drivers/s390/cio/device.c

   1 /*
   2  *  drivers/s390/cio/device.c
   3  *  bus driver for ccw devices
   4  *
   5  *    Copyright IBM Corp. 2002,2008
   6  *    Author(s): Arnd Bergmann (arndb@de.ibm.com)
   7  *               Cornelia Huck (cornelia.huck@de.ibm.com)
   8  *               Martin Schwidefsky (schwidefsky@de.ibm.com)
   9  */
  10
  11 #define KMSG_COMPONENT "cio"
  12 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  13
  14 #include <linux/module.h>
  15 #include <linux/init.h>
  16 #include <linux/spinlock.h>
  17 #include <linux/errno.h>
  18 #include <linux/err.h>
  19 #include <linux/slab.h>
  20 #include <linux/list.h>
  21 #include <linux/device.h>
  22 #include <linux/workqueue.h>
  23 #include <linux/timer.h>
  24
  25 #include <asm/ccwdev.h>
  26 #include <asm/cio.h>
  27 #include <asm/param.h>          /* HZ */
  28 #include <asm/cmb.h>
  29 #include <asm/isc.h>
  30
  31 #include "chp.h"
  32 #include "cio.h"
  33 #include "cio_debug.h"
  34 #include "css.h"
  35 #include "device.h"
  36 #include "ioasm.h"
  37 #include "io_sch.h"
  38 #include "blacklist.h"
  39 #include "chsc.h"
  40
  41 static struct timer_list recovery_timer;
  42 static DEFINE_SPINLOCK(recovery_lock);
  43 static int recovery_phase;
  44 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  45
  46 /******************* bus type handling ***********************/
  47
  48 /* The Linux driver model distinguishes between a bus type and
  49  * the bus itself. Of course we only have one channel
  50  * subsystem driver and one channel system per machine, but
  51  * we still use the abstraction. T.R. says it's a good idea. */
  52 static int
  53 ccw_bus_match (struct device * dev, struct device_driver * drv)
  54 {
  55         struct ccw_device *cdev = to_ccwdev(dev);
  56         struct ccw_driver *cdrv = to_ccwdrv(drv);
  57         const struct ccw_device_id *ids = cdrv->ids, *found;
  58
  59         if (!ids)
  60                 return 0;
  61
  62         found = ccw_device_id_match(ids, &cdev->id);
  63         if (!found)
  64                 return 0;
  65
  66         cdev->id.driver_info = found->driver_info;
  67
  68         return 1;
  69 }
  70
  71 /* Store modalias string delimited by prefix/suffix string into buffer with
  72  * specified size. Return length of resulting string (excluding trailing '\0')
  73  * even if string doesn't fit buffer (snprintf semantics). */
  74 static int snprint_alias(char *buf, size_t size,
  75                          struct ccw_device_id *id, const char *suffix)
  76 {
  77         int len;
  78
  79         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  80         if (len > size)
  81                 return len;
  82         buf += len;
  83         size -= len;
  84
  85         if (id->dev_type != 0)
  86                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  87                                 id->dev_model, suffix);
  88         else
  89                 len += snprintf(buf, size, "dtdm%s", suffix);
  90
  91         return len;
  92 }
  93
  94 /* Set up environment variables for ccw device uevent. Return 0 on success,
  95  * non-zero otherwise. */
  96 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  97 {
  98         struct ccw_device *cdev = to_ccwdev(dev);
  99         struct ccw_device_id *id = &(cdev->id);
 100         int ret;
 101         char modalias_buf[30];
 102
 103         /* CU_TYPE= */
 104         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
 105         if (ret)
 106                 return ret;
 107
 108         /* CU_MODEL= */
 109         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 110         if (ret)
 111                 return ret;
 112
 113         /* The next two can be zero, that's ok for us */
 114         /* DEV_TYPE= */
 115         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 116         if (ret)
 117                 return ret;
 118
 119         /* DEV_MODEL= */
 120         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 121         if (ret)
 122                 return ret;
 123
 124         /* MODALIAS=  */
 125         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 126         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 127         return ret;
 128 }
 129
 130 static struct bus_type ccw_bus_type;
 131
 132 static void io_subchannel_irq(struct subchannel *);
 133 static int io_subchannel_probe(struct subchannel *);
 134 static int io_subchannel_remove(struct subchannel *);
 135 static void io_subchannel_shutdown(struct subchannel *);
 136 static int io_subchannel_sch_event(struct subchannel *, int);
 137 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
 138                                    int);
 139 static void recovery_func(unsigned long data);
 140 wait_queue_head_t ccw_device_init_wq;
 141 atomic_t ccw_device_init_count;
 142
 143 static struct css_device_id io_subchannel_ids[] = {
 144         { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
 145         { /* end of list */ },
 146 };
 147 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
 148
 149 static int io_subchannel_prepare(struct subchannel *sch)
 150 {
 151         struct ccw_device *cdev;
 152         /*
 153          * Don't allow suspend while a ccw device registration
 154          * is still outstanding.
 155          */
 156         cdev = sch_get_cdev(sch);
 157         if (cdev && !device_is_registered(&cdev->dev))
 158                 return -EAGAIN;
 159         return 0;
 160 }
 161
 162 static int io_subchannel_settle(void)
 163 {
 164         int ret;
 165
 166         ret = wait_event_interruptible(ccw_device_init_wq,
 167                                 atomic_read(&ccw_device_init_count) == 0);
 168         if (ret)
 169                 return -EINTR;
 170         flush_workqueue(cio_work_q);
 171         return 0;
 172 }
 173
 174 static struct css_driver io_subchannel_driver = {
 175         .drv = {
 176                 .owner = THIS_MODULE,
 177                 .name = "io_subchannel",
 178         },
 179         .subchannel_type = io_subchannel_ids,
 180         .irq = io_subchannel_irq,
 181         .sch_event = io_subchannel_sch_event,
 182         .chp_event = io_subchannel_chp_event,
 183         .probe = io_subchannel_probe,
 184         .remove = io_subchannel_remove,
 185         .shutdown = io_subchannel_shutdown,
 186         .prepare = io_subchannel_prepare,
 187         .settle = io_subchannel_settle,
 188 };
 189
 190 int __init io_subchannel_init(void)
 191 {
 192         int ret;
 193
 194         init_waitqueue_head(&ccw_device_init_wq);
 195         atomic_set(&ccw_device_init_count, 0);
 196         setup_timer(&recovery_timer, recovery_func, 0);
 197
 198         ret = bus_register(&ccw_bus_type);
 199         if (ret)
 200                 return ret;
 201         ret = css_driver_register(&io_subchannel_driver);
 202         if (ret)
 203                 bus_unregister(&ccw_bus_type);
 204
 205         return ret;
 206 }
 207
 208
 209 /************************ device handling **************************/
 210
 211 /*
 212  * A ccw_device has some interfaces in sysfs in addition to the
 213  * standard ones.
 214  * The following entries are designed to export the information which
 215  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 216  * are obvious, so they don't have an entry :)
 217  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 218  */
 219 static ssize_t
 220 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 221 {
 222         struct subchannel *sch = to_subchannel(dev);
 223         struct chsc_ssd_info *ssd = &sch->ssd_info;
 224         ssize_t ret = 0;
 225         int chp;
 226         int mask;
 227
 228         for (chp = 0; chp < 8; chp++) {
 229                 mask = 0x80 >> chp;
 230                 if (ssd->path_mask & mask)
 231                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 232                 else
 233                         ret += sprintf(buf + ret, "00 ");
 234         }
 235         ret += sprintf (buf+ret, "\n");
 236         return min((ssize_t)PAGE_SIZE, ret);
 237 }
 238
 239 static ssize_t
 240 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 241 {
 242         struct subchannel *sch = to_subchannel(dev);
 243         struct pmcw *pmcw = &sch->schib.pmcw;
 244
 245         return sprintf (buf, "%02x %02x %02x\n",
 246                         pmcw->pim, pmcw->pam, pmcw->pom);
 247 }
 248
 249 static ssize_t
 250 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 251 {
 252         struct ccw_device *cdev = to_ccwdev(dev);
 253         struct ccw_device_id *id = &(cdev->id);
 254
 255         if (id->dev_type != 0)
 256                 return sprintf(buf, "%04x/%02x\n",
 257                                 id->dev_type, id->dev_model);
 258         else
 259                 return sprintf(buf, "n/a\n");
 260 }
 261
 262 static ssize_t
 263 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 264 {
 265         struct ccw_device *cdev = to_ccwdev(dev);
 266         struct ccw_device_id *id = &(cdev->id);
 267
 268         return sprintf(buf, "%04x/%02x\n",
 269                        id->cu_type, id->cu_model);
 270 }
 271
 272 static ssize_t
 273 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 274 {
 275         struct ccw_device *cdev = to_ccwdev(dev);
 276         struct ccw_device_id *id = &(cdev->id);
 277         int len;
 278
 279         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 280
 281         return len > PAGE_SIZE ? PAGE_SIZE : len;
 282 }
 283
 284 static ssize_t
 285 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 286 {
 287         struct ccw_device *cdev = to_ccwdev(dev);
 288
 289         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 290 }
 291
 292 int ccw_device_is_orphan(struct ccw_device *cdev)
 293 {
 294         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 295 }
 296
 297 static void ccw_device_unregister(struct ccw_device *cdev)
 298 {
 299         if (device_is_registered(&cdev->dev)) {
 300                 /* Undo device_add(). */
 301                 device_del(&cdev->dev);
 302         }
 303         if (cdev->private->flags.initialized) {
 304                 cdev->private->flags.initialized = 0;
 305                 /* Release reference from device_initialize(). */
 306                 put_device(&cdev->dev);
 307         }
 308 }
 309
 310 static void io_subchannel_quiesce(struct subchannel *);
 311
 312 /**
 313  * ccw_device_set_offline() - disable a ccw device for I/O
 314  * @cdev: target ccw device
 315  *
 316  * This function calls the driver's set_offline() function for @cdev, if
 317  * given, and then disables @cdev.
 318  * Returns:
 319  *   %0 on success and a negative error value on failure.
 320  * Context:
 321  *  enabled, ccw device lock not held
 322  */
 323 int ccw_device_set_offline(struct ccw_device *cdev)
 324 {
 325         struct subchannel *sch;
 326         int ret, state;
 327
 328         if (!cdev)
 329                 return -ENODEV;
 330         if (!cdev->online || !cdev->drv)
 331                 return -EINVAL;
 332
 333         if (cdev->drv->set_offline) {
 334                 ret = cdev->drv->set_offline(cdev);
 335                 if (ret != 0)
 336                         return ret;
 337         }
 338         cdev->online = 0;
 339         spin_lock_irq(cdev->ccwlock);
 340         sch = to_subchannel(cdev->dev.parent);
 341         /* Wait until a final state or DISCONNECTED is reached */
 342         while (!dev_fsm_final_state(cdev) &&
 343                cdev->private->state != DEV_STATE_DISCONNECTED) {
 344                 spin_unlock_irq(cdev->ccwlock);
 345                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 346                            cdev->private->state == DEV_STATE_DISCONNECTED));
 347                 spin_lock_irq(cdev->ccwlock);
 348         }
 349         do {
 350                 ret = ccw_device_offline(cdev);
 351                 if (!ret)
 352                         break;
 353                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device "
 354                               "0.%x.%04x\n", ret, cdev->private->dev_id.ssid,
 355                               cdev->private->dev_id.devno);
 356                 if (ret != -EBUSY)
 357                         goto error;
 358                 state = cdev->private->state;
 359                 spin_unlock_irq(cdev->ccwlock);
 360                 io_subchannel_quiesce(sch);
 361                 spin_lock_irq(cdev->ccwlock);
 362                 cdev->private->state = state;
 363         } while (ret == -EBUSY);
 364         spin_unlock_irq(cdev->ccwlock);
 365         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 366                    cdev->private->state == DEV_STATE_DISCONNECTED));
 367         /* Inform the user if set offline failed. */
 368         if (cdev->private->state == DEV_STATE_BOXED) {
 369                 pr_warning("%s: The device entered boxed state while "
 370                            "being set offline\n", dev_name(&cdev->dev));
 371         } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 372                 pr_warning("%s: The device stopped operating while "
 373                            "being set offline\n", dev_name(&cdev->dev));
 374         }
 375         /* Give up reference from ccw_device_set_online(). */
 376         put_device(&cdev->dev);
 377         return 0;
 378
 379 error:
 380         cdev->private->state = DEV_STATE_OFFLINE;
 381         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 382         spin_unlock_irq(cdev->ccwlock);
 383         /* Give up reference from ccw_device_set_online(). */
 384         put_device(&cdev->dev);
 385         return -ENODEV;
 386 }
 387
 388 /**
 389  * ccw_device_set_online() - enable a ccw device for I/O
 390  * @cdev: target ccw device
 391  *
 392  * This function first enables @cdev and then calls the driver's set_online()
 393  * function for @cdev, if given. If set_online() returns an error, @cdev is
 394  * disabled again.
 395  * Returns:
 396  *   %0 on success and a negative error value on failure.
 397  * Context:
 398  *  enabled, ccw device lock not held
 399  */
 400 int ccw_device_set_online(struct ccw_device *cdev)
 401 {
 402         int ret;
 403         int ret2;
 404
 405         if (!cdev)
 406                 return -ENODEV;
 407         if (cdev->online || !cdev->drv)
 408                 return -EINVAL;
 409         /* Hold on to an extra reference while device is online. */
 410         if (!get_device(&cdev->dev))
 411                 return -ENODEV;
 412
 413         spin_lock_irq(cdev->ccwlock);
 414         ret = ccw_device_online(cdev);
 415         spin_unlock_irq(cdev->ccwlock);
 416         if (ret == 0)
 417                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 418         else {
 419                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
 420                               "device 0.%x.%04x\n",
 421                               ret, cdev->private->dev_id.ssid,
 422                               cdev->private->dev_id.devno);
 423                 /* Give up online reference since onlining failed. */
 424                 put_device(&cdev->dev);
 425                 return ret;
 426         }
 427         spin_lock_irq(cdev->ccwlock);
 428         /* Check if online processing was successful */
 429         if ((cdev->private->state != DEV_STATE_ONLINE) &&
 430             (cdev->private->state != DEV_STATE_W4SENSE)) {
 431                 spin_unlock_irq(cdev->ccwlock);
 432                 /* Inform the user that set online failed. */
 433                 if (cdev->private->state == DEV_STATE_BOXED) {
 434                         pr_warning("%s: Setting the device online failed "
 435                                    "because it is boxed\n",
 436                                    dev_name(&cdev->dev));
 437                 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 438                         pr_warning("%s: Setting the device online failed "
 439                                    "because it is not operational\n",
 440                                    dev_name(&cdev->dev));
 441                 }
 442                 /* Give up online reference since onlining failed. */
 443                 put_device(&cdev->dev);
 444                 return -ENODEV;
 445         }
 446         spin_unlock_irq(cdev->ccwlock);
 447         if (cdev->drv->set_online)
 448                 ret = cdev->drv->set_online(cdev);
 449         if (ret)
 450                 goto rollback;
 451         cdev->online = 1;
 452         return 0;
 453
 454 rollback:
 455         spin_lock_irq(cdev->ccwlock);
 456         /* Wait until a final state or DISCONNECTED is reached */
 457         while (!dev_fsm_final_state(cdev) &&
 458                cdev->private->state != DEV_STATE_DISCONNECTED) {
 459                 spin_unlock_irq(cdev->ccwlock);
 460                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 461                            cdev->private->state == DEV_STATE_DISCONNECTED));
 462                 spin_lock_irq(cdev->ccwlock);
 463         }
 464         ret2 = ccw_device_offline(cdev);
 465         if (ret2)
 466                 goto error;
 467         spin_unlock_irq(cdev->ccwlock);
 468         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 469                    cdev->private->state == DEV_STATE_DISCONNECTED));
 470         /* Give up online reference since onlining failed. */
 471         put_device(&cdev->dev);
 472         return ret;
 473
 474 error:
 475         CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
 476                       "device 0.%x.%04x\n",
 477                       ret2, cdev->private->dev_id.ssid,
 478                       cdev->private->dev_id.devno);
 479         cdev->private->state = DEV_STATE_OFFLINE;
 480         spin_unlock_irq(cdev->ccwlock);
 481         /* Give up online reference since onlining failed. */
 482         put_device(&cdev->dev);
 483         return ret;
 484 }
 485
 486 static int online_store_handle_offline(struct ccw_device *cdev)
 487 {
 488         if (cdev->private->state == DEV_STATE_DISCONNECTED) {
 489                 spin_lock_irq(cdev->ccwlock);
 490                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
 491                 spin_unlock_irq(cdev->ccwlock);
 492                 return 0;
 493         }
 494         if (cdev->drv && cdev->drv->set_offline)
 495                 return ccw_device_set_offline(cdev);
 496         return -EINVAL;
 497 }
 498
 499 static int online_store_recog_and_online(struct ccw_device *cdev)
 500 {
 501         /* Do device recognition, if needed. */
 502         if (cdev->private->state == DEV_STATE_BOXED) {
 503                 spin_lock_irq(cdev->ccwlock);
 504                 ccw_device_recognition(cdev);
 505                 spin_unlock_irq(cdev->ccwlock);
 506                 wait_event(cdev->private->wait_q,
 507                            cdev->private->flags.recog_done);
 508                 if (cdev->private->state != DEV_STATE_OFFLINE)
 509                         /* recognition failed */
 510                         return -EAGAIN;
 511         }
 512         if (cdev->drv && cdev->drv->set_online)
 513                 return ccw_device_set_online(cdev);
 514         return -EINVAL;
 515 }
 516
 517 static int online_store_handle_online(struct ccw_device *cdev, int force)
 518 {
 519         int ret;
 520
 521         ret = online_store_recog_and_online(cdev);
 522         if (ret && !force)
 523                 return ret;
 524         if (force && cdev->private->state == DEV_STATE_BOXED) {
 525                 ret = ccw_device_stlck(cdev);
 526                 if (ret)
 527                         return ret;
 528                 if (cdev->id.cu_type == 0)
 529                         cdev->private->state = DEV_STATE_NOT_OPER;
 530                 ret = online_store_recog_and_online(cdev);
 531                 if (ret)
 532                         return ret;
 533         }
 534         return 0;
 535 }
 536
 537 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 538                              const char *buf, size_t count)
 539 {
 540         struct ccw_device *cdev = to_ccwdev(dev);
 541         int force, ret;
 542         unsigned long i;
 543
 544         /* Prevent conflict between multiple on-/offline processing requests. */
 545         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 546                 return -EAGAIN;
 547         /* Prevent conflict between internal I/Os and on-/offline processing. */
 548         if (!dev_fsm_final_state(cdev) &&
 549             cdev->private->state != DEV_STATE_DISCONNECTED) {
 550                 ret = -EAGAIN;
 551                 goto out_onoff;
 552         }
 553         /* Prevent conflict between pending work and on-/offline processing.*/
 554         if (work_pending(&cdev->private->todo_work)) {
 555                 ret = -EAGAIN;
 556                 goto out_onoff;
 557         }
 558
 559         if (cdev->drv && !try_module_get(cdev->drv->driver.owner)) {
 560                 ret = -EINVAL;
 561                 goto out_onoff;
 562         }
 563         if (!strncmp(buf, "force\n", count)) {
 564                 force = 1;
 565                 i = 1;
 566                 ret = 0;
 567         } else {
 568                 force = 0;
 569                 ret = strict_strtoul(buf, 16, &i);
 570         }
 571         if (ret)
 572                 goto out;
 573         switch (i) {
 574         case 0:
 575                 ret = online_store_handle_offline(cdev);
 576                 break;
 577         case 1:
 578                 ret = online_store_handle_online(cdev, force);
 579                 break;
 580         default:
 581                 ret = -EINVAL;
 582         }
 583 out:
 584         if (cdev->drv)
 585                 module_put(cdev->drv->driver.owner);
 586 out_onoff:
 587         atomic_set(&cdev->private->onoff, 0);
 588         return (ret < 0) ? ret : count;
 589 }
 590
 591 static ssize_t
 592 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 593 {
 594         struct ccw_device *cdev = to_ccwdev(dev);
 595         struct subchannel *sch;
 596
 597         if (ccw_device_is_orphan(cdev))
 598                 return sprintf(buf, "no device\n");
 599         switch (cdev->private->state) {
 600         case DEV_STATE_BOXED:
 601                 return sprintf(buf, "boxed\n");
 602         case DEV_STATE_DISCONNECTED:
 603         case DEV_STATE_DISCONNECTED_SENSE_ID:
 604         case DEV_STATE_NOT_OPER:
 605                 sch = to_subchannel(dev->parent);
 606                 if (!sch->lpm)
 607                         return sprintf(buf, "no path\n");
 608                 else
 609                         return sprintf(buf, "no device\n");
 610         default:
 611                 /* All other states considered fine. */
 612                 return sprintf(buf, "good\n");
 613         }
 614 }
 615
 616 static ssize_t
 617 initiate_logging(struct device *dev, struct device_attribute *attr,
 618                  const char *buf, size_t count)
 619 {
 620         struct subchannel *sch = to_subchannel(dev);
 621         int rc;
 622
 623         rc = chsc_siosl(sch->schid);
 624         if (rc < 0) {
 625                 pr_warning("Logging for subchannel 0.%x.%04x failed with "
 626                            "errno=%d\n",
 627                            sch->schid.ssid, sch->schid.sch_no, rc);
 628                 return rc;
 629         }
 630         pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
 631                   sch->schid.ssid, sch->schid.sch_no);
 632         return count;
 633 }
 634
 635 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 636 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 637 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 638 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 639 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 640 static DEVICE_ATTR(online, 0644, online_show, online_store);
 641 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 642 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
 643
 644 static struct attribute *io_subchannel_attrs[] = {
 645         &dev_attr_chpids.attr,
 646         &dev_attr_pimpampom.attr,
 647         &dev_attr_logging.attr,
 648         NULL,
 649 };
 650
 651 static struct attribute_group io_subchannel_attr_group = {
 652         .attrs = io_subchannel_attrs,
 653 };
 654
 655 static struct attribute * ccwdev_attrs[] = {
 656         &dev_attr_devtype.attr,
 657         &dev_attr_cutype.attr,
 658         &dev_attr_modalias.attr,
 659         &dev_attr_online.attr,
 660         &dev_attr_cmb_enable.attr,
 661         &dev_attr_availability.attr,
 662         NULL,
 663 };
 664
 665 static struct attribute_group ccwdev_attr_group = {
 666         .attrs = ccwdev_attrs,
 667 };
 668
 669 static const struct attribute_group *ccwdev_attr_groups[] = {
 670         &ccwdev_attr_group,
 671         NULL,
 672 };
 673
 674 /* this is a simple abstraction for device_register that sets the
 675  * correct bus type and adds the bus specific files */
 676 static int ccw_device_register(struct ccw_device *cdev)
 677 {
 678         struct device *dev = &cdev->dev;
 679         int ret;
 680
 681         dev->bus = &ccw_bus_type;
 682         ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
 683                            cdev->private->dev_id.devno);
 684         if (ret)
 685                 return ret;
 686         return device_add(dev);
 687 }
 688
 689 static int match_dev_id(struct device *dev, void *data)
 690 {
 691         struct ccw_device *cdev = to_ccwdev(dev);
 692         struct ccw_dev_id *dev_id = data;
 693
 694         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 695 }
 696
 697 static struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
 698 {
 699         struct device *dev;
 700
 701         dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
 702
 703         return dev ? to_ccwdev(dev) : NULL;
 704 }
 705
 706 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
 707 {
 708         int ret;
 709
 710         if (device_is_registered(&cdev->dev)) {
 711                 device_release_driver(&cdev->dev);
 712                 ret = device_attach(&cdev->dev);
 713                 WARN_ON(ret == -ENODEV);
 714         }
 715 }
 716
 717 static void
 718 ccw_device_release(struct device *dev)
 719 {
 720         struct ccw_device *cdev;
 721
 722         cdev = to_ccwdev(dev);
 723         /* Release reference of parent subchannel. */
 724         put_device(cdev->dev.parent);
 725         kfree(cdev->private);
 726         kfree(cdev);
 727 }
 728
 729 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 730 {
 731         struct ccw_device *cdev;
 732
 733         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 734         if (cdev) {
 735                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 736                                         GFP_KERNEL | GFP_DMA);
 737                 if (cdev->private)
 738                         return cdev;
 739         }
 740         kfree(cdev);
 741         return ERR_PTR(-ENOMEM);
 742 }
 743
 744 static void ccw_device_todo(struct work_struct *work);
 745
 746 static int io_subchannel_initialize_dev(struct subchannel *sch,
 747                                         struct ccw_device *cdev)
 748 {
 749         cdev->private->cdev = cdev;
 750         atomic_set(&cdev->private->onoff, 0);
 751         cdev->dev.parent = &sch->dev;
 752         cdev->dev.release = ccw_device_release;
 753         INIT_WORK(&cdev->private->todo_work, ccw_device_todo);
 754         cdev->dev.groups = ccwdev_attr_groups;
 755         /* Do first half of device_register. */
 756         device_initialize(&cdev->dev);
 757         if (!get_device(&sch->dev)) {
 758                 /* Release reference from device_initialize(). */
 759                 put_device(&cdev->dev);
 760                 return -ENODEV;
 761         }
 762         cdev->private->flags.initialized = 1;
 763         return 0;
 764 }
 765
 766 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 767 {
 768         struct ccw_device *cdev;
 769         int ret;
 770
 771         cdev = io_subchannel_allocate_dev(sch);
 772         if (!IS_ERR(cdev)) {
 773                 ret = io_subchannel_initialize_dev(sch, cdev);
 774                 if (ret)
 775                         cdev = ERR_PTR(ret);
 776         }
 777         return cdev;
 778 }
 779
 780 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
 781
 782 static void sch_create_and_recog_new_device(struct subchannel *sch)
 783 {
 784         struct ccw_device *cdev;
 785
 786         /* Need to allocate a new ccw device. */
 787         cdev = io_subchannel_create_ccwdev(sch);
 788         if (IS_ERR(cdev)) {
 789                 /* OK, we did everything we could... */
 790                 css_sch_device_unregister(sch);
 791                 return;
 792         }
 793         /* Start recognition for the new ccw device. */
 794         io_subchannel_recog(cdev, sch);
 795 }
 796
 797 /*
 798  * Register recognized device.
 799  */
 800 static void io_subchannel_register(struct ccw_device *cdev)
 801 {
 802         struct subchannel *sch;
 803         int ret, adjust_init_count = 1;
 804         unsigned long flags;
 805
 806         sch = to_subchannel(cdev->dev.parent);
 807         /*
 808          * Check if subchannel is still registered. It may have become
 809          * unregistered if a machine check hit us after finishing
 810          * device recognition but before the register work could be
 811          * queued.
 812          */
 813         if (!device_is_registered(&sch->dev))
 814                 goto out_err;
 815         css_update_ssd_info(sch);
 816         /*
 817          * io_subchannel_register() will also be called after device
 818          * recognition has been done for a boxed device (which will already
 819          * be registered). We need to reprobe since we may now have sense id
 820          * information.
 821          */
 822         if (device_is_registered(&cdev->dev)) {
 823                 if (!cdev->drv) {
 824                         ret = device_reprobe(&cdev->dev);
 825                         if (ret)
 826                                 /* We can't do much here. */
 827                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
 828                                               " %d for 0.%x.%04x\n", ret,
 829                                               cdev->private->dev_id.ssid,
 830                                               cdev->private->dev_id.devno);
 831                 }
 832                 adjust_init_count = 0;
 833                 goto out;
 834         }
 835         /*
 836          * Now we know this subchannel will stay, we can throw
 837          * our delayed uevent.
 838          */
 839         dev_set_uevent_suppress(&sch->dev, 0);
 840         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 841         /* make it known to the system */
 842         ret = ccw_device_register(cdev);
 843         if (ret) {
 844                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 845                               cdev->private->dev_id.ssid,
 846                               cdev->private->dev_id.devno, ret);
 847                 spin_lock_irqsave(sch->lock, flags);
 848                 sch_set_cdev(sch, NULL);
 849                 spin_unlock_irqrestore(sch->lock, flags);
 850                 /* Release initial device reference. */
 851                 put_device(&cdev->dev);
 852                 goto out_err;
 853         }
 854 out:
 855         cdev->private->flags.recog_done = 1;
 856         wake_up(&cdev->private->wait_q);
 857 out_err:
 858         if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
 859                 wake_up(&ccw_device_init_wq);
 860 }
 861
 862 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
 863 {
 864         struct subchannel *sch;
 865
 866         /* Get subchannel reference for local processing. */
 867         if (!get_device(cdev->dev.parent))
 868                 return;
 869         sch = to_subchannel(cdev->dev.parent);
 870         css_sch_device_unregister(sch);
 871         /* Release subchannel reference for local processing. */
 872         put_device(&sch->dev);
 873 }
 874
 875 /*
 876  * subchannel recognition done. Called from the state machine.
 877  */
 878 void
 879 io_subchannel_recog_done(struct ccw_device *cdev)
 880 {
 881         if (css_init_done == 0) {
 882                 cdev->private->flags.recog_done = 1;
 883                 return;
 884         }
 885         switch (cdev->private->state) {
 886         case DEV_STATE_BOXED:
 887                 /* Device did not respond in time. */
 888         case DEV_STATE_NOT_OPER:
 889                 cdev->private->flags.recog_done = 1;
 890                 /* Remove device found not operational. */
 891                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 892                 if (atomic_dec_and_test(&ccw_device_init_count))
 893                         wake_up(&ccw_device_init_wq);
 894                 break;
 895         case DEV_STATE_OFFLINE:
 896                 /*
 897                  * We can't register the device in interrupt context so
 898                  * we schedule a work item.
 899                  */
 900                 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
 901                 break;
 902         }
 903 }
 904
 905 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 906 {
 907         struct ccw_device_private *priv;
 908
 909         cdev->ccwlock = sch->lock;
 910
 911         /* Init private data. */
 912         priv = cdev->private;
 913         priv->dev_id.devno = sch->schib.pmcw.dev;
 914         priv->dev_id.ssid = sch->schid.ssid;
 915         priv->schid = sch->schid;
 916         priv->state = DEV_STATE_NOT_OPER;
 917         INIT_LIST_HEAD(&priv->cmb_list);
 918         init_waitqueue_head(&priv->wait_q);
 919         init_timer(&priv->timer);
 920
 921         /* Increase counter of devices currently in recognition. */
 922         atomic_inc(&ccw_device_init_count);
 923
 924         /* Start async. device sensing. */
 925         spin_lock_irq(sch->lock);
 926         sch_set_cdev(sch, cdev);
 927         ccw_device_recognition(cdev);
 928         spin_unlock_irq(sch->lock);
 929 }
 930
 931 static int ccw_device_move_to_sch(struct ccw_device *cdev,
 932                                   struct subchannel *sch)
 933 {
 934         struct subchannel *old_sch;
 935         int rc, old_enabled = 0;
 936
 937         old_sch = to_subchannel(cdev->dev.parent);
 938         /* Obtain child reference for new parent. */
 939         if (!get_device(&sch->dev))
 940                 return -ENODEV;
 941
 942         if (!sch_is_pseudo_sch(old_sch)) {
 943                 spin_lock_irq(old_sch->lock);
 944                 old_enabled = old_sch->schib.pmcw.ena;
 945                 rc = 0;
 946                 if (old_enabled)
 947                         rc = cio_disable_subchannel(old_sch);
 948                 spin_unlock_irq(old_sch->lock);
 949                 if (rc == -EBUSY) {
 950                         /* Release child reference for new parent. */
 951                         put_device(&sch->dev);
 952                         return rc;
 953                 }
 954         }
 955
 956         mutex_lock(&sch->reg_mutex);
 957         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 958         mutex_unlock(&sch->reg_mutex);
 959         if (rc) {
 960                 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
 961                               cdev->private->dev_id.ssid,
 962                               cdev->private->dev_id.devno, sch->schid.ssid,
 963                               sch->schib.pmcw.dev, rc);
 964                 if (old_enabled) {
 965                         /* Try to reenable the old subchannel. */
 966                         spin_lock_irq(old_sch->lock);
 967                         cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
 968                         spin_unlock_irq(old_sch->lock);
 969                 }
 970                 /* Release child reference for new parent. */
 971                 put_device(&sch->dev);
 972                 return rc;
 973         }
 974         /* Clean up old subchannel. */
 975         if (!sch_is_pseudo_sch(old_sch)) {
 976                 spin_lock_irq(old_sch->lock);
 977                 sch_set_cdev(old_sch, NULL);
 978                 spin_unlock_irq(old_sch->lock);
 979                 css_schedule_eval(old_sch->schid);
 980         }
 981         /* Release child reference for old parent. */
 982         put_device(&old_sch->dev);
 983         /* Initialize new subchannel. */
 984         spin_lock_irq(sch->lock);
 985         cdev->private->schid = sch->schid;
 986         cdev->ccwlock = sch->lock;
 987         if (!sch_is_pseudo_sch(sch))
 988                 sch_set_cdev(sch, cdev);
 989         spin_unlock_irq(sch->lock);
 990         if (!sch_is_pseudo_sch(sch))
 991                 css_update_ssd_info(sch);
 992         return 0;
 993 }
 994
 995 static int ccw_device_move_to_orph(struct ccw_device *cdev)
 996 {
 997         struct subchannel *sch = to_subchannel(cdev->dev.parent);
 998         struct channel_subsystem *css = to_css(sch->dev.parent);
 999
1000         return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1001 }
1002
1003 static void io_subchannel_irq(struct subchannel *sch)
1004 {
1005         struct ccw_device *cdev;
1006
1007         cdev = sch_get_cdev(sch);
1008
1009         CIO_TRACE_EVENT(6, "IRQ");
1010         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1011         if (cdev)
1012                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1013 }
1014
1015 void io_subchannel_init_config(struct subchannel *sch)
1016 {
1017         memset(&sch->config, 0, sizeof(sch->config));
1018         sch->config.csense = 1;
1019 }
1020
1021 static void io_subchannel_init_fields(struct subchannel *sch)
1022 {
1023         if (cio_is_console(sch->schid))
1024                 sch->opm = 0xff;
1025         else
1026                 sch->opm = chp_get_sch_opm(sch);
1027         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1028         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1029
1030         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1031                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1032                       sch->schib.pmcw.dev, sch->schid.ssid,
1033                       sch->schid.sch_no, sch->schib.pmcw.pim,
1034                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1035
1036         io_subchannel_init_config(sch);
1037 }
1038
1039 /*
1040  * Note: We always return 0 so that we bind to the device even on error.
1041  * This is needed so that our remove function is called on unregister.
1042  */
1043 static int io_subchannel_probe(struct subchannel *sch)
1044 {
1045         struct io_subchannel_private *io_priv;
1046         struct ccw_device *cdev;
1047         int rc;
1048
1049         if (cio_is_console(sch->schid)) {
1050                 rc = sysfs_create_group(&sch->dev.kobj,
1051                                         &io_subchannel_attr_group);
1052                 if (rc)
1053                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1054                                       "attributes for subchannel "
1055                                       "0.%x.%04x (rc=%d)\n",
1056                                       sch->schid.ssid, sch->schid.sch_no, rc);
1057                 /*
1058                  * The console subchannel already has an associated ccw_device.
1059                  * Throw the delayed uevent for the subchannel, register
1060                  * the ccw_device and exit.
1061                  */
1062                 dev_set_uevent_suppress(&sch->dev, 0);
1063                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1064                 cdev = sch_get_cdev(sch);
1065                 cdev->dev.groups = ccwdev_attr_groups;
1066                 device_initialize(&cdev->dev);
1067                 cdev->private->flags.initialized = 1;
1068                 ccw_device_register(cdev);
1069                 /*
1070                  * Check if the device is already online. If it is
1071                  * the reference count needs to be corrected since we
1072                  * didn't obtain a reference in ccw_device_set_online.
1073                  */
1074                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1075                     cdev->private->state != DEV_STATE_OFFLINE &&
1076                     cdev->private->state != DEV_STATE_BOXED)
1077                         get_device(&cdev->dev);
1078                 return 0;
1079         }
1080         io_subchannel_init_fields(sch);
1081         rc = cio_commit_config(sch);
1082         if (rc)
1083                 goto out_schedule;
1084         rc = sysfs_create_group(&sch->dev.kobj,
1085                                 &io_subchannel_attr_group);
1086         if (rc)
1087                 goto out_schedule;
1088         /* Allocate I/O subchannel private data. */
1089         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1090         if (!io_priv)
1091                 goto out_schedule;
1092
1093         set_io_private(sch, io_priv);
1094         css_schedule_eval(sch->schid);
1095         return 0;
1096
1097 out_schedule:
1098         spin_lock_irq(sch->lock);
1099         css_sched_sch_todo(sch, SCH_TODO_UNREG);
1100         spin_unlock_irq(sch->lock);
1101         return 0;
1102 }
1103
1104 static int
1105 io_subchannel_remove (struct subchannel *sch)
1106 {
1107         struct io_subchannel_private *io_priv = to_io_private(sch);
1108         struct ccw_device *cdev;
1109
1110         cdev = sch_get_cdev(sch);
1111         if (!cdev)
1112                 goto out_free;
1113         io_subchannel_quiesce(sch);
1114         /* Set ccw device to not operational and drop reference. */
1115         spin_lock_irq(cdev->ccwlock);
1116         sch_set_cdev(sch, NULL);
1117         set_io_private(sch, NULL);
1118         cdev->private->state = DEV_STATE_NOT_OPER;
1119         spin_unlock_irq(cdev->ccwlock);
1120         ccw_device_unregister(cdev);
1121 out_free:
1122         kfree(io_priv);
1123         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1124         return 0;
1125 }
1126
1127 static void io_subchannel_verify(struct subchannel *sch)
1128 {
1129         struct ccw_device *cdev;
1130
1131         cdev = sch_get_cdev(sch);
1132         if (cdev)
1133                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1134 }
1135
1136 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1137 {
1138         struct ccw_device *cdev;
1139
1140         cdev = sch_get_cdev(sch);
1141         if (!cdev)
1142                 return;
1143         if (cio_update_schib(sch))
1144                 goto err;
1145         /* Check for I/O on path. */
1146         if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1147                 goto out;
1148         if (cdev->private->state == DEV_STATE_ONLINE) {
1149                 ccw_device_kill_io(cdev);
1150                 goto out;
1151         }
1152         if (cio_clear(sch))
1153                 goto err;
1154 out:
1155         /* Trigger path verification. */
1156         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1157         return;
1158
1159 err:
1160         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1161 }
1162
1163 static int io_subchannel_chp_event(struct subchannel *sch,
1164                                    struct chp_link *link, int event)
1165 {
1166         struct ccw_device *cdev = sch_get_cdev(sch);
1167         int mask;
1168
1169         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1170         if (!mask)
1171                 return 0;
1172         switch (event) {
1173         case CHP_VARY_OFF:
1174                 sch->opm &= ~mask;
1175                 sch->lpm &= ~mask;
1176                 if (cdev)
1177                         cdev->private->path_gone_mask |= mask;
1178                 io_subchannel_terminate_path(sch, mask);
1179                 break;
1180         case CHP_VARY_ON:
1181                 sch->opm |= mask;
1182                 sch->lpm |= mask;
1183                 if (cdev)
1184                         cdev->private->path_new_mask |= mask;
1185                 io_subchannel_verify(sch);
1186                 break;
1187         case CHP_OFFLINE:
1188                 if (cio_update_schib(sch))
1189                         return -ENODEV;
1190                 if (cdev)
1191                         cdev->private->path_gone_mask |= mask;
1192                 io_subchannel_terminate_path(sch, mask);
1193                 break;
1194         case CHP_ONLINE:
1195                 if (cio_update_schib(sch))
1196                         return -ENODEV;
1197                 sch->lpm |= mask & sch->opm;
1198                 if (cdev)
1199                         cdev->private->path_new_mask |= mask;
1200                 io_subchannel_verify(sch);
1201                 break;
1202         }
1203         return 0;
1204 }
1205
1206 static void io_subchannel_quiesce(struct subchannel *sch)
1207 {
1208         struct ccw_device *cdev;
1209         int ret;
1210
1211         spin_lock_irq(sch->lock);
1212         cdev = sch_get_cdev(sch);
1213         if (cio_is_console(sch->schid))
1214                 goto out_unlock;
1215         if (!sch->schib.pmcw.ena)
1216                 goto out_unlock;
1217         ret = cio_disable_subchannel(sch);
1218         if (ret != -EBUSY)
1219                 goto out_unlock;
1220         if (cdev->handler)
1221                 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1222         while (ret == -EBUSY) {
1223                 cdev->private->state = DEV_STATE_QUIESCE;
1224                 cdev->private->iretry = 255;
1225                 ret = ccw_device_cancel_halt_clear(cdev);
1226                 if (ret == -EBUSY) {
1227                         ccw_device_set_timeout(cdev, HZ/10);
1228                         spin_unlock_irq(sch->lock);
1229                         wait_event(cdev->private->wait_q,
1230                                    cdev->private->state != DEV_STATE_QUIESCE);
1231                         spin_lock_irq(sch->lock);
1232                 }
1233                 ret = cio_disable_subchannel(sch);
1234         }
1235 out_unlock:
1236         spin_unlock_irq(sch->lock);
1237 }
1238
1239 static void io_subchannel_shutdown(struct subchannel *sch)
1240 {
1241         io_subchannel_quiesce(sch);
1242 }
1243
1244 static int device_is_disconnected(struct ccw_device *cdev)
1245 {
1246         if (!cdev)
1247                 return 0;
1248         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1249                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1250 }
1251
1252 static int recovery_check(struct device *dev, void *data)
1253 {
1254         struct ccw_device *cdev = to_ccwdev(dev);
1255         int *redo = data;
1256
1257         spin_lock_irq(cdev->ccwlock);
1258         switch (cdev->private->state) {
1259         case DEV_STATE_DISCONNECTED:
1260                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1261                               cdev->private->dev_id.ssid,
1262                               cdev->private->dev_id.devno);
1263                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1264                 *redo = 1;
1265                 break;
1266         case DEV_STATE_DISCONNECTED_SENSE_ID:
1267                 *redo = 1;
1268                 break;
1269         }
1270         spin_unlock_irq(cdev->ccwlock);
1271
1272         return 0;
1273 }
1274
1275 static void recovery_work_func(struct work_struct *unused)
1276 {
1277         int redo = 0;
1278
1279         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1280         if (redo) {
1281                 spin_lock_irq(&recovery_lock);
1282                 if (!timer_pending(&recovery_timer)) {
1283                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1284                                 recovery_phase++;
1285                         mod_timer(&recovery_timer, jiffies +
1286                                   recovery_delay[recovery_phase] * HZ);
1287                 }
1288                 spin_unlock_irq(&recovery_lock);
1289         } else
1290                 CIO_MSG_EVENT(4, "recovery: end\n");
1291 }
1292
1293 static DECLARE_WORK(recovery_work, recovery_work_func);
1294
1295 static void recovery_func(unsigned long data)
1296 {
1297         /*
1298          * We can't do our recovery in softirq context and it's not
1299          * performance critical, so we schedule it.
1300          */
1301         schedule_work(&recovery_work);
1302 }
1303
1304 static void ccw_device_schedule_recovery(void)
1305 {
1306         unsigned long flags;
1307
1308         CIO_MSG_EVENT(4, "recovery: schedule\n");
1309         spin_lock_irqsave(&recovery_lock, flags);
1310         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1311                 recovery_phase = 0;
1312                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1313         }
1314         spin_unlock_irqrestore(&recovery_lock, flags);
1315 }
1316
1317 static int purge_fn(struct device *dev, void *data)
1318 {
1319         struct ccw_device *cdev = to_ccwdev(dev);
1320         struct ccw_dev_id *id = &cdev->private->dev_id;
1321
1322         spin_lock_irq(cdev->ccwlock);
1323         if (is_blacklisted(id->ssid, id->devno) &&
1324             (cdev->private->state == DEV_STATE_OFFLINE) &&
1325             (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1326                 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1327                               id->devno);
1328                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1329                 atomic_set(&cdev->private->onoff, 0);
1330         }
1331         spin_unlock_irq(cdev->ccwlock);
1332         /* Abort loop in case of pending signal. */
1333         if (signal_pending(current))
1334                 return -EINTR;
1335
1336         return 0;
1337 }
1338
1339 /**
1340  * ccw_purge_blacklisted - purge unused, blacklisted devices
1341  *
1342  * Unregister all ccw devices that are offline and on the blacklist.
1343  */
1344 int ccw_purge_blacklisted(void)
1345 {
1346         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1347         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1348         return 0;
1349 }
1350
1351 void ccw_device_set_disconnected(struct ccw_device *cdev)
1352 {
1353         if (!cdev)
1354                 return;
1355         ccw_device_set_timeout(cdev, 0);
1356         cdev->private->flags.fake_irb = 0;
1357         cdev->private->state = DEV_STATE_DISCONNECTED;
1358         if (cdev->online)
1359                 ccw_device_schedule_recovery();
1360 }
1361
1362 void ccw_device_set_notoper(struct ccw_device *cdev)
1363 {
1364         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1365
1366         CIO_TRACE_EVENT(2, "notoper");
1367         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1368         ccw_device_set_timeout(cdev, 0);
1369         cio_disable_subchannel(sch);
1370         cdev->private->state = DEV_STATE_NOT_OPER;
1371 }
1372
1373 enum io_sch_action {
1374         IO_SCH_UNREG,
1375         IO_SCH_ORPH_UNREG,
1376         IO_SCH_ATTACH,
1377         IO_SCH_UNREG_ATTACH,
1378         IO_SCH_ORPH_ATTACH,
1379         IO_SCH_REPROBE,
1380         IO_SCH_VERIFY,
1381         IO_SCH_DISC,
1382         IO_SCH_NOP,
1383 };
1384
1385 static enum io_sch_action sch_get_action(struct subchannel *sch)
1386 {
1387         struct ccw_device *cdev;
1388
1389         cdev = sch_get_cdev(sch);
1390         if (cio_update_schib(sch)) {
1391                 /* Not operational. */
1392                 if (!cdev)
1393                         return IO_SCH_UNREG;
1394                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1395                         return IO_SCH_UNREG;
1396                 return IO_SCH_ORPH_UNREG;
1397         }
1398         /* Operational. */
1399         if (!cdev)
1400                 return IO_SCH_ATTACH;
1401         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1402                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1403                         return IO_SCH_UNREG_ATTACH;
1404                 return IO_SCH_ORPH_ATTACH;
1405         }
1406         if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1407                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1408                         return IO_SCH_UNREG;
1409                 return IO_SCH_DISC;
1410         }
1411         if (device_is_disconnected(cdev))
1412                 return IO_SCH_REPROBE;
1413         if (cdev->online)
1414                 return IO_SCH_VERIFY;
1415         return IO_SCH_NOP;
1416 }
1417
1418 /**
1419  * io_subchannel_sch_event - process subchannel event
1420  * @sch: subchannel
1421  * @process: non-zero if function is called in process context
1422  *
1423  * An unspecified event occurred for this subchannel. Adjust data according
1424  * to the current operational state of the subchannel and device. Return
1425  * zero when the event has been handled sufficiently or -EAGAIN when this
1426  * function should be called again in process context.
1427  */
1428 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1429 {
1430         unsigned long flags;
1431         struct ccw_device *cdev;
1432         struct ccw_dev_id dev_id;
1433         enum io_sch_action action;
1434         int rc = -EAGAIN;
1435
1436         spin_lock_irqsave(sch->lock, flags);
1437         if (!device_is_registered(&sch->dev))
1438                 goto out_unlock;
1439         if (work_pending(&sch->todo_work))
1440                 goto out_unlock;
1441         cdev = sch_get_cdev(sch);
1442         if (cdev && work_pending(&cdev->private->todo_work))
1443                 goto out_unlock;
1444         action = sch_get_action(sch);
1445         CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1446                       sch->schid.ssid, sch->schid.sch_no, process,
1447                       action);
1448         /* Perform immediate actions while holding the lock. */
1449         switch (action) {
1450         case IO_SCH_REPROBE:
1451                 /* Trigger device recognition. */
1452                 ccw_device_trigger_reprobe(cdev);
1453                 rc = 0;
1454                 goto out_unlock;
1455         case IO_SCH_VERIFY:
1456                 if (cdev->private->flags.resuming == 1) {
1457                         if (cio_enable_subchannel(sch, (u32)(addr_t)sch)) {
1458                                 ccw_device_set_notoper(cdev);
1459                                 break;
1460                         }
1461                 }
1462                 /* Trigger path verification. */
1463                 io_subchannel_verify(sch);
1464                 rc = 0;
1465                 goto out_unlock;
1466         case IO_SCH_DISC:
1467                 ccw_device_set_disconnected(cdev);
1468                 rc = 0;
1469                 goto out_unlock;
1470         case IO_SCH_ORPH_UNREG:
1471         case IO_SCH_ORPH_ATTACH:
1472                 ccw_device_set_disconnected(cdev);
1473                 break;
1474         case IO_SCH_UNREG_ATTACH:
1475         case IO_SCH_UNREG:
1476                 if (!cdev)
1477                         break;
1478                 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1479                         /*
1480                          * Note: delayed work triggered by this event
1481                          * and repeated calls to sch_event are synchronized
1482                          * by the above check for work_pending(cdev).
1483                          */
1484                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1485                 } else
1486                         ccw_device_set_notoper(cdev);
1487                 break;
1488         case IO_SCH_NOP:
1489                 rc = 0;
1490                 goto out_unlock;
1491         default:
1492                 break;
1493         }
1494         spin_unlock_irqrestore(sch->lock, flags);
1495         /* All other actions require process context. */
1496         if (!process)
1497                 goto out;
1498         /* Handle attached ccw device. */
1499         switch (action) {
1500         case IO_SCH_ORPH_UNREG:
1501         case IO_SCH_ORPH_ATTACH:
1502                 /* Move ccw device to orphanage. */
1503                 rc = ccw_device_move_to_orph(cdev);
1504                 if (rc)
1505                         goto out;
1506                 break;
1507         case IO_SCH_UNREG_ATTACH:
1508                 if (cdev->private->flags.resuming) {
1509                         /* Device will be handled later. */
1510                         rc = 0;
1511                         goto out;
1512                 }
1513                 /* Unregister ccw device. */
1514                 ccw_device_unregister(cdev);
1515                 break;
1516         default:
1517                 break;
1518         }
1519         /* Handle subchannel. */
1520         switch (action) {
1521         case IO_SCH_ORPH_UNREG:
1522         case IO_SCH_UNREG:
1523                 if (!cdev || !cdev->private->flags.resuming)
1524                         css_sch_device_unregister(sch);
1525                 break;
1526         case IO_SCH_ORPH_ATTACH:
1527         case IO_SCH_UNREG_ATTACH:
1528         case IO_SCH_ATTACH:
1529                 dev_id.ssid = sch->schid.ssid;
1530                 dev_id.devno = sch->schib.pmcw.dev;
1531                 cdev = get_ccwdev_by_dev_id(&dev_id);
1532                 if (!cdev) {
1533                         sch_create_and_recog_new_device(sch);
1534                         break;
1535                 }
1536                 rc = ccw_device_move_to_sch(cdev, sch);
1537                 if (rc) {
1538                         /* Release reference from get_ccwdev_by_dev_id() */
1539                         put_device(&cdev->dev);
1540                         goto out;
1541                 }
1542                 spin_lock_irqsave(sch->lock, flags);
1543                 ccw_device_trigger_reprobe(cdev);
1544                 spin_unlock_irqrestore(sch->lock, flags);
1545                 /* Release reference from get_ccwdev_by_dev_id() */
1546                 put_device(&cdev->dev);
1547                 break;
1548         default:
1549                 break;
1550         }
1551         return 0;
1552
1553 out_unlock:
1554         spin_unlock_irqrestore(sch->lock, flags);
1555 out:
1556         return rc;
1557 }
1558
1559 #ifdef CONFIG_CCW_CONSOLE
1560 static struct ccw_device console_cdev;
1561 static struct ccw_device_private console_private;
1562 static int console_cdev_in_use;
1563
1564 static DEFINE_SPINLOCK(ccw_console_lock);
1565
1566 spinlock_t * cio_get_console_lock(void)
1567 {
1568         return &ccw_console_lock;
1569 }
1570
1571 static int ccw_device_console_enable(struct ccw_device *cdev,
1572                                      struct subchannel *sch)
1573 {
1574         struct io_subchannel_private *io_priv = cio_get_console_priv();
1575         int rc;
1576
1577         /* Attach subchannel private data. */
1578         memset(io_priv, 0, sizeof(*io_priv));
1579         set_io_private(sch, io_priv);
1580         io_subchannel_init_fields(sch);
1581         rc = cio_commit_config(sch);
1582         if (rc)
1583                 return rc;
1584         sch->driver = &io_subchannel_driver;
1585         /* Initialize the ccw_device structure. */
1586         cdev->dev.parent= &sch->dev;
1587         sch_set_cdev(sch, cdev);
1588         io_subchannel_recog(cdev, sch);
1589         /* Now wait for the async. recognition to come to an end. */
1590         spin_lock_irq(cdev->ccwlock);
1591         while (!dev_fsm_final_state(cdev))
1592                 wait_cons_dev();
1593         rc = -EIO;
1594         if (cdev->private->state != DEV_STATE_OFFLINE)
1595                 goto out_unlock;
1596         ccw_device_online(cdev);
1597         while (!dev_fsm_final_state(cdev))
1598                 wait_cons_dev();
1599         if (cdev->private->state != DEV_STATE_ONLINE)
1600                 goto out_unlock;
1601         rc = 0;
1602 out_unlock:
1603         spin_unlock_irq(cdev->ccwlock);
1604         return rc;
1605 }
1606
1607 struct ccw_device *
1608 ccw_device_probe_console(void)
1609 {
1610         struct subchannel *sch;
1611         int ret;
1612
1613         if (xchg(&console_cdev_in_use, 1) != 0)
1614                 return ERR_PTR(-EBUSY);
1615         sch = cio_probe_console();
1616         if (IS_ERR(sch)) {
1617                 console_cdev_in_use = 0;
1618                 return (void *) sch;
1619         }
1620         memset(&console_cdev, 0, sizeof(struct ccw_device));
1621         memset(&console_private, 0, sizeof(struct ccw_device_private));
1622         console_cdev.private = &console_private;
1623         console_private.cdev = &console_cdev;
1624         ret = ccw_device_console_enable(&console_cdev, sch);
1625         if (ret) {
1626                 cio_release_console();
1627                 console_cdev_in_use = 0;
1628                 return ERR_PTR(ret);
1629         }
1630         console_cdev.online = 1;
1631         return &console_cdev;
1632 }
1633
1634 static int ccw_device_pm_restore(struct device *dev);
1635
1636 int ccw_device_force_console(void)
1637 {
1638         if (!console_cdev_in_use)
1639                 return -ENODEV;
1640         return ccw_device_pm_restore(&console_cdev.dev);
1641 }
1642 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1643 #endif
1644
1645 /*
1646  * get ccw_device matching the busid, but only if owned by cdrv
1647  */
1648 static int
1649 __ccwdev_check_busid(struct device *dev, void *id)
1650 {
1651         char *bus_id;
1652
1653         bus_id = id;
1654
1655         return (strcmp(bus_id, dev_name(dev)) == 0);
1656 }
1657
1658
1659 /**
1660  * get_ccwdev_by_busid() - obtain device from a bus id
1661  * @cdrv: driver the device is owned by
1662  * @bus_id: bus id of the device to be searched
1663  *
1664  * This function searches all devices owned by @cdrv for a device with a bus
1665  * id matching @bus_id.
1666  * Returns:
1667  *  If a match is found, its reference count of the found device is increased
1668  *  and it is returned; else %NULL is returned.
1669  */
1670 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1671                                        const char *bus_id)
1672 {
1673         struct device *dev;
1674         struct device_driver *drv;
1675
1676         drv = get_driver(&cdrv->driver);
1677         if (!drv)
1678                 return NULL;
1679
1680         dev = driver_find_device(drv, NULL, (void *)bus_id,
1681                                  __ccwdev_check_busid);
1682         put_driver(drv);
1683
1684         return dev ? to_ccwdev(dev) : NULL;
1685 }
1686
1687 /************************** device driver handling ************************/
1688
1689 /* This is the implementation of the ccw_driver class. The probe, remove
1690  * and release methods are initially very similar to the device_driver
1691  * implementations, with the difference that they have ccw_device
1692  * arguments.
1693  *
1694  * A ccw driver also contains the information that is needed for
1695  * device matching.
1696  */
1697 static int
1698 ccw_device_probe (struct device *dev)
1699 {
1700         struct ccw_device *cdev = to_ccwdev(dev);
1701         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1702         int ret;
1703
1704         cdev->drv = cdrv; /* to let the driver call _set_online */
1705
1706         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1707
1708         if (ret) {
1709                 cdev->drv = NULL;
1710                 return ret;
1711         }
1712
1713         return 0;
1714 }
1715
1716 static int
1717 ccw_device_remove (struct device *dev)
1718 {
1719         struct ccw_device *cdev = to_ccwdev(dev);
1720         struct ccw_driver *cdrv = cdev->drv;
1721         int ret;
1722
1723         if (cdrv->remove)
1724                 cdrv->remove(cdev);
1725         if (cdev->online) {
1726                 cdev->online = 0;
1727                 spin_lock_irq(cdev->ccwlock);
1728                 ret = ccw_device_offline(cdev);
1729                 spin_unlock_irq(cdev->ccwlock);
1730                 if (ret == 0)
1731                         wait_event(cdev->private->wait_q,
1732                                    dev_fsm_final_state(cdev));
1733                 else
1734                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1735                                       "device 0.%x.%04x\n",
1736                                       ret, cdev->private->dev_id.ssid,
1737                                       cdev->private->dev_id.devno);
1738                 /* Give up reference obtained in ccw_device_set_online(). */
1739                 put_device(&cdev->dev);
1740         }
1741         ccw_device_set_timeout(cdev, 0);
1742         cdev->drv = NULL;
1743         return 0;
1744 }
1745
1746 static void ccw_device_shutdown(struct device *dev)
1747 {
1748         struct ccw_device *cdev;
1749
1750         cdev = to_ccwdev(dev);
1751         if (cdev->drv && cdev->drv->shutdown)
1752                 cdev->drv->shutdown(cdev);
1753         disable_cmf(cdev);
1754 }
1755
1756 static int ccw_device_pm_prepare(struct device *dev)
1757 {
1758         struct ccw_device *cdev = to_ccwdev(dev);
1759
1760         if (work_pending(&cdev->private->todo_work))
1761                 return -EAGAIN;
1762         /* Fail while device is being set online/offline. */
1763         if (atomic_read(&cdev->private->onoff))
1764                 return -EAGAIN;
1765
1766         if (cdev->online && cdev->drv && cdev->drv->prepare)
1767                 return cdev->drv->prepare(cdev);
1768
1769         return 0;
1770 }
1771
1772 static void ccw_device_pm_complete(struct device *dev)
1773 {
1774         struct ccw_device *cdev = to_ccwdev(dev);
1775
1776         if (cdev->online && cdev->drv && cdev->drv->complete)
1777                 cdev->drv->complete(cdev);
1778 }
1779
1780 static int ccw_device_pm_freeze(struct device *dev)
1781 {
1782         struct ccw_device *cdev = to_ccwdev(dev);
1783         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1784         int ret, cm_enabled;
1785
1786         /* Fail suspend while device is in transistional state. */
1787         if (!dev_fsm_final_state(cdev))
1788                 return -EAGAIN;
1789         if (!cdev->online)
1790                 return 0;
1791         if (cdev->drv && cdev->drv->freeze) {
1792                 ret = cdev->drv->freeze(cdev);
1793                 if (ret)
1794                         return ret;
1795         }
1796
1797         spin_lock_irq(sch->lock);
1798         cm_enabled = cdev->private->cmb != NULL;
1799         spin_unlock_irq(sch->lock);
1800         if (cm_enabled) {
1801                 /* Don't have the css write on memory. */
1802                 ret = ccw_set_cmf(cdev, 0);
1803                 if (ret)
1804                         return ret;
1805         }
1806         /* From here on, disallow device driver I/O. */
1807         spin_lock_irq(sch->lock);
1808         ret = cio_disable_subchannel(sch);
1809         spin_unlock_irq(sch->lock);
1810
1811         return ret;
1812 }
1813
1814 static int ccw_device_pm_thaw(struct device *dev)
1815 {
1816         struct ccw_device *cdev = to_ccwdev(dev);
1817         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1818         int ret, cm_enabled;
1819
1820         if (!cdev->online)
1821                 return 0;
1822
1823         spin_lock_irq(sch->lock);
1824         /* Allow device driver I/O again. */
1825         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1826         cm_enabled = cdev->private->cmb != NULL;
1827         spin_unlock_irq(sch->lock);
1828         if (ret)
1829                 return ret;
1830
1831         if (cm_enabled) {
1832                 ret = ccw_set_cmf(cdev, 1);
1833                 if (ret)
1834                         return ret;
1835         }
1836
1837         if (cdev->drv && cdev->drv->thaw)
1838                 ret = cdev->drv->thaw(cdev);
1839
1840         return ret;
1841 }
1842
1843 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1844 {
1845         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1846
1847         spin_lock_irq(sch->lock);
1848         if (cio_is_console(sch->schid)) {
1849                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1850                 goto out_unlock;
1851         }
1852         /*
1853          * While we were sleeping, devices may have gone or become
1854          * available again. Kick re-detection.
1855          */
1856         cdev->private->flags.resuming = 1;
1857         cdev->private->path_new_mask = LPM_ANYPATH;
1858         css_schedule_eval(sch->schid);
1859         spin_unlock_irq(sch->lock);
1860         css_complete_work();
1861
1862         /* cdev may have been moved to a different subchannel. */
1863         sch = to_subchannel(cdev->dev.parent);
1864         spin_lock_irq(sch->lock);
1865         if (cdev->private->state != DEV_STATE_ONLINE &&
1866             cdev->private->state != DEV_STATE_OFFLINE)
1867                 goto out_unlock;
1868
1869         ccw_device_recognition(cdev);
1870         spin_unlock_irq(sch->lock);
1871         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1872                    cdev->private->state == DEV_STATE_DISCONNECTED);
1873         spin_lock_irq(sch->lock);
1874
1875 out_unlock:
1876         cdev->private->flags.resuming = 0;
1877         spin_unlock_irq(sch->lock);
1878 }
1879
1880 static int resume_handle_boxed(struct ccw_device *cdev)
1881 {
1882         cdev->private->state = DEV_STATE_BOXED;
1883         if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1884                 return 0;
1885         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1886         return -ENODEV;
1887 }
1888
1889 static int resume_handle_disc(struct ccw_device *cdev)
1890 {
1891         cdev->private->state = DEV_STATE_DISCONNECTED;
1892         if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1893                 return 0;
1894         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1895         return -ENODEV;
1896 }
1897
1898 static int ccw_device_pm_restore(struct device *dev)
1899 {
1900         struct ccw_device *cdev = to_ccwdev(dev);
1901         struct subchannel *sch;
1902         int ret = 0;
1903
1904         __ccw_device_pm_restore(cdev);
1905         sch = to_subchannel(cdev->dev.parent);
1906         spin_lock_irq(sch->lock);
1907         if (cio_is_console(sch->schid))
1908                 goto out_restore;
1909
1910         /* check recognition results */
1911         switch (cdev->private->state) {
1912         case DEV_STATE_OFFLINE:
1913         case DEV_STATE_ONLINE:
1914                 cdev->private->flags.donotify = 0;
1915                 break;
1916         case DEV_STATE_BOXED:
1917                 ret = resume_handle_boxed(cdev);
1918                 if (ret)
1919                         goto out_unlock;
1920                 goto out_restore;
1921         default:
1922                 ret = resume_handle_disc(cdev);
1923                 if (ret)
1924                         goto out_unlock;
1925                 goto out_restore;
1926         }
1927         /* check if the device type has changed */
1928         if (!ccw_device_test_sense_data(cdev)) {
1929                 ccw_device_update_sense_data(cdev);
1930                 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1931                 ret = -ENODEV;
1932                 goto out_unlock;
1933         }
1934         if (!cdev->online)
1935                 goto out_unlock;
1936
1937         if (ccw_device_online(cdev)) {
1938                 ret = resume_handle_disc(cdev);
1939                 if (ret)
1940                         goto out_unlock;
1941                 goto out_restore;
1942         }
1943         spin_unlock_irq(sch->lock);
1944         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1945         spin_lock_irq(sch->lock);
1946
1947         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1948                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1949                 ret = -ENODEV;
1950                 goto out_unlock;
1951         }
1952
1953         /* reenable cmf, if needed */
1954         if (cdev->private->cmb) {
1955                 spin_unlock_irq(sch->lock);
1956                 ret = ccw_set_cmf(cdev, 1);
1957                 spin_lock_irq(sch->lock);
1958                 if (ret) {
1959                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
1960                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
1961                                       cdev->private->dev_id.devno, ret);
1962                         ret = 0;
1963                 }
1964         }
1965
1966 out_restore:
1967         spin_unlock_irq(sch->lock);
1968         if (cdev->online && cdev->drv && cdev->drv->restore)
1969                 ret = cdev->drv->restore(cdev);
1970         return ret;
1971
1972 out_unlock:
1973         spin_unlock_irq(sch->lock);
1974         return ret;
1975 }
1976
1977 static const struct dev_pm_ops ccw_pm_ops = {
1978         .prepare = ccw_device_pm_prepare,
1979         .complete = ccw_device_pm_complete,
1980         .freeze = ccw_device_pm_freeze,
1981         .thaw = ccw_device_pm_thaw,
1982         .restore = ccw_device_pm_restore,
1983 };
1984
1985 static struct bus_type ccw_bus_type = {
1986         .name   = "ccw",
1987         .match  = ccw_bus_match,
1988         .uevent = ccw_uevent,
1989         .probe  = ccw_device_probe,
1990         .remove = ccw_device_remove,
1991         .shutdown = ccw_device_shutdown,
1992         .pm = &ccw_pm_ops,
1993 };
1994
1995 /**
1996  * ccw_driver_register() - register a ccw driver
1997  * @cdriver: driver to be registered
1998  *
1999  * This function is mainly a wrapper around driver_register().
2000  * Returns:
2001  *   %0 on success and a negative error value on failure.
2002  */
2003 int ccw_driver_register(struct ccw_driver *cdriver)
2004 {
2005         struct device_driver *drv = &cdriver->driver;
2006
2007         drv->bus = &ccw_bus_type;
2008
2009         return driver_register(drv);
2010 }
2011
2012 /**
2013  * ccw_driver_unregister() - deregister a ccw driver
2014  * @cdriver: driver to be deregistered
2015  *
2016  * This function is mainly a wrapper around driver_unregister().
2017  */
2018 void ccw_driver_unregister(struct ccw_driver *cdriver)
2019 {
2020         driver_unregister(&cdriver->driver);
2021 }
2022
2023 /* Helper func for qdio. */
2024 struct subchannel_id
2025 ccw_device_get_subchannel_id(struct ccw_device *cdev)
2026 {
2027         struct subchannel *sch;
2028
2029         sch = to_subchannel(cdev->dev.parent);
2030         return sch->schid;
2031 }
2032
2033 static void ccw_device_todo(struct work_struct *work)
2034 {
2035         struct ccw_device_private *priv;
2036         struct ccw_device *cdev;
2037         struct subchannel *sch;
2038         enum cdev_todo todo;
2039
2040         priv = container_of(work, struct ccw_device_private, todo_work);
2041         cdev = priv->cdev;
2042         sch = to_subchannel(cdev->dev.parent);
2043         /* Find out todo. */
2044         spin_lock_irq(cdev->ccwlock);
2045         todo = priv->todo;
2046         priv->todo = CDEV_TODO_NOTHING;
2047         CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2048                       priv->dev_id.ssid, priv->dev_id.devno, todo);
2049         spin_unlock_irq(cdev->ccwlock);
2050         /* Perform todo. */
2051         switch (todo) {
2052         case CDEV_TODO_ENABLE_CMF:
2053                 cmf_reenable(cdev);
2054                 break;
2055         case CDEV_TODO_REBIND:
2056                 ccw_device_do_unbind_bind(cdev);
2057                 break;
2058         case CDEV_TODO_REGISTER:
2059                 io_subchannel_register(cdev);
2060                 break;
2061         case CDEV_TODO_UNREG_EVAL:
2062                 if (!sch_is_pseudo_sch(sch))
2063                         css_schedule_eval(sch->schid);
2064                 /* fall-through */
2065         case CDEV_TODO_UNREG:
2066                 if (sch_is_pseudo_sch(sch))
2067                         ccw_device_unregister(cdev);
2068                 else
2069                         ccw_device_call_sch_unregister(cdev);
2070                 break;
2071         default:
2072                 break;
2073         }
2074         /* Release workqueue ref. */
2075         put_device(&cdev->dev);
2076 }
2077
2078 /**
2079  * ccw_device_sched_todo - schedule ccw device operation
2080  * @cdev: ccw device
2081  * @todo: todo
2082  *
2083  * Schedule the operation identified by @todo to be performed on the slow path
2084  * workqueue. Do nothing if another operation with higher priority is already
2085  * scheduled. Needs to be called with ccwdev lock held.
2086  */
2087 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2088 {
2089         CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2090                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2091                       todo);
2092         if (cdev->private->todo >= todo)
2093                 return;
2094         cdev->private->todo = todo;
2095         /* Get workqueue ref. */
2096         if (!get_device(&cdev->dev))
2097                 return;
2098         if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2099                 /* Already queued, release workqueue ref. */
2100                 put_device(&cdev->dev);
2101         }
2102 }
2103
2104 /**
2105  * ccw_device_siosl() - initiate logging
2106  * @cdev: ccw device
2107  *
2108  * This function is used to invoke model-dependent logging within the channel
2109  * subsystem.
2110  */
2111 int ccw_device_siosl(struct ccw_device *cdev)
2112 {
2113         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2114
2115         return chsc_siosl(sch->schid);
2116 }
2117 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2118
2119 MODULE_LICENSE("GPL");
2120 EXPORT_SYMBOL(ccw_device_set_online);
2121 EXPORT_SYMBOL(ccw_device_set_offline);
2122 EXPORT_SYMBOL(ccw_driver_register);
2123 EXPORT_SYMBOL(ccw_driver_unregister);
2124 EXPORT_SYMBOL(get_ccwdev_by_busid);
2125 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);