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>
8 #include <linux/writeback.h>
11 #include "transaction.h"
12 #include "btrfs_inode.h"
14 u64
bh_blocknr(struct buffer_head
*bh
)
19 static int check_tree_block(struct btrfs_root
*root
, struct buffer_head
*buf
)
21 struct btrfs_node
*node
= btrfs_buffer_node(buf
);
22 if (bh_blocknr(buf
) != btrfs_header_blocknr(&node
->header
)) {
23 printk(KERN_CRIT
"bh_blocknr(buf) is %Lu, header is %Lu\n",
24 bh_blocknr(buf
), btrfs_header_blocknr(&node
->header
));
30 struct buffer_head
*btrfs_find_tree_block(struct btrfs_root
*root
, u64 blocknr
)
32 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
33 int blockbits
= root
->fs_info
->sb
->s_blocksize_bits
;
34 unsigned long index
= blocknr
>> (PAGE_CACHE_SHIFT
- blockbits
);
36 struct buffer_head
*bh
;
37 struct buffer_head
*head
;
38 struct buffer_head
*ret
= NULL
;
41 page
= find_lock_page(mapping
, index
);
45 if (!page_has_buffers(page
))
48 head
= page_buffers(page
);
51 if (buffer_mapped(bh
) && bh_blocknr(bh
) == blocknr
) {
60 page_cache_release(page
);
64 int btrfs_map_bh_to_logical(struct btrfs_root
*root
, struct buffer_head
*bh
,
70 set_buffer_mapped(bh
);
72 map_bh(bh
, root
->fs_info
->sb
, logical
);
77 struct buffer_head
*btrfs_find_create_tree_block(struct btrfs_root
*root
,
80 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
81 int blockbits
= root
->fs_info
->sb
->s_blocksize_bits
;
82 unsigned long index
= blocknr
>> (PAGE_CACHE_SHIFT
- blockbits
);
84 struct buffer_head
*bh
;
85 struct buffer_head
*head
;
86 struct buffer_head
*ret
= NULL
;
88 u64 first_block
= index
<< (PAGE_CACHE_SHIFT
- blockbits
);
90 page
= grab_cache_page(mapping
, index
);
94 if (!page_has_buffers(page
))
95 create_empty_buffers(page
, root
->fs_info
->sb
->s_blocksize
, 0);
96 head
= page_buffers(page
);
99 if (!buffer_mapped(bh
)) {
100 err
= btrfs_map_bh_to_logical(root
, bh
, first_block
);
103 if (bh_blocknr(bh
) == blocknr
) {
108 bh
= bh
->b_this_page
;
110 } while (bh
!= head
);
115 page_cache_release(page
);
119 static int btree_get_block(struct inode
*inode
, sector_t iblock
,
120 struct buffer_head
*bh
, int create
)
123 struct btrfs_root
*root
= BTRFS_I(bh
->b_page
->mapping
->host
)->root
;
124 err
= btrfs_map_bh_to_logical(root
, bh
, iblock
);
128 int btrfs_csum_data(struct btrfs_root
* root
, char *data
, size_t len
,
131 struct scatterlist sg
;
132 struct crypto_hash
*tfm
= root
->fs_info
->hash_tfm
;
133 struct hash_desc desc
;
138 sg_init_one(&sg
, data
, len
);
139 spin_lock(&root
->fs_info
->hash_lock
);
140 ret
= crypto_hash_digest(&desc
, &sg
, 1, result
);
141 spin_unlock(&root
->fs_info
->hash_lock
);
143 printk("digest failed\n");
147 static int csum_tree_block(struct btrfs_root
*root
, struct buffer_head
*bh
,
150 char result
[BTRFS_CRC32_SIZE
];
152 struct btrfs_node
*node
;
154 ret
= btrfs_csum_data(root
, bh
->b_data
+ BTRFS_CSUM_SIZE
,
155 bh
->b_size
- BTRFS_CSUM_SIZE
, result
);
159 if (memcmp(bh
->b_data
, result
, BTRFS_CRC32_SIZE
)) {
160 printk("checksum verify failed on %Lu\n",
165 node
= btrfs_buffer_node(bh
);
166 memcpy(node
->header
.csum
, result
, BTRFS_CRC32_SIZE
);
171 static int btree_writepage(struct page
*page
, struct writeback_control
*wbc
)
173 struct buffer_head
*bh
;
174 struct btrfs_root
*root
= BTRFS_I(page
->mapping
->host
)->root
;
175 struct buffer_head
*head
;
176 if (!page_has_buffers(page
)) {
177 create_empty_buffers(page
, root
->fs_info
->sb
->s_blocksize
,
178 (1 << BH_Dirty
)|(1 << BH_Uptodate
));
180 head
= page_buffers(page
);
183 if (buffer_dirty(bh
))
184 csum_tree_block(root
, bh
, 0);
185 bh
= bh
->b_this_page
;
186 } while (bh
!= head
);
187 return block_write_full_page(page
, btree_get_block
, wbc
);
190 static int btree_readpage(struct file
* file
, struct page
* page
)
192 return block_read_full_page(page
, btree_get_block
);
195 static struct address_space_operations btree_aops
= {
196 .readpage
= btree_readpage
,
197 .writepage
= btree_writepage
,
198 .sync_page
= block_sync_page
,
201 int readahead_tree_block(struct btrfs_root
*root
, u64 blocknr
)
203 struct buffer_head
*bh
= NULL
;
206 bh
= btrfs_find_create_tree_block(root
, blocknr
);
209 if (buffer_uptodate(bh
)) {
213 if (test_set_buffer_locked(bh
)) {
217 if (!buffer_uptodate(bh
)) {
219 bh
->b_end_io
= end_buffer_read_sync
;
230 struct buffer_head
*read_tree_block(struct btrfs_root
*root
, u64 blocknr
)
232 struct buffer_head
*bh
= NULL
;
234 bh
= btrfs_find_create_tree_block(root
, blocknr
);
237 if (buffer_uptodate(bh
))
240 if (!buffer_uptodate(bh
)) {
242 bh
->b_end_io
= end_buffer_read_sync
;
245 if (!buffer_uptodate(bh
))
251 if (!buffer_checked(bh
)) {
252 csum_tree_block(root
, bh
, 1);
253 set_buffer_checked(bh
);
255 if (check_tree_block(root
, bh
))
263 int dirty_tree_block(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
264 struct buffer_head
*buf
)
266 WARN_ON(atomic_read(&buf
->b_count
) == 0);
267 mark_buffer_dirty(buf
);
271 int clean_tree_block(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
272 struct buffer_head
*buf
)
274 WARN_ON(atomic_read(&buf
->b_count
) == 0);
275 clear_buffer_dirty(buf
);
279 static int __setup_root(int blocksize
,
280 struct btrfs_root
*root
,
281 struct btrfs_fs_info
*fs_info
,
286 root
->commit_root
= NULL
;
287 root
->blocksize
= blocksize
;
289 root
->fs_info
= fs_info
;
290 root
->objectid
= objectid
;
291 root
->last_trans
= 0;
292 root
->highest_inode
= 0;
293 root
->last_inode_alloc
= 0;
294 memset(&root
->root_key
, 0, sizeof(root
->root_key
));
295 memset(&root
->root_item
, 0, sizeof(root
->root_item
));
296 root
->root_key
.objectid
= objectid
;
300 static int find_and_setup_root(int blocksize
,
301 struct btrfs_root
*tree_root
,
302 struct btrfs_fs_info
*fs_info
,
304 struct btrfs_root
*root
)
308 __setup_root(blocksize
, root
, fs_info
, objectid
);
309 ret
= btrfs_find_last_root(tree_root
, objectid
,
310 &root
->root_item
, &root
->root_key
);
313 root
->node
= read_tree_block(root
,
314 btrfs_root_blocknr(&root
->root_item
));
319 struct btrfs_root
*btrfs_read_fs_root(struct btrfs_fs_info
*fs_info
,
320 struct btrfs_key
*location
)
322 struct btrfs_root
*root
;
323 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
324 struct btrfs_path
*path
;
325 struct btrfs_leaf
*l
;
329 root
= radix_tree_lookup(&fs_info
->fs_roots_radix
,
330 (unsigned long)location
->objectid
);
333 root
= kmalloc(sizeof(*root
), GFP_NOFS
);
335 return ERR_PTR(-ENOMEM
);
336 if (location
->offset
== (u64
)-1) {
337 ret
= find_and_setup_root(fs_info
->sb
->s_blocksize
,
338 fs_info
->tree_root
, fs_info
,
339 location
->objectid
, root
);
347 __setup_root(fs_info
->sb
->s_blocksize
, root
, fs_info
,
350 path
= btrfs_alloc_path();
352 ret
= btrfs_search_slot(NULL
, tree_root
, location
, path
, 0, 0);
358 l
= btrfs_buffer_leaf(path
->nodes
[0]);
359 memcpy(&root
->root_item
,
360 btrfs_item_ptr(l
, path
->slots
[0], struct btrfs_root_item
),
361 sizeof(root
->root_item
));
362 memcpy(&root
->root_key
, location
, sizeof(*location
));
365 btrfs_release_path(root
, path
);
366 btrfs_free_path(path
);
371 root
->node
= read_tree_block(root
,
372 btrfs_root_blocknr(&root
->root_item
));
376 ret
= radix_tree_insert(&fs_info
->fs_roots_radix
,
377 (unsigned long)root
->root_key
.objectid
,
384 ret
= btrfs_find_highest_inode(root
, &highest_inode
);
386 root
->highest_inode
= highest_inode
;
387 root
->last_inode_alloc
= highest_inode
;
392 struct btrfs_root
*open_ctree(struct super_block
*sb
)
394 struct btrfs_root
*extent_root
= kmalloc(sizeof(struct btrfs_root
),
396 struct btrfs_root
*tree_root
= kmalloc(sizeof(struct btrfs_root
),
398 struct btrfs_fs_info
*fs_info
= kmalloc(sizeof(*fs_info
),
401 struct btrfs_super_block
*disk_super
;
403 init_bit_radix(&fs_info
->pinned_radix
);
404 init_bit_radix(&fs_info
->pending_del_radix
);
405 init_bit_radix(&fs_info
->extent_map_radix
);
406 INIT_RADIX_TREE(&fs_info
->fs_roots_radix
, GFP_NOFS
);
407 INIT_RADIX_TREE(&fs_info
->block_group_radix
, GFP_KERNEL
);
408 INIT_RADIX_TREE(&fs_info
->block_group_data_radix
, GFP_KERNEL
);
409 INIT_LIST_HEAD(&fs_info
->trans_list
);
410 INIT_LIST_HEAD(&fs_info
->dead_roots
);
411 sb_set_blocksize(sb
, 4096);
412 fs_info
->running_transaction
= NULL
;
413 fs_info
->tree_root
= tree_root
;
414 fs_info
->extent_root
= extent_root
;
416 fs_info
->btree_inode
= new_inode(sb
);
417 fs_info
->btree_inode
->i_ino
= 1;
418 fs_info
->btree_inode
->i_nlink
= 1;
419 fs_info
->btree_inode
->i_size
= sb
->s_bdev
->bd_inode
->i_size
;
420 fs_info
->btree_inode
->i_mapping
->a_ops
= &btree_aops
;
421 fs_info
->do_barriers
= 1;
422 fs_info
->extent_tree_insert_nr
= 0;
423 fs_info
->extent_tree_prealloc_nr
= 0;
424 fs_info
->closing
= 0;
426 INIT_DELAYED_WORK(&fs_info
->trans_work
, btrfs_transaction_cleaner
);
427 BTRFS_I(fs_info
->btree_inode
)->root
= tree_root
;
428 memset(&BTRFS_I(fs_info
->btree_inode
)->location
, 0,
429 sizeof(struct btrfs_key
));
430 insert_inode_hash(fs_info
->btree_inode
);
431 mapping_set_gfp_mask(fs_info
->btree_inode
->i_mapping
, GFP_NOFS
);
432 fs_info
->hash_tfm
= crypto_alloc_hash("crc32c", 0, CRYPTO_ALG_ASYNC
);
433 spin_lock_init(&fs_info
->hash_lock
);
434 if (!fs_info
->hash_tfm
|| IS_ERR(fs_info
->hash_tfm
)) {
435 printk("failed to allocate digest hash\n");
438 mutex_init(&fs_info
->trans_mutex
);
439 mutex_init(&fs_info
->fs_mutex
);
441 __setup_root(sb
->s_blocksize
, tree_root
,
442 fs_info
, BTRFS_ROOT_TREE_OBJECTID
);
444 fs_info
->sb_buffer
= read_tree_block(tree_root
,
445 BTRFS_SUPER_INFO_OFFSET
/
448 if (!fs_info
->sb_buffer
)
450 disk_super
= (struct btrfs_super_block
*)fs_info
->sb_buffer
->b_data
;
451 if (!btrfs_super_root(disk_super
))
454 i_size_write(fs_info
->btree_inode
,
455 btrfs_super_total_blocks(disk_super
) <<
456 fs_info
->btree_inode
->i_blkbits
);
458 fs_info
->disk_super
= disk_super
;
459 tree_root
->node
= read_tree_block(tree_root
,
460 btrfs_super_root(disk_super
));
461 BUG_ON(!tree_root
->node
);
463 mutex_lock(&fs_info
->fs_mutex
);
464 ret
= find_and_setup_root(sb
->s_blocksize
, tree_root
, fs_info
,
465 BTRFS_EXTENT_TREE_OBJECTID
, extent_root
);
468 btrfs_read_block_groups(extent_root
);
470 fs_info
->generation
= btrfs_super_generation(disk_super
) + 1;
471 mutex_unlock(&fs_info
->fs_mutex
);
475 int write_ctree_super(struct btrfs_trans_handle
*trans
, struct btrfs_root
479 struct buffer_head
*bh
= root
->fs_info
->sb_buffer
;
481 btrfs_set_super_root(root
->fs_info
->disk_super
,
482 bh_blocknr(root
->fs_info
->tree_root
->node
));
484 WARN_ON(atomic_read(&bh
->b_count
) < 1);
485 clear_buffer_dirty(bh
);
486 csum_tree_block(root
, bh
, 0);
487 bh
->b_end_io
= end_buffer_write_sync
;
489 if (root
->fs_info
->do_barriers
)
490 ret
= submit_bh(WRITE_BARRIER
, bh
);
492 ret
= submit_bh(WRITE
, bh
);
493 if (ret
== -EOPNOTSUPP
) {
494 set_buffer_uptodate(bh
);
495 root
->fs_info
->do_barriers
= 0;
496 ret
= submit_bh(WRITE
, bh
);
499 if (!buffer_uptodate(bh
)) {
506 static int free_fs_root(struct btrfs_fs_info
*fs_info
, struct btrfs_root
*root
)
508 radix_tree_delete(&fs_info
->fs_roots_radix
,
509 (unsigned long)root
->root_key
.objectid
);
514 if (root
->commit_root
)
515 brelse(root
->commit_root
);
520 static int del_fs_roots(struct btrfs_fs_info
*fs_info
)
523 struct btrfs_root
*gang
[8];
527 ret
= radix_tree_gang_lookup(&fs_info
->fs_roots_radix
,
532 for (i
= 0; i
< ret
; i
++)
533 free_fs_root(fs_info
, gang
[i
]);
538 int close_ctree(struct btrfs_root
*root
)
541 struct btrfs_trans_handle
*trans
;
542 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
544 fs_info
->closing
= 1;
545 btrfs_transaction_flush_work(root
);
546 mutex_lock(&fs_info
->fs_mutex
);
547 trans
= btrfs_start_transaction(root
, 1);
548 btrfs_commit_transaction(trans
, root
);
549 /* run commit again to drop the original snapshot */
550 trans
= btrfs_start_transaction(root
, 1);
551 btrfs_commit_transaction(trans
, root
);
552 ret
= btrfs_write_and_wait_transaction(NULL
, root
);
554 write_ctree_super(NULL
, root
);
555 mutex_unlock(&fs_info
->fs_mutex
);
557 if (fs_info
->extent_root
->node
)
558 btrfs_block_release(fs_info
->extent_root
,
559 fs_info
->extent_root
->node
);
560 if (fs_info
->tree_root
->node
)
561 btrfs_block_release(fs_info
->tree_root
,
562 fs_info
->tree_root
->node
);
563 btrfs_block_release(root
, fs_info
->sb_buffer
);
564 crypto_free_hash(fs_info
->hash_tfm
);
565 truncate_inode_pages(fs_info
->btree_inode
->i_mapping
, 0);
566 iput(fs_info
->btree_inode
);
568 btrfs_free_block_groups(root
->fs_info
);
569 del_fs_roots(fs_info
);
570 kfree(fs_info
->extent_root
);
571 kfree(fs_info
->tree_root
);
575 void btrfs_block_release(struct btrfs_root
*root
, struct buffer_head
*buf
)
580 void btrfs_btree_balance_dirty(struct btrfs_root
*root
)
582 balance_dirty_pages_ratelimited(root
->fs_info
->btree_inode
->i_mapping
);