kernel/drivers/s390/char/tape_34xx.c

   1 /*
   2  *    tape device discipline for 3480/3490 tapes.
   3  *
   4  *    Copyright IBM Corp. 2001, 2009
   5  *    Author(s): Carsten Otte <cotte@de.ibm.com>
   6  *               Tuan Ngo-Anh <ngoanh@de.ibm.com>
   7  *               Martin Schwidefsky <schwidefsky@de.ibm.com>
   8  */
   9
  10 #define KMSG_COMPONENT "tape_34xx"
  11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  12
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/bio.h>
  16 #include <linux/workqueue.h>
  17 #include <linux/slab.h>
  18
  19 #define TAPE_DBF_AREA   tape_34xx_dbf
  20
  21 #include "tape.h"
  22 #include "tape_std.h"
  23
  24 /*
  25  * Pointer to debug area.
  26  */
  27 debug_info_t *TAPE_DBF_AREA = NULL;
  28 EXPORT_SYMBOL(TAPE_DBF_AREA);
  29
  30 #define TAPE34XX_FMT_3480       0
  31 #define TAPE34XX_FMT_3480_2_XF  1
  32 #define TAPE34XX_FMT_3480_XF    2
  33
  34 struct tape_34xx_block_id {
  35         unsigned int    wrap            : 1;
  36         unsigned int    segment         : 7;
  37         unsigned int    format          : 2;
  38         unsigned int    block           : 22;
  39 };
  40
  41 /*
  42  * A list of block ID's is used to faster seek blocks.
  43  */
  44 struct tape_34xx_sbid {
  45         struct list_head                list;
  46         struct tape_34xx_block_id       bid;
  47 };
  48
  49 static void tape_34xx_delete_sbid_from(struct tape_device *, int);
  50
  51 /*
  52  * Medium sense for 34xx tapes. There is no 'real' medium sense call.
  53  * So we just do a normal sense.
  54  */
  55 static void __tape_34xx_medium_sense(struct tape_request *request)
  56 {
  57         struct tape_device *device = request->device;
  58         unsigned char *sense;
  59
  60         if (request->rc == 0) {
  61                 sense = request->cpdata;
  62
  63                 /*
  64                  * This isn't quite correct. But since INTERVENTION_REQUIRED
  65                  * means that the drive is 'neither ready nor on-line' it is
  66                  * only slightly inaccurate to say there is no tape loaded if
  67                  * the drive isn't online...
  68                  */
  69                 if (sense[0] & SENSE_INTERVENTION_REQUIRED)
  70                         tape_med_state_set(device, MS_UNLOADED);
  71                 else
  72                         tape_med_state_set(device, MS_LOADED);
  73
  74                 if (sense[1] & SENSE_WRITE_PROTECT)
  75                         device->tape_generic_status |= GMT_WR_PROT(~0);
  76                 else
  77                         device->tape_generic_status &= ~GMT_WR_PROT(~0);
  78         } else
  79                 DBF_EVENT(4, "tape_34xx: medium sense failed with rc=%d\n",
  80                         request->rc);
  81         tape_free_request(request);
  82 }
  83
  84 static int tape_34xx_medium_sense(struct tape_device *device)
  85 {
  86         struct tape_request *request;
  87         int rc;
  88
  89         request = tape_alloc_request(1, 32);
  90         if (IS_ERR(request)) {
  91                 DBF_EXCEPTION(6, "MSEN fail\n");
  92                 return PTR_ERR(request);
  93         }
  94
  95         request->op = TO_MSEN;
  96         tape_ccw_end(request->cpaddr, SENSE, 32, request->cpdata);
  97         rc = tape_do_io_interruptible(device, request);
  98         __tape_34xx_medium_sense(request);
  99         return rc;
 100 }
 101
 102 static void tape_34xx_medium_sense_async(struct tape_device *device)
 103 {
 104         struct tape_request *request;
 105
 106         request = tape_alloc_request(1, 32);
 107         if (IS_ERR(request)) {
 108                 DBF_EXCEPTION(6, "MSEN fail\n");
 109                 return;
 110         }
 111
 112         request->op = TO_MSEN;
 113         tape_ccw_end(request->cpaddr, SENSE, 32, request->cpdata);
 114         request->callback = (void *) __tape_34xx_medium_sense;
 115         request->callback_data = NULL;
 116         tape_do_io_async(device, request);
 117 }
 118
 119 struct tape_34xx_work {
 120         struct tape_device      *device;
 121         enum tape_op             op;
 122         struct work_struct       work;
 123 };
 124
 125 /*
 126  * These functions are currently used only to schedule a medium_sense for
 127  * later execution. This is because we get an interrupt whenever a medium
 128  * is inserted but cannot call tape_do_io* from an interrupt context.
 129  * Maybe that's useful for other actions we want to start from the
 130  * interrupt handler.
 131  * Note: the work handler is called by the system work queue. The tape
 132  * commands started by the handler need to be asynchrounous, otherwise
 133  * a deadlock can occur e.g. in case of a deferred cc=1 (see __tape_do_irq).
 134  */
 135 static void
 136 tape_34xx_work_handler(struct work_struct *work)
 137 {
 138         struct tape_34xx_work *p =
 139                 container_of(work, struct tape_34xx_work, work);
 140         struct tape_device *device = p->device;
 141
 142         switch(p->op) {
 143                 case TO_MSEN:
 144                         tape_34xx_medium_sense_async(device);
 145                         break;
 146                 default:
 147                         DBF_EVENT(3, "T34XX: internal error: unknown work\n");
 148         }
 149         tape_put_device(device);
 150         kfree(p);
 151 }
 152
 153 static int
 154 tape_34xx_schedule_work(struct tape_device *device, enum tape_op op)
 155 {
 156         struct tape_34xx_work *p;
 157
 158         if ((p = kzalloc(sizeof(*p), GFP_ATOMIC)) == NULL)
 159                 return -ENOMEM;
 160
 161         INIT_WORK(&p->work, tape_34xx_work_handler);
 162
 163         p->device = tape_get_device(device);
 164         p->op     = op;
 165
 166         schedule_work(&p->work);
 167         return 0;
 168 }
 169
 170 /*
 171  * Done Handler is called when dev stat = DEVICE-END (successful operation)
 172  */
 173 static inline int
 174 tape_34xx_done(struct tape_request *request)
 175 {
 176         DBF_EVENT(6, "%s done\n", tape_op_verbose[request->op]);
 177
 178         switch (request->op) {
 179                 case TO_DSE:
 180                 case TO_RUN:
 181                 case TO_WRI:
 182                 case TO_WTM:
 183                 case TO_ASSIGN:
 184                 case TO_UNASSIGN:
 185                         tape_34xx_delete_sbid_from(request->device, 0);
 186                         break;
 187                 default:
 188                         ;
 189         }
 190         return TAPE_IO_SUCCESS;
 191 }
 192
 193 static inline int
 194 tape_34xx_erp_failed(struct tape_request *request, int rc)
 195 {
 196         DBF_EVENT(3, "Error recovery failed for %s (RC=%d)\n",
 197                   tape_op_verbose[request->op], rc);
 198         return rc;
 199 }
 200
 201 static inline int
 202 tape_34xx_erp_succeeded(struct tape_request *request)
 203 {
 204         DBF_EVENT(3, "Error Recovery successful for %s\n",
 205                   tape_op_verbose[request->op]);
 206         return tape_34xx_done(request);
 207 }
 208
 209 static inline int
 210 tape_34xx_erp_retry(struct tape_request *request)
 211 {
 212         DBF_EVENT(3, "xerp retr %s\n", tape_op_verbose[request->op]);
 213         return TAPE_IO_RETRY;
 214 }
 215
 216 /*
 217  * This function is called, when no request is outstanding and we get an
 218  * interrupt
 219  */
 220 static int
 221 tape_34xx_unsolicited_irq(struct tape_device *device, struct irb *irb)
 222 {
 223         if (irb->scsw.cmd.dstat == 0x85) { /* READY */
 224                 /* A medium was inserted in the drive. */
 225                 DBF_EVENT(6, "xuud med\n");
 226                 tape_34xx_delete_sbid_from(device, 0);
 227                 tape_34xx_schedule_work(device, TO_MSEN);
 228         } else {
 229                 DBF_EVENT(3, "unsol.irq! dev end: %08x\n", device->cdev_id);
 230                 tape_dump_sense_dbf(device, NULL, irb);
 231         }
 232         return TAPE_IO_SUCCESS;
 233 }
 234
 235 /*
 236  * Read Opposite Error Recovery Function:
 237  * Used, when Read Forward does not work
 238  */
 239 static int
 240 tape_34xx_erp_read_opposite(struct tape_device *device,
 241                             struct tape_request *request)
 242 {
 243         if (request->op == TO_RFO) {
 244                 /*
 245                  * We did read forward, but the data could not be read
 246                  * *correctly*. We transform the request to a read backward
 247                  * and try again.
 248                  */
 249                 tape_std_read_backward(device, request);
 250                 return tape_34xx_erp_retry(request);
 251         }
 252
 253         /*
 254          * We tried to read forward and backward, but hat no
 255          * success -> failed.
 256          */
 257         return tape_34xx_erp_failed(request, -EIO);
 258 }
 259
 260 static int
 261 tape_34xx_erp_bug(struct tape_device *device, struct tape_request *request,
 262                   struct irb *irb, int no)
 263 {
 264         if (request->op != TO_ASSIGN) {
 265                 dev_err(&device->cdev->dev, "An unexpected condition %d "
 266                         "occurred in tape error recovery\n", no);
 267                 tape_dump_sense_dbf(device, request, irb);
 268         }
 269         return tape_34xx_erp_failed(request, -EIO);
 270 }
 271
 272 /*
 273  * Handle data overrun between cu and drive. The channel speed might
 274  * be too slow.
 275  */
 276 static int
 277 tape_34xx_erp_overrun(struct tape_device *device, struct tape_request *request,
 278                       struct irb *irb)
 279 {
 280         if (irb->ecw[3] == 0x40) {
 281                 dev_warn (&device->cdev->dev, "A data overrun occurred between"
 282                         " the control unit and tape unit\n");
 283                 return tape_34xx_erp_failed(request, -EIO);
 284         }
 285         return tape_34xx_erp_bug(device, request, irb, -1);
 286 }
 287
 288 /*
 289  * Handle record sequence error.
 290  */
 291 static int
 292 tape_34xx_erp_sequence(struct tape_device *device,
 293                        struct tape_request *request, struct irb *irb)
 294 {
 295         if (irb->ecw[3] == 0x41) {
 296                 /*
 297                  * cu detected incorrect block-id sequence on tape.
 298                  */
 299                 dev_warn (&device->cdev->dev, "The block ID sequence on the "
 300                         "tape is incorrect\n");
 301                 return tape_34xx_erp_failed(request, -EIO);
 302         }
 303         /*
 304          * Record sequence error bit is set, but erpa does not
 305          * show record sequence error.
 306          */
 307         return tape_34xx_erp_bug(device, request, irb, -2);
 308 }
 309
 310 /*
 311  * This function analyses the tape's sense-data in case of a unit-check.
 312  * If possible, it tries to recover from the error. Else the user is
 313  * informed about the problem.
 314  */
 315 static int
 316 tape_34xx_unit_check(struct tape_device *device, struct tape_request *request,
 317                      struct irb *irb)
 318 {
 319         int inhibit_cu_recovery;
 320         __u8* sense;
 321
 322         inhibit_cu_recovery = (*device->modeset_byte & 0x80) ? 1 : 0;
 323         sense = irb->ecw;
 324
 325         if (
 326                 sense[0] & SENSE_COMMAND_REJECT &&
 327                 sense[1] & SENSE_WRITE_PROTECT
 328         ) {
 329                 if (
 330                         request->op == TO_DSE ||
 331                         request->op == TO_WRI ||
 332                         request->op == TO_WTM
 333                 ) {
 334                         /* medium is write protected */
 335                         return tape_34xx_erp_failed(request, -EACCES);
 336                 } else {
 337                         return tape_34xx_erp_bug(device, request, irb, -3);
 338                 }
 339         }
 340
 341         /*
 342          * Special cases for various tape-states when reaching
 343          * end of recorded area
 344          *
 345          * FIXME: Maybe a special case of the special case:
 346          *        sense[0] == SENSE_EQUIPMENT_CHECK &&
 347          *        sense[1] == SENSE_DRIVE_ONLINE    &&
 348          *        sense[3] == 0x47 (Volume Fenced)
 349          *
 350          *        This was caused by continued FSF or FSR after an
 351          *        'End Of Data'.
 352          */
 353         if ((
 354                 sense[0] == SENSE_DATA_CHECK      ||
 355                 sense[0] == SENSE_EQUIPMENT_CHECK ||
 356                 sense[0] == SENSE_EQUIPMENT_CHECK + SENSE_DEFERRED_UNIT_CHECK
 357         ) && (
 358                 sense[1] == SENSE_DRIVE_ONLINE ||
 359                 sense[1] == SENSE_BEGINNING_OF_TAPE + SENSE_WRITE_MODE
 360         )) {
 361                 switch (request->op) {
 362                 /*
 363                  * sense[0] == SENSE_DATA_CHECK   &&
 364                  * sense[1] == SENSE_DRIVE_ONLINE
 365                  * sense[3] == 0x36 (End Of Data)
 366                  *
 367                  * Further seeks might return a 'Volume Fenced'.
 368                  */
 369                 case TO_FSF:
 370                 case TO_FSB:
 371                         /* Trying to seek beyond end of recorded area */
 372                         return tape_34xx_erp_failed(request, -ENOSPC);
 373                 case TO_BSB:
 374                         return tape_34xx_erp_retry(request);
 375
 376                 /*
 377                  * sense[0] == SENSE_DATA_CHECK   &&
 378                  * sense[1] == SENSE_DRIVE_ONLINE &&
 379                  * sense[3] == 0x36 (End Of Data)
 380                  */
 381                 case TO_LBL:
 382                         /* Block could not be located. */
 383                         tape_34xx_delete_sbid_from(device, 0);
 384                         return tape_34xx_erp_failed(request, -EIO);
 385
 386                 case TO_RFO:
 387                         /* Read beyond end of recorded area -> 0 bytes read */
 388                         return tape_34xx_erp_failed(request, 0);
 389
 390                 /*
 391                  * sense[0] == SENSE_EQUIPMENT_CHECK &&
 392                  * sense[1] == SENSE_DRIVE_ONLINE    &&
 393                  * sense[3] == 0x38 (Physical End Of Volume)
 394                  */
 395                 case TO_WRI:
 396                         /* Writing at physical end of volume */
 397                         return tape_34xx_erp_failed(request, -ENOSPC);
 398                 default:
 399                         return tape_34xx_erp_failed(request, 0);
 400                 }
 401         }
 402
 403         /* Sensing special bits */
 404         if (sense[0] & SENSE_BUS_OUT_CHECK)
 405                 return tape_34xx_erp_retry(request);
 406
 407         if (sense[0] & SENSE_DATA_CHECK) {
 408                 /*
 409                  * hardware failure, damaged tape or improper
 410                  * operating conditions
 411                  */
 412                 switch (sense[3]) {
 413                 case 0x23:
 414                         /* a read data check occurred */
 415                         if ((sense[2] & SENSE_TAPE_SYNC_MODE) ||
 416                             inhibit_cu_recovery)
 417                                 // data check is not permanent, may be
 418                                 // recovered. We always use async-mode with
 419                                 // cu-recovery, so this should *never* happen.
 420                                 return tape_34xx_erp_bug(device, request,
 421                                                          irb, -4);
 422
 423                         /* data check is permanent, CU recovery has failed */
 424                         dev_warn (&device->cdev->dev, "A read error occurred "
 425                                 "that cannot be recovered\n");
 426                         return tape_34xx_erp_failed(request, -EIO);
 427                 case 0x25:
 428                         // a write data check occurred
 429                         if ((sense[2] & SENSE_TAPE_SYNC_MODE) ||
 430                             inhibit_cu_recovery)
 431                                 // data check is not permanent, may be
 432                                 // recovered. We always use async-mode with
 433                                 // cu-recovery, so this should *never* happen.
 434                                 return tape_34xx_erp_bug(device, request,
 435                                                          irb, -5);
 436
 437                         // data check is permanent, cu-recovery has failed
 438                         dev_warn (&device->cdev->dev, "A write error on the "
 439                                 "tape cannot be recovered\n");
 440                         return tape_34xx_erp_failed(request, -EIO);
 441                 case 0x26:
 442                         /* Data Check (read opposite) occurred. */
 443                         return tape_34xx_erp_read_opposite(device, request);
 444                 case 0x28:
 445                         /* ID-Mark at tape start couldn't be written */
 446                         dev_warn (&device->cdev->dev, "Writing the ID-mark "
 447                                 "failed\n");
 448                         return tape_34xx_erp_failed(request, -EIO);
 449                 case 0x31:
 450                         /* Tape void. Tried to read beyond end of device. */
 451                         dev_warn (&device->cdev->dev, "Reading the tape beyond"
 452                                 " the end of the recorded area failed\n");
 453                         return tape_34xx_erp_failed(request, -ENOSPC);
 454                 case 0x41:
 455                         /* Record sequence error. */
 456                         dev_warn (&device->cdev->dev, "The tape contains an "
 457                                 "incorrect block ID sequence\n");
 458                         return tape_34xx_erp_failed(request, -EIO);
 459                 default:
 460                         /* all data checks for 3480 should result in one of
 461                          * the above erpa-codes. For 3490, other data-check
 462                          * conditions do exist. */
 463                         if (device->cdev->id.driver_info == tape_3480)
 464                                 return tape_34xx_erp_bug(device, request,
 465                                                          irb, -6);
 466                 }
 467         }
 468
 469         if (sense[0] & SENSE_OVERRUN)
 470                 return tape_34xx_erp_overrun(device, request, irb);
 471
 472         if (sense[1] & SENSE_RECORD_SEQUENCE_ERR)
 473                 return tape_34xx_erp_sequence(device, request, irb);
 474
 475         /* Sensing erpa codes */
 476         switch (sense[3]) {
 477         case 0x00:
 478                 /* Unit check with erpa code 0. Report and ignore. */
 479                 return TAPE_IO_SUCCESS;
 480         case 0x21:
 481                 /*
 482                  * Data streaming not operational. CU will switch to
 483                  * interlock mode. Reissue the command.
 484                  */
 485                 return tape_34xx_erp_retry(request);
 486         case 0x22:
 487                 /*
 488                  * Path equipment check. Might be drive adapter error, buffer
 489                  * error on the lower interface, internal path not usable,
 490                  * or error during cartridge load.
 491                  */
 492                 dev_warn (&device->cdev->dev, "A path equipment check occurred"
 493                         " for the tape device\n");
 494                 return tape_34xx_erp_failed(request, -EIO);
 495         case 0x24:
 496                 /*
 497                  * Load display check. Load display was command was issued,
 498                  * but the drive is displaying a drive check message. Can
 499                  * be threated as "device end".
 500                  */
 501                 return tape_34xx_erp_succeeded(request);
 502         case 0x27:
 503                 /*
 504                  * Command reject. May indicate illegal channel program or
 505                  * buffer over/underrun. Since all channel programs are
 506                  * issued by this driver and ought be correct, we assume a
 507                  * over/underrun situation and retry the channel program.
 508                  */
 509                 return tape_34xx_erp_retry(request);
 510         case 0x29:
 511                 /*
 512                  * Function incompatible. Either the tape is idrc compressed
 513                  * but the hardware isn't capable to do idrc, or a perform
 514                  * subsystem func is issued and the CU is not on-line.
 515                  */
 516                 return tape_34xx_erp_failed(request, -EIO);
 517         case 0x2a:
 518                 /*
 519                  * Unsolicited environmental data. An internal counter
 520                  * overflows, we can ignore this and reissue the cmd.
 521                  */
 522                 return tape_34xx_erp_retry(request);
 523         case 0x2b:
 524                 /*
 525                  * Environmental data present. Indicates either unload
 526                  * completed ok or read buffered log command completed ok.
 527                  */
 528                 if (request->op == TO_RUN) {
 529                         /* Rewind unload completed ok. */
 530                         tape_med_state_set(device, MS_UNLOADED);
 531                         return tape_34xx_erp_succeeded(request);
 532                 }
 533                 /* tape_34xx doesn't use read buffered log commands. */
 534                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 535         case 0x2c:
 536                 /*
 537                  * Permanent equipment check. CU has tried recovery, but
 538                  * did not succeed.
 539                  */
 540                 return tape_34xx_erp_failed(request, -EIO);
 541         case 0x2d:
 542                 /* Data security erase failure. */
 543                 if (request->op == TO_DSE)
 544                         return tape_34xx_erp_failed(request, -EIO);
 545                 /* Data security erase failure, but no such command issued. */
 546                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 547         case 0x2e:
 548                 /*
 549                  * Not capable. This indicates either that the drive fails
 550                  * reading the format id mark or that that format specified
 551                  * is not supported by the drive.
 552                  */
 553                 dev_warn (&device->cdev->dev, "The tape unit cannot process "
 554                         "the tape format\n");
 555                 return tape_34xx_erp_failed(request, -EMEDIUMTYPE);
 556         case 0x30:
 557                 /* The medium is write protected. */
 558                 dev_warn (&device->cdev->dev, "The tape medium is write-"
 559                         "protected\n");
 560                 return tape_34xx_erp_failed(request, -EACCES);
 561         case 0x32:
 562                 // Tension loss. We cannot recover this, it's an I/O error.
 563                 dev_warn (&device->cdev->dev, "The tape does not have the "
 564                         "required tape tension\n");
 565                 return tape_34xx_erp_failed(request, -EIO);
 566         case 0x33:
 567                 /*
 568                  * Load Failure. The cartridge was not inserted correctly or
 569                  * the tape is not threaded correctly.
 570                  */
 571                 dev_warn (&device->cdev->dev, "The tape unit failed to load"
 572                         " the cartridge\n");
 573                 tape_34xx_delete_sbid_from(device, 0);
 574                 return tape_34xx_erp_failed(request, -EIO);
 575         case 0x34:
 576                 /*
 577                  * Unload failure. The drive cannot maintain tape tension
 578                  * and control tape movement during an unload operation.
 579                  */
 580                 dev_warn (&device->cdev->dev, "Automatic unloading of the tape"
 581                         " cartridge failed\n");
 582                 if (request->op == TO_RUN)
 583                         return tape_34xx_erp_failed(request, -EIO);
 584                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 585         case 0x35:
 586                 /*
 587                  * Drive equipment check. One of the following:
 588                  * - cu cannot recover from a drive detected error
 589                  * - a check code message is shown on drive display
 590                  * - the cartridge loader does not respond correctly
 591                  * - a failure occurs during an index, load, or unload cycle
 592                  */
 593                 dev_warn (&device->cdev->dev, "An equipment check has occurred"
 594                         " on the tape unit\n");
 595                 return tape_34xx_erp_failed(request, -EIO);
 596         case 0x36:
 597                 if (device->cdev->id.driver_info == tape_3490)
 598                         /* End of data. */
 599                         return tape_34xx_erp_failed(request, -EIO);
 600                 /* This erpa is reserved for 3480 */
 601                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 602         case 0x37:
 603                 /*
 604                  * Tape length error. The tape is shorter than reported in
 605                  * the beginning-of-tape data.
 606                  */
 607                 dev_warn (&device->cdev->dev, "The tape information states an"
 608                         " incorrect length\n");
 609                 return tape_34xx_erp_failed(request, -EIO);
 610         case 0x38:
 611                 /*
 612                  * Physical end of tape. A read/write operation reached
 613                  * the physical end of tape.
 614                  */
 615                 if (request->op==TO_WRI ||
 616                     request->op==TO_DSE ||
 617                     request->op==TO_WTM)
 618                         return tape_34xx_erp_failed(request, -ENOSPC);
 619                 return tape_34xx_erp_failed(request, -EIO);
 620         case 0x39:
 621                 /* Backward at Beginning of tape. */
 622                 return tape_34xx_erp_failed(request, -EIO);
 623         case 0x3a:
 624                 /* Drive switched to not ready. */
 625                 dev_warn (&device->cdev->dev, "The tape unit is not ready\n");
 626                 return tape_34xx_erp_failed(request, -EIO);
 627         case 0x3b:
 628                 /* Manual rewind or unload. This causes an I/O error. */
 629                 dev_warn (&device->cdev->dev, "The tape medium has been "
 630                         "rewound or unloaded manually\n");
 631                 tape_34xx_delete_sbid_from(device, 0);
 632                 return tape_34xx_erp_failed(request, -EIO);
 633         case 0x42:
 634                 /*
 635                  * Degraded mode. A condition that can cause degraded
 636                  * performance is detected.
 637                  */
 638                 dev_warn (&device->cdev->dev, "The tape subsystem is running "
 639                         "in degraded mode\n");
 640                 return tape_34xx_erp_retry(request);
 641         case 0x43:
 642                 /* Drive not ready. */
 643                 tape_34xx_delete_sbid_from(device, 0);
 644                 tape_med_state_set(device, MS_UNLOADED);
 645                 /* Some commands commands are successful even in this case */
 646                 if (sense[1] & SENSE_DRIVE_ONLINE) {
 647                         switch(request->op) {
 648                                 case TO_ASSIGN:
 649                                 case TO_UNASSIGN:
 650                                 case TO_DIS:
 651                                 case TO_NOP:
 652                                         return tape_34xx_done(request);
 653                                         break;
 654                                 default:
 655                                         break;
 656                         }
 657                 }
 658                 return tape_34xx_erp_failed(request, -ENOMEDIUM);
 659         case 0x44:
 660                 /* Locate Block unsuccessful. */
 661                 if (request->op != TO_BLOCK && request->op != TO_LBL)
 662                         /* No locate block was issued. */
 663                         return tape_34xx_erp_bug(device, request,
 664                                                  irb, sense[3]);
 665                 return tape_34xx_erp_failed(request, -EIO);
 666         case 0x45:
 667                 /* The drive is assigned to a different channel path. */
 668                 dev_warn (&device->cdev->dev, "The tape unit is already "
 669                         "assigned\n");
 670                 return tape_34xx_erp_failed(request, -EIO);
 671         case 0x46:
 672                 /*
 673                  * Drive not on-line. Drive may be switched offline,
 674                  * the power supply may be switched off or
 675                  * the drive address may not be set correctly.
 676                  */
 677                 dev_warn (&device->cdev->dev, "The tape unit is not online\n");
 678                 return tape_34xx_erp_failed(request, -EIO);
 679         case 0x47:
 680                 /* Volume fenced. CU reports volume integrity is lost. */
 681                 dev_warn (&device->cdev->dev, "The control unit has fenced "
 682                         "access to the tape volume\n");
 683                 tape_34xx_delete_sbid_from(device, 0);
 684                 return tape_34xx_erp_failed(request, -EIO);
 685         case 0x48:
 686                 /* Log sense data and retry request. */
 687                 return tape_34xx_erp_retry(request);
 688         case 0x49:
 689                 /* Bus out check. A parity check error on the bus was found. */
 690                 dev_warn (&device->cdev->dev, "A parity error occurred on the "
 691                         "tape bus\n");
 692                 return tape_34xx_erp_failed(request, -EIO);
 693         case 0x4a:
 694                 /* Control unit erp failed. */
 695                 dev_warn (&device->cdev->dev, "I/O error recovery failed on "
 696                         "the tape control unit\n");
 697                 return tape_34xx_erp_failed(request, -EIO);
 698         case 0x4b:
 699                 /*
 700                  * CU and drive incompatible. The drive requests micro-program
 701                  * patches, which are not available on the CU.
 702                  */
 703                 dev_warn (&device->cdev->dev, "The tape unit requires a "
 704                         "firmware update\n");
 705                 return tape_34xx_erp_failed(request, -EIO);
 706         case 0x4c:
 707                 /*
 708                  * Recovered Check-One failure. Cu develops a hardware error,
 709                  * but is able to recover.
 710                  */
 711                 return tape_34xx_erp_retry(request);
 712         case 0x4d:
 713                 if (device->cdev->id.driver_info == tape_3490)
 714                         /*
 715                          * Resetting event received. Since the driver does
 716                          * not support resetting event recovery (which has to
 717                          * be handled by the I/O Layer), retry our command.
 718                          */
 719                         return tape_34xx_erp_retry(request);
 720                 /* This erpa is reserved for 3480. */
 721                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 722         case 0x4e:
 723                 if (device->cdev->id.driver_info == tape_3490) {
 724                         /*
 725                          * Maximum block size exceeded. This indicates, that
 726                          * the block to be written is larger than allowed for
 727                          * buffered mode.
 728                          */
 729                         dev_warn (&device->cdev->dev, "The maximum block size"
 730                                 " for buffered mode is exceeded\n");
 731                         return tape_34xx_erp_failed(request, -ENOBUFS);
 732                 }
 733                 /* This erpa is reserved for 3480. */
 734                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 735         case 0x50:
 736                 /*
 737                  * Read buffered log (Overflow). CU is running in extended
 738                  * buffered log mode, and a counter overflows. This should
 739                  * never happen, since we're never running in extended
 740                  * buffered log mode.
 741                  */
 742                 return tape_34xx_erp_retry(request);
 743         case 0x51:
 744                 /*
 745                  * Read buffered log (EOV). EOF processing occurs while the
 746                  * CU is in extended buffered log mode. This should never
 747                  * happen, since we're never running in extended buffered
 748                  * log mode.
 749                  */
 750                 return tape_34xx_erp_retry(request);
 751         case 0x52:
 752                 /* End of Volume complete. Rewind unload completed ok. */
 753                 if (request->op == TO_RUN) {
 754                         tape_med_state_set(device, MS_UNLOADED);
 755                         tape_34xx_delete_sbid_from(device, 0);
 756                         return tape_34xx_erp_succeeded(request);
 757                 }
 758                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 759         case 0x53:
 760                 /* Global command intercept. */
 761                 return tape_34xx_erp_retry(request);
 762         case 0x54:
 763                 /* Channel interface recovery (temporary). */
 764                 return tape_34xx_erp_retry(request);
 765         case 0x55:
 766                 /* Channel interface recovery (permanent). */
 767                 dev_warn (&device->cdev->dev, "A channel interface error cannot be"
 768                         " recovered\n");
 769                 return tape_34xx_erp_failed(request, -EIO);
 770         case 0x56:
 771                 /* Channel protocol error. */
 772                 dev_warn (&device->cdev->dev, "A channel protocol error "
 773                         "occurred\n");
 774                 return tape_34xx_erp_failed(request, -EIO);
 775         case 0x57:
 776                 /*
 777                  * 3480: Attention intercept.
 778                  * 3490: Global status intercept.
 779                  */
 780                 return tape_34xx_erp_retry(request);
 781         case 0x5a:
 782                 /*
 783                  * Tape length incompatible. The tape inserted is too long,
 784                  * which could cause damage to the tape or the drive.
 785                  */
 786                 dev_warn (&device->cdev->dev, "The tape unit does not support "
 787                         "the tape length\n");
 788                 return tape_34xx_erp_failed(request, -EIO);
 789         case 0x5b:
 790                 /* Format 3480 XF incompatible */
 791                 if (sense[1] & SENSE_BEGINNING_OF_TAPE)
 792                         /* The tape will get overwritten. */
 793                         return tape_34xx_erp_retry(request);
 794                 dev_warn (&device->cdev->dev, "The tape unit does not support"
 795                         " format 3480 XF\n");
 796                 return tape_34xx_erp_failed(request, -EIO);
 797         case 0x5c:
 798                 /* Format 3480-2 XF incompatible */
 799                 dev_warn (&device->cdev->dev, "The tape unit does not support tape "
 800                         "format 3480-2 XF\n");
 801                 return tape_34xx_erp_failed(request, -EIO);
 802         case 0x5d:
 803                 /* Tape length violation. */
 804                 dev_warn (&device->cdev->dev, "The tape unit does not support"
 805                         " the current tape length\n");
 806                 return tape_34xx_erp_failed(request, -EMEDIUMTYPE);
 807         case 0x5e:
 808                 /* Compaction algorithm incompatible. */
 809                 dev_warn (&device->cdev->dev, "The tape unit does not support"
 810                         " the compaction algorithm\n");
 811                 return tape_34xx_erp_failed(request, -EMEDIUMTYPE);
 812
 813                 /* The following erpas should have been covered earlier. */
 814         case 0x23: /* Read data check. */
 815         case 0x25: /* Write data check. */
 816         case 0x26: /* Data check (read opposite). */
 817         case 0x28: /* Write id mark check. */
 818         case 0x31: /* Tape void. */
 819         case 0x40: /* Overrun error. */
 820         case 0x41: /* Record sequence error. */
 821                 /* All other erpas are reserved for future use. */
 822         default:
 823                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 824         }
 825 }
 826
 827 /*
 828  * 3480/3490 interrupt handler
 829  */
 830 static int
 831 tape_34xx_irq(struct tape_device *device, struct tape_request *request,
 832               struct irb *irb)
 833 {
 834         if (request == NULL)
 835                 return tape_34xx_unsolicited_irq(device, irb);
 836
 837         if ((irb->scsw.cmd.dstat & DEV_STAT_UNIT_EXCEP) &&
 838             (irb->scsw.cmd.dstat & DEV_STAT_DEV_END) &&
 839             (request->op == TO_WRI)) {
 840                 /* Write at end of volume */
 841                 return tape_34xx_erp_failed(request, -ENOSPC);
 842         }
 843
 844         if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)
 845                 return tape_34xx_unit_check(device, request, irb);
 846
 847         if (irb->scsw.cmd.dstat & DEV_STAT_DEV_END) {
 848                 /*
 849                  * A unit exception occurs on skipping over a tapemark block.
 850                  */
 851                 if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_EXCEP) {
 852                         if (request->op == TO_BSB || request->op == TO_FSB)
 853                                 request->rescnt++;
 854                         else
 855                                 DBF_EVENT(5, "Unit Exception!\n");
 856                 }
 857                 return tape_34xx_done(request);
 858         }
 859
 860         DBF_EVENT(6, "xunknownirq\n");
 861         tape_dump_sense_dbf(device, request, irb);
 862         return TAPE_IO_STOP;
 863 }
 864
 865 /*
 866  * ioctl_overload
 867  */
 868 static int
 869 tape_34xx_ioctl(struct tape_device *device, unsigned int cmd, unsigned long arg)
 870 {
 871         if (cmd == TAPE390_DISPLAY) {
 872                 struct display_struct disp;
 873
 874                 if (copy_from_user(&disp, (char __user *) arg, sizeof(disp)) != 0)
 875                         return -EFAULT;
 876
 877                 return tape_std_display(device, &disp);
 878         } else
 879                 return -EINVAL;
 880 }
 881
 882 static inline void
 883 tape_34xx_append_new_sbid(struct tape_34xx_block_id bid, struct list_head *l)
 884 {
 885         struct tape_34xx_sbid * new_sbid;
 886
 887         new_sbid = kmalloc(sizeof(*new_sbid), GFP_ATOMIC);
 888         if (!new_sbid)
 889                 return;
 890
 891         new_sbid->bid = bid;
 892         list_add(&new_sbid->list, l);
 893 }
 894
 895 /*
 896  * Build up the search block ID list. The block ID consists of a logical
 897  * block number and a hardware specific part. The hardware specific part
 898  * helps the tape drive to speed up searching for a specific block.
 899  */
 900 static void
 901 tape_34xx_add_sbid(struct tape_device *device, struct tape_34xx_block_id bid)
 902 {
 903         struct list_head *      sbid_list;
 904         struct tape_34xx_sbid * sbid;
 905         struct list_head *      l;
 906
 907         /*
 908          * immediately return if there is no list at all or the block to add
 909          * is located in segment 1 of wrap 0 because this position is used
 910          * if no hardware position data is supplied.
 911          */
 912         sbid_list = (struct list_head *) device->discdata;
 913         if (!sbid_list || (bid.segment < 2 && bid.wrap == 0))
 914                 return;
 915
 916         /*
 917          * Search the position where to insert the new entry. Hardware
 918          * acceleration uses only the segment and wrap number. So we
 919          * need only one entry for a specific wrap/segment combination.
 920          * If there is a block with a lower number but the same hard-
 921          * ware position data we just update the block number in the
 922          * existing entry.
 923          */
 924         list_for_each(l, sbid_list) {
 925                 sbid = list_entry(l, struct tape_34xx_sbid, list);
 926
 927                 if (
 928                         (sbid->bid.segment == bid.segment) &&
 929                         (sbid->bid.wrap    == bid.wrap)
 930                 ) {
 931                         if (bid.block < sbid->bid.block)
 932                                 sbid->bid = bid;
 933                         else return;
 934                         break;
 935                 }
 936
 937                 /* Sort in according to logical block number. */
 938                 if (bid.block < sbid->bid.block) {
 939                         tape_34xx_append_new_sbid(bid, l->prev);
 940                         break;
 941                 }
 942         }
 943         /* List empty or new block bigger than last entry. */
 944         if (l == sbid_list)
 945                 tape_34xx_append_new_sbid(bid, l->prev);
 946
 947         DBF_LH(4, "Current list is:\n");
 948         list_for_each(l, sbid_list) {
 949                 sbid = list_entry(l, struct tape_34xx_sbid, list);
 950                 DBF_LH(4, "%d:%03d@%05d\n",
 951                         sbid->bid.wrap,
 952                         sbid->bid.segment,
 953                         sbid->bid.block
 954                 );
 955         }
 956 }
 957
 958 /*
 959  * Delete all entries from the search block ID list that belong to tape blocks
 960  * equal or higher than the given number.
 961  */
 962 static void
 963 tape_34xx_delete_sbid_from(struct tape_device *device, int from)
 964 {
 965         struct list_head *      sbid_list;
 966         struct tape_34xx_sbid * sbid;
 967         struct list_head *      l;
 968         struct list_head *      n;
 969
 970         sbid_list = (struct list_head *) device->discdata;
 971         if (!sbid_list)
 972                 return;
 973
 974         list_for_each_safe(l, n, sbid_list) {
 975                 sbid = list_entry(l, struct tape_34xx_sbid, list);
 976                 if (sbid->bid.block >= from) {
 977                         DBF_LH(4, "Delete sbid %d:%03d@%05d\n",
 978                                 sbid->bid.wrap,
 979                                 sbid->bid.segment,
 980                                 sbid->bid.block
 981                         );
 982                         list_del(l);
 983                         kfree(sbid);
 984                 }
 985         }
 986 }
 987
 988 /*
 989  * Merge hardware position data into a block id.
 990  */
 991 static void
 992 tape_34xx_merge_sbid(
 993         struct tape_device *            device,
 994         struct tape_34xx_block_id *     bid
 995 ) {
 996         struct tape_34xx_sbid * sbid;
 997         struct tape_34xx_sbid * sbid_to_use;
 998         struct list_head *      sbid_list;
 999         struct list_head *      l;
1000
1001         sbid_list = (struct list_head *) device->discdata;
1002         bid->wrap    = 0;
1003         bid->segment = 1;
1004
1005         if (!sbid_list || list_empty(sbid_list))
1006                 return;
1007
1008         sbid_to_use = NULL;
1009         list_for_each(l, sbid_list) {
1010                 sbid = list_entry(l, struct tape_34xx_sbid, list);
1011
1012                 if (sbid->bid.block >= bid->block)
1013                         break;
1014                 sbid_to_use = sbid;
1015         }
1016         if (sbid_to_use) {
1017                 bid->wrap    = sbid_to_use->bid.wrap;
1018                 bid->segment = sbid_to_use->bid.segment;
1019                 DBF_LH(4, "Use %d:%03d@%05d for %05d\n",
1020                         sbid_to_use->bid.wrap,
1021                         sbid_to_use->bid.segment,
1022                         sbid_to_use->bid.block,
1023                         bid->block
1024                 );
1025         }
1026 }
1027
1028 static int
1029 tape_34xx_setup_device(struct tape_device * device)
1030 {
1031         int                     rc;
1032         struct list_head *      discdata;
1033
1034         DBF_EVENT(6, "34xx device setup\n");
1035         if ((rc = tape_std_assign(device)) == 0) {
1036                 if ((rc = tape_34xx_medium_sense(device)) != 0) {
1037                         DBF_LH(3, "34xx medium sense returned %d\n", rc);
1038                 }
1039         }
1040         discdata = kmalloc(sizeof(struct list_head), GFP_KERNEL);
1041         if (discdata) {
1042                         INIT_LIST_HEAD(discdata);
1043                         device->discdata = discdata;
1044         }
1045
1046         return rc;
1047 }
1048
1049 static void
1050 tape_34xx_cleanup_device(struct tape_device *device)
1051 {
1052         tape_std_unassign(device);
1053
1054         if (device->discdata) {
1055                 tape_34xx_delete_sbid_from(device, 0);
1056                 kfree(device->discdata);
1057                 device->discdata = NULL;
1058         }
1059 }
1060
1061
1062 /*
1063  * MTTELL: Tell block. Return the number of block relative to current file.
1064  */
1065 static int
1066 tape_34xx_mttell(struct tape_device *device, int mt_count)
1067 {
1068         struct {
1069                 struct tape_34xx_block_id       cbid;
1070                 struct tape_34xx_block_id       dbid;
1071         } __attribute__ ((packed)) block_id;
1072         int rc;
1073
1074         rc = tape_std_read_block_id(device, (__u64 *) &block_id);
1075         if (rc)
1076                 return rc;
1077
1078         tape_34xx_add_sbid(device, block_id.cbid);
1079         return block_id.cbid.block;
1080 }
1081
1082 /*
1083  * MTSEEK: seek to the specified block.
1084  */
1085 static int
1086 tape_34xx_mtseek(struct tape_device *device, int mt_count)
1087 {
1088         struct tape_request *request;
1089         struct tape_34xx_block_id *     bid;
1090
1091         if (mt_count > 0x3fffff) {
1092                 DBF_EXCEPTION(6, "xsee parm\n");
1093                 return -EINVAL;
1094         }
1095         request = tape_alloc_request(3, 4);
1096         if (IS_ERR(request))
1097                 return PTR_ERR(request);
1098
1099         /* setup ccws */
1100         request->op = TO_LBL;
1101         bid         = (struct tape_34xx_block_id *) request->cpdata;
1102         bid->format = (*device->modeset_byte & 0x08) ?
1103                         TAPE34XX_FMT_3480_XF : TAPE34XX_FMT_3480;
1104         bid->block  = mt_count;
1105         tape_34xx_merge_sbid(device, bid);
1106
1107         tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
1108         tape_ccw_cc(request->cpaddr + 1, LOCATE, 4, request->cpdata);
1109         tape_ccw_end(request->cpaddr + 2, NOP, 0, NULL);
1110
1111         /* execute it */
1112         return tape_do_io_free(device, request);
1113 }
1114
1115 /*
1116  * List of 3480/3490 magnetic tape commands.
1117  */
1118 static tape_mtop_fn tape_34xx_mtop[TAPE_NR_MTOPS] = {
1119         [MTRESET]        = tape_std_mtreset,
1120         [MTFSF]          = tape_std_mtfsf,
1121         [MTBSF]          = tape_std_mtbsf,
1122         [MTFSR]          = tape_std_mtfsr,
1123         [MTBSR]          = tape_std_mtbsr,
1124         [MTWEOF]         = tape_std_mtweof,
1125         [MTREW]          = tape_std_mtrew,
1126         [MTOFFL]         = tape_std_mtoffl,
1127         [MTNOP]          = tape_std_mtnop,
1128         [MTRETEN]        = tape_std_mtreten,
1129         [MTBSFM]         = tape_std_mtbsfm,
1130         [MTFSFM]         = tape_std_mtfsfm,
1131         [MTEOM]          = tape_std_mteom,
1132         [MTERASE]        = tape_std_mterase,
1133         [MTRAS1]         = NULL,
1134         [MTRAS2]         = NULL,
1135         [MTRAS3]         = NULL,
1136         [MTSETBLK]       = tape_std_mtsetblk,
1137         [MTSETDENSITY]   = NULL,
1138         [MTSEEK]         = tape_34xx_mtseek,
1139         [MTTELL]         = tape_34xx_mttell,
1140         [MTSETDRVBUFFER] = NULL,
1141         [MTFSS]          = NULL,
1142         [MTBSS]          = NULL,
1143         [MTWSM]          = NULL,
1144         [MTLOCK]         = NULL,
1145         [MTUNLOCK]       = NULL,
1146         [MTLOAD]         = tape_std_mtload,
1147         [MTUNLOAD]       = tape_std_mtunload,
1148         [MTCOMPRESSION]  = tape_std_mtcompression,
1149         [MTSETPART]      = NULL,
1150         [MTMKPART]       = NULL
1151 };
1152
1153 /*
1154  * Tape discipline structure for 3480 and 3490.
1155  */
1156 static struct tape_discipline tape_discipline_34xx = {
1157         .owner = THIS_MODULE,
1158         .setup_device = tape_34xx_setup_device,
1159         .cleanup_device = tape_34xx_cleanup_device,
1160         .process_eov = tape_std_process_eov,
1161         .irq = tape_34xx_irq,
1162         .read_block = tape_std_read_block,
1163         .write_block = tape_std_write_block,
1164         .ioctl_fn = tape_34xx_ioctl,
1165         .mtop_array = tape_34xx_mtop
1166 };
1167
1168 static struct ccw_device_id tape_34xx_ids[] = {
1169         { CCW_DEVICE_DEVTYPE(0x3480, 0, 0x3480, 0), .driver_info = tape_3480},
1170         { CCW_DEVICE_DEVTYPE(0x3490, 0, 0x3490, 0), .driver_info = tape_3490},
1171         { /* end of list */ },
1172 };
1173
1174 static int
1175 tape_34xx_online(struct ccw_device *cdev)
1176 {
1177         return tape_generic_online(
1178                 dev_get_drvdata(&cdev->dev),
1179                 &tape_discipline_34xx
1180         );
1181 }
1182
1183 static struct ccw_driver tape_34xx_driver = {
1184         .driver = {
1185                 .name = "tape_34xx",
1186                 .owner = THIS_MODULE,
1187         },
1188         .ids = tape_34xx_ids,
1189         .probe = tape_generic_probe,
1190         .remove = tape_generic_remove,
1191         .set_online = tape_34xx_online,
1192         .set_offline = tape_generic_offline,
1193         .freeze = tape_generic_pm_suspend,
1194         .int_class = IRQIO_TAP,
1195 };
1196
1197 static int
1198 tape_34xx_init (void)
1199 {
1200         int rc;
1201
1202         TAPE_DBF_AREA = debug_register ( "tape_34xx", 2, 2, 4*sizeof(long));
1203         debug_register_view(TAPE_DBF_AREA, &debug_sprintf_view);
1204 #ifdef DBF_LIKE_HELL
1205         debug_set_level(TAPE_DBF_AREA, 6);
1206 #endif
1207
1208         DBF_EVENT(3, "34xx init\n");
1209         /* Register driver for 3480/3490 tapes. */
1210         rc = ccw_driver_register(&tape_34xx_driver);
1211         if (rc)
1212                 DBF_EVENT(3, "34xx init failed\n");
1213         else
1214                 DBF_EVENT(3, "34xx registered\n");
1215         return rc;
1216 }
1217
1218 static void
1219 tape_34xx_exit(void)
1220 {
1221         ccw_driver_unregister(&tape_34xx_driver);
1222
1223         debug_unregister(TAPE_DBF_AREA);
1224 }
1225
1226 MODULE_DEVICE_TABLE(ccw, tape_34xx_ids);
1227 MODULE_AUTHOR("(C) 2001-2002 IBM Deutschland Entwicklung GmbH");
1228 MODULE_DESCRIPTION("Linux on zSeries channel attached 3480 tape device driver");
1229 MODULE_LICENSE("GPL");
1230
1231 module_init(tape_34xx_init);
1232 module_exit(tape_34xx_exit);