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"
18 struct block_device
*bdev
;
21 int btrfs_insert_dev_radix(struct btrfs_root
*root
,
22 struct block_device
*bdev
,
27 struct dev_lookup
*lookup
;
30 lookup
= kmalloc(sizeof(*lookup
), GFP_NOFS
);
33 lookup
->block_start
= block_start
;
34 lookup
->num_blocks
= num_blocks
;
36 lookup
->device_id
= device_id
;
38 ret
= radix_tree_insert(&root
->fs_info
->dev_radix
, block_start
+
39 num_blocks
- 1, lookup
);
43 u64
bh_blocknr(struct buffer_head
*bh
)
45 int blkbits
= bh
->b_page
->mapping
->host
->i_blkbits
;
46 u64 blocknr
= bh
->b_page
->index
<< (PAGE_CACHE_SHIFT
- blkbits
);
49 if (PageHighMem(bh
->b_page
))
50 offset
= (unsigned long)bh
->b_data
;
52 offset
= bh
->b_data
- (char *)page_address(bh
->b_page
);
53 blocknr
+= offset
>> (PAGE_CACHE_SHIFT
- blkbits
);
57 static int check_tree_block(struct btrfs_root
*root
, struct buffer_head
*buf
)
59 struct btrfs_node
*node
= btrfs_buffer_node(buf
);
60 if (bh_blocknr(buf
) != btrfs_header_blocknr(&node
->header
)) {
61 printk(KERN_CRIT
"bh_blocknr(buf) is %Lu, header is %Lu\n",
62 bh_blocknr(buf
), btrfs_header_blocknr(&node
->header
));
68 struct buffer_head
*btrfs_find_tree_block(struct btrfs_root
*root
, u64 blocknr
)
70 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
71 int blockbits
= root
->fs_info
->sb
->s_blocksize_bits
;
72 unsigned long index
= blocknr
>> (PAGE_CACHE_SHIFT
- blockbits
);
74 struct buffer_head
*bh
;
75 struct buffer_head
*head
;
76 struct buffer_head
*ret
= NULL
;
79 page
= find_lock_page(mapping
, index
);
83 if (!page_has_buffers(page
))
86 head
= page_buffers(page
);
89 if (buffer_mapped(bh
) && bh_blocknr(bh
) == blocknr
) {
98 page_cache_release(page
);
102 int btrfs_map_bh_to_logical(struct btrfs_root
*root
, struct buffer_head
*bh
,
105 struct dev_lookup
*lookup
[2];
112 set_buffer_mapped(bh
);
115 root
= root
->fs_info
->dev_root
;
116 ret
= radix_tree_gang_lookup(&root
->fs_info
->dev_radix
,
118 (unsigned long)logical
,
120 if (ret
== 0 || lookup
[0]->block_start
> logical
||
121 lookup
[0]->block_start
+ lookup
[0]->num_blocks
<= logical
) {
125 bh
->b_bdev
= lookup
[0]->bdev
;
126 bh
->b_blocknr
= logical
- lookup
[0]->block_start
;
127 set_buffer_mapped(bh
);
133 struct buffer_head
*btrfs_find_create_tree_block(struct btrfs_root
*root
,
136 struct address_space
*mapping
= root
->fs_info
->btree_inode
->i_mapping
;
137 int blockbits
= root
->fs_info
->sb
->s_blocksize_bits
;
138 unsigned long index
= blocknr
>> (PAGE_CACHE_SHIFT
- blockbits
);
140 struct buffer_head
*bh
;
141 struct buffer_head
*head
;
142 struct buffer_head
*ret
= NULL
;
144 u64 first_block
= index
<< (PAGE_CACHE_SHIFT
- blockbits
);
146 page
= grab_cache_page(mapping
, index
);
150 if (!page_has_buffers(page
))
151 create_empty_buffers(page
, root
->fs_info
->sb
->s_blocksize
, 0);
152 head
= page_buffers(page
);
155 if (!buffer_mapped(bh
)) {
156 err
= btrfs_map_bh_to_logical(root
, bh
, first_block
);
159 if (bh_blocknr(bh
) == blocknr
) {
164 bh
= bh
->b_this_page
;
166 } while (bh
!= head
);
171 page_cache_release(page
);
175 static int btree_get_block(struct inode
*inode
, sector_t iblock
,
176 struct buffer_head
*bh
, int create
)
179 struct btrfs_root
*root
= BTRFS_I(bh
->b_page
->mapping
->host
)->root
;
180 err
= btrfs_map_bh_to_logical(root
, bh
, iblock
);
184 int btrfs_csum_data(struct btrfs_root
* root
, char *data
, size_t len
,
187 struct scatterlist sg
;
188 struct crypto_hash
*tfm
= root
->fs_info
->hash_tfm
;
189 struct hash_desc desc
;
194 sg_init_one(&sg
, data
, len
);
195 spin_lock(&root
->fs_info
->hash_lock
);
196 ret
= crypto_hash_digest(&desc
, &sg
, 1, result
);
197 spin_unlock(&root
->fs_info
->hash_lock
);
199 printk("digest failed\n");
203 static int csum_tree_block(struct btrfs_root
*root
, struct buffer_head
*bh
,
206 char result
[BTRFS_CRC32_SIZE
];
208 struct btrfs_node
*node
;
210 ret
= btrfs_csum_data(root
, bh
->b_data
+ BTRFS_CSUM_SIZE
,
211 bh
->b_size
- BTRFS_CSUM_SIZE
, result
);
215 if (memcmp(bh
->b_data
, result
, BTRFS_CRC32_SIZE
)) {
216 printk("checksum verify failed on %Lu\n",
221 node
= btrfs_buffer_node(bh
);
222 memcpy(node
->header
.csum
, result
, BTRFS_CRC32_SIZE
);
227 static int btree_writepage(struct page
*page
, struct writeback_control
*wbc
)
229 struct buffer_head
*bh
;
230 struct btrfs_root
*root
= BTRFS_I(page
->mapping
->host
)->root
;
231 struct buffer_head
*head
;
232 if (!page_has_buffers(page
)) {
233 create_empty_buffers(page
, root
->fs_info
->sb
->s_blocksize
,
234 (1 << BH_Dirty
)|(1 << BH_Uptodate
));
236 head
= page_buffers(page
);
239 if (buffer_dirty(bh
))
240 csum_tree_block(root
, bh
, 0);
241 bh
= bh
->b_this_page
;
242 } while (bh
!= head
);
243 return block_write_full_page(page
, btree_get_block
, wbc
);
246 static int btree_readpage(struct file
* file
, struct page
* page
)
248 return block_read_full_page(page
, btree_get_block
);
251 static struct address_space_operations btree_aops
= {
252 .readpage
= btree_readpage
,
253 .writepage
= btree_writepage
,
254 .sync_page
= block_sync_page
,
257 int readahead_tree_block(struct btrfs_root
*root
, u64 blocknr
)
259 struct buffer_head
*bh
= NULL
;
262 bh
= btrfs_find_create_tree_block(root
, blocknr
);
265 if (buffer_uptodate(bh
)) {
269 if (test_set_buffer_locked(bh
)) {
273 if (!buffer_uptodate(bh
)) {
275 bh
->b_end_io
= end_buffer_read_sync
;
286 struct buffer_head
*read_tree_block(struct btrfs_root
*root
, u64 blocknr
)
288 struct buffer_head
*bh
= NULL
;
290 bh
= btrfs_find_create_tree_block(root
, blocknr
);
293 if (buffer_uptodate(bh
))
296 if (!buffer_uptodate(bh
)) {
298 bh
->b_end_io
= end_buffer_read_sync
;
301 if (!buffer_uptodate(bh
))
307 if (!buffer_checked(bh
)) {
308 csum_tree_block(root
, bh
, 1);
309 set_buffer_checked(bh
);
311 if (check_tree_block(root
, bh
))
319 int dirty_tree_block(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
320 struct buffer_head
*buf
)
322 WARN_ON(atomic_read(&buf
->b_count
) == 0);
323 mark_buffer_dirty(buf
);
327 int clean_tree_block(struct btrfs_trans_handle
*trans
, struct btrfs_root
*root
,
328 struct buffer_head
*buf
)
330 WARN_ON(atomic_read(&buf
->b_count
) == 0);
331 clear_buffer_dirty(buf
);
335 static int __setup_root(int blocksize
,
336 struct btrfs_root
*root
,
337 struct btrfs_fs_info
*fs_info
,
342 root
->commit_root
= NULL
;
343 root
->blocksize
= blocksize
;
345 root
->fs_info
= fs_info
;
346 root
->objectid
= objectid
;
347 root
->last_trans
= 0;
348 root
->highest_inode
= 0;
349 root
->last_inode_alloc
= 0;
350 memset(&root
->root_key
, 0, sizeof(root
->root_key
));
351 memset(&root
->root_item
, 0, sizeof(root
->root_item
));
352 root
->root_key
.objectid
= objectid
;
356 static int find_and_setup_root(int blocksize
,
357 struct btrfs_root
*tree_root
,
358 struct btrfs_fs_info
*fs_info
,
360 struct btrfs_root
*root
)
364 __setup_root(blocksize
, root
, fs_info
, objectid
);
365 ret
= btrfs_find_last_root(tree_root
, objectid
,
366 &root
->root_item
, &root
->root_key
);
369 root
->node
= read_tree_block(root
,
370 btrfs_root_blocknr(&root
->root_item
));
375 struct btrfs_root
*btrfs_read_fs_root(struct btrfs_fs_info
*fs_info
,
376 struct btrfs_key
*location
)
378 struct btrfs_root
*root
;
379 struct btrfs_root
*tree_root
= fs_info
->tree_root
;
380 struct btrfs_path
*path
;
381 struct btrfs_leaf
*l
;
385 printk("read_fs_root looking for %Lu %Lu %u\n", location
->objectid
, location
->offset
, location
->flags
);
386 root
= radix_tree_lookup(&fs_info
->fs_roots_radix
,
387 (unsigned long)location
->objectid
);
389 printk("found %p in cache\n", root
);
392 root
= kmalloc(sizeof(*root
), GFP_NOFS
);
395 return ERR_PTR(-ENOMEM
);
397 if (location
->offset
== (u64
)-1) {
398 ret
= find_and_setup_root(fs_info
->sb
->s_blocksize
,
399 fs_info
->tree_root
, fs_info
,
400 location
->objectid
, root
);
409 __setup_root(fs_info
->sb
->s_blocksize
, root
, fs_info
,
412 path
= btrfs_alloc_path();
414 ret
= btrfs_search_slot(NULL
, tree_root
, location
, path
, 0, 0);
416 printk("internal search_slot gives us %d\n", ret
);
421 l
= btrfs_buffer_leaf(path
->nodes
[0]);
422 memcpy(&root
->root_item
,
423 btrfs_item_ptr(l
, path
->slots
[0], struct btrfs_root_item
),
424 sizeof(root
->root_item
));
425 memcpy(&root
->root_key
, location
, sizeof(*location
));
428 btrfs_release_path(root
, path
);
429 btrfs_free_path(path
);
434 root
->node
= read_tree_block(root
,
435 btrfs_root_blocknr(&root
->root_item
));
438 printk("inserting %p\n", root
);
440 ret
= radix_tree_insert(&fs_info
->fs_roots_radix
,
441 (unsigned long)root
->root_key
.objectid
,
444 printk("radix_tree_insert gives us %d\n", ret
);
449 ret
= btrfs_find_highest_inode(root
, &highest_inode
);
451 root
->highest_inode
= highest_inode
;
452 root
->last_inode_alloc
= highest_inode
;
453 printk("highest inode is %Lu\n", highest_inode
);
455 printk("all worked\n");
459 static int btrfs_open_disk(struct btrfs_root
*root
, u64 device_id
,
460 u64 block_start
, u64 num_blocks
,
461 char *filename
, int name_len
)
464 struct block_device
*bdev
;
467 null_filename
= kmalloc(name_len
+ 1, GFP_NOFS
);
470 memcpy(null_filename
, filename
, name_len
);
471 null_filename
[name_len
] = '\0';
473 bdev
= open_bdev_excl(null_filename
, O_RDWR
, root
->fs_info
->sb
);
478 set_blocksize(bdev
, root
->fs_info
->sb
->s_blocksize
);
479 ret
= btrfs_insert_dev_radix(root
, bdev
, device_id
,
480 block_start
, num_blocks
);
484 kfree(null_filename
);
488 static int read_device_info(struct btrfs_root
*root
)
490 struct btrfs_path
*path
;
492 struct btrfs_key key
;
493 struct btrfs_leaf
*leaf
;
494 struct btrfs_device_item
*dev_item
;
498 root
= root
->fs_info
->dev_root
;
500 path
= btrfs_alloc_path();
506 btrfs_set_key_type(&key
, BTRFS_DEV_ITEM_KEY
);
508 mutex_lock(&root
->fs_info
->fs_mutex
);
509 ret
= btrfs_search_slot(NULL
, root
, &key
, path
, 0, 0);
510 leaf
= btrfs_buffer_leaf(path
->nodes
[0]);
511 nritems
= btrfs_header_nritems(&leaf
->header
);
513 slot
= path
->slots
[0];
514 if (slot
>= nritems
) {
515 ret
= btrfs_next_leaf(root
, path
);
518 leaf
= btrfs_buffer_leaf(path
->nodes
[0]);
519 nritems
= btrfs_header_nritems(&leaf
->header
);
520 slot
= path
->slots
[0];
522 btrfs_disk_key_to_cpu(&key
, &leaf
->items
[slot
].key
);
523 if (btrfs_key_type(&key
) != BTRFS_DEV_ITEM_KEY
) {
527 dev_item
= btrfs_item_ptr(leaf
, slot
, struct btrfs_device_item
);
528 printk("found key %Lu %Lu\n", key
.objectid
, key
.offset
);
529 if (btrfs_device_id(dev_item
) !=
530 btrfs_super_device_id(root
->fs_info
->disk_super
)) {
531 ret
= btrfs_open_disk(root
, btrfs_device_id(dev_item
),
532 key
.objectid
, key
.offset
,
533 (char *)(dev_item
+ 1),
534 btrfs_device_pathlen(dev_item
));
539 btrfs_free_path(path
);
540 mutex_unlock(&root
->fs_info
->fs_mutex
);
544 struct btrfs_root
*open_ctree(struct super_block
*sb
)
546 struct btrfs_root
*extent_root
= kmalloc(sizeof(struct btrfs_root
),
548 struct btrfs_root
*dev_root
= kmalloc(sizeof(struct btrfs_root
),
550 struct btrfs_root
*tree_root
= kmalloc(sizeof(struct btrfs_root
),
552 struct btrfs_fs_info
*fs_info
= kmalloc(sizeof(*fs_info
),
555 struct btrfs_super_block
*disk_super
;
556 struct dev_lookup
*dev_lookup
;
558 init_bit_radix(&fs_info
->pinned_radix
);
559 init_bit_radix(&fs_info
->pending_del_radix
);
560 init_bit_radix(&fs_info
->extent_map_radix
);
561 INIT_RADIX_TREE(&fs_info
->fs_roots_radix
, GFP_NOFS
);
562 INIT_RADIX_TREE(&fs_info
->dev_radix
, GFP_NOFS
);
563 INIT_RADIX_TREE(&fs_info
->block_group_radix
, GFP_KERNEL
);
564 INIT_RADIX_TREE(&fs_info
->block_group_data_radix
, GFP_KERNEL
);
565 INIT_LIST_HEAD(&fs_info
->trans_list
);
566 sb_set_blocksize(sb
, 4096);
567 fs_info
->running_transaction
= NULL
;
568 fs_info
->tree_root
= tree_root
;
569 fs_info
->extent_root
= extent_root
;
570 fs_info
->dev_root
= dev_root
;
572 fs_info
->btree_inode
= new_inode(sb
);
573 fs_info
->btree_inode
->i_ino
= 1;
574 fs_info
->btree_inode
->i_nlink
= 1;
575 fs_info
->btree_inode
->i_size
= sb
->s_bdev
->bd_inode
->i_size
;
576 fs_info
->btree_inode
->i_mapping
->a_ops
= &btree_aops
;
577 fs_info
->do_barriers
= 1;
578 fs_info
->extent_tree_insert_nr
= 0;
579 fs_info
->extent_tree_prealloc_nr
= 0;
580 BTRFS_I(fs_info
->btree_inode
)->root
= tree_root
;
581 memset(&BTRFS_I(fs_info
->btree_inode
)->location
, 0,
582 sizeof(struct btrfs_key
));
583 insert_inode_hash(fs_info
->btree_inode
);
584 mapping_set_gfp_mask(fs_info
->btree_inode
->i_mapping
, GFP_NOFS
);
585 fs_info
->hash_tfm
= crypto_alloc_hash("crc32c", 0, CRYPTO_ALG_ASYNC
);
586 spin_lock_init(&fs_info
->hash_lock
);
587 if (!fs_info
->hash_tfm
|| IS_ERR(fs_info
->hash_tfm
)) {
588 printk("failed to allocate digest hash\n");
591 mutex_init(&fs_info
->trans_mutex
);
592 mutex_init(&fs_info
->fs_mutex
);
594 __setup_root(sb
->s_blocksize
, dev_root
,
595 fs_info
, BTRFS_DEV_TREE_OBJECTID
);
597 __setup_root(sb
->s_blocksize
, tree_root
,
598 fs_info
, BTRFS_ROOT_TREE_OBJECTID
);
600 dev_lookup
= kmalloc(sizeof(*dev_lookup
), GFP_NOFS
);
601 dev_lookup
->block_start
= 0;
602 dev_lookup
->num_blocks
= (u32
)-2;
603 dev_lookup
->bdev
= sb
->s_bdev
;
604 dev_lookup
->device_id
= 0;
605 ret
= radix_tree_insert(&fs_info
->dev_radix
, (u32
)-2, dev_lookup
);
607 fs_info
->sb_buffer
= read_tree_block(tree_root
,
608 BTRFS_SUPER_INFO_OFFSET
/
611 if (!fs_info
->sb_buffer
)
613 disk_super
= (struct btrfs_super_block
*)fs_info
->sb_buffer
->b_data
;
614 if (!btrfs_super_root(disk_super
))
617 i_size_write(fs_info
->btree_inode
,
618 btrfs_super_total_blocks(disk_super
) <<
619 fs_info
->btree_inode
->i_blkbits
);
621 radix_tree_delete(&fs_info
->dev_radix
, (u32
)-2);
622 dev_lookup
->block_start
= btrfs_super_device_block_start(disk_super
);
623 dev_lookup
->num_blocks
= btrfs_super_device_num_blocks(disk_super
);
624 dev_lookup
->device_id
= btrfs_super_device_id(disk_super
);
626 ret
= radix_tree_insert(&fs_info
->dev_radix
,
627 dev_lookup
->block_start
+
628 dev_lookup
->num_blocks
- 1, dev_lookup
);
631 fs_info
->disk_super
= disk_super
;
633 dev_root
->node
= read_tree_block(tree_root
,
634 btrfs_super_device_root(disk_super
));
636 ret
= read_device_info(dev_root
);
639 tree_root
->node
= read_tree_block(tree_root
,
640 btrfs_super_root(disk_super
));
641 BUG_ON(!tree_root
->node
);
643 mutex_lock(&fs_info
->fs_mutex
);
644 ret
= find_and_setup_root(sb
->s_blocksize
, tree_root
, fs_info
,
645 BTRFS_EXTENT_TREE_OBJECTID
, extent_root
);
648 btrfs_read_block_groups(extent_root
);
650 fs_info
->generation
= btrfs_super_generation(disk_super
) + 1;
651 memset(&fs_info
->kobj
, 0, sizeof(fs_info
->kobj
));
652 kobj_set_kset_s(fs_info
, btrfs_subsys
);
653 kobject_set_name(&fs_info
->kobj
, "%s", sb
->s_id
);
654 kobject_register(&fs_info
->kobj
);
655 mutex_unlock(&fs_info
->fs_mutex
);
659 int write_ctree_super(struct btrfs_trans_handle
*trans
, struct btrfs_root
663 struct buffer_head
*bh
= root
->fs_info
->sb_buffer
;
665 btrfs_set_super_root(root
->fs_info
->disk_super
,
666 bh_blocknr(root
->fs_info
->tree_root
->node
));
668 WARN_ON(atomic_read(&bh
->b_count
) < 1);
669 clear_buffer_dirty(bh
);
670 csum_tree_block(root
, bh
, 0);
671 bh
->b_end_io
= end_buffer_write_sync
;
673 if (root
->fs_info
->do_barriers
)
674 ret
= submit_bh(WRITE_BARRIER
, bh
);
676 ret
= submit_bh(WRITE
, bh
);
677 if (ret
== -EOPNOTSUPP
) {
678 set_buffer_uptodate(bh
);
679 root
->fs_info
->do_barriers
= 0;
680 ret
= submit_bh(WRITE
, bh
);
683 if (!buffer_uptodate(bh
)) {
690 static int free_fs_root(struct btrfs_fs_info
*fs_info
, struct btrfs_root
*root
)
692 radix_tree_delete(&fs_info
->fs_roots_radix
,
693 (unsigned long)root
->root_key
.objectid
);
698 if (root
->commit_root
)
699 brelse(root
->commit_root
);
704 static int del_fs_roots(struct btrfs_fs_info
*fs_info
)
707 struct btrfs_root
*gang
[8];
711 ret
= radix_tree_gang_lookup(&fs_info
->fs_roots_radix
,
716 for (i
= 0; i
< ret
; i
++)
717 free_fs_root(fs_info
, gang
[i
]);
722 static int free_dev_radix(struct btrfs_fs_info
*fs_info
)
724 struct dev_lookup
*lookup
[8];
725 struct block_device
*super_bdev
= fs_info
->sb
->s_bdev
;
729 ret
= radix_tree_gang_lookup(&fs_info
->dev_radix
,
734 for (i
= 0; i
< ret
; i
++) {
735 if (lookup
[i
]->bdev
!= super_bdev
)
736 close_bdev_excl(lookup
[i
]->bdev
);
737 radix_tree_delete(&fs_info
->dev_radix
,
738 lookup
[i
]->block_start
+
739 lookup
[i
]->num_blocks
- 1);
746 int close_ctree(struct btrfs_root
*root
)
749 struct btrfs_trans_handle
*trans
;
750 struct btrfs_fs_info
*fs_info
= root
->fs_info
;
752 mutex_lock(&fs_info
->fs_mutex
);
753 trans
= btrfs_start_transaction(root
, 1);
754 btrfs_commit_transaction(trans
, root
);
755 /* run commit again to drop the original snapshot */
756 trans
= btrfs_start_transaction(root
, 1);
757 btrfs_commit_transaction(trans
, root
);
758 ret
= btrfs_write_and_wait_transaction(NULL
, root
);
760 write_ctree_super(NULL
, root
);
761 mutex_unlock(&fs_info
->fs_mutex
);
763 if (fs_info
->extent_root
->node
)
764 btrfs_block_release(fs_info
->extent_root
,
765 fs_info
->extent_root
->node
);
766 if (fs_info
->dev_root
->node
)
767 btrfs_block_release(fs_info
->dev_root
,
768 fs_info
->dev_root
->node
);
769 if (fs_info
->tree_root
->node
)
770 btrfs_block_release(fs_info
->tree_root
,
771 fs_info
->tree_root
->node
);
772 btrfs_block_release(root
, fs_info
->sb_buffer
);
773 crypto_free_hash(fs_info
->hash_tfm
);
774 truncate_inode_pages(fs_info
->btree_inode
->i_mapping
, 0);
775 iput(fs_info
->btree_inode
);
777 free_dev_radix(fs_info
);
778 btrfs_free_block_groups(root
->fs_info
);
779 del_fs_roots(fs_info
);
780 kfree(fs_info
->extent_root
);
781 kfree(fs_info
->tree_root
);
782 kobject_unregister(&fs_info
->kobj
);
786 void btrfs_block_release(struct btrfs_root
*root
, struct buffer_head
*buf
)
791 void btrfs_btree_balance_dirty(struct btrfs_root
*root
)
793 balance_dirty_pages_ratelimited(root
->fs_info
->btree_inode
->i_mapping
);