btrfs-progs: kill BUG_ON in readahead_tree_block()
[platform/upstream/btrfs-progs.git] / 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 __DISKIO__
20 #define __DISKIO__
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,
30         OPEN_CTREE_PARTIAL              = 2,
31         OPEN_CTREE_BACKUP_ROOT          = 4,
32         OPEN_CTREE_RECOVER_SUPER        = 8,
33         OPEN_CTREE_RESTORE              = 16,
34         OPEN_CTREE_NO_BLOCK_GROUPS      = 32,
35         OPEN_CTREE_EXCLUSIVE            = 64,
36 };
37
38 static inline u64 btrfs_sb_offset(int mirror)
39 {
40         u64 start = 16 * 1024;
41         if (mirror)
42                 return start << (BTRFS_SUPER_MIRROR_SHIFT * mirror);
43         return BTRFS_SUPER_INFO_OFFSET;
44 }
45
46 struct btrfs_device;
47
48 int read_whole_eb(struct btrfs_fs_info *info, struct extent_buffer *eb, int mirror);
49 struct extent_buffer *read_tree_block(struct btrfs_root *root, u64 bytenr,
50                                       u32 blocksize, u64 parent_transid);
51 void readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
52                           u64 parent_transid);
53 struct extent_buffer *btrfs_find_create_tree_block(struct btrfs_root *root,
54                                                    u64 bytenr, u32 blocksize);
55
56 int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
57                         u32 stripesize, struct btrfs_root *root,
58                         struct btrfs_fs_info *fs_info, u64 objectid);
59 int clean_tree_block(struct btrfs_trans_handle *trans,
60                      struct btrfs_root *root, struct extent_buffer *buf);
61
62 void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
63 struct btrfs_fs_info *btrfs_new_fs_info(int writable, u64 sb_bytenr);
64 int btrfs_check_fs_compatibility(struct btrfs_super_block *sb, int writable);
65 int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info, u64 root_tree_bytenr,
66                           enum btrfs_open_ctree_flags flags);
67 void btrfs_release_all_roots(struct btrfs_fs_info *fs_info);
68 void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info);
69 int btrfs_scan_fs_devices(int fd, const char *path,
70                           struct btrfs_fs_devices **fs_devices, u64 sb_bytenr,
71                           int run_ioctl, int super_recover);
72 int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info);
73
74 struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr,
75                               enum btrfs_open_ctree_flags flags);
76 struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
77                                  enum btrfs_open_ctree_flags flags);
78 struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
79                                          u64 sb_bytenr, u64 root_tree_bytenr,
80                                          enum btrfs_open_ctree_flags flags);
81 int close_ctree(struct btrfs_root *root);
82 int write_all_supers(struct btrfs_root *root);
83 int write_ctree_super(struct btrfs_trans_handle *trans,
84                       struct btrfs_root *root);
85 int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr,
86                          int super_recover);
87 int btrfs_map_bh_to_logical(struct btrfs_root *root, struct extent_buffer *bh,
88                             u64 logical);
89 struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
90                                             u64 bytenr, u32 blocksize);
91 struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
92                                       struct btrfs_key *location);
93 struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
94                                                struct btrfs_key *location);
95 int btrfs_free_fs_root(struct btrfs_root *root);
96 void btrfs_mark_buffer_dirty(struct extent_buffer *buf);
97 int btrfs_buffer_uptodate(struct extent_buffer *buf, u64 parent_transid);
98 int btrfs_set_buffer_uptodate(struct extent_buffer *buf);
99 int wait_on_tree_block_writeback(struct btrfs_root *root,
100                                  struct extent_buffer *buf);
101 u32 btrfs_csum_data(struct btrfs_root *root, char *data, u32 seed, size_t len);
102 void btrfs_csum_final(u32 crc, char *result);
103
104 int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
105                              struct btrfs_root *root);
106 int btrfs_open_device(struct btrfs_device *dev);
107 int csum_tree_block_size(struct extent_buffer *buf, u16 csum_sectorsize,
108                          int verify);
109 int verify_tree_block_csum_silent(struct extent_buffer *buf, u16 csum_size);
110 int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid);
111 int write_and_map_eb(struct btrfs_trans_handle *trans, struct btrfs_root *root,
112                      struct extent_buffer *eb);
113 #endif
114
115 /* raid6.c */
116 void raid6_gen_syndrome(int disks, size_t bytes, void **ptrs);