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 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; 45 } 46 47 mutex_lock(&bdev->bd_mutex); 48 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; 58 } 59 } 60 disk_part_iter_exit(&piter); 61 62 /* all seems OK */ 63 part = add_partition(disk, partno, start, length, 64 ADDPART_FLAG_NONE); 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; 71 72 bdevp = bdget(part_devt(part)); 73 disk_put_part(part); 74 if (!bdevp) 75 return -ENOMEM; 76 77 mutex_lock(&bdevp->bd_mutex); 78 if (bdevp->bd_openers) { 79 mutex_unlock(&bdevp->bd_mutex); 80 bdput(bdevp); 81 return -EBUSY; 82 } 83 /* all seems OK */ 84 fsync_bdev(bdevp); 85 invalidate_bdev(bdevp); 86 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); 92 93 return 0; 94 default: 95 return -EINVAL; 96 } 97 } 98 99 static int blkdev_reread_part(struct block_device *bdev) 100 { 101 struct gendisk *disk = bdev->bd_disk; 102 int res; 103 104 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; 113 } 114 115 static void blk_ioc_discard_endio(struct bio *bio, int err) 116 { 117 if (err) { 118 if (err == -EOPNOTSUPP) 119 set_bit(BIO_EOPNOTSUPP, &bio->bi_flags); 120 clear_bit(BIO_UPTODATE, &bio->bi_flags); 121 } 122 complete(bio->bi_private); 123 } 124 125 static int blk_ioctl_discard(struct block_device *bdev, uint64_t start, 126 uint64_t len) 127 { 128 struct request_queue *q = bdev_get_queue(bdev); 129 int ret = 0; 130 131 if (start & 511) 132 return -EINVAL; 133 if (len & 511) 134 return -EINVAL; 135 start >>= 9; 136 len >>= 9; 137 138 if (start + len > (bdev->bd_inode->i_size >> 9)) 139 return -EINVAL; 140 141 if (!q->prepare_discard_fn) 142 return -EOPNOTSUPP; 143 144 while (len && !ret) { 145 DECLARE_COMPLETION_ONSTACK(wait); 146 struct bio *bio; 147 148 bio = bio_alloc(GFP_KERNEL, 0); 149 150 bio->bi_end_io = blk_ioc_discard_endio; 151 bio->bi_bdev = bdev; 152 bio->bi_private = &wait; 153 bio->bi_sector = start; 154 155 if (len > q->max_hw_sectors) { 156 bio->bi_size = q->max_hw_sectors << 9; 157 len -= q->max_hw_sectors; 158 start += q->max_hw_sectors; 159 } else { 160 bio->bi_size = len << 9; 161 len = 0; 162 } 163 submit_bio(DISCARD_NOBARRIER, bio); 164 165 wait_for_completion(&wait); 166 167 if (bio_flagged(bio, BIO_EOPNOTSUPP)) 168 ret = -EOPNOTSUPP; 169 else if (!bio_flagged(bio, BIO_UPTODATE)) 170 ret = -EIO; 171 bio_put(bio); 172 } 173 return ret; 174 } 175 176 static int put_ushort(unsigned long arg, unsigned short val) 177 { 178 return put_user(val, (unsigned short __user *)arg); 179 } 180 181 static int put_int(unsigned long arg, int val) 182 { 183 return put_user(val, (int __user *)arg); 184 } 185 186 static int put_long(unsigned long arg, long val) 187 { 188 return put_user(val, (long __user *)arg); 189 } 190 191 static int put_ulong(unsigned long arg, unsigned long val) 192 { 193 return put_user(val, (unsigned long __user *)arg); 194 } 195 196 static int put_u64(unsigned long arg, u64 val) 197 { 198 return put_user(val, (u64 __user *)arg); 199 } 200 201 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode, 202 unsigned cmd, unsigned long arg) 203 { 204 struct gendisk *disk = bdev->bd_disk; 205 int ret; 206 207 if (disk->fops->ioctl) 208 return disk->fops->ioctl(bdev, mode, cmd, arg); 209 210 if (disk->fops->locked_ioctl) { 211 lock_kernel(); 212 ret = disk->fops->locked_ioctl(bdev, mode, cmd, arg); 213 unlock_kernel(); 214 return ret; 215 } 216 217 return -ENOTTY; 218 } 219 /* 220 * For the record: _GPL here is only because somebody decided to slap it 221 * on the previous export. Sheer idiocy, since it wasn't copyrightable 222 * at all and could be open-coded without any exports by anybody who cares. 223 */ 224 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl); 225 226 /* 227 * always keep this in sync with compat_blkdev_ioctl() and 228 * compat_blkdev_locked_ioctl() 229 */ 230 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, 231 unsigned long arg) 232 { 233 struct gendisk *disk = bdev->bd_disk; 234 struct backing_dev_info *bdi; 235 loff_t size; 236 int ret, n; 237 238 switch(cmd) { 239 case BLKFLSBUF: 240 if (!capable(CAP_SYS_ADMIN)) 241 return -EACCES; 242 243 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 244 /* -EINVAL to handle old uncorrected drivers */ 245 if (ret != -EINVAL && ret != -ENOTTY) 246 return ret; 247 248 lock_kernel(); 249 fsync_bdev(bdev); 250 invalidate_bdev(bdev); 251 unlock_kernel(); 252 return 0; 253 254 case BLKROSET: 255 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 256 /* -EINVAL to handle old uncorrected drivers */ 257 if (ret != -EINVAL && ret != -ENOTTY) 258 return ret; 259 if (!capable(CAP_SYS_ADMIN)) 260 return -EACCES; 261 if (get_user(n, (int __user *)(arg))) 262 return -EFAULT; 263 lock_kernel(); 264 set_device_ro(bdev, n); 265 unlock_kernel(); 266 return 0; 267 268 case BLKDISCARD: { 269 uint64_t range[2]; 270 271 if (!(mode & FMODE_WRITE)) 272 return -EBADF; 273 274 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 275 return -EFAULT; 276 277 return blk_ioctl_discard(bdev, range[0], range[1]); 278 } 279 280 case HDIO_GETGEO: { 281 struct hd_geometry geo; 282 283 if (!arg) 284 return -EINVAL; 285 if (!disk->fops->getgeo) 286 return -ENOTTY; 287 288 /* 289 * We need to set the startsect first, the driver may 290 * want to override it. 291 */ 292 geo.start = get_start_sect(bdev); 293 ret = disk->fops->getgeo(bdev, &geo); 294 if (ret) 295 return ret; 296 if (copy_to_user((struct hd_geometry __user *)arg, &geo, 297 sizeof(geo))) 298 return -EFAULT; 299 return 0; 300 } 301 case BLKRAGET: 302 case BLKFRAGET: 303 if (!arg) 304 return -EINVAL; 305 bdi = blk_get_backing_dev_info(bdev); 306 if (bdi == NULL) 307 return -ENOTTY; 308 return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512); 309 case BLKROGET: 310 return put_int(arg, bdev_read_only(bdev) != 0); 311 case BLKBSZGET: /* get the logical block size (cf. BLKSSZGET) */ 312 return put_int(arg, block_size(bdev)); 313 case BLKSSZGET: /* get block device hardware sector size */ 314 return put_int(arg, bdev_hardsect_size(bdev)); 315 case BLKSECTGET: 316 return put_ushort(arg, bdev_get_queue(bdev)->max_sectors); 317 case BLKRASET: 318 case BLKFRASET: 319 if(!capable(CAP_SYS_ADMIN)) 320 return -EACCES; 321 bdi = blk_get_backing_dev_info(bdev); 322 if (bdi == NULL) 323 return -ENOTTY; 324 bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE; 325 return 0; 326 case BLKBSZSET: 327 /* set the logical block size */ 328 if (!capable(CAP_SYS_ADMIN)) 329 return -EACCES; 330 if (!arg) 331 return -EINVAL; 332 if (get_user(n, (int __user *) arg)) 333 return -EFAULT; 334 if (!(mode & FMODE_EXCL) && bd_claim(bdev, &bdev) < 0) 335 return -EBUSY; 336 ret = set_blocksize(bdev, n); 337 if (!(mode & FMODE_EXCL)) 338 bd_release(bdev); 339 return ret; 340 case BLKPG: 341 lock_kernel(); 342 ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg); 343 unlock_kernel(); 344 break; 345 case BLKRRPART: 346 lock_kernel(); 347 ret = blkdev_reread_part(bdev); 348 unlock_kernel(); 349 break; 350 case BLKGETSIZE: 351 size = bdev->bd_inode->i_size; 352 if ((size >> 9) > ~0UL) 353 return -EFBIG; 354 return put_ulong(arg, size >> 9); 355 case BLKGETSIZE64: 356 return put_u64(arg, bdev->bd_inode->i_size); 357 case BLKTRACESTART: 358 case BLKTRACESTOP: 359 case BLKTRACESETUP: 360 case BLKTRACETEARDOWN: 361 lock_kernel(); 362 ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg); 363 unlock_kernel(); 364 break; 365 default: 366 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 367 } 368 return ret; 369 } 370 EXPORT_SYMBOL_GPL(blkdev_ioctl); 371