Merge branch 'for-linus' of git://git.infradead.org/users/sameo/mfd-2.6
[linux-btrfs-devel.git] / block / ioctl.c
blob1124cd297263571d63371ca8ed33f8c361b74e06
1 #include <linux/capability.h>
2 #include <linux/blkdev.h>
3 #include <linux/gfp.h>
4 #include <linux/blkpg.h>
5 #include <linux/hdreg.h>
6 #include <linux/backing-dev.h>
7 #include <linux/buffer_head.h>
8 #include <linux/blktrace_api.h>
9 #include <asm/uaccess.h>
11 static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
13 struct block_device *bdevp;
14 struct gendisk *disk;
15 struct hd_struct *part;
16 struct blkpg_ioctl_arg a;
17 struct blkpg_partition p;
18 struct disk_part_iter piter;
19 long long start, length;
20 int partno;
22 if (!capable(CAP_SYS_ADMIN))
23 return -EACCES;
24 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
25 return -EFAULT;
26 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
27 return -EFAULT;
28 disk = bdev->bd_disk;
29 if (bdev != bdev->bd_contains)
30 return -EINVAL;
31 partno = p.pno;
32 if (partno <= 0)
33 return -EINVAL;
34 switch (a.op) {
35 case BLKPG_ADD_PARTITION:
36 start = p.start >> 9;
37 length = p.length >> 9;
38 /* check for fit in a hd_struct */
39 if (sizeof(sector_t) == sizeof(long) &&
40 sizeof(long long) > sizeof(long)) {
41 long pstart = start, plength = length;
42 if (pstart != start || plength != length
43 || pstart < 0 || plength < 0)
44 return -EINVAL;
47 mutex_lock(&bdev->bd_mutex);
49 /* overlap? */
50 disk_part_iter_init(&piter, disk,
51 DISK_PITER_INCL_EMPTY);
52 while ((part = disk_part_iter_next(&piter))) {
53 if (!(start + length <= part->start_sect ||
54 start >= part->start_sect + part->nr_sects)) {
55 disk_part_iter_exit(&piter);
56 mutex_unlock(&bdev->bd_mutex);
57 return -EBUSY;
60 disk_part_iter_exit(&piter);
62 /* all seems OK */
63 part = add_partition(disk, partno, start, length,
64 ADDPART_FLAG_NONE, NULL);
65 mutex_unlock(&bdev->bd_mutex);
66 return IS_ERR(part) ? PTR_ERR(part) : 0;
67 case BLKPG_DEL_PARTITION:
68 part = disk_get_part(disk, partno);
69 if (!part)
70 return -ENXIO;
72 bdevp = bdget(part_devt(part));
73 disk_put_part(part);
74 if (!bdevp)
75 return -ENOMEM;
77 mutex_lock(&bdevp->bd_mutex);
78 if (bdevp->bd_openers) {
79 mutex_unlock(&bdevp->bd_mutex);
80 bdput(bdevp);
81 return -EBUSY;
83 /* all seems OK */
84 fsync_bdev(bdevp);
85 invalidate_bdev(bdevp);
87 mutex_lock_nested(&bdev->bd_mutex, 1);
88 delete_partition(disk, partno);
89 mutex_unlock(&bdev->bd_mutex);
90 mutex_unlock(&bdevp->bd_mutex);
91 bdput(bdevp);
93 return 0;
94 default:
95 return -EINVAL;
99 static int blkdev_reread_part(struct block_device *bdev)
101 struct gendisk *disk = bdev->bd_disk;
102 int res;
104 if (!disk_partitionable(disk) || bdev != bdev->bd_contains)
105 return -EINVAL;
106 if (!capable(CAP_SYS_ADMIN))
107 return -EACCES;
108 if (!mutex_trylock(&bdev->bd_mutex))
109 return -EBUSY;
110 res = rescan_partitions(disk, bdev);
111 mutex_unlock(&bdev->bd_mutex);
112 return res;
115 static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
116 uint64_t len, int secure)
118 unsigned long flags = 0;
120 if (start & 511)
121 return -EINVAL;
122 if (len & 511)
123 return -EINVAL;
124 start >>= 9;
125 len >>= 9;
127 if (start + len > (i_size_read(bdev->bd_inode) >> 9))
128 return -EINVAL;
129 if (secure)
130 flags |= BLKDEV_DISCARD_SECURE;
131 return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, flags);
134 static int put_ushort(unsigned long arg, unsigned short val)
136 return put_user(val, (unsigned short __user *)arg);
139 static int put_int(unsigned long arg, int val)
141 return put_user(val, (int __user *)arg);
144 static int put_uint(unsigned long arg, unsigned int val)
146 return put_user(val, (unsigned int __user *)arg);
149 static int put_long(unsigned long arg, long val)
151 return put_user(val, (long __user *)arg);
154 static int put_ulong(unsigned long arg, unsigned long val)
156 return put_user(val, (unsigned long __user *)arg);
159 static int put_u64(unsigned long arg, u64 val)
161 return put_user(val, (u64 __user *)arg);
164 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
165 unsigned cmd, unsigned long arg)
167 struct gendisk *disk = bdev->bd_disk;
169 if (disk->fops->ioctl)
170 return disk->fops->ioctl(bdev, mode, cmd, arg);
172 return -ENOTTY;
175 * For the record: _GPL here is only because somebody decided to slap it
176 * on the previous export. Sheer idiocy, since it wasn't copyrightable
177 * at all and could be open-coded without any exports by anybody who cares.
179 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
182 * always keep this in sync with compat_blkdev_ioctl()
184 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
185 unsigned long arg)
187 struct gendisk *disk = bdev->bd_disk;
188 struct backing_dev_info *bdi;
189 loff_t size;
190 int ret, n;
192 switch(cmd) {
193 case BLKFLSBUF:
194 if (!capable(CAP_SYS_ADMIN))
195 return -EACCES;
197 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
198 /* -EINVAL to handle old uncorrected drivers */
199 if (ret != -EINVAL && ret != -ENOTTY)
200 return ret;
202 fsync_bdev(bdev);
203 invalidate_bdev(bdev);
204 return 0;
206 case BLKROSET:
207 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
208 /* -EINVAL to handle old uncorrected drivers */
209 if (ret != -EINVAL && ret != -ENOTTY)
210 return ret;
211 if (!capable(CAP_SYS_ADMIN))
212 return -EACCES;
213 if (get_user(n, (int __user *)(arg)))
214 return -EFAULT;
215 set_device_ro(bdev, n);
216 return 0;
218 case BLKDISCARD:
219 case BLKSECDISCARD: {
220 uint64_t range[2];
222 if (!(mode & FMODE_WRITE))
223 return -EBADF;
225 if (copy_from_user(range, (void __user *)arg, sizeof(range)))
226 return -EFAULT;
228 return blk_ioctl_discard(bdev, range[0], range[1],
229 cmd == BLKSECDISCARD);
232 case HDIO_GETGEO: {
233 struct hd_geometry geo;
235 if (!arg)
236 return -EINVAL;
237 if (!disk->fops->getgeo)
238 return -ENOTTY;
241 * We need to set the startsect first, the driver may
242 * want to override it.
244 memset(&geo, 0, sizeof(geo));
245 geo.start = get_start_sect(bdev);
246 ret = disk->fops->getgeo(bdev, &geo);
247 if (ret)
248 return ret;
249 if (copy_to_user((struct hd_geometry __user *)arg, &geo,
250 sizeof(geo)))
251 return -EFAULT;
252 return 0;
254 case BLKRAGET:
255 case BLKFRAGET:
256 if (!arg)
257 return -EINVAL;
258 bdi = blk_get_backing_dev_info(bdev);
259 if (bdi == NULL)
260 return -ENOTTY;
261 return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
262 case BLKROGET:
263 return put_int(arg, bdev_read_only(bdev) != 0);
264 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */
265 return put_int(arg, block_size(bdev));
266 case BLKSSZGET: /* get block device logical block size */
267 return put_int(arg, bdev_logical_block_size(bdev));
268 case BLKPBSZGET: /* get block device physical block size */
269 return put_uint(arg, bdev_physical_block_size(bdev));
270 case BLKIOMIN:
271 return put_uint(arg, bdev_io_min(bdev));
272 case BLKIOOPT:
273 return put_uint(arg, bdev_io_opt(bdev));
274 case BLKALIGNOFF:
275 return put_int(arg, bdev_alignment_offset(bdev));
276 case BLKDISCARDZEROES:
277 return put_uint(arg, bdev_discard_zeroes_data(bdev));
278 case BLKSECTGET:
279 return put_ushort(arg, queue_max_sectors(bdev_get_queue(bdev)));
280 case BLKRASET:
281 case BLKFRASET:
282 if(!capable(CAP_SYS_ADMIN))
283 return -EACCES;
284 bdi = blk_get_backing_dev_info(bdev);
285 if (bdi == NULL)
286 return -ENOTTY;
287 bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
288 return 0;
289 case BLKBSZSET:
290 /* set the logical block size */
291 if (!capable(CAP_SYS_ADMIN))
292 return -EACCES;
293 if (!arg)
294 return -EINVAL;
295 if (get_user(n, (int __user *) arg))
296 return -EFAULT;
297 if (!(mode & FMODE_EXCL)) {
298 bdgrab(bdev);
299 if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0)
300 return -EBUSY;
302 ret = set_blocksize(bdev, n);
303 if (!(mode & FMODE_EXCL))
304 blkdev_put(bdev, mode | FMODE_EXCL);
305 return ret;
306 case BLKPG:
307 ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
308 break;
309 case BLKRRPART:
310 ret = blkdev_reread_part(bdev);
311 break;
312 case BLKGETSIZE:
313 size = i_size_read(bdev->bd_inode);
314 if ((size >> 9) > ~0UL)
315 return -EFBIG;
316 return put_ulong(arg, size >> 9);
317 case BLKGETSIZE64:
318 return put_u64(arg, i_size_read(bdev->bd_inode));
319 case BLKTRACESTART:
320 case BLKTRACESTOP:
321 case BLKTRACESETUP:
322 case BLKTRACETEARDOWN:
323 ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg);
324 break;
325 default:
326 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
328 return ret;
330 EXPORT_SYMBOL_GPL(blkdev_ioctl);