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 extent_buffer *eb, int level, 43 struct btrfs_key *first_key, u64 parent_transid); 44 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr, 45 u64 parent_transid, int level, 46 struct btrfs_key *first_key); 47 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr); 48 int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr, 49 int mirror_num, struct extent_buffer **eb); 50 struct extent_buffer *btrfs_find_create_tree_block( 51 struct btrfs_fs_info *fs_info, 52 u64 bytenr); 53 void btrfs_clean_tree_block(struct extent_buffer *buf); 54 int open_ctree(struct super_block *sb, 55 struct btrfs_fs_devices *fs_devices, 56 char *options); 57 void close_ctree(struct btrfs_fs_info *fs_info); 58 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors); 59 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev); 60 int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num, 61 struct buffer_head **bh_ret); 62 int btrfs_commit_super(struct btrfs_fs_info *fs_info); 63 struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root, 64 struct btrfs_key *location); 65 int btrfs_init_fs_root(struct btrfs_root *root); 66 struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info, 67 u64 root_id); 68 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info, 69 struct btrfs_root *root); 70 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info); 71 72 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, 73 struct btrfs_key *key, 74 bool check_ref); 75 static inline struct btrfs_root * 76 btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info, 77 struct btrfs_key *location) 78 { 79 return btrfs_get_fs_root(fs_info, location, true); 80 } 81 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 void btrfs_free_fs_root(struct btrfs_root *root); 88 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_fs_root(struct btrfs_root *root) 101 { 102 if (refcount_inc_not_zero(&root->refs)) 103 return root; 104 return NULL; 105 } 106 107 static inline void btrfs_put_fs_root(struct btrfs_root *root) 108 { 109 if (refcount_dec_and_test(&root->refs)) 110 kfree(root); 111 } 112 113 void btrfs_mark_buffer_dirty(struct extent_buffer *buf); 114 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, 115 int atomic); 116 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level, 117 struct btrfs_key *first_key); 118 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio, 119 enum btrfs_wq_endio_type metadata); 120 blk_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 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio, 125 int mirror_num); 126 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, 127 struct btrfs_fs_info *fs_info); 128 int btrfs_add_log_tree(struct btrfs_trans_handle *trans, 129 struct btrfs_root *root); 130 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans, 131 struct btrfs_fs_info *fs_info); 132 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans, 133 struct btrfs_fs_info *fs_info); 134 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, 135 u64 objectid); 136 int btree_lock_page_hook(struct page *page, void *data, 137 void (*flush_fn)(void *)); 138 struct extent_map *btree_get_extent(struct btrfs_inode *inode, 139 struct page *page, size_t pg_offset, u64 start, u64 len, 140 int create); 141 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags); 142 int __init btrfs_end_io_wq_init(void); 143 void __cold btrfs_end_io_wq_exit(void); 144 145 #ifdef CONFIG_DEBUG_LOCK_ALLOC 146 void btrfs_init_lockdep(void); 147 void btrfs_set_buffer_lockdep_class(u64 objectid, 148 struct extent_buffer *eb, int level); 149 #else 150 static inline void btrfs_init_lockdep(void) 151 { } 152 static inline void btrfs_set_buffer_lockdep_class(u64 objectid, 153 struct extent_buffer *eb, int level) 154 { 155 } 156 #endif 157 158 #endif 159