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/slab.h> 37#include <linux/err.h> 38#include <linux/export.h> 39#include <asm/unaligned.h> 40 41#include <scsi/fc/fc_gs.h> 42 43#include <scsi/libfc.h> 44 45#include "fc_libfc.h" 46 47#define FC_DISC_RETRY_LIMIT 3 /* max retries */ 48#define FC_DISC_RETRY_DELAY 500UL /* (msecs) delay */ 49 50static void fc_disc_gpn_ft_req(struct fc_disc *); 51static void fc_disc_gpn_ft_resp(struct fc_seq *, struct fc_frame *, void *); 52static void fc_disc_done(struct fc_disc *, enum fc_disc_event); 53static void fc_disc_timeout(struct work_struct *); 54static int fc_disc_single(struct fc_lport *, struct fc_disc_port *); 55static void fc_disc_restart(struct fc_disc *); 56 57/** 58 * fc_disc_stop_rports() - Delete all the remote ports associated with the lport 59 * @disc: The discovery job to stop remote ports on 60 * 61 * Locking Note: This function expects that the lport mutex is locked before 62 * calling it. 63 */ 64static void fc_disc_stop_rports(struct fc_disc *disc) 65{ 66 struct fc_lport *lport; 67 struct fc_rport_priv *rdata; 68 69 lport = fc_disc_lport(disc); 70 71 mutex_lock(&disc->disc_mutex); 72 list_for_each_entry_rcu(rdata, &disc->rports, peers) 73 lport->tt.rport_logoff(rdata); 74 mutex_unlock(&disc->disc_mutex); 75} 76 77/** 78 * fc_disc_recv_rscn_req() - Handle Registered State Change Notification (RSCN) 79 * @disc: The discovery object to which the RSCN applies 80 * @fp: The RSCN frame 81 * 82 * Locking Note: This function expects that the disc_mutex is locked 83 * before it is called. 84 */ 85static void fc_disc_recv_rscn_req(struct fc_disc *disc, struct fc_frame *fp) 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 = fc_disc_lport(disc); 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 "(%6.6x)\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(fp, 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; 177reject: 178 FC_DISC_DBG(disc, "Received a bad RSCN frame\n"); 179 rjt_data.reason = ELS_RJT_LOGIC; 180 rjt_data.explan = ELS_EXPL_NONE; 181 lport->tt.seq_els_rsp_send(fp, ELS_LS_RJT, &rjt_data); 182 fc_frame_free(fp); 183} 184 185/** 186 * fc_disc_recv_req() - Handle incoming requests 187 * @lport: The local port receiving the request 188 * @fp: The request frame 189 * 190 * Locking Note: This function is called from the EM and will lock 191 * the disc_mutex before calling the handler for the 192 * request. 193 */ 194static void fc_disc_recv_req(struct fc_lport *lport, struct fc_frame *fp) 195{ 196 u8 op; 197 struct fc_disc *disc = &lport->disc; 198 199 op = fc_frame_payload_op(fp); 200 switch (op) { 201 case ELS_RSCN: 202 mutex_lock(&disc->disc_mutex); 203 fc_disc_recv_rscn_req(disc, fp); 204 mutex_unlock(&disc->disc_mutex); 205 break; 206 default: 207 FC_DISC_DBG(disc, "Received an unsupported request, " 208 "the opcode is (%x)\n", op); 209 fc_frame_free(fp); 210 break; 211 } 212} 213 214/** 215 * fc_disc_restart() - Restart discovery 216 * @disc: The discovery object to be restarted 217 * 218 * Locking Note: This function expects that the disc mutex 219 * is already locked. 220 */ 221static void fc_disc_restart(struct fc_disc *disc) 222{ 223 if (!disc->disc_callback) 224 return; 225 226 FC_DISC_DBG(disc, "Restarting discovery\n"); 227 228 disc->requested = 1; 229 if (disc->pending) 230 return; 231 232 /* 233 * Advance disc_id. This is an arbitrary non-zero number that will 234 * match the value in the fc_rport_priv after discovery for all 235 * freshly-discovered remote ports. Avoid wrapping to zero. 236 */ 237 disc->disc_id = (disc->disc_id + 2) | 1; 238 disc->retry_count = 0; 239 fc_disc_gpn_ft_req(disc); 240} 241 242/** 243 * fc_disc_start() - Start discovery on a local port 244 * @lport: The local port to have discovery started on 245 * @disc_callback: Callback function to be called when discovery is complete 246 */ 247static void fc_disc_start(void (*disc_callback)(struct fc_lport *, 248 enum fc_disc_event), 249 struct fc_lport *lport) 250{ 251 struct fc_disc *disc = &lport->disc; 252 253 /* 254 * At this point we may have a new disc job or an existing 255 * one. Either way, let's lock when we make changes to it 256 * and send the GPN_FT request. 257 */ 258 mutex_lock(&disc->disc_mutex); 259 disc->disc_callback = disc_callback; 260 fc_disc_restart(disc); 261 mutex_unlock(&disc->disc_mutex); 262} 263 264/** 265 * fc_disc_done() - Discovery has been completed 266 * @disc: The discovery context 267 * @event: The discovery completion status 268 * 269 * Locking Note: This function expects that the disc mutex is locked before 270 * it is called. The discovery callback is then made with the lock released, 271 * and the lock is re-taken before returning from this function 272 */ 273static void fc_disc_done(struct fc_disc *disc, enum fc_disc_event event) 274{ 275 struct fc_lport *lport = fc_disc_lport(disc); 276 struct fc_rport_priv *rdata; 277 278 FC_DISC_DBG(disc, "Discovery complete\n"); 279 280 disc->pending = 0; 281 if (disc->requested) { 282 fc_disc_restart(disc); 283 return; 284 } 285 286 /* 287 * Go through all remote ports. If they were found in the latest 288 * discovery, reverify or log them in. Otherwise, log them out. 289 * Skip ports which were never discovered. These are the dNS port 290 * and ports which were created by PLOGI. 291 */ 292 list_for_each_entry_rcu(rdata, &disc->rports, peers) { 293 if (!rdata->disc_id) 294 continue; 295 if (rdata->disc_id == disc->disc_id) 296 lport->tt.rport_login(rdata); 297 else 298 lport->tt.rport_logoff(rdata); 299 } 300 301 mutex_unlock(&disc->disc_mutex); 302 disc->disc_callback(lport, event); 303 mutex_lock(&disc->disc_mutex); 304} 305 306/** 307 * fc_disc_error() - Handle error on dNS request 308 * @disc: The discovery context 309 * @fp: The error code encoded as a frame pointer 310 */ 311static void fc_disc_error(struct fc_disc *disc, struct fc_frame *fp) 312{ 313 struct fc_lport *lport = fc_disc_lport(disc); 314 unsigned long delay = 0; 315 316 FC_DISC_DBG(disc, "Error %ld, retries %d/%d\n", 317 PTR_ERR(fp), disc->retry_count, 318 FC_DISC_RETRY_LIMIT); 319 320 if (!fp || PTR_ERR(fp) == -FC_EX_TIMEOUT) { 321 /* 322 * Memory allocation failure, or the exchange timed out, 323 * retry after delay. 324 */ 325 if (disc->retry_count < FC_DISC_RETRY_LIMIT) { 326 /* go ahead and retry */ 327 if (!fp) 328 delay = msecs_to_jiffies(FC_DISC_RETRY_DELAY); 329 else { 330 delay = msecs_to_jiffies(lport->e_d_tov); 331 332 /* timeout faster first time */ 333 if (!disc->retry_count) 334 delay /= 4; 335 } 336 disc->retry_count++; 337 schedule_delayed_work(&disc->disc_work, delay); 338 } else 339 fc_disc_done(disc, DISC_EV_FAILED); 340 } else if (PTR_ERR(fp) == -FC_EX_CLOSED) { 341 /* 342 * if discovery fails due to lport reset, clear 343 * pending flag so that subsequent discovery can 344 * continue 345 */ 346 disc->pending = 0; 347 } 348} 349 350/** 351 * fc_disc_gpn_ft_req() - Send Get Port Names by FC-4 type (GPN_FT) request 352 * @lport: The discovery context 353 * 354 * Locking Note: This function expects that the disc_mutex is locked 355 * before it is called. 356 */ 357static void fc_disc_gpn_ft_req(struct fc_disc *disc) 358{ 359 struct fc_frame *fp; 360 struct fc_lport *lport = fc_disc_lport(disc); 361 362 WARN_ON(!fc_lport_test_ready(lport)); 363 364 disc->pending = 1; 365 disc->requested = 0; 366 367 disc->buf_len = 0; 368 disc->seq_count = 0; 369 fp = fc_frame_alloc(lport, 370 sizeof(struct fc_ct_hdr) + 371 sizeof(struct fc_ns_gid_ft)); 372 if (!fp) 373 goto err; 374 375 if (lport->tt.elsct_send(lport, 0, fp, 376 FC_NS_GPN_FT, 377 fc_disc_gpn_ft_resp, 378 disc, 3 * lport->r_a_tov)) 379 return; 380err: 381 fc_disc_error(disc, NULL); 382} 383 384/** 385 * fc_disc_gpn_ft_parse() - Parse the body of the dNS GPN_FT response. 386 * @lport: The local port the GPN_FT was received on 387 * @buf: The GPN_FT response buffer 388 * @len: The size of response buffer 389 * 390 * Goes through the list of IDs and names resulting from a request. 391 */ 392static int fc_disc_gpn_ft_parse(struct fc_disc *disc, void *buf, size_t len) 393{ 394 struct fc_lport *lport; 395 struct fc_gpn_ft_resp *np; 396 char *bp; 397 size_t plen; 398 size_t tlen; 399 int error = 0; 400 struct fc_rport_identifiers ids; 401 struct fc_rport_priv *rdata; 402 403 lport = fc_disc_lport(disc); 404 disc->seq_count++; 405 406 /* 407 * Handle partial name record left over from previous call. 408 */ 409 bp = buf; 410 plen = len; 411 np = (struct fc_gpn_ft_resp *)bp; 412 tlen = disc->buf_len; 413 disc->buf_len = 0; 414 if (tlen) { 415 WARN_ON(tlen >= sizeof(*np)); 416 plen = sizeof(*np) - tlen; 417 WARN_ON(plen <= 0); 418 WARN_ON(plen >= sizeof(*np)); 419 if (plen > len) 420 plen = len; 421 np = &disc->partial_buf; 422 memcpy((char *)np + tlen, bp, plen); 423 424 /* 425 * Set bp so that the loop below will advance it to the 426 * first valid full name element. 427 */ 428 bp -= tlen; 429 len += tlen; 430 plen += tlen; 431 disc->buf_len = (unsigned char) plen; 432 if (plen == sizeof(*np)) 433 disc->buf_len = 0; 434 } 435 436 /* 437 * Handle full name records, including the one filled from above. 438 * Normally, np == bp and plen == len, but from the partial case above, 439 * bp, len describe the overall buffer, and np, plen describe the 440 * partial buffer, which if would usually be full now. 441 * After the first time through the loop, things return to "normal". 442 */ 443 while (plen >= sizeof(*np)) { 444 ids.port_id = ntoh24(np->fp_fid); 445 ids.port_name = ntohll(np->fp_wwpn); 446 447 if (ids.port_id != lport->port_id && 448 ids.port_name != lport->wwpn) { 449 rdata = lport->tt.rport_create(lport, ids.port_id); 450 if (rdata) { 451 rdata->ids.port_name = ids.port_name; 452 rdata->disc_id = disc->disc_id; 453 } else { 454 printk(KERN_WARNING "libfc: Failed to allocate " 455 "memory for the newly discovered port " 456 "(%6.6x)\n", ids.port_id); 457 error = -ENOMEM; 458 } 459 } 460 461 if (np->fp_flags & FC_NS_FID_LAST) { 462 fc_disc_done(disc, DISC_EV_SUCCESS); 463 len = 0; 464 break; 465 } 466 len -= sizeof(*np); 467 bp += sizeof(*np); 468 np = (struct fc_gpn_ft_resp *)bp; 469 plen = len; 470 } 471 472 /* 473 * Save any partial record at the end of the buffer for next time. 474 */ 475 if (error == 0 && len > 0 && len < sizeof(*np)) { 476 if (np != &disc->partial_buf) { 477 FC_DISC_DBG(disc, "Partial buffer remains " 478 "for discovery\n"); 479 memcpy(&disc->partial_buf, np, len); 480 } 481 disc->buf_len = (unsigned char) len; 482 } 483 return error; 484} 485 486/** 487 * fc_disc_timeout() - Handler for discovery timeouts 488 * @work: Structure holding discovery context that needs to retry discovery 489 */ 490static void fc_disc_timeout(struct work_struct *work) 491{ 492 struct fc_disc *disc = container_of(work, 493 struct fc_disc, 494 disc_work.work); 495 mutex_lock(&disc->disc_mutex); 496 fc_disc_gpn_ft_req(disc); 497 mutex_unlock(&disc->disc_mutex); 498} 499 500/** 501 * fc_disc_gpn_ft_resp() - Handle a response frame from Get Port Names (GPN_FT) 502 * @sp: The sequence that the GPN_FT response was received on 503 * @fp: The GPN_FT response frame 504 * @lp_arg: The discovery context 505 * 506 * Locking Note: This function is called without disc mutex held, and 507 * should do all its processing with the mutex held 508 */ 509static void fc_disc_gpn_ft_resp(struct fc_seq *sp, struct fc_frame *fp, 510 void *disc_arg) 511{ 512 struct fc_disc *disc = disc_arg; 513 struct fc_ct_hdr *cp; 514 struct fc_frame_header *fh; 515 enum fc_disc_event event = DISC_EV_NONE; 516 unsigned int seq_cnt; 517 unsigned int len; 518 int error = 0; 519 520 mutex_lock(&disc->disc_mutex); 521 FC_DISC_DBG(disc, "Received a GPN_FT response\n"); 522 523 if (IS_ERR(fp)) { 524 fc_disc_error(disc, fp); 525 mutex_unlock(&disc->disc_mutex); 526 return; 527 } 528 529 WARN_ON(!fc_frame_is_linear(fp)); /* buffer must be contiguous */ 530 fh = fc_frame_header_get(fp); 531 len = fr_len(fp) - sizeof(*fh); 532 seq_cnt = ntohs(fh->fh_seq_cnt); 533 if (fr_sof(fp) == FC_SOF_I3 && seq_cnt == 0 && disc->seq_count == 0) { 534 cp = fc_frame_payload_get(fp, sizeof(*cp)); 535 if (!cp) { 536 FC_DISC_DBG(disc, "GPN_FT response too short, len %d\n", 537 fr_len(fp)); 538 event = DISC_EV_FAILED; 539 } else if (ntohs(cp->ct_cmd) == FC_FS_ACC) { 540 541 /* Accepted, parse the response. */ 542 len -= sizeof(*cp); 543 error = fc_disc_gpn_ft_parse(disc, cp + 1, len); 544 } else if (ntohs(cp->ct_cmd) == FC_FS_RJT) { 545 FC_DISC_DBG(disc, "GPN_FT rejected reason %x exp %x " 546 "(check zoning)\n", cp->ct_reason, 547 cp->ct_explan); 548 event = DISC_EV_FAILED; 549 if (cp->ct_reason == FC_FS_RJT_UNABL && 550 cp->ct_explan == FC_FS_EXP_FTNR) 551 event = DISC_EV_SUCCESS; 552 } else { 553 FC_DISC_DBG(disc, "GPN_FT unexpected response code " 554 "%x\n", ntohs(cp->ct_cmd)); 555 event = DISC_EV_FAILED; 556 } 557 } else if (fr_sof(fp) == FC_SOF_N3 && seq_cnt == disc->seq_count) { 558 error = fc_disc_gpn_ft_parse(disc, fh + 1, len); 559 } else { 560 FC_DISC_DBG(disc, "GPN_FT unexpected frame - out of sequence? " 561 "seq_cnt %x expected %x sof %x eof %x\n", 562 seq_cnt, disc->seq_count, fr_sof(fp), fr_eof(fp)); 563 event = DISC_EV_FAILED; 564 } 565 if (error) 566 fc_disc_error(disc, fp); 567 else if (event != DISC_EV_NONE) 568 fc_disc_done(disc, event); 569 fc_frame_free(fp); 570 mutex_unlock(&disc->disc_mutex); 571} 572 573/** 574 * fc_disc_gpn_id_resp() - Handle a response frame from Get Port Names (GPN_ID) 575 * @sp: The sequence the GPN_ID is on 576 * @fp: The response frame 577 * @rdata_arg: The remote port that sent the GPN_ID response 578 * 579 * Locking Note: This function is called without disc mutex held. 580 */ 581static void fc_disc_gpn_id_resp(struct fc_seq *sp, struct fc_frame *fp, 582 void *rdata_arg) 583{ 584 struct fc_rport_priv *rdata = rdata_arg; 585 struct fc_rport_priv *new_rdata; 586 struct fc_lport *lport; 587 struct fc_disc *disc; 588 struct fc_ct_hdr *cp; 589 struct fc_ns_gid_pn *pn; 590 u64 port_name; 591 592 lport = rdata->local_port; 593 disc = &lport->disc; 594 595 mutex_lock(&disc->disc_mutex); 596 if (PTR_ERR(fp) == -FC_EX_CLOSED) 597 goto out; 598 if (IS_ERR(fp)) 599 goto redisc; 600 601 cp = fc_frame_payload_get(fp, sizeof(*cp)); 602 if (!cp) 603 goto redisc; 604 if (ntohs(cp->ct_cmd) == FC_FS_ACC) { 605 if (fr_len(fp) < sizeof(struct fc_frame_header) + 606 sizeof(*cp) + sizeof(*pn)) 607 goto redisc; 608 pn = (struct fc_ns_gid_pn *)(cp + 1); 609 port_name = get_unaligned_be64(&pn->fn_wwpn); 610 if (rdata->ids.port_name == -1) 611 rdata->ids.port_name = port_name; 612 else if (rdata->ids.port_name != port_name) { 613 FC_DISC_DBG(disc, "GPN_ID accepted. WWPN changed. " 614 "Port-id %6.6x wwpn %16.16llx\n", 615 rdata->ids.port_id, port_name); 616 lport->tt.rport_logoff(rdata); 617 618 new_rdata = lport->tt.rport_create(lport, 619 rdata->ids.port_id); 620 if (new_rdata) { 621 new_rdata->disc_id = disc->disc_id; 622 lport->tt.rport_login(new_rdata); 623 } 624 goto out; 625 } 626 rdata->disc_id = disc->disc_id; 627 lport->tt.rport_login(rdata); 628 } else if (ntohs(cp->ct_cmd) == FC_FS_RJT) { 629 FC_DISC_DBG(disc, "GPN_ID rejected reason %x exp %x\n", 630 cp->ct_reason, cp->ct_explan); 631 lport->tt.rport_logoff(rdata); 632 } else { 633 FC_DISC_DBG(disc, "GPN_ID unexpected response code %x\n", 634 ntohs(cp->ct_cmd)); 635redisc: 636 fc_disc_restart(disc); 637 } 638out: 639 mutex_unlock(&disc->disc_mutex); 640 kref_put(&rdata->kref, lport->tt.rport_destroy); 641} 642 643/** 644 * fc_disc_gpn_id_req() - Send Get Port Names by ID (GPN_ID) request 645 * @lport: The local port to initiate discovery on 646 * @rdata: remote port private data 647 * 648 * Locking Note: This function expects that the disc_mutex is locked 649 * before it is called. 650 * On failure, an error code is returned. 651 */ 652static int fc_disc_gpn_id_req(struct fc_lport *lport, 653 struct fc_rport_priv *rdata) 654{ 655 struct fc_frame *fp; 656 657 fp = fc_frame_alloc(lport, sizeof(struct fc_ct_hdr) + 658 sizeof(struct fc_ns_fid)); 659 if (!fp) 660 return -ENOMEM; 661 if (!lport->tt.elsct_send(lport, rdata->ids.port_id, fp, FC_NS_GPN_ID, 662 fc_disc_gpn_id_resp, rdata, 663 3 * lport->r_a_tov)) 664 return -ENOMEM; 665 kref_get(&rdata->kref); 666 return 0; 667} 668 669/** 670 * fc_disc_single() - Discover the directory information for a single target 671 * @lport: The local port the remote port is associated with 672 * @dp: The port to rediscover 673 * 674 * Locking Note: This function expects that the disc_mutex is locked 675 * before it is called. 676 */ 677static int fc_disc_single(struct fc_lport *lport, struct fc_disc_port *dp) 678{ 679 struct fc_rport_priv *rdata; 680 681 rdata = lport->tt.rport_create(lport, dp->port_id); 682 if (!rdata) 683 return -ENOMEM; 684 rdata->disc_id = 0; 685 return fc_disc_gpn_id_req(lport, rdata); 686} 687 688/** 689 * fc_disc_stop() - Stop discovery for a given lport 690 * @lport: The local port that discovery should stop on 691 */ 692static void fc_disc_stop(struct fc_lport *lport) 693{ 694 struct fc_disc *disc = &lport->disc; 695 696 if (disc->pending) 697 cancel_delayed_work_sync(&disc->disc_work); 698 fc_disc_stop_rports(disc); 699} 700 701/** 702 * fc_disc_stop_final() - Stop discovery for a given lport 703 * @lport: The lport that discovery should stop on 704 * 705 * This function will block until discovery has been 706 * completely stopped and all rports have been deleted. 707 */ 708static void fc_disc_stop_final(struct fc_lport *lport) 709{ 710 fc_disc_stop(lport); 711 lport->tt.rport_flush_queue(); 712} 713 714/** 715 * fc_disc_config() - Configure the discovery layer for a local port 716 * @lport: The local port that needs the discovery layer to be configured 717 * @priv: Private data structre for users of the discovery layer 718 */ 719void fc_disc_config(struct fc_lport *lport, void *priv) 720{ 721 struct fc_disc *disc = &lport->disc; 722 723 if (!lport->tt.disc_start) 724 lport->tt.disc_start = fc_disc_start; 725 726 if (!lport->tt.disc_stop) 727 lport->tt.disc_stop = fc_disc_stop; 728 729 if (!lport->tt.disc_stop_final) 730 lport->tt.disc_stop_final = fc_disc_stop_final; 731 732 if (!lport->tt.disc_recv_req) 733 lport->tt.disc_recv_req = fc_disc_recv_req; 734 735 disc = &lport->disc; 736 737 disc->priv = priv; 738} 739EXPORT_SYMBOL(fc_disc_config); 740 741/** 742 * fc_disc_init() - Initialize the discovery layer for a local port 743 * @lport: The local port that needs the discovery layer to be initialized 744 */ 745void fc_disc_init(struct fc_lport *lport) 746{ 747 struct fc_disc *disc = &lport->disc; 748 749 INIT_DELAYED_WORK(&disc->disc_work, fc_disc_timeout); 750 mutex_init(&disc->disc_mutex); 751 INIT_LIST_HEAD(&disc->rports); 752} 753EXPORT_SYMBOL(fc_disc_init); 754