blob: 5e03f5157ef93b2d2b3bc447a36ceba566a2336d [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001#include <linux/sched.h> /* for capable() */
2#include <linux/blkdev.h>
3#include <linux/blkpg.h>
4#include <linux/backing-dev.h>
5#include <linux/buffer_head.h>
6#include <linux/smp_lock.h>
7#include <asm/uaccess.h>
8
9static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg)
10{
11 struct block_device *bdevp;
12 struct gendisk *disk;
13 struct blkpg_ioctl_arg a;
14 struct blkpg_partition p;
15 long long start, length;
16 int part;
17 int i;
18
19 if (!capable(CAP_SYS_ADMIN))
20 return -EACCES;
21 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg)))
22 return -EFAULT;
23 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition)))
24 return -EFAULT;
25 disk = bdev->bd_disk;
26 if (bdev != bdev->bd_contains)
27 return -EINVAL;
28 part = p.pno;
29 if (part <= 0 || part >= disk->minors)
30 return -EINVAL;
31 switch (a.op) {
32 case BLKPG_ADD_PARTITION:
33 start = p.start >> 9;
34 length = p.length >> 9;
35 /* check for fit in a hd_struct */
36 if (sizeof(sector_t) == sizeof(long) &&
37 sizeof(long long) > sizeof(long)) {
38 long pstart = start, plength = length;
39 if (pstart != start || plength != length
40 || pstart < 0 || plength < 0)
41 return -EINVAL;
42 }
43 /* partition number in use? */
44 down(&bdev->bd_sem);
45 if (disk->part[part - 1]) {
46 up(&bdev->bd_sem);
47 return -EBUSY;
48 }
49 /* overlap? */
50 for (i = 0; i < disk->minors - 1; i++) {
51 struct hd_struct *s = disk->part[i];
52
53 if (!s)
54 continue;
55 if (!(start+length <= s->start_sect ||
56 start >= s->start_sect + s->nr_sects)) {
57 up(&bdev->bd_sem);
58 return -EBUSY;
59 }
60 }
61 /* all seems OK */
62 add_partition(disk, part, start, length);
63 up(&bdev->bd_sem);
64 return 0;
65 case BLKPG_DEL_PARTITION:
66 if (!disk->part[part-1])
67 return -ENXIO;
68 if (disk->part[part - 1]->nr_sects == 0)
69 return -ENXIO;
70 bdevp = bdget_disk(disk, part);
71 if (!bdevp)
72 return -ENOMEM;
73 down(&bdevp->bd_sem);
74 if (bdevp->bd_openers) {
75 up(&bdevp->bd_sem);
76 bdput(bdevp);
77 return -EBUSY;
78 }
79 /* all seems OK */
80 fsync_bdev(bdevp);
81 invalidate_bdev(bdevp, 0);
82
83 down(&bdev->bd_sem);
84 delete_partition(disk, part);
85 up(&bdev->bd_sem);
86 up(&bdevp->bd_sem);
87 bdput(bdevp);
88
89 return 0;
90 default:
91 return -EINVAL;
92 }
93}
94
95static int blkdev_reread_part(struct block_device *bdev)
96{
97 struct gendisk *disk = bdev->bd_disk;
98 int res;
99
100 if (disk->minors == 1 || bdev != bdev->bd_contains)
101 return -EINVAL;
102 if (!capable(CAP_SYS_ADMIN))
103 return -EACCES;
104 if (down_trylock(&bdev->bd_sem))
105 return -EBUSY;
106 res = rescan_partitions(disk, bdev);
107 up(&bdev->bd_sem);
108 return res;
109}
110
111static int put_ushort(unsigned long arg, unsigned short val)
112{
113 return put_user(val, (unsigned short __user *)arg);
114}
115
116static int put_int(unsigned long arg, int val)
117{
118 return put_user(val, (int __user *)arg);
119}
120
121static int put_long(unsigned long arg, long val)
122{
123 return put_user(val, (long __user *)arg);
124}
125
126static int put_ulong(unsigned long arg, unsigned long val)
127{
128 return put_user(val, (unsigned long __user *)arg);
129}
130
131static int put_u64(unsigned long arg, u64 val)
132{
133 return put_user(val, (u64 __user *)arg);
134}
135
136int blkdev_ioctl(struct inode *inode, struct file *file, unsigned cmd,
137 unsigned long arg)
138{
139 struct block_device *bdev = inode->i_bdev;
140 struct gendisk *disk = bdev->bd_disk;
141 struct backing_dev_info *bdi;
142 int ret, n;
143
144 switch (cmd) {
145 case BLKRAGET:
146 case BLKFRAGET:
147 if (!arg)
148 return -EINVAL;
149 bdi = blk_get_backing_dev_info(bdev);
150 if (bdi == NULL)
151 return -ENOTTY;
152 return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512);
153 case BLKROGET:
154 return put_int(arg, bdev_read_only(bdev) != 0);
155 case BLKBSZGET: /* get the logical block size (cf. BLKSSZGET) */
156 return put_int(arg, block_size(bdev));
157 case BLKSSZGET: /* get block device hardware sector size */
158 return put_int(arg, bdev_hardsect_size(bdev));
159 case BLKSECTGET:
160 return put_ushort(arg, bdev_get_queue(bdev)->max_sectors);
161 case BLKRASET:
162 case BLKFRASET:
163 if(!capable(CAP_SYS_ADMIN))
164 return -EACCES;
165 bdi = blk_get_backing_dev_info(bdev);
166 if (bdi == NULL)
167 return -ENOTTY;
168 bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE;
169 return 0;
170 case BLKBSZSET:
171 /* set the logical block size */
172 if (!capable(CAP_SYS_ADMIN))
173 return -EACCES;
174 if (!arg)
175 return -EINVAL;
176 if (get_user(n, (int __user *) arg))
177 return -EFAULT;
178 if (bd_claim(bdev, file) < 0)
179 return -EBUSY;
180 ret = set_blocksize(bdev, n);
181 bd_release(bdev);
182 return ret;
183 case BLKPG:
184 return blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
185 case BLKRRPART:
186 return blkdev_reread_part(bdev);
187 case BLKGETSIZE:
188 if ((bdev->bd_inode->i_size >> 9) > ~0UL)
189 return -EFBIG;
190 return put_ulong(arg, bdev->bd_inode->i_size >> 9);
191 case BLKGETSIZE64:
192 return put_u64(arg, bdev->bd_inode->i_size);
193 case BLKFLSBUF:
194 if (!capable(CAP_SYS_ADMIN))
195 return -EACCES;
196 if (disk->fops->ioctl) {
197 ret = disk->fops->ioctl(inode, file, cmd, arg);
198 /* -EINVAL to handle old uncorrected drivers */
199 if (ret != -EINVAL && ret != -ENOTTY)
200 return ret;
201 }
202 fsync_bdev(bdev);
203 invalidate_bdev(bdev, 0);
204 return 0;
205 case BLKROSET:
206 if (disk->fops->ioctl) {
207 ret = disk->fops->ioctl(inode, file, cmd, arg);
208 /* -EINVAL to handle old uncorrected drivers */
209 if (ret != -EINVAL && ret != -ENOTTY)
210 return ret;
211 }
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 default:
219 if (disk->fops->ioctl)
220 return disk->fops->ioctl(inode, file, cmd, arg);
221 }
222 return -ENOTTY;
223}
224
225/* Most of the generic ioctls are handled in the normal fallback path.
226 This assumes the blkdev's low level compat_ioctl always returns
227 ENOIOCTLCMD for unknown ioctls. */
228long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
229{
230 struct block_device *bdev = file->f_dentry->d_inode->i_bdev;
231 struct gendisk *disk = bdev->bd_disk;
232 int ret = -ENOIOCTLCMD;
233 if (disk->fops->compat_ioctl) {
234 lock_kernel();
235 ret = disk->fops->compat_ioctl(file, cmd, arg);
236 unlock_kernel();
237 }
238 return ret;
239}