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