drivers/s390/block/dasd_ioctl.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   4  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
   5  *                  Carsten Otte <Cotte@de.ibm.com>
   6  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
   7  * Bugreports.to..: <Linux390@de.ibm.com>
   8  * Copyright IBM Corp. 1999, 2001
   9  *
  10  * i/o controls for the dasd driver.
  11  */
  12
  13 #define KMSG_COMPONENT "dasd"
  14
  15 #include <linux/interrupt.h>
  16 #include <linux/compat.h>
  17 #include <linux/major.h>
  18 #include <linux/fs.h>
  19 #include <linux/blkpg.h>
  20 #include <linux/slab.h>
  21 #include <asm/ccwdev.h>
  22 #include <asm/schid.h>
  23 #include <asm/cmb.h>
  24 #include <linux/uaccess.h>
  25 #include <linux/dasd_mod.h>
  26
  27 /* This is ugly... */
  28 #define PRINTK_HEADER "dasd_ioctl:"
  29
  30 #include "dasd_int.h"
  31
  32
  33 static int
  34 dasd_ioctl_api_version(void __user *argp)
  35 {
  36         int ver = DASD_API_VERSION;
  37         return put_user(ver, (int __user *)argp);
  38 }
  39
  40 /*
  41  * Enable device.
  42  * used by dasdfmt after BIODASDDISABLE to retrigger blocksize detection
  43  */
  44 static int
  45 dasd_ioctl_enable(struct block_device *bdev)
  46 {
  47         struct dasd_device *base;
  48
  49         if (!capable(CAP_SYS_ADMIN))
  50                 return -EACCES;
  51
  52         base = dasd_device_from_gendisk(bdev->bd_disk);
  53         if (!base)
  54                 return -ENODEV;
  55
  56         dasd_enable_device(base);
  57         dasd_put_device(base);
  58         return 0;
  59 }
  60
  61 /*
  62  * Disable device.
  63  * Used by dasdfmt. Disable I/O operations but allow ioctls.
  64  */
  65 static int
  66 dasd_ioctl_disable(struct block_device *bdev)
  67 {
  68         struct dasd_device *base;
  69
  70         if (!capable(CAP_SYS_ADMIN))
  71                 return -EACCES;
  72
  73         base = dasd_device_from_gendisk(bdev->bd_disk);
  74         if (!base)
  75                 return -ENODEV;
  76         /*
  77          * Man this is sick. We don't do a real disable but only downgrade
  78          * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
  79          * BIODASDDISABLE to disable accesses to the device via the block
  80          * device layer but it still wants to do i/o on the device by
  81          * using the BIODASDFMT ioctl. Therefore the correct state for the
  82          * device is DASD_STATE_BASIC that allows to do basic i/o.
  83          */
  84         dasd_set_target_state(base, DASD_STATE_BASIC);
  85         /*
  86          * Set i_size to zero, since read, write, etc. check against this
  87          * value.
  88          */
  89         set_capacity(bdev->bd_disk, 0);
  90         dasd_put_device(base);
  91         return 0;
  92 }
  93
  94 /*
  95  * Quiesce device.
  96  */
  97 static int dasd_ioctl_quiesce(struct dasd_block *block)
  98 {
  99         unsigned long flags;
 100         struct dasd_device *base;
 101
 102         base = block->base;
 103         if (!capable (CAP_SYS_ADMIN))
 104                 return -EACCES;
 105
 106         pr_info("%s: The DASD has been put in the quiesce "
 107                 "state\n", dev_name(&base->cdev->dev));
 108         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 109         dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
 110         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 111         return 0;
 112 }
 113
 114
 115 /*
 116  * Resume device.
 117  */
 118 static int dasd_ioctl_resume(struct dasd_block *block)
 119 {
 120         unsigned long flags;
 121         struct dasd_device *base;
 122
 123         base = block->base;
 124         if (!capable (CAP_SYS_ADMIN))
 125                 return -EACCES;
 126
 127         pr_info("%s: I/O operations have been resumed "
 128                 "on the DASD\n", dev_name(&base->cdev->dev));
 129         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 130         dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
 131         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 132
 133         dasd_schedule_block_bh(block);
 134         dasd_schedule_device_bh(base);
 135         return 0;
 136 }
 137
 138 /*
 139  * Abort all failfast I/O on a device.
 140  */
 141 static int dasd_ioctl_abortio(struct dasd_block *block)
 142 {
 143         unsigned long flags;
 144         struct dasd_device *base;
 145         struct dasd_ccw_req *cqr, *n;
 146
 147         base = block->base;
 148         if (!capable(CAP_SYS_ADMIN))
 149                 return -EACCES;
 150
 151         if (test_and_set_bit(DASD_FLAG_ABORTALL, &base->flags))
 152                 return 0;
 153         DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag set");
 154
 155         spin_lock_irqsave(&block->request_queue_lock, flags);
 156         spin_lock(&block->queue_lock);
 157         list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
 158                 if (test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
 159                     cqr->callback_data &&
 160                     cqr->callback_data != DASD_SLEEPON_START_TAG &&
 161                     cqr->callback_data != DASD_SLEEPON_END_TAG) {
 162                         spin_unlock(&block->queue_lock);
 163                         blk_abort_request(cqr->callback_data);
 164                         spin_lock(&block->queue_lock);
 165                 }
 166         }
 167         spin_unlock(&block->queue_lock);
 168         spin_unlock_irqrestore(&block->request_queue_lock, flags);
 169
 170         dasd_schedule_block_bh(block);
 171         return 0;
 172 }
 173
 174 /*
 175  * Allow I/O on a device
 176  */
 177 static int dasd_ioctl_allowio(struct dasd_block *block)
 178 {
 179         struct dasd_device *base;
 180
 181         base = block->base;
 182         if (!capable(CAP_SYS_ADMIN))
 183                 return -EACCES;
 184
 185         if (test_and_clear_bit(DASD_FLAG_ABORTALL, &base->flags))
 186                 DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag unset");
 187
 188         return 0;
 189 }
 190
 191 /*
 192  * performs formatting of _device_ according to _fdata_
 193  * Note: The discipline's format_function is assumed to deliver formatting
 194  * commands to format multiple units of the device. In terms of the ECKD
 195  * devices this means CCWs are generated to format multiple tracks.
 196  */
 197 static int
 198 dasd_format(struct dasd_block *block, struct format_data_t *fdata)
 199 {
 200         struct dasd_device *base;
 201         int rc;
 202
 203         base = block->base;
 204         if (base->discipline->format_device == NULL)
 205                 return -EPERM;
 206
 207         if (base->state != DASD_STATE_BASIC) {
 208                 pr_warn("%s: The DASD cannot be formatted while it is enabled\n",
 209                         dev_name(&base->cdev->dev));
 210                 return -EBUSY;
 211         }
 212
 213         DBF_DEV_EVENT(DBF_NOTICE, base,
 214                       "formatting units %u to %u (%u B blocks) flags %u",
 215                       fdata->start_unit,
 216                       fdata->stop_unit, fdata->blksize, fdata->intensity);
 217
 218         /* Since dasdfmt keeps the device open after it was disabled,
 219          * there still exists an inode for this device.
 220          * We must update i_blkbits, otherwise we might get errors when
 221          * enabling the device later.
 222          */
 223         if (fdata->start_unit == 0) {
 224                 block->gdp->part0->bd_inode->i_blkbits =
 225                         blksize_bits(fdata->blksize);
 226         }
 227
 228         rc = base->discipline->format_device(base, fdata, 1);
 229         if (rc == -EAGAIN)
 230                 rc = base->discipline->format_device(base, fdata, 0);
 231
 232         return rc;
 233 }
 234
 235 static int dasd_check_format(struct dasd_block *block,
 236                              struct format_check_t *cdata)
 237 {
 238         struct dasd_device *base;
 239         int rc;
 240
 241         base = block->base;
 242         if (!base->discipline->check_device_format)
 243                 return -ENOTTY;
 244
 245         rc = base->discipline->check_device_format(base, cdata, 1);
 246         if (rc == -EAGAIN)
 247                 rc = base->discipline->check_device_format(base, cdata, 0);
 248
 249         return rc;
 250 }
 251
 252 /*
 253  * Format device.
 254  */
 255 static int
 256 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
 257 {
 258         struct dasd_device *base;
 259         struct format_data_t fdata;
 260         int rc;
 261
 262         if (!capable(CAP_SYS_ADMIN))
 263                 return -EACCES;
 264         if (!argp)
 265                 return -EINVAL;
 266         base = dasd_device_from_gendisk(bdev->bd_disk);
 267         if (!base)
 268                 return -ENODEV;
 269         if (base->features & DASD_FEATURE_READONLY ||
 270             test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 271                 dasd_put_device(base);
 272                 return -EROFS;
 273         }
 274         if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
 275                 dasd_put_device(base);
 276                 return -EFAULT;
 277         }
 278         if (bdev_is_partition(bdev)) {
 279                 pr_warn("%s: The specified DASD is a partition and cannot be formatted\n",
 280                         dev_name(&base->cdev->dev));
 281                 dasd_put_device(base);
 282                 return -EINVAL;
 283         }
 284         rc = dasd_format(base->block, &fdata);
 285         dasd_put_device(base);
 286
 287         return rc;
 288 }
 289
 290 /*
 291  * Check device format
 292  */
 293 static int dasd_ioctl_check_format(struct block_device *bdev, void __user *argp)
 294 {
 295         struct format_check_t cdata;
 296         struct dasd_device *base;
 297         int rc = 0;
 298
 299         if (!argp)
 300                 return -EINVAL;
 301
 302         base = dasd_device_from_gendisk(bdev->bd_disk);
 303         if (!base)
 304                 return -ENODEV;
 305         if (bdev_is_partition(bdev)) {
 306                 pr_warn("%s: The specified DASD is a partition and cannot be checked\n",
 307                         dev_name(&base->cdev->dev));
 308                 rc = -EINVAL;
 309                 goto out_err;
 310         }
 311
 312         if (copy_from_user(&cdata, argp, sizeof(cdata))) {
 313                 rc = -EFAULT;
 314                 goto out_err;
 315         }
 316
 317         rc = dasd_check_format(base->block, &cdata);
 318         if (rc)
 319                 goto out_err;
 320
 321         if (copy_to_user(argp, &cdata, sizeof(cdata)))
 322                 rc = -EFAULT;
 323
 324 out_err:
 325         dasd_put_device(base);
 326
 327         return rc;
 328 }
 329
 330 static int dasd_release_space(struct dasd_device *device,
 331                               struct format_data_t *rdata)
 332 {
 333         if (!device->discipline->is_ese && !device->discipline->is_ese(device))
 334                 return -ENOTSUPP;
 335         if (!device->discipline->release_space)
 336                 return -ENOTSUPP;
 337
 338         return device->discipline->release_space(device, rdata);
 339 }
 340
 341 /*
 342  * Release allocated space
 343  */
 344 static int dasd_ioctl_release_space(struct block_device *bdev, void __user *argp)
 345 {
 346         struct format_data_t rdata;
 347         struct dasd_device *base;
 348         int rc = 0;
 349
 350         if (!capable(CAP_SYS_ADMIN))
 351                 return -EACCES;
 352         if (!argp)
 353                 return -EINVAL;
 354
 355         base = dasd_device_from_gendisk(bdev->bd_disk);
 356         if (!base)
 357                 return -ENODEV;
 358         if (base->features & DASD_FEATURE_READONLY ||
 359             test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 360                 rc = -EROFS;
 361                 goto out_err;
 362         }
 363         if (bdev_is_partition(bdev)) {
 364                 pr_warn("%s: The specified DASD is a partition and tracks cannot be released\n",
 365                         dev_name(&base->cdev->dev));
 366                 rc = -EINVAL;
 367                 goto out_err;
 368         }
 369
 370         if (copy_from_user(&rdata, argp, sizeof(rdata))) {
 371                 rc = -EFAULT;
 372                 goto out_err;
 373         }
 374
 375         rc = dasd_release_space(base, &rdata);
 376
 377 out_err:
 378         dasd_put_device(base);
 379
 380         return rc;
 381 }
 382
 383 /*
 384  * Swap driver iternal copy relation.
 385  */
 386 static int
 387 dasd_ioctl_copy_pair_swap(struct block_device *bdev, void __user *argp)
 388 {
 389         struct dasd_copypair_swap_data_t data;
 390         struct dasd_device *device;
 391         int rc;
 392
 393         if (!capable(CAP_SYS_ADMIN))
 394                 return -EACCES;
 395
 396         device = dasd_device_from_gendisk(bdev->bd_disk);
 397         if (!device)
 398                 return -ENODEV;
 399
 400         if (copy_from_user(&data, argp, sizeof(struct dasd_copypair_swap_data_t))) {
 401                 dasd_put_device(device);
 402                 return -EFAULT;
 403         }
 404         if (memchr_inv(data.reserved, 0, sizeof(data.reserved))) {
 405                 pr_warn("%s: Invalid swap data specified\n",
 406                         dev_name(&device->cdev->dev));
 407                 dasd_put_device(device);
 408                 return DASD_COPYPAIRSWAP_INVALID;
 409         }
 410         if (bdev_is_partition(bdev)) {
 411                 pr_warn("%s: The specified DASD is a partition and cannot be swapped\n",
 412                         dev_name(&device->cdev->dev));
 413                 dasd_put_device(device);
 414                 return DASD_COPYPAIRSWAP_INVALID;
 415         }
 416         if (!device->copy) {
 417                 pr_warn("%s: The specified DASD has no copy pair set up\n",
 418                         dev_name(&device->cdev->dev));
 419                 dasd_put_device(device);
 420                 return -ENODEV;
 421         }
 422         if (!device->discipline->copy_pair_swap) {
 423                 dasd_put_device(device);
 424                 return -EOPNOTSUPP;
 425         }
 426         rc = device->discipline->copy_pair_swap(device, data.primary,
 427                                                 data.secondary);
 428         dasd_put_device(device);
 429
 430         return rc;
 431 }
 432
 433 #ifdef CONFIG_DASD_PROFILE
 434 /*
 435  * Reset device profile information
 436  */
 437 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 438 {
 439         dasd_profile_reset(&block->profile);
 440         return 0;
 441 }
 442
 443 /*
 444  * Return device profile information
 445  */
 446 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 447 {
 448         struct dasd_profile_info_t *data;
 449         int rc = 0;
 450
 451         data = kmalloc(sizeof(*data), GFP_KERNEL);
 452         if (!data)
 453                 return -ENOMEM;
 454
 455         spin_lock_bh(&block->profile.lock);
 456         if (block->profile.data) {
 457                 data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
 458                 data->dasd_io_sects = block->profile.data->dasd_io_sects;
 459                 memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
 460                        sizeof(data->dasd_io_secs));
 461                 memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
 462                        sizeof(data->dasd_io_times));
 463                 memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
 464                        sizeof(data->dasd_io_timps));
 465                 memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
 466                        sizeof(data->dasd_io_time1));
 467                 memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
 468                        sizeof(data->dasd_io_time2));
 469                 memcpy(data->dasd_io_time2ps,
 470                        block->profile.data->dasd_io_time2ps,
 471                        sizeof(data->dasd_io_time2ps));
 472                 memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
 473                        sizeof(data->dasd_io_time3));
 474                 memcpy(data->dasd_io_nr_req,
 475                        block->profile.data->dasd_io_nr_req,
 476                        sizeof(data->dasd_io_nr_req));
 477                 spin_unlock_bh(&block->profile.lock);
 478         } else {
 479                 spin_unlock_bh(&block->profile.lock);
 480                 rc = -EIO;
 481                 goto out;
 482         }
 483         if (copy_to_user(argp, data, sizeof(*data)))
 484                 rc = -EFAULT;
 485 out:
 486         kfree(data);
 487         return rc;
 488 }
 489 #else
 490 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 491 {
 492         return -ENOTTY;
 493 }
 494
 495 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 496 {
 497         return -ENOTTY;
 498 }
 499 #endif
 500
 501 /*
 502  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
 503  */
 504 static int __dasd_ioctl_information(struct dasd_block *block,
 505                 struct dasd_information2_t *dasd_info)
 506 {
 507         struct subchannel_id sch_id;
 508         struct ccw_dev_id dev_id;
 509         struct dasd_device *base;
 510         struct ccw_device *cdev;
 511         struct list_head *l;
 512         unsigned long flags;
 513         int rc;
 514
 515         base = block->base;
 516         if (!base->discipline || !base->discipline->fill_info)
 517                 return -EINVAL;
 518
 519         rc = base->discipline->fill_info(base, dasd_info);
 520         if (rc)
 521                 return rc;
 522
 523         cdev = base->cdev;
 524         ccw_device_get_id(cdev, &dev_id);
 525         ccw_device_get_schid(cdev, &sch_id);
 526
 527         dasd_info->devno = dev_id.devno;
 528         dasd_info->schid = sch_id.sch_no;
 529         dasd_info->cu_type = cdev->id.cu_type;
 530         dasd_info->cu_model = cdev->id.cu_model;
 531         dasd_info->dev_type = cdev->id.dev_type;
 532         dasd_info->dev_model = cdev->id.dev_model;
 533         dasd_info->status = base->state;
 534         /*
 535          * The open_count is increased for every opener, that includes
 536          * the blkdev_get in dasd_scan_partitions.
 537          * This must be hidden from user-space.
 538          */
 539         dasd_info->open_count = atomic_read(&block->open_count);
 540         if (!block->bdev)
 541                 dasd_info->open_count++;
 542
 543         /*
 544          * check if device is really formatted
 545          * LDL / CDL was returned by 'fill_info'
 546          */
 547         if ((base->state < DASD_STATE_READY) ||
 548             (dasd_check_blocksize(block->bp_block)))
 549                 dasd_info->format = DASD_FORMAT_NONE;
 550
 551         dasd_info->features |=
 552                 ((base->features & DASD_FEATURE_READONLY) != 0);
 553
 554         memcpy(dasd_info->type, base->discipline->name, 4);
 555
 556         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 557         list_for_each(l, &base->ccw_queue)
 558                 dasd_info->chanq_len++;
 559         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 560         return 0;
 561 }
 562
 563 static int dasd_ioctl_information(struct dasd_block *block, void __user *argp,
 564                 size_t copy_size)
 565 {
 566         struct dasd_information2_t *dasd_info;
 567         int error;
 568
 569         dasd_info = kzalloc(sizeof(*dasd_info), GFP_KERNEL);
 570         if (!dasd_info)
 571                 return -ENOMEM;
 572
 573         error = __dasd_ioctl_information(block, dasd_info);
 574         if (!error && copy_to_user(argp, dasd_info, copy_size))
 575                 error = -EFAULT;
 576         kfree(dasd_info);
 577         return error;
 578 }
 579
 580 /*
 581  * Set read only
 582  */
 583 int dasd_set_read_only(struct block_device *bdev, bool ro)
 584 {
 585         struct dasd_device *base;
 586         int rc;
 587
 588         /* do not manipulate hardware state for partitions */
 589         if (bdev_is_partition(bdev))
 590                 return 0;
 591
 592         base = dasd_device_from_gendisk(bdev->bd_disk);
 593         if (!base)
 594                 return -ENODEV;
 595         if (!ro && test_bit(DASD_FLAG_DEVICE_RO, &base->flags))
 596                 rc = -EROFS;
 597         else
 598                 rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, ro);
 599         dasd_put_device(base);
 600         return rc;
 601 }
 602
 603 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
 604                                   struct cmbdata __user *argp)
 605 {
 606         size_t size = _IOC_SIZE(cmd);
 607         struct cmbdata data;
 608         int ret;
 609
 610         ret = cmf_readall(block->base->cdev, &data);
 611         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
 612                 return -EFAULT;
 613         return ret;
 614 }
 615
 616 int dasd_ioctl(struct block_device *bdev, blk_mode_t mode,
 617                unsigned int cmd, unsigned long arg)
 618 {
 619         struct dasd_block *block;
 620         struct dasd_device *base;
 621         void __user *argp;
 622         int rc;
 623
 624         if (is_compat_task())
 625                 argp = compat_ptr(arg);
 626         else
 627                 argp = (void __user *)arg;
 628
 629         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg)
 630                 return -EINVAL;
 631
 632         base = dasd_device_from_gendisk(bdev->bd_disk);
 633         if (!base)
 634                 return -ENODEV;
 635         block = base->block;
 636         rc = 0;
 637         switch (cmd) {
 638         case BIODASDDISABLE:
 639                 rc = dasd_ioctl_disable(bdev);
 640                 break;
 641         case BIODASDENABLE:
 642                 rc = dasd_ioctl_enable(bdev);
 643                 break;
 644         case BIODASDQUIESCE:
 645                 rc = dasd_ioctl_quiesce(block);
 646                 break;
 647         case BIODASDRESUME:
 648                 rc = dasd_ioctl_resume(block);
 649                 break;
 650         case BIODASDABORTIO:
 651                 rc = dasd_ioctl_abortio(block);
 652                 break;
 653         case BIODASDALLOWIO:
 654                 rc = dasd_ioctl_allowio(block);
 655                 break;
 656         case BIODASDFMT:
 657                 rc = dasd_ioctl_format(bdev, argp);
 658                 break;
 659         case BIODASDCHECKFMT:
 660                 rc = dasd_ioctl_check_format(bdev, argp);
 661                 break;
 662         case BIODASDINFO:
 663                 rc = dasd_ioctl_information(block, argp,
 664                                 sizeof(struct dasd_information_t));
 665                 break;
 666         case BIODASDINFO2:
 667                 rc = dasd_ioctl_information(block, argp,
 668                                 sizeof(struct dasd_information2_t));
 669                 break;
 670         case BIODASDPRRD:
 671                 rc = dasd_ioctl_read_profile(block, argp);
 672                 break;
 673         case BIODASDPRRST:
 674                 rc = dasd_ioctl_reset_profile(block);
 675                 break;
 676         case DASDAPIVER:
 677                 rc = dasd_ioctl_api_version(argp);
 678                 break;
 679         case BIODASDCMFENABLE:
 680                 rc = enable_cmf(base->cdev);
 681                 break;
 682         case BIODASDCMFDISABLE:
 683                 rc = disable_cmf(base->cdev);
 684                 break;
 685         case BIODASDREADALLCMB:
 686                 rc = dasd_ioctl_readall_cmb(block, cmd, argp);
 687                 break;
 688         case BIODASDRAS:
 689                 rc = dasd_ioctl_release_space(bdev, argp);
 690                 break;
 691         case BIODASDCOPYPAIRSWAP:
 692                 rc = dasd_ioctl_copy_pair_swap(bdev, argp);
 693                 break;
 694         default:
 695                 /* if the discipline has an ioctl method try it. */
 696                 rc = -ENOTTY;
 697                 if (base->discipline->ioctl)
 698                         rc = base->discipline->ioctl(block, cmd, argp);
 699         }
 700         dasd_put_device(base);
 701         return rc;
 702 }
 703
 704
 705 /**
 706  * dasd_biodasdinfo() - fill out the dasd information structure
 707  * @disk: [in] pointer to gendisk structure that references a DASD
 708  * @info: [out] pointer to the dasd_information2_t structure
 709  *
 710  * Provide access to DASD specific information.
 711  * The gendisk structure is checked if it belongs to the DASD driver by
 712  * comparing the gendisk->fops pointer.
 713  * If it does not belong to the DASD driver -EINVAL is returned.
 714  * Otherwise the provided dasd_information2_t structure is filled out.
 715  *
 716  * Returns:
 717  *   %0 on success and a negative error value on failure.
 718  */
 719 int dasd_biodasdinfo(struct gendisk *disk, struct dasd_information2_t *info)
 720 {
 721         struct dasd_device *base;
 722         int error;
 723
 724         if (disk->fops != &dasd_device_operations)
 725                 return -EINVAL;
 726
 727         base = dasd_device_from_gendisk(disk);
 728         if (!base)
 729                 return -ENODEV;
 730         error = __dasd_ioctl_information(base->block, info);
 731         dasd_put_device(base);
 732         return error;
 733 }
 734 /* export that symbol_get in partition detection is possible */
 735 EXPORT_SYMBOL_GPL(dasd_biodasdinfo);