drivers/s390/cio/device_fsm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * finite state machine for device handling
   4  *
   5  *    Copyright IBM Corp. 2002, 2008
   6  *    Author(s): Cornelia Huck ([email protected])
   7  *               Martin Schwidefsky ([email protected])
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/io.h>
  13 #include <linux/jiffies.h>
  14 #include <linux/string.h>
  15
  16 #include <asm/ccwdev.h>
  17 #include <asm/cio.h>
  18 #include <asm/chpid.h>
  19
  20 #include "cio.h"
  21 #include "cio_debug.h"
  22 #include "css.h"
  23 #include "device.h"
  24 #include "chsc.h"
  25 #include "ioasm.h"
  26 #include "chp.h"
  27
  28 static int timeout_log_enabled;
  29
  30 static int __init ccw_timeout_log_setup(char *unused)
  31 {
  32         timeout_log_enabled = 1;
  33         return 1;
  34 }
  35
  36 __setup("ccw_timeout_log", ccw_timeout_log_setup);
  37
  38 static void ccw_timeout_log(struct ccw_device *cdev)
  39 {
  40         struct schib schib;
  41         struct subchannel *sch;
  42         struct io_subchannel_private *private;
  43         union orb *orb;
  44         int cc;
  45
  46         sch = to_subchannel(cdev->dev.parent);
  47         private = to_io_private(sch);
  48         orb = &private->orb;
  49         cc = stsch(sch->schid, &schib);
  50
  51         printk(KERN_WARNING "cio: ccw device timeout occurred at %lx, "
  52                "device information:\n", get_tod_clock());
  53         printk(KERN_WARNING "cio: orb:\n");
  54         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  55                        orb, sizeof(*orb), 0);
  56         printk(KERN_WARNING "cio: ccw device bus id: %s\n",
  57                dev_name(&cdev->dev));
  58         printk(KERN_WARNING "cio: subchannel bus id: %s\n",
  59                dev_name(&sch->dev));
  60         printk(KERN_WARNING "cio: subchannel lpm: %02x, opm: %02x, "
  61                "vpm: %02x\n", sch->lpm, sch->opm, sch->vpm);
  62
  63         if (orb->tm.b) {
  64                 printk(KERN_WARNING "cio: orb indicates transport mode\n");
  65                 printk(KERN_WARNING "cio: last tcw:\n");
  66                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  67                                phys_to_virt(orb->tm.tcw),
  68                                sizeof(struct tcw), 0);
  69         } else {
  70                 printk(KERN_WARNING "cio: orb indicates command mode\n");
  71                 if ((void *)(addr_t)orb->cmd.cpa ==
  72                     &private->dma_area->sense_ccw ||
  73                     (void *)(addr_t)orb->cmd.cpa ==
  74                     cdev->private->dma_area->iccws)
  75                         printk(KERN_WARNING "cio: last channel program "
  76                                "(intern):\n");
  77                 else
  78                         printk(KERN_WARNING "cio: last channel program:\n");
  79
  80                 print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  81                                phys_to_virt(orb->cmd.cpa),
  82                                sizeof(struct ccw1), 0);
  83         }
  84         printk(KERN_WARNING "cio: ccw device state: %d\n",
  85                cdev->private->state);
  86         printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc);
  87         printk(KERN_WARNING "cio: schib:\n");
  88         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  89                        &schib, sizeof(schib), 0);
  90         printk(KERN_WARNING "cio: ccw device flags:\n");
  91         print_hex_dump(KERN_WARNING, "cio:  ", DUMP_PREFIX_NONE, 16, 1,
  92                        &cdev->private->flags, sizeof(cdev->private->flags), 0);
  93 }
  94
  95 /*
  96  * Timeout function. It just triggers a DEV_EVENT_TIMEOUT.
  97  */
  98 void
  99 ccw_device_timeout(struct timer_list *t)
 100 {
 101         struct ccw_device_private *priv = from_timer(priv, t, timer);
 102         struct ccw_device *cdev = priv->cdev;
 103
 104         spin_lock_irq(cdev->ccwlock);
 105         if (timeout_log_enabled)
 106                 ccw_timeout_log(cdev);
 107         dev_fsm_event(cdev, DEV_EVENT_TIMEOUT);
 108         spin_unlock_irq(cdev->ccwlock);
 109 }
 110
 111 /*
 112  * Set timeout
 113  */
 114 void
 115 ccw_device_set_timeout(struct ccw_device *cdev, int expires)
 116 {
 117         if (expires == 0)
 118                 del_timer(&cdev->private->timer);
 119         else
 120                 mod_timer(&cdev->private->timer, jiffies + expires);
 121 }
 122
 123 int
 124 ccw_device_cancel_halt_clear(struct ccw_device *cdev)
 125 {
 126         struct subchannel *sch;
 127         int ret;
 128
 129         sch = to_subchannel(cdev->dev.parent);
 130         ret = cio_cancel_halt_clear(sch, &cdev->private->iretry);
 131
 132         if (ret == -EIO)
 133                 CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n",
 134                               cdev->private->dev_id.ssid,
 135                               cdev->private->dev_id.devno);
 136
 137         return ret;
 138 }
 139
 140 void ccw_device_update_sense_data(struct ccw_device *cdev)
 141 {
 142         memset(&cdev->id, 0, sizeof(cdev->id));
 143         cdev->id.cu_type = cdev->private->dma_area->senseid.cu_type;
 144         cdev->id.cu_model = cdev->private->dma_area->senseid.cu_model;
 145         cdev->id.dev_type = cdev->private->dma_area->senseid.dev_type;
 146         cdev->id.dev_model = cdev->private->dma_area->senseid.dev_model;
 147 }
 148
 149 int ccw_device_test_sense_data(struct ccw_device *cdev)
 150 {
 151         return cdev->id.cu_type ==
 152                 cdev->private->dma_area->senseid.cu_type &&
 153                 cdev->id.cu_model ==
 154                 cdev->private->dma_area->senseid.cu_model &&
 155                 cdev->id.dev_type ==
 156                 cdev->private->dma_area->senseid.dev_type &&
 157                 cdev->id.dev_model ==
 158                 cdev->private->dma_area->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         switch (state) {
 223         case DEV_STATE_NOT_OPER:
 224                 break;
 225         case DEV_STATE_OFFLINE:
 226                 if (!cdev->online) {
 227                         ccw_device_update_sense_data(cdev);
 228                         break;
 229                 }
 230                 cdev->private->state = DEV_STATE_OFFLINE;
 231                 cdev->private->flags.recog_done = 1;
 232                 if (ccw_device_test_sense_data(cdev)) {
 233                         cdev->private->flags.donotify = 1;
 234                         ccw_device_online(cdev);
 235                         wake_up(&cdev->private->wait_q);
 236                 } else {
 237                         ccw_device_update_sense_data(cdev);
 238                         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 239                 }
 240                 return;
 241         case DEV_STATE_BOXED:
 242                 if (cdev->id.cu_type != 0) { /* device was recognized before */
 243                         cdev->private->flags.recog_done = 1;
 244                         cdev->private->state = DEV_STATE_BOXED;
 245                         wake_up(&cdev->private->wait_q);
 246                         return;
 247                 }
 248                 break;
 249         }
 250         cdev->private->state = state;
 251         io_subchannel_recog_done(cdev);
 252         wake_up(&cdev->private->wait_q);
 253 }
 254
 255 /*
 256  * Function called from device_id.c after sense id has completed.
 257  */
 258 void
 259 ccw_device_sense_id_done(struct ccw_device *cdev, int err)
 260 {
 261         switch (err) {
 262         case 0:
 263                 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE);
 264                 break;
 265         case -ETIME:            /* Sense id stopped by timeout. */
 266                 ccw_device_recog_done(cdev, DEV_STATE_BOXED);
 267                 break;
 268         default:
 269                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 270                 break;
 271         }
 272 }
 273
 274 /**
 275   * ccw_device_notify() - inform the device's driver about an event
 276   * @cdev: device for which an event occurred
 277   * @event: event that occurred
 278   *
 279   * Returns:
 280   *   -%EINVAL if the device is offline or has no driver.
 281   *   -%EOPNOTSUPP if the device's driver has no notifier registered.
 282   *   %NOTIFY_OK if the driver wants to keep the device.
 283   *   %NOTIFY_BAD if the driver doesn't want to keep the device.
 284   */
 285 int ccw_device_notify(struct ccw_device *cdev, int event)
 286 {
 287         int ret = -EINVAL;
 288
 289         if (!cdev->drv)
 290                 goto out;
 291         if (!cdev->online)
 292                 goto out;
 293         CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n",
 294                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
 295                       event);
 296         if (!cdev->drv->notify) {
 297                 ret = -EOPNOTSUPP;
 298                 goto out;
 299         }
 300         if (cdev->drv->notify(cdev, event))
 301                 ret = NOTIFY_OK;
 302         else
 303                 ret = NOTIFY_BAD;
 304 out:
 305         return ret;
 306 }
 307
 308 static void ccw_device_oper_notify(struct ccw_device *cdev)
 309 {
 310         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 311
 312         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) {
 313                 /* Re-enable channel measurements, if needed. */
 314                 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF);
 315                 /* Save indication for new paths. */
 316                 cdev->private->path_new_mask = sch->vpm;
 317                 return;
 318         }
 319         /* Driver doesn't want device back. */
 320         ccw_device_set_notoper(cdev);
 321         ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
 322 }
 323
 324 /*
 325  * Finished with online/offline processing.
 326  */
 327 static void
 328 ccw_device_done(struct ccw_device *cdev, int state)
 329 {
 330         struct subchannel *sch;
 331
 332         sch = to_subchannel(cdev->dev.parent);
 333
 334         ccw_device_set_timeout(cdev, 0);
 335
 336         if (state != DEV_STATE_ONLINE)
 337                 cio_disable_subchannel(sch);
 338
 339         /* Reset device status. */
 340         memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
 341
 342         cdev->private->state = state;
 343
 344         switch (state) {
 345         case DEV_STATE_BOXED:
 346                 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n",
 347                               cdev->private->dev_id.devno, sch->schid.sch_no);
 348                 if (cdev->online &&
 349                     ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK)
 350                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 351                 cdev->private->flags.donotify = 0;
 352                 break;
 353         case DEV_STATE_NOT_OPER:
 354                 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n",
 355                               cdev->private->dev_id.devno, sch->schid.sch_no);
 356                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 357                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 358                 else
 359                         ccw_device_set_disconnected(cdev);
 360                 cdev->private->flags.donotify = 0;
 361                 break;
 362         case DEV_STATE_DISCONNECTED:
 363                 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel "
 364                               "%04x\n", cdev->private->dev_id.devno,
 365                               sch->schid.sch_no);
 366                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) {
 367                         cdev->private->state = DEV_STATE_NOT_OPER;
 368                         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 369                 } else
 370                         ccw_device_set_disconnected(cdev);
 371                 cdev->private->flags.donotify = 0;
 372                 break;
 373         default:
 374                 break;
 375         }
 376
 377         if (cdev->private->flags.donotify) {
 378                 cdev->private->flags.donotify = 0;
 379                 ccw_device_oper_notify(cdev);
 380         }
 381         wake_up(&cdev->private->wait_q);
 382 }
 383
 384 /*
 385  * Start device recognition.
 386  */
 387 void ccw_device_recognition(struct ccw_device *cdev)
 388 {
 389         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 390
 391         /*
 392          * We used to start here with a sense pgid to find out whether a device
 393          * is locked by someone else. Unfortunately, the sense pgid command
 394          * code has other meanings on devices predating the path grouping
 395          * algorithm, so we start with sense id and box the device after an
 396          * timeout (or if sense pgid during path verification detects the device
 397          * is locked, as may happen on newer devices).
 398          */
 399         cdev->private->flags.recog_done = 0;
 400         cdev->private->state = DEV_STATE_SENSE_ID;
 401         if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch))) {
 402                 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER);
 403                 return;
 404         }
 405         ccw_device_sense_id_start(cdev);
 406 }
 407
 408 /*
 409  * Handle events for states that use the ccw request infrastructure.
 410  */
 411 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e)
 412 {
 413         switch (e) {
 414         case DEV_EVENT_NOTOPER:
 415                 ccw_request_notoper(cdev);
 416                 break;
 417         case DEV_EVENT_INTERRUPT:
 418                 ccw_request_handler(cdev);
 419                 break;
 420         case DEV_EVENT_TIMEOUT:
 421                 ccw_request_timeout(cdev);
 422                 break;
 423         default:
 424                 break;
 425         }
 426 }
 427
 428 static void ccw_device_report_path_events(struct ccw_device *cdev)
 429 {
 430         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 431         int path_event[8];
 432         int chp, mask;
 433
 434         for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) {
 435                 path_event[chp] = PE_NONE;
 436                 if (mask & cdev->private->path_gone_mask & ~(sch->vpm))
 437                         path_event[chp] |= PE_PATH_GONE;
 438                 if (mask & cdev->private->path_new_mask & sch->vpm)
 439                         path_event[chp] |= PE_PATH_AVAILABLE;
 440                 if (mask & cdev->private->pgid_reset_mask & sch->vpm)
 441                         path_event[chp] |= PE_PATHGROUP_ESTABLISHED;
 442         }
 443         if (cdev->online && cdev->drv->path_event)
 444                 cdev->drv->path_event(cdev, path_event);
 445 }
 446
 447 static void ccw_device_reset_path_events(struct ccw_device *cdev)
 448 {
 449         cdev->private->path_gone_mask = 0;
 450         cdev->private->path_new_mask = 0;
 451         cdev->private->pgid_reset_mask = 0;
 452 }
 453
 454 static void create_fake_irb(struct irb *irb, int type)
 455 {
 456         memset(irb, 0, sizeof(*irb));
 457         if (type == FAKE_CMD_IRB) {
 458                 struct cmd_scsw *scsw = &irb->scsw.cmd;
 459                 scsw->cc = 1;
 460                 scsw->fctl = SCSW_FCTL_START_FUNC;
 461                 scsw->actl = SCSW_ACTL_START_PEND;
 462                 scsw->stctl = SCSW_STCTL_STATUS_PEND;
 463         } else if (type == FAKE_TM_IRB) {
 464                 struct tm_scsw *scsw = &irb->scsw.tm;
 465                 scsw->x = 1;
 466                 scsw->cc = 1;
 467                 scsw->fctl = SCSW_FCTL_START_FUNC;
 468                 scsw->actl = SCSW_ACTL_START_PEND;
 469                 scsw->stctl = SCSW_STCTL_STATUS_PEND;
 470         }
 471 }
 472
 473 static void ccw_device_handle_broken_paths(struct ccw_device *cdev)
 474 {
 475         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 476         u8 broken_paths = (sch->schib.pmcw.pam & sch->opm) ^ sch->vpm;
 477
 478         if (broken_paths && (cdev->private->path_broken_mask != broken_paths))
 479                 ccw_device_schedule_recovery();
 480
 481         cdev->private->path_broken_mask = broken_paths;
 482 }
 483
 484 void ccw_device_verify_done(struct ccw_device *cdev, int err)
 485 {
 486         struct subchannel *sch;
 487
 488         sch = to_subchannel(cdev->dev.parent);
 489         /* Update schib - pom may have changed. */
 490         if (cio_update_schib(sch)) {
 491                 err = -ENODEV;
 492                 goto callback;
 493         }
 494         /* Update lpm with verified path mask. */
 495         sch->lpm = sch->vpm;
 496         /* Repeat path verification? */
 497         if (cdev->private->flags.doverify) {
 498                 ccw_device_verify_start(cdev);
 499                 return;
 500         }
 501 callback:
 502         switch (err) {
 503         case 0:
 504                 ccw_device_done(cdev, DEV_STATE_ONLINE);
 505                 /* Deliver fake irb to device driver, if needed. */
 506                 if (cdev->private->flags.fake_irb) {
 507                         create_fake_irb(&cdev->private->dma_area->irb,
 508                                         cdev->private->flags.fake_irb);
 509                         cdev->private->flags.fake_irb = 0;
 510                         if (cdev->handler)
 511                                 cdev->handler(cdev, cdev->private->intparm,
 512                                               &cdev->private->dma_area->irb);
 513                         memset(&cdev->private->dma_area->irb, 0,
 514                                sizeof(struct irb));
 515                 }
 516                 ccw_device_report_path_events(cdev);
 517                 ccw_device_handle_broken_paths(cdev);
 518                 break;
 519         case -ETIME:
 520         case -EUSERS:
 521                 /* Reset oper notify indication after verify error. */
 522                 cdev->private->flags.donotify = 0;
 523                 ccw_device_done(cdev, DEV_STATE_BOXED);
 524                 break;
 525         case -EACCES:
 526                 /* Reset oper notify indication after verify error. */
 527                 cdev->private->flags.donotify = 0;
 528                 ccw_device_done(cdev, DEV_STATE_DISCONNECTED);
 529                 break;
 530         default:
 531                 /* Reset oper notify indication after verify error. */
 532                 cdev->private->flags.donotify = 0;
 533                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 534                 break;
 535         }
 536         ccw_device_reset_path_events(cdev);
 537 }
 538
 539 /*
 540  * Get device online.
 541  */
 542 int
 543 ccw_device_online(struct ccw_device *cdev)
 544 {
 545         struct subchannel *sch;
 546         int ret;
 547
 548         if ((cdev->private->state != DEV_STATE_OFFLINE) &&
 549             (cdev->private->state != DEV_STATE_BOXED))
 550                 return -EINVAL;
 551         sch = to_subchannel(cdev->dev.parent);
 552         ret = cio_enable_subchannel(sch, (u32)virt_to_phys(sch));
 553         if (ret != 0) {
 554                 /* Couldn't enable the subchannel for i/o. Sick device. */
 555                 if (ret == -ENODEV)
 556                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 557                 return ret;
 558         }
 559         /* Start initial path verification. */
 560         cdev->private->state = DEV_STATE_VERIFY;
 561         ccw_device_verify_start(cdev);
 562         return 0;
 563 }
 564
 565 void
 566 ccw_device_disband_done(struct ccw_device *cdev, int err)
 567 {
 568         switch (err) {
 569         case 0:
 570                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 571                 break;
 572         case -ETIME:
 573                 ccw_device_done(cdev, DEV_STATE_BOXED);
 574                 break;
 575         default:
 576                 cdev->private->flags.donotify = 0;
 577                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 578                 break;
 579         }
 580 }
 581
 582 /*
 583  * Shutdown device.
 584  */
 585 int
 586 ccw_device_offline(struct ccw_device *cdev)
 587 {
 588         struct subchannel *sch;
 589
 590         /* Allow ccw_device_offline while disconnected. */
 591         if (cdev->private->state == DEV_STATE_DISCONNECTED ||
 592             cdev->private->state == DEV_STATE_NOT_OPER) {
 593                 cdev->private->flags.donotify = 0;
 594                 ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 595                 return 0;
 596         }
 597         if (cdev->private->state == DEV_STATE_BOXED) {
 598                 ccw_device_done(cdev, DEV_STATE_BOXED);
 599                 return 0;
 600         }
 601         if (ccw_device_is_orphan(cdev)) {
 602                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 603                 return 0;
 604         }
 605         sch = to_subchannel(cdev->dev.parent);
 606         if (cio_update_schib(sch))
 607                 return -ENODEV;
 608         if (scsw_actl(&sch->schib.scsw) != 0)
 609                 return -EBUSY;
 610         if (cdev->private->state != DEV_STATE_ONLINE)
 611                 return -EINVAL;
 612         /* Are we doing path grouping? */
 613         if (!cdev->private->flags.pgroup) {
 614                 /* No, set state offline immediately. */
 615                 ccw_device_done(cdev, DEV_STATE_OFFLINE);
 616                 return 0;
 617         }
 618         /* Start Set Path Group commands. */
 619         cdev->private->state = DEV_STATE_DISBAND_PGID;
 620         ccw_device_disband_start(cdev);
 621         return 0;
 622 }
 623
 624 /*
 625  * Handle not operational event in non-special state.
 626  */
 627 static void ccw_device_generic_notoper(struct ccw_device *cdev,
 628                                        enum dev_event dev_event)
 629 {
 630         if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
 631                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 632         else
 633                 ccw_device_set_disconnected(cdev);
 634 }
 635
 636 /*
 637  * Handle path verification event in offline state.
 638  */
 639 static void ccw_device_offline_verify(struct ccw_device *cdev,
 640                                       enum dev_event dev_event)
 641 {
 642         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 643
 644         css_schedule_eval(sch->schid);
 645 }
 646
 647 /*
 648  * Handle path verification event.
 649  */
 650 static void
 651 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event)
 652 {
 653         struct subchannel *sch;
 654
 655         if (cdev->private->state == DEV_STATE_W4SENSE) {
 656                 cdev->private->flags.doverify = 1;
 657                 return;
 658         }
 659         sch = to_subchannel(cdev->dev.parent);
 660         /*
 661          * Since we might not just be coming from an interrupt from the
 662          * subchannel we have to update the schib.
 663          */
 664         if (cio_update_schib(sch)) {
 665                 ccw_device_verify_done(cdev, -ENODEV);
 666                 return;
 667         }
 668
 669         if (scsw_actl(&sch->schib.scsw) != 0 ||
 670             (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) ||
 671             (scsw_stctl(&cdev->private->dma_area->irb.scsw) &
 672              SCSW_STCTL_STATUS_PEND)) {
 673                 /*
 674                  * No final status yet or final status not yet delivered
 675                  * to the device driver. Can't do path verification now,
 676                  * delay until final status was delivered.
 677                  */
 678                 cdev->private->flags.doverify = 1;
 679                 return;
 680         }
 681         /* Device is idle, we can do the path verification. */
 682         cdev->private->state = DEV_STATE_VERIFY;
 683         ccw_device_verify_start(cdev);
 684 }
 685
 686 /*
 687  * Handle path verification event in boxed state.
 688  */
 689 static void ccw_device_boxed_verify(struct ccw_device *cdev,
 690                                     enum dev_event dev_event)
 691 {
 692         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 693
 694         if (cdev->online) {
 695                 if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)))
 696                         ccw_device_done(cdev, DEV_STATE_NOT_OPER);
 697                 else
 698                         ccw_device_online_verify(cdev, dev_event);
 699         } else
 700                 css_schedule_eval(sch->schid);
 701 }
 702
 703 /*
 704  * Pass interrupt to device driver.
 705  */
 706 static int ccw_device_call_handler(struct ccw_device *cdev)
 707 {
 708         unsigned int stctl;
 709         int ending_status;
 710
 711         /*
 712          * we allow for the device action handler if .
 713          *  - we received ending status
 714          *  - the action handler requested to see all interrupts
 715          *  - we received an intermediate status
 716          *  - fast notification was requested (primary status)
 717          *  - unsolicited interrupts
 718          */
 719         stctl = scsw_stctl(&cdev->private->dma_area->irb.scsw);
 720         ending_status = (stctl & SCSW_STCTL_SEC_STATUS) ||
 721                 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) ||
 722                 (stctl == SCSW_STCTL_STATUS_PEND);
 723         if (!ending_status &&
 724             !cdev->private->options.repall &&
 725             !(stctl & SCSW_STCTL_INTER_STATUS) &&
 726             !(cdev->private->options.fast &&
 727               (stctl & SCSW_STCTL_PRIM_STATUS)))
 728                 return 0;
 729
 730         if (ending_status)
 731                 ccw_device_set_timeout(cdev, 0);
 732
 733         if (cdev->handler)
 734                 cdev->handler(cdev, cdev->private->intparm,
 735                               &cdev->private->dma_area->irb);
 736
 737         memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
 738         return 1;
 739 }
 740
 741 /*
 742  * Got an interrupt for a normal io (state online).
 743  */
 744 static void
 745 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event)
 746 {
 747         struct irb *irb;
 748         int is_cmd;
 749
 750         irb = this_cpu_ptr(&cio_irb);
 751         is_cmd = !scsw_is_tm(&irb->scsw);
 752         /* Check for unsolicited interrupt. */
 753         if (!scsw_is_solicited(&irb->scsw)) {
 754                 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) &&
 755                     !irb->esw.esw0.erw.cons) {
 756                         /* Unit check but no sense data. Need basic sense. */
 757                         if (ccw_device_do_sense(cdev, irb) != 0)
 758                                 goto call_handler_unsol;
 759                         memcpy(&cdev->private->dma_area->irb, irb,
 760                                sizeof(struct irb));
 761                         cdev->private->state = DEV_STATE_W4SENSE;
 762                         cdev->private->intparm = 0;
 763                         return;
 764                 }
 765 call_handler_unsol:
 766                 if (cdev->handler)
 767                         cdev->handler (cdev, 0, irb);
 768                 if (cdev->private->flags.doverify)
 769                         ccw_device_online_verify(cdev, 0);
 770                 return;
 771         }
 772         /* Accumulate status and find out if a basic sense is needed. */
 773         ccw_device_accumulate_irb(cdev, irb);
 774         if (is_cmd && cdev->private->flags.dosense) {
 775                 if (ccw_device_do_sense(cdev, irb) == 0) {
 776                         cdev->private->state = DEV_STATE_W4SENSE;
 777                 }
 778                 return;
 779         }
 780         /* Call the handler. */
 781         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 782                 /* Start delayed path verification. */
 783                 ccw_device_online_verify(cdev, 0);
 784 }
 785
 786 /*
 787  * Got an timeout in online state.
 788  */
 789 static void
 790 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 791 {
 792         int ret;
 793
 794         ccw_device_set_timeout(cdev, 0);
 795         cdev->private->iretry = 255;
 796         cdev->private->async_kill_io_rc = -ETIMEDOUT;
 797         ret = ccw_device_cancel_halt_clear(cdev);
 798         if (ret == -EBUSY) {
 799                 ccw_device_set_timeout(cdev, 3*HZ);
 800                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 801                 return;
 802         }
 803         if (ret)
 804                 dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 805         else if (cdev->handler)
 806                 cdev->handler(cdev, cdev->private->intparm,
 807                               ERR_PTR(-ETIMEDOUT));
 808 }
 809
 810 /*
 811  * Got an interrupt for a basic sense.
 812  */
 813 static void
 814 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event)
 815 {
 816         struct irb *irb;
 817
 818         irb = this_cpu_ptr(&cio_irb);
 819         /* Check for unsolicited interrupt. */
 820         if (scsw_stctl(&irb->scsw) ==
 821             (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) {
 822                 if (scsw_cc(&irb->scsw) == 1)
 823                         /* Basic sense hasn't started. Try again. */
 824                         ccw_device_do_sense(cdev, irb);
 825                 else {
 826                         CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited "
 827                                       "interrupt during w4sense...\n",
 828                                       cdev->private->dev_id.ssid,
 829                                       cdev->private->dev_id.devno);
 830                         if (cdev->handler)
 831                                 cdev->handler (cdev, 0, irb);
 832                 }
 833                 return;
 834         }
 835         /*
 836          * Check if a halt or clear has been issued in the meanwhile. If yes,
 837          * only deliver the halt/clear interrupt to the device driver as if it
 838          * had killed the original request.
 839          */
 840         if (scsw_fctl(&irb->scsw) &
 841             (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) {
 842                 cdev->private->flags.dosense = 0;
 843                 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb));
 844                 ccw_device_accumulate_irb(cdev, irb);
 845                 goto call_handler;
 846         }
 847         /* Add basic sense info to irb. */
 848         ccw_device_accumulate_basic_sense(cdev, irb);
 849         if (cdev->private->flags.dosense) {
 850                 /* Another basic sense is needed. */
 851                 ccw_device_do_sense(cdev, irb);
 852                 return;
 853         }
 854 call_handler:
 855         cdev->private->state = DEV_STATE_ONLINE;
 856         /* In case sensing interfered with setting the device online */
 857         wake_up(&cdev->private->wait_q);
 858         /* Call the handler. */
 859         if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify)
 860                 /* Start delayed path verification. */
 861                 ccw_device_online_verify(cdev, 0);
 862 }
 863
 864 static void
 865 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event)
 866 {
 867         ccw_device_set_timeout(cdev, 0);
 868         /* Start delayed path verification. */
 869         ccw_device_online_verify(cdev, 0);
 870         /* OK, i/o is dead now. Call interrupt handler. */
 871         if (cdev->handler)
 872                 cdev->handler(cdev, cdev->private->intparm,
 873                               ERR_PTR(cdev->private->async_kill_io_rc));
 874 }
 875
 876 static void
 877 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event)
 878 {
 879         int ret;
 880
 881         ret = ccw_device_cancel_halt_clear(cdev);
 882         if (ret == -EBUSY) {
 883                 ccw_device_set_timeout(cdev, 3*HZ);
 884                 return;
 885         }
 886         /* Start delayed path verification. */
 887         ccw_device_online_verify(cdev, 0);
 888         if (cdev->handler)
 889                 cdev->handler(cdev, cdev->private->intparm,
 890                               ERR_PTR(cdev->private->async_kill_io_rc));
 891 }
 892
 893 void ccw_device_kill_io(struct ccw_device *cdev)
 894 {
 895         int ret;
 896
 897         ccw_device_set_timeout(cdev, 0);
 898         cdev->private->iretry = 255;
 899         cdev->private->async_kill_io_rc = -EIO;
 900         ret = ccw_device_cancel_halt_clear(cdev);
 901         if (ret == -EBUSY) {
 902                 ccw_device_set_timeout(cdev, 3*HZ);
 903                 cdev->private->state = DEV_STATE_TIMEOUT_KILL;
 904                 return;
 905         }
 906         /* Start delayed path verification. */
 907         ccw_device_online_verify(cdev, 0);
 908         if (cdev->handler)
 909                 cdev->handler(cdev, cdev->private->intparm,
 910                               ERR_PTR(-EIO));
 911 }
 912
 913 static void
 914 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event)
 915 {
 916         /* Start verification after current task finished. */
 917         cdev->private->flags.doverify = 1;
 918 }
 919
 920 static void
 921 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event)
 922 {
 923         struct subchannel *sch;
 924
 925         sch = to_subchannel(cdev->dev.parent);
 926         if (cio_enable_subchannel(sch, (u32)virt_to_phys(sch)) != 0)
 927                 /* Couldn't enable the subchannel for i/o. Sick device. */
 928                 return;
 929         cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID;
 930         ccw_device_sense_id_start(cdev);
 931 }
 932
 933 void ccw_device_trigger_reprobe(struct ccw_device *cdev)
 934 {
 935         struct subchannel *sch;
 936
 937         if (cdev->private->state != DEV_STATE_DISCONNECTED)
 938                 return;
 939
 940         sch = to_subchannel(cdev->dev.parent);
 941         /* Update some values. */
 942         if (cio_update_schib(sch))
 943                 return;
 944         /*
 945          * The pim, pam, pom values may not be accurate, but they are the best
 946          * we have before performing device selection :/
 947          */
 948         sch->lpm = sch->schib.pmcw.pam & sch->opm;
 949         /*
 950          * Use the initial configuration since we can't be sure that the old
 951          * paths are valid.
 952          */
 953         io_subchannel_init_config(sch);
 954         if (cio_commit_config(sch))
 955                 return;
 956
 957         /* We should also udate ssd info, but this has to wait. */
 958         /* Check if this is another device which appeared on the same sch. */
 959         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno)
 960                 css_schedule_eval(sch->schid);
 961         else
 962                 ccw_device_start_id(cdev, 0);
 963 }
 964
 965 static void ccw_device_disabled_irq(struct ccw_device *cdev,
 966                                     enum dev_event dev_event)
 967 {
 968         struct subchannel *sch;
 969
 970         sch = to_subchannel(cdev->dev.parent);
 971         /*
 972          * An interrupt in a disabled state means a previous disable was not
 973          * successful - should not happen, but we try to disable again.
 974          */
 975         cio_disable_subchannel(sch);
 976 }
 977
 978 static void
 979 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event)
 980 {
 981         retry_set_schib(cdev);
 982         cdev->private->state = DEV_STATE_ONLINE;
 983         dev_fsm_event(cdev, dev_event);
 984 }
 985
 986 static void ccw_device_update_cmfblock(struct ccw_device *cdev,
 987                                        enum dev_event dev_event)
 988 {
 989         cmf_retry_copy_block(cdev);
 990         cdev->private->state = DEV_STATE_ONLINE;
 991         dev_fsm_event(cdev, dev_event);
 992 }
 993
 994 static void
 995 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event)
 996 {
 997         ccw_device_set_timeout(cdev, 0);
 998         cdev->private->state = DEV_STATE_NOT_OPER;
 999         wake_up(&cdev->private->wait_q);
1000 }
1001
1002 static void
1003 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event)
1004 {
1005         int ret;
1006
1007         ret = ccw_device_cancel_halt_clear(cdev);
1008         if (ret == -EBUSY) {
1009                 ccw_device_set_timeout(cdev, HZ/10);
1010         } else {
1011                 cdev->private->state = DEV_STATE_NOT_OPER;
1012                 wake_up(&cdev->private->wait_q);
1013         }
1014 }
1015
1016 /*
1017  * No operation action. This is used e.g. to ignore a timeout event in
1018  * state offline.
1019  */
1020 static void
1021 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event)
1022 {
1023 }
1024
1025 /*
1026  * device statemachine
1027  */
1028 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = {
1029         [DEV_STATE_NOT_OPER] = {
1030                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1031                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1032                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1033                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1034         },
1035         [DEV_STATE_SENSE_ID] = {
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_nop,
1040         },
1041         [DEV_STATE_OFFLINE] = {
1042                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1043                 [DEV_EVENT_INTERRUPT]   = ccw_device_disabled_irq,
1044                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1045                 [DEV_EVENT_VERIFY]      = ccw_device_offline_verify,
1046         },
1047         [DEV_STATE_VERIFY] = {
1048                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1049                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1050                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1051                 [DEV_EVENT_VERIFY]      = ccw_device_delay_verify,
1052         },
1053         [DEV_STATE_ONLINE] = {
1054                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1055                 [DEV_EVENT_INTERRUPT]   = ccw_device_irq,
1056                 [DEV_EVENT_TIMEOUT]     = ccw_device_online_timeout,
1057                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1058         },
1059         [DEV_STATE_W4SENSE] = {
1060                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1061                 [DEV_EVENT_INTERRUPT]   = ccw_device_w4sense,
1062                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1063                 [DEV_EVENT_VERIFY]      = ccw_device_online_verify,
1064         },
1065         [DEV_STATE_DISBAND_PGID] = {
1066                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1067                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1068                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1069                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1070         },
1071         [DEV_STATE_BOXED] = {
1072                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1073                 [DEV_EVENT_INTERRUPT]   = ccw_device_nop,
1074                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1075                 [DEV_EVENT_VERIFY]      = ccw_device_boxed_verify,
1076         },
1077         /* states to wait for i/o completion before doing something */
1078         [DEV_STATE_TIMEOUT_KILL] = {
1079                 [DEV_EVENT_NOTOPER]     = ccw_device_generic_notoper,
1080                 [DEV_EVENT_INTERRUPT]   = ccw_device_killing_irq,
1081                 [DEV_EVENT_TIMEOUT]     = ccw_device_killing_timeout,
1082                 [DEV_EVENT_VERIFY]      = ccw_device_nop, //FIXME
1083         },
1084         [DEV_STATE_QUIESCE] = {
1085                 [DEV_EVENT_NOTOPER]     = ccw_device_quiesce_done,
1086                 [DEV_EVENT_INTERRUPT]   = ccw_device_quiesce_done,
1087                 [DEV_EVENT_TIMEOUT]     = ccw_device_quiesce_timeout,
1088                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1089         },
1090         /* special states for devices gone not operational */
1091         [DEV_STATE_DISCONNECTED] = {
1092                 [DEV_EVENT_NOTOPER]     = ccw_device_nop,
1093                 [DEV_EVENT_INTERRUPT]   = ccw_device_start_id,
1094                 [DEV_EVENT_TIMEOUT]     = ccw_device_nop,
1095                 [DEV_EVENT_VERIFY]      = ccw_device_start_id,
1096         },
1097         [DEV_STATE_DISCONNECTED_SENSE_ID] = {
1098                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1099                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1100                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1101                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1102         },
1103         [DEV_STATE_CMFCHANGE] = {
1104                 [DEV_EVENT_NOTOPER]     = ccw_device_change_cmfstate,
1105                 [DEV_EVENT_INTERRUPT]   = ccw_device_change_cmfstate,
1106                 [DEV_EVENT_TIMEOUT]     = ccw_device_change_cmfstate,
1107                 [DEV_EVENT_VERIFY]      = ccw_device_change_cmfstate,
1108         },
1109         [DEV_STATE_CMFUPDATE] = {
1110                 [DEV_EVENT_NOTOPER]     = ccw_device_update_cmfblock,
1111                 [DEV_EVENT_INTERRUPT]   = ccw_device_update_cmfblock,
1112                 [DEV_EVENT_TIMEOUT]     = ccw_device_update_cmfblock,
1113                 [DEV_EVENT_VERIFY]      = ccw_device_update_cmfblock,
1114         },
1115         [DEV_STATE_STEAL_LOCK] = {
1116                 [DEV_EVENT_NOTOPER]     = ccw_device_request_event,
1117                 [DEV_EVENT_INTERRUPT]   = ccw_device_request_event,
1118                 [DEV_EVENT_TIMEOUT]     = ccw_device_request_event,
1119                 [DEV_EVENT_VERIFY]      = ccw_device_nop,
1120         },
1121 };
1122
1123 EXPORT_SYMBOL_GPL(ccw_device_set_timeout);