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         return 0;
 135 }
 136
 137 /*
 138  * Abort all failfast I/O on a device.
 139  */
 140 static int dasd_ioctl_abortio(struct dasd_block *block)
 141 {
 142         unsigned long flags;
 143         struct dasd_device *base;
 144         struct dasd_ccw_req *cqr, *n;
 145
 146         base = block->base;
 147         if (!capable(CAP_SYS_ADMIN))
 148                 return -EACCES;
 149
 150         if (test_and_set_bit(DASD_FLAG_ABORTALL, &base->flags))
 151                 return 0;
 152         DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag set");
 153
 154         spin_lock_irqsave(&block->request_queue_lock, flags);
 155         spin_lock(&block->queue_lock);
 156         list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
 157                 if (test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
 158                     cqr->callback_data &&
 159                     cqr->callback_data != DASD_SLEEPON_START_TAG &&
 160                     cqr->callback_data != DASD_SLEEPON_END_TAG) {
 161                         spin_unlock(&block->queue_lock);
 162                         blk_abort_request(cqr->callback_data);
 163                         spin_lock(&block->queue_lock);
 164                 }
 165         }
 166         spin_unlock(&block->queue_lock);
 167         spin_unlock_irqrestore(&block->request_queue_lock, flags);
 168
 169         dasd_schedule_block_bh(block);
 170         return 0;
 171 }
 172
 173 /*
 174  * Allow I/O on a device
 175  */
 176 static int dasd_ioctl_allowio(struct dasd_block *block)
 177 {
 178         struct dasd_device *base;
 179
 180         base = block->base;
 181         if (!capable(CAP_SYS_ADMIN))
 182                 return -EACCES;
 183
 184         if (test_and_clear_bit(DASD_FLAG_ABORTALL, &base->flags))
 185                 DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag unset");
 186
 187         return 0;
 188 }
 189
 190 /*
 191  * performs formatting of _device_ according to _fdata_
 192  * Note: The discipline's format_function is assumed to deliver formatting
 193  * commands to format multiple units of the device. In terms of the ECKD
 194  * devices this means CCWs are generated to format multiple tracks.
 195  */
 196 static int
 197 dasd_format(struct dasd_block *block, struct format_data_t *fdata)
 198 {
 199         struct dasd_device *base;
 200         int rc;
 201
 202         base = block->base;
 203         if (base->discipline->format_device == NULL)
 204                 return -EPERM;
 205
 206         if (base->state != DASD_STATE_BASIC) {
 207                 pr_warn("%s: The DASD cannot be formatted while it is enabled\n",
 208                         dev_name(&base->cdev->dev));
 209                 return -EBUSY;
 210         }
 211
 212         DBF_DEV_EVENT(DBF_NOTICE, base,
 213                       "formatting units %u to %u (%u B blocks) flags %u",
 214                       fdata->start_unit,
 215                       fdata->stop_unit, fdata->blksize, fdata->intensity);
 216
 217         /* Since dasdfmt keeps the device open after it was disabled,
 218          * there still exists an inode for this device.
 219          * We must update i_blkbits, otherwise we might get errors when
 220          * enabling the device later.
 221          */
 222         if (fdata->start_unit == 0) {
 223                 struct block_device *bdev = bdget_disk(block->gdp, 0);
 224                 bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
 225                 bdput(bdev);
 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 #ifdef CONFIG_DASD_PROFILE
 384 /*
 385  * Reset device profile information
 386  */
 387 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 388 {
 389         dasd_profile_reset(&block->profile);
 390         return 0;
 391 }
 392
 393 /*
 394  * Return device profile information
 395  */
 396 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 397 {
 398         struct dasd_profile_info_t *data;
 399         int rc = 0;
 400
 401         data = kmalloc(sizeof(*data), GFP_KERNEL);
 402         if (!data)
 403                 return -ENOMEM;
 404
 405         spin_lock_bh(&block->profile.lock);
 406         if (block->profile.data) {
 407                 data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
 408                 data->dasd_io_sects = block->profile.data->dasd_io_sects;
 409                 memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
 410                        sizeof(data->dasd_io_secs));
 411                 memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
 412                        sizeof(data->dasd_io_times));
 413                 memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
 414                        sizeof(data->dasd_io_timps));
 415                 memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
 416                        sizeof(data->dasd_io_time1));
 417                 memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
 418                        sizeof(data->dasd_io_time2));
 419                 memcpy(data->dasd_io_time2ps,
 420                        block->profile.data->dasd_io_time2ps,
 421                        sizeof(data->dasd_io_time2ps));
 422                 memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
 423                        sizeof(data->dasd_io_time3));
 424                 memcpy(data->dasd_io_nr_req,
 425                        block->profile.data->dasd_io_nr_req,
 426                        sizeof(data->dasd_io_nr_req));
 427                 spin_unlock_bh(&block->profile.lock);
 428         } else {
 429                 spin_unlock_bh(&block->profile.lock);
 430                 rc = -EIO;
 431                 goto out;
 432         }
 433         if (copy_to_user(argp, data, sizeof(*data)))
 434                 rc = -EFAULT;
 435 out:
 436         kfree(data);
 437         return rc;
 438 }
 439 #else
 440 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 441 {
 442         return -ENOTTY;
 443 }
 444
 445 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 446 {
 447         return -ENOTTY;
 448 }
 449 #endif
 450
 451 /*
 452  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
 453  */
 454 static int __dasd_ioctl_information(struct dasd_block *block,
 455                 struct dasd_information2_t *dasd_info)
 456 {
 457         struct subchannel_id sch_id;
 458         struct ccw_dev_id dev_id;
 459         struct dasd_device *base;
 460         struct ccw_device *cdev;
 461         struct list_head *l;
 462         unsigned long flags;
 463         int rc;
 464
 465         base = block->base;
 466         if (!base->discipline || !base->discipline->fill_info)
 467                 return -EINVAL;
 468
 469         rc = base->discipline->fill_info(base, dasd_info);
 470         if (rc)
 471                 return rc;
 472
 473         cdev = base->cdev;
 474         ccw_device_get_id(cdev, &dev_id);
 475         ccw_device_get_schid(cdev, &sch_id);
 476
 477         dasd_info->devno = dev_id.devno;
 478         dasd_info->schid = sch_id.sch_no;
 479         dasd_info->cu_type = cdev->id.cu_type;
 480         dasd_info->cu_model = cdev->id.cu_model;
 481         dasd_info->dev_type = cdev->id.dev_type;
 482         dasd_info->dev_model = cdev->id.dev_model;
 483         dasd_info->status = base->state;
 484         /*
 485          * The open_count is increased for every opener, that includes
 486          * the blkdev_get in dasd_scan_partitions.
 487          * This must be hidden from user-space.
 488          */
 489         dasd_info->open_count = atomic_read(&block->open_count);
 490         if (!block->bdev)
 491                 dasd_info->open_count++;
 492
 493         /*
 494          * check if device is really formatted
 495          * LDL / CDL was returned by 'fill_info'
 496          */
 497         if ((base->state < DASD_STATE_READY) ||
 498             (dasd_check_blocksize(block->bp_block)))
 499                 dasd_info->format = DASD_FORMAT_NONE;
 500
 501         dasd_info->features |=
 502                 ((base->features & DASD_FEATURE_READONLY) != 0);
 503
 504         memcpy(dasd_info->type, base->discipline->name, 4);
 505
 506         spin_lock_irqsave(&block->queue_lock, flags);
 507         list_for_each(l, &base->ccw_queue)
 508                 dasd_info->chanq_len++;
 509         spin_unlock_irqrestore(&block->queue_lock, flags);
 510         return 0;
 511 }
 512
 513 static int dasd_ioctl_information(struct dasd_block *block, void __user *argp,
 514                 size_t copy_size)
 515 {
 516         struct dasd_information2_t *dasd_info;
 517         int error;
 518
 519         dasd_info = kzalloc(sizeof(*dasd_info), GFP_KERNEL);
 520         if (!dasd_info)
 521                 return -ENOMEM;
 522
 523         error = __dasd_ioctl_information(block, dasd_info);
 524         if (!error && copy_to_user(argp, dasd_info, copy_size))
 525                 error = -EFAULT;
 526         kfree(dasd_info);
 527         return error;
 528 }
 529
 530 /*
 531  * Set read only
 532  */
 533 int dasd_set_read_only(struct block_device *bdev, bool ro)
 534 {
 535         struct dasd_device *base;
 536         int rc;
 537
 538         /* do not manipulate hardware state for partitions */
 539         if (bdev_is_partition(bdev))
 540                 return 0;
 541
 542         base = dasd_device_from_gendisk(bdev->bd_disk);
 543         if (!base)
 544                 return -ENODEV;
 545         if (!ro && test_bit(DASD_FLAG_DEVICE_RO, &base->flags))
 546                 rc = -EROFS;
 547         else
 548                 rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, ro);
 549         dasd_put_device(base);
 550         return rc;
 551 }
 552
 553 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
 554                                   struct cmbdata __user *argp)
 555 {
 556         size_t size = _IOC_SIZE(cmd);
 557         struct cmbdata data;
 558         int ret;
 559
 560         ret = cmf_readall(block->base->cdev, &data);
 561         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
 562                 return -EFAULT;
 563         return ret;
 564 }
 565
 566 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
 567                unsigned int cmd, unsigned long arg)
 568 {
 569         struct dasd_block *block;
 570         struct dasd_device *base;
 571         void __user *argp;
 572         int rc;
 573
 574         if (is_compat_task())
 575                 argp = compat_ptr(arg);
 576         else
 577                 argp = (void __user *)arg;
 578
 579         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
 580                 PRINT_DEBUG("empty data ptr");
 581                 return -EINVAL;
 582         }
 583
 584         base = dasd_device_from_gendisk(bdev->bd_disk);
 585         if (!base)
 586                 return -ENODEV;
 587         block = base->block;
 588         rc = 0;
 589         switch (cmd) {
 590         case BIODASDDISABLE:
 591                 rc = dasd_ioctl_disable(bdev);
 592                 break;
 593         case BIODASDENABLE:
 594                 rc = dasd_ioctl_enable(bdev);
 595                 break;
 596         case BIODASDQUIESCE:
 597                 rc = dasd_ioctl_quiesce(block);
 598                 break;
 599         case BIODASDRESUME:
 600                 rc = dasd_ioctl_resume(block);
 601                 break;
 602         case BIODASDABORTIO:
 603                 rc = dasd_ioctl_abortio(block);
 604                 break;
 605         case BIODASDALLOWIO:
 606                 rc = dasd_ioctl_allowio(block);
 607                 break;
 608         case BIODASDFMT:
 609                 rc = dasd_ioctl_format(bdev, argp);
 610                 break;
 611         case BIODASDCHECKFMT:
 612                 rc = dasd_ioctl_check_format(bdev, argp);
 613                 break;
 614         case BIODASDINFO:
 615                 rc = dasd_ioctl_information(block, argp,
 616                                 sizeof(struct dasd_information_t));
 617                 break;
 618         case BIODASDINFO2:
 619                 rc = dasd_ioctl_information(block, argp,
 620                                 sizeof(struct dasd_information2_t));
 621                 break;
 622         case BIODASDPRRD:
 623                 rc = dasd_ioctl_read_profile(block, argp);
 624                 break;
 625         case BIODASDPRRST:
 626                 rc = dasd_ioctl_reset_profile(block);
 627                 break;
 628         case DASDAPIVER:
 629                 rc = dasd_ioctl_api_version(argp);
 630                 break;
 631         case BIODASDCMFENABLE:
 632                 rc = enable_cmf(base->cdev);
 633                 break;
 634         case BIODASDCMFDISABLE:
 635                 rc = disable_cmf(base->cdev);
 636                 break;
 637         case BIODASDREADALLCMB:
 638                 rc = dasd_ioctl_readall_cmb(block, cmd, argp);
 639                 break;
 640         case BIODASDRAS:
 641                 rc = dasd_ioctl_release_space(bdev, argp);
 642                 break;
 643         default:
 644                 /* if the discipline has an ioctl method try it. */
 645                 rc = -ENOTTY;
 646                 if (base->discipline->ioctl)
 647                         rc = base->discipline->ioctl(block, cmd, argp);
 648         }
 649         dasd_put_device(base);
 650         return rc;
 651 }
 652
 653
 654 /**
 655  * dasd_biodasdinfo() - fill out the dasd information structure
 656  * @disk [in]: pointer to gendisk structure that references a DASD
 657  * @info [out]: pointer to the dasd_information2_t structure
 658  *
 659  * Provide access to DASD specific information.
 660  * The gendisk structure is checked if it belongs to the DASD driver by
 661  * comparing the gendisk->fops pointer.
 662  * If it does not belong to the DASD driver -EINVAL is returned.
 663  * Otherwise the provided dasd_information2_t structure is filled out.
 664  *
 665  * Returns:
 666  *   %0 on success and a negative error value on failure.
 667  */
 668 int dasd_biodasdinfo(struct gendisk *disk, struct dasd_information2_t *info)
 669 {
 670         struct dasd_device *base;
 671         int error;
 672
 673         if (disk->fops != &dasd_device_operations)
 674                 return -EINVAL;
 675
 676         base = dasd_device_from_gendisk(disk);
 677         if (!base)
 678                 return -ENODEV;
 679         error = __dasd_ioctl_information(base->block, info);
 680         dasd_put_device(base);
 681         return error;
 682 }
 683 /* export that symbol_get in partition detection is possible */
 684 EXPORT_SYMBOL_GPL(dasd_biodasdinfo);