drivers/s390/block/dasd_diag.c

   1 /*
   2  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   3  * Based on.......: linux/drivers/s390/block/mdisk.c
   4  * ...............: by Hartmunt Penner <hpenner@de.ibm.com>
   5  * Bugreports.to..: <Linux390@de.ibm.com>
   6  * Copyright IBM Corp. 1999, 2000
   7  *
   8  */
   9
  10 #define KMSG_COMPONENT "dasd"
  11
  12 #include <linux/kernel_stat.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/diag.h>
  25 #include <asm/ebcdic.h>
  26 #include <asm/io.h>
  27 #include <asm/irq.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
  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         diag_stat_inc(DIAG_STAT_X250);
  81         asm volatile(
  82                 "       diag    2,%2,0x250\n"
  83                 "0:     ipm     %0\n"
  84                 "       srl     %0,28\n"
  85                 "       or      %0,3\n"
  86                 "1:\n"
  87                 EX_TABLE(0b,1b)
  88                 : "+d" (rc), "=m" (*(addr_type *) iob)
  89                 : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob)
  90                 : "3", "cc");
  91         return rc;
  92 }
  93
  94 /* Initialize block I/O to DIAG device using the specified blocksize and
  95  * block offset. On success, return zero and set end_block to contain the
  96  * number of blocks on the device minus the specified offset. Return non-zero
  97  * otherwise. */
  98 static inline int
  99 mdsk_init_io(struct dasd_device *device, unsigned int blocksize,
 100              blocknum_t offset, blocknum_t *end_block)
 101 {
 102         struct dasd_diag_private *private;
 103         struct dasd_diag_init_io *iib;
 104         int rc;
 105
 106         private = (struct dasd_diag_private *) device->private;
 107         iib = &private->iib;
 108         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 109
 110         iib->dev_nr = private->dev_id.devno;
 111         iib->block_size = blocksize;
 112         iib->offset = offset;
 113         iib->flaga = DASD_DIAG_FLAGA_DEFAULT;
 114
 115         rc = dia250(iib, INIT_BIO);
 116
 117         if ((rc & 3) == 0 && end_block)
 118                 *end_block = iib->end_block;
 119
 120         return rc;
 121 }
 122
 123 /* Remove block I/O environment for device. Return zero on success, non-zero
 124  * otherwise. */
 125 static inline int
 126 mdsk_term_io(struct dasd_device * device)
 127 {
 128         struct dasd_diag_private *private;
 129         struct dasd_diag_init_io *iib;
 130         int rc;
 131
 132         private = (struct dasd_diag_private *) device->private;
 133         iib = &private->iib;
 134         memset(iib, 0, sizeof (struct dasd_diag_init_io));
 135         iib->dev_nr = private->dev_id.devno;
 136         rc = dia250(iib, TERM_BIO);
 137         return rc;
 138 }
 139
 140 /* Error recovery for failed DIAG requests - try to reestablish the DIAG
 141  * environment. */
 142 static void
 143 dasd_diag_erp(struct dasd_device *device)
 144 {
 145         int rc;
 146
 147         mdsk_term_io(device);
 148         rc = mdsk_init_io(device, device->block->bp_block, 0, NULL);
 149         if (rc == 4) {
 150                 if (!(test_and_set_bit(DASD_FLAG_DEVICE_RO, &device->flags)))
 151                         pr_warning("%s: The access mode of a DIAG device "
 152                                    "changed to read-only\n",
 153                                    dev_name(&device->cdev->dev));
 154                 rc = 0;
 155         }
 156         if (rc)
 157                 pr_warning("%s: DIAG ERP failed with "
 158                             "rc=%d\n", dev_name(&device->cdev->dev), rc);
 159 }
 160
 161 /* Start a given request at the device. Return zero on success, non-zero
 162  * otherwise. */
 163 static int
 164 dasd_start_diag(struct dasd_ccw_req * cqr)
 165 {
 166         struct dasd_device *device;
 167         struct dasd_diag_private *private;
 168         struct dasd_diag_req *dreq;
 169         int rc;
 170
 171         device = cqr->startdev;
 172         if (cqr->retries < 0) {
 173                 DBF_DEV_EVENT(DBF_ERR, device, "DIAG start_IO: request %p "
 174                             "- no retry left)", cqr);
 175                 cqr->status = DASD_CQR_ERROR;
 176                 return -EIO;
 177         }
 178         private = (struct dasd_diag_private *) device->private;
 179         dreq = (struct dasd_diag_req *) cqr->data;
 180
 181         private->iob.dev_nr = private->dev_id.devno;
 182         private->iob.key = 0;
 183         private->iob.flags = DASD_DIAG_RWFLAG_ASYNC;
 184         private->iob.block_count = dreq->block_count;
 185         private->iob.interrupt_params = (addr_t) cqr;
 186         private->iob.bio_list = dreq->bio;
 187         private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 188
 189         cqr->startclk = get_tod_clock();
 190         cqr->starttime = jiffies;
 191         cqr->retries--;
 192
 193         rc = dia250(&private->iob, RW_BIO);
 194         switch (rc) {
 195         case 0: /* Synchronous I/O finished successfully */
 196                 cqr->stopclk = get_tod_clock();
 197                 cqr->status = DASD_CQR_SUCCESS;
 198                 /* Indicate to calling function that only a dasd_schedule_bh()
 199                    and no timer is needed */
 200                 rc = -EACCES;
 201                 break;
 202         case 8: /* Asynchronous I/O was started */
 203                 cqr->status = DASD_CQR_IN_IO;
 204                 rc = 0;
 205                 break;
 206         default: /* Error condition */
 207                 cqr->status = DASD_CQR_QUEUED;
 208                 DBF_DEV_EVENT(DBF_WARNING, device, "dia250 returned rc=%d", rc);
 209                 dasd_diag_erp(device);
 210                 rc = -EIO;
 211                 break;
 212         }
 213         cqr->intrc = rc;
 214         return rc;
 215 }
 216
 217 /* Terminate given request at the device. */
 218 static int
 219 dasd_diag_term_IO(struct dasd_ccw_req * cqr)
 220 {
 221         struct dasd_device *device;
 222
 223         device = cqr->startdev;
 224         mdsk_term_io(device);
 225         mdsk_init_io(device, device->block->bp_block, 0, NULL);
 226         cqr->status = DASD_CQR_CLEAR_PENDING;
 227         cqr->stopclk = get_tod_clock();
 228         dasd_schedule_device_bh(device);
 229         return 0;
 230 }
 231
 232 /* Handle external interruption. */
 233 static void dasd_ext_handler(struct ext_code ext_code,
 234                              unsigned int param32, unsigned long param64)
 235 {
 236         struct dasd_ccw_req *cqr, *next;
 237         struct dasd_device *device;
 238         unsigned long long expires;
 239         unsigned long flags;
 240         addr_t ip;
 241         int rc;
 242
 243         switch (ext_code.subcode >> 8) {
 244         case DASD_DIAG_CODE_31BIT:
 245                 ip = (addr_t) param32;
 246                 break;
 247         case DASD_DIAG_CODE_64BIT:
 248                 ip = (addr_t) param64;
 249                 break;
 250         default:
 251                 return;
 252         }
 253         inc_irq_stat(IRQEXT_DSD);
 254         if (!ip) {              /* no intparm: unsolicited interrupt */
 255                 DBF_EVENT(DBF_NOTICE, "%s", "caught unsolicited "
 256                               "interrupt");
 257                 return;
 258         }
 259         cqr = (struct dasd_ccw_req *) ip;
 260         device = (struct dasd_device *) cqr->startdev;
 261         if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 262                 DBF_DEV_EVENT(DBF_WARNING, device,
 263                             " magic number of dasd_ccw_req 0x%08X doesn't"
 264                             " match discipline 0x%08X",
 265                             cqr->magic, *(int *) (&device->discipline->name));
 266                 return;
 267         }
 268
 269         /* get irq lock to modify request queue */
 270         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 271
 272         /* Check for a pending clear operation */
 273         if (cqr->status == DASD_CQR_CLEAR_PENDING) {
 274                 cqr->status = DASD_CQR_CLEARED;
 275                 dasd_device_clear_timer(device);
 276                 dasd_schedule_device_bh(device);
 277                 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 278                 return;
 279         }
 280
 281         cqr->stopclk = get_tod_clock();
 282
 283         expires = 0;
 284         if ((ext_code.subcode & 0xff) == 0) {
 285                 cqr->status = DASD_CQR_SUCCESS;
 286                 /* Start first request on queue if possible -> fast_io. */
 287                 if (!list_empty(&device->ccw_queue)) {
 288                         next = list_entry(device->ccw_queue.next,
 289                                           struct dasd_ccw_req, devlist);
 290                         if (next->status == DASD_CQR_QUEUED) {
 291                                 rc = dasd_start_diag(next);
 292                                 if (rc == 0)
 293                                         expires = next->expires;
 294                         }
 295                 }
 296         } else {
 297                 cqr->status = DASD_CQR_QUEUED;
 298                 DBF_DEV_EVENT(DBF_DEBUG, device, "interrupt status for "
 299                               "request %p was %d (%d retries left)", cqr,
 300                               ext_code.subcode & 0xff, cqr->retries);
 301                 dasd_diag_erp(device);
 302         }
 303
 304         if (expires != 0)
 305                 dasd_device_set_timer(device, expires);
 306         else
 307                 dasd_device_clear_timer(device);
 308         dasd_schedule_device_bh(device);
 309
 310         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 311 }
 312
 313 /* Check whether device can be controlled by DIAG discipline. Return zero on
 314  * success, non-zero otherwise. */
 315 static int
 316 dasd_diag_check_device(struct dasd_device *device)
 317 {
 318         struct dasd_block *block;
 319         struct dasd_diag_private *private;
 320         struct dasd_diag_characteristics *rdc_data;
 321         struct dasd_diag_bio bio;
 322         struct vtoc_cms_label *label;
 323         blocknum_t end_block;
 324         unsigned int sb, bsize;
 325         int rc;
 326
 327         private = (struct dasd_diag_private *) device->private;
 328         if (private == NULL) {
 329                 private = kzalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
 330                 if (private == NULL) {
 331                         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 332                                 "Allocating memory for private DASD data "
 333                                       "failed\n");
 334                         return -ENOMEM;
 335                 }
 336                 ccw_device_get_id(device->cdev, &private->dev_id);
 337                 device->private = (void *) private;
 338         }
 339         block = dasd_alloc_block();
 340         if (IS_ERR(block)) {
 341                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 342                             "could not allocate dasd block structure");
 343                 device->private = NULL;
 344                 kfree(private);
 345                 return PTR_ERR(block);
 346         }
 347         device->block = block;
 348         block->base = device;
 349
 350         /* Read Device Characteristics */
 351         rdc_data = (void *) &(private->rdc_data);
 352         rdc_data->dev_nr = private->dev_id.devno;
 353         rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
 354
 355         rc = diag210((struct diag210 *) rdc_data);
 356         if (rc) {
 357                 DBF_DEV_EVENT(DBF_WARNING, device, "failed to retrieve device "
 358                             "information (rc=%d)", rc);
 359                 rc = -EOPNOTSUPP;
 360                 goto out;
 361         }
 362
 363         device->default_expires = DIAG_TIMEOUT;
 364         device->default_retries = DIAG_MAX_RETRIES;
 365
 366         /* Figure out position of label block */
 367         switch (private->rdc_data.vdev_class) {
 368         case DEV_CLASS_FBA:
 369                 private->pt_block = 1;
 370                 break;
 371         case DEV_CLASS_ECKD:
 372                 private->pt_block = 2;
 373                 break;
 374         default:
 375                 pr_warning("%s: Device type %d is not supported "
 376                            "in DIAG mode\n", dev_name(&device->cdev->dev),
 377                            private->rdc_data.vdev_class);
 378                 rc = -EOPNOTSUPP;
 379                 goto out;
 380         }
 381
 382         DBF_DEV_EVENT(DBF_INFO, device,
 383                       "%04X: %04X on real %04X/%02X",
 384                       rdc_data->dev_nr,
 385                       rdc_data->vdev_type,
 386                       rdc_data->rdev_type, rdc_data->rdev_model);
 387
 388         /* terminate all outstanding operations */
 389         mdsk_term_io(device);
 390
 391         /* figure out blocksize of device */
 392         label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL);
 393         if (label == NULL)  {
 394                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 395                             "No memory to allocate initialization request");
 396                 rc = -ENOMEM;
 397                 goto out;
 398         }
 399         rc = 0;
 400         end_block = 0;
 401         /* try all sizes - needed for ECKD devices */
 402         for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
 403                 mdsk_init_io(device, bsize, 0, &end_block);
 404                 memset(&bio, 0, sizeof (struct dasd_diag_bio));
 405                 bio.type = MDSK_READ_REQ;
 406                 bio.block_number = private->pt_block + 1;
 407                 bio.buffer = label;
 408                 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
 409                 private->iob.dev_nr = rdc_data->dev_nr;
 410                 private->iob.key = 0;
 411                 private->iob.flags = 0; /* do synchronous io */
 412                 private->iob.block_count = 1;
 413                 private->iob.interrupt_params = 0;
 414                 private->iob.bio_list = &bio;
 415                 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT;
 416                 rc = dia250(&private->iob, RW_BIO);
 417                 if (rc == 3) {
 418                         pr_warning("%s: A 64-bit DIAG call failed\n",
 419                                    dev_name(&device->cdev->dev));
 420                         rc = -EOPNOTSUPP;
 421                         goto out_label;
 422                 }
 423                 mdsk_term_io(device);
 424                 if (rc == 0)
 425                         break;
 426         }
 427         if (bsize > PAGE_SIZE) {
 428                 pr_warning("%s: Accessing the DASD failed because of an "
 429                            "incorrect format (rc=%d)\n",
 430                            dev_name(&device->cdev->dev), rc);
 431                 rc = -EIO;
 432                 goto out_label;
 433         }
 434         /* check for label block */
 435         if (memcmp(label->label_id, DASD_DIAG_CMS1,
 436                   sizeof(DASD_DIAG_CMS1)) == 0) {
 437                 /* get formatted blocksize from label block */
 438                 bsize = (unsigned int) label->block_size;
 439                 block->blocks = (unsigned long) label->block_count;
 440         } else
 441                 block->blocks = end_block;
 442         block->bp_block = bsize;
 443         block->s2b_shift = 0;   /* bits to shift 512 to get a block */
 444         for (sb = 512; sb < bsize; sb = sb << 1)
 445                 block->s2b_shift++;
 446         rc = mdsk_init_io(device, block->bp_block, 0, NULL);
 447         if (rc && (rc != 4)) {
 448                 pr_warning("%s: DIAG initialization failed with rc=%d\n",
 449                            dev_name(&device->cdev->dev), rc);
 450                 rc = -EIO;
 451         } else {
 452                 if (rc == 4)
 453                         set_bit(DASD_FLAG_DEVICE_RO, &device->flags);
 454                 pr_info("%s: New DASD with %ld byte/block, total size %ld "
 455                         "KB%s\n", dev_name(&device->cdev->dev),
 456                         (unsigned long) block->bp_block,
 457                         (unsigned long) (block->blocks <<
 458                                          block->s2b_shift) >> 1,
 459                         (rc == 4) ? ", read-only device" : "");
 460                 rc = 0;
 461         }
 462 out_label:
 463         free_page((long) label);
 464 out:
 465         if (rc) {
 466                 device->block = NULL;
 467                 dasd_free_block(block);
 468                 device->private = NULL;
 469                 kfree(private);
 470         }
 471         return rc;
 472 }
 473
 474 /* Fill in virtual disk geometry for device. Return zero on success, non-zero
 475  * otherwise. */
 476 static int
 477 dasd_diag_fill_geometry(struct dasd_block *block, struct hd_geometry *geo)
 478 {
 479         if (dasd_check_blocksize(block->bp_block) != 0)
 480                 return -EINVAL;
 481         geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
 482         geo->heads = 16;
 483         geo->sectors = 128 >> block->s2b_shift;
 484         return 0;
 485 }
 486
 487 static dasd_erp_fn_t
 488 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
 489 {
 490         return dasd_default_erp_action;
 491 }
 492
 493 static dasd_erp_fn_t
 494 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
 495 {
 496         return dasd_default_erp_postaction;
 497 }
 498
 499 /* Create DASD request from block device request. Return pointer to new
 500  * request on success, ERR_PTR otherwise. */
 501 static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev,
 502                                                struct dasd_block *block,
 503                                                struct request *req)
 504 {
 505         struct dasd_ccw_req *cqr;
 506         struct dasd_diag_req *dreq;
 507         struct dasd_diag_bio *dbio;
 508         struct req_iterator iter;
 509         struct bio_vec bv;
 510         char *dst;
 511         unsigned int count, datasize;
 512         sector_t recid, first_rec, last_rec;
 513         unsigned int blksize, off;
 514         unsigned char rw_cmd;
 515
 516         if (rq_data_dir(req) == READ)
 517                 rw_cmd = MDSK_READ_REQ;
 518         else if (rq_data_dir(req) == WRITE)
 519                 rw_cmd = MDSK_WRITE_REQ;
 520         else
 521                 return ERR_PTR(-EINVAL);
 522         blksize = block->bp_block;
 523         /* Calculate record id of first and last block. */
 524         first_rec = blk_rq_pos(req) >> block->s2b_shift;
 525         last_rec =
 526                 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
 527         /* Check struct bio and count the number of blocks for the request. */
 528         count = 0;
 529         rq_for_each_segment(bv, req, iter) {
 530                 if (bv.bv_len & (blksize - 1))
 531                         /* Fba can only do full blocks. */
 532                         return ERR_PTR(-EINVAL);
 533                 count += bv.bv_len >> (block->s2b_shift + 9);
 534         }
 535         /* Paranoia. */
 536         if (count != last_rec - first_rec + 1)
 537                 return ERR_PTR(-EINVAL);
 538         /* Build the request */
 539         datasize = sizeof(struct dasd_diag_req) +
 540                 count*sizeof(struct dasd_diag_bio);
 541         cqr = dasd_smalloc_request(DASD_DIAG_MAGIC, 0, datasize, memdev);
 542         if (IS_ERR(cqr))
 543                 return cqr;
 544
 545         dreq = (struct dasd_diag_req *) cqr->data;
 546         dreq->block_count = count;
 547         dbio = dreq->bio;
 548         recid = first_rec;
 549         rq_for_each_segment(bv, req, iter) {
 550                 dst = page_address(bv.bv_page) + bv.bv_offset;
 551                 for (off = 0; off < bv.bv_len; off += blksize) {
 552                         memset(dbio, 0, sizeof (struct dasd_diag_bio));
 553                         dbio->type = rw_cmd;
 554                         dbio->block_number = recid + 1;
 555                         dbio->buffer = dst;
 556                         dbio++;
 557                         dst += blksize;
 558                         recid++;
 559                 }
 560         }
 561         cqr->retries = memdev->default_retries;
 562         cqr->buildclk = get_tod_clock();
 563         if (blk_noretry_request(req) ||
 564             block->base->features & DASD_FEATURE_FAILFAST)
 565                 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
 566         cqr->startdev = memdev;
 567         cqr->memdev = memdev;
 568         cqr->block = block;
 569         cqr->expires = memdev->default_expires * HZ;
 570         cqr->status = DASD_CQR_FILLED;
 571         return cqr;
 572 }
 573
 574 /* Release DASD request. Return non-zero if request was successful, zero
 575  * otherwise. */
 576 static int
 577 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req)
 578 {
 579         int status;
 580
 581         status = cqr->status == DASD_CQR_DONE;
 582         dasd_sfree_request(cqr, cqr->memdev);
 583         return status;
 584 }
 585
 586 static void dasd_diag_handle_terminated_request(struct dasd_ccw_req *cqr)
 587 {
 588         if (cqr->retries < 0)
 589                 cqr->status = DASD_CQR_FAILED;
 590         else
 591                 cqr->status = DASD_CQR_FILLED;
 592 };
 593
 594 /* Fill in IOCTL data for device. */
 595 static int
 596 dasd_diag_fill_info(struct dasd_device * device,
 597                     struct dasd_information2_t * info)
 598 {
 599         struct dasd_diag_private *private;
 600
 601         private = (struct dasd_diag_private *) device->private;
 602         info->label_block = (unsigned int) private->pt_block;
 603         info->FBA_layout = 1;
 604         info->format = DASD_FORMAT_LDL;
 605         info->characteristics_size = sizeof (struct dasd_diag_characteristics);
 606         memcpy(info->characteristics,
 607                &((struct dasd_diag_private *) device->private)->rdc_data,
 608                sizeof (struct dasd_diag_characteristics));
 609         info->confdata_size = 0;
 610         return 0;
 611 }
 612
 613 static void
 614 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
 615                      struct irb *stat)
 616 {
 617         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
 618                     "dump sense not available for DIAG data");
 619 }
 620
 621 static struct dasd_discipline dasd_diag_discipline = {
 622         .owner = THIS_MODULE,
 623         .name = "DIAG",
 624         .ebcname = "DIAG",
 625         .max_blocks = DIAG_MAX_BLOCKS,
 626         .check_device = dasd_diag_check_device,
 627         .verify_path = dasd_generic_verify_path,
 628         .fill_geometry = dasd_diag_fill_geometry,
 629         .start_IO = dasd_start_diag,
 630         .term_IO = dasd_diag_term_IO,
 631         .handle_terminated_request = dasd_diag_handle_terminated_request,
 632         .erp_action = dasd_diag_erp_action,
 633         .erp_postaction = dasd_diag_erp_postaction,
 634         .build_cp = dasd_diag_build_cp,
 635         .free_cp = dasd_diag_free_cp,
 636         .dump_sense = dasd_diag_dump_sense,
 637         .fill_info = dasd_diag_fill_info,
 638 };
 639
 640 static int __init
 641 dasd_diag_init(void)
 642 {
 643         if (!MACHINE_IS_VM) {
 644                 pr_info("Discipline %s cannot be used without z/VM\n",
 645                         dasd_diag_discipline.name);
 646                 return -ENODEV;
 647         }
 648         ASCEBC(dasd_diag_discipline.ebcname, 4);
 649
 650         irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL);
 651         register_external_irq(EXT_IRQ_CP_SERVICE, dasd_ext_handler);
 652         dasd_diag_discipline_pointer = &dasd_diag_discipline;
 653         return 0;
 654 }
 655
 656 static void __exit
 657 dasd_diag_cleanup(void)
 658 {
 659         unregister_external_irq(EXT_IRQ_CP_SERVICE, dasd_ext_handler);
 660         irq_subclass_unregister(IRQ_SUBCLASS_SERVICE_SIGNAL);
 661         dasd_diag_discipline_pointer = NULL;
 662 }
 663
 664 module_init(dasd_diag_init);
 665 module_exit(dasd_diag_cleanup);