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, 2009
   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 #define KMSG_COMPONENT "zfcp"
  29 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  30
  31 #include <linux/miscdevice.h>
  32 #include <linux/seq_file.h>
  33 #include "zfcp_ext.h"
  34
  35 #define ZFCP_BUS_ID_SIZE        20
  36
  37 MODULE_AUTHOR("IBM Deutschland Entwicklung GmbH - linux390@de.ibm.com");
  38 MODULE_DESCRIPTION("FCP HBA driver");
  39 MODULE_LICENSE("GPL");
  40
  41 static char *init_device;
  42 module_param_named(device, init_device, charp, 0400);
  43 MODULE_PARM_DESC(device, "specify initial device");
  44
  45 static int zfcp_reqlist_alloc(struct zfcp_adapter *adapter)
  46 {
  47         int idx;
  48
  49         adapter->req_list = kcalloc(REQUEST_LIST_SIZE, sizeof(struct list_head),
  50                                     GFP_KERNEL);
  51         if (!adapter->req_list)
  52                 return -ENOMEM;
  53
  54         for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
  55                 INIT_LIST_HEAD(&adapter->req_list[idx]);
  56         return 0;
  57 }
  58
  59 /**
  60  * zfcp_reqlist_isempty - is the request list empty
  61  * @adapter: pointer to struct zfcp_adapter
  62  *
  63  * Returns: true if list is empty, false otherwise
  64  */
  65 int zfcp_reqlist_isempty(struct zfcp_adapter *adapter)
  66 {
  67         unsigned int idx;
  68
  69         for (idx = 0; idx < REQUEST_LIST_SIZE; idx++)
  70                 if (!list_empty(&adapter->req_list[idx]))
  71                         return 0;
  72         return 1;
  73 }
  74
  75 static void __init zfcp_init_device_configure(char *busid, u64 wwpn, u64 lun)
  76 {
  77         struct zfcp_adapter *adapter;
  78         struct zfcp_port *port;
  79         struct zfcp_unit *unit;
  80
  81         down(&zfcp_data.config_sema);
  82         read_lock_irq(&zfcp_data.config_lock);
  83         adapter = zfcp_get_adapter_by_busid(busid);
  84         if (adapter)
  85                 zfcp_adapter_get(adapter);
  86         read_unlock_irq(&zfcp_data.config_lock);
  87
  88         if (!adapter)
  89                 goto out_adapter;
  90         port = zfcp_port_enqueue(adapter, wwpn, 0, 0);
  91         if (IS_ERR(port))
  92                 goto out_port;
  93         unit = zfcp_unit_enqueue(port, lun);
  94         if (IS_ERR(unit))
  95                 goto out_unit;
  96         up(&zfcp_data.config_sema);
  97         ccw_device_set_online(adapter->ccw_device);
  98
  99         zfcp_erp_wait(adapter);
 100         flush_work(&unit->scsi_work);
 101
 102         down(&zfcp_data.config_sema);
 103         zfcp_unit_put(unit);
 104 out_unit:
 105         zfcp_port_put(port);
 106 out_port:
 107         zfcp_adapter_put(adapter);
 108 out_adapter:
 109         up(&zfcp_data.config_sema);
 110         return;
 111 }
 112
 113 static struct kmem_cache *zfcp_cache_create(int size, char *name)
 114 {
 115         int align = 1;
 116         while ((size - align) > 0)
 117                 align <<= 1;
 118         return kmem_cache_create(name , size, align, 0, NULL);
 119 }
 120
 121 static void __init zfcp_init_device_setup(char *devstr)
 122 {
 123         char *token;
 124         char *str;
 125         char busid[ZFCP_BUS_ID_SIZE];
 126         u64 wwpn, lun;
 127
 128         /* duplicate devstr and keep the original for sysfs presentation*/
 129         str = kmalloc(strlen(devstr) + 1, GFP_KERNEL);
 130         if (!str)
 131                 return;
 132
 133         strcpy(str, devstr);
 134
 135         token = strsep(&str, ",");
 136         if (!token || strlen(token) >= ZFCP_BUS_ID_SIZE)
 137                 goto err_out;
 138         strncpy(busid, token, ZFCP_BUS_ID_SIZE);
 139
 140         token = strsep(&str, ",");
 141         if (!token || strict_strtoull(token, 0, (unsigned long long *) &wwpn))
 142                 goto err_out;
 143
 144         token = strsep(&str, ",");
 145         if (!token || strict_strtoull(token, 0, (unsigned long long *) &lun))
 146                 goto err_out;
 147
 148         kfree(str);
 149         zfcp_init_device_configure(busid, wwpn, lun);
 150         return;
 151
 152  err_out:
 153         kfree(str);
 154         pr_err("%s is not a valid SCSI device\n", devstr);
 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         sema_init(&zfcp_data.config_sema, 1);
 179         rwlock_init(&zfcp_data.config_lock);
 180
 181         zfcp_data.scsi_transport_template =
 182                 fc_attach_transport(&zfcp_transport_functions);
 183         if (!zfcp_data.scsi_transport_template)
 184                 goto out_transport;
 185
 186         retval = misc_register(&zfcp_cfdc_misc);
 187         if (retval) {
 188                 pr_err("Registering the misc device zfcp_cfdc failed\n");
 189                 goto out_misc;
 190         }
 191
 192         retval = zfcp_ccw_register();
 193         if (retval) {
 194                 pr_err("The zfcp device driver could not register with "
 195                        "the common I/O layer\n");
 196                 goto out_ccw_register;
 197         }
 198
 199         if (init_device)
 200                 zfcp_init_device_setup(init_device);
 201         return 0;
 202
 203 out_ccw_register:
 204         misc_deregister(&zfcp_cfdc_misc);
 205 out_misc:
 206         fc_release_transport(zfcp_data.scsi_transport_template);
 207 out_transport:
 208         kmem_cache_destroy(zfcp_data.gid_pn_cache);
 209 out_gid_cache:
 210         kmem_cache_destroy(zfcp_data.sr_buffer_cache);
 211 out_sr_cache:
 212         kmem_cache_destroy(zfcp_data.fsf_req_qtcb_cache);
 213 out:
 214         return retval;
 215 }
 216
 217 module_init(zfcp_module_init);
 218
 219 /**
 220  * zfcp_get_unit_by_lun - find unit in unit list of port by FCP LUN
 221  * @port: pointer to port to search for unit
 222  * @fcp_lun: FCP LUN to search for
 223  *
 224  * Returns: pointer to zfcp_unit or NULL
 225  */
 226 struct zfcp_unit *zfcp_get_unit_by_lun(struct zfcp_port *port, u64 fcp_lun)
 227 {
 228         struct zfcp_unit *unit;
 229
 230         list_for_each_entry(unit, &port->unit_list_head, list)
 231                 if ((unit->fcp_lun == fcp_lun) &&
 232                     !(atomic_read(&unit->status) & ZFCP_STATUS_COMMON_REMOVE))
 233                     return unit;
 234         return NULL;
 235 }
 236
 237 /**
 238  * zfcp_get_port_by_wwpn - find port in port list of adapter by wwpn
 239  * @adapter: pointer to adapter to search for port
 240  * @wwpn: wwpn to search for
 241  *
 242  * Returns: pointer to zfcp_port or NULL
 243  */
 244 struct zfcp_port *zfcp_get_port_by_wwpn(struct zfcp_adapter *adapter,
 245                                         u64 wwpn)
 246 {
 247         struct zfcp_port *port;
 248
 249         list_for_each_entry(port, &adapter->port_list_head, list)
 250                 if ((port->wwpn == wwpn) &&
 251                     !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_REMOVE))
 252                         return port;
 253         return NULL;
 254 }
 255
 256 static void zfcp_sysfs_unit_release(struct device *dev)
 257 {
 258         kfree(container_of(dev, struct zfcp_unit, sysfs_device));
 259 }
 260
 261 /**
 262  * zfcp_unit_enqueue - enqueue unit to unit list of a port.
 263  * @port: pointer to port where unit is added
 264  * @fcp_lun: FCP LUN of unit to be enqueued
 265  * Returns: pointer to enqueued unit on success, ERR_PTR on error
 266  * Locks: config_sema must be held to serialize changes to the unit list
 267  *
 268  * Sets up some unit internal structures and creates sysfs entry.
 269  */
 270 struct zfcp_unit *zfcp_unit_enqueue(struct zfcp_port *port, u64 fcp_lun)
 271 {
 272         struct zfcp_unit *unit;
 273
 274         unit = kzalloc(sizeof(struct zfcp_unit), GFP_KERNEL);
 275         if (!unit)
 276                 return ERR_PTR(-ENOMEM);
 277
 278         atomic_set(&unit->refcount, 0);
 279         init_waitqueue_head(&unit->remove_wq);
 280         INIT_WORK(&unit->scsi_work, zfcp_scsi_scan);
 281
 282         unit->port = port;
 283         unit->fcp_lun = fcp_lun;
 284
 285         dev_set_name(&unit->sysfs_device, "0x%016llx",
 286                      (unsigned long long) fcp_lun);
 287         unit->sysfs_device.parent = &port->sysfs_device;
 288         unit->sysfs_device.release = zfcp_sysfs_unit_release;
 289         dev_set_drvdata(&unit->sysfs_device, unit);
 290
 291         /* mark unit unusable as long as sysfs registration is not complete */
 292         atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
 293
 294         spin_lock_init(&unit->latencies.lock);
 295         unit->latencies.write.channel.min = 0xFFFFFFFF;
 296         unit->latencies.write.fabric.min = 0xFFFFFFFF;
 297         unit->latencies.read.channel.min = 0xFFFFFFFF;
 298         unit->latencies.read.fabric.min = 0xFFFFFFFF;
 299         unit->latencies.cmd.channel.min = 0xFFFFFFFF;
 300         unit->latencies.cmd.fabric.min = 0xFFFFFFFF;
 301
 302         read_lock_irq(&zfcp_data.config_lock);
 303         if (zfcp_get_unit_by_lun(port, fcp_lun)) {
 304                 read_unlock_irq(&zfcp_data.config_lock);
 305                 goto err_out_free;
 306         }
 307         read_unlock_irq(&zfcp_data.config_lock);
 308
 309         if (device_register(&unit->sysfs_device))
 310                 goto err_out_free;
 311
 312         if (sysfs_create_group(&unit->sysfs_device.kobj,
 313                                &zfcp_sysfs_unit_attrs)) {
 314                 device_unregister(&unit->sysfs_device);
 315                 return ERR_PTR(-EIO);
 316         }
 317
 318         zfcp_unit_get(unit);
 319
 320         write_lock_irq(&zfcp_data.config_lock);
 321         list_add_tail(&unit->list, &port->unit_list_head);
 322         atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &unit->status);
 323         atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &unit->status);
 324
 325         write_unlock_irq(&zfcp_data.config_lock);
 326
 327         zfcp_port_get(port);
 328
 329         return unit;
 330
 331 err_out_free:
 332         kfree(unit);
 333         return ERR_PTR(-EINVAL);
 334 }
 335
 336 /**
 337  * zfcp_unit_dequeue - dequeue unit
 338  * @unit: pointer to zfcp_unit
 339  *
 340  * waits until all work is done on unit and removes it then from the unit->list
 341  * of the associated port.
 342  */
 343 void zfcp_unit_dequeue(struct zfcp_unit *unit)
 344 {
 345         wait_event(unit->remove_wq, atomic_read(&unit->refcount) == 0);
 346         write_lock_irq(&zfcp_data.config_lock);
 347         list_del(&unit->list);
 348         write_unlock_irq(&zfcp_data.config_lock);
 349         zfcp_port_put(unit->port);
 350         sysfs_remove_group(&unit->sysfs_device.kobj, &zfcp_sysfs_unit_attrs);
 351         device_unregister(&unit->sysfs_device);
 352 }
 353
 354 static int zfcp_allocate_low_mem_buffers(struct zfcp_adapter *adapter)
 355 {
 356         /* must only be called with zfcp_data.config_sema taken */
 357         adapter->pool.fsf_req_erp =
 358                 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
 359         if (!adapter->pool.fsf_req_erp)
 360                 return -ENOMEM;
 361
 362         adapter->pool.fsf_req_scsi =
 363                 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
 364         if (!adapter->pool.fsf_req_scsi)
 365                 return -ENOMEM;
 366
 367         adapter->pool.fsf_req_abort =
 368                 mempool_create_slab_pool(1, zfcp_data.fsf_req_qtcb_cache);
 369         if (!adapter->pool.fsf_req_abort)
 370                 return -ENOMEM;
 371
 372         adapter->pool.fsf_req_status_read =
 373                 mempool_create_kmalloc_pool(FSF_STATUS_READS_RECOM,
 374                                             sizeof(struct zfcp_fsf_req));
 375         if (!adapter->pool.fsf_req_status_read)
 376                 return -ENOMEM;
 377
 378         adapter->pool.data_status_read =
 379                 mempool_create_slab_pool(FSF_STATUS_READS_RECOM,
 380                                          zfcp_data.sr_buffer_cache);
 381         if (!adapter->pool.data_status_read)
 382                 return -ENOMEM;
 383
 384         adapter->pool.data_gid_pn =
 385                 mempool_create_slab_pool(1, zfcp_data.gid_pn_cache);
 386         if (!adapter->pool.data_gid_pn)
 387                 return -ENOMEM;
 388
 389         return 0;
 390 }
 391
 392 static void zfcp_free_low_mem_buffers(struct zfcp_adapter *adapter)
 393 {
 394         /* zfcp_data.config_sema must be held */
 395         if (adapter->pool.fsf_req_erp)
 396                 mempool_destroy(adapter->pool.fsf_req_erp);
 397         if (adapter->pool.fsf_req_scsi)
 398                 mempool_destroy(adapter->pool.fsf_req_scsi);
 399         if (adapter->pool.fsf_req_abort)
 400                 mempool_destroy(adapter->pool.fsf_req_abort);
 401         if (adapter->pool.fsf_req_status_read)
 402                 mempool_destroy(adapter->pool.fsf_req_status_read);
 403         if (adapter->pool.data_status_read)
 404                 mempool_destroy(adapter->pool.data_status_read);
 405         if (adapter->pool.data_gid_pn)
 406                 mempool_destroy(adapter->pool.data_gid_pn);
 407 }
 408
 409 /**
 410  * zfcp_status_read_refill - refill the long running status_read_requests
 411  * @adapter: ptr to struct zfcp_adapter for which the buffers should be refilled
 412  *
 413  * Returns: 0 on success, 1 otherwise
 414  *
 415  * if there are 16 or more status_read requests missing an adapter_reopen
 416  * is triggered
 417  */
 418 int zfcp_status_read_refill(struct zfcp_adapter *adapter)
 419 {
 420         while (atomic_read(&adapter->stat_miss) > 0)
 421                 if (zfcp_fsf_status_read(adapter)) {
 422                         if (atomic_read(&adapter->stat_miss) >= 16) {
 423                                 zfcp_erp_adapter_reopen(adapter, 0, "axsref1",
 424                                                         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 static void zfcp_print_sl(struct seq_file *m, struct service_level *sl)
 440 {
 441         struct zfcp_adapter *adapter =
 442                 container_of(sl, struct zfcp_adapter, service_level);
 443
 444         seq_printf(m, "zfcp: %s microcode level %x\n",
 445                    dev_name(&adapter->ccw_device->dev),
 446                    adapter->fsf_lic_version);
 447 }
 448
 449 /**
 450  * zfcp_adapter_enqueue - enqueue a new adapter to the list
 451  * @ccw_device: pointer to the struct cc_device
 452  *
 453  * Returns:     0             if a new adapter was successfully enqueued
 454  *              -ENOMEM       if alloc failed
 455  * Enqueues an adapter at the end of the adapter list in the driver data.
 456  * All adapter internal structures are set up.
 457  * Proc-fs entries are also created.
 458  * locks:       config_sema must be held to serialise changes to the adapter list
 459  */
 460 int zfcp_adapter_enqueue(struct ccw_device *ccw_device)
 461 {
 462         struct zfcp_adapter *adapter;
 463
 464         /*
 465          * Note: It is safe to release the list_lock, as any list changes
 466          * are protected by the config_sema, which must be held to get here
 467          */
 468
 469         adapter = kzalloc(sizeof(struct zfcp_adapter), GFP_KERNEL);
 470         if (!adapter)
 471                 return -ENOMEM;
 472
 473         ccw_device->handler = NULL;
 474         adapter->ccw_device = ccw_device;
 475         atomic_set(&adapter->refcount, 0);
 476
 477         if (zfcp_qdio_allocate(adapter))
 478                 goto qdio_allocate_failed;
 479
 480         if (zfcp_allocate_low_mem_buffers(adapter))
 481                 goto failed_low_mem_buffers;
 482
 483         if (zfcp_reqlist_alloc(adapter))
 484                 goto failed_low_mem_buffers;
 485
 486         if (zfcp_adapter_debug_register(adapter))
 487                 goto debug_register_failed;
 488
 489         init_waitqueue_head(&adapter->remove_wq);
 490         init_waitqueue_head(&adapter->erp_thread_wqh);
 491         init_waitqueue_head(&adapter->erp_done_wqh);
 492
 493         INIT_LIST_HEAD(&adapter->port_list_head);
 494         INIT_LIST_HEAD(&adapter->erp_ready_head);
 495         INIT_LIST_HEAD(&adapter->erp_running_head);
 496
 497         spin_lock_init(&adapter->req_list_lock);
 498
 499         spin_lock_init(&adapter->hba_dbf_lock);
 500         spin_lock_init(&adapter->san_dbf_lock);
 501         spin_lock_init(&adapter->scsi_dbf_lock);
 502         spin_lock_init(&adapter->rec_dbf_lock);
 503         spin_lock_init(&adapter->req_q_lock);
 504         spin_lock_init(&adapter->qdio_stat_lock);
 505
 506         rwlock_init(&adapter->erp_lock);
 507         rwlock_init(&adapter->abort_lock);
 508
 509         sema_init(&adapter->erp_ready_sem, 0);
 510
 511         INIT_WORK(&adapter->stat_work, _zfcp_status_read_scheduler);
 512         INIT_WORK(&adapter->scan_work, _zfcp_scan_ports_later);
 513
 514         adapter->service_level.seq_print = zfcp_print_sl;
 515
 516         /* mark adapter unusable as long as sysfs registration is not complete */
 517         atomic_set_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
 518
 519         dev_set_drvdata(&ccw_device->dev, adapter);
 520
 521         if (sysfs_create_group(&ccw_device->dev.kobj,
 522                                &zfcp_sysfs_adapter_attrs))
 523                 goto sysfs_failed;
 524
 525         atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &adapter->status);
 526
 527         zfcp_fc_nameserver_init(adapter);
 528
 529         if (!zfcp_adapter_scsi_register(adapter))
 530                 return 0;
 531
 532 sysfs_failed:
 533         zfcp_adapter_debug_unregister(adapter);
 534 debug_register_failed:
 535         dev_set_drvdata(&ccw_device->dev, NULL);
 536         kfree(adapter->req_list);
 537 failed_low_mem_buffers:
 538         zfcp_free_low_mem_buffers(adapter);
 539 qdio_allocate_failed:
 540         zfcp_qdio_free(adapter);
 541         kfree(adapter);
 542         return -ENOMEM;
 543 }
 544
 545 /**
 546  * zfcp_adapter_dequeue - remove the adapter from the resource list
 547  * @adapter: pointer to struct zfcp_adapter which should be removed
 548  * locks:       adapter list write lock is assumed to be held by caller
 549  */
 550 void zfcp_adapter_dequeue(struct zfcp_adapter *adapter)
 551 {
 552         int retval = 0;
 553         unsigned long flags;
 554
 555         cancel_work_sync(&adapter->scan_work);
 556         cancel_work_sync(&adapter->stat_work);
 557         zfcp_adapter_scsi_unregister(adapter);
 558         sysfs_remove_group(&adapter->ccw_device->dev.kobj,
 559                            &zfcp_sysfs_adapter_attrs);
 560         dev_set_drvdata(&adapter->ccw_device->dev, NULL);
 561         /* sanity check: no pending FSF requests */
 562         spin_lock_irqsave(&adapter->req_list_lock, flags);
 563         retval = zfcp_reqlist_isempty(adapter);
 564         spin_unlock_irqrestore(&adapter->req_list_lock, flags);
 565         if (!retval)
 566                 return;
 567
 568         zfcp_adapter_debug_unregister(adapter);
 569         zfcp_qdio_free(adapter);
 570         zfcp_free_low_mem_buffers(adapter);
 571         kfree(adapter->req_list);
 572         kfree(adapter->fc_stats);
 573         kfree(adapter->stats_reset_data);
 574         kfree(adapter);
 575 }
 576
 577 static void zfcp_sysfs_port_release(struct device *dev)
 578 {
 579         kfree(container_of(dev, struct zfcp_port, sysfs_device));
 580 }
 581
 582 /**
 583  * zfcp_port_enqueue - enqueue port to port list of adapter
 584  * @adapter: adapter where remote port is added
 585  * @wwpn: WWPN of the remote port to be enqueued
 586  * @status: initial status for the port
 587  * @d_id: destination id of the remote port to be enqueued
 588  * Returns: pointer to enqueued port on success, ERR_PTR on error
 589  * Locks: config_sema must be held to serialize changes to the port list
 590  *
 591  * All port internal structures are set up and the sysfs entry is generated.
 592  * d_id is used to enqueue ports with a well known address like the Directory
 593  * Service for nameserver lookup.
 594  */
 595 struct zfcp_port *zfcp_port_enqueue(struct zfcp_adapter *adapter, u64 wwpn,
 596                                      u32 status, u32 d_id)
 597 {
 598         struct zfcp_port *port;
 599         int retval;
 600
 601         port = kzalloc(sizeof(struct zfcp_port), GFP_KERNEL);
 602         if (!port)
 603                 return ERR_PTR(-ENOMEM);
 604
 605         init_waitqueue_head(&port->remove_wq);
 606         INIT_LIST_HEAD(&port->unit_list_head);
 607         INIT_WORK(&port->gid_pn_work, zfcp_erp_port_strategy_open_lookup);
 608         INIT_WORK(&port->test_link_work, zfcp_fc_link_test_work);
 609         INIT_WORK(&port->rport_work, zfcp_scsi_rport_work);
 610
 611         port->adapter = adapter;
 612         port->d_id = d_id;
 613         port->wwpn = wwpn;
 614         port->rport_task = RPORT_NONE;
 615
 616         /* mark port unusable as long as sysfs registration is not complete */
 617         atomic_set_mask(status | ZFCP_STATUS_COMMON_REMOVE, &port->status);
 618         atomic_set(&port->refcount, 0);
 619
 620         dev_set_name(&port->sysfs_device, "0x%016llx",
 621                      (unsigned long long)wwpn);
 622         port->sysfs_device.parent = &adapter->ccw_device->dev;
 623
 624         port->sysfs_device.release = zfcp_sysfs_port_release;
 625         dev_set_drvdata(&port->sysfs_device, port);
 626
 627         read_lock_irq(&zfcp_data.config_lock);
 628         if (zfcp_get_port_by_wwpn(adapter, wwpn)) {
 629                 read_unlock_irq(&zfcp_data.config_lock);
 630                 goto err_out_free;
 631         }
 632         read_unlock_irq(&zfcp_data.config_lock);
 633
 634         if (device_register(&port->sysfs_device))
 635                 goto err_out_free;
 636
 637         retval = sysfs_create_group(&port->sysfs_device.kobj,
 638                                     &zfcp_sysfs_port_attrs);
 639
 640         if (retval) {
 641                 device_unregister(&port->sysfs_device);
 642                 goto err_out;
 643         }
 644
 645         zfcp_port_get(port);
 646
 647         write_lock_irq(&zfcp_data.config_lock);
 648         list_add_tail(&port->list, &adapter->port_list_head);
 649         atomic_clear_mask(ZFCP_STATUS_COMMON_REMOVE, &port->status);
 650         atomic_set_mask(ZFCP_STATUS_COMMON_RUNNING, &port->status);
 651
 652         write_unlock_irq(&zfcp_data.config_lock);
 653
 654         zfcp_adapter_get(adapter);
 655         return port;
 656
 657 err_out_free:
 658         kfree(port);
 659 err_out:
 660         return ERR_PTR(-EINVAL);
 661 }
 662
 663 /**
 664  * zfcp_port_dequeue - dequeues a port from the port list of the adapter
 665  * @port: pointer to struct zfcp_port which should be removed
 666  */
 667 void zfcp_port_dequeue(struct zfcp_port *port)
 668 {
 669         wait_event(port->remove_wq, atomic_read(&port->refcount) == 0);
 670         write_lock_irq(&zfcp_data.config_lock);
 671         list_del(&port->list);
 672         write_unlock_irq(&zfcp_data.config_lock);
 673         if (port->rport)
 674                 port->rport->dd_data = NULL;
 675         zfcp_adapter_put(port->adapter);
 676         sysfs_remove_group(&port->sysfs_device.kobj, &zfcp_sysfs_port_attrs);
 677         device_unregister(&port->sysfs_device);
 678 }
 679
 680 /**
 681  * zfcp_sg_free_table - free memory used by scatterlists
 682  * @sg: pointer to scatterlist
 683  * @count: number of scatterlist which are to be free'ed
 684  * the scatterlist are expected to reference pages always
 685  */
 686 void zfcp_sg_free_table(struct scatterlist *sg, int count)
 687 {
 688         int i;
 689
 690         for (i = 0; i < count; i++, sg++)
 691                 if (sg)
 692                         free_page((unsigned long) sg_virt(sg));
 693                 else
 694                         break;
 695 }
 696
 697 /**
 698  * zfcp_sg_setup_table - init scatterlist and allocate, assign buffers
 699  * @sg: pointer to struct scatterlist
 700  * @count: number of scatterlists which should be assigned with buffers
 701  * of size page
 702  *
 703  * Returns: 0 on success, -ENOMEM otherwise
 704  */
 705 int zfcp_sg_setup_table(struct scatterlist *sg, int count)
 706 {
 707         void *addr;
 708         int i;
 709
 710         sg_init_table(sg, count);
 711         for (i = 0; i < count; i++, sg++) {
 712                 addr = (void *) get_zeroed_page(GFP_KERNEL);
 713                 if (!addr) {
 714                         zfcp_sg_free_table(sg, i);
 715                         return -ENOMEM;
 716                 }
 717                 sg_set_buf(sg, addr, PAGE_SIZE);
 718         }
 719         return 0;
 720 }