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