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         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
 353                 /* Reenable channel measurements, if needed. */
 354                 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
 355                 return;
 356         }
 357         /* Driver doesn't want device back. */
 358         ccw_device_set_notoper(cdev);
 359         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 360 }
 361
 362 /*
 363  * Finished with online/offline processing.
 364  */
 365 static void
 366 ccw_device_done(struct ccw_device *cdev, int state)
 367 {
 368         struct subchannel *sch;
 369
 370         sch = to_subchannel(cdev->dev.parent);
 371
 372         ccw_device_set_timeout(cdev, 0);
 373
 374         if (state != DEV_STATE_ONLINE)
 375                 cio_disable_subchannel(sch);
 376
 377         /* Reset device status. */
 378         memset(&cdev->private->irb, 0, sizeof(struct irb));
 379
 380         cdev->private->state = state;
 381
 382         switch (state) {
 383         case DEV_STATE_BOXED:
 384                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
 385                               cdev->private->dev_id.devno, sch->schid.sch_no);
 386                 if (cdev->online &&
 387                     ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
 388                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 389                 cdev->private->flags.donotify = 0;
 390                 break;
 391         case DEV_STATE_NOT_OPER:
 392                 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
 393                               cdev->private->dev_id.devno, sch->schid.sch_no);
 394                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 395                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 396                 else
 397                         ccw_device_set_disconnected(cdev);
 398                 cdev->private->flags.donotify = 0;
 399                 break;
 400         case DEV_STATE_DISCONNECTED:
 401                 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
 402                               "%04x\n", cdev->private->dev_id.devno,
 403                               sch->schid.sch_no);
 404                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
 405                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 406                 else
 407                         ccw_device_set_disconnected(cdev);
 408                 cdev->private->flags.donotify = 0;
 409                 break;
 410         default:
 411                 break;
 412         }
 413
 414         if (cdev->private->flags.donotify) {
 415                 cdev->private->flags.donotify = 0;
 416                 ccw_device_oper_notify(cdev);
 417         }
 418         wake_up(&cdev->private->wait_q);
 419 }
 420
 421 /*
 422  * Start device recognition.
 423  */
 424 void ccw_device_recognition(struct ccw_device *cdev)
 425 {
 426         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 427
 428         /*
 429          * We used to start here with a sense pgid to find out whether a device
 430          * is locked by someone else. Unfortunately, the sense pgid command
 431          * code has other meanings on devices predating the path grouping
 432          * algorithm, so we start with sense id and box the device after an
 433          * timeout (or if sense pgid during path verification detects the device
 434          * is locked, as may happen on newer devices).
 435          */
 436         cdev->private->flags.recog_done = 0;
 437         cdev->private->state = DEV_STATE_SENSE_ID;
 438         if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
 439                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 440                 return;
 441         }
 442         ccw_device_sense_id_start(cdev);
 443 }
 444
 445 /*
 446  * Handle events for states that use the ccw request infrastructure.
 447  */
 448 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
 449 {
 450         switch (e) {
 451         case DEV_EVENT_NOTOPER:
 452                 ccw_request_notoper(cdev);
 453                 break;
 454         case DEV_EVENT_INTERRUPT:
 455                 ccw_request_handler(cdev);
 456                 break;
 457         case DEV_EVENT_TIMEOUT:
 458                 ccw_request_timeout(cdev);
 459                 break;
 460         default:
 461                 break;
 462         }
 463 }
 464
 465 void
 466 ccw_device_verify_done(struct ccw_device *cdev, int err)
 467 {
 468         struct subchannel *sch;
 469
 470         sch = to_subchannel(cdev->dev.parent);
 471         /* Update schib - pom may have changed. */
 472         if (cio_update_schib(sch)) {
 473                 err = -ENODEV;
 474                 goto callback;
 475         }
 476         /* Update lpm with verified path mask. */
 477         sch->lpm = sch->vpm;
 478         /* Repeat path verification? */
 479         if (cdev->private->flags.doverify) {
 480                 ccw_device_verify_start(cdev);
 481                 return;
 482         }
 483 callback:
 484         switch (err) {
 485         case 0:
 486                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 487                 /* Deliver fake irb to device driver, if needed. */
 488                 if (cdev->private->flags.fake_irb) {
 489                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 490                         cdev->private->irb.scsw.cmd.cc = 1;
 491                         cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC;
 492                         cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND;
 493                         cdev->private->irb.scsw.cmd.stctl =
 494                                 SCSW_STCTL_STATUS_PEND;
 495                         cdev->private->flags.fake_irb = 0;
 496                         if (cdev->handler)
 497                                 cdev->handler(cdev, cdev->private->intparm,
 498                                               &cdev->private->irb);
 499                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 500                 }
 501                 break;
 502         case -ETIME:
 503         case -EUSERS:
 504                 /* Reset oper notify indication after verify error. */
 505                 cdev->private->flags.donotify = 0;
 506                 ccw_device_done(cdev, DEV_STATE_BOXED);
 507                 break;
 508         case -EACCES:
 509                 /* Reset oper notify indication after verify error. */
 510                 cdev->private->flags.donotify = 0;
 511                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
 512                 break;
 513         default:
 514                 /* Reset oper notify indication after verify error. */
 515                 cdev->private->flags.donotify = 0;
 516                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 517                 break;
 518         }
 519 }
 520
 521 /*
 522  * Get device online.
 523  */
 524 int
 525 ccw_device_online(struct ccw_device *cdev)
 526 {
 527         struct subchannel *sch;
 528         int ret;
 529
 530         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 531             (cdev->private->state != DEV_STATE_BOXED))
 532                 return -EINVAL;
 533         sch = to_subchannel(cdev->dev.parent);
 534         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
 535         if (ret != 0) {
 536                 /* Couldn't enable the subchannel for i/o. Sick device. */
 537                 if (ret == -ENODEV)
 538                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 539                 return ret;
 540         }
 541         /* Start initial path verification. */
 542         cdev->private->state = DEV_STATE_VERIFY;
 543         ccw_device_verify_start(cdev);
 544         return 0;
 545 }
 546
 547 void
 548 ccw_device_disband_done(struct ccw_device *cdev, int err)
 549 {
 550         switch (err) {
 551         case 0:
 552                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 553                 break;
 554         case -ETIME:
 555                 ccw_device_done(cdev, DEV_STATE_BOXED);
 556                 break;
 557         default:
 558                 cdev->private->flags.donotify = 0;
 559                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 560                 break;
 561         }
 562 }
 563
 564 /*
 565  * Shutdown device.
 566  */
 567 int
 568 ccw_device_offline(struct ccw_device *cdev)
 569 {
 570         struct subchannel *sch;
 571
 572         /* Allow ccw_device_offline while disconnected. */
 573         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
 574             cdev->private->state == DEV_STATE_NOT_OPER) {
 575                 cdev->private->flags.donotify = 0;
 576                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 577                 return 0;
 578         }
 579         if (cdev->private->state == DEV_STATE_BOXED) {
 580                 ccw_device_done(cdev, DEV_STATE_BOXED);
 581                 return 0;
 582         }
 583         if (ccw_device_is_orphan(cdev)) {
 584                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 585                 return 0;
 586         }
 587         sch = to_subchannel(cdev->dev.parent);
 588         if (cio_update_schib(sch))
 589                 return -ENODEV;
 590         if (scsw_actl(&sch->schib.scsw) != 0)
 591                 return -EBUSY;
 592         if (cdev->private->state != DEV_STATE_ONLINE)
 593                 return -EINVAL;
 594         /* Are we doing path grouping? */
 595         if (!cdev->private->flags.pgroup) {
 596                 /* No, set state offline immediately. */
 597                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 598                 return 0;
 599         }
 600         /* Start Set Path Group commands. */
 601         cdev->private->state = DEV_STATE_DISBAND_PGID;
 602         ccw_device_disband_start(cdev);
 603         return 0;
 604 }
 605
 606 /*
 607  * Handle not operational event in non-special state.
 608  */
 609 static void ccw_device_generic_notoper(struct ccw_device *cdev,
 610                                        enum dev_event dev_event)
 611 {
 612         if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 613                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 614         else
 615                 ccw_device_set_disconnected(cdev);
 616 }
 617
 618 /*
 619  * Handle path verification event in offline state.
 620  */
 621 static void ccw_device_offline_verify(struct ccw_device *cdev,
 622                                       enum dev_event dev_event)
 623 {
 624         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 625
 626         css_schedule_eval(sch->schid);
 627 }
 628
 629 /*
 630  * Handle path verification event.
 631  */
 632 static void
 633 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 634 {
 635         struct subchannel *sch;
 636
 637         if (cdev->private->state == DEV_STATE_W4SENSE) {
 638                 cdev->private->flags.doverify = 1;
 639                 return;
 640         }
 641         sch = to_subchannel(cdev->dev.parent);
 642         /*
 643          * Since we might not just be coming from an interrupt from the
 644          * subchannel we have to update the schib.
 645          */
 646         if (cio_update_schib(sch)) {
 647                 ccw_device_verify_done(cdev, -ENODEV);
 648                 return;
 649         }
 650
 651         if (scsw_actl(&sch->schib.scsw) != 0 ||
 652             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
 653             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
 654                 /*
 655                  * No final status yet or final status not yet delivered
 656                  * to the device driver. Can't do path verfication now,
 657                  * delay until final status was delivered.
 658                  */
 659                 cdev->private->flags.doverify = 1;
 660                 return;
 661         }
 662         /* Device is idle, we can do the path verification. */
 663         cdev->private->state = DEV_STATE_VERIFY;
 664         ccw_device_verify_start(cdev);
 665 }
 666
 667 /*
 668  * Handle path verification event in boxed state.
 669  */
 670 static void ccw_device_boxed_verify(struct ccw_device *cdev,
 671                                     enum dev_event dev_event)
 672 {
 673         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 674
 675         if (cdev->online) {
 676                 if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
 677                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 678                 else
 679                         ccw_device_online_verify(cdev, dev_event);
 680         } else
 681                 css_schedule_eval(sch->schid);
 682 }
 683
 684 /*
 685  * Got an interrupt for a normal io (state online).
 686  */
 687 static void
 688 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 689 {
 690         struct irb *irb;
 691         int is_cmd;
 692
 693         irb = (struct irb *)&S390_lowcore.irb;
 694         is_cmd = !scsw_is_tm(&irb->scsw);
 695         /* Check for unsolicited interrupt. */
 696         if (!scsw_is_solicited(&irb->scsw)) {
 697                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
 698                     !irb->esw.esw0.erw.cons) {
 699                         /* Unit check but no sense data. Need basic sense. */
 700                         if (ccw_device_do_sense(cdev, irb) != 0)
 701                                 goto call_handler_unsol;
 702                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
 703                         cdev->private->state = DEV_STATE_W4SENSE;
 704                         cdev->private->intparm = 0;
 705                         return;
 706                 }
 707 call_handler_unsol:
 708                 if (cdev->handler)
 709                         cdev->handler (cdev, 0, irb);
 710                 if (cdev->private->flags.doverify)
 711                         ccw_device_online_verify(cdev, 0);
 712                 return;
 713         }
 714         /* Accumulate status and find out if a basic sense is needed. */
 715         ccw_device_accumulate_irb(cdev, irb);
 716         if (is_cmd && cdev->private->flags.dosense) {
 717                 if (ccw_device_do_sense(cdev, irb) == 0) {
 718                         cdev->private->state = DEV_STATE_W4SENSE;
 719                 }
 720                 return;
 721         }
 722         /* Call the handler. */
 723         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 724                 /* Start delayed path verification. */
 725                 ccw_device_online_verify(cdev, 0);
 726 }
 727
 728 /*
 729  * Got an timeout in online state.
 730  */
 731 static void
 732 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 733 {
 734         int ret;
 735
 736         ccw_device_set_timeout(cdev, 0);
 737         ret = ccw_device_cancel_halt_clear(cdev);
 738         if (ret == -EBUSY) {
 739                 ccw_device_set_timeout(cdev, 3*HZ);
 740                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 741                 return;
 742         }
 743         if (ret == -ENODEV)
 744                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 745         else if (cdev->handler)
 746                 cdev->handler(cdev, cdev->private->intparm,
 747                               ERR_PTR(-ETIMEDOUT));
 748 }
 749
 750 /*
 751  * Got an interrupt for a basic sense.
 752  */
 753 static void
 754 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 755 {
 756         struct irb *irb;
 757
 758         irb = (struct irb *)&S390_lowcore.irb;
 759         /* Check for unsolicited interrupt. */
 760         if (scsw_stctl(&irb->scsw) ==
 761             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 762                 if (scsw_cc(&irb->scsw) == 1)
 763                         /* Basic sense hasn't started. Try again. */
 764                         ccw_device_do_sense(cdev, irb);
 765                 else {
 766                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
 767                                       "interrupt during w4sense...\n",
 768                                       cdev->private->dev_id.ssid,
 769                                       cdev->private->dev_id.devno);
 770                         if (cdev->handler)
 771                                 cdev->handler (cdev, 0, irb);
 772                 }
 773                 return;
 774         }
 775         /*
 776          * Check if a halt or clear has been issued in the meanwhile. If yes,
 777          * only deliver the halt/clear interrupt to the device driver as if it
 778          * had killed the original request.
 779          */
 780         if (scsw_fctl(&irb->scsw) &
 781             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
 782                 cdev->private->flags.dosense = 0;
 783                 memset(&cdev->private->irb, 0, sizeof(struct irb));
 784                 ccw_device_accumulate_irb(cdev, irb);
 785                 goto call_handler;
 786         }
 787         /* Add basic sense info to irb. */
 788         ccw_device_accumulate_basic_sense(cdev, irb);
 789         if (cdev->private->flags.dosense) {
 790                 /* Another basic sense is needed. */
 791                 ccw_device_do_sense(cdev, irb);
 792                 return;
 793         }
 794 call_handler:
 795         cdev->private->state = DEV_STATE_ONLINE;
 796         /* In case sensing interfered with setting the device online */
 797         wake_up(&cdev->private->wait_q);
 798         /* Call the handler. */
 799         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 800                 /* Start delayed path verification. */
 801                 ccw_device_online_verify(cdev, 0);
 802 }
 803
 804 static void
 805 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 806 {
 807         struct subchannel *sch;
 808
 809         sch = to_subchannel(cdev->dev.parent);
 810         ccw_device_set_timeout(cdev, 0);
 811         /* Start delayed path verification. */
 812         ccw_device_online_verify(cdev, 0);
 813         /* OK, i/o is dead now. Call interrupt handler. */
 814         if (cdev->handler)
 815                 cdev->handler(cdev, cdev->private->intparm,
 816                               ERR_PTR(-EIO));
 817 }
 818
 819 static void
 820 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 821 {
 822         int ret;
 823
 824         ret = ccw_device_cancel_halt_clear(cdev);
 825         if (ret == -EBUSY) {
 826                 ccw_device_set_timeout(cdev, 3*HZ);
 827                 return;
 828         }
 829         /* Start delayed path verification. */
 830         ccw_device_online_verify(cdev, 0);
 831         if (cdev->handler)
 832                 cdev->handler(cdev, cdev->private->intparm,
 833                               ERR_PTR(-EIO));
 834 }
 835
 836 void ccw_device_kill_io(struct ccw_device *cdev)
 837 {
 838         int ret;
 839
 840         ret = ccw_device_cancel_halt_clear(cdev);
 841         if (ret == -EBUSY) {
 842                 ccw_device_set_timeout(cdev, 3*HZ);
 843                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 844                 return;
 845         }
 846         /* Start delayed path verification. */
 847         ccw_device_online_verify(cdev, 0);
 848         if (cdev->handler)
 849                 cdev->handler(cdev, cdev->private->intparm,
 850                               ERR_PTR(-EIO));
 851 }
 852
 853 static void
 854 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 855 {
 856         /* Start verification after current task finished. */
 857         cdev->private->flags.doverify = 1;
 858 }
 859
 860 static void
 861 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 862 {
 863         struct subchannel *sch;
 864
 865         sch = to_subchannel(cdev->dev.parent);
 866         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
 867                 /* Couldn't enable the subchannel for i/o. Sick device. */
 868                 return;
 869         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 870         ccw_device_sense_id_start(cdev);
 871 }
 872
 873 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
 874 {
 875         struct subchannel *sch;
 876
 877         if (cdev->private->state != DEV_STATE_DISCONNECTED)
 878                 return;
 879
 880         sch = to_subchannel(cdev->dev.parent);
 881         /* Update some values. */
 882         if (cio_update_schib(sch))
 883                 return;
 884         /*
 885          * The pim, pam, pom values may not be accurate, but they are the best
 886          * we have before performing device selection :/
 887          */
 888         sch->lpm = sch->schib.pmcw.pam & sch->opm;
 889         /*
 890          * Use the initial configuration since we can't be shure that the old
 891          * paths are valid.
 892          */
 893         io_subchannel_init_config(sch);
 894         if (cio_commit_config(sch))
 895                 return;
 896
 897         /* We should also udate ssd info, but this has to wait. */
 898         /* Check if this is another device which appeared on the same sch. */
 899         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
 900                 css_schedule_eval(sch->schid);
 901         else
 902                 ccw_device_start_id(cdev, 0);
 903 }
 904
 905 static void ccw_device_disabled_irq(struct ccw_device *cdev,
 906                                     enum dev_event dev_event)
 907 {
 908         struct subchannel *sch;
 909
 910         sch = to_subchannel(cdev->dev.parent);
 911         /*
 912          * An interrupt in a disabled state means a previous disable was not
 913          * successful - should not happen, but we try to disable again.
 914          */
 915         cio_disable_subchannel(sch);
 916 }
 917
 918 static void
 919 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
 920 {
 921         retry_set_schib(cdev);
 922         cdev->private->state = DEV_STATE_ONLINE;
 923         dev_fsm_event(cdev, dev_event);
 924 }
 925
 926 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
 927                                        enum dev_event dev_event)
 928 {
 929         cmf_retry_copy_block(cdev);
 930         cdev->private->state = DEV_STATE_ONLINE;
 931         dev_fsm_event(cdev, dev_event);
 932 }
 933
 934 static void
 935 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
 936 {
 937         ccw_device_set_timeout(cdev, 0);
 938         cdev->private->state = DEV_STATE_NOT_OPER;
 939         wake_up(&cdev->private->wait_q);
 940 }
 941
 942 static void
 943 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 944 {
 945         int ret;
 946
 947         ret = ccw_device_cancel_halt_clear(cdev);
 948         if (ret == -EBUSY) {
 949                 ccw_device_set_timeout(cdev, HZ/10);
 950         } else {
 951                 cdev->private->state = DEV_STATE_NOT_OPER;
 952                 wake_up(&cdev->private->wait_q);
 953         }
 954 }
 955
 956 /*
 957  * No operation action. This is used e.g. to ignore a timeout event in
 958  * state offline.
 959  */
 960 static void
 961 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
 962 {
 963 }
 964
 965 /*
 966  * device statemachine
 967  */
 968 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
 969         [DEV_STATE_NOT_OPER] = {
 970                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
 971                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
 972                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
 973                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 974         },
 975         [DEV_STATE_SENSE_PGID] = {
 976                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 977                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 978                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 979                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 980         },
 981         [DEV_STATE_SENSE_ID] = {
 982                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 983                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 984                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 985                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 986         },
 987         [DEV_STATE_OFFLINE] = {
 988                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
 989                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
 990                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
 991                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
 992         },
 993         [DEV_STATE_VERIFY] = {
 994                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 995                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 996                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 997                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
 998         },
 999         [DEV_STATE_ONLINE] = {
1000                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1001                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1002                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1003                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1004         },
1005         [DEV_STATE_W4SENSE] = {
1006                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1007                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1008                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1009                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1010         },
1011         [DEV_STATE_DISBAND_PGID] = {
1012                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1013                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1014                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1015                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1016         },
1017         [DEV_STATE_BOXED] = {
1018                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1019                 [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
1020                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1021                 [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
1022         },
1023         /* states to wait for i/o completion before doing something */
1024         [DEV_STATE_TIMEOUT_KILL] = {
1025                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1026                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1027                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1028                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1029         },
1030         [DEV_STATE_QUIESCE] = {
1031                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1032                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1033                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1034                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1035         },
1036         /* special states for devices gone not operational */
1037         [DEV_STATE_DISCONNECTED] = {
1038                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1039                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1040                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1041                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1042         },
1043         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
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_CMFCHANGE] = {
1050                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1051                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1052                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1053                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1054         },
1055         [DEV_STATE_CMFUPDATE] = {
1056                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1057                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1058                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1059                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1060         },
1061         [DEV_STATE_STEAL_LOCK] = {
1062                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1063                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1064                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1065                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1066         },
1067 };
1068
1069 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);