xref: /kernel/linux/linux-5.10/fs/btrfs/disk-io.h (revision 8c2ecf20)
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,
25	BTRFS_WQ_ENDIO_METADATA,
26	BTRFS_WQ_ENDIO_FREE_SPACE,
27	BTRFS_WQ_ENDIO_RAID56,
28};
29
30static 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
38struct btrfs_device;
39struct btrfs_fs_devices;
40
41void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info);
42void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
43int btrfs_verify_level_key(struct extent_buffer *eb, int level,
44			   struct btrfs_key *first_key, u64 parent_transid);
45struct 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);
48void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr);
49struct extent_buffer *btrfs_find_create_tree_block(
50						struct btrfs_fs_info *fs_info,
51						u64 bytenr);
52void btrfs_clean_tree_block(struct extent_buffer *buf);
53int __cold open_ctree(struct super_block *sb,
54	       struct btrfs_fs_devices *fs_devices,
55	       char *options);
56void __cold close_ctree(struct btrfs_fs_info *fs_info);
57int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
58struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
59struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
60						   int copy_num);
61int btrfs_commit_super(struct btrfs_fs_info *fs_info);
62struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
63					struct btrfs_key *key);
64int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
65			 struct btrfs_root *root);
66void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
67
68struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
69				     u64 objectid, bool check_ref);
70struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
71					 u64 objectid, dev_t anon_dev);
72struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info,
73						 struct btrfs_path *path,
74						 u64 objectid);
75
76void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
77int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
78void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
79void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
80void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
81				 struct btrfs_root *root);
82int btrfs_validate_metadata_buffer(struct btrfs_io_bio *io_bio, u64 phy_offset,
83				   struct page *page, u64 start, u64 end,
84				   int mirror);
85blk_status_t btrfs_submit_metadata_bio(struct inode *inode, struct bio *bio,
86				       int mirror_num, unsigned long bio_flags);
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_root(struct btrfs_root *root)
99{
100	if (!root)
101		return NULL;
102	if (refcount_inc_not_zero(&root->refs))
103		return root;
104	return NULL;
105}
106
107void btrfs_put_root(struct btrfs_root *root);
108void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
109int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
110			  int atomic);
111int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
112		      struct btrfs_key *first_key);
113blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
114			enum btrfs_wq_endio_type metadata);
115blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
116			int mirror_num, unsigned long bio_flags,
117			u64 bio_offset, void *private_data,
118			extent_submit_bio_start_t *submit_bio_start);
119blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
120			  int mirror_num);
121int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
122			     struct btrfs_fs_info *fs_info);
123int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
124		       struct btrfs_root *root);
125void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
126			     struct btrfs_fs_info *fs_info);
127void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
128				  struct btrfs_fs_info *fs_info);
129struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
130				     u64 objectid);
131int btree_lock_page_hook(struct page *page, void *data,
132				void (*flush_fn)(void *));
133int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
134int btrfs_find_free_objectid(struct btrfs_root *root, u64 *objectid);
135int btrfs_find_highest_objectid(struct btrfs_root *root, u64 *objectid);
136int __init btrfs_end_io_wq_init(void);
137void __cold btrfs_end_io_wq_exit(void);
138
139#ifdef CONFIG_DEBUG_LOCK_ALLOC
140void btrfs_init_lockdep(void);
141void btrfs_set_buffer_lockdep_class(u64 objectid,
142			            struct extent_buffer *eb, int level);
143#else
144static inline void btrfs_init_lockdep(void)
145{ }
146static inline void btrfs_set_buffer_lockdep_class(u64 objectid,
147					struct extent_buffer *eb, int level)
148{
149}
150#endif
151
152#endif
153