2 * Copyright (C) 2009 Oracle. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
19 #include <linux/sched.h>
20 #include <linux/pagemap.h>
21 #include <linux/writeback.h>
22 #include <linux/blkdev.h>
23 #include <linux/rbtree.h>
24 #include <linux/slab.h>
27 #include "transaction.h"
30 #include "btrfs_inode.h"
31 #include "async-thread.h"
32 #include "free-space-cache.h"
33 #include "inode-map.h"
36 * backref_node, mapping_node and tree_block start with this
39 struct rb_node rb_node
;
44 * present a tree block in the backref cache
47 struct rb_node rb_node
;
51 /* objectid of tree block owner, can be not uptodate */
53 /* link to pending, changed or detached list */
54 struct list_head list
;
55 /* list of upper level blocks reference this block */
56 struct list_head upper
;
57 /* list of child blocks in the cache */
58 struct list_head lower
;
59 /* NULL if this node is not tree root */
60 struct btrfs_root
*root
;
61 /* extent buffer got by COW the block */
62 struct extent_buffer
*eb
;
63 /* level of tree block */
65 /* is the block in non-reference counted tree */
66 unsigned int cowonly
:1;
67 /* 1 if no child node in the cache */
68 unsigned int lowest
:1;
69 /* is the extent buffer locked */
70 unsigned int locked
:1;
71 /* has the block been processed */
72 unsigned int processed
:1;
73 /* have backrefs of this block been checked */
74 unsigned int checked
:1;
76 * 1 if corresponding block has been cowed but some upper
77 * level block pointers may not point to the new location
79 unsigned int pending
:1;
81 * 1 if the backref node isn't connected to any other
84 unsigned int detached
:1;
88 * present a block pointer in the backref cache
91 struct list_head list
[2];
92 struct backref_node
*node
[2];
98 struct backref_cache
{
99 /* red black tree of all backref nodes in the cache */
100 struct rb_root rb_root
;
101 /* for passing backref nodes to btrfs_reloc_cow_block */
102 struct backref_node
*path
[BTRFS_MAX_LEVEL
];
104 * list of blocks that have been cowed but some block
105 * pointers in upper level blocks may not reflect the
108 struct list_head pending
[BTRFS_MAX_LEVEL
];
109 /* list of backref nodes with no child node */
110 struct list_head leaves
;
111 /* list of blocks that have been cowed in current transaction */
112 struct list_head changed
;
113 /* list of detached backref node. */
114 struct list_head detached
;
123 * map address of tree root to tree
125 struct mapping_node
{
126 struct rb_node rb_node
;
131 struct mapping_tree
{
132 struct rb_root rb_root
;
137 * present a tree block to process
140 struct rb_node rb_node
;
142 struct btrfs_key key
;
143 unsigned int level
:8;
144 unsigned int key_ready
:1;
147 #define MAX_EXTENTS 128
149 struct file_extent_cluster
{
152 u64 boundary
[MAX_EXTENTS
];
156 struct reloc_control
{
157 /* block group to relocate */
158 struct btrfs_block_group_cache
*block_group
;
160 struct btrfs_root
*extent_root
;
161 /* inode for moving data */
162 struct inode
*data_inode
;
164 struct btrfs_block_rsv
*block_rsv
;
166 struct backref_cache backref_cache
;
168 struct file_extent_cluster cluster
;
169 /* tree blocks have been processed */
170 struct extent_io_tree processed_blocks
;
171 /* map start of tree root to corresponding reloc tree */
172 struct mapping_tree reloc_root_tree
;
173 /* list of reloc trees */
174 struct list_head reloc_roots
;
175 /* size of metadata reservation for merging reloc trees */
176 u64 merging_rsv_size
;
177 /* size of relocated tree nodes */
183 unsigned int stage
:8;
184 unsigned int create_reloc_tree
:1;
185 unsigned int merge_reloc_tree
:1;
186 unsigned int found_file_extent
:1;
187 unsigned int commit_transaction
:1;
190 /* stages of data relocation */
191 #define MOVE_DATA_EXTENTS 0
192 #define UPDATE_DATA_PTRS 1
194 static void remove_backref_node(struct backref_cache
*cache
,
195 struct backref_node
*node
);
196 static void __mark_block_processed(struct reloc_control
*rc
,
197 struct backref_node
*node
);
199 static void mapping_tree_init(struct mapping_tree
*tree
)
201 tree
->rb_root
= RB_ROOT
;
202 spin_lock_init(&tree
->lock
);
205 static void backref_cache_init(struct backref_cache
*cache
)
208 cache
->rb_root
= RB_ROOT
;
209 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++)
210 INIT_LIST_HEAD(&cache
->pending
[i
]);
211 INIT_LIST_HEAD(&cache
->changed
);
212 INIT_LIST_HEAD(&cache
->detached
);
213 INIT_LIST_HEAD(&cache
->leaves
);
216 static void backref_cache_cleanup(struct backref_cache
*cache
)
218 struct backref_node
*node
;
221 while (!list_empty(&cache
->detached
)) {
222 node
= list_entry(cache
->detached
.next
,
223 struct backref_node
, list
);
224 remove_backref_node(cache
, node
);
227 while (!list_empty(&cache
->leaves
)) {
228 node
= list_entry(cache
->leaves
.next
,
229 struct backref_node
, lower
);
230 remove_backref_node(cache
, node
);
233 cache
->last_trans
= 0;
235 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++)
236 BUG_ON(!list_empty(&cache
->pending
[i
]));
237 BUG_ON(!list_empty(&cache
->changed
));
238 BUG_ON(!list_empty(&cache
->detached
));
239 BUG_ON(!RB_EMPTY_ROOT(&cache
->rb_root
));
240 BUG_ON(cache
->nr_nodes
);
241 BUG_ON(cache
->nr_edges
);
244 static struct backref_node
*alloc_backref_node(struct backref_cache
*cache
)
246 struct backref_node
*node
;
248 node
= kzalloc(sizeof(*node
), GFP_NOFS
);
250 INIT_LIST_HEAD(&node
->list
);
251 INIT_LIST_HEAD(&node
->upper
);
252 INIT_LIST_HEAD(&node
->lower
);
253 RB_CLEAR_NODE(&node
->rb_node
);
259 static void free_backref_node(struct backref_cache
*cache
,
260 struct backref_node
*node
)
268 static struct backref_edge
*alloc_backref_edge(struct backref_cache
*cache
)
270 struct backref_edge
*edge
;
272 edge
= kzalloc(sizeof(*edge
), GFP_NOFS
);
278 static void free_backref_edge(struct backref_cache
*cache
,
279 struct backref_edge
*edge
)
287 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 bytenr
,
288 struct rb_node
*node
)
290 struct rb_node
**p
= &root
->rb_node
;
291 struct rb_node
*parent
= NULL
;
292 struct tree_entry
*entry
;
296 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
298 if (bytenr
< entry
->bytenr
)
300 else if (bytenr
> entry
->bytenr
)
306 rb_link_node(node
, parent
, p
);
307 rb_insert_color(node
, root
);
311 static struct rb_node
*tree_search(struct rb_root
*root
, u64 bytenr
)
313 struct rb_node
*n
= root
->rb_node
;
314 struct tree_entry
*entry
;
317 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
319 if (bytenr
< entry
->bytenr
)
321 else if (bytenr
> entry
->bytenr
)
329 static void backref_tree_panic(struct rb_node
*rb_node
, int errno
, u64 bytenr
)
332 struct btrfs_fs_info
*fs_info
= NULL
;
333 struct backref_node
*bnode
= rb_entry(rb_node
, struct backref_node
,
336 fs_info
= bnode
->root
->fs_info
;
337 btrfs_panic(fs_info
, errno
, "Inconsistency in backref cache "
338 "found at offset %llu\n", (unsigned long long)bytenr
);
342 * walk up backref nodes until reach node presents tree root
344 static struct backref_node
*walk_up_backref(struct backref_node
*node
,
345 struct backref_edge
*edges
[],
348 struct backref_edge
*edge
;
351 while (!list_empty(&node
->upper
)) {
352 edge
= list_entry(node
->upper
.next
,
353 struct backref_edge
, list
[LOWER
]);
355 node
= edge
->node
[UPPER
];
357 BUG_ON(node
->detached
);
363 * walk down backref nodes to find start of next reference path
365 static struct backref_node
*walk_down_backref(struct backref_edge
*edges
[],
368 struct backref_edge
*edge
;
369 struct backref_node
*lower
;
373 edge
= edges
[idx
- 1];
374 lower
= edge
->node
[LOWER
];
375 if (list_is_last(&edge
->list
[LOWER
], &lower
->upper
)) {
379 edge
= list_entry(edge
->list
[LOWER
].next
,
380 struct backref_edge
, list
[LOWER
]);
381 edges
[idx
- 1] = edge
;
383 return edge
->node
[UPPER
];
389 static void unlock_node_buffer(struct backref_node
*node
)
392 btrfs_tree_unlock(node
->eb
);
397 static void drop_node_buffer(struct backref_node
*node
)
400 unlock_node_buffer(node
);
401 free_extent_buffer(node
->eb
);
406 static void drop_backref_node(struct backref_cache
*tree
,
407 struct backref_node
*node
)
409 BUG_ON(!list_empty(&node
->upper
));
411 drop_node_buffer(node
);
412 list_del(&node
->list
);
413 list_del(&node
->lower
);
414 if (!RB_EMPTY_NODE(&node
->rb_node
))
415 rb_erase(&node
->rb_node
, &tree
->rb_root
);
416 free_backref_node(tree
, node
);
420 * remove a backref node from the backref cache
422 static void remove_backref_node(struct backref_cache
*cache
,
423 struct backref_node
*node
)
425 struct backref_node
*upper
;
426 struct backref_edge
*edge
;
431 BUG_ON(!node
->lowest
&& !node
->detached
);
432 while (!list_empty(&node
->upper
)) {
433 edge
= list_entry(node
->upper
.next
, struct backref_edge
,
435 upper
= edge
->node
[UPPER
];
436 list_del(&edge
->list
[LOWER
]);
437 list_del(&edge
->list
[UPPER
]);
438 free_backref_edge(cache
, edge
);
440 if (RB_EMPTY_NODE(&upper
->rb_node
)) {
441 BUG_ON(!list_empty(&node
->upper
));
442 drop_backref_node(cache
, node
);
448 * add the node to leaf node list if no other
449 * child block cached.
451 if (list_empty(&upper
->lower
)) {
452 list_add_tail(&upper
->lower
, &cache
->leaves
);
457 drop_backref_node(cache
, node
);
460 static void update_backref_node(struct backref_cache
*cache
,
461 struct backref_node
*node
, u64 bytenr
)
463 struct rb_node
*rb_node
;
464 rb_erase(&node
->rb_node
, &cache
->rb_root
);
465 node
->bytenr
= bytenr
;
466 rb_node
= tree_insert(&cache
->rb_root
, node
->bytenr
, &node
->rb_node
);
468 backref_tree_panic(rb_node
, -EEXIST
, bytenr
);
472 * update backref cache after a transaction commit
474 static int update_backref_cache(struct btrfs_trans_handle
*trans
,
475 struct backref_cache
*cache
)
477 struct backref_node
*node
;
480 if (cache
->last_trans
== 0) {
481 cache
->last_trans
= trans
->transid
;
485 if (cache
->last_trans
== trans
->transid
)
489 * detached nodes are used to avoid unnecessary backref
490 * lookup. transaction commit changes the extent tree.
491 * so the detached nodes are no longer useful.
493 while (!list_empty(&cache
->detached
)) {
494 node
= list_entry(cache
->detached
.next
,
495 struct backref_node
, list
);
496 remove_backref_node(cache
, node
);
499 while (!list_empty(&cache
->changed
)) {
500 node
= list_entry(cache
->changed
.next
,
501 struct backref_node
, list
);
502 list_del_init(&node
->list
);
503 BUG_ON(node
->pending
);
504 update_backref_node(cache
, node
, node
->new_bytenr
);
508 * some nodes can be left in the pending list if there were
509 * errors during processing the pending nodes.
511 for (level
= 0; level
< BTRFS_MAX_LEVEL
; level
++) {
512 list_for_each_entry(node
, &cache
->pending
[level
], list
) {
513 BUG_ON(!node
->pending
);
514 if (node
->bytenr
== node
->new_bytenr
)
516 update_backref_node(cache
, node
, node
->new_bytenr
);
520 cache
->last_trans
= 0;
525 static int should_ignore_root(struct btrfs_root
*root
)
527 struct btrfs_root
*reloc_root
;
532 reloc_root
= root
->reloc_root
;
536 if (btrfs_root_last_snapshot(&reloc_root
->root_item
) ==
537 root
->fs_info
->running_transaction
->transid
- 1)
540 * if there is reloc tree and it was created in previous
541 * transaction backref lookup can find the reloc tree,
542 * so backref node for the fs tree root is useless for
548 * find reloc tree by address of tree root
550 static struct btrfs_root
*find_reloc_root(struct reloc_control
*rc
,
553 struct rb_node
*rb_node
;
554 struct mapping_node
*node
;
555 struct btrfs_root
*root
= NULL
;
557 spin_lock(&rc
->reloc_root_tree
.lock
);
558 rb_node
= tree_search(&rc
->reloc_root_tree
.rb_root
, bytenr
);
560 node
= rb_entry(rb_node
, struct mapping_node
, rb_node
);
561 root
= (struct btrfs_root
*)node
->data
;
563 spin_unlock(&rc
->reloc_root_tree
.lock
);
567 static int is_cowonly_root(u64 root_objectid
)
569 if (root_objectid
== BTRFS_ROOT_TREE_OBJECTID
||
570 root_objectid
== BTRFS_EXTENT_TREE_OBJECTID
||
571 root_objectid
== BTRFS_CHUNK_TREE_OBJECTID
||
572 root_objectid
== BTRFS_DEV_TREE_OBJECTID
||
573 root_objectid
== BTRFS_TREE_LOG_OBJECTID
||
574 root_objectid
== BTRFS_CSUM_TREE_OBJECTID
)
579 static struct btrfs_root
*read_fs_root(struct btrfs_fs_info
*fs_info
,
582 struct btrfs_key key
;
584 key
.objectid
= root_objectid
;
585 key
.type
= BTRFS_ROOT_ITEM_KEY
;
586 if (is_cowonly_root(root_objectid
))
589 key
.offset
= (u64
)-1;
591 return btrfs_read_fs_root_no_name(fs_info
, &key
);
594 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
595 static noinline_for_stack
596 struct btrfs_root
*find_tree_root(struct reloc_control
*rc
,
597 struct extent_buffer
*leaf
,
598 struct btrfs_extent_ref_v0
*ref0
)
600 struct btrfs_root
*root
;
601 u64 root_objectid
= btrfs_ref_root_v0(leaf
, ref0
);
602 u64 generation
= btrfs_ref_generation_v0(leaf
, ref0
);
604 BUG_ON(root_objectid
== BTRFS_TREE_RELOC_OBJECTID
);
606 root
= read_fs_root(rc
->extent_root
->fs_info
, root_objectid
);
607 BUG_ON(IS_ERR(root
));
609 if (root
->ref_cows
&&
610 generation
!= btrfs_root_generation(&root
->root_item
))
617 static noinline_for_stack
618 int find_inline_backref(struct extent_buffer
*leaf
, int slot
,
619 unsigned long *ptr
, unsigned long *end
)
621 struct btrfs_key key
;
622 struct btrfs_extent_item
*ei
;
623 struct btrfs_tree_block_info
*bi
;
626 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
628 item_size
= btrfs_item_size_nr(leaf
, slot
);
629 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
630 if (item_size
< sizeof(*ei
)) {
631 WARN_ON(item_size
!= sizeof(struct btrfs_extent_item_v0
));
635 ei
= btrfs_item_ptr(leaf
, slot
, struct btrfs_extent_item
);
636 WARN_ON(!(btrfs_extent_flags(leaf
, ei
) &
637 BTRFS_EXTENT_FLAG_TREE_BLOCK
));
639 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
640 item_size
<= sizeof(*ei
) + sizeof(*bi
)) {
641 WARN_ON(item_size
< sizeof(*ei
) + sizeof(*bi
));
645 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
) {
646 bi
= (struct btrfs_tree_block_info
*)(ei
+ 1);
647 *ptr
= (unsigned long)(bi
+ 1);
649 *ptr
= (unsigned long)(ei
+ 1);
651 *end
= (unsigned long)ei
+ item_size
;
656 * build backref tree for a given tree block. root of the backref tree
657 * corresponds the tree block, leaves of the backref tree correspond
658 * roots of b-trees that reference the tree block.
660 * the basic idea of this function is check backrefs of a given block
661 * to find upper level blocks that refernece the block, and then check
662 * bakcrefs of these upper level blocks recursively. the recursion stop
663 * when tree root is reached or backrefs for the block is cached.
665 * NOTE: if we find backrefs for a block are cached, we know backrefs
666 * for all upper level blocks that directly/indirectly reference the
667 * block are also cached.
669 static noinline_for_stack
670 struct backref_node
*build_backref_tree(struct reloc_control
*rc
,
671 struct btrfs_key
*node_key
,
672 int level
, u64 bytenr
)
674 struct backref_cache
*cache
= &rc
->backref_cache
;
675 struct btrfs_path
*path1
;
676 struct btrfs_path
*path2
;
677 struct extent_buffer
*eb
;
678 struct btrfs_root
*root
;
679 struct backref_node
*cur
;
680 struct backref_node
*upper
;
681 struct backref_node
*lower
;
682 struct backref_node
*node
= NULL
;
683 struct backref_node
*exist
= NULL
;
684 struct backref_edge
*edge
;
685 struct rb_node
*rb_node
;
686 struct btrfs_key key
;
695 path1
= btrfs_alloc_path();
696 path2
= btrfs_alloc_path();
697 if (!path1
|| !path2
) {
704 node
= alloc_backref_node(cache
);
710 node
->bytenr
= bytenr
;
717 key
.objectid
= cur
->bytenr
;
718 key
.type
= BTRFS_METADATA_ITEM_KEY
;
719 key
.offset
= (u64
)-1;
721 path1
->search_commit_root
= 1;
722 path1
->skip_locking
= 1;
723 ret
= btrfs_search_slot(NULL
, rc
->extent_root
, &key
, path1
,
729 BUG_ON(!ret
|| !path1
->slots
[0]);
733 WARN_ON(cur
->checked
);
734 if (!list_empty(&cur
->upper
)) {
736 * the backref was added previously when processing
737 * backref of type BTRFS_TREE_BLOCK_REF_KEY
739 BUG_ON(!list_is_singular(&cur
->upper
));
740 edge
= list_entry(cur
->upper
.next
, struct backref_edge
,
742 BUG_ON(!list_empty(&edge
->list
[UPPER
]));
743 exist
= edge
->node
[UPPER
];
745 * add the upper level block to pending list if we need
749 list_add_tail(&edge
->list
[UPPER
], &list
);
756 eb
= path1
->nodes
[0];
759 if (path1
->slots
[0] >= btrfs_header_nritems(eb
)) {
760 ret
= btrfs_next_leaf(rc
->extent_root
, path1
);
767 eb
= path1
->nodes
[0];
770 btrfs_item_key_to_cpu(eb
, &key
, path1
->slots
[0]);
771 if (key
.objectid
!= cur
->bytenr
) {
776 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
||
777 key
.type
== BTRFS_METADATA_ITEM_KEY
) {
778 ret
= find_inline_backref(eb
, path1
->slots
[0],
786 /* update key for inline back ref */
787 struct btrfs_extent_inline_ref
*iref
;
788 iref
= (struct btrfs_extent_inline_ref
*)ptr
;
789 key
.type
= btrfs_extent_inline_ref_type(eb
, iref
);
790 key
.offset
= btrfs_extent_inline_ref_offset(eb
, iref
);
791 WARN_ON(key
.type
!= BTRFS_TREE_BLOCK_REF_KEY
&&
792 key
.type
!= BTRFS_SHARED_BLOCK_REF_KEY
);
796 ((key
.type
== BTRFS_TREE_BLOCK_REF_KEY
&&
797 exist
->owner
== key
.offset
) ||
798 (key
.type
== BTRFS_SHARED_BLOCK_REF_KEY
&&
799 exist
->bytenr
== key
.offset
))) {
804 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
805 if (key
.type
== BTRFS_SHARED_BLOCK_REF_KEY
||
806 key
.type
== BTRFS_EXTENT_REF_V0_KEY
) {
807 if (key
.type
== BTRFS_EXTENT_REF_V0_KEY
) {
808 struct btrfs_extent_ref_v0
*ref0
;
809 ref0
= btrfs_item_ptr(eb
, path1
->slots
[0],
810 struct btrfs_extent_ref_v0
);
811 if (key
.objectid
== key
.offset
) {
812 root
= find_tree_root(rc
, eb
, ref0
);
813 if (root
&& !should_ignore_root(root
))
816 list_add(&cur
->list
, &useless
);
819 if (is_cowonly_root(btrfs_ref_root_v0(eb
,
824 BUG_ON(key
.type
== BTRFS_EXTENT_REF_V0_KEY
);
825 if (key
.type
== BTRFS_SHARED_BLOCK_REF_KEY
) {
827 if (key
.objectid
== key
.offset
) {
829 * only root blocks of reloc trees use
830 * backref of this type.
832 root
= find_reloc_root(rc
, cur
->bytenr
);
838 edge
= alloc_backref_edge(cache
);
843 rb_node
= tree_search(&cache
->rb_root
, key
.offset
);
845 upper
= alloc_backref_node(cache
);
847 free_backref_edge(cache
, edge
);
851 upper
->bytenr
= key
.offset
;
852 upper
->level
= cur
->level
+ 1;
854 * backrefs for the upper level block isn't
855 * cached, add the block to pending list
857 list_add_tail(&edge
->list
[UPPER
], &list
);
859 upper
= rb_entry(rb_node
, struct backref_node
,
861 BUG_ON(!upper
->checked
);
862 INIT_LIST_HEAD(&edge
->list
[UPPER
]);
864 list_add_tail(&edge
->list
[LOWER
], &cur
->upper
);
865 edge
->node
[LOWER
] = cur
;
866 edge
->node
[UPPER
] = upper
;
869 } else if (key
.type
!= BTRFS_TREE_BLOCK_REF_KEY
) {
873 /* key.type == BTRFS_TREE_BLOCK_REF_KEY */
874 root
= read_fs_root(rc
->extent_root
->fs_info
, key
.offset
);
883 if (btrfs_root_level(&root
->root_item
) == cur
->level
) {
885 BUG_ON(btrfs_root_bytenr(&root
->root_item
) !=
887 if (should_ignore_root(root
))
888 list_add(&cur
->list
, &useless
);
894 level
= cur
->level
+ 1;
897 * searching the tree to find upper level blocks
898 * reference the block.
900 path2
->search_commit_root
= 1;
901 path2
->skip_locking
= 1;
902 path2
->lowest_level
= level
;
903 ret
= btrfs_search_slot(NULL
, root
, node_key
, path2
, 0, 0);
904 path2
->lowest_level
= 0;
909 if (ret
> 0 && path2
->slots
[level
] > 0)
910 path2
->slots
[level
]--;
912 eb
= path2
->nodes
[level
];
913 WARN_ON(btrfs_node_blockptr(eb
, path2
->slots
[level
]) !=
917 for (; level
< BTRFS_MAX_LEVEL
; level
++) {
918 if (!path2
->nodes
[level
]) {
919 BUG_ON(btrfs_root_bytenr(&root
->root_item
) !=
921 if (should_ignore_root(root
))
922 list_add(&lower
->list
, &useless
);
928 edge
= alloc_backref_edge(cache
);
934 eb
= path2
->nodes
[level
];
935 rb_node
= tree_search(&cache
->rb_root
, eb
->start
);
937 upper
= alloc_backref_node(cache
);
939 free_backref_edge(cache
, edge
);
943 upper
->bytenr
= eb
->start
;
944 upper
->owner
= btrfs_header_owner(eb
);
945 upper
->level
= lower
->level
+ 1;
950 * if we know the block isn't shared
951 * we can void checking its backrefs.
953 if (btrfs_block_can_be_shared(root
, eb
))
959 * add the block to pending list if we
960 * need check its backrefs. only block
961 * at 'cur->level + 1' is added to the
962 * tail of pending list. this guarantees
963 * we check backrefs from lower level
964 * blocks to upper level blocks.
966 if (!upper
->checked
&&
967 level
== cur
->level
+ 1) {
968 list_add_tail(&edge
->list
[UPPER
],
971 INIT_LIST_HEAD(&edge
->list
[UPPER
]);
973 upper
= rb_entry(rb_node
, struct backref_node
,
975 BUG_ON(!upper
->checked
);
976 INIT_LIST_HEAD(&edge
->list
[UPPER
]);
978 upper
->owner
= btrfs_header_owner(eb
);
980 list_add_tail(&edge
->list
[LOWER
], &lower
->upper
);
981 edge
->node
[LOWER
] = lower
;
982 edge
->node
[UPPER
] = upper
;
989 btrfs_release_path(path2
);
992 ptr
+= btrfs_extent_inline_ref_size(key
.type
);
1002 btrfs_release_path(path1
);
1007 /* the pending list isn't empty, take the first block to process */
1008 if (!list_empty(&list
)) {
1009 edge
= list_entry(list
.next
, struct backref_edge
, list
[UPPER
]);
1010 list_del_init(&edge
->list
[UPPER
]);
1011 cur
= edge
->node
[UPPER
];
1016 * everything goes well, connect backref nodes and insert backref nodes
1019 BUG_ON(!node
->checked
);
1020 cowonly
= node
->cowonly
;
1022 rb_node
= tree_insert(&cache
->rb_root
, node
->bytenr
,
1025 backref_tree_panic(rb_node
, -EEXIST
, node
->bytenr
);
1026 list_add_tail(&node
->lower
, &cache
->leaves
);
1029 list_for_each_entry(edge
, &node
->upper
, list
[LOWER
])
1030 list_add_tail(&edge
->list
[UPPER
], &list
);
1032 while (!list_empty(&list
)) {
1033 edge
= list_entry(list
.next
, struct backref_edge
, list
[UPPER
]);
1034 list_del_init(&edge
->list
[UPPER
]);
1035 upper
= edge
->node
[UPPER
];
1036 if (upper
->detached
) {
1037 list_del(&edge
->list
[LOWER
]);
1038 lower
= edge
->node
[LOWER
];
1039 free_backref_edge(cache
, edge
);
1040 if (list_empty(&lower
->upper
))
1041 list_add(&lower
->list
, &useless
);
1045 if (!RB_EMPTY_NODE(&upper
->rb_node
)) {
1046 if (upper
->lowest
) {
1047 list_del_init(&upper
->lower
);
1051 list_add_tail(&edge
->list
[UPPER
], &upper
->lower
);
1055 BUG_ON(!upper
->checked
);
1056 BUG_ON(cowonly
!= upper
->cowonly
);
1058 rb_node
= tree_insert(&cache
->rb_root
, upper
->bytenr
,
1061 backref_tree_panic(rb_node
, -EEXIST
,
1065 list_add_tail(&edge
->list
[UPPER
], &upper
->lower
);
1067 list_for_each_entry(edge
, &upper
->upper
, list
[LOWER
])
1068 list_add_tail(&edge
->list
[UPPER
], &list
);
1071 * process useless backref nodes. backref nodes for tree leaves
1072 * are deleted from the cache. backref nodes for upper level
1073 * tree blocks are left in the cache to avoid unnecessary backref
1076 while (!list_empty(&useless
)) {
1077 upper
= list_entry(useless
.next
, struct backref_node
, list
);
1078 list_del_init(&upper
->list
);
1079 BUG_ON(!list_empty(&upper
->upper
));
1082 if (upper
->lowest
) {
1083 list_del_init(&upper
->lower
);
1086 while (!list_empty(&upper
->lower
)) {
1087 edge
= list_entry(upper
->lower
.next
,
1088 struct backref_edge
, list
[UPPER
]);
1089 list_del(&edge
->list
[UPPER
]);
1090 list_del(&edge
->list
[LOWER
]);
1091 lower
= edge
->node
[LOWER
];
1092 free_backref_edge(cache
, edge
);
1094 if (list_empty(&lower
->upper
))
1095 list_add(&lower
->list
, &useless
);
1097 __mark_block_processed(rc
, upper
);
1098 if (upper
->level
> 0) {
1099 list_add(&upper
->list
, &cache
->detached
);
1100 upper
->detached
= 1;
1102 rb_erase(&upper
->rb_node
, &cache
->rb_root
);
1103 free_backref_node(cache
, upper
);
1107 btrfs_free_path(path1
);
1108 btrfs_free_path(path2
);
1110 while (!list_empty(&useless
)) {
1111 lower
= list_entry(useless
.next
,
1112 struct backref_node
, upper
);
1113 list_del_init(&lower
->upper
);
1116 INIT_LIST_HEAD(&list
);
1118 if (RB_EMPTY_NODE(&upper
->rb_node
)) {
1119 list_splice_tail(&upper
->upper
, &list
);
1120 free_backref_node(cache
, upper
);
1123 if (list_empty(&list
))
1126 edge
= list_entry(list
.next
, struct backref_edge
,
1128 list_del(&edge
->list
[LOWER
]);
1129 upper
= edge
->node
[UPPER
];
1130 free_backref_edge(cache
, edge
);
1132 return ERR_PTR(err
);
1134 BUG_ON(node
&& node
->detached
);
1139 * helper to add backref node for the newly created snapshot.
1140 * the backref node is created by cloning backref node that
1141 * corresponds to root of source tree
1143 static int clone_backref_node(struct btrfs_trans_handle
*trans
,
1144 struct reloc_control
*rc
,
1145 struct btrfs_root
*src
,
1146 struct btrfs_root
*dest
)
1148 struct btrfs_root
*reloc_root
= src
->reloc_root
;
1149 struct backref_cache
*cache
= &rc
->backref_cache
;
1150 struct backref_node
*node
= NULL
;
1151 struct backref_node
*new_node
;
1152 struct backref_edge
*edge
;
1153 struct backref_edge
*new_edge
;
1154 struct rb_node
*rb_node
;
1156 if (cache
->last_trans
> 0)
1157 update_backref_cache(trans
, cache
);
1159 rb_node
= tree_search(&cache
->rb_root
, src
->commit_root
->start
);
1161 node
= rb_entry(rb_node
, struct backref_node
, rb_node
);
1165 BUG_ON(node
->new_bytenr
!= reloc_root
->node
->start
);
1169 rb_node
= tree_search(&cache
->rb_root
,
1170 reloc_root
->commit_root
->start
);
1172 node
= rb_entry(rb_node
, struct backref_node
,
1174 BUG_ON(node
->detached
);
1181 new_node
= alloc_backref_node(cache
);
1185 new_node
->bytenr
= dest
->node
->start
;
1186 new_node
->level
= node
->level
;
1187 new_node
->lowest
= node
->lowest
;
1188 new_node
->checked
= 1;
1189 new_node
->root
= dest
;
1191 if (!node
->lowest
) {
1192 list_for_each_entry(edge
, &node
->lower
, list
[UPPER
]) {
1193 new_edge
= alloc_backref_edge(cache
);
1197 new_edge
->node
[UPPER
] = new_node
;
1198 new_edge
->node
[LOWER
] = edge
->node
[LOWER
];
1199 list_add_tail(&new_edge
->list
[UPPER
],
1203 list_add_tail(&new_node
->lower
, &cache
->leaves
);
1206 rb_node
= tree_insert(&cache
->rb_root
, new_node
->bytenr
,
1207 &new_node
->rb_node
);
1209 backref_tree_panic(rb_node
, -EEXIST
, new_node
->bytenr
);
1211 if (!new_node
->lowest
) {
1212 list_for_each_entry(new_edge
, &new_node
->lower
, list
[UPPER
]) {
1213 list_add_tail(&new_edge
->list
[LOWER
],
1214 &new_edge
->node
[LOWER
]->upper
);
1219 while (!list_empty(&new_node
->lower
)) {
1220 new_edge
= list_entry(new_node
->lower
.next
,
1221 struct backref_edge
, list
[UPPER
]);
1222 list_del(&new_edge
->list
[UPPER
]);
1223 free_backref_edge(cache
, new_edge
);
1225 free_backref_node(cache
, new_node
);
1230 * helper to add 'address of tree root -> reloc tree' mapping
1232 static int __must_check
__add_reloc_root(struct btrfs_root
*root
)
1234 struct rb_node
*rb_node
;
1235 struct mapping_node
*node
;
1236 struct reloc_control
*rc
= root
->fs_info
->reloc_ctl
;
1238 node
= kmalloc(sizeof(*node
), GFP_NOFS
);
1242 node
->bytenr
= root
->node
->start
;
1245 spin_lock(&rc
->reloc_root_tree
.lock
);
1246 rb_node
= tree_insert(&rc
->reloc_root_tree
.rb_root
,
1247 node
->bytenr
, &node
->rb_node
);
1248 spin_unlock(&rc
->reloc_root_tree
.lock
);
1250 btrfs_panic(root
->fs_info
, -EEXIST
, "Duplicate root found "
1251 "for start=%llu while inserting into relocation "
1252 "tree\n", node
->bytenr
);
1257 list_add_tail(&root
->root_list
, &rc
->reloc_roots
);
1262 * helper to update/delete the 'address of tree root -> reloc tree'
1265 static int __update_reloc_root(struct btrfs_root
*root
, int del
)
1267 struct rb_node
*rb_node
;
1268 struct mapping_node
*node
= NULL
;
1269 struct reloc_control
*rc
= root
->fs_info
->reloc_ctl
;
1271 spin_lock(&rc
->reloc_root_tree
.lock
);
1272 rb_node
= tree_search(&rc
->reloc_root_tree
.rb_root
,
1273 root
->commit_root
->start
);
1275 node
= rb_entry(rb_node
, struct mapping_node
, rb_node
);
1276 rb_erase(&node
->rb_node
, &rc
->reloc_root_tree
.rb_root
);
1278 spin_unlock(&rc
->reloc_root_tree
.lock
);
1282 BUG_ON((struct btrfs_root
*)node
->data
!= root
);
1285 spin_lock(&rc
->reloc_root_tree
.lock
);
1286 node
->bytenr
= root
->node
->start
;
1287 rb_node
= tree_insert(&rc
->reloc_root_tree
.rb_root
,
1288 node
->bytenr
, &node
->rb_node
);
1289 spin_unlock(&rc
->reloc_root_tree
.lock
);
1291 backref_tree_panic(rb_node
, -EEXIST
, node
->bytenr
);
1293 spin_lock(&root
->fs_info
->trans_lock
);
1294 list_del_init(&root
->root_list
);
1295 spin_unlock(&root
->fs_info
->trans_lock
);
1301 static struct btrfs_root
*create_reloc_root(struct btrfs_trans_handle
*trans
,
1302 struct btrfs_root
*root
, u64 objectid
)
1304 struct btrfs_root
*reloc_root
;
1305 struct extent_buffer
*eb
;
1306 struct btrfs_root_item
*root_item
;
1307 struct btrfs_key root_key
;
1310 root_item
= kmalloc(sizeof(*root_item
), GFP_NOFS
);
1313 root_key
.objectid
= BTRFS_TREE_RELOC_OBJECTID
;
1314 root_key
.type
= BTRFS_ROOT_ITEM_KEY
;
1315 root_key
.offset
= objectid
;
1317 if (root
->root_key
.objectid
== objectid
) {
1318 /* called by btrfs_init_reloc_root */
1319 ret
= btrfs_copy_root(trans
, root
, root
->commit_root
, &eb
,
1320 BTRFS_TREE_RELOC_OBJECTID
);
1323 btrfs_set_root_last_snapshot(&root
->root_item
,
1324 trans
->transid
- 1);
1327 * called by btrfs_reloc_post_snapshot_hook.
1328 * the source tree is a reloc tree, all tree blocks
1329 * modified after it was created have RELOC flag
1330 * set in their headers. so it's OK to not update
1331 * the 'last_snapshot'.
1333 ret
= btrfs_copy_root(trans
, root
, root
->node
, &eb
,
1334 BTRFS_TREE_RELOC_OBJECTID
);
1338 memcpy(root_item
, &root
->root_item
, sizeof(*root_item
));
1339 btrfs_set_root_bytenr(root_item
, eb
->start
);
1340 btrfs_set_root_level(root_item
, btrfs_header_level(eb
));
1341 btrfs_set_root_generation(root_item
, trans
->transid
);
1343 if (root
->root_key
.objectid
== objectid
) {
1344 btrfs_set_root_refs(root_item
, 0);
1345 memset(&root_item
->drop_progress
, 0,
1346 sizeof(struct btrfs_disk_key
));
1347 root_item
->drop_level
= 0;
1350 btrfs_tree_unlock(eb
);
1351 free_extent_buffer(eb
);
1353 ret
= btrfs_insert_root(trans
, root
->fs_info
->tree_root
,
1354 &root_key
, root_item
);
1358 reloc_root
= btrfs_read_fs_root_no_radix(root
->fs_info
->tree_root
,
1360 BUG_ON(IS_ERR(reloc_root
));
1361 reloc_root
->last_trans
= trans
->transid
;
1366 * create reloc tree for a given fs tree. reloc tree is just a
1367 * snapshot of the fs tree with special root objectid.
1369 int btrfs_init_reloc_root(struct btrfs_trans_handle
*trans
,
1370 struct btrfs_root
*root
)
1372 struct btrfs_root
*reloc_root
;
1373 struct reloc_control
*rc
= root
->fs_info
->reloc_ctl
;
1377 if (root
->reloc_root
) {
1378 reloc_root
= root
->reloc_root
;
1379 reloc_root
->last_trans
= trans
->transid
;
1383 if (!rc
|| !rc
->create_reloc_tree
||
1384 root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
)
1387 if (!trans
->block_rsv
) {
1388 trans
->block_rsv
= rc
->block_rsv
;
1391 reloc_root
= create_reloc_root(trans
, root
, root
->root_key
.objectid
);
1393 trans
->block_rsv
= NULL
;
1395 ret
= __add_reloc_root(reloc_root
);
1397 root
->reloc_root
= reloc_root
;
1402 * update root item of reloc tree
1404 int btrfs_update_reloc_root(struct btrfs_trans_handle
*trans
,
1405 struct btrfs_root
*root
)
1407 struct btrfs_root
*reloc_root
;
1408 struct btrfs_root_item
*root_item
;
1412 if (!root
->reloc_root
)
1415 reloc_root
= root
->reloc_root
;
1416 root_item
= &reloc_root
->root_item
;
1418 if (root
->fs_info
->reloc_ctl
->merge_reloc_tree
&&
1419 btrfs_root_refs(root_item
) == 0) {
1420 root
->reloc_root
= NULL
;
1424 __update_reloc_root(reloc_root
, del
);
1426 if (reloc_root
->commit_root
!= reloc_root
->node
) {
1427 btrfs_set_root_node(root_item
, reloc_root
->node
);
1428 free_extent_buffer(reloc_root
->commit_root
);
1429 reloc_root
->commit_root
= btrfs_root_node(reloc_root
);
1432 ret
= btrfs_update_root(trans
, root
->fs_info
->tree_root
,
1433 &reloc_root
->root_key
, root_item
);
1441 * helper to find first cached inode with inode number >= objectid
1444 static struct inode
*find_next_inode(struct btrfs_root
*root
, u64 objectid
)
1446 struct rb_node
*node
;
1447 struct rb_node
*prev
;
1448 struct btrfs_inode
*entry
;
1449 struct inode
*inode
;
1451 spin_lock(&root
->inode_lock
);
1453 node
= root
->inode_tree
.rb_node
;
1457 entry
= rb_entry(node
, struct btrfs_inode
, rb_node
);
1459 if (objectid
< btrfs_ino(&entry
->vfs_inode
))
1460 node
= node
->rb_left
;
1461 else if (objectid
> btrfs_ino(&entry
->vfs_inode
))
1462 node
= node
->rb_right
;
1468 entry
= rb_entry(prev
, struct btrfs_inode
, rb_node
);
1469 if (objectid
<= btrfs_ino(&entry
->vfs_inode
)) {
1473 prev
= rb_next(prev
);
1477 entry
= rb_entry(node
, struct btrfs_inode
, rb_node
);
1478 inode
= igrab(&entry
->vfs_inode
);
1480 spin_unlock(&root
->inode_lock
);
1484 objectid
= btrfs_ino(&entry
->vfs_inode
) + 1;
1485 if (cond_resched_lock(&root
->inode_lock
))
1488 node
= rb_next(node
);
1490 spin_unlock(&root
->inode_lock
);
1494 static int in_block_group(u64 bytenr
,
1495 struct btrfs_block_group_cache
*block_group
)
1497 if (bytenr
>= block_group
->key
.objectid
&&
1498 bytenr
< block_group
->key
.objectid
+ block_group
->key
.offset
)
1504 * get new location of data
1506 static int get_new_location(struct inode
*reloc_inode
, u64
*new_bytenr
,
1507 u64 bytenr
, u64 num_bytes
)
1509 struct btrfs_root
*root
= BTRFS_I(reloc_inode
)->root
;
1510 struct btrfs_path
*path
;
1511 struct btrfs_file_extent_item
*fi
;
1512 struct extent_buffer
*leaf
;
1515 path
= btrfs_alloc_path();
1519 bytenr
-= BTRFS_I(reloc_inode
)->index_cnt
;
1520 ret
= btrfs_lookup_file_extent(NULL
, root
, path
, btrfs_ino(reloc_inode
),
1529 leaf
= path
->nodes
[0];
1530 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1531 struct btrfs_file_extent_item
);
1533 BUG_ON(btrfs_file_extent_offset(leaf
, fi
) ||
1534 btrfs_file_extent_compression(leaf
, fi
) ||
1535 btrfs_file_extent_encryption(leaf
, fi
) ||
1536 btrfs_file_extent_other_encoding(leaf
, fi
));
1538 if (num_bytes
!= btrfs_file_extent_disk_num_bytes(leaf
, fi
)) {
1543 *new_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1546 btrfs_free_path(path
);
1551 * update file extent items in the tree leaf to point to
1552 * the new locations.
1554 static noinline_for_stack
1555 int replace_file_extents(struct btrfs_trans_handle
*trans
,
1556 struct reloc_control
*rc
,
1557 struct btrfs_root
*root
,
1558 struct extent_buffer
*leaf
)
1560 struct btrfs_key key
;
1561 struct btrfs_file_extent_item
*fi
;
1562 struct inode
*inode
= NULL
;
1574 if (rc
->stage
!= UPDATE_DATA_PTRS
)
1577 /* reloc trees always use full backref */
1578 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
)
1579 parent
= leaf
->start
;
1583 nritems
= btrfs_header_nritems(leaf
);
1584 for (i
= 0; i
< nritems
; i
++) {
1586 btrfs_item_key_to_cpu(leaf
, &key
, i
);
1587 if (key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1589 fi
= btrfs_item_ptr(leaf
, i
, struct btrfs_file_extent_item
);
1590 if (btrfs_file_extent_type(leaf
, fi
) ==
1591 BTRFS_FILE_EXTENT_INLINE
)
1593 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1594 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1597 if (!in_block_group(bytenr
, rc
->block_group
))
1601 * if we are modifying block in fs tree, wait for readpage
1602 * to complete and drop the extent cache
1604 if (root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
) {
1606 inode
= find_next_inode(root
, key
.objectid
);
1608 } else if (inode
&& btrfs_ino(inode
) < key
.objectid
) {
1609 btrfs_add_delayed_iput(inode
);
1610 inode
= find_next_inode(root
, key
.objectid
);
1612 if (inode
&& btrfs_ino(inode
) == key
.objectid
) {
1614 btrfs_file_extent_num_bytes(leaf
, fi
);
1615 WARN_ON(!IS_ALIGNED(key
.offset
,
1617 WARN_ON(!IS_ALIGNED(end
, root
->sectorsize
));
1619 ret
= try_lock_extent(&BTRFS_I(inode
)->io_tree
,
1624 btrfs_drop_extent_cache(inode
, key
.offset
, end
,
1626 unlock_extent(&BTRFS_I(inode
)->io_tree
,
1631 ret
= get_new_location(rc
->data_inode
, &new_bytenr
,
1639 btrfs_set_file_extent_disk_bytenr(leaf
, fi
, new_bytenr
);
1642 key
.offset
-= btrfs_file_extent_offset(leaf
, fi
);
1643 ret
= btrfs_inc_extent_ref(trans
, root
, new_bytenr
,
1645 btrfs_header_owner(leaf
),
1646 key
.objectid
, key
.offset
, 1);
1649 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1650 parent
, btrfs_header_owner(leaf
),
1651 key
.objectid
, key
.offset
, 1);
1655 btrfs_mark_buffer_dirty(leaf
);
1657 btrfs_add_delayed_iput(inode
);
1661 static noinline_for_stack
1662 int memcmp_node_keys(struct extent_buffer
*eb
, int slot
,
1663 struct btrfs_path
*path
, int level
)
1665 struct btrfs_disk_key key1
;
1666 struct btrfs_disk_key key2
;
1667 btrfs_node_key(eb
, &key1
, slot
);
1668 btrfs_node_key(path
->nodes
[level
], &key2
, path
->slots
[level
]);
1669 return memcmp(&key1
, &key2
, sizeof(key1
));
1673 * try to replace tree blocks in fs tree with the new blocks
1674 * in reloc tree. tree blocks haven't been modified since the
1675 * reloc tree was create can be replaced.
1677 * if a block was replaced, level of the block + 1 is returned.
1678 * if no block got replaced, 0 is returned. if there are other
1679 * errors, a negative error number is returned.
1681 static noinline_for_stack
1682 int replace_path(struct btrfs_trans_handle
*trans
,
1683 struct btrfs_root
*dest
, struct btrfs_root
*src
,
1684 struct btrfs_path
*path
, struct btrfs_key
*next_key
,
1685 int lowest_level
, int max_level
)
1687 struct extent_buffer
*eb
;
1688 struct extent_buffer
*parent
;
1689 struct btrfs_key key
;
1701 BUG_ON(src
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
);
1702 BUG_ON(dest
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
);
1704 last_snapshot
= btrfs_root_last_snapshot(&src
->root_item
);
1706 slot
= path
->slots
[lowest_level
];
1707 btrfs_node_key_to_cpu(path
->nodes
[lowest_level
], &key
, slot
);
1709 eb
= btrfs_lock_root_node(dest
);
1710 btrfs_set_lock_blocking(eb
);
1711 level
= btrfs_header_level(eb
);
1713 if (level
< lowest_level
) {
1714 btrfs_tree_unlock(eb
);
1715 free_extent_buffer(eb
);
1720 ret
= btrfs_cow_block(trans
, dest
, eb
, NULL
, 0, &eb
);
1723 btrfs_set_lock_blocking(eb
);
1726 next_key
->objectid
= (u64
)-1;
1727 next_key
->type
= (u8
)-1;
1728 next_key
->offset
= (u64
)-1;
1733 level
= btrfs_header_level(parent
);
1734 BUG_ON(level
< lowest_level
);
1736 ret
= btrfs_bin_search(parent
, &key
, level
, &slot
);
1737 if (ret
&& slot
> 0)
1740 if (next_key
&& slot
+ 1 < btrfs_header_nritems(parent
))
1741 btrfs_node_key_to_cpu(parent
, next_key
, slot
+ 1);
1743 old_bytenr
= btrfs_node_blockptr(parent
, slot
);
1744 blocksize
= btrfs_level_size(dest
, level
- 1);
1745 old_ptr_gen
= btrfs_node_ptr_generation(parent
, slot
);
1747 if (level
<= max_level
) {
1748 eb
= path
->nodes
[level
];
1749 new_bytenr
= btrfs_node_blockptr(eb
,
1750 path
->slots
[level
]);
1751 new_ptr_gen
= btrfs_node_ptr_generation(eb
,
1752 path
->slots
[level
]);
1758 if (new_bytenr
> 0 && new_bytenr
== old_bytenr
) {
1764 if (new_bytenr
== 0 || old_ptr_gen
> last_snapshot
||
1765 memcmp_node_keys(parent
, slot
, path
, level
)) {
1766 if (level
<= lowest_level
) {
1771 eb
= read_tree_block(dest
, old_bytenr
, blocksize
,
1773 if (!eb
|| !extent_buffer_uptodate(eb
)) {
1774 ret
= (!eb
) ? -ENOMEM
: -EIO
;
1775 free_extent_buffer(eb
);
1778 btrfs_tree_lock(eb
);
1780 ret
= btrfs_cow_block(trans
, dest
, eb
, parent
,
1784 btrfs_set_lock_blocking(eb
);
1786 btrfs_tree_unlock(parent
);
1787 free_extent_buffer(parent
);
1794 btrfs_tree_unlock(parent
);
1795 free_extent_buffer(parent
);
1800 btrfs_node_key_to_cpu(path
->nodes
[level
], &key
,
1801 path
->slots
[level
]);
1802 btrfs_release_path(path
);
1804 path
->lowest_level
= level
;
1805 ret
= btrfs_search_slot(trans
, src
, &key
, path
, 0, 1);
1806 path
->lowest_level
= 0;
1810 * swap blocks in fs tree and reloc tree.
1812 btrfs_set_node_blockptr(parent
, slot
, new_bytenr
);
1813 btrfs_set_node_ptr_generation(parent
, slot
, new_ptr_gen
);
1814 btrfs_mark_buffer_dirty(parent
);
1816 btrfs_set_node_blockptr(path
->nodes
[level
],
1817 path
->slots
[level
], old_bytenr
);
1818 btrfs_set_node_ptr_generation(path
->nodes
[level
],
1819 path
->slots
[level
], old_ptr_gen
);
1820 btrfs_mark_buffer_dirty(path
->nodes
[level
]);
1822 ret
= btrfs_inc_extent_ref(trans
, src
, old_bytenr
, blocksize
,
1823 path
->nodes
[level
]->start
,
1824 src
->root_key
.objectid
, level
- 1, 0,
1827 ret
= btrfs_inc_extent_ref(trans
, dest
, new_bytenr
, blocksize
,
1828 0, dest
->root_key
.objectid
, level
- 1,
1832 ret
= btrfs_free_extent(trans
, src
, new_bytenr
, blocksize
,
1833 path
->nodes
[level
]->start
,
1834 src
->root_key
.objectid
, level
- 1, 0,
1838 ret
= btrfs_free_extent(trans
, dest
, old_bytenr
, blocksize
,
1839 0, dest
->root_key
.objectid
, level
- 1,
1843 btrfs_unlock_up_safe(path
, 0);
1848 btrfs_tree_unlock(parent
);
1849 free_extent_buffer(parent
);
1854 * helper to find next relocated block in reloc tree
1856 static noinline_for_stack
1857 int walk_up_reloc_tree(struct btrfs_root
*root
, struct btrfs_path
*path
,
1860 struct extent_buffer
*eb
;
1865 last_snapshot
= btrfs_root_last_snapshot(&root
->root_item
);
1867 for (i
= 0; i
< *level
; i
++) {
1868 free_extent_buffer(path
->nodes
[i
]);
1869 path
->nodes
[i
] = NULL
;
1872 for (i
= *level
; i
< BTRFS_MAX_LEVEL
&& path
->nodes
[i
]; i
++) {
1873 eb
= path
->nodes
[i
];
1874 nritems
= btrfs_header_nritems(eb
);
1875 while (path
->slots
[i
] + 1 < nritems
) {
1877 if (btrfs_node_ptr_generation(eb
, path
->slots
[i
]) <=
1884 free_extent_buffer(path
->nodes
[i
]);
1885 path
->nodes
[i
] = NULL
;
1891 * walk down reloc tree to find relocated block of lowest level
1893 static noinline_for_stack
1894 int walk_down_reloc_tree(struct btrfs_root
*root
, struct btrfs_path
*path
,
1897 struct extent_buffer
*eb
= NULL
;
1905 last_snapshot
= btrfs_root_last_snapshot(&root
->root_item
);
1907 for (i
= *level
; i
> 0; i
--) {
1908 eb
= path
->nodes
[i
];
1909 nritems
= btrfs_header_nritems(eb
);
1910 while (path
->slots
[i
] < nritems
) {
1911 ptr_gen
= btrfs_node_ptr_generation(eb
, path
->slots
[i
]);
1912 if (ptr_gen
> last_snapshot
)
1916 if (path
->slots
[i
] >= nritems
) {
1927 bytenr
= btrfs_node_blockptr(eb
, path
->slots
[i
]);
1928 blocksize
= btrfs_level_size(root
, i
- 1);
1929 eb
= read_tree_block(root
, bytenr
, blocksize
, ptr_gen
);
1930 if (!eb
|| !extent_buffer_uptodate(eb
)) {
1931 free_extent_buffer(eb
);
1934 BUG_ON(btrfs_header_level(eb
) != i
- 1);
1935 path
->nodes
[i
- 1] = eb
;
1936 path
->slots
[i
- 1] = 0;
1942 * invalidate extent cache for file extents whose key in range of
1943 * [min_key, max_key)
1945 static int invalidate_extent_cache(struct btrfs_root
*root
,
1946 struct btrfs_key
*min_key
,
1947 struct btrfs_key
*max_key
)
1949 struct inode
*inode
= NULL
;
1954 objectid
= min_key
->objectid
;
1959 if (objectid
> max_key
->objectid
)
1962 inode
= find_next_inode(root
, objectid
);
1965 ino
= btrfs_ino(inode
);
1967 if (ino
> max_key
->objectid
) {
1973 if (!S_ISREG(inode
->i_mode
))
1976 if (unlikely(min_key
->objectid
== ino
)) {
1977 if (min_key
->type
> BTRFS_EXTENT_DATA_KEY
)
1979 if (min_key
->type
< BTRFS_EXTENT_DATA_KEY
)
1982 start
= min_key
->offset
;
1983 WARN_ON(!IS_ALIGNED(start
, root
->sectorsize
));
1989 if (unlikely(max_key
->objectid
== ino
)) {
1990 if (max_key
->type
< BTRFS_EXTENT_DATA_KEY
)
1992 if (max_key
->type
> BTRFS_EXTENT_DATA_KEY
) {
1995 if (max_key
->offset
== 0)
1997 end
= max_key
->offset
;
1998 WARN_ON(!IS_ALIGNED(end
, root
->sectorsize
));
2005 /* the lock_extent waits for readpage to complete */
2006 lock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
2007 btrfs_drop_extent_cache(inode
, start
, end
, 1);
2008 unlock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
2013 static int find_next_key(struct btrfs_path
*path
, int level
,
2014 struct btrfs_key
*key
)
2017 while (level
< BTRFS_MAX_LEVEL
) {
2018 if (!path
->nodes
[level
])
2020 if (path
->slots
[level
] + 1 <
2021 btrfs_header_nritems(path
->nodes
[level
])) {
2022 btrfs_node_key_to_cpu(path
->nodes
[level
], key
,
2023 path
->slots
[level
] + 1);
2032 * merge the relocated tree blocks in reloc tree with corresponding
2035 static noinline_for_stack
int merge_reloc_root(struct reloc_control
*rc
,
2036 struct btrfs_root
*root
)
2038 LIST_HEAD(inode_list
);
2039 struct btrfs_key key
;
2040 struct btrfs_key next_key
;
2041 struct btrfs_trans_handle
*trans
;
2042 struct btrfs_root
*reloc_root
;
2043 struct btrfs_root_item
*root_item
;
2044 struct btrfs_path
*path
;
2045 struct extent_buffer
*leaf
;
2053 path
= btrfs_alloc_path();
2058 reloc_root
= root
->reloc_root
;
2059 root_item
= &reloc_root
->root_item
;
2061 if (btrfs_disk_key_objectid(&root_item
->drop_progress
) == 0) {
2062 level
= btrfs_root_level(root_item
);
2063 extent_buffer_get(reloc_root
->node
);
2064 path
->nodes
[level
] = reloc_root
->node
;
2065 path
->slots
[level
] = 0;
2067 btrfs_disk_key_to_cpu(&key
, &root_item
->drop_progress
);
2069 level
= root_item
->drop_level
;
2071 path
->lowest_level
= level
;
2072 ret
= btrfs_search_slot(NULL
, reloc_root
, &key
, path
, 0, 0);
2073 path
->lowest_level
= 0;
2075 btrfs_free_path(path
);
2079 btrfs_node_key_to_cpu(path
->nodes
[level
], &next_key
,
2080 path
->slots
[level
]);
2081 WARN_ON(memcmp(&key
, &next_key
, sizeof(key
)));
2083 btrfs_unlock_up_safe(path
, 0);
2086 min_reserved
= root
->nodesize
* (BTRFS_MAX_LEVEL
- 1) * 2;
2087 memset(&next_key
, 0, sizeof(next_key
));
2090 trans
= btrfs_start_transaction(root
, 0);
2091 BUG_ON(IS_ERR(trans
));
2092 trans
->block_rsv
= rc
->block_rsv
;
2094 ret
= btrfs_block_rsv_refill(root
, rc
->block_rsv
, min_reserved
,
2095 BTRFS_RESERVE_FLUSH_ALL
);
2097 BUG_ON(ret
!= -EAGAIN
);
2098 ret
= btrfs_commit_transaction(trans
, root
);
2106 ret
= walk_down_reloc_tree(reloc_root
, path
, &level
);
2114 if (!find_next_key(path
, level
, &key
) &&
2115 btrfs_comp_cpu_keys(&next_key
, &key
) >= 0) {
2118 ret
= replace_path(trans
, root
, reloc_root
, path
,
2119 &next_key
, level
, max_level
);
2128 btrfs_node_key_to_cpu(path
->nodes
[level
], &key
,
2129 path
->slots
[level
]);
2133 ret
= walk_up_reloc_tree(reloc_root
, path
, &level
);
2139 * save the merging progress in the drop_progress.
2140 * this is OK since root refs == 1 in this case.
2142 btrfs_node_key(path
->nodes
[level
], &root_item
->drop_progress
,
2143 path
->slots
[level
]);
2144 root_item
->drop_level
= level
;
2146 btrfs_end_transaction_throttle(trans
, root
);
2148 btrfs_btree_balance_dirty(root
);
2150 if (replaced
&& rc
->stage
== UPDATE_DATA_PTRS
)
2151 invalidate_extent_cache(root
, &key
, &next_key
);
2155 * handle the case only one block in the fs tree need to be
2156 * relocated and the block is tree root.
2158 leaf
= btrfs_lock_root_node(root
);
2159 ret
= btrfs_cow_block(trans
, root
, leaf
, NULL
, 0, &leaf
);
2160 btrfs_tree_unlock(leaf
);
2161 free_extent_buffer(leaf
);
2165 btrfs_free_path(path
);
2168 memset(&root_item
->drop_progress
, 0,
2169 sizeof(root_item
->drop_progress
));
2170 root_item
->drop_level
= 0;
2171 btrfs_set_root_refs(root_item
, 0);
2172 btrfs_update_reloc_root(trans
, root
);
2175 btrfs_end_transaction_throttle(trans
, root
);
2177 btrfs_btree_balance_dirty(root
);
2179 if (replaced
&& rc
->stage
== UPDATE_DATA_PTRS
)
2180 invalidate_extent_cache(root
, &key
, &next_key
);
2185 static noinline_for_stack
2186 int prepare_to_merge(struct reloc_control
*rc
, int err
)
2188 struct btrfs_root
*root
= rc
->extent_root
;
2189 struct btrfs_root
*reloc_root
;
2190 struct btrfs_trans_handle
*trans
;
2191 LIST_HEAD(reloc_roots
);
2195 mutex_lock(&root
->fs_info
->reloc_mutex
);
2196 rc
->merging_rsv_size
+= root
->nodesize
* (BTRFS_MAX_LEVEL
- 1) * 2;
2197 rc
->merging_rsv_size
+= rc
->nodes_relocated
* 2;
2198 mutex_unlock(&root
->fs_info
->reloc_mutex
);
2202 num_bytes
= rc
->merging_rsv_size
;
2203 ret
= btrfs_block_rsv_add(root
, rc
->block_rsv
, num_bytes
,
2204 BTRFS_RESERVE_FLUSH_ALL
);
2209 trans
= btrfs_join_transaction(rc
->extent_root
);
2210 if (IS_ERR(trans
)) {
2212 btrfs_block_rsv_release(rc
->extent_root
,
2213 rc
->block_rsv
, num_bytes
);
2214 return PTR_ERR(trans
);
2218 if (num_bytes
!= rc
->merging_rsv_size
) {
2219 btrfs_end_transaction(trans
, rc
->extent_root
);
2220 btrfs_block_rsv_release(rc
->extent_root
,
2221 rc
->block_rsv
, num_bytes
);
2226 rc
->merge_reloc_tree
= 1;
2228 while (!list_empty(&rc
->reloc_roots
)) {
2229 reloc_root
= list_entry(rc
->reloc_roots
.next
,
2230 struct btrfs_root
, root_list
);
2231 list_del_init(&reloc_root
->root_list
);
2233 root
= read_fs_root(reloc_root
->fs_info
,
2234 reloc_root
->root_key
.offset
);
2235 BUG_ON(IS_ERR(root
));
2236 BUG_ON(root
->reloc_root
!= reloc_root
);
2239 * set reference count to 1, so btrfs_recover_relocation
2240 * knows it should resumes merging
2243 btrfs_set_root_refs(&reloc_root
->root_item
, 1);
2244 btrfs_update_reloc_root(trans
, root
);
2246 list_add(&reloc_root
->root_list
, &reloc_roots
);
2249 list_splice(&reloc_roots
, &rc
->reloc_roots
);
2252 btrfs_commit_transaction(trans
, rc
->extent_root
);
2254 btrfs_end_transaction(trans
, rc
->extent_root
);
2258 static noinline_for_stack
2259 void free_reloc_roots(struct list_head
*list
)
2261 struct btrfs_root
*reloc_root
;
2263 while (!list_empty(list
)) {
2264 reloc_root
= list_entry(list
->next
, struct btrfs_root
,
2266 __update_reloc_root(reloc_root
, 1);
2267 free_extent_buffer(reloc_root
->node
);
2268 free_extent_buffer(reloc_root
->commit_root
);
2273 static noinline_for_stack
2274 int merge_reloc_roots(struct reloc_control
*rc
)
2276 struct btrfs_root
*root
;
2277 struct btrfs_root
*reloc_root
;
2278 LIST_HEAD(reloc_roots
);
2282 root
= rc
->extent_root
;
2285 * this serializes us with btrfs_record_root_in_transaction,
2286 * we have to make sure nobody is in the middle of
2287 * adding their roots to the list while we are
2290 mutex_lock(&root
->fs_info
->reloc_mutex
);
2291 list_splice_init(&rc
->reloc_roots
, &reloc_roots
);
2292 mutex_unlock(&root
->fs_info
->reloc_mutex
);
2294 while (!list_empty(&reloc_roots
)) {
2296 reloc_root
= list_entry(reloc_roots
.next
,
2297 struct btrfs_root
, root_list
);
2299 if (btrfs_root_refs(&reloc_root
->root_item
) > 0) {
2300 root
= read_fs_root(reloc_root
->fs_info
,
2301 reloc_root
->root_key
.offset
);
2302 BUG_ON(IS_ERR(root
));
2303 BUG_ON(root
->reloc_root
!= reloc_root
);
2305 ret
= merge_reloc_root(rc
, root
);
2309 list_del_init(&reloc_root
->root_list
);
2311 ret
= btrfs_drop_snapshot(reloc_root
, rc
->block_rsv
, 0, 1);
2313 if (list_empty(&reloc_root
->root_list
))
2314 list_add_tail(&reloc_root
->root_list
,
2326 btrfs_std_error(root
->fs_info
, ret
);
2327 if (!list_empty(&reloc_roots
))
2328 free_reloc_roots(&reloc_roots
);
2331 BUG_ON(!RB_EMPTY_ROOT(&rc
->reloc_root_tree
.rb_root
));
2335 static void free_block_list(struct rb_root
*blocks
)
2337 struct tree_block
*block
;
2338 struct rb_node
*rb_node
;
2339 while ((rb_node
= rb_first(blocks
))) {
2340 block
= rb_entry(rb_node
, struct tree_block
, rb_node
);
2341 rb_erase(rb_node
, blocks
);
2346 static int record_reloc_root_in_trans(struct btrfs_trans_handle
*trans
,
2347 struct btrfs_root
*reloc_root
)
2349 struct btrfs_root
*root
;
2351 if (reloc_root
->last_trans
== trans
->transid
)
2354 root
= read_fs_root(reloc_root
->fs_info
, reloc_root
->root_key
.offset
);
2355 BUG_ON(IS_ERR(root
));
2356 BUG_ON(root
->reloc_root
!= reloc_root
);
2358 return btrfs_record_root_in_trans(trans
, root
);
2361 static noinline_for_stack
2362 struct btrfs_root
*select_reloc_root(struct btrfs_trans_handle
*trans
,
2363 struct reloc_control
*rc
,
2364 struct backref_node
*node
,
2365 struct backref_edge
*edges
[], int *nr
)
2367 struct backref_node
*next
;
2368 struct btrfs_root
*root
;
2374 next
= walk_up_backref(next
, edges
, &index
);
2377 BUG_ON(!root
->ref_cows
);
2379 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
) {
2380 record_reloc_root_in_trans(trans
, root
);
2384 btrfs_record_root_in_trans(trans
, root
);
2385 root
= root
->reloc_root
;
2387 if (next
->new_bytenr
!= root
->node
->start
) {
2388 BUG_ON(next
->new_bytenr
);
2389 BUG_ON(!list_empty(&next
->list
));
2390 next
->new_bytenr
= root
->node
->start
;
2392 list_add_tail(&next
->list
,
2393 &rc
->backref_cache
.changed
);
2394 __mark_block_processed(rc
, next
);
2400 next
= walk_down_backref(edges
, &index
);
2401 if (!next
|| next
->level
<= node
->level
)
2409 /* setup backref node path for btrfs_reloc_cow_block */
2411 rc
->backref_cache
.path
[next
->level
] = next
;
2414 next
= edges
[index
]->node
[UPPER
];
2420 * select a tree root for relocation. return NULL if the block
2421 * is reference counted. we should use do_relocation() in this
2422 * case. return a tree root pointer if the block isn't reference
2423 * counted. return -ENOENT if the block is root of reloc tree.
2425 static noinline_for_stack
2426 struct btrfs_root
*select_one_root(struct btrfs_trans_handle
*trans
,
2427 struct backref_node
*node
)
2429 struct backref_node
*next
;
2430 struct btrfs_root
*root
;
2431 struct btrfs_root
*fs_root
= NULL
;
2432 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2438 next
= walk_up_backref(next
, edges
, &index
);
2442 /* no other choice for non-references counted tree */
2443 if (!root
->ref_cows
)
2446 if (root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
)
2452 next
= walk_down_backref(edges
, &index
);
2453 if (!next
|| next
->level
<= node
->level
)
2458 return ERR_PTR(-ENOENT
);
2462 static noinline_for_stack
2463 u64
calcu_metadata_size(struct reloc_control
*rc
,
2464 struct backref_node
*node
, int reserve
)
2466 struct backref_node
*next
= node
;
2467 struct backref_edge
*edge
;
2468 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2472 BUG_ON(reserve
&& node
->processed
);
2477 if (next
->processed
&& (reserve
|| next
!= node
))
2480 num_bytes
+= btrfs_level_size(rc
->extent_root
,
2483 if (list_empty(&next
->upper
))
2486 edge
= list_entry(next
->upper
.next
,
2487 struct backref_edge
, list
[LOWER
]);
2488 edges
[index
++] = edge
;
2489 next
= edge
->node
[UPPER
];
2491 next
= walk_down_backref(edges
, &index
);
2496 static int reserve_metadata_space(struct btrfs_trans_handle
*trans
,
2497 struct reloc_control
*rc
,
2498 struct backref_node
*node
)
2500 struct btrfs_root
*root
= rc
->extent_root
;
2504 num_bytes
= calcu_metadata_size(rc
, node
, 1) * 2;
2506 trans
->block_rsv
= rc
->block_rsv
;
2507 ret
= btrfs_block_rsv_add(root
, rc
->block_rsv
, num_bytes
,
2508 BTRFS_RESERVE_FLUSH_ALL
);
2511 rc
->commit_transaction
= 1;
2518 static void release_metadata_space(struct reloc_control
*rc
,
2519 struct backref_node
*node
)
2521 u64 num_bytes
= calcu_metadata_size(rc
, node
, 0) * 2;
2522 btrfs_block_rsv_release(rc
->extent_root
, rc
->block_rsv
, num_bytes
);
2526 * relocate a block tree, and then update pointers in upper level
2527 * blocks that reference the block to point to the new location.
2529 * if called by link_to_upper, the block has already been relocated.
2530 * in that case this function just updates pointers.
2532 static int do_relocation(struct btrfs_trans_handle
*trans
,
2533 struct reloc_control
*rc
,
2534 struct backref_node
*node
,
2535 struct btrfs_key
*key
,
2536 struct btrfs_path
*path
, int lowest
)
2538 struct backref_node
*upper
;
2539 struct backref_edge
*edge
;
2540 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2541 struct btrfs_root
*root
;
2542 struct extent_buffer
*eb
;
2551 BUG_ON(lowest
&& node
->eb
);
2553 path
->lowest_level
= node
->level
+ 1;
2554 rc
->backref_cache
.path
[node
->level
] = node
;
2555 list_for_each_entry(edge
, &node
->upper
, list
[LOWER
]) {
2558 upper
= edge
->node
[UPPER
];
2559 root
= select_reloc_root(trans
, rc
, upper
, edges
, &nr
);
2562 if (upper
->eb
&& !upper
->locked
) {
2564 ret
= btrfs_bin_search(upper
->eb
, key
,
2565 upper
->level
, &slot
);
2567 bytenr
= btrfs_node_blockptr(upper
->eb
, slot
);
2568 if (node
->eb
->start
== bytenr
)
2571 drop_node_buffer(upper
);
2575 ret
= btrfs_search_slot(trans
, root
, key
, path
, 0, 1);
2583 upper
->eb
= path
->nodes
[upper
->level
];
2584 path
->nodes
[upper
->level
] = NULL
;
2586 BUG_ON(upper
->eb
!= path
->nodes
[upper
->level
]);
2590 path
->locks
[upper
->level
] = 0;
2592 slot
= path
->slots
[upper
->level
];
2593 btrfs_release_path(path
);
2595 ret
= btrfs_bin_search(upper
->eb
, key
, upper
->level
,
2600 bytenr
= btrfs_node_blockptr(upper
->eb
, slot
);
2602 BUG_ON(bytenr
!= node
->bytenr
);
2604 if (node
->eb
->start
== bytenr
)
2608 blocksize
= btrfs_level_size(root
, node
->level
);
2609 generation
= btrfs_node_ptr_generation(upper
->eb
, slot
);
2610 eb
= read_tree_block(root
, bytenr
, blocksize
, generation
);
2611 if (!eb
|| !extent_buffer_uptodate(eb
)) {
2612 free_extent_buffer(eb
);
2616 btrfs_tree_lock(eb
);
2617 btrfs_set_lock_blocking(eb
);
2620 ret
= btrfs_cow_block(trans
, root
, eb
, upper
->eb
,
2622 btrfs_tree_unlock(eb
);
2623 free_extent_buffer(eb
);
2628 BUG_ON(node
->eb
!= eb
);
2630 btrfs_set_node_blockptr(upper
->eb
, slot
,
2632 btrfs_set_node_ptr_generation(upper
->eb
, slot
,
2634 btrfs_mark_buffer_dirty(upper
->eb
);
2636 ret
= btrfs_inc_extent_ref(trans
, root
,
2637 node
->eb
->start
, blocksize
,
2639 btrfs_header_owner(upper
->eb
),
2643 ret
= btrfs_drop_subtree(trans
, root
, eb
, upper
->eb
);
2647 if (!upper
->pending
)
2648 drop_node_buffer(upper
);
2650 unlock_node_buffer(upper
);
2655 if (!err
&& node
->pending
) {
2656 drop_node_buffer(node
);
2657 list_move_tail(&node
->list
, &rc
->backref_cache
.changed
);
2661 path
->lowest_level
= 0;
2662 BUG_ON(err
== -ENOSPC
);
2666 static int link_to_upper(struct btrfs_trans_handle
*trans
,
2667 struct reloc_control
*rc
,
2668 struct backref_node
*node
,
2669 struct btrfs_path
*path
)
2671 struct btrfs_key key
;
2673 btrfs_node_key_to_cpu(node
->eb
, &key
, 0);
2674 return do_relocation(trans
, rc
, node
, &key
, path
, 0);
2677 static int finish_pending_nodes(struct btrfs_trans_handle
*trans
,
2678 struct reloc_control
*rc
,
2679 struct btrfs_path
*path
, int err
)
2682 struct backref_cache
*cache
= &rc
->backref_cache
;
2683 struct backref_node
*node
;
2687 for (level
= 0; level
< BTRFS_MAX_LEVEL
; level
++) {
2688 while (!list_empty(&cache
->pending
[level
])) {
2689 node
= list_entry(cache
->pending
[level
].next
,
2690 struct backref_node
, list
);
2691 list_move_tail(&node
->list
, &list
);
2692 BUG_ON(!node
->pending
);
2695 ret
= link_to_upper(trans
, rc
, node
, path
);
2700 list_splice_init(&list
, &cache
->pending
[level
]);
2705 static void mark_block_processed(struct reloc_control
*rc
,
2706 u64 bytenr
, u32 blocksize
)
2708 set_extent_bits(&rc
->processed_blocks
, bytenr
, bytenr
+ blocksize
- 1,
2709 EXTENT_DIRTY
, GFP_NOFS
);
2712 static void __mark_block_processed(struct reloc_control
*rc
,
2713 struct backref_node
*node
)
2716 if (node
->level
== 0 ||
2717 in_block_group(node
->bytenr
, rc
->block_group
)) {
2718 blocksize
= btrfs_level_size(rc
->extent_root
, node
->level
);
2719 mark_block_processed(rc
, node
->bytenr
, blocksize
);
2721 node
->processed
= 1;
2725 * mark a block and all blocks directly/indirectly reference the block
2728 static void update_processed_blocks(struct reloc_control
*rc
,
2729 struct backref_node
*node
)
2731 struct backref_node
*next
= node
;
2732 struct backref_edge
*edge
;
2733 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2739 if (next
->processed
)
2742 __mark_block_processed(rc
, next
);
2744 if (list_empty(&next
->upper
))
2747 edge
= list_entry(next
->upper
.next
,
2748 struct backref_edge
, list
[LOWER
]);
2749 edges
[index
++] = edge
;
2750 next
= edge
->node
[UPPER
];
2752 next
= walk_down_backref(edges
, &index
);
2756 static int tree_block_processed(u64 bytenr
, u32 blocksize
,
2757 struct reloc_control
*rc
)
2759 if (test_range_bit(&rc
->processed_blocks
, bytenr
,
2760 bytenr
+ blocksize
- 1, EXTENT_DIRTY
, 1, NULL
))
2765 static int get_tree_block_key(struct reloc_control
*rc
,
2766 struct tree_block
*block
)
2768 struct extent_buffer
*eb
;
2770 BUG_ON(block
->key_ready
);
2771 eb
= read_tree_block(rc
->extent_root
, block
->bytenr
,
2772 block
->key
.objectid
, block
->key
.offset
);
2773 if (!eb
|| !extent_buffer_uptodate(eb
)) {
2774 free_extent_buffer(eb
);
2777 WARN_ON(btrfs_header_level(eb
) != block
->level
);
2778 if (block
->level
== 0)
2779 btrfs_item_key_to_cpu(eb
, &block
->key
, 0);
2781 btrfs_node_key_to_cpu(eb
, &block
->key
, 0);
2782 free_extent_buffer(eb
);
2783 block
->key_ready
= 1;
2787 static int reada_tree_block(struct reloc_control
*rc
,
2788 struct tree_block
*block
)
2790 BUG_ON(block
->key_ready
);
2791 if (block
->key
.type
== BTRFS_METADATA_ITEM_KEY
)
2792 readahead_tree_block(rc
->extent_root
, block
->bytenr
,
2793 block
->key
.objectid
,
2794 rc
->extent_root
->leafsize
);
2796 readahead_tree_block(rc
->extent_root
, block
->bytenr
,
2797 block
->key
.objectid
, block
->key
.offset
);
2802 * helper function to relocate a tree block
2804 static int relocate_tree_block(struct btrfs_trans_handle
*trans
,
2805 struct reloc_control
*rc
,
2806 struct backref_node
*node
,
2807 struct btrfs_key
*key
,
2808 struct btrfs_path
*path
)
2810 struct btrfs_root
*root
;
2817 BUG_ON(node
->processed
);
2818 root
= select_one_root(trans
, node
);
2819 if (root
== ERR_PTR(-ENOENT
)) {
2820 update_processed_blocks(rc
, node
);
2824 if (!root
|| root
->ref_cows
) {
2825 ret
= reserve_metadata_space(trans
, rc
, node
);
2832 if (root
->ref_cows
) {
2833 BUG_ON(node
->new_bytenr
);
2834 BUG_ON(!list_empty(&node
->list
));
2835 btrfs_record_root_in_trans(trans
, root
);
2836 root
= root
->reloc_root
;
2837 node
->new_bytenr
= root
->node
->start
;
2839 list_add_tail(&node
->list
, &rc
->backref_cache
.changed
);
2841 path
->lowest_level
= node
->level
;
2842 ret
= btrfs_search_slot(trans
, root
, key
, path
, 0, 1);
2843 btrfs_release_path(path
);
2848 update_processed_blocks(rc
, node
);
2850 ret
= do_relocation(trans
, rc
, node
, key
, path
, 1);
2853 if (ret
|| node
->level
== 0 || node
->cowonly
) {
2855 release_metadata_space(rc
, node
);
2856 remove_backref_node(&rc
->backref_cache
, node
);
2862 * relocate a list of blocks
2864 static noinline_for_stack
2865 int relocate_tree_blocks(struct btrfs_trans_handle
*trans
,
2866 struct reloc_control
*rc
, struct rb_root
*blocks
)
2868 struct backref_node
*node
;
2869 struct btrfs_path
*path
;
2870 struct tree_block
*block
;
2871 struct rb_node
*rb_node
;
2875 path
= btrfs_alloc_path();
2878 goto out_free_blocks
;
2881 rb_node
= rb_first(blocks
);
2883 block
= rb_entry(rb_node
, struct tree_block
, rb_node
);
2884 if (!block
->key_ready
)
2885 reada_tree_block(rc
, block
);
2886 rb_node
= rb_next(rb_node
);
2889 rb_node
= rb_first(blocks
);
2891 block
= rb_entry(rb_node
, struct tree_block
, rb_node
);
2892 if (!block
->key_ready
) {
2893 err
= get_tree_block_key(rc
, block
);
2897 rb_node
= rb_next(rb_node
);
2900 rb_node
= rb_first(blocks
);
2902 block
= rb_entry(rb_node
, struct tree_block
, rb_node
);
2904 node
= build_backref_tree(rc
, &block
->key
,
2905 block
->level
, block
->bytenr
);
2907 err
= PTR_ERR(node
);
2911 ret
= relocate_tree_block(trans
, rc
, node
, &block
->key
,
2914 if (ret
!= -EAGAIN
|| rb_node
== rb_first(blocks
))
2918 rb_node
= rb_next(rb_node
);
2921 err
= finish_pending_nodes(trans
, rc
, path
, err
);
2924 btrfs_free_path(path
);
2926 free_block_list(blocks
);
2930 static noinline_for_stack
2931 int prealloc_file_extent_cluster(struct inode
*inode
,
2932 struct file_extent_cluster
*cluster
)
2937 u64 offset
= BTRFS_I(inode
)->index_cnt
;
2942 BUG_ON(cluster
->start
!= cluster
->boundary
[0]);
2943 mutex_lock(&inode
->i_mutex
);
2945 ret
= btrfs_check_data_free_space(inode
, cluster
->end
+
2946 1 - cluster
->start
);
2950 while (nr
< cluster
->nr
) {
2951 start
= cluster
->boundary
[nr
] - offset
;
2952 if (nr
+ 1 < cluster
->nr
)
2953 end
= cluster
->boundary
[nr
+ 1] - 1 - offset
;
2955 end
= cluster
->end
- offset
;
2957 lock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
2958 num_bytes
= end
+ 1 - start
;
2959 ret
= btrfs_prealloc_file_range(inode
, 0, start
,
2960 num_bytes
, num_bytes
,
2961 end
+ 1, &alloc_hint
);
2962 unlock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
2967 btrfs_free_reserved_data_space(inode
, cluster
->end
+
2968 1 - cluster
->start
);
2970 mutex_unlock(&inode
->i_mutex
);
2974 static noinline_for_stack
2975 int setup_extent_mapping(struct inode
*inode
, u64 start
, u64 end
,
2978 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
2979 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
2980 struct extent_map
*em
;
2983 em
= alloc_extent_map();
2988 em
->len
= end
+ 1 - start
;
2989 em
->block_len
= em
->len
;
2990 em
->block_start
= block_start
;
2991 em
->bdev
= root
->fs_info
->fs_devices
->latest_bdev
;
2992 set_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
2994 lock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
2996 write_lock(&em_tree
->lock
);
2997 ret
= add_extent_mapping(em_tree
, em
, 0);
2998 write_unlock(&em_tree
->lock
);
2999 if (ret
!= -EEXIST
) {
3000 free_extent_map(em
);
3003 btrfs_drop_extent_cache(inode
, start
, end
, 0);
3005 unlock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
3009 static int relocate_file_extent_cluster(struct inode
*inode
,
3010 struct file_extent_cluster
*cluster
)
3014 u64 offset
= BTRFS_I(inode
)->index_cnt
;
3015 unsigned long index
;
3016 unsigned long last_index
;
3018 struct file_ra_state
*ra
;
3019 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
3026 ra
= kzalloc(sizeof(*ra
), GFP_NOFS
);
3030 ret
= prealloc_file_extent_cluster(inode
, cluster
);
3034 file_ra_state_init(ra
, inode
->i_mapping
);
3036 ret
= setup_extent_mapping(inode
, cluster
->start
- offset
,
3037 cluster
->end
- offset
, cluster
->start
);
3041 index
= (cluster
->start
- offset
) >> PAGE_CACHE_SHIFT
;
3042 last_index
= (cluster
->end
- offset
) >> PAGE_CACHE_SHIFT
;
3043 while (index
<= last_index
) {
3044 ret
= btrfs_delalloc_reserve_metadata(inode
, PAGE_CACHE_SIZE
);
3048 page
= find_lock_page(inode
->i_mapping
, index
);
3050 page_cache_sync_readahead(inode
->i_mapping
,
3052 last_index
+ 1 - index
);
3053 page
= find_or_create_page(inode
->i_mapping
, index
,
3056 btrfs_delalloc_release_metadata(inode
,
3063 if (PageReadahead(page
)) {
3064 page_cache_async_readahead(inode
->i_mapping
,
3065 ra
, NULL
, page
, index
,
3066 last_index
+ 1 - index
);
3069 if (!PageUptodate(page
)) {
3070 btrfs_readpage(NULL
, page
);
3072 if (!PageUptodate(page
)) {
3074 page_cache_release(page
);
3075 btrfs_delalloc_release_metadata(inode
,
3082 page_start
= page_offset(page
);
3083 page_end
= page_start
+ PAGE_CACHE_SIZE
- 1;
3085 lock_extent(&BTRFS_I(inode
)->io_tree
, page_start
, page_end
);
3087 set_page_extent_mapped(page
);
3089 if (nr
< cluster
->nr
&&
3090 page_start
+ offset
== cluster
->boundary
[nr
]) {
3091 set_extent_bits(&BTRFS_I(inode
)->io_tree
,
3092 page_start
, page_end
,
3093 EXTENT_BOUNDARY
, GFP_NOFS
);
3097 btrfs_set_extent_delalloc(inode
, page_start
, page_end
, NULL
);
3098 set_page_dirty(page
);
3100 unlock_extent(&BTRFS_I(inode
)->io_tree
,
3101 page_start
, page_end
);
3103 page_cache_release(page
);
3106 balance_dirty_pages_ratelimited(inode
->i_mapping
);
3107 btrfs_throttle(BTRFS_I(inode
)->root
);
3109 WARN_ON(nr
!= cluster
->nr
);
3115 static noinline_for_stack
3116 int relocate_data_extent(struct inode
*inode
, struct btrfs_key
*extent_key
,
3117 struct file_extent_cluster
*cluster
)
3121 if (cluster
->nr
> 0 && extent_key
->objectid
!= cluster
->end
+ 1) {
3122 ret
= relocate_file_extent_cluster(inode
, cluster
);
3129 cluster
->start
= extent_key
->objectid
;
3131 BUG_ON(cluster
->nr
>= MAX_EXTENTS
);
3132 cluster
->end
= extent_key
->objectid
+ extent_key
->offset
- 1;
3133 cluster
->boundary
[cluster
->nr
] = extent_key
->objectid
;
3136 if (cluster
->nr
>= MAX_EXTENTS
) {
3137 ret
= relocate_file_extent_cluster(inode
, cluster
);
3145 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3146 static int get_ref_objectid_v0(struct reloc_control
*rc
,
3147 struct btrfs_path
*path
,
3148 struct btrfs_key
*extent_key
,
3149 u64
*ref_objectid
, int *path_change
)
3151 struct btrfs_key key
;
3152 struct extent_buffer
*leaf
;
3153 struct btrfs_extent_ref_v0
*ref0
;
3157 leaf
= path
->nodes
[0];
3158 slot
= path
->slots
[0];
3160 if (slot
>= btrfs_header_nritems(leaf
)) {
3161 ret
= btrfs_next_leaf(rc
->extent_root
, path
);
3165 leaf
= path
->nodes
[0];
3166 slot
= path
->slots
[0];
3170 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
3171 if (key
.objectid
!= extent_key
->objectid
)
3174 if (key
.type
!= BTRFS_EXTENT_REF_V0_KEY
) {
3178 ref0
= btrfs_item_ptr(leaf
, slot
,
3179 struct btrfs_extent_ref_v0
);
3180 *ref_objectid
= btrfs_ref_objectid_v0(leaf
, ref0
);
3188 * helper to add a tree block to the list.
3189 * the major work is getting the generation and level of the block
3191 static int add_tree_block(struct reloc_control
*rc
,
3192 struct btrfs_key
*extent_key
,
3193 struct btrfs_path
*path
,
3194 struct rb_root
*blocks
)
3196 struct extent_buffer
*eb
;
3197 struct btrfs_extent_item
*ei
;
3198 struct btrfs_tree_block_info
*bi
;
3199 struct tree_block
*block
;
3200 struct rb_node
*rb_node
;
3205 eb
= path
->nodes
[0];
3206 item_size
= btrfs_item_size_nr(eb
, path
->slots
[0]);
3208 if (extent_key
->type
== BTRFS_METADATA_ITEM_KEY
||
3209 item_size
>= sizeof(*ei
) + sizeof(*bi
)) {
3210 ei
= btrfs_item_ptr(eb
, path
->slots
[0],
3211 struct btrfs_extent_item
);
3212 if (extent_key
->type
== BTRFS_EXTENT_ITEM_KEY
) {
3213 bi
= (struct btrfs_tree_block_info
*)(ei
+ 1);
3214 level
= btrfs_tree_block_level(eb
, bi
);
3216 level
= (int)extent_key
->offset
;
3218 generation
= btrfs_extent_generation(eb
, ei
);
3220 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3224 BUG_ON(item_size
!= sizeof(struct btrfs_extent_item_v0
));
3225 ret
= get_ref_objectid_v0(rc
, path
, extent_key
,
3229 BUG_ON(ref_owner
>= BTRFS_MAX_LEVEL
);
3230 level
= (int)ref_owner
;
3231 /* FIXME: get real generation */
3238 btrfs_release_path(path
);
3240 BUG_ON(level
== -1);
3242 block
= kmalloc(sizeof(*block
), GFP_NOFS
);
3246 block
->bytenr
= extent_key
->objectid
;
3247 block
->key
.objectid
= rc
->extent_root
->leafsize
;
3248 block
->key
.offset
= generation
;
3249 block
->level
= level
;
3250 block
->key_ready
= 0;
3252 rb_node
= tree_insert(blocks
, block
->bytenr
, &block
->rb_node
);
3254 backref_tree_panic(rb_node
, -EEXIST
, block
->bytenr
);
3260 * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY
3262 static int __add_tree_block(struct reloc_control
*rc
,
3263 u64 bytenr
, u32 blocksize
,
3264 struct rb_root
*blocks
)
3266 struct btrfs_path
*path
;
3267 struct btrfs_key key
;
3270 if (tree_block_processed(bytenr
, blocksize
, rc
))
3273 if (tree_search(blocks
, bytenr
))
3276 path
= btrfs_alloc_path();
3280 key
.objectid
= bytenr
;
3281 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
3282 key
.offset
= blocksize
;
3284 path
->search_commit_root
= 1;
3285 path
->skip_locking
= 1;
3286 ret
= btrfs_search_slot(NULL
, rc
->extent_root
, &key
, path
, 0, 0);
3290 btrfs_item_key_to_cpu(path
->nodes
[0], &key
, path
->slots
[0]);
3292 if (key
.objectid
== bytenr
&&
3293 key
.type
== BTRFS_METADATA_ITEM_KEY
)
3298 ret
= add_tree_block(rc
, &key
, path
, blocks
);
3300 btrfs_free_path(path
);
3305 * helper to check if the block use full backrefs for pointers in it
3307 static int block_use_full_backref(struct reloc_control
*rc
,
3308 struct extent_buffer
*eb
)
3313 if (btrfs_header_flag(eb
, BTRFS_HEADER_FLAG_RELOC
) ||
3314 btrfs_header_backref_rev(eb
) < BTRFS_MIXED_BACKREF_REV
)
3317 ret
= btrfs_lookup_extent_info(NULL
, rc
->extent_root
,
3318 eb
->start
, btrfs_header_level(eb
), 1,
3322 if (flags
& BTRFS_BLOCK_FLAG_FULL_BACKREF
)
3329 static int delete_block_group_cache(struct btrfs_fs_info
*fs_info
,
3330 struct inode
*inode
, u64 ino
)
3332 struct btrfs_key key
;
3333 struct btrfs_path
*path
;
3334 struct btrfs_root
*root
= fs_info
->tree_root
;
3335 struct btrfs_trans_handle
*trans
;
3342 key
.type
= BTRFS_INODE_ITEM_KEY
;
3345 inode
= btrfs_iget(fs_info
->sb
, &key
, root
, NULL
);
3346 if (IS_ERR(inode
) || is_bad_inode(inode
)) {
3353 ret
= btrfs_check_trunc_cache_free_space(root
,
3354 &fs_info
->global_block_rsv
);
3358 path
= btrfs_alloc_path();
3364 trans
= btrfs_join_transaction(root
);
3365 if (IS_ERR(trans
)) {
3366 btrfs_free_path(path
);
3367 ret
= PTR_ERR(trans
);
3371 ret
= btrfs_truncate_free_space_cache(root
, trans
, path
, inode
);
3373 btrfs_free_path(path
);
3374 btrfs_end_transaction(trans
, root
);
3375 btrfs_btree_balance_dirty(root
);
3382 * helper to add tree blocks for backref of type BTRFS_EXTENT_DATA_REF_KEY
3383 * this function scans fs tree to find blocks reference the data extent
3385 static int find_data_references(struct reloc_control
*rc
,
3386 struct btrfs_key
*extent_key
,
3387 struct extent_buffer
*leaf
,
3388 struct btrfs_extent_data_ref
*ref
,
3389 struct rb_root
*blocks
)
3391 struct btrfs_path
*path
;
3392 struct tree_block
*block
;
3393 struct btrfs_root
*root
;
3394 struct btrfs_file_extent_item
*fi
;
3395 struct rb_node
*rb_node
;
3396 struct btrfs_key key
;
3407 ref_root
= btrfs_extent_data_ref_root(leaf
, ref
);
3408 ref_objectid
= btrfs_extent_data_ref_objectid(leaf
, ref
);
3409 ref_offset
= btrfs_extent_data_ref_offset(leaf
, ref
);
3410 ref_count
= btrfs_extent_data_ref_count(leaf
, ref
);
3413 * This is an extent belonging to the free space cache, lets just delete
3414 * it and redo the search.
3416 if (ref_root
== BTRFS_ROOT_TREE_OBJECTID
) {
3417 ret
= delete_block_group_cache(rc
->extent_root
->fs_info
,
3418 NULL
, ref_objectid
);
3424 path
= btrfs_alloc_path();
3429 root
= read_fs_root(rc
->extent_root
->fs_info
, ref_root
);
3431 err
= PTR_ERR(root
);
3435 key
.objectid
= ref_objectid
;
3436 key
.type
= BTRFS_EXTENT_DATA_KEY
;
3437 if (ref_offset
> ((u64
)-1 << 32))
3440 key
.offset
= ref_offset
;
3442 path
->search_commit_root
= 1;
3443 path
->skip_locking
= 1;
3444 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
3450 leaf
= path
->nodes
[0];
3451 nritems
= btrfs_header_nritems(leaf
);
3453 * the references in tree blocks that use full backrefs
3454 * are not counted in
3456 if (block_use_full_backref(rc
, leaf
))
3460 rb_node
= tree_search(blocks
, leaf
->start
);
3465 path
->slots
[0] = nritems
;
3468 while (ref_count
> 0) {
3469 while (path
->slots
[0] >= nritems
) {
3470 ret
= btrfs_next_leaf(root
, path
);
3480 leaf
= path
->nodes
[0];
3481 nritems
= btrfs_header_nritems(leaf
);
3484 if (block_use_full_backref(rc
, leaf
))
3488 rb_node
= tree_search(blocks
, leaf
->start
);
3493 path
->slots
[0] = nritems
;
3497 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
3498 if (key
.objectid
!= ref_objectid
||
3499 key
.type
!= BTRFS_EXTENT_DATA_KEY
) {
3504 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
3505 struct btrfs_file_extent_item
);
3507 if (btrfs_file_extent_type(leaf
, fi
) ==
3508 BTRFS_FILE_EXTENT_INLINE
)
3511 if (btrfs_file_extent_disk_bytenr(leaf
, fi
) !=
3512 extent_key
->objectid
)
3515 key
.offset
-= btrfs_file_extent_offset(leaf
, fi
);
3516 if (key
.offset
!= ref_offset
)
3524 if (!tree_block_processed(leaf
->start
, leaf
->len
, rc
)) {
3525 block
= kmalloc(sizeof(*block
), GFP_NOFS
);
3530 block
->bytenr
= leaf
->start
;
3531 btrfs_item_key_to_cpu(leaf
, &block
->key
, 0);
3533 block
->key_ready
= 1;
3534 rb_node
= tree_insert(blocks
, block
->bytenr
,
3537 backref_tree_panic(rb_node
, -EEXIST
,
3543 path
->slots
[0] = nritems
;
3549 btrfs_free_path(path
);
3554 * helper to find all tree blocks that reference a given data extent
3556 static noinline_for_stack
3557 int add_data_references(struct reloc_control
*rc
,
3558 struct btrfs_key
*extent_key
,
3559 struct btrfs_path
*path
,
3560 struct rb_root
*blocks
)
3562 struct btrfs_key key
;
3563 struct extent_buffer
*eb
;
3564 struct btrfs_extent_data_ref
*dref
;
3565 struct btrfs_extent_inline_ref
*iref
;
3568 u32 blocksize
= btrfs_level_size(rc
->extent_root
, 0);
3572 eb
= path
->nodes
[0];
3573 ptr
= btrfs_item_ptr_offset(eb
, path
->slots
[0]);
3574 end
= ptr
+ btrfs_item_size_nr(eb
, path
->slots
[0]);
3575 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3576 if (ptr
+ sizeof(struct btrfs_extent_item_v0
) == end
)
3580 ptr
+= sizeof(struct btrfs_extent_item
);
3583 iref
= (struct btrfs_extent_inline_ref
*)ptr
;
3584 key
.type
= btrfs_extent_inline_ref_type(eb
, iref
);
3585 if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
) {
3586 key
.offset
= btrfs_extent_inline_ref_offset(eb
, iref
);
3587 ret
= __add_tree_block(rc
, key
.offset
, blocksize
,
3589 } else if (key
.type
== BTRFS_EXTENT_DATA_REF_KEY
) {
3590 dref
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
3591 ret
= find_data_references(rc
, extent_key
,
3596 ptr
+= btrfs_extent_inline_ref_size(key
.type
);
3602 eb
= path
->nodes
[0];
3603 if (path
->slots
[0] >= btrfs_header_nritems(eb
)) {
3604 ret
= btrfs_next_leaf(rc
->extent_root
, path
);
3611 eb
= path
->nodes
[0];
3614 btrfs_item_key_to_cpu(eb
, &key
, path
->slots
[0]);
3615 if (key
.objectid
!= extent_key
->objectid
)
3618 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3619 if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
||
3620 key
.type
== BTRFS_EXTENT_REF_V0_KEY
) {
3622 BUG_ON(key
.type
== BTRFS_EXTENT_REF_V0_KEY
);
3623 if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
) {
3625 ret
= __add_tree_block(rc
, key
.offset
, blocksize
,
3627 } else if (key
.type
== BTRFS_EXTENT_DATA_REF_KEY
) {
3628 dref
= btrfs_item_ptr(eb
, path
->slots
[0],
3629 struct btrfs_extent_data_ref
);
3630 ret
= find_data_references(rc
, extent_key
,
3641 btrfs_release_path(path
);
3643 free_block_list(blocks
);
3648 * helper to find next unprocessed extent
3650 static noinline_for_stack
3651 int find_next_extent(struct btrfs_trans_handle
*trans
,
3652 struct reloc_control
*rc
, struct btrfs_path
*path
,
3653 struct btrfs_key
*extent_key
)
3655 struct btrfs_key key
;
3656 struct extent_buffer
*leaf
;
3657 u64 start
, end
, last
;
3660 last
= rc
->block_group
->key
.objectid
+ rc
->block_group
->key
.offset
;
3663 if (rc
->search_start
>= last
) {
3668 key
.objectid
= rc
->search_start
;
3669 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
3672 path
->search_commit_root
= 1;
3673 path
->skip_locking
= 1;
3674 ret
= btrfs_search_slot(NULL
, rc
->extent_root
, &key
, path
,
3679 leaf
= path
->nodes
[0];
3680 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
3681 ret
= btrfs_next_leaf(rc
->extent_root
, path
);
3684 leaf
= path
->nodes
[0];
3687 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
3688 if (key
.objectid
>= last
) {
3693 if (key
.type
!= BTRFS_EXTENT_ITEM_KEY
&&
3694 key
.type
!= BTRFS_METADATA_ITEM_KEY
) {
3699 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
3700 key
.objectid
+ key
.offset
<= rc
->search_start
) {
3705 if (key
.type
== BTRFS_METADATA_ITEM_KEY
&&
3706 key
.objectid
+ rc
->extent_root
->leafsize
<=
3712 ret
= find_first_extent_bit(&rc
->processed_blocks
,
3713 key
.objectid
, &start
, &end
,
3714 EXTENT_DIRTY
, NULL
);
3716 if (ret
== 0 && start
<= key
.objectid
) {
3717 btrfs_release_path(path
);
3718 rc
->search_start
= end
+ 1;
3720 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
)
3721 rc
->search_start
= key
.objectid
+ key
.offset
;
3723 rc
->search_start
= key
.objectid
+
3724 rc
->extent_root
->leafsize
;
3725 memcpy(extent_key
, &key
, sizeof(key
));
3729 btrfs_release_path(path
);
3733 static void set_reloc_control(struct reloc_control
*rc
)
3735 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3737 mutex_lock(&fs_info
->reloc_mutex
);
3738 fs_info
->reloc_ctl
= rc
;
3739 mutex_unlock(&fs_info
->reloc_mutex
);
3742 static void unset_reloc_control(struct reloc_control
*rc
)
3744 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3746 mutex_lock(&fs_info
->reloc_mutex
);
3747 fs_info
->reloc_ctl
= NULL
;
3748 mutex_unlock(&fs_info
->reloc_mutex
);
3751 static int check_extent_flags(u64 flags
)
3753 if ((flags
& BTRFS_EXTENT_FLAG_DATA
) &&
3754 (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
))
3756 if (!(flags
& BTRFS_EXTENT_FLAG_DATA
) &&
3757 !(flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
))
3759 if ((flags
& BTRFS_EXTENT_FLAG_DATA
) &&
3760 (flags
& BTRFS_BLOCK_FLAG_FULL_BACKREF
))
3765 static noinline_for_stack
3766 int prepare_to_relocate(struct reloc_control
*rc
)
3768 struct btrfs_trans_handle
*trans
;
3771 rc
->block_rsv
= btrfs_alloc_block_rsv(rc
->extent_root
,
3772 BTRFS_BLOCK_RSV_TEMP
);
3777 * reserve some space for creating reloc trees.
3778 * btrfs_init_reloc_root will use them when there
3779 * is no reservation in transaction handle.
3781 ret
= btrfs_block_rsv_add(rc
->extent_root
, rc
->block_rsv
,
3782 rc
->extent_root
->nodesize
* 256,
3783 BTRFS_RESERVE_FLUSH_ALL
);
3787 memset(&rc
->cluster
, 0, sizeof(rc
->cluster
));
3788 rc
->search_start
= rc
->block_group
->key
.objectid
;
3789 rc
->extents_found
= 0;
3790 rc
->nodes_relocated
= 0;
3791 rc
->merging_rsv_size
= 0;
3793 rc
->create_reloc_tree
= 1;
3794 set_reloc_control(rc
);
3796 trans
= btrfs_join_transaction(rc
->extent_root
);
3797 if (IS_ERR(trans
)) {
3798 unset_reloc_control(rc
);
3800 * extent tree is not a ref_cow tree and has no reloc_root to
3801 * cleanup. And callers are responsible to free the above
3804 return PTR_ERR(trans
);
3806 btrfs_commit_transaction(trans
, rc
->extent_root
);
3810 static noinline_for_stack
int relocate_block_group(struct reloc_control
*rc
)
3812 struct rb_root blocks
= RB_ROOT
;
3813 struct btrfs_key key
;
3814 struct btrfs_trans_handle
*trans
= NULL
;
3815 struct btrfs_path
*path
;
3816 struct btrfs_extent_item
*ei
;
3823 path
= btrfs_alloc_path();
3828 ret
= prepare_to_relocate(rc
);
3836 trans
= btrfs_start_transaction(rc
->extent_root
, 0);
3837 if (IS_ERR(trans
)) {
3838 err
= PTR_ERR(trans
);
3843 if (update_backref_cache(trans
, &rc
->backref_cache
)) {
3844 btrfs_end_transaction(trans
, rc
->extent_root
);
3848 ret
= find_next_extent(trans
, rc
, path
, &key
);
3854 rc
->extents_found
++;
3856 ei
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
3857 struct btrfs_extent_item
);
3858 item_size
= btrfs_item_size_nr(path
->nodes
[0], path
->slots
[0]);
3859 if (item_size
>= sizeof(*ei
)) {
3860 flags
= btrfs_extent_flags(path
->nodes
[0], ei
);
3861 ret
= check_extent_flags(flags
);
3865 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3867 int path_change
= 0;
3870 sizeof(struct btrfs_extent_item_v0
));
3871 ret
= get_ref_objectid_v0(rc
, path
, &key
, &ref_owner
,
3873 if (ref_owner
< BTRFS_FIRST_FREE_OBJECTID
)
3874 flags
= BTRFS_EXTENT_FLAG_TREE_BLOCK
;
3876 flags
= BTRFS_EXTENT_FLAG_DATA
;
3879 btrfs_release_path(path
);
3881 path
->search_commit_root
= 1;
3882 path
->skip_locking
= 1;
3883 ret
= btrfs_search_slot(NULL
, rc
->extent_root
,
3896 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
) {
3897 ret
= add_tree_block(rc
, &key
, path
, &blocks
);
3898 } else if (rc
->stage
== UPDATE_DATA_PTRS
&&
3899 (flags
& BTRFS_EXTENT_FLAG_DATA
)) {
3900 ret
= add_data_references(rc
, &key
, path
, &blocks
);
3902 btrfs_release_path(path
);
3910 if (!RB_EMPTY_ROOT(&blocks
)) {
3911 ret
= relocate_tree_blocks(trans
, rc
, &blocks
);
3913 if (ret
!= -EAGAIN
) {
3917 rc
->extents_found
--;
3918 rc
->search_start
= key
.objectid
;
3922 ret
= btrfs_block_rsv_check(rc
->extent_root
, rc
->block_rsv
, 5);
3924 if (ret
!= -ENOSPC
) {
3929 rc
->commit_transaction
= 1;
3932 if (rc
->commit_transaction
) {
3933 rc
->commit_transaction
= 0;
3934 ret
= btrfs_commit_transaction(trans
, rc
->extent_root
);
3937 btrfs_end_transaction_throttle(trans
, rc
->extent_root
);
3938 btrfs_btree_balance_dirty(rc
->extent_root
);
3942 if (rc
->stage
== MOVE_DATA_EXTENTS
&&
3943 (flags
& BTRFS_EXTENT_FLAG_DATA
)) {
3944 rc
->found_file_extent
= 1;
3945 ret
= relocate_data_extent(rc
->data_inode
,
3946 &key
, &rc
->cluster
);
3953 if (trans
&& progress
&& err
== -ENOSPC
) {
3954 ret
= btrfs_force_chunk_alloc(trans
, rc
->extent_root
,
3955 rc
->block_group
->flags
);
3963 btrfs_release_path(path
);
3964 clear_extent_bits(&rc
->processed_blocks
, 0, (u64
)-1, EXTENT_DIRTY
,
3968 btrfs_end_transaction_throttle(trans
, rc
->extent_root
);
3969 btrfs_btree_balance_dirty(rc
->extent_root
);
3973 ret
= relocate_file_extent_cluster(rc
->data_inode
,
3979 rc
->create_reloc_tree
= 0;
3980 set_reloc_control(rc
);
3982 backref_cache_cleanup(&rc
->backref_cache
);
3983 btrfs_block_rsv_release(rc
->extent_root
, rc
->block_rsv
, (u64
)-1);
3985 err
= prepare_to_merge(rc
, err
);
3987 merge_reloc_roots(rc
);
3989 rc
->merge_reloc_tree
= 0;
3990 unset_reloc_control(rc
);
3991 btrfs_block_rsv_release(rc
->extent_root
, rc
->block_rsv
, (u64
)-1);
3993 /* get rid of pinned extents */
3994 trans
= btrfs_join_transaction(rc
->extent_root
);
3996 err
= PTR_ERR(trans
);
3998 btrfs_commit_transaction(trans
, rc
->extent_root
);
4000 btrfs_free_block_rsv(rc
->extent_root
, rc
->block_rsv
);
4001 btrfs_free_path(path
);
4005 static int __insert_orphan_inode(struct btrfs_trans_handle
*trans
,
4006 struct btrfs_root
*root
, u64 objectid
)
4008 struct btrfs_path
*path
;
4009 struct btrfs_inode_item
*item
;
4010 struct extent_buffer
*leaf
;
4013 path
= btrfs_alloc_path();
4017 ret
= btrfs_insert_empty_inode(trans
, root
, path
, objectid
);
4021 leaf
= path
->nodes
[0];
4022 item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_inode_item
);
4023 memset_extent_buffer(leaf
, 0, (unsigned long)item
, sizeof(*item
));
4024 btrfs_set_inode_generation(leaf
, item
, 1);
4025 btrfs_set_inode_size(leaf
, item
, 0);
4026 btrfs_set_inode_mode(leaf
, item
, S_IFREG
| 0600);
4027 btrfs_set_inode_flags(leaf
, item
, BTRFS_INODE_NOCOMPRESS
|
4028 BTRFS_INODE_PREALLOC
);
4029 btrfs_mark_buffer_dirty(leaf
);
4030 btrfs_release_path(path
);
4032 btrfs_free_path(path
);
4037 * helper to create inode for data relocation.
4038 * the inode is in data relocation tree and its link count is 0
4040 static noinline_for_stack
4041 struct inode
*create_reloc_inode(struct btrfs_fs_info
*fs_info
,
4042 struct btrfs_block_group_cache
*group
)
4044 struct inode
*inode
= NULL
;
4045 struct btrfs_trans_handle
*trans
;
4046 struct btrfs_root
*root
;
4047 struct btrfs_key key
;
4048 u64 objectid
= BTRFS_FIRST_FREE_OBJECTID
;
4051 root
= read_fs_root(fs_info
, BTRFS_DATA_RELOC_TREE_OBJECTID
);
4053 return ERR_CAST(root
);
4055 trans
= btrfs_start_transaction(root
, 6);
4057 return ERR_CAST(trans
);
4059 err
= btrfs_find_free_objectid(root
, &objectid
);
4063 err
= __insert_orphan_inode(trans
, root
, objectid
);
4066 key
.objectid
= objectid
;
4067 key
.type
= BTRFS_INODE_ITEM_KEY
;
4069 inode
= btrfs_iget(root
->fs_info
->sb
, &key
, root
, NULL
);
4070 BUG_ON(IS_ERR(inode
) || is_bad_inode(inode
));
4071 BTRFS_I(inode
)->index_cnt
= group
->key
.objectid
;
4073 err
= btrfs_orphan_add(trans
, inode
);
4075 btrfs_end_transaction(trans
, root
);
4076 btrfs_btree_balance_dirty(root
);
4080 inode
= ERR_PTR(err
);
4085 static struct reloc_control
*alloc_reloc_control(struct btrfs_fs_info
*fs_info
)
4087 struct reloc_control
*rc
;
4089 rc
= kzalloc(sizeof(*rc
), GFP_NOFS
);
4093 INIT_LIST_HEAD(&rc
->reloc_roots
);
4094 backref_cache_init(&rc
->backref_cache
);
4095 mapping_tree_init(&rc
->reloc_root_tree
);
4096 extent_io_tree_init(&rc
->processed_blocks
,
4097 fs_info
->btree_inode
->i_mapping
);
4102 * function to relocate all extents in a block group.
4104 int btrfs_relocate_block_group(struct btrfs_root
*extent_root
, u64 group_start
)
4106 struct btrfs_fs_info
*fs_info
= extent_root
->fs_info
;
4107 struct reloc_control
*rc
;
4108 struct inode
*inode
;
4109 struct btrfs_path
*path
;
4114 rc
= alloc_reloc_control(fs_info
);
4118 rc
->extent_root
= extent_root
;
4120 rc
->block_group
= btrfs_lookup_block_group(fs_info
, group_start
);
4121 BUG_ON(!rc
->block_group
);
4123 if (!rc
->block_group
->ro
) {
4124 ret
= btrfs_set_block_group_ro(extent_root
, rc
->block_group
);
4132 path
= btrfs_alloc_path();
4138 inode
= lookup_free_space_inode(fs_info
->tree_root
, rc
->block_group
,
4140 btrfs_free_path(path
);
4143 ret
= delete_block_group_cache(fs_info
, inode
, 0);
4145 ret
= PTR_ERR(inode
);
4147 if (ret
&& ret
!= -ENOENT
) {
4152 rc
->data_inode
= create_reloc_inode(fs_info
, rc
->block_group
);
4153 if (IS_ERR(rc
->data_inode
)) {
4154 err
= PTR_ERR(rc
->data_inode
);
4155 rc
->data_inode
= NULL
;
4159 printk(KERN_INFO
"btrfs: relocating block group %llu flags %llu\n",
4160 (unsigned long long)rc
->block_group
->key
.objectid
,
4161 (unsigned long long)rc
->block_group
->flags
);
4163 ret
= btrfs_start_delalloc_inodes(fs_info
->tree_root
, 0);
4168 btrfs_wait_ordered_extents(fs_info
->tree_root
, 0);
4171 mutex_lock(&fs_info
->cleaner_mutex
);
4172 ret
= relocate_block_group(rc
);
4173 mutex_unlock(&fs_info
->cleaner_mutex
);
4179 if (rc
->extents_found
== 0)
4182 printk(KERN_INFO
"btrfs: found %llu extents\n",
4183 (unsigned long long)rc
->extents_found
);
4185 if (rc
->stage
== MOVE_DATA_EXTENTS
&& rc
->found_file_extent
) {
4186 btrfs_wait_ordered_range(rc
->data_inode
, 0, (u64
)-1);
4187 invalidate_mapping_pages(rc
->data_inode
->i_mapping
,
4189 rc
->stage
= UPDATE_DATA_PTRS
;
4193 filemap_write_and_wait_range(fs_info
->btree_inode
->i_mapping
,
4194 rc
->block_group
->key
.objectid
,
4195 rc
->block_group
->key
.objectid
+
4196 rc
->block_group
->key
.offset
- 1);
4198 WARN_ON(rc
->block_group
->pinned
> 0);
4199 WARN_ON(rc
->block_group
->reserved
> 0);
4200 WARN_ON(btrfs_block_group_used(&rc
->block_group
->item
) > 0);
4203 btrfs_set_block_group_rw(extent_root
, rc
->block_group
);
4204 iput(rc
->data_inode
);
4205 btrfs_put_block_group(rc
->block_group
);
4210 static noinline_for_stack
int mark_garbage_root(struct btrfs_root
*root
)
4212 struct btrfs_trans_handle
*trans
;
4215 trans
= btrfs_start_transaction(root
->fs_info
->tree_root
, 0);
4217 return PTR_ERR(trans
);
4219 memset(&root
->root_item
.drop_progress
, 0,
4220 sizeof(root
->root_item
.drop_progress
));
4221 root
->root_item
.drop_level
= 0;
4222 btrfs_set_root_refs(&root
->root_item
, 0);
4223 ret
= btrfs_update_root(trans
, root
->fs_info
->tree_root
,
4224 &root
->root_key
, &root
->root_item
);
4226 err
= btrfs_end_transaction(trans
, root
->fs_info
->tree_root
);
4233 * recover relocation interrupted by system crash.
4235 * this function resumes merging reloc trees with corresponding fs trees.
4236 * this is important for keeping the sharing of tree blocks
4238 int btrfs_recover_relocation(struct btrfs_root
*root
)
4240 LIST_HEAD(reloc_roots
);
4241 struct btrfs_key key
;
4242 struct btrfs_root
*fs_root
;
4243 struct btrfs_root
*reloc_root
;
4244 struct btrfs_path
*path
;
4245 struct extent_buffer
*leaf
;
4246 struct reloc_control
*rc
= NULL
;
4247 struct btrfs_trans_handle
*trans
;
4251 path
= btrfs_alloc_path();
4256 key
.objectid
= BTRFS_TREE_RELOC_OBJECTID
;
4257 key
.type
= BTRFS_ROOT_ITEM_KEY
;
4258 key
.offset
= (u64
)-1;
4261 ret
= btrfs_search_slot(NULL
, root
->fs_info
->tree_root
, &key
,
4268 if (path
->slots
[0] == 0)
4272 leaf
= path
->nodes
[0];
4273 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
4274 btrfs_release_path(path
);
4276 if (key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
||
4277 key
.type
!= BTRFS_ROOT_ITEM_KEY
)
4280 reloc_root
= btrfs_read_fs_root_no_radix(root
, &key
);
4281 if (IS_ERR(reloc_root
)) {
4282 err
= PTR_ERR(reloc_root
);
4286 list_add(&reloc_root
->root_list
, &reloc_roots
);
4288 if (btrfs_root_refs(&reloc_root
->root_item
) > 0) {
4289 fs_root
= read_fs_root(root
->fs_info
,
4290 reloc_root
->root_key
.offset
);
4291 if (IS_ERR(fs_root
)) {
4292 ret
= PTR_ERR(fs_root
);
4293 if (ret
!= -ENOENT
) {
4297 ret
= mark_garbage_root(reloc_root
);
4305 if (key
.offset
== 0)
4310 btrfs_release_path(path
);
4312 if (list_empty(&reloc_roots
))
4315 rc
= alloc_reloc_control(root
->fs_info
);
4321 rc
->extent_root
= root
->fs_info
->extent_root
;
4323 set_reloc_control(rc
);
4325 trans
= btrfs_join_transaction(rc
->extent_root
);
4326 if (IS_ERR(trans
)) {
4327 unset_reloc_control(rc
);
4328 err
= PTR_ERR(trans
);
4332 rc
->merge_reloc_tree
= 1;
4334 while (!list_empty(&reloc_roots
)) {
4335 reloc_root
= list_entry(reloc_roots
.next
,
4336 struct btrfs_root
, root_list
);
4337 list_del(&reloc_root
->root_list
);
4339 if (btrfs_root_refs(&reloc_root
->root_item
) == 0) {
4340 list_add_tail(&reloc_root
->root_list
,
4345 fs_root
= read_fs_root(root
->fs_info
,
4346 reloc_root
->root_key
.offset
);
4347 if (IS_ERR(fs_root
)) {
4348 err
= PTR_ERR(fs_root
);
4352 err
= __add_reloc_root(reloc_root
);
4353 BUG_ON(err
< 0); /* -ENOMEM or logic error */
4354 fs_root
->reloc_root
= reloc_root
;
4357 err
= btrfs_commit_transaction(trans
, rc
->extent_root
);
4361 merge_reloc_roots(rc
);
4363 unset_reloc_control(rc
);
4365 trans
= btrfs_join_transaction(rc
->extent_root
);
4367 err
= PTR_ERR(trans
);
4369 err
= btrfs_commit_transaction(trans
, rc
->extent_root
);
4373 if (!list_empty(&reloc_roots
))
4374 free_reloc_roots(&reloc_roots
);
4376 btrfs_free_path(path
);
4379 /* cleanup orphan inode in data relocation tree */
4380 fs_root
= read_fs_root(root
->fs_info
,
4381 BTRFS_DATA_RELOC_TREE_OBJECTID
);
4382 if (IS_ERR(fs_root
))
4383 err
= PTR_ERR(fs_root
);
4385 err
= btrfs_orphan_cleanup(fs_root
);
4391 * helper to add ordered checksum for data relocation.
4393 * cloning checksum properly handles the nodatasum extents.
4394 * it also saves CPU time to re-calculate the checksum.
4396 int btrfs_reloc_clone_csums(struct inode
*inode
, u64 file_pos
, u64 len
)
4398 struct btrfs_ordered_sum
*sums
;
4399 struct btrfs_sector_sum
*sector_sum
;
4400 struct btrfs_ordered_extent
*ordered
;
4401 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
4407 ordered
= btrfs_lookup_ordered_extent(inode
, file_pos
);
4408 BUG_ON(ordered
->file_offset
!= file_pos
|| ordered
->len
!= len
);
4410 disk_bytenr
= file_pos
+ BTRFS_I(inode
)->index_cnt
;
4411 ret
= btrfs_lookup_csums_range(root
->fs_info
->csum_root
, disk_bytenr
,
4412 disk_bytenr
+ len
- 1, &list
, 0);
4416 while (!list_empty(&list
)) {
4417 sums
= list_entry(list
.next
, struct btrfs_ordered_sum
, list
);
4418 list_del_init(&sums
->list
);
4420 sector_sum
= sums
->sums
;
4421 sums
->bytenr
= ordered
->start
;
4424 while (offset
< sums
->len
) {
4425 sector_sum
->bytenr
+= ordered
->start
- disk_bytenr
;
4427 offset
+= root
->sectorsize
;
4430 btrfs_add_ordered_sum(inode
, ordered
, sums
);
4433 btrfs_put_ordered_extent(ordered
);
4437 void btrfs_reloc_cow_block(struct btrfs_trans_handle
*trans
,
4438 struct btrfs_root
*root
, struct extent_buffer
*buf
,
4439 struct extent_buffer
*cow
)
4441 struct reloc_control
*rc
;
4442 struct backref_node
*node
;
4447 rc
= root
->fs_info
->reloc_ctl
;
4451 BUG_ON(rc
->stage
== UPDATE_DATA_PTRS
&&
4452 root
->root_key
.objectid
== BTRFS_DATA_RELOC_TREE_OBJECTID
);
4454 level
= btrfs_header_level(buf
);
4455 if (btrfs_header_generation(buf
) <=
4456 btrfs_root_last_snapshot(&root
->root_item
))
4459 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
&&
4460 rc
->create_reloc_tree
) {
4461 WARN_ON(!first_cow
&& level
== 0);
4463 node
= rc
->backref_cache
.path
[level
];
4464 BUG_ON(node
->bytenr
!= buf
->start
&&
4465 node
->new_bytenr
!= buf
->start
);
4467 drop_node_buffer(node
);
4468 extent_buffer_get(cow
);
4470 node
->new_bytenr
= cow
->start
;
4472 if (!node
->pending
) {
4473 list_move_tail(&node
->list
,
4474 &rc
->backref_cache
.pending
[level
]);
4479 __mark_block_processed(rc
, node
);
4481 if (first_cow
&& level
> 0)
4482 rc
->nodes_relocated
+= buf
->len
;
4485 if (level
== 0 && first_cow
&& rc
->stage
== UPDATE_DATA_PTRS
) {
4486 ret
= replace_file_extents(trans
, rc
, root
, cow
);
4492 * called before creating snapshot. it calculates metadata reservation
4493 * requried for relocating tree blocks in the snapshot
4495 void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle
*trans
,
4496 struct btrfs_pending_snapshot
*pending
,
4497 u64
*bytes_to_reserve
)
4499 struct btrfs_root
*root
;
4500 struct reloc_control
*rc
;
4502 root
= pending
->root
;
4503 if (!root
->reloc_root
)
4506 rc
= root
->fs_info
->reloc_ctl
;
4507 if (!rc
->merge_reloc_tree
)
4510 root
= root
->reloc_root
;
4511 BUG_ON(btrfs_root_refs(&root
->root_item
) == 0);
4513 * relocation is in the stage of merging trees. the space
4514 * used by merging a reloc tree is twice the size of
4515 * relocated tree nodes in the worst case. half for cowing
4516 * the reloc tree, half for cowing the fs tree. the space
4517 * used by cowing the reloc tree will be freed after the
4518 * tree is dropped. if we create snapshot, cowing the fs
4519 * tree may use more space than it frees. so we need
4520 * reserve extra space.
4522 *bytes_to_reserve
+= rc
->nodes_relocated
;
4526 * called after snapshot is created. migrate block reservation
4527 * and create reloc root for the newly created snapshot
4529 int btrfs_reloc_post_snapshot(struct btrfs_trans_handle
*trans
,
4530 struct btrfs_pending_snapshot
*pending
)
4532 struct btrfs_root
*root
= pending
->root
;
4533 struct btrfs_root
*reloc_root
;
4534 struct btrfs_root
*new_root
;
4535 struct reloc_control
*rc
;
4538 if (!root
->reloc_root
)
4541 rc
= root
->fs_info
->reloc_ctl
;
4542 rc
->merging_rsv_size
+= rc
->nodes_relocated
;
4544 if (rc
->merge_reloc_tree
) {
4545 ret
= btrfs_block_rsv_migrate(&pending
->block_rsv
,
4547 rc
->nodes_relocated
);
4552 new_root
= pending
->snap
;
4553 reloc_root
= create_reloc_root(trans
, root
->reloc_root
,
4554 new_root
->root_key
.objectid
);
4555 if (IS_ERR(reloc_root
))
4556 return PTR_ERR(reloc_root
);
4558 ret
= __add_reloc_root(reloc_root
);
4560 new_root
->reloc_root
= reloc_root
;
4562 if (rc
->create_reloc_tree
)
4563 ret
= clone_backref_node(trans
, rc
, root
, reloc_root
);