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 BTRFS_WQ_ENDIO_DIO_REPAIR,
29 };
30
btrfs_sb_offset(int mirror)31 static inline u64 btrfs_sb_offset(int mirror)
32 {
33 u64 start = SZ_16K;
34 if (mirror)
35 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
36 return BTRFS_SUPER_INFO_OFFSET;
37 }
38
39 struct btrfs_device;
40 struct btrfs_fs_devices;
41
42 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
43 struct btrfs_key *first_key, u64 parent_transid);
44 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
45 u64 parent_transid, int level,
46 struct btrfs_key *first_key);
47 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr);
48 struct extent_buffer *btrfs_find_create_tree_block(
49 struct btrfs_fs_info *fs_info,
50 u64 bytenr);
51 void btrfs_clean_tree_block(struct extent_buffer *buf);
52 int open_ctree(struct super_block *sb,
53 struct btrfs_fs_devices *fs_devices,
54 char *options);
55 void close_ctree(struct btrfs_fs_info *fs_info);
56 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
57 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev);
58 int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
59 struct buffer_head **bh_ret);
60 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
61 struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
62 struct btrfs_key *location);
63 int btrfs_init_fs_root(struct btrfs_root *root);
64 struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
65 u64 root_id);
66 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
67 struct btrfs_root *root);
68 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
69
70 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
71 struct btrfs_key *key,
72 bool check_ref);
73 static inline struct btrfs_root *
btrfs_read_fs_root_no_name(struct btrfs_fs_info * fs_info,struct btrfs_key * location)74 btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
75 struct btrfs_key *location)
76 {
77 return btrfs_get_fs_root(fs_info, location, true);
78 }
79
80 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
81 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
82 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
83 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
84 struct btrfs_root *root);
85 void btrfs_free_fs_root(struct btrfs_root *root);
86
87 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
88 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info);
89 #endif
90
91 /*
92 * This function is used to grab the root, and avoid it is freed when we
93 * access it. But it doesn't ensure that the tree is not dropped.
94 *
95 * If you want to ensure the whole tree is safe, you should use
96 * fs_info->subvol_srcu
97 */
btrfs_grab_fs_root(struct btrfs_root * root)98 static inline struct btrfs_root *btrfs_grab_fs_root(struct btrfs_root *root)
99 {
100 if (refcount_inc_not_zero(&root->refs))
101 return root;
102 return NULL;
103 }
104
btrfs_put_fs_root(struct btrfs_root * root)105 static inline void btrfs_put_fs_root(struct btrfs_root *root)
106 {
107 if (refcount_dec_and_test(&root->refs))
108 kfree(root);
109 }
110
111 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
112 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
113 int atomic);
114 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
115 struct btrfs_key *first_key);
116 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
117 enum btrfs_wq_endio_type metadata);
118 blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
119 int mirror_num, unsigned long bio_flags,
120 u64 bio_offset, void *private_data,
121 extent_submit_bio_start_t *submit_bio_start);
122 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
123 int mirror_num);
124 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
125 struct btrfs_fs_info *fs_info);
126 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
127 struct btrfs_root *root);
128 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
129 struct btrfs_fs_info *fs_info);
130 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
131 struct btrfs_fs_info *fs_info);
132 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
133 u64 objectid);
134 int btree_lock_page_hook(struct page *page, void *data,
135 void (*flush_fn)(void *));
136 struct extent_map *btree_get_extent(struct btrfs_inode *inode,
137 struct page *page, size_t pg_offset, u64 start, u64 len,
138 int create);
139 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
140 int __init btrfs_end_io_wq_init(void);
141 void __cold btrfs_end_io_wq_exit(void);
142
143 #ifdef CONFIG_DEBUG_LOCK_ALLOC
144 void btrfs_init_lockdep(void);
145 void btrfs_set_buffer_lockdep_class(u64 objectid,
146 struct extent_buffer *eb, int level);
147 #else
btrfs_init_lockdep(void)148 static inline void btrfs_init_lockdep(void)
149 { }
btrfs_set_buffer_lockdep_class(u64 objectid,struct extent_buffer * eb,int level)150 static inline void btrfs_set_buffer_lockdep_class(u64 objectid,
151 struct extent_buffer *eb, int level)
152 {
153 }
154 #endif
155
156 #endif
157
