disk-io.h

   1 /*
   2  * Copyright (C) 2007 Oracle.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #ifndef __BTRFS_DISK_IO_H__
  20 #define __BTRFS_DISK_IO_H__
  21
  22 #define BTRFS_SUPER_INFO_OFFSET (64 * 1024)
  23 #define BTRFS_SUPER_INFO_SIZE 4096
  24
  25 #define BTRFS_SUPER_MIRROR_MAX   3
  26 #define BTRFS_SUPER_MIRROR_SHIFT 12
  27
  28 enum btrfs_open_ctree_flags {
  29         OPEN_CTREE_WRITES               = (1 << 0),
  30         OPEN_CTREE_PARTIAL              = (1 << 1),
  31         OPEN_CTREE_BACKUP_ROOT          = (1 << 2),
  32         OPEN_CTREE_RECOVER_SUPER        = (1 << 3),
  33         OPEN_CTREE_RESTORE              = (1 << 4),
  34         OPEN_CTREE_NO_BLOCK_GROUPS      = (1 << 5),
  35         OPEN_CTREE_EXCLUSIVE            = (1 << 6),
  36         OPEN_CTREE_NO_DEVICES           = (1 << 7),
  37 };
  38
  39 static inline u64 btrfs_sb_offset(int mirror)
  40 {
  41         u64 start = 16 * 1024;
  42         if (mirror)
  43                 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
  44         return BTRFS_SUPER_INFO_OFFSET;
  45 }
  46
  47 struct btrfs_device;
  48
  49 int read_whole_eb(struct btrfs_fs_info *info, struct extent_buffer *eb, int mirror);
  50 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
  51                                       u32 blocksize, u64 parent_transid);
  52 void readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
  53                           u64 parent_transid);
  54 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
  55                                                    u64 bytenr, u32 blocksize);
  56
  57 int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
  58                         u32 stripesize, struct btrfs_root *root,
  59                         struct btrfs_fs_info *fs_info, u64 objectid);
  60 int clean_tree_block(struct btrfs_trans_handle *trans,
  61                      struct btrfs_root *root, struct extent_buffer *buf);
  62
  63 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
  64 struct btrfs_fs_info *btrfs_new_fs_info(int writable, u64 sb_bytenr);
  65 int btrfs_check_fs_compatibility(struct btrfs_super_block *sb, int writable);
  66 int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info, u64 root_tree_bytenr,
  67                           enum btrfs_open_ctree_flags flags);
  68 void btrfs_release_all_roots(struct btrfs_fs_info *fs_info);
  69 void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info);
  70 int btrfs_scan_fs_devices(int fd, const char *path,
  71                           struct btrfs_fs_devices **fs_devices, u64 sb_bytenr,
  72                           int super_recover, int skip_devices);
  73 int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info);
  74
  75 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr,
  76                               enum btrfs_open_ctree_flags flags);
  77 struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
  78                                  enum btrfs_open_ctree_flags flags);
  79 struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
  80                                          u64 sb_bytenr, u64 root_tree_bytenr,
  81                                          enum btrfs_open_ctree_flags flags);
  82 int close_ctree(struct btrfs_root *root);
  83 int write_all_supers(struct btrfs_root *root);
  84 int write_ctree_super(struct btrfs_trans_handle *trans,
  85                       struct btrfs_root *root);
  86 int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr,
  87                          int super_recover);
  88 int btrfs_map_bh_to_logical(struct btrfs_root *root, struct extent_buffer *bh,
  89                             u64 logical);
  90 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
  91                                             u64 bytenr, u32 blocksize);
  92 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
  93                                       struct btrfs_key *location);
  94 struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
  95                                                struct btrfs_key *location);
  96 int btrfs_free_fs_root(struct btrfs_root *root);
  97 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
  98 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid);
  99 int btrfs_set_buffer_uptodate(struct extent_buffer *buf);
 100 int wait_on_tree_block_writeback(struct btrfs_root *root,
 101                                  struct extent_buffer *buf);
 102 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len);
 103 void btrfs_csum_final(u32 crc, char *result);
 104
 105 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
 106                              struct btrfs_root *root);
 107 int btrfs_open_device(struct btrfs_device *dev);
 108 int csum_tree_block_size(struct extent_buffer *buf, u16 csum_sectorsize,
 109                          int verify);
 110 int verify_tree_block_csum_silent(struct extent_buffer *buf, u16 csum_size);
 111 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid);
 112 int write_and_map_eb(struct btrfs_trans_handle *trans, struct btrfs_root *root,
 113                      struct extent_buffer *eb);
 114
 115 /* raid6.c */
 116 void raid6_gen_syndrome(int disks, size_t bytes, void **ptrs);
 117
 118 #endif