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 /* 42 * SECTION: exported variables of dasd.c 43 */ 44 debug_info_t *dasd_debug_area; 45 static struct dentry *dasd_debugfs_root_entry; 46 struct dasd_discipline *dasd_diag_discipline_pointer; 47 void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *); 48 49 MODULE_AUTHOR("Holger Smolinski <Holger.Smolinski@de.ibm.com>"); 50 MODULE_DESCRIPTION("Linux on S/390 DASD device driver," 51 " Copyright IBM Corp. 2000"); 52 MODULE_SUPPORTED_DEVICE("dasd"); 53 MODULE_LICENSE("GPL"); 54 55 /* 56 * SECTION: prototypes for static functions of dasd.c 57 */ 58 static int dasd_alloc_queue(struct dasd_block *); 59 static void dasd_setup_queue(struct dasd_block *); 60 static void dasd_free_queue(struct dasd_block *); 61 static void dasd_flush_request_queue(struct dasd_block *); 62 static int dasd_flush_block_queue(struct dasd_block *); 63 static void dasd_device_tasklet(struct dasd_device *); 64 static void dasd_block_tasklet(struct dasd_block *); 65 static void do_kick_device(struct work_struct *); 66 static void do_restore_device(struct work_struct *); 67 static void do_reload_device(struct work_struct *); 68 static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *); 69 static void dasd_device_timeout(unsigned long); 70 static void dasd_block_timeout(unsigned long); 71 static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *); 72 static void dasd_profile_init(struct dasd_profile *, struct dentry *); 73 static void dasd_profile_exit(struct dasd_profile *); 74 75 /* 76 * SECTION: Operations on the device structure. 77 */ 78 static wait_queue_head_t dasd_init_waitq; 79 static wait_queue_head_t dasd_flush_wq; 80 static wait_queue_head_t generic_waitq; 81 static wait_queue_head_t shutdown_waitq; 82 83 /* 84 * Allocate memory for a new device structure. 85 */ 86 struct dasd_device *dasd_alloc_device(void) 87 { 88 struct dasd_device *device; 89 90 device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC); 91 if (!device) 92 return ERR_PTR(-ENOMEM); 93 94 /* Get two pages for normal block device operations. */ 95 device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1); 96 if (!device->ccw_mem) { 97 kfree(device); 98 return ERR_PTR(-ENOMEM); 99 } 100 /* Get one page for error recovery. */ 101 device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA); 102 if (!device->erp_mem) { 103 free_pages((unsigned long) device->ccw_mem, 1); 104 kfree(device); 105 return ERR_PTR(-ENOMEM); 106 } 107 108 dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2); 109 dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE); 110 spin_lock_init(&device->mem_lock); 111 atomic_set(&device->tasklet_scheduled, 0); 112 tasklet_init(&device->tasklet, 113 (void (*)(unsigned long)) dasd_device_tasklet, 114 (unsigned long) device); 115 INIT_LIST_HEAD(&device->ccw_queue); 116 init_timer(&device->timer); 117 device->timer.function = dasd_device_timeout; 118 device->timer.data = (unsigned long) device; 119 INIT_WORK(&device->kick_work, do_kick_device); 120 INIT_WORK(&device->restore_device, do_restore_device); 121 INIT_WORK(&device->reload_device, do_reload_device); 122 device->state = DASD_STATE_NEW; 123 device->target = DASD_STATE_NEW; 124 mutex_init(&device->state_mutex); 125 spin_lock_init(&device->profile.lock); 126 return device; 127 } 128 129 /* 130 * Free memory of a device structure. 131 */ 132 void dasd_free_device(struct dasd_device *device) 133 { 134 kfree(device->private); 135 free_page((unsigned long) device->erp_mem); 136 free_pages((unsigned long) device->ccw_mem, 1); 137 kfree(device); 138 } 139 140 /* 141 * Allocate memory for a new device structure. 142 */ 143 struct dasd_block *dasd_alloc_block(void) 144 { 145 struct dasd_block *block; 146 147 block = kzalloc(sizeof(*block), GFP_ATOMIC); 148 if (!block) 149 return ERR_PTR(-ENOMEM); 150 /* open_count = 0 means device online but not in use */ 151 atomic_set(&block->open_count, -1); 152 153 spin_lock_init(&block->request_queue_lock); 154 atomic_set(&block->tasklet_scheduled, 0); 155 tasklet_init(&block->tasklet, 156 (void (*)(unsigned long)) dasd_block_tasklet, 157 (unsigned long) block); 158 INIT_LIST_HEAD(&block->ccw_queue); 159 spin_lock_init(&block->queue_lock); 160 init_timer(&block->timer); 161 block->timer.function = dasd_block_timeout; 162 block->timer.data = (unsigned long) block; 163 spin_lock_init(&block->profile.lock); 164 165 return block; 166 } 167 168 /* 169 * Free memory of a device structure. 170 */ 171 void dasd_free_block(struct dasd_block *block) 172 { 173 kfree(block); 174 } 175 176 /* 177 * Make a new device known to the system. 178 */ 179 static int dasd_state_new_to_known(struct dasd_device *device) 180 { 181 int rc; 182 183 /* 184 * As long as the device is not in state DASD_STATE_NEW we want to 185 * keep the reference count > 0. 186 */ 187 dasd_get_device(device); 188 189 if (device->block) { 190 rc = dasd_alloc_queue(device->block); 191 if (rc) { 192 dasd_put_device(device); 193 return rc; 194 } 195 } 196 device->state = DASD_STATE_KNOWN; 197 return 0; 198 } 199 200 /* 201 * Let the system forget about a device. 202 */ 203 static int dasd_state_known_to_new(struct dasd_device *device) 204 { 205 /* Disable extended error reporting for this device. */ 206 dasd_eer_disable(device); 207 /* Forget the discipline information. */ 208 if (device->discipline) { 209 if (device->discipline->uncheck_device) 210 device->discipline->uncheck_device(device); 211 module_put(device->discipline->owner); 212 } 213 device->discipline = NULL; 214 if (device->base_discipline) 215 module_put(device->base_discipline->owner); 216 device->base_discipline = NULL; 217 device->state = DASD_STATE_NEW; 218 219 if (device->block) 220 dasd_free_queue(device->block); 221 222 /* Give up reference we took in dasd_state_new_to_known. */ 223 dasd_put_device(device); 224 return 0; 225 } 226 227 static struct dentry *dasd_debugfs_setup(const char *name, 228 struct dentry *base_dentry) 229 { 230 struct dentry *pde; 231 232 if (!base_dentry) 233 return NULL; 234 pde = debugfs_create_dir(name, base_dentry); 235 if (!pde || IS_ERR(pde)) 236 return NULL; 237 return pde; 238 } 239 240 /* 241 * Request the irq line for the device. 242 */ 243 static int dasd_state_known_to_basic(struct dasd_device *device) 244 { 245 struct dasd_block *block = device->block; 246 int rc = 0; 247 248 /* Allocate and register gendisk structure. */ 249 if (block) { 250 rc = dasd_gendisk_alloc(block); 251 if (rc) 252 return rc; 253 block->debugfs_dentry = 254 dasd_debugfs_setup(block->gdp->disk_name, 255 dasd_debugfs_root_entry); 256 dasd_profile_init(&block->profile, block->debugfs_dentry); 257 if (dasd_global_profile_level == DASD_PROFILE_ON) 258 dasd_profile_on(&device->block->profile); 259 } 260 device->debugfs_dentry = 261 dasd_debugfs_setup(dev_name(&device->cdev->dev), 262 dasd_debugfs_root_entry); 263 dasd_profile_init(&device->profile, device->debugfs_dentry); 264 265 /* register 'device' debug area, used for all DBF_DEV_XXX calls */ 266 device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1, 267 8 * sizeof(long)); 268 debug_register_view(device->debug_area, &debug_sprintf_view); 269 debug_set_level(device->debug_area, DBF_WARNING); 270 DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created"); 271 272 device->state = DASD_STATE_BASIC; 273 274 return rc; 275 } 276 277 /* 278 * Release the irq line for the device. Terminate any running i/o. 279 */ 280 static int dasd_state_basic_to_known(struct dasd_device *device) 281 { 282 int rc; 283 284 if (device->block) { 285 dasd_profile_exit(&device->block->profile); 286 if (device->block->debugfs_dentry) 287 debugfs_remove(device->block->debugfs_dentry); 288 dasd_gendisk_free(device->block); 289 dasd_block_clear_timer(device->block); 290 } 291 rc = dasd_flush_device_queue(device); 292 if (rc) 293 return rc; 294 dasd_device_clear_timer(device); 295 dasd_profile_exit(&device->profile); 296 if (device->debugfs_dentry) 297 debugfs_remove(device->debugfs_dentry); 298 299 DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device); 300 if (device->debug_area != NULL) { 301 debug_unregister(device->debug_area); 302 device->debug_area = NULL; 303 } 304 device->state = DASD_STATE_KNOWN; 305 return 0; 306 } 307 308 /* 309 * Do the initial analysis. The do_analysis function may return 310 * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC 311 * until the discipline decides to continue the startup sequence 312 * by calling the function dasd_change_state. The eckd disciplines 313 * uses this to start a ccw that detects the format. The completion 314 * interrupt for this detection ccw uses the kernel event daemon to 315 * trigger the call to dasd_change_state. All this is done in the 316 * discipline code, see dasd_eckd.c. 317 * After the analysis ccw is done (do_analysis returned 0) the block 318 * device is setup. 319 * In case the analysis returns an error, the device setup is stopped 320 * (a fake disk was already added to allow formatting). 321 */ 322 static int dasd_state_basic_to_ready(struct dasd_device *device) 323 { 324 int rc; 325 struct dasd_block *block; 326 327 rc = 0; 328 block = device->block; 329 /* make disk known with correct capacity */ 330 if (block) { 331 if (block->base->discipline->do_analysis != NULL) 332 rc = block->base->discipline->do_analysis(block); 333 if (rc) { 334 if (rc != -EAGAIN) { 335 device->state = DASD_STATE_UNFMT; 336 goto out; 337 } 338 return rc; 339 } 340 dasd_setup_queue(block); 341 set_capacity(block->gdp, 342 block->blocks << block->s2b_shift); 343 device->state = DASD_STATE_READY; 344 rc = dasd_scan_partitions(block); 345 if (rc) { 346 device->state = DASD_STATE_BASIC; 347 return rc; 348 } 349 } else { 350 device->state = DASD_STATE_READY; 351 } 352 out: 353 if (device->discipline->basic_to_ready) 354 rc = device->discipline->basic_to_ready(device); 355 return rc; 356 } 357 358 static inline 359 int _wait_for_empty_queues(struct dasd_device *device) 360 { 361 if (device->block) 362 return list_empty(&device->ccw_queue) && 363 list_empty(&device->block->ccw_queue); 364 else 365 return list_empty(&device->ccw_queue); 366 } 367 368 /* 369 * Remove device from block device layer. Destroy dirty buffers. 370 * Forget format information. Check if the target level is basic 371 * and if it is create fake disk for formatting. 372 */ 373 static int dasd_state_ready_to_basic(struct dasd_device *device) 374 { 375 int rc; 376 377 if (device->discipline->ready_to_basic) { 378 rc = device->discipline->ready_to_basic(device); 379 if (rc) 380 return rc; 381 } 382 device->state = DASD_STATE_BASIC; 383 if (device->block) { 384 struct dasd_block *block = device->block; 385 rc = dasd_flush_block_queue(block); 386 if (rc) { 387 device->state = DASD_STATE_READY; 388 return rc; 389 } 390 dasd_flush_request_queue(block); 391 dasd_destroy_partitions(block); 392 block->blocks = 0; 393 block->bp_block = 0; 394 block->s2b_shift = 0; 395 } 396 return 0; 397 } 398 399 /* 400 * Back to basic. 401 */ 402 static int dasd_state_unfmt_to_basic(struct dasd_device *device) 403 { 404 device->state = DASD_STATE_BASIC; 405 return 0; 406 } 407 408 /* 409 * Make the device online and schedule the bottom half to start 410 * the requeueing of requests from the linux request queue to the 411 * ccw queue. 412 */ 413 static int 414 dasd_state_ready_to_online(struct dasd_device * device) 415 { 416 struct gendisk *disk; 417 struct disk_part_iter piter; 418 struct hd_struct *part; 419 420 device->state = DASD_STATE_ONLINE; 421 if (device->block) { 422 dasd_schedule_block_bh(device->block); 423 if ((device->features & DASD_FEATURE_USERAW)) { 424 disk = device->block->gdp; 425 kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE); 426 return 0; 427 } 428 disk = device->block->bdev->bd_disk; 429 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0); 430 while ((part = disk_part_iter_next(&piter))) 431 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE); 432 disk_part_iter_exit(&piter); 433 } 434 return 0; 435 } 436 437 /* 438 * Stop the requeueing of requests again. 439 */ 440 static int dasd_state_online_to_ready(struct dasd_device *device) 441 { 442 int rc; 443 struct gendisk *disk; 444 struct disk_part_iter piter; 445 struct hd_struct *part; 446 447 if (device->discipline->online_to_ready) { 448 rc = device->discipline->online_to_ready(device); 449 if (rc) 450 return rc; 451 } 452 453 device->state = DASD_STATE_READY; 454 if (device->block && !(device->features & DASD_FEATURE_USERAW)) { 455 disk = device->block->bdev->bd_disk; 456 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0); 457 while ((part = disk_part_iter_next(&piter))) 458 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE); 459 disk_part_iter_exit(&piter); 460 } 461 return 0; 462 } 463 464 /* 465 * Device startup state changes. 466 */ 467 static int dasd_increase_state(struct dasd_device *device) 468 { 469 int rc; 470 471 rc = 0; 472 if (device->state == DASD_STATE_NEW && 473 device->target >= DASD_STATE_KNOWN) 474 rc = dasd_state_new_to_known(device); 475 476 if (!rc && 477 device->state == DASD_STATE_KNOWN && 478 device->target >= DASD_STATE_BASIC) 479 rc = dasd_state_known_to_basic(device); 480 481 if (!rc && 482 device->state == DASD_STATE_BASIC && 483 device->target >= DASD_STATE_READY) 484 rc = dasd_state_basic_to_ready(device); 485 486 if (!rc && 487 device->state == DASD_STATE_UNFMT && 488 device->target > DASD_STATE_UNFMT) 489 rc = -EPERM; 490 491 if (!rc && 492 device->state == DASD_STATE_READY && 493 device->target >= DASD_STATE_ONLINE) 494 rc = dasd_state_ready_to_online(device); 495 496 return rc; 497 } 498 499 /* 500 * Device shutdown state changes. 501 */ 502 static int dasd_decrease_state(struct dasd_device *device) 503 { 504 int rc; 505 506 rc = 0; 507 if (device->state == DASD_STATE_ONLINE && 508 device->target <= DASD_STATE_READY) 509 rc = dasd_state_online_to_ready(device); 510 511 if (!rc && 512 device->state == DASD_STATE_READY && 513 device->target <= DASD_STATE_BASIC) 514 rc = dasd_state_ready_to_basic(device); 515 516 if (!rc && 517 device->state == DASD_STATE_UNFMT && 518 device->target <= DASD_STATE_BASIC) 519 rc = dasd_state_unfmt_to_basic(device); 520 521 if (!rc && 522 device->state == DASD_STATE_BASIC && 523 device->target <= DASD_STATE_KNOWN) 524 rc = dasd_state_basic_to_known(device); 525 526 if (!rc && 527 device->state == DASD_STATE_KNOWN && 528 device->target <= DASD_STATE_NEW) 529 rc = dasd_state_known_to_new(device); 530 531 return rc; 532 } 533 534 /* 535 * This is the main startup/shutdown routine. 536 */ 537 static void dasd_change_state(struct dasd_device *device) 538 { 539 int rc; 540 541 if (device->state == device->target) 542 /* Already where we want to go today... */ 543 return; 544 if (device->state < device->target) 545 rc = dasd_increase_state(device); 546 else 547 rc = dasd_decrease_state(device); 548 if (rc == -EAGAIN) 549 return; 550 if (rc) 551 device->target = device->state; 552 553 /* let user-space know that the device status changed */ 554 kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE); 555 556 if (device->state == device->target) 557 wake_up(&dasd_init_waitq); 558 } 559 560 /* 561 * Kick starter for devices that did not complete the startup/shutdown 562 * procedure or were sleeping because of a pending state. 563 * dasd_kick_device will schedule a call do do_kick_device to the kernel 564 * event daemon. 565 */ 566 static void do_kick_device(struct work_struct *work) 567 { 568 struct dasd_device *device = container_of(work, struct dasd_device, kick_work); 569 mutex_lock(&device->state_mutex); 570 dasd_change_state(device); 571 mutex_unlock(&device->state_mutex); 572 dasd_schedule_device_bh(device); 573 dasd_put_device(device); 574 } 575 576 void dasd_kick_device(struct dasd_device *device) 577 { 578 dasd_get_device(device); 579 /* queue call to dasd_kick_device to the kernel event daemon. */ 580 schedule_work(&device->kick_work); 581 } 582 583 /* 584 * dasd_reload_device will schedule a call do do_reload_device to the kernel 585 * event daemon. 586 */ 587 static void do_reload_device(struct work_struct *work) 588 { 589 struct dasd_device *device = container_of(work, struct dasd_device, 590 reload_device); 591 device->discipline->reload(device); 592 dasd_put_device(device); 593 } 594 595 void dasd_reload_device(struct dasd_device *device) 596 { 597 dasd_get_device(device); 598 /* queue call to dasd_reload_device to the kernel event daemon. */ 599 schedule_work(&device->reload_device); 600 } 601 EXPORT_SYMBOL(dasd_reload_device); 602 603 /* 604 * dasd_restore_device will schedule a call do do_restore_device to the kernel 605 * event daemon. 606 */ 607 static void do_restore_device(struct work_struct *work) 608 { 609 struct dasd_device *device = container_of(work, struct dasd_device, 610 restore_device); 611 device->cdev->drv->restore(device->cdev); 612 dasd_put_device(device); 613 } 614 615 void dasd_restore_device(struct dasd_device *device) 616 { 617 dasd_get_device(device); 618 /* queue call to dasd_restore_device to the kernel event daemon. */ 619 schedule_work(&device->restore_device); 620 } 621 622 /* 623 * Set the target state for a device and starts the state change. 624 */ 625 void dasd_set_target_state(struct dasd_device *device, int target) 626 { 627 dasd_get_device(device); 628 mutex_lock(&device->state_mutex); 629 /* If we are in probeonly mode stop at DASD_STATE_READY. */ 630 if (dasd_probeonly && target > DASD_STATE_READY) 631 target = DASD_STATE_READY; 632 if (device->target != target) { 633 if (device->state == target) 634 wake_up(&dasd_init_waitq); 635 device->target = target; 636 } 637 if (device->state != device->target) 638 dasd_change_state(device); 639 mutex_unlock(&device->state_mutex); 640 dasd_put_device(device); 641 } 642 643 /* 644 * Enable devices with device numbers in [from..to]. 645 */ 646 static inline int _wait_for_device(struct dasd_device *device) 647 { 648 return (device->state == device->target); 649 } 650 651 void dasd_enable_device(struct dasd_device *device) 652 { 653 dasd_set_target_state(device, DASD_STATE_ONLINE); 654 if (device->state <= DASD_STATE_KNOWN) 655 /* No discipline for device found. */ 656 dasd_set_target_state(device, DASD_STATE_NEW); 657 /* Now wait for the devices to come up. */ 658 wait_event(dasd_init_waitq, _wait_for_device(device)); 659 660 dasd_reload_device(device); 661 if (device->discipline->kick_validate) 662 device->discipline->kick_validate(device); 663 } 664 665 /* 666 * SECTION: device operation (interrupt handler, start i/o, term i/o ...) 667 */ 668 669 unsigned int dasd_global_profile_level = DASD_PROFILE_OFF; 670 671 #ifdef CONFIG_DASD_PROFILE 672 struct dasd_profile_info dasd_global_profile_data; 673 static struct dentry *dasd_global_profile_dentry; 674 static struct dentry *dasd_debugfs_global_entry; 675 676 /* 677 * Add profiling information for cqr before execution. 678 */ 679 static void dasd_profile_start(struct dasd_block *block, 680 struct dasd_ccw_req *cqr, 681 struct request *req) 682 { 683 struct list_head *l; 684 unsigned int counter; 685 struct dasd_device *device; 686 687 /* count the length of the chanq for statistics */ 688 counter = 0; 689 if (dasd_global_profile_level || block->profile.data) 690 list_for_each(l, &block->ccw_queue) 691 if (++counter >= 31) 692 break; 693 694 if (dasd_global_profile_level) { 695 dasd_global_profile_data.dasd_io_nr_req[counter]++; 696 if (rq_data_dir(req) == READ) 697 dasd_global_profile_data.dasd_read_nr_req[counter]++; 698 } 699 700 spin_lock(&block->profile.lock); 701 if (block->profile.data) 702 block->profile.data->dasd_io_nr_req[counter]++; 703 if (rq_data_dir(req) == READ) 704 block->profile.data->dasd_read_nr_req[counter]++; 705 spin_unlock(&block->profile.lock); 706 707 /* 708 * We count the request for the start device, even though it may run on 709 * some other device due to error recovery. This way we make sure that 710 * we count each request only once. 711 */ 712 device = cqr->startdev; 713 if (device->profile.data) { 714 counter = 1; /* request is not yet queued on the start device */ 715 list_for_each(l, &device->ccw_queue) 716 if (++counter >= 31) 717 break; 718 } 719 spin_lock(&device->profile.lock); 720 if (device->profile.data) { 721 device->profile.data->dasd_io_nr_req[counter]++; 722 if (rq_data_dir(req) == READ) 723 device->profile.data->dasd_read_nr_req[counter]++; 724 } 725 spin_unlock(&device->profile.lock); 726 } 727 728 /* 729 * Add profiling information for cqr after execution. 730 */ 731 732 #define dasd_profile_counter(value, index) \ 733 { \ 734 for (index = 0; index < 31 && value >> (2+index); index++) \ 735 ; \ 736 } 737 738 static void dasd_profile_end_add_data(struct dasd_profile_info *data, 739 int is_alias, 740 int is_tpm, 741 int is_read, 742 long sectors, 743 int sectors_ind, 744 int tottime_ind, 745 int tottimeps_ind, 746 int strtime_ind, 747 int irqtime_ind, 748 int irqtimeps_ind, 749 int endtime_ind) 750 { 751 /* in case of an overflow, reset the whole profile */ 752 if (data->dasd_io_reqs == UINT_MAX) { 753 memset(data, 0, sizeof(*data)); 754 getnstimeofday(&data->starttod); 755 } 756 data->dasd_io_reqs++; 757 data->dasd_io_sects += sectors; 758 if (is_alias) 759 data->dasd_io_alias++; 760 if (is_tpm) 761 data->dasd_io_tpm++; 762 763 data->dasd_io_secs[sectors_ind]++; 764 data->dasd_io_times[tottime_ind]++; 765 data->dasd_io_timps[tottimeps_ind]++; 766 data->dasd_io_time1[strtime_ind]++; 767 data->dasd_io_time2[irqtime_ind]++; 768 data->dasd_io_time2ps[irqtimeps_ind]++; 769 data->dasd_io_time3[endtime_ind]++; 770 771 if (is_read) { 772 data->dasd_read_reqs++; 773 data->dasd_read_sects += sectors; 774 if (is_alias) 775 data->dasd_read_alias++; 776 if (is_tpm) 777 data->dasd_read_tpm++; 778 data->dasd_read_secs[sectors_ind]++; 779 data->dasd_read_times[tottime_ind]++; 780 data->dasd_read_time1[strtime_ind]++; 781 data->dasd_read_time2[irqtime_ind]++; 782 data->dasd_read_time3[endtime_ind]++; 783 } 784 } 785 786 static void dasd_profile_end(struct dasd_block *block, 787 struct dasd_ccw_req *cqr, 788 struct request *req) 789 { 790 long strtime, irqtime, endtime, tottime; /* in microseconds */ 791 long tottimeps, sectors; 792 struct dasd_device *device; 793 int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind; 794 int irqtime_ind, irqtimeps_ind, endtime_ind; 795 796 device = cqr->startdev; 797 if (!(dasd_global_profile_level || 798 block->profile.data || 799 device->profile.data)) 800 return; 801 802 sectors = blk_rq_sectors(req); 803 if (!cqr->buildclk || !cqr->startclk || 804 !cqr->stopclk || !cqr->endclk || 805 !sectors) 806 return; 807 808 strtime = ((cqr->startclk - cqr->buildclk) >> 12); 809 irqtime = ((cqr->stopclk - cqr->startclk) >> 12); 810 endtime = ((cqr->endclk - cqr->stopclk) >> 12); 811 tottime = ((cqr->endclk - cqr->buildclk) >> 12); 812 tottimeps = tottime / sectors; 813 814 dasd_profile_counter(sectors, sectors_ind); 815 dasd_profile_counter(tottime, tottime_ind); 816 dasd_profile_counter(tottimeps, tottimeps_ind); 817 dasd_profile_counter(strtime, strtime_ind); 818 dasd_profile_counter(irqtime, irqtime_ind); 819 dasd_profile_counter(irqtime / sectors, irqtimeps_ind); 820 dasd_profile_counter(endtime, endtime_ind); 821 822 if (dasd_global_profile_level) { 823 dasd_profile_end_add_data(&dasd_global_profile_data, 824 cqr->startdev != block->base, 825 cqr->cpmode == 1, 826 rq_data_dir(req) == READ, 827 sectors, sectors_ind, tottime_ind, 828 tottimeps_ind, strtime_ind, 829 irqtime_ind, irqtimeps_ind, 830 endtime_ind); 831 } 832 833 spin_lock(&block->profile.lock); 834 if (block->profile.data) 835 dasd_profile_end_add_data(block->profile.data, 836 cqr->startdev != block->base, 837 cqr->cpmode == 1, 838 rq_data_dir(req) == READ, 839 sectors, sectors_ind, tottime_ind, 840 tottimeps_ind, strtime_ind, 841 irqtime_ind, irqtimeps_ind, 842 endtime_ind); 843 spin_unlock(&block->profile.lock); 844 845 spin_lock(&device->profile.lock); 846 if (device->profile.data) 847 dasd_profile_end_add_data(device->profile.data, 848 cqr->startdev != block->base, 849 cqr->cpmode == 1, 850 rq_data_dir(req) == READ, 851 sectors, sectors_ind, tottime_ind, 852 tottimeps_ind, strtime_ind, 853 irqtime_ind, irqtimeps_ind, 854 endtime_ind); 855 spin_unlock(&device->profile.lock); 856 } 857 858 void dasd_profile_reset(struct dasd_profile *profile) 859 { 860 struct dasd_profile_info *data; 861 862 spin_lock_bh(&profile->lock); 863 data = profile->data; 864 if (!data) { 865 spin_unlock_bh(&profile->lock); 866 return; 867 } 868 memset(data, 0, sizeof(*data)); 869 getnstimeofday(&data->starttod); 870 spin_unlock_bh(&profile->lock); 871 } 872 873 void dasd_global_profile_reset(void) 874 { 875 memset(&dasd_global_profile_data, 0, sizeof(dasd_global_profile_data)); 876 getnstimeofday(&dasd_global_profile_data.starttod); 877 } 878 879 int dasd_profile_on(struct dasd_profile *profile) 880 { 881 struct dasd_profile_info *data; 882 883 data = kzalloc(sizeof(*data), GFP_KERNEL); 884 if (!data) 885 return -ENOMEM; 886 spin_lock_bh(&profile->lock); 887 if (profile->data) { 888 spin_unlock_bh(&profile->lock); 889 kfree(data); 890 return 0; 891 } 892 getnstimeofday(&data->starttod); 893 profile->data = data; 894 spin_unlock_bh(&profile->lock); 895 return 0; 896 } 897 898 void dasd_profile_off(struct dasd_profile *profile) 899 { 900 spin_lock_bh(&profile->lock); 901 kfree(profile->data); 902 profile->data = NULL; 903 spin_unlock_bh(&profile->lock); 904 } 905 906 char *dasd_get_user_string(const char __user *user_buf, size_t user_len) 907 { 908 char *buffer; 909 910 buffer = vmalloc(user_len + 1); 911 if (buffer == NULL) 912 return ERR_PTR(-ENOMEM); 913 if (copy_from_user(buffer, user_buf, user_len) != 0) { 914 vfree(buffer); 915 return ERR_PTR(-EFAULT); 916 } 917 /* got the string, now strip linefeed. */ 918 if (buffer[user_len - 1] == '\n') 919 buffer[user_len - 1] = 0; 920 else 921 buffer[user_len] = 0; 922 return buffer; 923 } 924 925 static ssize_t dasd_stats_write(struct file *file, 926 const char __user *user_buf, 927 size_t user_len, loff_t *pos) 928 { 929 char *buffer, *str; 930 int rc; 931 struct seq_file *m = (struct seq_file *)file->private_data; 932 struct dasd_profile *prof = m->private; 933 934 if (user_len > 65536) 935 user_len = 65536; 936 buffer = dasd_get_user_string(user_buf, user_len); 937 if (IS_ERR(buffer)) 938 return PTR_ERR(buffer); 939 940 str = skip_spaces(buffer); 941 rc = user_len; 942 if (strncmp(str, "reset", 5) == 0) { 943 dasd_profile_reset(prof); 944 } else if (strncmp(str, "on", 2) == 0) { 945 rc = dasd_profile_on(prof); 946 if (!rc) 947 rc = user_len; 948 } else if (strncmp(str, "off", 3) == 0) { 949 dasd_profile_off(prof); 950 } else 951 rc = -EINVAL; 952 vfree(buffer); 953 return rc; 954 } 955 956 static void dasd_stats_array(struct seq_file *m, unsigned int *array) 957 { 958 int i; 959 960 for (i = 0; i < 32; i++) 961 seq_printf(m, "%u ", array[i]); 962 seq_putc(m, '\n'); 963 } 964 965 static void dasd_stats_seq_print(struct seq_file *m, 966 struct dasd_profile_info *data) 967 { 968 seq_printf(m, "start_time %ld.%09ld\n", 969 data->starttod.tv_sec, data->starttod.tv_nsec); 970 seq_printf(m, "total_requests %u\n", data->dasd_io_reqs); 971 seq_printf(m, "total_sectors %u\n", data->dasd_io_sects); 972 seq_printf(m, "total_pav %u\n", data->dasd_io_alias); 973 seq_printf(m, "total_hpf %u\n", data->dasd_io_tpm); 974 seq_printf(m, "histogram_sectors "); 975 dasd_stats_array(m, data->dasd_io_secs); 976 seq_printf(m, "histogram_io_times "); 977 dasd_stats_array(m, data->dasd_io_times); 978 seq_printf(m, "histogram_io_times_weighted "); 979 dasd_stats_array(m, data->dasd_io_timps); 980 seq_printf(m, "histogram_time_build_to_ssch "); 981 dasd_stats_array(m, data->dasd_io_time1); 982 seq_printf(m, "histogram_time_ssch_to_irq "); 983 dasd_stats_array(m, data->dasd_io_time2); 984 seq_printf(m, "histogram_time_ssch_to_irq_weighted "); 985 dasd_stats_array(m, data->dasd_io_time2ps); 986 seq_printf(m, "histogram_time_irq_to_end "); 987 dasd_stats_array(m, data->dasd_io_time3); 988 seq_printf(m, "histogram_ccw_queue_length "); 989 dasd_stats_array(m, data->dasd_io_nr_req); 990 seq_printf(m, "total_read_requests %u\n", data->dasd_read_reqs); 991 seq_printf(m, "total_read_sectors %u\n", data->dasd_read_sects); 992 seq_printf(m, "total_read_pav %u\n", data->dasd_read_alias); 993 seq_printf(m, "total_read_hpf %u\n", data->dasd_read_tpm); 994 seq_printf(m, "histogram_read_sectors "); 995 dasd_stats_array(m, data->dasd_read_secs); 996 seq_printf(m, "histogram_read_times "); 997 dasd_stats_array(m, data->dasd_read_times); 998 seq_printf(m, "histogram_read_time_build_to_ssch "); 999 dasd_stats_array(m, data->dasd_read_time1); 1000 seq_printf(m, "histogram_read_time_ssch_to_irq "); 1001 dasd_stats_array(m, data->dasd_read_time2); 1002 seq_printf(m, "histogram_read_time_irq_to_end "); 1003 dasd_stats_array(m, data->dasd_read_time3); 1004 seq_printf(m, "histogram_read_ccw_queue_length "); 1005 dasd_stats_array(m, data->dasd_read_nr_req); 1006 } 1007 1008 static int dasd_stats_show(struct seq_file *m, void *v) 1009 { 1010 struct dasd_profile *profile; 1011 struct dasd_profile_info *data; 1012 1013 profile = m->private; 1014 spin_lock_bh(&profile->lock); 1015 data = profile->data; 1016 if (!data) { 1017 spin_unlock_bh(&profile->lock); 1018 seq_printf(m, "disabled\n"); 1019 return 0; 1020 } 1021 dasd_stats_seq_print(m, data); 1022 spin_unlock_bh(&profile->lock); 1023 return 0; 1024 } 1025 1026 static int dasd_stats_open(struct inode *inode, struct file *file) 1027 { 1028 struct dasd_profile *profile = inode->i_private; 1029 return single_open(file, dasd_stats_show, profile); 1030 } 1031 1032 static const struct file_operations dasd_stats_raw_fops = { 1033 .owner = THIS_MODULE, 1034 .open = dasd_stats_open, 1035 .read = seq_read, 1036 .llseek = seq_lseek, 1037 .release = single_release, 1038 .write = dasd_stats_write, 1039 }; 1040 1041 static ssize_t dasd_stats_global_write(struct file *file, 1042 const char __user *user_buf, 1043 size_t user_len, loff_t *pos) 1044 { 1045 char *buffer, *str; 1046 ssize_t rc; 1047 1048 if (user_len > 65536) 1049 user_len = 65536; 1050 buffer = dasd_get_user_string(user_buf, user_len); 1051 if (IS_ERR(buffer)) 1052 return PTR_ERR(buffer); 1053 str = skip_spaces(buffer); 1054 rc = user_len; 1055 if (strncmp(str, "reset", 5) == 0) { 1056 dasd_global_profile_reset(); 1057 } else if (strncmp(str, "on", 2) == 0) { 1058 dasd_global_profile_reset(); 1059 dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY; 1060 } else if (strncmp(str, "off", 3) == 0) { 1061 dasd_global_profile_level = DASD_PROFILE_OFF; 1062 } else 1063 rc = -EINVAL; 1064 vfree(buffer); 1065 return rc; 1066 } 1067 1068 static int dasd_stats_global_show(struct seq_file *m, void *v) 1069 { 1070 if (!dasd_global_profile_level) { 1071 seq_printf(m, "disabled\n"); 1072 return 0; 1073 } 1074 dasd_stats_seq_print(m, &dasd_global_profile_data); 1075 return 0; 1076 } 1077 1078 static int dasd_stats_global_open(struct inode *inode, struct file *file) 1079 { 1080 return single_open(file, dasd_stats_global_show, NULL); 1081 } 1082 1083 static const struct file_operations dasd_stats_global_fops = { 1084 .owner = THIS_MODULE, 1085 .open = dasd_stats_global_open, 1086 .read = seq_read, 1087 .llseek = seq_lseek, 1088 .release = single_release, 1089 .write = dasd_stats_global_write, 1090 }; 1091 1092 static void dasd_profile_init(struct dasd_profile *profile, 1093 struct dentry *base_dentry) 1094 { 1095 umode_t mode; 1096 struct dentry *pde; 1097 1098 if (!base_dentry) 1099 return; 1100 profile->dentry = NULL; 1101 profile->data = NULL; 1102 mode = (S_IRUSR | S_IWUSR | S_IFREG); 1103 pde = debugfs_create_file("statistics", mode, base_dentry, 1104 profile, &dasd_stats_raw_fops); 1105 if (pde && !IS_ERR(pde)) 1106 profile->dentry = pde; 1107 return; 1108 } 1109 1110 static void dasd_profile_exit(struct dasd_profile *profile) 1111 { 1112 dasd_profile_off(profile); 1113 if (profile->dentry) { 1114 debugfs_remove(profile->dentry); 1115 profile->dentry = NULL; 1116 } 1117 } 1118 1119 static void dasd_statistics_removeroot(void) 1120 { 1121 dasd_global_profile_level = DASD_PROFILE_OFF; 1122 if (dasd_global_profile_dentry) { 1123 debugfs_remove(dasd_global_profile_dentry); 1124 dasd_global_profile_dentry = NULL; 1125 } 1126 if (dasd_debugfs_global_entry) 1127 debugfs_remove(dasd_debugfs_global_entry); 1128 if (dasd_debugfs_root_entry) 1129 debugfs_remove(dasd_debugfs_root_entry); 1130 } 1131 1132 static void dasd_statistics_createroot(void) 1133 { 1134 umode_t mode; 1135 struct dentry *pde; 1136 1137 dasd_debugfs_root_entry = NULL; 1138 dasd_debugfs_global_entry = NULL; 1139 dasd_global_profile_dentry = NULL; 1140 pde = debugfs_create_dir("dasd", NULL); 1141 if (!pde || IS_ERR(pde)) 1142 goto error; 1143 dasd_debugfs_root_entry = pde; 1144 pde = debugfs_create_dir("global", dasd_debugfs_root_entry); 1145 if (!pde || IS_ERR(pde)) 1146 goto error; 1147 dasd_debugfs_global_entry = pde; 1148 1149 mode = (S_IRUSR | S_IWUSR | S_IFREG); 1150 pde = debugfs_create_file("statistics", mode, dasd_debugfs_global_entry, 1151 NULL, &dasd_stats_global_fops); 1152 if (!pde || IS_ERR(pde)) 1153 goto error; 1154 dasd_global_profile_dentry = pde; 1155 return; 1156 1157 error: 1158 DBF_EVENT(DBF_ERR, "%s", 1159 "Creation of the dasd debugfs interface failed"); 1160 dasd_statistics_removeroot(); 1161 return; 1162 } 1163 1164 #else 1165 #define dasd_profile_start(block, cqr, req) do {} while (0) 1166 #define dasd_profile_end(block, cqr, req) do {} while (0) 1167 1168 static void dasd_statistics_createroot(void) 1169 { 1170 return; 1171 } 1172 1173 static void dasd_statistics_removeroot(void) 1174 { 1175 return; 1176 } 1177 1178 int dasd_stats_generic_show(struct seq_file *m, void *v) 1179 { 1180 seq_printf(m, "Statistics are not activated in this kernel\n"); 1181 return 0; 1182 } 1183 1184 static void dasd_profile_init(struct dasd_profile *profile, 1185 struct dentry *base_dentry) 1186 { 1187 return; 1188 } 1189 1190 static void dasd_profile_exit(struct dasd_profile *profile) 1191 { 1192 return; 1193 } 1194 1195 int dasd_profile_on(struct dasd_profile *profile) 1196 { 1197 return 0; 1198 } 1199 1200 #endif /* CONFIG_DASD_PROFILE */ 1201 1202 /* 1203 * Allocate memory for a channel program with 'cplength' channel 1204 * command words and 'datasize' additional space. There are two 1205 * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed 1206 * memory and 2) dasd_smalloc_request uses the static ccw memory 1207 * that gets allocated for each device. 1208 */ 1209 struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength, 1210 int datasize, 1211 struct dasd_device *device) 1212 { 1213 struct dasd_ccw_req *cqr; 1214 1215 /* Sanity checks */ 1216 BUG_ON(datasize > PAGE_SIZE || 1217 (cplength*sizeof(struct ccw1)) > PAGE_SIZE); 1218 1219 cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC); 1220 if (cqr == NULL) 1221 return ERR_PTR(-ENOMEM); 1222 cqr->cpaddr = NULL; 1223 if (cplength > 0) { 1224 cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1), 1225 GFP_ATOMIC | GFP_DMA); 1226 if (cqr->cpaddr == NULL) { 1227 kfree(cqr); 1228 return ERR_PTR(-ENOMEM); 1229 } 1230 } 1231 cqr->data = NULL; 1232 if (datasize > 0) { 1233 cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA); 1234 if (cqr->data == NULL) { 1235 kfree(cqr->cpaddr); 1236 kfree(cqr); 1237 return ERR_PTR(-ENOMEM); 1238 } 1239 } 1240 cqr->magic = magic; 1241 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); 1242 dasd_get_device(device); 1243 return cqr; 1244 } 1245 1246 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength, 1247 int datasize, 1248 struct dasd_device *device) 1249 { 1250 unsigned long flags; 1251 struct dasd_ccw_req *cqr; 1252 char *data; 1253 int size; 1254 1255 size = (sizeof(struct dasd_ccw_req) + 7L) & -8L; 1256 if (cplength > 0) 1257 size += cplength * sizeof(struct ccw1); 1258 if (datasize > 0) 1259 size += datasize; 1260 spin_lock_irqsave(&device->mem_lock, flags); 1261 cqr = (struct dasd_ccw_req *) 1262 dasd_alloc_chunk(&device->ccw_chunks, size); 1263 spin_unlock_irqrestore(&device->mem_lock, flags); 1264 if (cqr == NULL) 1265 return ERR_PTR(-ENOMEM); 1266 memset(cqr, 0, sizeof(struct dasd_ccw_req)); 1267 data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L); 1268 cqr->cpaddr = NULL; 1269 if (cplength > 0) { 1270 cqr->cpaddr = (struct ccw1 *) data; 1271 data += cplength*sizeof(struct ccw1); 1272 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1)); 1273 } 1274 cqr->data = NULL; 1275 if (datasize > 0) { 1276 cqr->data = data; 1277 memset(cqr->data, 0, datasize); 1278 } 1279 cqr->magic = magic; 1280 set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags); 1281 dasd_get_device(device); 1282 return cqr; 1283 } 1284 1285 /* 1286 * Free memory of a channel program. This function needs to free all the 1287 * idal lists that might have been created by dasd_set_cda and the 1288 * struct dasd_ccw_req itself. 1289 */ 1290 void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device) 1291 { 1292 #ifdef CONFIG_64BIT 1293 struct ccw1 *ccw; 1294 1295 /* Clear any idals used for the request. */ 1296 ccw = cqr->cpaddr; 1297 do { 1298 clear_normalized_cda(ccw); 1299 } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC)); 1300 #endif 1301 kfree(cqr->cpaddr); 1302 kfree(cqr->data); 1303 kfree(cqr); 1304 dasd_put_device(device); 1305 } 1306 1307 void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device) 1308 { 1309 unsigned long flags; 1310 1311 spin_lock_irqsave(&device->mem_lock, flags); 1312 dasd_free_chunk(&device->ccw_chunks, cqr); 1313 spin_unlock_irqrestore(&device->mem_lock, flags); 1314 dasd_put_device(device); 1315 } 1316 1317 /* 1318 * Check discipline magic in cqr. 1319 */ 1320 static inline int dasd_check_cqr(struct dasd_ccw_req *cqr) 1321 { 1322 struct dasd_device *device; 1323 1324 if (cqr == NULL) 1325 return -EINVAL; 1326 device = cqr->startdev; 1327 if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) { 1328 DBF_DEV_EVENT(DBF_WARNING, device, 1329 " dasd_ccw_req 0x%08x magic doesn't match" 1330 " discipline 0x%08x", 1331 cqr->magic, 1332 *(unsigned int *) device->discipline->name); 1333 return -EINVAL; 1334 } 1335 return 0; 1336 } 1337 1338 /* 1339 * Terminate the current i/o and set the request to clear_pending. 1340 * Timer keeps device runnig. 1341 * ccw_device_clear can fail if the i/o subsystem 1342 * is in a bad mood. 1343 */ 1344 int dasd_term_IO(struct dasd_ccw_req *cqr) 1345 { 1346 struct dasd_device *device; 1347 int retries, rc; 1348 char errorstring[ERRORLENGTH]; 1349 1350 /* Check the cqr */ 1351 rc = dasd_check_cqr(cqr); 1352 if (rc) 1353 return rc; 1354 retries = 0; 1355 device = (struct dasd_device *) cqr->startdev; 1356 while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) { 1357 rc = ccw_device_clear(device->cdev, (long) cqr); 1358 switch (rc) { 1359 case 0: /* termination successful */ 1360 cqr->status = DASD_CQR_CLEAR_PENDING; 1361 cqr->stopclk = get_tod_clock(); 1362 cqr->starttime = 0; 1363 DBF_DEV_EVENT(DBF_DEBUG, device, 1364 "terminate cqr %p successful", 1365 cqr); 1366 break; 1367 case -ENODEV: 1368 DBF_DEV_EVENT(DBF_ERR, device, "%s", 1369 "device gone, retry"); 1370 break; 1371 case -EIO: 1372 DBF_DEV_EVENT(DBF_ERR, device, "%s", 1373 "I/O error, retry"); 1374 break; 1375 case -EINVAL: 1376 case -EBUSY: 1377 DBF_DEV_EVENT(DBF_ERR, device, "%s", 1378 "device busy, retry later"); 1379 break; 1380 default: 1381 /* internal error 10 - unknown rc*/ 1382 snprintf(errorstring, ERRORLENGTH, "10 %d", rc); 1383 dev_err(&device->cdev->dev, "An error occurred in the " 1384 "DASD device driver, reason=%s\n", errorstring); 1385 BUG(); 1386 break; 1387 } 1388 retries++; 1389 } 1390 dasd_schedule_device_bh(device); 1391 return rc; 1392 } 1393 1394 /* 1395 * Start the i/o. This start_IO can fail if the channel is really busy. 1396 * In that case set up a timer to start the request later. 1397 */ 1398 int dasd_start_IO(struct dasd_ccw_req *cqr) 1399 { 1400 struct dasd_device *device; 1401 int rc; 1402 char errorstring[ERRORLENGTH]; 1403 1404 /* Check the cqr */ 1405 rc = dasd_check_cqr(cqr); 1406 if (rc) { 1407 cqr->intrc = rc; 1408 return rc; 1409 } 1410 device = (struct dasd_device *) cqr->startdev; 1411 if (((cqr->block && 1412 test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) || 1413 test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) && 1414 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { 1415 DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p " 1416 "because of stolen lock", cqr); 1417 cqr->status = DASD_CQR_ERROR; 1418 cqr->intrc = -EPERM; 1419 return -EPERM; 1420 } 1421 if (cqr->retries < 0) { 1422 /* internal error 14 - start_IO run out of retries */ 1423 sprintf(errorstring, "14 %p", cqr); 1424 dev_err(&device->cdev->dev, "An error occurred in the DASD " 1425 "device driver, reason=%s\n", errorstring); 1426 cqr->status = DASD_CQR_ERROR; 1427 return -EIO; 1428 } 1429 cqr->startclk = get_tod_clock(); 1430 cqr->starttime = jiffies; 1431 cqr->retries--; 1432 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) { 1433 cqr->lpm &= device->path_data.opm; 1434 if (!cqr->lpm) 1435 cqr->lpm = device->path_data.opm; 1436 } 1437 if (cqr->cpmode == 1) { 1438 rc = ccw_device_tm_start(device->cdev, cqr->cpaddr, 1439 (long) cqr, cqr->lpm); 1440 } else { 1441 rc = ccw_device_start(device->cdev, cqr->cpaddr, 1442 (long) cqr, cqr->lpm, 0); 1443 } 1444 switch (rc) { 1445 case 0: 1446 cqr->status = DASD_CQR_IN_IO; 1447 break; 1448 case -EBUSY: 1449 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1450 "start_IO: device busy, retry later"); 1451 break; 1452 case -ETIMEDOUT: 1453 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1454 "start_IO: request timeout, retry later"); 1455 break; 1456 case -EACCES: 1457 /* -EACCES indicates that the request used only a subset of the 1458 * available paths and all these paths are gone. If the lpm of 1459 * this request was only a subset of the opm (e.g. the ppm) then 1460 * we just do a retry with all available paths. 1461 * If we already use the full opm, something is amiss, and we 1462 * need a full path verification. 1463 */ 1464 if (test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) { 1465 DBF_DEV_EVENT(DBF_WARNING, device, 1466 "start_IO: selected paths gone (%x)", 1467 cqr->lpm); 1468 } else if (cqr->lpm != device->path_data.opm) { 1469 cqr->lpm = device->path_data.opm; 1470 DBF_DEV_EVENT(DBF_DEBUG, device, "%s", 1471 "start_IO: selected paths gone," 1472 " retry on all paths"); 1473 } else { 1474 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1475 "start_IO: all paths in opm gone," 1476 " do path verification"); 1477 dasd_generic_last_path_gone(device); 1478 device->path_data.opm = 0; 1479 device->path_data.ppm = 0; 1480 device->path_data.npm = 0; 1481 device->path_data.tbvpm = 1482 ccw_device_get_path_mask(device->cdev); 1483 } 1484 break; 1485 case -ENODEV: 1486 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1487 "start_IO: -ENODEV device gone, retry"); 1488 break; 1489 case -EIO: 1490 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1491 "start_IO: -EIO device gone, retry"); 1492 break; 1493 case -EINVAL: 1494 /* most likely caused in power management context */ 1495 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 1496 "start_IO: -EINVAL device currently " 1497 "not accessible"); 1498 break; 1499 default: 1500 /* internal error 11 - unknown rc */ 1501 snprintf(errorstring, ERRORLENGTH, "11 %d", rc); 1502 dev_err(&device->cdev->dev, 1503 "An error occurred in the DASD device driver, " 1504 "reason=%s\n", errorstring); 1505 BUG(); 1506 break; 1507 } 1508 cqr->intrc = rc; 1509 return rc; 1510 } 1511 1512 /* 1513 * Timeout function for dasd devices. This is used for different purposes 1514 * 1) missing interrupt handler for normal operation 1515 * 2) delayed start of request where start_IO failed with -EBUSY 1516 * 3) timeout for missing state change interrupts 1517 * The head of the ccw queue will have status DASD_CQR_IN_IO for 1), 1518 * DASD_CQR_QUEUED for 2) and 3). 1519 */ 1520 static void dasd_device_timeout(unsigned long ptr) 1521 { 1522 unsigned long flags; 1523 struct dasd_device *device; 1524 1525 device = (struct dasd_device *) ptr; 1526 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 1527 /* re-activate request queue */ 1528 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING); 1529 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 1530 dasd_schedule_device_bh(device); 1531 } 1532 1533 /* 1534 * Setup timeout for a device in jiffies. 1535 */ 1536 void dasd_device_set_timer(struct dasd_device *device, int expires) 1537 { 1538 if (expires == 0) 1539 del_timer(&device->timer); 1540 else 1541 mod_timer(&device->timer, jiffies + expires); 1542 } 1543 1544 /* 1545 * Clear timeout for a device. 1546 */ 1547 void dasd_device_clear_timer(struct dasd_device *device) 1548 { 1549 del_timer(&device->timer); 1550 } 1551 1552 static void dasd_handle_killed_request(struct ccw_device *cdev, 1553 unsigned long intparm) 1554 { 1555 struct dasd_ccw_req *cqr; 1556 struct dasd_device *device; 1557 1558 if (!intparm) 1559 return; 1560 cqr = (struct dasd_ccw_req *) intparm; 1561 if (cqr->status != DASD_CQR_IN_IO) { 1562 DBF_EVENT_DEVID(DBF_DEBUG, cdev, 1563 "invalid status in handle_killed_request: " 1564 "%02x", cqr->status); 1565 return; 1566 } 1567 1568 device = dasd_device_from_cdev_locked(cdev); 1569 if (IS_ERR(device)) { 1570 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s", 1571 "unable to get device from cdev"); 1572 return; 1573 } 1574 1575 if (!cqr->startdev || 1576 device != cqr->startdev || 1577 strncmp(cqr->startdev->discipline->ebcname, 1578 (char *) &cqr->magic, 4)) { 1579 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s", 1580 "invalid device in request"); 1581 dasd_put_device(device); 1582 return; 1583 } 1584 1585 /* Schedule request to be retried. */ 1586 cqr->status = DASD_CQR_QUEUED; 1587 1588 dasd_device_clear_timer(device); 1589 dasd_schedule_device_bh(device); 1590 dasd_put_device(device); 1591 } 1592 1593 void dasd_generic_handle_state_change(struct dasd_device *device) 1594 { 1595 /* First of all start sense subsystem status request. */ 1596 dasd_eer_snss(device); 1597 1598 dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING); 1599 dasd_schedule_device_bh(device); 1600 if (device->block) 1601 dasd_schedule_block_bh(device->block); 1602 } 1603 1604 /* 1605 * Interrupt handler for "normal" ssch-io based dasd devices. 1606 */ 1607 void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm, 1608 struct irb *irb) 1609 { 1610 struct dasd_ccw_req *cqr, *next; 1611 struct dasd_device *device; 1612 unsigned long long now; 1613 int expires; 1614 1615 if (IS_ERR(irb)) { 1616 switch (PTR_ERR(irb)) { 1617 case -EIO: 1618 break; 1619 case -ETIMEDOUT: 1620 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: " 1621 "request timed out\n", __func__); 1622 break; 1623 default: 1624 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: " 1625 "unknown error %ld\n", __func__, 1626 PTR_ERR(irb)); 1627 } 1628 dasd_handle_killed_request(cdev, intparm); 1629 return; 1630 } 1631 1632 now = get_tod_clock(); 1633 cqr = (struct dasd_ccw_req *) intparm; 1634 /* check for conditions that should be handled immediately */ 1635 if (!cqr || 1636 !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) && 1637 scsw_cstat(&irb->scsw) == 0)) { 1638 if (cqr) 1639 memcpy(&cqr->irb, irb, sizeof(*irb)); 1640 device = dasd_device_from_cdev_locked(cdev); 1641 if (IS_ERR(device)) 1642 return; 1643 /* ignore unsolicited interrupts for DIAG discipline */ 1644 if (device->discipline == dasd_diag_discipline_pointer) { 1645 dasd_put_device(device); 1646 return; 1647 } 1648 device->discipline->dump_sense_dbf(device, irb, "int"); 1649 if (device->features & DASD_FEATURE_ERPLOG) 1650 device->discipline->dump_sense(device, cqr, irb); 1651 device->discipline->check_for_device_change(device, cqr, irb); 1652 dasd_put_device(device); 1653 } 1654 if (!cqr) 1655 return; 1656 1657 device = (struct dasd_device *) cqr->startdev; 1658 if (!device || 1659 strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) { 1660 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s", 1661 "invalid device in request"); 1662 return; 1663 } 1664 1665 /* Check for clear pending */ 1666 if (cqr->status == DASD_CQR_CLEAR_PENDING && 1667 scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) { 1668 cqr->status = DASD_CQR_CLEARED; 1669 dasd_device_clear_timer(device); 1670 wake_up(&dasd_flush_wq); 1671 dasd_schedule_device_bh(device); 1672 return; 1673 } 1674 1675 /* check status - the request might have been killed by dyn detach */ 1676 if (cqr->status != DASD_CQR_IN_IO) { 1677 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, " 1678 "status %02x", dev_name(&cdev->dev), cqr->status); 1679 return; 1680 } 1681 1682 next = NULL; 1683 expires = 0; 1684 if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) && 1685 scsw_cstat(&irb->scsw) == 0) { 1686 /* request was completed successfully */ 1687 cqr->status = DASD_CQR_SUCCESS; 1688 cqr->stopclk = now; 1689 /* Start first request on queue if possible -> fast_io. */ 1690 if (cqr->devlist.next != &device->ccw_queue) { 1691 next = list_entry(cqr->devlist.next, 1692 struct dasd_ccw_req, devlist); 1693 } 1694 } else { /* error */ 1695 /* 1696 * If we don't want complex ERP for this request, then just 1697 * reset this and retry it in the fastpath 1698 */ 1699 if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) && 1700 cqr->retries > 0) { 1701 if (cqr->lpm == device->path_data.opm) 1702 DBF_DEV_EVENT(DBF_DEBUG, device, 1703 "default ERP in fastpath " 1704 "(%i retries left)", 1705 cqr->retries); 1706 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) 1707 cqr->lpm = device->path_data.opm; 1708 cqr->status = DASD_CQR_QUEUED; 1709 next = cqr; 1710 } else 1711 cqr->status = DASD_CQR_ERROR; 1712 } 1713 if (next && (next->status == DASD_CQR_QUEUED) && 1714 (!device->stopped)) { 1715 if (device->discipline->start_IO(next) == 0) 1716 expires = next->expires; 1717 } 1718 if (expires != 0) 1719 dasd_device_set_timer(device, expires); 1720 else 1721 dasd_device_clear_timer(device); 1722 dasd_schedule_device_bh(device); 1723 } 1724 1725 enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb) 1726 { 1727 struct dasd_device *device; 1728 1729 device = dasd_device_from_cdev_locked(cdev); 1730 1731 if (IS_ERR(device)) 1732 goto out; 1733 if (test_bit(DASD_FLAG_OFFLINE, &device->flags) || 1734 device->state != device->target || 1735 !device->discipline->check_for_device_change){ 1736 dasd_put_device(device); 1737 goto out; 1738 } 1739 if (device->discipline->dump_sense_dbf) 1740 device->discipline->dump_sense_dbf(device, irb, "uc"); 1741 device->discipline->check_for_device_change(device, NULL, irb); 1742 dasd_put_device(device); 1743 out: 1744 return UC_TODO_RETRY; 1745 } 1746 EXPORT_SYMBOL_GPL(dasd_generic_uc_handler); 1747 1748 /* 1749 * If we have an error on a dasd_block layer request then we cancel 1750 * and return all further requests from the same dasd_block as well. 1751 */ 1752 static void __dasd_device_recovery(struct dasd_device *device, 1753 struct dasd_ccw_req *ref_cqr) 1754 { 1755 struct list_head *l, *n; 1756 struct dasd_ccw_req *cqr; 1757 1758 /* 1759 * only requeue request that came from the dasd_block layer 1760 */ 1761 if (!ref_cqr->block) 1762 return; 1763 1764 list_for_each_safe(l, n, &device->ccw_queue) { 1765 cqr = list_entry(l, struct dasd_ccw_req, devlist); 1766 if (cqr->status == DASD_CQR_QUEUED && 1767 ref_cqr->block == cqr->block) { 1768 cqr->status = DASD_CQR_CLEARED; 1769 } 1770 } 1771 }; 1772 1773 /* 1774 * Remove those ccw requests from the queue that need to be returned 1775 * to the upper layer. 1776 */ 1777 static void __dasd_device_process_ccw_queue(struct dasd_device *device, 1778 struct list_head *final_queue) 1779 { 1780 struct list_head *l, *n; 1781 struct dasd_ccw_req *cqr; 1782 1783 /* Process request with final status. */ 1784 list_for_each_safe(l, n, &device->ccw_queue) { 1785 cqr = list_entry(l, struct dasd_ccw_req, devlist); 1786 1787 /* Skip any non-final request. */ 1788 if (cqr->status == DASD_CQR_QUEUED || 1789 cqr->status == DASD_CQR_IN_IO || 1790 cqr->status == DASD_CQR_CLEAR_PENDING) 1791 continue; 1792 if (cqr->status == DASD_CQR_ERROR) { 1793 __dasd_device_recovery(device, cqr); 1794 } 1795 /* Rechain finished requests to final queue */ 1796 list_move_tail(&cqr->devlist, final_queue); 1797 } 1798 } 1799 1800 /* 1801 * the cqrs from the final queue are returned to the upper layer 1802 * by setting a dasd_block state and calling the callback function 1803 */ 1804 static void __dasd_device_process_final_queue(struct dasd_device *device, 1805 struct list_head *final_queue) 1806 { 1807 struct list_head *l, *n; 1808 struct dasd_ccw_req *cqr; 1809 struct dasd_block *block; 1810 void (*callback)(struct dasd_ccw_req *, void *data); 1811 void *callback_data; 1812 char errorstring[ERRORLENGTH]; 1813 1814 list_for_each_safe(l, n, final_queue) { 1815 cqr = list_entry(l, struct dasd_ccw_req, devlist); 1816 list_del_init(&cqr->devlist); 1817 block = cqr->block; 1818 callback = cqr->callback; 1819 callback_data = cqr->callback_data; 1820 if (block) 1821 spin_lock_bh(&block->queue_lock); 1822 switch (cqr->status) { 1823 case DASD_CQR_SUCCESS: 1824 cqr->status = DASD_CQR_DONE; 1825 break; 1826 case DASD_CQR_ERROR: 1827 cqr->status = DASD_CQR_NEED_ERP; 1828 break; 1829 case DASD_CQR_CLEARED: 1830 cqr->status = DASD_CQR_TERMINATED; 1831 break; 1832 default: 1833 /* internal error 12 - wrong cqr status*/ 1834 snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status); 1835 dev_err(&device->cdev->dev, 1836 "An error occurred in the DASD device driver, " 1837 "reason=%s\n", errorstring); 1838 BUG(); 1839 } 1840 if (cqr->callback != NULL) 1841 (callback)(cqr, callback_data); 1842 if (block) 1843 spin_unlock_bh(&block->queue_lock); 1844 } 1845 } 1846 1847 /* 1848 * Take a look at the first request on the ccw queue and check 1849 * if it reached its expire time. If so, terminate the IO. 1850 */ 1851 static void __dasd_device_check_expire(struct dasd_device *device) 1852 { 1853 struct dasd_ccw_req *cqr; 1854 1855 if (list_empty(&device->ccw_queue)) 1856 return; 1857 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist); 1858 if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) && 1859 (time_after_eq(jiffies, cqr->expires + cqr->starttime))) { 1860 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) { 1861 /* 1862 * IO in safe offline processing should not 1863 * run out of retries 1864 */ 1865 cqr->retries++; 1866 } 1867 if (device->discipline->term_IO(cqr) != 0) { 1868 /* Hmpf, try again in 5 sec */ 1869 dev_err(&device->cdev->dev, 1870 "cqr %p timed out (%lus) but cannot be " 1871 "ended, retrying in 5 s\n", 1872 cqr, (cqr->expires/HZ)); 1873 cqr->expires += 5*HZ; 1874 dasd_device_set_timer(device, 5*HZ); 1875 } else { 1876 dev_err(&device->cdev->dev, 1877 "cqr %p timed out (%lus), %i retries " 1878 "remaining\n", cqr, (cqr->expires/HZ), 1879 cqr->retries); 1880 } 1881 } 1882 } 1883 1884 /* 1885 * Take a look at the first request on the ccw queue and check 1886 * if it needs to be started. 1887 */ 1888 static void __dasd_device_start_head(struct dasd_device *device) 1889 { 1890 struct dasd_ccw_req *cqr; 1891 int rc; 1892 1893 if (list_empty(&device->ccw_queue)) 1894 return; 1895 cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist); 1896 if (cqr->status != DASD_CQR_QUEUED) 1897 return; 1898 /* when device is stopped, return request to previous layer 1899 * exception: only the disconnect or unresumed bits are set and the 1900 * cqr is a path verification request 1901 */ 1902 if (device->stopped && 1903 !(!(device->stopped & ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM)) 1904 && test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))) { 1905 cqr->intrc = -EAGAIN; 1906 cqr->status = DASD_CQR_CLEARED; 1907 dasd_schedule_device_bh(device); 1908 return; 1909 } 1910 1911 rc = device->discipline->start_IO(cqr); 1912 if (rc == 0) 1913 dasd_device_set_timer(device, cqr->expires); 1914 else if (rc == -EACCES) { 1915 dasd_schedule_device_bh(device); 1916 } else 1917 /* Hmpf, try again in 1/2 sec */ 1918 dasd_device_set_timer(device, 50); 1919 } 1920 1921 static void __dasd_device_check_path_events(struct dasd_device *device) 1922 { 1923 int rc; 1924 1925 if (device->path_data.tbvpm) { 1926 if (device->stopped & ~(DASD_STOPPED_DC_WAIT | 1927 DASD_UNRESUMED_PM)) 1928 return; 1929 rc = device->discipline->verify_path( 1930 device, device->path_data.tbvpm); 1931 if (rc) 1932 dasd_device_set_timer(device, 50); 1933 else 1934 device->path_data.tbvpm = 0; 1935 } 1936 }; 1937 1938 /* 1939 * Go through all request on the dasd_device request queue, 1940 * terminate them on the cdev if necessary, and return them to the 1941 * submitting layer via callback. 1942 * Note: 1943 * Make sure that all 'submitting layers' still exist when 1944 * this function is called!. In other words, when 'device' is a base 1945 * device then all block layer requests must have been removed before 1946 * via dasd_flush_block_queue. 1947 */ 1948 int dasd_flush_device_queue(struct dasd_device *device) 1949 { 1950 struct dasd_ccw_req *cqr, *n; 1951 int rc; 1952 struct list_head flush_queue; 1953 1954 INIT_LIST_HEAD(&flush_queue); 1955 spin_lock_irq(get_ccwdev_lock(device->cdev)); 1956 rc = 0; 1957 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) { 1958 /* Check status and move request to flush_queue */ 1959 switch (cqr->status) { 1960 case DASD_CQR_IN_IO: 1961 rc = device->discipline->term_IO(cqr); 1962 if (rc) { 1963 /* unable to terminate requeust */ 1964 dev_err(&device->cdev->dev, 1965 "Flushing the DASD request queue " 1966 "failed for request %p\n", cqr); 1967 /* stop flush processing */ 1968 goto finished; 1969 } 1970 break; 1971 case DASD_CQR_QUEUED: 1972 cqr->stopclk = get_tod_clock(); 1973 cqr->status = DASD_CQR_CLEARED; 1974 break; 1975 default: /* no need to modify the others */ 1976 break; 1977 } 1978 list_move_tail(&cqr->devlist, &flush_queue); 1979 } 1980 finished: 1981 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 1982 /* 1983 * After this point all requests must be in state CLEAR_PENDING, 1984 * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become 1985 * one of the others. 1986 */ 1987 list_for_each_entry_safe(cqr, n, &flush_queue, devlist) 1988 wait_event(dasd_flush_wq, 1989 (cqr->status != DASD_CQR_CLEAR_PENDING)); 1990 /* 1991 * Now set each request back to TERMINATED, DONE or NEED_ERP 1992 * and call the callback function of flushed requests 1993 */ 1994 __dasd_device_process_final_queue(device, &flush_queue); 1995 return rc; 1996 } 1997 1998 /* 1999 * Acquire the device lock and process queues for the device. 2000 */ 2001 static void dasd_device_tasklet(struct dasd_device *device) 2002 { 2003 struct list_head final_queue; 2004 2005 atomic_set (&device->tasklet_scheduled, 0); 2006 INIT_LIST_HEAD(&final_queue); 2007 spin_lock_irq(get_ccwdev_lock(device->cdev)); 2008 /* Check expire time of first request on the ccw queue. */ 2009 __dasd_device_check_expire(device); 2010 /* find final requests on ccw queue */ 2011 __dasd_device_process_ccw_queue(device, &final_queue); 2012 __dasd_device_check_path_events(device); 2013 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 2014 /* Now call the callback function of requests with final status */ 2015 __dasd_device_process_final_queue(device, &final_queue); 2016 spin_lock_irq(get_ccwdev_lock(device->cdev)); 2017 /* Now check if the head of the ccw queue needs to be started. */ 2018 __dasd_device_start_head(device); 2019 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 2020 if (waitqueue_active(&shutdown_waitq)) 2021 wake_up(&shutdown_waitq); 2022 dasd_put_device(device); 2023 } 2024 2025 /* 2026 * Schedules a call to dasd_tasklet over the device tasklet. 2027 */ 2028 void dasd_schedule_device_bh(struct dasd_device *device) 2029 { 2030 /* Protect against rescheduling. */ 2031 if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0) 2032 return; 2033 dasd_get_device(device); 2034 tasklet_hi_schedule(&device->tasklet); 2035 } 2036 2037 void dasd_device_set_stop_bits(struct dasd_device *device, int bits) 2038 { 2039 device->stopped |= bits; 2040 } 2041 EXPORT_SYMBOL_GPL(dasd_device_set_stop_bits); 2042 2043 void dasd_device_remove_stop_bits(struct dasd_device *device, int bits) 2044 { 2045 device->stopped &= ~bits; 2046 if (!device->stopped) 2047 wake_up(&generic_waitq); 2048 } 2049 EXPORT_SYMBOL_GPL(dasd_device_remove_stop_bits); 2050 2051 /* 2052 * Queue a request to the head of the device ccw_queue. 2053 * Start the I/O if possible. 2054 */ 2055 void dasd_add_request_head(struct dasd_ccw_req *cqr) 2056 { 2057 struct dasd_device *device; 2058 unsigned long flags; 2059 2060 device = cqr->startdev; 2061 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 2062 cqr->status = DASD_CQR_QUEUED; 2063 list_add(&cqr->devlist, &device->ccw_queue); 2064 /* let the bh start the request to keep them in order */ 2065 dasd_schedule_device_bh(device); 2066 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 2067 } 2068 2069 /* 2070 * Queue a request to the tail of the device ccw_queue. 2071 * Start the I/O if possible. 2072 */ 2073 void dasd_add_request_tail(struct dasd_ccw_req *cqr) 2074 { 2075 struct dasd_device *device; 2076 unsigned long flags; 2077 2078 device = cqr->startdev; 2079 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 2080 cqr->status = DASD_CQR_QUEUED; 2081 list_add_tail(&cqr->devlist, &device->ccw_queue); 2082 /* let the bh start the request to keep them in order */ 2083 dasd_schedule_device_bh(device); 2084 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 2085 } 2086 2087 /* 2088 * Wakeup helper for the 'sleep_on' functions. 2089 */ 2090 void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data) 2091 { 2092 spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev)); 2093 cqr->callback_data = DASD_SLEEPON_END_TAG; 2094 spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev)); 2095 wake_up(&generic_waitq); 2096 } 2097 EXPORT_SYMBOL_GPL(dasd_wakeup_cb); 2098 2099 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr) 2100 { 2101 struct dasd_device *device; 2102 int rc; 2103 2104 device = cqr->startdev; 2105 spin_lock_irq(get_ccwdev_lock(device->cdev)); 2106 rc = (cqr->callback_data == DASD_SLEEPON_END_TAG); 2107 spin_unlock_irq(get_ccwdev_lock(device->cdev)); 2108 return rc; 2109 } 2110 2111 /* 2112 * checks if error recovery is necessary, returns 1 if yes, 0 otherwise. 2113 */ 2114 static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr) 2115 { 2116 struct dasd_device *device; 2117 dasd_erp_fn_t erp_fn; 2118 2119 if (cqr->status == DASD_CQR_FILLED) 2120 return 0; 2121 device = cqr->startdev; 2122 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) { 2123 if (cqr->status == DASD_CQR_TERMINATED) { 2124 device->discipline->handle_terminated_request(cqr); 2125 return 1; 2126 } 2127 if (cqr->status == DASD_CQR_NEED_ERP) { 2128 erp_fn = device->discipline->erp_action(cqr); 2129 erp_fn(cqr); 2130 return 1; 2131 } 2132 if (cqr->status == DASD_CQR_FAILED) 2133 dasd_log_sense(cqr, &cqr->irb); 2134 if (cqr->refers) { 2135 __dasd_process_erp(device, cqr); 2136 return 1; 2137 } 2138 } 2139 return 0; 2140 } 2141 2142 static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr) 2143 { 2144 if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) { 2145 if (cqr->refers) /* erp is not done yet */ 2146 return 1; 2147 return ((cqr->status != DASD_CQR_DONE) && 2148 (cqr->status != DASD_CQR_FAILED)); 2149 } else 2150 return (cqr->status == DASD_CQR_FILLED); 2151 } 2152 2153 static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible) 2154 { 2155 struct dasd_device *device; 2156 int rc; 2157 struct list_head ccw_queue; 2158 struct dasd_ccw_req *cqr; 2159 2160 INIT_LIST_HEAD(&ccw_queue); 2161 maincqr->status = DASD_CQR_FILLED; 2162 device = maincqr->startdev; 2163 list_add(&maincqr->blocklist, &ccw_queue); 2164 for (cqr = maincqr; __dasd_sleep_on_loop_condition(cqr); 2165 cqr = list_first_entry(&ccw_queue, 2166 struct dasd_ccw_req, blocklist)) { 2167 2168 if (__dasd_sleep_on_erp(cqr)) 2169 continue; 2170 if (cqr->status != DASD_CQR_FILLED) /* could be failed */ 2171 continue; 2172 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) && 2173 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { 2174 cqr->status = DASD_CQR_FAILED; 2175 cqr->intrc = -EPERM; 2176 continue; 2177 } 2178 /* Non-temporary stop condition will trigger fail fast */ 2179 if (device->stopped & ~DASD_STOPPED_PENDING && 2180 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) && 2181 (!dasd_eer_enabled(device))) { 2182 cqr->status = DASD_CQR_FAILED; 2183 cqr->intrc = -ENOLINK; 2184 continue; 2185 } 2186 /* Don't try to start requests if device is stopped */ 2187 if (interruptible) { 2188 rc = wait_event_interruptible( 2189 generic_waitq, !(device->stopped)); 2190 if (rc == -ERESTARTSYS) { 2191 cqr->status = DASD_CQR_FAILED; 2192 maincqr->intrc = rc; 2193 continue; 2194 } 2195 } else 2196 wait_event(generic_waitq, !(device->stopped)); 2197 2198 if (!cqr->callback) 2199 cqr->callback = dasd_wakeup_cb; 2200 2201 cqr->callback_data = DASD_SLEEPON_START_TAG; 2202 dasd_add_request_tail(cqr); 2203 if (interruptible) { 2204 rc = wait_event_interruptible( 2205 generic_waitq, _wait_for_wakeup(cqr)); 2206 if (rc == -ERESTARTSYS) { 2207 dasd_cancel_req(cqr); 2208 /* wait (non-interruptible) for final status */ 2209 wait_event(generic_waitq, 2210 _wait_for_wakeup(cqr)); 2211 cqr->status = DASD_CQR_FAILED; 2212 maincqr->intrc = rc; 2213 continue; 2214 } 2215 } else 2216 wait_event(generic_waitq, _wait_for_wakeup(cqr)); 2217 } 2218 2219 maincqr->endclk = get_tod_clock(); 2220 if ((maincqr->status != DASD_CQR_DONE) && 2221 (maincqr->intrc != -ERESTARTSYS)) 2222 dasd_log_sense(maincqr, &maincqr->irb); 2223 if (maincqr->status == DASD_CQR_DONE) 2224 rc = 0; 2225 else if (maincqr->intrc) 2226 rc = maincqr->intrc; 2227 else 2228 rc = -EIO; 2229 return rc; 2230 } 2231 2232 static inline int _wait_for_wakeup_queue(struct list_head *ccw_queue) 2233 { 2234 struct dasd_ccw_req *cqr; 2235 2236 list_for_each_entry(cqr, ccw_queue, blocklist) { 2237 if (cqr->callback_data != DASD_SLEEPON_END_TAG) 2238 return 0; 2239 } 2240 2241 return 1; 2242 } 2243 2244 static int _dasd_sleep_on_queue(struct list_head *ccw_queue, int interruptible) 2245 { 2246 struct dasd_device *device; 2247 int rc; 2248 struct dasd_ccw_req *cqr, *n; 2249 2250 retry: 2251 list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) { 2252 device = cqr->startdev; 2253 if (cqr->status != DASD_CQR_FILLED) /*could be failed*/ 2254 continue; 2255 2256 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) && 2257 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { 2258 cqr->status = DASD_CQR_FAILED; 2259 cqr->intrc = -EPERM; 2260 continue; 2261 } 2262 /*Non-temporary stop condition will trigger fail fast*/ 2263 if (device->stopped & ~DASD_STOPPED_PENDING && 2264 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) && 2265 !dasd_eer_enabled(device)) { 2266 cqr->status = DASD_CQR_FAILED; 2267 cqr->intrc = -EAGAIN; 2268 continue; 2269 } 2270 2271 /*Don't try to start requests if device is stopped*/ 2272 if (interruptible) { 2273 rc = wait_event_interruptible( 2274 generic_waitq, !device->stopped); 2275 if (rc == -ERESTARTSYS) { 2276 cqr->status = DASD_CQR_FAILED; 2277 cqr->intrc = rc; 2278 continue; 2279 } 2280 } else 2281 wait_event(generic_waitq, !(device->stopped)); 2282 2283 if (!cqr->callback) 2284 cqr->callback = dasd_wakeup_cb; 2285 cqr->callback_data = DASD_SLEEPON_START_TAG; 2286 dasd_add_request_tail(cqr); 2287 } 2288 2289 wait_event(generic_waitq, _wait_for_wakeup_queue(ccw_queue)); 2290 2291 rc = 0; 2292 list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) { 2293 if (__dasd_sleep_on_erp(cqr)) 2294 rc = 1; 2295 } 2296 if (rc) 2297 goto retry; 2298 2299 2300 return 0; 2301 } 2302 2303 /* 2304 * Queue a request to the tail of the device ccw_queue and wait for 2305 * it's completion. 2306 */ 2307 int dasd_sleep_on(struct dasd_ccw_req *cqr) 2308 { 2309 return _dasd_sleep_on(cqr, 0); 2310 } 2311 2312 /* 2313 * Start requests from a ccw_queue and wait for their completion. 2314 */ 2315 int dasd_sleep_on_queue(struct list_head *ccw_queue) 2316 { 2317 return _dasd_sleep_on_queue(ccw_queue, 0); 2318 } 2319 EXPORT_SYMBOL(dasd_sleep_on_queue); 2320 2321 /* 2322 * Queue a request to the tail of the device ccw_queue and wait 2323 * interruptible for it's completion. 2324 */ 2325 int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr) 2326 { 2327 return _dasd_sleep_on(cqr, 1); 2328 } 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 return rc; 2396 } 2397 2398 /* 2399 * Cancels a request that was started with dasd_sleep_on_req. 2400 * This is useful to timeout requests. The request will be 2401 * terminated if it is currently in i/o. 2402 * Returns 0 if request termination was successful 2403 * negative error code if termination failed 2404 * Cancellation of a request is an asynchronous operation! The calling 2405 * function has to wait until the request is properly returned via callback. 2406 */ 2407 int dasd_cancel_req(struct dasd_ccw_req *cqr) 2408 { 2409 struct dasd_device *device = cqr->startdev; 2410 unsigned long flags; 2411 int rc; 2412 2413 rc = 0; 2414 spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags); 2415 switch (cqr->status) { 2416 case DASD_CQR_QUEUED: 2417 /* request was not started - just set to cleared */ 2418 cqr->status = DASD_CQR_CLEARED; 2419 break; 2420 case DASD_CQR_IN_IO: 2421 /* request in IO - terminate IO and release again */ 2422 rc = device->discipline->term_IO(cqr); 2423 if (rc) { 2424 dev_err(&device->cdev->dev, 2425 "Cancelling request %p failed with rc=%d\n", 2426 cqr, rc); 2427 } else { 2428 cqr->stopclk = get_tod_clock(); 2429 } 2430 break; 2431 default: /* already finished or clear pending - do nothing */ 2432 break; 2433 } 2434 spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags); 2435 dasd_schedule_device_bh(device); 2436 return rc; 2437 } 2438 2439 /* 2440 * SECTION: Operations of the dasd_block layer. 2441 */ 2442 2443 /* 2444 * Timeout function for dasd_block. This is used when the block layer 2445 * is waiting for something that may not come reliably, (e.g. a state 2446 * change interrupt) 2447 */ 2448 static void dasd_block_timeout(unsigned long ptr) 2449 { 2450 unsigned long flags; 2451 struct dasd_block *block; 2452 2453 block = (struct dasd_block *) ptr; 2454 spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags); 2455 /* re-activate request queue */ 2456 dasd_device_remove_stop_bits(block->base, DASD_STOPPED_PENDING); 2457 spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags); 2458 dasd_schedule_block_bh(block); 2459 } 2460 2461 /* 2462 * Setup timeout for a dasd_block in jiffies. 2463 */ 2464 void dasd_block_set_timer(struct dasd_block *block, int expires) 2465 { 2466 if (expires == 0) 2467 del_timer(&block->timer); 2468 else 2469 mod_timer(&block->timer, jiffies + expires); 2470 } 2471 2472 /* 2473 * Clear timeout for a dasd_block. 2474 */ 2475 void dasd_block_clear_timer(struct dasd_block *block) 2476 { 2477 del_timer(&block->timer); 2478 } 2479 2480 /* 2481 * Process finished error recovery ccw. 2482 */ 2483 static void __dasd_process_erp(struct dasd_device *device, 2484 struct dasd_ccw_req *cqr) 2485 { 2486 dasd_erp_fn_t erp_fn; 2487 2488 if (cqr->status == DASD_CQR_DONE) 2489 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful"); 2490 else 2491 dev_err(&device->cdev->dev, "ERP failed for the DASD\n"); 2492 erp_fn = device->discipline->erp_postaction(cqr); 2493 erp_fn(cqr); 2494 } 2495 2496 /* 2497 * Fetch requests from the block device queue. 2498 */ 2499 static void __dasd_process_request_queue(struct dasd_block *block) 2500 { 2501 struct request_queue *queue; 2502 struct request *req; 2503 struct dasd_ccw_req *cqr; 2504 struct dasd_device *basedev; 2505 unsigned long flags; 2506 queue = block->request_queue; 2507 basedev = block->base; 2508 /* No queue ? Then there is nothing to do. */ 2509 if (queue == NULL) 2510 return; 2511 2512 /* 2513 * We requeue request from the block device queue to the ccw 2514 * queue only in two states. In state DASD_STATE_READY the 2515 * partition detection is done and we need to requeue requests 2516 * for that. State DASD_STATE_ONLINE is normal block device 2517 * operation. 2518 */ 2519 if (basedev->state < DASD_STATE_READY) { 2520 while ((req = blk_fetch_request(block->request_queue))) 2521 __blk_end_request_all(req, -EIO); 2522 return; 2523 } 2524 /* Now we try to fetch requests from the request queue */ 2525 while ((req = blk_peek_request(queue))) { 2526 if (basedev->features & DASD_FEATURE_READONLY && 2527 rq_data_dir(req) == WRITE) { 2528 DBF_DEV_EVENT(DBF_ERR, basedev, 2529 "Rejecting write request %p", 2530 req); 2531 blk_start_request(req); 2532 __blk_end_request_all(req, -EIO); 2533 continue; 2534 } 2535 if (test_bit(DASD_FLAG_ABORTALL, &basedev->flags) && 2536 (basedev->features & DASD_FEATURE_FAILFAST || 2537 blk_noretry_request(req))) { 2538 DBF_DEV_EVENT(DBF_ERR, basedev, 2539 "Rejecting failfast request %p", 2540 req); 2541 blk_start_request(req); 2542 __blk_end_request_all(req, -ETIMEDOUT); 2543 continue; 2544 } 2545 cqr = basedev->discipline->build_cp(basedev, block, req); 2546 if (IS_ERR(cqr)) { 2547 if (PTR_ERR(cqr) == -EBUSY) 2548 break; /* normal end condition */ 2549 if (PTR_ERR(cqr) == -ENOMEM) 2550 break; /* terminate request queue loop */ 2551 if (PTR_ERR(cqr) == -EAGAIN) { 2552 /* 2553 * The current request cannot be build right 2554 * now, we have to try later. If this request 2555 * is the head-of-queue we stop the device 2556 * for 1/2 second. 2557 */ 2558 if (!list_empty(&block->ccw_queue)) 2559 break; 2560 spin_lock_irqsave( 2561 get_ccwdev_lock(basedev->cdev), flags); 2562 dasd_device_set_stop_bits(basedev, 2563 DASD_STOPPED_PENDING); 2564 spin_unlock_irqrestore( 2565 get_ccwdev_lock(basedev->cdev), flags); 2566 dasd_block_set_timer(block, HZ/2); 2567 break; 2568 } 2569 DBF_DEV_EVENT(DBF_ERR, basedev, 2570 "CCW creation failed (rc=%ld) " 2571 "on request %p", 2572 PTR_ERR(cqr), req); 2573 blk_start_request(req); 2574 __blk_end_request_all(req, -EIO); 2575 continue; 2576 } 2577 /* 2578 * Note: callback is set to dasd_return_cqr_cb in 2579 * __dasd_block_start_head to cover erp requests as well 2580 */ 2581 cqr->callback_data = (void *) req; 2582 cqr->status = DASD_CQR_FILLED; 2583 req->completion_data = cqr; 2584 blk_start_request(req); 2585 list_add_tail(&cqr->blocklist, &block->ccw_queue); 2586 INIT_LIST_HEAD(&cqr->devlist); 2587 dasd_profile_start(block, cqr, req); 2588 } 2589 } 2590 2591 static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr) 2592 { 2593 struct request *req; 2594 int status; 2595 int error = 0; 2596 2597 req = (struct request *) cqr->callback_data; 2598 dasd_profile_end(cqr->block, cqr, req); 2599 status = cqr->block->base->discipline->free_cp(cqr, req); 2600 if (status < 0) 2601 error = status; 2602 else if (status == 0) { 2603 if (cqr->intrc == -EPERM) 2604 error = -EBADE; 2605 else if (cqr->intrc == -ENOLINK || 2606 cqr->intrc == -ETIMEDOUT) 2607 error = cqr->intrc; 2608 else 2609 error = -EIO; 2610 } 2611 __blk_end_request_all(req, error); 2612 } 2613 2614 /* 2615 * Process ccw request queue. 2616 */ 2617 static void __dasd_process_block_ccw_queue(struct dasd_block *block, 2618 struct list_head *final_queue) 2619 { 2620 struct list_head *l, *n; 2621 struct dasd_ccw_req *cqr; 2622 dasd_erp_fn_t erp_fn; 2623 unsigned long flags; 2624 struct dasd_device *base = block->base; 2625 2626 restart: 2627 /* Process request with final status. */ 2628 list_for_each_safe(l, n, &block->ccw_queue) { 2629 cqr = list_entry(l, struct dasd_ccw_req, blocklist); 2630 if (cqr->status != DASD_CQR_DONE && 2631 cqr->status != DASD_CQR_FAILED && 2632 cqr->status != DASD_CQR_NEED_ERP && 2633 cqr->status != DASD_CQR_TERMINATED) 2634 continue; 2635 2636 if (cqr->status == DASD_CQR_TERMINATED) { 2637 base->discipline->handle_terminated_request(cqr); 2638 goto restart; 2639 } 2640 2641 /* Process requests that may be recovered */ 2642 if (cqr->status == DASD_CQR_NEED_ERP) { 2643 erp_fn = base->discipline->erp_action(cqr); 2644 if (IS_ERR(erp_fn(cqr))) 2645 continue; 2646 goto restart; 2647 } 2648 2649 /* log sense for fatal error */ 2650 if (cqr->status == DASD_CQR_FAILED) { 2651 dasd_log_sense(cqr, &cqr->irb); 2652 } 2653 2654 /* First of all call extended error reporting. */ 2655 if (dasd_eer_enabled(base) && 2656 cqr->status == DASD_CQR_FAILED) { 2657 dasd_eer_write(base, cqr, DASD_EER_FATALERROR); 2658 2659 /* restart request */ 2660 cqr->status = DASD_CQR_FILLED; 2661 cqr->retries = 255; 2662 spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags); 2663 dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE); 2664 spin_unlock_irqrestore(get_ccwdev_lock(base->cdev), 2665 flags); 2666 goto restart; 2667 } 2668 2669 /* Process finished ERP request. */ 2670 if (cqr->refers) { 2671 __dasd_process_erp(base, cqr); 2672 goto restart; 2673 } 2674 2675 /* Rechain finished requests to final queue */ 2676 cqr->endclk = get_tod_clock(); 2677 list_move_tail(&cqr->blocklist, final_queue); 2678 } 2679 } 2680 2681 static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data) 2682 { 2683 dasd_schedule_block_bh(cqr->block); 2684 } 2685 2686 static void __dasd_block_start_head(struct dasd_block *block) 2687 { 2688 struct dasd_ccw_req *cqr; 2689 2690 if (list_empty(&block->ccw_queue)) 2691 return; 2692 /* We allways begin with the first requests on the queue, as some 2693 * of previously started requests have to be enqueued on a 2694 * dasd_device again for error recovery. 2695 */ 2696 list_for_each_entry(cqr, &block->ccw_queue, blocklist) { 2697 if (cqr->status != DASD_CQR_FILLED) 2698 continue; 2699 if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) && 2700 !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) { 2701 cqr->status = DASD_CQR_FAILED; 2702 cqr->intrc = -EPERM; 2703 dasd_schedule_block_bh(block); 2704 continue; 2705 } 2706 /* Non-temporary stop condition will trigger fail fast */ 2707 if (block->base->stopped & ~DASD_STOPPED_PENDING && 2708 test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) && 2709 (!dasd_eer_enabled(block->base))) { 2710 cqr->status = DASD_CQR_FAILED; 2711 cqr->intrc = -ENOLINK; 2712 dasd_schedule_block_bh(block); 2713 continue; 2714 } 2715 /* Don't try to start requests if device is stopped */ 2716 if (block->base->stopped) 2717 return; 2718 2719 /* just a fail safe check, should not happen */ 2720 if (!cqr->startdev) 2721 cqr->startdev = block->base; 2722 2723 /* make sure that the requests we submit find their way back */ 2724 cqr->callback = dasd_return_cqr_cb; 2725 2726 dasd_add_request_tail(cqr); 2727 } 2728 } 2729 2730 /* 2731 * Central dasd_block layer routine. Takes requests from the generic 2732 * block layer request queue, creates ccw requests, enqueues them on 2733 * a dasd_device and processes ccw requests that have been returned. 2734 */ 2735 static void dasd_block_tasklet(struct dasd_block *block) 2736 { 2737 struct list_head final_queue; 2738 struct list_head *l, *n; 2739 struct dasd_ccw_req *cqr; 2740 2741 atomic_set(&block->tasklet_scheduled, 0); 2742 INIT_LIST_HEAD(&final_queue); 2743 spin_lock(&block->queue_lock); 2744 /* Finish off requests on ccw queue */ 2745 __dasd_process_block_ccw_queue(block, &final_queue); 2746 spin_unlock(&block->queue_lock); 2747 /* Now call the callback function of requests with final status */ 2748 spin_lock_irq(&block->request_queue_lock); 2749 list_for_each_safe(l, n, &final_queue) { 2750 cqr = list_entry(l, struct dasd_ccw_req, blocklist); 2751 list_del_init(&cqr->blocklist); 2752 __dasd_cleanup_cqr(cqr); 2753 } 2754 spin_lock(&block->queue_lock); 2755 /* Get new request from the block device request queue */ 2756 __dasd_process_request_queue(block); 2757 /* Now check if the head of the ccw queue needs to be started. */ 2758 __dasd_block_start_head(block); 2759 spin_unlock(&block->queue_lock); 2760 spin_unlock_irq(&block->request_queue_lock); 2761 if (waitqueue_active(&shutdown_waitq)) 2762 wake_up(&shutdown_waitq); 2763 dasd_put_device(block->base); 2764 } 2765 2766 static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data) 2767 { 2768 wake_up(&dasd_flush_wq); 2769 } 2770 2771 /* 2772 * Requeue a request back to the block request queue 2773 * only works for block requests 2774 */ 2775 static int _dasd_requeue_request(struct dasd_ccw_req *cqr) 2776 { 2777 struct dasd_block *block = cqr->block; 2778 struct request *req; 2779 unsigned long flags; 2780 2781 if (!block) 2782 return -EINVAL; 2783 spin_lock_irqsave(&block->queue_lock, flags); 2784 req = (struct request *) cqr->callback_data; 2785 blk_requeue_request(block->request_queue, req); 2786 spin_unlock_irqrestore(&block->queue_lock, flags); 2787 2788 return 0; 2789 } 2790 2791 /* 2792 * Go through all request on the dasd_block request queue, cancel them 2793 * on the respective dasd_device, and return them to the generic 2794 * block layer. 2795 */ 2796 static int dasd_flush_block_queue(struct dasd_block *block) 2797 { 2798 struct dasd_ccw_req *cqr, *n; 2799 int rc, i; 2800 struct list_head flush_queue; 2801 2802 INIT_LIST_HEAD(&flush_queue); 2803 spin_lock_bh(&block->queue_lock); 2804 rc = 0; 2805 restart: 2806 list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) { 2807 /* if this request currently owned by a dasd_device cancel it */ 2808 if (cqr->status >= DASD_CQR_QUEUED) 2809 rc = dasd_cancel_req(cqr); 2810 if (rc < 0) 2811 break; 2812 /* Rechain request (including erp chain) so it won't be 2813 * touched by the dasd_block_tasklet anymore. 2814 * Replace the callback so we notice when the request 2815 * is returned from the dasd_device layer. 2816 */ 2817 cqr->callback = _dasd_wake_block_flush_cb; 2818 for (i = 0; cqr != NULL; cqr = cqr->refers, i++) 2819 list_move_tail(&cqr->blocklist, &flush_queue); 2820 if (i > 1) 2821 /* moved more than one request - need to restart */ 2822 goto restart; 2823 } 2824 spin_unlock_bh(&block->queue_lock); 2825 /* Now call the callback function of flushed requests */ 2826 restart_cb: 2827 list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) { 2828 wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED)); 2829 /* Process finished ERP request. */ 2830 if (cqr->refers) { 2831 spin_lock_bh(&block->queue_lock); 2832 __dasd_process_erp(block->base, cqr); 2833 spin_unlock_bh(&block->queue_lock); 2834 /* restart list_for_xx loop since dasd_process_erp 2835 * might remove multiple elements */ 2836 goto restart_cb; 2837 } 2838 /* call the callback function */ 2839 spin_lock_irq(&block->request_queue_lock); 2840 cqr->endclk = get_tod_clock(); 2841 list_del_init(&cqr->blocklist); 2842 __dasd_cleanup_cqr(cqr); 2843 spin_unlock_irq(&block->request_queue_lock); 2844 } 2845 return rc; 2846 } 2847 2848 /* 2849 * Schedules a call to dasd_tasklet over the device tasklet. 2850 */ 2851 void dasd_schedule_block_bh(struct dasd_block *block) 2852 { 2853 /* Protect against rescheduling. */ 2854 if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0) 2855 return; 2856 /* life cycle of block is bound to it's base device */ 2857 dasd_get_device(block->base); 2858 tasklet_hi_schedule(&block->tasklet); 2859 } 2860 2861 2862 /* 2863 * SECTION: external block device operations 2864 * (request queue handling, open, release, etc.) 2865 */ 2866 2867 /* 2868 * Dasd request queue function. Called from ll_rw_blk.c 2869 */ 2870 static void do_dasd_request(struct request_queue *queue) 2871 { 2872 struct dasd_block *block; 2873 2874 block = queue->queuedata; 2875 spin_lock(&block->queue_lock); 2876 /* Get new request from the block device request queue */ 2877 __dasd_process_request_queue(block); 2878 /* Now check if the head of the ccw queue needs to be started. */ 2879 __dasd_block_start_head(block); 2880 spin_unlock(&block->queue_lock); 2881 } 2882 2883 /* 2884 * Block timeout callback, called from the block layer 2885 * 2886 * request_queue lock is held on entry. 2887 * 2888 * Return values: 2889 * BLK_EH_RESET_TIMER if the request should be left running 2890 * BLK_EH_NOT_HANDLED if the request is handled or terminated 2891 * by the driver. 2892 */ 2893 enum blk_eh_timer_return dasd_times_out(struct request *req) 2894 { 2895 struct dasd_ccw_req *cqr = req->completion_data; 2896 struct dasd_block *block = req->q->queuedata; 2897 struct dasd_device *device; 2898 int rc = 0; 2899 2900 if (!cqr) 2901 return BLK_EH_NOT_HANDLED; 2902 2903 device = cqr->startdev ? cqr->startdev : block->base; 2904 if (!device->blk_timeout) 2905 return BLK_EH_RESET_TIMER; 2906 DBF_DEV_EVENT(DBF_WARNING, device, 2907 " dasd_times_out cqr %p status %x", 2908 cqr, cqr->status); 2909 2910 spin_lock(&block->queue_lock); 2911 spin_lock(get_ccwdev_lock(device->cdev)); 2912 cqr->retries = -1; 2913 cqr->intrc = -ETIMEDOUT; 2914 if (cqr->status >= DASD_CQR_QUEUED) { 2915 spin_unlock(get_ccwdev_lock(device->cdev)); 2916 rc = dasd_cancel_req(cqr); 2917 } else if (cqr->status == DASD_CQR_FILLED || 2918 cqr->status == DASD_CQR_NEED_ERP) { 2919 cqr->status = DASD_CQR_TERMINATED; 2920 spin_unlock(get_ccwdev_lock(device->cdev)); 2921 } else if (cqr->status == DASD_CQR_IN_ERP) { 2922 struct dasd_ccw_req *searchcqr, *nextcqr, *tmpcqr; 2923 2924 list_for_each_entry_safe(searchcqr, nextcqr, 2925 &block->ccw_queue, blocklist) { 2926 tmpcqr = searchcqr; 2927 while (tmpcqr->refers) 2928 tmpcqr = tmpcqr->refers; 2929 if (tmpcqr != cqr) 2930 continue; 2931 /* searchcqr is an ERP request for cqr */ 2932 searchcqr->retries = -1; 2933 searchcqr->intrc = -ETIMEDOUT; 2934 if (searchcqr->status >= DASD_CQR_QUEUED) { 2935 spin_unlock(get_ccwdev_lock(device->cdev)); 2936 rc = dasd_cancel_req(searchcqr); 2937 spin_lock(get_ccwdev_lock(device->cdev)); 2938 } else if ((searchcqr->status == DASD_CQR_FILLED) || 2939 (searchcqr->status == DASD_CQR_NEED_ERP)) { 2940 searchcqr->status = DASD_CQR_TERMINATED; 2941 rc = 0; 2942 } else if (searchcqr->status == DASD_CQR_IN_ERP) { 2943 /* 2944 * Shouldn't happen; most recent ERP 2945 * request is at the front of queue 2946 */ 2947 continue; 2948 } 2949 break; 2950 } 2951 spin_unlock(get_ccwdev_lock(device->cdev)); 2952 } 2953 dasd_schedule_block_bh(block); 2954 spin_unlock(&block->queue_lock); 2955 2956 return rc ? BLK_EH_RESET_TIMER : BLK_EH_NOT_HANDLED; 2957 } 2958 2959 /* 2960 * Allocate and initialize request queue and default I/O scheduler. 2961 */ 2962 static int dasd_alloc_queue(struct dasd_block *block) 2963 { 2964 int rc; 2965 2966 block->request_queue = blk_init_queue(do_dasd_request, 2967 &block->request_queue_lock); 2968 if (block->request_queue == NULL) 2969 return -ENOMEM; 2970 2971 block->request_queue->queuedata = block; 2972 2973 elevator_exit(block->request_queue->elevator); 2974 block->request_queue->elevator = NULL; 2975 rc = elevator_init(block->request_queue, "deadline"); 2976 if (rc) { 2977 blk_cleanup_queue(block->request_queue); 2978 return rc; 2979 } 2980 return 0; 2981 } 2982 2983 /* 2984 * Allocate and initialize request queue. 2985 */ 2986 static void dasd_setup_queue(struct dasd_block *block) 2987 { 2988 int max; 2989 2990 if (block->base->features & DASD_FEATURE_USERAW) { 2991 /* 2992 * the max_blocks value for raw_track access is 256 2993 * it is higher than the native ECKD value because we 2994 * only need one ccw per track 2995 * so the max_hw_sectors are 2996 * 2048 x 512B = 1024kB = 16 tracks 2997 */ 2998 max = 2048; 2999 } else { 3000 max = block->base->discipline->max_blocks << block->s2b_shift; 3001 } 3002 blk_queue_logical_block_size(block->request_queue, 3003 block->bp_block); 3004 blk_queue_max_hw_sectors(block->request_queue, max); 3005 blk_queue_max_segments(block->request_queue, -1L); 3006 /* with page sized segments we can translate each segement into 3007 * one idaw/tidaw 3008 */ 3009 blk_queue_max_segment_size(block->request_queue, PAGE_SIZE); 3010 blk_queue_segment_boundary(block->request_queue, PAGE_SIZE - 1); 3011 } 3012 3013 /* 3014 * Deactivate and free request queue. 3015 */ 3016 static void dasd_free_queue(struct dasd_block *block) 3017 { 3018 if (block->request_queue) { 3019 blk_cleanup_queue(block->request_queue); 3020 block->request_queue = NULL; 3021 } 3022 } 3023 3024 /* 3025 * Flush request on the request queue. 3026 */ 3027 static void dasd_flush_request_queue(struct dasd_block *block) 3028 { 3029 struct request *req; 3030 3031 if (!block->request_queue) 3032 return; 3033 3034 spin_lock_irq(&block->request_queue_lock); 3035 while ((req = blk_fetch_request(block->request_queue))) 3036 __blk_end_request_all(req, -EIO); 3037 spin_unlock_irq(&block->request_queue_lock); 3038 } 3039 3040 static int dasd_open(struct block_device *bdev, fmode_t mode) 3041 { 3042 struct dasd_device *base; 3043 int rc; 3044 3045 base = dasd_device_from_gendisk(bdev->bd_disk); 3046 if (!base) 3047 return -ENODEV; 3048 3049 atomic_inc(&base->block->open_count); 3050 if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) { 3051 rc = -ENODEV; 3052 goto unlock; 3053 } 3054 3055 if (!try_module_get(base->discipline->owner)) { 3056 rc = -EINVAL; 3057 goto unlock; 3058 } 3059 3060 if (dasd_probeonly) { 3061 dev_info(&base->cdev->dev, 3062 "Accessing the DASD failed because it is in " 3063 "probeonly mode\n"); 3064 rc = -EPERM; 3065 goto out; 3066 } 3067 3068 if (base->state <= DASD_STATE_BASIC) { 3069 DBF_DEV_EVENT(DBF_ERR, base, " %s", 3070 " Cannot open unrecognized device"); 3071 rc = -ENODEV; 3072 goto out; 3073 } 3074 3075 if ((mode & FMODE_WRITE) && 3076 (test_bit(DASD_FLAG_DEVICE_RO, &base->flags) || 3077 (base->features & DASD_FEATURE_READONLY))) { 3078 rc = -EROFS; 3079 goto out; 3080 } 3081 3082 dasd_put_device(base); 3083 return 0; 3084 3085 out: 3086 module_put(base->discipline->owner); 3087 unlock: 3088 atomic_dec(&base->block->open_count); 3089 dasd_put_device(base); 3090 return rc; 3091 } 3092 3093 static void dasd_release(struct gendisk *disk, fmode_t mode) 3094 { 3095 struct dasd_device *base = dasd_device_from_gendisk(disk); 3096 if (base) { 3097 atomic_dec(&base->block->open_count); 3098 module_put(base->discipline->owner); 3099 dasd_put_device(base); 3100 } 3101 } 3102 3103 /* 3104 * Return disk geometry. 3105 */ 3106 static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo) 3107 { 3108 struct dasd_device *base; 3109 3110 base = dasd_device_from_gendisk(bdev->bd_disk); 3111 if (!base) 3112 return -ENODEV; 3113 3114 if (!base->discipline || 3115 !base->discipline->fill_geometry) { 3116 dasd_put_device(base); 3117 return -EINVAL; 3118 } 3119 base->discipline->fill_geometry(base->block, geo); 3120 geo->start = get_start_sect(bdev) >> base->block->s2b_shift; 3121 dasd_put_device(base); 3122 return 0; 3123 } 3124 3125 const struct block_device_operations 3126 dasd_device_operations = { 3127 .owner = THIS_MODULE, 3128 .open = dasd_open, 3129 .release = dasd_release, 3130 .ioctl = dasd_ioctl, 3131 .compat_ioctl = dasd_ioctl, 3132 .getgeo = dasd_getgeo, 3133 }; 3134 3135 /******************************************************************************* 3136 * end of block device operations 3137 */ 3138 3139 static void 3140 dasd_exit(void) 3141 { 3142 #ifdef CONFIG_PROC_FS 3143 dasd_proc_exit(); 3144 #endif 3145 dasd_eer_exit(); 3146 if (dasd_page_cache != NULL) { 3147 kmem_cache_destroy(dasd_page_cache); 3148 dasd_page_cache = NULL; 3149 } 3150 dasd_gendisk_exit(); 3151 dasd_devmap_exit(); 3152 if (dasd_debug_area != NULL) { 3153 debug_unregister(dasd_debug_area); 3154 dasd_debug_area = NULL; 3155 } 3156 dasd_statistics_removeroot(); 3157 } 3158 3159 /* 3160 * SECTION: common functions for ccw_driver use 3161 */ 3162 3163 /* 3164 * Is the device read-only? 3165 * Note that this function does not report the setting of the 3166 * readonly device attribute, but how it is configured in z/VM. 3167 */ 3168 int dasd_device_is_ro(struct dasd_device *device) 3169 { 3170 struct ccw_dev_id dev_id; 3171 struct diag210 diag_data; 3172 int rc; 3173 3174 if (!MACHINE_IS_VM) 3175 return 0; 3176 ccw_device_get_id(device->cdev, &dev_id); 3177 memset(&diag_data, 0, sizeof(diag_data)); 3178 diag_data.vrdcdvno = dev_id.devno; 3179 diag_data.vrdclen = sizeof(diag_data); 3180 rc = diag210(&diag_data); 3181 if (rc == 0 || rc == 2) { 3182 return diag_data.vrdcvfla & 0x80; 3183 } else { 3184 DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d", 3185 dev_id.devno, rc); 3186 return 0; 3187 } 3188 } 3189 EXPORT_SYMBOL_GPL(dasd_device_is_ro); 3190 3191 static void dasd_generic_auto_online(void *data, async_cookie_t cookie) 3192 { 3193 struct ccw_device *cdev = data; 3194 int ret; 3195 3196 ret = ccw_device_set_online(cdev); 3197 if (ret) 3198 pr_warning("%s: Setting the DASD online failed with rc=%d\n", 3199 dev_name(&cdev->dev), ret); 3200 } 3201 3202 /* 3203 * Initial attempt at a probe function. this can be simplified once 3204 * the other detection code is gone. 3205 */ 3206 int dasd_generic_probe(struct ccw_device *cdev, 3207 struct dasd_discipline *discipline) 3208 { 3209 int ret; 3210 3211 ret = dasd_add_sysfs_files(cdev); 3212 if (ret) { 3213 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s", 3214 "dasd_generic_probe: could not add " 3215 "sysfs entries"); 3216 return ret; 3217 } 3218 cdev->handler = &dasd_int_handler; 3219 3220 /* 3221 * Automatically online either all dasd devices (dasd_autodetect) 3222 * or all devices specified with dasd= parameters during 3223 * initial probe. 3224 */ 3225 if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) || 3226 (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0)) 3227 async_schedule(dasd_generic_auto_online, cdev); 3228 return 0; 3229 } 3230 3231 /* 3232 * This will one day be called from a global not_oper handler. 3233 * It is also used by driver_unregister during module unload. 3234 */ 3235 void dasd_generic_remove(struct ccw_device *cdev) 3236 { 3237 struct dasd_device *device; 3238 struct dasd_block *block; 3239 3240 cdev->handler = NULL; 3241 3242 device = dasd_device_from_cdev(cdev); 3243 if (IS_ERR(device)) { 3244 dasd_remove_sysfs_files(cdev); 3245 return; 3246 } 3247 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags) && 3248 !test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) { 3249 /* Already doing offline processing */ 3250 dasd_put_device(device); 3251 dasd_remove_sysfs_files(cdev); 3252 return; 3253 } 3254 /* 3255 * This device is removed unconditionally. Set offline 3256 * flag to prevent dasd_open from opening it while it is 3257 * no quite down yet. 3258 */ 3259 dasd_set_target_state(device, DASD_STATE_NEW); 3260 /* dasd_delete_device destroys the device reference. */ 3261 block = device->block; 3262 dasd_delete_device(device); 3263 /* 3264 * life cycle of block is bound to device, so delete it after 3265 * device was safely removed 3266 */ 3267 if (block) 3268 dasd_free_block(block); 3269 3270 dasd_remove_sysfs_files(cdev); 3271 } 3272 3273 /* 3274 * Activate a device. This is called from dasd_{eckd,fba}_probe() when either 3275 * the device is detected for the first time and is supposed to be used 3276 * or the user has started activation through sysfs. 3277 */ 3278 int dasd_generic_set_online(struct ccw_device *cdev, 3279 struct dasd_discipline *base_discipline) 3280 { 3281 struct dasd_discipline *discipline; 3282 struct dasd_device *device; 3283 int rc; 3284 3285 /* first online clears initial online feature flag */ 3286 dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0); 3287 device = dasd_create_device(cdev); 3288 if (IS_ERR(device)) 3289 return PTR_ERR(device); 3290 3291 discipline = base_discipline; 3292 if (device->features & DASD_FEATURE_USEDIAG) { 3293 if (!dasd_diag_discipline_pointer) { 3294 pr_warning("%s Setting the DASD online failed because " 3295 "of missing DIAG discipline\n", 3296 dev_name(&cdev->dev)); 3297 dasd_delete_device(device); 3298 return -ENODEV; 3299 } 3300 discipline = dasd_diag_discipline_pointer; 3301 } 3302 if (!try_module_get(base_discipline->owner)) { 3303 dasd_delete_device(device); 3304 return -EINVAL; 3305 } 3306 if (!try_module_get(discipline->owner)) { 3307 module_put(base_discipline->owner); 3308 dasd_delete_device(device); 3309 return -EINVAL; 3310 } 3311 device->base_discipline = base_discipline; 3312 device->discipline = discipline; 3313 3314 /* check_device will allocate block device if necessary */ 3315 rc = discipline->check_device(device); 3316 if (rc) { 3317 pr_warning("%s Setting the DASD online with discipline %s " 3318 "failed with rc=%i\n", 3319 dev_name(&cdev->dev), discipline->name, rc); 3320 module_put(discipline->owner); 3321 module_put(base_discipline->owner); 3322 dasd_delete_device(device); 3323 return rc; 3324 } 3325 3326 dasd_set_target_state(device, DASD_STATE_ONLINE); 3327 if (device->state <= DASD_STATE_KNOWN) { 3328 pr_warning("%s Setting the DASD online failed because of a " 3329 "missing discipline\n", dev_name(&cdev->dev)); 3330 rc = -ENODEV; 3331 dasd_set_target_state(device, DASD_STATE_NEW); 3332 if (device->block) 3333 dasd_free_block(device->block); 3334 dasd_delete_device(device); 3335 } else 3336 pr_debug("dasd_generic device %s found\n", 3337 dev_name(&cdev->dev)); 3338 3339 wait_event(dasd_init_waitq, _wait_for_device(device)); 3340 3341 dasd_put_device(device); 3342 return rc; 3343 } 3344 3345 int dasd_generic_set_offline(struct ccw_device *cdev) 3346 { 3347 struct dasd_device *device; 3348 struct dasd_block *block; 3349 int max_count, open_count, rc; 3350 3351 rc = 0; 3352 device = dasd_device_from_cdev(cdev); 3353 if (IS_ERR(device)) 3354 return PTR_ERR(device); 3355 3356 /* 3357 * We must make sure that this device is currently not in use. 3358 * The open_count is increased for every opener, that includes 3359 * the blkdev_get in dasd_scan_partitions. We are only interested 3360 * in the other openers. 3361 */ 3362 if (device->block) { 3363 max_count = device->block->bdev ? 0 : -1; 3364 open_count = atomic_read(&device->block->open_count); 3365 if (open_count > max_count) { 3366 if (open_count > 0) 3367 pr_warning("%s: The DASD cannot be set offline " 3368 "with open count %i\n", 3369 dev_name(&cdev->dev), open_count); 3370 else 3371 pr_warning("%s: The DASD cannot be set offline " 3372 "while it is in use\n", 3373 dev_name(&cdev->dev)); 3374 clear_bit(DASD_FLAG_OFFLINE, &device->flags); 3375 dasd_put_device(device); 3376 return -EBUSY; 3377 } 3378 } 3379 3380 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) { 3381 /* 3382 * safe offline allready running 3383 * could only be called by normal offline so safe_offline flag 3384 * needs to be removed to run normal offline and kill all I/O 3385 */ 3386 if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) { 3387 /* Already doing normal offline processing */ 3388 dasd_put_device(device); 3389 return -EBUSY; 3390 } else 3391 clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags); 3392 3393 } else 3394 if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) { 3395 /* Already doing offline processing */ 3396 dasd_put_device(device); 3397 return -EBUSY; 3398 } 3399 3400 /* 3401 * if safe_offline called set safe_offline_running flag and 3402 * clear safe_offline so that a call to normal offline 3403 * can overrun safe_offline processing 3404 */ 3405 if (test_and_clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags) && 3406 !test_and_set_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) { 3407 /* 3408 * If we want to set the device safe offline all IO operations 3409 * should be finished before continuing the offline process 3410 * so sync bdev first and then wait for our queues to become 3411 * empty 3412 */ 3413 /* sync blockdev and partitions */ 3414 rc = fsync_bdev(device->block->bdev); 3415 if (rc != 0) 3416 goto interrupted; 3417 3418 /* schedule device tasklet and wait for completion */ 3419 dasd_schedule_device_bh(device); 3420 rc = wait_event_interruptible(shutdown_waitq, 3421 _wait_for_empty_queues(device)); 3422 if (rc != 0) 3423 goto interrupted; 3424 } 3425 3426 set_bit(DASD_FLAG_OFFLINE, &device->flags); 3427 dasd_set_target_state(device, DASD_STATE_NEW); 3428 /* dasd_delete_device destroys the device reference. */ 3429 block = device->block; 3430 dasd_delete_device(device); 3431 /* 3432 * life cycle of block is bound to device, so delete it after 3433 * device was safely removed 3434 */ 3435 if (block) 3436 dasd_free_block(block); 3437 return 0; 3438 3439 interrupted: 3440 /* interrupted by signal */ 3441 clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags); 3442 clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags); 3443 clear_bit(DASD_FLAG_OFFLINE, &device->flags); 3444 dasd_put_device(device); 3445 return rc; 3446 } 3447 3448 int dasd_generic_last_path_gone(struct dasd_device *device) 3449 { 3450 struct dasd_ccw_req *cqr; 3451 3452 dev_warn(&device->cdev->dev, "No operational channel path is left " 3453 "for the device\n"); 3454 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone"); 3455 /* First of all call extended error reporting. */ 3456 dasd_eer_write(device, NULL, DASD_EER_NOPATH); 3457 3458 if (device->state < DASD_STATE_BASIC) 3459 return 0; 3460 /* Device is active. We want to keep it. */ 3461 list_for_each_entry(cqr, &device->ccw_queue, devlist) 3462 if ((cqr->status == DASD_CQR_IN_IO) || 3463 (cqr->status == DASD_CQR_CLEAR_PENDING)) { 3464 cqr->status = DASD_CQR_QUEUED; 3465 cqr->retries++; 3466 } 3467 dasd_device_set_stop_bits(device, DASD_STOPPED_DC_WAIT); 3468 dasd_device_clear_timer(device); 3469 dasd_schedule_device_bh(device); 3470 return 1; 3471 } 3472 EXPORT_SYMBOL_GPL(dasd_generic_last_path_gone); 3473 3474 int dasd_generic_path_operational(struct dasd_device *device) 3475 { 3476 dev_info(&device->cdev->dev, "A channel path to the device has become " 3477 "operational\n"); 3478 DBF_DEV_EVENT(DBF_WARNING, device, "%s", "path operational"); 3479 dasd_device_remove_stop_bits(device, DASD_STOPPED_DC_WAIT); 3480 if (device->stopped & DASD_UNRESUMED_PM) { 3481 dasd_device_remove_stop_bits(device, DASD_UNRESUMED_PM); 3482 dasd_restore_device(device); 3483 return 1; 3484 } 3485 dasd_schedule_device_bh(device); 3486 if (device->block) 3487 dasd_schedule_block_bh(device->block); 3488 return 1; 3489 } 3490 EXPORT_SYMBOL_GPL(dasd_generic_path_operational); 3491 3492 int dasd_generic_notify(struct ccw_device *cdev, int event) 3493 { 3494 struct dasd_device *device; 3495 int ret; 3496 3497 device = dasd_device_from_cdev_locked(cdev); 3498 if (IS_ERR(device)) 3499 return 0; 3500 ret = 0; 3501 switch (event) { 3502 case CIO_GONE: 3503 case CIO_BOXED: 3504 case CIO_NO_PATH: 3505 device->path_data.opm = 0; 3506 device->path_data.ppm = 0; 3507 device->path_data.npm = 0; 3508 ret = dasd_generic_last_path_gone(device); 3509 break; 3510 case CIO_OPER: 3511 ret = 1; 3512 if (device->path_data.opm) 3513 ret = dasd_generic_path_operational(device); 3514 break; 3515 } 3516 dasd_put_device(device); 3517 return ret; 3518 } 3519 3520 void dasd_generic_path_event(struct ccw_device *cdev, int *path_event) 3521 { 3522 int chp; 3523 __u8 oldopm, eventlpm; 3524 struct dasd_device *device; 3525 3526 device = dasd_device_from_cdev_locked(cdev); 3527 if (IS_ERR(device)) 3528 return; 3529 for (chp = 0; chp < 8; chp++) { 3530 eventlpm = 0x80 >> chp; 3531 if (path_event[chp] & PE_PATH_GONE) { 3532 oldopm = device->path_data.opm; 3533 device->path_data.opm &= ~eventlpm; 3534 device->path_data.ppm &= ~eventlpm; 3535 device->path_data.npm &= ~eventlpm; 3536 if (oldopm && !device->path_data.opm) { 3537 dev_warn(&device->cdev->dev, 3538 "No verified channel paths remain " 3539 "for the device\n"); 3540 DBF_DEV_EVENT(DBF_WARNING, device, 3541 "%s", "last verified path gone"); 3542 dasd_eer_write(device, NULL, DASD_EER_NOPATH); 3543 dasd_device_set_stop_bits(device, 3544 DASD_STOPPED_DC_WAIT); 3545 } 3546 } 3547 if (path_event[chp] & PE_PATH_AVAILABLE) { 3548 device->path_data.opm &= ~eventlpm; 3549 device->path_data.ppm &= ~eventlpm; 3550 device->path_data.npm &= ~eventlpm; 3551 device->path_data.tbvpm |= eventlpm; 3552 dasd_schedule_device_bh(device); 3553 } 3554 if (path_event[chp] & PE_PATHGROUP_ESTABLISHED) { 3555 if (!(device->path_data.opm & eventlpm) && 3556 !(device->path_data.tbvpm & eventlpm)) { 3557 /* 3558 * we can not establish a pathgroup on an 3559 * unavailable path, so trigger a path 3560 * verification first 3561 */ 3562 device->path_data.tbvpm |= eventlpm; 3563 dasd_schedule_device_bh(device); 3564 } 3565 DBF_DEV_EVENT(DBF_WARNING, device, "%s", 3566 "Pathgroup re-established\n"); 3567 if (device->discipline->kick_validate) 3568 device->discipline->kick_validate(device); 3569 } 3570 } 3571 dasd_put_device(device); 3572 } 3573 EXPORT_SYMBOL_GPL(dasd_generic_path_event); 3574 3575 int dasd_generic_verify_path(struct dasd_device *device, __u8 lpm) 3576 { 3577 if (!device->path_data.opm && lpm) { 3578 device->path_data.opm = lpm; 3579 dasd_generic_path_operational(device); 3580 } else 3581 device->path_data.opm |= lpm; 3582 return 0; 3583 } 3584 EXPORT_SYMBOL_GPL(dasd_generic_verify_path); 3585 3586 3587 int dasd_generic_pm_freeze(struct ccw_device *cdev) 3588 { 3589 struct dasd_device *device = dasd_device_from_cdev(cdev); 3590 struct list_head freeze_queue; 3591 struct dasd_ccw_req *cqr, *n; 3592 struct dasd_ccw_req *refers; 3593 int rc; 3594 3595 if (IS_ERR(device)) 3596 return PTR_ERR(device); 3597 3598 /* mark device as suspended */ 3599 set_bit(DASD_FLAG_SUSPENDED, &device->flags); 3600 3601 if (device->discipline->freeze) 3602 rc = device->discipline->freeze(device); 3603 3604 /* disallow new I/O */ 3605 dasd_device_set_stop_bits(device, DASD_STOPPED_PM); 3606 3607 /* clear active requests and requeue them to block layer if possible */ 3608 INIT_LIST_HEAD(&freeze_queue); 3609 spin_lock_irq(get_ccwdev_lock(cdev)); 3610 rc = 0; 3611 list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) { 3612 /* Check status and move request to flush_queue */ 3613 if (cqr->status == DASD_CQR_IN_IO) { 3614 rc = device->discipline->term_IO(cqr); 3615 if (rc) { 3616 /* unable to terminate requeust */ 3617 dev_err(&device->cdev->dev, 3618 "Unable to terminate request %p " 3619 "on suspend\n", cqr); 3620 spin_unlock_irq(get_ccwdev_lock(cdev)); 3621 dasd_put_device(device); 3622 return rc; 3623 } 3624 } 3625 list_move_tail(&cqr->devlist, &freeze_queue); 3626 } 3627 spin_unlock_irq(get_ccwdev_lock(cdev)); 3628 3629 list_for_each_entry_safe(cqr, n, &freeze_queue, devlist) { 3630 wait_event(dasd_flush_wq, 3631 (cqr->status != DASD_CQR_CLEAR_PENDING)); 3632 if (cqr->status == DASD_CQR_CLEARED) 3633 cqr->status = DASD_CQR_QUEUED; 3634 3635 /* requeue requests to blocklayer will only work for 3636 block device requests */ 3637 if (_dasd_requeue_request(cqr)) 3638 continue; 3639 3640 /* remove requests from device and block queue */ 3641 list_del_init(&cqr->devlist); 3642 while (cqr->refers != NULL) { 3643 refers = cqr->refers; 3644 /* remove the request from the block queue */ 3645 list_del(&cqr->blocklist); 3646 /* free the finished erp request */ 3647 dasd_free_erp_request(cqr, cqr->memdev); 3648 cqr = refers; 3649 } 3650 if (cqr->block) 3651 list_del_init(&cqr->blocklist); 3652 cqr->block->base->discipline->free_cp( 3653 cqr, (struct request *) cqr->callback_data); 3654 } 3655 3656 /* 3657 * if requests remain then they are internal request 3658 * and go back to the device queue 3659 */ 3660 if (!list_empty(&freeze_queue)) { 3661 /* move freeze_queue to start of the ccw_queue */ 3662 spin_lock_irq(get_ccwdev_lock(cdev)); 3663 list_splice_tail(&freeze_queue, &device->ccw_queue); 3664 spin_unlock_irq(get_ccwdev_lock(cdev)); 3665 } 3666 dasd_put_device(device); 3667 return rc; 3668 } 3669 EXPORT_SYMBOL_GPL(dasd_generic_pm_freeze); 3670 3671 int dasd_generic_restore_device(struct ccw_device *cdev) 3672 { 3673 struct dasd_device *device = dasd_device_from_cdev(cdev); 3674 int rc = 0; 3675 3676 if (IS_ERR(device)) 3677 return PTR_ERR(device); 3678 3679 /* allow new IO again */ 3680 dasd_device_remove_stop_bits(device, 3681 (DASD_STOPPED_PM | DASD_UNRESUMED_PM)); 3682 3683 dasd_schedule_device_bh(device); 3684 3685 /* 3686 * call discipline restore function 3687 * if device is stopped do nothing e.g. for disconnected devices 3688 */ 3689 if (device->discipline->restore && !(device->stopped)) 3690 rc = device->discipline->restore(device); 3691 if (rc || device->stopped) 3692 /* 3693 * if the resume failed for the DASD we put it in 3694 * an UNRESUMED stop state 3695 */ 3696 device->stopped |= DASD_UNRESUMED_PM; 3697 3698 if (device->block) 3699 dasd_schedule_block_bh(device->block); 3700 3701 clear_bit(DASD_FLAG_SUSPENDED, &device->flags); 3702 dasd_put_device(device); 3703 return 0; 3704 } 3705 EXPORT_SYMBOL_GPL(dasd_generic_restore_device); 3706 3707 static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device, 3708 void *rdc_buffer, 3709 int rdc_buffer_size, 3710 int magic) 3711 { 3712 struct dasd_ccw_req *cqr; 3713 struct ccw1 *ccw; 3714 unsigned long *idaw; 3715 3716 cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device); 3717 3718 if (IS_ERR(cqr)) { 3719 /* internal error 13 - Allocating the RDC request failed*/ 3720 dev_err(&device->cdev->dev, 3721 "An error occurred in the DASD device driver, " 3722 "reason=%s\n", "13"); 3723 return cqr; 3724 } 3725 3726 ccw = cqr->cpaddr; 3727 ccw->cmd_code = CCW_CMD_RDC; 3728 if (idal_is_needed(rdc_buffer, rdc_buffer_size)) { 3729 idaw = (unsigned long *) (cqr->data); 3730 ccw->cda = (__u32)(addr_t) idaw; 3731 ccw->flags = CCW_FLAG_IDA; 3732 idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size); 3733 } else { 3734 ccw->cda = (__u32)(addr_t) rdc_buffer; 3735 ccw->flags = 0; 3736 } 3737 3738 ccw->count = rdc_buffer_size; 3739 cqr->startdev = device; 3740 cqr->memdev = device; 3741 cqr->expires = 10*HZ; 3742 cqr->retries = 256; 3743 cqr->buildclk = get_tod_clock(); 3744 cqr->status = DASD_CQR_FILLED; 3745 return cqr; 3746 } 3747 3748 3749 int dasd_generic_read_dev_chars(struct dasd_device *device, int magic, 3750 void *rdc_buffer, int rdc_buffer_size) 3751 { 3752 int ret; 3753 struct dasd_ccw_req *cqr; 3754 3755 cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size, 3756 magic); 3757 if (IS_ERR(cqr)) 3758 return PTR_ERR(cqr); 3759 3760 ret = dasd_sleep_on(cqr); 3761 dasd_sfree_request(cqr, cqr->memdev); 3762 return ret; 3763 } 3764 EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars); 3765 3766 /* 3767 * In command mode and transport mode we need to look for sense 3768 * data in different places. The sense data itself is allways 3769 * an array of 32 bytes, so we can unify the sense data access 3770 * for both modes. 3771 */ 3772 char *dasd_get_sense(struct irb *irb) 3773 { 3774 struct tsb *tsb = NULL; 3775 char *sense = NULL; 3776 3777 if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) { 3778 if (irb->scsw.tm.tcw) 3779 tsb = tcw_get_tsb((struct tcw *)(unsigned long) 3780 irb->scsw.tm.tcw); 3781 if (tsb && tsb->length == 64 && tsb->flags) 3782 switch (tsb->flags & 0x07) { 3783 case 1: /* tsa_iostat */ 3784 sense = tsb->tsa.iostat.sense; 3785 break; 3786 case 2: /* tsa_ddpc */ 3787 sense = tsb->tsa.ddpc.sense; 3788 break; 3789 default: 3790 /* currently we don't use interrogate data */ 3791 break; 3792 } 3793 } else if (irb->esw.esw0.erw.cons) { 3794 sense = irb->ecw; 3795 } 3796 return sense; 3797 } 3798 EXPORT_SYMBOL_GPL(dasd_get_sense); 3799 3800 void dasd_generic_shutdown(struct ccw_device *cdev) 3801 { 3802 struct dasd_device *device; 3803 3804 device = dasd_device_from_cdev(cdev); 3805 if (IS_ERR(device)) 3806 return; 3807 3808 if (device->block) 3809 dasd_schedule_block_bh(device->block); 3810 3811 dasd_schedule_device_bh(device); 3812 3813 wait_event(shutdown_waitq, _wait_for_empty_queues(device)); 3814 } 3815 EXPORT_SYMBOL_GPL(dasd_generic_shutdown); 3816 3817 static int __init dasd_init(void) 3818 { 3819 int rc; 3820 3821 init_waitqueue_head(&dasd_init_waitq); 3822 init_waitqueue_head(&dasd_flush_wq); 3823 init_waitqueue_head(&generic_waitq); 3824 init_waitqueue_head(&shutdown_waitq); 3825 3826 /* register 'common' DASD debug area, used for all DBF_XXX calls */ 3827 dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long)); 3828 if (dasd_debug_area == NULL) { 3829 rc = -ENOMEM; 3830 goto failed; 3831 } 3832 debug_register_view(dasd_debug_area, &debug_sprintf_view); 3833 debug_set_level(dasd_debug_area, DBF_WARNING); 3834 3835 DBF_EVENT(DBF_EMERG, "%s", "debug area created"); 3836 3837 dasd_diag_discipline_pointer = NULL; 3838 3839 dasd_statistics_createroot(); 3840 3841 rc = dasd_devmap_init(); 3842 if (rc) 3843 goto failed; 3844 rc = dasd_gendisk_init(); 3845 if (rc) 3846 goto failed; 3847 rc = dasd_parse(); 3848 if (rc) 3849 goto failed; 3850 rc = dasd_eer_init(); 3851 if (rc) 3852 goto failed; 3853 #ifdef CONFIG_PROC_FS 3854 rc = dasd_proc_init(); 3855 if (rc) 3856 goto failed; 3857 #endif 3858 3859 return 0; 3860 failed: 3861 pr_info("The DASD device driver could not be initialized\n"); 3862 dasd_exit(); 3863 return rc; 3864 } 3865 3866 module_init(dasd_init); 3867 module_exit(dasd_exit); 3868 3869 EXPORT_SYMBOL(dasd_debug_area); 3870 EXPORT_SYMBOL(dasd_diag_discipline_pointer); 3871 3872 EXPORT_SYMBOL(dasd_add_request_head); 3873 EXPORT_SYMBOL(dasd_add_request_tail); 3874 EXPORT_SYMBOL(dasd_cancel_req); 3875 EXPORT_SYMBOL(dasd_device_clear_timer); 3876 EXPORT_SYMBOL(dasd_block_clear_timer); 3877 EXPORT_SYMBOL(dasd_enable_device); 3878 EXPORT_SYMBOL(dasd_int_handler); 3879 EXPORT_SYMBOL(dasd_kfree_request); 3880 EXPORT_SYMBOL(dasd_kick_device); 3881 EXPORT_SYMBOL(dasd_kmalloc_request); 3882 EXPORT_SYMBOL(dasd_schedule_device_bh); 3883 EXPORT_SYMBOL(dasd_schedule_block_bh); 3884 EXPORT_SYMBOL(dasd_set_target_state); 3885 EXPORT_SYMBOL(dasd_device_set_timer); 3886 EXPORT_SYMBOL(dasd_block_set_timer); 3887 EXPORT_SYMBOL(dasd_sfree_request); 3888 EXPORT_SYMBOL(dasd_sleep_on); 3889 EXPORT_SYMBOL(dasd_sleep_on_immediatly); 3890 EXPORT_SYMBOL(dasd_sleep_on_interruptible); 3891 EXPORT_SYMBOL(dasd_smalloc_request); 3892 EXPORT_SYMBOL(dasd_start_IO); 3893 EXPORT_SYMBOL(dasd_term_IO); 3894 3895 EXPORT_SYMBOL_GPL(dasd_generic_probe); 3896 EXPORT_SYMBOL_GPL(dasd_generic_remove); 3897 EXPORT_SYMBOL_GPL(dasd_generic_notify); 3898 EXPORT_SYMBOL_GPL(dasd_generic_set_online); 3899 EXPORT_SYMBOL_GPL(dasd_generic_set_offline); 3900 EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change); 3901 EXPORT_SYMBOL_GPL(dasd_flush_device_queue); 3902 EXPORT_SYMBOL_GPL(dasd_alloc_block); 3903 EXPORT_SYMBOL_GPL(dasd_free_block); 3904