drivers/s390/block/dasd_ioctl.c

   1 /*
   2  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   3  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
   4  *                  Carsten Otte <Cotte@de.ibm.com>
   5  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
   6  * Bugreports.to..: <Linux390@de.ibm.com>
   7  * Copyright IBM Corp. 1999, 2001
   8  *
   9  * i/o controls for the dasd driver.
  10  */
  11
  12 #define KMSG_COMPONENT "dasd"
  13
  14 #include <linux/interrupt.h>
  15 #include <linux/compat.h>
  16 #include <linux/major.h>
  17 #include <linux/fs.h>
  18 #include <linux/blkpg.h>
  19 #include <linux/slab.h>
  20 #include <asm/compat.h>
  21 #include <asm/ccwdev.h>
  22 #include <asm/schid.h>
  23 #include <asm/cmb.h>
  24 #include <asm/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 /*
 242  * Format device.
 243  */
 244 static int
 245 dasd_ioctl_format(struct block_device *bdev, void __user *argp)
 246 {
 247         struct dasd_device *base;
 248         struct format_data_t fdata;
 249         int rc;
 250
 251         if (!capable(CAP_SYS_ADMIN))
 252                 return -EACCES;
 253         if (!argp)
 254                 return -EINVAL;
 255         base = dasd_device_from_gendisk(bdev->bd_disk);
 256         if (!base)
 257                 return -ENODEV;
 258         if (base->features & DASD_FEATURE_READONLY ||
 259             test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 260                 dasd_put_device(base);
 261                 return -EROFS;
 262         }
 263         if (copy_from_user(&fdata, argp, sizeof(struct format_data_t))) {
 264                 dasd_put_device(base);
 265                 return -EFAULT;
 266         }
 267         if (bdev != bdev->bd_contains) {
 268                 pr_warn("%s: The specified DASD is a partition and cannot be formatted\n",
 269                         dev_name(&base->cdev->dev));
 270                 dasd_put_device(base);
 271                 return -EINVAL;
 272         }
 273         rc = dasd_format(base->block, &fdata);
 274         dasd_put_device(base);
 275         return rc;
 276 }
 277
 278 #ifdef CONFIG_DASD_PROFILE
 279 /*
 280  * Reset device profile information
 281  */
 282 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 283 {
 284         dasd_profile_reset(&block->profile);
 285         return 0;
 286 }
 287
 288 /*
 289  * Return device profile information
 290  */
 291 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 292 {
 293         struct dasd_profile_info_t *data;
 294         int rc = 0;
 295
 296         data = kmalloc(sizeof(*data), GFP_KERNEL);
 297         if (!data)
 298                 return -ENOMEM;
 299
 300         spin_lock_bh(&block->profile.lock);
 301         if (block->profile.data) {
 302                 data->dasd_io_reqs = block->profile.data->dasd_io_reqs;
 303                 data->dasd_io_sects = block->profile.data->dasd_io_sects;
 304                 memcpy(data->dasd_io_secs, block->profile.data->dasd_io_secs,
 305                        sizeof(data->dasd_io_secs));
 306                 memcpy(data->dasd_io_times, block->profile.data->dasd_io_times,
 307                        sizeof(data->dasd_io_times));
 308                 memcpy(data->dasd_io_timps, block->profile.data->dasd_io_timps,
 309                        sizeof(data->dasd_io_timps));
 310                 memcpy(data->dasd_io_time1, block->profile.data->dasd_io_time1,
 311                        sizeof(data->dasd_io_time1));
 312                 memcpy(data->dasd_io_time2, block->profile.data->dasd_io_time2,
 313                        sizeof(data->dasd_io_time2));
 314                 memcpy(data->dasd_io_time2ps,
 315                        block->profile.data->dasd_io_time2ps,
 316                        sizeof(data->dasd_io_time2ps));
 317                 memcpy(data->dasd_io_time3, block->profile.data->dasd_io_time3,
 318                        sizeof(data->dasd_io_time3));
 319                 memcpy(data->dasd_io_nr_req,
 320                        block->profile.data->dasd_io_nr_req,
 321                        sizeof(data->dasd_io_nr_req));
 322                 spin_unlock_bh(&block->profile.lock);
 323         } else {
 324                 spin_unlock_bh(&block->profile.lock);
 325                 rc = -EIO;
 326                 goto out;
 327         }
 328         if (copy_to_user(argp, data, sizeof(*data)))
 329                 rc = -EFAULT;
 330 out:
 331         kfree(data);
 332         return rc;
 333 }
 334 #else
 335 static int dasd_ioctl_reset_profile(struct dasd_block *block)
 336 {
 337         return -ENOTTY;
 338 }
 339
 340 static int dasd_ioctl_read_profile(struct dasd_block *block, void __user *argp)
 341 {
 342         return -ENOTTY;
 343 }
 344 #endif
 345
 346 /*
 347  * Return dasd information. Used for BIODASDINFO and BIODASDINFO2.
 348  */
 349 static int dasd_ioctl_information(struct dasd_block *block,
 350                                   unsigned int cmd, void __user *argp)
 351 {
 352         struct dasd_information2_t *dasd_info;
 353         struct subchannel_id sch_id;
 354         struct ccw_dev_id dev_id;
 355         struct dasd_device *base;
 356         struct ccw_device *cdev;
 357         unsigned long flags;
 358         int rc;
 359
 360         base = block->base;
 361         if (!base->discipline || !base->discipline->fill_info)
 362                 return -EINVAL;
 363
 364         dasd_info = kzalloc(sizeof(struct dasd_information2_t), GFP_KERNEL);
 365         if (dasd_info == NULL)
 366                 return -ENOMEM;
 367
 368         rc = base->discipline->fill_info(base, dasd_info);
 369         if (rc) {
 370                 kfree(dasd_info);
 371                 return rc;
 372         }
 373
 374         cdev = base->cdev;
 375         ccw_device_get_id(cdev, &dev_id);
 376         ccw_device_get_schid(cdev, &sch_id);
 377
 378         dasd_info->devno = dev_id.devno;
 379         dasd_info->schid = sch_id.sch_no;
 380         dasd_info->cu_type = cdev->id.cu_type;
 381         dasd_info->cu_model = cdev->id.cu_model;
 382         dasd_info->dev_type = cdev->id.dev_type;
 383         dasd_info->dev_model = cdev->id.dev_model;
 384         dasd_info->status = base->state;
 385         /*
 386          * The open_count is increased for every opener, that includes
 387          * the blkdev_get in dasd_scan_partitions.
 388          * This must be hidden from user-space.
 389          */
 390         dasd_info->open_count = atomic_read(&block->open_count);
 391         if (!block->bdev)
 392                 dasd_info->open_count++;
 393
 394         /*
 395          * check if device is really formatted
 396          * LDL / CDL was returned by 'fill_info'
 397          */
 398         if ((base->state < DASD_STATE_READY) ||
 399             (dasd_check_blocksize(block->bp_block)))
 400                 dasd_info->format = DASD_FORMAT_NONE;
 401
 402         dasd_info->features |=
 403                 ((base->features & DASD_FEATURE_READONLY) != 0);
 404
 405         memcpy(dasd_info->type, base->discipline->name, 4);
 406
 407         if (block->request_queue->request_fn) {
 408                 struct list_head *l;
 409 #ifdef DASD_EXTENDED_PROFILING
 410                 {
 411                         struct list_head *l;
 412                         spin_lock_irqsave(&block->lock, flags);
 413                         list_for_each(l, &block->request_queue->queue_head)
 414                                 dasd_info->req_queue_len++;
 415                         spin_unlock_irqrestore(&block->lock, flags);
 416                 }
 417 #endif                          /* DASD_EXTENDED_PROFILING */
 418                 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
 419                 list_for_each(l, &base->ccw_queue)
 420                         dasd_info->chanq_len++;
 421                 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
 422                                        flags);
 423         }
 424
 425         rc = 0;
 426         if (copy_to_user(argp, dasd_info,
 427                          ((cmd == (unsigned int) BIODASDINFO2) ?
 428                           sizeof(struct dasd_information2_t) :
 429                           sizeof(struct dasd_information_t))))
 430                 rc = -EFAULT;
 431         kfree(dasd_info);
 432         return rc;
 433 }
 434
 435 /*
 436  * Set read only
 437  */
 438 static int
 439 dasd_ioctl_set_ro(struct block_device *bdev, void __user *argp)
 440 {
 441         struct dasd_device *base;
 442         int intval, rc;
 443
 444         if (!capable(CAP_SYS_ADMIN))
 445                 return -EACCES;
 446         if (bdev != bdev->bd_contains)
 447                 // ro setting is not allowed for partitions
 448                 return -EINVAL;
 449         if (get_user(intval, (int __user *)argp))
 450                 return -EFAULT;
 451         base = dasd_device_from_gendisk(bdev->bd_disk);
 452         if (!base)
 453                 return -ENODEV;
 454         if (!intval && test_bit(DASD_FLAG_DEVICE_RO, &base->flags)) {
 455                 dasd_put_device(base);
 456                 return -EROFS;
 457         }
 458         set_disk_ro(bdev->bd_disk, intval);
 459         rc = dasd_set_feature(base->cdev, DASD_FEATURE_READONLY, intval);
 460         dasd_put_device(base);
 461         return rc;
 462 }
 463
 464 static int dasd_ioctl_readall_cmb(struct dasd_block *block, unsigned int cmd,
 465                                   struct cmbdata __user *argp)
 466 {
 467         size_t size = _IOC_SIZE(cmd);
 468         struct cmbdata data;
 469         int ret;
 470
 471         ret = cmf_readall(block->base->cdev, &data);
 472         if (!ret && copy_to_user(argp, &data, min(size, sizeof(*argp))))
 473                 return -EFAULT;
 474         return ret;
 475 }
 476
 477 int dasd_ioctl(struct block_device *bdev, fmode_t mode,
 478                unsigned int cmd, unsigned long arg)
 479 {
 480         struct dasd_block *block;
 481         struct dasd_device *base;
 482         void __user *argp;
 483         int rc;
 484
 485         if (is_compat_task())
 486                 argp = compat_ptr(arg);
 487         else
 488                 argp = (void __user *)arg;
 489
 490         if ((_IOC_DIR(cmd) != _IOC_NONE) && !arg) {
 491                 PRINT_DEBUG("empty data ptr");
 492                 return -EINVAL;
 493         }
 494
 495         base = dasd_device_from_gendisk(bdev->bd_disk);
 496         if (!base)
 497                 return -ENODEV;
 498         block = base->block;
 499         rc = 0;
 500         switch (cmd) {
 501         case BIODASDDISABLE:
 502                 rc = dasd_ioctl_disable(bdev);
 503                 break;
 504         case BIODASDENABLE:
 505                 rc = dasd_ioctl_enable(bdev);
 506                 break;
 507         case BIODASDQUIESCE:
 508                 rc = dasd_ioctl_quiesce(block);
 509                 break;
 510         case BIODASDRESUME:
 511                 rc = dasd_ioctl_resume(block);
 512                 break;
 513         case BIODASDABORTIO:
 514                 rc = dasd_ioctl_abortio(block);
 515                 break;
 516         case BIODASDALLOWIO:
 517                 rc = dasd_ioctl_allowio(block);
 518                 break;
 519         case BIODASDFMT:
 520                 rc = dasd_ioctl_format(bdev, argp);
 521                 break;
 522         case BIODASDINFO:
 523                 rc = dasd_ioctl_information(block, cmd, argp);
 524                 break;
 525         case BIODASDINFO2:
 526                 rc = dasd_ioctl_information(block, cmd, argp);
 527                 break;
 528         case BIODASDPRRD:
 529                 rc = dasd_ioctl_read_profile(block, argp);
 530                 break;
 531         case BIODASDPRRST:
 532                 rc = dasd_ioctl_reset_profile(block);
 533                 break;
 534         case BLKROSET:
 535                 rc = dasd_ioctl_set_ro(bdev, argp);
 536                 break;
 537         case DASDAPIVER:
 538                 rc = dasd_ioctl_api_version(argp);
 539                 break;
 540         case BIODASDCMFENABLE:
 541                 rc = enable_cmf(base->cdev);
 542                 break;
 543         case BIODASDCMFDISABLE:
 544                 rc = disable_cmf(base->cdev);
 545                 break;
 546         case BIODASDREADALLCMB:
 547                 rc = dasd_ioctl_readall_cmb(block, cmd, argp);
 548                 break;
 549         default:
 550                 /* if the discipline has an ioctl method try it. */
 551                 rc = -ENOTTY;
 552                 if (base->discipline->ioctl)
 553                         rc = base->discipline->ioctl(block, cmd, argp);
 554         }
 555         dasd_put_device(base);
 556         return rc;
 557 }