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
  42 /* Map for channel-path status. */
  43 static struct sclp_chp_info chp_info;
  44 static DEFINE_MUTEX(info_lock);
  45
  46 /* Time after which channel-path status may be outdated. */
  47 static unsigned long chp_info_expires;
  48
  49 static struct work_struct cfg_work;
  50
  51 /* Wait queue for configure completion events. */
  52 static wait_queue_head_t cfg_wait_queue;
  53
  54 /* Set vary state for given chpid. */
  55 static void set_chp_logically_online(struct chp_id chpid, int onoff)
  56 {
  57         chpid_to_chp(chpid)->state = onoff;
  58 }
  59
  60 /* On success return 0 if channel-path is varied offline, 1 if it is varied
  61  * online. Return -ENODEV if channel-path is not registered. */
  62 int chp_get_status(struct chp_id chpid)
  63 {
  64         return (chpid_to_chp(chpid) ? chpid_to_chp(chpid)->state : -ENODEV);
  65 }
  66
  67 /**
  68  * chp_get_sch_opm - return opm for subchannel
  69  * @sch: subchannel
  70  *
  71  * Calculate and return the operational path mask (opm) based on the chpids
  72  * used by the subchannel and the status of the associated channel-paths.
  73  */
  74 u8 chp_get_sch_opm(struct subchannel *sch)
  75 {
  76         struct chp_id chpid;
  77         int opm;
  78         int i;
  79
  80         opm = 0;
  81         chp_id_init(&chpid);
  82         for (i = 0; i < 8; i++) {
  83                 opm <<= 1;
  84                 chpid.id = sch->schib.pmcw.chpid[i];
  85                 if (chp_get_status(chpid) != 0)
  86                         opm |= 1;
  87         }
  88         return opm;
  89 }
  90 EXPORT_SYMBOL_GPL(chp_get_sch_opm);
  91
  92 /**
  93  * chp_is_registered - check if a channel-path is registered
  94  * @chpid: channel-path ID
  95  *
  96  * Return non-zero if a channel-path with the given chpid is registered,
  97  * zero otherwise.
  98  */
  99 int chp_is_registered(struct chp_id chpid)
 100 {
 101         return chpid_to_chp(chpid) != NULL;
 102 }
 103
 104 /*
 105  * Function: s390_vary_chpid
 106  * Varies the specified chpid online or offline
 107  */
 108 static int s390_vary_chpid(struct chp_id chpid, int on)
 109 {
 110         char dbf_text[15];
 111         int status;
 112
 113         sprintf(dbf_text, on?"varyon%x.%02x":"varyoff%x.%02x", chpid.cssid,
 114                 chpid.id);
 115         CIO_TRACE_EVENT(2, dbf_text);
 116
 117         status = chp_get_status(chpid);
 118         if (!on && !status)
 119                 return 0;
 120
 121         set_chp_logically_online(chpid, on);
 122         chsc_chp_vary(chpid, on);
 123         return 0;
 124 }
 125
 126 /*
 127  * Channel measurement related functions
 128  */
 129 static ssize_t chp_measurement_chars_read(struct file *filp,
 130                                           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 = container_of(kobj, struct device, 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
 146 static struct bin_attribute chp_measurement_chars_attr = {
 147         .attr = {
 148                 .name = "measurement_chars",
 149                 .mode = S_IRUSR,
 150         },
 151         .size = sizeof(struct cmg_chars),
 152         .read = chp_measurement_chars_read,
 153 };
 154
 155 static void chp_measurement_copy_block(struct cmg_entry *buf,
 156                                        struct channel_subsystem *css,
 157                                        struct chp_id chpid)
 158 {
 159         void *area;
 160         struct cmg_entry *entry, reference_buf;
 161         int idx;
 162
 163         if (chpid.id < 128) {
 164                 area = css->cub_addr1;
 165                 idx = chpid.id;
 166         } else {
 167                 area = css->cub_addr2;
 168                 idx = chpid.id - 128;
 169         }
 170         entry = area + (idx * sizeof(struct cmg_entry));
 171         do {
 172                 memcpy(buf, entry, sizeof(*entry));
 173                 memcpy(&reference_buf, entry, sizeof(*entry));
 174         } while (reference_buf.values[0] != buf->values[0]);
 175 }
 176
 177 static ssize_t chp_measurement_read(struct file *filp, struct kobject *kobj,
 178                                     struct bin_attribute *bin_attr,
 179                                     char *buf, loff_t off, size_t count)
 180 {
 181         struct channel_path *chp;
 182         struct channel_subsystem *css;
 183         struct device *device;
 184         unsigned int size;
 185
 186         device = container_of(kobj, struct device, kobj);
 187         chp = to_channelpath(device);
 188         css = to_css(chp->dev.parent);
 189
 190         size = sizeof(struct cmg_entry);
 191
 192         /* Only allow single reads. */
 193         if (off || count < size)
 194                 return 0;
 195         chp_measurement_copy_block((struct cmg_entry *)buf, css, chp->chpid);
 196         count = size;
 197         return count;
 198 }
 199
 200 static struct bin_attribute chp_measurement_attr = {
 201         .attr = {
 202                 .name = "measurement",
 203                 .mode = S_IRUSR,
 204         },
 205         .size = sizeof(struct cmg_entry),
 206         .read = chp_measurement_read,
 207 };
 208
 209 void chp_remove_cmg_attr(struct channel_path *chp)
 210 {
 211         device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
 212         device_remove_bin_file(&chp->dev, &chp_measurement_attr);
 213 }
 214
 215 int chp_add_cmg_attr(struct channel_path *chp)
 216 {
 217         int ret;
 218
 219         ret = device_create_bin_file(&chp->dev, &chp_measurement_chars_attr);
 220         if (ret)
 221                 return ret;
 222         ret = device_create_bin_file(&chp->dev, &chp_measurement_attr);
 223         if (ret)
 224                 device_remove_bin_file(&chp->dev, &chp_measurement_chars_attr);
 225         return ret;
 226 }
 227
 228 /*
 229  * Files for the channel path entries.
 230  */
 231 static ssize_t chp_status_show(struct device *dev,
 232                                struct device_attribute *attr, char *buf)
 233 {
 234         struct channel_path *chp = to_channelpath(dev);
 235         int status;
 236
 237         mutex_lock(&chp->lock);
 238         status = chp->state;
 239         mutex_unlock(&chp->lock);
 240
 241         return status ? sprintf(buf, "online\n") : sprintf(buf, "offline\n");
 242 }
 243
 244 static ssize_t chp_status_write(struct device *dev,
 245                                 struct device_attribute *attr,
 246                                 const char *buf, size_t count)
 247 {
 248         struct channel_path *cp = to_channelpath(dev);
 249         char cmd[10];
 250         int num_args;
 251         int error;
 252
 253         num_args = sscanf(buf, "%5s", cmd);
 254         if (!num_args)
 255                 return count;
 256
 257         if (!strncasecmp(cmd, "on", 2) || !strcmp(cmd, "1")) {
 258                 mutex_lock(&cp->lock);
 259                 error = s390_vary_chpid(cp->chpid, 1);
 260                 mutex_unlock(&cp->lock);
 261         } else if (!strncasecmp(cmd, "off", 3) || !strcmp(cmd, "0")) {
 262                 mutex_lock(&cp->lock);
 263                 error = s390_vary_chpid(cp->chpid, 0);
 264                 mutex_unlock(&cp->lock);
 265         } else
 266                 error = -EINVAL;
 267
 268         return error < 0 ? error : count;
 269 }
 270
 271 static DEVICE_ATTR(status, 0644, chp_status_show, chp_status_write);
 272
 273 static ssize_t chp_configure_show(struct device *dev,
 274                                   struct device_attribute *attr, char *buf)
 275 {
 276         struct channel_path *cp;
 277         int status;
 278
 279         cp = to_channelpath(dev);
 280         status = chp_info_get_status(cp->chpid);
 281         if (status < 0)
 282                 return status;
 283
 284         return snprintf(buf, PAGE_SIZE, "%d\n", status);
 285 }
 286
 287 static int cfg_wait_idle(void);
 288
 289 static ssize_t chp_configure_write(struct device *dev,
 290                                    struct device_attribute *attr,
 291                                    const char *buf, size_t count)
 292 {
 293         struct channel_path *cp;
 294         int val;
 295         char delim;
 296
 297         if (sscanf(buf, "%d %c", &val, &delim) != 1)
 298                 return -EINVAL;
 299         if (val != 0 && val != 1)
 300                 return -EINVAL;
 301         cp = to_channelpath(dev);
 302         chp_cfg_schedule(cp->chpid, val);
 303         cfg_wait_idle();
 304
 305         return count;
 306 }
 307
 308 static DEVICE_ATTR(configure, 0644, chp_configure_show, chp_configure_write);
 309
 310 static ssize_t chp_type_show(struct device *dev, struct device_attribute *attr,
 311                              char *buf)
 312 {
 313         struct channel_path *chp = to_channelpath(dev);
 314         u8 type;
 315
 316         mutex_lock(&chp->lock);
 317         type = chp->desc.desc;
 318         mutex_unlock(&chp->lock);
 319         return sprintf(buf, "%x\n", type);
 320 }
 321
 322 static DEVICE_ATTR(type, 0444, chp_type_show, NULL);
 323
 324 static ssize_t chp_cmg_show(struct device *dev, struct device_attribute *attr,
 325                             char *buf)
 326 {
 327         struct channel_path *chp = to_channelpath(dev);
 328
 329         if (!chp)
 330                 return 0;
 331         if (chp->cmg == -1) /* channel measurements not available */
 332                 return sprintf(buf, "unknown\n");
 333         return sprintf(buf, "%x\n", chp->cmg);
 334 }
 335
 336 static DEVICE_ATTR(cmg, 0444, chp_cmg_show, NULL);
 337
 338 static ssize_t chp_shared_show(struct device *dev,
 339                                struct device_attribute *attr, char *buf)
 340 {
 341         struct channel_path *chp = to_channelpath(dev);
 342
 343         if (!chp)
 344                 return 0;
 345         if (chp->shared == -1) /* channel measurements not available */
 346                 return sprintf(buf, "unknown\n");
 347         return sprintf(buf, "%x\n", chp->shared);
 348 }
 349
 350 static DEVICE_ATTR(shared, 0444, chp_shared_show, NULL);
 351
 352 static ssize_t chp_chid_show(struct device *dev, struct device_attribute *attr,
 353                              char *buf)
 354 {
 355         struct channel_path *chp = to_channelpath(dev);
 356         ssize_t rc;
 357
 358         mutex_lock(&chp->lock);
 359         if (chp->desc_fmt1.flags & 0x10)
 360                 rc = sprintf(buf, "%04x\n", chp->desc_fmt1.chid);
 361         else
 362                 rc = 0;
 363         mutex_unlock(&chp->lock);
 364
 365         return rc;
 366 }
 367 static DEVICE_ATTR(chid, 0444, chp_chid_show, NULL);
 368
 369 static ssize_t chp_chid_external_show(struct device *dev,
 370                                       struct device_attribute *attr, char *buf)
 371 {
 372         struct channel_path *chp = to_channelpath(dev);
 373         ssize_t rc;
 374
 375         mutex_lock(&chp->lock);
 376         if (chp->desc_fmt1.flags & 0x10)
 377                 rc = sprintf(buf, "%x\n", chp->desc_fmt1.flags & 0x8 ? 1 : 0);
 378         else
 379                 rc = 0;
 380         mutex_unlock(&chp->lock);
 381
 382         return rc;
 383 }
 384 static DEVICE_ATTR(chid_external, 0444, chp_chid_external_show, NULL);
 385
 386 static struct attribute *chp_attrs[] = {
 387         &dev_attr_status.attr,
 388         &dev_attr_configure.attr,
 389         &dev_attr_type.attr,
 390         &dev_attr_cmg.attr,
 391         &dev_attr_shared.attr,
 392         &dev_attr_chid.attr,
 393         &dev_attr_chid_external.attr,
 394         NULL,
 395 };
 396 static struct attribute_group chp_attr_group = {
 397         .attrs = chp_attrs,
 398 };
 399 static const struct attribute_group *chp_attr_groups[] = {
 400         &chp_attr_group,
 401         NULL,
 402 };
 403
 404 static void chp_release(struct device *dev)
 405 {
 406         struct channel_path *cp;
 407
 408         cp = to_channelpath(dev);
 409         kfree(cp);
 410 }
 411
 412 /**
 413  * chp_update_desc - update channel-path description
 414  * @chp - channel-path
 415  *
 416  * Update the channel-path description of the specified channel-path
 417  * including channel measurement related information.
 418  * Return zero on success, non-zero otherwise.
 419  */
 420 int chp_update_desc(struct channel_path *chp)
 421 {
 422         int rc;
 423
 424         rc = chsc_determine_base_channel_path_desc(chp->chpid, &chp->desc);
 425         if (rc)
 426                 return rc;
 427
 428         /*
 429          * Fetching the following data is optional. Not all machines or
 430          * hypervisors implement the required chsc commands.
 431          */
 432         chsc_determine_fmt1_channel_path_desc(chp->chpid, &chp->desc_fmt1);
 433         chsc_get_channel_measurement_chars(chp);
 434
 435         return 0;
 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 /* Fetch the first configure task. Set chpid accordingly. */
 669 static enum cfg_task_t chp_cfg_fetch_task(struct chp_id *chpid)
 670 {
 671         enum cfg_task_t t = cfg_none;
 672
 673         chp_id_for_each(chpid) {
 674                 t = cfg_get_task(*chpid);
 675                 if (t != cfg_none)
 676                         break;
 677         }
 678
 679         return t;
 680 }
 681
 682 /* Perform one configure/deconfigure request. Reschedule work function until
 683  * last request. */
 684 static void cfg_func(struct work_struct *work)
 685 {
 686         struct chp_id chpid;
 687         enum cfg_task_t t;
 688         int rc;
 689
 690         spin_lock(&cfg_lock);
 691         t = chp_cfg_fetch_task(&chpid);
 692         spin_unlock(&cfg_lock);
 693
 694         switch (t) {
 695         case cfg_configure:
 696                 rc = sclp_chp_configure(chpid);
 697                 if (rc)
 698                         CIO_MSG_EVENT(2, "chp: sclp_chp_configure(%x.%02x)="
 699                                       "%d\n", chpid.cssid, chpid.id, rc);
 700                 else {
 701                         info_expire();
 702                         chsc_chp_online(chpid);
 703                 }
 704                 break;
 705         case cfg_deconfigure:
 706                 rc = sclp_chp_deconfigure(chpid);
 707                 if (rc)
 708                         CIO_MSG_EVENT(2, "chp: sclp_chp_deconfigure(%x.%02x)="
 709                                       "%d\n", chpid.cssid, chpid.id, rc);
 710                 else {
 711                         info_expire();
 712                         chsc_chp_offline(chpid);
 713                 }
 714                 break;
 715         case cfg_none:
 716                 /* Get updated information after last change. */
 717                 info_update();
 718                 wake_up_interruptible(&cfg_wait_queue);
 719                 return;
 720         }
 721         spin_lock(&cfg_lock);
 722         if (t == cfg_get_task(chpid))
 723                 cfg_set_task(chpid, cfg_none);
 724         spin_unlock(&cfg_lock);
 725         schedule_work(&cfg_work);
 726 }
 727
 728 /**
 729  * chp_cfg_schedule - schedule chpid configuration request
 730  * @chpid - channel-path ID
 731  * @configure - Non-zero for configure, zero for deconfigure
 732  *
 733  * Schedule a channel-path configuration/deconfiguration request.
 734  */
 735 void chp_cfg_schedule(struct chp_id chpid, int configure)
 736 {
 737         CIO_MSG_EVENT(2, "chp_cfg_sched%x.%02x=%d\n", chpid.cssid, chpid.id,
 738                       configure);
 739         spin_lock(&cfg_lock);
 740         cfg_set_task(chpid, configure ? cfg_configure : cfg_deconfigure);
 741         spin_unlock(&cfg_lock);
 742         schedule_work(&cfg_work);
 743 }
 744
 745 /**
 746  * chp_cfg_cancel_deconfigure - cancel chpid deconfiguration request
 747  * @chpid - channel-path ID
 748  *
 749  * Cancel an active channel-path deconfiguration request if it has not yet
 750  * been performed.
 751  */
 752 void chp_cfg_cancel_deconfigure(struct chp_id chpid)
 753 {
 754         CIO_MSG_EVENT(2, "chp_cfg_cancel:%x.%02x\n", chpid.cssid, chpid.id);
 755         spin_lock(&cfg_lock);
 756         if (cfg_get_task(chpid) == cfg_deconfigure)
 757                 cfg_set_task(chpid, cfg_none);
 758         spin_unlock(&cfg_lock);
 759 }
 760
 761 static bool cfg_idle(void)
 762 {
 763         struct chp_id chpid;
 764         enum cfg_task_t t;
 765
 766         spin_lock(&cfg_lock);
 767         t = chp_cfg_fetch_task(&chpid);
 768         spin_unlock(&cfg_lock);
 769
 770         return t == cfg_none;
 771 }
 772
 773 static int cfg_wait_idle(void)
 774 {
 775         if (wait_event_interruptible(cfg_wait_queue, cfg_idle()))
 776                 return -ERESTARTSYS;
 777         return 0;
 778 }
 779
 780 static int __init chp_init(void)
 781 {
 782         struct chp_id chpid;
 783         int ret;
 784
 785         ret = crw_register_handler(CRW_RSC_CPATH, chp_process_crw);
 786         if (ret)
 787                 return ret;
 788         INIT_WORK(&cfg_work, cfg_func);
 789         init_waitqueue_head(&cfg_wait_queue);
 790         if (info_update())
 791                 return 0;
 792         /* Register available channel-paths. */
 793         chp_id_for_each(&chpid) {
 794                 if (chp_info_get_status(chpid) != CHP_STATUS_NOT_RECOGNIZED)
 795                         chp_new(chpid);
 796         }
 797
 798         return 0;
 799 }
 800
 801 subsys_initcall(chp_init);