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;
307 * Initialize remainig fh fields
308 * from fc_fill_fc_hdr
310 fh->fh_ox_id = htons(ep->oxid);
311 fh->fh_rx_id = htons(ep->rxid);
312 fh->fh_seq_id = ep->seq.id;
313 fh->fh_seq_cnt = htons(ep->seq.cnt);
317 * fc_exch_release() - Decrement an exchange's reference count
318 * @ep: Exchange to be released
320 * If the reference count reaches zero and the exchange is complete,
323 static void fc_exch_release(struct fc_exch *ep)
325 struct fc_exch_mgr *mp;
327 if (atomic_dec_and_test(&ep->ex_refcnt)) {
330 ep->destructor(&ep->seq, ep->arg);
331 WARN_ON(!(ep->esb_stat & ESB_ST_COMPLETE));
332 mempool_free(ep, mp->ep_pool);
337 * fc_exch_done_locked() - Complete an exchange with the exchange lock held
338 * @ep: The exchange that is complete
340 static int fc_exch_done_locked(struct fc_exch *ep)
345 * We must check for completion in case there are two threads
346 * tyring to complete this. But the rrq code will reuse the
347 * ep, and in that case we only clear the resp and set it as
348 * complete, so it can be reused by the timer to send the rrq.
351 if (ep->state & FC_EX_DONE)
353 ep->esb_stat |= ESB_ST_COMPLETE;
355 if (!(ep->esb_stat & ESB_ST_REC_QUAL)) {
356 ep->state |= FC_EX_DONE;
357 if (cancel_delayed_work(&ep->timeout_work))
358 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */
365 * fc_exch_ptr_get() - Return an exchange from an exchange pool
366 * @pool: Exchange Pool to get an exchange from
367 * @index: Index of the exchange within the pool
369 * Use the index to get an exchange from within an exchange pool. exches
370 * will point to an array of exchange pointers. The index will select
371 * the exchange within the array.
373 static inline struct fc_exch *fc_exch_ptr_get(struct fc_exch_pool *pool,
376 struct fc_exch **exches = (struct fc_exch **)(pool + 1);
377 return exches[index];
381 * fc_exch_ptr_set() - Assign an exchange to a slot in an exchange pool
382 * @pool: The pool to assign the exchange to
383 * @index: The index in the pool where the exchange will be assigned
384 * @ep: The exchange to assign to the pool
386 static inline void fc_exch_ptr_set(struct fc_exch_pool *pool, u16 index,
389 ((struct fc_exch **)(pool + 1))[index] = ep;
393 * fc_exch_delete() - Delete an exchange
394 * @ep: The exchange to be deleted
396 static void fc_exch_delete(struct fc_exch *ep)
398 struct fc_exch_pool *pool;
402 spin_lock_bh(&pool->lock);
403 WARN_ON(pool->total_exches <= 0);
404 pool->total_exches--;
406 /* update cache of free slot */
407 index = (ep->xid - ep->em->min_xid) >> fc_cpu_order;
408 if (pool->left == FC_XID_UNKNOWN)
410 else if (pool->right == FC_XID_UNKNOWN)
413 pool->next_index = index;
415 fc_exch_ptr_set(pool, index, NULL);
416 list_del(&ep->ex_list);
417 spin_unlock_bh(&pool->lock);
418 fc_exch_release(ep); /* drop hold for exch in mp */
422 * fc_exch_timer_set_locked() - Start a timer for an exchange w/ the
423 * the exchange lock held
424 * @ep: The exchange whose timer will start
425 * @timer_msec: The timeout period
427 * Used for upper level protocols to time out the exchange.
428 * The timer is cancelled when it fires or when the exchange completes.
430 static inline void fc_exch_timer_set_locked(struct fc_exch *ep,
431 unsigned int timer_msec)
433 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
436 FC_EXCH_DBG(ep, "Exchange timer armed\n");
438 if (queue_delayed_work(fc_exch_workqueue, &ep->timeout_work,
439 msecs_to_jiffies(timer_msec)))
440 fc_exch_hold(ep); /* hold for timer */
444 * fc_exch_timer_set() - Lock the exchange and set the timer
445 * @ep: The exchange whose timer will start
446 * @timer_msec: The timeout period
448 static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec)
450 spin_lock_bh(&ep->ex_lock);
451 fc_exch_timer_set_locked(ep, timer_msec);
452 spin_unlock_bh(&ep->ex_lock);
456 * fc_seq_send() - Send a frame using existing sequence/exchange pair
457 * @lport: The local port that the exchange will be sent on
458 * @sp: The sequence to be sent
459 * @fp: The frame to be sent on the exchange
461 static int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp,
465 struct fc_frame_header *fh = fc_frame_header_get(fp);
468 u8 fh_type = fh->fh_type;
470 ep = fc_seq_exch(sp);
471 WARN_ON((ep->esb_stat & ESB_ST_SEQ_INIT) != ESB_ST_SEQ_INIT);
473 f_ctl = ntoh24(fh->fh_f_ctl);
474 fc_exch_setup_hdr(ep, fp, f_ctl);
475 fr_encaps(fp) = ep->encaps;
478 * update sequence count if this frame is carrying
479 * multiple FC frames when sequence offload is enabled
482 if (fr_max_payload(fp))
483 sp->cnt += DIV_ROUND_UP((fr_len(fp) - sizeof(*fh)),
491 error = lport->tt.frame_send(lport, fp);
493 if (fh_type == FC_TYPE_BLS)
497 * Update the exchange and sequence flags,
498 * assuming all frames for the sequence have been sent.
499 * We can only be called to send once for each sequence.
501 spin_lock_bh(&ep->ex_lock);
502 ep->f_ctl = f_ctl & ~FC_FC_FIRST_SEQ; /* not first seq */
503 if (f_ctl & FC_FC_SEQ_INIT)
504 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
505 spin_unlock_bh(&ep->ex_lock);
510 * fc_seq_alloc() - Allocate a sequence for a given exchange
511 * @ep: The exchange to allocate a new sequence for
512 * @seq_id: The sequence ID to be used
514 * We don't support multiple originated sequences on the same exchange.
515 * By implication, any previously originated sequence on this exchange
516 * is complete, and we reallocate the same sequence.
518 static struct fc_seq *fc_seq_alloc(struct fc_exch *ep, u8 seq_id)
530 * fc_seq_start_next_locked() - Allocate a new sequence on the same
531 * exchange as the supplied sequence
532 * @sp: The sequence/exchange to get a new sequence for
534 static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp)
536 struct fc_exch *ep = fc_seq_exch(sp);
538 sp = fc_seq_alloc(ep, ep->seq_id++);
539 FC_EXCH_DBG(ep, "f_ctl %6x seq %2x\n",
545 * fc_seq_start_next() - Lock the exchange and get a new sequence
546 * for a given sequence/exchange pair
547 * @sp: The sequence/exchange to get a new exchange for
549 static struct fc_seq *fc_seq_start_next(struct fc_seq *sp)
551 struct fc_exch *ep = fc_seq_exch(sp);
553 spin_lock_bh(&ep->ex_lock);
554 sp = fc_seq_start_next_locked(sp);
555 spin_unlock_bh(&ep->ex_lock);
561 * Set the response handler for the exchange associated with a sequence.
563 static void fc_seq_set_resp(struct fc_seq *sp,
564 void (*resp)(struct fc_seq *, struct fc_frame *,
568 struct fc_exch *ep = fc_seq_exch(sp);
570 spin_lock_bh(&ep->ex_lock);
573 spin_unlock_bh(&ep->ex_lock);
577 * fc_exch_abort_locked() - Abort an exchange
578 * @ep: The exchange to be aborted
579 * @timer_msec: The period of time to wait before aborting
581 * Locking notes: Called with exch lock held
583 * Return value: 0 on success else error code
585 static int fc_exch_abort_locked(struct fc_exch *ep,
586 unsigned int timer_msec)
592 if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL) ||
593 ep->state & (FC_EX_DONE | FC_EX_RST_CLEANUP))
597 * Send the abort on a new sequence if possible.
599 sp = fc_seq_start_next_locked(&ep->seq);
603 ep->esb_stat |= ESB_ST_SEQ_INIT | ESB_ST_ABNORMAL;
605 fc_exch_timer_set_locked(ep, timer_msec);
608 * If not logged into the fabric, don't send ABTS but leave
609 * sequence active until next timeout.
615 * Send an abort for the sequence that timed out.
617 fp = fc_frame_alloc(ep->lp, 0);
619 fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid,
620 FC_TYPE_BLS, FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
621 error = fc_seq_send(ep->lp, sp, fp);
628 * fc_seq_exch_abort() - Abort an exchange and sequence
629 * @req_sp: The sequence to be aborted
630 * @timer_msec: The period of time to wait before aborting
632 * Generally called because of a timeout or an abort from the upper layer.
634 * Return value: 0 on success else error code
636 static int fc_seq_exch_abort(const struct fc_seq *req_sp,
637 unsigned int timer_msec)
642 ep = fc_seq_exch(req_sp);
643 spin_lock_bh(&ep->ex_lock);
644 error = fc_exch_abort_locked(ep, timer_msec);
645 spin_unlock_bh(&ep->ex_lock);
650 * fc_exch_timeout() - Handle exchange timer expiration
651 * @work: The work_struct identifying the exchange that timed out
653 static void fc_exch_timeout(struct work_struct *work)
655 struct fc_exch *ep = container_of(work, struct fc_exch,
657 struct fc_seq *sp = &ep->seq;
658 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
663 FC_EXCH_DBG(ep, "Exchange timed out\n");
665 spin_lock_bh(&ep->ex_lock);
666 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
669 e_stat = ep->esb_stat;
670 if (e_stat & ESB_ST_COMPLETE) {
671 ep->esb_stat = e_stat & ~ESB_ST_REC_QUAL;
672 spin_unlock_bh(&ep->ex_lock);
673 if (e_stat & ESB_ST_REC_QUAL)
680 if (e_stat & ESB_ST_ABNORMAL)
681 rc = fc_exch_done_locked(ep);
682 spin_unlock_bh(&ep->ex_lock);
686 resp(sp, ERR_PTR(-FC_EX_TIMEOUT), arg);
687 fc_seq_exch_abort(sp, 2 * ep->r_a_tov);
691 spin_unlock_bh(&ep->ex_lock);
694 * This release matches the hold taken when the timer was set.
700 * fc_exch_em_alloc() - Allocate an exchange from a specified EM.
701 * @lport: The local port that the exchange is for
702 * @mp: The exchange manager that will allocate the exchange
704 * Returns pointer to allocated fc_exch with exch lock held.
706 static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport,
707 struct fc_exch_mgr *mp)
712 struct fc_exch_pool *pool;
714 /* allocate memory for exchange */
715 ep = mempool_alloc(mp->ep_pool, GFP_ATOMIC);
717 atomic_inc(&mp->stats.no_free_exch);
720 memset(ep, 0, sizeof(*ep));
723 pool = per_cpu_ptr(mp->pool, cpu);
724 spin_lock_bh(&pool->lock);
727 /* peek cache of free slot */
728 if (pool->left != FC_XID_UNKNOWN) {
730 pool->left = FC_XID_UNKNOWN;
733 if (pool->right != FC_XID_UNKNOWN) {
735 pool->right = FC_XID_UNKNOWN;
739 index = pool->next_index;
740 /* allocate new exch from pool */
741 while (fc_exch_ptr_get(pool, index)) {
742 index = index == mp->pool_max_index ? 0 : index + 1;
743 if (index == pool->next_index)
746 pool->next_index = index == mp->pool_max_index ? 0 : index + 1;
748 fc_exch_hold(ep); /* hold for exch in mp */
749 spin_lock_init(&ep->ex_lock);
751 * Hold exch lock for caller to prevent fc_exch_reset()
752 * from releasing exch while fc_exch_alloc() caller is
753 * still working on exch.
755 spin_lock_bh(&ep->ex_lock);
757 fc_exch_ptr_set(pool, index, ep);
758 list_add_tail(&ep->ex_list, &pool->ex_list);
759 fc_seq_alloc(ep, ep->seq_id++);
760 pool->total_exches++;
761 spin_unlock_bh(&pool->lock);
766 ep->oxid = ep->xid = (index << fc_cpu_order | cpu) + mp->min_xid;
770 ep->f_ctl = FC_FC_FIRST_SEQ; /* next seq is first seq */
771 ep->rxid = FC_XID_UNKNOWN;
772 ep->class = mp->class;
773 INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout);
777 spin_unlock_bh(&pool->lock);
778 atomic_inc(&mp->stats.no_free_exch_xid);
779 mempool_free(ep, mp->ep_pool);
784 * fc_exch_alloc() - Allocate an exchange from an EM on a
785 * local port's list of EMs.
786 * @lport: The local port that will own the exchange
787 * @fp: The FC frame that the exchange will be for
789 * This function walks the list of exchange manager(EM)
790 * anchors to select an EM for a new exchange allocation. The
791 * EM is selected when a NULL match function pointer is encountered
792 * or when a call to a match function returns true.
794 static inline struct fc_exch *fc_exch_alloc(struct fc_lport *lport,
797 struct fc_exch_mgr_anchor *ema;
799 list_for_each_entry(ema, &lport->ema_list, ema_list)
800 if (!ema->match || ema->match(fp))
801 return fc_exch_em_alloc(lport, ema->mp);
806 * fc_exch_find() - Lookup and hold an exchange
807 * @mp: The exchange manager to lookup the exchange from
808 * @xid: The XID of the exchange to look up
810 static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid)
812 struct fc_exch_pool *pool;
813 struct fc_exch *ep = NULL;
815 if ((xid >= mp->min_xid) && (xid <= mp->max_xid)) {
816 pool = per_cpu_ptr(mp->pool, xid & fc_cpu_mask);
817 spin_lock_bh(&pool->lock);
818 ep = fc_exch_ptr_get(pool, (xid - mp->min_xid) >> fc_cpu_order);
819 if (ep && ep->xid == xid)
821 spin_unlock_bh(&pool->lock);
828 * fc_exch_done() - Indicate that an exchange/sequence tuple is complete and
829 * the memory allocated for the related objects may be freed.
830 * @sp: The sequence that has completed
832 static void fc_exch_done(struct fc_seq *sp)
834 struct fc_exch *ep = fc_seq_exch(sp);
837 spin_lock_bh(&ep->ex_lock);
838 rc = fc_exch_done_locked(ep);
839 spin_unlock_bh(&ep->ex_lock);
845 * fc_exch_resp() - Allocate a new exchange for a response frame
846 * @lport: The local port that the exchange was for
847 * @mp: The exchange manager to allocate the exchange from
848 * @fp: The response frame
850 * Sets the responder ID in the frame header.
852 static struct fc_exch *fc_exch_resp(struct fc_lport *lport,
853 struct fc_exch_mgr *mp,
857 struct fc_frame_header *fh;
859 ep = fc_exch_alloc(lport, fp);
861 ep->class = fc_frame_class(fp);
864 * Set EX_CTX indicating we're responding on this exchange.
866 ep->f_ctl |= FC_FC_EX_CTX; /* we're responding */
867 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not new */
868 fh = fc_frame_header_get(fp);
869 ep->sid = ntoh24(fh->fh_d_id);
870 ep->did = ntoh24(fh->fh_s_id);
874 * Allocated exchange has placed the XID in the
875 * originator field. Move it to the responder field,
876 * and set the originator XID from the frame.
879 ep->oxid = ntohs(fh->fh_ox_id);
880 ep->esb_stat |= ESB_ST_RESP | ESB_ST_SEQ_INIT;
881 if ((ntoh24(fh->fh_f_ctl) & FC_FC_SEQ_INIT) == 0)
882 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
884 fc_exch_hold(ep); /* hold for caller */
885 spin_unlock_bh(&ep->ex_lock); /* lock from fc_exch_alloc */
891 * fc_seq_lookup_recip() - Find a sequence where the other end
892 * originated the sequence
893 * @lport: The local port that the frame was sent to
894 * @mp: The Exchange Manager to lookup the exchange from
895 * @fp: The frame associated with the sequence we're looking for
897 * If fc_pf_rjt_reason is FC_RJT_NONE then this function will have a hold
898 * on the ep that should be released by the caller.
900 static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport,
901 struct fc_exch_mgr *mp,
904 struct fc_frame_header *fh = fc_frame_header_get(fp);
905 struct fc_exch *ep = NULL;
906 struct fc_seq *sp = NULL;
907 enum fc_pf_rjt_reason reject = FC_RJT_NONE;
911 f_ctl = ntoh24(fh->fh_f_ctl);
912 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != 0);
915 * Lookup or create the exchange if we will be creating the sequence.
917 if (f_ctl & FC_FC_EX_CTX) {
918 xid = ntohs(fh->fh_ox_id); /* we originated exch */
919 ep = fc_exch_find(mp, xid);
921 atomic_inc(&mp->stats.xid_not_found);
922 reject = FC_RJT_OX_ID;
925 if (ep->rxid == FC_XID_UNKNOWN)
926 ep->rxid = ntohs(fh->fh_rx_id);
927 else if (ep->rxid != ntohs(fh->fh_rx_id)) {
928 reject = FC_RJT_OX_ID;
932 xid = ntohs(fh->fh_rx_id); /* we are the responder */
935 * Special case for MDS issuing an ELS TEST with a
937 * XXX take this out once we do the proper reject.
939 if (xid == 0 && fh->fh_r_ctl == FC_RCTL_ELS_REQ &&
940 fc_frame_payload_op(fp) == ELS_TEST) {
941 fh->fh_rx_id = htons(FC_XID_UNKNOWN);
942 xid = FC_XID_UNKNOWN;
946 * new sequence - find the exchange
948 ep = fc_exch_find(mp, xid);
949 if ((f_ctl & FC_FC_FIRST_SEQ) && fc_sof_is_init(fr_sof(fp))) {
951 atomic_inc(&mp->stats.xid_busy);
952 reject = FC_RJT_RX_ID;
955 ep = fc_exch_resp(lport, mp, fp);
957 reject = FC_RJT_EXCH_EST; /* XXX */
960 xid = ep->xid; /* get our XID */
962 atomic_inc(&mp->stats.xid_not_found);
963 reject = FC_RJT_RX_ID; /* XID not found */
969 * At this point, we have the exchange held.
970 * Find or create the sequence.
972 if (fc_sof_is_init(fr_sof(fp))) {
974 sp->ssb_stat |= SSB_ST_RESP;
975 sp->id = fh->fh_seq_id;
978 if (sp->id != fh->fh_seq_id) {
979 atomic_inc(&mp->stats.seq_not_found);
980 if (f_ctl & FC_FC_END_SEQ) {
982 * Update sequence_id based on incoming last
983 * frame of sequence exchange. This is needed
984 * for FC target where DDP has been used
985 * on target where, stack is indicated only
986 * about last frame's (payload _header) header.
987 * Whereas "seq_id" which is part of
988 * frame_header is allocated by initiator
989 * which is totally different from "seq_id"
990 * allocated when XFER_RDY was sent by target.
991 * To avoid false -ve which results into not
992 * sending RSP, hence write request on other
993 * end never finishes.
995 spin_lock_bh(&ep->ex_lock);
996 sp->ssb_stat |= SSB_ST_RESP;
997 sp->id = fh->fh_seq_id;
998 spin_unlock_bh(&ep->ex_lock);
1000 /* sequence/exch should exist */
1001 reject = FC_RJT_SEQ_ID;
1006 WARN_ON(ep != fc_seq_exch(sp));
1008 if (f_ctl & FC_FC_SEQ_INIT)
1009 ep->esb_stat |= ESB_ST_SEQ_INIT;
1015 fc_exch_done(&ep->seq);
1016 fc_exch_release(ep); /* hold from fc_exch_find/fc_exch_resp */
1021 * fc_seq_lookup_orig() - Find a sequence where this end
1022 * originated the sequence
1023 * @mp: The Exchange Manager to lookup the exchange from
1024 * @fp: The frame associated with the sequence we're looking for
1026 * Does not hold the sequence for the caller.
1028 static struct fc_seq *fc_seq_lookup_orig(struct fc_exch_mgr *mp,
1029 struct fc_frame *fp)
1031 struct fc_frame_header *fh = fc_frame_header_get(fp);
1033 struct fc_seq *sp = NULL;
1037 f_ctl = ntoh24(fh->fh_f_ctl);
1038 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != FC_FC_SEQ_CTX);
1039 xid = ntohs((f_ctl & FC_FC_EX_CTX) ? fh->fh_ox_id : fh->fh_rx_id);
1040 ep = fc_exch_find(mp, xid);
1043 if (ep->seq.id == fh->fh_seq_id) {
1045 * Save the RX_ID if we didn't previously know it.
1048 if ((f_ctl & FC_FC_EX_CTX) != 0 &&
1049 ep->rxid == FC_XID_UNKNOWN) {
1050 ep->rxid = ntohs(fh->fh_rx_id);
1053 fc_exch_release(ep);
1058 * fc_exch_set_addr() - Set the source and destination IDs for an exchange
1059 * @ep: The exchange to set the addresses for
1060 * @orig_id: The originator's ID
1061 * @resp_id: The responder's ID
1063 * Note this must be done before the first sequence of the exchange is sent.
1065 static void fc_exch_set_addr(struct fc_exch *ep,
1066 u32 orig_id, u32 resp_id)
1069 if (ep->esb_stat & ESB_ST_RESP) {
1079 * fc_seq_els_rsp_send() - Send an ELS response using information from
1080 * the existing sequence/exchange.
1081 * @fp: The received frame
1082 * @els_cmd: The ELS command to be sent
1083 * @els_data: The ELS data to be sent
1085 * The received frame is not freed.
1087 static void fc_seq_els_rsp_send(struct fc_frame *fp, enum fc_els_cmd els_cmd,
1088 struct fc_seq_els_data *els_data)
1092 fc_seq_ls_rjt(fp, els_data->reason, els_data->explan);
1098 fc_exch_els_rrq(fp);
1101 fc_exch_els_rec(fp);
1104 FC_LPORT_DBG(fr_dev(fp), "Invalid ELS CMD:%x\n", els_cmd);
1109 * fc_seq_send_last() - Send a sequence that is the last in the exchange
1110 * @sp: The sequence that is to be sent
1111 * @fp: The frame that will be sent on the sequence
1112 * @rctl: The R_CTL information to be sent
1113 * @fh_type: The frame header type
1115 static void fc_seq_send_last(struct fc_seq *sp, struct fc_frame *fp,
1116 enum fc_rctl rctl, enum fc_fh_type fh_type)
1119 struct fc_exch *ep = fc_seq_exch(sp);
1121 f_ctl = FC_FC_LAST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT;
1123 fc_fill_fc_hdr(fp, rctl, ep->did, ep->sid, fh_type, f_ctl, 0);
1124 fc_seq_send(ep->lp, sp, fp);
1128 * fc_seq_send_ack() - Send an acknowledgement that we've received a frame
1129 * @sp: The sequence to send the ACK on
1130 * @rx_fp: The received frame that is being acknoledged
1132 * Send ACK_1 (or equiv.) indicating we received something.
1134 static void fc_seq_send_ack(struct fc_seq *sp, const struct fc_frame *rx_fp)
1136 struct fc_frame *fp;
1137 struct fc_frame_header *rx_fh;
1138 struct fc_frame_header *fh;
1139 struct fc_exch *ep = fc_seq_exch(sp);
1140 struct fc_lport *lport = ep->lp;
1144 * Don't send ACKs for class 3.
1146 if (fc_sof_needs_ack(fr_sof(rx_fp))) {
1147 fp = fc_frame_alloc(lport, 0);
1151 fh = fc_frame_header_get(fp);
1152 fh->fh_r_ctl = FC_RCTL_ACK_1;
1153 fh->fh_type = FC_TYPE_BLS;
1156 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
1157 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
1158 * Bits 9-8 are meaningful (retransmitted or unidirectional).
1159 * Last ACK uses bits 7-6 (continue sequence),
1160 * bits 5-4 are meaningful (what kind of ACK to use).
1162 rx_fh = fc_frame_header_get(rx_fp);
1163 f_ctl = ntoh24(rx_fh->fh_f_ctl);
1164 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
1165 FC_FC_FIRST_SEQ | FC_FC_LAST_SEQ |
1166 FC_FC_END_SEQ | FC_FC_END_CONN | FC_FC_SEQ_INIT |
1167 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
1168 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
1169 hton24(fh->fh_f_ctl, f_ctl);
1171 fc_exch_setup_hdr(ep, fp, f_ctl);
1172 fh->fh_seq_id = rx_fh->fh_seq_id;
1173 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
1174 fh->fh_parm_offset = htonl(1); /* ack single frame */
1176 fr_sof(fp) = fr_sof(rx_fp);
1177 if (f_ctl & FC_FC_END_SEQ)
1178 fr_eof(fp) = FC_EOF_T;
1180 fr_eof(fp) = FC_EOF_N;
1182 lport->tt.frame_send(lport, fp);
1187 * fc_exch_send_ba_rjt() - Send BLS Reject
1188 * @rx_fp: The frame being rejected
1189 * @reason: The reason the frame is being rejected
1190 * @explan: The explanation for the rejection
1192 * This is for rejecting BA_ABTS only.
1194 static void fc_exch_send_ba_rjt(struct fc_frame *rx_fp,
1195 enum fc_ba_rjt_reason reason,
1196 enum fc_ba_rjt_explan explan)
1198 struct fc_frame *fp;
1199 struct fc_frame_header *rx_fh;
1200 struct fc_frame_header *fh;
1201 struct fc_ba_rjt *rp;
1202 struct fc_lport *lport;
1205 lport = fr_dev(rx_fp);
1206 fp = fc_frame_alloc(lport, sizeof(*rp));
1209 fh = fc_frame_header_get(fp);
1210 rx_fh = fc_frame_header_get(rx_fp);
1212 memset(fh, 0, sizeof(*fh) + sizeof(*rp));
1214 rp = fc_frame_payload_get(fp, sizeof(*rp));
1215 rp->br_reason = reason;
1216 rp->br_explan = explan;
1219 * seq_id, cs_ctl, df_ctl and param/offset are zero.
1221 memcpy(fh->fh_s_id, rx_fh->fh_d_id, 3);
1222 memcpy(fh->fh_d_id, rx_fh->fh_s_id, 3);
1223 fh->fh_ox_id = rx_fh->fh_ox_id;
1224 fh->fh_rx_id = rx_fh->fh_rx_id;
1225 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
1226 fh->fh_r_ctl = FC_RCTL_BA_RJT;
1227 fh->fh_type = FC_TYPE_BLS;
1230 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
1231 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
1232 * Bits 9-8 are meaningful (retransmitted or unidirectional).
1233 * Last ACK uses bits 7-6 (continue sequence),
1234 * bits 5-4 are meaningful (what kind of ACK to use).
1235 * Always set LAST_SEQ, END_SEQ.
1237 f_ctl = ntoh24(rx_fh->fh_f_ctl);
1238 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
1239 FC_FC_END_CONN | FC_FC_SEQ_INIT |
1240 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
1241 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
1242 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
1243 f_ctl &= ~FC_FC_FIRST_SEQ;
1244 hton24(fh->fh_f_ctl, f_ctl);
1246 fr_sof(fp) = fc_sof_class(fr_sof(rx_fp));
1247 fr_eof(fp) = FC_EOF_T;
1248 if (fc_sof_needs_ack(fr_sof(fp)))
1249 fr_eof(fp) = FC_EOF_N;
1251 lport->tt.frame_send(lport, fp);
1255 * fc_exch_recv_abts() - Handle an incoming ABTS
1256 * @ep: The exchange the abort was on
1257 * @rx_fp: The ABTS frame
1259 * This would be for target mode usually, but could be due to lost
1260 * FCP transfer ready, confirm or RRQ. We always handle this as an
1261 * exchange abort, ignoring the parameter.
1263 static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp)
1265 struct fc_frame *fp;
1266 struct fc_ba_acc *ap;
1267 struct fc_frame_header *fh;
1272 spin_lock_bh(&ep->ex_lock);
1273 if (ep->esb_stat & ESB_ST_COMPLETE) {
1274 spin_unlock_bh(&ep->ex_lock);
1277 if (!(ep->esb_stat & ESB_ST_REC_QUAL))
1278 fc_exch_hold(ep); /* hold for REC_QUAL */
1279 ep->esb_stat |= ESB_ST_ABNORMAL | ESB_ST_REC_QUAL;
1280 fc_exch_timer_set_locked(ep, ep->r_a_tov);
1282 fp = fc_frame_alloc(ep->lp, sizeof(*ap));
1284 spin_unlock_bh(&ep->ex_lock);
1287 fh = fc_frame_header_get(fp);
1288 ap = fc_frame_payload_get(fp, sizeof(*ap));
1289 memset(ap, 0, sizeof(*ap));
1291 ap->ba_high_seq_cnt = htons(0xffff);
1292 if (sp->ssb_stat & SSB_ST_RESP) {
1293 ap->ba_seq_id = sp->id;
1294 ap->ba_seq_id_val = FC_BA_SEQ_ID_VAL;
1295 ap->ba_high_seq_cnt = fh->fh_seq_cnt;
1296 ap->ba_low_seq_cnt = htons(sp->cnt);
1298 sp = fc_seq_start_next_locked(sp);
1299 spin_unlock_bh(&ep->ex_lock);
1300 fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS);
1301 fc_frame_free(rx_fp);
1305 fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID);
1307 fc_frame_free(rx_fp);
1311 * fc_seq_assign() - Assign exchange and sequence for incoming request
1312 * @lport: The local port that received the request
1313 * @fp: The request frame
1315 * On success, the sequence pointer will be returned and also in fr_seq(@fp).
1316 * A reference will be held on the exchange/sequence for the caller, which
1317 * must call fc_seq_release().
1319 static struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp)
1321 struct fc_exch_mgr_anchor *ema;
1323 WARN_ON(lport != fr_dev(fp));
1324 WARN_ON(fr_seq(fp));
1327 list_for_each_entry(ema, &lport->ema_list, ema_list)
1328 if ((!ema->match || ema->match(fp)) &&
1329 fc_seq_lookup_recip(lport, ema->mp, fp) == FC_RJT_NONE)
1335 * fc_seq_release() - Release the hold
1336 * @sp: The sequence.
1338 static void fc_seq_release(struct fc_seq *sp)
1340 fc_exch_release(fc_seq_exch(sp));
1344 * fc_exch_recv_req() - Handler for an incoming request
1345 * @lport: The local port that received the request
1346 * @mp: The EM that the exchange is on
1347 * @fp: The request frame
1349 * This is used when the other end is originating the exchange
1352 static void fc_exch_recv_req(struct fc_lport *lport, struct fc_exch_mgr *mp,
1353 struct fc_frame *fp)
1355 struct fc_frame_header *fh = fc_frame_header_get(fp);
1356 struct fc_seq *sp = NULL;
1357 struct fc_exch *ep = NULL;
1358 enum fc_pf_rjt_reason reject;
1360 /* We can have the wrong fc_lport at this point with NPIV, which is a
1361 * problem now that we know a new exchange needs to be allocated
1363 lport = fc_vport_id_lookup(lport, ntoh24(fh->fh_d_id));
1370 BUG_ON(fr_seq(fp)); /* XXX remove later */
1373 * If the RX_ID is 0xffff, don't allocate an exchange.
1374 * The upper-level protocol may request one later, if needed.
1376 if (fh->fh_rx_id == htons(FC_XID_UNKNOWN))
1377 return lport->tt.lport_recv(lport, fp);
1379 reject = fc_seq_lookup_recip(lport, mp, fp);
1380 if (reject == FC_RJT_NONE) {
1381 sp = fr_seq(fp); /* sequence will be held */
1382 ep = fc_seq_exch(sp);
1383 fc_seq_send_ack(sp, fp);
1384 ep->encaps = fr_encaps(fp);
1387 * Call the receive function.
1389 * The receive function may allocate a new sequence
1390 * over the old one, so we shouldn't change the
1391 * sequence after this.
1393 * The frame will be freed by the receive function.
1394 * If new exch resp handler is valid then call that
1398 ep->resp(sp, fp, ep->arg);
1400 lport->tt.lport_recv(lport, fp);
1401 fc_exch_release(ep); /* release from lookup */
1403 FC_LPORT_DBG(lport, "exch/seq lookup failed: reject %x\n",
1410 * fc_exch_recv_seq_resp() - Handler for an incoming response where the other
1411 * end is the originator of the sequence that is a
1412 * response to our initial exchange
1413 * @mp: The EM that the exchange is on
1414 * @fp: The response frame
1416 static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1418 struct fc_frame_header *fh = fc_frame_header_get(fp);
1423 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1427 ep = fc_exch_find(mp, ntohs(fh->fh_ox_id));
1429 atomic_inc(&mp->stats.xid_not_found);
1432 if (ep->esb_stat & ESB_ST_COMPLETE) {
1433 atomic_inc(&mp->stats.xid_not_found);
1436 if (ep->rxid == FC_XID_UNKNOWN)
1437 ep->rxid = ntohs(fh->fh_rx_id);
1438 if (ep->sid != 0 && ep->sid != ntoh24(fh->fh_d_id)) {
1439 atomic_inc(&mp->stats.xid_not_found);
1442 if (ep->did != ntoh24(fh->fh_s_id) &&
1443 ep->did != FC_FID_FLOGI) {
1444 atomic_inc(&mp->stats.xid_not_found);
1449 if (fc_sof_is_init(sof)) {
1450 sp->ssb_stat |= SSB_ST_RESP;
1451 sp->id = fh->fh_seq_id;
1452 } else if (sp->id != fh->fh_seq_id) {
1453 atomic_inc(&mp->stats.seq_not_found);
1457 f_ctl = ntoh24(fh->fh_f_ctl);
1459 if (f_ctl & FC_FC_SEQ_INIT)
1460 ep->esb_stat |= ESB_ST_SEQ_INIT;
1462 if (fc_sof_needs_ack(sof))
1463 fc_seq_send_ack(sp, fp);
1465 ex_resp_arg = ep->arg;
1467 if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T &&
1468 (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) ==
1469 (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) {
1470 spin_lock_bh(&ep->ex_lock);
1472 rc = fc_exch_done_locked(ep);
1473 WARN_ON(fc_seq_exch(sp) != ep);
1474 spin_unlock_bh(&ep->ex_lock);
1480 * Call the receive function.
1481 * The sequence is held (has a refcnt) for us,
1482 * but not for the receive function.
1484 * The receive function may allocate a new sequence
1485 * over the old one, so we shouldn't change the
1486 * sequence after this.
1488 * The frame will be freed by the receive function.
1489 * If new exch resp handler is valid then call that
1493 resp(sp, fp, ex_resp_arg);
1496 fc_exch_release(ep);
1499 fc_exch_release(ep);
1505 * fc_exch_recv_resp() - Handler for a sequence where other end is
1506 * responding to our sequence
1507 * @mp: The EM that the exchange is on
1508 * @fp: The response frame
1510 static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1514 sp = fc_seq_lookup_orig(mp, fp); /* doesn't hold sequence */
1517 atomic_inc(&mp->stats.xid_not_found);
1519 atomic_inc(&mp->stats.non_bls_resp);
1525 * fc_exch_abts_resp() - Handler for a response to an ABT
1526 * @ep: The exchange that the frame is on
1527 * @fp: The response frame
1529 * This response would be to an ABTS cancelling an exchange or sequence.
1530 * The response can be either BA_ACC or BA_RJT
1532 static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp)
1534 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1536 struct fc_frame_header *fh;
1537 struct fc_ba_acc *ap;
1541 int rc = 1, has_rec = 0;
1543 fh = fc_frame_header_get(fp);
1544 FC_EXCH_DBG(ep, "exch: BLS rctl %x - %s\n", fh->fh_r_ctl,
1545 fc_exch_rctl_name(fh->fh_r_ctl));
1547 if (cancel_delayed_work_sync(&ep->timeout_work))
1548 fc_exch_release(ep); /* release from pending timer hold */
1550 spin_lock_bh(&ep->ex_lock);
1551 switch (fh->fh_r_ctl) {
1552 case FC_RCTL_BA_ACC:
1553 ap = fc_frame_payload_get(fp, sizeof(*ap));
1558 * Decide whether to establish a Recovery Qualifier.
1559 * We do this if there is a non-empty SEQ_CNT range and
1560 * SEQ_ID is the same as the one we aborted.
1562 low = ntohs(ap->ba_low_seq_cnt);
1563 high = ntohs(ap->ba_high_seq_cnt);
1564 if ((ep->esb_stat & ESB_ST_REC_QUAL) == 0 &&
1565 (ap->ba_seq_id_val != FC_BA_SEQ_ID_VAL ||
1566 ap->ba_seq_id == ep->seq_id) && low != high) {
1567 ep->esb_stat |= ESB_ST_REC_QUAL;
1568 fc_exch_hold(ep); /* hold for recovery qualifier */
1572 case FC_RCTL_BA_RJT:
1579 ex_resp_arg = ep->arg;
1581 /* do we need to do some other checks here. Can we reuse more of
1582 * fc_exch_recv_seq_resp
1586 * do we want to check END_SEQ as well as LAST_SEQ here?
1588 if (ep->fh_type != FC_TYPE_FCP &&
1589 ntoh24(fh->fh_f_ctl) & FC_FC_LAST_SEQ)
1590 rc = fc_exch_done_locked(ep);
1591 spin_unlock_bh(&ep->ex_lock);
1596 resp(sp, fp, ex_resp_arg);
1601 fc_exch_timer_set(ep, ep->r_a_tov);
1606 * fc_exch_recv_bls() - Handler for a BLS sequence
1607 * @mp: The EM that the exchange is on
1608 * @fp: The request frame
1610 * The BLS frame is always a sequence initiated by the remote side.
1611 * We may be either the originator or recipient of the exchange.
1613 static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp)
1615 struct fc_frame_header *fh;
1619 fh = fc_frame_header_get(fp);
1620 f_ctl = ntoh24(fh->fh_f_ctl);
1623 ep = fc_exch_find(mp, (f_ctl & FC_FC_EX_CTX) ?
1624 ntohs(fh->fh_ox_id) : ntohs(fh->fh_rx_id));
1625 if (ep && (f_ctl & FC_FC_SEQ_INIT)) {
1626 spin_lock_bh(&ep->ex_lock);
1627 ep->esb_stat |= ESB_ST_SEQ_INIT;
1628 spin_unlock_bh(&ep->ex_lock);
1630 if (f_ctl & FC_FC_SEQ_CTX) {
1632 * A response to a sequence we initiated.
1633 * This should only be ACKs for class 2 or F.
1635 switch (fh->fh_r_ctl) {
1641 FC_EXCH_DBG(ep, "BLS rctl %x - %s received",
1643 fc_exch_rctl_name(fh->fh_r_ctl));
1648 switch (fh->fh_r_ctl) {
1649 case FC_RCTL_BA_RJT:
1650 case FC_RCTL_BA_ACC:
1652 fc_exch_abts_resp(ep, fp);
1656 case FC_RCTL_BA_ABTS:
1657 fc_exch_recv_abts(ep, fp);
1659 default: /* ignore junk */
1665 fc_exch_release(ep); /* release hold taken by fc_exch_find */
1669 * fc_seq_ls_acc() - Accept sequence with LS_ACC
1670 * @rx_fp: The received frame, not freed here.
1672 * If this fails due to allocation or transmit congestion, assume the
1673 * originator will repeat the sequence.
1675 static void fc_seq_ls_acc(struct fc_frame *rx_fp)
1677 struct fc_lport *lport;
1678 struct fc_els_ls_acc *acc;
1679 struct fc_frame *fp;
1681 lport = fr_dev(rx_fp);
1682 fp = fc_frame_alloc(lport, sizeof(*acc));
1685 acc = fc_frame_payload_get(fp, sizeof(*acc));
1686 memset(acc, 0, sizeof(*acc));
1687 acc->la_cmd = ELS_LS_ACC;
1688 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
1689 lport->tt.frame_send(lport, fp);
1693 * fc_seq_ls_rjt() - Reject a sequence with ELS LS_RJT
1694 * @rx_fp: The received frame, not freed here.
1695 * @reason: The reason the sequence is being rejected
1696 * @explan: The explanation for the rejection
1698 * If this fails due to allocation or transmit congestion, assume the
1699 * originator will repeat the sequence.
1701 static void fc_seq_ls_rjt(struct fc_frame *rx_fp, enum fc_els_rjt_reason reason,
1702 enum fc_els_rjt_explan explan)
1704 struct fc_lport *lport;
1705 struct fc_els_ls_rjt *rjt;
1706 struct fc_frame *fp;
1708 lport = fr_dev(rx_fp);
1709 fp = fc_frame_alloc(lport, sizeof(*rjt));
1712 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1713 memset(rjt, 0, sizeof(*rjt));
1714 rjt->er_cmd = ELS_LS_RJT;
1715 rjt->er_reason = reason;
1716 rjt->er_explan = explan;
1717 fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, 0);
1718 lport->tt.frame_send(lport, fp);
1722 * fc_exch_reset() - Reset an exchange
1723 * @ep: The exchange to be reset
1725 static void fc_exch_reset(struct fc_exch *ep)
1728 void (*resp)(struct fc_seq *, struct fc_frame *, void *);
1732 spin_lock_bh(&ep->ex_lock);
1733 fc_exch_abort_locked(ep, 0);
1734 ep->state |= FC_EX_RST_CLEANUP;
1735 if (cancel_delayed_work(&ep->timeout_work))
1736 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */
1739 if (ep->esb_stat & ESB_ST_REC_QUAL)
1740 atomic_dec(&ep->ex_refcnt); /* drop hold for rec_qual */
1741 ep->esb_stat &= ~ESB_ST_REC_QUAL;
1744 rc = fc_exch_done_locked(ep);
1745 spin_unlock_bh(&ep->ex_lock);
1750 resp(sp, ERR_PTR(-FC_EX_CLOSED), arg);
1754 * fc_exch_pool_reset() - Reset a per cpu exchange pool
1755 * @lport: The local port that the exchange pool is on
1756 * @pool: The exchange pool to be reset
1757 * @sid: The source ID
1758 * @did: The destination ID
1760 * Resets a per cpu exches pool, releasing all of its sequences
1761 * and exchanges. If sid is non-zero then reset only exchanges
1762 * we sourced from the local port's FID. If did is non-zero then
1763 * only reset exchanges destined for the local port's FID.
1765 static void fc_exch_pool_reset(struct fc_lport *lport,
1766 struct fc_exch_pool *pool,
1770 struct fc_exch *next;
1772 spin_lock_bh(&pool->lock);
1774 list_for_each_entry_safe(ep, next, &pool->ex_list, ex_list) {
1775 if ((lport == ep->lp) &&
1776 (sid == 0 || sid == ep->sid) &&
1777 (did == 0 || did == ep->did)) {
1779 spin_unlock_bh(&pool->lock);
1783 fc_exch_release(ep);
1784 spin_lock_bh(&pool->lock);
1787 * must restart loop incase while lock
1788 * was down multiple eps were released.
1793 pool->next_index = 0;
1794 pool->left = FC_XID_UNKNOWN;
1795 pool->right = FC_XID_UNKNOWN;
1796 spin_unlock_bh(&pool->lock);
1800 * fc_exch_mgr_reset() - Reset all EMs of a local port
1801 * @lport: The local port whose EMs are to be reset
1802 * @sid: The source ID
1803 * @did: The destination ID
1805 * Reset all EMs associated with a given local port. Release all
1806 * sequences and exchanges. If sid is non-zero then reset only the
1807 * exchanges sent from the local port's FID. If did is non-zero then
1808 * reset only exchanges destined for the local port's FID.
1810 void fc_exch_mgr_reset(struct fc_lport *lport, u32 sid, u32 did)
1812 struct fc_exch_mgr_anchor *ema;
1815 list_for_each_entry(ema, &lport->ema_list, ema_list) {
1816 for_each_possible_cpu(cpu)
1817 fc_exch_pool_reset(lport,
1818 per_cpu_ptr(ema->mp->pool, cpu),
1822 EXPORT_SYMBOL(fc_exch_mgr_reset);
1825 * fc_exch_lookup() - find an exchange
1826 * @lport: The local port
1827 * @xid: The exchange ID
1829 * Returns exchange pointer with hold for caller, or NULL if not found.
1831 static struct fc_exch *fc_exch_lookup(struct fc_lport *lport, u32 xid)
1833 struct fc_exch_mgr_anchor *ema;
1835 list_for_each_entry(ema, &lport->ema_list, ema_list)
1836 if (ema->mp->min_xid <= xid && xid <= ema->mp->max_xid)
1837 return fc_exch_find(ema->mp, xid);
1842 * fc_exch_els_rec() - Handler for ELS REC (Read Exchange Concise) requests
1843 * @rfp: The REC frame, not freed here.
1845 * Note that the requesting port may be different than the S_ID in the request.
1847 static void fc_exch_els_rec(struct fc_frame *rfp)
1849 struct fc_lport *lport;
1850 struct fc_frame *fp;
1852 struct fc_els_rec *rp;
1853 struct fc_els_rec_acc *acc;
1854 enum fc_els_rjt_reason reason = ELS_RJT_LOGIC;
1855 enum fc_els_rjt_explan explan;
1860 lport = fr_dev(rfp);
1861 rp = fc_frame_payload_get(rfp, sizeof(*rp));
1862 explan = ELS_EXPL_INV_LEN;
1865 sid = ntoh24(rp->rec_s_id);
1866 rxid = ntohs(rp->rec_rx_id);
1867 oxid = ntohs(rp->rec_ox_id);
1869 ep = fc_exch_lookup(lport,
1870 sid == fc_host_port_id(lport->host) ? oxid : rxid);
1871 explan = ELS_EXPL_OXID_RXID;
1874 if (ep->oid != sid || oxid != ep->oxid)
1876 if (rxid != FC_XID_UNKNOWN && rxid != ep->rxid)
1878 fp = fc_frame_alloc(lport, sizeof(*acc));
1882 acc = fc_frame_payload_get(fp, sizeof(*acc));
1883 memset(acc, 0, sizeof(*acc));
1884 acc->reca_cmd = ELS_LS_ACC;
1885 acc->reca_ox_id = rp->rec_ox_id;
1886 memcpy(acc->reca_ofid, rp->rec_s_id, 3);
1887 acc->reca_rx_id = htons(ep->rxid);
1888 if (ep->sid == ep->oid)
1889 hton24(acc->reca_rfid, ep->did);
1891 hton24(acc->reca_rfid, ep->sid);
1892 acc->reca_fc4value = htonl(ep->seq.rec_data);
1893 acc->reca_e_stat = htonl(ep->esb_stat & (ESB_ST_RESP |
1896 fc_fill_reply_hdr(fp, rfp, FC_RCTL_ELS_REP, 0);
1897 lport->tt.frame_send(lport, fp);
1899 fc_exch_release(ep);
1903 fc_exch_release(ep);
1905 fc_seq_ls_rjt(rfp, reason, explan);
1909 * fc_exch_rrq_resp() - Handler for RRQ responses
1910 * @sp: The sequence that the RRQ is on
1911 * @fp: The RRQ frame
1912 * @arg: The exchange that the RRQ is on
1914 * TODO: fix error handler.
1916 static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg)
1918 struct fc_exch *aborted_ep = arg;
1922 int err = PTR_ERR(fp);
1924 if (err == -FC_EX_CLOSED || err == -FC_EX_TIMEOUT)
1926 FC_EXCH_DBG(aborted_ep, "Cannot process RRQ, "
1927 "frame error %d\n", err);
1931 op = fc_frame_payload_op(fp);
1936 FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ");
1941 FC_EXCH_DBG(aborted_ep, "unexpected response op %x "
1947 fc_exch_done(&aborted_ep->seq);
1948 /* drop hold for rec qual */
1949 fc_exch_release(aborted_ep);
1954 * fc_exch_seq_send() - Send a frame using a new exchange and sequence
1955 * @lport: The local port to send the frame on
1956 * @fp: The frame to be sent
1957 * @resp: The response handler for this request
1958 * @destructor: The destructor for the exchange
1959 * @arg: The argument to be passed to the response handler
1960 * @timer_msec: The timeout period for the exchange
1962 * The frame pointer with some of the header's fields must be
1963 * filled before calling this routine, those fields are:
1970 * - parameter or relative offset
1972 static struct fc_seq *fc_exch_seq_send(struct fc_lport *lport,
1973 struct fc_frame *fp,
1974 void (*resp)(struct fc_seq *,
1975 struct fc_frame *fp,
1977 void (*destructor)(struct fc_seq *,
1979 void *arg, u32 timer_msec)
1982 struct fc_seq *sp = NULL;
1983 struct fc_frame_header *fh;
1984 struct fc_fcp_pkt *fsp = NULL;
1987 ep = fc_exch_alloc(lport, fp);
1992 ep->esb_stat |= ESB_ST_SEQ_INIT;
1993 fh = fc_frame_header_get(fp);
1994 fc_exch_set_addr(ep, ntoh24(fh->fh_s_id), ntoh24(fh->fh_d_id));
1996 ep->destructor = destructor;
1998 ep->r_a_tov = FC_DEF_R_A_TOV;
2002 ep->fh_type = fh->fh_type; /* save for possbile timeout handling */
2003 ep->f_ctl = ntoh24(fh->fh_f_ctl);
2004 fc_exch_setup_hdr(ep, fp, ep->f_ctl);
2007 if (ep->xid <= lport->lro_xid && fh->fh_r_ctl == FC_RCTL_DD_UNSOL_CMD) {
2009 fc_fcp_ddp_setup(fr_fsp(fp), ep->xid);
2012 if (unlikely(lport->tt.frame_send(lport, fp)))
2016 fc_exch_timer_set_locked(ep, timer_msec);
2017 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not first seq */
2019 if (ep->f_ctl & FC_FC_SEQ_INIT)
2020 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
2021 spin_unlock_bh(&ep->ex_lock);
2025 fc_fcp_ddp_done(fsp);
2026 rc = fc_exch_done_locked(ep);
2027 spin_unlock_bh(&ep->ex_lock);
2034 * fc_exch_rrq() - Send an ELS RRQ (Reinstate Recovery Qualifier) command
2035 * @ep: The exchange to send the RRQ on
2037 * This tells the remote port to stop blocking the use of
2038 * the exchange and the seq_cnt range.
2040 static void fc_exch_rrq(struct fc_exch *ep)
2042 struct fc_lport *lport;
2043 struct fc_els_rrq *rrq;
2044 struct fc_frame *fp;
2049 fp = fc_frame_alloc(lport, sizeof(*rrq));
2053 rrq = fc_frame_payload_get(fp, sizeof(*rrq));
2054 memset(rrq, 0, sizeof(*rrq));
2055 rrq->rrq_cmd = ELS_RRQ;
2056 hton24(rrq->rrq_s_id, ep->sid);
2057 rrq->rrq_ox_id = htons(ep->oxid);
2058 rrq->rrq_rx_id = htons(ep->rxid);
2061 if (ep->esb_stat & ESB_ST_RESP)
2064 fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, did,
2065 lport->port_id, FC_TYPE_ELS,
2066 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
2068 if (fc_exch_seq_send(lport, fp, fc_exch_rrq_resp, NULL, ep,
2073 spin_lock_bh(&ep->ex_lock);
2074 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) {
2075 spin_unlock_bh(&ep->ex_lock);
2076 /* drop hold for rec qual */
2077 fc_exch_release(ep);
2080 ep->esb_stat |= ESB_ST_REC_QUAL;
2081 fc_exch_timer_set_locked(ep, ep->r_a_tov);
2082 spin_unlock_bh(&ep->ex_lock);
2086 * fc_exch_els_rrq() - Handler for ELS RRQ (Reset Recovery Qualifier) requests
2087 * @fp: The RRQ frame, not freed here.
2089 static void fc_exch_els_rrq(struct fc_frame *fp)
2091 struct fc_lport *lport;
2092 struct fc_exch *ep = NULL; /* request or subject exchange */
2093 struct fc_els_rrq *rp;
2096 enum fc_els_rjt_explan explan;
2099 rp = fc_frame_payload_get(fp, sizeof(*rp));
2100 explan = ELS_EXPL_INV_LEN;
2105 * lookup subject exchange.
2107 sid = ntoh24(rp->rrq_s_id); /* subject source */
2108 xid = fc_host_port_id(lport->host) == sid ?
2109 ntohs(rp->rrq_ox_id) : ntohs(rp->rrq_rx_id);
2110 ep = fc_exch_lookup(lport, xid);
2111 explan = ELS_EXPL_OXID_RXID;
2114 spin_lock_bh(&ep->ex_lock);
2115 if (ep->oxid != ntohs(rp->rrq_ox_id))
2117 if (ep->rxid != ntohs(rp->rrq_rx_id) &&
2118 ep->rxid != FC_XID_UNKNOWN)
2120 explan = ELS_EXPL_SID;
2125 * Clear Recovery Qualifier state, and cancel timer if complete.
2127 if (ep->esb_stat & ESB_ST_REC_QUAL) {
2128 ep->esb_stat &= ~ESB_ST_REC_QUAL;
2129 atomic_dec(&ep->ex_refcnt); /* drop hold for rec qual */
2131 if (ep->esb_stat & ESB_ST_COMPLETE) {
2132 if (cancel_delayed_work(&ep->timeout_work))
2133 atomic_dec(&ep->ex_refcnt); /* drop timer hold */
2136 spin_unlock_bh(&ep->ex_lock);
2145 spin_unlock_bh(&ep->ex_lock);
2147 fc_seq_ls_rjt(fp, ELS_RJT_LOGIC, explan);
2150 fc_exch_release(ep); /* drop hold from fc_exch_find */
2154 * fc_exch_update_stats() - update exches stats to lport
2155 * @lport: The local port to update exchange manager stats
2157 void fc_exch_update_stats(struct fc_lport *lport)
2159 struct fc_host_statistics *st;
2160 struct fc_exch_mgr_anchor *ema;
2161 struct fc_exch_mgr *mp;
2163 st = &lport->host_stats;
2165 list_for_each_entry(ema, &lport->ema_list, ema_list) {
2167 st->fc_no_free_exch += atomic_read(&mp->stats.no_free_exch);
2168 st->fc_no_free_exch_xid +=
2169 atomic_read(&mp->stats.no_free_exch_xid);
2170 st->fc_xid_not_found += atomic_read(&mp->stats.xid_not_found);
2171 st->fc_xid_busy += atomic_read(&mp->stats.xid_busy);
2172 st->fc_seq_not_found += atomic_read(&mp->stats.seq_not_found);
2173 st->fc_non_bls_resp += atomic_read(&mp->stats.non_bls_resp);
2176 EXPORT_SYMBOL(fc_exch_update_stats);
2179 * fc_exch_mgr_add() - Add an exchange manager to a local port's list of EMs
2180 * @lport: The local port to add the exchange manager to
2181 * @mp: The exchange manager to be added to the local port
2182 * @match: The match routine that indicates when this EM should be used
2184 struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport,
2185 struct fc_exch_mgr *mp,
2186 bool (*match)(struct fc_frame *))
2188 struct fc_exch_mgr_anchor *ema;
2190 ema = kmalloc(sizeof(*ema), GFP_ATOMIC);
2196 /* add EM anchor to EM anchors list */
2197 list_add_tail(&ema->ema_list, &lport->ema_list);
2198 kref_get(&mp->kref);
2201 EXPORT_SYMBOL(fc_exch_mgr_add);
2204 * fc_exch_mgr_destroy() - Destroy an exchange manager
2205 * @kref: The reference to the EM to be destroyed
2207 static void fc_exch_mgr_destroy(struct kref *kref)
2209 struct fc_exch_mgr *mp = container_of(kref, struct fc_exch_mgr, kref);
2211 mempool_destroy(mp->ep_pool);
2212 free_percpu(mp->pool);
2217 * fc_exch_mgr_del() - Delete an EM from a local port's list
2218 * @ema: The exchange manager anchor identifying the EM to be deleted
2220 void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema)
2222 /* remove EM anchor from EM anchors list */
2223 list_del(&ema->ema_list);
2224 kref_put(&ema->mp->kref, fc_exch_mgr_destroy);
2227 EXPORT_SYMBOL(fc_exch_mgr_del);
2230 * fc_exch_mgr_list_clone() - Share all exchange manager objects
2231 * @src: Source lport to clone exchange managers from
2232 * @dst: New lport that takes references to all the exchange managers
2234 int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst)
2236 struct fc_exch_mgr_anchor *ema, *tmp;
2238 list_for_each_entry(ema, &src->ema_list, ema_list) {
2239 if (!fc_exch_mgr_add(dst, ema->mp, ema->match))
2244 list_for_each_entry_safe(ema, tmp, &dst->ema_list, ema_list)
2245 fc_exch_mgr_del(ema);
2248 EXPORT_SYMBOL(fc_exch_mgr_list_clone);
2251 * fc_exch_mgr_alloc() - Allocate an exchange manager
2252 * @lport: The local port that the new EM will be associated with
2253 * @class: The default FC class for new exchanges
2254 * @min_xid: The minimum XID for exchanges from the new EM
2255 * @max_xid: The maximum XID for exchanges from the new EM
2256 * @match: The match routine for the new EM
2258 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lport,
2259 enum fc_class class,
2260 u16 min_xid, u16 max_xid,
2261 bool (*match)(struct fc_frame *))
2263 struct fc_exch_mgr *mp;
2264 u16 pool_exch_range;
2267 struct fc_exch_pool *pool;
2269 if (max_xid <= min_xid || max_xid == FC_XID_UNKNOWN ||
2270 (min_xid & fc_cpu_mask) != 0) {
2271 FC_LPORT_DBG(lport, "Invalid min_xid 0x:%x and max_xid 0x:%x\n",
2277 * allocate memory for EM
2279 mp = kzalloc(sizeof(struct fc_exch_mgr), GFP_ATOMIC);
2284 /* adjust em exch xid range for offload */
2285 mp->min_xid = min_xid;
2287 /* reduce range so per cpu pool fits into PCPU_MIN_UNIT_SIZE pool */
2288 pool_exch_range = (PCPU_MIN_UNIT_SIZE - sizeof(*pool)) /
2289 sizeof(struct fc_exch *);
2290 if ((max_xid - min_xid + 1) / (fc_cpu_mask + 1) > pool_exch_range) {
2291 mp->max_xid = pool_exch_range * (fc_cpu_mask + 1) +
2294 mp->max_xid = max_xid;
2295 pool_exch_range = (mp->max_xid - mp->min_xid + 1) /
2299 mp->ep_pool = mempool_create_slab_pool(2, fc_em_cachep);
2304 * Setup per cpu exch pool with entire exchange id range equally
2305 * divided across all cpus. The exch pointers array memory is
2306 * allocated for exch range per pool.
2308 mp->pool_max_index = pool_exch_range - 1;
2311 * Allocate and initialize per cpu exch pool
2313 pool_size = sizeof(*pool) + pool_exch_range * sizeof(struct fc_exch *);
2314 mp->pool = __alloc_percpu(pool_size, __alignof__(struct fc_exch_pool));
2317 for_each_possible_cpu(cpu) {
2318 pool = per_cpu_ptr(mp->pool, cpu);
2319 pool->next_index = 0;
2320 pool->left = FC_XID_UNKNOWN;
2321 pool->right = FC_XID_UNKNOWN;
2322 spin_lock_init(&pool->lock);
2323 INIT_LIST_HEAD(&pool->ex_list);
2326 kref_init(&mp->kref);
2327 if (!fc_exch_mgr_add(lport, mp, match)) {
2328 free_percpu(mp->pool);
2333 * Above kref_init() sets mp->kref to 1 and then
2334 * call to fc_exch_mgr_add incremented mp->kref again,
2335 * so adjust that extra increment.
2337 kref_put(&mp->kref, fc_exch_mgr_destroy);
2341 mempool_destroy(mp->ep_pool);
2346 EXPORT_SYMBOL(fc_exch_mgr_alloc);
2349 * fc_exch_mgr_free() - Free all exchange managers on a local port
2350 * @lport: The local port whose EMs are to be freed
2352 void fc_exch_mgr_free(struct fc_lport *lport)
2354 struct fc_exch_mgr_anchor *ema, *next;
2356 flush_workqueue(fc_exch_workqueue);
2357 list_for_each_entry_safe(ema, next, &lport->ema_list, ema_list)
2358 fc_exch_mgr_del(ema);
2360 EXPORT_SYMBOL(fc_exch_mgr_free);
2363 * fc_find_ema() - Lookup and return appropriate Exchange Manager Anchor depending
2366 * @lport: The local port the frame was received on
2367 * @fh: The received frame header
2369 static struct fc_exch_mgr_anchor *fc_find_ema(u32 f_ctl,
2370 struct fc_lport *lport,
2371 struct fc_frame_header *fh)
2373 struct fc_exch_mgr_anchor *ema;
2376 if (f_ctl & FC_FC_EX_CTX)
2377 xid = ntohs(fh->fh_ox_id);
2379 xid = ntohs(fh->fh_rx_id);
2380 if (xid == FC_XID_UNKNOWN)
2381 return list_entry(lport->ema_list.prev,
2382 typeof(*ema), ema_list);
2385 list_for_each_entry(ema, &lport->ema_list, ema_list) {
2386 if ((xid >= ema->mp->min_xid) &&
2387 (xid <= ema->mp->max_xid))
2393 * fc_exch_recv() - Handler for received frames
2394 * @lport: The local port the frame was received on
2395 * @fp: The received frame
2397 void fc_exch_recv(struct fc_lport *lport, struct fc_frame *fp)
2399 struct fc_frame_header *fh = fc_frame_header_get(fp);
2400 struct fc_exch_mgr_anchor *ema;
2404 if (!lport || lport->state == LPORT_ST_DISABLED) {
2405 FC_LPORT_DBG(lport, "Receiving frames for an lport that "
2406 "has not been initialized correctly\n");
2411 f_ctl = ntoh24(fh->fh_f_ctl);
2412 ema = fc_find_ema(f_ctl, lport, fh);
2414 FC_LPORT_DBG(lport, "Unable to find Exchange Manager Anchor,"
2415 "fc_ctl <0x%x>, xid <0x%x>\n",
2417 (f_ctl & FC_FC_EX_CTX) ?
2418 ntohs(fh->fh_ox_id) :
2419 ntohs(fh->fh_rx_id));
2425 * If frame is marked invalid, just drop it.
2427 switch (fr_eof(fp)) {
2429 if (f_ctl & FC_FC_END_SEQ)
2430 skb_trim(fp_skb(fp), fr_len(fp) - FC_FC_FILL(f_ctl));
2433 if (fh->fh_type == FC_TYPE_BLS)
2434 fc_exch_recv_bls(ema->mp, fp);
2435 else if ((f_ctl & (FC_FC_EX_CTX | FC_FC_SEQ_CTX)) ==
2437 fc_exch_recv_seq_resp(ema->mp, fp);
2438 else if (f_ctl & FC_FC_SEQ_CTX)
2439 fc_exch_recv_resp(ema->mp, fp);
2440 else /* no EX_CTX and no SEQ_CTX */
2441 fc_exch_recv_req(lport, ema->mp, fp);
2444 FC_LPORT_DBG(lport, "dropping invalid frame (eof %x)",
2449 EXPORT_SYMBOL(fc_exch_recv);
2452 * fc_exch_init() - Initialize the exchange layer for a local port
2453 * @lport: The local port to initialize the exchange layer for
2455 int fc_exch_init(struct fc_lport *lport)
2457 if (!lport->tt.seq_start_next)
2458 lport->tt.seq_start_next = fc_seq_start_next;
2460 if (!lport->tt.seq_set_resp)
2461 lport->tt.seq_set_resp = fc_seq_set_resp;
2463 if (!lport->tt.exch_seq_send)
2464 lport->tt.exch_seq_send = fc_exch_seq_send;
2466 if (!lport->tt.seq_send)
2467 lport->tt.seq_send = fc_seq_send;
2469 if (!lport->tt.seq_els_rsp_send)
2470 lport->tt.seq_els_rsp_send = fc_seq_els_rsp_send;
2472 if (!lport->tt.exch_done)
2473 lport->tt.exch_done = fc_exch_done;
2475 if (!lport->tt.exch_mgr_reset)
2476 lport->tt.exch_mgr_reset = fc_exch_mgr_reset;
2478 if (!lport->tt.seq_exch_abort)
2479 lport->tt.seq_exch_abort = fc_seq_exch_abort;
2481 if (!lport->tt.seq_assign)
2482 lport->tt.seq_assign = fc_seq_assign;
2484 if (!lport->tt.seq_release)
2485 lport->tt.seq_release = fc_seq_release;
2489 EXPORT_SYMBOL(fc_exch_init);
2492 * fc_setup_exch_mgr() - Setup an exchange manager
2494 int fc_setup_exch_mgr(void)
2496 fc_em_cachep = kmem_cache_create("libfc_em", sizeof(struct fc_exch),
2497 0, SLAB_HWCACHE_ALIGN, NULL);
2502 * Initialize fc_cpu_mask and fc_cpu_order. The
2503 * fc_cpu_mask is set for nr_cpu_ids rounded up
2504 * to order of 2's * power and order is stored
2505 * in fc_cpu_order as this is later required in
2506 * mapping between an exch id and exch array index
2507 * in per cpu exch pool.
2509 * This round up is required to align fc_cpu_mask
2510 * to exchange id's lower bits such that all incoming
2511 * frames of an exchange gets delivered to the same
2512 * cpu on which exchange originated by simple bitwise
2513 * AND operation between fc_cpu_mask and exchange id.
2517 while (fc_cpu_mask < nr_cpu_ids) {
2523 fc_exch_workqueue = create_singlethread_workqueue("fc_exch_workqueue");
2524 if (!fc_exch_workqueue)
2528 kmem_cache_destroy(fc_em_cachep);
2533 * fc_destroy_exch_mgr() - Destroy an exchange manager
2535 void fc_destroy_exch_mgr(void)
2537 destroy_workqueue(fc_exch_workqueue);
2538 kmem_cache_destroy(fc_em_cachep);