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_err(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 /* Function was unsuccessful */ 178 CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n", 179 cdev->private->dev_id.ssid, cdev->private->dev_id.devno); 180 return -EIO; 181 } 182 183 void ccw_device_update_sense_data(struct ccw_device *cdev) 184 { 185 memset(&cdev->id, 0, sizeof(cdev->id)); 186 cdev->id.cu_type = cdev->private->senseid.cu_type; 187 cdev->id.cu_model = cdev->private->senseid.cu_model; 188 cdev->id.dev_type = cdev->private->senseid.dev_type; 189 cdev->id.dev_model = cdev->private->senseid.dev_model; 190 } 191 192 int ccw_device_test_sense_data(struct ccw_device *cdev) 193 { 194 return cdev->id.cu_type == cdev->private->senseid.cu_type && 195 cdev->id.cu_model == cdev->private->senseid.cu_model && 196 cdev->id.dev_type == cdev->private->senseid.dev_type && 197 cdev->id.dev_model == cdev->private->senseid.dev_model; 198 } 199 200 /* 201 * The machine won't give us any notification by machine check if a chpid has 202 * been varied online on the SE so we have to find out by magic (i. e. driving 203 * the channel subsystem to device selection and updating our path masks). 204 */ 205 static void 206 __recover_lost_chpids(struct subchannel *sch, int old_lpm) 207 { 208 int mask, i; 209 struct chp_id chpid; 210 211 chp_id_init(&chpid); 212 for (i = 0; i<8; i++) { 213 mask = 0x80 >> i; 214 if (!(sch->lpm & mask)) 215 continue; 216 if (old_lpm & mask) 217 continue; 218 chpid.id = sch->schib.pmcw.chpid[i]; 219 if (!chp_is_registered(chpid)) 220 css_schedule_eval_all(); 221 } 222 } 223 224 /* 225 * Stop device recognition. 226 */ 227 static void 228 ccw_device_recog_done(struct ccw_device *cdev, int state) 229 { 230 struct subchannel *sch; 231 int old_lpm; 232 233 sch = to_subchannel(cdev->dev.parent); 234 235 if (cio_disable_subchannel(sch)) 236 state = DEV_STATE_NOT_OPER; 237 /* 238 * Now that we tried recognition, we have performed device selection 239 * through ssch() and the path information is up to date. 240 */ 241 old_lpm = sch->lpm; 242 243 /* Check since device may again have become not operational. */ 244 if (cio_update_schib(sch)) 245 state = DEV_STATE_NOT_OPER; 246 else 247 sch->lpm = sch->schib.pmcw.pam & sch->opm; 248 249 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) 250 /* Force reprobe on all chpids. */ 251 old_lpm = 0; 252 if (sch->lpm != old_lpm) 253 __recover_lost_chpids(sch, old_lpm); 254 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID && 255 (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) { 256 cdev->private->flags.recog_done = 1; 257 cdev->private->state = DEV_STATE_DISCONNECTED; 258 wake_up(&cdev->private->wait_q); 259 return; 260 } 261 if (cdev->private->flags.resuming) { 262 cdev->private->state = state; 263 cdev->private->flags.recog_done = 1; 264 wake_up(&cdev->private->wait_q); 265 return; 266 } 267 switch (state) { 268 case DEV_STATE_NOT_OPER: 269 break; 270 case DEV_STATE_OFFLINE: 271 if (!cdev->online) { 272 ccw_device_update_sense_data(cdev); 273 break; 274 } 275 cdev->private->state = DEV_STATE_OFFLINE; 276 cdev->private->flags.recog_done = 1; 277 if (ccw_device_test_sense_data(cdev)) { 278 cdev->private->flags.donotify = 1; 279 ccw_device_online(cdev); 280 wake_up(&cdev->private->wait_q); 281 } else { 282 ccw_device_update_sense_data(cdev); 283 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND); 284 } 285 return; 286 case DEV_STATE_BOXED: 287 if (cdev->id.cu_type != 0) { /* device was recognized before */ 288 cdev->private->flags.recog_done = 1; 289 cdev->private->state = DEV_STATE_BOXED; 290 wake_up(&cdev->private->wait_q); 291 return; 292 } 293 break; 294 } 295 cdev->private->state = state; 296 io_subchannel_recog_done(cdev); 297 wake_up(&cdev->private->wait_q); 298 } 299 300 /* 301 * Function called from device_id.c after sense id has completed. 302 */ 303 void 304 ccw_device_sense_id_done(struct ccw_device *cdev, int err) 305 { 306 switch (err) { 307 case 0: 308 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE); 309 break; 310 case -ETIME: /* Sense id stopped by timeout. */ 311 ccw_device_recog_done(cdev, DEV_STATE_BOXED); 312 break; 313 default: 314 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER); 315 break; 316 } 317 } 318 319 /** 320 * ccw_device_notify() - inform the device's driver about an event 321 * @cdev: device for which an event occurred 322 * @event: event that occurred 323 * 324 * Returns: 325 * -%EINVAL if the device is offline or has no driver. 326 * -%EOPNOTSUPP if the device's driver has no notifier registered. 327 * %NOTIFY_OK if the driver wants to keep the device. 328 * %NOTIFY_BAD if the driver doesn't want to keep the device. 329 */ 330 int ccw_device_notify(struct ccw_device *cdev, int event) 331 { 332 int ret = -EINVAL; 333 334 if (!cdev->drv) 335 goto out; 336 if (!cdev->online) 337 goto out; 338 CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n", 339 cdev->private->dev_id.ssid, cdev->private->dev_id.devno, 340 event); 341 if (!cdev->drv->notify) { 342 ret = -EOPNOTSUPP; 343 goto out; 344 } 345 if (cdev->drv->notify(cdev, event)) 346 ret = NOTIFY_OK; 347 else 348 ret = NOTIFY_BAD; 349 out: 350 return ret; 351 } 352 353 static void ccw_device_oper_notify(struct ccw_device *cdev) 354 { 355 struct subchannel *sch = to_subchannel(cdev->dev.parent); 356 357 if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) { 358 /* Reenable channel measurements, if needed. */ 359 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF); 360 /* Save indication for new paths. */ 361 cdev->private->path_new_mask = sch->vpm; 362 return; 363 } 364 /* Driver doesn't want device back. */ 365 ccw_device_set_notoper(cdev); 366 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND); 367 } 368 369 /* 370 * Finished with online/offline processing. 371 */ 372 static void 373 ccw_device_done(struct ccw_device *cdev, int state) 374 { 375 struct subchannel *sch; 376 377 sch = to_subchannel(cdev->dev.parent); 378 379 ccw_device_set_timeout(cdev, 0); 380 381 if (state != DEV_STATE_ONLINE) 382 cio_disable_subchannel(sch); 383 384 /* Reset device status. */ 385 memset(&cdev->private->irb, 0, sizeof(struct irb)); 386 387 cdev->private->state = state; 388 389 switch (state) { 390 case DEV_STATE_BOXED: 391 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n", 392 cdev->private->dev_id.devno, sch->schid.sch_no); 393 if (cdev->online && 394 ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK) 395 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 396 cdev->private->flags.donotify = 0; 397 break; 398 case DEV_STATE_NOT_OPER: 399 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n", 400 cdev->private->dev_id.devno, sch->schid.sch_no); 401 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 402 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 403 else 404 ccw_device_set_disconnected(cdev); 405 cdev->private->flags.donotify = 0; 406 break; 407 case DEV_STATE_DISCONNECTED: 408 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel " 409 "%04x\n", cdev->private->dev_id.devno, 410 sch->schid.sch_no); 411 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) { 412 cdev->private->state = DEV_STATE_NOT_OPER; 413 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 414 } else 415 ccw_device_set_disconnected(cdev); 416 cdev->private->flags.donotify = 0; 417 break; 418 default: 419 break; 420 } 421 422 if (cdev->private->flags.donotify) { 423 cdev->private->flags.donotify = 0; 424 ccw_device_oper_notify(cdev); 425 } 426 wake_up(&cdev->private->wait_q); 427 } 428 429 /* 430 * Start device recognition. 431 */ 432 void ccw_device_recognition(struct ccw_device *cdev) 433 { 434 struct subchannel *sch = to_subchannel(cdev->dev.parent); 435 436 /* 437 * We used to start here with a sense pgid to find out whether a device 438 * is locked by someone else. Unfortunately, the sense pgid command 439 * code has other meanings on devices predating the path grouping 440 * algorithm, so we start with sense id and box the device after an 441 * timeout (or if sense pgid during path verification detects the device 442 * is locked, as may happen on newer devices). 443 */ 444 cdev->private->flags.recog_done = 0; 445 cdev->private->state = DEV_STATE_SENSE_ID; 446 if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) { 447 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER); 448 return; 449 } 450 ccw_device_sense_id_start(cdev); 451 } 452 453 /* 454 * Handle events for states that use the ccw request infrastructure. 455 */ 456 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e) 457 { 458 switch (e) { 459 case DEV_EVENT_NOTOPER: 460 ccw_request_notoper(cdev); 461 break; 462 case DEV_EVENT_INTERRUPT: 463 ccw_request_handler(cdev); 464 break; 465 case DEV_EVENT_TIMEOUT: 466 ccw_request_timeout(cdev); 467 break; 468 default: 469 break; 470 } 471 } 472 473 static void ccw_device_report_path_events(struct ccw_device *cdev) 474 { 475 struct subchannel *sch = to_subchannel(cdev->dev.parent); 476 int path_event[8]; 477 int chp, mask; 478 479 for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) { 480 path_event[chp] = PE_NONE; 481 if (mask & cdev->private->path_gone_mask & ~(sch->vpm)) 482 path_event[chp] |= PE_PATH_GONE; 483 if (mask & cdev->private->path_new_mask & sch->vpm) 484 path_event[chp] |= PE_PATH_AVAILABLE; 485 if (mask & cdev->private->pgid_reset_mask & sch->vpm) 486 path_event[chp] |= PE_PATHGROUP_ESTABLISHED; 487 } 488 if (cdev->online && cdev->drv->path_event) 489 cdev->drv->path_event(cdev, path_event); 490 } 491 492 static void ccw_device_reset_path_events(struct ccw_device *cdev) 493 { 494 cdev->private->path_gone_mask = 0; 495 cdev->private->path_new_mask = 0; 496 cdev->private->pgid_reset_mask = 0; 497 } 498 499 void 500 ccw_device_verify_done(struct ccw_device *cdev, int err) 501 { 502 struct subchannel *sch; 503 504 sch = to_subchannel(cdev->dev.parent); 505 /* Update schib - pom may have changed. */ 506 if (cio_update_schib(sch)) { 507 err = -ENODEV; 508 goto callback; 509 } 510 /* Update lpm with verified path mask. */ 511 sch->lpm = sch->vpm; 512 /* Repeat path verification? */ 513 if (cdev->private->flags.doverify) { 514 ccw_device_verify_start(cdev); 515 return; 516 } 517 callback: 518 switch (err) { 519 case 0: 520 ccw_device_done(cdev, DEV_STATE_ONLINE); 521 /* Deliver fake irb to device driver, if needed. */ 522 if (cdev->private->flags.fake_irb) { 523 memset(&cdev->private->irb, 0, sizeof(struct irb)); 524 cdev->private->irb.scsw.cmd.cc = 1; 525 cdev->private->irb.scsw.cmd.fctl = SCSW_FCTL_START_FUNC; 526 cdev->private->irb.scsw.cmd.actl = SCSW_ACTL_START_PEND; 527 cdev->private->irb.scsw.cmd.stctl = 528 SCSW_STCTL_STATUS_PEND; 529 cdev->private->flags.fake_irb = 0; 530 if (cdev->handler) 531 cdev->handler(cdev, cdev->private->intparm, 532 &cdev->private->irb); 533 memset(&cdev->private->irb, 0, sizeof(struct irb)); 534 } 535 ccw_device_report_path_events(cdev); 536 break; 537 case -ETIME: 538 case -EUSERS: 539 /* Reset oper notify indication after verify error. */ 540 cdev->private->flags.donotify = 0; 541 ccw_device_done(cdev, DEV_STATE_BOXED); 542 break; 543 case -EACCES: 544 /* Reset oper notify indication after verify error. */ 545 cdev->private->flags.donotify = 0; 546 ccw_device_done(cdev, DEV_STATE_DISCONNECTED); 547 break; 548 default: 549 /* Reset oper notify indication after verify error. */ 550 cdev->private->flags.donotify = 0; 551 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 552 break; 553 } 554 ccw_device_reset_path_events(cdev); 555 } 556 557 /* 558 * Get device online. 559 */ 560 int 561 ccw_device_online(struct ccw_device *cdev) 562 { 563 struct subchannel *sch; 564 int ret; 565 566 if ((cdev->private->state != DEV_STATE_OFFLINE) && 567 (cdev->private->state != DEV_STATE_BOXED)) 568 return -EINVAL; 569 sch = to_subchannel(cdev->dev.parent); 570 ret = cio_enable_subchannel(sch, (u32)(addr_t)sch); 571 if (ret != 0) { 572 /* Couldn't enable the subchannel for i/o. Sick device. */ 573 if (ret == -ENODEV) 574 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 575 return ret; 576 } 577 /* Start initial path verification. */ 578 cdev->private->state = DEV_STATE_VERIFY; 579 ccw_device_verify_start(cdev); 580 return 0; 581 } 582 583 void 584 ccw_device_disband_done(struct ccw_device *cdev, int err) 585 { 586 switch (err) { 587 case 0: 588 ccw_device_done(cdev, DEV_STATE_OFFLINE); 589 break; 590 case -ETIME: 591 ccw_device_done(cdev, DEV_STATE_BOXED); 592 break; 593 default: 594 cdev->private->flags.donotify = 0; 595 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 596 break; 597 } 598 } 599 600 /* 601 * Shutdown device. 602 */ 603 int 604 ccw_device_offline(struct ccw_device *cdev) 605 { 606 struct subchannel *sch; 607 608 /* Allow ccw_device_offline while disconnected. */ 609 if (cdev->private->state == DEV_STATE_DISCONNECTED || 610 cdev->private->state == DEV_STATE_NOT_OPER) { 611 cdev->private->flags.donotify = 0; 612 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 613 return 0; 614 } 615 if (cdev->private->state == DEV_STATE_BOXED) { 616 ccw_device_done(cdev, DEV_STATE_BOXED); 617 return 0; 618 } 619 if (ccw_device_is_orphan(cdev)) { 620 ccw_device_done(cdev, DEV_STATE_OFFLINE); 621 return 0; 622 } 623 sch = to_subchannel(cdev->dev.parent); 624 if (cio_update_schib(sch)) 625 return -ENODEV; 626 if (scsw_actl(&sch->schib.scsw) != 0) 627 return -EBUSY; 628 if (cdev->private->state != DEV_STATE_ONLINE) 629 return -EINVAL; 630 /* Are we doing path grouping? */ 631 if (!cdev->private->flags.pgroup) { 632 /* No, set state offline immediately. */ 633 ccw_device_done(cdev, DEV_STATE_OFFLINE); 634 return 0; 635 } 636 /* Start Set Path Group commands. */ 637 cdev->private->state = DEV_STATE_DISBAND_PGID; 638 ccw_device_disband_start(cdev); 639 return 0; 640 } 641 642 /* 643 * Handle not operational event in non-special state. 644 */ 645 static void ccw_device_generic_notoper(struct ccw_device *cdev, 646 enum dev_event dev_event) 647 { 648 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 649 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 650 else 651 ccw_device_set_disconnected(cdev); 652 } 653 654 /* 655 * Handle path verification event in offline state. 656 */ 657 static void ccw_device_offline_verify(struct ccw_device *cdev, 658 enum dev_event dev_event) 659 { 660 struct subchannel *sch = to_subchannel(cdev->dev.parent); 661 662 css_schedule_eval(sch->schid); 663 } 664 665 /* 666 * Handle path verification event. 667 */ 668 static void 669 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event) 670 { 671 struct subchannel *sch; 672 673 if (cdev->private->state == DEV_STATE_W4SENSE) { 674 cdev->private->flags.doverify = 1; 675 return; 676 } 677 sch = to_subchannel(cdev->dev.parent); 678 /* 679 * Since we might not just be coming from an interrupt from the 680 * subchannel we have to update the schib. 681 */ 682 if (cio_update_schib(sch)) { 683 ccw_device_verify_done(cdev, -ENODEV); 684 return; 685 } 686 687 if (scsw_actl(&sch->schib.scsw) != 0 || 688 (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) || 689 (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) { 690 /* 691 * No final status yet or final status not yet delivered 692 * to the device driver. Can't do path verification now, 693 * delay until final status was delivered. 694 */ 695 cdev->private->flags.doverify = 1; 696 return; 697 } 698 /* Device is idle, we can do the path verification. */ 699 cdev->private->state = DEV_STATE_VERIFY; 700 ccw_device_verify_start(cdev); 701 } 702 703 /* 704 * Handle path verification event in boxed state. 705 */ 706 static void ccw_device_boxed_verify(struct ccw_device *cdev, 707 enum dev_event dev_event) 708 { 709 struct subchannel *sch = to_subchannel(cdev->dev.parent); 710 711 if (cdev->online) { 712 if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) 713 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 714 else 715 ccw_device_online_verify(cdev, dev_event); 716 } else 717 css_schedule_eval(sch->schid); 718 } 719 720 /* 721 * Got an interrupt for a normal io (state online). 722 */ 723 static void 724 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event) 725 { 726 struct irb *irb; 727 int is_cmd; 728 729 irb = (struct irb *)&S390_lowcore.irb; 730 is_cmd = !scsw_is_tm(&irb->scsw); 731 /* Check for unsolicited interrupt. */ 732 if (!scsw_is_solicited(&irb->scsw)) { 733 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) && 734 !irb->esw.esw0.erw.cons) { 735 /* Unit check but no sense data. Need basic sense. */ 736 if (ccw_device_do_sense(cdev, irb) != 0) 737 goto call_handler_unsol; 738 memcpy(&cdev->private->irb, irb, sizeof(struct irb)); 739 cdev->private->state = DEV_STATE_W4SENSE; 740 cdev->private->intparm = 0; 741 return; 742 } 743 call_handler_unsol: 744 if (cdev->handler) 745 cdev->handler (cdev, 0, irb); 746 if (cdev->private->flags.doverify) 747 ccw_device_online_verify(cdev, 0); 748 return; 749 } 750 /* Accumulate status and find out if a basic sense is needed. */ 751 ccw_device_accumulate_irb(cdev, irb); 752 if (is_cmd && cdev->private->flags.dosense) { 753 if (ccw_device_do_sense(cdev, irb) == 0) { 754 cdev->private->state = DEV_STATE_W4SENSE; 755 } 756 return; 757 } 758 /* Call the handler. */ 759 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) 760 /* Start delayed path verification. */ 761 ccw_device_online_verify(cdev, 0); 762 } 763 764 /* 765 * Got an timeout in online state. 766 */ 767 static void 768 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event) 769 { 770 int ret; 771 772 ccw_device_set_timeout(cdev, 0); 773 cdev->private->iretry = 255; 774 ret = ccw_device_cancel_halt_clear(cdev); 775 if (ret == -EBUSY) { 776 ccw_device_set_timeout(cdev, 3*HZ); 777 cdev->private->state = DEV_STATE_TIMEOUT_KILL; 778 return; 779 } 780 if (ret) 781 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 782 else if (cdev->handler) 783 cdev->handler(cdev, cdev->private->intparm, 784 ERR_PTR(-ETIMEDOUT)); 785 } 786 787 /* 788 * Got an interrupt for a basic sense. 789 */ 790 static void 791 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event) 792 { 793 struct irb *irb; 794 795 irb = (struct irb *)&S390_lowcore.irb; 796 /* Check for unsolicited interrupt. */ 797 if (scsw_stctl(&irb->scsw) == 798 (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { 799 if (scsw_cc(&irb->scsw) == 1) 800 /* Basic sense hasn't started. Try again. */ 801 ccw_device_do_sense(cdev, irb); 802 else { 803 CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited " 804 "interrupt during w4sense...\n", 805 cdev->private->dev_id.ssid, 806 cdev->private->dev_id.devno); 807 if (cdev->handler) 808 cdev->handler (cdev, 0, irb); 809 } 810 return; 811 } 812 /* 813 * Check if a halt or clear has been issued in the meanwhile. If yes, 814 * only deliver the halt/clear interrupt to the device driver as if it 815 * had killed the original request. 816 */ 817 if (scsw_fctl(&irb->scsw) & 818 (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) { 819 cdev->private->flags.dosense = 0; 820 memset(&cdev->private->irb, 0, sizeof(struct irb)); 821 ccw_device_accumulate_irb(cdev, irb); 822 goto call_handler; 823 } 824 /* Add basic sense info to irb. */ 825 ccw_device_accumulate_basic_sense(cdev, irb); 826 if (cdev->private->flags.dosense) { 827 /* Another basic sense is needed. */ 828 ccw_device_do_sense(cdev, irb); 829 return; 830 } 831 call_handler: 832 cdev->private->state = DEV_STATE_ONLINE; 833 /* In case sensing interfered with setting the device online */ 834 wake_up(&cdev->private->wait_q); 835 /* Call the handler. */ 836 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) 837 /* Start delayed path verification. */ 838 ccw_device_online_verify(cdev, 0); 839 } 840 841 static void 842 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event) 843 { 844 ccw_device_set_timeout(cdev, 0); 845 /* Start delayed path verification. */ 846 ccw_device_online_verify(cdev, 0); 847 /* OK, i/o is dead now. Call interrupt handler. */ 848 if (cdev->handler) 849 cdev->handler(cdev, cdev->private->intparm, 850 ERR_PTR(-EIO)); 851 } 852 853 static void 854 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event) 855 { 856 int ret; 857 858 ret = ccw_device_cancel_halt_clear(cdev); 859 if (ret == -EBUSY) { 860 ccw_device_set_timeout(cdev, 3*HZ); 861 return; 862 } 863 /* Start delayed path verification. */ 864 ccw_device_online_verify(cdev, 0); 865 if (cdev->handler) 866 cdev->handler(cdev, cdev->private->intparm, 867 ERR_PTR(-EIO)); 868 } 869 870 void ccw_device_kill_io(struct ccw_device *cdev) 871 { 872 int ret; 873 874 cdev->private->iretry = 255; 875 ret = ccw_device_cancel_halt_clear(cdev); 876 if (ret == -EBUSY) { 877 ccw_device_set_timeout(cdev, 3*HZ); 878 cdev->private->state = DEV_STATE_TIMEOUT_KILL; 879 return; 880 } 881 /* Start delayed path verification. */ 882 ccw_device_online_verify(cdev, 0); 883 if (cdev->handler) 884 cdev->handler(cdev, cdev->private->intparm, 885 ERR_PTR(-EIO)); 886 } 887 888 static void 889 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event) 890 { 891 /* Start verification after current task finished. */ 892 cdev->private->flags.doverify = 1; 893 } 894 895 static void 896 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event) 897 { 898 struct subchannel *sch; 899 900 sch = to_subchannel(cdev->dev.parent); 901 if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0) 902 /* Couldn't enable the subchannel for i/o. Sick device. */ 903 return; 904 cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID; 905 ccw_device_sense_id_start(cdev); 906 } 907 908 void ccw_device_trigger_reprobe(struct ccw_device *cdev) 909 { 910 struct subchannel *sch; 911 912 if (cdev->private->state != DEV_STATE_DISCONNECTED) 913 return; 914 915 sch = to_subchannel(cdev->dev.parent); 916 /* Update some values. */ 917 if (cio_update_schib(sch)) 918 return; 919 /* 920 * The pim, pam, pom values may not be accurate, but they are the best 921 * we have before performing device selection :/ 922 */ 923 sch->lpm = sch->schib.pmcw.pam & sch->opm; 924 /* 925 * Use the initial configuration since we can't be shure that the old 926 * paths are valid. 927 */ 928 io_subchannel_init_config(sch); 929 if (cio_commit_config(sch)) 930 return; 931 932 /* We should also udate ssd info, but this has to wait. */ 933 /* Check if this is another device which appeared on the same sch. */ 934 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) 935 css_schedule_eval(sch->schid); 936 else 937 ccw_device_start_id(cdev, 0); 938 } 939 940 static void ccw_device_disabled_irq(struct ccw_device *cdev, 941 enum dev_event dev_event) 942 { 943 struct subchannel *sch; 944 945 sch = to_subchannel(cdev->dev.parent); 946 /* 947 * An interrupt in a disabled state means a previous disable was not 948 * successful - should not happen, but we try to disable again. 949 */ 950 cio_disable_subchannel(sch); 951 } 952 953 static void 954 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event) 955 { 956 retry_set_schib(cdev); 957 cdev->private->state = DEV_STATE_ONLINE; 958 dev_fsm_event(cdev, dev_event); 959 } 960 961 static void ccw_device_update_cmfblock(struct ccw_device *cdev, 962 enum dev_event dev_event) 963 { 964 cmf_retry_copy_block(cdev); 965 cdev->private->state = DEV_STATE_ONLINE; 966 dev_fsm_event(cdev, dev_event); 967 } 968 969 static void 970 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event) 971 { 972 ccw_device_set_timeout(cdev, 0); 973 cdev->private->state = DEV_STATE_NOT_OPER; 974 wake_up(&cdev->private->wait_q); 975 } 976 977 static void 978 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event) 979 { 980 int ret; 981 982 ret = ccw_device_cancel_halt_clear(cdev); 983 if (ret == -EBUSY) { 984 ccw_device_set_timeout(cdev, HZ/10); 985 } else { 986 cdev->private->state = DEV_STATE_NOT_OPER; 987 wake_up(&cdev->private->wait_q); 988 } 989 } 990 991 /* 992 * No operation action. This is used e.g. to ignore a timeout event in 993 * state offline. 994 */ 995 static void 996 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event) 997 { 998 } 999 1000 /* 1001 * device statemachine 1002 */ 1003 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = { 1004 [DEV_STATE_NOT_OPER] = { 1005 [DEV_EVENT_NOTOPER] = ccw_device_nop, 1006 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq, 1007 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1008 [DEV_EVENT_VERIFY] = ccw_device_nop, 1009 }, 1010 [DEV_STATE_SENSE_PGID] = { 1011 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1012 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1013 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1014 [DEV_EVENT_VERIFY] = ccw_device_nop, 1015 }, 1016 [DEV_STATE_SENSE_ID] = { 1017 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1018 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1019 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1020 [DEV_EVENT_VERIFY] = ccw_device_nop, 1021 }, 1022 [DEV_STATE_OFFLINE] = { 1023 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1024 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq, 1025 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1026 [DEV_EVENT_VERIFY] = ccw_device_offline_verify, 1027 }, 1028 [DEV_STATE_VERIFY] = { 1029 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1030 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1031 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1032 [DEV_EVENT_VERIFY] = ccw_device_delay_verify, 1033 }, 1034 [DEV_STATE_ONLINE] = { 1035 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1036 [DEV_EVENT_INTERRUPT] = ccw_device_irq, 1037 [DEV_EVENT_TIMEOUT] = ccw_device_online_timeout, 1038 [DEV_EVENT_VERIFY] = ccw_device_online_verify, 1039 }, 1040 [DEV_STATE_W4SENSE] = { 1041 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1042 [DEV_EVENT_INTERRUPT] = ccw_device_w4sense, 1043 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1044 [DEV_EVENT_VERIFY] = ccw_device_online_verify, 1045 }, 1046 [DEV_STATE_DISBAND_PGID] = { 1047 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1048 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1049 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1050 [DEV_EVENT_VERIFY] = ccw_device_nop, 1051 }, 1052 [DEV_STATE_BOXED] = { 1053 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1054 [DEV_EVENT_INTERRUPT] = ccw_device_nop, 1055 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1056 [DEV_EVENT_VERIFY] = ccw_device_boxed_verify, 1057 }, 1058 /* states to wait for i/o completion before doing something */ 1059 [DEV_STATE_TIMEOUT_KILL] = { 1060 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1061 [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq, 1062 [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout, 1063 [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME 1064 }, 1065 [DEV_STATE_QUIESCE] = { 1066 [DEV_EVENT_NOTOPER] = ccw_device_quiesce_done, 1067 [DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done, 1068 [DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout, 1069 [DEV_EVENT_VERIFY] = ccw_device_nop, 1070 }, 1071 /* special states for devices gone not operational */ 1072 [DEV_STATE_DISCONNECTED] = { 1073 [DEV_EVENT_NOTOPER] = ccw_device_nop, 1074 [DEV_EVENT_INTERRUPT] = ccw_device_start_id, 1075 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1076 [DEV_EVENT_VERIFY] = ccw_device_start_id, 1077 }, 1078 [DEV_STATE_DISCONNECTED_SENSE_ID] = { 1079 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1080 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1081 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1082 [DEV_EVENT_VERIFY] = ccw_device_nop, 1083 }, 1084 [DEV_STATE_CMFCHANGE] = { 1085 [DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate, 1086 [DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate, 1087 [DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate, 1088 [DEV_EVENT_VERIFY] = ccw_device_change_cmfstate, 1089 }, 1090 [DEV_STATE_CMFUPDATE] = { 1091 [DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock, 1092 [DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock, 1093 [DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock, 1094 [DEV_EVENT_VERIFY] = ccw_device_update_cmfblock, 1095 }, 1096 [DEV_STATE_STEAL_LOCK] = { 1097 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1098 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1099 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1100 [DEV_EVENT_VERIFY] = ccw_device_nop, 1101 }, 1102 }; 1103 1104 EXPORT_SYMBOL_GPL(ccw_device_set_timeout); 1105