct btrfs_root
*root
;
2531 next
= walk_up_backref(next
, edges
, &index
);
2534 BUG_ON(!test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
));
2536 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
) {
2537 record_reloc_root_in_trans(trans
, root
);
2541 btrfs_record_root_in_trans(trans
, root
);
2542 root
= root
->reloc_root
;
2544 if (next
->new_bytenr
!= root
->node
->start
) {
2545 BUG_ON(next
->new_bytenr
);
2546 BUG_ON(!list_empty(&next
->list
));
2547 next
->new_bytenr
= root
->node
->start
;
2549 list_add_tail(&next
->list
,
2550 &rc
->backref_cache
.changed
);
2551 __mark_block_processed(rc
, next
);
2557 next
= walk_down_backref(edges
, &index
);
2558 if (!next
|| next
->level
<= node
->level
)
2565 /* setup backref node path for btrfs_reloc_cow_block */
2567 rc
->backref_cache
.path
[next
->level
] = next
;
2570 next
= edges
[index
]->node
[UPPER
];
2576 * select a tree root for relocation. return NULL if the block
2577 * is reference counted. we should use do_relocation() in this
2578 * case. return a tree root pointer if the block isn't reference
2579 * counted. return -ENOENT if the block is root of reloc tree.
2581 static noinline_for_stack
2582 struct btrfs_root
*select_one_root(struct backref_node
*node
)
2584 struct backref_node
*next
;
2585 struct btrfs_root
*root
;
2586 struct btrfs_root
*fs_root
= NULL
;
2587 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2593 next
= walk_up_backref(next
, edges
, &index
);
2597 /* no other choice for non-references counted tree */
2598 if (!test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
))
2601 if (root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
)
2607 next
= walk_down_backref(edges
, &index
);
2608 if (!next
|| next
->level
<= node
->level
)
2613 return ERR_PTR(-ENOENT
);
2617 static noinline_for_stack
2618 u64
calcu_metadata_size(struct reloc_control
*rc
,
2619 struct backref_node
*node
, int reserve
)
2621 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
2622 struct backref_node
*next
= node
;
2623 struct backref_edge
*edge
;
2624 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2628 BUG_ON(reserve
&& node
->processed
);
2633 if (next
->processed
&& (reserve
|| next
!= node
))
2636 num_bytes
+= fs_info
->nodesize
;
2638 if (list_empty(&next
->upper
))
2641 edge
= list_entry(next
->upper
.next
,
2642 struct backref_edge
, list
[LOWER
]);
2643 edges
[index
++] = edge
;
2644 next
= edge
->node
[UPPER
];
2646 next
= walk_down_backref(edges
, &index
);
2651 static int reserve_metadata_space(struct btrfs_trans_handle
*trans
,
2652 struct reloc_control
*rc
,
2653 struct backref_node
*node
)
2655 struct btrfs_root
*root
= rc
->extent_root
;
2656 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
2661 num_bytes
= calcu_metadata_size(rc
, node
, 1) * 2;
2663 trans
->block_rsv
= rc
->block_rsv
;
2664 rc
->reserved_bytes
+= num_bytes
;
2667 * We are under a transaction here so we can only do limited flushing.
2668 * If we get an enospc just kick back -EAGAIN so we know to drop the
2669 * transaction and try to refill when we can flush all the things.
2671 ret
= btrfs_block_rsv_refill(root
, rc
->block_rsv
, num_bytes
,
2672 BTRFS_RESERVE_FLUSH_LIMIT
);
2674 tmp
= fs_info
->nodesize
* RELOCATION_RESERVED_NODES
;
2675 while (tmp
<= rc
->reserved_bytes
)
2678 * only one thread can access block_rsv at this point,
2679 * so we don't need hold lock to protect block_rsv.
2680 * we expand more reservation size here to allow enough
2681 * space for relocation and we will return earlier in
2684 rc
->block_rsv
->size
= tmp
+ fs_info
->nodesize
*
2685 RELOCATION_RESERVED_NODES
;
2693 * relocate a block tree, and then update pointers in upper level
2694 * blocks that reference the block to point to the new location.
2696 * if called by link_to_upper, the block has already been relocated.
2697 * in that case this function just updates pointers.
2699 static int do_relocation(struct btrfs_trans_handle
*trans
,
2700 struct reloc_control
*rc
,
2701 struct backref_node
*node
,
2702 struct btrfs_key
*key
,
2703 struct btrfs_path
*path
, int lowest
)
2705 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
2706 struct backref_node
*upper
;
2707 struct backref_edge
*edge
;
2708 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2709 struct btrfs_root
*root
;
2710 struct extent_buffer
*eb
;
2718 BUG_ON(lowest
&& node
->eb
);
2720 path
->lowest_level
= node
->level
+ 1;
2721 rc
->backref_cache
.path
[node
->level
] = node
;
2722 list_for_each_entry(edge
, &node
->upper
, list
[LOWER
]) {
2723 struct btrfs_key first_key
;
2727 upper
= edge
->node
[UPPER
];
2728 root
= select_reloc_root(trans
, rc
, upper
, edges
);
2731 if (upper
->eb
&& !upper
->locked
) {
2733 ret
= btrfs_bin_search(upper
->eb
, key
,
2734 upper
->level
, &slot
);
2740 bytenr
= btrfs_node_blockptr(upper
->eb
, slot
);
2741 if (node
->eb
->start
== bytenr
)
2744 drop_node_buffer(upper
);
2748 ret
= btrfs_search_slot(trans
, root
, key
, path
, 0, 1);
2755 btrfs_release_path(path
);
2760 upper
->eb
= path
->nodes
[upper
->level
];
2761 path
->nodes
[upper
->level
] = NULL
;
2763 BUG_ON(upper
->eb
!= path
->nodes
[upper
->level
]);
2767 path
->locks
[upper
->level
] = 0;
2769 slot
= path
->slots
[upper
->level
];
2770 btrfs_release_path(path
);
2772 ret
= btrfs_bin_search(upper
->eb
, key
, upper
->level
,
2781 bytenr
= btrfs_node_blockptr(upper
->eb
, slot
);
2783 if (bytenr
!= node
->bytenr
) {
2784 btrfs_err(root
->fs_info
,
2785 "lowest leaf/node mismatch: bytenr %llu node->bytenr %llu slot %d upper %llu",
2786 bytenr
, node
->bytenr
, slot
,
2792 if (node
->eb
->start
== bytenr
)
2796 blocksize
= root
->fs_info
->nodesize
;
2797 generation
= btrfs_node_ptr_generation(upper
->eb
, slot
);
2798 btrfs_node_key_to_cpu(upper
->eb
, &first_key
, slot
);
2799 eb
= read_tree_block(fs_info
, bytenr
, generation
,
2800 upper
->level
- 1, &first_key
);
2804 } else if (!extent_buffer_uptodate(eb
)) {
2805 free_extent_buffer(eb
);
2809 btrfs_tree_lock(eb
);
2810 btrfs_set_lock_blocking_write(eb
);
2813 ret
= btrfs_cow_block(trans
, root
, eb
, upper
->eb
,
2815 btrfs_tree_unlock(eb
);
2816 free_extent_buffer(eb
);
2821 BUG_ON(node
->eb
!= eb
);
2823 btrfs_set_node_blockptr(upper
->eb
, slot
,
2825 btrfs_set_node_ptr_generation(upper
->eb
, slot
,
2827 btrfs_mark_buffer_dirty(upper
->eb
);
2829 ret
= btrfs_inc_extent_ref(trans
, root
,
2830 node
->eb
->start
, blocksize
,
2832 btrfs_header_owner(upper
->eb
),
2836 ret
= btrfs_drop_subtree(trans
, root
, eb
, upper
->eb
);
2840 if (!upper
->pending
)
2841 drop_node_buffer(upper
);
2843 unlock_node_buffer(upper
);
2848 if (!err
&& node
->pending
) {
2849 drop_node_buffer(node
);
2850 list_move_tail(&node
->list
, &rc
->backref_cache
.changed
);
2854 path
->lowest_level
= 0;
2855 BUG_ON(err
== -ENOSPC
);
2859 static int link_to_upper(struct btrfs_trans_handle
*trans
,
2860 struct reloc_control
*rc
,
2861 struct backref_node
*node
,
2862 struct btrfs_path
*path
)
2864 struct btrfs_key key
;
2866 btrfs_node_key_to_cpu(node
->eb
, &key
, 0);
2867 return do_relocation(trans
, rc
, node
, &key
, path
, 0);
2870 static int finish_pending_nodes(struct btrfs_trans_handle
*trans
,
2871 struct reloc_control
*rc
,
2872 struct btrfs_path
*path
, int err
)
2875 struct backref_cache
*cache
= &rc
->backref_cache
;
2876 struct backref_node
*node
;
2880 for (level
= 0; level
< BTRFS_MAX_LEVEL
; level
++) {
2881 while (!list_empty(&cache
->pending
[level
])) {
2882 node
= list_entry(cache
->pending
[level
].next
,
2883 struct backref_node
, list
);
2884 list_move_tail(&node
->list
, &list
);
2885 BUG_ON(!node
->pending
);
2888 ret
= link_to_upper(trans
, rc
, node
, path
);
2893 list_splice_init(&list
, &cache
->pending
[level
]);
2898 static void mark_block_processed(struct reloc_control
*rc
,
2899 u64 bytenr
, u32 blocksize
)
2901 set_extent_bits(&rc
->processed_blocks
, bytenr
, bytenr
+ blocksize
- 1,
2905 static void __mark_block_processed(struct reloc_control
*rc
,
2906 struct backref_node
*node
)
2909 if (node
->level
== 0 ||
2910 in_block_group(node
->bytenr
, rc
->block_group
)) {
2911 blocksize
= rc
->extent_root
->fs_info
->nodesize
;
2912 mark_block_processed(rc
, node
->bytenr
, blocksize
);
2914 node
->processed
= 1;
2918 * mark a block and all blocks directly/indirectly reference the block
2921 static void update_processed_blocks(struct reloc_control
*rc
,
2922 struct backref_node
*node
)
2924 struct backref_node
*next
= node
;
2925 struct backref_edge
*edge
;
2926 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2932 if (next
->processed
)
2935 __mark_block_processed(rc
, next
);
2937 if (list_empty(&next
->upper
))
2940 edge
= list_entry(next
->upper
.next
,
2941 struct backref_edge
, list
[LOWER
]);
2942 edges
[index
++] = edge
;
2943 next
= edge
->node
[UPPER
];
2945 next
= walk_down_backref(edges
, &index
);
2949 static int tree_block_processed(u64 bytenr
, struct reloc_control
*rc
)
2951 u32 blocksize
= rc
->extent_root
->fs_info
->nodesize
;
2953 if (test_range_bit(&rc
->processed_blocks
, bytenr
,
2954 bytenr
+ blocksize
- 1, EXTENT_DIRTY
, 1, NULL
))
2959 static int get_tree_block_key(struct btrfs_fs_info
*fs_info
,
2960 struct tree_block
*block
)
2962 struct extent_buffer
*eb
;
2964 BUG_ON(block
->key_ready
);
2965 eb
= read_tree_block(fs_info
, block
->bytenr
, block
->key
.offset
,
2966 block
->level
, NULL
);
2969 } else if (!extent_buffer_uptodate(eb
)) {
2970 free_extent_buffer(eb
);
2973 if (block
->level
== 0)
2974 btrfs_item_key_to_cpu(eb
, &block
->key
, 0);
2976 btrfs_node_key_to_cpu(eb
, &block
->key
, 0);
2977 free_extent_buffer(eb
);
2978 block
->key_ready
= 1;
2983 * helper function to relocate a tree block
2985 static int relocate_tree_block(struct btrfs_trans_handle
*trans
,
2986 struct reloc_control
*rc
,
2987 struct backref_node
*node
,
2988 struct btrfs_key
*key
,
2989 struct btrfs_path
*path
)
2991 struct btrfs_root
*root
;
2997 BUG_ON(node
->processed
);
2998 root
= select_one_root(node
);
2999 if (root
== ERR_PTR(-ENOENT
)) {
3000 update_processed_blocks(rc
, node
);
3004 if (!root
|| test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
)) {
3005 ret
= reserve_metadata_space(trans
, rc
, node
);
3011 if (test_bit(BTRFS_ROOT_REF_COWS
, &root
->state
)) {
3012 BUG_ON(node
->new_bytenr
);
3013 BUG_ON(!list_empty(&node
->list
));
3014 btrfs_record_root_in_trans(trans
, root
);
3015 root
= root
->reloc_root
;
3016 node
->new_bytenr
= root
->node
->start
;
3018 list_add_tail(&node
->list
, &rc
->backref_cache
.changed
);
3020 path
->lowest_level
= node
->level
;
3021 ret
= btrfs_search_slot(trans
, root
, key
, path
, 0, 1);
3022 btrfs_release_path(path
);
3027 update_processed_blocks(rc
, node
);
3029 ret
= do_relocation(trans
, rc
, node
, key
, path
, 1);
3032 if (ret
|| node
->level
== 0 || node
->cowonly
)
3033 remove_backref_node(&rc
->backref_cache
, node
);
3038 * relocate a list of blocks
3040 static noinline_for_stack
3041 int relocate_tree_blocks(struct btrfs_trans_handle
*trans
,
3042 struct reloc_control
*rc
, struct rb_root
*blocks
)
3044 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3045 struct backref_node
*node
;
3046 struct btrfs_path
*path
;
3047 struct tree_block
*block
;
3048 struct tree_block
*next
;
3052 path
= btrfs_alloc_path();
3055 goto out_free_blocks
;
3058 /* Kick in readahead for tree blocks with missing keys */
3059 rbtree_postorder_for_each_entry_safe(block
, next
, blocks
, rb_node
) {
3060 if (!block
->key_ready
)
3061 readahead_tree_block(fs_info
, block
->bytenr
);
3064 /* Get first keys */
3065 rbtree_postorder_for_each_entry_safe(block
, next
, blocks
, rb_node
) {
3066 if (!block
->key_ready
) {
3067 err
= get_tree_block_key(fs_info
, block
);
3073 /* Do tree relocation */
3074 rbtree_postorder_for_each_entry_safe(block
, next
, blocks
, rb_node
) {
3075 node
= build_backref_tree(rc
, &block
->key
,
3076 block
->level
, block
->bytenr
);
3078 err
= PTR_ERR(node
);
3082 ret
= relocate_tree_block(trans
, rc
, node
, &block
->key
,
3085 if (ret
!= -EAGAIN
|| &block
->rb_node
== rb_first(blocks
))
3091 err
= finish_pending_nodes(trans
, rc
, path
, err
);
3094 btrfs_free_path(path
);
3096 free_block_list(blocks
);
3100 static noinline_for_stack
3101 int prealloc_file_extent_cluster(struct inode
*inode
,
3102 struct file_extent_cluster
*cluster
)
3107 u64 offset
= BTRFS_I(inode
)->index_cnt
;
3111 u64 prealloc_start
= cluster
->start
- offset
;
3112 u64 prealloc_end
= cluster
->end
- offset
;
3114 struct extent_changeset
*data_reserved
= NULL
;
3116 BUG_ON(cluster
->start
!= cluster
->boundary
[0]);
3119 ret
= btrfs_check_data_free_space(inode
, &data_reserved
, prealloc_start
,
3120 prealloc_end
+ 1 - prealloc_start
);
3124 cur_offset
= prealloc_start
;
3125 while (nr
< cluster
->nr
) {
3126 start
= cluster
->boundary
[nr
] - offset
;
3127 if (nr
+ 1 < cluster
->nr
)
3128 end
= cluster
->boundary
[nr
+ 1] - 1 - offset
;
3130 end
= cluster
->end
- offset
;
3132 lock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
3133 num_bytes
= end
+ 1 - start
;
3134 if (cur_offset
< start
)
3135 btrfs_free_reserved_data_space(inode
, data_reserved
,
3136 cur_offset
, start
- cur_offset
);
3137 ret
= btrfs_prealloc_file_range(inode
, 0, start
,
3138 num_bytes
, num_bytes
,
3139 end
+ 1, &alloc_hint
);
3140 cur_offset
= end
+ 1;
3141 unlock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
3146 if (cur_offset
< prealloc_end
)
3147 btrfs_free_reserved_data_space(inode
, data_reserved
,
3148 cur_offset
, prealloc_end
+ 1 - cur_offset
);
3150 inode_unlock(inode
);
3151 extent_changeset_free(data_reserved
);
3155 static noinline_for_stack
3156 int setup_extent_mapping(struct inode
*inode
, u64 start
, u64 end
,
3159 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
3160 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
3161 struct extent_map
*em
;
3164 em
= alloc_extent_map();
3169 em
->len
= end
+ 1 - start
;
3170 em
->block_len
= em
->len
;
3171 em
->block_start
= block_start
;
3172 em
->bdev
= fs_info
->fs_devices
->latest_bdev
;
3173 set_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
3175 lock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
3177 write_lock(&em_tree
->lock
);
3178 ret
= add_extent_mapping(em_tree
, em
, 0);
3179 write_unlock(&em_tree
->lock
);
3180 if (ret
!= -EEXIST
) {
3181 free_extent_map(em
);
3184 btrfs_drop_extent_cache(BTRFS_I(inode
), start
, end
, 0);
3186 unlock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
3190 static int relocate_file_extent_cluster(struct inode
*inode
,
3191 struct file_extent_cluster
*cluster
)
3193 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
3196 u64 offset
= BTRFS_I(inode
)->index_cnt
;
3197 unsigned long index
;
3198 unsigned long last_index
;
3200 struct file_ra_state
*ra
;
3201 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
3208 ra
= kzalloc(sizeof(*ra
), GFP_NOFS
);
3212 ret
= prealloc_file_extent_cluster(inode
, cluster
);
3216 file_ra_state_init(ra
, inode
->i_mapping
);
3218 ret
= setup_extent_mapping(inode
, cluster
->start
- offset
,
3219 cluster
->end
- offset
, cluster
->start
);
3223 index
= (cluster
->start
- offset
) >> PAGE_SHIFT
;
3224 last_index
= (cluster
->end
- offset
) >> PAGE_SHIFT
;
3225 while (index
<= last_index
) {
3226 ret
= btrfs_delalloc_reserve_metadata(BTRFS_I(inode
),
3231 page
= find_lock_page(inode
->i_mapping
, index
);
3233 page_cache_sync_readahead(inode
->i_mapping
,
3235 last_index
+ 1 - index
);
3236 page
= find_or_create_page(inode
->i_mapping
, index
,
3239 btrfs_delalloc_release_metadata(BTRFS_I(inode
),
3246 if (PageReadahead(page
)) {
3247 page_cache_async_readahead(inode
->i_mapping
,
3248 ra
, NULL
, page
, index
,
3249 last_index
+ 1 - index
);
3252 if (!PageUptodate(page
)) {
3253 btrfs_readpage(NULL
, page
);
3255 if (!PageUptodate(page
)) {
3258 btrfs_delalloc_release_metadata(BTRFS_I(inode
),
3260 btrfs_delalloc_release_extents(BTRFS_I(inode
),
3267 page_start
= page_offset(page
);
3268 page_end
= page_start
+ PAGE_SIZE
- 1;
3270 lock_extent(&BTRFS_I(inode
)->io_tree
, page_start
, page_end
);
3272 set_page_extent_mapped(page
);
3274 if (nr
< cluster
->nr
&&
3275 page_start
+ offset
== cluster
->boundary
[nr
]) {
3276 set_extent_bits(&BTRFS_I(inode
)->io_tree
,
3277 page_start
, page_end
,
3282 ret
= btrfs_set_extent_delalloc(inode
, page_start
, page_end
, 0,
3287 btrfs_delalloc_release_metadata(BTRFS_I(inode
),
3289 btrfs_delalloc_release_extents(BTRFS_I(inode
),
3292 clear_extent_bits(&BTRFS_I(inode
)->io_tree
,
3293 page_start
, page_end
,
3294 EXTENT_LOCKED
| EXTENT_BOUNDARY
);
3298 set_page_dirty(page
);
3300 unlock_extent(&BTRFS_I(inode
)->io_tree
,
3301 page_start
, page_end
);
3306 btrfs_delalloc_release_extents(BTRFS_I(inode
), PAGE_SIZE
,
3308 balance_dirty_pages_ratelimited(inode
->i_mapping
);
3309 btrfs_throttle(fs_info
);
3311 WARN_ON(nr
!= cluster
->nr
);
3317 static noinline_for_stack
3318 int relocate_data_extent(struct inode
*inode
, struct btrfs_key
*extent_key
,
3319 struct file_extent_cluster
*cluster
)
3323 if (cluster
->nr
> 0 && extent_key
->objectid
!= cluster
->end
+ 1) {
3324 ret
= relocate_file_extent_cluster(inode
, cluster
);
3331 cluster
->start
= extent_key
->objectid
;
3333 BUG_ON(cluster
->nr
>= MAX_EXTENTS
);
3334 cluster
->end
= extent_key
->objectid
+ extent_key
->offset
- 1;
3335 cluster
->boundary
[cluster
->nr
] = extent_key
->objectid
;
3338 if (cluster
->nr
>= MAX_EXTENTS
) {
3339 ret
= relocate_file_extent_cluster(inode
, cluster
);
3348 * helper to add a tree block to the list.
3349 * the major work is getting the generation and level of the block
3351 static int add_tree_block(struct reloc_control
*rc
,
3352 struct btrfs_key
*extent_key
,
3353 struct btrfs_path
*path
,
3354 struct rb_root
*blocks
)
3356 struct extent_buffer
*eb
;
3357 struct btrfs_extent_item
*ei
;
3358 struct btrfs_tree_block_info
*bi
;
3359 struct tree_block
*block
;
3360 struct rb_node
*rb_node
;
3365 eb
= path
->nodes
[0];
3366 item_size
= btrfs_item_size_nr(eb
, path
->slots
[0]);
3368 if (extent_key
->type
== BTRFS_METADATA_ITEM_KEY
||
3369 item_size
>= sizeof(*ei
) + sizeof(*bi
)) {
3370 ei
= btrfs_item_ptr(eb
, path
->slots
[0],
3371 struct btrfs_extent_item
);
3372 if (extent_key
->type
== BTRFS_EXTENT_ITEM_KEY
) {
3373 bi
= (struct btrfs_tree_block_info
*)(ei
+ 1);
3374 level
= btrfs_tree_block_level(eb
, bi
);
3376 level
= (int)extent_key
->offset
;
3378 generation
= btrfs_extent_generation(eb
, ei
);
3379 } else if (unlikely(item_size
== sizeof(struct btrfs_extent_item_v0
))) {
3380 btrfs_print_v0_err(eb
->fs_info
);
3381 btrfs_handle_fs_error(eb
->fs_info
, -EINVAL
, NULL
);
3387 btrfs_release_path(path
);
3389 BUG_ON(level
== -1);
3391 block
= kmalloc(sizeof(*block
), GFP_NOFS
);
3395 block
->bytenr
= extent_key
->objectid
;
3396 block
->key
.objectid
= rc
->extent_root
->fs_info
->nodesize
;
3397 block
->key
.offset
= generation
;
3398 block
->level
= level
;
3399 block
->key_ready
= 0;
3401 rb_node
= tree_insert(blocks
, block
->bytenr
, &block
->rb_node
);
3403 backref_tree_panic(rb_node
, -EEXIST
, block
->bytenr
);
3409 * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY
3411 static int __add_tree_block(struct reloc_control
*rc
,
3412 u64 bytenr
, u32 blocksize
,
3413 struct rb_root
*blocks
)
3415 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3416 struct btrfs_path
*path
;
3417 struct btrfs_key key
;
3419 bool skinny
= btrfs_fs_incompat(fs_info
, SKINNY_METADATA
);
3421 if (tree_block_processed(bytenr
, rc
))
3424 if (tree_search(blocks
, bytenr
))
3427 path
= btrfs_alloc_path();
3431 key
.objectid
= bytenr
;
3433 key
.type
= BTRFS_METADATA_ITEM_KEY
;
3434 key
.offset
= (u64
)-1;
3436 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
3437 key
.offset
= blocksize
;
3440 path
->search_commit_root
= 1;
3441 path
->skip_locking
= 1;
3442 ret
= btrfs_search_slot(NULL
, rc
->extent_root
, &key
, path
, 0, 0);
3446 if (ret
> 0 && skinny
) {
3447 if (path
->slots
[0]) {
3449 btrfs_item_key_to_cpu(path
->nodes
[0], &key
,
3451 if (key
.objectid
== bytenr
&&
3452 (key
.type
== BTRFS_METADATA_ITEM_KEY
||
3453 (key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
3454 key
.offset
== blocksize
)))
3460 btrfs_release_path(path
);
3466 btrfs_print_leaf(path
->nodes
[0]);
3468 "tree block extent item (%llu) is not found in extent tree",
3475 ret
= add_tree_block(rc
, &key
, path
, blocks
);
3477 btrfs_free_path(path
);
3482 * helper to check if the block use full backrefs for pointers in it
3484 static int block_use_full_backref(struct reloc_control
*rc
,
3485 struct extent_buffer
*eb
)
3490 if (btrfs_header_flag(eb
, BTRFS_HEADER_FLAG_RELOC
) ||
3491 btrfs_header_backref_rev(eb
) < BTRFS_MIXED_BACKREF_REV
)
3494 ret
= btrfs_lookup_extent_info(NULL
, rc
->extent_root
->fs_info
,
3495 eb
->start
, btrfs_header_level(eb
), 1,
3499 if (flags
& BTRFS_BLOCK_FLAG_FULL_BACKREF
)
3506 static int delete_block_group_cache(struct btrfs_fs_info
*fs_info
,
3507 struct btrfs_block_group_cache
*block_group
,
3508 struct inode
*inode
,
3511 struct btrfs_key key
;
3512 struct btrfs_root
*root
= fs_info
->tree_root
;
3513 struct btrfs_trans_handle
*trans
;
3520 key
.type
= BTRFS_INODE_ITEM_KEY
;
3523 inode
= btrfs_iget(fs_info
->sb
, &key
, root
, NULL
);
3528 ret
= btrfs_check_trunc_cache_free_space(fs_info
,
3529 &fs_info
->global_block_rsv
);
3533 trans
= btrfs_join_transaction(root
);
3534 if (IS_ERR(trans
)) {
3535 ret
= PTR_ERR(trans
);
3539 ret
= btrfs_truncate_free_space_cache(trans
, block_group
, inode
);
3541 btrfs_end_transaction(trans
);
3542 btrfs_btree_balance_dirty(fs_info
);
3549 * helper to add tree blocks for backref of type BTRFS_EXTENT_DATA_REF_KEY
3550 * this function scans fs tree to find blocks reference the data extent
3552 static int find_data_references(struct reloc_control
*rc
,
3553 struct btrfs_key
*extent_key
,
3554 struct extent_buffer
*leaf
,
3555 struct btrfs_extent_data_ref
*ref
,
3556 struct rb_root
*blocks
)
3558 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3559 struct btrfs_path
*path
;
3560 struct tree_block
*block
;
3561 struct btrfs_root
*root
;
3562 struct btrfs_file_extent_item
*fi
;
3563 struct rb_node
*rb_node
;
3564 struct btrfs_key key
;
3575 ref_root
= btrfs_extent_data_ref_root(leaf
, ref
);
3576 ref_objectid
= btrfs_extent_data_ref_objectid(leaf
, ref
);
3577 ref_offset
= btrfs_extent_data_ref_offset(leaf
, ref
);
3578 ref_count
= btrfs_extent_data_ref_count(leaf
, ref
);
3581 * This is an extent belonging to the free space cache, lets just delete
3582 * it and redo the search.
3584 if (ref_root
== BTRFS_ROOT_TREE_OBJECTID
) {
3585 ret
= delete_block_group_cache(fs_info
, rc
->block_group
,
3586 NULL
, ref_objectid
);
3592 path
= btrfs_alloc_path();
3595 path
->reada
= READA_FORWARD
;
3597 root
= read_fs_root(fs_info
, ref_root
);
3599 err
= PTR_ERR(root
);
3603 key
.objectid
= ref_objectid
;
3604 key
.type
= BTRFS_EXTENT_DATA_KEY
;
3605 if (ref_offset
> ((u64
)-1 << 32))
3608 key
.offset
= ref_offset
;
3610 path
->search_commit_root
= 1;
3611 path
->skip_locking
= 1;
3612 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
3618 leaf
= path
->nodes
[0];
3619 nritems
= btrfs_header_nritems(leaf
);
3621 * the references in tree blocks that use full backrefs
3622 * are not counted in
3624 if (block_use_full_backref(rc
, leaf
))
3628 rb_node
= tree_search(blocks
, leaf
->start
);
3633 path
->slots
[0] = nritems
;
3636 while (ref_count
> 0) {
3637 while (path
->slots
[0] >= nritems
) {
3638 ret
= btrfs_next_leaf(root
, path
);
3643 if (WARN_ON(ret
> 0))
3646 leaf
= path
->nodes
[0];
3647 nritems
= btrfs_header_nritems(leaf
);
3650 if (block_use_full_backref(rc
, leaf
))
3654 rb_node
= tree_search(blocks
, leaf
->start
);
3659 path
->slots
[0] = nritems
;
3663 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
3664 if (WARN_ON(key
.objectid
!= ref_objectid
||
3665 key
.type
!= BTRFS_EXTENT_DATA_KEY
))
3668 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
3669 struct btrfs_file_extent_item
);
3671 if (btrfs_file_extent_type(leaf
, fi
) ==
3672 BTRFS_FILE_EXTENT_INLINE
)
3675 if (btrfs_file_extent_disk_bytenr(leaf
, fi
) !=
3676 extent_key
->objectid
)
3679 key
.offset
-= btrfs_file_extent_offset(leaf
, fi
);
3680 if (key
.offset
!= ref_offset
)
3688 if (!tree_block_processed(leaf
->start
, rc
)) {
3689 block
= kmalloc(sizeof(*block
), GFP_NOFS
);
3694 block
->bytenr
= leaf
->start
;
3695 btrfs_item_key_to_cpu(leaf
, &block
->key
, 0);
3697 block
->key_ready
= 1;
3698 rb_node
= tree_insert(blocks
, block
->bytenr
,
3701 backref_tree_panic(rb_node
, -EEXIST
,
3707 path
->slots
[0] = nritems
;
3713 btrfs_free_path(path
);
3718 * helper to find all tree blocks that reference a given data extent
3720 static noinline_for_stack
3721 int add_data_references(struct reloc_control
*rc
,
3722 struct btrfs_key
*extent_key
,
3723 struct btrfs_path
*path
,
3724 struct rb_root
*blocks
)
3726 struct btrfs_key key
;
3727 struct extent_buffer
*eb
;
3728 struct btrfs_extent_data_ref
*dref
;
3729 struct btrfs_extent_inline_ref
*iref
;
3732 u32 blocksize
= rc
->extent_root
->fs_info
->nodesize
;
3736 eb
= path
->nodes
[0];
3737 ptr
= btrfs_item_ptr_offset(eb
, path
->slots
[0]);
3738 end
= ptr
+ btrfs_item_size_nr(eb
, path
->slots
[0]);
3739 ptr
+= sizeof(struct btrfs_extent_item
);
3742 iref
= (struct btrfs_extent_inline_ref
*)ptr
;
3743 key
.type
= btrfs_get_extent_inline_ref_type(eb
, iref
,
3744 BTRFS_REF_TYPE_DATA
);
3745 if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
) {
3746 key
.offset
= btrfs_extent_inline_ref_offset(eb
, iref
);
3747 ret
= __add_tree_block(rc
, key
.offset
, blocksize
,
3749 } else if (key
.type
== BTRFS_EXTENT_DATA_REF_KEY
) {
3750 dref
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
3751 ret
= find_data_references(rc
, extent_key
,
3755 btrfs_err(rc
->extent_root
->fs_info
,
3756 "extent %llu slot %d has an invalid inline ref type",
3757 eb
->start
, path
->slots
[0]);
3763 ptr
+= btrfs_extent_inline_ref_size(key
.type
);
3769 eb
= path
->nodes
[0];
3770 if (path
->slots
[0] >= btrfs_header_nritems(eb
)) {
3771 ret
= btrfs_next_leaf(rc
->extent_root
, path
);
3778 eb
= path
->nodes
[0];
3781 btrfs_item_key_to_cpu(eb
, &key
, path
->slots
[0]);
3782 if (key
.objectid
!= extent_key
->objectid
)
3785 if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
) {
3786 ret
= __add_tree_block(rc
, key
.offset
, blocksize
,
3788 } else if (key
.type
== BTRFS_EXTENT_DATA_REF_KEY
) {
3789 dref
= btrfs_item_ptr(eb
, path
->slots
[0],
3790 struct btrfs_extent_data_ref
);
3791 ret
= find_data_references(rc
, extent_key
,
3793 } else if (unlikely(key
.type
== BTRFS_EXTENT_REF_V0_KEY
)) {
3794 btrfs_print_v0_err(eb
->fs_info
);
3795 btrfs_handle_fs_error(eb
->fs_info
, -EINVAL
, NULL
);
3807 btrfs_release_path(path
);
3809 free_block_list(blocks
);
3814 * helper to find next unprocessed extent
3816 static noinline_for_stack
3817 int find_next_extent(struct reloc_control
*rc
, struct btrfs_path
*path
,
3818 struct btrfs_key
*extent_key
)
3820 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3821 struct btrfs_key key
;
3822 struct extent_buffer
*leaf
;
3823 u64 start
, end
, last
;
3826 last
= rc
->block_group
->key
.objectid
+ rc
->block_group
->key
.offset
;
3829 if (rc
->search_start
>= last
) {
3834 key
.objectid
= rc
->search_start
;
3835 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
3838 path
->search_commit_root
= 1;
3839 path
->skip_locking
= 1;
3840 ret
= btrfs_search_slot(NULL
, rc
->extent_root
, &key
, path
,
3845 leaf
= path
->nodes
[0];
3846 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
3847 ret
= btrfs_next_leaf(rc
->extent_root
, path
);
3850 leaf
= path
->nodes
[0];
3853 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
3854 if (key
.objectid
>= last
) {
3859 if (key
.type
!= BTRFS_EXTENT_ITEM_KEY
&&
3860 key
.type
!= BTRFS_METADATA_ITEM_KEY
) {
3865 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
3866 key
.objectid
+ key
.offset
<= rc
->search_start
) {
3871 if (key
.type
== BTRFS_METADATA_ITEM_KEY
&&
3872 key
.objectid
+ fs_info
->nodesize
<=
3878 ret
= find_first_extent_bit(&rc
->processed_blocks
,
3879 key
.objectid
, &start
, &end
,
3880 EXTENT_DIRTY
, NULL
);
3882 if (ret
== 0 && start
<= key
.objectid
) {
3883 btrfs_release_path(path
);
3884 rc
->search_start
= end
+ 1;
3886 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
)
3887 rc
->search_start
= key
.objectid
+ key
.offset
;
3889 rc
->search_start
= key
.objectid
+
3891 memcpy(extent_key
, &key
, sizeof(key
));
3895 btrfs_release_path(path
);
3899 static void set_reloc_control(struct reloc_control
*rc
)
3901 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3903 mutex_lock(&fs_info
->reloc_mutex
);
3904 fs_info
->reloc_ctl
= rc
;
3905 mutex_unlock(&fs_info
->reloc_mutex
);
3908 static void unset_reloc_control(struct reloc_control
*rc
)
3910 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3912 mutex_lock(&fs_info
->reloc_mutex
);
3913 fs_info
->reloc_ctl
= NULL
;
3914 mutex_unlock(&fs_info
->reloc_mutex
);
3917 static int check_extent_flags(u64 flags
)
3919 if ((flags
& BTRFS_EXTENT_FLAG_DATA
) &&
3920 (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
))
3922 if (!(flags
& BTRFS_EXTENT_FLAG_DATA
) &&
3923 !(flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
))
3925 if ((flags
& BTRFS_EXTENT_FLAG_DATA
) &&
3926 (flags
& BTRFS_BLOCK_FLAG_FULL_BACKREF
))
3931 static noinline_for_stack
3932 int prepare_to_relocate(struct reloc_control
*rc
)
3934 struct btrfs_trans_handle
*trans
;
3937 rc
->block_rsv
= btrfs_alloc_block_rsv(rc
->extent_root
->fs_info
,
3938 BTRFS_BLOCK_RSV_TEMP
);
3942 memset(&rc
->cluster
, 0, sizeof(rc
->cluster
));
3943 rc
->search_start
= rc
->block_group
->key
.objectid
;
3944 rc
->extents_found
= 0;
3945 rc
->nodes_relocated
= 0;
3946 rc
->merging_rsv_size
= 0;
3947 rc
->reserved_bytes
= 0;
3948 rc
->block_rsv
->size
= rc
->extent_root
->fs_info
->nodesize
*
3949 RELOCATION_RESERVED_NODES
;
3950 ret
= btrfs_block_rsv_refill(rc
->extent_root
,
3951 rc
->block_rsv
, rc
->block_rsv
->size
,
3952 BTRFS_RESERVE_FLUSH_ALL
);
3956 rc
->create_reloc_tree
= 1;
3957 set_reloc_control(rc
);
3959 trans
= btrfs_join_transaction(rc
->extent_root
);
3960 if (IS_ERR(trans
)) {
3961 unset_reloc_control(rc
);
3963 * extent tree is not a ref_cow tree and has no reloc_root to
3964 * cleanup. And callers are responsible to free the above
3967 return PTR_ERR(trans
);
3969 btrfs_commit_transaction(trans
);
3973 static noinline_for_stack
int relocate_block_group(struct reloc_control
*rc
)
3975 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3976 struct rb_root blocks
= RB_ROOT
;
3977 struct btrfs_key key
;
3978 struct btrfs_trans_handle
*trans
= NULL
;
3979 struct btrfs_path
*path
;
3980 struct btrfs_extent_item
*ei
;
3987 path
= btrfs_alloc_path();
3990 path
->reada
= READA_FORWARD
;
3992 ret
= prepare_to_relocate(rc
);
3999 rc
->reserved_bytes
= 0;
4000 ret
= btrfs_block_rsv_refill(rc
->extent_root
,
4001 rc
->block_rsv
, rc
->block_rsv
->size
,
4002 BTRFS_RESERVE_FLUSH_ALL
);
4008 trans
= btrfs_start_transaction(rc
->extent_root
, 0);
4009 if (IS_ERR(trans
)) {
4010 err
= PTR_ERR(trans
);
4015 if (update_backref_cache(trans
, &rc
->backref_cache
)) {
4016 btrfs_end_transaction(trans
);
4021 ret
= find_next_extent(rc
, path
, &key
);
4027 rc
->extents_found
++;
4029 ei
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
4030 struct btrfs_extent_item
);
4031 item_size
= btrfs_item_size_nr(path
->nodes
[0], path
->slots
[0]);
4032 if (item_size
>= sizeof(*ei
)) {
4033 flags
= btrfs_extent_flags(path
->nodes
[0], ei
);
4034 ret
= check_extent_flags(flags
);
4036 } else if (unlikely(item_size
== sizeof(struct btrfs_extent_item_v0
))) {
4038 btrfs_print_v0_err(trans
->fs_info
);
4039 btrfs_abort_transaction(trans
, err
);
4045 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
) {
4046 ret
= add_tree_block(rc
, &key
, path
, &blocks
);
4047 } else if (rc
->stage
== UPDATE_DATA_PTRS
&&
4048 (flags
& BTRFS_EXTENT_FLAG_DATA
)) {
4049 ret
= add_data_references(rc
, &key
, path
, &blocks
);
4051 btrfs_release_path(path
);
4059 if (!RB_EMPTY_ROOT(&blocks
)) {
4060 ret
= relocate_tree_blocks(trans
, rc
, &blocks
);
4063 * if we fail to relocate tree blocks, force to update
4064 * backref cache when committing transaction.
4066 rc
->backref_cache
.last_trans
= trans
->transid
- 1;
4068 if (ret
!= -EAGAIN
) {
4072 rc
->extents_found
--;
4073 rc
->search_start
= key
.objectid
;
4077 btrfs_end_transaction_throttle(trans
);
4078 btrfs_btree_balance_dirty(fs_info
);
4081 if (rc
->stage
== MOVE_DATA_EXTENTS
&&
4082 (flags
& BTRFS_EXTENT_FLAG_DATA
)) {
4083 rc
->found_file_extent
= 1;
4084 ret
= relocate_data_extent(rc
->data_inode
,
4085 &key
, &rc
->cluster
);
4092 if (trans
&& progress
&& err
== -ENOSPC
) {
4093 ret
= btrfs_force_chunk_alloc(trans
, rc
->block_group
->flags
);
4101 btrfs_release_path(path
);
4102 clear_extent_bits(&rc
->processed_blocks
, 0, (u64
)-1, EXTENT_DIRTY
);
4105 btrfs_end_transaction_throttle(trans
);
4106 btrfs_btree_balance_dirty(fs_info
);
4110 ret
= relocate_file_extent_cluster(rc
->data_inode
,
4116 rc
->create_reloc_tree
= 0;
4117 set_reloc_control(rc
);
4119 backref_cache_cleanup(&rc
->backref_cache
);
4120 btrfs_block_rsv_release(fs_info
, rc
->block_rsv
, (u64
)-1);
4122 err
= prepare_to_merge(rc
, err
);
4124 merge_reloc_roots(rc
);
4126 rc
->merge_reloc_tree
= 0;
4127 unset_reloc_control(rc
);
4128 btrfs_block_rsv_release(fs_info
, rc
->block_rsv
, (u64
)-1);
4130 /* get rid of pinned extents */
4131 trans
= btrfs_join_transaction(rc
->extent_root
);
4132 if (IS_ERR(trans
)) {
4133 err
= PTR_ERR(trans
);
4136 btrfs_commit_transaction(trans
);
4137 ret
= clean_dirty_subvols(rc
);
4138 if (ret
< 0 && !err
)
4141 btrfs_free_block_rsv(fs_info
, rc
->block_rsv
);
4142 btrfs_free_path(path
);
4146 static int __insert_orphan_inode(struct btrfs_trans_handle
*trans
,
4147 struct btrfs_root
*root
, u64 objectid
)
4149 struct btrfs_path
*path
;
4150 struct btrfs_inode_item
*item
;
4151 struct extent_buffer
*leaf
;
4154 path
= btrfs_alloc_path();
4158 ret
= btrfs_insert_empty_inode(trans
, root
, path
, objectid
);
4162 leaf
= path
->nodes
[0];
4163 item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_inode_item
);
4164 memzero_extent_buffer(leaf
, (unsigned long)item
, sizeof(*item
));
4165 btrfs_set_inode_generation(leaf
, item
, 1);
4166 btrfs_set_inode_size(leaf
, item
, 0);
4167 btrfs_set_inode_mode(leaf
, item
, S_IFREG
| 0600);
4168 btrfs_set_inode_flags(leaf
, item
, BTRFS_INODE_NOCOMPRESS
|
4169 BTRFS_INODE_PREALLOC
);
4170 btrfs_mark_buffer_dirty(leaf
);
4172 btrfs_free_path(path
);
4177 * helper to create inode for data relocation.
4178 * the inode is in data relocation tree and its link count is 0
4180 static noinline_for_stack
4181 struct inode
*create_reloc_inode(struct btrfs_fs_info
*fs_info
,
4182 struct btrfs_block_group_cache
*group
)
4184 struct inode
*inode
= NULL
;
4185 struct btrfs_trans_handle
*trans
;
4186 struct btrfs_root
*root
;
4187 struct btrfs_key key
;
4191 root
= read_fs_root(fs_info
, BTRFS_DATA_RELOC_TREE_OBJECTID
);
4193 return ERR_CAST(root
);
4195 trans
= btrfs_start_transaction(root
, 6);
4197 return ERR_CAST(trans
);
4199 err
= btrfs_find_free_objectid(root
, &objectid
);
4203 err
= __insert_orphan_inode(trans
, root
, objectid
);
4206 key
.objectid
= objectid
;
4207 key
.type
= BTRFS_INODE_ITEM_KEY
;
4209 inode
= btrfs_iget(fs_info
->sb
, &key
, root
, NULL
);
4210 BUG_ON(IS_ERR(inode
));
4211 BTRFS_I(inode
)->index_cnt
= group
->key
.objectid
;
4213 err
= btrfs_orphan_add(trans
, BTRFS_I(inode
));
4215 btrfs_end_transaction(trans
);
4216 btrfs_btree_balance_dirty(fs_info
);
4220 inode
= ERR_PTR(err
);
4225 static struct reloc_control
*alloc_reloc_control(void)
4227 struct reloc_control
*rc
;
4229 rc
= kzalloc(sizeof(*rc
), GFP_NOFS
);
4233 INIT_LIST_HEAD(&rc
->reloc_roots
);
4234 INIT_LIST_HEAD(&rc
->dirty_subvol_roots
);
4235 backref_cache_init(&rc
->backref_cache
);
4236 mapping_tree_init(&rc
->reloc_root_tree
);
4237 extent_io_tree_init(&rc
->processed_blocks
, NULL
);
4242 * Print the block group being relocated
4244 static void describe_relocation(struct btrfs_fs_info
*fs_info
,
4245 struct btrfs_block_group_cache
*block_group
)
4247 char buf
[128] = {'\0'};
4249 btrfs_describe_block_groups(block_group
->flags
, buf
, sizeof(buf
));
4252 "relocating block group %llu flags %s",
4253 block_group
->key
.objectid
, buf
);
4257 * function to relocate all extents in a block group.
4259 int btrfs_relocate_block_group(struct btrfs_fs_info
*fs_info
, u64 group_start
)
4261 struct btrfs_block_group_cache
*bg
;
4262 struct btrfs_root
*extent_root
= fs_info
->extent_root
;
4263 struct reloc_control
*rc
;
4264 struct inode
*inode
;
4265 struct btrfs_path
*path
;
4270 bg
= btrfs_lookup_block_group(fs_info
, group_start
);
4274 if (btrfs_pinned_by_swapfile(fs_info
, bg
)) {
4275 btrfs_put_block_group(bg
);
4279 rc
= alloc_reloc_control();
4281 btrfs_put_block_group(bg
);
4285 rc
->extent_root
= extent_root
;
4286 rc
->block_group
= bg
;
4288 ret
= btrfs_inc_block_group_ro(rc
->block_group
);
4295 path
= btrfs_alloc_path();
4301 inode
= lookup_free_space_inode(fs_info
, rc
->block_group
, path
);
4302 btrfs_free_path(path
);
4305 ret
= delete_block_group_cache(fs_info
, rc
->block_group
, inode
, 0);
4307 ret
= PTR_ERR(inode
);
4309 if (ret
&& ret
!= -ENOENT
) {
4314 rc
->data_inode
= create_reloc_inode(fs_info
, rc
->block_group
);
4315 if (IS_ERR(rc
->data_inode
)) {
4316 err
= PTR_ERR(rc
->data_inode
);
4317 rc
->data_inode
= NULL
;
4321 describe_relocation(fs_info
, rc
->block_group
);
4323 btrfs_wait_block_group_reservations(rc
->block_group
);
4324 btrfs_wait_nocow_writers(rc
->block_group
);
4325 btrfs_wait_ordered_roots(fs_info
, U64_MAX
,
4326 rc
->block_group
->key
.objectid
,
4327 rc
->block_group
->key
.offset
);
4330 mutex_lock(&fs_info
->cleaner_mutex
);
4331 ret
= relocate_block_group(rc
);
4332 mutex_unlock(&fs_info
->cleaner_mutex
);
4338 if (rc
->extents_found
== 0)
4341 btrfs_info(fs_info
, "found %llu extents", rc
->extents_found
);
4343 if (rc
->stage
== MOVE_DATA_EXTENTS
&& rc
->found_file_extent
) {
4344 ret
= btrfs_wait_ordered_range(rc
->data_inode
, 0,
4350 invalidate_mapping_pages(rc
->data_inode
->i_mapping
,
4352 rc
->stage
= UPDATE_DATA_PTRS
;
4356 WARN_ON(rc
->block_group
->pinned
> 0);
4357 WARN_ON(rc
->block_group
->reserved
> 0);
4358 WARN_ON(btrfs_block_group_used(&rc
->block_group
->item
) > 0);
4361 btrfs_dec_block_group_ro(rc
->block_group
);
4362 iput(rc
->data_inode
);
4363 btrfs_put_block_group(rc
->block_group
);
4368 static noinline_for_stack
int mark_garbage_root(struct btrfs_root
*root
)
4370 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
4371 struct btrfs_trans_handle
*trans
;
4374 trans
= btrfs_start_transaction(fs_info
->tree_root
, 0);
4376 return PTR_ERR(trans
);
4378 memset(&root
->root_item
.drop_progress
, 0,
4379 sizeof(root
->root_item
.drop_progress
));
4380 root
->root_item
.drop_level
= 0;
4381 btrfs_set_root_refs(&root
->root_item
, 0);
4382 ret
= btrfs_update_root(trans
, fs_info
->tree_root
,
4383 &root
->root_key
, &root
->root_item
);
4385 err
= btrfs_end_transaction(trans
);
4392 * recover relocation interrupted by system crash.
4394 * this function resumes merging reloc trees with corresponding fs trees.
4395 * this is important for keeping the sharing of tree blocks
4397 int btrfs_recover_relocation(struct btrfs_root
*root
)
4399 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
4400 LIST_HEAD(reloc_roots
);
4401 struct btrfs_key key
;
4402 struct btrfs_root
*fs_root
;
4403 struct btrfs_root
*reloc_root
;
4404 struct btrfs_path
*path
;
4405 struct extent_buffer
*leaf
;
4406 struct reloc_control
*rc
= NULL
;
4407 struct btrfs_trans_handle
*trans
;
4411 path
= btrfs_alloc_path();
4414 path
->reada
= READA_BACK
;
4416 key
.objectid
= BTRFS_TREE_RELOC_OBJECTID
;
4417 key
.type
= BTRFS_ROOT_ITEM_KEY
;
4418 key
.offset
= (u64
)-1;
4421 ret
= btrfs_search_slot(NULL
, fs_info
->tree_root
, &key
,
4428 if (path
->slots
[0] == 0)
4432 leaf
= path
->nodes
[0];
4433 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
4434 btrfs_release_path(path
);
4436 if (key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
||
4437 key
.type
!= BTRFS_ROOT_ITEM_KEY
)
4440 reloc_root
= btrfs_read_fs_root(root
, &key
);
4441 if (IS_ERR(reloc_root
)) {
4442 err
= PTR_ERR(reloc_root
);
4446 list_add(&reloc_root
->root_list
, &reloc_roots
);
4448 if (btrfs_root_refs(&reloc_root
->root_item
) > 0) {
4449 fs_root
= read_fs_root(fs_info
,
4450 reloc_root
->root_key
.offset
);
4451 if (IS_ERR(fs_root
)) {
4452 ret
= PTR_ERR(fs_root
);
4453 if (ret
!= -ENOENT
) {
4457 ret
= mark_garbage_root(reloc_root
);
4465 if (key
.offset
== 0)
4470 btrfs_release_path(path
);
4472 if (list_empty(&reloc_roots
))
4475 rc
= alloc_reloc_control();
4481 rc
->extent_root
= fs_info
->extent_root
;
4483 set_reloc_control(rc
);
4485 trans
= btrfs_join_transaction(rc
->extent_root
);
4486 if (IS_ERR(trans
)) {
4487 unset_reloc_control(rc
);
4488 err
= PTR_ERR(trans
);
4492 rc
->merge_reloc_tree
= 1;
4494 while (!list_empty(&reloc_roots
)) {
4495 reloc_root
= list_entry(reloc_roots
.next
,
4496 struct btrfs_root
, root_list
);
4497 list_del(&reloc_root
->root_list
);
4499 if (btrfs_root_refs(&reloc_root
->root_item
) == 0) {
4500 list_add_tail(&reloc_root
->root_list
,
4505 fs_root
= read_fs_root(fs_info
, reloc_root
->root_key
.offset
);
4506 if (IS_ERR(fs_root
)) {
4507 err
= PTR_ERR(fs_root
);
4511 err
= __add_reloc_root(reloc_root
);
4512 BUG_ON(err
< 0); /* -ENOMEM or logic error */
4513 fs_root
->reloc_root
= reloc_root
;
4516 err
= btrfs_commit_transaction(trans
);
4520 merge_reloc_roots(rc
);
4522 unset_reloc_control(rc
);
4524 trans
= btrfs_join_transaction(rc
->extent_root
);
4525 if (IS_ERR(trans
)) {
4526 err
= PTR_ERR(trans
);
4529 err
= btrfs_commit_transaction(trans
);
4531 ret
= clean_dirty_subvols(rc
);
4532 if (ret
< 0 && !err
)
4537 if (!list_empty(&reloc_roots
))
4538 free_reloc_roots(&reloc_roots
);
4540 btrfs_free_path(path
);
4543 /* cleanup orphan inode in data relocation tree */
4544 fs_root
= read_fs_root(fs_info
, BTRFS_DATA_RELOC_TREE_OBJECTID
);
4545 if (IS_ERR(fs_root
))
4546 err
= PTR_ERR(fs_root
);
4548 err
= btrfs_orphan_cleanup(fs_root
);
4554 * helper to add ordered checksum for data relocation.
4556 * cloning checksum properly handles the nodatasum extents.
4557 * it also saves CPU time to re-calculate the checksum.
4559 int btrfs_reloc_clone_csums(struct inode
*inode
, u64 file_pos
, u64 len
)
4561 struct btrfs_fs_info
*fs_info
= btrfs_sb(inode
->i_sb
);
4562 struct btrfs_ordered_sum
*sums
;
4563 struct btrfs_ordered_extent
*ordered
;
4569 ordered
= btrfs_lookup_ordered_extent(inode
, file_pos
);
4570 BUG_ON(ordered
->file_offset
!= file_pos
|| ordered
->len
!= len
);
4572 disk_bytenr
= file_pos
+ BTRFS_I(inode
)->index_cnt
;
4573 ret
= btrfs_lookup_csums_range(fs_info
->csum_root
, disk_bytenr
,
4574 disk_bytenr
+ len
- 1, &list
, 0);
4578 while (!list_empty(&list
)) {
4579 sums
= list_entry(list
.next
, struct btrfs_ordered_sum
, list
);
4580 list_del_init(&sums
->list
);
4583 * We need to offset the new_bytenr based on where the csum is.
4584 * We need to do this because we will read in entire prealloc
4585 * extents but we may have written to say the middle of the
4586 * prealloc extent, so we need to make sure the csum goes with
4587 * the right disk offset.
4589 * We can do this because the data reloc inode refers strictly
4590 * to the on disk bytes, so we don't have to worry about
4591 * disk_len vs real len like with real inodes since it's all
4594 new_bytenr
= ordered
->start
+ (sums
->bytenr
- disk_bytenr
);
4595 sums
->bytenr
= new_bytenr
;
4597 btrfs_add_ordered_sum(inode
, ordered
, sums
);
4600 btrfs_put_ordered_extent(ordered
);
4604 int btrfs_reloc_cow_block(struct btrfs_trans_handle
*trans
,
4605 struct btrfs_root
*root
, struct extent_buffer
*buf
,
4606 struct extent_buffer
*cow
)
4608 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
4609 struct reloc_control
*rc
;
4610 struct backref_node
*node
;
4615 rc
= fs_info
->reloc_ctl
;
4619 BUG_ON(rc
->stage
== UPDATE_DATA_PTRS
&&
4620 root
->root_key
.objectid
== BTRFS_DATA_RELOC_TREE_OBJECTID
);
4622 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
) {
4623 if (buf
== root
->node
)
4624 __update_reloc_root(root
, cow
->start
);
4627 level
= btrfs_header_level(buf
);
4628 if (btrfs_header_generation(buf
) <=
4629 btrfs_root_last_snapshot(&root
->root_item
))
4632 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
&&
4633 rc
->create_reloc_tree
) {
4634 WARN_ON(!first_cow
&& level
== 0);
4636 node
= rc
->backref_cache
.path
[level
];
4637 BUG_ON(node
->bytenr
!= buf
->start
&&
4638 node
->new_bytenr
!= buf
->start
);
4640 drop_node_buffer(node
);
4641 extent_buffer_get(cow
);
4643 node
->new_bytenr
= cow
->start
;
4645 if (!node
->pending
) {
4646 list_move_tail(&node
->list
,
4647 &rc
->backref_cache
.pending
[level
]);
4652 __mark_block_processed(rc
, node
);
4654 if (first_cow
&& level
> 0)
4655 rc
->nodes_relocated
+= buf
->len
;
4658 if (level
== 0 && first_cow
&& rc
->stage
== UPDATE_DATA_PTRS
)
4659 ret
= replace_file_extents(trans
, rc
, root
, cow
);
4664 * called before creating snapshot. it calculates metadata reservation
4665 * required for relocating tree blocks in the snapshot
4667 void btrfs_reloc_pre_snapshot(struct btrfs_pending_snapshot
*pending
,
4668 u64
*bytes_to_reserve
)
4670 struct btrfs_root
*root
;
4671 struct reloc_control
*rc
;
4673 root
= pending
->root
;
4674 if (!root
->reloc_root
)
4677 rc
= root
->fs_info
->reloc_ctl
;
4678 if (!rc
->merge_reloc_tree
)
4681 root
= root
->reloc_root
;
4682 BUG_ON(btrfs_root_refs(&root
->root_item
) == 0);
4684 * relocation is in the stage of merging trees. the space
4685 * used by merging a reloc tree is twice the size of
4686 * relocated tree nodes in the worst case. half for cowing
4687 * the reloc tree, half for cowing the fs tree. the space
4688 * used by cowing the reloc tree will be freed after the
4689 * tree is dropped. if we create snapshot, cowing the fs
4690 * tree may use more space than it frees. so we need
4691 * reserve extra space.
4693 *bytes_to_reserve
+= rc
->nodes_relocated
;
4697 * called after snapshot is created. migrate block reservation
4698 * and create reloc root for the newly created snapshot
4700 int btrfs_reloc_post_snapshot(struct btrfs_trans_handle
*trans
,
4701 struct btrfs_pending_snapshot
*pending
)
4703 struct btrfs_root
*root
= pending
->root
;
4704 struct btrfs_root
*reloc_root
;
4705 struct btrfs_root
*new_root
;
4706 struct reloc_control
*rc
;
4709 if (!root
->reloc_root
)
4712 rc
= root
->fs_info
->reloc_ctl
;
4713 rc
->merging_rsv_size
+= rc
->nodes_relocated
;
4715 if (rc
->merge_reloc_tree
) {
4716 ret
= btrfs_block_rsv_migrate(&pending
->block_rsv
,
4718 rc
->nodes_relocated
, true);
4723 new_root
= pending
->snap
;
4724 reloc_root
= create_reloc_root(trans
, root
->reloc_root
,
4725 new_root
->root_key
.objectid
);
4726 if (IS_ERR(reloc_root
))
4727 return PTR_ERR(reloc_root
);
4729 ret
= __add_reloc_root(reloc_root
);
4731 new_root
->reloc_root
= reloc_root
;
4733 if (rc
->create_reloc_tree
)
4734 ret
= clone_backref_node(trans
, rc
, root
, reloc_root
);