drivers/s390/char/tape_core.c

   1 /*
   2  *  drivers/s390/char/tape_core.c
   3  *    basic function of the tape device driver
   4  *
   5  *  S390 and zSeries version
   6  *    Copyright IBM Corp. 2001, 2009
   7  *    Author(s): Carsten Otte <cotte@de.ibm.com>
   8  *               Michael Holzheu <holzheu@de.ibm.com>
   9  *               Tuan Ngo-Anh <ngoanh@de.ibm.com>
  10  *               Martin Schwidefsky <schwidefsky@de.ibm.com>
  11  *               Stefan Bader <shbader@de.ibm.com>
  12  */
  13
  14 #define KMSG_COMPONENT "tape"
  15 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  16
  17 #include <linux/module.h>
  18 #include <linux/init.h>      // for kernel parameters
  19 #include <linux/kmod.h>      // for requesting modules
  20 #include <linux/spinlock.h>  // for locks
  21 #include <linux/vmalloc.h>
  22 #include <linux/list.h>
  23 #include <linux/slab.h>
  24
  25 #include <asm/types.h>       // for variable types
  26
  27 #define TAPE_DBF_AREA   tape_core_dbf
  28
  29 #include "tape.h"
  30 #include "tape_std.h"
  31
  32 #define LONG_BUSY_TIMEOUT 180 /* seconds */
  33
  34 static void __tape_do_irq (struct ccw_device *, unsigned long, struct irb *);
  35 static void tape_delayed_next_request(struct work_struct *);
  36 static void tape_long_busy_timeout(unsigned long data);
  37
  38 /*
  39  * One list to contain all tape devices of all disciplines, so
  40  * we can assign the devices to minor numbers of the same major
  41  * The list is protected by the rwlock
  42  */
  43 static LIST_HEAD(tape_device_list);
  44 static DEFINE_RWLOCK(tape_device_lock);
  45
  46 /*
  47  * Pointer to debug area.
  48  */
  49 debug_info_t *TAPE_DBF_AREA = NULL;
  50 EXPORT_SYMBOL(TAPE_DBF_AREA);
  51
  52 /*
  53  * Printable strings for tape enumerations.
  54  */
  55 const char *tape_state_verbose[TS_SIZE] =
  56 {
  57         [TS_UNUSED]   = "UNUSED",
  58         [TS_IN_USE]   = "IN_USE",
  59         [TS_BLKUSE]   = "BLKUSE",
  60         [TS_INIT]     = "INIT  ",
  61         [TS_NOT_OPER] = "NOT_OP"
  62 };
  63
  64 const char *tape_op_verbose[TO_SIZE] =
  65 {
  66         [TO_BLOCK] = "BLK",     [TO_BSB] = "BSB",
  67         [TO_BSF] = "BSF",       [TO_DSE] = "DSE",
  68         [TO_FSB] = "FSB",       [TO_FSF] = "FSF",
  69         [TO_LBL] = "LBL",       [TO_NOP] = "NOP",
  70         [TO_RBA] = "RBA",       [TO_RBI] = "RBI",
  71         [TO_RFO] = "RFO",       [TO_REW] = "REW",
  72         [TO_RUN] = "RUN",       [TO_WRI] = "WRI",
  73         [TO_WTM] = "WTM",       [TO_MSEN] = "MSN",
  74         [TO_LOAD] = "LOA",      [TO_READ_CONFIG] = "RCF",
  75         [TO_READ_ATTMSG] = "RAT",
  76         [TO_DIS] = "DIS",       [TO_ASSIGN] = "ASS",
  77         [TO_UNASSIGN] = "UAS",  [TO_CRYPT_ON] = "CON",
  78         [TO_CRYPT_OFF] = "COF", [TO_KEKL_SET] = "KLS",
  79         [TO_KEKL_QUERY] = "KLQ",[TO_RDC] = "RDC",
  80 };
  81
  82 static int devid_to_int(struct ccw_dev_id *dev_id)
  83 {
  84         return dev_id->devno + (dev_id->ssid << 16);
  85 }
  86
  87 /*
  88  * Some channel attached tape specific attributes.
  89  *
  90  * FIXME: In the future the first_minor and blocksize attribute should be
  91  *        replaced by a link to the cdev tree.
  92  */
  93 static ssize_t
  94 tape_medium_state_show(struct device *dev, struct device_attribute *attr, char *buf)
  95 {
  96         struct tape_device *tdev;
  97
  98         tdev = dev_get_drvdata(dev);
  99         return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->medium_state);
 100 }
 101
 102 static
 103 DEVICE_ATTR(medium_state, 0444, tape_medium_state_show, NULL);
 104
 105 static ssize_t
 106 tape_first_minor_show(struct device *dev, struct device_attribute *attr, char *buf)
 107 {
 108         struct tape_device *tdev;
 109
 110         tdev = dev_get_drvdata(dev);
 111         return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->first_minor);
 112 }
 113
 114 static
 115 DEVICE_ATTR(first_minor, 0444, tape_first_minor_show, NULL);
 116
 117 static ssize_t
 118 tape_state_show(struct device *dev, struct device_attribute *attr, char *buf)
 119 {
 120         struct tape_device *tdev;
 121
 122         tdev = dev_get_drvdata(dev);
 123         return scnprintf(buf, PAGE_SIZE, "%s\n", (tdev->first_minor < 0) ?
 124                 "OFFLINE" : tape_state_verbose[tdev->tape_state]);
 125 }
 126
 127 static
 128 DEVICE_ATTR(state, 0444, tape_state_show, NULL);
 129
 130 static ssize_t
 131 tape_operation_show(struct device *dev, struct device_attribute *attr, char *buf)
 132 {
 133         struct tape_device *tdev;
 134         ssize_t rc;
 135
 136         tdev = dev_get_drvdata(dev);
 137         if (tdev->first_minor < 0)
 138                 return scnprintf(buf, PAGE_SIZE, "N/A\n");
 139
 140         spin_lock_irq(get_ccwdev_lock(tdev->cdev));
 141         if (list_empty(&tdev->req_queue))
 142                 rc = scnprintf(buf, PAGE_SIZE, "---\n");
 143         else {
 144                 struct tape_request *req;
 145
 146                 req = list_entry(tdev->req_queue.next, struct tape_request,
 147                         list);
 148                 rc = scnprintf(buf,PAGE_SIZE, "%s\n", tape_op_verbose[req->op]);
 149         }
 150         spin_unlock_irq(get_ccwdev_lock(tdev->cdev));
 151         return rc;
 152 }
 153
 154 static
 155 DEVICE_ATTR(operation, 0444, tape_operation_show, NULL);
 156
 157 static ssize_t
 158 tape_blocksize_show(struct device *dev, struct device_attribute *attr, char *buf)
 159 {
 160         struct tape_device *tdev;
 161
 162         tdev = dev_get_drvdata(dev);
 163
 164         return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->char_data.block_size);
 165 }
 166
 167 static
 168 DEVICE_ATTR(blocksize, 0444, tape_blocksize_show, NULL);
 169
 170 static struct attribute *tape_attrs[] = {
 171         &dev_attr_medium_state.attr,
 172         &dev_attr_first_minor.attr,
 173         &dev_attr_state.attr,
 174         &dev_attr_operation.attr,
 175         &dev_attr_blocksize.attr,
 176         NULL
 177 };
 178
 179 static struct attribute_group tape_attr_group = {
 180         .attrs = tape_attrs,
 181 };
 182
 183 /*
 184  * Tape state functions
 185  */
 186 void
 187 tape_state_set(struct tape_device *device, enum tape_state newstate)
 188 {
 189         const char *str;
 190
 191         if (device->tape_state == TS_NOT_OPER) {
 192                 DBF_EVENT(3, "ts_set err: not oper\n");
 193                 return;
 194         }
 195         DBF_EVENT(4, "ts. dev:  %x\n", device->first_minor);
 196         DBF_EVENT(4, "old ts:\t\n");
 197         if (device->tape_state < TS_SIZE && device->tape_state >=0 )
 198                 str = tape_state_verbose[device->tape_state];
 199         else
 200                 str = "UNKNOWN TS";
 201         DBF_EVENT(4, "%s\n", str);
 202         DBF_EVENT(4, "new ts:\t\n");
 203         if (newstate < TS_SIZE && newstate >= 0)
 204                 str = tape_state_verbose[newstate];
 205         else
 206                 str = "UNKNOWN TS";
 207         DBF_EVENT(4, "%s\n", str);
 208         device->tape_state = newstate;
 209         wake_up(&device->state_change_wq);
 210 }
 211
 212 struct tape_med_state_work_data {
 213         struct tape_device *device;
 214         enum tape_medium_state state;
 215         struct work_struct  work;
 216 };
 217
 218 static void
 219 tape_med_state_work_handler(struct work_struct *work)
 220 {
 221         static char env_state_loaded[] = "MEDIUM_STATE=LOADED";
 222         static char env_state_unloaded[] = "MEDIUM_STATE=UNLOADED";
 223         struct tape_med_state_work_data *p =
 224                 container_of(work, struct tape_med_state_work_data, work);
 225         struct tape_device *device = p->device;
 226         char *envp[] = { NULL, NULL };
 227
 228         switch (p->state) {
 229         case MS_UNLOADED:
 230                 pr_info("%s: The tape cartridge has been successfully "
 231                         "unloaded\n", dev_name(&device->cdev->dev));
 232                 envp[0] = env_state_unloaded;
 233                 kobject_uevent_env(&device->cdev->dev.kobj, KOBJ_CHANGE, envp);
 234                 break;
 235         case MS_LOADED:
 236                 pr_info("%s: A tape cartridge has been mounted\n",
 237                         dev_name(&device->cdev->dev));
 238                 envp[0] = env_state_loaded;
 239                 kobject_uevent_env(&device->cdev->dev.kobj, KOBJ_CHANGE, envp);
 240                 break;
 241         default:
 242                 break;
 243         }
 244         tape_put_device(device);
 245         kfree(p);
 246 }
 247
 248 static void
 249 tape_med_state_work(struct tape_device *device, enum tape_medium_state state)
 250 {
 251         struct tape_med_state_work_data *p;
 252
 253         p = kzalloc(sizeof(*p), GFP_ATOMIC);
 254         if (p) {
 255                 INIT_WORK(&p->work, tape_med_state_work_handler);
 256                 p->device = tape_get_device(device);
 257                 p->state = state;
 258                 schedule_work(&p->work);
 259         }
 260 }
 261
 262 void
 263 tape_med_state_set(struct tape_device *device, enum tape_medium_state newstate)
 264 {
 265         enum tape_medium_state oldstate;
 266
 267         oldstate = device->medium_state;
 268         if (oldstate == newstate)
 269                 return;
 270         device->medium_state = newstate;
 271         switch(newstate){
 272         case MS_UNLOADED:
 273                 device->tape_generic_status |= GMT_DR_OPEN(~0);
 274                 if (oldstate == MS_LOADED)
 275                         tape_med_state_work(device, MS_UNLOADED);
 276                 break;
 277         case MS_LOADED:
 278                 device->tape_generic_status &= ~GMT_DR_OPEN(~0);
 279                 if (oldstate == MS_UNLOADED)
 280                         tape_med_state_work(device, MS_LOADED);
 281                 break;
 282         default:
 283                 break;
 284         }
 285         wake_up(&device->state_change_wq);
 286 }
 287
 288 /*
 289  * Stop running ccw. Has to be called with the device lock held.
 290  */
 291 static int
 292 __tape_cancel_io(struct tape_device *device, struct tape_request *request)
 293 {
 294         int retries;
 295         int rc;
 296
 297         /* Check if interrupt has already been processed */
 298         if (request->callback == NULL)
 299                 return 0;
 300
 301         rc = 0;
 302         for (retries = 0; retries < 5; retries++) {
 303                 rc = ccw_device_clear(device->cdev, (long) request);
 304
 305                 switch (rc) {
 306                         case 0:
 307                                 request->status = TAPE_REQUEST_DONE;
 308                                 return 0;
 309                         case -EBUSY:
 310                                 request->status = TAPE_REQUEST_CANCEL;
 311                                 schedule_delayed_work(&device->tape_dnr, 0);
 312                                 return 0;
 313                         case -ENODEV:
 314                                 DBF_EXCEPTION(2, "device gone, retry\n");
 315                                 break;
 316                         case -EIO:
 317                                 DBF_EXCEPTION(2, "I/O error, retry\n");
 318                                 break;
 319                         default:
 320                                 BUG();
 321                 }
 322         }
 323
 324         return rc;
 325 }
 326
 327 /*
 328  * Add device into the sorted list, giving it the first
 329  * available minor number.
 330  */
 331 static int
 332 tape_assign_minor(struct tape_device *device)
 333 {
 334         struct tape_device *tmp;
 335         int minor;
 336
 337         minor = 0;
 338         write_lock(&tape_device_lock);
 339         list_for_each_entry(tmp, &tape_device_list, node) {
 340                 if (minor < tmp->first_minor)
 341                         break;
 342                 minor += TAPE_MINORS_PER_DEV;
 343         }
 344         if (minor >= 256) {
 345                 write_unlock(&tape_device_lock);
 346                 return -ENODEV;
 347         }
 348         device->first_minor = minor;
 349         list_add_tail(&device->node, &tmp->node);
 350         write_unlock(&tape_device_lock);
 351         return 0;
 352 }
 353
 354 /* remove device from the list */
 355 static void
 356 tape_remove_minor(struct tape_device *device)
 357 {
 358         write_lock(&tape_device_lock);
 359         list_del_init(&device->node);
 360         device->first_minor = -1;
 361         write_unlock(&tape_device_lock);
 362 }
 363
 364 /*
 365  * Set a device online.
 366  *
 367  * This function is called by the common I/O layer to move a device from the
 368  * detected but offline into the online state.
 369  * If we return an error (RC < 0) the device remains in the offline state. This
 370  * can happen if the device is assigned somewhere else, for example.
 371  */
 372 int
 373 tape_generic_online(struct tape_device *device,
 374                    struct tape_discipline *discipline)
 375 {
 376         int rc;
 377
 378         DBF_LH(6, "tape_enable_device(%p, %p)\n", device, discipline);
 379
 380         if (device->tape_state != TS_INIT) {
 381                 DBF_LH(3, "Tapestate not INIT (%d)\n", device->tape_state);
 382                 return -EINVAL;
 383         }
 384
 385         init_timer(&device->lb_timeout);
 386         device->lb_timeout.function = tape_long_busy_timeout;
 387
 388         /* Let the discipline have a go at the device. */
 389         device->discipline = discipline;
 390         if (!try_module_get(discipline->owner)) {
 391                 return -EINVAL;
 392         }
 393
 394         rc = discipline->setup_device(device);
 395         if (rc)
 396                 goto out;
 397         rc = tape_assign_minor(device);
 398         if (rc)
 399                 goto out_discipline;
 400
 401         rc = tapechar_setup_device(device);
 402         if (rc)
 403                 goto out_minor;
 404         rc = tapeblock_setup_device(device);
 405         if (rc)
 406                 goto out_char;
 407
 408         tape_state_set(device, TS_UNUSED);
 409
 410         DBF_LH(3, "(%08x): Drive set online\n", device->cdev_id);
 411
 412         return 0;
 413
 414 out_char:
 415         tapechar_cleanup_device(device);
 416 out_minor:
 417         tape_remove_minor(device);
 418 out_discipline:
 419         device->discipline->cleanup_device(device);
 420         device->discipline = NULL;
 421 out:
 422         module_put(discipline->owner);
 423         return rc;
 424 }
 425
 426 static void
 427 tape_cleanup_device(struct tape_device *device)
 428 {
 429         tapeblock_cleanup_device(device);
 430         tapechar_cleanup_device(device);
 431         device->discipline->cleanup_device(device);
 432         module_put(device->discipline->owner);
 433         tape_remove_minor(device);
 434         tape_med_state_set(device, MS_UNKNOWN);
 435 }
 436
 437 /*
 438  * Suspend device.
 439  *
 440  * Called by the common I/O layer if the drive should be suspended on user
 441  * request. We refuse to suspend if the device is loaded or in use for the
 442  * following reason:
 443  * While the Linux guest is suspended, it might be logged off which causes
 444  * devices to be detached. Tape devices are automatically rewound and unloaded
 445  * during DETACH processing (unless the tape device was attached with the
 446  * NOASSIGN or MULTIUSER option). After rewind/unload, there is no way to
 447  * resume the original state of the tape device, since we would need to
 448  * manually re-load the cartridge which was active at suspend time.
 449  */
 450 int tape_generic_pm_suspend(struct ccw_device *cdev)
 451 {
 452         struct tape_device *device;
 453
 454         device = dev_get_drvdata(&cdev->dev);
 455         if (!device) {
 456                 return -ENODEV;
 457         }
 458
 459         DBF_LH(3, "(%08x): tape_generic_pm_suspend(%p)\n",
 460                 device->cdev_id, device);
 461
 462         if (device->medium_state != MS_UNLOADED) {
 463                 pr_err("A cartridge is loaded in tape device %s, "
 464                        "refusing to suspend\n", dev_name(&cdev->dev));
 465                 return -EBUSY;
 466         }
 467
 468         spin_lock_irq(get_ccwdev_lock(device->cdev));
 469         switch (device->tape_state) {
 470                 case TS_INIT:
 471                 case TS_NOT_OPER:
 472                 case TS_UNUSED:
 473                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 474                         break;
 475                 default:
 476                         pr_err("Tape device %s is busy, refusing to "
 477                                "suspend\n", dev_name(&cdev->dev));
 478                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 479                         return -EBUSY;
 480         }
 481
 482         DBF_LH(3, "(%08x): Drive suspended.\n", device->cdev_id);
 483         return 0;
 484 }
 485
 486 /*
 487  * Set device offline.
 488  *
 489  * Called by the common I/O layer if the drive should set offline on user
 490  * request. We may prevent this by returning an error.
 491  * Manual offline is only allowed while the drive is not in use.
 492  */
 493 int
 494 tape_generic_offline(struct ccw_device *cdev)
 495 {
 496         struct tape_device *device;
 497
 498         device = dev_get_drvdata(&cdev->dev);
 499         if (!device) {
 500                 return -ENODEV;
 501         }
 502
 503         DBF_LH(3, "(%08x): tape_generic_offline(%p)\n",
 504                 device->cdev_id, device);
 505
 506         spin_lock_irq(get_ccwdev_lock(device->cdev));
 507         switch (device->tape_state) {
 508                 case TS_INIT:
 509                 case TS_NOT_OPER:
 510                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 511                         break;
 512                 case TS_UNUSED:
 513                         tape_state_set(device, TS_INIT);
 514                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 515                         tape_cleanup_device(device);
 516                         break;
 517                 default:
 518                         DBF_EVENT(3, "(%08x): Set offline failed "
 519                                 "- drive in use.\n",
 520                                 device->cdev_id);
 521                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 522                         return -EBUSY;
 523         }
 524
 525         DBF_LH(3, "(%08x): Drive set offline.\n", device->cdev_id);
 526         return 0;
 527 }
 528
 529 /*
 530  * Allocate memory for a new device structure.
 531  */
 532 static struct tape_device *
 533 tape_alloc_device(void)
 534 {
 535         struct tape_device *device;
 536
 537         device = kzalloc(sizeof(struct tape_device), GFP_KERNEL);
 538         if (device == NULL) {
 539                 DBF_EXCEPTION(2, "ti:no mem\n");
 540                 return ERR_PTR(-ENOMEM);
 541         }
 542         device->modeset_byte = kmalloc(1, GFP_KERNEL | GFP_DMA);
 543         if (device->modeset_byte == NULL) {
 544                 DBF_EXCEPTION(2, "ti:no mem\n");
 545                 kfree(device);
 546                 return ERR_PTR(-ENOMEM);
 547         }
 548         mutex_init(&device->mutex);
 549         INIT_LIST_HEAD(&device->req_queue);
 550         INIT_LIST_HEAD(&device->node);
 551         init_waitqueue_head(&device->state_change_wq);
 552         init_waitqueue_head(&device->wait_queue);
 553         device->tape_state = TS_INIT;
 554         device->medium_state = MS_UNKNOWN;
 555         *device->modeset_byte = 0;
 556         device->first_minor = -1;
 557         atomic_set(&device->ref_count, 1);
 558         INIT_DELAYED_WORK(&device->tape_dnr, tape_delayed_next_request);
 559
 560         return device;
 561 }
 562
 563 /*
 564  * Get a reference to an existing device structure. This will automatically
 565  * increment the reference count.
 566  */
 567 struct tape_device *
 568 tape_get_device(struct tape_device *device)
 569 {
 570         int count;
 571
 572         count = atomic_inc_return(&device->ref_count);
 573         DBF_EVENT(4, "tape_get_device(%p) = %i\n", device, count);
 574         return device;
 575 }
 576
 577 /*
 578  * Decrease the reference counter of a devices structure. If the
 579  * reference counter reaches zero free the device structure.
 580  * The function returns a NULL pointer to be used by the caller
 581  * for clearing reference pointers.
 582  */
 583 void
 584 tape_put_device(struct tape_device *device)
 585 {
 586         int count;
 587
 588         count = atomic_dec_return(&device->ref_count);
 589         DBF_EVENT(4, "tape_put_device(%p) -> %i\n", device, count);
 590         BUG_ON(count < 0);
 591         if (count == 0) {
 592                 kfree(device->modeset_byte);
 593                 kfree(device);
 594         }
 595 }
 596
 597 /*
 598  * Find tape device by a device index.
 599  */
 600 struct tape_device *
 601 tape_find_device(int devindex)
 602 {
 603         struct tape_device *device, *tmp;
 604
 605         device = ERR_PTR(-ENODEV);
 606         read_lock(&tape_device_lock);
 607         list_for_each_entry(tmp, &tape_device_list, node) {
 608                 if (tmp->first_minor / TAPE_MINORS_PER_DEV == devindex) {
 609                         device = tape_get_device(tmp);
 610                         break;
 611                 }
 612         }
 613         read_unlock(&tape_device_lock);
 614         return device;
 615 }
 616
 617 /*
 618  * Driverfs tape probe function.
 619  */
 620 int
 621 tape_generic_probe(struct ccw_device *cdev)
 622 {
 623         struct tape_device *device;
 624         int ret;
 625         struct ccw_dev_id dev_id;
 626
 627         device = tape_alloc_device();
 628         if (IS_ERR(device))
 629                 return -ENODEV;
 630         ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP |
 631                                      CCWDEV_DO_MULTIPATH);
 632         ret = sysfs_create_group(&cdev->dev.kobj, &tape_attr_group);
 633         if (ret) {
 634                 tape_put_device(device);
 635                 return ret;
 636         }
 637         dev_set_drvdata(&cdev->dev, device);
 638         cdev->handler = __tape_do_irq;
 639         device->cdev = cdev;
 640         ccw_device_get_id(cdev, &dev_id);
 641         device->cdev_id = devid_to_int(&dev_id);
 642         return ret;
 643 }
 644
 645 static void
 646 __tape_discard_requests(struct tape_device *device)
 647 {
 648         struct tape_request *   request;
 649         struct list_head *      l, *n;
 650
 651         list_for_each_safe(l, n, &device->req_queue) {
 652                 request = list_entry(l, struct tape_request, list);
 653                 if (request->status == TAPE_REQUEST_IN_IO)
 654                         request->status = TAPE_REQUEST_DONE;
 655                 list_del(&request->list);
 656
 657                 /* Decrease ref_count for removed request. */
 658                 request->device = NULL;
 659                 tape_put_device(device);
 660                 request->rc = -EIO;
 661                 if (request->callback != NULL)
 662                         request->callback(request, request->callback_data);
 663         }
 664 }
 665
 666 /*
 667  * Driverfs tape remove function.
 668  *
 669  * This function is called whenever the common I/O layer detects the device
 670  * gone. This can happen at any time and we cannot refuse.
 671  */
 672 void
 673 tape_generic_remove(struct ccw_device *cdev)
 674 {
 675         struct tape_device *    device;
 676
 677         device = dev_get_drvdata(&cdev->dev);
 678         if (!device) {
 679                 return;
 680         }
 681         DBF_LH(3, "(%08x): tape_generic_remove(%p)\n", device->cdev_id, cdev);
 682
 683         spin_lock_irq(get_ccwdev_lock(device->cdev));
 684         switch (device->tape_state) {
 685                 case TS_INIT:
 686                         tape_state_set(device, TS_NOT_OPER);
 687                 case TS_NOT_OPER:
 688                         /*
 689                          * Nothing to do.
 690                          */
 691                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 692                         break;
 693                 case TS_UNUSED:
 694                         /*
 695                          * Need only to release the device.
 696                          */
 697                         tape_state_set(device, TS_NOT_OPER);
 698                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 699                         tape_cleanup_device(device);
 700                         break;
 701                 default:
 702                         /*
 703                          * There may be requests on the queue. We will not get
 704                          * an interrupt for a request that was running. So we
 705                          * just post them all as I/O errors.
 706                          */
 707                         DBF_EVENT(3, "(%08x): Drive in use vanished!\n",
 708                                 device->cdev_id);
 709                         pr_warning("%s: A tape unit was detached while in "
 710                                    "use\n", dev_name(&device->cdev->dev));
 711                         tape_state_set(device, TS_NOT_OPER);
 712                         __tape_discard_requests(device);
 713                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 714                         tape_cleanup_device(device);
 715         }
 716
 717         device = dev_get_drvdata(&cdev->dev);
 718         if (device) {
 719                 sysfs_remove_group(&cdev->dev.kobj, &tape_attr_group);
 720                 dev_set_drvdata(&cdev->dev, NULL);
 721                 tape_put_device(device);
 722         }
 723 }
 724
 725 /*
 726  * Allocate a new tape ccw request
 727  */
 728 struct tape_request *
 729 tape_alloc_request(int cplength, int datasize)
 730 {
 731         struct tape_request *request;
 732
 733         BUG_ON(datasize > PAGE_SIZE || (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
 734
 735         DBF_LH(6, "tape_alloc_request(%d, %d)\n", cplength, datasize);
 736
 737         request = kzalloc(sizeof(struct tape_request), GFP_KERNEL);
 738         if (request == NULL) {
 739                 DBF_EXCEPTION(1, "cqra nomem\n");
 740                 return ERR_PTR(-ENOMEM);
 741         }
 742         /* allocate channel program */
 743         if (cplength > 0) {
 744                 request->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
 745                                           GFP_ATOMIC | GFP_DMA);
 746                 if (request->cpaddr == NULL) {
 747                         DBF_EXCEPTION(1, "cqra nomem\n");
 748                         kfree(request);
 749                         return ERR_PTR(-ENOMEM);
 750                 }
 751         }
 752         /* alloc small kernel buffer */
 753         if (datasize > 0) {
 754                 request->cpdata = kzalloc(datasize, GFP_KERNEL | GFP_DMA);
 755                 if (request->cpdata == NULL) {
 756                         DBF_EXCEPTION(1, "cqra nomem\n");
 757                         kfree(request->cpaddr);
 758                         kfree(request);
 759                         return ERR_PTR(-ENOMEM);
 760                 }
 761         }
 762         DBF_LH(6, "New request %p(%p/%p)\n", request, request->cpaddr,
 763                 request->cpdata);
 764
 765         return request;
 766 }
 767
 768 /*
 769  * Free tape ccw request
 770  */
 771 void
 772 tape_free_request (struct tape_request * request)
 773 {
 774         DBF_LH(6, "Free request %p\n", request);
 775
 776         if (request->device)
 777                 tape_put_device(request->device);
 778         kfree(request->cpdata);
 779         kfree(request->cpaddr);
 780         kfree(request);
 781 }
 782
 783 static int
 784 __tape_start_io(struct tape_device *device, struct tape_request *request)
 785 {
 786         int rc;
 787
 788 #ifdef CONFIG_S390_TAPE_BLOCK
 789         if (request->op == TO_BLOCK)
 790                 device->discipline->check_locate(device, request);
 791 #endif
 792         rc = ccw_device_start(
 793                 device->cdev,
 794                 request->cpaddr,
 795                 (unsigned long) request,
 796                 0x00,
 797                 request->options
 798         );
 799         if (rc == 0) {
 800                 request->status = TAPE_REQUEST_IN_IO;
 801         } else if (rc == -EBUSY) {
 802                 /* The common I/O subsystem is currently busy. Retry later. */
 803                 request->status = TAPE_REQUEST_QUEUED;
 804                 schedule_delayed_work(&device->tape_dnr, 0);
 805                 rc = 0;
 806         } else {
 807                 /* Start failed. Remove request and indicate failure. */
 808                 DBF_EVENT(1, "tape: start request failed with RC = %i\n", rc);
 809         }
 810         return rc;
 811 }
 812
 813 static void
 814 __tape_start_next_request(struct tape_device *device)
 815 {
 816         struct list_head *l, *n;
 817         struct tape_request *request;
 818         int rc;
 819
 820         DBF_LH(6, "__tape_start_next_request(%p)\n", device);
 821         /*
 822          * Try to start each request on request queue until one is
 823          * started successful.
 824          */
 825         list_for_each_safe(l, n, &device->req_queue) {
 826                 request = list_entry(l, struct tape_request, list);
 827
 828                 /*
 829                  * Avoid race condition if bottom-half was triggered more than
 830                  * once.
 831                  */
 832                 if (request->status == TAPE_REQUEST_IN_IO)
 833                         return;
 834                 /*
 835                  * Request has already been stopped. We have to wait until
 836                  * the request is removed from the queue in the interrupt
 837                  * handling.
 838                  */
 839                 if (request->status == TAPE_REQUEST_DONE)
 840                         return;
 841
 842                 /*
 843                  * We wanted to cancel the request but the common I/O layer
 844                  * was busy at that time. This can only happen if this
 845                  * function is called by delayed_next_request.
 846                  * Otherwise we start the next request on the queue.
 847                  */
 848                 if (request->status == TAPE_REQUEST_CANCEL) {
 849                         rc = __tape_cancel_io(device, request);
 850                 } else {
 851                         rc = __tape_start_io(device, request);
 852                 }
 853                 if (rc == 0)
 854                         return;
 855
 856                 /* Set ending status. */
 857                 request->rc = rc;
 858                 request->status = TAPE_REQUEST_DONE;
 859
 860                 /* Remove from request queue. */
 861                 list_del(&request->list);
 862
 863                 /* Do callback. */
 864                 if (request->callback != NULL)
 865                         request->callback(request, request->callback_data);
 866         }
 867 }
 868
 869 static void
 870 tape_delayed_next_request(struct work_struct *work)
 871 {
 872         struct tape_device *device =
 873                 container_of(work, struct tape_device, tape_dnr.work);
 874
 875         DBF_LH(6, "tape_delayed_next_request(%p)\n", device);
 876         spin_lock_irq(get_ccwdev_lock(device->cdev));
 877         __tape_start_next_request(device);
 878         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 879 }
 880
 881 static void tape_long_busy_timeout(unsigned long data)
 882 {
 883         struct tape_request *request;
 884         struct tape_device *device;
 885
 886         device = (struct tape_device *) data;
 887         spin_lock_irq(get_ccwdev_lock(device->cdev));
 888         request = list_entry(device->req_queue.next, struct tape_request, list);
 889         BUG_ON(request->status != TAPE_REQUEST_LONG_BUSY);
 890         DBF_LH(6, "%08x: Long busy timeout.\n", device->cdev_id);
 891         __tape_start_next_request(device);
 892         device->lb_timeout.data = 0UL;
 893         tape_put_device(device);
 894         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 895 }
 896
 897 static void
 898 __tape_end_request(
 899         struct tape_device *    device,
 900         struct tape_request *   request,
 901         int                     rc)
 902 {
 903         DBF_LH(6, "__tape_end_request(%p, %p, %i)\n", device, request, rc);
 904         if (request) {
 905                 request->rc = rc;
 906                 request->status = TAPE_REQUEST_DONE;
 907
 908                 /* Remove from request queue. */
 909                 list_del(&request->list);
 910
 911                 /* Do callback. */
 912                 if (request->callback != NULL)
 913                         request->callback(request, request->callback_data);
 914         }
 915
 916         /* Start next request. */
 917         if (!list_empty(&device->req_queue))
 918                 __tape_start_next_request(device);
 919 }
 920
 921 /*
 922  * Write sense data to dbf
 923  */
 924 void
 925 tape_dump_sense_dbf(struct tape_device *device, struct tape_request *request,
 926                     struct irb *irb)
 927 {
 928         unsigned int *sptr;
 929         const char* op;
 930
 931         if (request != NULL)
 932                 op = tape_op_verbose[request->op];
 933         else
 934                 op = "---";
 935         DBF_EVENT(3, "DSTAT : %02x   CSTAT: %02x\n",
 936                   irb->scsw.cmd.dstat, irb->scsw.cmd.cstat);
 937         DBF_EVENT(3, "DEVICE: %08x OP\t: %s\n", device->cdev_id, op);
 938         sptr = (unsigned int *) irb->ecw;
 939         DBF_EVENT(3, "%08x %08x\n", sptr[0], sptr[1]);
 940         DBF_EVENT(3, "%08x %08x\n", sptr[2], sptr[3]);
 941         DBF_EVENT(3, "%08x %08x\n", sptr[4], sptr[5]);
 942         DBF_EVENT(3, "%08x %08x\n", sptr[6], sptr[7]);
 943 }
 944
 945 /*
 946  * I/O helper function. Adds the request to the request queue
 947  * and starts it if the tape is idle. Has to be called with
 948  * the device lock held.
 949  */
 950 static int
 951 __tape_start_request(struct tape_device *device, struct tape_request *request)
 952 {
 953         int rc;
 954
 955         switch (request->op) {
 956                 case TO_MSEN:
 957                 case TO_ASSIGN:
 958                 case TO_UNASSIGN:
 959                 case TO_READ_ATTMSG:
 960                 case TO_RDC:
 961                         if (device->tape_state == TS_INIT)
 962                                 break;
 963                         if (device->tape_state == TS_UNUSED)
 964                                 break;
 965                 default:
 966                         if (device->tape_state == TS_BLKUSE)
 967                                 break;
 968                         if (device->tape_state != TS_IN_USE)
 969                                 return -ENODEV;
 970         }
 971
 972         /* Increase use count of device for the added request. */
 973         request->device = tape_get_device(device);
 974
 975         if (list_empty(&device->req_queue)) {
 976                 /* No other requests are on the queue. Start this one. */
 977                 rc = __tape_start_io(device, request);
 978                 if (rc)
 979                         return rc;
 980
 981                 DBF_LH(5, "Request %p added for execution.\n", request);
 982                 list_add(&request->list, &device->req_queue);
 983         } else {
 984                 DBF_LH(5, "Request %p add to queue.\n", request);
 985                 request->status = TAPE_REQUEST_QUEUED;
 986                 list_add_tail(&request->list, &device->req_queue);
 987         }
 988         return 0;
 989 }
 990
 991 /*
 992  * Add the request to the request queue, try to start it if the
 993  * tape is idle. Return without waiting for end of i/o.
 994  */
 995 int
 996 tape_do_io_async(struct tape_device *device, struct tape_request *request)
 997 {
 998         int rc;
 999
1000         DBF_LH(6, "tape_do_io_async(%p, %p)\n", device, request);
1001
1002         spin_lock_irq(get_ccwdev_lock(device->cdev));
1003         /* Add request to request queue and try to start it. */
1004         rc = __tape_start_request(device, request);
1005         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1006         return rc;
1007 }
1008
1009 /*
1010  * tape_do_io/__tape_wake_up
1011  * Add the request to the request queue, try to start it if the
1012  * tape is idle and wait uninterruptible for its completion.
1013  */
1014 static void
1015 __tape_wake_up(struct tape_request *request, void *data)
1016 {
1017         request->callback = NULL;
1018         wake_up((wait_queue_head_t *) data);
1019 }
1020
1021 int
1022 tape_do_io(struct tape_device *device, struct tape_request *request)
1023 {
1024         int rc;
1025
1026         spin_lock_irq(get_ccwdev_lock(device->cdev));
1027         /* Setup callback */
1028         request->callback = __tape_wake_up;
1029         request->callback_data = &device->wait_queue;
1030         /* Add request to request queue and try to start it. */
1031         rc = __tape_start_request(device, request);
1032         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1033         if (rc)
1034                 return rc;
1035         /* Request added to the queue. Wait for its completion. */
1036         wait_event(device->wait_queue, (request->callback == NULL));
1037         /* Get rc from request */
1038         return request->rc;
1039 }
1040
1041 /*
1042  * tape_do_io_interruptible/__tape_wake_up_interruptible
1043  * Add the request to the request queue, try to start it if the
1044  * tape is idle and wait uninterruptible for its completion.
1045  */
1046 static void
1047 __tape_wake_up_interruptible(struct tape_request *request, void *data)
1048 {
1049         request->callback = NULL;
1050         wake_up_interruptible((wait_queue_head_t *) data);
1051 }
1052
1053 int
1054 tape_do_io_interruptible(struct tape_device *device,
1055                          struct tape_request *request)
1056 {
1057         int rc;
1058
1059         spin_lock_irq(get_ccwdev_lock(device->cdev));
1060         /* Setup callback */
1061         request->callback = __tape_wake_up_interruptible;
1062         request->callback_data = &device->wait_queue;
1063         rc = __tape_start_request(device, request);
1064         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1065         if (rc)
1066                 return rc;
1067         /* Request added to the queue. Wait for its completion. */
1068         rc = wait_event_interruptible(device->wait_queue,
1069                                       (request->callback == NULL));
1070         if (rc != -ERESTARTSYS)
1071                 /* Request finished normally. */
1072                 return request->rc;
1073
1074         /* Interrupted by a signal. We have to stop the current request. */
1075         spin_lock_irq(get_ccwdev_lock(device->cdev));
1076         rc = __tape_cancel_io(device, request);
1077         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1078         if (rc == 0) {
1079                 /* Wait for the interrupt that acknowledges the halt. */
1080                 do {
1081                         rc = wait_event_interruptible(
1082                                 device->wait_queue,
1083                                 (request->callback == NULL)
1084                         );
1085                 } while (rc == -ERESTARTSYS);
1086
1087                 DBF_EVENT(3, "IO stopped on %08x\n", device->cdev_id);
1088                 rc = -ERESTARTSYS;
1089         }
1090         return rc;
1091 }
1092
1093 /*
1094  * Stop running ccw.
1095  */
1096 int
1097 tape_cancel_io(struct tape_device *device, struct tape_request *request)
1098 {
1099         int rc;
1100
1101         spin_lock_irq(get_ccwdev_lock(device->cdev));
1102         rc = __tape_cancel_io(device, request);
1103         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1104         return rc;
1105 }
1106
1107 /*
1108  * Tape interrupt routine, called from the ccw_device layer
1109  */
1110 static void
1111 __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
1112 {
1113         struct tape_device *device;
1114         struct tape_request *request;
1115         int rc;
1116
1117         device = dev_get_drvdata(&cdev->dev);
1118         if (device == NULL) {
1119                 return;
1120         }
1121         request = (struct tape_request *) intparm;
1122
1123         DBF_LH(6, "__tape_do_irq(device=%p, request=%p)\n", device, request);
1124
1125         /* On special conditions irb is an error pointer */
1126         if (IS_ERR(irb)) {
1127                 /* FIXME: What to do with the request? */
1128                 switch (PTR_ERR(irb)) {
1129                         case -ETIMEDOUT:
1130                                 DBF_LH(1, "(%08x): Request timed out\n",
1131                                        device->cdev_id);
1132                         case -EIO:
1133                                 __tape_end_request(device, request, -EIO);
1134                                 break;
1135                         default:
1136                                 DBF_LH(1, "(%08x): Unexpected i/o error %li\n",
1137                                        device->cdev_id, PTR_ERR(irb));
1138                 }
1139                 return;
1140         }
1141
1142         /*
1143          * If the condition code is not zero and the start function bit is
1144          * still set, this is an deferred error and the last start I/O did
1145          * not succeed. At this point the condition that caused the deferred
1146          * error might still apply. So we just schedule the request to be
1147          * started later.
1148          */
1149         if (irb->scsw.cmd.cc != 0 &&
1150             (irb->scsw.cmd.fctl & SCSW_FCTL_START_FUNC) &&
1151             (request->status == TAPE_REQUEST_IN_IO)) {
1152                 DBF_EVENT(3,"(%08x): deferred cc=%i, fctl=%i. restarting\n",
1153                         device->cdev_id, irb->scsw.cmd.cc, irb->scsw.cmd.fctl);
1154                 request->status = TAPE_REQUEST_QUEUED;
1155                 schedule_delayed_work(&device->tape_dnr, HZ);
1156                 return;
1157         }
1158
1159         /* May be an unsolicited irq */
1160         if(request != NULL)
1161                 request->rescnt = irb->scsw.cmd.count;
1162         else if ((irb->scsw.cmd.dstat == 0x85 || irb->scsw.cmd.dstat == 0x80) &&
1163                  !list_empty(&device->req_queue)) {
1164                 /* Not Ready to Ready after long busy ? */
1165                 struct tape_request *req;
1166                 req = list_entry(device->req_queue.next,
1167                                  struct tape_request, list);
1168                 if (req->status == TAPE_REQUEST_LONG_BUSY) {
1169                         DBF_EVENT(3, "(%08x): del timer\n", device->cdev_id);
1170                         if (del_timer(&device->lb_timeout)) {
1171                                 device->lb_timeout.data = 0UL;
1172                                 tape_put_device(device);
1173                                 __tape_start_next_request(device);
1174                         }
1175                         return;
1176                 }
1177         }
1178         if (irb->scsw.cmd.dstat != 0x0c) {
1179                 /* Set the 'ONLINE' flag depending on sense byte 1 */
1180                 if(*(((__u8 *) irb->ecw) + 1) & SENSE_DRIVE_ONLINE)
1181                         device->tape_generic_status |= GMT_ONLINE(~0);
1182                 else
1183                         device->tape_generic_status &= ~GMT_ONLINE(~0);
1184
1185                 /*
1186                  * Any request that does not come back with channel end
1187                  * and device end is unusual. Log the sense data.
1188                  */
1189                 DBF_EVENT(3,"-- Tape Interrupthandler --\n");
1190                 tape_dump_sense_dbf(device, request, irb);
1191         } else {
1192                 /* Upon normal completion the device _is_ online */
1193                 device->tape_generic_status |= GMT_ONLINE(~0);
1194         }
1195         if (device->tape_state == TS_NOT_OPER) {
1196                 DBF_EVENT(6, "tape:device is not operational\n");
1197                 return;
1198         }
1199
1200         /*
1201          * Request that were canceled still come back with an interrupt.
1202          * To detect these request the state will be set to TAPE_REQUEST_DONE.
1203          */
1204         if(request != NULL && request->status == TAPE_REQUEST_DONE) {
1205                 __tape_end_request(device, request, -EIO);
1206                 return;
1207         }
1208
1209         rc = device->discipline->irq(device, request, irb);
1210         /*
1211          * rc < 0 : request finished unsuccessfully.
1212          * rc == TAPE_IO_SUCCESS: request finished successfully.
1213          * rc == TAPE_IO_PENDING: request is still running. Ignore rc.
1214          * rc == TAPE_IO_RETRY: request finished but needs another go.
1215          * rc == TAPE_IO_STOP: request needs to get terminated.
1216          */
1217         switch (rc) {
1218                 case TAPE_IO_SUCCESS:
1219                         /* Upon normal completion the device _is_ online */
1220                         device->tape_generic_status |= GMT_ONLINE(~0);
1221                         __tape_end_request(device, request, rc);
1222                         break;
1223                 case TAPE_IO_PENDING:
1224                         break;
1225                 case TAPE_IO_LONG_BUSY:
1226                         device->lb_timeout.data =
1227                                 (unsigned long) tape_get_device(device);
1228                         device->lb_timeout.expires = jiffies +
1229                                 LONG_BUSY_TIMEOUT * HZ;
1230                         DBF_EVENT(3, "(%08x): add timer\n", device->cdev_id);
1231                         add_timer(&device->lb_timeout);
1232                         request->status = TAPE_REQUEST_LONG_BUSY;
1233                         break;
1234                 case TAPE_IO_RETRY:
1235                         rc = __tape_start_io(device, request);
1236                         if (rc)
1237                                 __tape_end_request(device, request, rc);
1238                         break;
1239                 case TAPE_IO_STOP:
1240                         rc = __tape_cancel_io(device, request);
1241                         if (rc)
1242                                 __tape_end_request(device, request, rc);
1243                         break;
1244                 default:
1245                         if (rc > 0) {
1246                                 DBF_EVENT(6, "xunknownrc\n");
1247                                 __tape_end_request(device, request, -EIO);
1248                         } else {
1249                                 __tape_end_request(device, request, rc);
1250                         }
1251                         break;
1252         }
1253 }
1254
1255 /*
1256  * Tape device open function used by tape_char & tape_block frontends.
1257  */
1258 int
1259 tape_open(struct tape_device *device)
1260 {
1261         int rc;
1262
1263         spin_lock_irq(get_ccwdev_lock(device->cdev));
1264         if (device->tape_state == TS_NOT_OPER) {
1265                 DBF_EVENT(6, "TAPE:nodev\n");
1266                 rc = -ENODEV;
1267         } else if (device->tape_state == TS_IN_USE) {
1268                 DBF_EVENT(6, "TAPE:dbusy\n");
1269                 rc = -EBUSY;
1270         } else if (device->tape_state == TS_BLKUSE) {
1271                 DBF_EVENT(6, "TAPE:dbusy\n");
1272                 rc = -EBUSY;
1273         } else if (device->discipline != NULL &&
1274                    !try_module_get(device->discipline->owner)) {
1275                 DBF_EVENT(6, "TAPE:nodisc\n");
1276                 rc = -ENODEV;
1277         } else {
1278                 tape_state_set(device, TS_IN_USE);
1279                 rc = 0;
1280         }
1281         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1282         return rc;
1283 }
1284
1285 /*
1286  * Tape device release function used by tape_char & tape_block frontends.
1287  */
1288 int
1289 tape_release(struct tape_device *device)
1290 {
1291         spin_lock_irq(get_ccwdev_lock(device->cdev));
1292         if (device->tape_state == TS_IN_USE)
1293                 tape_state_set(device, TS_UNUSED);
1294         module_put(device->discipline->owner);
1295         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1296         return 0;
1297 }
1298
1299 /*
1300  * Execute a magnetic tape command a number of times.
1301  */
1302 int
1303 tape_mtop(struct tape_device *device, int mt_op, int mt_count)
1304 {
1305         tape_mtop_fn fn;
1306         int rc;
1307
1308         DBF_EVENT(6, "TAPE:mtio\n");
1309         DBF_EVENT(6, "TAPE:ioop: %x\n", mt_op);
1310         DBF_EVENT(6, "TAPE:arg:  %x\n", mt_count);
1311
1312         if (mt_op < 0 || mt_op >= TAPE_NR_MTOPS)
1313                 return -EINVAL;
1314         fn = device->discipline->mtop_array[mt_op];
1315         if (fn == NULL)
1316                 return -EINVAL;
1317
1318         /* We assume that the backends can handle count up to 500. */
1319         if (mt_op == MTBSR  || mt_op == MTFSR  || mt_op == MTFSF  ||
1320             mt_op == MTBSF  || mt_op == MTFSFM || mt_op == MTBSFM) {
1321                 rc = 0;
1322                 for (; mt_count > 500; mt_count -= 500)
1323                         if ((rc = fn(device, 500)) != 0)
1324                                 break;
1325                 if (rc == 0)
1326                         rc = fn(device, mt_count);
1327         } else
1328                 rc = fn(device, mt_count);
1329         return rc;
1330
1331 }
1332
1333 /*
1334  * Tape init function.
1335  */
1336 static int
1337 tape_init (void)
1338 {
1339         TAPE_DBF_AREA = debug_register ( "tape", 2, 2, 4*sizeof(long));
1340         debug_register_view(TAPE_DBF_AREA, &debug_sprintf_view);
1341 #ifdef DBF_LIKE_HELL
1342         debug_set_level(TAPE_DBF_AREA, 6);
1343 #endif
1344         DBF_EVENT(3, "tape init\n");
1345         tape_proc_init();
1346         tapechar_init ();
1347         tapeblock_init ();
1348         return 0;
1349 }
1350
1351 /*
1352  * Tape exit function.
1353  */
1354 static void
1355 tape_exit(void)
1356 {
1357         DBF_EVENT(6, "tape exit\n");
1358
1359         /* Get rid of the frontends */
1360         tapechar_exit();
1361         tapeblock_exit();
1362         tape_proc_cleanup();
1363         debug_unregister (TAPE_DBF_AREA);
1364 }
1365
1366 MODULE_AUTHOR("(C) 2001 IBM Deutschland Entwicklung GmbH by Carsten Otte and "
1367               "Michael Holzheu (cotte@de.ibm.com,holzheu@de.ibm.com)");
1368 MODULE_DESCRIPTION("Linux on zSeries channel attached tape device driver");
1369 MODULE_LICENSE("GPL");
1370
1371 module_init(tape_init);
1372 module_exit(tape_exit);
1373
1374 EXPORT_SYMBOL(tape_generic_remove);
1375 EXPORT_SYMBOL(tape_generic_probe);
1376 EXPORT_SYMBOL(tape_generic_online);
1377 EXPORT_SYMBOL(tape_generic_offline);
1378 EXPORT_SYMBOL(tape_generic_pm_suspend);
1379 EXPORT_SYMBOL(tape_put_device);
1380 EXPORT_SYMBOL(tape_get_device);
1381 EXPORT_SYMBOL(tape_state_verbose);
1382 EXPORT_SYMBOL(tape_op_verbose);
1383 EXPORT_SYMBOL(tape_state_set);
1384 EXPORT_SYMBOL(tape_med_state_set);
1385 EXPORT_SYMBOL(tape_alloc_request);
1386 EXPORT_SYMBOL(tape_free_request);
1387 EXPORT_SYMBOL(tape_dump_sense_dbf);
1388 EXPORT_SYMBOL(tape_do_io);
1389 EXPORT_SYMBOL(tape_do_io_async);
1390 EXPORT_SYMBOL(tape_do_io_interruptible);
1391 EXPORT_SYMBOL(tape_cancel_io);
1392 EXPORT_SYMBOL(tape_mtop);