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 ([email protected])
   7  *               Martin Schwidefsky ([email protected])
   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         /* Function was unsuccessful */
 178         CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
 179                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno);
 180         return -EIO;
 181 }
 182
 183 void ccw_device_update_sense_data(struct ccw_device *cdev)
 184 {
 185         memset(&cdev->id, 0, sizeof(cdev->id));
 186         cdev->id.cu_type   = cdev->private->senseid.cu_type;
 187         cdev->id.cu_model  = cdev->private->senseid.cu_model;
 188         cdev->id.dev_type  = cdev->private->senseid.dev_type;
 189         cdev->id.dev_model = cdev->private->senseid.dev_model;
 190 }
 191
 192 int ccw_device_test_sense_data(struct ccw_device *cdev)
 193 {
 194         return cdev->id.cu_type == cdev->private->senseid.cu_type &&
 195                 cdev->id.cu_model == cdev->private->senseid.cu_model &&
 196                 cdev->id.dev_type == cdev->private->senseid.dev_type &&
 197                 cdev->id.dev_model == cdev->private->senseid.dev_model;
 198 }
 199
 200 /*
 201  * The machine won't give us any notification by machine check if a chpid has
 202  * been varied online on the SE so we have to find out by magic (i. e. driving
 203  * the channel subsystem to device selection and updating our path masks).
 204  */
 205 static void
 206 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
 207 {
 208         int mask, i;
 209         struct chp_id chpid;
 210
 211         chp_id_init(&chpid);
 212         for (i = 0; i<8; i++) {
 213                 mask = 0x80 >> i;
 214                 if (!(sch->lpm & mask))
 215                         continue;
 216                 if (old_lpm & mask)
 217                         continue;
 218                 chpid.id = sch->schib.pmcw.chpid[i];
 219                 if (!chp_is_registered(chpid))
 220                         css_schedule_eval_all();
 221         }
 222 }
 223
 224 /*
 225  * Stop device recognition.
 226  */
 227 static void
 228 ccw_device_recog_done(struct ccw_device *cdev, int state)
 229 {
 230         struct subchannel *sch;
 231         int old_lpm;
 232
 233         sch = to_subchannel(cdev->dev.parent);
 234
 235         if (cio_disable_subchannel(sch))
 236                 state = DEV_STATE_NOT_OPER;
 237         /*
 238          * Now that we tried recognition, we have performed device selection
 239          * through ssch() and the path information is up to date.
 240          */
 241         old_lpm = sch->lpm;
 242
 243         /* Check since device may again have become not operational. */
 244         if (cio_update_schib(sch))
 245                 state = DEV_STATE_NOT_OPER;
 246         else
 247                 sch->lpm = sch->schib.pmcw.pam & sch->opm;
 248
 249         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
 250                 /* Force reprobe on all chpids. */
 251                 old_lpm = 0;
 252         if (sch->lpm != old_lpm)
 253                 __recover_lost_chpids(sch, old_lpm);
 254         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
 255             (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
 256                 cdev->private->flags.recog_done = 1;
 257                 cdev->private->state = DEV_STATE_DISCONNECTED;
 258                 wake_up(&cdev->private->wait_q);
 259                 return;
 260         }
 261         if (cdev->private->flags.resuming) {
 262                 cdev->private->state = state;
 263                 cdev->private->flags.recog_done = 1;
 264                 wake_up(&cdev->private->wait_q);
 265                 return;
 266         }
 267         switch (state) {
 268         case DEV_STATE_NOT_OPER:
 269                 break;
 270         case DEV_STATE_OFFLINE:
 271                 if (!cdev->online) {
 272                         ccw_device_update_sense_data(cdev);
 273                         break;
 274                 }
 275                 cdev->private->state = DEV_STATE_OFFLINE;
 276                 cdev->private->flags.recog_done = 1;
 277                 if (ccw_device_test_sense_data(cdev)) {
 278                         cdev->private->flags.donotify = 1;
 279                         ccw_device_online(cdev);
 280                         wake_up(&cdev->private->wait_q);
 281                 } else {
 282                         ccw_device_update_sense_data(cdev);
 283                         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 284                 }
 285                 return;
 286         case DEV_STATE_BOXED:
 287                 if (cdev->id.cu_type != 0) { /* device was recognized before */
 288                         cdev->private->flags.recog_done = 1;
 289                         cdev->private->state = DEV_STATE_BOXED;
 290                         wake_up(&cdev->private->wait_q);
 291                         return;
 292                 }
 293                 break;
 294         }
 295         cdev->private->state = state;
 296         io_subchannel_recog_done(cdev);
 297         wake_up(&cdev->private->wait_q);
 298 }
 299
 300 /*
 301  * Function called from device_id.c after sense id has completed.
 302  */
 303 void
 304 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
 305 {
 306         switch (err) {
 307         case 0:
 308                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
 309                 break;
 310         case -ETIME:            /* Sense id stopped by timeout. */
 311                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
 312                 break;
 313         default:
 314                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 315                 break;
 316         }
 317 }
 318
 319 /**
 320   * ccw_device_notify() - inform the device's driver about an event
 321   * @cdev: device for which an event occurred
 322   * @event: event that occurred
 323   *
 324   * Returns:
 325   *   -%EINVAL if the device is offline or has no driver.
 326   *   -%EOPNOTSUPP if the device's driver has no notifier registered.
 327   *   %NOTIFY_OK if the driver wants to keep the device.
 328   *   %NOTIFY_BAD if the driver doesn't want to keep the device.
 329   */
 330 int ccw_device_notify(struct ccw_device *cdev, int event)
 331 {
 332         int ret = -EINVAL;
 333
 334         if (!cdev->drv)
 335                 goto out;
 336         if (!cdev->online)
 337                 goto out;
 338         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
 339                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
 340                       event);
 341         if (!cdev->drv->notify) {
 342                 ret = -EOPNOTSUPP;
 343                 goto out;
 344         }
 345         if (cdev->drv->notify(cdev, event))
 346                 ret = NOTIFY_OK;
 347         else
 348                 ret = NOTIFY_BAD;
 349 out:
 350         return ret;
 351 }
 352
 353 static void ccw_device_oper_notify(struct ccw_device *cdev)
 354 {
 355         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 356
 357         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
 358                 /* Reenable channel measurements, if needed. */
 359                 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
 360                 /* Save indication for new paths. */
 361                 cdev->private->path_new_mask = sch->vpm;
 362                 return;
 363         }
 364         /* Driver doesn't want device back. */
 365         ccw_device_set_notoper(cdev);
 366         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 367 }
 368
 369 /*
 370  * Finished with online/offline processing.
 371  */
 372 static void
 373 ccw_device_done(struct ccw_device *cdev, int state)
 374 {
 375         struct subchannel *sch;
 376
 377         sch = to_subchannel(cdev->dev.parent);
 378
 379         ccw_device_set_timeout(cdev, 0);
 380
 381         if (state != DEV_STATE_ONLINE)
 382                 cio_disable_subchannel(sch);
 383
 384         /* Reset device status. */
 385         memset(&cdev->private->irb, 0, sizeof(struct irb));
 386
 387         cdev->private->state = state;
 388
 389         switch (state) {
 390         case DEV_STATE_BOXED:
 391                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
 392                               cdev->private->dev_id.devno, sch->schid.sch_no);
 393                 if (cdev->online &&
 394                     ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
 395                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 396                 cdev->private->flags.donotify = 0;
 397                 break;
 398         case DEV_STATE_NOT_OPER:
 399                 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
 400                               cdev->private->dev_id.devno, sch->schid.sch_no);
 401                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 402                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 403                 else
 404                         ccw_device_set_disconnected(cdev);
 405                 cdev->private->flags.donotify = 0;
 406                 break;
 407         case DEV_STATE_DISCONNECTED:
 408                 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
 409                               "%04x\n", cdev->private->dev_id.devno,
 410                               sch->schid.sch_no);
 411                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
 412                         cdev->private->state = DEV_STATE_NOT_OPER;
 413                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 414                 } else
 415                         ccw_device_set_disconnected(cdev);
 416                 cdev->private->flags.donotify = 0;
 417                 break;
 418         default:
 419                 break;
 420         }
 421
 422         if (cdev->private->flags.donotify) {
 423                 cdev->private->flags.donotify = 0;
 424                 ccw_device_oper_notify(cdev);
 425         }
 426         wake_up(&cdev->private->wait_q);
 427 }
 428
 429 /*
 430  * Start device recognition.
 431  */
 432 void ccw_device_recognition(struct ccw_device *cdev)
 433 {
 434         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 435
 436         /*
 437          * We used to start here with a sense pgid to find out whether a device
 438          * is locked by someone else. Unfortunately, the sense pgid command
 439          * code has other meanings on devices predating the path grouping
 440          * algorithm, so we start with sense id and box the device after an
 441          * timeout (or if sense pgid during path verification detects the device
 442          * is locked, as may happen on newer devices).
 443          */
 444         cdev->private->flags.recog_done = 0;
 445         cdev->private->state = DEV_STATE_SENSE_ID;
 446         if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
 447                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 448                 return;
 449         }
 450         ccw_device_sense_id_start(cdev);
 451 }
 452
 453 /*
 454  * Handle events for states that use the ccw request infrastructure.
 455  */
 456 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
 457 {
 458         switch (e) {
 459         case DEV_EVENT_NOTOPER:
 460                 ccw_request_notoper(cdev);
 461                 break;
 462         case DEV_EVENT_INTERRUPT:
 463                 ccw_request_handler(cdev);
 464                 break;
 465         case DEV_EVENT_TIMEOUT:
 466                 ccw_request_timeout(cdev);
 467                 break;
 468         default:
 469                 break;
 470         }
 471 }
 472
 473 static void ccw_device_report_path_events(struct ccw_device *cdev)
 474 {
 475         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 476         int path_event[8];
 477         int chp, mask;
 478
 479         for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
 480                 path_event[chp] = PE_NONE;
 481                 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
 482                         path_event[chp] |= PE_PATH_GONE;
 483                 if (mask & cdev->private->path_new_mask & sch->vpm)
 484                         path_event[chp] |= PE_PATH_AVAILABLE;
 485                 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
 486                         path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
 487         }
 488         if (cdev->online && cdev->drv->path_event)
 489                 cdev->drv->path_event(cdev, path_event);
 490 }
 491
 492 static void ccw_device_reset_path_events(struct ccw_device *cdev)
 493 {
 494         cdev->private->path_gone_mask = 0;
 495         cdev->private->path_new_mask = 0;
 496         cdev->private->pgid_reset_mask = 0;
 497 }
 498
 499 void
 500 ccw_device_verify_done(struct ccw_device *cdev, int err)
 501 {
 502         struct subchannel *sch;
 503
 504         sch = to_subchannel(cdev->dev.parent);
 505         /* Update schib - pom may have changed. */
 506         if (cio_update_schib(sch)) {
 507                 err = -ENODEV;
 508                 goto callback;
 509         }
 510         /* Update lpm with verified path mask. */
 511         sch->lpm = sch->vpm;
 512         /* Repeat path verification? */
 513         if (cdev->private->flags.doverify) {
 514                 ccw_device_verify_start(cdev);
 515                 return;
 516         }
 517 callback:
 518         switch (err) {
 519         case 0:
 520                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 521                 /* Deliver fake irb to device driver, if needed. */
 522                 if (cdev->private->flags.fake_irb) {
 523                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 524                         cdev->private->irb.scsw.cmd.cc = 1;
 525                         cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC;
 526                         cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND;
 527                         cdev->private->irb.scsw.cmd.stctl =
 528                                 SCSW_STCTL_STATUS_PEND;
 529                         cdev->private->flags.fake_irb = 0;
 530                         if (cdev->handler)
 531                                 cdev->handler(cdev, cdev->private->intparm,
 532                                               &cdev->private->irb);
 533                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 534                 }
 535                 ccw_device_report_path_events(cdev);
 536                 break;
 537         case -ETIME:
 538         case -EUSERS:
 539                 /* Reset oper notify indication after verify error. */
 540                 cdev->private->flags.donotify = 0;
 541                 ccw_device_done(cdev, DEV_STATE_BOXED);
 542                 break;
 543         case -EACCES:
 544                 /* Reset oper notify indication after verify error. */
 545                 cdev->private->flags.donotify = 0;
 546                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
 547                 break;
 548         default:
 549                 /* Reset oper notify indication after verify error. */
 550                 cdev->private->flags.donotify = 0;
 551                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 552                 break;
 553         }
 554         ccw_device_reset_path_events(cdev);
 555 }
 556
 557 /*
 558  * Get device online.
 559  */
 560 int
 561 ccw_device_online(struct ccw_device *cdev)
 562 {
 563         struct subchannel *sch;
 564         int ret;
 565
 566         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 567             (cdev->private->state != DEV_STATE_BOXED))
 568                 return -EINVAL;
 569         sch = to_subchannel(cdev->dev.parent);
 570         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
 571         if (ret != 0) {
 572                 /* Couldn't enable the subchannel for i/o. Sick device. */
 573                 if (ret == -ENODEV)
 574                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 575                 return ret;
 576         }
 577         /* Start initial path verification. */
 578         cdev->private->state = DEV_STATE_VERIFY;
 579         ccw_device_verify_start(cdev);
 580         return 0;
 581 }
 582
 583 void
 584 ccw_device_disband_done(struct ccw_device *cdev, int err)
 585 {
 586         switch (err) {
 587         case 0:
 588                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 589                 break;
 590         case -ETIME:
 591                 ccw_device_done(cdev, DEV_STATE_BOXED);
 592                 break;
 593         default:
 594                 cdev->private->flags.donotify = 0;
 595                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 596                 break;
 597         }
 598 }
 599
 600 /*
 601  * Shutdown device.
 602  */
 603 int
 604 ccw_device_offline(struct ccw_device *cdev)
 605 {
 606         struct subchannel *sch;
 607
 608         /* Allow ccw_device_offline while disconnected. */
 609         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
 610             cdev->private->state == DEV_STATE_NOT_OPER) {
 611                 cdev->private->flags.donotify = 0;
 612                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 613                 return 0;
 614         }
 615         if (cdev->private->state == DEV_STATE_BOXED) {
 616                 ccw_device_done(cdev, DEV_STATE_BOXED);
 617                 return 0;
 618         }
 619         if (ccw_device_is_orphan(cdev)) {
 620                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 621                 return 0;
 622         }
 623         sch = to_subchannel(cdev->dev.parent);
 624         if (cio_update_schib(sch))
 625                 return -ENODEV;
 626         if (scsw_actl(&sch->schib.scsw) != 0)
 627                 return -EBUSY;
 628         if (cdev->private->state != DEV_STATE_ONLINE)
 629                 return -EINVAL;
 630         /* Are we doing path grouping? */
 631         if (!cdev->private->flags.pgroup) {
 632                 /* No, set state offline immediately. */
 633                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 634                 return 0;
 635         }
 636         /* Start Set Path Group commands. */
 637         cdev->private->state = DEV_STATE_DISBAND_PGID;
 638         ccw_device_disband_start(cdev);
 639         return 0;
 640 }
 641
 642 /*
 643  * Handle not operational event in non-special state.
 644  */
 645 static void ccw_device_generic_notoper(struct ccw_device *cdev,
 646                                        enum dev_event dev_event)
 647 {
 648         if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 649                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 650         else
 651                 ccw_device_set_disconnected(cdev);
 652 }
 653
 654 /*
 655  * Handle path verification event in offline state.
 656  */
 657 static void ccw_device_offline_verify(struct ccw_device *cdev,
 658                                       enum dev_event dev_event)
 659 {
 660         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 661
 662         css_schedule_eval(sch->schid);
 663 }
 664
 665 /*
 666  * Handle path verification event.
 667  */
 668 static void
 669 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 670 {
 671         struct subchannel *sch;
 672
 673         if (cdev->private->state == DEV_STATE_W4SENSE) {
 674                 cdev->private->flags.doverify = 1;
 675                 return;
 676         }
 677         sch = to_subchannel(cdev->dev.parent);
 678         /*
 679          * Since we might not just be coming from an interrupt from the
 680          * subchannel we have to update the schib.
 681          */
 682         if (cio_update_schib(sch)) {
 683                 ccw_device_verify_done(cdev, -ENODEV);
 684                 return;
 685         }
 686
 687         if (scsw_actl(&sch->schib.scsw) != 0 ||
 688             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
 689             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
 690                 /*
 691                  * No final status yet or final status not yet delivered
 692                  * to the device driver. Can't do path verification now,
 693                  * delay until final status was delivered.
 694                  */
 695                 cdev->private->flags.doverify = 1;
 696                 return;
 697         }
 698         /* Device is idle, we can do the path verification. */
 699         cdev->private->state = DEV_STATE_VERIFY;
 700         ccw_device_verify_start(cdev);
 701 }
 702
 703 /*
 704  * Handle path verification event in boxed state.
 705  */
 706 static void ccw_device_boxed_verify(struct ccw_device *cdev,
 707                                     enum dev_event dev_event)
 708 {
 709         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 710
 711         if (cdev->online) {
 712                 if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
 713                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 714                 else
 715                         ccw_device_online_verify(cdev, dev_event);
 716         } else
 717                 css_schedule_eval(sch->schid);
 718 }
 719
 720 /*
 721  * Got an interrupt for a normal io (state online).
 722  */
 723 static void
 724 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 725 {
 726         struct irb *irb;
 727         int is_cmd;
 728
 729         irb = (struct irb *)&S390_lowcore.irb;
 730         is_cmd = !scsw_is_tm(&irb->scsw);
 731         /* Check for unsolicited interrupt. */
 732         if (!scsw_is_solicited(&irb->scsw)) {
 733                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
 734                     !irb->esw.esw0.erw.cons) {
 735                         /* Unit check but no sense data. Need basic sense. */
 736                         if (ccw_device_do_sense(cdev, irb) != 0)
 737                                 goto call_handler_unsol;
 738                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
 739                         cdev->private->state = DEV_STATE_W4SENSE;
 740                         cdev->private->intparm = 0;
 741                         return;
 742                 }
 743 call_handler_unsol:
 744                 if (cdev->handler)
 745                         cdev->handler (cdev, 0, irb);
 746                 if (cdev->private->flags.doverify)
 747                         ccw_device_online_verify(cdev, 0);
 748                 return;
 749         }
 750         /* Accumulate status and find out if a basic sense is needed. */
 751         ccw_device_accumulate_irb(cdev, irb);
 752         if (is_cmd && cdev->private->flags.dosense) {
 753                 if (ccw_device_do_sense(cdev, irb) == 0) {
 754                         cdev->private->state = DEV_STATE_W4SENSE;
 755                 }
 756                 return;
 757         }
 758         /* Call the handler. */
 759         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 760                 /* Start delayed path verification. */
 761                 ccw_device_online_verify(cdev, 0);
 762 }
 763
 764 /*
 765  * Got an timeout in online state.
 766  */
 767 static void
 768 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 769 {
 770         int ret;
 771
 772         ccw_device_set_timeout(cdev, 0);
 773         cdev->private->iretry = 255;
 774         ret = ccw_device_cancel_halt_clear(cdev);
 775         if (ret == -EBUSY) {
 776                 ccw_device_set_timeout(cdev, 3*HZ);
 777                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 778                 return;
 779         }
 780         if (ret)
 781                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 782         else if (cdev->handler)
 783                 cdev->handler(cdev, cdev->private->intparm,
 784                               ERR_PTR(-ETIMEDOUT));
 785 }
 786
 787 /*
 788  * Got an interrupt for a basic sense.
 789  */
 790 static void
 791 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 792 {
 793         struct irb *irb;
 794
 795         irb = (struct irb *)&S390_lowcore.irb;
 796         /* Check for unsolicited interrupt. */
 797         if (scsw_stctl(&irb->scsw) ==
 798             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 799                 if (scsw_cc(&irb->scsw) == 1)
 800                         /* Basic sense hasn't started. Try again. */
 801                         ccw_device_do_sense(cdev, irb);
 802                 else {
 803                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
 804                                       "interrupt during w4sense...\n",
 805                                       cdev->private->dev_id.ssid,
 806                                       cdev->private->dev_id.devno);
 807                         if (cdev->handler)
 808                                 cdev->handler (cdev, 0, irb);
 809                 }
 810                 return;
 811         }
 812         /*
 813          * Check if a halt or clear has been issued in the meanwhile. If yes,
 814          * only deliver the halt/clear interrupt to the device driver as if it
 815          * had killed the original request.
 816          */
 817         if (scsw_fctl(&irb->scsw) &
 818             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
 819                 cdev->private->flags.dosense = 0;
 820                 memset(&cdev->private->irb, 0, sizeof(struct irb));
 821                 ccw_device_accumulate_irb(cdev, irb);
 822                 goto call_handler;
 823         }
 824         /* Add basic sense info to irb. */
 825         ccw_device_accumulate_basic_sense(cdev, irb);
 826         if (cdev->private->flags.dosense) {
 827                 /* Another basic sense is needed. */
 828                 ccw_device_do_sense(cdev, irb);
 829                 return;
 830         }
 831 call_handler:
 832         cdev->private->state = DEV_STATE_ONLINE;
 833         /* In case sensing interfered with setting the device online */
 834         wake_up(&cdev->private->wait_q);
 835         /* Call the handler. */
 836         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 837                 /* Start delayed path verification. */
 838                 ccw_device_online_verify(cdev, 0);
 839 }
 840
 841 static void
 842 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 843 {
 844         ccw_device_set_timeout(cdev, 0);
 845         /* Start delayed path verification. */
 846         ccw_device_online_verify(cdev, 0);
 847         /* OK, i/o is dead now. Call interrupt handler. */
 848         if (cdev->handler)
 849                 cdev->handler(cdev, cdev->private->intparm,
 850                               ERR_PTR(-EIO));
 851 }
 852
 853 static void
 854 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 855 {
 856         int ret;
 857
 858         ret = ccw_device_cancel_halt_clear(cdev);
 859         if (ret == -EBUSY) {
 860                 ccw_device_set_timeout(cdev, 3*HZ);
 861                 return;
 862         }
 863         /* Start delayed path verification. */
 864         ccw_device_online_verify(cdev, 0);
 865         if (cdev->handler)
 866                 cdev->handler(cdev, cdev->private->intparm,
 867                               ERR_PTR(-EIO));
 868 }
 869
 870 void ccw_device_kill_io(struct ccw_device *cdev)
 871 {
 872         int ret;
 873
 874         cdev->private->iretry = 255;
 875         ret = ccw_device_cancel_halt_clear(cdev);
 876         if (ret == -EBUSY) {
 877                 ccw_device_set_timeout(cdev, 3*HZ);
 878                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 879                 return;
 880         }
 881         /* Start delayed path verification. */
 882         ccw_device_online_verify(cdev, 0);
 883         if (cdev->handler)
 884                 cdev->handler(cdev, cdev->private->intparm,
 885                               ERR_PTR(-EIO));
 886 }
 887
 888 static void
 889 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 890 {
 891         /* Start verification after current task finished. */
 892         cdev->private->flags.doverify = 1;
 893 }
 894
 895 static void
 896 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 897 {
 898         struct subchannel *sch;
 899
 900         sch = to_subchannel(cdev->dev.parent);
 901         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
 902                 /* Couldn't enable the subchannel for i/o. Sick device. */
 903                 return;
 904         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 905         ccw_device_sense_id_start(cdev);
 906 }
 907
 908 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
 909 {
 910         struct subchannel *sch;
 911
 912         if (cdev->private->state != DEV_STATE_DISCONNECTED)
 913                 return;
 914
 915         sch = to_subchannel(cdev->dev.parent);
 916         /* Update some values. */
 917         if (cio_update_schib(sch))
 918                 return;
 919         /*
 920          * The pim, pam, pom values may not be accurate, but they are the best
 921          * we have before performing device selection :/
 922          */
 923         sch->lpm = sch->schib.pmcw.pam & sch->opm;
 924         /*
 925          * Use the initial configuration since we can't be shure that the old
 926          * paths are valid.
 927          */
 928         io_subchannel_init_config(sch);
 929         if (cio_commit_config(sch))
 930                 return;
 931
 932         /* We should also udate ssd info, but this has to wait. */
 933         /* Check if this is another device which appeared on the same sch. */
 934         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
 935                 css_schedule_eval(sch->schid);
 936         else
 937                 ccw_device_start_id(cdev, 0);
 938 }
 939
 940 static void ccw_device_disabled_irq(struct ccw_device *cdev,
 941                                     enum dev_event dev_event)
 942 {
 943         struct subchannel *sch;
 944
 945         sch = to_subchannel(cdev->dev.parent);
 946         /*
 947          * An interrupt in a disabled state means a previous disable was not
 948          * successful - should not happen, but we try to disable again.
 949          */
 950         cio_disable_subchannel(sch);
 951 }
 952
 953 static void
 954 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
 955 {
 956         retry_set_schib(cdev);
 957         cdev->private->state = DEV_STATE_ONLINE;
 958         dev_fsm_event(cdev, dev_event);
 959 }
 960
 961 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
 962                                        enum dev_event dev_event)
 963 {
 964         cmf_retry_copy_block(cdev);
 965         cdev->private->state = DEV_STATE_ONLINE;
 966         dev_fsm_event(cdev, dev_event);
 967 }
 968
 969 static void
 970 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
 971 {
 972         ccw_device_set_timeout(cdev, 0);
 973         cdev->private->state = DEV_STATE_NOT_OPER;
 974         wake_up(&cdev->private->wait_q);
 975 }
 976
 977 static void
 978 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 979 {
 980         int ret;
 981
 982         ret = ccw_device_cancel_halt_clear(cdev);
 983         if (ret == -EBUSY) {
 984                 ccw_device_set_timeout(cdev, HZ/10);
 985         } else {
 986                 cdev->private->state = DEV_STATE_NOT_OPER;
 987                 wake_up(&cdev->private->wait_q);
 988         }
 989 }
 990
 991 /*
 992  * No operation action. This is used e.g. to ignore a timeout event in
 993  * state offline.
 994  */
 995 static void
 996 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
 997 {
 998 }
 999
1000 /*
1001  * device statemachine
1002  */
1003 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1004         [DEV_STATE_NOT_OPER] = {
1005                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1006                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1007                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1008                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1009         },
1010         [DEV_STATE_SENSE_PGID] = {
1011                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1012                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1013                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1014                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1015         },
1016         [DEV_STATE_SENSE_ID] = {
1017                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1018                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1019                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1020                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1021         },
1022         [DEV_STATE_OFFLINE] = {
1023                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1024                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1025                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1026                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
1027         },
1028         [DEV_STATE_VERIFY] = {
1029                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1030                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1031                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1032                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
1033         },
1034         [DEV_STATE_ONLINE] = {
1035                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1036                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1037                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1038                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1039         },
1040         [DEV_STATE_W4SENSE] = {
1041                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1042                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1043                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1044                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1045         },
1046         [DEV_STATE_DISBAND_PGID] = {
1047                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1048                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1049                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1050                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1051         },
1052         [DEV_STATE_BOXED] = {
1053                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1054                 [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
1055                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1056                 [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
1057         },
1058         /* states to wait for i/o completion before doing something */
1059         [DEV_STATE_TIMEOUT_KILL] = {
1060                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1061                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1062                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1063                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1064         },
1065         [DEV_STATE_QUIESCE] = {
1066                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1067                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1068                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1069                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1070         },
1071         /* special states for devices gone not operational */
1072         [DEV_STATE_DISCONNECTED] = {
1073                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1074                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1075                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1076                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1077         },
1078         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1079                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1080                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1081                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1082                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1083         },
1084         [DEV_STATE_CMFCHANGE] = {
1085                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1086                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1087                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1088                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1089         },
1090         [DEV_STATE_CMFUPDATE] = {
1091                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1092                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1093                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1094                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1095         },
1096         [DEV_STATE_STEAL_LOCK] = {
1097                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1098                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1099                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1100                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1101         },
1102 };
1103
1104 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);