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 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 struct list_head ex_list;
75 * struct fc_exch_mgr - The Exchange Manager (EM).
76 * @class: Default class for new sequences
77 * @kref: Reference counter
78 * @min_xid: Minimum exchange ID
79 * @max_xid: Maximum exchange ID
80 * @ep_pool: Reserved exchange pointers
81 * @pool_max_index: Max exch array index in exch pool
82 * @pool: Per cpu exch pool
83 * @stats: Statistics structure
85 * This structure is the center for creating exchanges and sequences.
86 * It manages the allocation of exchange IDs.
95 struct fc_exch_pool *pool;
98 * currently exchange mgr stats are updated but not used.
99 * either stats can be expose via sysfs or remove them
100 * all together if not used XXX
103 atomic_t no_free_exch;
104 atomic_t no_free_exch_xid;
105 atomic_t xid_not_found;
107 atomic_t seq_not_found;
108 atomic_t non_bls_resp;
111 #define fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
114 * struct fc_exch_mgr_anchor - primary structure for list of EMs
115 * @ema_list: Exchange Manager Anchor list
116 * @mp: Exchange Manager associated with this anchor
117 * @match: Routine to determine if this anchor's EM should be used
119 * When walking the list of anchors the match routine will be called
120 * for each anchor to determine if that EM should be used. The last
121 * anchor in the list will always match to handle any exchanges not
122 * handled by other EMs. The non-default EMs would be added to the
123 * anchor list by HW that provides FCoE offloads.
125 struct fc_exch_mgr_anchor {
126 struct list_head ema_list;
127 struct fc_exch_mgr *mp;
128 bool (*match)(struct fc_frame *);
131 static void fc_exch_rrq(struct fc_exch *);
132 static void fc_seq_ls_acc(struct fc_frame *);
133 static void fc_seq_ls_rjt(struct fc_frame *, enum fc_els_rjt_reason,
134 enum fc_els_rjt_explan);
135 static void fc_exch_els_rec(struct fc_frame *);
136 static void fc_exch_els_rrq(struct fc_frame *);
139 * Internal implementation notes.
141 * The exchange manager is one by default in libfc but LLD may choose
142 * to have one per CPU. The sequence manager is one per exchange manager
143 * and currently never separated.
145 * Section 9.8 in FC-FS-2 specifies: "The SEQ_ID is a one-byte field
146 * assigned by the Sequence Initiator that shall be unique for a specific
147 * D_ID and S_ID pair while the Sequence is open." Note that it isn't
148 * qualified by exchange ID, which one might think it would be.
149 * In practice this limits the number of open sequences and exchanges to 256
150 * per session. For most targets we could treat this limit as per exchange.
152 * The exchange and its sequence are freed when the last sequence is received.
153 * It's possible for the remote port to leave an exchange open without
154 * sending any sequences.
156 * Notes on reference counts:
158 * Exchanges are reference counted and exchange gets freed when the reference
159 * count becomes zero.
162 * Sequences are timed out for E_D_TOV and R_A_TOV.
164 * Sequence event handling:
166 * The following events may occur on initiator sequences:
169 * For now, the whole thing is sent.
171 * This applies only to class F.
172 * The sequence is marked complete.
174 * The upper layer calls fc_exch_done() when done
175 * with exchange and sequence tuple.
176 * RX-inferred completion.
177 * When we receive the next sequence on the same exchange, we can
178 * retire the previous sequence ID. (XXX not implemented).
180 * R_A_TOV frees the sequence ID. If we're waiting for ACK,
181 * E_D_TOV causes abort and calls upper layer response handler
182 * with FC_EX_TIMEOUT error.
188 * The following events may occur on recipient sequences:
191 * Allocate sequence for first frame received.
192 * Hold during receive handler.
193 * Release when final frame received.
194 * Keep status of last N of these for the ELS RES command. XXX TBD.
196 * Deallocate sequence
200 * For now, we neglect conditions where only part of a sequence was
201 * received or transmitted, or where out-of-order receipt is detected.
207 * The EM code run in a per-CPU worker thread.
209 * To protect against concurrency between a worker thread code and timers,
210 * sequence allocation and deallocation must be locked.
211 * - exchange refcnt can be done atomicly without locks.
212 * - sequence allocation must be locked by exch lock.
213 * - If the EM pool lock and ex_lock must be taken at the same time, then the
214 * EM pool lock must be taken before the ex_lock.
218 * opcode names for debugging.
220 static char *fc_exch_rctl_names[] = FC_RCTL_NAMES_INIT;
223 * fc_exch_name_lookup() - Lookup name by opcode
224 * @op: Opcode to be looked up
225 * @table: Opcode/name table
226 * @max_index: Index not to be exceeded
228 * This routine is used to determine a human-readable string identifying
231 static inline const char *fc_exch_name_lookup(unsigned int op, char **table,
232 unsigned int max_index)
234 const char *name = NULL;
244 * fc_exch_rctl_name() - Wrapper routine for fc_exch_name_lookup()
245 * @op: The opcode to be looked up
247 static const char *fc_exch_rctl_name(unsigned int op)
249 return fc_exch_name_lookup(op, fc_exch_rctl_names,
250 ARRAY_SIZE(fc_exch_rctl_names));
254 * fc_exch_hold() - Increment an exchange's reference count
255 * @ep: Echange to be held
257 static inline void fc_exch_hold(struct fc_exch *ep)
259 atomic_inc(&ep->ex_refcnt);
263 * fc_exch_setup_hdr() - Initialize a FC header by initializing some fields
264 * and determine SOF and EOF.
265 * @ep: The exchange to that will use the header
266 * @fp: The frame whose header is to be modified
267 * @f_ctl: F_CTL bits that will be used for the frame header
269 * The fields initialized by this routine are: fh_ox_id, fh_rx_id,
270 * fh_seq_id, fh_seq_cnt and the SOF and EOF.
272 static void fc_exch_setup_hdr(struct fc_exch *ep, struct fc_frame *fp,
275 struct fc_frame_header *fh = fc_frame_header_get(fp);
278 fr_sof(fp) = ep->class;
280 fr_sof(fp) = fc_sof_normal(ep->class);
282 if (f_ctl & FC_FC_END_SEQ) {
283 fr_eof(fp) = FC_EOF_T;
284 if (fc_sof_needs_ack(ep->class))
285 fr_eof(fp) = FC_EOF_N;
288 * The number of fill bytes to make the length a 4-byte
289 * multiple is the low order 2-bits of the f_ctl.
290 * The fill itself will have been cleared by the frame
292 * After this, the length will be even, as expected by
295 fill = fr_len(fp) & 3;
298 /* TODO, this may be a problem with fragmented skb */
299 skb_put(fp_skb(fp), fill);
300 hton24(fh->fh_f_ctl, f_ctl | fill);
303 WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */
304 fr_eof(fp) = FC_EOF_N;
308 * Initialize remainig fh fields
309 * from fc_fill_fc_hdr
311 fh->fh_ox_id = htons(ep->oxid);
312 fh->fh_rx_id = htons(ep->rxid);
313 fh->fh_seq_id = ep->seq.id;
314 fh->fh_seq_cnt = htons(ep->seq.cnt);
318 * fc_exch_release() - Decrement an exchange's reference count
319 * @ep: Exchange to be released
321 * If the reference count reaches zero and the exchange is complete,
324 static void fc_exch_release(struct fc_exch *ep)
326 struct fc_exch_mgr *mp;
328 if (atomic_dec_and_test(&ep->ex_refcnt)) {
331 ep->destructor(&ep->seq, ep->arg);
332 WARN_ON(!(ep->esb_stat & ESB_ST_COMPLETE));
333 mempool_free(ep, mp->ep_pool);
338 * fc_exch_done_locked() - Complete an exchange with the exchange lock held
339 * @ep: The exchange that is complete
341 static int fc_exch_done_locked(struct fc_exch *ep)
346 * We must check for completion in case there are two threads
347 * tyring to complete this. But the rrq code will reuse the
348 * ep, and in that case we only clear the resp and set it as
349 * complete, so it can be reused by the timer to send the rrq.
352 if (ep->state & FC_EX_DONE)
354 ep->esb_stat |= ESB_ST_COMPLETE;
356 if (!(ep->esb_stat & ESB_ST_REC_QUAL)) {
357 ep->state |= FC_EX_DONE;
358 if (cancel_delayed_work(&ep->timeout_work))
359 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */
366 * fc_exch_ptr_get() - Return an exchange from an exchange pool
367 * @pool: Exchange Pool to get an exchange from
368 * @index: Index of the exchange within the pool
370 * Use the index to get an exchange from within an exchange pool. exches
371 * will point to an array of exchange pointers. The index will select
372 * the exchange within the array.
374 static inline struct fc_exch *fc_exch_ptr_get(struct fc_exch_pool *pool,
377 struct fc_exch **exches = (struct fc_exch **)(pool + 1);
378 return exches[index];
382 * fc_exch_ptr_set() - Assign an exchange to a slot in an exchange pool
383 * @pool: The pool to assign the exchange to
384 * @index: The index in the pool where the exchange will be assigned
385 * @ep: The exchange to assign to the pool
387 static inline void fc_exch_ptr_set(struct fc_exch_pool *pool, u16 index,
390 ((struct fc_exch **)(pool + 1))[index] = ep;
394 * fc_exch_delete() - Delete an exchange
395 * @ep: The exchange to be deleted
397 static void fc_exch_delete(struct fc_exch *ep)
399 struct fc_exch_pool *pool;
402 spin_lock_bh(&pool->lock);
403 WARN_ON(pool->total_exches <= 0);
404 pool->total_exches--;
405 fc_exch_ptr_set(pool, (ep->xid - ep->em->min_xid) >> fc_cpu_order,
407 list_del(&ep->ex_list);
408 spin_unlock_bh(&pool->lock);
409 fc_exch_release(ep); /* drop hold for exch in mp */
413 * fc_exch_timer_set_locked() - Start a timer for an exchange w/ the
414 * the exchange lock held
415 * @ep: The exchange whose timer will start
416 * @timer_msec: The timeout period
418 * Used for upper level protocols to time out the exchange.
419 * The timer is cancelled when it fires or when the exchange completes.
421 static inline void fc_exch_timer_set_locked(struct fc_exch *ep,
422 unsigned int timer_msec)
424 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
427 FC_EXCH_DBG(ep, "Exchange timer armed\n");
429 if (queue_delayed_work(fc_exch_workqueue, &ep->timeout_work,
430 msecs_to_jiffies(timer_msec)))
431 fc_exch_hold(ep); /* hold for timer */
435 * fc_exch_timer_set() - Lock the exchange and set the timer
436 * @ep: The exchange whose timer will start
437 * @timer_msec: The timeout period
439 static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec)
441 spin_lock_bh(&ep->ex_lock);
442 fc_exch_timer_set_locked(ep, timer_msec);
443 spin_unlock_bh(&ep->ex_lock);
447 * fc_seq_send() - Send a frame using existing sequence/exchange pair
448 * @lport: The local port that the exchange will be sent on
449 * @sp: The sequence to be sent
450 * @fp: The frame to be sent on the exchange
452 static int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp,
456 struct fc_frame_header *fh = fc_frame_header_get(fp);
460 ep = fc_seq_exch(sp);
461 WARN_ON((ep->esb_stat & ESB_ST_SEQ_INIT) != ESB_ST_SEQ_INIT);
463 f_ctl = ntoh24(fh->fh_f_ctl);
464 fc_exch_setup_hdr(ep, fp, f_ctl);
465 fr_encaps(fp) = ep->encaps;
468 * update sequence count if this frame is carrying
469 * multiple FC frames when sequence offload is enabled
472 if (fr_max_payload(fp))
473 sp->cnt += DIV_ROUND_UP((fr_len(fp) - sizeof(*fh)),
481 error = lport->tt.frame_send(lport, fp);
484 * Update the exchange and sequence flags,
485 * assuming all frames for the sequence have been sent.
486 * We can only be called to send once for each sequence.
488 spin_lock_bh(&ep->ex_lock);
489 ep->f_ctl = f_ctl & ~FC_FC_FIRST_SEQ; /* not first seq */
490 if (f_ctl & FC_FC_SEQ_INIT)
491 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
492 spin_unlock_bh(&ep->ex_lock);
497 * fc_seq_alloc() - Allocate a sequence for a given exchange
498 * @ep: The exchange to allocate a new sequence for
499 * @seq_id: The sequence ID to be used
501 * We don't support multiple originated sequences on the same exchange.
502 * By implication, any previously originated sequence on this exchange
503 * is complete, and we reallocate the same sequence.
505 static struct fc_seq *fc_seq_alloc(struct fc_exch *ep, u8 seq_id)
517 * fc_seq_start_next_locked() - Allocate a new sequence on the same
518 * exchange as the supplied sequence
519 * @sp: The sequence/exchange to get a new sequence for
521 static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp)
523 struct fc_exch *ep = fc_seq_exch(sp);
525 sp = fc_seq_alloc(ep, ep->seq_id++);
526 FC_EXCH_DBG(ep, "f_ctl %6x seq %2x\n",
532 * fc_seq_start_next() - Lock the exchange and get a new sequence
533 * for a given sequence/exchange pair
534 * @sp: The sequence/exchange to get a new exchange for
536 static struct fc_seq *fc_seq_start_next(struct fc_seq *sp)
538 struct fc_exch *ep = fc_seq_exch(sp);
540 spin_lock_bh(&ep->ex_lock);
541 sp = fc_seq_start_next_locked(sp);
542 spin_unlock_bh(&ep->ex_lock);
548 * fc_seq_exch_abort() - Abort an exchange and sequence
549 * @req_sp: The sequence to be aborted
550 * @timer_msec: The period of time to wait before aborting
552 * Generally called because of a timeout or an abort from the upper layer.
554 static int fc_seq_exch_abort(const struct fc_seq *req_sp,
555 unsigned int timer_msec)
562 ep = fc_seq_exch(req_sp);
564 spin_lock_bh(&ep->ex_lock);
565 if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL) ||
566 ep->state & (FC_EX_DONE | FC_EX_RST_CLEANUP)) {
567 spin_unlock_bh(&ep->ex_lock);
572 * Send the abort on a new sequence if possible.
574 sp = fc_seq_start_next_locked(&ep->seq);
576 spin_unlock_bh(&ep->ex_lock);
580 ep->esb_stat |= ESB_ST_SEQ_INIT | ESB_ST_ABNORMAL;
582 fc_exch_timer_set_locked(ep, timer_msec);
583 spin_unlock_bh(&ep->ex_lock);
586 * If not logged into the fabric, don't send ABTS but leave
587 * sequence active until next timeout.
593 * Send an abort for the sequence that timed out.
595 fp = fc_frame_alloc(ep->lp, 0);
597 fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid,
598 FC_TYPE_BLS, FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
599 error = fc_seq_send(ep->lp, sp, fp);
606 * fc_exch_timeout() - Handle exchange timer expiration
607 * @work: The work_struct identifying the exchange that timed out
609 static void fc_exch_timeout(struct work_struct *work)
611 struct fc_exch *ep = container_of(work, struct fc_exch,
613 struct fc_seq *sp = &ep->seq;
614 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
619 FC_EXCH_DBG(ep, "Exchange timed out\n");
621 spin_lock_bh(&ep->ex_lock);
622 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
625 e_stat = ep->esb_stat;
626 if (e_stat & ESB_ST_COMPLETE) {
627 ep->esb_stat = e_stat & ~ESB_ST_REC_QUAL;
628 spin_unlock_bh(&ep->ex_lock);
629 if (e_stat & ESB_ST_REC_QUAL)
636 if (e_stat & ESB_ST_ABNORMAL)
637 rc = fc_exch_done_locked(ep);
638 spin_unlock_bh(&ep->ex_lock);
642 resp(sp, ERR_PTR(-FC_EX_TIMEOUT), arg);
643 fc_seq_exch_abort(sp, 2 * ep->r_a_tov);
647 spin_unlock_bh(&ep->ex_lock);
650 * This release matches the hold taken when the timer was set.
656 * fc_exch_em_alloc() - Allocate an exchange from a specified EM.
657 * @lport: The local port that the exchange is for
658 * @mp: The exchange manager that will allocate the exchange
660 * Returns pointer to allocated fc_exch with exch lock held.
662 static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport,
663 struct fc_exch_mgr *mp)
668 struct fc_exch_pool *pool;
670 /* allocate memory for exchange */
671 ep = mempool_alloc(mp->ep_pool, GFP_ATOMIC);
673 atomic_inc(&mp->stats.no_free_exch);
676 memset(ep, 0, sizeof(*ep));
679 pool = per_cpu_ptr(mp->pool, cpu);
680 spin_lock_bh(&pool->lock);
682 index = pool->next_index;
683 /* allocate new exch from pool */
684 while (fc_exch_ptr_get(pool, index)) {
685 index = index == mp->pool_max_index ? 0 : index + 1;
686 if (index == pool->next_index)
689 pool->next_index = index == mp->pool_max_index ? 0 : index + 1;
691 fc_exch_hold(ep); /* hold for exch in mp */
692 spin_lock_init(&ep->ex_lock);
694 * Hold exch lock for caller to prevent fc_exch_reset()
695 * from releasing exch while fc_exch_alloc() caller is
696 * still working on exch.
698 spin_lock_bh(&ep->ex_lock);
700 fc_exch_ptr_set(pool, index, ep);
701 list_add_tail(&ep->ex_list, &pool->ex_list);
702 fc_seq_alloc(ep, ep->seq_id++);
703 pool->total_exches++;
704 spin_unlock_bh(&pool->lock);
709 ep->oxid = ep->xid = (index << fc_cpu_order | cpu) + mp->min_xid;
713 ep->f_ctl = FC_FC_FIRST_SEQ; /* next seq is first seq */
714 ep->rxid = FC_XID_UNKNOWN;
715 ep->class = mp->class;
716 INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout);
720 spin_unlock_bh(&pool->lock);
721 atomic_inc(&mp->stats.no_free_exch_xid);
722 mempool_free(ep, mp->ep_pool);
727 * fc_exch_alloc() - Allocate an exchange from an EM on a
728 * local port's list of EMs.
729 * @lport: The local port that will own the exchange
730 * @fp: The FC frame that the exchange will be for
732 * This function walks the list of exchange manager(EM)
733 * anchors to select an EM for a new exchange allocation. The
734 * EM is selected when a NULL match function pointer is encountered
735 * or when a call to a match function returns true.
737 static inline struct fc_exch *fc_exch_alloc(struct fc_lport *lport,
740 struct fc_exch_mgr_anchor *ema;
742 list_for_each_entry(ema, &lport->ema_list, ema_list)
743 if (!ema->match || ema->match(fp))
744 return fc_exch_em_alloc(lport, ema->mp);
749 * fc_exch_find() - Lookup and hold an exchange
750 * @mp: The exchange manager to lookup the exchange from
751 * @xid: The XID of the exchange to look up
753 static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid)
755 struct fc_exch_pool *pool;
756 struct fc_exch *ep = NULL;
758 if ((xid >= mp->min_xid) && (xid <= mp->max_xid)) {
759 pool = per_cpu_ptr(mp->pool, xid & fc_cpu_mask);
760 spin_lock_bh(&pool->lock);
761 ep = fc_exch_ptr_get(pool, (xid - mp->min_xid) >> fc_cpu_order);
764 WARN_ON(ep->xid != xid);
766 spin_unlock_bh(&pool->lock);
773 * fc_exch_done() - Indicate that an exchange/sequence tuple is complete and
774 * the memory allocated for the related objects may be freed.
775 * @sp: The sequence that has completed
777 static void fc_exch_done(struct fc_seq *sp)
779 struct fc_exch *ep = fc_seq_exch(sp);
782 spin_lock_bh(&ep->ex_lock);
783 rc = fc_exch_done_locked(ep);
784 spin_unlock_bh(&ep->ex_lock);
790 * fc_exch_resp() - Allocate a new exchange for a response frame
791 * @lport: The local port that the exchange was for
792 * @mp: The exchange manager to allocate the exchange from
793 * @fp: The response frame
795 * Sets the responder ID in the frame header.
797 static struct fc_exch *fc_exch_resp(struct fc_lport *lport,
798 struct fc_exch_mgr *mp,
802 struct fc_frame_header *fh;
804 ep = fc_exch_alloc(lport, fp);
806 ep->class = fc_frame_class(fp);
809 * Set EX_CTX indicating we're responding on this exchange.
811 ep->f_ctl |= FC_FC_EX_CTX; /* we're responding */
812 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not new */
813 fh = fc_frame_header_get(fp);
814 ep->sid = ntoh24(fh->fh_d_id);
815 ep->did = ntoh24(fh->fh_s_id);
819 * Allocated exchange has placed the XID in the
820 * originator field. Move it to the responder field,
821 * and set the originator XID from the frame.
824 ep->oxid = ntohs(fh->fh_ox_id);
825 ep->esb_stat |= ESB_ST_RESP | ESB_ST_SEQ_INIT;
826 if ((ntoh24(fh->fh_f_ctl) & FC_FC_SEQ_INIT) == 0)
827 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
829 fc_exch_hold(ep); /* hold for caller */
830 spin_unlock_bh(&ep->ex_lock); /* lock from fc_exch_alloc */
836 * fc_seq_lookup_recip() - Find a sequence where the other end
837 * originated the sequence
838 * @lport: The local port that the frame was sent to
839 * @mp: The Exchange Manager to lookup the exchange from
840 * @fp: The frame associated with the sequence we're looking for
842 * If fc_pf_rjt_reason is FC_RJT_NONE then this function will have a hold
843 * on the ep that should be released by the caller.
845 static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport,
846 struct fc_exch_mgr *mp,
849 struct fc_frame_header *fh = fc_frame_header_get(fp);
850 struct fc_exch *ep = NULL;
851 struct fc_seq *sp = NULL;
852 enum fc_pf_rjt_reason reject = FC_RJT_NONE;
856 f_ctl = ntoh24(fh->fh_f_ctl);
857 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != 0);
860 * Lookup or create the exchange if we will be creating the sequence.
862 if (f_ctl & FC_FC_EX_CTX) {
863 xid = ntohs(fh->fh_ox_id); /* we originated exch */
864 ep = fc_exch_find(mp, xid);
866 atomic_inc(&mp->stats.xid_not_found);
867 reject = FC_RJT_OX_ID;
870 if (ep->rxid == FC_XID_UNKNOWN)
871 ep->rxid = ntohs(fh->fh_rx_id);
872 else if (ep->rxid != ntohs(fh->fh_rx_id)) {
873 reject = FC_RJT_OX_ID;
877 xid = ntohs(fh->fh_rx_id); /* we are the responder */
880 * Special case for MDS issuing an ELS TEST with a
882 * XXX take this out once we do the proper reject.
884 if (xid == 0 && fh->fh_r_ctl == FC_RCTL_ELS_REQ &&
885 fc_frame_payload_op(fp) == ELS_TEST) {
886 fh->fh_rx_id = htons(FC_XID_UNKNOWN);
887 xid = FC_XID_UNKNOWN;
891 * new sequence - find the exchange
893 ep = fc_exch_find(mp, xid);
894 if ((f_ctl & FC_FC_FIRST_SEQ) && fc_sof_is_init(fr_sof(fp))) {
896 atomic_inc(&mp->stats.xid_busy);
897 reject = FC_RJT_RX_ID;
900 ep = fc_exch_resp(lport, mp, fp);
902 reject = FC_RJT_EXCH_EST; /* XXX */
905 xid = ep->xid; /* get our XID */
907 atomic_inc(&mp->stats.xid_not_found);
908 reject = FC_RJT_RX_ID; /* XID not found */
914 * At this point, we have the exchange held.
915 * Find or create the sequence.
917 if (fc_sof_is_init(fr_sof(fp))) {
919 sp->ssb_stat |= SSB_ST_RESP;
920 sp->id = fh->fh_seq_id;
923 if (sp->id != fh->fh_seq_id) {
924 atomic_inc(&mp->stats.seq_not_found);
925 reject = FC_RJT_SEQ_ID; /* sequence/exch should exist */
929 WARN_ON(ep != fc_seq_exch(sp));
931 if (f_ctl & FC_FC_SEQ_INIT)
932 ep->esb_stat |= ESB_ST_SEQ_INIT;
938 fc_exch_done(&ep->seq);
939 fc_exch_release(ep); /* hold from fc_exch_find/fc_exch_resp */
944 * fc_seq_lookup_orig() - Find a sequence where this end
945 * originated the sequence
946 * @mp: The Exchange Manager to lookup the exchange from
947 * @fp: The frame associated with the sequence we're looking for
949 * Does not hold the sequence for the caller.
951 static struct fc_seq *fc_seq_lookup_orig(struct fc_exch_mgr *mp,
954 struct fc_frame_header *fh = fc_frame_header_get(fp);
956 struct fc_seq *sp = NULL;
960 f_ctl = ntoh24(fh->fh_f_ctl);
961 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != FC_FC_SEQ_CTX);
962 xid = ntohs((f_ctl & FC_FC_EX_CTX) ? fh->fh_ox_id : fh->fh_rx_id);
963 ep = fc_exch_find(mp, xid);
966 if (ep->seq.id == fh->fh_seq_id) {
968 * Save the RX_ID if we didn't previously know it.
971 if ((f_ctl & FC_FC_EX_CTX) != 0 &&
972 ep->rxid == FC_XID_UNKNOWN) {
973 ep->rxid = ntohs(fh->fh_rx_id);
981 * fc_exch_set_addr() - Set the source and destination IDs for an exchange
982 * @ep: The exchange to set the addresses for
983 * @orig_id: The originator's ID
984 * @resp_id: The responder's ID
986 * Note this must be done before the first sequence of the exchange is sent.
988 static void fc_exch_set_addr(struct fc_exch *ep,
989 u32 orig_id, u32 resp_id)
992 if (ep->esb_stat & ESB_ST_RESP) {
1002 * fc_seq_els_rsp_send() - Send an ELS response using infomation from
1003 * the existing sequence/exchange.
1004 * @fp: The received frame
1005 * @els_cmd: The ELS command to be sent
1006 * @els_data: The ELS data to be sent
1008 * The received frame is not freed.
1010 static void fc_seq_els_rsp_send(struct fc_frame *fp, enum fc_els_cmd els_cmd,
1011 struct fc_seq_els_data *els_data)
1015 fc_seq_ls_rjt(fp, els_data->reason, els_data->explan);
1021 fc_exch_els_rrq(fp);
1024 fc_exch_els_rec(fp);
1027 FC_LPORT_DBG(fr_dev(fp), "Invalid ELS CMD:%x\n", els_cmd);
1032 * fc_seq_send_last() - Send a sequence that is the last in the exchange
1033 * @sp: The sequence that is to be sent
1034 * @fp: The frame that will be sent on the sequence
1035 * @rctl: The R_CTL information to be sent
1036 * @fh_type: The frame header type
1038 static void fc_seq_send_last(struct fc_seq *sp, struct fc_frame *fp,
1039 enum fc_rctl rctl, enum fc_fh_type fh_type)
1042 struct fc_exch *ep = fc_seq_exch(sp);
1044 f_ctl = FC_FC_LAST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT;
1046 fc_fill_fc_hdr(fp, rctl, ep->did, ep->sid, fh_type, f_ctl, 0);
1047 fc_seq_send(ep->lp, sp, fp);
1051 * fc_seq_send_ack() - Send an acknowledgement that we've received a frame
1052 * @sp: The sequence to send the ACK on
1053 * @rx_fp: The received frame that is being acknoledged
1055 * Send ACK_1 (or equiv.) indicating we received something.
1057 static void fc_seq_send_ack(struct fc_seq *sp, const struct fc_frame *rx_fp)
1059 struct fc_frame *fp;
1060 struct fc_frame_header *rx_fh;
1061 struct fc_frame_header *fh;
1062 struct fc_exch *ep = fc_seq_exch(sp);
1063 struct fc_lport *lport = ep->lp;
1067 * Don't send ACKs for class 3.
1069 if (fc_sof_needs_ack(fr_sof(rx_fp))) {
1070 fp = fc_frame_alloc(lport, 0);
1074 fh = fc_frame_header_get(fp);
1075 fh->fh_r_ctl = FC_RCTL_ACK_1;
1076 fh->fh_type = FC_TYPE_BLS;
1079 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
1080 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
1081 * Bits 9-8 are meaningful (retransmitted or unidirectional).
1082 * Last ACK uses bits 7-6 (continue sequence),
1083 * bits 5-4 are meaningful (what kind of ACK to use).
1085 rx_fh = fc_frame_header_get(rx_fp);
1086 f_ctl = ntoh24(rx_fh->fh_f_ctl);
1087 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
1088 FC_FC_FIRST_SEQ | FC_FC_LAST_SEQ |
1089 FC_FC_END_SEQ | FC_FC_END_CONN | FC_FC_SEQ_INIT |
1090 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
1091 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
1092 hton24(fh->fh_f_ctl, f_ctl);
1094 fc_exch_setup_hdr(ep, fp, f_ctl);
1095 fh->fh_seq_id = rx_fh->fh_seq_id;
1096 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
1097 fh->fh_parm_offset = htonl(1); /* ack single frame */
1099 fr_sof(fp) = fr_sof(rx_fp);
1100 if (f_ctl & FC_FC_END_SEQ)
1101 fr_eof(fp) = FC_EOF_T;
1103 fr_eof(fp) = FC_EOF_N;
1105 lport->tt.frame_send(lport, fp);
1110 * fc_exch_send_ba_rjt() - Send BLS Reject
1111 * @rx_fp: The frame being rejected
1112 * @reason: The reason the frame is being rejected
1113 * @explan: The explaination for the rejection
1115 * This is for rejecting BA_ABTS only.
1117 static void fc_exch_send_ba_rjt(struct fc_frame *rx_fp,
1118 enum fc_ba_rjt_reason reason,
1119 enum fc_ba_rjt_explan explan)
1121 struct fc_frame *fp;
1122 struct fc_frame_header *rx_fh;
1123 struct fc_frame_header *fh;
1124 struct fc_ba_rjt *rp;
1125 struct fc_lport *lport;
1128 lport = fr_dev(rx_fp);
1129 fp = fc_frame_alloc(lport, sizeof(*rp));
1132 fh = fc_frame_header_get(fp);
1133 rx_fh = fc_frame_header_get(rx_fp);
1135 memset(fh, 0, sizeof(*fh) + sizeof(*rp));
1137 rp = fc_frame_payload_get(fp, sizeof(*rp));
1138 rp->br_reason = reason;
1139 rp->br_explan = explan;
1142 * seq_id, cs_ctl, df_ctl and param/offset are zero.
1144 memcpy(fh->fh_s_id, rx_fh->fh_d_id, 3);
1145 memcpy(fh->fh_d_id, rx_fh->fh_s_id, 3);
1146 fh->fh_ox_id = rx_fh->fh_ox_id;
1147 fh->fh_rx_id = rx_fh->fh_rx_id;
1148 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
1149 fh->fh_r_ctl = FC_RCTL_BA_RJT;
1150 fh->fh_type = FC_TYPE_BLS;
1153 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
1154 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
1155 * Bits 9-8 are meaningful (retransmitted or unidirectional).
1156 * Last ACK uses bits 7-6 (continue sequence),
1157 * bits 5-4 are meaningful (what kind of ACK to use).
1158 * Always set LAST_SEQ, END_SEQ.
1160 f_ctl = ntoh24(rx_fh->fh_f_ctl);
1161 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
1162 FC_FC_END_CONN | FC_FC_SEQ_INIT |
1163 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
1164 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
1165 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
1166 f_ctl &= ~FC_FC_FIRST_SEQ;
1167 hton24(fh->fh_f_ctl, f_ctl);
1169 fr_sof(fp) = fc_sof_class(fr_sof(rx_fp));
1170 fr_eof(fp) = FC_EOF_T;
1171 if (fc_sof_needs_ack(fr_sof(fp)))
1172 fr_eof(fp) = FC_EOF_N;
1174 lport->tt.frame_send(lport, fp);
1178 * fc_exch_recv_abts() - Handle an incoming ABTS
1179 * @ep: The exchange the abort was on
1180 * @rx_fp: The ABTS frame
1182 * This would be for target mode usually, but could be due to lost
1183 * FCP transfer ready, confirm or RRQ. We always handle this as an
1184 * exchange abort, ignoring the parameter.
1186 static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp)
1188 struct fc_frame *fp;
1189 struct fc_ba_acc *ap;
1190 struct fc_frame_header *fh;
1195 spin_lock_bh(&ep->ex_lock);
1196 if (ep->esb_stat & ESB_ST_COMPLETE) {
1197 spin_unlock_bh(&ep->ex_lock);
1200 if (!(ep->esb_stat & ESB_ST_REC_QUAL))
1201 fc_exch_hold(ep); /* hold for REC_QUAL */
1202 ep->esb_stat |= ESB_ST_ABNORMAL | ESB_ST_REC_QUAL;
1203 fc_exch_timer_set_locked(ep, ep->r_a_tov);
1205 fp = fc_frame_alloc(ep->lp, sizeof(*ap));
1207 spin_unlock_bh(&ep->ex_lock);
1210 fh = fc_frame_header_get(fp);
1211 ap = fc_frame_payload_get(fp, sizeof(*ap));
1212 memset(ap, 0, sizeof(*ap));
1214 ap->ba_high_seq_cnt = htons(0xffff);
1215 if (sp->ssb_stat & SSB_ST_RESP) {
1216 ap->ba_seq_id = sp->id;
1217 ap->ba_seq_id_val = FC_BA_SEQ_ID_VAL;
1218 ap->ba_high_seq_cnt = fh->fh_seq_cnt;
1219 ap->ba_low_seq_cnt = htons(sp->cnt);
1221 sp = fc_seq_start_next_locked(sp);
1222 spin_unlock_bh(&ep->ex_lock);
1223 fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS);
1224 fc_frame_free(rx_fp);
1228 fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID);
1230 fc_frame_free(rx_fp);
1234 * fc_seq_assign() - Assign exchange and sequence for incoming request
1235 * @lport: The local port that received the request
1236 * @fp: The request frame
1238 * On success, the sequence pointer will be returned and also in fr_seq(@fp).
1240 static struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp)
1242 struct fc_exch_mgr_anchor *ema;
1244 WARN_ON(lport != fr_dev(fp));
1245 WARN_ON(fr_seq(fp));
1248 list_for_each_entry(ema, &lport->ema_list, ema_list)
1249 if ((!ema->match || ema->match(fp)) &&
1250 fc_seq_lookup_recip(lport, ema->mp, fp) != FC_RJT_NONE)
1256 * fc_exch_recv_req() - Handler for an incoming request
1257 * @lport: The local port that received the request
1258 * @mp: The EM that the exchange is on
1259 * @fp: The request frame
1261 * This is used when the other end is originating the exchange
1264 static void fc_exch_recv_req(struct fc_lport *lport, struct fc_exch_mgr *mp,
1265 struct fc_frame *fp)
1267 struct fc_frame_header *fh = fc_frame_header_get(fp);
1268 struct fc_seq *sp = NULL;
1269 struct fc_exch *ep = NULL;
1270 enum fc_pf_rjt_reason reject;
1272 /* We can have the wrong fc_lport at this point with NPIV, which is a
1273 * problem now that we know a new exchange needs to be allocated
1275 lport = fc_vport_id_lookup(lport, ntoh24(fh->fh_d_id));
1282 BUG_ON(fr_seq(fp)); /* XXX remove later */
1285 * If the RX_ID is 0xffff, don't allocate an exchange.
1286 * The upper-level protocol may request one later, if needed.
1288 if (fh->fh_rx_id == htons(FC_XID_UNKNOWN))
1289 return lport->tt.lport_recv(lport, fp);
1291 reject = fc_seq_lookup_recip(lport, mp, fp);
1292 if (reject == FC_RJT_NONE) {
1293 sp = fr_seq(fp); /* sequence will be held */
1294 ep = fc_seq_exch(sp);
1295 fc_seq_send_ack(sp, fp);
1296 ep->encaps = fr_encaps(fp);
1299 * Call the receive function.
1301 * The receive function may allocate a new sequence
1302 * over the old one, so we shouldn't change the
1303 * sequence after this.
1305 * The frame will be freed by the receive function.
1306 * If new exch resp handler is valid then call that
1310 ep->resp(sp, fp, ep->arg);
1312 lport->tt.lport_recv(lport, fp);
1313 fc_exch_release(ep); /* release from lookup */
1315 FC_LPORT_DBG(lport, "exch/seq lookup failed: reject %x\n",
1322 * fc_exch_recv_seq_resp() - Handler for an incoming response where the other
1323 * end is the originator of the sequence that is a
1324 * response to our initial exchange
1325 * @mp: The EM that the exchange is on
1326 * @fp: The response frame
1328 static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1330 struct fc_frame_header *fh = fc_frame_header_get(fp);
1335 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1339 ep = fc_exch_find(mp, ntohs(fh->fh_ox_id));
1341 atomic_inc(&mp->stats.xid_not_found);
1344 if (ep->esb_stat & ESB_ST_COMPLETE) {
1345 atomic_inc(&mp->stats.xid_not_found);
1348 if (ep->rxid == FC_XID_UNKNOWN)
1349 ep->rxid = ntohs(fh->fh_rx_id);
1350 if (ep->sid != 0 && ep->sid != ntoh24(fh->fh_d_id)) {
1351 atomic_inc(&mp->stats.xid_not_found);
1354 if (ep->did != ntoh24(fh->fh_s_id) &&
1355 ep->did != FC_FID_FLOGI) {
1356 atomic_inc(&mp->stats.xid_not_found);
1361 if (fc_sof_is_init(sof)) {
1362 sp->ssb_stat |= SSB_ST_RESP;
1363 sp->id = fh->fh_seq_id;
1364 } else if (sp->id != fh->fh_seq_id) {
1365 atomic_inc(&mp->stats.seq_not_found);
1369 f_ctl = ntoh24(fh->fh_f_ctl);
1371 if (f_ctl & FC_FC_SEQ_INIT)
1372 ep->esb_stat |= ESB_ST_SEQ_INIT;
1374 if (fc_sof_needs_ack(sof))
1375 fc_seq_send_ack(sp, fp);
1377 ex_resp_arg = ep->arg;
1379 if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T &&
1380 (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) ==
1381 (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) {
1382 spin_lock_bh(&ep->ex_lock);
1383 rc = fc_exch_done_locked(ep);
1384 WARN_ON(fc_seq_exch(sp) != ep);
1385 spin_unlock_bh(&ep->ex_lock);
1391 * Call the receive function.
1392 * The sequence is held (has a refcnt) for us,
1393 * but not for the receive function.
1395 * The receive function may allocate a new sequence
1396 * over the old one, so we shouldn't change the
1397 * sequence after this.
1399 * The frame will be freed by the receive function.
1400 * If new exch resp handler is valid then call that
1404 resp(sp, fp, ex_resp_arg);
1407 fc_exch_release(ep);
1410 fc_exch_release(ep);
1416 * fc_exch_recv_resp() - Handler for a sequence where other end is
1417 * responding to our sequence
1418 * @mp: The EM that the exchange is on
1419 * @fp: The response frame
1421 static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1425 sp = fc_seq_lookup_orig(mp, fp); /* doesn't hold sequence */
1428 atomic_inc(&mp->stats.xid_not_found);
1430 atomic_inc(&mp->stats.non_bls_resp);
1436 * fc_exch_abts_resp() - Handler for a response to an ABT
1437 * @ep: The exchange that the frame is on
1438 * @fp: The response frame
1440 * This response would be to an ABTS cancelling an exchange or sequence.
1441 * The response can be either BA_ACC or BA_RJT
1443 static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp)
1445 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1447 struct fc_frame_header *fh;
1448 struct fc_ba_acc *ap;
1452 int rc = 1, has_rec = 0;
1454 fh = fc_frame_header_get(fp);
1455 FC_EXCH_DBG(ep, "exch: BLS rctl %x - %s\n", fh->fh_r_ctl,
1456 fc_exch_rctl_name(fh->fh_r_ctl));
1458 if (cancel_delayed_work_sync(&ep->timeout_work))
1459 fc_exch_release(ep); /* release from pending timer hold */
1461 spin_lock_bh(&ep->ex_lock);
1462 switch (fh->fh_r_ctl) {
1463 case FC_RCTL_BA_ACC:
1464 ap = fc_frame_payload_get(fp, sizeof(*ap));
1469 * Decide whether to establish a Recovery Qualifier.
1470 * We do this if there is a non-empty SEQ_CNT range and
1471 * SEQ_ID is the same as the one we aborted.
1473 low = ntohs(ap->ba_low_seq_cnt);
1474 high = ntohs(ap->ba_high_seq_cnt);
1475 if ((ep->esb_stat & ESB_ST_REC_QUAL) == 0 &&
1476 (ap->ba_seq_id_val != FC_BA_SEQ_ID_VAL ||
1477 ap->ba_seq_id == ep->seq_id) && low != high) {
1478 ep->esb_stat |= ESB_ST_REC_QUAL;
1479 fc_exch_hold(ep); /* hold for recovery qualifier */
1483 case FC_RCTL_BA_RJT:
1490 ex_resp_arg = ep->arg;
1492 /* do we need to do some other checks here. Can we reuse more of
1493 * fc_exch_recv_seq_resp
1497 * do we want to check END_SEQ as well as LAST_SEQ here?
1499 if (ep->fh_type != FC_TYPE_FCP &&
1500 ntoh24(fh->fh_f_ctl) & FC_FC_LAST_SEQ)
1501 rc = fc_exch_done_locked(ep);
1502 spin_unlock_bh(&ep->ex_lock);
1507 resp(sp, fp, ex_resp_arg);
1512 fc_exch_timer_set(ep, ep->r_a_tov);
1517 * fc_exch_recv_bls() - Handler for a BLS sequence
1518 * @mp: The EM that the exchange is on
1519 * @fp: The request frame
1521 * The BLS frame is always a sequence initiated by the remote side.
1522 * We may be either the originator or recipient of the exchange.
1524 static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp)
1526 struct fc_frame_header *fh;
1530 fh = fc_frame_header_get(fp);
1531 f_ctl = ntoh24(fh->fh_f_ctl);
1534 ep = fc_exch_find(mp, (f_ctl & FC_FC_EX_CTX) ?
1535 ntohs(fh->fh_ox_id) : ntohs(fh->fh_rx_id));
1536 if (ep && (f_ctl & FC_FC_SEQ_INIT)) {
1537 spin_lock_bh(&ep->ex_lock);
1538 ep->esb_stat |= ESB_ST_SEQ_INIT;
1539 spin_unlock_bh(&ep->ex_lock);
1541 if (f_ctl & FC_FC_SEQ_CTX) {
1543 * A response to a sequence we initiated.
1544 * This should only be ACKs for class 2 or F.
1546 switch (fh->fh_r_ctl) {
1551 FC_EXCH_DBG(ep, "BLS rctl %x - %s received",
1553 fc_exch_rctl_name(fh->fh_r_ctl));
1558 switch (fh->fh_r_ctl) {
1559 case FC_RCTL_BA_RJT:
1560 case FC_RCTL_BA_ACC:
1562 fc_exch_abts_resp(ep, fp);
1566 case FC_RCTL_BA_ABTS:
1567 fc_exch_recv_abts(ep, fp);
1569 default: /* ignore junk */
1575 fc_exch_release(ep); /* release hold taken by fc_exch_find */
1579 * fc_seq_ls_acc() - Accept sequence with LS_ACC
1580 * @rx_fp: The received frame, not freed here.
1582 * If this fails due to allocation or transmit congestion, assume the
1583 * originator will repeat the sequence.
1585 static void fc_seq_ls_acc(struct fc_frame *rx_fp)
1587 struct fc_lport *lport;
1588 struct fc_els_ls_acc *acc;
1589 struct fc_frame *fp;
1591 lport = fr_dev(rx_fp);
1592 fp = fc_frame_alloc(lport, sizeof(*acc));
1595 acc = fc_frame_payload_get(fp, sizeof(*acc));
1596 memset(acc, 0, sizeof(*acc));
1597 acc->la_cmd = ELS_LS_ACC;
1598 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
1599 lport->tt.frame_send(lport, fp);
1603 * fc_seq_ls_rjt() - Reject a sequence with ELS LS_RJT
1604 * @rx_fp: The received frame, not freed here.
1605 * @reason: The reason the sequence is being rejected
1606 * @explan: The explanation for the rejection
1608 * If this fails due to allocation or transmit congestion, assume the
1609 * originator will repeat the sequence.
1611 static void fc_seq_ls_rjt(struct fc_frame *rx_fp, enum fc_els_rjt_reason reason,
1612 enum fc_els_rjt_explan explan)
1614 struct fc_lport *lport;
1615 struct fc_els_ls_rjt *rjt;
1616 struct fc_frame *fp;
1618 lport = fr_dev(rx_fp);
1619 fp = fc_frame_alloc(lport, sizeof(*rjt));
1622 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1623 memset(rjt, 0, sizeof(*rjt));
1624 rjt->er_cmd = ELS_LS_RJT;
1625 rjt->er_reason = reason;
1626 rjt->er_explan = explan;
1627 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
1628 lport->tt.frame_send(lport, fp);
1632 * fc_exch_reset() - Reset an exchange
1633 * @ep: The exchange to be reset
1635 static void fc_exch_reset(struct fc_exch *ep)
1638 void (*resp)(struct fc_seq *, struct fc_frame *, void *);
1642 spin_lock_bh(&ep->ex_lock);
1643 ep->state |= FC_EX_RST_CLEANUP;
1644 if (cancel_delayed_work(&ep->timeout_work))
1645 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */
1648 if (ep->esb_stat & ESB_ST_REC_QUAL)
1649 atomic_dec(&ep->ex_refcnt); /* drop hold for rec_qual */
1650 ep->esb_stat &= ~ESB_ST_REC_QUAL;
1653 rc = fc_exch_done_locked(ep);
1654 spin_unlock_bh(&ep->ex_lock);
1659 resp(sp, ERR_PTR(-FC_EX_CLOSED), arg);
1663 * fc_exch_pool_reset() - Reset a per cpu exchange pool
1664 * @lport: The local port that the exchange pool is on
1665 * @pool: The exchange pool to be reset
1666 * @sid: The source ID
1667 * @did: The destination ID
1669 * Resets a per cpu exches pool, releasing all of its sequences
1670 * and exchanges. If sid is non-zero then reset only exchanges
1671 * we sourced from the local port's FID. If did is non-zero then
1672 * only reset exchanges destined for the local port's FID.
1674 static void fc_exch_pool_reset(struct fc_lport *lport,
1675 struct fc_exch_pool *pool,
1679 struct fc_exch *next;
1681 spin_lock_bh(&pool->lock);
1683 list_for_each_entry_safe(ep, next, &pool->ex_list, ex_list) {
1684 if ((lport == ep->lp) &&
1685 (sid == 0 || sid == ep->sid) &&
1686 (did == 0 || did == ep->did)) {
1688 spin_unlock_bh(&pool->lock);
1692 fc_exch_release(ep);
1693 spin_lock_bh(&pool->lock);
1696 * must restart loop incase while lock
1697 * was down multiple eps were released.
1702 spin_unlock_bh(&pool->lock);
1706 * fc_exch_mgr_reset() - Reset all EMs of a local port
1707 * @lport: The local port whose EMs are to be reset
1708 * @sid: The source ID
1709 * @did: The destination ID
1711 * Reset all EMs associated with a given local port. Release all
1712 * sequences and exchanges. If sid is non-zero then reset only the
1713 * exchanges sent from the local port's FID. If did is non-zero then
1714 * reset only exchanges destined for the local port's FID.
1716 void fc_exch_mgr_reset(struct fc_lport *lport, u32 sid, u32 did)
1718 struct fc_exch_mgr_anchor *ema;
1721 list_for_each_entry(ema, &lport->ema_list, ema_list) {
1722 for_each_possible_cpu(cpu)
1723 fc_exch_pool_reset(lport,
1724 per_cpu_ptr(ema->mp->pool, cpu),
1728 EXPORT_SYMBOL(fc_exch_mgr_reset);
1731 * fc_exch_lookup() - find an exchange
1732 * @lport: The local port
1733 * @xid: The exchange ID
1735 * Returns exchange pointer with hold for caller, or NULL if not found.
1737 static struct fc_exch *fc_exch_lookup(struct fc_lport *lport, u32 xid)
1739 struct fc_exch_mgr_anchor *ema;
1741 list_for_each_entry(ema, &lport->ema_list, ema_list)
1742 if (ema->mp->min_xid <= xid && xid <= ema->mp->max_xid)
1743 return fc_exch_find(ema->mp, xid);
1748 * fc_exch_els_rec() - Handler for ELS REC (Read Exchange Concise) requests
1749 * @rfp: The REC frame, not freed here.
1751 * Note that the requesting port may be different than the S_ID in the request.
1753 static void fc_exch_els_rec(struct fc_frame *rfp)
1755 struct fc_lport *lport;
1756 struct fc_frame *fp;
1758 struct fc_els_rec *rp;
1759 struct fc_els_rec_acc *acc;
1760 enum fc_els_rjt_reason reason = ELS_RJT_LOGIC;
1761 enum fc_els_rjt_explan explan;
1766 lport = fr_dev(rfp);
1767 rp = fc_frame_payload_get(rfp, sizeof(*rp));
1768 explan = ELS_EXPL_INV_LEN;
1771 sid = ntoh24(rp->rec_s_id);
1772 rxid = ntohs(rp->rec_rx_id);
1773 oxid = ntohs(rp->rec_ox_id);
1775 ep = fc_exch_lookup(lport,
1776 sid == fc_host_port_id(lport->host) ? oxid : rxid);
1777 explan = ELS_EXPL_OXID_RXID;
1780 if (ep->oid != sid || oxid != ep->oxid)
1782 if (rxid != FC_XID_UNKNOWN && rxid != ep->rxid)
1784 fp = fc_frame_alloc(lport, sizeof(*acc));
1788 acc = fc_frame_payload_get(fp, sizeof(*acc));
1789 memset(acc, 0, sizeof(*acc));
1790 acc->reca_cmd = ELS_LS_ACC;
1791 acc->reca_ox_id = rp->rec_ox_id;
1792 memcpy(acc->reca_ofid, rp->rec_s_id, 3);
1793 acc->reca_rx_id = htons(ep->rxid);
1794 if (ep->sid == ep->oid)
1795 hton24(acc->reca_rfid, ep->did);
1797 hton24(acc->reca_rfid, ep->sid);
1798 acc->reca_fc4value = htonl(ep->seq.rec_data);
1799 acc->reca_e_stat = htonl(ep->esb_stat & (ESB_ST_RESP |
1802 fc_fill_reply_hdr(fp, rfp, FC_RCTL_ELS_REP, 0);
1803 lport->tt.frame_send(lport, fp);
1805 fc_exch_release(ep);
1809 fc_exch_release(ep);
1811 fc_seq_ls_rjt(rfp, reason, explan);
1815 * fc_exch_rrq_resp() - Handler for RRQ responses
1816 * @sp: The sequence that the RRQ is on
1817 * @fp: The RRQ frame
1818 * @arg: The exchange that the RRQ is on
1820 * TODO: fix error handler.
1822 static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg)
1824 struct fc_exch *aborted_ep = arg;
1828 int err = PTR_ERR(fp);
1830 if (err == -FC_EX_CLOSED || err == -FC_EX_TIMEOUT)
1832 FC_EXCH_DBG(aborted_ep, "Cannot process RRQ, "
1833 "frame error %d\n", err);
1837 op = fc_frame_payload_op(fp);
1842 FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ");
1847 FC_EXCH_DBG(aborted_ep, "unexpected response op %x "
1853 fc_exch_done(&aborted_ep->seq);
1854 /* drop hold for rec qual */
1855 fc_exch_release(aborted_ep);
1860 * fc_exch_seq_send() - Send a frame using a new exchange and sequence
1861 * @lport: The local port to send the frame on
1862 * @fp: The frame to be sent
1863 * @resp: The response handler for this request
1864 * @destructor: The destructor for the exchange
1865 * @arg: The argument to be passed to the response handler
1866 * @timer_msec: The timeout period for the exchange
1868 * The frame pointer with some of the header's fields must be
1869 * filled before calling this routine, those fields are:
1876 * - parameter or relative offset
1878 static struct fc_seq *fc_exch_seq_send(struct fc_lport *lport,
1879 struct fc_frame *fp,
1880 void (*resp)(struct fc_seq *,
1881 struct fc_frame *fp,
1883 void (*destructor)(struct fc_seq *,
1885 void *arg, u32 timer_msec)
1888 struct fc_seq *sp = NULL;
1889 struct fc_frame_header *fh;
1892 ep = fc_exch_alloc(lport, fp);
1897 ep->esb_stat |= ESB_ST_SEQ_INIT;
1898 fh = fc_frame_header_get(fp);
1899 fc_exch_set_addr(ep, ntoh24(fh->fh_s_id), ntoh24(fh->fh_d_id));
1901 ep->destructor = destructor;
1903 ep->r_a_tov = FC_DEF_R_A_TOV;
1907 ep->fh_type = fh->fh_type; /* save for possbile timeout handling */
1908 ep->f_ctl = ntoh24(fh->fh_f_ctl);
1909 fc_exch_setup_hdr(ep, fp, ep->f_ctl);
1912 if (ep->xid <= lport->lro_xid && fh->fh_r_ctl == FC_RCTL_DD_UNSOL_CMD)
1913 fc_fcp_ddp_setup(fr_fsp(fp), ep->xid);
1915 if (unlikely(lport->tt.frame_send(lport, fp)))
1919 fc_exch_timer_set_locked(ep, timer_msec);
1920 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not first seq */
1922 if (ep->f_ctl & FC_FC_SEQ_INIT)
1923 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
1924 spin_unlock_bh(&ep->ex_lock);
1927 rc = fc_exch_done_locked(ep);
1928 spin_unlock_bh(&ep->ex_lock);
1935 * fc_exch_rrq() - Send an ELS RRQ (Reinstate Recovery Qualifier) command
1936 * @ep: The exchange to send the RRQ on
1938 * This tells the remote port to stop blocking the use of
1939 * the exchange and the seq_cnt range.
1941 static void fc_exch_rrq(struct fc_exch *ep)
1943 struct fc_lport *lport;
1944 struct fc_els_rrq *rrq;
1945 struct fc_frame *fp;
1950 fp = fc_frame_alloc(lport, sizeof(*rrq));
1954 rrq = fc_frame_payload_get(fp, sizeof(*rrq));
1955 memset(rrq, 0, sizeof(*rrq));
1956 rrq->rrq_cmd = ELS_RRQ;
1957 hton24(rrq->rrq_s_id, ep->sid);
1958 rrq->rrq_ox_id = htons(ep->oxid);
1959 rrq->rrq_rx_id = htons(ep->rxid);
1962 if (ep->esb_stat & ESB_ST_RESP)
1965 fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, did,
1966 lport->port_id, FC_TYPE_ELS,
1967 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1969 if (fc_exch_seq_send(lport, fp, fc_exch_rrq_resp, NULL, ep,
1974 spin_lock_bh(&ep->ex_lock);
1975 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) {
1976 spin_unlock_bh(&ep->ex_lock);
1977 /* drop hold for rec qual */
1978 fc_exch_release(ep);
1981 ep->esb_stat |= ESB_ST_REC_QUAL;
1982 fc_exch_timer_set_locked(ep, ep->r_a_tov);
1983 spin_unlock_bh(&ep->ex_lock);
1987 * fc_exch_els_rrq() - Handler for ELS RRQ (Reset Recovery Qualifier) requests
1988 * @fp: The RRQ frame, not freed here.
1990 static void fc_exch_els_rrq(struct fc_frame *fp)
1992 struct fc_lport *lport;
1993 struct fc_exch *ep = NULL; /* request or subject exchange */
1994 struct fc_els_rrq *rp;
1997 enum fc_els_rjt_explan explan;
2000 rp = fc_frame_payload_get(fp, sizeof(*rp));
2001 explan = ELS_EXPL_INV_LEN;
2006 * lookup subject exchange.
2008 sid = ntoh24(rp->rrq_s_id); /* subject source */
2009 xid = fc_host_port_id(lport->host) == sid ?
2010 ntohs(rp->rrq_ox_id) : ntohs(rp->rrq_rx_id);
2011 ep = fc_exch_lookup(lport, xid);
2012 explan = ELS_EXPL_OXID_RXID;
2015 spin_lock_bh(&ep->ex_lock);
2016 if (ep->oxid != ntohs(rp->rrq_ox_id))
2018 if (ep->rxid != ntohs(rp->rrq_rx_id) &&
2019 ep->rxid != FC_XID_UNKNOWN)
2021 explan = ELS_EXPL_SID;
2026 * Clear Recovery Qualifier state, and cancel timer if complete.
2028 if (ep->esb_stat & ESB_ST_REC_QUAL) {
2029 ep->esb_stat &= ~ESB_ST_REC_QUAL;
2030 atomic_dec(&ep->ex_refcnt); /* drop hold for rec qual */
2032 if (ep->esb_stat & ESB_ST_COMPLETE) {
2033 if (cancel_delayed_work(&ep->timeout_work))
2034 atomic_dec(&ep->ex_refcnt); /* drop timer hold */
2037 spin_unlock_bh(&ep->ex_lock);
2046 spin_unlock_bh(&ep->ex_lock);
2048 fc_seq_ls_rjt(fp, ELS_RJT_LOGIC, explan);
2051 fc_exch_release(ep); /* drop hold from fc_exch_find */
2055 * fc_exch_mgr_add() - Add an exchange manager to a local port's list of EMs
2056 * @lport: The local port to add the exchange manager to
2057 * @mp: The exchange manager to be added to the local port
2058 * @match: The match routine that indicates when this EM should be used
2060 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport,
2061 struct fc_exch_mgr *mp,
2062 bool (*match)(struct fc_frame *))
2064 struct fc_exch_mgr_anchor *ema;
2066 ema = kmalloc(sizeof(*ema), GFP_ATOMIC);
2072 /* add EM anchor to EM anchors list */
2073 list_add_tail(&ema->ema_list, &lport->ema_list);
2074 kref_get(&mp->kref);
2077 EXPORT_SYMBOL(fc_exch_mgr_add);
2080 * fc_exch_mgr_destroy() - Destroy an exchange manager
2081 * @kref: The reference to the EM to be destroyed
2083 static void fc_exch_mgr_destroy(struct kref *kref)
2085 struct fc_exch_mgr *mp = container_of(kref, struct fc_exch_mgr, kref);
2087 mempool_destroy(mp->ep_pool);
2088 free_percpu(mp->pool);
2093 * fc_exch_mgr_del() - Delete an EM from a local port's list
2094 * @ema: The exchange manager anchor identifying the EM to be deleted
2096 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema)
2098 /* remove EM anchor from EM anchors list */
2099 list_del(&ema->ema_list);
2100 kref_put(&ema->mp->kref, fc_exch_mgr_destroy);
2103 EXPORT_SYMBOL(fc_exch_mgr_del);
2106 * fc_exch_mgr_list_clone() - Share all exchange manager objects
2107 * @src: Source lport to clone exchange managers from
2108 * @dst: New lport that takes references to all the exchange managers
2110 int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst)
2112 struct fc_exch_mgr_anchor *ema, *tmp;
2114 list_for_each_entry(ema, &src->ema_list, ema_list) {
2115 if (!fc_exch_mgr_add(dst, ema->mp, ema->match))
2120 list_for_each_entry_safe(ema, tmp, &dst->ema_list, ema_list)
2121 fc_exch_mgr_del(ema);
2126 * fc_exch_mgr_alloc() - Allocate an exchange manager
2127 * @lport: The local port that the new EM will be associated with
2128 * @class: The default FC class for new exchanges
2129 * @min_xid: The minimum XID for exchanges from the new EM
2130 * @max_xid: The maximum XID for exchanges from the new EM
2131 * @match: The match routine for the new EM
2133 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lport,
2134 enum fc_class class,
2135 u16 min_xid, u16 max_xid,
2136 bool (*match)(struct fc_frame *))
2138 struct fc_exch_mgr *mp;
2139 u16 pool_exch_range;
2142 struct fc_exch_pool *pool;
2144 if (max_xid <= min_xid || max_xid == FC_XID_UNKNOWN ||
2145 (min_xid & fc_cpu_mask) != 0) {
2146 FC_LPORT_DBG(lport, "Invalid min_xid 0x:%x and max_xid 0x:%x\n",
2152 * allocate memory for EM
2154 mp = kzalloc(sizeof(struct fc_exch_mgr), GFP_ATOMIC);
2159 /* adjust em exch xid range for offload */
2160 mp->min_xid = min_xid;
2161 mp->max_xid = max_xid;
2163 mp->ep_pool = mempool_create_slab_pool(2, fc_em_cachep);
2168 * Setup per cpu exch pool with entire exchange id range equally
2169 * divided across all cpus. The exch pointers array memory is
2170 * allocated for exch range per pool.
2172 pool_exch_range = (mp->max_xid - mp->min_xid + 1) / (fc_cpu_mask + 1);
2173 mp->pool_max_index = pool_exch_range - 1;
2176 * Allocate and initialize per cpu exch pool
2178 pool_size = sizeof(*pool) + pool_exch_range * sizeof(struct fc_exch *);
2179 mp->pool = __alloc_percpu(pool_size, __alignof__(struct fc_exch_pool));
2182 for_each_possible_cpu(cpu) {
2183 pool = per_cpu_ptr(mp->pool, cpu);
2184 spin_lock_init(&pool->lock);
2185 INIT_LIST_HEAD(&pool->ex_list);
2188 kref_init(&mp->kref);
2189 if (!fc_exch_mgr_add(lport, mp, match)) {
2190 free_percpu(mp->pool);
2195 * Above kref_init() sets mp->kref to 1 and then
2196 * call to fc_exch_mgr_add incremented mp->kref again,
2197 * so adjust that extra increment.
2199 kref_put(&mp->kref, fc_exch_mgr_destroy);
2203 mempool_destroy(mp->ep_pool);
2208 EXPORT_SYMBOL(fc_exch_mgr_alloc);
2211 * fc_exch_mgr_free() - Free all exchange managers on a local port
2212 * @lport: The local port whose EMs are to be freed
2214 void fc_exch_mgr_free(struct fc_lport *lport)
2216 struct fc_exch_mgr_anchor *ema, *next;
2218 flush_workqueue(fc_exch_workqueue);
2219 list_for_each_entry_safe(ema, next, &lport->ema_list, ema_list)
2220 fc_exch_mgr_del(ema);
2222 EXPORT_SYMBOL(fc_exch_mgr_free);
2225 * fc_exch_recv() - Handler for received frames
2226 * @lport: The local port the frame was received on
2227 * @fp: The received frame
2229 void fc_exch_recv(struct fc_lport *lport, struct fc_frame *fp)
2231 struct fc_frame_header *fh = fc_frame_header_get(fp);
2232 struct fc_exch_mgr_anchor *ema;
2233 u32 f_ctl, found = 0;
2237 if (!lport || lport->state == LPORT_ST_DISABLED) {
2238 FC_LPORT_DBG(lport, "Receiving frames for an lport that "
2239 "has not been initialized correctly\n");
2244 f_ctl = ntoh24(fh->fh_f_ctl);
2245 oxid = ntohs(fh->fh_ox_id);
2246 if (f_ctl & FC_FC_EX_CTX) {
2247 list_for_each_entry(ema, &lport->ema_list, ema_list) {
2248 if ((oxid >= ema->mp->min_xid) &&
2249 (oxid <= ema->mp->max_xid)) {
2256 FC_LPORT_DBG(lport, "Received response for out "
2257 "of range oxid:%hx\n", oxid);
2262 ema = list_entry(lport->ema_list.prev, typeof(*ema), ema_list);
2265 * If frame is marked invalid, just drop it.
2267 switch (fr_eof(fp)) {
2269 if (f_ctl & FC_FC_END_SEQ)
2270 skb_trim(fp_skb(fp), fr_len(fp) - FC_FC_FILL(f_ctl));
2273 if (fh->fh_type == FC_TYPE_BLS)
2274 fc_exch_recv_bls(ema->mp, fp);
2275 else if ((f_ctl & (FC_FC_EX_CTX | FC_FC_SEQ_CTX)) ==
2277 fc_exch_recv_seq_resp(ema->mp, fp);
2278 else if (f_ctl & FC_FC_SEQ_CTX)
2279 fc_exch_recv_resp(ema->mp, fp);
2280 else /* no EX_CTX and no SEQ_CTX */
2281 fc_exch_recv_req(lport, ema->mp, fp);
2284 FC_LPORT_DBG(lport, "dropping invalid frame (eof %x)",
2289 EXPORT_SYMBOL(fc_exch_recv);
2292 * fc_exch_init() - Initialize the exchange layer for a local port
2293 * @lport: The local port to initialize the exchange layer for
2295 int fc_exch_init(struct fc_lport *lport)
2297 if (!lport->tt.seq_start_next)
2298 lport->tt.seq_start_next = fc_seq_start_next;
2300 if (!lport->tt.exch_seq_send)
2301 lport->tt.exch_seq_send = fc_exch_seq_send;
2303 if (!lport->tt.seq_send)
2304 lport->tt.seq_send = fc_seq_send;
2306 if (!lport->tt.seq_els_rsp_send)
2307 lport->tt.seq_els_rsp_send = fc_seq_els_rsp_send;
2309 if (!lport->tt.exch_done)
2310 lport->tt.exch_done = fc_exch_done;
2312 if (!lport->tt.exch_mgr_reset)
2313 lport->tt.exch_mgr_reset = fc_exch_mgr_reset;
2315 if (!lport->tt.seq_exch_abort)
2316 lport->tt.seq_exch_abort = fc_seq_exch_abort;
2318 if (!lport->tt.seq_assign)
2319 lport->tt.seq_assign = fc_seq_assign;
2323 EXPORT_SYMBOL(fc_exch_init);
2326 * fc_setup_exch_mgr() - Setup an exchange manager
2328 int fc_setup_exch_mgr()
2330 fc_em_cachep = kmem_cache_create("libfc_em", sizeof(struct fc_exch),
2331 0, SLAB_HWCACHE_ALIGN, NULL);
2336 * Initialize fc_cpu_mask and fc_cpu_order. The
2337 * fc_cpu_mask is set for nr_cpu_ids rounded up
2338 * to order of 2's * power and order is stored
2339 * in fc_cpu_order as this is later required in
2340 * mapping between an exch id and exch array index
2341 * in per cpu exch pool.
2343 * This round up is required to align fc_cpu_mask
2344 * to exchange id's lower bits such that all incoming
2345 * frames of an exchange gets delivered to the same
2346 * cpu on which exchange originated by simple bitwise
2347 * AND operation between fc_cpu_mask and exchange id.
2351 while (fc_cpu_mask < nr_cpu_ids) {
2357 fc_exch_workqueue = create_singlethread_workqueue("fc_exch_workqueue");
2358 if (!fc_exch_workqueue)
2364 * fc_destroy_exch_mgr() - Destroy an exchange manager
2366 void fc_destroy_exch_mgr()
2368 destroy_workqueue(fc_exch_workqueue);
2369 kmem_cache_destroy(fc_em_cachep);