drivers/s390/cio/device_fsm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   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(sch->schid, &schib);
  49
  50         printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
  51                "device information:\n", get_tod_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 ==
  71                     &private->dma_area->sense_ccw ||
  72                     (void *)(addr_t)orb->cmd.cpa ==
  73                     cdev->private->dma_area->iccws)
  74                         printk(KERN_WARNING "cio: last channel program "
  75                                "(intern):\n");
  76                 else
  77                         printk(KERN_WARNING "cio: last channel program:\n");
  78
  79                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  80                                (void *)(addr_t)orb->cmd.cpa,
  81                                sizeof(struct ccw1), 0);
  82         }
  83         printk(KERN_WARNING "cio: ccw device state: %d\n",
  84                cdev->private->state);
  85         printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
  86         printk(KERN_WARNING "cio: schib:\n");
  87         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  88                        &schib, sizeof(schib), 0);
  89         printk(KERN_WARNING "cio: ccw device flags:\n");
  90         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  91                        &cdev->private->flags, sizeof(cdev->private->flags), 0);
  92 }
  93
  94 /*
  95  * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
  96  */
  97 void
  98 ccw_device_timeout(struct timer_list *t)
  99 {
 100         struct ccw_device_private *priv = from_timer(priv, t, timer);
 101         struct ccw_device *cdev = priv->cdev;
 102
 103         spin_lock_irq(cdev->ccwlock);
 104         if (timeout_log_enabled)
 105                 ccw_timeout_log(cdev);
 106         dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
 107         spin_unlock_irq(cdev->ccwlock);
 108 }
 109
 110 /*
 111  * Set timeout
 112  */
 113 void
 114 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
 115 {
 116         if (expires == 0) {
 117                 del_timer(&cdev->private->timer);
 118                 return;
 119         }
 120         if (timer_pending(&cdev->private->timer)) {
 121                 if (mod_timer(&cdev->private->timer, jiffies + expires))
 122                         return;
 123         }
 124         cdev->private->timer.expires = jiffies + expires;
 125         add_timer(&cdev->private->timer);
 126 }
 127
 128 int
 129 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
 130 {
 131         struct subchannel *sch;
 132         int ret;
 133
 134         sch = to_subchannel(cdev->dev.parent);
 135         ret = cio_cancel_halt_clear(sch, &cdev->private->iretry);
 136
 137         if (ret == -EIO)
 138                 CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
 139                               cdev->private->dev_id.ssid,
 140                               cdev->private->dev_id.devno);
 141
 142         return ret;
 143 }
 144
 145 void ccw_device_update_sense_data(struct ccw_device *cdev)
 146 {
 147         memset(&cdev->id, 0, sizeof(cdev->id));
 148         cdev->id.cu_type = cdev->private->dma_area->senseid.cu_type;
 149         cdev->id.cu_model = cdev->private->dma_area->senseid.cu_model;
 150         cdev->id.dev_type = cdev->private->dma_area->senseid.dev_type;
 151         cdev->id.dev_model = cdev->private->dma_area->senseid.dev_model;
 152 }
 153
 154 int ccw_device_test_sense_data(struct ccw_device *cdev)
 155 {
 156         return cdev->id.cu_type ==
 157                 cdev->private->dma_area->senseid.cu_type &&
 158                 cdev->id.cu_model ==
 159                 cdev->private->dma_area->senseid.cu_model &&
 160                 cdev->id.dev_type ==
 161                 cdev->private->dma_area->senseid.dev_type &&
 162                 cdev->id.dev_model ==
 163                 cdev->private->dma_area->senseid.dev_model;
 164 }
 165
 166 /*
 167  * The machine won't give us any notification by machine check if a chpid has
 168  * been varied online on the SE so we have to find out by magic (i. e. driving
 169  * the channel subsystem to device selection and updating our path masks).
 170  */
 171 static void
 172 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
 173 {
 174         int mask, i;
 175         struct chp_id chpid;
 176
 177         chp_id_init(&chpid);
 178         for (i = 0; i<8; i++) {
 179                 mask = 0x80 >> i;
 180                 if (!(sch->lpm & mask))
 181                         continue;
 182                 if (old_lpm & mask)
 183                         continue;
 184                 chpid.id = sch->schib.pmcw.chpid[i];
 185                 if (!chp_is_registered(chpid))
 186                         css_schedule_eval_all();
 187         }
 188 }
 189
 190 /*
 191  * Stop device recognition.
 192  */
 193 static void
 194 ccw_device_recog_done(struct ccw_device *cdev, int state)
 195 {
 196         struct subchannel *sch;
 197         int old_lpm;
 198
 199         sch = to_subchannel(cdev->dev.parent);
 200
 201         if (cio_disable_subchannel(sch))
 202                 state = DEV_STATE_NOT_OPER;
 203         /*
 204          * Now that we tried recognition, we have performed device selection
 205          * through ssch() and the path information is up to date.
 206          */
 207         old_lpm = sch->lpm;
 208
 209         /* Check since device may again have become not operational. */
 210         if (cio_update_schib(sch))
 211                 state = DEV_STATE_NOT_OPER;
 212         else
 213                 sch->lpm = sch->schib.pmcw.pam & sch->opm;
 214
 215         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
 216                 /* Force reprobe on all chpids. */
 217                 old_lpm = 0;
 218         if (sch->lpm != old_lpm)
 219                 __recover_lost_chpids(sch, old_lpm);
 220         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
 221             (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
 222                 cdev->private->flags.recog_done = 1;
 223                 cdev->private->state = DEV_STATE_DISCONNECTED;
 224                 wake_up(&cdev->private->wait_q);
 225                 return;
 226         }
 227         if (cdev->private->flags.resuming) {
 228                 cdev->private->state = state;
 229                 cdev->private->flags.recog_done = 1;
 230                 wake_up(&cdev->private->wait_q);
 231                 return;
 232         }
 233         switch (state) {
 234         case DEV_STATE_NOT_OPER:
 235                 break;
 236         case DEV_STATE_OFFLINE:
 237                 if (!cdev->online) {
 238                         ccw_device_update_sense_data(cdev);
 239                         break;
 240                 }
 241                 cdev->private->state = DEV_STATE_OFFLINE;
 242                 cdev->private->flags.recog_done = 1;
 243                 if (ccw_device_test_sense_data(cdev)) {
 244                         cdev->private->flags.donotify = 1;
 245                         ccw_device_online(cdev);
 246                         wake_up(&cdev->private->wait_q);
 247                 } else {
 248                         ccw_device_update_sense_data(cdev);
 249                         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 250                 }
 251                 return;
 252         case DEV_STATE_BOXED:
 253                 if (cdev->id.cu_type != 0) { /* device was recognized before */
 254                         cdev->private->flags.recog_done = 1;
 255                         cdev->private->state = DEV_STATE_BOXED;
 256                         wake_up(&cdev->private->wait_q);
 257                         return;
 258                 }
 259                 break;
 260         }
 261         cdev->private->state = state;
 262         io_subchannel_recog_done(cdev);
 263         wake_up(&cdev->private->wait_q);
 264 }
 265
 266 /*
 267  * Function called from device_id.c after sense id has completed.
 268  */
 269 void
 270 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
 271 {
 272         switch (err) {
 273         case 0:
 274                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
 275                 break;
 276         case -ETIME:            /* Sense id stopped by timeout. */
 277                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
 278                 break;
 279         default:
 280                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 281                 break;
 282         }
 283 }
 284
 285 /**
 286   * ccw_device_notify() - inform the device's driver about an event
 287   * @cdev: device for which an event occurred
 288   * @event: event that occurred
 289   *
 290   * Returns:
 291   *   -%EINVAL if the device is offline or has no driver.
 292   *   -%EOPNOTSUPP if the device's driver has no notifier registered.
 293   *   %NOTIFY_OK if the driver wants to keep the device.
 294   *   %NOTIFY_BAD if the driver doesn't want to keep the device.
 295   */
 296 int ccw_device_notify(struct ccw_device *cdev, int event)
 297 {
 298         int ret = -EINVAL;
 299
 300         if (!cdev->drv)
 301                 goto out;
 302         if (!cdev->online)
 303                 goto out;
 304         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
 305                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
 306                       event);
 307         if (!cdev->drv->notify) {
 308                 ret = -EOPNOTSUPP;
 309                 goto out;
 310         }
 311         if (cdev->drv->notify(cdev, event))
 312                 ret = NOTIFY_OK;
 313         else
 314                 ret = NOTIFY_BAD;
 315 out:
 316         return ret;
 317 }
 318
 319 static void ccw_device_oper_notify(struct ccw_device *cdev)
 320 {
 321         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 322
 323         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
 324                 /* Reenable channel measurements, if needed. */
 325                 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
 326                 /* Save indication for new paths. */
 327                 cdev->private->path_new_mask = sch->vpm;
 328                 return;
 329         }
 330         /* Driver doesn't want device back. */
 331         ccw_device_set_notoper(cdev);
 332         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 333 }
 334
 335 /*
 336  * Finished with online/offline processing.
 337  */
 338 static void
 339 ccw_device_done(struct ccw_device *cdev, int state)
 340 {
 341         struct subchannel *sch;
 342
 343         sch = to_subchannel(cdev->dev.parent);
 344
 345         ccw_device_set_timeout(cdev, 0);
 346
 347         if (state != DEV_STATE_ONLINE)
 348                 cio_disable_subchannel(sch);
 349
 350         /* Reset device status. */
 351         memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
 352
 353         cdev->private->state = state;
 354
 355         switch (state) {
 356         case DEV_STATE_BOXED:
 357                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
 358                               cdev->private->dev_id.devno, sch->schid.sch_no);
 359                 if (cdev->online &&
 360                     ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
 361                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 362                 cdev->private->flags.donotify = 0;
 363                 break;
 364         case DEV_STATE_NOT_OPER:
 365                 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
 366                               cdev->private->dev_id.devno, sch->schid.sch_no);
 367                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 368                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 369                 else
 370                         ccw_device_set_disconnected(cdev);
 371                 cdev->private->flags.donotify = 0;
 372                 break;
 373         case DEV_STATE_DISCONNECTED:
 374                 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
 375                               "%04x\n", cdev->private->dev_id.devno,
 376                               sch->schid.sch_no);
 377                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
 378                         cdev->private->state = DEV_STATE_NOT_OPER;
 379                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 380                 } else
 381                         ccw_device_set_disconnected(cdev);
 382                 cdev->private->flags.donotify = 0;
 383                 break;
 384         default:
 385                 break;
 386         }
 387
 388         if (cdev->private->flags.donotify) {
 389                 cdev->private->flags.donotify = 0;
 390                 ccw_device_oper_notify(cdev);
 391         }
 392         wake_up(&cdev->private->wait_q);
 393 }
 394
 395 /*
 396  * Start device recognition.
 397  */
 398 void ccw_device_recognition(struct ccw_device *cdev)
 399 {
 400         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 401
 402         /*
 403          * We used to start here with a sense pgid to find out whether a device
 404          * is locked by someone else. Unfortunately, the sense pgid command
 405          * code has other meanings on devices predating the path grouping
 406          * algorithm, so we start with sense id and box the device after an
 407          * timeout (or if sense pgid during path verification detects the device
 408          * is locked, as may happen on newer devices).
 409          */
 410         cdev->private->flags.recog_done = 0;
 411         cdev->private->state = DEV_STATE_SENSE_ID;
 412         if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
 413                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 414                 return;
 415         }
 416         ccw_device_sense_id_start(cdev);
 417 }
 418
 419 /*
 420  * Handle events for states that use the ccw request infrastructure.
 421  */
 422 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
 423 {
 424         switch (e) {
 425         case DEV_EVENT_NOTOPER:
 426                 ccw_request_notoper(cdev);
 427                 break;
 428         case DEV_EVENT_INTERRUPT:
 429                 ccw_request_handler(cdev);
 430                 break;
 431         case DEV_EVENT_TIMEOUT:
 432                 ccw_request_timeout(cdev);
 433                 break;
 434         default:
 435                 break;
 436         }
 437 }
 438
 439 static void ccw_device_report_path_events(struct ccw_device *cdev)
 440 {
 441         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 442         int path_event[8];
 443         int chp, mask;
 444
 445         for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
 446                 path_event[chp] = PE_NONE;
 447                 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
 448                         path_event[chp] |= PE_PATH_GONE;
 449                 if (mask & cdev->private->path_new_mask & sch->vpm)
 450                         path_event[chp] |= PE_PATH_AVAILABLE;
 451                 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
 452                         path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
 453         }
 454         if (cdev->online && cdev->drv->path_event)
 455                 cdev->drv->path_event(cdev, path_event);
 456 }
 457
 458 static void ccw_device_reset_path_events(struct ccw_device *cdev)
 459 {
 460         cdev->private->path_gone_mask = 0;
 461         cdev->private->path_new_mask = 0;
 462         cdev->private->pgid_reset_mask = 0;
 463 }
 464
 465 static void create_fake_irb(struct irb *irb, int type)
 466 {
 467         memset(irb, 0, sizeof(*irb));
 468         if (type == FAKE_CMD_IRB) {
 469                 struct cmd_scsw *scsw = &irb->scsw.cmd;
 470                 scsw->cc = 1;
 471                 scsw->fctl = SCSW_FCTL_START_FUNC;
 472                 scsw->actl = SCSW_ACTL_START_PEND;
 473                 scsw->stctl = SCSW_STCTL_STATUS_PEND;
 474         } else if (type == FAKE_TM_IRB) {
 475                 struct tm_scsw *scsw = &irb->scsw.tm;
 476                 scsw->x = 1;
 477                 scsw->cc = 1;
 478                 scsw->fctl = SCSW_FCTL_START_FUNC;
 479                 scsw->actl = SCSW_ACTL_START_PEND;
 480                 scsw->stctl = SCSW_STCTL_STATUS_PEND;
 481         }
 482 }
 483
 484 static void ccw_device_handle_broken_paths(struct ccw_device *cdev)
 485 {
 486         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 487         u8 broken_paths = (sch->schib.pmcw.pam & sch->opm) ^ sch->vpm;
 488
 489         if (broken_paths && (cdev->private->path_broken_mask != broken_paths))
 490                 ccw_device_schedule_recovery();
 491
 492         cdev->private->path_broken_mask = broken_paths;
 493 }
 494
 495 void ccw_device_verify_done(struct ccw_device *cdev, int err)
 496 {
 497         struct subchannel *sch;
 498
 499         sch = to_subchannel(cdev->dev.parent);
 500         /* Update schib - pom may have changed. */
 501         if (cio_update_schib(sch)) {
 502                 err = -ENODEV;
 503                 goto callback;
 504         }
 505         /* Update lpm with verified path mask. */
 506         sch->lpm = sch->vpm;
 507         /* Repeat path verification? */
 508         if (cdev->private->flags.doverify) {
 509                 ccw_device_verify_start(cdev);
 510                 return;
 511         }
 512 callback:
 513         switch (err) {
 514         case 0:
 515                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 516                 /* Deliver fake irb to device driver, if needed. */
 517                 if (cdev->private->flags.fake_irb) {
 518                         create_fake_irb(&cdev->private->dma_area->irb,
 519                                         cdev->private->flags.fake_irb);
 520                         cdev->private->flags.fake_irb = 0;
 521                         if (cdev->handler)
 522                                 cdev->handler(cdev, cdev->private->intparm,
 523                                               &cdev->private->dma_area->irb);
 524                         memset(&cdev->private->dma_area->irb, 0,
 525                                sizeof(struct irb));
 526                 }
 527                 ccw_device_report_path_events(cdev);
 528                 ccw_device_handle_broken_paths(cdev);
 529                 break;
 530         case -ETIME:
 531         case -EUSERS:
 532                 /* Reset oper notify indication after verify error. */
 533                 cdev->private->flags.donotify = 0;
 534                 ccw_device_done(cdev, DEV_STATE_BOXED);
 535                 break;
 536         case -EACCES:
 537                 /* Reset oper notify indication after verify error. */
 538                 cdev->private->flags.donotify = 0;
 539                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
 540                 break;
 541         default:
 542                 /* Reset oper notify indication after verify error. */
 543                 cdev->private->flags.donotify = 0;
 544                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 545                 break;
 546         }
 547         ccw_device_reset_path_events(cdev);
 548 }
 549
 550 /*
 551  * Get device online.
 552  */
 553 int
 554 ccw_device_online(struct ccw_device *cdev)
 555 {
 556         struct subchannel *sch;
 557         int ret;
 558
 559         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 560             (cdev->private->state != DEV_STATE_BOXED))
 561                 return -EINVAL;
 562         sch = to_subchannel(cdev->dev.parent);
 563         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
 564         if (ret != 0) {
 565                 /* Couldn't enable the subchannel for i/o. Sick device. */
 566                 if (ret == -ENODEV)
 567                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 568                 return ret;
 569         }
 570         /* Start initial path verification. */
 571         cdev->private->state = DEV_STATE_VERIFY;
 572         ccw_device_verify_start(cdev);
 573         return 0;
 574 }
 575
 576 void
 577 ccw_device_disband_done(struct ccw_device *cdev, int err)
 578 {
 579         switch (err) {
 580         case 0:
 581                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 582                 break;
 583         case -ETIME:
 584                 ccw_device_done(cdev, DEV_STATE_BOXED);
 585                 break;
 586         default:
 587                 cdev->private->flags.donotify = 0;
 588                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 589                 break;
 590         }
 591 }
 592
 593 /*
 594  * Shutdown device.
 595  */
 596 int
 597 ccw_device_offline(struct ccw_device *cdev)
 598 {
 599         struct subchannel *sch;
 600
 601         /* Allow ccw_device_offline while disconnected. */
 602         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
 603             cdev->private->state == DEV_STATE_NOT_OPER) {
 604                 cdev->private->flags.donotify = 0;
 605                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 606                 return 0;
 607         }
 608         if (cdev->private->state == DEV_STATE_BOXED) {
 609                 ccw_device_done(cdev, DEV_STATE_BOXED);
 610                 return 0;
 611         }
 612         if (ccw_device_is_orphan(cdev)) {
 613                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 614                 return 0;
 615         }
 616         sch = to_subchannel(cdev->dev.parent);
 617         if (cio_update_schib(sch))
 618                 return -ENODEV;
 619         if (scsw_actl(&sch->schib.scsw) != 0)
 620                 return -EBUSY;
 621         if (cdev->private->state != DEV_STATE_ONLINE)
 622                 return -EINVAL;
 623         /* Are we doing path grouping? */
 624         if (!cdev->private->flags.pgroup) {
 625                 /* No, set state offline immediately. */
 626                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 627                 return 0;
 628         }
 629         /* Start Set Path Group commands. */
 630         cdev->private->state = DEV_STATE_DISBAND_PGID;
 631         ccw_device_disband_start(cdev);
 632         return 0;
 633 }
 634
 635 /*
 636  * Handle not operational event in non-special state.
 637  */
 638 static void ccw_device_generic_notoper(struct ccw_device *cdev,
 639                                        enum dev_event dev_event)
 640 {
 641         if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 642                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 643         else
 644                 ccw_device_set_disconnected(cdev);
 645 }
 646
 647 /*
 648  * Handle path verification event in offline state.
 649  */
 650 static void ccw_device_offline_verify(struct ccw_device *cdev,
 651                                       enum dev_event dev_event)
 652 {
 653         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 654
 655         css_schedule_eval(sch->schid);
 656 }
 657
 658 /*
 659  * Handle path verification event.
 660  */
 661 static void
 662 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 663 {
 664         struct subchannel *sch;
 665
 666         if (cdev->private->state == DEV_STATE_W4SENSE) {
 667                 cdev->private->flags.doverify = 1;
 668                 return;
 669         }
 670         sch = to_subchannel(cdev->dev.parent);
 671         /*
 672          * Since we might not just be coming from an interrupt from the
 673          * subchannel we have to update the schib.
 674          */
 675         if (cio_update_schib(sch)) {
 676                 ccw_device_verify_done(cdev, -ENODEV);
 677                 return;
 678         }
 679
 680         if (scsw_actl(&sch->schib.scsw) != 0 ||
 681             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
 682             (scsw_stctl(&cdev->private->dma_area->irb.scsw) &
 683              SCSW_STCTL_STATUS_PEND)) {
 684                 /*
 685                  * No final status yet or final status not yet delivered
 686                  * to the device driver. Can't do path verification now,
 687                  * delay until final status was delivered.
 688                  */
 689                 cdev->private->flags.doverify = 1;
 690                 return;
 691         }
 692         /* Device is idle, we can do the path verification. */
 693         cdev->private->state = DEV_STATE_VERIFY;
 694         ccw_device_verify_start(cdev);
 695 }
 696
 697 /*
 698  * Handle path verification event in boxed state.
 699  */
 700 static void ccw_device_boxed_verify(struct ccw_device *cdev,
 701                                     enum dev_event dev_event)
 702 {
 703         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 704
 705         if (cdev->online) {
 706                 if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
 707                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 708                 else
 709                         ccw_device_online_verify(cdev, dev_event);
 710         } else
 711                 css_schedule_eval(sch->schid);
 712 }
 713
 714 /*
 715  * Pass interrupt to device driver.
 716  */
 717 static int ccw_device_call_handler(struct ccw_device *cdev)
 718 {
 719         unsigned int stctl;
 720         int ending_status;
 721
 722         /*
 723          * we allow for the device action handler if .
 724          *  - we received ending status
 725          *  - the action handler requested to see all interrupts
 726          *  - we received an intermediate status
 727          *  - fast notification was requested (primary status)
 728          *  - unsolicited interrupts
 729          */
 730         stctl = scsw_stctl(&cdev->private->dma_area->irb.scsw);
 731         ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
 732                 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
 733                 (stctl == SCSW_STCTL_STATUS_PEND);
 734         if (!ending_status &&
 735             !cdev->private->options.repall &&
 736             !(stctl & SCSW_STCTL_INTER_STATUS) &&
 737             !(cdev->private->options.fast &&
 738               (stctl & SCSW_STCTL_PRIM_STATUS)))
 739                 return 0;
 740
 741         if (ending_status)
 742                 ccw_device_set_timeout(cdev, 0);
 743
 744         if (cdev->handler)
 745                 cdev->handler(cdev, cdev->private->intparm,
 746                               &cdev->private->dma_area->irb);
 747
 748         memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
 749         return 1;
 750 }
 751
 752 /*
 753  * Got an interrupt for a normal io (state online).
 754  */
 755 static void
 756 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 757 {
 758         struct irb *irb;
 759         int is_cmd;
 760
 761         irb = this_cpu_ptr(&cio_irb);
 762         is_cmd = !scsw_is_tm(&irb->scsw);
 763         /* Check for unsolicited interrupt. */
 764         if (!scsw_is_solicited(&irb->scsw)) {
 765                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
 766                     !irb->esw.esw0.erw.cons) {
 767                         /* Unit check but no sense data. Need basic sense. */
 768                         if (ccw_device_do_sense(cdev, irb) != 0)
 769                                 goto call_handler_unsol;
 770                         memcpy(&cdev->private->dma_area->irb, irb,
 771                                sizeof(struct irb));
 772                         cdev->private->state = DEV_STATE_W4SENSE;
 773                         cdev->private->intparm = 0;
 774                         return;
 775                 }
 776 call_handler_unsol:
 777                 if (cdev->handler)
 778                         cdev->handler (cdev, 0, irb);
 779                 if (cdev->private->flags.doverify)
 780                         ccw_device_online_verify(cdev, 0);
 781                 return;
 782         }
 783         /* Accumulate status and find out if a basic sense is needed. */
 784         ccw_device_accumulate_irb(cdev, irb);
 785         if (is_cmd && cdev->private->flags.dosense) {
 786                 if (ccw_device_do_sense(cdev, irb) == 0) {
 787                         cdev->private->state = DEV_STATE_W4SENSE;
 788                 }
 789                 return;
 790         }
 791         /* Call the handler. */
 792         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 793                 /* Start delayed path verification. */
 794                 ccw_device_online_verify(cdev, 0);
 795 }
 796
 797 /*
 798  * Got an timeout in online state.
 799  */
 800 static void
 801 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 802 {
 803         int ret;
 804
 805         ccw_device_set_timeout(cdev, 0);
 806         cdev->private->iretry = 255;
 807         cdev->private->async_kill_io_rc = -ETIMEDOUT;
 808         ret = ccw_device_cancel_halt_clear(cdev);
 809         if (ret == -EBUSY) {
 810                 ccw_device_set_timeout(cdev, 3*HZ);
 811                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 812                 return;
 813         }
 814         if (ret)
 815                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 816         else if (cdev->handler)
 817                 cdev->handler(cdev, cdev->private->intparm,
 818                               ERR_PTR(-ETIMEDOUT));
 819 }
 820
 821 /*
 822  * Got an interrupt for a basic sense.
 823  */
 824 static void
 825 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 826 {
 827         struct irb *irb;
 828
 829         irb = this_cpu_ptr(&cio_irb);
 830         /* Check for unsolicited interrupt. */
 831         if (scsw_stctl(&irb->scsw) ==
 832             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 833                 if (scsw_cc(&irb->scsw) == 1)
 834                         /* Basic sense hasn't started. Try again. */
 835                         ccw_device_do_sense(cdev, irb);
 836                 else {
 837                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
 838                                       "interrupt during w4sense...\n",
 839                                       cdev->private->dev_id.ssid,
 840                                       cdev->private->dev_id.devno);
 841                         if (cdev->handler)
 842                                 cdev->handler (cdev, 0, irb);
 843                 }
 844                 return;
 845         }
 846         /*
 847          * Check if a halt or clear has been issued in the meanwhile. If yes,
 848          * only deliver the halt/clear interrupt to the device driver as if it
 849          * had killed the original request.
 850          */
 851         if (scsw_fctl(&irb->scsw) &
 852             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
 853                 cdev->private->flags.dosense = 0;
 854                 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
 855                 ccw_device_accumulate_irb(cdev, irb);
 856                 goto call_handler;
 857         }
 858         /* Add basic sense info to irb. */
 859         ccw_device_accumulate_basic_sense(cdev, irb);
 860         if (cdev->private->flags.dosense) {
 861                 /* Another basic sense is needed. */
 862                 ccw_device_do_sense(cdev, irb);
 863                 return;
 864         }
 865 call_handler:
 866         cdev->private->state = DEV_STATE_ONLINE;
 867         /* In case sensing interfered with setting the device online */
 868         wake_up(&cdev->private->wait_q);
 869         /* Call the handler. */
 870         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 871                 /* Start delayed path verification. */
 872                 ccw_device_online_verify(cdev, 0);
 873 }
 874
 875 static void
 876 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 877 {
 878         ccw_device_set_timeout(cdev, 0);
 879         /* Start delayed path verification. */
 880         ccw_device_online_verify(cdev, 0);
 881         /* OK, i/o is dead now. Call interrupt handler. */
 882         if (cdev->handler)
 883                 cdev->handler(cdev, cdev->private->intparm,
 884                               ERR_PTR(cdev->private->async_kill_io_rc));
 885 }
 886
 887 static void
 888 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 889 {
 890         int ret;
 891
 892         ret = ccw_device_cancel_halt_clear(cdev);
 893         if (ret == -EBUSY) {
 894                 ccw_device_set_timeout(cdev, 3*HZ);
 895                 return;
 896         }
 897         /* Start delayed path verification. */
 898         ccw_device_online_verify(cdev, 0);
 899         if (cdev->handler)
 900                 cdev->handler(cdev, cdev->private->intparm,
 901                               ERR_PTR(cdev->private->async_kill_io_rc));
 902 }
 903
 904 void ccw_device_kill_io(struct ccw_device *cdev)
 905 {
 906         int ret;
 907
 908         ccw_device_set_timeout(cdev, 0);
 909         cdev->private->iretry = 255;
 910         cdev->private->async_kill_io_rc = -EIO;
 911         ret = ccw_device_cancel_halt_clear(cdev);
 912         if (ret == -EBUSY) {
 913                 ccw_device_set_timeout(cdev, 3*HZ);
 914                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 915                 return;
 916         }
 917         /* Start delayed path verification. */
 918         ccw_device_online_verify(cdev, 0);
 919         if (cdev->handler)
 920                 cdev->handler(cdev, cdev->private->intparm,
 921                               ERR_PTR(-EIO));
 922 }
 923
 924 static void
 925 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 926 {
 927         /* Start verification after current task finished. */
 928         cdev->private->flags.doverify = 1;
 929 }
 930
 931 static void
 932 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 933 {
 934         struct subchannel *sch;
 935
 936         sch = to_subchannel(cdev->dev.parent);
 937         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
 938                 /* Couldn't enable the subchannel for i/o. Sick device. */
 939                 return;
 940         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 941         ccw_device_sense_id_start(cdev);
 942 }
 943
 944 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
 945 {
 946         struct subchannel *sch;
 947
 948         if (cdev->private->state != DEV_STATE_DISCONNECTED)
 949                 return;
 950
 951         sch = to_subchannel(cdev->dev.parent);
 952         /* Update some values. */
 953         if (cio_update_schib(sch))
 954                 return;
 955         /*
 956          * The pim, pam, pom values may not be accurate, but they are the best
 957          * we have before performing device selection :/
 958          */
 959         sch->lpm = sch->schib.pmcw.pam & sch->opm;
 960         /*
 961          * Use the initial configuration since we can't be shure that the old
 962          * paths are valid.
 963          */
 964         io_subchannel_init_config(sch);
 965         if (cio_commit_config(sch))
 966                 return;
 967
 968         /* We should also udate ssd info, but this has to wait. */
 969         /* Check if this is another device which appeared on the same sch. */
 970         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
 971                 css_schedule_eval(sch->schid);
 972         else
 973                 ccw_device_start_id(cdev, 0);
 974 }
 975
 976 static void ccw_device_disabled_irq(struct ccw_device *cdev,
 977                                     enum dev_event dev_event)
 978 {
 979         struct subchannel *sch;
 980
 981         sch = to_subchannel(cdev->dev.parent);
 982         /*
 983          * An interrupt in a disabled state means a previous disable was not
 984          * successful - should not happen, but we try to disable again.
 985          */
 986         cio_disable_subchannel(sch);
 987 }
 988
 989 static void
 990 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
 991 {
 992         retry_set_schib(cdev);
 993         cdev->private->state = DEV_STATE_ONLINE;
 994         dev_fsm_event(cdev, dev_event);
 995 }
 996
 997 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
 998                                        enum dev_event dev_event)
 999 {
1000         cmf_retry_copy_block(cdev);
1001         cdev->private->state = DEV_STATE_ONLINE;
1002         dev_fsm_event(cdev, dev_event);
1003 }
1004
1005 static void
1006 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
1007 {
1008         ccw_device_set_timeout(cdev, 0);
1009         cdev->private->state = DEV_STATE_NOT_OPER;
1010         wake_up(&cdev->private->wait_q);
1011 }
1012
1013 static void
1014 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
1015 {
1016         int ret;
1017
1018         ret = ccw_device_cancel_halt_clear(cdev);
1019         if (ret == -EBUSY) {
1020                 ccw_device_set_timeout(cdev, HZ/10);
1021         } else {
1022                 cdev->private->state = DEV_STATE_NOT_OPER;
1023                 wake_up(&cdev->private->wait_q);
1024         }
1025 }
1026
1027 /*
1028  * No operation action. This is used e.g. to ignore a timeout event in
1029  * state offline.
1030  */
1031 static void
1032 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1033 {
1034 }
1035
1036 /*
1037  * device statemachine
1038  */
1039 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1040         [DEV_STATE_NOT_OPER] = {
1041                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1042                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1043                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1044                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1045         },
1046         [DEV_STATE_SENSE_ID] = {
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_OFFLINE] = {
1053                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1054                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1055                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1056                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
1057         },
1058         [DEV_STATE_VERIFY] = {
1059                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1060                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1061                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1062                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
1063         },
1064         [DEV_STATE_ONLINE] = {
1065                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1066                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1067                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1068                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1069         },
1070         [DEV_STATE_W4SENSE] = {
1071                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1072                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1073                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1074                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1075         },
1076         [DEV_STATE_DISBAND_PGID] = {
1077                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1078                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1079                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1080                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1081         },
1082         [DEV_STATE_BOXED] = {
1083                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1084                 [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
1085                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1086                 [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
1087         },
1088         /* states to wait for i/o completion before doing something */
1089         [DEV_STATE_TIMEOUT_KILL] = {
1090                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1091                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1092                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1093                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1094         },
1095         [DEV_STATE_QUIESCE] = {
1096                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1097                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1098                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1099                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1100         },
1101         /* special states for devices gone not operational */
1102         [DEV_STATE_DISCONNECTED] = {
1103                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1104                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1105                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1106                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1107         },
1108         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1109                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1110                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1111                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1112                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1113         },
1114         [DEV_STATE_CMFCHANGE] = {
1115                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1116                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1117                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1118                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1119         },
1120         [DEV_STATE_CMFUPDATE] = {
1121                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1122                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1123                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1124                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1125         },
1126         [DEV_STATE_STEAL_LOCK] = {
1127                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1128                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1129                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1130                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1131         },
1132 };
1133
1134 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);