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_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 };
  29
  30 static 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
  38 struct btrfs_device;
  39 struct btrfs_fs_devices;
  40
  41 void btrfs_check_leaked_roots(struct btrfs_fs_info *fs_info);
  42 void btrfs_init_fs_info(struct btrfs_fs_info *fs_info);
  43 int btrfs_verify_level_key(struct extent_buffer *eb, int level,
  44                            struct btrfs_key *first_key, u64 parent_transid);
  45 struct 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);
  48 void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr);
  49 struct extent_buffer *btrfs_find_create_tree_block(
  50                                                 struct btrfs_fs_info *fs_info,
  51                                                 u64 bytenr);
  52 void btrfs_clean_tree_block(struct extent_buffer *buf);
  53 int __cold open_ctree(struct super_block *sb,
  54                struct btrfs_fs_devices *fs_devices,
  55                char *options);
  56 void __cold close_ctree(struct btrfs_fs_info *fs_info);
  57 int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors);
  58 struct btrfs_super_block *btrfs_read_dev_super(struct block_device *bdev);
  59 struct btrfs_super_block *btrfs_read_dev_one_super(struct block_device *bdev,
  60                                                    int copy_num);
  61 int btrfs_commit_super(struct btrfs_fs_info *fs_info);
  62 struct btrfs_root *btrfs_read_tree_root(struct btrfs_root *tree_root,
  63                                         struct btrfs_key *key);
  64 int btrfs_insert_fs_root(struct btrfs_fs_info *fs_info,
  65                          struct btrfs_root *root);
  66 void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info);
  67
  68 struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info,
  69                                      u64 objectid, bool check_ref);
  70 struct btrfs_root *btrfs_get_new_fs_root(struct btrfs_fs_info *fs_info,
  71                                          u64 objectid, dev_t anon_dev);
  72
  73 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
  74 int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
  75 void btrfs_btree_balance_dirty(struct btrfs_fs_info *fs_info);
  76 void btrfs_btree_balance_dirty_nodelay(struct btrfs_fs_info *fs_info);
  77 void btrfs_drop_and_free_fs_root(struct btrfs_fs_info *fs_info,
  78                                  struct btrfs_root *root);
  79
  80 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
  81 struct btrfs_root *btrfs_alloc_dummy_root(struct btrfs_fs_info *fs_info);
  82 #endif
  83
  84 /*
  85  * This function is used to grab the root, and avoid it is freed when we
  86  * access it. But it doesn't ensure that the tree is not dropped.
  87  *
  88  * If you want to ensure the whole tree is safe, you should use
  89  *      fs_info->subvol_srcu
  90  */
  91 static inline struct btrfs_root *btrfs_grab_root(struct btrfs_root *root)
  92 {
  93         if (!root)
  94                 return NULL;
  95         if (refcount_inc_not_zero(&root->refs))
  96                 return root;
  97         return NULL;
  98 }
  99
 100 void btrfs_put_root(struct btrfs_root *root);
 101 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
 102 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid,
 103                           int atomic);
 104 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid, int level,
 105                       struct btrfs_key *first_key);
 106 blk_status_t btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
 107                         enum btrfs_wq_endio_type metadata);
 108 blk_status_t btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio,
 109                         int mirror_num, unsigned long bio_flags,
 110                         u64 bio_offset, void *private_data,
 111                         extent_submit_bio_start_t *submit_bio_start);
 112 blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
 113                           int mirror_num);
 114 int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
 115                              struct btrfs_fs_info *fs_info);
 116 int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
 117                        struct btrfs_root *root);
 118 void btrfs_cleanup_dirty_bgs(struct btrfs_transaction *trans,
 119                              struct btrfs_fs_info *fs_info);
 120 void btrfs_cleanup_one_transaction(struct btrfs_transaction *trans,
 121                                   struct btrfs_fs_info *fs_info);
 122 struct btrfs_root *btrfs_create_tree(struct btrfs_trans_handle *trans,
 123                                      u64 objectid);
 124 int btree_lock_page_hook(struct page *page, void *data,
 125                                 void (*flush_fn)(void *));
 126 struct extent_map *btree_get_extent(struct btrfs_inode *inode,
 127                                     struct page *page, size_t pg_offset,
 128                                     u64 start, u64 len);
 129 int btrfs_get_num_tolerated_disk_barrier_failures(u64 flags);
 130 int __init btrfs_end_io_wq_init(void);
 131 void __cold btrfs_end_io_wq_exit(void);
 132
 133 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 134 void btrfs_init_lockdep(void);
 135 void btrfs_set_buffer_lockdep_class(u64 objectid,
 136                                     struct extent_buffer *eb, int level);
 137 #else
 138 static inline void btrfs_init_lockdep(void)
 139 { }
 140 static inline void btrfs_set_buffer_lockdep_class(u64 objectid,
 141                                         struct extent_buffer *eb, int level)
 142 {
 143 }
 144 #endif
 145
 146 #endif