1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2007 Oracle. All rights reserved.
4 */
5
6 #ifndef BTRFS_DISK_IO_H
7 #define BTRFS_DISK_IO_H
8
9 #define BTRFS_SUPER_INFO_OFFSET SZ_64K
10 #define BTRFS_SUPER_INFO_SIZE 4096
11
12 #define BTRFS_SUPER_MIRROR_MAX 3
13 #define BTRFS_SUPER_MIRROR_SHIFT 12
14
15 /*
16 * Fixed blocksize for all devices, applies to specific ways of reading
17 * metadata like superblock. Must meet the set_blocksize requirements.
18 *
19 * Do not change.
20 */
21 #define BTRFS_BDEV_BLOCKSIZE (4096)
22
23 enum btrfs_wq_endio_type {
24 BTRFS_WQ_ENDIO_DATA,
25 BTRFS_WQ_ENDIO_METADATA,
26 BTRFS_WQ_ENDIO_FREE_SPACE,
27 BTRFS_WQ_ENDIO_RAID56,
28 };
29
btrfs_sb_offset(int mirror)30 static inline u64 btrfs_sb_offset(int mirror)
31 {
32 u64 start = SZ_16K;
33 if (mirror)
34 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
35 return BTRFS_SUPER_INFO_OFFSET;
36 }
37
38 struct btrfs_device;
39 struct btrfs_fs_devices;
40
41 void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info);
42 void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
43 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
44 struct btrfs_key *first_key, u64 parent_transid);
45 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
46 u64 owner_root, u64 parent_transid,
47 int level, struct btrfs_key *first_key);
48 struct extent_buffer *btrfs_find_create_tree_block(
49 struct btrfs_fs_info *fs_info,
50 u64 bytenr, u64 owner_root,
51 int level);
52 void btrfs_clean_tree_block(struct extent_buffer *buf);
53 void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info);
54 int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info);
55 int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
56 const struct btrfs_super_block *disk_sb);
57 int __cold open_ctree(struct super_block *sb,
58 struct btrfs_fs_devices *fs_devices,
59 char *options);
60 void __cold close_ctree(struct btrfs_fs_info *fs_info);
61 int btrfs_validate_super(struct btrfs_fs_info *fs_info,
62 struct btrfs_super_block *sb, int mirror_num);
63 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
64 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
65 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
66 int copy_num, bool drop_cache);
67 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
68 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
69 struct btrfs_key *key);
70 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
71 struct btrfs_root *root);
72 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
73
74 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
75 u64 objectid, bool check_ref);
76 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
77 u64 objectid, dev_t anon_dev);
78 struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
79 struct btrfs_path *path,
80 u64 objectid);
81
82 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
83 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
84 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
85 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
86 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
87 struct btrfs_root *root);
88 int btrfs_validate_metadata_buffer(struct btrfs_io_bio *io_bio,
89 struct page *page, u64 start, u64 end,
90 int mirror);
91 blk_status_t btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio,
92 int mirror_num, unsigned long bio_flags);
93 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
94 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info);
95 #endif
96
97 /*
98 * This function is used to grab the root, and avoid it is freed when we
99 * access it. But it doesn't ensure that the tree is not dropped.
100 *
101 * If you want to ensure the whole tree is safe, you should use
102 * fs_info->subvol_srcu
103 */
btrfs_grab_root(struct btrfs_root * root)104 static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root)
105 {
106 if (!root)
107 return NULL;
108 if (refcount_inc_not_zero(&root->refs))
109 return root;
110 return NULL;
111 }
112
113 void btrfs_put_root(struct btrfs_root *root);
114 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
115 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
116 int atomic);
117 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
118 struct btrfs_key *first_key);
119 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
120 enum btrfs_wq_endio_type metadata);
121 blk_status_t btrfs_wq_submit_bio(struct inode *inode, struct bio *bio,
122 int mirror_num, unsigned long bio_flags,
123 u64 dio_file_offset,
124 extent_submit_bio_start_t *submit_bio_start);
125 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
126 int mirror_num);
127 int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
128 struct btrfs_root *root);
129 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
130 struct btrfs_fs_info *fs_info);
131 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
132 struct btrfs_root *root);
133 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
134 struct btrfs_fs_info *fs_info);
135 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
136 struct btrfs_fs_info *fs_info);
137 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
138 u64 objectid);
139 int btree_lock_page_hook(struct page *page, void *data,
140 void (*flush_fn)(void *));
141 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
142 int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid);
143 int btrfs_init_root_free_objectid(struct btrfs_root *root);
144 int __init btrfs_end_io_wq_init(void);
145 void __cold btrfs_end_io_wq_exit(void);
146
147 #endif
148