1 /* 2 * Copyright IBM Corp. 1999, 2010 3 * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com) 4 * Arnd Bergmann (arndb@de.ibm.com) 5 * Peter Oberparleiter <peter.oberparleiter@de.ibm.com> 6 */ 7 8 #include <linux/bug.h> 9 #include <linux/workqueue.h> 10 #include <linux/spinlock.h> 11 #include <linux/export.h> 12 #include <linux/sched.h> 13 #include <linux/init.h> 14 #include <linux/jiffies.h> 15 #include <linux/wait.h> 16 #include <linux/mutex.h> 17 #include <linux/errno.h> 18 #include <linux/slab.h> 19 #include <asm/chpid.h> 20 #include <asm/sclp.h> 21 #include <asm/crw.h> 22 23 #include "cio.h" 24 #include "css.h" 25 #include "ioasm.h" 26 #include "cio_debug.h" 27 #include "chp.h" 28 29 #define to_channelpath(device) container_of(device, struct channel_path, dev) 30 #define CHP_INFO_UPDATE_INTERVAL 1*HZ 31 32 enum cfg_task_t { 33 cfg_none, 34 cfg_configure, 35 cfg_deconfigure 36 }; 37 38 /* Map for pending configure tasks. */ 39 static enum cfg_task_t chp_cfg_task[__MAX_CSSID + 1][__MAX_CHPID + 1]; 40 static DEFINE_MUTEX(cfg_lock); 41 static int cfg_busy; 42 43 /* Map for channel-path status. */ 44 static struct sclp_chp_info chp_info; 45 static DEFINE_MUTEX(info_lock); 46 47 /* Time after which channel-path status may be outdated. */ 48 static unsigned long chp_info_expires; 49 50 /* Workqueue to perform pending configure tasks. */ 51 static struct workqueue_struct *chp_wq; 52 static struct work_struct cfg_work; 53 54 /* Wait queue for configure completion events. */ 55 static wait_queue_head_t cfg_wait_queue; 56 57 /* Set vary state for given chpid. */ 58 static void set_chp_logically_online(struct chp_id chpid, int onoff) 59 { 60 chpid_to_chp(chpid)->state = onoff; 61 } 62 63 /* On success return 0 if channel-path is varied offline, 1 if it is varied 64 * online. Return -ENODEV if channel-path is not registered. */ 65 int chp_get_status(struct chp_id chpid) 66 { 67 return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV); 68 } 69 70 /** 71 * chp_get_sch_opm - return opm for subchannel 72 * @sch: subchannel 73 * 74 * Calculate and return the operational path mask (opm) based on the chpids 75 * used by the subchannel and the status of the associated channel-paths. 76 */ 77 u8 chp_get_sch_opm(struct subchannel *sch) 78 { 79 struct chp_id chpid; 80 int opm; 81 int i; 82 83 opm = 0; 84 chp_id_init(&chpid); 85 for (i = 0; i < 8; i++) { 86 opm <<= 1; 87 chpid.id = sch->schib.pmcw.chpid[i]; 88 if (chp_get_status(chpid) != 0) 89 opm |= 1; 90 } 91 return opm; 92 } 93 EXPORT_SYMBOL_GPL(chp_get_sch_opm); 94 95 /** 96 * chp_is_registered - check if a channel-path is registered 97 * @chpid: channel-path ID 98 * 99 * Return non-zero if a channel-path with the given chpid is registered, 100 * zero otherwise. 101 */ 102 int chp_is_registered(struct chp_id chpid) 103 { 104 return chpid_to_chp(chpid) != NULL; 105 } 106 107 /* 108 * Function: s390_vary_chpid 109 * Varies the specified chpid online or offline 110 */ 111 static int s390_vary_chpid(struct chp_id chpid, int on) 112 { 113 char dbf_text[15]; 114 int status; 115 116 sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid, 117 chpid.id); 118 CIO_TRACE_EVENT(2, dbf_text); 119 120 status = chp_get_status(chpid); 121 if (!on && !status) 122 return 0; 123 124 set_chp_logically_online(chpid, on); 125 chsc_chp_vary(chpid, on); 126 return 0; 127 } 128 129 /* 130 * Channel measurement related functions 131 */ 132 static ssize_t chp_measurement_chars_read(struct file *filp, 133 struct kobject *kobj, 134 struct bin_attribute *bin_attr, 135 char *buf, loff_t off, size_t count) 136 { 137 struct channel_path *chp; 138 struct device *device; 139 140 device = container_of(kobj, struct device, kobj); 141 chp = to_channelpath(device); 142 if (chp->cmg == -1) 143 return 0; 144 145 return memory_read_from_buffer(buf, count, &off, &chp->cmg_chars, 146 sizeof(chp->cmg_chars)); 147 } 148 149 static struct bin_attribute chp_measurement_chars_attr = { 150 .attr = { 151 .name = "measurement_chars", 152 .mode = S_IRUSR, 153 }, 154 .size = sizeof(struct cmg_chars), 155 .read = chp_measurement_chars_read, 156 }; 157 158 static void chp_measurement_copy_block(struct cmg_entry *buf, 159 struct channel_subsystem *css, 160 struct chp_id chpid) 161 { 162 void *area; 163 struct cmg_entry *entry, reference_buf; 164 int idx; 165 166 if (chpid.id < 128) { 167 area = css->cub_addr1; 168 idx = chpid.id; 169 } else { 170 area = css->cub_addr2; 171 idx = chpid.id - 128; 172 } 173 entry = area + (idx * sizeof(struct cmg_entry)); 174 do { 175 memcpy(buf, entry, sizeof(*entry)); 176 memcpy(&reference_buf, entry, sizeof(*entry)); 177 } while (reference_buf.values[0] != buf->values[0]); 178 } 179 180 static ssize_t chp_measurement_read(struct file *filp, struct kobject *kobj, 181 struct bin_attribute *bin_attr, 182 char *buf, loff_t off, size_t count) 183 { 184 struct channel_path *chp; 185 struct channel_subsystem *css; 186 struct device *device; 187 unsigned int size; 188 189 device = container_of(kobj, struct device, kobj); 190 chp = to_channelpath(device); 191 css = to_css(chp->dev.parent); 192 193 size = sizeof(struct cmg_entry); 194 195 /* Only allow single reads. */ 196 if (off || count < size) 197 return 0; 198 chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid); 199 count = size; 200 return count; 201 } 202 203 static struct bin_attribute chp_measurement_attr = { 204 .attr = { 205 .name = "measurement", 206 .mode = S_IRUSR, 207 }, 208 .size = sizeof(struct cmg_entry), 209 .read = chp_measurement_read, 210 }; 211 212 void chp_remove_cmg_attr(struct channel_path *chp) 213 { 214 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr); 215 device_remove_bin_file(&chp->dev, &chp_measurement_attr); 216 } 217 218 int chp_add_cmg_attr(struct channel_path *chp) 219 { 220 int ret; 221 222 ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr); 223 if (ret) 224 return ret; 225 ret = device_create_bin_file(&chp->dev, &chp_measurement_attr); 226 if (ret) 227 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr); 228 return ret; 229 } 230 231 /* 232 * Files for the channel path entries. 233 */ 234 static ssize_t chp_status_show(struct device *dev, 235 struct device_attribute *attr, char *buf) 236 { 237 struct channel_path *chp = to_channelpath(dev); 238 int status; 239 240 mutex_lock(&chp->lock); 241 status = chp->state; 242 mutex_unlock(&chp->lock); 243 244 return status ? sprintf(buf, "online\n") : sprintf(buf, "offline\n"); 245 } 246 247 static ssize_t chp_status_write(struct device *dev, 248 struct device_attribute *attr, 249 const char *buf, size_t count) 250 { 251 struct channel_path *cp = to_channelpath(dev); 252 char cmd[10]; 253 int num_args; 254 int error; 255 256 num_args = sscanf(buf, "%5s", cmd); 257 if (!num_args) 258 return count; 259 260 if (!strncasecmp(cmd, "on", 2) || !strcmp(cmd, "1")) { 261 mutex_lock(&cp->lock); 262 error = s390_vary_chpid(cp->chpid, 1); 263 mutex_unlock(&cp->lock); 264 } else if (!strncasecmp(cmd, "off", 3) || !strcmp(cmd, "0")) { 265 mutex_lock(&cp->lock); 266 error = s390_vary_chpid(cp->chpid, 0); 267 mutex_unlock(&cp->lock); 268 } else 269 error = -EINVAL; 270 271 return error < 0 ? error : count; 272 } 273 274 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write); 275 276 static ssize_t chp_configure_show(struct device *dev, 277 struct device_attribute *attr, char *buf) 278 { 279 struct channel_path *cp; 280 int status; 281 282 cp = to_channelpath(dev); 283 status = chp_info_get_status(cp->chpid); 284 if (status < 0) 285 return status; 286 287 return snprintf(buf, PAGE_SIZE, "%d\n", status); 288 } 289 290 static int cfg_wait_idle(void); 291 292 static ssize_t chp_configure_write(struct device *dev, 293 struct device_attribute *attr, 294 const char *buf, size_t count) 295 { 296 struct channel_path *cp; 297 int val; 298 char delim; 299 300 if (sscanf(buf, "%d %c", &val, &delim) != 1) 301 return -EINVAL; 302 if (val != 0 && val != 1) 303 return -EINVAL; 304 cp = to_channelpath(dev); 305 chp_cfg_schedule(cp->chpid, val); 306 cfg_wait_idle(); 307 308 return count; 309 } 310 311 static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write); 312 313 static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr, 314 char *buf) 315 { 316 struct channel_path *chp = to_channelpath(dev); 317 u8 type; 318 319 mutex_lock(&chp->lock); 320 type = chp->desc.desc; 321 mutex_unlock(&chp->lock); 322 return sprintf(buf, "%x\n", type); 323 } 324 325 static DEVICE_ATTR(type, 0444, chp_type_show, NULL); 326 327 static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr, 328 char *buf) 329 { 330 struct channel_path *chp = to_channelpath(dev); 331 332 if (!chp) 333 return 0; 334 if (chp->cmg == -1) /* channel measurements not available */ 335 return sprintf(buf, "unknown\n"); 336 return sprintf(buf, "%x\n", chp->cmg); 337 } 338 339 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL); 340 341 static ssize_t chp_shared_show(struct device *dev, 342 struct device_attribute *attr, char *buf) 343 { 344 struct channel_path *chp = to_channelpath(dev); 345 346 if (!chp) 347 return 0; 348 if (chp->shared == -1) /* channel measurements not available */ 349 return sprintf(buf, "unknown\n"); 350 return sprintf(buf, "%x\n", chp->shared); 351 } 352 353 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL); 354 355 static ssize_t chp_chid_show(struct device *dev, struct device_attribute *attr, 356 char *buf) 357 { 358 struct channel_path *chp = to_channelpath(dev); 359 ssize_t rc; 360 361 mutex_lock(&chp->lock); 362 if (chp->desc_fmt1.flags & 0x10) 363 rc = sprintf(buf, "%04x\n", chp->desc_fmt1.chid); 364 else 365 rc = 0; 366 mutex_unlock(&chp->lock); 367 368 return rc; 369 } 370 static DEVICE_ATTR(chid, 0444, chp_chid_show, NULL); 371 372 static ssize_t chp_chid_external_show(struct device *dev, 373 struct device_attribute *attr, char *buf) 374 { 375 struct channel_path *chp = to_channelpath(dev); 376 ssize_t rc; 377 378 mutex_lock(&chp->lock); 379 if (chp->desc_fmt1.flags & 0x10) 380 rc = sprintf(buf, "%x\n", chp->desc_fmt1.flags & 0x8 ? 1 : 0); 381 else 382 rc = 0; 383 mutex_unlock(&chp->lock); 384 385 return rc; 386 } 387 static DEVICE_ATTR(chid_external, 0444, chp_chid_external_show, NULL); 388 389 static struct attribute *chp_attrs[] = { 390 &dev_attr_status.attr, 391 &dev_attr_configure.attr, 392 &dev_attr_type.attr, 393 &dev_attr_cmg.attr, 394 &dev_attr_shared.attr, 395 &dev_attr_chid.attr, 396 &dev_attr_chid_external.attr, 397 NULL, 398 }; 399 static struct attribute_group chp_attr_group = { 400 .attrs = chp_attrs, 401 }; 402 static const struct attribute_group *chp_attr_groups[] = { 403 &chp_attr_group, 404 NULL, 405 }; 406 407 static void chp_release(struct device *dev) 408 { 409 struct channel_path *cp; 410 411 cp = to_channelpath(dev); 412 kfree(cp); 413 } 414 415 /** 416 * chp_update_desc - update channel-path description 417 * @chp - channel-path 418 * 419 * Update the channel-path description of the specified channel-path 420 * including channel measurement related information. 421 * Return zero on success, non-zero otherwise. 422 */ 423 int chp_update_desc(struct channel_path *chp) 424 { 425 int rc; 426 427 rc = chsc_determine_base_channel_path_desc(chp->chpid, &chp->desc); 428 if (rc) 429 return rc; 430 431 rc = chsc_determine_fmt1_channel_path_desc(chp->chpid, &chp->desc_fmt1); 432 if (rc) 433 return rc; 434 435 return chsc_get_channel_measurement_chars(chp); 436 } 437 438 /** 439 * chp_new - register a new channel-path 440 * @chpid - channel-path ID 441 * 442 * Create and register data structure representing new channel-path. Return 443 * zero on success, non-zero otherwise. 444 */ 445 int chp_new(struct chp_id chpid) 446 { 447 struct channel_path *chp; 448 int ret; 449 450 if (chp_is_registered(chpid)) 451 return 0; 452 chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL); 453 if (!chp) 454 return -ENOMEM; 455 456 /* fill in status, etc. */ 457 chp->chpid = chpid; 458 chp->state = 1; 459 chp->dev.parent = &channel_subsystems[chpid.cssid]->device; 460 chp->dev.groups = chp_attr_groups; 461 chp->dev.release = chp_release; 462 mutex_init(&chp->lock); 463 464 /* Obtain channel path description and fill it in. */ 465 ret = chp_update_desc(chp); 466 if (ret) 467 goto out_free; 468 if ((chp->desc.flags & 0x80) == 0) { 469 ret = -ENODEV; 470 goto out_free; 471 } 472 dev_set_name(&chp->dev, "chp%x.%02x", chpid.cssid, chpid.id); 473 474 /* make it known to the system */ 475 ret = device_register(&chp->dev); 476 if (ret) { 477 CIO_MSG_EVENT(0, "Could not register chp%x.%02x: %d\n", 478 chpid.cssid, chpid.id, ret); 479 put_device(&chp->dev); 480 goto out; 481 } 482 mutex_lock(&channel_subsystems[chpid.cssid]->mutex); 483 if (channel_subsystems[chpid.cssid]->cm_enabled) { 484 ret = chp_add_cmg_attr(chp); 485 if (ret) { 486 device_unregister(&chp->dev); 487 mutex_unlock(&channel_subsystems[chpid.cssid]->mutex); 488 goto out; 489 } 490 } 491 channel_subsystems[chpid.cssid]->chps[chpid.id] = chp; 492 mutex_unlock(&channel_subsystems[chpid.cssid]->mutex); 493 goto out; 494 out_free: 495 kfree(chp); 496 out: 497 return ret; 498 } 499 500 /** 501 * chp_get_chp_desc - return newly allocated channel-path description 502 * @chpid: channel-path ID 503 * 504 * On success return a newly allocated copy of the channel-path description 505 * data associated with the given channel-path ID. Return %NULL on error. 506 */ 507 struct channel_path_desc *chp_get_chp_desc(struct chp_id chpid) 508 { 509 struct channel_path *chp; 510 struct channel_path_desc *desc; 511 512 chp = chpid_to_chp(chpid); 513 if (!chp) 514 return NULL; 515 desc = kmalloc(sizeof(struct channel_path_desc), GFP_KERNEL); 516 if (!desc) 517 return NULL; 518 519 mutex_lock(&chp->lock); 520 memcpy(desc, &chp->desc, sizeof(struct channel_path_desc)); 521 mutex_unlock(&chp->lock); 522 return desc; 523 } 524 525 /** 526 * chp_process_crw - process channel-path status change 527 * @crw0: channel report-word to handler 528 * @crw1: second channel-report word (always NULL) 529 * @overflow: crw overflow indication 530 * 531 * Handle channel-report-words indicating that the status of a channel-path 532 * has changed. 533 */ 534 static void chp_process_crw(struct crw *crw0, struct crw *crw1, 535 int overflow) 536 { 537 struct chp_id chpid; 538 539 if (overflow) { 540 css_schedule_eval_all(); 541 return; 542 } 543 CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, " 544 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n", 545 crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc, 546 crw0->erc, crw0->rsid); 547 /* 548 * Check for solicited machine checks. These are 549 * created by reset channel path and need not be 550 * handled here. 551 */ 552 if (crw0->slct) { 553 CIO_CRW_EVENT(2, "solicited machine check for " 554 "channel path %02X\n", crw0->rsid); 555 return; 556 } 557 chp_id_init(&chpid); 558 chpid.id = crw0->rsid; 559 switch (crw0->erc) { 560 case CRW_ERC_IPARM: /* Path has come. */ 561 if (!chp_is_registered(chpid)) 562 chp_new(chpid); 563 chsc_chp_online(chpid); 564 break; 565 case CRW_ERC_PERRI: /* Path has gone. */ 566 case CRW_ERC_PERRN: 567 chsc_chp_offline(chpid); 568 break; 569 default: 570 CIO_CRW_EVENT(2, "Don't know how to handle erc=%x\n", 571 crw0->erc); 572 } 573 } 574 575 int chp_ssd_get_mask(struct chsc_ssd_info *ssd, struct chp_link *link) 576 { 577 int i; 578 int mask; 579 580 for (i = 0; i < 8; i++) { 581 mask = 0x80 >> i; 582 if (!(ssd->path_mask & mask)) 583 continue; 584 if (!chp_id_is_equal(&ssd->chpid[i], &link->chpid)) 585 continue; 586 if ((ssd->fla_valid_mask & mask) && 587 ((ssd->fla[i] & link->fla_mask) != link->fla)) 588 continue; 589 return mask; 590 } 591 return 0; 592 } 593 EXPORT_SYMBOL_GPL(chp_ssd_get_mask); 594 595 static inline int info_bit_num(struct chp_id id) 596 { 597 return id.id + id.cssid * (__MAX_CHPID + 1); 598 } 599 600 /* Force chp_info refresh on next call to info_validate(). */ 601 static void info_expire(void) 602 { 603 mutex_lock(&info_lock); 604 chp_info_expires = jiffies - 1; 605 mutex_unlock(&info_lock); 606 } 607 608 /* Ensure that chp_info is up-to-date. */ 609 static int info_update(void) 610 { 611 int rc; 612 613 mutex_lock(&info_lock); 614 rc = 0; 615 if (time_after(jiffies, chp_info_expires)) { 616 /* Data is too old, update. */ 617 rc = sclp_chp_read_info(&chp_info); 618 chp_info_expires = jiffies + CHP_INFO_UPDATE_INTERVAL ; 619 } 620 mutex_unlock(&info_lock); 621 622 return rc; 623 } 624 625 /** 626 * chp_info_get_status - retrieve configure status of a channel-path 627 * @chpid: channel-path ID 628 * 629 * On success, return 0 for standby, 1 for configured, 2 for reserved, 630 * 3 for not recognized. Return negative error code on error. 631 */ 632 int chp_info_get_status(struct chp_id chpid) 633 { 634 int rc; 635 int bit; 636 637 rc = info_update(); 638 if (rc) 639 return rc; 640 641 bit = info_bit_num(chpid); 642 mutex_lock(&info_lock); 643 if (!chp_test_bit(chp_info.recognized, bit)) 644 rc = CHP_STATUS_NOT_RECOGNIZED; 645 else if (chp_test_bit(chp_info.configured, bit)) 646 rc = CHP_STATUS_CONFIGURED; 647 else if (chp_test_bit(chp_info.standby, bit)) 648 rc = CHP_STATUS_STANDBY; 649 else 650 rc = CHP_STATUS_RESERVED; 651 mutex_unlock(&info_lock); 652 653 return rc; 654 } 655 656 /* Return configure task for chpid. */ 657 static enum cfg_task_t cfg_get_task(struct chp_id chpid) 658 { 659 return chp_cfg_task[chpid.cssid][chpid.id]; 660 } 661 662 /* Set configure task for chpid. */ 663 static void cfg_set_task(struct chp_id chpid, enum cfg_task_t cfg) 664 { 665 chp_cfg_task[chpid.cssid][chpid.id] = cfg; 666 } 667 668 /* Perform one configure/deconfigure request. Reschedule work function until 669 * last request. */ 670 static void cfg_func(struct work_struct *work) 671 { 672 struct chp_id chpid; 673 enum cfg_task_t t; 674 int rc; 675 676 mutex_lock(&cfg_lock); 677 t = cfg_none; 678 chp_id_for_each(&chpid) { 679 t = cfg_get_task(chpid); 680 if (t != cfg_none) { 681 cfg_set_task(chpid, cfg_none); 682 break; 683 } 684 } 685 mutex_unlock(&cfg_lock); 686 687 switch (t) { 688 case cfg_configure: 689 rc = sclp_chp_configure(chpid); 690 if (rc) 691 CIO_MSG_EVENT(2, "chp: sclp_chp_configure(%x.%02x)=" 692 "%d\n", chpid.cssid, chpid.id, rc); 693 else { 694 info_expire(); 695 chsc_chp_online(chpid); 696 } 697 break; 698 case cfg_deconfigure: 699 rc = sclp_chp_deconfigure(chpid); 700 if (rc) 701 CIO_MSG_EVENT(2, "chp: sclp_chp_deconfigure(%x.%02x)=" 702 "%d\n", chpid.cssid, chpid.id, rc); 703 else { 704 info_expire(); 705 chsc_chp_offline(chpid); 706 } 707 break; 708 case cfg_none: 709 /* Get updated information after last change. */ 710 info_update(); 711 mutex_lock(&cfg_lock); 712 cfg_busy = 0; 713 mutex_unlock(&cfg_lock); 714 wake_up_interruptible(&cfg_wait_queue); 715 return; 716 } 717 queue_work(chp_wq, &cfg_work); 718 } 719 720 /** 721 * chp_cfg_schedule - schedule chpid configuration request 722 * @chpid - channel-path ID 723 * @configure - Non-zero for configure, zero for deconfigure 724 * 725 * Schedule a channel-path configuration/deconfiguration request. 726 */ 727 void chp_cfg_schedule(struct chp_id chpid, int configure) 728 { 729 CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid.cssid, chpid.id, 730 configure); 731 mutex_lock(&cfg_lock); 732 cfg_set_task(chpid, configure ? cfg_configure : cfg_deconfigure); 733 cfg_busy = 1; 734 mutex_unlock(&cfg_lock); 735 queue_work(chp_wq, &cfg_work); 736 } 737 738 /** 739 * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request 740 * @chpid - channel-path ID 741 * 742 * Cancel an active channel-path deconfiguration request if it has not yet 743 * been performed. 744 */ 745 void chp_cfg_cancel_deconfigure(struct chp_id chpid) 746 { 747 CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid.cssid, chpid.id); 748 mutex_lock(&cfg_lock); 749 if (cfg_get_task(chpid) == cfg_deconfigure) 750 cfg_set_task(chpid, cfg_none); 751 mutex_unlock(&cfg_lock); 752 } 753 754 static int cfg_wait_idle(void) 755 { 756 if (wait_event_interruptible(cfg_wait_queue, !cfg_busy)) 757 return -ERESTARTSYS; 758 return 0; 759 } 760 761 static int __init chp_init(void) 762 { 763 struct chp_id chpid; 764 int ret; 765 766 ret = crw_register_handler(CRW_RSC_CPATH, chp_process_crw); 767 if (ret) 768 return ret; 769 chp_wq = create_singlethread_workqueue("cio_chp"); 770 if (!chp_wq) { 771 crw_unregister_handler(CRW_RSC_CPATH); 772 return -ENOMEM; 773 } 774 INIT_WORK(&cfg_work, cfg_func); 775 init_waitqueue_head(&cfg_wait_queue); 776 if (info_update()) 777 return 0; 778 /* Register available channel-paths. */ 779 chp_id_for_each(&chpid) { 780 if (chp_info_get_status(chpid) != CHP_STATUS_NOT_RECOGNIZED) 781 chp_new(chpid); 782 } 783 784 return 0; 785 } 786 787 subsys_initcall(chp_init); 788