fs/partitions/check.c

   1 /*
   2  *  fs/partitions/check.c
   3  *
   4  *  Code extracted from drivers/block/genhd.c
   5  *  Copyright (C) 1991-1998  Linus Torvalds
   6  *  Re-organised Feb 1998 Russell King
   7  *
   8  *  We now have independent partition support from the
   9  *  block drivers, which allows all the partition code to
  10  *  be grouped in one location, and it to be mostly self
  11  *  contained.
  12  *
  13  *  Added needed MAJORS for new pairs, {hdi,hdj}, {hdk,hdl}
  14  */
  15
  16 #include <linux/init.h>
  17 #include <linux/module.h>
  18 #include <linux/fs.h>
  19 #include <linux/kmod.h>
  20 #include <linux/ctype.h>
  21 #include <linux/genhd.h>
  22 #include <linux/blktrace_api.h>
  23
  24 #include "check.h"
  25
  26 #include "acorn.h"
  27 #include "amiga.h"
  28 #include "atari.h"
  29 #include "ldm.h"
  30 #include "mac.h"
  31 #include "msdos.h"
  32 #include "osf.h"
  33 #include "sgi.h"
  34 #include "sun.h"
  35 #include "ibm.h"
  36 #include "ultrix.h"
  37 #include "efi.h"
  38 #include "karma.h"
  39 #include "sysv68.h"
  40
  41 #ifdef CONFIG_BLK_DEV_MD
  42 extern void md_autodetect_dev(dev_t dev);
  43 #endif
  44
  45 int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
  46
  47 static int (*check_part[])(struct parsed_partitions *, struct block_device *) = {
  48         /*
  49          * Probe partition formats with tables at disk address 0
  50          * that also have an ADFS boot block at 0xdc0.
  51          */
  52 #ifdef CONFIG_ACORN_PARTITION_ICS
  53         adfspart_check_ICS,
  54 #endif
  55 #ifdef CONFIG_ACORN_PARTITION_POWERTEC
  56         adfspart_check_POWERTEC,
  57 #endif
  58 #ifdef CONFIG_ACORN_PARTITION_EESOX
  59         adfspart_check_EESOX,
  60 #endif
  61
  62         /*
  63          * Now move on to formats that only have partition info at
  64          * disk address 0xdc0.  Since these may also have stale
  65          * PC/BIOS partition tables, they need to come before
  66          * the msdos entry.
  67          */
  68 #ifdef CONFIG_ACORN_PARTITION_CUMANA
  69         adfspart_check_CUMANA,
  70 #endif
  71 #ifdef CONFIG_ACORN_PARTITION_ADFS
  72         adfspart_check_ADFS,
  73 #endif
  74
  75 #ifdef CONFIG_EFI_PARTITION
  76         efi_partition,          /* this must come before msdos */
  77 #endif
  78 #ifdef CONFIG_SGI_PARTITION
  79         sgi_partition,
  80 #endif
  81 #ifdef CONFIG_LDM_PARTITION
  82         ldm_partition,          /* this must come before msdos */
  83 #endif
  84 #ifdef CONFIG_MSDOS_PARTITION
  85         msdos_partition,
  86 #endif
  87 #ifdef CONFIG_OSF_PARTITION
  88         osf_partition,
  89 #endif
  90 #ifdef CONFIG_SUN_PARTITION
  91         sun_partition,
  92 #endif
  93 #ifdef CONFIG_AMIGA_PARTITION
  94         amiga_partition,
  95 #endif
  96 #ifdef CONFIG_ATARI_PARTITION
  97         atari_partition,
  98 #endif
  99 #ifdef CONFIG_MAC_PARTITION
 100         mac_partition,
 101 #endif
 102 #ifdef CONFIG_ULTRIX_PARTITION
 103         ultrix_partition,
 104 #endif
 105 #ifdef CONFIG_IBM_PARTITION
 106         ibm_partition,
 107 #endif
 108 #ifdef CONFIG_KARMA_PARTITION
 109         karma_partition,
 110 #endif
 111 #ifdef CONFIG_SYSV68_PARTITION
 112         sysv68_partition,
 113 #endif
 114         NULL
 115 };
 116
 117 /*
 118  * disk_name() is used by partition check code and the genhd driver.
 119  * It formats the devicename of the indicated disk into
 120  * the supplied buffer (of size at least 32), and returns
 121  * a pointer to that same buffer (for convenience).
 122  */
 123
 124 char *disk_name(struct gendisk *hd, int partno, char *buf)
 125 {
 126         if (!partno)
 127                 snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
 128         else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
 129                 snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, partno);
 130         else
 131                 snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno);
 132
 133         return buf;
 134 }
 135
 136 const char *bdevname(struct block_device *bdev, char *buf)
 137 {
 138         return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
 139 }
 140
 141 EXPORT_SYMBOL(bdevname);
 142
 143 /*
 144  * There's very little reason to use this, you should really
 145  * have a struct block_device just about everywhere and use
 146  * bdevname() instead.
 147  */
 148 const char *__bdevname(dev_t dev, char *buffer)
 149 {
 150         scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
 151                                 MAJOR(dev), MINOR(dev));
 152         return buffer;
 153 }
 154
 155 EXPORT_SYMBOL(__bdevname);
 156
 157 static struct parsed_partitions *
 158 check_partition(struct gendisk *hd, struct block_device *bdev)
 159 {
 160         struct parsed_partitions *state;
 161         int i, res, err;
 162
 163         state = kmalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
 164         if (!state)
 165                 return NULL;
 166
 167         disk_name(hd, 0, state->name);
 168         printk(KERN_INFO " %s:", state->name);
 169         if (isdigit(state->name[strlen(state->name)-1]))
 170                 sprintf(state->name, "p");
 171
 172         state->limit = disk_max_parts(hd);
 173         i = res = err = 0;
 174         while (!res && check_part[i]) {
 175                 memset(&state->parts, 0, sizeof(state->parts));
 176                 res = check_part[i++](state, bdev);
 177                 if (res < 0) {
 178                         /* We have hit an I/O error which we don't report now.
 179                         * But record it, and let the others do their job.
 180                         */
 181                         err = res;
 182                         res = 0;
 183                 }
 184
 185         }
 186         if (res > 0)
 187                 return state;
 188         if (err)
 189         /* The partition is unrecognized. So report I/O errors if there were any */
 190                 res = err;
 191         if (!res)
 192                 printk(" unknown partition table\n");
 193         else if (warn_no_part)
 194                 printk(" unable to read partition table\n");
 195         kfree(state);
 196         return ERR_PTR(res);
 197 }
 198
 199 static ssize_t part_partition_show(struct device *dev,
 200                                    struct device_attribute *attr, char *buf)
 201 {
 202         struct hd_struct *p = dev_to_part(dev);
 203
 204         return sprintf(buf, "%d\n", p->partno);
 205 }
 206
 207 static ssize_t part_start_show(struct device *dev,
 208                                struct device_attribute *attr, char *buf)
 209 {
 210         struct hd_struct *p = dev_to_part(dev);
 211
 212         return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
 213 }
 214
 215 ssize_t part_size_show(struct device *dev,
 216                        struct device_attribute *attr, char *buf)
 217 {
 218         struct hd_struct *p = dev_to_part(dev);
 219         return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
 220 }
 221
 222 ssize_t part_alignment_offset_show(struct device *dev,
 223                                    struct device_attribute *attr, char *buf)
 224 {
 225         struct hd_struct *p = dev_to_part(dev);
 226         return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
 227 }
 228
 229 ssize_t part_discard_alignment_show(struct device *dev,
 230                                    struct device_attribute *attr, char *buf)
 231 {
 232         struct hd_struct *p = dev_to_part(dev);
 233         return sprintf(buf, "%u\n", p->discard_alignment);
 234 }
 235
 236 ssize_t part_stat_show(struct device *dev,
 237                        struct device_attribute *attr, char *buf)
 238 {
 239         struct hd_struct *p = dev_to_part(dev);
 240         int cpu;
 241
 242         cpu = part_stat_lock();
 243         part_round_stats(cpu, p);
 244         part_stat_unlock();
 245         return sprintf(buf,
 246                 "%8lu %8lu %8llu %8u "
 247                 "%8lu %8lu %8llu %8u "
 248                 "%8u %8u %8u"
 249                 "\n",
 250                 part_stat_read(p, ios[READ]),
 251                 part_stat_read(p, merges[READ]),
 252                 (unsigned long long)part_stat_read(p, sectors[READ]),
 253                 jiffies_to_msecs(part_stat_read(p, ticks[READ])),
 254                 part_stat_read(p, ios[WRITE]),
 255                 part_stat_read(p, merges[WRITE]),
 256                 (unsigned long long)part_stat_read(p, sectors[WRITE]),
 257                 jiffies_to_msecs(part_stat_read(p, ticks[WRITE])),
 258                 part_in_flight(p),
 259                 jiffies_to_msecs(part_stat_read(p, io_ticks)),
 260                 jiffies_to_msecs(part_stat_read(p, time_in_queue)));
 261 }
 262
 263 ssize_t part_inflight_show(struct device *dev,
 264                         struct device_attribute *attr, char *buf)
 265 {
 266         struct hd_struct *p = dev_to_part(dev);
 267
 268         return sprintf(buf, "%8u %8u\n", p->in_flight[0], p->in_flight[1]);
 269 }
 270
 271 #ifdef CONFIG_FAIL_MAKE_REQUEST
 272 ssize_t part_fail_show(struct device *dev,
 273                        struct device_attribute *attr, char *buf)
 274 {
 275         struct hd_struct *p = dev_to_part(dev);
 276
 277         return sprintf(buf, "%d\n", p->make_it_fail);
 278 }
 279
 280 ssize_t part_fail_store(struct device *dev,
 281                         struct device_attribute *attr,
 282                         const char *buf, size_t count)
 283 {
 284         struct hd_struct *p = dev_to_part(dev);
 285         int i;
 286
 287         if (count > 0 && sscanf(buf, "%d", &i) > 0)
 288                 p->make_it_fail = (i == 0) ? 0 : 1;
 289
 290         return count;
 291 }
 292 #endif
 293
 294 static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
 295 static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
 296 static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
 297 static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
 298 static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
 299                    NULL);
 300 static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
 301 static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
 302 #ifdef CONFIG_FAIL_MAKE_REQUEST
 303 static struct device_attribute dev_attr_fail =
 304         __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
 305 #endif
 306
 307 static struct attribute *part_attrs[] = {
 308         &dev_attr_partition.attr,
 309         &dev_attr_start.attr,
 310         &dev_attr_size.attr,
 311         &dev_attr_alignment_offset.attr,
 312         &dev_attr_discard_alignment.attr,
 313         &dev_attr_stat.attr,
 314         &dev_attr_inflight.attr,
 315 #ifdef CONFIG_FAIL_MAKE_REQUEST
 316         &dev_attr_fail.attr,
 317 #endif
 318         NULL
 319 };
 320
 321 static struct attribute_group part_attr_group = {
 322         .attrs = part_attrs,
 323 };
 324
 325 static const struct attribute_group *part_attr_groups[] = {
 326         &part_attr_group,
 327 #ifdef CONFIG_BLK_DEV_IO_TRACE
 328         &blk_trace_attr_group,
 329 #endif
 330         NULL
 331 };
 332
 333 static void part_release(struct device *dev)
 334 {
 335         struct hd_struct *p = dev_to_part(dev);
 336         free_part_stats(p);
 337         kfree(p);
 338 }
 339
 340 struct device_type part_type = {
 341         .name           = "partition",
 342         .groups         = part_attr_groups,
 343         .release        = part_release,
 344 };
 345
 346 static void delete_partition_rcu_cb(struct rcu_head *head)
 347 {
 348         struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
 349
 350         part->start_sect = 0;
 351         part->nr_sects = 0;
 352         part_stat_set_all(part, 0);
 353         put_device(part_to_dev(part));
 354 }
 355
 356 void delete_partition(struct gendisk *disk, int partno)
 357 {
 358         struct disk_part_tbl *ptbl = disk->part_tbl;
 359         struct hd_struct *part;
 360
 361         if (partno >= ptbl->len)
 362                 return;
 363
 364         part = ptbl->part[partno];
 365         if (!part)
 366                 return;
 367
 368         blk_free_devt(part_devt(part));
 369         rcu_assign_pointer(ptbl->part[partno], NULL);
 370         rcu_assign_pointer(ptbl->last_lookup, NULL);
 371         kobject_put(part->holder_dir);
 372         device_del(part_to_dev(part));
 373
 374         call_rcu(&part->rcu_head, delete_partition_rcu_cb);
 375 }
 376
 377 static ssize_t whole_disk_show(struct device *dev,
 378                                struct device_attribute *attr, char *buf)
 379 {
 380         return 0;
 381 }
 382 static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
 383                    whole_disk_show, NULL);
 384
 385 struct hd_struct *add_partition(struct gendisk *disk, int partno,
 386                                 sector_t start, sector_t len, int flags)
 387 {
 388         struct hd_struct *p;
 389         dev_t devt = MKDEV(0, 0);
 390         struct device *ddev = disk_to_dev(disk);
 391         struct device *pdev;
 392         struct disk_part_tbl *ptbl;
 393         const char *dname;
 394         int err;
 395
 396         err = disk_expand_part_tbl(disk, partno);
 397         if (err)
 398                 return ERR_PTR(err);
 399         ptbl = disk->part_tbl;
 400
 401         if (ptbl->part[partno])
 402                 return ERR_PTR(-EBUSY);
 403
 404         p = kzalloc(sizeof(*p), GFP_KERNEL);
 405         if (!p)
 406                 return ERR_PTR(-EBUSY);
 407
 408         if (!init_part_stats(p)) {
 409                 err = -ENOMEM;
 410                 goto out_free;
 411         }
 412         pdev = part_to_dev(p);
 413
 414         p->start_sect = start;
 415         p->alignment_offset = queue_sector_alignment_offset(disk->queue, start);
 416         p->discard_alignment = queue_sector_discard_alignment(disk->queue,
 417                                                               start);
 418         p->nr_sects = len;
 419         p->partno = partno;
 420         p->policy = get_disk_ro(disk);
 421
 422         dname = dev_name(ddev);
 423         if (isdigit(dname[strlen(dname) - 1]))
 424                 dev_set_name(pdev, "%sp%d", dname, partno);
 425         else
 426                 dev_set_name(pdev, "%s%d", dname, partno);
 427
 428         device_initialize(pdev);
 429         pdev->class = &block_class;
 430         pdev->type = &part_type;
 431         pdev->parent = ddev;
 432
 433         err = blk_alloc_devt(p, &devt);
 434         if (err)
 435                 goto out_free_stats;
 436         pdev->devt = devt;
 437
 438         /* delay uevent until 'holders' subdir is created */
 439         dev_set_uevent_suppress(pdev, 1);
 440         err = device_add(pdev);
 441         if (err)
 442                 goto out_put;
 443
 444         err = -ENOMEM;
 445         p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
 446         if (!p->holder_dir)
 447                 goto out_del;
 448
 449         dev_set_uevent_suppress(pdev, 0);
 450         if (flags & ADDPART_FLAG_WHOLEDISK) {
 451                 err = device_create_file(pdev, &dev_attr_whole_disk);
 452                 if (err)
 453                         goto out_del;
 454         }
 455
 456         /* everything is up and running, commence */
 457         INIT_RCU_HEAD(&p->rcu_head);
 458         rcu_assign_pointer(ptbl->part[partno], p);
 459
 460         /* suppress uevent if the disk supresses it */
 461         if (!dev_get_uevent_suppress(ddev))
 462                 kobject_uevent(&pdev->kobj, KOBJ_ADD);
 463
 464         return p;
 465
 466 out_free_stats:
 467         free_part_stats(p);
 468 out_free:
 469         kfree(p);
 470         return ERR_PTR(err);
 471 out_del:
 472         kobject_put(p->holder_dir);
 473         device_del(pdev);
 474 out_put:
 475         put_device(pdev);
 476         blk_free_devt(devt);
 477         return ERR_PTR(err);
 478 }
 479
 480 /* Not exported, helper to add_disk(). */
 481 void register_disk(struct gendisk *disk)
 482 {
 483         struct device *ddev = disk_to_dev(disk);
 484         struct block_device *bdev;
 485         struct disk_part_iter piter;
 486         struct hd_struct *part;
 487         int err;
 488
 489         ddev->parent = disk->driverfs_dev;
 490
 491         dev_set_name(ddev, disk->disk_name);
 492
 493         /* delay uevents, until we scanned partition table */
 494         dev_set_uevent_suppress(ddev, 1);
 495
 496         if (device_add(ddev))
 497                 return;
 498 #ifndef CONFIG_SYSFS_DEPRECATED
 499         err = sysfs_create_link(block_depr, &ddev->kobj,
 500                                 kobject_name(&ddev->kobj));
 501         if (err) {
 502                 device_del(ddev);
 503                 return;
 504         }
 505 #endif
 506         disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
 507         disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
 508
 509         /* No minors to use for partitions */
 510         if (!disk_partitionable(disk))
 511                 goto exit;
 512
 513         /* No such device (e.g., media were just removed) */
 514         if (!get_capacity(disk))
 515                 goto exit;
 516
 517         bdev = bdget_disk(disk, 0);
 518         if (!bdev)
 519                 goto exit;
 520
 521         bdev->bd_invalidated = 1;
 522         err = blkdev_get(bdev, FMODE_READ);
 523         if (err < 0)
 524                 goto exit;
 525         blkdev_put(bdev, FMODE_READ);
 526
 527 exit:
 528         /* announce disk after possible partitions are created */
 529         dev_set_uevent_suppress(ddev, 0);
 530         kobject_uevent(&ddev->kobj, KOBJ_ADD);
 531
 532         /* announce possible partitions */
 533         disk_part_iter_init(&piter, disk, 0);
 534         while ((part = disk_part_iter_next(&piter)))
 535                 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
 536         disk_part_iter_exit(&piter);
 537 }
 538
 539 int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
 540 {
 541         struct disk_part_iter piter;
 542         struct hd_struct *part;
 543         struct parsed_partitions *state;
 544         int p, highest, res;
 545
 546         if (bdev->bd_part_count)
 547                 return -EBUSY;
 548         res = invalidate_partition(disk, 0);
 549         if (res)
 550                 return res;
 551
 552         disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
 553         while ((part = disk_part_iter_next(&piter)))
 554                 delete_partition(disk, part->partno);
 555         disk_part_iter_exit(&piter);
 556
 557         if (disk->fops->revalidate_disk)
 558                 disk->fops->revalidate_disk(disk);
 559         check_disk_size_change(disk, bdev);
 560         bdev->bd_invalidated = 0;
 561         if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
 562                 return 0;
 563         if (IS_ERR(state))      /* I/O error reading the partition table */
 564                 return -EIO;
 565
 566         /* tell userspace that the media / partition table may have changed */
 567         kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
 568
 569         /* Detect the highest partition number and preallocate
 570          * disk->part_tbl.  This is an optimization and not strictly
 571          * necessary.
 572          */
 573         for (p = 1, highest = 0; p < state->limit; p++)
 574                 if (state->parts[p].size)
 575                         highest = p;
 576
 577         disk_expand_part_tbl(disk, highest);
 578
 579         /* add partitions */
 580         for (p = 1; p < state->limit; p++) {
 581                 sector_t size, from;
 582 try_scan:
 583                 size = state->parts[p].size;
 584                 if (!size)
 585                         continue;
 586
 587                 from = state->parts[p].from;
 588                 if (from >= get_capacity(disk)) {
 589                         printk(KERN_WARNING
 590                                "%s: p%d ignored, start %llu is behind the end of the disk\n",
 591                                disk->disk_name, p, (unsigned long long) from);
 592                         continue;
 593                 }
 594
 595                 if (from + size > get_capacity(disk)) {
 596                         const struct block_device_operations *bdops = disk->fops;
 597                         unsigned long long capacity;
 598
 599                         printk(KERN_WARNING
 600                                "%s: p%d size %llu exceeds device capacity, ",
 601                                disk->disk_name, p, (unsigned long long) size);
 602
 603                         if (bdops->set_capacity &&
 604                             (disk->flags & GENHD_FL_NATIVE_CAPACITY) == 0) {
 605                                 printk(KERN_CONT "enabling native capacity\n");
 606                                 capacity = bdops->set_capacity(disk, ~0ULL);
 607                                 disk->flags |= GENHD_FL_NATIVE_CAPACITY;
 608                                 if (capacity > get_capacity(disk)) {
 609                                         set_capacity(disk, capacity);
 610                                         check_disk_size_change(disk, bdev);
 611                                         bdev->bd_invalidated = 0;
 612                                 }
 613                                 goto try_scan;
 614                         } else {
 615                                 /*
 616                                  * we can not ignore partitions of broken tables
 617                                  * created by for example camera firmware, but
 618                                  * we limit them to the end of the disk to avoid
 619                                  * creating invalid block devices
 620                                  */
 621                                 printk(KERN_CONT "limited to end of disk\n");
 622                                 size = get_capacity(disk) - from;
 623                         }
 624                 }
 625                 part = add_partition(disk, p, from, size,
 626                                      state->parts[p].flags);
 627                 if (IS_ERR(part)) {
 628                         printk(KERN_ERR " %s: p%d could not be added: %ld\n",
 629                                disk->disk_name, p, -PTR_ERR(part));
 630                         continue;
 631                 }
 632 #ifdef CONFIG_BLK_DEV_MD
 633                 if (state->parts[p].flags & ADDPART_FLAG_RAID)
 634                         md_autodetect_dev(part_to_dev(part)->devt);
 635 #endif
 636         }
 637         kfree(state);
 638         return 0;
 639 }
 640
 641 unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
 642 {
 643         struct address_space *mapping = bdev->bd_inode->i_mapping;
 644         struct page *page;
 645
 646         page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
 647                                  NULL);
 648         if (!IS_ERR(page)) {
 649                 if (PageError(page))
 650                         goto fail;
 651                 p->v = page;
 652                 return (unsigned char *)page_address(page) +  ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
 653 fail:
 654                 page_cache_release(page);
 655         }
 656         p->v = NULL;
 657         return NULL;
 658 }
 659
 660 EXPORT_SYMBOL(read_dev_sector);
 661
 662 void del_gendisk(struct gendisk *disk)
 663 {
 664         struct disk_part_iter piter;
 665         struct hd_struct *part;
 666
 667         /* invalidate stuff */
 668         disk_part_iter_init(&piter, disk,
 669                              DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
 670         while ((part = disk_part_iter_next(&piter))) {
 671                 invalidate_partition(disk, part->partno);
 672                 delete_partition(disk, part->partno);
 673         }
 674         disk_part_iter_exit(&piter);
 675
 676         invalidate_partition(disk, 0);
 677         blk_free_devt(disk_to_dev(disk)->devt);
 678         set_capacity(disk, 0);
 679         disk->flags &= ~GENHD_FL_UP;
 680         unlink_gendisk(disk);
 681         part_stat_set_all(&disk->part0, 0);
 682         disk->part0.stamp = 0;
 683
 684         kobject_put(disk->part0.holder_dir);
 685         kobject_put(disk->slave_dir);
 686         disk->driverfs_dev = NULL;
 687 #ifndef CONFIG_SYSFS_DEPRECATED
 688         sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
 689 #endif
 690         device_del(disk_to_dev(disk));
 691 }