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];
97 #define RELOCATION_RESERVED_NODES 256
99 struct backref_cache
{
100 /* red black tree of all backref nodes in the cache */
101 struct rb_root rb_root
;
102 /* for passing backref nodes to btrfs_reloc_cow_block */
103 struct backref_node
*path
[BTRFS_MAX_LEVEL
];
105 * list of blocks that have been cowed but some block
106 * pointers in upper level blocks may not reflect the
109 struct list_head pending
[BTRFS_MAX_LEVEL
];
110 /* list of backref nodes with no child node */
111 struct list_head leaves
;
112 /* list of blocks that have been cowed in current transaction */
113 struct list_head changed
;
114 /* list of detached backref node. */
115 struct list_head detached
;
124 * map address of tree root to tree
126 struct mapping_node
{
127 struct rb_node rb_node
;
132 struct mapping_tree
{
133 struct rb_root rb_root
;
138 * present a tree block to process
141 struct rb_node rb_node
;
143 struct btrfs_key key
;
144 unsigned int level
:8;
145 unsigned int key_ready
:1;
148 #define MAX_EXTENTS 128
150 struct file_extent_cluster
{
153 u64 boundary
[MAX_EXTENTS
];
157 struct reloc_control
{
158 /* block group to relocate */
159 struct btrfs_block_group_cache
*block_group
;
161 struct btrfs_root
*extent_root
;
162 /* inode for moving data */
163 struct inode
*data_inode
;
165 struct btrfs_block_rsv
*block_rsv
;
167 struct backref_cache backref_cache
;
169 struct file_extent_cluster cluster
;
170 /* tree blocks have been processed */
171 struct extent_io_tree processed_blocks
;
172 /* map start of tree root to corresponding reloc tree */
173 struct mapping_tree reloc_root_tree
;
174 /* list of reloc trees */
175 struct list_head reloc_roots
;
176 /* size of metadata reservation for merging reloc trees */
177 u64 merging_rsv_size
;
178 /* size of relocated tree nodes */
180 /* reserved size for block group relocation*/
186 unsigned int stage
:8;
187 unsigned int create_reloc_tree
:1;
188 unsigned int merge_reloc_tree
:1;
189 unsigned int found_file_extent
:1;
192 /* stages of data relocation */
193 #define MOVE_DATA_EXTENTS 0
194 #define UPDATE_DATA_PTRS 1
196 static void remove_backref_node(struct backref_cache
*cache
,
197 struct backref_node
*node
);
198 static void __mark_block_processed(struct reloc_control
*rc
,
199 struct backref_node
*node
);
201 static void mapping_tree_init(struct mapping_tree
*tree
)
203 tree
->rb_root
= RB_ROOT
;
204 spin_lock_init(&tree
->lock
);
207 static void backref_cache_init(struct backref_cache
*cache
)
210 cache
->rb_root
= RB_ROOT
;
211 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++)
212 INIT_LIST_HEAD(&cache
->pending
[i
]);
213 INIT_LIST_HEAD(&cache
->changed
);
214 INIT_LIST_HEAD(&cache
->detached
);
215 INIT_LIST_HEAD(&cache
->leaves
);
218 static void backref_cache_cleanup(struct backref_cache
*cache
)
220 struct backref_node
*node
;
223 while (!list_empty(&cache
->detached
)) {
224 node
= list_entry(cache
->detached
.next
,
225 struct backref_node
, list
);
226 remove_backref_node(cache
, node
);
229 while (!list_empty(&cache
->leaves
)) {
230 node
= list_entry(cache
->leaves
.next
,
231 struct backref_node
, lower
);
232 remove_backref_node(cache
, node
);
235 cache
->last_trans
= 0;
237 for (i
= 0; i
< BTRFS_MAX_LEVEL
; i
++)
238 BUG_ON(!list_empty(&cache
->pending
[i
]));
239 BUG_ON(!list_empty(&cache
->changed
));
240 BUG_ON(!list_empty(&cache
->detached
));
241 BUG_ON(!RB_EMPTY_ROOT(&cache
->rb_root
));
242 BUG_ON(cache
->nr_nodes
);
243 BUG_ON(cache
->nr_edges
);
246 static struct backref_node
*alloc_backref_node(struct backref_cache
*cache
)
248 struct backref_node
*node
;
250 node
= kzalloc(sizeof(*node
), GFP_NOFS
);
252 INIT_LIST_HEAD(&node
->list
);
253 INIT_LIST_HEAD(&node
->upper
);
254 INIT_LIST_HEAD(&node
->lower
);
255 RB_CLEAR_NODE(&node
->rb_node
);
261 static void free_backref_node(struct backref_cache
*cache
,
262 struct backref_node
*node
)
270 static struct backref_edge
*alloc_backref_edge(struct backref_cache
*cache
)
272 struct backref_edge
*edge
;
274 edge
= kzalloc(sizeof(*edge
), GFP_NOFS
);
280 static void free_backref_edge(struct backref_cache
*cache
,
281 struct backref_edge
*edge
)
289 static struct rb_node
*tree_insert(struct rb_root
*root
, u64 bytenr
,
290 struct rb_node
*node
)
292 struct rb_node
**p
= &root
->rb_node
;
293 struct rb_node
*parent
= NULL
;
294 struct tree_entry
*entry
;
298 entry
= rb_entry(parent
, struct tree_entry
, rb_node
);
300 if (bytenr
< entry
->bytenr
)
302 else if (bytenr
> entry
->bytenr
)
308 rb_link_node(node
, parent
, p
);
309 rb_insert_color(node
, root
);
313 static struct rb_node
*tree_search(struct rb_root
*root
, u64 bytenr
)
315 struct rb_node
*n
= root
->rb_node
;
316 struct tree_entry
*entry
;
319 entry
= rb_entry(n
, struct tree_entry
, rb_node
);
321 if (bytenr
< entry
->bytenr
)
323 else if (bytenr
> entry
->bytenr
)
331 static void backref_tree_panic(struct rb_node
*rb_node
, int errno
, u64 bytenr
)
334 struct btrfs_fs_info
*fs_info
= NULL
;
335 struct backref_node
*bnode
= rb_entry(rb_node
, struct backref_node
,
338 fs_info
= bnode
->root
->fs_info
;
339 btrfs_panic(fs_info
, errno
, "Inconsistency in backref cache "
340 "found at offset %llu\n", bytenr
);
344 * walk up backref nodes until reach node presents tree root
346 static struct backref_node
*walk_up_backref(struct backref_node
*node
,
347 struct backref_edge
*edges
[],
350 struct backref_edge
*edge
;
353 while (!list_empty(&node
->upper
)) {
354 edge
= list_entry(node
->upper
.next
,
355 struct backref_edge
, list
[LOWER
]);
357 node
= edge
->node
[UPPER
];
359 BUG_ON(node
->detached
);
365 * walk down backref nodes to find start of next reference path
367 static struct backref_node
*walk_down_backref(struct backref_edge
*edges
[],
370 struct backref_edge
*edge
;
371 struct backref_node
*lower
;
375 edge
= edges
[idx
- 1];
376 lower
= edge
->node
[LOWER
];
377 if (list_is_last(&edge
->list
[LOWER
], &lower
->upper
)) {
381 edge
= list_entry(edge
->list
[LOWER
].next
,
382 struct backref_edge
, list
[LOWER
]);
383 edges
[idx
- 1] = edge
;
385 return edge
->node
[UPPER
];
391 static void unlock_node_buffer(struct backref_node
*node
)
394 btrfs_tree_unlock(node
->eb
);
399 static void drop_node_buffer(struct backref_node
*node
)
402 unlock_node_buffer(node
);
403 free_extent_buffer(node
->eb
);
408 static void drop_backref_node(struct backref_cache
*tree
,
409 struct backref_node
*node
)
411 BUG_ON(!list_empty(&node
->upper
));
413 drop_node_buffer(node
);
414 list_del(&node
->list
);
415 list_del(&node
->lower
);
416 if (!RB_EMPTY_NODE(&node
->rb_node
))
417 rb_erase(&node
->rb_node
, &tree
->rb_root
);
418 free_backref_node(tree
, node
);
422 * remove a backref node from the backref cache
424 static void remove_backref_node(struct backref_cache
*cache
,
425 struct backref_node
*node
)
427 struct backref_node
*upper
;
428 struct backref_edge
*edge
;
433 BUG_ON(!node
->lowest
&& !node
->detached
);
434 while (!list_empty(&node
->upper
)) {
435 edge
= list_entry(node
->upper
.next
, struct backref_edge
,
437 upper
= edge
->node
[UPPER
];
438 list_del(&edge
->list
[LOWER
]);
439 list_del(&edge
->list
[UPPER
]);
440 free_backref_edge(cache
, edge
);
442 if (RB_EMPTY_NODE(&upper
->rb_node
)) {
443 BUG_ON(!list_empty(&node
->upper
));
444 drop_backref_node(cache
, node
);
450 * add the node to leaf node list if no other
451 * child block cached.
453 if (list_empty(&upper
->lower
)) {
454 list_add_tail(&upper
->lower
, &cache
->leaves
);
459 drop_backref_node(cache
, node
);
462 static void update_backref_node(struct backref_cache
*cache
,
463 struct backref_node
*node
, u64 bytenr
)
465 struct rb_node
*rb_node
;
466 rb_erase(&node
->rb_node
, &cache
->rb_root
);
467 node
->bytenr
= bytenr
;
468 rb_node
= tree_insert(&cache
->rb_root
, node
->bytenr
, &node
->rb_node
);
470 backref_tree_panic(rb_node
, -EEXIST
, bytenr
);
474 * update backref cache after a transaction commit
476 static int update_backref_cache(struct btrfs_trans_handle
*trans
,
477 struct backref_cache
*cache
)
479 struct backref_node
*node
;
482 if (cache
->last_trans
== 0) {
483 cache
->last_trans
= trans
->transid
;
487 if (cache
->last_trans
== trans
->transid
)
491 * detached nodes are used to avoid unnecessary backref
492 * lookup. transaction commit changes the extent tree.
493 * so the detached nodes are no longer useful.
495 while (!list_empty(&cache
->detached
)) {
496 node
= list_entry(cache
->detached
.next
,
497 struct backref_node
, list
);
498 remove_backref_node(cache
, node
);
501 while (!list_empty(&cache
->changed
)) {
502 node
= list_entry(cache
->changed
.next
,
503 struct backref_node
, list
);
504 list_del_init(&node
->list
);
505 BUG_ON(node
->pending
);
506 update_backref_node(cache
, node
, node
->new_bytenr
);
510 * some nodes can be left in the pending list if there were
511 * errors during processing the pending nodes.
513 for (level
= 0; level
< BTRFS_MAX_LEVEL
; level
++) {
514 list_for_each_entry(node
, &cache
->pending
[level
], list
) {
515 BUG_ON(!node
->pending
);
516 if (node
->bytenr
== node
->new_bytenr
)
518 update_backref_node(cache
, node
, node
->new_bytenr
);
522 cache
->last_trans
= 0;
527 static int should_ignore_root(struct btrfs_root
*root
)
529 struct btrfs_root
*reloc_root
;
534 reloc_root
= root
->reloc_root
;
538 if (btrfs_root_last_snapshot(&reloc_root
->root_item
) ==
539 root
->fs_info
->running_transaction
->transid
- 1)
542 * if there is reloc tree and it was created in previous
543 * transaction backref lookup can find the reloc tree,
544 * so backref node for the fs tree root is useless for
550 * find reloc tree by address of tree root
552 static struct btrfs_root
*find_reloc_root(struct reloc_control
*rc
,
555 struct rb_node
*rb_node
;
556 struct mapping_node
*node
;
557 struct btrfs_root
*root
= NULL
;
559 spin_lock(&rc
->reloc_root_tree
.lock
);
560 rb_node
= tree_search(&rc
->reloc_root_tree
.rb_root
, bytenr
);
562 node
= rb_entry(rb_node
, struct mapping_node
, rb_node
);
563 root
= (struct btrfs_root
*)node
->data
;
565 spin_unlock(&rc
->reloc_root_tree
.lock
);
569 static int is_cowonly_root(u64 root_objectid
)
571 if (root_objectid
== BTRFS_ROOT_TREE_OBJECTID
||
572 root_objectid
== BTRFS_EXTENT_TREE_OBJECTID
||
573 root_objectid
== BTRFS_CHUNK_TREE_OBJECTID
||
574 root_objectid
== BTRFS_DEV_TREE_OBJECTID
||
575 root_objectid
== BTRFS_TREE_LOG_OBJECTID
||
576 root_objectid
== BTRFS_CSUM_TREE_OBJECTID
||
577 root_objectid
== BTRFS_UUID_TREE_OBJECTID
||
578 root_objectid
== BTRFS_QUOTA_TREE_OBJECTID
)
583 static struct btrfs_root
*read_fs_root(struct btrfs_fs_info
*fs_info
,
586 struct btrfs_key key
;
588 key
.objectid
= root_objectid
;
589 key
.type
= BTRFS_ROOT_ITEM_KEY
;
590 if (is_cowonly_root(root_objectid
))
593 key
.offset
= (u64
)-1;
595 return btrfs_get_fs_root(fs_info
, &key
, false);
598 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
599 static noinline_for_stack
600 struct btrfs_root
*find_tree_root(struct reloc_control
*rc
,
601 struct extent_buffer
*leaf
,
602 struct btrfs_extent_ref_v0
*ref0
)
604 struct btrfs_root
*root
;
605 u64 root_objectid
= btrfs_ref_root_v0(leaf
, ref0
);
606 u64 generation
= btrfs_ref_generation_v0(leaf
, ref0
);
608 BUG_ON(root_objectid
== BTRFS_TREE_RELOC_OBJECTID
);
610 root
= read_fs_root(rc
->extent_root
->fs_info
, root_objectid
);
611 BUG_ON(IS_ERR(root
));
613 if (root
->ref_cows
&&
614 generation
!= btrfs_root_generation(&root
->root_item
))
621 static noinline_for_stack
622 int find_inline_backref(struct extent_buffer
*leaf
, int slot
,
623 unsigned long *ptr
, unsigned long *end
)
625 struct btrfs_key key
;
626 struct btrfs_extent_item
*ei
;
627 struct btrfs_tree_block_info
*bi
;
630 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
632 item_size
= btrfs_item_size_nr(leaf
, slot
);
633 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
634 if (item_size
< sizeof(*ei
)) {
635 WARN_ON(item_size
!= sizeof(struct btrfs_extent_item_v0
));
639 ei
= btrfs_item_ptr(leaf
, slot
, struct btrfs_extent_item
);
640 WARN_ON(!(btrfs_extent_flags(leaf
, ei
) &
641 BTRFS_EXTENT_FLAG_TREE_BLOCK
));
643 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
644 item_size
<= sizeof(*ei
) + sizeof(*bi
)) {
645 WARN_ON(item_size
< sizeof(*ei
) + sizeof(*bi
));
648 if (key
.type
== BTRFS_METADATA_ITEM_KEY
&&
649 item_size
<= sizeof(*ei
)) {
650 WARN_ON(item_size
< sizeof(*ei
));
654 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
) {
655 bi
= (struct btrfs_tree_block_info
*)(ei
+ 1);
656 *ptr
= (unsigned long)(bi
+ 1);
658 *ptr
= (unsigned long)(ei
+ 1);
660 *end
= (unsigned long)ei
+ item_size
;
665 * build backref tree for a given tree block. root of the backref tree
666 * corresponds the tree block, leaves of the backref tree correspond
667 * roots of b-trees that reference the tree block.
669 * the basic idea of this function is check backrefs of a given block
670 * to find upper level blocks that refernece the block, and then check
671 * bakcrefs of these upper level blocks recursively. the recursion stop
672 * when tree root is reached or backrefs for the block is cached.
674 * NOTE: if we find backrefs for a block are cached, we know backrefs
675 * for all upper level blocks that directly/indirectly reference the
676 * block are also cached.
678 static noinline_for_stack
679 struct backref_node
*build_backref_tree(struct reloc_control
*rc
,
680 struct btrfs_key
*node_key
,
681 int level
, u64 bytenr
)
683 struct backref_cache
*cache
= &rc
->backref_cache
;
684 struct btrfs_path
*path1
;
685 struct btrfs_path
*path2
;
686 struct extent_buffer
*eb
;
687 struct btrfs_root
*root
;
688 struct backref_node
*cur
;
689 struct backref_node
*upper
;
690 struct backref_node
*lower
;
691 struct backref_node
*node
= NULL
;
692 struct backref_node
*exist
= NULL
;
693 struct backref_edge
*edge
;
694 struct rb_node
*rb_node
;
695 struct btrfs_key key
;
703 bool need_check
= true;
705 path1
= btrfs_alloc_path();
706 path2
= btrfs_alloc_path();
707 if (!path1
|| !path2
) {
714 node
= alloc_backref_node(cache
);
720 node
->bytenr
= bytenr
;
727 key
.objectid
= cur
->bytenr
;
728 key
.type
= BTRFS_METADATA_ITEM_KEY
;
729 key
.offset
= (u64
)-1;
731 path1
->search_commit_root
= 1;
732 path1
->skip_locking
= 1;
733 ret
= btrfs_search_slot(NULL
, rc
->extent_root
, &key
, path1
,
739 BUG_ON(!ret
|| !path1
->slots
[0]);
743 WARN_ON(cur
->checked
);
744 if (!list_empty(&cur
->upper
)) {
746 * the backref was added previously when processing
747 * backref of type BTRFS_TREE_BLOCK_REF_KEY
749 BUG_ON(!list_is_singular(&cur
->upper
));
750 edge
= list_entry(cur
->upper
.next
, struct backref_edge
,
752 BUG_ON(!list_empty(&edge
->list
[UPPER
]));
753 exist
= edge
->node
[UPPER
];
755 * add the upper level block to pending list if we need
759 list_add_tail(&edge
->list
[UPPER
], &list
);
766 eb
= path1
->nodes
[0];
769 if (path1
->slots
[0] >= btrfs_header_nritems(eb
)) {
770 ret
= btrfs_next_leaf(rc
->extent_root
, path1
);
777 eb
= path1
->nodes
[0];
780 btrfs_item_key_to_cpu(eb
, &key
, path1
->slots
[0]);
781 if (key
.objectid
!= cur
->bytenr
) {
786 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
||
787 key
.type
== BTRFS_METADATA_ITEM_KEY
) {
788 ret
= find_inline_backref(eb
, path1
->slots
[0],
796 /* update key for inline back ref */
797 struct btrfs_extent_inline_ref
*iref
;
798 iref
= (struct btrfs_extent_inline_ref
*)ptr
;
799 key
.type
= btrfs_extent_inline_ref_type(eb
, iref
);
800 key
.offset
= btrfs_extent_inline_ref_offset(eb
, iref
);
801 WARN_ON(key
.type
!= BTRFS_TREE_BLOCK_REF_KEY
&&
802 key
.type
!= BTRFS_SHARED_BLOCK_REF_KEY
);
806 ((key
.type
== BTRFS_TREE_BLOCK_REF_KEY
&&
807 exist
->owner
== key
.offset
) ||
808 (key
.type
== BTRFS_SHARED_BLOCK_REF_KEY
&&
809 exist
->bytenr
== key
.offset
))) {
814 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
815 if (key
.type
== BTRFS_SHARED_BLOCK_REF_KEY
||
816 key
.type
== BTRFS_EXTENT_REF_V0_KEY
) {
817 if (key
.type
== BTRFS_EXTENT_REF_V0_KEY
) {
818 struct btrfs_extent_ref_v0
*ref0
;
819 ref0
= btrfs_item_ptr(eb
, path1
->slots
[0],
820 struct btrfs_extent_ref_v0
);
821 if (key
.objectid
== key
.offset
) {
822 root
= find_tree_root(rc
, eb
, ref0
);
823 if (root
&& !should_ignore_root(root
))
826 list_add(&cur
->list
, &useless
);
829 if (is_cowonly_root(btrfs_ref_root_v0(eb
,
834 BUG_ON(key
.type
== BTRFS_EXTENT_REF_V0_KEY
);
835 if (key
.type
== BTRFS_SHARED_BLOCK_REF_KEY
) {
837 if (key
.objectid
== key
.offset
) {
839 * only root blocks of reloc trees use
840 * backref of this type.
842 root
= find_reloc_root(rc
, cur
->bytenr
);
848 edge
= alloc_backref_edge(cache
);
853 rb_node
= tree_search(&cache
->rb_root
, key
.offset
);
855 upper
= alloc_backref_node(cache
);
857 free_backref_edge(cache
, edge
);
861 upper
->bytenr
= key
.offset
;
862 upper
->level
= cur
->level
+ 1;
864 * backrefs for the upper level block isn't
865 * cached, add the block to pending list
867 list_add_tail(&edge
->list
[UPPER
], &list
);
869 upper
= rb_entry(rb_node
, struct backref_node
,
871 BUG_ON(!upper
->checked
);
872 INIT_LIST_HEAD(&edge
->list
[UPPER
]);
874 list_add_tail(&edge
->list
[LOWER
], &cur
->upper
);
875 edge
->node
[LOWER
] = cur
;
876 edge
->node
[UPPER
] = upper
;
879 } else if (key
.type
!= BTRFS_TREE_BLOCK_REF_KEY
) {
883 /* key.type == BTRFS_TREE_BLOCK_REF_KEY */
884 root
= read_fs_root(rc
->extent_root
->fs_info
, key
.offset
);
893 if (btrfs_root_level(&root
->root_item
) == cur
->level
) {
895 BUG_ON(btrfs_root_bytenr(&root
->root_item
) !=
897 if (should_ignore_root(root
))
898 list_add(&cur
->list
, &useless
);
904 level
= cur
->level
+ 1;
907 * searching the tree to find upper level blocks
908 * reference the block.
910 path2
->search_commit_root
= 1;
911 path2
->skip_locking
= 1;
912 path2
->lowest_level
= level
;
913 ret
= btrfs_search_slot(NULL
, root
, node_key
, path2
, 0, 0);
914 path2
->lowest_level
= 0;
919 if (ret
> 0 && path2
->slots
[level
] > 0)
920 path2
->slots
[level
]--;
922 eb
= path2
->nodes
[level
];
923 WARN_ON(btrfs_node_blockptr(eb
, path2
->slots
[level
]) !=
928 for (; level
< BTRFS_MAX_LEVEL
; level
++) {
929 if (!path2
->nodes
[level
]) {
930 BUG_ON(btrfs_root_bytenr(&root
->root_item
) !=
932 if (should_ignore_root(root
))
933 list_add(&lower
->list
, &useless
);
939 edge
= alloc_backref_edge(cache
);
945 eb
= path2
->nodes
[level
];
946 rb_node
= tree_search(&cache
->rb_root
, eb
->start
);
948 upper
= alloc_backref_node(cache
);
950 free_backref_edge(cache
, edge
);
954 upper
->bytenr
= eb
->start
;
955 upper
->owner
= btrfs_header_owner(eb
);
956 upper
->level
= lower
->level
+ 1;
961 * if we know the block isn't shared
962 * we can void checking its backrefs.
964 if (btrfs_block_can_be_shared(root
, eb
))
970 * add the block to pending list if we
971 * need check its backrefs, we only do this once
972 * while walking up a tree as we will catch
973 * anything else later on.
975 if (!upper
->checked
&& need_check
) {
977 list_add_tail(&edge
->list
[UPPER
],
980 INIT_LIST_HEAD(&edge
->list
[UPPER
]);
982 upper
= rb_entry(rb_node
, struct backref_node
,
984 BUG_ON(!upper
->checked
);
985 INIT_LIST_HEAD(&edge
->list
[UPPER
]);
987 upper
->owner
= btrfs_header_owner(eb
);
989 list_add_tail(&edge
->list
[LOWER
], &lower
->upper
);
990 edge
->node
[LOWER
] = lower
;
991 edge
->node
[UPPER
] = upper
;
998 btrfs_release_path(path2
);
1001 ptr
+= btrfs_extent_inline_ref_size(key
.type
);
1011 btrfs_release_path(path1
);
1016 /* the pending list isn't empty, take the first block to process */
1017 if (!list_empty(&list
)) {
1018 edge
= list_entry(list
.next
, struct backref_edge
, list
[UPPER
]);
1019 list_del_init(&edge
->list
[UPPER
]);
1020 cur
= edge
->node
[UPPER
];
1025 * everything goes well, connect backref nodes and insert backref nodes
1028 BUG_ON(!node
->checked
);
1029 cowonly
= node
->cowonly
;
1031 rb_node
= tree_insert(&cache
->rb_root
, node
->bytenr
,
1034 backref_tree_panic(rb_node
, -EEXIST
, node
->bytenr
);
1035 list_add_tail(&node
->lower
, &cache
->leaves
);
1038 list_for_each_entry(edge
, &node
->upper
, list
[LOWER
])
1039 list_add_tail(&edge
->list
[UPPER
], &list
);
1041 while (!list_empty(&list
)) {
1042 edge
= list_entry(list
.next
, struct backref_edge
, list
[UPPER
]);
1043 list_del_init(&edge
->list
[UPPER
]);
1044 upper
= edge
->node
[UPPER
];
1045 if (upper
->detached
) {
1046 list_del(&edge
->list
[LOWER
]);
1047 lower
= edge
->node
[LOWER
];
1048 free_backref_edge(cache
, edge
);
1049 if (list_empty(&lower
->upper
))
1050 list_add(&lower
->list
, &useless
);
1054 if (!RB_EMPTY_NODE(&upper
->rb_node
)) {
1055 if (upper
->lowest
) {
1056 list_del_init(&upper
->lower
);
1060 list_add_tail(&edge
->list
[UPPER
], &upper
->lower
);
1064 BUG_ON(!upper
->checked
);
1065 BUG_ON(cowonly
!= upper
->cowonly
);
1067 rb_node
= tree_insert(&cache
->rb_root
, upper
->bytenr
,
1070 backref_tree_panic(rb_node
, -EEXIST
,
1074 list_add_tail(&edge
->list
[UPPER
], &upper
->lower
);
1076 list_for_each_entry(edge
, &upper
->upper
, list
[LOWER
])
1077 list_add_tail(&edge
->list
[UPPER
], &list
);
1080 * process useless backref nodes. backref nodes for tree leaves
1081 * are deleted from the cache. backref nodes for upper level
1082 * tree blocks are left in the cache to avoid unnecessary backref
1085 while (!list_empty(&useless
)) {
1086 upper
= list_entry(useless
.next
, struct backref_node
, list
);
1087 list_del_init(&upper
->list
);
1088 BUG_ON(!list_empty(&upper
->upper
));
1091 if (upper
->lowest
) {
1092 list_del_init(&upper
->lower
);
1095 while (!list_empty(&upper
->lower
)) {
1096 edge
= list_entry(upper
->lower
.next
,
1097 struct backref_edge
, list
[UPPER
]);
1098 list_del(&edge
->list
[UPPER
]);
1099 list_del(&edge
->list
[LOWER
]);
1100 lower
= edge
->node
[LOWER
];
1101 free_backref_edge(cache
, edge
);
1103 if (list_empty(&lower
->upper
))
1104 list_add(&lower
->list
, &useless
);
1106 __mark_block_processed(rc
, upper
);
1107 if (upper
->level
> 0) {
1108 list_add(&upper
->list
, &cache
->detached
);
1109 upper
->detached
= 1;
1111 rb_erase(&upper
->rb_node
, &cache
->rb_root
);
1112 free_backref_node(cache
, upper
);
1116 btrfs_free_path(path1
);
1117 btrfs_free_path(path2
);
1119 while (!list_empty(&useless
)) {
1120 lower
= list_entry(useless
.next
,
1121 struct backref_node
, upper
);
1122 list_del_init(&lower
->upper
);
1125 INIT_LIST_HEAD(&list
);
1127 if (RB_EMPTY_NODE(&upper
->rb_node
)) {
1128 list_splice_tail(&upper
->upper
, &list
);
1129 free_backref_node(cache
, upper
);
1132 if (list_empty(&list
))
1135 edge
= list_entry(list
.next
, struct backref_edge
,
1137 list_del(&edge
->list
[LOWER
]);
1138 upper
= edge
->node
[UPPER
];
1139 free_backref_edge(cache
, edge
);
1141 return ERR_PTR(err
);
1143 BUG_ON(node
&& node
->detached
);
1148 * helper to add backref node for the newly created snapshot.
1149 * the backref node is created by cloning backref node that
1150 * corresponds to root of source tree
1152 static int clone_backref_node(struct btrfs_trans_handle
*trans
,
1153 struct reloc_control
*rc
,
1154 struct btrfs_root
*src
,
1155 struct btrfs_root
*dest
)
1157 struct btrfs_root
*reloc_root
= src
->reloc_root
;
1158 struct backref_cache
*cache
= &rc
->backref_cache
;
1159 struct backref_node
*node
= NULL
;
1160 struct backref_node
*new_node
;
1161 struct backref_edge
*edge
;
1162 struct backref_edge
*new_edge
;
1163 struct rb_node
*rb_node
;
1165 if (cache
->last_trans
> 0)
1166 update_backref_cache(trans
, cache
);
1168 rb_node
= tree_search(&cache
->rb_root
, src
->commit_root
->start
);
1170 node
= rb_entry(rb_node
, struct backref_node
, rb_node
);
1174 BUG_ON(node
->new_bytenr
!= reloc_root
->node
->start
);
1178 rb_node
= tree_search(&cache
->rb_root
,
1179 reloc_root
->commit_root
->start
);
1181 node
= rb_entry(rb_node
, struct backref_node
,
1183 BUG_ON(node
->detached
);
1190 new_node
= alloc_backref_node(cache
);
1194 new_node
->bytenr
= dest
->node
->start
;
1195 new_node
->level
= node
->level
;
1196 new_node
->lowest
= node
->lowest
;
1197 new_node
->checked
= 1;
1198 new_node
->root
= dest
;
1200 if (!node
->lowest
) {
1201 list_for_each_entry(edge
, &node
->lower
, list
[UPPER
]) {
1202 new_edge
= alloc_backref_edge(cache
);
1206 new_edge
->node
[UPPER
] = new_node
;
1207 new_edge
->node
[LOWER
] = edge
->node
[LOWER
];
1208 list_add_tail(&new_edge
->list
[UPPER
],
1212 list_add_tail(&new_node
->lower
, &cache
->leaves
);
1215 rb_node
= tree_insert(&cache
->rb_root
, new_node
->bytenr
,
1216 &new_node
->rb_node
);
1218 backref_tree_panic(rb_node
, -EEXIST
, new_node
->bytenr
);
1220 if (!new_node
->lowest
) {
1221 list_for_each_entry(new_edge
, &new_node
->lower
, list
[UPPER
]) {
1222 list_add_tail(&new_edge
->list
[LOWER
],
1223 &new_edge
->node
[LOWER
]->upper
);
1228 while (!list_empty(&new_node
->lower
)) {
1229 new_edge
= list_entry(new_node
->lower
.next
,
1230 struct backref_edge
, list
[UPPER
]);
1231 list_del(&new_edge
->list
[UPPER
]);
1232 free_backref_edge(cache
, new_edge
);
1234 free_backref_node(cache
, new_node
);
1239 * helper to add 'address of tree root -> reloc tree' mapping
1241 static int __must_check
__add_reloc_root(struct btrfs_root
*root
)
1243 struct rb_node
*rb_node
;
1244 struct mapping_node
*node
;
1245 struct reloc_control
*rc
= root
->fs_info
->reloc_ctl
;
1247 node
= kmalloc(sizeof(*node
), GFP_NOFS
);
1251 node
->bytenr
= root
->node
->start
;
1254 spin_lock(&rc
->reloc_root_tree
.lock
);
1255 rb_node
= tree_insert(&rc
->reloc_root_tree
.rb_root
,
1256 node
->bytenr
, &node
->rb_node
);
1257 spin_unlock(&rc
->reloc_root_tree
.lock
);
1259 btrfs_panic(root
->fs_info
, -EEXIST
, "Duplicate root found "
1260 "for start=%llu while inserting into relocation "
1261 "tree\n", node
->bytenr
);
1266 list_add_tail(&root
->root_list
, &rc
->reloc_roots
);
1271 * helper to delete the 'address of tree root -> reloc tree'
1274 static void __del_reloc_root(struct btrfs_root
*root
)
1276 struct rb_node
*rb_node
;
1277 struct mapping_node
*node
= NULL
;
1278 struct reloc_control
*rc
= root
->fs_info
->reloc_ctl
;
1280 spin_lock(&rc
->reloc_root_tree
.lock
);
1281 rb_node
= tree_search(&rc
->reloc_root_tree
.rb_root
,
1284 node
= rb_entry(rb_node
, struct mapping_node
, rb_node
);
1285 rb_erase(&node
->rb_node
, &rc
->reloc_root_tree
.rb_root
);
1287 spin_unlock(&rc
->reloc_root_tree
.lock
);
1291 BUG_ON((struct btrfs_root
*)node
->data
!= root
);
1293 spin_lock(&root
->fs_info
->trans_lock
);
1294 list_del_init(&root
->root_list
);
1295 spin_unlock(&root
->fs_info
->trans_lock
);
1300 * helper to update the 'address of tree root -> reloc tree'
1303 static int __update_reloc_root(struct btrfs_root
*root
, u64 new_bytenr
)
1305 struct rb_node
*rb_node
;
1306 struct mapping_node
*node
= NULL
;
1307 struct reloc_control
*rc
= root
->fs_info
->reloc_ctl
;
1309 spin_lock(&rc
->reloc_root_tree
.lock
);
1310 rb_node
= tree_search(&rc
->reloc_root_tree
.rb_root
,
1313 node
= rb_entry(rb_node
, struct mapping_node
, rb_node
);
1314 rb_erase(&node
->rb_node
, &rc
->reloc_root_tree
.rb_root
);
1316 spin_unlock(&rc
->reloc_root_tree
.lock
);
1320 BUG_ON((struct btrfs_root
*)node
->data
!= root
);
1322 spin_lock(&rc
->reloc_root_tree
.lock
);
1323 node
->bytenr
= new_bytenr
;
1324 rb_node
= tree_insert(&rc
->reloc_root_tree
.rb_root
,
1325 node
->bytenr
, &node
->rb_node
);
1326 spin_unlock(&rc
->reloc_root_tree
.lock
);
1328 backref_tree_panic(rb_node
, -EEXIST
, node
->bytenr
);
1332 static struct btrfs_root
*create_reloc_root(struct btrfs_trans_handle
*trans
,
1333 struct btrfs_root
*root
, u64 objectid
)
1335 struct btrfs_root
*reloc_root
;
1336 struct extent_buffer
*eb
;
1337 struct btrfs_root_item
*root_item
;
1338 struct btrfs_key root_key
;
1342 root_item
= kmalloc(sizeof(*root_item
), GFP_NOFS
);
1345 root_key
.objectid
= BTRFS_TREE_RELOC_OBJECTID
;
1346 root_key
.type
= BTRFS_ROOT_ITEM_KEY
;
1347 root_key
.offset
= objectid
;
1349 if (root
->root_key
.objectid
== objectid
) {
1350 /* called by btrfs_init_reloc_root */
1351 ret
= btrfs_copy_root(trans
, root
, root
->commit_root
, &eb
,
1352 BTRFS_TREE_RELOC_OBJECTID
);
1355 last_snap
= btrfs_root_last_snapshot(&root
->root_item
);
1356 btrfs_set_root_last_snapshot(&root
->root_item
,
1357 trans
->transid
- 1);
1360 * called by btrfs_reloc_post_snapshot_hook.
1361 * the source tree is a reloc tree, all tree blocks
1362 * modified after it was created have RELOC flag
1363 * set in their headers. so it's OK to not update
1364 * the 'last_snapshot'.
1366 ret
= btrfs_copy_root(trans
, root
, root
->node
, &eb
,
1367 BTRFS_TREE_RELOC_OBJECTID
);
1371 memcpy(root_item
, &root
->root_item
, sizeof(*root_item
));
1372 btrfs_set_root_bytenr(root_item
, eb
->start
);
1373 btrfs_set_root_level(root_item
, btrfs_header_level(eb
));
1374 btrfs_set_root_generation(root_item
, trans
->transid
);
1376 if (root
->root_key
.objectid
== objectid
) {
1377 btrfs_set_root_refs(root_item
, 0);
1378 memset(&root_item
->drop_progress
, 0,
1379 sizeof(struct btrfs_disk_key
));
1380 root_item
->drop_level
= 0;
1382 * abuse rtransid, it is safe because it is impossible to
1383 * receive data into a relocation tree.
1385 btrfs_set_root_rtransid(root_item
, last_snap
);
1386 btrfs_set_root_otransid(root_item
, trans
->transid
);
1389 btrfs_tree_unlock(eb
);
1390 free_extent_buffer(eb
);
1392 ret
= btrfs_insert_root(trans
, root
->fs_info
->tree_root
,
1393 &root_key
, root_item
);
1397 reloc_root
= btrfs_read_fs_root(root
->fs_info
->tree_root
, &root_key
);
1398 BUG_ON(IS_ERR(reloc_root
));
1399 reloc_root
->last_trans
= trans
->transid
;
1404 * create reloc tree for a given fs tree. reloc tree is just a
1405 * snapshot of the fs tree with special root objectid.
1407 int btrfs_init_reloc_root(struct btrfs_trans_handle
*trans
,
1408 struct btrfs_root
*root
)
1410 struct btrfs_root
*reloc_root
;
1411 struct reloc_control
*rc
= root
->fs_info
->reloc_ctl
;
1412 struct btrfs_block_rsv
*rsv
;
1416 if (root
->reloc_root
) {
1417 reloc_root
= root
->reloc_root
;
1418 reloc_root
->last_trans
= trans
->transid
;
1422 if (!rc
|| !rc
->create_reloc_tree
||
1423 root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
)
1426 if (!trans
->reloc_reserved
) {
1427 rsv
= trans
->block_rsv
;
1428 trans
->block_rsv
= rc
->block_rsv
;
1431 reloc_root
= create_reloc_root(trans
, root
, root
->root_key
.objectid
);
1433 trans
->block_rsv
= rsv
;
1435 ret
= __add_reloc_root(reloc_root
);
1437 root
->reloc_root
= reloc_root
;
1442 * update root item of reloc tree
1444 int btrfs_update_reloc_root(struct btrfs_trans_handle
*trans
,
1445 struct btrfs_root
*root
)
1447 struct btrfs_root
*reloc_root
;
1448 struct btrfs_root_item
*root_item
;
1451 if (!root
->reloc_root
)
1454 reloc_root
= root
->reloc_root
;
1455 root_item
= &reloc_root
->root_item
;
1457 if (root
->fs_info
->reloc_ctl
->merge_reloc_tree
&&
1458 btrfs_root_refs(root_item
) == 0) {
1459 root
->reloc_root
= NULL
;
1460 __del_reloc_root(reloc_root
);
1463 if (reloc_root
->commit_root
!= reloc_root
->node
) {
1464 btrfs_set_root_node(root_item
, reloc_root
->node
);
1465 free_extent_buffer(reloc_root
->commit_root
);
1466 reloc_root
->commit_root
= btrfs_root_node(reloc_root
);
1469 ret
= btrfs_update_root(trans
, root
->fs_info
->tree_root
,
1470 &reloc_root
->root_key
, root_item
);
1478 * helper to find first cached inode with inode number >= objectid
1481 static struct inode
*find_next_inode(struct btrfs_root
*root
, u64 objectid
)
1483 struct rb_node
*node
;
1484 struct rb_node
*prev
;
1485 struct btrfs_inode
*entry
;
1486 struct inode
*inode
;
1488 spin_lock(&root
->inode_lock
);
1490 node
= root
->inode_tree
.rb_node
;
1494 entry
= rb_entry(node
, struct btrfs_inode
, rb_node
);
1496 if (objectid
< btrfs_ino(&entry
->vfs_inode
))
1497 node
= node
->rb_left
;
1498 else if (objectid
> btrfs_ino(&entry
->vfs_inode
))
1499 node
= node
->rb_right
;
1505 entry
= rb_entry(prev
, struct btrfs_inode
, rb_node
);
1506 if (objectid
<= btrfs_ino(&entry
->vfs_inode
)) {
1510 prev
= rb_next(prev
);
1514 entry
= rb_entry(node
, struct btrfs_inode
, rb_node
);
1515 inode
= igrab(&entry
->vfs_inode
);
1517 spin_unlock(&root
->inode_lock
);
1521 objectid
= btrfs_ino(&entry
->vfs_inode
) + 1;
1522 if (cond_resched_lock(&root
->inode_lock
))
1525 node
= rb_next(node
);
1527 spin_unlock(&root
->inode_lock
);
1531 static int in_block_group(u64 bytenr
,
1532 struct btrfs_block_group_cache
*block_group
)
1534 if (bytenr
>= block_group
->key
.objectid
&&
1535 bytenr
< block_group
->key
.objectid
+ block_group
->key
.offset
)
1541 * get new location of data
1543 static int get_new_location(struct inode
*reloc_inode
, u64
*new_bytenr
,
1544 u64 bytenr
, u64 num_bytes
)
1546 struct btrfs_root
*root
= BTRFS_I(reloc_inode
)->root
;
1547 struct btrfs_path
*path
;
1548 struct btrfs_file_extent_item
*fi
;
1549 struct extent_buffer
*leaf
;
1552 path
= btrfs_alloc_path();
1556 bytenr
-= BTRFS_I(reloc_inode
)->index_cnt
;
1557 ret
= btrfs_lookup_file_extent(NULL
, root
, path
, btrfs_ino(reloc_inode
),
1566 leaf
= path
->nodes
[0];
1567 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
1568 struct btrfs_file_extent_item
);
1570 BUG_ON(btrfs_file_extent_offset(leaf
, fi
) ||
1571 btrfs_file_extent_compression(leaf
, fi
) ||
1572 btrfs_file_extent_encryption(leaf
, fi
) ||
1573 btrfs_file_extent_other_encoding(leaf
, fi
));
1575 if (num_bytes
!= btrfs_file_extent_disk_num_bytes(leaf
, fi
)) {
1580 *new_bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1583 btrfs_free_path(path
);
1588 * update file extent items in the tree leaf to point to
1589 * the new locations.
1591 static noinline_for_stack
1592 int replace_file_extents(struct btrfs_trans_handle
*trans
,
1593 struct reloc_control
*rc
,
1594 struct btrfs_root
*root
,
1595 struct extent_buffer
*leaf
)
1597 struct btrfs_key key
;
1598 struct btrfs_file_extent_item
*fi
;
1599 struct inode
*inode
= NULL
;
1611 if (rc
->stage
!= UPDATE_DATA_PTRS
)
1614 /* reloc trees always use full backref */
1615 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
)
1616 parent
= leaf
->start
;
1620 nritems
= btrfs_header_nritems(leaf
);
1621 for (i
= 0; i
< nritems
; i
++) {
1623 btrfs_item_key_to_cpu(leaf
, &key
, i
);
1624 if (key
.type
!= BTRFS_EXTENT_DATA_KEY
)
1626 fi
= btrfs_item_ptr(leaf
, i
, struct btrfs_file_extent_item
);
1627 if (btrfs_file_extent_type(leaf
, fi
) ==
1628 BTRFS_FILE_EXTENT_INLINE
)
1630 bytenr
= btrfs_file_extent_disk_bytenr(leaf
, fi
);
1631 num_bytes
= btrfs_file_extent_disk_num_bytes(leaf
, fi
);
1634 if (!in_block_group(bytenr
, rc
->block_group
))
1638 * if we are modifying block in fs tree, wait for readpage
1639 * to complete and drop the extent cache
1641 if (root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
) {
1643 inode
= find_next_inode(root
, key
.objectid
);
1645 } else if (inode
&& btrfs_ino(inode
) < key
.objectid
) {
1646 btrfs_add_delayed_iput(inode
);
1647 inode
= find_next_inode(root
, key
.objectid
);
1649 if (inode
&& btrfs_ino(inode
) == key
.objectid
) {
1651 btrfs_file_extent_num_bytes(leaf
, fi
);
1652 WARN_ON(!IS_ALIGNED(key
.offset
,
1654 WARN_ON(!IS_ALIGNED(end
, root
->sectorsize
));
1656 ret
= try_lock_extent(&BTRFS_I(inode
)->io_tree
,
1661 btrfs_drop_extent_cache(inode
, key
.offset
, end
,
1663 unlock_extent(&BTRFS_I(inode
)->io_tree
,
1668 ret
= get_new_location(rc
->data_inode
, &new_bytenr
,
1672 * Don't have to abort since we've not changed anything
1673 * in the file extent yet.
1678 btrfs_set_file_extent_disk_bytenr(leaf
, fi
, new_bytenr
);
1681 key
.offset
-= btrfs_file_extent_offset(leaf
, fi
);
1682 ret
= btrfs_inc_extent_ref(trans
, root
, new_bytenr
,
1684 btrfs_header_owner(leaf
),
1685 key
.objectid
, key
.offset
, 1);
1687 btrfs_abort_transaction(trans
, root
, ret
);
1691 ret
= btrfs_free_extent(trans
, root
, bytenr
, num_bytes
,
1692 parent
, btrfs_header_owner(leaf
),
1693 key
.objectid
, key
.offset
, 1);
1695 btrfs_abort_transaction(trans
, root
, ret
);
1700 btrfs_mark_buffer_dirty(leaf
);
1702 btrfs_add_delayed_iput(inode
);
1706 static noinline_for_stack
1707 int memcmp_node_keys(struct extent_buffer
*eb
, int slot
,
1708 struct btrfs_path
*path
, int level
)
1710 struct btrfs_disk_key key1
;
1711 struct btrfs_disk_key key2
;
1712 btrfs_node_key(eb
, &key1
, slot
);
1713 btrfs_node_key(path
->nodes
[level
], &key2
, path
->slots
[level
]);
1714 return memcmp(&key1
, &key2
, sizeof(key1
));
1718 * try to replace tree blocks in fs tree with the new blocks
1719 * in reloc tree. tree blocks haven't been modified since the
1720 * reloc tree was create can be replaced.
1722 * if a block was replaced, level of the block + 1 is returned.
1723 * if no block got replaced, 0 is returned. if there are other
1724 * errors, a negative error number is returned.
1726 static noinline_for_stack
1727 int replace_path(struct btrfs_trans_handle
*trans
,
1728 struct btrfs_root
*dest
, struct btrfs_root
*src
,
1729 struct btrfs_path
*path
, struct btrfs_key
*next_key
,
1730 int lowest_level
, int max_level
)
1732 struct extent_buffer
*eb
;
1733 struct extent_buffer
*parent
;
1734 struct btrfs_key key
;
1746 BUG_ON(src
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
);
1747 BUG_ON(dest
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
);
1749 last_snapshot
= btrfs_root_last_snapshot(&src
->root_item
);
1751 slot
= path
->slots
[lowest_level
];
1752 btrfs_node_key_to_cpu(path
->nodes
[lowest_level
], &key
, slot
);
1754 eb
= btrfs_lock_root_node(dest
);
1755 btrfs_set_lock_blocking(eb
);
1756 level
= btrfs_header_level(eb
);
1758 if (level
< lowest_level
) {
1759 btrfs_tree_unlock(eb
);
1760 free_extent_buffer(eb
);
1765 ret
= btrfs_cow_block(trans
, dest
, eb
, NULL
, 0, &eb
);
1768 btrfs_set_lock_blocking(eb
);
1771 next_key
->objectid
= (u64
)-1;
1772 next_key
->type
= (u8
)-1;
1773 next_key
->offset
= (u64
)-1;
1778 level
= btrfs_header_level(parent
);
1779 BUG_ON(level
< lowest_level
);
1781 ret
= btrfs_bin_search(parent
, &key
, level
, &slot
);
1782 if (ret
&& slot
> 0)
1785 if (next_key
&& slot
+ 1 < btrfs_header_nritems(parent
))
1786 btrfs_node_key_to_cpu(parent
, next_key
, slot
+ 1);
1788 old_bytenr
= btrfs_node_blockptr(parent
, slot
);
1789 blocksize
= btrfs_level_size(dest
, level
- 1);
1790 old_ptr_gen
= btrfs_node_ptr_generation(parent
, slot
);
1792 if (level
<= max_level
) {
1793 eb
= path
->nodes
[level
];
1794 new_bytenr
= btrfs_node_blockptr(eb
,
1795 path
->slots
[level
]);
1796 new_ptr_gen
= btrfs_node_ptr_generation(eb
,
1797 path
->slots
[level
]);
1803 if (WARN_ON(new_bytenr
> 0 && new_bytenr
== old_bytenr
)) {
1808 if (new_bytenr
== 0 || old_ptr_gen
> last_snapshot
||
1809 memcmp_node_keys(parent
, slot
, path
, level
)) {
1810 if (level
<= lowest_level
) {
1815 eb
= read_tree_block(dest
, old_bytenr
, blocksize
,
1817 if (!eb
|| !extent_buffer_uptodate(eb
)) {
1818 ret
= (!eb
) ? -ENOMEM
: -EIO
;
1819 free_extent_buffer(eb
);
1822 btrfs_tree_lock(eb
);
1824 ret
= btrfs_cow_block(trans
, dest
, eb
, parent
,
1828 btrfs_set_lock_blocking(eb
);
1830 btrfs_tree_unlock(parent
);
1831 free_extent_buffer(parent
);
1838 btrfs_tree_unlock(parent
);
1839 free_extent_buffer(parent
);
1844 btrfs_node_key_to_cpu(path
->nodes
[level
], &key
,
1845 path
->slots
[level
]);
1846 btrfs_release_path(path
);
1848 path
->lowest_level
= level
;
1849 ret
= btrfs_search_slot(trans
, src
, &key
, path
, 0, 1);
1850 path
->lowest_level
= 0;
1854 * swap blocks in fs tree and reloc tree.
1856 btrfs_set_node_blockptr(parent
, slot
, new_bytenr
);
1857 btrfs_set_node_ptr_generation(parent
, slot
, new_ptr_gen
);
1858 btrfs_mark_buffer_dirty(parent
);
1860 btrfs_set_node_blockptr(path
->nodes
[level
],
1861 path
->slots
[level
], old_bytenr
);
1862 btrfs_set_node_ptr_generation(path
->nodes
[level
],
1863 path
->slots
[level
], old_ptr_gen
);
1864 btrfs_mark_buffer_dirty(path
->nodes
[level
]);
1866 ret
= btrfs_inc_extent_ref(trans
, src
, old_bytenr
, blocksize
,
1867 path
->nodes
[level
]->start
,
1868 src
->root_key
.objectid
, level
- 1, 0,
1871 ret
= btrfs_inc_extent_ref(trans
, dest
, new_bytenr
, blocksize
,
1872 0, dest
->root_key
.objectid
, level
- 1,
1876 ret
= btrfs_free_extent(trans
, src
, new_bytenr
, blocksize
,
1877 path
->nodes
[level
]->start
,
1878 src
->root_key
.objectid
, level
- 1, 0,
1882 ret
= btrfs_free_extent(trans
, dest
, old_bytenr
, blocksize
,
1883 0, dest
->root_key
.objectid
, level
- 1,
1887 btrfs_unlock_up_safe(path
, 0);
1892 btrfs_tree_unlock(parent
);
1893 free_extent_buffer(parent
);
1898 * helper to find next relocated block in reloc tree
1900 static noinline_for_stack
1901 int walk_up_reloc_tree(struct btrfs_root
*root
, struct btrfs_path
*path
,
1904 struct extent_buffer
*eb
;
1909 last_snapshot
= btrfs_root_last_snapshot(&root
->root_item
);
1911 for (i
= 0; i
< *level
; i
++) {
1912 free_extent_buffer(path
->nodes
[i
]);
1913 path
->nodes
[i
] = NULL
;
1916 for (i
= *level
; i
< BTRFS_MAX_LEVEL
&& path
->nodes
[i
]; i
++) {
1917 eb
= path
->nodes
[i
];
1918 nritems
= btrfs_header_nritems(eb
);
1919 while (path
->slots
[i
] + 1 < nritems
) {
1921 if (btrfs_node_ptr_generation(eb
, path
->slots
[i
]) <=
1928 free_extent_buffer(path
->nodes
[i
]);
1929 path
->nodes
[i
] = NULL
;
1935 * walk down reloc tree to find relocated block of lowest level
1937 static noinline_for_stack
1938 int walk_down_reloc_tree(struct btrfs_root
*root
, struct btrfs_path
*path
,
1941 struct extent_buffer
*eb
= NULL
;
1949 last_snapshot
= btrfs_root_last_snapshot(&root
->root_item
);
1951 for (i
= *level
; i
> 0; i
--) {
1952 eb
= path
->nodes
[i
];
1953 nritems
= btrfs_header_nritems(eb
);
1954 while (path
->slots
[i
] < nritems
) {
1955 ptr_gen
= btrfs_node_ptr_generation(eb
, path
->slots
[i
]);
1956 if (ptr_gen
> last_snapshot
)
1960 if (path
->slots
[i
] >= nritems
) {
1971 bytenr
= btrfs_node_blockptr(eb
, path
->slots
[i
]);
1972 blocksize
= btrfs_level_size(root
, i
- 1);
1973 eb
= read_tree_block(root
, bytenr
, blocksize
, ptr_gen
);
1974 if (!eb
|| !extent_buffer_uptodate(eb
)) {
1975 free_extent_buffer(eb
);
1978 BUG_ON(btrfs_header_level(eb
) != i
- 1);
1979 path
->nodes
[i
- 1] = eb
;
1980 path
->slots
[i
- 1] = 0;
1986 * invalidate extent cache for file extents whose key in range of
1987 * [min_key, max_key)
1989 static int invalidate_extent_cache(struct btrfs_root
*root
,
1990 struct btrfs_key
*min_key
,
1991 struct btrfs_key
*max_key
)
1993 struct inode
*inode
= NULL
;
1998 objectid
= min_key
->objectid
;
2003 if (objectid
> max_key
->objectid
)
2006 inode
= find_next_inode(root
, objectid
);
2009 ino
= btrfs_ino(inode
);
2011 if (ino
> max_key
->objectid
) {
2017 if (!S_ISREG(inode
->i_mode
))
2020 if (unlikely(min_key
->objectid
== ino
)) {
2021 if (min_key
->type
> BTRFS_EXTENT_DATA_KEY
)
2023 if (min_key
->type
< BTRFS_EXTENT_DATA_KEY
)
2026 start
= min_key
->offset
;
2027 WARN_ON(!IS_ALIGNED(start
, root
->sectorsize
));
2033 if (unlikely(max_key
->objectid
== ino
)) {
2034 if (max_key
->type
< BTRFS_EXTENT_DATA_KEY
)
2036 if (max_key
->type
> BTRFS_EXTENT_DATA_KEY
) {
2039 if (max_key
->offset
== 0)
2041 end
= max_key
->offset
;
2042 WARN_ON(!IS_ALIGNED(end
, root
->sectorsize
));
2049 /* the lock_extent waits for readpage to complete */
2050 lock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
2051 btrfs_drop_extent_cache(inode
, start
, end
, 1);
2052 unlock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
2057 static int find_next_key(struct btrfs_path
*path
, int level
,
2058 struct btrfs_key
*key
)
2061 while (level
< BTRFS_MAX_LEVEL
) {
2062 if (!path
->nodes
[level
])
2064 if (path
->slots
[level
] + 1 <
2065 btrfs_header_nritems(path
->nodes
[level
])) {
2066 btrfs_node_key_to_cpu(path
->nodes
[level
], key
,
2067 path
->slots
[level
] + 1);
2076 * merge the relocated tree blocks in reloc tree with corresponding
2079 static noinline_for_stack
int merge_reloc_root(struct reloc_control
*rc
,
2080 struct btrfs_root
*root
)
2082 LIST_HEAD(inode_list
);
2083 struct btrfs_key key
;
2084 struct btrfs_key next_key
;
2085 struct btrfs_trans_handle
*trans
= NULL
;
2086 struct btrfs_root
*reloc_root
;
2087 struct btrfs_root_item
*root_item
;
2088 struct btrfs_path
*path
;
2089 struct extent_buffer
*leaf
;
2097 path
= btrfs_alloc_path();
2102 reloc_root
= root
->reloc_root
;
2103 root_item
= &reloc_root
->root_item
;
2105 if (btrfs_disk_key_objectid(&root_item
->drop_progress
) == 0) {
2106 level
= btrfs_root_level(root_item
);
2107 extent_buffer_get(reloc_root
->node
);
2108 path
->nodes
[level
] = reloc_root
->node
;
2109 path
->slots
[level
] = 0;
2111 btrfs_disk_key_to_cpu(&key
, &root_item
->drop_progress
);
2113 level
= root_item
->drop_level
;
2115 path
->lowest_level
= level
;
2116 ret
= btrfs_search_slot(NULL
, reloc_root
, &key
, path
, 0, 0);
2117 path
->lowest_level
= 0;
2119 btrfs_free_path(path
);
2123 btrfs_node_key_to_cpu(path
->nodes
[level
], &next_key
,
2124 path
->slots
[level
]);
2125 WARN_ON(memcmp(&key
, &next_key
, sizeof(key
)));
2127 btrfs_unlock_up_safe(path
, 0);
2130 min_reserved
= root
->nodesize
* (BTRFS_MAX_LEVEL
- 1) * 2;
2131 memset(&next_key
, 0, sizeof(next_key
));
2134 ret
= btrfs_block_rsv_refill(root
, rc
->block_rsv
, min_reserved
,
2135 BTRFS_RESERVE_FLUSH_ALL
);
2140 trans
= btrfs_start_transaction(root
, 0);
2141 if (IS_ERR(trans
)) {
2142 err
= PTR_ERR(trans
);
2146 trans
->block_rsv
= rc
->block_rsv
;
2151 ret
= walk_down_reloc_tree(reloc_root
, path
, &level
);
2159 if (!find_next_key(path
, level
, &key
) &&
2160 btrfs_comp_cpu_keys(&next_key
, &key
) >= 0) {
2163 ret
= replace_path(trans
, root
, reloc_root
, path
,
2164 &next_key
, level
, max_level
);
2173 btrfs_node_key_to_cpu(path
->nodes
[level
], &key
,
2174 path
->slots
[level
]);
2178 ret
= walk_up_reloc_tree(reloc_root
, path
, &level
);
2184 * save the merging progress in the drop_progress.
2185 * this is OK since root refs == 1 in this case.
2187 btrfs_node_key(path
->nodes
[level
], &root_item
->drop_progress
,
2188 path
->slots
[level
]);
2189 root_item
->drop_level
= level
;
2191 btrfs_end_transaction_throttle(trans
, root
);
2194 btrfs_btree_balance_dirty(root
);
2196 if (replaced
&& rc
->stage
== UPDATE_DATA_PTRS
)
2197 invalidate_extent_cache(root
, &key
, &next_key
);
2201 * handle the case only one block in the fs tree need to be
2202 * relocated and the block is tree root.
2204 leaf
= btrfs_lock_root_node(root
);
2205 ret
= btrfs_cow_block(trans
, root
, leaf
, NULL
, 0, &leaf
);
2206 btrfs_tree_unlock(leaf
);
2207 free_extent_buffer(leaf
);
2211 btrfs_free_path(path
);
2214 memset(&root_item
->drop_progress
, 0,
2215 sizeof(root_item
->drop_progress
));
2216 root_item
->drop_level
= 0;
2217 btrfs_set_root_refs(root_item
, 0);
2218 btrfs_update_reloc_root(trans
, root
);
2222 btrfs_end_transaction_throttle(trans
, root
);
2224 btrfs_btree_balance_dirty(root
);
2226 if (replaced
&& rc
->stage
== UPDATE_DATA_PTRS
)
2227 invalidate_extent_cache(root
, &key
, &next_key
);
2232 static noinline_for_stack
2233 int prepare_to_merge(struct reloc_control
*rc
, int err
)
2235 struct btrfs_root
*root
= rc
->extent_root
;
2236 struct btrfs_root
*reloc_root
;
2237 struct btrfs_trans_handle
*trans
;
2238 LIST_HEAD(reloc_roots
);
2242 mutex_lock(&root
->fs_info
->reloc_mutex
);
2243 rc
->merging_rsv_size
+= root
->nodesize
* (BTRFS_MAX_LEVEL
- 1) * 2;
2244 rc
->merging_rsv_size
+= rc
->nodes_relocated
* 2;
2245 mutex_unlock(&root
->fs_info
->reloc_mutex
);
2249 num_bytes
= rc
->merging_rsv_size
;
2250 ret
= btrfs_block_rsv_add(root
, rc
->block_rsv
, num_bytes
,
2251 BTRFS_RESERVE_FLUSH_ALL
);
2256 trans
= btrfs_join_transaction(rc
->extent_root
);
2257 if (IS_ERR(trans
)) {
2259 btrfs_block_rsv_release(rc
->extent_root
,
2260 rc
->block_rsv
, num_bytes
);
2261 return PTR_ERR(trans
);
2265 if (num_bytes
!= rc
->merging_rsv_size
) {
2266 btrfs_end_transaction(trans
, rc
->extent_root
);
2267 btrfs_block_rsv_release(rc
->extent_root
,
2268 rc
->block_rsv
, num_bytes
);
2273 rc
->merge_reloc_tree
= 1;
2275 while (!list_empty(&rc
->reloc_roots
)) {
2276 reloc_root
= list_entry(rc
->reloc_roots
.next
,
2277 struct btrfs_root
, root_list
);
2278 list_del_init(&reloc_root
->root_list
);
2280 root
= read_fs_root(reloc_root
->fs_info
,
2281 reloc_root
->root_key
.offset
);
2282 BUG_ON(IS_ERR(root
));
2283 BUG_ON(root
->reloc_root
!= reloc_root
);
2286 * set reference count to 1, so btrfs_recover_relocation
2287 * knows it should resumes merging
2290 btrfs_set_root_refs(&reloc_root
->root_item
, 1);
2291 btrfs_update_reloc_root(trans
, root
);
2293 list_add(&reloc_root
->root_list
, &reloc_roots
);
2296 list_splice(&reloc_roots
, &rc
->reloc_roots
);
2299 btrfs_commit_transaction(trans
, rc
->extent_root
);
2301 btrfs_end_transaction(trans
, rc
->extent_root
);
2305 static noinline_for_stack
2306 void free_reloc_roots(struct list_head
*list
)
2308 struct btrfs_root
*reloc_root
;
2310 while (!list_empty(list
)) {
2311 reloc_root
= list_entry(list
->next
, struct btrfs_root
,
2313 __del_reloc_root(reloc_root
);
2317 static noinline_for_stack
2318 int merge_reloc_roots(struct reloc_control
*rc
)
2320 struct btrfs_root
*root
;
2321 struct btrfs_root
*reloc_root
;
2325 LIST_HEAD(reloc_roots
);
2329 root
= rc
->extent_root
;
2332 * this serializes us with btrfs_record_root_in_transaction,
2333 * we have to make sure nobody is in the middle of
2334 * adding their roots to the list while we are
2337 mutex_lock(&root
->fs_info
->reloc_mutex
);
2338 list_splice_init(&rc
->reloc_roots
, &reloc_roots
);
2339 mutex_unlock(&root
->fs_info
->reloc_mutex
);
2341 while (!list_empty(&reloc_roots
)) {
2343 reloc_root
= list_entry(reloc_roots
.next
,
2344 struct btrfs_root
, root_list
);
2346 if (btrfs_root_refs(&reloc_root
->root_item
) > 0) {
2347 root
= read_fs_root(reloc_root
->fs_info
,
2348 reloc_root
->root_key
.offset
);
2349 BUG_ON(IS_ERR(root
));
2350 BUG_ON(root
->reloc_root
!= reloc_root
);
2352 ret
= merge_reloc_root(rc
, root
);
2354 if (list_empty(&reloc_root
->root_list
))
2355 list_add_tail(&reloc_root
->root_list
,
2360 list_del_init(&reloc_root
->root_list
);
2364 * we keep the old last snapshod transid in rtranid when we
2365 * created the relocation tree.
2367 last_snap
= btrfs_root_rtransid(&reloc_root
->root_item
);
2368 otransid
= btrfs_root_otransid(&reloc_root
->root_item
);
2369 objectid
= reloc_root
->root_key
.offset
;
2371 ret
= btrfs_drop_snapshot(reloc_root
, rc
->block_rsv
, 0, 1);
2373 if (list_empty(&reloc_root
->root_list
))
2374 list_add_tail(&reloc_root
->root_list
,
2386 btrfs_std_error(root
->fs_info
, ret
);
2387 if (!list_empty(&reloc_roots
))
2388 free_reloc_roots(&reloc_roots
);
2390 /* new reloc root may be added */
2391 mutex_lock(&root
->fs_info
->reloc_mutex
);
2392 list_splice_init(&rc
->reloc_roots
, &reloc_roots
);
2393 mutex_unlock(&root
->fs_info
->reloc_mutex
);
2394 if (!list_empty(&reloc_roots
))
2395 free_reloc_roots(&reloc_roots
);
2398 BUG_ON(!RB_EMPTY_ROOT(&rc
->reloc_root_tree
.rb_root
));
2402 static void free_block_list(struct rb_root
*blocks
)
2404 struct tree_block
*block
;
2405 struct rb_node
*rb_node
;
2406 while ((rb_node
= rb_first(blocks
))) {
2407 block
= rb_entry(rb_node
, struct tree_block
, rb_node
);
2408 rb_erase(rb_node
, blocks
);
2413 static int record_reloc_root_in_trans(struct btrfs_trans_handle
*trans
,
2414 struct btrfs_root
*reloc_root
)
2416 struct btrfs_root
*root
;
2418 if (reloc_root
->last_trans
== trans
->transid
)
2421 root
= read_fs_root(reloc_root
->fs_info
, reloc_root
->root_key
.offset
);
2422 BUG_ON(IS_ERR(root
));
2423 BUG_ON(root
->reloc_root
!= reloc_root
);
2425 return btrfs_record_root_in_trans(trans
, root
);
2428 static noinline_for_stack
2429 struct btrfs_root
*select_reloc_root(struct btrfs_trans_handle
*trans
,
2430 struct reloc_control
*rc
,
2431 struct backref_node
*node
,
2432 struct backref_edge
*edges
[])
2434 struct backref_node
*next
;
2435 struct btrfs_root
*root
;
2441 next
= walk_up_backref(next
, edges
, &index
);
2444 BUG_ON(!root
->ref_cows
);
2446 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
) {
2447 record_reloc_root_in_trans(trans
, root
);
2451 btrfs_record_root_in_trans(trans
, root
);
2452 root
= root
->reloc_root
;
2454 if (next
->new_bytenr
!= root
->node
->start
) {
2455 BUG_ON(next
->new_bytenr
);
2456 BUG_ON(!list_empty(&next
->list
));
2457 next
->new_bytenr
= root
->node
->start
;
2459 list_add_tail(&next
->list
,
2460 &rc
->backref_cache
.changed
);
2461 __mark_block_processed(rc
, next
);
2467 next
= walk_down_backref(edges
, &index
);
2468 if (!next
|| next
->level
<= node
->level
)
2475 /* setup backref node path for btrfs_reloc_cow_block */
2477 rc
->backref_cache
.path
[next
->level
] = next
;
2480 next
= edges
[index
]->node
[UPPER
];
2486 * select a tree root for relocation. return NULL if the block
2487 * is reference counted. we should use do_relocation() in this
2488 * case. return a tree root pointer if the block isn't reference
2489 * counted. return -ENOENT if the block is root of reloc tree.
2491 static noinline_for_stack
2492 struct btrfs_root
*select_one_root(struct btrfs_trans_handle
*trans
,
2493 struct backref_node
*node
)
2495 struct backref_node
*next
;
2496 struct btrfs_root
*root
;
2497 struct btrfs_root
*fs_root
= NULL
;
2498 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2504 next
= walk_up_backref(next
, edges
, &index
);
2508 /* no other choice for non-references counted tree */
2509 if (!root
->ref_cows
)
2512 if (root
->root_key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
)
2518 next
= walk_down_backref(edges
, &index
);
2519 if (!next
|| next
->level
<= node
->level
)
2524 return ERR_PTR(-ENOENT
);
2528 static noinline_for_stack
2529 u64
calcu_metadata_size(struct reloc_control
*rc
,
2530 struct backref_node
*node
, int reserve
)
2532 struct backref_node
*next
= node
;
2533 struct backref_edge
*edge
;
2534 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2538 BUG_ON(reserve
&& node
->processed
);
2543 if (next
->processed
&& (reserve
|| next
!= node
))
2546 num_bytes
+= btrfs_level_size(rc
->extent_root
,
2549 if (list_empty(&next
->upper
))
2552 edge
= list_entry(next
->upper
.next
,
2553 struct backref_edge
, list
[LOWER
]);
2554 edges
[index
++] = edge
;
2555 next
= edge
->node
[UPPER
];
2557 next
= walk_down_backref(edges
, &index
);
2562 static int reserve_metadata_space(struct btrfs_trans_handle
*trans
,
2563 struct reloc_control
*rc
,
2564 struct backref_node
*node
)
2566 struct btrfs_root
*root
= rc
->extent_root
;
2571 num_bytes
= calcu_metadata_size(rc
, node
, 1) * 2;
2573 trans
->block_rsv
= rc
->block_rsv
;
2574 rc
->reserved_bytes
+= num_bytes
;
2575 ret
= btrfs_block_rsv_refill(root
, rc
->block_rsv
, num_bytes
,
2576 BTRFS_RESERVE_FLUSH_ALL
);
2578 if (ret
== -EAGAIN
) {
2579 tmp
= rc
->extent_root
->nodesize
*
2580 RELOCATION_RESERVED_NODES
;
2581 while (tmp
<= rc
->reserved_bytes
)
2584 * only one thread can access block_rsv at this point,
2585 * so we don't need hold lock to protect block_rsv.
2586 * we expand more reservation size here to allow enough
2587 * space for relocation and we will return eailer in
2590 rc
->block_rsv
->size
= tmp
+ rc
->extent_root
->nodesize
*
2591 RELOCATION_RESERVED_NODES
;
2600 * relocate a block tree, and then update pointers in upper level
2601 * blocks that reference the block to point to the new location.
2603 * if called by link_to_upper, the block has already been relocated.
2604 * in that case this function just updates pointers.
2606 static int do_relocation(struct btrfs_trans_handle
*trans
,
2607 struct reloc_control
*rc
,
2608 struct backref_node
*node
,
2609 struct btrfs_key
*key
,
2610 struct btrfs_path
*path
, int lowest
)
2612 struct backref_node
*upper
;
2613 struct backref_edge
*edge
;
2614 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2615 struct btrfs_root
*root
;
2616 struct extent_buffer
*eb
;
2624 BUG_ON(lowest
&& node
->eb
);
2626 path
->lowest_level
= node
->level
+ 1;
2627 rc
->backref_cache
.path
[node
->level
] = node
;
2628 list_for_each_entry(edge
, &node
->upper
, list
[LOWER
]) {
2631 upper
= edge
->node
[UPPER
];
2632 root
= select_reloc_root(trans
, rc
, upper
, edges
);
2635 if (upper
->eb
&& !upper
->locked
) {
2637 ret
= btrfs_bin_search(upper
->eb
, key
,
2638 upper
->level
, &slot
);
2640 bytenr
= btrfs_node_blockptr(upper
->eb
, slot
);
2641 if (node
->eb
->start
== bytenr
)
2644 drop_node_buffer(upper
);
2648 ret
= btrfs_search_slot(trans
, root
, key
, path
, 0, 1);
2656 upper
->eb
= path
->nodes
[upper
->level
];
2657 path
->nodes
[upper
->level
] = NULL
;
2659 BUG_ON(upper
->eb
!= path
->nodes
[upper
->level
]);
2663 path
->locks
[upper
->level
] = 0;
2665 slot
= path
->slots
[upper
->level
];
2666 btrfs_release_path(path
);
2668 ret
= btrfs_bin_search(upper
->eb
, key
, upper
->level
,
2673 bytenr
= btrfs_node_blockptr(upper
->eb
, slot
);
2675 BUG_ON(bytenr
!= node
->bytenr
);
2677 if (node
->eb
->start
== bytenr
)
2681 blocksize
= btrfs_level_size(root
, node
->level
);
2682 generation
= btrfs_node_ptr_generation(upper
->eb
, slot
);
2683 eb
= read_tree_block(root
, bytenr
, blocksize
, generation
);
2684 if (!eb
|| !extent_buffer_uptodate(eb
)) {
2685 free_extent_buffer(eb
);
2689 btrfs_tree_lock(eb
);
2690 btrfs_set_lock_blocking(eb
);
2693 ret
= btrfs_cow_block(trans
, root
, eb
, upper
->eb
,
2695 btrfs_tree_unlock(eb
);
2696 free_extent_buffer(eb
);
2701 BUG_ON(node
->eb
!= eb
);
2703 btrfs_set_node_blockptr(upper
->eb
, slot
,
2705 btrfs_set_node_ptr_generation(upper
->eb
, slot
,
2707 btrfs_mark_buffer_dirty(upper
->eb
);
2709 ret
= btrfs_inc_extent_ref(trans
, root
,
2710 node
->eb
->start
, blocksize
,
2712 btrfs_header_owner(upper
->eb
),
2716 ret
= btrfs_drop_subtree(trans
, root
, eb
, upper
->eb
);
2720 if (!upper
->pending
)
2721 drop_node_buffer(upper
);
2723 unlock_node_buffer(upper
);
2728 if (!err
&& node
->pending
) {
2729 drop_node_buffer(node
);
2730 list_move_tail(&node
->list
, &rc
->backref_cache
.changed
);
2734 path
->lowest_level
= 0;
2735 BUG_ON(err
== -ENOSPC
);
2739 static int link_to_upper(struct btrfs_trans_handle
*trans
,
2740 struct reloc_control
*rc
,
2741 struct backref_node
*node
,
2742 struct btrfs_path
*path
)
2744 struct btrfs_key key
;
2746 btrfs_node_key_to_cpu(node
->eb
, &key
, 0);
2747 return do_relocation(trans
, rc
, node
, &key
, path
, 0);
2750 static int finish_pending_nodes(struct btrfs_trans_handle
*trans
,
2751 struct reloc_control
*rc
,
2752 struct btrfs_path
*path
, int err
)
2755 struct backref_cache
*cache
= &rc
->backref_cache
;
2756 struct backref_node
*node
;
2760 for (level
= 0; level
< BTRFS_MAX_LEVEL
; level
++) {
2761 while (!list_empty(&cache
->pending
[level
])) {
2762 node
= list_entry(cache
->pending
[level
].next
,
2763 struct backref_node
, list
);
2764 list_move_tail(&node
->list
, &list
);
2765 BUG_ON(!node
->pending
);
2768 ret
= link_to_upper(trans
, rc
, node
, path
);
2773 list_splice_init(&list
, &cache
->pending
[level
]);
2778 static void mark_block_processed(struct reloc_control
*rc
,
2779 u64 bytenr
, u32 blocksize
)
2781 set_extent_bits(&rc
->processed_blocks
, bytenr
, bytenr
+ blocksize
- 1,
2782 EXTENT_DIRTY
, GFP_NOFS
);
2785 static void __mark_block_processed(struct reloc_control
*rc
,
2786 struct backref_node
*node
)
2789 if (node
->level
== 0 ||
2790 in_block_group(node
->bytenr
, rc
->block_group
)) {
2791 blocksize
= btrfs_level_size(rc
->extent_root
, node
->level
);
2792 mark_block_processed(rc
, node
->bytenr
, blocksize
);
2794 node
->processed
= 1;
2798 * mark a block and all blocks directly/indirectly reference the block
2801 static void update_processed_blocks(struct reloc_control
*rc
,
2802 struct backref_node
*node
)
2804 struct backref_node
*next
= node
;
2805 struct backref_edge
*edge
;
2806 struct backref_edge
*edges
[BTRFS_MAX_LEVEL
- 1];
2812 if (next
->processed
)
2815 __mark_block_processed(rc
, next
);
2817 if (list_empty(&next
->upper
))
2820 edge
= list_entry(next
->upper
.next
,
2821 struct backref_edge
, list
[LOWER
]);
2822 edges
[index
++] = edge
;
2823 next
= edge
->node
[UPPER
];
2825 next
= walk_down_backref(edges
, &index
);
2829 static int tree_block_processed(u64 bytenr
, u32 blocksize
,
2830 struct reloc_control
*rc
)
2832 if (test_range_bit(&rc
->processed_blocks
, bytenr
,
2833 bytenr
+ blocksize
- 1, EXTENT_DIRTY
, 1, NULL
))
2838 static int get_tree_block_key(struct reloc_control
*rc
,
2839 struct tree_block
*block
)
2841 struct extent_buffer
*eb
;
2843 BUG_ON(block
->key_ready
);
2844 eb
= read_tree_block(rc
->extent_root
, block
->bytenr
,
2845 block
->key
.objectid
, block
->key
.offset
);
2846 if (!eb
|| !extent_buffer_uptodate(eb
)) {
2847 free_extent_buffer(eb
);
2850 WARN_ON(btrfs_header_level(eb
) != block
->level
);
2851 if (block
->level
== 0)
2852 btrfs_item_key_to_cpu(eb
, &block
->key
, 0);
2854 btrfs_node_key_to_cpu(eb
, &block
->key
, 0);
2855 free_extent_buffer(eb
);
2856 block
->key_ready
= 1;
2860 static int reada_tree_block(struct reloc_control
*rc
,
2861 struct tree_block
*block
)
2863 BUG_ON(block
->key_ready
);
2864 if (block
->key
.type
== BTRFS_METADATA_ITEM_KEY
)
2865 readahead_tree_block(rc
->extent_root
, block
->bytenr
,
2866 block
->key
.objectid
,
2867 rc
->extent_root
->leafsize
);
2869 readahead_tree_block(rc
->extent_root
, block
->bytenr
,
2870 block
->key
.objectid
, block
->key
.offset
);
2875 * helper function to relocate a tree block
2877 static int relocate_tree_block(struct btrfs_trans_handle
*trans
,
2878 struct reloc_control
*rc
,
2879 struct backref_node
*node
,
2880 struct btrfs_key
*key
,
2881 struct btrfs_path
*path
)
2883 struct btrfs_root
*root
;
2889 BUG_ON(node
->processed
);
2890 root
= select_one_root(trans
, node
);
2891 if (root
== ERR_PTR(-ENOENT
)) {
2892 update_processed_blocks(rc
, node
);
2896 if (!root
|| root
->ref_cows
) {
2897 ret
= reserve_metadata_space(trans
, rc
, node
);
2903 if (root
->ref_cows
) {
2904 BUG_ON(node
->new_bytenr
);
2905 BUG_ON(!list_empty(&node
->list
));
2906 btrfs_record_root_in_trans(trans
, root
);
2907 root
= root
->reloc_root
;
2908 node
->new_bytenr
= root
->node
->start
;
2910 list_add_tail(&node
->list
, &rc
->backref_cache
.changed
);
2912 path
->lowest_level
= node
->level
;
2913 ret
= btrfs_search_slot(trans
, root
, key
, path
, 0, 1);
2914 btrfs_release_path(path
);
2919 update_processed_blocks(rc
, node
);
2921 ret
= do_relocation(trans
, rc
, node
, key
, path
, 1);
2924 if (ret
|| node
->level
== 0 || node
->cowonly
)
2925 remove_backref_node(&rc
->backref_cache
, node
);
2930 * relocate a list of blocks
2932 static noinline_for_stack
2933 int relocate_tree_blocks(struct btrfs_trans_handle
*trans
,
2934 struct reloc_control
*rc
, struct rb_root
*blocks
)
2936 struct backref_node
*node
;
2937 struct btrfs_path
*path
;
2938 struct tree_block
*block
;
2939 struct rb_node
*rb_node
;
2943 path
= btrfs_alloc_path();
2946 goto out_free_blocks
;
2949 rb_node
= rb_first(blocks
);
2951 block
= rb_entry(rb_node
, struct tree_block
, rb_node
);
2952 if (!block
->key_ready
)
2953 reada_tree_block(rc
, block
);
2954 rb_node
= rb_next(rb_node
);
2957 rb_node
= rb_first(blocks
);
2959 block
= rb_entry(rb_node
, struct tree_block
, rb_node
);
2960 if (!block
->key_ready
) {
2961 err
= get_tree_block_key(rc
, block
);
2965 rb_node
= rb_next(rb_node
);
2968 rb_node
= rb_first(blocks
);
2970 block
= rb_entry(rb_node
, struct tree_block
, rb_node
);
2972 node
= build_backref_tree(rc
, &block
->key
,
2973 block
->level
, block
->bytenr
);
2975 err
= PTR_ERR(node
);
2979 ret
= relocate_tree_block(trans
, rc
, node
, &block
->key
,
2982 if (ret
!= -EAGAIN
|| rb_node
== rb_first(blocks
))
2986 rb_node
= rb_next(rb_node
);
2989 err
= finish_pending_nodes(trans
, rc
, path
, err
);
2992 btrfs_free_path(path
);
2994 free_block_list(blocks
);
2998 static noinline_for_stack
2999 int prealloc_file_extent_cluster(struct inode
*inode
,
3000 struct file_extent_cluster
*cluster
)
3005 u64 offset
= BTRFS_I(inode
)->index_cnt
;
3010 BUG_ON(cluster
->start
!= cluster
->boundary
[0]);
3011 mutex_lock(&inode
->i_mutex
);
3013 ret
= btrfs_check_data_free_space(inode
, cluster
->end
+
3014 1 - cluster
->start
);
3018 while (nr
< cluster
->nr
) {
3019 start
= cluster
->boundary
[nr
] - offset
;
3020 if (nr
+ 1 < cluster
->nr
)
3021 end
= cluster
->boundary
[nr
+ 1] - 1 - offset
;
3023 end
= cluster
->end
- offset
;
3025 lock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
3026 num_bytes
= end
+ 1 - start
;
3027 ret
= btrfs_prealloc_file_range(inode
, 0, start
,
3028 num_bytes
, num_bytes
,
3029 end
+ 1, &alloc_hint
);
3030 unlock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
3035 btrfs_free_reserved_data_space(inode
, cluster
->end
+
3036 1 - cluster
->start
);
3038 mutex_unlock(&inode
->i_mutex
);
3042 static noinline_for_stack
3043 int setup_extent_mapping(struct inode
*inode
, u64 start
, u64 end
,
3046 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
3047 struct extent_map_tree
*em_tree
= &BTRFS_I(inode
)->extent_tree
;
3048 struct extent_map
*em
;
3051 em
= alloc_extent_map();
3056 em
->len
= end
+ 1 - start
;
3057 em
->block_len
= em
->len
;
3058 em
->block_start
= block_start
;
3059 em
->bdev
= root
->fs_info
->fs_devices
->latest_bdev
;
3060 set_bit(EXTENT_FLAG_PINNED
, &em
->flags
);
3062 lock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
3064 write_lock(&em_tree
->lock
);
3065 ret
= add_extent_mapping(em_tree
, em
, 0);
3066 write_unlock(&em_tree
->lock
);
3067 if (ret
!= -EEXIST
) {
3068 free_extent_map(em
);
3071 btrfs_drop_extent_cache(inode
, start
, end
, 0);
3073 unlock_extent(&BTRFS_I(inode
)->io_tree
, start
, end
);
3077 static int relocate_file_extent_cluster(struct inode
*inode
,
3078 struct file_extent_cluster
*cluster
)
3082 u64 offset
= BTRFS_I(inode
)->index_cnt
;
3083 unsigned long index
;
3084 unsigned long last_index
;
3086 struct file_ra_state
*ra
;
3087 gfp_t mask
= btrfs_alloc_write_mask(inode
->i_mapping
);
3094 ra
= kzalloc(sizeof(*ra
), GFP_NOFS
);
3098 ret
= prealloc_file_extent_cluster(inode
, cluster
);
3102 file_ra_state_init(ra
, inode
->i_mapping
);
3104 ret
= setup_extent_mapping(inode
, cluster
->start
- offset
,
3105 cluster
->end
- offset
, cluster
->start
);
3109 index
= (cluster
->start
- offset
) >> PAGE_CACHE_SHIFT
;
3110 last_index
= (cluster
->end
- offset
) >> PAGE_CACHE_SHIFT
;
3111 while (index
<= last_index
) {
3112 ret
= btrfs_delalloc_reserve_metadata(inode
, PAGE_CACHE_SIZE
);
3116 page
= find_lock_page(inode
->i_mapping
, index
);
3118 page_cache_sync_readahead(inode
->i_mapping
,
3120 last_index
+ 1 - index
);
3121 page
= find_or_create_page(inode
->i_mapping
, index
,
3124 btrfs_delalloc_release_metadata(inode
,
3131 if (PageReadahead(page
)) {
3132 page_cache_async_readahead(inode
->i_mapping
,
3133 ra
, NULL
, page
, index
,
3134 last_index
+ 1 - index
);
3137 if (!PageUptodate(page
)) {
3138 btrfs_readpage(NULL
, page
);
3140 if (!PageUptodate(page
)) {
3142 page_cache_release(page
);
3143 btrfs_delalloc_release_metadata(inode
,
3150 page_start
= page_offset(page
);
3151 page_end
= page_start
+ PAGE_CACHE_SIZE
- 1;
3153 lock_extent(&BTRFS_I(inode
)->io_tree
, page_start
, page_end
);
3155 set_page_extent_mapped(page
);
3157 if (nr
< cluster
->nr
&&
3158 page_start
+ offset
== cluster
->boundary
[nr
]) {
3159 set_extent_bits(&BTRFS_I(inode
)->io_tree
,
3160 page_start
, page_end
,
3161 EXTENT_BOUNDARY
, GFP_NOFS
);
3165 btrfs_set_extent_delalloc(inode
, page_start
, page_end
, NULL
);
3166 set_page_dirty(page
);
3168 unlock_extent(&BTRFS_I(inode
)->io_tree
,
3169 page_start
, page_end
);
3171 page_cache_release(page
);
3174 balance_dirty_pages_ratelimited(inode
->i_mapping
);
3175 btrfs_throttle(BTRFS_I(inode
)->root
);
3177 WARN_ON(nr
!= cluster
->nr
);
3183 static noinline_for_stack
3184 int relocate_data_extent(struct inode
*inode
, struct btrfs_key
*extent_key
,
3185 struct file_extent_cluster
*cluster
)
3189 if (cluster
->nr
> 0 && extent_key
->objectid
!= cluster
->end
+ 1) {
3190 ret
= relocate_file_extent_cluster(inode
, cluster
);
3197 cluster
->start
= extent_key
->objectid
;
3199 BUG_ON(cluster
->nr
>= MAX_EXTENTS
);
3200 cluster
->end
= extent_key
->objectid
+ extent_key
->offset
- 1;
3201 cluster
->boundary
[cluster
->nr
] = extent_key
->objectid
;
3204 if (cluster
->nr
>= MAX_EXTENTS
) {
3205 ret
= relocate_file_extent_cluster(inode
, cluster
);
3213 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3214 static int get_ref_objectid_v0(struct reloc_control
*rc
,
3215 struct btrfs_path
*path
,
3216 struct btrfs_key
*extent_key
,
3217 u64
*ref_objectid
, int *path_change
)
3219 struct btrfs_key key
;
3220 struct extent_buffer
*leaf
;
3221 struct btrfs_extent_ref_v0
*ref0
;
3225 leaf
= path
->nodes
[0];
3226 slot
= path
->slots
[0];
3228 if (slot
>= btrfs_header_nritems(leaf
)) {
3229 ret
= btrfs_next_leaf(rc
->extent_root
, path
);
3233 leaf
= path
->nodes
[0];
3234 slot
= path
->slots
[0];
3238 btrfs_item_key_to_cpu(leaf
, &key
, slot
);
3239 if (key
.objectid
!= extent_key
->objectid
)
3242 if (key
.type
!= BTRFS_EXTENT_REF_V0_KEY
) {
3246 ref0
= btrfs_item_ptr(leaf
, slot
,
3247 struct btrfs_extent_ref_v0
);
3248 *ref_objectid
= btrfs_ref_objectid_v0(leaf
, ref0
);
3256 * helper to add a tree block to the list.
3257 * the major work is getting the generation and level of the block
3259 static int add_tree_block(struct reloc_control
*rc
,
3260 struct btrfs_key
*extent_key
,
3261 struct btrfs_path
*path
,
3262 struct rb_root
*blocks
)
3264 struct extent_buffer
*eb
;
3265 struct btrfs_extent_item
*ei
;
3266 struct btrfs_tree_block_info
*bi
;
3267 struct tree_block
*block
;
3268 struct rb_node
*rb_node
;
3273 eb
= path
->nodes
[0];
3274 item_size
= btrfs_item_size_nr(eb
, path
->slots
[0]);
3276 if (extent_key
->type
== BTRFS_METADATA_ITEM_KEY
||
3277 item_size
>= sizeof(*ei
) + sizeof(*bi
)) {
3278 ei
= btrfs_item_ptr(eb
, path
->slots
[0],
3279 struct btrfs_extent_item
);
3280 if (extent_key
->type
== BTRFS_EXTENT_ITEM_KEY
) {
3281 bi
= (struct btrfs_tree_block_info
*)(ei
+ 1);
3282 level
= btrfs_tree_block_level(eb
, bi
);
3284 level
= (int)extent_key
->offset
;
3286 generation
= btrfs_extent_generation(eb
, ei
);
3288 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3292 BUG_ON(item_size
!= sizeof(struct btrfs_extent_item_v0
));
3293 ret
= get_ref_objectid_v0(rc
, path
, extent_key
,
3297 BUG_ON(ref_owner
>= BTRFS_MAX_LEVEL
);
3298 level
= (int)ref_owner
;
3299 /* FIXME: get real generation */
3306 btrfs_release_path(path
);
3308 BUG_ON(level
== -1);
3310 block
= kmalloc(sizeof(*block
), GFP_NOFS
);
3314 block
->bytenr
= extent_key
->objectid
;
3315 block
->key
.objectid
= rc
->extent_root
->leafsize
;
3316 block
->key
.offset
= generation
;
3317 block
->level
= level
;
3318 block
->key_ready
= 0;
3320 rb_node
= tree_insert(blocks
, block
->bytenr
, &block
->rb_node
);
3322 backref_tree_panic(rb_node
, -EEXIST
, block
->bytenr
);
3328 * helper to add tree blocks for backref of type BTRFS_SHARED_DATA_REF_KEY
3330 static int __add_tree_block(struct reloc_control
*rc
,
3331 u64 bytenr
, u32 blocksize
,
3332 struct rb_root
*blocks
)
3334 struct btrfs_path
*path
;
3335 struct btrfs_key key
;
3337 bool skinny
= btrfs_fs_incompat(rc
->extent_root
->fs_info
,
3340 if (tree_block_processed(bytenr
, blocksize
, rc
))
3343 if (tree_search(blocks
, bytenr
))
3346 path
= btrfs_alloc_path();
3350 key
.objectid
= bytenr
;
3352 key
.type
= BTRFS_METADATA_ITEM_KEY
;
3353 key
.offset
= (u64
)-1;
3355 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
3356 key
.offset
= blocksize
;
3359 path
->search_commit_root
= 1;
3360 path
->skip_locking
= 1;
3361 ret
= btrfs_search_slot(NULL
, rc
->extent_root
, &key
, path
, 0, 0);
3365 if (ret
> 0 && skinny
) {
3366 if (path
->slots
[0]) {
3368 btrfs_item_key_to_cpu(path
->nodes
[0], &key
,
3370 if (key
.objectid
== bytenr
&&
3371 (key
.type
== BTRFS_METADATA_ITEM_KEY
||
3372 (key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
3373 key
.offset
== blocksize
)))
3379 btrfs_release_path(path
);
3385 ret
= add_tree_block(rc
, &key
, path
, blocks
);
3387 btrfs_free_path(path
);
3392 * helper to check if the block use full backrefs for pointers in it
3394 static int block_use_full_backref(struct reloc_control
*rc
,
3395 struct extent_buffer
*eb
)
3400 if (btrfs_header_flag(eb
, BTRFS_HEADER_FLAG_RELOC
) ||
3401 btrfs_header_backref_rev(eb
) < BTRFS_MIXED_BACKREF_REV
)
3404 ret
= btrfs_lookup_extent_info(NULL
, rc
->extent_root
,
3405 eb
->start
, btrfs_header_level(eb
), 1,
3409 if (flags
& BTRFS_BLOCK_FLAG_FULL_BACKREF
)
3416 static int delete_block_group_cache(struct btrfs_fs_info
*fs_info
,
3417 struct inode
*inode
, u64 ino
)
3419 struct btrfs_key key
;
3420 struct btrfs_root
*root
= fs_info
->tree_root
;
3421 struct btrfs_trans_handle
*trans
;
3428 key
.type
= BTRFS_INODE_ITEM_KEY
;
3431 inode
= btrfs_iget(fs_info
->sb
, &key
, root
, NULL
);
3432 if (IS_ERR(inode
) || is_bad_inode(inode
)) {
3439 ret
= btrfs_check_trunc_cache_free_space(root
,
3440 &fs_info
->global_block_rsv
);
3444 trans
= btrfs_join_transaction(root
);
3445 if (IS_ERR(trans
)) {
3446 ret
= PTR_ERR(trans
);
3450 ret
= btrfs_truncate_free_space_cache(root
, trans
, inode
);
3452 btrfs_end_transaction(trans
, root
);
3453 btrfs_btree_balance_dirty(root
);
3460 * helper to add tree blocks for backref of type BTRFS_EXTENT_DATA_REF_KEY
3461 * this function scans fs tree to find blocks reference the data extent
3463 static int find_data_references(struct reloc_control
*rc
,
3464 struct btrfs_key
*extent_key
,
3465 struct extent_buffer
*leaf
,
3466 struct btrfs_extent_data_ref
*ref
,
3467 struct rb_root
*blocks
)
3469 struct btrfs_path
*path
;
3470 struct tree_block
*block
;
3471 struct btrfs_root
*root
;
3472 struct btrfs_file_extent_item
*fi
;
3473 struct rb_node
*rb_node
;
3474 struct btrfs_key key
;
3485 ref_root
= btrfs_extent_data_ref_root(leaf
, ref
);
3486 ref_objectid
= btrfs_extent_data_ref_objectid(leaf
, ref
);
3487 ref_offset
= btrfs_extent_data_ref_offset(leaf
, ref
);
3488 ref_count
= btrfs_extent_data_ref_count(leaf
, ref
);
3491 * This is an extent belonging to the free space cache, lets just delete
3492 * it and redo the search.
3494 if (ref_root
== BTRFS_ROOT_TREE_OBJECTID
) {
3495 ret
= delete_block_group_cache(rc
->extent_root
->fs_info
,
3496 NULL
, ref_objectid
);
3502 path
= btrfs_alloc_path();
3507 root
= read_fs_root(rc
->extent_root
->fs_info
, ref_root
);
3509 err
= PTR_ERR(root
);
3513 key
.objectid
= ref_objectid
;
3514 key
.type
= BTRFS_EXTENT_DATA_KEY
;
3515 if (ref_offset
> ((u64
)-1 << 32))
3518 key
.offset
= ref_offset
;
3520 path
->search_commit_root
= 1;
3521 path
->skip_locking
= 1;
3522 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
3528 leaf
= path
->nodes
[0];
3529 nritems
= btrfs_header_nritems(leaf
);
3531 * the references in tree blocks that use full backrefs
3532 * are not counted in
3534 if (block_use_full_backref(rc
, leaf
))
3538 rb_node
= tree_search(blocks
, leaf
->start
);
3543 path
->slots
[0] = nritems
;
3546 while (ref_count
> 0) {
3547 while (path
->slots
[0] >= nritems
) {
3548 ret
= btrfs_next_leaf(root
, path
);
3553 if (WARN_ON(ret
> 0))
3556 leaf
= path
->nodes
[0];
3557 nritems
= btrfs_header_nritems(leaf
);
3560 if (block_use_full_backref(rc
, leaf
))
3564 rb_node
= tree_search(blocks
, leaf
->start
);
3569 path
->slots
[0] = nritems
;
3573 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
3574 if (WARN_ON(key
.objectid
!= ref_objectid
||
3575 key
.type
!= BTRFS_EXTENT_DATA_KEY
))
3578 fi
= btrfs_item_ptr(leaf
, path
->slots
[0],
3579 struct btrfs_file_extent_item
);
3581 if (btrfs_file_extent_type(leaf
, fi
) ==
3582 BTRFS_FILE_EXTENT_INLINE
)
3585 if (btrfs_file_extent_disk_bytenr(leaf
, fi
) !=
3586 extent_key
->objectid
)
3589 key
.offset
-= btrfs_file_extent_offset(leaf
, fi
);
3590 if (key
.offset
!= ref_offset
)
3598 if (!tree_block_processed(leaf
->start
, leaf
->len
, rc
)) {
3599 block
= kmalloc(sizeof(*block
), GFP_NOFS
);
3604 block
->bytenr
= leaf
->start
;
3605 btrfs_item_key_to_cpu(leaf
, &block
->key
, 0);
3607 block
->key_ready
= 1;
3608 rb_node
= tree_insert(blocks
, block
->bytenr
,
3611 backref_tree_panic(rb_node
, -EEXIST
,
3617 path
->slots
[0] = nritems
;
3623 btrfs_free_path(path
);
3628 * helper to find all tree blocks that reference a given data extent
3630 static noinline_for_stack
3631 int add_data_references(struct reloc_control
*rc
,
3632 struct btrfs_key
*extent_key
,
3633 struct btrfs_path
*path
,
3634 struct rb_root
*blocks
)
3636 struct btrfs_key key
;
3637 struct extent_buffer
*eb
;
3638 struct btrfs_extent_data_ref
*dref
;
3639 struct btrfs_extent_inline_ref
*iref
;
3642 u32 blocksize
= btrfs_level_size(rc
->extent_root
, 0);
3646 eb
= path
->nodes
[0];
3647 ptr
= btrfs_item_ptr_offset(eb
, path
->slots
[0]);
3648 end
= ptr
+ btrfs_item_size_nr(eb
, path
->slots
[0]);
3649 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3650 if (ptr
+ sizeof(struct btrfs_extent_item_v0
) == end
)
3654 ptr
+= sizeof(struct btrfs_extent_item
);
3657 iref
= (struct btrfs_extent_inline_ref
*)ptr
;
3658 key
.type
= btrfs_extent_inline_ref_type(eb
, iref
);
3659 if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
) {
3660 key
.offset
= btrfs_extent_inline_ref_offset(eb
, iref
);
3661 ret
= __add_tree_block(rc
, key
.offset
, blocksize
,
3663 } else if (key
.type
== BTRFS_EXTENT_DATA_REF_KEY
) {
3664 dref
= (struct btrfs_extent_data_ref
*)(&iref
->offset
);
3665 ret
= find_data_references(rc
, extent_key
,
3674 ptr
+= btrfs_extent_inline_ref_size(key
.type
);
3680 eb
= path
->nodes
[0];
3681 if (path
->slots
[0] >= btrfs_header_nritems(eb
)) {
3682 ret
= btrfs_next_leaf(rc
->extent_root
, path
);
3689 eb
= path
->nodes
[0];
3692 btrfs_item_key_to_cpu(eb
, &key
, path
->slots
[0]);
3693 if (key
.objectid
!= extent_key
->objectid
)
3696 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3697 if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
||
3698 key
.type
== BTRFS_EXTENT_REF_V0_KEY
) {
3700 BUG_ON(key
.type
== BTRFS_EXTENT_REF_V0_KEY
);
3701 if (key
.type
== BTRFS_SHARED_DATA_REF_KEY
) {
3703 ret
= __add_tree_block(rc
, key
.offset
, blocksize
,
3705 } else if (key
.type
== BTRFS_EXTENT_DATA_REF_KEY
) {
3706 dref
= btrfs_item_ptr(eb
, path
->slots
[0],
3707 struct btrfs_extent_data_ref
);
3708 ret
= find_data_references(rc
, extent_key
,
3720 btrfs_release_path(path
);
3722 free_block_list(blocks
);
3727 * helper to find next unprocessed extent
3729 static noinline_for_stack
3730 int find_next_extent(struct btrfs_trans_handle
*trans
,
3731 struct reloc_control
*rc
, struct btrfs_path
*path
,
3732 struct btrfs_key
*extent_key
)
3734 struct btrfs_key key
;
3735 struct extent_buffer
*leaf
;
3736 u64 start
, end
, last
;
3739 last
= rc
->block_group
->key
.objectid
+ rc
->block_group
->key
.offset
;
3742 if (rc
->search_start
>= last
) {
3747 key
.objectid
= rc
->search_start
;
3748 key
.type
= BTRFS_EXTENT_ITEM_KEY
;
3751 path
->search_commit_root
= 1;
3752 path
->skip_locking
= 1;
3753 ret
= btrfs_search_slot(NULL
, rc
->extent_root
, &key
, path
,
3758 leaf
= path
->nodes
[0];
3759 if (path
->slots
[0] >= btrfs_header_nritems(leaf
)) {
3760 ret
= btrfs_next_leaf(rc
->extent_root
, path
);
3763 leaf
= path
->nodes
[0];
3766 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
3767 if (key
.objectid
>= last
) {
3772 if (key
.type
!= BTRFS_EXTENT_ITEM_KEY
&&
3773 key
.type
!= BTRFS_METADATA_ITEM_KEY
) {
3778 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
&&
3779 key
.objectid
+ key
.offset
<= rc
->search_start
) {
3784 if (key
.type
== BTRFS_METADATA_ITEM_KEY
&&
3785 key
.objectid
+ rc
->extent_root
->leafsize
<=
3791 ret
= find_first_extent_bit(&rc
->processed_blocks
,
3792 key
.objectid
, &start
, &end
,
3793 EXTENT_DIRTY
, NULL
);
3795 if (ret
== 0 && start
<= key
.objectid
) {
3796 btrfs_release_path(path
);
3797 rc
->search_start
= end
+ 1;
3799 if (key
.type
== BTRFS_EXTENT_ITEM_KEY
)
3800 rc
->search_start
= key
.objectid
+ key
.offset
;
3802 rc
->search_start
= key
.objectid
+
3803 rc
->extent_root
->leafsize
;
3804 memcpy(extent_key
, &key
, sizeof(key
));
3808 btrfs_release_path(path
);
3812 static void set_reloc_control(struct reloc_control
*rc
)
3814 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3816 mutex_lock(&fs_info
->reloc_mutex
);
3817 fs_info
->reloc_ctl
= rc
;
3818 mutex_unlock(&fs_info
->reloc_mutex
);
3821 static void unset_reloc_control(struct reloc_control
*rc
)
3823 struct btrfs_fs_info
*fs_info
= rc
->extent_root
->fs_info
;
3825 mutex_lock(&fs_info
->reloc_mutex
);
3826 fs_info
->reloc_ctl
= NULL
;
3827 mutex_unlock(&fs_info
->reloc_mutex
);
3830 static int check_extent_flags(u64 flags
)
3832 if ((flags
& BTRFS_EXTENT_FLAG_DATA
) &&
3833 (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
))
3835 if (!(flags
& BTRFS_EXTENT_FLAG_DATA
) &&
3836 !(flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
))
3838 if ((flags
& BTRFS_EXTENT_FLAG_DATA
) &&
3839 (flags
& BTRFS_BLOCK_FLAG_FULL_BACKREF
))
3844 static noinline_for_stack
3845 int prepare_to_relocate(struct reloc_control
*rc
)
3847 struct btrfs_trans_handle
*trans
;
3849 rc
->block_rsv
= btrfs_alloc_block_rsv(rc
->extent_root
,
3850 BTRFS_BLOCK_RSV_TEMP
);
3854 memset(&rc
->cluster
, 0, sizeof(rc
->cluster
));
3855 rc
->search_start
= rc
->block_group
->key
.objectid
;
3856 rc
->extents_found
= 0;
3857 rc
->nodes_relocated
= 0;
3858 rc
->merging_rsv_size
= 0;
3859 rc
->reserved_bytes
= 0;
3860 rc
->block_rsv
->size
= rc
->extent_root
->nodesize
*
3861 RELOCATION_RESERVED_NODES
;
3863 rc
->create_reloc_tree
= 1;
3864 set_reloc_control(rc
);
3866 trans
= btrfs_join_transaction(rc
->extent_root
);
3867 if (IS_ERR(trans
)) {
3868 unset_reloc_control(rc
);
3870 * extent tree is not a ref_cow tree and has no reloc_root to
3871 * cleanup. And callers are responsible to free the above
3874 return PTR_ERR(trans
);
3876 btrfs_commit_transaction(trans
, rc
->extent_root
);
3880 static noinline_for_stack
int relocate_block_group(struct reloc_control
*rc
)
3882 struct rb_root blocks
= RB_ROOT
;
3883 struct btrfs_key key
;
3884 struct btrfs_trans_handle
*trans
= NULL
;
3885 struct btrfs_path
*path
;
3886 struct btrfs_extent_item
*ei
;
3893 path
= btrfs_alloc_path();
3898 ret
= prepare_to_relocate(rc
);
3905 rc
->reserved_bytes
= 0;
3906 ret
= btrfs_block_rsv_refill(rc
->extent_root
,
3907 rc
->block_rsv
, rc
->block_rsv
->size
,
3908 BTRFS_RESERVE_FLUSH_ALL
);
3914 trans
= btrfs_start_transaction(rc
->extent_root
, 0);
3915 if (IS_ERR(trans
)) {
3916 err
= PTR_ERR(trans
);
3921 if (update_backref_cache(trans
, &rc
->backref_cache
)) {
3922 btrfs_end_transaction(trans
, rc
->extent_root
);
3926 ret
= find_next_extent(trans
, rc
, path
, &key
);
3932 rc
->extents_found
++;
3934 ei
= btrfs_item_ptr(path
->nodes
[0], path
->slots
[0],
3935 struct btrfs_extent_item
);
3936 item_size
= btrfs_item_size_nr(path
->nodes
[0], path
->slots
[0]);
3937 if (item_size
>= sizeof(*ei
)) {
3938 flags
= btrfs_extent_flags(path
->nodes
[0], ei
);
3939 ret
= check_extent_flags(flags
);
3943 #ifdef BTRFS_COMPAT_EXTENT_TREE_V0
3945 int path_change
= 0;
3948 sizeof(struct btrfs_extent_item_v0
));
3949 ret
= get_ref_objectid_v0(rc
, path
, &key
, &ref_owner
,
3951 if (ref_owner
< BTRFS_FIRST_FREE_OBJECTID
)
3952 flags
= BTRFS_EXTENT_FLAG_TREE_BLOCK
;
3954 flags
= BTRFS_EXTENT_FLAG_DATA
;
3957 btrfs_release_path(path
);
3959 path
->search_commit_root
= 1;
3960 path
->skip_locking
= 1;
3961 ret
= btrfs_search_slot(NULL
, rc
->extent_root
,
3974 if (flags
& BTRFS_EXTENT_FLAG_TREE_BLOCK
) {
3975 ret
= add_tree_block(rc
, &key
, path
, &blocks
);
3976 } else if (rc
->stage
== UPDATE_DATA_PTRS
&&
3977 (flags
& BTRFS_EXTENT_FLAG_DATA
)) {
3978 ret
= add_data_references(rc
, &key
, path
, &blocks
);
3980 btrfs_release_path(path
);
3988 if (!RB_EMPTY_ROOT(&blocks
)) {
3989 ret
= relocate_tree_blocks(trans
, rc
, &blocks
);
3992 * if we fail to relocate tree blocks, force to update
3993 * backref cache when committing transaction.
3995 rc
->backref_cache
.last_trans
= trans
->transid
- 1;
3997 if (ret
!= -EAGAIN
) {
4001 rc
->extents_found
--;
4002 rc
->search_start
= key
.objectid
;
4006 btrfs_end_transaction_throttle(trans
, rc
->extent_root
);
4007 btrfs_btree_balance_dirty(rc
->extent_root
);
4010 if (rc
->stage
== MOVE_DATA_EXTENTS
&&
4011 (flags
& BTRFS_EXTENT_FLAG_DATA
)) {
4012 rc
->found_file_extent
= 1;
4013 ret
= relocate_data_extent(rc
->data_inode
,
4014 &key
, &rc
->cluster
);
4021 if (trans
&& progress
&& err
== -ENOSPC
) {
4022 ret
= btrfs_force_chunk_alloc(trans
, rc
->extent_root
,
4023 rc
->block_group
->flags
);
4031 btrfs_release_path(path
);
4032 clear_extent_bits(&rc
->processed_blocks
, 0, (u64
)-1, EXTENT_DIRTY
,
4036 btrfs_end_transaction_throttle(trans
, rc
->extent_root
);
4037 btrfs_btree_balance_dirty(rc
->extent_root
);
4041 ret
= relocate_file_extent_cluster(rc
->data_inode
,
4047 rc
->create_reloc_tree
= 0;
4048 set_reloc_control(rc
);
4050 backref_cache_cleanup(&rc
->backref_cache
);
4051 btrfs_block_rsv_release(rc
->extent_root
, rc
->block_rsv
, (u64
)-1);
4053 err
= prepare_to_merge(rc
, err
);
4055 merge_reloc_roots(rc
);
4057 rc
->merge_reloc_tree
= 0;
4058 unset_reloc_control(rc
);
4059 btrfs_block_rsv_release(rc
->extent_root
, rc
->block_rsv
, (u64
)-1);
4061 /* get rid of pinned extents */
4062 trans
= btrfs_join_transaction(rc
->extent_root
);
4064 err
= PTR_ERR(trans
);
4066 btrfs_commit_transaction(trans
, rc
->extent_root
);
4068 btrfs_free_block_rsv(rc
->extent_root
, rc
->block_rsv
);
4069 btrfs_free_path(path
);
4073 static int __insert_orphan_inode(struct btrfs_trans_handle
*trans
,
4074 struct btrfs_root
*root
, u64 objectid
)
4076 struct btrfs_path
*path
;
4077 struct btrfs_inode_item
*item
;
4078 struct extent_buffer
*leaf
;
4081 path
= btrfs_alloc_path();
4085 ret
= btrfs_insert_empty_inode(trans
, root
, path
, objectid
);
4089 leaf
= path
->nodes
[0];
4090 item
= btrfs_item_ptr(leaf
, path
->slots
[0], struct btrfs_inode_item
);
4091 memset_extent_buffer(leaf
, 0, (unsigned long)item
, sizeof(*item
));
4092 btrfs_set_inode_generation(leaf
, item
, 1);
4093 btrfs_set_inode_size(leaf
, item
, 0);
4094 btrfs_set_inode_mode(leaf
, item
, S_IFREG
| 0600);
4095 btrfs_set_inode_flags(leaf
, item
, BTRFS_INODE_NOCOMPRESS
|
4096 BTRFS_INODE_PREALLOC
);
4097 btrfs_mark_buffer_dirty(leaf
);
4098 btrfs_release_path(path
);
4100 btrfs_free_path(path
);
4105 * helper to create inode for data relocation.
4106 * the inode is in data relocation tree and its link count is 0
4108 static noinline_for_stack
4109 struct inode
*create_reloc_inode(struct btrfs_fs_info
*fs_info
,
4110 struct btrfs_block_group_cache
*group
)
4112 struct inode
*inode
= NULL
;
4113 struct btrfs_trans_handle
*trans
;
4114 struct btrfs_root
*root
;
4115 struct btrfs_key key
;
4116 u64 objectid
= BTRFS_FIRST_FREE_OBJECTID
;
4119 root
= read_fs_root(fs_info
, BTRFS_DATA_RELOC_TREE_OBJECTID
);
4121 return ERR_CAST(root
);
4123 trans
= btrfs_start_transaction(root
, 6);
4125 return ERR_CAST(trans
);
4127 err
= btrfs_find_free_objectid(root
, &objectid
);
4131 err
= __insert_orphan_inode(trans
, root
, objectid
);
4134 key
.objectid
= objectid
;
4135 key
.type
= BTRFS_INODE_ITEM_KEY
;
4137 inode
= btrfs_iget(root
->fs_info
->sb
, &key
, root
, NULL
);
4138 BUG_ON(IS_ERR(inode
) || is_bad_inode(inode
));
4139 BTRFS_I(inode
)->index_cnt
= group
->key
.objectid
;
4141 err
= btrfs_orphan_add(trans
, inode
);
4143 btrfs_end_transaction(trans
, root
);
4144 btrfs_btree_balance_dirty(root
);
4148 inode
= ERR_PTR(err
);
4153 static struct reloc_control
*alloc_reloc_control(struct btrfs_fs_info
*fs_info
)
4155 struct reloc_control
*rc
;
4157 rc
= kzalloc(sizeof(*rc
), GFP_NOFS
);
4161 INIT_LIST_HEAD(&rc
->reloc_roots
);
4162 backref_cache_init(&rc
->backref_cache
);
4163 mapping_tree_init(&rc
->reloc_root_tree
);
4164 extent_io_tree_init(&rc
->processed_blocks
,
4165 fs_info
->btree_inode
->i_mapping
);
4170 * function to relocate all extents in a block group.
4172 int btrfs_relocate_block_group(struct btrfs_root
*extent_root
, u64 group_start
)
4174 struct btrfs_fs_info
*fs_info
= extent_root
->fs_info
;
4175 struct reloc_control
*rc
;
4176 struct inode
*inode
;
4177 struct btrfs_path
*path
;
4182 rc
= alloc_reloc_control(fs_info
);
4186 rc
->extent_root
= extent_root
;
4188 rc
->block_group
= btrfs_lookup_block_group(fs_info
, group_start
);
4189 BUG_ON(!rc
->block_group
);
4191 if (!rc
->block_group
->ro
) {
4192 ret
= btrfs_set_block_group_ro(extent_root
, rc
->block_group
);
4200 path
= btrfs_alloc_path();
4206 inode
= lookup_free_space_inode(fs_info
->tree_root
, rc
->block_group
,
4208 btrfs_free_path(path
);
4211 ret
= delete_block_group_cache(fs_info
, inode
, 0);
4213 ret
= PTR_ERR(inode
);
4215 if (ret
&& ret
!= -ENOENT
) {
4220 rc
->data_inode
= create_reloc_inode(fs_info
, rc
->block_group
);
4221 if (IS_ERR(rc
->data_inode
)) {
4222 err
= PTR_ERR(rc
->data_inode
);
4223 rc
->data_inode
= NULL
;
4227 btrfs_info(extent_root
->fs_info
, "relocating block group %llu flags %llu",
4228 rc
->block_group
->key
.objectid
, rc
->block_group
->flags
);
4230 ret
= btrfs_start_delalloc_roots(fs_info
, 0, -1);
4235 btrfs_wait_ordered_roots(fs_info
, -1);
4238 mutex_lock(&fs_info
->cleaner_mutex
);
4239 ret
= relocate_block_group(rc
);
4240 mutex_unlock(&fs_info
->cleaner_mutex
);
4246 if (rc
->extents_found
== 0)
4249 btrfs_info(extent_root
->fs_info
, "found %llu extents",
4252 if (rc
->stage
== MOVE_DATA_EXTENTS
&& rc
->found_file_extent
) {
4253 ret
= btrfs_wait_ordered_range(rc
->data_inode
, 0,
4259 invalidate_mapping_pages(rc
->data_inode
->i_mapping
,
4261 rc
->stage
= UPDATE_DATA_PTRS
;
4265 WARN_ON(rc
->block_group
->pinned
> 0);
4266 WARN_ON(rc
->block_group
->reserved
> 0);
4267 WARN_ON(btrfs_block_group_used(&rc
->block_group
->item
) > 0);
4270 btrfs_set_block_group_rw(extent_root
, rc
->block_group
);
4271 iput(rc
->data_inode
);
4272 btrfs_put_block_group(rc
->block_group
);
4277 static noinline_for_stack
int mark_garbage_root(struct btrfs_root
*root
)
4279 struct btrfs_trans_handle
*trans
;
4282 trans
= btrfs_start_transaction(root
->fs_info
->tree_root
, 0);
4284 return PTR_ERR(trans
);
4286 memset(&root
->root_item
.drop_progress
, 0,
4287 sizeof(root
->root_item
.drop_progress
));
4288 root
->root_item
.drop_level
= 0;
4289 btrfs_set_root_refs(&root
->root_item
, 0);
4290 ret
= btrfs_update_root(trans
, root
->fs_info
->tree_root
,
4291 &root
->root_key
, &root
->root_item
);
4293 err
= btrfs_end_transaction(trans
, root
->fs_info
->tree_root
);
4300 * recover relocation interrupted by system crash.
4302 * this function resumes merging reloc trees with corresponding fs trees.
4303 * this is important for keeping the sharing of tree blocks
4305 int btrfs_recover_relocation(struct btrfs_root
*root
)
4307 LIST_HEAD(reloc_roots
);
4308 struct btrfs_key key
;
4309 struct btrfs_root
*fs_root
;
4310 struct btrfs_root
*reloc_root
;
4311 struct btrfs_path
*path
;
4312 struct extent_buffer
*leaf
;
4313 struct reloc_control
*rc
= NULL
;
4314 struct btrfs_trans_handle
*trans
;
4318 path
= btrfs_alloc_path();
4323 key
.objectid
= BTRFS_TREE_RELOC_OBJECTID
;
4324 key
.type
= BTRFS_ROOT_ITEM_KEY
;
4325 key
.offset
= (u64
)-1;
4328 ret
= btrfs_search_slot(NULL
, root
->fs_info
->tree_root
, &key
,
4335 if (path
->slots
[0] == 0)
4339 leaf
= path
->nodes
[0];
4340 btrfs_item_key_to_cpu(leaf
, &key
, path
->slots
[0]);
4341 btrfs_release_path(path
);
4343 if (key
.objectid
!= BTRFS_TREE_RELOC_OBJECTID
||
4344 key
.type
!= BTRFS_ROOT_ITEM_KEY
)
4347 reloc_root
= btrfs_read_fs_root(root
, &key
);
4348 if (IS_ERR(reloc_root
)) {
4349 err
= PTR_ERR(reloc_root
);
4353 list_add(&reloc_root
->root_list
, &reloc_roots
);
4355 if (btrfs_root_refs(&reloc_root
->root_item
) > 0) {
4356 fs_root
= read_fs_root(root
->fs_info
,
4357 reloc_root
->root_key
.offset
);
4358 if (IS_ERR(fs_root
)) {
4359 ret
= PTR_ERR(fs_root
);
4360 if (ret
!= -ENOENT
) {
4364 ret
= mark_garbage_root(reloc_root
);
4372 if (key
.offset
== 0)
4377 btrfs_release_path(path
);
4379 if (list_empty(&reloc_roots
))
4382 rc
= alloc_reloc_control(root
->fs_info
);
4388 rc
->extent_root
= root
->fs_info
->extent_root
;
4390 set_reloc_control(rc
);
4392 trans
= btrfs_join_transaction(rc
->extent_root
);
4393 if (IS_ERR(trans
)) {
4394 unset_reloc_control(rc
);
4395 err
= PTR_ERR(trans
);
4399 rc
->merge_reloc_tree
= 1;
4401 while (!list_empty(&reloc_roots
)) {
4402 reloc_root
= list_entry(reloc_roots
.next
,
4403 struct btrfs_root
, root_list
);
4404 list_del(&reloc_root
->root_list
);
4406 if (btrfs_root_refs(&reloc_root
->root_item
) == 0) {
4407 list_add_tail(&reloc_root
->root_list
,
4412 fs_root
= read_fs_root(root
->fs_info
,
4413 reloc_root
->root_key
.offset
);
4414 if (IS_ERR(fs_root
)) {
4415 err
= PTR_ERR(fs_root
);
4419 err
= __add_reloc_root(reloc_root
);
4420 BUG_ON(err
< 0); /* -ENOMEM or logic error */
4421 fs_root
->reloc_root
= reloc_root
;
4424 err
= btrfs_commit_transaction(trans
, rc
->extent_root
);
4428 merge_reloc_roots(rc
);
4430 unset_reloc_control(rc
);
4432 trans
= btrfs_join_transaction(rc
->extent_root
);
4434 err
= PTR_ERR(trans
);
4436 err
= btrfs_commit_transaction(trans
, rc
->extent_root
);
4440 if (!list_empty(&reloc_roots
))
4441 free_reloc_roots(&reloc_roots
);
4443 btrfs_free_path(path
);
4446 /* cleanup orphan inode in data relocation tree */
4447 fs_root
= read_fs_root(root
->fs_info
,
4448 BTRFS_DATA_RELOC_TREE_OBJECTID
);
4449 if (IS_ERR(fs_root
))
4450 err
= PTR_ERR(fs_root
);
4452 err
= btrfs_orphan_cleanup(fs_root
);
4458 * helper to add ordered checksum for data relocation.
4460 * cloning checksum properly handles the nodatasum extents.
4461 * it also saves CPU time to re-calculate the checksum.
4463 int btrfs_reloc_clone_csums(struct inode
*inode
, u64 file_pos
, u64 len
)
4465 struct btrfs_ordered_sum
*sums
;
4466 struct btrfs_ordered_extent
*ordered
;
4467 struct btrfs_root
*root
= BTRFS_I(inode
)->root
;
4473 ordered
= btrfs_lookup_ordered_extent(inode
, file_pos
);
4474 BUG_ON(ordered
->file_offset
!= file_pos
|| ordered
->len
!= len
);
4476 disk_bytenr
= file_pos
+ BTRFS_I(inode
)->index_cnt
;
4477 ret
= btrfs_lookup_csums_range(root
->fs_info
->csum_root
, disk_bytenr
,
4478 disk_bytenr
+ len
- 1, &list
, 0);
4482 while (!list_empty(&list
)) {
4483 sums
= list_entry(list
.next
, struct btrfs_ordered_sum
, list
);
4484 list_del_init(&sums
->list
);
4487 * We need to offset the new_bytenr based on where the csum is.
4488 * We need to do this because we will read in entire prealloc
4489 * extents but we may have written to say the middle of the
4490 * prealloc extent, so we need to make sure the csum goes with
4491 * the right disk offset.
4493 * We can do this because the data reloc inode refers strictly
4494 * to the on disk bytes, so we don't have to worry about
4495 * disk_len vs real len like with real inodes since it's all
4498 new_bytenr
= ordered
->start
+ (sums
->bytenr
- disk_bytenr
);
4499 sums
->bytenr
= new_bytenr
;
4501 btrfs_add_ordered_sum(inode
, ordered
, sums
);
4504 btrfs_put_ordered_extent(ordered
);
4508 int btrfs_reloc_cow_block(struct btrfs_trans_handle
*trans
,
4509 struct btrfs_root
*root
, struct extent_buffer
*buf
,
4510 struct extent_buffer
*cow
)
4512 struct reloc_control
*rc
;
4513 struct backref_node
*node
;
4518 rc
= root
->fs_info
->reloc_ctl
;
4522 BUG_ON(rc
->stage
== UPDATE_DATA_PTRS
&&
4523 root
->root_key
.objectid
== BTRFS_DATA_RELOC_TREE_OBJECTID
);
4525 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
) {
4526 if (buf
== root
->node
)
4527 __update_reloc_root(root
, cow
->start
);
4530 level
= btrfs_header_level(buf
);
4531 if (btrfs_header_generation(buf
) <=
4532 btrfs_root_last_snapshot(&root
->root_item
))
4535 if (root
->root_key
.objectid
== BTRFS_TREE_RELOC_OBJECTID
&&
4536 rc
->create_reloc_tree
) {
4537 WARN_ON(!first_cow
&& level
== 0);
4539 node
= rc
->backref_cache
.path
[level
];
4540 BUG_ON(node
->bytenr
!= buf
->start
&&
4541 node
->new_bytenr
!= buf
->start
);
4543 drop_node_buffer(node
);
4544 extent_buffer_get(cow
);
4546 node
->new_bytenr
= cow
->start
;
4548 if (!node
->pending
) {
4549 list_move_tail(&node
->list
,
4550 &rc
->backref_cache
.pending
[level
]);
4555 __mark_block_processed(rc
, node
);
4557 if (first_cow
&& level
> 0)
4558 rc
->nodes_relocated
+= buf
->len
;
4561 if (level
== 0 && first_cow
&& rc
->stage
== UPDATE_DATA_PTRS
)
4562 ret
= replace_file_extents(trans
, rc
, root
, cow
);
4567 * called before creating snapshot. it calculates metadata reservation
4568 * requried for relocating tree blocks in the snapshot
4570 void btrfs_reloc_pre_snapshot(struct btrfs_trans_handle
*trans
,
4571 struct btrfs_pending_snapshot
*pending
,
4572 u64
*bytes_to_reserve
)
4574 struct btrfs_root
*root
;
4575 struct reloc_control
*rc
;
4577 root
= pending
->root
;
4578 if (!root
->reloc_root
)
4581 rc
= root
->fs_info
->reloc_ctl
;
4582 if (!rc
->merge_reloc_tree
)
4585 root
= root
->reloc_root
;
4586 BUG_ON(btrfs_root_refs(&root
->root_item
) == 0);
4588 * relocation is in the stage of merging trees. the space
4589 * used by merging a reloc tree is twice the size of
4590 * relocated tree nodes in the worst case. half for cowing
4591 * the reloc tree, half for cowing the fs tree. the space
4592 * used by cowing the reloc tree will be freed after the
4593 * tree is dropped. if we create snapshot, cowing the fs
4594 * tree may use more space than it frees. so we need
4595 * reserve extra space.
4597 *bytes_to_reserve
+= rc
->nodes_relocated
;
4601 * called after snapshot is created. migrate block reservation
4602 * and create reloc root for the newly created snapshot
4604 int btrfs_reloc_post_snapshot(struct btrfs_trans_handle
*trans
,
4605 struct btrfs_pending_snapshot
*pending
)
4607 struct btrfs_root
*root
= pending
->root
;
4608 struct btrfs_root
*reloc_root
;
4609 struct btrfs_root
*new_root
;
4610 struct reloc_control
*rc
;
4613 if (!root
->reloc_root
)
4616 rc
= root
->fs_info
->reloc_ctl
;
4617 rc
->merging_rsv_size
+= rc
->nodes_relocated
;
4619 if (rc
->merge_reloc_tree
) {
4620 ret
= btrfs_block_rsv_migrate(&pending
->block_rsv
,
4622 rc
->nodes_relocated
);
4627 new_root
= pending
->snap
;
4628 reloc_root
= create_reloc_root(trans
, root
->reloc_root
,
4629 new_root
->root_key
.objectid
);
4630 if (IS_ERR(reloc_root
))
4631 return PTR_ERR(reloc_root
);
4633 ret
= __add_reloc_root(reloc_root
);
4635 new_root
->reloc_root
= reloc_root
;
4637 if (rc
->create_reloc_tree
)
4638 ret
= clone_backref_node(trans
, rc
, root
, reloc_root
);