drivers/s390/cio/device_fsm.c

   1 /*
   2  * drivers/s390/cio/device_fsm.c
   3  * finite state machine for device handling
   4  *
   5  *    Copyright (C) 2002 IBM Deutschland Entwicklung GmbH,
   6  *                       IBM Corporation
   7  *    Author(s): Cornelia Huck(cohuck@de.ibm.com)
   8  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/config.h>
  13 #include <linux/init.h>
  14
  15 #include <asm/ccwdev.h>
  16 #include <asm/qdio.h>
  17
  18 #include "cio.h"
  19 #include "cio_debug.h"
  20 #include "css.h"
  21 #include "device.h"
  22 #include "chsc.h"
  23 #include "ioasm.h"
  24 #include "qdio.h"
  25
  26 int
  27 device_is_disconnected(struct subchannel *sch)
  28 {
  29         struct ccw_device *cdev;
  30
  31         if (!sch->dev.driver_data)
  32                 return 0;
  33         cdev = sch->dev.driver_data;
  34         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
  35                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
  36 }
  37
  38 void
  39 device_set_disconnected(struct subchannel *sch)
  40 {
  41         struct ccw_device *cdev;
  42
  43         if (!sch->dev.driver_data)
  44                 return;
  45         cdev = sch->dev.driver_data;
  46         ccw_device_set_timeout(cdev, 0);
  47         cdev->private->state = DEV_STATE_DISCONNECTED;
  48 }
  49
  50 void
  51 device_set_waiting(struct subchannel *sch)
  52 {
  53         struct ccw_device *cdev;
  54
  55         if (!sch->dev.driver_data)
  56                 return;
  57         cdev = sch->dev.driver_data;
  58         ccw_device_set_timeout(cdev, 10*HZ);
  59         cdev->private->state = DEV_STATE_WAIT4IO;
  60 }
  61
  62 /*
  63  * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
  64  */
  65 static void
  66 ccw_device_timeout(unsigned long data)
  67 {
  68         struct ccw_device *cdev;
  69
  70         cdev = (struct ccw_device *) data;
  71         spin_lock_irq(cdev->ccwlock);
  72         dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
  73         spin_unlock_irq(cdev->ccwlock);
  74 }
  75
  76 /*
  77  * Set timeout
  78  */
  79 void
  80 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
  81 {
  82         if (expires == 0) {
  83                 del_timer(&cdev->private->timer);
  84                 return;
  85         }
  86         if (timer_pending(&cdev->private->timer)) {
  87                 if (mod_timer(&cdev->private->timer, jiffies + expires))
  88                         return;
  89         }
  90         cdev->private->timer.function = ccw_device_timeout;
  91         cdev->private->timer.data = (unsigned long) cdev;
  92         cdev->private->timer.expires = jiffies + expires;
  93         add_timer(&cdev->private->timer);
  94 }
  95
  96 /* Kill any pending timers after machine check. */
  97 void
  98 device_kill_pending_timer(struct subchannel *sch)
  99 {
 100         struct ccw_device *cdev;
 101
 102         if (!sch->dev.driver_data)
 103                 return;
 104         cdev = sch->dev.driver_data;
 105         ccw_device_set_timeout(cdev, 0);
 106 }
 107
 108 /*
 109  * Cancel running i/o. This is called repeatedly since halt/clear are
 110  * asynchronous operations. We do one try with cio_cancel, two tries
 111  * with cio_halt, 255 tries with cio_clear. If everythings fails panic.
 112  * Returns 0 if device now idle, -ENODEV for device not operational and
 113  * -EBUSY if an interrupt is expected (either from halt/clear or from a
 114  * status pending).
 115  */
 116 int
 117 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
 118 {
 119         struct subchannel *sch;
 120         int ret;
 121
 122         sch = to_subchannel(cdev->dev.parent);
 123         ret = stsch(sch->irq, &sch->schib);
 124         if (ret || !sch->schib.pmcw.dnv)
 125                 return -ENODEV;
 126         if (!sch->schib.pmcw.ena || sch->schib.scsw.actl == 0)
 127                 /* Not operational or no activity -> done. */
 128                 return 0;
 129         /* Stage 1: cancel io. */
 130         if (!(sch->schib.scsw.actl & SCSW_ACTL_HALT_PEND) &&
 131             !(sch->schib.scsw.actl & SCSW_ACTL_CLEAR_PEND)) {
 132                 ret = cio_cancel(sch);
 133                 if (ret != -EINVAL)
 134                         return ret;
 135                 /* cancel io unsuccessful. From now on it is asynchronous. */
 136                 cdev->private->iretry = 3;      /* 3 halt retries. */
 137         }
 138         if (!(sch->schib.scsw.actl & SCSW_ACTL_CLEAR_PEND)) {
 139                 /* Stage 2: halt io. */
 140                 if (cdev->private->iretry) {
 141                         cdev->private->iretry--;
 142                         ret = cio_halt(sch);
 143                         return (ret == 0) ? -EBUSY : ret;
 144                 }
 145                 /* halt io unsuccessful. */
 146                 cdev->private->iretry = 255;    /* 255 clear retries. */
 147         }
 148         /* Stage 3: clear io. */
 149         if (cdev->private->iretry) {
 150                 cdev->private->iretry--;
 151                 ret = cio_clear (sch);
 152                 return (ret == 0) ? -EBUSY : ret;
 153         }
 154         panic("Can't stop i/o on subchannel.\n");
 155 }
 156
 157 static int
 158 ccw_device_handle_oper(struct ccw_device *cdev)
 159 {
 160         struct subchannel *sch;
 161
 162         sch = to_subchannel(cdev->dev.parent);
 163         cdev->private->flags.recog_done = 1;
 164         /*
 165          * Check if cu type and device type still match. If
 166          * not, it is certainly another device and we have to
 167          * de- and re-register. Also check here for non-matching devno.
 168          */
 169         if (cdev->id.cu_type != cdev->private->senseid.cu_type ||
 170             cdev->id.cu_model != cdev->private->senseid.cu_model ||
 171             cdev->id.dev_type != cdev->private->senseid.dev_type ||
 172             cdev->id.dev_model != cdev->private->senseid.dev_model ||
 173             cdev->private->devno != sch->schib.pmcw.dev) {
 174                 PREPARE_WORK(&cdev->private->kick_work,
 175                              ccw_device_do_unreg_rereg, (void *)cdev);
 176                 queue_work(ccw_device_work, &cdev->private->kick_work);
 177                 return 0;
 178         }
 179         cdev->private->flags.donotify = 1;
 180         return 1;
 181 }
 182
 183 /*
 184  * The machine won't give us any notification by machine check if a chpid has
 185  * been varied online on the SE so we have to find out by magic (i. e. driving
 186  * the channel subsystem to device selection and updating our path masks).
 187  */
 188 static inline void
 189 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
 190 {
 191         int mask, i;
 192
 193         for (i = 0; i<8; i++) {
 194                 mask = 0x80 >> i;
 195                 if (!(sch->lpm & mask))
 196                         continue;
 197                 if (old_lpm & mask)
 198                         continue;
 199                 chpid_is_actually_online(sch->schib.pmcw.chpid[i]);
 200         }
 201 }
 202
 203 /*
 204  * Stop device recognition.
 205  */
 206 static void
 207 ccw_device_recog_done(struct ccw_device *cdev, int state)
 208 {
 209         struct subchannel *sch;
 210         int notify, old_lpm, same_dev;
 211
 212         sch = to_subchannel(cdev->dev.parent);
 213
 214         ccw_device_set_timeout(cdev, 0);
 215         cio_disable_subchannel(sch);
 216         /*
 217          * Now that we tried recognition, we have performed device selection
 218          * through ssch() and the path information is up to date.
 219          */
 220         old_lpm = sch->lpm;
 221         stsch(sch->irq, &sch->schib);
 222         sch->lpm = sch->schib.pmcw.pim &
 223                 sch->schib.pmcw.pam &
 224                 sch->schib.pmcw.pom &
 225                 sch->opm;
 226         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
 227                 /* Force reprobe on all chpids. */
 228                 old_lpm = 0;
 229         if (sch->lpm != old_lpm)
 230                 __recover_lost_chpids(sch, old_lpm);
 231         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) {
 232                 if (state == DEV_STATE_NOT_OPER) {
 233                         cdev->private->flags.recog_done = 1;
 234                         cdev->private->state = DEV_STATE_DISCONNECTED;
 235                         return;
 236                 }
 237                 /* Boxed devices don't need extra treatment. */
 238         }
 239         notify = 0;
 240         same_dev = 0; /* Keep the compiler quiet... */
 241         switch (state) {
 242         case DEV_STATE_NOT_OPER:
 243                 CIO_DEBUG(KERN_WARNING, 2,
 244                           "SenseID : unknown device %04x on subchannel %04x\n",
 245                           cdev->private->devno, sch->irq);
 246                 break;
 247         case DEV_STATE_OFFLINE:
 248                 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) {
 249                         same_dev = ccw_device_handle_oper(cdev);
 250                         notify = 1;
 251                 }
 252                 /* fill out sense information */
 253                 cdev->id = (struct ccw_device_id) {
 254                         .cu_type   = cdev->private->senseid.cu_type,
 255                         .cu_model  = cdev->private->senseid.cu_model,
 256                         .dev_type  = cdev->private->senseid.dev_type,
 257                         .dev_model = cdev->private->senseid.dev_model,
 258                 };
 259                 if (notify) {
 260                         cdev->private->state = DEV_STATE_OFFLINE;
 261                         if (same_dev) {
 262                                 /* Get device online again. */
 263                                 ccw_device_online(cdev);
 264                                 wake_up(&cdev->private->wait_q);
 265                         }
 266                         return;
 267                 }
 268                 /* Issue device info message. */
 269                 CIO_DEBUG(KERN_INFO, 2, "SenseID : device %04x reports: "
 270                           "CU  Type/Mod = %04X/%02X, Dev Type/Mod = "
 271                           "%04X/%02X\n", cdev->private->devno,
 272                           cdev->id.cu_type, cdev->id.cu_model,
 273                           cdev->id.dev_type, cdev->id.dev_model);
 274                 break;
 275         case DEV_STATE_BOXED:
 276                 CIO_DEBUG(KERN_WARNING, 2,
 277                           "SenseID : boxed device %04x on subchannel %04x\n",
 278                           cdev->private->devno, sch->irq);
 279                 break;
 280         }
 281         cdev->private->state = state;
 282         io_subchannel_recog_done(cdev);
 283         if (state != DEV_STATE_NOT_OPER)
 284                 wake_up(&cdev->private->wait_q);
 285 }
 286
 287 /*
 288  * Function called from device_id.c after sense id has completed.
 289  */
 290 void
 291 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
 292 {
 293         switch (err) {
 294         case 0:
 295                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
 296                 break;
 297         case -ETIME:            /* Sense id stopped by timeout. */
 298                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
 299                 break;
 300         default:
 301                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 302                 break;
 303         }
 304 }
 305
 306 static void
 307 ccw_device_oper_notify(void *data)
 308 {
 309         struct ccw_device *cdev;
 310         struct subchannel *sch;
 311         int ret;
 312
 313         cdev = (struct ccw_device *)data;
 314         sch = to_subchannel(cdev->dev.parent);
 315         ret = (sch->driver && sch->driver->notify) ?
 316                 sch->driver->notify(&sch->dev, CIO_OPER) : 0;
 317         if (!ret)
 318                 /* Driver doesn't want device back. */
 319                 ccw_device_do_unreg_rereg((void *)cdev);
 320         else
 321                 wake_up(&cdev->private->wait_q);
 322 }
 323
 324 /*
 325  * Finished with online/offline processing.
 326  */
 327 static void
 328 ccw_device_done(struct ccw_device *cdev, int state)
 329 {
 330         struct subchannel *sch;
 331
 332         sch = to_subchannel(cdev->dev.parent);
 333
 334         if (state != DEV_STATE_ONLINE)
 335                 cio_disable_subchannel(sch);
 336
 337         /* Reset device status. */
 338         memset(&cdev->private->irb, 0, sizeof(struct irb));
 339
 340         cdev->private->state = state;
 341
 342
 343         if (state == DEV_STATE_BOXED)
 344                 CIO_DEBUG(KERN_WARNING, 2,
 345                           "Boxed device %04x on subchannel %04x\n",
 346                           cdev->private->devno, sch->irq);
 347
 348         if (cdev->private->flags.donotify) {
 349                 cdev->private->flags.donotify = 0;
 350                 PREPARE_WORK(&cdev->private->kick_work, ccw_device_oper_notify,
 351                              (void *)cdev);
 352                 queue_work(ccw_device_notify_work, &cdev->private->kick_work);
 353         }
 354         wake_up(&cdev->private->wait_q);
 355
 356         if (css_init_done && state != DEV_STATE_ONLINE)
 357                 put_device (&cdev->dev);
 358 }
 359
 360 /*
 361  * Function called from device_pgid.c after sense path ground has completed.
 362  */
 363 void
 364 ccw_device_sense_pgid_done(struct ccw_device *cdev, int err)
 365 {
 366         struct subchannel *sch;
 367
 368         sch = to_subchannel(cdev->dev.parent);
 369         switch (err) {
 370         case 0:
 371                 /* Start Path Group verification. */
 372                 sch->vpm = 0;   /* Start with no path groups set. */
 373                 cdev->private->state = DEV_STATE_VERIFY;
 374                 ccw_device_verify_start(cdev);
 375                 break;
 376         case -ETIME:            /* Sense path group id stopped by timeout. */
 377         case -EUSERS:           /* device is reserved for someone else. */
 378                 ccw_device_done(cdev, DEV_STATE_BOXED);
 379                 break;
 380         case -EOPNOTSUPP: /* path grouping not supported, just set online. */
 381                 cdev->private->options.pgroup = 0;
 382                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 383                 break;
 384         default:
 385                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 386                 break;
 387         }
 388 }
 389
 390 /*
 391  * Start device recognition.
 392  */
 393 int
 394 ccw_device_recognition(struct ccw_device *cdev)
 395 {
 396         struct subchannel *sch;
 397         int ret;
 398
 399         if ((cdev->private->state != DEV_STATE_NOT_OPER) &&
 400             (cdev->private->state != DEV_STATE_BOXED))
 401                 return -EINVAL;
 402         sch = to_subchannel(cdev->dev.parent);
 403         ret = cio_enable_subchannel(sch, sch->schib.pmcw.isc);
 404         if (ret != 0)
 405                 /* Couldn't enable the subchannel for i/o. Sick device. */
 406                 return ret;
 407
 408         /* After 60s the device recognition is considered to have failed. */
 409         ccw_device_set_timeout(cdev, 60*HZ);
 410
 411         /*
 412          * We used to start here with a sense pgid to find out whether a device
 413          * is locked by someone else. Unfortunately, the sense pgid command
 414          * code has other meanings on devices predating the path grouping
 415          * algorithm, so we start with sense id and box the device after an
 416          * timeout (or if sense pgid during path verification detects the device
 417          * is locked, as may happen on newer devices).
 418          */
 419         cdev->private->flags.recog_done = 0;
 420         cdev->private->state = DEV_STATE_SENSE_ID;
 421         ccw_device_sense_id_start(cdev);
 422         return 0;
 423 }
 424
 425 /*
 426  * Handle timeout in device recognition.
 427  */
 428 static void
 429 ccw_device_recog_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 430 {
 431         int ret;
 432
 433         ret = ccw_device_cancel_halt_clear(cdev);
 434         switch (ret) {
 435         case 0:
 436                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
 437                 break;
 438         case -ENODEV:
 439                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 440                 break;
 441         default:
 442                 ccw_device_set_timeout(cdev, 3*HZ);
 443         }
 444 }
 445
 446
 447 static void
 448 ccw_device_nopath_notify(void *data)
 449 {
 450         struct ccw_device *cdev;
 451         struct subchannel *sch;
 452         int ret;
 453
 454         cdev = (struct ccw_device *)data;
 455         sch = to_subchannel(cdev->dev.parent);
 456         /* Extra sanity. */
 457         if (sch->lpm)
 458                 return;
 459         ret = (sch->driver && sch->driver->notify) ?
 460                 sch->driver->notify(&sch->dev, CIO_NO_PATH) : 0;
 461         if (!ret) {
 462                 if (get_device(&sch->dev)) {
 463                         /* Driver doesn't want to keep device. */
 464                         cio_disable_subchannel(sch);
 465                         if (get_device(&cdev->dev)) {
 466                                 PREPARE_WORK(&cdev->private->kick_work,
 467                                              ccw_device_call_sch_unregister,
 468                                              (void *)cdev);
 469                                 queue_work(ccw_device_work,
 470                                            &cdev->private->kick_work);
 471                         } else
 472                                 put_device(&sch->dev);
 473                 }
 474         } else {
 475                 cio_disable_subchannel(sch);
 476                 ccw_device_set_timeout(cdev, 0);
 477                 cdev->private->state = DEV_STATE_DISCONNECTED;
 478                 wake_up(&cdev->private->wait_q);
 479         }
 480 }
 481
 482 void
 483 ccw_device_verify_done(struct ccw_device *cdev, int err)
 484 {
 485         cdev->private->flags.doverify = 0;
 486         switch (err) {
 487         case -EOPNOTSUPP: /* path grouping not supported, just set online. */
 488                 cdev->private->options.pgroup = 0;
 489         case 0:
 490                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 491                 break;
 492         case -ETIME:
 493                 ccw_device_done(cdev, DEV_STATE_BOXED);
 494                 break;
 495         default:
 496                 PREPARE_WORK(&cdev->private->kick_work,
 497                              ccw_device_nopath_notify, (void *)cdev);
 498                 queue_work(ccw_device_notify_work, &cdev->private->kick_work);
 499                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 500                 break;
 501         }
 502 }
 503
 504 /*
 505  * Get device online.
 506  */
 507 int
 508 ccw_device_online(struct ccw_device *cdev)
 509 {
 510         struct subchannel *sch;
 511         int ret;
 512
 513         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 514             (cdev->private->state != DEV_STATE_BOXED))
 515                 return -EINVAL;
 516         sch = to_subchannel(cdev->dev.parent);
 517         if (css_init_done && !get_device(&cdev->dev))
 518                 return -ENODEV;
 519         ret = cio_enable_subchannel(sch, sch->schib.pmcw.isc);
 520         if (ret != 0) {
 521                 /* Couldn't enable the subchannel for i/o. Sick device. */
 522                 if (ret == -ENODEV)
 523                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 524                 return ret;
 525         }
 526         /* Do we want to do path grouping? */
 527         if (!cdev->private->options.pgroup) {
 528                 /* No, set state online immediately. */
 529                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 530                 return 0;
 531         }
 532         /* Do a SensePGID first. */
 533         cdev->private->state = DEV_STATE_SENSE_PGID;
 534         ccw_device_sense_pgid_start(cdev);
 535         return 0;
 536 }
 537
 538 void
 539 ccw_device_disband_done(struct ccw_device *cdev, int err)
 540 {
 541         switch (err) {
 542         case 0:
 543                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 544                 break;
 545         case -ETIME:
 546                 ccw_device_done(cdev, DEV_STATE_BOXED);
 547                 break;
 548         default:
 549                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 550                 break;
 551         }
 552 }
 553
 554 /*
 555  * Shutdown device.
 556  */
 557 int
 558 ccw_device_offline(struct ccw_device *cdev)
 559 {
 560         struct subchannel *sch;
 561
 562         sch = to_subchannel(cdev->dev.parent);
 563         if (cdev->private->state != DEV_STATE_ONLINE) {
 564                 if (sch->schib.scsw.actl != 0)
 565                         return -EBUSY;
 566                 return -EINVAL;
 567         }
 568         if (sch->schib.scsw.actl != 0)
 569                 return -EBUSY;
 570         /* Are we doing path grouping? */
 571         if (!cdev->private->options.pgroup) {
 572                 /* No, set state offline immediately. */
 573                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 574                 return 0;
 575         }
 576         /* Start Set Path Group commands. */
 577         cdev->private->state = DEV_STATE_DISBAND_PGID;
 578         ccw_device_disband_start(cdev);
 579         return 0;
 580 }
 581
 582 /*
 583  * Handle timeout in device online/offline process.
 584  */
 585 static void
 586 ccw_device_onoff_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 587 {
 588         int ret;
 589
 590         ret = ccw_device_cancel_halt_clear(cdev);
 591         switch (ret) {
 592         case 0:
 593                 ccw_device_done(cdev, DEV_STATE_BOXED);
 594                 break;
 595         case -ENODEV:
 596                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 597                 break;
 598         default:
 599                 ccw_device_set_timeout(cdev, 3*HZ);
 600         }
 601 }
 602
 603 /*
 604  * Handle not oper event in device recognition.
 605  */
 606 static void
 607 ccw_device_recog_notoper(struct ccw_device *cdev, enum dev_event dev_event)
 608 {
 609         ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 610 }
 611
 612 /*
 613  * Handle not operational event while offline.
 614  */
 615 static void
 616 ccw_device_offline_notoper(struct ccw_device *cdev, enum dev_event dev_event)
 617 {
 618         struct subchannel *sch;
 619
 620         cdev->private->state = DEV_STATE_NOT_OPER;
 621         sch = to_subchannel(cdev->dev.parent);
 622         device_unregister(&sch->dev);
 623         sch->schib.pmcw.intparm = 0;
 624         cio_modify(sch);
 625         wake_up(&cdev->private->wait_q);
 626 }
 627
 628 /*
 629  * Handle not operational event while online.
 630  */
 631 static void
 632 ccw_device_online_notoper(struct ccw_device *cdev, enum dev_event dev_event)
 633 {
 634         struct subchannel *sch;
 635
 636         sch = to_subchannel(cdev->dev.parent);
 637         if (sch->driver->notify &&
 638             sch->driver->notify(&sch->dev, sch->lpm ? CIO_GONE : CIO_NO_PATH)) {
 639                         ccw_device_set_timeout(cdev, 0);
 640                         cdev->private->state = DEV_STATE_DISCONNECTED;
 641                         wake_up(&cdev->private->wait_q);
 642                         return;
 643         }
 644         cdev->private->state = DEV_STATE_NOT_OPER;
 645         cio_disable_subchannel(sch);
 646         if (sch->schib.scsw.actl != 0) {
 647                 // FIXME: not-oper indication to device driver ?
 648                 ccw_device_call_handler(cdev);
 649         }
 650         device_unregister(&sch->dev);
 651         sch->schib.pmcw.intparm = 0;
 652         cio_modify(sch);
 653         wake_up(&cdev->private->wait_q);
 654 }
 655
 656 /*
 657  * Handle path verification event.
 658  */
 659 static void
 660 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 661 {
 662         struct subchannel *sch;
 663
 664         if (!cdev->private->options.pgroup)
 665                 return;
 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         if (sch->schib.scsw.actl != 0 ||
 672             (cdev->private->irb.scsw.stctl & SCSW_STCTL_STATUS_PEND)) {
 673                 /*
 674                  * No final status yet or final status not yet delivered
 675                  * to the device driver. Can't do path verfication now,
 676                  * delay until final status was delivered.
 677                  */
 678                 cdev->private->flags.doverify = 1;
 679                 return;
 680         }
 681         /* Device is idle, we can do the path verification. */
 682         cdev->private->state = DEV_STATE_VERIFY;
 683         ccw_device_verify_start(cdev);
 684 }
 685
 686 /*
 687  * Got an interrupt for a normal io (state online).
 688  */
 689 static void
 690 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 691 {
 692         struct irb *irb;
 693
 694         irb = (struct irb *) __LC_IRB;
 695         /* Check for unsolicited interrupt. */
 696         if ((irb->scsw.stctl ==
 697                         (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS))
 698             && (!irb->scsw.cc)) {
 699                 if ((irb->scsw.dstat & DEV_STAT_UNIT_CHECK) &&
 700                     !irb->esw.esw0.erw.cons) {
 701                         /* Unit check but no sense data. Need basic sense. */
 702                         if (ccw_device_do_sense(cdev, irb) != 0)
 703                                 goto call_handler_unsol;
 704                         memcpy(irb, &cdev->private->irb, sizeof(struct irb));
 705                         cdev->private->state = DEV_STATE_W4SENSE;
 706                         cdev->private->intparm = 0;
 707                         return;
 708                 }
 709 call_handler_unsol:
 710                 if (cdev->handler)
 711                         cdev->handler (cdev, 0, irb);
 712                 return;
 713         }
 714         /* Accumulate status and find out if a basic sense is needed. */
 715         ccw_device_accumulate_irb(cdev, irb);
 716         if (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                 struct subchannel *sch;
 745
 746                 sch = to_subchannel(cdev->dev.parent);
 747                 if (!sch->lpm) {
 748                         PREPARE_WORK(&cdev->private->kick_work,
 749                                      ccw_device_nopath_notify, (void *)cdev);
 750                         queue_work(ccw_device_notify_work,
 751                                    &cdev->private->kick_work);
 752                 } else
 753                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 754         } else if (cdev->handler)
 755                 cdev->handler(cdev, cdev->private->intparm,
 756                               ERR_PTR(-ETIMEDOUT));
 757 }
 758
 759 /*
 760  * Got an interrupt for a basic sense.
 761  */
 762 void
 763 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 764 {
 765         struct irb *irb;
 766
 767         irb = (struct irb *) __LC_IRB;
 768         /* Check for unsolicited interrupt. */
 769         if (irb->scsw.stctl ==
 770                         (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 771                 if (irb->scsw.cc == 1)
 772                         /* Basic sense hasn't started. Try again. */
 773                         ccw_device_do_sense(cdev, irb);
 774                 else {
 775                         printk("Huh? %s(%s): unsolicited interrupt...\n",
 776                                __FUNCTION__, cdev->dev.bus_id);
 777                         if (cdev->handler)
 778                                 cdev->handler (cdev, 0, irb);
 779                 }
 780                 return;
 781         }
 782         /* Add basic sense info to irb. */
 783         ccw_device_accumulate_basic_sense(cdev, irb);
 784         if (cdev->private->flags.dosense) {
 785                 /* Another basic sense is needed. */
 786                 ccw_device_do_sense(cdev, irb);
 787                 return;
 788         }
 789         cdev->private->state = DEV_STATE_ONLINE;
 790         /* Call the handler. */
 791         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 792                 /* Start delayed path verification. */
 793                 ccw_device_online_verify(cdev, 0);
 794 }
 795
 796 static void
 797 ccw_device_clear_verify(struct ccw_device *cdev, enum dev_event dev_event)
 798 {
 799         struct irb *irb;
 800
 801         irb = (struct irb *) __LC_IRB;
 802         /* Accumulate status. We don't do basic sense. */
 803         ccw_device_accumulate_irb(cdev, irb);
 804         /* Try to start delayed device verification. */
 805         ccw_device_online_verify(cdev, 0);
 806         /* Note: Don't call handler for cio initiated clear! */
 807 }
 808
 809 static void
 810 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 811 {
 812         struct subchannel *sch;
 813
 814         sch = to_subchannel(cdev->dev.parent);
 815         ccw_device_set_timeout(cdev, 0);
 816         /* OK, i/o is dead now. Call interrupt handler. */
 817         cdev->private->state = DEV_STATE_ONLINE;
 818         if (cdev->handler)
 819                 cdev->handler(cdev, cdev->private->intparm,
 820                               ERR_PTR(-ETIMEDOUT));
 821         if (!sch->lpm) {
 822                 PREPARE_WORK(&cdev->private->kick_work,
 823                              ccw_device_nopath_notify, (void *)cdev);
 824                 queue_work(ccw_device_notify_work, &cdev->private->kick_work);
 825         } else if (cdev->private->flags.doverify)
 826                 /* Start delayed path verification. */
 827                 ccw_device_online_verify(cdev, 0);
 828 }
 829
 830 static void
 831 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 832 {
 833         int ret;
 834
 835         ret = ccw_device_cancel_halt_clear(cdev);
 836         if (ret == -EBUSY) {
 837                 ccw_device_set_timeout(cdev, 3*HZ);
 838                 return;
 839         }
 840         if (ret == -ENODEV) {
 841                 struct subchannel *sch;
 842
 843                 sch = to_subchannel(cdev->dev.parent);
 844                 if (!sch->lpm) {
 845                         PREPARE_WORK(&cdev->private->kick_work,
 846                                      ccw_device_nopath_notify, (void *)cdev);
 847                         queue_work(ccw_device_notify_work,
 848                                    &cdev->private->kick_work);
 849                 } else
 850                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 851                 return;
 852         }
 853         //FIXME: Can we get here?
 854         cdev->private->state = DEV_STATE_ONLINE;
 855         if (cdev->handler)
 856                 cdev->handler(cdev, cdev->private->intparm,
 857                               ERR_PTR(-ETIMEDOUT));
 858 }
 859
 860 static void
 861 ccw_device_wait4io_irq(struct ccw_device *cdev, enum dev_event dev_event)
 862 {
 863         struct irb *irb;
 864         struct subchannel *sch;
 865
 866         irb = (struct irb *) __LC_IRB;
 867         /*
 868          * Accumulate status and find out if a basic sense is needed.
 869          * This is fine since we have already adapted the lpm.
 870          */
 871         ccw_device_accumulate_irb(cdev, irb);
 872         if (cdev->private->flags.dosense) {
 873                 if (ccw_device_do_sense(cdev, irb) == 0) {
 874                         cdev->private->state = DEV_STATE_W4SENSE;
 875                 }
 876                 return;
 877         }
 878
 879         /* Iff device is idle, reset timeout. */
 880         sch = to_subchannel(cdev->dev.parent);
 881         if (!stsch(sch->irq, &sch->schib))
 882                 if (sch->schib.scsw.actl == 0)
 883                         ccw_device_set_timeout(cdev, 0);
 884         /* Call the handler. */
 885         ccw_device_call_handler(cdev);
 886         if (!sch->lpm) {
 887                 PREPARE_WORK(&cdev->private->kick_work,
 888                              ccw_device_nopath_notify, (void *)cdev);
 889                 queue_work(ccw_device_notify_work, &cdev->private->kick_work);
 890         } else if (cdev->private->flags.doverify)
 891                 ccw_device_online_verify(cdev, 0);
 892 }
 893
 894 static void
 895 ccw_device_wait4io_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 896 {
 897         int ret;
 898         struct subchannel *sch;
 899
 900         sch = to_subchannel(cdev->dev.parent);
 901         ccw_device_set_timeout(cdev, 0);
 902         ret = ccw_device_cancel_halt_clear(cdev);
 903         if (ret == -EBUSY) {
 904                 ccw_device_set_timeout(cdev, 3*HZ);
 905                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 906                 return;
 907         }
 908         if (ret == -ENODEV) {
 909                 if (!sch->lpm) {
 910                         PREPARE_WORK(&cdev->private->kick_work,
 911                                      ccw_device_nopath_notify, (void *)cdev);
 912                         queue_work(ccw_device_notify_work,
 913                                    &cdev->private->kick_work);
 914                 } else
 915                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 916                 return;
 917         }
 918         if (cdev->handler)
 919                 cdev->handler(cdev, cdev->private->intparm,
 920                               ERR_PTR(-ETIMEDOUT));
 921         if (!sch->lpm) {
 922                 PREPARE_WORK(&cdev->private->kick_work,
 923                              ccw_device_nopath_notify, (void *)cdev);
 924                 queue_work(ccw_device_notify_work, &cdev->private->kick_work);
 925         } else if (cdev->private->flags.doverify)
 926                 /* Start delayed path verification. */
 927                 ccw_device_online_verify(cdev, 0);
 928 }
 929
 930 static void
 931 ccw_device_wait4io_verify(struct ccw_device *cdev, enum dev_event dev_event)
 932 {
 933         /* When the I/O has terminated, we have to start verification. */
 934         if (cdev->private->options.pgroup)
 935                 cdev->private->flags.doverify = 1;
 936 }
 937
 938 static void
 939 ccw_device_stlck_done(struct ccw_device *cdev, enum dev_event dev_event)
 940 {
 941         struct irb *irb;
 942
 943         switch (dev_event) {
 944         case DEV_EVENT_INTERRUPT:
 945                 irb = (struct irb *) __LC_IRB;
 946                 /* Check for unsolicited interrupt. */
 947                 if ((irb->scsw.stctl ==
 948                      (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) &&
 949                     (!irb->scsw.cc))
 950                         /* FIXME: we should restart stlck here, but this
 951                          * is extremely unlikely ... */
 952                         goto out_wakeup;
 953
 954                 ccw_device_accumulate_irb(cdev, irb);
 955                 /* We don't care about basic sense etc. */
 956                 break;
 957         default: /* timeout */
 958                 break;
 959         }
 960 out_wakeup:
 961         wake_up(&cdev->private->wait_q);
 962 }
 963
 964 static void
 965 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 966 {
 967         struct subchannel *sch;
 968
 969         sch = to_subchannel(cdev->dev.parent);
 970         if (cio_enable_subchannel(sch, sch->schib.pmcw.isc) != 0)
 971                 /* Couldn't enable the subchannel for i/o. Sick device. */
 972                 return;
 973
 974         /* After 60s the device recognition is considered to have failed. */
 975         ccw_device_set_timeout(cdev, 60*HZ);
 976
 977         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 978         ccw_device_sense_id_start(cdev);
 979 }
 980
 981 void
 982 device_trigger_reprobe(struct subchannel *sch)
 983 {
 984         struct ccw_device *cdev;
 985         unsigned long flags;
 986
 987         if (!sch->dev.driver_data)
 988                 return;
 989         cdev = sch->dev.driver_data;
 990         spin_lock_irqsave(&sch->lock, flags);
 991         if (cdev->private->state != DEV_STATE_DISCONNECTED) {
 992                 spin_unlock_irqrestore(&sch->lock, flags);
 993                 return;
 994         }
 995         /* Update some values. */
 996         if (stsch(sch->irq, &sch->schib)) {
 997                 spin_unlock_irqrestore(&sch->lock, flags);
 998                 return;
 999         }
1000         /*
1001          * The pim, pam, pom values may not be accurate, but they are the best
1002          * we have before performing device selection :/
1003          */
1004         sch->lpm = sch->schib.pmcw.pim &
1005                 sch->schib.pmcw.pam &
1006                 sch->schib.pmcw.pom &
1007                 sch->opm;
1008         /* Re-set some bits in the pmcw that were lost. */
1009         sch->schib.pmcw.isc = 3;
1010         sch->schib.pmcw.csense = 1;
1011         sch->schib.pmcw.ena = 0;
1012         if ((sch->lpm & (sch->lpm - 1)) != 0)
1013                 sch->schib.pmcw.mp = 1;
1014         sch->schib.pmcw.intparm = (__u32)(unsigned long)sch;
1015         /* We should also udate ssd info, but this has to wait. */
1016         ccw_device_start_id(cdev, 0);
1017         spin_unlock_irqrestore(&sch->lock, flags);
1018 }
1019
1020 static void
1021 ccw_device_offline_irq(struct ccw_device *cdev, enum dev_event dev_event)
1022 {
1023         struct subchannel *sch;
1024
1025         sch = to_subchannel(cdev->dev.parent);
1026         /*
1027          * An interrupt in state offline means a previous disable was not
1028          * successful. Try again.
1029          */
1030         cio_disable_subchannel(sch);
1031 }
1032
1033 static void
1034 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
1035 {
1036         retry_set_schib(cdev);
1037         cdev->private->state = DEV_STATE_ONLINE;
1038         dev_fsm_event(cdev, dev_event);
1039 }
1040
1041
1042 static void
1043 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
1044 {
1045         ccw_device_set_timeout(cdev, 0);
1046         if (dev_event == DEV_EVENT_NOTOPER)
1047                 cdev->private->state = DEV_STATE_NOT_OPER;
1048         else
1049                 cdev->private->state = DEV_STATE_OFFLINE;
1050         wake_up(&cdev->private->wait_q);
1051 }
1052
1053 static void
1054 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
1055 {
1056         int ret;
1057
1058         ret = ccw_device_cancel_halt_clear(cdev);
1059         switch (ret) {
1060         case 0:
1061                 cdev->private->state = DEV_STATE_OFFLINE;
1062                 wake_up(&cdev->private->wait_q);
1063                 break;
1064         case -ENODEV:
1065                 cdev->private->state = DEV_STATE_NOT_OPER;
1066                 wake_up(&cdev->private->wait_q);
1067                 break;
1068         default:
1069                 ccw_device_set_timeout(cdev, HZ/10);
1070         }
1071 }
1072
1073 /*
1074  * No operation action. This is used e.g. to ignore a timeout event in
1075  * state offline.
1076  */
1077 static void
1078 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1079 {
1080 }
1081
1082 /*
1083  * Bug operation action.
1084  */
1085 static void
1086 ccw_device_bug(struct ccw_device *cdev, enum dev_event dev_event)
1087 {
1088         printk(KERN_EMERG "dev_jumptable[%i][%i] == NULL\n",
1089                cdev->private->state, dev_event);
1090         BUG();
1091 }
1092
1093 /*
1094  * device statemachine
1095  */
1096 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1097         [DEV_STATE_NOT_OPER] = {
1098                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1099                 [DEV_EVENT_INTERRUPT]   = ccw_device_bug,
1100                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1101                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1102         },
1103         [DEV_STATE_SENSE_PGID] = {
1104                 [DEV_EVENT_NOTOPER]     = ccw_device_online_notoper,
1105                 [DEV_EVENT_INTERRUPT]   = ccw_device_sense_pgid_irq,
1106                 [DEV_EVENT_TIMEOUT]     = ccw_device_onoff_timeout,
1107                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1108         },
1109         [DEV_STATE_SENSE_ID] = {
1110                 [DEV_EVENT_NOTOPER]     = ccw_device_recog_notoper,
1111                 [DEV_EVENT_INTERRUPT]   = ccw_device_sense_id_irq,
1112                 [DEV_EVENT_TIMEOUT]     = ccw_device_recog_timeout,
1113                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1114         },
1115         [DEV_STATE_OFFLINE] = {
1116                 [DEV_EVENT_NOTOPER]     = ccw_device_offline_notoper,
1117                 [DEV_EVENT_INTERRUPT]   = ccw_device_offline_irq,
1118                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1119                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1120         },
1121         [DEV_STATE_VERIFY] = {
1122                 [DEV_EVENT_NOTOPER]     = ccw_device_online_notoper,
1123                 [DEV_EVENT_INTERRUPT]   = ccw_device_verify_irq,
1124                 [DEV_EVENT_TIMEOUT]     = ccw_device_onoff_timeout,
1125                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1126         },
1127         [DEV_STATE_ONLINE] = {
1128                 [DEV_EVENT_NOTOPER]     = ccw_device_online_notoper,
1129                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1130                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1131                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1132         },
1133         [DEV_STATE_W4SENSE] = {
1134                 [DEV_EVENT_NOTOPER]     = ccw_device_online_notoper,
1135                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1136                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1137                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1138         },
1139         [DEV_STATE_DISBAND_PGID] = {
1140                 [DEV_EVENT_NOTOPER]     = ccw_device_online_notoper,
1141                 [DEV_EVENT_INTERRUPT]   = ccw_device_disband_irq,
1142                 [DEV_EVENT_TIMEOUT]     = ccw_device_onoff_timeout,
1143                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1144         },
1145         [DEV_STATE_BOXED] = {
1146                 [DEV_EVENT_NOTOPER]     = ccw_device_offline_notoper,
1147                 [DEV_EVENT_INTERRUPT]   = ccw_device_stlck_done,
1148                 [DEV_EVENT_TIMEOUT]     = ccw_device_stlck_done,
1149                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1150         },
1151         /* states to wait for i/o completion before doing something */
1152         [DEV_STATE_CLEAR_VERIFY] = {
1153                 [DEV_EVENT_NOTOPER]     = ccw_device_online_notoper,
1154                 [DEV_EVENT_INTERRUPT]   = ccw_device_clear_verify,
1155                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1156                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1157         },
1158         [DEV_STATE_TIMEOUT_KILL] = {
1159                 [DEV_EVENT_NOTOPER]     = ccw_device_online_notoper,
1160                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1161                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1162                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1163         },
1164         [DEV_STATE_WAIT4IO] = {
1165                 [DEV_EVENT_NOTOPER]     = ccw_device_online_notoper,
1166                 [DEV_EVENT_INTERRUPT]   = ccw_device_wait4io_irq,
1167                 [DEV_EVENT_TIMEOUT]     = ccw_device_wait4io_timeout,
1168                 [DEV_EVENT_VERIFY]      = ccw_device_wait4io_verify,
1169         },
1170         [DEV_STATE_QUIESCE] = {
1171                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1172                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1173                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1174                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1175         },
1176         /* special states for devices gone not operational */
1177         [DEV_STATE_DISCONNECTED] = {
1178                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1179                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1180                 [DEV_EVENT_TIMEOUT]     = ccw_device_bug,
1181                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1182         },
1183         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1184                 [DEV_EVENT_NOTOPER]     = ccw_device_recog_notoper,
1185                 [DEV_EVENT_INTERRUPT]   = ccw_device_sense_id_irq,
1186                 [DEV_EVENT_TIMEOUT]     = ccw_device_recog_timeout,
1187                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1188         },
1189         [DEV_STATE_CMFCHANGE] = {
1190                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1191                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1192                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1193                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1194         },
1195 };
1196
1197 /*
1198  * io_subchannel_irq is called for "real" interrupts or for status
1199  * pending conditions on msch.
1200  */
1201 void
1202 io_subchannel_irq (struct device *pdev)
1203 {
1204         struct ccw_device *cdev;
1205
1206         cdev = to_subchannel(pdev)->dev.driver_data;
1207
1208         CIO_TRACE_EVENT (3, "IRQ");
1209         CIO_TRACE_EVENT (3, pdev->bus_id);
1210         if (cdev)
1211                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1212 }
1213
1214 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);