xref: /linux/block/ioctl.c (revision b61104e7a6349bd2c2b3e2fb3260d87f15eda8f4)
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 <linux/blk-integrity.h>
17 #include <uapi/linux/blkdev.h>
18 #include "blk.h"
19 #include "blk-crypto-internal.h"
20 
21 static int blkpg_do_ioctl(struct block_device *bdev,
22 			  struct blkpg_partition __user *upart, int op)
23 {
24 	struct gendisk *disk = bdev->bd_disk;
25 	struct blkpg_partition p;
26 	sector_t start, length, capacity, end;
27 
28 	if (!capable(CAP_SYS_ADMIN))
29 		return -EACCES;
30 	if (copy_from_user(&p, upart, sizeof(struct blkpg_partition)))
31 		return -EFAULT;
32 	if (bdev_is_partition(bdev))
33 		return -EINVAL;
34 
35 	if (p.pno <= 0)
36 		return -EINVAL;
37 
38 	if (op == BLKPG_DEL_PARTITION)
39 		return bdev_del_partition(disk, p.pno);
40 
41 	if (p.start < 0 || p.length <= 0 || LLONG_MAX - p.length < p.start)
42 		return -EINVAL;
43 	/* Check that the partition is aligned to the block size */
44 	if (!IS_ALIGNED(p.start | p.length, bdev_logical_block_size(bdev)))
45 		return -EINVAL;
46 
47 	start = p.start >> SECTOR_SHIFT;
48 	length = p.length >> SECTOR_SHIFT;
49 	capacity = get_capacity(disk);
50 
51 	if (check_add_overflow(start, length, &end))
52 		return -EINVAL;
53 
54 	if (start >= capacity || end > capacity)
55 		return -EINVAL;
56 
57 	switch (op) {
58 	case BLKPG_ADD_PARTITION:
59 		return bdev_add_partition(disk, p.pno, start, length);
60 	case BLKPG_RESIZE_PARTITION:
61 		return bdev_resize_partition(disk, p.pno, start, length);
62 	default:
63 		return -EINVAL;
64 	}
65 }
66 
67 static int blkpg_ioctl(struct block_device *bdev,
68 		       struct blkpg_ioctl_arg __user *arg)
69 {
70 	struct blkpg_partition __user *udata;
71 	int op;
72 
73 	if (get_user(op, &arg->op) || get_user(udata, &arg->data))
74 		return -EFAULT;
75 
76 	return blkpg_do_ioctl(bdev, udata, op);
77 }
78 
79 #ifdef CONFIG_COMPAT
80 struct compat_blkpg_ioctl_arg {
81 	compat_int_t op;
82 	compat_int_t flags;
83 	compat_int_t datalen;
84 	compat_caddr_t data;
85 };
86 
87 static int compat_blkpg_ioctl(struct block_device *bdev,
88 			      struct compat_blkpg_ioctl_arg __user *arg)
89 {
90 	compat_caddr_t udata;
91 	int op;
92 
93 	if (get_user(op, &arg->op) || get_user(udata, &arg->data))
94 		return -EFAULT;
95 
96 	return blkpg_do_ioctl(bdev, compat_ptr(udata), op);
97 }
98 #endif
99 
100 /*
101  * Check that [start, start + len) is a valid range from the block device's
102  * perspective, including verifying that it can be correctly translated into
103  * logical block addresses.
104  */
105 static int blk_validate_byte_range(struct block_device *bdev,
106 				   uint64_t start, uint64_t len)
107 {
108 	unsigned int bs_mask = bdev_logical_block_size(bdev) - 1;
109 	uint64_t end;
110 
111 	if ((start | len) & bs_mask)
112 		return -EINVAL;
113 	if (!len)
114 		return -EINVAL;
115 	if (check_add_overflow(start, len, &end) || end > bdev_nr_bytes(bdev))
116 		return -EINVAL;
117 
118 	return 0;
119 }
120 
121 static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
122 		unsigned long arg)
123 {
124 	uint64_t range[2], start, len;
125 	struct bio *prev = NULL, *bio;
126 	sector_t sector, nr_sects;
127 	struct blk_plug plug;
128 	int err;
129 
130 	if (copy_from_user(range, (void __user *)arg, sizeof(range)))
131 		return -EFAULT;
132 	start = range[0];
133 	len = range[1];
134 
135 	if (!bdev_max_discard_sectors(bdev))
136 		return -EOPNOTSUPP;
137 
138 	if (!(mode & BLK_OPEN_WRITE))
139 		return -EBADF;
140 	if (bdev_read_only(bdev))
141 		return -EPERM;
142 	err = blk_validate_byte_range(bdev, start, len);
143 	if (err)
144 		return err;
145 
146 	inode_lock(bdev->bd_mapping->host);
147 	filemap_invalidate_lock(bdev->bd_mapping);
148 	err = truncate_bdev_range(bdev, mode, start, start + len - 1);
149 	if (err)
150 		goto fail;
151 
152 	sector = start >> SECTOR_SHIFT;
153 	nr_sects = len >> SECTOR_SHIFT;
154 
155 	blk_start_plug(&plug);
156 	while (1) {
157 		if (fatal_signal_pending(current)) {
158 			if (prev)
159 				bio_await_chain(prev);
160 			err = -EINTR;
161 			goto out_unplug;
162 		}
163 		bio = blk_alloc_discard_bio(bdev, &sector, &nr_sects,
164 				GFP_KERNEL);
165 		if (!bio)
166 			break;
167 		prev = bio_chain_and_submit(prev, bio);
168 	}
169 	if (prev) {
170 		err = submit_bio_wait(prev);
171 		if (err == -EOPNOTSUPP)
172 			err = 0;
173 		bio_put(prev);
174 	}
175 out_unplug:
176 	blk_finish_plug(&plug);
177 fail:
178 	filemap_invalidate_unlock(bdev->bd_mapping);
179 	inode_unlock(bdev->bd_mapping->host);
180 	return err;
181 }
182 
183 static int blk_ioctl_secure_erase(struct block_device *bdev, blk_mode_t mode,
184 		void __user *argp)
185 {
186 	uint64_t start, len, end;
187 	uint64_t range[2];
188 	int err;
189 
190 	if (!(mode & BLK_OPEN_WRITE))
191 		return -EBADF;
192 	if (!bdev_max_secure_erase_sectors(bdev))
193 		return -EOPNOTSUPP;
194 	if (copy_from_user(range, argp, sizeof(range)))
195 		return -EFAULT;
196 
197 	start = range[0];
198 	len = range[1];
199 	if ((start & 511) || (len & 511))
200 		return -EINVAL;
201 	if (check_add_overflow(start, len, &end) ||
202 	    end > bdev_nr_bytes(bdev))
203 		return -EINVAL;
204 
205 	inode_lock(bdev->bd_mapping->host);
206 	filemap_invalidate_lock(bdev->bd_mapping);
207 	err = truncate_bdev_range(bdev, mode, start, end - 1);
208 	if (!err)
209 		err = blkdev_issue_secure_erase(bdev, start >> 9, len >> 9,
210 						GFP_KERNEL);
211 	filemap_invalidate_unlock(bdev->bd_mapping);
212 	inode_unlock(bdev->bd_mapping->host);
213 	return err;
214 }
215 
216 
217 static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
218 		unsigned long arg)
219 {
220 	uint64_t range[2];
221 	uint64_t start, end, len;
222 	int err;
223 
224 	if (!(mode & BLK_OPEN_WRITE))
225 		return -EBADF;
226 
227 	if (copy_from_user(range, (void __user *)arg, sizeof(range)))
228 		return -EFAULT;
229 
230 	start = range[0];
231 	len = range[1];
232 	end = start + len - 1;
233 
234 	if (start & 511)
235 		return -EINVAL;
236 	if (len & 511)
237 		return -EINVAL;
238 	if (end >= (uint64_t)bdev_nr_bytes(bdev))
239 		return -EINVAL;
240 	if (end < start)
241 		return -EINVAL;
242 
243 	/* Invalidate the page cache, including dirty pages */
244 	inode_lock(bdev->bd_mapping->host);
245 	filemap_invalidate_lock(bdev->bd_mapping);
246 	err = truncate_bdev_range(bdev, mode, start, end);
247 	if (err)
248 		goto fail;
249 
250 	err = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,
251 				   BLKDEV_ZERO_NOUNMAP | BLKDEV_ZERO_KILLABLE);
252 
253 fail:
254 	filemap_invalidate_unlock(bdev->bd_mapping);
255 	inode_unlock(bdev->bd_mapping->host);
256 	return err;
257 }
258 
259 static int put_ushort(unsigned short __user *argp, unsigned short val)
260 {
261 	return put_user(val, argp);
262 }
263 
264 static int put_int(int __user *argp, int val)
265 {
266 	return put_user(val, argp);
267 }
268 
269 static int put_uint(unsigned int __user *argp, unsigned int val)
270 {
271 	return put_user(val, argp);
272 }
273 
274 static int put_long(long __user *argp, long val)
275 {
276 	return put_user(val, argp);
277 }
278 
279 static int put_ulong(unsigned long __user *argp, unsigned long val)
280 {
281 	return put_user(val, argp);
282 }
283 
284 static int put_u64(u64 __user *argp, u64 val)
285 {
286 	return put_user(val, argp);
287 }
288 
289 #ifdef CONFIG_COMPAT
290 static int compat_put_long(compat_long_t __user *argp, long val)
291 {
292 	return put_user(val, argp);
293 }
294 
295 static int compat_put_ulong(compat_ulong_t __user *argp, compat_ulong_t val)
296 {
297 	return put_user(val, argp);
298 }
299 #endif
300 
301 #ifdef CONFIG_COMPAT
302 /*
303  * This is the equivalent of compat_ptr_ioctl(), to be used by block
304  * drivers that implement only commands that are completely compatible
305  * between 32-bit and 64-bit user space
306  */
307 int blkdev_compat_ptr_ioctl(struct block_device *bdev, blk_mode_t mode,
308 			unsigned cmd, unsigned long arg)
309 {
310 	struct gendisk *disk = bdev->bd_disk;
311 
312 	if (disk->fops->ioctl)
313 		return disk->fops->ioctl(bdev, mode, cmd,
314 					 (unsigned long)compat_ptr(arg));
315 
316 	return -ENOIOCTLCMD;
317 }
318 EXPORT_SYMBOL(blkdev_compat_ptr_ioctl);
319 #endif
320 
321 static bool blkdev_pr_allowed(struct block_device *bdev, blk_mode_t mode)
322 {
323 	/* no sense to make reservations for partitions */
324 	if (bdev_is_partition(bdev))
325 		return false;
326 
327 	if (capable(CAP_SYS_ADMIN))
328 		return true;
329 	/*
330 	 * Only allow unprivileged reservations if the file descriptor is open
331 	 * for writing.
332 	 */
333 	return mode & BLK_OPEN_WRITE;
334 }
335 
336 static int blkdev_pr_register(struct block_device *bdev, blk_mode_t mode,
337 		struct pr_registration __user *arg)
338 {
339 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
340 	struct pr_registration reg;
341 
342 	if (!blkdev_pr_allowed(bdev, mode))
343 		return -EPERM;
344 	if (!ops || !ops->pr_register)
345 		return -EOPNOTSUPP;
346 	if (copy_from_user(&reg, arg, sizeof(reg)))
347 		return -EFAULT;
348 
349 	if (reg.flags & ~PR_FL_IGNORE_KEY)
350 		return -EOPNOTSUPP;
351 	return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);
352 }
353 
354 static int blkdev_pr_reserve(struct block_device *bdev, blk_mode_t mode,
355 		struct pr_reservation __user *arg)
356 {
357 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
358 	struct pr_reservation rsv;
359 
360 	if (!blkdev_pr_allowed(bdev, mode))
361 		return -EPERM;
362 	if (!ops || !ops->pr_reserve)
363 		return -EOPNOTSUPP;
364 	if (copy_from_user(&rsv, arg, sizeof(rsv)))
365 		return -EFAULT;
366 
367 	if (rsv.flags & ~PR_FL_IGNORE_KEY)
368 		return -EOPNOTSUPP;
369 	return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);
370 }
371 
372 static int blkdev_pr_release(struct block_device *bdev, blk_mode_t mode,
373 		struct pr_reservation __user *arg)
374 {
375 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
376 	struct pr_reservation rsv;
377 
378 	if (!blkdev_pr_allowed(bdev, mode))
379 		return -EPERM;
380 	if (!ops || !ops->pr_release)
381 		return -EOPNOTSUPP;
382 	if (copy_from_user(&rsv, arg, sizeof(rsv)))
383 		return -EFAULT;
384 
385 	if (rsv.flags)
386 		return -EOPNOTSUPP;
387 	return ops->pr_release(bdev, rsv.key, rsv.type);
388 }
389 
390 static int blkdev_pr_preempt(struct block_device *bdev, blk_mode_t mode,
391 		struct pr_preempt __user *arg, bool abort)
392 {
393 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
394 	struct pr_preempt p;
395 
396 	if (!blkdev_pr_allowed(bdev, mode))
397 		return -EPERM;
398 	if (!ops || !ops->pr_preempt)
399 		return -EOPNOTSUPP;
400 	if (copy_from_user(&p, arg, sizeof(p)))
401 		return -EFAULT;
402 
403 	if (p.flags)
404 		return -EOPNOTSUPP;
405 	return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);
406 }
407 
408 static int blkdev_pr_clear(struct block_device *bdev, blk_mode_t mode,
409 		struct pr_clear __user *arg)
410 {
411 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
412 	struct pr_clear c;
413 
414 	if (!blkdev_pr_allowed(bdev, mode))
415 		return -EPERM;
416 	if (!ops || !ops->pr_clear)
417 		return -EOPNOTSUPP;
418 	if (copy_from_user(&c, arg, sizeof(c)))
419 		return -EFAULT;
420 
421 	if (c.flags)
422 		return -EOPNOTSUPP;
423 	return ops->pr_clear(bdev, c.key);
424 }
425 
426 static int blkdev_pr_read_keys(struct block_device *bdev, blk_mode_t mode,
427 		struct pr_read_keys __user *arg)
428 {
429 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
430 	struct pr_keys *keys_info;
431 	struct pr_read_keys read_keys;
432 	u64 __user *keys_ptr;
433 	size_t keys_info_len;
434 	size_t keys_copy_len;
435 	int ret;
436 
437 	if (!blkdev_pr_allowed(bdev, mode))
438 		return -EPERM;
439 	if (!ops || !ops->pr_read_keys)
440 		return -EOPNOTSUPP;
441 
442 	if (copy_from_user(&read_keys, arg, sizeof(read_keys)))
443 		return -EFAULT;
444 
445 	if (read_keys.num_keys > PR_KEYS_MAX)
446 		return -EINVAL;
447 
448 	keys_info_len = struct_size(keys_info, keys, read_keys.num_keys);
449 
450 	keys_info = kvzalloc(keys_info_len, GFP_KERNEL);
451 	if (!keys_info)
452 		return -ENOMEM;
453 
454 	keys_info->num_keys = read_keys.num_keys;
455 
456 	ret = ops->pr_read_keys(bdev, keys_info);
457 	if (ret)
458 		goto out;
459 
460 	/* Copy out individual keys */
461 	keys_ptr = u64_to_user_ptr(read_keys.keys_ptr);
462 	keys_copy_len = min(read_keys.num_keys, keys_info->num_keys) *
463 		        sizeof(keys_info->keys[0]);
464 
465 	if (copy_to_user(keys_ptr, keys_info->keys, keys_copy_len)) {
466 		ret = -EFAULT;
467 		goto out;
468 	}
469 
470 	/* Copy out the arg struct */
471 	read_keys.generation = keys_info->generation;
472 	read_keys.num_keys = keys_info->num_keys;
473 
474 	if (copy_to_user(arg, &read_keys, sizeof(read_keys)))
475 		ret = -EFAULT;
476 out:
477 	kvfree(keys_info);
478 	return ret;
479 }
480 
481 static int blkdev_pr_read_reservation(struct block_device *bdev,
482 		blk_mode_t mode, struct pr_read_reservation __user *arg)
483 {
484 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
485 	struct pr_held_reservation rsv = {};
486 	struct pr_read_reservation out = {};
487 	int ret;
488 
489 	if (!blkdev_pr_allowed(bdev, mode))
490 		return -EPERM;
491 	if (!ops || !ops->pr_read_reservation)
492 		return -EOPNOTSUPP;
493 
494 	ret = ops->pr_read_reservation(bdev, &rsv);
495 	if (ret)
496 		return ret;
497 
498 	out.key = rsv.key;
499 	out.generation = rsv.generation;
500 	out.type = rsv.type;
501 
502 	if (copy_to_user(arg, &out, sizeof(out)))
503 		return -EFAULT;
504 	return 0;
505 }
506 
507 static int blkdev_flushbuf(struct block_device *bdev, unsigned cmd,
508 		unsigned long arg)
509 {
510 	if (!capable(CAP_SYS_ADMIN))
511 		return -EACCES;
512 
513 	mutex_lock(&bdev->bd_holder_lock);
514 	if (bdev->bd_holder_ops && bdev->bd_holder_ops->sync)
515 		bdev->bd_holder_ops->sync(bdev);
516 	else {
517 		mutex_unlock(&bdev->bd_holder_lock);
518 		sync_blockdev(bdev);
519 	}
520 
521 	invalidate_bdev(bdev);
522 	return 0;
523 }
524 
525 static int blkdev_roset(struct block_device *bdev, unsigned cmd,
526 		unsigned long arg)
527 {
528 	int ret, n;
529 
530 	if (!capable(CAP_SYS_ADMIN))
531 		return -EACCES;
532 
533 	if (get_user(n, (int __user *)arg))
534 		return -EFAULT;
535 	if (bdev->bd_disk->fops->set_read_only) {
536 		ret = bdev->bd_disk->fops->set_read_only(bdev, n);
537 		if (ret)
538 			return ret;
539 	}
540 	if (n)
541 		bdev_set_flag(bdev, BD_READ_ONLY);
542 	else
543 		bdev_clear_flag(bdev, BD_READ_ONLY);
544 	return 0;
545 }
546 
547 static int blkdev_getgeo(struct block_device *bdev,
548 		struct hd_geometry __user *argp)
549 {
550 	struct gendisk *disk = bdev->bd_disk;
551 	struct hd_geometry geo;
552 	int ret;
553 
554 	if (!argp)
555 		return -EINVAL;
556 	if (!disk->fops->getgeo)
557 		return -ENOTTY;
558 
559 	/*
560 	 * We need to set the startsect first, the driver may
561 	 * want to override it.
562 	 */
563 	memset(&geo, 0, sizeof(geo));
564 	geo.start = get_start_sect(bdev);
565 	ret = disk->fops->getgeo(disk, &geo);
566 	if (ret)
567 		return ret;
568 	if (copy_to_user(argp, &geo, sizeof(geo)))
569 		return -EFAULT;
570 	return 0;
571 }
572 
573 #ifdef CONFIG_COMPAT
574 struct compat_hd_geometry {
575 	unsigned char heads;
576 	unsigned char sectors;
577 	unsigned short cylinders;
578 	u32 start;
579 };
580 
581 static int compat_hdio_getgeo(struct block_device *bdev,
582 			      struct compat_hd_geometry __user *ugeo)
583 {
584 	struct gendisk *disk = bdev->bd_disk;
585 	struct hd_geometry geo;
586 	int ret;
587 
588 	if (!ugeo)
589 		return -EINVAL;
590 	if (!disk->fops->getgeo)
591 		return -ENOTTY;
592 
593 	memset(&geo, 0, sizeof(geo));
594 	/*
595 	 * We need to set the startsect first, the driver may
596 	 * want to override it.
597 	 */
598 	geo.start = get_start_sect(bdev);
599 	ret = disk->fops->getgeo(disk, &geo);
600 	if (ret)
601 		return ret;
602 
603 	ret = copy_to_user(ugeo, &geo, 4);
604 	ret |= put_user(geo.start, &ugeo->start);
605 	if (ret)
606 		ret = -EFAULT;
607 
608 	return ret;
609 }
610 #endif
611 
612 /* set the logical block size */
613 static int blkdev_bszset(struct file *file, blk_mode_t mode,
614 		int __user *argp)
615 {
616 	// this one might be file_inode(file)->i_rdev - a rare valid
617 	// use of file_inode() for those.
618 	dev_t dev = I_BDEV(file->f_mapping->host)->bd_dev;
619 	struct file *excl_file;
620 	int ret, n;
621 
622 	if (!capable(CAP_SYS_ADMIN))
623 		return -EACCES;
624 	if (!argp)
625 		return -EINVAL;
626 	if (get_user(n, argp))
627 		return -EFAULT;
628 
629 	if (mode & BLK_OPEN_EXCL)
630 		return set_blocksize(file, n);
631 
632 	excl_file = bdev_file_open_by_dev(dev, mode, &dev, NULL);
633 	if (IS_ERR(excl_file))
634 		return -EBUSY;
635 	ret = set_blocksize(excl_file, n);
636 	fput(excl_file);
637 	return ret;
638 }
639 
640 /*
641  * Common commands that are handled the same way on native and compat
642  * user space. Note the separate arg/argp parameters that are needed
643  * to deal with the compat_ptr() conversion.
644  */
645 static int blkdev_common_ioctl(struct block_device *bdev, blk_mode_t mode,
646 			       unsigned int cmd, unsigned long arg,
647 			       void __user *argp)
648 {
649 	unsigned int max_sectors;
650 
651 	switch (cmd) {
652 	case BLKFLSBUF:
653 		return blkdev_flushbuf(bdev, cmd, arg);
654 	case BLKROSET:
655 		return blkdev_roset(bdev, cmd, arg);
656 	case BLKDISCARD:
657 		return blk_ioctl_discard(bdev, mode, arg);
658 	case BLKSECDISCARD:
659 		return blk_ioctl_secure_erase(bdev, mode, argp);
660 	case BLKZEROOUT:
661 		return blk_ioctl_zeroout(bdev, mode, arg);
662 	case BLKGETDISKSEQ:
663 		return put_u64(argp, bdev->bd_disk->diskseq);
664 	case BLKREPORTZONE:
665 	case BLKREPORTZONEV2:
666 		return blkdev_report_zones_ioctl(bdev, cmd, arg);
667 	case BLKRESETZONE:
668 	case BLKOPENZONE:
669 	case BLKCLOSEZONE:
670 	case BLKFINISHZONE:
671 		return blkdev_zone_mgmt_ioctl(bdev, mode, cmd, arg);
672 	case BLKGETZONESZ:
673 		return put_uint(argp, bdev_zone_sectors(bdev));
674 	case BLKGETNRZONES:
675 		return put_uint(argp, bdev_nr_zones(bdev));
676 	case BLKROGET:
677 		return put_int(argp, bdev_read_only(bdev) != 0);
678 	case BLKSSZGET: /* get block device logical block size */
679 		return put_int(argp, bdev_logical_block_size(bdev));
680 	case BLKPBSZGET: /* get block device physical block size */
681 		return put_uint(argp, bdev_physical_block_size(bdev));
682 	case BLKIOMIN:
683 		return put_uint(argp, bdev_io_min(bdev));
684 	case BLKIOOPT:
685 		return put_uint(argp, bdev_io_opt(bdev));
686 	case BLKALIGNOFF:
687 		return put_int(argp, bdev_alignment_offset(bdev));
688 	case BLKDISCARDZEROES:
689 		return put_uint(argp, 0);
690 	case BLKSECTGET:
691 		max_sectors = min_t(unsigned int, USHRT_MAX,
692 				    queue_max_sectors(bdev_get_queue(bdev)));
693 		return put_ushort(argp, max_sectors);
694 	case BLKROTATIONAL:
695 		return put_ushort(argp, !bdev_nonrot(bdev));
696 	case BLKRASET:
697 	case BLKFRASET:
698 		if(!capable(CAP_SYS_ADMIN))
699 			return -EACCES;
700 		bdev->bd_disk->bdi->ra_pages = (arg * 512) / PAGE_SIZE;
701 		return 0;
702 	case BLKRRPART:
703 		if (!capable(CAP_SYS_ADMIN))
704 			return -EACCES;
705 		if (bdev_is_partition(bdev))
706 			return -EINVAL;
707 		return disk_scan_partitions(bdev->bd_disk,
708 				mode | BLK_OPEN_STRICT_SCAN);
709 	case BLKTRACESTART:
710 	case BLKTRACESTOP:
711 	case BLKTRACETEARDOWN:
712 		return blk_trace_ioctl(bdev, cmd, argp);
713 	case BLKCRYPTOIMPORTKEY:
714 	case BLKCRYPTOGENERATEKEY:
715 	case BLKCRYPTOPREPAREKEY:
716 		return blk_crypto_ioctl(bdev, cmd, argp);
717 	case IOC_PR_REGISTER:
718 		return blkdev_pr_register(bdev, mode, argp);
719 	case IOC_PR_RESERVE:
720 		return blkdev_pr_reserve(bdev, mode, argp);
721 	case IOC_PR_RELEASE:
722 		return blkdev_pr_release(bdev, mode, argp);
723 	case IOC_PR_PREEMPT:
724 		return blkdev_pr_preempt(bdev, mode, argp, false);
725 	case IOC_PR_PREEMPT_ABORT:
726 		return blkdev_pr_preempt(bdev, mode, argp, true);
727 	case IOC_PR_CLEAR:
728 		return blkdev_pr_clear(bdev, mode, argp);
729 	case IOC_PR_READ_KEYS:
730 		return blkdev_pr_read_keys(bdev, mode, argp);
731 	case IOC_PR_READ_RESERVATION:
732 		return blkdev_pr_read_reservation(bdev, mode, argp);
733 	default:
734 		return blk_get_meta_cap(bdev, cmd, argp);
735 	}
736 }
737 
738 /*
739  * Always keep this in sync with compat_blkdev_ioctl()
740  * to handle all incompatible commands in both functions.
741  *
742  * New commands must be compatible and go into blkdev_common_ioctl
743  */
744 long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
745 {
746 	struct block_device *bdev = I_BDEV(file->f_mapping->host);
747 	void __user *argp = (void __user *)arg;
748 	blk_mode_t mode = file_to_blk_mode(file);
749 	int ret;
750 
751 	switch (cmd) {
752 	/* These need separate implementations for the data structure */
753 	case HDIO_GETGEO:
754 		return blkdev_getgeo(bdev, argp);
755 	case BLKPG:
756 		return blkpg_ioctl(bdev, argp);
757 
758 	/* Compat mode returns 32-bit data instead of 'long' */
759 	case BLKRAGET:
760 	case BLKFRAGET:
761 		if (!argp)
762 			return -EINVAL;
763 		return put_long(argp,
764 			(bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
765 	case BLKGETSIZE:
766 		if (bdev_nr_sectors(bdev) > ~0UL)
767 			return -EFBIG;
768 		return put_ulong(argp, bdev_nr_sectors(bdev));
769 
770 	/* The data is compatible, but the command number is different */
771 	case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
772 		return put_int(argp, block_size(bdev));
773 	case BLKBSZSET:
774 		return blkdev_bszset(file, mode, argp);
775 	case BLKGETSIZE64:
776 		return put_u64(argp, bdev_nr_bytes(bdev));
777 
778 	/* Incompatible alignment on i386 */
779 	case BLKTRACESETUP:
780 	case BLKTRACESETUP2:
781 		return blk_trace_ioctl(bdev, cmd, argp);
782 	default:
783 		break;
784 	}
785 
786 	ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
787 	if (ret != -ENOIOCTLCMD)
788 		return ret;
789 
790 	if (!bdev->bd_disk->fops->ioctl)
791 		return -ENOTTY;
792 	return bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
793 }
794 
795 #ifdef CONFIG_COMPAT
796 
797 #define BLKBSZGET_32		_IOR(0x12, 112, int)
798 #define BLKBSZSET_32		_IOW(0x12, 113, int)
799 #define BLKGETSIZE64_32		_IOR(0x12, 114, int)
800 
801 /* Most of the generic ioctls are handled in the normal fallback path.
802    This assumes the blkdev's low level compat_ioctl always returns
803    ENOIOCTLCMD for unknown ioctls. */
804 long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
805 {
806 	int ret;
807 	void __user *argp = compat_ptr(arg);
808 	struct block_device *bdev = I_BDEV(file->f_mapping->host);
809 	struct gendisk *disk = bdev->bd_disk;
810 	blk_mode_t mode = file_to_blk_mode(file);
811 
812 	switch (cmd) {
813 	/* These need separate implementations for the data structure */
814 	case HDIO_GETGEO:
815 		return compat_hdio_getgeo(bdev, argp);
816 	case BLKPG:
817 		return compat_blkpg_ioctl(bdev, argp);
818 
819 	/* Compat mode returns 32-bit data instead of 'long' */
820 	case BLKRAGET:
821 	case BLKFRAGET:
822 		if (!argp)
823 			return -EINVAL;
824 		return compat_put_long(argp,
825 			(bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
826 	case BLKGETSIZE:
827 		if (bdev_nr_sectors(bdev) > ~(compat_ulong_t)0)
828 			return -EFBIG;
829 		return compat_put_ulong(argp, bdev_nr_sectors(bdev));
830 
831 	/* The data is compatible, but the command number is different */
832 	case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */
833 		return put_int(argp, bdev_logical_block_size(bdev));
834 	case BLKBSZSET_32:
835 		return blkdev_bszset(file, mode, argp);
836 	case BLKGETSIZE64_32:
837 		return put_u64(argp, bdev_nr_bytes(bdev));
838 
839 	/* Incompatible alignment on i386 */
840 	case BLKTRACESETUP32:
841 		return blk_trace_ioctl(bdev, cmd, argp);
842 	default:
843 		break;
844 	}
845 
846 	ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
847 	if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl)
848 		ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg);
849 
850 	return ret;
851 }
852 #endif
853 
854 struct blk_iou_cmd {
855 	int res;
856 	bool nowait;
857 };
858 
859 static void blk_cmd_complete(struct io_tw_req tw_req, io_tw_token_t tw)
860 {
861 	struct io_uring_cmd *cmd = io_uring_cmd_from_tw(tw_req);
862 	struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
863 
864 	if (bic->res == -EAGAIN && bic->nowait)
865 		io_uring_cmd_issue_blocking(cmd);
866 	else
867 		io_uring_cmd_done(cmd, bic->res,
868 				  IO_URING_CMD_TASK_WORK_ISSUE_FLAGS);
869 }
870 
871 static void bio_cmd_bio_end_io(struct bio *bio)
872 {
873 	struct io_uring_cmd *cmd = bio->bi_private;
874 	struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
875 
876 	if (unlikely(bio->bi_status) && !bic->res)
877 		bic->res = blk_status_to_errno(bio->bi_status);
878 
879 	io_uring_cmd_do_in_task_lazy(cmd, blk_cmd_complete);
880 	bio_put(bio);
881 }
882 
883 static int blkdev_cmd_discard(struct io_uring_cmd *cmd,
884 			      struct block_device *bdev,
885 			      uint64_t start, uint64_t len, bool nowait)
886 {
887 	struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
888 	gfp_t gfp = nowait ? GFP_NOWAIT : GFP_KERNEL;
889 	sector_t sector = start >> SECTOR_SHIFT;
890 	sector_t nr_sects = len >> SECTOR_SHIFT;
891 	struct bio *prev = NULL, *bio;
892 	int err;
893 
894 	if (!bdev_max_discard_sectors(bdev))
895 		return -EOPNOTSUPP;
896 	if (!(file_to_blk_mode(cmd->file) & BLK_OPEN_WRITE))
897 		return -EBADF;
898 	if (bdev_read_only(bdev))
899 		return -EPERM;
900 	err = blk_validate_byte_range(bdev, start, len);
901 	if (err)
902 		return err;
903 
904 	err = filemap_invalidate_pages(bdev->bd_mapping, start,
905 					start + len - 1, nowait);
906 	if (err)
907 		return err;
908 
909 	while (true) {
910 		bio = blk_alloc_discard_bio(bdev, &sector, &nr_sects, gfp);
911 		if (!bio)
912 			break;
913 		if (nowait) {
914 			/*
915 			 * Don't allow multi-bio non-blocking submissions as
916 			 * subsequent bios may fail but we won't get a direct
917 			 * indication of that. Normally, the caller should
918 			 * retry from a blocking context.
919 			 */
920 			if (unlikely(nr_sects)) {
921 				bio_put(bio);
922 				return -EAGAIN;
923 			}
924 			bio->bi_opf |= REQ_NOWAIT;
925 		}
926 
927 		prev = bio_chain_and_submit(prev, bio);
928 	}
929 	if (unlikely(!prev))
930 		return -EAGAIN;
931 	if (unlikely(nr_sects))
932 		bic->res = -EAGAIN;
933 
934 	prev->bi_private = cmd;
935 	prev->bi_end_io = bio_cmd_bio_end_io;
936 	submit_bio(prev);
937 	return -EIOCBQUEUED;
938 }
939 
940 int blkdev_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
941 {
942 	struct block_device *bdev = I_BDEV(cmd->file->f_mapping->host);
943 	struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
944 	const struct io_uring_sqe *sqe = cmd->sqe;
945 	u32 cmd_op = cmd->cmd_op;
946 	uint64_t start, len;
947 
948 	if (unlikely(sqe->ioprio || sqe->__pad1 || sqe->len ||
949 		     sqe->rw_flags || sqe->file_index))
950 		return -EINVAL;
951 
952 	bic->res = 0;
953 	bic->nowait = issue_flags & IO_URING_F_NONBLOCK;
954 
955 	start = READ_ONCE(sqe->addr);
956 	len = READ_ONCE(sqe->addr3);
957 
958 	switch (cmd_op) {
959 	case BLOCK_URING_CMD_DISCARD:
960 		return blkdev_cmd_discard(cmd, bdev, start, len, bic->nowait);
961 	}
962 	return -EINVAL;
963 }
964