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         cio_disable_subchannel(sch);
 233         /*
 234          * Now that we tried recognition, we have performed device selection
 235          * through ssch() and the path information is up to date.
 236          */
 237         old_lpm = sch->lpm;
 238
 239         /* Check since device may again have become not operational. */
 240         if (cio_update_schib(sch))
 241                 state = DEV_STATE_NOT_OPER;
 242         else
 243                 sch->lpm = sch->schib.pmcw.pam & sch->opm;
 244
 245         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
 246                 /* Force reprobe on all chpids. */
 247                 old_lpm = 0;
 248         if (sch->lpm != old_lpm)
 249                 __recover_lost_chpids(sch, old_lpm);
 250         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
 251             (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
 252                 cdev->private->flags.recog_done = 1;
 253                 cdev->private->state = DEV_STATE_DISCONNECTED;
 254                 wake_up(&cdev->private->wait_q);
 255                 return;
 256         }
 257         if (cdev->private->flags.resuming) {
 258                 cdev->private->state = state;
 259                 cdev->private->flags.recog_done = 1;
 260                 wake_up(&cdev->private->wait_q);
 261                 return;
 262         }
 263         switch (state) {
 264         case DEV_STATE_NOT_OPER:
 265                 break;
 266         case DEV_STATE_OFFLINE:
 267                 if (!cdev->online) {
 268                         ccw_device_update_sense_data(cdev);
 269                         break;
 270                 }
 271                 cdev->private->state = DEV_STATE_OFFLINE;
 272                 cdev->private->flags.recog_done = 1;
 273                 if (ccw_device_test_sense_data(cdev)) {
 274                         cdev->private->flags.donotify = 1;
 275                         ccw_device_online(cdev);
 276                         wake_up(&cdev->private->wait_q);
 277                 } else {
 278                         ccw_device_update_sense_data(cdev);
 279                         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 280                 }
 281                 return;
 282         case DEV_STATE_BOXED:
 283                 if (cdev->id.cu_type != 0) { /* device was recognized before */
 284                         cdev->private->flags.recog_done = 1;
 285                         cdev->private->state = DEV_STATE_BOXED;
 286                         wake_up(&cdev->private->wait_q);
 287                         return;
 288                 }
 289                 break;
 290         }
 291         cdev->private->state = state;
 292         io_subchannel_recog_done(cdev);
 293         wake_up(&cdev->private->wait_q);
 294 }
 295
 296 /*
 297  * Function called from device_id.c after sense id has completed.
 298  */
 299 void
 300 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
 301 {
 302         switch (err) {
 303         case 0:
 304                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
 305                 break;
 306         case -ETIME:            /* Sense id stopped by timeout. */
 307                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
 308                 break;
 309         default:
 310                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 311                 break;
 312         }
 313 }
 314
 315 int ccw_device_notify(struct ccw_device *cdev, int event)
 316 {
 317         if (!cdev->drv)
 318                 return 0;
 319         if (!cdev->online)
 320                 return 0;
 321         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
 322                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
 323                       event);
 324         return cdev->drv->notify ? cdev->drv->notify(cdev, event) : 0;
 325 }
 326
 327 static void ccw_device_oper_notify(struct ccw_device *cdev)
 328 {
 329         if (ccw_device_notify(cdev, CIO_OPER)) {
 330                 /* Reenable channel measurements, if needed. */
 331                 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
 332                 return;
 333         }
 334         /* Driver doesn't want device back. */
 335         ccw_device_set_notoper(cdev);
 336         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 337 }
 338
 339 /*
 340  * Finished with online/offline processing.
 341  */
 342 static void
 343 ccw_device_done(struct ccw_device *cdev, int state)
 344 {
 345         struct subchannel *sch;
 346
 347         sch = to_subchannel(cdev->dev.parent);
 348
 349         ccw_device_set_timeout(cdev, 0);
 350
 351         if (state != DEV_STATE_ONLINE)
 352                 cio_disable_subchannel(sch);
 353
 354         /* Reset device status. */
 355         memset(&cdev->private->irb, 0, sizeof(struct irb));
 356
 357         cdev->private->state = state;
 358
 359         switch (state) {
 360         case DEV_STATE_BOXED:
 361                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
 362                               cdev->private->dev_id.devno, sch->schid.sch_no);
 363                 if (cdev->online && !ccw_device_notify(cdev, CIO_BOXED))
 364                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 365                 cdev->private->flags.donotify = 0;
 366                 break;
 367         case DEV_STATE_NOT_OPER:
 368                 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
 369                               cdev->private->dev_id.devno, sch->schid.sch_no);
 370                 if (!ccw_device_notify(cdev, CIO_GONE))
 371                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 372                 else
 373                         ccw_device_set_disconnected(cdev);
 374                 cdev->private->flags.donotify = 0;
 375                 break;
 376         case DEV_STATE_DISCONNECTED:
 377                 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
 378                               "%04x\n", cdev->private->dev_id.devno,
 379                               sch->schid.sch_no);
 380                 if (!ccw_device_notify(cdev, CIO_NO_PATH))
 381                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 382                 else
 383                         ccw_device_set_disconnected(cdev);
 384                 cdev->private->flags.donotify = 0;
 385                 break;
 386         default:
 387                 break;
 388         }
 389
 390         if (cdev->private->flags.donotify) {
 391                 cdev->private->flags.donotify = 0;
 392                 ccw_device_oper_notify(cdev);
 393         }
 394         wake_up(&cdev->private->wait_q);
 395 }
 396
 397 /*
 398  * Start device recognition.
 399  */
 400 void ccw_device_recognition(struct ccw_device *cdev)
 401 {
 402         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 403
 404         /*
 405          * We used to start here with a sense pgid to find out whether a device
 406          * is locked by someone else. Unfortunately, the sense pgid command
 407          * code has other meanings on devices predating the path grouping
 408          * algorithm, so we start with sense id and box the device after an
 409          * timeout (or if sense pgid during path verification detects the device
 410          * is locked, as may happen on newer devices).
 411          */
 412         cdev->private->flags.recog_done = 0;
 413         cdev->private->state = DEV_STATE_SENSE_ID;
 414         if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
 415                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 416                 return;
 417         }
 418         ccw_device_sense_id_start(cdev);
 419 }
 420
 421 /*
 422  * Handle events for states that use the ccw request infrastructure.
 423  */
 424 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
 425 {
 426         switch (e) {
 427         case DEV_EVENT_NOTOPER:
 428                 ccw_request_notoper(cdev);
 429                 break;
 430         case DEV_EVENT_INTERRUPT:
 431                 ccw_request_handler(cdev);
 432                 break;
 433         case DEV_EVENT_TIMEOUT:
 434                 ccw_request_timeout(cdev);
 435                 break;
 436         default:
 437                 break;
 438         }
 439 }
 440
 441 void
 442 ccw_device_verify_done(struct ccw_device *cdev, int err)
 443 {
 444         struct subchannel *sch;
 445
 446         sch = to_subchannel(cdev->dev.parent);
 447         /* Update schib - pom may have changed. */
 448         if (cio_update_schib(sch)) {
 449                 err = -ENODEV;
 450                 goto callback;
 451         }
 452         /* Update lpm with verified path mask. */
 453         sch->lpm = sch->vpm;
 454         /* Repeat path verification? */
 455         if (cdev->private->flags.doverify) {
 456                 ccw_device_verify_start(cdev);
 457                 return;
 458         }
 459 callback:
 460         switch (err) {
 461         case 0:
 462                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 463                 /* Deliver fake irb to device driver, if needed. */
 464                 if (cdev->private->flags.fake_irb) {
 465                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 466                         cdev->private->irb.scsw.cmd.cc = 1;
 467                         cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC;
 468                         cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND;
 469                         cdev->private->irb.scsw.cmd.stctl =
 470                                 SCSW_STCTL_STATUS_PEND;
 471                         cdev->private->flags.fake_irb = 0;
 472                         if (cdev->handler)
 473                                 cdev->handler(cdev, cdev->private->intparm,
 474                                               &cdev->private->irb);
 475                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 476                 }
 477                 break;
 478         case -ETIME:
 479         case -EUSERS:
 480                 /* Reset oper notify indication after verify error. */
 481                 cdev->private->flags.donotify = 0;
 482                 ccw_device_done(cdev, DEV_STATE_BOXED);
 483                 break;
 484         case -EACCES:
 485                 /* Reset oper notify indication after verify error. */
 486                 cdev->private->flags.donotify = 0;
 487                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
 488                 break;
 489         default:
 490                 /* Reset oper notify indication after verify error. */
 491                 cdev->private->flags.donotify = 0;
 492                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 493                 break;
 494         }
 495 }
 496
 497 /*
 498  * Get device online.
 499  */
 500 int
 501 ccw_device_online(struct ccw_device *cdev)
 502 {
 503         struct subchannel *sch;
 504         int ret;
 505
 506         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 507             (cdev->private->state != DEV_STATE_BOXED))
 508                 return -EINVAL;
 509         sch = to_subchannel(cdev->dev.parent);
 510         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
 511         if (ret != 0) {
 512                 /* Couldn't enable the subchannel for i/o. Sick device. */
 513                 if (ret == -ENODEV)
 514                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 515                 return ret;
 516         }
 517         /* Start initial path verification. */
 518         cdev->private->state = DEV_STATE_VERIFY;
 519         ccw_device_verify_start(cdev);
 520         return 0;
 521 }
 522
 523 void
 524 ccw_device_disband_done(struct ccw_device *cdev, int err)
 525 {
 526         switch (err) {
 527         case 0:
 528                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 529                 break;
 530         case -ETIME:
 531                 ccw_device_done(cdev, DEV_STATE_BOXED);
 532                 break;
 533         default:
 534                 cdev->private->flags.donotify = 0;
 535                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 536                 break;
 537         }
 538 }
 539
 540 /*
 541  * Shutdown device.
 542  */
 543 int
 544 ccw_device_offline(struct ccw_device *cdev)
 545 {
 546         struct subchannel *sch;
 547
 548         /* Allow ccw_device_offline while disconnected. */
 549         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
 550             cdev->private->state == DEV_STATE_NOT_OPER) {
 551                 cdev->private->flags.donotify = 0;
 552                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 553                 return 0;
 554         }
 555         if (cdev->private->state == DEV_STATE_BOXED) {
 556                 ccw_device_done(cdev, DEV_STATE_BOXED);
 557                 return 0;
 558         }
 559         if (ccw_device_is_orphan(cdev)) {
 560                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 561                 return 0;
 562         }
 563         sch = to_subchannel(cdev->dev.parent);
 564         if (cio_update_schib(sch))
 565                 return -ENODEV;
 566         if (scsw_actl(&sch->schib.scsw) != 0)
 567                 return -EBUSY;
 568         if (cdev->private->state != DEV_STATE_ONLINE)
 569                 return -EINVAL;
 570         /* Are we doing path grouping? */
 571         if (!cdev->private->flags.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 not operational event in non-special state.
 584  */
 585 static void ccw_device_generic_notoper(struct ccw_device *cdev,
 586                                        enum dev_event dev_event)
 587 {
 588         if (!ccw_device_notify(cdev, CIO_GONE))
 589                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 590         else
 591                 ccw_device_set_disconnected(cdev);
 592 }
 593
 594 /*
 595  * Handle path verification event in offline state.
 596  */
 597 static void ccw_device_offline_verify(struct ccw_device *cdev,
 598                                       enum dev_event dev_event)
 599 {
 600         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 601
 602         css_schedule_eval(sch->schid);
 603 }
 604
 605 /*
 606  * Handle path verification event.
 607  */
 608 static void
 609 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 610 {
 611         struct subchannel *sch;
 612
 613         if (cdev->private->state == DEV_STATE_W4SENSE) {
 614                 cdev->private->flags.doverify = 1;
 615                 return;
 616         }
 617         sch = to_subchannel(cdev->dev.parent);
 618         /*
 619          * Since we might not just be coming from an interrupt from the
 620          * subchannel we have to update the schib.
 621          */
 622         if (cio_update_schib(sch)) {
 623                 ccw_device_verify_done(cdev, -ENODEV);
 624                 return;
 625         }
 626
 627         if (scsw_actl(&sch->schib.scsw) != 0 ||
 628             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
 629             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
 630                 /*
 631                  * No final status yet or final status not yet delivered
 632                  * to the device driver. Can't do path verfication now,
 633                  * delay until final status was delivered.
 634                  */
 635                 cdev->private->flags.doverify = 1;
 636                 return;
 637         }
 638         /* Device is idle, we can do the path verification. */
 639         cdev->private->state = DEV_STATE_VERIFY;
 640         ccw_device_verify_start(cdev);
 641 }
 642
 643 /*
 644  * Got an interrupt for a normal io (state online).
 645  */
 646 static void
 647 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 648 {
 649         struct irb *irb;
 650         int is_cmd;
 651
 652         irb = (struct irb *) __LC_IRB;
 653         is_cmd = !scsw_is_tm(&irb->scsw);
 654         /* Check for unsolicited interrupt. */
 655         if (!scsw_is_solicited(&irb->scsw)) {
 656                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
 657                     !irb->esw.esw0.erw.cons) {
 658                         /* Unit check but no sense data. Need basic sense. */
 659                         if (ccw_device_do_sense(cdev, irb) != 0)
 660                                 goto call_handler_unsol;
 661                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
 662                         cdev->private->state = DEV_STATE_W4SENSE;
 663                         cdev->private->intparm = 0;
 664                         return;
 665                 }
 666 call_handler_unsol:
 667                 if (cdev->handler)
 668                         cdev->handler (cdev, 0, irb);
 669                 if (cdev->private->flags.doverify)
 670                         ccw_device_online_verify(cdev, 0);
 671                 return;
 672         }
 673         /* Accumulate status and find out if a basic sense is needed. */
 674         ccw_device_accumulate_irb(cdev, irb);
 675         if (is_cmd && cdev->private->flags.dosense) {
 676                 if (ccw_device_do_sense(cdev, irb) == 0) {
 677                         cdev->private->state = DEV_STATE_W4SENSE;
 678                 }
 679                 return;
 680         }
 681         /* Call the handler. */
 682         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 683                 /* Start delayed path verification. */
 684                 ccw_device_online_verify(cdev, 0);
 685 }
 686
 687 /*
 688  * Got an timeout in online state.
 689  */
 690 static void
 691 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 692 {
 693         int ret;
 694
 695         ccw_device_set_timeout(cdev, 0);
 696         ret = ccw_device_cancel_halt_clear(cdev);
 697         if (ret == -EBUSY) {
 698                 ccw_device_set_timeout(cdev, 3*HZ);
 699                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 700                 return;
 701         }
 702         if (ret == -ENODEV)
 703                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 704         else if (cdev->handler)
 705                 cdev->handler(cdev, cdev->private->intparm,
 706                               ERR_PTR(-ETIMEDOUT));
 707 }
 708
 709 /*
 710  * Got an interrupt for a basic sense.
 711  */
 712 static void
 713 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 714 {
 715         struct irb *irb;
 716
 717         irb = (struct irb *) __LC_IRB;
 718         /* Check for unsolicited interrupt. */
 719         if (scsw_stctl(&irb->scsw) ==
 720             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 721                 if (scsw_cc(&irb->scsw) == 1)
 722                         /* Basic sense hasn't started. Try again. */
 723                         ccw_device_do_sense(cdev, irb);
 724                 else {
 725                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
 726                                       "interrupt during w4sense...\n",
 727                                       cdev->private->dev_id.ssid,
 728                                       cdev->private->dev_id.devno);
 729                         if (cdev->handler)
 730                                 cdev->handler (cdev, 0, irb);
 731                 }
 732                 return;
 733         }
 734         /*
 735          * Check if a halt or clear has been issued in the meanwhile. If yes,
 736          * only deliver the halt/clear interrupt to the device driver as if it
 737          * had killed the original request.
 738          */
 739         if (scsw_fctl(&irb->scsw) &
 740             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
 741                 cdev->private->flags.dosense = 0;
 742                 memset(&cdev->private->irb, 0, sizeof(struct irb));
 743                 ccw_device_accumulate_irb(cdev, irb);
 744                 goto call_handler;
 745         }
 746         /* Add basic sense info to irb. */
 747         ccw_device_accumulate_basic_sense(cdev, irb);
 748         if (cdev->private->flags.dosense) {
 749                 /* Another basic sense is needed. */
 750                 ccw_device_do_sense(cdev, irb);
 751                 return;
 752         }
 753 call_handler:
 754         cdev->private->state = DEV_STATE_ONLINE;
 755         /* In case sensing interfered with setting the device online */
 756         wake_up(&cdev->private->wait_q);
 757         /* Call the handler. */
 758         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 759                 /* Start delayed path verification. */
 760                 ccw_device_online_verify(cdev, 0);
 761 }
 762
 763 static void
 764 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 765 {
 766         struct subchannel *sch;
 767
 768         sch = to_subchannel(cdev->dev.parent);
 769         ccw_device_set_timeout(cdev, 0);
 770         /* Start delayed path verification. */
 771         ccw_device_online_verify(cdev, 0);
 772         /* OK, i/o is dead now. Call interrupt handler. */
 773         if (cdev->handler)
 774                 cdev->handler(cdev, cdev->private->intparm,
 775                               ERR_PTR(-EIO));
 776 }
 777
 778 static void
 779 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 780 {
 781         int ret;
 782
 783         ret = ccw_device_cancel_halt_clear(cdev);
 784         if (ret == -EBUSY) {
 785                 ccw_device_set_timeout(cdev, 3*HZ);
 786                 return;
 787         }
 788         /* Start delayed path verification. */
 789         ccw_device_online_verify(cdev, 0);
 790         if (cdev->handler)
 791                 cdev->handler(cdev, cdev->private->intparm,
 792                               ERR_PTR(-EIO));
 793 }
 794
 795 void ccw_device_kill_io(struct ccw_device *cdev)
 796 {
 797         int ret;
 798
 799         ret = ccw_device_cancel_halt_clear(cdev);
 800         if (ret == -EBUSY) {
 801                 ccw_device_set_timeout(cdev, 3*HZ);
 802                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 803                 return;
 804         }
 805         /* Start delayed path verification. */
 806         ccw_device_online_verify(cdev, 0);
 807         if (cdev->handler)
 808                 cdev->handler(cdev, cdev->private->intparm,
 809                               ERR_PTR(-EIO));
 810 }
 811
 812 static void
 813 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 814 {
 815         /* Start verification after current task finished. */
 816         cdev->private->flags.doverify = 1;
 817 }
 818
 819 static void
 820 ccw_device_stlck_done(struct ccw_device *cdev, enum dev_event dev_event)
 821 {
 822         struct irb *irb;
 823
 824         switch (dev_event) {
 825         case DEV_EVENT_INTERRUPT:
 826                 irb = (struct irb *) __LC_IRB;
 827                 /* Check for unsolicited interrupt. */
 828                 if ((scsw_stctl(&irb->scsw) ==
 829                      (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) &&
 830                     (!scsw_cc(&irb->scsw)))
 831                         /* FIXME: we should restart stlck here, but this
 832                          * is extremely unlikely ... */
 833                         goto out_wakeup;
 834
 835                 ccw_device_accumulate_irb(cdev, irb);
 836                 /* We don't care about basic sense etc. */
 837                 break;
 838         default: /* timeout */
 839                 break;
 840         }
 841 out_wakeup:
 842         wake_up(&cdev->private->wait_q);
 843 }
 844
 845 static void
 846 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 847 {
 848         struct subchannel *sch;
 849
 850         sch = to_subchannel(cdev->dev.parent);
 851         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
 852                 /* Couldn't enable the subchannel for i/o. Sick device. */
 853                 return;
 854         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 855         ccw_device_sense_id_start(cdev);
 856 }
 857
 858 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
 859 {
 860         struct subchannel *sch;
 861
 862         if (cdev->private->state != DEV_STATE_DISCONNECTED)
 863                 return;
 864
 865         sch = to_subchannel(cdev->dev.parent);
 866         /* Update some values. */
 867         if (cio_update_schib(sch))
 868                 return;
 869         /*
 870          * The pim, pam, pom values may not be accurate, but they are the best
 871          * we have before performing device selection :/
 872          */
 873         sch->lpm = sch->schib.pmcw.pam & sch->opm;
 874         /*
 875          * Use the initial configuration since we can't be shure that the old
 876          * paths are valid.
 877          */
 878         io_subchannel_init_config(sch);
 879         if (cio_commit_config(sch))
 880                 return;
 881
 882         /* We should also udate ssd info, but this has to wait. */
 883         /* Check if this is another device which appeared on the same sch. */
 884         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
 885                 css_schedule_eval(sch->schid);
 886         else
 887                 ccw_device_start_id(cdev, 0);
 888 }
 889
 890 static void ccw_device_disabled_irq(struct ccw_device *cdev,
 891                                     enum dev_event dev_event)
 892 {
 893         struct subchannel *sch;
 894
 895         sch = to_subchannel(cdev->dev.parent);
 896         /*
 897          * An interrupt in a disabled state means a previous disable was not
 898          * successful - should not happen, but we try to disable again.
 899          */
 900         cio_disable_subchannel(sch);
 901 }
 902
 903 static void
 904 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
 905 {
 906         retry_set_schib(cdev);
 907         cdev->private->state = DEV_STATE_ONLINE;
 908         dev_fsm_event(cdev, dev_event);
 909 }
 910
 911 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
 912                                        enum dev_event dev_event)
 913 {
 914         cmf_retry_copy_block(cdev);
 915         cdev->private->state = DEV_STATE_ONLINE;
 916         dev_fsm_event(cdev, dev_event);
 917 }
 918
 919 static void
 920 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
 921 {
 922         ccw_device_set_timeout(cdev, 0);
 923         if (dev_event == DEV_EVENT_NOTOPER)
 924                 cdev->private->state = DEV_STATE_NOT_OPER;
 925         else
 926                 cdev->private->state = DEV_STATE_OFFLINE;
 927         wake_up(&cdev->private->wait_q);
 928 }
 929
 930 static void
 931 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 932 {
 933         int ret;
 934
 935         ret = ccw_device_cancel_halt_clear(cdev);
 936         switch (ret) {
 937         case 0:
 938                 cdev->private->state = DEV_STATE_OFFLINE;
 939                 wake_up(&cdev->private->wait_q);
 940                 break;
 941         case -ENODEV:
 942                 cdev->private->state = DEV_STATE_NOT_OPER;
 943                 wake_up(&cdev->private->wait_q);
 944                 break;
 945         default:
 946                 ccw_device_set_timeout(cdev, HZ/10);
 947         }
 948 }
 949
 950 /*
 951  * No operation action. This is used e.g. to ignore a timeout event in
 952  * state offline.
 953  */
 954 static void
 955 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
 956 {
 957 }
 958
 959 /*
 960  * device statemachine
 961  */
 962 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
 963         [DEV_STATE_NOT_OPER] = {
 964                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
 965                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
 966                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
 967                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 968         },
 969         [DEV_STATE_SENSE_PGID] = {
 970                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 971                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 972                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 973                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 974         },
 975         [DEV_STATE_SENSE_ID] = {
 976                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 977                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 978                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 979                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
 980         },
 981         [DEV_STATE_OFFLINE] = {
 982                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
 983                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
 984                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
 985                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
 986         },
 987         [DEV_STATE_VERIFY] = {
 988                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
 989                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
 990                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
 991                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
 992         },
 993         [DEV_STATE_ONLINE] = {
 994                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
 995                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
 996                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
 997                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
 998         },
 999         [DEV_STATE_W4SENSE] = {
1000                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1001                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1002                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1003                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1004         },
1005         [DEV_STATE_DISBAND_PGID] = {
1006                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1007                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1008                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1009                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1010         },
1011         [DEV_STATE_BOXED] = {
1012                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1013                 [DEV_EVENT_INTERRUPT]   = ccw_device_stlck_done,
1014                 [DEV_EVENT_TIMEOUT]     = ccw_device_stlck_done,
1015                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1016         },
1017         /* states to wait for i/o completion before doing something */
1018         [DEV_STATE_TIMEOUT_KILL] = {
1019                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1020                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1021                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1022                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1023         },
1024         [DEV_STATE_QUIESCE] = {
1025                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1026                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1027                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1028                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1029         },
1030         /* special states for devices gone not operational */
1031         [DEV_STATE_DISCONNECTED] = {
1032                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1033                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1034                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1035                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1036         },
1037         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1038                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1039                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1040                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1041                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1042         },
1043         [DEV_STATE_CMFCHANGE] = {
1044                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1045                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1046                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1047                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1048         },
1049         [DEV_STATE_CMFUPDATE] = {
1050                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1051                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1052                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1053                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1054         },
1055 };
1056
1057 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);