You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
170 lines
5.3 KiB
170 lines
5.3 KiB
/*
|
|
* io.h --- the I/O manager abstraction
|
|
*
|
|
* Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
|
|
*
|
|
* %Begin-Header%
|
|
* This file may be redistributed under the terms of the GNU Library
|
|
* General Public License, version 2.
|
|
* %End-Header%
|
|
*/
|
|
|
|
#ifndef _EXT2FS_EXT2_IO_H
|
|
#define _EXT2FS_EXT2_IO_H
|
|
|
|
#include <ext2fs/ext2_types.h>
|
|
|
|
/*
|
|
* ext2_loff_t is defined here since unix_io.c needs it.
|
|
*/
|
|
#if defined(__GNUC__) || defined(HAS_LONG_LONG)
|
|
typedef long long ext2_loff_t;
|
|
#else
|
|
typedef long ext2_loff_t;
|
|
#endif
|
|
|
|
/* llseek.c */
|
|
ext2_loff_t ext2fs_llseek (int, ext2_loff_t, int);
|
|
|
|
typedef struct struct_io_manager *io_manager;
|
|
typedef struct struct_io_channel *io_channel;
|
|
typedef struct struct_io_stats *io_stats;
|
|
|
|
#define CHANNEL_FLAGS_WRITETHROUGH 0x01
|
|
#define CHANNEL_FLAGS_DISCARD_ZEROES 0x02
|
|
#define CHANNEL_FLAGS_BLOCK_DEVICE 0x04
|
|
|
|
#define io_channel_discard_zeroes_data(i) (i->flags & CHANNEL_FLAGS_DISCARD_ZEROES)
|
|
|
|
struct struct_io_channel {
|
|
errcode_t magic;
|
|
io_manager manager;
|
|
char *name;
|
|
int block_size;
|
|
errcode_t (*read_error)(io_channel channel,
|
|
unsigned long block,
|
|
int count,
|
|
void *data,
|
|
size_t size,
|
|
int actual_bytes_read,
|
|
errcode_t error);
|
|
errcode_t (*write_error)(io_channel channel,
|
|
unsigned long block,
|
|
int count,
|
|
const void *data,
|
|
size_t size,
|
|
int actual_bytes_written,
|
|
errcode_t error);
|
|
int refcount;
|
|
int flags;
|
|
long reserved[14];
|
|
void *private_data;
|
|
void *app_data;
|
|
int align;
|
|
};
|
|
|
|
struct struct_io_stats {
|
|
int num_fields;
|
|
int reserved;
|
|
unsigned long long bytes_read;
|
|
unsigned long long bytes_written;
|
|
};
|
|
|
|
struct struct_io_manager {
|
|
errcode_t magic;
|
|
const char *name;
|
|
errcode_t (*open)(const char *name, int flags, io_channel *channel);
|
|
errcode_t (*close)(io_channel channel);
|
|
errcode_t (*set_blksize)(io_channel channel, int blksize);
|
|
errcode_t (*read_blk)(io_channel channel, unsigned long block,
|
|
int count, void *data);
|
|
errcode_t (*write_blk)(io_channel channel, unsigned long block,
|
|
int count, const void *data);
|
|
errcode_t (*flush)(io_channel channel);
|
|
errcode_t (*write_byte)(io_channel channel, unsigned long offset,
|
|
int count, const void *data);
|
|
errcode_t (*set_option)(io_channel channel, const char *option,
|
|
const char *arg);
|
|
errcode_t (*get_stats)(io_channel channel, io_stats *io_stats);
|
|
errcode_t (*read_blk64)(io_channel channel, unsigned long long block,
|
|
int count, void *data);
|
|
errcode_t (*write_blk64)(io_channel channel, unsigned long long block,
|
|
int count, const void *data);
|
|
errcode_t (*discard)(io_channel channel, unsigned long long block,
|
|
unsigned long long count);
|
|
errcode_t (*cache_readahead)(io_channel channel,
|
|
unsigned long long block,
|
|
unsigned long long count);
|
|
errcode_t (*zeroout)(io_channel channel, unsigned long long block,
|
|
unsigned long long count);
|
|
long reserved[14];
|
|
};
|
|
|
|
#define IO_FLAG_RW 0x0001
|
|
#define IO_FLAG_EXCLUSIVE 0x0002
|
|
#define IO_FLAG_DIRECT_IO 0x0004
|
|
#define IO_FLAG_FORCE_BOUNCE 0x0008
|
|
|
|
/*
|
|
* Convenience functions....
|
|
*/
|
|
#define io_channel_close(c) ((c)->manager->close((c)))
|
|
#define io_channel_set_blksize(c,s) ((c)->manager->set_blksize((c),s))
|
|
#define io_channel_read_blk(c,b,n,d) ((c)->manager->read_blk((c),b,n,d))
|
|
#define io_channel_write_blk(c,b,n,d) ((c)->manager->write_blk((c),b,n,d))
|
|
#define io_channel_flush(c) ((c)->manager->flush((c)))
|
|
#define io_channel_bumpcount(c) ((c)->refcount++)
|
|
|
|
/* io_manager.c */
|
|
extern errcode_t io_channel_set_options(io_channel channel,
|
|
const char *options);
|
|
extern errcode_t io_channel_write_byte(io_channel channel,
|
|
unsigned long offset,
|
|
int count, const void *data);
|
|
extern errcode_t io_channel_read_blk64(io_channel channel,
|
|
unsigned long long block,
|
|
int count, void *data);
|
|
extern errcode_t io_channel_write_blk64(io_channel channel,
|
|
unsigned long long block,
|
|
int count, const void *data);
|
|
extern errcode_t io_channel_discard(io_channel channel,
|
|
unsigned long long block,
|
|
unsigned long long count);
|
|
extern errcode_t io_channel_zeroout(io_channel channel,
|
|
unsigned long long block,
|
|
unsigned long long count);
|
|
extern errcode_t io_channel_alloc_buf(io_channel channel,
|
|
int count, void *ptr);
|
|
extern errcode_t io_channel_cache_readahead(io_channel io,
|
|
unsigned long long block,
|
|
unsigned long long count);
|
|
|
|
/* unix_io.c */
|
|
extern io_manager unix_io_manager;
|
|
extern io_manager unixfd_io_manager;
|
|
|
|
/* sparse_io.c */
|
|
extern io_manager sparse_io_manager;
|
|
extern io_manager sparsefd_io_manager;
|
|
|
|
/* undo_io.c */
|
|
extern io_manager undo_io_manager;
|
|
extern errcode_t set_undo_io_backing_manager(io_manager manager);
|
|
extern errcode_t set_undo_io_backup_file(char *file_name);
|
|
|
|
/* test_io.c */
|
|
extern io_manager test_io_manager, test_io_backing_manager;
|
|
extern void (*test_io_cb_read_blk)
|
|
(unsigned long block, int count, errcode_t err);
|
|
extern void (*test_io_cb_write_blk)
|
|
(unsigned long block, int count, errcode_t err);
|
|
extern void (*test_io_cb_read_blk64)
|
|
(unsigned long long block, int count, errcode_t err);
|
|
extern void (*test_io_cb_write_blk64)
|
|
(unsigned long long block, int count, errcode_t err);
|
|
extern void (*test_io_cb_set_blksize)
|
|
(int blksize, errcode_t err);
|
|
|
|
#endif /* _EXT2FS_EXT2_IO_H */
|
|
|