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  * $Revision: 1.53 $
  10  */
  11
  12 #include <linux/config.h>
  13 #include <linux/stddef.h>
  14 #include <linux/kernel.h>
  15 #include <linux/slab.h>
  16 #include <linux/hdreg.h>
  17 #include <linux/bio.h>
  18 #include <linux/module.h>
  19 #include <linux/init.h>
  20 #include <linux/jiffies.h>
  21
  22 #include <asm/dasd.h>
  23 #include <asm/debug.h>
  24 #include <asm/ebcdic.h>
  25 #include <asm/io.h>
  26 #include <asm/s390_ext.h>
  27 #include <asm/todclk.h>
  28 #include <asm/vtoc.h>
  29
  30 #include "dasd_int.h"
  31 #include "dasd_diag.h"
  32
  33 #define PRINTK_HEADER "dasd(diag):"
  34
  35 MODULE_LICENSE("GPL");
  36
  37 /* The maximum number of blocks per request (max_blocks) is dependent on the
  38  * amount of storage that is available in the static I/O buffer for each
  39  * device. Currently each device gets 2 pages. We want to fit two requests
  40  * into the available memory so that we can immediately start the next if one
  41  * finishes. */
  42 #define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \
  43                            sizeof(struct dasd_diag_req)) / \
  44                            sizeof(struct dasd_diag_bio)) / 2)
  45 #define DIAG_MAX_RETRIES        32
  46 #define DIAG_TIMEOUT            50 * HZ
  47
  48 struct dasd_discipline dasd_diag_discipline;
  49
  50 struct dasd_diag_private {
  51         struct dasd_diag_characteristics rdc_data;
  52         struct dasd_diag_rw_io iob;
  53         struct dasd_diag_init_io iib;
  54         blocknum_t pt_block;
  55 };
  56
  57 struct dasd_diag_req {
  58         unsigned int block_count;
  59         struct dasd_diag_bio bio[0];
  60 };
  61
  62 static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */
  63
  64 /* Perform DIAG250 call with block I/O parameter list iob (input and output)
  65  * and function code cmd.
  66  * In case of an exception return 3. Otherwise return result of bitwise OR of
  67  * resulting condition code and DIAG return code. */
  68 static __inline__ int
  69 dia250(void *iob, int cmd)
  70 {
  71         typedef union {
  72                 struct dasd_diag_init_io init_io;
  73                 struct dasd_diag_rw_io rw_io;
  74         } addr_type;
  75         int rc;
  76
  77         __asm__ __volatile__(
  78 #ifdef CONFIG_64BIT
  79                 "       lghi    %0,3\n"
  80                 "       lgr     0,%3\n"
  81                 "       diag    0,%2,0x250\n"
  82                 "0:     ipm     %0\n"
  83                 "       srl     %0,28\n"
  84                 "       or      %0,1\n"
  85                 "1:\n"
  86                 ".section __ex_table,\"a\"\n"
  87                 "       .align 8\n"
  88                 "       .quad  0b,1b\n"
  89                 ".previous\n"
  90 #else
  91                 "       lhi     %0,3\n"
  92                 "       lr      0,%3\n"
  93                 "       diag    0,%2,0x250\n"
  94                 "0:     ipm     %0\n"
  95                 "       srl     %0,28\n"
  96                 "       or      %0,1\n"
  97                 "1:\n"
  98                 ".section __ex_table,\"a\"\n"
  99                 "       .align 4\n"
 100                 "       .long 0b,1b\n"
 101                 ".previous\n"
 102 #endif
 103                 : "=&d" (rc), "=m" (*(addr_type *) iob)
 104                 : "d" (cmd), "d" (iob), "m" (*(addr_type *) iob)
 105                 : "0", "1", "cc");
 106         return rc;
 107 }
 108
 109 /* Initialize block I/O to DIAG device using the specified blocksize and
 110  * block offset. On success, return zero and set end_block to contain the
 111  * number of blocks on the device minus the specified offset. Return non-zero
 112  * otherwise. */
 113 static __inline__ int
 114 mdsk_init_io(struct dasd_device *device, unsigned int blocksize,
 115              blocknum_t offset, blocknum_t *end_block)
 116 {
 117         struct dasd_diag_private *private;
 118         struct dasd_diag_init_io *iib;
 119         int rc;
 120
 121         private = (struct dasd_diag_private *) device->private;
 122         iib = &private->iib;
 123         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 124
 125         iib->dev_nr = _ccw_device_get_device_number(device->cdev);
 126         iib->block_size = blocksize;
 127         iib->offset = offset;
 128         iib->flaga = DASD_DIAG_FLAGA_DEFAULT;
 129
 130         rc = dia250(iib, INIT_BIO);
 131
 132         if ((rc & 3) == 0 && end_block)
 133                 *end_block = iib->end_block;
 134
 135         return rc;
 136 }
 137
 138 /* Remove block I/O environment for device. Return zero on success, non-zero
 139  * otherwise. */
 140 static __inline__ int
 141 mdsk_term_io(struct dasd_device * device)
 142 {
 143         struct dasd_diag_private *private;
 144         struct dasd_diag_init_io *iib;
 145         int rc;
 146
 147         private = (struct dasd_diag_private *) device->private;
 148         iib = &private->iib;
 149         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 150         iib->dev_nr = _ccw_device_get_device_number(device->cdev);
 151         rc = dia250(iib, TERM_BIO);
 152         return rc;
 153 }
 154
 155 /* Error recovery for failed DIAG requests - try to reestablish the DIAG
 156  * environment. */
 157 static void
 158 dasd_diag_erp(struct dasd_device *device)
 159 {
 160         int rc;
 161
 162         mdsk_term_io(device);
 163         rc = mdsk_init_io(device, device->bp_block, 0, NULL);
 164         if (rc)
 165                 DEV_MESSAGE(KERN_WARNING, device, "DIAG ERP unsuccessful, "
 166                             "rc=%d", rc);
 167 }
 168
 169 /* Start a given request at the device. Return zero on success, non-zero
 170  * otherwise. */
 171 static int
 172 dasd_start_diag(struct dasd_ccw_req * cqr)
 173 {
 174         struct dasd_device *device;
 175         struct dasd_diag_private *private;
 176         struct dasd_diag_req *dreq;
 177         int rc;
 178
 179         device = cqr->device;
 180         if (cqr->retries < 0) {
 181                 DEV_MESSAGE(KERN_WARNING, device, "DIAG start_IO: request %p "
 182                             "- no retry left)", cqr);
 183                 cqr->status = DASD_CQR_FAILED;
 184                 return -EIO;
 185         }
 186         private = (struct dasd_diag_private *) device->private;
 187         dreq = (struct dasd_diag_req *) cqr->data;
 188
 189         private->iob.dev_nr = _ccw_device_get_device_number(device->cdev);
 190         private->iob.key = 0;
 191         private->iob.flags = DASD_DIAG_RWFLAG_ASYNC;
 192         private->iob.block_count = dreq->block_count;
 193         private->iob.interrupt_params = (addr_t) cqr;
 194         private->iob.bio_list = dreq->bio;
 195         private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 196
 197         cqr->startclk = get_clock();
 198         cqr->starttime = jiffies;
 199         cqr->retries--;
 200
 201         rc = dia250(&private->iob, RW_BIO);
 202         switch (rc) {
 203         case 0: /* Synchronous I/O finished successfully */
 204                 cqr->stopclk = get_clock();
 205                 cqr->status = DASD_CQR_DONE;
 206                 /* Indicate to calling function that only a dasd_schedule_bh()
 207                    and no timer is needed */
 208                 rc = -EACCES;
 209                 break;
 210         case 8: /* Asynchronous I/O was started */
 211                 cqr->status = DASD_CQR_IN_IO;
 212                 rc = 0;
 213                 break;
 214         default: /* Error condition */
 215                 cqr->status = DASD_CQR_QUEUED;
 216                 DEV_MESSAGE(KERN_WARNING, device, "dia250 returned rc=%d", rc);
 217                 dasd_diag_erp(device);
 218                 rc = -EIO;
 219                 break;
 220         }
 221         return rc;
 222 }
 223
 224 /* Terminate given request at the device. */
 225 static int
 226 dasd_diag_term_IO(struct dasd_ccw_req * cqr)
 227 {
 228         struct dasd_device *device;
 229
 230         device = cqr->device;
 231         mdsk_term_io(device);
 232         mdsk_init_io(device, device->bp_block, 0, NULL);
 233         cqr->status = DASD_CQR_CLEAR;
 234         cqr->stopclk = get_clock();
 235         dasd_schedule_bh(device);
 236         return 0;
 237 }
 238
 239 /* Handle external interruption. */
 240 static void
 241 dasd_ext_handler(struct pt_regs *regs, __u16 code)
 242 {
 243         struct dasd_ccw_req *cqr, *next;
 244         struct dasd_device *device;
 245         unsigned long long expires;
 246         unsigned long flags;
 247         u8 int_code, status;
 248         addr_t ip;
 249         int rc;
 250
 251         int_code = *((u8 *) DASD_DIAG_LC_INT_CODE);
 252         status = *((u8 *) DASD_DIAG_LC_INT_STATUS);
 253         switch (int_code) {
 254         case DASD_DIAG_CODE_31BIT:
 255                 ip = (addr_t) *((u32 *) DASD_DIAG_LC_INT_PARM_31BIT);
 256                 break;
 257         case DASD_DIAG_CODE_64BIT:
 258                 ip = (addr_t) *((u64 *) DASD_DIAG_LC_INT_PARM_64BIT);
 259                 break;
 260         default:
 261                 return;
 262         }
 263         if (!ip) {              /* no intparm: unsolicited interrupt */
 264                 MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt");
 265                 return;
 266         }
 267         cqr = (struct dasd_ccw_req *) ip;
 268         device = (struct dasd_device *) cqr->device;
 269         if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 270                 DEV_MESSAGE(KERN_WARNING, device,
 271                             " magic number of dasd_ccw_req 0x%08X doesn't"
 272                             " match discipline 0x%08X",
 273                             cqr->magic, *(int *) (&device->discipline->name));
 274                 return;
 275         }
 276
 277         /* get irq lock to modify request queue */
 278         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 279
 280         /* Check for a pending clear operation */
 281         if (cqr->status == DASD_CQR_CLEAR) {
 282                 cqr->status = DASD_CQR_QUEUED;
 283                 dasd_clear_timer(device);
 284                 dasd_schedule_bh(device);
 285                 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 286                 return;
 287         }
 288
 289         cqr->stopclk = get_clock();
 290
 291         expires = 0;
 292         if (status == 0) {
 293                 cqr->status = DASD_CQR_DONE;
 294                 /* Start first request on queue if possible -> fast_io. */
 295                 if (!list_empty(&device->ccw_queue)) {
 296                         next = list_entry(device->ccw_queue.next,
 297                                           struct dasd_ccw_req, list);
 298                         if (next->status == DASD_CQR_QUEUED) {
 299                                 rc = dasd_start_diag(next);
 300                                 if (rc == 0)
 301                                         expires = next->expires;
 302                                 else if (rc != -EACCES)
 303                                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 304                                                     "Interrupt fastpath "
 305                                                     "failed!");
 306                         }
 307                 }
 308         } else {
 309                 cqr->status = DASD_CQR_QUEUED;
 310                 DEV_MESSAGE(KERN_WARNING, device, "interrupt status for "
 311                             "request %p was %d (%d retries left)", cqr, status,
 312                             cqr->retries);
 313                 dasd_diag_erp(device);
 314         }
 315
 316         if (expires != 0)
 317                 dasd_set_timer(device, expires);
 318         else
 319                 dasd_clear_timer(device);
 320         dasd_schedule_bh(device);
 321
 322         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 323 }
 324
 325 /* Check whether device can be controlled by DIAG discipline. Return zero on
 326  * success, non-zero otherwise. */
 327 static int
 328 dasd_diag_check_device(struct dasd_device *device)
 329 {
 330         struct dasd_diag_private *private;
 331         struct dasd_diag_characteristics *rdc_data;
 332         struct dasd_diag_bio bio;
 333         struct vtoc_cms_label *label;
 334         blocknum_t end_block;
 335         unsigned int sb, bsize;
 336         int rc;
 337
 338         private = (struct dasd_diag_private *) device->private;
 339         if (private == NULL) {
 340                 private = kmalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
 341                 if (private == NULL) {
 342                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 343                                 "memory allocation failed for private data");
 344                         return -ENOMEM;
 345                 }
 346                 device->private = (void *) private;
 347         }
 348         /* Read Device Characteristics */
 349         rdc_data = (void *) &(private->rdc_data);
 350         rdc_data->dev_nr = _ccw_device_get_device_number(device->cdev);
 351         rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
 352
 353         rc = diag210((struct diag210 *) rdc_data);
 354         if (rc) {
 355                 DEV_MESSAGE(KERN_WARNING, device, "failed to retrieve device "
 356                             "information (rc=%d)", rc);
 357                 return -ENOTSUPP;
 358         }
 359
 360         /* Figure out position of label block */
 361         switch (private->rdc_data.vdev_class) {
 362         case DEV_CLASS_FBA:
 363                 private->pt_block = 1;
 364                 break;
 365         case DEV_CLASS_ECKD:
 366                 private->pt_block = 2;
 367                 break;
 368         default:
 369                 DEV_MESSAGE(KERN_WARNING, device, "unsupported device class "
 370                             "(class=%d)", private->rdc_data.vdev_class);
 371                 return -ENOTSUPP;
 372         }
 373
 374         DBF_DEV_EVENT(DBF_INFO, device,
 375                       "%04X: %04X on real %04X/%02X",
 376                       rdc_data->dev_nr,
 377                       rdc_data->vdev_type,
 378                       rdc_data->rdev_type, rdc_data->rdev_model);
 379
 380         /* terminate all outstanding operations */
 381         mdsk_term_io(device);
 382
 383         /* figure out blocksize of device */
 384         label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL);
 385         if (label == NULL)  {
 386                 DEV_MESSAGE(KERN_WARNING, device, "%s",
 387                             "No memory to allocate initialization request");
 388                 return -ENOMEM;
 389         }
 390         rc = 0;
 391         end_block = 0;
 392         /* try all sizes - needed for ECKD devices */
 393         for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
 394                 mdsk_init_io(device, bsize, 0, &end_block);
 395                 memset(&bio, 0, sizeof (struct dasd_diag_bio));
 396                 bio.type = MDSK_READ_REQ;
 397                 bio.block_number = private->pt_block + 1;
 398                 bio.buffer = label;
 399                 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
 400                 private->iob.dev_nr = rdc_data->dev_nr;
 401                 private->iob.key = 0;
 402                 private->iob.flags = 0; /* do synchronous io */
 403                 private->iob.block_count = 1;
 404                 private->iob.interrupt_params = 0;
 405                 private->iob.bio_list = &bio;
 406                 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 407                 rc = dia250(&private->iob, RW_BIO);
 408                 if (rc == 3) {
 409                         DEV_MESSAGE(KERN_WARNING, device, "%s",
 410                                 "DIAG call failed");
 411                         rc = -EOPNOTSUPP;
 412                         goto out;
 413                 }
 414                 mdsk_term_io(device);
 415                 if (rc == 0)
 416                         break;
 417         }
 418         if (bsize > PAGE_SIZE) {
 419                 DEV_MESSAGE(KERN_WARNING, device, "device access failed "
 420                             "(rc=%d)", rc);
 421                 rc = -EIO;
 422                 goto out;
 423         }
 424         /* check for label block */
 425         if (memcmp(label->label_id, DASD_DIAG_CMS1,
 426                   sizeof(DASD_DIAG_CMS1)) == 0) {
 427                 /* get formatted blocksize from label block */
 428                 bsize = (unsigned int) label->block_size;
 429                 device->blocks = (unsigned long) label->block_count;
 430         } else
 431                 device->blocks = end_block;
 432         device->bp_block = bsize;
 433         device->s2b_shift = 0;  /* bits to shift 512 to get a block */
 434         for (sb = 512; sb < bsize; sb = sb << 1)
 435                 device->s2b_shift++;
 436         rc = mdsk_init_io(device, device->bp_block, 0, NULL);
 437         if (rc) {
 438                 DEV_MESSAGE(KERN_WARNING, device, "DIAG initialization "
 439                         "failed (rc=%d)", rc);
 440                 rc = -EIO;
 441         } else {
 442                 DEV_MESSAGE(KERN_INFO, device,
 443                             "(%ld B/blk): %ldkB",
 444                             (unsigned long) device->bp_block,
 445                             (unsigned long) (device->blocks <<
 446                                 device->s2b_shift) >> 1);
 447         }
 448 out:
 449         free_page((long) label);
 450         return rc;
 451 }
 452
 453 /* Fill in virtual disk geometry for device. Return zero on success, non-zero
 454  * otherwise. */
 455 static int
 456 dasd_diag_fill_geometry(struct dasd_device *device, struct hd_geometry *geo)
 457 {
 458         if (dasd_check_blocksize(device->bp_block) != 0)
 459                 return -EINVAL;
 460         geo->cylinders = (device->blocks << device->s2b_shift) >> 10;
 461         geo->heads = 16;
 462         geo->sectors = 128 >> device->s2b_shift;
 463         return 0;
 464 }
 465
 466 static dasd_era_t
 467 dasd_diag_examine_error(struct dasd_ccw_req * cqr, struct irb * stat)
 468 {
 469         return dasd_era_fatal;
 470 }
 471
 472 static dasd_erp_fn_t
 473 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
 474 {
 475         return dasd_default_erp_action;
 476 }
 477
 478 static dasd_erp_fn_t
 479 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
 480 {
 481         return dasd_default_erp_postaction;
 482 }
 483
 484 /* Create DASD request from block device request. Return pointer to new
 485  * request on success, ERR_PTR otherwise. */
 486 static struct dasd_ccw_req *
 487 dasd_diag_build_cp(struct dasd_device * device, struct request *req)
 488 {
 489         struct dasd_ccw_req *cqr;
 490         struct dasd_diag_req *dreq;
 491         struct dasd_diag_bio *dbio;
 492         struct bio *bio;
 493         struct bio_vec *bv;
 494         char *dst;
 495         unsigned int count, datasize;
 496         sector_t recid, first_rec, last_rec;
 497         unsigned int blksize, off;
 498         unsigned char rw_cmd;
 499         int i;
 500
 501         if (rq_data_dir(req) == READ)
 502                 rw_cmd = MDSK_READ_REQ;
 503         else if (rq_data_dir(req) == WRITE)
 504                 rw_cmd = MDSK_WRITE_REQ;
 505         else
 506                 return ERR_PTR(-EINVAL);
 507         blksize = device->bp_block;
 508         /* Calculate record id of first and last block. */
 509         first_rec = req->sector >> device->s2b_shift;
 510         last_rec = (req->sector + req->nr_sectors - 1) >> device->s2b_shift;
 511         /* Check struct bio and count the number of blocks for the request. */
 512         count = 0;
 513         rq_for_each_bio(bio, req) {
 514                 bio_for_each_segment(bv, bio, i) {
 515                         if (bv->bv_len & (blksize - 1))
 516                                 /* Fba can only do full blocks. */
 517                                 return ERR_PTR(-EINVAL);
 518                         count += bv->bv_len >> (device->s2b_shift + 9);
 519                 }
 520         }
 521         /* Paranoia. */
 522         if (count != last_rec - first_rec + 1)
 523                 return ERR_PTR(-EINVAL);
 524         /* Build the request */
 525         datasize = sizeof(struct dasd_diag_req) +
 526                 count*sizeof(struct dasd_diag_bio);
 527         cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0,
 528                                    datasize, device);
 529         if (IS_ERR(cqr))
 530                 return cqr;
 531
 532         dreq = (struct dasd_diag_req *) cqr->data;
 533         dreq->block_count = count;
 534         dbio = dreq->bio;
 535         recid = first_rec;
 536         rq_for_each_bio(bio, req) {
 537                 bio_for_each_segment(bv, bio, i) {
 538                         dst = page_address(bv->bv_page) + bv->bv_offset;
 539                         for (off = 0; off < bv->bv_len; off += blksize) {
 540                                 memset(dbio, 0, sizeof (struct dasd_diag_bio));
 541                                 dbio->type = rw_cmd;
 542                                 dbio->block_number = recid + 1;
 543                                 dbio->buffer = dst;
 544                                 dbio++;
 545                                 dst += blksize;
 546                                 recid++;
 547                         }
 548                 }
 549         }
 550         cqr->retries = DIAG_MAX_RETRIES;
 551         cqr->buildclk = get_clock();
 552         if (req->flags & REQ_FAILFAST)
 553                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 554         cqr->device = device;
 555         cqr->expires = DIAG_TIMEOUT;
 556         cqr->status = DASD_CQR_FILLED;
 557         return cqr;
 558 }
 559
 560 /* Release DASD request. Return non-zero if request was successful, zero
 561  * otherwise. */
 562 static int
 563 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 564 {
 565         int status;
 566
 567         status = cqr->status == DASD_CQR_DONE;
 568         dasd_sfree_request(cqr, cqr->device);
 569         return status;
 570 }
 571
 572 /* Fill in IOCTL data for device. */
 573 static int
 574 dasd_diag_fill_info(struct dasd_device * device,
 575                     struct dasd_information2_t * info)
 576 {
 577         struct dasd_diag_private *private;
 578
 579         private = (struct dasd_diag_private *) device->private;
 580         info->label_block = (unsigned int) private->pt_block;
 581         info->FBA_layout = 1;
 582         info->format = DASD_FORMAT_LDL;
 583         info->characteristics_size = sizeof (struct dasd_diag_characteristics);
 584         memcpy(info->characteristics,
 585                &((struct dasd_diag_private *) device->private)->rdc_data,
 586                sizeof (struct dasd_diag_characteristics));
 587         info->confdata_size = 0;
 588         return 0;
 589 }
 590
 591 static void
 592 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 593                      struct irb *stat)
 594 {
 595         DEV_MESSAGE(KERN_ERR, device, "%s",
 596                     "dump sense not available for DIAG data");
 597 }
 598
 599 struct dasd_discipline dasd_diag_discipline = {
 600         .owner = THIS_MODULE,
 601         .name = "DIAG",
 602         .ebcname = "DIAG",
 603         .max_blocks = DIAG_MAX_BLOCKS,
 604         .check_device = dasd_diag_check_device,
 605         .fill_geometry = dasd_diag_fill_geometry,
 606         .start_IO = dasd_start_diag,
 607         .term_IO = dasd_diag_term_IO,
 608         .examine_error = dasd_diag_examine_error,
 609         .erp_action = dasd_diag_erp_action,
 610         .erp_postaction = dasd_diag_erp_postaction,
 611         .build_cp = dasd_diag_build_cp,
 612         .free_cp = dasd_diag_free_cp,
 613         .dump_sense = dasd_diag_dump_sense,
 614         .fill_info = dasd_diag_fill_info,
 615 };
 616
 617 static int __init
 618 dasd_diag_init(void)
 619 {
 620         if (!MACHINE_IS_VM) {
 621                 MESSAGE_LOG(KERN_INFO,
 622                             "Machine is not VM: %s "
 623                             "discipline not initializing",
 624                             dasd_diag_discipline.name);
 625                 return -ENODEV;
 626         }
 627         ASCEBC(dasd_diag_discipline.ebcname, 4);
 628
 629         ctl_set_bit(0, 9);
 630         register_external_interrupt(0x2603, dasd_ext_handler);
 631         dasd_diag_discipline_pointer = &dasd_diag_discipline;
 632         return 0;
 633 }
 634
 635 static void __exit
 636 dasd_diag_cleanup(void)
 637 {
 638         unregister_external_interrupt(0x2603, dasd_ext_handler);
 639         ctl_clear_bit(0, 9);
 640         dasd_diag_discipline_pointer = NULL;
 641 }
 642
 643 module_init(dasd_diag_init);
 644 module_exit(dasd_diag_cleanup);