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/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 35MODULE_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 48static struct dasd_discipline dasd_diag_discipline; 49 50struct 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 58struct dasd_diag_req { 59 unsigned int block_count; 60 struct dasd_diag_bio bio[0]; 61}; 62 63static 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. */ 69static 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. */ 96static inline int 97mdsk_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. */ 123static inline int 124mdsk_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. */ 140static void 141dasd_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. */ 161static int 162dasd_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_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_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. */ 216static int 217dasd_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_clock(); 226 dasd_schedule_device_bh(device); 227 return 0; 228} 229 230/* Handle external interruption. */ 231static void 232dasd_ext_handler(__u16 code) 233{ 234 struct dasd_ccw_req *cqr, *next; 235 struct dasd_device *device; 236 unsigned long long expires; 237 unsigned long flags; 238 u8 int_code, status; 239 addr_t ip; 240 int rc; 241 242 int_code = *((u8 *) DASD_DIAG_LC_INT_CODE); 243 status = *((u8 *) DASD_DIAG_LC_INT_STATUS); 244 switch (int_code) { 245 case DASD_DIAG_CODE_31BIT: 246 ip = (addr_t) *((u32 *) DASD_DIAG_LC_INT_PARM_31BIT); 247 break; 248 case DASD_DIAG_CODE_64BIT: 249 ip = (addr_t) *((u64 *) DASD_DIAG_LC_INT_PARM_64BIT); 250 break; 251 default: 252 return; 253 } 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_clock(); 282 283 expires = 0; 284 if (status == 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, status, 300 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. */ 315static int 316dasd_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; 364 365 /* Figure out position of label block */ 366 switch (private->rdc_data.vdev_class) { 367 case DEV_CLASS_FBA: 368 private->pt_block = 1; 369 break; 370 case DEV_CLASS_ECKD: 371 private->pt_block = 2; 372 break; 373 default: 374 pr_warning("%s: Device type %d is not supported " 375 "in DIAG mode\n", dev_name(&device->cdev->dev), 376 private->rdc_data.vdev_class); 377 rc = -EOPNOTSUPP; 378 goto out; 379 } 380 381 DBF_DEV_EVENT(DBF_INFO, device, 382 "%04X: %04X on real %04X/%02X", 383 rdc_data->dev_nr, 384 rdc_data->vdev_type, 385 rdc_data->rdev_type, rdc_data->rdev_model); 386 387 /* terminate all outstanding operations */ 388 mdsk_term_io(device); 389 390 /* figure out blocksize of device */ 391 label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL); 392 if (label == NULL) { 393 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 394 "No memory to allocate initialization request"); 395 rc = -ENOMEM; 396 goto out; 397 } 398 rc = 0; 399 end_block = 0; 400 /* try all sizes - needed for ECKD devices */ 401 for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) { 402 mdsk_init_io(device, bsize, 0, &end_block); 403 memset(&bio, 0, sizeof (struct dasd_diag_bio)); 404 bio.type = MDSK_READ_REQ; 405 bio.block_number = private->pt_block + 1; 406 bio.buffer = label; 407 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io)); 408 private->iob.dev_nr = rdc_data->dev_nr; 409 private->iob.key = 0; 410 private->iob.flags = 0; /* do synchronous io */ 411 private->iob.block_count = 1; 412 private->iob.interrupt_params = 0; 413 private->iob.bio_list = &bio; 414 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; 415 rc = dia250(&private->iob, RW_BIO); 416 if (rc == 3) { 417 pr_warning("%s: A 64-bit DIAG call failed\n", 418 dev_name(&device->cdev->dev)); 419 rc = -EOPNOTSUPP; 420 goto out_label; 421 } 422 mdsk_term_io(device); 423 if (rc == 0) 424 break; 425 } 426 if (bsize > PAGE_SIZE) { 427 pr_warning("%s: Accessing the DASD failed because of an " 428 "incorrect format (rc=%d)\n", 429 dev_name(&device->cdev->dev), rc); 430 rc = -EIO; 431 goto out_label; 432 } 433 /* check for label block */ 434 if (memcmp(label->label_id, DASD_DIAG_CMS1, 435 sizeof(DASD_DIAG_CMS1)) == 0) { 436 /* get formatted blocksize from label block */ 437 bsize = (unsigned int) label->block_size; 438 block->blocks = (unsigned long) label->block_count; 439 } else 440 block->blocks = end_block; 441 block->bp_block = bsize; 442 block->s2b_shift = 0; /* bits to shift 512 to get a block */ 443 for (sb = 512; sb < bsize; sb = sb << 1) 444 block->s2b_shift++; 445 rc = mdsk_init_io(device, block->bp_block, 0, NULL); 446 if (rc && (rc != 4)) { 447 pr_warning("%s: DIAG initialization failed with rc=%d\n", 448 dev_name(&device->cdev->dev), rc); 449 rc = -EIO; 450 } else { 451 if (rc == 4) 452 set_bit(DASD_FLAG_DEVICE_RO, &device->flags); 453 pr_info("%s: New DASD with %ld byte/block, total size %ld " 454 "KB%s\n", dev_name(&device->cdev->dev), 455 (unsigned long) block->bp_block, 456 (unsigned long) (block->blocks << 457 block->s2b_shift) >> 1, 458 (rc == 4) ? ", read-only device" : ""); 459 rc = 0; 460 } 461out_label: 462 free_page((long) label); 463out: 464 if (rc) { 465 device->block = NULL; 466 dasd_free_block(block); 467 device->private = NULL; 468 kfree(private); 469 } 470 return rc; 471} 472 473/* Fill in virtual disk geometry for device. Return zero on success, non-zero 474 * otherwise. */ 475static int 476dasd_diag_fill_geometry(struct dasd_block *block, struct hd_geometry *geo) 477{ 478 if (dasd_check_blocksize(block->bp_block) != 0) 479 return -EINVAL; 480 geo->cylinders = (block->blocks << block->s2b_shift) >> 10; 481 geo->heads = 16; 482 geo->sectors = 128 >> block->s2b_shift; 483 return 0; 484} 485 486static dasd_erp_fn_t 487dasd_diag_erp_action(struct dasd_ccw_req * cqr) 488{ 489 return dasd_default_erp_action; 490} 491 492static dasd_erp_fn_t 493dasd_diag_erp_postaction(struct dasd_ccw_req * cqr) 494{ 495 return dasd_default_erp_postaction; 496} 497 498/* Create DASD request from block device request. Return pointer to new 499 * request on success, ERR_PTR otherwise. */ 500static struct dasd_ccw_req *dasd_diag_build_cp(struct dasd_device *memdev, 501 struct dasd_block *block, 502 struct request *req) 503{ 504 struct dasd_ccw_req *cqr; 505 struct dasd_diag_req *dreq; 506 struct dasd_diag_bio *dbio; 507 struct req_iterator iter; 508 struct bio_vec *bv; 509 char *dst; 510 unsigned int count, datasize; 511 sector_t recid, first_rec, last_rec; 512 unsigned int blksize, off; 513 unsigned char rw_cmd; 514 515 if (rq_data_dir(req) == READ) 516 rw_cmd = MDSK_READ_REQ; 517 else if (rq_data_dir(req) == WRITE) 518 rw_cmd = MDSK_WRITE_REQ; 519 else 520 return ERR_PTR(-EINVAL); 521 blksize = block->bp_block; 522 /* Calculate record id of first and last block. */ 523 first_rec = blk_rq_pos(req) >> block->s2b_shift; 524 last_rec = 525 (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift; 526 /* Check struct bio and count the number of blocks for the request. */ 527 count = 0; 528 rq_for_each_segment(bv, req, iter) { 529 if (bv->bv_len & (blksize - 1)) 530 /* Fba can only do full blocks. */ 531 return ERR_PTR(-EINVAL); 532 count += bv->bv_len >> (block->s2b_shift + 9); 533 } 534 /* Paranoia. */ 535 if (count != last_rec - first_rec + 1) 536 return ERR_PTR(-EINVAL); 537 /* Build the request */ 538 datasize = sizeof(struct dasd_diag_req) + 539 count*sizeof(struct dasd_diag_bio); 540 cqr = dasd_smalloc_request(DASD_DIAG_MAGIC, 0, datasize, memdev); 541 if (IS_ERR(cqr)) 542 return cqr; 543 544 dreq = (struct dasd_diag_req *) cqr->data; 545 dreq->block_count = count; 546 dbio = dreq->bio; 547 recid = first_rec; 548 rq_for_each_segment(bv, req, iter) { 549 dst = page_address(bv->bv_page) + bv->bv_offset; 550 for (off = 0; off < bv->bv_len; off += blksize) { 551 memset(dbio, 0, sizeof (struct dasd_diag_bio)); 552 dbio->type = rw_cmd; 553 dbio->block_number = recid + 1; 554 dbio->buffer = dst; 555 dbio++; 556 dst += blksize; 557 recid++; 558 } 559 } 560 cqr->retries = DIAG_MAX_RETRIES; 561 cqr->buildclk = get_clock(); 562 if (blk_noretry_request(req) || 563 block->base->features & DASD_FEATURE_FAILFAST) 564 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); 565 cqr->startdev = memdev; 566 cqr->memdev = memdev; 567 cqr->block = block; 568 cqr->expires = memdev->default_expires * HZ; 569 cqr->status = DASD_CQR_FILLED; 570 return cqr; 571} 572 573/* Release DASD request. Return non-zero if request was successful, zero 574 * otherwise. */ 575static int 576dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req) 577{ 578 int status; 579 580 status = cqr->status == DASD_CQR_DONE; 581 dasd_sfree_request(cqr, cqr->memdev); 582 return status; 583} 584 585static void dasd_diag_handle_terminated_request(struct dasd_ccw_req *cqr) 586{ 587 cqr->status = DASD_CQR_FILLED; 588}; 589 590/* Fill in IOCTL data for device. */ 591static int 592dasd_diag_fill_info(struct dasd_device * device, 593 struct dasd_information2_t * info) 594{ 595 struct dasd_diag_private *private; 596 597 private = (struct dasd_diag_private *) device->private; 598 info->label_block = (unsigned int) private->pt_block; 599 info->FBA_layout = 1; 600 info->format = DASD_FORMAT_LDL; 601 info->characteristics_size = sizeof (struct dasd_diag_characteristics); 602 memcpy(info->characteristics, 603 &((struct dasd_diag_private *) device->private)->rdc_data, 604 sizeof (struct dasd_diag_characteristics)); 605 info->confdata_size = 0; 606 return 0; 607} 608 609static void 610dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req, 611 struct irb *stat) 612{ 613 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 614 "dump sense not available for DIAG data"); 615} 616 617static struct dasd_discipline dasd_diag_discipline = { 618 .owner = THIS_MODULE, 619 .name = "DIAG", 620 .ebcname = "DIAG", 621 .max_blocks = DIAG_MAX_BLOCKS, 622 .check_device = dasd_diag_check_device, 623 .fill_geometry = dasd_diag_fill_geometry, 624 .start_IO = dasd_start_diag, 625 .term_IO = dasd_diag_term_IO, 626 .handle_terminated_request = dasd_diag_handle_terminated_request, 627 .erp_action = dasd_diag_erp_action, 628 .erp_postaction = dasd_diag_erp_postaction, 629 .build_cp = dasd_diag_build_cp, 630 .free_cp = dasd_diag_free_cp, 631 .dump_sense = dasd_diag_dump_sense, 632 .fill_info = dasd_diag_fill_info, 633}; 634 635static int __init 636dasd_diag_init(void) 637{ 638 if (!MACHINE_IS_VM) { 639 pr_info("Discipline %s cannot be used without z/VM\n", 640 dasd_diag_discipline.name); 641 return -ENODEV; 642 } 643 ASCEBC(dasd_diag_discipline.ebcname, 4); 644 645 ctl_set_bit(0, 9); 646 register_external_interrupt(0x2603, dasd_ext_handler); 647 dasd_diag_discipline_pointer = &dasd_diag_discipline; 648 return 0; 649} 650 651static void __exit 652dasd_diag_cleanup(void) 653{ 654 unregister_external_interrupt(0x2603, dasd_ext_handler); 655 ctl_clear_bit(0, 9); 656 dasd_diag_discipline_pointer = NULL; 657} 658 659module_init(dasd_diag_init); 660module_exit(dasd_diag_cleanup); 661