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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 <linux/seq_file.h>
  30 #include "zfcp_ext.h"
  31
  32 #define ZFCP_BUS_ID_SIZE        20
  33
  34 static char *device;
  35
  36 MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
  37 MODULE_DESCRIPTION("FCP HBA driver");
  38 MODULE_LICENSE("GPL");
  39
  40 module_param(device, charp, 0400);
  41 MODULE_PARM_DESC(device, "specify initial device");
  42
  43 static int zfcp_reqlist_alloc(struct zfcp_adapter *adapter)
  44 {
  45         int idx;
  46
  47         adapter->req_list = kcalloc(REQUEST_LIST_SIZE, sizeof(struct list_head),
  48                                     GFP_KERNEL);
  49         if (!adapter->req_list)
  50                 return -ENOMEM;
  51
  52         for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
  53                 INIT_LIST_HEAD(&adapter->req_list[idx]);
  54         return 0;
  55 }
  56
  57 /**
  58  * zfcp_reqlist_isempty - is the request list empty
  59  * @adapter: pointer to struct zfcp_adapter
  60  *
  61  * Returns: true if list is empty, false otherwise
  62  */
  63 int zfcp_reqlist_isempty(struct zfcp_adapter *adapter)
  64 {
  65         unsigned int idx;
  66
  67         for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
  68                 if (!list_empty(&adapter->req_list[idx]))
  69                         return 0;
  70         return 1;
  71 }
  72
  73 static int __init zfcp_device_setup(char *devstr)
  74 {
  75         char *token;
  76         char *str;
  77
  78         if (!devstr)
  79                 return 0;
  80
  81         /* duplicate devstr and keep the original for sysfs presentation*/
  82         str = kmalloc(strlen(devstr) + 1, GFP_KERNEL);
  83         if (!str)
  84                 return 0;
  85
  86         strcpy(str, devstr);
  87
  88         token = strsep(&str, ",");
  89         if (!token || strlen(token) >= ZFCP_BUS_ID_SIZE)
  90                 goto err_out;
  91         strncpy(zfcp_data.init_busid, token, ZFCP_BUS_ID_SIZE);
  92
  93         token = strsep(&str, ",");
  94         if (!token || strict_strtoull(token, 0,
  95                                 (unsigned long long *) &zfcp_data.init_wwpn))
  96                 goto err_out;
  97
  98         token = strsep(&str, ",");
  99         if (!token || strict_strtoull(token, 0,
 100                                 (unsigned long long *) &zfcp_data.init_fcp_lun))
 101                 goto err_out;
 102
 103         kfree(str);
 104         return 1;
 105
 106  err_out:
 107         kfree(str);
 108         pr_err("zfcp: %s is not a valid SCSI device\n", devstr);
 109         return 0;
 110 }
 111
 112 static void __init zfcp_init_device_configure(void)
 113 {
 114         struct zfcp_adapter *adapter;
 115         struct zfcp_port *port;
 116         struct zfcp_unit *unit;
 117
 118         down(&zfcp_data.config_sema);
 119         read_lock_irq(&zfcp_data.config_lock);
 120         adapter = zfcp_get_adapter_by_busid(zfcp_data.init_busid);
 121         if (adapter)
 122                 zfcp_adapter_get(adapter);
 123         read_unlock_irq(&zfcp_data.config_lock);
 124
 125         if (!adapter)
 126                 goto out_adapter;
 127         port = zfcp_port_enqueue(adapter, zfcp_data.init_wwpn, 0, 0);
 128         if (IS_ERR(port))
 129                 goto out_port;
 130         unit = zfcp_unit_enqueue(port, zfcp_data.init_fcp_lun);
 131         if (IS_ERR(unit))
 132                 goto out_unit;
 133         up(&zfcp_data.config_sema);
 134         ccw_device_set_online(adapter->ccw_device);
 135
 136         zfcp_erp_wait(adapter);
 137         wait_event(adapter->erp_done_wqh,
 138                    !(atomic_read(&unit->status) &
 139                                 ZFCP_STATUS_UNIT_SCSI_WORK_PENDING));
 140
 141         down(&zfcp_data.config_sema);
 142         zfcp_unit_put(unit);
 143 out_unit:
 144         zfcp_port_put(port);
 145 out_port:
 146         zfcp_adapter_put(adapter);
 147 out_adapter:
 148         up(&zfcp_data.config_sema);
 149         return;
 150 }
 151
 152 static struct kmem_cache *zfcp_cache_create(int size, char *name)
 153 {
 154         int align = 1;
 155         while ((size - align) > 0)
 156                 align <<= 1;
 157         return kmem_cache_create(name , size, align, 0, NULL);
 158 }
 159
 160 static int __init zfcp_module_init(void)
 161 {
 162         int retval = -ENOMEM;
 163
 164         zfcp_data.fsf_req_qtcb_cache = zfcp_cache_create(
 165                         sizeof(struct zfcp_fsf_req_qtcb), "zfcp_fsf");
 166         if (!zfcp_data.fsf_req_qtcb_cache)
 167                 goto out;
 168
 169         zfcp_data.sr_buffer_cache = zfcp_cache_create(
 170                         sizeof(struct fsf_status_read_buffer), "zfcp_sr");
 171         if (!zfcp_data.sr_buffer_cache)
 172                 goto out_sr_cache;
 173
 174         zfcp_data.gid_pn_cache = zfcp_cache_create(
 175                         sizeof(struct zfcp_gid_pn_data), "zfcp_gid");
 176         if (!zfcp_data.gid_pn_cache)
 177                 goto out_gid_cache;
 178
 179         zfcp_data.work_queue = create_singlethread_workqueue("zfcp_wq");
 180
 181         INIT_LIST_HEAD(&zfcp_data.adapter_list_head);
 182         sema_init(&zfcp_data.config_sema, 1);
 183         rwlock_init(&zfcp_data.config_lock);
 184
 185         zfcp_data.scsi_transport_template =
 186                 fc_attach_transport(&zfcp_transport_functions);
 187         if (!zfcp_data.scsi_transport_template)
 188                 goto out_transport;
 189
 190         retval = misc_register(&zfcp_cfdc_misc);
 191         if (retval) {
 192                 pr_err("zfcp: Registering the misc device zfcp_cfdc failed\n");
 193                 goto out_misc;
 194         }
 195
 196         retval = zfcp_ccw_register();
 197         if (retval) {
 198                 pr_err("zfcp: The zfcp device driver could not register with "
 199                        "the common I/O layer\n");
 200                 goto out_ccw_register;
 201         }
 202
 203         if (zfcp_device_setup(device))
 204                 zfcp_init_device_configure();
 205
 206         goto out;
 207
 208 out_ccw_register:
 209         misc_deregister(&zfcp_cfdc_misc);
 210 out_misc:
 211         fc_release_transport(zfcp_data.scsi_transport_template);
 212 out_transport:
 213         kmem_cache_destroy(zfcp_data.gid_pn_cache);
 214 out_gid_cache:
 215         kmem_cache_destroy(zfcp_data.sr_buffer_cache);
 216 out_sr_cache:
 217         kmem_cache_destroy(zfcp_data.fsf_req_qtcb_cache);
 218 out:
 219         return retval;
 220 }
 221
 222 module_init(zfcp_module_init);
 223
 224 /**
 225  * zfcp_get_unit_by_lun - find unit in unit list of port by FCP LUN
 226  * @port: pointer to port to search for unit
 227  * @fcp_lun: FCP LUN to search for
 228  *
 229  * Returns: pointer to zfcp_unit or NULL
 230  */
 231 struct zfcp_unit *zfcp_get_unit_by_lun(struct zfcp_port *port, u64 fcp_lun)
 232 {
 233         struct zfcp_unit *unit;
 234
 235         list_for_each_entry(unit, &port->unit_list_head, list)
 236                 if ((unit->fcp_lun == fcp_lun) &&
 237                     !(atomic_read(&unit->status) & ZFCP_STATUS_COMMON_REMOVE))
 238                     return unit;
 239         return NULL;
 240 }
 241
 242 /**
 243  * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
 244  * @adapter: pointer to adapter to search for port
 245  * @wwpn: wwpn to search for
 246  *
 247  * Returns: pointer to zfcp_port or NULL
 248  */
 249 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
 250                                         u64 wwpn)
 251 {
 252         struct zfcp_port *port;
 253
 254         list_for_each_entry(port, &adapter->port_list_head, list)
 255                 if ((port->wwpn == wwpn) && !(atomic_read(&port->status) &
 256                       (ZFCP_STATUS_PORT_NO_WWPN | ZFCP_STATUS_COMMON_REMOVE)))
 257                         return port;
 258         return NULL;
 259 }
 260
 261 static void zfcp_sysfs_unit_release(struct device *dev)
 262 {
 263         kfree(container_of(dev, struct zfcp_unit, sysfs_device));
 264 }
 265
 266 /**
 267  * zfcp_unit_enqueue - enqueue unit to unit list of a port.
 268  * @port: pointer to port where unit is added
 269  * @fcp_lun: FCP LUN of unit to be enqueued
 270  * Returns: pointer to enqueued unit on success, ERR_PTR on error
 271  * Locks: config_sema must be held to serialize changes to the unit list
 272  *
 273  * Sets up some unit internal structures and creates sysfs entry.
 274  */
 275 struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
 276 {
 277         struct zfcp_unit *unit;
 278
 279         unit = kzalloc(sizeof(struct zfcp_unit), GFP_KERNEL);
 280         if (!unit)
 281                 return ERR_PTR(-ENOMEM);
 282
 283         atomic_set(&unit->refcount, 0);
 284         init_waitqueue_head(&unit->remove_wq);
 285
 286         unit->port = port;
 287         unit->fcp_lun = fcp_lun;
 288
 289         dev_set_name(&unit->sysfs_device, "0x%016llx",
 290                      (unsigned long long) fcp_lun);
 291         unit->sysfs_device.parent = &port->sysfs_device;
 292         unit->sysfs_device.release = zfcp_sysfs_unit_release;
 293         dev_set_drvdata(&unit->sysfs_device, unit);
 294
 295         /* mark unit unusable as long as sysfs registration is not complete */
 296         atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
 297
 298         spin_lock_init(&unit->latencies.lock);
 299         unit->latencies.write.channel.min = 0xFFFFFFFF;
 300         unit->latencies.write.fabric.min = 0xFFFFFFFF;
 301         unit->latencies.read.channel.min = 0xFFFFFFFF;
 302         unit->latencies.read.fabric.min = 0xFFFFFFFF;
 303         unit->latencies.cmd.channel.min = 0xFFFFFFFF;
 304         unit->latencies.cmd.fabric.min = 0xFFFFFFFF;
 305
 306         read_lock_irq(&zfcp_data.config_lock);
 307         if (zfcp_get_unit_by_lun(port, fcp_lun)) {
 308                 read_unlock_irq(&zfcp_data.config_lock);
 309                 goto err_out_free;
 310         }
 311         read_unlock_irq(&zfcp_data.config_lock);
 312
 313         if (device_register(&unit->sysfs_device))
 314                 goto err_out_free;
 315
 316         if (sysfs_create_group(&unit->sysfs_device.kobj,
 317                                &zfcp_sysfs_unit_attrs)) {
 318                 device_unregister(&unit->sysfs_device);
 319                 return ERR_PTR(-EIO);
 320         }
 321
 322         zfcp_unit_get(unit);
 323
 324         write_lock_irq(&zfcp_data.config_lock);
 325         list_add_tail(&unit->list, &port->unit_list_head);
 326         atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
 327         atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status);
 328
 329         write_unlock_irq(&zfcp_data.config_lock);
 330
 331         zfcp_port_get(port);
 332
 333         return unit;
 334
 335 err_out_free:
 336         kfree(unit);
 337         return ERR_PTR(-EINVAL);
 338 }
 339
 340 /**
 341  * zfcp_unit_dequeue - dequeue unit
 342  * @unit: pointer to zfcp_unit
 343  *
 344  * waits until all work is done on unit and removes it then from the unit->list
 345  * of the associated port.
 346  */
 347 void zfcp_unit_dequeue(struct zfcp_unit *unit)
 348 {
 349         wait_event(unit->remove_wq, atomic_read(&unit->refcount) == 0);
 350         write_lock_irq(&zfcp_data.config_lock);
 351         list_del(&unit->list);
 352         write_unlock_irq(&zfcp_data.config_lock);
 353         zfcp_port_put(unit->port);
 354         sysfs_remove_group(&unit->sysfs_device.kobj, &zfcp_sysfs_unit_attrs);
 355         device_unregister(&unit->sysfs_device);
 356 }
 357
 358 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
 359 {
 360         /* must only be called with zfcp_data.config_sema taken */
 361         adapter->pool.fsf_req_erp =
 362                 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
 363         if (!adapter->pool.fsf_req_erp)
 364                 return -ENOMEM;
 365
 366         adapter->pool.fsf_req_scsi =
 367                 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
 368         if (!adapter->pool.fsf_req_scsi)
 369                 return -ENOMEM;
 370
 371         adapter->pool.fsf_req_abort =
 372                 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
 373         if (!adapter->pool.fsf_req_abort)
 374                 return -ENOMEM;
 375
 376         adapter->pool.fsf_req_status_read =
 377                 mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
 378                                             sizeof(struct zfcp_fsf_req));
 379         if (!adapter->pool.fsf_req_status_read)
 380                 return -ENOMEM;
 381
 382         adapter->pool.data_status_read =
 383                 mempool_create_slab_pool(FSF_STATUS_READS_RECOM,
 384                                          zfcp_data.sr_buffer_cache);
 385         if (!adapter->pool.data_status_read)
 386                 return -ENOMEM;
 387
 388         adapter->pool.data_gid_pn =
 389                 mempool_create_slab_pool(1, zfcp_data.gid_pn_cache);
 390         if (!adapter->pool.data_gid_pn)
 391                 return -ENOMEM;
 392
 393         return 0;
 394 }
 395
 396 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
 397 {
 398         /* zfcp_data.config_sema must be held */
 399         if (adapter->pool.fsf_req_erp)
 400                 mempool_destroy(adapter->pool.fsf_req_erp);
 401         if (adapter->pool.fsf_req_scsi)
 402                 mempool_destroy(adapter->pool.fsf_req_scsi);
 403         if (adapter->pool.fsf_req_abort)
 404                 mempool_destroy(adapter->pool.fsf_req_abort);
 405         if (adapter->pool.fsf_req_status_read)
 406                 mempool_destroy(adapter->pool.fsf_req_status_read);
 407         if (adapter->pool.data_status_read)
 408                 mempool_destroy(adapter->pool.data_status_read);
 409         if (adapter->pool.data_gid_pn)
 410                 mempool_destroy(adapter->pool.data_gid_pn);
 411 }
 412
 413 /**
 414  * zfcp_status_read_refill - refill the long running status_read_requests
 415  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
 416  *
 417  * Returns: 0 on success, 1 otherwise
 418  *
 419  * if there are 16 or more status_read requests missing an adapter_reopen
 420  * is triggered
 421  */
 422 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
 423 {
 424         while (atomic_read(&adapter->stat_miss) > 0)
 425                 if (zfcp_fsf_status_read(adapter)) {
 426                         if (atomic_read(&adapter->stat_miss) >= 16) {
 427                                 zfcp_erp_adapter_reopen(adapter, 0, 103, NULL);
 428                                 return 1;
 429                         }
 430                         break;
 431                 } else
 432                         atomic_dec(&adapter->stat_miss);
 433         return 0;
 434 }
 435
 436 static void _zfcp_status_read_scheduler(struct work_struct *work)
 437 {
 438         zfcp_status_read_refill(container_of(work, struct zfcp_adapter,
 439                                              stat_work));
 440 }
 441
 442 static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
 443 {
 444         struct zfcp_adapter *adapter =
 445                 container_of(sl, struct zfcp_adapter, service_level);
 446
 447         seq_printf(m, "zfcp: %s microcode level %x\n",
 448                    dev_name(&adapter->ccw_device->dev),
 449                    adapter->fsf_lic_version);
 450 }
 451
 452 /**
 453  * zfcp_adapter_enqueue - enqueue a new adapter to the list
 454  * @ccw_device: pointer to the struct cc_device
 455  *
 456  * Returns:     0             if a new adapter was successfully enqueued
 457  *              -ENOMEM       if alloc failed
 458  * Enqueues an adapter at the end of the adapter list in the driver data.
 459  * All adapter internal structures are set up.
 460  * Proc-fs entries are also created.
 461  * locks:       config_sema must be held to serialise changes to the adapter list
 462  */
 463 int zfcp_adapter_enqueue(struct ccw_device *ccw_device)
 464 {
 465         struct zfcp_adapter *adapter;
 466
 467         /*
 468          * Note: It is safe to release the list_lock, as any list changes
 469          * are protected by the config_sema, which must be held to get here
 470          */
 471
 472         adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
 473         if (!adapter)
 474                 return -ENOMEM;
 475
 476         ccw_device->handler = NULL;
 477         adapter->ccw_device = ccw_device;
 478         atomic_set(&adapter->refcount, 0);
 479
 480         if (zfcp_qdio_allocate(adapter))
 481                 goto qdio_allocate_failed;
 482
 483         if (zfcp_allocate_low_mem_buffers(adapter))
 484                 goto failed_low_mem_buffers;
 485
 486         if (zfcp_reqlist_alloc(adapter))
 487                 goto failed_low_mem_buffers;
 488
 489         if (zfcp_adapter_debug_register(adapter))
 490                 goto debug_register_failed;
 491
 492         init_waitqueue_head(&adapter->remove_wq);
 493         init_waitqueue_head(&adapter->erp_thread_wqh);
 494         init_waitqueue_head(&adapter->erp_done_wqh);
 495
 496         INIT_LIST_HEAD(&adapter->port_list_head);
 497         INIT_LIST_HEAD(&adapter->erp_ready_head);
 498         INIT_LIST_HEAD(&adapter->erp_running_head);
 499
 500         spin_lock_init(&adapter->req_list_lock);
 501
 502         spin_lock_init(&adapter->hba_dbf_lock);
 503         spin_lock_init(&adapter->san_dbf_lock);
 504         spin_lock_init(&adapter->scsi_dbf_lock);
 505         spin_lock_init(&adapter->rec_dbf_lock);
 506         spin_lock_init(&adapter->req_q_lock);
 507
 508         rwlock_init(&adapter->erp_lock);
 509         rwlock_init(&adapter->abort_lock);
 510
 511         sema_init(&adapter->erp_ready_sem, 0);
 512
 513         INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
 514         INIT_WORK(&adapter->scan_work, _zfcp_scan_ports_later);
 515
 516         adapter->service_level.seq_print = zfcp_print_sl;
 517
 518         /* mark adapter unusable as long as sysfs registration is not complete */
 519         atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
 520
 521         dev_set_drvdata(&ccw_device->dev, adapter);
 522
 523         if (sysfs_create_group(&ccw_device->dev.kobj,
 524                                &zfcp_sysfs_adapter_attrs))
 525                 goto sysfs_failed;
 526
 527         write_lock_irq(&zfcp_data.config_lock);
 528         atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
 529         list_add_tail(&adapter->list, &zfcp_data.adapter_list_head);
 530         write_unlock_irq(&zfcp_data.config_lock);
 531
 532         zfcp_fc_nameserver_init(adapter);
 533
 534         return 0;
 535
 536 sysfs_failed:
 537         zfcp_adapter_debug_unregister(adapter);
 538 debug_register_failed:
 539         dev_set_drvdata(&ccw_device->dev, NULL);
 540         kfree(adapter->req_list);
 541 failed_low_mem_buffers:
 542         zfcp_free_low_mem_buffers(adapter);
 543 qdio_allocate_failed:
 544         zfcp_qdio_free(adapter);
 545         kfree(adapter);
 546         return -ENOMEM;
 547 }
 548
 549 /**
 550  * zfcp_adapter_dequeue - remove the adapter from the resource list
 551  * @adapter: pointer to struct zfcp_adapter which should be removed
 552  * locks:       adapter list write lock is assumed to be held by caller
 553  */
 554 void zfcp_adapter_dequeue(struct zfcp_adapter *adapter)
 555 {
 556         int retval = 0;
 557         unsigned long flags;
 558
 559         cancel_work_sync(&adapter->scan_work);
 560         cancel_work_sync(&adapter->stat_work);
 561         zfcp_adapter_scsi_unregister(adapter);
 562         sysfs_remove_group(&adapter->ccw_device->dev.kobj,
 563                            &zfcp_sysfs_adapter_attrs);
 564         dev_set_drvdata(&adapter->ccw_device->dev, NULL);
 565         /* sanity check: no pending FSF requests */
 566         spin_lock_irqsave(&adapter->req_list_lock, flags);
 567         retval = zfcp_reqlist_isempty(adapter);
 568         spin_unlock_irqrestore(&adapter->req_list_lock, flags);
 569         if (!retval)
 570                 return;
 571
 572         zfcp_adapter_debug_unregister(adapter);
 573
 574         /* remove specified adapter data structure from list */
 575         write_lock_irq(&zfcp_data.config_lock);
 576         list_del(&adapter->list);
 577         write_unlock_irq(&zfcp_data.config_lock);
 578
 579         zfcp_qdio_free(adapter);
 580
 581         zfcp_free_low_mem_buffers(adapter);
 582         kfree(adapter->req_list);
 583         kfree(adapter->fc_stats);
 584         kfree(adapter->stats_reset_data);
 585         kfree(adapter);
 586 }
 587
 588 static void zfcp_sysfs_port_release(struct device *dev)
 589 {
 590         kfree(container_of(dev, struct zfcp_port, sysfs_device));
 591 }
 592
 593 /**
 594  * zfcp_port_enqueue - enqueue port to port list of adapter
 595  * @adapter: adapter where remote port is added
 596  * @wwpn: WWPN of the remote port to be enqueued
 597  * @status: initial status for the port
 598  * @d_id: destination id of the remote port to be enqueued
 599  * Returns: pointer to enqueued port on success, ERR_PTR on error
 600  * Locks: config_sema must be held to serialize changes to the port list
 601  *
 602  * All port internal structures are set up and the sysfs entry is generated.
 603  * d_id is used to enqueue ports with a well known address like the Directory
 604  * Service for nameserver lookup.
 605  */
 606 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
 607                                      u32 status, u32 d_id)
 608 {
 609         struct zfcp_port *port;
 610         int retval;
 611
 612         port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
 613         if (!port)
 614                 return ERR_PTR(-ENOMEM);
 615
 616         init_waitqueue_head(&port->remove_wq);
 617         INIT_LIST_HEAD(&port->unit_list_head);
 618         INIT_WORK(&port->gid_pn_work, zfcp_erp_port_strategy_open_lookup);
 619
 620         port->adapter = adapter;
 621         port->d_id = d_id;
 622         port->wwpn = wwpn;
 623
 624         /* mark port unusable as long as sysfs registration is not complete */
 625         atomic_set_mask(status | ZFCP_STATUS_COMMON_REMOVE, &port->status);
 626         atomic_set(&port->refcount, 0);
 627
 628         dev_set_name(&port->sysfs_device, "0x%016llx",
 629                      (unsigned long long)wwpn);
 630         port->sysfs_device.parent = &adapter->ccw_device->dev;
 631
 632         port->sysfs_device.release = zfcp_sysfs_port_release;
 633         dev_set_drvdata(&port->sysfs_device, port);
 634
 635         read_lock_irq(&zfcp_data.config_lock);
 636         if (!(status & ZFCP_STATUS_PORT_NO_WWPN))
 637                 if (zfcp_get_port_by_wwpn(adapter, wwpn)) {
 638                         read_unlock_irq(&zfcp_data.config_lock);
 639                         goto err_out_free;
 640                 }
 641         read_unlock_irq(&zfcp_data.config_lock);
 642
 643         if (device_register(&port->sysfs_device))
 644                 goto err_out_free;
 645
 646         retval = sysfs_create_group(&port->sysfs_device.kobj,
 647                                     &zfcp_sysfs_port_attrs);
 648
 649         if (retval) {
 650                 device_unregister(&port->sysfs_device);
 651                 goto err_out;
 652         }
 653
 654         zfcp_port_get(port);
 655
 656         write_lock_irq(&zfcp_data.config_lock);
 657         list_add_tail(&port->list, &adapter->port_list_head);
 658         atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &port->status);
 659         atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &port->status);
 660
 661         write_unlock_irq(&zfcp_data.config_lock);
 662
 663         zfcp_adapter_get(adapter);
 664         return port;
 665
 666 err_out_free:
 667         kfree(port);
 668 err_out:
 669         return ERR_PTR(-EINVAL);
 670 }
 671
 672 /**
 673  * zfcp_port_dequeue - dequeues a port from the port list of the adapter
 674  * @port: pointer to struct zfcp_port which should be removed
 675  */
 676 void zfcp_port_dequeue(struct zfcp_port *port)
 677 {
 678         wait_event(port->remove_wq, atomic_read(&port->refcount) == 0);
 679         write_lock_irq(&zfcp_data.config_lock);
 680         list_del(&port->list);
 681         write_unlock_irq(&zfcp_data.config_lock);
 682         if (port->rport)
 683                 fc_remote_port_delete(port->rport);
 684         port->rport = NULL;
 685         zfcp_adapter_put(port->adapter);
 686         sysfs_remove_group(&port->sysfs_device.kobj, &zfcp_sysfs_port_attrs);
 687         device_unregister(&port->sysfs_device);
 688 }
 689
 690 /**
 691  * zfcp_sg_free_table - free memory used by scatterlists
 692  * @sg: pointer to scatterlist
 693  * @count: number of scatterlist which are to be free'ed
 694  * the scatterlist are expected to reference pages always
 695  */
 696 void zfcp_sg_free_table(struct scatterlist *sg, int count)
 697 {
 698         int i;
 699
 700         for (i = 0; i < count; i++, sg++)
 701                 if (sg)
 702                         free_page((unsigned long) sg_virt(sg));
 703                 else
 704                         break;
 705 }
 706
 707 /**
 708  * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
 709  * @sg: pointer to struct scatterlist
 710  * @count: number of scatterlists which should be assigned with buffers
 711  * of size page
 712  *
 713  * Returns: 0 on success, -ENOMEM otherwise
 714  */
 715 int zfcp_sg_setup_table(struct scatterlist *sg, int count)
 716 {
 717         void *addr;
 718         int i;
 719
 720         sg_init_table(sg, count);
 721         for (i = 0; i < count; i++, sg++) {
 722                 addr = (void *) get_zeroed_page(GFP_KERNEL);
 723                 if (!addr) {
 724                         zfcp_sg_free_table(sg, i);
 725                         return -ENOMEM;
 726                 }
 727                 sg_set_buf(sg, addr, PAGE_SIZE);
 728         }
 729         return 0;
 730 }