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   1 /*
   2  * zfcp device driver
   3  *
   4  * Module interface and handling of zfcp data structures.
   5  *
   6  * Copyright IBM Corporation 2002, 2008
   7  */
   8
   9 /*
  10  * Driver authors:
  11  *            Martin Peschke (originator of the driver)
  12  *            Raimund Schroeder
  13  *            Aron Zeh
  14  *            Wolfgang Taphorn
  15  *            Stefan Bader
  16  *            Heiko Carstens (kernel 2.6 port of the driver)
  17  *            Andreas Herrmann
  18  *            Maxim Shchetynin
  19  *            Volker Sameske
  20  *            Ralph Wuerthner
  21  *            Michael Loehr
  22  *            Swen Schillig
  23  *            Christof Schmitt
  24  *            Martin Petermann
  25  *            Sven Schuetz
  26  */
  27
  28 #include <linux/miscdevice.h>
  29 #include "zfcp_ext.h"
  30
  31 static char *device;
  32
  33 MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
  34 MODULE_DESCRIPTION("FCP HBA driver");
  35 MODULE_LICENSE("GPL");
  36
  37 module_param(device, charp, 0400);
  38 MODULE_PARM_DESC(device, "specify initial device");
  39
  40 static int zfcp_reqlist_alloc(struct zfcp_adapter *adapter)
  41 {
  42         int idx;
  43
  44         adapter->req_list = kcalloc(REQUEST_LIST_SIZE, sizeof(struct list_head),
  45                                     GFP_KERNEL);
  46         if (!adapter->req_list)
  47                 return -ENOMEM;
  48
  49         for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
  50                 INIT_LIST_HEAD(&adapter->req_list[idx]);
  51         return 0;
  52 }
  53
  54 /**
  55  * zfcp_reqlist_isempty - is the request list empty
  56  * @adapter: pointer to struct zfcp_adapter
  57  *
  58  * Returns: true if list is empty, false otherwise
  59  */
  60 int zfcp_reqlist_isempty(struct zfcp_adapter *adapter)
  61 {
  62         unsigned int idx;
  63
  64         for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
  65                 if (!list_empty(&adapter->req_list[idx]))
  66                         return 0;
  67         return 1;
  68 }
  69
  70 static int __init zfcp_device_setup(char *devstr)
  71 {
  72         char *token;
  73         char *str;
  74
  75         if (!devstr)
  76                 return 0;
  77
  78         /* duplicate devstr and keep the original for sysfs presentation*/
  79         str = kmalloc(strlen(devstr) + 1, GFP_KERNEL);
  80         if (!str)
  81                 return 0;
  82
  83         strcpy(str, devstr);
  84
  85         token = strsep(&str, ",");
  86         if (!token || strlen(token) >= BUS_ID_SIZE)
  87                 goto err_out;
  88         strncpy(zfcp_data.init_busid, token, BUS_ID_SIZE);
  89
  90         token = strsep(&str, ",");
  91         if (!token || strict_strtoull(token, 0,
  92                                 (unsigned long long *) &zfcp_data.init_wwpn))
  93                 goto err_out;
  94
  95         token = strsep(&str, ",");
  96         if (!token || strict_strtoull(token, 0,
  97                                 (unsigned long long *) &zfcp_data.init_fcp_lun))
  98                 goto err_out;
  99
 100         kfree(str);
 101         return 1;
 102
 103  err_out:
 104         kfree(str);
 105         pr_err("zfcp: %s is not a valid SCSI device\n", devstr);
 106         return 0;
 107 }
 108
 109 static void __init zfcp_init_device_configure(void)
 110 {
 111         struct zfcp_adapter *adapter;
 112         struct zfcp_port *port;
 113         struct zfcp_unit *unit;
 114
 115         down(&zfcp_data.config_sema);
 116         read_lock_irq(&zfcp_data.config_lock);
 117         adapter = zfcp_get_adapter_by_busid(zfcp_data.init_busid);
 118         if (adapter)
 119                 zfcp_adapter_get(adapter);
 120         read_unlock_irq(&zfcp_data.config_lock);
 121
 122         if (!adapter)
 123                 goto out_adapter;
 124         port = zfcp_port_enqueue(adapter, zfcp_data.init_wwpn, 0, 0);
 125         if (IS_ERR(port))
 126                 goto out_port;
 127         unit = zfcp_unit_enqueue(port, zfcp_data.init_fcp_lun);
 128         if (IS_ERR(unit))
 129                 goto out_unit;
 130         up(&zfcp_data.config_sema);
 131         ccw_device_set_online(adapter->ccw_device);
 132         zfcp_erp_wait(adapter);
 133         down(&zfcp_data.config_sema);
 134         zfcp_unit_put(unit);
 135 out_unit:
 136         zfcp_port_put(port);
 137 out_port:
 138         zfcp_adapter_put(adapter);
 139 out_adapter:
 140         up(&zfcp_data.config_sema);
 141         return;
 142 }
 143
 144 static struct kmem_cache *zfcp_cache_create(int size, char *name)
 145 {
 146         int align = 1;
 147         while ((size - align) > 0)
 148                 align <<= 1;
 149         return kmem_cache_create(name , size, align, 0, NULL);
 150 }
 151
 152 static int __init zfcp_module_init(void)
 153 {
 154         int retval = -ENOMEM;
 155
 156         zfcp_data.fsf_req_qtcb_cache = zfcp_cache_create(
 157                         sizeof(struct zfcp_fsf_req_qtcb), "zfcp_fsf");
 158         if (!zfcp_data.fsf_req_qtcb_cache)
 159                 goto out;
 160
 161         zfcp_data.sr_buffer_cache = zfcp_cache_create(
 162                         sizeof(struct fsf_status_read_buffer), "zfcp_sr");
 163         if (!zfcp_data.sr_buffer_cache)
 164                 goto out_sr_cache;
 165
 166         zfcp_data.gid_pn_cache = zfcp_cache_create(
 167                         sizeof(struct zfcp_gid_pn_data), "zfcp_gid");
 168         if (!zfcp_data.gid_pn_cache)
 169                 goto out_gid_cache;
 170
 171         zfcp_data.work_queue = create_singlethread_workqueue("zfcp_wq");
 172
 173         INIT_LIST_HEAD(&zfcp_data.adapter_list_head);
 174         sema_init(&zfcp_data.config_sema, 1);
 175         rwlock_init(&zfcp_data.config_lock);
 176
 177         zfcp_data.scsi_transport_template =
 178                 fc_attach_transport(&zfcp_transport_functions);
 179         if (!zfcp_data.scsi_transport_template)
 180                 goto out_transport;
 181
 182         retval = misc_register(&zfcp_cfdc_misc);
 183         if (retval) {
 184                 pr_err("zfcp: Registering the misc device zfcp_cfdc failed\n");
 185                 goto out_misc;
 186         }
 187
 188         retval = zfcp_ccw_register();
 189         if (retval) {
 190                 pr_err("zfcp: The zfcp device driver could not register with "
 191                        "the common I/O layer\n");
 192                 goto out_ccw_register;
 193         }
 194
 195         if (zfcp_device_setup(device))
 196                 zfcp_init_device_configure();
 197
 198         goto out;
 199
 200 out_ccw_register:
 201         misc_deregister(&zfcp_cfdc_misc);
 202 out_misc:
 203         fc_release_transport(zfcp_data.scsi_transport_template);
 204 out_transport:
 205         kmem_cache_destroy(zfcp_data.gid_pn_cache);
 206 out_gid_cache:
 207         kmem_cache_destroy(zfcp_data.sr_buffer_cache);
 208 out_sr_cache:
 209         kmem_cache_destroy(zfcp_data.fsf_req_qtcb_cache);
 210 out:
 211         return retval;
 212 }
 213
 214 module_init(zfcp_module_init);
 215
 216 /**
 217  * zfcp_get_unit_by_lun - find unit in unit list of port by FCP LUN
 218  * @port: pointer to port to search for unit
 219  * @fcp_lun: FCP LUN to search for
 220  *
 221  * Returns: pointer to zfcp_unit or NULL
 222  */
 223 struct zfcp_unit *zfcp_get_unit_by_lun(struct zfcp_port *port, u64 fcp_lun)
 224 {
 225         struct zfcp_unit *unit;
 226
 227         list_for_each_entry(unit, &port->unit_list_head, list)
 228                 if ((unit->fcp_lun == fcp_lun) &&
 229                     !(atomic_read(&unit->status) & ZFCP_STATUS_COMMON_REMOVE))
 230                     return unit;
 231         return NULL;
 232 }
 233
 234 /**
 235  * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
 236  * @adapter: pointer to adapter to search for port
 237  * @wwpn: wwpn to search for
 238  *
 239  * Returns: pointer to zfcp_port or NULL
 240  */
 241 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
 242                                         u64 wwpn)
 243 {
 244         struct zfcp_port *port;
 245
 246         list_for_each_entry(port, &adapter->port_list_head, list)
 247                 if ((port->wwpn == wwpn) && !(atomic_read(&port->status) &
 248                       (ZFCP_STATUS_PORT_NO_WWPN | ZFCP_STATUS_COMMON_REMOVE)))
 249                         return port;
 250         return NULL;
 251 }
 252
 253 static void zfcp_sysfs_unit_release(struct device *dev)
 254 {
 255         kfree(container_of(dev, struct zfcp_unit, sysfs_device));
 256 }
 257
 258 /**
 259  * zfcp_unit_enqueue - enqueue unit to unit list of a port.
 260  * @port: pointer to port where unit is added
 261  * @fcp_lun: FCP LUN of unit to be enqueued
 262  * Returns: pointer to enqueued unit on success, ERR_PTR on error
 263  * Locks: config_sema must be held to serialize changes to the unit list
 264  *
 265  * Sets up some unit internal structures and creates sysfs entry.
 266  */
 267 struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
 268 {
 269         struct zfcp_unit *unit;
 270
 271         unit = kzalloc(sizeof(struct zfcp_unit), GFP_KERNEL);
 272         if (!unit)
 273                 return ERR_PTR(-ENOMEM);
 274
 275         atomic_set(&unit->refcount, 0);
 276         init_waitqueue_head(&unit->remove_wq);
 277
 278         unit->port = port;
 279         unit->fcp_lun = fcp_lun;
 280
 281         snprintf(unit->sysfs_device.bus_id, BUS_ID_SIZE, "0x%016llx",
 282                  (unsigned long long) fcp_lun);
 283         unit->sysfs_device.parent = &port->sysfs_device;
 284         unit->sysfs_device.release = zfcp_sysfs_unit_release;
 285         dev_set_drvdata(&unit->sysfs_device, unit);
 286
 287         /* mark unit unusable as long as sysfs registration is not complete */
 288         atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
 289
 290         spin_lock_init(&unit->latencies.lock);
 291         unit->latencies.write.channel.min = 0xFFFFFFFF;
 292         unit->latencies.write.fabric.min = 0xFFFFFFFF;
 293         unit->latencies.read.channel.min = 0xFFFFFFFF;
 294         unit->latencies.read.fabric.min = 0xFFFFFFFF;
 295         unit->latencies.cmd.channel.min = 0xFFFFFFFF;
 296         unit->latencies.cmd.fabric.min = 0xFFFFFFFF;
 297
 298         read_lock_irq(&zfcp_data.config_lock);
 299         if (zfcp_get_unit_by_lun(port, fcp_lun)) {
 300                 read_unlock_irq(&zfcp_data.config_lock);
 301                 goto err_out_free;
 302         }
 303         read_unlock_irq(&zfcp_data.config_lock);
 304
 305         if (device_register(&unit->sysfs_device))
 306                 goto err_out_free;
 307
 308         if (sysfs_create_group(&unit->sysfs_device.kobj,
 309                                &zfcp_sysfs_unit_attrs)) {
 310                 device_unregister(&unit->sysfs_device);
 311                 return ERR_PTR(-EIO);
 312         }
 313
 314         zfcp_unit_get(unit);
 315
 316         write_lock_irq(&zfcp_data.config_lock);
 317         list_add_tail(&unit->list, &port->unit_list_head);
 318         atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
 319         atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status);
 320
 321         write_unlock_irq(&zfcp_data.config_lock);
 322
 323         zfcp_port_get(port);
 324
 325         return unit;
 326
 327 err_out_free:
 328         kfree(unit);
 329         return ERR_PTR(-EINVAL);
 330 }
 331
 332 /**
 333  * zfcp_unit_dequeue - dequeue unit
 334  * @unit: pointer to zfcp_unit
 335  *
 336  * waits until all work is done on unit and removes it then from the unit->list
 337  * of the associated port.
 338  */
 339 void zfcp_unit_dequeue(struct zfcp_unit *unit)
 340 {
 341         wait_event(unit->remove_wq, atomic_read(&unit->refcount) == 0);
 342         write_lock_irq(&zfcp_data.config_lock);
 343         list_del(&unit->list);
 344         write_unlock_irq(&zfcp_data.config_lock);
 345         zfcp_port_put(unit->port);
 346         sysfs_remove_group(&unit->sysfs_device.kobj, &zfcp_sysfs_unit_attrs);
 347         device_unregister(&unit->sysfs_device);
 348 }
 349
 350 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
 351 {
 352         /* must only be called with zfcp_data.config_sema taken */
 353         adapter->pool.fsf_req_erp =
 354                 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
 355         if (!adapter->pool.fsf_req_erp)
 356                 return -ENOMEM;
 357
 358         adapter->pool.fsf_req_scsi =
 359                 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
 360         if (!adapter->pool.fsf_req_scsi)
 361                 return -ENOMEM;
 362
 363         adapter->pool.fsf_req_abort =
 364                 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
 365         if (!adapter->pool.fsf_req_abort)
 366                 return -ENOMEM;
 367
 368         adapter->pool.fsf_req_status_read =
 369                 mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
 370                                             sizeof(struct zfcp_fsf_req));
 371         if (!adapter->pool.fsf_req_status_read)
 372                 return -ENOMEM;
 373
 374         adapter->pool.data_status_read =
 375                 mempool_create_slab_pool(FSF_STATUS_READS_RECOM,
 376                                          zfcp_data.sr_buffer_cache);
 377         if (!adapter->pool.data_status_read)
 378                 return -ENOMEM;
 379
 380         adapter->pool.data_gid_pn =
 381                 mempool_create_slab_pool(1, zfcp_data.gid_pn_cache);
 382         if (!adapter->pool.data_gid_pn)
 383                 return -ENOMEM;
 384
 385         return 0;
 386 }
 387
 388 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
 389 {
 390         /* zfcp_data.config_sema must be held */
 391         if (adapter->pool.fsf_req_erp)
 392                 mempool_destroy(adapter->pool.fsf_req_erp);
 393         if (adapter->pool.fsf_req_scsi)
 394                 mempool_destroy(adapter->pool.fsf_req_scsi);
 395         if (adapter->pool.fsf_req_abort)
 396                 mempool_destroy(adapter->pool.fsf_req_abort);
 397         if (adapter->pool.fsf_req_status_read)
 398                 mempool_destroy(adapter->pool.fsf_req_status_read);
 399         if (adapter->pool.data_status_read)
 400                 mempool_destroy(adapter->pool.data_status_read);
 401         if (adapter->pool.data_gid_pn)
 402                 mempool_destroy(adapter->pool.data_gid_pn);
 403 }
 404
 405 /**
 406  * zfcp_status_read_refill - refill the long running status_read_requests
 407  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
 408  *
 409  * Returns: 0 on success, 1 otherwise
 410  *
 411  * if there are 16 or more status_read requests missing an adapter_reopen
 412  * is triggered
 413  */
 414 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
 415 {
 416         while (atomic_read(&adapter->stat_miss) > 0)
 417                 if (zfcp_fsf_status_read(adapter)) {
 418                         if (atomic_read(&adapter->stat_miss) >= 16) {
 419                                 zfcp_erp_adapter_reopen(adapter, 0, 103, NULL);
 420                                 return 1;
 421                         }
 422                         break;
 423                 } else
 424                         atomic_dec(&adapter->stat_miss);
 425         return 0;
 426 }
 427
 428 static void _zfcp_status_read_scheduler(struct work_struct *work)
 429 {
 430         zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
 431                                              stat_work));
 432 }
 433
 434 /**
 435  * zfcp_adapter_enqueue - enqueue a new adapter to the list
 436  * @ccw_device: pointer to the struct cc_device
 437  *
 438  * Returns:     0             if a new adapter was successfully enqueued
 439  *              -ENOMEM       if alloc failed
 440  * Enqueues an adapter at the end of the adapter list in the driver data.
 441  * All adapter internal structures are set up.
 442  * Proc-fs entries are also created.
 443  * locks:       config_sema must be held to serialise changes to the adapter list
 444  */
 445 int zfcp_adapter_enqueue(struct ccw_device *ccw_device)
 446 {
 447         struct zfcp_adapter *adapter;
 448
 449         /*
 450          * Note: It is safe to release the list_lock, as any list changes
 451          * are protected by the config_sema, which must be held to get here
 452          */
 453
 454         adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
 455         if (!adapter)
 456                 return -ENOMEM;
 457
 458         ccw_device->handler = NULL;
 459         adapter->ccw_device = ccw_device;
 460         atomic_set(&adapter->refcount, 0);
 461
 462         if (zfcp_qdio_allocate(adapter))
 463                 goto qdio_allocate_failed;
 464
 465         if (zfcp_allocate_low_mem_buffers(adapter))
 466                 goto failed_low_mem_buffers;
 467
 468         if (zfcp_reqlist_alloc(adapter))
 469                 goto failed_low_mem_buffers;
 470
 471         if (zfcp_adapter_debug_register(adapter))
 472                 goto debug_register_failed;
 473
 474         init_waitqueue_head(&adapter->remove_wq);
 475         init_waitqueue_head(&adapter->erp_thread_wqh);
 476         init_waitqueue_head(&adapter->erp_done_wqh);
 477
 478         INIT_LIST_HEAD(&adapter->port_list_head);
 479         INIT_LIST_HEAD(&adapter->erp_ready_head);
 480         INIT_LIST_HEAD(&adapter->erp_running_head);
 481
 482         spin_lock_init(&adapter->req_list_lock);
 483
 484         spin_lock_init(&adapter->hba_dbf_lock);
 485         spin_lock_init(&adapter->san_dbf_lock);
 486         spin_lock_init(&adapter->scsi_dbf_lock);
 487         spin_lock_init(&adapter->rec_dbf_lock);
 488         spin_lock_init(&adapter->req_q_lock);
 489
 490         rwlock_init(&adapter->erp_lock);
 491         rwlock_init(&adapter->abort_lock);
 492
 493         sema_init(&adapter->erp_ready_sem, 0);
 494
 495         INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
 496         INIT_WORK(&adapter->scan_work, _zfcp_scan_ports_later);
 497
 498         /* mark adapter unusable as long as sysfs registration is not complete */
 499         atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
 500
 501         dev_set_drvdata(&ccw_device->dev, adapter);
 502
 503         if (sysfs_create_group(&ccw_device->dev.kobj,
 504                                &zfcp_sysfs_adapter_attrs))
 505                 goto sysfs_failed;
 506
 507         write_lock_irq(&zfcp_data.config_lock);
 508         atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
 509         list_add_tail(&adapter->list, &zfcp_data.adapter_list_head);
 510         write_unlock_irq(&zfcp_data.config_lock);
 511
 512         zfcp_fc_nameserver_init(adapter);
 513
 514         return 0;
 515
 516 sysfs_failed:
 517         zfcp_adapter_debug_unregister(adapter);
 518 debug_register_failed:
 519         dev_set_drvdata(&ccw_device->dev, NULL);
 520         kfree(adapter->req_list);
 521 failed_low_mem_buffers:
 522         zfcp_free_low_mem_buffers(adapter);
 523 qdio_allocate_failed:
 524         zfcp_qdio_free(adapter);
 525         kfree(adapter);
 526         return -ENOMEM;
 527 }
 528
 529 /**
 530  * zfcp_adapter_dequeue - remove the adapter from the resource list
 531  * @adapter: pointer to struct zfcp_adapter which should be removed
 532  * locks:       adapter list write lock is assumed to be held by caller
 533  */
 534 void zfcp_adapter_dequeue(struct zfcp_adapter *adapter)
 535 {
 536         int retval = 0;
 537         unsigned long flags;
 538
 539         cancel_work_sync(&adapter->scan_work);
 540         cancel_work_sync(&adapter->stat_work);
 541         zfcp_adapter_scsi_unregister(adapter);
 542         sysfs_remove_group(&adapter->ccw_device->dev.kobj,
 543                            &zfcp_sysfs_adapter_attrs);
 544         dev_set_drvdata(&adapter->ccw_device->dev, NULL);
 545         /* sanity check: no pending FSF requests */
 546         spin_lock_irqsave(&adapter->req_list_lock, flags);
 547         retval = zfcp_reqlist_isempty(adapter);
 548         spin_unlock_irqrestore(&adapter->req_list_lock, flags);
 549         if (!retval)
 550                 return;
 551
 552         zfcp_adapter_debug_unregister(adapter);
 553
 554         /* remove specified adapter data structure from list */
 555         write_lock_irq(&zfcp_data.config_lock);
 556         list_del(&adapter->list);
 557         write_unlock_irq(&zfcp_data.config_lock);
 558
 559         zfcp_qdio_free(adapter);
 560
 561         zfcp_free_low_mem_buffers(adapter);
 562         kfree(adapter->req_list);
 563         kfree(adapter->fc_stats);
 564         kfree(adapter->stats_reset_data);
 565         kfree(adapter);
 566 }
 567
 568 static void zfcp_sysfs_port_release(struct device *dev)
 569 {
 570         kfree(container_of(dev, struct zfcp_port, sysfs_device));
 571 }
 572
 573 /**
 574  * zfcp_port_enqueue - enqueue port to port list of adapter
 575  * @adapter: adapter where remote port is added
 576  * @wwpn: WWPN of the remote port to be enqueued
 577  * @status: initial status for the port
 578  * @d_id: destination id of the remote port to be enqueued
 579  * Returns: pointer to enqueued port on success, ERR_PTR on error
 580  * Locks: config_sema must be held to serialize changes to the port list
 581  *
 582  * All port internal structures are set up and the sysfs entry is generated.
 583  * d_id is used to enqueue ports with a well known address like the Directory
 584  * Service for nameserver lookup.
 585  */
 586 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
 587                                      u32 status, u32 d_id)
 588 {
 589         struct zfcp_port *port;
 590         int retval;
 591
 592         port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
 593         if (!port)
 594                 return ERR_PTR(-ENOMEM);
 595
 596         init_waitqueue_head(&port->remove_wq);
 597         INIT_LIST_HEAD(&port->unit_list_head);
 598         INIT_WORK(&port->gid_pn_work, zfcp_erp_port_strategy_open_lookup);
 599
 600         port->adapter = adapter;
 601         port->d_id = d_id;
 602         port->wwpn = wwpn;
 603
 604         /* mark port unusable as long as sysfs registration is not complete */
 605         atomic_set_mask(status | ZFCP_STATUS_COMMON_REMOVE, &port->status);
 606         atomic_set(&port->refcount, 0);
 607
 608         snprintf(port->sysfs_device.bus_id, BUS_ID_SIZE, "0x%016llx",
 609                  (unsigned long long) wwpn);
 610         port->sysfs_device.parent = &adapter->ccw_device->dev;
 611
 612         port->sysfs_device.release = zfcp_sysfs_port_release;
 613         dev_set_drvdata(&port->sysfs_device, port);
 614
 615         read_lock_irq(&zfcp_data.config_lock);
 616         if (!(status & ZFCP_STATUS_PORT_NO_WWPN))
 617                 if (zfcp_get_port_by_wwpn(adapter, wwpn)) {
 618                         read_unlock_irq(&zfcp_data.config_lock);
 619                         goto err_out_free;
 620                 }
 621         read_unlock_irq(&zfcp_data.config_lock);
 622
 623         if (device_register(&port->sysfs_device))
 624                 goto err_out_free;
 625
 626         retval = sysfs_create_group(&port->sysfs_device.kobj,
 627                                     &zfcp_sysfs_port_attrs);
 628
 629         if (retval) {
 630                 device_unregister(&port->sysfs_device);
 631                 goto err_out;
 632         }
 633
 634         zfcp_port_get(port);
 635
 636         write_lock_irq(&zfcp_data.config_lock);
 637         list_add_tail(&port->list, &adapter->port_list_head);
 638         atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &port->status);
 639         atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &port->status);
 640
 641         write_unlock_irq(&zfcp_data.config_lock);
 642
 643         zfcp_adapter_get(adapter);
 644         return port;
 645
 646 err_out_free:
 647         kfree(port);
 648 err_out:
 649         return ERR_PTR(-EINVAL);
 650 }
 651
 652 /**
 653  * zfcp_port_dequeue - dequeues a port from the port list of the adapter
 654  * @port: pointer to struct zfcp_port which should be removed
 655  */
 656 void zfcp_port_dequeue(struct zfcp_port *port)
 657 {
 658         wait_event(port->remove_wq, atomic_read(&port->refcount) == 0);
 659         write_lock_irq(&zfcp_data.config_lock);
 660         list_del(&port->list);
 661         write_unlock_irq(&zfcp_data.config_lock);
 662         if (port->rport)
 663                 fc_remote_port_delete(port->rport);
 664         port->rport = NULL;
 665         zfcp_adapter_put(port->adapter);
 666         sysfs_remove_group(&port->sysfs_device.kobj, &zfcp_sysfs_port_attrs);
 667         device_unregister(&port->sysfs_device);
 668 }
 669
 670 /**
 671  * zfcp_sg_free_table - free memory used by scatterlists
 672  * @sg: pointer to scatterlist
 673  * @count: number of scatterlist which are to be free'ed
 674  * the scatterlist are expected to reference pages always
 675  */
 676 void zfcp_sg_free_table(struct scatterlist *sg, int count)
 677 {
 678         int i;
 679
 680         for (i = 0; i < count; i++, sg++)
 681                 if (sg)
 682                         free_page((unsigned long) sg_virt(sg));
 683                 else
 684                         break;
 685 }
 686
 687 /**
 688  * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
 689  * @sg: pointer to struct scatterlist
 690  * @count: number of scatterlists which should be assigned with buffers
 691  * of size page
 692  *
 693  * Returns: 0 on success, -ENOMEM otherwise
 694  */
 695 int zfcp_sg_setup_table(struct scatterlist *sg, int count)
 696 {
 697         void *addr;
 698         int i;
 699
 700         sg_init_table(sg, count);
 701         for (i = 0; i < count; i++, sg++) {
 702                 addr = (void *) get_zeroed_page(GFP_KERNEL);
 703                 if (!addr) {
 704                         zfcp_sg_free_table(sg, i);
 705                         return -ENOMEM;
 706                 }
 707                 sg_set_buf(sg, addr, PAGE_SIZE);
 708         }
 709         return 0;
 710 }