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 (cornelia.huck@de.ibm.com) 7 * Martin Schwidefsky (schwidefsky@de.ibm.com) 8 */ 9 10 #include <linux/module.h> 11 #include <linux/init.h> 12 #include <linux/jiffies.h> 13 #include <linux/string.h> 14 15 #include <asm/ccwdev.h> 16 #include <asm/cio.h> 17 #include <asm/chpid.h> 18 19 #include "cio.h" 20 #include "cio_debug.h" 21 #include "css.h" 22 #include "device.h" 23 #include "chsc.h" 24 #include "ioasm.h" 25 #include "chp.h" 26 27 static int timeout_log_enabled; 28 29 static int __init ccw_timeout_log_setup(char *unused) 30 { 31 timeout_log_enabled = 1; 32 return 1; 33 } 34 35 __setup("ccw_timeout_log", ccw_timeout_log_setup); 36 37 static void ccw_timeout_log(struct ccw_device *cdev) 38 { 39 struct schib schib; 40 struct subchannel *sch; 41 struct io_subchannel_private *private; 42 union orb *orb; 43 int cc; 44 45 sch = to_subchannel(cdev->dev.parent); 46 private = to_io_private(sch); 47 orb = &private->orb; 48 cc = stsch(sch->schid, &schib); 49 50 printk(KERN_WARNING "cio: ccw device timeout occurred at %llx, " 51 "device information:\n", get_tod_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 == 71 &private->dma_area->sense_ccw || 72 (void *)(addr_t)orb->cmd.cpa == 73 cdev->private->dma_area->iccws) 74 printk(KERN_WARNING "cio: last channel program " 75 "(intern):\n"); 76 else 77 printk(KERN_WARNING "cio: last channel program:\n"); 78 79 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1, 80 (void *)(addr_t)orb->cmd.cpa, 81 sizeof(struct ccw1), 0); 82 } 83 printk(KERN_WARNING "cio: ccw device state: %d\n", 84 cdev->private->state); 85 printk(KERN_WARNING "cio: store subchannel returned: cc=%d\n", cc); 86 printk(KERN_WARNING "cio: schib:\n"); 87 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1, 88 &schib, sizeof(schib), 0); 89 printk(KERN_WARNING "cio: ccw device flags:\n"); 90 print_hex_dump(KERN_WARNING, "cio: ", DUMP_PREFIX_NONE, 16, 1, 91 &cdev->private->flags, sizeof(cdev->private->flags), 0); 92 } 93 94 /* 95 * Timeout function. It just triggers a DEV_EVENT_TIMEOUT. 96 */ 97 void 98 ccw_device_timeout(struct timer_list *t) 99 { 100 struct ccw_device_private *priv = from_timer(priv, t, timer); 101 struct ccw_device *cdev = priv->cdev; 102 103 spin_lock_irq(cdev->ccwlock); 104 if (timeout_log_enabled) 105 ccw_timeout_log(cdev); 106 dev_fsm_event(cdev, DEV_EVENT_TIMEOUT); 107 spin_unlock_irq(cdev->ccwlock); 108 } 109 110 /* 111 * Set timeout 112 */ 113 void 114 ccw_device_set_timeout(struct ccw_device *cdev, int expires) 115 { 116 if (expires == 0) { 117 del_timer(&cdev->private->timer); 118 return; 119 } 120 if (timer_pending(&cdev->private->timer)) { 121 if (mod_timer(&cdev->private->timer, jiffies + expires)) 122 return; 123 } 124 cdev->private->timer.expires = jiffies + expires; 125 add_timer(&cdev->private->timer); 126 } 127 128 int 129 ccw_device_cancel_halt_clear(struct ccw_device *cdev) 130 { 131 struct subchannel *sch; 132 int ret; 133 134 sch = to_subchannel(cdev->dev.parent); 135 ret = cio_cancel_halt_clear(sch, &cdev->private->iretry); 136 137 if (ret == -EIO) 138 CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n", 139 cdev->private->dev_id.ssid, 140 cdev->private->dev_id.devno); 141 142 return ret; 143 } 144 145 void ccw_device_update_sense_data(struct ccw_device *cdev) 146 { 147 memset(&cdev->id, 0, sizeof(cdev->id)); 148 cdev->id.cu_type = cdev->private->dma_area->senseid.cu_type; 149 cdev->id.cu_model = cdev->private->dma_area->senseid.cu_model; 150 cdev->id.dev_type = cdev->private->dma_area->senseid.dev_type; 151 cdev->id.dev_model = cdev->private->dma_area->senseid.dev_model; 152 } 153 154 int ccw_device_test_sense_data(struct ccw_device *cdev) 155 { 156 return cdev->id.cu_type == 157 cdev->private->dma_area->senseid.cu_type && 158 cdev->id.cu_model == 159 cdev->private->dma_area->senseid.cu_model && 160 cdev->id.dev_type == 161 cdev->private->dma_area->senseid.dev_type && 162 cdev->id.dev_model == 163 cdev->private->dma_area->senseid.dev_model; 164 } 165 166 /* 167 * The machine won't give us any notification by machine check if a chpid has 168 * been varied online on the SE so we have to find out by magic (i. e. driving 169 * the channel subsystem to device selection and updating our path masks). 170 */ 171 static void 172 __recover_lost_chpids(struct subchannel *sch, int old_lpm) 173 { 174 int mask, i; 175 struct chp_id chpid; 176 177 chp_id_init(&chpid); 178 for (i = 0; i<8; i++) { 179 mask = 0x80 >> i; 180 if (!(sch->lpm & mask)) 181 continue; 182 if (old_lpm & mask) 183 continue; 184 chpid.id = sch->schib.pmcw.chpid[i]; 185 if (!chp_is_registered(chpid)) 186 css_schedule_eval_all(); 187 } 188 } 189 190 /* 191 * Stop device recognition. 192 */ 193 static void 194 ccw_device_recog_done(struct ccw_device *cdev, int state) 195 { 196 struct subchannel *sch; 197 int old_lpm; 198 199 sch = to_subchannel(cdev->dev.parent); 200 201 if (cio_disable_subchannel(sch)) 202 state = DEV_STATE_NOT_OPER; 203 /* 204 * Now that we tried recognition, we have performed device selection 205 * through ssch() and the path information is up to date. 206 */ 207 old_lpm = sch->lpm; 208 209 /* Check since device may again have become not operational. */ 210 if (cio_update_schib(sch)) 211 state = DEV_STATE_NOT_OPER; 212 else 213 sch->lpm = sch->schib.pmcw.pam & sch->opm; 214 215 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) 216 /* Force reprobe on all chpids. */ 217 old_lpm = 0; 218 if (sch->lpm != old_lpm) 219 __recover_lost_chpids(sch, old_lpm); 220 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID && 221 (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) { 222 cdev->private->flags.recog_done = 1; 223 cdev->private->state = DEV_STATE_DISCONNECTED; 224 wake_up(&cdev->private->wait_q); 225 return; 226 } 227 if (cdev->private->flags.resuming) { 228 cdev->private->state = state; 229 cdev->private->flags.recog_done = 1; 230 wake_up(&cdev->private->wait_q); 231 return; 232 } 233 switch (state) { 234 case DEV_STATE_NOT_OPER: 235 break; 236 case DEV_STATE_OFFLINE: 237 if (!cdev->online) { 238 ccw_device_update_sense_data(cdev); 239 break; 240 } 241 cdev->private->state = DEV_STATE_OFFLINE; 242 cdev->private->flags.recog_done = 1; 243 if (ccw_device_test_sense_data(cdev)) { 244 cdev->private->flags.donotify = 1; 245 ccw_device_online(cdev); 246 wake_up(&cdev->private->wait_q); 247 } else { 248 ccw_device_update_sense_data(cdev); 249 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND); 250 } 251 return; 252 case DEV_STATE_BOXED: 253 if (cdev->id.cu_type != 0) { /* device was recognized before */ 254 cdev->private->flags.recog_done = 1; 255 cdev->private->state = DEV_STATE_BOXED; 256 wake_up(&cdev->private->wait_q); 257 return; 258 } 259 break; 260 } 261 cdev->private->state = state; 262 io_subchannel_recog_done(cdev); 263 wake_up(&cdev->private->wait_q); 264 } 265 266 /* 267 * Function called from device_id.c after sense id has completed. 268 */ 269 void 270 ccw_device_sense_id_done(struct ccw_device *cdev, int err) 271 { 272 switch (err) { 273 case 0: 274 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE); 275 break; 276 case -ETIME: /* Sense id stopped by timeout. */ 277 ccw_device_recog_done(cdev, DEV_STATE_BOXED); 278 break; 279 default: 280 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER); 281 break; 282 } 283 } 284 285 /** 286 * ccw_device_notify() - inform the device's driver about an event 287 * @cdev: device for which an event occurred 288 * @event: event that occurred 289 * 290 * Returns: 291 * -%EINVAL if the device is offline or has no driver. 292 * -%EOPNOTSUPP if the device's driver has no notifier registered. 293 * %NOTIFY_OK if the driver wants to keep the device. 294 * %NOTIFY_BAD if the driver doesn't want to keep the device. 295 */ 296 int ccw_device_notify(struct ccw_device *cdev, int event) 297 { 298 int ret = -EINVAL; 299 300 if (!cdev->drv) 301 goto out; 302 if (!cdev->online) 303 goto out; 304 CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n", 305 cdev->private->dev_id.ssid, cdev->private->dev_id.devno, 306 event); 307 if (!cdev->drv->notify) { 308 ret = -EOPNOTSUPP; 309 goto out; 310 } 311 if (cdev->drv->notify(cdev, event)) 312 ret = NOTIFY_OK; 313 else 314 ret = NOTIFY_BAD; 315 out: 316 return ret; 317 } 318 319 static void ccw_device_oper_notify(struct ccw_device *cdev) 320 { 321 struct subchannel *sch = to_subchannel(cdev->dev.parent); 322 323 if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) { 324 /* Reenable channel measurements, if needed. */ 325 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF); 326 /* Save indication for new paths. */ 327 cdev->private->path_new_mask = sch->vpm; 328 return; 329 } 330 /* Driver doesn't want device back. */ 331 ccw_device_set_notoper(cdev); 332 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND); 333 } 334 335 /* 336 * Finished with online/offline processing. 337 */ 338 static void 339 ccw_device_done(struct ccw_device *cdev, int state) 340 { 341 struct subchannel *sch; 342 343 sch = to_subchannel(cdev->dev.parent); 344 345 ccw_device_set_timeout(cdev, 0); 346 347 if (state != DEV_STATE_ONLINE) 348 cio_disable_subchannel(sch); 349 350 /* Reset device status. */ 351 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb)); 352 353 cdev->private->state = state; 354 355 switch (state) { 356 case DEV_STATE_BOXED: 357 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n", 358 cdev->private->dev_id.devno, sch->schid.sch_no); 359 if (cdev->online && 360 ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK) 361 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 362 cdev->private->flags.donotify = 0; 363 break; 364 case DEV_STATE_NOT_OPER: 365 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n", 366 cdev->private->dev_id.devno, sch->schid.sch_no); 367 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 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 case DEV_STATE_DISCONNECTED: 374 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel " 375 "%04x\n", cdev->private->dev_id.devno, 376 sch->schid.sch_no); 377 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) { 378 cdev->private->state = DEV_STATE_NOT_OPER; 379 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 380 } else 381 ccw_device_set_disconnected(cdev); 382 cdev->private->flags.donotify = 0; 383 break; 384 default: 385 break; 386 } 387 388 if (cdev->private->flags.donotify) { 389 cdev->private->flags.donotify = 0; 390 ccw_device_oper_notify(cdev); 391 } 392 wake_up(&cdev->private->wait_q); 393 } 394 395 /* 396 * Start device recognition. 397 */ 398 void ccw_device_recognition(struct ccw_device *cdev) 399 { 400 struct subchannel *sch = to_subchannel(cdev->dev.parent); 401 402 /* 403 * We used to start here with a sense pgid to find out whether a device 404 * is locked by someone else. Unfortunately, the sense pgid command 405 * code has other meanings on devices predating the path grouping 406 * algorithm, so we start with sense id and box the device after an 407 * timeout (or if sense pgid during path verification detects the device 408 * is locked, as may happen on newer devices). 409 */ 410 cdev->private->flags.recog_done = 0; 411 cdev->private->state = DEV_STATE_SENSE_ID; 412 if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) { 413 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER); 414 return; 415 } 416 ccw_device_sense_id_start(cdev); 417 } 418 419 /* 420 * Handle events for states that use the ccw request infrastructure. 421 */ 422 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e) 423 { 424 switch (e) { 425 case DEV_EVENT_NOTOPER: 426 ccw_request_notoper(cdev); 427 break; 428 case DEV_EVENT_INTERRUPT: 429 ccw_request_handler(cdev); 430 break; 431 case DEV_EVENT_TIMEOUT: 432 ccw_request_timeout(cdev); 433 break; 434 default: 435 break; 436 } 437 } 438 439 static void ccw_device_report_path_events(struct ccw_device *cdev) 440 { 441 struct subchannel *sch = to_subchannel(cdev->dev.parent); 442 int path_event[8]; 443 int chp, mask; 444 445 for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) { 446 path_event[chp] = PE_NONE; 447 if (mask & cdev->private->path_gone_mask & ~(sch->vpm)) 448 path_event[chp] |= PE_PATH_GONE; 449 if (mask & cdev->private->path_new_mask & sch->vpm) 450 path_event[chp] |= PE_PATH_AVAILABLE; 451 if (mask & cdev->private->pgid_reset_mask & sch->vpm) 452 path_event[chp] |= PE_PATHGROUP_ESTABLISHED; 453 } 454 if (cdev->online && cdev->drv->path_event) 455 cdev->drv->path_event(cdev, path_event); 456 } 457 458 static void ccw_device_reset_path_events(struct ccw_device *cdev) 459 { 460 cdev->private->path_gone_mask = 0; 461 cdev->private->path_new_mask = 0; 462 cdev->private->pgid_reset_mask = 0; 463 } 464 465 static void create_fake_irb(struct irb *irb, int type) 466 { 467 memset(irb, 0, sizeof(*irb)); 468 if (type == FAKE_CMD_IRB) { 469 struct cmd_scsw *scsw = &irb->scsw.cmd; 470 scsw->cc = 1; 471 scsw->fctl = SCSW_FCTL_START_FUNC; 472 scsw->actl = SCSW_ACTL_START_PEND; 473 scsw->stctl = SCSW_STCTL_STATUS_PEND; 474 } else if (type == FAKE_TM_IRB) { 475 struct tm_scsw *scsw = &irb->scsw.tm; 476 scsw->x = 1; 477 scsw->cc = 1; 478 scsw->fctl = SCSW_FCTL_START_FUNC; 479 scsw->actl = SCSW_ACTL_START_PEND; 480 scsw->stctl = SCSW_STCTL_STATUS_PEND; 481 } 482 } 483 484 static void ccw_device_handle_broken_paths(struct ccw_device *cdev) 485 { 486 struct subchannel *sch = to_subchannel(cdev->dev.parent); 487 u8 broken_paths = (sch->schib.pmcw.pam & sch->opm) ^ sch->vpm; 488 489 if (broken_paths && (cdev->private->path_broken_mask != broken_paths)) 490 ccw_device_schedule_recovery(); 491 492 cdev->private->path_broken_mask = broken_paths; 493 } 494 495 void ccw_device_verify_done(struct ccw_device *cdev, int err) 496 { 497 struct subchannel *sch; 498 499 sch = to_subchannel(cdev->dev.parent); 500 /* Update schib - pom may have changed. */ 501 if (cio_update_schib(sch)) { 502 err = -ENODEV; 503 goto callback; 504 } 505 /* Update lpm with verified path mask. */ 506 sch->lpm = sch->vpm; 507 /* Repeat path verification? */ 508 if (cdev->private->flags.doverify) { 509 ccw_device_verify_start(cdev); 510 return; 511 } 512 callback: 513 switch (err) { 514 case 0: 515 ccw_device_done(cdev, DEV_STATE_ONLINE); 516 /* Deliver fake irb to device driver, if needed. */ 517 if (cdev->private->flags.fake_irb) { 518 create_fake_irb(&cdev->private->dma_area->irb, 519 cdev->private->flags.fake_irb); 520 cdev->private->flags.fake_irb = 0; 521 if (cdev->handler) 522 cdev->handler(cdev, cdev->private->intparm, 523 &cdev->private->dma_area->irb); 524 memset(&cdev->private->dma_area->irb, 0, 525 sizeof(struct irb)); 526 } 527 ccw_device_report_path_events(cdev); 528 ccw_device_handle_broken_paths(cdev); 529 break; 530 case -ETIME: 531 case -EUSERS: 532 /* Reset oper notify indication after verify error. */ 533 cdev->private->flags.donotify = 0; 534 ccw_device_done(cdev, DEV_STATE_BOXED); 535 break; 536 case -EACCES: 537 /* Reset oper notify indication after verify error. */ 538 cdev->private->flags.donotify = 0; 539 ccw_device_done(cdev, DEV_STATE_DISCONNECTED); 540 break; 541 default: 542 /* Reset oper notify indication after verify error. */ 543 cdev->private->flags.donotify = 0; 544 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 545 break; 546 } 547 ccw_device_reset_path_events(cdev); 548 } 549 550 /* 551 * Get device online. 552 */ 553 int 554 ccw_device_online(struct ccw_device *cdev) 555 { 556 struct subchannel *sch; 557 int ret; 558 559 if ((cdev->private->state != DEV_STATE_OFFLINE) && 560 (cdev->private->state != DEV_STATE_BOXED)) 561 return -EINVAL; 562 sch = to_subchannel(cdev->dev.parent); 563 ret = cio_enable_subchannel(sch, (u32)(addr_t)sch); 564 if (ret != 0) { 565 /* Couldn't enable the subchannel for i/o. Sick device. */ 566 if (ret == -ENODEV) 567 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 568 return ret; 569 } 570 /* Start initial path verification. */ 571 cdev->private->state = DEV_STATE_VERIFY; 572 ccw_device_verify_start(cdev); 573 return 0; 574 } 575 576 void 577 ccw_device_disband_done(struct ccw_device *cdev, int err) 578 { 579 switch (err) { 580 case 0: 581 ccw_device_done(cdev, DEV_STATE_OFFLINE); 582 break; 583 case -ETIME: 584 ccw_device_done(cdev, DEV_STATE_BOXED); 585 break; 586 default: 587 cdev->private->flags.donotify = 0; 588 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 589 break; 590 } 591 } 592 593 /* 594 * Shutdown device. 595 */ 596 int 597 ccw_device_offline(struct ccw_device *cdev) 598 { 599 struct subchannel *sch; 600 601 /* Allow ccw_device_offline while disconnected. */ 602 if (cdev->private->state == DEV_STATE_DISCONNECTED || 603 cdev->private->state == DEV_STATE_NOT_OPER) { 604 cdev->private->flags.donotify = 0; 605 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 606 return 0; 607 } 608 if (cdev->private->state == DEV_STATE_BOXED) { 609 ccw_device_done(cdev, DEV_STATE_BOXED); 610 return 0; 611 } 612 if (ccw_device_is_orphan(cdev)) { 613 ccw_device_done(cdev, DEV_STATE_OFFLINE); 614 return 0; 615 } 616 sch = to_subchannel(cdev->dev.parent); 617 if (cio_update_schib(sch)) 618 return -ENODEV; 619 if (scsw_actl(&sch->schib.scsw) != 0) 620 return -EBUSY; 621 if (cdev->private->state != DEV_STATE_ONLINE) 622 return -EINVAL; 623 /* Are we doing path grouping? */ 624 if (!cdev->private->flags.pgroup) { 625 /* No, set state offline immediately. */ 626 ccw_device_done(cdev, DEV_STATE_OFFLINE); 627 return 0; 628 } 629 /* Start Set Path Group commands. */ 630 cdev->private->state = DEV_STATE_DISBAND_PGID; 631 ccw_device_disband_start(cdev); 632 return 0; 633 } 634 635 /* 636 * Handle not operational event in non-special state. 637 */ 638 static void ccw_device_generic_notoper(struct ccw_device *cdev, 639 enum dev_event dev_event) 640 { 641 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 642 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 643 else 644 ccw_device_set_disconnected(cdev); 645 } 646 647 /* 648 * Handle path verification event in offline state. 649 */ 650 static void ccw_device_offline_verify(struct ccw_device *cdev, 651 enum dev_event dev_event) 652 { 653 struct subchannel *sch = to_subchannel(cdev->dev.parent); 654 655 css_schedule_eval(sch->schid); 656 } 657 658 /* 659 * Handle path verification event. 660 */ 661 static void 662 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event) 663 { 664 struct subchannel *sch; 665 666 if (cdev->private->state == DEV_STATE_W4SENSE) { 667 cdev->private->flags.doverify = 1; 668 return; 669 } 670 sch = to_subchannel(cdev->dev.parent); 671 /* 672 * Since we might not just be coming from an interrupt from the 673 * subchannel we have to update the schib. 674 */ 675 if (cio_update_schib(sch)) { 676 ccw_device_verify_done(cdev, -ENODEV); 677 return; 678 } 679 680 if (scsw_actl(&sch->schib.scsw) != 0 || 681 (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) || 682 (scsw_stctl(&cdev->private->dma_area->irb.scsw) & 683 SCSW_STCTL_STATUS_PEND)) { 684 /* 685 * No final status yet or final status not yet delivered 686 * to the device driver. Can't do path verification now, 687 * delay until final status was delivered. 688 */ 689 cdev->private->flags.doverify = 1; 690 return; 691 } 692 /* Device is idle, we can do the path verification. */ 693 cdev->private->state = DEV_STATE_VERIFY; 694 ccw_device_verify_start(cdev); 695 } 696 697 /* 698 * Handle path verification event in boxed state. 699 */ 700 static void ccw_device_boxed_verify(struct ccw_device *cdev, 701 enum dev_event dev_event) 702 { 703 struct subchannel *sch = to_subchannel(cdev->dev.parent); 704 705 if (cdev->online) { 706 if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) 707 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 708 else 709 ccw_device_online_verify(cdev, dev_event); 710 } else 711 css_schedule_eval(sch->schid); 712 } 713 714 /* 715 * Pass interrupt to device driver. 716 */ 717 static int ccw_device_call_handler(struct ccw_device *cdev) 718 { 719 unsigned int stctl; 720 int ending_status; 721 722 /* 723 * we allow for the device action handler if . 724 * - we received ending status 725 * - the action handler requested to see all interrupts 726 * - we received an intermediate status 727 * - fast notification was requested (primary status) 728 * - unsolicited interrupts 729 */ 730 stctl = scsw_stctl(&cdev->private->dma_area->irb.scsw); 731 ending_status = (stctl & SCSW_STCTL_SEC_STATUS) || 732 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) || 733 (stctl == SCSW_STCTL_STATUS_PEND); 734 if (!ending_status && 735 !cdev->private->options.repall && 736 !(stctl & SCSW_STCTL_INTER_STATUS) && 737 !(cdev->private->options.fast && 738 (stctl & SCSW_STCTL_PRIM_STATUS))) 739 return 0; 740 741 if (ending_status) 742 ccw_device_set_timeout(cdev, 0); 743 744 if (cdev->handler) 745 cdev->handler(cdev, cdev->private->intparm, 746 &cdev->private->dma_area->irb); 747 748 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb)); 749 return 1; 750 } 751 752 /* 753 * Got an interrupt for a normal io (state online). 754 */ 755 static void 756 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event) 757 { 758 struct irb *irb; 759 int is_cmd; 760 761 irb = this_cpu_ptr(&cio_irb); 762 is_cmd = !scsw_is_tm(&irb->scsw); 763 /* Check for unsolicited interrupt. */ 764 if (!scsw_is_solicited(&irb->scsw)) { 765 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) && 766 !irb->esw.esw0.erw.cons) { 767 /* Unit check but no sense data. Need basic sense. */ 768 if (ccw_device_do_sense(cdev, irb) != 0) 769 goto call_handler_unsol; 770 memcpy(&cdev->private->dma_area->irb, irb, 771 sizeof(struct irb)); 772 cdev->private->state = DEV_STATE_W4SENSE; 773 cdev->private->intparm = 0; 774 return; 775 } 776 call_handler_unsol: 777 if (cdev->handler) 778 cdev->handler (cdev, 0, irb); 779 if (cdev->private->flags.doverify) 780 ccw_device_online_verify(cdev, 0); 781 return; 782 } 783 /* Accumulate status and find out if a basic sense is needed. */ 784 ccw_device_accumulate_irb(cdev, irb); 785 if (is_cmd && cdev->private->flags.dosense) { 786 if (ccw_device_do_sense(cdev, irb) == 0) { 787 cdev->private->state = DEV_STATE_W4SENSE; 788 } 789 return; 790 } 791 /* Call the handler. */ 792 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) 793 /* Start delayed path verification. */ 794 ccw_device_online_verify(cdev, 0); 795 } 796 797 /* 798 * Got an timeout in online state. 799 */ 800 static void 801 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event) 802 { 803 int ret; 804 805 ccw_device_set_timeout(cdev, 0); 806 cdev->private->iretry = 255; 807 cdev->private->async_kill_io_rc = -ETIMEDOUT; 808 ret = ccw_device_cancel_halt_clear(cdev); 809 if (ret == -EBUSY) { 810 ccw_device_set_timeout(cdev, 3*HZ); 811 cdev->private->state = DEV_STATE_TIMEOUT_KILL; 812 return; 813 } 814 if (ret) 815 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 816 else if (cdev->handler) 817 cdev->handler(cdev, cdev->private->intparm, 818 ERR_PTR(-ETIMEDOUT)); 819 } 820 821 /* 822 * Got an interrupt for a basic sense. 823 */ 824 static void 825 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event) 826 { 827 struct irb *irb; 828 829 irb = this_cpu_ptr(&cio_irb); 830 /* Check for unsolicited interrupt. */ 831 if (scsw_stctl(&irb->scsw) == 832 (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { 833 if (scsw_cc(&irb->scsw) == 1) 834 /* Basic sense hasn't started. Try again. */ 835 ccw_device_do_sense(cdev, irb); 836 else { 837 CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited " 838 "interrupt during w4sense...\n", 839 cdev->private->dev_id.ssid, 840 cdev->private->dev_id.devno); 841 if (cdev->handler) 842 cdev->handler (cdev, 0, irb); 843 } 844 return; 845 } 846 /* 847 * Check if a halt or clear has been issued in the meanwhile. If yes, 848 * only deliver the halt/clear interrupt to the device driver as if it 849 * had killed the original request. 850 */ 851 if (scsw_fctl(&irb->scsw) & 852 (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) { 853 cdev->private->flags.dosense = 0; 854 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb)); 855 ccw_device_accumulate_irb(cdev, irb); 856 goto call_handler; 857 } 858 /* Add basic sense info to irb. */ 859 ccw_device_accumulate_basic_sense(cdev, irb); 860 if (cdev->private->flags.dosense) { 861 /* Another basic sense is needed. */ 862 ccw_device_do_sense(cdev, irb); 863 return; 864 } 865 call_handler: 866 cdev->private->state = DEV_STATE_ONLINE; 867 /* In case sensing interfered with setting the device online */ 868 wake_up(&cdev->private->wait_q); 869 /* Call the handler. */ 870 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) 871 /* Start delayed path verification. */ 872 ccw_device_online_verify(cdev, 0); 873 } 874 875 static void 876 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event) 877 { 878 ccw_device_set_timeout(cdev, 0); 879 /* Start delayed path verification. */ 880 ccw_device_online_verify(cdev, 0); 881 /* OK, i/o is dead now. Call interrupt handler. */ 882 if (cdev->handler) 883 cdev->handler(cdev, cdev->private->intparm, 884 ERR_PTR(cdev->private->async_kill_io_rc)); 885 } 886 887 static void 888 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event) 889 { 890 int ret; 891 892 ret = ccw_device_cancel_halt_clear(cdev); 893 if (ret == -EBUSY) { 894 ccw_device_set_timeout(cdev, 3*HZ); 895 return; 896 } 897 /* Start delayed path verification. */ 898 ccw_device_online_verify(cdev, 0); 899 if (cdev->handler) 900 cdev->handler(cdev, cdev->private->intparm, 901 ERR_PTR(cdev->private->async_kill_io_rc)); 902 } 903 904 void ccw_device_kill_io(struct ccw_device *cdev) 905 { 906 int ret; 907 908 ccw_device_set_timeout(cdev, 0); 909 cdev->private->iretry = 255; 910 cdev->private->async_kill_io_rc = -EIO; 911 ret = ccw_device_cancel_halt_clear(cdev); 912 if (ret == -EBUSY) { 913 ccw_device_set_timeout(cdev, 3*HZ); 914 cdev->private->state = DEV_STATE_TIMEOUT_KILL; 915 return; 916 } 917 /* Start delayed path verification. */ 918 ccw_device_online_verify(cdev, 0); 919 if (cdev->handler) 920 cdev->handler(cdev, cdev->private->intparm, 921 ERR_PTR(-EIO)); 922 } 923 924 static void 925 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event) 926 { 927 /* Start verification after current task finished. */ 928 cdev->private->flags.doverify = 1; 929 } 930 931 static void 932 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event) 933 { 934 struct subchannel *sch; 935 936 sch = to_subchannel(cdev->dev.parent); 937 if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0) 938 /* Couldn't enable the subchannel for i/o. Sick device. */ 939 return; 940 cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID; 941 ccw_device_sense_id_start(cdev); 942 } 943 944 void ccw_device_trigger_reprobe(struct ccw_device *cdev) 945 { 946 struct subchannel *sch; 947 948 if (cdev->private->state != DEV_STATE_DISCONNECTED) 949 return; 950 951 sch = to_subchannel(cdev->dev.parent); 952 /* Update some values. */ 953 if (cio_update_schib(sch)) 954 return; 955 /* 956 * The pim, pam, pom values may not be accurate, but they are the best 957 * we have before performing device selection :/ 958 */ 959 sch->lpm = sch->schib.pmcw.pam & sch->opm; 960 /* 961 * Use the initial configuration since we can't be shure that the old 962 * paths are valid. 963 */ 964 io_subchannel_init_config(sch); 965 if (cio_commit_config(sch)) 966 return; 967 968 /* We should also udate ssd info, but this has to wait. */ 969 /* Check if this is another device which appeared on the same sch. */ 970 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) 971 css_schedule_eval(sch->schid); 972 else 973 ccw_device_start_id(cdev, 0); 974 } 975 976 static void ccw_device_disabled_irq(struct ccw_device *cdev, 977 enum dev_event dev_event) 978 { 979 struct subchannel *sch; 980 981 sch = to_subchannel(cdev->dev.parent); 982 /* 983 * An interrupt in a disabled state means a previous disable was not 984 * successful - should not happen, but we try to disable again. 985 */ 986 cio_disable_subchannel(sch); 987 } 988 989 static void 990 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event) 991 { 992 retry_set_schib(cdev); 993 cdev->private->state = DEV_STATE_ONLINE; 994 dev_fsm_event(cdev, dev_event); 995 } 996 997 static void ccw_device_update_cmfblock(struct ccw_device *cdev, 998 enum dev_event dev_event) 999 { 1000 cmf_retry_copy_block(cdev); 1001 cdev->private->state = DEV_STATE_ONLINE; 1002 dev_fsm_event(cdev, dev_event); 1003 } 1004 1005 static void 1006 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event) 1007 { 1008 ccw_device_set_timeout(cdev, 0); 1009 cdev->private->state = DEV_STATE_NOT_OPER; 1010 wake_up(&cdev->private->wait_q); 1011 } 1012 1013 static void 1014 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event) 1015 { 1016 int ret; 1017 1018 ret = ccw_device_cancel_halt_clear(cdev); 1019 if (ret == -EBUSY) { 1020 ccw_device_set_timeout(cdev, HZ/10); 1021 } else { 1022 cdev->private->state = DEV_STATE_NOT_OPER; 1023 wake_up(&cdev->private->wait_q); 1024 } 1025 } 1026 1027 /* 1028 * No operation action. This is used e.g. to ignore a timeout event in 1029 * state offline. 1030 */ 1031 static void 1032 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event) 1033 { 1034 } 1035 1036 /* 1037 * device statemachine 1038 */ 1039 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = { 1040 [DEV_STATE_NOT_OPER] = { 1041 [DEV_EVENT_NOTOPER] = ccw_device_nop, 1042 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq, 1043 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1044 [DEV_EVENT_VERIFY] = ccw_device_nop, 1045 }, 1046 [DEV_STATE_SENSE_ID] = { 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_OFFLINE] = { 1053 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1054 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq, 1055 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1056 [DEV_EVENT_VERIFY] = ccw_device_offline_verify, 1057 }, 1058 [DEV_STATE_VERIFY] = { 1059 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1060 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1061 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1062 [DEV_EVENT_VERIFY] = ccw_device_delay_verify, 1063 }, 1064 [DEV_STATE_ONLINE] = { 1065 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1066 [DEV_EVENT_INTERRUPT] = ccw_device_irq, 1067 [DEV_EVENT_TIMEOUT] = ccw_device_online_timeout, 1068 [DEV_EVENT_VERIFY] = ccw_device_online_verify, 1069 }, 1070 [DEV_STATE_W4SENSE] = { 1071 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1072 [DEV_EVENT_INTERRUPT] = ccw_device_w4sense, 1073 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1074 [DEV_EVENT_VERIFY] = ccw_device_online_verify, 1075 }, 1076 [DEV_STATE_DISBAND_PGID] = { 1077 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1078 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1079 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1080 [DEV_EVENT_VERIFY] = ccw_device_nop, 1081 }, 1082 [DEV_STATE_BOXED] = { 1083 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1084 [DEV_EVENT_INTERRUPT] = ccw_device_nop, 1085 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1086 [DEV_EVENT_VERIFY] = ccw_device_boxed_verify, 1087 }, 1088 /* states to wait for i/o completion before doing something */ 1089 [DEV_STATE_TIMEOUT_KILL] = { 1090 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1091 [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq, 1092 [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout, 1093 [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME 1094 }, 1095 [DEV_STATE_QUIESCE] = { 1096 [DEV_EVENT_NOTOPER] = ccw_device_quiesce_done, 1097 [DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done, 1098 [DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout, 1099 [DEV_EVENT_VERIFY] = ccw_device_nop, 1100 }, 1101 /* special states for devices gone not operational */ 1102 [DEV_STATE_DISCONNECTED] = { 1103 [DEV_EVENT_NOTOPER] = ccw_device_nop, 1104 [DEV_EVENT_INTERRUPT] = ccw_device_start_id, 1105 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1106 [DEV_EVENT_VERIFY] = ccw_device_start_id, 1107 }, 1108 [DEV_STATE_DISCONNECTED_SENSE_ID] = { 1109 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1110 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1111 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1112 [DEV_EVENT_VERIFY] = ccw_device_nop, 1113 }, 1114 [DEV_STATE_CMFCHANGE] = { 1115 [DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate, 1116 [DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate, 1117 [DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate, 1118 [DEV_EVENT_VERIFY] = ccw_device_change_cmfstate, 1119 }, 1120 [DEV_STATE_CMFUPDATE] = { 1121 [DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock, 1122 [DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock, 1123 [DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock, 1124 [DEV_EVENT_VERIFY] = ccw_device_update_cmfblock, 1125 }, 1126 [DEV_STATE_STEAL_LOCK] = { 1127 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1128 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1129 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1130 [DEV_EVENT_VERIFY] = ccw_device_nop, 1131 }, 1132 }; 1133 1134 EXPORT_SYMBOL_GPL(ccw_device_set_timeout); 1135