drivers/s390/block/dasd_diag.c

   1 /*
   2  * File...........: linux/drivers/s390/block/dasd_diag.c
   3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   4  * Based on.......: linux/drivers/s390/block/mdisk.c
   5  * ...............: by Hartmunt Penner <hpenner@de.ibm.com>
   6  * Bugreports.to..: <Linux390@de.ibm.com>
   7  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
   8  *
   9  */
  10
  11 #include <linux/stddef.h>
  12 #include <linux/kernel.h>
  13 #include <linux/slab.h>
  14 #include <linux/hdreg.h>
  15 #include <linux/bio.h>
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/jiffies.h>
  19
  20 #include <asm/dasd.h>
  21 #include <asm/debug.h>
  22 #include <asm/ebcdic.h>
  23 #include <asm/io.h>
  24 #include <asm/s390_ext.h>
  25 #include <asm/todclk.h>
  26 #include <asm/vtoc.h>
  27
  28 #include "dasd_int.h"
  29 #include "dasd_diag.h"
  30
  31 #define PRINTK_HEADER "dasd(diag):"
  32
  33 MODULE_LICENSE("GPL");
  34
  35 /* The maximum number of blocks per request (max_blocks) is dependent on the
  36  * amount of storage that is available in the static I/O buffer for each
  37  * device. Currently each device gets 2 pages. We want to fit two requests
  38  * into the available memory so that we can immediately start the next if one
  39  * finishes. */
  40 #define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \
  41                            sizeof(struct dasd_diag_req)) / \
  42                            sizeof(struct dasd_diag_bio)) / 2)
  43 #define DIAG_MAX_RETRIES        32
  44 #define DIAG_TIMEOUT            50 * HZ
  45
  46 static struct dasd_discipline dasd_diag_discipline;
  47
  48 struct dasd_diag_private {
  49         struct dasd_diag_characteristics rdc_data;
  50         struct dasd_diag_rw_io iob;
  51         struct dasd_diag_init_io iib;
  52         blocknum_t pt_block;
  53 };
  54
  55 struct dasd_diag_req {
  56         unsigned int block_count;
  57         struct dasd_diag_bio bio[0];
  58 };
  59
  60 static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */
  61
  62 /* Perform DIAG250 call with block I/O parameter list iob (input and output)
  63  * and function code cmd.
  64  * In case of an exception return 3. Otherwise return result of bitwise OR of
  65  * resulting condition code and DIAG return code. */
  66 static inline int dia250(void *iob, int cmd)
  67 {
  68         register unsigned long reg2 asm ("2") = (unsigned long) iob;
  69         typedef union {
  70                 struct dasd_diag_init_io init_io;
  71                 struct dasd_diag_rw_io rw_io;
  72         } addr_type;
  73         int rc;
  74
  75         rc = 3;
  76         asm volatile(
  77                 "       diag    2,%2,0x250\n"
  78                 "0:     ipm     %0\n"
  79                 "       srl     %0,28\n"
  80                 "       or      %0,3\n"
  81                 "1:\n"
  82                 EX_TABLE(0b,1b)
  83                 : "+d" (rc), "=m" (*(addr_type *) iob)
  84                 : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob)
  85                 : "3", "cc");
  86         return rc;
  87 }
  88
  89 /* Initialize block I/O to DIAG device using the specified blocksize and
  90  * block offset. On success, return zero and set end_block to contain the
  91  * number of blocks on the device minus the specified offset. Return non-zero
  92  * otherwise. */
  93 static inline int
  94 mdsk_init_io(struct dasd_device *device, unsigned int blocksize,
  95              blocknum_t offset, blocknum_t *end_block)
  96 {
  97         struct dasd_diag_private *private;
  98         struct dasd_diag_init_io *iib;
  99         int rc;
 100
 101         private = (struct dasd_diag_private *) device->private;
 102         iib = &private->iib;
 103         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 104
 105         iib->dev_nr = _ccw_device_get_device_number(device->cdev);
 106         iib->block_size = blocksize;
 107         iib->offset = offset;
 108         iib->flaga = DASD_DIAG_FLAGA_DEFAULT;
 109
 110         rc = dia250(iib, INIT_BIO);
 111
 112         if ((rc & 3) == 0 && end_block)
 113                 *end_block = iib->end_block;
 114
 115         return rc;
 116 }
 117
 118 /* Remove block I/O environment for device. Return zero on success, non-zero
 119  * otherwise. */
 120 static inline int
 121 mdsk_term_io(struct dasd_device * device)
 122 {
 123         struct dasd_diag_private *private;
 124         struct dasd_diag_init_io *iib;
 125         int rc;
 126
 127         private = (struct dasd_diag_private *) device->private;
 128         iib = &private->iib;
 129         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 130         iib->dev_nr = _ccw_device_get_device_number(device->cdev);
 131         rc = dia250(iib, TERM_BIO);
 132         return rc;
 133 }
 134
 135 /* Error recovery for failed DIAG requests - try to reestablish the DIAG
 136  * environment. */
 137 static void
 138 dasd_diag_erp(struct dasd_device *device)
 139 {
 140         int rc;
 141
 142         mdsk_term_io(device);
 143         rc = mdsk_init_io(device, device->bp_block, 0, NULL);
 144         if (rc)
 145                 DEV_MESSAGE(KERN_WARNING, device, "DIAG ERP unsuccessful, "
 146                             "rc=%d", rc);
 147 }
 148
 149 /* Start a given request at the device. Return zero on success, non-zero
 150  * otherwise. */
 151 static int
 152 dasd_start_diag(struct dasd_ccw_req * cqr)
 153 {
 154         struct dasd_device *device;
 155         struct dasd_diag_private *private;
 156         struct dasd_diag_req *dreq;
 157         int rc;
 158
 159         device = cqr->device;
 160         if (cqr->retries < 0) {
 161                 DEV_MESSAGE(KERN_WARNING, device, "DIAG start_IO: request %p "
 162                             "- no retry left)", cqr);
 163                 cqr->status = DASD_CQR_FAILED;
 164                 return -EIO;
 165         }
 166         private = (struct dasd_diag_private *) device->private;
 167         dreq = (struct dasd_diag_req *) cqr->data;
 168
 169         private->iob.dev_nr = _ccw_device_get_device_number(device->cdev);
 170         private->iob.key = 0;
 171         private->iob.flags = DASD_DIAG_RWFLAG_ASYNC;
 172         private->iob.block_count = dreq->block_count;
 173         private->iob.interrupt_params = (addr_t) cqr;
 174         private->iob.bio_list = dreq->bio;
 175         private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 176
 177         cqr->startclk = get_clock();
 178         cqr->starttime = jiffies;
 179         cqr->retries--;
 180
 181         rc = dia250(&private->iob, RW_BIO);
 182         switch (rc) {
 183         case 0: /* Synchronous I/O finished successfully */
 184                 cqr->stopclk = get_clock();
 185                 cqr->status = DASD_CQR_DONE;
 186                 /* Indicate to calling function that only a dasd_schedule_bh()
 187                    and no timer is needed */
 188                 rc = -EACCES;
 189                 break;
 190         case 8: /* Asynchronous I/O was started */
 191                 cqr->status = DASD_CQR_IN_IO;
 192                 rc = 0;
 193                 break;
 194         default: /* Error condition */
 195                 cqr->status = DASD_CQR_QUEUED;
 196                 DEV_MESSAGE(KERN_WARNING, device, "dia250 returned rc=%d", rc);
 197                 dasd_diag_erp(device);
 198                 rc = -EIO;
 199                 break;
 200         }
 201         return rc;
 202 }
 203
 204 /* Terminate given request at the device. */
 205 static int
 206 dasd_diag_term_IO(struct dasd_ccw_req * cqr)
 207 {
 208         struct dasd_device *device;
 209
 210         device = cqr->device;
 211         mdsk_term_io(device);
 212         mdsk_init_io(device, device->bp_block, 0, NULL);
 213         cqr->status = DASD_CQR_CLEAR;
 214         cqr->stopclk = get_clock();
 215         dasd_schedule_bh(device);
 216         return 0;
 217 }
 218
 219 /* Handle external interruption. */
 220 static void
 221 dasd_ext_handler(__u16 code)
 222 {
 223         struct dasd_ccw_req *cqr, *next;
 224         struct dasd_device *device;
 225         unsigned long long expires;
 226         unsigned long flags;
 227         u8 int_code, status;
 228         addr_t ip;
 229         int rc;
 230
 231         int_code = *((u8 *) DASD_DIAG_LC_INT_CODE);
 232         status = *((u8 *) DASD_DIAG_LC_INT_STATUS);
 233         switch (int_code) {
 234         case DASD_DIAG_CODE_31BIT:
 235                 ip = (addr_t) *((u32 *) DASD_DIAG_LC_INT_PARM_31BIT);
 236                 break;
 237         case DASD_DIAG_CODE_64BIT:
 238                 ip = (addr_t) *((u64 *) DASD_DIAG_LC_INT_PARM_64BIT);
 239                 break;
 240         default:
 241                 return;
 242         }
 243         if (!ip) {              /* no intparm: unsolicited interrupt */
 244                 MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt");
 245                 return;
 246         }
 247         cqr = (struct dasd_ccw_req *) ip;
 248         device = (struct dasd_device *) cqr->device;
 249         if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 250                 DEV_MESSAGE(KERN_WARNING, device,
 251                             " magic number of dasd_ccw_req 0x%08X doesn't"
 252                             " match discipline 0x%08X",
 253                             cqr->magic, *(int *) (&device->discipline->name));
 254                 return;
 255         }
 256
 257         /* get irq lock to modify request queue */
 258         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 259
 260         /* Check for a pending clear operation */
 261         if (cqr->status == DASD_CQR_CLEAR) {
 262                 cqr->status = DASD_CQR_QUEUED;
 263                 dasd_clear_timer(device);
 264                 dasd_schedule_bh(device);
 265                 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 266                 return;
 267         }
 268
 269         cqr->stopclk = get_clock();
 270
 271         expires = 0;
 272         if (status == 0) {
 273                 cqr->status = DASD_CQR_DONE;
 274                 /* Start first request on queue if possible -> fast_io. */
 275                 if (!list_empty(&device->ccw_queue)) {
 276                         next = list_entry(device->ccw_queue.next,
 277                                           struct dasd_ccw_req, list);
 278                         if (next->status == DASD_CQR_QUEUED) {
 279                                 rc = dasd_start_diag(next);
 280                                 if (rc == 0)
 281                                         expires = next->expires;
 282                                 else if (rc != -EACCES)
 283                                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 284                                                     "Interrupt fastpath "
 285                                                     "failed!");
 286                         }
 287                 }
 288         } else {
 289                 cqr->status = DASD_CQR_QUEUED;
 290                 DEV_MESSAGE(KERN_WARNING, device, "interrupt status for "
 291                             "request %p was %d (%d retries left)", cqr, status,
 292                             cqr->retries);
 293                 dasd_diag_erp(device);
 294         }
 295
 296         if (expires != 0)
 297                 dasd_set_timer(device, expires);
 298         else
 299                 dasd_clear_timer(device);
 300         dasd_schedule_bh(device);
 301
 302         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 303 }
 304
 305 /* Check whether device can be controlled by DIAG discipline. Return zero on
 306  * success, non-zero otherwise. */
 307 static int
 308 dasd_diag_check_device(struct dasd_device *device)
 309 {
 310         struct dasd_diag_private *private;
 311         struct dasd_diag_characteristics *rdc_data;
 312         struct dasd_diag_bio bio;
 313         struct vtoc_cms_label *label;
 314         blocknum_t end_block;
 315         unsigned int sb, bsize;
 316         int rc;
 317
 318         private = (struct dasd_diag_private *) device->private;
 319         if (private == NULL) {
 320                 private = kzalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
 321                 if (private == NULL) {
 322                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 323                                 "memory allocation failed for private data");
 324                         return -ENOMEM;
 325                 }
 326                 device->private = (void *) private;
 327         }
 328         /* Read Device Characteristics */
 329         rdc_data = (void *) &(private->rdc_data);
 330         rdc_data->dev_nr = _ccw_device_get_device_number(device->cdev);
 331         rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
 332
 333         rc = diag210((struct diag210 *) rdc_data);
 334         if (rc) {
 335                 DEV_MESSAGE(KERN_WARNING, device, "failed to retrieve device "
 336                             "information (rc=%d)", rc);
 337                 return -ENOTSUPP;
 338         }
 339
 340         /* Figure out position of label block */
 341         switch (private->rdc_data.vdev_class) {
 342         case DEV_CLASS_FBA:
 343                 private->pt_block = 1;
 344                 break;
 345         case DEV_CLASS_ECKD:
 346                 private->pt_block = 2;
 347                 break;
 348         default:
 349                 DEV_MESSAGE(KERN_WARNING, device, "unsupported device class "
 350                             "(class=%d)", private->rdc_data.vdev_class);
 351                 return -ENOTSUPP;
 352         }
 353
 354         DBF_DEV_EVENT(DBF_INFO, device,
 355                       "%04X: %04X on real %04X/%02X",
 356                       rdc_data->dev_nr,
 357                       rdc_data->vdev_type,
 358                       rdc_data->rdev_type, rdc_data->rdev_model);
 359
 360         /* terminate all outstanding operations */
 361         mdsk_term_io(device);
 362
 363         /* figure out blocksize of device */
 364         label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL);
 365         if (label == NULL)  {
 366                 DEV_MESSAGE(KERN_WARNING, device, "%s",
 367                             "No memory to allocate initialization request");
 368                 return -ENOMEM;
 369         }
 370         rc = 0;
 371         end_block = 0;
 372         /* try all sizes - needed for ECKD devices */
 373         for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
 374                 mdsk_init_io(device, bsize, 0, &end_block);
 375                 memset(&bio, 0, sizeof (struct dasd_diag_bio));
 376                 bio.type = MDSK_READ_REQ;
 377                 bio.block_number = private->pt_block + 1;
 378                 bio.buffer = label;
 379                 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
 380                 private->iob.dev_nr = rdc_data->dev_nr;
 381                 private->iob.key = 0;
 382                 private->iob.flags = 0; /* do synchronous io */
 383                 private->iob.block_count = 1;
 384                 private->iob.interrupt_params = 0;
 385                 private->iob.bio_list = &bio;
 386                 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 387                 rc = dia250(&private->iob, RW_BIO);
 388                 if (rc == 3) {
 389                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 390                                 "DIAG call failed");
 391                         rc = -EOPNOTSUPP;
 392                         goto out;
 393                 }
 394                 mdsk_term_io(device);
 395                 if (rc == 0)
 396                         break;
 397         }
 398         if (bsize > PAGE_SIZE) {
 399                 DEV_MESSAGE(KERN_WARNING, device, "device access failed "
 400                             "(rc=%d)", rc);
 401                 rc = -EIO;
 402                 goto out;
 403         }
 404         /* check for label block */
 405         if (memcmp(label->label_id, DASD_DIAG_CMS1,
 406                   sizeof(DASD_DIAG_CMS1)) == 0) {
 407                 /* get formatted blocksize from label block */
 408                 bsize = (unsigned int) label->block_size;
 409                 device->blocks = (unsigned long) label->block_count;
 410         } else
 411                 device->blocks = end_block;
 412         device->bp_block = bsize;
 413         device->s2b_shift = 0;  /* bits to shift 512 to get a block */
 414         for (sb = 512; sb < bsize; sb = sb << 1)
 415                 device->s2b_shift++;
 416         rc = mdsk_init_io(device, device->bp_block, 0, NULL);
 417         if (rc) {
 418                 DEV_MESSAGE(KERN_WARNING, device, "DIAG initialization "
 419                         "failed (rc=%d)", rc);
 420                 rc = -EIO;
 421         } else {
 422                 DEV_MESSAGE(KERN_INFO, device,
 423                             "(%ld B/blk): %ldkB",
 424                             (unsigned long) device->bp_block,
 425                             (unsigned long) (device->blocks <<
 426                                 device->s2b_shift) >> 1);
 427         }
 428 out:
 429         free_page((long) label);
 430         return rc;
 431 }
 432
 433 /* Fill in virtual disk geometry for device. Return zero on success, non-zero
 434  * otherwise. */
 435 static int
 436 dasd_diag_fill_geometry(struct dasd_device *device, struct hd_geometry *geo)
 437 {
 438         if (dasd_check_blocksize(device->bp_block) != 0)
 439                 return -EINVAL;
 440         geo->cylinders = (device->blocks << device->s2b_shift) >> 10;
 441         geo->heads = 16;
 442         geo->sectors = 128 >> device->s2b_shift;
 443         return 0;
 444 }
 445
 446 static dasd_era_t
 447 dasd_diag_examine_error(struct dasd_ccw_req * cqr, struct irb * stat)
 448 {
 449         return dasd_era_fatal;
 450 }
 451
 452 static dasd_erp_fn_t
 453 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
 454 {
 455         return dasd_default_erp_action;
 456 }
 457
 458 static dasd_erp_fn_t
 459 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
 460 {
 461         return dasd_default_erp_postaction;
 462 }
 463
 464 /* Create DASD request from block device request. Return pointer to new
 465  * request on success, ERR_PTR otherwise. */
 466 static struct dasd_ccw_req *
 467 dasd_diag_build_cp(struct dasd_device * device, struct request *req)
 468 {
 469         struct dasd_ccw_req *cqr;
 470         struct dasd_diag_req *dreq;
 471         struct dasd_diag_bio *dbio;
 472         struct bio *bio;
 473         struct bio_vec *bv;
 474         char *dst;
 475         unsigned int count, datasize;
 476         sector_t recid, first_rec, last_rec;
 477         unsigned int blksize, off;
 478         unsigned char rw_cmd;
 479         int i;
 480
 481         if (rq_data_dir(req) == READ)
 482                 rw_cmd = MDSK_READ_REQ;
 483         else if (rq_data_dir(req) == WRITE)
 484                 rw_cmd = MDSK_WRITE_REQ;
 485         else
 486                 return ERR_PTR(-EINVAL);
 487         blksize = device->bp_block;
 488         /* Calculate record id of first and last block. */
 489         first_rec = req->sector >> device->s2b_shift;
 490         last_rec = (req->sector + req->nr_sectors - 1) >> device->s2b_shift;
 491         /* Check struct bio and count the number of blocks for the request. */
 492         count = 0;
 493         rq_for_each_bio(bio, req) {
 494                 bio_for_each_segment(bv, bio, i) {
 495                         if (bv->bv_len & (blksize - 1))
 496                                 /* Fba can only do full blocks. */
 497                                 return ERR_PTR(-EINVAL);
 498                         count += bv->bv_len >> (device->s2b_shift + 9);
 499                 }
 500         }
 501         /* Paranoia. */
 502         if (count != last_rec - first_rec + 1)
 503                 return ERR_PTR(-EINVAL);
 504         /* Build the request */
 505         datasize = sizeof(struct dasd_diag_req) +
 506                 count*sizeof(struct dasd_diag_bio);
 507         cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0,
 508                                    datasize, device);
 509         if (IS_ERR(cqr))
 510                 return cqr;
 511
 512         dreq = (struct dasd_diag_req *) cqr->data;
 513         dreq->block_count = count;
 514         dbio = dreq->bio;
 515         recid = first_rec;
 516         rq_for_each_bio(bio, req) {
 517                 bio_for_each_segment(bv, bio, i) {
 518                         dst = page_address(bv->bv_page) + bv->bv_offset;
 519                         for (off = 0; off < bv->bv_len; off += blksize) {
 520                                 memset(dbio, 0, sizeof (struct dasd_diag_bio));
 521                                 dbio->type = rw_cmd;
 522                                 dbio->block_number = recid + 1;
 523                                 dbio->buffer = dst;
 524                                 dbio++;
 525                                 dst += blksize;
 526                                 recid++;
 527                         }
 528                 }
 529         }
 530         cqr->retries = DIAG_MAX_RETRIES;
 531         cqr->buildclk = get_clock();
 532         if (req->cmd_flags & REQ_FAILFAST)
 533                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 534         cqr->device = device;
 535         cqr->expires = DIAG_TIMEOUT;
 536         cqr->status = DASD_CQR_FILLED;
 537         return cqr;
 538 }
 539
 540 /* Release DASD request. Return non-zero if request was successful, zero
 541  * otherwise. */
 542 static int
 543 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 544 {
 545         int status;
 546
 547         status = cqr->status == DASD_CQR_DONE;
 548         dasd_sfree_request(cqr, cqr->device);
 549         return status;
 550 }
 551
 552 /* Fill in IOCTL data for device. */
 553 static int
 554 dasd_diag_fill_info(struct dasd_device * device,
 555                     struct dasd_information2_t * info)
 556 {
 557         struct dasd_diag_private *private;
 558
 559         private = (struct dasd_diag_private *) device->private;
 560         info->label_block = (unsigned int) private->pt_block;
 561         info->FBA_layout = 1;
 562         info->format = DASD_FORMAT_LDL;
 563         info->characteristics_size = sizeof (struct dasd_diag_characteristics);
 564         memcpy(info->characteristics,
 565                &((struct dasd_diag_private *) device->private)->rdc_data,
 566                sizeof (struct dasd_diag_characteristics));
 567         info->confdata_size = 0;
 568         return 0;
 569 }
 570
 571 static void
 572 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 573                      struct irb *stat)
 574 {
 575         DEV_MESSAGE(KERN_ERR, device, "%s",
 576                     "dump sense not available for DIAG data");
 577 }
 578
 579 static struct dasd_discipline dasd_diag_discipline = {
 580         .owner = THIS_MODULE,
 581         .name = "DIAG",
 582         .ebcname = "DIAG",
 583         .max_blocks = DIAG_MAX_BLOCKS,
 584         .check_device = dasd_diag_check_device,
 585         .fill_geometry = dasd_diag_fill_geometry,
 586         .start_IO = dasd_start_diag,
 587         .term_IO = dasd_diag_term_IO,
 588         .examine_error = dasd_diag_examine_error,
 589         .erp_action = dasd_diag_erp_action,
 590         .erp_postaction = dasd_diag_erp_postaction,
 591         .build_cp = dasd_diag_build_cp,
 592         .free_cp = dasd_diag_free_cp,
 593         .dump_sense = dasd_diag_dump_sense,
 594         .fill_info = dasd_diag_fill_info,
 595 };
 596
 597 static int __init
 598 dasd_diag_init(void)
 599 {
 600         if (!MACHINE_IS_VM) {
 601                 MESSAGE_LOG(KERN_INFO,
 602                             "Machine is not VM: %s "
 603                             "discipline not initializing",
 604                             dasd_diag_discipline.name);
 605                 return -ENODEV;
 606         }
 607         ASCEBC(dasd_diag_discipline.ebcname, 4);
 608
 609         ctl_set_bit(0, 9);
 610         register_external_interrupt(0x2603, dasd_ext_handler);
 611         dasd_diag_discipline_pointer = &dasd_diag_discipline;
 612         return 0;
 613 }
 614
 615 static void __exit
 616 dasd_diag_cleanup(void)
 617 {
 618         unregister_external_interrupt(0x2603, dasd_ext_handler);
 619         ctl_clear_bit(0, 9);
 620         dasd_diag_discipline_pointer = NULL;
 621 }
 622
 623 module_init(dasd_diag_init);
 624 module_exit(dasd_diag_cleanup);