1 #include <linux/capability.h> 2 #include <linux/blkdev.h> 3 #include <linux/export.h> 4 #include <linux/gfp.h> 5 #include <linux/blkpg.h> 6 #include <linux/hdreg.h> 7 #include <linux/backing-dev.h> 8 #include <linux/fs.h> 9 #include <linux/blktrace_api.h> 10 #include <linux/pr.h> 11 #include <linux/uaccess.h> 12 13 static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg) 14 { 15 struct block_device *bdevp; 16 struct gendisk *disk; 17 struct hd_struct *part, *lpart; 18 struct blkpg_ioctl_arg a; 19 struct blkpg_partition p; 20 struct disk_part_iter piter; 21 long long start, length; 22 int partno; 23 24 if (!capable(CAP_SYS_ADMIN)) 25 return -EACCES; 26 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg))) 27 return -EFAULT; 28 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition))) 29 return -EFAULT; 30 disk = bdev->bd_disk; 31 if (bdev != bdev->bd_contains) 32 return -EINVAL; 33 partno = p.pno; 34 if (partno <= 0) 35 return -EINVAL; 36 switch (a.op) { 37 case BLKPG_ADD_PARTITION: 38 start = p.start >> 9; 39 length = p.length >> 9; 40 /* check for fit in a hd_struct */ 41 if (sizeof(sector_t) == sizeof(long) && 42 sizeof(long long) > sizeof(long)) { 43 long pstart = start, plength = length; 44 if (pstart != start || plength != length 45 || pstart < 0 || plength < 0 || partno > 65535) 46 return -EINVAL; 47 } 48 /* check if partition is aligned to blocksize */ 49 if (p.start & (bdev_logical_block_size(bdev) - 1)) 50 return -EINVAL; 51 52 mutex_lock(&bdev->bd_mutex); 53 54 /* overlap? */ 55 disk_part_iter_init(&piter, disk, 56 DISK_PITER_INCL_EMPTY); 57 while ((part = disk_part_iter_next(&piter))) { 58 if (!(start + length <= part->start_sect || 59 start >= part->start_sect + part->nr_sects)) { 60 disk_part_iter_exit(&piter); 61 mutex_unlock(&bdev->bd_mutex); 62 return -EBUSY; 63 } 64 } 65 disk_part_iter_exit(&piter); 66 67 /* all seems OK */ 68 part = add_partition(disk, partno, start, length, 69 ADDPART_FLAG_NONE, NULL); 70 mutex_unlock(&bdev->bd_mutex); 71 return PTR_ERR_OR_ZERO(part); 72 case BLKPG_DEL_PARTITION: 73 part = disk_get_part(disk, partno); 74 if (!part) 75 return -ENXIO; 76 77 bdevp = bdget(part_devt(part)); 78 disk_put_part(part); 79 if (!bdevp) 80 return -ENOMEM; 81 82 mutex_lock(&bdevp->bd_mutex); 83 if (bdevp->bd_openers) { 84 mutex_unlock(&bdevp->bd_mutex); 85 bdput(bdevp); 86 return -EBUSY; 87 } 88 /* all seems OK */ 89 fsync_bdev(bdevp); 90 invalidate_bdev(bdevp); 91 92 mutex_lock_nested(&bdev->bd_mutex, 1); 93 delete_partition(disk, partno); 94 mutex_unlock(&bdev->bd_mutex); 95 mutex_unlock(&bdevp->bd_mutex); 96 bdput(bdevp); 97 98 return 0; 99 case BLKPG_RESIZE_PARTITION: 100 start = p.start >> 9; 101 /* new length of partition in bytes */ 102 length = p.length >> 9; 103 /* check for fit in a hd_struct */ 104 if (sizeof(sector_t) == sizeof(long) && 105 sizeof(long long) > sizeof(long)) { 106 long pstart = start, plength = length; 107 if (pstart != start || plength != length 108 || pstart < 0 || plength < 0) 109 return -EINVAL; 110 } 111 part = disk_get_part(disk, partno); 112 if (!part) 113 return -ENXIO; 114 bdevp = bdget(part_devt(part)); 115 if (!bdevp) { 116 disk_put_part(part); 117 return -ENOMEM; 118 } 119 mutex_lock(&bdevp->bd_mutex); 120 mutex_lock_nested(&bdev->bd_mutex, 1); 121 if (start != part->start_sect) { 122 mutex_unlock(&bdevp->bd_mutex); 123 mutex_unlock(&bdev->bd_mutex); 124 bdput(bdevp); 125 disk_put_part(part); 126 return -EINVAL; 127 } 128 /* overlap? */ 129 disk_part_iter_init(&piter, disk, 130 DISK_PITER_INCL_EMPTY); 131 while ((lpart = disk_part_iter_next(&piter))) { 132 if (lpart->partno != partno && 133 !(start + length <= lpart->start_sect || 134 start >= lpart->start_sect + lpart->nr_sects) 135 ) { 136 disk_part_iter_exit(&piter); 137 mutex_unlock(&bdevp->bd_mutex); 138 mutex_unlock(&bdev->bd_mutex); 139 bdput(bdevp); 140 disk_put_part(part); 141 return -EBUSY; 142 } 143 } 144 disk_part_iter_exit(&piter); 145 part_nr_sects_write(part, (sector_t)length); 146 i_size_write(bdevp->bd_inode, p.length); 147 mutex_unlock(&bdevp->bd_mutex); 148 mutex_unlock(&bdev->bd_mutex); 149 bdput(bdevp); 150 disk_put_part(part); 151 return 0; 152 default: 153 return -EINVAL; 154 } 155 } 156 157 /* 158 * This is an exported API for the block driver, and will not 159 * acquire bd_mutex. This API should be used in case that 160 * caller has held bd_mutex already. 161 */ 162 int __blkdev_reread_part(struct block_device *bdev) 163 { 164 struct gendisk *disk = bdev->bd_disk; 165 166 if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains) 167 return -EINVAL; 168 if (!capable(CAP_SYS_ADMIN)) 169 return -EACCES; 170 171 lockdep_assert_held(&bdev->bd_mutex); 172 173 return rescan_partitions(disk, bdev); 174 } 175 EXPORT_SYMBOL(__blkdev_reread_part); 176 177 /* 178 * This is an exported API for the block driver, and will 179 * try to acquire bd_mutex. If bd_mutex has been held already 180 * in current context, please call __blkdev_reread_part(). 181 * 182 * Make sure the held locks in current context aren't required 183 * in open()/close() handler and I/O path for avoiding ABBA deadlock: 184 * - bd_mutex is held before calling block driver's open/close 185 * handler 186 * - reading partition table may submit I/O to the block device 187 */ 188 int blkdev_reread_part(struct block_device *bdev) 189 { 190 int res; 191 192 mutex_lock(&bdev->bd_mutex); 193 res = __blkdev_reread_part(bdev); 194 mutex_unlock(&bdev->bd_mutex); 195 196 return res; 197 } 198 EXPORT_SYMBOL(blkdev_reread_part); 199 200 static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode, 201 unsigned long arg, unsigned long flags) 202 { 203 uint64_t range[2]; 204 uint64_t start, len; 205 struct request_queue *q = bdev_get_queue(bdev); 206 struct address_space *mapping = bdev->bd_inode->i_mapping; 207 208 209 if (!(mode & FMODE_WRITE)) 210 return -EBADF; 211 212 if (!blk_queue_discard(q)) 213 return -EOPNOTSUPP; 214 215 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 216 return -EFAULT; 217 218 start = range[0]; 219 len = range[1]; 220 221 if (start & 511) 222 return -EINVAL; 223 if (len & 511) 224 return -EINVAL; 225 226 if (start + len > i_size_read(bdev->bd_inode)) 227 return -EINVAL; 228 truncate_inode_pages_range(mapping, start, start + len - 1); 229 return blkdev_issue_discard(bdev, start >> 9, len >> 9, 230 GFP_KERNEL, flags); 231 } 232 233 static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode, 234 unsigned long arg) 235 { 236 uint64_t range[2]; 237 struct address_space *mapping; 238 uint64_t start, end, len; 239 240 if (!(mode & FMODE_WRITE)) 241 return -EBADF; 242 243 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 244 return -EFAULT; 245 246 start = range[0]; 247 len = range[1]; 248 end = start + len - 1; 249 250 if (start & 511) 251 return -EINVAL; 252 if (len & 511) 253 return -EINVAL; 254 if (end >= (uint64_t)i_size_read(bdev->bd_inode)) 255 return -EINVAL; 256 if (end < start) 257 return -EINVAL; 258 259 /* Invalidate the page cache, including dirty pages */ 260 mapping = bdev->bd_inode->i_mapping; 261 truncate_inode_pages_range(mapping, start, end); 262 263 return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL, 264 BLKDEV_ZERO_NOUNMAP); 265 } 266 267 static int put_ushort(unsigned long arg, unsigned short val) 268 { 269 return put_user(val, (unsigned short __user *)arg); 270 } 271 272 static int put_int(unsigned long arg, int val) 273 { 274 return put_user(val, (int __user *)arg); 275 } 276 277 static int put_uint(unsigned long arg, unsigned int val) 278 { 279 return put_user(val, (unsigned int __user *)arg); 280 } 281 282 static int put_long(unsigned long arg, long val) 283 { 284 return put_user(val, (long __user *)arg); 285 } 286 287 static int put_ulong(unsigned long arg, unsigned long val) 288 { 289 return put_user(val, (unsigned long __user *)arg); 290 } 291 292 static int put_u64(unsigned long arg, u64 val) 293 { 294 return put_user(val, (u64 __user *)arg); 295 } 296 297 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode, 298 unsigned cmd, unsigned long arg) 299 { 300 struct gendisk *disk = bdev->bd_disk; 301 302 if (disk->fops->ioctl) 303 return disk->fops->ioctl(bdev, mode, cmd, arg); 304 305 return -ENOTTY; 306 } 307 /* 308 * For the record: _GPL here is only because somebody decided to slap it 309 * on the previous export. Sheer idiocy, since it wasn't copyrightable 310 * at all and could be open-coded without any exports by anybody who cares. 311 */ 312 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl); 313 314 static int blkdev_pr_register(struct block_device *bdev, 315 struct pr_registration __user *arg) 316 { 317 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 318 struct pr_registration reg; 319 320 if (!capable(CAP_SYS_ADMIN)) 321 return -EPERM; 322 if (!ops || !ops->pr_register) 323 return -EOPNOTSUPP; 324 if (copy_from_user(®, arg, sizeof(reg))) 325 return -EFAULT; 326 327 if (reg.flags & ~PR_FL_IGNORE_KEY) 328 return -EOPNOTSUPP; 329 return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags); 330 } 331 332 static int blkdev_pr_reserve(struct block_device *bdev, 333 struct pr_reservation __user *arg) 334 { 335 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 336 struct pr_reservation rsv; 337 338 if (!capable(CAP_SYS_ADMIN)) 339 return -EPERM; 340 if (!ops || !ops->pr_reserve) 341 return -EOPNOTSUPP; 342 if (copy_from_user(&rsv, arg, sizeof(rsv))) 343 return -EFAULT; 344 345 if (rsv.flags & ~PR_FL_IGNORE_KEY) 346 return -EOPNOTSUPP; 347 return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags); 348 } 349 350 static int blkdev_pr_release(struct block_device *bdev, 351 struct pr_reservation __user *arg) 352 { 353 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 354 struct pr_reservation rsv; 355 356 if (!capable(CAP_SYS_ADMIN)) 357 return -EPERM; 358 if (!ops || !ops->pr_release) 359 return -EOPNOTSUPP; 360 if (copy_from_user(&rsv, arg, sizeof(rsv))) 361 return -EFAULT; 362 363 if (rsv.flags) 364 return -EOPNOTSUPP; 365 return ops->pr_release(bdev, rsv.key, rsv.type); 366 } 367 368 static int blkdev_pr_preempt(struct block_device *bdev, 369 struct pr_preempt __user *arg, bool abort) 370 { 371 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 372 struct pr_preempt p; 373 374 if (!capable(CAP_SYS_ADMIN)) 375 return -EPERM; 376 if (!ops || !ops->pr_preempt) 377 return -EOPNOTSUPP; 378 if (copy_from_user(&p, arg, sizeof(p))) 379 return -EFAULT; 380 381 if (p.flags) 382 return -EOPNOTSUPP; 383 return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort); 384 } 385 386 static int blkdev_pr_clear(struct block_device *bdev, 387 struct pr_clear __user *arg) 388 { 389 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 390 struct pr_clear c; 391 392 if (!capable(CAP_SYS_ADMIN)) 393 return -EPERM; 394 if (!ops || !ops->pr_clear) 395 return -EOPNOTSUPP; 396 if (copy_from_user(&c, arg, sizeof(c))) 397 return -EFAULT; 398 399 if (c.flags) 400 return -EOPNOTSUPP; 401 return ops->pr_clear(bdev, c.key); 402 } 403 404 /* 405 * Is it an unrecognized ioctl? The correct returns are either 406 * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a 407 * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl 408 * code before returning. 409 * 410 * Confused drivers sometimes return EINVAL, which is wrong. It 411 * means "I understood the ioctl command, but the parameters to 412 * it were wrong". 413 * 414 * We should aim to just fix the broken drivers, the EINVAL case 415 * should go away. 416 */ 417 static inline int is_unrecognized_ioctl(int ret) 418 { 419 return ret == -EINVAL || 420 ret == -ENOTTY || 421 ret == -ENOIOCTLCMD; 422 } 423 424 static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode, 425 unsigned cmd, unsigned long arg) 426 { 427 int ret; 428 429 if (!capable(CAP_SYS_ADMIN)) 430 return -EACCES; 431 432 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 433 if (!is_unrecognized_ioctl(ret)) 434 return ret; 435 436 fsync_bdev(bdev); 437 invalidate_bdev(bdev); 438 return 0; 439 } 440 441 static int blkdev_roset(struct block_device *bdev, fmode_t mode, 442 unsigned cmd, unsigned long arg) 443 { 444 int ret, n; 445 446 if (!capable(CAP_SYS_ADMIN)) 447 return -EACCES; 448 449 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 450 if (!is_unrecognized_ioctl(ret)) 451 return ret; 452 if (get_user(n, (int __user *)arg)) 453 return -EFAULT; 454 set_device_ro(bdev, n); 455 return 0; 456 } 457 458 static int blkdev_getgeo(struct block_device *bdev, 459 struct hd_geometry __user *argp) 460 { 461 struct gendisk *disk = bdev->bd_disk; 462 struct hd_geometry geo; 463 int ret; 464 465 if (!argp) 466 return -EINVAL; 467 if (!disk->fops->getgeo) 468 return -ENOTTY; 469 470 /* 471 * We need to set the startsect first, the driver may 472 * want to override it. 473 */ 474 memset(&geo, 0, sizeof(geo)); 475 geo.start = get_start_sect(bdev); 476 ret = disk->fops->getgeo(bdev, &geo); 477 if (ret) 478 return ret; 479 if (copy_to_user(argp, &geo, sizeof(geo))) 480 return -EFAULT; 481 return 0; 482 } 483 484 /* set the logical block size */ 485 static int blkdev_bszset(struct block_device *bdev, fmode_t mode, 486 int __user *argp) 487 { 488 int ret, n; 489 490 if (!capable(CAP_SYS_ADMIN)) 491 return -EACCES; 492 if (!argp) 493 return -EINVAL; 494 if (get_user(n, argp)) 495 return -EFAULT; 496 497 if (!(mode & FMODE_EXCL)) { 498 bdgrab(bdev); 499 if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0) 500 return -EBUSY; 501 } 502 503 ret = set_blocksize(bdev, n); 504 if (!(mode & FMODE_EXCL)) 505 blkdev_put(bdev, mode | FMODE_EXCL); 506 return ret; 507 } 508 509 /* 510 * always keep this in sync with compat_blkdev_ioctl() 511 */ 512 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, 513 unsigned long arg) 514 { 515 void __user *argp = (void __user *)arg; 516 loff_t size; 517 unsigned int max_sectors; 518 519 switch (cmd) { 520 case BLKFLSBUF: 521 return blkdev_flushbuf(bdev, mode, cmd, arg); 522 case BLKROSET: 523 return blkdev_roset(bdev, mode, cmd, arg); 524 case BLKDISCARD: 525 return blk_ioctl_discard(bdev, mode, arg, 0); 526 case BLKSECDISCARD: 527 return blk_ioctl_discard(bdev, mode, arg, 528 BLKDEV_DISCARD_SECURE); 529 case BLKZEROOUT: 530 return blk_ioctl_zeroout(bdev, mode, arg); 531 case BLKREPORTZONE: 532 return blkdev_report_zones_ioctl(bdev, mode, cmd, arg); 533 case BLKRESETZONE: 534 return blkdev_reset_zones_ioctl(bdev, mode, cmd, arg); 535 case HDIO_GETGEO: 536 return blkdev_getgeo(bdev, argp); 537 case BLKRAGET: 538 case BLKFRAGET: 539 if (!arg) 540 return -EINVAL; 541 return put_long(arg, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512); 542 case BLKROGET: 543 return put_int(arg, bdev_read_only(bdev) != 0); 544 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */ 545 return put_int(arg, block_size(bdev)); 546 case BLKSSZGET: /* get block device logical block size */ 547 return put_int(arg, bdev_logical_block_size(bdev)); 548 case BLKPBSZGET: /* get block device physical block size */ 549 return put_uint(arg, bdev_physical_block_size(bdev)); 550 case BLKIOMIN: 551 return put_uint(arg, bdev_io_min(bdev)); 552 case BLKIOOPT: 553 return put_uint(arg, bdev_io_opt(bdev)); 554 case BLKALIGNOFF: 555 return put_int(arg, bdev_alignment_offset(bdev)); 556 case BLKDISCARDZEROES: 557 return put_uint(arg, 0); 558 case BLKSECTGET: 559 max_sectors = min_t(unsigned int, USHRT_MAX, 560 queue_max_sectors(bdev_get_queue(bdev))); 561 return put_ushort(arg, max_sectors); 562 case BLKROTATIONAL: 563 return put_ushort(arg, !blk_queue_nonrot(bdev_get_queue(bdev))); 564 case BLKRASET: 565 case BLKFRASET: 566 if(!capable(CAP_SYS_ADMIN)) 567 return -EACCES; 568 bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE; 569 return 0; 570 case BLKBSZSET: 571 return blkdev_bszset(bdev, mode, argp); 572 case BLKPG: 573 return blkpg_ioctl(bdev, argp); 574 case BLKRRPART: 575 return blkdev_reread_part(bdev); 576 case BLKGETSIZE: 577 size = i_size_read(bdev->bd_inode); 578 if ((size >> 9) > ~0UL) 579 return -EFBIG; 580 return put_ulong(arg, size >> 9); 581 case BLKGETSIZE64: 582 return put_u64(arg, i_size_read(bdev->bd_inode)); 583 case BLKTRACESTART: 584 case BLKTRACESTOP: 585 case BLKTRACESETUP: 586 case BLKTRACETEARDOWN: 587 return blk_trace_ioctl(bdev, cmd, argp); 588 case IOC_PR_REGISTER: 589 return blkdev_pr_register(bdev, argp); 590 case IOC_PR_RESERVE: 591 return blkdev_pr_reserve(bdev, argp); 592 case IOC_PR_RELEASE: 593 return blkdev_pr_release(bdev, argp); 594 case IOC_PR_PREEMPT: 595 return blkdev_pr_preempt(bdev, argp, false); 596 case IOC_PR_PREEMPT_ABORT: 597 return blkdev_pr_preempt(bdev, argp, true); 598 case IOC_PR_CLEAR: 599 return blkdev_pr_clear(bdev, argp); 600 default: 601 return __blkdev_driver_ioctl(bdev, mode, cmd, arg); 602 } 603 } 604 EXPORT_SYMBOL_GPL(blkdev_ioctl); 605