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