1 // SPDX-License-Identifier: GPL-1.0+ 2 /* 3 * bus driver for ccw devices 4 * 5 * Copyright IBM Corp. 2002, 2008 6 * Author(s): Arnd Bergmann (arndb@de.ibm.com) 7 * Cornelia Huck (cornelia.huck@de.ibm.com) 8 * Martin Schwidefsky (schwidefsky@de.ibm.com) 9 */ 10 11 #define KMSG_COMPONENT "cio" 12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 13 14 #include <linux/export.h> 15 #include <linux/init.h> 16 #include <linux/spinlock.h> 17 #include <linux/errno.h> 18 #include <linux/err.h> 19 #include <linux/slab.h> 20 #include <linux/list.h> 21 #include <linux/device.h> 22 #include <linux/workqueue.h> 23 #include <linux/delay.h> 24 #include <linux/timer.h> 25 #include <linux/kernel_stat.h> 26 #include <linux/sched/signal.h> 27 #include <linux/dma-mapping.h> 28 29 #include <asm/ccwdev.h> 30 #include <asm/cio.h> 31 #include <asm/param.h> /* HZ */ 32 #include <asm/cmb.h> 33 #include <asm/isc.h> 34 35 #include "chp.h" 36 #include "cio.h" 37 #include "cio_debug.h" 38 #include "css.h" 39 #include "device.h" 40 #include "ioasm.h" 41 #include "io_sch.h" 42 #include "blacklist.h" 43 #include "chsc.h" 44 45 static struct timer_list recovery_timer; 46 static DEFINE_SPINLOCK(recovery_lock); 47 static int recovery_phase; 48 static const unsigned long recovery_delay[] = { 3, 30, 300 }; 49 50 static atomic_t ccw_device_init_count = ATOMIC_INIT(0); 51 static DECLARE_WAIT_QUEUE_HEAD(ccw_device_init_wq); 52 static struct bus_type ccw_bus_type; 53 54 /******************* bus type handling ***********************/ 55 56 /* The Linux driver model distinguishes between a bus type and 57 * the bus itself. Of course we only have one channel 58 * subsystem driver and one channel system per machine, but 59 * we still use the abstraction. T.R. says it's a good idea. */ 60 static int 61 ccw_bus_match (struct device * dev, struct device_driver * drv) 62 { 63 struct ccw_device *cdev = to_ccwdev(dev); 64 struct ccw_driver *cdrv = to_ccwdrv(drv); 65 const struct ccw_device_id *ids = cdrv->ids, *found; 66 67 if (!ids) 68 return 0; 69 70 found = ccw_device_id_match(ids, &cdev->id); 71 if (!found) 72 return 0; 73 74 cdev->id.driver_info = found->driver_info; 75 76 return 1; 77 } 78 79 /* Store modalias string delimited by prefix/suffix string into buffer with 80 * specified size. Return length of resulting string (excluding trailing '\0') 81 * even if string doesn't fit buffer (snprintf semantics). */ 82 static int snprint_alias(char *buf, size_t size, 83 struct ccw_device_id *id, const char *suffix) 84 { 85 int len; 86 87 len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model); 88 if (len > size) 89 return len; 90 buf += len; 91 size -= len; 92 93 if (id->dev_type != 0) 94 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type, 95 id->dev_model, suffix); 96 else 97 len += snprintf(buf, size, "dtdm%s", suffix); 98 99 return len; 100 } 101 102 /* Set up environment variables for ccw device uevent. Return 0 on success, 103 * non-zero otherwise. */ 104 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env) 105 { 106 struct ccw_device *cdev = to_ccwdev(dev); 107 struct ccw_device_id *id = &(cdev->id); 108 int ret; 109 char modalias_buf[30]; 110 111 /* CU_TYPE= */ 112 ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type); 113 if (ret) 114 return ret; 115 116 /* CU_MODEL= */ 117 ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model); 118 if (ret) 119 return ret; 120 121 /* The next two can be zero, that's ok for us */ 122 /* DEV_TYPE= */ 123 ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type); 124 if (ret) 125 return ret; 126 127 /* DEV_MODEL= */ 128 ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model); 129 if (ret) 130 return ret; 131 132 /* MODALIAS= */ 133 snprint_alias(modalias_buf, sizeof(modalias_buf), id, ""); 134 ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf); 135 return ret; 136 } 137 138 static void io_subchannel_irq(struct subchannel *); 139 static int io_subchannel_probe(struct subchannel *); 140 static int io_subchannel_remove(struct subchannel *); 141 static void io_subchannel_shutdown(struct subchannel *); 142 static int io_subchannel_sch_event(struct subchannel *, int); 143 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *, 144 int); 145 static void recovery_func(struct timer_list *unused); 146 147 static struct css_device_id io_subchannel_ids[] = { 148 { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, }, 149 { /* end of list */ }, 150 }; 151 152 static int io_subchannel_settle(void) 153 { 154 int ret; 155 156 ret = wait_event_interruptible(ccw_device_init_wq, 157 atomic_read(&ccw_device_init_count) == 0); 158 if (ret) 159 return -EINTR; 160 flush_workqueue(cio_work_q); 161 return 0; 162 } 163 164 static struct css_driver io_subchannel_driver = { 165 .drv = { 166 .owner = THIS_MODULE, 167 .name = "io_subchannel", 168 }, 169 .subchannel_type = io_subchannel_ids, 170 .irq = io_subchannel_irq, 171 .sch_event = io_subchannel_sch_event, 172 .chp_event = io_subchannel_chp_event, 173 .probe = io_subchannel_probe, 174 .remove = io_subchannel_remove, 175 .shutdown = io_subchannel_shutdown, 176 .settle = io_subchannel_settle, 177 }; 178 179 int __init io_subchannel_init(void) 180 { 181 int ret; 182 183 timer_setup(&recovery_timer, recovery_func, 0); 184 ret = bus_register(&ccw_bus_type); 185 if (ret) 186 return ret; 187 ret = css_driver_register(&io_subchannel_driver); 188 if (ret) 189 bus_unregister(&ccw_bus_type); 190 191 return ret; 192 } 193 194 195 /************************ device handling **************************/ 196 197 static ssize_t 198 devtype_show (struct device *dev, struct device_attribute *attr, char *buf) 199 { 200 struct ccw_device *cdev = to_ccwdev(dev); 201 struct ccw_device_id *id = &(cdev->id); 202 203 if (id->dev_type != 0) 204 return sprintf(buf, "%04x/%02x\n", 205 id->dev_type, id->dev_model); 206 else 207 return sprintf(buf, "n/a\n"); 208 } 209 210 static ssize_t 211 cutype_show (struct device *dev, struct device_attribute *attr, char *buf) 212 { 213 struct ccw_device *cdev = to_ccwdev(dev); 214 struct ccw_device_id *id = &(cdev->id); 215 216 return sprintf(buf, "%04x/%02x\n", 217 id->cu_type, id->cu_model); 218 } 219 220 static ssize_t 221 modalias_show (struct device *dev, struct device_attribute *attr, char *buf) 222 { 223 struct ccw_device *cdev = to_ccwdev(dev); 224 struct ccw_device_id *id = &(cdev->id); 225 int len; 226 227 len = snprint_alias(buf, PAGE_SIZE, id, "\n"); 228 229 return len > PAGE_SIZE ? PAGE_SIZE : len; 230 } 231 232 static ssize_t 233 online_show (struct device *dev, struct device_attribute *attr, char *buf) 234 { 235 struct ccw_device *cdev = to_ccwdev(dev); 236 237 return sprintf(buf, cdev->online ? "1\n" : "0\n"); 238 } 239 240 int ccw_device_is_orphan(struct ccw_device *cdev) 241 { 242 return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent)); 243 } 244 245 static void ccw_device_unregister(struct ccw_device *cdev) 246 { 247 if (device_is_registered(&cdev->dev)) { 248 /* Undo device_add(). */ 249 device_del(&cdev->dev); 250 } 251 if (cdev->private->flags.initialized) { 252 cdev->private->flags.initialized = 0; 253 /* Release reference from device_initialize(). */ 254 put_device(&cdev->dev); 255 } 256 } 257 258 static void io_subchannel_quiesce(struct subchannel *); 259 260 /** 261 * ccw_device_set_offline() - disable a ccw device for I/O 262 * @cdev: target ccw device 263 * 264 * This function calls the driver's set_offline() function for @cdev, if 265 * given, and then disables @cdev. 266 * Returns: 267 * %0 on success and a negative error value on failure. 268 * Context: 269 * enabled, ccw device lock not held 270 */ 271 int ccw_device_set_offline(struct ccw_device *cdev) 272 { 273 struct subchannel *sch; 274 int ret, state; 275 276 if (!cdev) 277 return -ENODEV; 278 if (!cdev->online || !cdev->drv) 279 return -EINVAL; 280 281 if (cdev->drv->set_offline) { 282 ret = cdev->drv->set_offline(cdev); 283 if (ret != 0) 284 return ret; 285 } 286 spin_lock_irq(cdev->ccwlock); 287 sch = to_subchannel(cdev->dev.parent); 288 cdev->online = 0; 289 /* Wait until a final state or DISCONNECTED is reached */ 290 while (!dev_fsm_final_state(cdev) && 291 cdev->private->state != DEV_STATE_DISCONNECTED) { 292 spin_unlock_irq(cdev->ccwlock); 293 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) || 294 cdev->private->state == DEV_STATE_DISCONNECTED)); 295 spin_lock_irq(cdev->ccwlock); 296 } 297 do { 298 ret = ccw_device_offline(cdev); 299 if (!ret) 300 break; 301 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device " 302 "0.%x.%04x\n", ret, cdev->private->dev_id.ssid, 303 cdev->private->dev_id.devno); 304 if (ret != -EBUSY) 305 goto error; 306 state = cdev->private->state; 307 spin_unlock_irq(cdev->ccwlock); 308 io_subchannel_quiesce(sch); 309 spin_lock_irq(cdev->ccwlock); 310 cdev->private->state = state; 311 } while (ret == -EBUSY); 312 spin_unlock_irq(cdev->ccwlock); 313 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) || 314 cdev->private->state == DEV_STATE_DISCONNECTED)); 315 /* Inform the user if set offline failed. */ 316 if (cdev->private->state == DEV_STATE_BOXED) { 317 pr_warn("%s: The device entered boxed state while being set offline\n", 318 dev_name(&cdev->dev)); 319 } else if (cdev->private->state == DEV_STATE_NOT_OPER) { 320 pr_warn("%s: The device stopped operating while being set offline\n", 321 dev_name(&cdev->dev)); 322 } 323 /* Give up reference from ccw_device_set_online(). */ 324 put_device(&cdev->dev); 325 return 0; 326 327 error: 328 cdev->private->state = DEV_STATE_OFFLINE; 329 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 330 spin_unlock_irq(cdev->ccwlock); 331 /* Give up reference from ccw_device_set_online(). */ 332 put_device(&cdev->dev); 333 return -ENODEV; 334 } 335 336 /** 337 * ccw_device_set_online() - enable a ccw device for I/O 338 * @cdev: target ccw device 339 * 340 * This function first enables @cdev and then calls the driver's set_online() 341 * function for @cdev, if given. If set_online() returns an error, @cdev is 342 * disabled again. 343 * Returns: 344 * %0 on success and a negative error value on failure. 345 * Context: 346 * enabled, ccw device lock not held 347 */ 348 int ccw_device_set_online(struct ccw_device *cdev) 349 { 350 int ret; 351 int ret2; 352 353 if (!cdev) 354 return -ENODEV; 355 if (cdev->online || !cdev->drv) 356 return -EINVAL; 357 /* Hold on to an extra reference while device is online. */ 358 if (!get_device(&cdev->dev)) 359 return -ENODEV; 360 361 spin_lock_irq(cdev->ccwlock); 362 ret = ccw_device_online(cdev); 363 spin_unlock_irq(cdev->ccwlock); 364 if (ret == 0) 365 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev)); 366 else { 367 CIO_MSG_EVENT(0, "ccw_device_online returned %d, " 368 "device 0.%x.%04x\n", 369 ret, cdev->private->dev_id.ssid, 370 cdev->private->dev_id.devno); 371 /* Give up online reference since onlining failed. */ 372 put_device(&cdev->dev); 373 return ret; 374 } 375 spin_lock_irq(cdev->ccwlock); 376 /* Check if online processing was successful */ 377 if ((cdev->private->state != DEV_STATE_ONLINE) && 378 (cdev->private->state != DEV_STATE_W4SENSE)) { 379 spin_unlock_irq(cdev->ccwlock); 380 /* Inform the user that set online failed. */ 381 if (cdev->private->state == DEV_STATE_BOXED) { 382 pr_warn("%s: Setting the device online failed because it is boxed\n", 383 dev_name(&cdev->dev)); 384 } else if (cdev->private->state == DEV_STATE_NOT_OPER) { 385 pr_warn("%s: Setting the device online failed because it is not operational\n", 386 dev_name(&cdev->dev)); 387 } 388 /* Give up online reference since onlining failed. */ 389 put_device(&cdev->dev); 390 return -ENODEV; 391 } 392 spin_unlock_irq(cdev->ccwlock); 393 if (cdev->drv->set_online) 394 ret = cdev->drv->set_online(cdev); 395 if (ret) 396 goto rollback; 397 398 spin_lock_irq(cdev->ccwlock); 399 cdev->online = 1; 400 spin_unlock_irq(cdev->ccwlock); 401 return 0; 402 403 rollback: 404 spin_lock_irq(cdev->ccwlock); 405 /* Wait until a final state or DISCONNECTED is reached */ 406 while (!dev_fsm_final_state(cdev) && 407 cdev->private->state != DEV_STATE_DISCONNECTED) { 408 spin_unlock_irq(cdev->ccwlock); 409 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) || 410 cdev->private->state == DEV_STATE_DISCONNECTED)); 411 spin_lock_irq(cdev->ccwlock); 412 } 413 ret2 = ccw_device_offline(cdev); 414 if (ret2) 415 goto error; 416 spin_unlock_irq(cdev->ccwlock); 417 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) || 418 cdev->private->state == DEV_STATE_DISCONNECTED)); 419 /* Give up online reference since onlining failed. */ 420 put_device(&cdev->dev); 421 return ret; 422 423 error: 424 CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, " 425 "device 0.%x.%04x\n", 426 ret2, cdev->private->dev_id.ssid, 427 cdev->private->dev_id.devno); 428 cdev->private->state = DEV_STATE_OFFLINE; 429 spin_unlock_irq(cdev->ccwlock); 430 /* Give up online reference since onlining failed. */ 431 put_device(&cdev->dev); 432 return ret; 433 } 434 435 static int online_store_handle_offline(struct ccw_device *cdev) 436 { 437 if (cdev->private->state == DEV_STATE_DISCONNECTED) { 438 spin_lock_irq(cdev->ccwlock); 439 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL); 440 spin_unlock_irq(cdev->ccwlock); 441 return 0; 442 } 443 if (cdev->drv && cdev->drv->set_offline) 444 return ccw_device_set_offline(cdev); 445 return -EINVAL; 446 } 447 448 static int online_store_recog_and_online(struct ccw_device *cdev) 449 { 450 /* Do device recognition, if needed. */ 451 if (cdev->private->state == DEV_STATE_BOXED) { 452 spin_lock_irq(cdev->ccwlock); 453 ccw_device_recognition(cdev); 454 spin_unlock_irq(cdev->ccwlock); 455 wait_event(cdev->private->wait_q, 456 cdev->private->flags.recog_done); 457 if (cdev->private->state != DEV_STATE_OFFLINE) 458 /* recognition failed */ 459 return -EAGAIN; 460 } 461 if (cdev->drv && cdev->drv->set_online) 462 return ccw_device_set_online(cdev); 463 return -EINVAL; 464 } 465 466 static int online_store_handle_online(struct ccw_device *cdev, int force) 467 { 468 int ret; 469 470 ret = online_store_recog_and_online(cdev); 471 if (ret && !force) 472 return ret; 473 if (force && cdev->private->state == DEV_STATE_BOXED) { 474 ret = ccw_device_stlck(cdev); 475 if (ret) 476 return ret; 477 if (cdev->id.cu_type == 0) 478 cdev->private->state = DEV_STATE_NOT_OPER; 479 ret = online_store_recog_and_online(cdev); 480 if (ret) 481 return ret; 482 } 483 return 0; 484 } 485 486 static ssize_t online_store (struct device *dev, struct device_attribute *attr, 487 const char *buf, size_t count) 488 { 489 struct ccw_device *cdev = to_ccwdev(dev); 490 int force, ret; 491 unsigned long i; 492 493 /* Prevent conflict between multiple on-/offline processing requests. */ 494 if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0) 495 return -EAGAIN; 496 /* Prevent conflict between internal I/Os and on-/offline processing. */ 497 if (!dev_fsm_final_state(cdev) && 498 cdev->private->state != DEV_STATE_DISCONNECTED) { 499 ret = -EAGAIN; 500 goto out; 501 } 502 /* Prevent conflict between pending work and on-/offline processing.*/ 503 if (work_pending(&cdev->private->todo_work)) { 504 ret = -EAGAIN; 505 goto out; 506 } 507 if (!strncmp(buf, "force\n", count)) { 508 force = 1; 509 i = 1; 510 ret = 0; 511 } else { 512 force = 0; 513 ret = kstrtoul(buf, 16, &i); 514 } 515 if (ret) 516 goto out; 517 518 device_lock(dev); 519 switch (i) { 520 case 0: 521 ret = online_store_handle_offline(cdev); 522 break; 523 case 1: 524 ret = online_store_handle_online(cdev, force); 525 break; 526 default: 527 ret = -EINVAL; 528 } 529 device_unlock(dev); 530 531 out: 532 atomic_set(&cdev->private->onoff, 0); 533 return (ret < 0) ? ret : count; 534 } 535 536 static ssize_t 537 available_show (struct device *dev, struct device_attribute *attr, char *buf) 538 { 539 struct ccw_device *cdev = to_ccwdev(dev); 540 struct subchannel *sch; 541 542 if (ccw_device_is_orphan(cdev)) 543 return sprintf(buf, "no device\n"); 544 switch (cdev->private->state) { 545 case DEV_STATE_BOXED: 546 return sprintf(buf, "boxed\n"); 547 case DEV_STATE_DISCONNECTED: 548 case DEV_STATE_DISCONNECTED_SENSE_ID: 549 case DEV_STATE_NOT_OPER: 550 sch = to_subchannel(dev->parent); 551 if (!sch->lpm) 552 return sprintf(buf, "no path\n"); 553 else 554 return sprintf(buf, "no device\n"); 555 default: 556 /* All other states considered fine. */ 557 return sprintf(buf, "good\n"); 558 } 559 } 560 561 static ssize_t 562 initiate_logging(struct device *dev, struct device_attribute *attr, 563 const char *buf, size_t count) 564 { 565 struct subchannel *sch = to_subchannel(dev); 566 int rc; 567 568 rc = chsc_siosl(sch->schid); 569 if (rc < 0) { 570 pr_warn("Logging for subchannel 0.%x.%04x failed with errno=%d\n", 571 sch->schid.ssid, sch->schid.sch_no, rc); 572 return rc; 573 } 574 pr_notice("Logging for subchannel 0.%x.%04x was triggered\n", 575 sch->schid.ssid, sch->schid.sch_no); 576 return count; 577 } 578 579 static ssize_t vpm_show(struct device *dev, struct device_attribute *attr, 580 char *buf) 581 { 582 struct subchannel *sch = to_subchannel(dev); 583 584 return sprintf(buf, "%02x\n", sch->vpm); 585 } 586 587 static DEVICE_ATTR_RO(devtype); 588 static DEVICE_ATTR_RO(cutype); 589 static DEVICE_ATTR_RO(modalias); 590 static DEVICE_ATTR_RW(online); 591 static DEVICE_ATTR(availability, 0444, available_show, NULL); 592 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging); 593 static DEVICE_ATTR_RO(vpm); 594 595 static struct attribute *io_subchannel_attrs[] = { 596 &dev_attr_logging.attr, 597 &dev_attr_vpm.attr, 598 NULL, 599 }; 600 601 static const struct attribute_group io_subchannel_attr_group = { 602 .attrs = io_subchannel_attrs, 603 }; 604 605 static struct attribute * ccwdev_attrs[] = { 606 &dev_attr_devtype.attr, 607 &dev_attr_cutype.attr, 608 &dev_attr_modalias.attr, 609 &dev_attr_online.attr, 610 &dev_attr_cmb_enable.attr, 611 &dev_attr_availability.attr, 612 NULL, 613 }; 614 615 static const struct attribute_group ccwdev_attr_group = { 616 .attrs = ccwdev_attrs, 617 }; 618 619 static const struct attribute_group *ccwdev_attr_groups[] = { 620 &ccwdev_attr_group, 621 NULL, 622 }; 623 624 static int ccw_device_add(struct ccw_device *cdev) 625 { 626 struct device *dev = &cdev->dev; 627 628 dev->bus = &ccw_bus_type; 629 return device_add(dev); 630 } 631 632 static int match_dev_id(struct device *dev, const void *data) 633 { 634 struct ccw_device *cdev = to_ccwdev(dev); 635 struct ccw_dev_id *dev_id = (void *)data; 636 637 return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id); 638 } 639 640 /** 641 * get_ccwdev_by_dev_id() - obtain device from a ccw device id 642 * @dev_id: id of the device to be searched 643 * 644 * This function searches all devices attached to the ccw bus for a device 645 * matching @dev_id. 646 * Returns: 647 * If a device is found its reference count is increased and returned; 648 * else %NULL is returned. 649 */ 650 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id) 651 { 652 struct device *dev; 653 654 dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id); 655 656 return dev ? to_ccwdev(dev) : NULL; 657 } 658 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id); 659 660 static void ccw_device_do_unbind_bind(struct ccw_device *cdev) 661 { 662 int ret; 663 664 if (device_is_registered(&cdev->dev)) { 665 device_release_driver(&cdev->dev); 666 ret = device_attach(&cdev->dev); 667 WARN_ON(ret == -ENODEV); 668 } 669 } 670 671 static void 672 ccw_device_release(struct device *dev) 673 { 674 struct ccw_device *cdev; 675 676 cdev = to_ccwdev(dev); 677 cio_gp_dma_free(cdev->private->dma_pool, cdev->private->dma_area, 678 sizeof(*cdev->private->dma_area)); 679 cio_gp_dma_destroy(cdev->private->dma_pool, &cdev->dev); 680 /* Release reference of parent subchannel. */ 681 put_device(cdev->dev.parent); 682 kfree(cdev->private); 683 kfree(cdev); 684 } 685 686 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch) 687 { 688 struct ccw_device *cdev; 689 struct gen_pool *dma_pool; 690 691 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL); 692 if (!cdev) 693 goto err_cdev; 694 cdev->private = kzalloc(sizeof(struct ccw_device_private), 695 GFP_KERNEL | GFP_DMA); 696 if (!cdev->private) 697 goto err_priv; 698 cdev->dev.coherent_dma_mask = sch->dev.coherent_dma_mask; 699 cdev->dev.dma_mask = sch->dev.dma_mask; 700 dma_pool = cio_gp_dma_create(&cdev->dev, 1); 701 if (!dma_pool) 702 goto err_dma_pool; 703 cdev->private->dma_pool = dma_pool; 704 cdev->private->dma_area = cio_gp_dma_zalloc(dma_pool, &cdev->dev, 705 sizeof(*cdev->private->dma_area)); 706 if (!cdev->private->dma_area) 707 goto err_dma_area; 708 return cdev; 709 err_dma_area: 710 cio_gp_dma_destroy(dma_pool, &cdev->dev); 711 err_dma_pool: 712 kfree(cdev->private); 713 err_priv: 714 kfree(cdev); 715 err_cdev: 716 return ERR_PTR(-ENOMEM); 717 } 718 719 static void ccw_device_todo(struct work_struct *work); 720 721 static int io_subchannel_initialize_dev(struct subchannel *sch, 722 struct ccw_device *cdev) 723 { 724 struct ccw_device_private *priv = cdev->private; 725 int ret; 726 727 priv->cdev = cdev; 728 priv->int_class = IRQIO_CIO; 729 priv->state = DEV_STATE_NOT_OPER; 730 priv->dev_id.devno = sch->schib.pmcw.dev; 731 priv->dev_id.ssid = sch->schid.ssid; 732 733 INIT_WORK(&priv->todo_work, ccw_device_todo); 734 INIT_LIST_HEAD(&priv->cmb_list); 735 init_waitqueue_head(&priv->wait_q); 736 timer_setup(&priv->timer, ccw_device_timeout, 0); 737 738 atomic_set(&priv->onoff, 0); 739 cdev->ccwlock = sch->lock; 740 cdev->dev.parent = &sch->dev; 741 cdev->dev.release = ccw_device_release; 742 cdev->dev.groups = ccwdev_attr_groups; 743 /* Do first half of device_register. */ 744 device_initialize(&cdev->dev); 745 ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid, 746 cdev->private->dev_id.devno); 747 if (ret) 748 goto out_put; 749 if (!get_device(&sch->dev)) { 750 ret = -ENODEV; 751 goto out_put; 752 } 753 priv->flags.initialized = 1; 754 spin_lock_irq(sch->lock); 755 sch_set_cdev(sch, cdev); 756 spin_unlock_irq(sch->lock); 757 return 0; 758 759 out_put: 760 /* Release reference from device_initialize(). */ 761 put_device(&cdev->dev); 762 return ret; 763 } 764 765 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch) 766 { 767 struct ccw_device *cdev; 768 int ret; 769 770 cdev = io_subchannel_allocate_dev(sch); 771 if (!IS_ERR(cdev)) { 772 ret = io_subchannel_initialize_dev(sch, cdev); 773 if (ret) 774 cdev = ERR_PTR(ret); 775 } 776 return cdev; 777 } 778 779 static void io_subchannel_recog(struct ccw_device *, struct subchannel *); 780 781 static void sch_create_and_recog_new_device(struct subchannel *sch) 782 { 783 struct ccw_device *cdev; 784 785 /* Need to allocate a new ccw device. */ 786 cdev = io_subchannel_create_ccwdev(sch); 787 if (IS_ERR(cdev)) { 788 /* OK, we did everything we could... */ 789 css_sch_device_unregister(sch); 790 return; 791 } 792 /* Start recognition for the new ccw device. */ 793 io_subchannel_recog(cdev, sch); 794 } 795 796 /* 797 * Register recognized device. 798 */ 799 static void io_subchannel_register(struct ccw_device *cdev) 800 { 801 struct subchannel *sch; 802 int ret, adjust_init_count = 1; 803 unsigned long flags; 804 805 sch = to_subchannel(cdev->dev.parent); 806 /* 807 * Check if subchannel is still registered. It may have become 808 * unregistered if a machine check hit us after finishing 809 * device recognition but before the register work could be 810 * queued. 811 */ 812 if (!device_is_registered(&sch->dev)) 813 goto out_err; 814 css_update_ssd_info(sch); 815 /* 816 * io_subchannel_register() will also be called after device 817 * recognition has been done for a boxed device (which will already 818 * be registered). We need to reprobe since we may now have sense id 819 * information. 820 */ 821 if (device_is_registered(&cdev->dev)) { 822 if (!cdev->drv) { 823 ret = device_reprobe(&cdev->dev); 824 if (ret) 825 /* We can't do much here. */ 826 CIO_MSG_EVENT(0, "device_reprobe() returned" 827 " %d for 0.%x.%04x\n", ret, 828 cdev->private->dev_id.ssid, 829 cdev->private->dev_id.devno); 830 } 831 adjust_init_count = 0; 832 goto out; 833 } 834 /* 835 * Now we know this subchannel will stay, we can throw 836 * our delayed uevent. 837 */ 838 if (dev_get_uevent_suppress(&sch->dev)) { 839 dev_set_uevent_suppress(&sch->dev, 0); 840 kobject_uevent(&sch->dev.kobj, KOBJ_ADD); 841 } 842 /* make it known to the system */ 843 ret = ccw_device_add(cdev); 844 if (ret) { 845 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n", 846 cdev->private->dev_id.ssid, 847 cdev->private->dev_id.devno, ret); 848 spin_lock_irqsave(sch->lock, flags); 849 sch_set_cdev(sch, NULL); 850 spin_unlock_irqrestore(sch->lock, flags); 851 /* Release initial device reference. */ 852 put_device(&cdev->dev); 853 goto out_err; 854 } 855 out: 856 cdev->private->flags.recog_done = 1; 857 wake_up(&cdev->private->wait_q); 858 out_err: 859 if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count)) 860 wake_up(&ccw_device_init_wq); 861 } 862 863 static void ccw_device_call_sch_unregister(struct ccw_device *cdev) 864 { 865 struct subchannel *sch; 866 867 /* Get subchannel reference for local processing. */ 868 if (!get_device(cdev->dev.parent)) 869 return; 870 sch = to_subchannel(cdev->dev.parent); 871 css_sch_device_unregister(sch); 872 /* Release subchannel reference for local processing. */ 873 put_device(&sch->dev); 874 } 875 876 /* 877 * subchannel recognition done. Called from the state machine. 878 */ 879 void 880 io_subchannel_recog_done(struct ccw_device *cdev) 881 { 882 if (css_init_done == 0) { 883 cdev->private->flags.recog_done = 1; 884 return; 885 } 886 switch (cdev->private->state) { 887 case DEV_STATE_BOXED: 888 /* Device did not respond in time. */ 889 case DEV_STATE_NOT_OPER: 890 cdev->private->flags.recog_done = 1; 891 /* Remove device found not operational. */ 892 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 893 if (atomic_dec_and_test(&ccw_device_init_count)) 894 wake_up(&ccw_device_init_wq); 895 break; 896 case DEV_STATE_OFFLINE: 897 /* 898 * We can't register the device in interrupt context so 899 * we schedule a work item. 900 */ 901 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER); 902 break; 903 } 904 } 905 906 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch) 907 { 908 /* Increase counter of devices currently in recognition. */ 909 atomic_inc(&ccw_device_init_count); 910 911 /* Start async. device sensing. */ 912 spin_lock_irq(sch->lock); 913 ccw_device_recognition(cdev); 914 spin_unlock_irq(sch->lock); 915 } 916 917 static int ccw_device_move_to_sch(struct ccw_device *cdev, 918 struct subchannel *sch) 919 { 920 struct subchannel *old_sch; 921 int rc, old_enabled = 0; 922 923 old_sch = to_subchannel(cdev->dev.parent); 924 /* Obtain child reference for new parent. */ 925 if (!get_device(&sch->dev)) 926 return -ENODEV; 927 928 if (!sch_is_pseudo_sch(old_sch)) { 929 spin_lock_irq(old_sch->lock); 930 old_enabled = old_sch->schib.pmcw.ena; 931 rc = 0; 932 if (old_enabled) 933 rc = cio_disable_subchannel(old_sch); 934 spin_unlock_irq(old_sch->lock); 935 if (rc == -EBUSY) { 936 /* Release child reference for new parent. */ 937 put_device(&sch->dev); 938 return rc; 939 } 940 } 941 942 mutex_lock(&sch->reg_mutex); 943 rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV); 944 mutex_unlock(&sch->reg_mutex); 945 if (rc) { 946 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n", 947 cdev->private->dev_id.ssid, 948 cdev->private->dev_id.devno, sch->schid.ssid, 949 sch->schib.pmcw.dev, rc); 950 if (old_enabled) { 951 /* Try to reenable the old subchannel. */ 952 spin_lock_irq(old_sch->lock); 953 cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch); 954 spin_unlock_irq(old_sch->lock); 955 } 956 /* Release child reference for new parent. */ 957 put_device(&sch->dev); 958 return rc; 959 } 960 /* Clean up old subchannel. */ 961 if (!sch_is_pseudo_sch(old_sch)) { 962 spin_lock_irq(old_sch->lock); 963 sch_set_cdev(old_sch, NULL); 964 spin_unlock_irq(old_sch->lock); 965 css_schedule_eval(old_sch->schid); 966 } 967 /* Release child reference for old parent. */ 968 put_device(&old_sch->dev); 969 /* Initialize new subchannel. */ 970 spin_lock_irq(sch->lock); 971 cdev->ccwlock = sch->lock; 972 if (!sch_is_pseudo_sch(sch)) 973 sch_set_cdev(sch, cdev); 974 spin_unlock_irq(sch->lock); 975 if (!sch_is_pseudo_sch(sch)) 976 css_update_ssd_info(sch); 977 return 0; 978 } 979 980 static int ccw_device_move_to_orph(struct ccw_device *cdev) 981 { 982 struct subchannel *sch = to_subchannel(cdev->dev.parent); 983 struct channel_subsystem *css = to_css(sch->dev.parent); 984 985 return ccw_device_move_to_sch(cdev, css->pseudo_subchannel); 986 } 987 988 static void io_subchannel_irq(struct subchannel *sch) 989 { 990 struct ccw_device *cdev; 991 992 cdev = sch_get_cdev(sch); 993 994 CIO_TRACE_EVENT(6, "IRQ"); 995 CIO_TRACE_EVENT(6, dev_name(&sch->dev)); 996 if (cdev) 997 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT); 998 else 999 inc_irq_stat(IRQIO_CIO); 1000 } 1001 1002 void io_subchannel_init_config(struct subchannel *sch) 1003 { 1004 memset(&sch->config, 0, sizeof(sch->config)); 1005 sch->config.csense = 1; 1006 } 1007 1008 static void io_subchannel_init_fields(struct subchannel *sch) 1009 { 1010 if (cio_is_console(sch->schid)) 1011 sch->opm = 0xff; 1012 else 1013 sch->opm = chp_get_sch_opm(sch); 1014 sch->lpm = sch->schib.pmcw.pam & sch->opm; 1015 sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC; 1016 1017 CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X" 1018 " - PIM = %02X, PAM = %02X, POM = %02X\n", 1019 sch->schib.pmcw.dev, sch->schid.ssid, 1020 sch->schid.sch_no, sch->schib.pmcw.pim, 1021 sch->schib.pmcw.pam, sch->schib.pmcw.pom); 1022 1023 io_subchannel_init_config(sch); 1024 } 1025 1026 /* 1027 * Note: We always return 0 so that we bind to the device even on error. 1028 * This is needed so that our remove function is called on unregister. 1029 */ 1030 static int io_subchannel_probe(struct subchannel *sch) 1031 { 1032 struct io_subchannel_private *io_priv; 1033 struct ccw_device *cdev; 1034 int rc; 1035 1036 if (cio_is_console(sch->schid)) { 1037 rc = sysfs_create_group(&sch->dev.kobj, 1038 &io_subchannel_attr_group); 1039 if (rc) 1040 CIO_MSG_EVENT(0, "Failed to create io subchannel " 1041 "attributes for subchannel " 1042 "0.%x.%04x (rc=%d)\n", 1043 sch->schid.ssid, sch->schid.sch_no, rc); 1044 /* 1045 * The console subchannel already has an associated ccw_device. 1046 * Throw the delayed uevent for the subchannel, register 1047 * the ccw_device and exit. 1048 */ 1049 if (dev_get_uevent_suppress(&sch->dev)) { 1050 /* should always be the case for the console */ 1051 dev_set_uevent_suppress(&sch->dev, 0); 1052 kobject_uevent(&sch->dev.kobj, KOBJ_ADD); 1053 } 1054 cdev = sch_get_cdev(sch); 1055 rc = ccw_device_add(cdev); 1056 if (rc) { 1057 /* Release online reference. */ 1058 put_device(&cdev->dev); 1059 goto out_schedule; 1060 } 1061 if (atomic_dec_and_test(&ccw_device_init_count)) 1062 wake_up(&ccw_device_init_wq); 1063 return 0; 1064 } 1065 io_subchannel_init_fields(sch); 1066 rc = cio_commit_config(sch); 1067 if (rc) 1068 goto out_schedule; 1069 rc = sysfs_create_group(&sch->dev.kobj, 1070 &io_subchannel_attr_group); 1071 if (rc) 1072 goto out_schedule; 1073 /* Allocate I/O subchannel private data. */ 1074 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA); 1075 if (!io_priv) 1076 goto out_schedule; 1077 1078 io_priv->dma_area = dma_alloc_coherent(&sch->dev, 1079 sizeof(*io_priv->dma_area), 1080 &io_priv->dma_area_dma, GFP_KERNEL); 1081 if (!io_priv->dma_area) { 1082 kfree(io_priv); 1083 goto out_schedule; 1084 } 1085 1086 set_io_private(sch, io_priv); 1087 css_schedule_eval(sch->schid); 1088 return 0; 1089 1090 out_schedule: 1091 spin_lock_irq(sch->lock); 1092 css_sched_sch_todo(sch, SCH_TODO_UNREG); 1093 spin_unlock_irq(sch->lock); 1094 return 0; 1095 } 1096 1097 static int io_subchannel_remove(struct subchannel *sch) 1098 { 1099 struct io_subchannel_private *io_priv = to_io_private(sch); 1100 struct ccw_device *cdev; 1101 1102 cdev = sch_get_cdev(sch); 1103 if (!cdev) 1104 goto out_free; 1105 1106 ccw_device_unregister(cdev); 1107 spin_lock_irq(sch->lock); 1108 sch_set_cdev(sch, NULL); 1109 set_io_private(sch, NULL); 1110 spin_unlock_irq(sch->lock); 1111 out_free: 1112 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area), 1113 io_priv->dma_area, io_priv->dma_area_dma); 1114 kfree(io_priv); 1115 sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group); 1116 return 0; 1117 } 1118 1119 static void io_subchannel_verify(struct subchannel *sch) 1120 { 1121 struct ccw_device *cdev; 1122 1123 cdev = sch_get_cdev(sch); 1124 if (cdev) 1125 dev_fsm_event(cdev, DEV_EVENT_VERIFY); 1126 } 1127 1128 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask) 1129 { 1130 struct ccw_device *cdev; 1131 1132 cdev = sch_get_cdev(sch); 1133 if (!cdev) 1134 return; 1135 if (cio_update_schib(sch)) 1136 goto err; 1137 /* Check for I/O on path. */ 1138 if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask) 1139 goto out; 1140 if (cdev->private->state == DEV_STATE_ONLINE) { 1141 ccw_device_kill_io(cdev); 1142 goto out; 1143 } 1144 if (cio_clear(sch)) 1145 goto err; 1146 out: 1147 /* Trigger path verification. */ 1148 dev_fsm_event(cdev, DEV_EVENT_VERIFY); 1149 return; 1150 1151 err: 1152 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 1153 } 1154 1155 static int io_subchannel_chp_event(struct subchannel *sch, 1156 struct chp_link *link, int event) 1157 { 1158 struct ccw_device *cdev = sch_get_cdev(sch); 1159 int mask, chpid, valid_bit; 1160 int path_event[8]; 1161 1162 mask = chp_ssd_get_mask(&sch->ssd_info, link); 1163 if (!mask) 1164 return 0; 1165 switch (event) { 1166 case CHP_VARY_OFF: 1167 sch->opm &= ~mask; 1168 sch->lpm &= ~mask; 1169 if (cdev) 1170 cdev->private->path_gone_mask |= mask; 1171 io_subchannel_terminate_path(sch, mask); 1172 break; 1173 case CHP_VARY_ON: 1174 sch->opm |= mask; 1175 sch->lpm |= mask; 1176 if (cdev) 1177 cdev->private->path_new_mask |= mask; 1178 io_subchannel_verify(sch); 1179 break; 1180 case CHP_OFFLINE: 1181 if (cio_update_schib(sch)) 1182 return -ENODEV; 1183 if (cdev) 1184 cdev->private->path_gone_mask |= mask; 1185 io_subchannel_terminate_path(sch, mask); 1186 break; 1187 case CHP_ONLINE: 1188 if (cio_update_schib(sch)) 1189 return -ENODEV; 1190 sch->lpm |= mask & sch->opm; 1191 if (cdev) 1192 cdev->private->path_new_mask |= mask; 1193 io_subchannel_verify(sch); 1194 break; 1195 case CHP_FCES_EVENT: 1196 /* Forward Endpoint Security event */ 1197 for (chpid = 0, valid_bit = 0x80; chpid < 8; chpid++, 1198 valid_bit >>= 1) { 1199 if (mask & valid_bit) 1200 path_event[chpid] = PE_PATH_FCES_EVENT; 1201 else 1202 path_event[chpid] = PE_NONE; 1203 } 1204 if (cdev) 1205 cdev->drv->path_event(cdev, path_event); 1206 break; 1207 } 1208 return 0; 1209 } 1210 1211 static void io_subchannel_quiesce(struct subchannel *sch) 1212 { 1213 struct ccw_device *cdev; 1214 int ret; 1215 1216 spin_lock_irq(sch->lock); 1217 cdev = sch_get_cdev(sch); 1218 if (cio_is_console(sch->schid)) 1219 goto out_unlock; 1220 if (!sch->schib.pmcw.ena) 1221 goto out_unlock; 1222 ret = cio_disable_subchannel(sch); 1223 if (ret != -EBUSY) 1224 goto out_unlock; 1225 if (cdev->handler) 1226 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO)); 1227 while (ret == -EBUSY) { 1228 cdev->private->state = DEV_STATE_QUIESCE; 1229 cdev->private->iretry = 255; 1230 ret = ccw_device_cancel_halt_clear(cdev); 1231 if (ret == -EBUSY) { 1232 ccw_device_set_timeout(cdev, HZ/10); 1233 spin_unlock_irq(sch->lock); 1234 wait_event(cdev->private->wait_q, 1235 cdev->private->state != DEV_STATE_QUIESCE); 1236 spin_lock_irq(sch->lock); 1237 } 1238 ret = cio_disable_subchannel(sch); 1239 } 1240 out_unlock: 1241 spin_unlock_irq(sch->lock); 1242 } 1243 1244 static void io_subchannel_shutdown(struct subchannel *sch) 1245 { 1246 io_subchannel_quiesce(sch); 1247 } 1248 1249 static int device_is_disconnected(struct ccw_device *cdev) 1250 { 1251 if (!cdev) 1252 return 0; 1253 return (cdev->private->state == DEV_STATE_DISCONNECTED || 1254 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID); 1255 } 1256 1257 static int recovery_check(struct device *dev, void *data) 1258 { 1259 struct ccw_device *cdev = to_ccwdev(dev); 1260 struct subchannel *sch; 1261 int *redo = data; 1262 1263 spin_lock_irq(cdev->ccwlock); 1264 switch (cdev->private->state) { 1265 case DEV_STATE_ONLINE: 1266 sch = to_subchannel(cdev->dev.parent); 1267 if ((sch->schib.pmcw.pam & sch->opm) == sch->vpm) 1268 break; 1269 fallthrough; 1270 case DEV_STATE_DISCONNECTED: 1271 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n", 1272 cdev->private->dev_id.ssid, 1273 cdev->private->dev_id.devno); 1274 dev_fsm_event(cdev, DEV_EVENT_VERIFY); 1275 *redo = 1; 1276 break; 1277 case DEV_STATE_DISCONNECTED_SENSE_ID: 1278 *redo = 1; 1279 break; 1280 } 1281 spin_unlock_irq(cdev->ccwlock); 1282 1283 return 0; 1284 } 1285 1286 static void recovery_work_func(struct work_struct *unused) 1287 { 1288 int redo = 0; 1289 1290 bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check); 1291 if (redo) { 1292 spin_lock_irq(&recovery_lock); 1293 if (!timer_pending(&recovery_timer)) { 1294 if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1) 1295 recovery_phase++; 1296 mod_timer(&recovery_timer, jiffies + 1297 recovery_delay[recovery_phase] * HZ); 1298 } 1299 spin_unlock_irq(&recovery_lock); 1300 } else 1301 CIO_MSG_EVENT(3, "recovery: end\n"); 1302 } 1303 1304 static DECLARE_WORK(recovery_work, recovery_work_func); 1305 1306 static void recovery_func(struct timer_list *unused) 1307 { 1308 /* 1309 * We can't do our recovery in softirq context and it's not 1310 * performance critical, so we schedule it. 1311 */ 1312 schedule_work(&recovery_work); 1313 } 1314 1315 void ccw_device_schedule_recovery(void) 1316 { 1317 unsigned long flags; 1318 1319 CIO_MSG_EVENT(3, "recovery: schedule\n"); 1320 spin_lock_irqsave(&recovery_lock, flags); 1321 if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) { 1322 recovery_phase = 0; 1323 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ); 1324 } 1325 spin_unlock_irqrestore(&recovery_lock, flags); 1326 } 1327 1328 static int purge_fn(struct device *dev, void *data) 1329 { 1330 struct ccw_device *cdev = to_ccwdev(dev); 1331 struct ccw_dev_id *id = &cdev->private->dev_id; 1332 1333 spin_lock_irq(cdev->ccwlock); 1334 if (is_blacklisted(id->ssid, id->devno) && 1335 (cdev->private->state == DEV_STATE_OFFLINE) && 1336 (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) { 1337 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid, 1338 id->devno); 1339 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 1340 atomic_set(&cdev->private->onoff, 0); 1341 } 1342 spin_unlock_irq(cdev->ccwlock); 1343 /* Abort loop in case of pending signal. */ 1344 if (signal_pending(current)) 1345 return -EINTR; 1346 1347 return 0; 1348 } 1349 1350 /** 1351 * ccw_purge_blacklisted - purge unused, blacklisted devices 1352 * 1353 * Unregister all ccw devices that are offline and on the blacklist. 1354 */ 1355 int ccw_purge_blacklisted(void) 1356 { 1357 CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n"); 1358 bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn); 1359 return 0; 1360 } 1361 1362 void ccw_device_set_disconnected(struct ccw_device *cdev) 1363 { 1364 if (!cdev) 1365 return; 1366 ccw_device_set_timeout(cdev, 0); 1367 cdev->private->flags.fake_irb = 0; 1368 cdev->private->state = DEV_STATE_DISCONNECTED; 1369 if (cdev->online) 1370 ccw_device_schedule_recovery(); 1371 } 1372 1373 void ccw_device_set_notoper(struct ccw_device *cdev) 1374 { 1375 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1376 1377 CIO_TRACE_EVENT(2, "notoper"); 1378 CIO_TRACE_EVENT(2, dev_name(&sch->dev)); 1379 ccw_device_set_timeout(cdev, 0); 1380 cio_disable_subchannel(sch); 1381 cdev->private->state = DEV_STATE_NOT_OPER; 1382 } 1383 1384 enum io_sch_action { 1385 IO_SCH_UNREG, 1386 IO_SCH_ORPH_UNREG, 1387 IO_SCH_ATTACH, 1388 IO_SCH_UNREG_ATTACH, 1389 IO_SCH_ORPH_ATTACH, 1390 IO_SCH_REPROBE, 1391 IO_SCH_VERIFY, 1392 IO_SCH_DISC, 1393 IO_SCH_NOP, 1394 }; 1395 1396 static enum io_sch_action sch_get_action(struct subchannel *sch) 1397 { 1398 struct ccw_device *cdev; 1399 1400 cdev = sch_get_cdev(sch); 1401 if (cio_update_schib(sch)) { 1402 /* Not operational. */ 1403 if (!cdev) 1404 return IO_SCH_UNREG; 1405 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 1406 return IO_SCH_UNREG; 1407 return IO_SCH_ORPH_UNREG; 1408 } 1409 /* Operational. */ 1410 if (!cdev) 1411 return IO_SCH_ATTACH; 1412 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) { 1413 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 1414 return IO_SCH_UNREG_ATTACH; 1415 return IO_SCH_ORPH_ATTACH; 1416 } 1417 if ((sch->schib.pmcw.pam & sch->opm) == 0) { 1418 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) 1419 return IO_SCH_UNREG; 1420 return IO_SCH_DISC; 1421 } 1422 if (device_is_disconnected(cdev)) 1423 return IO_SCH_REPROBE; 1424 if (cdev->online) 1425 return IO_SCH_VERIFY; 1426 if (cdev->private->state == DEV_STATE_NOT_OPER) 1427 return IO_SCH_UNREG_ATTACH; 1428 return IO_SCH_NOP; 1429 } 1430 1431 /** 1432 * io_subchannel_sch_event - process subchannel event 1433 * @sch: subchannel 1434 * @process: non-zero if function is called in process context 1435 * 1436 * An unspecified event occurred for this subchannel. Adjust data according 1437 * to the current operational state of the subchannel and device. Return 1438 * zero when the event has been handled sufficiently or -EAGAIN when this 1439 * function should be called again in process context. 1440 */ 1441 static int io_subchannel_sch_event(struct subchannel *sch, int process) 1442 { 1443 unsigned long flags; 1444 struct ccw_device *cdev; 1445 struct ccw_dev_id dev_id; 1446 enum io_sch_action action; 1447 int rc = -EAGAIN; 1448 1449 spin_lock_irqsave(sch->lock, flags); 1450 if (!device_is_registered(&sch->dev)) 1451 goto out_unlock; 1452 if (work_pending(&sch->todo_work)) 1453 goto out_unlock; 1454 cdev = sch_get_cdev(sch); 1455 if (cdev && work_pending(&cdev->private->todo_work)) 1456 goto out_unlock; 1457 action = sch_get_action(sch); 1458 CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n", 1459 sch->schid.ssid, sch->schid.sch_no, process, 1460 action); 1461 /* Perform immediate actions while holding the lock. */ 1462 switch (action) { 1463 case IO_SCH_REPROBE: 1464 /* Trigger device recognition. */ 1465 ccw_device_trigger_reprobe(cdev); 1466 rc = 0; 1467 goto out_unlock; 1468 case IO_SCH_VERIFY: 1469 /* Trigger path verification. */ 1470 io_subchannel_verify(sch); 1471 rc = 0; 1472 goto out_unlock; 1473 case IO_SCH_DISC: 1474 ccw_device_set_disconnected(cdev); 1475 rc = 0; 1476 goto out_unlock; 1477 case IO_SCH_ORPH_UNREG: 1478 case IO_SCH_ORPH_ATTACH: 1479 ccw_device_set_disconnected(cdev); 1480 break; 1481 case IO_SCH_UNREG_ATTACH: 1482 case IO_SCH_UNREG: 1483 if (!cdev) 1484 break; 1485 if (cdev->private->state == DEV_STATE_SENSE_ID) { 1486 /* 1487 * Note: delayed work triggered by this event 1488 * and repeated calls to sch_event are synchronized 1489 * by the above check for work_pending(cdev). 1490 */ 1491 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 1492 } else 1493 ccw_device_set_notoper(cdev); 1494 break; 1495 case IO_SCH_NOP: 1496 rc = 0; 1497 goto out_unlock; 1498 default: 1499 break; 1500 } 1501 spin_unlock_irqrestore(sch->lock, flags); 1502 /* All other actions require process context. */ 1503 if (!process) 1504 goto out; 1505 /* Handle attached ccw device. */ 1506 switch (action) { 1507 case IO_SCH_ORPH_UNREG: 1508 case IO_SCH_ORPH_ATTACH: 1509 /* Move ccw device to orphanage. */ 1510 rc = ccw_device_move_to_orph(cdev); 1511 if (rc) 1512 goto out; 1513 break; 1514 case IO_SCH_UNREG_ATTACH: 1515 spin_lock_irqsave(sch->lock, flags); 1516 sch_set_cdev(sch, NULL); 1517 spin_unlock_irqrestore(sch->lock, flags); 1518 /* Unregister ccw device. */ 1519 ccw_device_unregister(cdev); 1520 break; 1521 default: 1522 break; 1523 } 1524 /* Handle subchannel. */ 1525 switch (action) { 1526 case IO_SCH_ORPH_UNREG: 1527 case IO_SCH_UNREG: 1528 if (!cdev) 1529 css_sch_device_unregister(sch); 1530 break; 1531 case IO_SCH_ORPH_ATTACH: 1532 case IO_SCH_UNREG_ATTACH: 1533 case IO_SCH_ATTACH: 1534 dev_id.ssid = sch->schid.ssid; 1535 dev_id.devno = sch->schib.pmcw.dev; 1536 cdev = get_ccwdev_by_dev_id(&dev_id); 1537 if (!cdev) { 1538 sch_create_and_recog_new_device(sch); 1539 break; 1540 } 1541 rc = ccw_device_move_to_sch(cdev, sch); 1542 if (rc) { 1543 /* Release reference from get_ccwdev_by_dev_id() */ 1544 put_device(&cdev->dev); 1545 goto out; 1546 } 1547 spin_lock_irqsave(sch->lock, flags); 1548 ccw_device_trigger_reprobe(cdev); 1549 spin_unlock_irqrestore(sch->lock, flags); 1550 /* Release reference from get_ccwdev_by_dev_id() */ 1551 put_device(&cdev->dev); 1552 break; 1553 default: 1554 break; 1555 } 1556 return 0; 1557 1558 out_unlock: 1559 spin_unlock_irqrestore(sch->lock, flags); 1560 out: 1561 return rc; 1562 } 1563 1564 static void ccw_device_set_int_class(struct ccw_device *cdev) 1565 { 1566 struct ccw_driver *cdrv = cdev->drv; 1567 1568 /* Note: we interpret class 0 in this context as an uninitialized 1569 * field since it translates to a non-I/O interrupt class. */ 1570 if (cdrv->int_class != 0) 1571 cdev->private->int_class = cdrv->int_class; 1572 else 1573 cdev->private->int_class = IRQIO_CIO; 1574 } 1575 1576 #ifdef CONFIG_CCW_CONSOLE 1577 int __init ccw_device_enable_console(struct ccw_device *cdev) 1578 { 1579 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1580 int rc; 1581 1582 if (!cdev->drv || !cdev->handler) 1583 return -EINVAL; 1584 1585 io_subchannel_init_fields(sch); 1586 rc = cio_commit_config(sch); 1587 if (rc) 1588 return rc; 1589 sch->driver = &io_subchannel_driver; 1590 io_subchannel_recog(cdev, sch); 1591 /* Now wait for the async. recognition to come to an end. */ 1592 spin_lock_irq(cdev->ccwlock); 1593 while (!dev_fsm_final_state(cdev)) 1594 ccw_device_wait_idle(cdev); 1595 1596 /* Hold on to an extra reference while device is online. */ 1597 get_device(&cdev->dev); 1598 rc = ccw_device_online(cdev); 1599 if (rc) 1600 goto out_unlock; 1601 1602 while (!dev_fsm_final_state(cdev)) 1603 ccw_device_wait_idle(cdev); 1604 1605 if (cdev->private->state == DEV_STATE_ONLINE) 1606 cdev->online = 1; 1607 else 1608 rc = -EIO; 1609 out_unlock: 1610 spin_unlock_irq(cdev->ccwlock); 1611 if (rc) /* Give up online reference since onlining failed. */ 1612 put_device(&cdev->dev); 1613 return rc; 1614 } 1615 1616 struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv) 1617 { 1618 struct io_subchannel_private *io_priv; 1619 struct ccw_device *cdev; 1620 struct subchannel *sch; 1621 1622 sch = cio_probe_console(); 1623 if (IS_ERR(sch)) 1624 return ERR_CAST(sch); 1625 1626 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA); 1627 if (!io_priv) 1628 goto err_priv; 1629 io_priv->dma_area = dma_alloc_coherent(&sch->dev, 1630 sizeof(*io_priv->dma_area), 1631 &io_priv->dma_area_dma, GFP_KERNEL); 1632 if (!io_priv->dma_area) 1633 goto err_dma_area; 1634 set_io_private(sch, io_priv); 1635 cdev = io_subchannel_create_ccwdev(sch); 1636 if (IS_ERR(cdev)) { 1637 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area), 1638 io_priv->dma_area, io_priv->dma_area_dma); 1639 set_io_private(sch, NULL); 1640 put_device(&sch->dev); 1641 kfree(io_priv); 1642 return cdev; 1643 } 1644 cdev->drv = drv; 1645 ccw_device_set_int_class(cdev); 1646 return cdev; 1647 1648 err_dma_area: 1649 kfree(io_priv); 1650 err_priv: 1651 put_device(&sch->dev); 1652 return ERR_PTR(-ENOMEM); 1653 } 1654 1655 void __init ccw_device_destroy_console(struct ccw_device *cdev) 1656 { 1657 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1658 struct io_subchannel_private *io_priv = to_io_private(sch); 1659 1660 set_io_private(sch, NULL); 1661 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area), 1662 io_priv->dma_area, io_priv->dma_area_dma); 1663 put_device(&sch->dev); 1664 put_device(&cdev->dev); 1665 kfree(io_priv); 1666 } 1667 1668 /** 1669 * ccw_device_wait_idle() - busy wait for device to become idle 1670 * @cdev: ccw device 1671 * 1672 * Poll until activity control is zero, that is, no function or data 1673 * transfer is pending/active. 1674 * Called with device lock being held. 1675 */ 1676 void ccw_device_wait_idle(struct ccw_device *cdev) 1677 { 1678 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1679 1680 while (1) { 1681 cio_tsch(sch); 1682 if (sch->schib.scsw.cmd.actl == 0) 1683 break; 1684 udelay(100); 1685 } 1686 } 1687 #endif 1688 1689 /** 1690 * get_ccwdev_by_busid() - obtain device from a bus id 1691 * @cdrv: driver the device is owned by 1692 * @bus_id: bus id of the device to be searched 1693 * 1694 * This function searches all devices owned by @cdrv for a device with a bus 1695 * id matching @bus_id. 1696 * Returns: 1697 * If a match is found, its reference count of the found device is increased 1698 * and it is returned; else %NULL is returned. 1699 */ 1700 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv, 1701 const char *bus_id) 1702 { 1703 struct device *dev; 1704 1705 dev = driver_find_device_by_name(&cdrv->driver, bus_id); 1706 1707 return dev ? to_ccwdev(dev) : NULL; 1708 } 1709 1710 /************************** device driver handling ************************/ 1711 1712 /* This is the implementation of the ccw_driver class. The probe, remove 1713 * and release methods are initially very similar to the device_driver 1714 * implementations, with the difference that they have ccw_device 1715 * arguments. 1716 * 1717 * A ccw driver also contains the information that is needed for 1718 * device matching. 1719 */ 1720 static int 1721 ccw_device_probe (struct device *dev) 1722 { 1723 struct ccw_device *cdev = to_ccwdev(dev); 1724 struct ccw_driver *cdrv = to_ccwdrv(dev->driver); 1725 int ret; 1726 1727 cdev->drv = cdrv; /* to let the driver call _set_online */ 1728 ccw_device_set_int_class(cdev); 1729 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV; 1730 if (ret) { 1731 cdev->drv = NULL; 1732 cdev->private->int_class = IRQIO_CIO; 1733 return ret; 1734 } 1735 1736 return 0; 1737 } 1738 1739 static int ccw_device_remove(struct device *dev) 1740 { 1741 struct ccw_device *cdev = to_ccwdev(dev); 1742 struct ccw_driver *cdrv = cdev->drv; 1743 struct subchannel *sch; 1744 int ret; 1745 1746 if (cdrv->remove) 1747 cdrv->remove(cdev); 1748 1749 spin_lock_irq(cdev->ccwlock); 1750 if (cdev->online) { 1751 cdev->online = 0; 1752 ret = ccw_device_offline(cdev); 1753 spin_unlock_irq(cdev->ccwlock); 1754 if (ret == 0) 1755 wait_event(cdev->private->wait_q, 1756 dev_fsm_final_state(cdev)); 1757 else 1758 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, " 1759 "device 0.%x.%04x\n", 1760 ret, cdev->private->dev_id.ssid, 1761 cdev->private->dev_id.devno); 1762 /* Give up reference obtained in ccw_device_set_online(). */ 1763 put_device(&cdev->dev); 1764 spin_lock_irq(cdev->ccwlock); 1765 } 1766 ccw_device_set_timeout(cdev, 0); 1767 cdev->drv = NULL; 1768 cdev->private->int_class = IRQIO_CIO; 1769 sch = to_subchannel(cdev->dev.parent); 1770 spin_unlock_irq(cdev->ccwlock); 1771 io_subchannel_quiesce(sch); 1772 __disable_cmf(cdev); 1773 1774 return 0; 1775 } 1776 1777 static void ccw_device_shutdown(struct device *dev) 1778 { 1779 struct ccw_device *cdev; 1780 1781 cdev = to_ccwdev(dev); 1782 if (cdev->drv && cdev->drv->shutdown) 1783 cdev->drv->shutdown(cdev); 1784 __disable_cmf(cdev); 1785 } 1786 1787 static struct bus_type ccw_bus_type = { 1788 .name = "ccw", 1789 .match = ccw_bus_match, 1790 .uevent = ccw_uevent, 1791 .probe = ccw_device_probe, 1792 .remove = ccw_device_remove, 1793 .shutdown = ccw_device_shutdown, 1794 }; 1795 1796 /** 1797 * ccw_driver_register() - register a ccw driver 1798 * @cdriver: driver to be registered 1799 * 1800 * This function is mainly a wrapper around driver_register(). 1801 * Returns: 1802 * %0 on success and a negative error value on failure. 1803 */ 1804 int ccw_driver_register(struct ccw_driver *cdriver) 1805 { 1806 struct device_driver *drv = &cdriver->driver; 1807 1808 drv->bus = &ccw_bus_type; 1809 1810 return driver_register(drv); 1811 } 1812 1813 /** 1814 * ccw_driver_unregister() - deregister a ccw driver 1815 * @cdriver: driver to be deregistered 1816 * 1817 * This function is mainly a wrapper around driver_unregister(). 1818 */ 1819 void ccw_driver_unregister(struct ccw_driver *cdriver) 1820 { 1821 driver_unregister(&cdriver->driver); 1822 } 1823 1824 static void ccw_device_todo(struct work_struct *work) 1825 { 1826 struct ccw_device_private *priv; 1827 struct ccw_device *cdev; 1828 struct subchannel *sch; 1829 enum cdev_todo todo; 1830 1831 priv = container_of(work, struct ccw_device_private, todo_work); 1832 cdev = priv->cdev; 1833 sch = to_subchannel(cdev->dev.parent); 1834 /* Find out todo. */ 1835 spin_lock_irq(cdev->ccwlock); 1836 todo = priv->todo; 1837 priv->todo = CDEV_TODO_NOTHING; 1838 CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n", 1839 priv->dev_id.ssid, priv->dev_id.devno, todo); 1840 spin_unlock_irq(cdev->ccwlock); 1841 /* Perform todo. */ 1842 switch (todo) { 1843 case CDEV_TODO_ENABLE_CMF: 1844 cmf_reenable(cdev); 1845 break; 1846 case CDEV_TODO_REBIND: 1847 ccw_device_do_unbind_bind(cdev); 1848 break; 1849 case CDEV_TODO_REGISTER: 1850 io_subchannel_register(cdev); 1851 break; 1852 case CDEV_TODO_UNREG_EVAL: 1853 if (!sch_is_pseudo_sch(sch)) 1854 css_schedule_eval(sch->schid); 1855 fallthrough; 1856 case CDEV_TODO_UNREG: 1857 if (sch_is_pseudo_sch(sch)) 1858 ccw_device_unregister(cdev); 1859 else 1860 ccw_device_call_sch_unregister(cdev); 1861 break; 1862 default: 1863 break; 1864 } 1865 /* Release workqueue ref. */ 1866 put_device(&cdev->dev); 1867 } 1868 1869 /** 1870 * ccw_device_sched_todo - schedule ccw device operation 1871 * @cdev: ccw device 1872 * @todo: todo 1873 * 1874 * Schedule the operation identified by @todo to be performed on the slow path 1875 * workqueue. Do nothing if another operation with higher priority is already 1876 * scheduled. Needs to be called with ccwdev lock held. 1877 */ 1878 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo) 1879 { 1880 CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n", 1881 cdev->private->dev_id.ssid, cdev->private->dev_id.devno, 1882 todo); 1883 if (cdev->private->todo >= todo) 1884 return; 1885 cdev->private->todo = todo; 1886 /* Get workqueue ref. */ 1887 if (!get_device(&cdev->dev)) 1888 return; 1889 if (!queue_work(cio_work_q, &cdev->private->todo_work)) { 1890 /* Already queued, release workqueue ref. */ 1891 put_device(&cdev->dev); 1892 } 1893 } 1894 1895 /** 1896 * ccw_device_siosl() - initiate logging 1897 * @cdev: ccw device 1898 * 1899 * This function is used to invoke model-dependent logging within the channel 1900 * subsystem. 1901 */ 1902 int ccw_device_siosl(struct ccw_device *cdev) 1903 { 1904 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1905 1906 return chsc_siosl(sch->schid); 1907 } 1908 EXPORT_SYMBOL_GPL(ccw_device_siosl); 1909 1910 EXPORT_SYMBOL(ccw_device_set_online); 1911 EXPORT_SYMBOL(ccw_device_set_offline); 1912 EXPORT_SYMBOL(ccw_driver_register); 1913 EXPORT_SYMBOL(ccw_driver_unregister); 1914 EXPORT_SYMBOL(get_ccwdev_by_busid); 1915