xref: /openbmc/linux/fs/btrfs/disk-io.h (revision bbb774d9)
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 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 __cold open_ctree(struct super_block *sb,
46 	       struct btrfs_fs_devices *fs_devices,
47 	       char *options);
48 void __cold close_ctree(struct btrfs_fs_info *fs_info);
49 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
50 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
51 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
52 						   int copy_num);
53 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
54 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
55 					struct btrfs_key *key);
56 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
57 			 struct btrfs_root *root);
58 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
59 
60 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
61 				     u64 objectid, bool check_ref);
62 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
63 					 u64 objectid, dev_t anon_dev);
64 struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
65 						 struct btrfs_path *path,
66 						 u64 objectid);
67 int btrfs_global_root_insert(struct btrfs_root *root);
68 void btrfs_global_root_delete(struct btrfs_root *root);
69 struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
70 				     struct btrfs_key *key);
71 struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr);
72 struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr);
73 
74 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
75 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
76 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
77 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
78 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
79 				 struct btrfs_root *root);
80 int btrfs_validate_metadata_buffer(struct btrfs_bio *bbio,
81 				   struct page *page, u64 start, u64 end,
82 				   int mirror);
83 void btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio, int mirror_num);
84 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
85 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info);
86 #endif
87 
88 /*
89  * This function is used to grab the root, and avoid it is freed when we
90  * access it. But it doesn't ensure that the tree is not dropped.
91  *
92  * If you want to ensure the whole tree is safe, you should use
93  * 	fs_info->subvol_srcu
94  */
95 static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root)
96 {
97 	if (!root)
98 		return NULL;
99 	if (refcount_inc_not_zero(&root->refs))
100 		return root;
101 	return NULL;
102 }
103 
104 static inline struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info)
105 {
106 	if (btrfs_fs_incompat(fs_info, EXTENT_TREE_V2))
107 		return fs_info->block_group_root;
108 	return btrfs_extent_root(fs_info, 0);
109 }
110 
111 void btrfs_put_root(struct btrfs_root *root);
112 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
113 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
114 			  int atomic);
115 int btrfs_read_extent_buffer(struct extent_buffer *buf, u64 parent_transid,
116 			     int level, struct btrfs_key *first_key);
117 bool btrfs_wq_submit_bio(struct inode *inode, struct bio *bio, int mirror_num,
118 			 u64 dio_file_offset,
119 			 extent_submit_bio_start_t *submit_bio_start);
120 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
121 			  int mirror_num);
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 btree_lock_page_hook(struct page *page, void *data,
135 				void (*flush_fn)(void *));
136 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
137 int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid);
138 int btrfs_init_root_free_objectid(struct btrfs_root *root);
139 
140 #endif
141