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v5.4
  1// SPDX-License-Identifier: GPL-2.0
  2#include <linux/capability.h>
 
  3#include <linux/blkdev.h>
  4#include <linux/export.h>
  5#include <linux/gfp.h>
  6#include <linux/blkpg.h>
  7#include <linux/hdreg.h>
  8#include <linux/backing-dev.h>
  9#include <linux/fs.h>
 10#include <linux/blktrace_api.h>
 11#include <linux/pr.h>
 12#include <linux/uaccess.h>
 
 13
 14static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
 
 15{
 16	struct block_device *bdevp;
 17	struct gendisk *disk;
 18	struct hd_struct *part, *lpart;
 19	struct blkpg_ioctl_arg a;
 20	struct blkpg_partition p;
 21	struct disk_part_iter piter;
 22	long long start, length;
 23	int partno;
 24
 25	if (!capable(CAP_SYS_ADMIN))
 26		return -EACCES;
 27	if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
 28		return -EFAULT;
 29	if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
 30		return -EFAULT;
 31	disk = bdev->bd_disk;
 32	if (bdev != bdev->bd_contains)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 33		return -EINVAL;
 34	partno = p.pno;
 35	if (partno <= 0)
 36		return -EINVAL;
 37	switch (a.op) {
 38		case BLKPG_ADD_PARTITION:
 39			start = p.start >> 9;
 40			length = p.length >> 9;
 41			/* check for fit in a hd_struct */
 42			if (sizeof(sector_t) == sizeof(long) &&
 43			    sizeof(long long) > sizeof(long)) {
 44				long pstart = start, plength = length;
 45				if (pstart != start || plength != length
 46				    || pstart < 0 || plength < 0 || partno > 65535)
 47					return -EINVAL;
 48			}
 49			/* check if partition is aligned to blocksize */
 50			if (p.start & (bdev_logical_block_size(bdev) - 1))
 51				return -EINVAL;
 52
 53			mutex_lock(&bdev->bd_mutex);
 54
 55			/* overlap? */
 56			disk_part_iter_init(&piter, disk,
 57					    DISK_PITER_INCL_EMPTY);
 58			while ((part = disk_part_iter_next(&piter))) {
 59				if (!(start + length <= part->start_sect ||
 60				      start >= part->start_sect + part->nr_sects)) {
 61					disk_part_iter_exit(&piter);
 62					mutex_unlock(&bdev->bd_mutex);
 63					return -EBUSY;
 64				}
 65			}
 66			disk_part_iter_exit(&piter);
 67
 68			/* all seems OK */
 69			part = add_partition(disk, partno, start, length,
 70					     ADDPART_FLAG_NONE, NULL);
 71			mutex_unlock(&bdev->bd_mutex);
 72			return PTR_ERR_OR_ZERO(part);
 73		case BLKPG_DEL_PARTITION:
 74			part = disk_get_part(disk, partno);
 75			if (!part)
 76				return -ENXIO;
 77
 78			bdevp = bdget(part_devt(part));
 79			disk_put_part(part);
 80			if (!bdevp)
 81				return -ENOMEM;
 82
 83			mutex_lock(&bdevp->bd_mutex);
 84			if (bdevp->bd_openers) {
 85				mutex_unlock(&bdevp->bd_mutex);
 86				bdput(bdevp);
 87				return -EBUSY;
 88			}
 89			/* all seems OK */
 90			fsync_bdev(bdevp);
 91			invalidate_bdev(bdevp);
 92
 93			mutex_lock_nested(&bdev->bd_mutex, 1);
 94			delete_partition(disk, partno);
 95			mutex_unlock(&bdev->bd_mutex);
 96			mutex_unlock(&bdevp->bd_mutex);
 97			bdput(bdevp);
 98
 99			return 0;
100		case BLKPG_RESIZE_PARTITION:
101			start = p.start >> 9;
102			/* new length of partition in bytes */
103			length = p.length >> 9;
104			/* check for fit in a hd_struct */
105			if (sizeof(sector_t) == sizeof(long) &&
106			    sizeof(long long) > sizeof(long)) {
107				long pstart = start, plength = length;
108				if (pstart != start || plength != length
109				    || pstart < 0 || plength < 0)
110					return -EINVAL;
111			}
112			part = disk_get_part(disk, partno);
113			if (!part)
114				return -ENXIO;
115			bdevp = bdget(part_devt(part));
116			if (!bdevp) {
117				disk_put_part(part);
118				return -ENOMEM;
119			}
120			mutex_lock(&bdevp->bd_mutex);
121			mutex_lock_nested(&bdev->bd_mutex, 1);
122			if (start != part->start_sect) {
123				mutex_unlock(&bdevp->bd_mutex);
124				mutex_unlock(&bdev->bd_mutex);
125				bdput(bdevp);
126				disk_put_part(part);
127				return -EINVAL;
128			}
129			/* overlap? */
130			disk_part_iter_init(&piter, disk,
131					    DISK_PITER_INCL_EMPTY);
132			while ((lpart = disk_part_iter_next(&piter))) {
133				if (lpart->partno != partno &&
134				   !(start + length <= lpart->start_sect ||
135				   start >= lpart->start_sect + lpart->nr_sects)
136				   ) {
137					disk_part_iter_exit(&piter);
138					mutex_unlock(&bdevp->bd_mutex);
139					mutex_unlock(&bdev->bd_mutex);
140					bdput(bdevp);
141					disk_put_part(part);
142					return -EBUSY;
143				}
144			}
145			disk_part_iter_exit(&piter);
146			part_nr_sects_write(part, (sector_t)length);
147			i_size_write(bdevp->bd_inode, p.length);
148			mutex_unlock(&bdevp->bd_mutex);
149			mutex_unlock(&bdev->bd_mutex);
150			bdput(bdevp);
151			disk_put_part(part);
152			return 0;
153		default:
154			return -EINVAL;
155	}
156}
157
158/*
159 * This is an exported API for the block driver, and will not
160 * acquire bd_mutex. This API should be used in case that
161 * caller has held bd_mutex already.
162 */
163int __blkdev_reread_part(struct block_device *bdev)
164{
165	struct gendisk *disk = bdev->bd_disk;
166
167	if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains)
168		return -EINVAL;
169	if (!capable(CAP_SYS_ADMIN))
170		return -EACCES;
171
172	lockdep_assert_held(&bdev->bd_mutex);
 
173
174	return rescan_partitions(disk, bdev);
175}
176EXPORT_SYMBOL(__blkdev_reread_part);
177
178/*
179 * This is an exported API for the block driver, and will
180 * try to acquire bd_mutex. If bd_mutex has been held already
181 * in current context, please call __blkdev_reread_part().
182 *
183 * Make sure the held locks in current context aren't required
184 * in open()/close() handler and I/O path for avoiding ABBA deadlock:
185 * - bd_mutex is held before calling block driver's open/close
186 *   handler
187 * - reading partition table may submit I/O to the block device
188 */
189int blkdev_reread_part(struct block_device *bdev)
190{
191	int res;
 
192
193	mutex_lock(&bdev->bd_mutex);
194	res = __blkdev_reread_part(bdev);
195	mutex_unlock(&bdev->bd_mutex);
196
197	return res;
198}
199EXPORT_SYMBOL(blkdev_reread_part);
200
201static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode,
202		unsigned long arg, unsigned long flags)
203{
204	uint64_t range[2];
205	uint64_t start, len;
206	struct request_queue *q = bdev_get_queue(bdev);
207	struct address_space *mapping = bdev->bd_inode->i_mapping;
208
209
210	if (!(mode & FMODE_WRITE))
211		return -EBADF;
212
213	if (!blk_queue_discard(q))
214		return -EOPNOTSUPP;
215
216	if (copy_from_user(range, (void __user *)arg, sizeof(range)))
217		return -EFAULT;
218
219	start = range[0];
220	len = range[1];
221
222	if (start & 511)
223		return -EINVAL;
224	if (len & 511)
225		return -EINVAL;
226
227	if (start + len > i_size_read(bdev->bd_inode))
 
228		return -EINVAL;
229	truncate_inode_pages_range(mapping, start, start + len - 1);
230	return blkdev_issue_discard(bdev, start >> 9, len >> 9,
231				    GFP_KERNEL, flags);
 
 
 
 
 
 
232}
233
234static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
235		unsigned long arg)
236{
237	uint64_t range[2];
238	struct address_space *mapping;
239	uint64_t start, end, len;
 
 
240
241	if (!(mode & FMODE_WRITE))
242		return -EBADF;
243
244	if (copy_from_user(range, (void __user *)arg, sizeof(range)))
245		return -EFAULT;
246
247	start = range[0];
248	len = range[1];
249	end = start + len - 1;
250
251	if (start & 511)
252		return -EINVAL;
253	if (len & 511)
254		return -EINVAL;
255	if (end >= (uint64_t)i_size_read(bdev->bd_inode))
256		return -EINVAL;
257	if (end < start)
258		return -EINVAL;
259
260	/* Invalidate the page cache, including dirty pages */
261	mapping = bdev->bd_inode->i_mapping;
262	truncate_inode_pages_range(mapping, start, end);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
263
264	return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,
265			BLKDEV_ZERO_NOUNMAP);
 
266}
267
268static int put_ushort(unsigned long arg, unsigned short val)
269{
270	return put_user(val, (unsigned short __user *)arg);
271}
272
273static int put_int(unsigned long arg, int val)
274{
275	return put_user(val, (int __user *)arg);
276}
277
278static int put_uint(unsigned long arg, unsigned int val)
279{
280	return put_user(val, (unsigned int __user *)arg);
281}
282
283static int put_long(unsigned long arg, long val)
284{
285	return put_user(val, (long __user *)arg);
286}
287
288static int put_ulong(unsigned long arg, unsigned long val)
 
289{
290	return put_user(val, (unsigned long __user *)arg);
291}
292
293static int put_u64(unsigned long arg, u64 val)
294{
295	return put_user(val, (u64 __user *)arg);
296}
 
297
298int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
 
 
 
 
 
 
299			unsigned cmd, unsigned long arg)
300{
301	struct gendisk *disk = bdev->bd_disk;
302
303	if (disk->fops->ioctl)
304		return disk->fops->ioctl(bdev, mode, cmd, arg);
 
305
306	return -ENOTTY;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
307}
308/*
309 * For the record: _GPL here is only because somebody decided to slap it
310 * on the previous export.  Sheer idiocy, since it wasn't copyrightable
311 * at all and could be open-coded without any exports by anybody who cares.
312 */
313EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
314
315static int blkdev_pr_register(struct block_device *bdev,
316		struct pr_registration __user *arg)
317{
318	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
319	struct pr_registration reg;
320
321	if (!capable(CAP_SYS_ADMIN))
322		return -EPERM;
323	if (!ops || !ops->pr_register)
324		return -EOPNOTSUPP;
325	if (copy_from_user(&reg, arg, sizeof(reg)))
326		return -EFAULT;
327
328	if (reg.flags & ~PR_FL_IGNORE_KEY)
329		return -EOPNOTSUPP;
330	return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags);
331}
332
333static int blkdev_pr_reserve(struct block_device *bdev,
334		struct pr_reservation __user *arg)
335{
336	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
337	struct pr_reservation rsv;
338
339	if (!capable(CAP_SYS_ADMIN))
340		return -EPERM;
341	if (!ops || !ops->pr_reserve)
342		return -EOPNOTSUPP;
343	if (copy_from_user(&rsv, arg, sizeof(rsv)))
344		return -EFAULT;
345
346	if (rsv.flags & ~PR_FL_IGNORE_KEY)
347		return -EOPNOTSUPP;
348	return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags);
349}
350
351static int blkdev_pr_release(struct block_device *bdev,
352		struct pr_reservation __user *arg)
353{
354	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
355	struct pr_reservation rsv;
356
357	if (!capable(CAP_SYS_ADMIN))
358		return -EPERM;
359	if (!ops || !ops->pr_release)
360		return -EOPNOTSUPP;
361	if (copy_from_user(&rsv, arg, sizeof(rsv)))
362		return -EFAULT;
363
364	if (rsv.flags)
365		return -EOPNOTSUPP;
366	return ops->pr_release(bdev, rsv.key, rsv.type);
367}
368
369static int blkdev_pr_preempt(struct block_device *bdev,
370		struct pr_preempt __user *arg, bool abort)
371{
372	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
373	struct pr_preempt p;
374
375	if (!capable(CAP_SYS_ADMIN))
376		return -EPERM;
377	if (!ops || !ops->pr_preempt)
378		return -EOPNOTSUPP;
379	if (copy_from_user(&p, arg, sizeof(p)))
380		return -EFAULT;
381
382	if (p.flags)
383		return -EOPNOTSUPP;
384	return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort);
385}
386
387static int blkdev_pr_clear(struct block_device *bdev,
388		struct pr_clear __user *arg)
389{
390	const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops;
391	struct pr_clear c;
392
393	if (!capable(CAP_SYS_ADMIN))
394		return -EPERM;
395	if (!ops || !ops->pr_clear)
396		return -EOPNOTSUPP;
397	if (copy_from_user(&c, arg, sizeof(c)))
398		return -EFAULT;
399
400	if (c.flags)
401		return -EOPNOTSUPP;
402	return ops->pr_clear(bdev, c.key);
403}
404
405/*
406 * Is it an unrecognized ioctl? The correct returns are either
407 * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a
408 * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl
409 * code before returning.
410 *
411 * Confused drivers sometimes return EINVAL, which is wrong. It
412 * means "I understood the ioctl command, but the parameters to
413 * it were wrong".
414 *
415 * We should aim to just fix the broken drivers, the EINVAL case
416 * should go away.
417 */
418static inline int is_unrecognized_ioctl(int ret)
419{
420	return	ret == -EINVAL ||
421		ret == -ENOTTY ||
422		ret == -ENOIOCTLCMD;
423}
424
425static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode,
426		unsigned cmd, unsigned long arg)
427{
428	int ret;
429
430	if (!capable(CAP_SYS_ADMIN))
431		return -EACCES;
432
433	ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
434	if (!is_unrecognized_ioctl(ret))
435		return ret;
 
 
 
 
436
437	fsync_bdev(bdev);
438	invalidate_bdev(bdev);
439	return 0;
440}
441
442static int blkdev_roset(struct block_device *bdev, fmode_t mode,
443		unsigned cmd, unsigned long arg)
444{
445	int ret, n;
446
447	if (!capable(CAP_SYS_ADMIN))
448		return -EACCES;
449
450	ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
451	if (!is_unrecognized_ioctl(ret))
452		return ret;
453	if (get_user(n, (int __user *)arg))
454		return -EFAULT;
455	set_device_ro(bdev, n);
 
 
 
 
 
456	return 0;
457}
458
459static int blkdev_getgeo(struct block_device *bdev,
460		struct hd_geometry __user *argp)
461{
462	struct gendisk *disk = bdev->bd_disk;
463	struct hd_geometry geo;
464	int ret;
465
466	if (!argp)
467		return -EINVAL;
468	if (!disk->fops->getgeo)
469		return -ENOTTY;
470
471	/*
472	 * We need to set the startsect first, the driver may
473	 * want to override it.
474	 */
475	memset(&geo, 0, sizeof(geo));
476	geo.start = get_start_sect(bdev);
477	ret = disk->fops->getgeo(bdev, &geo);
478	if (ret)
479		return ret;
480	if (copy_to_user(argp, &geo, sizeof(geo)))
481		return -EFAULT;
482	return 0;
483}
484
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
485/* set the logical block size */
486static int blkdev_bszset(struct block_device *bdev, fmode_t mode,
487		int __user *argp)
488{
489	int ret, n;
 
490
491	if (!capable(CAP_SYS_ADMIN))
492		return -EACCES;
493	if (!argp)
494		return -EINVAL;
495	if (get_user(n, argp))
496		return -EFAULT;
497
498	if (!(mode & FMODE_EXCL)) {
499		bdgrab(bdev);
500		if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0)
501			return -EBUSY;
502	}
503
 
 
 
504	ret = set_blocksize(bdev, n);
505	if (!(mode & FMODE_EXCL))
506		blkdev_put(bdev, mode | FMODE_EXCL);
507	return ret;
508}
509
510/*
511 * always keep this in sync with compat_blkdev_ioctl()
 
 
512 */
513int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
514			unsigned long arg)
 
515{
516	void __user *argp = (void __user *)arg;
517	loff_t size;
518	unsigned int max_sectors;
519
520	switch (cmd) {
521	case BLKFLSBUF:
522		return blkdev_flushbuf(bdev, mode, cmd, arg);
523	case BLKROSET:
524		return blkdev_roset(bdev, mode, cmd, arg);
525	case BLKDISCARD:
526		return blk_ioctl_discard(bdev, mode, arg, 0);
527	case BLKSECDISCARD:
528		return blk_ioctl_discard(bdev, mode, arg,
529				BLKDEV_DISCARD_SECURE);
530	case BLKZEROOUT:
531		return blk_ioctl_zeroout(bdev, mode, arg);
 
 
532	case BLKREPORTZONE:
533		return blkdev_report_zones_ioctl(bdev, mode, cmd, arg);
534	case BLKRESETZONE:
535		return blkdev_reset_zones_ioctl(bdev, mode, cmd, arg);
 
 
 
536	case BLKGETZONESZ:
537		return put_uint(arg, bdev_zone_sectors(bdev));
538	case BLKGETNRZONES:
539		return put_uint(arg, blkdev_nr_zones(bdev));
540	case HDIO_GETGEO:
541		return blkdev_getgeo(bdev, argp);
542	case BLKRAGET:
543	case BLKFRAGET:
544		if (!arg)
545			return -EINVAL;
546		return put_long(arg, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512);
547	case BLKROGET:
548		return put_int(arg, bdev_read_only(bdev) != 0);
549	case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
550		return put_int(arg, block_size(bdev));
551	case BLKSSZGET: /* get block device logical block size */
552		return put_int(arg, bdev_logical_block_size(bdev));
553	case BLKPBSZGET: /* get block device physical block size */
554		return put_uint(arg, bdev_physical_block_size(bdev));
555	case BLKIOMIN:
556		return put_uint(arg, bdev_io_min(bdev));
557	case BLKIOOPT:
558		return put_uint(arg, bdev_io_opt(bdev));
559	case BLKALIGNOFF:
560		return put_int(arg, bdev_alignment_offset(bdev));
561	case BLKDISCARDZEROES:
562		return put_uint(arg, 0);
563	case BLKSECTGET:
564		max_sectors = min_t(unsigned int, USHRT_MAX,
565				    queue_max_sectors(bdev_get_queue(bdev)));
566		return put_ushort(arg, max_sectors);
567	case BLKROTATIONAL:
568		return put_ushort(arg, !blk_queue_nonrot(bdev_get_queue(bdev)));
569	case BLKRASET:
570	case BLKFRASET:
571		if(!capable(CAP_SYS_ADMIN))
572			return -EACCES;
573		bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE;
574		return 0;
575	case BLKBSZSET:
576		return blkdev_bszset(bdev, mode, argp);
577	case BLKPG:
578		return blkpg_ioctl(bdev, argp);
579	case BLKRRPART:
580		return blkdev_reread_part(bdev);
581	case BLKGETSIZE:
582		size = i_size_read(bdev->bd_inode);
583		if ((size >> 9) > ~0UL)
584			return -EFBIG;
585		return put_ulong(arg, size >> 9);
586	case BLKGETSIZE64:
587		return put_u64(arg, i_size_read(bdev->bd_inode));
588	case BLKTRACESTART:
589	case BLKTRACESTOP:
590	case BLKTRACESETUP:
591	case BLKTRACETEARDOWN:
592		return blk_trace_ioctl(bdev, cmd, argp);
593	case IOC_PR_REGISTER:
594		return blkdev_pr_register(bdev, argp);
595	case IOC_PR_RESERVE:
596		return blkdev_pr_reserve(bdev, argp);
597	case IOC_PR_RELEASE:
598		return blkdev_pr_release(bdev, argp);
599	case IOC_PR_PREEMPT:
600		return blkdev_pr_preempt(bdev, argp, false);
601	case IOC_PR_PREEMPT_ABORT:
602		return blkdev_pr_preempt(bdev, argp, true);
603	case IOC_PR_CLEAR:
604		return blkdev_pr_clear(bdev, argp);
605	default:
606		return __blkdev_driver_ioctl(bdev, mode, cmd, arg);
607	}
608}
609EXPORT_SYMBOL_GPL(blkdev_ioctl);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
v6.9.4
  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(&p, upart, 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, 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, p.pno, start, length);
 55	case BLKPG_RESIZE_PARTITION:
 56		return bdev_resize_partition(disk, 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, 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, compat_ptr(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(range, (void __user *)arg, 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(inode->i_mapping);
125	err = truncate_bdev_range(bdev, mode, start, start + len - 1);
126	if (err)
127		goto fail;
128	err = blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL);
129fail:
130	filemap_invalidate_unlock(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(range, argp, 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(bdev->bd_inode->i_mapping);
156	err = truncate_bdev_range(bdev, mode, start, start + len - 1);
157	if (!err)
158		err = blkdev_issue_secure_erase(bdev, start >> 9, len >> 9,
159						GFP_KERNEL);
160	filemap_invalidate_unlock(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(range, (void __user *)arg, 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(inode->i_mapping);
194	err = truncate_bdev_range(bdev, mode, start, end);
195	if (err)
196		goto fail;
197
198	err = blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL,
199				   BLKDEV_ZERO_NOUNMAP);
200
201fail:
202	filemap_invalidate_unlock(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(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(&reg, arg, 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(&rsv, arg, 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(&rsv, arg, 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(&p, arg, 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(&c, arg, 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(&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(argp, &geo, 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(ugeo, &geo, 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, n);
 
 
 
491
492	file = bdev_file_open_by_dev(bdev->bd_dev, mode, &bdev, NULL);
493	if (IS_ERR(file))
494		return -EBUSY;
495	ret = set_blocksize(bdev, 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, 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, bdev_zone_sectors(bdev));
533	case BLKGETNRZONES:
534		return put_uint(argp, bdev_nr_zones(bdev));
 
 
 
 
 
 
 
535	case BLKROGET:
536		return put_int(argp, bdev_read_only(bdev) != 0);
 
 
537	case BLKSSZGET: /* get block device logical block size */
538		return put_int(argp, bdev_logical_block_size(bdev));
539	case BLKPBSZGET: /* get block device physical block size */
540		return put_uint(argp, bdev_physical_block_size(bdev));
541	case BLKIOMIN:
542		return put_uint(argp, bdev_io_min(bdev));
543	case BLKIOOPT:
544		return put_uint(argp, bdev_io_opt(bdev));
545	case BLKALIGNOFF:
546		return put_int(argp, bdev_alignment_offset(bdev));
547	case BLKDISCARDZEROES:
548		return put_uint(argp, 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, max_sectors);
553	case BLKROTATIONAL:
554		return put_ushort(argp, !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(bdev->bd_disk,
567				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, argp);
574	case IOC_PR_RESERVE:
575		return blkdev_pr_reserve(bdev, mode, argp);
576	case IOC_PR_RELEASE:
577		return blkdev_pr_release(bdev, mode, argp);
578	case IOC_PR_PREEMPT:
579		return blkdev_pr_preempt(bdev, mode, argp, false);
580	case IOC_PR_PREEMPT_ABORT:
581		return blkdev_pr_preempt(bdev, mode, argp, true);
582	case IOC_PR_CLEAR:
583		return blkdev_pr_clear(bdev, mode, 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(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, 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			(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, 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, block_size(bdev));
624	case BLKBSZSET:
625		return blkdev_bszset(bdev, mode, argp);
626	case BLKGETSIZE64:
627		return put_u64(argp, 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(arg);
658	struct block_device *bdev = I_BDEV(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, argp);
666	case BLKPG:
667		return compat_blkpg_ioctl(bdev, 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			(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, 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, 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, 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