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 28#include "dasd_int.h" 29#include "dasd_diag.h" 30 31#define PRINTK_HEADER "dasd(diag):" 32 33MODULE_LICENSE("GPL"); 34 35/* The maximum number of blocks per request (max_blocks) is dependent on the 36 * amount of storage that is available in the static I/O buffer for each 37 * device. Currently each device gets 2 pages. We want to fit two requests 38 * into the available memory so that we can immediately start the next if one 39 * finishes. */ 40#define DIAG_MAX_BLOCKS (((2 * PAGE_SIZE - sizeof(struct dasd_ccw_req) - \ 41 sizeof(struct dasd_diag_req)) / \ 42 sizeof(struct dasd_diag_bio)) / 2) 43#define DIAG_MAX_RETRIES 32 44#define DIAG_TIMEOUT 50 * HZ 45 46static struct dasd_discipline dasd_diag_discipline; 47 48struct dasd_diag_private { 49 struct dasd_diag_characteristics rdc_data; 50 struct dasd_diag_rw_io iob; 51 struct dasd_diag_init_io iib; 52 blocknum_t pt_block; 53 struct ccw_dev_id dev_id; 54}; 55 56struct dasd_diag_req { 57 unsigned int block_count; 58 struct dasd_diag_bio bio[0]; 59}; 60 61static const u8 DASD_DIAG_CMS1[] = { 0xc3, 0xd4, 0xe2, 0xf1 };/* EBCDIC CMS1 */ 62 63/* Perform DIAG250 call with block I/O parameter list iob (input and output) 64 * and function code cmd. 65 * In case of an exception return 3. Otherwise return result of bitwise OR of 66 * resulting condition code and DIAG return code. */ 67static inline int dia250(void *iob, int cmd) 68{ 69 register unsigned long reg2 asm ("2") = (unsigned long) iob; 70 typedef union { 71 struct dasd_diag_init_io init_io; 72 struct dasd_diag_rw_io rw_io; 73 } addr_type; 74 int rc; 75 76 rc = 3; 77 asm volatile( 78 " diag 2,%2,0x250\n" 79 "0: ipm %0\n" 80 " srl %0,28\n" 81 " or %0,3\n" 82 "1:\n" 83 EX_TABLE(0b,1b) 84 : "+d" (rc), "=m" (*(addr_type *) iob) 85 : "d" (cmd), "d" (reg2), "m" (*(addr_type *) iob) 86 : "3", "cc"); 87 return rc; 88} 89 90/* Initialize block I/O to DIAG device using the specified blocksize and 91 * block offset. On success, return zero and set end_block to contain the 92 * number of blocks on the device minus the specified offset. Return non-zero 93 * otherwise. */ 94static inline int 95mdsk_init_io(struct dasd_device *device, unsigned int blocksize, 96 blocknum_t offset, blocknum_t *end_block) 97{ 98 struct dasd_diag_private *private; 99 struct dasd_diag_init_io *iib; 100 int rc; 101 102 private = (struct dasd_diag_private *) device->private; 103 iib = &private->iib; 104 memset(iib, 0, sizeof (struct dasd_diag_init_io)); 105 106 iib->dev_nr = private->dev_id.devno; 107 iib->block_size = blocksize; 108 iib->offset = offset; 109 iib->flaga = DASD_DIAG_FLAGA_DEFAULT; 110 111 rc = dia250(iib, INIT_BIO); 112 113 if ((rc & 3) == 0 && end_block) 114 *end_block = iib->end_block; 115 116 return rc; 117} 118 119/* Remove block I/O environment for device. Return zero on success, non-zero 120 * otherwise. */ 121static inline int 122mdsk_term_io(struct dasd_device * device) 123{ 124 struct dasd_diag_private *private; 125 struct dasd_diag_init_io *iib; 126 int rc; 127 128 private = (struct dasd_diag_private *) device->private; 129 iib = &private->iib; 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. */ 138static void 139dasd_diag_erp(struct dasd_device *device) 140{ 141 int rc; 142 143 mdsk_term_io(device); 144 rc = mdsk_init_io(device, device->bp_block, 0, NULL); 145 if (rc) 146 DEV_MESSAGE(KERN_WARNING, device, "DIAG ERP unsuccessful, " 147 "rc=%d", rc); 148} 149 150/* Start a given request at the device. Return zero on success, non-zero 151 * otherwise. */ 152static int 153dasd_start_diag(struct dasd_ccw_req * cqr) 154{ 155 struct dasd_device *device; 156 struct dasd_diag_private *private; 157 struct dasd_diag_req *dreq; 158 int rc; 159 160 device = cqr->device; 161 if (cqr->retries < 0) { 162 DEV_MESSAGE(KERN_WARNING, device, "DIAG start_IO: request %p " 163 "- no retry left)", cqr); 164 cqr->status = DASD_CQR_FAILED; 165 return -EIO; 166 } 167 private = (struct dasd_diag_private *) device->private; 168 dreq = (struct dasd_diag_req *) cqr->data; 169 170 private->iob.dev_nr = private->dev_id.devno; 171 private->iob.key = 0; 172 private->iob.flags = DASD_DIAG_RWFLAG_ASYNC; 173 private->iob.block_count = dreq->block_count; 174 private->iob.interrupt_params = (addr_t) cqr; 175 private->iob.bio_list = dreq->bio; 176 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; 177 178 cqr->startclk = get_clock(); 179 cqr->starttime = jiffies; 180 cqr->retries--; 181 182 rc = dia250(&private->iob, RW_BIO); 183 switch (rc) { 184 case 0: /* Synchronous I/O finished successfully */ 185 cqr->stopclk = get_clock(); 186 cqr->status = DASD_CQR_DONE; 187 /* Indicate to calling function that only a dasd_schedule_bh() 188 and no timer is needed */ 189 rc = -EACCES; 190 break; 191 case 8: /* Asynchronous I/O was started */ 192 cqr->status = DASD_CQR_IN_IO; 193 rc = 0; 194 break; 195 default: /* Error condition */ 196 cqr->status = DASD_CQR_QUEUED; 197 DEV_MESSAGE(KERN_WARNING, device, "dia250 returned rc=%d", rc); 198 dasd_diag_erp(device); 199 rc = -EIO; 200 break; 201 } 202 return rc; 203} 204 205/* Terminate given request at the device. */ 206static int 207dasd_diag_term_IO(struct dasd_ccw_req * cqr) 208{ 209 struct dasd_device *device; 210 211 device = cqr->device; 212 mdsk_term_io(device); 213 mdsk_init_io(device, device->bp_block, 0, NULL); 214 cqr->status = DASD_CQR_CLEAR; 215 cqr->stopclk = get_clock(); 216 dasd_schedule_bh(device); 217 return 0; 218} 219 220/* Handle external interruption. */ 221static void 222dasd_ext_handler(__u16 code) 223{ 224 struct dasd_ccw_req *cqr, *next; 225 struct dasd_device *device; 226 unsigned long long expires; 227 unsigned long flags; 228 u8 int_code, status; 229 addr_t ip; 230 int rc; 231 232 int_code = *((u8 *) DASD_DIAG_LC_INT_CODE); 233 status = *((u8 *) DASD_DIAG_LC_INT_STATUS); 234 switch (int_code) { 235 case DASD_DIAG_CODE_31BIT: 236 ip = (addr_t) *((u32 *) DASD_DIAG_LC_INT_PARM_31BIT); 237 break; 238 case DASD_DIAG_CODE_64BIT: 239 ip = (addr_t) *((u64 *) DASD_DIAG_LC_INT_PARM_64BIT); 240 break; 241 default: 242 return; 243 } 244 if (!ip) { /* no intparm: unsolicited interrupt */ 245 MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt"); 246 return; 247 } 248 cqr = (struct dasd_ccw_req *) ip; 249 device = (struct dasd_device *) cqr->device; 250 if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) { 251 DEV_MESSAGE(KERN_WARNING, device, 252 " magic number of dasd_ccw_req 0x%08X doesn't" 253 " match discipline 0x%08X", 254 cqr->magic, *(int *) (&device->discipline->name)); 255 return; 256 } 257 258 /* get irq lock to modify request queue */ 259 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 260 261 /* Check for a pending clear operation */ 262 if (cqr->status == DASD_CQR_CLEAR) { 263 cqr->status = DASD_CQR_QUEUED; 264 dasd_clear_timer(device); 265 dasd_schedule_bh(device); 266 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 267 return; 268 } 269 270 cqr->stopclk = get_clock(); 271 272 expires = 0; 273 if (status == 0) { 274 cqr->status = DASD_CQR_DONE; 275 /* Start first request on queue if possible -> fast_io. */ 276 if (!list_empty(&device->ccw_queue)) { 277 next = list_entry(device->ccw_queue.next, 278 struct dasd_ccw_req, list); 279 if (next->status == DASD_CQR_QUEUED) { 280 rc = dasd_start_diag(next); 281 if (rc == 0) 282 expires = next->expires; 283 else if (rc != -EACCES) 284 DEV_MESSAGE(KERN_WARNING, device, "%s", 285 "Interrupt fastpath " 286 "failed!"); 287 } 288 } 289 } else { 290 cqr->status = DASD_CQR_QUEUED; 291 DEV_MESSAGE(KERN_WARNING, device, "interrupt status for " 292 "request %p was %d (%d retries left)", cqr, status, 293 cqr->retries); 294 dasd_diag_erp(device); 295 } 296 297 if (expires != 0) 298 dasd_set_timer(device, expires); 299 else 300 dasd_clear_timer(device); 301 dasd_schedule_bh(device); 302 303 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 304} 305 306/* Check whether device can be controlled by DIAG discipline. Return zero on 307 * success, non-zero otherwise. */ 308static int 309dasd_diag_check_device(struct dasd_device *device) 310{ 311 struct dasd_diag_private *private; 312 struct dasd_diag_characteristics *rdc_data; 313 struct dasd_diag_bio bio; 314 struct vtoc_cms_label *label; 315 blocknum_t end_block; 316 unsigned int sb, bsize; 317 int rc; 318 319 private = (struct dasd_diag_private *) device->private; 320 if (private == NULL) { 321 private = kzalloc(sizeof(struct dasd_diag_private),GFP_KERNEL); 322 if (private == NULL) { 323 DEV_MESSAGE(KERN_WARNING, device, "%s", 324 "memory allocation failed for private data"); 325 return -ENOMEM; 326 } 327 ccw_device_get_id(device->cdev, &private->dev_id); 328 device->private = (void *) private; 329 } 330 /* Read Device Characteristics */ 331 rdc_data = (void *) &(private->rdc_data); 332 rdc_data->dev_nr = private->dev_id.devno; 333 rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics); 334 335 rc = diag210((struct diag210 *) rdc_data); 336 if (rc) { 337 DEV_MESSAGE(KERN_WARNING, device, "failed to retrieve device " 338 "information (rc=%d)", rc); 339 return -ENOTSUPP; 340 } 341 342 /* Figure out position of label block */ 343 switch (private->rdc_data.vdev_class) { 344 case DEV_CLASS_FBA: 345 private->pt_block = 1; 346 break; 347 case DEV_CLASS_ECKD: 348 private->pt_block = 2; 349 break; 350 default: 351 DEV_MESSAGE(KERN_WARNING, device, "unsupported device class " 352 "(class=%d)", private->rdc_data.vdev_class); 353 return -ENOTSUPP; 354 } 355 356 DBF_DEV_EVENT(DBF_INFO, device, 357 "%04X: %04X on real %04X/%02X", 358 rdc_data->dev_nr, 359 rdc_data->vdev_type, 360 rdc_data->rdev_type, rdc_data->rdev_model); 361 362 /* terminate all outstanding operations */ 363 mdsk_term_io(device); 364 365 /* figure out blocksize of device */ 366 label = (struct vtoc_cms_label *) get_zeroed_page(GFP_KERNEL); 367 if (label == NULL) { 368 DEV_MESSAGE(KERN_WARNING, device, "%s", 369 "No memory to allocate initialization request"); 370 return -ENOMEM; 371 } 372 rc = 0; 373 end_block = 0; 374 /* try all sizes - needed for ECKD devices */ 375 for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) { 376 mdsk_init_io(device, bsize, 0, &end_block); 377 memset(&bio, 0, sizeof (struct dasd_diag_bio)); 378 bio.type = MDSK_READ_REQ; 379 bio.block_number = private->pt_block + 1; 380 bio.buffer = label; 381 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io)); 382 private->iob.dev_nr = rdc_data->dev_nr; 383 private->iob.key = 0; 384 private->iob.flags = 0; /* do synchronous io */ 385 private->iob.block_count = 1; 386 private->iob.interrupt_params = 0; 387 private->iob.bio_list = &bio; 388 private->iob.flaga = DASD_DIAG_FLAGA_DEFAULT; 389 rc = dia250(&private->iob, RW_BIO); 390 if (rc == 3) { 391 DEV_MESSAGE(KERN_WARNING, device, "%s", 392 "DIAG call failed"); 393 rc = -EOPNOTSUPP; 394 goto out; 395 } 396 mdsk_term_io(device); 397 if (rc == 0) 398 break; 399 } 400 if (bsize > PAGE_SIZE) { 401 DEV_MESSAGE(KERN_WARNING, device, "device access failed " 402 "(rc=%d)", rc); 403 rc = -EIO; 404 goto out; 405 } 406 /* check for label block */ 407 if (memcmp(label->label_id, DASD_DIAG_CMS1, 408 sizeof(DASD_DIAG_CMS1)) == 0) { 409 /* get formatted blocksize from label block */ 410 bsize = (unsigned int) label->block_size; 411 device->blocks = (unsigned long) label->block_count; 412 } else 413 device->blocks = end_block; 414 device->bp_block = bsize; 415 device->s2b_shift = 0; /* bits to shift 512 to get a block */ 416 for (sb = 512; sb < bsize; sb = sb << 1) 417 device->s2b_shift++; 418 rc = mdsk_init_io(device, device->bp_block, 0, NULL); 419 if (rc) { 420 DEV_MESSAGE(KERN_WARNING, device, "DIAG initialization " 421 "failed (rc=%d)", rc); 422 rc = -EIO; 423 } else { 424 DEV_MESSAGE(KERN_INFO, device, 425 "(%ld B/blk): %ldkB", 426 (unsigned long) device->bp_block, 427 (unsigned long) (device->blocks << 428 device->s2b_shift) >> 1); 429 } 430out: 431 free_page((long) label); 432 return rc; 433} 434 435/* Fill in virtual disk geometry for device. Return zero on success, non-zero 436 * otherwise. */ 437static int 438dasd_diag_fill_geometry(struct dasd_device *device, struct hd_geometry *geo) 439{ 440 if (dasd_check_blocksize(device->bp_block) != 0) 441 return -EINVAL; 442 geo->cylinders = (device->blocks << device->s2b_shift) >> 10; 443 geo->heads = 16; 444 geo->sectors = 128 >> device->s2b_shift; 445 return 0; 446} 447 448static dasd_era_t 449dasd_diag_examine_error(struct dasd_ccw_req * cqr, struct irb * stat) 450{ 451 return dasd_era_fatal; 452} 453 454static dasd_erp_fn_t 455dasd_diag_erp_action(struct dasd_ccw_req * cqr) 456{ 457 return dasd_default_erp_action; 458} 459 460static dasd_erp_fn_t 461dasd_diag_erp_postaction(struct dasd_ccw_req * cqr) 462{ 463 return dasd_default_erp_postaction; 464} 465 466/* Create DASD request from block device request. Return pointer to new 467 * request on success, ERR_PTR otherwise. */ 468static struct dasd_ccw_req * 469dasd_diag_build_cp(struct dasd_device * device, struct request *req) 470{ 471 struct dasd_ccw_req *cqr; 472 struct dasd_diag_req *dreq; 473 struct dasd_diag_bio *dbio; 474 struct bio *bio; 475 struct bio_vec *bv; 476 char *dst; 477 unsigned int count, datasize; 478 sector_t recid, first_rec, last_rec; 479 unsigned int blksize, off; 480 unsigned char rw_cmd; 481 int i; 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_bio(bio, req) { 496 bio_for_each_segment(bv, bio, i) { 497 if (bv->bv_len & (blksize - 1)) 498 /* Fba can only do full blocks. */ 499 return ERR_PTR(-EINVAL); 500 count += bv->bv_len >> (device->s2b_shift + 9); 501 } 502 } 503 /* Paranoia. */ 504 if (count != last_rec - first_rec + 1) 505 return ERR_PTR(-EINVAL); 506 /* Build the request */ 507 datasize = sizeof(struct dasd_diag_req) + 508 count*sizeof(struct dasd_diag_bio); 509 cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0, 510 datasize, device); 511 if (IS_ERR(cqr)) 512 return cqr; 513 514 dreq = (struct dasd_diag_req *) cqr->data; 515 dreq->block_count = count; 516 dbio = dreq->bio; 517 recid = first_rec; 518 rq_for_each_bio(bio, req) { 519 bio_for_each_segment(bv, bio, i) { 520 dst = page_address(bv->bv_page) + bv->bv_offset; 521 for (off = 0; off < bv->bv_len; off += blksize) { 522 memset(dbio, 0, sizeof (struct dasd_diag_bio)); 523 dbio->type = rw_cmd; 524 dbio->block_number = recid + 1; 525 dbio->buffer = dst; 526 dbio++; 527 dst += blksize; 528 recid++; 529 } 530 } 531 } 532 cqr->retries = DIAG_MAX_RETRIES; 533 cqr->buildclk = get_clock(); 534 if (req->cmd_flags & REQ_FAILFAST) 535 set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags); 536 cqr->device = device; 537 cqr->expires = DIAG_TIMEOUT; 538 cqr->status = DASD_CQR_FILLED; 539 return cqr; 540} 541 542/* Release DASD request. Return non-zero if request was successful, zero 543 * otherwise. */ 544static int 545dasd_diag_free_cp(struct dasd_ccw_req *cqr, struct request *req) 546{ 547 int status; 548 549 status = cqr->status == DASD_CQR_DONE; 550 dasd_sfree_request(cqr, cqr->device); 551 return status; 552} 553 554/* Fill in IOCTL data for device. */ 555static int 556dasd_diag_fill_info(struct dasd_device * device, 557 struct dasd_information2_t * info) 558{ 559 struct dasd_diag_private *private; 560 561 private = (struct dasd_diag_private *) device->private; 562 info->label_block = (unsigned int) private->pt_block; 563 info->FBA_layout = 1; 564 info->format = DASD_FORMAT_LDL; 565 info->characteristics_size = sizeof (struct dasd_diag_characteristics); 566 memcpy(info->characteristics, 567 &((struct dasd_diag_private *) device->private)->rdc_data, 568 sizeof (struct dasd_diag_characteristics)); 569 info->confdata_size = 0; 570 return 0; 571} 572 573static void 574dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req, 575 struct irb *stat) 576{ 577 DEV_MESSAGE(KERN_ERR, device, "%s", 578 "dump sense not available for DIAG data"); 579} 580 581static struct dasd_discipline dasd_diag_discipline = { 582 .owner = THIS_MODULE, 583 .name = "DIAG", 584 .ebcname = "DIAG", 585 .max_blocks = DIAG_MAX_BLOCKS, 586 .check_device = dasd_diag_check_device, 587 .fill_geometry = dasd_diag_fill_geometry, 588 .start_IO = dasd_start_diag, 589 .term_IO = dasd_diag_term_IO, 590 .examine_error = dasd_diag_examine_error, 591 .erp_action = dasd_diag_erp_action, 592 .erp_postaction = dasd_diag_erp_postaction, 593 .build_cp = dasd_diag_build_cp, 594 .free_cp = dasd_diag_free_cp, 595 .dump_sense = dasd_diag_dump_sense, 596 .fill_info = dasd_diag_fill_info, 597}; 598 599static int __init 600dasd_diag_init(void) 601{ 602 if (!MACHINE_IS_VM) { 603 MESSAGE_LOG(KERN_INFO, 604 "Machine is not VM: %s " 605 "discipline not initializing", 606 dasd_diag_discipline.name); 607 return -ENODEV; 608 } 609 ASCEBC(dasd_diag_discipline.ebcname, 4); 610 611 ctl_set_bit(0, 9); 612 register_external_interrupt(0x2603, dasd_ext_handler); 613 dasd_diag_discipline_pointer = &dasd_diag_discipline; 614 return 0; 615} 616 617static void __exit 618dasd_diag_cleanup(void) 619{ 620 unregister_external_interrupt(0x2603, dasd_ext_handler); 621 ctl_clear_bit(0, 9); 622 dasd_diag_discipline_pointer = NULL; 623} 624 625module_init(dasd_diag_init); 626module_exit(dasd_diag_cleanup); 627