text: /*
   * Copyright (C) 2007 Oracle.  All rights reserved.
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public
   * License v2 as published by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   *
   * You should have received a copy of the GNU General Public
   * License along with this program; if not, write to the
   * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   * Boston, MA 021110-1307, USA.
   */
  
  #ifndef __DISKIO__
  #define __DISKIO__
  
  #define BTRFS_SUPER_INFO_OFFSET (64 * 1024)
  #define BTRFS_SUPER_INFO_SIZE 4096
  
  #define BTRFS_SUPER_MIRROR_MAX	 3
  #define BTRFS_SUPER_MIRROR_SHIFT 12
  
  static inline u64 btrfs_sb_offset(int mirror)
  {
  	u64 start = 16 * 1024;
  	if (mirror)
  		return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
  	return BTRFS_SUPER_INFO_OFFSET;
  }
  
  struct btrfs_device;
  struct btrfs_fs_devices;
  
  struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
  				      u32 blocksize, u64 parent_transid);
  int readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
  			 u64 parent_transid);
  struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
  						   u64 bytenr, u32 blocksize);
  int clean_tree_block(struct btrfs_trans_handle *trans,
  		     struct btrfs_root *root, struct extent_buffer *buf);
  struct btrfs_root *open_ctree(struct super_block *sb,
  			      struct btrfs_fs_devices *fs_devices,
  			      char *options);
  int close_ctree(struct btrfs_root *root);
  int write_ctree_super(struct btrfs_trans_handle *trans,
  		      struct btrfs_root *root, int max_mirrors);
  struct buffer_head *btrfs_read_dev_super(struct block_device *bdev);
  int btrfs_commit_super(struct btrfs_root *root);
  int btrfs_error_commit_super(struct btrfs_root *root);
  struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
  					    u64 bytenr, u32 blocksize);
  struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
  					       struct btrfs_key *location);
  struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
  					      struct btrfs_key *location);
  int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
  void btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr);
  void __btrfs_btree_balance_dirty(struct btrfs_root *root, unsigned long nr);
  int btrfs_free_fs_root(struct btrfs_fs_info *fs_info, struct btrfs_root *root);
  void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
  int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid);
  int btrfs_set_buffer_uptodate(struct extent_buffer *buf);
  int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid);
  u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len);
  void btrfs_csum_final(u32 crc, char *result);
  int btrfs_bio_wq_end_io(struct btrfs_fs_info *info, struct bio *bio,
  			int metadata);
  int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode,
  			int rw, struct bio *bio, int mirror_num,
  			unsigned long bio_flags, u64 bio_offset,
  			extent_submit_bio_hook_t *submit_bio_start,
  			extent_submit_bio_hook_t *submit_bio_done);
  unsigned long btrfs_async_submit_limit(struct btrfs_fs_info *info);
  int btrfs_write_tree_block(struct extent_buffer *buf);
  int btrfs_wait_tree_block_writeback(struct extent_buffer *buf);
  int btrfs_init_log_root_tree(struct btrfs_trans_handle *trans,
  			     struct btrfs_fs_info *fs_info);
  int btrfs_add_log_tree(struct btrfs_trans_handle *trans,
  		       struct btrfs_root *root);
  int btree_lock_page_hook(struct page *page);
  
  #ifdef CONFIG_DEBUG_LOCK_ALLOC
  void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb, int level);
  #else
  static inline void btrfs_set_buffer_lockdep_class(struct extent_buffer *eb,
  						 int level)
  {
  }
  #endif
  #endif
  