drivers/md/dm-table.c

   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  */
  34 static 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  */
  49 static 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  */
  57 static 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  */
  67 static 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  */
  82 static 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
  97 void *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 }
 113 EXPORT_SYMBOL(dm_vcalloc);
 114
 115 /*
 116  * highs, and targets are managed as dynamic arrays during a
 117  * table load.
 118  */
 119 static 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
 144 int 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
 181 static 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
 195 void 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  */
 229 static 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  */
 243 static 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  */
 330 static 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  */
 352 dev_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 }
 367 EXPORT_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  */
 373 int 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);
 417 out:
 418         *result = dd->dm_dev;
 419         return 0;
 420 }
 421 EXPORT_SYMBOL(dm_get_device);
 422
 423 static 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  */
 453 void 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 }
 476 EXPORT_SYMBOL(dm_put_device);
 477
 478 /*
 479  * Checks to see if the target joins onto the end of the table.
 480  */
 481 static 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  */
 502 static 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  */
 528 int 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  */
 595 static 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
 662 int 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  */
 761 static 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
 780 int 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 }
 785 EXPORT_SYMBOL(dm_read_arg);
 786
 787 int 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 }
 792 EXPORT_SYMBOL(dm_read_arg_group);
 793
 794 const 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 }
 807 EXPORT_SYMBOL(dm_shift_arg);
 808
 809 void 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 }
 815 EXPORT_SYMBOL(dm_consume_args);
 816
 817 static 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
 823 static bool __table_type_request_based(enum dm_queue_mode table_type)
 824 {
 825         return table_type == DM_TYPE_REQUEST_BASED;
 826 }
 827
 828 void dm_table_set_type(struct dm_table *t, enum dm_queue_mode type)
 829 {
 830         t->type = type;
 831 }
 832 EXPORT_SYMBOL_GPL(dm_table_set_type);
 833
 834 /* validate the dax capability of the target device span */
 835 int 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 */
 849 static 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
 855 bool 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
 876 static 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
 889 static 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) {
 937 verify_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
 951 verify_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
 993 enum dm_queue_mode dm_table_get_type(struct dm_table *t)
 994 {
 995         return t->type;
 996 }
 997
 998 struct target_type *dm_table_get_immutable_target_type(struct dm_table *t)
 999 {
1000         return t->immutable_target_type;
1001 }
1002
1003 struct 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
1013 struct 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
1027 bool dm_table_bio_based(struct dm_table *t)
1028 {
1029         return __table_type_bio_based(dm_table_get_type(t));
1030 }
1031
1032 bool dm_table_request_based(struct dm_table *t)
1033 {
1034         return __table_type_request_based(dm_table_get_type(t));
1035 }
1036
1037 static 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
1065 void dm_table_free_md_mempools(struct dm_table *t)
1066 {
1067         dm_free_md_mempools(t->mempools);
1068         t->mempools = NULL;
1069 }
1070
1071 struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
1072 {
1073         return t->mempools;
1074 }
1075
1076 static 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  */
1105 static 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
1124 static 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  */
1133 static 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
1158 no_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  */
1177 static 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  */
1222 int 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
1251 static DEFINE_MUTEX(_event_lock);
1252 void 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
1261 void 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 }
1268 EXPORT_SYMBOL(dm_table_event);
1269
1270 inline 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 }
1274 EXPORT_SYMBOL(dm_table_get_size);
1275
1276 struct 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  */
1290 struct 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  */
1333 static 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
1350 static 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  */
1366 bool 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
1386 static 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  */
1402 static 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
1425 static 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  */
1442 static 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  */
1471 int 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
1517 combine_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  */
1557 static 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
1582 static 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
1591 static 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
1619 static 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
1633 static 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
1641 static 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
1649 static 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
1657 static 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
1676 static 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
1684 static 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
1703 static 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
1711 static 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
1730 static 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
1738 static 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
1763 static 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
1772 static 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
1791 static 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
1800 void 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
1898 unsigned int dm_table_get_num_targets(struct dm_table *t)
1899 {
1900         return t->num_targets;
1901 }
1902
1903 struct list_head *dm_table_get_devices(struct dm_table *t)
1904 {
1905         return &t->devices;
1906 }
1907
1908 fmode_t dm_table_get_mode(struct dm_table *t)
1909 {
1910         return t->mode;
1911 }
1912 EXPORT_SYMBOL(dm_table_get_mode);
1913
1914 enum suspend_mode {
1915         PRESUSPEND,
1916         PRESUSPEND_UNDO,
1917         POSTSUSPEND,
1918 };
1919
1920 static 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
1946 void dm_table_presuspend_targets(struct dm_table *t)
1947 {
1948         if (!t)
1949                 return;
1950
1951         suspend_targets(t, PRESUSPEND);
1952 }
1953
1954 void dm_table_presuspend_undo_targets(struct dm_table *t)
1955 {
1956         if (!t)
1957                 return;
1958
1959         suspend_targets(t, PRESUSPEND_UNDO);
1960 }
1961
1962 void dm_table_postsuspend_targets(struct dm_table *t)
1963 {
1964         if (!t)
1965                 return;
1966
1967         suspend_targets(t, POSTSUSPEND);
1968 }
1969
1970 int 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
2000 struct mapped_device *dm_table_get_md(struct dm_table *t)
2001 {
2002         return t->md;
2003 }
2004 EXPORT_SYMBOL(dm_table_get_md);
2005
2006 const char *dm_table_device_name(struct dm_table *t)
2007 {
2008         return dm_device_name(t->md);
2009 }
2010 EXPORT_SYMBOL_GPL(dm_table_device_name);
2011
2012 void 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 }
2020 EXPORT_SYMBOL(dm_table_run_md_queue_async);
2021