xref: /openbmc/linux/fs/btrfs/disk-io.h (revision 842ed298)
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_INFO_OFFSET SZ_64K
10 #define BTRFS_SUPER_INFO_SIZE 4096
11 
12 #define BTRFS_SUPER_MIRROR_MAX	 3
13 #define BTRFS_SUPER_MIRROR_SHIFT 12
14 
15 /*
16  * Fixed blocksize for all devices, applies to specific ways of reading
17  * metadata like superblock. Must meet the set_blocksize requirements.
18  *
19  * Do not change.
20  */
21 #define BTRFS_BDEV_BLOCKSIZE	(4096)
22 
23 enum btrfs_wq_endio_type {
24 	BTRFS_WQ_ENDIO_DATA,
25 	BTRFS_WQ_ENDIO_METADATA,
26 	BTRFS_WQ_ENDIO_FREE_SPACE,
27 	BTRFS_WQ_ENDIO_RAID56,
28 };
29 
30 static inline u64 btrfs_sb_offset(int mirror)
31 {
32 	u64 start = SZ_16K;
33 	if (mirror)
34 		return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
35 	return BTRFS_SUPER_INFO_OFFSET;
36 }
37 
38 struct btrfs_device;
39 struct btrfs_fs_devices;
40 
41 void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info);
42 void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
43 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
44 			   struct btrfs_key *first_key, u64 parent_transid);
45 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
46 				      u64 owner_root, u64 parent_transid,
47 				      int level, struct btrfs_key *first_key);
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 void btrfs_clean_tree_block(struct extent_buffer *buf);
53 void btrfs_clear_oneshot_options(struct btrfs_fs_info *fs_info);
54 int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info);
55 int __cold open_ctree(struct super_block *sb,
56 	       struct btrfs_fs_devices *fs_devices,
57 	       char *options);
58 void __cold close_ctree(struct btrfs_fs_info *fs_info);
59 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
60 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
61 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
62 						   int copy_num);
63 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
64 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
65 					struct btrfs_key *key);
66 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
67 			 struct btrfs_root *root);
68 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
69 
70 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
71 				     u64 objectid, bool check_ref);
72 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
73 					 u64 objectid, dev_t anon_dev);
74 struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
75 						 struct btrfs_path *path,
76 						 u64 objectid);
77 
78 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
79 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
80 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
81 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
82 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
83 				 struct btrfs_root *root);
84 int btrfs_validate_metadata_buffer(struct btrfs_io_bio *io_bio,
85 				   struct page *page, u64 start, u64 end,
86 				   int mirror);
87 blk_status_t btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio,
88 				       int mirror_num, unsigned long bio_flags);
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  */
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 
109 void btrfs_put_root(struct btrfs_root *root);
110 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
111 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
112 			  int atomic);
113 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
114 		      struct btrfs_key *first_key);
115 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
116 			enum btrfs_wq_endio_type metadata);
117 blk_status_t btrfs_wq_submit_bio(struct inode *inode, struct bio *bio,
118 				 int mirror_num, unsigned long bio_flags,
119 				 u64 dio_file_offset,
120 				 extent_submit_bio_start_t *submit_bio_start);
121 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
122 			  int mirror_num);
123 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
124 			     struct btrfs_fs_info *fs_info);
125 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
126 		       struct btrfs_root *root);
127 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
128 			     struct btrfs_fs_info *fs_info);
129 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
130 				  struct btrfs_fs_info *fs_info);
131 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
132 				     u64 objectid);
133 int btree_lock_page_hook(struct page *page, void *data,
134 				void (*flush_fn)(void *));
135 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
136 int btrfs_find_free_objectid(struct btrfs_root *root, u64 *objectid);
137 int btrfs_find_highest_objectid(struct btrfs_root *root, u64 *objectid);
138 int __init btrfs_end_io_wq_init(void);
139 void __cold btrfs_end_io_wq_exit(void);
140 
141 #ifdef CONFIG_DEBUG_LOCK_ALLOC
142 void btrfs_set_buffer_lockdep_class(u64 objectid,
143 			            struct extent_buffer *eb, int level);
144 #else
145 static inline void btrfs_set_buffer_lockdep_class(u64 objectid,
146 					struct extent_buffer *eb, int level)
147 {
148 }
149 #endif
150 
151 #endif
152