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/ebcdic.h> 25 #include <asm/io.h> 26 #include <asm/irq.h> 27 #include <asm/vtoc.h> 28 #include <asm/diag.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 47 48 static 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 struct ccw_dev_id dev_id; 56 }; 57 58 struct dasd_diag_req { 59 unsigned int block_count; 60 struct dasd_diag_bio bio[0]; 61 }; 62 63 static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */ 64 65 /* Perform DIAG250 call with block I/O parameter list iob (input and output) 66 * and function code cmd. 67 * In case of an exception return 3. Otherwise return result of bitwise OR of 68 * resulting condition code and DIAG return code. */ 69 static inline int dia250(void *iob, int cmd) 70 { 71 register unsigned long reg2 asm ("2") = (unsigned long) iob; 72 typedef union { 73 struct dasd_diag_init_io init_io; 74 struct dasd_diag_rw_io rw_io; 75 } addr_type; 76 int rc; 77 78 rc = 3; 79 asm volatile( 80 " diag 2,%2,0x250\n" 81 "0: ipm %0\n" 82 " srl %0,28\n" 83 " or %0,3\n" 84 "1:\n" 85 EX_TABLE(0b,1b) 86 : "+d" (rc), "=m" (*(addr_type *) iob) 87 : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob) 88 : "3", "cc"); 89 return rc; 90 } 91 92 /* Initialize block I/O to DIAG device using the specified blocksize and 93 * block offset. On success, return zero and set end_block to contain the 94 * number of blocks on the device minus the specified offset. Return non-zero 95 * otherwise. */ 96 static inline int 97 mdsk_init_io(struct dasd_device *device, unsigned int blocksize, 98 blocknum_t offset, blocknum_t *end_block) 99 { 100 struct dasd_diag_private *private; 101 struct dasd_diag_init_io *iib; 102 int rc; 103 104 private = (struct dasd_diag_private *) device->private; 105 iib = &private->iib; 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; 127 struct dasd_diag_init_io *iib; 128 int rc; 129 130 private = (struct dasd_diag_private *) device->private; 131 iib = &private->iib; 132 memset(iib, 0, sizeof (struct dasd_diag_init_io)); 133 iib->dev_nr = private->dev_id.devno; 134 rc = dia250(iib, TERM_BIO); 135 return rc; 136 } 137 138 /* Error recovery for failed DIAG requests - try to reestablish the DIAG 139 * environment. */ 140 static void 141 dasd_diag_erp(struct dasd_device *device) 142 { 143 int rc; 144 145 mdsk_term_io(device); 146 rc = mdsk_init_io(device, device->block->bp_block, 0, NULL); 147 if (rc == 4) { 148 if (!(test_and_set_bit(DASD_FLAG_DEVICE_RO, &device->flags))) 149 pr_warning("%s: The access mode of a DIAG device " 150 "changed to read-only\n", 151 dev_name(&device->cdev->dev)); 152 rc = 0; 153 } 154 if (rc) 155 pr_warning("%s: DIAG ERP failed with " 156 "rc=%d\n", dev_name(&device->cdev->dev), rc); 157 } 158 159 /* Start a given request at the device. Return zero on success, non-zero 160 * otherwise. */ 161 static int 162 dasd_start_diag(struct dasd_ccw_req * cqr) 163 { 164 struct dasd_device *device; 165 struct dasd_diag_private *private; 166 struct dasd_diag_req *dreq; 167 int rc; 168 169 device = cqr->startdev; 170 if (cqr->retries < 0) { 171 DBF_DEV_EVENT(DBF_ERR, device, "DIAG start_IO: request %p " 172 "- no retry left)", cqr); 173 cqr->status = DASD_CQR_ERROR; 174 return -EIO; 175 } 176 private = (struct dasd_diag_private *) device->private; 177 dreq = (struct dasd_diag_req *) cqr->data; 178 179 private->iob.dev_nr = private->dev_id.devno; 180 private->iob.key = 0; 181 private->iob.flags = DASD_DIAG_RWFLAG_ASYNC; 182 private->iob.block_count = dreq->block_count; 183 private->iob.interrupt_params = (addr_t) cqr; 184 private->iob.bio_list = dreq->bio; 185 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; 186 187 cqr->startclk = get_tod_clock(); 188 cqr->starttime = jiffies; 189 cqr->retries--; 190 191 rc = dia250(&private->iob, RW_BIO); 192 switch (rc) { 193 case 0: /* Synchronous I/O finished successfully */ 194 cqr->stopclk = get_tod_clock(); 195 cqr->status = DASD_CQR_SUCCESS; 196 /* Indicate to calling function that only a dasd_schedule_bh() 197 and no timer is needed */ 198 rc = -EACCES; 199 break; 200 case 8: /* Asynchronous I/O was started */ 201 cqr->status = DASD_CQR_IN_IO; 202 rc = 0; 203 break; 204 default: /* Error condition */ 205 cqr->status = DASD_CQR_QUEUED; 206 DBF_DEV_EVENT(DBF_WARNING, device, "dia250 returned rc=%d", rc); 207 dasd_diag_erp(device); 208 rc = -EIO; 209 break; 210 } 211 cqr->intrc = rc; 212 return rc; 213 } 214 215 /* Terminate given request at the device. */ 216 static int 217 dasd_diag_term_IO(struct dasd_ccw_req * cqr) 218 { 219 struct dasd_device *device; 220 221 device = cqr->startdev; 222 mdsk_term_io(device); 223 mdsk_init_io(device, device->block->bp_block, 0, NULL); 224 cqr->status = DASD_CQR_CLEAR_PENDING; 225 cqr->stopclk = get_tod_clock(); 226 dasd_schedule_device_bh(device); 227 return 0; 228 } 229 230 /* Handle external interruption. */ 231 static void dasd_ext_handler(struct ext_code ext_code, 232 unsigned int param32, unsigned long param64) 233 { 234 struct dasd_ccw_req *cqr, *next; 235 struct dasd_device *device; 236 unsigned long long expires; 237 unsigned long flags; 238 addr_t ip; 239 int rc; 240 241 switch (ext_code.subcode >> 8) { 242 case DASD_DIAG_CODE_31BIT: 243 ip = (addr_t) param32; 244 break; 245 case DASD_DIAG_CODE_64BIT: 246 ip = (addr_t) param64; 247 break; 248 default: 249 return; 250 } 251 inc_irq_stat(IRQEXT_DSD); 252 if (!ip) { /* no intparm: unsolicited interrupt */ 253 DBF_EVENT(DBF_NOTICE, "%s", "caught unsolicited " 254 "interrupt"); 255 return; 256 } 257 cqr = (struct dasd_ccw_req *) ip; 258 device = (struct dasd_device *) cqr->startdev; 259 if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) { 260 DBF_DEV_EVENT(DBF_WARNING, device, 261 " magic number of dasd_ccw_req 0x%08X doesn't" 262 " match discipline 0x%08X", 263 cqr->magic, *(int *) (&device->discipline->name)); 264 return; 265 } 266 267 /* get irq lock to modify request queue */ 268 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 269 270 /* Check for a pending clear operation */ 271 if (cqr->status == DASD_CQR_CLEAR_PENDING) { 272 cqr->status = DASD_CQR_CLEARED; 273 dasd_device_clear_timer(device); 274 dasd_schedule_device_bh(device); 275 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 276 return; 277 } 278 279 cqr->stopclk = get_tod_clock(); 280 281 expires = 0; 282 if ((ext_code.subcode & 0xff) == 0) { 283 cqr->status = DASD_CQR_SUCCESS; 284 /* Start first request on queue if possible -> fast_io. */ 285 if (!list_empty(&device->ccw_queue)) { 286 next = list_entry(device->ccw_queue.next, 287 struct dasd_ccw_req, devlist); 288 if (next->status == DASD_CQR_QUEUED) { 289 rc = dasd_start_diag(next); 290 if (rc == 0) 291 expires = next->expires; 292 } 293 } 294 } else { 295 cqr->status = DASD_CQR_QUEUED; 296 DBF_DEV_EVENT(DBF_DEBUG, device, "interrupt status for " 297 "request %p was %d (%d retries left)", cqr, 298 ext_code.subcode & 0xff, cqr->retries); 299 dasd_diag_erp(device); 300 } 301 302 if (expires != 0) 303 dasd_device_set_timer(device, expires); 304 else 305 dasd_device_clear_timer(device); 306 dasd_schedule_device_bh(device); 307 308 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 309 } 310 311 /* Check whether device can be controlled by DIAG discipline. Return zero on 312 * success, non-zero otherwise. */ 313 static int 314 dasd_diag_check_device(struct dasd_device *device) 315 { 316 struct dasd_block *block; 317 struct dasd_diag_private *private; 318 struct dasd_diag_characteristics *rdc_data; 319 struct dasd_diag_bio bio; 320 struct vtoc_cms_label *label; 321 blocknum_t end_block; 322 unsigned int sb, bsize; 323 int rc; 324 325 private = (struct dasd_diag_private *) device->private; 326 if (private == NULL) { 327 private = kzalloc(sizeof(struct dasd_diag_private),GFP_KERNEL); 328 if (private == NULL) { 329 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 330 "Allocating memory for private DASD data " 331 "failed\n"); 332 return -ENOMEM; 333 } 334 ccw_device_get_id(device->cdev, &private->dev_id); 335 device->private = (void *) private; 336 } 337 block = dasd_alloc_block(); 338 if (IS_ERR(block)) { 339 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 340 "could not allocate dasd block structure"); 341 device->private = NULL; 342 kfree(private); 343 return PTR_ERR(block); 344 } 345 device->block = block; 346 block->base = device; 347 348 /* Read Device Characteristics */ 349 rdc_data = (void *) &(private->rdc_data); 350 rdc_data->dev_nr = private->dev_id.devno; 351 rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics); 352 353 rc = diag210((struct diag210 *) rdc_data); 354 if (rc) { 355 DBF_DEV_EVENT(DBF_WARNING, device, "failed to retrieve device " 356 "information (rc=%d)", rc); 357 rc = -EOPNOTSUPP; 358 goto out; 359 } 360 361 device->default_expires = DIAG_TIMEOUT; 362 device->default_retries = DIAG_MAX_RETRIES; 363 364 /* Figure out position of label block */ 365 switch (private->rdc_data.vdev_class) { 366 case DEV_CLASS_FBA: 367 private->pt_block = 1; 368 break; 369 case DEV_CLASS_ECKD: 370 private->pt_block = 2; 371 break; 372 default: 373 pr_warning("%s: Device type %d is not supported " 374 "in DIAG mode\n", dev_name(&device->cdev->dev), 375 private->rdc_data.vdev_class); 376 rc = -EOPNOTSUPP; 377 goto out; 378 } 379 380 DBF_DEV_EVENT(DBF_INFO, device, 381 "%04X: %04X on real %04X/%02X", 382 rdc_data->dev_nr, 383 rdc_data->vdev_type, 384 rdc_data->rdev_type, rdc_data->rdev_model); 385 386 /* terminate all outstanding operations */ 387 mdsk_term_io(device); 388 389 /* figure out blocksize of device */ 390 label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL); 391 if (label == NULL) { 392 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 393 "No memory to allocate initialization request"); 394 rc = -ENOMEM; 395 goto out; 396 } 397 rc = 0; 398 end_block = 0; 399 /* try all sizes - needed for ECKD devices */ 400 for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) { 401 mdsk_init_io(device, bsize, 0, &end_block); 402 memset(&bio, 0, sizeof (struct dasd_diag_bio)); 403 bio.type = MDSK_READ_REQ; 404 bio.block_number = private->pt_block + 1; 405 bio.buffer = label; 406 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io)); 407 private->iob.dev_nr = rdc_data->dev_nr; 408 private->iob.key = 0; 409 private->iob.flags = 0; /* do synchronous io */ 410 private->iob.block_count = 1; 411 private->iob.interrupt_params = 0; 412 private->iob.bio_list = &bio; 413 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; 414 rc = dia250(&private->iob, RW_BIO); 415 if (rc == 3) { 416 pr_warning("%s: A 64-bit DIAG call failed\n", 417 dev_name(&device->cdev->dev)); 418 rc = -EOPNOTSUPP; 419 goto out_label; 420 } 421 mdsk_term_io(device); 422 if (rc == 0) 423 break; 424 } 425 if (bsize > PAGE_SIZE) { 426 pr_warning("%s: Accessing the DASD failed because of an " 427 "incorrect format (rc=%d)\n", 428 dev_name(&device->cdev->dev), rc); 429 rc = -EIO; 430 goto out_label; 431 } 432 /* check for label block */ 433 if (memcmp(label->label_id, DASD_DIAG_CMS1, 434 sizeof(DASD_DIAG_CMS1)) == 0) { 435 /* get formatted blocksize from label block */ 436 bsize = (unsigned int) label->block_size; 437 block->blocks = (unsigned long) label->block_count; 438 } else 439 block->blocks = end_block; 440 block->bp_block = bsize; 441 block->s2b_shift = 0; /* bits to shift 512 to get a block */ 442 for (sb = 512; sb < bsize; sb = sb << 1) 443 block->s2b_shift++; 444 rc = mdsk_init_io(device, block->bp_block, 0, NULL); 445 if (rc && (rc != 4)) { 446 pr_warning("%s: DIAG initialization failed with rc=%d\n", 447 dev_name(&device->cdev->dev), rc); 448 rc = -EIO; 449 } else { 450 if (rc == 4) 451 set_bit(DASD_FLAG_DEVICE_RO, &device->flags); 452 pr_info("%s: New DASD with %ld byte/block, total size %ld " 453 "KB%s\n", dev_name(&device->cdev->dev), 454 (unsigned long) block->bp_block, 455 (unsigned long) (block->blocks << 456 block->s2b_shift) >> 1, 457 (rc == 4) ? ", read-only device" : ""); 458 rc = 0; 459 } 460 out_label: 461 free_page((long) label); 462 out: 463 if (rc) { 464 device->block = NULL; 465 dasd_free_block(block); 466 device->private = NULL; 467 kfree(private); 468 } 469 return rc; 470 } 471 472 /* Fill in virtual disk geometry for device. Return zero on success, non-zero 473 * otherwise. */ 474 static int 475 dasd_diag_fill_geometry(struct dasd_block *block, struct hd_geometry *geo) 476 { 477 if (dasd_check_blocksize(block->bp_block) != 0) 478 return -EINVAL; 479 geo->cylinders = (block->blocks << block->s2b_shift) >> 10; 480 geo->heads = 16; 481 geo->sectors = 128 >> block->s2b_shift; 482 return 0; 483 } 484 485 static dasd_erp_fn_t 486 dasd_diag_erp_action(struct dasd_ccw_req * cqr) 487 { 488 return dasd_default_erp_action; 489 } 490 491 static dasd_erp_fn_t 492 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr) 493 { 494 return dasd_default_erp_postaction; 495 } 496 497 /* Create DASD request from block device request. Return pointer to new 498 * request on success, ERR_PTR otherwise. */ 499 static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev, 500 struct dasd_block *block, 501 struct request *req) 502 { 503 struct dasd_ccw_req *cqr; 504 struct dasd_diag_req *dreq; 505 struct dasd_diag_bio *dbio; 506 struct req_iterator iter; 507 struct bio_vec *bv; 508 char *dst; 509 unsigned int count, datasize; 510 sector_t recid, first_rec, last_rec; 511 unsigned int blksize, off; 512 unsigned char rw_cmd; 513 514 if (rq_data_dir(req) == READ) 515 rw_cmd = MDSK_READ_REQ; 516 else if (rq_data_dir(req) == WRITE) 517 rw_cmd = MDSK_WRITE_REQ; 518 else 519 return ERR_PTR(-EINVAL); 520 blksize = block->bp_block; 521 /* Calculate record id of first and last block. */ 522 first_rec = blk_rq_pos(req) >> block->s2b_shift; 523 last_rec = 524 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift; 525 /* Check struct bio and count the number of blocks for the request. */ 526 count = 0; 527 rq_for_each_segment(bv, req, iter) { 528 if (bv->bv_len & (blksize - 1)) 529 /* Fba can only do full blocks. */ 530 return ERR_PTR(-EINVAL); 531 count += bv->bv_len >> (block->s2b_shift + 9); 532 } 533 /* Paranoia. */ 534 if (count != last_rec - first_rec + 1) 535 return ERR_PTR(-EINVAL); 536 /* Build the request */ 537 datasize = sizeof(struct dasd_diag_req) + 538 count*sizeof(struct dasd_diag_bio); 539 cqr = dasd_smalloc_request(DASD_DIAG_MAGIC, 0, datasize, memdev); 540 if (IS_ERR(cqr)) 541 return cqr; 542 543 dreq = (struct dasd_diag_req *) cqr->data; 544 dreq->block_count = count; 545 dbio = dreq->bio; 546 recid = first_rec; 547 rq_for_each_segment(bv, req, iter) { 548 dst = page_address(bv->bv_page) + bv->bv_offset; 549 for (off = 0; off < bv->bv_len; off += blksize) { 550 memset(dbio, 0, sizeof (struct dasd_diag_bio)); 551 dbio->type = rw_cmd; 552 dbio->block_number = recid + 1; 553 dbio->buffer = dst; 554 dbio++; 555 dst += blksize; 556 recid++; 557 } 558 } 559 cqr->retries = memdev->default_retries; 560 cqr->buildclk = get_tod_clock(); 561 if (blk_noretry_request(req) || 562 block->base->features & DASD_FEATURE_FAILFAST) 563 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); 564 cqr->startdev = memdev; 565 cqr->memdev = memdev; 566 cqr->block = block; 567 cqr->expires = memdev->default_expires * HZ; 568 cqr->status = DASD_CQR_FILLED; 569 return cqr; 570 } 571 572 /* Release DASD request. Return non-zero if request was successful, zero 573 * otherwise. */ 574 static int 575 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req) 576 { 577 int status; 578 579 status = cqr->status == DASD_CQR_DONE; 580 dasd_sfree_request(cqr, cqr->memdev); 581 return status; 582 } 583 584 static void dasd_diag_handle_terminated_request(struct dasd_ccw_req *cqr) 585 { 586 if (cqr->retries < 0) 587 cqr->status = DASD_CQR_FAILED; 588 else 589 cqr->status = DASD_CQR_FILLED; 590 }; 591 592 /* Fill in IOCTL data for device. */ 593 static int 594 dasd_diag_fill_info(struct dasd_device * device, 595 struct dasd_information2_t * info) 596 { 597 struct dasd_diag_private *private; 598 599 private = (struct dasd_diag_private *) device->private; 600 info->label_block = (unsigned int) private->pt_block; 601 info->FBA_layout = 1; 602 info->format = DASD_FORMAT_LDL; 603 info->characteristics_size = sizeof (struct dasd_diag_characteristics); 604 memcpy(info->characteristics, 605 &((struct dasd_diag_private *) device->private)->rdc_data, 606 sizeof (struct dasd_diag_characteristics)); 607 info->confdata_size = 0; 608 return 0; 609 } 610 611 static void 612 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req, 613 struct irb *stat) 614 { 615 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 616 "dump sense not available for DIAG data"); 617 } 618 619 static struct dasd_discipline dasd_diag_discipline = { 620 .owner = THIS_MODULE, 621 .name = "DIAG", 622 .ebcname = "DIAG", 623 .max_blocks = DIAG_MAX_BLOCKS, 624 .check_device = dasd_diag_check_device, 625 .verify_path = dasd_generic_verify_path, 626 .fill_geometry = dasd_diag_fill_geometry, 627 .start_IO = dasd_start_diag, 628 .term_IO = dasd_diag_term_IO, 629 .handle_terminated_request = dasd_diag_handle_terminated_request, 630 .erp_action = dasd_diag_erp_action, 631 .erp_postaction = dasd_diag_erp_postaction, 632 .build_cp = dasd_diag_build_cp, 633 .free_cp = dasd_diag_free_cp, 634 .dump_sense = dasd_diag_dump_sense, 635 .fill_info = dasd_diag_fill_info, 636 }; 637 638 static int __init 639 dasd_diag_init(void) 640 { 641 if (!MACHINE_IS_VM) { 642 pr_info("Discipline %s cannot be used without z/VM\n", 643 dasd_diag_discipline.name); 644 return -ENODEV; 645 } 646 ASCEBC(dasd_diag_discipline.ebcname, 4); 647 648 service_subclass_irq_register(); 649 register_external_interrupt(0x2603, dasd_ext_handler); 650 dasd_diag_discipline_pointer = &dasd_diag_discipline; 651 return 0; 652 } 653 654 static void __exit 655 dasd_diag_cleanup(void) 656 { 657 unregister_external_interrupt(0x2603, dasd_ext_handler); 658 service_subclass_irq_unregister(); 659 dasd_diag_discipline_pointer = NULL; 660 } 661 662 module_init(dasd_diag_init); 663 module_exit(dasd_diag_cleanup); 664