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 file *bdev_file; 169 struct dax_device *dax_dev; 170 blk_mode_t mode; 171 char name[16]; 172 }; 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, blk_mode_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 int 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 int 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 int 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 int 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 int 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 int 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 this target requires that discards be split on 362 * 'max_discard_sectors' boundaries. 363 */ 364 bool max_discard_granularity:1; 365 366 /* 367 * Set if this target requires that secure_erases be split on 368 * 'max_secure_erase_sectors' boundaries. 369 */ 370 bool max_secure_erase_granularity:1; 371 372 /* 373 * Set if this target requires that write_zeroes be split on 374 * 'max_write_zeroes_sectors' boundaries. 375 */ 376 bool max_write_zeroes_granularity:1; 377 378 /* 379 * Set if we need to limit the number of in-flight bios when swapping. 380 */ 381 bool limit_swap_bios:1; 382 383 /* 384 * Set if this target implements a zoned device and needs emulation of 385 * zone append operations using regular writes. 386 */ 387 bool emulate_zone_append:1; 388 389 /* 390 * Set if the target will submit IO using dm_submit_bio_remap() 391 * after returning DM_MAPIO_SUBMITTED from its map function. 392 */ 393 bool accounts_remapped_io:1; 394 395 /* 396 * Set if the target will submit the DM bio without first calling 397 * bio_set_dev(). NOTE: ideally a target should _not_ need this. 398 */ 399 bool needs_bio_set_dev:1; 400 }; 401 402 void *dm_per_bio_data(struct bio *bio, size_t data_size); 403 struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size); 404 unsigned int dm_bio_get_target_bio_nr(const struct bio *bio); 405 406 u64 dm_start_time_ns_from_clone(struct bio *bio); 407 408 int dm_register_target(struct target_type *t); 409 void dm_unregister_target(struct target_type *t); 410 411 /* 412 * Target argument parsing. 413 */ 414 struct dm_arg_set { 415 unsigned int argc; 416 char **argv; 417 }; 418 419 /* 420 * The minimum and maximum value of a numeric argument, together with 421 * the error message to use if the number is found to be outside that range. 422 */ 423 struct dm_arg { 424 unsigned int min; 425 unsigned int max; 426 char *error; 427 }; 428 429 /* 430 * Validate the next argument, either returning it as *value or, if invalid, 431 * returning -EINVAL and setting *error. 432 */ 433 int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set, 434 unsigned int *value, char **error); 435 436 /* 437 * Process the next argument as the start of a group containing between 438 * arg->min and arg->max further arguments. Either return the size as 439 * *num_args or, if invalid, return -EINVAL and set *error. 440 */ 441 int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set, 442 unsigned int *num_args, char **error); 443 444 /* 445 * Return the current argument and shift to the next. 446 */ 447 const char *dm_shift_arg(struct dm_arg_set *as); 448 449 /* 450 * Move through num_args arguments. 451 */ 452 void dm_consume_args(struct dm_arg_set *as, unsigned int num_args); 453 454 /* 455 *---------------------------------------------------------------- 456 * Functions for creating and manipulating mapped devices. 457 * Drop the reference with dm_put when you finish with the object. 458 *---------------------------------------------------------------- 459 */ 460 461 /* 462 * DM_ANY_MINOR chooses the next available minor number. 463 */ 464 #define DM_ANY_MINOR (-1) 465 int dm_create(int minor, struct mapped_device **md); 466 467 /* 468 * Reference counting for md. 469 */ 470 struct mapped_device *dm_get_md(dev_t dev); 471 void dm_get(struct mapped_device *md); 472 int dm_hold(struct mapped_device *md); 473 void dm_put(struct mapped_device *md); 474 475 /* 476 * An arbitrary pointer may be stored alongside a mapped device. 477 */ 478 void dm_set_mdptr(struct mapped_device *md, void *ptr); 479 void *dm_get_mdptr(struct mapped_device *md); 480 481 /* 482 * A device can still be used while suspended, but I/O is deferred. 483 */ 484 int dm_suspend(struct mapped_device *md, unsigned int suspend_flags); 485 int dm_resume(struct mapped_device *md); 486 487 /* 488 * Event functions. 489 */ 490 uint32_t dm_get_event_nr(struct mapped_device *md); 491 int dm_wait_event(struct mapped_device *md, int event_nr); 492 uint32_t dm_next_uevent_seq(struct mapped_device *md); 493 void dm_uevent_add(struct mapped_device *md, struct list_head *elist); 494 495 /* 496 * Info functions. 497 */ 498 const char *dm_device_name(struct mapped_device *md); 499 int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid); 500 struct gendisk *dm_disk(struct mapped_device *md); 501 int dm_suspended(struct dm_target *ti); 502 int dm_post_suspending(struct dm_target *ti); 503 int dm_noflush_suspending(struct dm_target *ti); 504 void dm_accept_partial_bio(struct bio *bio, unsigned int n_sectors); 505 void dm_submit_bio_remap(struct bio *clone, struct bio *tgt_clone); 506 union map_info *dm_get_rq_mapinfo(struct request *rq); 507 508 #ifdef CONFIG_BLK_DEV_ZONED 509 struct dm_report_zones_args { 510 struct dm_target *tgt; 511 sector_t next_sector; 512 513 void *orig_data; 514 report_zones_cb orig_cb; 515 unsigned int zone_idx; 516 517 /* must be filled by ->report_zones before calling dm_report_zones_cb */ 518 sector_t start; 519 }; 520 int dm_report_zones(struct block_device *bdev, sector_t start, sector_t sector, 521 struct dm_report_zones_args *args, unsigned int nr_zones); 522 #endif /* CONFIG_BLK_DEV_ZONED */ 523 524 /* 525 * Device mapper functions to parse and create devices specified by the 526 * parameter "dm-mod.create=" 527 */ 528 int __init dm_early_create(struct dm_ioctl *dmi, 529 struct dm_target_spec **spec_array, 530 char **target_params_array); 531 532 /* 533 * Geometry functions. 534 */ 535 int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo); 536 int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo); 537 538 /* 539 *--------------------------------------------------------------- 540 * Functions for manipulating device-mapper tables. 541 *--------------------------------------------------------------- 542 */ 543 544 /* 545 * First create an empty table. 546 */ 547 int dm_table_create(struct dm_table **result, blk_mode_t mode, 548 unsigned int num_targets, struct mapped_device *md); 549 550 /* 551 * Then call this once for each target. 552 */ 553 int dm_table_add_target(struct dm_table *t, const char *type, 554 sector_t start, sector_t len, char *params); 555 556 /* 557 * Target can use this to set the table's type. 558 * Can only ever be called from a target's ctr. 559 * Useful for "hybrid" target (supports both bio-based 560 * and request-based). 561 */ 562 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type); 563 564 /* 565 * Finally call this to make the table ready for use. 566 */ 567 int dm_table_complete(struct dm_table *t); 568 569 /* 570 * Destroy the table when finished. 571 */ 572 void dm_table_destroy(struct dm_table *t); 573 574 /* 575 * Target may require that it is never sent I/O larger than len. 576 */ 577 int __must_check dm_set_target_max_io_len(struct dm_target *ti, sector_t len); 578 579 /* 580 * Table reference counting. 581 */ 582 struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx); 583 void dm_put_live_table(struct mapped_device *md, int srcu_idx); 584 void dm_sync_table(struct mapped_device *md); 585 586 /* 587 * Queries 588 */ 589 sector_t dm_table_get_size(struct dm_table *t); 590 blk_mode_t dm_table_get_mode(struct dm_table *t); 591 struct mapped_device *dm_table_get_md(struct dm_table *t); 592 const char *dm_table_device_name(struct dm_table *t); 593 594 /* 595 * Trigger an event. 596 */ 597 void dm_table_event(struct dm_table *t); 598 599 /* 600 * Run the queue for request-based targets. 601 */ 602 void dm_table_run_md_queue_async(struct dm_table *t); 603 604 /* 605 * The device must be suspended before calling this method. 606 * Returns the previous table, which the caller must destroy. 607 */ 608 struct dm_table *dm_swap_table(struct mapped_device *md, 609 struct dm_table *t); 610 611 /* 612 * Table blk_crypto_profile functions 613 */ 614 void dm_destroy_crypto_profile(struct blk_crypto_profile *profile); 615 616 /* 617 *--------------------------------------------------------------- 618 * Macros. 619 *--------------------------------------------------------------- 620 */ 621 #define DM_NAME "device-mapper" 622 623 #define DM_FMT(fmt) DM_NAME ": " DM_MSG_PREFIX ": " fmt "\n" 624 625 #define DMCRIT(fmt, ...) pr_crit(DM_FMT(fmt), ##__VA_ARGS__) 626 627 #define DMERR(fmt, ...) pr_err(DM_FMT(fmt), ##__VA_ARGS__) 628 #define DMERR_LIMIT(fmt, ...) pr_err_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 629 #define DMWARN(fmt, ...) pr_warn(DM_FMT(fmt), ##__VA_ARGS__) 630 #define DMWARN_LIMIT(fmt, ...) pr_warn_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 631 #define DMINFO(fmt, ...) pr_info(DM_FMT(fmt), ##__VA_ARGS__) 632 #define DMINFO_LIMIT(fmt, ...) pr_info_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 633 634 #define DMDEBUG(fmt, ...) pr_debug(DM_FMT(fmt), ##__VA_ARGS__) 635 #define DMDEBUG_LIMIT(fmt, ...) pr_debug_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 636 637 #define DMEMIT(x...) (sz += ((sz >= maxlen) ? 0 : scnprintf(result + sz, maxlen - sz, x))) 638 639 #define DMEMIT_TARGET_NAME_VERSION(y) \ 640 DMEMIT("target_name=%s,target_version=%u.%u.%u", \ 641 (y)->name, (y)->version[0], (y)->version[1], (y)->version[2]) 642 643 /** 644 * module_dm() - Helper macro for DM targets that don't do anything 645 * special in their module_init and module_exit. 646 * Each module may only use this macro once, and calling it replaces 647 * module_init() and module_exit(). 648 * 649 * @name: DM target's name 650 */ 651 #define module_dm(name) \ 652 static int __init dm_##name##_init(void) \ 653 { \ 654 return dm_register_target(&(name##_target)); \ 655 } \ 656 module_init(dm_##name##_init) \ 657 static void __exit dm_##name##_exit(void) \ 658 { \ 659 dm_unregister_target(&(name##_target)); \ 660 } \ 661 module_exit(dm_##name##_exit) 662 663 /* 664 * Definitions of return values from target end_io function. 665 */ 666 #define DM_ENDIO_DONE 0 667 #define DM_ENDIO_INCOMPLETE 1 668 #define DM_ENDIO_REQUEUE 2 669 #define DM_ENDIO_DELAY_REQUEUE 3 670 671 /* 672 * Definitions of return values from target map function. 673 */ 674 #define DM_MAPIO_SUBMITTED 0 675 #define DM_MAPIO_REMAPPED 1 676 #define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE 677 #define DM_MAPIO_DELAY_REQUEUE DM_ENDIO_DELAY_REQUEUE 678 #define DM_MAPIO_KILL 4 679 680 #define dm_sector_div64(x, y)( \ 681 { \ 682 u64 _res; \ 683 (x) = div64_u64_rem(x, y, &_res); \ 684 _res; \ 685 } \ 686 ) 687 688 /* 689 * Ceiling(n / sz) 690 */ 691 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) 692 693 #define dm_sector_div_up(n, sz) ( \ 694 { \ 695 sector_t _r = ((n) + (sz) - 1); \ 696 sector_div(_r, (sz)); \ 697 _r; \ 698 } \ 699 ) 700 701 /* 702 * ceiling(n / size) * size 703 */ 704 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) 705 706 /* 707 * Sector offset taken relative to the start of the target instead of 708 * relative to the start of the device. 709 */ 710 #define dm_target_offset(ti, sector) ((sector) - (ti)->begin) 711 712 static inline sector_t to_sector(unsigned long long n) 713 { 714 return (n >> SECTOR_SHIFT); 715 } 716 717 static inline unsigned long to_bytes(sector_t n) 718 { 719 return (n << SECTOR_SHIFT); 720 } 721 722 #endif /* _LINUX_DEVICE_MAPPER_H */ 723