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         /* 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                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 413                 else
 414                         ccw_device_set_disconnected(cdev);
 415                 cdev->private->flags.donotify = 0;
 416                 break;
 417         default:
 418                 break;
 419         }
 420
 421         if (cdev->private->flags.donotify) {
 422                 cdev->private->flags.donotify = 0;
 423                 ccw_device_oper_notify(cdev);
 424         }
 425         wake_up(&cdev->private->wait_q);
 426 }
 427
 428 /*
 429  * Start device recognition.
 430  */
 431 void ccw_device_recognition(struct ccw_device *cdev)
 432 {
 433         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 434
 435         /*
 436          * We used to start here with a sense pgid to find out whether a device
 437          * is locked by someone else. Unfortunately, the sense pgid command
 438          * code has other meanings on devices predating the path grouping
 439          * algorithm, so we start with sense id and box the device after an
 440          * timeout (or if sense pgid during path verification detects the device
 441          * is locked, as may happen on newer devices).
 442          */
 443         cdev->private->flags.recog_done = 0;
 444         cdev->private->state = DEV_STATE_SENSE_ID;
 445         if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
 446                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 447                 return;
 448         }
 449         ccw_device_sense_id_start(cdev);
 450 }
 451
 452 /*
 453  * Handle events for states that use the ccw request infrastructure.
 454  */
 455 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
 456 {
 457         switch (e) {
 458         case DEV_EVENT_NOTOPER:
 459                 ccw_request_notoper(cdev);
 460                 break;
 461         case DEV_EVENT_INTERRUPT:
 462                 ccw_request_handler(cdev);
 463                 break;
 464         case DEV_EVENT_TIMEOUT:
 465                 ccw_request_timeout(cdev);
 466                 break;
 467         default:
 468                 break;
 469         }
 470 }
 471
 472 static void ccw_device_report_path_events(struct ccw_device *cdev)
 473 {
 474         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 475         int path_event[8];
 476         int chp, mask;
 477
 478         for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
 479                 path_event[chp] = PE_NONE;
 480                 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
 481                         path_event[chp] |= PE_PATH_GONE;
 482                 if (mask & cdev->private->path_new_mask & sch->vpm)
 483                         path_event[chp] |= PE_PATH_AVAILABLE;
 484                 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
 485                         path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
 486         }
 487         if (cdev->online && cdev->drv->path_event)
 488                 cdev->drv->path_event(cdev, path_event);
 489 }
 490
 491 static void ccw_device_reset_path_events(struct ccw_device *cdev)
 492 {
 493         cdev->private->path_gone_mask = 0;
 494         cdev->private->path_new_mask = 0;
 495         cdev->private->pgid_reset_mask = 0;
 496 }
 497
 498 void
 499 ccw_device_verify_done(struct ccw_device *cdev, int err)
 500 {
 501         struct subchannel *sch;
 502
 503         sch = to_subchannel(cdev->dev.parent);
 504         /* Update schib - pom may have changed. */
 505         if (cio_update_schib(sch)) {
 506                 err = -ENODEV;
 507                 goto callback;
 508         }
 509         /* Update lpm with verified path mask. */
 510         sch->lpm = sch->vpm;
 511         /* Repeat path verification? */
 512         if (cdev->private->flags.doverify) {
 513                 ccw_device_verify_start(cdev);
 514                 return;
 515         }
 516 callback:
 517         switch (err) {
 518         case 0:
 519                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 520                 /* Deliver fake irb to device driver, if needed. */
 521                 if (cdev->private->flags.fake_irb) {
 522                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 523                         cdev->private->irb.scsw.cmd.cc = 1;
 524                         cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC;
 525                         cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND;
 526                         cdev->private->irb.scsw.cmd.stctl =
 527                                 SCSW_STCTL_STATUS_PEND;
 528                         cdev->private->flags.fake_irb = 0;
 529                         if (cdev->handler)
 530                                 cdev->handler(cdev, cdev->private->intparm,
 531                                               &cdev->private->irb);
 532                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 533                 }
 534                 ccw_device_report_path_events(cdev);
 535                 break;
 536         case -ETIME:
 537         case -EUSERS:
 538                 /* Reset oper notify indication after verify error. */
 539                 cdev->private->flags.donotify = 0;
 540                 ccw_device_done(cdev, DEV_STATE_BOXED);
 541                 break;
 542         case -EACCES:
 543                 /* Reset oper notify indication after verify error. */
 544                 cdev->private->flags.donotify = 0;
 545                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
 546                 break;
 547         default:
 548                 /* Reset oper notify indication after verify error. */
 549                 cdev->private->flags.donotify = 0;
 550                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 551                 break;
 552         }
 553         ccw_device_reset_path_events(cdev);
 554 }
 555
 556 /*
 557  * Get device online.
 558  */
 559 int
 560 ccw_device_online(struct ccw_device *cdev)
 561 {
 562         struct subchannel *sch;
 563         int ret;
 564
 565         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 566             (cdev->private->state != DEV_STATE_BOXED))
 567                 return -EINVAL;
 568         sch = to_subchannel(cdev->dev.parent);
 569         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
 570         if (ret != 0) {
 571                 /* Couldn't enable the subchannel for i/o. Sick device. */
 572                 if (ret == -ENODEV)
 573                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 574                 return ret;
 575         }
 576         /* Start initial path verification. */
 577         cdev->private->state = DEV_STATE_VERIFY;
 578         ccw_device_verify_start(cdev);
 579         return 0;
 580 }
 581
 582 void
 583 ccw_device_disband_done(struct ccw_device *cdev, int err)
 584 {
 585         switch (err) {
 586         case 0:
 587                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 588                 break;
 589         case -ETIME:
 590                 ccw_device_done(cdev, DEV_STATE_BOXED);
 591                 break;
 592         default:
 593                 cdev->private->flags.donotify = 0;
 594                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 595                 break;
 596         }
 597 }
 598
 599 /*
 600  * Shutdown device.
 601  */
 602 int
 603 ccw_device_offline(struct ccw_device *cdev)
 604 {
 605         struct subchannel *sch;
 606
 607         /* Allow ccw_device_offline while disconnected. */
 608         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
 609             cdev->private->state == DEV_STATE_NOT_OPER) {
 610                 cdev->private->flags.donotify = 0;
 611                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 612                 return 0;
 613         }
 614         if (cdev->private->state == DEV_STATE_BOXED) {
 615                 ccw_device_done(cdev, DEV_STATE_BOXED);
 616                 return 0;
 617         }
 618         if (ccw_device_is_orphan(cdev)) {
 619                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 620                 return 0;
 621         }
 622         sch = to_subchannel(cdev->dev.parent);
 623         if (cio_update_schib(sch))
 624                 return -ENODEV;
 625         if (scsw_actl(&sch->schib.scsw) != 0)
 626                 return -EBUSY;
 627         if (cdev->private->state != DEV_STATE_ONLINE)
 628                 return -EINVAL;
 629         /* Are we doing path grouping? */
 630         if (!cdev->private->flags.pgroup) {
 631                 /* No, set state offline immediately. */
 632                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 633                 return 0;
 634         }
 635         /* Start Set Path Group commands. */
 636         cdev->private->state = DEV_STATE_DISBAND_PGID;
 637         ccw_device_disband_start(cdev);
 638         return 0;
 639 }
 640
 641 /*
 642  * Handle not operational event in non-special state.
 643  */
 644 static void ccw_device_generic_notoper(struct ccw_device *cdev,
 645                                        enum dev_event dev_event)
 646 {
 647         if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 648                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 649         else
 650                 ccw_device_set_disconnected(cdev);
 651 }
 652
 653 /*
 654  * Handle path verification event in offline state.
 655  */
 656 static void ccw_device_offline_verify(struct ccw_device *cdev,
 657                                       enum dev_event dev_event)
 658 {
 659         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 660
 661         css_schedule_eval(sch->schid);
 662 }
 663
 664 /*
 665  * Handle path verification event.
 666  */
 667 static void
 668 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 669 {
 670         struct subchannel *sch;
 671
 672         if (cdev->private->state == DEV_STATE_W4SENSE) {
 673                 cdev->private->flags.doverify = 1;
 674                 return;
 675         }
 676         sch = to_subchannel(cdev->dev.parent);
 677         /*
 678          * Since we might not just be coming from an interrupt from the
 679          * subchannel we have to update the schib.
 680          */
 681         if (cio_update_schib(sch)) {
 682                 ccw_device_verify_done(cdev, -ENODEV);
 683                 return;
 684         }
 685
 686         if (scsw_actl(&sch->schib.scsw) != 0 ||
 687             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
 688             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
 689                 /*
 690                  * No final status yet or final status not yet delivered
 691                  * to the device driver. Can't do path verification now,
 692                  * delay until final status was delivered.
 693                  */
 694                 cdev->private->flags.doverify = 1;
 695                 return;
 696         }
 697         /* Device is idle, we can do the path verification. */
 698         cdev->private->state = DEV_STATE_VERIFY;
 699         ccw_device_verify_start(cdev);
 700 }
 701
 702 /*
 703  * Handle path verification event in boxed state.
 704  */
 705 static void ccw_device_boxed_verify(struct ccw_device *cdev,
 706                                     enum dev_event dev_event)
 707 {
 708         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 709
 710         if (cdev->online) {
 711                 if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
 712                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 713                 else
 714                         ccw_device_online_verify(cdev, dev_event);
 715         } else
 716                 css_schedule_eval(sch->schid);
 717 }
 718
 719 /*
 720  * Got an interrupt for a normal io (state online).
 721  */
 722 static void
 723 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 724 {
 725         struct irb *irb;
 726         int is_cmd;
 727
 728         irb = (struct irb *)&S390_lowcore.irb;
 729         is_cmd = !scsw_is_tm(&irb->scsw);
 730         /* Check for unsolicited interrupt. */
 731         if (!scsw_is_solicited(&irb->scsw)) {
 732                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
 733                     !irb->esw.esw0.erw.cons) {
 734                         /* Unit check but no sense data. Need basic sense. */
 735                         if (ccw_device_do_sense(cdev, irb) != 0)
 736                                 goto call_handler_unsol;
 737                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
 738                         cdev->private->state = DEV_STATE_W4SENSE;
 739                         cdev->private->intparm = 0;
 740                         return;
 741                 }
 742 call_handler_unsol:
 743                 if (cdev->handler)
 744                         cdev->handler (cdev, 0, irb);
 745                 if (cdev->private->flags.doverify)
 746                         ccw_device_online_verify(cdev, 0);
 747                 return;
 748         }
 749         /* Accumulate status and find out if a basic sense is needed. */
 750         ccw_device_accumulate_irb(cdev, irb);
 751         if (is_cmd && cdev->private->flags.dosense) {
 752                 if (ccw_device_do_sense(cdev, irb) == 0) {
 753                         cdev->private->state = DEV_STATE_W4SENSE;
 754                 }
 755                 return;
 756         }
 757         /* Call the handler. */
 758         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 759                 /* Start delayed path verification. */
 760                 ccw_device_online_verify(cdev, 0);
 761 }
 762
 763 /*
 764  * Got an timeout in online state.
 765  */
 766 static void
 767 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 768 {
 769         int ret;
 770
 771         ccw_device_set_timeout(cdev, 0);
 772         cdev->private->iretry = 255;
 773         ret = ccw_device_cancel_halt_clear(cdev);
 774         if (ret == -EBUSY) {
 775                 ccw_device_set_timeout(cdev, 3*HZ);
 776                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 777                 return;
 778         }
 779         if (ret)
 780                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 781         else if (cdev->handler)
 782                 cdev->handler(cdev, cdev->private->intparm,
 783                               ERR_PTR(-ETIMEDOUT));
 784 }
 785
 786 /*
 787  * Got an interrupt for a basic sense.
 788  */
 789 static void
 790 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 791 {
 792         struct irb *irb;
 793
 794         irb = (struct irb *)&S390_lowcore.irb;
 795         /* Check for unsolicited interrupt. */
 796         if (scsw_stctl(&irb->scsw) ==
 797             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 798                 if (scsw_cc(&irb->scsw) == 1)
 799                         /* Basic sense hasn't started. Try again. */
 800                         ccw_device_do_sense(cdev, irb);
 801                 else {
 802                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
 803                                       "interrupt during w4sense...\n",
 804                                       cdev->private->dev_id.ssid,
 805                                       cdev->private->dev_id.devno);
 806                         if (cdev->handler)
 807                                 cdev->handler (cdev, 0, irb);
 808                 }
 809                 return;
 810         }
 811         /*
 812          * Check if a halt or clear has been issued in the meanwhile. If yes,
 813          * only deliver the halt/clear interrupt to the device driver as if it
 814          * had killed the original request.
 815          */
 816         if (scsw_fctl(&irb->scsw) &
 817             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
 818                 cdev->private->flags.dosense = 0;
 819                 memset(&cdev->private->irb, 0, sizeof(struct irb));
 820                 ccw_device_accumulate_irb(cdev, irb);
 821                 goto call_handler;
 822         }
 823         /* Add basic sense info to irb. */
 824         ccw_device_accumulate_basic_sense(cdev, irb);
 825         if (cdev->private->flags.dosense) {
 826                 /* Another basic sense is needed. */
 827                 ccw_device_do_sense(cdev, irb);
 828                 return;
 829         }
 830 call_handler:
 831         cdev->private->state = DEV_STATE_ONLINE;
 832         /* In case sensing interfered with setting the device online */
 833         wake_up(&cdev->private->wait_q);
 834         /* Call the handler. */
 835         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 836                 /* Start delayed path verification. */
 837                 ccw_device_online_verify(cdev, 0);
 838 }
 839
 840 static void
 841 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 842 {
 843         struct subchannel *sch;
 844
 845         sch = to_subchannel(cdev->dev.parent);
 846         ccw_device_set_timeout(cdev, 0);
 847         /* Start delayed path verification. */
 848         ccw_device_online_verify(cdev, 0);
 849         /* OK, i/o is dead now. Call interrupt handler. */
 850         if (cdev->handler)
 851                 cdev->handler(cdev, cdev->private->intparm,
 852                               ERR_PTR(-EIO));
 853 }
 854
 855 static void
 856 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 857 {
 858         int ret;
 859
 860         ret = ccw_device_cancel_halt_clear(cdev);
 861         if (ret == -EBUSY) {
 862                 ccw_device_set_timeout(cdev, 3*HZ);
 863                 return;
 864         }
 865         /* Start delayed path verification. */
 866         ccw_device_online_verify(cdev, 0);
 867         if (cdev->handler)
 868                 cdev->handler(cdev, cdev->private->intparm,
 869                               ERR_PTR(-EIO));
 870 }
 871
 872 void ccw_device_kill_io(struct ccw_device *cdev)
 873 {
 874         int ret;
 875
 876         cdev->private->iretry = 255;
 877         ret = ccw_device_cancel_halt_clear(cdev);
 878         if (ret == -EBUSY) {
 879                 ccw_device_set_timeout(cdev, 3*HZ);
 880                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 881                 return;
 882         }
 883         /* Start delayed path verification. */
 884         ccw_device_online_verify(cdev, 0);
 885         if (cdev->handler)
 886                 cdev->handler(cdev, cdev->private->intparm,
 887                               ERR_PTR(-EIO));
 888 }
 889
 890 static void
 891 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 892 {
 893         /* Start verification after current task finished. */
 894         cdev->private->flags.doverify = 1;
 895 }
 896
 897 static void
 898 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 899 {
 900         struct subchannel *sch;
 901
 902         sch = to_subchannel(cdev->dev.parent);
 903         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
 904                 /* Couldn't enable the subchannel for i/o. Sick device. */
 905                 return;
 906         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 907         ccw_device_sense_id_start(cdev);
 908 }
 909
 910 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
 911 {
 912         struct subchannel *sch;
 913
 914         if (cdev->private->state != DEV_STATE_DISCONNECTED)
 915                 return;
 916
 917         sch = to_subchannel(cdev->dev.parent);
 918         /* Update some values. */
 919         if (cio_update_schib(sch))
 920                 return;
 921         /*
 922          * The pim, pam, pom values may not be accurate, but they are the best
 923          * we have before performing device selection :/
 924          */
 925         sch->lpm = sch->schib.pmcw.pam & sch->opm;
 926         /*
 927          * Use the initial configuration since we can't be shure that the old
 928          * paths are valid.
 929          */
 930         io_subchannel_init_config(sch);
 931         if (cio_commit_config(sch))
 932                 return;
 933
 934         /* We should also udate ssd info, but this has to wait. */
 935         /* Check if this is another device which appeared on the same sch. */
 936         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
 937                 css_schedule_eval(sch->schid);
 938         else
 939                 ccw_device_start_id(cdev, 0);
 940 }
 941
 942 static void ccw_device_disabled_irq(struct ccw_device *cdev,
 943                                     enum dev_event dev_event)
 944 {
 945         struct subchannel *sch;
 946
 947         sch = to_subchannel(cdev->dev.parent);
 948         /*
 949          * An interrupt in a disabled state means a previous disable was not
 950          * successful - should not happen, but we try to disable again.
 951          */
 952         cio_disable_subchannel(sch);
 953 }
 954
 955 static void
 956 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
 957 {
 958         retry_set_schib(cdev);
 959         cdev->private->state = DEV_STATE_ONLINE;
 960         dev_fsm_event(cdev, dev_event);
 961 }
 962
 963 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
 964                                        enum dev_event dev_event)
 965 {
 966         cmf_retry_copy_block(cdev);
 967         cdev->private->state = DEV_STATE_ONLINE;
 968         dev_fsm_event(cdev, dev_event);
 969 }
 970
 971 static void
 972 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
 973 {
 974         ccw_device_set_timeout(cdev, 0);
 975         cdev->private->state = DEV_STATE_NOT_OPER;
 976         wake_up(&cdev->private->wait_q);
 977 }
 978
 979 static void
 980 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 981 {
 982         int ret;
 983
 984         ret = ccw_device_cancel_halt_clear(cdev);
 985         if (ret == -EBUSY) {
 986                 ccw_device_set_timeout(cdev, HZ/10);
 987         } else {
 988                 cdev->private->state = DEV_STATE_NOT_OPER;
 989                 wake_up(&cdev->private->wait_q);
 990         }
 991 }
 992
 993 /*
 994  * No operation action. This is used e.g. to ignore a timeout event in
 995  * state offline.
 996  */
 997 static void
 998 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
 999 {
1000 }
1001
1002 /*
1003  * device statemachine
1004  */
1005 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1006         [DEV_STATE_NOT_OPER] = {
1007                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1008                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1009                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1010                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1011         },
1012         [DEV_STATE_SENSE_PGID] = {
1013                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1014                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1015                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1016                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1017         },
1018         [DEV_STATE_SENSE_ID] = {
1019                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1020                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1021                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1022                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1023         },
1024         [DEV_STATE_OFFLINE] = {
1025                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1026                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1027                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1028                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
1029         },
1030         [DEV_STATE_VERIFY] = {
1031                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1032                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1033                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1034                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
1035         },
1036         [DEV_STATE_ONLINE] = {
1037                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1038                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1039                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1040                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1041         },
1042         [DEV_STATE_W4SENSE] = {
1043                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1044                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1045                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1046                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1047         },
1048         [DEV_STATE_DISBAND_PGID] = {
1049                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1050                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1051                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1052                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1053         },
1054         [DEV_STATE_BOXED] = {
1055                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1056                 [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
1057                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1058                 [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
1059         },
1060         /* states to wait for i/o completion before doing something */
1061         [DEV_STATE_TIMEOUT_KILL] = {
1062                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1063                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1064                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1065                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1066         },
1067         [DEV_STATE_QUIESCE] = {
1068                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1069                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1070                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1071                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1072         },
1073         /* special states for devices gone not operational */
1074         [DEV_STATE_DISCONNECTED] = {
1075                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1076                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1077                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1078                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1079         },
1080         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1081                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1082                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1083                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1084                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1085         },
1086         [DEV_STATE_CMFCHANGE] = {
1087                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1088                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1089                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1090                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1091         },
1092         [DEV_STATE_CMFUPDATE] = {
1093                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1094                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1095                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1096                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1097         },
1098         [DEV_STATE_STEAL_LOCK] = {
1099                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1100                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1101                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1102                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1103         },
1104 };
1105
1106 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);