btrfs-progs/disk-io.h

196 lines
6.9 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"
#include "sizes.h"
#define BTRFS_SUPER_INFO_OFFSET SZ_64K
#define BTRFS_SUPER_INFO_SIZE 4096
#define BTRFS_SUPER_MIRROR_MAX 3
#define BTRFS_SUPER_MIRROR_SHIFT 12
enum btrfs_open_ctree_flags {
/* Open filesystem for writes */
OPEN_CTREE_WRITES = (1U << 0),
/* Allow to open filesystem with some broken tree roots (eg log root) */
OPEN_CTREE_PARTIAL = (1U << 1),
/* If primary root pinters are invalid, try backup copies */
OPEN_CTREE_BACKUP_ROOT = (1U << 2),
/* Allow reading all superblock sopies if the primary is damaged */
OPEN_CTREE_RECOVER_SUPER = (1U << 3),
/* Restoring filesystem image */
OPEN_CTREE_RESTORE = (1U << 4),
/* Do not read block groups (extent tree) */
OPEN_CTREE_NO_BLOCK_GROUPS = (1U << 5),
/* Open all devices in O_EXCL mode */
OPEN_CTREE_EXCLUSIVE = (1U << 6),
/* Do not scan devices */
OPEN_CTREE_NO_DEVICES = (1U << 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 = (1U << 8),
/* Return the chunk root */
__OPEN_CTREE_RETURN_CHUNK_ROOT = (1U << 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
*/
/* Ignore UUID mismatches */
OPEN_CTREE_IGNORE_FSID_MISMATCH = (1U << 10),
/*
* Allow open_ctree_fs_info() to return an incomplete fs_info with
* system chunks from super block only.
* It's useful when chunks are corrupted.
* Makes no sense for open_ctree variants returning btrfs_root.
*/
OPEN_CTREE_IGNORE_CHUNK_TREE_ERROR = (1U << 11),
/* Allow to open a partially created filesystem */
OPEN_CTREE_FS_PARTIAL = (1U << 12),
/*
* Invalidate the free space tree (i.e., clear the FREE_SPACE_TREE_VALID
* compat_ro bit).
*/
OPEN_CTREE_INVALIDATE_FST = (1U << 13),
};
/*
* Modes of superblock access
*/
enum btrfs_read_sb_flags {
SBREAD_DEFAULT = 0,
/* Reading superblock during recovery */
SBREAD_RECOVER = (1 << 0),
/*
* Read superblock with the fake signature, cannot be used with
* SBREAD_RECOVER
*/
SBREAD_PARTIAL = (1 << 1),
};
/*
* Use macro to define mirror super block position,
* so we can use it in static array initialization
*/
#define BTRFS_SB_MIRROR_OFFSET(mirror) ((u64)(SZ_16K) << \
(BTRFS_SUPER_MIRROR_SHIFT * (mirror)))
static inline u64 btrfs_sb_offset(int mirror)
{
if (mirror)
return BTRFS_SB_MIRROR_OFFSET(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(struct btrfs_fs_info *fs_info, u64 bytenr,
u64 parent_transid);
int check_tree_block(struct btrfs_fs_info *fs_info,
struct extent_buffer *buf);
int read_extent_data(struct btrfs_fs_info *fs_info, char *data, u64 logical,
u64 *len, int mirror);
void readahead_tree_block(struct btrfs_fs_info *fs_info, u64 bytenr,
u64 parent_transid);
struct extent_buffer* btrfs_find_create_tree_block(
struct btrfs_fs_info *fs_info, u64 bytenr);
void btrfs_setup_root(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,
unsigned int flags);
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_fs_info *fs_info);
int write_ctree_super(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info);
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_fs_info *fs_info,
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);
u32 btrfs_csum_data(char *data, u32 seed, size_t len);
void btrfs_csum_final(u32 crc, u8 *result);
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_fs_info *fs_info,
struct extent_buffer *eb);
int write_and_map_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb);
#endif