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