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 %lx, " 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 switch (state) { 228 case DEV_STATE_NOT_OPER: 229 break; 230 case DEV_STATE_OFFLINE: 231 if (!cdev->online) { 232 ccw_device_update_sense_data(cdev); 233 break; 234 } 235 cdev->private->state = DEV_STATE_OFFLINE; 236 cdev->private->flags.recog_done = 1; 237 if (ccw_device_test_sense_data(cdev)) { 238 cdev->private->flags.donotify = 1; 239 ccw_device_online(cdev); 240 wake_up(&cdev->private->wait_q); 241 } else { 242 ccw_device_update_sense_data(cdev); 243 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND); 244 } 245 return; 246 case DEV_STATE_BOXED: 247 if (cdev->id.cu_type != 0) { /* device was recognized before */ 248 cdev->private->flags.recog_done = 1; 249 cdev->private->state = DEV_STATE_BOXED; 250 wake_up(&cdev->private->wait_q); 251 return; 252 } 253 break; 254 } 255 cdev->private->state = state; 256 io_subchannel_recog_done(cdev); 257 wake_up(&cdev->private->wait_q); 258 } 259 260 /* 261 * Function called from device_id.c after sense id has completed. 262 */ 263 void 264 ccw_device_sense_id_done(struct ccw_device *cdev, int err) 265 { 266 switch (err) { 267 case 0: 268 ccw_device_recog_done(cdev, DEV_STATE_OFFLINE); 269 break; 270 case -ETIME: /* Sense id stopped by timeout. */ 271 ccw_device_recog_done(cdev, DEV_STATE_BOXED); 272 break; 273 default: 274 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER); 275 break; 276 } 277 } 278 279 /** 280 * ccw_device_notify() - inform the device's driver about an event 281 * @cdev: device for which an event occurred 282 * @event: event that occurred 283 * 284 * Returns: 285 * -%EINVAL if the device is offline or has no driver. 286 * -%EOPNOTSUPP if the device's driver has no notifier registered. 287 * %NOTIFY_OK if the driver wants to keep the device. 288 * %NOTIFY_BAD if the driver doesn't want to keep the device. 289 */ 290 int ccw_device_notify(struct ccw_device *cdev, int event) 291 { 292 int ret = -EINVAL; 293 294 if (!cdev->drv) 295 goto out; 296 if (!cdev->online) 297 goto out; 298 CIO_MSG_EVENT(2, "notify called for 0.%x.%04x, event=%d\n", 299 cdev->private->dev_id.ssid, cdev->private->dev_id.devno, 300 event); 301 if (!cdev->drv->notify) { 302 ret = -EOPNOTSUPP; 303 goto out; 304 } 305 if (cdev->drv->notify(cdev, event)) 306 ret = NOTIFY_OK; 307 else 308 ret = NOTIFY_BAD; 309 out: 310 return ret; 311 } 312 313 static void ccw_device_oper_notify(struct ccw_device *cdev) 314 { 315 struct subchannel *sch = to_subchannel(cdev->dev.parent); 316 317 if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_OK) { 318 /* Reenable channel measurements, if needed. */ 319 ccw_device_sched_todo(cdev, CDEV_TODO_ENABLE_CMF); 320 /* Save indication for new paths. */ 321 cdev->private->path_new_mask = sch->vpm; 322 return; 323 } 324 /* Driver doesn't want device back. */ 325 ccw_device_set_notoper(cdev); 326 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND); 327 } 328 329 /* 330 * Finished with online/offline processing. 331 */ 332 static void 333 ccw_device_done(struct ccw_device *cdev, int state) 334 { 335 struct subchannel *sch; 336 337 sch = to_subchannel(cdev->dev.parent); 338 339 ccw_device_set_timeout(cdev, 0); 340 341 if (state != DEV_STATE_ONLINE) 342 cio_disable_subchannel(sch); 343 344 /* Reset device status. */ 345 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb)); 346 347 cdev->private->state = state; 348 349 switch (state) { 350 case DEV_STATE_BOXED: 351 CIO_MSG_EVENT(0, "Boxed device %04x on subchannel %04x\n", 352 cdev->private->dev_id.devno, sch->schid.sch_no); 353 if (cdev->online && 354 ccw_device_notify(cdev, CIO_BOXED) != NOTIFY_OK) 355 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 356 cdev->private->flags.donotify = 0; 357 break; 358 case DEV_STATE_NOT_OPER: 359 CIO_MSG_EVENT(0, "Device %04x gone on subchannel %04x\n", 360 cdev->private->dev_id.devno, sch->schid.sch_no); 361 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 362 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 363 else 364 ccw_device_set_disconnected(cdev); 365 cdev->private->flags.donotify = 0; 366 break; 367 case DEV_STATE_DISCONNECTED: 368 CIO_MSG_EVENT(0, "Disconnected device %04x on subchannel " 369 "%04x\n", cdev->private->dev_id.devno, 370 sch->schid.sch_no); 371 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) { 372 cdev->private->state = DEV_STATE_NOT_OPER; 373 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 374 } else 375 ccw_device_set_disconnected(cdev); 376 cdev->private->flags.donotify = 0; 377 break; 378 default: 379 break; 380 } 381 382 if (cdev->private->flags.donotify) { 383 cdev->private->flags.donotify = 0; 384 ccw_device_oper_notify(cdev); 385 } 386 wake_up(&cdev->private->wait_q); 387 } 388 389 /* 390 * Start device recognition. 391 */ 392 void ccw_device_recognition(struct ccw_device *cdev) 393 { 394 struct subchannel *sch = to_subchannel(cdev->dev.parent); 395 396 /* 397 * We used to start here with a sense pgid to find out whether a device 398 * is locked by someone else. Unfortunately, the sense pgid command 399 * code has other meanings on devices predating the path grouping 400 * algorithm, so we start with sense id and box the device after an 401 * timeout (or if sense pgid during path verification detects the device 402 * is locked, as may happen on newer devices). 403 */ 404 cdev->private->flags.recog_done = 0; 405 cdev->private->state = DEV_STATE_SENSE_ID; 406 if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) { 407 ccw_device_recog_done(cdev, DEV_STATE_NOT_OPER); 408 return; 409 } 410 ccw_device_sense_id_start(cdev); 411 } 412 413 /* 414 * Handle events for states that use the ccw request infrastructure. 415 */ 416 static void ccw_device_request_event(struct ccw_device *cdev, enum dev_event e) 417 { 418 switch (e) { 419 case DEV_EVENT_NOTOPER: 420 ccw_request_notoper(cdev); 421 break; 422 case DEV_EVENT_INTERRUPT: 423 ccw_request_handler(cdev); 424 break; 425 case DEV_EVENT_TIMEOUT: 426 ccw_request_timeout(cdev); 427 break; 428 default: 429 break; 430 } 431 } 432 433 static void ccw_device_report_path_events(struct ccw_device *cdev) 434 { 435 struct subchannel *sch = to_subchannel(cdev->dev.parent); 436 int path_event[8]; 437 int chp, mask; 438 439 for (chp = 0, mask = 0x80; chp < 8; chp++, mask >>= 1) { 440 path_event[chp] = PE_NONE; 441 if (mask & cdev->private->path_gone_mask & ~(sch->vpm)) 442 path_event[chp] |= PE_PATH_GONE; 443 if (mask & cdev->private->path_new_mask & sch->vpm) 444 path_event[chp] |= PE_PATH_AVAILABLE; 445 if (mask & cdev->private->pgid_reset_mask & sch->vpm) 446 path_event[chp] |= PE_PATHGROUP_ESTABLISHED; 447 } 448 if (cdev->online && cdev->drv->path_event) 449 cdev->drv->path_event(cdev, path_event); 450 } 451 452 static void ccw_device_reset_path_events(struct ccw_device *cdev) 453 { 454 cdev->private->path_gone_mask = 0; 455 cdev->private->path_new_mask = 0; 456 cdev->private->pgid_reset_mask = 0; 457 } 458 459 static void create_fake_irb(struct irb *irb, int type) 460 { 461 memset(irb, 0, sizeof(*irb)); 462 if (type == FAKE_CMD_IRB) { 463 struct cmd_scsw *scsw = &irb->scsw.cmd; 464 scsw->cc = 1; 465 scsw->fctl = SCSW_FCTL_START_FUNC; 466 scsw->actl = SCSW_ACTL_START_PEND; 467 scsw->stctl = SCSW_STCTL_STATUS_PEND; 468 } else if (type == FAKE_TM_IRB) { 469 struct tm_scsw *scsw = &irb->scsw.tm; 470 scsw->x = 1; 471 scsw->cc = 1; 472 scsw->fctl = SCSW_FCTL_START_FUNC; 473 scsw->actl = SCSW_ACTL_START_PEND; 474 scsw->stctl = SCSW_STCTL_STATUS_PEND; 475 } 476 } 477 478 static void ccw_device_handle_broken_paths(struct ccw_device *cdev) 479 { 480 struct subchannel *sch = to_subchannel(cdev->dev.parent); 481 u8 broken_paths = (sch->schib.pmcw.pam & sch->opm) ^ sch->vpm; 482 483 if (broken_paths && (cdev->private->path_broken_mask != broken_paths)) 484 ccw_device_schedule_recovery(); 485 486 cdev->private->path_broken_mask = broken_paths; 487 } 488 489 void ccw_device_verify_done(struct ccw_device *cdev, int err) 490 { 491 struct subchannel *sch; 492 493 sch = to_subchannel(cdev->dev.parent); 494 /* Update schib - pom may have changed. */ 495 if (cio_update_schib(sch)) { 496 err = -ENODEV; 497 goto callback; 498 } 499 /* Update lpm with verified path mask. */ 500 sch->lpm = sch->vpm; 501 /* Repeat path verification? */ 502 if (cdev->private->flags.doverify) { 503 ccw_device_verify_start(cdev); 504 return; 505 } 506 callback: 507 switch (err) { 508 case 0: 509 ccw_device_done(cdev, DEV_STATE_ONLINE); 510 /* Deliver fake irb to device driver, if needed. */ 511 if (cdev->private->flags.fake_irb) { 512 create_fake_irb(&cdev->private->dma_area->irb, 513 cdev->private->flags.fake_irb); 514 cdev->private->flags.fake_irb = 0; 515 if (cdev->handler) 516 cdev->handler(cdev, cdev->private->intparm, 517 &cdev->private->dma_area->irb); 518 memset(&cdev->private->dma_area->irb, 0, 519 sizeof(struct irb)); 520 } 521 ccw_device_report_path_events(cdev); 522 ccw_device_handle_broken_paths(cdev); 523 break; 524 case -ETIME: 525 case -EUSERS: 526 /* Reset oper notify indication after verify error. */ 527 cdev->private->flags.donotify = 0; 528 ccw_device_done(cdev, DEV_STATE_BOXED); 529 break; 530 case -EACCES: 531 /* Reset oper notify indication after verify error. */ 532 cdev->private->flags.donotify = 0; 533 ccw_device_done(cdev, DEV_STATE_DISCONNECTED); 534 break; 535 default: 536 /* Reset oper notify indication after verify error. */ 537 cdev->private->flags.donotify = 0; 538 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 539 break; 540 } 541 ccw_device_reset_path_events(cdev); 542 } 543 544 /* 545 * Get device online. 546 */ 547 int 548 ccw_device_online(struct ccw_device *cdev) 549 { 550 struct subchannel *sch; 551 int ret; 552 553 if ((cdev->private->state != DEV_STATE_OFFLINE) && 554 (cdev->private->state != DEV_STATE_BOXED)) 555 return -EINVAL; 556 sch = to_subchannel(cdev->dev.parent); 557 ret = cio_enable_subchannel(sch, (u32)(addr_t)sch); 558 if (ret != 0) { 559 /* Couldn't enable the subchannel for i/o. Sick device. */ 560 if (ret == -ENODEV) 561 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 562 return ret; 563 } 564 /* Start initial path verification. */ 565 cdev->private->state = DEV_STATE_VERIFY; 566 ccw_device_verify_start(cdev); 567 return 0; 568 } 569 570 void 571 ccw_device_disband_done(struct ccw_device *cdev, int err) 572 { 573 switch (err) { 574 case 0: 575 ccw_device_done(cdev, DEV_STATE_OFFLINE); 576 break; 577 case -ETIME: 578 ccw_device_done(cdev, DEV_STATE_BOXED); 579 break; 580 default: 581 cdev->private->flags.donotify = 0; 582 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 583 break; 584 } 585 } 586 587 /* 588 * Shutdown device. 589 */ 590 int 591 ccw_device_offline(struct ccw_device *cdev) 592 { 593 struct subchannel *sch; 594 595 /* Allow ccw_device_offline while disconnected. */ 596 if (cdev->private->state == DEV_STATE_DISCONNECTED || 597 cdev->private->state == DEV_STATE_NOT_OPER) { 598 cdev->private->flags.donotify = 0; 599 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 600 return 0; 601 } 602 if (cdev->private->state == DEV_STATE_BOXED) { 603 ccw_device_done(cdev, DEV_STATE_BOXED); 604 return 0; 605 } 606 if (ccw_device_is_orphan(cdev)) { 607 ccw_device_done(cdev, DEV_STATE_OFFLINE); 608 return 0; 609 } 610 sch = to_subchannel(cdev->dev.parent); 611 if (cio_update_schib(sch)) 612 return -ENODEV; 613 if (scsw_actl(&sch->schib.scsw) != 0) 614 return -EBUSY; 615 if (cdev->private->state != DEV_STATE_ONLINE) 616 return -EINVAL; 617 /* Are we doing path grouping? */ 618 if (!cdev->private->flags.pgroup) { 619 /* No, set state offline immediately. */ 620 ccw_device_done(cdev, DEV_STATE_OFFLINE); 621 return 0; 622 } 623 /* Start Set Path Group commands. */ 624 cdev->private->state = DEV_STATE_DISBAND_PGID; 625 ccw_device_disband_start(cdev); 626 return 0; 627 } 628 629 /* 630 * Handle not operational event in non-special state. 631 */ 632 static void ccw_device_generic_notoper(struct ccw_device *cdev, 633 enum dev_event dev_event) 634 { 635 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 636 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 637 else 638 ccw_device_set_disconnected(cdev); 639 } 640 641 /* 642 * Handle path verification event in offline state. 643 */ 644 static void ccw_device_offline_verify(struct ccw_device *cdev, 645 enum dev_event dev_event) 646 { 647 struct subchannel *sch = to_subchannel(cdev->dev.parent); 648 649 css_schedule_eval(sch->schid); 650 } 651 652 /* 653 * Handle path verification event. 654 */ 655 static void 656 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event) 657 { 658 struct subchannel *sch; 659 660 if (cdev->private->state == DEV_STATE_W4SENSE) { 661 cdev->private->flags.doverify = 1; 662 return; 663 } 664 sch = to_subchannel(cdev->dev.parent); 665 /* 666 * Since we might not just be coming from an interrupt from the 667 * subchannel we have to update the schib. 668 */ 669 if (cio_update_schib(sch)) { 670 ccw_device_verify_done(cdev, -ENODEV); 671 return; 672 } 673 674 if (scsw_actl(&sch->schib.scsw) != 0 || 675 (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) || 676 (scsw_stctl(&cdev->private->dma_area->irb.scsw) & 677 SCSW_STCTL_STATUS_PEND)) { 678 /* 679 * No final status yet or final status not yet delivered 680 * to the device driver. Can't do path verification now, 681 * delay until final status was delivered. 682 */ 683 cdev->private->flags.doverify = 1; 684 return; 685 } 686 /* Device is idle, we can do the path verification. */ 687 cdev->private->state = DEV_STATE_VERIFY; 688 ccw_device_verify_start(cdev); 689 } 690 691 /* 692 * Handle path verification event in boxed state. 693 */ 694 static void ccw_device_boxed_verify(struct ccw_device *cdev, 695 enum dev_event dev_event) 696 { 697 struct subchannel *sch = to_subchannel(cdev->dev.parent); 698 699 if (cdev->online) { 700 if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) 701 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 702 else 703 ccw_device_online_verify(cdev, dev_event); 704 } else 705 css_schedule_eval(sch->schid); 706 } 707 708 /* 709 * Pass interrupt to device driver. 710 */ 711 static int ccw_device_call_handler(struct ccw_device *cdev) 712 { 713 unsigned int stctl; 714 int ending_status; 715 716 /* 717 * we allow for the device action handler if . 718 * - we received ending status 719 * - the action handler requested to see all interrupts 720 * - we received an intermediate status 721 * - fast notification was requested (primary status) 722 * - unsolicited interrupts 723 */ 724 stctl = scsw_stctl(&cdev->private->dma_area->irb.scsw); 725 ending_status = (stctl & SCSW_STCTL_SEC_STATUS) || 726 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) || 727 (stctl == SCSW_STCTL_STATUS_PEND); 728 if (!ending_status && 729 !cdev->private->options.repall && 730 !(stctl & SCSW_STCTL_INTER_STATUS) && 731 !(cdev->private->options.fast && 732 (stctl & SCSW_STCTL_PRIM_STATUS))) 733 return 0; 734 735 if (ending_status) 736 ccw_device_set_timeout(cdev, 0); 737 738 if (cdev->handler) 739 cdev->handler(cdev, cdev->private->intparm, 740 &cdev->private->dma_area->irb); 741 742 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb)); 743 return 1; 744 } 745 746 /* 747 * Got an interrupt for a normal io (state online). 748 */ 749 static void 750 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event) 751 { 752 struct irb *irb; 753 int is_cmd; 754 755 irb = this_cpu_ptr(&cio_irb); 756 is_cmd = !scsw_is_tm(&irb->scsw); 757 /* Check for unsolicited interrupt. */ 758 if (!scsw_is_solicited(&irb->scsw)) { 759 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) && 760 !irb->esw.esw0.erw.cons) { 761 /* Unit check but no sense data. Need basic sense. */ 762 if (ccw_device_do_sense(cdev, irb) != 0) 763 goto call_handler_unsol; 764 memcpy(&cdev->private->dma_area->irb, irb, 765 sizeof(struct irb)); 766 cdev->private->state = DEV_STATE_W4SENSE; 767 cdev->private->intparm = 0; 768 return; 769 } 770 call_handler_unsol: 771 if (cdev->handler) 772 cdev->handler (cdev, 0, irb); 773 if (cdev->private->flags.doverify) 774 ccw_device_online_verify(cdev, 0); 775 return; 776 } 777 /* Accumulate status and find out if a basic sense is needed. */ 778 ccw_device_accumulate_irb(cdev, irb); 779 if (is_cmd && cdev->private->flags.dosense) { 780 if (ccw_device_do_sense(cdev, irb) == 0) { 781 cdev->private->state = DEV_STATE_W4SENSE; 782 } 783 return; 784 } 785 /* Call the handler. */ 786 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) 787 /* Start delayed path verification. */ 788 ccw_device_online_verify(cdev, 0); 789 } 790 791 /* 792 * Got an timeout in online state. 793 */ 794 static void 795 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event) 796 { 797 int ret; 798 799 ccw_device_set_timeout(cdev, 0); 800 cdev->private->iretry = 255; 801 cdev->private->async_kill_io_rc = -ETIMEDOUT; 802 ret = ccw_device_cancel_halt_clear(cdev); 803 if (ret == -EBUSY) { 804 ccw_device_set_timeout(cdev, 3*HZ); 805 cdev->private->state = DEV_STATE_TIMEOUT_KILL; 806 return; 807 } 808 if (ret) 809 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 810 else if (cdev->handler) 811 cdev->handler(cdev, cdev->private->intparm, 812 ERR_PTR(-ETIMEDOUT)); 813 } 814 815 /* 816 * Got an interrupt for a basic sense. 817 */ 818 static void 819 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event) 820 { 821 struct irb *irb; 822 823 irb = this_cpu_ptr(&cio_irb); 824 /* Check for unsolicited interrupt. */ 825 if (scsw_stctl(&irb->scsw) == 826 (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { 827 if (scsw_cc(&irb->scsw) == 1) 828 /* Basic sense hasn't started. Try again. */ 829 ccw_device_do_sense(cdev, irb); 830 else { 831 CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited " 832 "interrupt during w4sense...\n", 833 cdev->private->dev_id.ssid, 834 cdev->private->dev_id.devno); 835 if (cdev->handler) 836 cdev->handler (cdev, 0, irb); 837 } 838 return; 839 } 840 /* 841 * Check if a halt or clear has been issued in the meanwhile. If yes, 842 * only deliver the halt/clear interrupt to the device driver as if it 843 * had killed the original request. 844 */ 845 if (scsw_fctl(&irb->scsw) & 846 (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) { 847 cdev->private->flags.dosense = 0; 848 memset(&cdev->private->dma_area->irb, 0, sizeof(struct irb)); 849 ccw_device_accumulate_irb(cdev, irb); 850 goto call_handler; 851 } 852 /* Add basic sense info to irb. */ 853 ccw_device_accumulate_basic_sense(cdev, irb); 854 if (cdev->private->flags.dosense) { 855 /* Another basic sense is needed. */ 856 ccw_device_do_sense(cdev, irb); 857 return; 858 } 859 call_handler: 860 cdev->private->state = DEV_STATE_ONLINE; 861 /* In case sensing interfered with setting the device online */ 862 wake_up(&cdev->private->wait_q); 863 /* Call the handler. */ 864 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) 865 /* Start delayed path verification. */ 866 ccw_device_online_verify(cdev, 0); 867 } 868 869 static void 870 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event) 871 { 872 ccw_device_set_timeout(cdev, 0); 873 /* Start delayed path verification. */ 874 ccw_device_online_verify(cdev, 0); 875 /* OK, i/o is dead now. Call interrupt handler. */ 876 if (cdev->handler) 877 cdev->handler(cdev, cdev->private->intparm, 878 ERR_PTR(cdev->private->async_kill_io_rc)); 879 } 880 881 static void 882 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event) 883 { 884 int ret; 885 886 ret = ccw_device_cancel_halt_clear(cdev); 887 if (ret == -EBUSY) { 888 ccw_device_set_timeout(cdev, 3*HZ); 889 return; 890 } 891 /* Start delayed path verification. */ 892 ccw_device_online_verify(cdev, 0); 893 if (cdev->handler) 894 cdev->handler(cdev, cdev->private->intparm, 895 ERR_PTR(cdev->private->async_kill_io_rc)); 896 } 897 898 void ccw_device_kill_io(struct ccw_device *cdev) 899 { 900 int ret; 901 902 ccw_device_set_timeout(cdev, 0); 903 cdev->private->iretry = 255; 904 cdev->private->async_kill_io_rc = -EIO; 905 ret = ccw_device_cancel_halt_clear(cdev); 906 if (ret == -EBUSY) { 907 ccw_device_set_timeout(cdev, 3*HZ); 908 cdev->private->state = DEV_STATE_TIMEOUT_KILL; 909 return; 910 } 911 /* Start delayed path verification. */ 912 ccw_device_online_verify(cdev, 0); 913 if (cdev->handler) 914 cdev->handler(cdev, cdev->private->intparm, 915 ERR_PTR(-EIO)); 916 } 917 918 static void 919 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event) 920 { 921 /* Start verification after current task finished. */ 922 cdev->private->flags.doverify = 1; 923 } 924 925 static void 926 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event) 927 { 928 struct subchannel *sch; 929 930 sch = to_subchannel(cdev->dev.parent); 931 if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0) 932 /* Couldn't enable the subchannel for i/o. Sick device. */ 933 return; 934 cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID; 935 ccw_device_sense_id_start(cdev); 936 } 937 938 void ccw_device_trigger_reprobe(struct ccw_device *cdev) 939 { 940 struct subchannel *sch; 941 942 if (cdev->private->state != DEV_STATE_DISCONNECTED) 943 return; 944 945 sch = to_subchannel(cdev->dev.parent); 946 /* Update some values. */ 947 if (cio_update_schib(sch)) 948 return; 949 /* 950 * The pim, pam, pom values may not be accurate, but they are the best 951 * we have before performing device selection :/ 952 */ 953 sch->lpm = sch->schib.pmcw.pam & sch->opm; 954 /* 955 * Use the initial configuration since we can't be shure that the old 956 * paths are valid. 957 */ 958 io_subchannel_init_config(sch); 959 if (cio_commit_config(sch)) 960 return; 961 962 /* We should also udate ssd info, but this has to wait. */ 963 /* Check if this is another device which appeared on the same sch. */ 964 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) 965 css_schedule_eval(sch->schid); 966 else 967 ccw_device_start_id(cdev, 0); 968 } 969 970 static void ccw_device_disabled_irq(struct ccw_device *cdev, 971 enum dev_event dev_event) 972 { 973 struct subchannel *sch; 974 975 sch = to_subchannel(cdev->dev.parent); 976 /* 977 * An interrupt in a disabled state means a previous disable was not 978 * successful - should not happen, but we try to disable again. 979 */ 980 cio_disable_subchannel(sch); 981 } 982 983 static void 984 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event) 985 { 986 retry_set_schib(cdev); 987 cdev->private->state = DEV_STATE_ONLINE; 988 dev_fsm_event(cdev, dev_event); 989 } 990 991 static void ccw_device_update_cmfblock(struct ccw_device *cdev, 992 enum dev_event dev_event) 993 { 994 cmf_retry_copy_block(cdev); 995 cdev->private->state = DEV_STATE_ONLINE; 996 dev_fsm_event(cdev, dev_event); 997 } 998 999 static void 1000 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event) 1001 { 1002 ccw_device_set_timeout(cdev, 0); 1003 cdev->private->state = DEV_STATE_NOT_OPER; 1004 wake_up(&cdev->private->wait_q); 1005 } 1006 1007 static void 1008 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event) 1009 { 1010 int ret; 1011 1012 ret = ccw_device_cancel_halt_clear(cdev); 1013 if (ret == -EBUSY) { 1014 ccw_device_set_timeout(cdev, HZ/10); 1015 } else { 1016 cdev->private->state = DEV_STATE_NOT_OPER; 1017 wake_up(&cdev->private->wait_q); 1018 } 1019 } 1020 1021 /* 1022 * No operation action. This is used e.g. to ignore a timeout event in 1023 * state offline. 1024 */ 1025 static void 1026 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event) 1027 { 1028 } 1029 1030 /* 1031 * device statemachine 1032 */ 1033 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = { 1034 [DEV_STATE_NOT_OPER] = { 1035 [DEV_EVENT_NOTOPER] = ccw_device_nop, 1036 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq, 1037 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1038 [DEV_EVENT_VERIFY] = ccw_device_nop, 1039 }, 1040 [DEV_STATE_SENSE_ID] = { 1041 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1042 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1043 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1044 [DEV_EVENT_VERIFY] = ccw_device_nop, 1045 }, 1046 [DEV_STATE_OFFLINE] = { 1047 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1048 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq, 1049 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1050 [DEV_EVENT_VERIFY] = ccw_device_offline_verify, 1051 }, 1052 [DEV_STATE_VERIFY] = { 1053 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1054 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1055 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1056 [DEV_EVENT_VERIFY] = ccw_device_delay_verify, 1057 }, 1058 [DEV_STATE_ONLINE] = { 1059 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1060 [DEV_EVENT_INTERRUPT] = ccw_device_irq, 1061 [DEV_EVENT_TIMEOUT] = ccw_device_online_timeout, 1062 [DEV_EVENT_VERIFY] = ccw_device_online_verify, 1063 }, 1064 [DEV_STATE_W4SENSE] = { 1065 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1066 [DEV_EVENT_INTERRUPT] = ccw_device_w4sense, 1067 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1068 [DEV_EVENT_VERIFY] = ccw_device_online_verify, 1069 }, 1070 [DEV_STATE_DISBAND_PGID] = { 1071 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1072 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1073 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1074 [DEV_EVENT_VERIFY] = ccw_device_nop, 1075 }, 1076 [DEV_STATE_BOXED] = { 1077 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1078 [DEV_EVENT_INTERRUPT] = ccw_device_nop, 1079 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1080 [DEV_EVENT_VERIFY] = ccw_device_boxed_verify, 1081 }, 1082 /* states to wait for i/o completion before doing something */ 1083 [DEV_STATE_TIMEOUT_KILL] = { 1084 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1085 [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq, 1086 [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout, 1087 [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME 1088 }, 1089 [DEV_STATE_QUIESCE] = { 1090 [DEV_EVENT_NOTOPER] = ccw_device_quiesce_done, 1091 [DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done, 1092 [DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout, 1093 [DEV_EVENT_VERIFY] = ccw_device_nop, 1094 }, 1095 /* special states for devices gone not operational */ 1096 [DEV_STATE_DISCONNECTED] = { 1097 [DEV_EVENT_NOTOPER] = ccw_device_nop, 1098 [DEV_EVENT_INTERRUPT] = ccw_device_start_id, 1099 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1100 [DEV_EVENT_VERIFY] = ccw_device_start_id, 1101 }, 1102 [DEV_STATE_DISCONNECTED_SENSE_ID] = { 1103 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1104 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1105 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1106 [DEV_EVENT_VERIFY] = ccw_device_nop, 1107 }, 1108 [DEV_STATE_CMFCHANGE] = { 1109 [DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate, 1110 [DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate, 1111 [DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate, 1112 [DEV_EVENT_VERIFY] = ccw_device_change_cmfstate, 1113 }, 1114 [DEV_STATE_CMFUPDATE] = { 1115 [DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock, 1116 [DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock, 1117 [DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock, 1118 [DEV_EVENT_VERIFY] = ccw_device_update_cmfblock, 1119 }, 1120 [DEV_STATE_STEAL_LOCK] = { 1121 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1122 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1123 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1124 [DEV_EVENT_VERIFY] = ccw_device_nop, 1125 }, 1126 }; 1127 1128 EXPORT_SYMBOL_GPL(ccw_device_set_timeout); 1129