drivers/s390/cio/device_fsm.c

   1 /*
   2  * drivers/s390/cio/device_fsm.c
   3  * finite state machine for device handling
   4  *
   5  *    Copyright IBM Corp. 2002,2008
   6  *    Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
   7  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/jiffies.h>
  13 #include <linux/string.h>
  14
  15 #include <asm/ccwdev.h>
  16 #include <asm/cio.h>
  17 #include <asm/chpid.h>
  18
  19 #include "cio.h"
  20 #include "cio_debug.h"
  21 #include "css.h"
  22 #include "device.h"
  23 #include "chsc.h"
  24 #include "ioasm.h"
  25 #include "chp.h"
  26
  27 static int timeout_log_enabled;
  28
  29 static int __init ccw_timeout_log_setup(char *unused)
  30 {
  31         timeout_log_enabled = 1;
  32         return 1;
  33 }
  34
  35 __setup("ccw_timeout_log", ccw_timeout_log_setup);
  36
  37 static void ccw_timeout_log(struct ccw_device *cdev)
  38 {
  39         struct schib schib;
  40         struct subchannel *sch;
  41         struct io_subchannel_private *private;
  42         union orb *orb;
  43         int cc;
  44
  45         sch = to_subchannel(cdev->dev.parent);
  46         private = to_io_private(sch);
  47         orb = &private->orb;
  48         cc = stsch(sch->schid, &schib);
  49
  50         printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
  51                "device information:\n", get_clock());
  52         printk(KERN_WARNING "cio: orb:\n");
  53         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  54                        orb, sizeof(*orb), 0);
  55         printk(KERN_WARNING "cio: ccw device bus id: %s\n",
  56                dev_name(&cdev->dev));
  57         printk(KERN_WARNING "cio: subchannel bus id: %s\n",
  58                dev_name(&sch->dev));
  59         printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
  60                "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
  61
  62         if (orb->tm.b) {
  63                 printk(KERN_WARNING "cio: orb indicates transport mode\n");
  64                 printk(KERN_WARNING "cio: last tcw:\n");
  65                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  66                                (void *)(addr_t)orb->tm.tcw,
  67                                sizeof(struct tcw), 0);
  68         } else {
  69                 printk(KERN_WARNING "cio: orb indicates command mode\n");
  70                 if ((void *)(addr_t)orb->cmd.cpa == &private->sense_ccw ||
  71                     (void *)(addr_t)orb->cmd.cpa == cdev->private->iccws)
  72                         printk(KERN_WARNING "cio: last channel program "
  73                                "(intern):\n");
  74                 else
  75                         printk(KERN_WARNING "cio: last channel program:\n");
  76
  77                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  78                                (void *)(addr_t)orb->cmd.cpa,
  79                                sizeof(struct ccw1), 0);
  80         }
  81         printk(KERN_WARNING "cio: ccw device state: %d\n",
  82                cdev->private->state);
  83         printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
  84         printk(KERN_WARNING "cio: schib:\n");
  85         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  86                        &schib, sizeof(schib), 0);
  87         printk(KERN_WARNING "cio: ccw device flags:\n");
  88         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  89                        &cdev->private->flags, sizeof(cdev->private->flags), 0);
  90 }
  91
  92 /*
  93  * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
  94  */
  95 static void
  96 ccw_device_timeout(unsigned long data)
  97 {
  98         struct ccw_device *cdev;
  99
 100         cdev = (struct ccw_device *) data;
 101         spin_lock_irq(cdev->ccwlock);
 102         if (timeout_log_enabled)
 103                 ccw_timeout_log(cdev);
 104         dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
 105         spin_unlock_irq(cdev->ccwlock);
 106 }
 107
 108 /*
 109  * Set timeout
 110  */
 111 void
 112 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
 113 {
 114         if (expires == 0) {
 115                 del_timer(&cdev->private->timer);
 116                 return;
 117         }
 118         if (timer_pending(&cdev->private->timer)) {
 119                 if (mod_timer(&cdev->private->timer, jiffies + expires))
 120                         return;
 121         }
 122         cdev->private->timer.function = ccw_device_timeout;
 123         cdev->private->timer.data = (unsigned long) cdev;
 124         cdev->private->timer.expires = jiffies + expires;
 125         add_timer(&cdev->private->timer);
 126 }
 127
 128 /*
 129  * Cancel running i/o. This is called repeatedly since halt/clear are
 130  * asynchronous operations. We do one try with cio_cancel, two tries
 131  * with cio_halt, 255 tries with cio_clear. If everythings fails panic.
 132  * Returns 0 if device now idle, -ENODEV for device not operational and
 133  * -EBUSY if an interrupt is expected (either from halt/clear or from a
 134  * status pending).
 135  */
 136 int
 137 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
 138 {
 139         struct subchannel *sch;
 140         int ret;
 141
 142         sch = to_subchannel(cdev->dev.parent);
 143         if (cio_update_schib(sch))
 144                 return -ENODEV;
 145         if (!sch->schib.pmcw.ena)
 146                 /* Not operational -> done. */
 147                 return 0;
 148         /* Stage 1: cancel io. */
 149         if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_HALT_PEND) &&
 150             !(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
 151                 if (!scsw_is_tm(&sch->schib.scsw)) {
 152                         ret = cio_cancel(sch);
 153                         if (ret != -EINVAL)
 154                                 return ret;
 155                 }
 156                 /* cancel io unsuccessful or not applicable (transport mode).
 157                  * Continue with asynchronous instructions. */
 158                 cdev->private->iretry = 3;      /* 3 halt retries. */
 159         }
 160         if (!(scsw_actl(&sch->schib.scsw) & SCSW_ACTL_CLEAR_PEND)) {
 161                 /* Stage 2: halt io. */
 162                 if (cdev->private->iretry) {
 163                         cdev->private->iretry--;
 164                         ret = cio_halt(sch);
 165                         if (ret != -EBUSY)
 166                                 return (ret == 0) ? -EBUSY : ret;
 167                 }
 168                 /* halt io unsuccessful. */
 169                 cdev->private->iretry = 255;    /* 255 clear retries. */
 170         }
 171         /* Stage 3: clear io. */
 172         if (cdev->private->iretry) {
 173                 cdev->private->iretry--;
 174                 ret = cio_clear (sch);
 175                 return (ret == 0) ? -EBUSY : ret;
 176         }
 177         panic("Can't stop i/o on subchannel.\n");
 178 }
 179
 180 void ccw_device_update_sense_data(struct ccw_device *cdev)
 181 {
 182         memset(&cdev->id, 0, sizeof(cdev->id));
 183         cdev->id.cu_type   = cdev->private->senseid.cu_type;
 184         cdev->id.cu_model  = cdev->private->senseid.cu_model;
 185         cdev->id.dev_type  = cdev->private->senseid.dev_type;
 186         cdev->id.dev_model = cdev->private->senseid.dev_model;
 187 }
 188
 189 int ccw_device_test_sense_data(struct ccw_device *cdev)
 190 {
 191         return cdev->id.cu_type == cdev->private->senseid.cu_type &&
 192                 cdev->id.cu_model == cdev->private->senseid.cu_model &&
 193                 cdev->id.dev_type == cdev->private->senseid.dev_type &&
 194                 cdev->id.dev_model == cdev->private->senseid.dev_model;
 195 }
 196
 197 /*
 198  * The machine won't give us any notification by machine check if a chpid has
 199  * been varied online on the SE so we have to find out by magic (i. e. driving
 200  * the channel subsystem to device selection and updating our path masks).
 201  */
 202 static void
 203 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
 204 {
 205         int mask, i;
 206         struct chp_id chpid;
 207
 208         chp_id_init(&chpid);
 209         for (i = 0; i<8; i++) {
 210                 mask = 0x80 >> i;
 211                 if (!(sch->lpm & mask))
 212                         continue;
 213                 if (old_lpm & mask)
 214                         continue;
 215                 chpid.id = sch->schib.pmcw.chpid[i];
 216                 if (!chp_is_registered(chpid))
 217                         css_schedule_eval_all();
 218         }
 219 }
 220
 221 /*
 222  * Stop device recognition.
 223  */
 224 static void
 225 ccw_device_recog_done(struct ccw_device *cdev, int state)
 226 {
 227         struct subchannel *sch;
 228         int old_lpm;
 229
 230         sch = to_subchannel(cdev->dev.parent);
 231
 232         if (cio_disable_subchannel(sch))
 233                 state = DEV_STATE_NOT_OPER;
 234         /*
 235          * Now that we tried recognition, we have performed device selection
 236          * through ssch() and the path information is up to date.
 237          */
 238         old_lpm = sch->lpm;
 239
 240         /* Check since device may again have become not operational. */
 241         if (cio_update_schib(sch))
 242                 state = DEV_STATE_NOT_OPER;
 243         else
 244                 sch->lpm = sch->schib.pmcw.pam & sch->opm;
 245
 246         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
 247                 /* Force reprobe on all chpids. */
 248                 old_lpm = 0;
 249         if (sch->lpm != old_lpm)
 250                 __recover_lost_chpids(sch, old_lpm);
 251         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
 252             (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
 253                 cdev->private->flags.recog_done = 1;
 254                 cdev->private->state = DEV_STATE_DISCONNECTED;
 255                 wake_up(&cdev->private->wait_q);
 256                 return;
 257         }
 258         if (cdev->private->flags.resuming) {
 259                 cdev->private->state = state;
 260                 cdev->private->flags.recog_done = 1;
 261                 wake_up(&cdev->private->wait_q);
 262                 return;
 263         }
 264         switch (state) {
 265         case DEV_STATE_NOT_OPER:
 266                 break;
 267         case DEV_STATE_OFFLINE:
 268                 if (!cdev->online) {
 269                         ccw_device_update_sense_data(cdev);
 270                         break;
 271                 }
 272                 cdev->private->state = DEV_STATE_OFFLINE;
 273                 cdev->private->flags.recog_done = 1;
 274                 if (ccw_device_test_sense_data(cdev)) {
 275                         cdev->private->flags.donotify = 1;
 276                         ccw_device_online(cdev);
 277                         wake_up(&cdev->private->wait_q);
 278                 } else {
 279                         ccw_device_update_sense_data(cdev);
 280                         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 281                 }
 282                 return;
 283         case DEV_STATE_BOXED:
 284                 if (cdev->id.cu_type != 0) { /* device was recognized before */
 285                         cdev->private->flags.recog_done = 1;
 286                         cdev->private->state = DEV_STATE_BOXED;
 287                         wake_up(&cdev->private->wait_q);
 288                         return;
 289                 }
 290                 break;
 291         }
 292         cdev->private->state = state;
 293         io_subchannel_recog_done(cdev);
 294         wake_up(&cdev->private->wait_q);
 295 }
 296
 297 /*
 298  * Function called from device_id.c after sense id has completed.
 299  */
 300 void
 301 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
 302 {
 303         switch (err) {
 304         case 0:
 305                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
 306                 break;
 307         case -ETIME:            /* Sense id stopped by timeout. */
 308                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
 309                 break;
 310         default:
 311                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 312                 break;
 313         }
 314 }
 315
 316 int ccw_device_notify(struct ccw_device *cdev, int event)
 317 {
 318         if (!cdev->drv)
 319                 return 0;
 320         if (!cdev->online)
 321                 return 0;
 322         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
 323                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
 324                       event);
 325         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
 326 }
 327
 328 static void ccw_device_oper_notify(struct ccw_device *cdev)
 329 {
 330         if (ccw_device_notify(cdev, CIO_OPER)) {
 331                 /* Reenable channel measurements, if needed. */
 332                 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
 333                 return;
 334         }
 335         /* Driver doesn't want device back. */
 336         ccw_device_set_notoper(cdev);
 337         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 338 }
 339
 340 /*
 341  * Finished with online/offline processing.
 342  */
 343 static void
 344 ccw_device_done(struct ccw_device *cdev, int state)
 345 {
 346         struct subchannel *sch;
 347
 348         sch = to_subchannel(cdev->dev.parent);
 349
 350         ccw_device_set_timeout(cdev, 0);
 351
 352         if (state != DEV_STATE_ONLINE)
 353                 cio_disable_subchannel(sch);
 354
 355         /* Reset device status. */
 356         memset(&cdev->private->irb, 0, sizeof(struct irb));
 357
 358         cdev->private->state = state;
 359
 360         switch (state) {
 361         case DEV_STATE_BOXED:
 362                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
 363                               cdev->private->dev_id.devno, sch->schid.sch_no);
 364                 if (cdev->online && !ccw_device_notify(cdev, CIO_BOXED))
 365                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 366                 cdev->private->flags.donotify = 0;
 367                 break;
 368         case DEV_STATE_NOT_OPER:
 369                 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
 370                               cdev->private->dev_id.devno, sch->schid.sch_no);
 371                 if (!ccw_device_notify(cdev, CIO_GONE))
 372                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 373                 else
 374                         ccw_device_set_disconnected(cdev);
 375                 cdev->private->flags.donotify = 0;
 376                 break;
 377         case DEV_STATE_DISCONNECTED:
 378                 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
 379                               "%04x\n", cdev->private->dev_id.devno,
 380                               sch->schid.sch_no);
 381                 if (!ccw_device_notify(cdev, CIO_NO_PATH))
 382                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 383                 else
 384                         ccw_device_set_disconnected(cdev);
 385                 cdev->private->flags.donotify = 0;
 386                 break;
 387         default:
 388                 break;
 389         }
 390
 391         if (cdev->private->flags.donotify) {
 392                 cdev->private->flags.donotify = 0;
 393                 ccw_device_oper_notify(cdev);
 394         }
 395         wake_up(&cdev->private->wait_q);
 396 }
 397
 398 /*
 399  * Start device recognition.
 400  */
 401 void ccw_device_recognition(struct ccw_device *cdev)
 402 {
 403         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 404
 405         /*
 406          * We used to start here with a sense pgid to find out whether a device
 407          * is locked by someone else. Unfortunately, the sense pgid command
 408          * code has other meanings on devices predating the path grouping
 409          * algorithm, so we start with sense id and box the device after an
 410          * timeout (or if sense pgid during path verification detects the device
 411          * is locked, as may happen on newer devices).
 412          */
 413         cdev->private->flags.recog_done = 0;
 414         cdev->private->state = DEV_STATE_SENSE_ID;
 415         if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
 416                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 417                 return;
 418         }
 419         ccw_device_sense_id_start(cdev);
 420 }
 421
 422 /*
 423  * Handle events for states that use the ccw request infrastructure.
 424  */
 425 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
 426 {
 427         switch (e) {
 428         case DEV_EVENT_NOTOPER:
 429                 ccw_request_notoper(cdev);
 430                 break;
 431         case DEV_EVENT_INTERRUPT:
 432                 ccw_request_handler(cdev);
 433                 break;
 434         case DEV_EVENT_TIMEOUT:
 435                 ccw_request_timeout(cdev);
 436                 break;
 437         default:
 438                 break;
 439         }
 440 }
 441
 442 void
 443 ccw_device_verify_done(struct ccw_device *cdev, int err)
 444 {
 445         struct subchannel *sch;
 446
 447         sch = to_subchannel(cdev->dev.parent);
 448         /* Update schib - pom may have changed. */
 449         if (cio_update_schib(sch)) {
 450                 err = -ENODEV;
 451                 goto callback;
 452         }
 453         /* Update lpm with verified path mask. */
 454         sch->lpm = sch->vpm;
 455         /* Repeat path verification? */
 456         if (cdev->private->flags.doverify) {
 457                 ccw_device_verify_start(cdev);
 458                 return;
 459         }
 460 callback:
 461         switch (err) {
 462         case 0:
 463                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 464                 /* Deliver fake irb to device driver, if needed. */
 465                 if (cdev->private->flags.fake_irb) {
 466                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 467                         cdev->private->irb.scsw.cmd.cc = 1;
 468                         cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC;
 469                         cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND;
 470                         cdev->private->irb.scsw.cmd.stctl =
 471                                 SCSW_STCTL_STATUS_PEND;
 472                         cdev->private->flags.fake_irb = 0;
 473                         if (cdev->handler)
 474                                 cdev->handler(cdev, cdev->private->intparm,
 475                                               &cdev->private->irb);
 476                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 477                 }
 478                 break;
 479         case -ETIME:
 480         case -EUSERS:
 481                 /* Reset oper notify indication after verify error. */
 482                 cdev->private->flags.donotify = 0;
 483                 ccw_device_done(cdev, DEV_STATE_BOXED);
 484                 break;
 485         case -EACCES:
 486                 /* Reset oper notify indication after verify error. */
 487                 cdev->private->flags.donotify = 0;
 488                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
 489                 break;
 490         default:
 491                 /* Reset oper notify indication after verify error. */
 492                 cdev->private->flags.donotify = 0;
 493                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 494                 break;
 495         }
 496 }
 497
 498 /*
 499  * Get device online.
 500  */
 501 int
 502 ccw_device_online(struct ccw_device *cdev)
 503 {
 504         struct subchannel *sch;
 505         int ret;
 506
 507         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 508             (cdev->private->state != DEV_STATE_BOXED))
 509                 return -EINVAL;
 510         sch = to_subchannel(cdev->dev.parent);
 511         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
 512         if (ret != 0) {
 513                 /* Couldn't enable the subchannel for i/o. Sick device. */
 514                 if (ret == -ENODEV)
 515                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 516                 return ret;
 517         }
 518         /* Start initial path verification. */
 519         cdev->private->state = DEV_STATE_VERIFY;
 520         ccw_device_verify_start(cdev);
 521         return 0;
 522 }
 523
 524 void
 525 ccw_device_disband_done(struct ccw_device *cdev, int err)
 526 {
 527         switch (err) {
 528         case 0:
 529                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 530                 break;
 531         case -ETIME:
 532                 ccw_device_done(cdev, DEV_STATE_BOXED);
 533                 break;
 534         default:
 535                 cdev->private->flags.donotify = 0;
 536                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 537                 break;
 538         }
 539 }
 540
 541 /*
 542  * Shutdown device.
 543  */
 544 int
 545 ccw_device_offline(struct ccw_device *cdev)
 546 {
 547         struct subchannel *sch;
 548
 549         /* Allow ccw_device_offline while disconnected. */
 550         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
 551             cdev->private->state == DEV_STATE_NOT_OPER) {
 552                 cdev->private->flags.donotify = 0;
 553                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 554                 return 0;
 555         }
 556         if (cdev->private->state == DEV_STATE_BOXED) {
 557                 ccw_device_done(cdev, DEV_STATE_BOXED);
 558                 return 0;
 559         }
 560         if (ccw_device_is_orphan(cdev)) {
 561                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 562                 return 0;
 563         }
 564         sch = to_subchannel(cdev->dev.parent);
 565         if (cio_update_schib(sch))
 566                 return -ENODEV;
 567         if (scsw_actl(&sch->schib.scsw) != 0)
 568                 return -EBUSY;
 569         if (cdev->private->state != DEV_STATE_ONLINE)
 570                 return -EINVAL;
 571         /* Are we doing path grouping? */
 572         if (!cdev->private->flags.pgroup) {
 573                 /* No, set state offline immediately. */
 574                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 575                 return 0;
 576         }
 577         /* Start Set Path Group commands. */
 578         cdev->private->state = DEV_STATE_DISBAND_PGID;
 579         ccw_device_disband_start(cdev);
 580         return 0;
 581 }
 582
 583 /*
 584  * Handle not operational event in non-special state.
 585  */
 586 static void ccw_device_generic_notoper(struct ccw_device *cdev,
 587                                        enum dev_event dev_event)
 588 {
 589         if (!ccw_device_notify(cdev, CIO_GONE))
 590                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 591         else
 592                 ccw_device_set_disconnected(cdev);
 593 }
 594
 595 /*
 596  * Handle path verification event in offline state.
 597  */
 598 static void ccw_device_offline_verify(struct ccw_device *cdev,
 599                                       enum dev_event dev_event)
 600 {
 601         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 602
 603         css_schedule_eval(sch->schid);
 604 }
 605
 606 /*
 607  * Handle path verification event.
 608  */
 609 static void
 610 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 611 {
 612         struct subchannel *sch;
 613
 614         if (cdev->private->state == DEV_STATE_W4SENSE) {
 615                 cdev->private->flags.doverify = 1;
 616                 return;
 617         }
 618         sch = to_subchannel(cdev->dev.parent);
 619         /*
 620          * Since we might not just be coming from an interrupt from the
 621          * subchannel we have to update the schib.
 622          */
 623         if (cio_update_schib(sch)) {
 624                 ccw_device_verify_done(cdev, -ENODEV);
 625                 return;
 626         }
 627
 628         if (scsw_actl(&sch->schib.scsw) != 0 ||
 629             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
 630             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
 631                 /*
 632                  * No final status yet or final status not yet delivered
 633                  * to the device driver. Can't do path verfication now,
 634                  * delay until final status was delivered.
 635                  */
 636                 cdev->private->flags.doverify = 1;
 637                 return;
 638         }
 639         /* Device is idle, we can do the path verification. */
 640         cdev->private->state = DEV_STATE_VERIFY;
 641         ccw_device_verify_start(cdev);
 642 }
 643
 644 /*
 645  * Handle path verification event in boxed state.
 646  */
 647 static void ccw_device_boxed_verify(struct ccw_device *cdev,
 648                                     enum dev_event dev_event)
 649 {
 650         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 651
 652         if (cdev->online) {
 653                 if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
 654                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 655                 else
 656                         ccw_device_online_verify(cdev, dev_event);
 657         } else
 658                 css_schedule_eval(sch->schid);
 659 }
 660
 661 /*
 662  * Got an interrupt for a normal io (state online).
 663  */
 664 static void
 665 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 666 {
 667         struct irb *irb;
 668         int is_cmd;
 669
 670         irb = (struct irb *) __LC_IRB;
 671         is_cmd = !scsw_is_tm(&irb->scsw);
 672         /* Check for unsolicited interrupt. */
 673         if (!scsw_is_solicited(&irb->scsw)) {
 674                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
 675                     !irb->esw.esw0.erw.cons) {
 676                         /* Unit check but no sense data. Need basic sense. */
 677                         if (ccw_device_do_sense(cdev, irb) != 0)
 678                                 goto call_handler_unsol;
 679                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
 680                         cdev->private->state = DEV_STATE_W4SENSE;
 681                         cdev->private->intparm = 0;
 682                         return;
 683                 }
 684 call_handler_unsol:
 685                 if (cdev->handler)
 686                         cdev->handler (cdev, 0, irb);
 687                 if (cdev->private->flags.doverify)
 688                         ccw_device_online_verify(cdev, 0);
 689                 return;
 690         }
 691         /* Accumulate status and find out if a basic sense is needed. */
 692         ccw_device_accumulate_irb(cdev, irb);
 693         if (is_cmd && cdev->private->flags.dosense) {
 694                 if (ccw_device_do_sense(cdev, irb) == 0) {
 695                         cdev->private->state = DEV_STATE_W4SENSE;
 696                 }
 697                 return;
 698         }
 699         /* Call the handler. */
 700         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 701                 /* Start delayed path verification. */
 702                 ccw_device_online_verify(cdev, 0);
 703 }
 704
 705 /*
 706  * Got an timeout in online state.
 707  */
 708 static void
 709 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 710 {
 711         int ret;
 712
 713         ccw_device_set_timeout(cdev, 0);
 714         ret = ccw_device_cancel_halt_clear(cdev);
 715         if (ret == -EBUSY) {
 716                 ccw_device_set_timeout(cdev, 3*HZ);
 717                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 718                 return;
 719         }
 720         if (ret == -ENODEV)
 721                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 722         else if (cdev->handler)
 723                 cdev->handler(cdev, cdev->private->intparm,
 724                               ERR_PTR(-ETIMEDOUT));
 725 }
 726
 727 /*
 728  * Got an interrupt for a basic sense.
 729  */
 730 static void
 731 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 732 {
 733         struct irb *irb;
 734
 735         irb = (struct irb *) __LC_IRB;
 736         /* Check for unsolicited interrupt. */
 737         if (scsw_stctl(&irb->scsw) ==
 738             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 739                 if (scsw_cc(&irb->scsw) == 1)
 740                         /* Basic sense hasn't started. Try again. */
 741                         ccw_device_do_sense(cdev, irb);
 742                 else {
 743                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
 744                                       "interrupt during w4sense...\n",
 745                                       cdev->private->dev_id.ssid,
 746                                       cdev->private->dev_id.devno);
 747                         if (cdev->handler)
 748                                 cdev->handler (cdev, 0, irb);
 749                 }
 750                 return;
 751         }
 752         /*
 753          * Check if a halt or clear has been issued in the meanwhile. If yes,
 754          * only deliver the halt/clear interrupt to the device driver as if it
 755          * had killed the original request.
 756          */
 757         if (scsw_fctl(&irb->scsw) &
 758             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
 759                 cdev->private->flags.dosense = 0;
 760                 memset(&cdev->private->irb, 0, sizeof(struct irb));
 761                 ccw_device_accumulate_irb(cdev, irb);
 762                 goto call_handler;
 763         }
 764         /* Add basic sense info to irb. */
 765         ccw_device_accumulate_basic_sense(cdev, irb);
 766         if (cdev->private->flags.dosense) {
 767                 /* Another basic sense is needed. */
 768                 ccw_device_do_sense(cdev, irb);
 769                 return;
 770         }
 771 call_handler:
 772         cdev->private->state = DEV_STATE_ONLINE;
 773         /* In case sensing interfered with setting the device online */
 774         wake_up(&cdev->private->wait_q);
 775         /* Call the handler. */
 776         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 777                 /* Start delayed path verification. */
 778                 ccw_device_online_verify(cdev, 0);
 779 }
 780
 781 static void
 782 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 783 {
 784         struct subchannel *sch;
 785
 786         sch = to_subchannel(cdev->dev.parent);
 787         ccw_device_set_timeout(cdev, 0);
 788         /* Start delayed path verification. */
 789         ccw_device_online_verify(cdev, 0);
 790         /* OK, i/o is dead now. Call interrupt handler. */
 791         if (cdev->handler)
 792                 cdev->handler(cdev, cdev->private->intparm,
 793                               ERR_PTR(-EIO));
 794 }
 795
 796 static void
 797 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 798 {
 799         int ret;
 800
 801         ret = ccw_device_cancel_halt_clear(cdev);
 802         if (ret == -EBUSY) {
 803                 ccw_device_set_timeout(cdev, 3*HZ);
 804                 return;
 805         }
 806         /* Start delayed path verification. */
 807         ccw_device_online_verify(cdev, 0);
 808         if (cdev->handler)
 809                 cdev->handler(cdev, cdev->private->intparm,
 810                               ERR_PTR(-EIO));
 811 }
 812
 813 void ccw_device_kill_io(struct ccw_device *cdev)
 814 {
 815         int ret;
 816
 817         ret = ccw_device_cancel_halt_clear(cdev);
 818         if (ret == -EBUSY) {
 819                 ccw_device_set_timeout(cdev, 3*HZ);
 820                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 821                 return;
 822         }
 823         /* Start delayed path verification. */
 824         ccw_device_online_verify(cdev, 0);
 825         if (cdev->handler)
 826                 cdev->handler(cdev, cdev->private->intparm,
 827                               ERR_PTR(-EIO));
 828 }
 829
 830 static void
 831 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 832 {
 833         /* Start verification after current task finished. */
 834         cdev->private->flags.doverify = 1;
 835 }
 836
 837 static void
 838 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 839 {
 840         struct subchannel *sch;
 841
 842         sch = to_subchannel(cdev->dev.parent);
 843         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
 844                 /* Couldn't enable the subchannel for i/o. Sick device. */
 845                 return;
 846         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 847         ccw_device_sense_id_start(cdev);
 848 }
 849
 850 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
 851 {
 852         struct subchannel *sch;
 853
 854         if (cdev->private->state != DEV_STATE_DISCONNECTED)
 855                 return;
 856
 857         sch = to_subchannel(cdev->dev.parent);
 858         /* Update some values. */
 859         if (cio_update_schib(sch))
 860                 return;
 861         /*
 862          * The pim, pam, pom values may not be accurate, but they are the best
 863          * we have before performing device selection :/
 864          */
 865         sch->lpm = sch->schib.pmcw.pam & sch->opm;
 866         /*
 867          * Use the initial configuration since we can't be shure that the old
 868          * paths are valid.
 869          */
 870         io_subchannel_init_config(sch);
 871         if (cio_commit_config(sch))
 872                 return;
 873
 874         /* We should also udate ssd info, but this has to wait. */
 875         /* Check if this is another device which appeared on the same sch. */
 876         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
 877                 css_schedule_eval(sch->schid);
 878         else
 879                 ccw_device_start_id(cdev, 0);
 880 }
 881
 882 static void ccw_device_disabled_irq(struct ccw_device *cdev,
 883                                     enum dev_event dev_event)
 884 {
 885         struct subchannel *sch;
 886
 887         sch = to_subchannel(cdev->dev.parent);
 888         /*
 889          * An interrupt in a disabled state means a previous disable was not
 890          * successful - should not happen, but we try to disable again.
 891          */
 892         cio_disable_subchannel(sch);
 893 }
 894
 895 static void
 896 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
 897 {
 898         retry_set_schib(cdev);
 899         cdev->private->state = DEV_STATE_ONLINE;
 900         dev_fsm_event(cdev, dev_event);
 901 }
 902
 903 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
 904                                        enum dev_event dev_event)
 905 {
 906         cmf_retry_copy_block(cdev);
 907         cdev->private->state = DEV_STATE_ONLINE;
 908         dev_fsm_event(cdev, dev_event);
 909 }
 910
 911 static void
 912 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
 913 {
 914         ccw_device_set_timeout(cdev, 0);
 915         cdev->private->state = DEV_STATE_NOT_OPER;
 916         wake_up(&cdev->private->wait_q);
 917 }
 918
 919 static void
 920 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 921 {
 922         int ret;
 923
 924         ret = ccw_device_cancel_halt_clear(cdev);
 925         if (ret == -EBUSY) {
 926                 ccw_device_set_timeout(cdev, HZ/10);
 927         } else {
 928                 cdev->private->state = DEV_STATE_NOT_OPER;
 929                 wake_up(&cdev->private->wait_q);
 930         }
 931 }
 932
 933 /*
 934  * No operation action. This is used e.g. to ignore a timeout event in
 935  * state offline.
 936  */
 937 static void
 938 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
 939 {
 940 }
 941
 942 /*
 943  * device statemachine
 944  */
 945 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
 946         [DEV_STATE_NOT_OPER] = {
 947                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
 948                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
 949                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
 950                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 951         },
 952         [DEV_STATE_SENSE_PGID] = {
 953                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 954                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 955                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 956                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 957         },
 958         [DEV_STATE_SENSE_ID] = {
 959                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 960                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 961                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 962                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 963         },
 964         [DEV_STATE_OFFLINE] = {
 965                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
 966                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
 967                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
 968                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
 969         },
 970         [DEV_STATE_VERIFY] = {
 971                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 972                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 973                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 974                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
 975         },
 976         [DEV_STATE_ONLINE] = {
 977                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
 978                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
 979                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
 980                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
 981         },
 982         [DEV_STATE_W4SENSE] = {
 983                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
 984                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
 985                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
 986                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
 987         },
 988         [DEV_STATE_DISBAND_PGID] = {
 989                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 990                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 991                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 992                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 993         },
 994         [DEV_STATE_BOXED] = {
 995                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
 996                 [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
 997                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
 998                 [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
 999         },
1000         /* states to wait for i/o completion before doing something */
1001         [DEV_STATE_TIMEOUT_KILL] = {
1002                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1003                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1004                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1005                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1006         },
1007         [DEV_STATE_QUIESCE] = {
1008                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1009                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1010                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1011                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1012         },
1013         /* special states for devices gone not operational */
1014         [DEV_STATE_DISCONNECTED] = {
1015                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1016                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1017                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1018                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1019         },
1020         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1021                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1022                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1023                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1024                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1025         },
1026         [DEV_STATE_CMFCHANGE] = {
1027                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1028                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1029                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1030                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1031         },
1032         [DEV_STATE_CMFUPDATE] = {
1033                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1034                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1035                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1036                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1037         },
1038         [DEV_STATE_STEAL_LOCK] = {
1039                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1040                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1041                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1042                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1043         },
1044 };
1045
1046 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);