git.oblomov.eu Git - linux-2.6/blob - 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 struct ct_iu_gpn_ft_req {
  15         struct ct_hdr header;
  16         u8 flags;
  17         u8 domain_id_scope;
  18         u8 area_id_scope;
  19         u8 fc4_type;
  20 } __attribute__ ((packed));
  21
  22 struct gpn_ft_resp_acc {
  23         u8 control;
  24         u8 port_id[3];
  25         u8 reserved[4];
  26         u64 wwpn;
  27 } __attribute__ ((packed));
  28
  29 #define ZFCP_GPN_FT_ENTRIES ((PAGE_SIZE - sizeof(struct ct_hdr)) \
  30                                 / sizeof(struct gpn_ft_resp_acc))
  31 #define ZFCP_GPN_FT_BUFFERS 4
  32 #define ZFCP_GPN_FT_MAX_ENTRIES ZFCP_GPN_FT_BUFFERS * (ZFCP_GPN_FT_ENTRIES + 1)
  33
  34 struct ct_iu_gpn_ft_resp {
  35         struct ct_hdr header;
  36         struct gpn_ft_resp_acc accept[ZFCP_GPN_FT_ENTRIES];
  37 } __attribute__ ((packed));
  38
  39 struct zfcp_gpn_ft {
  40         struct zfcp_send_ct ct;
  41         struct scatterlist sg_req;
  42         struct scatterlist sg_resp[ZFCP_GPN_FT_BUFFERS];
  43 };
  44
  45 struct zfcp_fc_ns_handler_data {
  46         struct completion done;
  47         void (*handler)(unsigned long);
  48         unsigned long handler_data;
  49 };
  50
  51 static int zfcp_wka_port_get(struct zfcp_wka_port *wka_port)
  52 {
  53         if (mutex_lock_interruptible(&wka_port->mutex))
  54                 return -ERESTARTSYS;
  55
  56         if (wka_port->status == ZFCP_WKA_PORT_OFFLINE ||
  57             wka_port->status == ZFCP_WKA_PORT_CLOSING) {
  58                 wka_port->status = ZFCP_WKA_PORT_OPENING;
  59                 if (zfcp_fsf_open_wka_port(wka_port))
  60                         wka_port->status = ZFCP_WKA_PORT_OFFLINE;
  61         }
  62
  63         mutex_unlock(&wka_port->mutex);
  64
  65         wait_event_timeout(
  66                 wka_port->completion_wq,
  67                 wka_port->status == ZFCP_WKA_PORT_ONLINE ||
  68                 wka_port->status == ZFCP_WKA_PORT_OFFLINE,
  69                 HZ >> 1);
  70
  71         if (wka_port->status == ZFCP_WKA_PORT_ONLINE) {
  72                 atomic_inc(&wka_port->refcount);
  73                 return 0;
  74         }
  75         return -EIO;
  76 }
  77
  78 static void zfcp_wka_port_offline(struct work_struct *work)
  79 {
  80         struct delayed_work *dw = container_of(work, struct delayed_work, work);
  81         struct zfcp_wka_port *wka_port =
  82                         container_of(dw, struct zfcp_wka_port, work);
  83
  84         wait_event(wka_port->completion_wq,
  85                         atomic_read(&wka_port->refcount) == 0);
  86
  87         mutex_lock(&wka_port->mutex);
  88         if ((atomic_read(&wka_port->refcount) != 0) ||
  89             (wka_port->status != ZFCP_WKA_PORT_ONLINE))
  90                 goto out;
  91
  92         wka_port->status = ZFCP_WKA_PORT_CLOSING;
  93         if (zfcp_fsf_close_wka_port(wka_port)) {
  94                 wka_port->status = ZFCP_WKA_PORT_OFFLINE;
  95                 wake_up(&wka_port->completion_wq);
  96         }
  97 out:
  98         mutex_unlock(&wka_port->mutex);
  99 }
 100
 101 static void zfcp_wka_port_put(struct zfcp_wka_port *wka_port)
 102 {
 103         if (atomic_dec_return(&wka_port->refcount) != 0)
 104                 return;
 105         /* wait 10 miliseconds, other reqs might pop in */
 106         schedule_delayed_work(&wka_port->work, HZ / 100);
 107 }
 108
 109 void zfcp_fc_nameserver_init(struct zfcp_adapter *adapter)
 110 {
 111         struct zfcp_wka_port *wka_port = &adapter->nsp;
 112
 113         init_waitqueue_head(&wka_port->completion_wq);
 114
 115         wka_port->adapter = adapter;
 116         wka_port->d_id = ZFCP_DID_DIRECTORY_SERVICE;
 117
 118         wka_port->status = ZFCP_WKA_PORT_OFFLINE;
 119         atomic_set(&wka_port->refcount, 0);
 120         mutex_init(&wka_port->mutex);
 121         INIT_DELAYED_WORK(&wka_port->work, zfcp_wka_port_offline);
 122 }
 123
 124 static void _zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req, u32 range,
 125                                    struct fcp_rscn_element *elem)
 126 {
 127         unsigned long flags;
 128         struct zfcp_port *port;
 129
 130         read_lock_irqsave(&zfcp_data.config_lock, flags);
 131         list_for_each_entry(port, &fsf_req->adapter->port_list_head, list) {
 132                 if (!(atomic_read(&port->status) & ZFCP_STATUS_PORT_PHYS_OPEN))
 133                         /* Try to connect to unused ports anyway. */
 134                         zfcp_erp_port_reopen(port,
 135                                              ZFCP_STATUS_COMMON_ERP_FAILED,
 136                                              82, fsf_req);
 137                 else if ((port->d_id & range) == (elem->nport_did & range))
 138                         /* Check connection status for connected ports */
 139                         zfcp_test_link(port);
 140         }
 141         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
 142 }
 143
 144 static void zfcp_fc_incoming_rscn(struct zfcp_fsf_req *fsf_req)
 145 {
 146         struct fsf_status_read_buffer *status_buffer = (void *)fsf_req->data;
 147         struct fcp_rscn_head *fcp_rscn_head;
 148         struct fcp_rscn_element *fcp_rscn_element;
 149         u16 i;
 150         u16 no_entries;
 151         u32 range_mask;
 152
 153         fcp_rscn_head = (struct fcp_rscn_head *) status_buffer->payload.data;
 154         fcp_rscn_element = (struct fcp_rscn_element *) fcp_rscn_head;
 155
 156         /* see FC-FS */
 157         no_entries = fcp_rscn_head->payload_len /
 158                         sizeof(struct fcp_rscn_element);
 159
 160         for (i = 1; i < no_entries; i++) {
 161                 /* skip head and start with 1st element */
 162                 fcp_rscn_element++;
 163                 switch (fcp_rscn_element->addr_format) {
 164                 case ZFCP_PORT_ADDRESS:
 165                         range_mask = ZFCP_PORTS_RANGE_PORT;
 166                         break;
 167                 case ZFCP_AREA_ADDRESS:
 168                         range_mask = ZFCP_PORTS_RANGE_AREA;
 169                         break;
 170                 case ZFCP_DOMAIN_ADDRESS:
 171                         range_mask = ZFCP_PORTS_RANGE_DOMAIN;
 172                         break;
 173                 case ZFCP_FABRIC_ADDRESS:
 174                         range_mask = ZFCP_PORTS_RANGE_FABRIC;
 175                         break;
 176                 default:
 177                         continue;
 178                 }
 179                 _zfcp_fc_incoming_rscn(fsf_req, range_mask, fcp_rscn_element);
 180         }
 181         schedule_work(&fsf_req->adapter->scan_work);
 182 }
 183
 184 static void zfcp_fc_incoming_wwpn(struct zfcp_fsf_req *req, u64 wwpn)
 185 {
 186         struct zfcp_adapter *adapter = req->adapter;
 187         struct zfcp_port *port;
 188         unsigned long flags;
 189
 190         read_lock_irqsave(&zfcp_data.config_lock, flags);
 191         list_for_each_entry(port, &adapter->port_list_head, list)
 192                 if (port->wwpn == wwpn)
 193                         break;
 194         read_unlock_irqrestore(&zfcp_data.config_lock, flags);
 195
 196         if (port && (port->wwpn == wwpn))
 197                 zfcp_erp_port_forced_reopen(port, 0, 83, req);
 198 }
 199
 200 static void zfcp_fc_incoming_plogi(struct zfcp_fsf_req *req)
 201 {
 202         struct fsf_status_read_buffer *status_buffer =
 203                 (struct fsf_status_read_buffer *)req->data;
 204         struct fsf_plogi *els_plogi =
 205                 (struct fsf_plogi *) status_buffer->payload.data;
 206
 207         zfcp_fc_incoming_wwpn(req, els_plogi->serv_param.wwpn);
 208 }
 209
 210 static void zfcp_fc_incoming_logo(struct zfcp_fsf_req *req)
 211 {
 212         struct fsf_status_read_buffer *status_buffer =
 213                 (struct fsf_status_read_buffer *)req->data;
 214         struct fcp_logo *els_logo =
 215                 (struct fcp_logo *) status_buffer->payload.data;
 216
 217         zfcp_fc_incoming_wwpn(req, els_logo->nport_wwpn);
 218 }
 219
 220 /**
 221  * zfcp_fc_incoming_els - handle incoming ELS
 222  * @fsf_req - request which contains incoming ELS
 223  */
 224 void zfcp_fc_incoming_els(struct zfcp_fsf_req *fsf_req)
 225 {
 226         struct fsf_status_read_buffer *status_buffer =
 227                 (struct fsf_status_read_buffer *) fsf_req->data;
 228         unsigned int els_type = status_buffer->payload.data[0];
 229
 230         zfcp_san_dbf_event_incoming_els(fsf_req);
 231         if (els_type == LS_PLOGI)
 232                 zfcp_fc_incoming_plogi(fsf_req);
 233         else if (els_type == LS_LOGO)
 234                 zfcp_fc_incoming_logo(fsf_req);
 235         else if (els_type == LS_RSCN)
 236                 zfcp_fc_incoming_rscn(fsf_req);
 237 }
 238
 239 static void zfcp_fc_ns_handler(unsigned long data)
 240 {
 241         struct zfcp_fc_ns_handler_data *compl_rec =
 242                         (struct zfcp_fc_ns_handler_data *) data;
 243
 244         if (compl_rec->handler)
 245                 compl_rec->handler(compl_rec->handler_data);
 246
 247         complete(&compl_rec->done);
 248 }
 249
 250 static void zfcp_fc_ns_gid_pn_eval(unsigned long data)
 251 {
 252         struct zfcp_gid_pn_data *gid_pn = (struct zfcp_gid_pn_data *) data;
 253         struct zfcp_send_ct *ct = &gid_pn->ct;
 254         struct ct_iu_gid_pn_req *ct_iu_req = sg_virt(ct->req);
 255         struct ct_iu_gid_pn_resp *ct_iu_resp = sg_virt(ct->resp);
 256         struct zfcp_port *port = gid_pn->port;
 257
 258         if (ct->status)
 259                 return;
 260         if (ct_iu_resp->header.cmd_rsp_code != ZFCP_CT_ACCEPT) {
 261                 atomic_set_mask(ZFCP_STATUS_PORT_INVALID_WWPN, &port->status);
 262                 return;
 263         }
 264         /* paranoia */
 265         if (ct_iu_req->wwpn != port->wwpn)
 266                 return;
 267         /* looks like a valid d_id */
 268         port->d_id = ct_iu_resp->d_id & ZFCP_DID_MASK;
 269         atomic_set_mask(ZFCP_STATUS_PORT_DID_DID, &port->status);
 270 }
 271
 272 int static zfcp_fc_ns_gid_pn_request(struct zfcp_erp_action *erp_action,
 273                                      struct zfcp_gid_pn_data *gid_pn)
 274 {
 275         struct zfcp_adapter *adapter = erp_action->adapter;
 276         struct zfcp_fc_ns_handler_data compl_rec;
 277         int ret;
 278
 279         /* setup parameters for send generic command */
 280         gid_pn->port = erp_action->port;
 281         gid_pn->ct.wka_port = &adapter->nsp;
 282         gid_pn->ct.handler = zfcp_fc_ns_handler;
 283         gid_pn->ct.handler_data = (unsigned long) &compl_rec;
 284         gid_pn->ct.timeout = ZFCP_NS_GID_PN_TIMEOUT;
 285         gid_pn->ct.req = &gid_pn->req;
 286         gid_pn->ct.resp = &gid_pn->resp;
 287         gid_pn->ct.req_count = 1;
 288         gid_pn->ct.resp_count = 1;
 289         sg_init_one(&gid_pn->req, &gid_pn->ct_iu_req,
 290                     sizeof(struct ct_iu_gid_pn_req));
 291         sg_init_one(&gid_pn->resp, &gid_pn->ct_iu_resp,
 292                     sizeof(struct ct_iu_gid_pn_resp));
 293
 294         /* setup nameserver request */
 295         gid_pn->ct_iu_req.header.revision = ZFCP_CT_REVISION;
 296         gid_pn->ct_iu_req.header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
 297         gid_pn->ct_iu_req.header.gs_subtype = ZFCP_CT_NAME_SERVER;
 298         gid_pn->ct_iu_req.header.options = ZFCP_CT_SYNCHRONOUS;
 299         gid_pn->ct_iu_req.header.cmd_rsp_code = ZFCP_CT_GID_PN;
 300         gid_pn->ct_iu_req.header.max_res_size = ZFCP_CT_MAX_SIZE;
 301         gid_pn->ct_iu_req.wwpn = erp_action->port->wwpn;
 302
 303         init_completion(&compl_rec.done);
 304         compl_rec.handler = zfcp_fc_ns_gid_pn_eval;
 305         compl_rec.handler_data = (unsigned long) gid_pn;
 306         ret = zfcp_fsf_send_ct(&gid_pn->ct, adapter->pool.fsf_req_erp,
 307                                erp_action);
 308         if (!ret)
 309                 wait_for_completion(&compl_rec.done);
 310         return ret;
 311 }
 312
 313 /**
 314  * zfcp_fc_ns_gid_pn_request - initiate GID_PN nameserver request
 315  * @erp_action: pointer to zfcp_erp_action where GID_PN request is needed
 316  * return: -ENOMEM on error, 0 otherwise
 317  */
 318 int zfcp_fc_ns_gid_pn(struct zfcp_erp_action *erp_action)
 319 {
 320         int ret;
 321         struct zfcp_gid_pn_data *gid_pn;
 322         struct zfcp_adapter *adapter = erp_action->adapter;
 323
 324         gid_pn = mempool_alloc(adapter->pool.data_gid_pn, GFP_ATOMIC);
 325         if (!gid_pn)
 326                 return -ENOMEM;
 327
 328         memset(gid_pn, 0, sizeof(*gid_pn));
 329
 330         ret = zfcp_wka_port_get(&adapter->nsp);
 331         if (ret)
 332                 goto out;
 333
 334         ret = zfcp_fc_ns_gid_pn_request(erp_action, gid_pn);
 335
 336         zfcp_wka_port_put(&adapter->nsp);
 337 out:
 338         mempool_free(gid_pn, adapter->pool.data_gid_pn);
 339         return ret;
 340 }
 341
 342 /**
 343  * zfcp_fc_plogi_evaluate - evaluate PLOGI playload
 344  * @port: zfcp_port structure
 345  * @plogi: plogi payload
 346  *
 347  * Evaluate PLOGI playload and copy important fields into zfcp_port structure
 348  */
 349 void zfcp_fc_plogi_evaluate(struct zfcp_port *port, struct fsf_plogi *plogi)
 350 {
 351         port->maxframe_size = plogi->serv_param.common_serv_param[7] |
 352                 ((plogi->serv_param.common_serv_param[6] & 0x0F) << 8);
 353         if (plogi->serv_param.class1_serv_param[0] & 0x80)
 354                 port->supported_classes |= FC_COS_CLASS1;
 355         if (plogi->serv_param.class2_serv_param[0] & 0x80)
 356                 port->supported_classes |= FC_COS_CLASS2;
 357         if (plogi->serv_param.class3_serv_param[0] & 0x80)
 358                 port->supported_classes |= FC_COS_CLASS3;
 359         if (plogi->serv_param.class4_serv_param[0] & 0x80)
 360                 port->supported_classes |= FC_COS_CLASS4;
 361 }
 362
 363 struct zfcp_els_adisc {
 364         struct zfcp_send_els els;
 365         struct scatterlist req;
 366         struct scatterlist resp;
 367         struct zfcp_ls_adisc ls_adisc;
 368         struct zfcp_ls_adisc ls_adisc_acc;
 369 };
 370
 371 static void zfcp_fc_adisc_handler(unsigned long data)
 372 {
 373         struct zfcp_els_adisc *adisc = (struct zfcp_els_adisc *) data;
 374         struct zfcp_port *port = adisc->els.port;
 375         struct zfcp_ls_adisc *ls_adisc = &adisc->ls_adisc_acc;
 376
 377         if (adisc->els.status) {
 378                 /* request rejected or timed out */
 379                 zfcp_erp_port_forced_reopen(port, 0, 63, NULL);
 380                 goto out;
 381         }
 382
 383         if (!port->wwnn)
 384                 port->wwnn = ls_adisc->wwnn;
 385
 386         if (port->wwpn != ls_adisc->wwpn)
 387                 zfcp_erp_port_reopen(port, 0, 64, NULL);
 388
 389  out:
 390         zfcp_port_put(port);
 391         kfree(adisc);
 392 }
 393
 394 static int zfcp_fc_adisc(struct zfcp_port *port)
 395 {
 396         struct zfcp_els_adisc *adisc;
 397         struct zfcp_adapter *adapter = port->adapter;
 398
 399         adisc = kzalloc(sizeof(struct zfcp_els_adisc), GFP_ATOMIC);
 400         if (!adisc)
 401                 return -ENOMEM;
 402
 403         adisc->els.req = &adisc->req;
 404         adisc->els.resp = &adisc->resp;
 405         sg_init_one(adisc->els.req, &adisc->ls_adisc,
 406                     sizeof(struct zfcp_ls_adisc));
 407         sg_init_one(adisc->els.resp, &adisc->ls_adisc_acc,
 408                     sizeof(struct zfcp_ls_adisc));
 409
 410         adisc->els.req_count = 1;
 411         adisc->els.resp_count = 1;
 412         adisc->els.adapter = adapter;
 413         adisc->els.port = port;
 414         adisc->els.d_id = port->d_id;
 415         adisc->els.handler = zfcp_fc_adisc_handler;
 416         adisc->els.handler_data = (unsigned long) adisc;
 417         adisc->els.ls_code = adisc->ls_adisc.code = ZFCP_LS_ADISC;
 418
 419         /* acc. to FC-FS, hard_nport_id in ADISC should not be set for ports
 420            without FC-AL-2 capability, so we don't set it */
 421         adisc->ls_adisc.wwpn = fc_host_port_name(adapter->scsi_host);
 422         adisc->ls_adisc.wwnn = fc_host_node_name(adapter->scsi_host);
 423         adisc->ls_adisc.nport_id = fc_host_port_id(adapter->scsi_host);
 424
 425         return zfcp_fsf_send_els(&adisc->els);
 426 }
 427
 428 /**
 429  * zfcp_test_link - lightweight link test procedure
 430  * @port: port to be tested
 431  *
 432  * Test status of a link to a remote port using the ELS command ADISC.
 433  * If there is a problem with the remote port, error recovery steps
 434  * will be triggered.
 435  */
 436 void zfcp_test_link(struct zfcp_port *port)
 437 {
 438         int retval;
 439
 440         zfcp_port_get(port);
 441         retval = zfcp_fc_adisc(port);
 442         if (retval == 0)
 443                 return;
 444
 445         /* send of ADISC was not possible */
 446         zfcp_port_put(port);
 447         if (retval != -EBUSY)
 448                 zfcp_erp_port_forced_reopen(port, 0, 65, NULL);
 449 }
 450
 451 static void zfcp_free_sg_env(struct zfcp_gpn_ft *gpn_ft)
 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, ZFCP_GPN_FT_BUFFERS);
 457
 458         kfree(gpn_ft);
 459 }
 460
 461 static struct zfcp_gpn_ft *zfcp_alloc_sg_env(void)
 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, ZFCP_GPN_FT_BUFFERS)) {
 479                 zfcp_free_sg_env(gpn_ft);
 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 {
 490         struct zfcp_send_ct *ct = &gpn_ft->ct;
 491         struct ct_iu_gpn_ft_req *req = sg_virt(&gpn_ft->sg_req);
 492         struct zfcp_fc_ns_handler_data compl_rec;
 493         int ret;
 494
 495         /* prepare CT IU for GPN_FT */
 496         req->header.revision = ZFCP_CT_REVISION;
 497         req->header.gs_type = ZFCP_CT_DIRECTORY_SERVICE;
 498         req->header.gs_subtype = ZFCP_CT_NAME_SERVER;
 499         req->header.options = ZFCP_CT_SYNCHRONOUS;
 500         req->header.cmd_rsp_code = ZFCP_CT_GPN_FT;
 501         req->header.max_res_size = (sizeof(struct gpn_ft_resp_acc) *
 502                                         (ZFCP_GPN_FT_MAX_ENTRIES - 1)) >> 2;
 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         ct->req_count = 1;
 516         ct->resp_count = ZFCP_GPN_FT_BUFFERS;
 517
 518         init_completion(&compl_rec.done);
 519         compl_rec.handler = NULL;
 520         ret = zfcp_fsf_send_ct(ct, NULL, NULL);
 521         if (!ret)
 522                 wait_for_completion(&compl_rec.done);
 523         return ret;
 524 }
 525
 526 static void zfcp_validate_port(struct zfcp_port *port)
 527 {
 528         struct zfcp_adapter *adapter = port->adapter;
 529
 530         atomic_clear_mask(ZFCP_STATUS_COMMON_NOESC, &port->status);
 531
 532         if ((port->supported_classes != 0) ||
 533             !list_empty(&port->unit_list_head)) {
 534                 zfcp_port_put(port);
 535                 return;
 536         }
 537         zfcp_erp_port_shutdown(port, 0, 151, NULL);
 538         zfcp_erp_wait(adapter);
 539         zfcp_port_put(port);
 540         zfcp_port_dequeue(port);
 541 }
 542
 543 static int zfcp_scan_eval_gpn_ft(struct zfcp_gpn_ft *gpn_ft)
 544 {
 545         struct zfcp_send_ct *ct = &gpn_ft->ct;
 546         struct scatterlist *sg = gpn_ft->sg_resp;
 547         struct ct_hdr *hdr = sg_virt(sg);
 548         struct gpn_ft_resp_acc *acc = sg_virt(sg);
 549         struct zfcp_adapter *adapter = ct->wka_port->adapter;
 550         struct zfcp_port *port, *tmp;
 551         u32 d_id;
 552         int ret = 0, x, last = 0;
 553
 554         if (ct->status)
 555                 return -EIO;
 556
 557         if (hdr->cmd_rsp_code != ZFCP_CT_ACCEPT) {
 558                 if (hdr->reason_code == ZFCP_CT_UNABLE_TO_PERFORM_CMD)
 559                         return -EAGAIN; /* might be a temporary condition */
 560                 return -EIO;
 561         }
 562
 563         if (hdr->max_res_size)
 564                 return -E2BIG;
 565
 566         down(&zfcp_data.config_sema);
 567
 568         /* first entry is the header */
 569         for (x = 1; x < ZFCP_GPN_FT_MAX_ENTRIES && !last; x++) {
 570                 if (x % (ZFCP_GPN_FT_ENTRIES + 1))
 571                         acc++;
 572                 else
 573                         acc = sg_virt(++sg);
 574
 575                 last = acc->control & 0x80;
 576                 d_id = acc->port_id[0] << 16 | acc->port_id[1] << 8 |
 577                        acc->port_id[2];
 578
 579                 /* don't attach ports with a well known address */
 580                 if ((d_id & ZFCP_DID_WKA) == ZFCP_DID_WKA)
 581                         continue;
 582                 /* skip the adapter's port and known remote ports */
 583                 if (acc->wwpn == fc_host_port_name(adapter->scsi_host))
 584                         continue;
 585                 port = zfcp_get_port_by_wwpn(adapter, acc->wwpn);
 586                 if (port) {
 587                         zfcp_port_get(port);
 588                         continue;
 589                 }
 590
 591                 port = zfcp_port_enqueue(adapter, acc->wwpn,
 592                                          ZFCP_STATUS_PORT_DID_DID |
 593                                          ZFCP_STATUS_COMMON_NOESC, d_id);
 594                 if (IS_ERR(port))
 595                         ret = PTR_ERR(port);
 596                 else
 597                         zfcp_erp_port_reopen(port, 0, 149, NULL);
 598         }
 599
 600         zfcp_erp_wait(adapter);
 601         list_for_each_entry_safe(port, tmp, &adapter->port_list_head, list)
 602                 zfcp_validate_port(port);
 603         up(&zfcp_data.config_sema);
 604         return ret;
 605 }
 606
 607 /**
 608  * zfcp_scan_ports - scan remote ports and attach new ports
 609  * @adapter: pointer to struct zfcp_adapter
 610  */
 611 int zfcp_scan_ports(struct zfcp_adapter *adapter)
 612 {
 613         int ret, i;
 614         struct zfcp_gpn_ft *gpn_ft;
 615
 616         if (fc_host_port_type(adapter->scsi_host) != FC_PORTTYPE_NPORT)
 617                 return 0;
 618
 619         ret = zfcp_wka_port_get(&adapter->nsp);
 620         if (ret)
 621                 return ret;
 622
 623         gpn_ft = zfcp_alloc_sg_env();
 624         if (!gpn_ft) {
 625                 ret = -ENOMEM;
 626                 goto out;
 627         }
 628
 629         for (i = 0; i < 3; i++) {
 630                 ret = zfcp_scan_issue_gpn_ft(gpn_ft, adapter);
 631                 if (!ret) {
 632                         ret = zfcp_scan_eval_gpn_ft(gpn_ft);
 633                         if (ret == -EAGAIN)
 634                                 ssleep(1);
 635                         else
 636                                 break;
 637                 }
 638         }
 639         zfcp_free_sg_env(gpn_ft);
 640 out:
 641         zfcp_wka_port_put(&adapter->nsp);
 642         return ret;
 643 }
 644
 645
 646 void _zfcp_scan_ports_later(struct work_struct *work)
 647 {
 648         zfcp_scan_ports(container_of(work, struct zfcp_adapter, scan_work));
 649 }