tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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
23enum btrfs_wq_endio_type {
24 BTRFS_WQ_ENDIO_DATA = 0,
25 BTRFS_WQ_ENDIO_METADATA = 1,
26 BTRFS_WQ_ENDIO_FREE_SPACE = 2,
27 BTRFS_WQ_ENDIO_RAID56 = 3,
28 BTRFS_WQ_ENDIO_DIO_REPAIR = 4,
29};
30
31static 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
39struct btrfs_device;
40struct btrfs_fs_devices;
41
42struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
43 u64 parent_transid, int level,
44 struct btrfs_key *first_key);
45void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr);
46int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr,
47 int mirror_num, struct extent_buffer **eb);
48struct extent_buffer *btrfs_find_create_tree_block(
49 struct btrfs_fs_info *fs_info,
50 u64 bytenr);
51void clean_tree_block(struct btrfs_fs_info *fs_info, struct extent_buffer *buf);
52int open_ctree(struct super_block *sb,
53 struct btrfs_fs_devices *fs_devices,
54 char *options);
55void close_ctree(struct btrfs_fs_info *fs_info);
56int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
57struct buffer_head *btrfs_read_dev_super(struct block_device *bdev);
58int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num,
59 struct buffer_head **bh_ret);
60int btrfs_commit_super(struct btrfs_fs_info *fs_info);
61struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root,
62 struct btrfs_key *location);
63int btrfs_init_fs_root(struct btrfs_root *root);
64struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
65 u64 root_id);
66int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
67 struct btrfs_root *root);
68void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
69
70struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
71 struct btrfs_key *key,
72 bool check_ref);
73static inline struct btrfs_root *
74btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
75 struct btrfs_key *location)
76{
77 return btrfs_get_fs_root(fs_info, location, true);
78}
79
80int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
81void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
82void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
83void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
84 struct btrfs_root *root);
85void btrfs_free_fs_root(struct btrfs_root *root);
86
87#ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
88struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info);
89#endif
90
91/*
92 * This function is used to grab the root, and avoid it is freed when we
93 * access it. But it doesn't ensure that the tree is not dropped.
94 *
95 * If you want to ensure the whole tree is safe, you should use
96 * fs_info->subvol_srcu
97 */
98static inline struct btrfs_root *btrfs_grab_fs_root(struct btrfs_root *root)
99{
100 if (refcount_inc_not_zero(&root->refs))
101 return root;
102 return NULL;
103}
104
105static inline void btrfs_put_fs_root(struct btrfs_root *root)
106{
107 if (refcount_dec_and_test(&root->refs))
108 kfree(root);
109}
110
111void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
112int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
113 int atomic);
114int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
115 struct btrfs_key *first_key);
116u32 btrfs_csum_data(const char *data, u32 seed, size_t len);
117void btrfs_csum_final(u32 crc, u8 *result);
118blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
119 enum btrfs_wq_endio_type metadata);
120blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
121 int mirror_num, unsigned long bio_flags,
122 u64 bio_offset, void *private_data,
123 extent_submit_bio_start_t *submit_bio_start,
124 extent_submit_bio_done_t *submit_bio_done);
125int btrfs_write_tree_block(struct extent_buffer *buf);
126void btrfs_wait_tree_block_writeback(struct extent_buffer *buf);
127int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
128 struct btrfs_fs_info *fs_info);
129int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
130 struct btrfs_root *root);
131void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
132 struct btrfs_fs_info *fs_info);
133void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
134 struct btrfs_fs_info *fs_info);
135struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
136 struct btrfs_fs_info *fs_info,
137 u64 objectid);
138int btree_lock_page_hook(struct page *page, void *data,
139 void (*flush_fn)(void *));
140struct extent_map *btree_get_extent(struct btrfs_inode *inode,
141 struct page *page, size_t pg_offset, u64 start, u64 len,
142 int create);
143int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
144int __init btrfs_end_io_wq_init(void);
145void __cold btrfs_end_io_wq_exit(void);
146
147#ifdef CONFIG_DEBUG_LOCK_ALLOC
148void btrfs_init_lockdep(void);
149void btrfs_set_buffer_lockdep_class(u64 objectid,
150 struct extent_buffer *eb, int level);
151#else
152static inline void btrfs_init_lockdep(void)
153{ }
154static inline void btrfs_set_buffer_lockdep_class(u64 objectid,
155 struct extent_buffer *eb, int level)
156{
157}
158#endif
159
160#endif