131 lines
3.2 KiB
C
131 lines
3.2 KiB
C
|
/*
|
||
|
|
* Copyright (C) 2001 Sistina Software (UK) Limited.
|
||
|
|
* Copyright (C) 2004 Red Hat, Inc. All rights reserved.
|
||
|
|
*
|
||
|
|
* This file is released under the LGPL.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#ifndef _LINUX_DEVICE_MAPPER_H
|
||
|
|
#define _LINUX_DEVICE_MAPPER_H
|
||
|
|
|
||
|
|
struct dm_target;
|
||
|
|
struct dm_table;
|
||
|
|
struct dm_dev;
|
||
|
|
|
||
|
|
typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
|
||
|
|
|
||
|
|
union map_info {
|
||
|
|
void *ptr;
|
||
|
|
unsigned long long ll;
|
||
|
|
};
|
||
|
|
|
||
|
|
/*
|
||
|
|
* In the constructor the target parameter will already have the
|
||
|
|
* table, type, begin and len fields filled in.
|
||
|
|
*/
|
||
|
|
typedef int (*dm_ctr_fn) (struct dm_target *target,
|
||
|
|
unsigned int argc, char **argv);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* The destructor doesn't need to free the dm_target, just
|
||
|
|
* anything hidden ti->private.
|
||
|
|
*/
|
||
|
|
typedef void (*dm_dtr_fn) (struct dm_target *ti);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* The map function must return:
|
||
|
|
* < 0: error
|
||
|
|
* = 0: The target will handle the io by resubmitting it later
|
||
|
|
* > 0: simple remap complete
|
||
|
|
*/
|
||
|
|
typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio,
|
||
|
|
union map_info *map_context);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Returns:
|
||
|
|
* < 0 : error (currently ignored)
|
||
|
|
* 0 : ended successfully
|
||
|
|
* 1 : for some reason the io has still not completed (eg,
|
||
|
|
* multipath target might want to requeue a failed io).
|
||
|
|
*/
|
||
|
|
typedef int (*dm_endio_fn) (struct dm_target *ti,
|
||
|
|
struct bio *bio, int error,
|
||
|
|
union map_info *map_context);
|
||
|
|
|
||
|
|
typedef void (*dm_presuspend_fn) (struct dm_target *ti);
|
||
|
|
typedef void (*dm_postsuspend_fn) (struct dm_target *ti);
|
||
|
|
typedef void (*dm_resume_fn) (struct dm_target *ti);
|
||
|
|
|
||
|
|
typedef int (*dm_status_fn) (struct dm_target *ti, status_type_t status_type,
|
||
|
|
char *result, unsigned int maxlen);
|
||
|
|
|
||
|
|
typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv);
|
||
|
|
|
||
|
|
void dm_error(const char *message);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Constructors should call these functions to ensure destination devices
|
||
|
|
* are opened/closed correctly.
|
||
|
|
* FIXME: too many arguments.
|
||
|
|
*/
|
||
|
|
int dm_get_device(struct dm_target *ti, const char *path, sector_t start,
|
||
|
|
sector_t len, int mode, struct dm_dev **result);
|
||
|
|
void dm_put_device(struct dm_target *ti, struct dm_dev *d);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Information about a target type
|
||
|
|
*/
|
||
|
|
struct target_type {
|
||
|
|
const char *name;
|
||
|
|
struct module *module;
|
||
|
|
unsigned version[3];
|
||
|
|
dm_ctr_fn ctr;
|
||
|
|
dm_dtr_fn dtr;
|
||
|
|
dm_map_fn map;
|
||
|
|
dm_endio_fn end_io;
|
||
|
|
dm_presuspend_fn presuspend;
|
||
|
|
dm_postsuspend_fn postsuspend;
|
||
|
|
dm_resume_fn resume;
|
||
|
|
dm_status_fn status;
|
||
|
|
dm_message_fn message;
|
||
|
|
};
|
||
|
|
|
||
|
|
struct io_restrictions {
|
||
|
|
unsigned short max_sectors;
|
||
|
|
unsigned short max_phys_segments;
|
||
|
|
unsigned short max_hw_segments;
|
||
|
|
unsigned short hardsect_size;
|
||
|
|
unsigned int max_segment_size;
|
||
|
|
unsigned long seg_boundary_mask;
|
||
|
|
};
|
||
|
|
|
||
|
|
struct dm_target {
|
||
|
|
struct dm_table *table;
|
||
|
|
struct target_type *type;
|
||
|
|
|
||
|
|
/* target limits */
|
||
|
|
sector_t begin;
|
||
|
|
sector_t len;
|
||
|
|
|
||
|
|
/* FIXME: turn this into a mask, and merge with io_restrictions */
|
||
|
|
/* Always a power of 2 */
|
||
|
|
sector_t split_io;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* These are automatically filled in by
|
||
|
|
* dm_table_get_device.
|
||
|
|
*/
|
||
|
|
struct io_restrictions limits;
|
||
|
|
|
||
|
|
/* target specific data */
|
||
|
|
void *private;
|
||
|
|
|
||
|
|
/* Used to provide an error string from the ctr */
|
||
|
|
char *error;
|
||
|
|
};
|
||
|
|
|
||
|
|
int dm_register_target(struct target_type *t);
|
||
|
|
int dm_unregister_target(struct target_type *t);
|
||
|
|
|
||
|
|
#endif /* _LINUX_DEVICE_MAPPER_H */
|