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 int blk_ioctl_discard(struct block_device *bdev, uint64_t start, 116 uint64_t len) 117 { 118 if (start & 511) 119 return -EINVAL; 120 if (len & 511) 121 return -EINVAL; 122 start >>= 9; 123 len >>= 9; 124 125 if (start + len > (bdev->bd_inode->i_size >> 9)) 126 return -EINVAL; 127 return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, 128 DISCARD_FL_WAIT); 129 } 130 131 static int put_ushort(unsigned long arg, unsigned short val) 132 { 133 return put_user(val, (unsigned short __user *)arg); 134 } 135 136 static int put_int(unsigned long arg, int val) 137 { 138 return put_user(val, (int __user *)arg); 139 } 140 141 static int put_uint(unsigned long arg, unsigned int val) 142 { 143 return put_user(val, (unsigned int __user *)arg); 144 } 145 146 static int put_long(unsigned long arg, long val) 147 { 148 return put_user(val, (long __user *)arg); 149 } 150 151 static int put_ulong(unsigned long arg, unsigned long val) 152 { 153 return put_user(val, (unsigned long __user *)arg); 154 } 155 156 static int put_u64(unsigned long arg, u64 val) 157 { 158 return put_user(val, (u64 __user *)arg); 159 } 160 161 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode, 162 unsigned cmd, unsigned long arg) 163 { 164 struct gendisk *disk = bdev->bd_disk; 165 int ret; 166 167 if (disk->fops->ioctl) 168 return disk->fops->ioctl(bdev, mode, cmd, arg); 169 170 if (disk->fops->locked_ioctl) { 171 lock_kernel(); 172 ret = disk->fops->locked_ioctl(bdev, mode, cmd, arg); 173 unlock_kernel(); 174 return ret; 175 } 176 177 return -ENOTTY; 178 } 179 /* 180 * For the record: _GPL here is only because somebody decided to slap it 181 * on the previous export. Sheer idiocy, since it wasn't copyrightable 182 * at all and could be open-coded without any exports by anybody who cares. 183 */ 184 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl); 185 186 /* 187 * always keep this in sync with compat_blkdev_ioctl() and 188 * compat_blkdev_locked_ioctl() 189 */ 190 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, 191 unsigned long arg) 192 { 193 struct gendisk *disk = bdev->bd_disk; 194 struct backing_dev_info *bdi; 195 loff_t size; 196 int ret, n; 197 198 switch(cmd) { 199 case BLKFLSBUF: 200 if (!capable(CAP_SYS_ADMIN)) 201 return -EACCES; 202 203 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 204 /* -EINVAL to handle old uncorrected drivers */ 205 if (ret != -EINVAL && ret != -ENOTTY) 206 return ret; 207 208 lock_kernel(); 209 fsync_bdev(bdev); 210 invalidate_bdev(bdev); 211 unlock_kernel(); 212 return 0; 213 214 case BLKROSET: 215 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 216 /* -EINVAL to handle old uncorrected drivers */ 217 if (ret != -EINVAL && ret != -ENOTTY) 218 return ret; 219 if (!capable(CAP_SYS_ADMIN)) 220 return -EACCES; 221 if (get_user(n, (int __user *)(arg))) 222 return -EFAULT; 223 lock_kernel(); 224 set_device_ro(bdev, n); 225 unlock_kernel(); 226 return 0; 227 228 case BLKDISCARD: { 229 uint64_t range[2]; 230 231 if (!(mode & FMODE_WRITE)) 232 return -EBADF; 233 234 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 235 return -EFAULT; 236 237 return blk_ioctl_discard(bdev, range[0], range[1]); 238 } 239 240 case HDIO_GETGEO: { 241 struct hd_geometry geo; 242 243 if (!arg) 244 return -EINVAL; 245 if (!disk->fops->getgeo) 246 return -ENOTTY; 247 248 /* 249 * We need to set the startsect first, the driver may 250 * want to override it. 251 */ 252 geo.start = get_start_sect(bdev); 253 ret = disk->fops->getgeo(bdev, &geo); 254 if (ret) 255 return ret; 256 if (copy_to_user((struct hd_geometry __user *)arg, &geo, 257 sizeof(geo))) 258 return -EFAULT; 259 return 0; 260 } 261 case BLKRAGET: 262 case BLKFRAGET: 263 if (!arg) 264 return -EINVAL; 265 bdi = blk_get_backing_dev_info(bdev); 266 if (bdi == NULL) 267 return -ENOTTY; 268 return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512); 269 case BLKROGET: 270 return put_int(arg, bdev_read_only(bdev) != 0); 271 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */ 272 return put_int(arg, block_size(bdev)); 273 case BLKSSZGET: /* get block device logical block size */ 274 return put_int(arg, bdev_logical_block_size(bdev)); 275 case BLKPBSZGET: /* get block device physical block size */ 276 return put_uint(arg, bdev_physical_block_size(bdev)); 277 case BLKIOMIN: 278 return put_uint(arg, bdev_io_min(bdev)); 279 case BLKIOOPT: 280 return put_uint(arg, bdev_io_opt(bdev)); 281 case BLKALIGNOFF: 282 return put_int(arg, bdev_alignment_offset(bdev)); 283 case BLKDISCARDZEROES: 284 return put_uint(arg, bdev_discard_zeroes_data(bdev)); 285 case BLKSECTGET: 286 return put_ushort(arg, queue_max_sectors(bdev_get_queue(bdev))); 287 case BLKRASET: 288 case BLKFRASET: 289 if(!capable(CAP_SYS_ADMIN)) 290 return -EACCES; 291 bdi = blk_get_backing_dev_info(bdev); 292 if (bdi == NULL) 293 return -ENOTTY; 294 bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE; 295 return 0; 296 case BLKBSZSET: 297 /* set the logical block size */ 298 if (!capable(CAP_SYS_ADMIN)) 299 return -EACCES; 300 if (!arg) 301 return -EINVAL; 302 if (get_user(n, (int __user *) arg)) 303 return -EFAULT; 304 if (!(mode & FMODE_EXCL) && bd_claim(bdev, &bdev) < 0) 305 return -EBUSY; 306 ret = set_blocksize(bdev, n); 307 if (!(mode & FMODE_EXCL)) 308 bd_release(bdev); 309 return ret; 310 case BLKPG: 311 lock_kernel(); 312 ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg); 313 unlock_kernel(); 314 break; 315 case BLKRRPART: 316 lock_kernel(); 317 ret = blkdev_reread_part(bdev); 318 unlock_kernel(); 319 break; 320 case BLKGETSIZE: 321 size = bdev->bd_inode->i_size; 322 if ((size >> 9) > ~0UL) 323 return -EFBIG; 324 return put_ulong(arg, size >> 9); 325 case BLKGETSIZE64: 326 return put_u64(arg, bdev->bd_inode->i_size); 327 case BLKTRACESTART: 328 case BLKTRACESTOP: 329 case BLKTRACESETUP: 330 case BLKTRACETEARDOWN: 331 lock_kernel(); 332 ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg); 333 unlock_kernel(); 334 break; 335 default: 336 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 337 } 338 return ret; 339 } 340 EXPORT_SYMBOL_GPL(blkdev_ioctl); 341