1/* 2 * Copyright(c) 2007 Intel Corporation. All rights reserved. 3 * Copyright(c) 2008 Red Hat, Inc. All rights reserved. 4 * Copyright(c) 2008 Mike Christie 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms and conditions of the GNU General Public License, 8 * version 2, as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 * You should have received a copy of the GNU General Public License along with 16 * this program; if not, write to the Free Software Foundation, Inc., 17 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Maintained at www.Open-FCoE.org 20 */ 21 22/* 23 * Fibre Channel exchange and sequence handling. 24 */ 25 26#include <linux/timer.h> 27#include <linux/slab.h> 28#include <linux/err.h> 29#include <linux/export.h> 30 31#include <scsi/fc/fc_fc2.h> 32 33#include <scsi/libfc.h> 34#include <scsi/fc_encode.h> 35 36#include "fc_libfc.h" 37 38u16 fc_cpu_mask; /* cpu mask for possible cpus */ 39EXPORT_SYMBOL(fc_cpu_mask); 40static u16 fc_cpu_order; /* 2's power to represent total possible cpus */ 41static struct kmem_cache *fc_em_cachep; /* cache for exchanges */ 42static struct workqueue_struct *fc_exch_workqueue; 43 44/* 45 * Structure and function definitions for managing Fibre Channel Exchanges 46 * and Sequences. 47 * 48 * The three primary structures used here are fc_exch_mgr, fc_exch, and fc_seq. 49 * 50 * fc_exch_mgr holds the exchange state for an N port 51 * 52 * fc_exch holds state for one exchange and links to its active sequence. 53 * 54 * fc_seq holds the state for an individual sequence. 55 */ 56 57/** 58 * struct fc_exch_pool - Per cpu exchange pool 59 * @next_index: Next possible free exchange index 60 * @total_exches: Total allocated exchanges 61 * @lock: Exch pool lock 62 * @ex_list: List of exchanges 63 * 64 * This structure manages per cpu exchanges in array of exchange pointers. 65 * This array is allocated followed by struct fc_exch_pool memory for 66 * assigned range of exchanges to per cpu pool. 67 */ 68struct fc_exch_pool { 69 spinlock_t lock; 70 struct list_head ex_list; 71 u16 next_index; 72 u16 total_exches; 73 74 /* two cache of free slot in exch array */ 75 u16 left; 76 u16 right; 77} ____cacheline_aligned_in_smp; 78 79/** 80 * struct fc_exch_mgr - The Exchange Manager (EM). 81 * @class: Default class for new sequences 82 * @kref: Reference counter 83 * @min_xid: Minimum exchange ID 84 * @max_xid: Maximum exchange ID 85 * @ep_pool: Reserved exchange pointers 86 * @pool_max_index: Max exch array index in exch pool 87 * @pool: Per cpu exch pool 88 * @stats: Statistics structure 89 * 90 * This structure is the center for creating exchanges and sequences. 91 * It manages the allocation of exchange IDs. 92 */ 93struct fc_exch_mgr { 94 struct fc_exch_pool __percpu *pool; 95 mempool_t *ep_pool; 96 enum fc_class class; 97 struct kref kref; 98 u16 min_xid; 99 u16 max_xid; 100 u16 pool_max_index; 101 102 /* 103 * currently exchange mgr stats are updated but not used. 104 * either stats can be expose via sysfs or remove them 105 * all together if not used XXX 106 */ 107 struct { 108 atomic_t no_free_exch; 109 atomic_t no_free_exch_xid; 110 atomic_t xid_not_found; 111 atomic_t xid_busy; 112 atomic_t seq_not_found; 113 atomic_t non_bls_resp; 114 } stats; 115}; 116 117/** 118 * struct fc_exch_mgr_anchor - primary structure for list of EMs 119 * @ema_list: Exchange Manager Anchor list 120 * @mp: Exchange Manager associated with this anchor 121 * @match: Routine to determine if this anchor's EM should be used 122 * 123 * When walking the list of anchors the match routine will be called 124 * for each anchor to determine if that EM should be used. The last 125 * anchor in the list will always match to handle any exchanges not 126 * handled by other EMs. The non-default EMs would be added to the 127 * anchor list by HW that provides FCoE offloads. 128 */ 129struct fc_exch_mgr_anchor { 130 struct list_head ema_list; 131 struct fc_exch_mgr *mp; 132 bool (*match)(struct fc_frame *); 133}; 134 135static void fc_exch_rrq(struct fc_exch *); 136static void fc_seq_ls_acc(struct fc_frame *); 137static void fc_seq_ls_rjt(struct fc_frame *, enum fc_els_rjt_reason, 138 enum fc_els_rjt_explan); 139static void fc_exch_els_rec(struct fc_frame *); 140static void fc_exch_els_rrq(struct fc_frame *); 141 142/* 143 * Internal implementation notes. 144 * 145 * The exchange manager is one by default in libfc but LLD may choose 146 * to have one per CPU. The sequence manager is one per exchange manager 147 * and currently never separated. 148 * 149 * Section 9.8 in FC-FS-2 specifies: "The SEQ_ID is a one-byte field 150 * assigned by the Sequence Initiator that shall be unique for a specific 151 * D_ID and S_ID pair while the Sequence is open." Note that it isn't 152 * qualified by exchange ID, which one might think it would be. 153 * In practice this limits the number of open sequences and exchanges to 256 154 * per session. For most targets we could treat this limit as per exchange. 155 * 156 * The exchange and its sequence are freed when the last sequence is received. 157 * It's possible for the remote port to leave an exchange open without 158 * sending any sequences. 159 * 160 * Notes on reference counts: 161 * 162 * Exchanges are reference counted and exchange gets freed when the reference 163 * count becomes zero. 164 * 165 * Timeouts: 166 * Sequences are timed out for E_D_TOV and R_A_TOV. 167 * 168 * Sequence event handling: 169 * 170 * The following events may occur on initiator sequences: 171 * 172 * Send. 173 * For now, the whole thing is sent. 174 * Receive ACK 175 * This applies only to class F. 176 * The sequence is marked complete. 177 * ULP completion. 178 * The upper layer calls fc_exch_done() when done 179 * with exchange and sequence tuple. 180 * RX-inferred completion. 181 * When we receive the next sequence on the same exchange, we can 182 * retire the previous sequence ID. (XXX not implemented). 183 * Timeout. 184 * R_A_TOV frees the sequence ID. If we're waiting for ACK, 185 * E_D_TOV causes abort and calls upper layer response handler 186 * with FC_EX_TIMEOUT error. 187 * Receive RJT 188 * XXX defer. 189 * Send ABTS 190 * On timeout. 191 * 192 * The following events may occur on recipient sequences: 193 * 194 * Receive 195 * Allocate sequence for first frame received. 196 * Hold during receive handler. 197 * Release when final frame received. 198 * Keep status of last N of these for the ELS RES command. XXX TBD. 199 * Receive ABTS 200 * Deallocate sequence 201 * Send RJT 202 * Deallocate 203 * 204 * For now, we neglect conditions where only part of a sequence was 205 * received or transmitted, or where out-of-order receipt is detected. 206 */ 207 208/* 209 * Locking notes: 210 * 211 * The EM code run in a per-CPU worker thread. 212 * 213 * To protect against concurrency between a worker thread code and timers, 214 * sequence allocation and deallocation must be locked. 215 * - exchange refcnt can be done atomicly without locks. 216 * - sequence allocation must be locked by exch lock. 217 * - If the EM pool lock and ex_lock must be taken at the same time, then the 218 * EM pool lock must be taken before the ex_lock. 219 */ 220 221/* 222 * opcode names for debugging. 223 */ 224static char *fc_exch_rctl_names[] = FC_RCTL_NAMES_INIT; 225 226/** 227 * fc_exch_name_lookup() - Lookup name by opcode 228 * @op: Opcode to be looked up 229 * @table: Opcode/name table 230 * @max_index: Index not to be exceeded 231 * 232 * This routine is used to determine a human-readable string identifying 233 * a R_CTL opcode. 234 */ 235static inline const char *fc_exch_name_lookup(unsigned int op, char **table, 236 unsigned int max_index) 237{ 238 const char *name = NULL; 239 240 if (op < max_index) 241 name = table[op]; 242 if (!name) 243 name = "unknown"; 244 return name; 245} 246 247/** 248 * fc_exch_rctl_name() - Wrapper routine for fc_exch_name_lookup() 249 * @op: The opcode to be looked up 250 */ 251static const char *fc_exch_rctl_name(unsigned int op) 252{ 253 return fc_exch_name_lookup(op, fc_exch_rctl_names, 254 ARRAY_SIZE(fc_exch_rctl_names)); 255} 256 257/** 258 * fc_exch_hold() - Increment an exchange's reference count 259 * @ep: Echange to be held 260 */ 261static inline void fc_exch_hold(struct fc_exch *ep) 262{ 263 atomic_inc(&ep->ex_refcnt); 264} 265 266/** 267 * fc_exch_setup_hdr() - Initialize a FC header by initializing some fields 268 * and determine SOF and EOF. 269 * @ep: The exchange to that will use the header 270 * @fp: The frame whose header is to be modified 271 * @f_ctl: F_CTL bits that will be used for the frame header 272 * 273 * The fields initialized by this routine are: fh_ox_id, fh_rx_id, 274 * fh_seq_id, fh_seq_cnt and the SOF and EOF. 275 */ 276static void fc_exch_setup_hdr(struct fc_exch *ep, struct fc_frame *fp, 277 u32 f_ctl) 278{ 279 struct fc_frame_header *fh = fc_frame_header_get(fp); 280 u16 fill; 281 282 fr_sof(fp) = ep->class; 283 if (ep->seq.cnt) 284 fr_sof(fp) = fc_sof_normal(ep->class); 285 286 if (f_ctl & FC_FC_END_SEQ) { 287 fr_eof(fp) = FC_EOF_T; 288 if (fc_sof_needs_ack(ep->class)) 289 fr_eof(fp) = FC_EOF_N; 290 /* 291 * From F_CTL. 292 * The number of fill bytes to make the length a 4-byte 293 * multiple is the low order 2-bits of the f_ctl. 294 * The fill itself will have been cleared by the frame 295 * allocation. 296 * After this, the length will be even, as expected by 297 * the transport. 298 */ 299 fill = fr_len(fp) & 3; 300 if (fill) { 301 fill = 4 - fill; 302 /* TODO, this may be a problem with fragmented skb */ 303 skb_put(fp_skb(fp), fill); 304 hton24(fh->fh_f_ctl, f_ctl | fill); 305 } 306 } else { 307 WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */ 308 fr_eof(fp) = FC_EOF_N; 309 } 310 311 /* 312 * Initialize remainig fh fields 313 * from fc_fill_fc_hdr 314 */ 315 fh->fh_ox_id = htons(ep->oxid); 316 fh->fh_rx_id = htons(ep->rxid); 317 fh->fh_seq_id = ep->seq.id; 318 fh->fh_seq_cnt = htons(ep->seq.cnt); 319} 320 321/** 322 * fc_exch_release() - Decrement an exchange's reference count 323 * @ep: Exchange to be released 324 * 325 * If the reference count reaches zero and the exchange is complete, 326 * it is freed. 327 */ 328static void fc_exch_release(struct fc_exch *ep) 329{ 330 struct fc_exch_mgr *mp; 331 332 if (atomic_dec_and_test(&ep->ex_refcnt)) { 333 mp = ep->em; 334 if (ep->destructor) 335 ep->destructor(&ep->seq, ep->arg); 336 WARN_ON(!(ep->esb_stat & ESB_ST_COMPLETE)); 337 mempool_free(ep, mp->ep_pool); 338 } 339} 340 341/** 342 * fc_exch_done_locked() - Complete an exchange with the exchange lock held 343 * @ep: The exchange that is complete 344 */ 345static int fc_exch_done_locked(struct fc_exch *ep) 346{ 347 int rc = 1; 348 349 /* 350 * We must check for completion in case there are two threads 351 * tyring to complete this. But the rrq code will reuse the 352 * ep, and in that case we only clear the resp and set it as 353 * complete, so it can be reused by the timer to send the rrq. 354 */ 355 ep->resp = NULL; 356 if (ep->state & FC_EX_DONE) 357 return rc; 358 ep->esb_stat |= ESB_ST_COMPLETE; 359 360 if (!(ep->esb_stat & ESB_ST_REC_QUAL)) { 361 ep->state |= FC_EX_DONE; 362 if (cancel_delayed_work(&ep->timeout_work)) 363 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */ 364 rc = 0; 365 } 366 return rc; 367} 368 369/** 370 * fc_exch_ptr_get() - Return an exchange from an exchange pool 371 * @pool: Exchange Pool to get an exchange from 372 * @index: Index of the exchange within the pool 373 * 374 * Use the index to get an exchange from within an exchange pool. exches 375 * will point to an array of exchange pointers. The index will select 376 * the exchange within the array. 377 */ 378static inline struct fc_exch *fc_exch_ptr_get(struct fc_exch_pool *pool, 379 u16 index) 380{ 381 struct fc_exch **exches = (struct fc_exch **)(pool + 1); 382 return exches[index]; 383} 384 385/** 386 * fc_exch_ptr_set() - Assign an exchange to a slot in an exchange pool 387 * @pool: The pool to assign the exchange to 388 * @index: The index in the pool where the exchange will be assigned 389 * @ep: The exchange to assign to the pool 390 */ 391static inline void fc_exch_ptr_set(struct fc_exch_pool *pool, u16 index, 392 struct fc_exch *ep) 393{ 394 ((struct fc_exch **)(pool + 1))[index] = ep; 395} 396 397/** 398 * fc_exch_delete() - Delete an exchange 399 * @ep: The exchange to be deleted 400 */ 401static void fc_exch_delete(struct fc_exch *ep) 402{ 403 struct fc_exch_pool *pool; 404 u16 index; 405 406 pool = ep->pool; 407 spin_lock_bh(&pool->lock); 408 WARN_ON(pool->total_exches <= 0); 409 pool->total_exches--; 410 411 /* update cache of free slot */ 412 index = (ep->xid - ep->em->min_xid) >> fc_cpu_order; 413 if (pool->left == FC_XID_UNKNOWN) 414 pool->left = index; 415 else if (pool->right == FC_XID_UNKNOWN) 416 pool->right = index; 417 else 418 pool->next_index = index; 419 420 fc_exch_ptr_set(pool, index, NULL); 421 list_del(&ep->ex_list); 422 spin_unlock_bh(&pool->lock); 423 fc_exch_release(ep); /* drop hold for exch in mp */ 424} 425 426/** 427 * fc_exch_timer_set_locked() - Start a timer for an exchange w/ the 428 * the exchange lock held 429 * @ep: The exchange whose timer will start 430 * @timer_msec: The timeout period 431 * 432 * Used for upper level protocols to time out the exchange. 433 * The timer is cancelled when it fires or when the exchange completes. 434 */ 435static inline void fc_exch_timer_set_locked(struct fc_exch *ep, 436 unsigned int timer_msec) 437{ 438 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) 439 return; 440 441 FC_EXCH_DBG(ep, "Exchange timer armed\n"); 442 443 if (queue_delayed_work(fc_exch_workqueue, &ep->timeout_work, 444 msecs_to_jiffies(timer_msec))) 445 fc_exch_hold(ep); /* hold for timer */ 446} 447 448/** 449 * fc_exch_timer_set() - Lock the exchange and set the timer 450 * @ep: The exchange whose timer will start 451 * @timer_msec: The timeout period 452 */ 453static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec) 454{ 455 spin_lock_bh(&ep->ex_lock); 456 fc_exch_timer_set_locked(ep, timer_msec); 457 spin_unlock_bh(&ep->ex_lock); 458} 459 460/** 461 * fc_seq_send() - Send a frame using existing sequence/exchange pair 462 * @lport: The local port that the exchange will be sent on 463 * @sp: The sequence to be sent 464 * @fp: The frame to be sent on the exchange 465 */ 466static int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp, 467 struct fc_frame *fp) 468{ 469 struct fc_exch *ep; 470 struct fc_frame_header *fh = fc_frame_header_get(fp); 471 int error; 472 u32 f_ctl; 473 u8 fh_type = fh->fh_type; 474 475 ep = fc_seq_exch(sp); 476 WARN_ON((ep->esb_stat & ESB_ST_SEQ_INIT) != ESB_ST_SEQ_INIT); 477 478 f_ctl = ntoh24(fh->fh_f_ctl); 479 fc_exch_setup_hdr(ep, fp, f_ctl); 480 fr_encaps(fp) = ep->encaps; 481 482 /* 483 * update sequence count if this frame is carrying 484 * multiple FC frames when sequence offload is enabled 485 * by LLD. 486 */ 487 if (fr_max_payload(fp)) 488 sp->cnt += DIV_ROUND_UP((fr_len(fp) - sizeof(*fh)), 489 fr_max_payload(fp)); 490 else 491 sp->cnt++; 492 493 /* 494 * Send the frame. 495 */ 496 error = lport->tt.frame_send(lport, fp); 497 498 if (fh_type == FC_TYPE_BLS) 499 return error; 500 501 /* 502 * Update the exchange and sequence flags, 503 * assuming all frames for the sequence have been sent. 504 * We can only be called to send once for each sequence. 505 */ 506 spin_lock_bh(&ep->ex_lock); 507 ep->f_ctl = f_ctl & ~FC_FC_FIRST_SEQ; /* not first seq */ 508 if (f_ctl & FC_FC_SEQ_INIT) 509 ep->esb_stat &= ~ESB_ST_SEQ_INIT; 510 spin_unlock_bh(&ep->ex_lock); 511 return error; 512} 513 514/** 515 * fc_seq_alloc() - Allocate a sequence for a given exchange 516 * @ep: The exchange to allocate a new sequence for 517 * @seq_id: The sequence ID to be used 518 * 519 * We don't support multiple originated sequences on the same exchange. 520 * By implication, any previously originated sequence on this exchange 521 * is complete, and we reallocate the same sequence. 522 */ 523static struct fc_seq *fc_seq_alloc(struct fc_exch *ep, u8 seq_id) 524{ 525 struct fc_seq *sp; 526 527 sp = &ep->seq; 528 sp->ssb_stat = 0; 529 sp->cnt = 0; 530 sp->id = seq_id; 531 return sp; 532} 533 534/** 535 * fc_seq_start_next_locked() - Allocate a new sequence on the same 536 * exchange as the supplied sequence 537 * @sp: The sequence/exchange to get a new sequence for 538 */ 539static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp) 540{ 541 struct fc_exch *ep = fc_seq_exch(sp); 542 543 sp = fc_seq_alloc(ep, ep->seq_id++); 544 FC_EXCH_DBG(ep, "f_ctl %6x seq %2x\n", 545 ep->f_ctl, sp->id); 546 return sp; 547} 548 549/** 550 * fc_seq_start_next() - Lock the exchange and get a new sequence 551 * for a given sequence/exchange pair 552 * @sp: The sequence/exchange to get a new exchange for 553 */ 554static struct fc_seq *fc_seq_start_next(struct fc_seq *sp) 555{ 556 struct fc_exch *ep = fc_seq_exch(sp); 557 558 spin_lock_bh(&ep->ex_lock); 559 sp = fc_seq_start_next_locked(sp); 560 spin_unlock_bh(&ep->ex_lock); 561 562 return sp; 563} 564 565/* 566 * Set the response handler for the exchange associated with a sequence. 567 */ 568static void fc_seq_set_resp(struct fc_seq *sp, 569 void (*resp)(struct fc_seq *, struct fc_frame *, 570 void *), 571 void *arg) 572{ 573 struct fc_exch *ep = fc_seq_exch(sp); 574 575 spin_lock_bh(&ep->ex_lock); 576 ep->resp = resp; 577 ep->arg = arg; 578 spin_unlock_bh(&ep->ex_lock); 579} 580 581/** 582 * fc_exch_abort_locked() - Abort an exchange 583 * @ep: The exchange to be aborted 584 * @timer_msec: The period of time to wait before aborting 585 * 586 * Locking notes: Called with exch lock held 587 * 588 * Return value: 0 on success else error code 589 */ 590static int fc_exch_abort_locked(struct fc_exch *ep, 591 unsigned int timer_msec) 592{ 593 struct fc_seq *sp; 594 struct fc_frame *fp; 595 int error; 596 597 if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL) || 598 ep->state & (FC_EX_DONE | FC_EX_RST_CLEANUP)) 599 return -ENXIO; 600 601 /* 602 * Send the abort on a new sequence if possible. 603 */ 604 sp = fc_seq_start_next_locked(&ep->seq); 605 if (!sp) 606 return -ENOMEM; 607 608 ep->esb_stat |= ESB_ST_SEQ_INIT | ESB_ST_ABNORMAL; 609 if (timer_msec) 610 fc_exch_timer_set_locked(ep, timer_msec); 611 612 /* 613 * If not logged into the fabric, don't send ABTS but leave 614 * sequence active until next timeout. 615 */ 616 if (!ep->sid) 617 return 0; 618 619 /* 620 * Send an abort for the sequence that timed out. 621 */ 622 fp = fc_frame_alloc(ep->lp, 0); 623 if (fp) { 624 fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid, 625 FC_TYPE_BLS, FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); 626 error = fc_seq_send(ep->lp, sp, fp); 627 } else 628 error = -ENOBUFS; 629 return error; 630} 631 632/** 633 * fc_seq_exch_abort() - Abort an exchange and sequence 634 * @req_sp: The sequence to be aborted 635 * @timer_msec: The period of time to wait before aborting 636 * 637 * Generally called because of a timeout or an abort from the upper layer. 638 * 639 * Return value: 0 on success else error code 640 */ 641static int fc_seq_exch_abort(const struct fc_seq *req_sp, 642 unsigned int timer_msec) 643{ 644 struct fc_exch *ep; 645 int error; 646 647 ep = fc_seq_exch(req_sp); 648 spin_lock_bh(&ep->ex_lock); 649 error = fc_exch_abort_locked(ep, timer_msec); 650 spin_unlock_bh(&ep->ex_lock); 651 return error; 652} 653 654/** 655 * fc_exch_timeout() - Handle exchange timer expiration 656 * @work: The work_struct identifying the exchange that timed out 657 */ 658static void fc_exch_timeout(struct work_struct *work) 659{ 660 struct fc_exch *ep = container_of(work, struct fc_exch, 661 timeout_work.work); 662 struct fc_seq *sp = &ep->seq; 663 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg); 664 void *arg; 665 u32 e_stat; 666 int rc = 1; 667 668 FC_EXCH_DBG(ep, "Exchange timed out\n"); 669 670 spin_lock_bh(&ep->ex_lock); 671 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) 672 goto unlock; 673 674 e_stat = ep->esb_stat; 675 if (e_stat & ESB_ST_COMPLETE) { 676 ep->esb_stat = e_stat & ~ESB_ST_REC_QUAL; 677 spin_unlock_bh(&ep->ex_lock); 678 if (e_stat & ESB_ST_REC_QUAL) 679 fc_exch_rrq(ep); 680 goto done; 681 } else { 682 resp = ep->resp; 683 arg = ep->arg; 684 ep->resp = NULL; 685 if (e_stat & ESB_ST_ABNORMAL) 686 rc = fc_exch_done_locked(ep); 687 spin_unlock_bh(&ep->ex_lock); 688 if (!rc) 689 fc_exch_delete(ep); 690 if (resp) 691 resp(sp, ERR_PTR(-FC_EX_TIMEOUT), arg); 692 fc_seq_exch_abort(sp, 2 * ep->r_a_tov); 693 goto done; 694 } 695unlock: 696 spin_unlock_bh(&ep->ex_lock); 697done: 698 /* 699 * This release matches the hold taken when the timer was set. 700 */ 701 fc_exch_release(ep); 702} 703 704/** 705 * fc_exch_em_alloc() - Allocate an exchange from a specified EM. 706 * @lport: The local port that the exchange is for 707 * @mp: The exchange manager that will allocate the exchange 708 * 709 * Returns pointer to allocated fc_exch with exch lock held. 710 */ 711static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport, 712 struct fc_exch_mgr *mp) 713{ 714 struct fc_exch *ep; 715 unsigned int cpu; 716 u16 index; 717 struct fc_exch_pool *pool; 718 719 /* allocate memory for exchange */ 720 ep = mempool_alloc(mp->ep_pool, GFP_ATOMIC); 721 if (!ep) { 722 atomic_inc(&mp->stats.no_free_exch); 723 goto out; 724 } 725 memset(ep, 0, sizeof(*ep)); 726 727 cpu = get_cpu(); 728 pool = per_cpu_ptr(mp->pool, cpu); 729 spin_lock_bh(&pool->lock); 730 put_cpu(); 731 732 /* peek cache of free slot */ 733 if (pool->left != FC_XID_UNKNOWN) { 734 index = pool->left; 735 pool->left = FC_XID_UNKNOWN; 736 goto hit; 737 } 738 if (pool->right != FC_XID_UNKNOWN) { 739 index = pool->right; 740 pool->right = FC_XID_UNKNOWN; 741 goto hit; 742 } 743 744 index = pool->next_index; 745 /* allocate new exch from pool */ 746 while (fc_exch_ptr_get(pool, index)) { 747 index = index == mp->pool_max_index ? 0 : index + 1; 748 if (index == pool->next_index) 749 goto err; 750 } 751 pool->next_index = index == mp->pool_max_index ? 0 : index + 1; 752hit: 753 fc_exch_hold(ep); /* hold for exch in mp */ 754 spin_lock_init(&ep->ex_lock); 755 /* 756 * Hold exch lock for caller to prevent fc_exch_reset() 757 * from releasing exch while fc_exch_alloc() caller is 758 * still working on exch. 759 */ 760 spin_lock_bh(&ep->ex_lock); 761 762 fc_exch_ptr_set(pool, index, ep); 763 list_add_tail(&ep->ex_list, &pool->ex_list); 764 fc_seq_alloc(ep, ep->seq_id++); 765 pool->total_exches++; 766 spin_unlock_bh(&pool->lock); 767 768 /* 769 * update exchange 770 */ 771 ep->oxid = ep->xid = (index << fc_cpu_order | cpu) + mp->min_xid; 772 ep->em = mp; 773 ep->pool = pool; 774 ep->lp = lport; 775 ep->f_ctl = FC_FC_FIRST_SEQ; /* next seq is first seq */ 776 ep->rxid = FC_XID_UNKNOWN; 777 ep->class = mp->class; 778 INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout); 779out: 780 return ep; 781err: 782 spin_unlock_bh(&pool->lock); 783 atomic_inc(&mp->stats.no_free_exch_xid); 784 mempool_free(ep, mp->ep_pool); 785 return NULL; 786} 787 788/** 789 * fc_exch_alloc() - Allocate an exchange from an EM on a 790 * local port's list of EMs. 791 * @lport: The local port that will own the exchange 792 * @fp: The FC frame that the exchange will be for 793 * 794 * This function walks the list of exchange manager(EM) 795 * anchors to select an EM for a new exchange allocation. The 796 * EM is selected when a NULL match function pointer is encountered 797 * or when a call to a match function returns true. 798 */ 799static inline struct fc_exch *fc_exch_alloc(struct fc_lport *lport, 800 struct fc_frame *fp) 801{ 802 struct fc_exch_mgr_anchor *ema; 803 804 list_for_each_entry(ema, &lport->ema_list, ema_list) 805 if (!ema->match || ema->match(fp)) 806 return fc_exch_em_alloc(lport, ema->mp); 807 return NULL; 808} 809 810/** 811 * fc_exch_find() - Lookup and hold an exchange 812 * @mp: The exchange manager to lookup the exchange from 813 * @xid: The XID of the exchange to look up 814 */ 815static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid) 816{ 817 struct fc_exch_pool *pool; 818 struct fc_exch *ep = NULL; 819 820 if ((xid >= mp->min_xid) && (xid <= mp->max_xid)) { 821 pool = per_cpu_ptr(mp->pool, xid & fc_cpu_mask); 822 spin_lock_bh(&pool->lock); 823 ep = fc_exch_ptr_get(pool, (xid - mp->min_xid) >> fc_cpu_order); 824 if (ep && ep->xid == xid) 825 fc_exch_hold(ep); 826 spin_unlock_bh(&pool->lock); 827 } 828 return ep; 829} 830 831 832/** 833 * fc_exch_done() - Indicate that an exchange/sequence tuple is complete and 834 * the memory allocated for the related objects may be freed. 835 * @sp: The sequence that has completed 836 */ 837static void fc_exch_done(struct fc_seq *sp) 838{ 839 struct fc_exch *ep = fc_seq_exch(sp); 840 int rc; 841 842 spin_lock_bh(&ep->ex_lock); 843 rc = fc_exch_done_locked(ep); 844 spin_unlock_bh(&ep->ex_lock); 845 if (!rc) 846 fc_exch_delete(ep); 847} 848 849/** 850 * fc_exch_resp() - Allocate a new exchange for a response frame 851 * @lport: The local port that the exchange was for 852 * @mp: The exchange manager to allocate the exchange from 853 * @fp: The response frame 854 * 855 * Sets the responder ID in the frame header. 856 */ 857static struct fc_exch *fc_exch_resp(struct fc_lport *lport, 858 struct fc_exch_mgr *mp, 859 struct fc_frame *fp) 860{ 861 struct fc_exch *ep; 862 struct fc_frame_header *fh; 863 864 ep = fc_exch_alloc(lport, fp); 865 if (ep) { 866 ep->class = fc_frame_class(fp); 867 868 /* 869 * Set EX_CTX indicating we're responding on this exchange. 870 */ 871 ep->f_ctl |= FC_FC_EX_CTX; /* we're responding */ 872 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not new */ 873 fh = fc_frame_header_get(fp); 874 ep->sid = ntoh24(fh->fh_d_id); 875 ep->did = ntoh24(fh->fh_s_id); 876 ep->oid = ep->did; 877 878 /* 879 * Allocated exchange has placed the XID in the 880 * originator field. Move it to the responder field, 881 * and set the originator XID from the frame. 882 */ 883 ep->rxid = ep->xid; 884 ep->oxid = ntohs(fh->fh_ox_id); 885 ep->esb_stat |= ESB_ST_RESP | ESB_ST_SEQ_INIT; 886 if ((ntoh24(fh->fh_f_ctl) & FC_FC_SEQ_INIT) == 0) 887 ep->esb_stat &= ~ESB_ST_SEQ_INIT; 888 889 fc_exch_hold(ep); /* hold for caller */ 890 spin_unlock_bh(&ep->ex_lock); /* lock from fc_exch_alloc */ 891 } 892 return ep; 893} 894 895/** 896 * fc_seq_lookup_recip() - Find a sequence where the other end 897 * originated the sequence 898 * @lport: The local port that the frame was sent to 899 * @mp: The Exchange Manager to lookup the exchange from 900 * @fp: The frame associated with the sequence we're looking for 901 * 902 * If fc_pf_rjt_reason is FC_RJT_NONE then this function will have a hold 903 * on the ep that should be released by the caller. 904 */ 905static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport, 906 struct fc_exch_mgr *mp, 907 struct fc_frame *fp) 908{ 909 struct fc_frame_header *fh = fc_frame_header_get(fp); 910 struct fc_exch *ep = NULL; 911 struct fc_seq *sp = NULL; 912 enum fc_pf_rjt_reason reject = FC_RJT_NONE; 913 u32 f_ctl; 914 u16 xid; 915 916 f_ctl = ntoh24(fh->fh_f_ctl); 917 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != 0); 918 919 /* 920 * Lookup or create the exchange if we will be creating the sequence. 921 */ 922 if (f_ctl & FC_FC_EX_CTX) { 923 xid = ntohs(fh->fh_ox_id); /* we originated exch */ 924 ep = fc_exch_find(mp, xid); 925 if (!ep) { 926 atomic_inc(&mp->stats.xid_not_found); 927 reject = FC_RJT_OX_ID; 928 goto out; 929 } 930 if (ep->rxid == FC_XID_UNKNOWN) 931 ep->rxid = ntohs(fh->fh_rx_id); 932 else if (ep->rxid != ntohs(fh->fh_rx_id)) { 933 reject = FC_RJT_OX_ID; 934 goto rel; 935 } 936 } else { 937 xid = ntohs(fh->fh_rx_id); /* we are the responder */ 938 939 /* 940 * Special case for MDS issuing an ELS TEST with a 941 * bad rxid of 0. 942 * XXX take this out once we do the proper reject. 943 */ 944 if (xid == 0 && fh->fh_r_ctl == FC_RCTL_ELS_REQ && 945 fc_frame_payload_op(fp) == ELS_TEST) { 946 fh->fh_rx_id = htons(FC_XID_UNKNOWN); 947 xid = FC_XID_UNKNOWN; 948 } 949 950 /* 951 * new sequence - find the exchange 952 */ 953 ep = fc_exch_find(mp, xid); 954 if ((f_ctl & FC_FC_FIRST_SEQ) && fc_sof_is_init(fr_sof(fp))) { 955 if (ep) { 956 atomic_inc(&mp->stats.xid_busy); 957 reject = FC_RJT_RX_ID; 958 goto rel; 959 } 960 ep = fc_exch_resp(lport, mp, fp); 961 if (!ep) { 962 reject = FC_RJT_EXCH_EST; /* XXX */ 963 goto out; 964 } 965 xid = ep->xid; /* get our XID */ 966 } else if (!ep) { 967 atomic_inc(&mp->stats.xid_not_found); 968 reject = FC_RJT_RX_ID; /* XID not found */ 969 goto out; 970 } 971 } 972 973 /* 974 * At this point, we have the exchange held. 975 * Find or create the sequence. 976 */ 977 if (fc_sof_is_init(fr_sof(fp))) { 978 sp = &ep->seq; 979 sp->ssb_stat |= SSB_ST_RESP; 980 sp->id = fh->fh_seq_id; 981 } else { 982 sp = &ep->seq; 983 if (sp->id != fh->fh_seq_id) { 984 atomic_inc(&mp->stats.seq_not_found); 985 if (f_ctl & FC_FC_END_SEQ) { 986 /* 987 * Update sequence_id based on incoming last 988 * frame of sequence exchange. This is needed 989 * for FCoE target where DDP has been used 990 * on target where, stack is indicated only 991 * about last frame's (payload _header) header. 992 * Whereas "seq_id" which is part of 993 * frame_header is allocated by initiator 994 * which is totally different from "seq_id" 995 * allocated when XFER_RDY was sent by target. 996 * To avoid false -ve which results into not 997 * sending RSP, hence write request on other 998 * end never finishes. 999 */ 1000 spin_lock_bh(&ep->ex_lock); 1001 sp->ssb_stat |= SSB_ST_RESP; 1002 sp->id = fh->fh_seq_id; 1003 spin_unlock_bh(&ep->ex_lock); 1004 } else { 1005 /* sequence/exch should exist */ 1006 reject = FC_RJT_SEQ_ID; 1007 goto rel; 1008 } 1009 } 1010 } 1011 WARN_ON(ep != fc_seq_exch(sp)); 1012 1013 if (f_ctl & FC_FC_SEQ_INIT) 1014 ep->esb_stat |= ESB_ST_SEQ_INIT; 1015 1016 fr_seq(fp) = sp; 1017out: 1018 return reject; 1019rel: 1020 fc_exch_done(&ep->seq); 1021 fc_exch_release(ep); /* hold from fc_exch_find/fc_exch_resp */ 1022 return reject; 1023} 1024 1025/** 1026 * fc_seq_lookup_orig() - Find a sequence where this end 1027 * originated the sequence 1028 * @mp: The Exchange Manager to lookup the exchange from 1029 * @fp: The frame associated with the sequence we're looking for 1030 * 1031 * Does not hold the sequence for the caller. 1032 */ 1033static struct fc_seq *fc_seq_lookup_orig(struct fc_exch_mgr *mp, 1034 struct fc_frame *fp) 1035{ 1036 struct fc_frame_header *fh = fc_frame_header_get(fp); 1037 struct fc_exch *ep; 1038 struct fc_seq *sp = NULL; 1039 u32 f_ctl; 1040 u16 xid; 1041 1042 f_ctl = ntoh24(fh->fh_f_ctl); 1043 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != FC_FC_SEQ_CTX); 1044 xid = ntohs((f_ctl & FC_FC_EX_CTX) ? fh->fh_ox_id : fh->fh_rx_id); 1045 ep = fc_exch_find(mp, xid); 1046 if (!ep) 1047 return NULL; 1048 if (ep->seq.id == fh->fh_seq_id) { 1049 /* 1050 * Save the RX_ID if we didn't previously know it. 1051 */ 1052 sp = &ep->seq; 1053 if ((f_ctl & FC_FC_EX_CTX) != 0 && 1054 ep->rxid == FC_XID_UNKNOWN) { 1055 ep->rxid = ntohs(fh->fh_rx_id); 1056 } 1057 } 1058 fc_exch_release(ep); 1059 return sp; 1060} 1061 1062/** 1063 * fc_exch_set_addr() - Set the source and destination IDs for an exchange 1064 * @ep: The exchange to set the addresses for 1065 * @orig_id: The originator's ID 1066 * @resp_id: The responder's ID 1067 * 1068 * Note this must be done before the first sequence of the exchange is sent. 1069 */ 1070static void fc_exch_set_addr(struct fc_exch *ep, 1071 u32 orig_id, u32 resp_id) 1072{ 1073 ep->oid = orig_id; 1074 if (ep->esb_stat & ESB_ST_RESP) { 1075 ep->sid = resp_id; 1076 ep->did = orig_id; 1077 } else { 1078 ep->sid = orig_id; 1079 ep->did = resp_id; 1080 } 1081} 1082 1083/** 1084 * fc_seq_els_rsp_send() - Send an ELS response using information from 1085 * the existing sequence/exchange. 1086 * @fp: The received frame 1087 * @els_cmd: The ELS command to be sent 1088 * @els_data: The ELS data to be sent 1089 * 1090 * The received frame is not freed. 1091 */ 1092static void fc_seq_els_rsp_send(struct fc_frame *fp, enum fc_els_cmd els_cmd, 1093 struct fc_seq_els_data *els_data) 1094{ 1095 switch (els_cmd) { 1096 case ELS_LS_RJT: 1097 fc_seq_ls_rjt(fp, els_data->reason, els_data->explan); 1098 break; 1099 case ELS_LS_ACC: 1100 fc_seq_ls_acc(fp); 1101 break; 1102 case ELS_RRQ: 1103 fc_exch_els_rrq(fp); 1104 break; 1105 case ELS_REC: 1106 fc_exch_els_rec(fp); 1107 break; 1108 default: 1109 FC_LPORT_DBG(fr_dev(fp), "Invalid ELS CMD:%x\n", els_cmd); 1110 } 1111} 1112 1113/** 1114 * fc_seq_send_last() - Send a sequence that is the last in the exchange 1115 * @sp: The sequence that is to be sent 1116 * @fp: The frame that will be sent on the sequence 1117 * @rctl: The R_CTL information to be sent 1118 * @fh_type: The frame header type 1119 */ 1120static void fc_seq_send_last(struct fc_seq *sp, struct fc_frame *fp, 1121 enum fc_rctl rctl, enum fc_fh_type fh_type) 1122{ 1123 u32 f_ctl; 1124 struct fc_exch *ep = fc_seq_exch(sp); 1125 1126 f_ctl = FC_FC_LAST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT; 1127 f_ctl |= ep->f_ctl; 1128 fc_fill_fc_hdr(fp, rctl, ep->did, ep->sid, fh_type, f_ctl, 0); 1129 fc_seq_send(ep->lp, sp, fp); 1130} 1131 1132/** 1133 * fc_seq_send_ack() - Send an acknowledgement that we've received a frame 1134 * @sp: The sequence to send the ACK on 1135 * @rx_fp: The received frame that is being acknoledged 1136 * 1137 * Send ACK_1 (or equiv.) indicating we received something. 1138 */ 1139static void fc_seq_send_ack(struct fc_seq *sp, const struct fc_frame *rx_fp) 1140{ 1141 struct fc_frame *fp; 1142 struct fc_frame_header *rx_fh; 1143 struct fc_frame_header *fh; 1144 struct fc_exch *ep = fc_seq_exch(sp); 1145 struct fc_lport *lport = ep->lp; 1146 unsigned int f_ctl; 1147 1148 /* 1149 * Don't send ACKs for class 3. 1150 */ 1151 if (fc_sof_needs_ack(fr_sof(rx_fp))) { 1152 fp = fc_frame_alloc(lport, 0); 1153 if (!fp) 1154 return; 1155 1156 fh = fc_frame_header_get(fp); 1157 fh->fh_r_ctl = FC_RCTL_ACK_1; 1158 fh->fh_type = FC_TYPE_BLS; 1159 1160 /* 1161 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22). 1162 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT. 1163 * Bits 9-8 are meaningful (retransmitted or unidirectional). 1164 * Last ACK uses bits 7-6 (continue sequence), 1165 * bits 5-4 are meaningful (what kind of ACK to use). 1166 */ 1167 rx_fh = fc_frame_header_get(rx_fp); 1168 f_ctl = ntoh24(rx_fh->fh_f_ctl); 1169 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX | 1170 FC_FC_FIRST_SEQ | FC_FC_LAST_SEQ | 1171 FC_FC_END_SEQ | FC_FC_END_CONN | FC_FC_SEQ_INIT | 1172 FC_FC_RETX_SEQ | FC_FC_UNI_TX; 1173 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX; 1174 hton24(fh->fh_f_ctl, f_ctl); 1175 1176 fc_exch_setup_hdr(ep, fp, f_ctl); 1177 fh->fh_seq_id = rx_fh->fh_seq_id; 1178 fh->fh_seq_cnt = rx_fh->fh_seq_cnt; 1179 fh->fh_parm_offset = htonl(1); /* ack single frame */ 1180 1181 fr_sof(fp) = fr_sof(rx_fp); 1182 if (f_ctl & FC_FC_END_SEQ) 1183 fr_eof(fp) = FC_EOF_T; 1184 else 1185 fr_eof(fp) = FC_EOF_N; 1186 1187 lport->tt.frame_send(lport, fp); 1188 } 1189} 1190 1191/** 1192 * fc_exch_send_ba_rjt() - Send BLS Reject 1193 * @rx_fp: The frame being rejected 1194 * @reason: The reason the frame is being rejected 1195 * @explan: The explanation for the rejection 1196 * 1197 * This is for rejecting BA_ABTS only. 1198 */ 1199static void fc_exch_send_ba_rjt(struct fc_frame *rx_fp, 1200 enum fc_ba_rjt_reason reason, 1201 enum fc_ba_rjt_explan explan) 1202{ 1203 struct fc_frame *fp; 1204 struct fc_frame_header *rx_fh; 1205 struct fc_frame_header *fh; 1206 struct fc_ba_rjt *rp; 1207 struct fc_lport *lport; 1208 unsigned int f_ctl; 1209 1210 lport = fr_dev(rx_fp); 1211 fp = fc_frame_alloc(lport, sizeof(*rp)); 1212 if (!fp) 1213 return; 1214 fh = fc_frame_header_get(fp); 1215 rx_fh = fc_frame_header_get(rx_fp); 1216 1217 memset(fh, 0, sizeof(*fh) + sizeof(*rp)); 1218 1219 rp = fc_frame_payload_get(fp, sizeof(*rp)); 1220 rp->br_reason = reason; 1221 rp->br_explan = explan; 1222 1223 /* 1224 * seq_id, cs_ctl, df_ctl and param/offset are zero. 1225 */ 1226 memcpy(fh->fh_s_id, rx_fh->fh_d_id, 3); 1227 memcpy(fh->fh_d_id, rx_fh->fh_s_id, 3); 1228 fh->fh_ox_id = rx_fh->fh_ox_id; 1229 fh->fh_rx_id = rx_fh->fh_rx_id; 1230 fh->fh_seq_cnt = rx_fh->fh_seq_cnt; 1231 fh->fh_r_ctl = FC_RCTL_BA_RJT; 1232 fh->fh_type = FC_TYPE_BLS; 1233 1234 /* 1235 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22). 1236 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT. 1237 * Bits 9-8 are meaningful (retransmitted or unidirectional). 1238 * Last ACK uses bits 7-6 (continue sequence), 1239 * bits 5-4 are meaningful (what kind of ACK to use). 1240 * Always set LAST_SEQ, END_SEQ. 1241 */ 1242 f_ctl = ntoh24(rx_fh->fh_f_ctl); 1243 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX | 1244 FC_FC_END_CONN | FC_FC_SEQ_INIT | 1245 FC_FC_RETX_SEQ | FC_FC_UNI_TX; 1246 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX; 1247 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ; 1248 f_ctl &= ~FC_FC_FIRST_SEQ; 1249 hton24(fh->fh_f_ctl, f_ctl); 1250 1251 fr_sof(fp) = fc_sof_class(fr_sof(rx_fp)); 1252 fr_eof(fp) = FC_EOF_T; 1253 if (fc_sof_needs_ack(fr_sof(fp))) 1254 fr_eof(fp) = FC_EOF_N; 1255 1256 lport->tt.frame_send(lport, fp); 1257} 1258 1259/** 1260 * fc_exch_recv_abts() - Handle an incoming ABTS 1261 * @ep: The exchange the abort was on 1262 * @rx_fp: The ABTS frame 1263 * 1264 * This would be for target mode usually, but could be due to lost 1265 * FCP transfer ready, confirm or RRQ. We always handle this as an 1266 * exchange abort, ignoring the parameter. 1267 */ 1268static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp) 1269{ 1270 struct fc_frame *fp; 1271 struct fc_ba_acc *ap; 1272 struct fc_frame_header *fh; 1273 struct fc_seq *sp; 1274 1275 if (!ep) 1276 goto reject; 1277 spin_lock_bh(&ep->ex_lock); 1278 if (ep->esb_stat & ESB_ST_COMPLETE) { 1279 spin_unlock_bh(&ep->ex_lock); 1280 goto reject; 1281 } 1282 if (!(ep->esb_stat & ESB_ST_REC_QUAL)) 1283 fc_exch_hold(ep); /* hold for REC_QUAL */ 1284 ep->esb_stat |= ESB_ST_ABNORMAL | ESB_ST_REC_QUAL; 1285 fc_exch_timer_set_locked(ep, ep->r_a_tov); 1286 1287 fp = fc_frame_alloc(ep->lp, sizeof(*ap)); 1288 if (!fp) { 1289 spin_unlock_bh(&ep->ex_lock); 1290 goto free; 1291 } 1292 fh = fc_frame_header_get(fp); 1293 ap = fc_frame_payload_get(fp, sizeof(*ap)); 1294 memset(ap, 0, sizeof(*ap)); 1295 sp = &ep->seq; 1296 ap->ba_high_seq_cnt = htons(0xffff); 1297 if (sp->ssb_stat & SSB_ST_RESP) { 1298 ap->ba_seq_id = sp->id; 1299 ap->ba_seq_id_val = FC_BA_SEQ_ID_VAL; 1300 ap->ba_high_seq_cnt = fh->fh_seq_cnt; 1301 ap->ba_low_seq_cnt = htons(sp->cnt); 1302 } 1303 sp = fc_seq_start_next_locked(sp); 1304 spin_unlock_bh(&ep->ex_lock); 1305 fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS); 1306 fc_frame_free(rx_fp); 1307 return; 1308 1309reject: 1310 fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID); 1311free: 1312 fc_frame_free(rx_fp); 1313} 1314 1315/** 1316 * fc_seq_assign() - Assign exchange and sequence for incoming request 1317 * @lport: The local port that received the request 1318 * @fp: The request frame 1319 * 1320 * On success, the sequence pointer will be returned and also in fr_seq(@fp). 1321 * A reference will be held on the exchange/sequence for the caller, which 1322 * must call fc_seq_release(). 1323 */ 1324static struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp) 1325{ 1326 struct fc_exch_mgr_anchor *ema; 1327 1328 WARN_ON(lport != fr_dev(fp)); 1329 WARN_ON(fr_seq(fp)); 1330 fr_seq(fp) = NULL; 1331 1332 list_for_each_entry(ema, &lport->ema_list, ema_list) 1333 if ((!ema->match || ema->match(fp)) && 1334 fc_seq_lookup_recip(lport, ema->mp, fp) == FC_RJT_NONE) 1335 break; 1336 return fr_seq(fp); 1337} 1338 1339/** 1340 * fc_seq_release() - Release the hold 1341 * @sp: The sequence. 1342 */ 1343static void fc_seq_release(struct fc_seq *sp) 1344{ 1345 fc_exch_release(fc_seq_exch(sp)); 1346} 1347 1348/** 1349 * fc_exch_recv_req() - Handler for an incoming request 1350 * @lport: The local port that received the request 1351 * @mp: The EM that the exchange is on 1352 * @fp: The request frame 1353 * 1354 * This is used when the other end is originating the exchange 1355 * and the sequence. 1356 */ 1357static void fc_exch_recv_req(struct fc_lport *lport, struct fc_exch_mgr *mp, 1358 struct fc_frame *fp) 1359{ 1360 struct fc_frame_header *fh = fc_frame_header_get(fp); 1361 struct fc_seq *sp = NULL; 1362 struct fc_exch *ep = NULL; 1363 enum fc_pf_rjt_reason reject; 1364 1365 /* We can have the wrong fc_lport at this point with NPIV, which is a 1366 * problem now that we know a new exchange needs to be allocated 1367 */ 1368 lport = fc_vport_id_lookup(lport, ntoh24(fh->fh_d_id)); 1369 if (!lport) { 1370 fc_frame_free(fp); 1371 return; 1372 } 1373 fr_dev(fp) = lport; 1374 1375 BUG_ON(fr_seq(fp)); /* XXX remove later */ 1376 1377 /* 1378 * If the RX_ID is 0xffff, don't allocate an exchange. 1379 * The upper-level protocol may request one later, if needed. 1380 */ 1381 if (fh->fh_rx_id == htons(FC_XID_UNKNOWN)) 1382 return lport->tt.lport_recv(lport, fp); 1383 1384 reject = fc_seq_lookup_recip(lport, mp, fp); 1385 if (reject == FC_RJT_NONE) { 1386 sp = fr_seq(fp); /* sequence will be held */ 1387 ep = fc_seq_exch(sp); 1388 fc_seq_send_ack(sp, fp); 1389 ep->encaps = fr_encaps(fp); 1390 1391 /* 1392 * Call the receive function. 1393 * 1394 * The receive function may allocate a new sequence 1395 * over the old one, so we shouldn't change the 1396 * sequence after this. 1397 * 1398 * The frame will be freed by the receive function. 1399 * If new exch resp handler is valid then call that 1400 * first. 1401 */ 1402 if (ep->resp) 1403 ep->resp(sp, fp, ep->arg); 1404 else 1405 lport->tt.lport_recv(lport, fp); 1406 fc_exch_release(ep); /* release from lookup */ 1407 } else { 1408 FC_LPORT_DBG(lport, "exch/seq lookup failed: reject %x\n", 1409 reject); 1410 fc_frame_free(fp); 1411 } 1412} 1413 1414/** 1415 * fc_exch_recv_seq_resp() - Handler for an incoming response where the other 1416 * end is the originator of the sequence that is a 1417 * response to our initial exchange 1418 * @mp: The EM that the exchange is on 1419 * @fp: The response frame 1420 */ 1421static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp) 1422{ 1423 struct fc_frame_header *fh = fc_frame_header_get(fp); 1424 struct fc_seq *sp; 1425 struct fc_exch *ep; 1426 enum fc_sof sof; 1427 u32 f_ctl; 1428 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg); 1429 void *ex_resp_arg; 1430 int rc; 1431 1432 ep = fc_exch_find(mp, ntohs(fh->fh_ox_id)); 1433 if (!ep) { 1434 atomic_inc(&mp->stats.xid_not_found); 1435 goto out; 1436 } 1437 if (ep->esb_stat & ESB_ST_COMPLETE) { 1438 atomic_inc(&mp->stats.xid_not_found); 1439 goto rel; 1440 } 1441 if (ep->rxid == FC_XID_UNKNOWN) 1442 ep->rxid = ntohs(fh->fh_rx_id); 1443 if (ep->sid != 0 && ep->sid != ntoh24(fh->fh_d_id)) { 1444 atomic_inc(&mp->stats.xid_not_found); 1445 goto rel; 1446 } 1447 if (ep->did != ntoh24(fh->fh_s_id) && 1448 ep->did != FC_FID_FLOGI) { 1449 atomic_inc(&mp->stats.xid_not_found); 1450 goto rel; 1451 } 1452 sof = fr_sof(fp); 1453 sp = &ep->seq; 1454 if (fc_sof_is_init(sof)) { 1455 sp->ssb_stat |= SSB_ST_RESP; 1456 sp->id = fh->fh_seq_id; 1457 } else if (sp->id != fh->fh_seq_id) { 1458 atomic_inc(&mp->stats.seq_not_found); 1459 goto rel; 1460 } 1461 1462 f_ctl = ntoh24(fh->fh_f_ctl); 1463 fr_seq(fp) = sp; 1464 if (f_ctl & FC_FC_SEQ_INIT) 1465 ep->esb_stat |= ESB_ST_SEQ_INIT; 1466 1467 if (fc_sof_needs_ack(sof)) 1468 fc_seq_send_ack(sp, fp); 1469 resp = ep->resp; 1470 ex_resp_arg = ep->arg; 1471 1472 if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T && 1473 (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) == 1474 (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) { 1475 spin_lock_bh(&ep->ex_lock); 1476 resp = ep->resp; 1477 rc = fc_exch_done_locked(ep); 1478 WARN_ON(fc_seq_exch(sp) != ep); 1479 spin_unlock_bh(&ep->ex_lock); 1480 if (!rc) 1481 fc_exch_delete(ep); 1482 } 1483 1484 /* 1485 * Call the receive function. 1486 * The sequence is held (has a refcnt) for us, 1487 * but not for the receive function. 1488 * 1489 * The receive function may allocate a new sequence 1490 * over the old one, so we shouldn't change the 1491 * sequence after this. 1492 * 1493 * The frame will be freed by the receive function. 1494 * If new exch resp handler is valid then call that 1495 * first. 1496 */ 1497 if (resp) 1498 resp(sp, fp, ex_resp_arg); 1499 else 1500 fc_frame_free(fp); 1501 fc_exch_release(ep); 1502 return; 1503rel: 1504 fc_exch_release(ep); 1505out: 1506 fc_frame_free(fp); 1507} 1508 1509/** 1510 * fc_exch_recv_resp() - Handler for a sequence where other end is 1511 * responding to our sequence 1512 * @mp: The EM that the exchange is on 1513 * @fp: The response frame 1514 */ 1515static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp) 1516{ 1517 struct fc_seq *sp; 1518 1519 sp = fc_seq_lookup_orig(mp, fp); /* doesn't hold sequence */ 1520 1521 if (!sp) 1522 atomic_inc(&mp->stats.xid_not_found); 1523 else 1524 atomic_inc(&mp->stats.non_bls_resp); 1525 1526 fc_frame_free(fp); 1527} 1528 1529/** 1530 * fc_exch_abts_resp() - Handler for a response to an ABT 1531 * @ep: The exchange that the frame is on 1532 * @fp: The response frame 1533 * 1534 * This response would be to an ABTS cancelling an exchange or sequence. 1535 * The response can be either BA_ACC or BA_RJT 1536 */ 1537static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp) 1538{ 1539 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg); 1540 void *ex_resp_arg; 1541 struct fc_frame_header *fh; 1542 struct fc_ba_acc *ap; 1543 struct fc_seq *sp; 1544 u16 low; 1545 u16 high; 1546 int rc = 1, has_rec = 0; 1547 1548 fh = fc_frame_header_get(fp); 1549 FC_EXCH_DBG(ep, "exch: BLS rctl %x - %s\n", fh->fh_r_ctl, 1550 fc_exch_rctl_name(fh->fh_r_ctl)); 1551 1552 if (cancel_delayed_work_sync(&ep->timeout_work)) 1553 fc_exch_release(ep); /* release from pending timer hold */ 1554 1555 spin_lock_bh(&ep->ex_lock); 1556 switch (fh->fh_r_ctl) { 1557 case FC_RCTL_BA_ACC: 1558 ap = fc_frame_payload_get(fp, sizeof(*ap)); 1559 if (!ap) 1560 break; 1561 1562 /* 1563 * Decide whether to establish a Recovery Qualifier. 1564 * We do this if there is a non-empty SEQ_CNT range and 1565 * SEQ_ID is the same as the one we aborted. 1566 */ 1567 low = ntohs(ap->ba_low_seq_cnt); 1568 high = ntohs(ap->ba_high_seq_cnt); 1569 if ((ep->esb_stat & ESB_ST_REC_QUAL) == 0 && 1570 (ap->ba_seq_id_val != FC_BA_SEQ_ID_VAL || 1571 ap->ba_seq_id == ep->seq_id) && low != high) { 1572 ep->esb_stat |= ESB_ST_REC_QUAL; 1573 fc_exch_hold(ep); /* hold for recovery qualifier */ 1574 has_rec = 1; 1575 } 1576 break; 1577 case FC_RCTL_BA_RJT: 1578 break; 1579 default: 1580 break; 1581 } 1582 1583 resp = ep->resp; 1584 ex_resp_arg = ep->arg; 1585 1586 /* do we need to do some other checks here. Can we reuse more of 1587 * fc_exch_recv_seq_resp 1588 */ 1589 sp = &ep->seq; 1590 /* 1591 * do we want to check END_SEQ as well as LAST_SEQ here? 1592 */ 1593 if (ep->fh_type != FC_TYPE_FCP && 1594 ntoh24(fh->fh_f_ctl) & FC_FC_LAST_SEQ) 1595 rc = fc_exch_done_locked(ep); 1596 spin_unlock_bh(&ep->ex_lock); 1597 if (!rc) 1598 fc_exch_delete(ep); 1599 1600 if (resp) 1601 resp(sp, fp, ex_resp_arg); 1602 else 1603 fc_frame_free(fp); 1604 1605 if (has_rec) 1606 fc_exch_timer_set(ep, ep->r_a_tov); 1607 1608} 1609 1610/** 1611 * fc_exch_recv_bls() - Handler for a BLS sequence 1612 * @mp: The EM that the exchange is on 1613 * @fp: The request frame 1614 * 1615 * The BLS frame is always a sequence initiated by the remote side. 1616 * We may be either the originator or recipient of the exchange. 1617 */ 1618static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp) 1619{ 1620 struct fc_frame_header *fh; 1621 struct fc_exch *ep; 1622 u32 f_ctl; 1623 1624 fh = fc_frame_header_get(fp); 1625 f_ctl = ntoh24(fh->fh_f_ctl); 1626 fr_seq(fp) = NULL; 1627 1628 ep = fc_exch_find(mp, (f_ctl & FC_FC_EX_CTX) ? 1629 ntohs(fh->fh_ox_id) : ntohs(fh->fh_rx_id)); 1630 if (ep && (f_ctl & FC_FC_SEQ_INIT)) { 1631 spin_lock_bh(&ep->ex_lock); 1632 ep->esb_stat |= ESB_ST_SEQ_INIT; 1633 spin_unlock_bh(&ep->ex_lock); 1634 } 1635 if (f_ctl & FC_FC_SEQ_CTX) { 1636 /* 1637 * A response to a sequence we initiated. 1638 * This should only be ACKs for class 2 or F. 1639 */ 1640 switch (fh->fh_r_ctl) { 1641 case FC_RCTL_ACK_1: 1642 case FC_RCTL_ACK_0: 1643 break; 1644 default: 1645 FC_EXCH_DBG(ep, "BLS rctl %x - %s received", 1646 fh->fh_r_ctl, 1647 fc_exch_rctl_name(fh->fh_r_ctl)); 1648 break; 1649 } 1650 fc_frame_free(fp); 1651 } else { 1652 switch (fh->fh_r_ctl) { 1653 case FC_RCTL_BA_RJT: 1654 case FC_RCTL_BA_ACC: 1655 if (ep) 1656 fc_exch_abts_resp(ep, fp); 1657 else 1658 fc_frame_free(fp); 1659 break; 1660 case FC_RCTL_BA_ABTS: 1661 fc_exch_recv_abts(ep, fp); 1662 break; 1663 default: /* ignore junk */ 1664 fc_frame_free(fp); 1665 break; 1666 } 1667 } 1668 if (ep) 1669 fc_exch_release(ep); /* release hold taken by fc_exch_find */ 1670} 1671 1672/** 1673 * fc_seq_ls_acc() - Accept sequence with LS_ACC 1674 * @rx_fp: The received frame, not freed here. 1675 * 1676 * If this fails due to allocation or transmit congestion, assume the 1677 * originator will repeat the sequence. 1678 */ 1679static void fc_seq_ls_acc(struct fc_frame *rx_fp) 1680{ 1681 struct fc_lport *lport; 1682 struct fc_els_ls_acc *acc; 1683 struct fc_frame *fp; 1684 1685 lport = fr_dev(rx_fp); 1686 fp = fc_frame_alloc(lport, sizeof(*acc)); 1687 if (!fp) 1688 return; 1689 acc = fc_frame_payload_get(fp, sizeof(*acc)); 1690 memset(acc, 0, sizeof(*acc)); 1691 acc->la_cmd = ELS_LS_ACC; 1692 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0); 1693 lport->tt.frame_send(lport, fp); 1694} 1695 1696/** 1697 * fc_seq_ls_rjt() - Reject a sequence with ELS LS_RJT 1698 * @rx_fp: The received frame, not freed here. 1699 * @reason: The reason the sequence is being rejected 1700 * @explan: The explanation for the rejection 1701 * 1702 * If this fails due to allocation or transmit congestion, assume the 1703 * originator will repeat the sequence. 1704 */ 1705static void fc_seq_ls_rjt(struct fc_frame *rx_fp, enum fc_els_rjt_reason reason, 1706 enum fc_els_rjt_explan explan) 1707{ 1708 struct fc_lport *lport; 1709 struct fc_els_ls_rjt *rjt; 1710 struct fc_frame *fp; 1711 1712 lport = fr_dev(rx_fp); 1713 fp = fc_frame_alloc(lport, sizeof(*rjt)); 1714 if (!fp) 1715 return; 1716 rjt = fc_frame_payload_get(fp, sizeof(*rjt)); 1717 memset(rjt, 0, sizeof(*rjt)); 1718 rjt->er_cmd = ELS_LS_RJT; 1719 rjt->er_reason = reason; 1720 rjt->er_explan = explan; 1721 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0); 1722 lport->tt.frame_send(lport, fp); 1723} 1724 1725/** 1726 * fc_exch_reset() - Reset an exchange 1727 * @ep: The exchange to be reset 1728 */ 1729static void fc_exch_reset(struct fc_exch *ep) 1730{ 1731 struct fc_seq *sp; 1732 void (*resp)(struct fc_seq *, struct fc_frame *, void *); 1733 void *arg; 1734 int rc = 1; 1735 1736 spin_lock_bh(&ep->ex_lock); 1737 fc_exch_abort_locked(ep, 0); 1738 ep->state |= FC_EX_RST_CLEANUP; 1739 if (cancel_delayed_work(&ep->timeout_work)) 1740 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */ 1741 resp = ep->resp; 1742 ep->resp = NULL; 1743 if (ep->esb_stat & ESB_ST_REC_QUAL) 1744 atomic_dec(&ep->ex_refcnt); /* drop hold for rec_qual */ 1745 ep->esb_stat &= ~ESB_ST_REC_QUAL; 1746 arg = ep->arg; 1747 sp = &ep->seq; 1748 rc = fc_exch_done_locked(ep); 1749 spin_unlock_bh(&ep->ex_lock); 1750 if (!rc) 1751 fc_exch_delete(ep); 1752 1753 if (resp) 1754 resp(sp, ERR_PTR(-FC_EX_CLOSED), arg); 1755} 1756 1757/** 1758 * fc_exch_pool_reset() - Reset a per cpu exchange pool 1759 * @lport: The local port that the exchange pool is on 1760 * @pool: The exchange pool to be reset 1761 * @sid: The source ID 1762 * @did: The destination ID 1763 * 1764 * Resets a per cpu exches pool, releasing all of its sequences 1765 * and exchanges. If sid is non-zero then reset only exchanges 1766 * we sourced from the local port's FID. If did is non-zero then 1767 * only reset exchanges destined for the local port's FID. 1768 */ 1769static void fc_exch_pool_reset(struct fc_lport *lport, 1770 struct fc_exch_pool *pool, 1771 u32 sid, u32 did) 1772{ 1773 struct fc_exch *ep; 1774 struct fc_exch *next; 1775 1776 spin_lock_bh(&pool->lock); 1777restart: 1778 list_for_each_entry_safe(ep, next, &pool->ex_list, ex_list) { 1779 if ((lport == ep->lp) && 1780 (sid == 0 || sid == ep->sid) && 1781 (did == 0 || did == ep->did)) { 1782 fc_exch_hold(ep); 1783 spin_unlock_bh(&pool->lock); 1784 1785 fc_exch_reset(ep); 1786 1787 fc_exch_release(ep); 1788 spin_lock_bh(&pool->lock); 1789 1790 /* 1791 * must restart loop incase while lock 1792 * was down multiple eps were released. 1793 */ 1794 goto restart; 1795 } 1796 } 1797 pool->next_index = 0; 1798 pool->left = FC_XID_UNKNOWN; 1799 pool->right = FC_XID_UNKNOWN; 1800 spin_unlock_bh(&pool->lock); 1801} 1802 1803/** 1804 * fc_exch_mgr_reset() - Reset all EMs of a local port 1805 * @lport: The local port whose EMs are to be reset 1806 * @sid: The source ID 1807 * @did: The destination ID 1808 * 1809 * Reset all EMs associated with a given local port. Release all 1810 * sequences and exchanges. If sid is non-zero then reset only the 1811 * exchanges sent from the local port's FID. If did is non-zero then 1812 * reset only exchanges destined for the local port's FID. 1813 */ 1814void fc_exch_mgr_reset(struct fc_lport *lport, u32 sid, u32 did) 1815{ 1816 struct fc_exch_mgr_anchor *ema; 1817 unsigned int cpu; 1818 1819 list_for_each_entry(ema, &lport->ema_list, ema_list) { 1820 for_each_possible_cpu(cpu) 1821 fc_exch_pool_reset(lport, 1822 per_cpu_ptr(ema->mp->pool, cpu), 1823 sid, did); 1824 } 1825} 1826EXPORT_SYMBOL(fc_exch_mgr_reset); 1827 1828/** 1829 * fc_exch_lookup() - find an exchange 1830 * @lport: The local port 1831 * @xid: The exchange ID 1832 * 1833 * Returns exchange pointer with hold for caller, or NULL if not found. 1834 */ 1835static struct fc_exch *fc_exch_lookup(struct fc_lport *lport, u32 xid) 1836{ 1837 struct fc_exch_mgr_anchor *ema; 1838 1839 list_for_each_entry(ema, &lport->ema_list, ema_list) 1840 if (ema->mp->min_xid <= xid && xid <= ema->mp->max_xid) 1841 return fc_exch_find(ema->mp, xid); 1842 return NULL; 1843} 1844 1845/** 1846 * fc_exch_els_rec() - Handler for ELS REC (Read Exchange Concise) requests 1847 * @rfp: The REC frame, not freed here. 1848 * 1849 * Note that the requesting port may be different than the S_ID in the request. 1850 */ 1851static void fc_exch_els_rec(struct fc_frame *rfp) 1852{ 1853 struct fc_lport *lport; 1854 struct fc_frame *fp; 1855 struct fc_exch *ep; 1856 struct fc_els_rec *rp; 1857 struct fc_els_rec_acc *acc; 1858 enum fc_els_rjt_reason reason = ELS_RJT_LOGIC; 1859 enum fc_els_rjt_explan explan; 1860 u32 sid; 1861 u16 rxid; 1862 u16 oxid; 1863 1864 lport = fr_dev(rfp); 1865 rp = fc_frame_payload_get(rfp, sizeof(*rp)); 1866 explan = ELS_EXPL_INV_LEN; 1867 if (!rp) 1868 goto reject; 1869 sid = ntoh24(rp->rec_s_id); 1870 rxid = ntohs(rp->rec_rx_id); 1871 oxid = ntohs(rp->rec_ox_id); 1872 1873 ep = fc_exch_lookup(lport, 1874 sid == fc_host_port_id(lport->host) ? oxid : rxid); 1875 explan = ELS_EXPL_OXID_RXID; 1876 if (!ep) 1877 goto reject; 1878 if (ep->oid != sid || oxid != ep->oxid) 1879 goto rel; 1880 if (rxid != FC_XID_UNKNOWN && rxid != ep->rxid) 1881 goto rel; 1882 fp = fc_frame_alloc(lport, sizeof(*acc)); 1883 if (!fp) 1884 goto out; 1885 1886 acc = fc_frame_payload_get(fp, sizeof(*acc)); 1887 memset(acc, 0, sizeof(*acc)); 1888 acc->reca_cmd = ELS_LS_ACC; 1889 acc->reca_ox_id = rp->rec_ox_id; 1890 memcpy(acc->reca_ofid, rp->rec_s_id, 3); 1891 acc->reca_rx_id = htons(ep->rxid); 1892 if (ep->sid == ep->oid) 1893 hton24(acc->reca_rfid, ep->did); 1894 else 1895 hton24(acc->reca_rfid, ep->sid); 1896 acc->reca_fc4value = htonl(ep->seq.rec_data); 1897 acc->reca_e_stat = htonl(ep->esb_stat & (ESB_ST_RESP | 1898 ESB_ST_SEQ_INIT | 1899 ESB_ST_COMPLETE)); 1900 fc_fill_reply_hdr(fp, rfp, FC_RCTL_ELS_REP, 0); 1901 lport->tt.frame_send(lport, fp); 1902out: 1903 fc_exch_release(ep); 1904 return; 1905 1906rel: 1907 fc_exch_release(ep); 1908reject: 1909 fc_seq_ls_rjt(rfp, reason, explan); 1910} 1911 1912/** 1913 * fc_exch_rrq_resp() - Handler for RRQ responses 1914 * @sp: The sequence that the RRQ is on 1915 * @fp: The RRQ frame 1916 * @arg: The exchange that the RRQ is on 1917 * 1918 * TODO: fix error handler. 1919 */ 1920static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg) 1921{ 1922 struct fc_exch *aborted_ep = arg; 1923 unsigned int op; 1924 1925 if (IS_ERR(fp)) { 1926 int err = PTR_ERR(fp); 1927 1928 if (err == -FC_EX_CLOSED || err == -FC_EX_TIMEOUT) 1929 goto cleanup; 1930 FC_EXCH_DBG(aborted_ep, "Cannot process RRQ, " 1931 "frame error %d\n", err); 1932 return; 1933 } 1934 1935 op = fc_frame_payload_op(fp); 1936 fc_frame_free(fp); 1937 1938 switch (op) { 1939 case ELS_LS_RJT: 1940 FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ"); 1941 /* fall through */ 1942 case ELS_LS_ACC: 1943 goto cleanup; 1944 default: 1945 FC_EXCH_DBG(aborted_ep, "unexpected response op %x " 1946 "for RRQ", op); 1947 return; 1948 } 1949 1950cleanup: 1951 fc_exch_done(&aborted_ep->seq); 1952 /* drop hold for rec qual */ 1953 fc_exch_release(aborted_ep); 1954} 1955 1956 1957/** 1958 * fc_exch_seq_send() - Send a frame using a new exchange and sequence 1959 * @lport: The local port to send the frame on 1960 * @fp: The frame to be sent 1961 * @resp: The response handler for this request 1962 * @destructor: The destructor for the exchange 1963 * @arg: The argument to be passed to the response handler 1964 * @timer_msec: The timeout period for the exchange 1965 * 1966 * The frame pointer with some of the header's fields must be 1967 * filled before calling this routine, those fields are: 1968 * 1969 * - routing control 1970 * - FC port did 1971 * - FC port sid 1972 * - FC header type 1973 * - frame control 1974 * - parameter or relative offset 1975 */ 1976static struct fc_seq *fc_exch_seq_send(struct fc_lport *lport, 1977 struct fc_frame *fp, 1978 void (*resp)(struct fc_seq *, 1979 struct fc_frame *fp, 1980 void *arg), 1981 void (*destructor)(struct fc_seq *, 1982 void *), 1983 void *arg, u32 timer_msec) 1984{ 1985 struct fc_exch *ep; 1986 struct fc_seq *sp = NULL; 1987 struct fc_frame_header *fh; 1988 struct fc_fcp_pkt *fsp = NULL; 1989 int rc = 1; 1990 1991 ep = fc_exch_alloc(lport, fp); 1992 if (!ep) { 1993 fc_frame_free(fp); 1994 return NULL; 1995 } 1996 ep->esb_stat |= ESB_ST_SEQ_INIT; 1997 fh = fc_frame_header_get(fp); 1998 fc_exch_set_addr(ep, ntoh24(fh->fh_s_id), ntoh24(fh->fh_d_id)); 1999 ep->resp = resp; 2000 ep->destructor = destructor; 2001 ep->arg = arg; 2002 ep->r_a_tov = FC_DEF_R_A_TOV; 2003 ep->lp = lport; 2004 sp = &ep->seq; 2005 2006 ep->fh_type = fh->fh_type; /* save for possbile timeout handling */ 2007 ep->f_ctl = ntoh24(fh->fh_f_ctl); 2008 fc_exch_setup_hdr(ep, fp, ep->f_ctl); 2009 sp->cnt++; 2010 2011 if (ep->xid <= lport->lro_xid && fh->fh_r_ctl == FC_RCTL_DD_UNSOL_CMD) { 2012 fsp = fr_fsp(fp); 2013 fc_fcp_ddp_setup(fr_fsp(fp), ep->xid); 2014 } 2015 2016 if (unlikely(lport->tt.frame_send(lport, fp))) 2017 goto err; 2018 2019 if (timer_msec) 2020 fc_exch_timer_set_locked(ep, timer_msec); 2021 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not first seq */ 2022 2023 if (ep->f_ctl & FC_FC_SEQ_INIT) 2024 ep->esb_stat &= ~ESB_ST_SEQ_INIT; 2025 spin_unlock_bh(&ep->ex_lock); 2026 return sp; 2027err: 2028 if (fsp) 2029 fc_fcp_ddp_done(fsp); 2030 rc = fc_exch_done_locked(ep); 2031 spin_unlock_bh(&ep->ex_lock); 2032 if (!rc) 2033 fc_exch_delete(ep); 2034 return NULL; 2035} 2036 2037/** 2038 * fc_exch_rrq() - Send an ELS RRQ (Reinstate Recovery Qualifier) command 2039 * @ep: The exchange to send the RRQ on 2040 * 2041 * This tells the remote port to stop blocking the use of 2042 * the exchange and the seq_cnt range. 2043 */ 2044static void fc_exch_rrq(struct fc_exch *ep) 2045{ 2046 struct fc_lport *lport; 2047 struct fc_els_rrq *rrq; 2048 struct fc_frame *fp; 2049 u32 did; 2050 2051 lport = ep->lp; 2052 2053 fp = fc_frame_alloc(lport, sizeof(*rrq)); 2054 if (!fp) 2055 goto retry; 2056 2057 rrq = fc_frame_payload_get(fp, sizeof(*rrq)); 2058 memset(rrq, 0, sizeof(*rrq)); 2059 rrq->rrq_cmd = ELS_RRQ; 2060 hton24(rrq->rrq_s_id, ep->sid); 2061 rrq->rrq_ox_id = htons(ep->oxid); 2062 rrq->rrq_rx_id = htons(ep->rxid); 2063 2064 did = ep->did; 2065 if (ep->esb_stat & ESB_ST_RESP) 2066 did = ep->sid; 2067 2068 fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, did, 2069 lport->port_id, FC_TYPE_ELS, 2070 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0); 2071 2072 if (fc_exch_seq_send(lport, fp, fc_exch_rrq_resp, NULL, ep, 2073 lport->e_d_tov)) 2074 return; 2075 2076retry: 2077 spin_lock_bh(&ep->ex_lock); 2078 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) { 2079 spin_unlock_bh(&ep->ex_lock); 2080 /* drop hold for rec qual */ 2081 fc_exch_release(ep); 2082 return; 2083 } 2084 ep->esb_stat |= ESB_ST_REC_QUAL; 2085 fc_exch_timer_set_locked(ep, ep->r_a_tov); 2086 spin_unlock_bh(&ep->ex_lock); 2087} 2088 2089/** 2090 * fc_exch_els_rrq() - Handler for ELS RRQ (Reset Recovery Qualifier) requests 2091 * @fp: The RRQ frame, not freed here. 2092 */ 2093static void fc_exch_els_rrq(struct fc_frame *fp) 2094{ 2095 struct fc_lport *lport; 2096 struct fc_exch *ep = NULL; /* request or subject exchange */ 2097 struct fc_els_rrq *rp; 2098 u32 sid; 2099 u16 xid; 2100 enum fc_els_rjt_explan explan; 2101 2102 lport = fr_dev(fp); 2103 rp = fc_frame_payload_get(fp, sizeof(*rp)); 2104 explan = ELS_EXPL_INV_LEN; 2105 if (!rp) 2106 goto reject; 2107 2108 /* 2109 * lookup subject exchange. 2110 */ 2111 sid = ntoh24(rp->rrq_s_id); /* subject source */ 2112 xid = fc_host_port_id(lport->host) == sid ? 2113 ntohs(rp->rrq_ox_id) : ntohs(rp->rrq_rx_id); 2114 ep = fc_exch_lookup(lport, xid); 2115 explan = ELS_EXPL_OXID_RXID; 2116 if (!ep) 2117 goto reject; 2118 spin_lock_bh(&ep->ex_lock); 2119 if (ep->oxid != ntohs(rp->rrq_ox_id)) 2120 goto unlock_reject; 2121 if (ep->rxid != ntohs(rp->rrq_rx_id) && 2122 ep->rxid != FC_XID_UNKNOWN) 2123 goto unlock_reject; 2124 explan = ELS_EXPL_SID; 2125 if (ep->sid != sid) 2126 goto unlock_reject; 2127 2128 /* 2129 * Clear Recovery Qualifier state, and cancel timer if complete. 2130 */ 2131 if (ep->esb_stat & ESB_ST_REC_QUAL) { 2132 ep->esb_stat &= ~ESB_ST_REC_QUAL; 2133 atomic_dec(&ep->ex_refcnt); /* drop hold for rec qual */ 2134 } 2135 if (ep->esb_stat & ESB_ST_COMPLETE) { 2136 if (cancel_delayed_work(&ep->timeout_work)) 2137 atomic_dec(&ep->ex_refcnt); /* drop timer hold */ 2138 } 2139 2140 spin_unlock_bh(&ep->ex_lock); 2141 2142 /* 2143 * Send LS_ACC. 2144 */ 2145 fc_seq_ls_acc(fp); 2146 goto out; 2147 2148unlock_reject: 2149 spin_unlock_bh(&ep->ex_lock); 2150reject: 2151 fc_seq_ls_rjt(fp, ELS_RJT_LOGIC, explan); 2152out: 2153 if (ep) 2154 fc_exch_release(ep); /* drop hold from fc_exch_find */ 2155} 2156 2157/** 2158 * fc_exch_mgr_add() - Add an exchange manager to a local port's list of EMs 2159 * @lport: The local port to add the exchange manager to 2160 * @mp: The exchange manager to be added to the local port 2161 * @match: The match routine that indicates when this EM should be used 2162 */ 2163struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport, 2164 struct fc_exch_mgr *mp, 2165 bool (*match)(struct fc_frame *)) 2166{ 2167 struct fc_exch_mgr_anchor *ema; 2168 2169 ema = kmalloc(sizeof(*ema), GFP_ATOMIC); 2170 if (!ema) 2171 return ema; 2172 2173 ema->mp = mp; 2174 ema->match = match; 2175 /* add EM anchor to EM anchors list */ 2176 list_add_tail(&ema->ema_list, &lport->ema_list); 2177 kref_get(&mp->kref); 2178 return ema; 2179} 2180EXPORT_SYMBOL(fc_exch_mgr_add); 2181 2182/** 2183 * fc_exch_mgr_destroy() - Destroy an exchange manager 2184 * @kref: The reference to the EM to be destroyed 2185 */ 2186static void fc_exch_mgr_destroy(struct kref *kref) 2187{ 2188 struct fc_exch_mgr *mp = container_of(kref, struct fc_exch_mgr, kref); 2189 2190 mempool_destroy(mp->ep_pool); 2191 free_percpu(mp->pool); 2192 kfree(mp); 2193} 2194 2195/** 2196 * fc_exch_mgr_del() - Delete an EM from a local port's list 2197 * @ema: The exchange manager anchor identifying the EM to be deleted 2198 */ 2199void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema) 2200{ 2201 /* remove EM anchor from EM anchors list */ 2202 list_del(&ema->ema_list); 2203 kref_put(&ema->mp->kref, fc_exch_mgr_destroy); 2204 kfree(ema); 2205} 2206EXPORT_SYMBOL(fc_exch_mgr_del); 2207 2208/** 2209 * fc_exch_mgr_list_clone() - Share all exchange manager objects 2210 * @src: Source lport to clone exchange managers from 2211 * @dst: New lport that takes references to all the exchange managers 2212 */ 2213int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst) 2214{ 2215 struct fc_exch_mgr_anchor *ema, *tmp; 2216 2217 list_for_each_entry(ema, &src->ema_list, ema_list) { 2218 if (!fc_exch_mgr_add(dst, ema->mp, ema->match)) 2219 goto err; 2220 } 2221 return 0; 2222err: 2223 list_for_each_entry_safe(ema, tmp, &dst->ema_list, ema_list) 2224 fc_exch_mgr_del(ema); 2225 return -ENOMEM; 2226} 2227EXPORT_SYMBOL(fc_exch_mgr_list_clone); 2228 2229/** 2230 * fc_exch_mgr_alloc() - Allocate an exchange manager 2231 * @lport: The local port that the new EM will be associated with 2232 * @class: The default FC class for new exchanges 2233 * @min_xid: The minimum XID for exchanges from the new EM 2234 * @max_xid: The maximum XID for exchanges from the new EM 2235 * @match: The match routine for the new EM 2236 */ 2237struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lport, 2238 enum fc_class class, 2239 u16 min_xid, u16 max_xid, 2240 bool (*match)(struct fc_frame *)) 2241{ 2242 struct fc_exch_mgr *mp; 2243 u16 pool_exch_range; 2244 size_t pool_size; 2245 unsigned int cpu; 2246 struct fc_exch_pool *pool; 2247 2248 if (max_xid <= min_xid || max_xid == FC_XID_UNKNOWN || 2249 (min_xid & fc_cpu_mask) != 0) { 2250 FC_LPORT_DBG(lport, "Invalid min_xid 0x:%x and max_xid 0x:%x\n", 2251 min_xid, max_xid); 2252 return NULL; 2253 } 2254 2255 /* 2256 * allocate memory for EM 2257 */ 2258 mp = kzalloc(sizeof(struct fc_exch_mgr), GFP_ATOMIC); 2259 if (!mp) 2260 return NULL; 2261 2262 mp->class = class; 2263 /* adjust em exch xid range for offload */ 2264 mp->min_xid = min_xid; 2265 mp->max_xid = max_xid; 2266 2267 mp->ep_pool = mempool_create_slab_pool(2, fc_em_cachep); 2268 if (!mp->ep_pool) 2269 goto free_mp; 2270 2271 /* 2272 * Setup per cpu exch pool with entire exchange id range equally 2273 * divided across all cpus. The exch pointers array memory is 2274 * allocated for exch range per pool. 2275 */ 2276 pool_exch_range = (mp->max_xid - mp->min_xid + 1) / (fc_cpu_mask + 1); 2277 mp->pool_max_index = pool_exch_range - 1; 2278 2279 /* 2280 * Allocate and initialize per cpu exch pool 2281 */ 2282 pool_size = sizeof(*pool) + pool_exch_range * sizeof(struct fc_exch *); 2283 mp->pool = __alloc_percpu(pool_size, __alignof__(struct fc_exch_pool)); 2284 if (!mp->pool) 2285 goto free_mempool; 2286 for_each_possible_cpu(cpu) { 2287 pool = per_cpu_ptr(mp->pool, cpu); 2288 pool->next_index = 0; 2289 pool->left = FC_XID_UNKNOWN; 2290 pool->right = FC_XID_UNKNOWN; 2291 spin_lock_init(&pool->lock); 2292 INIT_LIST_HEAD(&pool->ex_list); 2293 } 2294 2295 kref_init(&mp->kref); 2296 if (!fc_exch_mgr_add(lport, mp, match)) { 2297 free_percpu(mp->pool); 2298 goto free_mempool; 2299 } 2300 2301 /* 2302 * Above kref_init() sets mp->kref to 1 and then 2303 * call to fc_exch_mgr_add incremented mp->kref again, 2304 * so adjust that extra increment. 2305 */ 2306 kref_put(&mp->kref, fc_exch_mgr_destroy); 2307 return mp; 2308 2309free_mempool: 2310 mempool_destroy(mp->ep_pool); 2311free_mp: 2312 kfree(mp); 2313 return NULL; 2314} 2315EXPORT_SYMBOL(fc_exch_mgr_alloc); 2316 2317/** 2318 * fc_exch_mgr_free() - Free all exchange managers on a local port 2319 * @lport: The local port whose EMs are to be freed 2320 */ 2321void fc_exch_mgr_free(struct fc_lport *lport) 2322{ 2323 struct fc_exch_mgr_anchor *ema, *next; 2324 2325 flush_workqueue(fc_exch_workqueue); 2326 list_for_each_entry_safe(ema, next, &lport->ema_list, ema_list) 2327 fc_exch_mgr_del(ema); 2328} 2329EXPORT_SYMBOL(fc_exch_mgr_free); 2330 2331/** 2332 * fc_find_ema() - Lookup and return appropriate Exchange Manager Anchor depending 2333 * upon 'xid'. 2334 * @f_ctl: f_ctl 2335 * @lport: The local port the frame was received on 2336 * @fh: The received frame header 2337 */ 2338static struct fc_exch_mgr_anchor *fc_find_ema(u32 f_ctl, 2339 struct fc_lport *lport, 2340 struct fc_frame_header *fh) 2341{ 2342 struct fc_exch_mgr_anchor *ema; 2343 u16 xid; 2344 2345 if (f_ctl & FC_FC_EX_CTX) 2346 xid = ntohs(fh->fh_ox_id); 2347 else { 2348 xid = ntohs(fh->fh_rx_id); 2349 if (xid == FC_XID_UNKNOWN) 2350 return list_entry(lport->ema_list.prev, 2351 typeof(*ema), ema_list); 2352 } 2353 2354 list_for_each_entry(ema, &lport->ema_list, ema_list) { 2355 if ((xid >= ema->mp->min_xid) && 2356 (xid <= ema->mp->max_xid)) 2357 return ema; 2358 } 2359 return NULL; 2360} 2361/** 2362 * fc_exch_recv() - Handler for received frames 2363 * @lport: The local port the frame was received on 2364 * @fp: The received frame 2365 */ 2366void fc_exch_recv(struct fc_lport *lport, struct fc_frame *fp) 2367{ 2368 struct fc_frame_header *fh = fc_frame_header_get(fp); 2369 struct fc_exch_mgr_anchor *ema; 2370 u32 f_ctl; 2371 2372 /* lport lock ? */ 2373 if (!lport || lport->state == LPORT_ST_DISABLED) { 2374 FC_LPORT_DBG(lport, "Receiving frames for an lport that " 2375 "has not been initialized correctly\n"); 2376 fc_frame_free(fp); 2377 return; 2378 } 2379 2380 f_ctl = ntoh24(fh->fh_f_ctl); 2381 ema = fc_find_ema(f_ctl, lport, fh); 2382 if (!ema) { 2383 FC_LPORT_DBG(lport, "Unable to find Exchange Manager Anchor," 2384 "fc_ctl <0x%x>, xid <0x%x>\n", 2385 f_ctl, 2386 (f_ctl & FC_FC_EX_CTX) ? 2387 ntohs(fh->fh_ox_id) : 2388 ntohs(fh->fh_rx_id)); 2389 fc_frame_free(fp); 2390 return; 2391 } 2392 2393 /* 2394 * If frame is marked invalid, just drop it. 2395 */ 2396 switch (fr_eof(fp)) { 2397 case FC_EOF_T: 2398 if (f_ctl & FC_FC_END_SEQ) 2399 skb_trim(fp_skb(fp), fr_len(fp) - FC_FC_FILL(f_ctl)); 2400 /* fall through */ 2401 case FC_EOF_N: 2402 if (fh->fh_type == FC_TYPE_BLS) 2403 fc_exch_recv_bls(ema->mp, fp); 2404 else if ((f_ctl & (FC_FC_EX_CTX | FC_FC_SEQ_CTX)) == 2405 FC_FC_EX_CTX) 2406 fc_exch_recv_seq_resp(ema->mp, fp); 2407 else if (f_ctl & FC_FC_SEQ_CTX) 2408 fc_exch_recv_resp(ema->mp, fp); 2409 else /* no EX_CTX and no SEQ_CTX */ 2410 fc_exch_recv_req(lport, ema->mp, fp); 2411 break; 2412 default: 2413 FC_LPORT_DBG(lport, "dropping invalid frame (eof %x)", 2414 fr_eof(fp)); 2415 fc_frame_free(fp); 2416 } 2417} 2418EXPORT_SYMBOL(fc_exch_recv); 2419 2420/** 2421 * fc_exch_init() - Initialize the exchange layer for a local port 2422 * @lport: The local port to initialize the exchange layer for 2423 */ 2424int fc_exch_init(struct fc_lport *lport) 2425{ 2426 if (!lport->tt.seq_start_next) 2427 lport->tt.seq_start_next = fc_seq_start_next; 2428 2429 if (!lport->tt.seq_set_resp) 2430 lport->tt.seq_set_resp = fc_seq_set_resp; 2431 2432 if (!lport->tt.exch_seq_send) 2433 lport->tt.exch_seq_send = fc_exch_seq_send; 2434 2435 if (!lport->tt.seq_send) 2436 lport->tt.seq_send = fc_seq_send; 2437 2438 if (!lport->tt.seq_els_rsp_send) 2439 lport->tt.seq_els_rsp_send = fc_seq_els_rsp_send; 2440 2441 if (!lport->tt.exch_done) 2442 lport->tt.exch_done = fc_exch_done; 2443 2444 if (!lport->tt.exch_mgr_reset) 2445 lport->tt.exch_mgr_reset = fc_exch_mgr_reset; 2446 2447 if (!lport->tt.seq_exch_abort) 2448 lport->tt.seq_exch_abort = fc_seq_exch_abort; 2449 2450 if (!lport->tt.seq_assign) 2451 lport->tt.seq_assign = fc_seq_assign; 2452 2453 if (!lport->tt.seq_release) 2454 lport->tt.seq_release = fc_seq_release; 2455 2456 return 0; 2457} 2458EXPORT_SYMBOL(fc_exch_init); 2459 2460/** 2461 * fc_setup_exch_mgr() - Setup an exchange manager 2462 */ 2463int fc_setup_exch_mgr(void) 2464{ 2465 fc_em_cachep = kmem_cache_create("libfc_em", sizeof(struct fc_exch), 2466 0, SLAB_HWCACHE_ALIGN, NULL); 2467 if (!fc_em_cachep) 2468 return -ENOMEM; 2469 2470 /* 2471 * Initialize fc_cpu_mask and fc_cpu_order. The 2472 * fc_cpu_mask is set for nr_cpu_ids rounded up 2473 * to order of 2's * power and order is stored 2474 * in fc_cpu_order as this is later required in 2475 * mapping between an exch id and exch array index 2476 * in per cpu exch pool. 2477 * 2478 * This round up is required to align fc_cpu_mask 2479 * to exchange id's lower bits such that all incoming 2480 * frames of an exchange gets delivered to the same 2481 * cpu on which exchange originated by simple bitwise 2482 * AND operation between fc_cpu_mask and exchange id. 2483 */ 2484 fc_cpu_mask = 1; 2485 fc_cpu_order = 0; 2486 while (fc_cpu_mask < nr_cpu_ids) { 2487 fc_cpu_mask <<= 1; 2488 fc_cpu_order++; 2489 } 2490 fc_cpu_mask--; 2491 2492 fc_exch_workqueue = create_singlethread_workqueue("fc_exch_workqueue"); 2493 if (!fc_exch_workqueue) 2494 goto err; 2495 return 0; 2496err: 2497 kmem_cache_destroy(fc_em_cachep); 2498 return -ENOMEM; 2499} 2500 2501/** 2502 * fc_destroy_exch_mgr() - Destroy an exchange manager 2503 */ 2504void fc_destroy_exch_mgr(void) 2505{ 2506 destroy_workqueue(fc_exch_workqueue); 2507 kmem_cache_destroy(fc_em_cachep); 2508} 2509