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_MIRROR_MAX	 3
10 #define BTRFS_SUPER_MIRROR_SHIFT 12
11 
12 /*
13  * Fixed blocksize for all devices, applies to specific ways of reading
14  * metadata like superblock. Must meet the set_blocksize requirements.
15  *
16  * Do not change.
17  */
18 #define BTRFS_BDEV_BLOCKSIZE	(4096)
19 
btrfs_sb_offset(int mirror)20 static inline u64 btrfs_sb_offset(int mirror)
21 {
22 	u64 start = SZ_16K;
23 	if (mirror)
24 		return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
25 	return BTRFS_SUPER_INFO_OFFSET;
26 }
27 
28 struct btrfs_device;
29 struct btrfs_fs_devices;
30 
31 void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info);
32 void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
33 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
34 			   struct btrfs_key *first_key, u64 parent_transid);
35 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
36 				      u64 owner_root, u64 parent_transid,
37 				      int level, struct btrfs_key *first_key);
38 struct extent_buffer *btrfs_find_create_tree_block(
39 						struct btrfs_fs_info *fs_info,
40 						u64 bytenr, u64 owner_root,
41 						int level);
42 void btrfs_clean_tree_block(struct extent_buffer *buf);
43 void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info);
44 int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info);
45 int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
46 			   const struct btrfs_super_block *disk_sb);
47 int __cold open_ctree(struct super_block *sb,
48 	       struct btrfs_fs_devices *fs_devices,
49 	       char *options);
50 void __cold close_ctree(struct btrfs_fs_info *fs_info);
51 int btrfs_validate_super(struct btrfs_fs_info *fs_info,
52 			 struct btrfs_super_block *sb, int mirror_num);
53 int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount);
54 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
55 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
56 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
57 						   int copy_num, bool drop_cache);
58 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
59 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
60 					struct btrfs_key *key);
61 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
62 			 struct btrfs_root *root);
63 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
64 
65 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
66 				     u64 objectid, bool check_ref);
67 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
68 					 u64 objectid, dev_t anon_dev);
69 struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
70 						 struct btrfs_path *path,
71 						 u64 objectid);
72 int btrfs_global_root_insert(struct btrfs_root *root);
73 void btrfs_global_root_delete(struct btrfs_root *root);
74 struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
75 				     struct btrfs_key *key);
76 struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr);
77 struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr);
78 
79 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
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 int btrfs_validate_metadata_buffer(struct btrfs_bio *bbio,
86 				   struct page *page, u64 start, u64 end,
87 				   int mirror);
88 void btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio, int mirror_num);
89 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
90 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info);
91 #endif
92 
93 /*
94  * This function is used to grab the root, and avoid it is freed when we
95  * access it. But it doesn't ensure that the tree is not dropped.
96  *
97  * If you want to ensure the whole tree is safe, you should use
98  * 	fs_info->subvol_srcu
99  */
btrfs_grab_root(struct btrfs_root * root)100 static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root)
101 {
102 	if (!root)
103 		return NULL;
104 	if (refcount_inc_not_zero(&root->refs))
105 		return root;
106 	return NULL;
107 }
108 
btrfs_block_group_root(struct btrfs_fs_info * fs_info)109 static inline struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info)
110 {
111 	if (btrfs_fs_compat_ro(fs_info, BLOCK_GROUP_TREE))
112 		return fs_info->block_group_root;
113 	return btrfs_extent_root(fs_info, 0);
114 }
115 
116 void btrfs_put_root(struct btrfs_root *root);
117 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
118 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
119 			  int atomic);
120 int btrfs_read_extent_buffer(struct extent_buffer *buf, u64 parent_transid,
121 			     int level, struct btrfs_key *first_key);
122 bool btrfs_wq_submit_bio(struct inode *inode, struct bio *bio, int mirror_num,
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 
145 #endif
146