Al Viro | 94ea415 | 2011-09-16 00:45:36 -0400 | [diff] [blame] | 1 | /* |
| 2 | * Code extracted from drivers/block/genhd.c |
| 3 | * Copyright (C) 1991-1998 Linus Torvalds |
| 4 | * Re-organised Feb 1998 Russell King |
| 5 | * |
| 6 | * We now have independent partition support from the |
| 7 | * block drivers, which allows all the partition code to |
| 8 | * be grouped in one location, and it to be mostly self |
| 9 | * contained. |
| 10 | */ |
| 11 | |
| 12 | #include <linux/init.h> |
| 13 | #include <linux/module.h> |
| 14 | #include <linux/fs.h> |
| 15 | #include <linux/slab.h> |
| 16 | #include <linux/kmod.h> |
| 17 | #include <linux/ctype.h> |
| 18 | #include <linux/genhd.h> |
| 19 | #include <linux/blktrace_api.h> |
| 20 | |
| 21 | #include "partitions/check.h" |
| 22 | |
| 23 | #ifdef CONFIG_BLK_DEV_MD |
| 24 | extern void md_autodetect_dev(dev_t dev); |
| 25 | #endif |
| 26 | |
| 27 | /* |
| 28 | * disk_name() is used by partition check code and the genhd driver. |
| 29 | * It formats the devicename of the indicated disk into |
| 30 | * the supplied buffer (of size at least 32), and returns |
| 31 | * a pointer to that same buffer (for convenience). |
| 32 | */ |
| 33 | |
| 34 | char *disk_name(struct gendisk *hd, int partno, char *buf) |
| 35 | { |
| 36 | if (!partno) |
| 37 | snprintf(buf, BDEVNAME_SIZE, "%s", hd->disk_name); |
| 38 | else if (isdigit(hd->disk_name[strlen(hd->disk_name)-1])) |
| 39 | snprintf(buf, BDEVNAME_SIZE, "%sp%d", hd->disk_name, partno); |
| 40 | else |
| 41 | snprintf(buf, BDEVNAME_SIZE, "%s%d", hd->disk_name, partno); |
| 42 | |
| 43 | return buf; |
| 44 | } |
| 45 | |
| 46 | const char *bdevname(struct block_device *bdev, char *buf) |
| 47 | { |
| 48 | return disk_name(bdev->bd_disk, bdev->bd_part->partno, buf); |
| 49 | } |
| 50 | |
| 51 | EXPORT_SYMBOL(bdevname); |
| 52 | |
| 53 | /* |
| 54 | * There's very little reason to use this, you should really |
| 55 | * have a struct block_device just about everywhere and use |
| 56 | * bdevname() instead. |
| 57 | */ |
| 58 | const char *__bdevname(dev_t dev, char *buffer) |
| 59 | { |
| 60 | scnprintf(buffer, BDEVNAME_SIZE, "unknown-block(%u,%u)", |
| 61 | MAJOR(dev), MINOR(dev)); |
| 62 | return buffer; |
| 63 | } |
| 64 | |
| 65 | EXPORT_SYMBOL(__bdevname); |
| 66 | |
| 67 | static ssize_t part_partition_show(struct device *dev, |
| 68 | struct device_attribute *attr, char *buf) |
| 69 | { |
| 70 | struct hd_struct *p = dev_to_part(dev); |
| 71 | |
| 72 | return sprintf(buf, "%d\n", p->partno); |
| 73 | } |
| 74 | |
| 75 | static ssize_t part_start_show(struct device *dev, |
| 76 | struct device_attribute *attr, char *buf) |
| 77 | { |
| 78 | struct hd_struct *p = dev_to_part(dev); |
| 79 | |
| 80 | return sprintf(buf, "%llu\n",(unsigned long long)p->start_sect); |
| 81 | } |
| 82 | |
| 83 | ssize_t part_size_show(struct device *dev, |
| 84 | struct device_attribute *attr, char *buf) |
| 85 | { |
| 86 | struct hd_struct *p = dev_to_part(dev); |
| 87 | return sprintf(buf, "%llu\n",(unsigned long long)p->nr_sects); |
| 88 | } |
| 89 | |
| 90 | static ssize_t part_ro_show(struct device *dev, |
| 91 | struct device_attribute *attr, char *buf) |
| 92 | { |
| 93 | struct hd_struct *p = dev_to_part(dev); |
| 94 | return sprintf(buf, "%d\n", p->policy ? 1 : 0); |
| 95 | } |
| 96 | |
| 97 | static ssize_t part_alignment_offset_show(struct device *dev, |
| 98 | struct device_attribute *attr, char *buf) |
| 99 | { |
| 100 | struct hd_struct *p = dev_to_part(dev); |
| 101 | return sprintf(buf, "%llu\n", (unsigned long long)p->alignment_offset); |
| 102 | } |
| 103 | |
| 104 | static ssize_t part_discard_alignment_show(struct device *dev, |
| 105 | struct device_attribute *attr, char *buf) |
| 106 | { |
| 107 | struct hd_struct *p = dev_to_part(dev); |
| 108 | return sprintf(buf, "%u\n", p->discard_alignment); |
| 109 | } |
| 110 | |
| 111 | ssize_t part_stat_show(struct device *dev, |
| 112 | struct device_attribute *attr, char *buf) |
| 113 | { |
| 114 | struct hd_struct *p = dev_to_part(dev); |
| 115 | int cpu; |
| 116 | |
| 117 | cpu = part_stat_lock(); |
| 118 | part_round_stats(cpu, p); |
| 119 | part_stat_unlock(); |
| 120 | return sprintf(buf, |
| 121 | "%8lu %8lu %8llu %8u " |
| 122 | "%8lu %8lu %8llu %8u " |
| 123 | "%8u %8u %8u" |
| 124 | "\n", |
| 125 | part_stat_read(p, ios[READ]), |
| 126 | part_stat_read(p, merges[READ]), |
| 127 | (unsigned long long)part_stat_read(p, sectors[READ]), |
| 128 | jiffies_to_msecs(part_stat_read(p, ticks[READ])), |
| 129 | part_stat_read(p, ios[WRITE]), |
| 130 | part_stat_read(p, merges[WRITE]), |
| 131 | (unsigned long long)part_stat_read(p, sectors[WRITE]), |
| 132 | jiffies_to_msecs(part_stat_read(p, ticks[WRITE])), |
| 133 | part_in_flight(p), |
| 134 | jiffies_to_msecs(part_stat_read(p, io_ticks)), |
| 135 | jiffies_to_msecs(part_stat_read(p, time_in_queue))); |
| 136 | } |
| 137 | |
| 138 | ssize_t part_inflight_show(struct device *dev, |
| 139 | struct device_attribute *attr, char *buf) |
| 140 | { |
| 141 | struct hd_struct *p = dev_to_part(dev); |
| 142 | |
| 143 | return sprintf(buf, "%8u %8u\n", atomic_read(&p->in_flight[0]), |
| 144 | atomic_read(&p->in_flight[1])); |
| 145 | } |
| 146 | |
| 147 | #ifdef CONFIG_FAIL_MAKE_REQUEST |
| 148 | ssize_t part_fail_show(struct device *dev, |
| 149 | struct device_attribute *attr, char *buf) |
| 150 | { |
| 151 | struct hd_struct *p = dev_to_part(dev); |
| 152 | |
| 153 | return sprintf(buf, "%d\n", p->make_it_fail); |
| 154 | } |
| 155 | |
| 156 | ssize_t part_fail_store(struct device *dev, |
| 157 | struct device_attribute *attr, |
| 158 | const char *buf, size_t count) |
| 159 | { |
| 160 | struct hd_struct *p = dev_to_part(dev); |
| 161 | int i; |
| 162 | |
| 163 | if (count > 0 && sscanf(buf, "%d", &i) > 0) |
| 164 | p->make_it_fail = (i == 0) ? 0 : 1; |
| 165 | |
| 166 | return count; |
| 167 | } |
| 168 | #endif |
| 169 | |
| 170 | static DEVICE_ATTR(partition, S_IRUGO, part_partition_show, NULL); |
| 171 | static DEVICE_ATTR(start, S_IRUGO, part_start_show, NULL); |
| 172 | static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL); |
| 173 | static DEVICE_ATTR(ro, S_IRUGO, part_ro_show, NULL); |
| 174 | static DEVICE_ATTR(alignment_offset, S_IRUGO, part_alignment_offset_show, NULL); |
| 175 | static DEVICE_ATTR(discard_alignment, S_IRUGO, part_discard_alignment_show, |
| 176 | NULL); |
| 177 | static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL); |
| 178 | static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL); |
| 179 | #ifdef CONFIG_FAIL_MAKE_REQUEST |
| 180 | static struct device_attribute dev_attr_fail = |
| 181 | __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store); |
| 182 | #endif |
| 183 | |
| 184 | static struct attribute *part_attrs[] = { |
| 185 | &dev_attr_partition.attr, |
| 186 | &dev_attr_start.attr, |
| 187 | &dev_attr_size.attr, |
| 188 | &dev_attr_ro.attr, |
| 189 | &dev_attr_alignment_offset.attr, |
| 190 | &dev_attr_discard_alignment.attr, |
| 191 | &dev_attr_stat.attr, |
| 192 | &dev_attr_inflight.attr, |
| 193 | #ifdef CONFIG_FAIL_MAKE_REQUEST |
| 194 | &dev_attr_fail.attr, |
| 195 | #endif |
| 196 | NULL |
| 197 | }; |
| 198 | |
| 199 | static struct attribute_group part_attr_group = { |
| 200 | .attrs = part_attrs, |
| 201 | }; |
| 202 | |
| 203 | static const struct attribute_group *part_attr_groups[] = { |
| 204 | &part_attr_group, |
| 205 | #ifdef CONFIG_BLK_DEV_IO_TRACE |
| 206 | &blk_trace_attr_group, |
| 207 | #endif |
| 208 | NULL |
| 209 | }; |
| 210 | |
| 211 | static void part_release(struct device *dev) |
| 212 | { |
| 213 | struct hd_struct *p = dev_to_part(dev); |
| 214 | free_part_stats(p); |
| 215 | free_part_info(p); |
| 216 | kfree(p); |
| 217 | } |
| 218 | |
San Mehat | 38c6302 | 2009-10-10 09:35:24 -0700 | [diff] [blame^] | 219 | static int part_uevent(struct device *dev, struct kobj_uevent_env *env) |
| 220 | { |
| 221 | struct hd_struct *part = dev_to_part(dev); |
| 222 | |
| 223 | add_uevent_var(env, "PARTN=%u", part->partno); |
| 224 | if (part->info && part->info->volname[0]) |
| 225 | add_uevent_var(env, "PARTNAME=%s", part->info->volname); |
| 226 | return 0; |
| 227 | } |
| 228 | |
Al Viro | 94ea415 | 2011-09-16 00:45:36 -0400 | [diff] [blame] | 229 | struct device_type part_type = { |
| 230 | .name = "partition", |
| 231 | .groups = part_attr_groups, |
| 232 | .release = part_release, |
San Mehat | 38c6302 | 2009-10-10 09:35:24 -0700 | [diff] [blame^] | 233 | .uevent = part_uevent, |
Al Viro | 94ea415 | 2011-09-16 00:45:36 -0400 | [diff] [blame] | 234 | }; |
| 235 | |
| 236 | static void delete_partition_rcu_cb(struct rcu_head *head) |
| 237 | { |
| 238 | struct hd_struct *part = container_of(head, struct hd_struct, rcu_head); |
| 239 | |
| 240 | part->start_sect = 0; |
| 241 | part->nr_sects = 0; |
| 242 | part_stat_set_all(part, 0); |
| 243 | put_device(part_to_dev(part)); |
| 244 | } |
| 245 | |
| 246 | void __delete_partition(struct hd_struct *part) |
| 247 | { |
| 248 | call_rcu(&part->rcu_head, delete_partition_rcu_cb); |
| 249 | } |
| 250 | |
| 251 | void delete_partition(struct gendisk *disk, int partno) |
| 252 | { |
| 253 | struct disk_part_tbl *ptbl = disk->part_tbl; |
| 254 | struct hd_struct *part; |
| 255 | |
| 256 | if (partno >= ptbl->len) |
| 257 | return; |
| 258 | |
| 259 | part = ptbl->part[partno]; |
| 260 | if (!part) |
| 261 | return; |
| 262 | |
| 263 | blk_free_devt(part_devt(part)); |
| 264 | rcu_assign_pointer(ptbl->part[partno], NULL); |
| 265 | rcu_assign_pointer(ptbl->last_lookup, NULL); |
| 266 | kobject_put(part->holder_dir); |
| 267 | device_del(part_to_dev(part)); |
| 268 | |
| 269 | hd_struct_put(part); |
| 270 | } |
| 271 | |
| 272 | static ssize_t whole_disk_show(struct device *dev, |
| 273 | struct device_attribute *attr, char *buf) |
| 274 | { |
| 275 | return 0; |
| 276 | } |
| 277 | static DEVICE_ATTR(whole_disk, S_IRUSR | S_IRGRP | S_IROTH, |
| 278 | whole_disk_show, NULL); |
| 279 | |
| 280 | struct hd_struct *add_partition(struct gendisk *disk, int partno, |
| 281 | sector_t start, sector_t len, int flags, |
| 282 | struct partition_meta_info *info) |
| 283 | { |
| 284 | struct hd_struct *p; |
| 285 | dev_t devt = MKDEV(0, 0); |
| 286 | struct device *ddev = disk_to_dev(disk); |
| 287 | struct device *pdev; |
| 288 | struct disk_part_tbl *ptbl; |
| 289 | const char *dname; |
| 290 | int err; |
| 291 | |
| 292 | err = disk_expand_part_tbl(disk, partno); |
| 293 | if (err) |
| 294 | return ERR_PTR(err); |
| 295 | ptbl = disk->part_tbl; |
| 296 | |
| 297 | if (ptbl->part[partno]) |
| 298 | return ERR_PTR(-EBUSY); |
| 299 | |
| 300 | p = kzalloc(sizeof(*p), GFP_KERNEL); |
| 301 | if (!p) |
| 302 | return ERR_PTR(-EBUSY); |
| 303 | |
| 304 | if (!init_part_stats(p)) { |
| 305 | err = -ENOMEM; |
| 306 | goto out_free; |
| 307 | } |
| 308 | pdev = part_to_dev(p); |
| 309 | |
| 310 | p->start_sect = start; |
| 311 | p->alignment_offset = |
| 312 | queue_limit_alignment_offset(&disk->queue->limits, start); |
| 313 | p->discard_alignment = |
| 314 | queue_limit_discard_alignment(&disk->queue->limits, start); |
| 315 | p->nr_sects = len; |
| 316 | p->partno = partno; |
| 317 | p->policy = get_disk_ro(disk); |
| 318 | |
| 319 | if (info) { |
| 320 | struct partition_meta_info *pinfo = alloc_part_info(disk); |
| 321 | if (!pinfo) |
| 322 | goto out_free_stats; |
| 323 | memcpy(pinfo, info, sizeof(*info)); |
| 324 | p->info = pinfo; |
| 325 | } |
| 326 | |
| 327 | dname = dev_name(ddev); |
| 328 | if (isdigit(dname[strlen(dname) - 1])) |
| 329 | dev_set_name(pdev, "%sp%d", dname, partno); |
| 330 | else |
| 331 | dev_set_name(pdev, "%s%d", dname, partno); |
| 332 | |
| 333 | device_initialize(pdev); |
| 334 | pdev->class = &block_class; |
| 335 | pdev->type = &part_type; |
| 336 | pdev->parent = ddev; |
| 337 | |
| 338 | err = blk_alloc_devt(p, &devt); |
| 339 | if (err) |
| 340 | goto out_free_info; |
| 341 | pdev->devt = devt; |
| 342 | |
| 343 | /* delay uevent until 'holders' subdir is created */ |
| 344 | dev_set_uevent_suppress(pdev, 1); |
| 345 | err = device_add(pdev); |
| 346 | if (err) |
| 347 | goto out_put; |
| 348 | |
| 349 | err = -ENOMEM; |
| 350 | p->holder_dir = kobject_create_and_add("holders", &pdev->kobj); |
| 351 | if (!p->holder_dir) |
| 352 | goto out_del; |
| 353 | |
| 354 | dev_set_uevent_suppress(pdev, 0); |
| 355 | if (flags & ADDPART_FLAG_WHOLEDISK) { |
| 356 | err = device_create_file(pdev, &dev_attr_whole_disk); |
| 357 | if (err) |
| 358 | goto out_del; |
| 359 | } |
| 360 | |
| 361 | /* everything is up and running, commence */ |
| 362 | rcu_assign_pointer(ptbl->part[partno], p); |
| 363 | |
| 364 | /* suppress uevent if the disk suppresses it */ |
| 365 | if (!dev_get_uevent_suppress(ddev)) |
| 366 | kobject_uevent(&pdev->kobj, KOBJ_ADD); |
| 367 | |
| 368 | hd_ref_init(p); |
| 369 | return p; |
| 370 | |
| 371 | out_free_info: |
| 372 | free_part_info(p); |
| 373 | out_free_stats: |
| 374 | free_part_stats(p); |
| 375 | out_free: |
| 376 | kfree(p); |
| 377 | return ERR_PTR(err); |
| 378 | out_del: |
| 379 | kobject_put(p->holder_dir); |
| 380 | device_del(pdev); |
| 381 | out_put: |
| 382 | put_device(pdev); |
| 383 | blk_free_devt(devt); |
| 384 | return ERR_PTR(err); |
| 385 | } |
| 386 | |
| 387 | static bool disk_unlock_native_capacity(struct gendisk *disk) |
| 388 | { |
| 389 | const struct block_device_operations *bdops = disk->fops; |
| 390 | |
| 391 | if (bdops->unlock_native_capacity && |
| 392 | !(disk->flags & GENHD_FL_NATIVE_CAPACITY)) { |
| 393 | printk(KERN_CONT "enabling native capacity\n"); |
| 394 | bdops->unlock_native_capacity(disk); |
| 395 | disk->flags |= GENHD_FL_NATIVE_CAPACITY; |
| 396 | return true; |
| 397 | } else { |
| 398 | printk(KERN_CONT "truncated\n"); |
| 399 | return false; |
| 400 | } |
| 401 | } |
| 402 | |
Jun'ichi Nomura | fe316bf | 2012-03-02 10:38:33 +0100 | [diff] [blame] | 403 | static int drop_partitions(struct gendisk *disk, struct block_device *bdev) |
Al Viro | 94ea415 | 2011-09-16 00:45:36 -0400 | [diff] [blame] | 404 | { |
Al Viro | 94ea415 | 2011-09-16 00:45:36 -0400 | [diff] [blame] | 405 | struct disk_part_iter piter; |
| 406 | struct hd_struct *part; |
Jun'ichi Nomura | fe316bf | 2012-03-02 10:38:33 +0100 | [diff] [blame] | 407 | int res; |
Al Viro | 94ea415 | 2011-09-16 00:45:36 -0400 | [diff] [blame] | 408 | |
| 409 | if (bdev->bd_part_count) |
| 410 | return -EBUSY; |
| 411 | res = invalidate_partition(disk, 0); |
| 412 | if (res) |
| 413 | return res; |
| 414 | |
| 415 | disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY); |
| 416 | while ((part = disk_part_iter_next(&piter))) |
| 417 | delete_partition(disk, part->partno); |
| 418 | disk_part_iter_exit(&piter); |
| 419 | |
Jun'ichi Nomura | fe316bf | 2012-03-02 10:38:33 +0100 | [diff] [blame] | 420 | return 0; |
| 421 | } |
| 422 | |
| 423 | int rescan_partitions(struct gendisk *disk, struct block_device *bdev) |
| 424 | { |
| 425 | struct parsed_partitions *state = NULL; |
| 426 | struct hd_struct *part; |
| 427 | int p, highest, res; |
| 428 | rescan: |
| 429 | if (state && !IS_ERR(state)) { |
| 430 | kfree(state); |
| 431 | state = NULL; |
| 432 | } |
| 433 | |
| 434 | res = drop_partitions(disk, bdev); |
| 435 | if (res) |
| 436 | return res; |
| 437 | |
Al Viro | 94ea415 | 2011-09-16 00:45:36 -0400 | [diff] [blame] | 438 | if (disk->fops->revalidate_disk) |
| 439 | disk->fops->revalidate_disk(disk); |
| 440 | check_disk_size_change(disk, bdev); |
| 441 | bdev->bd_invalidated = 0; |
| 442 | if (!get_capacity(disk) || !(state = check_partition(disk, bdev))) |
| 443 | return 0; |
| 444 | if (IS_ERR(state)) { |
| 445 | /* |
| 446 | * I/O error reading the partition table. If any |
| 447 | * partition code tried to read beyond EOD, retry |
| 448 | * after unlocking native capacity. |
| 449 | */ |
| 450 | if (PTR_ERR(state) == -ENOSPC) { |
| 451 | printk(KERN_WARNING "%s: partition table beyond EOD, ", |
| 452 | disk->disk_name); |
| 453 | if (disk_unlock_native_capacity(disk)) |
| 454 | goto rescan; |
| 455 | } |
| 456 | return -EIO; |
| 457 | } |
| 458 | /* |
| 459 | * If any partition code tried to read beyond EOD, try |
| 460 | * unlocking native capacity even if partition table is |
| 461 | * successfully read as we could be missing some partitions. |
| 462 | */ |
| 463 | if (state->access_beyond_eod) { |
| 464 | printk(KERN_WARNING |
| 465 | "%s: partition table partially beyond EOD, ", |
| 466 | disk->disk_name); |
| 467 | if (disk_unlock_native_capacity(disk)) |
| 468 | goto rescan; |
| 469 | } |
| 470 | |
| 471 | /* tell userspace that the media / partition table may have changed */ |
| 472 | kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); |
| 473 | |
| 474 | /* Detect the highest partition number and preallocate |
| 475 | * disk->part_tbl. This is an optimization and not strictly |
| 476 | * necessary. |
| 477 | */ |
| 478 | for (p = 1, highest = 0; p < state->limit; p++) |
| 479 | if (state->parts[p].size) |
| 480 | highest = p; |
| 481 | |
| 482 | disk_expand_part_tbl(disk, highest); |
| 483 | |
| 484 | /* add partitions */ |
| 485 | for (p = 1; p < state->limit; p++) { |
| 486 | sector_t size, from; |
| 487 | struct partition_meta_info *info = NULL; |
| 488 | |
| 489 | size = state->parts[p].size; |
| 490 | if (!size) |
| 491 | continue; |
| 492 | |
| 493 | from = state->parts[p].from; |
| 494 | if (from >= get_capacity(disk)) { |
| 495 | printk(KERN_WARNING |
| 496 | "%s: p%d start %llu is beyond EOD, ", |
| 497 | disk->disk_name, p, (unsigned long long) from); |
| 498 | if (disk_unlock_native_capacity(disk)) |
| 499 | goto rescan; |
| 500 | continue; |
| 501 | } |
| 502 | |
| 503 | if (from + size > get_capacity(disk)) { |
| 504 | printk(KERN_WARNING |
| 505 | "%s: p%d size %llu extends beyond EOD, ", |
| 506 | disk->disk_name, p, (unsigned long long) size); |
| 507 | |
| 508 | if (disk_unlock_native_capacity(disk)) { |
| 509 | /* free state and restart */ |
| 510 | goto rescan; |
| 511 | } else { |
| 512 | /* |
| 513 | * we can not ignore partitions of broken tables |
| 514 | * created by for example camera firmware, but |
| 515 | * we limit them to the end of the disk to avoid |
| 516 | * creating invalid block devices |
| 517 | */ |
| 518 | size = get_capacity(disk) - from; |
| 519 | } |
| 520 | } |
| 521 | |
| 522 | if (state->parts[p].has_info) |
| 523 | info = &state->parts[p].info; |
| 524 | part = add_partition(disk, p, from, size, |
| 525 | state->parts[p].flags, |
| 526 | &state->parts[p].info); |
| 527 | if (IS_ERR(part)) { |
| 528 | printk(KERN_ERR " %s: p%d could not be added: %ld\n", |
| 529 | disk->disk_name, p, -PTR_ERR(part)); |
| 530 | continue; |
| 531 | } |
| 532 | #ifdef CONFIG_BLK_DEV_MD |
| 533 | if (state->parts[p].flags & ADDPART_FLAG_RAID) |
| 534 | md_autodetect_dev(part_to_dev(part)->devt); |
| 535 | #endif |
| 536 | } |
| 537 | kfree(state); |
| 538 | return 0; |
| 539 | } |
| 540 | |
Jun'ichi Nomura | fe316bf | 2012-03-02 10:38:33 +0100 | [diff] [blame] | 541 | int invalidate_partitions(struct gendisk *disk, struct block_device *bdev) |
| 542 | { |
| 543 | int res; |
| 544 | |
| 545 | if (!bdev->bd_invalidated) |
| 546 | return 0; |
| 547 | |
| 548 | res = drop_partitions(disk, bdev); |
| 549 | if (res) |
| 550 | return res; |
| 551 | |
| 552 | set_capacity(disk, 0); |
| 553 | check_disk_size_change(disk, bdev); |
| 554 | bdev->bd_invalidated = 0; |
| 555 | /* tell userspace that the media / partition table may have changed */ |
| 556 | kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); |
| 557 | |
| 558 | return 0; |
| 559 | } |
| 560 | |
Al Viro | 94ea415 | 2011-09-16 00:45:36 -0400 | [diff] [blame] | 561 | unsigned char *read_dev_sector(struct block_device *bdev, sector_t n, Sector *p) |
| 562 | { |
| 563 | struct address_space *mapping = bdev->bd_inode->i_mapping; |
| 564 | struct page *page; |
| 565 | |
| 566 | page = read_mapping_page(mapping, (pgoff_t)(n >> (PAGE_CACHE_SHIFT-9)), |
| 567 | NULL); |
| 568 | if (!IS_ERR(page)) { |
| 569 | if (PageError(page)) |
| 570 | goto fail; |
| 571 | p->v = page; |
| 572 | return (unsigned char *)page_address(page) + ((n & ((1 << (PAGE_CACHE_SHIFT - 9)) - 1)) << 9); |
| 573 | fail: |
| 574 | page_cache_release(page); |
| 575 | } |
| 576 | p->v = NULL; |
| 577 | return NULL; |
| 578 | } |
| 579 | |
| 580 | EXPORT_SYMBOL(read_dev_sector); |