1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright IBM Corp. 1999, 2010 4 * Author(s): Cornelia Huck (cornelia.huck@de.ibm.com) 5 * Arnd Bergmann (arndb@de.ibm.com) 6 * Peter Oberparleiter <peter.oberparleiter@de.ibm.com> 7 */ 8 9 #include <linux/bug.h> 10 #include <linux/workqueue.h> 11 #include <linux/spinlock.h> 12 #include <linux/export.h> 13 #include <linux/sched.h> 14 #include <linux/init.h> 15 #include <linux/jiffies.h> 16 #include <linux/wait.h> 17 #include <linux/mutex.h> 18 #include <linux/errno.h> 19 #include <linux/slab.h> 20 #include <asm/chpid.h> 21 #include <asm/sclp.h> 22 #include <asm/crw.h> 23 24 #include "cio.h" 25 #include "css.h" 26 #include "ioasm.h" 27 #include "cio_debug.h" 28 #include "chp.h" 29 30 #define to_channelpath(device) container_of(device, struct channel_path, dev) 31 #define CHP_INFO_UPDATE_INTERVAL 1*HZ 32 33 enum cfg_task_t { 34 cfg_none, 35 cfg_configure, 36 cfg_deconfigure 37 }; 38 39 /* Map for pending configure tasks. */ 40 static enum cfg_task_t chp_cfg_task[__MAX_CSSID + 1][__MAX_CHPID + 1]; 41 static DEFINE_SPINLOCK(cfg_lock); 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struct sclp_chp_info chp_info; 45 static DEFINE_MUTEX(info_lock); 46 47 /* Time after which channel-path status may be outdated.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 static struct work_struct cfg_work; 51 52 /* Wait queue for configure completion events. */ 53 static DECLARE_WAIT_QUEUE_HEAD(cfg_wait_queue); 54 55 /* Set vary state for given chpid. */ 56 static void set_chp_logically_online(struct chp_id chpid, int onoff) 57 { 58 chpid_to_chp(chpid)->state = onoff; 59 } 60 61 /* On success return 0 if channel-path is varied offline, 1 if it is varied 62 * online. Return -ENODEV if channel-path is not registered. */ 63 int chp_get_status(struct chp_id chpid) 64 { 65 return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV); 66 } 67 68 /** 69 * chp_get_sch_opm - return opm for subchannel 70 * @sch: subchannel 71 * 72 * Calculate and return the operational path mask (opm) based on the chpids 73 * used by the subchannel and the status of the associated channel-paths. 74 */ 75 u8 chp_get_sch_opm(struct subchannel *sch) 76 { 77 struct chp_id chpid; 78 int opm; 79 int i; 80 81 opm = 0; 82 chp_id_init(&chpid); 83 for (i = 0; i < 8; i++) { 84 opm <<= 1; 85 chpid.id = sch->schib.pmcw.chpid[i]; 86 if (chp_get_status(chpid) != 0) 87 opm |= 1; 88 } 89 return opm; 90 } 91 EXPORT_SYMBOL_GPL(chp_get_sch_opm); 92 93 /** 94 * chp_is_registered - check if a channel-path is registered 95 * @chpid: channel-path ID 96 * 97 * Return non-zero if a channel-path with the given chpid is registered, 98 * zero otherwise. 99 */ 100 int chp_is_registered(struct chp_id chpid) 101 { 102 return chpid_to_chp(chpid) != NULL; 103 } 104 105 /* 106 * Function: s390_vary_chpid 107 * Varies the specified chpid online or offline 108 */ 109 static int s390_vary_chpid(struct chp_id chpid, int on) 110 { 111 char dbf_text[15]; 112 int status; 113 114 sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid, 115 chpid.id); 116 CIO_TRACE_EVENT(2, dbf_text); 117 118 status = chp_get_status(chpid); 119 if (!on && !status) 120 return 0; 121 122 set_chp_logically_online(chpid, on); 123 chsc_chp_vary(chpid, on); 124 return 0; 125 } 126 127 /* 128 * Channel measurement related functions 129 */ 130 static ssize_t measurement_chars_read(struct file *filp, struct kobject *kobj, 131 struct bin_attribute *bin_attr, 132 char *buf, loff_t off, size_t count) 133 { 134 struct channel_path *chp; 135 struct device *device; 136 137 device = kobj_to_dev(kobj); 138 chp = to_channelpath(device); 139 if (chp->cmg == -1) 140 return 0; 141 142 return memory_read_from_buffer(buf, count, &off, &chp->cmg_chars, 143 sizeof(chp->cmg_chars)); 144 } 145 static BIN_ATTR_ADMIN_RO(measurement_chars, sizeof(struct cmg_chars)); 146 147 static ssize_t measurement_chars_full_read(struct file *filp, 148 struct kobject *kobj, 149 struct bin_attribute *bin_attr, 150 char *buf, loff_t off, size_t count) 151 { 152 struct channel_path *chp = to_channelpath(kobj_to_dev(kobj)); 153 154 return memory_read_from_buffer(buf, count, &off, &chp->cmcb, 155 sizeof(chp->cmcb)); 156 } 157 static BIN_ATTR_ADMIN_RO(measurement_chars_full, sizeof(struct cmg_cmcb)); 158 159 static ssize_t chp_measurement_copy_block(void *buf, loff_t off, size_t count, 160 struct kobject *kobj, bool extended) 161 { 162 struct channel_path *chp; 163 struct channel_subsystem *css; 164 struct device *device; 165 unsigned int size; 166 void *area, *entry; 167 int id, idx; 168 169 device = kobj_to_dev(kobj); 170 chp = to_channelpath(device); 171 css = to_css(chp->dev.parent); 172 id = chp->chpid.id; 173 174 if (extended) { 175 /* Check if extended measurement data is available. */ 176 if (!chp->extended) 177 return 0; 178 179 size = sizeof(struct cmg_ext_entry); 180 area = css->ecub[id / CSS_ECUES_PER_PAGE]; 181 idx = id % CSS_ECUES_PER_PAGE; 182 } else { 183 size = sizeof(struct cmg_entry); 184 area = css->cub[id / CSS_CUES_PER_PAGE]; 185 idx = id % CSS_CUES_PER_PAGE; 186 } 187 entry = area + (idx * size); 188 189 /* Only allow single reads. */ 190 if (off || count < size) 191 return 0; 192 193 memcpy(buf, entry, size); 194 195 return size; 196 } 197 198 static ssize_t measurement_read(struct file *filp, struct kobject *kobj, 199 struct bin_attribute *bin_attr, 200 char *buf, loff_t off, size_t count) 201 { 202 return chp_measurement_copy_block(buf, off, count, kobj, false); 203 } 204 static BIN_ATTR_ADMIN_RO(measurement, sizeof(struct cmg_entry)); 205 206 static ssize_t ext_measurement_read(struct file *filp, struct kobject *kobj, 207 struct bin_attribute *bin_attr, 208 char *buf, loff_t off, size_t count) 209 { 210 return chp_measurement_copy_block(buf, off, count, kobj, true); 211 } 212 static BIN_ATTR_ADMIN_RO(ext_measurement, sizeof(struct cmg_ext_entry)); 213 214 static struct bin_attribute *measurement_attrs[] = { 215 &bin_attr_measurement_chars, 216 &bin_attr_measurement_chars_full, 217 &bin_attr_measurement, 218 &bin_attr_ext_measurement, 219 NULL, 220 }; 221 BIN_ATTRIBUTE_GROUPS(measurement); 222 223 void chp_remove_cmg_attr(struct channel_path *chp) 224 { 225 device_remove_groups(&chp->dev, measurement_groups); 226 } 227 228 int chp_add_cmg_attr(struct channel_path *chp) 229 { 230 return device_add_groups(&chp->dev, measurement_groups); 231 } 232 233 /* 234 * Files for the channel path entries. 235 */ 236 static ssize_t chp_status_show(struct device *dev, 237 struct device_attribute *attr, char *buf) 238 { 239 struct channel_path *chp = to_channelpath(dev); 240 int status; 241 242 mutex_lock(&chp->lock); 243 status = chp->state; 244 mutex_unlock(&chp->lock); 245 246 return status ? sysfs_emit(buf, "online\n") : sysfs_emit(buf, "offline\n"); 247 } 248 249 static ssize_t chp_status_write(struct device *dev, 250 struct device_attribute *attr, 251 const char *buf, size_t count) 252 { 253 struct channel_path *cp = to_channelpath(dev); 254 char cmd[10]; 255 int num_args; 256 int error; 257 258 num_args = sscanf(buf, "%5s", cmd); 259 if (!num_args) 260 return count; 261 262 /* Wait until previous actions have settled. */ 263 css_wait_for_slow_path(); 264 265 if (!strncasecmp(cmd, "on", 2) || !strcmp(cmd, "1")) { 266 mutex_lock(&cp->lock); 267 error = s390_vary_chpid(cp->chpid, 1); 268 mutex_unlock(&cp->lock); 269 } else if (!strncasecmp(cmd, "off", 3) || !strcmp(cmd, "0")) { 270 mutex_lock(&cp->lock); 271 error = s390_vary_chpid(cp->chpid, 0); 272 mutex_unlock(&cp->lock); 273 } else 274 error = -EINVAL; 275 276 return error < 0 ? error : count; 277 } 278 279 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write); 280 281 static ssize_t chp_configure_show(struct device *dev, 282 struct device_attribute *attr, char *buf) 283 { 284 struct channel_path *cp; 285 int status; 286 287 cp = to_channelpath(dev); 288 status = chp_info_get_status(cp->chpid); 289 if (status < 0) 290 return status; 291 292 return sysfs_emit(buf, "%d\n", status); 293 } 294 295 static int cfg_wait_idle(void); 296 297 static ssize_t chp_configure_write(struct device *dev, 298 struct device_attribute *attr, 299 const char *buf, size_t count) 300 { 301 struct channel_path *cp; 302 int val; 303 char delim; 304 305 if (sscanf(buf, "%d %c", &val, &delim) != 1) 306 return -EINVAL; 307 if (val != 0 && val != 1) 308 return -EINVAL; 309 cp = to_channelpath(dev); 310 chp_cfg_schedule(cp->chpid, val); 311 cfg_wait_idle(); 312 313 return count; 314 } 315 316 static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write); 317 318 static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr, 319 char *buf) 320 { 321 struct channel_path *chp = to_channelpath(dev); 322 u8 type; 323 324 mutex_lock(&chp->lock); 325 type = chp->desc.desc; 326 mutex_unlock(&chp->lock); 327 return sysfs_emit(buf, "%x\n", type); 328 } 329 330 static DEVICE_ATTR(type, 0444, chp_type_show, NULL); 331 332 static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr, 333 char *buf) 334 { 335 struct channel_path *chp = to_channelpath(dev); 336 337 if (!chp) 338 return 0; 339 if (chp->cmg == -1) /* channel measurements not available */ 340 return sysfs_emit(buf, "unknown\n"); 341 return sysfs_emit(buf, "%d\n", chp->cmg); 342 } 343 344 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL); 345 346 static ssize_t chp_shared_show(struct device *dev, 347 struct device_attribute *attr, char *buf) 348 { 349 struct channel_path *chp = to_channelpath(dev); 350 351 if (!chp) 352 return 0; 353 if (chp->shared == -1) /* channel measurements not available */ 354 return sysfs_emit(buf, "unknown\n"); 355 return sysfs_emit(buf, "%x\n", chp->shared); 356 } 357 358 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL); 359 360 static ssize_t chp_chid_show(struct device *dev, struct device_attribute *attr, 361 char *buf) 362 { 363 struct channel_path *chp = to_channelpath(dev); 364 ssize_t rc; 365 366 mutex_lock(&chp->lock); 367 if (chp->desc_fmt1.flags & 0x10) 368 rc = sysfs_emit(buf, "%04x\n", chp->desc_fmt1.chid); 369 else 370 rc = 0; 371 mutex_unlock(&chp->lock); 372 373 return rc; 374 } 375 static DEVICE_ATTR(chid, 0444, chp_chid_show, NULL); 376 377 static ssize_t chp_chid_external_show(struct device *dev, 378 struct device_attribute *attr, char *buf) 379 { 380 struct channel_path *chp = to_channelpath(dev); 381 ssize_t rc; 382 383 mutex_lock(&chp->lock); 384 if (chp->desc_fmt1.flags & 0x10) 385 rc = sysfs_emit(buf, "%x\n", chp->desc_fmt1.flags & 0x8 ? 1 : 0); 386 else 387 rc = 0; 388 mutex_unlock(&chp->lock); 389 390 return rc; 391 } 392 static DEVICE_ATTR(chid_external, 0444, chp_chid_external_show, NULL); 393 394 static ssize_t chp_esc_show(struct device *dev, 395 struct device_attribute *attr, char *buf) 396 { 397 struct channel_path *chp = to_channelpath(dev); 398 ssize_t rc; 399 400 mutex_lock(&chp->lock); 401 rc = sysfs_emit(buf, "%x\n", chp->desc_fmt1.esc); 402 mutex_unlock(&chp->lock); 403 404 return rc; 405 } 406 static DEVICE_ATTR(esc, 0444, chp_esc_show, NULL); 407 408 static char apply_max_suffix(unsigned long *value, unsigned long base) 409 { 410 static char suffixes[] = { 0, 'K', 'M', 'G', 'T' }; 411 int i; 412 413 for (i = 0; i < ARRAY_SIZE(suffixes) - 1; i++) { 414 if (*value < base || *value % base != 0) 415 break; 416 *value /= base; 417 } 418 419 return suffixes[i]; 420 } 421 422 static ssize_t speed_bps_show(struct device *dev, 423 struct device_attribute *attr, char *buf) 424 { 425 struct channel_path *chp = to_channelpath(dev); 426 unsigned long speed = chp->speed; 427 char suffix; 428 429 suffix = apply_max_suffix(&speed, 1000); 430 431 return suffix ? sysfs_emit(buf, "%lu%c\n", speed, suffix) : 432 sysfs_emit(buf, "%lu\n", speed); 433 } 434 435 static DEVICE_ATTR_RO(speed_bps); 436 437 static ssize_t util_string_read(struct file *filp, struct kobject *kobj, 438 struct bin_attribute *attr, char *buf, 439 loff_t off, size_t count) 440 { 441 struct channel_path *chp = to_channelpath(kobj_to_dev(kobj)); 442 ssize_t rc; 443 444 mutex_lock(&chp->lock); 445 rc = memory_read_from_buffer(buf, count, &off, chp->desc_fmt3.util_str, 446 sizeof(chp->desc_fmt3.util_str)); 447 mutex_unlock(&chp->lock); 448 449 return rc; 450 } 451 static BIN_ATTR_RO(util_string, 452 sizeof(((struct channel_path_desc_fmt3 *)0)->util_str)); 453 454 static struct bin_attribute *chp_bin_attrs[] = { 455 &bin_attr_util_string, 456 NULL, 457 }; 458 459 static struct attribute *chp_attrs[] = { 460 &dev_attr_status.attr, 461 &dev_attr_configure.attr, 462 &dev_attr_type.attr, 463 &dev_attr_cmg.attr, 464 &dev_attr_shared.attr, 465 &dev_attr_chid.attr, 466 &dev_attr_chid_external.attr, 467 &dev_attr_esc.attr, 468 &dev_attr_speed_bps.attr, 469 NULL, 470 }; 471 static struct attribute_group chp_attr_group = { 472 .attrs = chp_attrs, 473 .bin_attrs = chp_bin_attrs, 474 }; 475 static const struct attribute_group *chp_attr_groups[] = { 476 &chp_attr_group, 477 NULL, 478 }; 479 480 static void chp_release(struct device *dev) 481 { 482 struct channel_path *cp; 483 484 cp = to_channelpath(dev); 485 kfree(cp); 486 } 487 488 /** 489 * chp_update_desc - update channel-path description 490 * @chp: channel-path 491 * 492 * Update the channel-path description of the specified channel-path 493 * including channel measurement related information. 494 * Return zero on success, non-zero otherwise. 495 */ 496 int chp_update_desc(struct channel_path *chp) 497 { 498 int rc; 499 500 rc = chsc_determine_fmt0_channel_path_desc(chp->chpid, &chp->desc); 501 if (rc) 502 return rc; 503 504 /* 505 * Fetching the following data is optional. Not all machines or 506 * hypervisors implement the required chsc commands. 507 */ 508 chsc_determine_fmt1_channel_path_desc(chp->chpid, &chp->desc_fmt1); 509 chsc_determine_fmt3_channel_path_desc(chp->chpid, &chp->desc_fmt3); 510 chsc_get_channel_measurement_chars(chp); 511 512 return 0; 513 } 514 515 /** 516 * chp_new - register a new channel-path 517 * @chpid: channel-path ID 518 * 519 * Create and register data structure representing new channel-path. Return 520 * zero on success, non-zero otherwise. 521 */ 522 int chp_new(struct chp_id chpid) 523 { 524 struct channel_subsystem *css = css_by_id(chpid.cssid); 525 struct channel_path *chp; 526 int ret = 0; 527 528 mutex_lock(&css->mutex); 529 if (chp_is_registered(chpid)) 530 goto out; 531 532 chp = kzalloc(sizeof(struct channel_path), GFP_KERNEL); 533 if (!chp) { 534 ret = -ENOMEM; 535 goto out; 536 } 537 /* fill in status, etc. */ 538 chp->chpid = chpid; 539 chp->state = 1; 540 chp->dev.parent = &css->device; 541 chp->dev.groups = chp_attr_groups; 542 chp->dev.release = chp_release; 543 mutex_init(&chp->lock); 544 545 /* Obtain channel path description and fill it in. */ 546 ret = chp_update_desc(chp); 547 if (ret) 548 goto out_free; 549 if ((chp->desc.flags & 0x80) == 0) { 550 ret = -ENODEV; 551 goto out_free; 552 } 553 dev_set_name(&chp->dev, "chp%x.%02x", chpid.cssid, chpid.id); 554 555 /* make it known to the system */ 556 ret = device_register(&chp->dev); 557 if (ret) { 558 CIO_MSG_EVENT(0, "Could not register chp%x.%02x: %d\n", 559 chpid.cssid, chpid.id, ret); 560 put_device(&chp->dev); 561 goto out; 562 } 563 564 if (css->cm_enabled) { 565 ret = chp_add_cmg_attr(chp); 566 if (ret) { 567 device_unregister(&chp->dev); 568 goto out; 569 } 570 } 571 css->chps[chpid.id] = chp; 572 goto out; 573 out_free: 574 kfree(chp); 575 out: 576 mutex_unlock(&css->mutex); 577 return ret; 578 } 579 580 /** 581 * chp_get_chp_desc - return newly allocated channel-path description 582 * @chpid: channel-path ID 583 * 584 * On success return a newly allocated copy of the channel-path description 585 * data associated with the given channel-path ID. Return %NULL on error. 586 */ 587 struct channel_path_desc_fmt0 *chp_get_chp_desc(struct chp_id chpid) 588 { 589 struct channel_path *chp; 590 struct channel_path_desc_fmt0 *desc; 591 592 chp = chpid_to_chp(chpid); 593 if (!chp) 594 return NULL; 595 desc = kmalloc(sizeof(*desc), GFP_KERNEL); 596 if (!desc) 597 return NULL; 598 599 mutex_lock(&chp->lock); 600 memcpy(desc, &chp->desc, sizeof(*desc)); 601 mutex_unlock(&chp->lock); 602 return desc; 603 } 604 605 /** 606 * chp_process_crw - process channel-path status change 607 * @crw0: channel report-word to handler 608 * @crw1: second channel-report word (always NULL) 609 * @overflow: crw overflow indication 610 * 611 * Handle channel-report-words indicating that the status of a channel-path 612 * has changed. 613 */ 614 static void chp_process_crw(struct crw *crw0, struct crw *crw1, 615 int overflow) 616 { 617 struct chp_id chpid; 618 619 if (overflow) { 620 css_schedule_eval_all(); 621 return; 622 } 623 CIO_CRW_EVENT(2, "CRW reports slct=%d, oflw=%d, " 624 "chn=%d, rsc=%X, anc=%d, erc=%X, rsid=%X\n", 625 crw0->slct, crw0->oflw, crw0->chn, crw0->rsc, crw0->anc, 626 crw0->erc, crw0->rsid); 627 /* 628 * Check for solicited machine checks. These are 629 * created by reset channel path and need not be 630 * handled here. 631 */ 632 if (crw0->slct) { 633 CIO_CRW_EVENT(2, "solicited machine check for " 634 "channel path %02X\n", crw0->rsid); 635 return; 636 } 637 chp_id_init(&chpid); 638 chpid.id = crw0->rsid; 639 switch (crw0->erc) { 640 case CRW_ERC_IPARM: /* Path has come. */ 641 case CRW_ERC_INIT: 642 chp_new(chpid); 643 chsc_chp_online(chpid); 644 break; 645 case CRW_ERC_PERRI: /* Path has gone. */ 646 case CRW_ERC_PERRN: 647 chsc_chp_offline(chpid); 648 break; 649 default: 650 CIO_CRW_EVENT(2, "Don't know how to handle erc=%x\n", 651 crw0->erc); 652 } 653 } 654 655 int chp_ssd_get_mask(struct chsc_ssd_info *ssd, struct chp_link *link) 656 { 657 int i; 658 int mask; 659 660 for (i = 0; i < 8; i++) { 661 mask = 0x80 >> i; 662 if (!(ssd->path_mask & mask)) 663 continue; 664 if (!chp_id_is_equal(&ssd->chpid[i], &link->chpid)) 665 continue; 666 if ((ssd->fla_valid_mask & mask) && 667 ((ssd->fla[i] & link->fla_mask) != link->fla)) 668 continue; 669 return mask; 670 } 671 return 0; 672 } 673 EXPORT_SYMBOL_GPL(chp_ssd_get_mask); 674 675 static inline int info_bit_num(struct chp_id id) 676 { 677 return id.id + id.cssid * (__MAX_CHPID + 1); 678 } 679 680 /* Force chp_info refresh on next call to info_validate(). */ 681 static void info_expire(void) 682 { 683 mutex_lock(&info_lock); 684 chp_info_expires = jiffies - 1; 685 mutex_unlock(&info_lock); 686 } 687 688 /* Ensure that chp_info is up-to-date. */ 689 static int info_update(void) 690 { 691 int rc; 692 693 mutex_lock(&info_lock); 694 rc = 0; 695 if (time_after(jiffies, chp_info_expires)) { 696 /* Data is too old, update. */ 697 rc = sclp_chp_read_info(&chp_info); 698 chp_info_expires = jiffies + CHP_INFO_UPDATE_INTERVAL ; 699 } 700 mutex_unlock(&info_lock); 701 702 return rc; 703 } 704 705 /** 706 * chp_info_get_status - retrieve configure status of a channel-path 707 * @chpid: channel-path ID 708 * 709 * On success, return 0 for standby, 1 for configured, 2 for reserved, 710 * 3 for not recognized. Return negative error code on error. 711 */ 712 int chp_info_get_status(struct chp_id chpid) 713 { 714 int rc; 715 int bit; 716 717 rc = info_update(); 718 if (rc) 719 return rc; 720 721 bit = info_bit_num(chpid); 722 mutex_lock(&info_lock); 723 if (!chp_test_bit(chp_info.recognized, bit)) 724 rc = CHP_STATUS_NOT_RECOGNIZED; 725 else if (chp_test_bit(chp_info.configured, bit)) 726 rc = CHP_STATUS_CONFIGURED; 727 else if (chp_test_bit(chp_info.standby, bit)) 728 rc = CHP_STATUS_STANDBY; 729 else 730 rc = CHP_STATUS_RESERVED; 731 mutex_unlock(&info_lock); 732 733 return rc; 734 } 735 736 /* Return configure task for chpid. */ 737 static enum cfg_task_t cfg_get_task(struct chp_id chpid) 738 { 739 return chp_cfg_task[chpid.cssid][chpid.id]; 740 } 741 742 /* Set configure task for chpid. */ 743 static void cfg_set_task(struct chp_id chpid, enum cfg_task_t cfg) 744 { 745 chp_cfg_task[chpid.cssid][chpid.id] = cfg; 746 } 747 748 /* Fetch the first configure task. Set chpid accordingly. */ 749 static enum cfg_task_t chp_cfg_fetch_task(struct chp_id *chpid) 750 { 751 enum cfg_task_t t = cfg_none; 752 753 chp_id_for_each(chpid) { 754 t = cfg_get_task(*chpid); 755 if (t != cfg_none) 756 break; 757 } 758 759 return t; 760 } 761 762 /* Perform one configure/deconfigure request. Reschedule work function until 763 * last request. */ 764 static void cfg_func(struct work_struct *work) 765 { 766 struct chp_id chpid; 767 enum cfg_task_t t; 768 int rc; 769 770 spin_lock(&cfg_lock); 771 t = chp_cfg_fetch_task(&chpid); 772 spin_unlock(&cfg_lock); 773 774 switch (t) { 775 case cfg_configure: 776 rc = sclp_chp_configure(chpid); 777 if (rc) 778 CIO_MSG_EVENT(2, "chp: sclp_chp_configure(%x.%02x)=" 779 "%d\n", chpid.cssid, chpid.id, rc); 780 else { 781 info_expire(); 782 chsc_chp_online(chpid); 783 } 784 break; 785 case cfg_deconfigure: 786 rc = sclp_chp_deconfigure(chpid); 787 if (rc) 788 CIO_MSG_EVENT(2, "chp: sclp_chp_deconfigure(%x.%02x)=" 789 "%d\n", chpid.cssid, chpid.id, rc); 790 else { 791 info_expire(); 792 chsc_chp_offline(chpid); 793 } 794 break; 795 case cfg_none: 796 /* Get updated information after last change. */ 797 info_update(); 798 wake_up_interruptible(&cfg_wait_queue); 799 return; 800 } 801 spin_lock(&cfg_lock); 802 if (t == cfg_get_task(chpid)) 803 cfg_set_task(chpid, cfg_none); 804 spin_unlock(&cfg_lock); 805 schedule_work(&cfg_work); 806 } 807 808 /** 809 * chp_cfg_schedule - schedule chpid configuration request 810 * @chpid: channel-path ID 811 * @configure: Non-zero for configure, zero for deconfigure 812 * 813 * Schedule a channel-path configuration/deconfiguration request. 814 */ 815 void chp_cfg_schedule(struct chp_id chpid, int configure) 816 { 817 CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid.cssid, chpid.id, 818 configure); 819 spin_lock(&cfg_lock); 820 cfg_set_task(chpid, configure ? cfg_configure : cfg_deconfigure); 821 spin_unlock(&cfg_lock); 822 schedule_work(&cfg_work); 823 } 824 825 /** 826 * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request 827 * @chpid: channel-path ID 828 * 829 * Cancel an active channel-path deconfiguration request if it has not yet 830 * been performed. 831 */ 832 void chp_cfg_cancel_deconfigure(struct chp_id chpid) 833 { 834 CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid.cssid, chpid.id); 835 spin_lock(&cfg_lock); 836 if (cfg_get_task(chpid) == cfg_deconfigure) 837 cfg_set_task(chpid, cfg_none); 838 spin_unlock(&cfg_lock); 839 } 840 841 static bool cfg_idle(void) 842 { 843 struct chp_id chpid; 844 enum cfg_task_t t; 845 846 spin_lock(&cfg_lock); 847 t = chp_cfg_fetch_task(&chpid); 848 spin_unlock(&cfg_lock); 849 850 return t == cfg_none; 851 } 852 853 static int cfg_wait_idle(void) 854 { 855 if (wait_event_interruptible(cfg_wait_queue, cfg_idle())) 856 return -ERESTARTSYS; 857 return 0; 858 } 859 860 static int __init chp_init(void) 861 { 862 struct chp_id chpid; 863 int state, ret; 864 865 ret = crw_register_handler(CRW_RSC_CPATH, chp_process_crw); 866 if (ret) 867 return ret; 868 INIT_WORK(&cfg_work, cfg_func); 869 if (info_update()) 870 return 0; 871 /* Register available channel-paths. */ 872 chp_id_for_each(&chpid) { 873 state = chp_info_get_status(chpid); 874 if (state == CHP_STATUS_CONFIGURED || 875 state == CHP_STATUS_STANDBY) 876 chp_new(chpid); 877 } 878 879 return 0; 880 } 881 882 subsys_initcall(chp_init); 883