1/* 2 * Copyright (C) 2001 Sistina Software (UK) Limited. 3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. 4 * 5 * This file is released under the GPL. 6 */ 7 8#include "dm-core.h" 9 10#include <linux/module.h> 11#include <linux/vmalloc.h> 12#include <linux/blkdev.h> 13#include <linux/namei.h> 14#include <linux/ctype.h> 15#include <linux/string.h> 16#include <linux/slab.h> 17#include <linux/interrupt.h> 18#include <linux/mutex.h> 19#include <linux/delay.h> 20#include <linux/atomic.h> 21#include <linux/blk-mq.h> 22#include <linux/mount.h> 23#include <linux/dax.h> 24 25#define DM_MSG_PREFIX "table" 26 27#define NODE_SIZE L1_CACHE_BYTES 28#define KEYS_PER_NODE (NODE_SIZE / sizeof(sector_t)) 29#define CHILDREN_PER_NODE (KEYS_PER_NODE + 1) 30 31/* 32 * Similar to ceiling(log_size(n)) 33 */ 34static unsigned int int_log(unsigned int n, unsigned int base) 35{ 36 int result = 0; 37 38 while (n > 1) { 39 n = dm_div_up(n, base); 40 result++; 41 } 42 43 return result; 44} 45 46/* 47 * Calculate the index of the child node of the n'th node k'th key. 48 */ 49static inline unsigned int get_child(unsigned int n, unsigned int k) 50{ 51 return (n * CHILDREN_PER_NODE) + k; 52} 53 54/* 55 * Return the n'th node of level l from table t. 56 */ 57static inline sector_t *get_node(struct dm_table *t, 58 unsigned int l, unsigned int n) 59{ 60 return t->index[l] + (n * KEYS_PER_NODE); 61} 62 63/* 64 * Return the highest key that you could lookup from the n'th 65 * node on level l of the btree. 66 */ 67static sector_t high(struct dm_table *t, unsigned int l, unsigned int n) 68{ 69 for (; l < t->depth - 1; l++) 70 n = get_child(n, CHILDREN_PER_NODE - 1); 71 72 if (n >= t->counts[l]) 73 return (sector_t) - 1; 74 75 return get_node(t, l, n)[KEYS_PER_NODE - 1]; 76} 77 78/* 79 * Fills in a level of the btree based on the highs of the level 80 * below it. 81 */ 82static int setup_btree_index(unsigned int l, struct dm_table *t) 83{ 84 unsigned int n, k; 85 sector_t *node; 86 87 for (n = 0U; n < t->counts[l]; n++) { 88 node = get_node(t, l, n); 89 90 for (k = 0U; k < KEYS_PER_NODE; k++) 91 node[k] = high(t, l + 1, get_child(n, k)); 92 } 93 94 return 0; 95} 96 97void *dm_vcalloc(unsigned long nmemb, unsigned long elem_size) 98{ 99 unsigned long size; 100 void *addr; 101 102 /* 103 * Check that we're not going to overflow. 104 */ 105 if (nmemb > (ULONG_MAX / elem_size)) 106 return NULL; 107 108 size = nmemb * elem_size; 109 addr = vzalloc(size); 110 111 return addr; 112} 113EXPORT_SYMBOL(dm_vcalloc); 114 115/* 116 * highs, and targets are managed as dynamic arrays during a 117 * table load. 118 */ 119static int alloc_targets(struct dm_table *t, unsigned int num) 120{ 121 sector_t *n_highs; 122 struct dm_target *n_targets; 123 124 /* 125 * Allocate both the target array and offset array at once. 126 */ 127 n_highs = (sector_t *) dm_vcalloc(num, sizeof(struct dm_target) + 128 sizeof(sector_t)); 129 if (!n_highs) 130 return -ENOMEM; 131 132 n_targets = (struct dm_target *) (n_highs + num); 133 134 memset(n_highs, -1, sizeof(*n_highs) * num); 135 vfree(t->highs); 136 137 t->num_allocated = num; 138 t->highs = n_highs; 139 t->targets = n_targets; 140 141 return 0; 142} 143 144int dm_table_create(struct dm_table **result, fmode_t mode, 145 unsigned num_targets, struct mapped_device *md) 146{ 147 struct dm_table *t; 148 149 if (num_targets > DM_MAX_TARGETS) 150 return -EOVERFLOW; 151 152 t = kzalloc(sizeof(*t), GFP_KERNEL); 153 154 if (!t) 155 return -ENOMEM; 156 157 INIT_LIST_HEAD(&t->devices); 158 159 if (!num_targets) 160 num_targets = KEYS_PER_NODE; 161 162 num_targets = dm_round_up(num_targets, KEYS_PER_NODE); 163 164 if (!num_targets) { 165 kfree(t); 166 return -EOVERFLOW; 167 } 168 169 if (alloc_targets(t, num_targets)) { 170 kfree(t); 171 return -ENOMEM; 172 } 173 174 t->type = DM_TYPE_NONE; 175 t->mode = mode; 176 t->md = md; 177 *result = t; 178 return 0; 179} 180 181static void free_devices(struct list_head *devices, struct mapped_device *md) 182{ 183 struct list_head *tmp, *next; 184 185 list_for_each_safe(tmp, next, devices) { 186 struct dm_dev_internal *dd = 187 list_entry(tmp, struct dm_dev_internal, list); 188 DMWARN("%s: dm_table_destroy: dm_put_device call missing for %s", 189 dm_device_name(md), dd->dm_dev->name); 190 dm_put_table_device(md, dd->dm_dev); 191 kfree(dd); 192 } 193} 194 195void dm_table_destroy(struct dm_table *t) 196{ 197 unsigned int i; 198 199 if (!t) 200 return; 201 202 /* free the indexes */ 203 if (t->depth >= 2) 204 vfree(t->index[t->depth - 2]); 205 206 /* free the targets */ 207 for (i = 0; i < t->num_targets; i++) { 208 struct dm_target *tgt = t->targets + i; 209 210 if (tgt->type->dtr) 211 tgt->type->dtr(tgt); 212 213 dm_put_target_type(tgt->type); 214 } 215 216 vfree(t->highs); 217 218 /* free the device list */ 219 free_devices(&t->devices, t->md); 220 221 dm_free_md_mempools(t->mempools); 222 223 kfree(t); 224} 225 226/* 227 * See if we've already got a device in the list. 228 */ 229static struct dm_dev_internal *find_device(struct list_head *l, dev_t dev) 230{ 231 struct dm_dev_internal *dd; 232 233 list_for_each_entry (dd, l, list) 234 if (dd->dm_dev->bdev->bd_dev == dev) 235 return dd; 236 237 return NULL; 238} 239 240/* 241 * If possible, this checks an area of a destination device is invalid. 242 */ 243static int device_area_is_invalid(struct dm_target *ti, struct dm_dev *dev, 244 sector_t start, sector_t len, void *data) 245{ 246 struct queue_limits *limits = data; 247 struct block_device *bdev = dev->bdev; 248 sector_t dev_size = 249 i_size_read(bdev->bd_inode) >> SECTOR_SHIFT; 250 unsigned short logical_block_size_sectors = 251 limits->logical_block_size >> SECTOR_SHIFT; 252 char b[BDEVNAME_SIZE]; 253 254 if (!dev_size) 255 return 0; 256 257 if ((start >= dev_size) || (start + len > dev_size)) { 258 DMWARN("%s: %s too small for target: " 259 "start=%llu, len=%llu, dev_size=%llu", 260 dm_device_name(ti->table->md), bdevname(bdev, b), 261 (unsigned long long)start, 262 (unsigned long long)len, 263 (unsigned long long)dev_size); 264 return 1; 265 } 266 267 /* 268 * If the target is mapped to zoned block device(s), check 269 * that the zones are not partially mapped. 270 */ 271 if (bdev_zoned_model(bdev) != BLK_ZONED_NONE) { 272 unsigned int zone_sectors = bdev_zone_sectors(bdev); 273 274 if (start & (zone_sectors - 1)) { 275 DMWARN("%s: start=%llu not aligned to h/w zone size %u of %s", 276 dm_device_name(ti->table->md), 277 (unsigned long long)start, 278 zone_sectors, bdevname(bdev, b)); 279 return 1; 280 } 281 282 /* 283 * Note: The last zone of a zoned block device may be smaller 284 * than other zones. So for a target mapping the end of a 285 * zoned block device with such a zone, len would not be zone 286 * aligned. We do not allow such last smaller zone to be part 287 * of the mapping here to ensure that mappings with multiple 288 * devices do not end up with a smaller zone in the middle of 289 * the sector range. 290 */ 291 if (len & (zone_sectors - 1)) { 292 DMWARN("%s: len=%llu not aligned to h/w zone size %u of %s", 293 dm_device_name(ti->table->md), 294 (unsigned long long)len, 295 zone_sectors, bdevname(bdev, b)); 296 return 1; 297 } 298 } 299 300 if (logical_block_size_sectors <= 1) 301 return 0; 302 303 if (start & (logical_block_size_sectors - 1)) { 304 DMWARN("%s: start=%llu not aligned to h/w " 305 "logical block size %u of %s", 306 dm_device_name(ti->table->md), 307 (unsigned long long)start, 308 limits->logical_block_size, bdevname(bdev, b)); 309 return 1; 310 } 311 312 if (len & (logical_block_size_sectors - 1)) { 313 DMWARN("%s: len=%llu not aligned to h/w " 314 "logical block size %u of %s", 315 dm_device_name(ti->table->md), 316 (unsigned long long)len, 317 limits->logical_block_size, bdevname(bdev, b)); 318 return 1; 319 } 320 321 return 0; 322} 323 324/* 325 * This upgrades the mode on an already open dm_dev, being 326 * careful to leave things as they were if we fail to reopen the 327 * device and not to touch the existing bdev field in case 328 * it is accessed concurrently. 329 */ 330static int upgrade_mode(struct dm_dev_internal *dd, fmode_t new_mode, 331 struct mapped_device *md) 332{ 333 int r; 334 struct dm_dev *old_dev, *new_dev; 335 336 old_dev = dd->dm_dev; 337 338 r = dm_get_table_device(md, dd->dm_dev->bdev->bd_dev, 339 dd->dm_dev->mode | new_mode, &new_dev); 340 if (r) 341 return r; 342 343 dd->dm_dev = new_dev; 344 dm_put_table_device(md, old_dev); 345 346 return 0; 347} 348 349/* 350 * Convert the path to a device 351 */ 352dev_t dm_get_dev_t(const char *path) 353{ 354 dev_t dev; 355 struct block_device *bdev; 356 357 bdev = lookup_bdev(path); 358 if (IS_ERR(bdev)) 359 dev = name_to_dev_t(path); 360 else { 361 dev = bdev->bd_dev; 362 bdput(bdev); 363 } 364 365 return dev; 366} 367EXPORT_SYMBOL_GPL(dm_get_dev_t); 368 369/* 370 * Add a device to the list, or just increment the usage count if 371 * it's already present. 372 */ 373int dm_get_device(struct dm_target *ti, const char *path, fmode_t mode, 374 struct dm_dev **result) 375{ 376 int r; 377 dev_t dev; 378 unsigned int major, minor; 379 char dummy; 380 struct dm_dev_internal *dd; 381 struct dm_table *t = ti->table; 382 383 BUG_ON(!t); 384 385 if (sscanf(path, "%u:%u%c", &major, &minor, &dummy) == 2) { 386 /* Extract the major/minor numbers */ 387 dev = MKDEV(major, minor); 388 if (MAJOR(dev) != major || MINOR(dev) != minor) 389 return -EOVERFLOW; 390 } else { 391 dev = dm_get_dev_t(path); 392 if (!dev) 393 return -ENODEV; 394 } 395 396 dd = find_device(&t->devices, dev); 397 if (!dd) { 398 dd = kmalloc(sizeof(*dd), GFP_KERNEL); 399 if (!dd) 400 return -ENOMEM; 401 402 if ((r = dm_get_table_device(t->md, dev, mode, &dd->dm_dev))) { 403 kfree(dd); 404 return r; 405 } 406 407 refcount_set(&dd->count, 1); 408 list_add(&dd->list, &t->devices); 409 goto out; 410 411 } else if (dd->dm_dev->mode != (mode | dd->dm_dev->mode)) { 412 r = upgrade_mode(dd, mode, t->md); 413 if (r) 414 return r; 415 } 416 refcount_inc(&dd->count); 417out: 418 *result = dd->dm_dev; 419 return 0; 420} 421EXPORT_SYMBOL(dm_get_device); 422 423static int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev, 424 sector_t start, sector_t len, void *data) 425{ 426 struct queue_limits *limits = data; 427 struct block_device *bdev = dev->bdev; 428 struct request_queue *q = bdev_get_queue(bdev); 429 char b[BDEVNAME_SIZE]; 430 431 if (unlikely(!q)) { 432 DMWARN("%s: Cannot set limits for nonexistent device %s", 433 dm_device_name(ti->table->md), bdevname(bdev, b)); 434 return 0; 435 } 436 437 if (blk_stack_limits(limits, &q->limits, 438 get_start_sect(bdev) + start) < 0) 439 DMWARN("%s: adding target device %s caused an alignment inconsistency: " 440 "physical_block_size=%u, logical_block_size=%u, " 441 "alignment_offset=%u, start=%llu", 442 dm_device_name(ti->table->md), bdevname(bdev, b), 443 q->limits.physical_block_size, 444 q->limits.logical_block_size, 445 q->limits.alignment_offset, 446 (unsigned long long) start << SECTOR_SHIFT); 447 return 0; 448} 449 450/* 451 * Decrement a device's use count and remove it if necessary. 452 */ 453void dm_put_device(struct dm_target *ti, struct dm_dev *d) 454{ 455 int found = 0; 456 struct list_head *devices = &ti->table->devices; 457 struct dm_dev_internal *dd; 458 459 list_for_each_entry(dd, devices, list) { 460 if (dd->dm_dev == d) { 461 found = 1; 462 break; 463 } 464 } 465 if (!found) { 466 DMWARN("%s: device %s not in table devices list", 467 dm_device_name(ti->table->md), d->name); 468 return; 469 } 470 if (refcount_dec_and_test(&dd->count)) { 471 dm_put_table_device(ti->table->md, d); 472 list_del(&dd->list); 473 kfree(dd); 474 } 475} 476EXPORT_SYMBOL(dm_put_device); 477 478/* 479 * Checks to see if the target joins onto the end of the table. 480 */ 481static int adjoin(struct dm_table *table, struct dm_target *ti) 482{ 483 struct dm_target *prev; 484 485 if (!table->num_targets) 486 return !ti->begin; 487 488 prev = &table->targets[table->num_targets - 1]; 489 return (ti->begin == (prev->begin + prev->len)); 490} 491 492/* 493 * Used to dynamically allocate the arg array. 494 * 495 * We do first allocation with GFP_NOIO because dm-mpath and dm-thin must 496 * process messages even if some device is suspended. These messages have a 497 * small fixed number of arguments. 498 * 499 * On the other hand, dm-switch needs to process bulk data using messages and 500 * excessive use of GFP_NOIO could cause trouble. 501 */ 502static char **realloc_argv(unsigned *size, char **old_argv) 503{ 504 char **argv; 505 unsigned new_size; 506 gfp_t gfp; 507 508 if (*size) { 509 new_size = *size * 2; 510 gfp = GFP_KERNEL; 511 } else { 512 new_size = 8; 513 gfp = GFP_NOIO; 514 } 515 argv = kmalloc_array(new_size, sizeof(*argv), gfp); 516 if (argv && old_argv) { 517 memcpy(argv, old_argv, *size * sizeof(*argv)); 518 *size = new_size; 519 } 520 521 kfree(old_argv); 522 return argv; 523} 524 525/* 526 * Destructively splits up the argument list to pass to ctr. 527 */ 528int dm_split_args(int *argc, char ***argvp, char *input) 529{ 530 char *start, *end = input, *out, **argv = NULL; 531 unsigned array_size = 0; 532 533 *argc = 0; 534 535 if (!input) { 536 *argvp = NULL; 537 return 0; 538 } 539 540 argv = realloc_argv(&array_size, argv); 541 if (!argv) 542 return -ENOMEM; 543 544 while (1) { 545 /* Skip whitespace */ 546 start = skip_spaces(end); 547 548 if (!*start) 549 break; /* success, we hit the end */ 550 551 /* 'out' is used to remove any back-quotes */ 552 end = out = start; 553 while (*end) { 554 /* Everything apart from '\0' can be quoted */ 555 if (*end == '\\' && *(end + 1)) { 556 *out++ = *(end + 1); 557 end += 2; 558 continue; 559 } 560 561 if (isspace(*end)) 562 break; /* end of token */ 563 564 *out++ = *end++; 565 } 566 567 /* have we already filled the array ? */ 568 if ((*argc + 1) > array_size) { 569 argv = realloc_argv(&array_size, argv); 570 if (!argv) 571 return -ENOMEM; 572 } 573 574 /* we know this is whitespace */ 575 if (*end) 576 end++; 577 578 /* terminate the string and put it in the array */ 579 *out = '\0'; 580 argv[*argc] = start; 581 (*argc)++; 582 } 583 584 *argvp = argv; 585 return 0; 586} 587 588/* 589 * Impose necessary and sufficient conditions on a devices's table such 590 * that any incoming bio which respects its logical_block_size can be 591 * processed successfully. If it falls across the boundary between 592 * two or more targets, the size of each piece it gets split into must 593 * be compatible with the logical_block_size of the target processing it. 594 */ 595static int validate_hardware_logical_block_alignment(struct dm_table *table, 596 struct queue_limits *limits) 597{ 598 /* 599 * This function uses arithmetic modulo the logical_block_size 600 * (in units of 512-byte sectors). 601 */ 602 unsigned short device_logical_block_size_sects = 603 limits->logical_block_size >> SECTOR_SHIFT; 604 605 /* 606 * Offset of the start of the next table entry, mod logical_block_size. 607 */ 608 unsigned short next_target_start = 0; 609 610 /* 611 * Given an aligned bio that extends beyond the end of a 612 * target, how many sectors must the next target handle? 613 */ 614 unsigned short remaining = 0; 615 616 struct dm_target *ti; 617 struct queue_limits ti_limits; 618 unsigned i; 619 620 /* 621 * Check each entry in the table in turn. 622 */ 623 for (i = 0; i < dm_table_get_num_targets(table); i++) { 624 ti = dm_table_get_target(table, i); 625 626 blk_set_stacking_limits(&ti_limits); 627 628 /* combine all target devices' limits */ 629 if (ti->type->iterate_devices) 630 ti->type->iterate_devices(ti, dm_set_device_limits, 631 &ti_limits); 632 633 /* 634 * If the remaining sectors fall entirely within this 635 * table entry are they compatible with its logical_block_size? 636 */ 637 if (remaining < ti->len && 638 remaining & ((ti_limits.logical_block_size >> 639 SECTOR_SHIFT) - 1)) 640 break; /* Error */ 641 642 next_target_start = 643 (unsigned short) ((next_target_start + ti->len) & 644 (device_logical_block_size_sects - 1)); 645 remaining = next_target_start ? 646 device_logical_block_size_sects - next_target_start : 0; 647 } 648 649 if (remaining) { 650 DMWARN("%s: table line %u (start sect %llu len %llu) " 651 "not aligned to h/w logical block size %u", 652 dm_device_name(table->md), i, 653 (unsigned long long) ti->begin, 654 (unsigned long long) ti->len, 655 limits->logical_block_size); 656 return -EINVAL; 657 } 658 659 return 0; 660} 661 662int dm_table_add_target(struct dm_table *t, const char *type, 663 sector_t start, sector_t len, char *params) 664{ 665 int r = -EINVAL, argc; 666 char **argv; 667 struct dm_target *tgt; 668 669 if (t->singleton) { 670 DMERR("%s: target type %s must appear alone in table", 671 dm_device_name(t->md), t->targets->type->name); 672 return -EINVAL; 673 } 674 675 BUG_ON(t->num_targets >= t->num_allocated); 676 677 tgt = t->targets + t->num_targets; 678 memset(tgt, 0, sizeof(*tgt)); 679 680 if (!len) { 681 DMERR("%s: zero-length target", dm_device_name(t->md)); 682 return -EINVAL; 683 } 684 685 tgt->type = dm_get_target_type(type); 686 if (!tgt->type) { 687 DMERR("%s: %s: unknown target type", dm_device_name(t->md), type); 688 return -EINVAL; 689 } 690 691 if (dm_target_needs_singleton(tgt->type)) { 692 if (t->num_targets) { 693 tgt->error = "singleton target type must appear alone in table"; 694 goto bad; 695 } 696 t->singleton = true; 697 } 698 699 if (dm_target_always_writeable(tgt->type) && !(t->mode & FMODE_WRITE)) { 700 tgt->error = "target type may not be included in a read-only table"; 701 goto bad; 702 } 703 704 if (t->immutable_target_type) { 705 if (t->immutable_target_type != tgt->type) { 706 tgt->error = "immutable target type cannot be mixed with other target types"; 707 goto bad; 708 } 709 } else if (dm_target_is_immutable(tgt->type)) { 710 if (t->num_targets) { 711 tgt->error = "immutable target type cannot be mixed with other target types"; 712 goto bad; 713 } 714 t->immutable_target_type = tgt->type; 715 } 716 717 if (dm_target_has_integrity(tgt->type)) 718 t->integrity_added = 1; 719 720 tgt->table = t; 721 tgt->begin = start; 722 tgt->len = len; 723 tgt->error = "Unknown error"; 724 725 /* 726 * Does this target adjoin the previous one ? 727 */ 728 if (!adjoin(t, tgt)) { 729 tgt->error = "Gap in table"; 730 goto bad; 731 } 732 733 r = dm_split_args(&argc, &argv, params); 734 if (r) { 735 tgt->error = "couldn't split parameters (insufficient memory)"; 736 goto bad; 737 } 738 739 r = tgt->type->ctr(tgt, argc, argv); 740 kfree(argv); 741 if (r) 742 goto bad; 743 744 t->highs[t->num_targets++] = tgt->begin + tgt->len - 1; 745 746 if (!tgt->num_discard_bios && tgt->discards_supported) 747 DMWARN("%s: %s: ignoring discards_supported because num_discard_bios is zero.", 748 dm_device_name(t->md), type); 749 750 return 0; 751 752 bad: 753 DMERR("%s: %s: %s", dm_device_name(t->md), type, tgt->error); 754 dm_put_target_type(tgt->type); 755 return r; 756} 757 758/* 759 * Target argument parsing helpers. 760 */ 761static int validate_next_arg(const struct dm_arg *arg, 762 struct dm_arg_set *arg_set, 763 unsigned *value, char **error, unsigned grouped) 764{ 765 const char *arg_str = dm_shift_arg(arg_set); 766 char dummy; 767 768 if (!arg_str || 769 (sscanf(arg_str, "%u%c", value, &dummy) != 1) || 770 (*value < arg->min) || 771 (*value > arg->max) || 772 (grouped && arg_set->argc < *value)) { 773 *error = arg->error; 774 return -EINVAL; 775 } 776 777 return 0; 778} 779 780int dm_read_arg(const struct dm_arg *arg, struct dm_arg_set *arg_set, 781 unsigned *value, char **error) 782{ 783 return validate_next_arg(arg, arg_set, value, error, 0); 784} 785EXPORT_SYMBOL(dm_read_arg); 786 787int dm_read_arg_group(const struct dm_arg *arg, struct dm_arg_set *arg_set, 788 unsigned *value, char **error) 789{ 790 return validate_next_arg(arg, arg_set, value, error, 1); 791} 792EXPORT_SYMBOL(dm_read_arg_group); 793 794const char *dm_shift_arg(struct dm_arg_set *as) 795{ 796 char *r; 797 798 if (as->argc) { 799 as->argc--; 800 r = *as->argv; 801 as->argv++; 802 return r; 803 } 804 805 return NULL; 806} 807EXPORT_SYMBOL(dm_shift_arg); 808 809void dm_consume_args(struct dm_arg_set *as, unsigned num_args) 810{ 811 BUG_ON(as->argc < num_args); 812 as->argc -= num_args; 813 as->argv += num_args; 814} 815EXPORT_SYMBOL(dm_consume_args); 816 817static bool __table_type_bio_based(enum dm_queue_mode table_type) 818{ 819 return (table_type == DM_TYPE_BIO_BASED || 820 table_type == DM_TYPE_DAX_BIO_BASED); 821} 822 823static bool __table_type_request_based(enum dm_queue_mode table_type) 824{ 825 return table_type == DM_TYPE_REQUEST_BASED; 826} 827 828void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type) 829{ 830 t->type = type; 831} 832EXPORT_SYMBOL_GPL(dm_table_set_type); 833 834/* validate the dax capability of the target device span */ 835int device_not_dax_capable(struct dm_target *ti, struct dm_dev *dev, 836 sector_t start, sector_t len, void *data) 837{ 838 int blocksize = *(int *) data, id; 839 bool rc; 840 841 id = dax_read_lock(); 842 rc = !dax_supported(dev->dax_dev, dev->bdev, blocksize, start, len); 843 dax_read_unlock(id); 844 845 return rc; 846} 847 848/* Check devices support synchronous DAX */ 849static int device_not_dax_synchronous_capable(struct dm_target *ti, struct dm_dev *dev, 850 sector_t start, sector_t len, void *data) 851{ 852 return !dev->dax_dev || !dax_synchronous(dev->dax_dev); 853} 854 855bool dm_table_supports_dax(struct dm_table *t, 856 iterate_devices_callout_fn iterate_fn, int *blocksize) 857{ 858 struct dm_target *ti; 859 unsigned i; 860 861 /* Ensure that all targets support DAX. */ 862 for (i = 0; i < dm_table_get_num_targets(t); i++) { 863 ti = dm_table_get_target(t, i); 864 865 if (!ti->type->direct_access) 866 return false; 867 868 if (!ti->type->iterate_devices || 869 ti->type->iterate_devices(ti, iterate_fn, blocksize)) 870 return false; 871 } 872 873 return true; 874} 875 876static int device_is_rq_stackable(struct dm_target *ti, struct dm_dev *dev, 877 sector_t start, sector_t len, void *data) 878{ 879 struct block_device *bdev = dev->bdev; 880 struct request_queue *q = bdev_get_queue(bdev); 881 882 /* request-based cannot stack on partitions! */ 883 if (bdev_is_partition(bdev)) 884 return false; 885 886 return queue_is_mq(q); 887} 888 889static int dm_table_determine_type(struct dm_table *t) 890{ 891 unsigned i; 892 unsigned bio_based = 0, request_based = 0, hybrid = 0; 893 struct dm_target *tgt; 894 struct list_head *devices = dm_table_get_devices(t); 895 enum dm_queue_mode live_md_type = dm_get_md_type(t->md); 896 int page_size = PAGE_SIZE; 897 898 if (t->type != DM_TYPE_NONE) { 899 /* target already set the table's type */ 900 if (t->type == DM_TYPE_BIO_BASED) { 901 /* possibly upgrade to a variant of bio-based */ 902 goto verify_bio_based; 903 } 904 BUG_ON(t->type == DM_TYPE_DAX_BIO_BASED); 905 goto verify_rq_based; 906 } 907 908 for (i = 0; i < t->num_targets; i++) { 909 tgt = t->targets + i; 910 if (dm_target_hybrid(tgt)) 911 hybrid = 1; 912 else if (dm_target_request_based(tgt)) 913 request_based = 1; 914 else 915 bio_based = 1; 916 917 if (bio_based && request_based) { 918 DMERR("Inconsistent table: different target types" 919 " can't be mixed up"); 920 return -EINVAL; 921 } 922 } 923 924 if (hybrid && !bio_based && !request_based) { 925 /* 926 * The targets can work either way. 927 * Determine the type from the live device. 928 * Default to bio-based if device is new. 929 */ 930 if (__table_type_request_based(live_md_type)) 931 request_based = 1; 932 else 933 bio_based = 1; 934 } 935 936 if (bio_based) { 937verify_bio_based: 938 /* We must use this table as bio-based */ 939 t->type = DM_TYPE_BIO_BASED; 940 if (dm_table_supports_dax(t, device_not_dax_capable, &page_size) || 941 (list_empty(devices) && live_md_type == DM_TYPE_DAX_BIO_BASED)) { 942 t->type = DM_TYPE_DAX_BIO_BASED; 943 } 944 return 0; 945 } 946 947 BUG_ON(!request_based); /* No targets in this table */ 948 949 t->type = DM_TYPE_REQUEST_BASED; 950 951verify_rq_based: 952 /* 953 * Request-based dm supports only tables that have a single target now. 954 * To support multiple targets, request splitting support is needed, 955 * and that needs lots of changes in the block-layer. 956 * (e.g. request completion process for partial completion.) 957 */ 958 if (t->num_targets > 1) { 959 DMERR("request-based DM doesn't support multiple targets"); 960 return -EINVAL; 961 } 962 963 if (list_empty(devices)) { 964 int srcu_idx; 965 struct dm_table *live_table = dm_get_live_table(t->md, &srcu_idx); 966 967 /* inherit live table's type */ 968 if (live_table) 969 t->type = live_table->type; 970 dm_put_live_table(t->md, srcu_idx); 971 return 0; 972 } 973 974 tgt = dm_table_get_immutable_target(t); 975 if (!tgt) { 976 DMERR("table load rejected: immutable target is required"); 977 return -EINVAL; 978 } else if (tgt->max_io_len) { 979 DMERR("table load rejected: immutable target that splits IO is not supported"); 980 return -EINVAL; 981 } 982 983 /* Non-request-stackable devices can't be used for request-based dm */ 984 if (!tgt->type->iterate_devices || 985 !tgt->type->iterate_devices(tgt, device_is_rq_stackable, NULL)) { 986 DMERR("table load rejected: including non-request-stackable devices"); 987 return -EINVAL; 988 } 989 990 return 0; 991} 992 993enum dm_queue_mode dm_table_get_type(struct dm_table *t) 994{ 995 return t->type; 996} 997 998struct target_type *dm_table_get_immutable_target_type(struct dm_table *t) 999{ 1000 return t->immutable_target_type; 1001} 1002 1003struct dm_target *dm_table_get_immutable_target(struct dm_table *t) 1004{ 1005 /* Immutable target is implicitly a singleton */ 1006 if (t->num_targets > 1 || 1007 !dm_target_is_immutable(t->targets[0].type)) 1008 return NULL; 1009 1010 return t->targets; 1011} 1012 1013struct dm_target *dm_table_get_wildcard_target(struct dm_table *t) 1014{ 1015 struct dm_target *ti; 1016 unsigned i; 1017 1018 for (i = 0; i < dm_table_get_num_targets(t); i++) { 1019 ti = dm_table_get_target(t, i); 1020 if (dm_target_is_wildcard(ti->type)) 1021 return ti; 1022 } 1023 1024 return NULL; 1025} 1026 1027bool dm_table_bio_based(struct dm_table *t) 1028{ 1029 return __table_type_bio_based(dm_table_get_type(t)); 1030} 1031 1032bool dm_table_request_based(struct dm_table *t) 1033{ 1034 return __table_type_request_based(dm_table_get_type(t)); 1035} 1036 1037static int dm_table_alloc_md_mempools(struct dm_table *t, struct mapped_device *md) 1038{ 1039 enum dm_queue_mode type = dm_table_get_type(t); 1040 unsigned per_io_data_size = 0; 1041 unsigned min_pool_size = 0; 1042 struct dm_target *ti; 1043 unsigned i; 1044 1045 if (unlikely(type == DM_TYPE_NONE)) { 1046 DMWARN("no table type is set, can't allocate mempools"); 1047 return -EINVAL; 1048 } 1049 1050 if (__table_type_bio_based(type)) 1051 for (i = 0; i < t->num_targets; i++) { 1052 ti = t->targets + i; 1053 per_io_data_size = max(per_io_data_size, ti->per_io_data_size); 1054 min_pool_size = max(min_pool_size, ti->num_flush_bios); 1055 } 1056 1057 t->mempools = dm_alloc_md_mempools(md, type, t->integrity_supported, 1058 per_io_data_size, min_pool_size); 1059 if (!t->mempools) 1060 return -ENOMEM; 1061 1062 return 0; 1063} 1064 1065void dm_table_free_md_mempools(struct dm_table *t) 1066{ 1067 dm_free_md_mempools(t->mempools); 1068 t->mempools = NULL; 1069} 1070 1071struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t) 1072{ 1073 return t->mempools; 1074} 1075 1076static int setup_indexes(struct dm_table *t) 1077{ 1078 int i; 1079 unsigned int total = 0; 1080 sector_t *indexes; 1081 1082 /* allocate the space for *all* the indexes */ 1083 for (i = t->depth - 2; i >= 0; i--) { 1084 t->counts[i] = dm_div_up(t->counts[i + 1], CHILDREN_PER_NODE); 1085 total += t->counts[i]; 1086 } 1087 1088 indexes = (sector_t *) dm_vcalloc(total, (unsigned long) NODE_SIZE); 1089 if (!indexes) 1090 return -ENOMEM; 1091 1092 /* set up internal nodes, bottom-up */ 1093 for (i = t->depth - 2; i >= 0; i--) { 1094 t->index[i] = indexes; 1095 indexes += (KEYS_PER_NODE * t->counts[i]); 1096 setup_btree_index(i, t); 1097 } 1098 1099 return 0; 1100} 1101 1102/* 1103 * Builds the btree to index the map. 1104 */ 1105static int dm_table_build_index(struct dm_table *t) 1106{ 1107 int r = 0; 1108 unsigned int leaf_nodes; 1109 1110 /* how many indexes will the btree have ? */ 1111 leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE); 1112 t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE); 1113 1114 /* leaf layer has already been set up */ 1115 t->counts[t->depth - 1] = leaf_nodes; 1116 t->index[t->depth - 1] = t->highs; 1117 1118 if (t->depth >= 2) 1119 r = setup_indexes(t); 1120 1121 return r; 1122} 1123 1124static bool integrity_profile_exists(struct gendisk *disk) 1125{ 1126 return !!blk_get_integrity(disk); 1127} 1128 1129/* 1130 * Get a disk whose integrity profile reflects the table's profile. 1131 * Returns NULL if integrity support was inconsistent or unavailable. 1132 */ 1133static struct gendisk * dm_table_get_integrity_disk(struct dm_table *t) 1134{ 1135 struct list_head *devices = dm_table_get_devices(t); 1136 struct dm_dev_internal *dd = NULL; 1137 struct gendisk *prev_disk = NULL, *template_disk = NULL; 1138 unsigned i; 1139 1140 for (i = 0; i < dm_table_get_num_targets(t); i++) { 1141 struct dm_target *ti = dm_table_get_target(t, i); 1142 if (!dm_target_passes_integrity(ti->type)) 1143 goto no_integrity; 1144 } 1145 1146 list_for_each_entry(dd, devices, list) { 1147 template_disk = dd->dm_dev->bdev->bd_disk; 1148 if (!integrity_profile_exists(template_disk)) 1149 goto no_integrity; 1150 else if (prev_disk && 1151 blk_integrity_compare(prev_disk, template_disk) < 0) 1152 goto no_integrity; 1153 prev_disk = template_disk; 1154 } 1155 1156 return template_disk; 1157 1158no_integrity: 1159 if (prev_disk) 1160 DMWARN("%s: integrity not set: %s and %s profile mismatch", 1161 dm_device_name(t->md), 1162 prev_disk->disk_name, 1163 template_disk->disk_name); 1164 return NULL; 1165} 1166 1167/* 1168 * Register the mapped device for blk_integrity support if the 1169 * underlying devices have an integrity profile. But all devices may 1170 * not have matching profiles (checking all devices isn't reliable 1171 * during table load because this table may use other DM device(s) which 1172 * must be resumed before they will have an initialized integity 1173 * profile). Consequently, stacked DM devices force a 2 stage integrity 1174 * profile validation: First pass during table load, final pass during 1175 * resume. 1176 */ 1177static int dm_table_register_integrity(struct dm_table *t) 1178{ 1179 struct mapped_device *md = t->md; 1180 struct gendisk *template_disk = NULL; 1181 1182 /* If target handles integrity itself do not register it here. */ 1183 if (t->integrity_added) 1184 return 0; 1185 1186 template_disk = dm_table_get_integrity_disk(t); 1187 if (!template_disk) 1188 return 0; 1189 1190 if (!integrity_profile_exists(dm_disk(md))) { 1191 t->integrity_supported = true; 1192 /* 1193 * Register integrity profile during table load; we can do 1194 * this because the final profile must match during resume. 1195 */ 1196 blk_integrity_register(dm_disk(md), 1197 blk_get_integrity(template_disk)); 1198 return 0; 1199 } 1200 1201 /* 1202 * If DM device already has an initialized integrity 1203 * profile the new profile should not conflict. 1204 */ 1205 if (blk_integrity_compare(dm_disk(md), template_disk) < 0) { 1206 DMWARN("%s: conflict with existing integrity profile: " 1207 "%s profile mismatch", 1208 dm_device_name(t->md), 1209 template_disk->disk_name); 1210 return 1; 1211 } 1212 1213 /* Preserve existing integrity profile */ 1214 t->integrity_supported = true; 1215 return 0; 1216} 1217 1218/* 1219 * Prepares the table for use by building the indices, 1220 * setting the type, and allocating mempools. 1221 */ 1222int dm_table_complete(struct dm_table *t) 1223{ 1224 int r; 1225 1226 r = dm_table_determine_type(t); 1227 if (r) { 1228 DMERR("unable to determine table type"); 1229 return r; 1230 } 1231 1232 r = dm_table_build_index(t); 1233 if (r) { 1234 DMERR("unable to build btrees"); 1235 return r; 1236 } 1237 1238 r = dm_table_register_integrity(t); 1239 if (r) { 1240 DMERR("could not register integrity profile."); 1241 return r; 1242 } 1243 1244 r = dm_table_alloc_md_mempools(t, t->md); 1245 if (r) 1246 DMERR("unable to allocate mempools"); 1247 1248 return r; 1249} 1250 1251static DEFINE_MUTEX(_event_lock); 1252void dm_table_event_callback(struct dm_table *t, 1253 void (*fn)(void *), void *context) 1254{ 1255 mutex_lock(&_event_lock); 1256 t->event_fn = fn; 1257 t->event_context = context; 1258 mutex_unlock(&_event_lock); 1259} 1260 1261void dm_table_event(struct dm_table *t) 1262{ 1263 mutex_lock(&_event_lock); 1264 if (t->event_fn) 1265 t->event_fn(t->event_context); 1266 mutex_unlock(&_event_lock); 1267} 1268EXPORT_SYMBOL(dm_table_event); 1269 1270inline sector_t dm_table_get_size(struct dm_table *t) 1271{ 1272 return t->num_targets ? (t->highs[t->num_targets - 1] + 1) : 0; 1273} 1274EXPORT_SYMBOL(dm_table_get_size); 1275 1276struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index) 1277{ 1278 if (index >= t->num_targets) 1279 return NULL; 1280 1281 return t->targets + index; 1282} 1283 1284/* 1285 * Search the btree for the correct target. 1286 * 1287 * Caller should check returned pointer for NULL 1288 * to trap I/O beyond end of device. 1289 */ 1290struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector) 1291{ 1292 unsigned int l, n = 0, k = 0; 1293 sector_t *node; 1294 1295 if (unlikely(sector >= dm_table_get_size(t))) 1296 return NULL; 1297 1298 for (l = 0; l < t->depth; l++) { 1299 n = get_child(n, k); 1300 node = get_node(t, l, n); 1301 1302 for (k = 0; k < KEYS_PER_NODE; k++) 1303 if (node[k] >= sector) 1304 break; 1305 } 1306 1307 return &t->targets[(KEYS_PER_NODE * n) + k]; 1308} 1309 1310/* 1311 * type->iterate_devices() should be called when the sanity check needs to 1312 * iterate and check all underlying data devices. iterate_devices() will 1313 * iterate all underlying data devices until it encounters a non-zero return 1314 * code, returned by whether the input iterate_devices_callout_fn, or 1315 * iterate_devices() itself internally. 1316 * 1317 * For some target type (e.g. dm-stripe), one call of iterate_devices() may 1318 * iterate multiple underlying devices internally, in which case a non-zero 1319 * return code returned by iterate_devices_callout_fn will stop the iteration 1320 * in advance. 1321 * 1322 * Cases requiring _any_ underlying device supporting some kind of attribute, 1323 * should use the iteration structure like dm_table_any_dev_attr(), or call 1324 * it directly. @func should handle semantics of positive examples, e.g. 1325 * capable of something. 1326 * 1327 * Cases requiring _all_ underlying devices supporting some kind of attribute, 1328 * should use the iteration structure like dm_table_supports_nowait() or 1329 * dm_table_supports_discards(). Or introduce dm_table_all_devs_attr() that 1330 * uses an @anti_func that handle semantics of counter examples, e.g. not 1331 * capable of something. So: return !dm_table_any_dev_attr(t, anti_func, data); 1332 */ 1333static bool dm_table_any_dev_attr(struct dm_table *t, 1334 iterate_devices_callout_fn func, void *data) 1335{ 1336 struct dm_target *ti; 1337 unsigned int i; 1338 1339 for (i = 0; i < dm_table_get_num_targets(t); i++) { 1340 ti = dm_table_get_target(t, i); 1341 1342 if (ti->type->iterate_devices && 1343 ti->type->iterate_devices(ti, func, data)) 1344 return true; 1345 } 1346 1347 return false; 1348} 1349 1350static int count_device(struct dm_target *ti, struct dm_dev *dev, 1351 sector_t start, sector_t len, void *data) 1352{ 1353 unsigned *num_devices = data; 1354 1355 (*num_devices)++; 1356 1357 return 0; 1358} 1359 1360/* 1361 * Check whether a table has no data devices attached using each 1362 * target's iterate_devices method. 1363 * Returns false if the result is unknown because a target doesn't 1364 * support iterate_devices. 1365 */ 1366bool dm_table_has_no_data_devices(struct dm_table *table) 1367{ 1368 struct dm_target *ti; 1369 unsigned i, num_devices; 1370 1371 for (i = 0; i < dm_table_get_num_targets(table); i++) { 1372 ti = dm_table_get_target(table, i); 1373 1374 if (!ti->type->iterate_devices) 1375 return false; 1376 1377 num_devices = 0; 1378 ti->type->iterate_devices(ti, count_device, &num_devices); 1379 if (num_devices) 1380 return false; 1381 } 1382 1383 return true; 1384} 1385 1386static int device_not_zoned_model(struct dm_target *ti, struct dm_dev *dev, 1387 sector_t start, sector_t len, void *data) 1388{ 1389 struct request_queue *q = bdev_get_queue(dev->bdev); 1390 enum blk_zoned_model *zoned_model = data; 1391 1392 return !q || blk_queue_zoned_model(q) != *zoned_model; 1393} 1394 1395/* 1396 * Check the device zoned model based on the target feature flag. If the target 1397 * has the DM_TARGET_ZONED_HM feature flag set, host-managed zoned devices are 1398 * also accepted but all devices must have the same zoned model. If the target 1399 * has the DM_TARGET_MIXED_ZONED_MODEL feature set, the devices can have any 1400 * zoned model with all zoned devices having the same zone size. 1401 */ 1402static bool dm_table_supports_zoned_model(struct dm_table *t, 1403 enum blk_zoned_model zoned_model) 1404{ 1405 struct dm_target *ti; 1406 unsigned i; 1407 1408 for (i = 0; i < dm_table_get_num_targets(t); i++) { 1409 ti = dm_table_get_target(t, i); 1410 1411 if (dm_target_supports_zoned_hm(ti->type)) { 1412 if (!ti->type->iterate_devices || 1413 ti->type->iterate_devices(ti, device_not_zoned_model, 1414 &zoned_model)) 1415 return false; 1416 } else if (!dm_target_supports_mixed_zoned_model(ti->type)) { 1417 if (zoned_model == BLK_ZONED_HM) 1418 return false; 1419 } 1420 } 1421 1422 return true; 1423} 1424 1425static int device_not_matches_zone_sectors(struct dm_target *ti, struct dm_dev *dev, 1426 sector_t start, sector_t len, void *data) 1427{ 1428 struct request_queue *q = bdev_get_queue(dev->bdev); 1429 unsigned int *zone_sectors = data; 1430 1431 if (!blk_queue_is_zoned(q)) 1432 return 0; 1433 1434 return !q || blk_queue_zone_sectors(q) != *zone_sectors; 1435} 1436 1437/* 1438 * Check consistency of zoned model and zone sectors across all targets. For 1439 * zone sectors, if the destination device is a zoned block device, it shall 1440 * have the specified zone_sectors. 1441 */ 1442static int validate_hardware_zoned_model(struct dm_table *table, 1443 enum blk_zoned_model zoned_model, 1444 unsigned int zone_sectors) 1445{ 1446 if (zoned_model == BLK_ZONED_NONE) 1447 return 0; 1448 1449 if (!dm_table_supports_zoned_model(table, zoned_model)) { 1450 DMERR("%s: zoned model is not consistent across all devices", 1451 dm_device_name(table->md)); 1452 return -EINVAL; 1453 } 1454 1455 /* Check zone size validity and compatibility */ 1456 if (!zone_sectors || !is_power_of_2(zone_sectors)) 1457 return -EINVAL; 1458 1459 if (dm_table_any_dev_attr(table, device_not_matches_zone_sectors, &zone_sectors)) { 1460 DMERR("%s: zone sectors is not consistent across all zoned devices", 1461 dm_device_name(table->md)); 1462 return -EINVAL; 1463 } 1464 1465 return 0; 1466} 1467 1468/* 1469 * Establish the new table's queue_limits and validate them. 1470 */ 1471int dm_calculate_queue_limits(struct dm_table *table, 1472 struct queue_limits *limits) 1473{ 1474 struct dm_target *ti; 1475 struct queue_limits ti_limits; 1476 unsigned i; 1477 enum blk_zoned_model zoned_model = BLK_ZONED_NONE; 1478 unsigned int zone_sectors = 0; 1479 1480 blk_set_stacking_limits(limits); 1481 1482 for (i = 0; i < dm_table_get_num_targets(table); i++) { 1483 blk_set_stacking_limits(&ti_limits); 1484 1485 ti = dm_table_get_target(table, i); 1486 1487 if (!ti->type->iterate_devices) 1488 goto combine_limits; 1489 1490 /* 1491 * Combine queue limits of all the devices this target uses. 1492 */ 1493 ti->type->iterate_devices(ti, dm_set_device_limits, 1494 &ti_limits); 1495 1496 if (zoned_model == BLK_ZONED_NONE && ti_limits.zoned != BLK_ZONED_NONE) { 1497 /* 1498 * After stacking all limits, validate all devices 1499 * in table support this zoned model and zone sectors. 1500 */ 1501 zoned_model = ti_limits.zoned; 1502 zone_sectors = ti_limits.chunk_sectors; 1503 } 1504 1505 /* Set I/O hints portion of queue limits */ 1506 if (ti->type->io_hints) 1507 ti->type->io_hints(ti, &ti_limits); 1508 1509 /* 1510 * Check each device area is consistent with the target's 1511 * overall queue limits. 1512 */ 1513 if (ti->type->iterate_devices(ti, device_area_is_invalid, 1514 &ti_limits)) 1515 return -EINVAL; 1516 1517combine_limits: 1518 /* 1519 * Merge this target's queue limits into the overall limits 1520 * for the table. 1521 */ 1522 if (blk_stack_limits(limits, &ti_limits, 0) < 0) 1523 DMWARN("%s: adding target device " 1524 "(start sect %llu len %llu) " 1525 "caused an alignment inconsistency", 1526 dm_device_name(table->md), 1527 (unsigned long long) ti->begin, 1528 (unsigned long long) ti->len); 1529 } 1530 1531 /* 1532 * Verify that the zoned model and zone sectors, as determined before 1533 * any .io_hints override, are the same across all devices in the table. 1534 * - this is especially relevant if .io_hints is emulating a disk-managed 1535 * zoned model (aka BLK_ZONED_NONE) on host-managed zoned block devices. 1536 * BUT... 1537 */ 1538 if (limits->zoned != BLK_ZONED_NONE) { 1539 /* 1540 * ...IF the above limits stacking determined a zoned model 1541 * validate that all of the table's devices conform to it. 1542 */ 1543 zoned_model = limits->zoned; 1544 zone_sectors = limits->chunk_sectors; 1545 } 1546 if (validate_hardware_zoned_model(table, zoned_model, zone_sectors)) 1547 return -EINVAL; 1548 1549 return validate_hardware_logical_block_alignment(table, limits); 1550} 1551 1552/* 1553 * Verify that all devices have an integrity profile that matches the 1554 * DM device's registered integrity profile. If the profiles don't 1555 * match then unregister the DM device's integrity profile. 1556 */ 1557static void dm_table_verify_integrity(struct dm_table *t) 1558{ 1559 struct gendisk *template_disk = NULL; 1560 1561 if (t->integrity_added) 1562 return; 1563 1564 if (t->integrity_supported) { 1565 /* 1566 * Verify that the original integrity profile 1567 * matches all the devices in this table. 1568 */ 1569 template_disk = dm_table_get_integrity_disk(t); 1570 if (template_disk && 1571 blk_integrity_compare(dm_disk(t->md), template_disk) >= 0) 1572 return; 1573 } 1574 1575 if (integrity_profile_exists(dm_disk(t->md))) { 1576 DMWARN("%s: unable to establish an integrity profile", 1577 dm_device_name(t->md)); 1578 blk_integrity_unregister(dm_disk(t->md)); 1579 } 1580} 1581 1582static int device_flush_capable(struct dm_target *ti, struct dm_dev *dev, 1583 sector_t start, sector_t len, void *data) 1584{ 1585 unsigned long flush = (unsigned long) data; 1586 struct request_queue *q = bdev_get_queue(dev->bdev); 1587 1588 return q && (q->queue_flags & flush); 1589} 1590 1591static bool dm_table_supports_flush(struct dm_table *t, unsigned long flush) 1592{ 1593 struct dm_target *ti; 1594 unsigned i; 1595 1596 /* 1597 * Require at least one underlying device to support flushes. 1598 * t->devices includes internal dm devices such as mirror logs 1599 * so we need to use iterate_devices here, which targets 1600 * supporting flushes must provide. 1601 */ 1602 for (i = 0; i < dm_table_get_num_targets(t); i++) { 1603 ti = dm_table_get_target(t, i); 1604 1605 if (!ti->num_flush_bios) 1606 continue; 1607 1608 if (ti->flush_supported) 1609 return true; 1610 1611 if (ti->type->iterate_devices && 1612 ti->type->iterate_devices(ti, device_flush_capable, (void *) flush)) 1613 return true; 1614 } 1615 1616 return false; 1617} 1618 1619static int device_dax_write_cache_enabled(struct dm_target *ti, 1620 struct dm_dev *dev, sector_t start, 1621 sector_t len, void *data) 1622{ 1623 struct dax_device *dax_dev = dev->dax_dev; 1624 1625 if (!dax_dev) 1626 return false; 1627 1628 if (dax_write_cache_enabled(dax_dev)) 1629 return true; 1630 return false; 1631} 1632 1633static int device_is_rotational(struct dm_target *ti, struct dm_dev *dev, 1634 sector_t start, sector_t len, void *data) 1635{ 1636 struct request_queue *q = bdev_get_queue(dev->bdev); 1637 1638 return q && !blk_queue_nonrot(q); 1639} 1640 1641static int device_is_not_random(struct dm_target *ti, struct dm_dev *dev, 1642 sector_t start, sector_t len, void *data) 1643{ 1644 struct request_queue *q = bdev_get_queue(dev->bdev); 1645 1646 return q && !blk_queue_add_random(q); 1647} 1648 1649static int device_not_write_same_capable(struct dm_target *ti, struct dm_dev *dev, 1650 sector_t start, sector_t len, void *data) 1651{ 1652 struct request_queue *q = bdev_get_queue(dev->bdev); 1653 1654 return q && !q->limits.max_write_same_sectors; 1655} 1656 1657static bool dm_table_supports_write_same(struct dm_table *t) 1658{ 1659 struct dm_target *ti; 1660 unsigned i; 1661 1662 for (i = 0; i < dm_table_get_num_targets(t); i++) { 1663 ti = dm_table_get_target(t, i); 1664 1665 if (!ti->num_write_same_bios) 1666 return false; 1667 1668 if (!ti->type->iterate_devices || 1669 ti->type->iterate_devices(ti, device_not_write_same_capable, NULL)) 1670 return false; 1671 } 1672 1673 return true; 1674} 1675 1676static int device_not_write_zeroes_capable(struct dm_target *ti, struct dm_dev *dev, 1677 sector_t start, sector_t len, void *data) 1678{ 1679 struct request_queue *q = bdev_get_queue(dev->bdev); 1680 1681 return q && !q->limits.max_write_zeroes_sectors; 1682} 1683 1684static bool dm_table_supports_write_zeroes(struct dm_table *t) 1685{ 1686 struct dm_target *ti; 1687 unsigned i = 0; 1688 1689 while (i < dm_table_get_num_targets(t)) { 1690 ti = dm_table_get_target(t, i++); 1691 1692 if (!ti->num_write_zeroes_bios) 1693 return false; 1694 1695 if (!ti->type->iterate_devices || 1696 ti->type->iterate_devices(ti, device_not_write_zeroes_capable, NULL)) 1697 return false; 1698 } 1699 1700 return true; 1701} 1702 1703static int device_not_nowait_capable(struct dm_target *ti, struct dm_dev *dev, 1704 sector_t start, sector_t len, void *data) 1705{ 1706 struct request_queue *q = bdev_get_queue(dev->bdev); 1707 1708 return q && !blk_queue_nowait(q); 1709} 1710 1711static bool dm_table_supports_nowait(struct dm_table *t) 1712{ 1713 struct dm_target *ti; 1714 unsigned i = 0; 1715 1716 while (i < dm_table_get_num_targets(t)) { 1717 ti = dm_table_get_target(t, i++); 1718 1719 if (!dm_target_supports_nowait(ti->type)) 1720 return false; 1721 1722 if (!ti->type->iterate_devices || 1723 ti->type->iterate_devices(ti, device_not_nowait_capable, NULL)) 1724 return false; 1725 } 1726 1727 return true; 1728} 1729 1730static int device_not_discard_capable(struct dm_target *ti, struct dm_dev *dev, 1731 sector_t start, sector_t len, void *data) 1732{ 1733 struct request_queue *q = bdev_get_queue(dev->bdev); 1734 1735 return q && !blk_queue_discard(q); 1736} 1737 1738static bool dm_table_supports_discards(struct dm_table *t) 1739{ 1740 struct dm_target *ti; 1741 unsigned i; 1742 1743 for (i = 0; i < dm_table_get_num_targets(t); i++) { 1744 ti = dm_table_get_target(t, i); 1745 1746 if (!ti->num_discard_bios) 1747 return false; 1748 1749 /* 1750 * Either the target provides discard support (as implied by setting 1751 * 'discards_supported') or it relies on _all_ data devices having 1752 * discard support. 1753 */ 1754 if (!ti->discards_supported && 1755 (!ti->type->iterate_devices || 1756 ti->type->iterate_devices(ti, device_not_discard_capable, NULL))) 1757 return false; 1758 } 1759 1760 return true; 1761} 1762 1763static int device_not_secure_erase_capable(struct dm_target *ti, 1764 struct dm_dev *dev, sector_t start, 1765 sector_t len, void *data) 1766{ 1767 struct request_queue *q = bdev_get_queue(dev->bdev); 1768 1769 return q && !blk_queue_secure_erase(q); 1770} 1771 1772static bool dm_table_supports_secure_erase(struct dm_table *t) 1773{ 1774 struct dm_target *ti; 1775 unsigned int i; 1776 1777 for (i = 0; i < dm_table_get_num_targets(t); i++) { 1778 ti = dm_table_get_target(t, i); 1779 1780 if (!ti->num_secure_erase_bios) 1781 return false; 1782 1783 if (!ti->type->iterate_devices || 1784 ti->type->iterate_devices(ti, device_not_secure_erase_capable, NULL)) 1785 return false; 1786 } 1787 1788 return true; 1789} 1790 1791static int device_requires_stable_pages(struct dm_target *ti, 1792 struct dm_dev *dev, sector_t start, 1793 sector_t len, void *data) 1794{ 1795 struct request_queue *q = bdev_get_queue(dev->bdev); 1796 1797 return q && blk_queue_stable_writes(q); 1798} 1799 1800void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q, 1801 struct queue_limits *limits) 1802{ 1803 bool wc = false, fua = false; 1804 int page_size = PAGE_SIZE; 1805 1806 /* 1807 * Copy table's limits to the DM device's request_queue 1808 */ 1809 q->limits = *limits; 1810 1811 if (dm_table_supports_nowait(t)) 1812 blk_queue_flag_set(QUEUE_FLAG_NOWAIT, q); 1813 else 1814 blk_queue_flag_clear(QUEUE_FLAG_NOWAIT, q); 1815 1816 if (!dm_table_supports_discards(t)) { 1817 blk_queue_flag_clear(QUEUE_FLAG_DISCARD, q); 1818 /* Must also clear discard limits... */ 1819 q->limits.max_discard_sectors = 0; 1820 q->limits.max_hw_discard_sectors = 0; 1821 q->limits.discard_granularity = 0; 1822 q->limits.discard_alignment = 0; 1823 q->limits.discard_misaligned = 0; 1824 } else 1825 blk_queue_flag_set(QUEUE_FLAG_DISCARD, q); 1826 1827 if (dm_table_supports_secure_erase(t)) 1828 blk_queue_flag_set(QUEUE_FLAG_SECERASE, q); 1829 1830 if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_WC))) { 1831 wc = true; 1832 if (dm_table_supports_flush(t, (1UL << QUEUE_FLAG_FUA))) 1833 fua = true; 1834 } 1835 blk_queue_write_cache(q, wc, fua); 1836 1837 if (dm_table_supports_dax(t, device_not_dax_capable, &page_size)) { 1838 blk_queue_flag_set(QUEUE_FLAG_DAX, q); 1839 if (dm_table_supports_dax(t, device_not_dax_synchronous_capable, NULL)) 1840 set_dax_synchronous(t->md->dax_dev); 1841 } 1842 else 1843 blk_queue_flag_clear(QUEUE_FLAG_DAX, q); 1844 1845 if (dm_table_any_dev_attr(t, device_dax_write_cache_enabled, NULL)) 1846 dax_write_cache(t->md->dax_dev, true); 1847 1848 /* Ensure that all underlying devices are non-rotational. */ 1849 if (dm_table_any_dev_attr(t, device_is_rotational, NULL)) 1850 blk_queue_flag_clear(QUEUE_FLAG_NONROT, q); 1851 else 1852 blk_queue_flag_set(QUEUE_FLAG_NONROT, q); 1853 1854 if (!dm_table_supports_write_same(t)) 1855 q->limits.max_write_same_sectors = 0; 1856 if (!dm_table_supports_write_zeroes(t)) 1857 q->limits.max_write_zeroes_sectors = 0; 1858 1859 dm_table_verify_integrity(t); 1860 1861 /* 1862 * Some devices don't use blk_integrity but still want stable pages 1863 * because they do their own checksumming. 1864 * If any underlying device requires stable pages, a table must require 1865 * them as well. Only targets that support iterate_devices are considered: 1866 * don't want error, zero, etc to require stable pages. 1867 */ 1868 if (dm_table_any_dev_attr(t, device_requires_stable_pages, NULL)) 1869 blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES, q); 1870 else 1871 blk_queue_flag_clear(QUEUE_FLAG_STABLE_WRITES, q); 1872 1873 /* 1874 * Determine whether or not this queue's I/O timings contribute 1875 * to the entropy pool, Only request-based targets use this. 1876 * Clear QUEUE_FLAG_ADD_RANDOM if any underlying device does not 1877 * have it set. 1878 */ 1879 if (blk_queue_add_random(q) && 1880 dm_table_any_dev_attr(t, device_is_not_random, NULL)) 1881 blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, q); 1882 1883 /* 1884 * For a zoned target, the number of zones should be updated for the 1885 * correct value to be exposed in sysfs queue/nr_zones. For a BIO based 1886 * target, this is all that is needed. 1887 */ 1888#ifdef CONFIG_BLK_DEV_ZONED 1889 if (blk_queue_is_zoned(q)) { 1890 WARN_ON_ONCE(queue_is_mq(q)); 1891 q->nr_zones = blkdev_nr_zones(t->md->disk); 1892 } 1893#endif 1894 1895 blk_queue_update_readahead(q); 1896} 1897 1898unsigned int dm_table_get_num_targets(struct dm_table *t) 1899{ 1900 return t->num_targets; 1901} 1902 1903struct list_head *dm_table_get_devices(struct dm_table *t) 1904{ 1905 return &t->devices; 1906} 1907 1908fmode_t dm_table_get_mode(struct dm_table *t) 1909{ 1910 return t->mode; 1911} 1912EXPORT_SYMBOL(dm_table_get_mode); 1913 1914enum suspend_mode { 1915 PRESUSPEND, 1916 PRESUSPEND_UNDO, 1917 POSTSUSPEND, 1918}; 1919 1920static void suspend_targets(struct dm_table *t, enum suspend_mode mode) 1921{ 1922 int i = t->num_targets; 1923 struct dm_target *ti = t->targets; 1924 1925 lockdep_assert_held(&t->md->suspend_lock); 1926 1927 while (i--) { 1928 switch (mode) { 1929 case PRESUSPEND: 1930 if (ti->type->presuspend) 1931 ti->type->presuspend(ti); 1932 break; 1933 case PRESUSPEND_UNDO: 1934 if (ti->type->presuspend_undo) 1935 ti->type->presuspend_undo(ti); 1936 break; 1937 case POSTSUSPEND: 1938 if (ti->type->postsuspend) 1939 ti->type->postsuspend(ti); 1940 break; 1941 } 1942 ti++; 1943 } 1944} 1945 1946void dm_table_presuspend_targets(struct dm_table *t) 1947{ 1948 if (!t) 1949 return; 1950 1951 suspend_targets(t, PRESUSPEND); 1952} 1953 1954void dm_table_presuspend_undo_targets(struct dm_table *t) 1955{ 1956 if (!t) 1957 return; 1958 1959 suspend_targets(t, PRESUSPEND_UNDO); 1960} 1961 1962void dm_table_postsuspend_targets(struct dm_table *t) 1963{ 1964 if (!t) 1965 return; 1966 1967 suspend_targets(t, POSTSUSPEND); 1968} 1969 1970int dm_table_resume_targets(struct dm_table *t) 1971{ 1972 int i, r = 0; 1973 1974 lockdep_assert_held(&t->md->suspend_lock); 1975 1976 for (i = 0; i < t->num_targets; i++) { 1977 struct dm_target *ti = t->targets + i; 1978 1979 if (!ti->type->preresume) 1980 continue; 1981 1982 r = ti->type->preresume(ti); 1983 if (r) { 1984 DMERR("%s: %s: preresume failed, error = %d", 1985 dm_device_name(t->md), ti->type->name, r); 1986 return r; 1987 } 1988 } 1989 1990 for (i = 0; i < t->num_targets; i++) { 1991 struct dm_target *ti = t->targets + i; 1992 1993 if (ti->type->resume) 1994 ti->type->resume(ti); 1995 } 1996 1997 return 0; 1998} 1999 2000struct mapped_device *dm_table_get_md(struct dm_table *t) 2001{ 2002 return t->md; 2003} 2004EXPORT_SYMBOL(dm_table_get_md); 2005 2006const char *dm_table_device_name(struct dm_table *t) 2007{ 2008 return dm_device_name(t->md); 2009} 2010EXPORT_SYMBOL_GPL(dm_table_device_name); 2011 2012void dm_table_run_md_queue_async(struct dm_table *t) 2013{ 2014 if (!dm_table_request_based(t)) 2015 return; 2016 2017 if (t->md->queue) 2018 blk_mq_run_hw_queues(t->md->queue, true); 2019} 2020EXPORT_SYMBOL(dm_table_run_md_queue_async); 2021 2022