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 void 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 match_dev_id(struct device *dev, const void *data) 625 { 626 struct ccw_device *cdev = to_ccwdev(dev); 627 struct ccw_dev_id *dev_id = (void *)data; 628 629 return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id); 630 } 631 632 /** 633 * get_ccwdev_by_dev_id() - obtain device from a ccw device id 634 * @dev_id: id of the device to be searched 635 * 636 * This function searches all devices attached to the ccw bus for a device 637 * matching @dev_id. 638 * Returns: 639 * If a device is found its reference count is increased and returned; 640 * else %NULL is returned. 641 */ 642 struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id) 643 { 644 struct device *dev; 645 646 dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id); 647 648 return dev ? to_ccwdev(dev) : NULL; 649 } 650 EXPORT_SYMBOL_GPL(get_ccwdev_by_dev_id); 651 652 static void ccw_device_do_unbind_bind(struct ccw_device *cdev) 653 { 654 int ret; 655 656 if (device_is_registered(&cdev->dev)) { 657 device_release_driver(&cdev->dev); 658 ret = device_attach(&cdev->dev); 659 WARN_ON(ret == -ENODEV); 660 } 661 } 662 663 static void 664 ccw_device_release(struct device *dev) 665 { 666 struct ccw_device *cdev; 667 668 cdev = to_ccwdev(dev); 669 cio_gp_dma_free(cdev->private->dma_pool, cdev->private->dma_area, 670 sizeof(*cdev->private->dma_area)); 671 cio_gp_dma_destroy(cdev->private->dma_pool, &cdev->dev); 672 /* Release reference of parent subchannel. */ 673 put_device(cdev->dev.parent); 674 kfree(cdev->private); 675 kfree(cdev); 676 } 677 678 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch) 679 { 680 struct ccw_device *cdev; 681 struct gen_pool *dma_pool; 682 int ret; 683 684 cdev = kzalloc(sizeof(*cdev), GFP_KERNEL); 685 if (!cdev) { 686 ret = -ENOMEM; 687 goto err_cdev; 688 } 689 cdev->private = kzalloc(sizeof(struct ccw_device_private), 690 GFP_KERNEL | GFP_DMA); 691 if (!cdev->private) { 692 ret = -ENOMEM; 693 goto err_priv; 694 } 695 696 cdev->dev.dma_mask = sch->dev.dma_mask; 697 ret = dma_set_coherent_mask(&cdev->dev, sch->dev.coherent_dma_mask); 698 if (ret) 699 goto err_coherent_mask; 700 701 dma_pool = cio_gp_dma_create(&cdev->dev, 1); 702 if (!dma_pool) { 703 ret = -ENOMEM; 704 goto err_dma_pool; 705 } 706 cdev->private->dma_pool = dma_pool; 707 cdev->private->dma_area = cio_gp_dma_zalloc(dma_pool, &cdev->dev, 708 sizeof(*cdev->private->dma_area)); 709 if (!cdev->private->dma_area) { 710 ret = -ENOMEM; 711 goto err_dma_area; 712 } 713 return cdev; 714 err_dma_area: 715 cio_gp_dma_destroy(dma_pool, &cdev->dev); 716 err_dma_pool: 717 err_coherent_mask: 718 kfree(cdev->private); 719 err_priv: 720 kfree(cdev); 721 err_cdev: 722 return ERR_PTR(ret); 723 } 724 725 static void ccw_device_todo(struct work_struct *work); 726 727 static int io_subchannel_initialize_dev(struct subchannel *sch, 728 struct ccw_device *cdev) 729 { 730 struct ccw_device_private *priv = cdev->private; 731 int ret; 732 733 priv->cdev = cdev; 734 priv->int_class = IRQIO_CIO; 735 priv->state = DEV_STATE_NOT_OPER; 736 priv->dev_id.devno = sch->schib.pmcw.dev; 737 priv->dev_id.ssid = sch->schid.ssid; 738 739 INIT_WORK(&priv->todo_work, ccw_device_todo); 740 INIT_LIST_HEAD(&priv->cmb_list); 741 init_waitqueue_head(&priv->wait_q); 742 timer_setup(&priv->timer, ccw_device_timeout, 0); 743 744 atomic_set(&priv->onoff, 0); 745 cdev->ccwlock = sch->lock; 746 cdev->dev.parent = &sch->dev; 747 cdev->dev.release = ccw_device_release; 748 cdev->dev.bus = &ccw_bus_type; 749 cdev->dev.groups = ccwdev_attr_groups; 750 /* Do first half of device_register. */ 751 device_initialize(&cdev->dev); 752 ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid, 753 cdev->private->dev_id.devno); 754 if (ret) 755 goto out_put; 756 if (!get_device(&sch->dev)) { 757 ret = -ENODEV; 758 goto out_put; 759 } 760 priv->flags.initialized = 1; 761 spin_lock_irq(sch->lock); 762 sch_set_cdev(sch, cdev); 763 spin_unlock_irq(sch->lock); 764 return 0; 765 766 out_put: 767 /* Release reference from device_initialize(). */ 768 put_device(&cdev->dev); 769 return ret; 770 } 771 772 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch) 773 { 774 struct ccw_device *cdev; 775 int ret; 776 777 cdev = io_subchannel_allocate_dev(sch); 778 if (!IS_ERR(cdev)) { 779 ret = io_subchannel_initialize_dev(sch, cdev); 780 if (ret) 781 cdev = ERR_PTR(ret); 782 } 783 return cdev; 784 } 785 786 static void io_subchannel_recog(struct ccw_device *, struct subchannel *); 787 788 static void sch_create_and_recog_new_device(struct subchannel *sch) 789 { 790 struct ccw_device *cdev; 791 792 /* Need to allocate a new ccw device. */ 793 cdev = io_subchannel_create_ccwdev(sch); 794 if (IS_ERR(cdev)) { 795 /* OK, we did everything we could... */ 796 css_sch_device_unregister(sch); 797 return; 798 } 799 /* Start recognition for the new ccw device. */ 800 io_subchannel_recog(cdev, sch); 801 } 802 803 /* 804 * Register recognized device. 805 */ 806 static void io_subchannel_register(struct ccw_device *cdev) 807 { 808 struct subchannel *sch; 809 int ret, adjust_init_count = 1; 810 unsigned long flags; 811 812 sch = to_subchannel(cdev->dev.parent); 813 /* 814 * Check if subchannel is still registered. It may have become 815 * unregistered if a machine check hit us after finishing 816 * device recognition but before the register work could be 817 * queued. 818 */ 819 if (!device_is_registered(&sch->dev)) 820 goto out_err; 821 css_update_ssd_info(sch); 822 /* 823 * io_subchannel_register() will also be called after device 824 * recognition has been done for a boxed device (which will already 825 * be registered). We need to reprobe since we may now have sense id 826 * information. 827 */ 828 if (device_is_registered(&cdev->dev)) { 829 if (!cdev->drv) { 830 ret = device_reprobe(&cdev->dev); 831 if (ret) 832 /* We can't do much here. */ 833 CIO_MSG_EVENT(0, "device_reprobe() returned" 834 " %d for 0.%x.%04x\n", ret, 835 cdev->private->dev_id.ssid, 836 cdev->private->dev_id.devno); 837 } 838 adjust_init_count = 0; 839 goto out; 840 } 841 /* 842 * Now we know this subchannel will stay, we can throw 843 * our delayed uevent. 844 */ 845 if (dev_get_uevent_suppress(&sch->dev)) { 846 dev_set_uevent_suppress(&sch->dev, 0); 847 kobject_uevent(&sch->dev.kobj, KOBJ_ADD); 848 } 849 /* make it known to the system */ 850 ret = device_add(&cdev->dev); 851 if (ret) { 852 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n", 853 cdev->private->dev_id.ssid, 854 cdev->private->dev_id.devno, ret); 855 spin_lock_irqsave(sch->lock, flags); 856 sch_set_cdev(sch, NULL); 857 spin_unlock_irqrestore(sch->lock, flags); 858 /* Release initial device reference. */ 859 put_device(&cdev->dev); 860 goto out_err; 861 } 862 out: 863 cdev->private->flags.recog_done = 1; 864 wake_up(&cdev->private->wait_q); 865 out_err: 866 if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count)) 867 wake_up(&ccw_device_init_wq); 868 } 869 870 /* 871 * subchannel recognition done. Called from the state machine. 872 */ 873 void 874 io_subchannel_recog_done(struct ccw_device *cdev) 875 { 876 if (css_init_done == 0) { 877 cdev->private->flags.recog_done = 1; 878 return; 879 } 880 switch (cdev->private->state) { 881 case DEV_STATE_BOXED: 882 /* Device did not respond in time. */ 883 case DEV_STATE_NOT_OPER: 884 cdev->private->flags.recog_done = 1; 885 /* Remove device found not operational. */ 886 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 887 if (atomic_dec_and_test(&ccw_device_init_count)) 888 wake_up(&ccw_device_init_wq); 889 break; 890 case DEV_STATE_OFFLINE: 891 /* 892 * We can't register the device in interrupt context so 893 * we schedule a work item. 894 */ 895 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER); 896 break; 897 } 898 } 899 900 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch) 901 { 902 /* Increase counter of devices currently in recognition. */ 903 atomic_inc(&ccw_device_init_count); 904 905 /* Start async. device sensing. */ 906 spin_lock_irq(sch->lock); 907 ccw_device_recognition(cdev); 908 spin_unlock_irq(sch->lock); 909 } 910 911 static int ccw_device_move_to_sch(struct ccw_device *cdev, 912 struct subchannel *sch) 913 { 914 struct subchannel *old_sch; 915 int rc, old_enabled = 0; 916 917 old_sch = to_subchannel(cdev->dev.parent); 918 /* Obtain child reference for new parent. */ 919 if (!get_device(&sch->dev)) 920 return -ENODEV; 921 922 if (!sch_is_pseudo_sch(old_sch)) { 923 spin_lock_irq(old_sch->lock); 924 old_enabled = old_sch->schib.pmcw.ena; 925 rc = 0; 926 if (old_enabled) 927 rc = cio_disable_subchannel(old_sch); 928 spin_unlock_irq(old_sch->lock); 929 if (rc == -EBUSY) { 930 /* Release child reference for new parent. */ 931 put_device(&sch->dev); 932 return rc; 933 } 934 } 935 936 mutex_lock(&sch->reg_mutex); 937 rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV); 938 mutex_unlock(&sch->reg_mutex); 939 if (rc) { 940 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n", 941 cdev->private->dev_id.ssid, 942 cdev->private->dev_id.devno, sch->schid.ssid, 943 sch->schib.pmcw.dev, rc); 944 if (old_enabled) { 945 /* Try to reenable the old subchannel. */ 946 spin_lock_irq(old_sch->lock); 947 cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch); 948 spin_unlock_irq(old_sch->lock); 949 } 950 /* Release child reference for new parent. */ 951 put_device(&sch->dev); 952 return rc; 953 } 954 /* Clean up old subchannel. */ 955 if (!sch_is_pseudo_sch(old_sch)) { 956 spin_lock_irq(old_sch->lock); 957 sch_set_cdev(old_sch, NULL); 958 spin_unlock_irq(old_sch->lock); 959 css_schedule_eval(old_sch->schid); 960 } 961 /* Release child reference for old parent. */ 962 put_device(&old_sch->dev); 963 /* Initialize new subchannel. */ 964 spin_lock_irq(sch->lock); 965 cdev->ccwlock = sch->lock; 966 if (!sch_is_pseudo_sch(sch)) 967 sch_set_cdev(sch, cdev); 968 spin_unlock_irq(sch->lock); 969 if (!sch_is_pseudo_sch(sch)) 970 css_update_ssd_info(sch); 971 return 0; 972 } 973 974 static int ccw_device_move_to_orph(struct ccw_device *cdev) 975 { 976 struct subchannel *sch = to_subchannel(cdev->dev.parent); 977 struct channel_subsystem *css = to_css(sch->dev.parent); 978 979 return ccw_device_move_to_sch(cdev, css->pseudo_subchannel); 980 } 981 982 static void io_subchannel_irq(struct subchannel *sch) 983 { 984 struct ccw_device *cdev; 985 986 cdev = sch_get_cdev(sch); 987 988 CIO_TRACE_EVENT(6, "IRQ"); 989 CIO_TRACE_EVENT(6, dev_name(&sch->dev)); 990 if (cdev) 991 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT); 992 else 993 inc_irq_stat(IRQIO_CIO); 994 } 995 996 void io_subchannel_init_config(struct subchannel *sch) 997 { 998 memset(&sch->config, 0, sizeof(sch->config)); 999 sch->config.csense = 1; 1000 } 1001 1002 static void io_subchannel_init_fields(struct subchannel *sch) 1003 { 1004 if (cio_is_console(sch->schid)) 1005 sch->opm = 0xff; 1006 else 1007 sch->opm = chp_get_sch_opm(sch); 1008 sch->lpm = sch->schib.pmcw.pam & sch->opm; 1009 sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC; 1010 1011 CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X" 1012 " - PIM = %02X, PAM = %02X, POM = %02X\n", 1013 sch->schib.pmcw.dev, sch->schid.ssid, 1014 sch->schid.sch_no, sch->schib.pmcw.pim, 1015 sch->schib.pmcw.pam, sch->schib.pmcw.pom); 1016 1017 io_subchannel_init_config(sch); 1018 } 1019 1020 /* 1021 * Note: We always return 0 so that we bind to the device even on error. 1022 * This is needed so that our remove function is called on unregister. 1023 */ 1024 static int io_subchannel_probe(struct subchannel *sch) 1025 { 1026 struct io_subchannel_private *io_priv; 1027 struct ccw_device *cdev; 1028 int rc; 1029 1030 if (cio_is_console(sch->schid)) { 1031 rc = sysfs_create_group(&sch->dev.kobj, 1032 &io_subchannel_attr_group); 1033 if (rc) 1034 CIO_MSG_EVENT(0, "Failed to create io subchannel " 1035 "attributes for subchannel " 1036 "0.%x.%04x (rc=%d)\n", 1037 sch->schid.ssid, sch->schid.sch_no, rc); 1038 /* 1039 * The console subchannel already has an associated ccw_device. 1040 * Throw the delayed uevent for the subchannel, register 1041 * the ccw_device and exit. 1042 */ 1043 if (dev_get_uevent_suppress(&sch->dev)) { 1044 /* should always be the case for the console */ 1045 dev_set_uevent_suppress(&sch->dev, 0); 1046 kobject_uevent(&sch->dev.kobj, KOBJ_ADD); 1047 } 1048 cdev = sch_get_cdev(sch); 1049 rc = device_add(&cdev->dev); 1050 if (rc) { 1051 /* Release online reference. */ 1052 put_device(&cdev->dev); 1053 goto out_schedule; 1054 } 1055 if (atomic_dec_and_test(&ccw_device_init_count)) 1056 wake_up(&ccw_device_init_wq); 1057 return 0; 1058 } 1059 io_subchannel_init_fields(sch); 1060 rc = cio_commit_config(sch); 1061 if (rc) 1062 goto out_schedule; 1063 rc = sysfs_create_group(&sch->dev.kobj, 1064 &io_subchannel_attr_group); 1065 if (rc) 1066 goto out_schedule; 1067 /* Allocate I/O subchannel private data. */ 1068 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA); 1069 if (!io_priv) 1070 goto out_schedule; 1071 1072 io_priv->dma_area = dma_alloc_coherent(&sch->dev, 1073 sizeof(*io_priv->dma_area), 1074 &io_priv->dma_area_dma, GFP_KERNEL); 1075 if (!io_priv->dma_area) { 1076 kfree(io_priv); 1077 goto out_schedule; 1078 } 1079 1080 set_io_private(sch, io_priv); 1081 css_schedule_eval(sch->schid); 1082 return 0; 1083 1084 out_schedule: 1085 spin_lock_irq(sch->lock); 1086 css_sched_sch_todo(sch, SCH_TODO_UNREG); 1087 spin_unlock_irq(sch->lock); 1088 return 0; 1089 } 1090 1091 static void io_subchannel_remove(struct subchannel *sch) 1092 { 1093 struct io_subchannel_private *io_priv = to_io_private(sch); 1094 struct ccw_device *cdev; 1095 1096 cdev = sch_get_cdev(sch); 1097 if (!cdev) 1098 goto out_free; 1099 1100 ccw_device_unregister(cdev); 1101 spin_lock_irq(sch->lock); 1102 sch_set_cdev(sch, NULL); 1103 set_io_private(sch, NULL); 1104 spin_unlock_irq(sch->lock); 1105 out_free: 1106 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area), 1107 io_priv->dma_area, io_priv->dma_area_dma); 1108 kfree(io_priv); 1109 sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group); 1110 } 1111 1112 static void io_subchannel_verify(struct subchannel *sch) 1113 { 1114 struct ccw_device *cdev; 1115 1116 cdev = sch_get_cdev(sch); 1117 if (cdev) 1118 dev_fsm_event(cdev, DEV_EVENT_VERIFY); 1119 } 1120 1121 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask) 1122 { 1123 struct ccw_device *cdev; 1124 1125 cdev = sch_get_cdev(sch); 1126 if (!cdev) 1127 return; 1128 if (cio_update_schib(sch)) 1129 goto err; 1130 /* Check for I/O on path. */ 1131 if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask) 1132 goto out; 1133 if (cdev->private->state == DEV_STATE_ONLINE) { 1134 ccw_device_kill_io(cdev); 1135 goto out; 1136 } 1137 if (cio_clear(sch)) 1138 goto err; 1139 out: 1140 /* Trigger path verification. */ 1141 dev_fsm_event(cdev, DEV_EVENT_VERIFY); 1142 return; 1143 1144 err: 1145 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 1146 } 1147 1148 static int io_subchannel_chp_event(struct subchannel *sch, 1149 struct chp_link *link, int event) 1150 { 1151 struct ccw_device *cdev = sch_get_cdev(sch); 1152 int mask, chpid, valid_bit; 1153 int path_event[8]; 1154 1155 mask = chp_ssd_get_mask(&sch->ssd_info, link); 1156 if (!mask) 1157 return 0; 1158 switch (event) { 1159 case CHP_VARY_OFF: 1160 sch->opm &= ~mask; 1161 sch->lpm &= ~mask; 1162 if (cdev) 1163 cdev->private->path_gone_mask |= mask; 1164 io_subchannel_terminate_path(sch, mask); 1165 break; 1166 case CHP_VARY_ON: 1167 sch->opm |= mask; 1168 sch->lpm |= mask; 1169 if (cdev) 1170 cdev->private->path_new_mask |= mask; 1171 io_subchannel_verify(sch); 1172 break; 1173 case CHP_OFFLINE: 1174 if (cio_update_schib(sch)) 1175 return -ENODEV; 1176 if (cdev) 1177 cdev->private->path_gone_mask |= mask; 1178 io_subchannel_terminate_path(sch, mask); 1179 break; 1180 case CHP_ONLINE: 1181 if (cio_update_schib(sch)) 1182 return -ENODEV; 1183 sch->lpm |= mask & sch->opm; 1184 if (cdev) 1185 cdev->private->path_new_mask |= mask; 1186 io_subchannel_verify(sch); 1187 break; 1188 case CHP_FCES_EVENT: 1189 /* Forward Endpoint Security event */ 1190 for (chpid = 0, valid_bit = 0x80; chpid < 8; chpid++, 1191 valid_bit >>= 1) { 1192 if (mask & valid_bit) 1193 path_event[chpid] = PE_PATH_FCES_EVENT; 1194 else 1195 path_event[chpid] = PE_NONE; 1196 } 1197 if (cdev) 1198 cdev->drv->path_event(cdev, path_event); 1199 break; 1200 } 1201 return 0; 1202 } 1203 1204 static void io_subchannel_quiesce(struct subchannel *sch) 1205 { 1206 struct ccw_device *cdev; 1207 int ret; 1208 1209 spin_lock_irq(sch->lock); 1210 cdev = sch_get_cdev(sch); 1211 if (cio_is_console(sch->schid)) 1212 goto out_unlock; 1213 if (!sch->schib.pmcw.ena) 1214 goto out_unlock; 1215 ret = cio_disable_subchannel(sch); 1216 if (ret != -EBUSY) 1217 goto out_unlock; 1218 if (cdev->handler) 1219 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO)); 1220 while (ret == -EBUSY) { 1221 cdev->private->state = DEV_STATE_QUIESCE; 1222 cdev->private->iretry = 255; 1223 ret = ccw_device_cancel_halt_clear(cdev); 1224 if (ret == -EBUSY) { 1225 ccw_device_set_timeout(cdev, HZ/10); 1226 spin_unlock_irq(sch->lock); 1227 wait_event(cdev->private->wait_q, 1228 cdev->private->state != DEV_STATE_QUIESCE); 1229 spin_lock_irq(sch->lock); 1230 } 1231 ret = cio_disable_subchannel(sch); 1232 } 1233 out_unlock: 1234 spin_unlock_irq(sch->lock); 1235 } 1236 1237 static void io_subchannel_shutdown(struct subchannel *sch) 1238 { 1239 io_subchannel_quiesce(sch); 1240 } 1241 1242 static int device_is_disconnected(struct ccw_device *cdev) 1243 { 1244 if (!cdev) 1245 return 0; 1246 return (cdev->private->state == DEV_STATE_DISCONNECTED || 1247 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID); 1248 } 1249 1250 static int recovery_check(struct device *dev, void *data) 1251 { 1252 struct ccw_device *cdev = to_ccwdev(dev); 1253 struct subchannel *sch; 1254 int *redo = data; 1255 1256 spin_lock_irq(cdev->ccwlock); 1257 switch (cdev->private->state) { 1258 case DEV_STATE_ONLINE: 1259 sch = to_subchannel(cdev->dev.parent); 1260 if ((sch->schib.pmcw.pam & sch->opm) == sch->vpm) 1261 break; 1262 fallthrough; 1263 case DEV_STATE_DISCONNECTED: 1264 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n", 1265 cdev->private->dev_id.ssid, 1266 cdev->private->dev_id.devno); 1267 dev_fsm_event(cdev, DEV_EVENT_VERIFY); 1268 *redo = 1; 1269 break; 1270 case DEV_STATE_DISCONNECTED_SENSE_ID: 1271 *redo = 1; 1272 break; 1273 } 1274 spin_unlock_irq(cdev->ccwlock); 1275 1276 return 0; 1277 } 1278 1279 static void recovery_work_func(struct work_struct *unused) 1280 { 1281 int redo = 0; 1282 1283 bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check); 1284 if (redo) { 1285 spin_lock_irq(&recovery_lock); 1286 if (!timer_pending(&recovery_timer)) { 1287 if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1) 1288 recovery_phase++; 1289 mod_timer(&recovery_timer, jiffies + 1290 recovery_delay[recovery_phase] * HZ); 1291 } 1292 spin_unlock_irq(&recovery_lock); 1293 } else 1294 CIO_MSG_EVENT(3, "recovery: end\n"); 1295 } 1296 1297 static DECLARE_WORK(recovery_work, recovery_work_func); 1298 1299 static void recovery_func(struct timer_list *unused) 1300 { 1301 /* 1302 * We can't do our recovery in softirq context and it's not 1303 * performance critical, so we schedule it. 1304 */ 1305 schedule_work(&recovery_work); 1306 } 1307 1308 void ccw_device_schedule_recovery(void) 1309 { 1310 unsigned long flags; 1311 1312 CIO_MSG_EVENT(3, "recovery: schedule\n"); 1313 spin_lock_irqsave(&recovery_lock, flags); 1314 if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) { 1315 recovery_phase = 0; 1316 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ); 1317 } 1318 spin_unlock_irqrestore(&recovery_lock, flags); 1319 } 1320 1321 static int purge_fn(struct device *dev, void *data) 1322 { 1323 struct ccw_device *cdev = to_ccwdev(dev); 1324 struct ccw_dev_id *id = &cdev->private->dev_id; 1325 1326 spin_lock_irq(cdev->ccwlock); 1327 if (is_blacklisted(id->ssid, id->devno) && 1328 (cdev->private->state == DEV_STATE_OFFLINE) && 1329 (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) { 1330 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid, 1331 id->devno); 1332 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG); 1333 atomic_set(&cdev->private->onoff, 0); 1334 } 1335 spin_unlock_irq(cdev->ccwlock); 1336 /* Abort loop in case of pending signal. */ 1337 if (signal_pending(current)) 1338 return -EINTR; 1339 1340 return 0; 1341 } 1342 1343 /** 1344 * ccw_purge_blacklisted - purge unused, blacklisted devices 1345 * 1346 * Unregister all ccw devices that are offline and on the blacklist. 1347 */ 1348 int ccw_purge_blacklisted(void) 1349 { 1350 CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n"); 1351 bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn); 1352 return 0; 1353 } 1354 1355 void ccw_device_set_disconnected(struct ccw_device *cdev) 1356 { 1357 if (!cdev) 1358 return; 1359 ccw_device_set_timeout(cdev, 0); 1360 cdev->private->flags.fake_irb = 0; 1361 cdev->private->state = DEV_STATE_DISCONNECTED; 1362 if (cdev->online) 1363 ccw_device_schedule_recovery(); 1364 } 1365 1366 void ccw_device_set_notoper(struct ccw_device *cdev) 1367 { 1368 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1369 1370 CIO_TRACE_EVENT(2, "notoper"); 1371 CIO_TRACE_EVENT(2, dev_name(&sch->dev)); 1372 ccw_device_set_timeout(cdev, 0); 1373 cio_disable_subchannel(sch); 1374 cdev->private->state = DEV_STATE_NOT_OPER; 1375 } 1376 1377 enum io_sch_action { 1378 IO_SCH_UNREG, 1379 IO_SCH_ORPH_UNREG, 1380 IO_SCH_ATTACH, 1381 IO_SCH_UNREG_ATTACH, 1382 IO_SCH_ORPH_ATTACH, 1383 IO_SCH_REPROBE, 1384 IO_SCH_VERIFY, 1385 IO_SCH_DISC, 1386 IO_SCH_NOP, 1387 }; 1388 1389 static enum io_sch_action sch_get_action(struct subchannel *sch) 1390 { 1391 struct ccw_device *cdev; 1392 1393 cdev = sch_get_cdev(sch); 1394 if (cio_update_schib(sch)) { 1395 /* Not operational. */ 1396 if (!cdev) 1397 return IO_SCH_UNREG; 1398 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 1399 return IO_SCH_UNREG; 1400 return IO_SCH_ORPH_UNREG; 1401 } 1402 /* Operational. */ 1403 if (!cdev) 1404 return IO_SCH_ATTACH; 1405 if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) { 1406 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK) 1407 return IO_SCH_UNREG_ATTACH; 1408 return IO_SCH_ORPH_ATTACH; 1409 } 1410 if ((sch->schib.pmcw.pam & sch->opm) == 0) { 1411 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK) 1412 return IO_SCH_UNREG; 1413 return IO_SCH_DISC; 1414 } 1415 if (device_is_disconnected(cdev)) 1416 return IO_SCH_REPROBE; 1417 if (cdev->online) 1418 return IO_SCH_VERIFY; 1419 if (cdev->private->state == DEV_STATE_NOT_OPER) 1420 return IO_SCH_UNREG_ATTACH; 1421 return IO_SCH_NOP; 1422 } 1423 1424 /** 1425 * io_subchannel_sch_event - process subchannel event 1426 * @sch: subchannel 1427 * @process: non-zero if function is called in process context 1428 * 1429 * An unspecified event occurred for this subchannel. Adjust data according 1430 * to the current operational state of the subchannel and device. Return 1431 * zero when the event has been handled sufficiently or -EAGAIN when this 1432 * function should be called again in process context. 1433 */ 1434 static int io_subchannel_sch_event(struct subchannel *sch, int process) 1435 { 1436 unsigned long flags; 1437 struct ccw_device *cdev; 1438 struct ccw_dev_id dev_id; 1439 enum io_sch_action action; 1440 int rc = -EAGAIN; 1441 1442 spin_lock_irqsave(sch->lock, flags); 1443 if (!device_is_registered(&sch->dev)) 1444 goto out_unlock; 1445 if (work_pending(&sch->todo_work)) 1446 goto out_unlock; 1447 cdev = sch_get_cdev(sch); 1448 if (cdev && work_pending(&cdev->private->todo_work)) 1449 goto out_unlock; 1450 action = sch_get_action(sch); 1451 CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n", 1452 sch->schid.ssid, sch->schid.sch_no, process, 1453 action); 1454 /* Perform immediate actions while holding the lock. */ 1455 switch (action) { 1456 case IO_SCH_REPROBE: 1457 /* Trigger device recognition. */ 1458 ccw_device_trigger_reprobe(cdev); 1459 rc = 0; 1460 goto out_unlock; 1461 case IO_SCH_VERIFY: 1462 /* Trigger path verification. */ 1463 io_subchannel_verify(sch); 1464 rc = 0; 1465 goto out_unlock; 1466 case IO_SCH_DISC: 1467 ccw_device_set_disconnected(cdev); 1468 rc = 0; 1469 goto out_unlock; 1470 case IO_SCH_ORPH_UNREG: 1471 case IO_SCH_ORPH_ATTACH: 1472 ccw_device_set_disconnected(cdev); 1473 break; 1474 case IO_SCH_UNREG_ATTACH: 1475 case IO_SCH_UNREG: 1476 if (!cdev) 1477 break; 1478 if (cdev->private->state == DEV_STATE_SENSE_ID) { 1479 /* 1480 * Note: delayed work triggered by this event 1481 * and repeated calls to sch_event are synchronized 1482 * by the above check for work_pending(cdev). 1483 */ 1484 dev_fsm_event(cdev, DEV_EVENT_NOTOPER); 1485 } else 1486 ccw_device_set_notoper(cdev); 1487 break; 1488 case IO_SCH_NOP: 1489 rc = 0; 1490 goto out_unlock; 1491 default: 1492 break; 1493 } 1494 spin_unlock_irqrestore(sch->lock, flags); 1495 /* All other actions require process context. */ 1496 if (!process) 1497 goto out; 1498 /* Handle attached ccw device. */ 1499 switch (action) { 1500 case IO_SCH_ORPH_UNREG: 1501 case IO_SCH_ORPH_ATTACH: 1502 /* Move ccw device to orphanage. */ 1503 rc = ccw_device_move_to_orph(cdev); 1504 if (rc) 1505 goto out; 1506 break; 1507 case IO_SCH_UNREG_ATTACH: 1508 spin_lock_irqsave(sch->lock, flags); 1509 sch_set_cdev(sch, NULL); 1510 spin_unlock_irqrestore(sch->lock, flags); 1511 /* Unregister ccw device. */ 1512 ccw_device_unregister(cdev); 1513 break; 1514 default: 1515 break; 1516 } 1517 /* Handle subchannel. */ 1518 switch (action) { 1519 case IO_SCH_ORPH_UNREG: 1520 case IO_SCH_UNREG: 1521 css_sch_device_unregister(sch); 1522 break; 1523 case IO_SCH_ORPH_ATTACH: 1524 case IO_SCH_UNREG_ATTACH: 1525 case IO_SCH_ATTACH: 1526 dev_id.ssid = sch->schid.ssid; 1527 dev_id.devno = sch->schib.pmcw.dev; 1528 cdev = get_ccwdev_by_dev_id(&dev_id); 1529 if (!cdev) { 1530 sch_create_and_recog_new_device(sch); 1531 break; 1532 } 1533 rc = ccw_device_move_to_sch(cdev, sch); 1534 if (rc) { 1535 /* Release reference from get_ccwdev_by_dev_id() */ 1536 put_device(&cdev->dev); 1537 goto out; 1538 } 1539 spin_lock_irqsave(sch->lock, flags); 1540 ccw_device_trigger_reprobe(cdev); 1541 spin_unlock_irqrestore(sch->lock, flags); 1542 /* Release reference from get_ccwdev_by_dev_id() */ 1543 put_device(&cdev->dev); 1544 break; 1545 default: 1546 break; 1547 } 1548 return 0; 1549 1550 out_unlock: 1551 spin_unlock_irqrestore(sch->lock, flags); 1552 out: 1553 return rc; 1554 } 1555 1556 static void ccw_device_set_int_class(struct ccw_device *cdev) 1557 { 1558 struct ccw_driver *cdrv = cdev->drv; 1559 1560 /* Note: we interpret class 0 in this context as an uninitialized 1561 * field since it translates to a non-I/O interrupt class. */ 1562 if (cdrv->int_class != 0) 1563 cdev->private->int_class = cdrv->int_class; 1564 else 1565 cdev->private->int_class = IRQIO_CIO; 1566 } 1567 1568 #ifdef CONFIG_CCW_CONSOLE 1569 int __init ccw_device_enable_console(struct ccw_device *cdev) 1570 { 1571 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1572 int rc; 1573 1574 if (!cdev->drv || !cdev->handler) 1575 return -EINVAL; 1576 1577 io_subchannel_init_fields(sch); 1578 rc = cio_commit_config(sch); 1579 if (rc) 1580 return rc; 1581 sch->driver = &io_subchannel_driver; 1582 io_subchannel_recog(cdev, sch); 1583 /* Now wait for the async. recognition to come to an end. */ 1584 spin_lock_irq(cdev->ccwlock); 1585 while (!dev_fsm_final_state(cdev)) 1586 ccw_device_wait_idle(cdev); 1587 1588 /* Hold on to an extra reference while device is online. */ 1589 get_device(&cdev->dev); 1590 rc = ccw_device_online(cdev); 1591 if (rc) 1592 goto out_unlock; 1593 1594 while (!dev_fsm_final_state(cdev)) 1595 ccw_device_wait_idle(cdev); 1596 1597 if (cdev->private->state == DEV_STATE_ONLINE) 1598 cdev->online = 1; 1599 else 1600 rc = -EIO; 1601 out_unlock: 1602 spin_unlock_irq(cdev->ccwlock); 1603 if (rc) /* Give up online reference since onlining failed. */ 1604 put_device(&cdev->dev); 1605 return rc; 1606 } 1607 1608 struct ccw_device * __init ccw_device_create_console(struct ccw_driver *drv) 1609 { 1610 struct io_subchannel_private *io_priv; 1611 struct ccw_device *cdev; 1612 struct subchannel *sch; 1613 1614 sch = cio_probe_console(); 1615 if (IS_ERR(sch)) 1616 return ERR_CAST(sch); 1617 1618 io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA); 1619 if (!io_priv) 1620 goto err_priv; 1621 io_priv->dma_area = dma_alloc_coherent(&sch->dev, 1622 sizeof(*io_priv->dma_area), 1623 &io_priv->dma_area_dma, GFP_KERNEL); 1624 if (!io_priv->dma_area) 1625 goto err_dma_area; 1626 set_io_private(sch, io_priv); 1627 cdev = io_subchannel_create_ccwdev(sch); 1628 if (IS_ERR(cdev)) { 1629 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area), 1630 io_priv->dma_area, io_priv->dma_area_dma); 1631 set_io_private(sch, NULL); 1632 put_device(&sch->dev); 1633 kfree(io_priv); 1634 return cdev; 1635 } 1636 cdev->drv = drv; 1637 ccw_device_set_int_class(cdev); 1638 return cdev; 1639 1640 err_dma_area: 1641 kfree(io_priv); 1642 err_priv: 1643 put_device(&sch->dev); 1644 return ERR_PTR(-ENOMEM); 1645 } 1646 1647 void __init ccw_device_destroy_console(struct ccw_device *cdev) 1648 { 1649 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1650 struct io_subchannel_private *io_priv = to_io_private(sch); 1651 1652 set_io_private(sch, NULL); 1653 dma_free_coherent(&sch->dev, sizeof(*io_priv->dma_area), 1654 io_priv->dma_area, io_priv->dma_area_dma); 1655 put_device(&sch->dev); 1656 put_device(&cdev->dev); 1657 kfree(io_priv); 1658 } 1659 1660 /** 1661 * ccw_device_wait_idle() - busy wait for device to become idle 1662 * @cdev: ccw device 1663 * 1664 * Poll until activity control is zero, that is, no function or data 1665 * transfer is pending/active. 1666 * Called with device lock being held. 1667 */ 1668 void ccw_device_wait_idle(struct ccw_device *cdev) 1669 { 1670 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1671 1672 while (1) { 1673 cio_tsch(sch); 1674 if (sch->schib.scsw.cmd.actl == 0) 1675 break; 1676 udelay(100); 1677 } 1678 } 1679 #endif 1680 1681 /** 1682 * get_ccwdev_by_busid() - obtain device from a bus id 1683 * @cdrv: driver the device is owned by 1684 * @bus_id: bus id of the device to be searched 1685 * 1686 * This function searches all devices owned by @cdrv for a device with a bus 1687 * id matching @bus_id. 1688 * Returns: 1689 * If a match is found, its reference count of the found device is increased 1690 * and it is returned; else %NULL is returned. 1691 */ 1692 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv, 1693 const char *bus_id) 1694 { 1695 struct device *dev; 1696 1697 dev = driver_find_device_by_name(&cdrv->driver, bus_id); 1698 1699 return dev ? to_ccwdev(dev) : NULL; 1700 } 1701 1702 /************************** device driver handling ************************/ 1703 1704 /* This is the implementation of the ccw_driver class. The probe, remove 1705 * and release methods are initially very similar to the device_driver 1706 * implementations, with the difference that they have ccw_device 1707 * arguments. 1708 * 1709 * A ccw driver also contains the information that is needed for 1710 * device matching. 1711 */ 1712 static int 1713 ccw_device_probe (struct device *dev) 1714 { 1715 struct ccw_device *cdev = to_ccwdev(dev); 1716 struct ccw_driver *cdrv = to_ccwdrv(dev->driver); 1717 int ret; 1718 1719 cdev->drv = cdrv; /* to let the driver call _set_online */ 1720 ccw_device_set_int_class(cdev); 1721 ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV; 1722 if (ret) { 1723 cdev->drv = NULL; 1724 cdev->private->int_class = IRQIO_CIO; 1725 return ret; 1726 } 1727 1728 return 0; 1729 } 1730 1731 static void ccw_device_remove(struct device *dev) 1732 { 1733 struct ccw_device *cdev = to_ccwdev(dev); 1734 struct ccw_driver *cdrv = cdev->drv; 1735 struct subchannel *sch; 1736 int ret; 1737 1738 if (cdrv->remove) 1739 cdrv->remove(cdev); 1740 1741 spin_lock_irq(cdev->ccwlock); 1742 if (cdev->online) { 1743 cdev->online = 0; 1744 ret = ccw_device_offline(cdev); 1745 spin_unlock_irq(cdev->ccwlock); 1746 if (ret == 0) 1747 wait_event(cdev->private->wait_q, 1748 dev_fsm_final_state(cdev)); 1749 else 1750 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, " 1751 "device 0.%x.%04x\n", 1752 ret, cdev->private->dev_id.ssid, 1753 cdev->private->dev_id.devno); 1754 /* Give up reference obtained in ccw_device_set_online(). */ 1755 put_device(&cdev->dev); 1756 spin_lock_irq(cdev->ccwlock); 1757 } 1758 ccw_device_set_timeout(cdev, 0); 1759 cdev->drv = NULL; 1760 cdev->private->int_class = IRQIO_CIO; 1761 sch = to_subchannel(cdev->dev.parent); 1762 spin_unlock_irq(cdev->ccwlock); 1763 io_subchannel_quiesce(sch); 1764 __disable_cmf(cdev); 1765 } 1766 1767 static void ccw_device_shutdown(struct device *dev) 1768 { 1769 struct ccw_device *cdev; 1770 1771 cdev = to_ccwdev(dev); 1772 if (cdev->drv && cdev->drv->shutdown) 1773 cdev->drv->shutdown(cdev); 1774 __disable_cmf(cdev); 1775 } 1776 1777 static struct bus_type ccw_bus_type = { 1778 .name = "ccw", 1779 .match = ccw_bus_match, 1780 .uevent = ccw_uevent, 1781 .probe = ccw_device_probe, 1782 .remove = ccw_device_remove, 1783 .shutdown = ccw_device_shutdown, 1784 }; 1785 1786 /** 1787 * ccw_driver_register() - register a ccw driver 1788 * @cdriver: driver to be registered 1789 * 1790 * This function is mainly a wrapper around driver_register(). 1791 * Returns: 1792 * %0 on success and a negative error value on failure. 1793 */ 1794 int ccw_driver_register(struct ccw_driver *cdriver) 1795 { 1796 struct device_driver *drv = &cdriver->driver; 1797 1798 drv->bus = &ccw_bus_type; 1799 1800 return driver_register(drv); 1801 } 1802 1803 /** 1804 * ccw_driver_unregister() - deregister a ccw driver 1805 * @cdriver: driver to be deregistered 1806 * 1807 * This function is mainly a wrapper around driver_unregister(). 1808 */ 1809 void ccw_driver_unregister(struct ccw_driver *cdriver) 1810 { 1811 driver_unregister(&cdriver->driver); 1812 } 1813 1814 static void ccw_device_todo(struct work_struct *work) 1815 { 1816 struct ccw_device_private *priv; 1817 struct ccw_device *cdev; 1818 struct subchannel *sch; 1819 enum cdev_todo todo; 1820 1821 priv = container_of(work, struct ccw_device_private, todo_work); 1822 cdev = priv->cdev; 1823 sch = to_subchannel(cdev->dev.parent); 1824 /* Find out todo. */ 1825 spin_lock_irq(cdev->ccwlock); 1826 todo = priv->todo; 1827 priv->todo = CDEV_TODO_NOTHING; 1828 CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n", 1829 priv->dev_id.ssid, priv->dev_id.devno, todo); 1830 spin_unlock_irq(cdev->ccwlock); 1831 /* Perform todo. */ 1832 switch (todo) { 1833 case CDEV_TODO_ENABLE_CMF: 1834 cmf_reenable(cdev); 1835 break; 1836 case CDEV_TODO_REBIND: 1837 ccw_device_do_unbind_bind(cdev); 1838 break; 1839 case CDEV_TODO_REGISTER: 1840 io_subchannel_register(cdev); 1841 break; 1842 case CDEV_TODO_UNREG_EVAL: 1843 if (!sch_is_pseudo_sch(sch)) 1844 css_schedule_eval(sch->schid); 1845 fallthrough; 1846 case CDEV_TODO_UNREG: 1847 spin_lock_irq(sch->lock); 1848 sch_set_cdev(sch, NULL); 1849 spin_unlock_irq(sch->lock); 1850 ccw_device_unregister(cdev); 1851 break; 1852 default: 1853 break; 1854 } 1855 /* Release workqueue ref. */ 1856 put_device(&cdev->dev); 1857 } 1858 1859 /** 1860 * ccw_device_sched_todo - schedule ccw device operation 1861 * @cdev: ccw device 1862 * @todo: todo 1863 * 1864 * Schedule the operation identified by @todo to be performed on the slow path 1865 * workqueue. Do nothing if another operation with higher priority is already 1866 * scheduled. Needs to be called with ccwdev lock held. 1867 */ 1868 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo) 1869 { 1870 CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n", 1871 cdev->private->dev_id.ssid, cdev->private->dev_id.devno, 1872 todo); 1873 if (cdev->private->todo >= todo) 1874 return; 1875 cdev->private->todo = todo; 1876 /* Get workqueue ref. */ 1877 if (!get_device(&cdev->dev)) 1878 return; 1879 if (!queue_work(cio_work_q, &cdev->private->todo_work)) { 1880 /* Already queued, release workqueue ref. */ 1881 put_device(&cdev->dev); 1882 } 1883 } 1884 1885 /** 1886 * ccw_device_siosl() - initiate logging 1887 * @cdev: ccw device 1888 * 1889 * This function is used to invoke model-dependent logging within the channel 1890 * subsystem. 1891 */ 1892 int ccw_device_siosl(struct ccw_device *cdev) 1893 { 1894 struct subchannel *sch = to_subchannel(cdev->dev.parent); 1895 1896 return chsc_siosl(sch->schid); 1897 } 1898 EXPORT_SYMBOL_GPL(ccw_device_siosl); 1899 1900 EXPORT_SYMBOL(ccw_device_set_online); 1901 EXPORT_SYMBOL(ccw_device_set_offline); 1902 EXPORT_SYMBOL(ccw_driver_register); 1903 EXPORT_SYMBOL(ccw_driver_unregister); 1904 EXPORT_SYMBOL(get_ccwdev_by_busid); 1905