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