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/gfp.h>
28 #include <linux/err.h>
30 #include <scsi/fc/fc_fc2.h>
32 #include <scsi/libfc.h>
33 #include <scsi/fc_encode.h>
35 static struct kmem_cache *fc_em_cachep; /* cache for exchanges */
38 * Structure and function definitions for managing Fibre Channel Exchanges
41 * The three primary structures used here are fc_exch_mgr, fc_exch, and fc_seq.
43 * fc_exch_mgr holds the exchange state for an N port
45 * fc_exch holds state for one exchange and links to its active sequence.
47 * fc_seq holds the state for an individual sequence.
53 * This structure is the center for creating exchanges and sequences.
54 * It manages the allocation of exchange IDs.
57 enum fc_class class; /* default class for sequences */
58 spinlock_t em_lock; /* exchange manager lock,
59 must be taken before ex_lock */
60 u16 last_xid; /* last allocated exchange ID */
61 u16 min_xid; /* min exchange ID */
62 u16 max_xid; /* max exchange ID */
63 u16 max_read; /* max exchange ID for read */
64 u16 last_read; /* last xid allocated for read */
65 u32 total_exches; /* total allocated exchanges */
66 struct list_head ex_list; /* allocated exchanges list */
67 struct fc_lport *lp; /* fc device instance */
68 mempool_t *ep_pool; /* reserve ep's */
71 * currently exchange mgr stats are updated but not used.
72 * either stats can be expose via sysfs or remove them
73 * all together if not used XXX
76 atomic_t no_free_exch;
77 atomic_t no_free_exch_xid;
78 atomic_t xid_not_found;
80 atomic_t seq_not_found;
81 atomic_t non_bls_resp;
83 struct fc_exch **exches; /* for exch pointers indexed by xid */
85 #define fc_seq_exch(sp) container_of(sp, struct fc_exch, seq)
87 static void fc_exch_rrq(struct fc_exch *);
88 static void fc_seq_ls_acc(struct fc_seq *);
89 static void fc_seq_ls_rjt(struct fc_seq *, enum fc_els_rjt_reason,
90 enum fc_els_rjt_explan);
91 static void fc_exch_els_rec(struct fc_seq *, struct fc_frame *);
92 static void fc_exch_els_rrq(struct fc_seq *, struct fc_frame *);
93 static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp);
96 * Internal implementation notes.
98 * The exchange manager is one by default in libfc but LLD may choose
99 * to have one per CPU. The sequence manager is one per exchange manager
100 * and currently never separated.
102 * Section 9.8 in FC-FS-2 specifies: "The SEQ_ID is a one-byte field
103 * assigned by the Sequence Initiator that shall be unique for a specific
104 * D_ID and S_ID pair while the Sequence is open." Note that it isn't
105 * qualified by exchange ID, which one might think it would be.
106 * In practice this limits the number of open sequences and exchanges to 256
107 * per session. For most targets we could treat this limit as per exchange.
109 * The exchange and its sequence are freed when the last sequence is received.
110 * It's possible for the remote port to leave an exchange open without
111 * sending any sequences.
113 * Notes on reference counts:
115 * Exchanges are reference counted and exchange gets freed when the reference
116 * count becomes zero.
119 * Sequences are timed out for E_D_TOV and R_A_TOV.
121 * Sequence event handling:
123 * The following events may occur on initiator sequences:
126 * For now, the whole thing is sent.
128 * This applies only to class F.
129 * The sequence is marked complete.
131 * The upper layer calls fc_exch_done() when done
132 * with exchange and sequence tuple.
133 * RX-inferred completion.
134 * When we receive the next sequence on the same exchange, we can
135 * retire the previous sequence ID. (XXX not implemented).
137 * R_A_TOV frees the sequence ID. If we're waiting for ACK,
138 * E_D_TOV causes abort and calls upper layer response handler
139 * with FC_EX_TIMEOUT error.
145 * The following events may occur on recipient sequences:
148 * Allocate sequence for first frame received.
149 * Hold during receive handler.
150 * Release when final frame received.
151 * Keep status of last N of these for the ELS RES command. XXX TBD.
153 * Deallocate sequence
157 * For now, we neglect conditions where only part of a sequence was
158 * received or transmitted, or where out-of-order receipt is detected.
164 * The EM code run in a per-CPU worker thread.
166 * To protect against concurrency between a worker thread code and timers,
167 * sequence allocation and deallocation must be locked.
168 * - exchange refcnt can be done atomicly without locks.
169 * - sequence allocation must be locked by exch lock.
170 * - If the em_lock and ex_lock must be taken at the same time, then the
171 * em_lock must be taken before the ex_lock.
175 * opcode names for debugging.
177 static char *fc_exch_rctl_names[] = FC_RCTL_NAMES_INIT;
179 #define FC_TABLE_SIZE(x) (sizeof(x) / sizeof(x[0]))
181 static inline const char *fc_exch_name_lookup(unsigned int op, char **table,
182 unsigned int max_index)
184 const char *name = NULL;
193 static const char *fc_exch_rctl_name(unsigned int op)
195 return fc_exch_name_lookup(op, fc_exch_rctl_names,
196 FC_TABLE_SIZE(fc_exch_rctl_names));
200 * Hold an exchange - keep it from being freed.
202 static void fc_exch_hold(struct fc_exch *ep)
204 atomic_inc(&ep->ex_refcnt);
208 * setup fc hdr by initializing few more FC header fields and sof/eof.
209 * Initialized fields by this func:
210 * - fh_ox_id, fh_rx_id, fh_seq_id, fh_seq_cnt
213 static void fc_exch_setup_hdr(struct fc_exch *ep, struct fc_frame *fp,
216 struct fc_frame_header *fh = fc_frame_header_get(fp);
219 fr_sof(fp) = ep->class;
221 fr_sof(fp) = fc_sof_normal(ep->class);
223 if (f_ctl & FC_FC_END_SEQ) {
224 fr_eof(fp) = FC_EOF_T;
225 if (fc_sof_needs_ack(ep->class))
226 fr_eof(fp) = FC_EOF_N;
229 * The number of fill bytes to make the length a 4-byte
230 * multiple is the low order 2-bits of the f_ctl.
231 * The fill itself will have been cleared by the frame
233 * After this, the length will be even, as expected by
236 fill = fr_len(fp) & 3;
239 /* TODO, this may be a problem with fragmented skb */
240 skb_put(fp_skb(fp), fill);
241 hton24(fh->fh_f_ctl, f_ctl | fill);
244 WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */
245 fr_eof(fp) = FC_EOF_N;
249 * Initialize remainig fh fields
250 * from fc_fill_fc_hdr
252 fh->fh_ox_id = htons(ep->oxid);
253 fh->fh_rx_id = htons(ep->rxid);
254 fh->fh_seq_id = ep->seq.id;
255 fh->fh_seq_cnt = htons(ep->seq.cnt);
260 * Release a reference to an exchange.
261 * If the refcnt goes to zero and the exchange is complete, it is freed.
263 static void fc_exch_release(struct fc_exch *ep)
265 struct fc_exch_mgr *mp;
267 if (atomic_dec_and_test(&ep->ex_refcnt)) {
270 ep->destructor(&ep->seq, ep->arg);
271 if (ep->lp->tt.exch_put)
272 ep->lp->tt.exch_put(ep->lp, mp, ep->xid);
273 WARN_ON(!(ep->esb_stat & ESB_ST_COMPLETE));
274 mempool_free(ep, mp->ep_pool);
278 static int fc_exch_done_locked(struct fc_exch *ep)
283 * We must check for completion in case there are two threads
284 * tyring to complete this. But the rrq code will reuse the
285 * ep, and in that case we only clear the resp and set it as
286 * complete, so it can be reused by the timer to send the rrq.
289 if (ep->state & FC_EX_DONE)
291 ep->esb_stat |= ESB_ST_COMPLETE;
293 if (!(ep->esb_stat & ESB_ST_REC_QUAL)) {
294 ep->state |= FC_EX_DONE;
295 if (cancel_delayed_work(&ep->timeout_work))
296 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */
302 static void fc_exch_mgr_delete_ep(struct fc_exch *ep)
304 struct fc_exch_mgr *mp;
307 spin_lock_bh(&mp->em_lock);
308 WARN_ON(mp->total_exches <= 0);
310 mp->exches[ep->xid - mp->min_xid] = NULL;
311 list_del(&ep->ex_list);
312 spin_unlock_bh(&mp->em_lock);
313 fc_exch_release(ep); /* drop hold for exch in mp */
317 * Internal version of fc_exch_timer_set - used with lock held.
319 static inline void fc_exch_timer_set_locked(struct fc_exch *ep,
320 unsigned int timer_msec)
322 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
325 FC_EXCH_DBG(ep, "Exchange timed out, notifying the upper layer\n");
327 if (schedule_delayed_work(&ep->timeout_work,
328 msecs_to_jiffies(timer_msec)))
329 fc_exch_hold(ep); /* hold for timer */
333 * Set timer for an exchange.
334 * The time is a minimum delay in milliseconds until the timer fires.
335 * Used for upper level protocols to time out the exchange.
336 * The timer is cancelled when it fires or when the exchange completes.
337 * Returns non-zero if a timer couldn't be allocated.
339 static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec)
341 spin_lock_bh(&ep->ex_lock);
342 fc_exch_timer_set_locked(ep, timer_msec);
343 spin_unlock_bh(&ep->ex_lock);
346 int fc_seq_exch_abort(const struct fc_seq *req_sp, unsigned int timer_msec)
353 ep = fc_seq_exch(req_sp);
355 spin_lock_bh(&ep->ex_lock);
356 if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL) ||
357 ep->state & (FC_EX_DONE | FC_EX_RST_CLEANUP)) {
358 spin_unlock_bh(&ep->ex_lock);
363 * Send the abort on a new sequence if possible.
365 sp = fc_seq_start_next_locked(&ep->seq);
367 spin_unlock_bh(&ep->ex_lock);
371 ep->esb_stat |= ESB_ST_SEQ_INIT | ESB_ST_ABNORMAL;
373 fc_exch_timer_set_locked(ep, timer_msec);
374 spin_unlock_bh(&ep->ex_lock);
377 * If not logged into the fabric, don't send ABTS but leave
378 * sequence active until next timeout.
384 * Send an abort for the sequence that timed out.
386 fp = fc_frame_alloc(ep->lp, 0);
388 fc_fill_fc_hdr(fp, FC_RCTL_BA_ABTS, ep->did, ep->sid,
389 FC_TYPE_BLS, FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
390 error = fc_seq_send(ep->lp, sp, fp);
395 EXPORT_SYMBOL(fc_seq_exch_abort);
398 * Exchange timeout - handle exchange timer expiration.
399 * The timer will have been cancelled before this is called.
401 static void fc_exch_timeout(struct work_struct *work)
403 struct fc_exch *ep = container_of(work, struct fc_exch,
405 struct fc_seq *sp = &ep->seq;
406 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
411 spin_lock_bh(&ep->ex_lock);
412 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE))
415 e_stat = ep->esb_stat;
416 if (e_stat & ESB_ST_COMPLETE) {
417 ep->esb_stat = e_stat & ~ESB_ST_REC_QUAL;
418 spin_unlock_bh(&ep->ex_lock);
419 if (e_stat & ESB_ST_REC_QUAL)
426 if (e_stat & ESB_ST_ABNORMAL)
427 rc = fc_exch_done_locked(ep);
428 spin_unlock_bh(&ep->ex_lock);
430 fc_exch_mgr_delete_ep(ep);
432 resp(sp, ERR_PTR(-FC_EX_TIMEOUT), arg);
433 fc_seq_exch_abort(sp, 2 * ep->r_a_tov);
437 spin_unlock_bh(&ep->ex_lock);
440 * This release matches the hold taken when the timer was set.
446 * Allocate a sequence.
448 * We don't support multiple originated sequences on the same exchange.
449 * By implication, any previously originated sequence on this exchange
450 * is complete, and we reallocate the same sequence.
452 static struct fc_seq *fc_seq_alloc(struct fc_exch *ep, u8 seq_id)
464 * fc_em_alloc_xid - returns an xid based on request type
465 * @lp : ptr to associated lport
466 * @fp : ptr to the assocated frame
468 * check the associated fc_fsp_pkt to get scsi command type and
469 * command direction to decide from which range this exch id
470 * will be allocated from.
472 * Returns : 0 or an valid xid
474 static u16 fc_em_alloc_xid(struct fc_exch_mgr *mp, const struct fc_frame *fp)
478 struct fc_exch *ep = NULL;
481 if (fc_fcp_is_read(fr_fsp(fp))) {
484 plast = &mp->last_read;
486 min = mp->max_read + 1;
488 plast = &mp->last_xid;
493 plast = &mp->last_xid;
497 xid = (xid == max) ? min : xid + 1;
498 ep = mp->exches[xid - mp->min_xid];
499 } while ((ep != NULL) && (xid != *plast));
510 * fc_exch_alloc - allocate an exchange.
511 * @mp : ptr to the exchange manager
514 * if xid is supplied zero then assign next free exchange ID
515 * from exchange manager, otherwise use supplied xid.
516 * Returns with exch lock held.
518 struct fc_exch *fc_exch_alloc(struct fc_exch_mgr *mp,
519 struct fc_frame *fp, u16 xid)
523 /* allocate memory for exchange */
524 ep = mempool_alloc(mp->ep_pool, GFP_ATOMIC);
526 atomic_inc(&mp->stats.no_free_exch);
529 memset(ep, 0, sizeof(*ep));
531 spin_lock_bh(&mp->em_lock);
532 /* alloc xid if input xid 0 */
534 /* alloc a new xid */
535 xid = fc_em_alloc_xid(mp, fp);
537 printk(KERN_WARNING "libfc: Failed to allocate an exhange\n");
542 fc_exch_hold(ep); /* hold for exch in mp */
543 spin_lock_init(&ep->ex_lock);
545 * Hold exch lock for caller to prevent fc_exch_reset()
546 * from releasing exch while fc_exch_alloc() caller is
547 * still working on exch.
549 spin_lock_bh(&ep->ex_lock);
551 mp->exches[xid - mp->min_xid] = ep;
552 list_add_tail(&ep->ex_list, &mp->ex_list);
553 fc_seq_alloc(ep, ep->seq_id++);
555 spin_unlock_bh(&mp->em_lock);
560 ep->oxid = ep->xid = xid;
563 ep->f_ctl = FC_FC_FIRST_SEQ; /* next seq is first seq */
564 ep->rxid = FC_XID_UNKNOWN;
565 ep->class = mp->class;
566 INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout);
570 spin_unlock_bh(&mp->em_lock);
571 atomic_inc(&mp->stats.no_free_exch_xid);
572 mempool_free(ep, mp->ep_pool);
575 EXPORT_SYMBOL(fc_exch_alloc);
578 * Lookup and hold an exchange.
580 static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid)
582 struct fc_exch *ep = NULL;
584 if ((xid >= mp->min_xid) && (xid <= mp->max_xid)) {
585 spin_lock_bh(&mp->em_lock);
586 ep = mp->exches[xid - mp->min_xid];
589 WARN_ON(ep->xid != xid);
591 spin_unlock_bh(&mp->em_lock);
596 void fc_exch_done(struct fc_seq *sp)
598 struct fc_exch *ep = fc_seq_exch(sp);
601 spin_lock_bh(&ep->ex_lock);
602 rc = fc_exch_done_locked(ep);
603 spin_unlock_bh(&ep->ex_lock);
605 fc_exch_mgr_delete_ep(ep);
607 EXPORT_SYMBOL(fc_exch_done);
610 * Allocate a new exchange as responder.
611 * Sets the responder ID in the frame header.
613 static struct fc_exch *fc_exch_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
616 struct fc_frame_header *fh;
618 ep = mp->lp->tt.exch_get(mp->lp, fp);
620 ep->class = fc_frame_class(fp);
623 * Set EX_CTX indicating we're responding on this exchange.
625 ep->f_ctl |= FC_FC_EX_CTX; /* we're responding */
626 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not new */
627 fh = fc_frame_header_get(fp);
628 ep->sid = ntoh24(fh->fh_d_id);
629 ep->did = ntoh24(fh->fh_s_id);
633 * Allocated exchange has placed the XID in the
634 * originator field. Move it to the responder field,
635 * and set the originator XID from the frame.
638 ep->oxid = ntohs(fh->fh_ox_id);
639 ep->esb_stat |= ESB_ST_RESP | ESB_ST_SEQ_INIT;
640 if ((ntoh24(fh->fh_f_ctl) & FC_FC_SEQ_INIT) == 0)
641 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
643 fc_exch_hold(ep); /* hold for caller */
644 spin_unlock_bh(&ep->ex_lock); /* lock from exch_get */
650 * Find a sequence for receive where the other end is originating the sequence.
651 * If fc_pf_rjt_reason is FC_RJT_NONE then this function will have a hold
652 * on the ep that should be released by the caller.
654 static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_exch_mgr *mp,
657 struct fc_frame_header *fh = fc_frame_header_get(fp);
658 struct fc_exch *ep = NULL;
659 struct fc_seq *sp = NULL;
660 enum fc_pf_rjt_reason reject = FC_RJT_NONE;
664 f_ctl = ntoh24(fh->fh_f_ctl);
665 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != 0);
668 * Lookup or create the exchange if we will be creating the sequence.
670 if (f_ctl & FC_FC_EX_CTX) {
671 xid = ntohs(fh->fh_ox_id); /* we originated exch */
672 ep = fc_exch_find(mp, xid);
674 atomic_inc(&mp->stats.xid_not_found);
675 reject = FC_RJT_OX_ID;
678 if (ep->rxid == FC_XID_UNKNOWN)
679 ep->rxid = ntohs(fh->fh_rx_id);
680 else if (ep->rxid != ntohs(fh->fh_rx_id)) {
681 reject = FC_RJT_OX_ID;
685 xid = ntohs(fh->fh_rx_id); /* we are the responder */
688 * Special case for MDS issuing an ELS TEST with a
690 * XXX take this out once we do the proper reject.
692 if (xid == 0 && fh->fh_r_ctl == FC_RCTL_ELS_REQ &&
693 fc_frame_payload_op(fp) == ELS_TEST) {
694 fh->fh_rx_id = htons(FC_XID_UNKNOWN);
695 xid = FC_XID_UNKNOWN;
699 * new sequence - find the exchange
701 ep = fc_exch_find(mp, xid);
702 if ((f_ctl & FC_FC_FIRST_SEQ) && fc_sof_is_init(fr_sof(fp))) {
704 atomic_inc(&mp->stats.xid_busy);
705 reject = FC_RJT_RX_ID;
708 ep = fc_exch_resp(mp, fp);
710 reject = FC_RJT_EXCH_EST; /* XXX */
713 xid = ep->xid; /* get our XID */
715 atomic_inc(&mp->stats.xid_not_found);
716 reject = FC_RJT_RX_ID; /* XID not found */
722 * At this point, we have the exchange held.
723 * Find or create the sequence.
725 if (fc_sof_is_init(fr_sof(fp))) {
726 sp = fc_seq_start_next(&ep->seq);
728 reject = FC_RJT_SEQ_XS; /* exchange shortage */
731 sp->id = fh->fh_seq_id;
732 sp->ssb_stat |= SSB_ST_RESP;
735 if (sp->id != fh->fh_seq_id) {
736 atomic_inc(&mp->stats.seq_not_found);
737 reject = FC_RJT_SEQ_ID; /* sequence/exch should exist */
741 WARN_ON(ep != fc_seq_exch(sp));
743 if (f_ctl & FC_FC_SEQ_INIT)
744 ep->esb_stat |= ESB_ST_SEQ_INIT;
750 fc_exch_done(&ep->seq);
751 fc_exch_release(ep); /* hold from fc_exch_find/fc_exch_resp */
756 * Find the sequence for a frame being received.
757 * We originated the sequence, so it should be found.
758 * We may or may not have originated the exchange.
759 * Does not hold the sequence for the caller.
761 static struct fc_seq *fc_seq_lookup_orig(struct fc_exch_mgr *mp,
764 struct fc_frame_header *fh = fc_frame_header_get(fp);
766 struct fc_seq *sp = NULL;
770 f_ctl = ntoh24(fh->fh_f_ctl);
771 WARN_ON((f_ctl & FC_FC_SEQ_CTX) != FC_FC_SEQ_CTX);
772 xid = ntohs((f_ctl & FC_FC_EX_CTX) ? fh->fh_ox_id : fh->fh_rx_id);
773 ep = fc_exch_find(mp, xid);
776 if (ep->seq.id == fh->fh_seq_id) {
778 * Save the RX_ID if we didn't previously know it.
781 if ((f_ctl & FC_FC_EX_CTX) != 0 &&
782 ep->rxid == FC_XID_UNKNOWN) {
783 ep->rxid = ntohs(fh->fh_rx_id);
791 * Set addresses for an exchange.
792 * Note this must be done before the first sequence of the exchange is sent.
794 static void fc_exch_set_addr(struct fc_exch *ep,
795 u32 orig_id, u32 resp_id)
798 if (ep->esb_stat & ESB_ST_RESP) {
807 static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp)
809 struct fc_exch *ep = fc_seq_exch(sp);
811 sp = fc_seq_alloc(ep, ep->seq_id++);
812 FC_EXCH_DBG(ep, "f_ctl %6x seq %2x\n",
817 * Allocate a new sequence on the same exchange as the supplied sequence.
818 * This will never return NULL.
820 struct fc_seq *fc_seq_start_next(struct fc_seq *sp)
822 struct fc_exch *ep = fc_seq_exch(sp);
824 spin_lock_bh(&ep->ex_lock);
825 WARN_ON((ep->esb_stat & ESB_ST_COMPLETE) != 0);
826 sp = fc_seq_start_next_locked(sp);
827 spin_unlock_bh(&ep->ex_lock);
831 EXPORT_SYMBOL(fc_seq_start_next);
833 int fc_seq_send(struct fc_lport *lp, struct fc_seq *sp, struct fc_frame *fp)
836 struct fc_frame_header *fh = fc_frame_header_get(fp);
840 ep = fc_seq_exch(sp);
841 WARN_ON((ep->esb_stat & ESB_ST_SEQ_INIT) != ESB_ST_SEQ_INIT);
843 f_ctl = ntoh24(fh->fh_f_ctl);
844 fc_exch_setup_hdr(ep, fp, f_ctl);
847 * update sequence count if this frame is carrying
848 * multiple FC frames when sequence offload is enabled
851 if (fr_max_payload(fp))
852 sp->cnt += DIV_ROUND_UP((fr_len(fp) - sizeof(*fh)),
860 error = lp->tt.frame_send(lp, fp);
863 * Update the exchange and sequence flags,
864 * assuming all frames for the sequence have been sent.
865 * We can only be called to send once for each sequence.
867 spin_lock_bh(&ep->ex_lock);
868 ep->f_ctl = f_ctl & ~FC_FC_FIRST_SEQ; /* not first seq */
869 if (f_ctl & (FC_FC_END_SEQ | FC_FC_SEQ_INIT))
870 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
871 spin_unlock_bh(&ep->ex_lock);
874 EXPORT_SYMBOL(fc_seq_send);
876 void fc_seq_els_rsp_send(struct fc_seq *sp, enum fc_els_cmd els_cmd,
877 struct fc_seq_els_data *els_data)
881 fc_seq_ls_rjt(sp, els_data->reason, els_data->explan);
887 fc_exch_els_rrq(sp, els_data->fp);
890 fc_exch_els_rec(sp, els_data->fp);
893 FC_EXCH_DBG(fc_seq_exch(sp), "Invalid ELS CMD:%x\n", els_cmd);
896 EXPORT_SYMBOL(fc_seq_els_rsp_send);
899 * Send a sequence, which is also the last sequence in the exchange.
901 static void fc_seq_send_last(struct fc_seq *sp, struct fc_frame *fp,
902 enum fc_rctl rctl, enum fc_fh_type fh_type)
905 struct fc_exch *ep = fc_seq_exch(sp);
907 f_ctl = FC_FC_LAST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT;
909 fc_fill_fc_hdr(fp, rctl, ep->did, ep->sid, fh_type, f_ctl, 0);
910 fc_seq_send(ep->lp, sp, fp);
914 * Send ACK_1 (or equiv.) indicating we received something.
915 * The frame we're acking is supplied.
917 static void fc_seq_send_ack(struct fc_seq *sp, const struct fc_frame *rx_fp)
920 struct fc_frame_header *rx_fh;
921 struct fc_frame_header *fh;
922 struct fc_exch *ep = fc_seq_exch(sp);
923 struct fc_lport *lp = ep->lp;
927 * Don't send ACKs for class 3.
929 if (fc_sof_needs_ack(fr_sof(rx_fp))) {
930 fp = fc_frame_alloc(lp, 0);
934 fh = fc_frame_header_get(fp);
935 fh->fh_r_ctl = FC_RCTL_ACK_1;
936 fh->fh_type = FC_TYPE_BLS;
939 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
940 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
941 * Bits 9-8 are meaningful (retransmitted or unidirectional).
942 * Last ACK uses bits 7-6 (continue sequence),
943 * bits 5-4 are meaningful (what kind of ACK to use).
945 rx_fh = fc_frame_header_get(rx_fp);
946 f_ctl = ntoh24(rx_fh->fh_f_ctl);
947 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
948 FC_FC_FIRST_SEQ | FC_FC_LAST_SEQ |
949 FC_FC_END_SEQ | FC_FC_END_CONN | FC_FC_SEQ_INIT |
950 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
951 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
952 hton24(fh->fh_f_ctl, f_ctl);
954 fc_exch_setup_hdr(ep, fp, f_ctl);
955 fh->fh_seq_id = rx_fh->fh_seq_id;
956 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
957 fh->fh_parm_offset = htonl(1); /* ack single frame */
959 fr_sof(fp) = fr_sof(rx_fp);
960 if (f_ctl & FC_FC_END_SEQ)
961 fr_eof(fp) = FC_EOF_T;
963 fr_eof(fp) = FC_EOF_N;
965 (void) lp->tt.frame_send(lp, fp);
971 * This is for rejecting BA_ABTS only.
973 static void fc_exch_send_ba_rjt(struct fc_frame *rx_fp,
974 enum fc_ba_rjt_reason reason,
975 enum fc_ba_rjt_explan explan)
978 struct fc_frame_header *rx_fh;
979 struct fc_frame_header *fh;
980 struct fc_ba_rjt *rp;
985 fp = fc_frame_alloc(lp, sizeof(*rp));
988 fh = fc_frame_header_get(fp);
989 rx_fh = fc_frame_header_get(rx_fp);
991 memset(fh, 0, sizeof(*fh) + sizeof(*rp));
993 rp = fc_frame_payload_get(fp, sizeof(*rp));
994 rp->br_reason = reason;
995 rp->br_explan = explan;
998 * seq_id, cs_ctl, df_ctl and param/offset are zero.
1000 memcpy(fh->fh_s_id, rx_fh->fh_d_id, 3);
1001 memcpy(fh->fh_d_id, rx_fh->fh_s_id, 3);
1002 fh->fh_ox_id = rx_fh->fh_rx_id;
1003 fh->fh_rx_id = rx_fh->fh_ox_id;
1004 fh->fh_seq_cnt = rx_fh->fh_seq_cnt;
1005 fh->fh_r_ctl = FC_RCTL_BA_RJT;
1006 fh->fh_type = FC_TYPE_BLS;
1009 * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22).
1010 * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT.
1011 * Bits 9-8 are meaningful (retransmitted or unidirectional).
1012 * Last ACK uses bits 7-6 (continue sequence),
1013 * bits 5-4 are meaningful (what kind of ACK to use).
1014 * Always set LAST_SEQ, END_SEQ.
1016 f_ctl = ntoh24(rx_fh->fh_f_ctl);
1017 f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX |
1018 FC_FC_END_CONN | FC_FC_SEQ_INIT |
1019 FC_FC_RETX_SEQ | FC_FC_UNI_TX;
1020 f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX;
1021 f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ;
1022 f_ctl &= ~FC_FC_FIRST_SEQ;
1023 hton24(fh->fh_f_ctl, f_ctl);
1025 fr_sof(fp) = fc_sof_class(fr_sof(rx_fp));
1026 fr_eof(fp) = FC_EOF_T;
1027 if (fc_sof_needs_ack(fr_sof(fp)))
1028 fr_eof(fp) = FC_EOF_N;
1030 (void) lp->tt.frame_send(lp, fp);
1034 * Handle an incoming ABTS. This would be for target mode usually,
1035 * but could be due to lost FCP transfer ready, confirm or RRQ.
1036 * We always handle this as an exchange abort, ignoring the parameter.
1038 static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp)
1040 struct fc_frame *fp;
1041 struct fc_ba_acc *ap;
1042 struct fc_frame_header *fh;
1047 spin_lock_bh(&ep->ex_lock);
1048 if (ep->esb_stat & ESB_ST_COMPLETE) {
1049 spin_unlock_bh(&ep->ex_lock);
1052 if (!(ep->esb_stat & ESB_ST_REC_QUAL))
1053 fc_exch_hold(ep); /* hold for REC_QUAL */
1054 ep->esb_stat |= ESB_ST_ABNORMAL | ESB_ST_REC_QUAL;
1055 fc_exch_timer_set_locked(ep, ep->r_a_tov);
1057 fp = fc_frame_alloc(ep->lp, sizeof(*ap));
1059 spin_unlock_bh(&ep->ex_lock);
1062 fh = fc_frame_header_get(fp);
1063 ap = fc_frame_payload_get(fp, sizeof(*ap));
1064 memset(ap, 0, sizeof(*ap));
1066 ap->ba_high_seq_cnt = htons(0xffff);
1067 if (sp->ssb_stat & SSB_ST_RESP) {
1068 ap->ba_seq_id = sp->id;
1069 ap->ba_seq_id_val = FC_BA_SEQ_ID_VAL;
1070 ap->ba_high_seq_cnt = fh->fh_seq_cnt;
1071 ap->ba_low_seq_cnt = htons(sp->cnt);
1073 sp = fc_seq_start_next_locked(sp);
1074 spin_unlock_bh(&ep->ex_lock);
1075 fc_seq_send_last(sp, fp, FC_RCTL_BA_ACC, FC_TYPE_BLS);
1076 fc_frame_free(rx_fp);
1080 fc_exch_send_ba_rjt(rx_fp, FC_BA_RJT_UNABLE, FC_BA_RJT_INV_XID);
1082 fc_frame_free(rx_fp);
1086 * Handle receive where the other end is originating the sequence.
1088 static void fc_exch_recv_req(struct fc_lport *lp, struct fc_exch_mgr *mp,
1089 struct fc_frame *fp)
1091 struct fc_frame_header *fh = fc_frame_header_get(fp);
1092 struct fc_seq *sp = NULL;
1093 struct fc_exch *ep = NULL;
1097 enum fc_pf_rjt_reason reject;
1100 reject = fc_seq_lookup_recip(mp, fp);
1101 if (reject == FC_RJT_NONE) {
1102 sp = fr_seq(fp); /* sequence will be held */
1103 ep = fc_seq_exch(sp);
1106 f_ctl = ntoh24(fh->fh_f_ctl);
1107 fc_seq_send_ack(sp, fp);
1110 * Call the receive function.
1112 * The receive function may allocate a new sequence
1113 * over the old one, so we shouldn't change the
1114 * sequence after this.
1116 * The frame will be freed by the receive function.
1117 * If new exch resp handler is valid then call that
1121 ep->resp(sp, fp, ep->arg);
1123 lp->tt.lport_recv(lp, sp, fp);
1124 fc_exch_release(ep); /* release from lookup */
1126 FC_EM_DBG(mp, "exch/seq lookup failed: reject %x\n", reject);
1132 * Handle receive where the other end is originating the sequence in
1133 * response to our exchange.
1135 static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1137 struct fc_frame_header *fh = fc_frame_header_get(fp);
1142 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1146 ep = fc_exch_find(mp, ntohs(fh->fh_ox_id));
1148 atomic_inc(&mp->stats.xid_not_found);
1151 if (ep->esb_stat & ESB_ST_COMPLETE) {
1152 atomic_inc(&mp->stats.xid_not_found);
1155 if (ep->rxid == FC_XID_UNKNOWN)
1156 ep->rxid = ntohs(fh->fh_rx_id);
1157 if (ep->sid != 0 && ep->sid != ntoh24(fh->fh_d_id)) {
1158 atomic_inc(&mp->stats.xid_not_found);
1161 if (ep->did != ntoh24(fh->fh_s_id) &&
1162 ep->did != FC_FID_FLOGI) {
1163 atomic_inc(&mp->stats.xid_not_found);
1167 if (fc_sof_is_init(sof)) {
1168 sp = fc_seq_start_next(&ep->seq);
1169 sp->id = fh->fh_seq_id;
1170 sp->ssb_stat |= SSB_ST_RESP;
1173 if (sp->id != fh->fh_seq_id) {
1174 atomic_inc(&mp->stats.seq_not_found);
1178 f_ctl = ntoh24(fh->fh_f_ctl);
1180 if (f_ctl & FC_FC_SEQ_INIT)
1181 ep->esb_stat |= ESB_ST_SEQ_INIT;
1183 if (fc_sof_needs_ack(sof))
1184 fc_seq_send_ack(sp, fp);
1186 ex_resp_arg = ep->arg;
1188 if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T &&
1189 (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) ==
1190 (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) {
1191 spin_lock_bh(&ep->ex_lock);
1192 rc = fc_exch_done_locked(ep);
1193 WARN_ON(fc_seq_exch(sp) != ep);
1194 spin_unlock_bh(&ep->ex_lock);
1196 fc_exch_mgr_delete_ep(ep);
1200 * Call the receive function.
1201 * The sequence is held (has a refcnt) for us,
1202 * but not for the receive function.
1204 * The receive function may allocate a new sequence
1205 * over the old one, so we shouldn't change the
1206 * sequence after this.
1208 * The frame will be freed by the receive function.
1209 * If new exch resp handler is valid then call that
1213 resp(sp, fp, ex_resp_arg);
1216 fc_exch_release(ep);
1219 fc_exch_release(ep);
1225 * Handle receive for a sequence where other end is responding to our sequence.
1227 static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp)
1231 sp = fc_seq_lookup_orig(mp, fp); /* doesn't hold sequence */
1233 atomic_inc(&mp->stats.xid_not_found);
1234 FC_EM_DBG(mp, "seq lookup failed\n");
1236 atomic_inc(&mp->stats.non_bls_resp);
1237 FC_EM_DBG(mp, "non-BLS response to sequence");
1243 * Handle the response to an ABTS for exchange or sequence.
1244 * This can be BA_ACC or BA_RJT.
1246 static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp)
1248 void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg);
1250 struct fc_frame_header *fh;
1251 struct fc_ba_acc *ap;
1255 int rc = 1, has_rec = 0;
1257 fh = fc_frame_header_get(fp);
1258 FC_EXCH_DBG(ep, "exch: BLS rctl %x - %s\n", fh->fh_r_ctl,
1259 fc_exch_rctl_name(fh->fh_r_ctl));
1261 if (cancel_delayed_work_sync(&ep->timeout_work))
1262 fc_exch_release(ep); /* release from pending timer hold */
1264 spin_lock_bh(&ep->ex_lock);
1265 switch (fh->fh_r_ctl) {
1266 case FC_RCTL_BA_ACC:
1267 ap = fc_frame_payload_get(fp, sizeof(*ap));
1272 * Decide whether to establish a Recovery Qualifier.
1273 * We do this if there is a non-empty SEQ_CNT range and
1274 * SEQ_ID is the same as the one we aborted.
1276 low = ntohs(ap->ba_low_seq_cnt);
1277 high = ntohs(ap->ba_high_seq_cnt);
1278 if ((ep->esb_stat & ESB_ST_REC_QUAL) == 0 &&
1279 (ap->ba_seq_id_val != FC_BA_SEQ_ID_VAL ||
1280 ap->ba_seq_id == ep->seq_id) && low != high) {
1281 ep->esb_stat |= ESB_ST_REC_QUAL;
1282 fc_exch_hold(ep); /* hold for recovery qualifier */
1286 case FC_RCTL_BA_RJT:
1293 ex_resp_arg = ep->arg;
1295 /* do we need to do some other checks here. Can we reuse more of
1296 * fc_exch_recv_seq_resp
1300 * do we want to check END_SEQ as well as LAST_SEQ here?
1302 if (ep->fh_type != FC_TYPE_FCP &&
1303 ntoh24(fh->fh_f_ctl) & FC_FC_LAST_SEQ)
1304 rc = fc_exch_done_locked(ep);
1305 spin_unlock_bh(&ep->ex_lock);
1307 fc_exch_mgr_delete_ep(ep);
1310 resp(sp, fp, ex_resp_arg);
1315 fc_exch_timer_set(ep, ep->r_a_tov);
1320 * Receive BLS sequence.
1321 * This is always a sequence initiated by the remote side.
1322 * We may be either the originator or recipient of the exchange.
1324 static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp)
1326 struct fc_frame_header *fh;
1330 fh = fc_frame_header_get(fp);
1331 f_ctl = ntoh24(fh->fh_f_ctl);
1334 ep = fc_exch_find(mp, (f_ctl & FC_FC_EX_CTX) ?
1335 ntohs(fh->fh_ox_id) : ntohs(fh->fh_rx_id));
1336 if (ep && (f_ctl & FC_FC_SEQ_INIT)) {
1337 spin_lock_bh(&ep->ex_lock);
1338 ep->esb_stat |= ESB_ST_SEQ_INIT;
1339 spin_unlock_bh(&ep->ex_lock);
1341 if (f_ctl & FC_FC_SEQ_CTX) {
1343 * A response to a sequence we initiated.
1344 * This should only be ACKs for class 2 or F.
1346 switch (fh->fh_r_ctl) {
1351 FC_EXCH_DBG(ep, "BLS rctl %x - %s received",
1353 fc_exch_rctl_name(fh->fh_r_ctl));
1358 switch (fh->fh_r_ctl) {
1359 case FC_RCTL_BA_RJT:
1360 case FC_RCTL_BA_ACC:
1362 fc_exch_abts_resp(ep, fp);
1366 case FC_RCTL_BA_ABTS:
1367 fc_exch_recv_abts(ep, fp);
1369 default: /* ignore junk */
1375 fc_exch_release(ep); /* release hold taken by fc_exch_find */
1379 * Accept sequence with LS_ACC.
1380 * If this fails due to allocation or transmit congestion, assume the
1381 * originator will repeat the sequence.
1383 static void fc_seq_ls_acc(struct fc_seq *req_sp)
1386 struct fc_els_ls_acc *acc;
1387 struct fc_frame *fp;
1389 sp = fc_seq_start_next(req_sp);
1390 fp = fc_frame_alloc(fc_seq_exch(sp)->lp, sizeof(*acc));
1392 acc = fc_frame_payload_get(fp, sizeof(*acc));
1393 memset(acc, 0, sizeof(*acc));
1394 acc->la_cmd = ELS_LS_ACC;
1395 fc_seq_send_last(sp, fp, FC_RCTL_ELS_REP, FC_TYPE_ELS);
1400 * Reject sequence with ELS LS_RJT.
1401 * If this fails due to allocation or transmit congestion, assume the
1402 * originator will repeat the sequence.
1404 static void fc_seq_ls_rjt(struct fc_seq *req_sp, enum fc_els_rjt_reason reason,
1405 enum fc_els_rjt_explan explan)
1408 struct fc_els_ls_rjt *rjt;
1409 struct fc_frame *fp;
1411 sp = fc_seq_start_next(req_sp);
1412 fp = fc_frame_alloc(fc_seq_exch(sp)->lp, sizeof(*rjt));
1414 rjt = fc_frame_payload_get(fp, sizeof(*rjt));
1415 memset(rjt, 0, sizeof(*rjt));
1416 rjt->er_cmd = ELS_LS_RJT;
1417 rjt->er_reason = reason;
1418 rjt->er_explan = explan;
1419 fc_seq_send_last(sp, fp, FC_RCTL_ELS_REP, FC_TYPE_ELS);
1423 static void fc_exch_reset(struct fc_exch *ep)
1426 void (*resp)(struct fc_seq *, struct fc_frame *, void *);
1430 spin_lock_bh(&ep->ex_lock);
1431 ep->state |= FC_EX_RST_CLEANUP;
1433 * we really want to call del_timer_sync, but cannot due
1434 * to the lport calling with the lport lock held (some resp
1435 * functions can also grab the lport lock which could cause
1438 if (cancel_delayed_work(&ep->timeout_work))
1439 atomic_dec(&ep->ex_refcnt); /* drop hold for timer */
1442 if (ep->esb_stat & ESB_ST_REC_QUAL)
1443 atomic_dec(&ep->ex_refcnt); /* drop hold for rec_qual */
1444 ep->esb_stat &= ~ESB_ST_REC_QUAL;
1447 rc = fc_exch_done_locked(ep);
1448 spin_unlock_bh(&ep->ex_lock);
1450 fc_exch_mgr_delete_ep(ep);
1453 resp(sp, ERR_PTR(-FC_EX_CLOSED), arg);
1457 * Reset an exchange manager, releasing all sequences and exchanges.
1458 * If sid is non-zero, reset only exchanges we source from that FID.
1459 * If did is non-zero, reset only exchanges destined to that FID.
1461 void fc_exch_mgr_reset(struct fc_lport *lp, u32 sid, u32 did)
1464 struct fc_exch *next;
1465 struct fc_exch_mgr *mp = lp->emp;
1467 spin_lock_bh(&mp->em_lock);
1469 list_for_each_entry_safe(ep, next, &mp->ex_list, ex_list) {
1470 if ((sid == 0 || sid == ep->sid) &&
1471 (did == 0 || did == ep->did)) {
1473 spin_unlock_bh(&mp->em_lock);
1477 fc_exch_release(ep);
1478 spin_lock_bh(&mp->em_lock);
1481 * must restart loop incase while lock was down
1482 * multiple eps were released.
1487 spin_unlock_bh(&mp->em_lock);
1489 EXPORT_SYMBOL(fc_exch_mgr_reset);
1492 * Handle incoming ELS REC - Read Exchange Concise.
1493 * Note that the requesting port may be different than the S_ID in the request.
1495 static void fc_exch_els_rec(struct fc_seq *sp, struct fc_frame *rfp)
1497 struct fc_frame *fp;
1499 struct fc_exch_mgr *em;
1500 struct fc_els_rec *rp;
1501 struct fc_els_rec_acc *acc;
1502 enum fc_els_rjt_reason reason = ELS_RJT_LOGIC;
1503 enum fc_els_rjt_explan explan;
1508 rp = fc_frame_payload_get(rfp, sizeof(*rp));
1509 explan = ELS_EXPL_INV_LEN;
1512 sid = ntoh24(rp->rec_s_id);
1513 rxid = ntohs(rp->rec_rx_id);
1514 oxid = ntohs(rp->rec_ox_id);
1517 * Currently it's hard to find the local S_ID from the exchange
1518 * manager. This will eventually be fixed, but for now it's easier
1519 * to lookup the subject exchange twice, once as if we were
1520 * the initiator, and then again if we weren't.
1522 em = fc_seq_exch(sp)->em;
1523 ep = fc_exch_find(em, oxid);
1524 explan = ELS_EXPL_OXID_RXID;
1525 if (ep && ep->oid == sid) {
1526 if (ep->rxid != FC_XID_UNKNOWN &&
1527 rxid != FC_XID_UNKNOWN &&
1532 fc_exch_release(ep);
1534 if (rxid != FC_XID_UNKNOWN)
1535 ep = fc_exch_find(em, rxid);
1540 fp = fc_frame_alloc(fc_seq_exch(sp)->lp, sizeof(*acc));
1545 sp = fc_seq_start_next(sp);
1546 acc = fc_frame_payload_get(fp, sizeof(*acc));
1547 memset(acc, 0, sizeof(*acc));
1548 acc->reca_cmd = ELS_LS_ACC;
1549 acc->reca_ox_id = rp->rec_ox_id;
1550 memcpy(acc->reca_ofid, rp->rec_s_id, 3);
1551 acc->reca_rx_id = htons(ep->rxid);
1552 if (ep->sid == ep->oid)
1553 hton24(acc->reca_rfid, ep->did);
1555 hton24(acc->reca_rfid, ep->sid);
1556 acc->reca_fc4value = htonl(ep->seq.rec_data);
1557 acc->reca_e_stat = htonl(ep->esb_stat & (ESB_ST_RESP |
1560 sp = fc_seq_start_next(sp);
1561 fc_seq_send_last(sp, fp, FC_RCTL_ELS_REP, FC_TYPE_ELS);
1563 fc_exch_release(ep);
1568 fc_exch_release(ep);
1570 fc_seq_ls_rjt(sp, reason, explan);
1575 * Handle response from RRQ.
1576 * Not much to do here, really.
1577 * Should report errors.
1579 * TODO: fix error handler.
1581 static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg)
1583 struct fc_exch *aborted_ep = arg;
1587 int err = PTR_ERR(fp);
1589 if (err == -FC_EX_CLOSED || err == -FC_EX_TIMEOUT)
1591 FC_EXCH_DBG(aborted_ep, "Cannot process RRQ, "
1592 "frame error %d\n", err);
1596 op = fc_frame_payload_op(fp);
1601 FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ");
1606 FC_EXCH_DBG(aborted_ep, "unexpected response op %x "
1612 fc_exch_done(&aborted_ep->seq);
1613 /* drop hold for rec qual */
1614 fc_exch_release(aborted_ep);
1618 * Send ELS RRQ - Reinstate Recovery Qualifier.
1619 * This tells the remote port to stop blocking the use of
1620 * the exchange and the seq_cnt range.
1622 static void fc_exch_rrq(struct fc_exch *ep)
1624 struct fc_lport *lp;
1625 struct fc_els_rrq *rrq;
1626 struct fc_frame *fp;
1631 fp = fc_frame_alloc(lp, sizeof(*rrq));
1635 rrq = fc_frame_payload_get(fp, sizeof(*rrq));
1636 memset(rrq, 0, sizeof(*rrq));
1637 rrq->rrq_cmd = ELS_RRQ;
1638 hton24(rrq->rrq_s_id, ep->sid);
1639 rrq->rrq_ox_id = htons(ep->oxid);
1640 rrq->rrq_rx_id = htons(ep->rxid);
1643 if (ep->esb_stat & ESB_ST_RESP)
1646 fc_fill_fc_hdr(fp, FC_RCTL_ELS_REQ, did,
1647 fc_host_port_id(lp->host), FC_TYPE_ELS,
1648 FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, 0);
1650 if (fc_exch_seq_send(lp, fp, fc_exch_rrq_resp, NULL, ep, lp->e_d_tov))
1654 spin_lock_bh(&ep->ex_lock);
1655 if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) {
1656 spin_unlock_bh(&ep->ex_lock);
1657 /* drop hold for rec qual */
1658 fc_exch_release(ep);
1661 ep->esb_stat |= ESB_ST_REC_QUAL;
1662 fc_exch_timer_set_locked(ep, ep->r_a_tov);
1663 spin_unlock_bh(&ep->ex_lock);
1668 * Handle incoming ELS RRQ - Reset Recovery Qualifier.
1670 static void fc_exch_els_rrq(struct fc_seq *sp, struct fc_frame *fp)
1672 struct fc_exch *ep; /* request or subject exchange */
1673 struct fc_els_rrq *rp;
1676 enum fc_els_rjt_explan explan;
1678 rp = fc_frame_payload_get(fp, sizeof(*rp));
1679 explan = ELS_EXPL_INV_LEN;
1684 * lookup subject exchange.
1686 ep = fc_seq_exch(sp);
1687 sid = ntoh24(rp->rrq_s_id); /* subject source */
1688 xid = ep->did == sid ? ntohs(rp->rrq_ox_id) : ntohs(rp->rrq_rx_id);
1689 ep = fc_exch_find(ep->em, xid);
1691 explan = ELS_EXPL_OXID_RXID;
1694 spin_lock_bh(&ep->ex_lock);
1695 if (ep->oxid != ntohs(rp->rrq_ox_id))
1697 if (ep->rxid != ntohs(rp->rrq_rx_id) &&
1698 ep->rxid != FC_XID_UNKNOWN)
1700 explan = ELS_EXPL_SID;
1705 * Clear Recovery Qualifier state, and cancel timer if complete.
1707 if (ep->esb_stat & ESB_ST_REC_QUAL) {
1708 ep->esb_stat &= ~ESB_ST_REC_QUAL;
1709 atomic_dec(&ep->ex_refcnt); /* drop hold for rec qual */
1711 if (ep->esb_stat & ESB_ST_COMPLETE) {
1712 if (cancel_delayed_work(&ep->timeout_work))
1713 atomic_dec(&ep->ex_refcnt); /* drop timer hold */
1716 spin_unlock_bh(&ep->ex_lock);
1726 spin_unlock_bh(&ep->ex_lock);
1727 fc_exch_release(ep); /* drop hold from fc_exch_find */
1729 fc_seq_ls_rjt(sp, ELS_RJT_LOGIC, explan);
1733 struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lp,
1734 enum fc_class class,
1735 u16 min_xid, u16 max_xid)
1737 struct fc_exch_mgr *mp;
1740 if (max_xid <= min_xid || min_xid == 0 || max_xid == FC_XID_UNKNOWN) {
1741 FC_LPORT_DBG(lp, "Invalid min_xid 0x:%x and max_xid 0x:%x\n",
1747 * Memory need for EM
1749 #define xid_ok(i, m1, m2) (((i) >= (m1)) && ((i) <= (m2)))
1750 len = (max_xid - min_xid + 1) * (sizeof(struct fc_exch *));
1751 len += sizeof(struct fc_exch_mgr);
1753 mp = kzalloc(len, GFP_ATOMIC);
1758 mp->total_exches = 0;
1759 mp->exches = (struct fc_exch **)(mp + 1);
1761 /* adjust em exch xid range for offload */
1762 mp->min_xid = min_xid;
1763 mp->max_xid = max_xid;
1764 mp->last_xid = min_xid - 1;
1767 if (lp->lro_enabled && xid_ok(lp->lro_xid, min_xid, max_xid)) {
1768 mp->max_read = lp->lro_xid;
1769 mp->last_read = min_xid - 1;
1770 mp->last_xid = mp->max_read;
1772 /* disable lro if no xid control over read */
1773 lp->lro_enabled = 0;
1776 INIT_LIST_HEAD(&mp->ex_list);
1777 spin_lock_init(&mp->em_lock);
1779 mp->ep_pool = mempool_create_slab_pool(2, fc_em_cachep);
1789 EXPORT_SYMBOL(fc_exch_mgr_alloc);
1791 void fc_exch_mgr_free(struct fc_exch_mgr *mp)
1795 * The total exch count must be zero
1796 * before freeing exchange manager.
1798 WARN_ON(mp->total_exches != 0);
1799 mempool_destroy(mp->ep_pool);
1802 EXPORT_SYMBOL(fc_exch_mgr_free);
1804 struct fc_exch *fc_exch_get(struct fc_lport *lp, struct fc_frame *fp)
1806 if (!lp || !lp->emp)
1809 return fc_exch_alloc(lp->emp, fp, 0);
1811 EXPORT_SYMBOL(fc_exch_get);
1813 struct fc_seq *fc_exch_seq_send(struct fc_lport *lp,
1814 struct fc_frame *fp,
1815 void (*resp)(struct fc_seq *,
1816 struct fc_frame *fp,
1818 void (*destructor)(struct fc_seq *, void *),
1819 void *arg, u32 timer_msec)
1822 struct fc_seq *sp = NULL;
1823 struct fc_frame_header *fh;
1826 ep = lp->tt.exch_get(lp, fp);
1831 ep->esb_stat |= ESB_ST_SEQ_INIT;
1832 fh = fc_frame_header_get(fp);
1833 fc_exch_set_addr(ep, ntoh24(fh->fh_s_id), ntoh24(fh->fh_d_id));
1835 ep->destructor = destructor;
1837 ep->r_a_tov = FC_DEF_R_A_TOV;
1841 ep->fh_type = fh->fh_type; /* save for possbile timeout handling */
1842 ep->f_ctl = ntoh24(fh->fh_f_ctl);
1843 fc_exch_setup_hdr(ep, fp, ep->f_ctl);
1846 fc_fcp_ddp_setup(fr_fsp(fp), ep->xid);
1848 if (unlikely(lp->tt.frame_send(lp, fp)))
1852 fc_exch_timer_set_locked(ep, timer_msec);
1853 ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not first seq */
1855 if (ep->f_ctl & FC_FC_SEQ_INIT)
1856 ep->esb_stat &= ~ESB_ST_SEQ_INIT;
1857 spin_unlock_bh(&ep->ex_lock);
1860 rc = fc_exch_done_locked(ep);
1861 spin_unlock_bh(&ep->ex_lock);
1863 fc_exch_mgr_delete_ep(ep);
1866 EXPORT_SYMBOL(fc_exch_seq_send);
1871 void fc_exch_recv(struct fc_lport *lp, struct fc_exch_mgr *mp,
1872 struct fc_frame *fp)
1874 struct fc_frame_header *fh = fc_frame_header_get(fp);
1878 if (!lp || !mp || (lp->state == LPORT_ST_NONE)) {
1879 FC_LPORT_DBG(lp, "Receiving frames for an lport that "
1880 "has not been initialized correctly\n");
1886 * If frame is marked invalid, just drop it.
1888 f_ctl = ntoh24(fh->fh_f_ctl);
1889 switch (fr_eof(fp)) {
1891 if (f_ctl & FC_FC_END_SEQ)
1892 skb_trim(fp_skb(fp), fr_len(fp) - FC_FC_FILL(f_ctl));
1895 if (fh->fh_type == FC_TYPE_BLS)
1896 fc_exch_recv_bls(mp, fp);
1897 else if ((f_ctl & (FC_FC_EX_CTX | FC_FC_SEQ_CTX)) ==
1899 fc_exch_recv_seq_resp(mp, fp);
1900 else if (f_ctl & FC_FC_SEQ_CTX)
1901 fc_exch_recv_resp(mp, fp);
1903 fc_exch_recv_req(lp, mp, fp);
1906 FC_EM_DBG(mp, "dropping invalid frame (eof %x)", fr_eof(fp));
1911 EXPORT_SYMBOL(fc_exch_recv);
1913 int fc_exch_init(struct fc_lport *lp)
1915 if (!lp->tt.exch_get) {
1917 * exch_put() should be NULL if
1918 * exch_get() is NULL
1920 WARN_ON(lp->tt.exch_put);
1921 lp->tt.exch_get = fc_exch_get;
1924 if (!lp->tt.seq_start_next)
1925 lp->tt.seq_start_next = fc_seq_start_next;
1927 if (!lp->tt.exch_seq_send)
1928 lp->tt.exch_seq_send = fc_exch_seq_send;
1930 if (!lp->tt.seq_send)
1931 lp->tt.seq_send = fc_seq_send;
1933 if (!lp->tt.seq_els_rsp_send)
1934 lp->tt.seq_els_rsp_send = fc_seq_els_rsp_send;
1936 if (!lp->tt.exch_done)
1937 lp->tt.exch_done = fc_exch_done;
1939 if (!lp->tt.exch_mgr_reset)
1940 lp->tt.exch_mgr_reset = fc_exch_mgr_reset;
1942 if (!lp->tt.seq_exch_abort)
1943 lp->tt.seq_exch_abort = fc_seq_exch_abort;
1947 EXPORT_SYMBOL(fc_exch_init);
1949 int fc_setup_exch_mgr(void)
1951 fc_em_cachep = kmem_cache_create("libfc_em", sizeof(struct fc_exch),
1952 0, SLAB_HWCACHE_ALIGN, NULL);
1958 void fc_destroy_exch_mgr(void)
1960 kmem_cache_destroy(fc_em_cachep);