1#include <linux/capability.h>
2#include <linux/blkdev.h>
3#include <linux/export.h>
4#include <linux/gfp.h>
5#include <linux/blkpg.h>
6#include <linux/hdreg.h>
7#include <linux/backing-dev.h>
8#include <linux/fs.h>
9#include <linux/blktrace_api.h>
10#include <linux/pr.h>
11#include <linux/uaccess.h>
12
13static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
14{
15 struct block_device *bdevp;
16 struct gendisk *disk;
17 struct hd_struct *part, *lpart;
18 struct blkpg_ioctl_arg a;
19 struct blkpg_partition p;
20 struct disk_part_iter piter;
21 long long start, length;
22 int partno;
23
24 if (!capable(CAP_SYS_ADMIN))
25 return -EACCES;
26 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
27 return -EFAULT;
28 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
29 return -EFAULT;
30 disk = bdev->bd_disk;
31 if (bdev != bdev->bd_contains)
32 return -EINVAL;
33 partno = p.pno;
34 if (partno <= 0)
35 return -EINVAL;
36 switch (a.op) {
37 case BLKPG_ADD_PARTITION:
38 start = p.start >> 9;
39 length = p.length >> 9;
40 /* check for fit in a hd_struct */
41 if (sizeof(sector_t) == sizeof(long) &&
42 sizeof(long long) > sizeof(long)) {
43 long pstart = start, plength = length;
44 if (pstart != start || plength != length
45 || pstart < 0 || plength < 0 || partno > 65535)
46 return -EINVAL;
47 }
48 /* check if partition is aligned to blocksize */
49 if (p.start & (bdev_logical_block_size(bdev) - 1))
50 return -EINVAL;
51
52 mutex_lock(&bdev->bd_mutex);
53
54 /* overlap? */
55 disk_part_iter_init(&piter, disk,
56 DISK_PITER_INCL_EMPTY);
57 while ((part = disk_part_iter_next(&piter))) {
58 if (!(start + length <= part->start_sect ||
59 start >= part->start_sect + part->nr_sects)) {
60 disk_part_iter_exit(&piter);
61 mutex_unlock(&bdev->bd_mutex);
62 return -EBUSY;
63 }
64 }
65 disk_part_iter_exit(&piter);
66
67 /* all seems OK */
68 part = add_partition(disk, partno, start, length,
69 ADDPART_FLAG_NONE, NULL);
70 mutex_unlock(&bdev->bd_mutex);
71 return PTR_ERR_OR_ZERO(part);
72 case BLKPG_DEL_PARTITION:
73 part = disk_get_part(disk, partno);
74 if (!part)
75 return -ENXIO;
76
77 bdevp = bdget(part_devt(part));
78 disk_put_part(part);
79 if (!bdevp)
80 return -ENOMEM;
81
82 mutex_lock(&bdevp->bd_mutex);
83 if (bdevp->bd_openers) {
84 mutex_unlock(&bdevp->bd_mutex);
85 bdput(bdevp);
86 return -EBUSY;
87 }
88 /* all seems OK */
89 fsync_bdev(bdevp);
90 invalidate_bdev(bdevp);
91
92 mutex_lock_nested(&bdev->bd_mutex, 1);
93 delete_partition(disk, partno);
94 mutex_unlock(&bdev->bd_mutex);
95 mutex_unlock(&bdevp->bd_mutex);
96 bdput(bdevp);
97
98 return 0;
99 case BLKPG_RESIZE_PARTITION:
100 start = p.start >> 9;
101 /* new length of partition in bytes */
102 length = p.length >> 9;
103 /* check for fit in a hd_struct */
104 if (sizeof(sector_t) == sizeof(long) &&
105 sizeof(long long) > sizeof(long)) {
106 long pstart = start, plength = length;
107 if (pstart != start || plength != length
108 || pstart < 0 || plength < 0)
109 return -EINVAL;
110 }
111 part = disk_get_part(disk, partno);
112 if (!part)
113 return -ENXIO;
114 bdevp = bdget(part_devt(part));
115 if (!bdevp) {
116 disk_put_part(part);
117 return -ENOMEM;
118 }
119 mutex_lock(&bdevp->bd_mutex);
120 mutex_lock_nested(&bdev->bd_mutex, 1);
121 if (start != part->start_sect) {
122 mutex_unlock(&bdevp->bd_mutex);
123 mutex_unlock(&bdev->bd_mutex);
124 bdput(bdevp);
125 disk_put_part(part);
126 return -EINVAL;
127 }
128 /* overlap? */
129 disk_part_iter_init(&piter, disk,
130 DISK_PITER_INCL_EMPTY);
131 while ((lpart = disk_part_iter_next(&piter))) {
132 if (lpart->partno != partno &&
133 !(start + length <= lpart->start_sect ||
134 start >= lpart->start_sect + lpart->nr_sects)
135 ) {
136 disk_part_iter_exit(&piter);
137 mutex_unlock(&bdevp->bd_mutex);
138 mutex_unlock(&bdev->bd_mutex);
139 bdput(bdevp);
140 disk_put_part(part);
141 return -EBUSY;
142 }
143 }
144 disk_part_iter_exit(&piter);
145 part_nr_sects_write(part, (sector_t)length);
146 i_size_write(bdevp->bd_inode, p.length);
147 mutex_unlock(&bdevp->bd_mutex);
148 mutex_unlock(&bdev->bd_mutex);
149 bdput(bdevp);
150 disk_put_part(part);
151 return 0;
152 default:
153 return -EINVAL;
154 }
155}
156
157/*
158 * This is an exported API for the block driver, and will not
159 * acquire bd_mutex. This API should be used in case that
160 * caller has held bd_mutex already.
161 */
162int __blkdev_reread_part(struct block_device *bdev)
163{
164 struct gendisk *disk = bdev->bd_disk;
165
166 if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains)
167 return -EINVAL;
168 if (!capable(CAP_SYS_ADMIN))
169 return -EACCES;
170
171 lockdep_assert_held(&bdev->bd_mutex);
172
173 return rescan_partitions(disk, bdev);
174}
175EXPORT_SYMBOL(__blkdev_reread_part);
176
177/*
178 * This is an exported API for the block driver, and will
179 * try to acquire bd_mutex. If bd_mutex has been held already
180 * in current context, please call __blkdev_reread_part().
181 *
182 * Make sure the held locks in current context aren't required
183 * in open()/close() handler and I/O path for avoiding ABBA deadlock:
184 * - bd_mutex is held before calling block driver's open/close
185 * handler
186 * - reading partition table may submit I/O to the block device
187 */
188int blkdev_reread_part(struct block_device *bdev)
189{
190 int res;
191
192 mutex_lock(&bdev->bd_mutex);
193 res = __blkdev_reread_part(bdev);
194 mutex_unlock(&bdev->bd_mutex);
195
196 return res;
197}
198EXPORT_SYMBOL(blkdev_reread_part);
199
200static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,
201 unsigned long arg, unsigned long flags)
202{
203 uint64_t range[2];
204 uint64_t start, len;
205 struct request_queue *q = bdev_get_queue(bdev);
206 struct address_space *mapping = bdev->bd_inode->i_mapping;
207
208
209 if (!(mode & FMODE_WRITE))
210 return -EBADF;
211
212 if (!blk_queue_discard(q))
213 return -EOPNOTSUPP;
214
215 if (copy_from_user(range, (void __user *)arg, sizeof(range)))
216 return -EFAULT;
217
218 start = range[0];
219 len = range[1];
220
221 if (start & 511)
222 return -EINVAL;
223 if (len & 511)
224 return -EINVAL;
225
226 if (start + len > i_size_read(bdev->bd_inode))
227 return -EINVAL;
228 truncate_inode_pages_range(mapping, start, start + len - 1);
229 return blkdev_issue_discard(bdev, start >> 9, len >> 9,
230 GFP_KERNEL, flags);
231}
232
233static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode,
234 unsigned long arg)
235{
236 uint64_t range[2];
237 struct address_space *mapping;
238 uint64_t start, end, len;
239
240 if (!(mode & FMODE_WRITE))
241 return -EBADF;
242
243 if (copy_from_user(range, (void __user *)arg, sizeof(range)))
244 return -EFAULT;
245
246 start = range[0];
247 len = range[1];
248 end = start + len - 1;
249
250 if (start & 511)
251 return -EINVAL;
252 if (len & 511)
253 return -EINVAL;
254 if (end >= (uint64_t)i_size_read(bdev->bd_inode))
255 return -EINVAL;
256 if (end < start)
257 return -EINVAL;
258
259 /* Invalidate the page cache, including dirty pages */
260 mapping = bdev->bd_inode->i_mapping;
261 truncate_inode_pages_range(mapping, start, end);
262
263 return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,
264 BLKDEV_ZERO_NOUNMAP);
265}
266
267static int put_ushort(unsigned long arg, unsigned short val)
268{
269 return put_user(val, (unsigned short __user *)arg);
270}
271
272static int put_int(unsigned long arg, int val)
273{
274 return put_user(val, (int __user *)arg);
275}
276
277static int put_uint(unsigned long arg, unsigned int val)
278{
279 return put_user(val, (unsigned int __user *)arg);
280}
281
282static int put_long(unsigned long arg, long val)
283{
284 return put_user(val, (long __user *)arg);
285}
286
287static int put_ulong(unsigned long arg, unsigned long val)
288{
289 return put_user(val, (unsigned long __user *)arg);
290}
291
292static int put_u64(unsigned long arg, u64 val)
293{
294 return put_user(val, (u64 __user *)arg);
295}
296
297int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
298 unsigned cmd, unsigned long arg)
299{
300 struct gendisk *disk = bdev->bd_disk;
301
302 if (disk->fops->ioctl)
303 return disk->fops->ioctl(bdev, mode, cmd, arg);
304
305 return -ENOTTY;
306}
307/*
308 * For the record: _GPL here is only because somebody decided to slap it
309 * on the previous export. Sheer idiocy, since it wasn't copyrightable
310 * at all and could be open-coded without any exports by anybody who cares.
311 */
312EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
313
314static int blkdev_pr_register(struct block_device *bdev,
315 struct pr_registration __user *arg)
316{
317 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
318 struct pr_registration reg;
319
320 if (!capable(CAP_SYS_ADMIN))
321 return -EPERM;
322 if (!ops || !ops->pr_register)
323 return -EOPNOTSUPP;
324 if (copy_from_user(&reg, arg, sizeof(reg)))
325 return -EFAULT;
326
327 if (reg.flags & ~PR_FL_IGNORE_KEY)
328 return -EOPNOTSUPP;
329 return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);
330}
331
332static int blkdev_pr_reserve(struct block_device *bdev,
333 struct pr_reservation __user *arg)
334{
335 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
336 struct pr_reservation rsv;
337
338 if (!capable(CAP_SYS_ADMIN))
339 return -EPERM;
340 if (!ops || !ops->pr_reserve)
341 return -EOPNOTSUPP;
342 if (copy_from_user(&rsv, arg, sizeof(rsv)))
343 return -EFAULT;
344
345 if (rsv.flags & ~PR_FL_IGNORE_KEY)
346 return -EOPNOTSUPP;
347 return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);
348}
349
350static int blkdev_pr_release(struct block_device *bdev,
351 struct pr_reservation __user *arg)
352{
353 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
354 struct pr_reservation rsv;
355
356 if (!capable(CAP_SYS_ADMIN))
357 return -EPERM;
358 if (!ops || !ops->pr_release)
359 return -EOPNOTSUPP;
360 if (copy_from_user(&rsv, arg, sizeof(rsv)))
361 return -EFAULT;
362
363 if (rsv.flags)
364 return -EOPNOTSUPP;
365 return ops->pr_release(bdev, rsv.key, rsv.type);
366}
367
368static int blkdev_pr_preempt(struct block_device *bdev,
369 struct pr_preempt __user *arg, bool abort)
370{
371 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
372 struct pr_preempt p;
373
374 if (!capable(CAP_SYS_ADMIN))
375 return -EPERM;
376 if (!ops || !ops->pr_preempt)
377 return -EOPNOTSUPP;
378 if (copy_from_user(&p, arg, sizeof(p)))
379 return -EFAULT;
380
381 if (p.flags)
382 return -EOPNOTSUPP;
383 return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);
384}
385
386static int blkdev_pr_clear(struct block_device *bdev,
387 struct pr_clear __user *arg)
388{
389 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
390 struct pr_clear c;
391
392 if (!capable(CAP_SYS_ADMIN))
393 return -EPERM;
394 if (!ops || !ops->pr_clear)
395 return -EOPNOTSUPP;
396 if (copy_from_user(&c, arg, sizeof(c)))
397 return -EFAULT;
398
399 if (c.flags)
400 return -EOPNOTSUPP;
401 return ops->pr_clear(bdev, c.key);
402}
403
404/*
405 * Is it an unrecognized ioctl? The correct returns are either
406 * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a
407 * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl
408 * code before returning.
409 *
410 * Confused drivers sometimes return EINVAL, which is wrong. It
411 * means "I understood the ioctl command, but the parameters to
412 * it were wrong".
413 *
414 * We should aim to just fix the broken drivers, the EINVAL case
415 * should go away.
416 */
417static inline int is_unrecognized_ioctl(int ret)
418{
419 return ret == -EINVAL ||
420 ret == -ENOTTY ||
421 ret == -ENOIOCTLCMD;
422}
423
424static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode,
425 unsigned cmd, unsigned long arg)
426{
427 int ret;
428
429 if (!capable(CAP_SYS_ADMIN))
430 return -EACCES;
431
432 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
433 if (!is_unrecognized_ioctl(ret))
434 return ret;
435
436 fsync_bdev(bdev);
437 invalidate_bdev(bdev);
438 return 0;
439}
440
441static int blkdev_roset(struct block_device *bdev, fmode_t mode,
442 unsigned cmd, unsigned long arg)
443{
444 int ret, n;
445
446 if (!capable(CAP_SYS_ADMIN))
447 return -EACCES;
448
449 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
450 if (!is_unrecognized_ioctl(ret))
451 return ret;
452 if (get_user(n, (int __user *)arg))
453 return -EFAULT;
454 set_device_ro(bdev, n);
455 return 0;
456}
457
458static 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/* set the logical block size */
485static int blkdev_bszset(struct block_device *bdev, fmode_t mode,
486 int __user *argp)
487{
488 int ret, n;
489
490 if (!capable(CAP_SYS_ADMIN))
491 return -EACCES;
492 if (!argp)
493 return -EINVAL;
494 if (get_user(n, argp))
495 return -EFAULT;
496
497 if (!(mode & FMODE_EXCL)) {
498 bdgrab(bdev);
499 if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0)
500 return -EBUSY;
501 }
502
503 ret = set_blocksize(bdev, n);
504 if (!(mode & FMODE_EXCL))
505 blkdev_put(bdev, mode | FMODE_EXCL);
506 return ret;
507}
508
509/*
510 * always keep this in sync with compat_blkdev_ioctl()
511 */
512int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
513 unsigned long arg)
514{
515 void __user *argp = (void __user *)arg;
516 loff_t size;
517 unsigned int max_sectors;
518
519 switch (cmd) {
520 case BLKFLSBUF:
521 return blkdev_flushbuf(bdev, mode, cmd, arg);
522 case BLKROSET:
523 return blkdev_roset(bdev, mode, cmd, arg);
524 case BLKDISCARD:
525 return blk_ioctl_discard(bdev, mode, arg, 0);
526 case BLKSECDISCARD:
527 return blk_ioctl_discard(bdev, mode, arg,
528 BLKDEV_DISCARD_SECURE);
529 case BLKZEROOUT:
530 return blk_ioctl_zeroout(bdev, mode, arg);
531 case BLKREPORTZONE:
532 return blkdev_report_zones_ioctl(bdev, mode, cmd, arg);
533 case BLKRESETZONE:
534 return blkdev_reset_zones_ioctl(bdev, mode, cmd, arg);
535 case BLKGETZONESZ:
536 return put_uint(arg, bdev_zone_sectors(bdev));
537 case BLKGETNRZONES:
538 return put_uint(arg, blkdev_nr_zones(bdev));
539 case HDIO_GETGEO:
540 return blkdev_getgeo(bdev, argp);
541 case BLKRAGET:
542 case BLKFRAGET:
543 if (!arg)
544 return -EINVAL;
545 return put_long(arg, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512);
546 case BLKROGET:
547 return put_int(arg, bdev_read_only(bdev) != 0);
548 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
549 return put_int(arg, block_size(bdev));
550 case BLKSSZGET: /* get block device logical block size */
551 return put_int(arg, bdev_logical_block_size(bdev));
552 case BLKPBSZGET: /* get block device physical block size */
553 return put_uint(arg, bdev_physical_block_size(bdev));
554 case BLKIOMIN:
555 return put_uint(arg, bdev_io_min(bdev));
556 case BLKIOOPT:
557 return put_uint(arg, bdev_io_opt(bdev));
558 case BLKALIGNOFF:
559 return put_int(arg, bdev_alignment_offset(bdev));
560 case BLKDISCARDZEROES:
561 return put_uint(arg, 0);
562 case BLKSECTGET:
563 max_sectors = min_t(unsigned int, USHRT_MAX,
564 queue_max_sectors(bdev_get_queue(bdev)));
565 return put_ushort(arg, max_sectors);
566 case BLKROTATIONAL:
567 return put_ushort(arg, !blk_queue_nonrot(bdev_get_queue(bdev)));
568 case BLKRASET:
569 case BLKFRASET:
570 if(!capable(CAP_SYS_ADMIN))
571 return -EACCES;
572 bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE;
573 return 0;
574 case BLKBSZSET:
575 return blkdev_bszset(bdev, mode, argp);
576 case BLKPG:
577 return blkpg_ioctl(bdev, argp);
578 case BLKRRPART:
579 return blkdev_reread_part(bdev);
580 case BLKGETSIZE:
581 size = i_size_read(bdev->bd_inode);
582 if ((size >> 9) > ~0UL)
583 return -EFBIG;
584 return put_ulong(arg, size >> 9);
585 case BLKGETSIZE64:
586 return put_u64(arg, i_size_read(bdev->bd_inode));
587 case BLKTRACESTART:
588 case BLKTRACESTOP:
589 case BLKTRACESETUP:
590 case BLKTRACETEARDOWN:
591 return blk_trace_ioctl(bdev, cmd, argp);
592 case IOC_PR_REGISTER:
593 return blkdev_pr_register(bdev, argp);
594 case IOC_PR_RESERVE:
595 return blkdev_pr_reserve(bdev, argp);
596 case IOC_PR_RELEASE:
597 return blkdev_pr_release(bdev, argp);
598 case IOC_PR_PREEMPT:
599 return blkdev_pr_preempt(bdev, argp, false);
600 case IOC_PR_PREEMPT_ABORT:
601 return blkdev_pr_preempt(bdev, argp, true);
602 case IOC_PR_CLEAR:
603 return blkdev_pr_clear(bdev, argp);
604 default:
605 return __blkdev_driver_ioctl(bdev, mode, cmd, arg);
606 }
607}
608EXPORT_SYMBOL_GPL(blkdev_ioctl);
609