[deliverable/linux.git] / include / linux / device-mapper.h

/*
 * Copyright (C) 2001 Sistina Software (UK) Limited.
 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
 *
 * This file is released under the LGPL.
 */

#ifndef _LINUX_DEVICE_MAPPER_H
#define _LINUX_DEVICE_MAPPER_H

#include <linux/bio.h>
#include <linux/blkdev.h>

struct dm_target;
struct dm_table;
struct mapped_device;
struct bio_vec;

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
 * = 1: simple remap complete
 * = 2: The target wants to push back the io
 */
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).
 * 2   : The target wants to push back the io
 */
typedef int (*dm_endio_fn) (struct dm_target *ti,
			    struct bio *bio, int error,
			    union map_info *map_context);

typedef void (*dm_flush_fn) (struct dm_target *ti);
typedef void (*dm_presuspend_fn) (struct dm_target *ti);
typedef void (*dm_postsuspend_fn) (struct dm_target *ti);
typedef int (*dm_preresume_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);

typedef int (*dm_ioctl_fn) (struct dm_target *ti, struct inode *inode,
			    struct file *filp, unsigned int cmd,
			    unsigned long arg);

typedef int (*dm_merge_fn) (struct dm_target *ti, struct bvec_merge_data *bvm,
			    struct bio_vec *biovec, int max_size);

void dm_error(const char *message);

/*
 * Combine device limits.
 */
void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev);

struct dm_dev {
	struct block_device *bdev;
	int mode;
	char name[16];
};

/*
 * 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_flush_fn flush;
	dm_presuspend_fn presuspend;
	dm_postsuspend_fn postsuspend;
	dm_preresume_fn preresume;
	dm_resume_fn resume;
	dm_status_fn status;
	dm_message_fn message;
	dm_ioctl_fn ioctl;
	dm_merge_fn merge;
};

struct io_restrictions {
	unsigned long bounce_pfn;
	unsigned long seg_boundary_mask;
	unsigned max_hw_sectors;
	unsigned max_sectors;
	unsigned max_segment_size;
	unsigned short hardsect_size;
	unsigned short max_hw_segments;
	unsigned short max_phys_segments;
	unsigned char no_cluster; /* inverted so that 0 is default */
};

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);


/*-----------------------------------------------------------------
 * Functions for creating and manipulating mapped devices.
 * Drop the reference with dm_put when you finish with the object.
 *---------------------------------------------------------------*/

/*
 * DM_ANY_MINOR chooses the next available minor number.
 */
#define DM_ANY_MINOR (-1)
int dm_create(int minor, struct mapped_device **md);

/*
 * Reference counting for md.
 */
struct mapped_device *dm_get_md(dev_t dev);
void dm_get(struct mapped_device *md);
void dm_put(struct mapped_device *md);

/*
 * An arbitrary pointer may be stored alongside a mapped device.
 */
void dm_set_mdptr(struct mapped_device *md, void *ptr);
void *dm_get_mdptr(struct mapped_device *md);

/*
 * A device can still be used while suspended, but I/O is deferred.
 */
int dm_suspend(struct mapped_device *md, unsigned suspend_flags);
int dm_resume(struct mapped_device *md);

/*
 * Event functions.
 */
uint32_t dm_get_event_nr(struct mapped_device *md);
int dm_wait_event(struct mapped_device *md, int event_nr);
uint32_t dm_next_uevent_seq(struct mapped_device *md);
void dm_uevent_add(struct mapped_device *md, struct list_head *elist);

/*
 * Info functions.
 */
const char *dm_device_name(struct mapped_device *md);
int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid);
struct gendisk *dm_disk(struct mapped_device *md);
int dm_suspended(struct mapped_device *md);
int dm_noflush_suspending(struct dm_target *ti);
union map_info *dm_get_mapinfo(struct bio *bio);

/*
 * Geometry functions.
 */
int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo);
int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo);


/*-----------------------------------------------------------------
 * Functions for manipulating device-mapper tables.
 *---------------------------------------------------------------*/

/*
 * First create an empty table.
 */
int dm_table_create(struct dm_table **result, int mode,
		    unsigned num_targets, struct mapped_device *md);

/*
 * Then call this once for each target.
 */
int dm_table_add_target(struct dm_table *t, const char *type,
			sector_t start, sector_t len, char *params);

/*
 * Finally call this to make the table ready for use.
 */
int dm_table_complete(struct dm_table *t);

/*
 * Unplug all devices in a table.
 */
void dm_table_unplug_all(struct dm_table *t);

/*
 * Table reference counting.
 */
struct dm_table *dm_get_table(struct mapped_device *md);
void dm_table_get(struct dm_table *t);
void dm_table_put(struct dm_table *t);

/*
 * Queries
 */
sector_t dm_table_get_size(struct dm_table *t);
unsigned int dm_table_get_num_targets(struct dm_table *t);
int dm_table_get_mode(struct dm_table *t);
struct mapped_device *dm_table_get_md(struct dm_table *t);

/*
 * Trigger an event.
 */
void dm_table_event(struct dm_table *t);

/*
 * The device must be suspended before calling this method.
 */
int dm_swap_table(struct mapped_device *md, struct dm_table *t);

/*
 * A wrapper around vmalloc.
 */
void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);

/*-----------------------------------------------------------------
 * Macros.
 *---------------------------------------------------------------*/
#define DM_NAME "device-mapper"

#define DMERR(f, arg...) \
	printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
#define DMERR_LIMIT(f, arg...) \
	do { \
		if (printk_ratelimit())	\
			printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " \
			       f "\n", ## arg); \
	} while (0)

#define DMWARN(f, arg...) \
	printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
#define DMWARN_LIMIT(f, arg...) \
	do { \
		if (printk_ratelimit())	\
			printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " \
			       f "\n", ## arg); \
	} while (0)

#define DMINFO(f, arg...) \
	printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
#define DMINFO_LIMIT(f, arg...) \
	do { \
		if (printk_ratelimit())	\
			printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f \
			       "\n", ## arg); \
	} while (0)

#ifdef CONFIG_DM_DEBUG
#  define DMDEBUG(f, arg...) \
	printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg)
#  define DMDEBUG_LIMIT(f, arg...) \
	do { \
		if (printk_ratelimit())	\
			printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX ": " f \
			       "\n", ## arg); \
	} while (0)
#else
#  define DMDEBUG(f, arg...) do {} while (0)
#  define DMDEBUG_LIMIT(f, arg...) do {} while (0)
#endif

#define DMEMIT(x...) sz += ((sz >= maxlen) ? \
			  0 : scnprintf(result + sz, maxlen - sz, x))

#define SECTOR_SHIFT 9

/*
 * Definitions of return values from target end_io function.
 */
#define DM_ENDIO_INCOMPLETE	1
#define DM_ENDIO_REQUEUE	2

/*
 * Definitions of return values from target map function.
 */
#define DM_MAPIO_SUBMITTED	0
#define DM_MAPIO_REMAPPED	1
#define DM_MAPIO_REQUEUE	DM_ENDIO_REQUEUE

/*
 * Ceiling(n / sz)
 */
#define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz))

#define dm_sector_div_up(n, sz) ( \
{ \
	sector_t _r = ((n) + (sz) - 1); \
	sector_div(_r, (sz)); \
	_r; \
} \
)

/*
 * ceiling(n / size) * size
 */
#define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))

static inline sector_t to_sector(unsigned long n)
{
	return (n >> SECTOR_SHIFT);
}

static inline unsigned long to_bytes(sector_t n)
{
	return (n << SECTOR_SHIFT);
}

#endif	/* _LINUX_DEVICE_MAPPER_H */
Commit	Line	Data
1da177e4 LT	1	/*
1da177e4 LT	2	* Copyright (C) 2001 Sistina Software (UK) Limited.
0da336e5	3	* Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
1da177e4 LT	4	*
	5	* This file is released under the LGPL.
	6	*/
	7
	8	#ifndef _LINUX_DEVICE_MAPPER_H
	9	#define _LINUX_DEVICE_MAPPER_H
	10
416cd17b	11	#include <linux/bio.h>
f6fccb12	12	#include <linux/blkdev.h>
416cd17b	13
1da177e4 LT	14	struct dm_target;
1da177e4 LT	15	struct dm_table;
17b2f66f	16	struct mapped_device;
f6fccb12	17	struct bio_vec;
1da177e4 LT	18
	19	typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
	20
	21	union map_info {
	22	void *ptr;
	23	unsigned long long ll;
	24	};
	25
	26	/*
	27	* In the constructor the target parameter will already have the
	28	* table, type, begin and len fields filled in.
	29	*/
	30	typedef int (dm_ctr_fn) (struct dm_target target,
	31	unsigned int argc, char **argv);
	32
	33	/*
	34	* The destructor doesn't need to free the dm_target, just
	35	* anything hidden ti->private.
	36	*/
	37	typedef void (dm_dtr_fn) (struct dm_target ti);
	38
	39	/*
	40	* The map function must return:
	41	* < 0: error
	42	* = 0: The target will handle the io by resubmitting it later
45cbcd79	43	* = 1: simple remap complete
2e93ccc1	44	* = 2: The target wants to push back the io
1da177e4 LT	45	*/
	46	typedef int (dm_map_fn) (struct dm_target ti, struct bio *bio,
	47	union map_info *map_context);
	48
	49	/*
	50	* Returns:
	51	* < 0 : error (currently ignored)
	52	* 0 : ended successfully
	53	* 1 : for some reason the io has still not completed (eg,
	54	* multipath target might want to requeue a failed io).
2e93ccc1	55	* 2 : The target wants to push back the io
1da177e4 LT	56	*/
	57	typedef int (dm_endio_fn) (struct dm_target ti,
	58	struct bio *bio, int error,
	59	union map_info *map_context);
	60
999d8168	61	typedef void (dm_flush_fn) (struct dm_target ti);
1da177e4 LT	62	typedef void (dm_presuspend_fn) (struct dm_target ti);
1da177e4 LT	63	typedef void (dm_postsuspend_fn) (struct dm_target ti);
8757b776	64	typedef int (dm_preresume_fn) (struct dm_target ti);
1da177e4 LT	65	typedef void (dm_resume_fn) (struct dm_target ti);
	66
	67	typedef int (dm_status_fn) (struct dm_target ti, status_type_t status_type,
	68	char *result, unsigned int maxlen);
	69
	70	typedef int (dm_message_fn) (struct dm_target ti, unsigned argc, char **argv);
	71
aa129a22 MB	72	typedef int (dm_ioctl_fn) (struct dm_target ti, struct inode *inode,
	73	struct file *filp, unsigned int cmd,
	74	unsigned long arg);
	75
f6fccb12 MB	76	typedef int (dm_merge_fn) (struct dm_target ti, struct bvec_merge_data *bvm,
	77	struct bio_vec *biovec, int max_size);
	78
1da177e4 LT	79	void dm_error(const char *message);
1da177e4 LT	80
3cb40214 BR	81	/*
	82	* Combine device limits.
	83	*/
	84	void dm_set_device_limits(struct dm_target ti, struct block_device bdev);
	85
82b1519b MP	86	struct dm_dev {
	87	struct block_device *bdev;
	88	int mode;
	89	char name[16];
	90	};
	91
1da177e4 LT	92	/*
	93	* Constructors should call these functions to ensure destination devices
	94	* are opened/closed correctly.
	95	* FIXME: too many arguments.
	96	*/
	97	int dm_get_device(struct dm_target ti, const char path, sector_t start,
	98	sector_t len, int mode, struct dm_dev **result);
	99	void dm_put_device(struct dm_target ti, struct dm_dev d);
	100
	101	/*
	102	* Information about a target type
	103	*/
	104	struct target_type {
	105	const char *name;
	106	struct module *module;
17b2f66f	107	unsigned version[3];
1da177e4 LT	108	dm_ctr_fn ctr;
	109	dm_dtr_fn dtr;
	110	dm_map_fn map;
	111	dm_endio_fn end_io;
999d8168	112	dm_flush_fn flush;
1da177e4 LT	113	dm_presuspend_fn presuspend;
1da177e4 LT	114	dm_postsuspend_fn postsuspend;
8757b776	115	dm_preresume_fn preresume;
1da177e4 LT	116	dm_resume_fn resume;
	117	dm_status_fn status;
	118	dm_message_fn message;
aa129a22	119	dm_ioctl_fn ioctl;
f6fccb12	120	dm_merge_fn merge;
1da177e4 LT	121	};
	122
	123	struct io_restrictions {
4f41b09f VA	124	unsigned long bounce_pfn;
	125	unsigned long seg_boundary_mask;
	126	unsigned max_hw_sectors;
	127	unsigned max_sectors;
	128	unsigned max_segment_size;
	129	unsigned short hardsect_size;
	130	unsigned short max_hw_segments;
	131	unsigned short max_phys_segments;
	132	unsigned char no_cluster; /* inverted so that 0 is default */
1da177e4 LT	133	};
	134
	135	struct dm_target {
	136	struct dm_table *table;
	137	struct target_type *type;
	138
	139	/* target limits */
	140	sector_t begin;
	141	sector_t len;
	142
	143	/* FIXME: turn this into a mask, and merge with io_restrictions */
	144	/* Always a power of 2 */
	145	sector_t split_io;
	146
	147	/*
	148	* These are automatically filled in by
	149	* dm_table_get_device.
	150	*/
	151	struct io_restrictions limits;
	152
	153	/* target specific data */
	154	void *private;
	155
	156	/* Used to provide an error string from the ctr */
	157	char *error;
	158	};
	159
	160	int dm_register_target(struct target_type *t);
	161	int dm_unregister_target(struct target_type *t);
	162
17b2f66f AK	163
	164	/*-----------------------------------------------------------------
	165	* Functions for creating and manipulating mapped devices.
	166	* Drop the reference with dm_put when you finish with the object.
	167	---------------------------------------------------------------/
	168
	169	/*
	170	* DM_ANY_MINOR chooses the next available minor number.
	171	*/
	172	#define DM_ANY_MINOR (-1)
	173	int dm_create(int minor, struct mapped_device **md);
	174
	175	/*
	176	* Reference counting for md.
	177	*/
	178	struct mapped_device *dm_get_md(dev_t dev);
	179	void dm_get(struct mapped_device *md);
	180	void dm_put(struct mapped_device *md);
	181
	182	/*
	183	* An arbitrary pointer may be stored alongside a mapped device.
	184	*/
	185	void dm_set_mdptr(struct mapped_device md, void ptr);
	186	void dm_get_mdptr(struct mapped_device md);
	187
	188	/*
	189	* A device can still be used while suspended, but I/O is deferred.
	190	*/
a3d77d35	191	int dm_suspend(struct mapped_device *md, unsigned suspend_flags);
17b2f66f AK	192	int dm_resume(struct mapped_device *md);
	193
	194	/*
	195	* Event functions.
	196	*/
	197	uint32_t dm_get_event_nr(struct mapped_device *md);
	198	int dm_wait_event(struct mapped_device *md, int event_nr);
7a8c3d3b MA	199	uint32_t dm_next_uevent_seq(struct mapped_device *md);
7a8c3d3b MA	200	void dm_uevent_add(struct mapped_device md, struct list_head elist);
17b2f66f AK	201
	202	/*
	203	* Info functions.
	204	*/
72d94861	205	const char dm_device_name(struct mapped_device md);
96a1f7db	206	int dm_copy_name_and_uuid(struct mapped_device md, char name, char *uuid);
17b2f66f AK	207	struct gendisk dm_disk(struct mapped_device md);
17b2f66f AK	208	int dm_suspended(struct mapped_device *md);
2e93ccc1	209	int dm_noflush_suspending(struct dm_target *ti);
89343da0	210	union map_info dm_get_mapinfo(struct bio bio);
17b2f66f AK	211
	212	/*
	213	* Geometry functions.
	214	*/
	215	int dm_get_geometry(struct mapped_device md, struct hd_geometry geo);
	216	int dm_set_geometry(struct mapped_device md, struct hd_geometry geo);
	217
	218
	219	/*-----------------------------------------------------------------
	220	* Functions for manipulating device-mapper tables.
	221	---------------------------------------------------------------/
	222
	223	/*
	224	* First create an empty table.
	225	*/
	226	int dm_table_create(struct dm_table **result, int mode,
	227	unsigned num_targets, struct mapped_device *md);
	228
	229	/*
	230	* Then call this once for each target.
	231	*/
	232	int dm_table_add_target(struct dm_table t, const char type,
	233	sector_t start, sector_t len, char *params);
	234
	235	/*
	236	* Finally call this to make the table ready for use.
	237	*/
	238	int dm_table_complete(struct dm_table *t);
	239
ea0ec640 MP	240	/*
	241	* Unplug all devices in a table.
	242	*/
	243	void dm_table_unplug_all(struct dm_table *t);
	244
17b2f66f AK	245	/*
	246	* Table reference counting.
	247	*/
	248	struct dm_table dm_get_table(struct mapped_device md);
	249	void dm_table_get(struct dm_table *t);
	250	void dm_table_put(struct dm_table *t);
	251
	252	/*
	253	* Queries
	254	*/
	255	sector_t dm_table_get_size(struct dm_table *t);
	256	unsigned int dm_table_get_num_targets(struct dm_table *t);
	257	int dm_table_get_mode(struct dm_table *t);
	258	struct mapped_device dm_table_get_md(struct dm_table t);
	259
	260	/*
	261	* Trigger an event.
	262	*/
	263	void dm_table_event(struct dm_table *t);
	264
	265	/*
	266	* The device must be suspended before calling this method.
	267	*/
	268	int dm_swap_table(struct mapped_device md, struct dm_table t);
	269
54160904 MP	270	/*
	271	* A wrapper around vmalloc.
	272	*/
	273	void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
	274
0da336e5 AK	275	/*-----------------------------------------------------------------
	276	* Macros.
	277	---------------------------------------------------------------/
	278	#define DM_NAME "device-mapper"
	279
	280	#define DMERR(f, arg...) \
	281	printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
	282	#define DMERR_LIMIT(f, arg...) \
	283	do { \
	284	if (printk_ratelimit()) \
	285	printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " \
	286	f "\n", ## arg); \
	287	} while (0)
	288
	289	#define DMWARN(f, arg...) \
	290	printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
	291	#define DMWARN_LIMIT(f, arg...) \
	292	do { \
	293	if (printk_ratelimit()) \
	294	printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " \
	295	f "\n", ## arg); \
	296	} while (0)
	297
	298	#define DMINFO(f, arg...) \
	299	printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
	300	#define DMINFO_LIMIT(f, arg...) \
	301	do { \
	302	if (printk_ratelimit()) \
	303	printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f \
	304	"\n", ## arg); \
	305	} while (0)
	306
	307	#ifdef CONFIG_DM_DEBUG
	308	# define DMDEBUG(f, arg...) \
	309	printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg)
	310	# define DMDEBUG_LIMIT(f, arg...) \
	311	do { \
	312	if (printk_ratelimit()) \
	313	printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX ": " f \
	314	"\n", ## arg); \
	315	} while (0)
	316	#else
	317	# define DMDEBUG(f, arg...) do {} while (0)
	318	# define DMDEBUG_LIMIT(f, arg...) do {} while (0)
	319	#endif
	320
	321	#define DMEMIT(x...) sz += ((sz >= maxlen) ? \
	322	0 : scnprintf(result + sz, maxlen - sz, x))
	323
	324	#define SECTOR_SHIFT 9
	325
	326	/*
	327	* Definitions of return values from target end_io function.
	328	*/
	329	#define DM_ENDIO_INCOMPLETE 1
	330	#define DM_ENDIO_REQUEUE 2
	331
	332	/*
	333	* Definitions of return values from target map function.
	334	*/
	335	#define DM_MAPIO_SUBMITTED 0
	336	#define DM_MAPIO_REMAPPED 1
	337	#define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE
	338
339	/*
340	* Ceiling(n / sz)
341	*/
342	#define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz))
343
344	#define dm_sector_div_up(n, sz) ( \
345	{ \
346	sector_t _r = ((n) + (sz) - 1); \
347	sector_div(_r, (sz)); \
348	_r; \
349	} \
350	)
351
352	/*
353	* ceiling(n / size) * size
354	*/
355	#define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))
356
357	static inline sector_t to_sector(unsigned long n)
358	{
359	return (n >> SECTOR_SHIFT);
360	}
361
362	static inline unsigned long to_bytes(sector_t n)
363	{
364	return (n << SECTOR_SHIFT);
365	}
366
17b2f66f	367	#endif /* _LINUX_DEVICE_MAPPER_H */