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