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
  26 /* This is ugly... */
  27 #define PRINTK_HEADER "dasd_ioctl:"
  28
  29 #include "dasd_int.h"
  30
  31
  32 static int
  33 dasd_ioctl_api_version(void __user *argp)
  34 {
  35         int ver = DASD_API_VERSION;
  36         return put_user(ver, (int __user *)argp);
  37 }
  38
  39 /*
  40  * Enable device.
  41  * used by dasdfmt after BIODASDDISABLE to retrigger blocksize detection
  42  */
  43 static int
  44 dasd_ioctl_enable(struct block_device *bdev)
  45 {
  46         struct dasd_device *base;
  47
  48         if (!capable(CAP_SYS_ADMIN))
  49                 return -EACCES;
  50
  51         base = dasd_device_from_gendisk(bdev->bd_disk);
  52         if (!base)
  53                 return -ENODEV;
  54
  55         dasd_enable_device(base);
  56         /* Formatting the dasd device can change the capacity. */
  57         mutex_lock(&bdev->bd_mutex);
  58         i_size_write(bdev->bd_inode,
  59                      (loff_t)get_capacity(base->block->gdp) << 9);
  60         mutex_unlock(&bdev->bd_mutex);
  61         dasd_put_device(base);
  62         return 0;
  63 }
  64
  65 /*
  66  * Disable device.
  67  * Used by dasdfmt. Disable I/O operations but allow ioctls.
  68  */
  69 static int
  70 dasd_ioctl_disable(struct block_device *bdev)
  71 {
  72         struct dasd_device *base;
  73
  74         if (!capable(CAP_SYS_ADMIN))
  75                 return -EACCES;
  76
  77         base = dasd_device_from_gendisk(bdev->bd_disk);
  78         if (!base)
  79                 return -ENODEV;
  80         /*
  81          * Man this is sick. We don't do a real disable but only downgrade
  82          * the device to DASD_STATE_BASIC. The reason is that dasdfmt uses
  83          * BIODASDDISABLE to disable accesses to the device via the block
  84          * device layer but it still wants to do i/o on the device by
  85          * using the BIODASDFMT ioctl. Therefore the correct state for the
  86          * device is DASD_STATE_BASIC that allows to do basic i/o.
  87          */
  88         dasd_set_target_state(base, DASD_STATE_BASIC);
  89         /*
  90          * Set i_size to zero, since read, write, etc. check against this
  91          * value.
  92          */
  93         mutex_lock(&bdev->bd_mutex);
  94         i_size_write(bdev->bd_inode, 0);
  95         mutex_unlock(&bdev->bd_mutex);
  96         dasd_put_device(base);
  97         return 0;
  98 }
  99
 100 /*
 101  * Quiesce device.
 102  */
 103 static int dasd_ioctl_quiesce(struct dasd_block *block)
 104 {
 105         unsigned long flags;
 106         struct dasd_device *base;
 107
 108         base = block->base;
 109         if (!capable (CAP_SYS_ADMIN))
 110                 return -EACCES;
 111
 112         pr_info("%s: The DASD has been put in the quiesce "
 113                 "state\n", dev_name(&base->cdev->dev));
 114         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 115         dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
 116         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 117         return 0;
 118 }
 119
 120
 121 /*
 122  * Resume device.
 123  */
 124 static int dasd_ioctl_resume(struct dasd_block *block)
 125 {
 126         unsigned long flags;
 127         struct dasd_device *base;
 128
 129         base = block->base;
 130         if (!capable (CAP_SYS_ADMIN))
 131                 return -EACCES;
 132
 133         pr_info("%s: I/O operations have been resumed "
 134                 "on the DASD\n", dev_name(&base->cdev->dev));
 135         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 136         dasd_device_remove_stop_bits(base, DASD_STOPPED_QUIESCE);
 137         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), flags);
 138
 139         dasd_schedule_block_bh(block);
 140         return 0;
 141 }
 142
 143 /*
 144  * Abort all failfast I/O on a device.
 145  */
 146 static int dasd_ioctl_abortio(struct dasd_block *block)
 147 {
 148         unsigned long flags;
 149         struct dasd_device *base;
 150         struct dasd_ccw_req *cqr, *n;
 151
 152         base = block->base;
 153         if (!capable(CAP_SYS_ADMIN))
 154                 return -EACCES;
 155
 156         if (test_and_set_bit(DASD_FLAG_ABORTALL, &base->flags))
 157                 return 0;
 158         DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag set");
 159
 160         spin_lock_irqsave(&block->request_queue_lock, flags);
 161         spin_lock(&block->queue_lock);
 162         list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
 163                 if (test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
 164                     cqr->callback_data &&
 165                     cqr->callback_data != DASD_SLEEPON_START_TAG &&
 166                     cqr->callback_data != DASD_SLEEPON_END_TAG) {
 167                         spin_unlock(&block->queue_lock);
 168                         blk_abort_request(cqr->callback_data);
 169                         spin_lock(&block->queue_lock);
 170                 }
 171         }
 172         spin_unlock(&block->queue_lock);
 173         spin_unlock_irqrestore(&block->request_queue_lock, flags);
 174
 175         dasd_schedule_block_bh(block);
 176         return 0;
 177 }
 178
 179 /*
 180  * Allow I/O on a device
 181  */
 182 static int dasd_ioctl_allowio(struct dasd_block *block)
 183 {
 184         struct dasd_device *base;
 185
 186         base = block->base;
 187         if (!capable(CAP_SYS_ADMIN))
 188                 return -EACCES;
 189
 190         if (test_and_clear_bit(DASD_FLAG_ABORTALL, &base->flags))
 191                 DBF_DEV_EVENT(DBF_NOTICE, base, "%s", "abortall flag unset");
 192
 193         return 0;
 194 }
 195
 196 /*
 197  * performs formatting of _device_ according to _fdata_
 198  * Note: The discipline's format_function is assumed to deliver formatting
 199  * commands to format multiple units of the device. In terms of the ECKD
 200  * devices this means CCWs are generated to format multiple tracks.
 201  */
 202 static int
 203 dasd_format(struct dasd_block *block, struct format_data_t *fdata)
 204 {
 205         struct dasd_device *base;
 206         int rc;
 207
 208         base = block->base;
 209         if (base->discipline->format_device == NULL)
 210                 return -EPERM;
 211
 212         if (base->state != DASD_STATE_BASIC) {
 213                 pr_warn("%s: The DASD cannot be formatted while it is enabled\n",
 214                         dev_name(&base->cdev->dev));
 215                 return -EBUSY;
 216         }
 217
 218         DBF_DEV_EVENT(DBF_NOTICE, base,
 219                       "formatting units %u to %u (%u B blocks) flags %u",
 220                       fdata->start_unit,
 221                       fdata->stop_unit, fdata->blksize, fdata->intensity);
 222
 223         /* Since dasdfmt keeps the device open after it was disabled,
 224          * there still exists an inode for this device.
 225          * We must update i_blkbits, otherwise we might get errors when
 226          * enabling the device later.
 227          */
 228         if (fdata->start_unit == 0) {
 229                 struct block_device *bdev = bdget_disk(block->gdp, 0);
 230                 bdev->bd_inode->i_blkbits = blksize_bits(fdata->blksize);
 231                 bdput(bdev);
 232         }
 233
 234         rc = base->discipline->format_device(base, fdata, 1);
 235         if (rc == -EAGAIN)
 236                 rc = base->discipline->format_device(base, fdata, 0);
 237
 238         return rc;
 239 }
 240
 241 static int dasd_check_format(struct dasd_block *block,
 242                              struct format_check_t *cdata)
 243 {
 244         struct dasd_device *base;
 245         int rc;
 246
 247         base = block->base;
 248         if (!base->discipline->check_device_format)
 249                 return -ENOTTY;
 250
 251         rc = base->discipline->check_device_format(base, cdata, 1);
 252         if (rc == -EAGAIN)
 253                 rc = base->discipline->check_device_format(base, cdata, 0);
 254
 255         return rc;
 256 }
 257
 258 /*
 259  * Format device.
 260  */
 261 static int
 262 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
 263 {
 264         struct dasd_device *base;
 265         struct format_data_t fdata;
 266         int rc;
 267
 268         if (!capable(CAP_SYS_ADMIN))
 269                 return -EACCES;
 270         if (!argp)
 271                 return -EINVAL;
 272         base = dasd_device_from_gendisk(bdev->bd_disk);
 273         if (!base)
 274                 return -ENODEV;
 275         if (base->features & DASD_FEATURE_READONLY ||
 276             test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 277                 dasd_put_device(base);
 278                 return -EROFS;
 279         }
 280         if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
 281                 dasd_put_device(base);
 282                 return -EFAULT;
 283         }
 284         if (bdev != bdev->bd_contains) {
 285                 pr_warn("%s: The specified DASD is a partition and cannot be formatted\n",
 286                         dev_name(&base->cdev->dev));
 287                 dasd_put_device(base);
 288                 return -EINVAL;
 289         }
 290         rc = dasd_format(base->block, &fdata);
 291         dasd_put_device(base);
 292
 293         return rc;
 294 }
 295
 296 /*
 297  * Check device format
 298  */
 299 static int dasd_ioctl_check_format(struct block_device *bdev, void __user *argp)
 300 {
 301         struct format_check_t cdata;
 302         struct dasd_device *base;
 303         int rc = 0;
 304
 305         if (!argp)
 306                 return -EINVAL;
 307
 308         base = dasd_device_from_gendisk(bdev->bd_disk);
 309         if (!base)
 310                 return -ENODEV;
 311         if (bdev != bdev->bd_contains) {
 312                 pr_warn("%s: The specified DASD is a partition and cannot be checked\n",
 313                         dev_name(&base->cdev->dev));
 314                 rc = -EINVAL;
 315                 goto out_err;
 316         }
 317
 318         if (copy_from_user(&cdata, argp, sizeof(cdata))) {
 319                 rc = -EFAULT;
 320                 goto out_err;
 321         }
 322
 323         rc = dasd_check_format(base->block, &cdata);
 324         if (rc)
 325                 goto out_err;
 326
 327         if (copy_to_user(argp, &cdata, sizeof(cdata)))
 328                 rc = -EFAULT;
 329
 330 out_err:
 331         dasd_put_device(base);
 332
 333         return rc;
 334 }
 335
 336 #ifdef CONFIG_DASD_PROFILE
 337 /*
 338  * Reset device profile information
 339  */
 340 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 341 {
 342         dasd_profile_reset(&block->profile);
 343         return 0;
 344 }
 345
 346 /*
 347  * Return device profile information
 348  */
 349 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 350 {
 351         struct dasd_profile_info_t *data;
 352         int rc = 0;
 353
 354         data = kmalloc(sizeof(*data), GFP_KERNEL);
 355         if (!data)
 356                 return -ENOMEM;
 357
 358         spin_lock_bh(&block->profile.lock);
 359         if (block->profile.data) {
 360                 data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
 361                 data->dasd_io_sects = block->profile.data->dasd_io_sects;
 362                 memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
 363                        sizeof(data->dasd_io_secs));
 364                 memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
 365                        sizeof(data->dasd_io_times));
 366                 memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
 367                        sizeof(data->dasd_io_timps));
 368                 memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
 369                        sizeof(data->dasd_io_time1));
 370                 memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
 371                        sizeof(data->dasd_io_time2));
 372                 memcpy(data->dasd_io_time2ps,
 373                        block->profile.data->dasd_io_time2ps,
 374                        sizeof(data->dasd_io_time2ps));
 375                 memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
 376                        sizeof(data->dasd_io_time3));
 377                 memcpy(data->dasd_io_nr_req,
 378                        block->profile.data->dasd_io_nr_req,
 379                        sizeof(data->dasd_io_nr_req));
 380                 spin_unlock_bh(&block->profile.lock);
 381         } else {
 382                 spin_unlock_bh(&block->profile.lock);
 383                 rc = -EIO;
 384                 goto out;
 385         }
 386         if (copy_to_user(argp, data, sizeof(*data)))
 387                 rc = -EFAULT;
 388 out:
 389         kfree(data);
 390         return rc;
 391 }
 392 #else
 393 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 394 {
 395         return -ENOTTY;
 396 }
 397
 398 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 399 {
 400         return -ENOTTY;
 401 }
 402 #endif
 403
 404 /*
 405  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
 406  */
 407 static int dasd_ioctl_information(struct dasd_block *block,
 408                                   unsigned int cmd, void __user *argp)
 409 {
 410         struct dasd_information2_t *dasd_info;
 411         struct subchannel_id sch_id;
 412         struct ccw_dev_id dev_id;
 413         struct dasd_device *base;
 414         struct ccw_device *cdev;
 415         struct list_head *l;
 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         spin_lock_irqsave(&block->queue_lock, flags);
 467         list_for_each(l, &base->ccw_queue)
 468                 dasd_info->chanq_len++;
 469         spin_unlock_irqrestore(&block->queue_lock, flags);
 470
 471         rc = 0;
 472         if (copy_to_user(argp, dasd_info,
 473                          ((cmd == (unsigned int) BIODASDINFO2) ?
 474                           sizeof(struct dasd_information2_t) :
 475                           sizeof(struct dasd_information_t))))
 476                 rc = -EFAULT;
 477         kfree(dasd_info);
 478         return rc;
 479 }
 480
 481 /*
 482  * Set read only
 483  */
 484 static int
 485 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
 486 {
 487         struct dasd_device *base;
 488         int intval, rc;
 489
 490         if (!capable(CAP_SYS_ADMIN))
 491                 return -EACCES;
 492         if (bdev != bdev->bd_contains)
 493                 // ro setting is not allowed for partitions
 494                 return -EINVAL;
 495         if (get_user(intval, (int __user *)argp))
 496                 return -EFAULT;
 497         base = dasd_device_from_gendisk(bdev->bd_disk);
 498         if (!base)
 499                 return -ENODEV;
 500         if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 501                 dasd_put_device(base);
 502                 return -EROFS;
 503         }
 504         set_disk_ro(bdev->bd_disk, intval);
 505         rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
 506         dasd_put_device(base);
 507         return rc;
 508 }
 509
 510 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
 511                                   struct cmbdata __user *argp)
 512 {
 513         size_t size = _IOC_SIZE(cmd);
 514         struct cmbdata data;
 515         int ret;
 516
 517         ret = cmf_readall(block->base->cdev, &data);
 518         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
 519                 return -EFAULT;
 520         return ret;
 521 }
 522
 523 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
 524                unsigned int cmd, unsigned long arg)
 525 {
 526         struct dasd_block *block;
 527         struct dasd_device *base;
 528         void __user *argp;
 529         int rc;
 530
 531         if (is_compat_task())
 532                 argp = compat_ptr(arg);
 533         else
 534                 argp = (void __user *)arg;
 535
 536         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
 537                 PRINT_DEBUG("empty data ptr");
 538                 return -EINVAL;
 539         }
 540
 541         base = dasd_device_from_gendisk(bdev->bd_disk);
 542         if (!base)
 543                 return -ENODEV;
 544         block = base->block;
 545         rc = 0;
 546         switch (cmd) {
 547         case BIODASDDISABLE:
 548                 rc = dasd_ioctl_disable(bdev);
 549                 break;
 550         case BIODASDENABLE:
 551                 rc = dasd_ioctl_enable(bdev);
 552                 break;
 553         case BIODASDQUIESCE:
 554                 rc = dasd_ioctl_quiesce(block);
 555                 break;
 556         case BIODASDRESUME:
 557                 rc = dasd_ioctl_resume(block);
 558                 break;
 559         case BIODASDABORTIO:
 560                 rc = dasd_ioctl_abortio(block);
 561                 break;
 562         case BIODASDALLOWIO:
 563                 rc = dasd_ioctl_allowio(block);
 564                 break;
 565         case BIODASDFMT:
 566                 rc = dasd_ioctl_format(bdev, argp);
 567                 break;
 568         case BIODASDCHECKFMT:
 569                 rc = dasd_ioctl_check_format(bdev, argp);
 570                 break;
 571         case BIODASDINFO:
 572                 rc = dasd_ioctl_information(block, cmd, argp);
 573                 break;
 574         case BIODASDINFO2:
 575                 rc = dasd_ioctl_information(block, cmd, argp);
 576                 break;
 577         case BIODASDPRRD:
 578                 rc = dasd_ioctl_read_profile(block, argp);
 579                 break;
 580         case BIODASDPRRST:
 581                 rc = dasd_ioctl_reset_profile(block);
 582                 break;
 583         case BLKROSET:
 584                 rc = dasd_ioctl_set_ro(bdev, argp);
 585                 break;
 586         case DASDAPIVER:
 587                 rc = dasd_ioctl_api_version(argp);
 588                 break;
 589         case BIODASDCMFENABLE:
 590                 rc = enable_cmf(base->cdev);
 591                 break;
 592         case BIODASDCMFDISABLE:
 593                 rc = disable_cmf(base->cdev);
 594                 break;
 595         case BIODASDREADALLCMB:
 596                 rc = dasd_ioctl_readall_cmb(block, cmd, argp);
 597                 break;
 598         default:
 599                 /* if the discipline has an ioctl method try it. */
 600                 rc = -ENOTTY;
 601                 if (base->discipline->ioctl)
 602                         rc = base->discipline->ioctl(block, cmd, argp);
 603         }
 604         dasd_put_device(base);
 605         return rc;
 606 }