drivers/rtc/rtc-da9052.c: add constraints to set valid year
[linux-2.6-block.git] / block / ioctl.c
CommitLineData
c59ede7b 1#include <linux/capability.h>
1da177e4 2#include <linux/blkdev.h>
d5decd3b 3#include <linux/export.h>
5a0e3ad6 4#include <linux/gfp.h>
1da177e4 5#include <linux/blkpg.h>
a885c8c4 6#include <linux/hdreg.h>
1da177e4 7#include <linux/backing-dev.h>
ff01bb48 8#include <linux/fs.h>
2056a782 9#include <linux/blktrace_api.h>
1da177e4
LT
10#include <asm/uaccess.h>
11
12static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
13{
14 struct block_device *bdevp;
15 struct gendisk *disk;
c83f6bf9 16 struct hd_struct *part, *lpart;
1da177e4
LT
17 struct blkpg_ioctl_arg a;
18 struct blkpg_partition p;
e71bf0d0 19 struct disk_part_iter piter;
1da177e4 20 long long start, length;
cf771cb5 21 int partno;
1da177e4
LT
22
23 if (!capable(CAP_SYS_ADMIN))
24 return -EACCES;
25 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
26 return -EFAULT;
27 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
28 return -EFAULT;
29 disk = bdev->bd_disk;
30 if (bdev != bdev->bd_contains)
31 return -EINVAL;
cf771cb5 32 partno = p.pno;
540eed56 33 if (partno <= 0)
1da177e4
LT
34 return -EINVAL;
35 switch (a.op) {
36 case BLKPG_ADD_PARTITION:
37 start = p.start >> 9;
38 length = p.length >> 9;
c83f6bf9
VG
39 /* check for fit in a hd_struct */
40 if (sizeof(sector_t) == sizeof(long) &&
1da177e4
LT
41 sizeof(long long) > sizeof(long)) {
42 long pstart = start, plength = length;
43 if (pstart != start || plength != length
2bd6efad 44 || pstart < 0 || plength < 0 || partno > 65535)
1da177e4
LT
45 return -EINVAL;
46 }
88e34126 47
c039e313 48 mutex_lock(&bdev->bd_mutex);
88e34126 49
1da177e4 50 /* overlap? */
e71bf0d0
TH
51 disk_part_iter_init(&piter, disk,
52 DISK_PITER_INCL_EMPTY);
53 while ((part = disk_part_iter_next(&piter))) {
54 if (!(start + length <= part->start_sect ||
55 start >= part->start_sect + part->nr_sects)) {
56 disk_part_iter_exit(&piter);
c039e313 57 mutex_unlock(&bdev->bd_mutex);
1da177e4
LT
58 return -EBUSY;
59 }
60 }
e71bf0d0
TH
61 disk_part_iter_exit(&piter);
62
1da177e4 63 /* all seems OK */
ba32929a 64 part = add_partition(disk, partno, start, length,
6d1d8050 65 ADDPART_FLAG_NONE, NULL);
c039e313 66 mutex_unlock(&bdev->bd_mutex);
c7d1ba41 67 return PTR_ERR_OR_ZERO(part);
1da177e4 68 case BLKPG_DEL_PARTITION:
e71bf0d0
TH
69 part = disk_get_part(disk, partno);
70 if (!part)
1da177e4 71 return -ENXIO;
e71bf0d0
TH
72
73 bdevp = bdget(part_devt(part));
74 disk_put_part(part);
1da177e4
LT
75 if (!bdevp)
76 return -ENOMEM;
e71bf0d0 77
2e7b651d 78 mutex_lock(&bdevp->bd_mutex);
1da177e4 79 if (bdevp->bd_openers) {
c039e313 80 mutex_unlock(&bdevp->bd_mutex);
1da177e4
LT
81 bdput(bdevp);
82 return -EBUSY;
83 }
84 /* all seems OK */
85 fsync_bdev(bdevp);
f98393a6 86 invalidate_bdev(bdevp);
1da177e4 87
6d740cd5 88 mutex_lock_nested(&bdev->bd_mutex, 1);
cf771cb5 89 delete_partition(disk, partno);
c039e313
AV
90 mutex_unlock(&bdev->bd_mutex);
91 mutex_unlock(&bdevp->bd_mutex);
1da177e4
LT
92 bdput(bdevp);
93
c83f6bf9
VG
94 return 0;
95 case BLKPG_RESIZE_PARTITION:
96 start = p.start >> 9;
97 /* new length of partition in bytes */
98 length = p.length >> 9;
99 /* check for fit in a hd_struct */
100 if (sizeof(sector_t) == sizeof(long) &&
101 sizeof(long long) > sizeof(long)) {
102 long pstart = start, plength = length;
103 if (pstart != start || plength != length
104 || pstart < 0 || plength < 0)
105 return -EINVAL;
106 }
107 part = disk_get_part(disk, partno);
108 if (!part)
109 return -ENXIO;
110 bdevp = bdget(part_devt(part));
111 if (!bdevp) {
112 disk_put_part(part);
113 return -ENOMEM;
114 }
115 mutex_lock(&bdevp->bd_mutex);
116 mutex_lock_nested(&bdev->bd_mutex, 1);
117 if (start != part->start_sect) {
118 mutex_unlock(&bdevp->bd_mutex);
119 mutex_unlock(&bdev->bd_mutex);
120 bdput(bdevp);
121 disk_put_part(part);
122 return -EINVAL;
123 }
124 /* overlap? */
125 disk_part_iter_init(&piter, disk,
126 DISK_PITER_INCL_EMPTY);
127 while ((lpart = disk_part_iter_next(&piter))) {
128 if (lpart->partno != partno &&
129 !(start + length <= lpart->start_sect ||
130 start >= lpart->start_sect + lpart->nr_sects)
131 ) {
132 disk_part_iter_exit(&piter);
133 mutex_unlock(&bdevp->bd_mutex);
134 mutex_unlock(&bdev->bd_mutex);
135 bdput(bdevp);
136 disk_put_part(part);
137 return -EBUSY;
138 }
139 }
140 disk_part_iter_exit(&piter);
141 part_nr_sects_write(part, (sector_t)length);
142 i_size_write(bdevp->bd_inode, p.length);
143 mutex_unlock(&bdevp->bd_mutex);
144 mutex_unlock(&bdev->bd_mutex);
145 bdput(bdevp);
146 disk_put_part(part);
1da177e4
LT
147 return 0;
148 default:
149 return -EINVAL;
150 }
151}
152
153static int blkdev_reread_part(struct block_device *bdev)
154{
155 struct gendisk *disk = bdev->bd_disk;
156 int res;
157
d27769ec 158 if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains)
1da177e4
LT
159 return -EINVAL;
160 if (!capable(CAP_SYS_ADMIN))
161 return -EACCES;
c039e313 162 if (!mutex_trylock(&bdev->bd_mutex))
1da177e4
LT
163 return -EBUSY;
164 res = rescan_partitions(disk, bdev);
c039e313 165 mutex_unlock(&bdev->bd_mutex);
1da177e4
LT
166 return res;
167}
168
d30a2605 169static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
8d57a98c 170 uint64_t len, int secure)
d30a2605 171{
dd3932ed 172 unsigned long flags = 0;
8d57a98c 173
d30a2605
DW
174 if (start & 511)
175 return -EINVAL;
176 if (len & 511)
177 return -EINVAL;
178 start >>= 9;
179 len >>= 9;
180
77304d2a 181 if (start + len > (i_size_read(bdev->bd_inode) >> 9))
d30a2605 182 return -EINVAL;
8d57a98c 183 if (secure)
dd3932ed 184 flags |= BLKDEV_DISCARD_SECURE;
8d57a98c 185 return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, flags);
d30a2605
DW
186}
187
66ba32dc
MP
188static int blk_ioctl_zeroout(struct block_device *bdev, uint64_t start,
189 uint64_t len)
190{
191 if (start & 511)
192 return -EINVAL;
193 if (len & 511)
194 return -EINVAL;
195 start >>= 9;
196 len >>= 9;
197
198 if (start + len > (i_size_read(bdev->bd_inode) >> 9))
199 return -EINVAL;
200
d93ba7a5 201 return blkdev_issue_zeroout(bdev, start, len, GFP_KERNEL, false);
66ba32dc
MP
202}
203
1da177e4
LT
204static int put_ushort(unsigned long arg, unsigned short val)
205{
206 return put_user(val, (unsigned short __user *)arg);
207}
208
209static int put_int(unsigned long arg, int val)
210{
211 return put_user(val, (int __user *)arg);
212}
213
ac481c20
MP
214static int put_uint(unsigned long arg, unsigned int val)
215{
216 return put_user(val, (unsigned int __user *)arg);
217}
218
1da177e4
LT
219static int put_long(unsigned long arg, long val)
220{
221 return put_user(val, (long __user *)arg);
222}
223
224static int put_ulong(unsigned long arg, unsigned long val)
225{
226 return put_user(val, (unsigned long __user *)arg);
227}
228
229static int put_u64(unsigned long arg, u64 val)
230{
231 return put_user(val, (u64 __user *)arg);
232}
233
633a08b8
AV
234int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
235 unsigned cmd, unsigned long arg)
236{
237 struct gendisk *disk = bdev->bd_disk;
d4430d62
AV
238
239 if (disk->fops->ioctl)
240 return disk->fops->ioctl(bdev, mode, cmd, arg);
633a08b8 241
633a08b8
AV
242 return -ENOTTY;
243}
244/*
245 * For the record: _GPL here is only because somebody decided to slap it
246 * on the previous export. Sheer idiocy, since it wasn't copyrightable
247 * at all and could be open-coded without any exports by anybody who cares.
248 */
249EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
250
07d106d0
LT
251/*
252 * Is it an unrecognized ioctl? The correct returns are either
253 * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a
254 * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl
255 * code before returning.
256 *
257 * Confused drivers sometimes return EINVAL, which is wrong. It
258 * means "I understood the ioctl command, but the parameters to
259 * it were wrong".
260 *
261 * We should aim to just fix the broken drivers, the EINVAL case
262 * should go away.
263 */
264static inline int is_unrecognized_ioctl(int ret)
265{
266 return ret == -EINVAL ||
267 ret == -ENOTTY ||
268 ret == -ENOIOCTLCMD;
269}
270
f58c4c0a 271/*
8a6cfeb6 272 * always keep this in sync with compat_blkdev_ioctl()
f58c4c0a 273 */
56b26add 274int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
bb93e3a5
AB
275 unsigned long arg)
276{
bb93e3a5 277 struct gendisk *disk = bdev->bd_disk;
45048d09
AV
278 struct backing_dev_info *bdi;
279 loff_t size;
bb93e3a5 280 int ret, n;
63f26496 281 unsigned int max_sectors;
bb93e3a5
AB
282
283 switch(cmd) {
1da177e4
LT
284 case BLKFLSBUF:
285 if (!capable(CAP_SYS_ADMIN))
286 return -EACCES;
bb93e3a5 287
e436fdae 288 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
07d106d0 289 if (!is_unrecognized_ioctl(ret))
bb93e3a5
AB
290 return ret;
291
1da177e4 292 fsync_bdev(bdev);
f98393a6 293 invalidate_bdev(bdev);
1da177e4 294 return 0;
bb93e3a5 295
1da177e4 296 case BLKROSET:
e436fdae 297 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
07d106d0 298 if (!is_unrecognized_ioctl(ret))
bb93e3a5 299 return ret;
1da177e4
LT
300 if (!capable(CAP_SYS_ADMIN))
301 return -EACCES;
302 if (get_user(n, (int __user *)(arg)))
303 return -EFAULT;
304 set_device_ro(bdev, n);
305 return 0;
d30a2605 306
8d57a98c
AH
307 case BLKDISCARD:
308 case BLKSECDISCARD: {
d30a2605
DW
309 uint64_t range[2];
310
e436fdae 311 if (!(mode & FMODE_WRITE))
d30a2605
DW
312 return -EBADF;
313
314 if (copy_from_user(range, (void __user *)arg, sizeof(range)))
315 return -EFAULT;
316
8d57a98c
AH
317 return blk_ioctl_discard(bdev, range[0], range[1],
318 cmd == BLKSECDISCARD);
d30a2605 319 }
66ba32dc
MP
320 case BLKZEROOUT: {
321 uint64_t range[2];
322
323 if (!(mode & FMODE_WRITE))
324 return -EBADF;
325
326 if (copy_from_user(range, (void __user *)arg, sizeof(range)))
327 return -EFAULT;
328
329 return blk_ioctl_zeroout(bdev, range[0], range[1]);
330 }
d30a2605 331
a885c8c4
CH
332 case HDIO_GETGEO: {
333 struct hd_geometry geo;
334
335 if (!arg)
336 return -EINVAL;
337 if (!disk->fops->getgeo)
338 return -ENOTTY;
339
340 /*
341 * We need to set the startsect first, the driver may
342 * want to override it.
343 */
a014741c 344 memset(&geo, 0, sizeof(geo));
a885c8c4
CH
345 geo.start = get_start_sect(bdev);
346 ret = disk->fops->getgeo(bdev, &geo);
347 if (ret)
348 return ret;
349 if (copy_to_user((struct hd_geometry __user *)arg, &geo,
350 sizeof(geo)))
351 return -EFAULT;
352 return 0;
353 }
45048d09
AV
354 case BLKRAGET:
355 case BLKFRAGET:
356 if (!arg)
357 return -EINVAL;
358 bdi = blk_get_backing_dev_info(bdev);
45048d09
AV
359 return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
360 case BLKROGET:
361 return put_int(arg, bdev_read_only(bdev) != 0);
ac481c20 362 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
45048d09 363 return put_int(arg, block_size(bdev));
ac481c20 364 case BLKSSZGET: /* get block device logical block size */
e1defc4f 365 return put_int(arg, bdev_logical_block_size(bdev));
ac481c20
MP
366 case BLKPBSZGET: /* get block device physical block size */
367 return put_uint(arg, bdev_physical_block_size(bdev));
368 case BLKIOMIN:
369 return put_uint(arg, bdev_io_min(bdev));
370 case BLKIOOPT:
371 return put_uint(arg, bdev_io_opt(bdev));
372 case BLKALIGNOFF:
373 return put_int(arg, bdev_alignment_offset(bdev));
98262f27
MP
374 case BLKDISCARDZEROES:
375 return put_uint(arg, bdev_discard_zeroes_data(bdev));
45048d09 376 case BLKSECTGET:
63f26496
AM
377 max_sectors = min_t(unsigned int, USHRT_MAX,
378 queue_max_sectors(bdev_get_queue(bdev)));
379 return put_ushort(arg, max_sectors);
ef00f59c
MP
380 case BLKROTATIONAL:
381 return put_ushort(arg, !blk_queue_nonrot(bdev_get_queue(bdev)));
45048d09
AV
382 case BLKRASET:
383 case BLKFRASET:
384 if(!capable(CAP_SYS_ADMIN))
385 return -EACCES;
386 bdi = blk_get_backing_dev_info(bdev);
45048d09 387 bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
45048d09
AV
388 return 0;
389 case BLKBSZSET:
390 /* set the logical block size */
391 if (!capable(CAP_SYS_ADMIN))
392 return -EACCES;
393 if (!arg)
394 return -EINVAL;
395 if (get_user(n, (int __user *) arg))
396 return -EFAULT;
3c522ced
MS
397 if (!(mode & FMODE_EXCL)) {
398 bdgrab(bdev);
399 if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0)
400 return -EBUSY;
401 }
45048d09 402 ret = set_blocksize(bdev, n);
6af3a56e 403 if (!(mode & FMODE_EXCL))
e525fd89 404 blkdev_put(bdev, mode | FMODE_EXCL);
bb93e3a5 405 return ret;
45048d09 406 case BLKPG:
45048d09 407 ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
45048d09
AV
408 break;
409 case BLKRRPART:
45048d09 410 ret = blkdev_reread_part(bdev);
45048d09
AV
411 break;
412 case BLKGETSIZE:
77304d2a 413 size = i_size_read(bdev->bd_inode);
45048d09
AV
414 if ((size >> 9) > ~0UL)
415 return -EFBIG;
416 return put_ulong(arg, size >> 9);
417 case BLKGETSIZE64:
77304d2a 418 return put_u64(arg, i_size_read(bdev->bd_inode));
45048d09
AV
419 case BLKTRACESTART:
420 case BLKTRACESTOP:
421 case BLKTRACESETUP:
422 case BLKTRACETEARDOWN:
45048d09 423 ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg);
45048d09
AV
424 break;
425 default:
426 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
427 }
428 return ret;
1da177e4 429}
68f66feb 430EXPORT_SYMBOL_GPL(blkdev_ioctl);