[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);
typedef int (*dm_map_request_fn) (struct dm_target *ti, struct request *clone,
				  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 int (*dm_request_endio_fn) (struct dm_target *ti,
				    struct request *clone, 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, 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);

/*
 * Returns:
 *    0: The target can handle the next I/O immediately.
 *    1: The target can't handle the next I/O immediately.
 */
typedef int (*dm_busy_fn) (struct dm_target *ti);

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;
	fmode_t 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, fmode_t mode, struct dm_dev **result);
void dm_put_device(struct dm_target *ti, struct dm_dev *d);

/*
 * Information about a target type
 */

/*
 * Target features
 */

struct target_type {
	uint64_t features;
	const char *name;
	struct module *module;
	unsigned version[3];
	dm_ctr_fn ctr;
	dm_dtr_fn dtr;
	dm_map_fn map;
	dm_map_request_fn map_rq;
	dm_endio_fn end_io;
	dm_request_endio_fn rq_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;
	dm_busy_fn busy;

	/* For internal device-mapper use. */
	struct list_head list;
};

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);
void 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, fmode_t 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);
fmode_t 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 DMCRIT(f, arg...) \
	printk(KERN_CRIT DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)

#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))

#define dm_array_too_big(fixed, obj, num) \
	((num) > (UINT_MAX - (fixed)) / (obj))

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);
7d76345d KU	48	typedef int (dm_map_request_fn) (struct dm_target ti, struct request *clone,
7d76345d KU	49	union map_info *map_context);
1da177e4 LT	50
	51	/*
	52	* Returns:
	53	* < 0 : error (currently ignored)
	54	* 0 : ended successfully
	55	* 1 : for some reason the io has still not completed (eg,
	56	* multipath target might want to requeue a failed io).
2e93ccc1	57	* 2 : The target wants to push back the io
1da177e4 LT	58	*/
	59	typedef int (dm_endio_fn) (struct dm_target ti,
	60	struct bio *bio, int error,
	61	union map_info *map_context);
7d76345d KU	62	typedef int (dm_request_endio_fn) (struct dm_target ti,
	63	struct request *clone, int error,
	64	union map_info *map_context);
1da177e4	65
999d8168	66	typedef void (dm_flush_fn) (struct dm_target ti);
1da177e4 LT	67	typedef void (dm_presuspend_fn) (struct dm_target ti);
1da177e4 LT	68	typedef void (dm_postsuspend_fn) (struct dm_target ti);
8757b776	69	typedef int (dm_preresume_fn) (struct dm_target ti);
1da177e4 LT	70	typedef void (dm_resume_fn) (struct dm_target ti);
	71
	72	typedef int (dm_status_fn) (struct dm_target ti, status_type_t status_type,
	73	char *result, unsigned int maxlen);
	74
	75	typedef int (dm_message_fn) (struct dm_target ti, unsigned argc, char **argv);
	76
647b3d00	77	typedef int (dm_ioctl_fn) (struct dm_target ti, unsigned int cmd,
aa129a22 MB	78	unsigned long arg);
aa129a22 MB	79
f6fccb12 MB	80	typedef int (dm_merge_fn) (struct dm_target ti, struct bvec_merge_data *bvm,
	81	struct bio_vec *biovec, int max_size);
	82
7d76345d KU	83	/*
	84	* Returns:
	85	* 0: The target can handle the next I/O immediately.
	86	* 1: The target can't handle the next I/O immediately.
	87	*/
	88	typedef int (dm_busy_fn) (struct dm_target ti);
	89
1da177e4 LT	90	void dm_error(const char *message);
1da177e4 LT	91
3cb40214 BR	92	/*
	93	* Combine device limits.
	94	*/
	95	void dm_set_device_limits(struct dm_target ti, struct block_device bdev);
	96
82b1519b MP	97	struct dm_dev {
82b1519b MP	98	struct block_device *bdev;
aeb5d727	99	fmode_t mode;
82b1519b MP	100	char name[16];
	101	};
	102
1da177e4 LT	103	/*
	104	* Constructors should call these functions to ensure destination devices
	105	* are opened/closed correctly.
	106	* FIXME: too many arguments.
	107	*/
	108	int dm_get_device(struct dm_target ti, const char path, sector_t start,
aeb5d727	109	sector_t len, fmode_t mode, struct dm_dev **result);
1da177e4 LT	110	void dm_put_device(struct dm_target ti, struct dm_dev d);
	111
	112	/*
	113	* Information about a target type
	114	*/
ab4c1424 AK	115
	116	/*
	117	* Target features
	118	*/
ab4c1424	119
1da177e4	120	struct target_type {
ab4c1424	121	uint64_t features;
1da177e4 LT	122	const char *name;
1da177e4 LT	123	struct module *module;
17b2f66f	124	unsigned version[3];
1da177e4 LT	125	dm_ctr_fn ctr;
	126	dm_dtr_fn dtr;
	127	dm_map_fn map;
7d76345d	128	dm_map_request_fn map_rq;
1da177e4	129	dm_endio_fn end_io;
7d76345d	130	dm_request_endio_fn rq_end_io;
999d8168	131	dm_flush_fn flush;
1da177e4 LT	132	dm_presuspend_fn presuspend;
1da177e4 LT	133	dm_postsuspend_fn postsuspend;
8757b776	134	dm_preresume_fn preresume;
1da177e4 LT	135	dm_resume_fn resume;
	136	dm_status_fn status;
	137	dm_message_fn message;
aa129a22	138	dm_ioctl_fn ioctl;
f6fccb12	139	dm_merge_fn merge;
7d76345d	140	dm_busy_fn busy;
45194e4f CR	141
	142	/* For internal device-mapper use. */
	143	struct list_head list;
1da177e4 LT	144	};
	145
	146	struct io_restrictions {
4f41b09f VA	147	unsigned long bounce_pfn;
	148	unsigned long seg_boundary_mask;
	149	unsigned max_hw_sectors;
	150	unsigned max_sectors;
	151	unsigned max_segment_size;
	152	unsigned short hardsect_size;
	153	unsigned short max_hw_segments;
	154	unsigned short max_phys_segments;
	155	unsigned char no_cluster; /* inverted so that 0 is default */
1da177e4 LT	156	};
	157
	158	struct dm_target {
	159	struct dm_table *table;
	160	struct target_type *type;
	161
	162	/* target limits */
	163	sector_t begin;
	164	sector_t len;
	165
	166	/* FIXME: turn this into a mask, and merge with io_restrictions */
	167	/* Always a power of 2 */
	168	sector_t split_io;
	169
	170	/*
	171	* These are automatically filled in by
	172	* dm_table_get_device.
	173	*/
	174	struct io_restrictions limits;
	175
	176	/* target specific data */
	177	void *private;
	178
	179	/* Used to provide an error string from the ctr */
	180	char *error;
	181	};
	182
	183	int dm_register_target(struct target_type *t);
10d3bd09	184	void dm_unregister_target(struct target_type *t);
17b2f66f AK	185
	186	/*-----------------------------------------------------------------
	187	* Functions for creating and manipulating mapped devices.
	188	* Drop the reference with dm_put when you finish with the object.
	189	---------------------------------------------------------------/
	190
	191	/*
	192	* DM_ANY_MINOR chooses the next available minor number.
	193	*/
	194	#define DM_ANY_MINOR (-1)
	195	int dm_create(int minor, struct mapped_device **md);
	196
	197	/*
	198	* Reference counting for md.
	199	*/
	200	struct mapped_device *dm_get_md(dev_t dev);
	201	void dm_get(struct mapped_device *md);
	202	void dm_put(struct mapped_device *md);
	203
	204	/*
	205	* An arbitrary pointer may be stored alongside a mapped device.
	206	*/
	207	void dm_set_mdptr(struct mapped_device md, void ptr);
	208	void dm_get_mdptr(struct mapped_device md);
	209
	210	/*
	211	* A device can still be used while suspended, but I/O is deferred.
	212	*/
a3d77d35	213	int dm_suspend(struct mapped_device *md, unsigned suspend_flags);
17b2f66f AK	214	int dm_resume(struct mapped_device *md);
	215
	216	/*
	217	* Event functions.
	218	*/
	219	uint32_t dm_get_event_nr(struct mapped_device *md);
	220	int dm_wait_event(struct mapped_device *md, int event_nr);
7a8c3d3b MA	221	uint32_t dm_next_uevent_seq(struct mapped_device *md);
7a8c3d3b MA	222	void dm_uevent_add(struct mapped_device md, struct list_head elist);
17b2f66f AK	223
	224	/*
	225	* Info functions.
	226	*/
72d94861	227	const char dm_device_name(struct mapped_device md);
96a1f7db	228	int dm_copy_name_and_uuid(struct mapped_device md, char name, char *uuid);
17b2f66f AK	229	struct gendisk dm_disk(struct mapped_device md);
17b2f66f AK	230	int dm_suspended(struct mapped_device *md);
2e93ccc1	231	int dm_noflush_suspending(struct dm_target *ti);
89343da0	232	union map_info dm_get_mapinfo(struct bio bio);
17b2f66f AK	233
	234	/*
	235	* Geometry functions.
	236	*/
	237	int dm_get_geometry(struct mapped_device md, struct hd_geometry geo);
	238	int dm_set_geometry(struct mapped_device md, struct hd_geometry geo);
	239
	240
	241	/*-----------------------------------------------------------------
	242	* Functions for manipulating device-mapper tables.
	243	---------------------------------------------------------------/
	244
	245	/*
	246	* First create an empty table.
	247	*/
aeb5d727	248	int dm_table_create(struct dm_table **result, fmode_t mode,
17b2f66f AK	249	unsigned num_targets, struct mapped_device *md);
	250
	251	/*
	252	* Then call this once for each target.
	253	*/
	254	int dm_table_add_target(struct dm_table t, const char type,
	255	sector_t start, sector_t len, char *params);
	256
	257	/*
	258	* Finally call this to make the table ready for use.
	259	*/
	260	int dm_table_complete(struct dm_table *t);
	261
ea0ec640 MP	262	/*
	263	* Unplug all devices in a table.
	264	*/
	265	void dm_table_unplug_all(struct dm_table *t);
	266
17b2f66f AK	267	/*
	268	* Table reference counting.
	269	*/
	270	struct dm_table dm_get_table(struct mapped_device md);
	271	void dm_table_get(struct dm_table *t);
	272	void dm_table_put(struct dm_table *t);
	273
	274	/*
	275	* Queries
	276	*/
	277	sector_t dm_table_get_size(struct dm_table *t);
	278	unsigned int dm_table_get_num_targets(struct dm_table *t);
aeb5d727	279	fmode_t dm_table_get_mode(struct dm_table *t);
17b2f66f AK	280	struct mapped_device dm_table_get_md(struct dm_table t);
	281
	282	/*
	283	* Trigger an event.
	284	*/
	285	void dm_table_event(struct dm_table *t);
	286
	287	/*
	288	* The device must be suspended before calling this method.
	289	*/
	290	int dm_swap_table(struct mapped_device md, struct dm_table t);
	291
54160904 MP	292	/*
	293	* A wrapper around vmalloc.
	294	*/
	295	void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size);
	296
0da336e5 AK	297	/*-----------------------------------------------------------------
	298	* Macros.
	299	---------------------------------------------------------------/
	300	#define DM_NAME "device-mapper"
	301
10d3bd09 MP	302	#define DMCRIT(f, arg...) \
	303	printk(KERN_CRIT DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
	304
0da336e5 AK	305	#define DMERR(f, arg...) \
	306	printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
	307	#define DMERR_LIMIT(f, arg...) \
	308	do { \
	309	if (printk_ratelimit()) \
	310	printk(KERN_ERR DM_NAME ": " DM_MSG_PREFIX ": " \
	311	f "\n", ## arg); \
	312	} while (0)
	313
	314	#define DMWARN(f, arg...) \
	315	printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
	316	#define DMWARN_LIMIT(f, arg...) \
	317	do { \
	318	if (printk_ratelimit()) \
	319	printk(KERN_WARNING DM_NAME ": " DM_MSG_PREFIX ": " \
	320	f "\n", ## arg); \
	321	} while (0)
	322
	323	#define DMINFO(f, arg...) \
	324	printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f "\n", ## arg)
	325	#define DMINFO_LIMIT(f, arg...) \
	326	do { \
	327	if (printk_ratelimit()) \
	328	printk(KERN_INFO DM_NAME ": " DM_MSG_PREFIX ": " f \
	329	"\n", ## arg); \
	330	} while (0)
	331
	332	#ifdef CONFIG_DM_DEBUG
	333	# define DMDEBUG(f, arg...) \
	334	printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX " DEBUG: " f "\n", ## arg)
	335	# define DMDEBUG_LIMIT(f, arg...) \
	336	do { \
	337	if (printk_ratelimit()) \
	338	printk(KERN_DEBUG DM_NAME ": " DM_MSG_PREFIX ": " f \
	339	"\n", ## arg); \
	340	} while (0)
	341	#else
	342	# define DMDEBUG(f, arg...) do {} while (0)
	343	# define DMDEBUG_LIMIT(f, arg...) do {} while (0)
	344	#endif
	345
	346	#define DMEMIT(x...) sz += ((sz >= maxlen) ? \
	347	0 : scnprintf(result + sz, maxlen - sz, x))
	348
	349	#define SECTOR_SHIFT 9
	350
	351	/*
	352	* Definitions of return values from target end_io function.
	353	*/
	354	#define DM_ENDIO_INCOMPLETE 1
	355	#define DM_ENDIO_REQUEUE 2
	356
	357	/*
	358	* Definitions of return values from target map function.
	359	*/
	360	#define DM_MAPIO_SUBMITTED 0
	361	#define DM_MAPIO_REMAPPED 1
	362	#define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE
	363
	364	/*
	365	* Ceiling(n / sz)
	366	*/
	367	#define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz))
	368
369	#define dm_sector_div_up(n, sz) ( \
370	{ \
371	sector_t _r = ((n) + (sz) - 1); \
372	sector_div(_r, (sz)); \
373	_r; \
374	} \
375	)
376
377	/*
378	* ceiling(n / size) * size
379	*/
380	#define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))
381
d63a5ce3 MP	382	#define dm_array_too_big(fixed, obj, num) \
	383	((num) > (UINT_MAX - (fixed)) / (obj))
	384
0da336e5 AK	385	static inline sector_t to_sector(unsigned long n)
	386	{
	387	return (n >> SECTOR_SHIFT);
	388	}
	389
	390	static inline unsigned long to_bytes(sector_t n)
	391	{
	392	return (n << SECTOR_SHIFT);
	393	}
	394
17b2f66f	395	#endif /* _LINUX_DEVICE_MAPPER_H */