1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2001 Sistina Software (UK) Limited. 4 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. 5 * 6 * This file is released under the LGPL. 7 */ 8 9 #ifndef _LINUX_DEVICE_MAPPER_H 10 #define _LINUX_DEVICE_MAPPER_H 11 12 #include <linux/bio.h> 13 #include <linux/blkdev.h> 14 #include <linux/dm-ioctl.h> 15 #include <linux/math64.h> 16 #include <linux/ratelimit.h> 17 18 struct dm_dev; 19 struct dm_target; 20 struct dm_table; 21 struct dm_report_zones_args; 22 struct mapped_device; 23 struct bio_vec; 24 enum dax_access_mode; 25 26 /* 27 * Type of table, mapped_device's mempool and request_queue 28 */ 29 enum dm_queue_mode { 30 DM_TYPE_NONE = 0, 31 DM_TYPE_BIO_BASED = 1, 32 DM_TYPE_REQUEST_BASED = 2, 33 DM_TYPE_DAX_BIO_BASED = 3, 34 }; 35 36 typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE, STATUSTYPE_IMA } status_type_t; 37 38 union map_info { 39 void *ptr; 40 }; 41 42 /* 43 * In the constructor the target parameter will already have the 44 * table, type, begin and len fields filled in. 45 */ 46 typedef int (*dm_ctr_fn) (struct dm_target *target, 47 unsigned int argc, char **argv); 48 49 /* 50 * The destructor doesn't need to free the dm_target, just 51 * anything hidden ti->private. 52 */ 53 typedef void (*dm_dtr_fn) (struct dm_target *ti); 54 55 /* 56 * The map function must return: 57 * < 0: error 58 * = 0: The target will handle the io by resubmitting it later 59 * = 1: simple remap complete 60 * = 2: The target wants to push back the io 61 */ 62 typedef int (*dm_map_fn) (struct dm_target *ti, struct bio *bio); 63 typedef int (*dm_clone_and_map_request_fn) (struct dm_target *ti, 64 struct request *rq, 65 union map_info *map_context, 66 struct request **clone); 67 typedef void (*dm_release_clone_request_fn) (struct request *clone, 68 union map_info *map_context); 69 70 /* 71 * Returns: 72 * < 0 : error (currently ignored) 73 * 0 : ended successfully 74 * 1 : for some reason the io has still not completed (eg, 75 * multipath target might want to requeue a failed io). 76 * 2 : The target wants to push back the io 77 */ 78 typedef int (*dm_endio_fn) (struct dm_target *ti, 79 struct bio *bio, blk_status_t *error); 80 typedef int (*dm_request_endio_fn) (struct dm_target *ti, 81 struct request *clone, blk_status_t error, 82 union map_info *map_context); 83 84 typedef void (*dm_presuspend_fn) (struct dm_target *ti); 85 typedef void (*dm_presuspend_undo_fn) (struct dm_target *ti); 86 typedef void (*dm_postsuspend_fn) (struct dm_target *ti); 87 typedef int (*dm_preresume_fn) (struct dm_target *ti); 88 typedef void (*dm_resume_fn) (struct dm_target *ti); 89 90 typedef void (*dm_status_fn) (struct dm_target *ti, status_type_t status_type, 91 unsigned int status_flags, char *result, unsigned int maxlen); 92 93 typedef int (*dm_message_fn) (struct dm_target *ti, unsigned int argc, char **argv, 94 char *result, unsigned int maxlen); 95 96 typedef int (*dm_prepare_ioctl_fn) (struct dm_target *ti, struct block_device **bdev); 97 98 #ifdef CONFIG_BLK_DEV_ZONED 99 typedef int (*dm_report_zones_fn) (struct dm_target *ti, 100 struct dm_report_zones_args *args, 101 unsigned int nr_zones); 102 #else 103 /* 104 * Define dm_report_zones_fn so that targets can assign to NULL if 105 * CONFIG_BLK_DEV_ZONED disabled. Otherwise each target needs to do 106 * awkward #ifdefs in their target_type, etc. 107 */ 108 typedef int (*dm_report_zones_fn) (struct dm_target *dummy); 109 #endif 110 111 /* 112 * These iteration functions are typically used to check (and combine) 113 * properties of underlying devices. 114 * E.g. Does at least one underlying device support flush? 115 * Does any underlying device not support WRITE_SAME? 116 * 117 * The callout function is called once for each contiguous section of 118 * an underlying device. State can be maintained in *data. 119 * Return non-zero to stop iterating through any further devices. 120 */ 121 typedef int (*iterate_devices_callout_fn) (struct dm_target *ti, 122 struct dm_dev *dev, 123 sector_t start, sector_t len, 124 void *data); 125 126 /* 127 * This function must iterate through each section of device used by the 128 * target until it encounters a non-zero return code, which it then returns. 129 * Returns zero if no callout returned non-zero. 130 */ 131 typedef int (*dm_iterate_devices_fn) (struct dm_target *ti, 132 iterate_devices_callout_fn fn, 133 void *data); 134 135 typedef void (*dm_io_hints_fn) (struct dm_target *ti, 136 struct queue_limits *limits); 137 138 /* 139 * Returns: 140 * 0: The target can handle the next I/O immediately. 141 * 1: The target can't handle the next I/O immediately. 142 */ 143 typedef int (*dm_busy_fn) (struct dm_target *ti); 144 145 /* 146 * Returns: 147 * < 0 : error 148 * >= 0 : the number of bytes accessible at the address 149 */ 150 typedef long (*dm_dax_direct_access_fn) (struct dm_target *ti, pgoff_t pgoff, 151 long nr_pages, enum dax_access_mode node, void **kaddr, 152 pfn_t *pfn); 153 typedef int (*dm_dax_zero_page_range_fn)(struct dm_target *ti, pgoff_t pgoff, 154 size_t nr_pages); 155 156 /* 157 * Returns: 158 * != 0 : number of bytes transferred 159 * 0 : recovery write failed 160 */ 161 typedef size_t (*dm_dax_recovery_write_fn)(struct dm_target *ti, pgoff_t pgoff, 162 void *addr, size_t bytes, struct iov_iter *i); 163 164 void dm_error(const char *message); 165 166 struct dm_dev { 167 struct block_device *bdev; 168 struct dax_device *dax_dev; 169 blk_mode_t mode; 170 char name[16]; 171 }; 172 173 /* 174 * Constructors should call these functions to ensure destination devices 175 * are opened/closed correctly. 176 */ 177 int dm_get_device(struct dm_target *ti, const char *path, blk_mode_t mode, 178 struct dm_dev **result); 179 void dm_put_device(struct dm_target *ti, struct dm_dev *d); 180 181 /* 182 * Information about a target type 183 */ 184 185 struct target_type { 186 uint64_t features; 187 const char *name; 188 struct module *module; 189 unsigned int version[3]; 190 dm_ctr_fn ctr; 191 dm_dtr_fn dtr; 192 dm_map_fn map; 193 dm_clone_and_map_request_fn clone_and_map_rq; 194 dm_release_clone_request_fn release_clone_rq; 195 dm_endio_fn end_io; 196 dm_request_endio_fn rq_end_io; 197 dm_presuspend_fn presuspend; 198 dm_presuspend_undo_fn presuspend_undo; 199 dm_postsuspend_fn postsuspend; 200 dm_preresume_fn preresume; 201 dm_resume_fn resume; 202 dm_status_fn status; 203 dm_message_fn message; 204 dm_prepare_ioctl_fn prepare_ioctl; 205 dm_report_zones_fn report_zones; 206 dm_busy_fn busy; 207 dm_iterate_devices_fn iterate_devices; 208 dm_io_hints_fn io_hints; 209 dm_dax_direct_access_fn direct_access; 210 dm_dax_zero_page_range_fn dax_zero_page_range; 211 dm_dax_recovery_write_fn dax_recovery_write; 212 213 /* For internal device-mapper use. */ 214 struct list_head list; 215 }; 216 217 /* 218 * Target features 219 */ 220 221 /* 222 * Any table that contains an instance of this target must have only one. 223 */ 224 #define DM_TARGET_SINGLETON 0x00000001 225 #define dm_target_needs_singleton(type) ((type)->features & DM_TARGET_SINGLETON) 226 227 /* 228 * Indicates that a target does not support read-only devices. 229 */ 230 #define DM_TARGET_ALWAYS_WRITEABLE 0x00000002 231 #define dm_target_always_writeable(type) \ 232 ((type)->features & DM_TARGET_ALWAYS_WRITEABLE) 233 234 /* 235 * Any device that contains a table with an instance of this target may never 236 * have tables containing any different target type. 237 */ 238 #define DM_TARGET_IMMUTABLE 0x00000004 239 #define dm_target_is_immutable(type) ((type)->features & DM_TARGET_IMMUTABLE) 240 241 /* 242 * Indicates that a target may replace any target; even immutable targets. 243 * .map, .map_rq, .clone_and_map_rq and .release_clone_rq are all defined. 244 */ 245 #define DM_TARGET_WILDCARD 0x00000008 246 #define dm_target_is_wildcard(type) ((type)->features & DM_TARGET_WILDCARD) 247 248 /* 249 * A target implements own bio data integrity. 250 */ 251 #define DM_TARGET_INTEGRITY 0x00000010 252 #define dm_target_has_integrity(type) ((type)->features & DM_TARGET_INTEGRITY) 253 254 /* 255 * A target passes integrity data to the lower device. 256 */ 257 #define DM_TARGET_PASSES_INTEGRITY 0x00000020 258 #define dm_target_passes_integrity(type) ((type)->features & DM_TARGET_PASSES_INTEGRITY) 259 260 /* 261 * Indicates support for zoned block devices: 262 * - DM_TARGET_ZONED_HM: the target also supports host-managed zoned 263 * block devices but does not support combining different zoned models. 264 * - DM_TARGET_MIXED_ZONED_MODEL: the target supports combining multiple 265 * devices with different zoned models. 266 */ 267 #ifdef CONFIG_BLK_DEV_ZONED 268 #define DM_TARGET_ZONED_HM 0x00000040 269 #define dm_target_supports_zoned_hm(type) ((type)->features & DM_TARGET_ZONED_HM) 270 #else 271 #define DM_TARGET_ZONED_HM 0x00000000 272 #define dm_target_supports_zoned_hm(type) (false) 273 #endif 274 275 /* 276 * A target handles REQ_NOWAIT 277 */ 278 #define DM_TARGET_NOWAIT 0x00000080 279 #define dm_target_supports_nowait(type) ((type)->features & DM_TARGET_NOWAIT) 280 281 /* 282 * A target supports passing through inline crypto support. 283 */ 284 #define DM_TARGET_PASSES_CRYPTO 0x00000100 285 #define dm_target_passes_crypto(type) ((type)->features & DM_TARGET_PASSES_CRYPTO) 286 287 #ifdef CONFIG_BLK_DEV_ZONED 288 #define DM_TARGET_MIXED_ZONED_MODEL 0x00000200 289 #define dm_target_supports_mixed_zoned_model(type) \ 290 ((type)->features & DM_TARGET_MIXED_ZONED_MODEL) 291 #else 292 #define DM_TARGET_MIXED_ZONED_MODEL 0x00000000 293 #define dm_target_supports_mixed_zoned_model(type) (false) 294 #endif 295 296 struct dm_target { 297 struct dm_table *table; 298 struct target_type *type; 299 300 /* target limits */ 301 sector_t begin; 302 sector_t len; 303 304 /* If non-zero, maximum size of I/O submitted to a target. */ 305 uint32_t max_io_len; 306 307 /* 308 * A number of zero-length barrier bios that will be submitted 309 * to the target for the purpose of flushing cache. 310 * 311 * The bio number can be accessed with dm_bio_get_target_bio_nr. 312 * It is a responsibility of the target driver to remap these bios 313 * to the real underlying devices. 314 */ 315 unsigned int num_flush_bios; 316 317 /* 318 * The number of discard bios that will be submitted to the target. 319 * The bio number can be accessed with dm_bio_get_target_bio_nr. 320 */ 321 unsigned int num_discard_bios; 322 323 /* 324 * The number of secure erase bios that will be submitted to the target. 325 * The bio number can be accessed with dm_bio_get_target_bio_nr. 326 */ 327 unsigned int num_secure_erase_bios; 328 329 /* 330 * The number of WRITE ZEROES bios that will be submitted to the target. 331 * The bio number can be accessed with dm_bio_get_target_bio_nr. 332 */ 333 unsigned int num_write_zeroes_bios; 334 335 /* 336 * The minimum number of extra bytes allocated in each io for the 337 * target to use. 338 */ 339 unsigned int per_io_data_size; 340 341 /* target specific data */ 342 void *private; 343 344 /* Used to provide an error string from the ctr */ 345 char *error; 346 347 /* 348 * Set if this target needs to receive flushes regardless of 349 * whether or not its underlying devices have support. 350 */ 351 bool flush_supported:1; 352 353 /* 354 * Set if this target needs to receive discards regardless of 355 * whether or not its underlying devices have support. 356 */ 357 bool discards_supported:1; 358 359 /* 360 * Set if this target requires that discards be split on 361 * 'max_discard_sectors' boundaries. 362 */ 363 bool max_discard_granularity:1; 364 365 /* 366 * Set if this target requires that secure_erases be split on 367 * 'max_secure_erase_sectors' boundaries. 368 */ 369 bool max_secure_erase_granularity:1; 370 371 /* 372 * Set if this target requires that write_zeroes be split on 373 * 'max_write_zeroes_sectors' boundaries. 374 */ 375 bool max_write_zeroes_granularity:1; 376 377 /* 378 * Set if we need to limit the number of in-flight bios when swapping. 379 */ 380 bool limit_swap_bios:1; 381 382 /* 383 * Set if this target implements a zoned device and needs emulation of 384 * zone append operations using regular writes. 385 */ 386 bool emulate_zone_append:1; 387 388 /* 389 * Set if the target will submit IO using dm_submit_bio_remap() 390 * after returning DM_MAPIO_SUBMITTED from its map function. 391 */ 392 bool accounts_remapped_io:1; 393 394 /* 395 * Set if the target will submit the DM bio without first calling 396 * bio_set_dev(). NOTE: ideally a target should _not_ need this. 397 */ 398 bool needs_bio_set_dev:1; 399 }; 400 401 void *dm_per_bio_data(struct bio *bio, size_t data_size); 402 struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size); 403 unsigned int dm_bio_get_target_bio_nr(const struct bio *bio); 404 405 u64 dm_start_time_ns_from_clone(struct bio *bio); 406 407 int dm_register_target(struct target_type *t); 408 void dm_unregister_target(struct target_type *t); 409 410 /* 411 * Target argument parsing. 412 */ 413 struct dm_arg_set { 414 unsigned int argc; 415 char **argv; 416 }; 417 418 /* 419 * The minimum and maximum value of a numeric argument, together with 420 * the error message to use if the number is found to be outside that range. 421 */ 422 struct dm_arg { 423 unsigned int min; 424 unsigned int max; 425 char *error; 426 }; 427 428 /* 429 * Validate the next argument, either returning it as *value or, if invalid, 430 * returning -EINVAL and setting *error. 431 */ 432 int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set, 433 unsigned int *value, char **error); 434 435 /* 436 * Process the next argument as the start of a group containing between 437 * arg->min and arg->max further arguments. Either return the size as 438 * *num_args or, if invalid, return -EINVAL and set *error. 439 */ 440 int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set, 441 unsigned int *num_args, char **error); 442 443 /* 444 * Return the current argument and shift to the next. 445 */ 446 const char *dm_shift_arg(struct dm_arg_set *as); 447 448 /* 449 * Move through num_args arguments. 450 */ 451 void dm_consume_args(struct dm_arg_set *as, unsigned int num_args); 452 453 /* 454 *---------------------------------------------------------------- 455 * Functions for creating and manipulating mapped devices. 456 * Drop the reference with dm_put when you finish with the object. 457 *---------------------------------------------------------------- 458 */ 459 460 /* 461 * DM_ANY_MINOR chooses the next available minor number. 462 */ 463 #define DM_ANY_MINOR (-1) 464 int dm_create(int minor, struct mapped_device **md); 465 466 /* 467 * Reference counting for md. 468 */ 469 struct mapped_device *dm_get_md(dev_t dev); 470 void dm_get(struct mapped_device *md); 471 int dm_hold(struct mapped_device *md); 472 void dm_put(struct mapped_device *md); 473 474 /* 475 * An arbitrary pointer may be stored alongside a mapped device. 476 */ 477 void dm_set_mdptr(struct mapped_device *md, void *ptr); 478 void *dm_get_mdptr(struct mapped_device *md); 479 480 /* 481 * A device can still be used while suspended, but I/O is deferred. 482 */ 483 int dm_suspend(struct mapped_device *md, unsigned int suspend_flags); 484 int dm_resume(struct mapped_device *md); 485 486 /* 487 * Event functions. 488 */ 489 uint32_t dm_get_event_nr(struct mapped_device *md); 490 int dm_wait_event(struct mapped_device *md, int event_nr); 491 uint32_t dm_next_uevent_seq(struct mapped_device *md); 492 void dm_uevent_add(struct mapped_device *md, struct list_head *elist); 493 494 /* 495 * Info functions. 496 */ 497 const char *dm_device_name(struct mapped_device *md); 498 int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid); 499 struct gendisk *dm_disk(struct mapped_device *md); 500 int dm_suspended(struct dm_target *ti); 501 int dm_post_suspending(struct dm_target *ti); 502 int dm_noflush_suspending(struct dm_target *ti); 503 void dm_accept_partial_bio(struct bio *bio, unsigned int n_sectors); 504 void dm_submit_bio_remap(struct bio *clone, struct bio *tgt_clone); 505 union map_info *dm_get_rq_mapinfo(struct request *rq); 506 507 #ifdef CONFIG_BLK_DEV_ZONED 508 struct dm_report_zones_args { 509 struct dm_target *tgt; 510 sector_t next_sector; 511 512 void *orig_data; 513 report_zones_cb orig_cb; 514 unsigned int zone_idx; 515 516 /* must be filled by ->report_zones before calling dm_report_zones_cb */ 517 sector_t start; 518 }; 519 int dm_report_zones(struct block_device *bdev, sector_t start, sector_t sector, 520 struct dm_report_zones_args *args, unsigned int nr_zones); 521 #endif /* CONFIG_BLK_DEV_ZONED */ 522 523 /* 524 * Device mapper functions to parse and create devices specified by the 525 * parameter "dm-mod.create=" 526 */ 527 int __init dm_early_create(struct dm_ioctl *dmi, 528 struct dm_target_spec **spec_array, 529 char **target_params_array); 530 531 /* 532 * Geometry functions. 533 */ 534 int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo); 535 int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo); 536 537 /* 538 *--------------------------------------------------------------- 539 * Functions for manipulating device-mapper tables. 540 *--------------------------------------------------------------- 541 */ 542 543 /* 544 * First create an empty table. 545 */ 546 int dm_table_create(struct dm_table **result, blk_mode_t mode, 547 unsigned int num_targets, struct mapped_device *md); 548 549 /* 550 * Then call this once for each target. 551 */ 552 int dm_table_add_target(struct dm_table *t, const char *type, 553 sector_t start, sector_t len, char *params); 554 555 /* 556 * Target can use this to set the table's type. 557 * Can only ever be called from a target's ctr. 558 * Useful for "hybrid" target (supports both bio-based 559 * and request-based). 560 */ 561 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type); 562 563 /* 564 * Finally call this to make the table ready for use. 565 */ 566 int dm_table_complete(struct dm_table *t); 567 568 /* 569 * Destroy the table when finished. 570 */ 571 void dm_table_destroy(struct dm_table *t); 572 573 /* 574 * Target may require that it is never sent I/O larger than len. 575 */ 576 int __must_check dm_set_target_max_io_len(struct dm_target *ti, sector_t len); 577 578 /* 579 * Table reference counting. 580 */ 581 struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx); 582 void dm_put_live_table(struct mapped_device *md, int srcu_idx); 583 void dm_sync_table(struct mapped_device *md); 584 585 /* 586 * Queries 587 */ 588 sector_t dm_table_get_size(struct dm_table *t); 589 blk_mode_t dm_table_get_mode(struct dm_table *t); 590 struct mapped_device *dm_table_get_md(struct dm_table *t); 591 const char *dm_table_device_name(struct dm_table *t); 592 593 /* 594 * Trigger an event. 595 */ 596 void dm_table_event(struct dm_table *t); 597 598 /* 599 * Run the queue for request-based targets. 600 */ 601 void dm_table_run_md_queue_async(struct dm_table *t); 602 603 /* 604 * The device must be suspended before calling this method. 605 * Returns the previous table, which the caller must destroy. 606 */ 607 struct dm_table *dm_swap_table(struct mapped_device *md, 608 struct dm_table *t); 609 610 /* 611 * Table blk_crypto_profile functions 612 */ 613 void dm_destroy_crypto_profile(struct blk_crypto_profile *profile); 614 615 /* 616 *--------------------------------------------------------------- 617 * Macros. 618 *--------------------------------------------------------------- 619 */ 620 #define DM_NAME "device-mapper" 621 622 #define DM_FMT(fmt) DM_NAME ": " DM_MSG_PREFIX ": " fmt "\n" 623 624 #define DMCRIT(fmt, ...) pr_crit(DM_FMT(fmt), ##__VA_ARGS__) 625 626 #define DMERR(fmt, ...) pr_err(DM_FMT(fmt), ##__VA_ARGS__) 627 #define DMERR_LIMIT(fmt, ...) pr_err_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 628 #define DMWARN(fmt, ...) pr_warn(DM_FMT(fmt), ##__VA_ARGS__) 629 #define DMWARN_LIMIT(fmt, ...) pr_warn_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 630 #define DMINFO(fmt, ...) pr_info(DM_FMT(fmt), ##__VA_ARGS__) 631 #define DMINFO_LIMIT(fmt, ...) pr_info_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 632 633 #define DMDEBUG(fmt, ...) pr_debug(DM_FMT(fmt), ##__VA_ARGS__) 634 #define DMDEBUG_LIMIT(fmt, ...) pr_debug_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 635 636 #define DMEMIT(x...) (sz += ((sz >= maxlen) ? 0 : scnprintf(result + sz, maxlen - sz, x))) 637 638 #define DMEMIT_TARGET_NAME_VERSION(y) \ 639 DMEMIT("target_name=%s,target_version=%u.%u.%u", \ 640 (y)->name, (y)->version[0], (y)->version[1], (y)->version[2]) 641 642 /** 643 * module_dm() - Helper macro for DM targets that don't do anything 644 * special in their module_init and module_exit. 645 * Each module may only use this macro once, and calling it replaces 646 * module_init() and module_exit(). 647 * 648 * @name: DM target's name 649 */ 650 #define module_dm(name) \ 651 static int __init dm_##name##_init(void) \ 652 { \ 653 return dm_register_target(&(name##_target)); \ 654 } \ 655 module_init(dm_##name##_init) \ 656 static void __exit dm_##name##_exit(void) \ 657 { \ 658 dm_unregister_target(&(name##_target)); \ 659 } \ 660 module_exit(dm_##name##_exit) 661 662 /* 663 * Definitions of return values from target end_io function. 664 */ 665 #define DM_ENDIO_DONE 0 666 #define DM_ENDIO_INCOMPLETE 1 667 #define DM_ENDIO_REQUEUE 2 668 #define DM_ENDIO_DELAY_REQUEUE 3 669 670 /* 671 * Definitions of return values from target map function. 672 */ 673 #define DM_MAPIO_SUBMITTED 0 674 #define DM_MAPIO_REMAPPED 1 675 #define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE 676 #define DM_MAPIO_DELAY_REQUEUE DM_ENDIO_DELAY_REQUEUE 677 #define DM_MAPIO_KILL 4 678 679 #define dm_sector_div64(x, y)( \ 680 { \ 681 u64 _res; \ 682 (x) = div64_u64_rem(x, y, &_res); \ 683 _res; \ 684 } \ 685 ) 686 687 /* 688 * Ceiling(n / sz) 689 */ 690 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) 691 692 #define dm_sector_div_up(n, sz) ( \ 693 { \ 694 sector_t _r = ((n) + (sz) - 1); \ 695 sector_div(_r, (sz)); \ 696 _r; \ 697 } \ 698 ) 699 700 /* 701 * ceiling(n / size) * size 702 */ 703 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) 704 705 /* 706 * Sector offset taken relative to the start of the target instead of 707 * relative to the start of the device. 708 */ 709 #define dm_target_offset(ti, sector) ((sector) - (ti)->begin) 710 to_sector(unsigned long long n)711 static inline sector_t to_sector(unsigned long long n) 712 { 713 return (n >> SECTOR_SHIFT); 714 } 715 to_bytes(sector_t n)716 static inline unsigned long to_bytes(sector_t n) 717 { 718 return (n << SECTOR_SHIFT); 719 } 720 721 #endif /* _LINUX_DEVICE_MAPPER_H */ 722