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/slab.h>
  20 #include <linux/kmod.h>
  21 #include <linux/ctype.h>
  22 #include <linux/genhd.h>
  23 #include <linux/blktrace_api.h>
  24
  25 #include "check.h"
  26
  27 #include "acorn.h"
  28 #include "amiga.h"
  29 #include "atari.h"
  30 #include "ldm.h"
  31 #include "mac.h"
  32 #include "msdos.h"
  33 #include "osf.h"
  34 #include "sgi.h"
  35 #include "sun.h"
  36 #include "ibm.h"
  37 #include "ultrix.h"
  38 #include "efi.h"
  39 #include "karma.h"
  40 #include "sysv68.h"
  41
  42 #ifdef CONFIG_BLK_DEV_MD
  43 extern void md_autodetect_dev(dev_t dev);
  44 #endif
  45
  46 int warn_no_part = 1; /*This is ugly: should make genhd removable media aware*/
  47
  48 static int (*check_part[])(struct parsed_partitions *) = {
  49         /*
  50          * Probe partition formats with tables at disk address 0
  51          * that also have an ADFS boot block at 0xdc0.
  52          */
  53 #ifdef CONFIG_ACORN_PARTITION_ICS
  54         adfspart_check_ICS,
  55 #endif
  56 #ifdef CONFIG_ACORN_PARTITION_POWERTEC
  57         adfspart_check_POWERTEC,
  58 #endif
  59 #ifdef CONFIG_ACORN_PARTITION_EESOX
  60         adfspart_check_EESOX,
  61 #endif
  62
  63         /*
  64          * Now move on to formats that only have partition info at
  65          * disk address 0xdc0.  Since these may also have stale
  66          * PC/BIOS partition tables, they need to come before
  67          * the msdos entry.
  68          */
  69 #ifdef CONFIG_ACORN_PARTITION_CUMANA
  70         adfspart_check_CUMANA,
  71 #endif
  72 #ifdef CONFIG_ACORN_PARTITION_ADFS
  73         adfspart_check_ADFS,
  74 #endif
  75
  76 #ifdef CONFIG_EFI_PARTITION
  77         efi_partition,          /* this must come before msdos */
  78 #endif
  79 #ifdef CONFIG_SGI_PARTITION
  80         sgi_partition,
  81 #endif
  82 #ifdef CONFIG_LDM_PARTITION
  83         ldm_partition,          /* this must come before msdos */
  84 #endif
  85 #ifdef CONFIG_MSDOS_PARTITION
  86         msdos_partition,
  87 #endif
  88 #ifdef CONFIG_OSF_PARTITION
  89         osf_partition,
  90 #endif
  91 #ifdef CONFIG_SUN_PARTITION
  92         sun_partition,
  93 #endif
  94 #ifdef CONFIG_AMIGA_PARTITION
  95         amiga_partition,
  96 #endif
  97 #ifdef CONFIG_ATARI_PARTITION
  98         atari_partition,
  99 #endif
 100 #ifdef CONFIG_MAC_PARTITION
 101         mac_partition,
 102 #endif
 103 #ifdef CONFIG_ULTRIX_PARTITION
 104         ultrix_partition,
 105 #endif
 106 #ifdef CONFIG_IBM_PARTITION
 107         ibm_partition,
 108 #endif
 109 #ifdef CONFIG_KARMA_PARTITION
 110         karma_partition,
 111 #endif
 112 #ifdef CONFIG_SYSV68_PARTITION
 113         sysv68_partition,
 114 #endif
 115         NULL
 116 };
 117
 118 /*
 119  * disk_name() is used by partition check code and the genhd driver.
 120  * It formats the devicename of the indicated disk into
 121  * the supplied buffer (of size at least 32), and returns
 122  * a pointer to that same buffer (for convenience).
 123  */
 124
 125 char *disk_name(struct gendisk *hd, int partno, char *buf)
 126 {
 127         if (!partno)
 128                 snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name);
 129         else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1]))
 130                 snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, partno);
 131         else
 132                 snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno);
 133
 134         return buf;
 135 }
 136
 137 const char *bdevname(struct block_device *bdev, char *buf)
 138 {
 139         return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf);
 140 }
 141
 142 EXPORT_SYMBOL(bdevname);
 143
 144 /*
 145  * There's very little reason to use this, you should really
 146  * have a struct block_device just about everywhere and use
 147  * bdevname() instead.
 148  */
 149 const char *__bdevname(dev_t dev, char *buffer)
 150 {
 151         scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)",
 152                                 MAJOR(dev), MINOR(dev));
 153         return buffer;
 154 }
 155
 156 EXPORT_SYMBOL(__bdevname);
 157
 158 static struct parsed_partitions *
 159 check_partition(struct gendisk *hd, struct block_device *bdev)
 160 {
 161         struct parsed_partitions *state;
 162         int i, res, err;
 163
 164         state = kzalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
 165         if (!state)
 166                 return NULL;
 167         state->pp_buf = (char *)__get_free_page(GFP_KERNEL);
 168         if (!state->pp_buf) {
 169                 kfree(state);
 170                 return NULL;
 171         }
 172         state->pp_buf[0] = '\0';
 173
 174         state->bdev = bdev;
 175         disk_name(hd, 0, state->name);
 176         snprintf(state->pp_buf, PAGE_SIZE, " %s:", state->name);
 177         if (isdigit(state->name[strlen(state->name)-1]))
 178                 sprintf(state->name, "p");
 179
 180         state->limit = disk_max_parts(hd);
 181         i = res = err = 0;
 182         while (!res && check_part[i]) {
 183                 memset(&state->parts, 0, sizeof(state->parts));
 184                 res = check_part[i++](state);
 185                 if (res < 0) {
 186                         /* We have hit an I/O error which we don't report now.
 187                         * But record it, and let the others do their job.
 188                         */
 189                         err = res;
 190                         res = 0;
 191                 }
 192
 193         }
 194         if (res > 0) {
 195                 printk(KERN_INFO "%s", state->pp_buf);
 196
 197                 free_page((unsigned long)state->pp_buf);
 198                 return state;
 199         }
 200         if (state->access_beyond_eod)
 201                 err = -ENOSPC;
 202         if (err)
 203         /* The partition is unrecognized. So report I/O errors if there were any */
 204                 res = err;
 205         if (!res)
 206                 strlcat(state->pp_buf, " unknown partition table\n", PAGE_SIZE);
 207         else if (warn_no_part)
 208                 strlcat(state->pp_buf, " unable to read partition table\n", PAGE_SIZE);
 209
 210         printk(KERN_INFO "%s", state->pp_buf);
 211
 212         free_page((unsigned long)state->pp_buf);
 213         kfree(state);
 214         return ERR_PTR(res);
 215 }
 216
 217 static ssize_t part_partition_show(struct device *dev,
 218                                    struct device_attribute *attr, char *buf)
 219 {
 220         struct hd_struct *p = dev_to_part(dev);
 221
 222         return sprintf(buf, "%d\n", p->partno);
 223 }
 224
 225 static ssize_t part_start_show(struct device *dev,
 226                                struct device_attribute *attr, char *buf)
 227 {
 228         struct hd_struct *p = dev_to_part(dev);
 229
 230         return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect);
 231 }
 232
 233 ssize_t part_size_show(struct device *dev,
 234                        struct device_attribute *attr, char *buf)
 235 {
 236         struct hd_struct *p = dev_to_part(dev);
 237         return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects);
 238 }
 239
 240 ssize_t part_alignment_offset_show(struct device *dev,
 241                                    struct device_attribute *attr, char *buf)
 242 {
 243         struct hd_struct *p = dev_to_part(dev);
 244         return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset);
 245 }
 246
 247 ssize_t part_discard_alignment_show(struct device *dev,
 248                                    struct device_attribute *attr, char *buf)
 249 {
 250         struct hd_struct *p = dev_to_part(dev);
 251         return sprintf(buf, "%u\n", p->discard_alignment);
 252 }
 253
 254 ssize_t part_stat_show(struct device *dev,
 255                        struct device_attribute *attr, char *buf)
 256 {
 257         struct hd_struct *p = dev_to_part(dev);
 258         int cpu;
 259
 260         cpu = part_stat_lock();
 261         part_round_stats(cpu, p);
 262         part_stat_unlock();
 263         return sprintf(buf,
 264                 "%8lu %8lu %8llu %8u "
 265                 "%8lu %8lu %8llu %8u "
 266                 "%8u %8u %8u"
 267                 "\n",
 268                 part_stat_read(p, ios[READ]),
 269                 part_stat_read(p, merges[READ]),
 270                 (unsigned long long)part_stat_read(p, sectors[READ]),
 271                 jiffies_to_msecs(part_stat_read(p, ticks[READ])),
 272                 part_stat_read(p, ios[WRITE]),
 273                 part_stat_read(p, merges[WRITE]),
 274                 (unsigned long long)part_stat_read(p, sectors[WRITE]),
 275                 jiffies_to_msecs(part_stat_read(p, ticks[WRITE])),
 276                 part_in_flight(p),
 277                 jiffies_to_msecs(part_stat_read(p, io_ticks)),
 278                 jiffies_to_msecs(part_stat_read(p, time_in_queue)));
 279 }
 280
 281 ssize_t part_inflight_show(struct device *dev,
 282                         struct device_attribute *attr, char *buf)
 283 {
 284         struct hd_struct *p = dev_to_part(dev);
 285
 286         return sprintf(buf, "%8u %8u\n", p->in_flight[0], p->in_flight[1]);
 287 }
 288
 289 #ifdef CONFIG_FAIL_MAKE_REQUEST
 290 ssize_t part_fail_show(struct device *dev,
 291                        struct device_attribute *attr, char *buf)
 292 {
 293         struct hd_struct *p = dev_to_part(dev);
 294
 295         return sprintf(buf, "%d\n", p->make_it_fail);
 296 }
 297
 298 ssize_t part_fail_store(struct device *dev,
 299                         struct device_attribute *attr,
 300                         const char *buf, size_t count)
 301 {
 302         struct hd_struct *p = dev_to_part(dev);
 303         int i;
 304
 305         if (count > 0 && sscanf(buf, "%d", &i) > 0)
 306                 p->make_it_fail = (i == 0) ? 0 : 1;
 307
 308         return count;
 309 }
 310 #endif
 311
 312 static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL);
 313 static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL);
 314 static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
 315 static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL);
 316 static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show,
 317                    NULL);
 318 static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
 319 static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
 320 #ifdef CONFIG_FAIL_MAKE_REQUEST
 321 static struct device_attribute dev_attr_fail =
 322         __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
 323 #endif
 324
 325 static struct attribute *part_attrs[] = {
 326         &dev_attr_partition.attr,
 327         &dev_attr_start.attr,
 328         &dev_attr_size.attr,
 329         &dev_attr_alignment_offset.attr,
 330         &dev_attr_discard_alignment.attr,
 331         &dev_attr_stat.attr,
 332         &dev_attr_inflight.attr,
 333 #ifdef CONFIG_FAIL_MAKE_REQUEST
 334         &dev_attr_fail.attr,
 335 #endif
 336         NULL
 337 };
 338
 339 static struct attribute_group part_attr_group = {
 340         .attrs = part_attrs,
 341 };
 342
 343 static const struct attribute_group *part_attr_groups[] = {
 344         &part_attr_group,
 345 #ifdef CONFIG_BLK_DEV_IO_TRACE
 346         &blk_trace_attr_group,
 347 #endif
 348         NULL
 349 };
 350
 351 static void part_release(struct device *dev)
 352 {
 353         struct hd_struct *p = dev_to_part(dev);
 354         free_part_stats(p);
 355         free_part_info(p);
 356         kfree(p);
 357 }
 358
 359 struct device_type part_type = {
 360         .name           = "partition",
 361         .groups         = part_attr_groups,
 362         .release        = part_release,
 363 };
 364
 365 static void delete_partition_rcu_cb(struct rcu_head *head)
 366 {
 367         struct hd_struct *part = container_of(head, struct hd_struct, rcu_head);
 368         struct gendisk *disk = part_to_disk(part);
 369         struct request_queue *q = disk->queue;
 370         unsigned long flags;
 371
 372         part->start_sect = 0;
 373         part->nr_sects = 0;
 374         part_stat_set_all(part, 0);
 375         put_device(part_to_dev(part));
 376
 377         spin_lock_irqsave(q->queue_lock, flags);
 378         elv_quiesce_end(q);
 379         spin_unlock_irqrestore(q->queue_lock, flags);
 380 }
 381
 382 void delete_partition(struct gendisk *disk, int partno)
 383 {
 384         struct disk_part_tbl *ptbl = disk->part_tbl;
 385         struct hd_struct *part;
 386         struct request_queue *q = disk->queue;
 387
 388         if (partno >= ptbl->len)
 389                 return;
 390
 391         part = ptbl->part[partno];
 392         if (!part)
 393                 return;
 394
 395         blk_free_devt(part_devt(part));
 396         rcu_assign_pointer(ptbl->part[partno], NULL);
 397         rcu_assign_pointer(ptbl->last_lookup, NULL);
 398         kobject_put(part->holder_dir);
 399         device_del(part_to_dev(part));
 400
 401         spin_lock_irq(q->queue_lock);
 402         elv_quiesce_start(q);
 403         spin_unlock_irq(q->queue_lock);
 404
 405         call_rcu(&part->rcu_head, delete_partition_rcu_cb);
 406 }
 407
 408 static ssize_t whole_disk_show(struct device *dev,
 409                                struct device_attribute *attr, char *buf)
 410 {
 411         return 0;
 412 }
 413 static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH,
 414                    whole_disk_show, NULL);
 415
 416 struct hd_struct *add_partition(struct gendisk *disk, int partno,
 417                                 sector_t start, sector_t len, int flags,
 418                                 struct partition_meta_info *info)
 419 {
 420         struct hd_struct *p;
 421         dev_t devt = MKDEV(0, 0);
 422         struct device *ddev = disk_to_dev(disk);
 423         struct device *pdev;
 424         struct disk_part_tbl *ptbl;
 425         const char *dname;
 426         int err;
 427
 428         err = disk_expand_part_tbl(disk, partno);
 429         if (err)
 430                 return ERR_PTR(err);
 431         ptbl = disk->part_tbl;
 432
 433         if (ptbl->part[partno])
 434                 return ERR_PTR(-EBUSY);
 435
 436         p = kzalloc(sizeof(*p), GFP_KERNEL);
 437         if (!p)
 438                 return ERR_PTR(-EBUSY);
 439
 440         if (!init_part_stats(p)) {
 441                 err = -ENOMEM;
 442                 goto out_free;
 443         }
 444         pdev = part_to_dev(p);
 445
 446         p->start_sect = start;
 447         p->alignment_offset =
 448                 queue_limit_alignment_offset(&disk->queue->limits, start);
 449         p->discard_alignment =
 450                 queue_limit_discard_alignment(&disk->queue->limits, start);
 451         p->nr_sects = len;
 452         p->partno = partno;
 453         p->policy = get_disk_ro(disk);
 454
 455         if (info) {
 456                 struct partition_meta_info *pinfo = alloc_part_info(disk);
 457                 if (!pinfo)
 458                         goto out_free_stats;
 459                 memcpy(pinfo, info, sizeof(*info));
 460                 p->info = pinfo;
 461         }
 462
 463         dname = dev_name(ddev);
 464         if (isdigit(dname[strlen(dname) - 1]))
 465                 dev_set_name(pdev, "%sp%d", dname, partno);
 466         else
 467                 dev_set_name(pdev, "%s%d", dname, partno);
 468
 469         device_initialize(pdev);
 470         pdev->class = &block_class;
 471         pdev->type = &part_type;
 472         pdev->parent = ddev;
 473
 474         err = blk_alloc_devt(p, &devt);
 475         if (err)
 476                 goto out_free_info;
 477         pdev->devt = devt;
 478
 479         /* delay uevent until 'holders' subdir is created */
 480         dev_set_uevent_suppress(pdev, 1);
 481         err = device_add(pdev);
 482         if (err)
 483                 goto out_put;
 484
 485         err = -ENOMEM;
 486         p->holder_dir = kobject_create_and_add("holders", &pdev->kobj);
 487         if (!p->holder_dir)
 488                 goto out_del;
 489
 490         dev_set_uevent_suppress(pdev, 0);
 491         if (flags & ADDPART_FLAG_WHOLEDISK) {
 492                 err = device_create_file(pdev, &dev_attr_whole_disk);
 493                 if (err)
 494                         goto out_del;
 495         }
 496
 497         /* everything is up and running, commence */
 498         rcu_assign_pointer(ptbl->part[partno], p);
 499
 500         /* suppress uevent if the disk supresses it */
 501         if (!dev_get_uevent_suppress(ddev))
 502                 kobject_uevent(&pdev->kobj, KOBJ_ADD);
 503
 504         return p;
 505
 506 out_free_info:
 507         free_part_info(p);
 508 out_free_stats:
 509         free_part_stats(p);
 510 out_free:
 511         kfree(p);
 512         return ERR_PTR(err);
 513 out_del:
 514         kobject_put(p->holder_dir);
 515         device_del(pdev);
 516 out_put:
 517         put_device(pdev);
 518         blk_free_devt(devt);
 519         return ERR_PTR(err);
 520 }
 521
 522 /* Not exported, helper to add_disk(). */
 523 void register_disk(struct gendisk *disk)
 524 {
 525         struct device *ddev = disk_to_dev(disk);
 526         struct block_device *bdev;
 527         struct disk_part_iter piter;
 528         struct hd_struct *part;
 529         int err;
 530
 531         ddev->parent = disk->driverfs_dev;
 532
 533         dev_set_name(ddev, disk->disk_name);
 534
 535         /* delay uevents, until we scanned partition table */
 536         dev_set_uevent_suppress(ddev, 1);
 537
 538         if (device_add(ddev))
 539                 return;
 540 #ifndef CONFIG_SYSFS_DEPRECATED
 541         err = sysfs_create_link(block_depr, &ddev->kobj,
 542                                 kobject_name(&ddev->kobj));
 543         if (err) {
 544                 device_del(ddev);
 545                 return;
 546         }
 547 #endif
 548         disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
 549         disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
 550
 551         /* No minors to use for partitions */
 552         if (!disk_partitionable(disk))
 553                 goto exit;
 554
 555         /* No such device (e.g., media were just removed) */
 556         if (!get_capacity(disk))
 557                 goto exit;
 558
 559         bdev = bdget_disk(disk, 0);
 560         if (!bdev)
 561                 goto exit;
 562
 563         bdev->bd_invalidated = 1;
 564         err = blkdev_get(bdev, FMODE_READ);
 565         if (err < 0)
 566                 goto exit;
 567         blkdev_put(bdev, FMODE_READ);
 568
 569 exit:
 570         /* announce disk after possible partitions are created */
 571         dev_set_uevent_suppress(ddev, 0);
 572         kobject_uevent(&ddev->kobj, KOBJ_ADD);
 573
 574         /* announce possible partitions */
 575         disk_part_iter_init(&piter, disk, 0);
 576         while ((part = disk_part_iter_next(&piter)))
 577                 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
 578         disk_part_iter_exit(&piter);
 579 }
 580
 581 static bool disk_unlock_native_capacity(struct gendisk *disk)
 582 {
 583         const struct block_device_operations *bdops = disk->fops;
 584
 585         if (bdops->unlock_native_capacity &&
 586             !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) {
 587                 printk(KERN_CONT "enabling native capacity\n");
 588                 bdops->unlock_native_capacity(disk);
 589                 disk->flags |= GENHD_FL_NATIVE_CAPACITY;
 590                 return true;
 591         } else {
 592                 printk(KERN_CONT "truncated\n");
 593                 return false;
 594         }
 595 }
 596
 597 int rescan_partitions(struct gendisk *disk, struct block_device *bdev)
 598 {
 599         struct parsed_partitions *state = NULL;
 600         struct disk_part_iter piter;
 601         struct hd_struct *part;
 602         int p, highest, res;
 603 rescan:
 604         if (state && !IS_ERR(state)) {
 605                 kfree(state);
 606                 state = NULL;
 607         }
 608
 609         if (bdev->bd_part_count)
 610                 return -EBUSY;
 611         res = invalidate_partition(disk, 0);
 612         if (res)
 613                 return res;
 614
 615         disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
 616         while ((part = disk_part_iter_next(&piter)))
 617                 delete_partition(disk, part->partno);
 618         disk_part_iter_exit(&piter);
 619
 620         if (disk->fops->revalidate_disk)
 621                 disk->fops->revalidate_disk(disk);
 622         check_disk_size_change(disk, bdev);
 623         bdev->bd_invalidated = 0;
 624         if (!get_capacity(disk) || !(state = check_partition(disk, bdev)))
 625                 return 0;
 626         if (IS_ERR(state)) {
 627                 /*
 628                  * I/O error reading the partition table.  If any
 629                  * partition code tried to read beyond EOD, retry
 630                  * after unlocking native capacity.
 631                  */
 632                 if (PTR_ERR(state) == -ENOSPC) {
 633                         printk(KERN_WARNING "%s: partition table beyond EOD, ",
 634                                disk->disk_name);
 635                         if (disk_unlock_native_capacity(disk))
 636                                 goto rescan;
 637                 }
 638                 return -EIO;
 639         }
 640         /*
 641          * If any partition code tried to read beyond EOD, try
 642          * unlocking native capacity even if partition table is
 643          * sucessfully read as we could be missing some partitions.
 644          */
 645         if (state->access_beyond_eod) {
 646                 printk(KERN_WARNING
 647                        "%s: partition table partially beyond EOD, ",
 648                        disk->disk_name);
 649                 if (disk_unlock_native_capacity(disk))
 650                         goto rescan;
 651         }
 652
 653         /* tell userspace that the media / partition table may have changed */
 654         kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
 655
 656         /* Detect the highest partition number and preallocate
 657          * disk->part_tbl.  This is an optimization and not strictly
 658          * necessary.
 659          */
 660         for (p = 1, highest = 0; p < state->limit; p++)
 661                 if (state->parts[p].size)
 662                         highest = p;
 663
 664         disk_expand_part_tbl(disk, highest);
 665
 666         /* add partitions */
 667         for (p = 1; p < state->limit; p++) {
 668                 sector_t size, from;
 669                 struct partition_meta_info *info = NULL;
 670
 671                 size = state->parts[p].size;
 672                 if (!size)
 673                         continue;
 674
 675                 from = state->parts[p].from;
 676                 if (from >= get_capacity(disk)) {
 677                         printk(KERN_WARNING
 678                                "%s: p%d start %llu is beyond EOD, ",
 679                                disk->disk_name, p, (unsigned long long) from);
 680                         if (disk_unlock_native_capacity(disk))
 681                                 goto rescan;
 682                         continue;
 683                 }
 684
 685                 if (from + size > get_capacity(disk)) {
 686                         printk(KERN_WARNING
 687                                "%s: p%d size %llu extends beyond EOD, ",
 688                                disk->disk_name, p, (unsigned long long) size);
 689
 690                         if (disk_unlock_native_capacity(disk)) {
 691                                 /* free state and restart */
 692                                 goto rescan;
 693                         } else {
 694                                 /*
 695                                  * we can not ignore partitions of broken tables
 696                                  * created by for example camera firmware, but
 697                                  * we limit them to the end of the disk to avoid
 698                                  * creating invalid block devices
 699                                  */
 700                                 size = get_capacity(disk) - from;
 701                         }
 702                 }
 703
 704                 if (state->parts[p].has_info)
 705                         info = &state->parts[p].info;
 706                 part = add_partition(disk, p, from, size,
 707                                      state->parts[p].flags,
 708                                      &state->parts[p].info);
 709                 if (IS_ERR(part)) {
 710                         printk(KERN_ERR " %s: p%d could not be added: %ld\n",
 711                                disk->disk_name, p, -PTR_ERR(part));
 712                         continue;
 713                 }
 714 #ifdef CONFIG_BLK_DEV_MD
 715                 if (state->parts[p].flags & ADDPART_FLAG_RAID)
 716                         md_autodetect_dev(part_to_dev(part)->devt);
 717 #endif
 718         }
 719         kfree(state);
 720         return 0;
 721 }
 722
 723 unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p)
 724 {
 725         struct address_space *mapping = bdev->bd_inode->i_mapping;
 726         struct page *page;
 727
 728         page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)),
 729                                  NULL);
 730         if (!IS_ERR(page)) {
 731                 if (PageError(page))
 732                         goto fail;
 733                 p->v = page;
 734                 return (unsigned char *)page_address(page) +  ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9);
 735 fail:
 736                 page_cache_release(page);
 737         }
 738         p->v = NULL;
 739         return NULL;
 740 }
 741
 742 EXPORT_SYMBOL(read_dev_sector);
 743
 744 void del_gendisk(struct gendisk *disk)
 745 {
 746         struct disk_part_iter piter;
 747         struct hd_struct *part;
 748
 749         /* invalidate stuff */
 750         disk_part_iter_init(&piter, disk,
 751                              DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
 752         while ((part = disk_part_iter_next(&piter))) {
 753                 invalidate_partition(disk, part->partno);
 754                 delete_partition(disk, part->partno);
 755         }
 756         disk_part_iter_exit(&piter);
 757
 758         invalidate_partition(disk, 0);
 759         blk_free_devt(disk_to_dev(disk)->devt);
 760         set_capacity(disk, 0);
 761         disk->flags &= ~GENHD_FL_UP;
 762         unlink_gendisk(disk);
 763         part_stat_set_all(&disk->part0, 0);
 764         disk->part0.stamp = 0;
 765
 766         kobject_put(disk->part0.holder_dir);
 767         kobject_put(disk->slave_dir);
 768         disk->driverfs_dev = NULL;
 769 #ifndef CONFIG_SYSFS_DEPRECATED
 770         sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
 771 #endif
 772         device_del(disk_to_dev(disk));
 773 }