1 #include <linux/capability.h> 2 #include <linux/blkdev.h> 3 #include <linux/gfp.h> 4 #include <linux/blkpg.h> 5 #include <linux/hdreg.h> 6 #include <linux/backing-dev.h> 7 #include <linux/buffer_head.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, NULL); 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, int secure) 117 { 118 unsigned long flags = 0; 119 120 if (start & 511) 121 return -EINVAL; 122 if (len & 511) 123 return -EINVAL; 124 start >>= 9; 125 len >>= 9; 126 127 if (start + len > (i_size_read(bdev->bd_inode) >> 9)) 128 return -EINVAL; 129 if (secure) 130 flags |= BLKDEV_DISCARD_SECURE; 131 return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, flags); 132 } 133 134 static int put_ushort(unsigned long arg, unsigned short val) 135 { 136 return put_user(val, (unsigned short __user *)arg); 137 } 138 139 static int put_int(unsigned long arg, int val) 140 { 141 return put_user(val, (int __user *)arg); 142 } 143 144 static int put_uint(unsigned long arg, unsigned int val) 145 { 146 return put_user(val, (unsigned int __user *)arg); 147 } 148 149 static int put_long(unsigned long arg, long val) 150 { 151 return put_user(val, (long __user *)arg); 152 } 153 154 static int put_ulong(unsigned long arg, unsigned long val) 155 { 156 return put_user(val, (unsigned long __user *)arg); 157 } 158 159 static int put_u64(unsigned long arg, u64 val) 160 { 161 return put_user(val, (u64 __user *)arg); 162 } 163 164 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode, 165 unsigned cmd, unsigned long arg) 166 { 167 struct gendisk *disk = bdev->bd_disk; 168 169 if (disk->fops->ioctl) 170 return disk->fops->ioctl(bdev, mode, cmd, arg); 171 172 return -ENOTTY; 173 } 174 /* 175 * For the record: _GPL here is only because somebody decided to slap it 176 * on the previous export. Sheer idiocy, since it wasn't copyrightable 177 * at all and could be open-coded without any exports by anybody who cares. 178 */ 179 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl); 180 181 /* 182 * always keep this in sync with compat_blkdev_ioctl() 183 */ 184 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, 185 unsigned long arg) 186 { 187 struct gendisk *disk = bdev->bd_disk; 188 struct backing_dev_info *bdi; 189 loff_t size; 190 int ret, n; 191 192 switch(cmd) { 193 case BLKFLSBUF: 194 if (!capable(CAP_SYS_ADMIN)) 195 return -EACCES; 196 197 ret = __blkdev_driver_ioctl(bdev, mode, 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); 204 return 0; 205 206 case BLKROSET: 207 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 208 /* -EINVAL to handle old uncorrected drivers */ 209 if (ret != -EINVAL && ret != -ENOTTY) 210 return ret; 211 if (!capable(CAP_SYS_ADMIN)) 212 return -EACCES; 213 if (get_user(n, (int __user *)(arg))) 214 return -EFAULT; 215 set_device_ro(bdev, n); 216 return 0; 217 218 case BLKDISCARD: 219 case BLKSECDISCARD: { 220 uint64_t range[2]; 221 222 if (!(mode & FMODE_WRITE)) 223 return -EBADF; 224 225 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 226 return -EFAULT; 227 228 return blk_ioctl_discard(bdev, range[0], range[1], 229 cmd == BLKSECDISCARD); 230 } 231 232 case HDIO_GETGEO: { 233 struct hd_geometry geo; 234 235 if (!arg) 236 return -EINVAL; 237 if (!disk->fops->getgeo) 238 return -ENOTTY; 239 240 /* 241 * We need to set the startsect first, the driver may 242 * want to override it. 243 */ 244 memset(&geo, 0, sizeof(geo)); 245 geo.start = get_start_sect(bdev); 246 ret = disk->fops->getgeo(bdev, &geo); 247 if (ret) 248 return ret; 249 if (copy_to_user((struct hd_geometry __user *)arg, &geo, 250 sizeof(geo))) 251 return -EFAULT; 252 return 0; 253 } 254 case BLKRAGET: 255 case BLKFRAGET: 256 if (!arg) 257 return -EINVAL; 258 bdi = blk_get_backing_dev_info(bdev); 259 if (bdi == NULL) 260 return -ENOTTY; 261 return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512); 262 case BLKROGET: 263 return put_int(arg, bdev_read_only(bdev) != 0); 264 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */ 265 return put_int(arg, block_size(bdev)); 266 case BLKSSZGET: /* get block device logical block size */ 267 return put_int(arg, bdev_logical_block_size(bdev)); 268 case BLKPBSZGET: /* get block device physical block size */ 269 return put_uint(arg, bdev_physical_block_size(bdev)); 270 case BLKIOMIN: 271 return put_uint(arg, bdev_io_min(bdev)); 272 case BLKIOOPT: 273 return put_uint(arg, bdev_io_opt(bdev)); 274 case BLKALIGNOFF: 275 return put_int(arg, bdev_alignment_offset(bdev)); 276 case BLKDISCARDZEROES: 277 return put_uint(arg, bdev_discard_zeroes_data(bdev)); 278 case BLKSECTGET: 279 return put_ushort(arg, queue_max_sectors(bdev_get_queue(bdev))); 280 case BLKRASET: 281 case BLKFRASET: 282 if(!capable(CAP_SYS_ADMIN)) 283 return -EACCES; 284 bdi = blk_get_backing_dev_info(bdev); 285 if (bdi == NULL) 286 return -ENOTTY; 287 bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE; 288 return 0; 289 case BLKBSZSET: 290 /* set the logical block size */ 291 if (!capable(CAP_SYS_ADMIN)) 292 return -EACCES; 293 if (!arg) 294 return -EINVAL; 295 if (get_user(n, (int __user *) arg)) 296 return -EFAULT; 297 if (!(mode & FMODE_EXCL) && 298 blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0) 299 return -EBUSY; 300 ret = set_blocksize(bdev, n); 301 if (!(mode & FMODE_EXCL)) 302 blkdev_put(bdev, mode | FMODE_EXCL); 303 return ret; 304 case BLKPG: 305 ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg); 306 break; 307 case BLKRRPART: 308 ret = blkdev_reread_part(bdev); 309 break; 310 case BLKGETSIZE: 311 size = i_size_read(bdev->bd_inode); 312 if ((size >> 9) > ~0UL) 313 return -EFBIG; 314 return put_ulong(arg, size >> 9); 315 case BLKGETSIZE64: 316 return put_u64(arg, i_size_read(bdev->bd_inode)); 317 case BLKTRACESTART: 318 case BLKTRACESTOP: 319 case BLKTRACESETUP: 320 case BLKTRACETEARDOWN: 321 ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg); 322 break; 323 default: 324 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 325 } 326 return ret; 327 } 328 EXPORT_SYMBOL_GPL(blkdev_ioctl); 329