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 <linux/pagemap.h>
  15 #include <linux/io_uring/cmd.h>
  16 #include <uapi/linux/blkdev.h>
  17 #include "blk.h"
  18
  19 static int blkpg_do_ioctl(struct block_device *bdev,
  20                           struct blkpg_partition __user *upart, int op)
  21 {
  22         struct gendisk *disk = bdev->bd_disk;
  23         struct blkpg_partition p;
  24         sector_t start, length, capacity, end;
  25
  26         if (!capable(CAP_SYS_ADMIN))
  27                 return -EACCES;
  28         if (copy_from_user(&p, upart, sizeof(struct blkpg_partition)))
  29                 return -EFAULT;
  30         if (bdev_is_partition(bdev))
  31                 return -EINVAL;
  32
  33         if (p.pno <= 0)
  34                 return -EINVAL;
  35
  36         if (op == BLKPG_DEL_PARTITION)
  37                 return bdev_del_partition(disk, p.pno);
  38
  39         if (p.start < 0 || p.length <= 0 || LLONG_MAX - p.length < p.start)
  40                 return -EINVAL;
  41         /* Check that the partition is aligned to the block size */
  42         if (!IS_ALIGNED(p.start | p.length, bdev_logical_block_size(bdev)))
  43                 return -EINVAL;
  44
  45         start = p.start >> SECTOR_SHIFT;
  46         length = p.length >> SECTOR_SHIFT;
  47         capacity = get_capacity(disk);
  48
  49         if (check_add_overflow(start, length, &end))
  50                 return -EINVAL;
  51
  52         if (start >= capacity || end > capacity)
  53                 return -EINVAL;
  54
  55         switch (op) {
  56         case BLKPG_ADD_PARTITION:
  57                 return bdev_add_partition(disk, p.pno, start, length);
  58         case BLKPG_RESIZE_PARTITION:
  59                 return bdev_resize_partition(disk, p.pno, start, length);
  60         default:
  61                 return -EINVAL;
  62         }
  63 }
  64
  65 static int blkpg_ioctl(struct block_device *bdev,
  66                        struct blkpg_ioctl_arg __user *arg)
  67 {
  68         struct blkpg_partition __user *udata;
  69         int op;
  70
  71         if (get_user(op, &arg->op) || get_user(udata, &arg->data))
  72                 return -EFAULT;
  73
  74         return blkpg_do_ioctl(bdev, udata, op);
  75 }
  76
  77 #ifdef CONFIG_COMPAT
  78 struct compat_blkpg_ioctl_arg {
  79         compat_int_t op;
  80         compat_int_t flags;
  81         compat_int_t datalen;
  82         compat_caddr_t data;
  83 };
  84
  85 static int compat_blkpg_ioctl(struct block_device *bdev,
  86                               struct compat_blkpg_ioctl_arg __user *arg)
  87 {
  88         compat_caddr_t udata;
  89         int op;
  90
  91         if (get_user(op, &arg->op) || get_user(udata, &arg->data))
  92                 return -EFAULT;
  93
  94         return blkpg_do_ioctl(bdev, compat_ptr(udata), op);
  95 }
  96 #endif
  97
  98 /*
  99  * Check that [start, start + len) is a valid range from the block device's
 100  * perspective, including verifying that it can be correctly translated into
 101  * logical block addresses.
 102  */
 103 static int blk_validate_byte_range(struct block_device *bdev,
 104                                    uint64_t start, uint64_t len)
 105 {
 106         unsigned int bs_mask = bdev_logical_block_size(bdev) - 1;
 107         uint64_t end;
 108
 109         if ((start | len) & bs_mask)
 110                 return -EINVAL;
 111         if (!len)
 112                 return -EINVAL;
 113         if (check_add_overflow(start, len, &end) || end > bdev_nr_bytes(bdev))
 114                 return -EINVAL;
 115
 116         return 0;
 117 }
 118
 119 static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
 120                 unsigned long arg)
 121 {
 122         uint64_t range[2], start, len;
 123         struct bio *prev = NULL, *bio;
 124         sector_t sector, nr_sects;
 125         struct blk_plug plug;
 126         int err;
 127
 128         if (copy_from_user(range, (void __user *)arg, sizeof(range)))
 129                 return -EFAULT;
 130         start = range[0];
 131         len = range[1];
 132
 133         if (!bdev_max_discard_sectors(bdev))
 134                 return -EOPNOTSUPP;
 135
 136         if (!(mode & BLK_OPEN_WRITE))
 137                 return -EBADF;
 138         if (bdev_read_only(bdev))
 139                 return -EPERM;
 140         err = blk_validate_byte_range(bdev, start, len);
 141         if (err)
 142                 return err;
 143
 144         filemap_invalidate_lock(bdev->bd_mapping);
 145         err = truncate_bdev_range(bdev, mode, start, start + len - 1);
 146         if (err)
 147                 goto fail;
 148
 149         sector = start >> SECTOR_SHIFT;
 150         nr_sects = len >> SECTOR_SHIFT;
 151
 152         blk_start_plug(&plug);
 153         while (1) {
 154                 if (fatal_signal_pending(current)) {
 155                         if (prev)
 156                                 bio_await_chain(prev);
 157                         err = -EINTR;
 158                         goto out_unplug;
 159                 }
 160                 bio = blk_alloc_discard_bio(bdev, &sector, &nr_sects,
 161                                 GFP_KERNEL);
 162                 if (!bio)
 163                         break;
 164                 prev = bio_chain_and_submit(prev, bio);
 165         }
 166         if (prev) {
 167                 err = submit_bio_wait(prev);
 168                 if (err == -EOPNOTSUPP)
 169                         err = 0;
 170                 bio_put(prev);
 171         }
 172 out_unplug:
 173         blk_finish_plug(&plug);
 174 fail:
 175         filemap_invalidate_unlock(bdev->bd_mapping);
 176         return err;
 177 }
 178
 179 static int blk_ioctl_secure_erase(struct block_device *bdev, blk_mode_t mode,
 180                 void __user *argp)
 181 {
 182         uint64_t start, len, end;
 183         uint64_t range[2];
 184         int err;
 185
 186         if (!(mode & BLK_OPEN_WRITE))
 187                 return -EBADF;
 188         if (!bdev_max_secure_erase_sectors(bdev))
 189                 return -EOPNOTSUPP;
 190         if (copy_from_user(range, argp, sizeof(range)))
 191                 return -EFAULT;
 192
 193         start = range[0];
 194         len = range[1];
 195         if ((start & 511) || (len & 511))
 196                 return -EINVAL;
 197         if (check_add_overflow(start, len, &end) ||
 198             end > bdev_nr_bytes(bdev))
 199                 return -EINVAL;
 200
 201         filemap_invalidate_lock(bdev->bd_mapping);
 202         err = truncate_bdev_range(bdev, mode, start, end - 1);
 203         if (!err)
 204                 err = blkdev_issue_secure_erase(bdev, start >> 9, len >> 9,
 205                                                 GFP_KERNEL);
 206         filemap_invalidate_unlock(bdev->bd_mapping);
 207         return err;
 208 }
 209
 210
 211 static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
 212                 unsigned long arg)
 213 {
 214         uint64_t range[2];
 215         uint64_t start, end, len;
 216         int err;
 217
 218         if (!(mode & BLK_OPEN_WRITE))
 219                 return -EBADF;
 220
 221         if (copy_from_user(range, (void __user *)arg, sizeof(range)))
 222                 return -EFAULT;
 223
 224         start = range[0];
 225         len = range[1];
 226         end = start + len - 1;
 227
 228         if (start & 511)
 229                 return -EINVAL;
 230         if (len & 511)
 231                 return -EINVAL;
 232         if (end >= (uint64_t)bdev_nr_bytes(bdev))
 233                 return -EINVAL;
 234         if (end < start)
 235                 return -EINVAL;
 236
 237         /* Invalidate the page cache, including dirty pages */
 238         filemap_invalidate_lock(bdev->bd_mapping);
 239         err = truncate_bdev_range(bdev, mode, start, end);
 240         if (err)
 241                 goto fail;
 242
 243         err = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,
 244                                    BLKDEV_ZERO_NOUNMAP | BLKDEV_ZERO_KILLABLE);
 245
 246 fail:
 247         filemap_invalidate_unlock(bdev->bd_mapping);
 248         return err;
 249 }
 250
 251 static int put_ushort(unsigned short __user *argp, unsigned short val)
 252 {
 253         return put_user(val, argp);
 254 }
 255
 256 static int put_int(int __user *argp, int val)
 257 {
 258         return put_user(val, argp);
 259 }
 260
 261 static int put_uint(unsigned int __user *argp, unsigned int val)
 262 {
 263         return put_user(val, argp);
 264 }
 265
 266 static int put_long(long __user *argp, long val)
 267 {
 268         return put_user(val, argp);
 269 }
 270
 271 static int put_ulong(unsigned long __user *argp, unsigned long val)
 272 {
 273         return put_user(val, argp);
 274 }
 275
 276 static int put_u64(u64 __user *argp, u64 val)
 277 {
 278         return put_user(val, argp);
 279 }
 280
 281 #ifdef CONFIG_COMPAT
 282 static int compat_put_long(compat_long_t __user *argp, long val)
 283 {
 284         return put_user(val, argp);
 285 }
 286
 287 static int compat_put_ulong(compat_ulong_t __user *argp, compat_ulong_t val)
 288 {
 289         return put_user(val, argp);
 290 }
 291 #endif
 292
 293 #ifdef CONFIG_COMPAT
 294 /*
 295  * This is the equivalent of compat_ptr_ioctl(), to be used by block
 296  * drivers that implement only commands that are completely compatible
 297  * between 32-bit and 64-bit user space
 298  */
 299 int blkdev_compat_ptr_ioctl(struct block_device *bdev, blk_mode_t mode,
 300                         unsigned cmd, unsigned long arg)
 301 {
 302         struct gendisk *disk = bdev->bd_disk;
 303
 304         if (disk->fops->ioctl)
 305                 return disk->fops->ioctl(bdev, mode, cmd,
 306                                          (unsigned long)compat_ptr(arg));
 307
 308         return -ENOIOCTLCMD;
 309 }
 310 EXPORT_SYMBOL(blkdev_compat_ptr_ioctl);
 311 #endif
 312
 313 static bool blkdev_pr_allowed(struct block_device *bdev, blk_mode_t mode)
 314 {
 315         /* no sense to make reservations for partitions */
 316         if (bdev_is_partition(bdev))
 317                 return false;
 318
 319         if (capable(CAP_SYS_ADMIN))
 320                 return true;
 321         /*
 322          * Only allow unprivileged reservations if the file descriptor is open
 323          * for writing.
 324          */
 325         return mode & BLK_OPEN_WRITE;
 326 }
 327
 328 static int blkdev_pr_register(struct block_device *bdev, blk_mode_t mode,
 329                 struct pr_registration __user *arg)
 330 {
 331         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 332         struct pr_registration reg;
 333
 334         if (!blkdev_pr_allowed(bdev, mode))
 335                 return -EPERM;
 336         if (!ops || !ops->pr_register)
 337                 return -EOPNOTSUPP;
 338         if (copy_from_user(&reg, arg, sizeof(reg)))
 339                 return -EFAULT;
 340
 341         if (reg.flags & ~PR_FL_IGNORE_KEY)
 342                 return -EOPNOTSUPP;
 343         return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);
 344 }
 345
 346 static int blkdev_pr_reserve(struct block_device *bdev, blk_mode_t mode,
 347                 struct pr_reservation __user *arg)
 348 {
 349         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 350         struct pr_reservation rsv;
 351
 352         if (!blkdev_pr_allowed(bdev, mode))
 353                 return -EPERM;
 354         if (!ops || !ops->pr_reserve)
 355                 return -EOPNOTSUPP;
 356         if (copy_from_user(&rsv, arg, sizeof(rsv)))
 357                 return -EFAULT;
 358
 359         if (rsv.flags & ~PR_FL_IGNORE_KEY)
 360                 return -EOPNOTSUPP;
 361         return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);
 362 }
 363
 364 static int blkdev_pr_release(struct block_device *bdev, blk_mode_t mode,
 365                 struct pr_reservation __user *arg)
 366 {
 367         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 368         struct pr_reservation rsv;
 369
 370         if (!blkdev_pr_allowed(bdev, mode))
 371                 return -EPERM;
 372         if (!ops || !ops->pr_release)
 373                 return -EOPNOTSUPP;
 374         if (copy_from_user(&rsv, arg, sizeof(rsv)))
 375                 return -EFAULT;
 376
 377         if (rsv.flags)
 378                 return -EOPNOTSUPP;
 379         return ops->pr_release(bdev, rsv.key, rsv.type);
 380 }
 381
 382 static int blkdev_pr_preempt(struct block_device *bdev, blk_mode_t mode,
 383                 struct pr_preempt __user *arg, bool abort)
 384 {
 385         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 386         struct pr_preempt p;
 387
 388         if (!blkdev_pr_allowed(bdev, mode))
 389                 return -EPERM;
 390         if (!ops || !ops->pr_preempt)
 391                 return -EOPNOTSUPP;
 392         if (copy_from_user(&p, arg, sizeof(p)))
 393                 return -EFAULT;
 394
 395         if (p.flags)
 396                 return -EOPNOTSUPP;
 397         return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);
 398 }
 399
 400 static int blkdev_pr_clear(struct block_device *bdev, blk_mode_t mode,
 401                 struct pr_clear __user *arg)
 402 {
 403         const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
 404         struct pr_clear c;
 405
 406         if (!blkdev_pr_allowed(bdev, mode))
 407                 return -EPERM;
 408         if (!ops || !ops->pr_clear)
 409                 return -EOPNOTSUPP;
 410         if (copy_from_user(&c, arg, sizeof(c)))
 411                 return -EFAULT;
 412
 413         if (c.flags)
 414                 return -EOPNOTSUPP;
 415         return ops->pr_clear(bdev, c.key);
 416 }
 417
 418 static int blkdev_flushbuf(struct block_device *bdev, unsigned cmd,
 419                 unsigned long arg)
 420 {
 421         if (!capable(CAP_SYS_ADMIN))
 422                 return -EACCES;
 423
 424         mutex_lock(&bdev->bd_holder_lock);
 425         if (bdev->bd_holder_ops && bdev->bd_holder_ops->sync)
 426                 bdev->bd_holder_ops->sync(bdev);
 427         else {
 428                 mutex_unlock(&bdev->bd_holder_lock);
 429                 sync_blockdev(bdev);
 430         }
 431
 432         invalidate_bdev(bdev);
 433         return 0;
 434 }
 435
 436 static int blkdev_roset(struct block_device *bdev, unsigned cmd,
 437                 unsigned long arg)
 438 {
 439         int ret, n;
 440
 441         if (!capable(CAP_SYS_ADMIN))
 442                 return -EACCES;
 443
 444         if (get_user(n, (int __user *)arg))
 445                 return -EFAULT;
 446         if (bdev->bd_disk->fops->set_read_only) {
 447                 ret = bdev->bd_disk->fops->set_read_only(bdev, n);
 448                 if (ret)
 449                         return ret;
 450         }
 451         if (n)
 452                 bdev_set_flag(bdev, BD_READ_ONLY);
 453         else
 454                 bdev_clear_flag(bdev, BD_READ_ONLY);
 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 #ifdef CONFIG_COMPAT
 485 struct compat_hd_geometry {
 486         unsigned char heads;
 487         unsigned char sectors;
 488         unsigned short cylinders;
 489         u32 start;
 490 };
 491
 492 static int compat_hdio_getgeo(struct block_device *bdev,
 493                               struct compat_hd_geometry __user *ugeo)
 494 {
 495         struct gendisk *disk = bdev->bd_disk;
 496         struct hd_geometry geo;
 497         int ret;
 498
 499         if (!ugeo)
 500                 return -EINVAL;
 501         if (!disk->fops->getgeo)
 502                 return -ENOTTY;
 503
 504         memset(&geo, 0, sizeof(geo));
 505         /*
 506          * We need to set the startsect first, the driver may
 507          * want to override it.
 508          */
 509         geo.start = get_start_sect(bdev);
 510         ret = disk->fops->getgeo(bdev, &geo);
 511         if (ret)
 512                 return ret;
 513
 514         ret = copy_to_user(ugeo, &geo, 4);
 515         ret |= put_user(geo.start, &ugeo->start);
 516         if (ret)
 517                 ret = -EFAULT;
 518
 519         return ret;
 520 }
 521 #endif
 522
 523 /* set the logical block size */
 524 static int blkdev_bszset(struct file *file, blk_mode_t mode,
 525                 int __user *argp)
 526 {
 527         // this one might be file_inode(file)->i_rdev - a rare valid
 528         // use of file_inode() for those.
 529         dev_t dev = I_BDEV(file->f_mapping->host)->bd_dev;
 530         struct file *excl_file;
 531         int ret, n;
 532
 533         if (!capable(CAP_SYS_ADMIN))
 534                 return -EACCES;
 535         if (!argp)
 536                 return -EINVAL;
 537         if (get_user(n, argp))
 538                 return -EFAULT;
 539
 540         if (mode & BLK_OPEN_EXCL)
 541                 return set_blocksize(file, n);
 542
 543         excl_file = bdev_file_open_by_dev(dev, mode, &dev, NULL);
 544         if (IS_ERR(excl_file))
 545                 return -EBUSY;
 546         ret = set_blocksize(excl_file, n);
 547         fput(excl_file);
 548         return ret;
 549 }
 550
 551 /*
 552  * Common commands that are handled the same way on native and compat
 553  * user space. Note the separate arg/argp parameters that are needed
 554  * to deal with the compat_ptr() conversion.
 555  */
 556 static int blkdev_common_ioctl(struct block_device *bdev, blk_mode_t mode,
 557                                unsigned int cmd, unsigned long arg,
 558                                void __user *argp)
 559 {
 560         unsigned int max_sectors;
 561
 562         switch (cmd) {
 563         case BLKFLSBUF:
 564                 return blkdev_flushbuf(bdev, cmd, arg);
 565         case BLKROSET:
 566                 return blkdev_roset(bdev, cmd, arg);
 567         case BLKDISCARD:
 568                 return blk_ioctl_discard(bdev, mode, arg);
 569         case BLKSECDISCARD:
 570                 return blk_ioctl_secure_erase(bdev, mode, argp);
 571         case BLKZEROOUT:
 572                 return blk_ioctl_zeroout(bdev, mode, arg);
 573         case BLKGETDISKSEQ:
 574                 return put_u64(argp, bdev->bd_disk->diskseq);
 575         case BLKREPORTZONE:
 576                 return blkdev_report_zones_ioctl(bdev, cmd, arg);
 577         case BLKRESETZONE:
 578         case BLKOPENZONE:
 579         case BLKCLOSEZONE:
 580         case BLKFINISHZONE:
 581                 return blkdev_zone_mgmt_ioctl(bdev, mode, cmd, arg);
 582         case BLKGETZONESZ:
 583                 return put_uint(argp, bdev_zone_sectors(bdev));
 584         case BLKGETNRZONES:
 585                 return put_uint(argp, bdev_nr_zones(bdev));
 586         case BLKROGET:
 587                 return put_int(argp, bdev_read_only(bdev) != 0);
 588         case BLKSSZGET: /* get block device logical block size */
 589                 return put_int(argp, bdev_logical_block_size(bdev));
 590         case BLKPBSZGET: /* get block device physical block size */
 591                 return put_uint(argp, bdev_physical_block_size(bdev));
 592         case BLKIOMIN:
 593                 return put_uint(argp, bdev_io_min(bdev));
 594         case BLKIOOPT:
 595                 return put_uint(argp, bdev_io_opt(bdev));
 596         case BLKALIGNOFF:
 597                 return put_int(argp, bdev_alignment_offset(bdev));
 598         case BLKDISCARDZEROES:
 599                 return put_uint(argp, 0);
 600         case BLKSECTGET:
 601                 max_sectors = min_t(unsigned int, USHRT_MAX,
 602                                     queue_max_sectors(bdev_get_queue(bdev)));
 603                 return put_ushort(argp, max_sectors);
 604         case BLKROTATIONAL:
 605                 return put_ushort(argp, !bdev_nonrot(bdev));
 606         case BLKRASET:
 607         case BLKFRASET:
 608                 if(!capable(CAP_SYS_ADMIN))
 609                         return -EACCES;
 610                 bdev->bd_disk->bdi->ra_pages = (arg * 512) / PAGE_SIZE;
 611                 return 0;
 612         case BLKRRPART:
 613                 if (!capable(CAP_SYS_ADMIN))
 614                         return -EACCES;
 615                 if (bdev_is_partition(bdev))
 616                         return -EINVAL;
 617                 return disk_scan_partitions(bdev->bd_disk,
 618                                 mode | BLK_OPEN_STRICT_SCAN);
 619         case BLKTRACESTART:
 620         case BLKTRACESTOP:
 621         case BLKTRACETEARDOWN:
 622                 return blk_trace_ioctl(bdev, cmd, argp);
 623         case IOC_PR_REGISTER:
 624                 return blkdev_pr_register(bdev, mode, argp);
 625         case IOC_PR_RESERVE:
 626                 return blkdev_pr_reserve(bdev, mode, argp);
 627         case IOC_PR_RELEASE:
 628                 return blkdev_pr_release(bdev, mode, argp);
 629         case IOC_PR_PREEMPT:
 630                 return blkdev_pr_preempt(bdev, mode, argp, false);
 631         case IOC_PR_PREEMPT_ABORT:
 632                 return blkdev_pr_preempt(bdev, mode, argp, true);
 633         case IOC_PR_CLEAR:
 634                 return blkdev_pr_clear(bdev, mode, argp);
 635         default:
 636                 return -ENOIOCTLCMD;
 637         }
 638 }
 639
 640 /*
 641  * Always keep this in sync with compat_blkdev_ioctl()
 642  * to handle all incompatible commands in both functions.
 643  *
 644  * New commands must be compatible and go into blkdev_common_ioctl
 645  */
 646 long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 647 {
 648         struct block_device *bdev = I_BDEV(file->f_mapping->host);
 649         void __user *argp = (void __user *)arg;
 650         blk_mode_t mode = file_to_blk_mode(file);
 651         int ret;
 652
 653         switch (cmd) {
 654         /* These need separate implementations for the data structure */
 655         case HDIO_GETGEO:
 656                 return blkdev_getgeo(bdev, argp);
 657         case BLKPG:
 658                 return blkpg_ioctl(bdev, argp);
 659
 660         /* Compat mode returns 32-bit data instead of 'long' */
 661         case BLKRAGET:
 662         case BLKFRAGET:
 663                 if (!argp)
 664                         return -EINVAL;
 665                 return put_long(argp,
 666                         (bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
 667         case BLKGETSIZE:
 668                 if (bdev_nr_sectors(bdev) > ~0UL)
 669                         return -EFBIG;
 670                 return put_ulong(argp, bdev_nr_sectors(bdev));
 671
 672         /* The data is compatible, but the command number is different */
 673         case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
 674                 return put_int(argp, block_size(bdev));
 675         case BLKBSZSET:
 676                 return blkdev_bszset(file, mode, argp);
 677         case BLKGETSIZE64:
 678                 return put_u64(argp, bdev_nr_bytes(bdev));
 679
 680         /* Incompatible alignment on i386 */
 681         case BLKTRACESETUP:
 682                 return blk_trace_ioctl(bdev, cmd, argp);
 683         default:
 684                 break;
 685         }
 686
 687         ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
 688         if (ret != -ENOIOCTLCMD)
 689                 return ret;
 690
 691         if (!bdev->bd_disk->fops->ioctl)
 692                 return -ENOTTY;
 693         return bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
 694 }
 695
 696 #ifdef CONFIG_COMPAT
 697
 698 #define BLKBSZGET_32            _IOR(0x12, 112, int)
 699 #define BLKBSZSET_32            _IOW(0x12, 113, int)
 700 #define BLKGETSIZE64_32         _IOR(0x12, 114, int)
 701
 702 /* Most of the generic ioctls are handled in the normal fallback path.
 703    This assumes the blkdev's low level compat_ioctl always returns
 704    ENOIOCTLCMD for unknown ioctls. */
 705 long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 706 {
 707         int ret;
 708         void __user *argp = compat_ptr(arg);
 709         struct block_device *bdev = I_BDEV(file->f_mapping->host);
 710         struct gendisk *disk = bdev->bd_disk;
 711         blk_mode_t mode = file_to_blk_mode(file);
 712
 713         switch (cmd) {
 714         /* These need separate implementations for the data structure */
 715         case HDIO_GETGEO:
 716                 return compat_hdio_getgeo(bdev, argp);
 717         case BLKPG:
 718                 return compat_blkpg_ioctl(bdev, argp);
 719
 720         /* Compat mode returns 32-bit data instead of 'long' */
 721         case BLKRAGET:
 722         case BLKFRAGET:
 723                 if (!argp)
 724                         return -EINVAL;
 725                 return compat_put_long(argp,
 726                         (bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
 727         case BLKGETSIZE:
 728                 if (bdev_nr_sectors(bdev) > ~(compat_ulong_t)0)
 729                         return -EFBIG;
 730                 return compat_put_ulong(argp, bdev_nr_sectors(bdev));
 731
 732         /* The data is compatible, but the command number is different */
 733         case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */
 734                 return put_int(argp, bdev_logical_block_size(bdev));
 735         case BLKBSZSET_32:
 736                 return blkdev_bszset(file, mode, argp);
 737         case BLKGETSIZE64_32:
 738                 return put_u64(argp, bdev_nr_bytes(bdev));
 739
 740         /* Incompatible alignment on i386 */
 741         case BLKTRACESETUP32:
 742                 return blk_trace_ioctl(bdev, cmd, argp);
 743         default:
 744                 break;
 745         }
 746
 747         ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
 748         if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl)
 749                 ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg);
 750
 751         return ret;
 752 }
 753 #endif
 754
 755 struct blk_iou_cmd {
 756         int res;
 757         bool nowait;
 758 };
 759
 760 static void blk_cmd_complete(struct io_uring_cmd *cmd, unsigned int issue_flags)
 761 {
 762         struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
 763
 764         if (bic->res == -EAGAIN && bic->nowait)
 765                 io_uring_cmd_issue_blocking(cmd);
 766         else
 767                 io_uring_cmd_done(cmd, bic->res, 0, issue_flags);
 768 }
 769
 770 static void bio_cmd_bio_end_io(struct bio *bio)
 771 {
 772         struct io_uring_cmd *cmd = bio->bi_private;
 773         struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
 774
 775         if (unlikely(bio->bi_status) && !bic->res)
 776                 bic->res = blk_status_to_errno(bio->bi_status);
 777
 778         io_uring_cmd_do_in_task_lazy(cmd, blk_cmd_complete);
 779         bio_put(bio);
 780 }
 781
 782 static int blkdev_cmd_discard(struct io_uring_cmd *cmd,
 783                               struct block_device *bdev,
 784                               uint64_t start, uint64_t len, bool nowait)
 785 {
 786         struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
 787         gfp_t gfp = nowait ? GFP_NOWAIT : GFP_KERNEL;
 788         sector_t sector = start >> SECTOR_SHIFT;
 789         sector_t nr_sects = len >> SECTOR_SHIFT;
 790         struct bio *prev = NULL, *bio;
 791         int err;
 792
 793         if (!bdev_max_discard_sectors(bdev))
 794                 return -EOPNOTSUPP;
 795         if (!(file_to_blk_mode(cmd->file) & BLK_OPEN_WRITE))
 796                 return -EBADF;
 797         if (bdev_read_only(bdev))
 798                 return -EPERM;
 799         err = blk_validate_byte_range(bdev, start, len);
 800         if (err)
 801                 return err;
 802
 803         err = filemap_invalidate_pages(bdev->bd_mapping, start,
 804                                         start + len - 1, nowait);
 805         if (err)
 806                 return err;
 807
 808         while (true) {
 809                 bio = blk_alloc_discard_bio(bdev, &sector, &nr_sects, gfp);
 810                 if (!bio)
 811                         break;
 812                 if (nowait) {
 813                         /*
 814                          * Don't allow multi-bio non-blocking submissions as
 815                          * subsequent bios may fail but we won't get a direct
 816                          * indication of that. Normally, the caller should
 817                          * retry from a blocking context.
 818                          */
 819                         if (unlikely(nr_sects)) {
 820                                 bio_put(bio);
 821                                 return -EAGAIN;
 822                         }
 823                         bio->bi_opf |= REQ_NOWAIT;
 824                 }
 825
 826                 prev = bio_chain_and_submit(prev, bio);
 827         }
 828         if (unlikely(!prev))
 829                 return -EAGAIN;
 830         if (unlikely(nr_sects))
 831                 bic->res = -EAGAIN;
 832
 833         prev->bi_private = cmd;
 834         prev->bi_end_io = bio_cmd_bio_end_io;
 835         submit_bio(prev);
 836         return -EIOCBQUEUED;
 837 }
 838
 839 int blkdev_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
 840 {
 841         struct block_device *bdev = I_BDEV(cmd->file->f_mapping->host);
 842         struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
 843         const struct io_uring_sqe *sqe = cmd->sqe;
 844         u32 cmd_op = cmd->cmd_op;
 845         uint64_t start, len;
 846
 847         if (unlikely(sqe->ioprio || sqe->__pad1 || sqe->len ||
 848                      sqe->rw_flags || sqe->file_index))
 849                 return -EINVAL;
 850
 851         bic->res = 0;
 852         bic->nowait = issue_flags & IO_URING_F_NONBLOCK;
 853
 854         start = READ_ONCE(sqe->addr);
 855         len = READ_ONCE(sqe->addr3);
 856
 857         switch (cmd_op) {
 858         case BLOCK_URING_CMD_DISCARD:
 859                 return blkdev_cmd_discard(cmd, bdev, start, len, bic->nowait);
 860         }
 861         return -EINVAL;
 862 }