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 #define KMSG_COMPONENT "dasd"
  12
  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 #include <asm/diag.h>
  30
  31 #include "dasd_int.h"
  32 #include "dasd_diag.h"
  33
  34 #define PRINTK_HEADER "dasd(diag):"
  35
  36 MODULE_LICENSE("GPL");
  37
  38 /* The maximum number of blocks per request (max_blocks) is dependent on the
  39  * amount of storage that is available in the static I/O buffer for each
  40  * device. Currently each device gets 2 pages. We want to fit two requests
  41  * into the available memory so that we can immediately start the next if one
  42  * finishes. */
  43 #define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \
  44                            sizeof(struct dasd_diag_req)) / \
  45                            sizeof(struct dasd_diag_bio)) / 2)
  46 #define DIAG_MAX_RETRIES        32
  47 #define DIAG_TIMEOUT            50 * HZ
  48
  49 static struct dasd_discipline dasd_diag_discipline;
  50
  51 struct dasd_diag_private {
  52         struct dasd_diag_characteristics rdc_data;
  53         struct dasd_diag_rw_io iob;
  54         struct dasd_diag_init_io iib;
  55         blocknum_t pt_block;
  56         struct ccw_dev_id dev_id;
  57 };
  58
  59 struct dasd_diag_req {
  60         unsigned int block_count;
  61         struct dasd_diag_bio bio[0];
  62 };
  63
  64 static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */
  65
  66 /* Perform DIAG250 call with block I/O parameter list iob (input and output)
  67  * and function code cmd.
  68  * In case of an exception return 3. Otherwise return result of bitwise OR of
  69  * resulting condition code and DIAG return code. */
  70 static inline int dia250(void *iob, int cmd)
  71 {
  72         register unsigned long reg2 asm ("2") = (unsigned long) iob;
  73         typedef union {
  74                 struct dasd_diag_init_io init_io;
  75                 struct dasd_diag_rw_io rw_io;
  76         } addr_type;
  77         int rc;
  78
  79         rc = 3;
  80         asm volatile(
  81                 "       diag    2,%2,0x250\n"
  82                 "0:     ipm     %0\n"
  83                 "       srl     %0,28\n"
  84                 "       or      %0,3\n"
  85                 "1:\n"
  86                 EX_TABLE(0b,1b)
  87                 : "+d" (rc), "=m" (*(addr_type *) iob)
  88                 : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob)
  89                 : "3", "cc");
  90         return rc;
  91 }
  92
  93 /* Initialize block I/O to DIAG device using the specified blocksize and
  94  * block offset. On success, return zero and set end_block to contain the
  95  * number of blocks on the device minus the specified offset. Return non-zero
  96  * otherwise. */
  97 static inline int
  98 mdsk_init_io(struct dasd_device *device, unsigned int blocksize,
  99              blocknum_t offset, blocknum_t *end_block)
 100 {
 101         struct dasd_diag_private *private;
 102         struct dasd_diag_init_io *iib;
 103         int rc;
 104
 105         private = (struct dasd_diag_private *) device->private;
 106         iib = &private->iib;
 107         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 108
 109         iib->dev_nr = private->dev_id.devno;
 110         iib->block_size = blocksize;
 111         iib->offset = offset;
 112         iib->flaga = DASD_DIAG_FLAGA_DEFAULT;
 113
 114         rc = dia250(iib, INIT_BIO);
 115
 116         if ((rc & 3) == 0 && end_block)
 117                 *end_block = iib->end_block;
 118
 119         return rc;
 120 }
 121
 122 /* Remove block I/O environment for device. Return zero on success, non-zero
 123  * otherwise. */
 124 static inline int
 125 mdsk_term_io(struct dasd_device * device)
 126 {
 127         struct dasd_diag_private *private;
 128         struct dasd_diag_init_io *iib;
 129         int rc;
 130
 131         private = (struct dasd_diag_private *) device->private;
 132         iib = &private->iib;
 133         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 134         iib->dev_nr = private->dev_id.devno;
 135         rc = dia250(iib, TERM_BIO);
 136         return rc;
 137 }
 138
 139 /* Error recovery for failed DIAG requests - try to reestablish the DIAG
 140  * environment. */
 141 static void
 142 dasd_diag_erp(struct dasd_device *device)
 143 {
 144         int rc;
 145
 146         mdsk_term_io(device);
 147         rc = mdsk_init_io(device, device->block->bp_block, 0, NULL);
 148         if (rc)
 149                 dev_warn(&device->cdev->dev, "DIAG ERP failed with "
 150                             "rc=%d\n", rc);
 151 }
 152
 153 /* Start a given request at the device. Return zero on success, non-zero
 154  * otherwise. */
 155 static int
 156 dasd_start_diag(struct dasd_ccw_req * cqr)
 157 {
 158         struct dasd_device *device;
 159         struct dasd_diag_private *private;
 160         struct dasd_diag_req *dreq;
 161         int rc;
 162
 163         device = cqr->startdev;
 164         if (cqr->retries < 0) {
 165                 DBF_DEV_EVENT(DBF_ERR, device, "DIAG start_IO: request %p "
 166                             "- no retry left)", cqr);
 167                 cqr->status = DASD_CQR_ERROR;
 168                 return -EIO;
 169         }
 170         private = (struct dasd_diag_private *) device->private;
 171         dreq = (struct dasd_diag_req *) cqr->data;
 172
 173         private->iob.dev_nr = private->dev_id.devno;
 174         private->iob.key = 0;
 175         private->iob.flags = DASD_DIAG_RWFLAG_ASYNC;
 176         private->iob.block_count = dreq->block_count;
 177         private->iob.interrupt_params = (addr_t) cqr;
 178         private->iob.bio_list = dreq->bio;
 179         private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 180
 181         cqr->startclk = get_clock();
 182         cqr->starttime = jiffies;
 183         cqr->retries--;
 184
 185         rc = dia250(&private->iob, RW_BIO);
 186         switch (rc) {
 187         case 0: /* Synchronous I/O finished successfully */
 188                 cqr->stopclk = get_clock();
 189                 cqr->status = DASD_CQR_SUCCESS;
 190                 /* Indicate to calling function that only a dasd_schedule_bh()
 191                    and no timer is needed */
 192                 rc = -EACCES;
 193                 break;
 194         case 8: /* Asynchronous I/O was started */
 195                 cqr->status = DASD_CQR_IN_IO;
 196                 rc = 0;
 197                 break;
 198         default: /* Error condition */
 199                 cqr->status = DASD_CQR_QUEUED;
 200                 DBF_DEV_EVENT(DBF_WARNING, device, "dia250 returned rc=%d", rc);
 201                 dasd_diag_erp(device);
 202                 rc = -EIO;
 203                 break;
 204         }
 205         return rc;
 206 }
 207
 208 /* Terminate given request at the device. */
 209 static int
 210 dasd_diag_term_IO(struct dasd_ccw_req * cqr)
 211 {
 212         struct dasd_device *device;
 213
 214         device = cqr->startdev;
 215         mdsk_term_io(device);
 216         mdsk_init_io(device, device->block->bp_block, 0, NULL);
 217         cqr->status = DASD_CQR_CLEAR_PENDING;
 218         cqr->stopclk = get_clock();
 219         dasd_schedule_device_bh(device);
 220         return 0;
 221 }
 222
 223 /* Handle external interruption. */
 224 static void
 225 dasd_ext_handler(__u16 code)
 226 {
 227         struct dasd_ccw_req *cqr, *next;
 228         struct dasd_device *device;
 229         unsigned long long expires;
 230         unsigned long flags;
 231         u8 int_code, status;
 232         addr_t ip;
 233         int rc;
 234
 235         int_code = *((u8 *) DASD_DIAG_LC_INT_CODE);
 236         status = *((u8 *) DASD_DIAG_LC_INT_STATUS);
 237         switch (int_code) {
 238         case DASD_DIAG_CODE_31BIT:
 239                 ip = (addr_t) *((u32 *) DASD_DIAG_LC_INT_PARM_31BIT);
 240                 break;
 241         case DASD_DIAG_CODE_64BIT:
 242                 ip = (addr_t) *((u64 *) DASD_DIAG_LC_INT_PARM_64BIT);
 243                 break;
 244         default:
 245                 return;
 246         }
 247         if (!ip) {              /* no intparm: unsolicited interrupt */
 248                 DBF_EVENT(DBF_NOTICE, "%s", "caught unsolicited "
 249                               "interrupt");
 250                 return;
 251         }
 252         cqr = (struct dasd_ccw_req *) ip;
 253         device = (struct dasd_device *) cqr->startdev;
 254         if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 255                 DBF_DEV_EVENT(DBF_WARNING, device,
 256                             " magic number of dasd_ccw_req 0x%08X doesn't"
 257                             " match discipline 0x%08X",
 258                             cqr->magic, *(int *) (&device->discipline->name));
 259                 return;
 260         }
 261
 262         /* get irq lock to modify request queue */
 263         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 264
 265         /* Check for a pending clear operation */
 266         if (cqr->status == DASD_CQR_CLEAR_PENDING) {
 267                 cqr->status = DASD_CQR_CLEARED;
 268                 dasd_device_clear_timer(device);
 269                 dasd_schedule_device_bh(device);
 270                 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 271                 return;
 272         }
 273
 274         cqr->stopclk = get_clock();
 275
 276         expires = 0;
 277         if (status == 0) {
 278                 cqr->status = DASD_CQR_SUCCESS;
 279                 /* Start first request on queue if possible -> fast_io. */
 280                 if (!list_empty(&device->ccw_queue)) {
 281                         next = list_entry(device->ccw_queue.next,
 282                                           struct dasd_ccw_req, devlist);
 283                         if (next->status == DASD_CQR_QUEUED) {
 284                                 rc = dasd_start_diag(next);
 285                                 if (rc == 0)
 286                                         expires = next->expires;
 287                         }
 288                 }
 289         } else {
 290                 cqr->status = DASD_CQR_QUEUED;
 291                 DBF_DEV_EVENT(DBF_DEBUG, device, "interrupt status for "
 292                             "request %p was %d (%d retries left)", cqr, status,
 293                             cqr->retries);
 294                 dasd_diag_erp(device);
 295         }
 296
 297         if (expires != 0)
 298                 dasd_device_set_timer(device, expires);
 299         else
 300                 dasd_device_clear_timer(device);
 301         dasd_schedule_device_bh(device);
 302
 303         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 304 }
 305
 306 /* Check whether device can be controlled by DIAG discipline. Return zero on
 307  * success, non-zero otherwise. */
 308 static int
 309 dasd_diag_check_device(struct dasd_device *device)
 310 {
 311         struct dasd_block *block;
 312         struct dasd_diag_private *private;
 313         struct dasd_diag_characteristics *rdc_data;
 314         struct dasd_diag_bio bio;
 315         struct vtoc_cms_label *label;
 316         blocknum_t end_block;
 317         unsigned int sb, bsize;
 318         int rc;
 319
 320         private = (struct dasd_diag_private *) device->private;
 321         if (private == NULL) {
 322                 private = kzalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
 323                 if (private == NULL) {
 324                         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 325                                 "Allocating memory for private DASD data "
 326                                       "failed\n");
 327                         return -ENOMEM;
 328                 }
 329                 ccw_device_get_id(device->cdev, &private->dev_id);
 330                 device->private = (void *) private;
 331         }
 332         block = dasd_alloc_block();
 333         if (IS_ERR(block)) {
 334                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 335                             "could not allocate dasd block structure");
 336                 device->private = NULL;
 337                 kfree(private);
 338                 return PTR_ERR(block);
 339         }
 340         device->block = block;
 341         block->base = device;
 342
 343         /* Read Device Characteristics */
 344         rdc_data = (void *) &(private->rdc_data);
 345         rdc_data->dev_nr = private->dev_id.devno;
 346         rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
 347
 348         rc = diag210((struct diag210 *) rdc_data);
 349         if (rc) {
 350                 DBF_DEV_EVENT(DBF_WARNING, device, "failed to retrieve device "
 351                             "information (rc=%d)", rc);
 352                 rc = -EOPNOTSUPP;
 353                 goto out;
 354         }
 355
 356         /* Figure out position of label block */
 357         switch (private->rdc_data.vdev_class) {
 358         case DEV_CLASS_FBA:
 359                 private->pt_block = 1;
 360                 break;
 361         case DEV_CLASS_ECKD:
 362                 private->pt_block = 2;
 363                 break;
 364         default:
 365                 dev_warn(&device->cdev->dev, "Device type %d is not supported "
 366                             "in DIAG mode\n", private->rdc_data.vdev_class);
 367                 rc = -EOPNOTSUPP;
 368                 goto out;
 369         }
 370
 371         DBF_DEV_EVENT(DBF_INFO, device,
 372                       "%04X: %04X on real %04X/%02X",
 373                       rdc_data->dev_nr,
 374                       rdc_data->vdev_type,
 375                       rdc_data->rdev_type, rdc_data->rdev_model);
 376
 377         /* terminate all outstanding operations */
 378         mdsk_term_io(device);
 379
 380         /* figure out blocksize of device */
 381         label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL);
 382         if (label == NULL)  {
 383                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 384                             "No memory to allocate initialization request");
 385                 rc = -ENOMEM;
 386                 goto out;
 387         }
 388         rc = 0;
 389         end_block = 0;
 390         /* try all sizes - needed for ECKD devices */
 391         for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
 392                 mdsk_init_io(device, bsize, 0, &end_block);
 393                 memset(&bio, 0, sizeof (struct dasd_diag_bio));
 394                 bio.type = MDSK_READ_REQ;
 395                 bio.block_number = private->pt_block + 1;
 396                 bio.buffer = label;
 397                 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
 398                 private->iob.dev_nr = rdc_data->dev_nr;
 399                 private->iob.key = 0;
 400                 private->iob.flags = 0; /* do synchronous io */
 401                 private->iob.block_count = 1;
 402                 private->iob.interrupt_params = 0;
 403                 private->iob.bio_list = &bio;
 404                 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 405                 rc = dia250(&private->iob, RW_BIO);
 406                 if (rc == 3) {
 407                         dev_warn(&device->cdev->dev,
 408                                 "A 64-bit DIAG call failed\n");
 409                         rc = -EOPNOTSUPP;
 410                         goto out_label;
 411                 }
 412                 mdsk_term_io(device);
 413                 if (rc == 0)
 414                         break;
 415         }
 416         if (bsize > PAGE_SIZE) {
 417                 dev_warn(&device->cdev->dev, "Accessing the DASD failed because"
 418                          " of an incorrect format (rc=%d)\n", rc);
 419                 rc = -EIO;
 420                 goto out_label;
 421         }
 422         /* check for label block */
 423         if (memcmp(label->label_id, DASD_DIAG_CMS1,
 424                   sizeof(DASD_DIAG_CMS1)) == 0) {
 425                 /* get formatted blocksize from label block */
 426                 bsize = (unsigned int) label->block_size;
 427                 block->blocks = (unsigned long) label->block_count;
 428         } else
 429                 block->blocks = end_block;
 430         block->bp_block = bsize;
 431         block->s2b_shift = 0;   /* bits to shift 512 to get a block */
 432         for (sb = 512; sb < bsize; sb = sb << 1)
 433                 block->s2b_shift++;
 434         rc = mdsk_init_io(device, block->bp_block, 0, NULL);
 435         if (rc) {
 436                 dev_warn(&device->cdev->dev, "DIAG initialization "
 437                         "failed with rc=%d\n", rc);
 438                 rc = -EIO;
 439         } else {
 440                 dev_info(&device->cdev->dev,
 441                          "New DASD with %ld byte/block, total size %ld KB\n",
 442                          (unsigned long) block->bp_block,
 443                          (unsigned long) (block->blocks <<
 444                                           block->s2b_shift) >> 1);
 445         }
 446 out_label:
 447         free_page((long) label);
 448 out:
 449         if (rc) {
 450                 device->block = NULL;
 451                 dasd_free_block(block);
 452                 device->private = NULL;
 453                 kfree(private);
 454         }
 455         return rc;
 456 }
 457
 458 /* Fill in virtual disk geometry for device. Return zero on success, non-zero
 459  * otherwise. */
 460 static int
 461 dasd_diag_fill_geometry(struct dasd_block *block, struct hd_geometry *geo)
 462 {
 463         if (dasd_check_blocksize(block->bp_block) != 0)
 464                 return -EINVAL;
 465         geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
 466         geo->heads = 16;
 467         geo->sectors = 128 >> block->s2b_shift;
 468         return 0;
 469 }
 470
 471 static dasd_erp_fn_t
 472 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
 473 {
 474         return dasd_default_erp_action;
 475 }
 476
 477 static dasd_erp_fn_t
 478 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
 479 {
 480         return dasd_default_erp_postaction;
 481 }
 482
 483 /* Create DASD request from block device request. Return pointer to new
 484  * request on success, ERR_PTR otherwise. */
 485 static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev,
 486                                                struct dasd_block *block,
 487                                                struct request *req)
 488 {
 489         struct dasd_ccw_req *cqr;
 490         struct dasd_diag_req *dreq;
 491         struct dasd_diag_bio *dbio;
 492         struct req_iterator iter;
 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
 500         if (rq_data_dir(req) == READ)
 501                 rw_cmd = MDSK_READ_REQ;
 502         else if (rq_data_dir(req) == WRITE)
 503                 rw_cmd = MDSK_WRITE_REQ;
 504         else
 505                 return ERR_PTR(-EINVAL);
 506         blksize = block->bp_block;
 507         /* Calculate record id of first and last block. */
 508         first_rec = blk_rq_pos(req) >> block->s2b_shift;
 509         last_rec =
 510                 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
 511         /* Check struct bio and count the number of blocks for the request. */
 512         count = 0;
 513         rq_for_each_segment(bv, req, iter) {
 514                 if (bv->bv_len & (blksize - 1))
 515                         /* Fba can only do full blocks. */
 516                         return ERR_PTR(-EINVAL);
 517                 count += bv->bv_len >> (block->s2b_shift + 9);
 518         }
 519         /* Paranoia. */
 520         if (count != last_rec - first_rec + 1)
 521                 return ERR_PTR(-EINVAL);
 522         /* Build the request */
 523         datasize = sizeof(struct dasd_diag_req) +
 524                 count*sizeof(struct dasd_diag_bio);
 525         cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0,
 526                                    datasize, memdev);
 527         if (IS_ERR(cqr))
 528                 return cqr;
 529
 530         dreq = (struct dasd_diag_req *) cqr->data;
 531         dreq->block_count = count;
 532         dbio = dreq->bio;
 533         recid = first_rec;
 534         rq_for_each_segment(bv, req, iter) {
 535                 dst = page_address(bv->bv_page) + bv->bv_offset;
 536                 for (off = 0; off < bv->bv_len; off += blksize) {
 537                         memset(dbio, 0, sizeof (struct dasd_diag_bio));
 538                         dbio->type = rw_cmd;
 539                         dbio->block_number = recid + 1;
 540                         dbio->buffer = dst;
 541                         dbio++;
 542                         dst += blksize;
 543                         recid++;
 544                 }
 545         }
 546         cqr->retries = DIAG_MAX_RETRIES;
 547         cqr->buildclk = get_clock();
 548         if (blk_noretry_request(req) ||
 549             block->base->features & DASD_FEATURE_FAILFAST)
 550                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 551         cqr->startdev = memdev;
 552         cqr->memdev = memdev;
 553         cqr->block = block;
 554         cqr->expires = DIAG_TIMEOUT;
 555         cqr->status = DASD_CQR_FILLED;
 556         return cqr;
 557 }
 558
 559 /* Release DASD request. Return non-zero if request was successful, zero
 560  * otherwise. */
 561 static int
 562 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 563 {
 564         int status;
 565
 566         status = cqr->status == DASD_CQR_DONE;
 567         dasd_sfree_request(cqr, cqr->memdev);
 568         return status;
 569 }
 570
 571 static void dasd_diag_handle_terminated_request(struct dasd_ccw_req *cqr)
 572 {
 573         cqr->status = DASD_CQR_FILLED;
 574 };
 575
 576 /* Fill in IOCTL data for device. */
 577 static int
 578 dasd_diag_fill_info(struct dasd_device * device,
 579                     struct dasd_information2_t * info)
 580 {
 581         struct dasd_diag_private *private;
 582
 583         private = (struct dasd_diag_private *) device->private;
 584         info->label_block = (unsigned int) private->pt_block;
 585         info->FBA_layout = 1;
 586         info->format = DASD_FORMAT_LDL;
 587         info->characteristics_size = sizeof (struct dasd_diag_characteristics);
 588         memcpy(info->characteristics,
 589                &((struct dasd_diag_private *) device->private)->rdc_data,
 590                sizeof (struct dasd_diag_characteristics));
 591         info->confdata_size = 0;
 592         return 0;
 593 }
 594
 595 static void
 596 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 597                      struct irb *stat)
 598 {
 599         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 600                     "dump sense not available for DIAG data");
 601 }
 602
 603 static struct dasd_discipline dasd_diag_discipline = {
 604         .owner = THIS_MODULE,
 605         .name = "DIAG",
 606         .ebcname = "DIAG",
 607         .max_blocks = DIAG_MAX_BLOCKS,
 608         .check_device = dasd_diag_check_device,
 609         .fill_geometry = dasd_diag_fill_geometry,
 610         .start_IO = dasd_start_diag,
 611         .term_IO = dasd_diag_term_IO,
 612         .handle_terminated_request = dasd_diag_handle_terminated_request,
 613         .erp_action = dasd_diag_erp_action,
 614         .erp_postaction = dasd_diag_erp_postaction,
 615         .build_cp = dasd_diag_build_cp,
 616         .free_cp = dasd_diag_free_cp,
 617         .dump_sense = dasd_diag_dump_sense,
 618         .fill_info = dasd_diag_fill_info,
 619 };
 620
 621 static int __init
 622 dasd_diag_init(void)
 623 {
 624         if (!MACHINE_IS_VM) {
 625                 pr_info("Discipline %s cannot be used without z/VM\n",
 626                         dasd_diag_discipline.name);
 627                 return -ENODEV;
 628         }
 629         ASCEBC(dasd_diag_discipline.ebcname, 4);
 630
 631         ctl_set_bit(0, 9);
 632         register_external_interrupt(0x2603, dasd_ext_handler);
 633         dasd_diag_discipline_pointer = &dasd_diag_discipline;
 634         return 0;
 635 }
 636
 637 static void __exit
 638 dasd_diag_cleanup(void)
 639 {
 640         unregister_external_interrupt(0x2603, dasd_ext_handler);
 641         ctl_clear_bit(0, 9);
 642         dasd_diag_discipline_pointer = NULL;
 643 }
 644
 645 module_init(dasd_diag_init);
 646 module_exit(dasd_diag_cleanup);