xref: /openbmc/linux/fs/btrfs/disk-io.h (revision 2f164822)
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 struct btrfs_tree_parent_check;
31 
32 void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info);
33 void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
34 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
35 			   struct btrfs_key *first_key, u64 parent_transid);
36 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
37 				      struct btrfs_tree_parent_check *check);
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_clear_buffer_dirty(struct btrfs_trans_handle *trans,
43 			      struct extent_buffer *buf);
44 void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info);
45 int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info);
46 int btrfs_check_super_csum(struct btrfs_fs_info *fs_info,
47 			   const struct btrfs_super_block *disk_sb);
48 int __cold open_ctree(struct super_block *sb,
49 	       struct btrfs_fs_devices *fs_devices,
50 	       char *options);
51 void __cold close_ctree(struct btrfs_fs_info *fs_info);
52 int btrfs_validate_super(struct btrfs_fs_info *fs_info,
53 			 struct btrfs_super_block *sb, int mirror_num);
54 int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount);
55 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
56 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
57 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
58 						   int copy_num, bool drop_cache);
59 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
60 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
61 					struct btrfs_key *key);
62 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
63 			 struct btrfs_root *root);
64 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
65 
66 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
67 				     u64 objectid, bool check_ref);
68 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
69 					 u64 objectid, dev_t anon_dev);
70 struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
71 						 struct btrfs_path *path,
72 						 u64 objectid);
73 int btrfs_global_root_insert(struct btrfs_root *root);
74 void btrfs_global_root_delete(struct btrfs_root *root);
75 struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info,
76 				     struct btrfs_key *key);
77 struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr);
78 struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr);
79 struct btrfs_root *btrfs_block_group_root(struct btrfs_fs_info *fs_info);
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 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
91 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info);
92 #endif
93 
94 /*
95  * This function is used to grab the root, and avoid it is freed when we
96  * access it. But it doesn't ensure that the tree is not dropped.
97  *
98  * If you want to ensure the whole tree is safe, you should use
99  * 	fs_info->subvol_srcu
100  */
101 static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root)
102 {
103 	if (!root)
104 		return NULL;
105 	if (refcount_inc_not_zero(&root->refs))
106 		return root;
107 	return NULL;
108 }
109 
110 void btrfs_put_root(struct btrfs_root *root);
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_extent_buffer(struct extent_buffer *buf,
115 			     struct btrfs_tree_parent_check *check);
116 
117 blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio);
118 int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans,
119 			      struct btrfs_root *root);
120 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
121 			     struct btrfs_fs_info *fs_info);
122 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
123 		       struct btrfs_root *root);
124 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
125 			     struct btrfs_fs_info *fs_info);
126 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
127 				  struct btrfs_fs_info *fs_info);
128 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
129 				     u64 objectid);
130 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
131 int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid);
132 int btrfs_init_root_free_objectid(struct btrfs_root *root);
133 
134 #endif
135