1 /* 2 * Copyright(c) 2007 - 2008 Intel Corporation. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms and conditions of the GNU General Public License, 6 * version 2, as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License along with 14 * this program; if not, write to the Free Software Foundation, Inc., 15 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 16 * 17 * Maintained at www.Open-FCoE.org 18 */ 19 20 /* 21 * Target Discovery 22 * 23 * This block discovers all FC-4 remote ports, including FCP initiators. It 24 * also handles RSCN events and re-discovery if necessary. 25 */ 26 27 /* 28 * DISC LOCKING 29 * 30 * The disc mutex is can be locked when acquiring rport locks, but may not 31 * be held when acquiring the lport lock. Refer to fc_lport.c for more 32 * details. 33 */ 34 35 #include <linux/timer.h> 36 #include <linux/err.h> 37 #include <asm/unaligned.h> 38 39 #include <scsi/fc/fc_gs.h> 40 41 #include <scsi/libfc.h> 42 43 #include "fc_libfc.h" 44 45 #define FC_DISC_RETRY_LIMIT 3 /* max retries */ 46 #define FC_DISC_RETRY_DELAY 500UL /* (msecs) delay */ 47 48 static void fc_disc_gpn_ft_req(struct fc_disc *); 49 static void fc_disc_gpn_ft_resp(struct fc_seq *, struct fc_frame *, void *); 50 static void fc_disc_done(struct fc_disc *, enum fc_disc_event); 51 static void fc_disc_timeout(struct work_struct *); 52 static int fc_disc_single(struct fc_lport *, struct fc_disc_port *); 53 static void fc_disc_restart(struct fc_disc *); 54 55 /** 56 * fc_disc_stop_rports() - delete all the remote ports associated with the lport 57 * @disc: The discovery job to stop rports on 58 * 59 * Locking Note: This function expects that the lport mutex is locked before 60 * calling it. 61 */ 62 void fc_disc_stop_rports(struct fc_disc *disc) 63 { 64 struct fc_lport *lport; 65 struct fc_rport_priv *rdata, *next; 66 67 lport = disc->lport; 68 69 mutex_lock(&disc->disc_mutex); 70 list_for_each_entry_safe(rdata, next, &disc->rports, peers) 71 lport->tt.rport_logoff(rdata); 72 mutex_unlock(&disc->disc_mutex); 73 } 74 75 /** 76 * fc_disc_recv_rscn_req() - Handle Registered State Change Notification (RSCN) 77 * @sp: Current sequence of the RSCN exchange 78 * @fp: RSCN Frame 79 * @lport: Fibre Channel host port instance 80 * 81 * Locking Note: This function expects that the disc_mutex is locked 82 * before it is called. 83 */ 84 static void fc_disc_recv_rscn_req(struct fc_seq *sp, struct fc_frame *fp, 85 struct fc_disc *disc) 86 { 87 struct fc_lport *lport; 88 struct fc_els_rscn *rp; 89 struct fc_els_rscn_page *pp; 90 struct fc_seq_els_data rjt_data; 91 unsigned int len; 92 int redisc = 0; 93 enum fc_els_rscn_ev_qual ev_qual; 94 enum fc_els_rscn_addr_fmt fmt; 95 LIST_HEAD(disc_ports); 96 struct fc_disc_port *dp, *next; 97 98 lport = disc->lport; 99 100 FC_DISC_DBG(disc, "Received an RSCN event\n"); 101 102 /* make sure the frame contains an RSCN message */ 103 rp = fc_frame_payload_get(fp, sizeof(*rp)); 104 if (!rp) 105 goto reject; 106 /* make sure the page length is as expected (4 bytes) */ 107 if (rp->rscn_page_len != sizeof(*pp)) 108 goto reject; 109 /* get the RSCN payload length */ 110 len = ntohs(rp->rscn_plen); 111 if (len < sizeof(*rp)) 112 goto reject; 113 /* make sure the frame contains the expected payload */ 114 rp = fc_frame_payload_get(fp, len); 115 if (!rp) 116 goto reject; 117 /* payload must be a multiple of the RSCN page size */ 118 len -= sizeof(*rp); 119 if (len % sizeof(*pp)) 120 goto reject; 121 122 for (pp = (void *)(rp + 1); len > 0; len -= sizeof(*pp), pp++) { 123 ev_qual = pp->rscn_page_flags >> ELS_RSCN_EV_QUAL_BIT; 124 ev_qual &= ELS_RSCN_EV_QUAL_MASK; 125 fmt = pp->rscn_page_flags >> ELS_RSCN_ADDR_FMT_BIT; 126 fmt &= ELS_RSCN_ADDR_FMT_MASK; 127 /* 128 * if we get an address format other than port 129 * (area, domain, fabric), then do a full discovery 130 */ 131 switch (fmt) { 132 case ELS_ADDR_FMT_PORT: 133 FC_DISC_DBG(disc, "Port address format for port " 134 "(%6x)\n", ntoh24(pp->rscn_fid)); 135 dp = kzalloc(sizeof(*dp), GFP_KERNEL); 136 if (!dp) { 137 redisc = 1; 138 break; 139 } 140 dp->lp = lport; 141 dp->port_id = ntoh24(pp->rscn_fid); 142 list_add_tail(&dp->peers, &disc_ports); 143 break; 144 case ELS_ADDR_FMT_AREA: 145 case ELS_ADDR_FMT_DOM: 146 case ELS_ADDR_FMT_FAB: 147 default: 148 FC_DISC_DBG(disc, "Address format is (%d)\n", fmt); 149 redisc = 1; 150 break; 151 } 152 } 153 lport->tt.seq_els_rsp_send(sp, ELS_LS_ACC, NULL); 154 155 /* 156 * If not doing a complete rediscovery, do GPN_ID on 157 * the individual ports mentioned in the list. 158 * If any of these get an error, do a full rediscovery. 159 * In any case, go through the list and free the entries. 160 */ 161 list_for_each_entry_safe(dp, next, &disc_ports, peers) { 162 list_del(&dp->peers); 163 if (!redisc) 164 redisc = fc_disc_single(lport, dp); 165 kfree(dp); 166 } 167 if (redisc) { 168 FC_DISC_DBG(disc, "RSCN received: rediscovering\n"); 169 fc_disc_restart(disc); 170 } else { 171 FC_DISC_DBG(disc, "RSCN received: not rediscovering. " 172 "redisc %d state %d in_prog %d\n", 173 redisc, lport->state, disc->pending); 174 } 175 fc_frame_free(fp); 176 return; 177 reject: 178 FC_DISC_DBG(disc, "Received a bad RSCN frame\n"); 179 rjt_data.fp = NULL; 180 rjt_data.reason = ELS_RJT_LOGIC; 181 rjt_data.explan = ELS_EXPL_NONE; 182 lport->tt.seq_els_rsp_send(sp, ELS_LS_RJT, &rjt_data); 183 fc_frame_free(fp); 184 } 185 186 /** 187 * fc_disc_recv_req() - Handle incoming requests 188 * @sp: Current sequence of the request exchange 189 * @fp: The frame 190 * @lport: The FC local port 191 * 192 * Locking Note: This function is called from the EM and will lock 193 * the disc_mutex before calling the handler for the 194 * request. 195 */ 196 static void fc_disc_recv_req(struct fc_seq *sp, struct fc_frame *fp, 197 struct fc_lport *lport) 198 { 199 u8 op; 200 struct fc_disc *disc = &lport->disc; 201 202 op = fc_frame_payload_op(fp); 203 switch (op) { 204 case ELS_RSCN: 205 mutex_lock(&disc->disc_mutex); 206 fc_disc_recv_rscn_req(sp, fp, disc); 207 mutex_unlock(&disc->disc_mutex); 208 break; 209 default: 210 FC_DISC_DBG(disc, "Received an unsupported request, " 211 "the opcode is (%x)\n", op); 212 break; 213 } 214 } 215 216 /** 217 * fc_disc_restart() - Restart discovery 218 * @lport: FC discovery context 219 * 220 * Locking Note: This function expects that the disc mutex 221 * is already locked. 222 */ 223 static void fc_disc_restart(struct fc_disc *disc) 224 { 225 if (!disc->disc_callback) 226 return; 227 228 FC_DISC_DBG(disc, "Restarting discovery\n"); 229 230 disc->requested = 1; 231 if (disc->pending) 232 return; 233 234 /* 235 * Advance disc_id. This is an arbitrary non-zero number that will 236 * match the value in the fc_rport_priv after discovery for all 237 * freshly-discovered remote ports. Avoid wrapping to zero. 238 */ 239 disc->disc_id = (disc->disc_id + 2) | 1; 240 disc->retry_count = 0; 241 fc_disc_gpn_ft_req(disc); 242 } 243 244 /** 245 * fc_disc_start() - Fibre Channel Target discovery 246 * @lport: FC local port 247 * @disc_callback: function to be called when discovery is complete 248 */ 249 static void fc_disc_start(void (*disc_callback)(struct fc_lport *, 250 enum fc_disc_event), 251 struct fc_lport *lport) 252 { 253 struct fc_disc *disc = &lport->disc; 254 255 /* 256 * At this point we may have a new disc job or an existing 257 * one. Either way, let's lock when we make changes to it 258 * and send the GPN_FT request. 259 */ 260 mutex_lock(&disc->disc_mutex); 261 disc->disc_callback = disc_callback; 262 fc_disc_restart(disc); 263 mutex_unlock(&disc->disc_mutex); 264 } 265 266 /** 267 * fc_disc_done() - Discovery has been completed 268 * @disc: FC discovery context 269 * @event: discovery completion status 270 * 271 * Locking Note: This function expects that the disc mutex is locked before 272 * it is called. The discovery callback is then made with the lock released, 273 * and the lock is re-taken before returning from this function 274 */ 275 static void fc_disc_done(struct fc_disc *disc, enum fc_disc_event event) 276 { 277 struct fc_lport *lport = disc->lport; 278 struct fc_rport_priv *rdata; 279 280 FC_DISC_DBG(disc, "Discovery complete\n"); 281 282 disc->pending = 0; 283 if (disc->requested) { 284 fc_disc_restart(disc); 285 return; 286 } 287 288 /* 289 * Go through all remote ports. If they were found in the latest 290 * discovery, reverify or log them in. Otherwise, log them out. 291 * Skip ports which were never discovered. These are the dNS port 292 * and ports which were created by PLOGI. 293 */ 294 list_for_each_entry(rdata, &disc->rports, peers) { 295 if (!rdata->disc_id) 296 continue; 297 if (rdata->disc_id == disc->disc_id) 298 lport->tt.rport_login(rdata); 299 else 300 lport->tt.rport_logoff(rdata); 301 } 302 303 mutex_unlock(&disc->disc_mutex); 304 disc->disc_callback(lport, event); 305 mutex_lock(&disc->disc_mutex); 306 } 307 308 /** 309 * fc_disc_error() - Handle error on dNS request 310 * @disc: FC discovery context 311 * @fp: The frame pointer 312 */ 313 static void fc_disc_error(struct fc_disc *disc, struct fc_frame *fp) 314 { 315 struct fc_lport *lport = disc->lport; 316 unsigned long delay = 0; 317 318 FC_DISC_DBG(disc, "Error %ld, retries %d/%d\n", 319 PTR_ERR(fp), disc->retry_count, 320 FC_DISC_RETRY_LIMIT); 321 322 if (!fp || PTR_ERR(fp) == -FC_EX_TIMEOUT) { 323 /* 324 * Memory allocation failure, or the exchange timed out, 325 * retry after delay. 326 */ 327 if (disc->retry_count < FC_DISC_RETRY_LIMIT) { 328 /* go ahead and retry */ 329 if (!fp) 330 delay = msecs_to_jiffies(FC_DISC_RETRY_DELAY); 331 else { 332 delay = msecs_to_jiffies(lport->e_d_tov); 333 334 /* timeout faster first time */ 335 if (!disc->retry_count) 336 delay /= 4; 337 } 338 disc->retry_count++; 339 schedule_delayed_work(&disc->disc_work, delay); 340 } else 341 fc_disc_done(disc, DISC_EV_FAILED); 342 } 343 } 344 345 /** 346 * fc_disc_gpn_ft_req() - Send Get Port Names by FC-4 type (GPN_FT) request 347 * @lport: FC discovery context 348 * 349 * Locking Note: This function expects that the disc_mutex is locked 350 * before it is called. 351 */ 352 static void fc_disc_gpn_ft_req(struct fc_disc *disc) 353 { 354 struct fc_frame *fp; 355 struct fc_lport *lport = disc->lport; 356 357 WARN_ON(!fc_lport_test_ready(lport)); 358 359 disc->pending = 1; 360 disc->requested = 0; 361 362 disc->buf_len = 0; 363 disc->seq_count = 0; 364 fp = fc_frame_alloc(lport, 365 sizeof(struct fc_ct_hdr) + 366 sizeof(struct fc_ns_gid_ft)); 367 if (!fp) 368 goto err; 369 370 if (lport->tt.elsct_send(lport, 0, fp, 371 FC_NS_GPN_FT, 372 fc_disc_gpn_ft_resp, 373 disc, lport->e_d_tov)) 374 return; 375 err: 376 fc_disc_error(disc, NULL); 377 } 378 379 /** 380 * fc_disc_gpn_ft_parse() - Parse the body of the dNS GPN_FT response. 381 * @lport: Fibre Channel host port instance 382 * @buf: GPN_FT response buffer 383 * @len: size of response buffer 384 * 385 * Goes through the list of IDs and names resulting from a request. 386 */ 387 static int fc_disc_gpn_ft_parse(struct fc_disc *disc, void *buf, size_t len) 388 { 389 struct fc_lport *lport; 390 struct fc_gpn_ft_resp *np; 391 char *bp; 392 size_t plen; 393 size_t tlen; 394 int error = 0; 395 struct fc_rport_identifiers ids; 396 struct fc_rport_priv *rdata; 397 398 lport = disc->lport; 399 disc->seq_count++; 400 401 /* 402 * Handle partial name record left over from previous call. 403 */ 404 bp = buf; 405 plen = len; 406 np = (struct fc_gpn_ft_resp *)bp; 407 tlen = disc->buf_len; 408 disc->buf_len = 0; 409 if (tlen) { 410 WARN_ON(tlen >= sizeof(*np)); 411 plen = sizeof(*np) - tlen; 412 WARN_ON(plen <= 0); 413 WARN_ON(plen >= sizeof(*np)); 414 if (plen > len) 415 plen = len; 416 np = &disc->partial_buf; 417 memcpy((char *)np + tlen, bp, plen); 418 419 /* 420 * Set bp so that the loop below will advance it to the 421 * first valid full name element. 422 */ 423 bp -= tlen; 424 len += tlen; 425 plen += tlen; 426 disc->buf_len = (unsigned char) plen; 427 if (plen == sizeof(*np)) 428 disc->buf_len = 0; 429 } 430 431 /* 432 * Handle full name records, including the one filled from above. 433 * Normally, np == bp and plen == len, but from the partial case above, 434 * bp, len describe the overall buffer, and np, plen describe the 435 * partial buffer, which if would usually be full now. 436 * After the first time through the loop, things return to "normal". 437 */ 438 while (plen >= sizeof(*np)) { 439 ids.port_id = ntoh24(np->fp_fid); 440 ids.port_name = ntohll(np->fp_wwpn); 441 442 if (ids.port_id != fc_host_port_id(lport->host) && 443 ids.port_name != lport->wwpn) { 444 rdata = lport->tt.rport_create(lport, ids.port_id); 445 if (rdata) { 446 rdata->ids.port_name = ids.port_name; 447 rdata->disc_id = disc->disc_id; 448 } else { 449 printk(KERN_WARNING "libfc: Failed to allocate " 450 "memory for the newly discovered port " 451 "(%6x)\n", ids.port_id); 452 error = -ENOMEM; 453 } 454 } 455 456 if (np->fp_flags & FC_NS_FID_LAST) { 457 fc_disc_done(disc, DISC_EV_SUCCESS); 458 len = 0; 459 break; 460 } 461 len -= sizeof(*np); 462 bp += sizeof(*np); 463 np = (struct fc_gpn_ft_resp *)bp; 464 plen = len; 465 } 466 467 /* 468 * Save any partial record at the end of the buffer for next time. 469 */ 470 if (error == 0 && len > 0 && len < sizeof(*np)) { 471 if (np != &disc->partial_buf) { 472 FC_DISC_DBG(disc, "Partial buffer remains " 473 "for discovery\n"); 474 memcpy(&disc->partial_buf, np, len); 475 } 476 disc->buf_len = (unsigned char) len; 477 } 478 return error; 479 } 480 481 /** 482 * fc_disc_timeout() - Retry handler for the disc component 483 * @work: Structure holding disc obj that needs retry discovery 484 * 485 * Handle retry of memory allocation for remote ports. 486 */ 487 static void fc_disc_timeout(struct work_struct *work) 488 { 489 struct fc_disc *disc = container_of(work, 490 struct fc_disc, 491 disc_work.work); 492 mutex_lock(&disc->disc_mutex); 493 fc_disc_gpn_ft_req(disc); 494 mutex_unlock(&disc->disc_mutex); 495 } 496 497 /** 498 * fc_disc_gpn_ft_resp() - Handle a response frame from Get Port Names (GPN_FT) 499 * @sp: Current sequence of GPN_FT exchange 500 * @fp: response frame 501 * @lp_arg: Fibre Channel host port instance 502 * 503 * Locking Note: This function is called without disc mutex held, and 504 * should do all its processing with the mutex held 505 */ 506 static void fc_disc_gpn_ft_resp(struct fc_seq *sp, struct fc_frame *fp, 507 void *disc_arg) 508 { 509 struct fc_disc *disc = disc_arg; 510 struct fc_ct_hdr *cp; 511 struct fc_frame_header *fh; 512 enum fc_disc_event event = DISC_EV_NONE; 513 unsigned int seq_cnt; 514 unsigned int len; 515 int error = 0; 516 517 mutex_lock(&disc->disc_mutex); 518 FC_DISC_DBG(disc, "Received a GPN_FT response\n"); 519 520 if (IS_ERR(fp)) { 521 fc_disc_error(disc, fp); 522 mutex_unlock(&disc->disc_mutex); 523 return; 524 } 525 526 WARN_ON(!fc_frame_is_linear(fp)); /* buffer must be contiguous */ 527 fh = fc_frame_header_get(fp); 528 len = fr_len(fp) - sizeof(*fh); 529 seq_cnt = ntohs(fh->fh_seq_cnt); 530 if (fr_sof(fp) == FC_SOF_I3 && seq_cnt == 0 && disc->seq_count == 0) { 531 cp = fc_frame_payload_get(fp, sizeof(*cp)); 532 if (!cp) { 533 FC_DISC_DBG(disc, "GPN_FT response too short, len %d\n", 534 fr_len(fp)); 535 event = DISC_EV_FAILED; 536 } else if (ntohs(cp->ct_cmd) == FC_FS_ACC) { 537 538 /* Accepted, parse the response. */ 539 len -= sizeof(*cp); 540 error = fc_disc_gpn_ft_parse(disc, cp + 1, len); 541 } else if (ntohs(cp->ct_cmd) == FC_FS_RJT) { 542 FC_DISC_DBG(disc, "GPN_FT rejected reason %x exp %x " 543 "(check zoning)\n", cp->ct_reason, 544 cp->ct_explan); 545 event = DISC_EV_FAILED; 546 if (cp->ct_reason == FC_FS_RJT_UNABL && 547 cp->ct_explan == FC_FS_EXP_FTNR) 548 event = DISC_EV_SUCCESS; 549 } else { 550 FC_DISC_DBG(disc, "GPN_FT unexpected response code " 551 "%x\n", ntohs(cp->ct_cmd)); 552 event = DISC_EV_FAILED; 553 } 554 } else if (fr_sof(fp) == FC_SOF_N3 && seq_cnt == disc->seq_count) { 555 error = fc_disc_gpn_ft_parse(disc, fh + 1, len); 556 } else { 557 FC_DISC_DBG(disc, "GPN_FT unexpected frame - out of sequence? " 558 "seq_cnt %x expected %x sof %x eof %x\n", 559 seq_cnt, disc->seq_count, fr_sof(fp), fr_eof(fp)); 560 event = DISC_EV_FAILED; 561 } 562 if (error) 563 fc_disc_error(disc, fp); 564 else if (event != DISC_EV_NONE) 565 fc_disc_done(disc, event); 566 fc_frame_free(fp); 567 mutex_unlock(&disc->disc_mutex); 568 } 569 570 /** 571 * fc_disc_gpn_id_resp() - Handle a response frame from Get Port Names (GPN_ID) 572 * @sp: exchange sequence 573 * @fp: response frame 574 * @rdata_arg: remote port private data 575 * 576 * Locking Note: This function is called without disc mutex held. 577 */ 578 static void fc_disc_gpn_id_resp(struct fc_seq *sp, struct fc_frame *fp, 579 void *rdata_arg) 580 { 581 struct fc_rport_priv *rdata = rdata_arg; 582 struct fc_rport_priv *new_rdata; 583 struct fc_lport *lport; 584 struct fc_disc *disc; 585 struct fc_ct_hdr *cp; 586 struct fc_ns_gid_pn *pn; 587 u64 port_name; 588 589 lport = rdata->local_port; 590 disc = &lport->disc; 591 592 mutex_lock(&disc->disc_mutex); 593 if (PTR_ERR(fp) == -FC_EX_CLOSED) 594 goto out; 595 if (IS_ERR(fp)) 596 goto redisc; 597 598 cp = fc_frame_payload_get(fp, sizeof(*cp)); 599 if (!cp) 600 goto redisc; 601 if (ntohs(cp->ct_cmd) == FC_FS_ACC) { 602 if (fr_len(fp) < sizeof(struct fc_frame_header) + 603 sizeof(*cp) + sizeof(*pn)) 604 goto redisc; 605 pn = (struct fc_ns_gid_pn *)(cp + 1); 606 port_name = get_unaligned_be64(&pn->fn_wwpn); 607 if (rdata->ids.port_name == -1) 608 rdata->ids.port_name = port_name; 609 else if (rdata->ids.port_name != port_name) { 610 FC_DISC_DBG(disc, "GPN_ID accepted. WWPN changed. " 611 "Port-id %x wwpn %llx\n", 612 rdata->ids.port_id, port_name); 613 lport->tt.rport_logoff(rdata); 614 615 new_rdata = lport->tt.rport_create(lport, 616 rdata->ids.port_id); 617 if (new_rdata) { 618 new_rdata->disc_id = disc->disc_id; 619 lport->tt.rport_login(new_rdata); 620 } 621 goto out; 622 } 623 rdata->disc_id = disc->disc_id; 624 lport->tt.rport_login(rdata); 625 } else if (ntohs(cp->ct_cmd) == FC_FS_RJT) { 626 FC_DISC_DBG(disc, "GPN_ID rejected reason %x exp %x\n", 627 cp->ct_reason, cp->ct_explan); 628 lport->tt.rport_logoff(rdata); 629 } else { 630 FC_DISC_DBG(disc, "GPN_ID unexpected response code %x\n", 631 ntohs(cp->ct_cmd)); 632 redisc: 633 fc_disc_restart(disc); 634 } 635 out: 636 mutex_unlock(&disc->disc_mutex); 637 kref_put(&rdata->kref, lport->tt.rport_destroy); 638 } 639 640 /** 641 * fc_disc_gpn_id_req() - Send Get Port Names by ID (GPN_ID) request 642 * @lport: local port 643 * @rdata: remote port private data 644 * 645 * Locking Note: This function expects that the disc_mutex is locked 646 * before it is called. 647 * On failure, an error code is returned. 648 */ 649 static int fc_disc_gpn_id_req(struct fc_lport *lport, 650 struct fc_rport_priv *rdata) 651 { 652 struct fc_frame *fp; 653 654 fp = fc_frame_alloc(lport, sizeof(struct fc_ct_hdr) + 655 sizeof(struct fc_ns_fid)); 656 if (!fp) 657 return -ENOMEM; 658 if (!lport->tt.elsct_send(lport, rdata->ids.port_id, fp, FC_NS_GPN_ID, 659 fc_disc_gpn_id_resp, rdata, lport->e_d_tov)) 660 return -ENOMEM; 661 kref_get(&rdata->kref); 662 return 0; 663 } 664 665 /** 666 * fc_disc_single() - Discover the directory information for a single target 667 * @lport: local port 668 * @dp: The port to rediscover 669 * 670 * Locking Note: This function expects that the disc_mutex is locked 671 * before it is called. 672 */ 673 static int fc_disc_single(struct fc_lport *lport, struct fc_disc_port *dp) 674 { 675 struct fc_rport_priv *rdata; 676 677 rdata = lport->tt.rport_create(lport, dp->port_id); 678 if (!rdata) 679 return -ENOMEM; 680 rdata->disc_id = 0; 681 return fc_disc_gpn_id_req(lport, rdata); 682 } 683 684 /** 685 * fc_disc_stop() - Stop discovery for a given lport 686 * @lport: The lport that discovery should stop for 687 */ 688 void fc_disc_stop(struct fc_lport *lport) 689 { 690 struct fc_disc *disc = &lport->disc; 691 692 if (disc) { 693 cancel_delayed_work_sync(&disc->disc_work); 694 fc_disc_stop_rports(disc); 695 } 696 } 697 698 /** 699 * fc_disc_stop_final() - Stop discovery for a given lport 700 * @lport: The lport that discovery should stop for 701 * 702 * This function will block until discovery has been 703 * completely stopped and all rports have been deleted. 704 */ 705 void fc_disc_stop_final(struct fc_lport *lport) 706 { 707 fc_disc_stop(lport); 708 lport->tt.rport_flush_queue(); 709 } 710 711 /** 712 * fc_disc_init() - Initialize the discovery block 713 * @lport: FC local port 714 */ 715 int fc_disc_init(struct fc_lport *lport) 716 { 717 struct fc_disc *disc; 718 719 if (!lport->tt.disc_start) 720 lport->tt.disc_start = fc_disc_start; 721 722 if (!lport->tt.disc_stop) 723 lport->tt.disc_stop = fc_disc_stop; 724 725 if (!lport->tt.disc_stop_final) 726 lport->tt.disc_stop_final = fc_disc_stop_final; 727 728 if (!lport->tt.disc_recv_req) 729 lport->tt.disc_recv_req = fc_disc_recv_req; 730 731 disc = &lport->disc; 732 INIT_DELAYED_WORK(&disc->disc_work, fc_disc_timeout); 733 mutex_init(&disc->disc_mutex); 734 INIT_LIST_HEAD(&disc->rports); 735 736 disc->lport = lport; 737 738 return 0; 739 } 740 EXPORT_SYMBOL(fc_disc_init); 741