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 #include <linux/sizes.h>
10 #include <linux/compiler_types.h>
11 #include "ctree.h"
12 #include "fs.h"
13
14 struct block_device;
15 struct super_block;
16 struct extent_buffer;
17 struct btrfs_device;
18 struct btrfs_fs_devices;
19 struct btrfs_fs_info;
20 struct btrfs_super_block;
21 struct btrfs_trans_handle;
22 struct btrfs_tree_parent_check;
23 struct btrfs_transaction;
24
25 #define BTRFS_SUPER_MIRROR_MAX 3
26 #define BTRFS_SUPER_MIRROR_SHIFT 12
27
28 /*
29 * Fixed blocksize for all devices, applies to specific ways of reading
30 * metadata like superblock. Must meet the set_blocksize requirements.
31 *
32 * Do not change.
33 */
34 #define BTRFS_BDEV_BLOCKSIZE (4096)
35
btrfs_sb_offset(int mirror)36 static inline u64 btrfs_sb_offset(int mirror)
37 {
38 u64 start = SZ_16K;
39 if (mirror)
40 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
41 return BTRFS_SUPER_INFO_OFFSET;
42 }
43
44 void btrfs_check_leaked_roots(const struct btrfs_fs_info *fs_info);
45 void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
46 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
47 struct btrfs_tree_parent_check *check);
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 int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info);
53 int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
54 const struct btrfs_super_block *disk_sb);
55 int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices,
56 const char *options);
57 void __cold close_ctree(struct btrfs_fs_info *fs_info);
58 int btrfs_validate_super(const struct btrfs_fs_info *fs_info,
59 const struct btrfs_super_block *sb, int mirror_num);
60 int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount);
61 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
62 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
63 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
64 int copy_num, bool drop_cache);
65 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
66 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
67 const struct btrfs_key *key);
68 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
69 struct btrfs_root *root);
70 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
71
72 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
73 u64 objectid, bool check_ref);
74 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
75 u64 objectid, dev_t *anon_dev);
76 struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
77 struct btrfs_path *path,
78 u64 objectid);
79 int btrfs_global_root_insert(struct btrfs_root *root);
80 void btrfs_global_root_delete(struct btrfs_root *root);
81 struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
82 struct btrfs_key *key);
83 struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr);
84 struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr);
85
86 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
87 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
88 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
89 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
90 struct btrfs_root *root);
91 int btrfs_validate_extent_buffer(struct extent_buffer *eb,
92 const struct btrfs_tree_parent_check *check);
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 btrfs_trans_handle *trans,
115 struct extent_buffer *buf);
116 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
117 int atomic);
118 int btrfs_read_extent_buffer(struct extent_buffer *buf,
119 const struct btrfs_tree_parent_check *check);
120
121 blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio);
122 int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
123 struct btrfs_root *root);
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 btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
135 int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid);
136 int btrfs_init_root_free_objectid(struct btrfs_root *root);
137
138 #endif
139