1 /*
2  * Copyright (C) 2001 Sistina Software (UK) Limited.
3  * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
4  *
5  * This file is released under the LGPL.
6  */
7 
8 #ifndef _LINUX_DEVICE_MAPPER_H
9 #define _LINUX_DEVICE_MAPPER_H
10 
11 #include <linux/bio.h>
12 #include <linux/blkdev.h>
13 #include <linux/dm-ioctl.h>
14 #include <linux/math64.h>
15 #include <linux/ratelimit.h>
16 
17 struct dm_dev;
18 struct dm_target;
19 struct dm_table;
20 struct dm_report_zones_args;
21 struct mapped_device;
22 struct bio_vec;
23 enum dax_access_mode;
24 
25 /*
26  * Type of table, mapped_device's mempool and request_queue
27  */
28 enum dm_queue_mode {
29 	DM_TYPE_NONE		 = 0,
30 	DM_TYPE_BIO_BASED	 = 1,
31 	DM_TYPE_REQUEST_BASED	 = 2,
32 	DM_TYPE_DAX_BIO_BASED	 = 3,
33 };
34 
35 typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE, STATUSTYPE_IMA } status_type_t;
36 
37 union map_info {
38 	void *ptr;
39 };
40 
41 /*
42  * In the constructor the target parameter will already have the
43  * table, type, begin and len fields filled in.
44  */
45 typedef int (*dm_ctr_fn) (struct dm_target *target,
46 			  unsigned int argc, char **argv);
47 
48 /*
49  * The destructor doesn't need to free the dm_target, just
50  * anything hidden ti->private.
51  */
52 typedef void (*dm_dtr_fn) (struct dm_target *ti);
53 
54 /*
55  * The map function must return:
56  * < 0: error
57  * = 0: The target will handle the io by resubmitting it later
58  * = 1: simple remap complete
59  * = 2: The target wants to push back the io
60  */
61 typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio);
62 typedef int (*dm_clone_and_map_request_fn) (struct dm_target *ti,
63 					    struct request *rq,
64 					    union map_info *map_context,
65 					    struct request **clone);
66 typedef void (*dm_release_clone_request_fn) (struct request *clone,
67 					     union map_info *map_context);
68 
69 /*
70  * Returns:
71  * < 0 : error (currently ignored)
72  * 0   : ended successfully
73  * 1   : for some reason the io has still not completed (eg,
74  *       multipath target might want to requeue a failed io).
75  * 2   : The target wants to push back the io
76  */
77 typedef int (*dm_endio_fn) (struct dm_target *ti,
78 			    struct bio *bio, blk_status_t *error);
79 typedef int (*dm_request_endio_fn) (struct dm_target *ti,
80 				    struct request *clone, blk_status_t error,
81 				    union map_info *map_context);
82 
83 typedef void (*dm_presuspend_fn) (struct dm_target *ti);
84 typedef void (*dm_presuspend_undo_fn) (struct dm_target *ti);
85 typedef void (*dm_postsuspend_fn) (struct dm_target *ti);
86 typedef int (*dm_preresume_fn) (struct dm_target *ti);
87 typedef void (*dm_resume_fn) (struct dm_target *ti);
88 
89 typedef void (*dm_status_fn) (struct dm_target *ti, status_type_t status_type,
90 			      unsigned status_flags, char *result, unsigned maxlen);
91 
92 typedef int (*dm_message_fn) (struct dm_target *ti, unsigned argc, char **argv,
93 			      char *result, unsigned maxlen);
94 
95 typedef int (*dm_prepare_ioctl_fn) (struct dm_target *ti, struct block_device **bdev);
96 
97 #ifdef CONFIG_BLK_DEV_ZONED
98 typedef int (*dm_report_zones_fn) (struct dm_target *ti,
99 				   struct dm_report_zones_args *args,
100 				   unsigned int nr_zones);
101 #else
102 /*
103  * Define dm_report_zones_fn so that targets can assign to NULL if
104  * CONFIG_BLK_DEV_ZONED disabled. Otherwise each target needs to do
105  * awkward #ifdefs in their target_type, etc.
106  */
107 typedef int (*dm_report_zones_fn) (struct dm_target *dummy);
108 #endif
109 
110 /*
111  * These iteration functions are typically used to check (and combine)
112  * properties of underlying devices.
113  * E.g. Does at least one underlying device support flush?
114  *      Does any underlying device not support WRITE_SAME?
115  *
116  * The callout function is called once for each contiguous section of
117  * an underlying device.  State can be maintained in *data.
118  * Return non-zero to stop iterating through any further devices.
119  */
120 typedef int (*iterate_devices_callout_fn) (struct dm_target *ti,
121 					   struct dm_dev *dev,
122 					   sector_t start, sector_t len,
123 					   void *data);
124 
125 /*
126  * This function must iterate through each section of device used by the
127  * target until it encounters a non-zero return code, which it then returns.
128  * Returns zero if no callout returned non-zero.
129  */
130 typedef int (*dm_iterate_devices_fn) (struct dm_target *ti,
131 				      iterate_devices_callout_fn fn,
132 				      void *data);
133 
134 typedef void (*dm_io_hints_fn) (struct dm_target *ti,
135 				struct queue_limits *limits);
136 
137 /*
138  * Returns:
139  *    0: The target can handle the next I/O immediately.
140  *    1: The target can't handle the next I/O immediately.
141  */
142 typedef int (*dm_busy_fn) (struct dm_target *ti);
143 
144 /*
145  * Returns:
146  *  < 0 : error
147  * >= 0 : the number of bytes accessible at the address
148  */
149 typedef long (*dm_dax_direct_access_fn) (struct dm_target *ti, pgoff_t pgoff,
150 		long nr_pages, enum dax_access_mode node, void **kaddr,
151 		pfn_t *pfn);
152 typedef int (*dm_dax_zero_page_range_fn)(struct dm_target *ti, pgoff_t pgoff,
153 		size_t nr_pages);
154 
155 /*
156  * Returns:
157  * != 0 : number of bytes transferred
158  * 0    : recovery write failed
159  */
160 typedef size_t (*dm_dax_recovery_write_fn)(struct dm_target *ti, pgoff_t pgoff,
161 		void *addr, size_t bytes, struct iov_iter *i);
162 
163 void dm_error(const char *message);
164 
165 struct dm_dev {
166 	struct block_device *bdev;
167 	struct dax_device *dax_dev;
168 	fmode_t mode;
169 	char name[16];
170 };
171 
172 dev_t dm_get_dev_t(const char *path);
173 
174 /*
175  * Constructors should call these functions to ensure destination devices
176  * are opened/closed correctly.
177  */
178 int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode,
179 		  struct dm_dev **result);
180 void dm_put_device(struct dm_target *ti, struct dm_dev *d);
181 
182 /*
183  * Information about a target type
184  */
185 
186 struct target_type {
187 	uint64_t features;
188 	const char *name;
189 	struct module *module;
190 	unsigned version[3];
191 	dm_ctr_fn ctr;
192 	dm_dtr_fn dtr;
193 	dm_map_fn map;
194 	dm_clone_and_map_request_fn clone_and_map_rq;
195 	dm_release_clone_request_fn release_clone_rq;
196 	dm_endio_fn end_io;
197 	dm_request_endio_fn rq_end_io;
198 	dm_presuspend_fn presuspend;
199 	dm_presuspend_undo_fn presuspend_undo;
200 	dm_postsuspend_fn postsuspend;
201 	dm_preresume_fn preresume;
202 	dm_resume_fn resume;
203 	dm_status_fn status;
204 	dm_message_fn message;
205 	dm_prepare_ioctl_fn prepare_ioctl;
206 	dm_report_zones_fn report_zones;
207 	dm_busy_fn busy;
208 	dm_iterate_devices_fn iterate_devices;
209 	dm_io_hints_fn io_hints;
210 	dm_dax_direct_access_fn direct_access;
211 	dm_dax_zero_page_range_fn dax_zero_page_range;
212 	dm_dax_recovery_write_fn dax_recovery_write;
213 
214 	/* For internal device-mapper use. */
215 	struct list_head list;
216 };
217 
218 /*
219  * Target features
220  */
221 
222 /*
223  * Any table that contains an instance of this target must have only one.
224  */
225 #define DM_TARGET_SINGLETON		0x00000001
226 #define dm_target_needs_singleton(type)	((type)->features & DM_TARGET_SINGLETON)
227 
228 /*
229  * Indicates that a target does not support read-only devices.
230  */
231 #define DM_TARGET_ALWAYS_WRITEABLE	0x00000002
232 #define dm_target_always_writeable(type) \
233 		((type)->features & DM_TARGET_ALWAYS_WRITEABLE)
234 
235 /*
236  * Any device that contains a table with an instance of this target may never
237  * have tables containing any different target type.
238  */
239 #define DM_TARGET_IMMUTABLE		0x00000004
240 #define dm_target_is_immutable(type)	((type)->features & DM_TARGET_IMMUTABLE)
241 
242 /*
243  * Indicates that a target may replace any target; even immutable targets.
244  * .map, .map_rq, .clone_and_map_rq and .release_clone_rq are all defined.
245  */
246 #define DM_TARGET_WILDCARD		0x00000008
247 #define dm_target_is_wildcard(type)	((type)->features & DM_TARGET_WILDCARD)
248 
249 /*
250  * A target implements own bio data integrity.
251  */
252 #define DM_TARGET_INTEGRITY		0x00000010
253 #define dm_target_has_integrity(type)	((type)->features & DM_TARGET_INTEGRITY)
254 
255 /*
256  * A target passes integrity data to the lower device.
257  */
258 #define DM_TARGET_PASSES_INTEGRITY	0x00000020
259 #define dm_target_passes_integrity(type) ((type)->features & DM_TARGET_PASSES_INTEGRITY)
260 
261 /*
262  * Indicates support for zoned block devices:
263  * - DM_TARGET_ZONED_HM: the target also supports host-managed zoned
264  *   block devices but does not support combining different zoned models.
265  * - DM_TARGET_MIXED_ZONED_MODEL: the target supports combining multiple
266  *   devices with different zoned models.
267  */
268 #ifdef CONFIG_BLK_DEV_ZONED
269 #define DM_TARGET_ZONED_HM		0x00000040
270 #define dm_target_supports_zoned_hm(type) ((type)->features & DM_TARGET_ZONED_HM)
271 #else
272 #define DM_TARGET_ZONED_HM		0x00000000
273 #define dm_target_supports_zoned_hm(type) (false)
274 #endif
275 
276 /*
277  * A target handles REQ_NOWAIT
278  */
279 #define DM_TARGET_NOWAIT		0x00000080
280 #define dm_target_supports_nowait(type) ((type)->features & DM_TARGET_NOWAIT)
281 
282 /*
283  * A target supports passing through inline crypto support.
284  */
285 #define DM_TARGET_PASSES_CRYPTO		0x00000100
286 #define dm_target_passes_crypto(type) ((type)->features & DM_TARGET_PASSES_CRYPTO)
287 
288 #ifdef CONFIG_BLK_DEV_ZONED
289 #define DM_TARGET_MIXED_ZONED_MODEL	0x00000200
290 #define dm_target_supports_mixed_zoned_model(type) \
291 	((type)->features & DM_TARGET_MIXED_ZONED_MODEL)
292 #else
293 #define DM_TARGET_MIXED_ZONED_MODEL	0x00000000
294 #define dm_target_supports_mixed_zoned_model(type) (false)
295 #endif
296 
297 struct dm_target {
298 	struct dm_table *table;
299 	struct target_type *type;
300 
301 	/* target limits */
302 	sector_t begin;
303 	sector_t len;
304 
305 	/* If non-zero, maximum size of I/O submitted to a target. */
306 	uint32_t max_io_len;
307 
308 	/*
309 	 * A number of zero-length barrier bios that will be submitted
310 	 * to the target for the purpose of flushing cache.
311 	 *
312 	 * The bio number can be accessed with dm_bio_get_target_bio_nr.
313 	 * It is a responsibility of the target driver to remap these bios
314 	 * to the real underlying devices.
315 	 */
316 	unsigned num_flush_bios;
317 
318 	/*
319 	 * The number of discard bios that will be submitted to the target.
320 	 * The bio number can be accessed with dm_bio_get_target_bio_nr.
321 	 */
322 	unsigned num_discard_bios;
323 
324 	/*
325 	 * The number of secure erase bios that will be submitted to the target.
326 	 * The bio number can be accessed with dm_bio_get_target_bio_nr.
327 	 */
328 	unsigned num_secure_erase_bios;
329 
330 	/*
331 	 * The number of WRITE ZEROES bios that will be submitted to the target.
332 	 * The bio number can be accessed with dm_bio_get_target_bio_nr.
333 	 */
334 	unsigned num_write_zeroes_bios;
335 
336 	/*
337 	 * The minimum number of extra bytes allocated in each io for the
338 	 * target to use.
339 	 */
340 	unsigned per_io_data_size;
341 
342 	/* target specific data */
343 	void *private;
344 
345 	/* Used to provide an error string from the ctr */
346 	char *error;
347 
348 	/*
349 	 * Set if this target needs to receive flushes regardless of
350 	 * whether or not its underlying devices have support.
351 	 */
352 	bool flush_supported:1;
353 
354 	/*
355 	 * Set if this target needs to receive discards regardless of
356 	 * whether or not its underlying devices have support.
357 	 */
358 	bool discards_supported:1;
359 
360 	/*
361 	 * Set if we need to limit the number of in-flight bios when swapping.
362 	 */
363 	bool limit_swap_bios:1;
364 
365 	/*
366 	 * Set if this target implements a zoned device and needs emulation of
367 	 * zone append operations using regular writes.
368 	 */
369 	bool emulate_zone_append:1;
370 
371 	/*
372 	 * Set if the target will submit IO using dm_submit_bio_remap()
373 	 * after returning DM_MAPIO_SUBMITTED from its map function.
374 	 */
375 	bool accounts_remapped_io:1;
376 
377 	/*
378 	 * Set if the target will submit the DM bio without first calling
379 	 * bio_set_dev(). NOTE: ideally a target should _not_ need this.
380 	 */
381 	bool needs_bio_set_dev:1;
382 };
383 
384 void *dm_per_bio_data(struct bio *bio, size_t data_size);
385 struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size);
386 unsigned dm_bio_get_target_bio_nr(const struct bio *bio);
387 
388 u64 dm_start_time_ns_from_clone(struct bio *bio);
389 
390 int dm_register_target(struct target_type *t);
391 void dm_unregister_target(struct target_type *t);
392 
393 /*
394  * Target argument parsing.
395  */
396 struct dm_arg_set {
397 	unsigned argc;
398 	char **argv;
399 };
400 
401 /*
402  * The minimum and maximum value of a numeric argument, together with
403  * the error message to use if the number is found to be outside that range.
404  */
405 struct dm_arg {
406 	unsigned min;
407 	unsigned max;
408 	char *error;
409 };
410 
411 /*
412  * Validate the next argument, either returning it as *value or, if invalid,
413  * returning -EINVAL and setting *error.
414  */
415 int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set,
416 		unsigned *value, char **error);
417 
418 /*
419  * Process the next argument as the start of a group containing between
420  * arg->min and arg->max further arguments. Either return the size as
421  * *num_args or, if invalid, return -EINVAL and set *error.
422  */
423 int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set,
424 		      unsigned *num_args, char **error);
425 
426 /*
427  * Return the current argument and shift to the next.
428  */
429 const char *dm_shift_arg(struct dm_arg_set *as);
430 
431 /*
432  * Move through num_args arguments.
433  */
434 void dm_consume_args(struct dm_arg_set *as, unsigned num_args);
435 
436 /*-----------------------------------------------------------------
437  * Functions for creating and manipulating mapped devices.
438  * Drop the reference with dm_put when you finish with the object.
439  *---------------------------------------------------------------*/
440 
441 /*
442  * DM_ANY_MINOR chooses the next available minor number.
443  */
444 #define DM_ANY_MINOR (-1)
445 int dm_create(int minor, struct mapped_device **md);
446 
447 /*
448  * Reference counting for md.
449  */
450 struct mapped_device *dm_get_md(dev_t dev);
451 void dm_get(struct mapped_device *md);
452 int dm_hold(struct mapped_device *md);
453 void dm_put(struct mapped_device *md);
454 
455 /*
456  * An arbitrary pointer may be stored alongside a mapped device.
457  */
458 void dm_set_mdptr(struct mapped_device *md, void *ptr);
459 void *dm_get_mdptr(struct mapped_device *md);
460 
461 /*
462  * A device can still be used while suspended, but I/O is deferred.
463  */
464 int dm_suspend(struct mapped_device *md, unsigned suspend_flags);
465 int dm_resume(struct mapped_device *md);
466 
467 /*
468  * Event functions.
469  */
470 uint32_t dm_get_event_nr(struct mapped_device *md);
471 int dm_wait_event(struct mapped_device *md, int event_nr);
472 uint32_t dm_next_uevent_seq(struct mapped_device *md);
473 void dm_uevent_add(struct mapped_device *md, struct list_head *elist);
474 
475 /*
476  * Info functions.
477  */
478 const char *dm_device_name(struct mapped_device *md);
479 int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid);
480 struct gendisk *dm_disk(struct mapped_device *md);
481 int dm_suspended(struct dm_target *ti);
482 int dm_post_suspending(struct dm_target *ti);
483 int dm_noflush_suspending(struct dm_target *ti);
484 void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors);
485 void dm_submit_bio_remap(struct bio *clone, struct bio *tgt_clone);
486 union map_info *dm_get_rq_mapinfo(struct request *rq);
487 
488 #ifdef CONFIG_BLK_DEV_ZONED
489 struct dm_report_zones_args {
490 	struct dm_target *tgt;
491 	sector_t next_sector;
492 
493 	void *orig_data;
494 	report_zones_cb orig_cb;
495 	unsigned int zone_idx;
496 
497 	/* must be filled by ->report_zones before calling dm_report_zones_cb */
498 	sector_t start;
499 };
500 int dm_report_zones(struct block_device *bdev, sector_t start, sector_t sector,
501 		    struct dm_report_zones_args *args, unsigned int nr_zones);
502 #endif /* CONFIG_BLK_DEV_ZONED */
503 
504 /*
505  * Device mapper functions to parse and create devices specified by the
506  * parameter "dm-mod.create="
507  */
508 int __init dm_early_create(struct dm_ioctl *dmi,
509 			   struct dm_target_spec **spec_array,
510 			   char **target_params_array);
511 
512 struct queue_limits *dm_get_queue_limits(struct mapped_device *md);
513 
514 /*
515  * Geometry functions.
516  */
517 int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo);
518 int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo);
519 
520 /*-----------------------------------------------------------------
521  * Functions for manipulating device-mapper tables.
522  *---------------------------------------------------------------*/
523 
524 /*
525  * First create an empty table.
526  */
527 int dm_table_create(struct dm_table **result, fmode_t mode,
528 		    unsigned num_targets, struct mapped_device *md);
529 
530 /*
531  * Then call this once for each target.
532  */
533 int dm_table_add_target(struct dm_table *t, const char *type,
534 			sector_t start, sector_t len, char *params);
535 
536 /*
537  * Target can use this to set the table's type.
538  * Can only ever be called from a target's ctr.
539  * Useful for "hybrid" target (supports both bio-based
540  * and request-based).
541  */
542 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type);
543 
544 /*
545  * Finally call this to make the table ready for use.
546  */
547 int dm_table_complete(struct dm_table *t);
548 
549 /*
550  * Destroy the table when finished.
551  */
552 void dm_table_destroy(struct dm_table *t);
553 
554 /*
555  * Target may require that it is never sent I/O larger than len.
556  */
557 int __must_check dm_set_target_max_io_len(struct dm_target *ti, sector_t len);
558 
559 /*
560  * Table reference counting.
561  */
562 struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx);
563 void dm_put_live_table(struct mapped_device *md, int srcu_idx);
564 void dm_sync_table(struct mapped_device *md);
565 
566 /*
567  * Queries
568  */
569 sector_t dm_table_get_size(struct dm_table *t);
570 unsigned int dm_table_get_num_targets(struct dm_table *t);
571 fmode_t dm_table_get_mode(struct dm_table *t);
572 struct mapped_device *dm_table_get_md(struct dm_table *t);
573 const char *dm_table_device_name(struct dm_table *t);
574 
575 /*
576  * Trigger an event.
577  */
578 void dm_table_event(struct dm_table *t);
579 
580 /*
581  * Run the queue for request-based targets.
582  */
583 void dm_table_run_md_queue_async(struct dm_table *t);
584 
585 /*
586  * The device must be suspended before calling this method.
587  * Returns the previous table, which the caller must destroy.
588  */
589 struct dm_table *dm_swap_table(struct mapped_device *md,
590 			       struct dm_table *t);
591 
592 /*
593  * Table blk_crypto_profile functions
594  */
595 void dm_destroy_crypto_profile(struct blk_crypto_profile *profile);
596 
597 /*-----------------------------------------------------------------
598  * Macros.
599  *---------------------------------------------------------------*/
600 #define DM_NAME "device-mapper"
601 
602 #define DM_FMT(fmt) DM_NAME ": " DM_MSG_PREFIX ": " fmt "\n"
603 
604 #define DMCRIT(fmt, ...) pr_crit(DM_FMT(fmt), ##__VA_ARGS__)
605 
606 #define DMERR(fmt, ...) pr_err(DM_FMT(fmt), ##__VA_ARGS__)
607 #define DMERR_LIMIT(fmt, ...) pr_err_ratelimited(DM_FMT(fmt), ##__VA_ARGS__)
608 #define DMWARN(fmt, ...) pr_warn(DM_FMT(fmt), ##__VA_ARGS__)
609 #define DMWARN_LIMIT(fmt, ...) pr_warn_ratelimited(DM_FMT(fmt), ##__VA_ARGS__)
610 #define DMINFO(fmt, ...) pr_info(DM_FMT(fmt), ##__VA_ARGS__)
611 #define DMINFO_LIMIT(fmt, ...) pr_info_ratelimited(DM_FMT(fmt), ##__VA_ARGS__)
612 
613 #define DMDEBUG(fmt, ...) pr_debug(DM_FMT(fmt), ##__VA_ARGS__)
614 #define DMDEBUG_LIMIT(fmt, ...) pr_debug_ratelimited(DM_FMT(fmt), ##__VA_ARGS__)
615 
616 #define DMEMIT(x...) sz += ((sz >= maxlen) ? \
617 			  0 : scnprintf(result + sz, maxlen - sz, x))
618 
619 #define DMEMIT_TARGET_NAME_VERSION(y) \
620 		DMEMIT("target_name=%s,target_version=%u.%u.%u", \
621 		       (y)->name, (y)->version[0], (y)->version[1], (y)->version[2])
622 
623 /*
624  * Definitions of return values from target end_io function.
625  */
626 #define DM_ENDIO_DONE		0
627 #define DM_ENDIO_INCOMPLETE	1
628 #define DM_ENDIO_REQUEUE	2
629 #define DM_ENDIO_DELAY_REQUEUE	3
630 
631 /*
632  * Definitions of return values from target map function.
633  */
634 #define DM_MAPIO_SUBMITTED	0
635 #define DM_MAPIO_REMAPPED	1
636 #define DM_MAPIO_REQUEUE	DM_ENDIO_REQUEUE
637 #define DM_MAPIO_DELAY_REQUEUE	DM_ENDIO_DELAY_REQUEUE
638 #define DM_MAPIO_KILL		4
639 
640 #define dm_sector_div64(x, y)( \
641 { \
642 	u64 _res; \
643 	(x) = div64_u64_rem(x, y, &_res); \
644 	_res; \
645 } \
646 )
647 
648 /*
649  * Ceiling(n / sz)
650  */
651 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz))
652 
653 #define dm_sector_div_up(n, sz) ( \
654 { \
655 	sector_t _r = ((n) + (sz) - 1); \
656 	sector_div(_r, (sz)); \
657 	_r; \
658 } \
659 )
660 
661 /*
662  * ceiling(n / size) * size
663  */
664 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz))
665 
666 /*
667  * Sector offset taken relative to the start of the target instead of
668  * relative to the start of the device.
669  */
670 #define dm_target_offset(ti, sector) ((sector) - (ti)->begin)
671 
to_sector(unsigned long long n)672 static inline sector_t to_sector(unsigned long long n)
673 {
674 	return (n >> SECTOR_SHIFT);
675 }
676 
to_bytes(sector_t n)677 static inline unsigned long to_bytes(sector_t n)
678 {
679 	return (n << SECTOR_SHIFT);
680 }
681 
682 #endif	/* _LINUX_DEVICE_MAPPER_H */
683