drivers/s390/block/dasd.c

   1 /*
   2  * File...........: linux/drivers/s390/block/dasd.c
   3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
   4  *                  Horst Hummel <Horst.Hummel@de.ibm.com>
   5  *                  Carsten Otte <Cotte@de.ibm.com>
   6  *                  Martin Schwidefsky <schwidefsky@de.ibm.com>
   7  * Bugreports.to..: <Linux390@de.ibm.com>
   8  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999-2001
   9  *
  10  * $Revision: 1.142 $
  11  */
  12
  13 #include <linux/config.h>
  14 #include <linux/kmod.h>
  15 #include <linux/init.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/ctype.h>
  18 #include <linux/major.h>
  19 #include <linux/slab.h>
  20 #include <linux/buffer_head.h>
  21
  22 #include <asm/ccwdev.h>
  23 #include <asm/ebcdic.h>
  24 #include <asm/idals.h>
  25 #include <asm/todclk.h>
  26
  27 /* This is ugly... */
  28 #define PRINTK_HEADER "dasd:"
  29
  30 #include "dasd_int.h"
  31 /*
  32  * SECTION: Constant definitions to be used within this file
  33  */
  34 #define DASD_CHANQ_MAX_SIZE 4
  35
  36 /*
  37  * SECTION: exported variables of dasd.c
  38  */
  39 debug_info_t *dasd_debug_area;
  40 struct dasd_discipline *dasd_diag_discipline_pointer;
  41
  42 MODULE_AUTHOR("Holger Smolinski <Holger.Smolinski@de.ibm.com>");
  43 MODULE_DESCRIPTION("Linux on S/390 DASD device driver,"
  44                    " Copyright 2000 IBM Corporation");
  45 MODULE_SUPPORTED_DEVICE("dasd");
  46 MODULE_PARM(dasd, "1-" __MODULE_STRING(256) "s");
  47 MODULE_LICENSE("GPL");
  48
  49 /*
  50  * SECTION: prototypes for static functions of dasd.c
  51  */
  52 static int  dasd_alloc_queue(struct dasd_device * device);
  53 static void dasd_setup_queue(struct dasd_device * device);
  54 static void dasd_free_queue(struct dasd_device * device);
  55 static void dasd_flush_request_queue(struct dasd_device *);
  56 static void dasd_int_handler(struct ccw_device *, unsigned long, struct irb *);
  57 static void dasd_flush_ccw_queue(struct dasd_device *, int);
  58 static void dasd_tasklet(struct dasd_device *);
  59 static void do_kick_device(void *data);
  60
  61 /*
  62  * SECTION: Operations on the device structure.
  63  */
  64 static wait_queue_head_t dasd_init_waitq;
  65
  66 /*
  67  * Allocate memory for a new device structure.
  68  */
  69 struct dasd_device *
  70 dasd_alloc_device(void)
  71 {
  72         struct dasd_device *device;
  73
  74         device = kmalloc(sizeof (struct dasd_device), GFP_ATOMIC);
  75         if (device == NULL)
  76                 return ERR_PTR(-ENOMEM);
  77         memset(device, 0, sizeof (struct dasd_device));
  78         /* open_count = 0 means device online but not in use */
  79         atomic_set(&device->open_count, -1);
  80
  81         /* Get two pages for normal block device operations. */
  82         device->ccw_mem = (void *) __get_free_pages(GFP_ATOMIC | GFP_DMA, 1);
  83         if (device->ccw_mem == NULL) {
  84                 kfree(device);
  85                 return ERR_PTR(-ENOMEM);
  86         }
  87         /* Get one page for error recovery. */
  88         device->erp_mem = (void *) get_zeroed_page(GFP_ATOMIC | GFP_DMA);
  89         if (device->erp_mem == NULL) {
  90                 free_pages((unsigned long) device->ccw_mem, 1);
  91                 kfree(device);
  92                 return ERR_PTR(-ENOMEM);
  93         }
  94
  95         dasd_init_chunklist(&device->ccw_chunks, device->ccw_mem, PAGE_SIZE*2);
  96         dasd_init_chunklist(&device->erp_chunks, device->erp_mem, PAGE_SIZE);
  97         spin_lock_init(&device->mem_lock);
  98         spin_lock_init(&device->request_queue_lock);
  99         atomic_set (&device->tasklet_scheduled, 0);
 100         tasklet_init(&device->tasklet,
 101                      (void (*)(unsigned long)) dasd_tasklet,
 102                      (unsigned long) device);
 103         INIT_LIST_HEAD(&device->ccw_queue);
 104         init_timer(&device->timer);
 105         INIT_WORK(&device->kick_work, do_kick_device, device);
 106         device->state = DASD_STATE_NEW;
 107         device->target = DASD_STATE_NEW;
 108
 109         return device;
 110 }
 111
 112 /*
 113  * Free memory of a device structure.
 114  */
 115 void
 116 dasd_free_device(struct dasd_device *device)
 117 {
 118         if (device->private)
 119                 kfree(device->private);
 120         free_page((unsigned long) device->erp_mem);
 121         free_pages((unsigned long) device->ccw_mem, 1);
 122         kfree(device);
 123 }
 124
 125 /*
 126  * Make a new device known to the system.
 127  */
 128 static inline int
 129 dasd_state_new_to_known(struct dasd_device *device)
 130 {
 131         int rc;
 132
 133         /*
 134          * As long as the device is not in state DASD_STATE_NEW we want to
 135          * keep the reference count > 0.
 136          */
 137         dasd_get_device(device);
 138
 139         rc = dasd_alloc_queue(device);
 140         if (rc) {
 141                 dasd_put_device(device);
 142                 return rc;
 143         }
 144
 145         device->state = DASD_STATE_KNOWN;
 146         return 0;
 147 }
 148
 149 /*
 150  * Let the system forget about a device.
 151  */
 152 static inline void
 153 dasd_state_known_to_new(struct dasd_device * device)
 154 {
 155         /* Forget the discipline information. */
 156         device->discipline = NULL;
 157         device->state = DASD_STATE_NEW;
 158
 159         dasd_free_queue(device);
 160
 161         /* Give up reference we took in dasd_state_new_to_known. */
 162         dasd_put_device(device);
 163 }
 164
 165 /*
 166  * Request the irq line for the device.
 167  */
 168 static inline int
 169 dasd_state_known_to_basic(struct dasd_device * device)
 170 {
 171         int rc;
 172
 173         /* Allocate and register gendisk structure. */
 174         rc = dasd_gendisk_alloc(device);
 175         if (rc)
 176                 return rc;
 177
 178         /* register 'device' debug area, used for all DBF_DEV_XXX calls */
 179         device->debug_area = debug_register(device->cdev->dev.bus_id, 0, 2,
 180                                             8 * sizeof (long));
 181         debug_register_view(device->debug_area, &debug_sprintf_view);
 182         debug_set_level(device->debug_area, DBF_ERR);
 183         DBF_DEV_EVENT(DBF_EMERG, device, "%s", "debug area created");
 184
 185         device->state = DASD_STATE_BASIC;
 186         return 0;
 187 }
 188
 189 /*
 190  * Release the irq line for the device. Terminate any running i/o.
 191  */
 192 static inline void
 193 dasd_state_basic_to_known(struct dasd_device * device)
 194 {
 195         dasd_gendisk_free(device);
 196         dasd_flush_ccw_queue(device, 1);
 197         DBF_DEV_EVENT(DBF_EMERG, device, "%p debug area deleted", device);
 198         if (device->debug_area != NULL) {
 199                 debug_unregister(device->debug_area);
 200                 device->debug_area = NULL;
 201         }
 202         device->state = DASD_STATE_KNOWN;
 203 }
 204
 205 /*
 206  * Do the initial analysis. The do_analysis function may return
 207  * -EAGAIN in which case the device keeps the state DASD_STATE_BASIC
 208  * until the discipline decides to continue the startup sequence
 209  * by calling the function dasd_change_state. The eckd disciplines
 210  * uses this to start a ccw that detects the format. The completion
 211  * interrupt for this detection ccw uses the kernel event daemon to
 212  * trigger the call to dasd_change_state. All this is done in the
 213  * discipline code, see dasd_eckd.c.
 214  * After the analysis ccw is done (do_analysis returned 0 or error)
 215  * the block device is setup. Either a fake disk is added to allow
 216  * formatting or a proper device request queue is created.
 217  */
 218 static inline int
 219 dasd_state_basic_to_ready(struct dasd_device * device)
 220 {
 221         int rc;
 222
 223         rc = 0;
 224         if (device->discipline->do_analysis != NULL)
 225                 rc = device->discipline->do_analysis(device);
 226         if (rc)
 227                 return rc;
 228         dasd_setup_queue(device);
 229         device->state = DASD_STATE_READY;
 230         if (dasd_scan_partitions(device) != 0)
 231                 device->state = DASD_STATE_BASIC;
 232         return 0;
 233 }
 234
 235 /*
 236  * Remove device from block device layer. Destroy dirty buffers.
 237  * Forget format information. Check if the target level is basic
 238  * and if it is create fake disk for formatting.
 239  */
 240 static inline void
 241 dasd_state_ready_to_basic(struct dasd_device * device)
 242 {
 243         dasd_flush_ccw_queue(device, 0);
 244         dasd_destroy_partitions(device);
 245         dasd_flush_request_queue(device);
 246         device->blocks = 0;
 247         device->bp_block = 0;
 248         device->s2b_shift = 0;
 249         device->state = DASD_STATE_BASIC;
 250 }
 251
 252 /*
 253  * Make the device online and schedule the bottom half to start
 254  * the requeueing of requests from the linux request queue to the
 255  * ccw queue.
 256  */
 257 static inline int
 258 dasd_state_ready_to_online(struct dasd_device * device)
 259 {
 260         device->state = DASD_STATE_ONLINE;
 261         dasd_schedule_bh(device);
 262         return 0;
 263 }
 264
 265 /*
 266  * Stop the requeueing of requests again.
 267  */
 268 static inline void
 269 dasd_state_online_to_ready(struct dasd_device * device)
 270 {
 271         device->state = DASD_STATE_READY;
 272 }
 273
 274 /*
 275  * Device startup state changes.
 276  */
 277 static inline int
 278 dasd_increase_state(struct dasd_device *device)
 279 {
 280         int rc;
 281
 282         rc = 0;
 283         if (device->state == DASD_STATE_NEW &&
 284             device->target >= DASD_STATE_KNOWN)
 285                 rc = dasd_state_new_to_known(device);
 286
 287         if (!rc &&
 288             device->state == DASD_STATE_KNOWN &&
 289             device->target >= DASD_STATE_BASIC)
 290                 rc = dasd_state_known_to_basic(device);
 291
 292         if (!rc &&
 293             device->state == DASD_STATE_BASIC &&
 294             device->target >= DASD_STATE_READY)
 295                 rc = dasd_state_basic_to_ready(device);
 296
 297         if (!rc &&
 298             device->state == DASD_STATE_READY &&
 299             device->target >= DASD_STATE_ONLINE)
 300                 rc = dasd_state_ready_to_online(device);
 301
 302         return rc;
 303 }
 304
 305 /*
 306  * Device shutdown state changes.
 307  */
 308 static inline int
 309 dasd_decrease_state(struct dasd_device *device)
 310 {
 311         if (device->state == DASD_STATE_ONLINE &&
 312             device->target <= DASD_STATE_READY)
 313                 dasd_state_online_to_ready(device);
 314
 315         if (device->state == DASD_STATE_READY &&
 316             device->target <= DASD_STATE_BASIC)
 317                 dasd_state_ready_to_basic(device);
 318
 319         if (device->state == DASD_STATE_BASIC &&
 320             device->target <= DASD_STATE_KNOWN)
 321                 dasd_state_basic_to_known(device);
 322
 323         if (device->state == DASD_STATE_KNOWN &&
 324             device->target <= DASD_STATE_NEW)
 325                 dasd_state_known_to_new(device);
 326
 327         return 0;
 328 }
 329
 330 /*
 331  * This is the main startup/shutdown routine.
 332  */
 333 static void
 334 dasd_change_state(struct dasd_device *device)
 335 {
 336         int rc;
 337
 338         if (device->state == device->target)
 339                 /* Already where we want to go today... */
 340                 return;
 341         if (device->state < device->target)
 342                 rc = dasd_increase_state(device);
 343         else
 344                 rc = dasd_decrease_state(device);
 345         if (rc && rc != -EAGAIN)
 346                 device->target = device->state;
 347
 348         if (device->state == device->target)
 349                 wake_up(&dasd_init_waitq);
 350 }
 351
 352 /*
 353  * Kick starter for devices that did not complete the startup/shutdown
 354  * procedure or were sleeping because of a pending state.
 355  * dasd_kick_device will schedule a call do do_kick_device to the kernel
 356  * event daemon.
 357  */
 358 static void
 359 do_kick_device(void *data)
 360 {
 361         struct dasd_device *device;
 362
 363         device = (struct dasd_device *) data;
 364         dasd_change_state(device);
 365         dasd_schedule_bh(device);
 366         dasd_put_device(device);
 367 }
 368
 369 void
 370 dasd_kick_device(struct dasd_device *device)
 371 {
 372         dasd_get_device(device);
 373         /* queue call to dasd_kick_device to the kernel event daemon. */
 374         schedule_work(&device->kick_work);
 375 }
 376
 377 /*
 378  * Set the target state for a device and starts the state change.
 379  */
 380 void
 381 dasd_set_target_state(struct dasd_device *device, int target)
 382 {
 383         /* If we are in probeonly mode stop at DASD_STATE_READY. */
 384         if (dasd_probeonly && target > DASD_STATE_READY)
 385                 target = DASD_STATE_READY;
 386         if (device->target != target) {
 387                 if (device->state == target)
 388                         wake_up(&dasd_init_waitq);
 389                 device->target = target;
 390         }
 391         if (device->state != device->target)
 392                 dasd_change_state(device);
 393 }
 394
 395 /*
 396  * Enable devices with device numbers in [from..to].
 397  */
 398 static inline int
 399 _wait_for_device(struct dasd_device *device)
 400 {
 401         return (device->state == device->target);
 402 }
 403
 404 void
 405 dasd_enable_device(struct dasd_device *device)
 406 {
 407         dasd_set_target_state(device, DASD_STATE_ONLINE);
 408         if (device->state <= DASD_STATE_KNOWN)
 409                 /* No discipline for device found. */
 410                 dasd_set_target_state(device, DASD_STATE_NEW);
 411         /* Now wait for the devices to come up. */
 412         wait_event(dasd_init_waitq, _wait_for_device(device));
 413 }
 414
 415 /*
 416  * SECTION: device operation (interrupt handler, start i/o, term i/o ...)
 417  */
 418 #ifdef CONFIG_DASD_PROFILE
 419
 420 struct dasd_profile_info_t dasd_global_profile;
 421 unsigned int dasd_profile_level = DASD_PROFILE_OFF;
 422
 423 /*
 424  * Increments counter in global and local profiling structures.
 425  */
 426 #define dasd_profile_counter(value, counter, device) \
 427 { \
 428         int index; \
 429         for (index = 0; index < 31 && value >> (2+index); index++); \
 430         dasd_global_profile.counter[index]++; \
 431         device->profile.counter[index]++; \
 432 }
 433
 434 /*
 435  * Add profiling information for cqr before execution.
 436  */
 437 static inline void
 438 dasd_profile_start(struct dasd_device *device, struct dasd_ccw_req * cqr,
 439                    struct request *req)
 440 {
 441         struct list_head *l;
 442         unsigned int counter;
 443
 444         if (dasd_profile_level != DASD_PROFILE_ON)
 445                 return;
 446
 447         /* count the length of the chanq for statistics */
 448         counter = 0;
 449         list_for_each(l, &device->ccw_queue)
 450                 if (++counter >= 31)
 451                         break;
 452         dasd_global_profile.dasd_io_nr_req[counter]++;
 453         device->profile.dasd_io_nr_req[counter]++;
 454 }
 455
 456 /*
 457  * Add profiling information for cqr after execution.
 458  */
 459 static inline void
 460 dasd_profile_end(struct dasd_device *device, struct dasd_ccw_req * cqr,
 461                  struct request *req)
 462 {
 463         long strtime, irqtime, endtime, tottime;        /* in microseconds */
 464         long tottimeps, sectors;
 465
 466         if (dasd_profile_level != DASD_PROFILE_ON)
 467                 return;
 468
 469         sectors = req->nr_sectors;
 470         if (!cqr->buildclk || !cqr->startclk ||
 471             !cqr->stopclk || !cqr->endclk ||
 472             !sectors)
 473                 return;
 474
 475         strtime = ((cqr->startclk - cqr->buildclk) >> 12);
 476         irqtime = ((cqr->stopclk - cqr->startclk) >> 12);
 477         endtime = ((cqr->endclk - cqr->stopclk) >> 12);
 478         tottime = ((cqr->endclk - cqr->buildclk) >> 12);
 479         tottimeps = tottime / sectors;
 480
 481         if (!dasd_global_profile.dasd_io_reqs)
 482                 memset(&dasd_global_profile, 0,
 483                        sizeof (struct dasd_profile_info_t));
 484         dasd_global_profile.dasd_io_reqs++;
 485         dasd_global_profile.dasd_io_sects += sectors;
 486
 487         if (!device->profile.dasd_io_reqs)
 488                 memset(&device->profile, 0,
 489                        sizeof (struct dasd_profile_info_t));
 490         device->profile.dasd_io_reqs++;
 491         device->profile.dasd_io_sects += sectors;
 492
 493         dasd_profile_counter(sectors, dasd_io_secs, device);
 494         dasd_profile_counter(tottime, dasd_io_times, device);
 495         dasd_profile_counter(tottimeps, dasd_io_timps, device);
 496         dasd_profile_counter(strtime, dasd_io_time1, device);
 497         dasd_profile_counter(irqtime, dasd_io_time2, device);
 498         dasd_profile_counter(irqtime / sectors, dasd_io_time2ps, device);
 499         dasd_profile_counter(endtime, dasd_io_time3, device);
 500 }
 501 #else
 502 #define dasd_profile_start(device, cqr, req) do {} while (0)
 503 #define dasd_profile_end(device, cqr, req) do {} while (0)
 504 #endif                          /* CONFIG_DASD_PROFILE */
 505
 506 /*
 507  * Allocate memory for a channel program with 'cplength' channel
 508  * command words and 'datasize' additional space. There are two
 509  * variantes: 1) dasd_kmalloc_request uses kmalloc to get the needed
 510  * memory and 2) dasd_smalloc_request uses the static ccw memory
 511  * that gets allocated for each device.
 512  */
 513 struct dasd_ccw_req *
 514 dasd_kmalloc_request(char *magic, int cplength, int datasize,
 515                    struct dasd_device * device)
 516 {
 517         struct dasd_ccw_req *cqr;
 518
 519         /* Sanity checks */
 520         if ( magic == NULL || datasize > PAGE_SIZE ||
 521              (cplength*sizeof(struct ccw1)) > PAGE_SIZE)
 522                 BUG();
 523         debug_text_event ( dasd_debug_area, 1, "ALLC");
 524         debug_text_event ( dasd_debug_area, 1, magic);
 525         debug_int_event ( dasd_debug_area, 1, cplength);
 526         debug_int_event ( dasd_debug_area, 1, datasize);
 527
 528         cqr = kmalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
 529         if (cqr == NULL)
 530                 return ERR_PTR(-ENOMEM);
 531         memset(cqr, 0, sizeof(struct dasd_ccw_req));
 532         cqr->cpaddr = NULL;
 533         if (cplength > 0) {
 534                 cqr->cpaddr = kmalloc(cplength*sizeof(struct ccw1),
 535                                       GFP_ATOMIC | GFP_DMA);
 536                 if (cqr->cpaddr == NULL) {
 537                         kfree(cqr);
 538                         return ERR_PTR(-ENOMEM);
 539                 }
 540                 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
 541         }
 542         cqr->data = NULL;
 543         if (datasize > 0) {
 544                 cqr->data = kmalloc(datasize, GFP_ATOMIC | GFP_DMA);
 545                 if (cqr->data == NULL) {
 546                         if (cqr->cpaddr != NULL)
 547                                 kfree(cqr->cpaddr);
 548                         kfree(cqr);
 549                         return ERR_PTR(-ENOMEM);
 550                 }
 551                 memset(cqr->data, 0, datasize);
 552         }
 553         strncpy((char *) &cqr->magic, magic, 4);
 554         ASCEBC((char *) &cqr->magic, 4);
 555         set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
 556         dasd_get_device(device);
 557         return cqr;
 558 }
 559
 560 struct dasd_ccw_req *
 561 dasd_smalloc_request(char *magic, int cplength, int datasize,
 562                    struct dasd_device * device)
 563 {
 564         unsigned long flags;
 565         struct dasd_ccw_req *cqr;
 566         char *data;
 567         int size;
 568
 569         /* Sanity checks */
 570         if ( magic == NULL || datasize > PAGE_SIZE ||
 571              (cplength*sizeof(struct ccw1)) > PAGE_SIZE)
 572                 BUG();
 573         debug_text_event ( dasd_debug_area, 1, "ALLC");
 574         debug_text_event ( dasd_debug_area, 1, magic);
 575         debug_int_event ( dasd_debug_area, 1, cplength);
 576         debug_int_event ( dasd_debug_area, 1, datasize);
 577
 578         size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
 579         if (cplength > 0)
 580                 size += cplength * sizeof(struct ccw1);
 581         if (datasize > 0)
 582                 size += datasize;
 583         spin_lock_irqsave(&device->mem_lock, flags);
 584         cqr = (struct dasd_ccw_req *)
 585                 dasd_alloc_chunk(&device->ccw_chunks, size);
 586         spin_unlock_irqrestore(&device->mem_lock, flags);
 587         if (cqr == NULL)
 588                 return ERR_PTR(-ENOMEM);
 589         memset(cqr, 0, sizeof(struct dasd_ccw_req));
 590         data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
 591         cqr->cpaddr = NULL;
 592         if (cplength > 0) {
 593                 cqr->cpaddr = (struct ccw1 *) data;
 594                 data += cplength*sizeof(struct ccw1);
 595                 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
 596         }
 597         cqr->data = NULL;
 598         if (datasize > 0) {
 599                 cqr->data = data;
 600                 memset(cqr->data, 0, datasize);
 601         }
 602         strncpy((char *) &cqr->magic, magic, 4);
 603         ASCEBC((char *) &cqr->magic, 4);
 604         set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
 605         dasd_get_device(device);
 606         return cqr;
 607 }
 608
 609 /*
 610  * Free memory of a channel program. This function needs to free all the
 611  * idal lists that might have been created by dasd_set_cda and the
 612  * struct dasd_ccw_req itself.
 613  */
 614 void
 615 dasd_kfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
 616 {
 617 #ifdef CONFIG_ARCH_S390X
 618         struct ccw1 *ccw;
 619
 620         /* Clear any idals used for the request. */
 621         ccw = cqr->cpaddr;
 622         do {
 623                 clear_normalized_cda(ccw);
 624         } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
 625 #endif
 626         if (cqr->dstat != NULL)
 627                 kfree(cqr->dstat);
 628         debug_text_event ( dasd_debug_area, 1, "FREE");
 629         debug_int_event ( dasd_debug_area, 1, (long) cqr);
 630         if (cqr->cpaddr != NULL)
 631                 kfree(cqr->cpaddr);
 632         if (cqr->data != NULL)
 633                 kfree(cqr->data);
 634         kfree(cqr);
 635         dasd_put_device(device);
 636 }
 637
 638 void
 639 dasd_sfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
 640 {
 641         unsigned long flags;
 642
 643         if (cqr->dstat != NULL)
 644                 kfree(cqr->dstat);
 645         debug_text_event(dasd_debug_area, 1, "FREE");
 646         debug_int_event(dasd_debug_area, 1, (long) cqr);
 647         spin_lock_irqsave(&device->mem_lock, flags);
 648         dasd_free_chunk(&device->ccw_chunks, cqr);
 649         spin_unlock_irqrestore(&device->mem_lock, flags);
 650         dasd_put_device(device);
 651 }
 652
 653 /*
 654  * Check discipline magic in cqr.
 655  */
 656 static inline int
 657 dasd_check_cqr(struct dasd_ccw_req *cqr)
 658 {
 659         struct dasd_device *device;
 660
 661         if (cqr == NULL)
 662                 return -EINVAL;
 663         device = cqr->device;
 664         if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
 665                 DEV_MESSAGE(KERN_WARNING, device,
 666                             " dasd_ccw_req 0x%08x magic doesn't match"
 667                             " discipline 0x%08x",
 668                             cqr->magic,
 669                             *(unsigned int *) device->discipline->name);
 670                 return -EINVAL;
 671         }
 672         return 0;
 673 }
 674
 675 /*
 676  * Terminate the current i/o and set the request to failed.
 677  * ccw_device_clear can fail if the i/o subsystem
 678  * is in a bad mood.
 679  */
 680 int
 681 dasd_term_IO(struct dasd_ccw_req * cqr)
 682 {
 683         struct dasd_device *device;
 684         int retries, rc;
 685
 686         /* Check the cqr */
 687         rc = dasd_check_cqr(cqr);
 688         if (rc)
 689                 return rc;
 690         retries = 0;
 691         device = (struct dasd_device *) cqr->device;
 692         while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
 693                 rc = ccw_device_clear(device->cdev, (long) cqr);
 694                 switch (rc) {
 695                 case 0: /* termination successful */
 696                         if (cqr->retries > 0) {
 697                                 cqr->retries--;
 698                                 cqr->status = DASD_CQR_QUEUED;
 699                         } else
 700                                 cqr->status = DASD_CQR_FAILED;
 701                         cqr->stopclk = get_clock();
 702                         break;
 703                 case -ENODEV:
 704                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
 705                                       "device gone, retry");
 706                         break;
 707                 case -EIO:
 708                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
 709                                       "I/O error, retry");
 710                         break;
 711                 case -EINVAL:
 712                 case -EBUSY:
 713                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
 714                                       "device busy, retry later");
 715                         break;
 716                 default:
 717                         DEV_MESSAGE(KERN_ERR, device,
 718                                     "line %d unknown RC=%d, please "
 719                                     "report to linux390@de.ibm.com",
 720                                     __LINE__, rc);
 721                         BUG();
 722                         break;
 723                 }
 724                 retries++;
 725         }
 726         dasd_schedule_bh(device);
 727         return rc;
 728 }
 729
 730 /*
 731  * Start the i/o. This start_IO can fail if the channel is really busy.
 732  * In that case set up a timer to start the request later.
 733  */
 734 int
 735 dasd_start_IO(struct dasd_ccw_req * cqr)
 736 {
 737         struct dasd_device *device;
 738         int rc;
 739
 740         /* Check the cqr */
 741         rc = dasd_check_cqr(cqr);
 742         if (rc)
 743                 return rc;
 744         device = (struct dasd_device *) cqr->device;
 745         cqr->startclk = get_clock();
 746         cqr->starttime = jiffies;
 747         rc = ccw_device_start(device->cdev, cqr->cpaddr, (long) cqr,
 748                               cqr->lpm, 0);
 749         switch (rc) {
 750         case 0:
 751                 cqr->status = DASD_CQR_IN_IO;
 752                 break;
 753         case -EBUSY:
 754                 DBF_DEV_EVENT(DBF_ERR, device, "%s",
 755                               "start_IO: device busy, retry later");
 756                 break;
 757         case -ETIMEDOUT:
 758                 DBF_DEV_EVENT(DBF_ERR, device, "%s",
 759                               "start_IO: request timeout, retry later");
 760                 break;
 761         case -ENODEV:
 762         case -EIO:
 763                 DBF_DEV_EVENT(DBF_ERR, device, "%s",
 764                               "start_IO: device gone, retry");
 765                 break;
 766         default:
 767                 DEV_MESSAGE(KERN_ERR, device,
 768                             "line %d unknown RC=%d, please report"
 769                             " to linux390@de.ibm.com", __LINE__, rc);
 770                 BUG();
 771                 break;
 772         }
 773         return rc;
 774 }
 775
 776 /*
 777  * Timeout function for dasd devices. This is used for different purposes
 778  *  1) missing interrupt handler for normal operation
 779  *  2) delayed start of request where start_IO failed with -EBUSY
 780  *  3) timeout for missing state change interrupts
 781  * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
 782  * DASD_CQR_QUEUED for 2) and 3).
 783  */
 784 static void
 785 dasd_timeout_device(unsigned long ptr)
 786 {
 787         unsigned long flags;
 788         struct dasd_device *device;
 789
 790         device = (struct dasd_device *) ptr;
 791         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 792         /* re-activate request queue */
 793         device->stopped &= ~DASD_STOPPED_PENDING;
 794         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 795         dasd_schedule_bh(device);
 796 }
 797
 798 /*
 799  * Setup timeout for a device in jiffies.
 800  */
 801 void
 802 dasd_set_timer(struct dasd_device *device, int expires)
 803 {
 804         if (expires == 0) {
 805                 if (timer_pending(&device->timer))
 806                         del_timer(&device->timer);
 807                 return;
 808         }
 809         if (timer_pending(&device->timer)) {
 810                 if (mod_timer(&device->timer, jiffies + expires))
 811                         return;
 812         }
 813         device->timer.function = dasd_timeout_device;
 814         device->timer.data = (unsigned long) device;
 815         device->timer.expires = jiffies + expires;
 816         add_timer(&device->timer);
 817 }
 818
 819 /*
 820  * Clear timeout for a device.
 821  */
 822 void
 823 dasd_clear_timer(struct dasd_device *device)
 824 {
 825         if (timer_pending(&device->timer))
 826                 del_timer(&device->timer);
 827 }
 828
 829 /*
 830  *   Handles the state change pending interrupt.
 831  */
 832 static void
 833 do_state_change_pending(void *data)
 834 {
 835         struct {
 836                 struct work_struct work;
 837                 struct dasd_device *device;
 838         } *p;
 839         struct dasd_device *device;
 840         struct dasd_ccw_req *cqr;
 841         struct list_head *l, *n;
 842         unsigned long flags;
 843
 844         p = data;
 845         device = p->device;
 846         DBF_EVENT(DBF_NOTICE, "State change Interrupt for bus_id %s",
 847                   device->cdev->dev.bus_id);
 848         device->stopped &= ~DASD_STOPPED_PENDING;
 849
 850         /* restart all 'running' IO on queue */
 851         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 852         list_for_each_safe(l, n, &device->ccw_queue) {
 853                 cqr = list_entry(l, struct dasd_ccw_req, list);
 854                 if (cqr->status == DASD_CQR_IN_IO)
 855                         cqr->status = DASD_CQR_QUEUED;
 856         }
 857         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 858         dasd_set_timer (device, 0);
 859         dasd_schedule_bh(device);
 860         dasd_put_device(device);
 861         kfree(p);
 862 }
 863
 864 static void
 865 dasd_handle_killed_request(struct ccw_device *cdev, unsigned long intparm)
 866 {
 867         struct dasd_ccw_req *cqr;
 868         struct dasd_device *device;
 869
 870         cqr = (struct dasd_ccw_req *) intparm;
 871         if (cqr->status != DASD_CQR_IN_IO) {
 872                 MESSAGE(KERN_DEBUG,
 873                         "invalid status in handle_killed_request: "
 874                         "bus_id %s, status %02x",
 875                         cdev->dev.bus_id, cqr->status);
 876                 return;
 877         }
 878
 879         device = (struct dasd_device *) cqr->device;
 880         if (device == NULL ||
 881             device != dasd_device_from_cdev(cdev) ||
 882             strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 883                 MESSAGE(KERN_DEBUG, "invalid device in request: bus_id %s",
 884                         cdev->dev.bus_id);
 885                 return;
 886         }
 887
 888         /* Schedule request to be retried. */
 889         cqr->status = DASD_CQR_QUEUED;
 890
 891         dasd_clear_timer(device);
 892         dasd_schedule_bh(device);
 893         dasd_put_device(device);
 894 }
 895
 896 static void
 897 dasd_handle_state_change_pending(struct dasd_device *device)
 898 {
 899         struct {
 900                 struct work_struct work;
 901                 struct dasd_device *device;
 902         } *p;
 903
 904         p = kmalloc(sizeof(*p), GFP_ATOMIC);
 905         if (p == NULL)
 906                 /* No memory, let the timeout do the reactivation. */
 907                 return;
 908         INIT_WORK(&p->work, (void *) do_state_change_pending, p);
 909         p->device = device;
 910         dasd_get_device(device);
 911         schedule_work(&p->work);
 912 }
 913
 914 /*
 915  * Interrupt handler for "normal" ssch-io based dasd devices.
 916  */
 917 void
 918 dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
 919                  struct irb *irb)
 920 {
 921         struct dasd_ccw_req *cqr, *next;
 922         struct dasd_device *device;
 923         unsigned long long now;
 924         int expires;
 925         dasd_era_t era;
 926         char mask;
 927
 928         if (IS_ERR(irb)) {
 929                 switch (PTR_ERR(irb)) {
 930                 case -EIO:
 931                         dasd_handle_killed_request(cdev, intparm);
 932                         break;
 933                 case -ETIMEDOUT:
 934                         printk(KERN_WARNING"%s(%s): request timed out\n",
 935                                __FUNCTION__, cdev->dev.bus_id);
 936                         //FIXME - dasd uses own timeout interface...
 937                         break;
 938                 default:
 939                         printk(KERN_WARNING"%s(%s): unknown error %ld\n",
 940                                __FUNCTION__, cdev->dev.bus_id, PTR_ERR(irb));
 941                 }
 942                 return;
 943         }
 944
 945         now = get_clock();
 946
 947         DBF_EVENT(DBF_DEBUG, "Interrupt: stat %02x, bus_id %s",
 948                   irb->scsw.dstat, cdev->dev.bus_id);
 949
 950         /* first of all check for state change pending interrupt */
 951         mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
 952         if ((irb->scsw.dstat & mask) == mask) {
 953                 device = dasd_device_from_cdev(cdev);
 954                 if (!IS_ERR(device)) {
 955                         dasd_handle_state_change_pending(device);
 956                         dasd_put_device(device);
 957                 }
 958                 return;
 959         }
 960
 961         cqr = (struct dasd_ccw_req *) intparm;
 962         /*
 963          * check status - the request might have been killed
 964          * because of dyn detach
 965          */
 966         if (cqr->status != DASD_CQR_IN_IO) {
 967                 MESSAGE(KERN_DEBUG,
 968                         "invalid status: bus_id %s, status %02x",
 969                         cdev->dev.bus_id, cqr->status);
 970                 return;
 971         }
 972
 973         device = (struct dasd_device *) cqr->device;
 974         if (device == NULL ||
 975             strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 976                 MESSAGE(KERN_DEBUG, "invalid device in request: bus_id %s",
 977                         cdev->dev.bus_id);
 978                 return;
 979         }
 980
 981         DBF_DEV_EVENT(DBF_DEBUG, device, "Int: CS/DS 0x%04x",
 982                       ((irb->scsw.cstat << 8) | irb->scsw.dstat));
 983
 984         /* Find out the appropriate era_action. */
 985         if (irb->scsw.fctl & SCSW_FCTL_HALT_FUNC)
 986                 era = dasd_era_fatal;
 987         else if (irb->scsw.dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
 988                  irb->scsw.cstat == 0 &&
 989                  !irb->esw.esw0.erw.cons)
 990                 era = dasd_era_none;
 991         else if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags))
 992                 era = dasd_era_fatal; /* don't recover this request */
 993         else if (irb->esw.esw0.erw.cons)
 994                 era = device->discipline->examine_error(cqr, irb);
 995         else
 996                 era = dasd_era_recover;
 997
 998         DBF_DEV_EVENT(DBF_DEBUG, device, "era_code %d", era);
 999         expires = 0;
1000         if (era == dasd_era_none) {
1001                 cqr->status = DASD_CQR_DONE;
1002                 cqr->stopclk = now;
1003                 /* Start first request on queue if possible -> fast_io. */
1004                 if (cqr->list.next != &device->ccw_queue) {
1005                         next = list_entry(cqr->list.next,
1006                                           struct dasd_ccw_req, list);
1007                         if ((next->status == DASD_CQR_QUEUED) &&
1008                             (!device->stopped)) {
1009                                 if (device->discipline->start_IO(next) == 0)
1010                                         expires = next->expires;
1011                                 else
1012                                         DEV_MESSAGE(KERN_DEBUG, device, "%s",
1013                                                     "Interrupt fastpath "
1014                                                     "failed!");
1015                         }
1016                 }
1017         } else {                /* error */
1018                 if (cqr->dstat == NULL)
1019                         cqr->dstat = kmalloc(sizeof(struct irb), GFP_ATOMIC);
1020                 if (cqr->dstat)
1021                         memcpy(cqr->dstat, irb, sizeof (struct irb));
1022                 else
1023                         DEV_MESSAGE(KERN_ERR, device, "%s",
1024                                     "no memory for dstat...ignoring");
1025 #ifdef ERP_DEBUG
1026                 /* dump sense data */
1027                 dasd_log_sense(cqr, irb);
1028 #endif
1029                 switch (era) {
1030                 case dasd_era_fatal:
1031                         cqr->status = DASD_CQR_FAILED;
1032                         cqr->stopclk = now;
1033                         break;
1034                 case dasd_era_recover:
1035                         cqr->status = DASD_CQR_ERROR;
1036                         break;
1037                 default:
1038                         BUG();
1039                 }
1040         }
1041         if (expires != 0)
1042                 dasd_set_timer(device, expires);
1043         else
1044                 dasd_clear_timer(device);
1045         dasd_schedule_bh(device);
1046 }
1047
1048 /*
1049  * posts the buffer_cache about a finalized request
1050  */
1051 static inline void
1052 dasd_end_request(struct request *req, int uptodate)
1053 {
1054         if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
1055                 BUG();
1056         add_disk_randomness(req->rq_disk);
1057         end_that_request_last(req);
1058 }
1059
1060 /*
1061  * Process finished error recovery ccw.
1062  */
1063 static inline void
1064 __dasd_process_erp(struct dasd_device *device, struct dasd_ccw_req *cqr)
1065 {
1066         dasd_erp_fn_t erp_fn;
1067
1068         if (cqr->status == DASD_CQR_DONE)
1069                 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
1070         else
1071                 DEV_MESSAGE(KERN_ERR, device, "%s", "ERP unsuccessful");
1072         erp_fn = device->discipline->erp_postaction(cqr);
1073         erp_fn(cqr);
1074 }
1075
1076 /*
1077  * Process ccw request queue.
1078  */
1079 static inline void
1080 __dasd_process_ccw_queue(struct dasd_device * device,
1081                          struct list_head *final_queue)
1082 {
1083         struct list_head *l, *n;
1084         struct dasd_ccw_req *cqr;
1085         dasd_erp_fn_t erp_fn;
1086
1087 restart:
1088         /* Process request with final status. */
1089         list_for_each_safe(l, n, &device->ccw_queue) {
1090                 cqr = list_entry(l, struct dasd_ccw_req, list);
1091                 /* Stop list processing at the first non-final request. */
1092                 if (cqr->status != DASD_CQR_DONE &&
1093                     cqr->status != DASD_CQR_FAILED &&
1094                     cqr->status != DASD_CQR_ERROR)
1095                         break;
1096                 /*  Process requests with DASD_CQR_ERROR */
1097                 if (cqr->status == DASD_CQR_ERROR) {
1098                         cqr->retries--;
1099                         if (cqr->dstat->scsw.fctl & SCSW_FCTL_HALT_FUNC) {
1100                                 cqr->status = DASD_CQR_FAILED;
1101                                 cqr->stopclk = get_clock();
1102                         } else {
1103                                 if (cqr->dstat->esw.esw0.erw.cons) {
1104                                         erp_fn = device->discipline->erp_action(cqr);
1105                                         erp_fn(cqr);
1106                                 } else
1107                                         dasd_default_erp_action(cqr);
1108                         }
1109                         goto restart;
1110                 }
1111                 /* Process finished ERP request. */
1112                 if (cqr->refers) {
1113                         __dasd_process_erp(device, cqr);
1114                         goto restart;
1115                 }
1116
1117                 /* Rechain finished requests to final queue */
1118                 cqr->endclk = get_clock();
1119                 list_move_tail(&cqr->list, final_queue);
1120         }
1121 }
1122
1123 static void
1124 dasd_end_request_cb(struct dasd_ccw_req * cqr, void *data)
1125 {
1126         struct request *req;
1127
1128         req = (struct request *) data;
1129         dasd_profile_end(cqr->device, cqr, req);
1130         spin_lock_irq(&cqr->device->request_queue_lock);
1131         dasd_end_request(req, (cqr->status == DASD_CQR_DONE));
1132         spin_unlock_irq(&cqr->device->request_queue_lock);
1133         dasd_sfree_request(cqr, cqr->device);
1134 }
1135
1136
1137 /*
1138  * Fetch requests from the block device queue.
1139  */
1140 static inline void
1141 __dasd_process_blk_queue(struct dasd_device * device)
1142 {
1143         request_queue_t *queue;
1144         struct request *req;
1145         struct dasd_ccw_req *cqr;
1146         int nr_queued;
1147
1148         queue = device->request_queue;
1149         /* No queue ? Then there is nothing to do. */
1150         if (queue == NULL)
1151                 return;
1152
1153         /*
1154          * We requeue request from the block device queue to the ccw
1155          * queue only in two states. In state DASD_STATE_READY the
1156          * partition detection is done and we need to requeue requests
1157          * for that. State DASD_STATE_ONLINE is normal block device
1158          * operation.
1159          */
1160         if (device->state != DASD_STATE_READY &&
1161             device->state != DASD_STATE_ONLINE)
1162                 return;
1163         nr_queued = 0;
1164         /* Now we try to fetch requests from the request queue */
1165         list_for_each_entry(cqr, &device->ccw_queue, list)
1166                 if (cqr->status == DASD_CQR_QUEUED)
1167                         nr_queued++;
1168         while (!blk_queue_plugged(queue) &&
1169                elv_next_request(queue) &&
1170                 nr_queued < DASD_CHANQ_MAX_SIZE) {
1171                 req = elv_next_request(queue);
1172                 if (test_bit(DASD_FLAG_RO, &device->flags) &&
1173                     rq_data_dir(req) == WRITE) {
1174                         DBF_EVENT(DBF_ERR,
1175                                   "(%s) Rejecting write request %p",
1176                                   device->cdev->dev.bus_id,
1177                                   req);
1178                         blkdev_dequeue_request(req);
1179                         dasd_end_request(req, 0);
1180                         continue;
1181                 }
1182                 if (device->stopped & DASD_STOPPED_DC_EIO) {
1183                         blkdev_dequeue_request(req);
1184                         dasd_end_request(req, 0);
1185                         continue;
1186                 }
1187                 cqr = device->discipline->build_cp(device, req);
1188                 if (IS_ERR(cqr)) {
1189                         if (PTR_ERR(cqr) == -ENOMEM)
1190                                 break;  /* terminate request queue loop */
1191                         DBF_EVENT(DBF_ERR,
1192                                   "(%s) CCW creation failed on request %p",
1193                                   device->cdev->dev.bus_id,
1194                                   req);
1195                         blkdev_dequeue_request(req);
1196                         dasd_end_request(req, 0);
1197                         continue;
1198                 }
1199                 cqr->callback = dasd_end_request_cb;
1200                 cqr->callback_data = (void *) req;
1201                 cqr->status = DASD_CQR_QUEUED;
1202                 blkdev_dequeue_request(req);
1203                 list_add_tail(&cqr->list, &device->ccw_queue);
1204                 dasd_profile_start(device, cqr, req);
1205                 nr_queued++;
1206         }
1207 }
1208
1209 /*
1210  * Take a look at the first request on the ccw queue and check
1211  * if it reached its expire time. If so, terminate the IO.
1212  */
1213 static inline void
1214 __dasd_check_expire(struct dasd_device * device)
1215 {
1216         struct dasd_ccw_req *cqr;
1217
1218         if (list_empty(&device->ccw_queue))
1219                 return;
1220         cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
1221         if (cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) {
1222                 if (time_after_eq(jiffies, cqr->expires + cqr->starttime)) {
1223                         if (device->discipline->term_IO(cqr) != 0)
1224                                 /* Hmpf, try again in 1/100 sec */
1225                                 dasd_set_timer(device, 1);
1226                 }
1227         }
1228 }
1229
1230 /*
1231  * Take a look at the first request on the ccw queue and check
1232  * if it needs to be started.
1233  */
1234 static inline void
1235 __dasd_start_head(struct dasd_device * device)
1236 {
1237         struct dasd_ccw_req *cqr;
1238         int rc;
1239
1240         if (list_empty(&device->ccw_queue))
1241                 return;
1242         cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
1243         if ((cqr->status == DASD_CQR_QUEUED) &&
1244             (!device->stopped)) {
1245                 /* try to start the first I/O that can be started */
1246                 rc = device->discipline->start_IO(cqr);
1247                 if (rc == 0)
1248                         dasd_set_timer(device, cqr->expires);
1249                 else if (rc == -EBUSY)
1250                                 /* Hmpf, try again in 1/100 sec */
1251                         dasd_set_timer(device, 1);
1252         }
1253 }
1254
1255 /*
1256  * Remove requests from the ccw queue.
1257  */
1258 static void
1259 dasd_flush_ccw_queue(struct dasd_device * device, int all)
1260 {
1261         struct list_head flush_queue;
1262         struct list_head *l, *n;
1263         struct dasd_ccw_req *cqr;
1264
1265         INIT_LIST_HEAD(&flush_queue);
1266         spin_lock_irq(get_ccwdev_lock(device->cdev));
1267         list_for_each_safe(l, n, &device->ccw_queue) {
1268                 cqr = list_entry(l, struct dasd_ccw_req, list);
1269                 /* Flush all request or only block device requests? */
1270                 if (all == 0 && cqr->callback == dasd_end_request_cb)
1271                         continue;
1272                 if (cqr->status == DASD_CQR_IN_IO)
1273                         device->discipline->term_IO(cqr);
1274                 if (cqr->status != DASD_CQR_DONE ||
1275                     cqr->status != DASD_CQR_FAILED) {
1276                         cqr->status = DASD_CQR_FAILED;
1277                         cqr->stopclk = get_clock();
1278                 }
1279                 /* Process finished ERP request. */
1280                 if (cqr->refers) {
1281                         __dasd_process_erp(device, cqr);
1282                         continue;
1283                 }
1284                 /* Rechain request on device request queue */
1285                 cqr->endclk = get_clock();
1286                 list_move_tail(&cqr->list, &flush_queue);
1287         }
1288         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1289         /* Now call the callback function of flushed requests */
1290         list_for_each_safe(l, n, &flush_queue) {
1291                 cqr = list_entry(l, struct dasd_ccw_req, list);
1292                 if (cqr->callback != NULL)
1293                         (cqr->callback)(cqr, cqr->callback_data);
1294         }
1295 }
1296
1297 /*
1298  * Acquire the device lock and process queues for the device.
1299  */
1300 static void
1301 dasd_tasklet(struct dasd_device * device)
1302 {
1303         struct list_head final_queue;
1304         struct list_head *l, *n;
1305         struct dasd_ccw_req *cqr;
1306
1307         atomic_set (&device->tasklet_scheduled, 0);
1308         INIT_LIST_HEAD(&final_queue);
1309         spin_lock_irq(get_ccwdev_lock(device->cdev));
1310         /* Check expire time of first request on the ccw queue. */
1311         __dasd_check_expire(device);
1312         /* Finish off requests on ccw queue */
1313         __dasd_process_ccw_queue(device, &final_queue);
1314         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1315         /* Now call the callback function of requests with final status */
1316         list_for_each_safe(l, n, &final_queue) {
1317                 cqr = list_entry(l, struct dasd_ccw_req, list);
1318                 list_del(&cqr->list);
1319                 if (cqr->callback != NULL)
1320                         (cqr->callback)(cqr, cqr->callback_data);
1321         }
1322         spin_lock_irq(&device->request_queue_lock);
1323         spin_lock(get_ccwdev_lock(device->cdev));
1324         /* Get new request from the block device request queue */
1325         __dasd_process_blk_queue(device);
1326         /* Now check if the head of the ccw queue needs to be started. */
1327         __dasd_start_head(device);
1328         spin_unlock(get_ccwdev_lock(device->cdev));
1329         spin_unlock_irq(&device->request_queue_lock);
1330         dasd_put_device(device);
1331 }
1332
1333 /*
1334  * Schedules a call to dasd_tasklet over the device tasklet.
1335  */
1336 void
1337 dasd_schedule_bh(struct dasd_device * device)
1338 {
1339         /* Protect against rescheduling. */
1340         if (atomic_compare_and_swap (0, 1, &device->tasklet_scheduled))
1341                 return;
1342         dasd_get_device(device);
1343         tasklet_hi_schedule(&device->tasklet);
1344 }
1345
1346 /*
1347  * Queue a request to the head of the ccw_queue. Start the I/O if
1348  * possible.
1349  */
1350 void
1351 dasd_add_request_head(struct dasd_ccw_req *req)
1352 {
1353         struct dasd_device *device;
1354         unsigned long flags;
1355
1356         device = req->device;
1357         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1358         req->status = DASD_CQR_QUEUED;
1359         req->device = device;
1360         list_add(&req->list, &device->ccw_queue);
1361         /* let the bh start the request to keep them in order */
1362         dasd_schedule_bh(device);
1363         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1364 }
1365
1366 /*
1367  * Queue a request to the tail of the ccw_queue. Start the I/O if
1368  * possible.
1369  */
1370 void
1371 dasd_add_request_tail(struct dasd_ccw_req *req)
1372 {
1373         struct dasd_device *device;
1374         unsigned long flags;
1375
1376         device = req->device;
1377         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1378         req->status = DASD_CQR_QUEUED;
1379         req->device = device;
1380         list_add_tail(&req->list, &device->ccw_queue);
1381         /* let the bh start the request to keep them in order */
1382         dasd_schedule_bh(device);
1383         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1384 }
1385
1386 /*
1387  * Wakeup callback.
1388  */
1389 static void
1390 dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
1391 {
1392         wake_up((wait_queue_head_t *) data);
1393 }
1394
1395 static inline int
1396 _wait_for_wakeup(struct dasd_ccw_req *cqr)
1397 {
1398         struct dasd_device *device;
1399         int rc;
1400
1401         device = cqr->device;
1402         spin_lock_irq(get_ccwdev_lock(device->cdev));
1403         rc = cqr->status == DASD_CQR_DONE || cqr->status == DASD_CQR_FAILED;
1404         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1405         return rc;
1406 }
1407
1408 /*
1409  * Attempts to start a special ccw queue and waits for its completion.
1410  */
1411 int
1412 dasd_sleep_on(struct dasd_ccw_req * cqr)
1413 {
1414         wait_queue_head_t wait_q;
1415         struct dasd_device *device;
1416         int rc;
1417
1418         device = cqr->device;
1419         spin_lock_irq(get_ccwdev_lock(device->cdev));
1420
1421         init_waitqueue_head (&wait_q);
1422         cqr->callback = dasd_wakeup_cb;
1423         cqr->callback_data = (void *) &wait_q;
1424         cqr->status = DASD_CQR_QUEUED;
1425         list_add_tail(&cqr->list, &device->ccw_queue);
1426
1427         /* let the bh start the request to keep them in order */
1428         dasd_schedule_bh(device);
1429
1430         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1431
1432         wait_event(wait_q, _wait_for_wakeup(cqr));
1433
1434         /* Request status is either done or failed. */
1435         rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
1436         return rc;
1437 }
1438
1439 /*
1440  * Attempts to start a special ccw queue and wait interruptible
1441  * for its completion.
1442  */
1443 int
1444 dasd_sleep_on_interruptible(struct dasd_ccw_req * cqr)
1445 {
1446         wait_queue_head_t wait_q;
1447         struct dasd_device *device;
1448         int rc, finished;
1449
1450         device = cqr->device;
1451         spin_lock_irq(get_ccwdev_lock(device->cdev));
1452
1453         init_waitqueue_head (&wait_q);
1454         cqr->callback = dasd_wakeup_cb;
1455         cqr->callback_data = (void *) &wait_q;
1456         cqr->status = DASD_CQR_QUEUED;
1457         list_add_tail(&cqr->list, &device->ccw_queue);
1458
1459         /* let the bh start the request to keep them in order */
1460         dasd_schedule_bh(device);
1461         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1462
1463         finished = 0;
1464         while (!finished) {
1465                 rc = wait_event_interruptible(wait_q, _wait_for_wakeup(cqr));
1466                 if (rc != -ERESTARTSYS) {
1467                         /* Request status is either done or failed. */
1468                         rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
1469                         break;
1470                 }
1471                 spin_lock_irq(get_ccwdev_lock(device->cdev));
1472                 if (cqr->status == DASD_CQR_IN_IO &&
1473                     device->discipline->term_IO(cqr) == 0) {
1474                         list_del(&cqr->list);
1475                         finished = 1;
1476                 }
1477                 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1478         }
1479         return rc;
1480 }
1481
1482 /*
1483  * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
1484  * for eckd devices) the currently running request has to be terminated
1485  * and be put back to status queued, before the special request is added
1486  * to the head of the queue. Then the special request is waited on normally.
1487  */
1488 static inline int
1489 _dasd_term_running_cqr(struct dasd_device *device)
1490 {
1491         struct dasd_ccw_req *cqr;
1492         int rc;
1493
1494         if (list_empty(&device->ccw_queue))
1495                 return 0;
1496         cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
1497         rc = device->discipline->term_IO(cqr);
1498         if (rc == 0) {
1499                 /* termination successful */
1500                 cqr->status = DASD_CQR_QUEUED;
1501                 cqr->startclk = cqr->stopclk = 0;
1502                 cqr->starttime = 0;
1503         }
1504         return rc;
1505 }
1506
1507 int
1508 dasd_sleep_on_immediatly(struct dasd_ccw_req * cqr)
1509 {
1510         wait_queue_head_t wait_q;
1511         struct dasd_device *device;
1512         int rc;
1513
1514         device = cqr->device;
1515         spin_lock_irq(get_ccwdev_lock(device->cdev));
1516         rc = _dasd_term_running_cqr(device);
1517         if (rc) {
1518                 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1519                 return rc;
1520         }
1521
1522         init_waitqueue_head (&wait_q);
1523         cqr->callback = dasd_wakeup_cb;
1524         cqr->callback_data = (void *) &wait_q;
1525         cqr->status = DASD_CQR_QUEUED;
1526         list_add(&cqr->list, &device->ccw_queue);
1527
1528         /* let the bh start the request to keep them in order */
1529         dasd_schedule_bh(device);
1530
1531         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1532
1533         wait_event(wait_q, _wait_for_wakeup(cqr));
1534
1535         /* Request status is either done or failed. */
1536         rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
1537         return rc;
1538 }
1539
1540 /*
1541  * Cancels a request that was started with dasd_sleep_on_req.
1542  * This is useful to timeout requests. The request will be
1543  * terminated if it is currently in i/o.
1544  * Returns 1 if the request has been terminated.
1545  */
1546 int
1547 dasd_cancel_req(struct dasd_ccw_req *cqr)
1548 {
1549         struct dasd_device *device = cqr->device;
1550         unsigned long flags;
1551         int rc;
1552
1553         rc = 0;
1554         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1555         switch (cqr->status) {
1556         case DASD_CQR_QUEUED:
1557                 /* request was not started - just set to failed */
1558                 cqr->status = DASD_CQR_FAILED;
1559                 break;
1560         case DASD_CQR_IN_IO:
1561                 /* request in IO - terminate IO and release again */
1562                 if (device->discipline->term_IO(cqr) != 0)
1563                         /* what to do if unable to terminate ??????
1564                            e.g. not _IN_IO */
1565                         cqr->status = DASD_CQR_FAILED;
1566                 cqr->stopclk = get_clock();
1567                 rc = 1;
1568                 break;
1569         case DASD_CQR_DONE:
1570         case DASD_CQR_FAILED:
1571                 /* already finished - do nothing */
1572                 break;
1573         default:
1574                 DEV_MESSAGE(KERN_ALERT, device,
1575                             "invalid status %02x in request",
1576                             cqr->status);
1577                 BUG();
1578
1579         }
1580         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1581         dasd_schedule_bh(device);
1582         return rc;
1583 }
1584
1585 /*
1586  * SECTION: Block device operations (request queue, partitions, open, release).
1587  */
1588
1589 /*
1590  * Dasd request queue function. Called from ll_rw_blk.c
1591  */
1592 static void
1593 do_dasd_request(request_queue_t * queue)
1594 {
1595         struct dasd_device *device;
1596
1597         device = (struct dasd_device *) queue->queuedata;
1598         spin_lock(get_ccwdev_lock(device->cdev));
1599         /* Get new request from the block device request queue */
1600         __dasd_process_blk_queue(device);
1601         /* Now check if the head of the ccw queue needs to be started. */
1602         __dasd_start_head(device);
1603         spin_unlock(get_ccwdev_lock(device->cdev));
1604 }
1605
1606 /*
1607  * Allocate and initialize request queue.
1608  */
1609 static int
1610 dasd_alloc_queue(struct dasd_device * device)
1611 {
1612         device->request_queue = blk_init_queue(do_dasd_request,
1613                                                &device->request_queue_lock);
1614         if (device->request_queue == NULL)
1615                 return -ENOMEM;
1616
1617         device->request_queue->queuedata = device;
1618 #if 0
1619         elevator_exit(device->request_queue);
1620         rc = elevator_init(device->request_queue, &elevator_noop);
1621         if (rc) {
1622                 blk_cleanup_queue(device->request_queue);
1623                 return rc;
1624         }
1625 #endif
1626         return 0;
1627 }
1628
1629 /*
1630  * Allocate and initialize request queue.
1631  */
1632 static void
1633 dasd_setup_queue(struct dasd_device * device)
1634 {
1635         int max;
1636
1637         blk_queue_hardsect_size(device->request_queue, device->bp_block);
1638         max = device->discipline->max_blocks << device->s2b_shift;
1639         blk_queue_max_sectors(device->request_queue, max);
1640         blk_queue_max_phys_segments(device->request_queue, -1L);
1641         blk_queue_max_hw_segments(device->request_queue, -1L);
1642         blk_queue_max_segment_size(device->request_queue, -1L);
1643         blk_queue_segment_boundary(device->request_queue, -1L);
1644 }
1645
1646 /*
1647  * Deactivate and free request queue.
1648  */
1649 static void
1650 dasd_free_queue(struct dasd_device * device)
1651 {
1652         if (device->request_queue) {
1653                 blk_cleanup_queue(device->request_queue);
1654                 device->request_queue = NULL;
1655         }
1656 }
1657
1658 /*
1659  * Flush request on the request queue.
1660  */
1661 static void
1662 dasd_flush_request_queue(struct dasd_device * device)
1663 {
1664         struct request *req;
1665
1666         if (!device->request_queue)
1667                 return;
1668
1669         spin_lock_irq(&device->request_queue_lock);
1670         while (!list_empty(&device->request_queue->queue_head)) {
1671                 req = elv_next_request(device->request_queue);
1672                 if (req == NULL)
1673                         break;
1674                 dasd_end_request(req, 0);
1675                 blkdev_dequeue_request(req);
1676         }
1677         spin_unlock_irq(&device->request_queue_lock);
1678 }
1679
1680 static int
1681 dasd_open(struct inode *inp, struct file *filp)
1682 {
1683         struct gendisk *disk = inp->i_bdev->bd_disk;
1684         struct dasd_device *device = disk->private_data;
1685         int rc;
1686
1687         atomic_inc(&device->open_count);
1688         if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
1689                 rc = -ENODEV;
1690                 goto unlock;
1691         }
1692
1693         if (!try_module_get(device->discipline->owner)) {
1694                 rc = -EINVAL;
1695                 goto unlock;
1696         }
1697
1698         if (dasd_probeonly) {
1699                 MESSAGE(KERN_INFO,
1700                         "No access to device %s due to probeonly mode",
1701                         disk->disk_name);
1702                 rc = -EPERM;
1703                 goto out;
1704         }
1705
1706         if (device->state < DASD_STATE_BASIC) {
1707                 DBF_DEV_EVENT(DBF_ERR, device, " %s",
1708                               " Cannot open unrecognized device");
1709                 rc = -ENODEV;
1710                 goto out;
1711         }
1712
1713         return 0;
1714
1715 out:
1716         module_put(device->discipline->owner);
1717 unlock:
1718         atomic_dec(&device->open_count);
1719         return rc;
1720 }
1721
1722 static int
1723 dasd_release(struct inode *inp, struct file *filp)
1724 {
1725         struct gendisk *disk = inp->i_bdev->bd_disk;
1726         struct dasd_device *device = disk->private_data;
1727
1728         atomic_dec(&device->open_count);
1729         module_put(device->discipline->owner);
1730         return 0;
1731 }
1732
1733 struct block_device_operations
1734 dasd_device_operations = {
1735         .owner          = THIS_MODULE,
1736         .open           = dasd_open,
1737         .release        = dasd_release,
1738         .ioctl          = dasd_ioctl,
1739 };
1740
1741
1742 static void
1743 dasd_exit(void)
1744 {
1745 #ifdef CONFIG_PROC_FS
1746         dasd_proc_exit();
1747 #endif
1748         dasd_ioctl_exit();
1749         dasd_gendisk_exit();
1750         dasd_devmap_exit();
1751         devfs_remove("dasd");
1752         if (dasd_debug_area != NULL) {
1753                 debug_unregister(dasd_debug_area);
1754                 dasd_debug_area = NULL;
1755         }
1756 }
1757
1758 /*
1759  * SECTION: common functions for ccw_driver use
1760  */
1761
1762 /* initial attempt at a probe function. this can be simplified once
1763  * the other detection code is gone */
1764 int
1765 dasd_generic_probe (struct ccw_device *cdev,
1766                     struct dasd_discipline *discipline)
1767 {
1768         int ret;
1769
1770         ret = dasd_add_sysfs_files(cdev);
1771         if (ret) {
1772                 printk(KERN_WARNING
1773                        "dasd_generic_probe: could not add sysfs entries "
1774                        "for %s\n", cdev->dev.bus_id);
1775         }
1776
1777         cdev->handler = &dasd_int_handler;
1778
1779         return ret;
1780 }
1781
1782 /* this will one day be called from a global not_oper handler.
1783  * It is also used by driver_unregister during module unload */
1784 void
1785 dasd_generic_remove (struct ccw_device *cdev)
1786 {
1787         struct dasd_device *device;
1788
1789         dasd_remove_sysfs_files(cdev);
1790         device = dasd_device_from_cdev(cdev);
1791         if (IS_ERR(device))
1792                 return;
1793         if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
1794                 /* Already doing offline processing */
1795                 dasd_put_device(device);
1796                 return;
1797         }
1798         /*
1799          * This device is removed unconditionally. Set offline
1800          * flag to prevent dasd_open from opening it while it is
1801          * no quite down yet.
1802          */
1803         dasd_set_target_state(device, DASD_STATE_NEW);
1804         /* dasd_delete_device destroys the device reference. */
1805         dasd_delete_device(device);
1806 }
1807
1808 /* activate a device. This is called from dasd_{eckd,fba}_probe() when either
1809  * the device is detected for the first time and is supposed to be used
1810  * or the user has started activation through sysfs */
1811 int
1812 dasd_generic_set_online (struct ccw_device *cdev,
1813                          struct dasd_discipline *discipline)
1814
1815 {
1816         struct dasd_device *device;
1817         int rc;
1818
1819         device = dasd_create_device(cdev);
1820         if (IS_ERR(device))
1821                 return PTR_ERR(device);
1822
1823         if (test_bit(DASD_FLAG_USE_DIAG, &device->flags)) {
1824                 if (!dasd_diag_discipline_pointer) {
1825                         printk (KERN_WARNING
1826                                 "dasd_generic couldn't online device %s "
1827                                 "- discipline DIAG not available\n",
1828                                 cdev->dev.bus_id);
1829                         dasd_delete_device(device);
1830                         return -ENODEV;
1831                 }
1832                 discipline = dasd_diag_discipline_pointer;
1833         }
1834         device->discipline = discipline;
1835
1836         rc = discipline->check_device(device);
1837         if (rc) {
1838                 printk (KERN_WARNING
1839                         "dasd_generic couldn't online device %s "
1840                         "with discipline %s\n",
1841                         cdev->dev.bus_id, discipline->name);
1842                 dasd_delete_device(device);
1843                 return rc;
1844         }
1845
1846         dasd_set_target_state(device, DASD_STATE_ONLINE);
1847         if (device->state <= DASD_STATE_KNOWN) {
1848                 printk (KERN_WARNING
1849                         "dasd_generic discipline not found for %s\n",
1850                         cdev->dev.bus_id);
1851                 rc = -ENODEV;
1852                 dasd_set_target_state(device, DASD_STATE_NEW);
1853                 dasd_delete_device(device);
1854         } else
1855                 pr_debug("dasd_generic device %s found\n",
1856                                 cdev->dev.bus_id);
1857
1858         /* FIXME: we have to wait for the root device but we don't want
1859          * to wait for each single device but for all at once. */
1860         wait_event(dasd_init_waitq, _wait_for_device(device));
1861
1862         dasd_put_device(device);
1863
1864         return rc;
1865 }
1866
1867 int
1868 dasd_generic_set_offline (struct ccw_device *cdev)
1869 {
1870         struct dasd_device *device;
1871         int max_count;
1872
1873         device = dasd_device_from_cdev(cdev);
1874         if (IS_ERR(device))
1875                 return PTR_ERR(device);
1876         if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
1877                 /* Already doing offline processing */
1878                 dasd_put_device(device);
1879                 return 0;
1880         }
1881         /*
1882          * We must make sure that this device is currently not in use.
1883          * The open_count is increased for every opener, that includes
1884          * the blkdev_get in dasd_scan_partitions. We are only interested
1885          * in the other openers.
1886          */
1887         max_count = device->bdev ? 0 : -1;
1888         if (atomic_read(&device->open_count) > max_count) {
1889                 printk (KERN_WARNING "Can't offline dasd device with open"
1890                         " count = %i.\n",
1891                         atomic_read(&device->open_count));
1892                 clear_bit(DASD_FLAG_OFFLINE, &device->flags);
1893                 dasd_put_device(device);
1894                 return -EBUSY;
1895         }
1896         dasd_set_target_state(device, DASD_STATE_NEW);
1897         /* dasd_delete_device destroys the device reference. */
1898         dasd_delete_device(device);
1899
1900         return 0;
1901 }
1902
1903 int
1904 dasd_generic_notify(struct ccw_device *cdev, int event)
1905 {
1906         struct dasd_device *device;
1907         struct dasd_ccw_req *cqr;
1908         unsigned long flags;
1909         int ret;
1910
1911         device = dasd_device_from_cdev(cdev);
1912         if (IS_ERR(device))
1913                 return 0;
1914         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1915         ret = 0;
1916         switch (event) {
1917         case CIO_GONE:
1918         case CIO_NO_PATH:
1919                 if (device->state < DASD_STATE_BASIC)
1920                         break;
1921                 /* Device is active. We want to keep it. */
1922                 if (test_bit(DASD_FLAG_DSC_ERROR, &device->flags)) {
1923                         list_for_each_entry(cqr, &device->ccw_queue, list)
1924                                 if (cqr->status == DASD_CQR_IN_IO)
1925                                         cqr->status = DASD_CQR_FAILED;
1926                         device->stopped |= DASD_STOPPED_DC_EIO;
1927                         dasd_schedule_bh(device);
1928                 } else {
1929                         list_for_each_entry(cqr, &device->ccw_queue, list)
1930                                 if (cqr->status == DASD_CQR_IN_IO)
1931                                         cqr->status = DASD_CQR_QUEUED;
1932                         device->stopped |= DASD_STOPPED_DC_WAIT;
1933                         dasd_set_timer(device, 0);
1934                 }
1935                 ret = 1;
1936                 break;
1937         case CIO_OPER:
1938                 /* FIXME: add a sanity check. */
1939                 device->stopped &= ~(DASD_STOPPED_DC_WAIT|DASD_STOPPED_DC_EIO);
1940                 dasd_schedule_bh(device);
1941                 ret = 1;
1942                 break;
1943         }
1944         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1945         dasd_put_device(device);
1946         return ret;
1947 }
1948
1949 /*
1950  * Automatically online either all dasd devices (dasd_autodetect) or
1951  * all devices specified with dasd= parameters.
1952  */
1953 void
1954 dasd_generic_auto_online (struct ccw_driver *dasd_discipline_driver)
1955 {
1956         struct device_driver *drv;
1957         struct device *d, *dev;
1958         struct ccw_device *cdev;
1959
1960         drv = get_driver(&dasd_discipline_driver->driver);
1961         down_read(&drv->bus->subsys.rwsem);
1962         dev = NULL;
1963         list_for_each_entry(d, &drv->devices, driver_list) {
1964                 dev = get_device(d);
1965                 if (!dev)
1966                         continue;
1967                 cdev = to_ccwdev(dev);
1968                 if (dasd_autodetect || dasd_busid_known(cdev->dev.bus_id) == 0)
1969                         ccw_device_set_online(cdev);
1970                 put_device(dev);
1971         }
1972         up_read(&drv->bus->subsys.rwsem);
1973         put_driver(drv);
1974 }
1975
1976 static int __init
1977 dasd_init(void)
1978 {
1979         int rc;
1980
1981         init_waitqueue_head(&dasd_init_waitq);
1982
1983         /* register 'common' DASD debug area, used faor all DBF_XXX calls */
1984         dasd_debug_area = debug_register("dasd", 0, 2, 8 * sizeof (long));
1985         if (dasd_debug_area == NULL) {
1986                 rc = -ENOMEM;
1987                 goto failed;
1988         }
1989         debug_register_view(dasd_debug_area, &debug_hex_ascii_view);
1990         debug_set_level(dasd_debug_area, DBF_ERR);
1991
1992         DBF_EVENT(DBF_EMERG, "%s", "debug area created");
1993
1994         dasd_diag_discipline_pointer = NULL;
1995
1996         rc = devfs_mk_dir("dasd");
1997         if (rc)
1998                 goto failed;
1999         rc = dasd_devmap_init();
2000         if (rc)
2001                 goto failed;
2002         rc = dasd_gendisk_init();
2003         if (rc)
2004                 goto failed;
2005         rc = dasd_parse();
2006         if (rc)
2007                 goto failed;
2008         rc = dasd_ioctl_init();
2009         if (rc)
2010                 goto failed;
2011 #ifdef CONFIG_PROC_FS
2012         rc = dasd_proc_init();
2013         if (rc)
2014                 goto failed;
2015 #endif
2016
2017         return 0;
2018 failed:
2019         MESSAGE(KERN_INFO, "%s", "initialization not performed due to errors");
2020         dasd_exit();
2021         return rc;
2022 }
2023
2024 module_init(dasd_init);
2025 module_exit(dasd_exit);
2026
2027 EXPORT_SYMBOL(dasd_debug_area);
2028 EXPORT_SYMBOL(dasd_diag_discipline_pointer);
2029
2030 EXPORT_SYMBOL(dasd_add_request_head);
2031 EXPORT_SYMBOL(dasd_add_request_tail);
2032 EXPORT_SYMBOL(dasd_cancel_req);
2033 EXPORT_SYMBOL(dasd_clear_timer);
2034 EXPORT_SYMBOL(dasd_enable_device);
2035 EXPORT_SYMBOL(dasd_int_handler);
2036 EXPORT_SYMBOL(dasd_kfree_request);
2037 EXPORT_SYMBOL(dasd_kick_device);
2038 EXPORT_SYMBOL(dasd_kmalloc_request);
2039 EXPORT_SYMBOL(dasd_schedule_bh);
2040 EXPORT_SYMBOL(dasd_set_target_state);
2041 EXPORT_SYMBOL(dasd_set_timer);
2042 EXPORT_SYMBOL(dasd_sfree_request);
2043 EXPORT_SYMBOL(dasd_sleep_on);
2044 EXPORT_SYMBOL(dasd_sleep_on_immediatly);
2045 EXPORT_SYMBOL(dasd_sleep_on_interruptible);
2046 EXPORT_SYMBOL(dasd_smalloc_request);
2047 EXPORT_SYMBOL(dasd_start_IO);
2048 EXPORT_SYMBOL(dasd_term_IO);
2049
2050 EXPORT_SYMBOL_GPL(dasd_generic_probe);
2051 EXPORT_SYMBOL_GPL(dasd_generic_remove);
2052 EXPORT_SYMBOL_GPL(dasd_generic_notify);
2053 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
2054 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
2055 EXPORT_SYMBOL_GPL(dasd_generic_auto_online);
2056
2057 /*
2058  * Overrides for Emacs so that we follow Linus's tabbing style.
2059  * Emacs will notice this stuff at the end of the file and automatically
2060  * adjust the settings for this buffer only.  This must remain at the end
2061  * of the file.
2062  * ---------------------------------------------------------------------------
2063  * Local variables:
2064  * c-indent-level: 4
2065  * c-brace-imaginary-offset: 0
2066  * c-brace-offset: -4
2067  * c-argdecl-indent: 4
2068  * c-label-offset: -4
2069  * c-continued-statement-offset: 4
2070  * c-continued-brace-offset: 0
2071  * indent-tabs-mode: 1
2072  * tab-width: 8
2073  * End:
2074  */