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/smp_lock.h> 9 #include <linux/blktrace_api.h> 10 #include <asm/uaccess.h> 11 12 static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg) 13 { 14 struct block_device *bdevp; 15 struct gendisk *disk; 16 struct hd_struct *part; 17 struct blkpg_ioctl_arg a; 18 struct blkpg_partition p; 19 struct disk_part_iter piter; 20 long long start, length; 21 int partno; 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 part = add_partition(disk, partno, start, length, 65 ADDPART_FLAG_NONE); 66 mutex_unlock(&bdev->bd_mutex); 67 return IS_ERR(part) ? PTR_ERR(part) : 0; 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 int blk_ioctl_discard(struct block_device *bdev, uint64_t start, 117 uint64_t len) 118 { 119 if (start & 511) 120 return -EINVAL; 121 if (len & 511) 122 return -EINVAL; 123 start >>= 9; 124 len >>= 9; 125 126 if (start + len > (bdev->bd_inode->i_size >> 9)) 127 return -EINVAL; 128 return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, 129 BLKDEV_IFL_WAIT); 130 } 131 132 static int put_ushort(unsigned long arg, unsigned short val) 133 { 134 return put_user(val, (unsigned short __user *)arg); 135 } 136 137 static int put_int(unsigned long arg, int val) 138 { 139 return put_user(val, (int __user *)arg); 140 } 141 142 static int put_uint(unsigned long arg, unsigned int val) 143 { 144 return put_user(val, (unsigned int __user *)arg); 145 } 146 147 static int put_long(unsigned long arg, long val) 148 { 149 return put_user(val, (long __user *)arg); 150 } 151 152 static int put_ulong(unsigned long arg, unsigned long val) 153 { 154 return put_user(val, (unsigned long __user *)arg); 155 } 156 157 static int put_u64(unsigned long arg, u64 val) 158 { 159 return put_user(val, (u64 __user *)arg); 160 } 161 162 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode, 163 unsigned cmd, unsigned long arg) 164 { 165 struct gendisk *disk = bdev->bd_disk; 166 167 if (disk->fops->ioctl) 168 return disk->fops->ioctl(bdev, mode, cmd, arg); 169 170 return -ENOTTY; 171 } 172 /* 173 * For the record: _GPL here is only because somebody decided to slap it 174 * on the previous export. Sheer idiocy, since it wasn't copyrightable 175 * at all and could be open-coded without any exports by anybody who cares. 176 */ 177 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl); 178 179 /* 180 * always keep this in sync with compat_blkdev_ioctl() 181 */ 182 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, 183 unsigned long arg) 184 { 185 struct gendisk *disk = bdev->bd_disk; 186 struct backing_dev_info *bdi; 187 loff_t size; 188 int ret, n; 189 190 switch(cmd) { 191 case BLKFLSBUF: 192 if (!capable(CAP_SYS_ADMIN)) 193 return -EACCES; 194 195 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 196 /* -EINVAL to handle old uncorrected drivers */ 197 if (ret != -EINVAL && ret != -ENOTTY) 198 return ret; 199 200 fsync_bdev(bdev); 201 invalidate_bdev(bdev); 202 return 0; 203 204 case BLKROSET: 205 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 206 /* -EINVAL to handle old uncorrected drivers */ 207 if (ret != -EINVAL && ret != -ENOTTY) 208 return ret; 209 if (!capable(CAP_SYS_ADMIN)) 210 return -EACCES; 211 if (get_user(n, (int __user *)(arg))) 212 return -EFAULT; 213 set_device_ro(bdev, n); 214 return 0; 215 216 case BLKDISCARD: { 217 uint64_t range[2]; 218 219 if (!(mode & FMODE_WRITE)) 220 return -EBADF; 221 222 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 223 return -EFAULT; 224 225 return blk_ioctl_discard(bdev, range[0], range[1]); 226 } 227 228 case HDIO_GETGEO: { 229 struct hd_geometry geo; 230 231 if (!arg) 232 return -EINVAL; 233 if (!disk->fops->getgeo) 234 return -ENOTTY; 235 236 /* 237 * We need to set the startsect first, the driver may 238 * want to override it. 239 */ 240 geo.start = get_start_sect(bdev); 241 ret = disk->fops->getgeo(bdev, &geo); 242 if (ret) 243 return ret; 244 if (copy_to_user((struct hd_geometry __user *)arg, &geo, 245 sizeof(geo))) 246 return -EFAULT; 247 return 0; 248 } 249 case BLKRAGET: 250 case BLKFRAGET: 251 if (!arg) 252 return -EINVAL; 253 bdi = blk_get_backing_dev_info(bdev); 254 if (bdi == NULL) 255 return -ENOTTY; 256 return put_long(arg, (bdi->ra_pages * PAGE_CACHE_SIZE) / 512); 257 case BLKROGET: 258 return put_int(arg, bdev_read_only(bdev) != 0); 259 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */ 260 return put_int(arg, block_size(bdev)); 261 case BLKSSZGET: /* get block device logical block size */ 262 return put_int(arg, bdev_logical_block_size(bdev)); 263 case BLKPBSZGET: /* get block device physical block size */ 264 return put_uint(arg, bdev_physical_block_size(bdev)); 265 case BLKIOMIN: 266 return put_uint(arg, bdev_io_min(bdev)); 267 case BLKIOOPT: 268 return put_uint(arg, bdev_io_opt(bdev)); 269 case BLKALIGNOFF: 270 return put_int(arg, bdev_alignment_offset(bdev)); 271 case BLKDISCARDZEROES: 272 return put_uint(arg, bdev_discard_zeroes_data(bdev)); 273 case BLKSECTGET: 274 return put_ushort(arg, queue_max_sectors(bdev_get_queue(bdev))); 275 case BLKRASET: 276 case BLKFRASET: 277 if(!capable(CAP_SYS_ADMIN)) 278 return -EACCES; 279 bdi = blk_get_backing_dev_info(bdev); 280 if (bdi == NULL) 281 return -ENOTTY; 282 bdi->ra_pages = (arg * 512) / PAGE_CACHE_SIZE; 283 return 0; 284 case BLKBSZSET: 285 /* set the logical block size */ 286 if (!capable(CAP_SYS_ADMIN)) 287 return -EACCES; 288 if (!arg) 289 return -EINVAL; 290 if (get_user(n, (int __user *) arg)) 291 return -EFAULT; 292 if (!(mode & FMODE_EXCL) && bd_claim(bdev, &bdev) < 0) 293 return -EBUSY; 294 ret = set_blocksize(bdev, n); 295 if (!(mode & FMODE_EXCL)) 296 bd_release(bdev); 297 return ret; 298 case BLKPG: 299 ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg); 300 break; 301 case BLKRRPART: 302 ret = blkdev_reread_part(bdev); 303 break; 304 case BLKGETSIZE: 305 size = bdev->bd_inode->i_size; 306 if ((size >> 9) > ~0UL) 307 return -EFBIG; 308 return put_ulong(arg, size >> 9); 309 case BLKGETSIZE64: 310 return put_u64(arg, bdev->bd_inode->i_size); 311 case BLKTRACESTART: 312 case BLKTRACESTOP: 313 case BLKTRACESETUP: 314 case BLKTRACETEARDOWN: 315 ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg); 316 break; 317 default: 318 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 319 } 320 return ret; 321 } 322 EXPORT_SYMBOL_GPL(blkdev_ioctl); 323