drivers/s390/scsi/zfcp_fc.c

   1 /*
   2  * zfcp device driver
   3  *
   4  * Fibre Channel related functions for the zfcp device driver.
   5  *
   6  * Copyright IBM Corporation 2008
   7  */
   8
   9 #define KMSG_COMPONENT "zfcp"
  10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
  11
  12 #include "zfcp_ext.h"
  13
  14 enum rscn_address_format {
  15         RSCN_PORT_ADDRESS       = 0x0,
  16         RSCN_AREA_ADDRESS       = 0x1,
  17         RSCN_DOMAIN_ADDRESS     = 0x2,
  18         RSCN_FABRIC_ADDRESS     = 0x3,
  19 };
  20
  21 static u32 rscn_range_mask[] = {
  22         [RSCN_PORT_ADDRESS]             = 0xFFFFFF,
  23         [RSCN_AREA_ADDRESS]             = 0xFFFF00,
  24         [RSCN_DOMAIN_ADDRESS]           = 0xFF0000,
  25         [RSCN_FABRIC_ADDRESS]           = 0x000000,
  26 };
  27
  28 struct ct_iu_gpn_ft_req {
  29         struct ct_hdr header;
  30         u8 flags;
  31         u8 domain_id_scope;
  32         u8 area_id_scope;
  33         u8 fc4_type;
  34 } __attribute__ ((packed));
  35
  36 struct gpn_ft_resp_acc {
  37         u8 control;
  38         u8 port_id[3];
  39         u8 reserved[4];
  40         u64 wwpn;
  41 } __attribute__ ((packed));
  42
  43 #define ZFCP_CT_SIZE_ONE_PAGE   (PAGE_SIZE - sizeof(struct ct_hdr))
  44 #define ZFCP_GPN_FT_ENTRIES     (ZFCP_CT_SIZE_ONE_PAGE \
  45                                         / sizeof(struct gpn_ft_resp_acc))
  46 #define ZFCP_GPN_FT_BUFFERS 4
  47 #define ZFCP_GPN_FT_MAX_SIZE (ZFCP_GPN_FT_BUFFERS * PAGE_SIZE \
  48                                 - sizeof(struct ct_hdr))
  49 #define ZFCP_GPN_FT_MAX_ENTRIES ZFCP_GPN_FT_BUFFERS * (ZFCP_GPN_FT_ENTRIES + 1)
  50
  51 struct ct_iu_gpn_ft_resp {
  52         struct ct_hdr header;
  53         struct gpn_ft_resp_acc accept[ZFCP_GPN_FT_ENTRIES];
  54 } __attribute__ ((packed));
  55
  56 struct zfcp_gpn_ft {
  57         struct zfcp_send_ct ct;
  58         struct scatterlist sg_req;
  59         struct scatterlist sg_resp[ZFCP_GPN_FT_BUFFERS];
  60 };
  61
  62 struct zfcp_fc_ns_handler_data {
  63         struct completion done;
  64         void (*handler)(unsigned long);
  65         unsigned long handler_data;
  66 };
  67
  68 static int zfcp_wka_port_get(struct zfcp_wka_port *wka_port)
  69 {
  70         if (mutex_lock_interruptible(&wka_port->mutex))
  71                 return -ERESTARTSYS;
  72
  73         if (wka_port->status == ZFCP_WKA_PORT_OFFLINE ||
  74             wka_port->status == ZFCP_WKA_PORT_CLOSING) {
  75                 wka_port->status = ZFCP_WKA_PORT_OPENING;
  76                 if (zfcp_fsf_open_wka_port(wka_port))
  77                         wka_port->status = ZFCP_WKA_PORT_OFFLINE;
  78         }
  79
  80         mutex_unlock(&wka_port->mutex);
  81
  82         wait_event_timeout(
  83                 wka_port->completion_wq,
  84                 wka_port->status == ZFCP_WKA_PORT_ONLINE ||
  85                 wka_port->status == ZFCP_WKA_PORT_OFFLINE,
  86                 HZ >> 1);
  87
  88         if (wka_port->status == ZFCP_WKA_PORT_ONLINE) {
  89                 atomic_inc(&wka_port->refcount);
  90                 return 0;
  91         }
  92         return -EIO;
  93 }
  94
  95 static void zfcp_wka_port_offline(struct work_struct *work)
  96 {
  97         struct delayed_work *dw = container_of(work, struct delayed_work, work);
  98         struct zfcp_wka_port *wka_port =
  99                         container_of(dw, struct zfcp_wka_port, work);
 100
 101         wait_event(wka_port->completion_wq,
 102                         atomic_read(&wka_port->refcount) == 0);
 103
 104         mutex_lock(&wka_port->mutex);
 105         if ((atomic_read(&wka_port->refcount) != 0) ||
 106             (wka_port->status != ZFCP_WKA_PORT_ONLINE))
 107                 goto out;
 108
 109         wka_port->status = ZFCP_WKA_PORT_CLOSING;
 110         if (zfcp_fsf_close_wka_port(wka_port)) {
 111                 wka_port->status = ZFCP_WKA_PORT_OFFLINE;
 112                 wake_up(&wka_port->completion_wq);
 113         }
 114 out:
 115         mutex_unlock(&wka_port->mutex);
 116 }
 117
 118 static void zfcp_wka_port_put(struct zfcp_wka_port *wka_port)
 119 {
 120         if (atomic_dec_return(&wka_port->refcount) != 0)
 121                 return;
 122         /* wait 10 miliseconds, other reqs might pop in */
 123         schedule_delayed_work(&wka_port->work, HZ / 100);
 124 }
 125
 126 void zfcp_fc_nameserver_init(struct zfcp_adapter *adapter)
 127 {
 128         struct zfcp_wka_port *wka_port = &adapter->nsp;
 129
 130         init_waitqueue_head(&wka_port->completion_wq);
 131
 132         wka_port->adapter = adapter;
 133         wka_port->d_id = ZFCP_DID_DIRECTORY_SERVICE;
 134
 135         wka_port->status = ZFCP_WKA_PORT_OFFLINE;
 136         atomic_set(&wka_port->refcount, 0);
 137         mutex_init(&wka_port->mutex);
 138         INIT_DELAYED_WORK(&wka_port->work, zfcp_wka_port_offline);
 139 }
 140
 141 static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
 142                                    struct fcp_rscn_element *elem)
 143 {
 144         unsigned long flags;
 145         struct zfcp_port *port;
 146
 147         read_lock_irqsave(&zfcp_data.config_lock, flags);
 148         list_for_each_entry(port, &fsf_req->adapter->port_list_head, list)
 149                 if ((port->d_id & range) == (elem->nport_did & range))
 150                         zfcp_test_link(port);
 151
 152         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
 153 }
 154
 155 static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
 156 {
 157         struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
 158         struct fcp_rscn_head *fcp_rscn_head;
 159         struct fcp_rscn_element *fcp_rscn_element;
 160         u16 i;
 161         u16 no_entries;
 162         u32 range_mask;
 163
 164         fcp_rscn_head = (struct fcp_rscn_head *) status_buffer->payload.data;
 165         fcp_rscn_element = (struct fcp_rscn_element *) fcp_rscn_head;
 166
 167         /* see FC-FS */
 168         no_entries = fcp_rscn_head->payload_len /
 169                         sizeof(struct fcp_rscn_element);
 170
 171         for (i = 1; i < no_entries; i++) {
 172                 /* skip head and start with 1st element */
 173                 fcp_rscn_element++;
 174                 range_mask = rscn_range_mask[fcp_rscn_element->addr_format];
 175                 _zfcp_fc_incoming_rscn(fsf_req, range_mask, fcp_rscn_element);
 176         }
 177         schedule_work(&fsf_req->adapter->scan_work);
 178 }
 179
 180 static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
 181 {
 182         struct zfcp_adapter *adapter = req->adapter;
 183         struct zfcp_port *port;
 184         unsigned long flags;
 185
 186         read_lock_irqsave(&zfcp_data.config_lock, flags);
 187         list_for_each_entry(port, &adapter->port_list_head, list)
 188                 if (port->wwpn == wwpn)
 189                         break;
 190         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
 191
 192         if (port && (port->wwpn == wwpn))
 193                 zfcp_erp_port_forced_reopen(port, 0, "fciwwp1", req);
 194 }
 195
 196 static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
 197 {
 198         struct fsf_status_read_buffer *status_buffer =
 199                 (struct fsf_status_read_buffer *)req->data;
 200         struct fsf_plogi *els_plogi =
 201                 (struct fsf_plogi *) status_buffer->payload.data;
 202
 203         zfcp_fc_incoming_wwpn(req, els_plogi->serv_param.wwpn);
 204 }
 205
 206 static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
 207 {
 208         struct fsf_status_read_buffer *status_buffer =
 209                 (struct fsf_status_read_buffer *)req->data;
 210         struct fcp_logo *els_logo =
 211                 (struct fcp_logo *) status_buffer->payload.data;
 212
 213         zfcp_fc_incoming_wwpn(req, els_logo->nport_wwpn);
 214 }
 215
 216 /**
 217  * zfcp_fc_incoming_els - handle incoming ELS
 218  * @fsf_req - request which contains incoming ELS
 219  */
 220 void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
 221 {
 222         struct fsf_status_read_buffer *status_buffer =
 223                 (struct fsf_status_read_buffer *) fsf_req->data;
 224         unsigned int els_type = status_buffer->payload.data[0];
 225
 226         zfcp_san_dbf_event_incoming_els(fsf_req);
 227         if (els_type == LS_PLOGI)
 228                 zfcp_fc_incoming_plogi(fsf_req);
 229         else if (els_type == LS_LOGO)
 230                 zfcp_fc_incoming_logo(fsf_req);
 231         else if (els_type == LS_RSCN)
 232                 zfcp_fc_incoming_rscn(fsf_req);
 233 }
 234
 235 static void zfcp_fc_ns_handler(unsigned long data)
 236 {
 237         struct zfcp_fc_ns_handler_data *compl_rec =
 238                         (struct zfcp_fc_ns_handler_data *) data;
 239
 240         if (compl_rec->handler)
 241                 compl_rec->handler(compl_rec->handler_data);
 242
 243         complete(&compl_rec->done);
 244 }
 245
 246 static void zfcp_fc_ns_gid_pn_eval(unsigned long data)
 247 {
 248         struct zfcp_gid_pn_data *gid_pn = (struct zfcp_gid_pn_data *) data;
 249         struct zfcp_send_ct *ct = &gid_pn->ct;
 250         struct ct_iu_gid_pn_req *ct_iu_req = sg_virt(ct->req);
 251         struct ct_iu_gid_pn_resp *ct_iu_resp = sg_virt(ct->resp);
 252         struct zfcp_port *port = gid_pn->port;
 253
 254         if (ct->status)
 255                 return;
 256         if (ct_iu_resp->header.cmd_rsp_code != ZFCP_CT_ACCEPT)
 257                 return;
 258
 259         /* paranoia */
 260         if (ct_iu_req->wwpn != port->wwpn)
 261                 return;
 262         /* looks like a valid d_id */
 263         port->d_id = ct_iu_resp->d_id & ZFCP_DID_MASK;
 264 }
 265
 266 int static zfcp_fc_ns_gid_pn_request(struct zfcp_erp_action *erp_action,
 267                                      struct zfcp_gid_pn_data *gid_pn)
 268 {
 269         struct zfcp_adapter *adapter = erp_action->adapter;
 270         struct zfcp_fc_ns_handler_data compl_rec;
 271         int ret;
 272
 273         /* setup parameters for send generic command */
 274         gid_pn->port = erp_action->port;
 275         gid_pn->ct.wka_port = &adapter->nsp;
 276         gid_pn->ct.handler = zfcp_fc_ns_handler;
 277         gid_pn->ct.handler_data = (unsigned long) &compl_rec;
 278         gid_pn->ct.timeout = ZFCP_NS_GID_PN_TIMEOUT;
 279         gid_pn->ct.req = &gid_pn->req;
 280         gid_pn->ct.resp = &gid_pn->resp;
 281         sg_init_one(&gid_pn->req, &gid_pn->ct_iu_req,
 282                     sizeof(struct ct_iu_gid_pn_req));
 283         sg_init_one(&gid_pn->resp, &gid_pn->ct_iu_resp,
 284                     sizeof(struct ct_iu_gid_pn_resp));
 285
 286         /* setup nameserver request */
 287         gid_pn->ct_iu_req.header.revision = ZFCP_CT_REVISION;
 288         gid_pn->ct_iu_req.header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
 289         gid_pn->ct_iu_req.header.gs_subtype = ZFCP_CT_NAME_SERVER;
 290         gid_pn->ct_iu_req.header.options = ZFCP_CT_SYNCHRONOUS;
 291         gid_pn->ct_iu_req.header.cmd_rsp_code = ZFCP_CT_GID_PN;
 292         gid_pn->ct_iu_req.header.max_res_size = ZFCP_CT_SIZE_ONE_PAGE / 4;
 293         gid_pn->ct_iu_req.wwpn = erp_action->port->wwpn;
 294
 295         init_completion(&compl_rec.done);
 296         compl_rec.handler = zfcp_fc_ns_gid_pn_eval;
 297         compl_rec.handler_data = (unsigned long) gid_pn;
 298         ret = zfcp_fsf_send_ct(&gid_pn->ct, adapter->pool.fsf_req_erp,
 299                                erp_action);
 300         if (!ret)
 301                 wait_for_completion(&compl_rec.done);
 302         return ret;
 303 }
 304
 305 /**
 306  * zfcp_fc_ns_gid_pn_request - initiate GID_PN nameserver request
 307  * @erp_action: pointer to zfcp_erp_action where GID_PN request is needed
 308  * return: -ENOMEM on error, 0 otherwise
 309  */
 310 int zfcp_fc_ns_gid_pn(struct zfcp_erp_action *erp_action)
 311 {
 312         int ret;
 313         struct zfcp_gid_pn_data *gid_pn;
 314         struct zfcp_adapter *adapter = erp_action->adapter;
 315
 316         gid_pn = mempool_alloc(adapter->pool.data_gid_pn, GFP_ATOMIC);
 317         if (!gid_pn)
 318                 return -ENOMEM;
 319
 320         memset(gid_pn, 0, sizeof(*gid_pn));
 321
 322         ret = zfcp_wka_port_get(&adapter->nsp);
 323         if (ret)
 324                 goto out;
 325
 326         ret = zfcp_fc_ns_gid_pn_request(erp_action, gid_pn);
 327
 328         zfcp_wka_port_put(&adapter->nsp);
 329 out:
 330         mempool_free(gid_pn, adapter->pool.data_gid_pn);
 331         return ret;
 332 }
 333
 334 /**
 335  * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
 336  * @port: zfcp_port structure
 337  * @plogi: plogi payload
 338  *
 339  * Evaluate PLOGI playload and copy important fields into zfcp_port structure
 340  */
 341 void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fsf_plogi *plogi)
 342 {
 343         port->maxframe_size = plogi->serv_param.common_serv_param[7] |
 344                 ((plogi->serv_param.common_serv_param[6] & 0x0F) << 8);
 345         if (plogi->serv_param.class1_serv_param[0] & 0x80)
 346                 port->supported_classes |= FC_COS_CLASS1;
 347         if (plogi->serv_param.class2_serv_param[0] & 0x80)
 348                 port->supported_classes |= FC_COS_CLASS2;
 349         if (plogi->serv_param.class3_serv_param[0] & 0x80)
 350                 port->supported_classes |= FC_COS_CLASS3;
 351         if (plogi->serv_param.class4_serv_param[0] & 0x80)
 352                 port->supported_classes |= FC_COS_CLASS4;
 353 }
 354
 355 struct zfcp_els_adisc {
 356         struct zfcp_send_els els;
 357         struct scatterlist req;
 358         struct scatterlist resp;
 359         struct zfcp_ls_adisc ls_adisc;
 360         struct zfcp_ls_adisc ls_adisc_acc;
 361 };
 362
 363 static void zfcp_fc_adisc_handler(unsigned long data)
 364 {
 365         struct zfcp_els_adisc *adisc = (struct zfcp_els_adisc *) data;
 366         struct zfcp_port *port = adisc->els.port;
 367         struct zfcp_ls_adisc *ls_adisc = &adisc->ls_adisc_acc;
 368
 369         if (adisc->els.status) {
 370                 /* request rejected or timed out */
 371                 zfcp_erp_port_forced_reopen(port, 0, "fcadh_1", NULL);
 372                 goto out;
 373         }
 374
 375         if (!port->wwnn)
 376                 port->wwnn = ls_adisc->wwnn;
 377
 378         if ((port->wwpn != ls_adisc->wwpn) ||
 379             !(atomic_read(&port->status) & ZFCP_STATUS_COMMON_OPEN))
 380                 zfcp_erp_port_reopen(port, ZFCP_STATUS_COMMON_ERP_FAILED,
 381                                      "fcadh_2", NULL);
 382
 383  out:
 384         zfcp_port_put(port);
 385         kfree(adisc);
 386 }
 387
 388 static int zfcp_fc_adisc(struct zfcp_port *port)
 389 {
 390         struct zfcp_els_adisc *adisc;
 391         struct zfcp_adapter *adapter = port->adapter;
 392
 393         adisc = kzalloc(sizeof(struct zfcp_els_adisc), GFP_ATOMIC);
 394         if (!adisc)
 395                 return -ENOMEM;
 396
 397         adisc->els.req = &adisc->req;
 398         adisc->els.resp = &adisc->resp;
 399         sg_init_one(adisc->els.req, &adisc->ls_adisc,
 400                     sizeof(struct zfcp_ls_adisc));
 401         sg_init_one(adisc->els.resp, &adisc->ls_adisc_acc,
 402                     sizeof(struct zfcp_ls_adisc));
 403
 404         adisc->els.adapter = adapter;
 405         adisc->els.port = port;
 406         adisc->els.d_id = port->d_id;
 407         adisc->els.handler = zfcp_fc_adisc_handler;
 408         adisc->els.handler_data = (unsigned long) adisc;
 409         adisc->els.ls_code = adisc->ls_adisc.code = ZFCP_LS_ADISC;
 410
 411         /* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
 412            without FC-AL-2 capability, so we don't set it */
 413         adisc->ls_adisc.wwpn = fc_host_port_name(adapter->scsi_host);
 414         adisc->ls_adisc.wwnn = fc_host_node_name(adapter->scsi_host);
 415         adisc->ls_adisc.nport_id = fc_host_port_id(adapter->scsi_host);
 416
 417         return zfcp_fsf_send_els(&adisc->els);
 418 }
 419
 420 void zfcp_fc_link_test_work(struct work_struct *work)
 421 {
 422         struct zfcp_port *port =
 423                 container_of(work, struct zfcp_port, test_link_work);
 424         int retval;
 425
 426         retval = zfcp_fc_adisc(port);
 427         if (retval == 0)
 428                 return;
 429
 430         /* send of ADISC was not possible */
 431         zfcp_port_put(port);
 432         if (retval != -EBUSY)
 433                 zfcp_erp_port_forced_reopen(port, 0, "fcltwk1", NULL);
 434 }
 435
 436 /**
 437  * zfcp_test_link - lightweight link test procedure
 438  * @port: port to be tested
 439  *
 440  * Test status of a link to a remote port using the ELS command ADISC.
 441  * If there is a problem with the remote port, error recovery steps
 442  * will be triggered.
 443  */
 444 void zfcp_test_link(struct zfcp_port *port)
 445 {
 446         zfcp_port_get(port);
 447         if (!queue_work(zfcp_data.work_queue, &port->test_link_work))
 448                 zfcp_port_put(port);
 449 }
 450
 451 static void zfcp_free_sg_env(struct zfcp_gpn_ft *gpn_ft, int buf_num)
 452 {
 453         struct scatterlist *sg = &gpn_ft->sg_req;
 454
 455         kfree(sg_virt(sg)); /* free request buffer */
 456         zfcp_sg_free_table(gpn_ft->sg_resp, buf_num);
 457
 458         kfree(gpn_ft);
 459 }
 460
 461 static struct zfcp_gpn_ft *zfcp_alloc_sg_env(int buf_num)
 462 {
 463         struct zfcp_gpn_ft *gpn_ft;
 464         struct ct_iu_gpn_ft_req *req;
 465
 466         gpn_ft = kzalloc(sizeof(*gpn_ft), GFP_KERNEL);
 467         if (!gpn_ft)
 468                 return NULL;
 469
 470         req = kzalloc(sizeof(struct ct_iu_gpn_ft_req), GFP_KERNEL);
 471         if (!req) {
 472                 kfree(gpn_ft);
 473                 gpn_ft = NULL;
 474                 goto out;
 475         }
 476         sg_init_one(&gpn_ft->sg_req, req, sizeof(*req));
 477
 478         if (zfcp_sg_setup_table(gpn_ft->sg_resp, buf_num)) {
 479                 zfcp_free_sg_env(gpn_ft, buf_num);
 480                 gpn_ft = NULL;
 481         }
 482 out:
 483         return gpn_ft;
 484 }
 485
 486
 487 static int zfcp_scan_issue_gpn_ft(struct zfcp_gpn_ft *gpn_ft,
 488                                   struct zfcp_adapter *adapter,
 489                                   int max_bytes)
 490 {
 491         struct zfcp_send_ct *ct = &gpn_ft->ct;
 492         struct ct_iu_gpn_ft_req *req = sg_virt(&gpn_ft->sg_req);
 493         struct zfcp_fc_ns_handler_data compl_rec;
 494         int ret;
 495
 496         /* prepare CT IU for GPN_FT */
 497         req->header.revision = ZFCP_CT_REVISION;
 498         req->header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
 499         req->header.gs_subtype = ZFCP_CT_NAME_SERVER;
 500         req->header.options = ZFCP_CT_SYNCHRONOUS;
 501         req->header.cmd_rsp_code = ZFCP_CT_GPN_FT;
 502         req->header.max_res_size = max_bytes / 4;
 503         req->flags = 0;
 504         req->domain_id_scope = 0;
 505         req->area_id_scope = 0;
 506         req->fc4_type = ZFCP_CT_SCSI_FCP;
 507
 508         /* prepare zfcp_send_ct */
 509         ct->wka_port = &adapter->nsp;
 510         ct->handler = zfcp_fc_ns_handler;
 511         ct->handler_data = (unsigned long)&compl_rec;
 512         ct->timeout = 10;
 513         ct->req = &gpn_ft->sg_req;
 514         ct->resp = gpn_ft->sg_resp;
 515
 516         init_completion(&compl_rec.done);
 517         compl_rec.handler = NULL;
 518         ret = zfcp_fsf_send_ct(ct, NULL, NULL);
 519         if (!ret)
 520                 wait_for_completion(&compl_rec.done);
 521         return ret;
 522 }
 523
 524 static void zfcp_validate_port(struct zfcp_port *port)
 525 {
 526         struct zfcp_adapter *adapter = port->adapter;
 527
 528         atomic_clear_mask(ZFCP_STATUS_COMMON_NOESC, &port->status);
 529
 530         if ((port->supported_classes != 0) ||
 531             !list_empty(&port->unit_list_head)) {
 532                 zfcp_port_put(port);
 533                 return;
 534         }
 535         zfcp_erp_port_shutdown(port, 0, "fcpval1", NULL);
 536         zfcp_erp_wait(adapter);
 537         zfcp_port_put(port);
 538         zfcp_port_dequeue(port);
 539 }
 540
 541 static int zfcp_scan_eval_gpn_ft(struct zfcp_gpn_ft *gpn_ft, int max_entries)
 542 {
 543         struct zfcp_send_ct *ct = &gpn_ft->ct;
 544         struct scatterlist *sg = gpn_ft->sg_resp;
 545         struct ct_hdr *hdr = sg_virt(sg);
 546         struct gpn_ft_resp_acc *acc = sg_virt(sg);
 547         struct zfcp_adapter *adapter = ct->wka_port->adapter;
 548         struct zfcp_port *port, *tmp;
 549         u32 d_id;
 550         int ret = 0, x, last = 0;
 551
 552         if (ct->status)
 553                 return -EIO;
 554
 555         if (hdr->cmd_rsp_code != ZFCP_CT_ACCEPT) {
 556                 if (hdr->reason_code == ZFCP_CT_UNABLE_TO_PERFORM_CMD)
 557                         return -EAGAIN; /* might be a temporary condition */
 558                 return -EIO;
 559         }
 560
 561         if (hdr->max_res_size) {
 562                 dev_warn(&adapter->ccw_device->dev,
 563                          "The name server reported %d words residual data\n",
 564                          hdr->max_res_size);
 565                 return -E2BIG;
 566         }
 567
 568         down(&zfcp_data.config_sema);
 569
 570         /* first entry is the header */
 571         for (x = 1; x < max_entries && !last; x++) {
 572                 if (x % (ZFCP_GPN_FT_ENTRIES + 1))
 573                         acc++;
 574                 else
 575                         acc = sg_virt(++sg);
 576
 577                 last = acc->control & 0x80;
 578                 d_id = acc->port_id[0] << 16 | acc->port_id[1] << 8 |
 579                        acc->port_id[2];
 580
 581                 /* don't attach ports with a well known address */
 582                 if ((d_id & ZFCP_DID_WKA) == ZFCP_DID_WKA)
 583                         continue;
 584                 /* skip the adapter's port and known remote ports */
 585                 if (acc->wwpn == fc_host_port_name(adapter->scsi_host))
 586                         continue;
 587                 port = zfcp_get_port_by_wwpn(adapter, acc->wwpn);
 588                 if (port) {
 589                         zfcp_port_get(port);
 590                         continue;
 591                 }
 592
 593                 port = zfcp_port_enqueue(adapter, acc->wwpn,
 594                                          ZFCP_STATUS_COMMON_NOESC, d_id);
 595                 if (IS_ERR(port))
 596                         ret = PTR_ERR(port);
 597                 else
 598                         zfcp_erp_port_reopen(port, 0, "fcegpf1", NULL);
 599         }
 600
 601         zfcp_erp_wait(adapter);
 602         list_for_each_entry_safe(port, tmp, &adapter->port_list_head, list)
 603                 zfcp_validate_port(port);
 604         up(&zfcp_data.config_sema);
 605         return ret;
 606 }
 607
 608 /**
 609  * zfcp_scan_ports - scan remote ports and attach new ports
 610  * @adapter: pointer to struct zfcp_adapter
 611  */
 612 int zfcp_scan_ports(struct zfcp_adapter *adapter)
 613 {
 614         int ret, i;
 615         struct zfcp_gpn_ft *gpn_ft;
 616         int chain, max_entries, buf_num, max_bytes;
 617
 618         chain = adapter->adapter_features & FSF_FEATURE_ELS_CT_CHAINED_SBALS;
 619         buf_num = chain ? ZFCP_GPN_FT_BUFFERS : 1;
 620         max_entries = chain ? ZFCP_GPN_FT_MAX_ENTRIES : ZFCP_GPN_FT_ENTRIES;
 621         max_bytes = chain ? ZFCP_GPN_FT_MAX_SIZE : ZFCP_CT_SIZE_ONE_PAGE;
 622
 623         if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT)
 624                 return 0;
 625
 626         ret = zfcp_wka_port_get(&adapter->nsp);
 627         if (ret)
 628                 return ret;
 629
 630         gpn_ft = zfcp_alloc_sg_env(buf_num);
 631         if (!gpn_ft) {
 632                 ret = -ENOMEM;
 633                 goto out;
 634         }
 635
 636         for (i = 0; i < 3; i++) {
 637                 ret = zfcp_scan_issue_gpn_ft(gpn_ft, adapter, max_bytes);
 638                 if (!ret) {
 639                         ret = zfcp_scan_eval_gpn_ft(gpn_ft, max_entries);
 640                         if (ret == -EAGAIN)
 641                                 ssleep(1);
 642                         else
 643                                 break;
 644                 }
 645         }
 646         zfcp_free_sg_env(gpn_ft, buf_num);
 647 out:
 648         zfcp_wka_port_put(&adapter->nsp);
 649         return ret;
 650 }
 651
 652
 653 void _zfcp_scan_ports_later(struct work_struct *work)
 654 {
 655         zfcp_scan_ports(container_of(work, struct zfcp_adapter, scan_work));
 656 }