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/buffer_head.h>
9#include <linux/blktrace_api.h>
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;
16 struct hd_struct *part;
17 struct blkpg_ioctl_arg a;
18 struct blkpg_partition p;
19 struct disk_part_iter piter;
20 long long start, length;
21 int partno;
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;
32 partno = p.pno;
33 if (partno <= 0)
34 return -EINVAL;
35 switch (a.op) {
36 case BLKPG_ADD_PARTITION:
37 start = p.start >> 9;
38 length = p.length >> 9;
39
40 if (sizeof(sector_t) == sizeof(long) &&
41 sizeof(long long) > sizeof(long)) {
42 long pstart = start, plength = length;
43 if (pstart != start || plength != length
44 || pstart < 0 || plength < 0)
45 return -EINVAL;
46 }
47
48 mutex_lock(&bdev->bd_mutex);
49
50
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);
57 mutex_unlock(&bdev->bd_mutex);
58 return -EBUSY;
59 }
60 }
61 disk_part_iter_exit(&piter);
62
63
64 part = add_partition(disk, partno, start, length,
65 ADDPART_FLAG_NONE, NULL);
66 mutex_unlock(&bdev->bd_mutex);
67 return IS_ERR(part) ? PTR_ERR(part) : 0;
68 case BLKPG_DEL_PARTITION:
69 part = disk_get_part(disk, partno);
70 if (!part)
71 return -ENXIO;
72
73 bdevp = bdget(part_devt(part));
74 disk_put_part(part);
75 if (!bdevp)
76 return -ENOMEM;
77
78 mutex_lock(&bdevp->bd_mutex);
79 if (bdevp->bd_openers) {
80 mutex_unlock(&bdevp->bd_mutex);
81 bdput(bdevp);
82 return -EBUSY;
83 }
84
85 fsync_bdev(bdevp);
86 invalidate_bdev(bdevp);
87
88 mutex_lock_nested(&bdev->bd_mutex, 1);
89 delete_partition(disk, partno);
90 mutex_unlock(&bdev->bd_mutex);
91 mutex_unlock(&bdevp->bd_mutex);
92 bdput(bdevp);
93
94 return 0;
95 default:
96 return -EINVAL;
97 }
98}
99
100static int blkdev_reread_part(struct block_device *bdev)
101{
102 struct gendisk *disk = bdev->bd_disk;
103 int res;
104
105 if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains)
106 return -EINVAL;
107 if (!capable(CAP_SYS_ADMIN))
108 return -EACCES;
109 if (!mutex_trylock(&bdev->bd_mutex))
110 return -EBUSY;
111 res = rescan_partitions(disk, bdev);
112 mutex_unlock(&bdev->bd_mutex);
113 return res;
114}
115
116static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
117 uint64_t len, int secure)
118{
119 unsigned long flags = 0;
120
121 if (start & 511)
122 return -EINVAL;
123 if (len & 511)
124 return -EINVAL;
125 start >>= 9;
126 len >>= 9;
127
128 if (start + len > (i_size_read(bdev->bd_inode) >> 9))
129 return -EINVAL;
130 if (secure)
131 flags |= BLKDEV_DISCARD_SECURE;
132 return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, flags);
133}
134
135static int put_ushort(unsigned long arg, unsigned short val)
136{
137 return put_user(val, (unsigned short __user *)arg);
138}
139
140static int put_int(unsigned long arg, int val)
141{
142 return put_user(val, (int __user *)arg);
143}
144
145static int put_uint(unsigned long arg, unsigned int val)
146{
147 return put_user(val, (unsigned int __user *)arg);
148}
149
150static int put_long(unsigned long arg, long val)
151{
152 return put_user(val, (long __user *)arg);
153}
154
155static int put_ulong(unsigned long arg, unsigned long val)
156{
157 return put_user(val, (unsigned long __user *)arg);
158}
159
160static int put_u64(unsigned long arg, u64 val)
161{
162 return put_user(val, (u64 __user *)arg);
163}
164
165int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
166 unsigned cmd, unsigned long arg)
167{
168 struct gendisk *disk = bdev->bd_disk;
169
170 if (disk->fops->ioctl)
171 return disk->fops->ioctl(bdev, mode, cmd, arg);
172
173 return -ENOTTY;
174}
175
176
177
178
179
180EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
181
182
183
184
185int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
186 unsigned long arg)
187{
188 struct gendisk *disk = bdev->bd_disk;
189 struct backing_dev_info *bdi;
190 loff_t size;
191 int ret, n;
192
193 switch(cmd) {
194 case BLKFLSBUF:
195 if (!capable(CAP_SYS_ADMIN))
196 return -EACCES;
197
198 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
199
200 if (ret != -EINVAL && ret != -ENOTTY)
201 return ret;
202
203 fsync_bdev(bdev);
204 invalidate_bdev(bdev);
205 return 0;
206
207 case BLKROSET:
208 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
209
210 if (ret != -EINVAL && ret != -ENOTTY)
211 return ret;
212 if (!capable(CAP_SYS_ADMIN))
213 return -EACCES;
214 if (get_user(n, (int __user *)(arg)))
215 return -EFAULT;
216 set_device_ro(bdev, n);
217 return 0;
218
219 case BLKDISCARD:
220 case BLKSECDISCARD: {
221 uint64_t range[2];
222
223 if (!(mode & FMODE_WRITE))
224 return -EBADF;
225
226 if (copy_from_user(range, (void __user *)arg, sizeof(range)))
227 return -EFAULT;
228
229 return blk_ioctl_discard(bdev, range[0], range[1],
230 cmd == BLKSECDISCARD);
231 }
232
233 case HDIO_GETGEO: {
234 struct hd_geometry geo;
235
236 if (!arg)
237 return -EINVAL;
238 if (!disk->fops->getgeo)
239 return -ENOTTY;
240
241
242
243
244
245 memset(&geo, 0, sizeof(geo));
246 geo.start = get_start_sect(bdev);
247 ret = disk->fops->getgeo(bdev, &geo);
248 if (ret)
249 return ret;
250 if (copy_to_user((struct hd_geometry __user *)arg, &geo,
251 sizeof(geo)))
252 return -EFAULT;
253 return 0;
254 }
255 case BLKRAGET:
256 case BLKFRAGET:
257 if (!arg)
258 return -EINVAL;
259 bdi = blk_get_backing_dev_info(bdev);
260 if (bdi == NULL)
261 return -ENOTTY;
262 return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
263 case BLKROGET:
264 return put_int(arg, bdev_read_only(bdev) != 0);
265 case BLKBSZGET:
266 return put_int(arg, block_size(bdev));
267 case BLKSSZGET:
268 return put_int(arg, bdev_logical_block_size(bdev));
269 case BLKPBSZGET:
270 return put_uint(arg, bdev_physical_block_size(bdev));
271 case BLKIOMIN:
272 return put_uint(arg, bdev_io_min(bdev));
273 case BLKIOOPT:
274 return put_uint(arg, bdev_io_opt(bdev));
275 case BLKALIGNOFF:
276 return put_int(arg, bdev_alignment_offset(bdev));
277 case BLKDISCARDZEROES:
278 return put_uint(arg, bdev_discard_zeroes_data(bdev));
279 case BLKSECTGET:
280 return put_ushort(arg, queue_max_sectors(bdev_get_queue(bdev)));
281 case BLKRASET:
282 case BLKFRASET:
283 if(!capable(CAP_SYS_ADMIN))
284 return -EACCES;
285 bdi = blk_get_backing_dev_info(bdev);
286 if (bdi == NULL)
287 return -ENOTTY;
288 bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
289 return 0;
290 case BLKBSZSET:
291
292 if (!capable(CAP_SYS_ADMIN))
293 return -EACCES;
294 if (!arg)
295 return -EINVAL;
296 if (get_user(n, (int __user *) arg))
297 return -EFAULT;
298 if (!(mode & FMODE_EXCL)) {
299 bdgrab(bdev);
300 if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0)
301 return -EBUSY;
302 }
303 ret = set_blocksize(bdev, n);
304 if (!(mode & FMODE_EXCL))
305 blkdev_put(bdev, mode | FMODE_EXCL);
306 return ret;
307 case BLKPG:
308 ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
309 break;
310 case BLKRRPART:
311 ret = blkdev_reread_part(bdev);
312 break;
313 case BLKGETSIZE:
314 size = i_size_read(bdev->bd_inode);
315 if ((size >> 9) > ~0UL)
316 return -EFBIG;
317 return put_ulong(arg, size >> 9);
318 case BLKGETSIZE64:
319 return put_u64(arg, i_size_read(bdev->bd_inode));
320 case BLKTRACESTART:
321 case BLKTRACESTOP:
322 case BLKTRACESETUP:
323 case BLKTRACETEARDOWN:
324 ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg);
325 break;
326 default:
327 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
328 }
329 return ret;
330}
331EXPORT_SYMBOL_GPL(blkdev_ioctl);
332
