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 * Helper function for getting devices 184 */ 185 int dm_devt_from_path(const char *path, dev_t *dev_p); 186 187 /* 188 * Information about a target type 189 */ 190 191 struct target_type { 192 uint64_t features; 193 const char *name; 194 struct module *module; 195 unsigned int version[3]; 196 dm_ctr_fn ctr; 197 dm_dtr_fn dtr; 198 dm_map_fn map; 199 dm_clone_and_map_request_fn clone_and_map_rq; 200 dm_release_clone_request_fn release_clone_rq; 201 dm_endio_fn end_io; 202 dm_request_endio_fn rq_end_io; 203 dm_presuspend_fn presuspend; 204 dm_presuspend_undo_fn presuspend_undo; 205 dm_postsuspend_fn postsuspend; 206 dm_preresume_fn preresume; 207 dm_resume_fn resume; 208 dm_status_fn status; 209 dm_message_fn message; 210 dm_prepare_ioctl_fn prepare_ioctl; 211 dm_report_zones_fn report_zones; 212 dm_busy_fn busy; 213 dm_iterate_devices_fn iterate_devices; 214 dm_io_hints_fn io_hints; 215 dm_dax_direct_access_fn direct_access; 216 dm_dax_zero_page_range_fn dax_zero_page_range; 217 dm_dax_recovery_write_fn dax_recovery_write; 218 219 /* For internal device-mapper use. */ 220 struct list_head list; 221 }; 222 223 /* 224 * Target features 225 */ 226 227 /* 228 * Any table that contains an instance of this target must have only one. 229 */ 230 #define DM_TARGET_SINGLETON 0x00000001 231 #define dm_target_needs_singleton(type) ((type)->features & DM_TARGET_SINGLETON) 232 233 /* 234 * Indicates that a target does not support read-only devices. 235 */ 236 #define DM_TARGET_ALWAYS_WRITEABLE 0x00000002 237 #define dm_target_always_writeable(type) \ 238 ((type)->features & DM_TARGET_ALWAYS_WRITEABLE) 239 240 /* 241 * Any device that contains a table with an instance of this target may never 242 * have tables containing any different target type. 243 */ 244 #define DM_TARGET_IMMUTABLE 0x00000004 245 #define dm_target_is_immutable(type) ((type)->features & DM_TARGET_IMMUTABLE) 246 247 /* 248 * Indicates that a target may replace any target; even immutable targets. 249 * .map, .map_rq, .clone_and_map_rq and .release_clone_rq are all defined. 250 */ 251 #define DM_TARGET_WILDCARD 0x00000008 252 #define dm_target_is_wildcard(type) ((type)->features & DM_TARGET_WILDCARD) 253 254 /* 255 * A target implements own bio data integrity. 256 */ 257 #define DM_TARGET_INTEGRITY 0x00000010 258 #define dm_target_has_integrity(type) ((type)->features & DM_TARGET_INTEGRITY) 259 260 /* 261 * A target passes integrity data to the lower device. 262 */ 263 #define DM_TARGET_PASSES_INTEGRITY 0x00000020 264 #define dm_target_passes_integrity(type) ((type)->features & DM_TARGET_PASSES_INTEGRITY) 265 266 /* 267 * Indicates support for zoned block devices: 268 * - DM_TARGET_ZONED_HM: the target also supports host-managed zoned 269 * block devices but does not support combining different zoned models. 270 * - DM_TARGET_MIXED_ZONED_MODEL: the target supports combining multiple 271 * devices with different zoned models. 272 */ 273 #ifdef CONFIG_BLK_DEV_ZONED 274 #define DM_TARGET_ZONED_HM 0x00000040 275 #define dm_target_supports_zoned_hm(type) ((type)->features & DM_TARGET_ZONED_HM) 276 #else 277 #define DM_TARGET_ZONED_HM 0x00000000 278 #define dm_target_supports_zoned_hm(type) (false) 279 #endif 280 281 /* 282 * A target handles REQ_NOWAIT 283 */ 284 #define DM_TARGET_NOWAIT 0x00000080 285 #define dm_target_supports_nowait(type) ((type)->features & DM_TARGET_NOWAIT) 286 287 /* 288 * A target supports passing through inline crypto support. 289 */ 290 #define DM_TARGET_PASSES_CRYPTO 0x00000100 291 #define dm_target_passes_crypto(type) ((type)->features & DM_TARGET_PASSES_CRYPTO) 292 293 #ifdef CONFIG_BLK_DEV_ZONED 294 #define DM_TARGET_MIXED_ZONED_MODEL 0x00000200 295 #define dm_target_supports_mixed_zoned_model(type) \ 296 ((type)->features & DM_TARGET_MIXED_ZONED_MODEL) 297 #else 298 #define DM_TARGET_MIXED_ZONED_MODEL 0x00000000 299 #define dm_target_supports_mixed_zoned_model(type) (false) 300 #endif 301 302 struct dm_target { 303 struct dm_table *table; 304 struct target_type *type; 305 306 /* target limits */ 307 sector_t begin; 308 sector_t len; 309 310 /* If non-zero, maximum size of I/O submitted to a target. */ 311 uint32_t max_io_len; 312 313 /* 314 * A number of zero-length barrier bios that will be submitted 315 * to the target for the purpose of flushing cache. 316 * 317 * The bio number can be accessed with dm_bio_get_target_bio_nr. 318 * It is a responsibility of the target driver to remap these bios 319 * to the real underlying devices. 320 */ 321 unsigned int num_flush_bios; 322 323 /* 324 * The number of discard 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_discard_bios; 328 329 /* 330 * The number of secure erase 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_secure_erase_bios; 334 335 /* 336 * The number of WRITE ZEROES bios that will be submitted to the target. 337 * The bio number can be accessed with dm_bio_get_target_bio_nr. 338 */ 339 unsigned int num_write_zeroes_bios; 340 341 /* 342 * The minimum number of extra bytes allocated in each io for the 343 * target to use. 344 */ 345 unsigned int per_io_data_size; 346 347 /* target specific data */ 348 void *private; 349 350 /* Used to provide an error string from the ctr */ 351 char *error; 352 353 /* 354 * Set if this target needs to receive flushes regardless of 355 * whether or not its underlying devices have support. 356 */ 357 bool flush_supported:1; 358 359 /* 360 * Set if this target needs to receive discards regardless of 361 * whether or not its underlying devices have support. 362 */ 363 bool discards_supported:1; 364 365 /* 366 * Automatically set by dm-core if this target supports 367 * REQ_OP_ZONE_RESET_ALL. Otherwise, this operation will be emulated 368 * using REQ_OP_ZONE_RESET. Target drivers must not set this manually. 369 */ 370 bool zone_reset_all_supported:1; 371 372 /* 373 * Set if this target requires that discards be split on 374 * 'max_discard_sectors' boundaries. 375 */ 376 bool max_discard_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 * Set if the target supports flush optimization. If all the targets in 403 * a table have flush_bypasses_map set, the dm core will not send 404 * flushes to the targets via a ->map method. It will iterate over 405 * dm_table->devices and send flushes to the devices directly. This 406 * optimization reduces the number of flushes being sent when multiple 407 * targets in a table use the same underlying device. 408 * 409 * This optimization may be enabled on targets that just pass the 410 * flushes to the underlying devices without performing any other 411 * actions on the flush request. Currently, dm-linear and dm-stripe 412 * support it. 413 */ 414 bool flush_bypasses_map:1; 415 416 /* 417 * Set if the target calls bio_integrity_alloc on bios received 418 * in the map method. 419 */ 420 bool mempool_needs_integrity:1; 421 }; 422 423 void *dm_per_bio_data(struct bio *bio, size_t data_size); 424 struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size); 425 unsigned int dm_bio_get_target_bio_nr(const struct bio *bio); 426 427 u64 dm_start_time_ns_from_clone(struct bio *bio); 428 429 int dm_register_target(struct target_type *t); 430 void dm_unregister_target(struct target_type *t); 431 432 /* 433 * Target argument parsing. 434 */ 435 struct dm_arg_set { 436 unsigned int argc; 437 char **argv; 438 }; 439 440 /* 441 * The minimum and maximum value of a numeric argument, together with 442 * the error message to use if the number is found to be outside that range. 443 */ 444 struct dm_arg { 445 unsigned int min; 446 unsigned int max; 447 char *error; 448 }; 449 450 /* 451 * Validate the next argument, either returning it as *value or, if invalid, 452 * returning -EINVAL and setting *error. 453 */ 454 int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set, 455 unsigned int *value, char **error); 456 457 /* 458 * Process the next argument as the start of a group containing between 459 * arg->min and arg->max further arguments. Either return the size as 460 * *num_args or, if invalid, return -EINVAL and set *error. 461 */ 462 int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set, 463 unsigned int *num_args, char **error); 464 465 /* 466 * Return the current argument and shift to the next. 467 */ 468 const char *dm_shift_arg(struct dm_arg_set *as); 469 470 /* 471 * Move through num_args arguments. 472 */ 473 void dm_consume_args(struct dm_arg_set *as, unsigned int num_args); 474 475 /* 476 *---------------------------------------------------------------- 477 * Functions for creating and manipulating mapped devices. 478 * Drop the reference with dm_put when you finish with the object. 479 *---------------------------------------------------------------- 480 */ 481 482 /* 483 * DM_ANY_MINOR chooses the next available minor number. 484 */ 485 #define DM_ANY_MINOR (-1) 486 int dm_create(int minor, struct mapped_device **md); 487 488 /* 489 * Reference counting for md. 490 */ 491 struct mapped_device *dm_get_md(dev_t dev); 492 void dm_get(struct mapped_device *md); 493 int dm_hold(struct mapped_device *md); 494 void dm_put(struct mapped_device *md); 495 496 /* 497 * An arbitrary pointer may be stored alongside a mapped device. 498 */ 499 void dm_set_mdptr(struct mapped_device *md, void *ptr); 500 void *dm_get_mdptr(struct mapped_device *md); 501 502 /* 503 * A device can still be used while suspended, but I/O is deferred. 504 */ 505 int dm_suspend(struct mapped_device *md, unsigned int suspend_flags); 506 int dm_resume(struct mapped_device *md); 507 508 /* 509 * Event functions. 510 */ 511 uint32_t dm_get_event_nr(struct mapped_device *md); 512 int dm_wait_event(struct mapped_device *md, int event_nr); 513 uint32_t dm_next_uevent_seq(struct mapped_device *md); 514 void dm_uevent_add(struct mapped_device *md, struct list_head *elist); 515 516 /* 517 * Info functions. 518 */ 519 const char *dm_device_name(struct mapped_device *md); 520 int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid); 521 struct gendisk *dm_disk(struct mapped_device *md); 522 int dm_suspended(struct dm_target *ti); 523 int dm_post_suspending(struct dm_target *ti); 524 int dm_noflush_suspending(struct dm_target *ti); 525 void dm_accept_partial_bio(struct bio *bio, unsigned int n_sectors); 526 void dm_submit_bio_remap(struct bio *clone, struct bio *tgt_clone); 527 528 #ifdef CONFIG_BLK_DEV_ZONED 529 struct dm_report_zones_args { 530 struct dm_target *tgt; 531 sector_t next_sector; 532 533 void *orig_data; 534 report_zones_cb orig_cb; 535 unsigned int zone_idx; 536 537 /* must be filled by ->report_zones before calling dm_report_zones_cb */ 538 sector_t start; 539 }; 540 int dm_report_zones(struct block_device *bdev, sector_t start, sector_t sector, 541 struct dm_report_zones_args *args, unsigned int nr_zones); 542 #endif /* CONFIG_BLK_DEV_ZONED */ 543 544 /* 545 * Device mapper functions to parse and create devices specified by the 546 * parameter "dm-mod.create=" 547 */ 548 int __init dm_early_create(struct dm_ioctl *dmi, 549 struct dm_target_spec **spec_array, 550 char **target_params_array); 551 552 /* 553 * Geometry functions. 554 */ 555 int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo); 556 int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo); 557 558 /* 559 *--------------------------------------------------------------- 560 * Functions for manipulating device-mapper tables. 561 *--------------------------------------------------------------- 562 */ 563 564 /* 565 * First create an empty table. 566 */ 567 int dm_table_create(struct dm_table **result, blk_mode_t mode, 568 unsigned int num_targets, struct mapped_device *md); 569 570 /* 571 * Then call this once for each target. 572 */ 573 int dm_table_add_target(struct dm_table *t, const char *type, 574 sector_t start, sector_t len, char *params); 575 576 /* 577 * Target can use this to set the table's type. 578 * Can only ever be called from a target's ctr. 579 * Useful for "hybrid" target (supports both bio-based 580 * and request-based). 581 */ 582 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type); 583 584 /* 585 * Finally call this to make the table ready for use. 586 */ 587 int dm_table_complete(struct dm_table *t); 588 589 /* 590 * Destroy the table when finished. 591 */ 592 void dm_table_destroy(struct dm_table *t); 593 594 /* 595 * Target may require that it is never sent I/O larger than len. 596 */ 597 int __must_check dm_set_target_max_io_len(struct dm_target *ti, sector_t len); 598 599 /* 600 * Table reference counting. 601 */ 602 struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx); 603 void dm_put_live_table(struct mapped_device *md, int srcu_idx); 604 void dm_sync_table(struct mapped_device *md); 605 606 /* 607 * Queries 608 */ 609 sector_t dm_table_get_size(struct dm_table *t); 610 blk_mode_t dm_table_get_mode(struct dm_table *t); 611 struct mapped_device *dm_table_get_md(struct dm_table *t); 612 const char *dm_table_device_name(struct dm_table *t); 613 614 /* 615 * Trigger an event. 616 */ 617 void dm_table_event(struct dm_table *t); 618 619 /* 620 * Run the queue for request-based targets. 621 */ 622 void dm_table_run_md_queue_async(struct dm_table *t); 623 624 /* 625 * The device must be suspended before calling this method. 626 * Returns the previous table, which the caller must destroy. 627 */ 628 struct dm_table *dm_swap_table(struct mapped_device *md, 629 struct dm_table *t); 630 631 /* 632 * Table blk_crypto_profile functions 633 */ 634 void dm_destroy_crypto_profile(struct blk_crypto_profile *profile); 635 636 /* 637 *--------------------------------------------------------------- 638 * Macros. 639 *--------------------------------------------------------------- 640 */ 641 #define DM_NAME "device-mapper" 642 643 #define DM_FMT(fmt) DM_NAME ": " DM_MSG_PREFIX ": " fmt "\n" 644 645 #define DMCRIT(fmt, ...) pr_crit(DM_FMT(fmt), ##__VA_ARGS__) 646 647 #define DMERR(fmt, ...) pr_err(DM_FMT(fmt), ##__VA_ARGS__) 648 #define DMERR_LIMIT(fmt, ...) pr_err_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 649 #define DMWARN(fmt, ...) pr_warn(DM_FMT(fmt), ##__VA_ARGS__) 650 #define DMWARN_LIMIT(fmt, ...) pr_warn_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 651 #define DMINFO(fmt, ...) pr_info(DM_FMT(fmt), ##__VA_ARGS__) 652 #define DMINFO_LIMIT(fmt, ...) pr_info_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 653 654 #define DMDEBUG(fmt, ...) pr_debug(DM_FMT(fmt), ##__VA_ARGS__) 655 #define DMDEBUG_LIMIT(fmt, ...) pr_debug_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 656 657 #define DMEMIT(x...) (sz += ((sz >= maxlen) ? 0 : scnprintf(result + sz, maxlen - sz, x))) 658 659 #define DMEMIT_TARGET_NAME_VERSION(y) \ 660 DMEMIT("target_name=%s,target_version=%u.%u.%u", \ 661 (y)->name, (y)->version[0], (y)->version[1], (y)->version[2]) 662 663 /** 664 * module_dm() - Helper macro for DM targets that don't do anything 665 * special in their module_init and module_exit. 666 * Each module may only use this macro once, and calling it replaces 667 * module_init() and module_exit(). 668 * 669 * @name: DM target's name 670 */ 671 #define module_dm(name) \ 672 static int __init dm_##name##_init(void) \ 673 { \ 674 return dm_register_target(&(name##_target)); \ 675 } \ 676 module_init(dm_##name##_init) \ 677 static void __exit dm_##name##_exit(void) \ 678 { \ 679 dm_unregister_target(&(name##_target)); \ 680 } \ 681 module_exit(dm_##name##_exit) 682 683 /* 684 * Definitions of return values from target end_io function. 685 */ 686 #define DM_ENDIO_DONE 0 687 #define DM_ENDIO_INCOMPLETE 1 688 #define DM_ENDIO_REQUEUE 2 689 #define DM_ENDIO_DELAY_REQUEUE 3 690 691 /* 692 * Definitions of return values from target map function. 693 */ 694 #define DM_MAPIO_SUBMITTED 0 695 #define DM_MAPIO_REMAPPED 1 696 #define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE 697 #define DM_MAPIO_DELAY_REQUEUE DM_ENDIO_DELAY_REQUEUE 698 #define DM_MAPIO_KILL 4 699 700 #define dm_sector_div64(x, y)( \ 701 { \ 702 u64 _res; \ 703 (x) = div64_u64_rem(x, y, &_res); \ 704 _res; \ 705 } \ 706 ) 707 708 /* 709 * Ceiling(n / sz) 710 */ 711 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) 712 713 #define dm_sector_div_up(n, sz) ( \ 714 { \ 715 sector_t _r = ((n) + (sz) - 1); \ 716 sector_div(_r, (sz)); \ 717 _r; \ 718 } \ 719 ) 720 721 /* 722 * ceiling(n / size) * size 723 */ 724 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) 725 726 /* 727 * Sector offset taken relative to the start of the target instead of 728 * relative to the start of the device. 729 */ 730 #define dm_target_offset(ti, sector) ((sector) - (ti)->begin) 731 to_sector(unsigned long long n)732 static inline sector_t to_sector(unsigned long long n) 733 { 734 return (n >> SECTOR_SHIFT); 735 } 736 to_bytes(sector_t n)737 static inline unsigned long to_bytes(sector_t n) 738 { 739 return (n << SECTOR_SHIFT); 740 } 741 742 #endif /* _LINUX_DEVICE_MAPPER_H */ 743