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>
29 #include <linux/export.h>
31 #include <scsi/fc/fc_fc2.h>
33 #include <scsi/libfc.h>
34 #include <scsi/fc_encode.h>
38 u16 fc_cpu_mask; /* cpu mask for possible cpus */
39 EXPORT_SYMBOL(fc_cpu_mask);
40 static u16 fc_cpu_order; /* 2's power to represent total possible cpus */
41 static struct kmem_cache *fc_em_cachep; /* cache for exchanges */
42 static struct workqueue_struct *fc_exch_workqueue;
45 * Structure and function definitions for managing Fibre Channel Exchanges
48 * The three primary structures used here are fc_exch_mgr, fc_exch, and fc_seq.
50 * fc_exch_mgr holds the exchange state for an N port
52 * fc_exch holds state for one exchange and links to its active sequence.
54 * fc_seq holds the state for an individual sequence.
58 * struct fc_exch_pool - Per cpu exchange pool
59 * @next_index: Next possible free exchange index
60 * @total_exches: Total allocated exchanges
61 * @lock: Exch pool lock
62 * @ex_list: List of exchanges
64 * This structure manages per cpu exchanges in array of exchange pointers.
65 * This array is allocated followed by struct fc_exch_pool memory for
66 * assigned range of exchanges to per cpu pool.
70 struct list_head ex_list;
74 /* two cache of free slot in exch array */
77 } ____cacheline_aligned_in_smp;
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.
94 struct fc_exch_pool __percpu *pool;
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;
113 * struct fc_exch_mgr_anchor - primary structure for list of EMs
114 * @ema_list: Exchange Manager Anchor list
115 * @mp: Exchange Manager associated with this anchor
116 * @match: Routine to determine if this anchor's EM should be used
118 * When walking the list of anchors the match routine will be called
119 * for each anchor to determine if that EM should be used. The last
120 * anchor in the list will always match to handle any exchanges not
121 * handled by other EMs. The non-default EMs would be added to the
122 * anchor list by HW that provides offloads.
124 struct fc_exch_mgr_anchor {
125 struct list_head ema_list;
126 struct fc_exch_mgr *mp;
127 bool (*match)(struct fc_frame *);
130 static void fc_exch_rrq(struct fc_exch *);
131 static void fc_seq_ls_acc(struct fc_frame *);
132 static void fc_seq_ls_rjt(struct fc_frame *, enum fc_els_rjt_reason,
133 enum fc_els_rjt_explan);
134 static void fc_exch_els_rec(struct fc_frame *);
135 static void fc_exch_els_rrq(struct fc_frame *);
138 * Internal implementation notes.
140 * The exchange manager is one by default in libfc but LLD may choose
141 * to have one per CPU. The sequence manager is one per exchange manager
142 * and currently never separated.
144 * Section 9.8 in FC-FS-2 specifies: "The SEQ_ID is a one-byte field
145 * assigned by the Sequence Initiator that shall be unique for a specific
146 * D_ID and S_ID pair while the Sequence is open." Note that it isn't
147 * qualified by exchange ID, which one might think it would be.
148 * In practice this limits the number of open sequences and exchanges to 256
149 * per session. For most targets we could treat this limit as per exchange.
151 * The exchange and its sequence are freed when the last sequence is received.
152 * It's possible for the remote port to leave an exchange open without
153 * sending any sequences.
155 * Notes on reference counts:
157 * Exchanges are reference counted and exchange gets freed when the reference
158 * count becomes zero.
161 * Sequences are timed out for E_D_TOV and R_A_TOV.
163 * Sequence event handling:
165 * The following events may occur on initiator sequences:
168 * For now, the whole thing is sent.
170 * This applies only to class F.
171 * The sequence is marked complete.
173 * The upper layer calls fc_exch_done() when done
174 * with exchange and sequence tuple.
175 * RX-inferred completion.
176 * When we receive the next sequence on the same exchange, we can
177 * retire the previous sequence ID. (XXX not implemented).
179 * R_A_TOV frees the sequence ID. If we're waiting for ACK,
180 * E_D_TOV causes abort and calls upper layer response handler
181 * with FC_EX_TIMEOUT error.
187 * The following events may occur on recipient sequences:
190 * Allocate sequence for first frame received.
191 * Hold during receive handler.
192 * Release when final frame received.
193 * Keep status of last N of these for the ELS RES command. XXX TBD.
195 * Deallocate sequence
199 * For now, we neglect conditions where only part of a sequence was
200 * received or transmitted, or where out-of-order receipt is detected.
206 * The EM code run in a per-CPU worker thread.
208 * To protect against concurrency between a worker thread code and timers,
209 * sequence allocation and deallocation must be locked.
210 * - exchange refcnt can be done atomicly without locks.
211 * - sequence allocation must be locked by exch lock.
212 * - If the EM pool lock and ex_lock must be taken at the same time, then the
213 * EM pool lock must be taken before the ex_lock.
217 * opcode names for debugging.
219 static char *fc_exch_rctl_names[] = FC_RCTL_NAMES_INIT;
222 * fc_exch_name_lookup() - Lookup name by opcode
223 * @op: Opcode to be looked up
224 * @table: Opcode/name table
225 * @max_index: Index not to be exceeded
227 * This routine is used to determine a human-readable string identifying
230 static inline const char *fc_exch_name_lookup(unsigned int op, char **table,
231 unsigned int max_index)
233 const char *name = NULL;
243 * fc_exch_rctl_name() - Wrapper routine for fc_exch_name_lookup()
244 * @op: The opcode to be looked up
246 static const char *fc_exch_rctl_name(unsigned int op)
248 return fc_exch_name_lookup(op, fc_exch_rctl_names,
249 ARRAY_SIZE(fc_exch_rctl_names));
253 * fc_exch_hold() - Increment an exchange's reference count
254 * @ep: Echange to be held
256 static inline void fc_exch_hold(struct fc_exch *ep)
258 atomic_inc(&ep->ex_refcnt);
262 * fc_exch_setup_hdr() - Initialize a FC header by initializing some fields
263 * and determine SOF and EOF.
264 * @ep: The exchange to that will use the header
265 * @fp: The frame whose header is to be modified
266 * @f_ctl: F_CTL bits that will be used for the frame header
268 * The fields initialized by this routine are: fh_ox_id, fh_rx_id,
269 * fh_seq_id, fh_seq_cnt and the SOF and EOF.
271 static void fc_exch_setup_hdr(struct fc_exch *ep, struct fc_frame *fp,
274 struct fc_frame_header *fh = fc_frame_header_get(fp);
277 fr_sof(fp) = ep->class;
279 fr_sof(fp) = fc_sof_normal(ep->class);
281 if (f_ctl & FC_FC_END_SEQ) {
282 fr_eof(fp) = FC_EOF_T;
283 if (fc_sof_needs_ack(ep->class))
284 fr_eof(fp) = FC_EOF_N;
287 * The number of fill bytes to make the length a 4-byte
288 * multiple is the low order 2-bits of the f_ctl.
289 * The fill itself will have been cleared by the frame
291 * After this, the length will be even, as expected by
294 fill = fr_len(fp) & 3;
297 /* TODO, this may be a problem with fragmented skb */
298 skb_put(fp_skb(fp), fill);
299 hton24(fh->fh_f_ctl, f_ctl | fill);
302 WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */
303 fr_eof(fp) = FC_EOF_N;
306 /* Initialize remaining fh fields from fc_fill_fc_hdr */
307 fh->fh_ox_id = htons(ep->oxid);
308 fh->fh_rx_id = htons(ep->rxid);
309 fh->fh_seq_id = ep->seq.id;
310 fh->fh_seq_cnt = htons(ep->seq.cnt);
314 * fc_exch_release() - Decrement an exchange's reference count
315 * @ep: Exchange to be released
317 * If the reference count reaches zero and the exchange is complete,
320 static void fc_exch_release(struct fc_exch *ep)
322 struct fc_exch_mgr *mp;
324 if (atomic_dec_and_test(&ep->ex_refcnt)) {
327 ep->destructor(&ep->seq, ep->arg);
328 WARN_ON(!(ep->esb_stat & ESB_ST_COMPLETE));
329 mempool_free(ep, mp->ep_pool);
334 * fc_exch_timer_cancel() - cancel exch timer
335 * @ep: The exchange whose timer to be canceled
337 static inline void fc_exch_timer_cancel(struct fc_exch *ep)
339 if (cancel_delayed_work(&ep->timeout_work)) {
340 FC_EXCH_DBG(ep, "Exchange timer canceled\n");
341 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */
346 * fc_exch_timer_set_locked() - Start a timer for an exchange w/ the
347 * the exchange lock held
348 * @ep: The exchange whose timer will start
349 * @timer_msec: The timeout period
351 * Used for upper level protocols to time out the exchange.
352 * The timer is cancelled when it fires or when the exchange completes.
354 static inline void fc_exch_timer_set_locked(struct fc_exch *ep,
355 unsigned int timer_msec)
357 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
360 FC_EXCH_DBG(ep, "Exchange timer armed : %d msecs\n", timer_msec);
362 if (queue_delayed_work(fc_exch_workqueue, &ep->timeout_work,
363 msecs_to_jiffies(timer_msec)))
364 fc_exch_hold(ep); /* hold for timer */
368 * fc_exch_timer_set() - Lock the exchange and set the timer
369 * @ep: The exchange whose timer will start
370 * @timer_msec: The timeout period
372 static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec)
374 spin_lock_bh(&ep->ex_lock);
375 fc_exch_timer_set_locked(ep, timer_msec);
376 spin_unlock_bh(&ep->ex_lock);
380 * fc_exch_done_locked() - Complete an exchange with the exchange lock held
381 * @ep: The exchange that is complete
383 static int fc_exch_done_locked(struct fc_exch *ep)
388 * We must check for completion in case there are two threads
389 * tyring to complete this. But the rrq code will reuse the
390 * ep, and in that case we only clear the resp and set it as
391 * complete, so it can be reused by the timer to send the rrq.
394 if (ep->state & FC_EX_DONE)
396 ep->esb_stat |= ESB_ST_COMPLETE;
398 if (!(ep->esb_stat & ESB_ST_REC_QUAL)) {
399 ep->state |= FC_EX_DONE;
400 fc_exch_timer_cancel(ep);
407 * fc_exch_ptr_get() - Return an exchange from an exchange pool
408 * @pool: Exchange Pool to get an exchange from
409 * @index: Index of the exchange within the pool
411 * Use the index to get an exchange from within an exchange pool. exches
412 * will point to an array of exchange pointers. The index will select
413 * the exchange within the array.
415 static inline struct fc_exch *fc_exch_ptr_get(struct fc_exch_pool *pool,
418 struct fc_exch **exches = (struct fc_exch **)(pool + 1);
419 return exches[index];
423 * fc_exch_ptr_set() - Assign an exchange to a slot in an exchange pool
424 * @pool: The pool to assign the exchange to
425 * @index: The index in the pool where the exchange will be assigned
426 * @ep: The exchange to assign to the pool
428 static inline void fc_exch_ptr_set(struct fc_exch_pool *pool, u16 index,
431 ((struct fc_exch **)(pool + 1))[index] = ep;
435 * fc_exch_delete() - Delete an exchange
436 * @ep: The exchange to be deleted
438 static void fc_exch_delete(struct fc_exch *ep)
440 struct fc_exch_pool *pool;
444 spin_lock_bh(&pool->lock);
445 WARN_ON(pool->total_exches <= 0);
446 pool->total_exches--;
448 /* update cache of free slot */
449 index = (ep->xid - ep->em->min_xid) >> fc_cpu_order;
450 if (pool->left == FC_XID_UNKNOWN)
452 else if (pool->right == FC_XID_UNKNOWN)
455 pool->next_index = index;
457 fc_exch_ptr_set(pool, index, NULL);
458 list_del(&ep->ex_list);
459 spin_unlock_bh(&pool->lock);
460 fc_exch_release(ep); /* drop hold for exch in mp */
463 static int fc_seq_send_locked(struct fc_lport *lport, struct fc_seq *sp,
467 struct fc_frame_header *fh = fc_frame_header_get(fp);
470 u8 fh_type = fh->fh_type;
472 ep = fc_seq_exch(sp);
473 WARN_ON(!(ep->esb_stat & ESB_ST_SEQ_INIT));
475 f_ctl = ntoh24(fh->fh_f_ctl);
476 fc_exch_setup_hdr(ep, fp, f_ctl);
477 fr_encaps(fp) = ep->encaps;
480 * update sequence count if this frame is carrying
481 * multiple FC frames when sequence offload is enabled
484 if (fr_max_payload(fp))
485 sp->cnt += DIV_ROUND_UP((fr_len(fp) - sizeof(*fh)),
493 error = lport->tt.frame_send(lport, fp);
495 if (fh_type == FC_TYPE_BLS)
499 * Update the exchange and sequence flags,
500 * assuming all frames for the sequence have been sent.
501 * We can only be called to send once for each sequence.
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;
511 * fc_seq_send() - Send a frame using existing sequence/exchange pair
512 * @lport: The local port that the exchange will be sent on
513 * @sp: The sequence to be sent
514 * @fp: The frame to be sent on the exchange
516 static int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp,
521 ep = fc_seq_exch(sp);
522 spin_lock_bh(&ep->ex_lock);
523 error = fc_seq_send_locked(lport, sp, fp);
524 spin_unlock_bh(&ep->ex_lock);
529 * fc_seq_alloc() - Allocate a sequence for a given exchange
530 * @ep: The exchange to allocate a new sequence for
531 * @seq_id: The sequence ID to be used
533 * We don't support multiple originated sequences on the same exchange.
534 * By implication, any previously originated sequence on this exchange
535 * is complete, and we reallocate the same sequence.
537 static struct fc_seq *fc_seq_alloc(struct fc_exch *ep, u8 seq_id)
549 * fc_seq_start_next_locked() - Allocate a new sequence on the same
550 * exchange as the supplied sequence
551 * @sp: The sequence/exchange to get a new sequence for
553 static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp)
555 struct fc_exch *ep = fc_seq_exch(sp);
557 sp = fc_seq_alloc(ep, ep->seq_id++);
558 FC_EXCH_DBG(ep, "f_ctl %6x seq %2x\n",
564 * fc_seq_start_next() - Lock the exchange and get a new sequence
565 * for a given sequence/exchange pair
566 * @sp: The sequence/exchange to get a new exchange for
568 static struct fc_seq *fc_seq_start_next(struct fc_seq *sp)
570 struct fc_exch *ep = fc_seq_exch(sp);
572 spin_lock_bh(&ep->ex_lock);
573 sp = fc_seq_start_next_locked(sp);
574 spin_unlock_bh(&ep->ex_lock);
580 * Set the response handler for the exchange associated with a sequence.
582 static void fc_seq_set_resp(struct fc_seq *sp,
583 void (*resp)(struct fc_seq *, struct fc_frame *,
587 struct fc_exch *ep = fc_seq_exch(sp);
589 spin_lock_bh(&ep->ex_lock);
592 spin_unlock_bh(&ep->ex_lock);
596 * fc_exch_abort_locked() - Abort an exchange
597 * @ep: The exchange to be aborted
598 * @timer_msec: The period of time to wait before aborting
600 * Locking notes: Called with exch lock held
602 * Return value: 0 on success else error code
604 static int fc_exch_abort_locked(struct fc_exch *ep,
605 unsigned int timer_msec)
611 if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL) ||
612 ep->state & (FC_EX_DONE | FC_EX_RST_CLEANUP))
616 * Send the abort on a new sequence if possible.
618 sp = fc_seq_start_next_locked(&ep->seq);
622 ep->esb_stat |= ESB_ST_SEQ_INIT | ESB_ST_ABNORMAL;
624 fc_exch_timer_set_locked(ep, timer_msec);
627 * If not logged into the fabric, don't send ABTS but leave
628 * sequence active until next timeout.
634 * Send an abort for the sequence that timed out.
636 fp = fc_frame_alloc(ep->lp, 0);
638 fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid,
639 FC_TYPE_BLS, FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
640 error = fc_seq_send_locked(ep->lp, sp, fp);
647 * fc_seq_exch_abort() - Abort an exchange and sequence
648 * @req_sp: The sequence to be aborted
649 * @timer_msec: The period of time to wait before aborting
651 * Generally called because of a timeout or an abort from the upper layer.
653 * Return value: 0 on success else error code
655 static int fc_seq_exch_abort(const struct fc_seq *req_sp,
656 unsigned int timer_msec)
661 ep = fc_seq_exch(req_sp);
662 spin_lock_bh(&ep->ex_lock);
663 error = fc_exch_abort_locked(ep, timer_msec);
664 spin_unlock_bh(&ep->ex_lock);
669 * fc_exch_timeout() - Handle exchange timer expiration
670 * @work: The work_struct identifying the exchange that timed out
672 static void fc_exch_timeout(struct work_struct *work)
674 struct fc_exch *ep = container_of(work, struct fc_exch,
676 struct fc_seq *sp = &ep->seq;
677 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
682 FC_EXCH_DBG(ep, "Exchange timed out\n");
684 spin_lock_bh(&ep->ex_lock);
685 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
688 e_stat = ep->esb_stat;
689 if (e_stat & ESB_ST_COMPLETE) {
690 ep->esb_stat = e_stat & ~ESB_ST_REC_QUAL;
691 spin_unlock_bh(&ep->ex_lock);
692 if (e_stat & ESB_ST_REC_QUAL)
699 if (e_stat & ESB_ST_ABNORMAL)
700 rc = fc_exch_done_locked(ep);
701 spin_unlock_bh(&ep->ex_lock);
705 resp(sp, ERR_PTR(-FC_EX_TIMEOUT), arg);
706 fc_seq_exch_abort(sp, 2 * ep->r_a_tov);
710 spin_unlock_bh(&ep->ex_lock);
713 * This release matches the hold taken when the timer was set.
719 * fc_exch_em_alloc() - Allocate an exchange from a specified EM.
720 * @lport: The local port that the exchange is for
721 * @mp: The exchange manager that will allocate the exchange
723 * Returns pointer to allocated fc_exch with exch lock held.
725 static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport,
726 struct fc_exch_mgr *mp)
731 struct fc_exch_pool *pool;
733 /* allocate memory for exchange */
734 ep = mempool_alloc(mp->ep_pool, GFP_ATOMIC);
736 atomic_inc(&mp->stats.no_free_exch);
739 memset(ep, 0, sizeof(*ep));
742 pool = per_cpu_ptr(mp->pool, cpu);
743 spin_lock_bh(&pool->lock);
746 /* peek cache of free slot */
747 if (pool->left != FC_XID_UNKNOWN) {
749 pool->left = FC_XID_UNKNOWN;
752 if (pool->right != FC_XID_UNKNOWN) {
754 pool->right = FC_XID_UNKNOWN;
758 index = pool->next_index;
759 /* allocate new exch from pool */
760 while (fc_exch_ptr_get(pool, index)) {
761 index = index == mp->pool_max_index ? 0 : index + 1;
762 if (index == pool->next_index)
765 pool->next_index = index == mp->pool_max_index ? 0 : index + 1;
767 fc_exch_hold(ep); /* hold for exch in mp */
768 spin_lock_init(&ep->ex_lock);
770 * Hold exch lock for caller to prevent fc_exch_reset()
771 * from releasing exch while fc_exch_alloc() caller is
772 * still working on exch.
774 spin_lock_bh(&ep->ex_lock);
776 fc_exch_ptr_set(pool, index, ep);
777 list_add_tail(&ep->ex_list, &pool->ex_list);
778 fc_seq_alloc(ep, ep->seq_id++);
779 pool->total_exches++;
780 spin_unlock_bh(&pool->lock);
785 ep->oxid = ep->xid = (index << fc_cpu_order | cpu) + mp->min_xid;
789 ep->f_ctl = FC_FC_FIRST_SEQ; /* next seq is first seq */
790 ep->rxid = FC_XID_UNKNOWN;
791 ep->class = mp->class;
792 INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout);
796 spin_unlock_bh(&pool->lock);
797 atomic_inc(&mp->stats.no_free_exch_xid);
798 mempool_free(ep, mp->ep_pool);
803 * fc_exch_alloc() - Allocate an exchange from an EM on a
804 * local port's list of EMs.
805 * @lport: The local port that will own the exchange
806 * @fp: The FC frame that the exchange will be for
808 * This function walks the list of exchange manager(EM)
809 * anchors to select an EM for a new exchange allocation. The
810 * EM is selected when a NULL match function pointer is encountered
811 * or when a call to a match function returns true.
813 static inline struct fc_exch *fc_exch_alloc(struct fc_lport *lport,
816 struct fc_exch_mgr_anchor *ema;
818 list_for_each_entry(ema, &lport->ema_list, ema_list)
819 if (!ema->match || ema->match(fp))
820 return fc_exch_em_alloc(lport, ema->mp);
825 * fc_exch_find() - Lookup and hold an exchange
826 * @mp: The exchange manager to lookup the exchange from
827 * @xid: The XID of the exchange to look up
829 static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid)
831 struct fc_exch_pool *pool;
832 struct fc_exch *ep = NULL;
834 if ((xid >= mp->min_xid) && (xid <= mp->max_xid)) {
835 pool = per_cpu_ptr(mp->pool, xid & fc_cpu_mask);
836 spin_lock_bh(&pool->lock);
837 ep = fc_exch_ptr_get(pool, (xid - mp->min_xid) >> fc_cpu_order);
838 if (ep && ep->xid == xid)
840 spin_unlock_bh(&pool->lock);
847 * fc_exch_done() - Indicate that an exchange/sequence tuple is complete and
848 * the memory allocated for the related objects may be freed.
849 * @sp: The sequence that has completed
851 static void fc_exch_done(struct fc_seq *sp)
853 struct fc_exch *ep = fc_seq_exch(sp);
856 spin_lock_bh(&ep->ex_lock);
857 rc = fc_exch_done_locked(ep);
858 spin_unlock_bh(&ep->ex_lock);
864 * fc_exch_resp() - Allocate a new exchange for a response frame
865 * @lport: The local port that the exchange was for
866 * @mp: The exchange manager to allocate the exchange from
867 * @fp: The response frame
869 * Sets the responder ID in the frame header.
871 static struct fc_exch *fc_exch_resp(struct fc_lport *lport,
872 struct fc_exch_mgr *mp,
876 struct fc_frame_header *fh;
878 ep = fc_exch_alloc(lport, fp);
880 ep->class = fc_frame_class(fp);
883 * Set EX_CTX indicating we're responding on this exchange.
885 ep->f_ctl |= FC_FC_EX_CTX; /* we're responding */
886 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not new */
887 fh = fc_frame_header_get(fp);
888 ep->sid = ntoh24(fh->fh_d_id);
889 ep->did = ntoh24(fh->fh_s_id);
893 * Allocated exchange has placed the XID in the
894 * originator field. Move it to the responder field,
895 * and set the originator XID from the frame.
898 ep->oxid = ntohs(fh->fh_ox_id);
899 ep->esb_stat |= ESB_ST_RESP | ESB_ST_SEQ_INIT;
900 if ((ntoh24(fh->fh_f_ctl) & FC_FC_SEQ_INIT) == 0)
901 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
903 fc_exch_hold(ep); /* hold for caller */
904 spin_unlock_bh(&ep->ex_lock); /* lock from fc_exch_alloc */
910 * fc_seq_lookup_recip() - Find a sequence where the other end
911 * originated the sequence
912 * @lport: The local port that the frame was sent to
913 * @mp: The Exchange Manager to lookup the exchange from
914 * @fp: The frame associated with the sequence we're looking for
916 * If fc_pf_rjt_reason is FC_RJT_NONE then this function will have a hold
917 * on the ep that should be released by the caller.
919 static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport,
920 struct fc_exch_mgr *mp,
923 struct fc_frame_header *fh = fc_frame_header_get(fp);
924 struct fc_exch *ep = NULL;
925 struct fc_seq *sp = NULL;
926 enum fc_pf_rjt_reason reject = FC_RJT_NONE;
930 f_ctl = ntoh24(fh->fh_f_ctl);
931 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != 0);
934 * Lookup or create the exchange if we will be creating the sequence.
936 if (f_ctl & FC_FC_EX_CTX) {
937 xid = ntohs(fh->fh_ox_id); /* we originated exch */
938 ep = fc_exch_find(mp, xid);
940 atomic_inc(&mp->stats.xid_not_found);
941 reject = FC_RJT_OX_ID;
944 if (ep->rxid == FC_XID_UNKNOWN)
945 ep->rxid = ntohs(fh->fh_rx_id);
946 else if (ep->rxid != ntohs(fh->fh_rx_id)) {
947 reject = FC_RJT_OX_ID;
951 xid = ntohs(fh->fh_rx_id); /* we are the responder */
954 * Special case for MDS issuing an ELS TEST with a
956 * XXX take this out once we do the proper reject.
958 if (xid == 0 && fh->fh_r_ctl == FC_RCTL_ELS_REQ &&
959 fc_frame_payload_op(fp) == ELS_TEST) {
960 fh->fh_rx_id = htons(FC_XID_UNKNOWN);
961 xid = FC_XID_UNKNOWN;
965 * new sequence - find the exchange
967 ep = fc_exch_find(mp, xid);
968 if ((f_ctl & FC_FC_FIRST_SEQ) && fc_sof_is_init(fr_sof(fp))) {
970 atomic_inc(&mp->stats.xid_busy);
971 reject = FC_RJT_RX_ID;
974 ep = fc_exch_resp(lport, mp, fp);
976 reject = FC_RJT_EXCH_EST; /* XXX */
979 xid = ep->xid; /* get our XID */
981 atomic_inc(&mp->stats.xid_not_found);
982 reject = FC_RJT_RX_ID; /* XID not found */
988 * At this point, we have the exchange held.
989 * Find or create the sequence.
991 if (fc_sof_is_init(fr_sof(fp))) {
993 sp->ssb_stat |= SSB_ST_RESP;
994 sp->id = fh->fh_seq_id;
997 if (sp->id != fh->fh_seq_id) {
998 atomic_inc(&mp->stats.seq_not_found);
999 if (f_ctl & FC_FC_END_SEQ) {
1001 * Update sequence_id based on incoming last
1002 * frame of sequence exchange. This is needed
1003 * for FC target where DDP has been used
1004 * on target where, stack is indicated only
1005 * about last frame's (payload _header) header.
1006 * Whereas "seq_id" which is part of
1007 * frame_header is allocated by initiator
1008 * which is totally different from "seq_id"
1009 * allocated when XFER_RDY was sent by target.
1010 * To avoid false -ve which results into not
1011 * sending RSP, hence write request on other
1012 * end never finishes.
1014 spin_lock_bh(&ep->ex_lock);
1015 sp->ssb_stat |= SSB_ST_RESP;
1016 sp->id = fh->fh_seq_id;
1017 spin_unlock_bh(&ep->ex_lock);
1019 /* sequence/exch should exist */
1020 reject = FC_RJT_SEQ_ID;
1025 WARN_ON(ep != fc_seq_exch(sp));
1027 if (f_ctl & FC_FC_SEQ_INIT)
1028 ep->esb_stat |= ESB_ST_SEQ_INIT;
1034 fc_exch_done(&ep->seq);
1035 fc_exch_release(ep); /* hold from fc_exch_find/fc_exch_resp */
1040 * fc_seq_lookup_orig() - Find a sequence where this end
1041 * originated the sequence
1042 * @mp: The Exchange Manager to lookup the exchange from
1043 * @fp: The frame associated with the sequence we're looking for
1045 * Does not hold the sequence for the caller.
1047 static struct fc_seq *fc_seq_lookup_orig(struct fc_exch_mgr *mp,
1048 struct fc_frame *fp)
1050 struct fc_frame_header *fh = fc_frame_header_get(fp);
1052 struct fc_seq *sp = NULL;
1056 f_ctl = ntoh24(fh->fh_f_ctl);
1057 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != FC_FC_SEQ_CTX);
1058 xid = ntohs((f_ctl & FC_FC_EX_CTX) ? fh->fh_ox_id : fh->fh_rx_id);
1059 ep = fc_exch_find(mp, xid);
1062 if (ep->seq.id == fh->fh_seq_id) {
1064 * Save the RX_ID if we didn't previously know it.
1067 if ((f_ctl & FC_FC_EX_CTX) != 0 &&
1068 ep->rxid == FC_XID_UNKNOWN) {
1069 ep->rxid = ntohs(fh->fh_rx_id);
1072 fc_exch_release(ep);
1077 * fc_exch_set_addr() - Set the source and destination IDs for an exchange
1078 * @ep: The exchange to set the addresses for
1079 * @orig_id: The originator's ID
1080 * @resp_id: The responder's ID
1082 * Note this must be done before the first sequence of the exchange is sent.
1084 static void fc_exch_set_addr(struct fc_exch *ep,
1085 u32 orig_id, u32 resp_id)
1088 if (ep->esb_stat & ESB_ST_RESP) {
1098 * fc_seq_els_rsp_send() - Send an ELS response using information from
1099 * the existing sequence/exchange.
1100 * @fp: The received frame
1101 * @els_cmd: The ELS command to be sent
1102 * @els_data: The ELS data to be sent
1104 * The received frame is not freed.
1106 static void fc_seq_els_rsp_send(struct fc_frame *fp, enum fc_els_cmd els_cmd,
1107 struct fc_seq_els_data *els_data)
1111 fc_seq_ls_rjt(fp, els_data->reason, els_data->explan);
1117 fc_exch_els_rrq(fp);
1120 fc_exch_els_rec(fp);
1123 FC_LPORT_DBG(fr_dev(fp), "Invalid ELS CMD:%x\n", els_cmd);
1128 * fc_seq_send_last() - Send a sequence that is the last in the exchange
1129 * @sp: The sequence that is to be sent
1130 * @fp: The frame that will be sent on the sequence
1131 * @rctl: The R_CTL information to be sent
1132 * @fh_type: The frame header type
1134 static void fc_seq_send_last(struct fc_seq *sp, struct fc_frame *fp,
1135 enum fc_rctl rctl, enum fc_fh_type fh_type)
1138 struct fc_exch *ep = fc_seq_exch(sp);
1140 f_ctl = FC_FC_LAST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT;
1142 fc_fill_fc_hdr(fp, rctl, ep->did, ep->sid, fh_type, f_ctl, 0);
1143 fc_seq_send_locked(ep->lp, sp, fp);
1147 * fc_seq_send_ack() - Send an acknowledgement that we've received a frame
1148 * @sp: The sequence to send the ACK on
1149 * @rx_fp: The received frame that is being acknoledged
1151 * Send ACK_1 (or equiv.) indicating we received something.
1153 static void fc_seq_send_ack(struct fc_seq *sp, const struct fc_frame *rx_fp)
1155 struct fc_frame *fp;
1156 struct fc_frame_header *rx_fh;
1157 struct fc_frame_header *fh;
1158 struct fc_exch *ep = fc_seq_exch(sp);
1159 struct fc_lport *lport = ep->lp;
1163 * Don't send ACKs for class 3.
1165 if (fc_sof_needs_ack(fr_sof(rx_fp))) {
1166 fp = fc_frame_alloc(lport, 0);
1170 fh = fc_frame_header_get(fp);
1171 fh->fh_r_ctl = FC_RCTL_ACK_1;
1172 fh->fh_type = FC_TYPE_BLS;
1175 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
1176 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
1177 * Bits 9-8 are meaningful (retransmitted or unidirectional).
1178 * Last ACK uses bits 7-6 (continue sequence),
1179 * bits 5-4 are meaningful (what kind of ACK to use).
1181 rx_fh = fc_frame_header_get(rx_fp);
1182 f_ctl = ntoh24(rx_fh->fh_f_ctl);
1183 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
1184 FC_FC_FIRST_SEQ | FC_FC_LAST_SEQ |
1185 FC_FC_END_SEQ | FC_FC_END_CONN | FC_FC_SEQ_INIT |
1186 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
1187 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
1188 hton24(fh->fh_f_ctl, f_ctl);
1190 fc_exch_setup_hdr(ep, fp, f_ctl);
1191 fh->fh_seq_id = rx_fh->fh_seq_id;
1192 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
1193 fh->fh_parm_offset = htonl(1); /* ack single frame */
1195 fr_sof(fp) = fr_sof(rx_fp);
1196 if (f_ctl & FC_FC_END_SEQ)
1197 fr_eof(fp) = FC_EOF_T;
1199 fr_eof(fp) = FC_EOF_N;
1201 lport->tt.frame_send(lport, fp);
1206 * fc_exch_send_ba_rjt() - Send BLS Reject
1207 * @rx_fp: The frame being rejected
1208 * @reason: The reason the frame is being rejected
1209 * @explan: The explanation for the rejection
1211 * This is for rejecting BA_ABTS only.
1213 static void fc_exch_send_ba_rjt(struct fc_frame *rx_fp,
1214 enum fc_ba_rjt_reason reason,
1215 enum fc_ba_rjt_explan explan)
1217 struct fc_frame *fp;
1218 struct fc_frame_header *rx_fh;
1219 struct fc_frame_header *fh;
1220 struct fc_ba_rjt *rp;
1221 struct fc_lport *lport;
1224 lport = fr_dev(rx_fp);
1225 fp = fc_frame_alloc(lport, sizeof(*rp));
1228 fh = fc_frame_header_get(fp);
1229 rx_fh = fc_frame_header_get(rx_fp);
1231 memset(fh, 0, sizeof(*fh) + sizeof(*rp));
1233 rp = fc_frame_payload_get(fp, sizeof(*rp));
1234 rp->br_reason = reason;
1235 rp->br_explan = explan;
1238 * seq_id, cs_ctl, df_ctl and param/offset are zero.
1240 memcpy(fh->fh_s_id, rx_fh->fh_d_id, 3);
1241 memcpy(fh->fh_d_id, rx_fh->fh_s_id, 3);
1242 fh->fh_ox_id = rx_fh->fh_ox_id;
1243 fh->fh_rx_id = rx_fh->fh_rx_id;
1244 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
1245 fh->fh_r_ctl = FC_RCTL_BA_RJT;
1246 fh->fh_type = FC_TYPE_BLS;
1249 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
1250 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
1251 * Bits 9-8 are meaningful (retransmitted or unidirectional).
1252 * Last ACK uses bits 7-6 (continue sequence),
1253 * bits 5-4 are meaningful (what kind of ACK to use).
1254 * Always set LAST_SEQ, END_SEQ.
1256 f_ctl = ntoh24(rx_fh->fh_f_ctl);
1257 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
1258 FC_FC_END_CONN | FC_FC_SEQ_INIT |
1259 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
1260 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
1261 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
1262 f_ctl &= ~FC_FC_FIRST_SEQ;
1263 hton24(fh->fh_f_ctl, f_ctl);
1265 fr_sof(fp) = fc_sof_class(fr_sof(rx_fp));
1266 fr_eof(fp) = FC_EOF_T;
1267 if (fc_sof_needs_ack(fr_sof(fp)))
1268 fr_eof(fp) = FC_EOF_N;
1270 lport->tt.frame_send(lport, fp);
1274 * fc_exch_recv_abts() - Handle an incoming ABTS
1275 * @ep: The exchange the abort was on
1276 * @rx_fp: The ABTS frame
1278 * This would be for target mode usually, but could be due to lost
1279 * FCP transfer ready, confirm or RRQ. We always handle this as an
1280 * exchange abort, ignoring the parameter.
1282 static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp)
1284 struct fc_frame *fp;
1285 struct fc_ba_acc *ap;
1286 struct fc_frame_header *fh;
1291 spin_lock_bh(&ep->ex_lock);
1292 if (ep->esb_stat & ESB_ST_COMPLETE) {
1293 spin_unlock_bh(&ep->ex_lock);
1296 if (!(ep->esb_stat & ESB_ST_REC_QUAL))
1297 fc_exch_hold(ep); /* hold for REC_QUAL */
1298 ep->esb_stat |= ESB_ST_ABNORMAL | ESB_ST_REC_QUAL;
1299 fc_exch_timer_set_locked(ep, ep->r_a_tov);
1301 fp = fc_frame_alloc(ep->lp, sizeof(*ap));
1303 spin_unlock_bh(&ep->ex_lock);
1306 fh = fc_frame_header_get(fp);
1307 ap = fc_frame_payload_get(fp, sizeof(*ap));
1308 memset(ap, 0, sizeof(*ap));
1310 ap->ba_high_seq_cnt = htons(0xffff);
1311 if (sp->ssb_stat & SSB_ST_RESP) {
1312 ap->ba_seq_id = sp->id;
1313 ap->ba_seq_id_val = FC_BA_SEQ_ID_VAL;
1314 ap->ba_high_seq_cnt = fh->fh_seq_cnt;
1315 ap->ba_low_seq_cnt = htons(sp->cnt);
1317 sp = fc_seq_start_next_locked(sp);
1318 fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS);
1319 spin_unlock_bh(&ep->ex_lock);
1320 fc_frame_free(rx_fp);
1324 fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID);
1326 fc_frame_free(rx_fp);
1330 * fc_seq_assign() - Assign exchange and sequence for incoming request
1331 * @lport: The local port that received the request
1332 * @fp: The request frame
1334 * On success, the sequence pointer will be returned and also in fr_seq(@fp).
1335 * A reference will be held on the exchange/sequence for the caller, which
1336 * must call fc_seq_release().
1338 static struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp)
1340 struct fc_exch_mgr_anchor *ema;
1342 WARN_ON(lport != fr_dev(fp));
1343 WARN_ON(fr_seq(fp));
1346 list_for_each_entry(ema, &lport->ema_list, ema_list)
1347 if ((!ema->match || ema->match(fp)) &&
1348 fc_seq_lookup_recip(lport, ema->mp, fp) == FC_RJT_NONE)
1354 * fc_seq_release() - Release the hold
1355 * @sp: The sequence.
1357 static void fc_seq_release(struct fc_seq *sp)
1359 fc_exch_release(fc_seq_exch(sp));
1363 * fc_exch_recv_req() - Handler for an incoming request
1364 * @lport: The local port that received the request
1365 * @mp: The EM that the exchange is on
1366 * @fp: The request frame
1368 * This is used when the other end is originating the exchange
1371 static void fc_exch_recv_req(struct fc_lport *lport, struct fc_exch_mgr *mp,
1372 struct fc_frame *fp)
1374 struct fc_frame_header *fh = fc_frame_header_get(fp);
1375 struct fc_seq *sp = NULL;
1376 struct fc_exch *ep = NULL;
1377 enum fc_pf_rjt_reason reject;
1379 /* We can have the wrong fc_lport at this point with NPIV, which is a
1380 * problem now that we know a new exchange needs to be allocated
1382 lport = fc_vport_id_lookup(lport, ntoh24(fh->fh_d_id));
1389 BUG_ON(fr_seq(fp)); /* XXX remove later */
1392 * If the RX_ID is 0xffff, don't allocate an exchange.
1393 * The upper-level protocol may request one later, if needed.
1395 if (fh->fh_rx_id == htons(FC_XID_UNKNOWN))
1396 return lport->tt.lport_recv(lport, fp);
1398 reject = fc_seq_lookup_recip(lport, mp, fp);
1399 if (reject == FC_RJT_NONE) {
1400 sp = fr_seq(fp); /* sequence will be held */
1401 ep = fc_seq_exch(sp);
1402 fc_seq_send_ack(sp, fp);
1403 ep->encaps = fr_encaps(fp);
1406 * Call the receive function.
1408 * The receive function may allocate a new sequence
1409 * over the old one, so we shouldn't change the
1410 * sequence after this.
1412 * The frame will be freed by the receive function.
1413 * If new exch resp handler is valid then call that
1417 ep->resp(sp, fp, ep->arg);
1419 lport->tt.lport_recv(lport, fp);
1420 fc_exch_release(ep); /* release from lookup */
1422 FC_LPORT_DBG(lport, "exch/seq lookup failed: reject %x\n",
1429 * fc_exch_recv_seq_resp() - Handler for an incoming response where the other
1430 * end is the originator of the sequence that is a
1431 * response to our initial exchange
1432 * @mp: The EM that the exchange is on
1433 * @fp: The response frame
1435 static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1437 struct fc_frame_header *fh = fc_frame_header_get(fp);
1442 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1446 ep = fc_exch_find(mp, ntohs(fh->fh_ox_id));
1448 atomic_inc(&mp->stats.xid_not_found);
1451 if (ep->esb_stat & ESB_ST_COMPLETE) {
1452 atomic_inc(&mp->stats.xid_not_found);
1455 if (ep->rxid == FC_XID_UNKNOWN)
1456 ep->rxid = ntohs(fh->fh_rx_id);
1457 if (ep->sid != 0 && ep->sid != ntoh24(fh->fh_d_id)) {
1458 atomic_inc(&mp->stats.xid_not_found);
1461 if (ep->did != ntoh24(fh->fh_s_id) &&
1462 ep->did != FC_FID_FLOGI) {
1463 atomic_inc(&mp->stats.xid_not_found);
1468 if (fc_sof_is_init(sof)) {
1469 sp->ssb_stat |= SSB_ST_RESP;
1470 sp->id = fh->fh_seq_id;
1471 } else if (sp->id != fh->fh_seq_id) {
1472 atomic_inc(&mp->stats.seq_not_found);
1476 f_ctl = ntoh24(fh->fh_f_ctl);
1478 if (f_ctl & FC_FC_SEQ_INIT)
1479 ep->esb_stat |= ESB_ST_SEQ_INIT;
1481 if (fc_sof_needs_ack(sof))
1482 fc_seq_send_ack(sp, fp);
1484 ex_resp_arg = ep->arg;
1486 if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T &&
1487 (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) ==
1488 (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) {
1489 spin_lock_bh(&ep->ex_lock);
1491 rc = fc_exch_done_locked(ep);
1492 WARN_ON(fc_seq_exch(sp) != ep);
1493 spin_unlock_bh(&ep->ex_lock);
1499 * Call the receive function.
1500 * The sequence is held (has a refcnt) for us,
1501 * but not for the receive function.
1503 * The receive function may allocate a new sequence
1504 * over the old one, so we shouldn't change the
1505 * sequence after this.
1507 * The frame will be freed by the receive function.
1508 * If new exch resp handler is valid then call that
1512 resp(sp, fp, ex_resp_arg);
1515 fc_exch_release(ep);
1518 fc_exch_release(ep);
1524 * fc_exch_recv_resp() - Handler for a sequence where other end is
1525 * responding to our sequence
1526 * @mp: The EM that the exchange is on
1527 * @fp: The response frame
1529 static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1533 sp = fc_seq_lookup_orig(mp, fp); /* doesn't hold sequence */
1536 atomic_inc(&mp->stats.xid_not_found);
1538 atomic_inc(&mp->stats.non_bls_resp);
1544 * fc_exch_abts_resp() - Handler for a response to an ABT
1545 * @ep: The exchange that the frame is on
1546 * @fp: The response frame
1548 * This response would be to an ABTS cancelling an exchange or sequence.
1549 * The response can be either BA_ACC or BA_RJT
1551 static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp)
1553 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1555 struct fc_frame_header *fh;
1556 struct fc_ba_acc *ap;
1560 int rc = 1, has_rec = 0;
1562 fh = fc_frame_header_get(fp);
1563 FC_EXCH_DBG(ep, "exch: BLS rctl %x - %s\n", fh->fh_r_ctl,
1564 fc_exch_rctl_name(fh->fh_r_ctl));
1566 if (cancel_delayed_work_sync(&ep->timeout_work)) {
1567 FC_EXCH_DBG(ep, "Exchange timer canceled due to ABTS response\n");
1568 fc_exch_release(ep); /* release from pending timer hold */
1571 spin_lock_bh(&ep->ex_lock);
1572 switch (fh->fh_r_ctl) {
1573 case FC_RCTL_BA_ACC:
1574 ap = fc_frame_payload_get(fp, sizeof(*ap));
1579 * Decide whether to establish a Recovery Qualifier.
1580 * We do this if there is a non-empty SEQ_CNT range and
1581 * SEQ_ID is the same as the one we aborted.
1583 low = ntohs(ap->ba_low_seq_cnt);
1584 high = ntohs(ap->ba_high_seq_cnt);
1585 if ((ep->esb_stat & ESB_ST_REC_QUAL) == 0 &&
1586 (ap->ba_seq_id_val != FC_BA_SEQ_ID_VAL ||
1587 ap->ba_seq_id == ep->seq_id) && low != high) {
1588 ep->esb_stat |= ESB_ST_REC_QUAL;
1589 fc_exch_hold(ep); /* hold for recovery qualifier */
1593 case FC_RCTL_BA_RJT:
1600 ex_resp_arg = ep->arg;
1602 /* do we need to do some other checks here. Can we reuse more of
1603 * fc_exch_recv_seq_resp
1607 * do we want to check END_SEQ as well as LAST_SEQ here?
1609 if (ep->fh_type != FC_TYPE_FCP &&
1610 ntoh24(fh->fh_f_ctl) & FC_FC_LAST_SEQ)
1611 rc = fc_exch_done_locked(ep);
1612 spin_unlock_bh(&ep->ex_lock);
1617 resp(sp, fp, ex_resp_arg);
1622 fc_exch_timer_set(ep, ep->r_a_tov);
1627 * fc_exch_recv_bls() - Handler for a BLS sequence
1628 * @mp: The EM that the exchange is on
1629 * @fp: The request frame
1631 * The BLS frame is always a sequence initiated by the remote side.
1632 * We may be either the originator or recipient of the exchange.
1634 static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp)
1636 struct fc_frame_header *fh;
1640 fh = fc_frame_header_get(fp);
1641 f_ctl = ntoh24(fh->fh_f_ctl);
1644 ep = fc_exch_find(mp, (f_ctl & FC_FC_EX_CTX) ?
1645 ntohs(fh->fh_ox_id) : ntohs(fh->fh_rx_id));
1646 if (ep && (f_ctl & FC_FC_SEQ_INIT)) {
1647 spin_lock_bh(&ep->ex_lock);
1648 ep->esb_stat |= ESB_ST_SEQ_INIT;
1649 spin_unlock_bh(&ep->ex_lock);
1651 if (f_ctl & FC_FC_SEQ_CTX) {
1653 * A response to a sequence we initiated.
1654 * This should only be ACKs for class 2 or F.
1656 switch (fh->fh_r_ctl) {
1662 FC_EXCH_DBG(ep, "BLS rctl %x - %s received",
1664 fc_exch_rctl_name(fh->fh_r_ctl));
1669 switch (fh->fh_r_ctl) {
1670 case FC_RCTL_BA_RJT:
1671 case FC_RCTL_BA_ACC:
1673 fc_exch_abts_resp(ep, fp);
1677 case FC_RCTL_BA_ABTS:
1678 fc_exch_recv_abts(ep, fp);
1680 default: /* ignore junk */
1686 fc_exch_release(ep); /* release hold taken by fc_exch_find */
1690 * fc_seq_ls_acc() - Accept sequence with LS_ACC
1691 * @rx_fp: The received frame, not freed here.
1693 * If this fails due to allocation or transmit congestion, assume the
1694 * originator will repeat the sequence.
1696 static void fc_seq_ls_acc(struct fc_frame *rx_fp)
1698 struct fc_lport *lport;
1699 struct fc_els_ls_acc *acc;
1700 struct fc_frame *fp;
1702 lport = fr_dev(rx_fp);
1703 fp = fc_frame_alloc(lport, sizeof(*acc));
1706 acc = fc_frame_payload_get(fp, sizeof(*acc));
1707 memset(acc, 0, sizeof(*acc));
1708 acc->la_cmd = ELS_LS_ACC;
1709 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
1710 lport->tt.frame_send(lport, fp);
1714 * fc_seq_ls_rjt() - Reject a sequence with ELS LS_RJT
1715 * @rx_fp: The received frame, not freed here.
1716 * @reason: The reason the sequence is being rejected
1717 * @explan: The explanation for the rejection
1719 * If this fails due to allocation or transmit congestion, assume the
1720 * originator will repeat the sequence.
1722 static void fc_seq_ls_rjt(struct fc_frame *rx_fp, enum fc_els_rjt_reason reason,
1723 enum fc_els_rjt_explan explan)
1725 struct fc_lport *lport;
1726 struct fc_els_ls_rjt *rjt;
1727 struct fc_frame *fp;
1729 lport = fr_dev(rx_fp);
1730 fp = fc_frame_alloc(lport, sizeof(*rjt));
1733 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1734 memset(rjt, 0, sizeof(*rjt));
1735 rjt->er_cmd = ELS_LS_RJT;
1736 rjt->er_reason = reason;
1737 rjt->er_explan = explan;
1738 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
1739 lport->tt.frame_send(lport, fp);
1743 * fc_exch_reset() - Reset an exchange
1744 * @ep: The exchange to be reset
1746 static void fc_exch_reset(struct fc_exch *ep)
1749 void (*resp)(struct fc_seq *, struct fc_frame *, void *);
1753 spin_lock_bh(&ep->ex_lock);
1754 fc_exch_abort_locked(ep, 0);
1755 ep->state |= FC_EX_RST_CLEANUP;
1756 fc_exch_timer_cancel(ep);
1759 if (ep->esb_stat & ESB_ST_REC_QUAL)
1760 atomic_dec(&ep->ex_refcnt); /* drop hold for rec_qual */
1761 ep->esb_stat &= ~ESB_ST_REC_QUAL;
1764 rc = fc_exch_done_locked(ep);
1765 spin_unlock_bh(&ep->ex_lock);
1770 resp(sp, ERR_PTR(-FC_EX_CLOSED), arg);
1774 * fc_exch_pool_reset() - Reset a per cpu exchange pool
1775 * @lport: The local port that the exchange pool is on
1776 * @pool: The exchange pool to be reset
1777 * @sid: The source ID
1778 * @did: The destination ID
1780 * Resets a per cpu exches pool, releasing all of its sequences
1781 * and exchanges. If sid is non-zero then reset only exchanges
1782 * we sourced from the local port's FID. If did is non-zero then
1783 * only reset exchanges destined for the local port's FID.
1785 static void fc_exch_pool_reset(struct fc_lport *lport,
1786 struct fc_exch_pool *pool,
1790 struct fc_exch *next;
1792 spin_lock_bh(&pool->lock);
1794 list_for_each_entry_safe(ep, next, &pool->ex_list, ex_list) {
1795 if ((lport == ep->lp) &&
1796 (sid == 0 || sid == ep->sid) &&
1797 (did == 0 || did == ep->did)) {
1799 spin_unlock_bh(&pool->lock);
1803 fc_exch_release(ep);
1804 spin_lock_bh(&pool->lock);
1807 * must restart loop incase while lock
1808 * was down multiple eps were released.
1813 pool->next_index = 0;
1814 pool->left = FC_XID_UNKNOWN;
1815 pool->right = FC_XID_UNKNOWN;
1816 spin_unlock_bh(&pool->lock);
1820 * fc_exch_mgr_reset() - Reset all EMs of a local port
1821 * @lport: The local port whose EMs are to be reset
1822 * @sid: The source ID
1823 * @did: The destination ID
1825 * Reset all EMs associated with a given local port. Release all
1826 * sequences and exchanges. If sid is non-zero then reset only the
1827 * exchanges sent from the local port's FID. If did is non-zero then
1828 * reset only exchanges destined for the local port's FID.
1830 void fc_exch_mgr_reset(struct fc_lport *lport, u32 sid, u32 did)
1832 struct fc_exch_mgr_anchor *ema;
1835 list_for_each_entry(ema, &lport->ema_list, ema_list) {
1836 for_each_possible_cpu(cpu)
1837 fc_exch_pool_reset(lport,
1838 per_cpu_ptr(ema->mp->pool, cpu),
1842 EXPORT_SYMBOL(fc_exch_mgr_reset);
1845 * fc_exch_lookup() - find an exchange
1846 * @lport: The local port
1847 * @xid: The exchange ID
1849 * Returns exchange pointer with hold for caller, or NULL if not found.
1851 static struct fc_exch *fc_exch_lookup(struct fc_lport *lport, u32 xid)
1853 struct fc_exch_mgr_anchor *ema;
1855 list_for_each_entry(ema, &lport->ema_list, ema_list)
1856 if (ema->mp->min_xid <= xid && xid <= ema->mp->max_xid)
1857 return fc_exch_find(ema->mp, xid);
1862 * fc_exch_els_rec() - Handler for ELS REC (Read Exchange Concise) requests
1863 * @rfp: The REC frame, not freed here.
1865 * Note that the requesting port may be different than the S_ID in the request.
1867 static void fc_exch_els_rec(struct fc_frame *rfp)
1869 struct fc_lport *lport;
1870 struct fc_frame *fp;
1872 struct fc_els_rec *rp;
1873 struct fc_els_rec_acc *acc;
1874 enum fc_els_rjt_reason reason = ELS_RJT_LOGIC;
1875 enum fc_els_rjt_explan explan;
1880 lport = fr_dev(rfp);
1881 rp = fc_frame_payload_get(rfp, sizeof(*rp));
1882 explan = ELS_EXPL_INV_LEN;
1885 sid = ntoh24(rp->rec_s_id);
1886 rxid = ntohs(rp->rec_rx_id);
1887 oxid = ntohs(rp->rec_ox_id);
1889 ep = fc_exch_lookup(lport,
1890 sid == fc_host_port_id(lport->host) ? oxid : rxid);
1891 explan = ELS_EXPL_OXID_RXID;
1894 if (ep->oid != sid || oxid != ep->oxid)
1896 if (rxid != FC_XID_UNKNOWN && rxid != ep->rxid)
1898 fp = fc_frame_alloc(lport, sizeof(*acc));
1902 acc = fc_frame_payload_get(fp, sizeof(*acc));
1903 memset(acc, 0, sizeof(*acc));
1904 acc->reca_cmd = ELS_LS_ACC;
1905 acc->reca_ox_id = rp->rec_ox_id;
1906 memcpy(acc->reca_ofid, rp->rec_s_id, 3);
1907 acc->reca_rx_id = htons(ep->rxid);
1908 if (ep->sid == ep->oid)
1909 hton24(acc->reca_rfid, ep->did);
1911 hton24(acc->reca_rfid, ep->sid);
1912 acc->reca_fc4value = htonl(ep->seq.rec_data);
1913 acc->reca_e_stat = htonl(ep->esb_stat & (ESB_ST_RESP |
1916 fc_fill_reply_hdr(fp, rfp, FC_RCTL_ELS_REP, 0);
1917 lport->tt.frame_send(lport, fp);
1919 fc_exch_release(ep);
1923 fc_exch_release(ep);
1925 fc_seq_ls_rjt(rfp, reason, explan);
1929 * fc_exch_rrq_resp() - Handler for RRQ responses
1930 * @sp: The sequence that the RRQ is on
1931 * @fp: The RRQ frame
1932 * @arg: The exchange that the RRQ is on
1934 * TODO: fix error handler.
1936 static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg)
1938 struct fc_exch *aborted_ep = arg;
1942 int err = PTR_ERR(fp);
1944 if (err == -FC_EX_CLOSED || err == -FC_EX_TIMEOUT)
1946 FC_EXCH_DBG(aborted_ep, "Cannot process RRQ, "
1947 "frame error %d\n", err);
1951 op = fc_frame_payload_op(fp);
1956 FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ");
1961 FC_EXCH_DBG(aborted_ep, "unexpected response op %x "
1967 fc_exch_done(&aborted_ep->seq);
1968 /* drop hold for rec qual */
1969 fc_exch_release(aborted_ep);
1974 * fc_exch_seq_send() - Send a frame using a new exchange and sequence
1975 * @lport: The local port to send the frame on
1976 * @fp: The frame to be sent
1977 * @resp: The response handler for this request
1978 * @destructor: The destructor for the exchange
1979 * @arg: The argument to be passed to the response handler
1980 * @timer_msec: The timeout period for the exchange
1982 * The frame pointer with some of the header's fields must be
1983 * filled before calling this routine, those fields are:
1990 * - parameter or relative offset
1992 static struct fc_seq *fc_exch_seq_send(struct fc_lport *lport,
1993 struct fc_frame *fp,
1994 void (*resp)(struct fc_seq *,
1995 struct fc_frame *fp,
1997 void (*destructor)(struct fc_seq *,
1999 void *arg, u32 timer_msec)
2002 struct fc_seq *sp = NULL;
2003 struct fc_frame_header *fh;
2004 struct fc_fcp_pkt *fsp = NULL;
2007 ep = fc_exch_alloc(lport, fp);
2012 ep->esb_stat |= ESB_ST_SEQ_INIT;
2013 fh = fc_frame_header_get(fp);
2014 fc_exch_set_addr(ep, ntoh24(fh->fh_s_id), ntoh24(fh->fh_d_id));
2016 ep->destructor = destructor;
2018 ep->r_a_tov = FC_DEF_R_A_TOV;
2022 ep->fh_type = fh->fh_type; /* save for possbile timeout handling */
2023 ep->f_ctl = ntoh24(fh->fh_f_ctl);
2024 fc_exch_setup_hdr(ep, fp, ep->f_ctl);
2027 if (ep->xid <= lport->lro_xid && fh->fh_r_ctl == FC_RCTL_DD_UNSOL_CMD) {
2029 fc_fcp_ddp_setup(fr_fsp(fp), ep->xid);
2032 if (unlikely(lport->tt.frame_send(lport, fp)))
2036 fc_exch_timer_set_locked(ep, timer_msec);
2037 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not first seq */
2039 if (ep->f_ctl & FC_FC_SEQ_INIT)
2040 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
2041 spin_unlock_bh(&ep->ex_lock);
2045 fc_fcp_ddp_done(fsp);
2046 rc = fc_exch_done_locked(ep);
2047 spin_unlock_bh(&ep->ex_lock);
2054 * fc_exch_rrq() - Send an ELS RRQ (Reinstate Recovery Qualifier) command
2055 * @ep: The exchange to send the RRQ on
2057 * This tells the remote port to stop blocking the use of
2058 * the exchange and the seq_cnt range.
2060 static void fc_exch_rrq(struct fc_exch *ep)
2062 struct fc_lport *lport;
2063 struct fc_els_rrq *rrq;
2064 struct fc_frame *fp;
2069 fp = fc_frame_alloc(lport, sizeof(*rrq));
2073 rrq = fc_frame_payload_get(fp, sizeof(*rrq));
2074 memset(rrq, 0, sizeof(*rrq));
2075 rrq->rrq_cmd = ELS_RRQ;
2076 hton24(rrq->rrq_s_id, ep->sid);
2077 rrq->rrq_ox_id = htons(ep->oxid);
2078 rrq->rrq_rx_id = htons(ep->rxid);
2081 if (ep->esb_stat & ESB_ST_RESP)
2084 fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, did,
2085 lport->port_id, FC_TYPE_ELS,
2086 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
2088 if (fc_exch_seq_send(lport, fp, fc_exch_rrq_resp, NULL, ep,
2093 spin_lock_bh(&ep->ex_lock);
2094 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) {
2095 spin_unlock_bh(&ep->ex_lock);
2096 /* drop hold for rec qual */
2097 fc_exch_release(ep);
2100 ep->esb_stat |= ESB_ST_REC_QUAL;
2101 fc_exch_timer_set_locked(ep, ep->r_a_tov);
2102 spin_unlock_bh(&ep->ex_lock);
2106 * fc_exch_els_rrq() - Handler for ELS RRQ (Reset Recovery Qualifier) requests
2107 * @fp: The RRQ frame, not freed here.
2109 static void fc_exch_els_rrq(struct fc_frame *fp)
2111 struct fc_lport *lport;
2112 struct fc_exch *ep = NULL; /* request or subject exchange */
2113 struct fc_els_rrq *rp;
2116 enum fc_els_rjt_explan explan;
2119 rp = fc_frame_payload_get(fp, sizeof(*rp));
2120 explan = ELS_EXPL_INV_LEN;
2125 * lookup subject exchange.
2127 sid = ntoh24(rp->rrq_s_id); /* subject source */
2128 xid = fc_host_port_id(lport->host) == sid ?
2129 ntohs(rp->rrq_ox_id) : ntohs(rp->rrq_rx_id);
2130 ep = fc_exch_lookup(lport, xid);
2131 explan = ELS_EXPL_OXID_RXID;
2134 spin_lock_bh(&ep->ex_lock);
2135 if (ep->oxid != ntohs(rp->rrq_ox_id))
2137 if (ep->rxid != ntohs(rp->rrq_rx_id) &&
2138 ep->rxid != FC_XID_UNKNOWN)
2140 explan = ELS_EXPL_SID;
2145 * Clear Recovery Qualifier state, and cancel timer if complete.
2147 if (ep->esb_stat & ESB_ST_REC_QUAL) {
2148 ep->esb_stat &= ~ESB_ST_REC_QUAL;
2149 atomic_dec(&ep->ex_refcnt); /* drop hold for rec qual */
2151 if (ep->esb_stat & ESB_ST_COMPLETE)
2152 fc_exch_timer_cancel(ep);
2154 spin_unlock_bh(&ep->ex_lock);
2163 spin_unlock_bh(&ep->ex_lock);
2165 fc_seq_ls_rjt(fp, ELS_RJT_LOGIC, explan);
2168 fc_exch_release(ep); /* drop hold from fc_exch_find */
2172 * fc_exch_update_stats() - update exches stats to lport
2173 * @lport: The local port to update exchange manager stats
2175 void fc_exch_update_stats(struct fc_lport *lport)
2177 struct fc_host_statistics *st;
2178 struct fc_exch_mgr_anchor *ema;
2179 struct fc_exch_mgr *mp;
2181 st = &lport->host_stats;
2183 list_for_each_entry(ema, &lport->ema_list, ema_list) {
2185 st->fc_no_free_exch += atomic_read(&mp->stats.no_free_exch);
2186 st->fc_no_free_exch_xid +=
2187 atomic_read(&mp->stats.no_free_exch_xid);
2188 st->fc_xid_not_found += atomic_read(&mp->stats.xid_not_found);
2189 st->fc_xid_busy += atomic_read(&mp->stats.xid_busy);
2190 st->fc_seq_not_found += atomic_read(&mp->stats.seq_not_found);
2191 st->fc_non_bls_resp += atomic_read(&mp->stats.non_bls_resp);
2194 EXPORT_SYMBOL(fc_exch_update_stats);
2197 * fc_exch_mgr_add() - Add an exchange manager to a local port's list of EMs
2198 * @lport: The local port to add the exchange manager to
2199 * @mp: The exchange manager to be added to the local port
2200 * @match: The match routine that indicates when this EM should be used
2202 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport,
2203 struct fc_exch_mgr *mp,
2204 bool (*match)(struct fc_frame *))
2206 struct fc_exch_mgr_anchor *ema;
2208 ema = kmalloc(sizeof(*ema), GFP_ATOMIC);
2214 /* add EM anchor to EM anchors list */
2215 list_add_tail(&ema->ema_list, &lport->ema_list);
2216 kref_get(&mp->kref);
2219 EXPORT_SYMBOL(fc_exch_mgr_add);
2222 * fc_exch_mgr_destroy() - Destroy an exchange manager
2223 * @kref: The reference to the EM to be destroyed
2225 static void fc_exch_mgr_destroy(struct kref *kref)
2227 struct fc_exch_mgr *mp = container_of(kref, struct fc_exch_mgr, kref);
2229 mempool_destroy(mp->ep_pool);
2230 free_percpu(mp->pool);
2235 * fc_exch_mgr_del() - Delete an EM from a local port's list
2236 * @ema: The exchange manager anchor identifying the EM to be deleted
2238 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema)
2240 /* remove EM anchor from EM anchors list */
2241 list_del(&ema->ema_list);
2242 kref_put(&ema->mp->kref, fc_exch_mgr_destroy);
2245 EXPORT_SYMBOL(fc_exch_mgr_del);
2248 * fc_exch_mgr_list_clone() - Share all exchange manager objects
2249 * @src: Source lport to clone exchange managers from
2250 * @dst: New lport that takes references to all the exchange managers
2252 int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst)
2254 struct fc_exch_mgr_anchor *ema, *tmp;
2256 list_for_each_entry(ema, &src->ema_list, ema_list) {
2257 if (!fc_exch_mgr_add(dst, ema->mp, ema->match))
2262 list_for_each_entry_safe(ema, tmp, &dst->ema_list, ema_list)
2263 fc_exch_mgr_del(ema);
2266 EXPORT_SYMBOL(fc_exch_mgr_list_clone);
2269 * fc_exch_mgr_alloc() - Allocate an exchange manager
2270 * @lport: The local port that the new EM will be associated with
2271 * @class: The default FC class for new exchanges
2272 * @min_xid: The minimum XID for exchanges from the new EM
2273 * @max_xid: The maximum XID for exchanges from the new EM
2274 * @match: The match routine for the new EM
2276 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lport,
2277 enum fc_class class,
2278 u16 min_xid, u16 max_xid,
2279 bool (*match)(struct fc_frame *))
2281 struct fc_exch_mgr *mp;
2282 u16 pool_exch_range;
2285 struct fc_exch_pool *pool;
2287 if (max_xid <= min_xid || max_xid == FC_XID_UNKNOWN ||
2288 (min_xid & fc_cpu_mask) != 0) {
2289 FC_LPORT_DBG(lport, "Invalid min_xid 0x:%x and max_xid 0x:%x\n",
2295 * allocate memory for EM
2297 mp = kzalloc(sizeof(struct fc_exch_mgr), GFP_ATOMIC);
2302 /* adjust em exch xid range for offload */
2303 mp->min_xid = min_xid;
2305 /* reduce range so per cpu pool fits into PCPU_MIN_UNIT_SIZE pool */
2306 pool_exch_range = (PCPU_MIN_UNIT_SIZE - sizeof(*pool)) /
2307 sizeof(struct fc_exch *);
2308 if ((max_xid - min_xid + 1) / (fc_cpu_mask + 1) > pool_exch_range) {
2309 mp->max_xid = pool_exch_range * (fc_cpu_mask + 1) +
2312 mp->max_xid = max_xid;
2313 pool_exch_range = (mp->max_xid - mp->min_xid + 1) /
2317 mp->ep_pool = mempool_create_slab_pool(2, fc_em_cachep);
2322 * Setup per cpu exch pool with entire exchange id range equally
2323 * divided across all cpus. The exch pointers array memory is
2324 * allocated for exch range per pool.
2326 mp->pool_max_index = pool_exch_range - 1;
2329 * Allocate and initialize per cpu exch pool
2331 pool_size = sizeof(*pool) + pool_exch_range * sizeof(struct fc_exch *);
2332 mp->pool = __alloc_percpu(pool_size, __alignof__(struct fc_exch_pool));
2335 for_each_possible_cpu(cpu) {
2336 pool = per_cpu_ptr(mp->pool, cpu);
2337 pool->next_index = 0;
2338 pool->left = FC_XID_UNKNOWN;
2339 pool->right = FC_XID_UNKNOWN;
2340 spin_lock_init(&pool->lock);
2341 INIT_LIST_HEAD(&pool->ex_list);
2344 kref_init(&mp->kref);
2345 if (!fc_exch_mgr_add(lport, mp, match)) {
2346 free_percpu(mp->pool);
2351 * Above kref_init() sets mp->kref to 1 and then
2352 * call to fc_exch_mgr_add incremented mp->kref again,
2353 * so adjust that extra increment.
2355 kref_put(&mp->kref, fc_exch_mgr_destroy);
2359 mempool_destroy(mp->ep_pool);
2364 EXPORT_SYMBOL(fc_exch_mgr_alloc);
2367 * fc_exch_mgr_free() - Free all exchange managers on a local port
2368 * @lport: The local port whose EMs are to be freed
2370 void fc_exch_mgr_free(struct fc_lport *lport)
2372 struct fc_exch_mgr_anchor *ema, *next;
2374 flush_workqueue(fc_exch_workqueue);
2375 list_for_each_entry_safe(ema, next, &lport->ema_list, ema_list)
2376 fc_exch_mgr_del(ema);
2378 EXPORT_SYMBOL(fc_exch_mgr_free);
2381 * fc_find_ema() - Lookup and return appropriate Exchange Manager Anchor depending
2384 * @lport: The local port the frame was received on
2385 * @fh: The received frame header
2387 static struct fc_exch_mgr_anchor *fc_find_ema(u32 f_ctl,
2388 struct fc_lport *lport,
2389 struct fc_frame_header *fh)
2391 struct fc_exch_mgr_anchor *ema;
2394 if (f_ctl & FC_FC_EX_CTX)
2395 xid = ntohs(fh->fh_ox_id);
2397 xid = ntohs(fh->fh_rx_id);
2398 if (xid == FC_XID_UNKNOWN)
2399 return list_entry(lport->ema_list.prev,
2400 typeof(*ema), ema_list);
2403 list_for_each_entry(ema, &lport->ema_list, ema_list) {
2404 if ((xid >= ema->mp->min_xid) &&
2405 (xid <= ema->mp->max_xid))
2411 * fc_exch_recv() - Handler for received frames
2412 * @lport: The local port the frame was received on
2413 * @fp: The received frame
2415 void fc_exch_recv(struct fc_lport *lport, struct fc_frame *fp)
2417 struct fc_frame_header *fh = fc_frame_header_get(fp);
2418 struct fc_exch_mgr_anchor *ema;
2422 if (!lport || lport->state == LPORT_ST_DISABLED) {
2423 FC_LPORT_DBG(lport, "Receiving frames for an lport that "
2424 "has not been initialized correctly\n");
2429 f_ctl = ntoh24(fh->fh_f_ctl);
2430 ema = fc_find_ema(f_ctl, lport, fh);
2432 FC_LPORT_DBG(lport, "Unable to find Exchange Manager Anchor,"
2433 "fc_ctl <0x%x>, xid <0x%x>\n",
2435 (f_ctl & FC_FC_EX_CTX) ?
2436 ntohs(fh->fh_ox_id) :
2437 ntohs(fh->fh_rx_id));
2443 * If frame is marked invalid, just drop it.
2445 switch (fr_eof(fp)) {
2447 if (f_ctl & FC_FC_END_SEQ)
2448 skb_trim(fp_skb(fp), fr_len(fp) - FC_FC_FILL(f_ctl));
2451 if (fh->fh_type == FC_TYPE_BLS)
2452 fc_exch_recv_bls(ema->mp, fp);
2453 else if ((f_ctl & (FC_FC_EX_CTX | FC_FC_SEQ_CTX)) ==
2455 fc_exch_recv_seq_resp(ema->mp, fp);
2456 else if (f_ctl & FC_FC_SEQ_CTX)
2457 fc_exch_recv_resp(ema->mp, fp);
2458 else /* no EX_CTX and no SEQ_CTX */
2459 fc_exch_recv_req(lport, ema->mp, fp);
2462 FC_LPORT_DBG(lport, "dropping invalid frame (eof %x)",
2467 EXPORT_SYMBOL(fc_exch_recv);
2470 * fc_exch_init() - Initialize the exchange layer for a local port
2471 * @lport: The local port to initialize the exchange layer for
2473 int fc_exch_init(struct fc_lport *lport)
2475 if (!lport->tt.seq_start_next)
2476 lport->tt.seq_start_next = fc_seq_start_next;
2478 if (!lport->tt.seq_set_resp)
2479 lport->tt.seq_set_resp = fc_seq_set_resp;
2481 if (!lport->tt.exch_seq_send)
2482 lport->tt.exch_seq_send = fc_exch_seq_send;
2484 if (!lport->tt.seq_send)
2485 lport->tt.seq_send = fc_seq_send;
2487 if (!lport->tt.seq_els_rsp_send)
2488 lport->tt.seq_els_rsp_send = fc_seq_els_rsp_send;
2490 if (!lport->tt.exch_done)
2491 lport->tt.exch_done = fc_exch_done;
2493 if (!lport->tt.exch_mgr_reset)
2494 lport->tt.exch_mgr_reset = fc_exch_mgr_reset;
2496 if (!lport->tt.seq_exch_abort)
2497 lport->tt.seq_exch_abort = fc_seq_exch_abort;
2499 if (!lport->tt.seq_assign)
2500 lport->tt.seq_assign = fc_seq_assign;
2502 if (!lport->tt.seq_release)
2503 lport->tt.seq_release = fc_seq_release;
2507 EXPORT_SYMBOL(fc_exch_init);
2510 * fc_setup_exch_mgr() - Setup an exchange manager
2512 int fc_setup_exch_mgr(void)
2514 fc_em_cachep = kmem_cache_create("libfc_em", sizeof(struct fc_exch),
2515 0, SLAB_HWCACHE_ALIGN, NULL);
2520 * Initialize fc_cpu_mask and fc_cpu_order. The
2521 * fc_cpu_mask is set for nr_cpu_ids rounded up
2522 * to order of 2's * power and order is stored
2523 * in fc_cpu_order as this is later required in
2524 * mapping between an exch id and exch array index
2525 * in per cpu exch pool.
2527 * This round up is required to align fc_cpu_mask
2528 * to exchange id's lower bits such that all incoming
2529 * frames of an exchange gets delivered to the same
2530 * cpu on which exchange originated by simple bitwise
2531 * AND operation between fc_cpu_mask and exchange id.
2535 while (fc_cpu_mask < nr_cpu_ids) {
2541 fc_exch_workqueue = create_singlethread_workqueue("fc_exch_workqueue");
2542 if (!fc_exch_workqueue)
2546 kmem_cache_destroy(fc_em_cachep);
2551 * fc_destroy_exch_mgr() - Destroy an exchange manager
2553 void fc_destroy_exch_mgr(void)
2555 destroy_workqueue(fc_exch_workqueue);
2556 kmem_cache_destroy(fc_em_cachep);