2 * Copyright (C) 2007 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/module.h>
21 #include <linux/blkdev.h>
22 #include <linux/crypto.h>
23 #include <linux/scatterlist.h>
24 #include <linux/swap.h>
25 #include <linux/radix-tree.h>
26 #include <linux/writeback.h>
29 #include "transaction.h"
30 #include "btrfs_inode.h"
32 u64
bh_blocknr(struct buffer_head
*bh
)
37 static int check_tree_block(struct btrfs_root
*root
, struct buffer_head
*buf
)
39 struct btrfs_node
*node
= btrfs_buffer_node(buf
);
40 if (bh_blocknr(buf
) != btrfs_header_blocknr(&node
->header
)) {
41 printk(KERN_CRIT
"bh_blocknr(buf) is %llu, header is %llu\n",
42 (unsigned long long)bh_blocknr(buf
),
43 (unsigned long long)btrfs_header_blocknr(&node
->header
));
49 struct buffer_head
*btrfs_find_tree_block(struct btrfs_root
*root
, u64 blocknr
)
51 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
52 int blockbits
= root
->fs_info
->sb
->s_blocksize_bits
;
53 unsigned long index
= blocknr
>> (PAGE_CACHE_SHIFT
- blockbits
);
55 struct buffer_head
*bh
;
56 struct buffer_head
*head
;
57 struct buffer_head
*ret
= NULL
;
60 page
= find_lock_page(mapping
, index
);
64 if (!page_has_buffers(page
))
67 head
= page_buffers(page
);
70 if (buffer_mapped(bh
) && bh_blocknr(bh
) == blocknr
) {
79 page_cache_release(page
);
83 int btrfs_map_bh_to_logical(struct btrfs_root
*root
, struct buffer_head
*bh
,
89 set_buffer_mapped(bh
);
91 map_bh(bh
, root
->fs_info
->sb
, logical
);
96 struct buffer_head
*btrfs_find_create_tree_block(struct btrfs_root
*root
,
99 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
100 int blockbits
= root
->fs_info
->sb
->s_blocksize_bits
;
101 unsigned long index
= blocknr
>> (PAGE_CACHE_SHIFT
- blockbits
);
103 struct buffer_head
*bh
;
104 struct buffer_head
*head
;
105 struct buffer_head
*ret
= NULL
;
107 u64 first_block
= index
<< (PAGE_CACHE_SHIFT
- blockbits
);
109 page
= find_or_create_page(mapping
, index
, GFP_NOFS
);
113 if (!page_has_buffers(page
))
114 create_empty_buffers(page
, root
->fs_info
->sb
->s_blocksize
, 0);
115 head
= page_buffers(page
);
118 if (!buffer_mapped(bh
)) {
119 err
= btrfs_map_bh_to_logical(root
, bh
, first_block
);
122 if (bh_blocknr(bh
) == blocknr
) {
127 bh
= bh
->b_this_page
;
129 } while (bh
!= head
);
134 page_cache_release(page
);
138 static int btree_get_block(struct inode
*inode
, sector_t iblock
,
139 struct buffer_head
*bh
, int create
)
142 struct btrfs_root
*root
= BTRFS_I(bh
->b_page
->mapping
->host
)->root
;
143 err
= btrfs_map_bh_to_logical(root
, bh
, iblock
);
147 int btrfs_csum_data(struct btrfs_root
* root
, char *data
, size_t len
,
150 struct scatterlist sg
;
151 struct crypto_hash
*tfm
= root
->fs_info
->hash_tfm
;
152 struct hash_desc desc
;
157 sg_init_one(&sg
, data
, len
);
158 spin_lock(&root
->fs_info
->hash_lock
);
159 ret
= crypto_hash_digest(&desc
, &sg
, 1, result
);
160 spin_unlock(&root
->fs_info
->hash_lock
);
162 printk("digest failed\n");
166 static int csum_tree_block(struct btrfs_root
*root
, struct buffer_head
*bh
,
169 char result
[BTRFS_CRC32_SIZE
];
171 struct btrfs_node
*node
;
173 ret
= btrfs_csum_data(root
, bh
->b_data
+ BTRFS_CSUM_SIZE
,
174 bh
->b_size
- BTRFS_CSUM_SIZE
, result
);
178 if (memcmp(bh
->b_data
, result
, BTRFS_CRC32_SIZE
)) {
179 printk("btrfs: %s checksum verify failed on %llu\n",
180 root
->fs_info
->sb
->s_id
,
181 (unsigned long long)bh_blocknr(bh
));
185 node
= btrfs_buffer_node(bh
);
186 memcpy(node
->header
.csum
, result
, BTRFS_CRC32_SIZE
);
191 static int btree_writepage(struct page
*page
, struct writeback_control
*wbc
)
193 struct buffer_head
*bh
;
194 struct btrfs_root
*root
= BTRFS_I(page
->mapping
->host
)->root
;
195 struct buffer_head
*head
;
196 if (!page_has_buffers(page
)) {
197 create_empty_buffers(page
, root
->fs_info
->sb
->s_blocksize
,
198 (1 << BH_Dirty
)|(1 << BH_Uptodate
));
200 head
= page_buffers(page
);
203 if (buffer_dirty(bh
))
204 csum_tree_block(root
, bh
, 0);
205 bh
= bh
->b_this_page
;
206 } while (bh
!= head
);
207 return block_write_full_page(page
, btree_get_block
, wbc
);
210 static int btree_readpage(struct file
* file
, struct page
* page
)
212 return block_read_full_page(page
, btree_get_block
);
215 static struct address_space_operations btree_aops
= {
216 .readpage
= btree_readpage
,
217 .writepage
= btree_writepage
,
218 .sync_page
= block_sync_page
,
221 int readahead_tree_block(struct btrfs_root
*root
, u64 blocknr
)
223 struct buffer_head
*bh
= NULL
;
226 bh
= btrfs_find_create_tree_block(root
, blocknr
);
229 if (buffer_uptodate(bh
)) {
233 if (test_set_buffer_locked(bh
)) {
237 if (!buffer_uptodate(bh
)) {
239 bh
->b_end_io
= end_buffer_read_sync
;
250 struct buffer_head
*read_tree_block(struct btrfs_root
*root
, u64 blocknr
)
252 struct buffer_head
*bh
= NULL
;
254 bh
= btrfs_find_create_tree_block(root
, blocknr
);
257 if (buffer_uptodate(bh
))
260 if (!buffer_uptodate(bh
)) {
262 bh
->b_end_io
= end_buffer_read_sync
;
265 if (!buffer_uptodate(bh
))
271 if (!buffer_checked(bh
)) {
272 csum_tree_block(root
, bh
, 1);
273 set_buffer_checked(bh
);
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
));
316 root
->root_key
.objectid
= objectid
;
320 static int find_and_setup_root(int blocksize
,
321 struct btrfs_root
*tree_root
,
322 struct btrfs_fs_info
*fs_info
,
324 struct btrfs_root
*root
)
328 __setup_root(blocksize
, root
, fs_info
, objectid
);
329 ret
= btrfs_find_last_root(tree_root
, objectid
,
330 &root
->root_item
, &root
->root_key
);
333 root
->node
= read_tree_block(root
,
334 btrfs_root_blocknr(&root
->root_item
));
339 struct btrfs_root
*btrfs_read_fs_root(struct btrfs_fs_info
*fs_info
,
340 struct btrfs_key
*location
)
342 struct btrfs_root
*root
;
343 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
344 struct btrfs_path
*path
;
345 struct btrfs_leaf
*l
;
349 root
= radix_tree_lookup(&fs_info
->fs_roots_radix
,
350 (unsigned long)location
->objectid
);
353 root
= kmalloc(sizeof(*root
), GFP_NOFS
);
355 return ERR_PTR(-ENOMEM
);
356 if (location
->offset
== (u64
)-1) {
357 ret
= find_and_setup_root(fs_info
->sb
->s_blocksize
,
358 fs_info
->tree_root
, fs_info
,
359 location
->objectid
, root
);
367 __setup_root(fs_info
->sb
->s_blocksize
, root
, fs_info
,
370 path
= btrfs_alloc_path();
372 ret
= btrfs_search_slot(NULL
, tree_root
, location
, path
, 0, 0);
378 l
= btrfs_buffer_leaf(path
->nodes
[0]);
379 memcpy(&root
->root_item
,
380 btrfs_item_ptr(l
, path
->slots
[0], struct btrfs_root_item
),
381 sizeof(root
->root_item
));
382 memcpy(&root
->root_key
, location
, sizeof(*location
));
385 btrfs_release_path(root
, path
);
386 btrfs_free_path(path
);
391 root
->node
= read_tree_block(root
,
392 btrfs_root_blocknr(&root
->root_item
));
396 ret
= radix_tree_insert(&fs_info
->fs_roots_radix
,
397 (unsigned long)root
->root_key
.objectid
,
404 ret
= btrfs_find_highest_inode(root
, &highest_inode
);
406 root
->highest_inode
= highest_inode
;
407 root
->last_inode_alloc
= highest_inode
;
412 struct btrfs_root
*open_ctree(struct super_block
*sb
)
414 struct btrfs_root
*extent_root
= kmalloc(sizeof(struct btrfs_root
),
416 struct btrfs_root
*tree_root
= kmalloc(sizeof(struct btrfs_root
),
418 struct btrfs_fs_info
*fs_info
= kmalloc(sizeof(*fs_info
),
422 struct btrfs_super_block
*disk_super
;
424 if (!extent_root
|| !tree_root
|| !fs_info
) {
428 init_bit_radix(&fs_info
->pinned_radix
);
429 init_bit_radix(&fs_info
->pending_del_radix
);
430 init_bit_radix(&fs_info
->extent_map_radix
);
431 INIT_RADIX_TREE(&fs_info
->fs_roots_radix
, GFP_NOFS
);
432 INIT_RADIX_TREE(&fs_info
->block_group_radix
, GFP_KERNEL
);
433 INIT_RADIX_TREE(&fs_info
->block_group_data_radix
, GFP_KERNEL
);
434 INIT_LIST_HEAD(&fs_info
->trans_list
);
435 INIT_LIST_HEAD(&fs_info
->dead_roots
);
436 sb_set_blocksize(sb
, 4096);
437 fs_info
->running_transaction
= NULL
;
438 fs_info
->tree_root
= tree_root
;
439 fs_info
->extent_root
= extent_root
;
441 fs_info
->btree_inode
= new_inode(sb
);
442 fs_info
->btree_inode
->i_ino
= 1;
443 fs_info
->btree_inode
->i_nlink
= 1;
444 fs_info
->btree_inode
->i_size
= sb
->s_bdev
->bd_inode
->i_size
;
445 fs_info
->btree_inode
->i_mapping
->a_ops
= &btree_aops
;
446 fs_info
->do_barriers
= 1;
447 fs_info
->extent_tree_insert_nr
= 0;
448 fs_info
->extent_tree_prealloc_nr
= 0;
449 fs_info
->closing
= 0;
451 INIT_DELAYED_WORK(&fs_info
->trans_work
, btrfs_transaction_cleaner
);
452 BTRFS_I(fs_info
->btree_inode
)->root
= tree_root
;
453 memset(&BTRFS_I(fs_info
->btree_inode
)->location
, 0,
454 sizeof(struct btrfs_key
));
455 insert_inode_hash(fs_info
->btree_inode
);
456 mapping_set_gfp_mask(fs_info
->btree_inode
->i_mapping
, GFP_NOFS
);
457 fs_info
->hash_tfm
= crypto_alloc_hash("crc32c", 0, CRYPTO_ALG_ASYNC
);
458 spin_lock_init(&fs_info
->hash_lock
);
460 if (!fs_info
->hash_tfm
|| IS_ERR(fs_info
->hash_tfm
)) {
461 printk("btrfs: failed hash setup, modprobe cryptomgr?\n");
465 mutex_init(&fs_info
->trans_mutex
);
466 mutex_init(&fs_info
->fs_mutex
);
468 __setup_root(sb
->s_blocksize
, tree_root
,
469 fs_info
, BTRFS_ROOT_TREE_OBJECTID
);
471 fs_info
->sb_buffer
= read_tree_block(tree_root
,
472 BTRFS_SUPER_INFO_OFFSET
/
475 if (!fs_info
->sb_buffer
)
477 disk_super
= (struct btrfs_super_block
*)fs_info
->sb_buffer
->b_data
;
479 if (!btrfs_super_root(disk_super
))
482 i_size_write(fs_info
->btree_inode
,
483 btrfs_super_total_blocks(disk_super
) <<
484 fs_info
->btree_inode
->i_blkbits
);
486 fs_info
->disk_super
= disk_super
;
488 if (strncmp((char *)(&disk_super
->magic
), BTRFS_MAGIC
,
489 sizeof(disk_super
->magic
))) {
490 printk("btrfs: valid FS not found on %s\n", sb
->s_id
);
493 tree_root
->node
= read_tree_block(tree_root
,
494 btrfs_super_root(disk_super
));
495 if (!tree_root
->node
)
498 mutex_lock(&fs_info
->fs_mutex
);
499 ret
= find_and_setup_root(sb
->s_blocksize
, tree_root
, fs_info
,
500 BTRFS_EXTENT_TREE_OBJECTID
, extent_root
);
502 mutex_unlock(&fs_info
->fs_mutex
);
506 btrfs_read_block_groups(extent_root
);
508 fs_info
->generation
= btrfs_super_generation(disk_super
) + 1;
509 mutex_unlock(&fs_info
->fs_mutex
);
513 btrfs_block_release(tree_root
, tree_root
->node
);
515 btrfs_block_release(tree_root
, fs_info
->sb_buffer
);
517 iput(fs_info
->btree_inode
);
525 int write_ctree_super(struct btrfs_trans_handle
*trans
, struct btrfs_root
529 struct buffer_head
*bh
= root
->fs_info
->sb_buffer
;
531 btrfs_set_super_root(root
->fs_info
->disk_super
,
532 bh_blocknr(root
->fs_info
->tree_root
->node
));
534 WARN_ON(atomic_read(&bh
->b_count
) < 1);
535 clear_buffer_dirty(bh
);
536 csum_tree_block(root
, bh
, 0);
537 bh
->b_end_io
= end_buffer_write_sync
;
539 if (root
->fs_info
->do_barriers
)
540 ret
= submit_bh(WRITE_BARRIER
, bh
);
542 ret
= submit_bh(WRITE
, bh
);
543 if (ret
== -EOPNOTSUPP
) {
544 set_buffer_uptodate(bh
);
545 root
->fs_info
->do_barriers
= 0;
546 ret
= submit_bh(WRITE
, bh
);
549 if (!buffer_uptodate(bh
)) {
556 static int free_fs_root(struct btrfs_fs_info
*fs_info
, struct btrfs_root
*root
)
558 radix_tree_delete(&fs_info
->fs_roots_radix
,
559 (unsigned long)root
->root_key
.objectid
);
564 if (root
->commit_root
)
565 brelse(root
->commit_root
);
570 static int del_fs_roots(struct btrfs_fs_info
*fs_info
)
573 struct btrfs_root
*gang
[8];
577 ret
= radix_tree_gang_lookup(&fs_info
->fs_roots_radix
,
582 for (i
= 0; i
< ret
; i
++)
583 free_fs_root(fs_info
, gang
[i
]);
588 int close_ctree(struct btrfs_root
*root
)
591 struct btrfs_trans_handle
*trans
;
592 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
594 fs_info
->closing
= 1;
595 btrfs_transaction_flush_work(root
);
596 mutex_lock(&fs_info
->fs_mutex
);
597 trans
= btrfs_start_transaction(root
, 1);
598 btrfs_commit_transaction(trans
, root
);
599 /* run commit again to drop the original snapshot */
600 trans
= btrfs_start_transaction(root
, 1);
601 btrfs_commit_transaction(trans
, root
);
602 ret
= btrfs_write_and_wait_transaction(NULL
, root
);
604 write_ctree_super(NULL
, root
);
605 mutex_unlock(&fs_info
->fs_mutex
);
607 if (fs_info
->extent_root
->node
)
608 btrfs_block_release(fs_info
->extent_root
,
609 fs_info
->extent_root
->node
);
610 if (fs_info
->tree_root
->node
)
611 btrfs_block_release(fs_info
->tree_root
,
612 fs_info
->tree_root
->node
);
613 btrfs_block_release(root
, fs_info
->sb_buffer
);
614 crypto_free_hash(fs_info
->hash_tfm
);
615 truncate_inode_pages(fs_info
->btree_inode
->i_mapping
, 0);
616 iput(fs_info
->btree_inode
);
618 btrfs_free_block_groups(root
->fs_info
);
619 del_fs_roots(fs_info
);
620 kfree(fs_info
->extent_root
);
621 kfree(fs_info
->tree_root
);
625 void btrfs_block_release(struct btrfs_root
*root
, struct buffer_head
*buf
)
630 void btrfs_btree_balance_dirty(struct btrfs_root
*root
)
632 balance_dirty_pages_ratelimited(root
->fs_info
->btree_inode
->i_mapping
);