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 == &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 void 96 ccw_device_timeout(struct timer_list *t) 97 { 98 struct ccw_device_private *priv = from_timer(priv, t, timer); 99 struct ccw_device *cdev = priv->cdev; 100 101 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.expires = jiffies + expires; 123 add_timer(&cdev->private->timer); 124 } 125 126 int 127 ccw_device_cancel_halt_clear(struct ccw_device *cdev) 128 { 129 struct subchannel *sch; 130 int ret; 131 132 sch = to_subchannel(cdev->dev.parent); 133 ret = cio_cancel_halt_clear(sch, &cdev->private->iretry); 134 135 if (ret == -EIO) 136 CIO_MSG_EVENT(0, "0.%x.%04x: could not stop I/O\n", 137 cdev->private->dev_id.ssid, 138 cdev->private->dev_id.devno); 139 140 return ret; 141 } 142 143 void ccw_device_update_sense_data(struct ccw_device *cdev) 144 { 145 memset(&cdev->id, 0, sizeof(cdev->id)); 146 cdev->id.cu_type = cdev->private->senseid.cu_type; 147 cdev->id.cu_model = cdev->private->senseid.cu_model; 148 cdev->id.dev_type = cdev->private->senseid.dev_type; 149 cdev->id.dev_model = cdev->private->senseid.dev_model; 150 } 151 152 int ccw_device_test_sense_data(struct ccw_device *cdev) 153 { 154 return cdev->id.cu_type == cdev->private->senseid.cu_type && 155 cdev->id.cu_model == cdev->private->senseid.cu_model && 156 cdev->id.dev_type == cdev->private->senseid.dev_type && 157 cdev->id.dev_model == cdev->private->senseid.dev_model; 158 } 159 160 /* 161 * The machine won't give us any notification by machine check if a chpid has 162 * been varied online on the SE so we have to find out by magic (i. e. driving 163 * the channel subsystem to device selection and updating our path masks). 164 */ 165 static void 166 __recover_lost_chpids(struct subchannel *sch, int old_lpm) 167 { 168 int mask, i; 169 struct chp_id chpid; 170 171 chp_id_init(&chpid); 172 for (i = 0; i<8; i++) { 173 mask = 0x80 >> i; 174 if (!(sch->lpm & mask)) 175 continue; 176 if (old_lpm & mask) 177 continue; 178 chpid.id = sch->schib.pmcw.chpid[i]; 179 if (!chp_is_registered(chpid)) 180 css_schedule_eval_all(); 181 } 182 } 183 184 /* 185 * Stop device recognition. 186 */ 187 static void 188 ccw_device_recog_done(struct ccw_device *cdev, int state) 189 { 190 struct subchannel *sch; 191 int old_lpm; 192 193 sch = to_subchannel(cdev->dev.parent); 194 195 if (cio_disable_subchannel(sch)) 196 state = DEV_STATE_NOT_OPER; 197 /* 198 * Now that we tried recognition, we have performed device selection 199 * through ssch() and the path information is up to date. 200 */ 201 old_lpm = sch->lpm; 202 203 /* Check since device may again have become not operational. */ 204 if (cio_update_schib(sch)) 205 state = DEV_STATE_NOT_OPER; 206 else 207 sch->lpm = sch->schib.pmcw.pam & sch->opm; 208 209 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID) 210 /* Force reprobe on all chpids. */ 211 old_lpm = 0; 212 if (sch->lpm != old_lpm) 213 __recover_lost_chpids(sch, old_lpm); 214 if (cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID && 215 (state == DEV_STATE_NOT_OPER || state == DEV_STATE_BOXED)) { 216 cdev->private->flags.recog_done = 1; 217 cdev->private->state = DEV_STATE_DISCONNECTED; 218 wake_up(&cdev->private->wait_q); 219 return; 220 } 221 if (cdev->private->flags.resuming) { 222 cdev->private->state = state; 223 cdev->private->flags.recog_done = 1; 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->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->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->irb); 518 memset(&cdev->private->irb, 0, sizeof(struct irb)); 519 } 520 ccw_device_report_path_events(cdev); 521 ccw_device_handle_broken_paths(cdev); 522 break; 523 case -ETIME: 524 case -EUSERS: 525 /* Reset oper notify indication after verify error. */ 526 cdev->private->flags.donotify = 0; 527 ccw_device_done(cdev, DEV_STATE_BOXED); 528 break; 529 case -EACCES: 530 /* Reset oper notify indication after verify error. */ 531 cdev->private->flags.donotify = 0; 532 ccw_device_done(cdev, DEV_STATE_DISCONNECTED); 533 break; 534 default: 535 /* Reset oper notify indication after verify error. */ 536 cdev->private->flags.donotify = 0; 537 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 538 break; 539 } 540 ccw_device_reset_path_events(cdev); 541 } 542 543 /* 544 * Get device online. 545 */ 546 int 547 ccw_device_online(struct ccw_device *cdev) 548 { 549 struct subchannel *sch; 550 int ret; 551 552 if ((cdev->private->state != DEV_STATE_OFFLINE) && 553 (cdev->private->state != DEV_STATE_BOXED)) 554 return -EINVAL; 555 sch = to_subchannel(cdev->dev.parent); 556 ret = cio_enable_subchannel(sch, (u32)(addr_t)sch); 557 if (ret != 0) { 558 /* Couldn't enable the subchannel for i/o. Sick device. */ 559 if (ret == -ENODEV) 560 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 561 return ret; 562 } 563 /* Start initial path verification. */ 564 cdev->private->state = DEV_STATE_VERIFY; 565 ccw_device_verify_start(cdev); 566 return 0; 567 } 568 569 void 570 ccw_device_disband_done(struct ccw_device *cdev, int err) 571 { 572 switch (err) { 573 case 0: 574 ccw_device_done(cdev, DEV_STATE_OFFLINE); 575 break; 576 case -ETIME: 577 ccw_device_done(cdev, DEV_STATE_BOXED); 578 break; 579 default: 580 cdev->private->flags.donotify = 0; 581 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 582 break; 583 } 584 } 585 586 /* 587 * Shutdown device. 588 */ 589 int 590 ccw_device_offline(struct ccw_device *cdev) 591 { 592 struct subchannel *sch; 593 594 /* Allow ccw_device_offline while disconnected. */ 595 if (cdev->private->state == DEV_STATE_DISCONNECTED || 596 cdev->private->state == DEV_STATE_NOT_OPER) { 597 cdev->private->flags.donotify = 0; 598 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 599 return 0; 600 } 601 if (cdev->private->state == DEV_STATE_BOXED) { 602 ccw_device_done(cdev, DEV_STATE_BOXED); 603 return 0; 604 } 605 if (ccw_device_is_orphan(cdev)) { 606 ccw_device_done(cdev, DEV_STATE_OFFLINE); 607 return 0; 608 } 609 sch = to_subchannel(cdev->dev.parent); 610 if (cio_update_schib(sch)) 611 return -ENODEV; 612 if (scsw_actl(&sch->schib.scsw) != 0) 613 return -EBUSY; 614 if (cdev->private->state != DEV_STATE_ONLINE) 615 return -EINVAL; 616 /* Are we doing path grouping? */ 617 if (!cdev->private->flags.pgroup) { 618 /* No, set state offline immediately. */ 619 ccw_device_done(cdev, DEV_STATE_OFFLINE); 620 return 0; 621 } 622 /* Start Set Path Group commands. */ 623 cdev->private->state = DEV_STATE_DISBAND_PGID; 624 ccw_device_disband_start(cdev); 625 return 0; 626 } 627 628 /* 629 * Handle not operational event in non-special state. 630 */ 631 static void ccw_device_generic_notoper(struct ccw_device *cdev, 632 enum dev_event dev_event) 633 { 634 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 635 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 636 else 637 ccw_device_set_disconnected(cdev); 638 } 639 640 /* 641 * Handle path verification event in offline state. 642 */ 643 static void ccw_device_offline_verify(struct ccw_device *cdev, 644 enum dev_event dev_event) 645 { 646 struct subchannel *sch = to_subchannel(cdev->dev.parent); 647 648 css_schedule_eval(sch->schid); 649 } 650 651 /* 652 * Handle path verification event. 653 */ 654 static void 655 ccw_device_online_verify(struct ccw_device *cdev, enum dev_event dev_event) 656 { 657 struct subchannel *sch; 658 659 if (cdev->private->state == DEV_STATE_W4SENSE) { 660 cdev->private->flags.doverify = 1; 661 return; 662 } 663 sch = to_subchannel(cdev->dev.parent); 664 /* 665 * Since we might not just be coming from an interrupt from the 666 * subchannel we have to update the schib. 667 */ 668 if (cio_update_schib(sch)) { 669 ccw_device_verify_done(cdev, -ENODEV); 670 return; 671 } 672 673 if (scsw_actl(&sch->schib.scsw) != 0 || 674 (scsw_stctl(&sch->schib.scsw) & SCSW_STCTL_STATUS_PEND) || 675 (scsw_stctl(&cdev->private->irb.scsw) & SCSW_STCTL_STATUS_PEND)) { 676 /* 677 * No final status yet or final status not yet delivered 678 * to the device driver. Can't do path verification now, 679 * delay until final status was delivered. 680 */ 681 cdev->private->flags.doverify = 1; 682 return; 683 } 684 /* Device is idle, we can do the path verification. */ 685 cdev->private->state = DEV_STATE_VERIFY; 686 ccw_device_verify_start(cdev); 687 } 688 689 /* 690 * Handle path verification event in boxed state. 691 */ 692 static void ccw_device_boxed_verify(struct ccw_device *cdev, 693 enum dev_event dev_event) 694 { 695 struct subchannel *sch = to_subchannel(cdev->dev.parent); 696 697 if (cdev->online) { 698 if (cio_enable_subchannel(sch, (u32) (addr_t) sch)) 699 ccw_device_done(cdev, DEV_STATE_NOT_OPER); 700 else 701 ccw_device_online_verify(cdev, dev_event); 702 } else 703 css_schedule_eval(sch->schid); 704 } 705 706 /* 707 * Pass interrupt to device driver. 708 */ 709 static int ccw_device_call_handler(struct ccw_device *cdev) 710 { 711 unsigned int stctl; 712 int ending_status; 713 714 /* 715 * we allow for the device action handler if . 716 * - we received ending status 717 * - the action handler requested to see all interrupts 718 * - we received an intermediate status 719 * - fast notification was requested (primary status) 720 * - unsolicited interrupts 721 */ 722 stctl = scsw_stctl(&cdev->private->irb.scsw); 723 ending_status = (stctl & SCSW_STCTL_SEC_STATUS) || 724 (stctl == (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND)) || 725 (stctl == SCSW_STCTL_STATUS_PEND); 726 if (!ending_status && 727 !cdev->private->options.repall && 728 !(stctl & SCSW_STCTL_INTER_STATUS) && 729 !(cdev->private->options.fast && 730 (stctl & SCSW_STCTL_PRIM_STATUS))) 731 return 0; 732 733 if (ending_status) 734 ccw_device_set_timeout(cdev, 0); 735 736 if (cdev->handler) 737 cdev->handler(cdev, cdev->private->intparm, 738 &cdev->private->irb); 739 740 memset(&cdev->private->irb, 0, sizeof(struct irb)); 741 return 1; 742 } 743 744 /* 745 * Got an interrupt for a normal io (state online). 746 */ 747 static void 748 ccw_device_irq(struct ccw_device *cdev, enum dev_event dev_event) 749 { 750 struct irb *irb; 751 int is_cmd; 752 753 irb = this_cpu_ptr(&cio_irb); 754 is_cmd = !scsw_is_tm(&irb->scsw); 755 /* Check for unsolicited interrupt. */ 756 if (!scsw_is_solicited(&irb->scsw)) { 757 if (is_cmd && (irb->scsw.cmd.dstat & DEV_STAT_UNIT_CHECK) && 758 !irb->esw.esw0.erw.cons) { 759 /* Unit check but no sense data. Need basic sense. */ 760 if (ccw_device_do_sense(cdev, irb) != 0) 761 goto call_handler_unsol; 762 memcpy(&cdev->private->irb, irb, sizeof(struct irb)); 763 cdev->private->state = DEV_STATE_W4SENSE; 764 cdev->private->intparm = 0; 765 return; 766 } 767 call_handler_unsol: 768 if (cdev->handler) 769 cdev->handler (cdev, 0, irb); 770 if (cdev->private->flags.doverify) 771 ccw_device_online_verify(cdev, 0); 772 return; 773 } 774 /* Accumulate status and find out if a basic sense is needed. */ 775 ccw_device_accumulate_irb(cdev, irb); 776 if (is_cmd && cdev->private->flags.dosense) { 777 if (ccw_device_do_sense(cdev, irb) == 0) { 778 cdev->private->state = DEV_STATE_W4SENSE; 779 } 780 return; 781 } 782 /* Call the handler. */ 783 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) 784 /* Start delayed path verification. */ 785 ccw_device_online_verify(cdev, 0); 786 } 787 788 /* 789 * Got an timeout in online state. 790 */ 791 static void 792 ccw_device_online_timeout(struct ccw_device *cdev, enum dev_event dev_event) 793 { 794 int ret; 795 796 ccw_device_set_timeout(cdev, 0); 797 cdev->private->iretry = 255; 798 ret = ccw_device_cancel_halt_clear(cdev); 799 if (ret == -EBUSY) { 800 ccw_device_set_timeout(cdev, 3*HZ); 801 cdev->private->state = DEV_STATE_TIMEOUT_KILL; 802 return; 803 } 804 if (ret) 805 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 806 else if (cdev->handler) 807 cdev->handler(cdev, cdev->private->intparm, 808 ERR_PTR(-ETIMEDOUT)); 809 } 810 811 /* 812 * Got an interrupt for a basic sense. 813 */ 814 static void 815 ccw_device_w4sense(struct ccw_device *cdev, enum dev_event dev_event) 816 { 817 struct irb *irb; 818 819 irb = this_cpu_ptr(&cio_irb); 820 /* Check for unsolicited interrupt. */ 821 if (scsw_stctl(&irb->scsw) == 822 (SCSW_STCTL_STATUS_PEND | SCSW_STCTL_ALERT_STATUS)) { 823 if (scsw_cc(&irb->scsw) == 1) 824 /* Basic sense hasn't started. Try again. */ 825 ccw_device_do_sense(cdev, irb); 826 else { 827 CIO_MSG_EVENT(0, "0.%x.%04x: unsolicited " 828 "interrupt during w4sense...\n", 829 cdev->private->dev_id.ssid, 830 cdev->private->dev_id.devno); 831 if (cdev->handler) 832 cdev->handler (cdev, 0, irb); 833 } 834 return; 835 } 836 /* 837 * Check if a halt or clear has been issued in the meanwhile. If yes, 838 * only deliver the halt/clear interrupt to the device driver as if it 839 * had killed the original request. 840 */ 841 if (scsw_fctl(&irb->scsw) & 842 (SCSW_FCTL_CLEAR_FUNC | SCSW_FCTL_HALT_FUNC)) { 843 cdev->private->flags.dosense = 0; 844 memset(&cdev->private->irb, 0, sizeof(struct irb)); 845 ccw_device_accumulate_irb(cdev, irb); 846 goto call_handler; 847 } 848 /* Add basic sense info to irb. */ 849 ccw_device_accumulate_basic_sense(cdev, irb); 850 if (cdev->private->flags.dosense) { 851 /* Another basic sense is needed. */ 852 ccw_device_do_sense(cdev, irb); 853 return; 854 } 855 call_handler: 856 cdev->private->state = DEV_STATE_ONLINE; 857 /* In case sensing interfered with setting the device online */ 858 wake_up(&cdev->private->wait_q); 859 /* Call the handler. */ 860 if (ccw_device_call_handler(cdev) && cdev->private->flags.doverify) 861 /* Start delayed path verification. */ 862 ccw_device_online_verify(cdev, 0); 863 } 864 865 static void 866 ccw_device_killing_irq(struct ccw_device *cdev, enum dev_event dev_event) 867 { 868 ccw_device_set_timeout(cdev, 0); 869 /* Start delayed path verification. */ 870 ccw_device_online_verify(cdev, 0); 871 /* OK, i/o is dead now. Call interrupt handler. */ 872 if (cdev->handler) 873 cdev->handler(cdev, cdev->private->intparm, 874 ERR_PTR(-EIO)); 875 } 876 877 static void 878 ccw_device_killing_timeout(struct ccw_device *cdev, enum dev_event dev_event) 879 { 880 int ret; 881 882 ret = ccw_device_cancel_halt_clear(cdev); 883 if (ret == -EBUSY) { 884 ccw_device_set_timeout(cdev, 3*HZ); 885 return; 886 } 887 /* Start delayed path verification. */ 888 ccw_device_online_verify(cdev, 0); 889 if (cdev->handler) 890 cdev->handler(cdev, cdev->private->intparm, 891 ERR_PTR(-EIO)); 892 } 893 894 void ccw_device_kill_io(struct ccw_device *cdev) 895 { 896 int ret; 897 898 cdev->private->iretry = 255; 899 ret = ccw_device_cancel_halt_clear(cdev); 900 if (ret == -EBUSY) { 901 ccw_device_set_timeout(cdev, 3*HZ); 902 cdev->private->state = DEV_STATE_TIMEOUT_KILL; 903 return; 904 } 905 /* Start delayed path verification. */ 906 ccw_device_online_verify(cdev, 0); 907 if (cdev->handler) 908 cdev->handler(cdev, cdev->private->intparm, 909 ERR_PTR(-EIO)); 910 } 911 912 static void 913 ccw_device_delay_verify(struct ccw_device *cdev, enum dev_event dev_event) 914 { 915 /* Start verification after current task finished. */ 916 cdev->private->flags.doverify = 1; 917 } 918 919 static void 920 ccw_device_start_id(struct ccw_device *cdev, enum dev_event dev_event) 921 { 922 struct subchannel *sch; 923 924 sch = to_subchannel(cdev->dev.parent); 925 if (cio_enable_subchannel(sch, (u32)(addr_t)sch) != 0) 926 /* Couldn't enable the subchannel for i/o. Sick device. */ 927 return; 928 cdev->private->state = DEV_STATE_DISCONNECTED_SENSE_ID; 929 ccw_device_sense_id_start(cdev); 930 } 931 932 void ccw_device_trigger_reprobe(struct ccw_device *cdev) 933 { 934 struct subchannel *sch; 935 936 if (cdev->private->state != DEV_STATE_DISCONNECTED) 937 return; 938 939 sch = to_subchannel(cdev->dev.parent); 940 /* Update some values. */ 941 if (cio_update_schib(sch)) 942 return; 943 /* 944 * The pim, pam, pom values may not be accurate, but they are the best 945 * we have before performing device selection :/ 946 */ 947 sch->lpm = sch->schib.pmcw.pam & sch->opm; 948 /* 949 * Use the initial configuration since we can't be shure that the old 950 * paths are valid. 951 */ 952 io_subchannel_init_config(sch); 953 if (cio_commit_config(sch)) 954 return; 955 956 /* We should also udate ssd info, but this has to wait. */ 957 /* Check if this is another device which appeared on the same sch. */ 958 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) 959 css_schedule_eval(sch->schid); 960 else 961 ccw_device_start_id(cdev, 0); 962 } 963 964 static void ccw_device_disabled_irq(struct ccw_device *cdev, 965 enum dev_event dev_event) 966 { 967 struct subchannel *sch; 968 969 sch = to_subchannel(cdev->dev.parent); 970 /* 971 * An interrupt in a disabled state means a previous disable was not 972 * successful - should not happen, but we try to disable again. 973 */ 974 cio_disable_subchannel(sch); 975 } 976 977 static void 978 ccw_device_change_cmfstate(struct ccw_device *cdev, enum dev_event dev_event) 979 { 980 retry_set_schib(cdev); 981 cdev->private->state = DEV_STATE_ONLINE; 982 dev_fsm_event(cdev, dev_event); 983 } 984 985 static void ccw_device_update_cmfblock(struct ccw_device *cdev, 986 enum dev_event dev_event) 987 { 988 cmf_retry_copy_block(cdev); 989 cdev->private->state = DEV_STATE_ONLINE; 990 dev_fsm_event(cdev, dev_event); 991 } 992 993 static void 994 ccw_device_quiesce_done(struct ccw_device *cdev, enum dev_event dev_event) 995 { 996 ccw_device_set_timeout(cdev, 0); 997 cdev->private->state = DEV_STATE_NOT_OPER; 998 wake_up(&cdev->private->wait_q); 999 } 1000 1001 static void 1002 ccw_device_quiesce_timeout(struct ccw_device *cdev, enum dev_event dev_event) 1003 { 1004 int ret; 1005 1006 ret = ccw_device_cancel_halt_clear(cdev); 1007 if (ret == -EBUSY) { 1008 ccw_device_set_timeout(cdev, HZ/10); 1009 } else { 1010 cdev->private->state = DEV_STATE_NOT_OPER; 1011 wake_up(&cdev->private->wait_q); 1012 } 1013 } 1014 1015 /* 1016 * No operation action. This is used e.g. to ignore a timeout event in 1017 * state offline. 1018 */ 1019 static void 1020 ccw_device_nop(struct ccw_device *cdev, enum dev_event dev_event) 1021 { 1022 } 1023 1024 /* 1025 * device statemachine 1026 */ 1027 fsm_func_t *dev_jumptable[NR_DEV_STATES][NR_DEV_EVENTS] = { 1028 [DEV_STATE_NOT_OPER] = { 1029 [DEV_EVENT_NOTOPER] = ccw_device_nop, 1030 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq, 1031 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1032 [DEV_EVENT_VERIFY] = ccw_device_nop, 1033 }, 1034 [DEV_STATE_SENSE_ID] = { 1035 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1036 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1037 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1038 [DEV_EVENT_VERIFY] = ccw_device_nop, 1039 }, 1040 [DEV_STATE_OFFLINE] = { 1041 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1042 [DEV_EVENT_INTERRUPT] = ccw_device_disabled_irq, 1043 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1044 [DEV_EVENT_VERIFY] = ccw_device_offline_verify, 1045 }, 1046 [DEV_STATE_VERIFY] = { 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_delay_verify, 1051 }, 1052 [DEV_STATE_ONLINE] = { 1053 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1054 [DEV_EVENT_INTERRUPT] = ccw_device_irq, 1055 [DEV_EVENT_TIMEOUT] = ccw_device_online_timeout, 1056 [DEV_EVENT_VERIFY] = ccw_device_online_verify, 1057 }, 1058 [DEV_STATE_W4SENSE] = { 1059 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1060 [DEV_EVENT_INTERRUPT] = ccw_device_w4sense, 1061 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1062 [DEV_EVENT_VERIFY] = ccw_device_online_verify, 1063 }, 1064 [DEV_STATE_DISBAND_PGID] = { 1065 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1066 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1067 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1068 [DEV_EVENT_VERIFY] = ccw_device_nop, 1069 }, 1070 [DEV_STATE_BOXED] = { 1071 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1072 [DEV_EVENT_INTERRUPT] = ccw_device_nop, 1073 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1074 [DEV_EVENT_VERIFY] = ccw_device_boxed_verify, 1075 }, 1076 /* states to wait for i/o completion before doing something */ 1077 [DEV_STATE_TIMEOUT_KILL] = { 1078 [DEV_EVENT_NOTOPER] = ccw_device_generic_notoper, 1079 [DEV_EVENT_INTERRUPT] = ccw_device_killing_irq, 1080 [DEV_EVENT_TIMEOUT] = ccw_device_killing_timeout, 1081 [DEV_EVENT_VERIFY] = ccw_device_nop, //FIXME 1082 }, 1083 [DEV_STATE_QUIESCE] = { 1084 [DEV_EVENT_NOTOPER] = ccw_device_quiesce_done, 1085 [DEV_EVENT_INTERRUPT] = ccw_device_quiesce_done, 1086 [DEV_EVENT_TIMEOUT] = ccw_device_quiesce_timeout, 1087 [DEV_EVENT_VERIFY] = ccw_device_nop, 1088 }, 1089 /* special states for devices gone not operational */ 1090 [DEV_STATE_DISCONNECTED] = { 1091 [DEV_EVENT_NOTOPER] = ccw_device_nop, 1092 [DEV_EVENT_INTERRUPT] = ccw_device_start_id, 1093 [DEV_EVENT_TIMEOUT] = ccw_device_nop, 1094 [DEV_EVENT_VERIFY] = ccw_device_start_id, 1095 }, 1096 [DEV_STATE_DISCONNECTED_SENSE_ID] = { 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 [DEV_STATE_CMFCHANGE] = { 1103 [DEV_EVENT_NOTOPER] = ccw_device_change_cmfstate, 1104 [DEV_EVENT_INTERRUPT] = ccw_device_change_cmfstate, 1105 [DEV_EVENT_TIMEOUT] = ccw_device_change_cmfstate, 1106 [DEV_EVENT_VERIFY] = ccw_device_change_cmfstate, 1107 }, 1108 [DEV_STATE_CMFUPDATE] = { 1109 [DEV_EVENT_NOTOPER] = ccw_device_update_cmfblock, 1110 [DEV_EVENT_INTERRUPT] = ccw_device_update_cmfblock, 1111 [DEV_EVENT_TIMEOUT] = ccw_device_update_cmfblock, 1112 [DEV_EVENT_VERIFY] = ccw_device_update_cmfblock, 1113 }, 1114 [DEV_STATE_STEAL_LOCK] = { 1115 [DEV_EVENT_NOTOPER] = ccw_device_request_event, 1116 [DEV_EVENT_INTERRUPT] = ccw_device_request_event, 1117 [DEV_EVENT_TIMEOUT] = ccw_device_request_event, 1118 [DEV_EVENT_VERIFY] = ccw_device_nop, 1119 }, 1120 }; 1121 1122 EXPORT_SYMBOL_GPL(ccw_device_set_timeout); 1123