fs/btrfs/disk-io.h

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