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 #include <linux/stddef.h> 12 #include <linux/kernel.h> 13 #include <linux/slab.h> 14 #include <linux/hdreg.h> 15 #include <linux/bio.h> 16 #include <linux/module.h> 17 #include <linux/init.h> 18 #include <linux/jiffies.h> 19 20 #include <asm/dasd.h> 21 #include <asm/debug.h> 22 #include <asm/ebcdic.h> 23 #include <asm/io.h> 24 #include <asm/s390_ext.h> 25 #include <asm/todclk.h> 26 #include <asm/vtoc.h> 27 #include <asm/diag.h> 28 29 #include "dasd_int.h" 30 #include "dasd_diag.h" 31 32 #define PRINTK_HEADER "dasd(diag):" 33 34 MODULE_LICENSE("GPL"); 35 36 /* The maximum number of blocks per request (max_blocks) is dependent on the 37 * amount of storage that is available in the static I/O buffer for each 38 * device. Currently each device gets 2 pages. We want to fit two requests 39 * into the available memory so that we can immediately start the next if one 40 * finishes. */ 41 #define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \ 42 sizeof(struct dasd_diag_req)) / \ 43 sizeof(struct dasd_diag_bio)) / 2) 44 #define DIAG_MAX_RETRIES 32 45 #define DIAG_TIMEOUT 50 * HZ 46 47 static struct dasd_discipline dasd_diag_discipline; 48 49 struct dasd_diag_private { 50 struct dasd_diag_characteristics rdc_data; 51 struct dasd_diag_rw_io iob; 52 struct dasd_diag_init_io iib; 53 blocknum_t pt_block; 54 struct ccw_dev_id dev_id; 55 }; 56 57 struct dasd_diag_req { 58 unsigned int block_count; 59 struct dasd_diag_bio bio[0]; 60 }; 61 62 static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */ 63 64 /* Perform DIAG250 call with block I/O parameter list iob (input and output) 65 * and function code cmd. 66 * In case of an exception return 3. Otherwise return result of bitwise OR of 67 * resulting condition code and DIAG return code. */ 68 static inline int dia250(void *iob, int cmd) 69 { 70 register unsigned long reg2 asm ("2") = (unsigned long) iob; 71 typedef union { 72 struct dasd_diag_init_io init_io; 73 struct dasd_diag_rw_io rw_io; 74 } addr_type; 75 int rc; 76 77 rc = 3; 78 asm volatile( 79 " diag 2,%2,0x250\n" 80 "0: ipm %0\n" 81 " srl %0,28\n" 82 " or %0,3\n" 83 "1:\n" 84 EX_TABLE(0b,1b) 85 : "+d" (rc), "=m" (*(addr_type *) iob) 86 : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob) 87 : "3", "cc"); 88 return rc; 89 } 90 91 /* Initialize block I/O to DIAG device using the specified blocksize and 92 * block offset. On success, return zero and set end_block to contain the 93 * number of blocks on the device minus the specified offset. Return non-zero 94 * otherwise. */ 95 static inline int 96 mdsk_init_io(struct dasd_device *device, unsigned int blocksize, 97 blocknum_t offset, blocknum_t *end_block) 98 { 99 struct dasd_diag_private *private; 100 struct dasd_diag_init_io *iib; 101 int rc; 102 103 private = (struct dasd_diag_private *) device->private; 104 iib = &private->iib; 105 memset(iib, 0, sizeof (struct dasd_diag_init_io)); 106 107 iib->dev_nr = private->dev_id.devno; 108 iib->block_size = blocksize; 109 iib->offset = offset; 110 iib->flaga = DASD_DIAG_FLAGA_DEFAULT; 111 112 rc = dia250(iib, INIT_BIO); 113 114 if ((rc & 3) == 0 && end_block) 115 *end_block = iib->end_block; 116 117 return rc; 118 } 119 120 /* Remove block I/O environment for device. Return zero on success, non-zero 121 * otherwise. */ 122 static inline int 123 mdsk_term_io(struct dasd_device * device) 124 { 125 struct dasd_diag_private *private; 126 struct dasd_diag_init_io *iib; 127 int rc; 128 129 private = (struct dasd_diag_private *) device->private; 130 iib = &private->iib; 131 memset(iib, 0, sizeof (struct dasd_diag_init_io)); 132 iib->dev_nr = private->dev_id.devno; 133 rc = dia250(iib, TERM_BIO); 134 return rc; 135 } 136 137 /* Error recovery for failed DIAG requests - try to reestablish the DIAG 138 * environment. */ 139 static void 140 dasd_diag_erp(struct dasd_device *device) 141 { 142 int rc; 143 144 mdsk_term_io(device); 145 rc = mdsk_init_io(device, device->bp_block, 0, NULL); 146 if (rc) 147 DEV_MESSAGE(KERN_WARNING, device, "DIAG ERP unsuccessful, " 148 "rc=%d", rc); 149 } 150 151 /* Start a given request at the device. Return zero on success, non-zero 152 * otherwise. */ 153 static int 154 dasd_start_diag(struct dasd_ccw_req * cqr) 155 { 156 struct dasd_device *device; 157 struct dasd_diag_private *private; 158 struct dasd_diag_req *dreq; 159 int rc; 160 161 device = cqr->device; 162 if (cqr->retries < 0) { 163 DEV_MESSAGE(KERN_WARNING, device, "DIAG start_IO: request %p " 164 "- no retry left)", cqr); 165 cqr->status = DASD_CQR_FAILED; 166 return -EIO; 167 } 168 private = (struct dasd_diag_private *) device->private; 169 dreq = (struct dasd_diag_req *) cqr->data; 170 171 private->iob.dev_nr = private->dev_id.devno; 172 private->iob.key = 0; 173 private->iob.flags = DASD_DIAG_RWFLAG_ASYNC; 174 private->iob.block_count = dreq->block_count; 175 private->iob.interrupt_params = (addr_t) cqr; 176 private->iob.bio_list = dreq->bio; 177 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; 178 179 cqr->startclk = get_clock(); 180 cqr->starttime = jiffies; 181 cqr->retries--; 182 183 rc = dia250(&private->iob, RW_BIO); 184 switch (rc) { 185 case 0: /* Synchronous I/O finished successfully */ 186 cqr->stopclk = get_clock(); 187 cqr->status = DASD_CQR_DONE; 188 /* Indicate to calling function that only a dasd_schedule_bh() 189 and no timer is needed */ 190 rc = -EACCES; 191 break; 192 case 8: /* Asynchronous I/O was started */ 193 cqr->status = DASD_CQR_IN_IO; 194 rc = 0; 195 break; 196 default: /* Error condition */ 197 cqr->status = DASD_CQR_QUEUED; 198 DEV_MESSAGE(KERN_WARNING, device, "dia250 returned rc=%d", rc); 199 dasd_diag_erp(device); 200 rc = -EIO; 201 break; 202 } 203 return rc; 204 } 205 206 /* Terminate given request at the device. */ 207 static int 208 dasd_diag_term_IO(struct dasd_ccw_req * cqr) 209 { 210 struct dasd_device *device; 211 212 device = cqr->device; 213 mdsk_term_io(device); 214 mdsk_init_io(device, device->bp_block, 0, NULL); 215 cqr->status = DASD_CQR_CLEAR; 216 cqr->stopclk = get_clock(); 217 dasd_schedule_bh(device); 218 return 0; 219 } 220 221 /* Handle external interruption. */ 222 static void 223 dasd_ext_handler(__u16 code) 224 { 225 struct dasd_ccw_req *cqr, *next; 226 struct dasd_device *device; 227 unsigned long long expires; 228 unsigned long flags; 229 u8 int_code, status; 230 addr_t ip; 231 int rc; 232 233 int_code = *((u8 *) DASD_DIAG_LC_INT_CODE); 234 status = *((u8 *) DASD_DIAG_LC_INT_STATUS); 235 switch (int_code) { 236 case DASD_DIAG_CODE_31BIT: 237 ip = (addr_t) *((u32 *) DASD_DIAG_LC_INT_PARM_31BIT); 238 break; 239 case DASD_DIAG_CODE_64BIT: 240 ip = (addr_t) *((u64 *) DASD_DIAG_LC_INT_PARM_64BIT); 241 break; 242 default: 243 return; 244 } 245 if (!ip) { /* no intparm: unsolicited interrupt */ 246 MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt"); 247 return; 248 } 249 cqr = (struct dasd_ccw_req *) ip; 250 device = (struct dasd_device *) cqr->device; 251 if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) { 252 DEV_MESSAGE(KERN_WARNING, device, 253 " magic number of dasd_ccw_req 0x%08X doesn't" 254 " match discipline 0x%08X", 255 cqr->magic, *(int *) (&device->discipline->name)); 256 return; 257 } 258 259 /* get irq lock to modify request queue */ 260 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 261 262 /* Check for a pending clear operation */ 263 if (cqr->status == DASD_CQR_CLEAR) { 264 cqr->status = DASD_CQR_QUEUED; 265 dasd_clear_timer(device); 266 dasd_schedule_bh(device); 267 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 268 return; 269 } 270 271 cqr->stopclk = get_clock(); 272 273 expires = 0; 274 if (status == 0) { 275 cqr->status = DASD_CQR_DONE; 276 /* Start first request on queue if possible -> fast_io. */ 277 if (!list_empty(&device->ccw_queue)) { 278 next = list_entry(device->ccw_queue.next, 279 struct dasd_ccw_req, list); 280 if (next->status == DASD_CQR_QUEUED) { 281 rc = dasd_start_diag(next); 282 if (rc == 0) 283 expires = next->expires; 284 else if (rc != -EACCES) 285 DEV_MESSAGE(KERN_WARNING, device, "%s", 286 "Interrupt fastpath " 287 "failed!"); 288 } 289 } 290 } else { 291 cqr->status = DASD_CQR_QUEUED; 292 DEV_MESSAGE(KERN_WARNING, device, "interrupt status for " 293 "request %p was %d (%d retries left)", cqr, status, 294 cqr->retries); 295 dasd_diag_erp(device); 296 } 297 298 if (expires != 0) 299 dasd_set_timer(device, expires); 300 else 301 dasd_clear_timer(device); 302 dasd_schedule_bh(device); 303 304 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 305 } 306 307 /* Check whether device can be controlled by DIAG discipline. Return zero on 308 * success, non-zero otherwise. */ 309 static int 310 dasd_diag_check_device(struct dasd_device *device) 311 { 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 DEV_MESSAGE(KERN_WARNING, device, "%s", 325 "memory allocation failed for private data"); 326 return -ENOMEM; 327 } 328 ccw_device_get_id(device->cdev, &private->dev_id); 329 device->private = (void *) private; 330 } 331 /* Read Device Characteristics */ 332 rdc_data = (void *) &(private->rdc_data); 333 rdc_data->dev_nr = private->dev_id.devno; 334 rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics); 335 336 rc = diag210((struct diag210 *) rdc_data); 337 if (rc) { 338 DEV_MESSAGE(KERN_WARNING, device, "failed to retrieve device " 339 "information (rc=%d)", rc); 340 return -ENOTSUPP; 341 } 342 343 /* Figure out position of label block */ 344 switch (private->rdc_data.vdev_class) { 345 case DEV_CLASS_FBA: 346 private->pt_block = 1; 347 break; 348 case DEV_CLASS_ECKD: 349 private->pt_block = 2; 350 break; 351 default: 352 DEV_MESSAGE(KERN_WARNING, device, "unsupported device class " 353 "(class=%d)", private->rdc_data.vdev_class); 354 return -ENOTSUPP; 355 } 356 357 DBF_DEV_EVENT(DBF_INFO, device, 358 "%04X: %04X on real %04X/%02X", 359 rdc_data->dev_nr, 360 rdc_data->vdev_type, 361 rdc_data->rdev_type, rdc_data->rdev_model); 362 363 /* terminate all outstanding operations */ 364 mdsk_term_io(device); 365 366 /* figure out blocksize of device */ 367 label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL); 368 if (label == NULL) { 369 DEV_MESSAGE(KERN_WARNING, device, "%s", 370 "No memory to allocate initialization request"); 371 return -ENOMEM; 372 } 373 rc = 0; 374 end_block = 0; 375 /* try all sizes - needed for ECKD devices */ 376 for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) { 377 mdsk_init_io(device, bsize, 0, &end_block); 378 memset(&bio, 0, sizeof (struct dasd_diag_bio)); 379 bio.type = MDSK_READ_REQ; 380 bio.block_number = private->pt_block + 1; 381 bio.buffer = label; 382 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io)); 383 private->iob.dev_nr = rdc_data->dev_nr; 384 private->iob.key = 0; 385 private->iob.flags = 0; /* do synchronous io */ 386 private->iob.block_count = 1; 387 private->iob.interrupt_params = 0; 388 private->iob.bio_list = &bio; 389 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; 390 rc = dia250(&private->iob, RW_BIO); 391 if (rc == 3) { 392 DEV_MESSAGE(KERN_WARNING, device, "%s", 393 "DIAG call failed"); 394 rc = -EOPNOTSUPP; 395 goto out; 396 } 397 mdsk_term_io(device); 398 if (rc == 0) 399 break; 400 } 401 if (bsize > PAGE_SIZE) { 402 DEV_MESSAGE(KERN_WARNING, device, "device access failed " 403 "(rc=%d)", rc); 404 rc = -EIO; 405 goto out; 406 } 407 /* check for label block */ 408 if (memcmp(label->label_id, DASD_DIAG_CMS1, 409 sizeof(DASD_DIAG_CMS1)) == 0) { 410 /* get formatted blocksize from label block */ 411 bsize = (unsigned int) label->block_size; 412 device->blocks = (unsigned long) label->block_count; 413 } else 414 device->blocks = end_block; 415 device->bp_block = bsize; 416 device->s2b_shift = 0; /* bits to shift 512 to get a block */ 417 for (sb = 512; sb < bsize; sb = sb << 1) 418 device->s2b_shift++; 419 rc = mdsk_init_io(device, device->bp_block, 0, NULL); 420 if (rc) { 421 DEV_MESSAGE(KERN_WARNING, device, "DIAG initialization " 422 "failed (rc=%d)", rc); 423 rc = -EIO; 424 } else { 425 DEV_MESSAGE(KERN_INFO, device, 426 "(%ld B/blk): %ldkB", 427 (unsigned long) device->bp_block, 428 (unsigned long) (device->blocks << 429 device->s2b_shift) >> 1); 430 } 431 out: 432 free_page((long) label); 433 return rc; 434 } 435 436 /* Fill in virtual disk geometry for device. Return zero on success, non-zero 437 * otherwise. */ 438 static int 439 dasd_diag_fill_geometry(struct dasd_device *device, struct hd_geometry *geo) 440 { 441 if (dasd_check_blocksize(device->bp_block) != 0) 442 return -EINVAL; 443 geo->cylinders = (device->blocks << device->s2b_shift) >> 10; 444 geo->heads = 16; 445 geo->sectors = 128 >> device->s2b_shift; 446 return 0; 447 } 448 449 static dasd_era_t 450 dasd_diag_examine_error(struct dasd_ccw_req * cqr, struct irb * stat) 451 { 452 return dasd_era_fatal; 453 } 454 455 static dasd_erp_fn_t 456 dasd_diag_erp_action(struct dasd_ccw_req * cqr) 457 { 458 return dasd_default_erp_action; 459 } 460 461 static dasd_erp_fn_t 462 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr) 463 { 464 return dasd_default_erp_postaction; 465 } 466 467 /* Create DASD request from block device request. Return pointer to new 468 * request on success, ERR_PTR otherwise. */ 469 static struct dasd_ccw_req * 470 dasd_diag_build_cp(struct dasd_device * device, struct request *req) 471 { 472 struct dasd_ccw_req *cqr; 473 struct dasd_diag_req *dreq; 474 struct dasd_diag_bio *dbio; 475 struct req_iterator iter; 476 struct bio_vec *bv; 477 char *dst; 478 unsigned int count, datasize; 479 sector_t recid, first_rec, last_rec; 480 unsigned int blksize, off; 481 unsigned char rw_cmd; 482 483 if (rq_data_dir(req) == READ) 484 rw_cmd = MDSK_READ_REQ; 485 else if (rq_data_dir(req) == WRITE) 486 rw_cmd = MDSK_WRITE_REQ; 487 else 488 return ERR_PTR(-EINVAL); 489 blksize = device->bp_block; 490 /* Calculate record id of first and last block. */ 491 first_rec = req->sector >> device->s2b_shift; 492 last_rec = (req->sector + req->nr_sectors - 1) >> device->s2b_shift; 493 /* Check struct bio and count the number of blocks for the request. */ 494 count = 0; 495 rq_for_each_segment(bv, req, iter) { 496 if (bv->bv_len & (blksize - 1)) 497 /* Fba can only do full blocks. */ 498 return ERR_PTR(-EINVAL); 499 count += bv->bv_len >> (device->s2b_shift + 9); 500 } 501 /* Paranoia. */ 502 if (count != last_rec - first_rec + 1) 503 return ERR_PTR(-EINVAL); 504 /* Build the request */ 505 datasize = sizeof(struct dasd_diag_req) + 506 count*sizeof(struct dasd_diag_bio); 507 cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0, 508 datasize, device); 509 if (IS_ERR(cqr)) 510 return cqr; 511 512 dreq = (struct dasd_diag_req *) cqr->data; 513 dreq->block_count = count; 514 dbio = dreq->bio; 515 recid = first_rec; 516 rq_for_each_segment(bv, req, iter) { 517 dst = page_address(bv->bv_page) + bv->bv_offset; 518 for (off = 0; off < bv->bv_len; off += blksize) { 519 memset(dbio, 0, sizeof (struct dasd_diag_bio)); 520 dbio->type = rw_cmd; 521 dbio->block_number = recid + 1; 522 dbio->buffer = dst; 523 dbio++; 524 dst += blksize; 525 recid++; 526 } 527 } 528 cqr->retries = DIAG_MAX_RETRIES; 529 cqr->buildclk = get_clock(); 530 if (req->cmd_flags & REQ_FAILFAST) 531 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); 532 cqr->device = device; 533 cqr->expires = DIAG_TIMEOUT; 534 cqr->status = DASD_CQR_FILLED; 535 return cqr; 536 } 537 538 /* Release DASD request. Return non-zero if request was successful, zero 539 * otherwise. */ 540 static int 541 dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req) 542 { 543 int status; 544 545 status = cqr->status == DASD_CQR_DONE; 546 dasd_sfree_request(cqr, cqr->device); 547 return status; 548 } 549 550 /* Fill in IOCTL data for device. */ 551 static int 552 dasd_diag_fill_info(struct dasd_device * device, 553 struct dasd_information2_t * info) 554 { 555 struct dasd_diag_private *private; 556 557 private = (struct dasd_diag_private *) device->private; 558 info->label_block = (unsigned int) private->pt_block; 559 info->FBA_layout = 1; 560 info->format = DASD_FORMAT_LDL; 561 info->characteristics_size = sizeof (struct dasd_diag_characteristics); 562 memcpy(info->characteristics, 563 &((struct dasd_diag_private *) device->private)->rdc_data, 564 sizeof (struct dasd_diag_characteristics)); 565 info->confdata_size = 0; 566 return 0; 567 } 568 569 static void 570 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req, 571 struct irb *stat) 572 { 573 DEV_MESSAGE(KERN_ERR, device, "%s", 574 "dump sense not available for DIAG data"); 575 } 576 577 static struct dasd_discipline dasd_diag_discipline = { 578 .owner = THIS_MODULE, 579 .name = "DIAG", 580 .ebcname = "DIAG", 581 .max_blocks = DIAG_MAX_BLOCKS, 582 .check_device = dasd_diag_check_device, 583 .fill_geometry = dasd_diag_fill_geometry, 584 .start_IO = dasd_start_diag, 585 .term_IO = dasd_diag_term_IO, 586 .examine_error = dasd_diag_examine_error, 587 .erp_action = dasd_diag_erp_action, 588 .erp_postaction = dasd_diag_erp_postaction, 589 .build_cp = dasd_diag_build_cp, 590 .free_cp = dasd_diag_free_cp, 591 .dump_sense = dasd_diag_dump_sense, 592 .fill_info = dasd_diag_fill_info, 593 }; 594 595 static int __init 596 dasd_diag_init(void) 597 { 598 if (!MACHINE_IS_VM) { 599 MESSAGE_LOG(KERN_INFO, 600 "Machine is not VM: %s " 601 "discipline not initializing", 602 dasd_diag_discipline.name); 603 return -ENODEV; 604 } 605 ASCEBC(dasd_diag_discipline.ebcname, 4); 606 607 ctl_set_bit(0, 9); 608 register_external_interrupt(0x2603, dasd_ext_handler); 609 dasd_diag_discipline_pointer = &dasd_diag_discipline; 610 return 0; 611 } 612 613 static void __exit 614 dasd_diag_cleanup(void) 615 { 616 unregister_external_interrupt(0x2603, dasd_ext_handler); 617 ctl_clear_bit(0, 9); 618 dasd_diag_discipline_pointer = NULL; 619 } 620 621 module_init(dasd_diag_init); 622 module_exit(dasd_diag_cleanup); 623