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
16static int blkpg_do_ioctl(struct block_device *bdev,
17 struct blkpg_partition __user *upart, int op)
18{
19 struct gendisk *disk = bdev->bd_disk;
20 struct blkpg_partition p;
21 sector_t start, length, capacity, end;
22
23 if (!capable(CAP_SYS_ADMIN))
24 return -EACCES;
25 if (copy_from_user(to: &p, from: upart, n: sizeof(struct blkpg_partition)))
26 return -EFAULT;
27 if (bdev_is_partition(bdev))
28 return -EINVAL;
29
30 if (p.pno <= 0)
31 return -EINVAL;
32
33 if (op == BLKPG_DEL_PARTITION)
34 return bdev_del_partition(disk, partno: p.pno);
35
36 if (p.start < 0 || p.length <= 0 || p.start + p.length < 0)
37 return -EINVAL;
38 /* Check that the partition is aligned to the block size */
39 if (!IS_ALIGNED(p.start | p.length, bdev_logical_block_size(bdev)))
40 return -EINVAL;
41
42 start = p.start >> SECTOR_SHIFT;
43 length = p.length >> SECTOR_SHIFT;
44 capacity = get_capacity(disk);
45
46 if (check_add_overflow(start, length, &end))
47 return -EINVAL;
48
49 if (start >= capacity || end > capacity)
50 return -EINVAL;
51
52 switch (op) {
53 case BLKPG_ADD_PARTITION:
54 return bdev_add_partition(disk, partno: p.pno, start, length);
55 case BLKPG_RESIZE_PARTITION:
56 return bdev_resize_partition(disk, partno: p.pno, start, length);
57 default:
58 return -EINVAL;
59 }
60}
61
62static int blkpg_ioctl(struct block_device *bdev,
63 struct blkpg_ioctl_arg __user *arg)
64{
65 struct blkpg_partition __user *udata;
66 int op;
67
68 if (get_user(op, &arg->op) || get_user(udata, &arg->data))
69 return -EFAULT;
70
71 return blkpg_do_ioctl(bdev, upart: udata, op);
72}
73
74#ifdef CONFIG_COMPAT
75struct compat_blkpg_ioctl_arg {
76 compat_int_t op;
77 compat_int_t flags;
78 compat_int_t datalen;
79 compat_caddr_t data;
80};
81
82static int compat_blkpg_ioctl(struct block_device *bdev,
83 struct compat_blkpg_ioctl_arg __user *arg)
84{
85 compat_caddr_t udata;
86 int op;
87
88 if (get_user(op, &arg->op) || get_user(udata, &arg->data))
89 return -EFAULT;
90
91 return blkpg_do_ioctl(bdev, upart: compat_ptr(uptr: udata), op);
92}
93#endif
94
95static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
96 unsigned long arg)
97{
98 uint64_t range[2];
99 uint64_t start, len, end;
100 struct inode *inode = bdev->bd_inode;
101 int err;
102
103 if (!(mode & BLK_OPEN_WRITE))
104 return -EBADF;
105
106 if (!bdev_max_discard_sectors(bdev))
107 return -EOPNOTSUPP;
108
109 if (copy_from_user(to: range, from: (void __user *)arg, n: sizeof(range)))
110 return -EFAULT;
111
112 start = range[0];
113 len = range[1];
114
115 if (start & 511)
116 return -EINVAL;
117 if (len & 511)
118 return -EINVAL;
119
120 if (check_add_overflow(start, len, &end) ||
121 end > bdev_nr_bytes(bdev))
122 return -EINVAL;
123
124 filemap_invalidate_lock(mapping: inode->i_mapping);
125 err = truncate_bdev_range(bdev, mode, lstart: start, lend: start + len - 1);
126 if (err)
127 goto fail;
128 err = blkdev_issue_discard(bdev, sector: start >> 9, nr_sects: len >> 9, GFP_KERNEL);
129fail:
130 filemap_invalidate_unlock(mapping: inode->i_mapping);
131 return err;
132}
133
134static int blk_ioctl_secure_erase(struct block_device *bdev, blk_mode_t mode,
135 void __user *argp)
136{
137 uint64_t start, len;
138 uint64_t range[2];
139 int err;
140
141 if (!(mode & BLK_OPEN_WRITE))
142 return -EBADF;
143 if (!bdev_max_secure_erase_sectors(bdev))
144 return -EOPNOTSUPP;
145 if (copy_from_user(to: range, from: argp, n: sizeof(range)))
146 return -EFAULT;
147
148 start = range[0];
149 len = range[1];
150 if ((start & 511) || (len & 511))
151 return -EINVAL;
152 if (start + len > bdev_nr_bytes(bdev))
153 return -EINVAL;
154
155 filemap_invalidate_lock(mapping: bdev->bd_inode->i_mapping);
156 err = truncate_bdev_range(bdev, mode, lstart: start, lend: start + len - 1);
157 if (!err)
158 err = blkdev_issue_secure_erase(bdev, sector: start >> 9, nr_sects: len >> 9,
159 GFP_KERNEL);
160 filemap_invalidate_unlock(mapping: bdev->bd_inode->i_mapping);
161 return err;
162}
163
164
165static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
166 unsigned long arg)
167{
168 uint64_t range[2];
169 uint64_t start, end, len;
170 struct inode *inode = bdev->bd_inode;
171 int err;
172
173 if (!(mode & BLK_OPEN_WRITE))
174 return -EBADF;
175
176 if (copy_from_user(to: range, from: (void __user *)arg, n: sizeof(range)))
177 return -EFAULT;
178
179 start = range[0];
180 len = range[1];
181 end = start + len - 1;
182
183 if (start & 511)
184 return -EINVAL;
185 if (len & 511)
186 return -EINVAL;
187 if (end >= (uint64_t)bdev_nr_bytes(bdev))
188 return -EINVAL;
189 if (end < start)
190 return -EINVAL;
191
192 /* Invalidate the page cache, including dirty pages */
193 filemap_invalidate_lock(mapping: inode->i_mapping);
194 err = truncate_bdev_range(bdev, mode, lstart: start, lend: end);
195 if (err)
196 goto fail;
197
198 err = blkdev_issue_zeroout(bdev, sector: start >> 9, nr_sects: len >> 9, GFP_KERNEL,
199 BLKDEV_ZERO_NOUNMAP);
200
201fail:
202 filemap_invalidate_unlock(mapping: inode->i_mapping);
203 return err;
204}
205
206static int put_ushort(unsigned short __user *argp, unsigned short val)
207{
208 return put_user(val, argp);
209}
210
211static int put_int(int __user *argp, int val)
212{
213 return put_user(val, argp);
214}
215
216static int put_uint(unsigned int __user *argp, unsigned int val)
217{
218 return put_user(val, argp);
219}
220
221static int put_long(long __user *argp, long val)
222{
223 return put_user(val, argp);
224}
225
226static int put_ulong(unsigned long __user *argp, unsigned long val)
227{
228 return put_user(val, argp);
229}
230
231static int put_u64(u64 __user *argp, u64 val)
232{
233 return put_user(val, argp);
234}
235
236#ifdef CONFIG_COMPAT
237static int compat_put_long(compat_long_t __user *argp, long val)
238{
239 return put_user(val, argp);
240}
241
242static int compat_put_ulong(compat_ulong_t __user *argp, compat_ulong_t val)
243{
244 return put_user(val, argp);
245}
246#endif
247
248#ifdef CONFIG_COMPAT
249/*
250 * This is the equivalent of compat_ptr_ioctl(), to be used by block
251 * drivers that implement only commands that are completely compatible
252 * between 32-bit and 64-bit user space
253 */
254int blkdev_compat_ptr_ioctl(struct block_device *bdev, blk_mode_t mode,
255 unsigned cmd, unsigned long arg)
256{
257 struct gendisk *disk = bdev->bd_disk;
258
259 if (disk->fops->ioctl)
260 return disk->fops->ioctl(bdev, mode, cmd,
261 (unsigned long)compat_ptr(uptr: arg));
262
263 return -ENOIOCTLCMD;
264}
265EXPORT_SYMBOL(blkdev_compat_ptr_ioctl);
266#endif
267
268static bool blkdev_pr_allowed(struct block_device *bdev, blk_mode_t mode)
269{
270 /* no sense to make reservations for partitions */
271 if (bdev_is_partition(bdev))
272 return false;
273
274 if (capable(CAP_SYS_ADMIN))
275 return true;
276 /*
277 * Only allow unprivileged reservations if the file descriptor is open
278 * for writing.
279 */
280 return mode & BLK_OPEN_WRITE;
281}
282
283static int blkdev_pr_register(struct block_device *bdev, blk_mode_t mode,
284 struct pr_registration __user *arg)
285{
286 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
287 struct pr_registration reg;
288
289 if (!blkdev_pr_allowed(bdev, mode))
290 return -EPERM;
291 if (!ops || !ops->pr_register)
292 return -EOPNOTSUPP;
293 if (copy_from_user(to: &reg, from: arg, n: sizeof(reg)))
294 return -EFAULT;
295
296 if (reg.flags & ~PR_FL_IGNORE_KEY)
297 return -EOPNOTSUPP;
298 return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);
299}
300
301static int blkdev_pr_reserve(struct block_device *bdev, blk_mode_t mode,
302 struct pr_reservation __user *arg)
303{
304 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
305 struct pr_reservation rsv;
306
307 if (!blkdev_pr_allowed(bdev, mode))
308 return -EPERM;
309 if (!ops || !ops->pr_reserve)
310 return -EOPNOTSUPP;
311 if (copy_from_user(to: &rsv, from: arg, n: sizeof(rsv)))
312 return -EFAULT;
313
314 if (rsv.flags & ~PR_FL_IGNORE_KEY)
315 return -EOPNOTSUPP;
316 return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);
317}
318
319static int blkdev_pr_release(struct block_device *bdev, blk_mode_t mode,
320 struct pr_reservation __user *arg)
321{
322 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
323 struct pr_reservation rsv;
324
325 if (!blkdev_pr_allowed(bdev, mode))
326 return -EPERM;
327 if (!ops || !ops->pr_release)
328 return -EOPNOTSUPP;
329 if (copy_from_user(to: &rsv, from: arg, n: sizeof(rsv)))
330 return -EFAULT;
331
332 if (rsv.flags)
333 return -EOPNOTSUPP;
334 return ops->pr_release(bdev, rsv.key, rsv.type);
335}
336
337static int blkdev_pr_preempt(struct block_device *bdev, blk_mode_t mode,
338 struct pr_preempt __user *arg, bool abort)
339{
340 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
341 struct pr_preempt p;
342
343 if (!blkdev_pr_allowed(bdev, mode))
344 return -EPERM;
345 if (!ops || !ops->pr_preempt)
346 return -EOPNOTSUPP;
347 if (copy_from_user(to: &p, from: arg, n: sizeof(p)))
348 return -EFAULT;
349
350 if (p.flags)
351 return -EOPNOTSUPP;
352 return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);
353}
354
355static int blkdev_pr_clear(struct block_device *bdev, blk_mode_t mode,
356 struct pr_clear __user *arg)
357{
358 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
359 struct pr_clear c;
360
361 if (!blkdev_pr_allowed(bdev, mode))
362 return -EPERM;
363 if (!ops || !ops->pr_clear)
364 return -EOPNOTSUPP;
365 if (copy_from_user(to: &c, from: arg, n: sizeof(c)))
366 return -EFAULT;
367
368 if (c.flags)
369 return -EOPNOTSUPP;
370 return ops->pr_clear(bdev, c.key);
371}
372
373static int blkdev_flushbuf(struct block_device *bdev, unsigned cmd,
374 unsigned long arg)
375{
376 if (!capable(CAP_SYS_ADMIN))
377 return -EACCES;
378
379 mutex_lock(&bdev->bd_holder_lock);
380 if (bdev->bd_holder_ops && bdev->bd_holder_ops->sync)
381 bdev->bd_holder_ops->sync(bdev);
382 else {
383 mutex_unlock(lock: &bdev->bd_holder_lock);
384 sync_blockdev(bdev);
385 }
386
387 invalidate_bdev(bdev);
388 return 0;
389}
390
391static int blkdev_roset(struct block_device *bdev, unsigned cmd,
392 unsigned long arg)
393{
394 int ret, n;
395
396 if (!capable(CAP_SYS_ADMIN))
397 return -EACCES;
398
399 if (get_user(n, (int __user *)arg))
400 return -EFAULT;
401 if (bdev->bd_disk->fops->set_read_only) {
402 ret = bdev->bd_disk->fops->set_read_only(bdev, n);
403 if (ret)
404 return ret;
405 }
406 bdev->bd_read_only = n;
407 return 0;
408}
409
410static int blkdev_getgeo(struct block_device *bdev,
411 struct hd_geometry __user *argp)
412{
413 struct gendisk *disk = bdev->bd_disk;
414 struct hd_geometry geo;
415 int ret;
416
417 if (!argp)
418 return -EINVAL;
419 if (!disk->fops->getgeo)
420 return -ENOTTY;
421
422 /*
423 * We need to set the startsect first, the driver may
424 * want to override it.
425 */
426 memset(&geo, 0, sizeof(geo));
427 geo.start = get_start_sect(bdev);
428 ret = disk->fops->getgeo(bdev, &geo);
429 if (ret)
430 return ret;
431 if (copy_to_user(to: argp, from: &geo, n: sizeof(geo)))
432 return -EFAULT;
433 return 0;
434}
435
436#ifdef CONFIG_COMPAT
437struct compat_hd_geometry {
438 unsigned char heads;
439 unsigned char sectors;
440 unsigned short cylinders;
441 u32 start;
442};
443
444static int compat_hdio_getgeo(struct block_device *bdev,
445 struct compat_hd_geometry __user *ugeo)
446{
447 struct gendisk *disk = bdev->bd_disk;
448 struct hd_geometry geo;
449 int ret;
450
451 if (!ugeo)
452 return -EINVAL;
453 if (!disk->fops->getgeo)
454 return -ENOTTY;
455
456 memset(&geo, 0, sizeof(geo));
457 /*
458 * We need to set the startsect first, the driver may
459 * want to override it.
460 */
461 geo.start = get_start_sect(bdev);
462 ret = disk->fops->getgeo(bdev, &geo);
463 if (ret)
464 return ret;
465
466 ret = copy_to_user(to: ugeo, from: &geo, n: 4);
467 ret |= put_user(geo.start, &ugeo->start);
468 if (ret)
469 ret = -EFAULT;
470
471 return ret;
472}
473#endif
474
475/* set the logical block size */
476static int blkdev_bszset(struct block_device *bdev, blk_mode_t mode,
477 int __user *argp)
478{
479 int ret, n;
480 struct file *file;
481
482 if (!capable(CAP_SYS_ADMIN))
483 return -EACCES;
484 if (!argp)
485 return -EINVAL;
486 if (get_user(n, argp))
487 return -EFAULT;
488
489 if (mode & BLK_OPEN_EXCL)
490 return set_blocksize(bdev, size: n);
491
492 file = bdev_file_open_by_dev(dev: bdev->bd_dev, mode, holder: &bdev, NULL);
493 if (IS_ERR(ptr: file))
494 return -EBUSY;
495 ret = set_blocksize(bdev, size: n);
496 fput(file);
497 return ret;
498}
499
500/*
501 * Common commands that are handled the same way on native and compat
502 * user space. Note the separate arg/argp parameters that are needed
503 * to deal with the compat_ptr() conversion.
504 */
505static int blkdev_common_ioctl(struct block_device *bdev, blk_mode_t mode,
506 unsigned int cmd, unsigned long arg,
507 void __user *argp)
508{
509 unsigned int max_sectors;
510
511 switch (cmd) {
512 case BLKFLSBUF:
513 return blkdev_flushbuf(bdev, cmd, arg);
514 case BLKROSET:
515 return blkdev_roset(bdev, cmd, arg);
516 case BLKDISCARD:
517 return blk_ioctl_discard(bdev, mode, arg);
518 case BLKSECDISCARD:
519 return blk_ioctl_secure_erase(bdev, mode, argp);
520 case BLKZEROOUT:
521 return blk_ioctl_zeroout(bdev, mode, arg);
522 case BLKGETDISKSEQ:
523 return put_u64(argp, val: bdev->bd_disk->diskseq);
524 case BLKREPORTZONE:
525 return blkdev_report_zones_ioctl(bdev, cmd, arg);
526 case BLKRESETZONE:
527 case BLKOPENZONE:
528 case BLKCLOSEZONE:
529 case BLKFINISHZONE:
530 return blkdev_zone_mgmt_ioctl(bdev, mode, cmd, arg);
531 case BLKGETZONESZ:
532 return put_uint(argp, val: bdev_zone_sectors(bdev));
533 case BLKGETNRZONES:
534 return put_uint(argp, val: bdev_nr_zones(bdev));
535 case BLKROGET:
536 return put_int(argp, val: bdev_read_only(bdev) != 0);
537 case BLKSSZGET: /* get block device logical block size */
538 return put_int(argp, val: bdev_logical_block_size(bdev));
539 case BLKPBSZGET: /* get block device physical block size */
540 return put_uint(argp, val: bdev_physical_block_size(bdev));
541 case BLKIOMIN:
542 return put_uint(argp, val: bdev_io_min(bdev));
543 case BLKIOOPT:
544 return put_uint(argp, val: bdev_io_opt(bdev));
545 case BLKALIGNOFF:
546 return put_int(argp, val: bdev_alignment_offset(bdev));
547 case BLKDISCARDZEROES:
548 return put_uint(argp, val: 0);
549 case BLKSECTGET:
550 max_sectors = min_t(unsigned int, USHRT_MAX,
551 queue_max_sectors(bdev_get_queue(bdev)));
552 return put_ushort(argp, val: max_sectors);
553 case BLKROTATIONAL:
554 return put_ushort(argp, val: !bdev_nonrot(bdev));
555 case BLKRASET:
556 case BLKFRASET:
557 if(!capable(CAP_SYS_ADMIN))
558 return -EACCES;
559 bdev->bd_disk->bdi->ra_pages = (arg * 512) / PAGE_SIZE;
560 return 0;
561 case BLKRRPART:
562 if (!capable(CAP_SYS_ADMIN))
563 return -EACCES;
564 if (bdev_is_partition(bdev))
565 return -EINVAL;
566 return disk_scan_partitions(disk: bdev->bd_disk,
567 mode: mode | BLK_OPEN_STRICT_SCAN);
568 case BLKTRACESTART:
569 case BLKTRACESTOP:
570 case BLKTRACETEARDOWN:
571 return blk_trace_ioctl(bdev, cmd, argp);
572 case IOC_PR_REGISTER:
573 return blkdev_pr_register(bdev, mode, arg: argp);
574 case IOC_PR_RESERVE:
575 return blkdev_pr_reserve(bdev, mode, arg: argp);
576 case IOC_PR_RELEASE:
577 return blkdev_pr_release(bdev, mode, arg: argp);
578 case IOC_PR_PREEMPT:
579 return blkdev_pr_preempt(bdev, mode, arg: argp, abort: false);
580 case IOC_PR_PREEMPT_ABORT:
581 return blkdev_pr_preempt(bdev, mode, arg: argp, abort: true);
582 case IOC_PR_CLEAR:
583 return blkdev_pr_clear(bdev, mode, arg: argp);
584 default:
585 return -ENOIOCTLCMD;
586 }
587}
588
589/*
590 * Always keep this in sync with compat_blkdev_ioctl()
591 * to handle all incompatible commands in both functions.
592 *
593 * New commands must be compatible and go into blkdev_common_ioctl
594 */
595long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
596{
597 struct block_device *bdev = I_BDEV(inode: file->f_mapping->host);
598 void __user *argp = (void __user *)arg;
599 blk_mode_t mode = file_to_blk_mode(file);
600 int ret;
601
602 switch (cmd) {
603 /* These need separate implementations for the data structure */
604 case HDIO_GETGEO:
605 return blkdev_getgeo(bdev, argp);
606 case BLKPG:
607 return blkpg_ioctl(bdev, arg: argp);
608
609 /* Compat mode returns 32-bit data instead of 'long' */
610 case BLKRAGET:
611 case BLKFRAGET:
612 if (!argp)
613 return -EINVAL;
614 return put_long(argp,
615 val: (bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
616 case BLKGETSIZE:
617 if (bdev_nr_sectors(bdev) > ~0UL)
618 return -EFBIG;
619 return put_ulong(argp, val: bdev_nr_sectors(bdev));
620
621 /* The data is compatible, but the command number is different */
622 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
623 return put_int(argp, val: block_size(bdev));
624 case BLKBSZSET:
625 return blkdev_bszset(bdev, mode, argp);
626 case BLKGETSIZE64:
627 return put_u64(argp, val: bdev_nr_bytes(bdev));
628
629 /* Incompatible alignment on i386 */
630 case BLKTRACESETUP:
631 return blk_trace_ioctl(bdev, cmd, argp);
632 default:
633 break;
634 }
635
636 ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
637 if (ret != -ENOIOCTLCMD)
638 return ret;
639
640 if (!bdev->bd_disk->fops->ioctl)
641 return -ENOTTY;
642 return bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
643}
644
645#ifdef CONFIG_COMPAT
646
647#define BLKBSZGET_32 _IOR(0x12, 112, int)
648#define BLKBSZSET_32 _IOW(0x12, 113, int)
649#define BLKGETSIZE64_32 _IOR(0x12, 114, int)
650
651/* Most of the generic ioctls are handled in the normal fallback path.
652 This assumes the blkdev's low level compat_ioctl always returns
653 ENOIOCTLCMD for unknown ioctls. */
654long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
655{
656 int ret;
657 void __user *argp = compat_ptr(uptr: arg);
658 struct block_device *bdev = I_BDEV(inode: file->f_mapping->host);
659 struct gendisk *disk = bdev->bd_disk;
660 blk_mode_t mode = file_to_blk_mode(file);
661
662 switch (cmd) {
663 /* These need separate implementations for the data structure */
664 case HDIO_GETGEO:
665 return compat_hdio_getgeo(bdev, ugeo: argp);
666 case BLKPG:
667 return compat_blkpg_ioctl(bdev, arg: argp);
668
669 /* Compat mode returns 32-bit data instead of 'long' */
670 case BLKRAGET:
671 case BLKFRAGET:
672 if (!argp)
673 return -EINVAL;
674 return compat_put_long(argp,
675 val: (bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
676 case BLKGETSIZE:
677 if (bdev_nr_sectors(bdev) > ~(compat_ulong_t)0)
678 return -EFBIG;
679 return compat_put_ulong(argp, val: bdev_nr_sectors(bdev));
680
681 /* The data is compatible, but the command number is different */
682 case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */
683 return put_int(argp, val: bdev_logical_block_size(bdev));
684 case BLKBSZSET_32:
685 return blkdev_bszset(bdev, mode, argp);
686 case BLKGETSIZE64_32:
687 return put_u64(argp, val: bdev_nr_bytes(bdev));
688
689 /* Incompatible alignment on i386 */
690 case BLKTRACESETUP32:
691 return blk_trace_ioctl(bdev, cmd, argp);
692 default:
693 break;
694 }
695
696 ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
697 if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl)
698 ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg);
699
700 return ret;
701}
702#endif
703

source code of linux/block/ioctl.c