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: 1.165 $
  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, 1, 2,
 180                                             8 * sizeof (long));
 181         debug_register_view(device->debug_area, &debug_sprintf_view);
 182         debug_set_level(device->debug_area, DBF_EMERG);
 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
 524         cqr = kmalloc(sizeof(struct dasd_ccw_req), GFP_ATOMIC);
 525         if (cqr == NULL)
 526                 return ERR_PTR(-ENOMEM);
 527         memset(cqr, 0, sizeof(struct dasd_ccw_req));
 528         cqr->cpaddr = NULL;
 529         if (cplength > 0) {
 530                 cqr->cpaddr = kmalloc(cplength*sizeof(struct ccw1),
 531                                       GFP_ATOMIC | GFP_DMA);
 532                 if (cqr->cpaddr == NULL) {
 533                         kfree(cqr);
 534                         return ERR_PTR(-ENOMEM);
 535                 }
 536                 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
 537         }
 538         cqr->data = NULL;
 539         if (datasize > 0) {
 540                 cqr->data = kmalloc(datasize, GFP_ATOMIC | GFP_DMA);
 541                 if (cqr->data == NULL) {
 542                         if (cqr->cpaddr != NULL)
 543                                 kfree(cqr->cpaddr);
 544                         kfree(cqr);
 545                         return ERR_PTR(-ENOMEM);
 546                 }
 547                 memset(cqr->data, 0, datasize);
 548         }
 549         strncpy((char *) &cqr->magic, magic, 4);
 550         ASCEBC((char *) &cqr->magic, 4);
 551         set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
 552         dasd_get_device(device);
 553         return cqr;
 554 }
 555
 556 struct dasd_ccw_req *
 557 dasd_smalloc_request(char *magic, int cplength, int datasize,
 558                    struct dasd_device * device)
 559 {
 560         unsigned long flags;
 561         struct dasd_ccw_req *cqr;
 562         char *data;
 563         int size;
 564
 565         /* Sanity checks */
 566         if ( magic == NULL || datasize > PAGE_SIZE ||
 567              (cplength*sizeof(struct ccw1)) > PAGE_SIZE)
 568                 BUG();
 569
 570         size = (sizeof(struct dasd_ccw_req) + 7L) & -8L;
 571         if (cplength > 0)
 572                 size += cplength * sizeof(struct ccw1);
 573         if (datasize > 0)
 574                 size += datasize;
 575         spin_lock_irqsave(&device->mem_lock, flags);
 576         cqr = (struct dasd_ccw_req *)
 577                 dasd_alloc_chunk(&device->ccw_chunks, size);
 578         spin_unlock_irqrestore(&device->mem_lock, flags);
 579         if (cqr == NULL)
 580                 return ERR_PTR(-ENOMEM);
 581         memset(cqr, 0, sizeof(struct dasd_ccw_req));
 582         data = (char *) cqr + ((sizeof(struct dasd_ccw_req) + 7L) & -8L);
 583         cqr->cpaddr = NULL;
 584         if (cplength > 0) {
 585                 cqr->cpaddr = (struct ccw1 *) data;
 586                 data += cplength*sizeof(struct ccw1);
 587                 memset(cqr->cpaddr, 0, cplength*sizeof(struct ccw1));
 588         }
 589         cqr->data = NULL;
 590         if (datasize > 0) {
 591                 cqr->data = data;
 592                 memset(cqr->data, 0, datasize);
 593         }
 594         strncpy((char *) &cqr->magic, magic, 4);
 595         ASCEBC((char *) &cqr->magic, 4);
 596         set_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags);
 597         dasd_get_device(device);
 598         return cqr;
 599 }
 600
 601 /*
 602  * Free memory of a channel program. This function needs to free all the
 603  * idal lists that might have been created by dasd_set_cda and the
 604  * struct dasd_ccw_req itself.
 605  */
 606 void
 607 dasd_kfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
 608 {
 609 #ifdef CONFIG_ARCH_S390X
 610         struct ccw1 *ccw;
 611
 612         /* Clear any idals used for the request. */
 613         ccw = cqr->cpaddr;
 614         do {
 615                 clear_normalized_cda(ccw);
 616         } while (ccw++->flags & (CCW_FLAG_CC | CCW_FLAG_DC));
 617 #endif
 618         if (cqr->cpaddr != NULL)
 619                 kfree(cqr->cpaddr);
 620         if (cqr->data != NULL)
 621                 kfree(cqr->data);
 622         kfree(cqr);
 623         dasd_put_device(device);
 624 }
 625
 626 void
 627 dasd_sfree_request(struct dasd_ccw_req * cqr, struct dasd_device * device)
 628 {
 629         unsigned long flags;
 630
 631         spin_lock_irqsave(&device->mem_lock, flags);
 632         dasd_free_chunk(&device->ccw_chunks, cqr);
 633         spin_unlock_irqrestore(&device->mem_lock, flags);
 634         dasd_put_device(device);
 635 }
 636
 637 /*
 638  * Check discipline magic in cqr.
 639  */
 640 static inline int
 641 dasd_check_cqr(struct dasd_ccw_req *cqr)
 642 {
 643         struct dasd_device *device;
 644
 645         if (cqr == NULL)
 646                 return -EINVAL;
 647         device = cqr->device;
 648         if (strncmp((char *) &cqr->magic, device->discipline->ebcname, 4)) {
 649                 DEV_MESSAGE(KERN_WARNING, device,
 650                             " dasd_ccw_req 0x%08x magic doesn't match"
 651                             " discipline 0x%08x",
 652                             cqr->magic,
 653                             *(unsigned int *) device->discipline->name);
 654                 return -EINVAL;
 655         }
 656         return 0;
 657 }
 658
 659 /*
 660  * Terminate the current i/o and set the request to clear_pending.
 661  * Timer keeps device runnig.
 662  * ccw_device_clear can fail if the i/o subsystem
 663  * is in a bad mood.
 664  */
 665 int
 666 dasd_term_IO(struct dasd_ccw_req * cqr)
 667 {
 668         struct dasd_device *device;
 669         int retries, rc;
 670
 671         /* Check the cqr */
 672         rc = dasd_check_cqr(cqr);
 673         if (rc)
 674                 return rc;
 675         retries = 0;
 676         device = (struct dasd_device *) cqr->device;
 677         while ((retries < 5) && (cqr->status == DASD_CQR_IN_IO)) {
 678                 rc = ccw_device_clear(device->cdev, (long) cqr);
 679                 switch (rc) {
 680                 case 0: /* termination successful */
 681                         if (cqr->retries > 0) {
 682                                 cqr->retries--;
 683                                 cqr->status = DASD_CQR_CLEAR;
 684                         } else
 685                                 cqr->status = DASD_CQR_FAILED;
 686                         cqr->stopclk = get_clock();
 687                         DBF_DEV_EVENT(DBF_DEBUG, device,
 688                                       "terminate cqr %p successful",
 689                                       cqr);
 690                         break;
 691                 case -ENODEV:
 692                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
 693                                       "device gone, retry");
 694                         break;
 695                 case -EIO:
 696                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
 697                                       "I/O error, retry");
 698                         break;
 699                 case -EINVAL:
 700                 case -EBUSY:
 701                         DBF_DEV_EVENT(DBF_ERR, device, "%s",
 702                                       "device busy, retry later");
 703                         break;
 704                 default:
 705                         DEV_MESSAGE(KERN_ERR, device,
 706                                     "line %d unknown RC=%d, please "
 707                                     "report to linux390@de.ibm.com",
 708                                     __LINE__, rc);
 709                         BUG();
 710                         break;
 711                 }
 712                 retries++;
 713         }
 714         dasd_schedule_bh(device);
 715         return rc;
 716 }
 717
 718 /*
 719  * Start the i/o. This start_IO can fail if the channel is really busy.
 720  * In that case set up a timer to start the request later.
 721  */
 722 int
 723 dasd_start_IO(struct dasd_ccw_req * cqr)
 724 {
 725         struct dasd_device *device;
 726         int rc;
 727
 728         /* Check the cqr */
 729         rc = dasd_check_cqr(cqr);
 730         if (rc)
 731                 return rc;
 732         device = (struct dasd_device *) cqr->device;
 733         if (cqr->retries < 0) {
 734                 DEV_MESSAGE(KERN_DEBUG, device,
 735                             "start_IO: request %p (%02x/%i) - no retry left.",
 736                             cqr, cqr->status, cqr->retries);
 737                 cqr->status = DASD_CQR_FAILED;
 738                 return -EIO;
 739         }
 740         cqr->startclk = get_clock();
 741         cqr->starttime = jiffies;
 742         cqr->retries--;
 743         rc = ccw_device_start(device->cdev, cqr->cpaddr, (long) cqr,
 744                               cqr->lpm, 0);
 745         switch (rc) {
 746         case 0:
 747                 cqr->status = DASD_CQR_IN_IO;
 748                 DBF_DEV_EVENT(DBF_DEBUG, device,
 749                               "start_IO: request %p started successful",
 750                               cqr);
 751                 break;
 752         case -EBUSY:
 753                 DBF_DEV_EVENT(DBF_ERR, device, "%s",
 754                               "start_IO: device busy, retry later");
 755                 break;
 756         case -ETIMEDOUT:
 757                 DBF_DEV_EVENT(DBF_ERR, device, "%s",
 758                               "start_IO: request timeout, retry later");
 759                 break;
 760         case -EACCES:
 761                 /* -EACCES indicates that the request used only a
 762                  * subset of the available pathes and all these
 763                  * pathes are gone.
 764                  * Do a retry with all available pathes.
 765                  */
 766                 cqr->lpm = LPM_ANYPATH;
 767                 DBF_DEV_EVENT(DBF_ERR, device, "%s",
 768                               "start_IO: selected pathes gone,"
 769                               " retry on all pathes");
 770                 break;
 771         case -ENODEV:
 772         case -EIO:
 773                 DBF_DEV_EVENT(DBF_ERR, device, "%s",
 774                               "start_IO: device gone, retry");
 775                 break;
 776         default:
 777                 DEV_MESSAGE(KERN_ERR, device,
 778                             "line %d unknown RC=%d, please report"
 779                             " to linux390@de.ibm.com", __LINE__, rc);
 780                 BUG();
 781                 break;
 782         }
 783         return rc;
 784 }
 785
 786 /*
 787  * Timeout function for dasd devices. This is used for different purposes
 788  *  1) missing interrupt handler for normal operation
 789  *  2) delayed start of request where start_IO failed with -EBUSY
 790  *  3) timeout for missing state change interrupts
 791  * The head of the ccw queue will have status DASD_CQR_IN_IO for 1),
 792  * DASD_CQR_QUEUED for 2) and 3).
 793  */
 794 static void
 795 dasd_timeout_device(unsigned long ptr)
 796 {
 797         unsigned long flags;
 798         struct dasd_device *device;
 799
 800         device = (struct dasd_device *) ptr;
 801         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
 802         /* re-activate request queue */
 803         device->stopped &= ~DASD_STOPPED_PENDING;
 804         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
 805         dasd_schedule_bh(device);
 806 }
 807
 808 /*
 809  * Setup timeout for a device in jiffies.
 810  */
 811 void
 812 dasd_set_timer(struct dasd_device *device, int expires)
 813 {
 814         if (expires == 0) {
 815                 if (timer_pending(&device->timer))
 816                         del_timer(&device->timer);
 817                 return;
 818         }
 819         if (timer_pending(&device->timer)) {
 820                 if (mod_timer(&device->timer, jiffies + expires))
 821                         return;
 822         }
 823         device->timer.function = dasd_timeout_device;
 824         device->timer.data = (unsigned long) device;
 825         device->timer.expires = jiffies + expires;
 826         add_timer(&device->timer);
 827 }
 828
 829 /*
 830  * Clear timeout for a device.
 831  */
 832 void
 833 dasd_clear_timer(struct dasd_device *device)
 834 {
 835         if (timer_pending(&device->timer))
 836                 del_timer(&device->timer);
 837 }
 838
 839 static void
 840 dasd_handle_killed_request(struct ccw_device *cdev, unsigned long intparm)
 841 {
 842         struct dasd_ccw_req *cqr;
 843         struct dasd_device *device;
 844
 845         cqr = (struct dasd_ccw_req *) intparm;
 846         if (cqr->status != DASD_CQR_IN_IO) {
 847                 MESSAGE(KERN_DEBUG,
 848                         "invalid status in handle_killed_request: "
 849                         "bus_id %s, status %02x",
 850                         cdev->dev.bus_id, cqr->status);
 851                 return;
 852         }
 853
 854         device = (struct dasd_device *) cqr->device;
 855         if (device == NULL ||
 856             device != dasd_device_from_cdev(cdev) ||
 857             strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 858                 MESSAGE(KERN_DEBUG, "invalid device in request: bus_id %s",
 859                         cdev->dev.bus_id);
 860                 return;
 861         }
 862
 863         /* Schedule request to be retried. */
 864         cqr->status = DASD_CQR_QUEUED;
 865
 866         dasd_clear_timer(device);
 867         dasd_schedule_bh(device);
 868         dasd_put_device(device);
 869 }
 870
 871 static void
 872 dasd_handle_state_change_pending(struct dasd_device *device)
 873 {
 874         struct dasd_ccw_req *cqr;
 875         struct list_head *l, *n;
 876
 877         device->stopped &= ~DASD_STOPPED_PENDING;
 878
 879         /* restart all 'running' IO on queue */
 880         list_for_each_safe(l, n, &device->ccw_queue) {
 881                 cqr = list_entry(l, struct dasd_ccw_req, list);
 882                 if (cqr->status == DASD_CQR_IN_IO) {
 883                         cqr->status = DASD_CQR_QUEUED;
 884                 }
 885         }
 886         dasd_clear_timer(device);
 887         dasd_schedule_bh(device);
 888 }
 889
 890 /*
 891  * Interrupt handler for "normal" ssch-io based dasd devices.
 892  */
 893 void
 894 dasd_int_handler(struct ccw_device *cdev, unsigned long intparm,
 895                  struct irb *irb)
 896 {
 897         struct dasd_ccw_req *cqr, *next;
 898         struct dasd_device *device;
 899         unsigned long long now;
 900         int expires;
 901         dasd_era_t era;
 902         char mask;
 903
 904         if (IS_ERR(irb)) {
 905                 switch (PTR_ERR(irb)) {
 906                 case -EIO:
 907                         dasd_handle_killed_request(cdev, intparm);
 908                         break;
 909                 case -ETIMEDOUT:
 910                         printk(KERN_WARNING"%s(%s): request timed out\n",
 911                                __FUNCTION__, cdev->dev.bus_id);
 912                         //FIXME - dasd uses own timeout interface...
 913                         break;
 914                 default:
 915                         printk(KERN_WARNING"%s(%s): unknown error %ld\n",
 916                                __FUNCTION__, cdev->dev.bus_id, PTR_ERR(irb));
 917                 }
 918                 return;
 919         }
 920
 921         now = get_clock();
 922
 923         DBF_EVENT(DBF_ERR, "Interrupt: bus_id %s CS/DS %04x ip %08x",
 924                   cdev->dev.bus_id, ((irb->scsw.cstat<<8)|irb->scsw.dstat),
 925                   (unsigned int) intparm);
 926
 927         /* first of all check for state change pending interrupt */
 928         mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
 929         if ((irb->scsw.dstat & mask) == mask) {
 930                 device = dasd_device_from_cdev(cdev);
 931                 if (!IS_ERR(device)) {
 932                         dasd_handle_state_change_pending(device);
 933                         dasd_put_device(device);
 934                 }
 935                 return;
 936         }
 937
 938         cqr = (struct dasd_ccw_req *) intparm;
 939
 940         /* check for unsolicited interrupts */
 941         if (cqr == NULL) {
 942                 MESSAGE(KERN_DEBUG,
 943                         "unsolicited interrupt received: bus_id %s",
 944                         cdev->dev.bus_id);
 945                 return;
 946         }
 947
 948         device = (struct dasd_device *) cqr->device;
 949         if (device == NULL ||
 950             strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
 951                 MESSAGE(KERN_DEBUG, "invalid device in request: bus_id %s",
 952                         cdev->dev.bus_id);
 953                 return;
 954         }
 955
 956         /* Check for clear pending */
 957         if (cqr->status == DASD_CQR_CLEAR &&
 958             irb->scsw.fctl & SCSW_FCTL_CLEAR_FUNC) {
 959                 cqr->status = DASD_CQR_QUEUED;
 960                 dasd_clear_timer(device);
 961                 dasd_schedule_bh(device);
 962                 return;
 963         }
 964
 965         /* check status - the request might have been killed by dyn detach */
 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         DBF_DEV_EVENT(DBF_DEBUG, device, "Int: CS/DS 0x%04x for cqr %p",
 973                       ((irb->scsw.cstat << 8) | irb->scsw.dstat), cqr);
 974
 975         /* Find out the appropriate era_action. */
 976         if (irb->scsw.fctl & SCSW_FCTL_HALT_FUNC)
 977                 era = dasd_era_fatal;
 978         else if (irb->scsw.dstat == (DEV_STAT_CHN_END | DEV_STAT_DEV_END) &&
 979                  irb->scsw.cstat == 0 &&
 980                  !irb->esw.esw0.erw.cons)
 981                 era = dasd_era_none;
 982         else if (!test_bit(DASD_CQR_FLAGS_USE_ERP, &cqr->flags))
 983                 era = dasd_era_fatal; /* don't recover this request */
 984         else if (irb->esw.esw0.erw.cons)
 985                 era = device->discipline->examine_error(cqr, irb);
 986         else
 987                 era = dasd_era_recover;
 988
 989         DBF_DEV_EVENT(DBF_DEBUG, device, "era_code %d", era);
 990         expires = 0;
 991         if (era == dasd_era_none) {
 992                 cqr->status = DASD_CQR_DONE;
 993                 cqr->stopclk = now;
 994                 /* Start first request on queue if possible -> fast_io. */
 995                 if (cqr->list.next != &device->ccw_queue) {
 996                         next = list_entry(cqr->list.next,
 997                                           struct dasd_ccw_req, list);
 998                         if ((next->status == DASD_CQR_QUEUED) &&
 999                             (!device->stopped)) {
1000                                 if (device->discipline->start_IO(next) == 0)
1001                                         expires = next->expires;
1002                                 else
1003                                         DEV_MESSAGE(KERN_DEBUG, device, "%s",
1004                                                     "Interrupt fastpath "
1005                                                     "failed!");
1006                         }
1007                 }
1008         } else {                /* error */
1009                 memcpy(&cqr->irb, irb, sizeof (struct irb));
1010 #ifdef ERP_DEBUG
1011                 /* dump sense data */
1012                 dasd_log_sense(cqr, irb);
1013 #endif
1014                 switch (era) {
1015                 case dasd_era_fatal:
1016                         cqr->status = DASD_CQR_FAILED;
1017                         cqr->stopclk = now;
1018                         break;
1019                 case dasd_era_recover:
1020                         cqr->status = DASD_CQR_ERROR;
1021                         break;
1022                 default:
1023                         BUG();
1024                 }
1025         }
1026         if (expires != 0)
1027                 dasd_set_timer(device, expires);
1028         else
1029                 dasd_clear_timer(device);
1030         dasd_schedule_bh(device);
1031 }
1032
1033 /*
1034  * posts the buffer_cache about a finalized request
1035  */
1036 static inline void
1037 dasd_end_request(struct request *req, int uptodate)
1038 {
1039         if (end_that_request_first(req, uptodate, req->hard_nr_sectors))
1040                 BUG();
1041         add_disk_randomness(req->rq_disk);
1042         end_that_request_last(req);
1043 }
1044
1045 /*
1046  * Process finished error recovery ccw.
1047  */
1048 static inline void
1049 __dasd_process_erp(struct dasd_device *device, struct dasd_ccw_req *cqr)
1050 {
1051         dasd_erp_fn_t erp_fn;
1052
1053         if (cqr->status == DASD_CQR_DONE)
1054                 DBF_DEV_EVENT(DBF_NOTICE, device, "%s", "ERP successful");
1055         else
1056                 DEV_MESSAGE(KERN_ERR, device, "%s", "ERP unsuccessful");
1057         erp_fn = device->discipline->erp_postaction(cqr);
1058         erp_fn(cqr);
1059 }
1060
1061 /*
1062  * Process ccw request queue.
1063  */
1064 static inline void
1065 __dasd_process_ccw_queue(struct dasd_device * device,
1066                          struct list_head *final_queue)
1067 {
1068         struct list_head *l, *n;
1069         struct dasd_ccw_req *cqr;
1070         dasd_erp_fn_t erp_fn;
1071
1072 restart:
1073         /* Process request with final status. */
1074         list_for_each_safe(l, n, &device->ccw_queue) {
1075                 cqr = list_entry(l, struct dasd_ccw_req, list);
1076                 /* Stop list processing at the first non-final request. */
1077                 if (cqr->status != DASD_CQR_DONE &&
1078                     cqr->status != DASD_CQR_FAILED &&
1079                     cqr->status != DASD_CQR_ERROR)
1080                         break;
1081                 /*  Process requests with DASD_CQR_ERROR */
1082                 if (cqr->status == DASD_CQR_ERROR) {
1083                         if (cqr->irb.scsw.fctl & SCSW_FCTL_HALT_FUNC) {
1084                                 cqr->status = DASD_CQR_FAILED;
1085                                 cqr->stopclk = get_clock();
1086                         } else {
1087                                 if (cqr->irb.esw.esw0.erw.cons) {
1088                                         erp_fn = device->discipline->
1089                                                 erp_action(cqr);
1090                                         erp_fn(cqr);
1091                                 } else
1092                                         dasd_default_erp_action(cqr);
1093                         }
1094                         goto restart;
1095                 }
1096                 /* Process finished ERP request. */
1097                 if (cqr->refers) {
1098                         __dasd_process_erp(device, cqr);
1099                         goto restart;
1100                 }
1101
1102                 /* Rechain finished requests to final queue */
1103                 cqr->endclk = get_clock();
1104                 list_move_tail(&cqr->list, final_queue);
1105         }
1106 }
1107
1108 static void
1109 dasd_end_request_cb(struct dasd_ccw_req * cqr, void *data)
1110 {
1111         struct request *req;
1112         struct dasd_device *device;
1113         int status;
1114
1115         req = (struct request *) data;
1116         device = cqr->device;
1117         dasd_profile_end(device, cqr, req);
1118         status = cqr->device->discipline->free_cp(cqr,req);
1119         spin_lock_irq(&device->request_queue_lock);
1120         dasd_end_request(req, status);
1121         spin_unlock_irq(&device->request_queue_lock);
1122 }
1123
1124
1125 /*
1126  * Fetch requests from the block device queue.
1127  */
1128 static inline void
1129 __dasd_process_blk_queue(struct dasd_device * device)
1130 {
1131         request_queue_t *queue;
1132         struct request *req;
1133         struct dasd_ccw_req *cqr;
1134         int nr_queued, feature_ro;
1135
1136         queue = device->request_queue;
1137         /* No queue ? Then there is nothing to do. */
1138         if (queue == NULL)
1139                 return;
1140
1141         feature_ro = dasd_get_feature(device->cdev, DASD_FEATURE_READONLY);
1142         if (feature_ro < 0)     /* no devmap */
1143                 return;
1144
1145         /*
1146          * We requeue request from the block device queue to the ccw
1147          * queue only in two states. In state DASD_STATE_READY the
1148          * partition detection is done and we need to requeue requests
1149          * for that. State DASD_STATE_ONLINE is normal block device
1150          * operation.
1151          */
1152         if (device->state != DASD_STATE_READY &&
1153             device->state != DASD_STATE_ONLINE)
1154                 return;
1155         nr_queued = 0;
1156         /* Now we try to fetch requests from the request queue */
1157         list_for_each_entry(cqr, &device->ccw_queue, list)
1158                 if (cqr->status == DASD_CQR_QUEUED)
1159                         nr_queued++;
1160         while (!blk_queue_plugged(queue) &&
1161                elv_next_request(queue) &&
1162                 nr_queued < DASD_CHANQ_MAX_SIZE) {
1163                 req = elv_next_request(queue);
1164
1165                 if (feature_ro && rq_data_dir(req) == WRITE) {
1166                         DBF_DEV_EVENT(DBF_ERR, device,
1167                                       "Rejecting write request %p",
1168                                       req);
1169                         blkdev_dequeue_request(req);
1170                         dasd_end_request(req, 0);
1171                         continue;
1172                 }
1173                 if (device->stopped & DASD_STOPPED_DC_EIO) {
1174                         blkdev_dequeue_request(req);
1175                         dasd_end_request(req, 0);
1176                         continue;
1177                 }
1178                 cqr = device->discipline->build_cp(device, req);
1179                 if (IS_ERR(cqr)) {
1180                         if (PTR_ERR(cqr) == -ENOMEM)
1181                                 break;  /* terminate request queue loop */
1182                         DBF_DEV_EVENT(DBF_ERR, device,
1183                                       "CCW creation failed (rc=%ld) "
1184                                       "on request %p",
1185                                       PTR_ERR(cqr), req);
1186                         blkdev_dequeue_request(req);
1187                         dasd_end_request(req, 0);
1188                         continue;
1189                 }
1190                 cqr->callback = dasd_end_request_cb;
1191                 cqr->callback_data = (void *) req;
1192                 cqr->status = DASD_CQR_QUEUED;
1193                 blkdev_dequeue_request(req);
1194                 list_add_tail(&cqr->list, &device->ccw_queue);
1195                 dasd_profile_start(device, cqr, req);
1196                 nr_queued++;
1197         }
1198 }
1199
1200 /*
1201  * Take a look at the first request on the ccw queue and check
1202  * if it reached its expire time. If so, terminate the IO.
1203  */
1204 static inline void
1205 __dasd_check_expire(struct dasd_device * device)
1206 {
1207         struct dasd_ccw_req *cqr;
1208
1209         if (list_empty(&device->ccw_queue))
1210                 return;
1211         cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
1212         if (cqr->status == DASD_CQR_IN_IO && cqr->expires != 0) {
1213                 if (time_after_eq(jiffies, cqr->expires + cqr->starttime)) {
1214                         if (device->discipline->term_IO(cqr) != 0)
1215                                 /* Hmpf, try again in 1/10 sec */
1216                                 dasd_set_timer(device, 10);
1217                 }
1218         }
1219 }
1220
1221 /*
1222  * Take a look at the first request on the ccw queue and check
1223  * if it needs to be started.
1224  */
1225 static inline void
1226 __dasd_start_head(struct dasd_device * device)
1227 {
1228         struct dasd_ccw_req *cqr;
1229         int rc;
1230
1231         if (list_empty(&device->ccw_queue))
1232                 return;
1233         cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
1234         if ((cqr->status == DASD_CQR_QUEUED) &&
1235             (!device->stopped)) {
1236                 /* try to start the first I/O that can be started */
1237                 rc = device->discipline->start_IO(cqr);
1238                 if (rc == 0)
1239                         dasd_set_timer(device, cqr->expires);
1240                 else if (rc == -EACCES) {
1241                         dasd_schedule_bh(device);
1242                 } else
1243                         /* Hmpf, try again in 1/2 sec */
1244                         dasd_set_timer(device, 50);
1245         }
1246 }
1247
1248 /*
1249  * Remove requests from the ccw queue.
1250  */
1251 static void
1252 dasd_flush_ccw_queue(struct dasd_device * device, int all)
1253 {
1254         struct list_head flush_queue;
1255         struct list_head *l, *n;
1256         struct dasd_ccw_req *cqr;
1257
1258         INIT_LIST_HEAD(&flush_queue);
1259         spin_lock_irq(get_ccwdev_lock(device->cdev));
1260         list_for_each_safe(l, n, &device->ccw_queue) {
1261                 cqr = list_entry(l, struct dasd_ccw_req, list);
1262                 /* Flush all request or only block device requests? */
1263                 if (all == 0 && cqr->callback == dasd_end_request_cb)
1264                         continue;
1265                 if (cqr->status == DASD_CQR_IN_IO)
1266                         device->discipline->term_IO(cqr);
1267                 if (cqr->status != DASD_CQR_DONE ||
1268                     cqr->status != DASD_CQR_FAILED) {
1269                         cqr->status = DASD_CQR_FAILED;
1270                         cqr->stopclk = get_clock();
1271                 }
1272                 /* Process finished ERP request. */
1273                 if (cqr->refers) {
1274                         __dasd_process_erp(device, cqr);
1275                         continue;
1276                 }
1277                 /* Rechain request on device request queue */
1278                 cqr->endclk = get_clock();
1279                 list_move_tail(&cqr->list, &flush_queue);
1280         }
1281         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1282         /* Now call the callback function of flushed requests */
1283         list_for_each_safe(l, n, &flush_queue) {
1284                 cqr = list_entry(l, struct dasd_ccw_req, list);
1285                 if (cqr->callback != NULL)
1286                         (cqr->callback)(cqr, cqr->callback_data);
1287         }
1288 }
1289
1290 /*
1291  * Acquire the device lock and process queues for the device.
1292  */
1293 static void
1294 dasd_tasklet(struct dasd_device * device)
1295 {
1296         struct list_head final_queue;
1297         struct list_head *l, *n;
1298         struct dasd_ccw_req *cqr;
1299
1300         atomic_set (&device->tasklet_scheduled, 0);
1301         INIT_LIST_HEAD(&final_queue);
1302         spin_lock_irq(get_ccwdev_lock(device->cdev));
1303         /* Check expire time of first request on the ccw queue. */
1304         __dasd_check_expire(device);
1305         /* Finish off requests on ccw queue */
1306         __dasd_process_ccw_queue(device, &final_queue);
1307         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1308         /* Now call the callback function of requests with final status */
1309         list_for_each_safe(l, n, &final_queue) {
1310                 cqr = list_entry(l, struct dasd_ccw_req, list);
1311                 list_del(&cqr->list);
1312                 if (cqr->callback != NULL)
1313                         (cqr->callback)(cqr, cqr->callback_data);
1314         }
1315         spin_lock_irq(&device->request_queue_lock);
1316         spin_lock(get_ccwdev_lock(device->cdev));
1317         /* Get new request from the block device request queue */
1318         __dasd_process_blk_queue(device);
1319         /* Now check if the head of the ccw queue needs to be started. */
1320         __dasd_start_head(device);
1321         spin_unlock(get_ccwdev_lock(device->cdev));
1322         spin_unlock_irq(&device->request_queue_lock);
1323         dasd_put_device(device);
1324 }
1325
1326 /*
1327  * Schedules a call to dasd_tasklet over the device tasklet.
1328  */
1329 void
1330 dasd_schedule_bh(struct dasd_device * device)
1331 {
1332         /* Protect against rescheduling. */
1333         if (atomic_compare_and_swap (0, 1, &device->tasklet_scheduled))
1334                 return;
1335         dasd_get_device(device);
1336         tasklet_hi_schedule(&device->tasklet);
1337 }
1338
1339 /*
1340  * Queue a request to the head of the ccw_queue. Start the I/O if
1341  * possible.
1342  */
1343 void
1344 dasd_add_request_head(struct dasd_ccw_req *req)
1345 {
1346         struct dasd_device *device;
1347         unsigned long flags;
1348
1349         device = req->device;
1350         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1351         req->status = DASD_CQR_QUEUED;
1352         req->device = device;
1353         list_add(&req->list, &device->ccw_queue);
1354         /* let the bh start the request to keep them in order */
1355         dasd_schedule_bh(device);
1356         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1357 }
1358
1359 /*
1360  * Queue a request to the tail of the ccw_queue. Start the I/O if
1361  * possible.
1362  */
1363 void
1364 dasd_add_request_tail(struct dasd_ccw_req *req)
1365 {
1366         struct dasd_device *device;
1367         unsigned long flags;
1368
1369         device = req->device;
1370         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1371         req->status = DASD_CQR_QUEUED;
1372         req->device = device;
1373         list_add_tail(&req->list, &device->ccw_queue);
1374         /* let the bh start the request to keep them in order */
1375         dasd_schedule_bh(device);
1376         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1377 }
1378
1379 /*
1380  * Wakeup callback.
1381  */
1382 static void
1383 dasd_wakeup_cb(struct dasd_ccw_req *cqr, void *data)
1384 {
1385         wake_up((wait_queue_head_t *) data);
1386 }
1387
1388 static inline int
1389 _wait_for_wakeup(struct dasd_ccw_req *cqr)
1390 {
1391         struct dasd_device *device;
1392         int rc;
1393
1394         device = cqr->device;
1395         spin_lock_irq(get_ccwdev_lock(device->cdev));
1396         rc = cqr->status == DASD_CQR_DONE || cqr->status == DASD_CQR_FAILED;
1397         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1398         return rc;
1399 }
1400
1401 /*
1402  * Attempts to start a special ccw queue and waits for its completion.
1403  */
1404 int
1405 dasd_sleep_on(struct dasd_ccw_req * cqr)
1406 {
1407         wait_queue_head_t wait_q;
1408         struct dasd_device *device;
1409         int rc;
1410
1411         device = cqr->device;
1412         spin_lock_irq(get_ccwdev_lock(device->cdev));
1413
1414         init_waitqueue_head (&wait_q);
1415         cqr->callback = dasd_wakeup_cb;
1416         cqr->callback_data = (void *) &wait_q;
1417         cqr->status = DASD_CQR_QUEUED;
1418         list_add_tail(&cqr->list, &device->ccw_queue);
1419
1420         /* let the bh start the request to keep them in order */
1421         dasd_schedule_bh(device);
1422
1423         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1424
1425         wait_event(wait_q, _wait_for_wakeup(cqr));
1426
1427         /* Request status is either done or failed. */
1428         rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
1429         return rc;
1430 }
1431
1432 /*
1433  * Attempts to start a special ccw queue and wait interruptible
1434  * for its completion.
1435  */
1436 int
1437 dasd_sleep_on_interruptible(struct dasd_ccw_req * cqr)
1438 {
1439         wait_queue_head_t wait_q;
1440         struct dasd_device *device;
1441         int rc, finished;
1442
1443         device = cqr->device;
1444         spin_lock_irq(get_ccwdev_lock(device->cdev));
1445
1446         init_waitqueue_head (&wait_q);
1447         cqr->callback = dasd_wakeup_cb;
1448         cqr->callback_data = (void *) &wait_q;
1449         cqr->status = DASD_CQR_QUEUED;
1450         list_add_tail(&cqr->list, &device->ccw_queue);
1451
1452         /* let the bh start the request to keep them in order */
1453         dasd_schedule_bh(device);
1454         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1455
1456         finished = 0;
1457         while (!finished) {
1458                 rc = wait_event_interruptible(wait_q, _wait_for_wakeup(cqr));
1459                 if (rc != -ERESTARTSYS) {
1460                         /* Request status is either done or failed. */
1461                         rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
1462                         break;
1463                 }
1464                 spin_lock_irq(get_ccwdev_lock(device->cdev));
1465                 if (cqr->status == DASD_CQR_IN_IO &&
1466                     device->discipline->term_IO(cqr) == 0) {
1467                         list_del(&cqr->list);
1468                         finished = 1;
1469                 }
1470                 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1471         }
1472         return rc;
1473 }
1474
1475 /*
1476  * Whoa nelly now it gets really hairy. For some functions (e.g. steal lock
1477  * for eckd devices) the currently running request has to be terminated
1478  * and be put back to status queued, before the special request is added
1479  * to the head of the queue. Then the special request is waited on normally.
1480  */
1481 static inline int
1482 _dasd_term_running_cqr(struct dasd_device *device)
1483 {
1484         struct dasd_ccw_req *cqr;
1485         int rc;
1486
1487         if (list_empty(&device->ccw_queue))
1488                 return 0;
1489         cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, list);
1490         rc = device->discipline->term_IO(cqr);
1491         if (rc == 0) {
1492                 /* termination successful */
1493                 cqr->status = DASD_CQR_QUEUED;
1494                 cqr->startclk = cqr->stopclk = 0;
1495                 cqr->starttime = 0;
1496         }
1497         return rc;
1498 }
1499
1500 int
1501 dasd_sleep_on_immediatly(struct dasd_ccw_req * cqr)
1502 {
1503         wait_queue_head_t wait_q;
1504         struct dasd_device *device;
1505         int rc;
1506
1507         device = cqr->device;
1508         spin_lock_irq(get_ccwdev_lock(device->cdev));
1509         rc = _dasd_term_running_cqr(device);
1510         if (rc) {
1511                 spin_unlock_irq(get_ccwdev_lock(device->cdev));
1512                 return rc;
1513         }
1514
1515         init_waitqueue_head (&wait_q);
1516         cqr->callback = dasd_wakeup_cb;
1517         cqr->callback_data = (void *) &wait_q;
1518         cqr->status = DASD_CQR_QUEUED;
1519         list_add(&cqr->list, &device->ccw_queue);
1520
1521         /* let the bh start the request to keep them in order */
1522         dasd_schedule_bh(device);
1523
1524         spin_unlock_irq(get_ccwdev_lock(device->cdev));
1525
1526         wait_event(wait_q, _wait_for_wakeup(cqr));
1527
1528         /* Request status is either done or failed. */
1529         rc = (cqr->status == DASD_CQR_FAILED) ? -EIO : 0;
1530         return rc;
1531 }
1532
1533 /*
1534  * Cancels a request that was started with dasd_sleep_on_req.
1535  * This is useful to timeout requests. The request will be
1536  * terminated if it is currently in i/o.
1537  * Returns 1 if the request has been terminated.
1538  */
1539 int
1540 dasd_cancel_req(struct dasd_ccw_req *cqr)
1541 {
1542         struct dasd_device *device = cqr->device;
1543         unsigned long flags;
1544         int rc;
1545
1546         rc = 0;
1547         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
1548         switch (cqr->status) {
1549         case DASD_CQR_QUEUED:
1550                 /* request was not started - just set to failed */
1551                 cqr->status = DASD_CQR_FAILED;
1552                 break;
1553         case DASD_CQR_IN_IO:
1554                 /* request in IO - terminate IO and release again */
1555                 if (device->discipline->term_IO(cqr) != 0)
1556                         /* what to do if unable to terminate ??????
1557                            e.g. not _IN_IO */
1558                         cqr->status = DASD_CQR_FAILED;
1559                 cqr->stopclk = get_clock();
1560                 rc = 1;
1561                 break;
1562         case DASD_CQR_DONE:
1563         case DASD_CQR_FAILED:
1564                 /* already finished - do nothing */
1565                 break;
1566         default:
1567                 DEV_MESSAGE(KERN_ALERT, device,
1568                             "invalid status %02x in request",
1569                             cqr->status);
1570                 BUG();
1571
1572         }
1573         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
1574         dasd_schedule_bh(device);
1575         return rc;
1576 }
1577
1578 /*
1579  * SECTION: Block device operations (request queue, partitions, open, release).
1580  */
1581
1582 /*
1583  * Dasd request queue function. Called from ll_rw_blk.c
1584  */
1585 static void
1586 do_dasd_request(request_queue_t * queue)
1587 {
1588         struct dasd_device *device;
1589
1590         device = (struct dasd_device *) queue->queuedata;
1591         spin_lock(get_ccwdev_lock(device->cdev));
1592         /* Get new request from the block device request queue */
1593         __dasd_process_blk_queue(device);
1594         /* Now check if the head of the ccw queue needs to be started. */
1595         __dasd_start_head(device);
1596         spin_unlock(get_ccwdev_lock(device->cdev));
1597 }
1598
1599 /*
1600  * Allocate and initialize request queue and default I/O scheduler.
1601  */
1602 static int
1603 dasd_alloc_queue(struct dasd_device * device)
1604 {
1605         int rc;
1606
1607         device->request_queue = blk_init_queue(do_dasd_request,
1608                                                &device->request_queue_lock);
1609         if (device->request_queue == NULL)
1610                 return -ENOMEM;
1611
1612         device->request_queue->queuedata = device;
1613
1614         elevator_exit(device->request_queue->elevator);
1615         rc = elevator_init(device->request_queue, "deadline");
1616         if (rc) {
1617                 blk_cleanup_queue(device->request_queue);
1618                 return rc;
1619         }
1620         return 0;
1621 }
1622
1623 /*
1624  * Allocate and initialize request queue.
1625  */
1626 static void
1627 dasd_setup_queue(struct dasd_device * device)
1628 {
1629         int max;
1630
1631         blk_queue_hardsect_size(device->request_queue, device->bp_block);
1632         max = device->discipline->max_blocks << device->s2b_shift;
1633         blk_queue_max_sectors(device->request_queue, max);
1634         blk_queue_max_phys_segments(device->request_queue, -1L);
1635         blk_queue_max_hw_segments(device->request_queue, -1L);
1636         blk_queue_max_segment_size(device->request_queue, -1L);
1637         blk_queue_segment_boundary(device->request_queue, -1L);
1638         blk_queue_ordered(device->request_queue, 1);
1639 }
1640
1641 /*
1642  * Deactivate and free request queue.
1643  */
1644 static void
1645 dasd_free_queue(struct dasd_device * device)
1646 {
1647         if (device->request_queue) {
1648                 blk_cleanup_queue(device->request_queue);
1649                 device->request_queue = NULL;
1650         }
1651 }
1652
1653 /*
1654  * Flush request on the request queue.
1655  */
1656 static void
1657 dasd_flush_request_queue(struct dasd_device * device)
1658 {
1659         struct request *req;
1660
1661         if (!device->request_queue)
1662                 return;
1663
1664         spin_lock_irq(&device->request_queue_lock);
1665         while (!list_empty(&device->request_queue->queue_head)) {
1666                 req = elv_next_request(device->request_queue);
1667                 if (req == NULL)
1668                         break;
1669                 dasd_end_request(req, 0);
1670                 blkdev_dequeue_request(req);
1671         }
1672         spin_unlock_irq(&device->request_queue_lock);
1673 }
1674
1675 static int
1676 dasd_open(struct inode *inp, struct file *filp)
1677 {
1678         struct gendisk *disk = inp->i_bdev->bd_disk;
1679         struct dasd_device *device = disk->private_data;
1680         int rc;
1681
1682         atomic_inc(&device->open_count);
1683         if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
1684                 rc = -ENODEV;
1685                 goto unlock;
1686         }
1687
1688         if (!try_module_get(device->discipline->owner)) {
1689                 rc = -EINVAL;
1690                 goto unlock;
1691         }
1692
1693         if (dasd_probeonly) {
1694                 DEV_MESSAGE(KERN_INFO, device, "%s",
1695                             "No access to device due to probeonly mode");
1696                 rc = -EPERM;
1697                 goto out;
1698         }
1699
1700         if (device->state < DASD_STATE_BASIC) {
1701                 DBF_DEV_EVENT(DBF_ERR, device, " %s",
1702                               " Cannot open unrecognized device");
1703                 rc = -ENODEV;
1704                 goto out;
1705         }
1706
1707         return 0;
1708
1709 out:
1710         module_put(device->discipline->owner);
1711 unlock:
1712         atomic_dec(&device->open_count);
1713         return rc;
1714 }
1715
1716 static int
1717 dasd_release(struct inode *inp, struct file *filp)
1718 {
1719         struct gendisk *disk = inp->i_bdev->bd_disk;
1720         struct dasd_device *device = disk->private_data;
1721
1722         atomic_dec(&device->open_count);
1723         module_put(device->discipline->owner);
1724         return 0;
1725 }
1726
1727 struct block_device_operations
1728 dasd_device_operations = {
1729         .owner          = THIS_MODULE,
1730         .open           = dasd_open,
1731         .release        = dasd_release,
1732         .ioctl          = dasd_ioctl,
1733 };
1734
1735
1736 static void
1737 dasd_exit(void)
1738 {
1739 #ifdef CONFIG_PROC_FS
1740         dasd_proc_exit();
1741 #endif
1742         dasd_ioctl_exit();
1743         if (dasd_page_cache != NULL) {
1744                 kmem_cache_destroy(dasd_page_cache);
1745                 dasd_page_cache = NULL;
1746         }
1747         dasd_gendisk_exit();
1748         dasd_devmap_exit();
1749         devfs_remove("dasd");
1750         if (dasd_debug_area != NULL) {
1751                 debug_unregister(dasd_debug_area);
1752                 dasd_debug_area = NULL;
1753         }
1754 }
1755
1756 /*
1757  * SECTION: common functions for ccw_driver use
1758  */
1759
1760 /* initial attempt at a probe function. this can be simplified once
1761  * the other detection code is gone */
1762 int
1763 dasd_generic_probe (struct ccw_device *cdev,
1764                     struct dasd_discipline *discipline)
1765 {
1766         int ret;
1767
1768         ret = dasd_add_sysfs_files(cdev);
1769         if (ret) {
1770                 printk(KERN_WARNING
1771                        "dasd_generic_probe: could not add sysfs entries "
1772                        "for %s\n", cdev->dev.bus_id);
1773         } else {
1774                 cdev->handler = &dasd_int_handler;
1775         }
1776
1777         return ret;
1778 }
1779
1780 /* this will one day be called from a global not_oper handler.
1781  * It is also used by driver_unregister during module unload */
1782 void
1783 dasd_generic_remove (struct ccw_device *cdev)
1784 {
1785         struct dasd_device *device;
1786
1787         cdev->handler = NULL;
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 feature_diag, rc;
1818
1819         device = dasd_create_device(cdev);
1820         if (IS_ERR(device))
1821                 return PTR_ERR(device);
1822
1823         feature_diag = dasd_get_feature(cdev, DASD_FEATURE_USEDIAG);
1824         if (feature_diag < 0)
1825                 return feature_diag;
1826
1827         if (feature_diag) {
1828                 if (!dasd_diag_discipline_pointer) {
1829                         printk (KERN_WARNING
1830                                 "dasd_generic couldn't online device %s "
1831                                 "- discipline DIAG not available\n",
1832                                 cdev->dev.bus_id);
1833                         dasd_delete_device(device);
1834                         return -ENODEV;
1835                 }
1836                 discipline = dasd_diag_discipline_pointer;
1837         }
1838         device->discipline = discipline;
1839
1840         rc = discipline->check_device(device);
1841         if (rc) {
1842                 printk (KERN_WARNING
1843                         "dasd_generic couldn't online device %s "
1844                         "with discipline %s rc=%i\n",
1845                         cdev->dev.bus_id, discipline->name, rc);
1846                 dasd_delete_device(device);
1847                 return rc;
1848         }
1849
1850         dasd_set_target_state(device, DASD_STATE_ONLINE);
1851         if (device->state <= DASD_STATE_KNOWN) {
1852                 printk (KERN_WARNING
1853                         "dasd_generic discipline not found for %s\n",
1854                         cdev->dev.bus_id);
1855                 rc = -ENODEV;
1856                 dasd_set_target_state(device, DASD_STATE_NEW);
1857                 dasd_delete_device(device);
1858         } else
1859                 pr_debug("dasd_generic device %s found\n",
1860                                 cdev->dev.bus_id);
1861
1862         /* FIXME: we have to wait for the root device but we don't want
1863          * to wait for each single device but for all at once. */
1864         wait_event(dasd_init_waitq, _wait_for_device(device));
1865
1866         dasd_put_device(device);
1867
1868         return rc;
1869 }
1870
1871 int
1872 dasd_generic_set_offline (struct ccw_device *cdev)
1873 {
1874         struct dasd_device *device;
1875         int max_count;
1876
1877         device = dasd_device_from_cdev(cdev);
1878         if (IS_ERR(device))
1879                 return PTR_ERR(device);
1880         if (test_and_set_bit(DASD_FLAG_OFFLINE, &device->flags)) {
1881                 /* Already doing offline processing */
1882                 dasd_put_device(device);
1883                 return 0;
1884         }
1885         /*
1886          * We must make sure that this device is currently not in use.
1887          * The open_count is increased for every opener, that includes
1888          * the blkdev_get in dasd_scan_partitions. We are only interested
1889          * in the other openers.
1890          */
1891         max_count = device->bdev ? 0 : -1;
1892         if (atomic_read(&device->open_count) > max_count) {
1893                 printk (KERN_WARNING "Can't offline dasd device with open"
1894                         " count = %i.\n",
1895                         atomic_read(&device->open_count));
1896                 clear_bit(DASD_FLAG_OFFLINE, &device->flags);
1897                 dasd_put_device(device);
1898                 return -EBUSY;
1899         }
1900         dasd_set_target_state(device, DASD_STATE_NEW);
1901         /* dasd_delete_device destroys the device reference. */
1902         dasd_delete_device(device);
1903
1904         return 0;
1905 }
1906
1907 int
1908 dasd_generic_notify(struct ccw_device *cdev, int event)
1909 {
1910         struct dasd_device *device;
1911         struct dasd_ccw_req *cqr;
1912         unsigned long flags;
1913         int ret;
1914
1915         device = dasd_device_from_cdev(cdev);
1916         if (IS_ERR(device))
1917                 return 0;
1918         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1919         ret = 0;
1920         switch (event) {
1921         case CIO_GONE:
1922         case CIO_NO_PATH:
1923                 if (device->state < DASD_STATE_BASIC)
1924                         break;
1925                 /* Device is active. We want to keep it. */
1926                 if (test_bit(DASD_FLAG_DSC_ERROR, &device->flags)) {
1927                         list_for_each_entry(cqr, &device->ccw_queue, list)
1928                                 if (cqr->status == DASD_CQR_IN_IO)
1929                                         cqr->status = DASD_CQR_FAILED;
1930                         device->stopped |= DASD_STOPPED_DC_EIO;
1931                         dasd_schedule_bh(device);
1932                 } else {
1933                         list_for_each_entry(cqr, &device->ccw_queue, list)
1934                                 if (cqr->status == DASD_CQR_IN_IO) {
1935                                         cqr->status = DASD_CQR_QUEUED;
1936                                         cqr->retries++;
1937                                 }
1938                         device->stopped |= DASD_STOPPED_DC_WAIT;
1939                         dasd_set_timer(device, 0);
1940                 }
1941                 ret = 1;
1942                 break;
1943         case CIO_OPER:
1944                 /* FIXME: add a sanity check. */
1945                 device->stopped &= ~(DASD_STOPPED_DC_WAIT|DASD_STOPPED_DC_EIO);
1946                 dasd_schedule_bh(device);
1947                 ret = 1;
1948                 break;
1949         }
1950         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1951         dasd_put_device(device);
1952         return ret;
1953 }
1954
1955 /*
1956  * Automatically online either all dasd devices (dasd_autodetect) or
1957  * all devices specified with dasd= parameters.
1958  */
1959 static int
1960 __dasd_auto_online(struct device *dev, void *data)
1961 {
1962         struct ccw_device *cdev;
1963
1964         cdev = to_ccwdev(dev);
1965         if (dasd_autodetect || dasd_busid_known(cdev->dev.bus_id) == 0)
1966                 ccw_device_set_online(cdev);
1967         return 0;
1968 }
1969
1970 void
1971 dasd_generic_auto_online (struct ccw_driver *dasd_discipline_driver)
1972 {
1973         struct device_driver *drv;
1974
1975         drv = get_driver(&dasd_discipline_driver->driver);
1976         driver_for_each_device(drv, NULL, NULL, __dasd_auto_online);
1977         put_driver(drv);
1978 }
1979
1980 static int __init
1981 dasd_init(void)
1982 {
1983         int rc;
1984
1985         init_waitqueue_head(&dasd_init_waitq);
1986
1987         /* register 'common' DASD debug area, used for all DBF_XXX calls */
1988         dasd_debug_area = debug_register("dasd", 1, 2, 8 * sizeof (long));
1989         if (dasd_debug_area == NULL) {
1990                 rc = -ENOMEM;
1991                 goto failed;
1992         }
1993         debug_register_view(dasd_debug_area, &debug_sprintf_view);
1994         debug_set_level(dasd_debug_area, DBF_EMERG);
1995
1996         DBF_EVENT(DBF_EMERG, "%s", "debug area created");
1997
1998         dasd_diag_discipline_pointer = NULL;
1999
2000         rc = devfs_mk_dir("dasd");
2001         if (rc)
2002                 goto failed;
2003         rc = dasd_devmap_init();
2004         if (rc)
2005                 goto failed;
2006         rc = dasd_gendisk_init();
2007         if (rc)
2008                 goto failed;
2009         rc = dasd_parse();
2010         if (rc)
2011                 goto failed;
2012         rc = dasd_ioctl_init();
2013         if (rc)
2014                 goto failed;
2015 #ifdef CONFIG_PROC_FS
2016         rc = dasd_proc_init();
2017         if (rc)
2018                 goto failed;
2019 #endif
2020
2021         return 0;
2022 failed:
2023         MESSAGE(KERN_INFO, "%s", "initialization not performed due to errors");
2024         dasd_exit();
2025         return rc;
2026 }
2027
2028 module_init(dasd_init);
2029 module_exit(dasd_exit);
2030
2031 EXPORT_SYMBOL(dasd_debug_area);
2032 EXPORT_SYMBOL(dasd_diag_discipline_pointer);
2033
2034 EXPORT_SYMBOL(dasd_add_request_head);
2035 EXPORT_SYMBOL(dasd_add_request_tail);
2036 EXPORT_SYMBOL(dasd_cancel_req);
2037 EXPORT_SYMBOL(dasd_clear_timer);
2038 EXPORT_SYMBOL(dasd_enable_device);
2039 EXPORT_SYMBOL(dasd_int_handler);
2040 EXPORT_SYMBOL(dasd_kfree_request);
2041 EXPORT_SYMBOL(dasd_kick_device);
2042 EXPORT_SYMBOL(dasd_kmalloc_request);
2043 EXPORT_SYMBOL(dasd_schedule_bh);
2044 EXPORT_SYMBOL(dasd_set_target_state);
2045 EXPORT_SYMBOL(dasd_set_timer);
2046 EXPORT_SYMBOL(dasd_sfree_request);
2047 EXPORT_SYMBOL(dasd_sleep_on);
2048 EXPORT_SYMBOL(dasd_sleep_on_immediatly);
2049 EXPORT_SYMBOL(dasd_sleep_on_interruptible);
2050 EXPORT_SYMBOL(dasd_smalloc_request);
2051 EXPORT_SYMBOL(dasd_start_IO);
2052 EXPORT_SYMBOL(dasd_term_IO);
2053
2054 EXPORT_SYMBOL_GPL(dasd_generic_probe);
2055 EXPORT_SYMBOL_GPL(dasd_generic_remove);
2056 EXPORT_SYMBOL_GPL(dasd_generic_notify);
2057 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
2058 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
2059 EXPORT_SYMBOL_GPL(dasd_generic_auto_online);
2060
2061 /*
2062  * Overrides for Emacs so that we follow Linus's tabbing style.
2063  * Emacs will notice this stuff at the end of the file and automatically
2064  * adjust the settings for this buffer only.  This must remain at the end
2065  * of the file.
2066  * ---------------------------------------------------------------------------
2067  * Local variables:
2068  * c-indent-level: 4
2069  * c-brace-imaginary-offset: 0
2070  * c-brace-offset: -4
2071  * c-argdecl-indent: 4
2072  * c-label-offset: -4
2073  * c-continued-statement-offset: 4
2074  * c-continued-brace-offset: 0
2075  * indent-tabs-mode: 1
2076  * tab-width: 8
2077  * End:
2078  */