xref: /linux/block/ioctl.c (revision 7deea5634a67700d04c2a0e6d2ffa0e2956fe8ad)
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 #include "blk-crypto-internal.h"
19 
blkpg_do_ioctl(struct block_device * bdev,struct blkpg_partition __user * upart,int op)20 static int blkpg_do_ioctl(struct block_device *bdev,
21 			  struct blkpg_partition __user *upart, int op)
22 {
23 	struct gendisk *disk = bdev->bd_disk;
24 	struct blkpg_partition p;
25 	sector_t start, length, capacity, end;
26 
27 	if (!capable(CAP_SYS_ADMIN))
28 		return -EACCES;
29 	if (copy_from_user(&p, upart, sizeof(struct blkpg_partition)))
30 		return -EFAULT;
31 	if (bdev_is_partition(bdev))
32 		return -EINVAL;
33 
34 	if (p.pno <= 0)
35 		return -EINVAL;
36 
37 	if (op == BLKPG_DEL_PARTITION)
38 		return bdev_del_partition(disk, p.pno);
39 
40 	if (p.start < 0 || p.length <= 0 || LLONG_MAX - p.length < p.start)
41 		return -EINVAL;
42 	/* Check that the partition is aligned to the block size */
43 	if (!IS_ALIGNED(p.start | p.length, bdev_logical_block_size(bdev)))
44 		return -EINVAL;
45 
46 	start = p.start >> SECTOR_SHIFT;
47 	length = p.length >> SECTOR_SHIFT;
48 	capacity = get_capacity(disk);
49 
50 	if (check_add_overflow(start, length, &end))
51 		return -EINVAL;
52 
53 	if (start >= capacity || end > capacity)
54 		return -EINVAL;
55 
56 	switch (op) {
57 	case BLKPG_ADD_PARTITION:
58 		return bdev_add_partition(disk, p.pno, start, length);
59 	case BLKPG_RESIZE_PARTITION:
60 		return bdev_resize_partition(disk, p.pno, start, length);
61 	default:
62 		return -EINVAL;
63 	}
64 }
65 
blkpg_ioctl(struct block_device * bdev,struct blkpg_ioctl_arg __user * arg)66 static int blkpg_ioctl(struct block_device *bdev,
67 		       struct blkpg_ioctl_arg __user *arg)
68 {
69 	struct blkpg_partition __user *udata;
70 	int op;
71 
72 	if (get_user(op, &arg->op) || get_user(udata, &arg->data))
73 		return -EFAULT;
74 
75 	return blkpg_do_ioctl(bdev, udata, op);
76 }
77 
78 #ifdef CONFIG_COMPAT
79 struct compat_blkpg_ioctl_arg {
80 	compat_int_t op;
81 	compat_int_t flags;
82 	compat_int_t datalen;
83 	compat_caddr_t data;
84 };
85 
compat_blkpg_ioctl(struct block_device * bdev,struct compat_blkpg_ioctl_arg __user * arg)86 static int compat_blkpg_ioctl(struct block_device *bdev,
87 			      struct compat_blkpg_ioctl_arg __user *arg)
88 {
89 	compat_caddr_t udata;
90 	int op;
91 
92 	if (get_user(op, &arg->op) || get_user(udata, &arg->data))
93 		return -EFAULT;
94 
95 	return blkpg_do_ioctl(bdev, compat_ptr(udata), op);
96 }
97 #endif
98 
99 /*
100  * Check that [start, start + len) is a valid range from the block device's
101  * perspective, including verifying that it can be correctly translated into
102  * logical block addresses.
103  */
blk_validate_byte_range(struct block_device * bdev,uint64_t start,uint64_t len)104 static int blk_validate_byte_range(struct block_device *bdev,
105 				   uint64_t start, uint64_t len)
106 {
107 	unsigned int bs_mask = bdev_logical_block_size(bdev) - 1;
108 	uint64_t end;
109 
110 	if ((start | len) & bs_mask)
111 		return -EINVAL;
112 	if (!len)
113 		return -EINVAL;
114 	if (check_add_overflow(start, len, &end) || end > bdev_nr_bytes(bdev))
115 		return -EINVAL;
116 
117 	return 0;
118 }
119 
blk_ioctl_discard(struct block_device * bdev,blk_mode_t mode,unsigned long arg)120 static int blk_ioctl_discard(struct block_device *bdev, blk_mode_t mode,
121 		unsigned long arg)
122 {
123 	uint64_t range[2], start, len;
124 	struct bio *prev = NULL, *bio;
125 	sector_t sector, nr_sects;
126 	struct blk_plug plug;
127 	int err;
128 
129 	if (copy_from_user(range, (void __user *)arg, sizeof(range)))
130 		return -EFAULT;
131 	start = range[0];
132 	len = range[1];
133 
134 	if (!bdev_max_discard_sectors(bdev))
135 		return -EOPNOTSUPP;
136 
137 	if (!(mode & BLK_OPEN_WRITE))
138 		return -EBADF;
139 	if (bdev_read_only(bdev))
140 		return -EPERM;
141 	err = blk_validate_byte_range(bdev, start, len);
142 	if (err)
143 		return err;
144 
145 	inode_lock(bdev->bd_mapping->host);
146 	filemap_invalidate_lock(bdev->bd_mapping);
147 	err = truncate_bdev_range(bdev, mode, start, start + len - 1);
148 	if (err)
149 		goto fail;
150 
151 	sector = start >> SECTOR_SHIFT;
152 	nr_sects = len >> SECTOR_SHIFT;
153 
154 	blk_start_plug(&plug);
155 	while (1) {
156 		if (fatal_signal_pending(current)) {
157 			if (prev)
158 				bio_await_chain(prev);
159 			err = -EINTR;
160 			goto out_unplug;
161 		}
162 		bio = blk_alloc_discard_bio(bdev, &sector, &nr_sects,
163 				GFP_KERNEL);
164 		if (!bio)
165 			break;
166 		prev = bio_chain_and_submit(prev, bio);
167 	}
168 	if (prev) {
169 		err = submit_bio_wait(prev);
170 		if (err == -EOPNOTSUPP)
171 			err = 0;
172 		bio_put(prev);
173 	}
174 out_unplug:
175 	blk_finish_plug(&plug);
176 fail:
177 	filemap_invalidate_unlock(bdev->bd_mapping);
178 	inode_unlock(bdev->bd_mapping->host);
179 	return err;
180 }
181 
blk_ioctl_secure_erase(struct block_device * bdev,blk_mode_t mode,void __user * argp)182 static int blk_ioctl_secure_erase(struct block_device *bdev, blk_mode_t mode,
183 		void __user *argp)
184 {
185 	uint64_t start, len, end;
186 	uint64_t range[2];
187 	int err;
188 
189 	if (!(mode & BLK_OPEN_WRITE))
190 		return -EBADF;
191 	if (!bdev_max_secure_erase_sectors(bdev))
192 		return -EOPNOTSUPP;
193 	if (copy_from_user(range, argp, sizeof(range)))
194 		return -EFAULT;
195 
196 	start = range[0];
197 	len = range[1];
198 	if ((start & 511) || (len & 511))
199 		return -EINVAL;
200 	if (check_add_overflow(start, len, &end) ||
201 	    end > bdev_nr_bytes(bdev))
202 		return -EINVAL;
203 
204 	inode_lock(bdev->bd_mapping->host);
205 	filemap_invalidate_lock(bdev->bd_mapping);
206 	err = truncate_bdev_range(bdev, mode, start, end - 1);
207 	if (!err)
208 		err = blkdev_issue_secure_erase(bdev, start >> 9, len >> 9,
209 						GFP_KERNEL);
210 	filemap_invalidate_unlock(bdev->bd_mapping);
211 	inode_unlock(bdev->bd_mapping->host);
212 	return err;
213 }
214 
215 
blk_ioctl_zeroout(struct block_device * bdev,blk_mode_t mode,unsigned long arg)216 static int blk_ioctl_zeroout(struct block_device *bdev, blk_mode_t mode,
217 		unsigned long arg)
218 {
219 	uint64_t range[2];
220 	uint64_t start, end, len;
221 	int err;
222 
223 	if (!(mode & BLK_OPEN_WRITE))
224 		return -EBADF;
225 
226 	if (copy_from_user(range, (void __user *)arg, sizeof(range)))
227 		return -EFAULT;
228 
229 	start = range[0];
230 	len = range[1];
231 	end = start + len - 1;
232 
233 	if (start & 511)
234 		return -EINVAL;
235 	if (len & 511)
236 		return -EINVAL;
237 	if (end >= (uint64_t)bdev_nr_bytes(bdev))
238 		return -EINVAL;
239 	if (end < start)
240 		return -EINVAL;
241 
242 	/* Invalidate the page cache, including dirty pages */
243 	inode_lock(bdev->bd_mapping->host);
244 	filemap_invalidate_lock(bdev->bd_mapping);
245 	err = truncate_bdev_range(bdev, mode, start, end);
246 	if (err)
247 		goto fail;
248 
249 	err = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,
250 				   BLKDEV_ZERO_NOUNMAP | BLKDEV_ZERO_KILLABLE);
251 
252 fail:
253 	filemap_invalidate_unlock(bdev->bd_mapping);
254 	inode_unlock(bdev->bd_mapping->host);
255 	return err;
256 }
257 
put_ushort(unsigned short __user * argp,unsigned short val)258 static int put_ushort(unsigned short __user *argp, unsigned short val)
259 {
260 	return put_user(val, argp);
261 }
262 
put_int(int __user * argp,int val)263 static int put_int(int __user *argp, int val)
264 {
265 	return put_user(val, argp);
266 }
267 
put_uint(unsigned int __user * argp,unsigned int val)268 static int put_uint(unsigned int __user *argp, unsigned int val)
269 {
270 	return put_user(val, argp);
271 }
272 
put_long(long __user * argp,long val)273 static int put_long(long __user *argp, long val)
274 {
275 	return put_user(val, argp);
276 }
277 
put_ulong(unsigned long __user * argp,unsigned long val)278 static int put_ulong(unsigned long __user *argp, unsigned long val)
279 {
280 	return put_user(val, argp);
281 }
282 
put_u64(u64 __user * argp,u64 val)283 static int put_u64(u64 __user *argp, u64 val)
284 {
285 	return put_user(val, argp);
286 }
287 
288 #ifdef CONFIG_COMPAT
compat_put_long(compat_long_t __user * argp,long val)289 static int compat_put_long(compat_long_t __user *argp, long val)
290 {
291 	return put_user(val, argp);
292 }
293 
compat_put_ulong(compat_ulong_t __user * argp,compat_ulong_t val)294 static int compat_put_ulong(compat_ulong_t __user *argp, compat_ulong_t val)
295 {
296 	return put_user(val, argp);
297 }
298 #endif
299 
300 #ifdef CONFIG_COMPAT
301 /*
302  * This is the equivalent of compat_ptr_ioctl(), to be used by block
303  * drivers that implement only commands that are completely compatible
304  * between 32-bit and 64-bit user space
305  */
blkdev_compat_ptr_ioctl(struct block_device * bdev,blk_mode_t mode,unsigned cmd,unsigned long arg)306 int blkdev_compat_ptr_ioctl(struct block_device *bdev, blk_mode_t mode,
307 			unsigned cmd, unsigned long arg)
308 {
309 	struct gendisk *disk = bdev->bd_disk;
310 
311 	if (disk->fops->ioctl)
312 		return disk->fops->ioctl(bdev, mode, cmd,
313 					 (unsigned long)compat_ptr(arg));
314 
315 	return -ENOIOCTLCMD;
316 }
317 EXPORT_SYMBOL(blkdev_compat_ptr_ioctl);
318 #endif
319 
blkdev_pr_allowed(struct block_device * bdev,blk_mode_t mode)320 static bool blkdev_pr_allowed(struct block_device *bdev, blk_mode_t mode)
321 {
322 	/* no sense to make reservations for partitions */
323 	if (bdev_is_partition(bdev))
324 		return false;
325 
326 	if (capable(CAP_SYS_ADMIN))
327 		return true;
328 	/*
329 	 * Only allow unprivileged reservations if the file descriptor is open
330 	 * for writing.
331 	 */
332 	return mode & BLK_OPEN_WRITE;
333 }
334 
blkdev_pr_register(struct block_device * bdev,blk_mode_t mode,struct pr_registration __user * arg)335 static int blkdev_pr_register(struct block_device *bdev, blk_mode_t mode,
336 		struct pr_registration __user *arg)
337 {
338 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
339 	struct pr_registration reg;
340 
341 	if (!blkdev_pr_allowed(bdev, mode))
342 		return -EPERM;
343 	if (!ops || !ops->pr_register)
344 		return -EOPNOTSUPP;
345 	if (copy_from_user(&reg, arg, sizeof(reg)))
346 		return -EFAULT;
347 
348 	if (reg.flags & ~PR_FL_IGNORE_KEY)
349 		return -EOPNOTSUPP;
350 	return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);
351 }
352 
blkdev_pr_reserve(struct block_device * bdev,blk_mode_t mode,struct pr_reservation __user * arg)353 static int blkdev_pr_reserve(struct block_device *bdev, blk_mode_t mode,
354 		struct pr_reservation __user *arg)
355 {
356 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
357 	struct pr_reservation rsv;
358 
359 	if (!blkdev_pr_allowed(bdev, mode))
360 		return -EPERM;
361 	if (!ops || !ops->pr_reserve)
362 		return -EOPNOTSUPP;
363 	if (copy_from_user(&rsv, arg, sizeof(rsv)))
364 		return -EFAULT;
365 
366 	if (rsv.flags & ~PR_FL_IGNORE_KEY)
367 		return -EOPNOTSUPP;
368 	return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);
369 }
370 
blkdev_pr_release(struct block_device * bdev,blk_mode_t mode,struct pr_reservation __user * arg)371 static int blkdev_pr_release(struct block_device *bdev, blk_mode_t mode,
372 		struct pr_reservation __user *arg)
373 {
374 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
375 	struct pr_reservation rsv;
376 
377 	if (!blkdev_pr_allowed(bdev, mode))
378 		return -EPERM;
379 	if (!ops || !ops->pr_release)
380 		return -EOPNOTSUPP;
381 	if (copy_from_user(&rsv, arg, sizeof(rsv)))
382 		return -EFAULT;
383 
384 	if (rsv.flags)
385 		return -EOPNOTSUPP;
386 	return ops->pr_release(bdev, rsv.key, rsv.type);
387 }
388 
blkdev_pr_preempt(struct block_device * bdev,blk_mode_t mode,struct pr_preempt __user * arg,bool abort)389 static int blkdev_pr_preempt(struct block_device *bdev, blk_mode_t mode,
390 		struct pr_preempt __user *arg, bool abort)
391 {
392 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
393 	struct pr_preempt p;
394 
395 	if (!blkdev_pr_allowed(bdev, mode))
396 		return -EPERM;
397 	if (!ops || !ops->pr_preempt)
398 		return -EOPNOTSUPP;
399 	if (copy_from_user(&p, arg, sizeof(p)))
400 		return -EFAULT;
401 
402 	if (p.flags)
403 		return -EOPNOTSUPP;
404 	return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);
405 }
406 
blkdev_pr_clear(struct block_device * bdev,blk_mode_t mode,struct pr_clear __user * arg)407 static int blkdev_pr_clear(struct block_device *bdev, blk_mode_t mode,
408 		struct pr_clear __user *arg)
409 {
410 	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
411 	struct pr_clear c;
412 
413 	if (!blkdev_pr_allowed(bdev, mode))
414 		return -EPERM;
415 	if (!ops || !ops->pr_clear)
416 		return -EOPNOTSUPP;
417 	if (copy_from_user(&c, arg, sizeof(c)))
418 		return -EFAULT;
419 
420 	if (c.flags)
421 		return -EOPNOTSUPP;
422 	return ops->pr_clear(bdev, c.key);
423 }
424 
blkdev_flushbuf(struct block_device * bdev,unsigned cmd,unsigned long arg)425 static int blkdev_flushbuf(struct block_device *bdev, unsigned cmd,
426 		unsigned long arg)
427 {
428 	if (!capable(CAP_SYS_ADMIN))
429 		return -EACCES;
430 
431 	mutex_lock(&bdev->bd_holder_lock);
432 	if (bdev->bd_holder_ops && bdev->bd_holder_ops->sync)
433 		bdev->bd_holder_ops->sync(bdev);
434 	else {
435 		mutex_unlock(&bdev->bd_holder_lock);
436 		sync_blockdev(bdev);
437 	}
438 
439 	invalidate_bdev(bdev);
440 	return 0;
441 }
442 
blkdev_roset(struct block_device * bdev,unsigned cmd,unsigned long arg)443 static int blkdev_roset(struct block_device *bdev, unsigned cmd,
444 		unsigned long arg)
445 {
446 	int ret, n;
447 
448 	if (!capable(CAP_SYS_ADMIN))
449 		return -EACCES;
450 
451 	if (get_user(n, (int __user *)arg))
452 		return -EFAULT;
453 	if (bdev->bd_disk->fops->set_read_only) {
454 		ret = bdev->bd_disk->fops->set_read_only(bdev, n);
455 		if (ret)
456 			return ret;
457 	}
458 	if (n)
459 		bdev_set_flag(bdev, BD_READ_ONLY);
460 	else
461 		bdev_clear_flag(bdev, BD_READ_ONLY);
462 	return 0;
463 }
464 
blkdev_getgeo(struct block_device * bdev,struct hd_geometry __user * argp)465 static int blkdev_getgeo(struct block_device *bdev,
466 		struct hd_geometry __user *argp)
467 {
468 	struct gendisk *disk = bdev->bd_disk;
469 	struct hd_geometry geo;
470 	int ret;
471 
472 	if (!argp)
473 		return -EINVAL;
474 	if (!disk->fops->getgeo)
475 		return -ENOTTY;
476 
477 	/*
478 	 * We need to set the startsect first, the driver may
479 	 * want to override it.
480 	 */
481 	memset(&geo, 0, sizeof(geo));
482 	geo.start = get_start_sect(bdev);
483 	ret = disk->fops->getgeo(bdev, &geo);
484 	if (ret)
485 		return ret;
486 	if (copy_to_user(argp, &geo, sizeof(geo)))
487 		return -EFAULT;
488 	return 0;
489 }
490 
491 #ifdef CONFIG_COMPAT
492 struct compat_hd_geometry {
493 	unsigned char heads;
494 	unsigned char sectors;
495 	unsigned short cylinders;
496 	u32 start;
497 };
498 
compat_hdio_getgeo(struct block_device * bdev,struct compat_hd_geometry __user * ugeo)499 static int compat_hdio_getgeo(struct block_device *bdev,
500 			      struct compat_hd_geometry __user *ugeo)
501 {
502 	struct gendisk *disk = bdev->bd_disk;
503 	struct hd_geometry geo;
504 	int ret;
505 
506 	if (!ugeo)
507 		return -EINVAL;
508 	if (!disk->fops->getgeo)
509 		return -ENOTTY;
510 
511 	memset(&geo, 0, sizeof(geo));
512 	/*
513 	 * We need to set the startsect first, the driver may
514 	 * want to override it.
515 	 */
516 	geo.start = get_start_sect(bdev);
517 	ret = disk->fops->getgeo(bdev, &geo);
518 	if (ret)
519 		return ret;
520 
521 	ret = copy_to_user(ugeo, &geo, 4);
522 	ret |= put_user(geo.start, &ugeo->start);
523 	if (ret)
524 		ret = -EFAULT;
525 
526 	return ret;
527 }
528 #endif
529 
530 /* set the logical block size */
blkdev_bszset(struct file * file,blk_mode_t mode,int __user * argp)531 static int blkdev_bszset(struct file *file, blk_mode_t mode,
532 		int __user *argp)
533 {
534 	// this one might be file_inode(file)->i_rdev - a rare valid
535 	// use of file_inode() for those.
536 	dev_t dev = I_BDEV(file->f_mapping->host)->bd_dev;
537 	struct file *excl_file;
538 	int ret, n;
539 
540 	if (!capable(CAP_SYS_ADMIN))
541 		return -EACCES;
542 	if (!argp)
543 		return -EINVAL;
544 	if (get_user(n, argp))
545 		return -EFAULT;
546 
547 	if (mode & BLK_OPEN_EXCL)
548 		return set_blocksize(file, n);
549 
550 	excl_file = bdev_file_open_by_dev(dev, mode, &dev, NULL);
551 	if (IS_ERR(excl_file))
552 		return -EBUSY;
553 	ret = set_blocksize(excl_file, n);
554 	fput(excl_file);
555 	return ret;
556 }
557 
558 /*
559  * Common commands that are handled the same way on native and compat
560  * user space. Note the separate arg/argp parameters that are needed
561  * to deal with the compat_ptr() conversion.
562  */
blkdev_common_ioctl(struct block_device * bdev,blk_mode_t mode,unsigned int cmd,unsigned long arg,void __user * argp)563 static int blkdev_common_ioctl(struct block_device *bdev, blk_mode_t mode,
564 			       unsigned int cmd, unsigned long arg,
565 			       void __user *argp)
566 {
567 	unsigned int max_sectors;
568 
569 	switch (cmd) {
570 	case BLKFLSBUF:
571 		return blkdev_flushbuf(bdev, cmd, arg);
572 	case BLKROSET:
573 		return blkdev_roset(bdev, cmd, arg);
574 	case BLKDISCARD:
575 		return blk_ioctl_discard(bdev, mode, arg);
576 	case BLKSECDISCARD:
577 		return blk_ioctl_secure_erase(bdev, mode, argp);
578 	case BLKZEROOUT:
579 		return blk_ioctl_zeroout(bdev, mode, arg);
580 	case BLKGETDISKSEQ:
581 		return put_u64(argp, bdev->bd_disk->diskseq);
582 	case BLKREPORTZONE:
583 		return blkdev_report_zones_ioctl(bdev, cmd, arg);
584 	case BLKRESETZONE:
585 	case BLKOPENZONE:
586 	case BLKCLOSEZONE:
587 	case BLKFINISHZONE:
588 		return blkdev_zone_mgmt_ioctl(bdev, mode, cmd, arg);
589 	case BLKGETZONESZ:
590 		return put_uint(argp, bdev_zone_sectors(bdev));
591 	case BLKGETNRZONES:
592 		return put_uint(argp, bdev_nr_zones(bdev));
593 	case BLKROGET:
594 		return put_int(argp, bdev_read_only(bdev) != 0);
595 	case BLKSSZGET: /* get block device logical block size */
596 		return put_int(argp, bdev_logical_block_size(bdev));
597 	case BLKPBSZGET: /* get block device physical block size */
598 		return put_uint(argp, bdev_physical_block_size(bdev));
599 	case BLKIOMIN:
600 		return put_uint(argp, bdev_io_min(bdev));
601 	case BLKIOOPT:
602 		return put_uint(argp, bdev_io_opt(bdev));
603 	case BLKALIGNOFF:
604 		return put_int(argp, bdev_alignment_offset(bdev));
605 	case BLKDISCARDZEROES:
606 		return put_uint(argp, 0);
607 	case BLKSECTGET:
608 		max_sectors = min_t(unsigned int, USHRT_MAX,
609 				    queue_max_sectors(bdev_get_queue(bdev)));
610 		return put_ushort(argp, max_sectors);
611 	case BLKROTATIONAL:
612 		return put_ushort(argp, !bdev_nonrot(bdev));
613 	case BLKRASET:
614 	case BLKFRASET:
615 		if(!capable(CAP_SYS_ADMIN))
616 			return -EACCES;
617 		bdev->bd_disk->bdi->ra_pages = (arg * 512) / PAGE_SIZE;
618 		return 0;
619 	case BLKRRPART:
620 		if (!capable(CAP_SYS_ADMIN))
621 			return -EACCES;
622 		if (bdev_is_partition(bdev))
623 			return -EINVAL;
624 		return disk_scan_partitions(bdev->bd_disk,
625 				mode | BLK_OPEN_STRICT_SCAN);
626 	case BLKTRACESTART:
627 	case BLKTRACESTOP:
628 	case BLKTRACETEARDOWN:
629 		return blk_trace_ioctl(bdev, cmd, argp);
630 	case BLKCRYPTOIMPORTKEY:
631 	case BLKCRYPTOGENERATEKEY:
632 	case BLKCRYPTOPREPAREKEY:
633 		return blk_crypto_ioctl(bdev, cmd, argp);
634 	case IOC_PR_REGISTER:
635 		return blkdev_pr_register(bdev, mode, argp);
636 	case IOC_PR_RESERVE:
637 		return blkdev_pr_reserve(bdev, mode, argp);
638 	case IOC_PR_RELEASE:
639 		return blkdev_pr_release(bdev, mode, argp);
640 	case IOC_PR_PREEMPT:
641 		return blkdev_pr_preempt(bdev, mode, argp, false);
642 	case IOC_PR_PREEMPT_ABORT:
643 		return blkdev_pr_preempt(bdev, mode, argp, true);
644 	case IOC_PR_CLEAR:
645 		return blkdev_pr_clear(bdev, mode, argp);
646 	default:
647 		return -ENOIOCTLCMD;
648 	}
649 }
650 
651 /*
652  * Always keep this in sync with compat_blkdev_ioctl()
653  * to handle all incompatible commands in both functions.
654  *
655  * New commands must be compatible and go into blkdev_common_ioctl
656  */
blkdev_ioctl(struct file * file,unsigned cmd,unsigned long arg)657 long blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
658 {
659 	struct block_device *bdev = I_BDEV(file->f_mapping->host);
660 	void __user *argp = (void __user *)arg;
661 	blk_mode_t mode = file_to_blk_mode(file);
662 	int ret;
663 
664 	switch (cmd) {
665 	/* These need separate implementations for the data structure */
666 	case HDIO_GETGEO:
667 		return blkdev_getgeo(bdev, argp);
668 	case BLKPG:
669 		return blkpg_ioctl(bdev, argp);
670 
671 	/* Compat mode returns 32-bit data instead of 'long' */
672 	case BLKRAGET:
673 	case BLKFRAGET:
674 		if (!argp)
675 			return -EINVAL;
676 		return put_long(argp,
677 			(bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
678 	case BLKGETSIZE:
679 		if (bdev_nr_sectors(bdev) > ~0UL)
680 			return -EFBIG;
681 		return put_ulong(argp, bdev_nr_sectors(bdev));
682 
683 	/* The data is compatible, but the command number is different */
684 	case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
685 		return put_int(argp, block_size(bdev));
686 	case BLKBSZSET:
687 		return blkdev_bszset(file, mode, argp);
688 	case BLKGETSIZE64:
689 		return put_u64(argp, bdev_nr_bytes(bdev));
690 
691 	/* Incompatible alignment on i386 */
692 	case BLKTRACESETUP:
693 		return blk_trace_ioctl(bdev, cmd, argp);
694 	default:
695 		break;
696 	}
697 
698 	ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
699 	if (ret != -ENOIOCTLCMD)
700 		return ret;
701 
702 	if (!bdev->bd_disk->fops->ioctl)
703 		return -ENOTTY;
704 	return bdev->bd_disk->fops->ioctl(bdev, mode, cmd, arg);
705 }
706 
707 #ifdef CONFIG_COMPAT
708 
709 #define BLKBSZGET_32		_IOR(0x12, 112, int)
710 #define BLKBSZSET_32		_IOW(0x12, 113, int)
711 #define BLKGETSIZE64_32		_IOR(0x12, 114, int)
712 
713 /* Most of the generic ioctls are handled in the normal fallback path.
714    This assumes the blkdev's low level compat_ioctl always returns
715    ENOIOCTLCMD for unknown ioctls. */
compat_blkdev_ioctl(struct file * file,unsigned cmd,unsigned long arg)716 long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
717 {
718 	int ret;
719 	void __user *argp = compat_ptr(arg);
720 	struct block_device *bdev = I_BDEV(file->f_mapping->host);
721 	struct gendisk *disk = bdev->bd_disk;
722 	blk_mode_t mode = file_to_blk_mode(file);
723 
724 	switch (cmd) {
725 	/* These need separate implementations for the data structure */
726 	case HDIO_GETGEO:
727 		return compat_hdio_getgeo(bdev, argp);
728 	case BLKPG:
729 		return compat_blkpg_ioctl(bdev, argp);
730 
731 	/* Compat mode returns 32-bit data instead of 'long' */
732 	case BLKRAGET:
733 	case BLKFRAGET:
734 		if (!argp)
735 			return -EINVAL;
736 		return compat_put_long(argp,
737 			(bdev->bd_disk->bdi->ra_pages * PAGE_SIZE) / 512);
738 	case BLKGETSIZE:
739 		if (bdev_nr_sectors(bdev) > ~(compat_ulong_t)0)
740 			return -EFBIG;
741 		return compat_put_ulong(argp, bdev_nr_sectors(bdev));
742 
743 	/* The data is compatible, but the command number is different */
744 	case BLKBSZGET_32: /* get the logical block size (cf. BLKSSZGET) */
745 		return put_int(argp, bdev_logical_block_size(bdev));
746 	case BLKBSZSET_32:
747 		return blkdev_bszset(file, mode, argp);
748 	case BLKGETSIZE64_32:
749 		return put_u64(argp, bdev_nr_bytes(bdev));
750 
751 	/* Incompatible alignment on i386 */
752 	case BLKTRACESETUP32:
753 		return blk_trace_ioctl(bdev, cmd, argp);
754 	default:
755 		break;
756 	}
757 
758 	ret = blkdev_common_ioctl(bdev, mode, cmd, arg, argp);
759 	if (ret == -ENOIOCTLCMD && disk->fops->compat_ioctl)
760 		ret = disk->fops->compat_ioctl(bdev, mode, cmd, arg);
761 
762 	return ret;
763 }
764 #endif
765 
766 struct blk_iou_cmd {
767 	int res;
768 	bool nowait;
769 };
770 
blk_cmd_complete(struct io_uring_cmd * cmd,unsigned int issue_flags)771 static void blk_cmd_complete(struct io_uring_cmd *cmd, unsigned int issue_flags)
772 {
773 	struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
774 
775 	if (bic->res == -EAGAIN && bic->nowait)
776 		io_uring_cmd_issue_blocking(cmd);
777 	else
778 		io_uring_cmd_done(cmd, bic->res, 0, issue_flags);
779 }
780 
bio_cmd_bio_end_io(struct bio * bio)781 static void bio_cmd_bio_end_io(struct bio *bio)
782 {
783 	struct io_uring_cmd *cmd = bio->bi_private;
784 	struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
785 
786 	if (unlikely(bio->bi_status) && !bic->res)
787 		bic->res = blk_status_to_errno(bio->bi_status);
788 
789 	io_uring_cmd_do_in_task_lazy(cmd, blk_cmd_complete);
790 	bio_put(bio);
791 }
792 
blkdev_cmd_discard(struct io_uring_cmd * cmd,struct block_device * bdev,uint64_t start,uint64_t len,bool nowait)793 static int blkdev_cmd_discard(struct io_uring_cmd *cmd,
794 			      struct block_device *bdev,
795 			      uint64_t start, uint64_t len, bool nowait)
796 {
797 	struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
798 	gfp_t gfp = nowait ? GFP_NOWAIT : GFP_KERNEL;
799 	sector_t sector = start >> SECTOR_SHIFT;
800 	sector_t nr_sects = len >> SECTOR_SHIFT;
801 	struct bio *prev = NULL, *bio;
802 	int err;
803 
804 	if (!bdev_max_discard_sectors(bdev))
805 		return -EOPNOTSUPP;
806 	if (!(file_to_blk_mode(cmd->file) & BLK_OPEN_WRITE))
807 		return -EBADF;
808 	if (bdev_read_only(bdev))
809 		return -EPERM;
810 	err = blk_validate_byte_range(bdev, start, len);
811 	if (err)
812 		return err;
813 
814 	err = filemap_invalidate_pages(bdev->bd_mapping, start,
815 					start + len - 1, nowait);
816 	if (err)
817 		return err;
818 
819 	while (true) {
820 		bio = blk_alloc_discard_bio(bdev, &sector, &nr_sects, gfp);
821 		if (!bio)
822 			break;
823 		if (nowait) {
824 			/*
825 			 * Don't allow multi-bio non-blocking submissions as
826 			 * subsequent bios may fail but we won't get a direct
827 			 * indication of that. Normally, the caller should
828 			 * retry from a blocking context.
829 			 */
830 			if (unlikely(nr_sects)) {
831 				bio_put(bio);
832 				return -EAGAIN;
833 			}
834 			bio->bi_opf |= REQ_NOWAIT;
835 		}
836 
837 		prev = bio_chain_and_submit(prev, bio);
838 	}
839 	if (unlikely(!prev))
840 		return -EAGAIN;
841 	if (unlikely(nr_sects))
842 		bic->res = -EAGAIN;
843 
844 	prev->bi_private = cmd;
845 	prev->bi_end_io = bio_cmd_bio_end_io;
846 	submit_bio(prev);
847 	return -EIOCBQUEUED;
848 }
849 
blkdev_uring_cmd(struct io_uring_cmd * cmd,unsigned int issue_flags)850 int blkdev_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags)
851 {
852 	struct block_device *bdev = I_BDEV(cmd->file->f_mapping->host);
853 	struct blk_iou_cmd *bic = io_uring_cmd_to_pdu(cmd, struct blk_iou_cmd);
854 	const struct io_uring_sqe *sqe = cmd->sqe;
855 	u32 cmd_op = cmd->cmd_op;
856 	uint64_t start, len;
857 
858 	if (unlikely(sqe->ioprio || sqe->__pad1 || sqe->len ||
859 		     sqe->rw_flags || sqe->file_index))
860 		return -EINVAL;
861 
862 	bic->res = 0;
863 	bic->nowait = issue_flags & IO_URING_F_NONBLOCK;
864 
865 	start = READ_ONCE(sqe->addr);
866 	len = READ_ONCE(sqe->addr3);
867 
868 	switch (cmd_op) {
869 	case BLOCK_URING_CMD_DISCARD:
870 		return blkdev_cmd_discard(cmd, bdev, start, len, bic->nowait);
871 	}
872 	return -EINVAL;
873 }
874