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 #include <linux/sizes.h> 10 #include <linux/compiler_types.h> 11 #include "ctree.h" 12 #include "fs.h" 13 14 struct block_device; 15 struct super_block; 16 struct extent_buffer; 17 struct btrfs_device; 18 struct btrfs_fs_devices; 19 struct btrfs_fs_info; 20 struct btrfs_super_block; 21 struct btrfs_trans_handle; 22 struct btrfs_tree_parent_check; 23 struct btrfs_transaction; 24 25 #define BTRFS_SUPER_MIRROR_MAX 3 26 #define BTRFS_SUPER_MIRROR_SHIFT 12 27 28 /* 29 * Fixed blocksize for all devices, applies to specific ways of reading 30 * metadata like superblock. Must meet the set_blocksize requirements. 31 * 32 * Do not change. 33 */ 34 #define BTRFS_BDEV_BLOCKSIZE (4096) 35 36 static inline u64 btrfs_sb_offset(int mirror) 37 { 38 u64 start = SZ_16K; 39 if (mirror) 40 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror); 41 return BTRFS_SUPER_INFO_OFFSET; 42 } 43 44 void btrfs_check_leaked_roots(const struct btrfs_fs_info *fs_info); 45 void btrfs_init_fs_info(struct btrfs_fs_info *fs_info); 46 struct extent_buffer *read_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr, 47 struct btrfs_tree_parent_check *check); 48 struct extent_buffer *btrfs_find_create_tree_block( 49 struct btrfs_fs_info *fs_info, 50 u64 bytenr, u64 owner_root, 51 int level); 52 int btrfs_start_pre_rw_mount(struct btrfs_fs_info *fs_info); 53 int btrfs_check_super_csum(struct btrfs_fs_info *fs_info, 54 const struct btrfs_super_block *disk_sb); 55 int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_devices); 56 void __cold close_ctree(struct btrfs_fs_info *fs_info); 57 int btrfs_validate_super(const struct btrfs_fs_info *fs_info, 58 const struct btrfs_super_block *sb, int mirror_num); 59 int btrfs_check_features(struct btrfs_fs_info *fs_info, bool is_rw_mount); 60 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors); 61 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev); 62 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev, 63 int copy_num, bool drop_cache); 64 int btrfs_commit_super(struct btrfs_fs_info *fs_info); 65 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root, 66 const struct btrfs_key *key); 67 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info, 68 struct btrfs_root *root); 69 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info); 70 71 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, 72 u64 objectid, bool check_ref); 73 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info, 74 u64 objectid, dev_t *anon_dev); 75 struct btrfs_root *btrfs_get_fs_root_commit_root(struct btrfs_fs_info *fs_info, 76 struct btrfs_path *path, 77 u64 objectid); 78 int btrfs_global_root_insert(struct btrfs_root *root); 79 void btrfs_global_root_delete(struct btrfs_root *root); 80 struct btrfs_root *btrfs_global_root(struct btrfs_fs_info *fs_info, 81 struct btrfs_key *key); 82 struct btrfs_root *btrfs_csum_root(struct btrfs_fs_info *fs_info, u64 bytenr); 83 struct btrfs_root *btrfs_extent_root(struct btrfs_fs_info *fs_info, u64 bytenr); 84 85 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info); 86 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info); 87 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info); 88 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info, 89 struct btrfs_root *root); 90 int btrfs_validate_extent_buffer(struct extent_buffer *eb, 91 const struct btrfs_tree_parent_check *check); 92 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS 93 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info); 94 #endif 95 96 /* 97 * This function is used to grab the root, and avoid it is freed when we 98 * access it. But it doesn't ensure that the tree is not dropped. 99 * 100 * If you want to ensure the whole tree is safe, you should use 101 * fs_info->subvol_srcu 102 */ 103 static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root) 104 { 105 if (!root) 106 return NULL; 107 if (refcount_inc_not_zero(&root->refs)) 108 return root; 109 return NULL; 110 } 111 112 void btrfs_put_root(struct btrfs_root *root); 113 void btrfs_mark_buffer_dirty(struct btrfs_trans_handle *trans, 114 struct extent_buffer *buf); 115 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid, 116 int atomic); 117 int btrfs_read_extent_buffer(struct extent_buffer *buf, 118 const struct btrfs_tree_parent_check *check); 119 120 blk_status_t btree_csum_one_bio(struct btrfs_bio *bbio); 121 int btrfs_alloc_log_tree_node(struct btrfs_trans_handle *trans, 122 struct btrfs_root *root); 123 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans, 124 struct btrfs_fs_info *fs_info); 125 int btrfs_add_log_tree(struct btrfs_trans_handle *trans, 126 struct btrfs_root *root); 127 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans, 128 struct btrfs_fs_info *fs_info); 129 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans); 130 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans, 131 u64 objectid); 132 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags); 133 int btrfs_get_free_objectid(struct btrfs_root *root, u64 *objectid); 134 int btrfs_init_root_free_objectid(struct btrfs_root *root); 135 136 #endif 137