drivers/s390/cio/chp.c

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  47 /* Time after which channel-path status may be outdated.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