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 #include <linux/kernel_stat.h>
  25
  26 #include <asm/ccwdev.h>
  27 #include <asm/cio.h>
  28 #include <asm/param.h>          /* HZ */
  29 #include <asm/cmb.h>
  30 #include <asm/isc.h>
  31
  32 #include "chp.h"
  33 #include "cio.h"
  34 #include "cio_debug.h"
  35 #include "css.h"
  36 #include "device.h"
  37 #include "ioasm.h"
  38 #include "io_sch.h"
  39 #include "blacklist.h"
  40 #include "chsc.h"
  41
  42 static struct timer_list recovery_timer;
  43 static DEFINE_SPINLOCK(recovery_lock);
  44 static int recovery_phase;
  45 static const unsigned long recovery_delay[] = { 3, 30, 300 };
  46
  47 /******************* bus type handling ***********************/
  48
  49 /* The Linux driver model distinguishes between a bus type and
  50  * the bus itself. Of course we only have one channel
  51  * subsystem driver and one channel system per machine, but
  52  * we still use the abstraction. T.R. says it's a good idea. */
  53 static int
  54 ccw_bus_match (struct device * dev, struct device_driver * drv)
  55 {
  56         struct ccw_device *cdev = to_ccwdev(dev);
  57         struct ccw_driver *cdrv = to_ccwdrv(drv);
  58         const struct ccw_device_id *ids = cdrv->ids, *found;
  59
  60         if (!ids)
  61                 return 0;
  62
  63         found = ccw_device_id_match(ids, &cdev->id);
  64         if (!found)
  65                 return 0;
  66
  67         cdev->id.driver_info = found->driver_info;
  68
  69         return 1;
  70 }
  71
  72 /* Store modalias string delimited by prefix/suffix string into buffer with
  73  * specified size. Return length of resulting string (excluding trailing '\0')
  74  * even if string doesn't fit buffer (snprintf semantics). */
  75 static int snprint_alias(char *buf, size_t size,
  76                          struct ccw_device_id *id, const char *suffix)
  77 {
  78         int len;
  79
  80         len = snprintf(buf, size, "ccw:t%04Xm%02X", id->cu_type, id->cu_model);
  81         if (len > size)
  82                 return len;
  83         buf += len;
  84         size -= len;
  85
  86         if (id->dev_type != 0)
  87                 len += snprintf(buf, size, "dt%04Xdm%02X%s", id->dev_type,
  88                                 id->dev_model, suffix);
  89         else
  90                 len += snprintf(buf, size, "dtdm%s", suffix);
  91
  92         return len;
  93 }
  94
  95 /* Set up environment variables for ccw device uevent. Return 0 on success,
  96  * non-zero otherwise. */
  97 static int ccw_uevent(struct device *dev, struct kobj_uevent_env *env)
  98 {
  99         struct ccw_device *cdev = to_ccwdev(dev);
 100         struct ccw_device_id *id = &(cdev->id);
 101         int ret;
 102         char modalias_buf[30];
 103
 104         /* CU_TYPE= */
 105         ret = add_uevent_var(env, "CU_TYPE=%04X", id->cu_type);
 106         if (ret)
 107                 return ret;
 108
 109         /* CU_MODEL= */
 110         ret = add_uevent_var(env, "CU_MODEL=%02X", id->cu_model);
 111         if (ret)
 112                 return ret;
 113
 114         /* The next two can be zero, that's ok for us */
 115         /* DEV_TYPE= */
 116         ret = add_uevent_var(env, "DEV_TYPE=%04X", id->dev_type);
 117         if (ret)
 118                 return ret;
 119
 120         /* DEV_MODEL= */
 121         ret = add_uevent_var(env, "DEV_MODEL=%02X", id->dev_model);
 122         if (ret)
 123                 return ret;
 124
 125         /* MODALIAS=  */
 126         snprint_alias(modalias_buf, sizeof(modalias_buf), id, "");
 127         ret = add_uevent_var(env, "MODALIAS=%s", modalias_buf);
 128         return ret;
 129 }
 130
 131 static struct bus_type ccw_bus_type;
 132
 133 static void io_subchannel_irq(struct subchannel *);
 134 static int io_subchannel_probe(struct subchannel *);
 135 static int io_subchannel_remove(struct subchannel *);
 136 static void io_subchannel_shutdown(struct subchannel *);
 137 static int io_subchannel_sch_event(struct subchannel *, int);
 138 static int io_subchannel_chp_event(struct subchannel *, struct chp_link *,
 139                                    int);
 140 static void recovery_func(unsigned long data);
 141 wait_queue_head_t ccw_device_init_wq;
 142 atomic_t ccw_device_init_count;
 143
 144 static struct css_device_id io_subchannel_ids[] = {
 145         { .match_flags = 0x1, .type = SUBCHANNEL_TYPE_IO, },
 146         { /* end of list */ },
 147 };
 148 MODULE_DEVICE_TABLE(css, io_subchannel_ids);
 149
 150 static int io_subchannel_prepare(struct subchannel *sch)
 151 {
 152         struct ccw_device *cdev;
 153         /*
 154          * Don't allow suspend while a ccw device registration
 155          * is still outstanding.
 156          */
 157         cdev = sch_get_cdev(sch);
 158         if (cdev && !device_is_registered(&cdev->dev))
 159                 return -EAGAIN;
 160         return 0;
 161 }
 162
 163 static int io_subchannel_settle(void)
 164 {
 165         int ret;
 166
 167         ret = wait_event_interruptible(ccw_device_init_wq,
 168                                 atomic_read(&ccw_device_init_count) == 0);
 169         if (ret)
 170                 return -EINTR;
 171         flush_workqueue(cio_work_q);
 172         return 0;
 173 }
 174
 175 static struct css_driver io_subchannel_driver = {
 176         .drv = {
 177                 .owner = THIS_MODULE,
 178                 .name = "io_subchannel",
 179         },
 180         .subchannel_type = io_subchannel_ids,
 181         .irq = io_subchannel_irq,
 182         .sch_event = io_subchannel_sch_event,
 183         .chp_event = io_subchannel_chp_event,
 184         .probe = io_subchannel_probe,
 185         .remove = io_subchannel_remove,
 186         .shutdown = io_subchannel_shutdown,
 187         .prepare = io_subchannel_prepare,
 188         .settle = io_subchannel_settle,
 189 };
 190
 191 int __init io_subchannel_init(void)
 192 {
 193         int ret;
 194
 195         init_waitqueue_head(&ccw_device_init_wq);
 196         atomic_set(&ccw_device_init_count, 0);
 197         setup_timer(&recovery_timer, recovery_func, 0);
 198
 199         ret = bus_register(&ccw_bus_type);
 200         if (ret)
 201                 return ret;
 202         ret = css_driver_register(&io_subchannel_driver);
 203         if (ret)
 204                 bus_unregister(&ccw_bus_type);
 205
 206         return ret;
 207 }
 208
 209
 210 /************************ device handling **************************/
 211
 212 /*
 213  * A ccw_device has some interfaces in sysfs in addition to the
 214  * standard ones.
 215  * The following entries are designed to export the information which
 216  * resided in 2.4 in /proc/subchannels. Subchannel and device number
 217  * are obvious, so they don't have an entry :)
 218  * TODO: Split chpids and pimpampom up? Where is "in use" in the tree?
 219  */
 220 static ssize_t
 221 chpids_show (struct device * dev, struct device_attribute *attr, char * buf)
 222 {
 223         struct subchannel *sch = to_subchannel(dev);
 224         struct chsc_ssd_info *ssd = &sch->ssd_info;
 225         ssize_t ret = 0;
 226         int chp;
 227         int mask;
 228
 229         for (chp = 0; chp < 8; chp++) {
 230                 mask = 0x80 >> chp;
 231                 if (ssd->path_mask & mask)
 232                         ret += sprintf(buf + ret, "%02x ", ssd->chpid[chp].id);
 233                 else
 234                         ret += sprintf(buf + ret, "00 ");
 235         }
 236         ret += sprintf (buf+ret, "\n");
 237         return min((ssize_t)PAGE_SIZE, ret);
 238 }
 239
 240 static ssize_t
 241 pimpampom_show (struct device * dev, struct device_attribute *attr, char * buf)
 242 {
 243         struct subchannel *sch = to_subchannel(dev);
 244         struct pmcw *pmcw = &sch->schib.pmcw;
 245
 246         return sprintf (buf, "%02x %02x %02x\n",
 247                         pmcw->pim, pmcw->pam, pmcw->pom);
 248 }
 249
 250 static ssize_t
 251 devtype_show (struct device *dev, struct device_attribute *attr, char *buf)
 252 {
 253         struct ccw_device *cdev = to_ccwdev(dev);
 254         struct ccw_device_id *id = &(cdev->id);
 255
 256         if (id->dev_type != 0)
 257                 return sprintf(buf, "%04x/%02x\n",
 258                                 id->dev_type, id->dev_model);
 259         else
 260                 return sprintf(buf, "n/a\n");
 261 }
 262
 263 static ssize_t
 264 cutype_show (struct device *dev, struct device_attribute *attr, char *buf)
 265 {
 266         struct ccw_device *cdev = to_ccwdev(dev);
 267         struct ccw_device_id *id = &(cdev->id);
 268
 269         return sprintf(buf, "%04x/%02x\n",
 270                        id->cu_type, id->cu_model);
 271 }
 272
 273 static ssize_t
 274 modalias_show (struct device *dev, struct device_attribute *attr, char *buf)
 275 {
 276         struct ccw_device *cdev = to_ccwdev(dev);
 277         struct ccw_device_id *id = &(cdev->id);
 278         int len;
 279
 280         len = snprint_alias(buf, PAGE_SIZE, id, "\n");
 281
 282         return len > PAGE_SIZE ? PAGE_SIZE : len;
 283 }
 284
 285 static ssize_t
 286 online_show (struct device *dev, struct device_attribute *attr, char *buf)
 287 {
 288         struct ccw_device *cdev = to_ccwdev(dev);
 289
 290         return sprintf(buf, cdev->online ? "1\n" : "0\n");
 291 }
 292
 293 int ccw_device_is_orphan(struct ccw_device *cdev)
 294 {
 295         return sch_is_pseudo_sch(to_subchannel(cdev->dev.parent));
 296 }
 297
 298 static void ccw_device_unregister(struct ccw_device *cdev)
 299 {
 300         if (device_is_registered(&cdev->dev)) {
 301                 /* Undo device_add(). */
 302                 device_del(&cdev->dev);
 303         }
 304         if (cdev->private->flags.initialized) {
 305                 cdev->private->flags.initialized = 0;
 306                 /* Release reference from device_initialize(). */
 307                 put_device(&cdev->dev);
 308         }
 309 }
 310
 311 static void io_subchannel_quiesce(struct subchannel *);
 312
 313 /**
 314  * ccw_device_set_offline() - disable a ccw device for I/O
 315  * @cdev: target ccw device
 316  *
 317  * This function calls the driver's set_offline() function for @cdev, if
 318  * given, and then disables @cdev.
 319  * Returns:
 320  *   %0 on success and a negative error value on failure.
 321  * Context:
 322  *  enabled, ccw device lock not held
 323  */
 324 int ccw_device_set_offline(struct ccw_device *cdev)
 325 {
 326         struct subchannel *sch;
 327         int ret, state;
 328
 329         if (!cdev)
 330                 return -ENODEV;
 331         if (!cdev->online || !cdev->drv)
 332                 return -EINVAL;
 333
 334         if (cdev->drv->set_offline) {
 335                 ret = cdev->drv->set_offline(cdev);
 336                 if (ret != 0)
 337                         return ret;
 338         }
 339         cdev->online = 0;
 340         spin_lock_irq(cdev->ccwlock);
 341         sch = to_subchannel(cdev->dev.parent);
 342         /* Wait until a final state or DISCONNECTED is reached */
 343         while (!dev_fsm_final_state(cdev) &&
 344                cdev->private->state != DEV_STATE_DISCONNECTED) {
 345                 spin_unlock_irq(cdev->ccwlock);
 346                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 347                            cdev->private->state == DEV_STATE_DISCONNECTED));
 348                 spin_lock_irq(cdev->ccwlock);
 349         }
 350         do {
 351                 ret = ccw_device_offline(cdev);
 352                 if (!ret)
 353                         break;
 354                 CIO_MSG_EVENT(0, "ccw_device_offline returned %d, device "
 355                               "0.%x.%04x\n", ret, cdev->private->dev_id.ssid,
 356                               cdev->private->dev_id.devno);
 357                 if (ret != -EBUSY)
 358                         goto error;
 359                 state = cdev->private->state;
 360                 spin_unlock_irq(cdev->ccwlock);
 361                 io_subchannel_quiesce(sch);
 362                 spin_lock_irq(cdev->ccwlock);
 363                 cdev->private->state = state;
 364         } while (ret == -EBUSY);
 365         spin_unlock_irq(cdev->ccwlock);
 366         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 367                    cdev->private->state == DEV_STATE_DISCONNECTED));
 368         /* Inform the user if set offline failed. */
 369         if (cdev->private->state == DEV_STATE_BOXED) {
 370                 pr_warning("%s: The device entered boxed state while "
 371                            "being set offline\n", dev_name(&cdev->dev));
 372         } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 373                 pr_warning("%s: The device stopped operating while "
 374                            "being set offline\n", dev_name(&cdev->dev));
 375         }
 376         /* Give up reference from ccw_device_set_online(). */
 377         put_device(&cdev->dev);
 378         return 0;
 379
 380 error:
 381         cdev->private->state = DEV_STATE_OFFLINE;
 382         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
 383         spin_unlock_irq(cdev->ccwlock);
 384         /* Give up reference from ccw_device_set_online(). */
 385         put_device(&cdev->dev);
 386         return -ENODEV;
 387 }
 388
 389 /**
 390  * ccw_device_set_online() - enable a ccw device for I/O
 391  * @cdev: target ccw device
 392  *
 393  * This function first enables @cdev and then calls the driver's set_online()
 394  * function for @cdev, if given. If set_online() returns an error, @cdev is
 395  * disabled again.
 396  * Returns:
 397  *   %0 on success and a negative error value on failure.
 398  * Context:
 399  *  enabled, ccw device lock not held
 400  */
 401 int ccw_device_set_online(struct ccw_device *cdev)
 402 {
 403         int ret;
 404         int ret2;
 405
 406         if (!cdev)
 407                 return -ENODEV;
 408         if (cdev->online || !cdev->drv)
 409                 return -EINVAL;
 410         /* Hold on to an extra reference while device is online. */
 411         if (!get_device(&cdev->dev))
 412                 return -ENODEV;
 413
 414         spin_lock_irq(cdev->ccwlock);
 415         ret = ccw_device_online(cdev);
 416         spin_unlock_irq(cdev->ccwlock);
 417         if (ret == 0)
 418                 wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
 419         else {
 420                 CIO_MSG_EVENT(0, "ccw_device_online returned %d, "
 421                               "device 0.%x.%04x\n",
 422                               ret, cdev->private->dev_id.ssid,
 423                               cdev->private->dev_id.devno);
 424                 /* Give up online reference since onlining failed. */
 425                 put_device(&cdev->dev);
 426                 return ret;
 427         }
 428         spin_lock_irq(cdev->ccwlock);
 429         /* Check if online processing was successful */
 430         if ((cdev->private->state != DEV_STATE_ONLINE) &&
 431             (cdev->private->state != DEV_STATE_W4SENSE)) {
 432                 spin_unlock_irq(cdev->ccwlock);
 433                 /* Inform the user that set online failed. */
 434                 if (cdev->private->state == DEV_STATE_BOXED) {
 435                         pr_warning("%s: Setting the device online failed "
 436                                    "because it is boxed\n",
 437                                    dev_name(&cdev->dev));
 438                 } else if (cdev->private->state == DEV_STATE_NOT_OPER) {
 439                         pr_warning("%s: Setting the device online failed "
 440                                    "because it is not operational\n",
 441                                    dev_name(&cdev->dev));
 442                 }
 443                 /* Give up online reference since onlining failed. */
 444                 put_device(&cdev->dev);
 445                 return -ENODEV;
 446         }
 447         spin_unlock_irq(cdev->ccwlock);
 448         if (cdev->drv->set_online)
 449                 ret = cdev->drv->set_online(cdev);
 450         if (ret)
 451                 goto rollback;
 452         cdev->online = 1;
 453         return 0;
 454
 455 rollback:
 456         spin_lock_irq(cdev->ccwlock);
 457         /* Wait until a final state or DISCONNECTED is reached */
 458         while (!dev_fsm_final_state(cdev) &&
 459                cdev->private->state != DEV_STATE_DISCONNECTED) {
 460                 spin_unlock_irq(cdev->ccwlock);
 461                 wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 462                            cdev->private->state == DEV_STATE_DISCONNECTED));
 463                 spin_lock_irq(cdev->ccwlock);
 464         }
 465         ret2 = ccw_device_offline(cdev);
 466         if (ret2)
 467                 goto error;
 468         spin_unlock_irq(cdev->ccwlock);
 469         wait_event(cdev->private->wait_q, (dev_fsm_final_state(cdev) ||
 470                    cdev->private->state == DEV_STATE_DISCONNECTED));
 471         /* Give up online reference since onlining failed. */
 472         put_device(&cdev->dev);
 473         return ret;
 474
 475 error:
 476         CIO_MSG_EVENT(0, "rollback ccw_device_offline returned %d, "
 477                       "device 0.%x.%04x\n",
 478                       ret2, cdev->private->dev_id.ssid,
 479                       cdev->private->dev_id.devno);
 480         cdev->private->state = DEV_STATE_OFFLINE;
 481         spin_unlock_irq(cdev->ccwlock);
 482         /* Give up online reference since onlining failed. */
 483         put_device(&cdev->dev);
 484         return ret;
 485 }
 486
 487 static int online_store_handle_offline(struct ccw_device *cdev)
 488 {
 489         if (cdev->private->state == DEV_STATE_DISCONNECTED) {
 490                 spin_lock_irq(cdev->ccwlock);
 491                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG_EVAL);
 492                 spin_unlock_irq(cdev->ccwlock);
 493                 return 0;
 494         }
 495         if (cdev->drv && cdev->drv->set_offline)
 496                 return ccw_device_set_offline(cdev);
 497         return -EINVAL;
 498 }
 499
 500 static int online_store_recog_and_online(struct ccw_device *cdev)
 501 {
 502         /* Do device recognition, if needed. */
 503         if (cdev->private->state == DEV_STATE_BOXED) {
 504                 spin_lock_irq(cdev->ccwlock);
 505                 ccw_device_recognition(cdev);
 506                 spin_unlock_irq(cdev->ccwlock);
 507                 wait_event(cdev->private->wait_q,
 508                            cdev->private->flags.recog_done);
 509                 if (cdev->private->state != DEV_STATE_OFFLINE)
 510                         /* recognition failed */
 511                         return -EAGAIN;
 512         }
 513         if (cdev->drv && cdev->drv->set_online)
 514                 return ccw_device_set_online(cdev);
 515         return -EINVAL;
 516 }
 517
 518 static int online_store_handle_online(struct ccw_device *cdev, int force)
 519 {
 520         int ret;
 521
 522         ret = online_store_recog_and_online(cdev);
 523         if (ret && !force)
 524                 return ret;
 525         if (force && cdev->private->state == DEV_STATE_BOXED) {
 526                 ret = ccw_device_stlck(cdev);
 527                 if (ret)
 528                         return ret;
 529                 if (cdev->id.cu_type == 0)
 530                         cdev->private->state = DEV_STATE_NOT_OPER;
 531                 ret = online_store_recog_and_online(cdev);
 532                 if (ret)
 533                         return ret;
 534         }
 535         return 0;
 536 }
 537
 538 static ssize_t online_store (struct device *dev, struct device_attribute *attr,
 539                              const char *buf, size_t count)
 540 {
 541         struct ccw_device *cdev = to_ccwdev(dev);
 542         int force, ret;
 543         unsigned long i;
 544
 545         /* Prevent conflict between multiple on-/offline processing requests. */
 546         if (atomic_cmpxchg(&cdev->private->onoff, 0, 1) != 0)
 547                 return -EAGAIN;
 548         /* Prevent conflict between internal I/Os and on-/offline processing. */
 549         if (!dev_fsm_final_state(cdev) &&
 550             cdev->private->state != DEV_STATE_DISCONNECTED) {
 551                 ret = -EAGAIN;
 552                 goto out_onoff;
 553         }
 554         /* Prevent conflict between pending work and on-/offline processing.*/
 555         if (work_pending(&cdev->private->todo_work)) {
 556                 ret = -EAGAIN;
 557                 goto out_onoff;
 558         }
 559
 560         if (cdev->drv && !try_module_get(cdev->drv->driver.owner)) {
 561                 ret = -EINVAL;
 562                 goto out_onoff;
 563         }
 564         if (!strncmp(buf, "force\n", count)) {
 565                 force = 1;
 566                 i = 1;
 567                 ret = 0;
 568         } else {
 569                 force = 0;
 570                 ret = strict_strtoul(buf, 16, &i);
 571         }
 572         if (ret)
 573                 goto out;
 574         switch (i) {
 575         case 0:
 576                 ret = online_store_handle_offline(cdev);
 577                 break;
 578         case 1:
 579                 ret = online_store_handle_online(cdev, force);
 580                 break;
 581         default:
 582                 ret = -EINVAL;
 583         }
 584 out:
 585         if (cdev->drv)
 586                 module_put(cdev->drv->driver.owner);
 587 out_onoff:
 588         atomic_set(&cdev->private->onoff, 0);
 589         return (ret < 0) ? ret : count;
 590 }
 591
 592 static ssize_t
 593 available_show (struct device *dev, struct device_attribute *attr, char *buf)
 594 {
 595         struct ccw_device *cdev = to_ccwdev(dev);
 596         struct subchannel *sch;
 597
 598         if (ccw_device_is_orphan(cdev))
 599                 return sprintf(buf, "no device\n");
 600         switch (cdev->private->state) {
 601         case DEV_STATE_BOXED:
 602                 return sprintf(buf, "boxed\n");
 603         case DEV_STATE_DISCONNECTED:
 604         case DEV_STATE_DISCONNECTED_SENSE_ID:
 605         case DEV_STATE_NOT_OPER:
 606                 sch = to_subchannel(dev->parent);
 607                 if (!sch->lpm)
 608                         return sprintf(buf, "no path\n");
 609                 else
 610                         return sprintf(buf, "no device\n");
 611         default:
 612                 /* All other states considered fine. */
 613                 return sprintf(buf, "good\n");
 614         }
 615 }
 616
 617 static ssize_t
 618 initiate_logging(struct device *dev, struct device_attribute *attr,
 619                  const char *buf, size_t count)
 620 {
 621         struct subchannel *sch = to_subchannel(dev);
 622         int rc;
 623
 624         rc = chsc_siosl(sch->schid);
 625         if (rc < 0) {
 626                 pr_warning("Logging for subchannel 0.%x.%04x failed with "
 627                            "errno=%d\n",
 628                            sch->schid.ssid, sch->schid.sch_no, rc);
 629                 return rc;
 630         }
 631         pr_notice("Logging for subchannel 0.%x.%04x was triggered\n",
 632                   sch->schid.ssid, sch->schid.sch_no);
 633         return count;
 634 }
 635
 636 static DEVICE_ATTR(chpids, 0444, chpids_show, NULL);
 637 static DEVICE_ATTR(pimpampom, 0444, pimpampom_show, NULL);
 638 static DEVICE_ATTR(devtype, 0444, devtype_show, NULL);
 639 static DEVICE_ATTR(cutype, 0444, cutype_show, NULL);
 640 static DEVICE_ATTR(modalias, 0444, modalias_show, NULL);
 641 static DEVICE_ATTR(online, 0644, online_show, online_store);
 642 static DEVICE_ATTR(availability, 0444, available_show, NULL);
 643 static DEVICE_ATTR(logging, 0200, NULL, initiate_logging);
 644
 645 static struct attribute *io_subchannel_attrs[] = {
 646         &dev_attr_chpids.attr,
 647         &dev_attr_pimpampom.attr,
 648         &dev_attr_logging.attr,
 649         NULL,
 650 };
 651
 652 static struct attribute_group io_subchannel_attr_group = {
 653         .attrs = io_subchannel_attrs,
 654 };
 655
 656 static struct attribute * ccwdev_attrs[] = {
 657         &dev_attr_devtype.attr,
 658         &dev_attr_cutype.attr,
 659         &dev_attr_modalias.attr,
 660         &dev_attr_online.attr,
 661         &dev_attr_cmb_enable.attr,
 662         &dev_attr_availability.attr,
 663         NULL,
 664 };
 665
 666 static struct attribute_group ccwdev_attr_group = {
 667         .attrs = ccwdev_attrs,
 668 };
 669
 670 static const struct attribute_group *ccwdev_attr_groups[] = {
 671         &ccwdev_attr_group,
 672         NULL,
 673 };
 674
 675 /* this is a simple abstraction for device_register that sets the
 676  * correct bus type and adds the bus specific files */
 677 static int ccw_device_register(struct ccw_device *cdev)
 678 {
 679         struct device *dev = &cdev->dev;
 680         int ret;
 681
 682         dev->bus = &ccw_bus_type;
 683         ret = dev_set_name(&cdev->dev, "0.%x.%04x", cdev->private->dev_id.ssid,
 684                            cdev->private->dev_id.devno);
 685         if (ret)
 686                 return ret;
 687         return device_add(dev);
 688 }
 689
 690 static int match_dev_id(struct device *dev, void *data)
 691 {
 692         struct ccw_device *cdev = to_ccwdev(dev);
 693         struct ccw_dev_id *dev_id = data;
 694
 695         return ccw_dev_id_is_equal(&cdev->private->dev_id, dev_id);
 696 }
 697
 698 static struct ccw_device *get_ccwdev_by_dev_id(struct ccw_dev_id *dev_id)
 699 {
 700         struct device *dev;
 701
 702         dev = bus_find_device(&ccw_bus_type, NULL, dev_id, match_dev_id);
 703
 704         return dev ? to_ccwdev(dev) : NULL;
 705 }
 706
 707 static void ccw_device_do_unbind_bind(struct ccw_device *cdev)
 708 {
 709         int ret;
 710
 711         if (device_is_registered(&cdev->dev)) {
 712                 device_release_driver(&cdev->dev);
 713                 ret = device_attach(&cdev->dev);
 714                 WARN_ON(ret == -ENODEV);
 715         }
 716 }
 717
 718 static void
 719 ccw_device_release(struct device *dev)
 720 {
 721         struct ccw_device *cdev;
 722
 723         cdev = to_ccwdev(dev);
 724         /* Release reference of parent subchannel. */
 725         put_device(cdev->dev.parent);
 726         kfree(cdev->private);
 727         kfree(cdev);
 728 }
 729
 730 static struct ccw_device * io_subchannel_allocate_dev(struct subchannel *sch)
 731 {
 732         struct ccw_device *cdev;
 733
 734         cdev  = kzalloc(sizeof(*cdev), GFP_KERNEL);
 735         if (cdev) {
 736                 cdev->private = kzalloc(sizeof(struct ccw_device_private),
 737                                         GFP_KERNEL | GFP_DMA);
 738                 if (cdev->private)
 739                         return cdev;
 740         }
 741         kfree(cdev);
 742         return ERR_PTR(-ENOMEM);
 743 }
 744
 745 static void ccw_device_todo(struct work_struct *work);
 746
 747 static int io_subchannel_initialize_dev(struct subchannel *sch,
 748                                         struct ccw_device *cdev)
 749 {
 750         cdev->private->cdev = cdev;
 751         cdev->private->int_class = IOINT_CIO;
 752         atomic_set(&cdev->private->onoff, 0);
 753         cdev->dev.parent = &sch->dev;
 754         cdev->dev.release = ccw_device_release;
 755         INIT_WORK(&cdev->private->todo_work, ccw_device_todo);
 756         cdev->dev.groups = ccwdev_attr_groups;
 757         /* Do first half of device_register. */
 758         device_initialize(&cdev->dev);
 759         if (!get_device(&sch->dev)) {
 760                 /* Release reference from device_initialize(). */
 761                 put_device(&cdev->dev);
 762                 return -ENODEV;
 763         }
 764         cdev->private->flags.initialized = 1;
 765         return 0;
 766 }
 767
 768 static struct ccw_device * io_subchannel_create_ccwdev(struct subchannel *sch)
 769 {
 770         struct ccw_device *cdev;
 771         int ret;
 772
 773         cdev = io_subchannel_allocate_dev(sch);
 774         if (!IS_ERR(cdev)) {
 775                 ret = io_subchannel_initialize_dev(sch, cdev);
 776                 if (ret)
 777                         cdev = ERR_PTR(ret);
 778         }
 779         return cdev;
 780 }
 781
 782 static void io_subchannel_recog(struct ccw_device *, struct subchannel *);
 783
 784 static void sch_create_and_recog_new_device(struct subchannel *sch)
 785 {
 786         struct ccw_device *cdev;
 787
 788         /* Need to allocate a new ccw device. */
 789         cdev = io_subchannel_create_ccwdev(sch);
 790         if (IS_ERR(cdev)) {
 791                 /* OK, we did everything we could... */
 792                 css_sch_device_unregister(sch);
 793                 return;
 794         }
 795         /* Start recognition for the new ccw device. */
 796         io_subchannel_recog(cdev, sch);
 797 }
 798
 799 /*
 800  * Register recognized device.
 801  */
 802 static void io_subchannel_register(struct ccw_device *cdev)
 803 {
 804         struct subchannel *sch;
 805         int ret, adjust_init_count = 1;
 806         unsigned long flags;
 807
 808         sch = to_subchannel(cdev->dev.parent);
 809         /*
 810          * Check if subchannel is still registered. It may have become
 811          * unregistered if a machine check hit us after finishing
 812          * device recognition but before the register work could be
 813          * queued.
 814          */
 815         if (!device_is_registered(&sch->dev))
 816                 goto out_err;
 817         css_update_ssd_info(sch);
 818         /*
 819          * io_subchannel_register() will also be called after device
 820          * recognition has been done for a boxed device (which will already
 821          * be registered). We need to reprobe since we may now have sense id
 822          * information.
 823          */
 824         if (device_is_registered(&cdev->dev)) {
 825                 if (!cdev->drv) {
 826                         ret = device_reprobe(&cdev->dev);
 827                         if (ret)
 828                                 /* We can't do much here. */
 829                                 CIO_MSG_EVENT(0, "device_reprobe() returned"
 830                                               " %d for 0.%x.%04x\n", ret,
 831                                               cdev->private->dev_id.ssid,
 832                                               cdev->private->dev_id.devno);
 833                 }
 834                 adjust_init_count = 0;
 835                 goto out;
 836         }
 837         /*
 838          * Now we know this subchannel will stay, we can throw
 839          * our delayed uevent.
 840          */
 841         dev_set_uevent_suppress(&sch->dev, 0);
 842         kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
 843         /* make it known to the system */
 844         ret = ccw_device_register(cdev);
 845         if (ret) {
 846                 CIO_MSG_EVENT(0, "Could not register ccw dev 0.%x.%04x: %d\n",
 847                               cdev->private->dev_id.ssid,
 848                               cdev->private->dev_id.devno, ret);
 849                 spin_lock_irqsave(sch->lock, flags);
 850                 sch_set_cdev(sch, NULL);
 851                 spin_unlock_irqrestore(sch->lock, flags);
 852                 /* Release initial device reference. */
 853                 put_device(&cdev->dev);
 854                 goto out_err;
 855         }
 856 out:
 857         cdev->private->flags.recog_done = 1;
 858         wake_up(&cdev->private->wait_q);
 859 out_err:
 860         if (adjust_init_count && atomic_dec_and_test(&ccw_device_init_count))
 861                 wake_up(&ccw_device_init_wq);
 862 }
 863
 864 static void ccw_device_call_sch_unregister(struct ccw_device *cdev)
 865 {
 866         struct subchannel *sch;
 867
 868         /* Get subchannel reference for local processing. */
 869         if (!get_device(cdev->dev.parent))
 870                 return;
 871         sch = to_subchannel(cdev->dev.parent);
 872         css_sch_device_unregister(sch);
 873         /* Release subchannel reference for local processing. */
 874         put_device(&sch->dev);
 875 }
 876
 877 /*
 878  * subchannel recognition done. Called from the state machine.
 879  */
 880 void
 881 io_subchannel_recog_done(struct ccw_device *cdev)
 882 {
 883         if (css_init_done == 0) {
 884                 cdev->private->flags.recog_done = 1;
 885                 return;
 886         }
 887         switch (cdev->private->state) {
 888         case DEV_STATE_BOXED:
 889                 /* Device did not respond in time. */
 890         case DEV_STATE_NOT_OPER:
 891                 cdev->private->flags.recog_done = 1;
 892                 /* Remove device found not operational. */
 893                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
 894                 if (atomic_dec_and_test(&ccw_device_init_count))
 895                         wake_up(&ccw_device_init_wq);
 896                 break;
 897         case DEV_STATE_OFFLINE:
 898                 /*
 899                  * We can't register the device in interrupt context so
 900                  * we schedule a work item.
 901                  */
 902                 ccw_device_sched_todo(cdev, CDEV_TODO_REGISTER);
 903                 break;
 904         }
 905 }
 906
 907 static void io_subchannel_recog(struct ccw_device *cdev, struct subchannel *sch)
 908 {
 909         struct ccw_device_private *priv;
 910
 911         cdev->ccwlock = sch->lock;
 912
 913         /* Init private data. */
 914         priv = cdev->private;
 915         priv->dev_id.devno = sch->schib.pmcw.dev;
 916         priv->dev_id.ssid = sch->schid.ssid;
 917         priv->schid = sch->schid;
 918         priv->state = DEV_STATE_NOT_OPER;
 919         INIT_LIST_HEAD(&priv->cmb_list);
 920         init_waitqueue_head(&priv->wait_q);
 921         init_timer(&priv->timer);
 922
 923         /* Increase counter of devices currently in recognition. */
 924         atomic_inc(&ccw_device_init_count);
 925
 926         /* Start async. device sensing. */
 927         spin_lock_irq(sch->lock);
 928         sch_set_cdev(sch, cdev);
 929         ccw_device_recognition(cdev);
 930         spin_unlock_irq(sch->lock);
 931 }
 932
 933 static int ccw_device_move_to_sch(struct ccw_device *cdev,
 934                                   struct subchannel *sch)
 935 {
 936         struct subchannel *old_sch;
 937         int rc, old_enabled = 0;
 938
 939         old_sch = to_subchannel(cdev->dev.parent);
 940         /* Obtain child reference for new parent. */
 941         if (!get_device(&sch->dev))
 942                 return -ENODEV;
 943
 944         if (!sch_is_pseudo_sch(old_sch)) {
 945                 spin_lock_irq(old_sch->lock);
 946                 old_enabled = old_sch->schib.pmcw.ena;
 947                 rc = 0;
 948                 if (old_enabled)
 949                         rc = cio_disable_subchannel(old_sch);
 950                 spin_unlock_irq(old_sch->lock);
 951                 if (rc == -EBUSY) {
 952                         /* Release child reference for new parent. */
 953                         put_device(&sch->dev);
 954                         return rc;
 955                 }
 956         }
 957
 958         mutex_lock(&sch->reg_mutex);
 959         rc = device_move(&cdev->dev, &sch->dev, DPM_ORDER_PARENT_BEFORE_DEV);
 960         mutex_unlock(&sch->reg_mutex);
 961         if (rc) {
 962                 CIO_MSG_EVENT(0, "device_move(0.%x.%04x,0.%x.%04x)=%d\n",
 963                               cdev->private->dev_id.ssid,
 964                               cdev->private->dev_id.devno, sch->schid.ssid,
 965                               sch->schib.pmcw.dev, rc);
 966                 if (old_enabled) {
 967                         /* Try to reenable the old subchannel. */
 968                         spin_lock_irq(old_sch->lock);
 969                         cio_enable_subchannel(old_sch, (u32)(addr_t)old_sch);
 970                         spin_unlock_irq(old_sch->lock);
 971                 }
 972                 /* Release child reference for new parent. */
 973                 put_device(&sch->dev);
 974                 return rc;
 975         }
 976         /* Clean up old subchannel. */
 977         if (!sch_is_pseudo_sch(old_sch)) {
 978                 spin_lock_irq(old_sch->lock);
 979                 sch_set_cdev(old_sch, NULL);
 980                 spin_unlock_irq(old_sch->lock);
 981                 css_schedule_eval(old_sch->schid);
 982         }
 983         /* Release child reference for old parent. */
 984         put_device(&old_sch->dev);
 985         /* Initialize new subchannel. */
 986         spin_lock_irq(sch->lock);
 987         cdev->private->schid = sch->schid;
 988         cdev->ccwlock = sch->lock;
 989         if (!sch_is_pseudo_sch(sch))
 990                 sch_set_cdev(sch, cdev);
 991         spin_unlock_irq(sch->lock);
 992         if (!sch_is_pseudo_sch(sch))
 993                 css_update_ssd_info(sch);
 994         return 0;
 995 }
 996
 997 static int ccw_device_move_to_orph(struct ccw_device *cdev)
 998 {
 999         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1000         struct channel_subsystem *css = to_css(sch->dev.parent);
1001
1002         return ccw_device_move_to_sch(cdev, css->pseudo_subchannel);
1003 }
1004
1005 static void io_subchannel_irq(struct subchannel *sch)
1006 {
1007         struct ccw_device *cdev;
1008
1009         cdev = sch_get_cdev(sch);
1010
1011         CIO_TRACE_EVENT(6, "IRQ");
1012         CIO_TRACE_EVENT(6, dev_name(&sch->dev));
1013         if (cdev)
1014                 dev_fsm_event(cdev, DEV_EVENT_INTERRUPT);
1015         else
1016                 kstat_cpu(smp_processor_id()).irqs[IOINT_CIO]++;
1017 }
1018
1019 void io_subchannel_init_config(struct subchannel *sch)
1020 {
1021         memset(&sch->config, 0, sizeof(sch->config));
1022         sch->config.csense = 1;
1023 }
1024
1025 static void io_subchannel_init_fields(struct subchannel *sch)
1026 {
1027         if (cio_is_console(sch->schid))
1028                 sch->opm = 0xff;
1029         else
1030                 sch->opm = chp_get_sch_opm(sch);
1031         sch->lpm = sch->schib.pmcw.pam & sch->opm;
1032         sch->isc = cio_is_console(sch->schid) ? CONSOLE_ISC : IO_SCH_ISC;
1033
1034         CIO_MSG_EVENT(6, "Detected device %04x on subchannel 0.%x.%04X"
1035                       " - PIM = %02X, PAM = %02X, POM = %02X\n",
1036                       sch->schib.pmcw.dev, sch->schid.ssid,
1037                       sch->schid.sch_no, sch->schib.pmcw.pim,
1038                       sch->schib.pmcw.pam, sch->schib.pmcw.pom);
1039
1040         io_subchannel_init_config(sch);
1041 }
1042
1043 /*
1044  * Note: We always return 0 so that we bind to the device even on error.
1045  * This is needed so that our remove function is called on unregister.
1046  */
1047 static int io_subchannel_probe(struct subchannel *sch)
1048 {
1049         struct io_subchannel_private *io_priv;
1050         struct ccw_device *cdev;
1051         int rc;
1052
1053         if (cio_is_console(sch->schid)) {
1054                 rc = sysfs_create_group(&sch->dev.kobj,
1055                                         &io_subchannel_attr_group);
1056                 if (rc)
1057                         CIO_MSG_EVENT(0, "Failed to create io subchannel "
1058                                       "attributes for subchannel "
1059                                       "0.%x.%04x (rc=%d)\n",
1060                                       sch->schid.ssid, sch->schid.sch_no, rc);
1061                 /*
1062                  * The console subchannel already has an associated ccw_device.
1063                  * Throw the delayed uevent for the subchannel, register
1064                  * the ccw_device and exit.
1065                  */
1066                 dev_set_uevent_suppress(&sch->dev, 0);
1067                 kobject_uevent(&sch->dev.kobj, KOBJ_ADD);
1068                 cdev = sch_get_cdev(sch);
1069                 cdev->dev.groups = ccwdev_attr_groups;
1070                 device_initialize(&cdev->dev);
1071                 cdev->private->flags.initialized = 1;
1072                 ccw_device_register(cdev);
1073                 /*
1074                  * Check if the device is already online. If it is
1075                  * the reference count needs to be corrected since we
1076                  * didn't obtain a reference in ccw_device_set_online.
1077                  */
1078                 if (cdev->private->state != DEV_STATE_NOT_OPER &&
1079                     cdev->private->state != DEV_STATE_OFFLINE &&
1080                     cdev->private->state != DEV_STATE_BOXED)
1081                         get_device(&cdev->dev);
1082                 return 0;
1083         }
1084         io_subchannel_init_fields(sch);
1085         rc = cio_commit_config(sch);
1086         if (rc)
1087                 goto out_schedule;
1088         rc = sysfs_create_group(&sch->dev.kobj,
1089                                 &io_subchannel_attr_group);
1090         if (rc)
1091                 goto out_schedule;
1092         /* Allocate I/O subchannel private data. */
1093         io_priv = kzalloc(sizeof(*io_priv), GFP_KERNEL | GFP_DMA);
1094         if (!io_priv)
1095                 goto out_schedule;
1096
1097         set_io_private(sch, io_priv);
1098         css_schedule_eval(sch->schid);
1099         return 0;
1100
1101 out_schedule:
1102         spin_lock_irq(sch->lock);
1103         css_sched_sch_todo(sch, SCH_TODO_UNREG);
1104         spin_unlock_irq(sch->lock);
1105         return 0;
1106 }
1107
1108 static int
1109 io_subchannel_remove (struct subchannel *sch)
1110 {
1111         struct io_subchannel_private *io_priv = to_io_private(sch);
1112         struct ccw_device *cdev;
1113
1114         cdev = sch_get_cdev(sch);
1115         if (!cdev)
1116                 goto out_free;
1117         io_subchannel_quiesce(sch);
1118         /* Set ccw device to not operational and drop reference. */
1119         spin_lock_irq(cdev->ccwlock);
1120         sch_set_cdev(sch, NULL);
1121         set_io_private(sch, NULL);
1122         cdev->private->state = DEV_STATE_NOT_OPER;
1123         spin_unlock_irq(cdev->ccwlock);
1124         ccw_device_unregister(cdev);
1125 out_free:
1126         kfree(io_priv);
1127         sysfs_remove_group(&sch->dev.kobj, &io_subchannel_attr_group);
1128         return 0;
1129 }
1130
1131 static void io_subchannel_verify(struct subchannel *sch)
1132 {
1133         struct ccw_device *cdev;
1134
1135         cdev = sch_get_cdev(sch);
1136         if (cdev)
1137                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1138 }
1139
1140 static void io_subchannel_terminate_path(struct subchannel *sch, u8 mask)
1141 {
1142         struct ccw_device *cdev;
1143
1144         cdev = sch_get_cdev(sch);
1145         if (!cdev)
1146                 return;
1147         if (cio_update_schib(sch))
1148                 goto err;
1149         /* Check for I/O on path. */
1150         if (scsw_actl(&sch->schib.scsw) == 0 || sch->schib.pmcw.lpum != mask)
1151                 goto out;
1152         if (cdev->private->state == DEV_STATE_ONLINE) {
1153                 ccw_device_kill_io(cdev);
1154                 goto out;
1155         }
1156         if (cio_clear(sch))
1157                 goto err;
1158 out:
1159         /* Trigger path verification. */
1160         dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1161         return;
1162
1163 err:
1164         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1165 }
1166
1167 static int io_subchannel_chp_event(struct subchannel *sch,
1168                                    struct chp_link *link, int event)
1169 {
1170         struct ccw_device *cdev = sch_get_cdev(sch);
1171         int mask;
1172
1173         mask = chp_ssd_get_mask(&sch->ssd_info, link);
1174         if (!mask)
1175                 return 0;
1176         switch (event) {
1177         case CHP_VARY_OFF:
1178                 sch->opm &= ~mask;
1179                 sch->lpm &= ~mask;
1180                 if (cdev)
1181                         cdev->private->path_gone_mask |= mask;
1182                 io_subchannel_terminate_path(sch, mask);
1183                 break;
1184         case CHP_VARY_ON:
1185                 sch->opm |= mask;
1186                 sch->lpm |= mask;
1187                 if (cdev)
1188                         cdev->private->path_new_mask |= mask;
1189                 io_subchannel_verify(sch);
1190                 break;
1191         case CHP_OFFLINE:
1192                 if (cio_update_schib(sch))
1193                         return -ENODEV;
1194                 if (cdev)
1195                         cdev->private->path_gone_mask |= mask;
1196                 io_subchannel_terminate_path(sch, mask);
1197                 break;
1198         case CHP_ONLINE:
1199                 if (cio_update_schib(sch))
1200                         return -ENODEV;
1201                 sch->lpm |= mask & sch->opm;
1202                 if (cdev)
1203                         cdev->private->path_new_mask |= mask;
1204                 io_subchannel_verify(sch);
1205                 break;
1206         }
1207         return 0;
1208 }
1209
1210 static void io_subchannel_quiesce(struct subchannel *sch)
1211 {
1212         struct ccw_device *cdev;
1213         int ret;
1214
1215         spin_lock_irq(sch->lock);
1216         cdev = sch_get_cdev(sch);
1217         if (cio_is_console(sch->schid))
1218                 goto out_unlock;
1219         if (!sch->schib.pmcw.ena)
1220                 goto out_unlock;
1221         ret = cio_disable_subchannel(sch);
1222         if (ret != -EBUSY)
1223                 goto out_unlock;
1224         if (cdev->handler)
1225                 cdev->handler(cdev, cdev->private->intparm, ERR_PTR(-EIO));
1226         while (ret == -EBUSY) {
1227                 cdev->private->state = DEV_STATE_QUIESCE;
1228                 cdev->private->iretry = 255;
1229                 ret = ccw_device_cancel_halt_clear(cdev);
1230                 if (ret == -EBUSY) {
1231                         ccw_device_set_timeout(cdev, HZ/10);
1232                         spin_unlock_irq(sch->lock);
1233                         wait_event(cdev->private->wait_q,
1234                                    cdev->private->state != DEV_STATE_QUIESCE);
1235                         spin_lock_irq(sch->lock);
1236                 }
1237                 ret = cio_disable_subchannel(sch);
1238         }
1239 out_unlock:
1240         spin_unlock_irq(sch->lock);
1241 }
1242
1243 static void io_subchannel_shutdown(struct subchannel *sch)
1244 {
1245         io_subchannel_quiesce(sch);
1246 }
1247
1248 static int device_is_disconnected(struct ccw_device *cdev)
1249 {
1250         if (!cdev)
1251                 return 0;
1252         return (cdev->private->state == DEV_STATE_DISCONNECTED ||
1253                 cdev->private->state == DEV_STATE_DISCONNECTED_SENSE_ID);
1254 }
1255
1256 static int recovery_check(struct device *dev, void *data)
1257 {
1258         struct ccw_device *cdev = to_ccwdev(dev);
1259         int *redo = data;
1260
1261         spin_lock_irq(cdev->ccwlock);
1262         switch (cdev->private->state) {
1263         case DEV_STATE_DISCONNECTED:
1264                 CIO_MSG_EVENT(3, "recovery: trigger 0.%x.%04x\n",
1265                               cdev->private->dev_id.ssid,
1266                               cdev->private->dev_id.devno);
1267                 dev_fsm_event(cdev, DEV_EVENT_VERIFY);
1268                 *redo = 1;
1269                 break;
1270         case DEV_STATE_DISCONNECTED_SENSE_ID:
1271                 *redo = 1;
1272                 break;
1273         }
1274         spin_unlock_irq(cdev->ccwlock);
1275
1276         return 0;
1277 }
1278
1279 static void recovery_work_func(struct work_struct *unused)
1280 {
1281         int redo = 0;
1282
1283         bus_for_each_dev(&ccw_bus_type, NULL, &redo, recovery_check);
1284         if (redo) {
1285                 spin_lock_irq(&recovery_lock);
1286                 if (!timer_pending(&recovery_timer)) {
1287                         if (recovery_phase < ARRAY_SIZE(recovery_delay) - 1)
1288                                 recovery_phase++;
1289                         mod_timer(&recovery_timer, jiffies +
1290                                   recovery_delay[recovery_phase] * HZ);
1291                 }
1292                 spin_unlock_irq(&recovery_lock);
1293         } else
1294                 CIO_MSG_EVENT(4, "recovery: end\n");
1295 }
1296
1297 static DECLARE_WORK(recovery_work, recovery_work_func);
1298
1299 static void recovery_func(unsigned long data)
1300 {
1301         /*
1302          * We can't do our recovery in softirq context and it's not
1303          * performance critical, so we schedule it.
1304          */
1305         schedule_work(&recovery_work);
1306 }
1307
1308 static void ccw_device_schedule_recovery(void)
1309 {
1310         unsigned long flags;
1311
1312         CIO_MSG_EVENT(4, "recovery: schedule\n");
1313         spin_lock_irqsave(&recovery_lock, flags);
1314         if (!timer_pending(&recovery_timer) || (recovery_phase != 0)) {
1315                 recovery_phase = 0;
1316                 mod_timer(&recovery_timer, jiffies + recovery_delay[0] * HZ);
1317         }
1318         spin_unlock_irqrestore(&recovery_lock, flags);
1319 }
1320
1321 static int purge_fn(struct device *dev, void *data)
1322 {
1323         struct ccw_device *cdev = to_ccwdev(dev);
1324         struct ccw_dev_id *id = &cdev->private->dev_id;
1325
1326         spin_lock_irq(cdev->ccwlock);
1327         if (is_blacklisted(id->ssid, id->devno) &&
1328             (cdev->private->state == DEV_STATE_OFFLINE) &&
1329             (atomic_cmpxchg(&cdev->private->onoff, 0, 1) == 0)) {
1330                 CIO_MSG_EVENT(3, "ccw: purging 0.%x.%04x\n", id->ssid,
1331                               id->devno);
1332                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1333                 atomic_set(&cdev->private->onoff, 0);
1334         }
1335         spin_unlock_irq(cdev->ccwlock);
1336         /* Abort loop in case of pending signal. */
1337         if (signal_pending(current))
1338                 return -EINTR;
1339
1340         return 0;
1341 }
1342
1343 /**
1344  * ccw_purge_blacklisted - purge unused, blacklisted devices
1345  *
1346  * Unregister all ccw devices that are offline and on the blacklist.
1347  */
1348 int ccw_purge_blacklisted(void)
1349 {
1350         CIO_MSG_EVENT(2, "ccw: purging blacklisted devices\n");
1351         bus_for_each_dev(&ccw_bus_type, NULL, NULL, purge_fn);
1352         return 0;
1353 }
1354
1355 void ccw_device_set_disconnected(struct ccw_device *cdev)
1356 {
1357         if (!cdev)
1358                 return;
1359         ccw_device_set_timeout(cdev, 0);
1360         cdev->private->flags.fake_irb = 0;
1361         cdev->private->state = DEV_STATE_DISCONNECTED;
1362         if (cdev->online)
1363                 ccw_device_schedule_recovery();
1364 }
1365
1366 void ccw_device_set_notoper(struct ccw_device *cdev)
1367 {
1368         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1369
1370         CIO_TRACE_EVENT(2, "notoper");
1371         CIO_TRACE_EVENT(2, dev_name(&sch->dev));
1372         ccw_device_set_timeout(cdev, 0);
1373         cio_disable_subchannel(sch);
1374         cdev->private->state = DEV_STATE_NOT_OPER;
1375 }
1376
1377 enum io_sch_action {
1378         IO_SCH_UNREG,
1379         IO_SCH_ORPH_UNREG,
1380         IO_SCH_ATTACH,
1381         IO_SCH_UNREG_ATTACH,
1382         IO_SCH_ORPH_ATTACH,
1383         IO_SCH_REPROBE,
1384         IO_SCH_VERIFY,
1385         IO_SCH_DISC,
1386         IO_SCH_NOP,
1387 };
1388
1389 static enum io_sch_action sch_get_action(struct subchannel *sch)
1390 {
1391         struct ccw_device *cdev;
1392
1393         cdev = sch_get_cdev(sch);
1394         if (cio_update_schib(sch)) {
1395                 /* Not operational. */
1396                 if (!cdev)
1397                         return IO_SCH_UNREG;
1398                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1399                         return IO_SCH_UNREG;
1400                 return IO_SCH_ORPH_UNREG;
1401         }
1402         /* Operational. */
1403         if (!cdev)
1404                 return IO_SCH_ATTACH;
1405         if (sch->schib.pmcw.dev != cdev->private->dev_id.devno) {
1406                 if (ccw_device_notify(cdev, CIO_GONE) != NOTIFY_OK)
1407                         return IO_SCH_UNREG_ATTACH;
1408                 return IO_SCH_ORPH_ATTACH;
1409         }
1410         if ((sch->schib.pmcw.pam & sch->opm) == 0) {
1411                 if (ccw_device_notify(cdev, CIO_NO_PATH) != NOTIFY_OK)
1412                         return IO_SCH_UNREG;
1413                 return IO_SCH_DISC;
1414         }
1415         if (device_is_disconnected(cdev))
1416                 return IO_SCH_REPROBE;
1417         if (cdev->online)
1418                 return IO_SCH_VERIFY;
1419         return IO_SCH_NOP;
1420 }
1421
1422 /**
1423  * io_subchannel_sch_event - process subchannel event
1424  * @sch: subchannel
1425  * @process: non-zero if function is called in process context
1426  *
1427  * An unspecified event occurred for this subchannel. Adjust data according
1428  * to the current operational state of the subchannel and device. Return
1429  * zero when the event has been handled sufficiently or -EAGAIN when this
1430  * function should be called again in process context.
1431  */
1432 static int io_subchannel_sch_event(struct subchannel *sch, int process)
1433 {
1434         unsigned long flags;
1435         struct ccw_device *cdev;
1436         struct ccw_dev_id dev_id;
1437         enum io_sch_action action;
1438         int rc = -EAGAIN;
1439
1440         spin_lock_irqsave(sch->lock, flags);
1441         if (!device_is_registered(&sch->dev))
1442                 goto out_unlock;
1443         if (work_pending(&sch->todo_work))
1444                 goto out_unlock;
1445         cdev = sch_get_cdev(sch);
1446         if (cdev && work_pending(&cdev->private->todo_work))
1447                 goto out_unlock;
1448         action = sch_get_action(sch);
1449         CIO_MSG_EVENT(2, "event: sch 0.%x.%04x, process=%d, action=%d\n",
1450                       sch->schid.ssid, sch->schid.sch_no, process,
1451                       action);
1452         /* Perform immediate actions while holding the lock. */
1453         switch (action) {
1454         case IO_SCH_REPROBE:
1455                 /* Trigger device recognition. */
1456                 ccw_device_trigger_reprobe(cdev);
1457                 rc = 0;
1458                 goto out_unlock;
1459         case IO_SCH_VERIFY:
1460                 if (cdev->private->flags.resuming == 1) {
1461                         if (cio_enable_subchannel(sch, (u32)(addr_t)sch)) {
1462                                 ccw_device_set_notoper(cdev);
1463                                 break;
1464                         }
1465                 }
1466                 /* Trigger path verification. */
1467                 io_subchannel_verify(sch);
1468                 rc = 0;
1469                 goto out_unlock;
1470         case IO_SCH_DISC:
1471                 ccw_device_set_disconnected(cdev);
1472                 rc = 0;
1473                 goto out_unlock;
1474         case IO_SCH_ORPH_UNREG:
1475         case IO_SCH_ORPH_ATTACH:
1476                 ccw_device_set_disconnected(cdev);
1477                 break;
1478         case IO_SCH_UNREG_ATTACH:
1479         case IO_SCH_UNREG:
1480                 if (!cdev)
1481                         break;
1482                 if (cdev->private->state == DEV_STATE_SENSE_ID) {
1483                         /*
1484                          * Note: delayed work triggered by this event
1485                          * and repeated calls to sch_event are synchronized
1486                          * by the above check for work_pending(cdev).
1487                          */
1488                         dev_fsm_event(cdev, DEV_EVENT_NOTOPER);
1489                 } else
1490                         ccw_device_set_notoper(cdev);
1491                 break;
1492         case IO_SCH_NOP:
1493                 rc = 0;
1494                 goto out_unlock;
1495         default:
1496                 break;
1497         }
1498         spin_unlock_irqrestore(sch->lock, flags);
1499         /* All other actions require process context. */
1500         if (!process)
1501                 goto out;
1502         /* Handle attached ccw device. */
1503         switch (action) {
1504         case IO_SCH_ORPH_UNREG:
1505         case IO_SCH_ORPH_ATTACH:
1506                 /* Move ccw device to orphanage. */
1507                 rc = ccw_device_move_to_orph(cdev);
1508                 if (rc)
1509                         goto out;
1510                 break;
1511         case IO_SCH_UNREG_ATTACH:
1512                 if (cdev->private->flags.resuming) {
1513                         /* Device will be handled later. */
1514                         rc = 0;
1515                         goto out;
1516                 }
1517                 /* Unregister ccw device. */
1518                 ccw_device_unregister(cdev);
1519                 break;
1520         default:
1521                 break;
1522         }
1523         /* Handle subchannel. */
1524         switch (action) {
1525         case IO_SCH_ORPH_UNREG:
1526         case IO_SCH_UNREG:
1527                 if (!cdev || !cdev->private->flags.resuming)
1528                         css_sch_device_unregister(sch);
1529                 break;
1530         case IO_SCH_ORPH_ATTACH:
1531         case IO_SCH_UNREG_ATTACH:
1532         case IO_SCH_ATTACH:
1533                 dev_id.ssid = sch->schid.ssid;
1534                 dev_id.devno = sch->schib.pmcw.dev;
1535                 cdev = get_ccwdev_by_dev_id(&dev_id);
1536                 if (!cdev) {
1537                         sch_create_and_recog_new_device(sch);
1538                         break;
1539                 }
1540                 rc = ccw_device_move_to_sch(cdev, sch);
1541                 if (rc) {
1542                         /* Release reference from get_ccwdev_by_dev_id() */
1543                         put_device(&cdev->dev);
1544                         goto out;
1545                 }
1546                 spin_lock_irqsave(sch->lock, flags);
1547                 ccw_device_trigger_reprobe(cdev);
1548                 spin_unlock_irqrestore(sch->lock, flags);
1549                 /* Release reference from get_ccwdev_by_dev_id() */
1550                 put_device(&cdev->dev);
1551                 break;
1552         default:
1553                 break;
1554         }
1555         return 0;
1556
1557 out_unlock:
1558         spin_unlock_irqrestore(sch->lock, flags);
1559 out:
1560         return rc;
1561 }
1562
1563 #ifdef CONFIG_CCW_CONSOLE
1564 static struct ccw_device console_cdev;
1565 static struct ccw_device_private console_private;
1566 static int console_cdev_in_use;
1567
1568 static DEFINE_SPINLOCK(ccw_console_lock);
1569
1570 spinlock_t * cio_get_console_lock(void)
1571 {
1572         return &ccw_console_lock;
1573 }
1574
1575 static int ccw_device_console_enable(struct ccw_device *cdev,
1576                                      struct subchannel *sch)
1577 {
1578         struct io_subchannel_private *io_priv = cio_get_console_priv();
1579         int rc;
1580
1581         /* Attach subchannel private data. */
1582         memset(io_priv, 0, sizeof(*io_priv));
1583         set_io_private(sch, io_priv);
1584         io_subchannel_init_fields(sch);
1585         rc = cio_commit_config(sch);
1586         if (rc)
1587                 return rc;
1588         sch->driver = &io_subchannel_driver;
1589         /* Initialize the ccw_device structure. */
1590         cdev->dev.parent= &sch->dev;
1591         sch_set_cdev(sch, cdev);
1592         io_subchannel_recog(cdev, sch);
1593         /* Now wait for the async. recognition to come to an end. */
1594         spin_lock_irq(cdev->ccwlock);
1595         while (!dev_fsm_final_state(cdev))
1596                 wait_cons_dev();
1597         rc = -EIO;
1598         if (cdev->private->state != DEV_STATE_OFFLINE)
1599                 goto out_unlock;
1600         ccw_device_online(cdev);
1601         while (!dev_fsm_final_state(cdev))
1602                 wait_cons_dev();
1603         if (cdev->private->state != DEV_STATE_ONLINE)
1604                 goto out_unlock;
1605         rc = 0;
1606 out_unlock:
1607         spin_unlock_irq(cdev->ccwlock);
1608         return rc;
1609 }
1610
1611 struct ccw_device *
1612 ccw_device_probe_console(void)
1613 {
1614         struct subchannel *sch;
1615         int ret;
1616
1617         if (xchg(&console_cdev_in_use, 1) != 0)
1618                 return ERR_PTR(-EBUSY);
1619         sch = cio_probe_console();
1620         if (IS_ERR(sch)) {
1621                 console_cdev_in_use = 0;
1622                 return (void *) sch;
1623         }
1624         memset(&console_cdev, 0, sizeof(struct ccw_device));
1625         memset(&console_private, 0, sizeof(struct ccw_device_private));
1626         console_cdev.private = &console_private;
1627         console_private.cdev = &console_cdev;
1628         console_private.int_class = IOINT_CIO;
1629         ret = ccw_device_console_enable(&console_cdev, sch);
1630         if (ret) {
1631                 cio_release_console();
1632                 console_cdev_in_use = 0;
1633                 return ERR_PTR(ret);
1634         }
1635         console_cdev.online = 1;
1636         return &console_cdev;
1637 }
1638
1639 static int ccw_device_pm_restore(struct device *dev);
1640
1641 int ccw_device_force_console(void)
1642 {
1643         if (!console_cdev_in_use)
1644                 return -ENODEV;
1645         return ccw_device_pm_restore(&console_cdev.dev);
1646 }
1647 EXPORT_SYMBOL_GPL(ccw_device_force_console);
1648 #endif
1649
1650 /*
1651  * get ccw_device matching the busid, but only if owned by cdrv
1652  */
1653 static int
1654 __ccwdev_check_busid(struct device *dev, void *id)
1655 {
1656         char *bus_id;
1657
1658         bus_id = id;
1659
1660         return (strcmp(bus_id, dev_name(dev)) == 0);
1661 }
1662
1663
1664 /**
1665  * get_ccwdev_by_busid() - obtain device from a bus id
1666  * @cdrv: driver the device is owned by
1667  * @bus_id: bus id of the device to be searched
1668  *
1669  * This function searches all devices owned by @cdrv for a device with a bus
1670  * id matching @bus_id.
1671  * Returns:
1672  *  If a match is found, its reference count of the found device is increased
1673  *  and it is returned; else %NULL is returned.
1674  */
1675 struct ccw_device *get_ccwdev_by_busid(struct ccw_driver *cdrv,
1676                                        const char *bus_id)
1677 {
1678         struct device *dev;
1679         struct device_driver *drv;
1680
1681         drv = get_driver(&cdrv->driver);
1682         if (!drv)
1683                 return NULL;
1684
1685         dev = driver_find_device(drv, NULL, (void *)bus_id,
1686                                  __ccwdev_check_busid);
1687         put_driver(drv);
1688
1689         return dev ? to_ccwdev(dev) : NULL;
1690 }
1691
1692 /************************** device driver handling ************************/
1693
1694 /* This is the implementation of the ccw_driver class. The probe, remove
1695  * and release methods are initially very similar to the device_driver
1696  * implementations, with the difference that they have ccw_device
1697  * arguments.
1698  *
1699  * A ccw driver also contains the information that is needed for
1700  * device matching.
1701  */
1702 static int
1703 ccw_device_probe (struct device *dev)
1704 {
1705         struct ccw_device *cdev = to_ccwdev(dev);
1706         struct ccw_driver *cdrv = to_ccwdrv(dev->driver);
1707         int ret;
1708
1709         cdev->drv = cdrv; /* to let the driver call _set_online */
1710         /* Note: we interpret class 0 in this context as an uninitialized
1711          * field since it translates to a non-I/O interrupt class. */
1712         if (cdrv->int_class != 0)
1713                 cdev->private->int_class = cdrv->int_class;
1714         else
1715                 cdev->private->int_class = IOINT_CIO;
1716
1717         ret = cdrv->probe ? cdrv->probe(cdev) : -ENODEV;
1718
1719         if (ret) {
1720                 cdev->drv = NULL;
1721                 cdev->private->int_class = IOINT_CIO;
1722                 return ret;
1723         }
1724
1725         return 0;
1726 }
1727
1728 static int
1729 ccw_device_remove (struct device *dev)
1730 {
1731         struct ccw_device *cdev = to_ccwdev(dev);
1732         struct ccw_driver *cdrv = cdev->drv;
1733         int ret;
1734
1735         if (cdrv->remove)
1736                 cdrv->remove(cdev);
1737         if (cdev->online) {
1738                 cdev->online = 0;
1739                 spin_lock_irq(cdev->ccwlock);
1740                 ret = ccw_device_offline(cdev);
1741                 spin_unlock_irq(cdev->ccwlock);
1742                 if (ret == 0)
1743                         wait_event(cdev->private->wait_q,
1744                                    dev_fsm_final_state(cdev));
1745                 else
1746                         CIO_MSG_EVENT(0, "ccw_device_offline returned %d, "
1747                                       "device 0.%x.%04x\n",
1748                                       ret, cdev->private->dev_id.ssid,
1749                                       cdev->private->dev_id.devno);
1750                 /* Give up reference obtained in ccw_device_set_online(). */
1751                 put_device(&cdev->dev);
1752         }
1753         ccw_device_set_timeout(cdev, 0);
1754         cdev->drv = NULL;
1755         cdev->private->int_class = IOINT_CIO;
1756         return 0;
1757 }
1758
1759 static void ccw_device_shutdown(struct device *dev)
1760 {
1761         struct ccw_device *cdev;
1762
1763         cdev = to_ccwdev(dev);
1764         if (cdev->drv && cdev->drv->shutdown)
1765                 cdev->drv->shutdown(cdev);
1766         disable_cmf(cdev);
1767 }
1768
1769 static int ccw_device_pm_prepare(struct device *dev)
1770 {
1771         struct ccw_device *cdev = to_ccwdev(dev);
1772
1773         if (work_pending(&cdev->private->todo_work))
1774                 return -EAGAIN;
1775         /* Fail while device is being set online/offline. */
1776         if (atomic_read(&cdev->private->onoff))
1777                 return -EAGAIN;
1778
1779         if (cdev->online && cdev->drv && cdev->drv->prepare)
1780                 return cdev->drv->prepare(cdev);
1781
1782         return 0;
1783 }
1784
1785 static void ccw_device_pm_complete(struct device *dev)
1786 {
1787         struct ccw_device *cdev = to_ccwdev(dev);
1788
1789         if (cdev->online && cdev->drv && cdev->drv->complete)
1790                 cdev->drv->complete(cdev);
1791 }
1792
1793 static int ccw_device_pm_freeze(struct device *dev)
1794 {
1795         struct ccw_device *cdev = to_ccwdev(dev);
1796         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1797         int ret, cm_enabled;
1798
1799         /* Fail suspend while device is in transistional state. */
1800         if (!dev_fsm_final_state(cdev))
1801                 return -EAGAIN;
1802         if (!cdev->online)
1803                 return 0;
1804         if (cdev->drv && cdev->drv->freeze) {
1805                 ret = cdev->drv->freeze(cdev);
1806                 if (ret)
1807                         return ret;
1808         }
1809
1810         spin_lock_irq(sch->lock);
1811         cm_enabled = cdev->private->cmb != NULL;
1812         spin_unlock_irq(sch->lock);
1813         if (cm_enabled) {
1814                 /* Don't have the css write on memory. */
1815                 ret = ccw_set_cmf(cdev, 0);
1816                 if (ret)
1817                         return ret;
1818         }
1819         /* From here on, disallow device driver I/O. */
1820         spin_lock_irq(sch->lock);
1821         ret = cio_disable_subchannel(sch);
1822         spin_unlock_irq(sch->lock);
1823
1824         return ret;
1825 }
1826
1827 static int ccw_device_pm_thaw(struct device *dev)
1828 {
1829         struct ccw_device *cdev = to_ccwdev(dev);
1830         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1831         int ret, cm_enabled;
1832
1833         if (!cdev->online)
1834                 return 0;
1835
1836         spin_lock_irq(sch->lock);
1837         /* Allow device driver I/O again. */
1838         ret = cio_enable_subchannel(sch, (u32)(addr_t)sch);
1839         cm_enabled = cdev->private->cmb != NULL;
1840         spin_unlock_irq(sch->lock);
1841         if (ret)
1842                 return ret;
1843
1844         if (cm_enabled) {
1845                 ret = ccw_set_cmf(cdev, 1);
1846                 if (ret)
1847                         return ret;
1848         }
1849
1850         if (cdev->drv && cdev->drv->thaw)
1851                 ret = cdev->drv->thaw(cdev);
1852
1853         return ret;
1854 }
1855
1856 static void __ccw_device_pm_restore(struct ccw_device *cdev)
1857 {
1858         struct subchannel *sch = to_subchannel(cdev->dev.parent);
1859
1860         spin_lock_irq(sch->lock);
1861         if (cio_is_console(sch->schid)) {
1862                 cio_enable_subchannel(sch, (u32)(addr_t)sch);
1863                 goto out_unlock;
1864         }
1865         /*
1866          * While we were sleeping, devices may have gone or become
1867          * available again. Kick re-detection.
1868          */
1869         cdev->private->flags.resuming = 1;
1870         cdev->private->path_new_mask = LPM_ANYPATH;
1871         css_sched_sch_todo(sch, SCH_TODO_EVAL);
1872         spin_unlock_irq(sch->lock);
1873         css_wait_for_slow_path();
1874
1875         /* cdev may have been moved to a different subchannel. */
1876         sch = to_subchannel(cdev->dev.parent);
1877         spin_lock_irq(sch->lock);
1878         if (cdev->private->state != DEV_STATE_ONLINE &&
1879             cdev->private->state != DEV_STATE_OFFLINE)
1880                 goto out_unlock;
1881
1882         ccw_device_recognition(cdev);
1883         spin_unlock_irq(sch->lock);
1884         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev) ||
1885                    cdev->private->state == DEV_STATE_DISCONNECTED);
1886         spin_lock_irq(sch->lock);
1887
1888 out_unlock:
1889         cdev->private->flags.resuming = 0;
1890         spin_unlock_irq(sch->lock);
1891 }
1892
1893 static int resume_handle_boxed(struct ccw_device *cdev)
1894 {
1895         cdev->private->state = DEV_STATE_BOXED;
1896         if (ccw_device_notify(cdev, CIO_BOXED) == NOTIFY_OK)
1897                 return 0;
1898         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1899         return -ENODEV;
1900 }
1901
1902 static int resume_handle_disc(struct ccw_device *cdev)
1903 {
1904         cdev->private->state = DEV_STATE_DISCONNECTED;
1905         if (ccw_device_notify(cdev, CIO_GONE) == NOTIFY_OK)
1906                 return 0;
1907         ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1908         return -ENODEV;
1909 }
1910
1911 static int ccw_device_pm_restore(struct device *dev)
1912 {
1913         struct ccw_device *cdev = to_ccwdev(dev);
1914         struct subchannel *sch;
1915         int ret = 0;
1916
1917         __ccw_device_pm_restore(cdev);
1918         sch = to_subchannel(cdev->dev.parent);
1919         spin_lock_irq(sch->lock);
1920         if (cio_is_console(sch->schid))
1921                 goto out_restore;
1922
1923         /* check recognition results */
1924         switch (cdev->private->state) {
1925         case DEV_STATE_OFFLINE:
1926         case DEV_STATE_ONLINE:
1927                 cdev->private->flags.donotify = 0;
1928                 break;
1929         case DEV_STATE_BOXED:
1930                 ret = resume_handle_boxed(cdev);
1931                 if (ret)
1932                         goto out_unlock;
1933                 goto out_restore;
1934         default:
1935                 ret = resume_handle_disc(cdev);
1936                 if (ret)
1937                         goto out_unlock;
1938                 goto out_restore;
1939         }
1940         /* check if the device type has changed */
1941         if (!ccw_device_test_sense_data(cdev)) {
1942                 ccw_device_update_sense_data(cdev);
1943                 ccw_device_sched_todo(cdev, CDEV_TODO_REBIND);
1944                 ret = -ENODEV;
1945                 goto out_unlock;
1946         }
1947         if (!cdev->online)
1948                 goto out_unlock;
1949
1950         if (ccw_device_online(cdev)) {
1951                 ret = resume_handle_disc(cdev);
1952                 if (ret)
1953                         goto out_unlock;
1954                 goto out_restore;
1955         }
1956         spin_unlock_irq(sch->lock);
1957         wait_event(cdev->private->wait_q, dev_fsm_final_state(cdev));
1958         spin_lock_irq(sch->lock);
1959
1960         if (ccw_device_notify(cdev, CIO_OPER) == NOTIFY_BAD) {
1961                 ccw_device_sched_todo(cdev, CDEV_TODO_UNREG);
1962                 ret = -ENODEV;
1963                 goto out_unlock;
1964         }
1965
1966         /* reenable cmf, if needed */
1967         if (cdev->private->cmb) {
1968                 spin_unlock_irq(sch->lock);
1969                 ret = ccw_set_cmf(cdev, 1);
1970                 spin_lock_irq(sch->lock);
1971                 if (ret) {
1972                         CIO_MSG_EVENT(2, "resume: cdev 0.%x.%04x: cmf failed "
1973                                       "(rc=%d)\n", cdev->private->dev_id.ssid,
1974                                       cdev->private->dev_id.devno, ret);
1975                         ret = 0;
1976                 }
1977         }
1978
1979 out_restore:
1980         spin_unlock_irq(sch->lock);
1981         if (cdev->online && cdev->drv && cdev->drv->restore)
1982                 ret = cdev->drv->restore(cdev);
1983         return ret;
1984
1985 out_unlock:
1986         spin_unlock_irq(sch->lock);
1987         return ret;
1988 }
1989
1990 static const struct dev_pm_ops ccw_pm_ops = {
1991         .prepare = ccw_device_pm_prepare,
1992         .complete = ccw_device_pm_complete,
1993         .freeze = ccw_device_pm_freeze,
1994         .thaw = ccw_device_pm_thaw,
1995         .restore = ccw_device_pm_restore,
1996 };
1997
1998 static struct bus_type ccw_bus_type = {
1999         .name   = "ccw",
2000         .match  = ccw_bus_match,
2001         .uevent = ccw_uevent,
2002         .probe  = ccw_device_probe,
2003         .remove = ccw_device_remove,
2004         .shutdown = ccw_device_shutdown,
2005         .pm = &ccw_pm_ops,
2006 };
2007
2008 /**
2009  * ccw_driver_register() - register a ccw driver
2010  * @cdriver: driver to be registered
2011  *
2012  * This function is mainly a wrapper around driver_register().
2013  * Returns:
2014  *   %0 on success and a negative error value on failure.
2015  */
2016 int ccw_driver_register(struct ccw_driver *cdriver)
2017 {
2018         struct device_driver *drv = &cdriver->driver;
2019
2020         drv->bus = &ccw_bus_type;
2021
2022         return driver_register(drv);
2023 }
2024
2025 /**
2026  * ccw_driver_unregister() - deregister a ccw driver
2027  * @cdriver: driver to be deregistered
2028  *
2029  * This function is mainly a wrapper around driver_unregister().
2030  */
2031 void ccw_driver_unregister(struct ccw_driver *cdriver)
2032 {
2033         driver_unregister(&cdriver->driver);
2034 }
2035
2036 /* Helper func for qdio. */
2037 struct subchannel_id
2038 ccw_device_get_subchannel_id(struct ccw_device *cdev)
2039 {
2040         struct subchannel *sch;
2041
2042         sch = to_subchannel(cdev->dev.parent);
2043         return sch->schid;
2044 }
2045
2046 static void ccw_device_todo(struct work_struct *work)
2047 {
2048         struct ccw_device_private *priv;
2049         struct ccw_device *cdev;
2050         struct subchannel *sch;
2051         enum cdev_todo todo;
2052
2053         priv = container_of(work, struct ccw_device_private, todo_work);
2054         cdev = priv->cdev;
2055         sch = to_subchannel(cdev->dev.parent);
2056         /* Find out todo. */
2057         spin_lock_irq(cdev->ccwlock);
2058         todo = priv->todo;
2059         priv->todo = CDEV_TODO_NOTHING;
2060         CIO_MSG_EVENT(4, "cdev_todo: cdev=0.%x.%04x todo=%d\n",
2061                       priv->dev_id.ssid, priv->dev_id.devno, todo);
2062         spin_unlock_irq(cdev->ccwlock);
2063         /* Perform todo. */
2064         switch (todo) {
2065         case CDEV_TODO_ENABLE_CMF:
2066                 cmf_reenable(cdev);
2067                 break;
2068         case CDEV_TODO_REBIND:
2069                 ccw_device_do_unbind_bind(cdev);
2070                 break;
2071         case CDEV_TODO_REGISTER:
2072                 io_subchannel_register(cdev);
2073                 break;
2074         case CDEV_TODO_UNREG_EVAL:
2075                 if (!sch_is_pseudo_sch(sch))
2076                         css_schedule_eval(sch->schid);
2077                 /* fall-through */
2078         case CDEV_TODO_UNREG:
2079                 if (sch_is_pseudo_sch(sch))
2080                         ccw_device_unregister(cdev);
2081                 else
2082                         ccw_device_call_sch_unregister(cdev);
2083                 break;
2084         default:
2085                 break;
2086         }
2087         /* Release workqueue ref. */
2088         put_device(&cdev->dev);
2089 }
2090
2091 /**
2092  * ccw_device_sched_todo - schedule ccw device operation
2093  * @cdev: ccw device
2094  * @todo: todo
2095  *
2096  * Schedule the operation identified by @todo to be performed on the slow path
2097  * workqueue. Do nothing if another operation with higher priority is already
2098  * scheduled. Needs to be called with ccwdev lock held.
2099  */
2100 void ccw_device_sched_todo(struct ccw_device *cdev, enum cdev_todo todo)
2101 {
2102         CIO_MSG_EVENT(4, "cdev_todo: sched cdev=0.%x.%04x todo=%d\n",
2103                       cdev->private->dev_id.ssid, cdev->private->dev_id.devno,
2104                       todo);
2105         if (cdev->private->todo >= todo)
2106                 return;
2107         cdev->private->todo = todo;
2108         /* Get workqueue ref. */
2109         if (!get_device(&cdev->dev))
2110                 return;
2111         if (!queue_work(cio_work_q, &cdev->private->todo_work)) {
2112                 /* Already queued, release workqueue ref. */
2113                 put_device(&cdev->dev);
2114         }
2115 }
2116
2117 /**
2118  * ccw_device_siosl() - initiate logging
2119  * @cdev: ccw device
2120  *
2121  * This function is used to invoke model-dependent logging within the channel
2122  * subsystem.
2123  */
2124 int ccw_device_siosl(struct ccw_device *cdev)
2125 {
2126         struct subchannel *sch = to_subchannel(cdev->dev.parent);
2127
2128         return chsc_siosl(sch->schid);
2129 }
2130 EXPORT_SYMBOL_GPL(ccw_device_siosl);
2131
2132 MODULE_LICENSE("GPL");
2133 EXPORT_SYMBOL(ccw_device_set_online);
2134 EXPORT_SYMBOL(ccw_device_set_offline);
2135 EXPORT_SYMBOL(ccw_driver_register);
2136 EXPORT_SYMBOL(ccw_driver_unregister);
2137 EXPORT_SYMBOL(get_ccwdev_by_busid);
2138 EXPORT_SYMBOL_GPL(ccw_device_get_subchannel_id);