1 /* 2 * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com> 3 * Horst Hummel <Horst.Hummel@de.ibm.com> 4 * Carsten Otte <Cotte@de.ibm.com> 5 * Martin Schwidefsky <schwidefsky@de.ibm.com> 6 * Bugreports.to..: <Linux390@de.ibm.com> 7 * Copyright IBM Corp. 1999, 2009 8 */ 9 10 #define KMSG_COMPONENT "dasd" 11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 12 13 #include <linux/kmod.h> 14 #include <linux/init.h> 15 #include <linux/interrupt.h> 16 #include <linux/ctype.h> 17 #include <linux/major.h> 18 #include <linux/slab.h> 19 #include <linux/hdreg.h> 20 #include <linux/async.h> 21 #include <linux/mutex.h> 22 #include <linux/debugfs.h> 23 #include <linux/seq_file.h> 24 #include <linux/vmalloc.h> 25 26 #include <asm/ccwdev.h> 27 #include <asm/ebcdic.h> 28 #include <asm/idals.h> 29 #include <asm/itcw.h> 30 #include <asm/diag.h> 31 32 /* This is ugly... */ 33 #define PRINTK_HEADER "dasd:" 34 35 #include "dasd_int.h" 36 /* 37 * SECTION: Constant definitions to be used within this file 38 */ 39 #define DASD_CHANQ_MAX_SIZE 4 40 41 #define DASD_DIAG_MOD "dasd_diag_mod" 42 43 /* 44 * SECTION: exported variables of dasd.c 45 */ 46 debug_info_t *dasd_debug_area; 47 EXPORT_SYMBOL(dasd_debug_area); 48 static struct dentry *dasd_debugfs_root_entry; 49 struct dasd_discipline *dasd_diag_discipline_pointer; 50 EXPORT_SYMBOL(dasd_diag_discipline_pointer); 51 void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *); 52 53 MODULE_AUTHOR("Holger Smolinski <Holger.Smolinski@de.ibm.com>"); 54 MODULE_DESCRIPTION("Linux on S/390 DASD device driver," 55 " Copyright IBM Corp. 2000"); 56 MODULE_SUPPORTED_DEVICE("dasd"); 57 MODULE_LICENSE("GPL"); 58 59 /* 60 * SECTION: prototypes for static functions of dasd.c 61 */ 62 static int dasd_alloc_queue(struct dasd_block *); 63 static void dasd_setup_queue(struct dasd_block *); 64 static void dasd_free_queue(struct dasd_block *); 65 static void dasd_flush_request_queue(struct dasd_block *); 66 static int dasd_flush_block_queue(struct dasd_block *); 67 static void dasd_device_tasklet(struct dasd_device *); 68 static void dasd_block_tasklet(struct dasd_block *); 69 static void do_kick_device(struct work_struct *); 70 static void do_restore_device(struct work_struct *); 71 static void do_reload_device(struct work_struct *); 72 static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *); 73 static void dasd_device_timeout(unsigned long); 74 static void dasd_block_timeout(unsigned long); 75 static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *); 76 static void dasd_profile_init(struct dasd_profile *, struct dentry *); 77 static void dasd_profile_exit(struct dasd_profile *); 78 79 /* 80 * SECTION: Operations on the device structure. 81 */ 82 static wait_queue_head_t dasd_init_waitq; 83 static wait_queue_head_t dasd_flush_wq; 84 static wait_queue_head_t generic_waitq; 85 static wait_queue_head_t shutdown_waitq; 86 87 /* 88 * Allocate memory for a new device structure. 89 */ 90 struct dasd_device *dasd_alloc_device(void) 91 { 92 struct dasd_device *device; 93 94 device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC); 95 if (!device) 96 return ERR_PTR(-ENOMEM); 97 98 /* Get two pages for normal block device operations. */ 99 device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1); 100 if (!device->ccw_mem) { 101 kfree(device); 102 return ERR_PTR(-ENOMEM); 103 } 104 /* Get one page for error recovery. */ 105 device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA); 106 if (!device->erp_mem) { 107 free_pages((unsigned long) device->ccw_mem, 1); 108 kfree(device); 109 return ERR_PTR(-ENOMEM); 110 } 111 112 dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2); 113 dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE); 114 spin_lock_init(&device->mem_lock); 115 atomic_set(&device->tasklet_scheduled, 0); 116 tasklet_init(&device->tasklet, 117 (void (*)(unsigned long)) dasd_device_tasklet, 118 (unsigned long) device); 119 INIT_LIST_HEAD(&device->ccw_queue); 120 init_timer(&device->timer); 121 device->timer.function = dasd_device_timeout; 122 device->timer.data = (unsigned long) device; 123 INIT_WORK(&device->kick_work, do_kick_device); 124 INIT_WORK(&device->restore_device, do_restore_device); 125 INIT_WORK(&device->reload_device, do_reload_device); 126 device->state = DASD_STATE_NEW; 127 device->target = DASD_STATE_NEW; 128 mutex_init(&device->state_mutex); 129 spin_lock_init(&device->profile.lock); 130 return device; 131 } 132 133 /* 134 * Free memory of a device structure. 135 */ 136 void dasd_free_device(struct dasd_device *device) 137 { 138 kfree(device->private); 139 free_page((unsigned long) device->erp_mem); 140 free_pages((unsigned long) device->ccw_mem, 1); 141 kfree(device); 142 } 143 144 /* 145 * Allocate memory for a new device structure. 146 */ 147 struct dasd_block *dasd_alloc_block(void) 148 { 149 struct dasd_block *block; 150 151 block = kzalloc(sizeof(*block), GFP_ATOMIC); 152 if (!block) 153 return ERR_PTR(-ENOMEM); 154 /* open_count = 0 means device online but not in use */ 155 atomic_set(&block->open_count, -1); 156 157 spin_lock_init(&block->request_queue_lock); 158 atomic_set(&block->tasklet_scheduled, 0); 159 tasklet_init(&block->tasklet, 160 (void (*)(unsigned long)) dasd_block_tasklet, 161 (unsigned long) block); 162 INIT_LIST_HEAD(&block->ccw_queue); 163 spin_lock_init(&block->queue_lock); 164 init_timer(&block->timer); 165 block->timer.function = dasd_block_timeout; 166 block->timer.data = (unsigned long) block; 167 spin_lock_init(&block->profile.lock); 168 169 return block; 170 } 171 EXPORT_SYMBOL_GPL(dasd_alloc_block); 172 173 /* 174 * Free memory of a device structure. 175 */ 176 void dasd_free_block(struct dasd_block *block) 177 { 178 kfree(block); 179 } 180 EXPORT_SYMBOL_GPL(dasd_free_block); 181 182 /* 183 * Make a new device known to the system. 184 */ 185 static int dasd_state_new_to_known(struct dasd_device *device) 186 { 187 int rc; 188 189 /* 190 * As long as the device is not in state DASD_STATE_NEW we want to 191 * keep the reference count > 0. 192 */ 193 dasd_get_device(device); 194 195 if (device->block) { 196 rc = dasd_alloc_queue(device->block); 197 if (rc) { 198 dasd_put_device(device); 199 return rc; 200 } 201 } 202 device->state = DASD_STATE_KNOWN; 203 return 0; 204 } 205 206 /* 207 * Let the system forget about a device. 208 */ 209 static int dasd_state_known_to_new(struct dasd_device *device) 210 { 211 /* Disable extended error reporting for this device. */ 212 dasd_eer_disable(device); 213 /* Forget the discipline information. */ 214 if (device->discipline) { 215 if (device->discipline->uncheck_device) 216 device->discipline->uncheck_device(device); 217 module_put(device->discipline->owner); 218 } 219 device->discipline = NULL; 220 if (device->base_discipline) 221 module_put(device->base_discipline->owner); 222 device->base_discipline = NULL; 223 device->state = DASD_STATE_NEW; 224 225 if (device->block) 226 dasd_free_queue(device->block); 227 228 /* Give up reference we took in dasd_state_new_to_known. */ 229 dasd_put_device(device); 230 return 0; 231 } 232 233 static struct dentry *dasd_debugfs_setup(const char *name, 234 struct dentry *base_dentry) 235 { 236 struct dentry *pde; 237 238 if (!base_dentry) 239 return NULL; 240 pde = debugfs_create_dir(name, base_dentry); 241 if (!pde || IS_ERR(pde)) 242 return NULL; 243 return pde; 244 } 245 246 /* 247 * Request the irq line for the device. 248 */ 249 static int dasd_state_known_to_basic(struct dasd_device *device) 250 { 251 struct dasd_block *block = device->block; 252 int rc = 0; 253 254 /* Allocate and register gendisk structure. */ 255 if (block) { 256 rc = dasd_gendisk_alloc(block); 257 if (rc) 258 return rc; 259 block->debugfs_dentry = 260 dasd_debugfs_setup(block->gdp->disk_name, 261 dasd_debugfs_root_entry); 262 dasd_profile_init(&block->profile, block->debugfs_dentry); 263 if (dasd_global_profile_level == DASD_PROFILE_ON) 264 dasd_profile_on(&device->block->profile); 265 } 266 device->debugfs_dentry = 267 dasd_debugfs_setup(dev_name(&device->cdev->dev), 268 dasd_debugfs_root_entry); 269 dasd_profile_init(&device->profile, device->debugfs_dentry); 270 271 /* register 'device' debug area, used for all DBF_DEV_XXX calls */ 272 device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1, 273 8 * sizeof(long)); 274 debug_register_view(device->debug_area, &debug_sprintf_view); 275 debug_set_level(device->debug_area, DBF_WARNING); 276 DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created"); 277 278 device->state = DASD_STATE_BASIC; 279 280 return rc; 281 } 282 283 /* 284 * Release the irq line for the device. Terminate any running i/o. 285 */ 286 static int dasd_state_basic_to_known(struct dasd_device *device) 287 { 288 int rc; 289 290 if (device->discipline->basic_to_known) { 291 rc = device->discipline->basic_to_known(device); 292 if (rc) 293 return rc; 294 } 295 296 if (device->block) { 297 dasd_profile_exit(&device->block->profile); 298 debugfs_remove(device->block->debugfs_dentry); 299 dasd_gendisk_free(device->block); 300 dasd_block_clear_timer(device->block); 301 } 302 rc = dasd_flush_device_queue(device); 303 if (rc) 304 return rc; 305 dasd_device_clear_timer(device); 306 dasd_profile_exit(&device->profile); 307 debugfs_remove(device->debugfs_dentry); 308 DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device); 309 if (device->debug_area != NULL) { 310 debug_unregister(device->debug_area); 311 device->debug_area = NULL; 312 } 313 device->state = DASD_STATE_KNOWN; 314 return 0; 315 } 316 317 /* 318 * Do the initial analysis. The do_analysis function may return 319 * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC 320 * until the discipline decides to continue the startup sequence 321 * by calling the function dasd_change_state. The eckd disciplines 322 * uses this to start a ccw that detects the format. The completion 323 * interrupt for this detection ccw uses the kernel event daemon to 324 * trigger the call to dasd_change_state. All this is done in the 325 * discipline code, see dasd_eckd.c. 326 * After the analysis ccw is done (do_analysis returned 0) the block 327 * device is setup. 328 * In case the analysis returns an error, the device setup is stopped 329 * (a fake disk was already added to allow formatting). 330 */ 331 static int dasd_state_basic_to_ready(struct dasd_device *device) 332 { 333 int rc; 334 struct dasd_block *block; 335 336 rc = 0; 337 block = device->block; 338 /* make disk known with correct capacity */ 339 if (block) { 340 if (block->base->discipline->do_analysis != NULL) 341 rc = block->base->discipline->do_analysis(block); 342 if (rc) { 343 if (rc != -EAGAIN) { 344 device->state = DASD_STATE_UNFMT; 345 goto out; 346 } 347 return rc; 348 } 349 dasd_setup_queue(block); 350 set_capacity(block->gdp, 351 block->blocks << block->s2b_shift); 352 device->state = DASD_STATE_READY; 353 rc = dasd_scan_partitions(block); 354 if (rc) { 355 device->state = DASD_STATE_BASIC; 356 return rc; 357 } 358 } else { 359 device->state = DASD_STATE_READY; 360 } 361 out: 362 if (device->discipline->basic_to_ready) 363 rc = device->discipline->basic_to_ready(device); 364 return rc; 365 } 366 367 static inline 368 int _wait_for_empty_queues(struct dasd_device *device) 369 { 370 if (device->block) 371 return list_empty(&device->ccw_queue) && 372 list_empty(&device->block->ccw_queue); 373 else 374 return list_empty(&device->ccw_queue); 375 } 376 377 /* 378 * Remove device from block device layer. Destroy dirty buffers. 379 * Forget format information. Check if the target level is basic 380 * and if it is create fake disk for formatting. 381 */ 382 static int dasd_state_ready_to_basic(struct dasd_device *device) 383 { 384 int rc; 385 386 device->state = DASD_STATE_BASIC; 387 if (device->block) { 388 struct dasd_block *block = device->block; 389 rc = dasd_flush_block_queue(block); 390 if (rc) { 391 device->state = DASD_STATE_READY; 392 return rc; 393 } 394 dasd_flush_request_queue(block); 395 dasd_destroy_partitions(block); 396 block->blocks = 0; 397 block->bp_block = 0; 398 block->s2b_shift = 0; 399 } 400 return 0; 401 } 402 403 /* 404 * Back to basic. 405 */ 406 static int dasd_state_unfmt_to_basic(struct dasd_device *device) 407 { 408 device->state = DASD_STATE_BASIC; 409 return 0; 410 } 411 412 /* 413 * Make the device online and schedule the bottom half to start 414 * the requeueing of requests from the linux request queue to the 415 * ccw queue. 416 */ 417 static int 418 dasd_state_ready_to_online(struct dasd_device * device) 419 { 420 struct gendisk *disk; 421 struct disk_part_iter piter; 422 struct hd_struct *part; 423 424 device->state = DASD_STATE_ONLINE; 425 if (device->block) { 426 dasd_schedule_block_bh(device->block); 427 if ((device->features & DASD_FEATURE_USERAW)) { 428 disk = device->block->gdp; 429 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); 430 return 0; 431 } 432 disk = device->block->bdev->bd_disk; 433 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0); 434 while ((part = disk_part_iter_next(&piter))) 435 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE); 436 disk_part_iter_exit(&piter); 437 } 438 return 0; 439 } 440 441 /* 442 * Stop the requeueing of requests again. 443 */ 444 static int dasd_state_online_to_ready(struct dasd_device *device) 445 { 446 int rc; 447 struct gendisk *disk; 448 struct disk_part_iter piter; 449 struct hd_struct *part; 450 451 if (device->discipline->online_to_ready) { 452 rc = device->discipline->online_to_ready(device); 453 if (rc) 454 return rc; 455 } 456 457 device->state = DASD_STATE_READY; 458 if (device->block && !(device->features & DASD_FEATURE_USERAW)) { 459 disk = device->block->bdev->bd_disk; 460 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0); 461 while ((part = disk_part_iter_next(&piter))) 462 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE); 463 disk_part_iter_exit(&piter); 464 } 465 return 0; 466 } 467 468 /* 469 * Device startup state changes. 470 */ 471 static int dasd_increase_state(struct dasd_device *device) 472 { 473 int rc; 474 475 rc = 0; 476 if (device->state == DASD_STATE_NEW && 477 device->target >= DASD_STATE_KNOWN) 478 rc = dasd_state_new_to_known(device); 479 480 if (!rc && 481 device->state == DASD_STATE_KNOWN && 482 device->target >= DASD_STATE_BASIC) 483 rc = dasd_state_known_to_basic(device); 484 485 if (!rc && 486 device->state == DASD_STATE_BASIC && 487 device->target >= DASD_STATE_READY) 488 rc = dasd_state_basic_to_ready(device); 489 490 if (!rc && 491 device->state == DASD_STATE_UNFMT && 492 device->target > DASD_STATE_UNFMT) 493 rc = -EPERM; 494 495 if (!rc && 496 device->state == DASD_STATE_READY && 497 device->target >= DASD_STATE_ONLINE) 498 rc = dasd_state_ready_to_online(device); 499 500 return rc; 501 } 502 503 /* 504 * Device shutdown state changes. 505 */ 506 static int dasd_decrease_state(struct dasd_device *device) 507 { 508 int rc; 509 510 rc = 0; 511 if (device->state == DASD_STATE_ONLINE && 512 device->target <= DASD_STATE_READY) 513 rc = dasd_state_online_to_ready(device); 514 515 if (!rc && 516 device->state == DASD_STATE_READY && 517 device->target <= DASD_STATE_BASIC) 518 rc = dasd_state_ready_to_basic(device); 519 520 if (!rc && 521 device->state == DASD_STATE_UNFMT && 522 device->target <= DASD_STATE_BASIC) 523 rc = dasd_state_unfmt_to_basic(device); 524 525 if (!rc && 526 device->state == DASD_STATE_BASIC && 527 device->target <= DASD_STATE_KNOWN) 528 rc = dasd_state_basic_to_known(device); 529 530 if (!rc && 531 device->state == DASD_STATE_KNOWN && 532 device->target <= DASD_STATE_NEW) 533 rc = dasd_state_known_to_new(device); 534 535 return rc; 536 } 537 538 /* 539 * This is the main startup/shutdown routine. 540 */ 541 static void dasd_change_state(struct dasd_device *device) 542 { 543 int rc; 544 545 if (device->state == device->target) 546 /* Already where we want to go today... */ 547 return; 548 if (device->state < device->target) 549 rc = dasd_increase_state(device); 550 else 551 rc = dasd_decrease_state(device); 552 if (rc == -EAGAIN) 553 return; 554 if (rc) 555 device->target = device->state; 556 557 /* let user-space know that the device status changed */ 558 kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE); 559 560 if (device->state == device->target) 561 wake_up(&dasd_init_waitq); 562 } 563 564 /* 565 * Kick starter for devices that did not complete the startup/shutdown 566 * procedure or were sleeping because of a pending state. 567 * dasd_kick_device will schedule a call do do_kick_device to the kernel 568 * event daemon. 569 */ 570 static void do_kick_device(struct work_struct *work) 571 { 572 struct dasd_device *device = container_of(work, struct dasd_device, kick_work); 573 mutex_lock(&device->state_mutex); 574 dasd_change_state(device); 575 mutex_unlock(&device->state_mutex); 576 dasd_schedule_device_bh(device); 577 dasd_put_device(device); 578 } 579 580 void dasd_kick_device(struct dasd_device *device) 581 { 582 dasd_get_device(device); 583 /* queue call to dasd_kick_device to the kernel event daemon. */ 584 if (!schedule_work(&device->kick_work)) 585 dasd_put_device(device); 586 } 587 EXPORT_SYMBOL(dasd_kick_device); 588 589 /* 590 * dasd_reload_device will schedule a call do do_reload_device to the kernel 591 * event daemon. 592 */ 593 static void do_reload_device(struct work_struct *work) 594 { 595 struct dasd_device *device = container_of(work, struct dasd_device, 596 reload_device); 597 device->discipline->reload(device); 598 dasd_put_device(device); 599 } 600 601 void dasd_reload_device(struct dasd_device *device) 602 { 603 dasd_get_device(device); 604 /* queue call to dasd_reload_device to the kernel event daemon. */ 605 if (!schedule_work(&device->reload_device)) 606 dasd_put_device(device); 607 } 608 EXPORT_SYMBOL(dasd_reload_device); 609 610 /* 611 * dasd_restore_device will schedule a call do do_restore_device to the kernel 612 * event daemon. 613 */ 614 static void do_restore_device(struct work_struct *work) 615 { 616 struct dasd_device *device = container_of(work, struct dasd_device, 617 restore_device); 618 device->cdev->drv->restore(device->cdev); 619 dasd_put_device(device); 620 } 621 622 void dasd_restore_device(struct dasd_device *device) 623 { 624 dasd_get_device(device); 625 /* queue call to dasd_restore_device to the kernel event daemon. */ 626 if (!schedule_work(&device->restore_device)) 627 dasd_put_device(device); 628 } 629 630 /* 631 * Set the target state for a device and starts the state change. 632 */ 633 void dasd_set_target_state(struct dasd_device *device, int target) 634 { 635 dasd_get_device(device); 636 mutex_lock(&device->state_mutex); 637 /* If we are in probeonly mode stop at DASD_STATE_READY. */ 638 if (dasd_probeonly && target > DASD_STATE_READY) 639 target = DASD_STATE_READY; 640 if (device->target != target) { 641 if (device->state == target) 642 wake_up(&dasd_init_waitq); 643 device->target = target; 644 } 645 if (device->state != device->target) 646 dasd_change_state(device); 647 mutex_unlock(&device->state_mutex); 648 dasd_put_device(device); 649 } 650 EXPORT_SYMBOL(dasd_set_target_state); 651 652 /* 653 * Enable devices with device numbers in [from..to]. 654 */ 655 static inline int _wait_for_device(struct dasd_device *device) 656 { 657 return (device->state == device->target); 658 } 659 660 void dasd_enable_device(struct dasd_device *device) 661 { 662 dasd_set_target_state(device, DASD_STATE_ONLINE); 663 if (device->state <= DASD_STATE_KNOWN) 664 /* No discipline for device found. */ 665 dasd_set_target_state(device, DASD_STATE_NEW); 666 /* Now wait for the devices to come up. */ 667 wait_event(dasd_init_waitq, _wait_for_device(device)); 668 669 dasd_reload_device(device); 670 if (device->discipline->kick_validate) 671 device->discipline->kick_validate(device); 672 } 673 EXPORT_SYMBOL(dasd_enable_device); 674 675 /* 676 * SECTION: device operation (interrupt handler, start i/o, term i/o ...) 677 */ 678 679 unsigned int dasd_global_profile_level = DASD_PROFILE_OFF; 680 681 #ifdef CONFIG_DASD_PROFILE 682 struct dasd_profile dasd_global_profile = { 683 .lock = __SPIN_LOCK_UNLOCKED(dasd_global_profile.lock), 684 }; 685 static struct dentry *dasd_debugfs_global_entry; 686 687 /* 688 * Add profiling information for cqr before execution. 689 */ 690 static void dasd_profile_start(struct dasd_block *block, 691 struct dasd_ccw_req *cqr, 692 struct request *req) 693 { 694 struct list_head *l; 695 unsigned int counter; 696 struct dasd_device *device; 697 698 /* count the length of the chanq for statistics */ 699 counter = 0; 700 if (dasd_global_profile_level || block->profile.data) 701 list_for_each(l, &block->ccw_queue) 702 if (++counter >= 31) 703 break; 704 705 spin_lock(&dasd_global_profile.lock); 706 if (dasd_global_profile.data) { 707 dasd_global_profile.data->dasd_io_nr_req[counter]++; 708 if (rq_data_dir(req) == READ) 709 dasd_global_profile.data->dasd_read_nr_req[counter]++; 710 } 711 spin_unlock(&dasd_global_profile.lock); 712 713 spin_lock(&block->profile.lock); 714 if (block->profile.data) { 715 block->profile.data->dasd_io_nr_req[counter]++; 716 if (rq_data_dir(req) == READ) 717 block->profile.data->dasd_read_nr_req[counter]++; 718 } 719 spin_unlock(&block->profile.lock); 720 721 /* 722 * We count the request for the start device, even though it may run on 723 * some other device due to error recovery. This way we make sure that 724 * we count each request only once. 725 */ 726 device = cqr->startdev; 727 if (device->profile.data) { 728 counter = 1; /* request is not yet queued on the start device */ 729 list_for_each(l, &device->ccw_queue) 730 if (++counter >= 31) 731 break; 732 } 733 spin_lock(&device->profile.lock); 734 if (device->profile.data) { 735 device->profile.data->dasd_io_nr_req[counter]++; 736 if (rq_data_dir(req) == READ) 737 device->profile.data->dasd_read_nr_req[counter]++; 738 } 739 spin_unlock(&device->profile.lock); 740 } 741 742 /* 743 * Add profiling information for cqr after execution. 744 */ 745 746 #define dasd_profile_counter(value, index) \ 747 { \ 748 for (index = 0; index < 31 && value >> (2+index); index++) \ 749 ; \ 750 } 751 752 static void dasd_profile_end_add_data(struct dasd_profile_info *data, 753 int is_alias, 754 int is_tpm, 755 int is_read, 756 long sectors, 757 int sectors_ind, 758 int tottime_ind, 759 int tottimeps_ind, 760 int strtime_ind, 761 int irqtime_ind, 762 int irqtimeps_ind, 763 int endtime_ind) 764 { 765 /* in case of an overflow, reset the whole profile */ 766 if (data->dasd_io_reqs == UINT_MAX) { 767 memset(data, 0, sizeof(*data)); 768 getnstimeofday(&data->starttod); 769 } 770 data->dasd_io_reqs++; 771 data->dasd_io_sects += sectors; 772 if (is_alias) 773 data->dasd_io_alias++; 774 if (is_tpm) 775 data->dasd_io_tpm++; 776 777 data->dasd_io_secs[sectors_ind]++; 778 data->dasd_io_times[tottime_ind]++; 779 data->dasd_io_timps[tottimeps_ind]++; 780 data->dasd_io_time1[strtime_ind]++; 781 data->dasd_io_time2[irqtime_ind]++; 782 data->dasd_io_time2ps[irqtimeps_ind]++; 783 data->dasd_io_time3[endtime_ind]++; 784 785 if (is_read) { 786 data->dasd_read_reqs++; 787 data->dasd_read_sects += sectors; 788 if (is_alias) 789 data->dasd_read_alias++; 790 if (is_tpm) 791 data->dasd_read_tpm++; 792 data->dasd_read_secs[sectors_ind]++; 793 data->dasd_read_times[tottime_ind]++; 794 data->dasd_read_time1[strtime_ind]++; 795 data->dasd_read_time2[irqtime_ind]++; 796 data->dasd_read_time3[endtime_ind]++; 797 } 798 } 799 800 static void dasd_profile_end(struct dasd_block *block, 801 struct dasd_ccw_req *cqr, 802 struct request *req) 803 { 804 long strtime, irqtime, endtime, tottime; /* in microseconds */ 805 long tottimeps, sectors; 806 struct dasd_device *device; 807 int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind; 808 int irqtime_ind, irqtimeps_ind, endtime_ind; 809 810 device = cqr->startdev; 811 if (!(dasd_global_profile_level || 812 block->profile.data || 813 device->profile.data)) 814 return; 815 816 sectors = blk_rq_sectors(req); 817 if (!cqr->buildclk || !cqr->startclk || 818 !cqr->stopclk || !cqr->endclk || 819 !sectors) 820 return; 821 822 strtime = ((cqr->startclk - cqr->buildclk) >> 12); 823 irqtime = ((cqr->stopclk - cqr->startclk) >> 12); 824 endtime = ((cqr->endclk - cqr->stopclk) >> 12); 825 tottime = ((cqr->endclk - cqr->buildclk) >> 12); 826 tottimeps = tottime / sectors; 827 828 dasd_profile_counter(sectors, sectors_ind); 829 dasd_profile_counter(tottime, tottime_ind); 830 dasd_profile_counter(tottimeps, tottimeps_ind); 831 dasd_profile_counter(strtime, strtime_ind); 832 dasd_profile_counter(irqtime, irqtime_ind); 833 dasd_profile_counter(irqtime / sectors, irqtimeps_ind); 834 dasd_profile_counter(endtime, endtime_ind); 835 836 spin_lock(&dasd_global_profile.lock); 837 if (dasd_global_profile.data) { 838 dasd_profile_end_add_data(dasd_global_profile.data, 839 cqr->startdev != block->base, 840 cqr->cpmode == 1, 841 rq_data_dir(req) == READ, 842 sectors, sectors_ind, tottime_ind, 843 tottimeps_ind, strtime_ind, 844 irqtime_ind, irqtimeps_ind, 845 endtime_ind); 846 } 847 spin_unlock(&dasd_global_profile.lock); 848 849 spin_lock(&block->profile.lock); 850 if (block->profile.data) 851 dasd_profile_end_add_data(block->profile.data, 852 cqr->startdev != block->base, 853 cqr->cpmode == 1, 854 rq_data_dir(req) == READ, 855 sectors, sectors_ind, tottime_ind, 856 tottimeps_ind, strtime_ind, 857 irqtime_ind, irqtimeps_ind, 858 endtime_ind); 859 spin_unlock(&block->profile.lock); 860 861 spin_lock(&device->profile.lock); 862 if (device->profile.data) 863 dasd_profile_end_add_data(device->profile.data, 864 cqr->startdev != block->base, 865 cqr->cpmode == 1, 866 rq_data_dir(req) == READ, 867 sectors, sectors_ind, tottime_ind, 868 tottimeps_ind, strtime_ind, 869 irqtime_ind, irqtimeps_ind, 870 endtime_ind); 871 spin_unlock(&device->profile.lock); 872 } 873 874 void dasd_profile_reset(struct dasd_profile *profile) 875 { 876 struct dasd_profile_info *data; 877 878 spin_lock_bh(&profile->lock); 879 data = profile->data; 880 if (!data) { 881 spin_unlock_bh(&profile->lock); 882 return; 883 } 884 memset(data, 0, sizeof(*data)); 885 getnstimeofday(&data->starttod); 886 spin_unlock_bh(&profile->lock); 887 } 888 889 int dasd_profile_on(struct dasd_profile *profile) 890 { 891 struct dasd_profile_info *data; 892 893 data = kzalloc(sizeof(*data), GFP_KERNEL); 894 if (!data) 895 return -ENOMEM; 896 spin_lock_bh(&profile->lock); 897 if (profile->data) { 898 spin_unlock_bh(&profile->lock); 899 kfree(data); 900 return 0; 901 } 902 getnstimeofday(&data->starttod); 903 profile->data = data; 904 spin_unlock_bh(&profile->lock); 905 return 0; 906 } 907 908 void dasd_profile_off(struct dasd_profile *profile) 909 { 910 spin_lock_bh(&profile->lock); 911 kfree(profile->data); 912 profile->data = NULL; 913 spin_unlock_bh(&profile->lock); 914 } 915 916 char *dasd_get_user_string(const char __user *user_buf, size_t user_len) 917 { 918 char *buffer; 919 920 buffer = vmalloc(user_len + 1); 921 if (buffer == NULL) 922 return ERR_PTR(-ENOMEM); 923 if (copy_from_user(buffer, user_buf, user_len) != 0) { 924 vfree(buffer); 925 return ERR_PTR(-EFAULT); 926 } 927 /* got the string, now strip linefeed. */ 928 if (buffer[user_len - 1] == '\n') 929 buffer[user_len - 1] = 0; 930 else 931 buffer[user_len] = 0; 932 return buffer; 933 } 934 935 static ssize_t dasd_stats_write(struct file *file, 936 const char __user *user_buf, 937 size_t user_len, loff_t *pos) 938 { 939 char *buffer, *str; 940 int rc; 941 struct seq_file *m = (struct seq_file *)file->private_data; 942 struct dasd_profile *prof = m->private; 943 944 if (user_len > 65536) 945 user_len = 65536; 946 buffer = dasd_get_user_string(user_buf, user_len); 947 if (IS_ERR(buffer)) 948 return PTR_ERR(buffer); 949 950 str = skip_spaces(buffer); 951 rc = user_len; 952 if (strncmp(str, "reset", 5) == 0) { 953 dasd_profile_reset(prof); 954 } else if (strncmp(str, "on", 2) == 0) { 955 rc = dasd_profile_on(prof); 956 if (rc) 957 goto out; 958 rc = user_len; 959 if (prof == &dasd_global_profile) { 960 dasd_profile_reset(prof); 961 dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY; 962 } 963 } else if (strncmp(str, "off", 3) == 0) { 964 if (prof == &dasd_global_profile) 965 dasd_global_profile_level = DASD_PROFILE_OFF; 966 dasd_profile_off(prof); 967 } else 968 rc = -EINVAL; 969 out: 970 vfree(buffer); 971 return rc; 972 } 973 974 static void dasd_stats_array(struct seq_file *m, unsigned int *array) 975 { 976 int i; 977 978 for (i = 0; i < 32; i++) 979 seq_printf(m, "%u ", array[i]); 980 seq_putc(m, '\n'); 981 } 982 983 static void dasd_stats_seq_print(struct seq_file *m, 984 struct dasd_profile_info *data) 985 { 986 seq_printf(m, "start_time %ld.%09ld\n", 987 data->starttod.tv_sec, data->starttod.tv_nsec); 988 seq_printf(m, "total_requests %u\n", data->dasd_io_reqs); 989 seq_printf(m, "total_sectors %u\n", data->dasd_io_sects); 990 seq_printf(m, "total_pav %u\n", data->dasd_io_alias); 991 seq_printf(m, "total_hpf %u\n", data->dasd_io_tpm); 992 seq_puts(m, "histogram_sectors "); 993 dasd_stats_array(m, data->dasd_io_secs); 994 seq_puts(m, "histogram_io_times "); 995 dasd_stats_array(m, data->dasd_io_times); 996 seq_puts(m, "histogram_io_times_weighted "); 997 dasd_stats_array(m, data->dasd_io_timps); 998 seq_puts(m, "histogram_time_build_to_ssch "); 999 dasd_stats_array(m, data->dasd_io_time1); 1000 seq_puts(m, "histogram_time_ssch_to_irq "); 1001 dasd_stats_array(m, data->dasd_io_time2); 1002 seq_puts(m, "histogram_time_ssch_to_irq_weighted "); 1003 dasd_stats_array(m, data->dasd_io_time2ps); 1004 seq_puts(m, "histogram_time_irq_to_end "); 1005 dasd_stats_array(m, data->dasd_io_time3); 1006 seq_puts(m, "histogram_ccw_queue_length "); 1007 dasd_stats_array(m, data->dasd_io_nr_req); 1008 seq_printf(m, "total_read_requests %u\n", data->dasd_read_reqs); 1009 seq_printf(m, "total_read_sectors %u\n", data->dasd_read_sects); 1010 seq_printf(m, "total_read_pav %u\n", data->dasd_read_alias); 1011 seq_printf(m, "total_read_hpf %u\n", data->dasd_read_tpm); 1012 seq_puts(m, "histogram_read_sectors "); 1013 dasd_stats_array(m, data->dasd_read_secs); 1014 seq_puts(m, "histogram_read_times "); 1015 dasd_stats_array(m, data->dasd_read_times); 1016 seq_puts(m, "histogram_read_time_build_to_ssch "); 1017 dasd_stats_array(m, data->dasd_read_time1); 1018 seq_puts(m, "histogram_read_time_ssch_to_irq "); 1019 dasd_stats_array(m, data->dasd_read_time2); 1020 seq_puts(m, "histogram_read_time_irq_to_end "); 1021 dasd_stats_array(m, data->dasd_read_time3); 1022 seq_puts(m, "histogram_read_ccw_queue_length "); 1023 dasd_stats_array(m, data->dasd_read_nr_req); 1024 } 1025 1026 static int dasd_stats_show(struct seq_file *m, void *v) 1027 { 1028 struct dasd_profile *profile; 1029 struct dasd_profile_info *data; 1030 1031 profile = m->private; 1032 spin_lock_bh(&profile->lock); 1033 data = profile->data; 1034 if (!data) { 1035 spin_unlock_bh(&profile->lock); 1036 seq_puts(m, "disabled\n"); 1037 return 0; 1038 } 1039 dasd_stats_seq_print(m, data); 1040 spin_unlock_bh(&profile->lock); 1041 return 0; 1042 } 1043 1044 static int dasd_stats_open(struct inode *inode, struct file *file) 1045 { 1046 struct dasd_profile *profile = inode->i_private; 1047 return single_open(file, dasd_stats_show, profile); 1048 } 1049 1050 static const struct file_operations dasd_stats_raw_fops = { 1051 .owner = THIS_MODULE, 1052 .open = dasd_stats_open, 1053 .read = seq_read, 1054 .llseek = seq_lseek, 1055 .release = single_release, 1056 .write = dasd_stats_write, 1057 }; 1058 1059 static void dasd_profile_init(struct dasd_profile *profile, 1060 struct dentry *base_dentry) 1061 { 1062 umode_t mode; 1063 struct dentry *pde; 1064 1065 if (!base_dentry) 1066 return; 1067 profile->dentry = NULL; 1068 profile->data = NULL; 1069 mode = (S_IRUSR | S_IWUSR | S_IFREG); 1070 pde = debugfs_create_file("statistics", mode, base_dentry, 1071 profile, &dasd_stats_raw_fops); 1072 if (pde && !IS_ERR(pde)) 1073 profile->dentry = pde; 1074 return; 1075 } 1076 1077 static void dasd_profile_exit(struct dasd_profile *profile) 1078 { 1079 dasd_profile_off(profile); 1080 debugfs_remove(profile->dentry); 1081 profile->dentry = NULL; 1082 } 1083 1084 static void dasd_statistics_removeroot(void) 1085 { 1086 dasd_global_profile_level = DASD_PROFILE_OFF; 1087 dasd_profile_exit(&dasd_global_profile); 1088 debugfs_remove(dasd_debugfs_global_entry); 1089 debugfs_remove(dasd_debugfs_root_entry); 1090 } 1091 1092 static void dasd_statistics_createroot(void) 1093 { 1094 struct dentry *pde; 1095 1096 dasd_debugfs_root_entry = NULL; 1097 pde = debugfs_create_dir("dasd", NULL); 1098 if (!pde || IS_ERR(pde)) 1099 goto error; 1100 dasd_debugfs_root_entry = pde; 1101 pde = debugfs_create_dir("global", dasd_debugfs_root_entry); 1102 if (!pde || IS_ERR(pde)) 1103 goto error; 1104 dasd_debugfs_global_entry = pde; 1105 dasd_profile_init(&dasd_global_profile, dasd_debugfs_global_entry); 1106 return; 1107 1108 error: 1109 DBF_EVENT(DBF_ERR, "%s", 1110 "Creation of the dasd debugfs interface failed"); 1111 dasd_statistics_removeroot(); 1112 return; 1113 } 1114 1115 #else 1116 #define dasd_profile_start(block, cqr, req) do {} while (0) 1117 #define dasd_profile_end(block, cqr, req) do {} while (0) 1118 1119 static void dasd_statistics_createroot(void) 1120 { 1121 return; 1122 } 1123 1124 static void dasd_statistics_removeroot(void) 1125 { 1126 return; 1127 } 1128 1129 int dasd_stats_generic_show(struct seq_file *m, void *v) 1130 { 1131 seq_puts(m, "Statistics are not activated in this kernel\n"); 1132 return 0; 1133 } 1134 1135 static void dasd_profile_init(struct dasd_profile *profile, 1136 struct dentry *base_dentry) 1137 { 1138 return; 1139 } 1140 1141 static void dasd_profile_exit(struct dasd_profile *profile) 1142 { 1143 return; 1144 } 1145 1146 int dasd_profile_on(struct dasd_profile *profile) 1147 { 1148 return 0; 1149 } 1150 1151 #endif /* CONFIG_DASD_PROFILE */ 1152 1153 /* 1154 * Allocate memory for a channel program with 'cplength' channel 1155 * command words and 'datasize' additional space. There are two 1156 * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed 1157 * memory and 2) dasd_smalloc_request uses the static ccw memory 1158 * that gets allocated for each device. 1159 */ 1160 struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength, 1161 int datasize, 1162 struct dasd_device *device) 1163 { 1164 struct dasd_ccw_req *cqr; 1165 1166 /* Sanity checks */ 1167 BUG_ON(datasize > PAGE_SIZE || 1168 (cplength*sizeof(struct ccw1)) > PAGE_SIZE); 1169 1170 cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC); 1171 if (cqr == NULL) 1172 return ERR_PTR(-ENOMEM); 1173 cqr->cpaddr = NULL; 1174 if (cplength > 0) { 1175 cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1), 1176 GFP_ATOMIC | GFP_DMA); 1177 if (cqr->cpaddr == NULL) { 1178 kfree(cqr); 1179 return ERR_PTR(-ENOMEM); 1180 } 1181 } 1182 cqr->data = NULL; 1183 if (datasize > 0) { 1184 cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA); 1185 if (cqr->data == NULL) { 1186 kfree(cqr->cpaddr); 1187 kfree(cqr); 1188 return ERR_PTR(-ENOMEM); 1189 } 1190 } 1191 cqr->magic = magic; 1192 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); 1193 dasd_get_device(device); 1194 return cqr; 1195 } 1196 EXPORT_SYMBOL(dasd_kmalloc_request); 1197 1198 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength, 1199 int datasize, 1200 struct dasd_device *device) 1201 { 1202 unsigned long flags; 1203 struct dasd_ccw_req *cqr; 1204 char *data; 1205 int size; 1206 1207 size = (sizeof(struct dasd_ccw_req) + 7L) & -8L; 1208 if (cplength > 0) 1209 size += cplength * sizeof(struct ccw1); 1210 if (datasize > 0) 1211 size += datasize; 1212 spin_lock_irqsave(&device->mem_lock, flags); 1213 cqr = (struct dasd_ccw_req *) 1214 dasd_alloc_chunk(&device->ccw_chunks, size); 1215 spin_unlock_irqrestore(&device->mem_lock, flags); 1216 if (cqr == NULL) 1217 return ERR_PTR(-ENOMEM); 1218 memset(cqr, 0, sizeof(struct dasd_ccw_req)); 1219 data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L); 1220 cqr->cpaddr = NULL; 1221 if (cplength > 0) { 1222 cqr->cpaddr = (struct ccw1 *) data; 1223 data += cplength*sizeof(struct ccw1); 1224 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1)); 1225 } 1226 cqr->data = NULL; 1227 if (datasize > 0) { 1228 cqr->data = data; 1229 memset(cqr->data, 0, datasize); 1230 } 1231 cqr->magic = magic; 1232 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); 1233 dasd_get_device(device); 1234 return cqr; 1235 } 1236 EXPORT_SYMBOL(dasd_smalloc_request); 1237 1238 /* 1239 * Free memory of a channel program. This function needs to free all the 1240 * idal lists that might have been created by dasd_set_cda and the 1241 * struct dasd_ccw_req itself. 1242 */ 1243 void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device) 1244 { 1245 struct ccw1 *ccw; 1246 1247 /* Clear any idals used for the request. */ 1248 ccw = cqr->cpaddr; 1249 do { 1250 clear_normalized_cda(ccw); 1251 } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC)); 1252 kfree(cqr->cpaddr); 1253 kfree(cqr->data); 1254 kfree(cqr); 1255 dasd_put_device(device); 1256 } 1257 EXPORT_SYMBOL(dasd_kfree_request); 1258 1259 void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device) 1260 { 1261 unsigned long flags; 1262 1263 spin_lock_irqsave(&device->mem_lock, flags); 1264 dasd_free_chunk(&device->ccw_chunks, cqr); 1265 spin_unlock_irqrestore(&device->mem_lock, flags); 1266 dasd_put_device(device); 1267 } 1268 EXPORT_SYMBOL(dasd_sfree_request); 1269 1270 /* 1271 * Check discipline magic in cqr. 1272 */ 1273 static inline int dasd_check_cqr(struct dasd_ccw_req *cqr) 1274 { 1275 struct dasd_device *device; 1276 1277 if (cqr == NULL) 1278 return -EINVAL; 1279 device = cqr->startdev; 1280 if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) { 1281 DBF_DEV_EVENT(DBF_WARNING, device, 1282 " dasd_ccw_req 0x%08x magic doesn't match" 1283 " discipline 0x%08x", 1284 cqr->magic, 1285 *(unsigned int *) device->discipline->name); 1286 return -EINVAL; 1287 } 1288 return 0; 1289 } 1290 1291 /* 1292 * Terminate the current i/o and set the request to clear_pending. 1293 * Timer keeps device runnig. 1294 * ccw_device_clear can fail if the i/o subsystem 1295 * is in a bad mood. 1296 */ 1297 int dasd_term_IO(struct dasd_ccw_req *cqr) 1298 { 1299 struct dasd_device *device; 1300 int retries, rc; 1301 char errorstring[ERRORLENGTH]; 1302 1303 /* Check the cqr */ 1304 rc = dasd_check_cqr(cqr); 1305 if (rc) 1306 return rc; 1307 retries = 0; 1308 device = (struct dasd_device *) cqr->startdev; 1309 while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) { 1310 rc = ccw_device_clear(device->cdev, (long) cqr); 1311 switch (rc) { 1312 case 0: /* termination successful */ 1313 cqr->status = DASD_CQR_CLEAR_PENDING; 1314 cqr->stopclk = get_tod_clock(); 1315 cqr->starttime = 0; 1316 DBF_DEV_EVENT(DBF_DEBUG, device, 1317 "terminate cqr %p successful", 1318 cqr); 1319 break; 1320 case -ENODEV: 1321 DBF_DEV_EVENT(DBF_ERR, device, "%s", 1322 "device gone, retry"); 1323 break; 1324 case -EIO: 1325 DBF_DEV_EVENT(DBF_ERR, device, "%s", 1326 "I/O error, retry"); 1327 break; 1328 case -EINVAL: 1329 /* 1330 * device not valid so no I/O could be running 1331 * handle CQR as termination successful 1332 */ 1333 cqr->status = DASD_CQR_CLEARED; 1334 cqr->stopclk = get_tod_clock(); 1335 cqr->starttime = 0; 1336 /* no retries for invalid devices */ 1337 cqr->retries = -1; 1338 DBF_DEV_EVENT(DBF_ERR, device, "%s", 1339 "EINVAL, handle as terminated"); 1340 /* fake rc to success */ 1341 rc = 0; 1342 break; 1343 case -EBUSY: 1344 DBF_DEV_EVENT(DBF_ERR, device, "%s", 1345 "device busy, retry later"); 1346 break; 1347 default: 1348 /* internal error 10 - unknown rc*/ 1349 snprintf(errorstring, ERRORLENGTH, "10 %d", rc); 1350 dev_err(&device->cdev->dev, "An error occurred in the " 1351 "DASD device driver, reason=%s\n", errorstring); 1352 BUG(); 1353 break; 1354 } 1355 retries++; 1356 } 1357 dasd_schedule_device_bh(device); 1358 return rc; 1359 } 1360 EXPORT_SYMBOL(dasd_term_IO); 1361 1362 /* 1363 * Start the i/o. This start_IO can fail if the channel is really busy. 1364 * In that case set up a timer to start the request later. 1365 */ 1366 int dasd_start_IO(struct dasd_ccw_req *cqr) 1367 { 1368 struct dasd_device *device; 1369 int rc; 1370 char errorstring[ERRORLENGTH]; 1371 1372 /* Check the cqr */ 1373 rc = dasd_check_cqr(cqr); 1374 if (rc) { 1375 cqr->intrc = rc; 1376 return rc; 1377 } 1378 device = (struct dasd_device *) cqr->startdev; 1379 if (((cqr->block && 1380 test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) || 1381 test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) && 1382 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { 1383 DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p " 1384 "because of stolen lock", cqr); 1385 cqr->status = DASD_CQR_ERROR; 1386 cqr->intrc = -EPERM; 1387 return -EPERM; 1388 } 1389 if (cqr->retries < 0) { 1390 /* internal error 14 - start_IO run out of retries */ 1391 sprintf(errorstring, "14 %p", cqr); 1392 dev_err(&device->cdev->dev, "An error occurred in the DASD " 1393 "device driver, reason=%s\n", errorstring); 1394 cqr->status = DASD_CQR_ERROR; 1395 return -EIO; 1396 } 1397 cqr->startclk = get_tod_clock(); 1398 cqr->starttime = jiffies; 1399 cqr->retries--; 1400 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) { 1401 cqr->lpm &= device->path_data.opm; 1402 if (!cqr->lpm) 1403 cqr->lpm = device->path_data.opm; 1404 } 1405 if (cqr->cpmode == 1) { 1406 rc = ccw_device_tm_start(device->cdev, cqr->cpaddr, 1407 (long) cqr, cqr->lpm); 1408 } else { 1409 rc = ccw_device_start(device->cdev, cqr->cpaddr, 1410 (long) cqr, cqr->lpm, 0); 1411 } 1412 switch (rc) { 1413 case 0: 1414 cqr->status = DASD_CQR_IN_IO; 1415 break; 1416 case -EBUSY: 1417 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1418 "start_IO: device busy, retry later"); 1419 break; 1420 case -ETIMEDOUT: 1421 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1422 "start_IO: request timeout, retry later"); 1423 break; 1424 case -EACCES: 1425 /* -EACCES indicates that the request used only a subset of the 1426 * available paths and all these paths are gone. If the lpm of 1427 * this request was only a subset of the opm (e.g. the ppm) then 1428 * we just do a retry with all available paths. 1429 * If we already use the full opm, something is amiss, and we 1430 * need a full path verification. 1431 */ 1432 if (test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) { 1433 DBF_DEV_EVENT(DBF_WARNING, device, 1434 "start_IO: selected paths gone (%x)", 1435 cqr->lpm); 1436 } else if (cqr->lpm != device->path_data.opm) { 1437 cqr->lpm = device->path_data.opm; 1438 DBF_DEV_EVENT(DBF_DEBUG, device, "%s", 1439 "start_IO: selected paths gone," 1440 " retry on all paths"); 1441 } else { 1442 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1443 "start_IO: all paths in opm gone," 1444 " do path verification"); 1445 dasd_generic_last_path_gone(device); 1446 device->path_data.opm = 0; 1447 device->path_data.ppm = 0; 1448 device->path_data.npm = 0; 1449 device->path_data.tbvpm = 1450 ccw_device_get_path_mask(device->cdev); 1451 } 1452 break; 1453 case -ENODEV: 1454 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1455 "start_IO: -ENODEV device gone, retry"); 1456 break; 1457 case -EIO: 1458 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1459 "start_IO: -EIO device gone, retry"); 1460 break; 1461 case -EINVAL: 1462 /* most likely caused in power management context */ 1463 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1464 "start_IO: -EINVAL device currently " 1465 "not accessible"); 1466 break; 1467 default: 1468 /* internal error 11 - unknown rc */ 1469 snprintf(errorstring, ERRORLENGTH, "11 %d", rc); 1470 dev_err(&device->cdev->dev, 1471 "An error occurred in the DASD device driver, " 1472 "reason=%s\n", errorstring); 1473 BUG(); 1474 break; 1475 } 1476 cqr->intrc = rc; 1477 return rc; 1478 } 1479 EXPORT_SYMBOL(dasd_start_IO); 1480 1481 /* 1482 * Timeout function for dasd devices. This is used for different purposes 1483 * 1) missing interrupt handler for normal operation 1484 * 2) delayed start of request where start_IO failed with -EBUSY 1485 * 3) timeout for missing state change interrupts 1486 * The head of the ccw queue will have status DASD_CQR_IN_IO for 1), 1487 * DASD_CQR_QUEUED for 2) and 3). 1488 */ 1489 static void dasd_device_timeout(unsigned long ptr) 1490 { 1491 unsigned long flags; 1492 struct dasd_device *device; 1493 1494 device = (struct dasd_device *) ptr; 1495 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 1496 /* re-activate request queue */ 1497 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING); 1498 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 1499 dasd_schedule_device_bh(device); 1500 } 1501 1502 /* 1503 * Setup timeout for a device in jiffies. 1504 */ 1505 void dasd_device_set_timer(struct dasd_device *device, int expires) 1506 { 1507 if (expires == 0) 1508 del_timer(&device->timer); 1509 else 1510 mod_timer(&device->timer, jiffies + expires); 1511 } 1512 EXPORT_SYMBOL(dasd_device_set_timer); 1513 1514 /* 1515 * Clear timeout for a device. 1516 */ 1517 void dasd_device_clear_timer(struct dasd_device *device) 1518 { 1519 del_timer(&device->timer); 1520 } 1521 EXPORT_SYMBOL(dasd_device_clear_timer); 1522 1523 static void dasd_handle_killed_request(struct ccw_device *cdev, 1524 unsigned long intparm) 1525 { 1526 struct dasd_ccw_req *cqr; 1527 struct dasd_device *device; 1528 1529 if (!intparm) 1530 return; 1531 cqr = (struct dasd_ccw_req *) intparm; 1532 if (cqr->status != DASD_CQR_IN_IO) { 1533 DBF_EVENT_DEVID(DBF_DEBUG, cdev, 1534 "invalid status in handle_killed_request: " 1535 "%02x", cqr->status); 1536 return; 1537 } 1538 1539 device = dasd_device_from_cdev_locked(cdev); 1540 if (IS_ERR(device)) { 1541 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s", 1542 "unable to get device from cdev"); 1543 return; 1544 } 1545 1546 if (!cqr->startdev || 1547 device != cqr->startdev || 1548 strncmp(cqr->startdev->discipline->ebcname, 1549 (char *) &cqr->magic, 4)) { 1550 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s", 1551 "invalid device in request"); 1552 dasd_put_device(device); 1553 return; 1554 } 1555 1556 /* Schedule request to be retried. */ 1557 cqr->status = DASD_CQR_QUEUED; 1558 1559 dasd_device_clear_timer(device); 1560 dasd_schedule_device_bh(device); 1561 dasd_put_device(device); 1562 } 1563 1564 void dasd_generic_handle_state_change(struct dasd_device *device) 1565 { 1566 /* First of all start sense subsystem status request. */ 1567 dasd_eer_snss(device); 1568 1569 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING); 1570 dasd_schedule_device_bh(device); 1571 if (device->block) 1572 dasd_schedule_block_bh(device->block); 1573 } 1574 EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change); 1575 1576 /* 1577 * Interrupt handler for "normal" ssch-io based dasd devices. 1578 */ 1579 void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm, 1580 struct irb *irb) 1581 { 1582 struct dasd_ccw_req *cqr, *next; 1583 struct dasd_device *device; 1584 unsigned long long now; 1585 int expires; 1586 1587 if (IS_ERR(irb)) { 1588 switch (PTR_ERR(irb)) { 1589 case -EIO: 1590 break; 1591 case -ETIMEDOUT: 1592 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: " 1593 "request timed out\n", __func__); 1594 break; 1595 default: 1596 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: " 1597 "unknown error %ld\n", __func__, 1598 PTR_ERR(irb)); 1599 } 1600 dasd_handle_killed_request(cdev, intparm); 1601 return; 1602 } 1603 1604 now = get_tod_clock(); 1605 cqr = (struct dasd_ccw_req *) intparm; 1606 /* check for conditions that should be handled immediately */ 1607 if (!cqr || 1608 !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) && 1609 scsw_cstat(&irb->scsw) == 0)) { 1610 if (cqr) 1611 memcpy(&cqr->irb, irb, sizeof(*irb)); 1612 device = dasd_device_from_cdev_locked(cdev); 1613 if (IS_ERR(device)) 1614 return; 1615 /* ignore unsolicited interrupts for DIAG discipline */ 1616 if (device->discipline == dasd_diag_discipline_pointer) { 1617 dasd_put_device(device); 1618 return; 1619 } 1620 device->discipline->dump_sense_dbf(device, irb, "int"); 1621 if (device->features & DASD_FEATURE_ERPLOG) 1622 device->discipline->dump_sense(device, cqr, irb); 1623 device->discipline->check_for_device_change(device, cqr, irb); 1624 dasd_put_device(device); 1625 } 1626 1627 /* check for for attention message */ 1628 if (scsw_dstat(&irb->scsw) & DEV_STAT_ATTENTION) { 1629 device = dasd_device_from_cdev_locked(cdev); 1630 device->discipline->check_attention(device, irb->esw.esw1.lpum); 1631 dasd_put_device(device); 1632 } 1633 1634 if (!cqr) 1635 return; 1636 1637 device = (struct dasd_device *) cqr->startdev; 1638 if (!device || 1639 strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) { 1640 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s", 1641 "invalid device in request"); 1642 return; 1643 } 1644 1645 /* Check for clear pending */ 1646 if (cqr->status == DASD_CQR_CLEAR_PENDING && 1647 scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) { 1648 cqr->status = DASD_CQR_CLEARED; 1649 dasd_device_clear_timer(device); 1650 wake_up(&dasd_flush_wq); 1651 dasd_schedule_device_bh(device); 1652 return; 1653 } 1654 1655 /* check status - the request might have been killed by dyn detach */ 1656 if (cqr->status != DASD_CQR_IN_IO) { 1657 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, " 1658 "status %02x", dev_name(&cdev->dev), cqr->status); 1659 return; 1660 } 1661 1662 next = NULL; 1663 expires = 0; 1664 if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) && 1665 scsw_cstat(&irb->scsw) == 0) { 1666 /* request was completed successfully */ 1667 cqr->status = DASD_CQR_SUCCESS; 1668 cqr->stopclk = now; 1669 /* Start first request on queue if possible -> fast_io. */ 1670 if (cqr->devlist.next != &device->ccw_queue) { 1671 next = list_entry(cqr->devlist.next, 1672 struct dasd_ccw_req, devlist); 1673 } 1674 } else { /* error */ 1675 /* 1676 * If we don't want complex ERP for this request, then just 1677 * reset this and retry it in the fastpath 1678 */ 1679 if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) && 1680 cqr->retries > 0) { 1681 if (cqr->lpm == device->path_data.opm) 1682 DBF_DEV_EVENT(DBF_DEBUG, device, 1683 "default ERP in fastpath " 1684 "(%i retries left)", 1685 cqr->retries); 1686 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) 1687 cqr->lpm = device->path_data.opm; 1688 cqr->status = DASD_CQR_QUEUED; 1689 next = cqr; 1690 } else 1691 cqr->status = DASD_CQR_ERROR; 1692 } 1693 if (next && (next->status == DASD_CQR_QUEUED) && 1694 (!device->stopped)) { 1695 if (device->discipline->start_IO(next) == 0) 1696 expires = next->expires; 1697 } 1698 if (expires != 0) 1699 dasd_device_set_timer(device, expires); 1700 else 1701 dasd_device_clear_timer(device); 1702 dasd_schedule_device_bh(device); 1703 } 1704 EXPORT_SYMBOL(dasd_int_handler); 1705 1706 enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb) 1707 { 1708 struct dasd_device *device; 1709 1710 device = dasd_device_from_cdev_locked(cdev); 1711 1712 if (IS_ERR(device)) 1713 goto out; 1714 if (test_bit(DASD_FLAG_OFFLINE, &device->flags) || 1715 device->state != device->target || 1716 !device->discipline->check_for_device_change){ 1717 dasd_put_device(device); 1718 goto out; 1719 } 1720 if (device->discipline->dump_sense_dbf) 1721 device->discipline->dump_sense_dbf(device, irb, "uc"); 1722 device->discipline->check_for_device_change(device, NULL, irb); 1723 dasd_put_device(device); 1724 out: 1725 return UC_TODO_RETRY; 1726 } 1727 EXPORT_SYMBOL_GPL(dasd_generic_uc_handler); 1728 1729 /* 1730 * If we have an error on a dasd_block layer request then we cancel 1731 * and return all further requests from the same dasd_block as well. 1732 */ 1733 static void __dasd_device_recovery(struct dasd_device *device, 1734 struct dasd_ccw_req *ref_cqr) 1735 { 1736 struct list_head *l, *n; 1737 struct dasd_ccw_req *cqr; 1738 1739 /* 1740 * only requeue request that came from the dasd_block layer 1741 */ 1742 if (!ref_cqr->block) 1743 return; 1744 1745 list_for_each_safe(l, n, &device->ccw_queue) { 1746 cqr = list_entry(l, struct dasd_ccw_req, devlist); 1747 if (cqr->status == DASD_CQR_QUEUED && 1748 ref_cqr->block == cqr->block) { 1749 cqr->status = DASD_CQR_CLEARED; 1750 } 1751 } 1752 }; 1753 1754 /* 1755 * Remove those ccw requests from the queue that need to be returned 1756 * to the upper layer. 1757 */ 1758 static void __dasd_device_process_ccw_queue(struct dasd_device *device, 1759 struct list_head *final_queue) 1760 { 1761 struct list_head *l, *n; 1762 struct dasd_ccw_req *cqr; 1763 1764 /* Process request with final status. */ 1765 list_for_each_safe(l, n, &device->ccw_queue) { 1766 cqr = list_entry(l, struct dasd_ccw_req, devlist); 1767 1768 /* Skip any non-final request. */ 1769 if (cqr->status == DASD_CQR_QUEUED || 1770 cqr->status == DASD_CQR_IN_IO || 1771 cqr->status == DASD_CQR_CLEAR_PENDING) 1772 continue; 1773 if (cqr->status == DASD_CQR_ERROR) { 1774 __dasd_device_recovery(device, cqr); 1775 } 1776 /* Rechain finished requests to final queue */ 1777 list_move_tail(&cqr->devlist, final_queue); 1778 } 1779 } 1780 1781 /* 1782 * the cqrs from the final queue are returned to the upper layer 1783 * by setting a dasd_block state and calling the callback function 1784 */ 1785 static void __dasd_device_process_final_queue(struct dasd_device *device, 1786 struct list_head *final_queue) 1787 { 1788 struct list_head *l, *n; 1789 struct dasd_ccw_req *cqr; 1790 struct dasd_block *block; 1791 void (*callback)(struct dasd_ccw_req *, void *data); 1792 void *callback_data; 1793 char errorstring[ERRORLENGTH]; 1794 1795 list_for_each_safe(l, n, final_queue) { 1796 cqr = list_entry(l, struct dasd_ccw_req, devlist); 1797 list_del_init(&cqr->devlist); 1798 block = cqr->block; 1799 callback = cqr->callback; 1800 callback_data = cqr->callback_data; 1801 if (block) 1802 spin_lock_bh(&block->queue_lock); 1803 switch (cqr->status) { 1804 case DASD_CQR_SUCCESS: 1805 cqr->status = DASD_CQR_DONE; 1806 break; 1807 case DASD_CQR_ERROR: 1808 cqr->status = DASD_CQR_NEED_ERP; 1809 break; 1810 case DASD_CQR_CLEARED: 1811 cqr->status = DASD_CQR_TERMINATED; 1812 break; 1813 default: 1814 /* internal error 12 - wrong cqr status*/ 1815 snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status); 1816 dev_err(&device->cdev->dev, 1817 "An error occurred in the DASD device driver, " 1818 "reason=%s\n", errorstring); 1819 BUG(); 1820 } 1821 if (cqr->callback != NULL) 1822 (callback)(cqr, callback_data); 1823 if (block) 1824 spin_unlock_bh(&block->queue_lock); 1825 } 1826 } 1827 1828 /* 1829 * Take a look at the first request on the ccw queue and check 1830 * if it reached its expire time. If so, terminate the IO. 1831 */ 1832 static void __dasd_device_check_expire(struct dasd_device *device) 1833 { 1834 struct dasd_ccw_req *cqr; 1835 1836 if (list_empty(&device->ccw_queue)) 1837 return; 1838 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist); 1839 if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) && 1840 (time_after_eq(jiffies, cqr->expires + cqr->starttime))) { 1841 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) { 1842 /* 1843 * IO in safe offline processing should not 1844 * run out of retries 1845 */ 1846 cqr->retries++; 1847 } 1848 if (device->discipline->term_IO(cqr) != 0) { 1849 /* Hmpf, try again in 5 sec */ 1850 dev_err(&device->cdev->dev, 1851 "cqr %p timed out (%lus) but cannot be " 1852 "ended, retrying in 5 s\n", 1853 cqr, (cqr->expires/HZ)); 1854 cqr->expires += 5*HZ; 1855 dasd_device_set_timer(device, 5*HZ); 1856 } else { 1857 dev_err(&device->cdev->dev, 1858 "cqr %p timed out (%lus), %i retries " 1859 "remaining\n", cqr, (cqr->expires/HZ), 1860 cqr->retries); 1861 } 1862 } 1863 } 1864 1865 /* 1866 * Take a look at the first request on the ccw queue and check 1867 * if it needs to be started. 1868 */ 1869 static void __dasd_device_start_head(struct dasd_device *device) 1870 { 1871 struct dasd_ccw_req *cqr; 1872 int rc; 1873 1874 if (list_empty(&device->ccw_queue)) 1875 return; 1876 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist); 1877 if (cqr->status != DASD_CQR_QUEUED) 1878 return; 1879 /* when device is stopped, return request to previous layer 1880 * exception: only the disconnect or unresumed bits are set and the 1881 * cqr is a path verification request 1882 */ 1883 if (device->stopped && 1884 !(!(device->stopped & ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM)) 1885 && test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))) { 1886 cqr->intrc = -EAGAIN; 1887 cqr->status = DASD_CQR_CLEARED; 1888 dasd_schedule_device_bh(device); 1889 return; 1890 } 1891 1892 rc = device->discipline->start_IO(cqr); 1893 if (rc == 0) 1894 dasd_device_set_timer(device, cqr->expires); 1895 else if (rc == -EACCES) { 1896 dasd_schedule_device_bh(device); 1897 } else 1898 /* Hmpf, try again in 1/2 sec */ 1899 dasd_device_set_timer(device, 50); 1900 } 1901 1902 static void __dasd_device_check_path_events(struct dasd_device *device) 1903 { 1904 int rc; 1905 1906 if (device->path_data.tbvpm) { 1907 if (device->stopped & ~(DASD_STOPPED_DC_WAIT | 1908 DASD_UNRESUMED_PM)) 1909 return; 1910 rc = device->discipline->verify_path( 1911 device, device->path_data.tbvpm); 1912 if (rc) 1913 dasd_device_set_timer(device, 50); 1914 else 1915 device->path_data.tbvpm = 0; 1916 } 1917 }; 1918 1919 /* 1920 * Go through all request on the dasd_device request queue, 1921 * terminate them on the cdev if necessary, and return them to the 1922 * submitting layer via callback. 1923 * Note: 1924 * Make sure that all 'submitting layers' still exist when 1925 * this function is called!. In other words, when 'device' is a base 1926 * device then all block layer requests must have been removed before 1927 * via dasd_flush_block_queue. 1928 */ 1929 int dasd_flush_device_queue(struct dasd_device *device) 1930 { 1931 struct dasd_ccw_req *cqr, *n; 1932 int rc; 1933 struct list_head flush_queue; 1934 1935 INIT_LIST_HEAD(&flush_queue); 1936 spin_lock_irq(get_ccwdev_lock(device->cdev)); 1937 rc = 0; 1938 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) { 1939 /* Check status and move request to flush_queue */ 1940 switch (cqr->status) { 1941 case DASD_CQR_IN_IO: 1942 rc = device->discipline->term_IO(cqr); 1943 if (rc) { 1944 /* unable to terminate requeust */ 1945 dev_err(&device->cdev->dev, 1946 "Flushing the DASD request queue " 1947 "failed for request %p\n", cqr); 1948 /* stop flush processing */ 1949 goto finished; 1950 } 1951 break; 1952 case DASD_CQR_QUEUED: 1953 cqr->stopclk = get_tod_clock(); 1954 cqr->status = DASD_CQR_CLEARED; 1955 break; 1956 default: /* no need to modify the others */ 1957 break; 1958 } 1959 list_move_tail(&cqr->devlist, &flush_queue); 1960 } 1961 finished: 1962 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 1963 /* 1964 * After this point all requests must be in state CLEAR_PENDING, 1965 * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become 1966 * one of the others. 1967 */ 1968 list_for_each_entry_safe(cqr, n, &flush_queue, devlist) 1969 wait_event(dasd_flush_wq, 1970 (cqr->status != DASD_CQR_CLEAR_PENDING)); 1971 /* 1972 * Now set each request back to TERMINATED, DONE or NEED_ERP 1973 * and call the callback function of flushed requests 1974 */ 1975 __dasd_device_process_final_queue(device, &flush_queue); 1976 return rc; 1977 } 1978 EXPORT_SYMBOL_GPL(dasd_flush_device_queue); 1979 1980 /* 1981 * Acquire the device lock and process queues for the device. 1982 */ 1983 static void dasd_device_tasklet(struct dasd_device *device) 1984 { 1985 struct list_head final_queue; 1986 1987 atomic_set (&device->tasklet_scheduled, 0); 1988 INIT_LIST_HEAD(&final_queue); 1989 spin_lock_irq(get_ccwdev_lock(device->cdev)); 1990 /* Check expire time of first request on the ccw queue. */ 1991 __dasd_device_check_expire(device); 1992 /* find final requests on ccw queue */ 1993 __dasd_device_process_ccw_queue(device, &final_queue); 1994 __dasd_device_check_path_events(device); 1995 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 1996 /* Now call the callback function of requests with final status */ 1997 __dasd_device_process_final_queue(device, &final_queue); 1998 spin_lock_irq(get_ccwdev_lock(device->cdev)); 1999 /* Now check if the head of the ccw queue needs to be started. */ 2000 __dasd_device_start_head(device); 2001 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 2002 if (waitqueue_active(&shutdown_waitq)) 2003 wake_up(&shutdown_waitq); 2004 dasd_put_device(device); 2005 } 2006 2007 /* 2008 * Schedules a call to dasd_tasklet over the device tasklet. 2009 */ 2010 void dasd_schedule_device_bh(struct dasd_device *device) 2011 { 2012 /* Protect against rescheduling. */ 2013 if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0) 2014 return; 2015 dasd_get_device(device); 2016 tasklet_hi_schedule(&device->tasklet); 2017 } 2018 EXPORT_SYMBOL(dasd_schedule_device_bh); 2019 2020 void dasd_device_set_stop_bits(struct dasd_device *device, int bits) 2021 { 2022 device->stopped |= bits; 2023 } 2024 EXPORT_SYMBOL_GPL(dasd_device_set_stop_bits); 2025 2026 void dasd_device_remove_stop_bits(struct dasd_device *device, int bits) 2027 { 2028 device->stopped &= ~bits; 2029 if (!device->stopped) 2030 wake_up(&generic_waitq); 2031 } 2032 EXPORT_SYMBOL_GPL(dasd_device_remove_stop_bits); 2033 2034 /* 2035 * Queue a request to the head of the device ccw_queue. 2036 * Start the I/O if possible. 2037 */ 2038 void dasd_add_request_head(struct dasd_ccw_req *cqr) 2039 { 2040 struct dasd_device *device; 2041 unsigned long flags; 2042 2043 device = cqr->startdev; 2044 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 2045 cqr->status = DASD_CQR_QUEUED; 2046 list_add(&cqr->devlist, &device->ccw_queue); 2047 /* let the bh start the request to keep them in order */ 2048 dasd_schedule_device_bh(device); 2049 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 2050 } 2051 EXPORT_SYMBOL(dasd_add_request_head); 2052 2053 /* 2054 * Queue a request to the tail of the device ccw_queue. 2055 * Start the I/O if possible. 2056 */ 2057 void dasd_add_request_tail(struct dasd_ccw_req *cqr) 2058 { 2059 struct dasd_device *device; 2060 unsigned long flags; 2061 2062 device = cqr->startdev; 2063 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 2064 cqr->status = DASD_CQR_QUEUED; 2065 list_add_tail(&cqr->devlist, &device->ccw_queue); 2066 /* let the bh start the request to keep them in order */ 2067 dasd_schedule_device_bh(device); 2068 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 2069 } 2070 EXPORT_SYMBOL(dasd_add_request_tail); 2071 2072 /* 2073 * Wakeup helper for the 'sleep_on' functions. 2074 */ 2075 void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data) 2076 { 2077 spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev)); 2078 cqr->callback_data = DASD_SLEEPON_END_TAG; 2079 spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev)); 2080 wake_up(&generic_waitq); 2081 } 2082 EXPORT_SYMBOL_GPL(dasd_wakeup_cb); 2083 2084 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr) 2085 { 2086 struct dasd_device *device; 2087 int rc; 2088 2089 device = cqr->startdev; 2090 spin_lock_irq(get_ccwdev_lock(device->cdev)); 2091 rc = (cqr->callback_data == DASD_SLEEPON_END_TAG); 2092 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 2093 return rc; 2094 } 2095 2096 /* 2097 * checks if error recovery is necessary, returns 1 if yes, 0 otherwise. 2098 */ 2099 static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr) 2100 { 2101 struct dasd_device *device; 2102 dasd_erp_fn_t erp_fn; 2103 2104 if (cqr->status == DASD_CQR_FILLED) 2105 return 0; 2106 device = cqr->startdev; 2107 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) { 2108 if (cqr->status == DASD_CQR_TERMINATED) { 2109 device->discipline->handle_terminated_request(cqr); 2110 return 1; 2111 } 2112 if (cqr->status == DASD_CQR_NEED_ERP) { 2113 erp_fn = device->discipline->erp_action(cqr); 2114 erp_fn(cqr); 2115 return 1; 2116 } 2117 if (cqr->status == DASD_CQR_FAILED) 2118 dasd_log_sense(cqr, &cqr->irb); 2119 if (cqr->refers) { 2120 __dasd_process_erp(device, cqr); 2121 return 1; 2122 } 2123 } 2124 return 0; 2125 } 2126 2127 static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr) 2128 { 2129 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) { 2130 if (cqr->refers) /* erp is not done yet */ 2131 return 1; 2132 return ((cqr->status != DASD_CQR_DONE) && 2133 (cqr->status != DASD_CQR_FAILED)); 2134 } else 2135 return (cqr->status == DASD_CQR_FILLED); 2136 } 2137 2138 static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible) 2139 { 2140 struct dasd_device *device; 2141 int rc; 2142 struct list_head ccw_queue; 2143 struct dasd_ccw_req *cqr; 2144 2145 INIT_LIST_HEAD(&ccw_queue); 2146 maincqr->status = DASD_CQR_FILLED; 2147 device = maincqr->startdev; 2148 list_add(&maincqr->blocklist, &ccw_queue); 2149 for (cqr = maincqr; __dasd_sleep_on_loop_condition(cqr); 2150 cqr = list_first_entry(&ccw_queue, 2151 struct dasd_ccw_req, blocklist)) { 2152 2153 if (__dasd_sleep_on_erp(cqr)) 2154 continue; 2155 if (cqr->status != DASD_CQR_FILLED) /* could be failed */ 2156 continue; 2157 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) && 2158 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { 2159 cqr->status = DASD_CQR_FAILED; 2160 cqr->intrc = -EPERM; 2161 continue; 2162 } 2163 /* Non-temporary stop condition will trigger fail fast */ 2164 if (device->stopped & ~DASD_STOPPED_PENDING && 2165 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) && 2166 (!dasd_eer_enabled(device))) { 2167 cqr->status = DASD_CQR_FAILED; 2168 cqr->intrc = -ENOLINK; 2169 continue; 2170 } 2171 /* 2172 * Don't try to start requests if device is stopped 2173 * except path verification requests 2174 */ 2175 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) { 2176 if (interruptible) { 2177 rc = wait_event_interruptible( 2178 generic_waitq, !(device->stopped)); 2179 if (rc == -ERESTARTSYS) { 2180 cqr->status = DASD_CQR_FAILED; 2181 maincqr->intrc = rc; 2182 continue; 2183 } 2184 } else 2185 wait_event(generic_waitq, !(device->stopped)); 2186 } 2187 if (!cqr->callback) 2188 cqr->callback = dasd_wakeup_cb; 2189 2190 cqr->callback_data = DASD_SLEEPON_START_TAG; 2191 dasd_add_request_tail(cqr); 2192 if (interruptible) { 2193 rc = wait_event_interruptible( 2194 generic_waitq, _wait_for_wakeup(cqr)); 2195 if (rc == -ERESTARTSYS) { 2196 dasd_cancel_req(cqr); 2197 /* wait (non-interruptible) for final status */ 2198 wait_event(generic_waitq, 2199 _wait_for_wakeup(cqr)); 2200 cqr->status = DASD_CQR_FAILED; 2201 maincqr->intrc = rc; 2202 continue; 2203 } 2204 } else 2205 wait_event(generic_waitq, _wait_for_wakeup(cqr)); 2206 } 2207 2208 maincqr->endclk = get_tod_clock(); 2209 if ((maincqr->status != DASD_CQR_DONE) && 2210 (maincqr->intrc != -ERESTARTSYS)) 2211 dasd_log_sense(maincqr, &maincqr->irb); 2212 if (maincqr->status == DASD_CQR_DONE) 2213 rc = 0; 2214 else if (maincqr->intrc) 2215 rc = maincqr->intrc; 2216 else 2217 rc = -EIO; 2218 return rc; 2219 } 2220 2221 static inline int _wait_for_wakeup_queue(struct list_head *ccw_queue) 2222 { 2223 struct dasd_ccw_req *cqr; 2224 2225 list_for_each_entry(cqr, ccw_queue, blocklist) { 2226 if (cqr->callback_data != DASD_SLEEPON_END_TAG) 2227 return 0; 2228 } 2229 2230 return 1; 2231 } 2232 2233 static int _dasd_sleep_on_queue(struct list_head *ccw_queue, int interruptible) 2234 { 2235 struct dasd_device *device; 2236 struct dasd_ccw_req *cqr, *n; 2237 int rc; 2238 2239 retry: 2240 list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) { 2241 device = cqr->startdev; 2242 if (cqr->status != DASD_CQR_FILLED) /*could be failed*/ 2243 continue; 2244 2245 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) && 2246 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { 2247 cqr->status = DASD_CQR_FAILED; 2248 cqr->intrc = -EPERM; 2249 continue; 2250 } 2251 /*Non-temporary stop condition will trigger fail fast*/ 2252 if (device->stopped & ~DASD_STOPPED_PENDING && 2253 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) && 2254 !dasd_eer_enabled(device)) { 2255 cqr->status = DASD_CQR_FAILED; 2256 cqr->intrc = -EAGAIN; 2257 continue; 2258 } 2259 2260 /*Don't try to start requests if device is stopped*/ 2261 if (interruptible) { 2262 rc = wait_event_interruptible( 2263 generic_waitq, !device->stopped); 2264 if (rc == -ERESTARTSYS) { 2265 cqr->status = DASD_CQR_FAILED; 2266 cqr->intrc = rc; 2267 continue; 2268 } 2269 } else 2270 wait_event(generic_waitq, !(device->stopped)); 2271 2272 if (!cqr->callback) 2273 cqr->callback = dasd_wakeup_cb; 2274 cqr->callback_data = DASD_SLEEPON_START_TAG; 2275 dasd_add_request_tail(cqr); 2276 } 2277 2278 wait_event(generic_waitq, _wait_for_wakeup_queue(ccw_queue)); 2279 2280 rc = 0; 2281 list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) { 2282 /* 2283 * for alias devices simplify error recovery and 2284 * return to upper layer 2285 * do not skip ERP requests 2286 */ 2287 if (cqr->startdev != cqr->basedev && !cqr->refers && 2288 (cqr->status == DASD_CQR_TERMINATED || 2289 cqr->status == DASD_CQR_NEED_ERP)) 2290 return -EAGAIN; 2291 2292 /* normal recovery for basedev IO */ 2293 if (__dasd_sleep_on_erp(cqr)) 2294 /* handle erp first */ 2295 goto retry; 2296 } 2297 2298 return 0; 2299 } 2300 2301 /* 2302 * Queue a request to the tail of the device ccw_queue and wait for 2303 * it's completion. 2304 */ 2305 int dasd_sleep_on(struct dasd_ccw_req *cqr) 2306 { 2307 return _dasd_sleep_on(cqr, 0); 2308 } 2309 EXPORT_SYMBOL(dasd_sleep_on); 2310 2311 /* 2312 * Start requests from a ccw_queue and wait for their completion. 2313 */ 2314 int dasd_sleep_on_queue(struct list_head *ccw_queue) 2315 { 2316 return _dasd_sleep_on_queue(ccw_queue, 0); 2317 } 2318 EXPORT_SYMBOL(dasd_sleep_on_queue); 2319 2320 /* 2321 * Queue a request to the tail of the device ccw_queue and wait 2322 * interruptible for it's completion. 2323 */ 2324 int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr) 2325 { 2326 return _dasd_sleep_on(cqr, 1); 2327 } 2328 EXPORT_SYMBOL(dasd_sleep_on_interruptible); 2329 2330 /* 2331 * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock 2332 * for eckd devices) the currently running request has to be terminated 2333 * and be put back to status queued, before the special request is added 2334 * to the head of the queue. Then the special request is waited on normally. 2335 */ 2336 static inline int _dasd_term_running_cqr(struct dasd_device *device) 2337 { 2338 struct dasd_ccw_req *cqr; 2339 int rc; 2340 2341 if (list_empty(&device->ccw_queue)) 2342 return 0; 2343 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist); 2344 rc = device->discipline->term_IO(cqr); 2345 if (!rc) 2346 /* 2347 * CQR terminated because a more important request is pending. 2348 * Undo decreasing of retry counter because this is 2349 * not an error case. 2350 */ 2351 cqr->retries++; 2352 return rc; 2353 } 2354 2355 int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr) 2356 { 2357 struct dasd_device *device; 2358 int rc; 2359 2360 device = cqr->startdev; 2361 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) && 2362 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { 2363 cqr->status = DASD_CQR_FAILED; 2364 cqr->intrc = -EPERM; 2365 return -EIO; 2366 } 2367 spin_lock_irq(get_ccwdev_lock(device->cdev)); 2368 rc = _dasd_term_running_cqr(device); 2369 if (rc) { 2370 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 2371 return rc; 2372 } 2373 cqr->callback = dasd_wakeup_cb; 2374 cqr->callback_data = DASD_SLEEPON_START_TAG; 2375 cqr->status = DASD_CQR_QUEUED; 2376 /* 2377 * add new request as second 2378 * first the terminated cqr needs to be finished 2379 */ 2380 list_add(&cqr->devlist, device->ccw_queue.next); 2381 2382 /* let the bh start the request to keep them in order */ 2383 dasd_schedule_device_bh(device); 2384 2385 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 2386 2387 wait_event(generic_waitq, _wait_for_wakeup(cqr)); 2388 2389 if (cqr->status == DASD_CQR_DONE) 2390 rc = 0; 2391 else if (cqr->intrc) 2392 rc = cqr->intrc; 2393 else 2394 rc = -EIO; 2395 2396 /* kick tasklets */ 2397 dasd_schedule_device_bh(device); 2398 if (device->block) 2399 dasd_schedule_block_bh(device->block); 2400 2401 return rc; 2402 } 2403 EXPORT_SYMBOL(dasd_sleep_on_immediatly); 2404 2405 /* 2406 * Cancels a request that was started with dasd_sleep_on_req. 2407 * This is useful to timeout requests. The request will be 2408 * terminated if it is currently in i/o. 2409 * Returns 0 if request termination was successful 2410 * negative error code if termination failed 2411 * Cancellation of a request is an asynchronous operation! The calling 2412 * function has to wait until the request is properly returned via callback. 2413 */ 2414 int dasd_cancel_req(struct dasd_ccw_req *cqr) 2415 { 2416 struct dasd_device *device = cqr->startdev; 2417 unsigned long flags; 2418 int rc; 2419 2420 rc = 0; 2421 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 2422 switch (cqr->status) { 2423 case DASD_CQR_QUEUED: 2424 /* request was not started - just set to cleared */ 2425 cqr->status = DASD_CQR_CLEARED; 2426 if (cqr->callback_data == DASD_SLEEPON_START_TAG) 2427 cqr->callback_data = DASD_SLEEPON_END_TAG; 2428 break; 2429 case DASD_CQR_IN_IO: 2430 /* request in IO - terminate IO and release again */ 2431 rc = device->discipline->term_IO(cqr); 2432 if (rc) { 2433 dev_err(&device->cdev->dev, 2434 "Cancelling request %p failed with rc=%d\n", 2435 cqr, rc); 2436 } else { 2437 cqr->stopclk = get_tod_clock(); 2438 } 2439 break; 2440 default: /* already finished or clear pending - do nothing */ 2441 break; 2442 } 2443 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 2444 dasd_schedule_device_bh(device); 2445 return rc; 2446 } 2447 EXPORT_SYMBOL(dasd_cancel_req); 2448 2449 /* 2450 * SECTION: Operations of the dasd_block layer. 2451 */ 2452 2453 /* 2454 * Timeout function for dasd_block. This is used when the block layer 2455 * is waiting for something that may not come reliably, (e.g. a state 2456 * change interrupt) 2457 */ 2458 static void dasd_block_timeout(unsigned long ptr) 2459 { 2460 unsigned long flags; 2461 struct dasd_block *block; 2462 2463 block = (struct dasd_block *) ptr; 2464 spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags); 2465 /* re-activate request queue */ 2466 dasd_device_remove_stop_bits(block->base, DASD_STOPPED_PENDING); 2467 spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags); 2468 dasd_schedule_block_bh(block); 2469 } 2470 2471 /* 2472 * Setup timeout for a dasd_block in jiffies. 2473 */ 2474 void dasd_block_set_timer(struct dasd_block *block, int expires) 2475 { 2476 if (expires == 0) 2477 del_timer(&block->timer); 2478 else 2479 mod_timer(&block->timer, jiffies + expires); 2480 } 2481 EXPORT_SYMBOL(dasd_block_set_timer); 2482 2483 /* 2484 * Clear timeout for a dasd_block. 2485 */ 2486 void dasd_block_clear_timer(struct dasd_block *block) 2487 { 2488 del_timer(&block->timer); 2489 } 2490 EXPORT_SYMBOL(dasd_block_clear_timer); 2491 2492 /* 2493 * Process finished error recovery ccw. 2494 */ 2495 static void __dasd_process_erp(struct dasd_device *device, 2496 struct dasd_ccw_req *cqr) 2497 { 2498 dasd_erp_fn_t erp_fn; 2499 2500 if (cqr->status == DASD_CQR_DONE) 2501 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful"); 2502 else 2503 dev_err(&device->cdev->dev, "ERP failed for the DASD\n"); 2504 erp_fn = device->discipline->erp_postaction(cqr); 2505 erp_fn(cqr); 2506 } 2507 2508 /* 2509 * Fetch requests from the block device queue. 2510 */ 2511 static void __dasd_process_request_queue(struct dasd_block *block) 2512 { 2513 struct request_queue *queue; 2514 struct request *req; 2515 struct dasd_ccw_req *cqr; 2516 struct dasd_device *basedev; 2517 unsigned long flags; 2518 queue = block->request_queue; 2519 basedev = block->base; 2520 /* No queue ? Then there is nothing to do. */ 2521 if (queue == NULL) 2522 return; 2523 2524 /* 2525 * We requeue request from the block device queue to the ccw 2526 * queue only in two states. In state DASD_STATE_READY the 2527 * partition detection is done and we need to requeue requests 2528 * for that. State DASD_STATE_ONLINE is normal block device 2529 * operation. 2530 */ 2531 if (basedev->state < DASD_STATE_READY) { 2532 while ((req = blk_fetch_request(block->request_queue))) 2533 __blk_end_request_all(req, -EIO); 2534 return; 2535 } 2536 2537 /* if device ist stopped do not fetch new requests */ 2538 if (basedev->stopped) 2539 return; 2540 2541 /* Now we try to fetch requests from the request queue */ 2542 while ((req = blk_peek_request(queue))) { 2543 if (basedev->features & DASD_FEATURE_READONLY && 2544 rq_data_dir(req) == WRITE) { 2545 DBF_DEV_EVENT(DBF_ERR, basedev, 2546 "Rejecting write request %p", 2547 req); 2548 blk_start_request(req); 2549 __blk_end_request_all(req, -EIO); 2550 continue; 2551 } 2552 if (test_bit(DASD_FLAG_ABORTALL, &basedev->flags) && 2553 (basedev->features & DASD_FEATURE_FAILFAST || 2554 blk_noretry_request(req))) { 2555 DBF_DEV_EVENT(DBF_ERR, basedev, 2556 "Rejecting failfast request %p", 2557 req); 2558 blk_start_request(req); 2559 __blk_end_request_all(req, -ETIMEDOUT); 2560 continue; 2561 } 2562 cqr = basedev->discipline->build_cp(basedev, block, req); 2563 if (IS_ERR(cqr)) { 2564 if (PTR_ERR(cqr) == -EBUSY) 2565 break; /* normal end condition */ 2566 if (PTR_ERR(cqr) == -ENOMEM) 2567 break; /* terminate request queue loop */ 2568 if (PTR_ERR(cqr) == -EAGAIN) { 2569 /* 2570 * The current request cannot be build right 2571 * now, we have to try later. If this request 2572 * is the head-of-queue we stop the device 2573 * for 1/2 second. 2574 */ 2575 if (!list_empty(&block->ccw_queue)) 2576 break; 2577 spin_lock_irqsave( 2578 get_ccwdev_lock(basedev->cdev), flags); 2579 dasd_device_set_stop_bits(basedev, 2580 DASD_STOPPED_PENDING); 2581 spin_unlock_irqrestore( 2582 get_ccwdev_lock(basedev->cdev), flags); 2583 dasd_block_set_timer(block, HZ/2); 2584 break; 2585 } 2586 DBF_DEV_EVENT(DBF_ERR, basedev, 2587 "CCW creation failed (rc=%ld) " 2588 "on request %p", 2589 PTR_ERR(cqr), req); 2590 blk_start_request(req); 2591 __blk_end_request_all(req, -EIO); 2592 continue; 2593 } 2594 /* 2595 * Note: callback is set to dasd_return_cqr_cb in 2596 * __dasd_block_start_head to cover erp requests as well 2597 */ 2598 cqr->callback_data = (void *) req; 2599 cqr->status = DASD_CQR_FILLED; 2600 req->completion_data = cqr; 2601 blk_start_request(req); 2602 list_add_tail(&cqr->blocklist, &block->ccw_queue); 2603 INIT_LIST_HEAD(&cqr->devlist); 2604 dasd_profile_start(block, cqr, req); 2605 } 2606 } 2607 2608 static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr) 2609 { 2610 struct request *req; 2611 int status; 2612 int error = 0; 2613 2614 req = (struct request *) cqr->callback_data; 2615 dasd_profile_end(cqr->block, cqr, req); 2616 status = cqr->block->base->discipline->free_cp(cqr, req); 2617 if (status < 0) 2618 error = status; 2619 else if (status == 0) { 2620 if (cqr->intrc == -EPERM) 2621 error = -EBADE; 2622 else if (cqr->intrc == -ENOLINK || 2623 cqr->intrc == -ETIMEDOUT) 2624 error = cqr->intrc; 2625 else 2626 error = -EIO; 2627 } 2628 __blk_end_request_all(req, error); 2629 } 2630 2631 /* 2632 * Process ccw request queue. 2633 */ 2634 static void __dasd_process_block_ccw_queue(struct dasd_block *block, 2635 struct list_head *final_queue) 2636 { 2637 struct list_head *l, *n; 2638 struct dasd_ccw_req *cqr; 2639 dasd_erp_fn_t erp_fn; 2640 unsigned long flags; 2641 struct dasd_device *base = block->base; 2642 2643 restart: 2644 /* Process request with final status. */ 2645 list_for_each_safe(l, n, &block->ccw_queue) { 2646 cqr = list_entry(l, struct dasd_ccw_req, blocklist); 2647 if (cqr->status != DASD_CQR_DONE && 2648 cqr->status != DASD_CQR_FAILED && 2649 cqr->status != DASD_CQR_NEED_ERP && 2650 cqr->status != DASD_CQR_TERMINATED) 2651 continue; 2652 2653 if (cqr->status == DASD_CQR_TERMINATED) { 2654 base->discipline->handle_terminated_request(cqr); 2655 goto restart; 2656 } 2657 2658 /* Process requests that may be recovered */ 2659 if (cqr->status == DASD_CQR_NEED_ERP) { 2660 erp_fn = base->discipline->erp_action(cqr); 2661 if (IS_ERR(erp_fn(cqr))) 2662 continue; 2663 goto restart; 2664 } 2665 2666 /* log sense for fatal error */ 2667 if (cqr->status == DASD_CQR_FAILED) { 2668 dasd_log_sense(cqr, &cqr->irb); 2669 } 2670 2671 /* First of all call extended error reporting. */ 2672 if (dasd_eer_enabled(base) && 2673 cqr->status == DASD_CQR_FAILED) { 2674 dasd_eer_write(base, cqr, DASD_EER_FATALERROR); 2675 2676 /* restart request */ 2677 cqr->status = DASD_CQR_FILLED; 2678 cqr->retries = 255; 2679 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags); 2680 dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE); 2681 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), 2682 flags); 2683 goto restart; 2684 } 2685 2686 /* Process finished ERP request. */ 2687 if (cqr->refers) { 2688 __dasd_process_erp(base, cqr); 2689 goto restart; 2690 } 2691 2692 /* Rechain finished requests to final queue */ 2693 cqr->endclk = get_tod_clock(); 2694 list_move_tail(&cqr->blocklist, final_queue); 2695 } 2696 } 2697 2698 static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data) 2699 { 2700 dasd_schedule_block_bh(cqr->block); 2701 } 2702 2703 static void __dasd_block_start_head(struct dasd_block *block) 2704 { 2705 struct dasd_ccw_req *cqr; 2706 2707 if (list_empty(&block->ccw_queue)) 2708 return; 2709 /* We allways begin with the first requests on the queue, as some 2710 * of previously started requests have to be enqueued on a 2711 * dasd_device again for error recovery. 2712 */ 2713 list_for_each_entry(cqr, &block->ccw_queue, blocklist) { 2714 if (cqr->status != DASD_CQR_FILLED) 2715 continue; 2716 if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) && 2717 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { 2718 cqr->status = DASD_CQR_FAILED; 2719 cqr->intrc = -EPERM; 2720 dasd_schedule_block_bh(block); 2721 continue; 2722 } 2723 /* Non-temporary stop condition will trigger fail fast */ 2724 if (block->base->stopped & ~DASD_STOPPED_PENDING && 2725 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) && 2726 (!dasd_eer_enabled(block->base))) { 2727 cqr->status = DASD_CQR_FAILED; 2728 cqr->intrc = -ENOLINK; 2729 dasd_schedule_block_bh(block); 2730 continue; 2731 } 2732 /* Don't try to start requests if device is stopped */ 2733 if (block->base->stopped) 2734 return; 2735 2736 /* just a fail safe check, should not happen */ 2737 if (!cqr->startdev) 2738 cqr->startdev = block->base; 2739 2740 /* make sure that the requests we submit find their way back */ 2741 cqr->callback = dasd_return_cqr_cb; 2742 2743 dasd_add_request_tail(cqr); 2744 } 2745 } 2746 2747 /* 2748 * Central dasd_block layer routine. Takes requests from the generic 2749 * block layer request queue, creates ccw requests, enqueues them on 2750 * a dasd_device and processes ccw requests that have been returned. 2751 */ 2752 static void dasd_block_tasklet(struct dasd_block *block) 2753 { 2754 struct list_head final_queue; 2755 struct list_head *l, *n; 2756 struct dasd_ccw_req *cqr; 2757 2758 atomic_set(&block->tasklet_scheduled, 0); 2759 INIT_LIST_HEAD(&final_queue); 2760 spin_lock(&block->queue_lock); 2761 /* Finish off requests on ccw queue */ 2762 __dasd_process_block_ccw_queue(block, &final_queue); 2763 spin_unlock(&block->queue_lock); 2764 /* Now call the callback function of requests with final status */ 2765 spin_lock_irq(&block->request_queue_lock); 2766 list_for_each_safe(l, n, &final_queue) { 2767 cqr = list_entry(l, struct dasd_ccw_req, blocklist); 2768 list_del_init(&cqr->blocklist); 2769 __dasd_cleanup_cqr(cqr); 2770 } 2771 spin_lock(&block->queue_lock); 2772 /* Get new request from the block device request queue */ 2773 __dasd_process_request_queue(block); 2774 /* Now check if the head of the ccw queue needs to be started. */ 2775 __dasd_block_start_head(block); 2776 spin_unlock(&block->queue_lock); 2777 spin_unlock_irq(&block->request_queue_lock); 2778 if (waitqueue_active(&shutdown_waitq)) 2779 wake_up(&shutdown_waitq); 2780 dasd_put_device(block->base); 2781 } 2782 2783 static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data) 2784 { 2785 wake_up(&dasd_flush_wq); 2786 } 2787 2788 /* 2789 * Requeue a request back to the block request queue 2790 * only works for block requests 2791 */ 2792 static int _dasd_requeue_request(struct dasd_ccw_req *cqr) 2793 { 2794 struct dasd_block *block = cqr->block; 2795 struct request *req; 2796 unsigned long flags; 2797 2798 if (!block) 2799 return -EINVAL; 2800 spin_lock_irqsave(&block->queue_lock, flags); 2801 req = (struct request *) cqr->callback_data; 2802 blk_requeue_request(block->request_queue, req); 2803 spin_unlock_irqrestore(&block->queue_lock, flags); 2804 2805 return 0; 2806 } 2807 2808 /* 2809 * Go through all request on the dasd_block request queue, cancel them 2810 * on the respective dasd_device, and return them to the generic 2811 * block layer. 2812 */ 2813 static int dasd_flush_block_queue(struct dasd_block *block) 2814 { 2815 struct dasd_ccw_req *cqr, *n; 2816 int rc, i; 2817 struct list_head flush_queue; 2818 2819 INIT_LIST_HEAD(&flush_queue); 2820 spin_lock_bh(&block->queue_lock); 2821 rc = 0; 2822 restart: 2823 list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) { 2824 /* if this request currently owned by a dasd_device cancel it */ 2825 if (cqr->status >= DASD_CQR_QUEUED) 2826 rc = dasd_cancel_req(cqr); 2827 if (rc < 0) 2828 break; 2829 /* Rechain request (including erp chain) so it won't be 2830 * touched by the dasd_block_tasklet anymore. 2831 * Replace the callback so we notice when the request 2832 * is returned from the dasd_device layer. 2833 */ 2834 cqr->callback = _dasd_wake_block_flush_cb; 2835 for (i = 0; cqr != NULL; cqr = cqr->refers, i++) 2836 list_move_tail(&cqr->blocklist, &flush_queue); 2837 if (i > 1) 2838 /* moved more than one request - need to restart */ 2839 goto restart; 2840 } 2841 spin_unlock_bh(&block->queue_lock); 2842 /* Now call the callback function of flushed requests */ 2843 restart_cb: 2844 list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) { 2845 wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED)); 2846 /* Process finished ERP request. */ 2847 if (cqr->refers) { 2848 spin_lock_bh(&block->queue_lock); 2849 __dasd_process_erp(block->base, cqr); 2850 spin_unlock_bh(&block->queue_lock); 2851 /* restart list_for_xx loop since dasd_process_erp 2852 * might remove multiple elements */ 2853 goto restart_cb; 2854 } 2855 /* call the callback function */ 2856 spin_lock_irq(&block->request_queue_lock); 2857 cqr->endclk = get_tod_clock(); 2858 list_del_init(&cqr->blocklist); 2859 __dasd_cleanup_cqr(cqr); 2860 spin_unlock_irq(&block->request_queue_lock); 2861 } 2862 return rc; 2863 } 2864 2865 /* 2866 * Schedules a call to dasd_tasklet over the device tasklet. 2867 */ 2868 void dasd_schedule_block_bh(struct dasd_block *block) 2869 { 2870 /* Protect against rescheduling. */ 2871 if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0) 2872 return; 2873 /* life cycle of block is bound to it's base device */ 2874 dasd_get_device(block->base); 2875 tasklet_hi_schedule(&block->tasklet); 2876 } 2877 EXPORT_SYMBOL(dasd_schedule_block_bh); 2878 2879 2880 /* 2881 * SECTION: external block device operations 2882 * (request queue handling, open, release, etc.) 2883 */ 2884 2885 /* 2886 * Dasd request queue function. Called from ll_rw_blk.c 2887 */ 2888 static void do_dasd_request(struct request_queue *queue) 2889 { 2890 struct dasd_block *block; 2891 2892 block = queue->queuedata; 2893 spin_lock(&block->queue_lock); 2894 /* Get new request from the block device request queue */ 2895 __dasd_process_request_queue(block); 2896 /* Now check if the head of the ccw queue needs to be started. */ 2897 __dasd_block_start_head(block); 2898 spin_unlock(&block->queue_lock); 2899 } 2900 2901 /* 2902 * Block timeout callback, called from the block layer 2903 * 2904 * request_queue lock is held on entry. 2905 * 2906 * Return values: 2907 * BLK_EH_RESET_TIMER if the request should be left running 2908 * BLK_EH_NOT_HANDLED if the request is handled or terminated 2909 * by the driver. 2910 */ 2911 enum blk_eh_timer_return dasd_times_out(struct request *req) 2912 { 2913 struct dasd_ccw_req *cqr = req->completion_data; 2914 struct dasd_block *block = req->q->queuedata; 2915 struct dasd_device *device; 2916 int rc = 0; 2917 2918 if (!cqr) 2919 return BLK_EH_NOT_HANDLED; 2920 2921 device = cqr->startdev ? cqr->startdev : block->base; 2922 if (!device->blk_timeout) 2923 return BLK_EH_RESET_TIMER; 2924 DBF_DEV_EVENT(DBF_WARNING, device, 2925 " dasd_times_out cqr %p status %x", 2926 cqr, cqr->status); 2927 2928 spin_lock(&block->queue_lock); 2929 spin_lock(get_ccwdev_lock(device->cdev)); 2930 cqr->retries = -1; 2931 cqr->intrc = -ETIMEDOUT; 2932 if (cqr->status >= DASD_CQR_QUEUED) { 2933 spin_unlock(get_ccwdev_lock(device->cdev)); 2934 rc = dasd_cancel_req(cqr); 2935 } else if (cqr->status == DASD_CQR_FILLED || 2936 cqr->status == DASD_CQR_NEED_ERP) { 2937 cqr->status = DASD_CQR_TERMINATED; 2938 spin_unlock(get_ccwdev_lock(device->cdev)); 2939 } else if (cqr->status == DASD_CQR_IN_ERP) { 2940 struct dasd_ccw_req *searchcqr, *nextcqr, *tmpcqr; 2941 2942 list_for_each_entry_safe(searchcqr, nextcqr, 2943 &block->ccw_queue, blocklist) { 2944 tmpcqr = searchcqr; 2945 while (tmpcqr->refers) 2946 tmpcqr = tmpcqr->refers; 2947 if (tmpcqr != cqr) 2948 continue; 2949 /* searchcqr is an ERP request for cqr */ 2950 searchcqr->retries = -1; 2951 searchcqr->intrc = -ETIMEDOUT; 2952 if (searchcqr->status >= DASD_CQR_QUEUED) { 2953 spin_unlock(get_ccwdev_lock(device->cdev)); 2954 rc = dasd_cancel_req(searchcqr); 2955 spin_lock(get_ccwdev_lock(device->cdev)); 2956 } else if ((searchcqr->status == DASD_CQR_FILLED) || 2957 (searchcqr->status == DASD_CQR_NEED_ERP)) { 2958 searchcqr->status = DASD_CQR_TERMINATED; 2959 rc = 0; 2960 } else if (searchcqr->status == DASD_CQR_IN_ERP) { 2961 /* 2962 * Shouldn't happen; most recent ERP 2963 * request is at the front of queue 2964 */ 2965 continue; 2966 } 2967 break; 2968 } 2969 spin_unlock(get_ccwdev_lock(device->cdev)); 2970 } 2971 dasd_schedule_block_bh(block); 2972 spin_unlock(&block->queue_lock); 2973 2974 return rc ? BLK_EH_RESET_TIMER : BLK_EH_NOT_HANDLED; 2975 } 2976 2977 /* 2978 * Allocate and initialize request queue and default I/O scheduler. 2979 */ 2980 static int dasd_alloc_queue(struct dasd_block *block) 2981 { 2982 block->request_queue = blk_init_queue(do_dasd_request, 2983 &block->request_queue_lock); 2984 if (block->request_queue == NULL) 2985 return -ENOMEM; 2986 2987 block->request_queue->queuedata = block; 2988 2989 return 0; 2990 } 2991 2992 /* 2993 * Allocate and initialize request queue. 2994 */ 2995 static void dasd_setup_queue(struct dasd_block *block) 2996 { 2997 int max; 2998 2999 if (block->base->features & DASD_FEATURE_USERAW) { 3000 /* 3001 * the max_blocks value for raw_track access is 256 3002 * it is higher than the native ECKD value because we 3003 * only need one ccw per track 3004 * so the max_hw_sectors are 3005 * 2048 x 512B = 1024kB = 16 tracks 3006 */ 3007 max = 2048; 3008 } else { 3009 max = block->base->discipline->max_blocks << block->s2b_shift; 3010 } 3011 blk_queue_logical_block_size(block->request_queue, 3012 block->bp_block); 3013 blk_queue_max_hw_sectors(block->request_queue, max); 3014 blk_queue_max_segments(block->request_queue, -1L); 3015 /* with page sized segments we can translate each segement into 3016 * one idaw/tidaw 3017 */ 3018 blk_queue_max_segment_size(block->request_queue, PAGE_SIZE); 3019 blk_queue_segment_boundary(block->request_queue, PAGE_SIZE - 1); 3020 } 3021 3022 /* 3023 * Deactivate and free request queue. 3024 */ 3025 static void dasd_free_queue(struct dasd_block *block) 3026 { 3027 if (block->request_queue) { 3028 blk_cleanup_queue(block->request_queue); 3029 block->request_queue = NULL; 3030 } 3031 } 3032 3033 /* 3034 * Flush request on the request queue. 3035 */ 3036 static void dasd_flush_request_queue(struct dasd_block *block) 3037 { 3038 struct request *req; 3039 3040 if (!block->request_queue) 3041 return; 3042 3043 spin_lock_irq(&block->request_queue_lock); 3044 while ((req = blk_fetch_request(block->request_queue))) 3045 __blk_end_request_all(req, -EIO); 3046 spin_unlock_irq(&block->request_queue_lock); 3047 } 3048 3049 static int dasd_open(struct block_device *bdev, fmode_t mode) 3050 { 3051 struct dasd_device *base; 3052 int rc; 3053 3054 base = dasd_device_from_gendisk(bdev->bd_disk); 3055 if (!base) 3056 return -ENODEV; 3057 3058 atomic_inc(&base->block->open_count); 3059 if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) { 3060 rc = -ENODEV; 3061 goto unlock; 3062 } 3063 3064 if (!try_module_get(base->discipline->owner)) { 3065 rc = -EINVAL; 3066 goto unlock; 3067 } 3068 3069 if (dasd_probeonly) { 3070 dev_info(&base->cdev->dev, 3071 "Accessing the DASD failed because it is in " 3072 "probeonly mode\n"); 3073 rc = -EPERM; 3074 goto out; 3075 } 3076 3077 if (base->state <= DASD_STATE_BASIC) { 3078 DBF_DEV_EVENT(DBF_ERR, base, " %s", 3079 " Cannot open unrecognized device"); 3080 rc = -ENODEV; 3081 goto out; 3082 } 3083 3084 if ((mode & FMODE_WRITE) && 3085 (test_bit(DASD_FLAG_DEVICE_RO, &base->flags) || 3086 (base->features & DASD_FEATURE_READONLY))) { 3087 rc = -EROFS; 3088 goto out; 3089 } 3090 3091 dasd_put_device(base); 3092 return 0; 3093 3094 out: 3095 module_put(base->discipline->owner); 3096 unlock: 3097 atomic_dec(&base->block->open_count); 3098 dasd_put_device(base); 3099 return rc; 3100 } 3101 3102 static void dasd_release(struct gendisk *disk, fmode_t mode) 3103 { 3104 struct dasd_device *base = dasd_device_from_gendisk(disk); 3105 if (base) { 3106 atomic_dec(&base->block->open_count); 3107 module_put(base->discipline->owner); 3108 dasd_put_device(base); 3109 } 3110 } 3111 3112 /* 3113 * Return disk geometry. 3114 */ 3115 static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 3116 { 3117 struct dasd_device *base; 3118 3119 base = dasd_device_from_gendisk(bdev->bd_disk); 3120 if (!base) 3121 return -ENODEV; 3122 3123 if (!base->discipline || 3124 !base->discipline->fill_geometry) { 3125 dasd_put_device(base); 3126 return -EINVAL; 3127 } 3128 base->discipline->fill_geometry(base->block, geo); 3129 geo->start = get_start_sect(bdev) >> base->block->s2b_shift; 3130 dasd_put_device(base); 3131 return 0; 3132 } 3133 3134 const struct block_device_operations 3135 dasd_device_operations = { 3136 .owner = THIS_MODULE, 3137 .open = dasd_open, 3138 .release = dasd_release, 3139 .ioctl = dasd_ioctl, 3140 .compat_ioctl = dasd_ioctl, 3141 .getgeo = dasd_getgeo, 3142 }; 3143 3144 /******************************************************************************* 3145 * end of block device operations 3146 */ 3147 3148 static void 3149 dasd_exit(void) 3150 { 3151 #ifdef CONFIG_PROC_FS 3152 dasd_proc_exit(); 3153 #endif 3154 dasd_eer_exit(); 3155 if (dasd_page_cache != NULL) { 3156 kmem_cache_destroy(dasd_page_cache); 3157 dasd_page_cache = NULL; 3158 } 3159 dasd_gendisk_exit(); 3160 dasd_devmap_exit(); 3161 if (dasd_debug_area != NULL) { 3162 debug_unregister(dasd_debug_area); 3163 dasd_debug_area = NULL; 3164 } 3165 dasd_statistics_removeroot(); 3166 } 3167 3168 /* 3169 * SECTION: common functions for ccw_driver use 3170 */ 3171 3172 /* 3173 * Is the device read-only? 3174 * Note that this function does not report the setting of the 3175 * readonly device attribute, but how it is configured in z/VM. 3176 */ 3177 int dasd_device_is_ro(struct dasd_device *device) 3178 { 3179 struct ccw_dev_id dev_id; 3180 struct diag210 diag_data; 3181 int rc; 3182 3183 if (!MACHINE_IS_VM) 3184 return 0; 3185 ccw_device_get_id(device->cdev, &dev_id); 3186 memset(&diag_data, 0, sizeof(diag_data)); 3187 diag_data.vrdcdvno = dev_id.devno; 3188 diag_data.vrdclen = sizeof(diag_data); 3189 rc = diag210(&diag_data); 3190 if (rc == 0 || rc == 2) { 3191 return diag_data.vrdcvfla & 0x80; 3192 } else { 3193 DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d", 3194 dev_id.devno, rc); 3195 return 0; 3196 } 3197 } 3198 EXPORT_SYMBOL_GPL(dasd_device_is_ro); 3199 3200 static void dasd_generic_auto_online(void *data, async_cookie_t cookie) 3201 { 3202 struct ccw_device *cdev = data; 3203 int ret; 3204 3205 ret = ccw_device_set_online(cdev); 3206 if (ret) 3207 pr_warn("%s: Setting the DASD online failed with rc=%d\n", 3208 dev_name(&cdev->dev), ret); 3209 } 3210 3211 /* 3212 * Initial attempt at a probe function. this can be simplified once 3213 * the other detection code is gone. 3214 */ 3215 int dasd_generic_probe(struct ccw_device *cdev, 3216 struct dasd_discipline *discipline) 3217 { 3218 int ret; 3219 3220 ret = dasd_add_sysfs_files(cdev); 3221 if (ret) { 3222 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s", 3223 "dasd_generic_probe: could not add " 3224 "sysfs entries"); 3225 return ret; 3226 } 3227 cdev->handler = &dasd_int_handler; 3228 3229 /* 3230 * Automatically online either all dasd devices (dasd_autodetect) 3231 * or all devices specified with dasd= parameters during 3232 * initial probe. 3233 */ 3234 if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) || 3235 (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0)) 3236 async_schedule(dasd_generic_auto_online, cdev); 3237 return 0; 3238 } 3239 EXPORT_SYMBOL_GPL(dasd_generic_probe); 3240 3241 /* 3242 * This will one day be called from a global not_oper handler. 3243 * It is also used by driver_unregister during module unload. 3244 */ 3245 void dasd_generic_remove(struct ccw_device *cdev) 3246 { 3247 struct dasd_device *device; 3248 struct dasd_block *block; 3249 3250 cdev->handler = NULL; 3251 3252 device = dasd_device_from_cdev(cdev); 3253 if (IS_ERR(device)) { 3254 dasd_remove_sysfs_files(cdev); 3255 return; 3256 } 3257 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags) && 3258 !test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) { 3259 /* Already doing offline processing */ 3260 dasd_put_device(device); 3261 dasd_remove_sysfs_files(cdev); 3262 return; 3263 } 3264 /* 3265 * This device is removed unconditionally. Set offline 3266 * flag to prevent dasd_open from opening it while it is 3267 * no quite down yet. 3268 */ 3269 dasd_set_target_state(device, DASD_STATE_NEW); 3270 /* dasd_delete_device destroys the device reference. */ 3271 block = device->block; 3272 dasd_delete_device(device); 3273 /* 3274 * life cycle of block is bound to device, so delete it after 3275 * device was safely removed 3276 */ 3277 if (block) 3278 dasd_free_block(block); 3279 3280 dasd_remove_sysfs_files(cdev); 3281 } 3282 EXPORT_SYMBOL_GPL(dasd_generic_remove); 3283 3284 /* 3285 * Activate a device. This is called from dasd_{eckd,fba}_probe() when either 3286 * the device is detected for the first time and is supposed to be used 3287 * or the user has started activation through sysfs. 3288 */ 3289 int dasd_generic_set_online(struct ccw_device *cdev, 3290 struct dasd_discipline *base_discipline) 3291 { 3292 struct dasd_discipline *discipline; 3293 struct dasd_device *device; 3294 int rc; 3295 3296 /* first online clears initial online feature flag */ 3297 dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0); 3298 device = dasd_create_device(cdev); 3299 if (IS_ERR(device)) 3300 return PTR_ERR(device); 3301 3302 discipline = base_discipline; 3303 if (device->features & DASD_FEATURE_USEDIAG) { 3304 if (!dasd_diag_discipline_pointer) { 3305 /* Try to load the required module. */ 3306 rc = request_module(DASD_DIAG_MOD); 3307 if (rc) { 3308 pr_warn("%s Setting the DASD online failed " 3309 "because the required module %s " 3310 "could not be loaded (rc=%d)\n", 3311 dev_name(&cdev->dev), DASD_DIAG_MOD, 3312 rc); 3313 dasd_delete_device(device); 3314 return -ENODEV; 3315 } 3316 } 3317 /* Module init could have failed, so check again here after 3318 * request_module(). */ 3319 if (!dasd_diag_discipline_pointer) { 3320 pr_warn("%s Setting the DASD online failed because of missing DIAG discipline\n", 3321 dev_name(&cdev->dev)); 3322 dasd_delete_device(device); 3323 return -ENODEV; 3324 } 3325 discipline = dasd_diag_discipline_pointer; 3326 } 3327 if (!try_module_get(base_discipline->owner)) { 3328 dasd_delete_device(device); 3329 return -EINVAL; 3330 } 3331 if (!try_module_get(discipline->owner)) { 3332 module_put(base_discipline->owner); 3333 dasd_delete_device(device); 3334 return -EINVAL; 3335 } 3336 device->base_discipline = base_discipline; 3337 device->discipline = discipline; 3338 3339 /* check_device will allocate block device if necessary */ 3340 rc = discipline->check_device(device); 3341 if (rc) { 3342 pr_warn("%s Setting the DASD online with discipline %s failed with rc=%i\n", 3343 dev_name(&cdev->dev), discipline->name, rc); 3344 module_put(discipline->owner); 3345 module_put(base_discipline->owner); 3346 dasd_delete_device(device); 3347 return rc; 3348 } 3349 3350 dasd_set_target_state(device, DASD_STATE_ONLINE); 3351 if (device->state <= DASD_STATE_KNOWN) { 3352 pr_warn("%s Setting the DASD online failed because of a missing discipline\n", 3353 dev_name(&cdev->dev)); 3354 rc = -ENODEV; 3355 dasd_set_target_state(device, DASD_STATE_NEW); 3356 if (device->block) 3357 dasd_free_block(device->block); 3358 dasd_delete_device(device); 3359 } else 3360 pr_debug("dasd_generic device %s found\n", 3361 dev_name(&cdev->dev)); 3362 3363 wait_event(dasd_init_waitq, _wait_for_device(device)); 3364 3365 dasd_put_device(device); 3366 return rc; 3367 } 3368 EXPORT_SYMBOL_GPL(dasd_generic_set_online); 3369 3370 int dasd_generic_set_offline(struct ccw_device *cdev) 3371 { 3372 struct dasd_device *device; 3373 struct dasd_block *block; 3374 int max_count, open_count, rc; 3375 3376 rc = 0; 3377 device = dasd_device_from_cdev(cdev); 3378 if (IS_ERR(device)) 3379 return PTR_ERR(device); 3380 3381 /* 3382 * We must make sure that this device is currently not in use. 3383 * The open_count is increased for every opener, that includes 3384 * the blkdev_get in dasd_scan_partitions. We are only interested 3385 * in the other openers. 3386 */ 3387 if (device->block) { 3388 max_count = device->block->bdev ? 0 : -1; 3389 open_count = atomic_read(&device->block->open_count); 3390 if (open_count > max_count) { 3391 if (open_count > 0) 3392 pr_warn("%s: The DASD cannot be set offline with open count %i\n", 3393 dev_name(&cdev->dev), open_count); 3394 else 3395 pr_warn("%s: The DASD cannot be set offline while it is in use\n", 3396 dev_name(&cdev->dev)); 3397 clear_bit(DASD_FLAG_OFFLINE, &device->flags); 3398 dasd_put_device(device); 3399 return -EBUSY; 3400 } 3401 } 3402 3403 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) { 3404 /* 3405 * safe offline already running 3406 * could only be called by normal offline so safe_offline flag 3407 * needs to be removed to run normal offline and kill all I/O 3408 */ 3409 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) { 3410 /* Already doing normal offline processing */ 3411 dasd_put_device(device); 3412 return -EBUSY; 3413 } else 3414 clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags); 3415 3416 } else 3417 if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) { 3418 /* Already doing offline processing */ 3419 dasd_put_device(device); 3420 return -EBUSY; 3421 } 3422 3423 /* 3424 * if safe_offline called set safe_offline_running flag and 3425 * clear safe_offline so that a call to normal offline 3426 * can overrun safe_offline processing 3427 */ 3428 if (test_and_clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags) && 3429 !test_and_set_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) { 3430 /* 3431 * If we want to set the device safe offline all IO operations 3432 * should be finished before continuing the offline process 3433 * so sync bdev first and then wait for our queues to become 3434 * empty 3435 */ 3436 /* sync blockdev and partitions */ 3437 rc = fsync_bdev(device->block->bdev); 3438 if (rc != 0) 3439 goto interrupted; 3440 3441 /* schedule device tasklet and wait for completion */ 3442 dasd_schedule_device_bh(device); 3443 rc = wait_event_interruptible(shutdown_waitq, 3444 _wait_for_empty_queues(device)); 3445 if (rc != 0) 3446 goto interrupted; 3447 } 3448 3449 set_bit(DASD_FLAG_OFFLINE, &device->flags); 3450 dasd_set_target_state(device, DASD_STATE_NEW); 3451 /* dasd_delete_device destroys the device reference. */ 3452 block = device->block; 3453 dasd_delete_device(device); 3454 /* 3455 * life cycle of block is bound to device, so delete it after 3456 * device was safely removed 3457 */ 3458 if (block) 3459 dasd_free_block(block); 3460 return 0; 3461 3462 interrupted: 3463 /* interrupted by signal */ 3464 clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags); 3465 clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags); 3466 clear_bit(DASD_FLAG_OFFLINE, &device->flags); 3467 dasd_put_device(device); 3468 return rc; 3469 } 3470 EXPORT_SYMBOL_GPL(dasd_generic_set_offline); 3471 3472 int dasd_generic_last_path_gone(struct dasd_device *device) 3473 { 3474 struct dasd_ccw_req *cqr; 3475 3476 dev_warn(&device->cdev->dev, "No operational channel path is left " 3477 "for the device\n"); 3478 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone"); 3479 /* First of all call extended error reporting. */ 3480 dasd_eer_write(device, NULL, DASD_EER_NOPATH); 3481 3482 if (device->state < DASD_STATE_BASIC) 3483 return 0; 3484 /* Device is active. We want to keep it. */ 3485 list_for_each_entry(cqr, &device->ccw_queue, devlist) 3486 if ((cqr->status == DASD_CQR_IN_IO) || 3487 (cqr->status == DASD_CQR_CLEAR_PENDING)) { 3488 cqr->status = DASD_CQR_QUEUED; 3489 cqr->retries++; 3490 } 3491 dasd_device_set_stop_bits(device, DASD_STOPPED_DC_WAIT); 3492 dasd_device_clear_timer(device); 3493 dasd_schedule_device_bh(device); 3494 return 1; 3495 } 3496 EXPORT_SYMBOL_GPL(dasd_generic_last_path_gone); 3497 3498 int dasd_generic_path_operational(struct dasd_device *device) 3499 { 3500 dev_info(&device->cdev->dev, "A channel path to the device has become " 3501 "operational\n"); 3502 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "path operational"); 3503 dasd_device_remove_stop_bits(device, DASD_STOPPED_DC_WAIT); 3504 if (device->stopped & DASD_UNRESUMED_PM) { 3505 dasd_device_remove_stop_bits(device, DASD_UNRESUMED_PM); 3506 dasd_restore_device(device); 3507 return 1; 3508 } 3509 dasd_schedule_device_bh(device); 3510 if (device->block) 3511 dasd_schedule_block_bh(device->block); 3512 3513 if (!device->stopped) 3514 wake_up(&generic_waitq); 3515 3516 return 1; 3517 } 3518 EXPORT_SYMBOL_GPL(dasd_generic_path_operational); 3519 3520 int dasd_generic_notify(struct ccw_device *cdev, int event) 3521 { 3522 struct dasd_device *device; 3523 int ret; 3524 3525 device = dasd_device_from_cdev_locked(cdev); 3526 if (IS_ERR(device)) 3527 return 0; 3528 ret = 0; 3529 switch (event) { 3530 case CIO_GONE: 3531 case CIO_BOXED: 3532 case CIO_NO_PATH: 3533 device->path_data.opm = 0; 3534 device->path_data.ppm = 0; 3535 device->path_data.npm = 0; 3536 ret = dasd_generic_last_path_gone(device); 3537 break; 3538 case CIO_OPER: 3539 ret = 1; 3540 if (device->path_data.opm) 3541 ret = dasd_generic_path_operational(device); 3542 break; 3543 } 3544 dasd_put_device(device); 3545 return ret; 3546 } 3547 EXPORT_SYMBOL_GPL(dasd_generic_notify); 3548 3549 void dasd_generic_path_event(struct ccw_device *cdev, int *path_event) 3550 { 3551 int chp; 3552 __u8 oldopm, eventlpm; 3553 struct dasd_device *device; 3554 3555 device = dasd_device_from_cdev_locked(cdev); 3556 if (IS_ERR(device)) 3557 return; 3558 for (chp = 0; chp < 8; chp++) { 3559 eventlpm = 0x80 >> chp; 3560 if (path_event[chp] & PE_PATH_GONE) { 3561 oldopm = device->path_data.opm; 3562 device->path_data.opm &= ~eventlpm; 3563 device->path_data.ppm &= ~eventlpm; 3564 device->path_data.npm &= ~eventlpm; 3565 if (oldopm && !device->path_data.opm) { 3566 dev_warn(&device->cdev->dev, 3567 "No verified channel paths remain " 3568 "for the device\n"); 3569 DBF_DEV_EVENT(DBF_WARNING, device, 3570 "%s", "last verified path gone"); 3571 dasd_eer_write(device, NULL, DASD_EER_NOPATH); 3572 dasd_device_set_stop_bits(device, 3573 DASD_STOPPED_DC_WAIT); 3574 } 3575 } 3576 if (path_event[chp] & PE_PATH_AVAILABLE) { 3577 device->path_data.opm &= ~eventlpm; 3578 device->path_data.ppm &= ~eventlpm; 3579 device->path_data.npm &= ~eventlpm; 3580 device->path_data.tbvpm |= eventlpm; 3581 dasd_schedule_device_bh(device); 3582 } 3583 if (path_event[chp] & PE_PATHGROUP_ESTABLISHED) { 3584 if (!(device->path_data.opm & eventlpm) && 3585 !(device->path_data.tbvpm & eventlpm)) { 3586 /* 3587 * we can not establish a pathgroup on an 3588 * unavailable path, so trigger a path 3589 * verification first 3590 */ 3591 device->path_data.tbvpm |= eventlpm; 3592 dasd_schedule_device_bh(device); 3593 } 3594 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 3595 "Pathgroup re-established\n"); 3596 if (device->discipline->kick_validate) 3597 device->discipline->kick_validate(device); 3598 } 3599 } 3600 dasd_put_device(device); 3601 } 3602 EXPORT_SYMBOL_GPL(dasd_generic_path_event); 3603 3604 int dasd_generic_verify_path(struct dasd_device *device, __u8 lpm) 3605 { 3606 if (!device->path_data.opm && lpm) { 3607 device->path_data.opm = lpm; 3608 dasd_generic_path_operational(device); 3609 } else 3610 device->path_data.opm |= lpm; 3611 return 0; 3612 } 3613 EXPORT_SYMBOL_GPL(dasd_generic_verify_path); 3614 3615 3616 int dasd_generic_pm_freeze(struct ccw_device *cdev) 3617 { 3618 struct dasd_device *device = dasd_device_from_cdev(cdev); 3619 struct list_head freeze_queue; 3620 struct dasd_ccw_req *cqr, *n; 3621 struct dasd_ccw_req *refers; 3622 int rc; 3623 3624 if (IS_ERR(device)) 3625 return PTR_ERR(device); 3626 3627 /* mark device as suspended */ 3628 set_bit(DASD_FLAG_SUSPENDED, &device->flags); 3629 3630 if (device->discipline->freeze) 3631 rc = device->discipline->freeze(device); 3632 3633 /* disallow new I/O */ 3634 dasd_device_set_stop_bits(device, DASD_STOPPED_PM); 3635 3636 /* clear active requests and requeue them to block layer if possible */ 3637 INIT_LIST_HEAD(&freeze_queue); 3638 spin_lock_irq(get_ccwdev_lock(cdev)); 3639 rc = 0; 3640 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) { 3641 /* Check status and move request to flush_queue */ 3642 if (cqr->status == DASD_CQR_IN_IO) { 3643 rc = device->discipline->term_IO(cqr); 3644 if (rc) { 3645 /* unable to terminate requeust */ 3646 dev_err(&device->cdev->dev, 3647 "Unable to terminate request %p " 3648 "on suspend\n", cqr); 3649 spin_unlock_irq(get_ccwdev_lock(cdev)); 3650 dasd_put_device(device); 3651 return rc; 3652 } 3653 } 3654 list_move_tail(&cqr->devlist, &freeze_queue); 3655 } 3656 spin_unlock_irq(get_ccwdev_lock(cdev)); 3657 3658 list_for_each_entry_safe(cqr, n, &freeze_queue, devlist) { 3659 wait_event(dasd_flush_wq, 3660 (cqr->status != DASD_CQR_CLEAR_PENDING)); 3661 if (cqr->status == DASD_CQR_CLEARED) 3662 cqr->status = DASD_CQR_QUEUED; 3663 3664 /* requeue requests to blocklayer will only work for 3665 block device requests */ 3666 if (_dasd_requeue_request(cqr)) 3667 continue; 3668 3669 /* remove requests from device and block queue */ 3670 list_del_init(&cqr->devlist); 3671 while (cqr->refers != NULL) { 3672 refers = cqr->refers; 3673 /* remove the request from the block queue */ 3674 list_del(&cqr->blocklist); 3675 /* free the finished erp request */ 3676 dasd_free_erp_request(cqr, cqr->memdev); 3677 cqr = refers; 3678 } 3679 if (cqr->block) 3680 list_del_init(&cqr->blocklist); 3681 cqr->block->base->discipline->free_cp( 3682 cqr, (struct request *) cqr->callback_data); 3683 } 3684 3685 /* 3686 * if requests remain then they are internal request 3687 * and go back to the device queue 3688 */ 3689 if (!list_empty(&freeze_queue)) { 3690 /* move freeze_queue to start of the ccw_queue */ 3691 spin_lock_irq(get_ccwdev_lock(cdev)); 3692 list_splice_tail(&freeze_queue, &device->ccw_queue); 3693 spin_unlock_irq(get_ccwdev_lock(cdev)); 3694 } 3695 dasd_put_device(device); 3696 return rc; 3697 } 3698 EXPORT_SYMBOL_GPL(dasd_generic_pm_freeze); 3699 3700 int dasd_generic_restore_device(struct ccw_device *cdev) 3701 { 3702 struct dasd_device *device = dasd_device_from_cdev(cdev); 3703 int rc = 0; 3704 3705 if (IS_ERR(device)) 3706 return PTR_ERR(device); 3707 3708 /* allow new IO again */ 3709 dasd_device_remove_stop_bits(device, 3710 (DASD_STOPPED_PM | DASD_UNRESUMED_PM)); 3711 3712 dasd_schedule_device_bh(device); 3713 3714 /* 3715 * call discipline restore function 3716 * if device is stopped do nothing e.g. for disconnected devices 3717 */ 3718 if (device->discipline->restore && !(device->stopped)) 3719 rc = device->discipline->restore(device); 3720 if (rc || device->stopped) 3721 /* 3722 * if the resume failed for the DASD we put it in 3723 * an UNRESUMED stop state 3724 */ 3725 device->stopped |= DASD_UNRESUMED_PM; 3726 3727 if (device->block) 3728 dasd_schedule_block_bh(device->block); 3729 3730 clear_bit(DASD_FLAG_SUSPENDED, &device->flags); 3731 dasd_put_device(device); 3732 return 0; 3733 } 3734 EXPORT_SYMBOL_GPL(dasd_generic_restore_device); 3735 3736 static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device, 3737 void *rdc_buffer, 3738 int rdc_buffer_size, 3739 int magic) 3740 { 3741 struct dasd_ccw_req *cqr; 3742 struct ccw1 *ccw; 3743 unsigned long *idaw; 3744 3745 cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device); 3746 3747 if (IS_ERR(cqr)) { 3748 /* internal error 13 - Allocating the RDC request failed*/ 3749 dev_err(&device->cdev->dev, 3750 "An error occurred in the DASD device driver, " 3751 "reason=%s\n", "13"); 3752 return cqr; 3753 } 3754 3755 ccw = cqr->cpaddr; 3756 ccw->cmd_code = CCW_CMD_RDC; 3757 if (idal_is_needed(rdc_buffer, rdc_buffer_size)) { 3758 idaw = (unsigned long *) (cqr->data); 3759 ccw->cda = (__u32)(addr_t) idaw; 3760 ccw->flags = CCW_FLAG_IDA; 3761 idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size); 3762 } else { 3763 ccw->cda = (__u32)(addr_t) rdc_buffer; 3764 ccw->flags = 0; 3765 } 3766 3767 ccw->count = rdc_buffer_size; 3768 cqr->startdev = device; 3769 cqr->memdev = device; 3770 cqr->expires = 10*HZ; 3771 cqr->retries = 256; 3772 cqr->buildclk = get_tod_clock(); 3773 cqr->status = DASD_CQR_FILLED; 3774 return cqr; 3775 } 3776 3777 3778 int dasd_generic_read_dev_chars(struct dasd_device *device, int magic, 3779 void *rdc_buffer, int rdc_buffer_size) 3780 { 3781 int ret; 3782 struct dasd_ccw_req *cqr; 3783 3784 cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size, 3785 magic); 3786 if (IS_ERR(cqr)) 3787 return PTR_ERR(cqr); 3788 3789 ret = dasd_sleep_on(cqr); 3790 dasd_sfree_request(cqr, cqr->memdev); 3791 return ret; 3792 } 3793 EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars); 3794 3795 /* 3796 * In command mode and transport mode we need to look for sense 3797 * data in different places. The sense data itself is allways 3798 * an array of 32 bytes, so we can unify the sense data access 3799 * for both modes. 3800 */ 3801 char *dasd_get_sense(struct irb *irb) 3802 { 3803 struct tsb *tsb = NULL; 3804 char *sense = NULL; 3805 3806 if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) { 3807 if (irb->scsw.tm.tcw) 3808 tsb = tcw_get_tsb((struct tcw *)(unsigned long) 3809 irb->scsw.tm.tcw); 3810 if (tsb && tsb->length == 64 && tsb->flags) 3811 switch (tsb->flags & 0x07) { 3812 case 1: /* tsa_iostat */ 3813 sense = tsb->tsa.iostat.sense; 3814 break; 3815 case 2: /* tsa_ddpc */ 3816 sense = tsb->tsa.ddpc.sense; 3817 break; 3818 default: 3819 /* currently we don't use interrogate data */ 3820 break; 3821 } 3822 } else if (irb->esw.esw0.erw.cons) { 3823 sense = irb->ecw; 3824 } 3825 return sense; 3826 } 3827 EXPORT_SYMBOL_GPL(dasd_get_sense); 3828 3829 void dasd_generic_shutdown(struct ccw_device *cdev) 3830 { 3831 struct dasd_device *device; 3832 3833 device = dasd_device_from_cdev(cdev); 3834 if (IS_ERR(device)) 3835 return; 3836 3837 if (device->block) 3838 dasd_schedule_block_bh(device->block); 3839 3840 dasd_schedule_device_bh(device); 3841 3842 wait_event(shutdown_waitq, _wait_for_empty_queues(device)); 3843 } 3844 EXPORT_SYMBOL_GPL(dasd_generic_shutdown); 3845 3846 static int __init dasd_init(void) 3847 { 3848 int rc; 3849 3850 init_waitqueue_head(&dasd_init_waitq); 3851 init_waitqueue_head(&dasd_flush_wq); 3852 init_waitqueue_head(&generic_waitq); 3853 init_waitqueue_head(&shutdown_waitq); 3854 3855 /* register 'common' DASD debug area, used for all DBF_XXX calls */ 3856 dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long)); 3857 if (dasd_debug_area == NULL) { 3858 rc = -ENOMEM; 3859 goto failed; 3860 } 3861 debug_register_view(dasd_debug_area, &debug_sprintf_view); 3862 debug_set_level(dasd_debug_area, DBF_WARNING); 3863 3864 DBF_EVENT(DBF_EMERG, "%s", "debug area created"); 3865 3866 dasd_diag_discipline_pointer = NULL; 3867 3868 dasd_statistics_createroot(); 3869 3870 rc = dasd_devmap_init(); 3871 if (rc) 3872 goto failed; 3873 rc = dasd_gendisk_init(); 3874 if (rc) 3875 goto failed; 3876 rc = dasd_parse(); 3877 if (rc) 3878 goto failed; 3879 rc = dasd_eer_init(); 3880 if (rc) 3881 goto failed; 3882 #ifdef CONFIG_PROC_FS 3883 rc = dasd_proc_init(); 3884 if (rc) 3885 goto failed; 3886 #endif 3887 3888 return 0; 3889 failed: 3890 pr_info("The DASD device driver could not be initialized\n"); 3891 dasd_exit(); 3892 return rc; 3893 } 3894 3895 module_init(dasd_init); 3896 module_exit(dasd_exit); 3897