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 
20 enum btrfs_wq_endio_type {
21 	BTRFS_WQ_ENDIO_DATA,
22 	BTRFS_WQ_ENDIO_METADATA,
23 	BTRFS_WQ_ENDIO_FREE_SPACE,
24 	BTRFS_WQ_ENDIO_RAID56,
25 };
26 
btrfs_sb_offset(int mirror)27 static inline u64 btrfs_sb_offset(int mirror)
28 {
29 	u64 start = SZ_16K;
30 	if (mirror)
31 		return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
32 	return BTRFS_SUPER_INFO_OFFSET;
33 }
34 
35 struct btrfs_device;
36 struct btrfs_fs_devices;
37 
38 void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info);
39 void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
40 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
41 			   struct btrfs_key *first_key, u64 parent_transid);
42 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
43 				      u64 owner_root, u64 parent_transid,
44 				      int level, struct btrfs_key *first_key);
45 struct extent_buffer *btrfs_find_create_tree_block(
46 						struct btrfs_fs_info *fs_info,
47 						u64 bytenr, u64 owner_root,
48 						int level);
49 void btrfs_clean_tree_block(struct extent_buffer *buf);
50 void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info);
51 int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info);
52 int __cold open_ctree(struct super_block *sb,
53 	       struct btrfs_fs_devices *fs_devices,
54 	       char *options);
55 void __cold close_ctree(struct btrfs_fs_info *fs_info);
56 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
57 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
58 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
59 						   int copy_num);
60 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
61 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
62 					struct btrfs_key *key);
63 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
64 			 struct btrfs_root *root);
65 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
66 
67 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
68 				     u64 objectid, bool check_ref);
69 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
70 					 u64 objectid, dev_t anon_dev);
71 struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
72 						 struct btrfs_path *path,
73 						 u64 objectid);
74 int btrfs_global_root_insert(struct btrfs_root *root);
75 void btrfs_global_root_delete(struct btrfs_root *root);
76 struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
77 				     struct btrfs_key *key);
78 struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr);
79 struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr);
80 
81 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
82 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
83 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
84 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
85 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
86 				 struct btrfs_root *root);
87 int btrfs_validate_metadata_buffer(struct btrfs_bio *bbio,
88 				   struct page *page, u64 start, u64 end,
89 				   int mirror);
90 void btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio, int mirror_num);
91 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
92 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info);
93 #endif
94 
95 /*
96  * This function is used to grab the root, and avoid it is freed when we
97  * access it. But it doesn't ensure that the tree is not dropped.
98  *
99  * If you want to ensure the whole tree is safe, you should use
100  * 	fs_info->subvol_srcu
101  */
btrfs_grab_root(struct btrfs_root * root)102 static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root)
103 {
104 	if (!root)
105 		return NULL;
106 	if (refcount_inc_not_zero(&root->refs))
107 		return root;
108 	return NULL;
109 }
110 
btrfs_block_group_root(struct btrfs_fs_info * fs_info)111 static inline struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info)
112 {
113 	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
114 		return fs_info->block_group_root;
115 	return btrfs_extent_root(fs_info, 0);
116 }
117 
118 void btrfs_put_root(struct btrfs_root *root);
119 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
120 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
121 			  int atomic);
122 int btrfs_read_extent_buffer(struct extent_buffer *buf, u64 parent_transid,
123 			     int level, struct btrfs_key *first_key);
124 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
125 			enum btrfs_wq_endio_type metadata);
126 blk_status_t btrfs_wq_submit_bio(struct inode *inode, struct bio *bio,
127 				 int mirror_num, u64 dio_file_offset,
128 				 extent_submit_bio_start_t *submit_bio_start);
129 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
130 			  int mirror_num);
131 int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
132 			      struct btrfs_root *root);
133 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
134 			     struct btrfs_fs_info *fs_info);
135 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
136 		       struct btrfs_root *root);
137 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
138 			     struct btrfs_fs_info *fs_info);
139 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
140 				  struct btrfs_fs_info *fs_info);
141 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
142 				     u64 objectid);
143 int btree_lock_page_hook(struct page *page, void *data,
144 				void (*flush_fn)(void *));
145 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
146 int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid);
147 int btrfs_init_root_free_objectid(struct btrfs_root *root);
148 int __init btrfs_end_io_wq_init(void);
149 void __cold btrfs_end_io_wq_exit(void);
150 
151 #endif
152