1 #include <linux/module.h>
3 #include <linux/blkdev.h>
4 #include <linux/crypto.h>
5 #include <linux/scatterlist.h>
6 #include <linux/swap.h>
7 #include <linux/radix-tree.h>
10 #include "transaction.h"
11 #include "btrfs_inode.h"
17 struct block_device
*bdev
;
20 int btrfs_insert_dev_radix(struct btrfs_root
*root
,
21 struct block_device
*bdev
,
26 struct dev_lookup
*lookup
;
29 lookup
= kmalloc(sizeof(*lookup
), GFP_NOFS
);
32 lookup
->block_start
= block_start
;
33 lookup
->num_blocks
= num_blocks
;
35 lookup
->device_id
= device_id
;
37 ret
= radix_tree_insert(&root
->fs_info
->dev_radix
, block_start
+
38 num_blocks
- 1, lookup
);
42 u64
bh_blocknr(struct buffer_head
*bh
)
44 int blkbits
= bh
->b_page
->mapping
->host
->i_blkbits
;
45 u64 blocknr
= bh
->b_page
->index
<< (PAGE_CACHE_SHIFT
- blkbits
);
48 if (PageHighMem(bh
->b_page
))
49 offset
= (unsigned long)bh
->b_data
;
51 offset
= bh
->b_data
- (char *)page_address(bh
->b_page
);
52 blocknr
+= offset
>> (PAGE_CACHE_SHIFT
- blkbits
);
56 static int check_tree_block(struct btrfs_root
*root
, struct buffer_head
*buf
)
58 struct btrfs_node
*node
= btrfs_buffer_node(buf
);
59 if (bh_blocknr(buf
) != btrfs_header_blocknr(&node
->header
)) {
60 printk(KERN_CRIT
"bh_blocknr(buf) is %Lu, header is %Lu\n",
61 bh_blocknr(buf
), btrfs_header_blocknr(&node
->header
));
67 struct buffer_head
*btrfs_find_tree_block(struct btrfs_root
*root
, u64 blocknr
)
69 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
70 int blockbits
= root
->fs_info
->sb
->s_blocksize_bits
;
71 unsigned long index
= blocknr
>> (PAGE_CACHE_SHIFT
- blockbits
);
73 struct buffer_head
*bh
;
74 struct buffer_head
*head
;
75 struct buffer_head
*ret
= NULL
;
78 page
= find_lock_page(mapping
, index
);
82 if (!page_has_buffers(page
))
85 head
= page_buffers(page
);
88 if (buffer_mapped(bh
) && bh_blocknr(bh
) == blocknr
) {
100 page_cache_release(page
);
104 int btrfs_map_bh_to_logical(struct btrfs_root
*root
, struct buffer_head
*bh
,
107 struct dev_lookup
*lookup
[2];
111 root
= root
->fs_info
->dev_root
;
112 ret
= radix_tree_gang_lookup(&root
->fs_info
->dev_radix
,
114 (unsigned long)logical
,
116 if (ret
== 0 || lookup
[0]->block_start
> logical
||
117 lookup
[0]->block_start
+ lookup
[0]->num_blocks
<= logical
) {
121 bh
->b_bdev
= lookup
[0]->bdev
;
122 bh
->b_blocknr
= logical
- lookup
[0]->block_start
;
123 set_buffer_mapped(bh
);
129 struct buffer_head
*btrfs_find_create_tree_block(struct btrfs_root
*root
,
132 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
133 int blockbits
= root
->fs_info
->sb
->s_blocksize_bits
;
134 unsigned long index
= blocknr
>> (PAGE_CACHE_SHIFT
- blockbits
);
136 struct buffer_head
*bh
;
137 struct buffer_head
*head
;
138 struct buffer_head
*ret
= NULL
;
140 u64 first_block
= index
<< (PAGE_CACHE_SHIFT
- blockbits
);
142 page
= grab_cache_page(mapping
, index
);
146 if (!page_has_buffers(page
))
147 create_empty_buffers(page
, root
->fs_info
->sb
->s_blocksize
, 0);
148 head
= page_buffers(page
);
151 if (!buffer_mapped(bh
)) {
152 err
= btrfs_map_bh_to_logical(root
, bh
, first_block
);
155 if (bh_blocknr(bh
) == blocknr
) {
160 bh
= bh
->b_this_page
;
162 } while (bh
!= head
);
167 page_cache_release(page
);
171 static int btree_get_block(struct inode
*inode
, sector_t iblock
,
172 struct buffer_head
*bh
, int create
)
175 struct btrfs_root
*root
= BTRFS_I(bh
->b_page
->mapping
->host
)->root
;
176 err
= btrfs_map_bh_to_logical(root
, bh
, iblock
);
180 int btrfs_csum_data(struct btrfs_root
* root
, char *data
, size_t len
,
183 struct scatterlist sg
;
184 struct crypto_hash
*tfm
= root
->fs_info
->hash_tfm
;
185 struct hash_desc desc
;
190 sg_init_one(&sg
, data
, len
);
191 spin_lock(&root
->fs_info
->hash_lock
);
192 ret
= crypto_hash_digest(&desc
, &sg
, 1, result
);
193 spin_unlock(&root
->fs_info
->hash_lock
);
195 printk("sha256 digest failed\n");
199 static int csum_tree_block(struct btrfs_root
*root
, struct buffer_head
*bh
,
202 char result
[BTRFS_CSUM_SIZE
];
204 struct btrfs_node
*node
;
206 ret
= btrfs_csum_data(root
, bh
->b_data
+ BTRFS_CSUM_SIZE
,
207 bh
->b_size
- BTRFS_CSUM_SIZE
, result
);
211 if (memcmp(bh
->b_data
, result
, BTRFS_CSUM_SIZE
)) {
212 printk("checksum verify failed on %Lu\n",
217 node
= btrfs_buffer_node(bh
);
218 memcpy(node
->header
.csum
, result
, BTRFS_CSUM_SIZE
);
223 static int btree_writepage(struct page
*page
, struct writeback_control
*wbc
)
225 struct buffer_head
*bh
;
226 struct btrfs_root
*root
= BTRFS_I(page
->mapping
->host
)->root
;
227 struct buffer_head
*head
;
228 if (!page_has_buffers(page
)) {
229 create_empty_buffers(page
, root
->fs_info
->sb
->s_blocksize
,
230 (1 << BH_Dirty
)|(1 << BH_Uptodate
));
232 head
= page_buffers(page
);
235 if (buffer_dirty(bh
))
236 csum_tree_block(root
, bh
, 0);
237 bh
= bh
->b_this_page
;
238 } while (bh
!= head
);
239 return block_write_full_page(page
, btree_get_block
, wbc
);
242 static int btree_readpage(struct file
* file
, struct page
* page
)
244 return block_read_full_page(page
, btree_get_block
);
247 static struct address_space_operations btree_aops
= {
248 .readpage
= btree_readpage
,
249 .writepage
= btree_writepage
,
250 .sync_page
= block_sync_page
,
253 struct buffer_head
*read_tree_block(struct btrfs_root
*root
, u64 blocknr
)
255 struct buffer_head
*bh
= NULL
;
257 bh
= btrfs_find_create_tree_block(root
, blocknr
);
260 if (buffer_uptodate(bh
))
263 if (!buffer_uptodate(bh
)) {
265 bh
->b_end_io
= end_buffer_read_sync
;
268 if (!buffer_uptodate(bh
))
270 csum_tree_block(root
, bh
, 1);
275 if (check_tree_block(root
, bh
))
283 int dirty_tree_block(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
284 struct buffer_head
*buf
)
286 WARN_ON(atomic_read(&buf
->b_count
) == 0);
287 mark_buffer_dirty(buf
);
291 int clean_tree_block(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
292 struct buffer_head
*buf
)
294 WARN_ON(atomic_read(&buf
->b_count
) == 0);
295 clear_buffer_dirty(buf
);
299 static int __setup_root(int blocksize
,
300 struct btrfs_root
*root
,
301 struct btrfs_fs_info
*fs_info
,
306 root
->commit_root
= NULL
;
307 root
->blocksize
= blocksize
;
309 root
->fs_info
= fs_info
;
310 root
->objectid
= objectid
;
311 root
->last_trans
= 0;
312 root
->highest_inode
= 0;
313 root
->last_inode_alloc
= 0;
314 memset(&root
->root_key
, 0, sizeof(root
->root_key
));
315 memset(&root
->root_item
, 0, sizeof(root
->root_item
));
319 static int find_and_setup_root(int blocksize
,
320 struct btrfs_root
*tree_root
,
321 struct btrfs_fs_info
*fs_info
,
323 struct btrfs_root
*root
)
327 __setup_root(blocksize
, root
, fs_info
, objectid
);
328 ret
= btrfs_find_last_root(tree_root
, objectid
,
329 &root
->root_item
, &root
->root_key
);
332 root
->node
= read_tree_block(root
,
333 btrfs_root_blocknr(&root
->root_item
));
338 struct btrfs_root
*btrfs_read_fs_root(struct btrfs_fs_info
*fs_info
,
339 struct btrfs_key
*location
)
341 struct btrfs_root
*root
;
342 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
343 struct btrfs_path
*path
;
344 struct btrfs_leaf
*l
;
348 printk("read_fs_root looking for %Lu %Lu %u\n", location
->objectid
, location
->offset
, location
->flags
);
349 root
= radix_tree_lookup(&fs_info
->fs_roots_radix
,
350 (unsigned long)location
->objectid
);
352 printk("found %p in cache\n", root
);
355 root
= kmalloc(sizeof(*root
), GFP_NOFS
);
358 return ERR_PTR(-ENOMEM
);
360 if (location
->offset
== (u64
)-1) {
361 ret
= find_and_setup_root(fs_info
->sb
->s_blocksize
,
362 fs_info
->tree_root
, fs_info
,
363 location
->objectid
, root
);
372 __setup_root(fs_info
->sb
->s_blocksize
, root
, fs_info
,
375 path
= btrfs_alloc_path();
377 ret
= btrfs_search_slot(NULL
, tree_root
, location
, path
, 0, 0);
379 printk("internal search_slot gives us %d\n", ret
);
384 l
= btrfs_buffer_leaf(path
->nodes
[0]);
385 memcpy(&root
->root_item
,
386 btrfs_item_ptr(l
, path
->slots
[0], struct btrfs_root_item
),
387 sizeof(root
->root_item
));
388 memcpy(&root
->root_key
, location
, sizeof(*location
));
391 btrfs_release_path(root
, path
);
392 btrfs_free_path(path
);
397 root
->node
= read_tree_block(root
,
398 btrfs_root_blocknr(&root
->root_item
));
401 printk("inserting %p\n", root
);
403 ret
= radix_tree_insert(&fs_info
->fs_roots_radix
,
404 (unsigned long)root
->root_key
.objectid
,
407 printk("radix_tree_insert gives us %d\n", ret
);
412 ret
= btrfs_find_highest_inode(root
, &highest_inode
);
414 root
->highest_inode
= highest_inode
;
415 root
->last_inode_alloc
= highest_inode
;
416 printk("highest inode is %Lu\n", highest_inode
);
418 printk("all worked\n");
422 static int btrfs_open_disk(struct btrfs_root
*root
, u64 device_id
,
423 u64 block_start
, u64 num_blocks
,
424 char *filename
, int name_len
)
427 struct block_device
*bdev
;
430 null_filename
= kmalloc(name_len
+ 1, GFP_NOFS
);
433 memcpy(null_filename
, filename
, name_len
);
434 null_filename
[name_len
] = '\0';
436 bdev
= open_bdev_excl(null_filename
, O_RDWR
, root
->fs_info
->sb
);
441 set_blocksize(bdev
, root
->fs_info
->sb
->s_blocksize
);
442 ret
= btrfs_insert_dev_radix(root
, bdev
, device_id
,
443 block_start
, num_blocks
);
447 kfree(null_filename
);
451 static int read_device_info(struct btrfs_root
*root
)
453 struct btrfs_path
*path
;
455 struct btrfs_key key
;
456 struct btrfs_leaf
*leaf
;
457 struct btrfs_device_item
*dev_item
;
461 root
= root
->fs_info
->dev_root
;
463 path
= btrfs_alloc_path();
469 btrfs_set_key_type(&key
, BTRFS_DEV_ITEM_KEY
);
471 mutex_lock(&root
->fs_info
->fs_mutex
);
472 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
473 leaf
= btrfs_buffer_leaf(path
->nodes
[0]);
474 nritems
= btrfs_header_nritems(&leaf
->header
);
476 slot
= path
->slots
[0];
477 if (slot
>= nritems
) {
478 ret
= btrfs_next_leaf(root
, path
);
481 leaf
= btrfs_buffer_leaf(path
->nodes
[0]);
482 nritems
= btrfs_header_nritems(&leaf
->header
);
483 slot
= path
->slots
[0];
485 btrfs_disk_key_to_cpu(&key
, &leaf
->items
[slot
].key
);
486 if (btrfs_key_type(&key
) != BTRFS_DEV_ITEM_KEY
) {
490 dev_item
= btrfs_item_ptr(leaf
, slot
, struct btrfs_device_item
);
491 printk("found key %Lu %Lu\n", key
.objectid
, key
.offset
);
492 if (btrfs_device_id(dev_item
) !=
493 btrfs_super_device_id(root
->fs_info
->disk_super
)) {
494 ret
= btrfs_open_disk(root
, btrfs_device_id(dev_item
),
495 key
.objectid
, key
.offset
,
496 (char *)(dev_item
+ 1),
497 btrfs_device_pathlen(dev_item
));
502 btrfs_free_path(path
);
503 mutex_unlock(&root
->fs_info
->fs_mutex
);
507 struct btrfs_root
*open_ctree(struct super_block
*sb
)
509 struct btrfs_root
*extent_root
= kmalloc(sizeof(struct btrfs_root
),
511 struct btrfs_root
*dev_root
= kmalloc(sizeof(struct btrfs_root
),
513 struct btrfs_root
*tree_root
= kmalloc(sizeof(struct btrfs_root
),
515 struct btrfs_fs_info
*fs_info
= kmalloc(sizeof(*fs_info
),
518 struct btrfs_super_block
*disk_super
;
519 struct dev_lookup
*dev_lookup
;
521 init_bit_radix(&fs_info
->pinned_radix
);
522 init_bit_radix(&fs_info
->pending_del_radix
);
523 INIT_RADIX_TREE(&fs_info
->fs_roots_radix
, GFP_NOFS
);
524 INIT_RADIX_TREE(&fs_info
->dev_radix
, GFP_NOFS
);
525 sb_set_blocksize(sb
, 4096);
526 fs_info
->running_transaction
= NULL
;
527 fs_info
->tree_root
= tree_root
;
528 fs_info
->extent_root
= extent_root
;
529 fs_info
->dev_root
= dev_root
;
531 fs_info
->btree_inode
= new_inode(sb
);
532 fs_info
->btree_inode
->i_ino
= 1;
533 fs_info
->btree_inode
->i_nlink
= 1;
534 fs_info
->btree_inode
->i_size
= sb
->s_bdev
->bd_inode
->i_size
;
535 fs_info
->btree_inode
->i_mapping
->a_ops
= &btree_aops
;
536 BTRFS_I(fs_info
->btree_inode
)->root
= tree_root
;
537 memset(&BTRFS_I(fs_info
->btree_inode
)->location
, 0,
538 sizeof(struct btrfs_key
));
539 insert_inode_hash(fs_info
->btree_inode
);
540 mapping_set_gfp_mask(fs_info
->btree_inode
->i_mapping
, GFP_NOFS
);
541 fs_info
->hash_tfm
= crypto_alloc_hash("sha256", 0, CRYPTO_ALG_ASYNC
);
542 spin_lock_init(&fs_info
->hash_lock
);
543 if (!fs_info
->hash_tfm
|| IS_ERR(fs_info
->hash_tfm
)) {
544 printk("failed to allocate sha256 hash\n");
547 mutex_init(&fs_info
->trans_mutex
);
548 mutex_init(&fs_info
->fs_mutex
);
549 memset(&fs_info
->current_insert
, 0, sizeof(fs_info
->current_insert
));
550 memset(&fs_info
->last_insert
, 0, sizeof(fs_info
->last_insert
));
552 __setup_root(sb
->s_blocksize
, dev_root
,
553 fs_info
, BTRFS_DEV_TREE_OBJECTID
);
555 __setup_root(sb
->s_blocksize
, tree_root
,
556 fs_info
, BTRFS_ROOT_TREE_OBJECTID
);
558 dev_lookup
= kmalloc(sizeof(*dev_lookup
), GFP_NOFS
);
559 dev_lookup
->block_start
= 0;
560 dev_lookup
->num_blocks
= (u32
)-2;
561 dev_lookup
->bdev
= sb
->s_bdev
;
562 dev_lookup
->device_id
= 0;
563 ret
= radix_tree_insert(&fs_info
->dev_radix
, (u32
)-2, dev_lookup
);
565 fs_info
->sb_buffer
= read_tree_block(tree_root
,
566 BTRFS_SUPER_INFO_OFFSET
/
569 if (!fs_info
->sb_buffer
)
571 disk_super
= (struct btrfs_super_block
*)fs_info
->sb_buffer
->b_data
;
572 if (!btrfs_super_root(disk_super
))
575 i_size_write(fs_info
->btree_inode
,
576 btrfs_super_total_blocks(disk_super
) <<
577 fs_info
->btree_inode
->i_blkbits
);
579 radix_tree_delete(&fs_info
->dev_radix
, (u32
)-2);
580 dev_lookup
->block_start
= btrfs_super_device_block_start(disk_super
);
581 dev_lookup
->num_blocks
= btrfs_super_device_num_blocks(disk_super
);
582 dev_lookup
->device_id
= btrfs_super_device_id(disk_super
);
584 ret
= radix_tree_insert(&fs_info
->dev_radix
,
585 dev_lookup
->block_start
+
586 dev_lookup
->num_blocks
- 1, dev_lookup
);
589 fs_info
->disk_super
= disk_super
;
591 dev_root
->node
= read_tree_block(tree_root
,
592 btrfs_super_device_root(disk_super
));
594 ret
= read_device_info(dev_root
);
597 tree_root
->node
= read_tree_block(tree_root
,
598 btrfs_super_root(disk_super
));
599 BUG_ON(!tree_root
->node
);
601 mutex_lock(&fs_info
->fs_mutex
);
602 ret
= find_and_setup_root(sb
->s_blocksize
, tree_root
, fs_info
,
603 BTRFS_EXTENT_TREE_OBJECTID
, extent_root
);
606 fs_info
->generation
= btrfs_super_generation(disk_super
) + 1;
607 memset(&fs_info
->kobj
, 0, sizeof(fs_info
->kobj
));
608 kobj_set_kset_s(fs_info
, btrfs_subsys
);
609 kobject_set_name(&fs_info
->kobj
, "%s", sb
->s_id
);
610 kobject_register(&fs_info
->kobj
);
611 mutex_unlock(&fs_info
->fs_mutex
);
615 int write_ctree_super(struct btrfs_trans_handle
*trans
, struct btrfs_root
618 struct buffer_head
*bh
= root
->fs_info
->sb_buffer
;
620 btrfs_set_super_root(root
->fs_info
->disk_super
,
621 bh_blocknr(root
->fs_info
->tree_root
->node
));
623 WARN_ON(atomic_read(&bh
->b_count
) < 1);
624 clear_buffer_dirty(bh
);
625 csum_tree_block(root
, bh
, 0);
626 bh
->b_end_io
= end_buffer_write_sync
;
628 submit_bh(WRITE
, bh
);
630 if (!buffer_uptodate(bh
)) {
637 static int free_fs_root(struct btrfs_fs_info
*fs_info
, struct btrfs_root
*root
)
639 radix_tree_delete(&fs_info
->fs_roots_radix
,
640 (unsigned long)root
->root_key
.objectid
);
645 if (root
->commit_root
)
646 brelse(root
->commit_root
);
651 int del_fs_roots(struct btrfs_fs_info
*fs_info
)
654 struct btrfs_root
*gang
[8];
658 ret
= radix_tree_gang_lookup(&fs_info
->fs_roots_radix
,
663 for (i
= 0; i
< ret
; i
++)
664 free_fs_root(fs_info
, gang
[i
]);
669 static int free_dev_radix(struct btrfs_fs_info
*fs_info
)
671 struct dev_lookup
*lookup
[8];
672 struct block_device
*super_bdev
= fs_info
->sb
->s_bdev
;
676 ret
= radix_tree_gang_lookup(&fs_info
->dev_radix
,
681 for (i
= 0; i
< ret
; i
++) {
682 if (lookup
[i
]->bdev
!= super_bdev
)
683 close_bdev_excl(lookup
[i
]->bdev
);
684 radix_tree_delete(&fs_info
->dev_radix
,
685 lookup
[i
]->block_start
+
686 lookup
[i
]->num_blocks
- 1);
693 int close_ctree(struct btrfs_root
*root
)
696 struct btrfs_trans_handle
*trans
;
697 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
699 mutex_lock(&fs_info
->fs_mutex
);
700 trans
= btrfs_start_transaction(root
, 1);
701 btrfs_commit_transaction(trans
, root
);
702 /* run commit again to drop the original snapshot */
703 trans
= btrfs_start_transaction(root
, 1);
704 btrfs_commit_transaction(trans
, root
);
705 ret
= btrfs_write_and_wait_transaction(NULL
, root
);
707 write_ctree_super(NULL
, root
);
708 mutex_unlock(&fs_info
->fs_mutex
);
710 if (fs_info
->extent_root
->node
)
711 btrfs_block_release(fs_info
->extent_root
,
712 fs_info
->extent_root
->node
);
713 if (fs_info
->dev_root
->node
)
714 btrfs_block_release(fs_info
->dev_root
,
715 fs_info
->dev_root
->node
);
716 if (fs_info
->tree_root
->node
)
717 btrfs_block_release(fs_info
->tree_root
,
718 fs_info
->tree_root
->node
);
719 btrfs_block_release(root
, fs_info
->sb_buffer
);
720 crypto_free_hash(fs_info
->hash_tfm
);
721 truncate_inode_pages(fs_info
->btree_inode
->i_mapping
, 0);
722 iput(fs_info
->btree_inode
);
724 free_dev_radix(fs_info
);
725 del_fs_roots(fs_info
);
726 kfree(fs_info
->extent_root
);
727 kfree(fs_info
->tree_root
);
728 kobject_unregister(&fs_info
->kobj
);
732 void btrfs_block_release(struct btrfs_root
*root
, struct buffer_head
*buf
)