| 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); |