917634f2bae9b451e71634766c907fae72e4bc65
[sfrench/cifs-2.6.git] / fs / btrfs / disk-io.h
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         BTRFS_WQ_ENDIO_DIO_REPAIR,
29 };
30
31 static inline u64 btrfs_sb_offset(int mirror)
32 {
33         u64 start = SZ_16K;
34         if (mirror)
35                 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
36         return BTRFS_SUPER_INFO_OFFSET;
37 }
38
39 struct btrfs_device;
40 struct btrfs_fs_devices;
41
42 int btrfs_verify_level_key(struct btrfs_fs_info *fs_info,
43                            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 parent_transid, int level,
47                                       struct btrfs_key *first_key);
48 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr);
49 int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr,
50                          int mirror_num, struct extent_buffer **eb);
51 struct extent_buffer *btrfs_find_create_tree_block(
52                                                 struct btrfs_fs_info *fs_info,
53                                                 u64 bytenr);
54 void btrfs_clean_tree_block(struct extent_buffer *buf);
55 int open_ctree(struct super_block *sb,
56                struct btrfs_fs_devices *fs_devices,
57                char *options);
58 void close_ctree(struct btrfs_fs_info *fs_info);
59 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
60 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev);
61 int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
62                         struct buffer_head **bh_ret);
63 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
64 struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
65                                       struct btrfs_key *location);
66 int btrfs_init_fs_root(struct btrfs_root *root);
67 struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
68                                         u64 root_id);
69 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
70                          struct btrfs_root *root);
71 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
72
73 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
74                                      struct btrfs_key *key,
75                                      bool check_ref);
76 static inline struct btrfs_root *
77 btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
78                            struct btrfs_key *location)
79 {
80         return btrfs_get_fs_root(fs_info, location, true);
81 }
82
83 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
84 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
85 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
86 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
87                                  struct btrfs_root *root);
88 void btrfs_free_fs_root(struct btrfs_root *root);
89
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_fs_root(struct btrfs_root *root)
102 {
103         if (refcount_inc_not_zero(&root->refs))
104                 return root;
105         return NULL;
106 }
107
108 static inline void btrfs_put_fs_root(struct btrfs_root *root)
109 {
110         if (refcount_dec_and_test(&root->refs))
111                 kfree(root);
112 }
113
114 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
115 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
116                           int atomic);
117 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
118                       struct btrfs_key *first_key);
119 u32 btrfs_csum_data(const char *data, u32 seed, size_t len);
120 void btrfs_csum_final(u32 crc, u8 *result);
121 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
122                         enum btrfs_wq_endio_type metadata);
123 blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
124                         int mirror_num, unsigned long bio_flags,
125                         u64 bio_offset, void *private_data,
126                         extent_submit_bio_start_t *submit_bio_start);
127 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
128                           int mirror_num);
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                                      struct btrfs_fs_info *fs_info,
139                                      u64 objectid);
140 int btree_lock_page_hook(struct page *page, void *data,
141                                 void (*flush_fn)(void *));
142 struct extent_map *btree_get_extent(struct btrfs_inode *inode,
143                 struct page *page, size_t pg_offset, u64 start, u64 len,
144                 int create);
145 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
146 int __init btrfs_end_io_wq_init(void);
147 void __cold btrfs_end_io_wq_exit(void);
148
149 #ifdef CONFIG_DEBUG_LOCK_ALLOC
150 void btrfs_init_lockdep(void);
151 void btrfs_set_buffer_lockdep_class(u64 objectid,
152                                     struct extent_buffer *eb, int level);
153 #else
154 static inline void btrfs_init_lockdep(void)
155 { }
156 static inline void btrfs_set_buffer_lockdep_class(u64 objectid,
157                                         struct extent_buffer *eb, int level)
158 {
159 }
160 #endif
161
162 #endif