block/genhd.c

   1 /*
   2  *  gendisk handling
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/fs.h>
   7 #include <linux/genhd.h>
   8 #include <linux/kdev_t.h>
   9 #include <linux/kernel.h>
  10 #include <linux/blkdev.h>
  11 #include <linux/init.h>
  12 #include <linux/spinlock.h>
  13 #include <linux/seq_file.h>
  14 #include <linux/slab.h>
  15 #include <linux/kmod.h>
  16 #include <linux/kobj_map.h>
  17 #include <linux/buffer_head.h>
  18 #include <linux/mutex.h>
  19
  20 struct kset block_subsys;
  21 static DEFINE_MUTEX(block_subsys_lock);
  22
  23 /*
  24  * Can be deleted altogether. Later.
  25  *
  26  */
  27 static struct blk_major_name {
  28         struct blk_major_name *next;
  29         int major;
  30         char name[16];
  31 } *major_names[BLKDEV_MAJOR_HASH_SIZE];
  32
  33 /* index in the above - for now: assume no multimajor ranges */
  34 static inline int major_to_index(int major)
  35 {
  36         return major % BLKDEV_MAJOR_HASH_SIZE;
  37 }
  38
  39 #ifdef CONFIG_PROC_FS
  40
  41 void blkdev_show(struct seq_file *f, off_t offset)
  42 {
  43         struct blk_major_name *dp;
  44
  45         if (offset < BLKDEV_MAJOR_HASH_SIZE) {
  46                 mutex_lock(&block_subsys_lock);
  47                 for (dp = major_names[offset]; dp; dp = dp->next)
  48                         seq_printf(f, "%3d %s\n", dp->major, dp->name);
  49                 mutex_unlock(&block_subsys_lock);
  50         }
  51 }
  52
  53 #endif /* CONFIG_PROC_FS */
  54
  55 int register_blkdev(unsigned int major, const char *name)
  56 {
  57         struct blk_major_name **n, *p;
  58         int index, ret = 0;
  59
  60         mutex_lock(&block_subsys_lock);
  61
  62         /* temporary */
  63         if (major == 0) {
  64                 for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
  65                         if (major_names[index] == NULL)
  66                                 break;
  67                 }
  68
  69                 if (index == 0) {
  70                         printk("register_blkdev: failed to get major for %s\n",
  71                                name);
  72                         ret = -EBUSY;
  73                         goto out;
  74                 }
  75                 major = index;
  76                 ret = major;
  77         }
  78
  79         p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
  80         if (p == NULL) {
  81                 ret = -ENOMEM;
  82                 goto out;
  83         }
  84
  85         p->major = major;
  86         strlcpy(p->name, name, sizeof(p->name));
  87         p->next = NULL;
  88         index = major_to_index(major);
  89
  90         for (n = &major_names[index]; *n; n = &(*n)->next) {
  91                 if ((*n)->major == major)
  92                         break;
  93         }
  94         if (!*n)
  95                 *n = p;
  96         else
  97                 ret = -EBUSY;
  98
  99         if (ret < 0) {
 100                 printk("register_blkdev: cannot get major %d for %s\n",
 101                        major, name);
 102                 kfree(p);
 103         }
 104 out:
 105         mutex_unlock(&block_subsys_lock);
 106         return ret;
 107 }
 108
 109 EXPORT_SYMBOL(register_blkdev);
 110
 111 /* todo: make void - error printk here */
 112 int unregister_blkdev(unsigned int major, const char *name)
 113 {
 114         struct blk_major_name **n;
 115         struct blk_major_name *p = NULL;
 116         int index = major_to_index(major);
 117         int ret = 0;
 118
 119         mutex_lock(&block_subsys_lock);
 120         for (n = &major_names[index]; *n; n = &(*n)->next)
 121                 if ((*n)->major == major)
 122                         break;
 123         if (!*n || strcmp((*n)->name, name))
 124                 ret = -EINVAL;
 125         else {
 126                 p = *n;
 127                 *n = p->next;
 128         }
 129         mutex_unlock(&block_subsys_lock);
 130         kfree(p);
 131
 132         return ret;
 133 }
 134
 135 EXPORT_SYMBOL(unregister_blkdev);
 136
 137 static struct kobj_map *bdev_map;
 138
 139 /*
 140  * Register device numbers dev..(dev+range-1)
 141  * range must be nonzero
 142  * The hash chain is sorted on range, so that subranges can override.
 143  */
 144 void blk_register_region(dev_t dev, unsigned long range, struct module *module,
 145                          struct kobject *(*probe)(dev_t, int *, void *),
 146                          int (*lock)(dev_t, void *), void *data)
 147 {
 148         kobj_map(bdev_map, dev, range, module, probe, lock, data);
 149 }
 150
 151 EXPORT_SYMBOL(blk_register_region);
 152
 153 void blk_unregister_region(dev_t dev, unsigned long range)
 154 {
 155         kobj_unmap(bdev_map, dev, range);
 156 }
 157
 158 EXPORT_SYMBOL(blk_unregister_region);
 159
 160 static struct kobject *exact_match(dev_t dev, int *part, void *data)
 161 {
 162         struct gendisk *p = data;
 163         return &p->kobj;
 164 }
 165
 166 static int exact_lock(dev_t dev, void *data)
 167 {
 168         struct gendisk *p = data;
 169
 170         if (!get_disk(p))
 171                 return -1;
 172         return 0;
 173 }
 174
 175 /**
 176  * add_disk - add partitioning information to kernel list
 177  * @disk: per-device partitioning information
 178  *
 179  * This function registers the partitioning information in @disk
 180  * with the kernel.
 181  */
 182 void add_disk(struct gendisk *disk)
 183 {
 184         disk->flags |= GENHD_FL_UP;
 185         blk_register_region(MKDEV(disk->major, disk->first_minor),
 186                             disk->minors, NULL, exact_match, exact_lock, disk);
 187         register_disk(disk);
 188         blk_register_queue(disk);
 189 }
 190
 191 EXPORT_SYMBOL(add_disk);
 192 EXPORT_SYMBOL(del_gendisk);     /* in partitions/check.c */
 193
 194 void unlink_gendisk(struct gendisk *disk)
 195 {
 196         blk_unregister_queue(disk);
 197         blk_unregister_region(MKDEV(disk->major, disk->first_minor),
 198                               disk->minors);
 199 }
 200
 201 #define to_disk(obj) container_of(obj,struct gendisk,kobj)
 202
 203 /**
 204  * get_gendisk - get partitioning information for a given device
 205  * @dev: device to get partitioning information for
 206  *
 207  * This function gets the structure containing partitioning
 208  * information for the given device @dev.
 209  */
 210 struct gendisk *get_gendisk(dev_t dev, int *part)
 211 {
 212         struct kobject *kobj = kobj_lookup(bdev_map, dev, part);
 213         return  kobj ? to_disk(kobj) : NULL;
 214 }
 215
 216 /*
 217  * print a full list of all partitions - intended for places where the root
 218  * filesystem can't be mounted and thus to give the victim some idea of what
 219  * went wrong
 220  */
 221 void __init printk_all_partitions(void)
 222 {
 223         int n;
 224         struct gendisk *sgp;
 225
 226         mutex_lock(&block_subsys_lock);
 227         /* For each block device... */
 228         list_for_each_entry(sgp, &block_subsys.list, kobj.entry) {
 229                 char buf[BDEVNAME_SIZE];
 230                 /*
 231                  * Don't show empty devices or things that have been surpressed
 232                  */
 233                 if (get_capacity(sgp) == 0 ||
 234                     (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
 235                         continue;
 236
 237                 /*
 238                  * Note, unlike /proc/partitions, I am showing the numbers in
 239                  * hex - the same format as the root= option takes.
 240                  */
 241                 printk("%02x%02x %10llu %s",
 242                         sgp->major, sgp->first_minor,
 243                         (unsigned long long)get_capacity(sgp) >> 1,
 244                         disk_name(sgp, 0, buf));
 245                 if (sgp->driverfs_dev != NULL &&
 246                     sgp->driverfs_dev->driver != NULL)
 247                         printk(" driver: %s\n",
 248                                 sgp->driverfs_dev->driver->name);
 249                 else
 250                         printk(" (driver?)\n");
 251
 252                 /* now show the partitions */
 253                 for (n = 0; n < sgp->minors - 1; ++n) {
 254                         if (sgp->part[n] == NULL)
 255                                 continue;
 256                         if (sgp->part[n]->nr_sects == 0)
 257                                 continue;
 258                         printk("  %02x%02x %10llu %s\n",
 259                                 sgp->major, n + 1 + sgp->first_minor,
 260                                 (unsigned long long)sgp->part[n]->nr_sects >> 1,
 261                                 disk_name(sgp, n + 1, buf));
 262                 } /* partition subloop */
 263         } /* Block device loop */
 264
 265         mutex_unlock(&block_subsys_lock);
 266         return;
 267 }
 268
 269 #ifdef CONFIG_PROC_FS
 270 /* iterator */
 271 static void *part_start(struct seq_file *part, loff_t *pos)
 272 {
 273         struct list_head *p;
 274         loff_t l = *pos;
 275
 276         mutex_lock(&block_subsys_lock);
 277         list_for_each(p, &block_subsys.list)
 278                 if (!l--)
 279                         return list_entry(p, struct gendisk, kobj.entry);
 280         return NULL;
 281 }
 282
 283 static void *part_next(struct seq_file *part, void *v, loff_t *pos)
 284 {
 285         struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
 286         ++*pos;
 287         return p==&block_subsys.list ? NULL :
 288                 list_entry(p, struct gendisk, kobj.entry);
 289 }
 290
 291 static void part_stop(struct seq_file *part, void *v)
 292 {
 293         mutex_unlock(&block_subsys_lock);
 294 }
 295
 296 static int show_partition(struct seq_file *part, void *v)
 297 {
 298         struct gendisk *sgp = v;
 299         int n;
 300         char buf[BDEVNAME_SIZE];
 301
 302         if (&sgp->kobj.entry == block_subsys.list.next)
 303                 seq_puts(part, "major minor  #blocks  name\n\n");
 304
 305         /* Don't show non-partitionable removeable devices or empty devices */
 306         if (!get_capacity(sgp) ||
 307                         (sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE)))
 308                 return 0;
 309         if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
 310                 return 0;
 311
 312         /* show the full disk and all non-0 size partitions of it */
 313         seq_printf(part, "%4d  %4d %10llu %s\n",
 314                 sgp->major, sgp->first_minor,
 315                 (unsigned long long)get_capacity(sgp) >> 1,
 316                 disk_name(sgp, 0, buf));
 317         for (n = 0; n < sgp->minors - 1; n++) {
 318                 if (!sgp->part[n])
 319                         continue;
 320                 if (sgp->part[n]->nr_sects == 0)
 321                         continue;
 322                 seq_printf(part, "%4d  %4d %10llu %s\n",
 323                         sgp->major, n + 1 + sgp->first_minor,
 324                         (unsigned long long)sgp->part[n]->nr_sects >> 1 ,
 325                         disk_name(sgp, n + 1, buf));
 326         }
 327
 328         return 0;
 329 }
 330
 331 struct seq_operations partitions_op = {
 332         .start =part_start,
 333         .next = part_next,
 334         .stop = part_stop,
 335         .show = show_partition
 336 };
 337 #endif
 338
 339
 340 extern int blk_dev_init(void);
 341
 342 static struct kobject *base_probe(dev_t dev, int *part, void *data)
 343 {
 344         if (request_module("block-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0)
 345                 /* Make old-style 2.4 aliases work */
 346                 request_module("block-major-%d", MAJOR(dev));
 347         return NULL;
 348 }
 349
 350 static int __init genhd_device_init(void)
 351 {
 352         int err;
 353
 354         bdev_map = kobj_map_init(base_probe, &block_subsys_lock);
 355         blk_dev_init();
 356         err = subsystem_register(&block_subsys);
 357         if (err < 0)
 358                 printk(KERN_WARNING "%s: subsystem_register error: %d\n",
 359                         __FUNCTION__, err);
 360         return err;
 361 }
 362
 363 subsys_initcall(genhd_device_init);
 364
 365
 366
 367 /*
 368  * kobject & sysfs bindings for block devices
 369  */
 370 static ssize_t disk_attr_show(struct kobject *kobj, struct attribute *attr,
 371                               char *page)
 372 {
 373         struct gendisk *disk = to_disk(kobj);
 374         struct disk_attribute *disk_attr =
 375                 container_of(attr,struct disk_attribute,attr);
 376         ssize_t ret = -EIO;
 377
 378         if (disk_attr->show)
 379                 ret = disk_attr->show(disk,page);
 380         return ret;
 381 }
 382
 383 static ssize_t disk_attr_store(struct kobject * kobj, struct attribute * attr,
 384                                const char *page, size_t count)
 385 {
 386         struct gendisk *disk = to_disk(kobj);
 387         struct disk_attribute *disk_attr =
 388                 container_of(attr,struct disk_attribute,attr);
 389         ssize_t ret = 0;
 390
 391         if (disk_attr->store)
 392                 ret = disk_attr->store(disk, page, count);
 393         return ret;
 394 }
 395
 396 static struct sysfs_ops disk_sysfs_ops = {
 397         .show   = &disk_attr_show,
 398         .store  = &disk_attr_store,
 399 };
 400
 401 static ssize_t disk_uevent_store(struct gendisk * disk,
 402                                  const char *buf, size_t count)
 403 {
 404         kobject_uevent(&disk->kobj, KOBJ_ADD);
 405         return count;
 406 }
 407 static ssize_t disk_dev_read(struct gendisk * disk, char *page)
 408 {
 409         dev_t base = MKDEV(disk->major, disk->first_minor);
 410         return print_dev_t(page, base);
 411 }
 412 static ssize_t disk_range_read(struct gendisk * disk, char *page)
 413 {
 414         return sprintf(page, "%d\n", disk->minors);
 415 }
 416 static ssize_t disk_removable_read(struct gendisk * disk, char *page)
 417 {
 418         return sprintf(page, "%d\n",
 419                        (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
 420
 421 }
 422 static ssize_t disk_size_read(struct gendisk * disk, char *page)
 423 {
 424         return sprintf(page, "%llu\n", (unsigned long long)get_capacity(disk));
 425 }
 426
 427 static ssize_t disk_stats_read(struct gendisk * disk, char *page)
 428 {
 429         preempt_disable();
 430         disk_round_stats(disk);
 431         preempt_enable();
 432         return sprintf(page,
 433                 "%8lu %8lu %8llu %8u "
 434                 "%8lu %8lu %8llu %8u "
 435                 "%8u %8u %8u"
 436                 "\n",
 437                 disk_stat_read(disk, ios[READ]),
 438                 disk_stat_read(disk, merges[READ]),
 439                 (unsigned long long)disk_stat_read(disk, sectors[READ]),
 440                 jiffies_to_msecs(disk_stat_read(disk, ticks[READ])),
 441                 disk_stat_read(disk, ios[WRITE]),
 442                 disk_stat_read(disk, merges[WRITE]),
 443                 (unsigned long long)disk_stat_read(disk, sectors[WRITE]),
 444                 jiffies_to_msecs(disk_stat_read(disk, ticks[WRITE])),
 445                 disk->in_flight,
 446                 jiffies_to_msecs(disk_stat_read(disk, io_ticks)),
 447                 jiffies_to_msecs(disk_stat_read(disk, time_in_queue)));
 448 }
 449 static struct disk_attribute disk_attr_uevent = {
 450         .attr = {.name = "uevent", .mode = S_IWUSR },
 451         .store  = disk_uevent_store
 452 };
 453 static struct disk_attribute disk_attr_dev = {
 454         .attr = {.name = "dev", .mode = S_IRUGO },
 455         .show   = disk_dev_read
 456 };
 457 static struct disk_attribute disk_attr_range = {
 458         .attr = {.name = "range", .mode = S_IRUGO },
 459         .show   = disk_range_read
 460 };
 461 static struct disk_attribute disk_attr_removable = {
 462         .attr = {.name = "removable", .mode = S_IRUGO },
 463         .show   = disk_removable_read
 464 };
 465 static struct disk_attribute disk_attr_size = {
 466         .attr = {.name = "size", .mode = S_IRUGO },
 467         .show   = disk_size_read
 468 };
 469 static struct disk_attribute disk_attr_stat = {
 470         .attr = {.name = "stat", .mode = S_IRUGO },
 471         .show   = disk_stats_read
 472 };
 473
 474 #ifdef CONFIG_FAIL_MAKE_REQUEST
 475
 476 static ssize_t disk_fail_store(struct gendisk * disk,
 477                                const char *buf, size_t count)
 478 {
 479         int i;
 480
 481         if (count > 0 && sscanf(buf, "%d", &i) > 0) {
 482                 if (i == 0)
 483                         disk->flags &= ~GENHD_FL_FAIL;
 484                 else
 485                         disk->flags |= GENHD_FL_FAIL;
 486         }
 487
 488         return count;
 489 }
 490 static ssize_t disk_fail_read(struct gendisk * disk, char *page)
 491 {
 492         return sprintf(page, "%d\n", disk->flags & GENHD_FL_FAIL ? 1 : 0);
 493 }
 494 static struct disk_attribute disk_attr_fail = {
 495         .attr = {.name = "make-it-fail", .mode = S_IRUGO | S_IWUSR },
 496         .store  = disk_fail_store,
 497         .show   = disk_fail_read
 498 };
 499
 500 #endif
 501
 502 static struct attribute * default_attrs[] = {
 503         &disk_attr_uevent.attr,
 504         &disk_attr_dev.attr,
 505         &disk_attr_range.attr,
 506         &disk_attr_removable.attr,
 507         &disk_attr_size.attr,
 508         &disk_attr_stat.attr,
 509 #ifdef CONFIG_FAIL_MAKE_REQUEST
 510         &disk_attr_fail.attr,
 511 #endif
 512         NULL,
 513 };
 514
 515 static void disk_release(struct kobject * kobj)
 516 {
 517         struct gendisk *disk = to_disk(kobj);
 518         kfree(disk->random);
 519         kfree(disk->part);
 520         free_disk_stats(disk);
 521         kfree(disk);
 522 }
 523
 524 static struct kobj_type ktype_block = {
 525         .release        = disk_release,
 526         .sysfs_ops      = &disk_sysfs_ops,
 527         .default_attrs  = default_attrs,
 528 };
 529
 530 extern struct kobj_type ktype_part;
 531
 532 static int block_uevent_filter(struct kset *kset, struct kobject *kobj)
 533 {
 534         struct kobj_type *ktype = get_ktype(kobj);
 535
 536         return ((ktype == &ktype_block) || (ktype == &ktype_part));
 537 }
 538
 539 static int block_uevent(struct kset *kset, struct kobject *kobj, char **envp,
 540                          int num_envp, char *buffer, int buffer_size)
 541 {
 542         struct kobj_type *ktype = get_ktype(kobj);
 543         struct device *physdev;
 544         struct gendisk *disk;
 545         struct hd_struct *part;
 546         int length = 0;
 547         int i = 0;
 548
 549         if (ktype == &ktype_block) {
 550                 disk = container_of(kobj, struct gendisk, kobj);
 551                 add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
 552                                &length, "MINOR=%u", disk->first_minor);
 553         } else if (ktype == &ktype_part) {
 554                 disk = container_of(kobj->parent, struct gendisk, kobj);
 555                 part = container_of(kobj, struct hd_struct, kobj);
 556                 add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
 557                                &length, "MINOR=%u",
 558                                disk->first_minor + part->partno);
 559         } else
 560                 return 0;
 561
 562         add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length,
 563                        "MAJOR=%u", disk->major);
 564
 565         /* add physical device, backing this device  */
 566         physdev = disk->driverfs_dev;
 567         if (physdev) {
 568                 char *path = kobject_get_path(&physdev->kobj, GFP_KERNEL);
 569
 570                 add_uevent_var(envp, num_envp, &i, buffer, buffer_size,
 571                                &length, "PHYSDEVPATH=%s", path);
 572                 kfree(path);
 573
 574                 if (physdev->bus)
 575                         add_uevent_var(envp, num_envp, &i,
 576                                        buffer, buffer_size, &length,
 577                                        "PHYSDEVBUS=%s",
 578                                        physdev->bus->name);
 579
 580                 if (physdev->driver)
 581                         add_uevent_var(envp, num_envp, &i,
 582                                        buffer, buffer_size, &length,
 583                                        "PHYSDEVDRIVER=%s",
 584                                        physdev->driver->name);
 585         }
 586
 587         /* terminate, set to next free slot, shrink available space */
 588         envp[i] = NULL;
 589         envp = &envp[i];
 590         num_envp -= i;
 591         buffer = &buffer[length];
 592         buffer_size -= length;
 593
 594         return 0;
 595 }
 596
 597 static struct kset_uevent_ops block_uevent_ops = {
 598         .filter         = block_uevent_filter,
 599         .uevent         = block_uevent,
 600 };
 601
 602 decl_subsys(block, &ktype_block, &block_uevent_ops);
 603
 604 /*
 605  * aggregate disk stat collector.  Uses the same stats that the sysfs
 606  * entries do, above, but makes them available through one seq_file.
 607  * Watching a few disks may be efficient through sysfs, but watching
 608  * all of them will be more efficient through this interface.
 609  *
 610  * The output looks suspiciously like /proc/partitions with a bunch of
 611  * extra fields.
 612  */
 613
 614 /* iterator */
 615 static void *diskstats_start(struct seq_file *part, loff_t *pos)
 616 {
 617         loff_t k = *pos;
 618         struct list_head *p;
 619
 620         mutex_lock(&block_subsys_lock);
 621         list_for_each(p, &block_subsys.list)
 622                 if (!k--)
 623                         return list_entry(p, struct gendisk, kobj.entry);
 624         return NULL;
 625 }
 626
 627 static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos)
 628 {
 629         struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
 630         ++*pos;
 631         return p==&block_subsys.list ? NULL :
 632                 list_entry(p, struct gendisk, kobj.entry);
 633 }
 634
 635 static void diskstats_stop(struct seq_file *part, void *v)
 636 {
 637         mutex_unlock(&block_subsys_lock);
 638 }
 639
 640 static int diskstats_show(struct seq_file *s, void *v)
 641 {
 642         struct gendisk *gp = v;
 643         char buf[BDEVNAME_SIZE];
 644         int n = 0;
 645
 646         /*
 647         if (&sgp->kobj.entry == block_subsys.kset.list.next)
 648                 seq_puts(s,     "major minor name"
 649                                 "     rio rmerge rsect ruse wio wmerge "
 650                                 "wsect wuse running use aveq"
 651                                 "\n\n");
 652         */
 653
 654         preempt_disable();
 655         disk_round_stats(gp);
 656         preempt_enable();
 657         seq_printf(s, "%4d %4d %s %lu %lu %llu %u %lu %lu %llu %u %u %u %u\n",
 658                 gp->major, n + gp->first_minor, disk_name(gp, n, buf),
 659                 disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]),
 660                 (unsigned long long)disk_stat_read(gp, sectors[0]),
 661                 jiffies_to_msecs(disk_stat_read(gp, ticks[0])),
 662                 disk_stat_read(gp, ios[1]), disk_stat_read(gp, merges[1]),
 663                 (unsigned long long)disk_stat_read(gp, sectors[1]),
 664                 jiffies_to_msecs(disk_stat_read(gp, ticks[1])),
 665                 gp->in_flight,
 666                 jiffies_to_msecs(disk_stat_read(gp, io_ticks)),
 667                 jiffies_to_msecs(disk_stat_read(gp, time_in_queue)));
 668
 669         /* now show all non-0 size partitions of it */
 670         for (n = 0; n < gp->minors - 1; n++) {
 671                 struct hd_struct *hd = gp->part[n];
 672
 673                 if (hd && hd->nr_sects)
 674                         seq_printf(s, "%4d %4d %s %u %u %u %u\n",
 675                                 gp->major, n + gp->first_minor + 1,
 676                                 disk_name(gp, n + 1, buf),
 677                                 hd->ios[0], hd->sectors[0],
 678                                 hd->ios[1], hd->sectors[1]);
 679         }
 680
 681         return 0;
 682 }
 683
 684 struct seq_operations diskstats_op = {
 685         .start  = diskstats_start,
 686         .next   = diskstats_next,
 687         .stop   = diskstats_stop,
 688         .show   = diskstats_show
 689 };
 690
 691 struct gendisk *alloc_disk(int minors)
 692 {
 693         return alloc_disk_node(minors, -1);
 694 }
 695
 696 struct gendisk *alloc_disk_node(int minors, int node_id)
 697 {
 698         struct gendisk *disk;
 699
 700         disk = kmalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
 701         if (disk) {
 702                 memset(disk, 0, sizeof(struct gendisk));
 703                 if (!init_disk_stats(disk)) {
 704                         kfree(disk);
 705                         return NULL;
 706                 }
 707                 if (minors > 1) {
 708                         int size = (minors - 1) * sizeof(struct hd_struct *);
 709                         disk->part = kmalloc_node(size, GFP_KERNEL, node_id);
 710                         if (!disk->part) {
 711                                 kfree(disk);
 712                                 return NULL;
 713                         }
 714                         memset(disk->part, 0, size);
 715                 }
 716                 disk->minors = minors;
 717                 kobj_set_kset_s(disk,block_subsys);
 718                 kobject_init(&disk->kobj);
 719                 rand_initialize_disk(disk);
 720         }
 721         return disk;
 722 }
 723
 724 EXPORT_SYMBOL(alloc_disk);
 725 EXPORT_SYMBOL(alloc_disk_node);
 726
 727 struct kobject *get_disk(struct gendisk *disk)
 728 {
 729         struct module *owner;
 730         struct kobject *kobj;
 731
 732         if (!disk->fops)
 733                 return NULL;
 734         owner = disk->fops->owner;
 735         if (owner && !try_module_get(owner))
 736                 return NULL;
 737         kobj = kobject_get(&disk->kobj);
 738         if (kobj == NULL) {
 739                 module_put(owner);
 740                 return NULL;
 741         }
 742         return kobj;
 743
 744 }
 745
 746 EXPORT_SYMBOL(get_disk);
 747
 748 void put_disk(struct gendisk *disk)
 749 {
 750         if (disk)
 751                 kobject_put(&disk->kobj);
 752 }
 753
 754 EXPORT_SYMBOL(put_disk);
 755
 756 void set_device_ro(struct block_device *bdev, int flag)
 757 {
 758         if (bdev->bd_contains != bdev)
 759                 bdev->bd_part->policy = flag;
 760         else
 761                 bdev->bd_disk->policy = flag;
 762 }
 763
 764 EXPORT_SYMBOL(set_device_ro);
 765
 766 void set_disk_ro(struct gendisk *disk, int flag)
 767 {
 768         int i;
 769         disk->policy = flag;
 770         for (i = 0; i < disk->minors - 1; i++)
 771                 if (disk->part[i]) disk->part[i]->policy = flag;
 772 }
 773
 774 EXPORT_SYMBOL(set_disk_ro);
 775
 776 int bdev_read_only(struct block_device *bdev)
 777 {
 778         if (!bdev)
 779                 return 0;
 780         else if (bdev->bd_contains != bdev)
 781                 return bdev->bd_part->policy;
 782         else
 783                 return bdev->bd_disk->policy;
 784 }
 785
 786 EXPORT_SYMBOL(bdev_read_only);
 787
 788 int invalidate_partition(struct gendisk *disk, int index)
 789 {
 790         int res = 0;
 791         struct block_device *bdev = bdget_disk(disk, index);
 792         if (bdev) {
 793                 fsync_bdev(bdev);
 794                 res = __invalidate_device(bdev);
 795                 bdput(bdev);
 796         }
 797         return res;
 798 }
 799
 800 EXPORT_SYMBOL(invalidate_partition);