drivers/s390/cio/device_fsm.c

   1 /*
   2  * finite state machine for device handling
   3  *
   4  *    Copyright IBM Corp. 2002, 2008
   5  *    Author(s): Cornelia Huck (cornelia.huck@de.ibm.com)
   6  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/init.h>
  11 #include <linux/jiffies.h>
  12 #include <linux/string.h>
  13
  14 #include <asm/ccwdev.h>
  15 #include <asm/cio.h>
  16 #include <asm/chpid.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 "chp.h"
  25
  26 static int timeout_log_enabled;
  27
  28 static int __init ccw_timeout_log_setup(char *unused)
  29 {
  30         timeout_log_enabled = 1;
  31         return 1;
  32 }
  33
  34 __setup("ccw_timeout_log", ccw_timeout_log_setup);
  35
  36 static void ccw_timeout_log(struct ccw_device *cdev)
  37 {
  38         struct schib schib;
  39         struct subchannel *sch;
  40         struct io_subchannel_private *private;
  41         union orb *orb;
  42         int cc;
  43
  44         sch = to_subchannel(cdev->dev.parent);
  45         private = to_io_private(sch);
  46         orb = &private->orb;
  47         cc = stsch(sch->schid, &schib);
  48
  49         printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, "
  50                "device information:\n", get_tod_clock());
  51         printk(KERN_WARNING "cio: orb:\n");
  52         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  53                        orb, sizeof(*orb), 0);
  54         printk(KERN_WARNING "cio: ccw device bus id: %s\n",
  55                dev_name(&cdev->dev));
  56         printk(KERN_WARNING "cio: subchannel bus id: %s\n",
  57                dev_name(&sch->dev));
  58         printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
  59                "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
  60
  61         if (orb->tm.b) {
  62                 printk(KERN_WARNING "cio: orb indicates transport mode\n");
  63                 printk(KERN_WARNING "cio: last tcw:\n");
  64                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  65                                (void *)(addr_t)orb->tm.tcw,
  66                                sizeof(struct tcw), 0);
  67         } else {
  68                 printk(KERN_WARNING "cio: orb indicates command mode\n");
  69                 if ((void *)(addr_t)orb->cmd.cpa == &private->sense_ccw ||
  70                     (void *)(addr_t)orb->cmd.cpa == cdev->private->iccws)
  71                         printk(KERN_WARNING "cio: last channel program "
  72                                "(intern):\n");
  73                 else
  74                         printk(KERN_WARNING "cio: last channel program:\n");
  75
  76                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  77                                (void *)(addr_t)orb->cmd.cpa,
  78                                sizeof(struct ccw1), 0);
  79         }
  80         printk(KERN_WARNING "cio: ccw device state: %d\n",
  81                cdev->private->state);
  82         printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
  83         printk(KERN_WARNING "cio: schib:\n");
  84         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  85                        &schib, sizeof(schib), 0);
  86         printk(KERN_WARNING "cio: ccw device flags:\n");
  87         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  88                        &cdev->private->flags, sizeof(cdev->private->flags), 0);
  89 }
  90
  91 /*
  92  * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
  93  */
  94 static void
  95 ccw_device_timeout(unsigned long data)
  96 {
  97         struct ccw_device *cdev;
  98
  99         cdev = (struct ccw_device *) data;
 100         spin_lock_irq(cdev->ccwlock);
 101         if (timeout_log_enabled)
 102                 ccw_timeout_log(cdev);
 103         dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
 104         spin_unlock_irq(cdev->ccwlock);
 105 }
 106
 107 /*
 108  * Set timeout
 109  */
 110 void
 111 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
 112 {
 113         if (expires == 0) {
 114                 del_timer(&cdev->private->timer);
 115                 return;
 116         }
 117         if (timer_pending(&cdev->private->timer)) {
 118                 if (mod_timer(&cdev->private->timer, jiffies + expires))
 119                         return;
 120         }
 121         cdev->private->timer.function = ccw_device_timeout;
 122         cdev->private->timer.data = (unsigned long) cdev;
 123         cdev->private->timer.expires = jiffies + expires;
 124         add_timer(&cdev->private->timer);
 125 }
 126
 127 int
 128 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
 129 {
 130         struct subchannel *sch;
 131         int ret;
 132
 133         sch = to_subchannel(cdev->dev.parent);
 134         ret = cio_cancel_halt_clear(sch, &cdev->private->iretry);
 135
 136         if (ret == -EIO)
 137                 CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
 138                               cdev->private->dev_id.ssid,
 139                               cdev->private->dev_id.devno);
 140
 141         return ret;
 142 }
 143
 144 void ccw_device_update_sense_data(struct ccw_device *cdev)
 145 {
 146         memset(&cdev->id, 0, sizeof(cdev->id));
 147         cdev->id.cu_type   = cdev->private->senseid.cu_type;
 148         cdev->id.cu_model  = cdev->private->senseid.cu_model;
 149         cdev->id.dev_type  = cdev->private->senseid.dev_type;
 150         cdev->id.dev_model = cdev->private->senseid.dev_model;
 151 }
 152
 153 int ccw_device_test_sense_data(struct ccw_device *cdev)
 154 {
 155         return cdev->id.cu_type == cdev->private->senseid.cu_type &&
 156                 cdev->id.cu_model == cdev->private->senseid.cu_model &&
 157                 cdev->id.dev_type == cdev->private->senseid.dev_type &&
 158                 cdev->id.dev_model == cdev->private->senseid.dev_model;
 159 }
 160
 161 /*
 162  * The machine won't give us any notification by machine check if a chpid has
 163  * been varied online on the SE so we have to find out by magic (i. e. driving
 164  * the channel subsystem to device selection and updating our path masks).
 165  */
 166 static void
 167 __recover_lost_chpids(struct subchannel *sch, int old_lpm)
 168 {
 169         int mask, i;
 170         struct chp_id chpid;
 171
 172         chp_id_init(&chpid);
 173         for (i = 0; i<8; i++) {
 174                 mask = 0x80 >> i;
 175                 if (!(sch->lpm & mask))
 176                         continue;
 177                 if (old_lpm & mask)
 178                         continue;
 179                 chpid.id = sch->schib.pmcw.chpid[i];
 180                 if (!chp_is_registered(chpid))
 181                         css_schedule_eval_all();
 182         }
 183 }
 184
 185 /*
 186  * Stop device recognition.
 187  */
 188 static void
 189 ccw_device_recog_done(struct ccw_device *cdev, int state)
 190 {
 191         struct subchannel *sch;
 192         int old_lpm;
 193
 194         sch = to_subchannel(cdev->dev.parent);
 195
 196         if (cio_disable_subchannel(sch))
 197                 state = DEV_STATE_NOT_OPER;
 198         /*
 199          * Now that we tried recognition, we have performed device selection
 200          * through ssch() and the path information is up to date.
 201          */
 202         old_lpm = sch->lpm;
 203
 204         /* Check since device may again have become not operational. */
 205         if (cio_update_schib(sch))
 206                 state = DEV_STATE_NOT_OPER;
 207         else
 208                 sch->lpm = sch->schib.pmcw.pam & sch->opm;
 209
 210         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID)
 211                 /* Force reprobe on all chpids. */
 212                 old_lpm = 0;
 213         if (sch->lpm != old_lpm)
 214                 __recover_lost_chpids(sch, old_lpm);
 215         if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID &&
 216             (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) {
 217                 cdev->private->flags.recog_done = 1;
 218                 cdev->private->state = DEV_STATE_DISCONNECTED;
 219                 wake_up(&cdev->private->wait_q);
 220                 return;
 221         }
 222         if (cdev->private->flags.resuming) {
 223                 cdev->private->state = state;
 224                 cdev->private->flags.recog_done = 1;
 225                 wake_up(&cdev->private->wait_q);
 226                 return;
 227         }
 228         switch (state) {
 229         case DEV_STATE_NOT_OPER:
 230                 break;
 231         case DEV_STATE_OFFLINE:
 232                 if (!cdev->online) {
 233                         ccw_device_update_sense_data(cdev);
 234                         break;
 235                 }
 236                 cdev->private->state = DEV_STATE_OFFLINE;
 237                 cdev->private->flags.recog_done = 1;
 238                 if (ccw_device_test_sense_data(cdev)) {
 239                         cdev->private->flags.donotify = 1;
 240                         ccw_device_online(cdev);
 241                         wake_up(&cdev->private->wait_q);
 242                 } else {
 243                         ccw_device_update_sense_data(cdev);
 244                         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 245                 }
 246                 return;
 247         case DEV_STATE_BOXED:
 248                 if (cdev->id.cu_type != 0) { /* device was recognized before */
 249                         cdev->private->flags.recog_done = 1;
 250                         cdev->private->state = DEV_STATE_BOXED;
 251                         wake_up(&cdev->private->wait_q);
 252                         return;
 253                 }
 254                 break;
 255         }
 256         cdev->private->state = state;
 257         io_subchannel_recog_done(cdev);
 258         wake_up(&cdev->private->wait_q);
 259 }
 260
 261 /*
 262  * Function called from device_id.c after sense id has completed.
 263  */
 264 void
 265 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
 266 {
 267         switch (err) {
 268         case 0:
 269                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
 270                 break;
 271         case -ETIME:            /* Sense id stopped by timeout. */
 272                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
 273                 break;
 274         default:
 275                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 276                 break;
 277         }
 278 }
 279
 280 /**
 281   * ccw_device_notify() - inform the device's driver about an event
 282   * @cdev: device for which an event occurred
 283   * @event: event that occurred
 284   *
 285   * Returns:
 286   *   -%EINVAL if the device is offline or has no driver.
 287   *   -%EOPNOTSUPP if the device's driver has no notifier registered.
 288   *   %NOTIFY_OK if the driver wants to keep the device.
 289   *   %NOTIFY_BAD if the driver doesn't want to keep the device.
 290   */
 291 int ccw_device_notify(struct ccw_device *cdev, int event)
 292 {
 293         int ret = -EINVAL;
 294
 295         if (!cdev->drv)
 296                 goto out;
 297         if (!cdev->online)
 298                 goto out;
 299         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
 300                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
 301                       event);
 302         if (!cdev->drv->notify) {
 303                 ret = -EOPNOTSUPP;
 304                 goto out;
 305         }
 306         if (cdev->drv->notify(cdev, event))
 307                 ret = NOTIFY_OK;
 308         else
 309                 ret = NOTIFY_BAD;
 310 out:
 311         return ret;
 312 }
 313
 314 static void ccw_device_oper_notify(struct ccw_device *cdev)
 315 {
 316         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 317
 318         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
 319                 /* Reenable channel measurements, if needed. */
 320                 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
 321                 /* Save indication for new paths. */
 322                 cdev->private->path_new_mask = sch->vpm;
 323                 return;
 324         }
 325         /* Driver doesn't want device back. */
 326         ccw_device_set_notoper(cdev);
 327         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 328 }
 329
 330 /*
 331  * Finished with online/offline processing.
 332  */
 333 static void
 334 ccw_device_done(struct ccw_device *cdev, int state)
 335 {
 336         struct subchannel *sch;
 337
 338         sch = to_subchannel(cdev->dev.parent);
 339
 340         ccw_device_set_timeout(cdev, 0);
 341
 342         if (state != DEV_STATE_ONLINE)
 343                 cio_disable_subchannel(sch);
 344
 345         /* Reset device status. */
 346         memset(&cdev->private->irb, 0, sizeof(struct irb));
 347
 348         cdev->private->state = state;
 349
 350         switch (state) {
 351         case DEV_STATE_BOXED:
 352                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
 353                               cdev->private->dev_id.devno, sch->schid.sch_no);
 354                 if (cdev->online &&
 355                     ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
 356                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 357                 cdev->private->flags.donotify = 0;
 358                 break;
 359         case DEV_STATE_NOT_OPER:
 360                 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
 361                               cdev->private->dev_id.devno, sch->schid.sch_no);
 362                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 363                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 364                 else
 365                         ccw_device_set_disconnected(cdev);
 366                 cdev->private->flags.donotify = 0;
 367                 break;
 368         case DEV_STATE_DISCONNECTED:
 369                 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
 370                               "%04x\n", cdev->private->dev_id.devno,
 371                               sch->schid.sch_no);
 372                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
 373                         cdev->private->state = DEV_STATE_NOT_OPER;
 374                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 375                 } else
 376                         ccw_device_set_disconnected(cdev);
 377                 cdev->private->flags.donotify = 0;
 378                 break;
 379         default:
 380                 break;
 381         }
 382
 383         if (cdev->private->flags.donotify) {
 384                 cdev->private->flags.donotify = 0;
 385                 ccw_device_oper_notify(cdev);
 386         }
 387         wake_up(&cdev->private->wait_q);
 388 }
 389
 390 /*
 391  * Start device recognition.
 392  */
 393 void ccw_device_recognition(struct ccw_device *cdev)
 394 {
 395         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 396
 397         /*
 398          * We used to start here with a sense pgid to find out whether a device
 399          * is locked by someone else. Unfortunately, the sense pgid command
 400          * code has other meanings on devices predating the path grouping
 401          * algorithm, so we start with sense id and box the device after an
 402          * timeout (or if sense pgid during path verification detects the device
 403          * is locked, as may happen on newer devices).
 404          */
 405         cdev->private->flags.recog_done = 0;
 406         cdev->private->state = DEV_STATE_SENSE_ID;
 407         if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) {
 408                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 409                 return;
 410         }
 411         ccw_device_sense_id_start(cdev);
 412 }
 413
 414 /*
 415  * Handle events for states that use the ccw request infrastructure.
 416  */
 417 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
 418 {
 419         switch (e) {
 420         case DEV_EVENT_NOTOPER:
 421                 ccw_request_notoper(cdev);
 422                 break;
 423         case DEV_EVENT_INTERRUPT:
 424                 ccw_request_handler(cdev);
 425                 break;
 426         case DEV_EVENT_TIMEOUT:
 427                 ccw_request_timeout(cdev);
 428                 break;
 429         default:
 430                 break;
 431         }
 432 }
 433
 434 static void ccw_device_report_path_events(struct ccw_device *cdev)
 435 {
 436         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 437         int path_event[8];
 438         int chp, mask;
 439
 440         for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
 441                 path_event[chp] = PE_NONE;
 442                 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
 443                         path_event[chp] |= PE_PATH_GONE;
 444                 if (mask & cdev->private->path_new_mask & sch->vpm)
 445                         path_event[chp] |= PE_PATH_AVAILABLE;
 446                 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
 447                         path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
 448         }
 449         if (cdev->online && cdev->drv->path_event)
 450                 cdev->drv->path_event(cdev, path_event);
 451 }
 452
 453 static void ccw_device_reset_path_events(struct ccw_device *cdev)
 454 {
 455         cdev->private->path_gone_mask = 0;
 456         cdev->private->path_new_mask = 0;
 457         cdev->private->pgid_reset_mask = 0;
 458 }
 459
 460 static void create_fake_irb(struct irb *irb, int type)
 461 {
 462         memset(irb, 0, sizeof(*irb));
 463         if (type == FAKE_CMD_IRB) {
 464                 struct cmd_scsw *scsw = &irb->scsw.cmd;
 465                 scsw->cc = 1;
 466                 scsw->fctl = SCSW_FCTL_START_FUNC;
 467                 scsw->actl = SCSW_ACTL_START_PEND;
 468                 scsw->stctl = SCSW_STCTL_STATUS_PEND;
 469         } else if (type == FAKE_TM_IRB) {
 470                 struct tm_scsw *scsw = &irb->scsw.tm;
 471                 scsw->x = 1;
 472                 scsw->cc = 1;
 473                 scsw->fctl = SCSW_FCTL_START_FUNC;
 474                 scsw->actl = SCSW_ACTL_START_PEND;
 475                 scsw->stctl = SCSW_STCTL_STATUS_PEND;
 476         }
 477 }
 478
 479 void ccw_device_verify_done(struct ccw_device *cdev, int err)
 480 {
 481         struct subchannel *sch;
 482
 483         sch = to_subchannel(cdev->dev.parent);
 484         /* Update schib - pom may have changed. */
 485         if (cio_update_schib(sch)) {
 486                 err = -ENODEV;
 487                 goto callback;
 488         }
 489         /* Update lpm with verified path mask. */
 490         sch->lpm = sch->vpm;
 491         /* Repeat path verification? */
 492         if (cdev->private->flags.doverify) {
 493                 ccw_device_verify_start(cdev);
 494                 return;
 495         }
 496 callback:
 497         switch (err) {
 498         case 0:
 499                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 500                 /* Deliver fake irb to device driver, if needed. */
 501                 if (cdev->private->flags.fake_irb) {
 502                         create_fake_irb(&cdev->private->irb,
 503                                         cdev->private->flags.fake_irb);
 504                         cdev->private->flags.fake_irb = 0;
 505                         if (cdev->handler)
 506                                 cdev->handler(cdev, cdev->private->intparm,
 507                                               &cdev->private->irb);
 508                         memset(&cdev->private->irb, 0, sizeof(struct irb));
 509                 }
 510                 ccw_device_report_path_events(cdev);
 511                 break;
 512         case -ETIME:
 513         case -EUSERS:
 514                 /* Reset oper notify indication after verify error. */
 515                 cdev->private->flags.donotify = 0;
 516                 ccw_device_done(cdev, DEV_STATE_BOXED);
 517                 break;
 518         case -EACCES:
 519                 /* Reset oper notify indication after verify error. */
 520                 cdev->private->flags.donotify = 0;
 521                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
 522                 break;
 523         default:
 524                 /* Reset oper notify indication after verify error. */
 525                 cdev->private->flags.donotify = 0;
 526                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 527                 break;
 528         }
 529         ccw_device_reset_path_events(cdev);
 530 }
 531
 532 /*
 533  * Get device online.
 534  */
 535 int
 536 ccw_device_online(struct ccw_device *cdev)
 537 {
 538         struct subchannel *sch;
 539         int ret;
 540
 541         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 542             (cdev->private->state != DEV_STATE_BOXED))
 543                 return -EINVAL;
 544         sch = to_subchannel(cdev->dev.parent);
 545         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
 546         if (ret != 0) {
 547                 /* Couldn't enable the subchannel for i/o. Sick device. */
 548                 if (ret == -ENODEV)
 549                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 550                 return ret;
 551         }
 552         /* Start initial path verification. */
 553         cdev->private->state = DEV_STATE_VERIFY;
 554         ccw_device_verify_start(cdev);
 555         return 0;
 556 }
 557
 558 void
 559 ccw_device_disband_done(struct ccw_device *cdev, int err)
 560 {
 561         switch (err) {
 562         case 0:
 563                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 564                 break;
 565         case -ETIME:
 566                 ccw_device_done(cdev, DEV_STATE_BOXED);
 567                 break;
 568         default:
 569                 cdev->private->flags.donotify = 0;
 570                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 571                 break;
 572         }
 573 }
 574
 575 /*
 576  * Shutdown device.
 577  */
 578 int
 579 ccw_device_offline(struct ccw_device *cdev)
 580 {
 581         struct subchannel *sch;
 582
 583         /* Allow ccw_device_offline while disconnected. */
 584         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
 585             cdev->private->state == DEV_STATE_NOT_OPER) {
 586                 cdev->private->flags.donotify = 0;
 587                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 588                 return 0;
 589         }
 590         if (cdev->private->state == DEV_STATE_BOXED) {
 591                 ccw_device_done(cdev, DEV_STATE_BOXED);
 592                 return 0;
 593         }
 594         if (ccw_device_is_orphan(cdev)) {
 595                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 596                 return 0;
 597         }
 598         sch = to_subchannel(cdev->dev.parent);
 599         if (cio_update_schib(sch))
 600                 return -ENODEV;
 601         if (scsw_actl(&sch->schib.scsw) != 0)
 602                 return -EBUSY;
 603         if (cdev->private->state != DEV_STATE_ONLINE)
 604                 return -EINVAL;
 605         /* Are we doing path grouping? */
 606         if (!cdev->private->flags.pgroup) {
 607                 /* No, set state offline immediately. */
 608                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 609                 return 0;
 610         }
 611         /* Start Set Path Group commands. */
 612         cdev->private->state = DEV_STATE_DISBAND_PGID;
 613         ccw_device_disband_start(cdev);
 614         return 0;
 615 }
 616
 617 /*
 618  * Handle not operational event in non-special state.
 619  */
 620 static void ccw_device_generic_notoper(struct ccw_device *cdev,
 621                                        enum dev_event dev_event)
 622 {
 623         if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 624                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 625         else
 626                 ccw_device_set_disconnected(cdev);
 627 }
 628
 629 /*
 630  * Handle path verification event in offline state.
 631  */
 632 static void ccw_device_offline_verify(struct ccw_device *cdev,
 633                                       enum dev_event dev_event)
 634 {
 635         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 636
 637         css_schedule_eval(sch->schid);
 638 }
 639
 640 /*
 641  * Handle path verification event.
 642  */
 643 static void
 644 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 645 {
 646         struct subchannel *sch;
 647
 648         if (cdev->private->state == DEV_STATE_W4SENSE) {
 649                 cdev->private->flags.doverify = 1;
 650                 return;
 651         }
 652         sch = to_subchannel(cdev->dev.parent);
 653         /*
 654          * Since we might not just be coming from an interrupt from the
 655          * subchannel we have to update the schib.
 656          */
 657         if (cio_update_schib(sch)) {
 658                 ccw_device_verify_done(cdev, -ENODEV);
 659                 return;
 660         }
 661
 662         if (scsw_actl(&sch->schib.scsw) != 0 ||
 663             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
 664             (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) {
 665                 /*
 666                  * No final status yet or final status not yet delivered
 667                  * to the device driver. Can't do path verification now,
 668                  * delay until final status was delivered.
 669                  */
 670                 cdev->private->flags.doverify = 1;
 671                 return;
 672         }
 673         /* Device is idle, we can do the path verification. */
 674         cdev->private->state = DEV_STATE_VERIFY;
 675         ccw_device_verify_start(cdev);
 676 }
 677
 678 /*
 679  * Handle path verification event in boxed state.
 680  */
 681 static void ccw_device_boxed_verify(struct ccw_device *cdev,
 682                                     enum dev_event dev_event)
 683 {
 684         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 685
 686         if (cdev->online) {
 687                 if (cio_enable_subchannel(sch, (u32) (addr_t) sch))
 688                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 689                 else
 690                         ccw_device_online_verify(cdev, dev_event);
 691         } else
 692                 css_schedule_eval(sch->schid);
 693 }
 694
 695 /*
 696  * Pass interrupt to device driver.
 697  */
 698 static int ccw_device_call_handler(struct ccw_device *cdev)
 699 {
 700         unsigned int stctl;
 701         int ending_status;
 702
 703         /*
 704          * we allow for the device action handler if .
 705          *  - we received ending status
 706          *  - the action handler requested to see all interrupts
 707          *  - we received an intermediate status
 708          *  - fast notification was requested (primary status)
 709          *  - unsolicited interrupts
 710          */
 711         stctl = scsw_stctl(&cdev->private->irb.scsw);
 712         ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
 713                 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
 714                 (stctl == SCSW_STCTL_STATUS_PEND);
 715         if (!ending_status &&
 716             !cdev->private->options.repall &&
 717             !(stctl & SCSW_STCTL_INTER_STATUS) &&
 718             !(cdev->private->options.fast &&
 719               (stctl & SCSW_STCTL_PRIM_STATUS)))
 720                 return 0;
 721
 722         if (ending_status)
 723                 ccw_device_set_timeout(cdev, 0);
 724
 725         if (cdev->handler)
 726                 cdev->handler(cdev, cdev->private->intparm,
 727                               &cdev->private->irb);
 728
 729         memset(&cdev->private->irb, 0, sizeof(struct irb));
 730         return 1;
 731 }
 732
 733 /*
 734  * Got an interrupt for a normal io (state online).
 735  */
 736 static void
 737 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 738 {
 739         struct irb *irb;
 740         int is_cmd;
 741
 742         irb = this_cpu_ptr(&cio_irb);
 743         is_cmd = !scsw_is_tm(&irb->scsw);
 744         /* Check for unsolicited interrupt. */
 745         if (!scsw_is_solicited(&irb->scsw)) {
 746                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
 747                     !irb->esw.esw0.erw.cons) {
 748                         /* Unit check but no sense data. Need basic sense. */
 749                         if (ccw_device_do_sense(cdev, irb) != 0)
 750                                 goto call_handler_unsol;
 751                         memcpy(&cdev->private->irb, irb, sizeof(struct irb));
 752                         cdev->private->state = DEV_STATE_W4SENSE;
 753                         cdev->private->intparm = 0;
 754                         return;
 755                 }
 756 call_handler_unsol:
 757                 if (cdev->handler)
 758                         cdev->handler (cdev, 0, irb);
 759                 if (cdev->private->flags.doverify)
 760                         ccw_device_online_verify(cdev, 0);
 761                 return;
 762         }
 763         /* Accumulate status and find out if a basic sense is needed. */
 764         ccw_device_accumulate_irb(cdev, irb);
 765         if (is_cmd && cdev->private->flags.dosense) {
 766                 if (ccw_device_do_sense(cdev, irb) == 0) {
 767                         cdev->private->state = DEV_STATE_W4SENSE;
 768                 }
 769                 return;
 770         }
 771         /* Call the handler. */
 772         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 773                 /* Start delayed path verification. */
 774                 ccw_device_online_verify(cdev, 0);
 775 }
 776
 777 /*
 778  * Got an timeout in online state.
 779  */
 780 static void
 781 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 782 {
 783         int ret;
 784
 785         ccw_device_set_timeout(cdev, 0);
 786         cdev->private->iretry = 255;
 787         ret = ccw_device_cancel_halt_clear(cdev);
 788         if (ret == -EBUSY) {
 789                 ccw_device_set_timeout(cdev, 3*HZ);
 790                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 791                 return;
 792         }
 793         if (ret)
 794                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 795         else if (cdev->handler)
 796                 cdev->handler(cdev, cdev->private->intparm,
 797                               ERR_PTR(-ETIMEDOUT));
 798 }
 799
 800 /*
 801  * Got an interrupt for a basic sense.
 802  */
 803 static void
 804 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 805 {
 806         struct irb *irb;
 807
 808         irb = this_cpu_ptr(&cio_irb);
 809         /* Check for unsolicited interrupt. */
 810         if (scsw_stctl(&irb->scsw) ==
 811             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 812                 if (scsw_cc(&irb->scsw) == 1)
 813                         /* Basic sense hasn't started. Try again. */
 814                         ccw_device_do_sense(cdev, irb);
 815                 else {
 816                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
 817                                       "interrupt during w4sense...\n",
 818                                       cdev->private->dev_id.ssid,
 819                                       cdev->private->dev_id.devno);
 820                         if (cdev->handler)
 821                                 cdev->handler (cdev, 0, irb);
 822                 }
 823                 return;
 824         }
 825         /*
 826          * Check if a halt or clear has been issued in the meanwhile. If yes,
 827          * only deliver the halt/clear interrupt to the device driver as if it
 828          * had killed the original request.
 829          */
 830         if (scsw_fctl(&irb->scsw) &
 831             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
 832                 cdev->private->flags.dosense = 0;
 833                 memset(&cdev->private->irb, 0, sizeof(struct irb));
 834                 ccw_device_accumulate_irb(cdev, irb);
 835                 goto call_handler;
 836         }
 837         /* Add basic sense info to irb. */
 838         ccw_device_accumulate_basic_sense(cdev, irb);
 839         if (cdev->private->flags.dosense) {
 840                 /* Another basic sense is needed. */
 841                 ccw_device_do_sense(cdev, irb);
 842                 return;
 843         }
 844 call_handler:
 845         cdev->private->state = DEV_STATE_ONLINE;
 846         /* In case sensing interfered with setting the device online */
 847         wake_up(&cdev->private->wait_q);
 848         /* Call the handler. */
 849         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 850                 /* Start delayed path verification. */
 851                 ccw_device_online_verify(cdev, 0);
 852 }
 853
 854 static void
 855 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 856 {
 857         ccw_device_set_timeout(cdev, 0);
 858         /* Start delayed path verification. */
 859         ccw_device_online_verify(cdev, 0);
 860         /* OK, i/o is dead now. Call interrupt handler. */
 861         if (cdev->handler)
 862                 cdev->handler(cdev, cdev->private->intparm,
 863                               ERR_PTR(-EIO));
 864 }
 865
 866 static void
 867 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 868 {
 869         int ret;
 870
 871         ret = ccw_device_cancel_halt_clear(cdev);
 872         if (ret == -EBUSY) {
 873                 ccw_device_set_timeout(cdev, 3*HZ);
 874                 return;
 875         }
 876         /* Start delayed path verification. */
 877         ccw_device_online_verify(cdev, 0);
 878         if (cdev->handler)
 879                 cdev->handler(cdev, cdev->private->intparm,
 880                               ERR_PTR(-EIO));
 881 }
 882
 883 void ccw_device_kill_io(struct ccw_device *cdev)
 884 {
 885         int ret;
 886
 887         cdev->private->iretry = 255;
 888         ret = ccw_device_cancel_halt_clear(cdev);
 889         if (ret == -EBUSY) {
 890                 ccw_device_set_timeout(cdev, 3*HZ);
 891                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 892                 return;
 893         }
 894         /* Start delayed path verification. */
 895         ccw_device_online_verify(cdev, 0);
 896         if (cdev->handler)
 897                 cdev->handler(cdev, cdev->private->intparm,
 898                               ERR_PTR(-EIO));
 899 }
 900
 901 static void
 902 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 903 {
 904         /* Start verification after current task finished. */
 905         cdev->private->flags.doverify = 1;
 906 }
 907
 908 static void
 909 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 910 {
 911         struct subchannel *sch;
 912
 913         sch = to_subchannel(cdev->dev.parent);
 914         if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0)
 915                 /* Couldn't enable the subchannel for i/o. Sick device. */
 916                 return;
 917         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 918         ccw_device_sense_id_start(cdev);
 919 }
 920
 921 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
 922 {
 923         struct subchannel *sch;
 924
 925         if (cdev->private->state != DEV_STATE_DISCONNECTED)
 926                 return;
 927
 928         sch = to_subchannel(cdev->dev.parent);
 929         /* Update some values. */
 930         if (cio_update_schib(sch))
 931                 return;
 932         /*
 933          * The pim, pam, pom values may not be accurate, but they are the best
 934          * we have before performing device selection :/
 935          */
 936         sch->lpm = sch->schib.pmcw.pam & sch->opm;
 937         /*
 938          * Use the initial configuration since we can't be shure that the old
 939          * paths are valid.
 940          */
 941         io_subchannel_init_config(sch);
 942         if (cio_commit_config(sch))
 943                 return;
 944
 945         /* We should also udate ssd info, but this has to wait. */
 946         /* Check if this is another device which appeared on the same sch. */
 947         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
 948                 css_schedule_eval(sch->schid);
 949         else
 950                 ccw_device_start_id(cdev, 0);
 951 }
 952
 953 static void ccw_device_disabled_irq(struct ccw_device *cdev,
 954                                     enum dev_event dev_event)
 955 {
 956         struct subchannel *sch;
 957
 958         sch = to_subchannel(cdev->dev.parent);
 959         /*
 960          * An interrupt in a disabled state means a previous disable was not
 961          * successful - should not happen, but we try to disable again.
 962          */
 963         cio_disable_subchannel(sch);
 964 }
 965
 966 static void
 967 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
 968 {
 969         retry_set_schib(cdev);
 970         cdev->private->state = DEV_STATE_ONLINE;
 971         dev_fsm_event(cdev, dev_event);
 972 }
 973
 974 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
 975                                        enum dev_event dev_event)
 976 {
 977         cmf_retry_copy_block(cdev);
 978         cdev->private->state = DEV_STATE_ONLINE;
 979         dev_fsm_event(cdev, dev_event);
 980 }
 981
 982 static void
 983 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
 984 {
 985         ccw_device_set_timeout(cdev, 0);
 986         cdev->private->state = DEV_STATE_NOT_OPER;
 987         wake_up(&cdev->private->wait_q);
 988 }
 989
 990 static void
 991 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 992 {
 993         int ret;
 994
 995         ret = ccw_device_cancel_halt_clear(cdev);
 996         if (ret == -EBUSY) {
 997                 ccw_device_set_timeout(cdev, HZ/10);
 998         } else {
 999                 cdev->private->state = DEV_STATE_NOT_OPER;
1000                 wake_up(&cdev->private->wait_q);
1001         }
1002 }
1003
1004 /*
1005  * No operation action. This is used e.g. to ignore a timeout event in
1006  * state offline.
1007  */
1008 static void
1009 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1010 {
1011 }
1012
1013 /*
1014  * device statemachine
1015  */
1016 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1017         [DEV_STATE_NOT_OPER] = {
1018                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1019                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1020                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1021                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1022         },
1023         [DEV_STATE_SENSE_ID] = {
1024                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1025                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1026                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1027                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1028         },
1029         [DEV_STATE_OFFLINE] = {
1030                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1031                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1032                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1033                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
1034         },
1035         [DEV_STATE_VERIFY] = {
1036                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1037                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1038                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1039                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
1040         },
1041         [DEV_STATE_ONLINE] = {
1042                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1043                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1044                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1045                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1046         },
1047         [DEV_STATE_W4SENSE] = {
1048                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1049                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1050                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1051                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1052         },
1053         [DEV_STATE_DISBAND_PGID] = {
1054                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1055                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1056                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1057                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1058         },
1059         [DEV_STATE_BOXED] = {
1060                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1061                 [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
1062                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1063                 [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
1064         },
1065         /* states to wait for i/o completion before doing something */
1066         [DEV_STATE_TIMEOUT_KILL] = {
1067                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1068                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1069                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1070                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1071         },
1072         [DEV_STATE_QUIESCE] = {
1073                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1074                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1075                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1076                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1077         },
1078         /* special states for devices gone not operational */
1079         [DEV_STATE_DISCONNECTED] = {
1080                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1081                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1082                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1083                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1084         },
1085         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1086                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1087                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1088                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1089                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1090         },
1091         [DEV_STATE_CMFCHANGE] = {
1092                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1093                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1094                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1095                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1096         },
1097         [DEV_STATE_CMFUPDATE] = {
1098                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1099                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1100                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1101                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1102         },
1103         [DEV_STATE_STEAL_LOCK] = {
1104                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1105                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1106                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1107                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1108         },
1109 };
1110
1111 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);