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 #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