[PATCH] get rid of struct file use in blkdev_ioctl() BLKBSZSET
[linux-2.6.git] / block / ioctl.c
1 #include <linux/capability.h>
2 #include <linux/blkdev.h>
3 #include <linux/blkpg.h>
4 #include <linux/hdreg.h>
5 #include <linux/backing-dev.h>
6 #include <linux/buffer_head.h>
7 #include <linux/smp_lock.h>
8 #include <linux/blktrace_api.h>
9 #include <asm/uaccess.h>
10
11 static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
12 {
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;
21         int err;
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                         /* check for fit in a hd_struct */ 
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                         /* overlap? */
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                         /* all seems OK */
64                         err = add_partition(disk, partno, start, length,
65                                             ADDPART_FLAG_NONE);
66                         mutex_unlock(&bdev->bd_mutex);
67                         return err;
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                         /* all seems OK */
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
100 static int blkdev_reread_part(struct block_device *bdev)
101 {
102         struct gendisk *disk = bdev->bd_disk;
103         int res;
104
105         if (!disk_partitionable(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
116 static void blk_ioc_discard_endio(struct bio *bio, int err)
117 {
118         if (err) {
119                 if (err == -EOPNOTSUPP)
120                         set_bit(BIO_EOPNOTSUPP, &bio->bi_flags);
121                 clear_bit(BIO_UPTODATE, &bio->bi_flags);
122         }
123         complete(bio->bi_private);
124 }
125
126 static int blk_ioctl_discard(struct block_device *bdev, uint64_t start,
127                              uint64_t len)
128 {
129         struct request_queue *q = bdev_get_queue(bdev);
130         int ret = 0;
131
132         if (start & 511)
133                 return -EINVAL;
134         if (len & 511)
135                 return -EINVAL;
136         start >>= 9;
137         len >>= 9;
138
139         if (start + len > (bdev->bd_inode->i_size >> 9))
140                 return -EINVAL;
141
142         if (!q->prepare_discard_fn)
143                 return -EOPNOTSUPP;
144
145         while (len && !ret) {
146                 DECLARE_COMPLETION_ONSTACK(wait);
147                 struct bio *bio;
148
149                 bio = bio_alloc(GFP_KERNEL, 0);
150                 if (!bio)
151                         return -ENOMEM;
152
153                 bio->bi_end_io = blk_ioc_discard_endio;
154                 bio->bi_bdev = bdev;
155                 bio->bi_private = &wait;
156                 bio->bi_sector = start;
157
158                 if (len > q->max_hw_sectors) {
159                         bio->bi_size = q->max_hw_sectors << 9;
160                         len -= q->max_hw_sectors;
161                         start += q->max_hw_sectors;
162                 } else {
163                         bio->bi_size = len << 9;
164                         len = 0;
165                 }
166                 submit_bio(DISCARD_NOBARRIER, bio);
167
168                 wait_for_completion(&wait);
169
170                 if (bio_flagged(bio, BIO_EOPNOTSUPP))
171                         ret = -EOPNOTSUPP;
172                 else if (!bio_flagged(bio, BIO_UPTODATE))
173                         ret = -EIO;
174                 bio_put(bio);
175         }
176         return ret;
177 }
178
179 static int put_ushort(unsigned long arg, unsigned short val)
180 {
181         return put_user(val, (unsigned short __user *)arg);
182 }
183
184 static int put_int(unsigned long arg, int val)
185 {
186         return put_user(val, (int __user *)arg);
187 }
188
189 static int put_long(unsigned long arg, long val)
190 {
191         return put_user(val, (long __user *)arg);
192 }
193
194 static int put_ulong(unsigned long arg, unsigned long val)
195 {
196         return put_user(val, (unsigned long __user *)arg);
197 }
198
199 static int put_u64(unsigned long arg, u64 val)
200 {
201         return put_user(val, (u64 __user *)arg);
202 }
203
204 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
205                         unsigned cmd, unsigned long arg)
206 {
207         struct gendisk *disk = bdev->bd_disk;
208         int ret;
209
210         if (disk->fops->ioctl)
211                 return disk->fops->ioctl(bdev, mode, cmd, arg);
212
213         if (disk->fops->locked_ioctl) {
214                 lock_kernel();
215                 ret = disk->fops->locked_ioctl(bdev, mode, cmd, arg);
216                 unlock_kernel();
217                 return ret;
218         }
219
220         return -ENOTTY;
221 }
222 /*
223  * For the record: _GPL here is only because somebody decided to slap it
224  * on the previous export.  Sheer idiocy, since it wasn't copyrightable
225  * at all and could be open-coded without any exports by anybody who cares.
226  */
227 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
228
229 /*
230  * always keep this in sync with compat_blkdev_ioctl() and
231  * compat_blkdev_locked_ioctl()
232  */
233 int blkdev_ioctl(struct inode *inode, struct file *file, unsigned cmd,
234                         unsigned long arg)
235 {
236         struct block_device *bdev = inode->i_bdev;
237         struct gendisk *disk = bdev->bd_disk;
238         struct backing_dev_info *bdi;
239         loff_t size;
240         int ret, n;
241         fmode_t mode = 0;
242         if (file) {
243                 mode = file->f_mode;
244                 if (file->f_flags & O_NDELAY)
245                         mode |= FMODE_NDELAY_NOW;
246         }
247
248         switch(cmd) {
249         case BLKFLSBUF:
250                 if (!capable(CAP_SYS_ADMIN))
251                         return -EACCES;
252
253                 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
254                 /* -EINVAL to handle old uncorrected drivers */
255                 if (ret != -EINVAL && ret != -ENOTTY)
256                         return ret;
257
258                 lock_kernel();
259                 fsync_bdev(bdev);
260                 invalidate_bdev(bdev);
261                 unlock_kernel();
262                 return 0;
263
264         case BLKROSET:
265                 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
266                 /* -EINVAL to handle old uncorrected drivers */
267                 if (ret != -EINVAL && ret != -ENOTTY)
268                         return ret;
269                 if (!capable(CAP_SYS_ADMIN))
270                         return -EACCES;
271                 if (get_user(n, (int __user *)(arg)))
272                         return -EFAULT;
273                 lock_kernel();
274                 set_device_ro(bdev, n);
275                 unlock_kernel();
276                 return 0;
277
278         case BLKDISCARD: {
279                 uint64_t range[2];
280
281                 if (!(mode & FMODE_WRITE))
282                         return -EBADF;
283
284                 if (copy_from_user(range, (void __user *)arg, sizeof(range)))
285                         return -EFAULT;
286
287                 return blk_ioctl_discard(bdev, range[0], range[1]);
288         }
289
290         case HDIO_GETGEO: {
291                 struct hd_geometry geo;
292
293                 if (!arg)
294                         return -EINVAL;
295                 if (!disk->fops->getgeo)
296                         return -ENOTTY;
297
298                 /*
299                  * We need to set the startsect first, the driver may
300                  * want to override it.
301                  */
302                 geo.start = get_start_sect(bdev);
303                 ret = disk->fops->getgeo(bdev, &geo);
304                 if (ret)
305                         return ret;
306                 if (copy_to_user((struct hd_geometry __user *)arg, &geo,
307                                         sizeof(geo)))
308                         return -EFAULT;
309                 return 0;
310         }
311         case BLKRAGET:
312         case BLKFRAGET:
313                 if (!arg)
314                         return -EINVAL;
315                 bdi = blk_get_backing_dev_info(bdev);
316                 if (bdi == NULL)
317                         return -ENOTTY;
318                 return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
319         case BLKROGET:
320                 return put_int(arg, bdev_read_only(bdev) != 0);
321         case BLKBSZGET: /* get the logical block size (cf. BLKSSZGET) */
322                 return put_int(arg, block_size(bdev));
323         case BLKSSZGET: /* get block device hardware sector size */
324                 return put_int(arg, bdev_hardsect_size(bdev));
325         case BLKSECTGET:
326                 return put_ushort(arg, bdev_get_queue(bdev)->max_sectors);
327         case BLKRASET:
328         case BLKFRASET:
329                 if(!capable(CAP_SYS_ADMIN))
330                         return -EACCES;
331                 bdi = blk_get_backing_dev_info(bdev);
332                 if (bdi == NULL)
333                         return -ENOTTY;
334                 lock_kernel();
335                 bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
336                 unlock_kernel();
337                 return 0;
338         case BLKBSZSET:
339                 /* set the logical block size */
340                 if (!capable(CAP_SYS_ADMIN))
341                         return -EACCES;
342                 if (!arg)
343                         return -EINVAL;
344                 if (get_user(n, (int __user *) arg))
345                         return -EFAULT;
346                 if (!(mode & FMODE_EXCL) && bd_claim(bdev, &bdev) < 0)
347                         return -EBUSY;
348                 ret = set_blocksize(bdev, n);
349                 if (!(mode & FMODE_EXCL))
350                         bd_release(bdev);
351                 return ret;
352         case BLKPG:
353                 lock_kernel();
354                 ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
355                 unlock_kernel();
356                 break;
357         case BLKRRPART:
358                 lock_kernel();
359                 ret = blkdev_reread_part(bdev);
360                 unlock_kernel();
361                 break;
362         case BLKGETSIZE:
363                 size = bdev->bd_inode->i_size;
364                 if ((size >> 9) > ~0UL)
365                         return -EFBIG;
366                 return put_ulong(arg, size >> 9);
367         case BLKGETSIZE64:
368                 return put_u64(arg, bdev->bd_inode->i_size);
369         case BLKTRACESTART:
370         case BLKTRACESTOP:
371         case BLKTRACESETUP:
372         case BLKTRACETEARDOWN:
373                 lock_kernel();
374                 ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg);
375                 unlock_kernel();
376                 break;
377         default:
378                 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
379         }
380         return ret;
381 }
382 EXPORT_SYMBOL_GPL(blkdev_ioctl);