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.
20 #include <linux/blkdev.h>
21 #include <linux/crc32c.h>
22 #include <linux/scatterlist.h>
23 #include <linux/swap.h>
24 #include <linux/radix-tree.h>
25 #include <linux/writeback.h>
28 #include "transaction.h"
29 #include "btrfs_inode.h"
31 u64 bh_blocknr(struct buffer_head *bh)
36 static int check_tree_block(struct btrfs_root *root, struct buffer_head *buf)
38 struct btrfs_node *node = btrfs_buffer_node(buf);
39 if (bh_blocknr(buf) != btrfs_header_blocknr(&node->header)) {
40 printk(KERN_CRIT "bh_blocknr(buf) is %llu, header is %llu\n",
41 (unsigned long long)bh_blocknr(buf),
42 (unsigned long long)btrfs_header_blocknr(&node->header));
48 struct buffer_head *btrfs_find_tree_block(struct btrfs_root *root, u64 blocknr)
50 struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
51 int blockbits = root->fs_info->sb->s_blocksize_bits;
52 unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
54 struct buffer_head *bh;
55 struct buffer_head *head;
56 struct buffer_head *ret = NULL;
59 page = find_lock_page(mapping, index);
63 if (!page_has_buffers(page))
66 head = page_buffers(page);
69 if (buffer_mapped(bh) && bh_blocknr(bh) == blocknr) {
78 page_cache_release(page);
82 int btrfs_map_bh_to_logical(struct btrfs_root *root, struct buffer_head *bh,
88 set_buffer_mapped(bh);
90 map_bh(bh, root->fs_info->sb, logical);
95 struct buffer_head *btrfs_find_create_tree_block(struct btrfs_root *root,
98 struct address_space *mapping = root->fs_info->btree_inode->i_mapping;
99 int blockbits = root->fs_info->sb->s_blocksize_bits;
100 unsigned long index = blocknr >> (PAGE_CACHE_SHIFT - blockbits);
102 struct buffer_head *bh;
103 struct buffer_head *head;
104 struct buffer_head *ret = NULL;
106 u64 first_block = index << (PAGE_CACHE_SHIFT - blockbits);
108 page = find_or_create_page(mapping, index, GFP_NOFS);
112 if (!page_has_buffers(page))
113 create_empty_buffers(page, root->fs_info->sb->s_blocksize, 0);
114 head = page_buffers(page);
117 if (!buffer_mapped(bh)) {
118 err = btrfs_map_bh_to_logical(root, bh, first_block);
121 if (bh_blocknr(bh) == blocknr) {
126 bh = bh->b_this_page;
128 } while (bh != head);
133 page_cache_release(page);
137 static int btree_get_block(struct inode *inode, sector_t iblock,
138 struct buffer_head *bh, int create)
141 struct btrfs_root *root = BTRFS_I(bh->b_page->mapping->host)->root;
142 err = btrfs_map_bh_to_logical(root, bh, iblock);
146 int btrfs_csum_data(struct btrfs_root * root, char *data, size_t len,
150 crc = crc32c(0, data, len);
151 memcpy(result, &crc, BTRFS_CRC32_SIZE);
155 static int csum_tree_block(struct btrfs_root *root, struct buffer_head *bh,
158 char result[BTRFS_CRC32_SIZE];
160 struct btrfs_node *node;
162 ret = btrfs_csum_data(root, bh->b_data + BTRFS_CSUM_SIZE,
163 bh->b_size - BTRFS_CSUM_SIZE, result);
167 if (memcmp(bh->b_data, result, BTRFS_CRC32_SIZE)) {
168 printk("btrfs: %s checksum verify failed on %llu\n",
169 root->fs_info->sb->s_id,
170 (unsigned long long)bh_blocknr(bh));
174 node = btrfs_buffer_node(bh);
175 memcpy(node->header.csum, result, BTRFS_CRC32_SIZE);
180 static int btree_writepage(struct page *page, struct writeback_control *wbc)
182 struct buffer_head *bh;
183 struct btrfs_root *root = BTRFS_I(page->mapping->host)->root;
184 struct buffer_head *head;
185 if (!page_has_buffers(page)) {
186 create_empty_buffers(page, root->fs_info->sb->s_blocksize,
187 (1 << BH_Dirty)|(1 << BH_Uptodate));
189 head = page_buffers(page);
192 if (buffer_dirty(bh))
193 csum_tree_block(root, bh, 0);
194 bh = bh->b_this_page;
195 } while (bh != head);
196 return block_write_full_page(page, btree_get_block, wbc);
199 static int btree_readpage(struct file * file, struct page * page)
201 return block_read_full_page(page, btree_get_block);
204 static struct address_space_operations btree_aops = {
205 .readpage = btree_readpage,
206 .writepage = btree_writepage,
207 .sync_page = block_sync_page,
210 int readahead_tree_block(struct btrfs_root *root, u64 blocknr)
212 struct buffer_head *bh = NULL;
215 bh = btrfs_find_create_tree_block(root, blocknr);
218 if (buffer_uptodate(bh)) {
222 if (test_set_buffer_locked(bh)) {
226 if (!buffer_uptodate(bh)) {
228 bh->b_end_io = end_buffer_read_sync;
239 struct buffer_head *read_tree_block(struct btrfs_root *root, u64 blocknr)
241 struct buffer_head *bh = NULL;
243 bh = btrfs_find_create_tree_block(root, blocknr);
246 if (buffer_uptodate(bh))
249 if (!buffer_uptodate(bh)) {
251 bh->b_end_io = end_buffer_read_sync;
254 if (!buffer_uptodate(bh))
260 if (!buffer_checked(bh)) {
261 csum_tree_block(root, bh, 1);
262 set_buffer_checked(bh);
264 if (check_tree_block(root, bh))
272 int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
273 struct buffer_head *buf)
275 WARN_ON(atomic_read(&buf->b_count) == 0);
277 clear_buffer_dirty(buf);
282 static int __setup_root(int blocksize,
283 struct btrfs_root *root,
284 struct btrfs_fs_info *fs_info,
289 root->commit_root = NULL;
290 root->blocksize = blocksize;
292 root->fs_info = fs_info;
293 root->objectid = objectid;
294 root->last_trans = 0;
295 root->highest_inode = 0;
296 root->last_inode_alloc = 0;
298 memset(&root->root_key, 0, sizeof(root->root_key));
299 memset(&root->root_item, 0, sizeof(root->root_item));
300 memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
301 memset(&root->root_kobj, 0, sizeof(root->root_kobj));
302 init_completion(&root->kobj_unregister);
303 init_rwsem(&root->snap_sem);
304 root->defrag_running = 0;
305 root->defrag_level = 0;
306 root->root_key.objectid = objectid;
310 static int find_and_setup_root(int blocksize,
311 struct btrfs_root *tree_root,
312 struct btrfs_fs_info *fs_info,
314 struct btrfs_root *root)
318 __setup_root(blocksize, root, fs_info, objectid);
319 ret = btrfs_find_last_root(tree_root, objectid,
320 &root->root_item, &root->root_key);
323 root->node = read_tree_block(root,
324 btrfs_root_blocknr(&root->root_item));
329 struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_fs_info *fs_info,
330 struct btrfs_key *location)
332 struct btrfs_root *root;
333 struct btrfs_root *tree_root = fs_info->tree_root;
334 struct btrfs_path *path;
335 struct btrfs_leaf *l;
339 root = kzalloc(sizeof(*root), GFP_NOFS);
341 return ERR_PTR(-ENOMEM);
342 if (location->offset == (u64)-1) {
343 ret = find_and_setup_root(fs_info->sb->s_blocksize,
344 fs_info->tree_root, fs_info,
345 location->objectid, root);
353 __setup_root(fs_info->sb->s_blocksize, root, fs_info,
356 path = btrfs_alloc_path();
358 ret = btrfs_search_slot(NULL, tree_root, location, path, 0, 0);
364 l = btrfs_buffer_leaf(path->nodes[0]);
365 memcpy(&root->root_item,
366 btrfs_item_ptr(l, path->slots[0], struct btrfs_root_item),
367 sizeof(root->root_item));
368 memcpy(&root->root_key, location, sizeof(*location));
371 btrfs_release_path(root, path);
372 btrfs_free_path(path);
377 root->node = read_tree_block(root,
378 btrfs_root_blocknr(&root->root_item));
382 ret = btrfs_find_highest_inode(root, &highest_inode);
384 root->highest_inode = highest_inode;
385 root->last_inode_alloc = highest_inode;
390 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
391 struct btrfs_key *location,
392 const char *name, int namelen)
394 struct btrfs_root *root;
397 root = radix_tree_lookup(&fs_info->fs_roots_radix,
398 (unsigned long)location->objectid);
402 root = btrfs_read_fs_root_no_radix(fs_info, location);
405 ret = radix_tree_insert(&fs_info->fs_roots_radix,
406 (unsigned long)root->root_key.objectid,
414 ret = btrfs_set_root_name(root, name, namelen);
421 ret = btrfs_sysfs_add_root(root);
429 ret = btrfs_find_dead_roots(fs_info->tree_root,
430 root->root_key.objectid, root);
436 struct btrfs_root *open_ctree(struct super_block *sb)
438 struct btrfs_root *extent_root = kmalloc(sizeof(struct btrfs_root),
440 struct btrfs_root *tree_root = kmalloc(sizeof(struct btrfs_root),
442 struct btrfs_fs_info *fs_info = kmalloc(sizeof(*fs_info),
446 struct btrfs_super_block *disk_super;
448 if (!extent_root || !tree_root || !fs_info) {
452 init_bit_radix(&fs_info->pinned_radix);
453 init_bit_radix(&fs_info->pending_del_radix);
454 init_bit_radix(&fs_info->extent_map_radix);
455 init_bit_radix(&fs_info->extent_ins_radix);
456 INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_NOFS);
457 INIT_RADIX_TREE(&fs_info->block_group_radix, GFP_KERNEL);
458 INIT_RADIX_TREE(&fs_info->block_group_data_radix, GFP_KERNEL);
459 INIT_LIST_HEAD(&fs_info->trans_list);
460 INIT_LIST_HEAD(&fs_info->dead_roots);
461 memset(&fs_info->super_kobj, 0, sizeof(fs_info->super_kobj));
462 init_completion(&fs_info->kobj_unregister);
463 sb_set_blocksize(sb, 4096);
464 fs_info->running_transaction = NULL;
465 fs_info->last_trans_committed = 0;
466 fs_info->tree_root = tree_root;
467 fs_info->extent_root = extent_root;
469 fs_info->btree_inode = new_inode(sb);
470 fs_info->btree_inode->i_ino = 1;
471 fs_info->btree_inode->i_nlink = 1;
472 fs_info->btree_inode->i_size = sb->s_bdev->bd_inode->i_size;
473 fs_info->btree_inode->i_mapping->a_ops = &btree_aops;
474 fs_info->do_barriers = 1;
475 fs_info->closing = 0;
477 INIT_DELAYED_WORK(&fs_info->trans_work, btrfs_transaction_cleaner);
478 BTRFS_I(fs_info->btree_inode)->root = tree_root;
479 memset(&BTRFS_I(fs_info->btree_inode)->location, 0,
480 sizeof(struct btrfs_key));
481 insert_inode_hash(fs_info->btree_inode);
482 mapping_set_gfp_mask(fs_info->btree_inode->i_mapping, GFP_NOFS);
484 mutex_init(&fs_info->trans_mutex);
485 mutex_init(&fs_info->fs_mutex);
487 __setup_root(sb->s_blocksize, tree_root,
488 fs_info, BTRFS_ROOT_TREE_OBJECTID);
490 fs_info->sb_buffer = read_tree_block(tree_root,
491 BTRFS_SUPER_INFO_OFFSET /
494 if (!fs_info->sb_buffer)
496 disk_super = (struct btrfs_super_block *)fs_info->sb_buffer->b_data;
497 fs_info->disk_super = disk_super;
498 memcpy(&fs_info->super_copy, disk_super, sizeof(fs_info->super_copy));
500 if (!btrfs_super_root(disk_super))
503 i_size_write(fs_info->btree_inode,
504 btrfs_super_total_blocks(disk_super) <<
505 fs_info->btree_inode->i_blkbits);
508 if (strncmp((char *)(&disk_super->magic), BTRFS_MAGIC,
509 sizeof(disk_super->magic))) {
510 printk("btrfs: valid FS not found on %s\n", sb->s_id);
513 tree_root->node = read_tree_block(tree_root,
514 btrfs_super_root(disk_super));
515 if (!tree_root->node)
518 mutex_lock(&fs_info->fs_mutex);
519 ret = find_and_setup_root(sb->s_blocksize, tree_root, fs_info,
520 BTRFS_EXTENT_TREE_OBJECTID, extent_root);
522 mutex_unlock(&fs_info->fs_mutex);
526 btrfs_read_block_groups(extent_root);
528 fs_info->generation = btrfs_super_generation(disk_super) + 1;
529 mutex_unlock(&fs_info->fs_mutex);
533 btrfs_block_release(tree_root, tree_root->node);
535 btrfs_block_release(tree_root, fs_info->sb_buffer);
537 iput(fs_info->btree_inode);
545 int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root
549 struct buffer_head *bh = root->fs_info->sb_buffer;
552 WARN_ON(atomic_read(&bh->b_count) < 1);
553 clear_buffer_dirty(bh);
554 csum_tree_block(root, bh, 0);
555 bh->b_end_io = end_buffer_write_sync;
557 if (root->fs_info->do_barriers)
558 ret = submit_bh(WRITE_BARRIER, bh);
560 ret = submit_bh(WRITE, bh);
561 if (ret == -EOPNOTSUPP) {
564 set_buffer_uptodate(bh);
565 root->fs_info->do_barriers = 0;
566 ret = submit_bh(WRITE, bh);
569 if (!buffer_uptodate(bh)) {
576 int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root)
578 radix_tree_delete(&fs_info->fs_roots_radix,
579 (unsigned long)root->root_key.objectid);
580 btrfs_sysfs_del_root(root);
585 if (root->commit_root)
586 brelse(root->commit_root);
593 static int del_fs_roots(struct btrfs_fs_info *fs_info)
596 struct btrfs_root *gang[8];
600 ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
605 for (i = 0; i < ret; i++)
606 btrfs_free_fs_root(fs_info, gang[i]);
611 int close_ctree(struct btrfs_root *root)
614 struct btrfs_trans_handle *trans;
615 struct btrfs_fs_info *fs_info = root->fs_info;
617 fs_info->closing = 1;
618 btrfs_transaction_flush_work(root);
619 mutex_lock(&fs_info->fs_mutex);
620 btrfs_defrag_dirty_roots(root->fs_info);
621 trans = btrfs_start_transaction(root, 1);
622 ret = btrfs_commit_transaction(trans, root);
623 /* run commit again to drop the original snapshot */
624 trans = btrfs_start_transaction(root, 1);
625 btrfs_commit_transaction(trans, root);
626 ret = btrfs_write_and_wait_transaction(NULL, root);
628 write_ctree_super(NULL, root);
629 mutex_unlock(&fs_info->fs_mutex);
631 if (fs_info->extent_root->node)
632 btrfs_block_release(fs_info->extent_root,
633 fs_info->extent_root->node);
634 if (fs_info->tree_root->node)
635 btrfs_block_release(fs_info->tree_root,
636 fs_info->tree_root->node);
637 btrfs_block_release(root, fs_info->sb_buffer);
638 truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
639 iput(fs_info->btree_inode);
641 btrfs_free_block_groups(root->fs_info);
642 del_fs_roots(fs_info);
643 kfree(fs_info->extent_root);
644 kfree(fs_info->tree_root);
648 void btrfs_mark_buffer_dirty(struct buffer_head *bh)
650 struct btrfs_root *root = BTRFS_I(bh->b_page->mapping->host)->root;
651 u64 transid = btrfs_header_generation(btrfs_buffer_header(bh));
653 WARN_ON(!atomic_read(&bh->b_count));
655 if (transid != root->fs_info->generation) {
656 printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n",
657 (unsigned long long)bh->b_blocknr,
658 transid, root->fs_info->generation);
661 mark_buffer_dirty(bh);
664 void btrfs_block_release(struct btrfs_root *root, struct buffer_head *buf)
669 void btrfs_btree_balance_dirty(struct btrfs_root *root)
671 balance_dirty_pages_ratelimited(root->fs_info->btree_inode->i_mapping);