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/compat.h>
  22 #include <asm/ccwdev.h>
  23 #include <asm/schid.h>
  24 #include <asm/cmb.h>
  25 #include <linux/uaccess.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         /* Formatting the dasd device can change the capacity. */
  58         mutex_lock(&bdev->bd_mutex);
  59         i_size_write(bdev->bd_inode,
  60                      (loff_t)get_capacity(base->block->gdp) << 9);
  61         mutex_unlock(&bdev->bd_mutex);
  62         dasd_put_device(base);
  63         return 0;
  64 }
  65
  66 /*
  67  * Disable device.
  68  * Used by dasdfmt. Disable I/O operations but allow ioctls.
  69  */
  70 static int
  71 dasd_ioctl_disable(struct block_device *bdev)
  72 {
  73         struct dasd_device *base;
  74
  75         if (!capable(CAP_SYS_ADMIN))
  76                 return -EACCES;
  77
  78         base = dasd_device_from_gendisk(bdev->bd_disk);
  79         if (!base)
  80                 return -ENODEV;
  81         /*
  82          * Man this is sick. We don't do a real disable but only downgrade
  83          * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
  84          * BIODASDDISABLE to disable accesses to the device via the block
  85          * device layer but it still wants to do i/o on the device by
  86          * using the BIODASDFMT ioctl. Therefore the correct state for the
  87          * device is DASD_STATE_BASIC that allows to do basic i/o.
  88          */
  89         dasd_set_target_state(base, DASD_STATE_BASIC);
  90         /*
  91          * Set i_size to zero, since read, write, etc. check against this
  92          * value.
  93          */
  94         mutex_lock(&bdev->bd_mutex);
  95         i_size_write(bdev->bd_inode, 0);
  96         mutex_unlock(&bdev->bd_mutex);
  97         dasd_put_device(base);
  98         return 0;
  99 }
 100
 101 /*
 102  * Quiesce device.
 103  */
 104 static int dasd_ioctl_quiesce(struct dasd_block *block)
 105 {
 106         unsigned long flags;
 107         struct dasd_device *base;
 108
 109         base = block->base;
 110         if (!capable (CAP_SYS_ADMIN))
 111                 return -EACCES;
 112
 113         pr_info("%s: The DASD has been put in the quiesce "
 114                 "state\n", dev_name(&base->cdev->dev));
 115         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 116         dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
 117         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 118         return 0;
 119 }
 120
 121
 122 /*
 123  * Resume device.
 124  */
 125 static int dasd_ioctl_resume(struct dasd_block *block)
 126 {
 127         unsigned long flags;
 128         struct dasd_device *base;
 129
 130         base = block->base;
 131         if (!capable (CAP_SYS_ADMIN))
 132                 return -EACCES;
 133
 134         pr_info("%s: I/O operations have been resumed "
 135                 "on the DASD\n", dev_name(&base->cdev->dev));
 136         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 137         dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
 138         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 139
 140         dasd_schedule_block_bh(block);
 141         return 0;
 142 }
 143
 144 /*
 145  * Abort all failfast I/O on a device.
 146  */
 147 static int dasd_ioctl_abortio(struct dasd_block *block)
 148 {
 149         unsigned long flags;
 150         struct dasd_device *base;
 151         struct dasd_ccw_req *cqr, *n;
 152
 153         base = block->base;
 154         if (!capable(CAP_SYS_ADMIN))
 155                 return -EACCES;
 156
 157         if (test_and_set_bit(DASD_FLAG_ABORTALL, &base->flags))
 158                 return 0;
 159         DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag set");
 160
 161         spin_lock_irqsave(&block->request_queue_lock, flags);
 162         spin_lock(&block->queue_lock);
 163         list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
 164                 if (test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
 165                     cqr->callback_data &&
 166                     cqr->callback_data != DASD_SLEEPON_START_TAG &&
 167                     cqr->callback_data != DASD_SLEEPON_END_TAG) {
 168                         spin_unlock(&block->queue_lock);
 169                         blk_abort_request(cqr->callback_data);
 170                         spin_lock(&block->queue_lock);
 171                 }
 172         }
 173         spin_unlock(&block->queue_lock);
 174         spin_unlock_irqrestore(&block->request_queue_lock, flags);
 175
 176         dasd_schedule_block_bh(block);
 177         return 0;
 178 }
 179
 180 /*
 181  * Allow I/O on a device
 182  */
 183 static int dasd_ioctl_allowio(struct dasd_block *block)
 184 {
 185         struct dasd_device *base;
 186
 187         base = block->base;
 188         if (!capable(CAP_SYS_ADMIN))
 189                 return -EACCES;
 190
 191         if (test_and_clear_bit(DASD_FLAG_ABORTALL, &base->flags))
 192                 DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag unset");
 193
 194         return 0;
 195 }
 196
 197 /*
 198  * performs formatting of _device_ according to _fdata_
 199  * Note: The discipline's format_function is assumed to deliver formatting
 200  * commands to format multiple units of the device. In terms of the ECKD
 201  * devices this means CCWs are generated to format multiple tracks.
 202  */
 203 static int
 204 dasd_format(struct dasd_block *block, struct format_data_t *fdata)
 205 {
 206         struct dasd_device *base;
 207         int rc;
 208
 209         base = block->base;
 210         if (base->discipline->format_device == NULL)
 211                 return -EPERM;
 212
 213         if (base->state != DASD_STATE_BASIC) {
 214                 pr_warn("%s: The DASD cannot be formatted while it is enabled\n",
 215                         dev_name(&base->cdev->dev));
 216                 return -EBUSY;
 217         }
 218
 219         DBF_DEV_EVENT(DBF_NOTICE, base,
 220                       "formatting units %u to %u (%u B blocks) flags %u",
 221                       fdata->start_unit,
 222                       fdata->stop_unit, fdata->blksize, fdata->intensity);
 223
 224         /* Since dasdfmt keeps the device open after it was disabled,
 225          * there still exists an inode for this device.
 226          * We must update i_blkbits, otherwise we might get errors when
 227          * enabling the device later.
 228          */
 229         if (fdata->start_unit == 0) {
 230                 struct block_device *bdev = bdget_disk(block->gdp, 0);
 231                 bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
 232                 bdput(bdev);
 233         }
 234
 235         rc = base->discipline->format_device(base, fdata, 1);
 236         if (rc == -EAGAIN)
 237                 rc = base->discipline->format_device(base, fdata, 0);
 238
 239         return rc;
 240 }
 241
 242 static int dasd_check_format(struct dasd_block *block,
 243                              struct format_check_t *cdata)
 244 {
 245         struct dasd_device *base;
 246         int rc;
 247
 248         base = block->base;
 249         if (!base->discipline->check_device_format)
 250                 return -ENOTTY;
 251
 252         rc = base->discipline->check_device_format(base, cdata, 1);
 253         if (rc == -EAGAIN)
 254                 rc = base->discipline->check_device_format(base, cdata, 0);
 255
 256         return rc;
 257 }
 258
 259 /*
 260  * Format device.
 261  */
 262 static int
 263 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
 264 {
 265         struct dasd_device *base;
 266         struct format_data_t fdata;
 267         int rc;
 268
 269         if (!capable(CAP_SYS_ADMIN))
 270                 return -EACCES;
 271         if (!argp)
 272                 return -EINVAL;
 273         base = dasd_device_from_gendisk(bdev->bd_disk);
 274         if (!base)
 275                 return -ENODEV;
 276         if (base->features & DASD_FEATURE_READONLY ||
 277             test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 278                 dasd_put_device(base);
 279                 return -EROFS;
 280         }
 281         if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
 282                 dasd_put_device(base);
 283                 return -EFAULT;
 284         }
 285         if (bdev != bdev->bd_contains) {
 286                 pr_warn("%s: The specified DASD is a partition and cannot be formatted\n",
 287                         dev_name(&base->cdev->dev));
 288                 dasd_put_device(base);
 289                 return -EINVAL;
 290         }
 291         rc = dasd_format(base->block, &fdata);
 292         dasd_put_device(base);
 293
 294         return rc;
 295 }
 296
 297 /*
 298  * Check device format
 299  */
 300 static int dasd_ioctl_check_format(struct block_device *bdev, void __user *argp)
 301 {
 302         struct format_check_t cdata;
 303         struct dasd_device *base;
 304         int rc = 0;
 305
 306         if (!argp)
 307                 return -EINVAL;
 308
 309         base = dasd_device_from_gendisk(bdev->bd_disk);
 310         if (!base)
 311                 return -ENODEV;
 312         if (bdev != bdev->bd_contains) {
 313                 pr_warn("%s: The specified DASD is a partition and cannot be checked\n",
 314                         dev_name(&base->cdev->dev));
 315                 rc = -EINVAL;
 316                 goto out_err;
 317         }
 318
 319         if (copy_from_user(&cdata, argp, sizeof(cdata))) {
 320                 rc = -EFAULT;
 321                 goto out_err;
 322         }
 323
 324         rc = dasd_check_format(base->block, &cdata);
 325         if (rc)
 326                 goto out_err;
 327
 328         if (copy_to_user(argp, &cdata, sizeof(cdata)))
 329                 rc = -EFAULT;
 330
 331 out_err:
 332         dasd_put_device(base);
 333
 334         return rc;
 335 }
 336
 337 #ifdef CONFIG_DASD_PROFILE
 338 /*
 339  * Reset device profile information
 340  */
 341 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 342 {
 343         dasd_profile_reset(&block->profile);
 344         return 0;
 345 }
 346
 347 /*
 348  * Return device profile information
 349  */
 350 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 351 {
 352         struct dasd_profile_info_t *data;
 353         int rc = 0;
 354
 355         data = kmalloc(sizeof(*data), GFP_KERNEL);
 356         if (!data)
 357                 return -ENOMEM;
 358
 359         spin_lock_bh(&block->profile.lock);
 360         if (block->profile.data) {
 361                 data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
 362                 data->dasd_io_sects = block->profile.data->dasd_io_sects;
 363                 memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
 364                        sizeof(data->dasd_io_secs));
 365                 memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
 366                        sizeof(data->dasd_io_times));
 367                 memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
 368                        sizeof(data->dasd_io_timps));
 369                 memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
 370                        sizeof(data->dasd_io_time1));
 371                 memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
 372                        sizeof(data->dasd_io_time2));
 373                 memcpy(data->dasd_io_time2ps,
 374                        block->profile.data->dasd_io_time2ps,
 375                        sizeof(data->dasd_io_time2ps));
 376                 memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
 377                        sizeof(data->dasd_io_time3));
 378                 memcpy(data->dasd_io_nr_req,
 379                        block->profile.data->dasd_io_nr_req,
 380                        sizeof(data->dasd_io_nr_req));
 381                 spin_unlock_bh(&block->profile.lock);
 382         } else {
 383                 spin_unlock_bh(&block->profile.lock);
 384                 rc = -EIO;
 385                 goto out;
 386         }
 387         if (copy_to_user(argp, data, sizeof(*data)))
 388                 rc = -EFAULT;
 389 out:
 390         kfree(data);
 391         return rc;
 392 }
 393 #else
 394 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 395 {
 396         return -ENOTTY;
 397 }
 398
 399 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 400 {
 401         return -ENOTTY;
 402 }
 403 #endif
 404
 405 /*
 406  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
 407  */
 408 static int dasd_ioctl_information(struct dasd_block *block,
 409                                   unsigned int cmd, void __user *argp)
 410 {
 411         struct dasd_information2_t *dasd_info;
 412         struct subchannel_id sch_id;
 413         struct ccw_dev_id dev_id;
 414         struct dasd_device *base;
 415         struct ccw_device *cdev;
 416         unsigned long flags;
 417         int rc;
 418
 419         base = block->base;
 420         if (!base->discipline || !base->discipline->fill_info)
 421                 return -EINVAL;
 422
 423         dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
 424         if (dasd_info == NULL)
 425                 return -ENOMEM;
 426
 427         rc = base->discipline->fill_info(base, dasd_info);
 428         if (rc) {
 429                 kfree(dasd_info);
 430                 return rc;
 431         }
 432
 433         cdev = base->cdev;
 434         ccw_device_get_id(cdev, &dev_id);
 435         ccw_device_get_schid(cdev, &sch_id);
 436
 437         dasd_info->devno = dev_id.devno;
 438         dasd_info->schid = sch_id.sch_no;
 439         dasd_info->cu_type = cdev->id.cu_type;
 440         dasd_info->cu_model = cdev->id.cu_model;
 441         dasd_info->dev_type = cdev->id.dev_type;
 442         dasd_info->dev_model = cdev->id.dev_model;
 443         dasd_info->status = base->state;
 444         /*
 445          * The open_count is increased for every opener, that includes
 446          * the blkdev_get in dasd_scan_partitions.
 447          * This must be hidden from user-space.
 448          */
 449         dasd_info->open_count = atomic_read(&block->open_count);
 450         if (!block->bdev)
 451                 dasd_info->open_count++;
 452
 453         /*
 454          * check if device is really formatted
 455          * LDL / CDL was returned by 'fill_info'
 456          */
 457         if ((base->state < DASD_STATE_READY) ||
 458             (dasd_check_blocksize(block->bp_block)))
 459                 dasd_info->format = DASD_FORMAT_NONE;
 460
 461         dasd_info->features |=
 462                 ((base->features & DASD_FEATURE_READONLY) != 0);
 463
 464         memcpy(dasd_info->type, base->discipline->name, 4);
 465
 466         if (block->request_queue->request_fn) {
 467                 struct list_head *l;
 468 #ifdef DASD_EXTENDED_PROFILING
 469                 {
 470                         struct list_head *l;
 471                         spin_lock_irqsave(&block->lock, flags);
 472                         list_for_each(l, &block->request_queue->queue_head)
 473                                 dasd_info->req_queue_len++;
 474                         spin_unlock_irqrestore(&block->lock, flags);
 475                 }
 476 #endif                          /* DASD_EXTENDED_PROFILING */
 477                 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 478                 list_for_each(l, &base->ccw_queue)
 479                         dasd_info->chanq_len++;
 480                 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
 481                                        flags);
 482         }
 483
 484         rc = 0;
 485         if (copy_to_user(argp, dasd_info,
 486                          ((cmd == (unsigned int) BIODASDINFO2) ?
 487                           sizeof(struct dasd_information2_t) :
 488                           sizeof(struct dasd_information_t))))
 489                 rc = -EFAULT;
 490         kfree(dasd_info);
 491         return rc;
 492 }
 493
 494 /*
 495  * Set read only
 496  */
 497 static int
 498 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
 499 {
 500         struct dasd_device *base;
 501         int intval, rc;
 502
 503         if (!capable(CAP_SYS_ADMIN))
 504                 return -EACCES;
 505         if (bdev != bdev->bd_contains)
 506                 // ro setting is not allowed for partitions
 507                 return -EINVAL;
 508         if (get_user(intval, (int __user *)argp))
 509                 return -EFAULT;
 510         base = dasd_device_from_gendisk(bdev->bd_disk);
 511         if (!base)
 512                 return -ENODEV;
 513         if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 514                 dasd_put_device(base);
 515                 return -EROFS;
 516         }
 517         set_disk_ro(bdev->bd_disk, intval);
 518         rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
 519         dasd_put_device(base);
 520         return rc;
 521 }
 522
 523 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
 524                                   struct cmbdata __user *argp)
 525 {
 526         size_t size = _IOC_SIZE(cmd);
 527         struct cmbdata data;
 528         int ret;
 529
 530         ret = cmf_readall(block->base->cdev, &data);
 531         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
 532                 return -EFAULT;
 533         return ret;
 534 }
 535
 536 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
 537                unsigned int cmd, unsigned long arg)
 538 {
 539         struct dasd_block *block;
 540         struct dasd_device *base;
 541         void __user *argp;
 542         int rc;
 543
 544         if (is_compat_task())
 545                 argp = compat_ptr(arg);
 546         else
 547                 argp = (void __user *)arg;
 548
 549         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
 550                 PRINT_DEBUG("empty data ptr");
 551                 return -EINVAL;
 552         }
 553
 554         base = dasd_device_from_gendisk(bdev->bd_disk);
 555         if (!base)
 556                 return -ENODEV;
 557         block = base->block;
 558         rc = 0;
 559         switch (cmd) {
 560         case BIODASDDISABLE:
 561                 rc = dasd_ioctl_disable(bdev);
 562                 break;
 563         case BIODASDENABLE:
 564                 rc = dasd_ioctl_enable(bdev);
 565                 break;
 566         case BIODASDQUIESCE:
 567                 rc = dasd_ioctl_quiesce(block);
 568                 break;
 569         case BIODASDRESUME:
 570                 rc = dasd_ioctl_resume(block);
 571                 break;
 572         case BIODASDABORTIO:
 573                 rc = dasd_ioctl_abortio(block);
 574                 break;
 575         case BIODASDALLOWIO:
 576                 rc = dasd_ioctl_allowio(block);
 577                 break;
 578         case BIODASDFMT:
 579                 rc = dasd_ioctl_format(bdev, argp);
 580                 break;
 581         case BIODASDCHECKFMT:
 582                 rc = dasd_ioctl_check_format(bdev, argp);
 583                 break;
 584         case BIODASDINFO:
 585                 rc = dasd_ioctl_information(block, cmd, argp);
 586                 break;
 587         case BIODASDINFO2:
 588                 rc = dasd_ioctl_information(block, cmd, argp);
 589                 break;
 590         case BIODASDPRRD:
 591                 rc = dasd_ioctl_read_profile(block, argp);
 592                 break;
 593         case BIODASDPRRST:
 594                 rc = dasd_ioctl_reset_profile(block);
 595                 break;
 596         case BLKROSET:
 597                 rc = dasd_ioctl_set_ro(bdev, argp);
 598                 break;
 599         case DASDAPIVER:
 600                 rc = dasd_ioctl_api_version(argp);
 601                 break;
 602         case BIODASDCMFENABLE:
 603                 rc = enable_cmf(base->cdev);
 604                 break;
 605         case BIODASDCMFDISABLE:
 606                 rc = disable_cmf(base->cdev);
 607                 break;
 608         case BIODASDREADALLCMB:
 609                 rc = dasd_ioctl_readall_cmb(block, cmd, argp);
 610                 break;
 611         default:
 612                 /* if the discipline has an ioctl method try it. */
 613                 rc = -ENOTTY;
 614                 if (base->discipline->ioctl)
 615                         rc = base->discipline->ioctl(block, cmd, argp);
 616         }
 617         dasd_put_device(base);
 618         return rc;
 619 }