git.oblomov.eu Git - linux-2.6/blob - drivers/s390/scsi/zfcp_aux.c

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