btrfs-progs/disk-io.h
David Sterba 059832da5f btrfs-progs: make superblock reading/scanning api more generic
We'll add more modes that affect scanning.

Signed-off-by: David Sterba <dsterba@suse.com>
2016-08-24 14:36:58 +02:00

179 lines
6.5 KiB
C

/*
* 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 __BTRFS_DISK_IO_H__
#define __BTRFS_DISK_IO_H__
#include "kerncompat.h"
#include "ctree.h"
#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
enum btrfs_open_ctree_flags {
OPEN_CTREE_WRITES = (1 << 0),
OPEN_CTREE_PARTIAL = (1 << 1),
OPEN_CTREE_BACKUP_ROOT = (1 << 2),
OPEN_CTREE_RECOVER_SUPER = (1 << 3),
OPEN_CTREE_RESTORE = (1 << 4),
OPEN_CTREE_NO_BLOCK_GROUPS = (1 << 5),
OPEN_CTREE_EXCLUSIVE = (1 << 6),
OPEN_CTREE_NO_DEVICES = (1 << 7),
/*
* Don't print error messages if bytenr or checksums do not match in
* tree block headers. Turn on by OPEN_CTREE_SUPPRESS_ERROR
*/
OPEN_CTREE_SUPPRESS_CHECK_BLOCK_ERRORS = (1 << 8),
/* Return chunk root */
__OPEN_CTREE_RETURN_CHUNK_ROOT = (1 << 9),
OPEN_CTREE_CHUNK_ROOT_ONLY = OPEN_CTREE_PARTIAL +
OPEN_CTREE_SUPPRESS_CHECK_BLOCK_ERRORS +
__OPEN_CTREE_RETURN_CHUNK_ROOT,
/*
* TODO: cleanup: Split the open_ctree_flags into more independent
* Tree bits.
* Like split PARTIAL into SKIP_CSUM/SKIP_EXTENT
*/
OPEN_CTREE_IGNORE_FSID_MISMATCH = (1 << 10),
/*
* Allow open_ctree_fs_info() to return a incomplete fs_info with
* system chunks from super block only.
* It's useful for chunk corruption case.
* Makes no sense for open_ctree variants returning btrfs_root.
*/
OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR = (1 << 11)
};
/*
* Modes of superblock access
*/
enum btrfs_read_sb_flags {
SBREAD_DEFAULT = 0,
/* Reading superblock during recovery */
SBREAD_RECOVER = (1 << 0),
};
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;
int read_whole_eb(struct btrfs_fs_info *info, struct extent_buffer *eb, int mirror);
struct extent_buffer* read_tree_block_fs_info(
struct btrfs_fs_info *fs_info, u64 bytenr, u32 blocksize,
u64 parent_transid);
static inline struct extent_buffer* read_tree_block(
struct btrfs_root *root, u64 bytenr, u32 blocksize,
u64 parent_transid)
{
return read_tree_block_fs_info(root->fs_info, bytenr, blocksize,
parent_transid);
}
int read_extent_data(struct btrfs_root *root, char *data, u64 logical,
u64 *len, int mirror);
void readahead_tree_block(struct btrfs_root *root, u64 bytenr, u32 blocksize,
u64 parent_transid);
struct extent_buffer* btrfs_find_create_tree_block(
struct btrfs_fs_info *fs_info, u64 bytenr, u32 blocksize);
int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
u32 stripesize, struct btrfs_root *root,
struct btrfs_fs_info *fs_info, u64 objectid);
int clean_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct extent_buffer *buf);
void btrfs_free_fs_info(struct btrfs_fs_info *fs_info);
struct btrfs_fs_info *btrfs_new_fs_info(int writable, u64 sb_bytenr);
int btrfs_check_fs_compatibility(struct btrfs_super_block *sb, int writable);
int btrfs_setup_all_roots(struct btrfs_fs_info *fs_info, u64 root_tree_bytenr,
unsigned flags);
void btrfs_release_all_roots(struct btrfs_fs_info *fs_info);
void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info);
int btrfs_scan_fs_devices(int fd, const char *path,
struct btrfs_fs_devices **fs_devices, u64 sb_bytenr,
unsigned sbflags, int skip_devices);
int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info,
u64 chunk_root_bytenr);
struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr,
unsigned flags);
struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr,
unsigned flags);
struct btrfs_fs_info *open_ctree_fs_info(const char *filename,
u64 sb_bytenr, u64 root_tree_bytenr,
u64 chunk_root_bytenr,
unsigned flags);
int close_ctree_fs_info(struct btrfs_fs_info *fs_info);
static inline int close_ctree(struct btrfs_root *root)
{
if (!root)
return 0;
return close_ctree_fs_info(root->fs_info);
}
int write_all_supers(struct btrfs_root *root);
int write_ctree_super(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr,
unsigned sbflags);
int btrfs_map_bh_to_logical(struct btrfs_root *root, struct extent_buffer *bh,
u64 logical);
struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
u64 bytenr, u32 blocksize);
struct btrfs_root *btrfs_read_fs_root(struct btrfs_fs_info *fs_info,
struct btrfs_key *location);
struct btrfs_root *btrfs_read_fs_root_no_cache(struct btrfs_fs_info *fs_info,
struct btrfs_key *location);
int btrfs_free_fs_root(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 wait_on_tree_block_writeback(struct btrfs_root *root,
struct extent_buffer *buf);
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_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btrfs_open_device(struct btrfs_device *dev);
int csum_tree_block_size(struct extent_buffer *buf, u16 csum_sectorsize,
int verify);
int verify_tree_block_csum_silent(struct extent_buffer *buf, u16 csum_size);
int btrfs_read_buffer(struct extent_buffer *buf, u64 parent_transid);
int write_tree_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *eb);
int write_and_map_eb(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *eb);
/* raid6.c */
void raid6_gen_syndrome(int disks, size_t bytes, void **ptrs);
#endif