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. 2001,2006
   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 #include <linux/module.h>
  15 #include <linux/init.h>      // for kernel parameters
  16 #include <linux/kmod.h>      // for requesting modules
  17 #include <linux/spinlock.h>  // for locks
  18 #include <linux/vmalloc.h>
  19 #include <linux/list.h>
  20
  21 #include <asm/types.h>       // for variable types
  22
  23 #define TAPE_DBF_AREA   tape_core_dbf
  24
  25 #include "tape.h"
  26 #include "tape_std.h"
  27
  28 #define PRINTK_HEADER "TAPE_CORE: "
  29 #define LONG_BUSY_TIMEOUT 180 /* seconds */
  30
  31 static void __tape_do_irq (struct ccw_device *, unsigned long, struct irb *);
  32 static void tape_delayed_next_request(struct work_struct *);
  33 static void tape_long_busy_timeout(unsigned long data);
  34
  35 /*
  36  * One list to contain all tape devices of all disciplines, so
  37  * we can assign the devices to minor numbers of the same major
  38  * The list is protected by the rwlock
  39  */
  40 static LIST_HEAD(tape_device_list);
  41 static DEFINE_RWLOCK(tape_device_lock);
  42
  43 /*
  44  * Pointer to debug area.
  45  */
  46 debug_info_t *TAPE_DBF_AREA = NULL;
  47 EXPORT_SYMBOL(TAPE_DBF_AREA);
  48
  49 /*
  50  * Printable strings for tape enumerations.
  51  */
  52 const char *tape_state_verbose[TS_SIZE] =
  53 {
  54         [TS_UNUSED]   = "UNUSED",
  55         [TS_IN_USE]   = "IN_USE",
  56         [TS_BLKUSE]   = "BLKUSE",
  57         [TS_INIT]     = "INIT  ",
  58         [TS_NOT_OPER] = "NOT_OP"
  59 };
  60
  61 const char *tape_op_verbose[TO_SIZE] =
  62 {
  63         [TO_BLOCK] = "BLK",     [TO_BSB] = "BSB",
  64         [TO_BSF] = "BSF",       [TO_DSE] = "DSE",
  65         [TO_FSB] = "FSB",       [TO_FSF] = "FSF",
  66         [TO_LBL] = "LBL",       [TO_NOP] = "NOP",
  67         [TO_RBA] = "RBA",       [TO_RBI] = "RBI",
  68         [TO_RFO] = "RFO",       [TO_REW] = "REW",
  69         [TO_RUN] = "RUN",       [TO_WRI] = "WRI",
  70         [TO_WTM] = "WTM",       [TO_MSEN] = "MSN",
  71         [TO_LOAD] = "LOA",      [TO_READ_CONFIG] = "RCF",
  72         [TO_READ_ATTMSG] = "RAT",
  73         [TO_DIS] = "DIS",       [TO_ASSIGN] = "ASS",
  74         [TO_UNASSIGN] = "UAS",  [TO_CRYPT_ON] = "CON",
  75         [TO_CRYPT_OFF] = "COF", [TO_KEKL_SET] = "KLS",
  76         [TO_KEKL_QUERY] = "KLQ",[TO_RDC] = "RDC",
  77 };
  78
  79 static int devid_to_int(struct ccw_dev_id *dev_id)
  80 {
  81         return dev_id->devno + (dev_id->ssid << 16);
  82 }
  83
  84 /*
  85  * Some channel attached tape specific attributes.
  86  *
  87  * FIXME: In the future the first_minor and blocksize attribute should be
  88  *        replaced by a link to the cdev tree.
  89  */
  90 static ssize_t
  91 tape_medium_state_show(struct device *dev, struct device_attribute *attr, char *buf)
  92 {
  93         struct tape_device *tdev;
  94
  95         tdev = (struct tape_device *) dev->driver_data;
  96         return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->medium_state);
  97 }
  98
  99 static
 100 DEVICE_ATTR(medium_state, 0444, tape_medium_state_show, NULL);
 101
 102 static ssize_t
 103 tape_first_minor_show(struct device *dev, struct device_attribute *attr, char *buf)
 104 {
 105         struct tape_device *tdev;
 106
 107         tdev = (struct tape_device *) dev->driver_data;
 108         return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->first_minor);
 109 }
 110
 111 static
 112 DEVICE_ATTR(first_minor, 0444, tape_first_minor_show, NULL);
 113
 114 static ssize_t
 115 tape_state_show(struct device *dev, struct device_attribute *attr, char *buf)
 116 {
 117         struct tape_device *tdev;
 118
 119         tdev = (struct tape_device *) dev->driver_data;
 120         return scnprintf(buf, PAGE_SIZE, "%s\n", (tdev->first_minor < 0) ?
 121                 "OFFLINE" : tape_state_verbose[tdev->tape_state]);
 122 }
 123
 124 static
 125 DEVICE_ATTR(state, 0444, tape_state_show, NULL);
 126
 127 static ssize_t
 128 tape_operation_show(struct device *dev, struct device_attribute *attr, char *buf)
 129 {
 130         struct tape_device *tdev;
 131         ssize_t rc;
 132
 133         tdev = (struct tape_device *) dev->driver_data;
 134         if (tdev->first_minor < 0)
 135                 return scnprintf(buf, PAGE_SIZE, "N/A\n");
 136
 137         spin_lock_irq(get_ccwdev_lock(tdev->cdev));
 138         if (list_empty(&tdev->req_queue))
 139                 rc = scnprintf(buf, PAGE_SIZE, "---\n");
 140         else {
 141                 struct tape_request *req;
 142
 143                 req = list_entry(tdev->req_queue.next, struct tape_request,
 144                         list);
 145                 rc = scnprintf(buf,PAGE_SIZE, "%s\n", tape_op_verbose[req->op]);
 146         }
 147         spin_unlock_irq(get_ccwdev_lock(tdev->cdev));
 148         return rc;
 149 }
 150
 151 static
 152 DEVICE_ATTR(operation, 0444, tape_operation_show, NULL);
 153
 154 static ssize_t
 155 tape_blocksize_show(struct device *dev, struct device_attribute *attr, char *buf)
 156 {
 157         struct tape_device *tdev;
 158
 159         tdev = (struct tape_device *) dev->driver_data;
 160
 161         return scnprintf(buf, PAGE_SIZE, "%i\n", tdev->char_data.block_size);
 162 }
 163
 164 static
 165 DEVICE_ATTR(blocksize, 0444, tape_blocksize_show, NULL);
 166
 167 static struct attribute *tape_attrs[] = {
 168         &dev_attr_medium_state.attr,
 169         &dev_attr_first_minor.attr,
 170         &dev_attr_state.attr,
 171         &dev_attr_operation.attr,
 172         &dev_attr_blocksize.attr,
 173         NULL
 174 };
 175
 176 static struct attribute_group tape_attr_group = {
 177         .attrs = tape_attrs,
 178 };
 179
 180 /*
 181  * Tape state functions
 182  */
 183 void
 184 tape_state_set(struct tape_device *device, enum tape_state newstate)
 185 {
 186         const char *str;
 187
 188         if (device->tape_state == TS_NOT_OPER) {
 189                 DBF_EVENT(3, "ts_set err: not oper\n");
 190                 return;
 191         }
 192         DBF_EVENT(4, "ts. dev:  %x\n", device->first_minor);
 193         DBF_EVENT(4, "old ts:\t\n");
 194         if (device->tape_state < TS_SIZE && device->tape_state >=0 )
 195                 str = tape_state_verbose[device->tape_state];
 196         else
 197                 str = "UNKNOWN TS";
 198         DBF_EVENT(4, "%s\n", str);
 199         DBF_EVENT(4, "new ts:\t\n");
 200         if (newstate < TS_SIZE && newstate >= 0)
 201                 str = tape_state_verbose[newstate];
 202         else
 203                 str = "UNKNOWN TS";
 204         DBF_EVENT(4, "%s\n", str);
 205         device->tape_state = newstate;
 206         wake_up(&device->state_change_wq);
 207 }
 208
 209 void
 210 tape_med_state_set(struct tape_device *device, enum tape_medium_state newstate)
 211 {
 212         if (device->medium_state == newstate)
 213                 return;
 214         switch(newstate){
 215         case MS_UNLOADED:
 216                 device->tape_generic_status |= GMT_DR_OPEN(~0);
 217                 PRINT_INFO("(%s): Tape is unloaded\n",
 218                            device->cdev->dev.bus_id);
 219                 break;
 220         case MS_LOADED:
 221                 device->tape_generic_status &= ~GMT_DR_OPEN(~0);
 222                 PRINT_INFO("(%s): Tape has been mounted\n",
 223                            device->cdev->dev.bus_id);
 224                 break;
 225         default:
 226                 // print nothing
 227                 break;
 228         }
 229         device->medium_state = newstate;
 230         wake_up(&device->state_change_wq);
 231 }
 232
 233 /*
 234  * Stop running ccw. Has to be called with the device lock held.
 235  */
 236 static int
 237 __tape_cancel_io(struct tape_device *device, struct tape_request *request)
 238 {
 239         int retries;
 240         int rc;
 241
 242         /* Check if interrupt has already been processed */
 243         if (request->callback == NULL)
 244                 return 0;
 245
 246         rc = 0;
 247         for (retries = 0; retries < 5; retries++) {
 248                 rc = ccw_device_clear(device->cdev, (long) request);
 249
 250                 switch (rc) {
 251                         case 0:
 252                                 request->status = TAPE_REQUEST_DONE;
 253                                 return 0;
 254                         case -EBUSY:
 255                                 request->status = TAPE_REQUEST_CANCEL;
 256                                 schedule_delayed_work(&device->tape_dnr, 0);
 257                                 return 0;
 258                         case -ENODEV:
 259                                 DBF_EXCEPTION(2, "device gone, retry\n");
 260                                 break;
 261                         case -EIO:
 262                                 DBF_EXCEPTION(2, "I/O error, retry\n");
 263                                 break;
 264                         default:
 265                                 BUG();
 266                 }
 267         }
 268
 269         return rc;
 270 }
 271
 272 /*
 273  * Add device into the sorted list, giving it the first
 274  * available minor number.
 275  */
 276 static int
 277 tape_assign_minor(struct tape_device *device)
 278 {
 279         struct tape_device *tmp;
 280         int minor;
 281
 282         minor = 0;
 283         write_lock(&tape_device_lock);
 284         list_for_each_entry(tmp, &tape_device_list, node) {
 285                 if (minor < tmp->first_minor)
 286                         break;
 287                 minor += TAPE_MINORS_PER_DEV;
 288         }
 289         if (minor >= 256) {
 290                 write_unlock(&tape_device_lock);
 291                 return -ENODEV;
 292         }
 293         device->first_minor = minor;
 294         list_add_tail(&device->node, &tmp->node);
 295         write_unlock(&tape_device_lock);
 296         return 0;
 297 }
 298
 299 /* remove device from the list */
 300 static void
 301 tape_remove_minor(struct tape_device *device)
 302 {
 303         write_lock(&tape_device_lock);
 304         list_del_init(&device->node);
 305         device->first_minor = -1;
 306         write_unlock(&tape_device_lock);
 307 }
 308
 309 /*
 310  * Set a device online.
 311  *
 312  * This function is called by the common I/O layer to move a device from the
 313  * detected but offline into the online state.
 314  * If we return an error (RC < 0) the device remains in the offline state. This
 315  * can happen if the device is assigned somewhere else, for example.
 316  */
 317 int
 318 tape_generic_online(struct tape_device *device,
 319                    struct tape_discipline *discipline)
 320 {
 321         int rc;
 322
 323         DBF_LH(6, "tape_enable_device(%p, %p)\n", device, discipline);
 324
 325         if (device->tape_state != TS_INIT) {
 326                 DBF_LH(3, "Tapestate not INIT (%d)\n", device->tape_state);
 327                 return -EINVAL;
 328         }
 329
 330         init_timer(&device->lb_timeout);
 331         device->lb_timeout.function = tape_long_busy_timeout;
 332
 333         /* Let the discipline have a go at the device. */
 334         device->discipline = discipline;
 335         if (!try_module_get(discipline->owner)) {
 336                 PRINT_ERR("Cannot get module. Module gone.\n");
 337                 return -EINVAL;
 338         }
 339
 340         rc = discipline->setup_device(device);
 341         if (rc)
 342                 goto out;
 343         rc = tape_assign_minor(device);
 344         if (rc)
 345                 goto out_discipline;
 346
 347         rc = tapechar_setup_device(device);
 348         if (rc)
 349                 goto out_minor;
 350         rc = tapeblock_setup_device(device);
 351         if (rc)
 352                 goto out_char;
 353
 354         tape_state_set(device, TS_UNUSED);
 355
 356         DBF_LH(3, "(%08x): Drive set online\n", device->cdev_id);
 357
 358         return 0;
 359
 360 out_char:
 361         tapechar_cleanup_device(device);
 362 out_discipline:
 363         device->discipline->cleanup_device(device);
 364         device->discipline = NULL;
 365 out_minor:
 366         tape_remove_minor(device);
 367 out:
 368         module_put(discipline->owner);
 369         return rc;
 370 }
 371
 372 static void
 373 tape_cleanup_device(struct tape_device *device)
 374 {
 375         tapeblock_cleanup_device(device);
 376         tapechar_cleanup_device(device);
 377         device->discipline->cleanup_device(device);
 378         module_put(device->discipline->owner);
 379         tape_remove_minor(device);
 380         tape_med_state_set(device, MS_UNKNOWN);
 381 }
 382
 383 /*
 384  * Set device offline.
 385  *
 386  * Called by the common I/O layer if the drive should set offline on user
 387  * request. We may prevent this by returning an error.
 388  * Manual offline is only allowed while the drive is not in use.
 389  */
 390 int
 391 tape_generic_offline(struct tape_device *device)
 392 {
 393         if (!device) {
 394                 PRINT_ERR("tape_generic_offline: no such device\n");
 395                 return -ENODEV;
 396         }
 397
 398         DBF_LH(3, "(%08x): tape_generic_offline(%p)\n",
 399                 device->cdev_id, device);
 400
 401         spin_lock_irq(get_ccwdev_lock(device->cdev));
 402         switch (device->tape_state) {
 403                 case TS_INIT:
 404                 case TS_NOT_OPER:
 405                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 406                         break;
 407                 case TS_UNUSED:
 408                         tape_state_set(device, TS_INIT);
 409                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 410                         tape_cleanup_device(device);
 411                         break;
 412                 default:
 413                         DBF_EVENT(3, "(%08x): Set offline failed "
 414                                 "- drive in use.\n",
 415                                 device->cdev_id);
 416                         PRINT_WARN("(%s): Set offline failed "
 417                                 "- drive in use.\n",
 418                                 device->cdev->dev.bus_id);
 419                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 420                         return -EBUSY;
 421         }
 422
 423         DBF_LH(3, "(%08x): Drive set offline.\n", device->cdev_id);
 424         return 0;
 425 }
 426
 427 /*
 428  * Allocate memory for a new device structure.
 429  */
 430 static struct tape_device *
 431 tape_alloc_device(void)
 432 {
 433         struct tape_device *device;
 434
 435         device = kzalloc(sizeof(struct tape_device), GFP_KERNEL);
 436         if (device == NULL) {
 437                 DBF_EXCEPTION(2, "ti:no mem\n");
 438                 PRINT_INFO ("can't allocate memory for "
 439                             "tape info structure\n");
 440                 return ERR_PTR(-ENOMEM);
 441         }
 442         device->modeset_byte = kmalloc(1, GFP_KERNEL | GFP_DMA);
 443         if (device->modeset_byte == NULL) {
 444                 DBF_EXCEPTION(2, "ti:no mem\n");
 445                 PRINT_INFO("can't allocate memory for modeset byte\n");
 446                 kfree(device);
 447                 return ERR_PTR(-ENOMEM);
 448         }
 449         INIT_LIST_HEAD(&device->req_queue);
 450         INIT_LIST_HEAD(&device->node);
 451         init_waitqueue_head(&device->state_change_wq);
 452         init_waitqueue_head(&device->wait_queue);
 453         device->tape_state = TS_INIT;
 454         device->medium_state = MS_UNKNOWN;
 455         *device->modeset_byte = 0;
 456         device->first_minor = -1;
 457         atomic_set(&device->ref_count, 1);
 458         INIT_DELAYED_WORK(&device->tape_dnr, tape_delayed_next_request);
 459
 460         return device;
 461 }
 462
 463 /*
 464  * Get a reference to an existing device structure. This will automatically
 465  * increment the reference count.
 466  */
 467 struct tape_device *
 468 tape_get_device_reference(struct tape_device *device)
 469 {
 470         DBF_EVENT(4, "tape_get_device_reference(%p) = %i\n", device,
 471                 atomic_inc_return(&device->ref_count));
 472
 473         return device;
 474 }
 475
 476 /*
 477  * Decrease the reference counter of a devices structure. If the
 478  * reference counter reaches zero free the device structure.
 479  * The function returns a NULL pointer to be used by the caller
 480  * for clearing reference pointers.
 481  */
 482 struct tape_device *
 483 tape_put_device(struct tape_device *device)
 484 {
 485         int remain;
 486
 487         remain = atomic_dec_return(&device->ref_count);
 488         if (remain > 0) {
 489                 DBF_EVENT(4, "tape_put_device(%p) -> %i\n", device, remain);
 490         } else {
 491                 if (remain < 0) {
 492                         DBF_EVENT(4, "put device without reference\n");
 493                         PRINT_ERR("put device without reference\n");
 494                 } else {
 495                         DBF_EVENT(4, "tape_free_device(%p)\n", device);
 496                         kfree(device->modeset_byte);
 497                         kfree(device);
 498                 }
 499         }
 500
 501         return NULL;
 502 }
 503
 504 /*
 505  * Find tape device by a device index.
 506  */
 507 struct tape_device *
 508 tape_get_device(int devindex)
 509 {
 510         struct tape_device *device, *tmp;
 511
 512         device = ERR_PTR(-ENODEV);
 513         read_lock(&tape_device_lock);
 514         list_for_each_entry(tmp, &tape_device_list, node) {
 515                 if (tmp->first_minor / TAPE_MINORS_PER_DEV == devindex) {
 516                         device = tape_get_device_reference(tmp);
 517                         break;
 518                 }
 519         }
 520         read_unlock(&tape_device_lock);
 521         return device;
 522 }
 523
 524 /*
 525  * Driverfs tape probe function.
 526  */
 527 int
 528 tape_generic_probe(struct ccw_device *cdev)
 529 {
 530         struct tape_device *device;
 531         int ret;
 532         struct ccw_dev_id dev_id;
 533
 534         device = tape_alloc_device();
 535         if (IS_ERR(device))
 536                 return -ENODEV;
 537         ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP);
 538         ret = sysfs_create_group(&cdev->dev.kobj, &tape_attr_group);
 539         if (ret) {
 540                 tape_put_device(device);
 541                 PRINT_ERR("probe failed for tape device %s\n", cdev->dev.bus_id);
 542                 return ret;
 543         }
 544         cdev->dev.driver_data = device;
 545         cdev->handler = __tape_do_irq;
 546         device->cdev = cdev;
 547         ccw_device_get_id(cdev, &dev_id);
 548         device->cdev_id = devid_to_int(&dev_id);
 549         PRINT_INFO("tape device %s found\n", cdev->dev.bus_id);
 550         return ret;
 551 }
 552
 553 static void
 554 __tape_discard_requests(struct tape_device *device)
 555 {
 556         struct tape_request *   request;
 557         struct list_head *      l, *n;
 558
 559         list_for_each_safe(l, n, &device->req_queue) {
 560                 request = list_entry(l, struct tape_request, list);
 561                 if (request->status == TAPE_REQUEST_IN_IO)
 562                         request->status = TAPE_REQUEST_DONE;
 563                 list_del(&request->list);
 564
 565                 /* Decrease ref_count for removed request. */
 566                 request->device = tape_put_device(device);
 567                 request->rc = -EIO;
 568                 if (request->callback != NULL)
 569                         request->callback(request, request->callback_data);
 570         }
 571 }
 572
 573 /*
 574  * Driverfs tape remove function.
 575  *
 576  * This function is called whenever the common I/O layer detects the device
 577  * gone. This can happen at any time and we cannot refuse.
 578  */
 579 void
 580 tape_generic_remove(struct ccw_device *cdev)
 581 {
 582         struct tape_device *    device;
 583
 584         device = cdev->dev.driver_data;
 585         if (!device) {
 586                 PRINT_ERR("No device pointer in tape_generic_remove!\n");
 587                 return;
 588         }
 589         DBF_LH(3, "(%08x): tape_generic_remove(%p)\n", device->cdev_id, cdev);
 590
 591         spin_lock_irq(get_ccwdev_lock(device->cdev));
 592         switch (device->tape_state) {
 593                 case TS_INIT:
 594                         tape_state_set(device, TS_NOT_OPER);
 595                 case TS_NOT_OPER:
 596                         /*
 597                          * Nothing to do.
 598                          */
 599                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 600                         break;
 601                 case TS_UNUSED:
 602                         /*
 603                          * Need only to release the device.
 604                          */
 605                         tape_state_set(device, TS_NOT_OPER);
 606                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 607                         tape_cleanup_device(device);
 608                         break;
 609                 default:
 610                         /*
 611                          * There may be requests on the queue. We will not get
 612                          * an interrupt for a request that was running. So we
 613                          * just post them all as I/O errors.
 614                          */
 615                         DBF_EVENT(3, "(%08x): Drive in use vanished!\n",
 616                                 device->cdev_id);
 617                         PRINT_WARN("(%s): Drive in use vanished - "
 618                                 "expect trouble!\n",
 619                                 device->cdev->dev.bus_id);
 620                         PRINT_WARN("State was %i\n", device->tape_state);
 621                         tape_state_set(device, TS_NOT_OPER);
 622                         __tape_discard_requests(device);
 623                         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 624                         tape_cleanup_device(device);
 625         }
 626
 627         if (cdev->dev.driver_data != NULL) {
 628                 sysfs_remove_group(&cdev->dev.kobj, &tape_attr_group);
 629                 cdev->dev.driver_data = tape_put_device(cdev->dev.driver_data);
 630         }
 631 }
 632
 633 /*
 634  * Allocate a new tape ccw request
 635  */
 636 struct tape_request *
 637 tape_alloc_request(int cplength, int datasize)
 638 {
 639         struct tape_request *request;
 640
 641         if (datasize > PAGE_SIZE || (cplength*sizeof(struct ccw1)) > PAGE_SIZE)
 642                 BUG();
 643
 644         DBF_LH(6, "tape_alloc_request(%d, %d)\n", cplength, datasize);
 645
 646         request = kzalloc(sizeof(struct tape_request), GFP_KERNEL);
 647         if (request == NULL) {
 648                 DBF_EXCEPTION(1, "cqra nomem\n");
 649                 return ERR_PTR(-ENOMEM);
 650         }
 651         /* allocate channel program */
 652         if (cplength > 0) {
 653                 request->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
 654                                           GFP_ATOMIC | GFP_DMA);
 655                 if (request->cpaddr == NULL) {
 656                         DBF_EXCEPTION(1, "cqra nomem\n");
 657                         kfree(request);
 658                         return ERR_PTR(-ENOMEM);
 659                 }
 660         }
 661         /* alloc small kernel buffer */
 662         if (datasize > 0) {
 663                 request->cpdata = kzalloc(datasize, GFP_KERNEL | GFP_DMA);
 664                 if (request->cpdata == NULL) {
 665                         DBF_EXCEPTION(1, "cqra nomem\n");
 666                         kfree(request->cpaddr);
 667                         kfree(request);
 668                         return ERR_PTR(-ENOMEM);
 669                 }
 670         }
 671         DBF_LH(6, "New request %p(%p/%p)\n", request, request->cpaddr,
 672                 request->cpdata);
 673
 674         return request;
 675 }
 676
 677 /*
 678  * Free tape ccw request
 679  */
 680 void
 681 tape_free_request (struct tape_request * request)
 682 {
 683         DBF_LH(6, "Free request %p\n", request);
 684
 685         if (request->device != NULL) {
 686                 request->device = tape_put_device(request->device);
 687         }
 688         kfree(request->cpdata);
 689         kfree(request->cpaddr);
 690         kfree(request);
 691 }
 692
 693 static int
 694 __tape_start_io(struct tape_device *device, struct tape_request *request)
 695 {
 696         int rc;
 697
 698 #ifdef CONFIG_S390_TAPE_BLOCK
 699         if (request->op == TO_BLOCK)
 700                 device->discipline->check_locate(device, request);
 701 #endif
 702         rc = ccw_device_start(
 703                 device->cdev,
 704                 request->cpaddr,
 705                 (unsigned long) request,
 706                 0x00,
 707                 request->options
 708         );
 709         if (rc == 0) {
 710                 request->status = TAPE_REQUEST_IN_IO;
 711         } else if (rc == -EBUSY) {
 712                 /* The common I/O subsystem is currently busy. Retry later. */
 713                 request->status = TAPE_REQUEST_QUEUED;
 714                 schedule_delayed_work(&device->tape_dnr, 0);
 715                 rc = 0;
 716         } else {
 717                 /* Start failed. Remove request and indicate failure. */
 718                 DBF_EVENT(1, "tape: start request failed with RC = %i\n", rc);
 719         }
 720         return rc;
 721 }
 722
 723 static void
 724 __tape_start_next_request(struct tape_device *device)
 725 {
 726         struct list_head *l, *n;
 727         struct tape_request *request;
 728         int rc;
 729
 730         DBF_LH(6, "__tape_start_next_request(%p)\n", device);
 731         /*
 732          * Try to start each request on request queue until one is
 733          * started successful.
 734          */
 735         list_for_each_safe(l, n, &device->req_queue) {
 736                 request = list_entry(l, struct tape_request, list);
 737
 738                 /*
 739                  * Avoid race condition if bottom-half was triggered more than
 740                  * once.
 741                  */
 742                 if (request->status == TAPE_REQUEST_IN_IO)
 743                         return;
 744                 /*
 745                  * Request has already been stopped. We have to wait until
 746                  * the request is removed from the queue in the interrupt
 747                  * handling.
 748                  */
 749                 if (request->status == TAPE_REQUEST_DONE)
 750                         return;
 751
 752                 /*
 753                  * We wanted to cancel the request but the common I/O layer
 754                  * was busy at that time. This can only happen if this
 755                  * function is called by delayed_next_request.
 756                  * Otherwise we start the next request on the queue.
 757                  */
 758                 if (request->status == TAPE_REQUEST_CANCEL) {
 759                         rc = __tape_cancel_io(device, request);
 760                 } else {
 761                         rc = __tape_start_io(device, request);
 762                 }
 763                 if (rc == 0)
 764                         return;
 765
 766                 /* Set ending status. */
 767                 request->rc = rc;
 768                 request->status = TAPE_REQUEST_DONE;
 769
 770                 /* Remove from request queue. */
 771                 list_del(&request->list);
 772
 773                 /* Do callback. */
 774                 if (request->callback != NULL)
 775                         request->callback(request, request->callback_data);
 776         }
 777 }
 778
 779 static void
 780 tape_delayed_next_request(struct work_struct *work)
 781 {
 782         struct tape_device *device =
 783                 container_of(work, struct tape_device, tape_dnr.work);
 784
 785         DBF_LH(6, "tape_delayed_next_request(%p)\n", device);
 786         spin_lock_irq(get_ccwdev_lock(device->cdev));
 787         __tape_start_next_request(device);
 788         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 789 }
 790
 791 static void tape_long_busy_timeout(unsigned long data)
 792 {
 793         struct tape_request *request;
 794         struct tape_device *device;
 795
 796         device = (struct tape_device *) data;
 797         spin_lock_irq(get_ccwdev_lock(device->cdev));
 798         request = list_entry(device->req_queue.next, struct tape_request, list);
 799         if (request->status != TAPE_REQUEST_LONG_BUSY)
 800                 BUG();
 801         DBF_LH(6, "%08x: Long busy timeout.\n", device->cdev_id);
 802         __tape_start_next_request(device);
 803         device->lb_timeout.data = (unsigned long) tape_put_device(device);
 804         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 805 }
 806
 807 static void
 808 __tape_end_request(
 809         struct tape_device *    device,
 810         struct tape_request *   request,
 811         int                     rc)
 812 {
 813         DBF_LH(6, "__tape_end_request(%p, %p, %i)\n", device, request, rc);
 814         if (request) {
 815                 request->rc = rc;
 816                 request->status = TAPE_REQUEST_DONE;
 817
 818                 /* Remove from request queue. */
 819                 list_del(&request->list);
 820
 821                 /* Do callback. */
 822                 if (request->callback != NULL)
 823                         request->callback(request, request->callback_data);
 824         }
 825
 826         /* Start next request. */
 827         if (!list_empty(&device->req_queue))
 828                 __tape_start_next_request(device);
 829 }
 830
 831 /*
 832  * Write sense data to console/dbf
 833  */
 834 void
 835 tape_dump_sense(struct tape_device* device, struct tape_request *request,
 836                 struct irb *irb)
 837 {
 838         unsigned int *sptr;
 839
 840         PRINT_INFO("-------------------------------------------------\n");
 841         PRINT_INFO("DSTAT : %02x  CSTAT: %02x   CPA: %04x\n",
 842                    irb->scsw.dstat, irb->scsw.cstat, irb->scsw.cpa);
 843         PRINT_INFO("DEVICE: %s\n", device->cdev->dev.bus_id);
 844         if (request != NULL)
 845                 PRINT_INFO("OP    : %s\n", tape_op_verbose[request->op]);
 846
 847         sptr = (unsigned int *) irb->ecw;
 848         PRINT_INFO("Sense data: %08X %08X %08X %08X \n",
 849                    sptr[0], sptr[1], sptr[2], sptr[3]);
 850         PRINT_INFO("Sense data: %08X %08X %08X %08X \n",
 851                    sptr[4], sptr[5], sptr[6], sptr[7]);
 852         PRINT_INFO("--------------------------------------------------\n");
 853 }
 854
 855 /*
 856  * Write sense data to dbf
 857  */
 858 void
 859 tape_dump_sense_dbf(struct tape_device *device, struct tape_request *request,
 860                     struct irb *irb)
 861 {
 862         unsigned int *sptr;
 863         const char* op;
 864
 865         if (request != NULL)
 866                 op = tape_op_verbose[request->op];
 867         else
 868                 op = "---";
 869         DBF_EVENT(3, "DSTAT : %02x   CSTAT: %02x\n",
 870                   irb->scsw.dstat,irb->scsw.cstat);
 871         DBF_EVENT(3, "DEVICE: %08x OP\t: %s\n", device->cdev_id, op);
 872         sptr = (unsigned int *) irb->ecw;
 873         DBF_EVENT(3, "%08x %08x\n", sptr[0], sptr[1]);
 874         DBF_EVENT(3, "%08x %08x\n", sptr[2], sptr[3]);
 875         DBF_EVENT(3, "%08x %08x\n", sptr[4], sptr[5]);
 876         DBF_EVENT(3, "%08x %08x\n", sptr[6], sptr[7]);
 877 }
 878
 879 /*
 880  * I/O helper function. Adds the request to the request queue
 881  * and starts it if the tape is idle. Has to be called with
 882  * the device lock held.
 883  */
 884 static int
 885 __tape_start_request(struct tape_device *device, struct tape_request *request)
 886 {
 887         int rc;
 888
 889         switch (request->op) {
 890                 case TO_MSEN:
 891                 case TO_ASSIGN:
 892                 case TO_UNASSIGN:
 893                 case TO_READ_ATTMSG:
 894                 case TO_RDC:
 895                         if (device->tape_state == TS_INIT)
 896                                 break;
 897                         if (device->tape_state == TS_UNUSED)
 898                                 break;
 899                 default:
 900                         if (device->tape_state == TS_BLKUSE)
 901                                 break;
 902                         if (device->tape_state != TS_IN_USE)
 903                                 return -ENODEV;
 904         }
 905
 906         /* Increase use count of device for the added request. */
 907         request->device = tape_get_device_reference(device);
 908
 909         if (list_empty(&device->req_queue)) {
 910                 /* No other requests are on the queue. Start this one. */
 911                 rc = __tape_start_io(device, request);
 912                 if (rc)
 913                         return rc;
 914
 915                 DBF_LH(5, "Request %p added for execution.\n", request);
 916                 list_add(&request->list, &device->req_queue);
 917         } else {
 918                 DBF_LH(5, "Request %p add to queue.\n", request);
 919                 request->status = TAPE_REQUEST_QUEUED;
 920                 list_add_tail(&request->list, &device->req_queue);
 921         }
 922         return 0;
 923 }
 924
 925 /*
 926  * Add the request to the request queue, try to start it if the
 927  * tape is idle. Return without waiting for end of i/o.
 928  */
 929 int
 930 tape_do_io_async(struct tape_device *device, struct tape_request *request)
 931 {
 932         int rc;
 933
 934         DBF_LH(6, "tape_do_io_async(%p, %p)\n", device, request);
 935
 936         spin_lock_irq(get_ccwdev_lock(device->cdev));
 937         /* Add request to request queue and try to start it. */
 938         rc = __tape_start_request(device, request);
 939         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 940         return rc;
 941 }
 942
 943 /*
 944  * tape_do_io/__tape_wake_up
 945  * Add the request to the request queue, try to start it if the
 946  * tape is idle and wait uninterruptible for its completion.
 947  */
 948 static void
 949 __tape_wake_up(struct tape_request *request, void *data)
 950 {
 951         request->callback = NULL;
 952         wake_up((wait_queue_head_t *) data);
 953 }
 954
 955 int
 956 tape_do_io(struct tape_device *device, struct tape_request *request)
 957 {
 958         int rc;
 959
 960         spin_lock_irq(get_ccwdev_lock(device->cdev));
 961         /* Setup callback */
 962         request->callback = __tape_wake_up;
 963         request->callback_data = &device->wait_queue;
 964         /* Add request to request queue and try to start it. */
 965         rc = __tape_start_request(device, request);
 966         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 967         if (rc)
 968                 return rc;
 969         /* Request added to the queue. Wait for its completion. */
 970         wait_event(device->wait_queue, (request->callback == NULL));
 971         /* Get rc from request */
 972         return request->rc;
 973 }
 974
 975 /*
 976  * tape_do_io_interruptible/__tape_wake_up_interruptible
 977  * Add the request to the request queue, try to start it if the
 978  * tape is idle and wait uninterruptible for its completion.
 979  */
 980 static void
 981 __tape_wake_up_interruptible(struct tape_request *request, void *data)
 982 {
 983         request->callback = NULL;
 984         wake_up_interruptible((wait_queue_head_t *) data);
 985 }
 986
 987 int
 988 tape_do_io_interruptible(struct tape_device *device,
 989                          struct tape_request *request)
 990 {
 991         int rc;
 992
 993         spin_lock_irq(get_ccwdev_lock(device->cdev));
 994         /* Setup callback */
 995         request->callback = __tape_wake_up_interruptible;
 996         request->callback_data = &device->wait_queue;
 997         rc = __tape_start_request(device, request);
 998         spin_unlock_irq(get_ccwdev_lock(device->cdev));
 999         if (rc)
1000                 return rc;
1001         /* Request added to the queue. Wait for its completion. */
1002         rc = wait_event_interruptible(device->wait_queue,
1003                                       (request->callback == NULL));
1004         if (rc != -ERESTARTSYS)
1005                 /* Request finished normally. */
1006                 return request->rc;
1007
1008         /* Interrupted by a signal. We have to stop the current request. */
1009         spin_lock_irq(get_ccwdev_lock(device->cdev));
1010         rc = __tape_cancel_io(device, request);
1011         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1012         if (rc == 0) {
1013                 /* Wait for the interrupt that acknowledges the halt. */
1014                 do {
1015                         rc = wait_event_interruptible(
1016                                 device->wait_queue,
1017                                 (request->callback == NULL)
1018                         );
1019                 } while (rc == -ERESTARTSYS);
1020
1021                 DBF_EVENT(3, "IO stopped on %08x\n", device->cdev_id);
1022                 rc = -ERESTARTSYS;
1023         }
1024         return rc;
1025 }
1026
1027 /*
1028  * Stop running ccw.
1029  */
1030 int
1031 tape_cancel_io(struct tape_device *device, struct tape_request *request)
1032 {
1033         int rc;
1034
1035         spin_lock_irq(get_ccwdev_lock(device->cdev));
1036         rc = __tape_cancel_io(device, request);
1037         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1038         return rc;
1039 }
1040
1041 /*
1042  * Tape interrupt routine, called from the ccw_device layer
1043  */
1044 static void
1045 __tape_do_irq (struct ccw_device *cdev, unsigned long intparm, struct irb *irb)
1046 {
1047         struct tape_device *device;
1048         struct tape_request *request;
1049         int rc;
1050
1051         device = (struct tape_device *) cdev->dev.driver_data;
1052         if (device == NULL) {
1053                 PRINT_ERR("could not get device structure for %s "
1054                           "in interrupt\n", cdev->dev.bus_id);
1055                 return;
1056         }
1057         request = (struct tape_request *) intparm;
1058
1059         DBF_LH(6, "__tape_do_irq(device=%p, request=%p)\n", device, request);
1060
1061         /* On special conditions irb is an error pointer */
1062         if (IS_ERR(irb)) {
1063                 /* FIXME: What to do with the request? */
1064                 switch (PTR_ERR(irb)) {
1065                         case -ETIMEDOUT:
1066                                 PRINT_WARN("(%s): Request timed out\n",
1067                                         cdev->dev.bus_id);
1068                         case -EIO:
1069                                 __tape_end_request(device, request, -EIO);
1070                                 break;
1071                         default:
1072                                 PRINT_ERR("(%s): Unexpected i/o error %li\n",
1073                                         cdev->dev.bus_id,
1074                                         PTR_ERR(irb));
1075                 }
1076                 return;
1077         }
1078
1079         /*
1080          * If the condition code is not zero and the start function bit is
1081          * still set, this is an deferred error and the last start I/O did
1082          * not succeed. At this point the condition that caused the deferred
1083          * error might still apply. So we just schedule the request to be
1084          * started later.
1085          */
1086         if (irb->scsw.cc != 0 && (irb->scsw.fctl & SCSW_FCTL_START_FUNC) &&
1087             (request->status == TAPE_REQUEST_IN_IO)) {
1088                 DBF_EVENT(3,"(%08x): deferred cc=%i, fctl=%i. restarting\n",
1089                         device->cdev_id, irb->scsw.cc, irb->scsw.fctl);
1090                 request->status = TAPE_REQUEST_QUEUED;
1091                 schedule_delayed_work(&device->tape_dnr, HZ);
1092                 return;
1093         }
1094
1095         /* May be an unsolicited irq */
1096         if(request != NULL)
1097                 request->rescnt = irb->scsw.count;
1098         else if ((irb->scsw.dstat == 0x85 || irb->scsw.dstat == 0x80) &&
1099                  !list_empty(&device->req_queue)) {
1100                 /* Not Ready to Ready after long busy ? */
1101                 struct tape_request *req;
1102                 req = list_entry(device->req_queue.next,
1103                                  struct tape_request, list);
1104                 if (req->status == TAPE_REQUEST_LONG_BUSY) {
1105                         DBF_EVENT(3, "(%08x): del timer\n", device->cdev_id);
1106                         if (del_timer(&device->lb_timeout)) {
1107                                 device->lb_timeout.data = (unsigned long)
1108                                         tape_put_device(device);
1109                                 __tape_start_next_request(device);
1110                         }
1111                         return;
1112                 }
1113         }
1114         if (irb->scsw.dstat != 0x0c) {
1115                 /* Set the 'ONLINE' flag depending on sense byte 1 */
1116                 if(*(((__u8 *) irb->ecw) + 1) & SENSE_DRIVE_ONLINE)
1117                         device->tape_generic_status |= GMT_ONLINE(~0);
1118                 else
1119                         device->tape_generic_status &= ~GMT_ONLINE(~0);
1120
1121                 /*
1122                  * Any request that does not come back with channel end
1123                  * and device end is unusual. Log the sense data.
1124                  */
1125                 DBF_EVENT(3,"-- Tape Interrupthandler --\n");
1126                 tape_dump_sense_dbf(device, request, irb);
1127         } else {
1128                 /* Upon normal completion the device _is_ online */
1129                 device->tape_generic_status |= GMT_ONLINE(~0);
1130         }
1131         if (device->tape_state == TS_NOT_OPER) {
1132                 DBF_EVENT(6, "tape:device is not operational\n");
1133                 return;
1134         }
1135
1136         /*
1137          * Request that were canceled still come back with an interrupt.
1138          * To detect these request the state will be set to TAPE_REQUEST_DONE.
1139          */
1140         if(request != NULL && request->status == TAPE_REQUEST_DONE) {
1141                 __tape_end_request(device, request, -EIO);
1142                 return;
1143         }
1144
1145         rc = device->discipline->irq(device, request, irb);
1146         /*
1147          * rc < 0 : request finished unsuccessfully.
1148          * rc == TAPE_IO_SUCCESS: request finished successfully.
1149          * rc == TAPE_IO_PENDING: request is still running. Ignore rc.
1150          * rc == TAPE_IO_RETRY: request finished but needs another go.
1151          * rc == TAPE_IO_STOP: request needs to get terminated.
1152          */
1153         switch (rc) {
1154                 case TAPE_IO_SUCCESS:
1155                         /* Upon normal completion the device _is_ online */
1156                         device->tape_generic_status |= GMT_ONLINE(~0);
1157                         __tape_end_request(device, request, rc);
1158                         break;
1159                 case TAPE_IO_PENDING:
1160                         break;
1161                 case TAPE_IO_LONG_BUSY:
1162                         device->lb_timeout.data =
1163                                 (unsigned long)tape_get_device_reference(device);
1164                         device->lb_timeout.expires = jiffies +
1165                                 LONG_BUSY_TIMEOUT * HZ;
1166                         DBF_EVENT(3, "(%08x): add timer\n", device->cdev_id);
1167                         add_timer(&device->lb_timeout);
1168                         request->status = TAPE_REQUEST_LONG_BUSY;
1169                         break;
1170                 case TAPE_IO_RETRY:
1171                         rc = __tape_start_io(device, request);
1172                         if (rc)
1173                                 __tape_end_request(device, request, rc);
1174                         break;
1175                 case TAPE_IO_STOP:
1176                         rc = __tape_cancel_io(device, request);
1177                         if (rc)
1178                                 __tape_end_request(device, request, rc);
1179                         break;
1180                 default:
1181                         if (rc > 0) {
1182                                 DBF_EVENT(6, "xunknownrc\n");
1183                                 PRINT_ERR("Invalid return code from discipline "
1184                                         "interrupt function.\n");
1185                                 __tape_end_request(device, request, -EIO);
1186                         } else {
1187                                 __tape_end_request(device, request, rc);
1188                         }
1189                         break;
1190         }
1191 }
1192
1193 /*
1194  * Tape device open function used by tape_char & tape_block frontends.
1195  */
1196 int
1197 tape_open(struct tape_device *device)
1198 {
1199         int rc;
1200
1201         spin_lock(get_ccwdev_lock(device->cdev));
1202         if (device->tape_state == TS_NOT_OPER) {
1203                 DBF_EVENT(6, "TAPE:nodev\n");
1204                 rc = -ENODEV;
1205         } else if (device->tape_state == TS_IN_USE) {
1206                 DBF_EVENT(6, "TAPE:dbusy\n");
1207                 rc = -EBUSY;
1208         } else if (device->tape_state == TS_BLKUSE) {
1209                 DBF_EVENT(6, "TAPE:dbusy\n");
1210                 rc = -EBUSY;
1211         } else if (device->discipline != NULL &&
1212                    !try_module_get(device->discipline->owner)) {
1213                 DBF_EVENT(6, "TAPE:nodisc\n");
1214                 rc = -ENODEV;
1215         } else {
1216                 tape_state_set(device, TS_IN_USE);
1217                 rc = 0;
1218         }
1219         spin_unlock(get_ccwdev_lock(device->cdev));
1220         return rc;
1221 }
1222
1223 /*
1224  * Tape device release function used by tape_char & tape_block frontends.
1225  */
1226 int
1227 tape_release(struct tape_device *device)
1228 {
1229         spin_lock(get_ccwdev_lock(device->cdev));
1230         if (device->tape_state == TS_IN_USE)
1231                 tape_state_set(device, TS_UNUSED);
1232         module_put(device->discipline->owner);
1233         spin_unlock(get_ccwdev_lock(device->cdev));
1234         return 0;
1235 }
1236
1237 /*
1238  * Execute a magnetic tape command a number of times.
1239  */
1240 int
1241 tape_mtop(struct tape_device *device, int mt_op, int mt_count)
1242 {
1243         tape_mtop_fn fn;
1244         int rc;
1245
1246         DBF_EVENT(6, "TAPE:mtio\n");
1247         DBF_EVENT(6, "TAPE:ioop: %x\n", mt_op);
1248         DBF_EVENT(6, "TAPE:arg:  %x\n", mt_count);
1249
1250         if (mt_op < 0 || mt_op >= TAPE_NR_MTOPS)
1251                 return -EINVAL;
1252         fn = device->discipline->mtop_array[mt_op];
1253         if (fn == NULL)
1254                 return -EINVAL;
1255
1256         /* We assume that the backends can handle count up to 500. */
1257         if (mt_op == MTBSR  || mt_op == MTFSR  || mt_op == MTFSF  ||
1258             mt_op == MTBSF  || mt_op == MTFSFM || mt_op == MTBSFM) {
1259                 rc = 0;
1260                 for (; mt_count > 500; mt_count -= 500)
1261                         if ((rc = fn(device, 500)) != 0)
1262                                 break;
1263                 if (rc == 0)
1264                         rc = fn(device, mt_count);
1265         } else
1266                 rc = fn(device, mt_count);
1267         return rc;
1268
1269 }
1270
1271 /*
1272  * Tape init function.
1273  */
1274 static int
1275 tape_init (void)
1276 {
1277         TAPE_DBF_AREA = debug_register ( "tape", 2, 2, 4*sizeof(long));
1278         debug_register_view(TAPE_DBF_AREA, &debug_sprintf_view);
1279 #ifdef DBF_LIKE_HELL
1280         debug_set_level(TAPE_DBF_AREA, 6);
1281 #endif
1282         DBF_EVENT(3, "tape init\n");
1283         tape_proc_init();
1284         tapechar_init ();
1285         tapeblock_init ();
1286         return 0;
1287 }
1288
1289 /*
1290  * Tape exit function.
1291  */
1292 static void
1293 tape_exit(void)
1294 {
1295         DBF_EVENT(6, "tape exit\n");
1296
1297         /* Get rid of the frontends */
1298         tapechar_exit();
1299         tapeblock_exit();
1300         tape_proc_cleanup();
1301         debug_unregister (TAPE_DBF_AREA);
1302 }
1303
1304 MODULE_AUTHOR("(C) 2001 IBM Deutschland Entwicklung GmbH by Carsten Otte and "
1305               "Michael Holzheu (cotte@de.ibm.com,holzheu@de.ibm.com)");
1306 MODULE_DESCRIPTION("Linux on zSeries channel attached tape device driver");
1307 MODULE_LICENSE("GPL");
1308
1309 module_init(tape_init);
1310 module_exit(tape_exit);
1311
1312 EXPORT_SYMBOL(tape_generic_remove);
1313 EXPORT_SYMBOL(tape_generic_probe);
1314 EXPORT_SYMBOL(tape_generic_online);
1315 EXPORT_SYMBOL(tape_generic_offline);
1316 EXPORT_SYMBOL(tape_put_device);
1317 EXPORT_SYMBOL(tape_get_device_reference);
1318 EXPORT_SYMBOL(tape_state_verbose);
1319 EXPORT_SYMBOL(tape_op_verbose);
1320 EXPORT_SYMBOL(tape_state_set);
1321 EXPORT_SYMBOL(tape_med_state_set);
1322 EXPORT_SYMBOL(tape_alloc_request);
1323 EXPORT_SYMBOL(tape_free_request);
1324 EXPORT_SYMBOL(tape_dump_sense);
1325 EXPORT_SYMBOL(tape_dump_sense_dbf);
1326 EXPORT_SYMBOL(tape_do_io);
1327 EXPORT_SYMBOL(tape_do_io_async);
1328 EXPORT_SYMBOL(tape_do_io_interruptible);
1329 EXPORT_SYMBOL(tape_cancel_io);
1330 EXPORT_SYMBOL(tape_mtop);