drivers/s390/block/dasd.c

   1 /*
   2  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   3  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
   4  *                  Carsten Otte <Cotte@de.ibm.com>
   5  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
   6  * Bugreports.to..: <Linux390@de.ibm.com>
   7  * Copyright IBM Corp. 1999, 2009
   8  */
   9
  10 #define KMSG_COMPONENT "dasd"
  11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  12
  13 #include <linux/kmod.h>
  14 #include <linux/init.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/ctype.h>
  17 #include <linux/major.h>
  18 #include <linux/slab.h>
  19 #include <linux/hdreg.h>
  20 #include <linux/async.h>
  21 #include <linux/mutex.h>
  22 #include <linux/debugfs.h>
  23 #include <linux/seq_file.h>
  24 #include <linux/vmalloc.h>
  25
  26 #include <asm/ccwdev.h>
  27 #include <asm/ebcdic.h>
  28 #include <asm/idals.h>
  29 #include <asm/itcw.h>
  30 #include <asm/diag.h>
  31
  32 /* This is ugly... */
  33 #define PRINTK_HEADER "dasd:"
  34
  35 #include "dasd_int.h"
  36 /*
  37  * SECTION: Constant definitions to be used within this file
  38  */
  39 #define DASD_CHANQ_MAX_SIZE 4
  40
  41 #define DASD_DIAG_MOD           "dasd_diag_mod"
  42
  43 /*
  44  * SECTION: exported variables of dasd.c
  45  */
  46 debug_info_t *dasd_debug_area;
  47 EXPORT_SYMBOL(dasd_debug_area);
  48 static struct dentry *dasd_debugfs_root_entry;
  49 struct dasd_discipline *dasd_diag_discipline_pointer;
  50 EXPORT_SYMBOL(dasd_diag_discipline_pointer);
  51 void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *);
  52
  53 MODULE_AUTHOR("Holger Smolinski <Holger.Smolinski@de.ibm.com>");
  54 MODULE_DESCRIPTION("Linux on S/390 DASD device driver,"
  55                    " Copyright IBM Corp. 2000");
  56 MODULE_SUPPORTED_DEVICE("dasd");
  57 MODULE_LICENSE("GPL");
  58
  59 /*
  60  * SECTION: prototypes for static functions of dasd.c
  61  */
  62 static int  dasd_alloc_queue(struct dasd_block *);
  63 static void dasd_setup_queue(struct dasd_block *);
  64 static void dasd_free_queue(struct dasd_block *);
  65 static void dasd_flush_request_queue(struct dasd_block *);
  66 static int dasd_flush_block_queue(struct dasd_block *);
  67 static void dasd_device_tasklet(struct dasd_device *);
  68 static void dasd_block_tasklet(struct dasd_block *);
  69 static void do_kick_device(struct work_struct *);
  70 static void do_restore_device(struct work_struct *);
  71 static void do_reload_device(struct work_struct *);
  72 static void do_requeue_requests(struct work_struct *);
  73 static void dasd_return_cqr_cb(struct dasd_ccw_req *, void *);
  74 static void dasd_device_timeout(unsigned long);
  75 static void dasd_block_timeout(unsigned long);
  76 static void __dasd_process_erp(struct dasd_device *, struct dasd_ccw_req *);
  77 static void dasd_profile_init(struct dasd_profile *, struct dentry *);
  78 static void dasd_profile_exit(struct dasd_profile *);
  79 static void dasd_hosts_init(struct dentry *, struct dasd_device *);
  80 static void dasd_hosts_exit(struct dasd_device *);
  81
  82 /*
  83  * SECTION: Operations on the device structure.
  84  */
  85 static wait_queue_head_t dasd_init_waitq;
  86 static wait_queue_head_t dasd_flush_wq;
  87 static wait_queue_head_t generic_waitq;
  88 static wait_queue_head_t shutdown_waitq;
  89
  90 /*
  91  * Allocate memory for a new device structure.
  92  */
  93 struct dasd_device *dasd_alloc_device(void)
  94 {
  95         struct dasd_device *device;
  96
  97         device = kzalloc(sizeof(struct dasd_device), GFP_ATOMIC);
  98         if (!device)
  99                 return ERR_PTR(-ENOMEM);
 100
 101         /* Get two pages for normal block device operations. */
 102         device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
 103         if (!device->ccw_mem) {
 104                 kfree(device);
 105                 return ERR_PTR(-ENOMEM);
 106         }
 107         /* Get one page for error recovery. */
 108         device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
 109         if (!device->erp_mem) {
 110                 free_pages((unsigned long) device->ccw_mem, 1);
 111                 kfree(device);
 112                 return ERR_PTR(-ENOMEM);
 113         }
 114
 115         dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
 116         dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
 117         spin_lock_init(&device->mem_lock);
 118         atomic_set(&device->tasklet_scheduled, 0);
 119         tasklet_init(&device->tasklet,
 120                      (void (*)(unsigned long)) dasd_device_tasklet,
 121                      (unsigned long) device);
 122         INIT_LIST_HEAD(&device->ccw_queue);
 123         init_timer(&device->timer);
 124         device->timer.function = dasd_device_timeout;
 125         device->timer.data = (unsigned long) device;
 126         INIT_WORK(&device->kick_work, do_kick_device);
 127         INIT_WORK(&device->restore_device, do_restore_device);
 128         INIT_WORK(&device->reload_device, do_reload_device);
 129         INIT_WORK(&device->requeue_requests, do_requeue_requests);
 130         device->state = DASD_STATE_NEW;
 131         device->target = DASD_STATE_NEW;
 132         mutex_init(&device->state_mutex);
 133         spin_lock_init(&device->profile.lock);
 134         return device;
 135 }
 136
 137 /*
 138  * Free memory of a device structure.
 139  */
 140 void dasd_free_device(struct dasd_device *device)
 141 {
 142         kfree(device->private);
 143         free_page((unsigned long) device->erp_mem);
 144         free_pages((unsigned long) device->ccw_mem, 1);
 145         kfree(device);
 146 }
 147
 148 /*
 149  * Allocate memory for a new device structure.
 150  */
 151 struct dasd_block *dasd_alloc_block(void)
 152 {
 153         struct dasd_block *block;
 154
 155         block = kzalloc(sizeof(*block), GFP_ATOMIC);
 156         if (!block)
 157                 return ERR_PTR(-ENOMEM);
 158         /* open_count = 0 means device online but not in use */
 159         atomic_set(&block->open_count, -1);
 160
 161         spin_lock_init(&block->request_queue_lock);
 162         atomic_set(&block->tasklet_scheduled, 0);
 163         tasklet_init(&block->tasklet,
 164                      (void (*)(unsigned long)) dasd_block_tasklet,
 165                      (unsigned long) block);
 166         INIT_LIST_HEAD(&block->ccw_queue);
 167         spin_lock_init(&block->queue_lock);
 168         init_timer(&block->timer);
 169         block->timer.function = dasd_block_timeout;
 170         block->timer.data = (unsigned long) block;
 171         spin_lock_init(&block->profile.lock);
 172
 173         return block;
 174 }
 175 EXPORT_SYMBOL_GPL(dasd_alloc_block);
 176
 177 /*
 178  * Free memory of a device structure.
 179  */
 180 void dasd_free_block(struct dasd_block *block)
 181 {
 182         kfree(block);
 183 }
 184 EXPORT_SYMBOL_GPL(dasd_free_block);
 185
 186 /*
 187  * Make a new device known to the system.
 188  */
 189 static int dasd_state_new_to_known(struct dasd_device *device)
 190 {
 191         int rc;
 192
 193         /*
 194          * As long as the device is not in state DASD_STATE_NEW we want to
 195          * keep the reference count > 0.
 196          */
 197         dasd_get_device(device);
 198
 199         if (device->block) {
 200                 rc = dasd_alloc_queue(device->block);
 201                 if (rc) {
 202                         dasd_put_device(device);
 203                         return rc;
 204                 }
 205         }
 206         device->state = DASD_STATE_KNOWN;
 207         return 0;
 208 }
 209
 210 /*
 211  * Let the system forget about a device.
 212  */
 213 static int dasd_state_known_to_new(struct dasd_device *device)
 214 {
 215         /* Disable extended error reporting for this device. */
 216         dasd_eer_disable(device);
 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         dasd_hosts_init(device->debugfs_dentry, device);
 265
 266         /* register 'device' debug area, used for all DBF_DEV_XXX calls */
 267         device->debug_area = debug_register(dev_name(&device->cdev->dev), 4, 1,
 268                                             8 * sizeof(long));
 269         debug_register_view(device->debug_area, &debug_sprintf_view);
 270         debug_set_level(device->debug_area, DBF_WARNING);
 271         DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
 272
 273         device->state = DASD_STATE_BASIC;
 274
 275         return rc;
 276 }
 277
 278 /*
 279  * Release the irq line for the device. Terminate any running i/o.
 280  */
 281 static int dasd_state_basic_to_known(struct dasd_device *device)
 282 {
 283         int rc;
 284
 285         if (device->discipline->basic_to_known) {
 286                 rc = device->discipline->basic_to_known(device);
 287                 if (rc)
 288                         return rc;
 289         }
 290
 291         if (device->block) {
 292                 dasd_profile_exit(&device->block->profile);
 293                 debugfs_remove(device->block->debugfs_dentry);
 294                 dasd_gendisk_free(device->block);
 295                 dasd_block_clear_timer(device->block);
 296         }
 297         rc = dasd_flush_device_queue(device);
 298         if (rc)
 299                 return rc;
 300         dasd_device_clear_timer(device);
 301         dasd_profile_exit(&device->profile);
 302         dasd_hosts_exit(device);
 303         debugfs_remove(device->debugfs_dentry);
 304         DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
 305         if (device->debug_area != NULL) {
 306                 debug_unregister(device->debug_area);
 307                 device->debug_area = NULL;
 308         }
 309         device->state = DASD_STATE_KNOWN;
 310         return 0;
 311 }
 312
 313 /*
 314  * Do the initial analysis. The do_analysis function may return
 315  * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC
 316  * until the discipline decides to continue the startup sequence
 317  * by calling the function dasd_change_state. The eckd disciplines
 318  * uses this to start a ccw that detects the format. The completion
 319  * interrupt for this detection ccw uses the kernel event daemon to
 320  * trigger the call to dasd_change_state. All this is done in the
 321  * discipline code, see dasd_eckd.c.
 322  * After the analysis ccw is done (do_analysis returned 0) the block
 323  * device is setup.
 324  * In case the analysis returns an error, the device setup is stopped
 325  * (a fake disk was already added to allow formatting).
 326  */
 327 static int dasd_state_basic_to_ready(struct dasd_device *device)
 328 {
 329         int rc;
 330         struct dasd_block *block;
 331         struct gendisk *disk;
 332
 333         rc = 0;
 334         block = device->block;
 335         /* make disk known with correct capacity */
 336         if (block) {
 337                 if (block->base->discipline->do_analysis != NULL)
 338                         rc = block->base->discipline->do_analysis(block);
 339                 if (rc) {
 340                         if (rc != -EAGAIN) {
 341                                 device->state = DASD_STATE_UNFMT;
 342                                 disk = device->block->gdp;
 343                                 kobject_uevent(&disk_to_dev(disk)->kobj,
 344                                                KOBJ_CHANGE);
 345                                 goto out;
 346                         }
 347                         return rc;
 348                 }
 349                 dasd_setup_queue(block);
 350                 set_capacity(block->gdp,
 351                              block->blocks << block->s2b_shift);
 352                 device->state = DASD_STATE_READY;
 353                 rc = dasd_scan_partitions(block);
 354                 if (rc) {
 355                         device->state = DASD_STATE_BASIC;
 356                         return rc;
 357                 }
 358         } else {
 359                 device->state = DASD_STATE_READY;
 360         }
 361 out:
 362         if (device->discipline->basic_to_ready)
 363                 rc = device->discipline->basic_to_ready(device);
 364         return rc;
 365 }
 366
 367 static inline
 368 int _wait_for_empty_queues(struct dasd_device *device)
 369 {
 370         if (device->block)
 371                 return list_empty(&device->ccw_queue) &&
 372                         list_empty(&device->block->ccw_queue);
 373         else
 374                 return list_empty(&device->ccw_queue);
 375 }
 376
 377 /*
 378  * Remove device from block device layer. Destroy dirty buffers.
 379  * Forget format information. Check if the target level is basic
 380  * and if it is create fake disk for formatting.
 381  */
 382 static int dasd_state_ready_to_basic(struct dasd_device *device)
 383 {
 384         int rc;
 385
 386         device->state = DASD_STATE_BASIC;
 387         if (device->block) {
 388                 struct dasd_block *block = device->block;
 389                 rc = dasd_flush_block_queue(block);
 390                 if (rc) {
 391                         device->state = DASD_STATE_READY;
 392                         return rc;
 393                 }
 394                 dasd_flush_request_queue(block);
 395                 dasd_destroy_partitions(block);
 396                 block->blocks = 0;
 397                 block->bp_block = 0;
 398                 block->s2b_shift = 0;
 399         }
 400         return 0;
 401 }
 402
 403 /*
 404  * Back to basic.
 405  */
 406 static int dasd_state_unfmt_to_basic(struct dasd_device *device)
 407 {
 408         device->state = DASD_STATE_BASIC;
 409         return 0;
 410 }
 411
 412 /*
 413  * Make the device online and schedule the bottom half to start
 414  * the requeueing of requests from the linux request queue to the
 415  * ccw queue.
 416  */
 417 static int
 418 dasd_state_ready_to_online(struct dasd_device * device)
 419 {
 420         struct gendisk *disk;
 421         struct disk_part_iter piter;
 422         struct hd_struct *part;
 423
 424         device->state = DASD_STATE_ONLINE;
 425         if (device->block) {
 426                 dasd_schedule_block_bh(device->block);
 427                 if ((device->features & DASD_FEATURE_USERAW)) {
 428                         disk = device->block->gdp;
 429                         kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
 430                         return 0;
 431                 }
 432                 disk = device->block->bdev->bd_disk;
 433                 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
 434                 while ((part = disk_part_iter_next(&piter)))
 435                         kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
 436                 disk_part_iter_exit(&piter);
 437         }
 438         return 0;
 439 }
 440
 441 /*
 442  * Stop the requeueing of requests again.
 443  */
 444 static int dasd_state_online_to_ready(struct dasd_device *device)
 445 {
 446         int rc;
 447         struct gendisk *disk;
 448         struct disk_part_iter piter;
 449         struct hd_struct *part;
 450
 451         if (device->discipline->online_to_ready) {
 452                 rc = device->discipline->online_to_ready(device);
 453                 if (rc)
 454                         return rc;
 455         }
 456
 457         device->state = DASD_STATE_READY;
 458         if (device->block && !(device->features & DASD_FEATURE_USERAW)) {
 459                 disk = device->block->bdev->bd_disk;
 460                 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
 461                 while ((part = disk_part_iter_next(&piter)))
 462                         kobject_uevent(&part_to_dev(part)->kobj, KOBJ_CHANGE);
 463                 disk_part_iter_exit(&piter);
 464         }
 465         return 0;
 466 }
 467
 468 /*
 469  * Device startup state changes.
 470  */
 471 static int dasd_increase_state(struct dasd_device *device)
 472 {
 473         int rc;
 474
 475         rc = 0;
 476         if (device->state == DASD_STATE_NEW &&
 477             device->target >= DASD_STATE_KNOWN)
 478                 rc = dasd_state_new_to_known(device);
 479
 480         if (!rc &&
 481             device->state == DASD_STATE_KNOWN &&
 482             device->target >= DASD_STATE_BASIC)
 483                 rc = dasd_state_known_to_basic(device);
 484
 485         if (!rc &&
 486             device->state == DASD_STATE_BASIC &&
 487             device->target >= DASD_STATE_READY)
 488                 rc = dasd_state_basic_to_ready(device);
 489
 490         if (!rc &&
 491             device->state == DASD_STATE_UNFMT &&
 492             device->target > DASD_STATE_UNFMT)
 493                 rc = -EPERM;
 494
 495         if (!rc &&
 496             device->state == DASD_STATE_READY &&
 497             device->target >= DASD_STATE_ONLINE)
 498                 rc = dasd_state_ready_to_online(device);
 499
 500         return rc;
 501 }
 502
 503 /*
 504  * Device shutdown state changes.
 505  */
 506 static int dasd_decrease_state(struct dasd_device *device)
 507 {
 508         int rc;
 509
 510         rc = 0;
 511         if (device->state == DASD_STATE_ONLINE &&
 512             device->target <= DASD_STATE_READY)
 513                 rc = dasd_state_online_to_ready(device);
 514
 515         if (!rc &&
 516             device->state == DASD_STATE_READY &&
 517             device->target <= DASD_STATE_BASIC)
 518                 rc = dasd_state_ready_to_basic(device);
 519
 520         if (!rc &&
 521             device->state == DASD_STATE_UNFMT &&
 522             device->target <= DASD_STATE_BASIC)
 523                 rc = dasd_state_unfmt_to_basic(device);
 524
 525         if (!rc &&
 526             device->state == DASD_STATE_BASIC &&
 527             device->target <= DASD_STATE_KNOWN)
 528                 rc = dasd_state_basic_to_known(device);
 529
 530         if (!rc &&
 531             device->state == DASD_STATE_KNOWN &&
 532             device->target <= DASD_STATE_NEW)
 533                 rc = dasd_state_known_to_new(device);
 534
 535         return rc;
 536 }
 537
 538 /*
 539  * This is the main startup/shutdown routine.
 540  */
 541 static void dasd_change_state(struct dasd_device *device)
 542 {
 543         int rc;
 544
 545         if (device->state == device->target)
 546                 /* Already where we want to go today... */
 547                 return;
 548         if (device->state < device->target)
 549                 rc = dasd_increase_state(device);
 550         else
 551                 rc = dasd_decrease_state(device);
 552         if (rc == -EAGAIN)
 553                 return;
 554         if (rc)
 555                 device->target = device->state;
 556
 557         /* let user-space know that the device status changed */
 558         kobject_uevent(&device->cdev->dev.kobj, KOBJ_CHANGE);
 559
 560         if (device->state == device->target)
 561                 wake_up(&dasd_init_waitq);
 562 }
 563
 564 /*
 565  * Kick starter for devices that did not complete the startup/shutdown
 566  * procedure or were sleeping because of a pending state.
 567  * dasd_kick_device will schedule a call do do_kick_device to the kernel
 568  * event daemon.
 569  */
 570 static void do_kick_device(struct work_struct *work)
 571 {
 572         struct dasd_device *device = container_of(work, struct dasd_device, kick_work);
 573         mutex_lock(&device->state_mutex);
 574         dasd_change_state(device);
 575         mutex_unlock(&device->state_mutex);
 576         dasd_schedule_device_bh(device);
 577         dasd_put_device(device);
 578 }
 579
 580 void dasd_kick_device(struct dasd_device *device)
 581 {
 582         dasd_get_device(device);
 583         /* queue call to dasd_kick_device to the kernel event daemon. */
 584         if (!schedule_work(&device->kick_work))
 585                 dasd_put_device(device);
 586 }
 587 EXPORT_SYMBOL(dasd_kick_device);
 588
 589 /*
 590  * dasd_reload_device will schedule a call do do_reload_device to the kernel
 591  * event daemon.
 592  */
 593 static void do_reload_device(struct work_struct *work)
 594 {
 595         struct dasd_device *device = container_of(work, struct dasd_device,
 596                                                   reload_device);
 597         device->discipline->reload(device);
 598         dasd_put_device(device);
 599 }
 600
 601 void dasd_reload_device(struct dasd_device *device)
 602 {
 603         dasd_get_device(device);
 604         /* queue call to dasd_reload_device to the kernel event daemon. */
 605         if (!schedule_work(&device->reload_device))
 606                 dasd_put_device(device);
 607 }
 608 EXPORT_SYMBOL(dasd_reload_device);
 609
 610 /*
 611  * dasd_restore_device will schedule a call do do_restore_device to the kernel
 612  * event daemon.
 613  */
 614 static void do_restore_device(struct work_struct *work)
 615 {
 616         struct dasd_device *device = container_of(work, struct dasd_device,
 617                                                   restore_device);
 618         device->cdev->drv->restore(device->cdev);
 619         dasd_put_device(device);
 620 }
 621
 622 void dasd_restore_device(struct dasd_device *device)
 623 {
 624         dasd_get_device(device);
 625         /* queue call to dasd_restore_device to the kernel event daemon. */
 626         if (!schedule_work(&device->restore_device))
 627                 dasd_put_device(device);
 628 }
 629
 630 /*
 631  * Set the target state for a device and starts the state change.
 632  */
 633 void dasd_set_target_state(struct dasd_device *device, int target)
 634 {
 635         dasd_get_device(device);
 636         mutex_lock(&device->state_mutex);
 637         /* If we are in probeonly mode stop at DASD_STATE_READY. */
 638         if (dasd_probeonly && target > DASD_STATE_READY)
 639                 target = DASD_STATE_READY;
 640         if (device->target != target) {
 641                 if (device->state == target)
 642                         wake_up(&dasd_init_waitq);
 643                 device->target = target;
 644         }
 645         if (device->state != device->target)
 646                 dasd_change_state(device);
 647         mutex_unlock(&device->state_mutex);
 648         dasd_put_device(device);
 649 }
 650 EXPORT_SYMBOL(dasd_set_target_state);
 651
 652 /*
 653  * Enable devices with device numbers in [from..to].
 654  */
 655 static inline int _wait_for_device(struct dasd_device *device)
 656 {
 657         return (device->state == device->target);
 658 }
 659
 660 void dasd_enable_device(struct dasd_device *device)
 661 {
 662         dasd_set_target_state(device, DASD_STATE_ONLINE);
 663         if (device->state <= DASD_STATE_KNOWN)
 664                 /* No discipline for device found. */
 665                 dasd_set_target_state(device, DASD_STATE_NEW);
 666         /* Now wait for the devices to come up. */
 667         wait_event(dasd_init_waitq, _wait_for_device(device));
 668
 669         dasd_reload_device(device);
 670         if (device->discipline->kick_validate)
 671                 device->discipline->kick_validate(device);
 672 }
 673 EXPORT_SYMBOL(dasd_enable_device);
 674
 675 /*
 676  * SECTION: device operation (interrupt handler, start i/o, term i/o ...)
 677  */
 678
 679 unsigned int dasd_global_profile_level = DASD_PROFILE_OFF;
 680
 681 #ifdef CONFIG_DASD_PROFILE
 682 struct dasd_profile dasd_global_profile = {
 683         .lock = __SPIN_LOCK_UNLOCKED(dasd_global_profile.lock),
 684 };
 685 static struct dentry *dasd_debugfs_global_entry;
 686
 687 /*
 688  * Add profiling information for cqr before execution.
 689  */
 690 static void dasd_profile_start(struct dasd_block *block,
 691                                struct dasd_ccw_req *cqr,
 692                                struct request *req)
 693 {
 694         struct list_head *l;
 695         unsigned int counter;
 696         struct dasd_device *device;
 697
 698         /* count the length of the chanq for statistics */
 699         counter = 0;
 700         if (dasd_global_profile_level || block->profile.data)
 701                 list_for_each(l, &block->ccw_queue)
 702                         if (++counter >= 31)
 703                                 break;
 704
 705         spin_lock(&dasd_global_profile.lock);
 706         if (dasd_global_profile.data) {
 707                 dasd_global_profile.data->dasd_io_nr_req[counter]++;
 708                 if (rq_data_dir(req) == READ)
 709                         dasd_global_profile.data->dasd_read_nr_req[counter]++;
 710         }
 711         spin_unlock(&dasd_global_profile.lock);
 712
 713         spin_lock(&block->profile.lock);
 714         if (block->profile.data) {
 715                 block->profile.data->dasd_io_nr_req[counter]++;
 716                 if (rq_data_dir(req) == READ)
 717                         block->profile.data->dasd_read_nr_req[counter]++;
 718         }
 719         spin_unlock(&block->profile.lock);
 720
 721         /*
 722          * We count the request for the start device, even though it may run on
 723          * some other device due to error recovery. This way we make sure that
 724          * we count each request only once.
 725          */
 726         device = cqr->startdev;
 727         if (device->profile.data) {
 728                 counter = 1; /* request is not yet queued on the start device */
 729                 list_for_each(l, &device->ccw_queue)
 730                         if (++counter >= 31)
 731                                 break;
 732         }
 733         spin_lock(&device->profile.lock);
 734         if (device->profile.data) {
 735                 device->profile.data->dasd_io_nr_req[counter]++;
 736                 if (rq_data_dir(req) == READ)
 737                         device->profile.data->dasd_read_nr_req[counter]++;
 738         }
 739         spin_unlock(&device->profile.lock);
 740 }
 741
 742 /*
 743  * Add profiling information for cqr after execution.
 744  */
 745
 746 #define dasd_profile_counter(value, index)                         \
 747 {                                                                  \
 748         for (index = 0; index < 31 && value >> (2+index); index++) \
 749                 ;                                                  \
 750 }
 751
 752 static void dasd_profile_end_add_data(struct dasd_profile_info *data,
 753                                       int is_alias,
 754                                       int is_tpm,
 755                                       int is_read,
 756                                       long sectors,
 757                                       int sectors_ind,
 758                                       int tottime_ind,
 759                                       int tottimeps_ind,
 760                                       int strtime_ind,
 761                                       int irqtime_ind,
 762                                       int irqtimeps_ind,
 763                                       int endtime_ind)
 764 {
 765         /* in case of an overflow, reset the whole profile */
 766         if (data->dasd_io_reqs == UINT_MAX) {
 767                         memset(data, 0, sizeof(*data));
 768                         getnstimeofday(&data->starttod);
 769         }
 770         data->dasd_io_reqs++;
 771         data->dasd_io_sects += sectors;
 772         if (is_alias)
 773                 data->dasd_io_alias++;
 774         if (is_tpm)
 775                 data->dasd_io_tpm++;
 776
 777         data->dasd_io_secs[sectors_ind]++;
 778         data->dasd_io_times[tottime_ind]++;
 779         data->dasd_io_timps[tottimeps_ind]++;
 780         data->dasd_io_time1[strtime_ind]++;
 781         data->dasd_io_time2[irqtime_ind]++;
 782         data->dasd_io_time2ps[irqtimeps_ind]++;
 783         data->dasd_io_time3[endtime_ind]++;
 784
 785         if (is_read) {
 786                 data->dasd_read_reqs++;
 787                 data->dasd_read_sects += sectors;
 788                 if (is_alias)
 789                         data->dasd_read_alias++;
 790                 if (is_tpm)
 791                         data->dasd_read_tpm++;
 792                 data->dasd_read_secs[sectors_ind]++;
 793                 data->dasd_read_times[tottime_ind]++;
 794                 data->dasd_read_time1[strtime_ind]++;
 795                 data->dasd_read_time2[irqtime_ind]++;
 796                 data->dasd_read_time3[endtime_ind]++;
 797         }
 798 }
 799
 800 static void dasd_profile_end(struct dasd_block *block,
 801                              struct dasd_ccw_req *cqr,
 802                              struct request *req)
 803 {
 804         long strtime, irqtime, endtime, tottime;        /* in microseconds */
 805         long tottimeps, sectors;
 806         struct dasd_device *device;
 807         int sectors_ind, tottime_ind, tottimeps_ind, strtime_ind;
 808         int irqtime_ind, irqtimeps_ind, endtime_ind;
 809
 810         device = cqr->startdev;
 811         if (!(dasd_global_profile_level ||
 812               block->profile.data ||
 813               device->profile.data))
 814                 return;
 815
 816         sectors = blk_rq_sectors(req);
 817         if (!cqr->buildclk || !cqr->startclk ||
 818             !cqr->stopclk || !cqr->endclk ||
 819             !sectors)
 820                 return;
 821
 822         strtime = ((cqr->startclk - cqr->buildclk) >> 12);
 823         irqtime = ((cqr->stopclk - cqr->startclk) >> 12);
 824         endtime = ((cqr->endclk - cqr->stopclk) >> 12);
 825         tottime = ((cqr->endclk - cqr->buildclk) >> 12);
 826         tottimeps = tottime / sectors;
 827
 828         dasd_profile_counter(sectors, sectors_ind);
 829         dasd_profile_counter(tottime, tottime_ind);
 830         dasd_profile_counter(tottimeps, tottimeps_ind);
 831         dasd_profile_counter(strtime, strtime_ind);
 832         dasd_profile_counter(irqtime, irqtime_ind);
 833         dasd_profile_counter(irqtime / sectors, irqtimeps_ind);
 834         dasd_profile_counter(endtime, endtime_ind);
 835
 836         spin_lock(&dasd_global_profile.lock);
 837         if (dasd_global_profile.data) {
 838                 dasd_profile_end_add_data(dasd_global_profile.data,
 839                                           cqr->startdev != block->base,
 840                                           cqr->cpmode == 1,
 841                                           rq_data_dir(req) == READ,
 842                                           sectors, sectors_ind, tottime_ind,
 843                                           tottimeps_ind, strtime_ind,
 844                                           irqtime_ind, irqtimeps_ind,
 845                                           endtime_ind);
 846         }
 847         spin_unlock(&dasd_global_profile.lock);
 848
 849         spin_lock(&block->profile.lock);
 850         if (block->profile.data)
 851                 dasd_profile_end_add_data(block->profile.data,
 852                                           cqr->startdev != block->base,
 853                                           cqr->cpmode == 1,
 854                                           rq_data_dir(req) == READ,
 855                                           sectors, sectors_ind, tottime_ind,
 856                                           tottimeps_ind, strtime_ind,
 857                                           irqtime_ind, irqtimeps_ind,
 858                                           endtime_ind);
 859         spin_unlock(&block->profile.lock);
 860
 861         spin_lock(&device->profile.lock);
 862         if (device->profile.data)
 863                 dasd_profile_end_add_data(device->profile.data,
 864                                           cqr->startdev != block->base,
 865                                           cqr->cpmode == 1,
 866                                           rq_data_dir(req) == READ,
 867                                           sectors, sectors_ind, tottime_ind,
 868                                           tottimeps_ind, strtime_ind,
 869                                           irqtime_ind, irqtimeps_ind,
 870                                           endtime_ind);
 871         spin_unlock(&device->profile.lock);
 872 }
 873
 874 void dasd_profile_reset(struct dasd_profile *profile)
 875 {
 876         struct dasd_profile_info *data;
 877
 878         spin_lock_bh(&profile->lock);
 879         data = profile->data;
 880         if (!data) {
 881                 spin_unlock_bh(&profile->lock);
 882                 return;
 883         }
 884         memset(data, 0, sizeof(*data));
 885         getnstimeofday(&data->starttod);
 886         spin_unlock_bh(&profile->lock);
 887 }
 888
 889 int dasd_profile_on(struct dasd_profile *profile)
 890 {
 891         struct dasd_profile_info *data;
 892
 893         data = kzalloc(sizeof(*data), GFP_KERNEL);
 894         if (!data)
 895                 return -ENOMEM;
 896         spin_lock_bh(&profile->lock);
 897         if (profile->data) {
 898                 spin_unlock_bh(&profile->lock);
 899                 kfree(data);
 900                 return 0;
 901         }
 902         getnstimeofday(&data->starttod);
 903         profile->data = data;
 904         spin_unlock_bh(&profile->lock);
 905         return 0;
 906 }
 907
 908 void dasd_profile_off(struct dasd_profile *profile)
 909 {
 910         spin_lock_bh(&profile->lock);
 911         kfree(profile->data);
 912         profile->data = NULL;
 913         spin_unlock_bh(&profile->lock);
 914 }
 915
 916 char *dasd_get_user_string(const char __user *user_buf, size_t user_len)
 917 {
 918         char *buffer;
 919
 920         buffer = vmalloc(user_len + 1);
 921         if (buffer == NULL)
 922                 return ERR_PTR(-ENOMEM);
 923         if (copy_from_user(buffer, user_buf, user_len) != 0) {
 924                 vfree(buffer);
 925                 return ERR_PTR(-EFAULT);
 926         }
 927         /* got the string, now strip linefeed. */
 928         if (buffer[user_len - 1] == '\n')
 929                 buffer[user_len - 1] = 0;
 930         else
 931                 buffer[user_len] = 0;
 932         return buffer;
 933 }
 934
 935 static ssize_t dasd_stats_write(struct file *file,
 936                                 const char __user *user_buf,
 937                                 size_t user_len, loff_t *pos)
 938 {
 939         char *buffer, *str;
 940         int rc;
 941         struct seq_file *m = (struct seq_file *)file->private_data;
 942         struct dasd_profile *prof = m->private;
 943
 944         if (user_len > 65536)
 945                 user_len = 65536;
 946         buffer = dasd_get_user_string(user_buf, user_len);
 947         if (IS_ERR(buffer))
 948                 return PTR_ERR(buffer);
 949
 950         str = skip_spaces(buffer);
 951         rc = user_len;
 952         if (strncmp(str, "reset", 5) == 0) {
 953                 dasd_profile_reset(prof);
 954         } else if (strncmp(str, "on", 2) == 0) {
 955                 rc = dasd_profile_on(prof);
 956                 if (rc)
 957                         goto out;
 958                 rc = user_len;
 959                 if (prof == &dasd_global_profile) {
 960                         dasd_profile_reset(prof);
 961                         dasd_global_profile_level = DASD_PROFILE_GLOBAL_ONLY;
 962                 }
 963         } else if (strncmp(str, "off", 3) == 0) {
 964                 if (prof == &dasd_global_profile)
 965                         dasd_global_profile_level = DASD_PROFILE_OFF;
 966                 dasd_profile_off(prof);
 967         } else
 968                 rc = -EINVAL;
 969 out:
 970         vfree(buffer);
 971         return rc;
 972 }
 973
 974 static void dasd_stats_array(struct seq_file *m, unsigned int *array)
 975 {
 976         int i;
 977
 978         for (i = 0; i < 32; i++)
 979                 seq_printf(m, "%u ", array[i]);
 980         seq_putc(m, '\n');
 981 }
 982
 983 static void dasd_stats_seq_print(struct seq_file *m,
 984                                  struct dasd_profile_info *data)
 985 {
 986         seq_printf(m, "start_time %ld.%09ld\n",
 987                    data->starttod.tv_sec, data->starttod.tv_nsec);
 988         seq_printf(m, "total_requests %u\n", data->dasd_io_reqs);
 989         seq_printf(m, "total_sectors %u\n", data->dasd_io_sects);
 990         seq_printf(m, "total_pav %u\n", data->dasd_io_alias);
 991         seq_printf(m, "total_hpf %u\n", data->dasd_io_tpm);
 992         seq_puts(m, "histogram_sectors ");
 993         dasd_stats_array(m, data->dasd_io_secs);
 994         seq_puts(m, "histogram_io_times ");
 995         dasd_stats_array(m, data->dasd_io_times);
 996         seq_puts(m, "histogram_io_times_weighted ");
 997         dasd_stats_array(m, data->dasd_io_timps);
 998         seq_puts(m, "histogram_time_build_to_ssch ");
 999         dasd_stats_array(m, data->dasd_io_time1);
1000         seq_puts(m, "histogram_time_ssch_to_irq ");
1001         dasd_stats_array(m, data->dasd_io_time2);
1002         seq_puts(m, "histogram_time_ssch_to_irq_weighted ");
1003         dasd_stats_array(m, data->dasd_io_time2ps);
1004         seq_puts(m, "histogram_time_irq_to_end ");
1005         dasd_stats_array(m, data->dasd_io_time3);
1006         seq_puts(m, "histogram_ccw_queue_length ");
1007         dasd_stats_array(m, data->dasd_io_nr_req);
1008         seq_printf(m, "total_read_requests %u\n", data->dasd_read_reqs);
1009         seq_printf(m, "total_read_sectors %u\n", data->dasd_read_sects);
1010         seq_printf(m, "total_read_pav %u\n", data->dasd_read_alias);
1011         seq_printf(m, "total_read_hpf %u\n", data->dasd_read_tpm);
1012         seq_puts(m, "histogram_read_sectors ");
1013         dasd_stats_array(m, data->dasd_read_secs);
1014         seq_puts(m, "histogram_read_times ");
1015         dasd_stats_array(m, data->dasd_read_times);
1016         seq_puts(m, "histogram_read_time_build_to_ssch ");
1017         dasd_stats_array(m, data->dasd_read_time1);
1018         seq_puts(m, "histogram_read_time_ssch_to_irq ");
1019         dasd_stats_array(m, data->dasd_read_time2);
1020         seq_puts(m, "histogram_read_time_irq_to_end ");
1021         dasd_stats_array(m, data->dasd_read_time3);
1022         seq_puts(m, "histogram_read_ccw_queue_length ");
1023         dasd_stats_array(m, data->dasd_read_nr_req);
1024 }
1025
1026 static int dasd_stats_show(struct seq_file *m, void *v)
1027 {
1028         struct dasd_profile *profile;
1029         struct dasd_profile_info *data;
1030
1031         profile = m->private;
1032         spin_lock_bh(&profile->lock);
1033         data = profile->data;
1034         if (!data) {
1035                 spin_unlock_bh(&profile->lock);
1036                 seq_puts(m, "disabled\n");
1037                 return 0;
1038         }
1039         dasd_stats_seq_print(m, data);
1040         spin_unlock_bh(&profile->lock);
1041         return 0;
1042 }
1043
1044 static int dasd_stats_open(struct inode *inode, struct file *file)
1045 {
1046         struct dasd_profile *profile = inode->i_private;
1047         return single_open(file, dasd_stats_show, profile);
1048 }
1049
1050 static const struct file_operations dasd_stats_raw_fops = {
1051         .owner          = THIS_MODULE,
1052         .open           = dasd_stats_open,
1053         .read           = seq_read,
1054         .llseek         = seq_lseek,
1055         .release        = single_release,
1056         .write          = dasd_stats_write,
1057 };
1058
1059 static void dasd_profile_init(struct dasd_profile *profile,
1060                               struct dentry *base_dentry)
1061 {
1062         umode_t mode;
1063         struct dentry *pde;
1064
1065         if (!base_dentry)
1066                 return;
1067         profile->dentry = NULL;
1068         profile->data = NULL;
1069         mode = (S_IRUSR | S_IWUSR | S_IFREG);
1070         pde = debugfs_create_file("statistics", mode, base_dentry,
1071                                   profile, &dasd_stats_raw_fops);
1072         if (pde && !IS_ERR(pde))
1073                 profile->dentry = pde;
1074         return;
1075 }
1076
1077 static void dasd_profile_exit(struct dasd_profile *profile)
1078 {
1079         dasd_profile_off(profile);
1080         debugfs_remove(profile->dentry);
1081         profile->dentry = NULL;
1082 }
1083
1084 static void dasd_statistics_removeroot(void)
1085 {
1086         dasd_global_profile_level = DASD_PROFILE_OFF;
1087         dasd_profile_exit(&dasd_global_profile);
1088         debugfs_remove(dasd_debugfs_global_entry);
1089         debugfs_remove(dasd_debugfs_root_entry);
1090 }
1091
1092 static void dasd_statistics_createroot(void)
1093 {
1094         struct dentry *pde;
1095
1096         dasd_debugfs_root_entry = NULL;
1097         pde = debugfs_create_dir("dasd", NULL);
1098         if (!pde || IS_ERR(pde))
1099                 goto error;
1100         dasd_debugfs_root_entry = pde;
1101         pde = debugfs_create_dir("global", dasd_debugfs_root_entry);
1102         if (!pde || IS_ERR(pde))
1103                 goto error;
1104         dasd_debugfs_global_entry = pde;
1105         dasd_profile_init(&dasd_global_profile, dasd_debugfs_global_entry);
1106         return;
1107
1108 error:
1109         DBF_EVENT(DBF_ERR, "%s",
1110                   "Creation of the dasd debugfs interface failed");
1111         dasd_statistics_removeroot();
1112         return;
1113 }
1114
1115 #else
1116 #define dasd_profile_start(block, cqr, req) do {} while (0)
1117 #define dasd_profile_end(block, cqr, req) do {} while (0)
1118
1119 static void dasd_statistics_createroot(void)
1120 {
1121         return;
1122 }
1123
1124 static void dasd_statistics_removeroot(void)
1125 {
1126         return;
1127 }
1128
1129 int dasd_stats_generic_show(struct seq_file *m, void *v)
1130 {
1131         seq_puts(m, "Statistics are not activated in this kernel\n");
1132         return 0;
1133 }
1134
1135 static void dasd_profile_init(struct dasd_profile *profile,
1136                               struct dentry *base_dentry)
1137 {
1138         return;
1139 }
1140
1141 static void dasd_profile_exit(struct dasd_profile *profile)
1142 {
1143         return;
1144 }
1145
1146 int dasd_profile_on(struct dasd_profile *profile)
1147 {
1148         return 0;
1149 }
1150
1151 #endif                          /* CONFIG_DASD_PROFILE */
1152
1153 static int dasd_hosts_show(struct seq_file *m, void *v)
1154 {
1155         struct dasd_device *device;
1156         int rc = -EOPNOTSUPP;
1157
1158         device = m->private;
1159         dasd_get_device(device);
1160
1161         if (device->discipline->hosts_print)
1162                 rc = device->discipline->hosts_print(device, m);
1163
1164         dasd_put_device(device);
1165         return rc;
1166 }
1167
1168 static int dasd_hosts_open(struct inode *inode, struct file *file)
1169 {
1170         struct dasd_device *device = inode->i_private;
1171
1172         return single_open(file, dasd_hosts_show, device);
1173 }
1174
1175 static const struct file_operations dasd_hosts_fops = {
1176         .owner          = THIS_MODULE,
1177         .open           = dasd_hosts_open,
1178         .read           = seq_read,
1179         .llseek         = seq_lseek,
1180         .release        = single_release,
1181 };
1182
1183 static void dasd_hosts_exit(struct dasd_device *device)
1184 {
1185         debugfs_remove(device->hosts_dentry);
1186         device->hosts_dentry = NULL;
1187 }
1188
1189 static void dasd_hosts_init(struct dentry *base_dentry,
1190                             struct dasd_device *device)
1191 {
1192         struct dentry *pde;
1193         umode_t mode;
1194
1195         if (!base_dentry)
1196                 return;
1197
1198         mode = S_IRUSR | S_IFREG;
1199         pde = debugfs_create_file("host_access_list", mode, base_dentry,
1200                                   device, &dasd_hosts_fops);
1201         if (pde && !IS_ERR(pde))
1202                 device->hosts_dentry = pde;
1203 }
1204
1205 /*
1206  * Allocate memory for a channel program with 'cplength' channel
1207  * command words and 'datasize' additional space. There are two
1208  * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed
1209  * memory and 2) dasd_smalloc_request uses the static ccw memory
1210  * that gets allocated for each device.
1211  */
1212 struct dasd_ccw_req *dasd_kmalloc_request(int magic, int cplength,
1213                                           int datasize,
1214                                           struct dasd_device *device)
1215 {
1216         struct dasd_ccw_req *cqr;
1217
1218         /* Sanity checks */
1219         BUG_ON(datasize > PAGE_SIZE ||
1220              (cplength*sizeof(struct ccw1)) > PAGE_SIZE);
1221
1222         cqr = kzalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
1223         if (cqr == NULL)
1224                 return ERR_PTR(-ENOMEM);
1225         cqr->cpaddr = NULL;
1226         if (cplength > 0) {
1227                 cqr->cpaddr = kcalloc(cplength, sizeof(struct ccw1),
1228                                       GFP_ATOMIC | GFP_DMA);
1229                 if (cqr->cpaddr == NULL) {
1230                         kfree(cqr);
1231                         return ERR_PTR(-ENOMEM);
1232                 }
1233         }
1234         cqr->data = NULL;
1235         if (datasize > 0) {
1236                 cqr->data = kzalloc(datasize, GFP_ATOMIC | GFP_DMA);
1237                 if (cqr->data == NULL) {
1238                         kfree(cqr->cpaddr);
1239                         kfree(cqr);
1240                         return ERR_PTR(-ENOMEM);
1241                 }
1242         }
1243         cqr->magic =  magic;
1244         set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
1245         dasd_get_device(device);
1246         return cqr;
1247 }
1248 EXPORT_SYMBOL(dasd_kmalloc_request);
1249
1250 struct dasd_ccw_req *dasd_smalloc_request(int magic, int cplength,
1251                                           int datasize,
1252                                           struct dasd_device *device)
1253 {
1254         unsigned long flags;
1255         struct dasd_ccw_req *cqr;
1256         char *data;
1257         int size;
1258
1259         size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
1260         if (cplength > 0)
1261                 size += cplength * sizeof(struct ccw1);
1262         if (datasize > 0)
1263                 size += datasize;
1264         spin_lock_irqsave(&device->mem_lock, flags);
1265         cqr = (struct dasd_ccw_req *)
1266                 dasd_alloc_chunk(&device->ccw_chunks, size);
1267         spin_unlock_irqrestore(&device->mem_lock, flags);
1268         if (cqr == NULL)
1269                 return ERR_PTR(-ENOMEM);
1270         memset(cqr, 0, sizeof(struct dasd_ccw_req));
1271         data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
1272         cqr->cpaddr = NULL;
1273         if (cplength > 0) {
1274                 cqr->cpaddr = (struct ccw1 *) data;
1275                 data += cplength*sizeof(struct ccw1);
1276                 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
1277         }
1278         cqr->data = NULL;
1279         if (datasize > 0) {
1280                 cqr->data = data;
1281                 memset(cqr->data, 0, datasize);
1282         }
1283         cqr->magic = magic;
1284         set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
1285         dasd_get_device(device);
1286         return cqr;
1287 }
1288 EXPORT_SYMBOL(dasd_smalloc_request);
1289
1290 /*
1291  * Free memory of a channel program. This function needs to free all the
1292  * idal lists that might have been created by dasd_set_cda and the
1293  * struct dasd_ccw_req itself.
1294  */
1295 void dasd_kfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1296 {
1297         struct ccw1 *ccw;
1298
1299         /* Clear any idals used for the request. */
1300         ccw = cqr->cpaddr;
1301         do {
1302                 clear_normalized_cda(ccw);
1303         } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
1304         kfree(cqr->cpaddr);
1305         kfree(cqr->data);
1306         kfree(cqr);
1307         dasd_put_device(device);
1308 }
1309 EXPORT_SYMBOL(dasd_kfree_request);
1310
1311 void dasd_sfree_request(struct dasd_ccw_req *cqr, struct dasd_device *device)
1312 {
1313         unsigned long flags;
1314
1315         spin_lock_irqsave(&device->mem_lock, flags);
1316         dasd_free_chunk(&device->ccw_chunks, cqr);
1317         spin_unlock_irqrestore(&device->mem_lock, flags);
1318         dasd_put_device(device);
1319 }
1320 EXPORT_SYMBOL(dasd_sfree_request);
1321
1322 /*
1323  * Check discipline magic in cqr.
1324  */
1325 static inline int dasd_check_cqr(struct dasd_ccw_req *cqr)
1326 {
1327         struct dasd_device *device;
1328
1329         if (cqr == NULL)
1330                 return -EINVAL;
1331         device = cqr->startdev;
1332         if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
1333                 DBF_DEV_EVENT(DBF_WARNING, device,
1334                             " dasd_ccw_req 0x%08x magic doesn't match"
1335                             " discipline 0x%08x",
1336                             cqr->magic,
1337                             *(unsigned int *) device->discipline->name);
1338                 return -EINVAL;
1339         }
1340         return 0;
1341 }
1342
1343 /*
1344  * Terminate the current i/o and set the request to clear_pending.
1345  * Timer keeps device runnig.
1346  * ccw_device_clear can fail if the i/o subsystem
1347  * is in a bad mood.
1348  */
1349 int dasd_term_IO(struct dasd_ccw_req *cqr)
1350 {
1351         struct dasd_device *device;
1352         int retries, rc;
1353         char errorstring[ERRORLENGTH];
1354
1355         /* Check the cqr */
1356         rc = dasd_check_cqr(cqr);
1357         if (rc)
1358                 return rc;
1359         retries = 0;
1360         device = (struct dasd_device *) cqr->startdev;
1361         while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
1362                 rc = ccw_device_clear(device->cdev, (long) cqr);
1363                 switch (rc) {
1364                 case 0: /* termination successful */
1365                         cqr->status = DASD_CQR_CLEAR_PENDING;
1366                         cqr->stopclk = get_tod_clock();
1367                         cqr->starttime = 0;
1368                         DBF_DEV_EVENT(DBF_DEBUG, device,
1369                                       "terminate cqr %p successful",
1370                                       cqr);
1371                         break;
1372                 case -ENODEV:
1373                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
1374                                       "device gone, retry");
1375                         break;
1376                 case -EIO:
1377                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
1378                                       "I/O error, retry");
1379                         break;
1380                 case -EINVAL:
1381                         /*
1382                          * device not valid so no I/O could be running
1383                          * handle CQR as termination successful
1384                          */
1385                         cqr->status = DASD_CQR_CLEARED;
1386                         cqr->stopclk = get_tod_clock();
1387                         cqr->starttime = 0;
1388                         /* no retries for invalid devices */
1389                         cqr->retries = -1;
1390                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
1391                                       "EINVAL, handle as terminated");
1392                         /* fake rc to success */
1393                         rc = 0;
1394                         break;
1395                 case -EBUSY:
1396                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
1397                                       "device busy, retry later");
1398                         break;
1399                 default:
1400                         /* internal error 10 - unknown rc*/
1401                         snprintf(errorstring, ERRORLENGTH, "10 %d", rc);
1402                         dev_err(&device->cdev->dev, "An error occurred in the "
1403                                 "DASD device driver, reason=%s\n", errorstring);
1404                         BUG();
1405                         break;
1406                 }
1407                 retries++;
1408         }
1409         dasd_schedule_device_bh(device);
1410         return rc;
1411 }
1412 EXPORT_SYMBOL(dasd_term_IO);
1413
1414 /*
1415  * Start the i/o. This start_IO can fail if the channel is really busy.
1416  * In that case set up a timer to start the request later.
1417  */
1418 int dasd_start_IO(struct dasd_ccw_req *cqr)
1419 {
1420         struct dasd_device *device;
1421         int rc;
1422         char errorstring[ERRORLENGTH];
1423
1424         /* Check the cqr */
1425         rc = dasd_check_cqr(cqr);
1426         if (rc) {
1427                 cqr->intrc = rc;
1428                 return rc;
1429         }
1430         device = (struct dasd_device *) cqr->startdev;
1431         if (((cqr->block &&
1432               test_bit(DASD_FLAG_LOCK_STOLEN, &cqr->block->base->flags)) ||
1433              test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags)) &&
1434             !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
1435                 DBF_DEV_EVENT(DBF_DEBUG, device, "start_IO: return request %p "
1436                               "because of stolen lock", cqr);
1437                 cqr->status = DASD_CQR_ERROR;
1438                 cqr->intrc = -EPERM;
1439                 return -EPERM;
1440         }
1441         if (cqr->retries < 0) {
1442                 /* internal error 14 - start_IO run out of retries */
1443                 sprintf(errorstring, "14 %p", cqr);
1444                 dev_err(&device->cdev->dev, "An error occurred in the DASD "
1445                         "device driver, reason=%s\n", errorstring);
1446                 cqr->status = DASD_CQR_ERROR;
1447                 return -EIO;
1448         }
1449         cqr->startclk = get_tod_clock();
1450         cqr->starttime = jiffies;
1451         cqr->retries--;
1452         if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1453                 cqr->lpm &= dasd_path_get_opm(device);
1454                 if (!cqr->lpm)
1455                         cqr->lpm = dasd_path_get_opm(device);
1456         }
1457         if (cqr->cpmode == 1) {
1458                 rc = ccw_device_tm_start(device->cdev, cqr->cpaddr,
1459                                          (long) cqr, cqr->lpm);
1460         } else {
1461                 rc = ccw_device_start(device->cdev, cqr->cpaddr,
1462                                       (long) cqr, cqr->lpm, 0);
1463         }
1464         switch (rc) {
1465         case 0:
1466                 cqr->status = DASD_CQR_IN_IO;
1467                 break;
1468         case -EBUSY:
1469                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1470                               "start_IO: device busy, retry later");
1471                 break;
1472         case -ETIMEDOUT:
1473                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1474                               "start_IO: request timeout, retry later");
1475                 break;
1476         case -EACCES:
1477                 /* -EACCES indicates that the request used only a subset of the
1478                  * available paths and all these paths are gone. If the lpm of
1479                  * this request was only a subset of the opm (e.g. the ppm) then
1480                  * we just do a retry with all available paths.
1481                  * If we already use the full opm, something is amiss, and we
1482                  * need a full path verification.
1483                  */
1484                 if (test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1485                         DBF_DEV_EVENT(DBF_WARNING, device,
1486                                       "start_IO: selected paths gone (%x)",
1487                                       cqr->lpm);
1488                 } else if (cqr->lpm != dasd_path_get_opm(device)) {
1489                         cqr->lpm = dasd_path_get_opm(device);
1490                         DBF_DEV_EVENT(DBF_DEBUG, device, "%s",
1491                                       "start_IO: selected paths gone,"
1492                                       " retry on all paths");
1493                 } else {
1494                         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1495                                       "start_IO: all paths in opm gone,"
1496                                       " do path verification");
1497                         dasd_generic_last_path_gone(device);
1498                         dasd_path_no_path(device);
1499                         dasd_path_set_tbvpm(device,
1500                                           ccw_device_get_path_mask(
1501                                                   device->cdev));
1502                 }
1503                 break;
1504         case -ENODEV:
1505                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1506                               "start_IO: -ENODEV device gone, retry");
1507                 break;
1508         case -EIO:
1509                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1510                               "start_IO: -EIO device gone, retry");
1511                 break;
1512         case -EINVAL:
1513                 /* most likely caused in power management context */
1514                 DBF_DEV_EVENT(DBF_WARNING, device, "%s",
1515                               "start_IO: -EINVAL device currently "
1516                               "not accessible");
1517                 break;
1518         default:
1519                 /* internal error 11 - unknown rc */
1520                 snprintf(errorstring, ERRORLENGTH, "11 %d", rc);
1521                 dev_err(&device->cdev->dev,
1522                         "An error occurred in the DASD device driver, "
1523                         "reason=%s\n", errorstring);
1524                 BUG();
1525                 break;
1526         }
1527         cqr->intrc = rc;
1528         return rc;
1529 }
1530 EXPORT_SYMBOL(dasd_start_IO);
1531
1532 /*
1533  * Timeout function for dasd devices. This is used for different purposes
1534  *  1) missing interrupt handler for normal operation
1535  *  2) delayed start of request where start_IO failed with -EBUSY
1536  *  3) timeout for missing state change interrupts
1537  * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
1538  * DASD_CQR_QUEUED for 2) and 3).
1539  */
1540 static void dasd_device_timeout(unsigned long ptr)
1541 {
1542         unsigned long flags;
1543         struct dasd_device *device;
1544
1545         device = (struct dasd_device *) ptr;
1546         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1547         /* re-activate request queue */
1548         dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1549         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1550         dasd_schedule_device_bh(device);
1551 }
1552
1553 /*
1554  * Setup timeout for a device in jiffies.
1555  */
1556 void dasd_device_set_timer(struct dasd_device *device, int expires)
1557 {
1558         if (expires == 0)
1559                 del_timer(&device->timer);
1560         else
1561                 mod_timer(&device->timer, jiffies + expires);
1562 }
1563 EXPORT_SYMBOL(dasd_device_set_timer);
1564
1565 /*
1566  * Clear timeout for a device.
1567  */
1568 void dasd_device_clear_timer(struct dasd_device *device)
1569 {
1570         del_timer(&device->timer);
1571 }
1572 EXPORT_SYMBOL(dasd_device_clear_timer);
1573
1574 static void dasd_handle_killed_request(struct ccw_device *cdev,
1575                                        unsigned long intparm)
1576 {
1577         struct dasd_ccw_req *cqr;
1578         struct dasd_device *device;
1579
1580         if (!intparm)
1581                 return;
1582         cqr = (struct dasd_ccw_req *) intparm;
1583         if (cqr->status != DASD_CQR_IN_IO) {
1584                 DBF_EVENT_DEVID(DBF_DEBUG, cdev,
1585                                 "invalid status in handle_killed_request: "
1586                                 "%02x", cqr->status);
1587                 return;
1588         }
1589
1590         device = dasd_device_from_cdev_locked(cdev);
1591         if (IS_ERR(device)) {
1592                 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1593                                 "unable to get device from cdev");
1594                 return;
1595         }
1596
1597         if (!cqr->startdev ||
1598             device != cqr->startdev ||
1599             strncmp(cqr->startdev->discipline->ebcname,
1600                     (char *) &cqr->magic, 4)) {
1601                 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1602                                 "invalid device in request");
1603                 dasd_put_device(device);
1604                 return;
1605         }
1606
1607         /* Schedule request to be retried. */
1608         cqr->status = DASD_CQR_QUEUED;
1609
1610         dasd_device_clear_timer(device);
1611         dasd_schedule_device_bh(device);
1612         dasd_put_device(device);
1613 }
1614
1615 void dasd_generic_handle_state_change(struct dasd_device *device)
1616 {
1617         /* First of all start sense subsystem status request. */
1618         dasd_eer_snss(device);
1619
1620         dasd_device_remove_stop_bits(device, DASD_STOPPED_PENDING);
1621         dasd_schedule_device_bh(device);
1622         if (device->block)
1623                 dasd_schedule_block_bh(device->block);
1624 }
1625 EXPORT_SYMBOL_GPL(dasd_generic_handle_state_change);
1626
1627 static int dasd_check_hpf_error(struct irb *irb)
1628 {
1629         return (scsw_tm_is_valid_schxs(&irb->scsw) &&
1630             (irb->scsw.tm.sesq == SCSW_SESQ_DEV_NOFCX ||
1631              irb->scsw.tm.sesq == SCSW_SESQ_PATH_NOFCX));
1632 }
1633
1634 /*
1635  * Interrupt handler for "normal" ssch-io based dasd devices.
1636  */
1637 void dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
1638                       struct irb *irb)
1639 {
1640         struct dasd_ccw_req *cqr, *next;
1641         struct dasd_device *device;
1642         unsigned long long now;
1643         int nrf_suppressed = 0;
1644         int fp_suppressed = 0;
1645         u8 *sense = NULL;
1646         int expires;
1647
1648         cqr = (struct dasd_ccw_req *) intparm;
1649         if (IS_ERR(irb)) {
1650                 switch (PTR_ERR(irb)) {
1651                 case -EIO:
1652                         if (cqr && cqr->status == DASD_CQR_CLEAR_PENDING) {
1653                                 device = cqr->startdev;
1654                                 cqr->status = DASD_CQR_CLEARED;
1655                                 dasd_device_clear_timer(device);
1656                                 wake_up(&dasd_flush_wq);
1657                                 dasd_schedule_device_bh(device);
1658                                 return;
1659                         }
1660                         break;
1661                 case -ETIMEDOUT:
1662                         DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1663                                         "request timed out\n", __func__);
1664                         break;
1665                 default:
1666                         DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s: "
1667                                         "unknown error %ld\n", __func__,
1668                                         PTR_ERR(irb));
1669                 }
1670                 dasd_handle_killed_request(cdev, intparm);
1671                 return;
1672         }
1673
1674         now = get_tod_clock();
1675         /* check for conditions that should be handled immediately */
1676         if (!cqr ||
1677             !(scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1678               scsw_cstat(&irb->scsw) == 0)) {
1679                 if (cqr)
1680                         memcpy(&cqr->irb, irb, sizeof(*irb));
1681                 device = dasd_device_from_cdev_locked(cdev);
1682                 if (IS_ERR(device))
1683                         return;
1684                 /* ignore unsolicited interrupts for DIAG discipline */
1685                 if (device->discipline == dasd_diag_discipline_pointer) {
1686                         dasd_put_device(device);
1687                         return;
1688                 }
1689
1690                 /*
1691                  * In some cases 'File Protected' or 'No Record Found' errors
1692                  * might be expected and debug log messages for the
1693                  * corresponding interrupts shouldn't be written then.
1694                  * Check if either of the according suppress bits is set.
1695                  */
1696                 sense = dasd_get_sense(irb);
1697                 if (sense) {
1698                         fp_suppressed = (sense[1] & SNS1_FILE_PROTECTED) &&
1699                                 test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags);
1700                         nrf_suppressed = (sense[1] & SNS1_NO_REC_FOUND) &&
1701                                 test_bit(DASD_CQR_SUPPRESS_NRF, &cqr->flags);
1702                 }
1703                 if (!(fp_suppressed || nrf_suppressed))
1704                         device->discipline->dump_sense_dbf(device, irb, "int");
1705
1706                 if (device->features & DASD_FEATURE_ERPLOG)
1707                         device->discipline->dump_sense(device, cqr, irb);
1708                 device->discipline->check_for_device_change(device, cqr, irb);
1709                 dasd_put_device(device);
1710         }
1711
1712         /* check for for attention message */
1713         if (scsw_dstat(&irb->scsw) & DEV_STAT_ATTENTION) {
1714                 device = dasd_device_from_cdev_locked(cdev);
1715                 if (!IS_ERR(device)) {
1716                         device->discipline->check_attention(device,
1717                                                             irb->esw.esw1.lpum);
1718                         dasd_put_device(device);
1719                 }
1720         }
1721
1722         if (!cqr)
1723                 return;
1724
1725         device = (struct dasd_device *) cqr->startdev;
1726         if (!device ||
1727             strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
1728                 DBF_EVENT_DEVID(DBF_DEBUG, cdev, "%s",
1729                                 "invalid device in request");
1730                 return;
1731         }
1732
1733         /* Check for clear pending */
1734         if (cqr->status == DASD_CQR_CLEAR_PENDING &&
1735             scsw_fctl(&irb->scsw) & SCSW_FCTL_CLEAR_FUNC) {
1736                 cqr->status = DASD_CQR_CLEARED;
1737                 dasd_device_clear_timer(device);
1738                 wake_up(&dasd_flush_wq);
1739                 dasd_schedule_device_bh(device);
1740                 return;
1741         }
1742
1743         /* check status - the request might have been killed by dyn detach */
1744         if (cqr->status != DASD_CQR_IN_IO) {
1745                 DBF_DEV_EVENT(DBF_DEBUG, device, "invalid status: bus_id %s, "
1746                               "status %02x", dev_name(&cdev->dev), cqr->status);
1747                 return;
1748         }
1749
1750         next = NULL;
1751         expires = 0;
1752         if (scsw_dstat(&irb->scsw) == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
1753             scsw_cstat(&irb->scsw) == 0) {
1754                 /* request was completed successfully */
1755                 cqr->status = DASD_CQR_SUCCESS;
1756                 cqr->stopclk = now;
1757                 /* Start first request on queue if possible -> fast_io. */
1758                 if (cqr->devlist.next != &device->ccw_queue) {
1759                         next = list_entry(cqr->devlist.next,
1760                                           struct dasd_ccw_req, devlist);
1761                 }
1762         } else {  /* error */
1763                 /* check for HPF error
1764                  * call discipline function to requeue all requests
1765                  * and disable HPF accordingly
1766                  */
1767                 if (cqr->cpmode && dasd_check_hpf_error(irb) &&
1768                     device->discipline->handle_hpf_error)
1769                         device->discipline->handle_hpf_error(device, irb);
1770                 /*
1771                  * If we don't want complex ERP for this request, then just
1772                  * reset this and retry it in the fastpath
1773                  */
1774                 if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags) &&
1775                     cqr->retries > 0) {
1776                         if (cqr->lpm == dasd_path_get_opm(device))
1777                                 DBF_DEV_EVENT(DBF_DEBUG, device,
1778                                               "default ERP in fastpath "
1779                                               "(%i retries left)",
1780                                               cqr->retries);
1781                         if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))
1782                                 cqr->lpm = dasd_path_get_opm(device);
1783                         cqr->status = DASD_CQR_QUEUED;
1784                         next = cqr;
1785                 } else
1786                         cqr->status = DASD_CQR_ERROR;
1787         }
1788         if (next && (next->status == DASD_CQR_QUEUED) &&
1789             (!device->stopped)) {
1790                 if (device->discipline->start_IO(next) == 0)
1791                         expires = next->expires;
1792         }
1793         if (expires != 0)
1794                 dasd_device_set_timer(device, expires);
1795         else
1796                 dasd_device_clear_timer(device);
1797         dasd_schedule_device_bh(device);
1798 }
1799 EXPORT_SYMBOL(dasd_int_handler);
1800
1801 enum uc_todo dasd_generic_uc_handler(struct ccw_device *cdev, struct irb *irb)
1802 {
1803         struct dasd_device *device;
1804
1805         device = dasd_device_from_cdev_locked(cdev);
1806
1807         if (IS_ERR(device))
1808                 goto out;
1809         if (test_bit(DASD_FLAG_OFFLINE, &device->flags) ||
1810            device->state != device->target ||
1811            !device->discipline->check_for_device_change){
1812                 dasd_put_device(device);
1813                 goto out;
1814         }
1815         if (device->discipline->dump_sense_dbf)
1816                 device->discipline->dump_sense_dbf(device, irb, "uc");
1817         device->discipline->check_for_device_change(device, NULL, irb);
1818         dasd_put_device(device);
1819 out:
1820         return UC_TODO_RETRY;
1821 }
1822 EXPORT_SYMBOL_GPL(dasd_generic_uc_handler);
1823
1824 /*
1825  * If we have an error on a dasd_block layer request then we cancel
1826  * and return all further requests from the same dasd_block as well.
1827  */
1828 static void __dasd_device_recovery(struct dasd_device *device,
1829                                    struct dasd_ccw_req *ref_cqr)
1830 {
1831         struct list_head *l, *n;
1832         struct dasd_ccw_req *cqr;
1833
1834         /*
1835          * only requeue request that came from the dasd_block layer
1836          */
1837         if (!ref_cqr->block)
1838                 return;
1839
1840         list_for_each_safe(l, n, &device->ccw_queue) {
1841                 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1842                 if (cqr->status == DASD_CQR_QUEUED &&
1843                     ref_cqr->block == cqr->block) {
1844                         cqr->status = DASD_CQR_CLEARED;
1845                 }
1846         }
1847 };
1848
1849 /*
1850  * Remove those ccw requests from the queue that need to be returned
1851  * to the upper layer.
1852  */
1853 static void __dasd_device_process_ccw_queue(struct dasd_device *device,
1854                                             struct list_head *final_queue)
1855 {
1856         struct list_head *l, *n;
1857         struct dasd_ccw_req *cqr;
1858
1859         /* Process request with final status. */
1860         list_for_each_safe(l, n, &device->ccw_queue) {
1861                 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1862
1863                 /* Skip any non-final request. */
1864                 if (cqr->status == DASD_CQR_QUEUED ||
1865                     cqr->status == DASD_CQR_IN_IO ||
1866                     cqr->status == DASD_CQR_CLEAR_PENDING)
1867                         continue;
1868                 if (cqr->status == DASD_CQR_ERROR) {
1869                         __dasd_device_recovery(device, cqr);
1870                 }
1871                 /* Rechain finished requests to final queue */
1872                 list_move_tail(&cqr->devlist, final_queue);
1873         }
1874 }
1875
1876 /*
1877  * the cqrs from the final queue are returned to the upper layer
1878  * by setting a dasd_block state and calling the callback function
1879  */
1880 static void __dasd_device_process_final_queue(struct dasd_device *device,
1881                                               struct list_head *final_queue)
1882 {
1883         struct list_head *l, *n;
1884         struct dasd_ccw_req *cqr;
1885         struct dasd_block *block;
1886         void (*callback)(struct dasd_ccw_req *, void *data);
1887         void *callback_data;
1888         char errorstring[ERRORLENGTH];
1889
1890         list_for_each_safe(l, n, final_queue) {
1891                 cqr = list_entry(l, struct dasd_ccw_req, devlist);
1892                 list_del_init(&cqr->devlist);
1893                 block = cqr->block;
1894                 callback = cqr->callback;
1895                 callback_data = cqr->callback_data;
1896                 if (block)
1897                         spin_lock_bh(&block->queue_lock);
1898                 switch (cqr->status) {
1899                 case DASD_CQR_SUCCESS:
1900                         cqr->status = DASD_CQR_DONE;
1901                         break;
1902                 case DASD_CQR_ERROR:
1903                         cqr->status = DASD_CQR_NEED_ERP;
1904                         break;
1905                 case DASD_CQR_CLEARED:
1906                         cqr->status = DASD_CQR_TERMINATED;
1907                         break;
1908                 default:
1909                         /* internal error 12 - wrong cqr status*/
1910                         snprintf(errorstring, ERRORLENGTH, "12 %p %x02", cqr, cqr->status);
1911                         dev_err(&device->cdev->dev,
1912                                 "An error occurred in the DASD device driver, "
1913                                 "reason=%s\n", errorstring);
1914                         BUG();
1915                 }
1916                 if (cqr->callback != NULL)
1917                         (callback)(cqr, callback_data);
1918                 if (block)
1919                         spin_unlock_bh(&block->queue_lock);
1920         }
1921 }
1922
1923 /*
1924  * Take a look at the first request on the ccw queue and check
1925  * if it reached its expire time. If so, terminate the IO.
1926  */
1927 static void __dasd_device_check_expire(struct dasd_device *device)
1928 {
1929         struct dasd_ccw_req *cqr;
1930
1931         if (list_empty(&device->ccw_queue))
1932                 return;
1933         cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
1934         if ((cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) &&
1935             (time_after_eq(jiffies, cqr->expires + cqr->starttime))) {
1936                 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
1937                         /*
1938                          * IO in safe offline processing should not
1939                          * run out of retries
1940                          */
1941                         cqr->retries++;
1942                 }
1943                 if (device->discipline->term_IO(cqr) != 0) {
1944                         /* Hmpf, try again in 5 sec */
1945                         dev_err(&device->cdev->dev,
1946                                 "cqr %p timed out (%lus) but cannot be "
1947                                 "ended, retrying in 5 s\n",
1948                                 cqr, (cqr->expires/HZ));
1949                         cqr->expires += 5*HZ;
1950                         dasd_device_set_timer(device, 5*HZ);
1951                 } else {
1952                         dev_err(&device->cdev->dev,
1953                                 "cqr %p timed out (%lus), %i retries "
1954                                 "remaining\n", cqr, (cqr->expires/HZ),
1955                                 cqr->retries);
1956                 }
1957         }
1958 }
1959
1960 /*
1961  * return 1 when device is not eligible for IO
1962  */
1963 static int __dasd_device_is_unusable(struct dasd_device *device,
1964                                      struct dasd_ccw_req *cqr)
1965 {
1966         int mask = ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM);
1967
1968         if (test_bit(DASD_FLAG_OFFLINE, &device->flags) &&
1969             !test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
1970                 /*
1971                  * dasd is being set offline
1972                  * but it is no safe offline where we have to allow I/O
1973                  */
1974                 return 1;
1975         }
1976         if (device->stopped) {
1977                 if (device->stopped & mask) {
1978                         /* stopped and CQR will not change that. */
1979                         return 1;
1980                 }
1981                 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
1982                         /* CQR is not able to change device to
1983                          * operational. */
1984                         return 1;
1985                 }
1986                 /* CQR required to get device operational. */
1987         }
1988         return 0;
1989 }
1990
1991 /*
1992  * Take a look at the first request on the ccw queue and check
1993  * if it needs to be started.
1994  */
1995 static void __dasd_device_start_head(struct dasd_device *device)
1996 {
1997         struct dasd_ccw_req *cqr;
1998         int rc;
1999
2000         if (list_empty(&device->ccw_queue))
2001                 return;
2002         cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
2003         if (cqr->status != DASD_CQR_QUEUED)
2004                 return;
2005         /* if device is not usable return request to upper layer */
2006         if (__dasd_device_is_unusable(device, cqr)) {
2007                 cqr->intrc = -EAGAIN;
2008                 cqr->status = DASD_CQR_CLEARED;
2009                 dasd_schedule_device_bh(device);
2010                 return;
2011         }
2012
2013         rc = device->discipline->start_IO(cqr);
2014         if (rc == 0)
2015                 dasd_device_set_timer(device, cqr->expires);
2016         else if (rc == -EACCES) {
2017                 dasd_schedule_device_bh(device);
2018         } else
2019                 /* Hmpf, try again in 1/2 sec */
2020                 dasd_device_set_timer(device, 50);
2021 }
2022
2023 static void __dasd_device_check_path_events(struct dasd_device *device)
2024 {
2025         int rc;
2026
2027         if (!dasd_path_get_tbvpm(device))
2028                 return;
2029
2030         if (device->stopped &
2031             ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM))
2032                 return;
2033         rc = device->discipline->verify_path(device,
2034                                              dasd_path_get_tbvpm(device));
2035         if (rc)
2036                 dasd_device_set_timer(device, 50);
2037         else
2038                 dasd_path_clear_all_verify(device);
2039 };
2040
2041 /*
2042  * Go through all request on the dasd_device request queue,
2043  * terminate them on the cdev if necessary, and return them to the
2044  * submitting layer via callback.
2045  * Note:
2046  * Make sure that all 'submitting layers' still exist when
2047  * this function is called!. In other words, when 'device' is a base
2048  * device then all block layer requests must have been removed before
2049  * via dasd_flush_block_queue.
2050  */
2051 int dasd_flush_device_queue(struct dasd_device *device)
2052 {
2053         struct dasd_ccw_req *cqr, *n;
2054         int rc;
2055         struct list_head flush_queue;
2056
2057         INIT_LIST_HEAD(&flush_queue);
2058         spin_lock_irq(get_ccwdev_lock(device->cdev));
2059         rc = 0;
2060         list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
2061                 /* Check status and move request to flush_queue */
2062                 switch (cqr->status) {
2063                 case DASD_CQR_IN_IO:
2064                         rc = device->discipline->term_IO(cqr);
2065                         if (rc) {
2066                                 /* unable to terminate requeust */
2067                                 dev_err(&device->cdev->dev,
2068                                         "Flushing the DASD request queue "
2069                                         "failed for request %p\n", cqr);
2070                                 /* stop flush processing */
2071                                 goto finished;
2072                         }
2073                         break;
2074                 case DASD_CQR_QUEUED:
2075                         cqr->stopclk = get_tod_clock();
2076                         cqr->status = DASD_CQR_CLEARED;
2077                         break;
2078                 default: /* no need to modify the others */
2079                         break;
2080                 }
2081                 list_move_tail(&cqr->devlist, &flush_queue);
2082         }
2083 finished:
2084         spin_unlock_irq(get_ccwdev_lock(device->cdev));
2085         /*
2086          * After this point all requests must be in state CLEAR_PENDING,
2087          * CLEARED, SUCCESS or ERROR. Now wait for CLEAR_PENDING to become
2088          * one of the others.
2089          */
2090         list_for_each_entry_safe(cqr, n, &flush_queue, devlist)
2091                 wait_event(dasd_flush_wq,
2092                            (cqr->status != DASD_CQR_CLEAR_PENDING));
2093         /*
2094          * Now set each request back to TERMINATED, DONE or NEED_ERP
2095          * and call the callback function of flushed requests
2096          */
2097         __dasd_device_process_final_queue(device, &flush_queue);
2098         return rc;
2099 }
2100 EXPORT_SYMBOL_GPL(dasd_flush_device_queue);
2101
2102 /*
2103  * Acquire the device lock and process queues for the device.
2104  */
2105 static void dasd_device_tasklet(struct dasd_device *device)
2106 {
2107         struct list_head final_queue;
2108
2109         atomic_set (&device->tasklet_scheduled, 0);
2110         INIT_LIST_HEAD(&final_queue);
2111         spin_lock_irq(get_ccwdev_lock(device->cdev));
2112         /* Check expire time of first request on the ccw queue. */
2113         __dasd_device_check_expire(device);
2114         /* find final requests on ccw queue */
2115         __dasd_device_process_ccw_queue(device, &final_queue);
2116         __dasd_device_check_path_events(device);
2117         spin_unlock_irq(get_ccwdev_lock(device->cdev));
2118         /* Now call the callback function of requests with final status */
2119         __dasd_device_process_final_queue(device, &final_queue);
2120         spin_lock_irq(get_ccwdev_lock(device->cdev));
2121         /* Now check if the head of the ccw queue needs to be started. */
2122         __dasd_device_start_head(device);
2123         spin_unlock_irq(get_ccwdev_lock(device->cdev));
2124         if (waitqueue_active(&shutdown_waitq))
2125                 wake_up(&shutdown_waitq);
2126         dasd_put_device(device);
2127 }
2128
2129 /*
2130  * Schedules a call to dasd_tasklet over the device tasklet.
2131  */
2132 void dasd_schedule_device_bh(struct dasd_device *device)
2133 {
2134         /* Protect against rescheduling. */
2135         if (atomic_cmpxchg (&device->tasklet_scheduled, 0, 1) != 0)
2136                 return;
2137         dasd_get_device(device);
2138         tasklet_hi_schedule(&device->tasklet);
2139 }
2140 EXPORT_SYMBOL(dasd_schedule_device_bh);
2141
2142 void dasd_device_set_stop_bits(struct dasd_device *device, int bits)
2143 {
2144         device->stopped |= bits;
2145 }
2146 EXPORT_SYMBOL_GPL(dasd_device_set_stop_bits);
2147
2148 void dasd_device_remove_stop_bits(struct dasd_device *device, int bits)
2149 {
2150         device->stopped &= ~bits;
2151         if (!device->stopped)
2152                 wake_up(&generic_waitq);
2153 }
2154 EXPORT_SYMBOL_GPL(dasd_device_remove_stop_bits);
2155
2156 /*
2157  * Queue a request to the head of the device ccw_queue.
2158  * Start the I/O if possible.
2159  */
2160 void dasd_add_request_head(struct dasd_ccw_req *cqr)
2161 {
2162         struct dasd_device *device;
2163         unsigned long flags;
2164
2165         device = cqr->startdev;
2166         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2167         cqr->status = DASD_CQR_QUEUED;
2168         list_add(&cqr->devlist, &device->ccw_queue);
2169         /* let the bh start the request to keep them in order */
2170         dasd_schedule_device_bh(device);
2171         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2172 }
2173 EXPORT_SYMBOL(dasd_add_request_head);
2174
2175 /*
2176  * Queue a request to the tail of the device ccw_queue.
2177  * Start the I/O if possible.
2178  */
2179 void dasd_add_request_tail(struct dasd_ccw_req *cqr)
2180 {
2181         struct dasd_device *device;
2182         unsigned long flags;
2183
2184         device = cqr->startdev;
2185         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2186         cqr->status = DASD_CQR_QUEUED;
2187         list_add_tail(&cqr->devlist, &device->ccw_queue);
2188         /* let the bh start the request to keep them in order */
2189         dasd_schedule_device_bh(device);
2190         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2191 }
2192 EXPORT_SYMBOL(dasd_add_request_tail);
2193
2194 /*
2195  * Wakeup helper for the 'sleep_on' functions.
2196  */
2197 void dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
2198 {
2199         spin_lock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2200         cqr->callback_data = DASD_SLEEPON_END_TAG;
2201         spin_unlock_irq(get_ccwdev_lock(cqr->startdev->cdev));
2202         wake_up(&generic_waitq);
2203 }
2204 EXPORT_SYMBOL_GPL(dasd_wakeup_cb);
2205
2206 static inline int _wait_for_wakeup(struct dasd_ccw_req *cqr)
2207 {
2208         struct dasd_device *device;
2209         int rc;
2210
2211         device = cqr->startdev;
2212         spin_lock_irq(get_ccwdev_lock(device->cdev));
2213         rc = (cqr->callback_data == DASD_SLEEPON_END_TAG);
2214         spin_unlock_irq(get_ccwdev_lock(device->cdev));
2215         return rc;
2216 }
2217
2218 /*
2219  * checks if error recovery is necessary, returns 1 if yes, 0 otherwise.
2220  */
2221 static int __dasd_sleep_on_erp(struct dasd_ccw_req *cqr)
2222 {
2223         struct dasd_device *device;
2224         dasd_erp_fn_t erp_fn;
2225
2226         if (cqr->status == DASD_CQR_FILLED)
2227                 return 0;
2228         device = cqr->startdev;
2229         if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2230                 if (cqr->status == DASD_CQR_TERMINATED) {
2231                         device->discipline->handle_terminated_request(cqr);
2232                         return 1;
2233                 }
2234                 if (cqr->status == DASD_CQR_NEED_ERP) {
2235                         erp_fn = device->discipline->erp_action(cqr);
2236                         erp_fn(cqr);
2237                         return 1;
2238                 }
2239                 if (cqr->status == DASD_CQR_FAILED)
2240                         dasd_log_sense(cqr, &cqr->irb);
2241                 if (cqr->refers) {
2242                         __dasd_process_erp(device, cqr);
2243                         return 1;
2244                 }
2245         }
2246         return 0;
2247 }
2248
2249 static int __dasd_sleep_on_loop_condition(struct dasd_ccw_req *cqr)
2250 {
2251         if (test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags)) {
2252                 if (cqr->refers) /* erp is not done yet */
2253                         return 1;
2254                 return ((cqr->status != DASD_CQR_DONE) &&
2255                         (cqr->status != DASD_CQR_FAILED));
2256         } else
2257                 return (cqr->status == DASD_CQR_FILLED);
2258 }
2259
2260 static int _dasd_sleep_on(struct dasd_ccw_req *maincqr, int interruptible)
2261 {
2262         struct dasd_device *device;
2263         int rc;
2264         struct list_head ccw_queue;
2265         struct dasd_ccw_req *cqr;
2266
2267         INIT_LIST_HEAD(&ccw_queue);
2268         maincqr->status = DASD_CQR_FILLED;
2269         device = maincqr->startdev;
2270         list_add(&maincqr->blocklist, &ccw_queue);
2271         for (cqr = maincqr;  __dasd_sleep_on_loop_condition(cqr);
2272              cqr = list_first_entry(&ccw_queue,
2273                                     struct dasd_ccw_req, blocklist)) {
2274
2275                 if (__dasd_sleep_on_erp(cqr))
2276                         continue;
2277                 if (cqr->status != DASD_CQR_FILLED) /* could be failed */
2278                         continue;
2279                 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2280                     !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2281                         cqr->status = DASD_CQR_FAILED;
2282                         cqr->intrc = -EPERM;
2283                         continue;
2284                 }
2285                 /* Non-temporary stop condition will trigger fail fast */
2286                 if (device->stopped & ~DASD_STOPPED_PENDING &&
2287                     test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2288                     (!dasd_eer_enabled(device))) {
2289                         cqr->status = DASD_CQR_FAILED;
2290                         cqr->intrc = -ENOLINK;
2291                         continue;
2292                 }
2293                 /*
2294                  * Don't try to start requests if device is in
2295                  * offline processing, it might wait forever
2296                  */
2297                 if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
2298                         cqr->status = DASD_CQR_FAILED;
2299                         cqr->intrc = -ENODEV;
2300                         continue;
2301                 }
2302                 /*
2303                  * Don't try to start requests if device is stopped
2304                  * except path verification requests
2305                  */
2306                 if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
2307                         if (interruptible) {
2308                                 rc = wait_event_interruptible(
2309                                         generic_waitq, !(device->stopped));
2310                                 if (rc == -ERESTARTSYS) {
2311                                         cqr->status = DASD_CQR_FAILED;
2312                                         maincqr->intrc = rc;
2313                                         continue;
2314                                 }
2315                         } else
2316                                 wait_event(generic_waitq, !(device->stopped));
2317                 }
2318                 if (!cqr->callback)
2319                         cqr->callback = dasd_wakeup_cb;
2320
2321                 cqr->callback_data = DASD_SLEEPON_START_TAG;
2322                 dasd_add_request_tail(cqr);
2323                 if (interruptible) {
2324                         rc = wait_event_interruptible(
2325                                 generic_waitq, _wait_for_wakeup(cqr));
2326                         if (rc == -ERESTARTSYS) {
2327                                 dasd_cancel_req(cqr);
2328                                 /* wait (non-interruptible) for final status */
2329                                 wait_event(generic_waitq,
2330                                            _wait_for_wakeup(cqr));
2331                                 cqr->status = DASD_CQR_FAILED;
2332                                 maincqr->intrc = rc;
2333                                 continue;
2334                         }
2335                 } else
2336                         wait_event(generic_waitq, _wait_for_wakeup(cqr));
2337         }
2338
2339         maincqr->endclk = get_tod_clock();
2340         if ((maincqr->status != DASD_CQR_DONE) &&
2341             (maincqr->intrc != -ERESTARTSYS))
2342                 dasd_log_sense(maincqr, &maincqr->irb);
2343         if (maincqr->status == DASD_CQR_DONE)
2344                 rc = 0;
2345         else if (maincqr->intrc)
2346                 rc = maincqr->intrc;
2347         else
2348                 rc = -EIO;
2349         return rc;
2350 }
2351
2352 static inline int _wait_for_wakeup_queue(struct list_head *ccw_queue)
2353 {
2354         struct dasd_ccw_req *cqr;
2355
2356         list_for_each_entry(cqr, ccw_queue, blocklist) {
2357                 if (cqr->callback_data != DASD_SLEEPON_END_TAG)
2358                         return 0;
2359         }
2360
2361         return 1;
2362 }
2363
2364 static int _dasd_sleep_on_queue(struct list_head *ccw_queue, int interruptible)
2365 {
2366         struct dasd_device *device;
2367         struct dasd_ccw_req *cqr, *n;
2368         u8 *sense = NULL;
2369         int rc;
2370
2371 retry:
2372         list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) {
2373                 device = cqr->startdev;
2374                 if (cqr->status != DASD_CQR_FILLED) /*could be failed*/
2375                         continue;
2376
2377                 if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2378                     !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2379                         cqr->status = DASD_CQR_FAILED;
2380                         cqr->intrc = -EPERM;
2381                         continue;
2382                 }
2383                 /*Non-temporary stop condition will trigger fail fast*/
2384                 if (device->stopped & ~DASD_STOPPED_PENDING &&
2385                     test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2386                     !dasd_eer_enabled(device)) {
2387                         cqr->status = DASD_CQR_FAILED;
2388                         cqr->intrc = -EAGAIN;
2389                         continue;
2390                 }
2391
2392                 /*Don't try to start requests if device is stopped*/
2393                 if (interruptible) {
2394                         rc = wait_event_interruptible(
2395                                 generic_waitq, !device->stopped);
2396                         if (rc == -ERESTARTSYS) {
2397                                 cqr->status = DASD_CQR_FAILED;
2398                                 cqr->intrc = rc;
2399                                 continue;
2400                         }
2401                 } else
2402                         wait_event(generic_waitq, !(device->stopped));
2403
2404                 if (!cqr->callback)
2405                         cqr->callback = dasd_wakeup_cb;
2406                 cqr->callback_data = DASD_SLEEPON_START_TAG;
2407                 dasd_add_request_tail(cqr);
2408         }
2409
2410         wait_event(generic_waitq, _wait_for_wakeup_queue(ccw_queue));
2411
2412         rc = 0;
2413         list_for_each_entry_safe(cqr, n, ccw_queue, blocklist) {
2414                 /*
2415                  * In some cases the 'File Protected' or 'Incorrect Length'
2416                  * error might be expected and error recovery would be
2417                  * unnecessary in these cases.  Check if the according suppress
2418                  * bit is set.
2419                  */
2420                 sense = dasd_get_sense(&cqr->irb);
2421                 if (sense && sense[1] & SNS1_FILE_PROTECTED &&
2422                     test_bit(DASD_CQR_SUPPRESS_FP, &cqr->flags))
2423                         continue;
2424                 if (scsw_cstat(&cqr->irb.scsw) == 0x40 &&
2425                     test_bit(DASD_CQR_SUPPRESS_IL, &cqr->flags))
2426                         continue;
2427
2428                 /*
2429                  * for alias devices simplify error recovery and
2430                  * return to upper layer
2431                  * do not skip ERP requests
2432                  */
2433                 if (cqr->startdev != cqr->basedev && !cqr->refers &&
2434                     (cqr->status == DASD_CQR_TERMINATED ||
2435                      cqr->status == DASD_CQR_NEED_ERP))
2436                         return -EAGAIN;
2437
2438                 /* normal recovery for basedev IO */
2439                 if (__dasd_sleep_on_erp(cqr))
2440                         /* handle erp first */
2441                         goto retry;
2442         }
2443
2444         return 0;
2445 }
2446
2447 /*
2448  * Queue a request to the tail of the device ccw_queue and wait for
2449  * it's completion.
2450  */
2451 int dasd_sleep_on(struct dasd_ccw_req *cqr)
2452 {
2453         return _dasd_sleep_on(cqr, 0);
2454 }
2455 EXPORT_SYMBOL(dasd_sleep_on);
2456
2457 /*
2458  * Start requests from a ccw_queue and wait for their completion.
2459  */
2460 int dasd_sleep_on_queue(struct list_head *ccw_queue)
2461 {
2462         return _dasd_sleep_on_queue(ccw_queue, 0);
2463 }
2464 EXPORT_SYMBOL(dasd_sleep_on_queue);
2465
2466 /*
2467  * Queue a request to the tail of the device ccw_queue and wait
2468  * interruptible for it's completion.
2469  */
2470 int dasd_sleep_on_interruptible(struct dasd_ccw_req *cqr)
2471 {
2472         return _dasd_sleep_on(cqr, 1);
2473 }
2474 EXPORT_SYMBOL(dasd_sleep_on_interruptible);
2475
2476 /*
2477  * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
2478  * for eckd devices) the currently running request has to be terminated
2479  * and be put back to status queued, before the special request is added
2480  * to the head of the queue. Then the special request is waited on normally.
2481  */
2482 static inline int _dasd_term_running_cqr(struct dasd_device *device)
2483 {
2484         struct dasd_ccw_req *cqr;
2485         int rc;
2486
2487         if (list_empty(&device->ccw_queue))
2488                 return 0;
2489         cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
2490         rc = device->discipline->term_IO(cqr);
2491         if (!rc)
2492                 /*
2493                  * CQR terminated because a more important request is pending.
2494                  * Undo decreasing of retry counter because this is
2495                  * not an error case.
2496                  */
2497                 cqr->retries++;
2498         return rc;
2499 }
2500
2501 int dasd_sleep_on_immediatly(struct dasd_ccw_req *cqr)
2502 {
2503         struct dasd_device *device;
2504         int rc;
2505
2506         device = cqr->startdev;
2507         if (test_bit(DASD_FLAG_LOCK_STOLEN, &device->flags) &&
2508             !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2509                 cqr->status = DASD_CQR_FAILED;
2510                 cqr->intrc = -EPERM;
2511                 return -EIO;
2512         }
2513         spin_lock_irq(get_ccwdev_lock(device->cdev));
2514         rc = _dasd_term_running_cqr(device);
2515         if (rc) {
2516                 spin_unlock_irq(get_ccwdev_lock(device->cdev));
2517                 return rc;
2518         }
2519         cqr->callback = dasd_wakeup_cb;
2520         cqr->callback_data = DASD_SLEEPON_START_TAG;
2521         cqr->status = DASD_CQR_QUEUED;
2522         /*
2523          * add new request as second
2524          * first the terminated cqr needs to be finished
2525          */
2526         list_add(&cqr->devlist, device->ccw_queue.next);
2527
2528         /* let the bh start the request to keep them in order */
2529         dasd_schedule_device_bh(device);
2530
2531         spin_unlock_irq(get_ccwdev_lock(device->cdev));
2532
2533         wait_event(generic_waitq, _wait_for_wakeup(cqr));
2534
2535         if (cqr->status == DASD_CQR_DONE)
2536                 rc = 0;
2537         else if (cqr->intrc)
2538                 rc = cqr->intrc;
2539         else
2540                 rc = -EIO;
2541
2542         /* kick tasklets */
2543         dasd_schedule_device_bh(device);
2544         if (device->block)
2545                 dasd_schedule_block_bh(device->block);
2546
2547         return rc;
2548 }
2549 EXPORT_SYMBOL(dasd_sleep_on_immediatly);
2550
2551 /*
2552  * Cancels a request that was started with dasd_sleep_on_req.
2553  * This is useful to timeout requests. The request will be
2554  * terminated if it is currently in i/o.
2555  * Returns 0 if request termination was successful
2556  *         negative error code if termination failed
2557  * Cancellation of a request is an asynchronous operation! The calling
2558  * function has to wait until the request is properly returned via callback.
2559  */
2560 int dasd_cancel_req(struct dasd_ccw_req *cqr)
2561 {
2562         struct dasd_device *device = cqr->startdev;
2563         unsigned long flags;
2564         int rc;
2565
2566         rc = 0;
2567         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
2568         switch (cqr->status) {
2569         case DASD_CQR_QUEUED:
2570                 /* request was not started - just set to cleared */
2571                 cqr->status = DASD_CQR_CLEARED;
2572                 if (cqr->callback_data == DASD_SLEEPON_START_TAG)
2573                         cqr->callback_data = DASD_SLEEPON_END_TAG;
2574                 break;
2575         case DASD_CQR_IN_IO:
2576                 /* request in IO - terminate IO and release again */
2577                 rc = device->discipline->term_IO(cqr);
2578                 if (rc) {
2579                         dev_err(&device->cdev->dev,
2580                                 "Cancelling request %p failed with rc=%d\n",
2581                                 cqr, rc);
2582                 } else {
2583                         cqr->stopclk = get_tod_clock();
2584                 }
2585                 break;
2586         default: /* already finished or clear pending - do nothing */
2587                 break;
2588         }
2589         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
2590         dasd_schedule_device_bh(device);
2591         return rc;
2592 }
2593 EXPORT_SYMBOL(dasd_cancel_req);
2594
2595 /*
2596  * SECTION: Operations of the dasd_block layer.
2597  */
2598
2599 /*
2600  * Timeout function for dasd_block. This is used when the block layer
2601  * is waiting for something that may not come reliably, (e.g. a state
2602  * change interrupt)
2603  */
2604 static void dasd_block_timeout(unsigned long ptr)
2605 {
2606         unsigned long flags;
2607         struct dasd_block *block;
2608
2609         block = (struct dasd_block *) ptr;
2610         spin_lock_irqsave(get_ccwdev_lock(block->base->cdev), flags);
2611         /* re-activate request queue */
2612         dasd_device_remove_stop_bits(block->base, DASD_STOPPED_PENDING);
2613         spin_unlock_irqrestore(get_ccwdev_lock(block->base->cdev), flags);
2614         dasd_schedule_block_bh(block);
2615 }
2616
2617 /*
2618  * Setup timeout for a dasd_block in jiffies.
2619  */
2620 void dasd_block_set_timer(struct dasd_block *block, int expires)
2621 {
2622         if (expires == 0)
2623                 del_timer(&block->timer);
2624         else
2625                 mod_timer(&block->timer, jiffies + expires);
2626 }
2627 EXPORT_SYMBOL(dasd_block_set_timer);
2628
2629 /*
2630  * Clear timeout for a dasd_block.
2631  */
2632 void dasd_block_clear_timer(struct dasd_block *block)
2633 {
2634         del_timer(&block->timer);
2635 }
2636 EXPORT_SYMBOL(dasd_block_clear_timer);
2637
2638 /*
2639  * Process finished error recovery ccw.
2640  */
2641 static void __dasd_process_erp(struct dasd_device *device,
2642                                struct dasd_ccw_req *cqr)
2643 {
2644         dasd_erp_fn_t erp_fn;
2645
2646         if (cqr->status == DASD_CQR_DONE)
2647                 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
2648         else
2649                 dev_err(&device->cdev->dev, "ERP failed for the DASD\n");
2650         erp_fn = device->discipline->erp_postaction(cqr);
2651         erp_fn(cqr);
2652 }
2653
2654 /*
2655  * Fetch requests from the block device queue.
2656  */
2657 static void __dasd_process_request_queue(struct dasd_block *block)
2658 {
2659         struct request_queue *queue;
2660         struct request *req;
2661         struct dasd_ccw_req *cqr;
2662         struct dasd_device *basedev;
2663         unsigned long flags;
2664         queue = block->request_queue;
2665         basedev = block->base;
2666         /* No queue ? Then there is nothing to do. */
2667         if (queue == NULL)
2668                 return;
2669
2670         /*
2671          * We requeue request from the block device queue to the ccw
2672          * queue only in two states. In state DASD_STATE_READY the
2673          * partition detection is done and we need to requeue requests
2674          * for that. State DASD_STATE_ONLINE is normal block device
2675          * operation.
2676          */
2677         if (basedev->state < DASD_STATE_READY) {
2678                 while ((req = blk_fetch_request(block->request_queue)))
2679                         __blk_end_request_all(req, BLK_STS_IOERR);
2680                 return;
2681         }
2682
2683         /*
2684          * if device is stopped do not fetch new requests
2685          * except failfast is active which will let requests fail
2686          * immediately in __dasd_block_start_head()
2687          */
2688         if (basedev->stopped && !(basedev->features & DASD_FEATURE_FAILFAST))
2689                 return;
2690
2691         /* Now we try to fetch requests from the request queue */
2692         while ((req = blk_peek_request(queue))) {
2693                 if (basedev->features & DASD_FEATURE_READONLY &&
2694                     rq_data_dir(req) == WRITE) {
2695                         DBF_DEV_EVENT(DBF_ERR, basedev,
2696                                       "Rejecting write request %p",
2697                                       req);
2698                         blk_start_request(req);
2699                         __blk_end_request_all(req, BLK_STS_IOERR);
2700                         continue;
2701                 }
2702                 if (test_bit(DASD_FLAG_ABORTALL, &basedev->flags) &&
2703                     (basedev->features & DASD_FEATURE_FAILFAST ||
2704                      blk_noretry_request(req))) {
2705                         DBF_DEV_EVENT(DBF_ERR, basedev,
2706                                       "Rejecting failfast request %p",
2707                                       req);
2708                         blk_start_request(req);
2709                         __blk_end_request_all(req, BLK_STS_TIMEOUT);
2710                         continue;
2711                 }
2712                 cqr = basedev->discipline->build_cp(basedev, block, req);
2713                 if (IS_ERR(cqr)) {
2714                         if (PTR_ERR(cqr) == -EBUSY)
2715                                 break;  /* normal end condition */
2716                         if (PTR_ERR(cqr) == -ENOMEM)
2717                                 break;  /* terminate request queue loop */
2718                         if (PTR_ERR(cqr) == -EAGAIN) {
2719                                 /*
2720                                  * The current request cannot be build right
2721                                  * now, we have to try later. If this request
2722                                  * is the head-of-queue we stop the device
2723                                  * for 1/2 second.
2724                                  */
2725                                 if (!list_empty(&block->ccw_queue))
2726                                         break;
2727                                 spin_lock_irqsave(
2728                                         get_ccwdev_lock(basedev->cdev), flags);
2729                                 dasd_device_set_stop_bits(basedev,
2730                                                           DASD_STOPPED_PENDING);
2731                                 spin_unlock_irqrestore(
2732                                         get_ccwdev_lock(basedev->cdev), flags);
2733                                 dasd_block_set_timer(block, HZ/2);
2734                                 break;
2735                         }
2736                         DBF_DEV_EVENT(DBF_ERR, basedev,
2737                                       "CCW creation failed (rc=%ld) "
2738                                       "on request %p",
2739                                       PTR_ERR(cqr), req);
2740                         blk_start_request(req);
2741                         __blk_end_request_all(req, BLK_STS_IOERR);
2742                         continue;
2743                 }
2744                 /*
2745                  *  Note: callback is set to dasd_return_cqr_cb in
2746                  * __dasd_block_start_head to cover erp requests as well
2747                  */
2748                 cqr->callback_data = (void *) req;
2749                 cqr->status = DASD_CQR_FILLED;
2750                 req->completion_data = cqr;
2751                 blk_start_request(req);
2752                 list_add_tail(&cqr->blocklist, &block->ccw_queue);
2753                 INIT_LIST_HEAD(&cqr->devlist);
2754                 dasd_profile_start(block, cqr, req);
2755         }
2756 }
2757
2758 static void __dasd_cleanup_cqr(struct dasd_ccw_req *cqr)
2759 {
2760         struct request *req;
2761         int status;
2762         blk_status_t error = BLK_STS_OK;
2763
2764         req = (struct request *) cqr->callback_data;
2765         dasd_profile_end(cqr->block, cqr, req);
2766
2767         status = cqr->block->base->discipline->free_cp(cqr, req);
2768         if (status < 0)
2769                 error = errno_to_blk_status(status);
2770         else if (status == 0) {
2771                 switch (cqr->intrc) {
2772                 case -EPERM:
2773                         error = BLK_STS_NEXUS;
2774                         break;
2775                 case -ENOLINK:
2776                         error = BLK_STS_TRANSPORT;
2777                         break;
2778                 case -ETIMEDOUT:
2779                         error = BLK_STS_TIMEOUT;
2780                         break;
2781                 default:
2782                         error = BLK_STS_IOERR;
2783                         break;
2784                 }
2785         }
2786         __blk_end_request_all(req, error);
2787 }
2788
2789 /*
2790  * Process ccw request queue.
2791  */
2792 static void __dasd_process_block_ccw_queue(struct dasd_block *block,
2793                                            struct list_head *final_queue)
2794 {
2795         struct list_head *l, *n;
2796         struct dasd_ccw_req *cqr;
2797         dasd_erp_fn_t erp_fn;
2798         unsigned long flags;
2799         struct dasd_device *base = block->base;
2800
2801 restart:
2802         /* Process request with final status. */
2803         list_for_each_safe(l, n, &block->ccw_queue) {
2804                 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2805                 if (cqr->status != DASD_CQR_DONE &&
2806                     cqr->status != DASD_CQR_FAILED &&
2807                     cqr->status != DASD_CQR_NEED_ERP &&
2808                     cqr->status != DASD_CQR_TERMINATED)
2809                         continue;
2810
2811                 if (cqr->status == DASD_CQR_TERMINATED) {
2812                         base->discipline->handle_terminated_request(cqr);
2813                         goto restart;
2814                 }
2815
2816                 /*  Process requests that may be recovered */
2817                 if (cqr->status == DASD_CQR_NEED_ERP) {
2818                         erp_fn = base->discipline->erp_action(cqr);
2819                         if (IS_ERR(erp_fn(cqr)))
2820                                 continue;
2821                         goto restart;
2822                 }
2823
2824                 /* log sense for fatal error */
2825                 if (cqr->status == DASD_CQR_FAILED) {
2826                         dasd_log_sense(cqr, &cqr->irb);
2827                 }
2828
2829                 /* First of all call extended error reporting. */
2830                 if (dasd_eer_enabled(base) &&
2831                     cqr->status == DASD_CQR_FAILED) {
2832                         dasd_eer_write(base, cqr, DASD_EER_FATALERROR);
2833
2834                         /* restart request  */
2835                         cqr->status = DASD_CQR_FILLED;
2836                         cqr->retries = 255;
2837                         spin_lock_irqsave(get_ccwdev_lock(base->cdev), flags);
2838                         dasd_device_set_stop_bits(base, DASD_STOPPED_QUIESCE);
2839                         spin_unlock_irqrestore(get_ccwdev_lock(base->cdev),
2840                                                flags);
2841                         goto restart;
2842                 }
2843
2844                 /* Process finished ERP request. */
2845                 if (cqr->refers) {
2846                         __dasd_process_erp(base, cqr);
2847                         goto restart;
2848                 }
2849
2850                 /* Rechain finished requests to final queue */
2851                 cqr->endclk = get_tod_clock();
2852                 list_move_tail(&cqr->blocklist, final_queue);
2853         }
2854 }
2855
2856 static void dasd_return_cqr_cb(struct dasd_ccw_req *cqr, void *data)
2857 {
2858         dasd_schedule_block_bh(cqr->block);
2859 }
2860
2861 static void __dasd_block_start_head(struct dasd_block *block)
2862 {
2863         struct dasd_ccw_req *cqr;
2864
2865         if (list_empty(&block->ccw_queue))
2866                 return;
2867         /* We allways begin with the first requests on the queue, as some
2868          * of previously started requests have to be enqueued on a
2869          * dasd_device again for error recovery.
2870          */
2871         list_for_each_entry(cqr, &block->ccw_queue, blocklist) {
2872                 if (cqr->status != DASD_CQR_FILLED)
2873                         continue;
2874                 if (test_bit(DASD_FLAG_LOCK_STOLEN, &block->base->flags) &&
2875                     !test_bit(DASD_CQR_ALLOW_SLOCK, &cqr->flags)) {
2876                         cqr->status = DASD_CQR_FAILED;
2877                         cqr->intrc = -EPERM;
2878                         dasd_schedule_block_bh(block);
2879                         continue;
2880                 }
2881                 /* Non-temporary stop condition will trigger fail fast */
2882                 if (block->base->stopped & ~DASD_STOPPED_PENDING &&
2883                     test_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags) &&
2884                     (!dasd_eer_enabled(block->base))) {
2885                         cqr->status = DASD_CQR_FAILED;
2886                         cqr->intrc = -ENOLINK;
2887                         dasd_schedule_block_bh(block);
2888                         continue;
2889                 }
2890                 /* Don't try to start requests if device is stopped */
2891                 if (block->base->stopped)
2892                         return;
2893
2894                 /* just a fail safe check, should not happen */
2895                 if (!cqr->startdev)
2896                         cqr->startdev = block->base;
2897
2898                 /* make sure that the requests we submit find their way back */
2899                 cqr->callback = dasd_return_cqr_cb;
2900
2901                 dasd_add_request_tail(cqr);
2902         }
2903 }
2904
2905 /*
2906  * Central dasd_block layer routine. Takes requests from the generic
2907  * block layer request queue, creates ccw requests, enqueues them on
2908  * a dasd_device and processes ccw requests that have been returned.
2909  */
2910 static void dasd_block_tasklet(struct dasd_block *block)
2911 {
2912         struct list_head final_queue;
2913         struct list_head *l, *n;
2914         struct dasd_ccw_req *cqr;
2915
2916         atomic_set(&block->tasklet_scheduled, 0);
2917         INIT_LIST_HEAD(&final_queue);
2918         spin_lock(&block->queue_lock);
2919         /* Finish off requests on ccw queue */
2920         __dasd_process_block_ccw_queue(block, &final_queue);
2921         spin_unlock(&block->queue_lock);
2922         /* Now call the callback function of requests with final status */
2923         spin_lock_irq(&block->request_queue_lock);
2924         list_for_each_safe(l, n, &final_queue) {
2925                 cqr = list_entry(l, struct dasd_ccw_req, blocklist);
2926                 list_del_init(&cqr->blocklist);
2927                 __dasd_cleanup_cqr(cqr);
2928         }
2929         spin_lock(&block->queue_lock);
2930         /* Get new request from the block device request queue */
2931         __dasd_process_request_queue(block);
2932         /* Now check if the head of the ccw queue needs to be started. */
2933         __dasd_block_start_head(block);
2934         spin_unlock(&block->queue_lock);
2935         spin_unlock_irq(&block->request_queue_lock);
2936         if (waitqueue_active(&shutdown_waitq))
2937                 wake_up(&shutdown_waitq);
2938         dasd_put_device(block->base);
2939 }
2940
2941 static void _dasd_wake_block_flush_cb(struct dasd_ccw_req *cqr, void *data)
2942 {
2943         wake_up(&dasd_flush_wq);
2944 }
2945
2946 /*
2947  * Requeue a request back to the block request queue
2948  * only works for block requests
2949  */
2950 static int _dasd_requeue_request(struct dasd_ccw_req *cqr)
2951 {
2952         struct dasd_block *block = cqr->block;
2953         struct request *req;
2954         unsigned long flags;
2955
2956         if (!block)
2957                 return -EINVAL;
2958         spin_lock_irqsave(&block->request_queue_lock, flags);
2959         req = (struct request *) cqr->callback_data;
2960         blk_requeue_request(block->request_queue, req);
2961         spin_unlock_irqrestore(&block->request_queue_lock, flags);
2962
2963         return 0;
2964 }
2965
2966 /*
2967  * Go through all request on the dasd_block request queue, cancel them
2968  * on the respective dasd_device, and return them to the generic
2969  * block layer.
2970  */
2971 static int dasd_flush_block_queue(struct dasd_block *block)
2972 {
2973         struct dasd_ccw_req *cqr, *n;
2974         int rc, i;
2975         struct list_head flush_queue;
2976
2977         INIT_LIST_HEAD(&flush_queue);
2978         spin_lock_bh(&block->queue_lock);
2979         rc = 0;
2980 restart:
2981         list_for_each_entry_safe(cqr, n, &block->ccw_queue, blocklist) {
2982                 /* if this request currently owned by a dasd_device cancel it */
2983                 if (cqr->status >= DASD_CQR_QUEUED)
2984                         rc = dasd_cancel_req(cqr);
2985                 if (rc < 0)
2986                         break;
2987                 /* Rechain request (including erp chain) so it won't be
2988                  * touched by the dasd_block_tasklet anymore.
2989                  * Replace the callback so we notice when the request
2990                  * is returned from the dasd_device layer.
2991                  */
2992                 cqr->callback = _dasd_wake_block_flush_cb;
2993                 for (i = 0; cqr != NULL; cqr = cqr->refers, i++)
2994                         list_move_tail(&cqr->blocklist, &flush_queue);
2995                 if (i > 1)
2996                         /* moved more than one request - need to restart */
2997                         goto restart;
2998         }
2999         spin_unlock_bh(&block->queue_lock);
3000         /* Now call the callback function of flushed requests */
3001 restart_cb:
3002         list_for_each_entry_safe(cqr, n, &flush_queue, blocklist) {
3003                 wait_event(dasd_flush_wq, (cqr->status < DASD_CQR_QUEUED));
3004                 /* Process finished ERP request. */
3005                 if (cqr->refers) {
3006                         spin_lock_bh(&block->queue_lock);
3007                         __dasd_process_erp(block->base, cqr);
3008                         spin_unlock_bh(&block->queue_lock);
3009                         /* restart list_for_xx loop since dasd_process_erp
3010                          * might remove multiple elements */
3011                         goto restart_cb;
3012                 }
3013                 /* call the callback function */
3014                 spin_lock_irq(&block->request_queue_lock);
3015                 cqr->endclk = get_tod_clock();
3016                 list_del_init(&cqr->blocklist);
3017                 __dasd_cleanup_cqr(cqr);
3018                 spin_unlock_irq(&block->request_queue_lock);
3019         }
3020         return rc;
3021 }
3022
3023 /*
3024  * Schedules a call to dasd_tasklet over the device tasklet.
3025  */
3026 void dasd_schedule_block_bh(struct dasd_block *block)
3027 {
3028         /* Protect against rescheduling. */
3029         if (atomic_cmpxchg(&block->tasklet_scheduled, 0, 1) != 0)
3030                 return;
3031         /* life cycle of block is bound to it's base device */
3032         dasd_get_device(block->base);
3033         tasklet_hi_schedule(&block->tasklet);
3034 }
3035 EXPORT_SYMBOL(dasd_schedule_block_bh);
3036
3037
3038 /*
3039  * SECTION: external block device operations
3040  * (request queue handling, open, release, etc.)
3041  */
3042
3043 /*
3044  * Dasd request queue function. Called from ll_rw_blk.c
3045  */
3046 static void do_dasd_request(struct request_queue *queue)
3047 {
3048         struct dasd_block *block;
3049
3050         block = queue->queuedata;
3051         spin_lock(&block->queue_lock);
3052         /* Get new request from the block device request queue */
3053         __dasd_process_request_queue(block);
3054         /* Now check if the head of the ccw queue needs to be started. */
3055         __dasd_block_start_head(block);
3056         spin_unlock(&block->queue_lock);
3057 }
3058
3059 /*
3060  * Block timeout callback, called from the block layer
3061  *
3062  * request_queue lock is held on entry.
3063  *
3064  * Return values:
3065  * BLK_EH_RESET_TIMER if the request should be left running
3066  * BLK_EH_NOT_HANDLED if the request is handled or terminated
3067  *                    by the driver.
3068  */
3069 enum blk_eh_timer_return dasd_times_out(struct request *req)
3070 {
3071         struct dasd_ccw_req *cqr = req->completion_data;
3072         struct dasd_block *block = req->q->queuedata;
3073         struct dasd_device *device;
3074         int rc = 0;
3075
3076         if (!cqr)
3077                 return BLK_EH_NOT_HANDLED;
3078
3079         device = cqr->startdev ? cqr->startdev : block->base;
3080         if (!device->blk_timeout)
3081                 return BLK_EH_RESET_TIMER;
3082         DBF_DEV_EVENT(DBF_WARNING, device,
3083                       " dasd_times_out cqr %p status %x",
3084                       cqr, cqr->status);
3085
3086         spin_lock(&block->queue_lock);
3087         spin_lock(get_ccwdev_lock(device->cdev));
3088         cqr->retries = -1;
3089         cqr->intrc = -ETIMEDOUT;
3090         if (cqr->status >= DASD_CQR_QUEUED) {
3091                 spin_unlock(get_ccwdev_lock(device->cdev));
3092                 rc = dasd_cancel_req(cqr);
3093         } else if (cqr->status == DASD_CQR_FILLED ||
3094                    cqr->status == DASD_CQR_NEED_ERP) {
3095                 cqr->status = DASD_CQR_TERMINATED;
3096                 spin_unlock(get_ccwdev_lock(device->cdev));
3097         } else if (cqr->status == DASD_CQR_IN_ERP) {
3098                 struct dasd_ccw_req *searchcqr, *nextcqr, *tmpcqr;
3099
3100                 list_for_each_entry_safe(searchcqr, nextcqr,
3101                                          &block->ccw_queue, blocklist) {
3102                         tmpcqr = searchcqr;
3103                         while (tmpcqr->refers)
3104                                 tmpcqr = tmpcqr->refers;
3105                         if (tmpcqr != cqr)
3106                                 continue;
3107                         /* searchcqr is an ERP request for cqr */
3108                         searchcqr->retries = -1;
3109                         searchcqr->intrc = -ETIMEDOUT;
3110                         if (searchcqr->status >= DASD_CQR_QUEUED) {
3111                                 spin_unlock(get_ccwdev_lock(device->cdev));
3112                                 rc = dasd_cancel_req(searchcqr);
3113                                 spin_lock(get_ccwdev_lock(device->cdev));
3114                         } else if ((searchcqr->status == DASD_CQR_FILLED) ||
3115                                    (searchcqr->status == DASD_CQR_NEED_ERP)) {
3116                                 searchcqr->status = DASD_CQR_TERMINATED;
3117                                 rc = 0;
3118                         } else if (searchcqr->status == DASD_CQR_IN_ERP) {
3119                                 /*
3120                                  * Shouldn't happen; most recent ERP
3121                                  * request is at the front of queue
3122                                  */
3123                                 continue;
3124                         }
3125                         break;
3126                 }
3127                 spin_unlock(get_ccwdev_lock(device->cdev));
3128         }
3129         dasd_schedule_block_bh(block);
3130         spin_unlock(&block->queue_lock);
3131
3132         return rc ? BLK_EH_RESET_TIMER : BLK_EH_NOT_HANDLED;
3133 }
3134
3135 /*
3136  * Allocate and initialize request queue and default I/O scheduler.
3137  */
3138 static int dasd_alloc_queue(struct dasd_block *block)
3139 {
3140         block->request_queue = blk_init_queue(do_dasd_request,
3141                                                &block->request_queue_lock);
3142         if (block->request_queue == NULL)
3143                 return -ENOMEM;
3144
3145         block->request_queue->queuedata = block;
3146
3147         return 0;
3148 }
3149
3150 /*
3151  * Allocate and initialize request queue.
3152  */
3153 static void dasd_setup_queue(struct dasd_block *block)
3154 {
3155         struct request_queue *q = block->request_queue;
3156         int max;
3157
3158         if (block->base->features & DASD_FEATURE_USERAW) {
3159                 /*
3160                  * the max_blocks value for raw_track access is 256
3161                  * it is higher than the native ECKD value because we
3162                  * only need one ccw per track
3163                  * so the max_hw_sectors are
3164                  * 2048 x 512B = 1024kB = 16 tracks
3165                  */
3166                 max = 2048;
3167         } else {
3168                 max = block->base->discipline->max_blocks << block->s2b_shift;
3169         }
3170         queue_flag_set_unlocked(QUEUE_FLAG_NONROT, q);
3171         q->limits.max_dev_sectors = max;
3172         blk_queue_logical_block_size(q, block->bp_block);
3173         blk_queue_max_hw_sectors(q, max);
3174         blk_queue_max_segments(q, USHRT_MAX);
3175         /* with page sized segments we can translate each segement into
3176          * one idaw/tidaw
3177          */
3178         blk_queue_max_segment_size(q, PAGE_SIZE);
3179         blk_queue_segment_boundary(q, PAGE_SIZE - 1);
3180 }
3181
3182 /*
3183  * Deactivate and free request queue.
3184  */
3185 static void dasd_free_queue(struct dasd_block *block)
3186 {
3187         if (block->request_queue) {
3188                 blk_cleanup_queue(block->request_queue);
3189                 block->request_queue = NULL;
3190         }
3191 }
3192
3193 /*
3194  * Flush request on the request queue.
3195  */
3196 static void dasd_flush_request_queue(struct dasd_block *block)
3197 {
3198         struct request *req;
3199
3200         if (!block->request_queue)
3201                 return;
3202
3203         spin_lock_irq(&block->request_queue_lock);
3204         while ((req = blk_fetch_request(block->request_queue)))
3205                 __blk_end_request_all(req, BLK_STS_IOERR);
3206         spin_unlock_irq(&block->request_queue_lock);
3207 }
3208
3209 static int dasd_open(struct block_device *bdev, fmode_t mode)
3210 {
3211         struct dasd_device *base;
3212         int rc;
3213
3214         base = dasd_device_from_gendisk(bdev->bd_disk);
3215         if (!base)
3216                 return -ENODEV;
3217
3218         atomic_inc(&base->block->open_count);
3219         if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
3220                 rc = -ENODEV;
3221                 goto unlock;
3222         }
3223
3224         if (!try_module_get(base->discipline->owner)) {
3225                 rc = -EINVAL;
3226                 goto unlock;
3227         }
3228
3229         if (dasd_probeonly) {
3230                 dev_info(&base->cdev->dev,
3231                          "Accessing the DASD failed because it is in "
3232                          "probeonly mode\n");
3233                 rc = -EPERM;
3234                 goto out;
3235         }
3236
3237         if (base->state <= DASD_STATE_BASIC) {
3238                 DBF_DEV_EVENT(DBF_ERR, base, " %s",
3239                               " Cannot open unrecognized device");
3240                 rc = -ENODEV;
3241                 goto out;
3242         }
3243
3244         if ((mode & FMODE_WRITE) &&
3245             (test_bit(DASD_FLAG_DEVICE_RO, &base->flags) ||
3246              (base->features & DASD_FEATURE_READONLY))) {
3247                 rc = -EROFS;
3248                 goto out;
3249         }
3250
3251         dasd_put_device(base);
3252         return 0;
3253
3254 out:
3255         module_put(base->discipline->owner);
3256 unlock:
3257         atomic_dec(&base->block->open_count);
3258         dasd_put_device(base);
3259         return rc;
3260 }
3261
3262 static void dasd_release(struct gendisk *disk, fmode_t mode)
3263 {
3264         struct dasd_device *base = dasd_device_from_gendisk(disk);
3265         if (base) {
3266                 atomic_dec(&base->block->open_count);
3267                 module_put(base->discipline->owner);
3268                 dasd_put_device(base);
3269         }
3270 }
3271
3272 /*
3273  * Return disk geometry.
3274  */
3275 static int dasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
3276 {
3277         struct dasd_device *base;
3278
3279         base = dasd_device_from_gendisk(bdev->bd_disk);
3280         if (!base)
3281                 return -ENODEV;
3282
3283         if (!base->discipline ||
3284             !base->discipline->fill_geometry) {
3285                 dasd_put_device(base);
3286                 return -EINVAL;
3287         }
3288         base->discipline->fill_geometry(base->block, geo);
3289         geo->start = get_start_sect(bdev) >> base->block->s2b_shift;
3290         dasd_put_device(base);
3291         return 0;
3292 }
3293
3294 const struct block_device_operations
3295 dasd_device_operations = {
3296         .owner          = THIS_MODULE,
3297         .open           = dasd_open,
3298         .release        = dasd_release,
3299         .ioctl          = dasd_ioctl,
3300         .compat_ioctl   = dasd_ioctl,
3301         .getgeo         = dasd_getgeo,
3302 };
3303
3304 /*******************************************************************************
3305  * end of block device operations
3306  */
3307
3308 static void
3309 dasd_exit(void)
3310 {
3311 #ifdef CONFIG_PROC_FS
3312         dasd_proc_exit();
3313 #endif
3314         dasd_eer_exit();
3315         if (dasd_page_cache != NULL) {
3316                 kmem_cache_destroy(dasd_page_cache);
3317                 dasd_page_cache = NULL;
3318         }
3319         dasd_gendisk_exit();
3320         dasd_devmap_exit();
3321         if (dasd_debug_area != NULL) {
3322                 debug_unregister(dasd_debug_area);
3323                 dasd_debug_area = NULL;
3324         }
3325         dasd_statistics_removeroot();
3326 }
3327
3328 /*
3329  * SECTION: common functions for ccw_driver use
3330  */
3331
3332 /*
3333  * Is the device read-only?
3334  * Note that this function does not report the setting of the
3335  * readonly device attribute, but how it is configured in z/VM.
3336  */
3337 int dasd_device_is_ro(struct dasd_device *device)
3338 {
3339         struct ccw_dev_id dev_id;
3340         struct diag210 diag_data;
3341         int rc;
3342
3343         if (!MACHINE_IS_VM)
3344                 return 0;
3345         ccw_device_get_id(device->cdev, &dev_id);
3346         memset(&diag_data, 0, sizeof(diag_data));
3347         diag_data.vrdcdvno = dev_id.devno;
3348         diag_data.vrdclen = sizeof(diag_data);
3349         rc = diag210(&diag_data);
3350         if (rc == 0 || rc == 2) {
3351                 return diag_data.vrdcvfla & 0x80;
3352         } else {
3353                 DBF_EVENT(DBF_WARNING, "diag210 failed for dev=%04x with rc=%d",
3354                           dev_id.devno, rc);
3355                 return 0;
3356         }
3357 }
3358 EXPORT_SYMBOL_GPL(dasd_device_is_ro);
3359
3360 static void dasd_generic_auto_online(void *data, async_cookie_t cookie)
3361 {
3362         struct ccw_device *cdev = data;
3363         int ret;
3364
3365         ret = ccw_device_set_online(cdev);
3366         if (ret)
3367                 pr_warn("%s: Setting the DASD online failed with rc=%d\n",
3368                         dev_name(&cdev->dev), ret);
3369 }
3370
3371 /*
3372  * Initial attempt at a probe function. this can be simplified once
3373  * the other detection code is gone.
3374  */
3375 int dasd_generic_probe(struct ccw_device *cdev,
3376                        struct dasd_discipline *discipline)
3377 {
3378         int ret;
3379
3380         ret = dasd_add_sysfs_files(cdev);
3381         if (ret) {
3382                 DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s",
3383                                 "dasd_generic_probe: could not add "
3384                                 "sysfs entries");
3385                 return ret;
3386         }
3387         cdev->handler = &dasd_int_handler;
3388
3389         /*
3390          * Automatically online either all dasd devices (dasd_autodetect)
3391          * or all devices specified with dasd= parameters during
3392          * initial probe.
3393          */
3394         if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
3395             (dasd_autodetect && dasd_busid_known(dev_name(&cdev->dev)) != 0))
3396                 async_schedule(dasd_generic_auto_online, cdev);
3397         return 0;
3398 }
3399 EXPORT_SYMBOL_GPL(dasd_generic_probe);
3400
3401 void dasd_generic_free_discipline(struct dasd_device *device)
3402 {
3403         /* Forget the discipline information. */
3404         if (device->discipline) {
3405                 if (device->discipline->uncheck_device)
3406                         device->discipline->uncheck_device(device);
3407                 module_put(device->discipline->owner);
3408                 device->discipline = NULL;
3409         }
3410         if (device->base_discipline) {
3411                 module_put(device->base_discipline->owner);
3412                 device->base_discipline = NULL;
3413         }
3414 }
3415 EXPORT_SYMBOL_GPL(dasd_generic_free_discipline);
3416
3417 /*
3418  * This will one day be called from a global not_oper handler.
3419  * It is also used by driver_unregister during module unload.
3420  */
3421 void dasd_generic_remove(struct ccw_device *cdev)
3422 {
3423         struct dasd_device *device;
3424         struct dasd_block *block;
3425
3426         cdev->handler = NULL;
3427
3428         device = dasd_device_from_cdev(cdev);
3429         if (IS_ERR(device)) {
3430                 dasd_remove_sysfs_files(cdev);
3431                 return;
3432         }
3433         if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags) &&
3434             !test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3435                 /* Already doing offline processing */
3436                 dasd_put_device(device);
3437                 dasd_remove_sysfs_files(cdev);
3438                 return;
3439         }
3440         /*
3441          * This device is removed unconditionally. Set offline
3442          * flag to prevent dasd_open from opening it while it is
3443          * no quite down yet.
3444          */
3445         dasd_set_target_state(device, DASD_STATE_NEW);
3446         /* dasd_delete_device destroys the device reference. */
3447         block = device->block;
3448         dasd_delete_device(device);
3449         /*
3450          * life cycle of block is bound to device, so delete it after
3451          * device was safely removed
3452          */
3453         if (block)
3454                 dasd_free_block(block);
3455
3456         dasd_remove_sysfs_files(cdev);
3457 }
3458 EXPORT_SYMBOL_GPL(dasd_generic_remove);
3459
3460 /*
3461  * Activate a device. This is called from dasd_{eckd,fba}_probe() when either
3462  * the device is detected for the first time and is supposed to be used
3463  * or the user has started activation through sysfs.
3464  */
3465 int dasd_generic_set_online(struct ccw_device *cdev,
3466                             struct dasd_discipline *base_discipline)
3467 {
3468         struct dasd_discipline *discipline;
3469         struct dasd_device *device;
3470         int rc;
3471
3472         /* first online clears initial online feature flag */
3473         dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0);
3474         device = dasd_create_device(cdev);
3475         if (IS_ERR(device))
3476                 return PTR_ERR(device);
3477
3478         discipline = base_discipline;
3479         if (device->features & DASD_FEATURE_USEDIAG) {
3480                 if (!dasd_diag_discipline_pointer) {
3481                         /* Try to load the required module. */
3482                         rc = request_module(DASD_DIAG_MOD);
3483                         if (rc) {
3484                                 pr_warn("%s Setting the DASD online failed "
3485                                         "because the required module %s "
3486                                         "could not be loaded (rc=%d)\n",
3487                                         dev_name(&cdev->dev), DASD_DIAG_MOD,
3488                                         rc);
3489                                 dasd_delete_device(device);
3490                                 return -ENODEV;
3491                         }
3492                 }
3493                 /* Module init could have failed, so check again here after
3494                  * request_module(). */
3495                 if (!dasd_diag_discipline_pointer) {
3496                         pr_warn("%s Setting the DASD online failed because of missing DIAG discipline\n",
3497                                 dev_name(&cdev->dev));
3498                         dasd_delete_device(device);
3499                         return -ENODEV;
3500                 }
3501                 discipline = dasd_diag_discipline_pointer;
3502         }
3503         if (!try_module_get(base_discipline->owner)) {
3504                 dasd_delete_device(device);
3505                 return -EINVAL;
3506         }
3507         if (!try_module_get(discipline->owner)) {
3508                 module_put(base_discipline->owner);
3509                 dasd_delete_device(device);
3510                 return -EINVAL;
3511         }
3512         device->base_discipline = base_discipline;
3513         device->discipline = discipline;
3514
3515         /* check_device will allocate block device if necessary */
3516         rc = discipline->check_device(device);
3517         if (rc) {
3518                 pr_warn("%s Setting the DASD online with discipline %s failed with rc=%i\n",
3519                         dev_name(&cdev->dev), discipline->name, rc);
3520                 module_put(discipline->owner);
3521                 module_put(base_discipline->owner);
3522                 dasd_delete_device(device);
3523                 return rc;
3524         }
3525
3526         dasd_set_target_state(device, DASD_STATE_ONLINE);
3527         if (device->state <= DASD_STATE_KNOWN) {
3528                 pr_warn("%s Setting the DASD online failed because of a missing discipline\n",
3529                         dev_name(&cdev->dev));
3530                 rc = -ENODEV;
3531                 dasd_set_target_state(device, DASD_STATE_NEW);
3532                 if (device->block)
3533                         dasd_free_block(device->block);
3534                 dasd_delete_device(device);
3535         } else
3536                 pr_debug("dasd_generic device %s found\n",
3537                                 dev_name(&cdev->dev));
3538
3539         wait_event(dasd_init_waitq, _wait_for_device(device));
3540
3541         dasd_put_device(device);
3542         return rc;
3543 }
3544 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
3545
3546 int dasd_generic_set_offline(struct ccw_device *cdev)
3547 {
3548         struct dasd_device *device;
3549         struct dasd_block *block;
3550         int max_count, open_count, rc;
3551         unsigned long flags;
3552
3553         rc = 0;
3554         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
3555         device = dasd_device_from_cdev_locked(cdev);
3556         if (IS_ERR(device)) {
3557                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3558                 return PTR_ERR(device);
3559         }
3560
3561         /*
3562          * We must make sure that this device is currently not in use.
3563          * The open_count is increased for every opener, that includes
3564          * the blkdev_get in dasd_scan_partitions. We are only interested
3565          * in the other openers.
3566          */
3567         if (device->block) {
3568                 max_count = device->block->bdev ? 0 : -1;
3569                 open_count = atomic_read(&device->block->open_count);
3570                 if (open_count > max_count) {
3571                         if (open_count > 0)
3572                                 pr_warn("%s: The DASD cannot be set offline with open count %i\n",
3573                                         dev_name(&cdev->dev), open_count);
3574                         else
3575                                 pr_warn("%s: The DASD cannot be set offline while it is in use\n",
3576                                         dev_name(&cdev->dev));
3577                         rc = -EBUSY;
3578                         goto out_err;
3579                 }
3580         }
3581
3582         /*
3583          * Test if the offline processing is already running and exit if so.
3584          * If a safe offline is being processed this could only be a normal
3585          * offline that should be able to overtake the safe offline and
3586          * cancel any I/O we do not want to wait for any longer
3587          */
3588         if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
3589                 if (test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3590                         clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING,
3591                                   &device->flags);
3592                 } else {
3593                         rc = -EBUSY;
3594                         goto out_err;
3595                 }
3596         }
3597         set_bit(DASD_FLAG_OFFLINE, &device->flags);
3598
3599         /*
3600          * if safe_offline is called set safe_offline_running flag and
3601          * clear safe_offline so that a call to normal offline
3602          * can overrun safe_offline processing
3603          */
3604         if (test_and_clear_bit(DASD_FLAG_SAFE_OFFLINE, &device->flags) &&
3605             !test_and_set_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3606                 /* need to unlock here to wait for outstanding I/O */
3607                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3608                 /*
3609                  * If we want to set the device safe offline all IO operations
3610                  * should be finished before continuing the offline process
3611                  * so sync bdev first and then wait for our queues to become
3612                  * empty
3613                  */
3614                 if (device->block) {
3615                         rc = fsync_bdev(device->block->bdev);
3616                         if (rc != 0)
3617                                 goto interrupted;
3618                 }
3619                 dasd_schedule_device_bh(device);
3620                 rc = wait_event_interruptible(shutdown_waitq,
3621                                               _wait_for_empty_queues(device));
3622                 if (rc != 0)
3623                         goto interrupted;
3624
3625                 /*
3626                  * check if a normal offline process overtook the offline
3627                  * processing in this case simply do nothing beside returning
3628                  * that we got interrupted
3629                  * otherwise mark safe offline as not running any longer and
3630                  * continue with normal offline
3631                  */
3632                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
3633                 if (!test_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags)) {
3634                         rc = -ERESTARTSYS;
3635                         goto out_err;
3636                 }
3637                 clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags);
3638         }
3639         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3640
3641         dasd_set_target_state(device, DASD_STATE_NEW);
3642         /* dasd_delete_device destroys the device reference. */
3643         block = device->block;
3644         dasd_delete_device(device);
3645         /*
3646          * life cycle of block is bound to device, so delete it after
3647          * device was safely removed
3648          */
3649         if (block)
3650                 dasd_free_block(block);
3651
3652         return 0;
3653
3654 interrupted:
3655         /* interrupted by signal */
3656         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
3657         clear_bit(DASD_FLAG_SAFE_OFFLINE_RUNNING, &device->flags);
3658         clear_bit(DASD_FLAG_OFFLINE, &device->flags);
3659 out_err:
3660         dasd_put_device(device);
3661         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
3662         return rc;
3663 }
3664 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
3665
3666 int dasd_generic_last_path_gone(struct dasd_device *device)
3667 {
3668         struct dasd_ccw_req *cqr;
3669
3670         dev_warn(&device->cdev->dev, "No operational channel path is left "
3671                  "for the device\n");
3672         DBF_DEV_EVENT(DBF_WARNING, device, "%s", "last path gone");
3673         /* First of all call extended error reporting. */
3674         dasd_eer_write(device, NULL, DASD_EER_NOPATH);
3675
3676         if (device->state < DASD_STATE_BASIC)
3677                 return 0;
3678         /* Device is active. We want to keep it. */
3679         list_for_each_entry(cqr, &device->ccw_queue, devlist)
3680                 if ((cqr->status == DASD_CQR_IN_IO) ||
3681                     (cqr->status == DASD_CQR_CLEAR_PENDING)) {
3682                         cqr->status = DASD_CQR_QUEUED;
3683                         cqr->retries++;
3684                 }
3685         dasd_device_set_stop_bits(device, DASD_STOPPED_DC_WAIT);
3686         dasd_device_clear_timer(device);
3687         dasd_schedule_device_bh(device);
3688         return 1;
3689 }
3690 EXPORT_SYMBOL_GPL(dasd_generic_last_path_gone);
3691
3692 int dasd_generic_path_operational(struct dasd_device *device)
3693 {
3694         dev_info(&device->cdev->dev, "A channel path to the device has become "
3695                  "operational\n");
3696         DBF_DEV_EVENT(DBF_WARNING, device, "%s", "path operational");
3697         dasd_device_remove_stop_bits(device, DASD_STOPPED_DC_WAIT);
3698         if (device->stopped & DASD_UNRESUMED_PM) {
3699                 dasd_device_remove_stop_bits(device, DASD_UNRESUMED_PM);
3700                 dasd_restore_device(device);
3701                 return 1;
3702         }
3703         dasd_schedule_device_bh(device);
3704         if (device->block)
3705                 dasd_schedule_block_bh(device->block);
3706
3707         if (!device->stopped)
3708                 wake_up(&generic_waitq);
3709
3710         return 1;
3711 }
3712 EXPORT_SYMBOL_GPL(dasd_generic_path_operational);
3713
3714 int dasd_generic_notify(struct ccw_device *cdev, int event)
3715 {
3716         struct dasd_device *device;
3717         int ret;
3718
3719         device = dasd_device_from_cdev_locked(cdev);
3720         if (IS_ERR(device))
3721                 return 0;
3722         ret = 0;
3723         switch (event) {
3724         case CIO_GONE:
3725         case CIO_BOXED:
3726         case CIO_NO_PATH:
3727                 dasd_path_no_path(device);
3728                 ret = dasd_generic_last_path_gone(device);
3729                 break;
3730         case CIO_OPER:
3731                 ret = 1;
3732                 if (dasd_path_get_opm(device))
3733                         ret = dasd_generic_path_operational(device);
3734                 break;
3735         }
3736         dasd_put_device(device);
3737         return ret;
3738 }
3739 EXPORT_SYMBOL_GPL(dasd_generic_notify);
3740
3741 void dasd_generic_path_event(struct ccw_device *cdev, int *path_event)
3742 {
3743         struct dasd_device *device;
3744         int chp, oldopm, hpfpm, ifccpm;
3745
3746         device = dasd_device_from_cdev_locked(cdev);
3747         if (IS_ERR(device))
3748                 return;
3749
3750         oldopm = dasd_path_get_opm(device);
3751         for (chp = 0; chp < 8; chp++) {
3752                 if (path_event[chp] & PE_PATH_GONE) {
3753                         dasd_path_notoper(device, chp);
3754                 }
3755                 if (path_event[chp] & PE_PATH_AVAILABLE) {
3756                         dasd_path_available(device, chp);
3757                         dasd_schedule_device_bh(device);
3758                 }
3759                 if (path_event[chp] & PE_PATHGROUP_ESTABLISHED) {
3760                         if (!dasd_path_is_operational(device, chp) &&
3761                             !dasd_path_need_verify(device, chp)) {
3762                                 /*
3763                                  * we can not establish a pathgroup on an
3764                                  * unavailable path, so trigger a path
3765                                  * verification first
3766                                  */
3767                         dasd_path_available(device, chp);
3768                         dasd_schedule_device_bh(device);
3769                         }
3770                         DBF_DEV_EVENT(DBF_WARNING, device, "%s",
3771                                       "Pathgroup re-established\n");
3772                         if (device->discipline->kick_validate)
3773                                 device->discipline->kick_validate(device);
3774                 }
3775         }
3776         hpfpm = dasd_path_get_hpfpm(device);
3777         ifccpm = dasd_path_get_ifccpm(device);
3778         if (!dasd_path_get_opm(device) && hpfpm) {
3779                 /*
3780                  * device has no operational paths but at least one path is
3781                  * disabled due to HPF errors
3782                  * disable HPF at all and use the path(s) again
3783                  */
3784                 if (device->discipline->disable_hpf)
3785                         device->discipline->disable_hpf(device);
3786                 dasd_device_set_stop_bits(device, DASD_STOPPED_NOT_ACC);
3787                 dasd_path_set_tbvpm(device, hpfpm);
3788                 dasd_schedule_device_bh(device);
3789                 dasd_schedule_requeue(device);
3790         } else if (!dasd_path_get_opm(device) && ifccpm) {
3791                 /*
3792                  * device has no operational paths but at least one path is
3793                  * disabled due to IFCC errors
3794                  * trigger path verification on paths with IFCC errors
3795                  */
3796                 dasd_path_set_tbvpm(device, ifccpm);
3797                 dasd_schedule_device_bh(device);
3798         }
3799         if (oldopm && !dasd_path_get_opm(device) && !hpfpm && !ifccpm) {
3800                 dev_warn(&device->cdev->dev,
3801                          "No verified channel paths remain for the device\n");
3802                 DBF_DEV_EVENT(DBF_WARNING, device,
3803                               "%s", "last verified path gone");
3804                 dasd_eer_write(device, NULL, DASD_EER_NOPATH);
3805                 dasd_device_set_stop_bits(device,
3806                                           DASD_STOPPED_DC_WAIT);
3807         }
3808         dasd_put_device(device);
3809 }
3810 EXPORT_SYMBOL_GPL(dasd_generic_path_event);
3811
3812 int dasd_generic_verify_path(struct dasd_device *device, __u8 lpm)
3813 {
3814         if (!dasd_path_get_opm(device) && lpm) {
3815                 dasd_path_set_opm(device, lpm);
3816                 dasd_generic_path_operational(device);
3817         } else
3818                 dasd_path_add_opm(device, lpm);
3819         return 0;
3820 }
3821 EXPORT_SYMBOL_GPL(dasd_generic_verify_path);
3822
3823 /*
3824  * clear active requests and requeue them to block layer if possible
3825  */
3826 static int dasd_generic_requeue_all_requests(struct dasd_device *device)
3827 {
3828         struct list_head requeue_queue;
3829         struct dasd_ccw_req *cqr, *n;
3830         struct dasd_ccw_req *refers;
3831         int rc;
3832
3833         INIT_LIST_HEAD(&requeue_queue);
3834         spin_lock_irq(get_ccwdev_lock(device->cdev));
3835         rc = 0;
3836         list_for_each_entry_safe(cqr, n, &device->ccw_queue, devlist) {
3837                 /* Check status and move request to flush_queue */
3838                 if (cqr->status == DASD_CQR_IN_IO) {
3839                         rc = device->discipline->term_IO(cqr);
3840                         if (rc) {
3841                                 /* unable to terminate requeust */
3842                                 dev_err(&device->cdev->dev,
3843                                         "Unable to terminate request %p "
3844                                         "on suspend\n", cqr);
3845                                 spin_unlock_irq(get_ccwdev_lock(device->cdev));
3846                                 dasd_put_device(device);
3847                                 return rc;
3848                         }
3849                 }
3850                 list_move_tail(&cqr->devlist, &requeue_queue);
3851         }
3852         spin_unlock_irq(get_ccwdev_lock(device->cdev));
3853
3854         list_for_each_entry_safe(cqr, n, &requeue_queue, devlist) {
3855                 wait_event(dasd_flush_wq,
3856                            (cqr->status != DASD_CQR_CLEAR_PENDING));
3857
3858                 /* mark sleepon requests as ended */
3859                 if (cqr->callback_data == DASD_SLEEPON_START_TAG)
3860                         cqr->callback_data = DASD_SLEEPON_END_TAG;
3861
3862                 /* remove requests from device and block queue */
3863                 list_del_init(&cqr->devlist);
3864                 while (cqr->refers != NULL) {
3865                         refers = cqr->refers;
3866                         /* remove the request from the block queue */
3867                         list_del(&cqr->blocklist);
3868                         /* free the finished erp request */
3869                         dasd_free_erp_request(cqr, cqr->memdev);
3870                         cqr = refers;
3871                 }
3872
3873                 /*
3874                  * requeue requests to blocklayer will only work
3875                  * for block device requests
3876                  */
3877                 if (_dasd_requeue_request(cqr))
3878                         continue;
3879
3880                 if (cqr->block)
3881                         list_del_init(&cqr->blocklist);
3882                 cqr->block->base->discipline->free_cp(
3883                         cqr, (struct request *) cqr->callback_data);
3884         }
3885
3886         /*
3887          * if requests remain then they are internal request
3888          * and go back to the device queue
3889          */
3890         if (!list_empty(&requeue_queue)) {
3891                 /* move freeze_queue to start of the ccw_queue */
3892                 spin_lock_irq(get_ccwdev_lock(device->cdev));
3893                 list_splice_tail(&requeue_queue, &device->ccw_queue);
3894                 spin_unlock_irq(get_ccwdev_lock(device->cdev));
3895         }
3896         /* wake up generic waitqueue for eventually ended sleepon requests */
3897         wake_up(&generic_waitq);
3898         return rc;
3899 }
3900
3901 static void do_requeue_requests(struct work_struct *work)
3902 {
3903         struct dasd_device *device = container_of(work, struct dasd_device,
3904                                                   requeue_requests);
3905         dasd_generic_requeue_all_requests(device);
3906         dasd_device_remove_stop_bits(device, DASD_STOPPED_NOT_ACC);
3907         if (device->block)
3908                 dasd_schedule_block_bh(device->block);
3909         dasd_put_device(device);
3910 }
3911
3912 void dasd_schedule_requeue(struct dasd_device *device)
3913 {
3914         dasd_get_device(device);
3915         /* queue call to dasd_reload_device to the kernel event daemon. */
3916         if (!schedule_work(&device->requeue_requests))
3917                 dasd_put_device(device);
3918 }
3919 EXPORT_SYMBOL(dasd_schedule_requeue);
3920
3921 int dasd_generic_pm_freeze(struct ccw_device *cdev)
3922 {
3923         struct dasd_device *device = dasd_device_from_cdev(cdev);
3924         int rc;
3925
3926         if (IS_ERR(device))
3927                 return PTR_ERR(device);
3928
3929         /* mark device as suspended */
3930         set_bit(DASD_FLAG_SUSPENDED, &device->flags);
3931
3932         if (device->discipline->freeze)
3933                 rc = device->discipline->freeze(device);
3934
3935         /* disallow new I/O  */
3936         dasd_device_set_stop_bits(device, DASD_STOPPED_PM);
3937
3938         return dasd_generic_requeue_all_requests(device);
3939 }
3940 EXPORT_SYMBOL_GPL(dasd_generic_pm_freeze);
3941
3942 int dasd_generic_restore_device(struct ccw_device *cdev)
3943 {
3944         struct dasd_device *device = dasd_device_from_cdev(cdev);
3945         int rc = 0;
3946
3947         if (IS_ERR(device))
3948                 return PTR_ERR(device);
3949
3950         /* allow new IO again */
3951         dasd_device_remove_stop_bits(device,
3952                                      (DASD_STOPPED_PM | DASD_UNRESUMED_PM));
3953
3954         dasd_schedule_device_bh(device);
3955
3956         /*
3957          * call discipline restore function
3958          * if device is stopped do nothing e.g. for disconnected devices
3959          */
3960         if (device->discipline->restore && !(device->stopped))
3961                 rc = device->discipline->restore(device);
3962         if (rc || device->stopped)
3963                 /*
3964                  * if the resume failed for the DASD we put it in
3965                  * an UNRESUMED stop state
3966                  */
3967                 device->stopped |= DASD_UNRESUMED_PM;
3968
3969         if (device->block)
3970                 dasd_schedule_block_bh(device->block);
3971
3972         clear_bit(DASD_FLAG_SUSPENDED, &device->flags);
3973         dasd_put_device(device);
3974         return 0;
3975 }
3976 EXPORT_SYMBOL_GPL(dasd_generic_restore_device);
3977
3978 static struct dasd_ccw_req *dasd_generic_build_rdc(struct dasd_device *device,
3979                                                    void *rdc_buffer,
3980                                                    int rdc_buffer_size,
3981                                                    int magic)
3982 {
3983         struct dasd_ccw_req *cqr;
3984         struct ccw1 *ccw;
3985         unsigned long *idaw;
3986
3987         cqr = dasd_smalloc_request(magic, 1 /* RDC */, rdc_buffer_size, device);
3988
3989         if (IS_ERR(cqr)) {
3990                 /* internal error 13 - Allocating the RDC request failed*/
3991                 dev_err(&device->cdev->dev,
3992                          "An error occurred in the DASD device driver, "
3993                          "reason=%s\n", "13");
3994                 return cqr;
3995         }
3996
3997         ccw = cqr->cpaddr;
3998         ccw->cmd_code = CCW_CMD_RDC;
3999         if (idal_is_needed(rdc_buffer, rdc_buffer_size)) {
4000                 idaw = (unsigned long *) (cqr->data);
4001                 ccw->cda = (__u32)(addr_t) idaw;
4002                 ccw->flags = CCW_FLAG_IDA;
4003                 idaw = idal_create_words(idaw, rdc_buffer, rdc_buffer_size);
4004         } else {
4005                 ccw->cda = (__u32)(addr_t) rdc_buffer;
4006                 ccw->flags = 0;
4007         }
4008
4009         ccw->count = rdc_buffer_size;
4010         cqr->startdev = device;
4011         cqr->memdev = device;
4012         cqr->expires = 10*HZ;
4013         cqr->retries = 256;
4014         cqr->buildclk = get_tod_clock();
4015         cqr->status = DASD_CQR_FILLED;
4016         return cqr;
4017 }
4018
4019
4020 int dasd_generic_read_dev_chars(struct dasd_device *device, int magic,
4021                                 void *rdc_buffer, int rdc_buffer_size)
4022 {
4023         int ret;
4024         struct dasd_ccw_req *cqr;
4025
4026         cqr = dasd_generic_build_rdc(device, rdc_buffer, rdc_buffer_size,
4027                                      magic);
4028         if (IS_ERR(cqr))
4029                 return PTR_ERR(cqr);
4030
4031         ret = dasd_sleep_on(cqr);
4032         dasd_sfree_request(cqr, cqr->memdev);
4033         return ret;
4034 }
4035 EXPORT_SYMBOL_GPL(dasd_generic_read_dev_chars);
4036
4037 /*
4038  *   In command mode and transport mode we need to look for sense
4039  *   data in different places. The sense data itself is allways
4040  *   an array of 32 bytes, so we can unify the sense data access
4041  *   for both modes.
4042  */
4043 char *dasd_get_sense(struct irb *irb)
4044 {
4045         struct tsb *tsb = NULL;
4046         char *sense = NULL;
4047
4048         if (scsw_is_tm(&irb->scsw) && (irb->scsw.tm.fcxs == 0x01)) {
4049                 if (irb->scsw.tm.tcw)
4050                         tsb = tcw_get_tsb((struct tcw *)(unsigned long)
4051                                           irb->scsw.tm.tcw);
4052                 if (tsb && tsb->length == 64 && tsb->flags)
4053                         switch (tsb->flags & 0x07) {
4054                         case 1: /* tsa_iostat */
4055                                 sense = tsb->tsa.iostat.sense;
4056                                 break;
4057                         case 2: /* tsa_ddpc */
4058                                 sense = tsb->tsa.ddpc.sense;
4059                                 break;
4060                         default:
4061                                 /* currently we don't use interrogate data */
4062                                 break;
4063                         }
4064         } else if (irb->esw.esw0.erw.cons) {
4065                 sense = irb->ecw;
4066         }
4067         return sense;
4068 }
4069 EXPORT_SYMBOL_GPL(dasd_get_sense);
4070
4071 void dasd_generic_shutdown(struct ccw_device *cdev)
4072 {
4073         struct dasd_device *device;
4074
4075         device = dasd_device_from_cdev(cdev);
4076         if (IS_ERR(device))
4077                 return;
4078
4079         if (device->block)
4080                 dasd_schedule_block_bh(device->block);
4081
4082         dasd_schedule_device_bh(device);
4083
4084         wait_event(shutdown_waitq, _wait_for_empty_queues(device));
4085 }
4086 EXPORT_SYMBOL_GPL(dasd_generic_shutdown);
4087
4088 static int __init dasd_init(void)
4089 {
4090         int rc;
4091
4092         init_waitqueue_head(&dasd_init_waitq);
4093         init_waitqueue_head(&dasd_flush_wq);
4094         init_waitqueue_head(&generic_waitq);
4095         init_waitqueue_head(&shutdown_waitq);
4096
4097         /* register 'common' DASD debug area, used for all DBF_XXX calls */
4098         dasd_debug_area = debug_register("dasd", 1, 1, 8 * sizeof(long));
4099         if (dasd_debug_area == NULL) {
4100                 rc = -ENOMEM;
4101                 goto failed;
4102         }
4103         debug_register_view(dasd_debug_area, &debug_sprintf_view);
4104         debug_set_level(dasd_debug_area, DBF_WARNING);
4105
4106         DBF_EVENT(DBF_EMERG, "%s", "debug area created");
4107
4108         dasd_diag_discipline_pointer = NULL;
4109
4110         dasd_statistics_createroot();
4111
4112         rc = dasd_devmap_init();
4113         if (rc)
4114                 goto failed;
4115         rc = dasd_gendisk_init();
4116         if (rc)
4117                 goto failed;
4118         rc = dasd_parse();
4119         if (rc)
4120                 goto failed;
4121         rc = dasd_eer_init();
4122         if (rc)
4123                 goto failed;
4124 #ifdef CONFIG_PROC_FS
4125         rc = dasd_proc_init();
4126         if (rc)
4127                 goto failed;
4128 #endif
4129
4130         return 0;
4131 failed:
4132         pr_info("The DASD device driver could not be initialized\n");
4133         dasd_exit();
4134         return rc;
4135 }
4136
4137 module_init(dasd_init);
4138 module_exit(dasd_exit);