drivers/s390/char/tape_34xx.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *    tape device discipline for 3480/3490 tapes.
   4  *
   5  *    Copyright IBM Corp. 2001, 2009
   6  *    Author(s): Carsten Otte <cotte@de.ibm.com>
   7  *               Tuan Ngo-Anh <ngoanh@de.ibm.com>
   8  *               Martin Schwidefsky <schwidefsky@de.ibm.com>
   9  */
  10
  11 #define KMSG_COMPONENT "tape_34xx"
  12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  13
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/bio.h>
  17 #include <linux/workqueue.h>
  18 #include <linux/slab.h>
  19
  20 #define TAPE_DBF_AREA   tape_34xx_dbf
  21
  22 #include "tape.h"
  23 #include "tape_std.h"
  24
  25 /*
  26  * Pointer to debug area.
  27  */
  28 debug_info_t *TAPE_DBF_AREA = NULL;
  29 EXPORT_SYMBOL(TAPE_DBF_AREA);
  30
  31 #define TAPE34XX_FMT_3480       0
  32 #define TAPE34XX_FMT_3480_2_XF  1
  33 #define TAPE34XX_FMT_3480_XF    2
  34
  35 struct tape_34xx_block_id {
  36         unsigned int    wrap            : 1;
  37         unsigned int    segment         : 7;
  38         unsigned int    format          : 2;
  39         unsigned int    block           : 22;
  40 };
  41
  42 /*
  43  * A list of block ID's is used to faster seek blocks.
  44  */
  45 struct tape_34xx_sbid {
  46         struct list_head                list;
  47         struct tape_34xx_block_id       bid;
  48 };
  49
  50 static void tape_34xx_delete_sbid_from(struct tape_device *, int);
  51
  52 /*
  53  * Medium sense for 34xx tapes. There is no 'real' medium sense call.
  54  * So we just do a normal sense.
  55  */
  56 static void __tape_34xx_medium_sense(struct tape_request *request)
  57 {
  58         struct tape_device *device = request->device;
  59         unsigned char *sense;
  60
  61         if (request->rc == 0) {
  62                 sense = request->cpdata;
  63
  64                 /*
  65                  * This isn't quite correct. But since INTERVENTION_REQUIRED
  66                  * means that the drive is 'neither ready nor on-line' it is
  67                  * only slightly inaccurate to say there is no tape loaded if
  68                  * the drive isn't online...
  69                  */
  70                 if (sense[0] & SENSE_INTERVENTION_REQUIRED)
  71                         tape_med_state_set(device, MS_UNLOADED);
  72                 else
  73                         tape_med_state_set(device, MS_LOADED);
  74
  75                 if (sense[1] & SENSE_WRITE_PROTECT)
  76                         device->tape_generic_status |= GMT_WR_PROT(~0);
  77                 else
  78                         device->tape_generic_status &= ~GMT_WR_PROT(~0);
  79         } else
  80                 DBF_EVENT(4, "tape_34xx: medium sense failed with rc=%d\n",
  81                         request->rc);
  82         tape_free_request(request);
  83 }
  84
  85 static int tape_34xx_medium_sense(struct tape_device *device)
  86 {
  87         struct tape_request *request;
  88         int rc;
  89
  90         request = tape_alloc_request(1, 32);
  91         if (IS_ERR(request)) {
  92                 DBF_EXCEPTION(6, "MSEN fail\n");
  93                 return PTR_ERR(request);
  94         }
  95
  96         request->op = TO_MSEN;
  97         tape_ccw_end(request->cpaddr, SENSE, 32, request->cpdata);
  98         rc = tape_do_io_interruptible(device, request);
  99         __tape_34xx_medium_sense(request);
 100         return rc;
 101 }
 102
 103 static void tape_34xx_medium_sense_async(struct tape_device *device)
 104 {
 105         struct tape_request *request;
 106
 107         request = tape_alloc_request(1, 32);
 108         if (IS_ERR(request)) {
 109                 DBF_EXCEPTION(6, "MSEN fail\n");
 110                 return;
 111         }
 112
 113         request->op = TO_MSEN;
 114         tape_ccw_end(request->cpaddr, SENSE, 32, request->cpdata);
 115         request->callback = (void *) __tape_34xx_medium_sense;
 116         request->callback_data = NULL;
 117         tape_do_io_async(device, request);
 118 }
 119
 120 struct tape_34xx_work {
 121         struct tape_device      *device;
 122         enum tape_op             op;
 123         struct work_struct       work;
 124 };
 125
 126 /*
 127  * These functions are currently used only to schedule a medium_sense for
 128  * later execution. This is because we get an interrupt whenever a medium
 129  * is inserted but cannot call tape_do_io* from an interrupt context.
 130  * Maybe that's useful for other actions we want to start from the
 131  * interrupt handler.
 132  * Note: the work handler is called by the system work queue. The tape
 133  * commands started by the handler need to be asynchrounous, otherwise
 134  * a deadlock can occur e.g. in case of a deferred cc=1 (see __tape_do_irq).
 135  */
 136 static void
 137 tape_34xx_work_handler(struct work_struct *work)
 138 {
 139         struct tape_34xx_work *p =
 140                 container_of(work, struct tape_34xx_work, work);
 141         struct tape_device *device = p->device;
 142
 143         switch(p->op) {
 144                 case TO_MSEN:
 145                         tape_34xx_medium_sense_async(device);
 146                         break;
 147                 default:
 148                         DBF_EVENT(3, "T34XX: internal error: unknown work\n");
 149         }
 150         tape_put_device(device);
 151         kfree(p);
 152 }
 153
 154 static int
 155 tape_34xx_schedule_work(struct tape_device *device, enum tape_op op)
 156 {
 157         struct tape_34xx_work *p;
 158
 159         if ((p = kzalloc(sizeof(*p), GFP_ATOMIC)) == NULL)
 160                 return -ENOMEM;
 161
 162         INIT_WORK(&p->work, tape_34xx_work_handler);
 163
 164         p->device = tape_get_device(device);
 165         p->op     = op;
 166
 167         schedule_work(&p->work);
 168         return 0;
 169 }
 170
 171 /*
 172  * Done Handler is called when dev stat = DEVICE-END (successful operation)
 173  */
 174 static inline int
 175 tape_34xx_done(struct tape_request *request)
 176 {
 177         DBF_EVENT(6, "%s done\n", tape_op_verbose[request->op]);
 178
 179         switch (request->op) {
 180                 case TO_DSE:
 181                 case TO_RUN:
 182                 case TO_WRI:
 183                 case TO_WTM:
 184                 case TO_ASSIGN:
 185                 case TO_UNASSIGN:
 186                         tape_34xx_delete_sbid_from(request->device, 0);
 187                         break;
 188                 default:
 189                         ;
 190         }
 191         return TAPE_IO_SUCCESS;
 192 }
 193
 194 static inline int
 195 tape_34xx_erp_failed(struct tape_request *request, int rc)
 196 {
 197         DBF_EVENT(3, "Error recovery failed for %s (RC=%d)\n",
 198                   tape_op_verbose[request->op], rc);
 199         return rc;
 200 }
 201
 202 static inline int
 203 tape_34xx_erp_succeeded(struct tape_request *request)
 204 {
 205         DBF_EVENT(3, "Error Recovery successful for %s\n",
 206                   tape_op_verbose[request->op]);
 207         return tape_34xx_done(request);
 208 }
 209
 210 static inline int
 211 tape_34xx_erp_retry(struct tape_request *request)
 212 {
 213         DBF_EVENT(3, "xerp retr %s\n", tape_op_verbose[request->op]);
 214         return TAPE_IO_RETRY;
 215 }
 216
 217 /*
 218  * This function is called, when no request is outstanding and we get an
 219  * interrupt
 220  */
 221 static int
 222 tape_34xx_unsolicited_irq(struct tape_device *device, struct irb *irb)
 223 {
 224         if (irb->scsw.cmd.dstat == 0x85) { /* READY */
 225                 /* A medium was inserted in the drive. */
 226                 DBF_EVENT(6, "xuud med\n");
 227                 tape_34xx_delete_sbid_from(device, 0);
 228                 tape_34xx_schedule_work(device, TO_MSEN);
 229         } else {
 230                 DBF_EVENT(3, "unsol.irq! dev end: %08x\n", device->cdev_id);
 231                 tape_dump_sense_dbf(device, NULL, irb);
 232         }
 233         return TAPE_IO_SUCCESS;
 234 }
 235
 236 /*
 237  * Read Opposite Error Recovery Function:
 238  * Used, when Read Forward does not work
 239  */
 240 static int
 241 tape_34xx_erp_read_opposite(struct tape_device *device,
 242                             struct tape_request *request)
 243 {
 244         if (request->op == TO_RFO) {
 245                 /*
 246                  * We did read forward, but the data could not be read
 247                  * *correctly*. We transform the request to a read backward
 248                  * and try again.
 249                  */
 250                 tape_std_read_backward(device, request);
 251                 return tape_34xx_erp_retry(request);
 252         }
 253
 254         /*
 255          * We tried to read forward and backward, but hat no
 256          * success -> failed.
 257          */
 258         return tape_34xx_erp_failed(request, -EIO);
 259 }
 260
 261 static int
 262 tape_34xx_erp_bug(struct tape_device *device, struct tape_request *request,
 263                   struct irb *irb, int no)
 264 {
 265         if (request->op != TO_ASSIGN) {
 266                 dev_err(&device->cdev->dev, "An unexpected condition %d "
 267                         "occurred in tape error recovery\n", no);
 268                 tape_dump_sense_dbf(device, request, irb);
 269         }
 270         return tape_34xx_erp_failed(request, -EIO);
 271 }
 272
 273 /*
 274  * Handle data overrun between cu and drive. The channel speed might
 275  * be too slow.
 276  */
 277 static int
 278 tape_34xx_erp_overrun(struct tape_device *device, struct tape_request *request,
 279                       struct irb *irb)
 280 {
 281         if (irb->ecw[3] == 0x40) {
 282                 dev_warn (&device->cdev->dev, "A data overrun occurred between"
 283                         " the control unit and tape unit\n");
 284                 return tape_34xx_erp_failed(request, -EIO);
 285         }
 286         return tape_34xx_erp_bug(device, request, irb, -1);
 287 }
 288
 289 /*
 290  * Handle record sequence error.
 291  */
 292 static int
 293 tape_34xx_erp_sequence(struct tape_device *device,
 294                        struct tape_request *request, struct irb *irb)
 295 {
 296         if (irb->ecw[3] == 0x41) {
 297                 /*
 298                  * cu detected incorrect block-id sequence on tape.
 299                  */
 300                 dev_warn (&device->cdev->dev, "The block ID sequence on the "
 301                         "tape is incorrect\n");
 302                 return tape_34xx_erp_failed(request, -EIO);
 303         }
 304         /*
 305          * Record sequence error bit is set, but erpa does not
 306          * show record sequence error.
 307          */
 308         return tape_34xx_erp_bug(device, request, irb, -2);
 309 }
 310
 311 /*
 312  * This function analyses the tape's sense-data in case of a unit-check.
 313  * If possible, it tries to recover from the error. Else the user is
 314  * informed about the problem.
 315  */
 316 static int
 317 tape_34xx_unit_check(struct tape_device *device, struct tape_request *request,
 318                      struct irb *irb)
 319 {
 320         int inhibit_cu_recovery;
 321         __u8* sense;
 322
 323         inhibit_cu_recovery = (*device->modeset_byte & 0x80) ? 1 : 0;
 324         sense = irb->ecw;
 325
 326         if (
 327                 sense[0] & SENSE_COMMAND_REJECT &&
 328                 sense[1] & SENSE_WRITE_PROTECT
 329         ) {
 330                 if (
 331                         request->op == TO_DSE ||
 332                         request->op == TO_WRI ||
 333                         request->op == TO_WTM
 334                 ) {
 335                         /* medium is write protected */
 336                         return tape_34xx_erp_failed(request, -EACCES);
 337                 } else {
 338                         return tape_34xx_erp_bug(device, request, irb, -3);
 339                 }
 340         }
 341
 342         /*
 343          * Special cases for various tape-states when reaching
 344          * end of recorded area
 345          *
 346          * FIXME: Maybe a special case of the special case:
 347          *        sense[0] == SENSE_EQUIPMENT_CHECK &&
 348          *        sense[1] == SENSE_DRIVE_ONLINE    &&
 349          *        sense[3] == 0x47 (Volume Fenced)
 350          *
 351          *        This was caused by continued FSF or FSR after an
 352          *        'End Of Data'.
 353          */
 354         if ((
 355                 sense[0] == SENSE_DATA_CHECK      ||
 356                 sense[0] == SENSE_EQUIPMENT_CHECK ||
 357                 sense[0] == SENSE_EQUIPMENT_CHECK + SENSE_DEFERRED_UNIT_CHECK
 358         ) && (
 359                 sense[1] == SENSE_DRIVE_ONLINE ||
 360                 sense[1] == SENSE_BEGINNING_OF_TAPE + SENSE_WRITE_MODE
 361         )) {
 362                 switch (request->op) {
 363                 /*
 364                  * sense[0] == SENSE_DATA_CHECK   &&
 365                  * sense[1] == SENSE_DRIVE_ONLINE
 366                  * sense[3] == 0x36 (End Of Data)
 367                  *
 368                  * Further seeks might return a 'Volume Fenced'.
 369                  */
 370                 case TO_FSF:
 371                 case TO_FSB:
 372                         /* Trying to seek beyond end of recorded area */
 373                         return tape_34xx_erp_failed(request, -ENOSPC);
 374                 case TO_BSB:
 375                         return tape_34xx_erp_retry(request);
 376
 377                 /*
 378                  * sense[0] == SENSE_DATA_CHECK   &&
 379                  * sense[1] == SENSE_DRIVE_ONLINE &&
 380                  * sense[3] == 0x36 (End Of Data)
 381                  */
 382                 case TO_LBL:
 383                         /* Block could not be located. */
 384                         tape_34xx_delete_sbid_from(device, 0);
 385                         return tape_34xx_erp_failed(request, -EIO);
 386
 387                 case TO_RFO:
 388                         /* Read beyond end of recorded area -> 0 bytes read */
 389                         return tape_34xx_erp_failed(request, 0);
 390
 391                 /*
 392                  * sense[0] == SENSE_EQUIPMENT_CHECK &&
 393                  * sense[1] == SENSE_DRIVE_ONLINE    &&
 394                  * sense[3] == 0x38 (Physical End Of Volume)
 395                  */
 396                 case TO_WRI:
 397                         /* Writing at physical end of volume */
 398                         return tape_34xx_erp_failed(request, -ENOSPC);
 399                 default:
 400                         return tape_34xx_erp_failed(request, 0);
 401                 }
 402         }
 403
 404         /* Sensing special bits */
 405         if (sense[0] & SENSE_BUS_OUT_CHECK)
 406                 return tape_34xx_erp_retry(request);
 407
 408         if (sense[0] & SENSE_DATA_CHECK) {
 409                 /*
 410                  * hardware failure, damaged tape or improper
 411                  * operating conditions
 412                  */
 413                 switch (sense[3]) {
 414                 case 0x23:
 415                         /* a read data check occurred */
 416                         if ((sense[2] & SENSE_TAPE_SYNC_MODE) ||
 417                             inhibit_cu_recovery)
 418                                 // data check is not permanent, may be
 419                                 // recovered. We always use async-mode with
 420                                 // cu-recovery, so this should *never* happen.
 421                                 return tape_34xx_erp_bug(device, request,
 422                                                          irb, -4);
 423
 424                         /* data check is permanent, CU recovery has failed */
 425                         dev_warn (&device->cdev->dev, "A read error occurred "
 426                                 "that cannot be recovered\n");
 427                         return tape_34xx_erp_failed(request, -EIO);
 428                 case 0x25:
 429                         // a write data check occurred
 430                         if ((sense[2] & SENSE_TAPE_SYNC_MODE) ||
 431                             inhibit_cu_recovery)
 432                                 // data check is not permanent, may be
 433                                 // recovered. We always use async-mode with
 434                                 // cu-recovery, so this should *never* happen.
 435                                 return tape_34xx_erp_bug(device, request,
 436                                                          irb, -5);
 437
 438                         // data check is permanent, cu-recovery has failed
 439                         dev_warn (&device->cdev->dev, "A write error on the "
 440                                 "tape cannot be recovered\n");
 441                         return tape_34xx_erp_failed(request, -EIO);
 442                 case 0x26:
 443                         /* Data Check (read opposite) occurred. */
 444                         return tape_34xx_erp_read_opposite(device, request);
 445                 case 0x28:
 446                         /* ID-Mark at tape start couldn't be written */
 447                         dev_warn (&device->cdev->dev, "Writing the ID-mark "
 448                                 "failed\n");
 449                         return tape_34xx_erp_failed(request, -EIO);
 450                 case 0x31:
 451                         /* Tape void. Tried to read beyond end of device. */
 452                         dev_warn (&device->cdev->dev, "Reading the tape beyond"
 453                                 " the end of the recorded area failed\n");
 454                         return tape_34xx_erp_failed(request, -ENOSPC);
 455                 case 0x41:
 456                         /* Record sequence error. */
 457                         dev_warn (&device->cdev->dev, "The tape contains an "
 458                                 "incorrect block ID sequence\n");
 459                         return tape_34xx_erp_failed(request, -EIO);
 460                 default:
 461                         /* all data checks for 3480 should result in one of
 462                          * the above erpa-codes. For 3490, other data-check
 463                          * conditions do exist. */
 464                         if (device->cdev->id.driver_info == tape_3480)
 465                                 return tape_34xx_erp_bug(device, request,
 466                                                          irb, -6);
 467                 }
 468         }
 469
 470         if (sense[0] & SENSE_OVERRUN)
 471                 return tape_34xx_erp_overrun(device, request, irb);
 472
 473         if (sense[1] & SENSE_RECORD_SEQUENCE_ERR)
 474                 return tape_34xx_erp_sequence(device, request, irb);
 475
 476         /* Sensing erpa codes */
 477         switch (sense[3]) {
 478         case 0x00:
 479                 /* Unit check with erpa code 0. Report and ignore. */
 480                 return TAPE_IO_SUCCESS;
 481         case 0x21:
 482                 /*
 483                  * Data streaming not operational. CU will switch to
 484                  * interlock mode. Reissue the command.
 485                  */
 486                 return tape_34xx_erp_retry(request);
 487         case 0x22:
 488                 /*
 489                  * Path equipment check. Might be drive adapter error, buffer
 490                  * error on the lower interface, internal path not usable,
 491                  * or error during cartridge load.
 492                  */
 493                 dev_warn (&device->cdev->dev, "A path equipment check occurred"
 494                         " for the tape device\n");
 495                 return tape_34xx_erp_failed(request, -EIO);
 496         case 0x24:
 497                 /*
 498                  * Load display check. Load display was command was issued,
 499                  * but the drive is displaying a drive check message. Can
 500                  * be threated as "device end".
 501                  */
 502                 return tape_34xx_erp_succeeded(request);
 503         case 0x27:
 504                 /*
 505                  * Command reject. May indicate illegal channel program or
 506                  * buffer over/underrun. Since all channel programs are
 507                  * issued by this driver and ought be correct, we assume a
 508                  * over/underrun situation and retry the channel program.
 509                  */
 510                 return tape_34xx_erp_retry(request);
 511         case 0x29:
 512                 /*
 513                  * Function incompatible. Either the tape is idrc compressed
 514                  * but the hardware isn't capable to do idrc, or a perform
 515                  * subsystem func is issued and the CU is not on-line.
 516                  */
 517                 return tape_34xx_erp_failed(request, -EIO);
 518         case 0x2a:
 519                 /*
 520                  * Unsolicited environmental data. An internal counter
 521                  * overflows, we can ignore this and reissue the cmd.
 522                  */
 523                 return tape_34xx_erp_retry(request);
 524         case 0x2b:
 525                 /*
 526                  * Environmental data present. Indicates either unload
 527                  * completed ok or read buffered log command completed ok.
 528                  */
 529                 if (request->op == TO_RUN) {
 530                         /* Rewind unload completed ok. */
 531                         tape_med_state_set(device, MS_UNLOADED);
 532                         return tape_34xx_erp_succeeded(request);
 533                 }
 534                 /* tape_34xx doesn't use read buffered log commands. */
 535                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 536         case 0x2c:
 537                 /*
 538                  * Permanent equipment check. CU has tried recovery, but
 539                  * did not succeed.
 540                  */
 541                 return tape_34xx_erp_failed(request, -EIO);
 542         case 0x2d:
 543                 /* Data security erase failure. */
 544                 if (request->op == TO_DSE)
 545                         return tape_34xx_erp_failed(request, -EIO);
 546                 /* Data security erase failure, but no such command issued. */
 547                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 548         case 0x2e:
 549                 /*
 550                  * Not capable. This indicates either that the drive fails
 551                  * reading the format id mark or that that format specified
 552                  * is not supported by the drive.
 553                  */
 554                 dev_warn (&device->cdev->dev, "The tape unit cannot process "
 555                         "the tape format\n");
 556                 return tape_34xx_erp_failed(request, -EMEDIUMTYPE);
 557         case 0x30:
 558                 /* The medium is write protected. */
 559                 dev_warn (&device->cdev->dev, "The tape medium is write-"
 560                         "protected\n");
 561                 return tape_34xx_erp_failed(request, -EACCES);
 562         case 0x32:
 563                 // Tension loss. We cannot recover this, it's an I/O error.
 564                 dev_warn (&device->cdev->dev, "The tape does not have the "
 565                         "required tape tension\n");
 566                 return tape_34xx_erp_failed(request, -EIO);
 567         case 0x33:
 568                 /*
 569                  * Load Failure. The cartridge was not inserted correctly or
 570                  * the tape is not threaded correctly.
 571                  */
 572                 dev_warn (&device->cdev->dev, "The tape unit failed to load"
 573                         " the cartridge\n");
 574                 tape_34xx_delete_sbid_from(device, 0);
 575                 return tape_34xx_erp_failed(request, -EIO);
 576         case 0x34:
 577                 /*
 578                  * Unload failure. The drive cannot maintain tape tension
 579                  * and control tape movement during an unload operation.
 580                  */
 581                 dev_warn (&device->cdev->dev, "Automatic unloading of the tape"
 582                         " cartridge failed\n");
 583                 if (request->op == TO_RUN)
 584                         return tape_34xx_erp_failed(request, -EIO);
 585                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 586         case 0x35:
 587                 /*
 588                  * Drive equipment check. One of the following:
 589                  * - cu cannot recover from a drive detected error
 590                  * - a check code message is shown on drive display
 591                  * - the cartridge loader does not respond correctly
 592                  * - a failure occurs during an index, load, or unload cycle
 593                  */
 594                 dev_warn (&device->cdev->dev, "An equipment check has occurred"
 595                         " on the tape unit\n");
 596                 return tape_34xx_erp_failed(request, -EIO);
 597         case 0x36:
 598                 if (device->cdev->id.driver_info == tape_3490)
 599                         /* End of data. */
 600                         return tape_34xx_erp_failed(request, -EIO);
 601                 /* This erpa is reserved for 3480 */
 602                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 603         case 0x37:
 604                 /*
 605                  * Tape length error. The tape is shorter than reported in
 606                  * the beginning-of-tape data.
 607                  */
 608                 dev_warn (&device->cdev->dev, "The tape information states an"
 609                         " incorrect length\n");
 610                 return tape_34xx_erp_failed(request, -EIO);
 611         case 0x38:
 612                 /*
 613                  * Physical end of tape. A read/write operation reached
 614                  * the physical end of tape.
 615                  */
 616                 if (request->op==TO_WRI ||
 617                     request->op==TO_DSE ||
 618                     request->op==TO_WTM)
 619                         return tape_34xx_erp_failed(request, -ENOSPC);
 620                 return tape_34xx_erp_failed(request, -EIO);
 621         case 0x39:
 622                 /* Backward at Beginning of tape. */
 623                 return tape_34xx_erp_failed(request, -EIO);
 624         case 0x3a:
 625                 /* Drive switched to not ready. */
 626                 dev_warn (&device->cdev->dev, "The tape unit is not ready\n");
 627                 return tape_34xx_erp_failed(request, -EIO);
 628         case 0x3b:
 629                 /* Manual rewind or unload. This causes an I/O error. */
 630                 dev_warn (&device->cdev->dev, "The tape medium has been "
 631                         "rewound or unloaded manually\n");
 632                 tape_34xx_delete_sbid_from(device, 0);
 633                 return tape_34xx_erp_failed(request, -EIO);
 634         case 0x42:
 635                 /*
 636                  * Degraded mode. A condition that can cause degraded
 637                  * performance is detected.
 638                  */
 639                 dev_warn (&device->cdev->dev, "The tape subsystem is running "
 640                         "in degraded mode\n");
 641                 return tape_34xx_erp_retry(request);
 642         case 0x43:
 643                 /* Drive not ready. */
 644                 tape_34xx_delete_sbid_from(device, 0);
 645                 tape_med_state_set(device, MS_UNLOADED);
 646                 /* Some commands commands are successful even in this case */
 647                 if (sense[1] & SENSE_DRIVE_ONLINE) {
 648                         switch(request->op) {
 649                                 case TO_ASSIGN:
 650                                 case TO_UNASSIGN:
 651                                 case TO_DIS:
 652                                 case TO_NOP:
 653                                         return tape_34xx_done(request);
 654                                         break;
 655                                 default:
 656                                         break;
 657                         }
 658                 }
 659                 return tape_34xx_erp_failed(request, -ENOMEDIUM);
 660         case 0x44:
 661                 /* Locate Block unsuccessful. */
 662                 if (request->op != TO_BLOCK && request->op != TO_LBL)
 663                         /* No locate block was issued. */
 664                         return tape_34xx_erp_bug(device, request,
 665                                                  irb, sense[3]);
 666                 return tape_34xx_erp_failed(request, -EIO);
 667         case 0x45:
 668                 /* The drive is assigned to a different channel path. */
 669                 dev_warn (&device->cdev->dev, "The tape unit is already "
 670                         "assigned\n");
 671                 return tape_34xx_erp_failed(request, -EIO);
 672         case 0x46:
 673                 /*
 674                  * Drive not on-line. Drive may be switched offline,
 675                  * the power supply may be switched off or
 676                  * the drive address may not be set correctly.
 677                  */
 678                 dev_warn (&device->cdev->dev, "The tape unit is not online\n");
 679                 return tape_34xx_erp_failed(request, -EIO);
 680         case 0x47:
 681                 /* Volume fenced. CU reports volume integrity is lost. */
 682                 dev_warn (&device->cdev->dev, "The control unit has fenced "
 683                         "access to the tape volume\n");
 684                 tape_34xx_delete_sbid_from(device, 0);
 685                 return tape_34xx_erp_failed(request, -EIO);
 686         case 0x48:
 687                 /* Log sense data and retry request. */
 688                 return tape_34xx_erp_retry(request);
 689         case 0x49:
 690                 /* Bus out check. A parity check error on the bus was found. */
 691                 dev_warn (&device->cdev->dev, "A parity error occurred on the "
 692                         "tape bus\n");
 693                 return tape_34xx_erp_failed(request, -EIO);
 694         case 0x4a:
 695                 /* Control unit erp failed. */
 696                 dev_warn (&device->cdev->dev, "I/O error recovery failed on "
 697                         "the tape control unit\n");
 698                 return tape_34xx_erp_failed(request, -EIO);
 699         case 0x4b:
 700                 /*
 701                  * CU and drive incompatible. The drive requests micro-program
 702                  * patches, which are not available on the CU.
 703                  */
 704                 dev_warn (&device->cdev->dev, "The tape unit requires a "
 705                         "firmware update\n");
 706                 return tape_34xx_erp_failed(request, -EIO);
 707         case 0x4c:
 708                 /*
 709                  * Recovered Check-One failure. Cu develops a hardware error,
 710                  * but is able to recover.
 711                  */
 712                 return tape_34xx_erp_retry(request);
 713         case 0x4d:
 714                 if (device->cdev->id.driver_info == tape_3490)
 715                         /*
 716                          * Resetting event received. Since the driver does
 717                          * not support resetting event recovery (which has to
 718                          * be handled by the I/O Layer), retry our command.
 719                          */
 720                         return tape_34xx_erp_retry(request);
 721                 /* This erpa is reserved for 3480. */
 722                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 723         case 0x4e:
 724                 if (device->cdev->id.driver_info == tape_3490) {
 725                         /*
 726                          * Maximum block size exceeded. This indicates, that
 727                          * the block to be written is larger than allowed for
 728                          * buffered mode.
 729                          */
 730                         dev_warn (&device->cdev->dev, "The maximum block size"
 731                                 " for buffered mode is exceeded\n");
 732                         return tape_34xx_erp_failed(request, -ENOBUFS);
 733                 }
 734                 /* This erpa is reserved for 3480. */
 735                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 736         case 0x50:
 737                 /*
 738                  * Read buffered log (Overflow). CU is running in extended
 739                  * buffered log mode, and a counter overflows. This should
 740                  * never happen, since we're never running in extended
 741                  * buffered log mode.
 742                  */
 743                 return tape_34xx_erp_retry(request);
 744         case 0x51:
 745                 /*
 746                  * Read buffered log (EOV). EOF processing occurs while the
 747                  * CU is in extended buffered log mode. This should never
 748                  * happen, since we're never running in extended buffered
 749                  * log mode.
 750                  */
 751                 return tape_34xx_erp_retry(request);
 752         case 0x52:
 753                 /* End of Volume complete. Rewind unload completed ok. */
 754                 if (request->op == TO_RUN) {
 755                         tape_med_state_set(device, MS_UNLOADED);
 756                         tape_34xx_delete_sbid_from(device, 0);
 757                         return tape_34xx_erp_succeeded(request);
 758                 }
 759                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 760         case 0x53:
 761                 /* Global command intercept. */
 762                 return tape_34xx_erp_retry(request);
 763         case 0x54:
 764                 /* Channel interface recovery (temporary). */
 765                 return tape_34xx_erp_retry(request);
 766         case 0x55:
 767                 /* Channel interface recovery (permanent). */
 768                 dev_warn (&device->cdev->dev, "A channel interface error cannot be"
 769                         " recovered\n");
 770                 return tape_34xx_erp_failed(request, -EIO);
 771         case 0x56:
 772                 /* Channel protocol error. */
 773                 dev_warn (&device->cdev->dev, "A channel protocol error "
 774                         "occurred\n");
 775                 return tape_34xx_erp_failed(request, -EIO);
 776         case 0x57:
 777                 /*
 778                  * 3480: Attention intercept.
 779                  * 3490: Global status intercept.
 780                  */
 781                 return tape_34xx_erp_retry(request);
 782         case 0x5a:
 783                 /*
 784                  * Tape length incompatible. The tape inserted is too long,
 785                  * which could cause damage to the tape or the drive.
 786                  */
 787                 dev_warn (&device->cdev->dev, "The tape unit does not support "
 788                         "the tape length\n");
 789                 return tape_34xx_erp_failed(request, -EIO);
 790         case 0x5b:
 791                 /* Format 3480 XF incompatible */
 792                 if (sense[1] & SENSE_BEGINNING_OF_TAPE)
 793                         /* The tape will get overwritten. */
 794                         return tape_34xx_erp_retry(request);
 795                 dev_warn (&device->cdev->dev, "The tape unit does not support"
 796                         " format 3480 XF\n");
 797                 return tape_34xx_erp_failed(request, -EIO);
 798         case 0x5c:
 799                 /* Format 3480-2 XF incompatible */
 800                 dev_warn (&device->cdev->dev, "The tape unit does not support tape "
 801                         "format 3480-2 XF\n");
 802                 return tape_34xx_erp_failed(request, -EIO);
 803         case 0x5d:
 804                 /* Tape length violation. */
 805                 dev_warn (&device->cdev->dev, "The tape unit does not support"
 806                         " the current tape length\n");
 807                 return tape_34xx_erp_failed(request, -EMEDIUMTYPE);
 808         case 0x5e:
 809                 /* Compaction algorithm incompatible. */
 810                 dev_warn (&device->cdev->dev, "The tape unit does not support"
 811                         " the compaction algorithm\n");
 812                 return tape_34xx_erp_failed(request, -EMEDIUMTYPE);
 813
 814                 /* The following erpas should have been covered earlier. */
 815         case 0x23: /* Read data check. */
 816         case 0x25: /* Write data check. */
 817         case 0x26: /* Data check (read opposite). */
 818         case 0x28: /* Write id mark check. */
 819         case 0x31: /* Tape void. */
 820         case 0x40: /* Overrun error. */
 821         case 0x41: /* Record sequence error. */
 822                 /* All other erpas are reserved for future use. */
 823         default:
 824                 return tape_34xx_erp_bug(device, request, irb, sense[3]);
 825         }
 826 }
 827
 828 /*
 829  * 3480/3490 interrupt handler
 830  */
 831 static int
 832 tape_34xx_irq(struct tape_device *device, struct tape_request *request,
 833               struct irb *irb)
 834 {
 835         if (request == NULL)
 836                 return tape_34xx_unsolicited_irq(device, irb);
 837
 838         if ((irb->scsw.cmd.dstat & DEV_STAT_UNIT_EXCEP) &&
 839             (irb->scsw.cmd.dstat & DEV_STAT_DEV_END) &&
 840             (request->op == TO_WRI)) {
 841                 /* Write at end of volume */
 842                 return tape_34xx_erp_failed(request, -ENOSPC);
 843         }
 844
 845         if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK)
 846                 return tape_34xx_unit_check(device, request, irb);
 847
 848         if (irb->scsw.cmd.dstat & DEV_STAT_DEV_END) {
 849                 /*
 850                  * A unit exception occurs on skipping over a tapemark block.
 851                  */
 852                 if (irb->scsw.cmd.dstat & DEV_STAT_UNIT_EXCEP) {
 853                         if (request->op == TO_BSB || request->op == TO_FSB)
 854                                 request->rescnt++;
 855                         else
 856                                 DBF_EVENT(5, "Unit Exception!\n");
 857                 }
 858                 return tape_34xx_done(request);
 859         }
 860
 861         DBF_EVENT(6, "xunknownirq\n");
 862         tape_dump_sense_dbf(device, request, irb);
 863         return TAPE_IO_STOP;
 864 }
 865
 866 /*
 867  * ioctl_overload
 868  */
 869 static int
 870 tape_34xx_ioctl(struct tape_device *device, unsigned int cmd, unsigned long arg)
 871 {
 872         if (cmd == TAPE390_DISPLAY) {
 873                 struct display_struct disp;
 874
 875                 if (copy_from_user(&disp, (char __user *) arg, sizeof(disp)) != 0)
 876                         return -EFAULT;
 877
 878                 return tape_std_display(device, &disp);
 879         } else
 880                 return -EINVAL;
 881 }
 882
 883 static inline void
 884 tape_34xx_append_new_sbid(struct tape_34xx_block_id bid, struct list_head *l)
 885 {
 886         struct tape_34xx_sbid * new_sbid;
 887
 888         new_sbid = kmalloc(sizeof(*new_sbid), GFP_ATOMIC);
 889         if (!new_sbid)
 890                 return;
 891
 892         new_sbid->bid = bid;
 893         list_add(&new_sbid->list, l);
 894 }
 895
 896 /*
 897  * Build up the search block ID list. The block ID consists of a logical
 898  * block number and a hardware specific part. The hardware specific part
 899  * helps the tape drive to speed up searching for a specific block.
 900  */
 901 static void
 902 tape_34xx_add_sbid(struct tape_device *device, struct tape_34xx_block_id bid)
 903 {
 904         struct list_head *      sbid_list;
 905         struct tape_34xx_sbid * sbid;
 906         struct list_head *      l;
 907
 908         /*
 909          * immediately return if there is no list at all or the block to add
 910          * is located in segment 1 of wrap 0 because this position is used
 911          * if no hardware position data is supplied.
 912          */
 913         sbid_list = (struct list_head *) device->discdata;
 914         if (!sbid_list || (bid.segment < 2 && bid.wrap == 0))
 915                 return;
 916
 917         /*
 918          * Search the position where to insert the new entry. Hardware
 919          * acceleration uses only the segment and wrap number. So we
 920          * need only one entry for a specific wrap/segment combination.
 921          * If there is a block with a lower number but the same hard-
 922          * ware position data we just update the block number in the
 923          * existing entry.
 924          */
 925         list_for_each(l, sbid_list) {
 926                 sbid = list_entry(l, struct tape_34xx_sbid, list);
 927
 928                 if (
 929                         (sbid->bid.segment == bid.segment) &&
 930                         (sbid->bid.wrap    == bid.wrap)
 931                 ) {
 932                         if (bid.block < sbid->bid.block)
 933                                 sbid->bid = bid;
 934                         else return;
 935                         break;
 936                 }
 937
 938                 /* Sort in according to logical block number. */
 939                 if (bid.block < sbid->bid.block) {
 940                         tape_34xx_append_new_sbid(bid, l->prev);
 941                         break;
 942                 }
 943         }
 944         /* List empty or new block bigger than last entry. */
 945         if (l == sbid_list)
 946                 tape_34xx_append_new_sbid(bid, l->prev);
 947
 948         DBF_LH(4, "Current list is:\n");
 949         list_for_each(l, sbid_list) {
 950                 sbid = list_entry(l, struct tape_34xx_sbid, list);
 951                 DBF_LH(4, "%d:%03d@%05d\n",
 952                         sbid->bid.wrap,
 953                         sbid->bid.segment,
 954                         sbid->bid.block
 955                 );
 956         }
 957 }
 958
 959 /*
 960  * Delete all entries from the search block ID list that belong to tape blocks
 961  * equal or higher than the given number.
 962  */
 963 static void
 964 tape_34xx_delete_sbid_from(struct tape_device *device, int from)
 965 {
 966         struct list_head *      sbid_list;
 967         struct tape_34xx_sbid * sbid;
 968         struct list_head *      l;
 969         struct list_head *      n;
 970
 971         sbid_list = (struct list_head *) device->discdata;
 972         if (!sbid_list)
 973                 return;
 974
 975         list_for_each_safe(l, n, sbid_list) {
 976                 sbid = list_entry(l, struct tape_34xx_sbid, list);
 977                 if (sbid->bid.block >= from) {
 978                         DBF_LH(4, "Delete sbid %d:%03d@%05d\n",
 979                                 sbid->bid.wrap,
 980                                 sbid->bid.segment,
 981                                 sbid->bid.block
 982                         );
 983                         list_del(l);
 984                         kfree(sbid);
 985                 }
 986         }
 987 }
 988
 989 /*
 990  * Merge hardware position data into a block id.
 991  */
 992 static void
 993 tape_34xx_merge_sbid(
 994         struct tape_device *            device,
 995         struct tape_34xx_block_id *     bid
 996 ) {
 997         struct tape_34xx_sbid * sbid;
 998         struct tape_34xx_sbid * sbid_to_use;
 999         struct list_head *      sbid_list;
1000         struct list_head *      l;
1001
1002         sbid_list = (struct list_head *) device->discdata;
1003         bid->wrap    = 0;
1004         bid->segment = 1;
1005
1006         if (!sbid_list || list_empty(sbid_list))
1007                 return;
1008
1009         sbid_to_use = NULL;
1010         list_for_each(l, sbid_list) {
1011                 sbid = list_entry(l, struct tape_34xx_sbid, list);
1012
1013                 if (sbid->bid.block >= bid->block)
1014                         break;
1015                 sbid_to_use = sbid;
1016         }
1017         if (sbid_to_use) {
1018                 bid->wrap    = sbid_to_use->bid.wrap;
1019                 bid->segment = sbid_to_use->bid.segment;
1020                 DBF_LH(4, "Use %d:%03d@%05d for %05d\n",
1021                         sbid_to_use->bid.wrap,
1022                         sbid_to_use->bid.segment,
1023                         sbid_to_use->bid.block,
1024                         bid->block
1025                 );
1026         }
1027 }
1028
1029 static int
1030 tape_34xx_setup_device(struct tape_device * device)
1031 {
1032         int                     rc;
1033         struct list_head *      discdata;
1034
1035         DBF_EVENT(6, "34xx device setup\n");
1036         if ((rc = tape_std_assign(device)) == 0) {
1037                 if ((rc = tape_34xx_medium_sense(device)) != 0) {
1038                         DBF_LH(3, "34xx medium sense returned %d\n", rc);
1039                 }
1040         }
1041         discdata = kmalloc(sizeof(struct list_head), GFP_KERNEL);
1042         if (discdata) {
1043                         INIT_LIST_HEAD(discdata);
1044                         device->discdata = discdata;
1045         }
1046
1047         return rc;
1048 }
1049
1050 static void
1051 tape_34xx_cleanup_device(struct tape_device *device)
1052 {
1053         tape_std_unassign(device);
1054
1055         if (device->discdata) {
1056                 tape_34xx_delete_sbid_from(device, 0);
1057                 kfree(device->discdata);
1058                 device->discdata = NULL;
1059         }
1060 }
1061
1062
1063 /*
1064  * MTTELL: Tell block. Return the number of block relative to current file.
1065  */
1066 static int
1067 tape_34xx_mttell(struct tape_device *device, int mt_count)
1068 {
1069         struct {
1070                 struct tape_34xx_block_id       cbid;
1071                 struct tape_34xx_block_id       dbid;
1072         } __attribute__ ((packed)) block_id;
1073         int rc;
1074
1075         rc = tape_std_read_block_id(device, (__u64 *) &block_id);
1076         if (rc)
1077                 return rc;
1078
1079         tape_34xx_add_sbid(device, block_id.cbid);
1080         return block_id.cbid.block;
1081 }
1082
1083 /*
1084  * MTSEEK: seek to the specified block.
1085  */
1086 static int
1087 tape_34xx_mtseek(struct tape_device *device, int mt_count)
1088 {
1089         struct tape_request *request;
1090         struct tape_34xx_block_id *     bid;
1091
1092         if (mt_count > 0x3fffff) {
1093                 DBF_EXCEPTION(6, "xsee parm\n");
1094                 return -EINVAL;
1095         }
1096         request = tape_alloc_request(3, 4);
1097         if (IS_ERR(request))
1098                 return PTR_ERR(request);
1099
1100         /* setup ccws */
1101         request->op = TO_LBL;
1102         bid         = (struct tape_34xx_block_id *) request->cpdata;
1103         bid->format = (*device->modeset_byte & 0x08) ?
1104                         TAPE34XX_FMT_3480_XF : TAPE34XX_FMT_3480;
1105         bid->block  = mt_count;
1106         tape_34xx_merge_sbid(device, bid);
1107
1108         tape_ccw_cc(request->cpaddr, MODE_SET_DB, 1, device->modeset_byte);
1109         tape_ccw_cc(request->cpaddr + 1, LOCATE, 4, request->cpdata);
1110         tape_ccw_end(request->cpaddr + 2, NOP, 0, NULL);
1111
1112         /* execute it */
1113         return tape_do_io_free(device, request);
1114 }
1115
1116 /*
1117  * List of 3480/3490 magnetic tape commands.
1118  */
1119 static tape_mtop_fn tape_34xx_mtop[TAPE_NR_MTOPS] = {
1120         [MTRESET]        = tape_std_mtreset,
1121         [MTFSF]          = tape_std_mtfsf,
1122         [MTBSF]          = tape_std_mtbsf,
1123         [MTFSR]          = tape_std_mtfsr,
1124         [MTBSR]          = tape_std_mtbsr,
1125         [MTWEOF]         = tape_std_mtweof,
1126         [MTREW]          = tape_std_mtrew,
1127         [MTOFFL]         = tape_std_mtoffl,
1128         [MTNOP]          = tape_std_mtnop,
1129         [MTRETEN]        = tape_std_mtreten,
1130         [MTBSFM]         = tape_std_mtbsfm,
1131         [MTFSFM]         = tape_std_mtfsfm,
1132         [MTEOM]          = tape_std_mteom,
1133         [MTERASE]        = tape_std_mterase,
1134         [MTRAS1]         = NULL,
1135         [MTRAS2]         = NULL,
1136         [MTRAS3]         = NULL,
1137         [MTSETBLK]       = tape_std_mtsetblk,
1138         [MTSETDENSITY]   = NULL,
1139         [MTSEEK]         = tape_34xx_mtseek,
1140         [MTTELL]         = tape_34xx_mttell,
1141         [MTSETDRVBUFFER] = NULL,
1142         [MTFSS]          = NULL,
1143         [MTBSS]          = NULL,
1144         [MTWSM]          = NULL,
1145         [MTLOCK]         = NULL,
1146         [MTUNLOCK]       = NULL,
1147         [MTLOAD]         = tape_std_mtload,
1148         [MTUNLOAD]       = tape_std_mtunload,
1149         [MTCOMPRESSION]  = tape_std_mtcompression,
1150         [MTSETPART]      = NULL,
1151         [MTMKPART]       = NULL
1152 };
1153
1154 /*
1155  * Tape discipline structure for 3480 and 3490.
1156  */
1157 static struct tape_discipline tape_discipline_34xx = {
1158         .owner = THIS_MODULE,
1159         .setup_device = tape_34xx_setup_device,
1160         .cleanup_device = tape_34xx_cleanup_device,
1161         .process_eov = tape_std_process_eov,
1162         .irq = tape_34xx_irq,
1163         .read_block = tape_std_read_block,
1164         .write_block = tape_std_write_block,
1165         .ioctl_fn = tape_34xx_ioctl,
1166         .mtop_array = tape_34xx_mtop
1167 };
1168
1169 static struct ccw_device_id tape_34xx_ids[] = {
1170         { CCW_DEVICE_DEVTYPE(0x3480, 0, 0x3480, 0), .driver_info = tape_3480},
1171         { CCW_DEVICE_DEVTYPE(0x3490, 0, 0x3490, 0), .driver_info = tape_3490},
1172         { /* end of list */ },
1173 };
1174
1175 static int
1176 tape_34xx_online(struct ccw_device *cdev)
1177 {
1178         return tape_generic_online(
1179                 dev_get_drvdata(&cdev->dev),
1180                 &tape_discipline_34xx
1181         );
1182 }
1183
1184 static struct ccw_driver tape_34xx_driver = {
1185         .driver = {
1186                 .name = "tape_34xx",
1187                 .owner = THIS_MODULE,
1188         },
1189         .ids = tape_34xx_ids,
1190         .probe = tape_generic_probe,
1191         .remove = tape_generic_remove,
1192         .set_online = tape_34xx_online,
1193         .set_offline = tape_generic_offline,
1194         .freeze = tape_generic_pm_suspend,
1195         .int_class = IRQIO_TAP,
1196 };
1197
1198 static int
1199 tape_34xx_init (void)
1200 {
1201         int rc;
1202
1203         TAPE_DBF_AREA = debug_register ( "tape_34xx", 2, 2, 4*sizeof(long));
1204         debug_register_view(TAPE_DBF_AREA, &debug_sprintf_view);
1205 #ifdef DBF_LIKE_HELL
1206         debug_set_level(TAPE_DBF_AREA, 6);
1207 #endif
1208
1209         DBF_EVENT(3, "34xx init\n");
1210         /* Register driver for 3480/3490 tapes. */
1211         rc = ccw_driver_register(&tape_34xx_driver);
1212         if (rc)
1213                 DBF_EVENT(3, "34xx init failed\n");
1214         else
1215                 DBF_EVENT(3, "34xx registered\n");
1216         return rc;
1217 }
1218
1219 static void
1220 tape_34xx_exit(void)
1221 {
1222         ccw_driver_unregister(&tape_34xx_driver);
1223
1224         debug_unregister(TAPE_DBF_AREA);
1225 }
1226
1227 MODULE_DEVICE_TABLE(ccw, tape_34xx_ids);
1228 MODULE_AUTHOR("(C) 2001-2002 IBM Deutschland Entwicklung GmbH");
1229 MODULE_DESCRIPTION("Linux on zSeries channel attached 3480 tape device driver");
1230 MODULE_LICENSE("GPL");
1231
1232 module_init(tape_34xx_init);
1233 module_exit(tape_34xx_exit);