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
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.
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
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.
19 * Maintained at www.Open-FCoE.org
23 * Fibre Channel exchange and sequence handling.
26 #include <linux/timer.h>
27 #include <linux/slab.h>
28 #include <linux/err.h>
30 #include <scsi/fc/fc_fc2.h>
32 #include <scsi/libfc.h>
33 #include <scsi/fc_encode.h>
37 u16 fc_cpu_mask; /* cpu mask for possible cpus */
38 EXPORT_SYMBOL(fc_cpu_mask);
39 static u16 fc_cpu_order; /* 2's power to represent total possible cpus */
40 static struct kmem_cache *fc_em_cachep; /* cache for exchanges */
41 static struct workqueue_struct *fc_exch_workqueue;
44 * Structure and function definitions for managing Fibre Channel Exchanges
47 * The three primary structures used here are fc_exch_mgr, fc_exch, and fc_seq.
49 * fc_exch_mgr holds the exchange state for an N port
51 * fc_exch holds state for one exchange and links to its active sequence.
53 * fc_seq holds the state for an individual sequence.
57 * struct fc_exch_pool - Per cpu exchange pool
58 * @next_index: Next possible free exchange index
59 * @total_exches: Total allocated exchanges
60 * @lock: Exch pool lock
61 * @ex_list: List of exchanges
63 * This structure manages per cpu exchanges in array of exchange pointers.
64 * This array is allocated followed by struct fc_exch_pool memory for
65 * assigned range of exchanges to per cpu pool.
71 /* two cache of free slot in exch array */
76 struct list_head ex_list;
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
90 * This structure is the center for creating exchanges and sequences.
91 * It manages the allocation of exchange IDs.
100 struct fc_exch_pool *pool;
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
108 atomic_t no_free_exch;
109 atomic_t no_free_exch_xid;
110 atomic_t xid_not_found;
112 atomic_t seq_not_found;
113 atomic_t non_bls_resp;
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
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.
129 struct fc_exch_mgr_anchor {
130 struct list_head ema_list;
131 struct fc_exch_mgr *mp;
132 bool (*match)(struct fc_frame *);
135 static void fc_exch_rrq(struct fc_exch *);
136 static void fc_seq_ls_acc(struct fc_frame *);
137 static void fc_seq_ls_rjt(struct fc_frame *, enum fc_els_rjt_reason,
138 enum fc_els_rjt_explan);
139 static void fc_exch_els_rec(struct fc_frame *);
140 static void fc_exch_els_rrq(struct fc_frame *);
143 * Internal implementation notes.
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.
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.
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.
160 * Notes on reference counts:
162 * Exchanges are reference counted and exchange gets freed when the reference
163 * count becomes zero.
166 * Sequences are timed out for E_D_TOV and R_A_TOV.
168 * Sequence event handling:
170 * The following events may occur on initiator sequences:
173 * For now, the whole thing is sent.
175 * This applies only to class F.
176 * The sequence is marked complete.
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).
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.
192 * The following events may occur on recipient sequences:
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.
200 * Deallocate sequence
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.
211 * The EM code run in a per-CPU worker thread.
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.
222 * opcode names for debugging.
224 static char *fc_exch_rctl_names[] = FC_RCTL_NAMES_INIT;
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
232 * This routine is used to determine a human-readable string identifying
235 static inline const char *fc_exch_name_lookup(unsigned int op, char **table,
236 unsigned int max_index)
238 const char *name = NULL;
248 * fc_exch_rctl_name() - Wrapper routine for fc_exch_name_lookup()
249 * @op: The opcode to be looked up
251 static const char *fc_exch_rctl_name(unsigned int op)
253 return fc_exch_name_lookup(op, fc_exch_rctl_names,
254 ARRAY_SIZE(fc_exch_rctl_names));
258 * fc_exch_hold() - Increment an exchange's reference count
259 * @ep: Echange to be held
261 static inline void fc_exch_hold(struct fc_exch *ep)
263 atomic_inc(&ep->ex_refcnt);
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
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.
276 static void fc_exch_setup_hdr(struct fc_exch *ep, struct fc_frame *fp,
279 struct fc_frame_header *fh = fc_frame_header_get(fp);
282 fr_sof(fp) = ep->class;
284 fr_sof(fp) = fc_sof_normal(ep->class);
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;
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
296 * After this, the length will be even, as expected by
299 fill = fr_len(fp) & 3;
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);
307 WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */
308 fr_eof(fp) = FC_EOF_N;
312 * Initialize remainig fh fields
313 * from fc_fill_fc_hdr
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);
322 * fc_exch_release() - Decrement an exchange's reference count
323 * @ep: Exchange to be released
325 * If the reference count reaches zero and the exchange is complete,
328 static void fc_exch_release(struct fc_exch *ep)
330 struct fc_exch_mgr *mp;
332 if (atomic_dec_and_test(&ep->ex_refcnt)) {
335 ep->destructor(&ep->seq, ep->arg);
336 WARN_ON(!(ep->esb_stat & ESB_ST_COMPLETE));
337 mempool_free(ep, mp->ep_pool);
342 * fc_exch_done_locked() - Complete an exchange with the exchange lock held
343 * @ep: The exchange that is complete
345 static int fc_exch_done_locked(struct fc_exch *ep)
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.
356 if (ep->state & FC_EX_DONE)
358 ep->esb_stat |= ESB_ST_COMPLETE;
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 */
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
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.
378 static inline struct fc_exch *fc_exch_ptr_get(struct fc_exch_pool *pool,
381 struct fc_exch **exches = (struct fc_exch **)(pool + 1);
382 return exches[index];
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
391 static inline void fc_exch_ptr_set(struct fc_exch_pool *pool, u16 index,
394 ((struct fc_exch **)(pool + 1))[index] = ep;
398 * fc_exch_delete() - Delete an exchange
399 * @ep: The exchange to be deleted
401 static void fc_exch_delete(struct fc_exch *ep)
403 struct fc_exch_pool *pool;
407 spin_lock_bh(&pool->lock);
408 WARN_ON(pool->total_exches <= 0);
409 pool->total_exches--;
411 /* update cache of free slot */
412 index = (ep->xid - ep->em->min_xid) >> fc_cpu_order;
413 if (pool->left == FC_XID_UNKNOWN)
415 else if (pool->right == FC_XID_UNKNOWN)
418 pool->next_index = index;
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 */
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
432 * Used for upper level protocols to time out the exchange.
433 * The timer is cancelled when it fires or when the exchange completes.
435 static inline void fc_exch_timer_set_locked(struct fc_exch *ep,
436 unsigned int timer_msec)
438 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
441 FC_EXCH_DBG(ep, "Exchange timer armed\n");
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 */
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
453 static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec)
455 spin_lock_bh(&ep->ex_lock);
456 fc_exch_timer_set_locked(ep, timer_msec);
457 spin_unlock_bh(&ep->ex_lock);
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
466 static int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp,
470 struct fc_frame_header *fh = fc_frame_header_get(fp);
474 ep = fc_seq_exch(sp);
475 WARN_ON((ep->esb_stat & ESB_ST_SEQ_INIT) != ESB_ST_SEQ_INIT);
477 f_ctl = ntoh24(fh->fh_f_ctl);
478 fc_exch_setup_hdr(ep, fp, f_ctl);
479 fr_encaps(fp) = ep->encaps;
482 * update sequence count if this frame is carrying
483 * multiple FC frames when sequence offload is enabled
486 if (fr_max_payload(fp))
487 sp->cnt += DIV_ROUND_UP((fr_len(fp) - sizeof(*fh)),
495 error = lport->tt.frame_send(lport, fp);
498 * Update the exchange and sequence flags,
499 * assuming all frames for the sequence have been sent.
500 * We can only be called to send once for each sequence.
502 spin_lock_bh(&ep->ex_lock);
503 ep->f_ctl = f_ctl & ~FC_FC_FIRST_SEQ; /* not first seq */
504 if (f_ctl & FC_FC_SEQ_INIT)
505 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
506 spin_unlock_bh(&ep->ex_lock);
511 * fc_seq_alloc() - Allocate a sequence for a given exchange
512 * @ep: The exchange to allocate a new sequence for
513 * @seq_id: The sequence ID to be used
515 * We don't support multiple originated sequences on the same exchange.
516 * By implication, any previously originated sequence on this exchange
517 * is complete, and we reallocate the same sequence.
519 static struct fc_seq *fc_seq_alloc(struct fc_exch *ep, u8 seq_id)
531 * fc_seq_start_next_locked() - Allocate a new sequence on the same
532 * exchange as the supplied sequence
533 * @sp: The sequence/exchange to get a new sequence for
535 static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp)
537 struct fc_exch *ep = fc_seq_exch(sp);
539 sp = fc_seq_alloc(ep, ep->seq_id++);
540 FC_EXCH_DBG(ep, "f_ctl %6x seq %2x\n",
546 * fc_seq_start_next() - Lock the exchange and get a new sequence
547 * for a given sequence/exchange pair
548 * @sp: The sequence/exchange to get a new exchange for
550 static struct fc_seq *fc_seq_start_next(struct fc_seq *sp)
552 struct fc_exch *ep = fc_seq_exch(sp);
554 spin_lock_bh(&ep->ex_lock);
555 sp = fc_seq_start_next_locked(sp);
556 spin_unlock_bh(&ep->ex_lock);
562 * Set the response handler for the exchange associated with a sequence.
564 static void fc_seq_set_resp(struct fc_seq *sp,
565 void (*resp)(struct fc_seq *, struct fc_frame *,
569 struct fc_exch *ep = fc_seq_exch(sp);
571 spin_lock_bh(&ep->ex_lock);
574 spin_unlock_bh(&ep->ex_lock);
578 * fc_seq_exch_abort() - Abort an exchange and sequence
579 * @req_sp: The sequence to be aborted
580 * @timer_msec: The period of time to wait before aborting
582 * Generally called because of a timeout or an abort from the upper layer.
584 static int fc_seq_exch_abort(const struct fc_seq *req_sp,
585 unsigned int timer_msec)
592 ep = fc_seq_exch(req_sp);
594 spin_lock_bh(&ep->ex_lock);
595 if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL) ||
596 ep->state & (FC_EX_DONE | FC_EX_RST_CLEANUP)) {
597 spin_unlock_bh(&ep->ex_lock);
602 * Send the abort on a new sequence if possible.
604 sp = fc_seq_start_next_locked(&ep->seq);
606 spin_unlock_bh(&ep->ex_lock);
610 ep->esb_stat |= ESB_ST_SEQ_INIT | ESB_ST_ABNORMAL;
612 fc_exch_timer_set_locked(ep, timer_msec);
613 spin_unlock_bh(&ep->ex_lock);
616 * If not logged into the fabric, don't send ABTS but leave
617 * sequence active until next timeout.
623 * Send an abort for the sequence that timed out.
625 fp = fc_frame_alloc(ep->lp, 0);
627 fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid,
628 FC_TYPE_BLS, FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
629 error = fc_seq_send(ep->lp, sp, fp);
636 * fc_exch_timeout() - Handle exchange timer expiration
637 * @work: The work_struct identifying the exchange that timed out
639 static void fc_exch_timeout(struct work_struct *work)
641 struct fc_exch *ep = container_of(work, struct fc_exch,
643 struct fc_seq *sp = &ep->seq;
644 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
649 FC_EXCH_DBG(ep, "Exchange timed out\n");
651 spin_lock_bh(&ep->ex_lock);
652 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
655 e_stat = ep->esb_stat;
656 if (e_stat & ESB_ST_COMPLETE) {
657 ep->esb_stat = e_stat & ~ESB_ST_REC_QUAL;
658 spin_unlock_bh(&ep->ex_lock);
659 if (e_stat & ESB_ST_REC_QUAL)
666 if (e_stat & ESB_ST_ABNORMAL)
667 rc = fc_exch_done_locked(ep);
668 spin_unlock_bh(&ep->ex_lock);
672 resp(sp, ERR_PTR(-FC_EX_TIMEOUT), arg);
673 fc_seq_exch_abort(sp, 2 * ep->r_a_tov);
677 spin_unlock_bh(&ep->ex_lock);
680 * This release matches the hold taken when the timer was set.
686 * fc_exch_em_alloc() - Allocate an exchange from a specified EM.
687 * @lport: The local port that the exchange is for
688 * @mp: The exchange manager that will allocate the exchange
690 * Returns pointer to allocated fc_exch with exch lock held.
692 static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport,
693 struct fc_exch_mgr *mp)
698 struct fc_exch_pool *pool;
700 /* allocate memory for exchange */
701 ep = mempool_alloc(mp->ep_pool, GFP_ATOMIC);
703 atomic_inc(&mp->stats.no_free_exch);
706 memset(ep, 0, sizeof(*ep));
709 pool = per_cpu_ptr(mp->pool, cpu);
710 spin_lock_bh(&pool->lock);
713 /* peek cache of free slot */
714 if (pool->left != FC_XID_UNKNOWN) {
716 pool->left = FC_XID_UNKNOWN;
719 if (pool->right != FC_XID_UNKNOWN) {
721 pool->right = FC_XID_UNKNOWN;
725 index = pool->next_index;
726 /* allocate new exch from pool */
727 while (fc_exch_ptr_get(pool, index)) {
728 index = index == mp->pool_max_index ? 0 : index + 1;
729 if (index == pool->next_index)
732 pool->next_index = index == mp->pool_max_index ? 0 : index + 1;
734 fc_exch_hold(ep); /* hold for exch in mp */
735 spin_lock_init(&ep->ex_lock);
737 * Hold exch lock for caller to prevent fc_exch_reset()
738 * from releasing exch while fc_exch_alloc() caller is
739 * still working on exch.
741 spin_lock_bh(&ep->ex_lock);
743 fc_exch_ptr_set(pool, index, ep);
744 list_add_tail(&ep->ex_list, &pool->ex_list);
745 fc_seq_alloc(ep, ep->seq_id++);
746 pool->total_exches++;
747 spin_unlock_bh(&pool->lock);
752 ep->oxid = ep->xid = (index << fc_cpu_order | cpu) + mp->min_xid;
756 ep->f_ctl = FC_FC_FIRST_SEQ; /* next seq is first seq */
757 ep->rxid = FC_XID_UNKNOWN;
758 ep->class = mp->class;
759 INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout);
763 spin_unlock_bh(&pool->lock);
764 atomic_inc(&mp->stats.no_free_exch_xid);
765 mempool_free(ep, mp->ep_pool);
770 * fc_exch_alloc() - Allocate an exchange from an EM on a
771 * local port's list of EMs.
772 * @lport: The local port that will own the exchange
773 * @fp: The FC frame that the exchange will be for
775 * This function walks the list of exchange manager(EM)
776 * anchors to select an EM for a new exchange allocation. The
777 * EM is selected when a NULL match function pointer is encountered
778 * or when a call to a match function returns true.
780 static inline struct fc_exch *fc_exch_alloc(struct fc_lport *lport,
783 struct fc_exch_mgr_anchor *ema;
785 list_for_each_entry(ema, &lport->ema_list, ema_list)
786 if (!ema->match || ema->match(fp))
787 return fc_exch_em_alloc(lport, ema->mp);
792 * fc_exch_find() - Lookup and hold an exchange
793 * @mp: The exchange manager to lookup the exchange from
794 * @xid: The XID of the exchange to look up
796 static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid)
798 struct fc_exch_pool *pool;
799 struct fc_exch *ep = NULL;
801 if ((xid >= mp->min_xid) && (xid <= mp->max_xid)) {
802 pool = per_cpu_ptr(mp->pool, xid & fc_cpu_mask);
803 spin_lock_bh(&pool->lock);
804 ep = fc_exch_ptr_get(pool, (xid - mp->min_xid) >> fc_cpu_order);
807 WARN_ON(ep->xid != xid);
809 spin_unlock_bh(&pool->lock);
816 * fc_exch_done() - Indicate that an exchange/sequence tuple is complete and
817 * the memory allocated for the related objects may be freed.
818 * @sp: The sequence that has completed
820 static void fc_exch_done(struct fc_seq *sp)
822 struct fc_exch *ep = fc_seq_exch(sp);
825 spin_lock_bh(&ep->ex_lock);
826 rc = fc_exch_done_locked(ep);
827 spin_unlock_bh(&ep->ex_lock);
833 * fc_exch_resp() - Allocate a new exchange for a response frame
834 * @lport: The local port that the exchange was for
835 * @mp: The exchange manager to allocate the exchange from
836 * @fp: The response frame
838 * Sets the responder ID in the frame header.
840 static struct fc_exch *fc_exch_resp(struct fc_lport *lport,
841 struct fc_exch_mgr *mp,
845 struct fc_frame_header *fh;
847 ep = fc_exch_alloc(lport, fp);
849 ep->class = fc_frame_class(fp);
852 * Set EX_CTX indicating we're responding on this exchange.
854 ep->f_ctl |= FC_FC_EX_CTX; /* we're responding */
855 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not new */
856 fh = fc_frame_header_get(fp);
857 ep->sid = ntoh24(fh->fh_d_id);
858 ep->did = ntoh24(fh->fh_s_id);
862 * Allocated exchange has placed the XID in the
863 * originator field. Move it to the responder field,
864 * and set the originator XID from the frame.
867 ep->oxid = ntohs(fh->fh_ox_id);
868 ep->esb_stat |= ESB_ST_RESP | ESB_ST_SEQ_INIT;
869 if ((ntoh24(fh->fh_f_ctl) & FC_FC_SEQ_INIT) == 0)
870 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
872 fc_exch_hold(ep); /* hold for caller */
873 spin_unlock_bh(&ep->ex_lock); /* lock from fc_exch_alloc */
879 * fc_seq_lookup_recip() - Find a sequence where the other end
880 * originated the sequence
881 * @lport: The local port that the frame was sent to
882 * @mp: The Exchange Manager to lookup the exchange from
883 * @fp: The frame associated with the sequence we're looking for
885 * If fc_pf_rjt_reason is FC_RJT_NONE then this function will have a hold
886 * on the ep that should be released by the caller.
888 static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport,
889 struct fc_exch_mgr *mp,
892 struct fc_frame_header *fh = fc_frame_header_get(fp);
893 struct fc_exch *ep = NULL;
894 struct fc_seq *sp = NULL;
895 enum fc_pf_rjt_reason reject = FC_RJT_NONE;
899 f_ctl = ntoh24(fh->fh_f_ctl);
900 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != 0);
903 * Lookup or create the exchange if we will be creating the sequence.
905 if (f_ctl & FC_FC_EX_CTX) {
906 xid = ntohs(fh->fh_ox_id); /* we originated exch */
907 ep = fc_exch_find(mp, xid);
909 atomic_inc(&mp->stats.xid_not_found);
910 reject = FC_RJT_OX_ID;
913 if (ep->rxid == FC_XID_UNKNOWN)
914 ep->rxid = ntohs(fh->fh_rx_id);
915 else if (ep->rxid != ntohs(fh->fh_rx_id)) {
916 reject = FC_RJT_OX_ID;
920 xid = ntohs(fh->fh_rx_id); /* we are the responder */
923 * Special case for MDS issuing an ELS TEST with a
925 * XXX take this out once we do the proper reject.
927 if (xid == 0 && fh->fh_r_ctl == FC_RCTL_ELS_REQ &&
928 fc_frame_payload_op(fp) == ELS_TEST) {
929 fh->fh_rx_id = htons(FC_XID_UNKNOWN);
930 xid = FC_XID_UNKNOWN;
934 * new sequence - find the exchange
936 ep = fc_exch_find(mp, xid);
937 if ((f_ctl & FC_FC_FIRST_SEQ) && fc_sof_is_init(fr_sof(fp))) {
939 atomic_inc(&mp->stats.xid_busy);
940 reject = FC_RJT_RX_ID;
943 ep = fc_exch_resp(lport, mp, fp);
945 reject = FC_RJT_EXCH_EST; /* XXX */
948 xid = ep->xid; /* get our XID */
950 atomic_inc(&mp->stats.xid_not_found);
951 reject = FC_RJT_RX_ID; /* XID not found */
957 * At this point, we have the exchange held.
958 * Find or create the sequence.
960 if (fc_sof_is_init(fr_sof(fp))) {
962 sp->ssb_stat |= SSB_ST_RESP;
963 sp->id = fh->fh_seq_id;
966 if (sp->id != fh->fh_seq_id) {
967 atomic_inc(&mp->stats.seq_not_found);
968 if (f_ctl & FC_FC_END_SEQ) {
970 * Update sequence_id based on incoming last
971 * frame of sequence exchange. This is needed
972 * for FCoE target where DDP has been used
973 * on target where, stack is indicated only
974 * about last frame's (payload _header) header.
975 * Whereas "seq_id" which is part of
976 * frame_header is allocated by initiator
977 * which is totally different from "seq_id"
978 * allocated when XFER_RDY was sent by target.
979 * To avoid false -ve which results into not
980 * sending RSP, hence write request on other
981 * end never finishes.
983 spin_lock_bh(&ep->ex_lock);
984 sp->ssb_stat |= SSB_ST_RESP;
985 sp->id = fh->fh_seq_id;
986 spin_unlock_bh(&ep->ex_lock);
988 /* sequence/exch should exist */
989 reject = FC_RJT_SEQ_ID;
994 WARN_ON(ep != fc_seq_exch(sp));
996 if (f_ctl & FC_FC_SEQ_INIT)
997 ep->esb_stat |= ESB_ST_SEQ_INIT;
1003 fc_exch_done(&ep->seq);
1004 fc_exch_release(ep); /* hold from fc_exch_find/fc_exch_resp */
1009 * fc_seq_lookup_orig() - Find a sequence where this end
1010 * originated the sequence
1011 * @mp: The Exchange Manager to lookup the exchange from
1012 * @fp: The frame associated with the sequence we're looking for
1014 * Does not hold the sequence for the caller.
1016 static struct fc_seq *fc_seq_lookup_orig(struct fc_exch_mgr *mp,
1017 struct fc_frame *fp)
1019 struct fc_frame_header *fh = fc_frame_header_get(fp);
1021 struct fc_seq *sp = NULL;
1025 f_ctl = ntoh24(fh->fh_f_ctl);
1026 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != FC_FC_SEQ_CTX);
1027 xid = ntohs((f_ctl & FC_FC_EX_CTX) ? fh->fh_ox_id : fh->fh_rx_id);
1028 ep = fc_exch_find(mp, xid);
1031 if (ep->seq.id == fh->fh_seq_id) {
1033 * Save the RX_ID if we didn't previously know it.
1036 if ((f_ctl & FC_FC_EX_CTX) != 0 &&
1037 ep->rxid == FC_XID_UNKNOWN) {
1038 ep->rxid = ntohs(fh->fh_rx_id);
1041 fc_exch_release(ep);
1046 * fc_exch_set_addr() - Set the source and destination IDs for an exchange
1047 * @ep: The exchange to set the addresses for
1048 * @orig_id: The originator's ID
1049 * @resp_id: The responder's ID
1051 * Note this must be done before the first sequence of the exchange is sent.
1053 static void fc_exch_set_addr(struct fc_exch *ep,
1054 u32 orig_id, u32 resp_id)
1057 if (ep->esb_stat & ESB_ST_RESP) {
1067 * fc_seq_els_rsp_send() - Send an ELS response using information from
1068 * the existing sequence/exchange.
1069 * @fp: The received frame
1070 * @els_cmd: The ELS command to be sent
1071 * @els_data: The ELS data to be sent
1073 * The received frame is not freed.
1075 static void fc_seq_els_rsp_send(struct fc_frame *fp, enum fc_els_cmd els_cmd,
1076 struct fc_seq_els_data *els_data)
1080 fc_seq_ls_rjt(fp, els_data->reason, els_data->explan);
1086 fc_exch_els_rrq(fp);
1089 fc_exch_els_rec(fp);
1092 FC_LPORT_DBG(fr_dev(fp), "Invalid ELS CMD:%x\n", els_cmd);
1097 * fc_seq_send_last() - Send a sequence that is the last in the exchange
1098 * @sp: The sequence that is to be sent
1099 * @fp: The frame that will be sent on the sequence
1100 * @rctl: The R_CTL information to be sent
1101 * @fh_type: The frame header type
1103 static void fc_seq_send_last(struct fc_seq *sp, struct fc_frame *fp,
1104 enum fc_rctl rctl, enum fc_fh_type fh_type)
1107 struct fc_exch *ep = fc_seq_exch(sp);
1109 f_ctl = FC_FC_LAST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT;
1111 fc_fill_fc_hdr(fp, rctl, ep->did, ep->sid, fh_type, f_ctl, 0);
1112 fc_seq_send(ep->lp, sp, fp);
1116 * fc_seq_send_ack() - Send an acknowledgement that we've received a frame
1117 * @sp: The sequence to send the ACK on
1118 * @rx_fp: The received frame that is being acknoledged
1120 * Send ACK_1 (or equiv.) indicating we received something.
1122 static void fc_seq_send_ack(struct fc_seq *sp, const struct fc_frame *rx_fp)
1124 struct fc_frame *fp;
1125 struct fc_frame_header *rx_fh;
1126 struct fc_frame_header *fh;
1127 struct fc_exch *ep = fc_seq_exch(sp);
1128 struct fc_lport *lport = ep->lp;
1132 * Don't send ACKs for class 3.
1134 if (fc_sof_needs_ack(fr_sof(rx_fp))) {
1135 fp = fc_frame_alloc(lport, 0);
1139 fh = fc_frame_header_get(fp);
1140 fh->fh_r_ctl = FC_RCTL_ACK_1;
1141 fh->fh_type = FC_TYPE_BLS;
1144 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
1145 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
1146 * Bits 9-8 are meaningful (retransmitted or unidirectional).
1147 * Last ACK uses bits 7-6 (continue sequence),
1148 * bits 5-4 are meaningful (what kind of ACK to use).
1150 rx_fh = fc_frame_header_get(rx_fp);
1151 f_ctl = ntoh24(rx_fh->fh_f_ctl);
1152 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
1153 FC_FC_FIRST_SEQ | FC_FC_LAST_SEQ |
1154 FC_FC_END_SEQ | FC_FC_END_CONN | FC_FC_SEQ_INIT |
1155 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
1156 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
1157 hton24(fh->fh_f_ctl, f_ctl);
1159 fc_exch_setup_hdr(ep, fp, f_ctl);
1160 fh->fh_seq_id = rx_fh->fh_seq_id;
1161 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
1162 fh->fh_parm_offset = htonl(1); /* ack single frame */
1164 fr_sof(fp) = fr_sof(rx_fp);
1165 if (f_ctl & FC_FC_END_SEQ)
1166 fr_eof(fp) = FC_EOF_T;
1168 fr_eof(fp) = FC_EOF_N;
1170 lport->tt.frame_send(lport, fp);
1175 * fc_exch_send_ba_rjt() - Send BLS Reject
1176 * @rx_fp: The frame being rejected
1177 * @reason: The reason the frame is being rejected
1178 * @explan: The explanation for the rejection
1180 * This is for rejecting BA_ABTS only.
1182 static void fc_exch_send_ba_rjt(struct fc_frame *rx_fp,
1183 enum fc_ba_rjt_reason reason,
1184 enum fc_ba_rjt_explan explan)
1186 struct fc_frame *fp;
1187 struct fc_frame_header *rx_fh;
1188 struct fc_frame_header *fh;
1189 struct fc_ba_rjt *rp;
1190 struct fc_lport *lport;
1193 lport = fr_dev(rx_fp);
1194 fp = fc_frame_alloc(lport, sizeof(*rp));
1197 fh = fc_frame_header_get(fp);
1198 rx_fh = fc_frame_header_get(rx_fp);
1200 memset(fh, 0, sizeof(*fh) + sizeof(*rp));
1202 rp = fc_frame_payload_get(fp, sizeof(*rp));
1203 rp->br_reason = reason;
1204 rp->br_explan = explan;
1207 * seq_id, cs_ctl, df_ctl and param/offset are zero.
1209 memcpy(fh->fh_s_id, rx_fh->fh_d_id, 3);
1210 memcpy(fh->fh_d_id, rx_fh->fh_s_id, 3);
1211 fh->fh_ox_id = rx_fh->fh_ox_id;
1212 fh->fh_rx_id = rx_fh->fh_rx_id;
1213 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
1214 fh->fh_r_ctl = FC_RCTL_BA_RJT;
1215 fh->fh_type = FC_TYPE_BLS;
1218 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
1219 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
1220 * Bits 9-8 are meaningful (retransmitted or unidirectional).
1221 * Last ACK uses bits 7-6 (continue sequence),
1222 * bits 5-4 are meaningful (what kind of ACK to use).
1223 * Always set LAST_SEQ, END_SEQ.
1225 f_ctl = ntoh24(rx_fh->fh_f_ctl);
1226 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
1227 FC_FC_END_CONN | FC_FC_SEQ_INIT |
1228 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
1229 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
1230 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
1231 f_ctl &= ~FC_FC_FIRST_SEQ;
1232 hton24(fh->fh_f_ctl, f_ctl);
1234 fr_sof(fp) = fc_sof_class(fr_sof(rx_fp));
1235 fr_eof(fp) = FC_EOF_T;
1236 if (fc_sof_needs_ack(fr_sof(fp)))
1237 fr_eof(fp) = FC_EOF_N;
1239 lport->tt.frame_send(lport, fp);
1243 * fc_exch_recv_abts() - Handle an incoming ABTS
1244 * @ep: The exchange the abort was on
1245 * @rx_fp: The ABTS frame
1247 * This would be for target mode usually, but could be due to lost
1248 * FCP transfer ready, confirm or RRQ. We always handle this as an
1249 * exchange abort, ignoring the parameter.
1251 static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp)
1253 struct fc_frame *fp;
1254 struct fc_ba_acc *ap;
1255 struct fc_frame_header *fh;
1260 spin_lock_bh(&ep->ex_lock);
1261 if (ep->esb_stat & ESB_ST_COMPLETE) {
1262 spin_unlock_bh(&ep->ex_lock);
1265 if (!(ep->esb_stat & ESB_ST_REC_QUAL))
1266 fc_exch_hold(ep); /* hold for REC_QUAL */
1267 ep->esb_stat |= ESB_ST_ABNORMAL | ESB_ST_REC_QUAL;
1268 fc_exch_timer_set_locked(ep, ep->r_a_tov);
1270 fp = fc_frame_alloc(ep->lp, sizeof(*ap));
1272 spin_unlock_bh(&ep->ex_lock);
1275 fh = fc_frame_header_get(fp);
1276 ap = fc_frame_payload_get(fp, sizeof(*ap));
1277 memset(ap, 0, sizeof(*ap));
1279 ap->ba_high_seq_cnt = htons(0xffff);
1280 if (sp->ssb_stat & SSB_ST_RESP) {
1281 ap->ba_seq_id = sp->id;
1282 ap->ba_seq_id_val = FC_BA_SEQ_ID_VAL;
1283 ap->ba_high_seq_cnt = fh->fh_seq_cnt;
1284 ap->ba_low_seq_cnt = htons(sp->cnt);
1286 sp = fc_seq_start_next_locked(sp);
1287 spin_unlock_bh(&ep->ex_lock);
1288 fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS);
1289 fc_frame_free(rx_fp);
1293 fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID);
1295 fc_frame_free(rx_fp);
1299 * fc_seq_assign() - Assign exchange and sequence for incoming request
1300 * @lport: The local port that received the request
1301 * @fp: The request frame
1303 * On success, the sequence pointer will be returned and also in fr_seq(@fp).
1304 * A reference will be held on the exchange/sequence for the caller, which
1305 * must call fc_seq_release().
1307 static struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp)
1309 struct fc_exch_mgr_anchor *ema;
1311 WARN_ON(lport != fr_dev(fp));
1312 WARN_ON(fr_seq(fp));
1315 list_for_each_entry(ema, &lport->ema_list, ema_list)
1316 if ((!ema->match || ema->match(fp)) &&
1317 fc_seq_lookup_recip(lport, ema->mp, fp) == FC_RJT_NONE)
1323 * fc_seq_release() - Release the hold
1324 * @sp: The sequence.
1326 static void fc_seq_release(struct fc_seq *sp)
1328 fc_exch_release(fc_seq_exch(sp));
1332 * fc_exch_recv_req() - Handler for an incoming request
1333 * @lport: The local port that received the request
1334 * @mp: The EM that the exchange is on
1335 * @fp: The request frame
1337 * This is used when the other end is originating the exchange
1340 static void fc_exch_recv_req(struct fc_lport *lport, struct fc_exch_mgr *mp,
1341 struct fc_frame *fp)
1343 struct fc_frame_header *fh = fc_frame_header_get(fp);
1344 struct fc_seq *sp = NULL;
1345 struct fc_exch *ep = NULL;
1346 enum fc_pf_rjt_reason reject;
1348 /* We can have the wrong fc_lport at this point with NPIV, which is a
1349 * problem now that we know a new exchange needs to be allocated
1351 lport = fc_vport_id_lookup(lport, ntoh24(fh->fh_d_id));
1358 BUG_ON(fr_seq(fp)); /* XXX remove later */
1361 * If the RX_ID is 0xffff, don't allocate an exchange.
1362 * The upper-level protocol may request one later, if needed.
1364 if (fh->fh_rx_id == htons(FC_XID_UNKNOWN))
1365 return lport->tt.lport_recv(lport, fp);
1367 reject = fc_seq_lookup_recip(lport, mp, fp);
1368 if (reject == FC_RJT_NONE) {
1369 sp = fr_seq(fp); /* sequence will be held */
1370 ep = fc_seq_exch(sp);
1371 fc_seq_send_ack(sp, fp);
1372 ep->encaps = fr_encaps(fp);
1375 * Call the receive function.
1377 * The receive function may allocate a new sequence
1378 * over the old one, so we shouldn't change the
1379 * sequence after this.
1381 * The frame will be freed by the receive function.
1382 * If new exch resp handler is valid then call that
1386 ep->resp(sp, fp, ep->arg);
1388 lport->tt.lport_recv(lport, fp);
1389 fc_exch_release(ep); /* release from lookup */
1391 FC_LPORT_DBG(lport, "exch/seq lookup failed: reject %x\n",
1398 * fc_exch_recv_seq_resp() - Handler for an incoming response where the other
1399 * end is the originator of the sequence that is a
1400 * response to our initial exchange
1401 * @mp: The EM that the exchange is on
1402 * @fp: The response frame
1404 static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1406 struct fc_frame_header *fh = fc_frame_header_get(fp);
1411 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1415 ep = fc_exch_find(mp, ntohs(fh->fh_ox_id));
1417 atomic_inc(&mp->stats.xid_not_found);
1420 if (ep->esb_stat & ESB_ST_COMPLETE) {
1421 atomic_inc(&mp->stats.xid_not_found);
1424 if (ep->rxid == FC_XID_UNKNOWN)
1425 ep->rxid = ntohs(fh->fh_rx_id);
1426 if (ep->sid != 0 && ep->sid != ntoh24(fh->fh_d_id)) {
1427 atomic_inc(&mp->stats.xid_not_found);
1430 if (ep->did != ntoh24(fh->fh_s_id) &&
1431 ep->did != FC_FID_FLOGI) {
1432 atomic_inc(&mp->stats.xid_not_found);
1437 if (fc_sof_is_init(sof)) {
1438 sp->ssb_stat |= SSB_ST_RESP;
1439 sp->id = fh->fh_seq_id;
1440 } else if (sp->id != fh->fh_seq_id) {
1441 atomic_inc(&mp->stats.seq_not_found);
1445 f_ctl = ntoh24(fh->fh_f_ctl);
1447 if (f_ctl & FC_FC_SEQ_INIT)
1448 ep->esb_stat |= ESB_ST_SEQ_INIT;
1450 if (fc_sof_needs_ack(sof))
1451 fc_seq_send_ack(sp, fp);
1453 ex_resp_arg = ep->arg;
1455 if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T &&
1456 (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) ==
1457 (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) {
1458 spin_lock_bh(&ep->ex_lock);
1460 rc = fc_exch_done_locked(ep);
1461 WARN_ON(fc_seq_exch(sp) != ep);
1462 spin_unlock_bh(&ep->ex_lock);
1468 * Call the receive function.
1469 * The sequence is held (has a refcnt) for us,
1470 * but not for the receive function.
1472 * The receive function may allocate a new sequence
1473 * over the old one, so we shouldn't change the
1474 * sequence after this.
1476 * The frame will be freed by the receive function.
1477 * If new exch resp handler is valid then call that
1481 resp(sp, fp, ex_resp_arg);
1484 fc_exch_release(ep);
1487 fc_exch_release(ep);
1493 * fc_exch_recv_resp() - Handler for a sequence where other end is
1494 * responding to our sequence
1495 * @mp: The EM that the exchange is on
1496 * @fp: The response frame
1498 static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1502 sp = fc_seq_lookup_orig(mp, fp); /* doesn't hold sequence */
1505 atomic_inc(&mp->stats.xid_not_found);
1507 atomic_inc(&mp->stats.non_bls_resp);
1513 * fc_exch_abts_resp() - Handler for a response to an ABT
1514 * @ep: The exchange that the frame is on
1515 * @fp: The response frame
1517 * This response would be to an ABTS cancelling an exchange or sequence.
1518 * The response can be either BA_ACC or BA_RJT
1520 static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp)
1522 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1524 struct fc_frame_header *fh;
1525 struct fc_ba_acc *ap;
1529 int rc = 1, has_rec = 0;
1531 fh = fc_frame_header_get(fp);
1532 FC_EXCH_DBG(ep, "exch: BLS rctl %x - %s\n", fh->fh_r_ctl,
1533 fc_exch_rctl_name(fh->fh_r_ctl));
1535 if (cancel_delayed_work_sync(&ep->timeout_work))
1536 fc_exch_release(ep); /* release from pending timer hold */
1538 spin_lock_bh(&ep->ex_lock);
1539 switch (fh->fh_r_ctl) {
1540 case FC_RCTL_BA_ACC:
1541 ap = fc_frame_payload_get(fp, sizeof(*ap));
1546 * Decide whether to establish a Recovery Qualifier.
1547 * We do this if there is a non-empty SEQ_CNT range and
1548 * SEQ_ID is the same as the one we aborted.
1550 low = ntohs(ap->ba_low_seq_cnt);
1551 high = ntohs(ap->ba_high_seq_cnt);
1552 if ((ep->esb_stat & ESB_ST_REC_QUAL) == 0 &&
1553 (ap->ba_seq_id_val != FC_BA_SEQ_ID_VAL ||
1554 ap->ba_seq_id == ep->seq_id) && low != high) {
1555 ep->esb_stat |= ESB_ST_REC_QUAL;
1556 fc_exch_hold(ep); /* hold for recovery qualifier */
1560 case FC_RCTL_BA_RJT:
1567 ex_resp_arg = ep->arg;
1569 /* do we need to do some other checks here. Can we reuse more of
1570 * fc_exch_recv_seq_resp
1574 * do we want to check END_SEQ as well as LAST_SEQ here?
1576 if (ep->fh_type != FC_TYPE_FCP &&
1577 ntoh24(fh->fh_f_ctl) & FC_FC_LAST_SEQ)
1578 rc = fc_exch_done_locked(ep);
1579 spin_unlock_bh(&ep->ex_lock);
1584 resp(sp, fp, ex_resp_arg);
1589 fc_exch_timer_set(ep, ep->r_a_tov);
1594 * fc_exch_recv_bls() - Handler for a BLS sequence
1595 * @mp: The EM that the exchange is on
1596 * @fp: The request frame
1598 * The BLS frame is always a sequence initiated by the remote side.
1599 * We may be either the originator or recipient of the exchange.
1601 static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp)
1603 struct fc_frame_header *fh;
1607 fh = fc_frame_header_get(fp);
1608 f_ctl = ntoh24(fh->fh_f_ctl);
1611 ep = fc_exch_find(mp, (f_ctl & FC_FC_EX_CTX) ?
1612 ntohs(fh->fh_ox_id) : ntohs(fh->fh_rx_id));
1613 if (ep && (f_ctl & FC_FC_SEQ_INIT)) {
1614 spin_lock_bh(&ep->ex_lock);
1615 ep->esb_stat |= ESB_ST_SEQ_INIT;
1616 spin_unlock_bh(&ep->ex_lock);
1618 if (f_ctl & FC_FC_SEQ_CTX) {
1620 * A response to a sequence we initiated.
1621 * This should only be ACKs for class 2 or F.
1623 switch (fh->fh_r_ctl) {
1628 FC_EXCH_DBG(ep, "BLS rctl %x - %s received",
1630 fc_exch_rctl_name(fh->fh_r_ctl));
1635 switch (fh->fh_r_ctl) {
1636 case FC_RCTL_BA_RJT:
1637 case FC_RCTL_BA_ACC:
1639 fc_exch_abts_resp(ep, fp);
1643 case FC_RCTL_BA_ABTS:
1644 fc_exch_recv_abts(ep, fp);
1646 default: /* ignore junk */
1652 fc_exch_release(ep); /* release hold taken by fc_exch_find */
1656 * fc_seq_ls_acc() - Accept sequence with LS_ACC
1657 * @rx_fp: The received frame, not freed here.
1659 * If this fails due to allocation or transmit congestion, assume the
1660 * originator will repeat the sequence.
1662 static void fc_seq_ls_acc(struct fc_frame *rx_fp)
1664 struct fc_lport *lport;
1665 struct fc_els_ls_acc *acc;
1666 struct fc_frame *fp;
1668 lport = fr_dev(rx_fp);
1669 fp = fc_frame_alloc(lport, sizeof(*acc));
1672 acc = fc_frame_payload_get(fp, sizeof(*acc));
1673 memset(acc, 0, sizeof(*acc));
1674 acc->la_cmd = ELS_LS_ACC;
1675 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
1676 lport->tt.frame_send(lport, fp);
1680 * fc_seq_ls_rjt() - Reject a sequence with ELS LS_RJT
1681 * @rx_fp: The received frame, not freed here.
1682 * @reason: The reason the sequence is being rejected
1683 * @explan: The explanation for the rejection
1685 * If this fails due to allocation or transmit congestion, assume the
1686 * originator will repeat the sequence.
1688 static void fc_seq_ls_rjt(struct fc_frame *rx_fp, enum fc_els_rjt_reason reason,
1689 enum fc_els_rjt_explan explan)
1691 struct fc_lport *lport;
1692 struct fc_els_ls_rjt *rjt;
1693 struct fc_frame *fp;
1695 lport = fr_dev(rx_fp);
1696 fp = fc_frame_alloc(lport, sizeof(*rjt));
1699 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1700 memset(rjt, 0, sizeof(*rjt));
1701 rjt->er_cmd = ELS_LS_RJT;
1702 rjt->er_reason = reason;
1703 rjt->er_explan = explan;
1704 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
1705 lport->tt.frame_send(lport, fp);
1709 * fc_exch_reset() - Reset an exchange
1710 * @ep: The exchange to be reset
1712 static void fc_exch_reset(struct fc_exch *ep)
1715 void (*resp)(struct fc_seq *, struct fc_frame *, void *);
1719 spin_lock_bh(&ep->ex_lock);
1720 ep->state |= FC_EX_RST_CLEANUP;
1721 if (cancel_delayed_work(&ep->timeout_work))
1722 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */
1725 if (ep->esb_stat & ESB_ST_REC_QUAL)
1726 atomic_dec(&ep->ex_refcnt); /* drop hold for rec_qual */
1727 ep->esb_stat &= ~ESB_ST_REC_QUAL;
1730 rc = fc_exch_done_locked(ep);
1731 spin_unlock_bh(&ep->ex_lock);
1736 resp(sp, ERR_PTR(-FC_EX_CLOSED), arg);
1740 * fc_exch_pool_reset() - Reset a per cpu exchange pool
1741 * @lport: The local port that the exchange pool is on
1742 * @pool: The exchange pool to be reset
1743 * @sid: The source ID
1744 * @did: The destination ID
1746 * Resets a per cpu exches pool, releasing all of its sequences
1747 * and exchanges. If sid is non-zero then reset only exchanges
1748 * we sourced from the local port's FID. If did is non-zero then
1749 * only reset exchanges destined for the local port's FID.
1751 static void fc_exch_pool_reset(struct fc_lport *lport,
1752 struct fc_exch_pool *pool,
1756 struct fc_exch *next;
1758 spin_lock_bh(&pool->lock);
1760 list_for_each_entry_safe(ep, next, &pool->ex_list, ex_list) {
1761 if ((lport == ep->lp) &&
1762 (sid == 0 || sid == ep->sid) &&
1763 (did == 0 || did == ep->did)) {
1765 spin_unlock_bh(&pool->lock);
1769 fc_exch_release(ep);
1770 spin_lock_bh(&pool->lock);
1773 * must restart loop incase while lock
1774 * was down multiple eps were released.
1779 spin_unlock_bh(&pool->lock);
1783 * fc_exch_mgr_reset() - Reset all EMs of a local port
1784 * @lport: The local port whose EMs are to be reset
1785 * @sid: The source ID
1786 * @did: The destination ID
1788 * Reset all EMs associated with a given local port. Release all
1789 * sequences and exchanges. If sid is non-zero then reset only the
1790 * exchanges sent from the local port's FID. If did is non-zero then
1791 * reset only exchanges destined for the local port's FID.
1793 void fc_exch_mgr_reset(struct fc_lport *lport, u32 sid, u32 did)
1795 struct fc_exch_mgr_anchor *ema;
1798 list_for_each_entry(ema, &lport->ema_list, ema_list) {
1799 for_each_possible_cpu(cpu)
1800 fc_exch_pool_reset(lport,
1801 per_cpu_ptr(ema->mp->pool, cpu),
1805 EXPORT_SYMBOL(fc_exch_mgr_reset);
1808 * fc_exch_lookup() - find an exchange
1809 * @lport: The local port
1810 * @xid: The exchange ID
1812 * Returns exchange pointer with hold for caller, or NULL if not found.
1814 static struct fc_exch *fc_exch_lookup(struct fc_lport *lport, u32 xid)
1816 struct fc_exch_mgr_anchor *ema;
1818 list_for_each_entry(ema, &lport->ema_list, ema_list)
1819 if (ema->mp->min_xid <= xid && xid <= ema->mp->max_xid)
1820 return fc_exch_find(ema->mp, xid);
1825 * fc_exch_els_rec() - Handler for ELS REC (Read Exchange Concise) requests
1826 * @rfp: The REC frame, not freed here.
1828 * Note that the requesting port may be different than the S_ID in the request.
1830 static void fc_exch_els_rec(struct fc_frame *rfp)
1832 struct fc_lport *lport;
1833 struct fc_frame *fp;
1835 struct fc_els_rec *rp;
1836 struct fc_els_rec_acc *acc;
1837 enum fc_els_rjt_reason reason = ELS_RJT_LOGIC;
1838 enum fc_els_rjt_explan explan;
1843 lport = fr_dev(rfp);
1844 rp = fc_frame_payload_get(rfp, sizeof(*rp));
1845 explan = ELS_EXPL_INV_LEN;
1848 sid = ntoh24(rp->rec_s_id);
1849 rxid = ntohs(rp->rec_rx_id);
1850 oxid = ntohs(rp->rec_ox_id);
1852 ep = fc_exch_lookup(lport,
1853 sid == fc_host_port_id(lport->host) ? oxid : rxid);
1854 explan = ELS_EXPL_OXID_RXID;
1857 if (ep->oid != sid || oxid != ep->oxid)
1859 if (rxid != FC_XID_UNKNOWN && rxid != ep->rxid)
1861 fp = fc_frame_alloc(lport, sizeof(*acc));
1865 acc = fc_frame_payload_get(fp, sizeof(*acc));
1866 memset(acc, 0, sizeof(*acc));
1867 acc->reca_cmd = ELS_LS_ACC;
1868 acc->reca_ox_id = rp->rec_ox_id;
1869 memcpy(acc->reca_ofid, rp->rec_s_id, 3);
1870 acc->reca_rx_id = htons(ep->rxid);
1871 if (ep->sid == ep->oid)
1872 hton24(acc->reca_rfid, ep->did);
1874 hton24(acc->reca_rfid, ep->sid);
1875 acc->reca_fc4value = htonl(ep->seq.rec_data);
1876 acc->reca_e_stat = htonl(ep->esb_stat & (ESB_ST_RESP |
1879 fc_fill_reply_hdr(fp, rfp, FC_RCTL_ELS_REP, 0);
1880 lport->tt.frame_send(lport, fp);
1882 fc_exch_release(ep);
1886 fc_exch_release(ep);
1888 fc_seq_ls_rjt(rfp, reason, explan);
1892 * fc_exch_rrq_resp() - Handler for RRQ responses
1893 * @sp: The sequence that the RRQ is on
1894 * @fp: The RRQ frame
1895 * @arg: The exchange that the RRQ is on
1897 * TODO: fix error handler.
1899 static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg)
1901 struct fc_exch *aborted_ep = arg;
1905 int err = PTR_ERR(fp);
1907 if (err == -FC_EX_CLOSED || err == -FC_EX_TIMEOUT)
1909 FC_EXCH_DBG(aborted_ep, "Cannot process RRQ, "
1910 "frame error %d\n", err);
1914 op = fc_frame_payload_op(fp);
1919 FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ");
1924 FC_EXCH_DBG(aborted_ep, "unexpected response op %x "
1930 fc_exch_done(&aborted_ep->seq);
1931 /* drop hold for rec qual */
1932 fc_exch_release(aborted_ep);
1937 * fc_exch_seq_send() - Send a frame using a new exchange and sequence
1938 * @lport: The local port to send the frame on
1939 * @fp: The frame to be sent
1940 * @resp: The response handler for this request
1941 * @destructor: The destructor for the exchange
1942 * @arg: The argument to be passed to the response handler
1943 * @timer_msec: The timeout period for the exchange
1945 * The frame pointer with some of the header's fields must be
1946 * filled before calling this routine, those fields are:
1953 * - parameter or relative offset
1955 static struct fc_seq *fc_exch_seq_send(struct fc_lport *lport,
1956 struct fc_frame *fp,
1957 void (*resp)(struct fc_seq *,
1958 struct fc_frame *fp,
1960 void (*destructor)(struct fc_seq *,
1962 void *arg, u32 timer_msec)
1965 struct fc_seq *sp = NULL;
1966 struct fc_frame_header *fh;
1969 ep = fc_exch_alloc(lport, fp);
1974 ep->esb_stat |= ESB_ST_SEQ_INIT;
1975 fh = fc_frame_header_get(fp);
1976 fc_exch_set_addr(ep, ntoh24(fh->fh_s_id), ntoh24(fh->fh_d_id));
1978 ep->destructor = destructor;
1980 ep->r_a_tov = FC_DEF_R_A_TOV;
1984 ep->fh_type = fh->fh_type; /* save for possbile timeout handling */
1985 ep->f_ctl = ntoh24(fh->fh_f_ctl);
1986 fc_exch_setup_hdr(ep, fp, ep->f_ctl);
1989 if (ep->xid <= lport->lro_xid && fh->fh_r_ctl == FC_RCTL_DD_UNSOL_CMD)
1990 fc_fcp_ddp_setup(fr_fsp(fp), ep->xid);
1992 if (unlikely(lport->tt.frame_send(lport, fp)))
1996 fc_exch_timer_set_locked(ep, timer_msec);
1997 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not first seq */
1999 if (ep->f_ctl & FC_FC_SEQ_INIT)
2000 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
2001 spin_unlock_bh(&ep->ex_lock);
2004 fc_fcp_ddp_done(fr_fsp(fp));
2005 rc = fc_exch_done_locked(ep);
2006 spin_unlock_bh(&ep->ex_lock);
2013 * fc_exch_rrq() - Send an ELS RRQ (Reinstate Recovery Qualifier) command
2014 * @ep: The exchange to send the RRQ on
2016 * This tells the remote port to stop blocking the use of
2017 * the exchange and the seq_cnt range.
2019 static void fc_exch_rrq(struct fc_exch *ep)
2021 struct fc_lport *lport;
2022 struct fc_els_rrq *rrq;
2023 struct fc_frame *fp;
2028 fp = fc_frame_alloc(lport, sizeof(*rrq));
2032 rrq = fc_frame_payload_get(fp, sizeof(*rrq));
2033 memset(rrq, 0, sizeof(*rrq));
2034 rrq->rrq_cmd = ELS_RRQ;
2035 hton24(rrq->rrq_s_id, ep->sid);
2036 rrq->rrq_ox_id = htons(ep->oxid);
2037 rrq->rrq_rx_id = htons(ep->rxid);
2040 if (ep->esb_stat & ESB_ST_RESP)
2043 fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, did,
2044 lport->port_id, FC_TYPE_ELS,
2045 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
2047 if (fc_exch_seq_send(lport, fp, fc_exch_rrq_resp, NULL, ep,
2052 spin_lock_bh(&ep->ex_lock);
2053 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) {
2054 spin_unlock_bh(&ep->ex_lock);
2055 /* drop hold for rec qual */
2056 fc_exch_release(ep);
2059 ep->esb_stat |= ESB_ST_REC_QUAL;
2060 fc_exch_timer_set_locked(ep, ep->r_a_tov);
2061 spin_unlock_bh(&ep->ex_lock);
2065 * fc_exch_els_rrq() - Handler for ELS RRQ (Reset Recovery Qualifier) requests
2066 * @fp: The RRQ frame, not freed here.
2068 static void fc_exch_els_rrq(struct fc_frame *fp)
2070 struct fc_lport *lport;
2071 struct fc_exch *ep = NULL; /* request or subject exchange */
2072 struct fc_els_rrq *rp;
2075 enum fc_els_rjt_explan explan;
2078 rp = fc_frame_payload_get(fp, sizeof(*rp));
2079 explan = ELS_EXPL_INV_LEN;
2084 * lookup subject exchange.
2086 sid = ntoh24(rp->rrq_s_id); /* subject source */
2087 xid = fc_host_port_id(lport->host) == sid ?
2088 ntohs(rp->rrq_ox_id) : ntohs(rp->rrq_rx_id);
2089 ep = fc_exch_lookup(lport, xid);
2090 explan = ELS_EXPL_OXID_RXID;
2093 spin_lock_bh(&ep->ex_lock);
2094 if (ep->oxid != ntohs(rp->rrq_ox_id))
2096 if (ep->rxid != ntohs(rp->rrq_rx_id) &&
2097 ep->rxid != FC_XID_UNKNOWN)
2099 explan = ELS_EXPL_SID;
2104 * Clear Recovery Qualifier state, and cancel timer if complete.
2106 if (ep->esb_stat & ESB_ST_REC_QUAL) {
2107 ep->esb_stat &= ~ESB_ST_REC_QUAL;
2108 atomic_dec(&ep->ex_refcnt); /* drop hold for rec qual */
2110 if (ep->esb_stat & ESB_ST_COMPLETE) {
2111 if (cancel_delayed_work(&ep->timeout_work))
2112 atomic_dec(&ep->ex_refcnt); /* drop timer hold */
2115 spin_unlock_bh(&ep->ex_lock);
2124 spin_unlock_bh(&ep->ex_lock);
2126 fc_seq_ls_rjt(fp, ELS_RJT_LOGIC, explan);
2129 fc_exch_release(ep); /* drop hold from fc_exch_find */
2133 * fc_exch_mgr_add() - Add an exchange manager to a local port's list of EMs
2134 * @lport: The local port to add the exchange manager to
2135 * @mp: The exchange manager to be added to the local port
2136 * @match: The match routine that indicates when this EM should be used
2138 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport,
2139 struct fc_exch_mgr *mp,
2140 bool (*match)(struct fc_frame *))
2142 struct fc_exch_mgr_anchor *ema;
2144 ema = kmalloc(sizeof(*ema), GFP_ATOMIC);
2150 /* add EM anchor to EM anchors list */
2151 list_add_tail(&ema->ema_list, &lport->ema_list);
2152 kref_get(&mp->kref);
2155 EXPORT_SYMBOL(fc_exch_mgr_add);
2158 * fc_exch_mgr_destroy() - Destroy an exchange manager
2159 * @kref: The reference to the EM to be destroyed
2161 static void fc_exch_mgr_destroy(struct kref *kref)
2163 struct fc_exch_mgr *mp = container_of(kref, struct fc_exch_mgr, kref);
2165 mempool_destroy(mp->ep_pool);
2166 free_percpu(mp->pool);
2171 * fc_exch_mgr_del() - Delete an EM from a local port's list
2172 * @ema: The exchange manager anchor identifying the EM to be deleted
2174 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema)
2176 /* remove EM anchor from EM anchors list */
2177 list_del(&ema->ema_list);
2178 kref_put(&ema->mp->kref, fc_exch_mgr_destroy);
2181 EXPORT_SYMBOL(fc_exch_mgr_del);
2184 * fc_exch_mgr_list_clone() - Share all exchange manager objects
2185 * @src: Source lport to clone exchange managers from
2186 * @dst: New lport that takes references to all the exchange managers
2188 int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst)
2190 struct fc_exch_mgr_anchor *ema, *tmp;
2192 list_for_each_entry(ema, &src->ema_list, ema_list) {
2193 if (!fc_exch_mgr_add(dst, ema->mp, ema->match))
2198 list_for_each_entry_safe(ema, tmp, &dst->ema_list, ema_list)
2199 fc_exch_mgr_del(ema);
2202 EXPORT_SYMBOL(fc_exch_mgr_list_clone);
2205 * fc_exch_mgr_alloc() - Allocate an exchange manager
2206 * @lport: The local port that the new EM will be associated with
2207 * @class: The default FC class for new exchanges
2208 * @min_xid: The minimum XID for exchanges from the new EM
2209 * @max_xid: The maximum XID for exchanges from the new EM
2210 * @match: The match routine for the new EM
2212 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lport,
2213 enum fc_class class,
2214 u16 min_xid, u16 max_xid,
2215 bool (*match)(struct fc_frame *))
2217 struct fc_exch_mgr *mp;
2218 u16 pool_exch_range;
2221 struct fc_exch_pool *pool;
2223 if (max_xid <= min_xid || max_xid == FC_XID_UNKNOWN ||
2224 (min_xid & fc_cpu_mask) != 0) {
2225 FC_LPORT_DBG(lport, "Invalid min_xid 0x:%x and max_xid 0x:%x\n",
2231 * allocate memory for EM
2233 mp = kzalloc(sizeof(struct fc_exch_mgr), GFP_ATOMIC);
2238 /* adjust em exch xid range for offload */
2239 mp->min_xid = min_xid;
2240 mp->max_xid = max_xid;
2242 mp->ep_pool = mempool_create_slab_pool(2, fc_em_cachep);
2247 * Setup per cpu exch pool with entire exchange id range equally
2248 * divided across all cpus. The exch pointers array memory is
2249 * allocated for exch range per pool.
2251 pool_exch_range = (mp->max_xid - mp->min_xid + 1) / (fc_cpu_mask + 1);
2252 mp->pool_max_index = pool_exch_range - 1;
2255 * Allocate and initialize per cpu exch pool
2257 pool_size = sizeof(*pool) + pool_exch_range * sizeof(struct fc_exch *);
2258 mp->pool = __alloc_percpu(pool_size, __alignof__(struct fc_exch_pool));
2261 for_each_possible_cpu(cpu) {
2262 pool = per_cpu_ptr(mp->pool, cpu);
2263 pool->left = FC_XID_UNKNOWN;
2264 pool->right = FC_XID_UNKNOWN;
2265 spin_lock_init(&pool->lock);
2266 INIT_LIST_HEAD(&pool->ex_list);
2269 kref_init(&mp->kref);
2270 if (!fc_exch_mgr_add(lport, mp, match)) {
2271 free_percpu(mp->pool);
2276 * Above kref_init() sets mp->kref to 1 and then
2277 * call to fc_exch_mgr_add incremented mp->kref again,
2278 * so adjust that extra increment.
2280 kref_put(&mp->kref, fc_exch_mgr_destroy);
2284 mempool_destroy(mp->ep_pool);
2289 EXPORT_SYMBOL(fc_exch_mgr_alloc);
2292 * fc_exch_mgr_free() - Free all exchange managers on a local port
2293 * @lport: The local port whose EMs are to be freed
2295 void fc_exch_mgr_free(struct fc_lport *lport)
2297 struct fc_exch_mgr_anchor *ema, *next;
2299 flush_workqueue(fc_exch_workqueue);
2300 list_for_each_entry_safe(ema, next, &lport->ema_list, ema_list)
2301 fc_exch_mgr_del(ema);
2303 EXPORT_SYMBOL(fc_exch_mgr_free);
2306 * fc_find_ema() - Lookup and return appropriate Exchange Manager Anchor depending
2309 * @lport: The local port the frame was received on
2310 * @fh: The received frame header
2312 static struct fc_exch_mgr_anchor *fc_find_ema(u32 f_ctl,
2313 struct fc_lport *lport,
2314 struct fc_frame_header *fh)
2316 struct fc_exch_mgr_anchor *ema;
2319 if (f_ctl & FC_FC_EX_CTX)
2320 xid = ntohs(fh->fh_ox_id);
2322 xid = ntohs(fh->fh_rx_id);
2323 if (xid == FC_XID_UNKNOWN)
2324 return list_entry(lport->ema_list.prev,
2325 typeof(*ema), ema_list);
2328 list_for_each_entry(ema, &lport->ema_list, ema_list) {
2329 if ((xid >= ema->mp->min_xid) &&
2330 (xid <= ema->mp->max_xid))
2336 * fc_exch_recv() - Handler for received frames
2337 * @lport: The local port the frame was received on
2338 * @fp: The received frame
2340 void fc_exch_recv(struct fc_lport *lport, struct fc_frame *fp)
2342 struct fc_frame_header *fh = fc_frame_header_get(fp);
2343 struct fc_exch_mgr_anchor *ema;
2347 if (!lport || lport->state == LPORT_ST_DISABLED) {
2348 FC_LPORT_DBG(lport, "Receiving frames for an lport that "
2349 "has not been initialized correctly\n");
2354 f_ctl = ntoh24(fh->fh_f_ctl);
2355 ema = fc_find_ema(f_ctl, lport, fh);
2357 FC_LPORT_DBG(lport, "Unable to find Exchange Manager Anchor,"
2358 "fc_ctl <0x%x>, xid <0x%x>\n",
2360 (f_ctl & FC_FC_EX_CTX) ?
2361 ntohs(fh->fh_ox_id) :
2362 ntohs(fh->fh_rx_id));
2368 * If frame is marked invalid, just drop it.
2370 switch (fr_eof(fp)) {
2372 if (f_ctl & FC_FC_END_SEQ)
2373 skb_trim(fp_skb(fp), fr_len(fp) - FC_FC_FILL(f_ctl));
2376 if (fh->fh_type == FC_TYPE_BLS)
2377 fc_exch_recv_bls(ema->mp, fp);
2378 else if ((f_ctl & (FC_FC_EX_CTX | FC_FC_SEQ_CTX)) ==
2380 fc_exch_recv_seq_resp(ema->mp, fp);
2381 else if (f_ctl & FC_FC_SEQ_CTX)
2382 fc_exch_recv_resp(ema->mp, fp);
2383 else /* no EX_CTX and no SEQ_CTX */
2384 fc_exch_recv_req(lport, ema->mp, fp);
2387 FC_LPORT_DBG(lport, "dropping invalid frame (eof %x)",
2392 EXPORT_SYMBOL(fc_exch_recv);
2395 * fc_exch_init() - Initialize the exchange layer for a local port
2396 * @lport: The local port to initialize the exchange layer for
2398 int fc_exch_init(struct fc_lport *lport)
2400 if (!lport->tt.seq_start_next)
2401 lport->tt.seq_start_next = fc_seq_start_next;
2403 if (!lport->tt.seq_set_resp)
2404 lport->tt.seq_set_resp = fc_seq_set_resp;
2406 if (!lport->tt.exch_seq_send)
2407 lport->tt.exch_seq_send = fc_exch_seq_send;
2409 if (!lport->tt.seq_send)
2410 lport->tt.seq_send = fc_seq_send;
2412 if (!lport->tt.seq_els_rsp_send)
2413 lport->tt.seq_els_rsp_send = fc_seq_els_rsp_send;
2415 if (!lport->tt.exch_done)
2416 lport->tt.exch_done = fc_exch_done;
2418 if (!lport->tt.exch_mgr_reset)
2419 lport->tt.exch_mgr_reset = fc_exch_mgr_reset;
2421 if (!lport->tt.seq_exch_abort)
2422 lport->tt.seq_exch_abort = fc_seq_exch_abort;
2424 if (!lport->tt.seq_assign)
2425 lport->tt.seq_assign = fc_seq_assign;
2427 if (!lport->tt.seq_release)
2428 lport->tt.seq_release = fc_seq_release;
2432 EXPORT_SYMBOL(fc_exch_init);
2435 * fc_setup_exch_mgr() - Setup an exchange manager
2437 int fc_setup_exch_mgr(void)
2439 fc_em_cachep = kmem_cache_create("libfc_em", sizeof(struct fc_exch),
2440 0, SLAB_HWCACHE_ALIGN, NULL);
2445 * Initialize fc_cpu_mask and fc_cpu_order. The
2446 * fc_cpu_mask is set for nr_cpu_ids rounded up
2447 * to order of 2's * power and order is stored
2448 * in fc_cpu_order as this is later required in
2449 * mapping between an exch id and exch array index
2450 * in per cpu exch pool.
2452 * This round up is required to align fc_cpu_mask
2453 * to exchange id's lower bits such that all incoming
2454 * frames of an exchange gets delivered to the same
2455 * cpu on which exchange originated by simple bitwise
2456 * AND operation between fc_cpu_mask and exchange id.
2460 while (fc_cpu_mask < nr_cpu_ids) {
2466 fc_exch_workqueue = create_singlethread_workqueue("fc_exch_workqueue");
2467 if (!fc_exch_workqueue)
2473 * fc_destroy_exch_mgr() - Destroy an exchange manager
2475 void fc_destroy_exch_mgr(void)
2477 destroy_workqueue(fc_exch_workqueue);
2478 kmem_cache_destroy(fc_em_cachep);