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 #define DM_TARGET_ATOMIC_WRITES 0x00000400 303 #define dm_target_supports_atomic_writes(type) ((type)->features & DM_TARGET_ATOMIC_WRITES) 304 305 struct dm_target { 306 struct dm_table *table; 307 struct target_type *type; 308 309 /* target limits */ 310 sector_t begin; 311 sector_t len; 312 313 /* If non-zero, maximum size of I/O submitted to a target. */ 314 uint32_t max_io_len; 315 316 /* 317 * A number of zero-length barrier bios that will be submitted 318 * to the target for the purpose of flushing cache. 319 * 320 * The bio number can be accessed with dm_bio_get_target_bio_nr. 321 * It is a responsibility of the target driver to remap these bios 322 * to the real underlying devices. 323 */ 324 unsigned int num_flush_bios; 325 326 /* 327 * The number of discard bios that will be submitted to the target. 328 * The bio number can be accessed with dm_bio_get_target_bio_nr. 329 */ 330 unsigned int num_discard_bios; 331 332 /* 333 * The number of secure erase bios that will be submitted to the target. 334 * The bio number can be accessed with dm_bio_get_target_bio_nr. 335 */ 336 unsigned int num_secure_erase_bios; 337 338 /* 339 * The number of WRITE ZEROES bios that will be submitted to the target. 340 * The bio number can be accessed with dm_bio_get_target_bio_nr. 341 */ 342 unsigned int num_write_zeroes_bios; 343 344 /* 345 * The minimum number of extra bytes allocated in each io for the 346 * target to use. 347 */ 348 unsigned int per_io_data_size; 349 350 /* target specific data */ 351 void *private; 352 353 /* Used to provide an error string from the ctr */ 354 char *error; 355 356 /* 357 * Set if this target needs to receive flushes regardless of 358 * whether or not its underlying devices have support. 359 */ 360 bool flush_supported:1; 361 362 /* 363 * Set if this target needs to receive discards regardless of 364 * whether or not its underlying devices have support. 365 */ 366 bool discards_supported:1; 367 368 /* 369 * Automatically set by dm-core if this target supports 370 * REQ_OP_ZONE_RESET_ALL. Otherwise, this operation will be emulated 371 * using REQ_OP_ZONE_RESET. Target drivers must not set this manually. 372 */ 373 bool zone_reset_all_supported:1; 374 375 /* 376 * Set if this target requires that discards be split on 377 * 'max_discard_sectors' boundaries. 378 */ 379 bool max_discard_granularity:1; 380 381 /* 382 * Set if we need to limit the number of in-flight bios when swapping. 383 */ 384 bool limit_swap_bios:1; 385 386 /* 387 * Set if this target implements a zoned device and needs emulation of 388 * zone append operations using regular writes. 389 */ 390 bool emulate_zone_append:1; 391 392 /* 393 * Set if the target will submit IO using dm_submit_bio_remap() 394 * after returning DM_MAPIO_SUBMITTED from its map function. 395 */ 396 bool accounts_remapped_io:1; 397 398 /* 399 * Set if the target will submit the DM bio without first calling 400 * bio_set_dev(). NOTE: ideally a target should _not_ need this. 401 */ 402 bool needs_bio_set_dev:1; 403 404 /* 405 * Set if the target supports flush optimization. If all the targets in 406 * a table have flush_bypasses_map set, the dm core will not send 407 * flushes to the targets via a ->map method. It will iterate over 408 * dm_table->devices and send flushes to the devices directly. This 409 * optimization reduces the number of flushes being sent when multiple 410 * targets in a table use the same underlying device. 411 * 412 * This optimization may be enabled on targets that just pass the 413 * flushes to the underlying devices without performing any other 414 * actions on the flush request. Currently, dm-linear and dm-stripe 415 * support it. 416 */ 417 bool flush_bypasses_map:1; 418 419 /* 420 * Set if the target calls bio_integrity_alloc on bios received 421 * in the map method. 422 */ 423 bool mempool_needs_integrity:1; 424 }; 425 426 void *dm_per_bio_data(struct bio *bio, size_t data_size); 427 struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size); 428 unsigned int dm_bio_get_target_bio_nr(const struct bio *bio); 429 430 u64 dm_start_time_ns_from_clone(struct bio *bio); 431 432 int dm_register_target(struct target_type *t); 433 void dm_unregister_target(struct target_type *t); 434 435 /* 436 * Target argument parsing. 437 */ 438 struct dm_arg_set { 439 unsigned int argc; 440 char **argv; 441 }; 442 443 /* 444 * The minimum and maximum value of a numeric argument, together with 445 * the error message to use if the number is found to be outside that range. 446 */ 447 struct dm_arg { 448 unsigned int min; 449 unsigned int max; 450 char *error; 451 }; 452 453 /* 454 * Validate the next argument, either returning it as *value or, if invalid, 455 * returning -EINVAL and setting *error. 456 */ 457 int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set, 458 unsigned int *value, char **error); 459 460 /* 461 * Process the next argument as the start of a group containing between 462 * arg->min and arg->max further arguments. Either return the size as 463 * *num_args or, if invalid, return -EINVAL and set *error. 464 */ 465 int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set, 466 unsigned int *num_args, char **error); 467 468 /* 469 * Return the current argument and shift to the next. 470 */ 471 const char *dm_shift_arg(struct dm_arg_set *as); 472 473 /* 474 * Move through num_args arguments. 475 */ 476 void dm_consume_args(struct dm_arg_set *as, unsigned int num_args); 477 478 /* 479 *---------------------------------------------------------------- 480 * Functions for creating and manipulating mapped devices. 481 * Drop the reference with dm_put when you finish with the object. 482 *---------------------------------------------------------------- 483 */ 484 485 /* 486 * DM_ANY_MINOR chooses the next available minor number. 487 */ 488 #define DM_ANY_MINOR (-1) 489 int dm_create(int minor, struct mapped_device **md); 490 491 /* 492 * Reference counting for md. 493 */ 494 struct mapped_device *dm_get_md(dev_t dev); 495 void dm_get(struct mapped_device *md); 496 int dm_hold(struct mapped_device *md); 497 void dm_put(struct mapped_device *md); 498 499 /* 500 * An arbitrary pointer may be stored alongside a mapped device. 501 */ 502 void dm_set_mdptr(struct mapped_device *md, void *ptr); 503 void *dm_get_mdptr(struct mapped_device *md); 504 505 /* 506 * A device can still be used while suspended, but I/O is deferred. 507 */ 508 int dm_suspend(struct mapped_device *md, unsigned int suspend_flags); 509 int dm_resume(struct mapped_device *md); 510 511 /* 512 * Event functions. 513 */ 514 uint32_t dm_get_event_nr(struct mapped_device *md); 515 int dm_wait_event(struct mapped_device *md, int event_nr); 516 uint32_t dm_next_uevent_seq(struct mapped_device *md); 517 void dm_uevent_add(struct mapped_device *md, struct list_head *elist); 518 519 /* 520 * Info functions. 521 */ 522 const char *dm_device_name(struct mapped_device *md); 523 int dm_copy_name_and_uuid(struct mapped_device *md, char *name, char *uuid); 524 struct gendisk *dm_disk(struct mapped_device *md); 525 int dm_suspended(struct dm_target *ti); 526 int dm_post_suspending(struct dm_target *ti); 527 int dm_noflush_suspending(struct dm_target *ti); 528 void dm_accept_partial_bio(struct bio *bio, unsigned int n_sectors); 529 void dm_submit_bio_remap(struct bio *clone, struct bio *tgt_clone); 530 531 #ifdef CONFIG_BLK_DEV_ZONED 532 struct dm_report_zones_args { 533 struct dm_target *tgt; 534 sector_t next_sector; 535 536 void *orig_data; 537 report_zones_cb orig_cb; 538 unsigned int zone_idx; 539 540 /* must be filled by ->report_zones before calling dm_report_zones_cb */ 541 sector_t start; 542 }; 543 int dm_report_zones(struct block_device *bdev, sector_t start, sector_t sector, 544 struct dm_report_zones_args *args, unsigned int nr_zones); 545 #endif /* CONFIG_BLK_DEV_ZONED */ 546 547 /* 548 * Device mapper functions to parse and create devices specified by the 549 * parameter "dm-mod.create=" 550 */ 551 int __init dm_early_create(struct dm_ioctl *dmi, 552 struct dm_target_spec **spec_array, 553 char **target_params_array); 554 555 /* 556 * Geometry functions. 557 */ 558 int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo); 559 int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo); 560 561 /* 562 *--------------------------------------------------------------- 563 * Functions for manipulating device-mapper tables. 564 *--------------------------------------------------------------- 565 */ 566 567 /* 568 * First create an empty table. 569 */ 570 int dm_table_create(struct dm_table **result, blk_mode_t mode, 571 unsigned int num_targets, struct mapped_device *md); 572 573 /* 574 * Then call this once for each target. 575 */ 576 int dm_table_add_target(struct dm_table *t, const char *type, 577 sector_t start, sector_t len, char *params); 578 579 /* 580 * Target can use this to set the table's type. 581 * Can only ever be called from a target's ctr. 582 * Useful for "hybrid" target (supports both bio-based 583 * and request-based). 584 */ 585 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type); 586 587 /* 588 * Finally call this to make the table ready for use. 589 */ 590 int dm_table_complete(struct dm_table *t); 591 592 /* 593 * Destroy the table when finished. 594 */ 595 void dm_table_destroy(struct dm_table *t); 596 597 /* 598 * Target may require that it is never sent I/O larger than len. 599 */ 600 int __must_check dm_set_target_max_io_len(struct dm_target *ti, sector_t len); 601 602 /* 603 * Table reference counting. 604 */ 605 struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx); 606 void dm_put_live_table(struct mapped_device *md, int srcu_idx); 607 void dm_sync_table(struct mapped_device *md); 608 609 /* 610 * Queries 611 */ 612 sector_t dm_table_get_size(struct dm_table *t); 613 blk_mode_t dm_table_get_mode(struct dm_table *t); 614 struct mapped_device *dm_table_get_md(struct dm_table *t); 615 const char *dm_table_device_name(struct dm_table *t); 616 617 /* 618 * Trigger an event. 619 */ 620 void dm_table_event(struct dm_table *t); 621 622 /* 623 * Run the queue for request-based targets. 624 */ 625 void dm_table_run_md_queue_async(struct dm_table *t); 626 627 /* 628 * The device must be suspended before calling this method. 629 * Returns the previous table, which the caller must destroy. 630 */ 631 struct dm_table *dm_swap_table(struct mapped_device *md, 632 struct dm_table *t); 633 634 /* 635 * Table blk_crypto_profile functions 636 */ 637 void dm_destroy_crypto_profile(struct blk_crypto_profile *profile); 638 639 /* 640 *--------------------------------------------------------------- 641 * Macros. 642 *--------------------------------------------------------------- 643 */ 644 #define DM_NAME "device-mapper" 645 646 #define DM_FMT(fmt) DM_NAME ": " DM_MSG_PREFIX ": " fmt "\n" 647 648 #define DMCRIT(fmt, ...) pr_crit(DM_FMT(fmt), ##__VA_ARGS__) 649 650 #define DMERR(fmt, ...) pr_err(DM_FMT(fmt), ##__VA_ARGS__) 651 #define DMERR_LIMIT(fmt, ...) pr_err_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 652 #define DMWARN(fmt, ...) pr_warn(DM_FMT(fmt), ##__VA_ARGS__) 653 #define DMWARN_LIMIT(fmt, ...) pr_warn_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 654 #define DMINFO(fmt, ...) pr_info(DM_FMT(fmt), ##__VA_ARGS__) 655 #define DMINFO_LIMIT(fmt, ...) pr_info_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 656 657 #define DMDEBUG(fmt, ...) pr_debug(DM_FMT(fmt), ##__VA_ARGS__) 658 #define DMDEBUG_LIMIT(fmt, ...) pr_debug_ratelimited(DM_FMT(fmt), ##__VA_ARGS__) 659 660 #define DMEMIT(x...) (sz += ((sz >= maxlen) ? 0 : scnprintf(result + sz, maxlen - sz, x))) 661 662 #define DMEMIT_TARGET_NAME_VERSION(y) \ 663 DMEMIT("target_name=%s,target_version=%u.%u.%u", \ 664 (y)->name, (y)->version[0], (y)->version[1], (y)->version[2]) 665 666 /** 667 * module_dm() - Helper macro for DM targets that don't do anything 668 * special in their module_init and module_exit. 669 * Each module may only use this macro once, and calling it replaces 670 * module_init() and module_exit(). 671 * 672 * @name: DM target's name 673 */ 674 #define module_dm(name) \ 675 static int __init dm_##name##_init(void) \ 676 { \ 677 return dm_register_target(&(name##_target)); \ 678 } \ 679 module_init(dm_##name##_init) \ 680 static void __exit dm_##name##_exit(void) \ 681 { \ 682 dm_unregister_target(&(name##_target)); \ 683 } \ 684 module_exit(dm_##name##_exit) 685 686 /* 687 * Definitions of return values from target end_io function. 688 */ 689 #define DM_ENDIO_DONE 0 690 #define DM_ENDIO_INCOMPLETE 1 691 #define DM_ENDIO_REQUEUE 2 692 #define DM_ENDIO_DELAY_REQUEUE 3 693 694 /* 695 * Definitions of return values from target map function. 696 */ 697 #define DM_MAPIO_SUBMITTED 0 698 #define DM_MAPIO_REMAPPED 1 699 #define DM_MAPIO_REQUEUE DM_ENDIO_REQUEUE 700 #define DM_MAPIO_DELAY_REQUEUE DM_ENDIO_DELAY_REQUEUE 701 #define DM_MAPIO_KILL 4 702 703 #define dm_sector_div64(x, y)( \ 704 { \ 705 u64 _res; \ 706 (x) = div64_u64_rem(x, y, &_res); \ 707 _res; \ 708 } \ 709 ) 710 711 /* 712 * Ceiling(n / sz) 713 */ 714 #define dm_div_up(n, sz) (((n) + (sz) - 1) / (sz)) 715 716 #define dm_sector_div_up(n, sz) ( \ 717 { \ 718 sector_t _r = ((n) + (sz) - 1); \ 719 sector_div(_r, (sz)); \ 720 _r; \ 721 } \ 722 ) 723 724 /* 725 * ceiling(n / size) * size 726 */ 727 #define dm_round_up(n, sz) (dm_div_up((n), (sz)) * (sz)) 728 729 /* 730 * Sector offset taken relative to the start of the target instead of 731 * relative to the start of the device. 732 */ 733 #define dm_target_offset(ti, sector) ((sector) - (ti)->begin) 734 735 static inline sector_t to_sector(unsigned long long n) 736 { 737 return (n >> SECTOR_SHIFT); 738 } 739 740 static inline unsigned long to_bytes(sector_t n) 741 { 742 return (n << SECTOR_SHIFT); 743 } 744 745 #endif /* _LINUX_DEVICE_MAPPER_H */ 746