drivers/s390/cio/device_fsm.c

   1 /*
   2  * drivers/s390/cio/device_fsm.c
   3  * finite state machine for device handling
   4  *
   5  *    Copyright IBM Corp. 2002,2008
   6  *    Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/jiffies.h>
  13 #include <linux/string.h>
  14
  15 #include <asm/ccwdev.h>
  16 #include <asm/cio.h>
  17 #include <asm/chpid.h>
  18
  19 #include "cio.h"
  20 #include "cio_debug.h"
  21 #include "css.h"
  22 #include "device.h"
  23 #include "chsc.h"
  24 #include "ioasm.h"
  25 #include "chp.h"
  26
  27 static int timeout_log_enabled;
  28
  29 static int __init ccw_timeout_log_setup(char *unused)
  30 {
  31         timeout_log_enabled = 1;
  32         return 1;
  33 }
  34
  35 __setup("ccw_timeout_log", ccw_timeout_log_setup);
  36
  37 static void ccw_timeout_log(struct ccw_device *cdev)
  38 {
  39         struct schib schib;
  40         struct subchannel *sch;
  41         struct io_subchannel_private *private;
  42         union orb *orb;
  43         int cc;
  44
  45         sch = to_subchannel(cdev->dev.parent);
  46         private = to_io_private(sch);
  47         orb = &private->orb;
  48         cc = stsch_err(sch->schid, &schib);
  49
  50         printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
  51                "device information:\n", get_clock());
  52         printk(KERN_WARNING "cio: orb:\n");
  53         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  54                        orb, sizeof(*orb), 0);
  55         printk(KERN_WARNING "cio: ccw device bus id: %s\n",
  56                dev_name(&cdev->dev));
  57         printk(KERN_WARNING "cio: subchannel bus id: %s\n",
  58                dev_name(&sch->dev));
  59         printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
  60                "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
  61
  62         if (orb->tm.b) {
  63                 printk(KERN_WARNING "cio: orb indicates transport mode\n");
  64                 printk(KERN_WARNING "cio: last tcw:\n");
  65                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  66                                (void *)(addr_t)orb->tm.tcw,
  67                                sizeof(struct tcw), 0);
  68         } else {
  69                 printk(KERN_WARNING "cio: orb indicates command mode\n");
  70                 if ((void *)(addr_t)orb->cmd.cpa == &private->sense_ccw ||
  71                     (void *)(addr_t)orb->cmd.cpa == cdev->private->iccws)
  72                         printk(KERN_WARNING "cio: last channel program "
  73                                "(intern):\n");
  74                 else
  75                         printk(KERN_WARNING "cio: last channel program:\n");
  76
  77                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  78                                (void *)(addr_t)orb->cmd.cpa,
  79                                sizeof(struct ccw1), 0);
  80         }
  81         printk(KERN_WARNING "cio: ccw device state: %d\n",
  82                cdev->private->state);
  83         printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
  84         printk(KERN_WARNING "cio: schib:\n");
  85         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  86                        &schib, sizeof(schib), 0);
  87         printk(KERN_WARNING "cio: ccw device flags:\n");
  88         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  89                        &cdev->private->flags, sizeof(cdev->private->flags), 0);
  90 }
  91
  92 /*
  93  * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
  94  */
  95 static void
  96 ccw_device_timeout(unsigned long data)
  97 {
  98         struct ccw_device *cdev;
  99
 100         cdev = (struct ccw_device *) data;
 101         spin_lock_irq(cdev->ccwlock);
 102         if (timeout_log_enabled)
 103                 ccw_timeout_log(cdev);
 104         dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
 105         spin_unlock_irq(cdev->ccwlock);
 106 }
 107
 108 /*
 109  * Set timeout
 110  */
 111 void
 112 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
 113 {
 114         if (expires == 0) {
 115                 del_timer(&cdev->private->timer);
 116                 return;
 117         }
 118         if (timer_pending(&cdev->private->timer)) {
 119                 if (mod_timer(&cdev->private->timer, jiffies + expires))
 120                         return;
 121         }
 122         cdev->private->timer.function = ccw_device_timeout;
 123         cdev->private->timer.data = (unsigned long) cdev;
 124         cdev->private->timer.expires = jiffies + expires;
 125         add_timer(&cdev->private->timer);
 126 }
 127
 128 /*
 129  * Cancel running i/o. This is called repeatedly since halt/clear are
 130  * asynchronous operations. We do one try with cio_cancel, two tries
 131  * with cio_halt, 255 tries with cio_clear. If everythings fails panic.
 132  * Returns 0 if device now idle, -ENODEV for device not operational and
 133  * -EBUSY if an interrupt is expected (either from halt/clear or from a
 134  * status pending).
 135  */
 136 int
 137 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
 138 {
 139         struct subchannel *sch;
 140         int ret;
 141
 142         sch = to_subchannel(cdev->dev.parent);
 143         if (cio_update_schib(sch))
 144                 return -ENODEV;
 145         if (!sch->schib.pmcw.ena)
 146                 /* Not operational -> done. */
 147                 return 0;
 148         /* Stage 1: cancel io. */
 149         if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&
 150             !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
 151                 if (!scsw_is_tm(&sch->schib.scsw)) {
 152                         ret = cio_cancel(sch);
 153                         if (ret != -EINVAL)
 154                                 return ret;
 155                 }
 156                 /* cancel io unsuccessful or not applicable (transport mode).
 157                  * Continue with asynchronous instructions. */
 158                 cdev->private->iretry = 3;      /* 3 halt retries. */
 159         }
 160         if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
 161                 /* Stage 2: halt io. */
 162                 if (cdev->private->iretry) {
 163                         cdev->private->iretry--;
 164                         ret = cio_halt(sch);
 165                         if (ret != -EBUSY)
 166                                 return (ret == 0) ? -EBUSY : ret;
 167                 }
 168                 /* halt io unsuccessful. */
 169                 cdev->private->iretry = 255;    /* 255 clear retries. */
 170         }
 171         /* Stage 3: clear io. */
 172         if (cdev->private->iretry) {
 173                 cdev->private->iretry--;
 174                 ret = cio_clear (sch);
 175                 return (ret == 0) ? -EBUSY : ret;
 176         }
 177         panic("Can't stop i/o on subchannel.\n");
 178 }
 179
 180 void ccw_device_update_sense_data(struct ccw_device *cdev)
 181 {
 182         memset(&cdev->id, 0, sizeof(cdev->id));
 183         cdev->id.cu_type   = cdev->private->senseid.cu_type;
 184         cdev->id.cu_model  = cdev->private->senseid.cu_model;
 185         cdev->id.dev_type  = cdev->private->senseid.dev_type;
 186         cdev->id.dev_model = cdev->private->senseid.dev_model;
 187 }
 188
 189 int ccw_device_test_sense_data(struct ccw_device *cdev)
 190 {
 191         return cdev->id.cu_type == cdev->private->senseid.cu_type &&
 192                 cdev->id.cu_model == cdev->private->senseid.cu_model &&
 193                 cdev->id.dev_type == cdev->private->senseid.dev_type &&
 194                 cdev->id.dev_model == cdev->private->senseid.dev_model;
 195 }
 196
 197 /*
 198  * The machine won't give us any notification by machine check if a chpid has
 199  * been varied online on the SE so we have to find out by magic (i. e. driving
 200  * the channel subsystem to device selection and updating our path masks).
 201  */
 202 static void
 203 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
 204 {
 205         int mask, i;
 206         struct chp_id chpid;
 207
 208         chp_id_init(&chpid);
 209         for (i = 0; i<8; i++) {
 210                 mask = 0x80 >> i;
 211                 if (!(sch->lpm & mask))
 212                         continue;
 213                 if (old_lpm & mask)
 214                         continue;
 215                 chpid.id = sch->schib.pmcw.chpid[i];
 216                 if (!chp_is_registered(chpid))
 217                         css_schedule_eval_all();
 218         }
 219 }
 220
 221 /*
 222  * Stop device recognition.
 223  */
 224 static void
 225 ccw_device_recog_done(struct ccw_device *cdev, int state)
 226 {
 227         struct subchannel *sch;
 228         int old_lpm;
 229
 230         sch = to_subchannel(cdev->dev.parent);
 231
 232         if (cio_disable_subchannel(sch))
 233                 state = DEV_STATE_NOT_OPER;
 234         /*
 235          * Now that we tried recognition, we have performed device selection
 236          * through ssch() and the path information is up to date.
 237          */
 238         old_lpm = sch->lpm;
 239
 240         /* Check since device may again have become not operational. */
 241         if (cio_update_schib(sch))
 242                 state = DEV_STATE_NOT_OPER;
 243         else
 244                 sch->lpm = sch->schib.pmcw.pam & sch->opm;
 245
 246         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
 247                 /* Force reprobe on all chpids. */
 248                 old_lpm = 0;
 249         if (sch->lpm != old_lpm)
 250                 __recover_lost_chpids(sch, old_lpm);
 251         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
 252             (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
 253                 cdev->private->flags.recog_done = 1;
 254                 cdev->private->state = DEV_STATE_DISCONNECTED;
 255                 wake_up(&cdev->private->wait_q);
 256                 return;
 257         }
 258         if (cdev->private->flags.resuming) {
 259                 cdev->private->state = state;
 260                 cdev->private->flags.recog_done = 1;
 261                 wake_up(&cdev->private->wait_q);
 262                 return;
 263         }
 264         switch (state) {
 265         case DEV_STATE_NOT_OPER:
 266                 break;
 267         case DEV_STATE_OFFLINE:
 268                 if (!cdev->online) {
 269                         ccw_device_update_sense_data(cdev);
 270                         break;
 271                 }
 272                 cdev->private->state = DEV_STATE_OFFLINE;
 273                 cdev->private->flags.recog_done = 1;
 274                 if (ccw_device_test_sense_data(cdev)) {
 275                         cdev->private->flags.donotify = 1;
 276                         ccw_device_online(cdev);
 277                         wake_up(&cdev->private->wait_q);
 278                 } else {
 279                         ccw_device_update_sense_data(cdev);
 280                         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 281                 }
 282                 return;
 283         case DEV_STATE_BOXED:
 284                 if (cdev->id.cu_type != 0) { /* device was recognized before */
 285                         cdev->private->flags.recog_done = 1;
 286                         cdev->private->state = DEV_STATE_BOXED;
 287                         wake_up(&cdev->private->wait_q);
 288                         return;
 289                 }
 290                 break;
 291         }
 292         cdev->private->state = state;
 293         io_subchannel_recog_done(cdev);
 294         wake_up(&cdev->private->wait_q);
 295 }
 296
 297 /*
 298  * Function called from device_id.c after sense id has completed.
 299  */
 300 void
 301 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
 302 {
 303         switch (err) {
 304         case 0:
 305                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
 306                 break;
 307         case -ETIME:            /* Sense id stopped by timeout. */
 308                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
 309                 break;
 310         default:
 311                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 312                 break;
 313         }
 314 }
 315
 316 /**
 317   * ccw_device_notify() - inform the device's driver about an event
 318   * @cdev: device for which an event occured
 319   * @event: event that occurred
 320   *
 321   * Returns:
 322   *   -%EINVAL if the device is offline or has no driver.
 323   *   -%EOPNOTSUPP if the device's driver has no notifier registered.
 324   *   %NOTIFY_OK if the driver wants to keep the device.
 325   *   %NOTIFY_BAD if the driver doesn't want to keep the device.
 326   */
 327 int ccw_device_notify(struct ccw_device *cdev, int event)
 328 {
 329         int ret = -EINVAL;
 330
 331         if (!cdev->drv)
 332                 goto out;
 333         if (!cdev->online)
 334                 goto out;
 335         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
 336                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
 337                       event);
 338         if (!cdev->drv->notify) {
 339                 ret = -EOPNOTSUPP;
 340                 goto out;
 341         }
 342         if (cdev->drv->notify(cdev, event))
 343                 ret = NOTIFY_OK;
 344         else
 345                 ret = NOTIFY_BAD;
 346 out:
 347         return ret;
 348 }
 349
 350 static void ccw_device_oper_notify(struct ccw_device *cdev)
 351 {
 352         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 353
 354         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
 355                 /* Reenable channel measurements, if needed. */
 356                 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
 357                 /* Save indication for new paths. */
 358                 cdev->private->path_new_mask = sch->vpm;
 359                 return;
 360         }
 361         /* Driver doesn't want device back. */
 362         ccw_device_set_notoper(cdev);
 363         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 364 }
 365
 366 /*
 367  * Finished with online/offline processing.
 368  */
 369 static void
 370 ccw_device_done(struct ccw_device *cdev, int state)
 371 {
 372         struct subchannel *sch;
 373
 374         sch = to_subchannel(cdev->dev.parent);
 375
 376         ccw_device_set_timeout(cdev, 0);
 377
 378         if (state != DEV_STATE_ONLINE)
 379                 cio_disable_subchannel(sch);
 380
 381         /* Reset device status. */
 382         memset(&cdev->private->irb, 0, sizeof(struct irb));
 383
 384         cdev->private->state = state;
 385
 386         switch (state) {
 387         case DEV_STATE_BOXED:
 388                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
 389                               cdev->private->dev_id.devno, sch->schid.sch_no);
 390                 if (cdev->online &&
 391                     ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
 392                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 393                 cdev->private->flags.donotify = 0;
 394                 break;
 395         case DEV_STATE_NOT_OPER:
 396                 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
 397                               cdev->private->dev_id.devno, sch->schid.sch_no);
 398                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 399                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 400                 else
 401                         ccw_device_set_disconnected(cdev);
 402                 cdev->private->flags.donotify = 0;
 403                 break;
 404         case DEV_STATE_DISCONNECTED:
 405                 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
 406                               "%04x\n", cdev->private->dev_id.devno,
 407                               sch->schid.sch_no);
 408                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
 409                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 410                 else
 411                         ccw_device_set_disconnected(cdev);
 412                 cdev->private->flags.donotify = 0;
 413                 break;
 414         default:
 415                 break;
 416         }
 417
 418         if (cdev->private->flags.donotify) {
 419                 cdev->private->flags.donotify = 0;
 420                 ccw_device_oper_notify(cdev);
 421         }
 422         wake_up(&cdev->private->wait_q);
 423 }
 424
 425 /*
 426  * Start device recognition.
 427  */
 428 void ccw_device_recognition(struct ccw_device *cdev)
 429 {
 430         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 431
 432         /*
 433          * We used to start here with a sense pgid to find out whether a device
 434          * is locked by someone else. Unfortunately, the sense pgid command
 435          * code has other meanings on devices predating the path grouping
 436          * algorithm, so we start with sense id and box the device after an
 437          * timeout (or if sense pgid during path verification detects the device
 438          * is locked, as may happen on newer devices).
 439          */
 440         cdev->private->flags.recog_done = 0;
 441         cdev->private->state = DEV_STATE_SENSE_ID;
 442         if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
 443                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 444                 return;
 445         }
 446         ccw_device_sense_id_start(cdev);
 447 }
 448
 449 /*
 450  * Handle events for states that use the ccw request infrastructure.
 451  */
 452 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
 453 {
 454         switch (e) {
 455         case DEV_EVENT_NOTOPER:
 456                 ccw_request_notoper(cdev);
 457                 break;
 458         case DEV_EVENT_INTERRUPT:
 459                 ccw_request_handler(cdev);
 460                 break;
 461         case DEV_EVENT_TIMEOUT:
 462                 ccw_request_timeout(cdev);
 463                 break;
 464         default:
 465                 break;
 466         }
 467 }
 468
 469 static void ccw_device_report_path_events(struct ccw_device *cdev)
 470 {
 471         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 472         int path_event[8];
 473         int chp, mask;
 474
 475         for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
 476                 path_event[chp] = PE_NONE;
 477                 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
 478                         path_event[chp] |= PE_PATH_GONE;
 479                 if (mask & cdev->private->path_new_mask & sch->vpm)
 480                         path_event[chp] |= PE_PATH_AVAILABLE;
 481                 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
 482                         path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
 483         }
 484         if (cdev->online && cdev->drv->path_event)
 485                 cdev->drv->path_event(cdev, path_event);
 486 }
 487
 488 static void ccw_device_reset_path_events(struct ccw_device *cdev)
 489 {
 490         cdev->private->path_gone_mask = 0;
 491         cdev->private->path_new_mask = 0;
 492         cdev->private->pgid_reset_mask = 0;
 493 }
 494
 495 void
 496 ccw_device_verify_done(struct ccw_device *cdev, int err)
 497 {
 498         struct subchannel *sch;
 499
 500         sch = to_subchannel(cdev->dev.parent);
 501         /* Update schib - pom may have changed. */
 502         if (cio_update_schib(sch)) {
 503                 err = -ENODEV;
 504                 goto callback;
 505         }
 506         /* Update lpm with verified path mask. */
 507         sch->lpm = sch->vpm;
 508         /* Repeat path verification? */
 509         if (cdev->private->flags.doverify) {
 510                 ccw_device_verify_start(cdev);
 511                 return;
 512         }
 513 callback:
 514         switch (err) {
 515         case 0:
 516                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 517                 /* Deliver fake irb to device driver, if needed. */
 518                 if (cdev->private->flags.fake_irb) {
 519                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 520                         cdev->private->irb.scsw.cmd.cc = 1;
 521                         cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC;
 522                         cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND;
 523                         cdev->private->irb.scsw.cmd.stctl =
 524                                 SCSW_STCTL_STATUS_PEND;
 525                         cdev->private->flags.fake_irb = 0;
 526                         if (cdev->handler)
 527                                 cdev->handler(cdev, cdev->private->intparm,
 528                                               &cdev->private->irb);
 529                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 530                 }
 531                 ccw_device_report_path_events(cdev);
 532                 break;
 533         case -ETIME:
 534         case -EUSERS:
 535                 /* Reset oper notify indication after verify error. */
 536                 cdev->private->flags.donotify = 0;
 537                 ccw_device_done(cdev, DEV_STATE_BOXED);
 538                 break;
 539         case -EACCES:
 540                 /* Reset oper notify indication after verify error. */
 541                 cdev->private->flags.donotify = 0;
 542                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
 543                 break;
 544         default:
 545                 /* Reset oper notify indication after verify error. */
 546                 cdev->private->flags.donotify = 0;
 547                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 548                 break;
 549         }
 550         ccw_device_reset_path_events(cdev);
 551 }
 552
 553 /*
 554  * Get device online.
 555  */
 556 int
 557 ccw_device_online(struct ccw_device *cdev)
 558 {
 559         struct subchannel *sch;
 560         int ret;
 561
 562         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 563             (cdev->private->state != DEV_STATE_BOXED))
 564                 return -EINVAL;
 565         sch = to_subchannel(cdev->dev.parent);
 566         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
 567         if (ret != 0) {
 568                 /* Couldn't enable the subchannel for i/o. Sick device. */
 569                 if (ret == -ENODEV)
 570                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 571                 return ret;
 572         }
 573         /* Start initial path verification. */
 574         cdev->private->state = DEV_STATE_VERIFY;
 575         ccw_device_verify_start(cdev);
 576         return 0;
 577 }
 578
 579 void
 580 ccw_device_disband_done(struct ccw_device *cdev, int err)
 581 {
 582         switch (err) {
 583         case 0:
 584                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 585                 break;
 586         case -ETIME:
 587                 ccw_device_done(cdev, DEV_STATE_BOXED);
 588                 break;
 589         default:
 590                 cdev->private->flags.donotify = 0;
 591                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 592                 break;
 593         }
 594 }
 595
 596 /*
 597  * Shutdown device.
 598  */
 599 int
 600 ccw_device_offline(struct ccw_device *cdev)
 601 {
 602         struct subchannel *sch;
 603
 604         /* Allow ccw_device_offline while disconnected. */
 605         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
 606             cdev->private->state == DEV_STATE_NOT_OPER) {
 607                 cdev->private->flags.donotify = 0;
 608                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 609                 return 0;
 610         }
 611         if (cdev->private->state == DEV_STATE_BOXED) {
 612                 ccw_device_done(cdev, DEV_STATE_BOXED);
 613                 return 0;
 614         }
 615         if (ccw_device_is_orphan(cdev)) {
 616                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 617                 return 0;
 618         }
 619         sch = to_subchannel(cdev->dev.parent);
 620         if (cio_update_schib(sch))
 621                 return -ENODEV;
 622         if (scsw_actl(&sch->schib.scsw) != 0)
 623                 return -EBUSY;
 624         if (cdev->private->state != DEV_STATE_ONLINE)
 625                 return -EINVAL;
 626         /* Are we doing path grouping? */
 627         if (!cdev->private->flags.pgroup) {
 628                 /* No, set state offline immediately. */
 629                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 630                 return 0;
 631         }
 632         /* Start Set Path Group commands. */
 633         cdev->private->state = DEV_STATE_DISBAND_PGID;
 634         ccw_device_disband_start(cdev);
 635         return 0;
 636 }
 637
 638 /*
 639  * Handle not operational event in non-special state.
 640  */
 641 static void ccw_device_generic_notoper(struct ccw_device *cdev,
 642                                        enum dev_event dev_event)
 643 {
 644         if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 645                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 646         else
 647                 ccw_device_set_disconnected(cdev);
 648 }
 649
 650 /*
 651  * Handle path verification event in offline state.
 652  */
 653 static void ccw_device_offline_verify(struct ccw_device *cdev,
 654                                       enum dev_event dev_event)
 655 {
 656         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 657
 658         css_schedule_eval(sch->schid);
 659 }
 660
 661 /*
 662  * Handle path verification event.
 663  */
 664 static void
 665 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 666 {
 667         struct subchannel *sch;
 668
 669         if (cdev->private->state == DEV_STATE_W4SENSE) {
 670                 cdev->private->flags.doverify = 1;
 671                 return;
 672         }
 673         sch = to_subchannel(cdev->dev.parent);
 674         /*
 675          * Since we might not just be coming from an interrupt from the
 676          * subchannel we have to update the schib.
 677          */
 678         if (cio_update_schib(sch)) {
 679                 ccw_device_verify_done(cdev, -ENODEV);
 680                 return;
 681         }
 682
 683         if (scsw_actl(&sch->schib.scsw) != 0 ||
 684             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
 685             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
 686                 /*
 687                  * No final status yet or final status not yet delivered
 688                  * to the device driver. Can't do path verfication now,
 689                  * delay until final status was delivered.
 690                  */
 691                 cdev->private->flags.doverify = 1;
 692                 return;
 693         }
 694         /* Device is idle, we can do the path verification. */
 695         cdev->private->state = DEV_STATE_VERIFY;
 696         ccw_device_verify_start(cdev);
 697 }
 698
 699 /*
 700  * Handle path verification event in boxed state.
 701  */
 702 static void ccw_device_boxed_verify(struct ccw_device *cdev,
 703                                     enum dev_event dev_event)
 704 {
 705         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 706
 707         if (cdev->online) {
 708                 if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
 709                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 710                 else
 711                         ccw_device_online_verify(cdev, dev_event);
 712         } else
 713                 css_schedule_eval(sch->schid);
 714 }
 715
 716 /*
 717  * Got an interrupt for a normal io (state online).
 718  */
 719 static void
 720 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 721 {
 722         struct irb *irb;
 723         int is_cmd;
 724
 725         irb = (struct irb *)&S390_lowcore.irb;
 726         is_cmd = !scsw_is_tm(&irb->scsw);
 727         /* Check for unsolicited interrupt. */
 728         if (!scsw_is_solicited(&irb->scsw)) {
 729                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
 730                     !irb->esw.esw0.erw.cons) {
 731                         /* Unit check but no sense data. Need basic sense. */
 732                         if (ccw_device_do_sense(cdev, irb) != 0)
 733                                 goto call_handler_unsol;
 734                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
 735                         cdev->private->state = DEV_STATE_W4SENSE;
 736                         cdev->private->intparm = 0;
 737                         return;
 738                 }
 739 call_handler_unsol:
 740                 if (cdev->handler)
 741                         cdev->handler (cdev, 0, irb);
 742                 if (cdev->private->flags.doverify)
 743                         ccw_device_online_verify(cdev, 0);
 744                 return;
 745         }
 746         /* Accumulate status and find out if a basic sense is needed. */
 747         ccw_device_accumulate_irb(cdev, irb);
 748         if (is_cmd && cdev->private->flags.dosense) {
 749                 if (ccw_device_do_sense(cdev, irb) == 0) {
 750                         cdev->private->state = DEV_STATE_W4SENSE;
 751                 }
 752                 return;
 753         }
 754         /* Call the handler. */
 755         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 756                 /* Start delayed path verification. */
 757                 ccw_device_online_verify(cdev, 0);
 758 }
 759
 760 /*
 761  * Got an timeout in online state.
 762  */
 763 static void
 764 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 765 {
 766         int ret;
 767
 768         ccw_device_set_timeout(cdev, 0);
 769         ret = ccw_device_cancel_halt_clear(cdev);
 770         if (ret == -EBUSY) {
 771                 ccw_device_set_timeout(cdev, 3*HZ);
 772                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 773                 return;
 774         }
 775         if (ret == -ENODEV)
 776                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 777         else if (cdev->handler)
 778                 cdev->handler(cdev, cdev->private->intparm,
 779                               ERR_PTR(-ETIMEDOUT));
 780 }
 781
 782 /*
 783  * Got an interrupt for a basic sense.
 784  */
 785 static void
 786 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 787 {
 788         struct irb *irb;
 789
 790         irb = (struct irb *)&S390_lowcore.irb;
 791         /* Check for unsolicited interrupt. */
 792         if (scsw_stctl(&irb->scsw) ==
 793             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 794                 if (scsw_cc(&irb->scsw) == 1)
 795                         /* Basic sense hasn't started. Try again. */
 796                         ccw_device_do_sense(cdev, irb);
 797                 else {
 798                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
 799                                       "interrupt during w4sense...\n",
 800                                       cdev->private->dev_id.ssid,
 801                                       cdev->private->dev_id.devno);
 802                         if (cdev->handler)
 803                                 cdev->handler (cdev, 0, irb);
 804                 }
 805                 return;
 806         }
 807         /*
 808          * Check if a halt or clear has been issued in the meanwhile. If yes,
 809          * only deliver the halt/clear interrupt to the device driver as if it
 810          * had killed the original request.
 811          */
 812         if (scsw_fctl(&irb->scsw) &
 813             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
 814                 cdev->private->flags.dosense = 0;
 815                 memset(&cdev->private->irb, 0, sizeof(struct irb));
 816                 ccw_device_accumulate_irb(cdev, irb);
 817                 goto call_handler;
 818         }
 819         /* Add basic sense info to irb. */
 820         ccw_device_accumulate_basic_sense(cdev, irb);
 821         if (cdev->private->flags.dosense) {
 822                 /* Another basic sense is needed. */
 823                 ccw_device_do_sense(cdev, irb);
 824                 return;
 825         }
 826 call_handler:
 827         cdev->private->state = DEV_STATE_ONLINE;
 828         /* In case sensing interfered with setting the device online */
 829         wake_up(&cdev->private->wait_q);
 830         /* Call the handler. */
 831         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 832                 /* Start delayed path verification. */
 833                 ccw_device_online_verify(cdev, 0);
 834 }
 835
 836 static void
 837 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 838 {
 839         struct subchannel *sch;
 840
 841         sch = to_subchannel(cdev->dev.parent);
 842         ccw_device_set_timeout(cdev, 0);
 843         /* Start delayed path verification. */
 844         ccw_device_online_verify(cdev, 0);
 845         /* OK, i/o is dead now. Call interrupt handler. */
 846         if (cdev->handler)
 847                 cdev->handler(cdev, cdev->private->intparm,
 848                               ERR_PTR(-EIO));
 849 }
 850
 851 static void
 852 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 853 {
 854         int ret;
 855
 856         ret = ccw_device_cancel_halt_clear(cdev);
 857         if (ret == -EBUSY) {
 858                 ccw_device_set_timeout(cdev, 3*HZ);
 859                 return;
 860         }
 861         /* Start delayed path verification. */
 862         ccw_device_online_verify(cdev, 0);
 863         if (cdev->handler)
 864                 cdev->handler(cdev, cdev->private->intparm,
 865                               ERR_PTR(-EIO));
 866 }
 867
 868 void ccw_device_kill_io(struct ccw_device *cdev)
 869 {
 870         int ret;
 871
 872         ret = ccw_device_cancel_halt_clear(cdev);
 873         if (ret == -EBUSY) {
 874                 ccw_device_set_timeout(cdev, 3*HZ);
 875                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 876                 return;
 877         }
 878         /* Start delayed path verification. */
 879         ccw_device_online_verify(cdev, 0);
 880         if (cdev->handler)
 881                 cdev->handler(cdev, cdev->private->intparm,
 882                               ERR_PTR(-EIO));
 883 }
 884
 885 static void
 886 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 887 {
 888         /* Start verification after current task finished. */
 889         cdev->private->flags.doverify = 1;
 890 }
 891
 892 static void
 893 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 894 {
 895         struct subchannel *sch;
 896
 897         sch = to_subchannel(cdev->dev.parent);
 898         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
 899                 /* Couldn't enable the subchannel for i/o. Sick device. */
 900                 return;
 901         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 902         ccw_device_sense_id_start(cdev);
 903 }
 904
 905 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
 906 {
 907         struct subchannel *sch;
 908
 909         if (cdev->private->state != DEV_STATE_DISCONNECTED)
 910                 return;
 911
 912         sch = to_subchannel(cdev->dev.parent);
 913         /* Update some values. */
 914         if (cio_update_schib(sch))
 915                 return;
 916         /*
 917          * The pim, pam, pom values may not be accurate, but they are the best
 918          * we have before performing device selection :/
 919          */
 920         sch->lpm = sch->schib.pmcw.pam & sch->opm;
 921         /*
 922          * Use the initial configuration since we can't be shure that the old
 923          * paths are valid.
 924          */
 925         io_subchannel_init_config(sch);
 926         if (cio_commit_config(sch))
 927                 return;
 928
 929         /* We should also udate ssd info, but this has to wait. */
 930         /* Check if this is another device which appeared on the same sch. */
 931         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
 932                 css_schedule_eval(sch->schid);
 933         else
 934                 ccw_device_start_id(cdev, 0);
 935 }
 936
 937 static void ccw_device_disabled_irq(struct ccw_device *cdev,
 938                                     enum dev_event dev_event)
 939 {
 940         struct subchannel *sch;
 941
 942         sch = to_subchannel(cdev->dev.parent);
 943         /*
 944          * An interrupt in a disabled state means a previous disable was not
 945          * successful - should not happen, but we try to disable again.
 946          */
 947         cio_disable_subchannel(sch);
 948 }
 949
 950 static void
 951 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
 952 {
 953         retry_set_schib(cdev);
 954         cdev->private->state = DEV_STATE_ONLINE;
 955         dev_fsm_event(cdev, dev_event);
 956 }
 957
 958 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
 959                                        enum dev_event dev_event)
 960 {
 961         cmf_retry_copy_block(cdev);
 962         cdev->private->state = DEV_STATE_ONLINE;
 963         dev_fsm_event(cdev, dev_event);
 964 }
 965
 966 static void
 967 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
 968 {
 969         ccw_device_set_timeout(cdev, 0);
 970         cdev->private->state = DEV_STATE_NOT_OPER;
 971         wake_up(&cdev->private->wait_q);
 972 }
 973
 974 static void
 975 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 976 {
 977         int ret;
 978
 979         ret = ccw_device_cancel_halt_clear(cdev);
 980         if (ret == -EBUSY) {
 981                 ccw_device_set_timeout(cdev, HZ/10);
 982         } else {
 983                 cdev->private->state = DEV_STATE_NOT_OPER;
 984                 wake_up(&cdev->private->wait_q);
 985         }
 986 }
 987
 988 /*
 989  * No operation action. This is used e.g. to ignore a timeout event in
 990  * state offline.
 991  */
 992 static void
 993 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
 994 {
 995 }
 996
 997 /*
 998  * device statemachine
 999  */
1000 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1001         [DEV_STATE_NOT_OPER] = {
1002                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1003                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1004                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1005                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1006         },
1007         [DEV_STATE_SENSE_PGID] = {
1008                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1009                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1010                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1011                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1012         },
1013         [DEV_STATE_SENSE_ID] = {
1014                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1015                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1016                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1017                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1018         },
1019         [DEV_STATE_OFFLINE] = {
1020                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1021                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1022                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1023                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
1024         },
1025         [DEV_STATE_VERIFY] = {
1026                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1027                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1028                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1029                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
1030         },
1031         [DEV_STATE_ONLINE] = {
1032                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1033                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1034                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1035                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1036         },
1037         [DEV_STATE_W4SENSE] = {
1038                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1039                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1040                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1041                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1042         },
1043         [DEV_STATE_DISBAND_PGID] = {
1044                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1045                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1046                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1047                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1048         },
1049         [DEV_STATE_BOXED] = {
1050                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1051                 [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
1052                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1053                 [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
1054         },
1055         /* states to wait for i/o completion before doing something */
1056         [DEV_STATE_TIMEOUT_KILL] = {
1057                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1058                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1059                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1060                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1061         },
1062         [DEV_STATE_QUIESCE] = {
1063                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1064                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1065                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1066                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1067         },
1068         /* special states for devices gone not operational */
1069         [DEV_STATE_DISCONNECTED] = {
1070                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1071                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1072                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1073                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1074         },
1075         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1076                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1077                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1078                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1079                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1080         },
1081         [DEV_STATE_CMFCHANGE] = {
1082                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1083                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1084                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1085                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1086         },
1087         [DEV_STATE_CMFUPDATE] = {
1088                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1089                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1090                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1091                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1092         },
1093         [DEV_STATE_STEAL_LOCK] = {
1094                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1095                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1096                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1097                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1098         },
1099 };
1100
1101 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);