block/ioctl.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/capability.h>
   3 #include <linux/compat.h>
   4 #include <linux/blkdev.h>
   5 #include <linux/export.h>
   6 #include <linux/gfp.h>
   7 #include <linux/blkpg.h>
   8 #include <linux/hdreg.h>
   9 #include <linux/backing-dev.h>
  10 #include <linux/fs.h>
  11 #include <linux/blktrace_api.h>
  12 #include <linux/pr.h>
  13 #include <linux/uaccess.h>
  14 #include "blk.h"
  15
  16 static int blkpg_do_ioctl(struct block_device *bdev,
  17                           struct blkpg_partition __user *upart, int op)
  18 {
  19         struct blkpg_partition p;
  20         long long start, length;
  21
  22         if (!capable(CAP_SYS_ADMIN))
  23                 return -EACCES;
  24         if (copy_from_user(&p, upart, sizeof(struct blkpg_partition)))
  25                 return -EFAULT;
  26         if (bdev_is_partition(bdev))
  27                 return -EINVAL;
  28
  29         if (p.pno <= 0)
  30                 return -EINVAL;
  31
  32         if (op == BLKPG_DEL_PARTITION)
  33                 return bdev_del_partition(bdev, p.pno);
  34
  35         start = p.start >> SECTOR_SHIFT;
  36         length = p.length >> SECTOR_SHIFT;
  37
  38         switch (op) {
  39         case BLKPG_ADD_PARTITION:
  40                 /* check if partition is aligned to blocksize */
  41                 if (p.start & (bdev_logical_block_size(bdev) - 1))
  42                         return -EINVAL;
  43                 return bdev_add_partition(bdev, p.pno, start, length);
  44         case BLKPG_RESIZE_PARTITION:
  45                 return bdev_resize_partition(bdev, p.pno, start, length);
  46         default:
  47                 return -EINVAL;
  48         }
  49 }
  50
  51 static int blkpg_ioctl(struct block_device *bdev,
  52                        struct blkpg_ioctl_arg __user *arg)
  53 {
  54         struct blkpg_partition __user *udata;
  55         int op;
  56
  57         if (get_user(op, &arg->op) || get_user(udata, &arg->data))
  58                 return -EFAULT;
  59
  60         return blkpg_do_ioctl(bdev, udata, op);
  61 }
  62
  63 #ifdef CONFIG_COMPAT
  64 struct compat_blkpg_ioctl_arg {
  65         compat_int_t op;
  66         compat_int_t flags;
  67         compat_int_t datalen;
  68         compat_caddr_t data;
  69 };
  70
  71 static int compat_blkpg_ioctl(struct block_device *bdev,
  72                               struct compat_blkpg_ioctl_arg __user *arg)
  73 {
  74         compat_caddr_t udata;
  75         int op;
  76
  77         if (get_user(op, &arg->op) || get_user(udata, &arg->data))
  78                 return -EFAULT;
  79
  80         return blkpg_do_ioctl(bdev, compat_ptr(udata), op);
  81 }
  82 #endif
  83
  84 static int blkdev_reread_part(struct block_device *bdev, fmode_t mode)
  85 {
  86         struct block_device *tmp;
  87
  88         if (!disk_part_scan_enabled(bdev->bd_disk) || bdev_is_partition(bdev))
  89                 return -EINVAL;
  90         if (!capable(CAP_SYS_ADMIN))
  91                 return -EACCES;
  92         if (bdev->bd_part_count)
  93                 return -EBUSY;
  94
  95         /*
  96          * Reopen the device to revalidate the driver state and force a
  97          * partition rescan.
  98          */
  99         mode &= ~FMODE_EXCL;
 100         set_bit(GD_NEED_PART_SCAN, &bdev->bd_disk->state);
 101
 102         tmp = blkdev_get_by_dev(bdev->bd_dev, mode, NULL);
 103         if (IS_ERR(tmp))
 104                 return PTR_ERR(tmp);
 105         blkdev_put(tmp, mode);
 106         return 0;
 107 }
 108
 109 static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,
 110                 unsigned long arg, unsigned long flags)
 111 {
 112         uint64_t range[2];
 113         uint64_t start, len;
 114         struct request_queue *q = bdev_get_queue(bdev);
 115         int err;
 116
 117         if (!(mode & FMODE_WRITE))
 118                 return -EBADF;
 119
 120         if (!blk_queue_discard(q))
 121                 return -EOPNOTSUPP;
 122
 123         if (copy_from_user(range, (void __user *)arg, sizeof(range)))
 124                 return -EFAULT;
 125
 126         start = range[0];
 127         len = range[1];
 128
 129         if (start & 511)
 130                 return -EINVAL;
 131         if (len & 511)
 132                 return -EINVAL;
 133
 134         if (start + len > i_size_read(bdev->bd_inode))
 135                 return -EINVAL;
 136
 137         err = truncate_bdev_range(bdev, mode, start, start + len - 1);
 138         if (err)
 139                 return err;
 140
 141         return blkdev_issue_discard(bdev, start >> 9, len >> 9,
 142                                     GFP_KERNEL, flags);
 143 }
 144
 145 static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode,
 146                 unsigned long arg)
 147 {
 148         uint64_t range[2];
 149         uint64_t start, end, len;
 150         int err;
 151
 152         if (!(mode & FMODE_WRITE))
 153                 return -EBADF;
 154
 155         if (copy_from_user(range, (void __user *)arg, sizeof(range)))
 156                 return -EFAULT;
 157
 158         start = range[0];
 159         len = range[1];
 160         end = start + len - 1;
 161
 162         if (start & 511)
 163                 return -EINVAL;
 164         if (len & 511)
 165                 return -EINVAL;
 166         if (end >= (uint64_t)i_size_read(bdev->bd_inode))
 167                 return -EINVAL;
 168         if (end < start)
 169                 return -EINVAL;
 170
 171         /* Invalidate the page cache, including dirty pages */
 172         err = truncate_bdev_range(bdev, mode, start, end);
 173         if (err)
 174                 return err;
 175
 176         return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,
 177                         BLKDEV_ZERO_NOUNMAP);
 178 }
 179
 180 static int put_ushort(unsigned short __user *argp, unsigned short val)
 181 {
 182         return put_user(val, argp);
 183 }
 184
 185 static int put_int(int __user *argp, int val)
 186 {
 187         return put_user(val, argp);
 188 }
 189
 190 static int put_uint(unsigned int __user *argp, unsigned int val)
 191 {
 192         return put_user(val, argp);
 193 }
 194
 195 static int put_long(long __user *argp, long val)
 196 {
 197         return put_user(val, argp);
 198 }
 199
 200 static int put_ulong(unsigned long __user *argp, unsigned long val)
 201 {
 202         return put_user(val, argp);
 203 }
 204
 205 static int put_u64(u64 __user *argp, u64 val)
 206 {
 207         return put_user(val, argp);
 208 }
 209
 210 #ifdef CONFIG_COMPAT
 211 static int compat_put_long(compat_long_t __user *argp, long val)
 212 {
 213         return put_user(val, argp);
 214 }
 215
 216 static int compat_put_ulong(compat_ulong_t __user *argp, compat_ulong_t val)
 217 {
 218         return put_user(val, argp);
 219 }
 220 #endif
 221
 222 #ifdef CONFIG_COMPAT
 223 /*
 224  * This is the equivalent of compat_ptr_ioctl(), to be used by block
 225  * drivers that implement only commands that are completely compatible
 226  * between 32-bit and 64-bit user space
 227  */
 228 int blkdev_compat_ptr_ioctl(struct block_device *bdev, fmode_t mode,
 229                         unsigned cmd, unsigned long arg)
 230 {
 231         struct gendisk *disk = bdev->bd_disk;
 232
 233         if (disk->fops->ioctl)
 234                 return disk->fops->ioctl(bdev, mode, cmd,
 235                                          (unsigned long)compat_ptr(arg));
 236
 237         return -ENOIOCTLCMD;
 238 }
 239 EXPORT_SYMBOL(blkdev_compat_ptr_ioctl);
 240 #endif
 241
 242 static int blkdev_pr_register(struct block_device *bdev,
 243                 struct pr_registration __user *arg)
 244 {
 245         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 246         struct pr_registration reg;
 247
 248         if (!capable(CAP_SYS_ADMIN))
 249                 return -EPERM;
 250         if (!ops || !ops->pr_register)
 251                 return -EOPNOTSUPP;
 252         if (copy_from_user(&reg, arg, sizeof(reg)))
 253                 return -EFAULT;
 254
 255         if (reg.flags & ~PR_FL_IGNORE_KEY)
 256                 return -EOPNOTSUPP;
 257         return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);
 258 }
 259
 260 static int blkdev_pr_reserve(struct block_device *bdev,
 261                 struct pr_reservation __user *arg)
 262 {
 263         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 264         struct pr_reservation rsv;
 265
 266         if (!capable(CAP_SYS_ADMIN))
 267                 return -EPERM;
 268         if (!ops || !ops->pr_reserve)
 269                 return -EOPNOTSUPP;
 270         if (copy_from_user(&rsv, arg, sizeof(rsv)))
 271                 return -EFAULT;
 272
 273         if (rsv.flags & ~PR_FL_IGNORE_KEY)
 274                 return -EOPNOTSUPP;
 275         return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);
 276 }
 277
 278 static int blkdev_pr_release(struct block_device *bdev,
 279                 struct pr_reservation __user *arg)
 280 {
 281         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 282         struct pr_reservation rsv;
 283
 284         if (!capable(CAP_SYS_ADMIN))
 285                 return -EPERM;
 286         if (!ops || !ops->pr_release)
 287                 return -EOPNOTSUPP;
 288         if (copy_from_user(&rsv, arg, sizeof(rsv)))
 289                 return -EFAULT;
 290
 291         if (rsv.flags)
 292                 return -EOPNOTSUPP;
 293         return ops->pr_release(bdev, rsv.key, rsv.type);
 294 }
 295
 296 static int blkdev_pr_preempt(struct block_device *bdev,
 297                 struct pr_preempt __user *arg, bool abort)
 298 {
 299         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 300         struct pr_preempt p;
 301
 302         if (!capable(CAP_SYS_ADMIN))
 303                 return -EPERM;
 304         if (!ops || !ops->pr_preempt)
 305                 return -EOPNOTSUPP;
 306         if (copy_from_user(&p, arg, sizeof(p)))
 307                 return -EFAULT;
 308
 309         if (p.flags)
 310                 return -EOPNOTSUPP;
 311         return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);
 312 }
 313
 314 static int blkdev_pr_clear(struct block_device *bdev,
 315                 struct pr_clear __user *arg)
 316 {
 317         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 318         struct pr_clear c;
 319
 320         if (!capable(CAP_SYS_ADMIN))
 321                 return -EPERM;
 322         if (!ops || !ops->pr_clear)
 323                 return -EOPNOTSUPP;
 324         if (copy_from_user(&c, arg, sizeof(c)))
 325                 return -EFAULT;
 326
 327         if (c.flags)
 328                 return -EOPNOTSUPP;
 329         return ops->pr_clear(bdev, c.key);
 330 }
 331
 332 static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode,
 333                 unsigned cmd, unsigned long arg)
 334 {
 335         if (!capable(CAP_SYS_ADMIN))
 336                 return -EACCES;
 337         fsync_bdev(bdev);
 338         invalidate_bdev(bdev);
 339         return 0;
 340 }
 341
 342 static int blkdev_roset(struct block_device *bdev, fmode_t mode,
 343                 unsigned cmd, unsigned long arg)
 344 {
 345         int ret, n;
 346
 347         if (!capable(CAP_SYS_ADMIN))
 348                 return -EACCES;
 349
 350         if (get_user(n, (int __user *)arg))
 351                 return -EFAULT;
 352         if (bdev->bd_disk->fops->set_read_only) {
 353                 ret = bdev->bd_disk->fops->set_read_only(bdev, n);
 354                 if (ret)
 355                         return ret;
 356         }
 357         bdev->bd_read_only = n;
 358         return 0;
 359 }
 360
 361 static int blkdev_getgeo(struct block_device *bdev,
 362                 struct hd_geometry __user *argp)
 363 {
 364         struct gendisk *disk = bdev->bd_disk;
 365         struct hd_geometry geo;
 366         int ret;
 367
 368         if (!argp)
 369                 return -EINVAL;
 370         if (!disk->fops->getgeo)
 371                 return -ENOTTY;
 372
 373         /*
 374          * We need to set the startsect first, the driver may
 375          * want to override it.
 376          */
 377         memset(&geo, 0, sizeof(geo));
 378         geo.start = get_start_sect(bdev);
 379         ret = disk->fops->getgeo(bdev, &geo);
 380         if (ret)
 381                 return ret;
 382         if (copy_to_user(argp, &geo, sizeof(geo)))
 383                 return -EFAULT;
 384         return 0;
 385 }
 386
 387 #ifdef CONFIG_COMPAT
 388 struct compat_hd_geometry {
 389         unsigned char heads;
 390         unsigned char sectors;
 391         unsigned short cylinders;
 392         u32 start;
 393 };
 394
 395 static int compat_hdio_getgeo(struct block_device *bdev,
 396                               struct compat_hd_geometry __user *ugeo)
 397 {
 398         struct gendisk *disk = bdev->bd_disk;
 399         struct hd_geometry geo;
 400         int ret;
 401
 402         if (!ugeo)
 403                 return -EINVAL;
 404         if (!disk->fops->getgeo)
 405                 return -ENOTTY;
 406
 407         memset(&geo, 0, sizeof(geo));
 408         /*
 409          * We need to set the startsect first, the driver may
 410          * want to override it.
 411          */
 412         geo.start = get_start_sect(bdev);
 413         ret = disk->fops->getgeo(bdev, &geo);
 414         if (ret)
 415                 return ret;
 416
 417         ret = copy_to_user(ugeo, &geo, 4);
 418         ret |= put_user(geo.start, &ugeo->start);
 419         if (ret)
 420                 ret = -EFAULT;
 421
 422         return ret;
 423 }
 424 #endif
 425
 426 /* set the logical block size */
 427 static int blkdev_bszset(struct block_device *bdev, fmode_t mode,
 428                 int __user *argp)
 429 {
 430         int ret, n;
 431
 432         if (!capable(CAP_SYS_ADMIN))
 433                 return -EACCES;
 434         if (!argp)
 435                 return -EINVAL;
 436         if (get_user(n, argp))
 437                 return -EFAULT;
 438
 439         if (mode & FMODE_EXCL)
 440                 return set_blocksize(bdev, n);
 441
 442         if (IS_ERR(blkdev_get_by_dev(bdev->bd_dev, mode | FMODE_EXCL, &bdev)))
 443                 return -EBUSY;
 444         ret = set_blocksize(bdev, n);
 445         blkdev_put(bdev, mode | FMODE_EXCL);
 446
 447         return ret;
 448 }
 449
 450 /*
 451  * Common commands that are handled the same way on native and compat
 452  * user space. Note the separate arg/argp parameters that are needed
 453  * to deal with the compat_ptr() conversion.
 454  */
 455 static int blkdev_common_ioctl(struct block_device *bdev, fmode_t mode,
 456                                 unsigned cmd, unsigned long arg, void __user *argp)
 457 {
 458         unsigned int max_sectors;
 459
 460         switch (cmd) {
 461         case BLKFLSBUF:
 462                 return blkdev_flushbuf(bdev, mode, cmd, arg);
 463         case BLKROSET:
 464                 return blkdev_roset(bdev, mode, cmd, arg);
 465         case BLKDISCARD:
 466                 return blk_ioctl_discard(bdev, mode, arg, 0);
 467         case BLKSECDISCARD:
 468                 return blk_ioctl_discard(bdev, mode, arg,
 469                                 BLKDEV_DISCARD_SECURE);
 470         case BLKZEROOUT:
 471                 return blk_ioctl_zeroout(bdev, mode, arg);
 472         case BLKREPORTZONE:
 473                 return blkdev_report_zones_ioctl(bdev, mode, cmd, arg);
 474         case BLKRESETZONE:
 475         case BLKOPENZONE:
 476         case BLKCLOSEZONE:
 477         case BLKFINISHZONE:
 478                 return blkdev_zone_mgmt_ioctl(bdev, mode, cmd, arg);
 479         case BLKGETZONESZ:
 480                 return put_uint(argp, bdev_zone_sectors(bdev));
 481         case BLKGETNRZONES:
 482                 return put_uint(argp, blkdev_nr_zones(bdev->bd_disk));
 483         case BLKROGET:
 484                 return put_int(argp, bdev_read_only(bdev) != 0);
 485         case BLKSSZGET: /* get block device logical block size */
 486                 return put_int(argp, bdev_logical_block_size(bdev));
 487         case BLKPBSZGET: /* get block device physical block size */
 488                 return put_uint(argp, bdev_physical_block_size(bdev));
 489         case BLKIOMIN:
 490                 return put_uint(argp, bdev_io_min(bdev));
 491         case BLKIOOPT:
 492                 return put_uint(argp, bdev_io_opt(bdev));
 493         case BLKALIGNOFF:
 494                 return put_int(argp, bdev_alignment_offset(bdev));
 495         case BLKDISCARDZEROES:
 496                 return put_uint(argp, 0);
 497         case BLKSECTGET:
 498                 max_sectors = min_t(unsigned int, USHRT_MAX,
 499                                     queue_max_sectors(bdev_get_queue(bdev)));
 500                 return put_ushort(argp, max_sectors);
 501         case BLKROTATIONAL:
 502                 return put_ushort(argp, !blk_queue_nonrot(bdev_get_queue(bdev)));
 503         case BLKRASET:
 504         case BLKFRASET:
 505                 if(!capable(CAP_SYS_ADMIN))
 506                         return -EACCES;
 507                 bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE;
 508                 return 0;
 509         case BLKRRPART:
 510                 return blkdev_reread_part(bdev, mode);
 511         case BLKTRACESTART:
 512         case BLKTRACESTOP:
 513         case BLKTRACETEARDOWN:
 514                 return blk_trace_ioctl(bdev, cmd, argp);
 515         case IOC_PR_REGISTER:
 516                 return blkdev_pr_register(bdev, argp);
 517         case IOC_PR_RESERVE:
 518                 return blkdev_pr_reserve(bdev, argp);
 519         case IOC_PR_RELEASE:
 520                 return blkdev_pr_release(bdev, argp);
 521         case IOC_PR_PREEMPT:
 522                 return blkdev_pr_preempt(bdev, argp, false);
 523         case IOC_PR_PREEMPT_ABORT:
 524                 return blkdev_pr_preempt(bdev, argp, true);
 525         case IOC_PR_CLEAR:
 526                 return blkdev_pr_clear(bdev, argp);
 527         default:
 528                 return -ENOIOCTLCMD;
 529         }
 530 }
 531
 532 /*
 533  * Always keep this in sync with compat_blkdev_ioctl()
 534  * to handle all incompatible commands in both functions.
 535  *
 536  * New commands must be compatible and go into blkdev_common_ioctl
 537  */
 538 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 539                         unsigned long arg)
 540 {
 541         int ret;
 542         loff_t size;
 543         void __user *argp = (void __user *)arg;
 544
 545         switch (cmd) {
 546         /* These need separate implementations for the data structure */
 547         case HDIO_GETGEO:
 548                 return blkdev_getgeo(bdev, argp);
 549         case BLKPG:
 550                 return blkpg_ioctl(bdev, argp);
 551
 552         /* Compat mode returns 32-bit data instead of 'long' */
 553         case BLKRAGET:
 554         case BLKFRAGET:
 555                 if (!argp)
 556                         return -EINVAL;
 557                 return put_long(argp, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512);
 558         case BLKGETSIZE:
 559                 size = i_size_read(bdev->bd_inode);
 560                 if ((size >> 9) > ~0UL)
 561                         return -EFBIG;
 562                 return put_ulong(argp, size >> 9);
 563
 564         /* The data is compatible, but the command number is different */
 565         case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
 566                 return put_int(argp, block_size(bdev));
 567         case BLKBSZSET:
 568                 return blkdev_bszset(bdev, mode, argp);
 569         case BLKGETSIZE64:
 570                 return put_u64(argp, i_size_read(bdev->bd_inode));
 571
 572         /* Incompatible alignment on i386 */
 573         case BLKTRACESETUP:
 574                 return blk_trace_ioctl(bdev, cmd, argp);
 575         default:
 576                 break;
 577         }
 578
 579         ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
 580         if (ret != -ENOIOCTLCMD)
 581                 return ret;
 582
 583         if (!bdev->bd_disk->fops->ioctl)
 584                 return -ENOTTY;
 585         return bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
 586 }
 587 EXPORT_SYMBOL_GPL(blkdev_ioctl); /* for /dev/raw */
 588
 589 #ifdef CONFIG_COMPAT
 590
 591 #define BLKBSZGET_32            _IOR(0x12, 112, int)
 592 #define BLKBSZSET_32            _IOW(0x12, 113, int)
 593 #define BLKGETSIZE64_32         _IOR(0x12, 114, int)
 594
 595 /* Most of the generic ioctls are handled in the normal fallback path.
 596    This assumes the blkdev's low level compat_ioctl always returns
 597    ENOIOCTLCMD for unknown ioctls. */
 598 long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 599 {
 600         int ret;
 601         void __user *argp = compat_ptr(arg);
 602         struct block_device *bdev = I_BDEV(file->f_mapping->host);
 603         struct gendisk *disk = bdev->bd_disk;
 604         fmode_t mode = file->f_mode;
 605         loff_t size;
 606
 607         /*
 608          * O_NDELAY can be altered using fcntl(.., F_SETFL, ..), so we have
 609          * to updated it before every ioctl.
 610          */
 611         if (file->f_flags & O_NDELAY)
 612                 mode |= FMODE_NDELAY;
 613         else
 614                 mode &= ~FMODE_NDELAY;
 615
 616         switch (cmd) {
 617         /* These need separate implementations for the data structure */
 618         case HDIO_GETGEO:
 619                 return compat_hdio_getgeo(bdev, argp);
 620         case BLKPG:
 621                 return compat_blkpg_ioctl(bdev, argp);
 622
 623         /* Compat mode returns 32-bit data instead of 'long' */
 624         case BLKRAGET:
 625         case BLKFRAGET:
 626                 if (!argp)
 627                         return -EINVAL;
 628                 return compat_put_long(argp,
 629                                (bdev->bd_bdi->ra_pages * PAGE_SIZE) / 512);
 630         case BLKGETSIZE:
 631                 size = i_size_read(bdev->bd_inode);
 632                 if ((size >> 9) > ~0UL)
 633                         return -EFBIG;
 634                 return compat_put_ulong(argp, size >> 9);
 635
 636         /* The data is compatible, but the command number is different */
 637         case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */
 638                 return put_int(argp, bdev_logical_block_size(bdev));
 639         case BLKBSZSET_32:
 640                 return blkdev_bszset(bdev, mode, argp);
 641         case BLKGETSIZE64_32:
 642                 return put_u64(argp, i_size_read(bdev->bd_inode));
 643
 644         /* Incompatible alignment on i386 */
 645         case BLKTRACESETUP32:
 646                 return blk_trace_ioctl(bdev, cmd, argp);
 647         default:
 648                 break;
 649         }
 650
 651         ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
 652         if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl)
 653                 ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg);
 654
 655         return ret;
 656 }
 657 #endif