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 = 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 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 struct 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); 45 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr); 46 int reada_tree_block_flagged(struct btrfs_fs_info *fs_info, u64 bytenr, 47 int mirror_num, struct extent_buffer **eb); 48 struct extent_buffer *btrfs_find_create_tree_block( 49 struct btrfs_fs_info *fs_info, 50 u64 bytenr); 51 void clean_tree_block(struct btrfs_fs_info *fs_info, struct extent_buffer *buf); 52 int open_ctree(struct super_block *sb, 53 struct btrfs_fs_devices *fs_devices, 54 char *options); 55 void close_ctree(struct btrfs_fs_info *fs_info); 56 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors); 57 struct buffer_head *btrfs_read_dev_super(struct block_device *bdev); 58 int btrfs_read_dev_one_super(struct block_device *bdev, int copy_num, 59 struct buffer_head **bh_ret); 60 int btrfs_commit_super(struct btrfs_fs_info *fs_info); 61 struct btrfs_root *btrfs_read_fs_root(struct btrfs_root *tree_root, 62 struct btrfs_key *location); 63 int btrfs_init_fs_root(struct btrfs_root *root); 64 struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info, 65 u64 root_id); 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 struct btrfs_key *key, 72 bool check_ref); 73 static inline struct btrfs_root * 74 btrfs_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 80 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info); 81 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info); 82 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info); 83 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info, 84 struct btrfs_root *root); 85 void btrfs_free_fs_root(struct btrfs_root *root); 86 87 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 88 struct 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 */ 98 static 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 } 104 105 static inline void btrfs_put_fs_root(struct btrfs_root *root) 106 { 107 if (refcount_dec_and_test(&root->refs)) 108 kfree(root); 109 } 110 111 void btrfs_mark_buffer_dirty(struct extent_buffer *buf); 112 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, 113 int atomic); 114 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level, 115 struct btrfs_key *first_key); 116 u32 btrfs_csum_data(const char *data, u32 seed, size_t len); 117 void btrfs_csum_final(u32 crc, u8 *result); 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 extent_submit_bio_done_t *submit_bio_done); 125 int btrfs_write_tree_block(struct extent_buffer *buf); 126 void btrfs_wait_tree_block_writeback(struct extent_buffer *buf); 127 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, 128 struct btrfs_fs_info *fs_info); 129 int btrfs_add_log_tree(struct btrfs_trans_handle *trans, 130 struct btrfs_root *root); 131 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans, 132 struct btrfs_fs_info *fs_info); 133 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans, 134 struct btrfs_fs_info *fs_info); 135 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, 136 struct btrfs_fs_info *fs_info, 137 u64 objectid); 138 int btree_lock_page_hook(struct page *page, void *data, 139 void (*flush_fn)(void *)); 140 struct extent_map *btree_get_extent(struct btrfs_inode *inode, 141 struct page *page, size_t pg_offset, u64 start, u64 len, 142 int create); 143 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags); 144 int __init btrfs_end_io_wq_init(void); 145 void __cold btrfs_end_io_wq_exit(void); 146 147 #ifdef CONFIG_DEBUG_LOCK_ALLOC 148 void btrfs_init_lockdep(void); 149 void btrfs_set_buffer_lockdep_class(u64 objectid, 150 struct extent_buffer *eb, int level); 151 #else 152 static inline void btrfs_init_lockdep(void) 153 { } 154 static inline void btrfs_set_buffer_lockdep_class(u64 objectid, 155 struct extent_buffer *eb, int level) 156 { 157 } 158 #endif 159 160 #endif 161