1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright(c) 2007 Intel Corporation. All rights reserved. |
4 | * Copyright(c) 2008 Red Hat, Inc. All rights reserved. |
5 | * Copyright(c) 2008 Mike Christie |
6 | * |
7 | * Maintained at www.Open-FCoE.org |
8 | */ |
9 | |
10 | /* |
11 | * Fibre Channel exchange and sequence handling. |
12 | */ |
13 | |
14 | #include <linux/timer.h> |
15 | #include <linux/slab.h> |
16 | #include <linux/err.h> |
17 | #include <linux/export.h> |
18 | #include <linux/log2.h> |
19 | |
20 | #include <scsi/fc/fc_fc2.h> |
21 | |
22 | #include <scsi/libfc.h> |
23 | |
24 | #include "fc_libfc.h" |
25 | |
26 | u16 fc_cpu_mask; /* cpu mask for possible cpus */ |
27 | EXPORT_SYMBOL(fc_cpu_mask); |
28 | static u16 fc_cpu_order; /* 2's power to represent total possible cpus */ |
29 | static struct kmem_cache *fc_em_cachep; /* cache for exchanges */ |
30 | static struct workqueue_struct *fc_exch_workqueue; |
31 | |
32 | /* |
33 | * Structure and function definitions for managing Fibre Channel Exchanges |
34 | * and Sequences. |
35 | * |
36 | * The three primary structures used here are fc_exch_mgr, fc_exch, and fc_seq. |
37 | * |
38 | * fc_exch_mgr holds the exchange state for an N port |
39 | * |
40 | * fc_exch holds state for one exchange and links to its active sequence. |
41 | * |
42 | * fc_seq holds the state for an individual sequence. |
43 | */ |
44 | |
45 | /** |
46 | * struct fc_exch_pool - Per cpu exchange pool |
47 | * @next_index: Next possible free exchange index |
48 | * @total_exches: Total allocated exchanges |
49 | * @lock: Exch pool lock |
50 | * @ex_list: List of exchanges |
51 | * @left: Cache of free slot in exch array |
52 | * @right: Cache of free slot in exch array |
53 | * |
54 | * This structure manages per cpu exchanges in array of exchange pointers. |
55 | * This array is allocated followed by struct fc_exch_pool memory for |
56 | * assigned range of exchanges to per cpu pool. |
57 | */ |
58 | struct fc_exch_pool { |
59 | spinlock_t lock; |
60 | struct list_head ex_list; |
61 | u16 next_index; |
62 | u16 total_exches; |
63 | |
64 | u16 left; |
65 | u16 right; |
66 | } ____cacheline_aligned_in_smp; |
67 | |
68 | /** |
69 | * struct fc_exch_mgr - The Exchange Manager (EM). |
70 | * @class: Default class for new sequences |
71 | * @kref: Reference counter |
72 | * @min_xid: Minimum exchange ID |
73 | * @max_xid: Maximum exchange ID |
74 | * @ep_pool: Reserved exchange pointers |
75 | * @pool_max_index: Max exch array index in exch pool |
76 | * @pool: Per cpu exch pool |
77 | * @lport: Local exchange port |
78 | * @stats: Statistics structure |
79 | * |
80 | * This structure is the center for creating exchanges and sequences. |
81 | * It manages the allocation of exchange IDs. |
82 | */ |
83 | struct fc_exch_mgr { |
84 | struct fc_exch_pool __percpu *pool; |
85 | mempool_t *ep_pool; |
86 | struct fc_lport *lport; |
87 | enum fc_class class; |
88 | struct kref kref; |
89 | u16 min_xid; |
90 | u16 max_xid; |
91 | u16 pool_max_index; |
92 | |
93 | struct { |
94 | atomic_t no_free_exch; |
95 | atomic_t no_free_exch_xid; |
96 | atomic_t xid_not_found; |
97 | atomic_t xid_busy; |
98 | atomic_t seq_not_found; |
99 | atomic_t non_bls_resp; |
100 | } stats; |
101 | }; |
102 | |
103 | /** |
104 | * struct fc_exch_mgr_anchor - primary structure for list of EMs |
105 | * @ema_list: Exchange Manager Anchor list |
106 | * @mp: Exchange Manager associated with this anchor |
107 | * @match: Routine to determine if this anchor's EM should be used |
108 | * |
109 | * When walking the list of anchors the match routine will be called |
110 | * for each anchor to determine if that EM should be used. The last |
111 | * anchor in the list will always match to handle any exchanges not |
112 | * handled by other EMs. The non-default EMs would be added to the |
113 | * anchor list by HW that provides offloads. |
114 | */ |
115 | struct fc_exch_mgr_anchor { |
116 | struct list_head ema_list; |
117 | struct fc_exch_mgr *mp; |
118 | bool (*match)(struct fc_frame *); |
119 | }; |
120 | |
121 | static void fc_exch_rrq(struct fc_exch *); |
122 | static void fc_seq_ls_acc(struct fc_frame *); |
123 | static void fc_seq_ls_rjt(struct fc_frame *, enum fc_els_rjt_reason, |
124 | enum fc_els_rjt_explan); |
125 | static void fc_exch_els_rec(struct fc_frame *); |
126 | static void fc_exch_els_rrq(struct fc_frame *); |
127 | |
128 | /* |
129 | * Internal implementation notes. |
130 | * |
131 | * The exchange manager is one by default in libfc but LLD may choose |
132 | * to have one per CPU. The sequence manager is one per exchange manager |
133 | * and currently never separated. |
134 | * |
135 | * Section 9.8 in FC-FS-2 specifies: "The SEQ_ID is a one-byte field |
136 | * assigned by the Sequence Initiator that shall be unique for a specific |
137 | * D_ID and S_ID pair while the Sequence is open." Note that it isn't |
138 | * qualified by exchange ID, which one might think it would be. |
139 | * In practice this limits the number of open sequences and exchanges to 256 |
140 | * per session. For most targets we could treat this limit as per exchange. |
141 | * |
142 | * The exchange and its sequence are freed when the last sequence is received. |
143 | * It's possible for the remote port to leave an exchange open without |
144 | * sending any sequences. |
145 | * |
146 | * Notes on reference counts: |
147 | * |
148 | * Exchanges are reference counted and exchange gets freed when the reference |
149 | * count becomes zero. |
150 | * |
151 | * Timeouts: |
152 | * Sequences are timed out for E_D_TOV and R_A_TOV. |
153 | * |
154 | * Sequence event handling: |
155 | * |
156 | * The following events may occur on initiator sequences: |
157 | * |
158 | * Send. |
159 | * For now, the whole thing is sent. |
160 | * Receive ACK |
161 | * This applies only to class F. |
162 | * The sequence is marked complete. |
163 | * ULP completion. |
164 | * The upper layer calls fc_exch_done() when done |
165 | * with exchange and sequence tuple. |
166 | * RX-inferred completion. |
167 | * When we receive the next sequence on the same exchange, we can |
168 | * retire the previous sequence ID. (XXX not implemented). |
169 | * Timeout. |
170 | * R_A_TOV frees the sequence ID. If we're waiting for ACK, |
171 | * E_D_TOV causes abort and calls upper layer response handler |
172 | * with FC_EX_TIMEOUT error. |
173 | * Receive RJT |
174 | * XXX defer. |
175 | * Send ABTS |
176 | * On timeout. |
177 | * |
178 | * The following events may occur on recipient sequences: |
179 | * |
180 | * Receive |
181 | * Allocate sequence for first frame received. |
182 | * Hold during receive handler. |
183 | * Release when final frame received. |
184 | * Keep status of last N of these for the ELS RES command. XXX TBD. |
185 | * Receive ABTS |
186 | * Deallocate sequence |
187 | * Send RJT |
188 | * Deallocate |
189 | * |
190 | * For now, we neglect conditions where only part of a sequence was |
191 | * received or transmitted, or where out-of-order receipt is detected. |
192 | */ |
193 | |
194 | /* |
195 | * Locking notes: |
196 | * |
197 | * The EM code run in a per-CPU worker thread. |
198 | * |
199 | * To protect against concurrency between a worker thread code and timers, |
200 | * sequence allocation and deallocation must be locked. |
201 | * - exchange refcnt can be done atomicly without locks. |
202 | * - sequence allocation must be locked by exch lock. |
203 | * - If the EM pool lock and ex_lock must be taken at the same time, then the |
204 | * EM pool lock must be taken before the ex_lock. |
205 | */ |
206 | |
207 | /* |
208 | * opcode names for debugging. |
209 | */ |
210 | static char *fc_exch_rctl_names[] = FC_RCTL_NAMES_INIT; |
211 | |
212 | /** |
213 | * fc_exch_name_lookup() - Lookup name by opcode |
214 | * @op: Opcode to be looked up |
215 | * @table: Opcode/name table |
216 | * @max_index: Index not to be exceeded |
217 | * |
218 | * This routine is used to determine a human-readable string identifying |
219 | * a R_CTL opcode. |
220 | */ |
221 | static inline const char *fc_exch_name_lookup(unsigned int op, char **table, |
222 | unsigned int max_index) |
223 | { |
224 | const char *name = NULL; |
225 | |
226 | if (op < max_index) |
227 | name = table[op]; |
228 | if (!name) |
229 | name = "unknown" ; |
230 | return name; |
231 | } |
232 | |
233 | /** |
234 | * fc_exch_rctl_name() - Wrapper routine for fc_exch_name_lookup() |
235 | * @op: The opcode to be looked up |
236 | */ |
237 | static const char *fc_exch_rctl_name(unsigned int op) |
238 | { |
239 | return fc_exch_name_lookup(op, table: fc_exch_rctl_names, |
240 | ARRAY_SIZE(fc_exch_rctl_names)); |
241 | } |
242 | |
243 | /** |
244 | * fc_exch_hold() - Increment an exchange's reference count |
245 | * @ep: Echange to be held |
246 | */ |
247 | static inline void fc_exch_hold(struct fc_exch *ep) |
248 | { |
249 | atomic_inc(v: &ep->ex_refcnt); |
250 | } |
251 | |
252 | /** |
253 | * fc_exch_setup_hdr() - Initialize a FC header by initializing some fields |
254 | * and determine SOF and EOF. |
255 | * @ep: The exchange to that will use the header |
256 | * @fp: The frame whose header is to be modified |
257 | * @f_ctl: F_CTL bits that will be used for the frame header |
258 | * |
259 | * The fields initialized by this routine are: fh_ox_id, fh_rx_id, |
260 | * fh_seq_id, fh_seq_cnt and the SOF and EOF. |
261 | */ |
262 | static void fc_exch_setup_hdr(struct fc_exch *ep, struct fc_frame *fp, |
263 | u32 f_ctl) |
264 | { |
265 | struct fc_frame_header *fh = fc_frame_header_get(fp); |
266 | u16 fill; |
267 | |
268 | fr_sof(fp) = ep->class; |
269 | if (ep->seq.cnt) |
270 | fr_sof(fp) = fc_sof_normal(class: ep->class); |
271 | |
272 | if (f_ctl & FC_FC_END_SEQ) { |
273 | fr_eof(fp) = FC_EOF_T; |
274 | if (fc_sof_needs_ack(sof: (enum fc_sof)ep->class)) |
275 | fr_eof(fp) = FC_EOF_N; |
276 | /* |
277 | * From F_CTL. |
278 | * The number of fill bytes to make the length a 4-byte |
279 | * multiple is the low order 2-bits of the f_ctl. |
280 | * The fill itself will have been cleared by the frame |
281 | * allocation. |
282 | * After this, the length will be even, as expected by |
283 | * the transport. |
284 | */ |
285 | fill = fr_len(fp) & 3; |
286 | if (fill) { |
287 | fill = 4 - fill; |
288 | /* TODO, this may be a problem with fragmented skb */ |
289 | skb_put(fp_skb(fp), len: fill); |
290 | hton24(p: fh->fh_f_ctl, v: f_ctl | fill); |
291 | } |
292 | } else { |
293 | WARN_ON(fr_len(fp) % 4 != 0); /* no pad to non last frame */ |
294 | fr_eof(fp) = FC_EOF_N; |
295 | } |
296 | |
297 | /* Initialize remaining fh fields from fc_fill_fc_hdr */ |
298 | fh->fh_ox_id = htons(ep->oxid); |
299 | fh->fh_rx_id = htons(ep->rxid); |
300 | fh->fh_seq_id = ep->seq.id; |
301 | fh->fh_seq_cnt = htons(ep->seq.cnt); |
302 | } |
303 | |
304 | /** |
305 | * fc_exch_release() - Decrement an exchange's reference count |
306 | * @ep: Exchange to be released |
307 | * |
308 | * If the reference count reaches zero and the exchange is complete, |
309 | * it is freed. |
310 | */ |
311 | static void fc_exch_release(struct fc_exch *ep) |
312 | { |
313 | struct fc_exch_mgr *mp; |
314 | |
315 | if (atomic_dec_and_test(v: &ep->ex_refcnt)) { |
316 | mp = ep->em; |
317 | if (ep->destructor) |
318 | ep->destructor(&ep->seq, ep->arg); |
319 | WARN_ON(!(ep->esb_stat & ESB_ST_COMPLETE)); |
320 | mempool_free(element: ep, pool: mp->ep_pool); |
321 | } |
322 | } |
323 | |
324 | /** |
325 | * fc_exch_timer_cancel() - cancel exch timer |
326 | * @ep: The exchange whose timer to be canceled |
327 | */ |
328 | static inline void fc_exch_timer_cancel(struct fc_exch *ep) |
329 | { |
330 | if (cancel_delayed_work(dwork: &ep->timeout_work)) { |
331 | FC_EXCH_DBG(ep, "Exchange timer canceled\n" ); |
332 | atomic_dec(v: &ep->ex_refcnt); /* drop hold for timer */ |
333 | } |
334 | } |
335 | |
336 | /** |
337 | * fc_exch_timer_set_locked() - Start a timer for an exchange w/ the |
338 | * the exchange lock held |
339 | * @ep: The exchange whose timer will start |
340 | * @timer_msec: The timeout period |
341 | * |
342 | * Used for upper level protocols to time out the exchange. |
343 | * The timer is cancelled when it fires or when the exchange completes. |
344 | */ |
345 | static inline void fc_exch_timer_set_locked(struct fc_exch *ep, |
346 | unsigned int timer_msec) |
347 | { |
348 | if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) |
349 | return; |
350 | |
351 | FC_EXCH_DBG(ep, "Exchange timer armed : %d msecs\n" , timer_msec); |
352 | |
353 | fc_exch_hold(ep); /* hold for timer */ |
354 | if (!queue_delayed_work(wq: fc_exch_workqueue, dwork: &ep->timeout_work, |
355 | delay: msecs_to_jiffies(m: timer_msec))) { |
356 | FC_EXCH_DBG(ep, "Exchange already queued\n" ); |
357 | fc_exch_release(ep); |
358 | } |
359 | } |
360 | |
361 | /** |
362 | * fc_exch_timer_set() - Lock the exchange and set the timer |
363 | * @ep: The exchange whose timer will start |
364 | * @timer_msec: The timeout period |
365 | */ |
366 | static void fc_exch_timer_set(struct fc_exch *ep, unsigned int timer_msec) |
367 | { |
368 | spin_lock_bh(lock: &ep->ex_lock); |
369 | fc_exch_timer_set_locked(ep, timer_msec); |
370 | spin_unlock_bh(lock: &ep->ex_lock); |
371 | } |
372 | |
373 | /** |
374 | * fc_exch_done_locked() - Complete an exchange with the exchange lock held |
375 | * @ep: The exchange that is complete |
376 | * |
377 | * Note: May sleep if invoked from outside a response handler. |
378 | */ |
379 | static int fc_exch_done_locked(struct fc_exch *ep) |
380 | { |
381 | int rc = 1; |
382 | |
383 | /* |
384 | * We must check for completion in case there are two threads |
385 | * tyring to complete this. But the rrq code will reuse the |
386 | * ep, and in that case we only clear the resp and set it as |
387 | * complete, so it can be reused by the timer to send the rrq. |
388 | */ |
389 | if (ep->state & FC_EX_DONE) |
390 | return rc; |
391 | ep->esb_stat |= ESB_ST_COMPLETE; |
392 | |
393 | if (!(ep->esb_stat & ESB_ST_REC_QUAL)) { |
394 | ep->state |= FC_EX_DONE; |
395 | fc_exch_timer_cancel(ep); |
396 | rc = 0; |
397 | } |
398 | return rc; |
399 | } |
400 | |
401 | static struct fc_exch fc_quarantine_exch; |
402 | |
403 | /** |
404 | * fc_exch_ptr_get() - Return an exchange from an exchange pool |
405 | * @pool: Exchange Pool to get an exchange from |
406 | * @index: Index of the exchange within the pool |
407 | * |
408 | * Use the index to get an exchange from within an exchange pool. exches |
409 | * will point to an array of exchange pointers. The index will select |
410 | * the exchange within the array. |
411 | */ |
412 | static inline struct fc_exch *fc_exch_ptr_get(struct fc_exch_pool *pool, |
413 | u16 index) |
414 | { |
415 | struct fc_exch **exches = (struct fc_exch **)(pool + 1); |
416 | return exches[index]; |
417 | } |
418 | |
419 | /** |
420 | * fc_exch_ptr_set() - Assign an exchange to a slot in an exchange pool |
421 | * @pool: The pool to assign the exchange to |
422 | * @index: The index in the pool where the exchange will be assigned |
423 | * @ep: The exchange to assign to the pool |
424 | */ |
425 | static inline void fc_exch_ptr_set(struct fc_exch_pool *pool, u16 index, |
426 | struct fc_exch *ep) |
427 | { |
428 | ((struct fc_exch **)(pool + 1))[index] = ep; |
429 | } |
430 | |
431 | /** |
432 | * fc_exch_delete() - Delete an exchange |
433 | * @ep: The exchange to be deleted |
434 | */ |
435 | static void fc_exch_delete(struct fc_exch *ep) |
436 | { |
437 | struct fc_exch_pool *pool; |
438 | u16 index; |
439 | |
440 | pool = ep->pool; |
441 | spin_lock_bh(lock: &pool->lock); |
442 | WARN_ON(pool->total_exches <= 0); |
443 | pool->total_exches--; |
444 | |
445 | /* update cache of free slot */ |
446 | index = (ep->xid - ep->em->min_xid) >> fc_cpu_order; |
447 | if (!(ep->state & FC_EX_QUARANTINE)) { |
448 | if (pool->left == FC_XID_UNKNOWN) |
449 | pool->left = index; |
450 | else if (pool->right == FC_XID_UNKNOWN) |
451 | pool->right = index; |
452 | else |
453 | pool->next_index = index; |
454 | fc_exch_ptr_set(pool, index, NULL); |
455 | } else { |
456 | fc_exch_ptr_set(pool, index, ep: &fc_quarantine_exch); |
457 | } |
458 | list_del(entry: &ep->ex_list); |
459 | spin_unlock_bh(lock: &pool->lock); |
460 | fc_exch_release(ep); /* drop hold for exch in mp */ |
461 | } |
462 | |
463 | static int fc_seq_send_locked(struct fc_lport *lport, struct fc_seq *sp, |
464 | struct fc_frame *fp) |
465 | { |
466 | struct fc_exch *ep; |
467 | struct fc_frame_header *fh = fc_frame_header_get(fp); |
468 | int error = -ENXIO; |
469 | u32 f_ctl; |
470 | u8 fh_type = fh->fh_type; |
471 | |
472 | ep = fc_seq_exch(sp); |
473 | |
474 | if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL)) { |
475 | fc_frame_free(fp); |
476 | goto out; |
477 | } |
478 | |
479 | WARN_ON(!(ep->esb_stat & ESB_ST_SEQ_INIT)); |
480 | |
481 | f_ctl = ntoh24(p: fh->fh_f_ctl); |
482 | fc_exch_setup_hdr(ep, fp, f_ctl); |
483 | fr_encaps(fp) = ep->encaps; |
484 | |
485 | /* |
486 | * update sequence count if this frame is carrying |
487 | * multiple FC frames when sequence offload is enabled |
488 | * by LLD. |
489 | */ |
490 | if (fr_max_payload(fp)) |
491 | sp->cnt += DIV_ROUND_UP((fr_len(fp) - sizeof(*fh)), |
492 | fr_max_payload(fp)); |
493 | else |
494 | sp->cnt++; |
495 | |
496 | /* |
497 | * Send the frame. |
498 | */ |
499 | error = lport->tt.frame_send(lport, fp); |
500 | |
501 | if (fh_type == FC_TYPE_BLS) |
502 | goto out; |
503 | |
504 | /* |
505 | * Update the exchange and sequence flags, |
506 | * assuming all frames for the sequence have been sent. |
507 | * We can only be called to send once for each sequence. |
508 | */ |
509 | ep->f_ctl = f_ctl & ~FC_FC_FIRST_SEQ; /* not first seq */ |
510 | if (f_ctl & FC_FC_SEQ_INIT) |
511 | ep->esb_stat &= ~ESB_ST_SEQ_INIT; |
512 | out: |
513 | return error; |
514 | } |
515 | |
516 | /** |
517 | * fc_seq_send() - Send a frame using existing sequence/exchange pair |
518 | * @lport: The local port that the exchange will be sent on |
519 | * @sp: The sequence to be sent |
520 | * @fp: The frame to be sent on the exchange |
521 | * |
522 | * Note: The frame will be freed either by a direct call to fc_frame_free(fp) |
523 | * or indirectly by calling libfc_function_template.frame_send(). |
524 | */ |
525 | int fc_seq_send(struct fc_lport *lport, struct fc_seq *sp, struct fc_frame *fp) |
526 | { |
527 | struct fc_exch *ep; |
528 | int error; |
529 | ep = fc_seq_exch(sp); |
530 | spin_lock_bh(lock: &ep->ex_lock); |
531 | error = fc_seq_send_locked(lport, sp, fp); |
532 | spin_unlock_bh(lock: &ep->ex_lock); |
533 | return error; |
534 | } |
535 | EXPORT_SYMBOL(fc_seq_send); |
536 | |
537 | /** |
538 | * fc_seq_alloc() - Allocate a sequence for a given exchange |
539 | * @ep: The exchange to allocate a new sequence for |
540 | * @seq_id: The sequence ID to be used |
541 | * |
542 | * We don't support multiple originated sequences on the same exchange. |
543 | * By implication, any previously originated sequence on this exchange |
544 | * is complete, and we reallocate the same sequence. |
545 | */ |
546 | static struct fc_seq *fc_seq_alloc(struct fc_exch *ep, u8 seq_id) |
547 | { |
548 | struct fc_seq *sp; |
549 | |
550 | sp = &ep->seq; |
551 | sp->ssb_stat = 0; |
552 | sp->cnt = 0; |
553 | sp->id = seq_id; |
554 | return sp; |
555 | } |
556 | |
557 | /** |
558 | * fc_seq_start_next_locked() - Allocate a new sequence on the same |
559 | * exchange as the supplied sequence |
560 | * @sp: The sequence/exchange to get a new sequence for |
561 | */ |
562 | static struct fc_seq *fc_seq_start_next_locked(struct fc_seq *sp) |
563 | { |
564 | struct fc_exch *ep = fc_seq_exch(sp); |
565 | |
566 | sp = fc_seq_alloc(ep, seq_id: ep->seq_id++); |
567 | FC_EXCH_DBG(ep, "f_ctl %6x seq %2x\n" , |
568 | ep->f_ctl, sp->id); |
569 | return sp; |
570 | } |
571 | |
572 | /** |
573 | * fc_seq_start_next() - Lock the exchange and get a new sequence |
574 | * for a given sequence/exchange pair |
575 | * @sp: The sequence/exchange to get a new exchange for |
576 | */ |
577 | struct fc_seq *fc_seq_start_next(struct fc_seq *sp) |
578 | { |
579 | struct fc_exch *ep = fc_seq_exch(sp); |
580 | |
581 | spin_lock_bh(lock: &ep->ex_lock); |
582 | sp = fc_seq_start_next_locked(sp); |
583 | spin_unlock_bh(lock: &ep->ex_lock); |
584 | |
585 | return sp; |
586 | } |
587 | EXPORT_SYMBOL(fc_seq_start_next); |
588 | |
589 | /* |
590 | * Set the response handler for the exchange associated with a sequence. |
591 | * |
592 | * Note: May sleep if invoked from outside a response handler. |
593 | */ |
594 | void fc_seq_set_resp(struct fc_seq *sp, |
595 | void (*resp)(struct fc_seq *, struct fc_frame *, void *), |
596 | void *arg) |
597 | { |
598 | struct fc_exch *ep = fc_seq_exch(sp); |
599 | DEFINE_WAIT(wait); |
600 | |
601 | spin_lock_bh(lock: &ep->ex_lock); |
602 | while (ep->resp_active && ep->resp_task != current) { |
603 | prepare_to_wait(wq_head: &ep->resp_wq, wq_entry: &wait, TASK_UNINTERRUPTIBLE); |
604 | spin_unlock_bh(lock: &ep->ex_lock); |
605 | |
606 | schedule(); |
607 | |
608 | spin_lock_bh(lock: &ep->ex_lock); |
609 | } |
610 | finish_wait(wq_head: &ep->resp_wq, wq_entry: &wait); |
611 | ep->resp = resp; |
612 | ep->arg = arg; |
613 | spin_unlock_bh(lock: &ep->ex_lock); |
614 | } |
615 | EXPORT_SYMBOL(fc_seq_set_resp); |
616 | |
617 | /** |
618 | * fc_exch_abort_locked() - Abort an exchange |
619 | * @ep: The exchange to be aborted |
620 | * @timer_msec: The period of time to wait before aborting |
621 | * |
622 | * Abort an exchange and sequence. Generally called because of a |
623 | * exchange timeout or an abort from the upper layer. |
624 | * |
625 | * A timer_msec can be specified for abort timeout, if non-zero |
626 | * timer_msec value is specified then exchange resp handler |
627 | * will be called with timeout error if no response to abort. |
628 | * |
629 | * Locking notes: Called with exch lock held |
630 | * |
631 | * Return value: 0 on success else error code |
632 | */ |
633 | static int fc_exch_abort_locked(struct fc_exch *ep, |
634 | unsigned int timer_msec) |
635 | { |
636 | struct fc_seq *sp; |
637 | struct fc_frame *fp; |
638 | int error; |
639 | |
640 | FC_EXCH_DBG(ep, "exch: abort, time %d msecs\n" , timer_msec); |
641 | if (ep->esb_stat & (ESB_ST_COMPLETE | ESB_ST_ABNORMAL) || |
642 | ep->state & (FC_EX_DONE | FC_EX_RST_CLEANUP)) { |
643 | FC_EXCH_DBG(ep, "exch: already completed esb %x state %x\n" , |
644 | ep->esb_stat, ep->state); |
645 | return -ENXIO; |
646 | } |
647 | |
648 | /* |
649 | * Send the abort on a new sequence if possible. |
650 | */ |
651 | sp = fc_seq_start_next_locked(sp: &ep->seq); |
652 | if (!sp) |
653 | return -ENOMEM; |
654 | |
655 | if (timer_msec) |
656 | fc_exch_timer_set_locked(ep, timer_msec); |
657 | |
658 | if (ep->sid) { |
659 | /* |
660 | * Send an abort for the sequence that timed out. |
661 | */ |
662 | fp = fc_frame_alloc(dev: ep->lp, len: 0); |
663 | if (fp) { |
664 | ep->esb_stat |= ESB_ST_SEQ_INIT; |
665 | fc_fill_fc_hdr(fp, r_ctl: FC_RCTL_BA_ABTS, did: ep->did, sid: ep->sid, |
666 | type: FC_TYPE_BLS, FC_FC_END_SEQ | |
667 | FC_FC_SEQ_INIT, parm_offset: 0); |
668 | error = fc_seq_send_locked(lport: ep->lp, sp, fp); |
669 | } else { |
670 | error = -ENOBUFS; |
671 | } |
672 | } else { |
673 | /* |
674 | * If not logged into the fabric, don't send ABTS but leave |
675 | * sequence active until next timeout. |
676 | */ |
677 | error = 0; |
678 | } |
679 | ep->esb_stat |= ESB_ST_ABNORMAL; |
680 | return error; |
681 | } |
682 | |
683 | /** |
684 | * fc_seq_exch_abort() - Abort an exchange and sequence |
685 | * @req_sp: The sequence to be aborted |
686 | * @timer_msec: The period of time to wait before aborting |
687 | * |
688 | * Generally called because of a timeout or an abort from the upper layer. |
689 | * |
690 | * Return value: 0 on success else error code |
691 | */ |
692 | int fc_seq_exch_abort(const struct fc_seq *req_sp, unsigned int timer_msec) |
693 | { |
694 | struct fc_exch *ep; |
695 | int error; |
696 | |
697 | ep = fc_seq_exch(req_sp); |
698 | spin_lock_bh(lock: &ep->ex_lock); |
699 | error = fc_exch_abort_locked(ep, timer_msec); |
700 | spin_unlock_bh(lock: &ep->ex_lock); |
701 | return error; |
702 | } |
703 | |
704 | /** |
705 | * fc_invoke_resp() - invoke ep->resp() |
706 | * @ep: The exchange to be operated on |
707 | * @fp: The frame pointer to pass through to ->resp() |
708 | * @sp: The sequence pointer to pass through to ->resp() |
709 | * |
710 | * Notes: |
711 | * It is assumed that after initialization finished (this means the |
712 | * first unlock of ex_lock after fc_exch_alloc()) ep->resp and ep->arg are |
713 | * modified only via fc_seq_set_resp(). This guarantees that none of these |
714 | * two variables changes if ep->resp_active > 0. |
715 | * |
716 | * If an fc_seq_set_resp() call is busy modifying ep->resp and ep->arg when |
717 | * this function is invoked, the first spin_lock_bh() call in this function |
718 | * will wait until fc_seq_set_resp() has finished modifying these variables. |
719 | * |
720 | * Since fc_exch_done() invokes fc_seq_set_resp() it is guaranteed that that |
721 | * ep->resp() won't be invoked after fc_exch_done() has returned. |
722 | * |
723 | * The response handler itself may invoke fc_exch_done(), which will clear the |
724 | * ep->resp pointer. |
725 | * |
726 | * Return value: |
727 | * Returns true if and only if ep->resp has been invoked. |
728 | */ |
729 | static bool fc_invoke_resp(struct fc_exch *ep, struct fc_seq *sp, |
730 | struct fc_frame *fp) |
731 | { |
732 | void (*resp)(struct fc_seq *, struct fc_frame *fp, void *arg); |
733 | void *arg; |
734 | bool res = false; |
735 | |
736 | spin_lock_bh(lock: &ep->ex_lock); |
737 | ep->resp_active++; |
738 | if (ep->resp_task != current) |
739 | ep->resp_task = !ep->resp_task ? current : NULL; |
740 | resp = ep->resp; |
741 | arg = ep->arg; |
742 | spin_unlock_bh(lock: &ep->ex_lock); |
743 | |
744 | if (resp) { |
745 | resp(sp, fp, arg); |
746 | res = true; |
747 | } |
748 | |
749 | spin_lock_bh(lock: &ep->ex_lock); |
750 | if (--ep->resp_active == 0) |
751 | ep->resp_task = NULL; |
752 | spin_unlock_bh(lock: &ep->ex_lock); |
753 | |
754 | if (ep->resp_active == 0) |
755 | wake_up(&ep->resp_wq); |
756 | |
757 | return res; |
758 | } |
759 | |
760 | /** |
761 | * fc_exch_timeout() - Handle exchange timer expiration |
762 | * @work: The work_struct identifying the exchange that timed out |
763 | */ |
764 | static void fc_exch_timeout(struct work_struct *work) |
765 | { |
766 | struct fc_exch *ep = container_of(work, struct fc_exch, |
767 | timeout_work.work); |
768 | struct fc_seq *sp = &ep->seq; |
769 | u32 e_stat; |
770 | int rc = 1; |
771 | |
772 | FC_EXCH_DBG(ep, "Exchange timed out state %x\n" , ep->state); |
773 | |
774 | spin_lock_bh(lock: &ep->ex_lock); |
775 | if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) |
776 | goto unlock; |
777 | |
778 | e_stat = ep->esb_stat; |
779 | if (e_stat & ESB_ST_COMPLETE) { |
780 | ep->esb_stat = e_stat & ~ESB_ST_REC_QUAL; |
781 | spin_unlock_bh(lock: &ep->ex_lock); |
782 | if (e_stat & ESB_ST_REC_QUAL) |
783 | fc_exch_rrq(ep); |
784 | goto done; |
785 | } else { |
786 | if (e_stat & ESB_ST_ABNORMAL) |
787 | rc = fc_exch_done_locked(ep); |
788 | spin_unlock_bh(lock: &ep->ex_lock); |
789 | if (!rc) |
790 | fc_exch_delete(ep); |
791 | fc_invoke_resp(ep, sp, fp: ERR_PTR(error: -FC_EX_TIMEOUT)); |
792 | fc_seq_set_resp(sp, NULL, ep->arg); |
793 | fc_seq_exch_abort(req_sp: sp, timer_msec: 2 * ep->r_a_tov); |
794 | goto done; |
795 | } |
796 | unlock: |
797 | spin_unlock_bh(lock: &ep->ex_lock); |
798 | done: |
799 | /* |
800 | * This release matches the hold taken when the timer was set. |
801 | */ |
802 | fc_exch_release(ep); |
803 | } |
804 | |
805 | /** |
806 | * fc_exch_em_alloc() - Allocate an exchange from a specified EM. |
807 | * @lport: The local port that the exchange is for |
808 | * @mp: The exchange manager that will allocate the exchange |
809 | * |
810 | * Returns pointer to allocated fc_exch with exch lock held. |
811 | */ |
812 | static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport, |
813 | struct fc_exch_mgr *mp) |
814 | { |
815 | struct fc_exch *ep; |
816 | unsigned int cpu; |
817 | u16 index; |
818 | struct fc_exch_pool *pool; |
819 | |
820 | /* allocate memory for exchange */ |
821 | ep = mempool_alloc(pool: mp->ep_pool, GFP_ATOMIC); |
822 | if (!ep) { |
823 | atomic_inc(v: &mp->stats.no_free_exch); |
824 | goto out; |
825 | } |
826 | memset(ep, 0, sizeof(*ep)); |
827 | |
828 | cpu = raw_smp_processor_id(); |
829 | pool = per_cpu_ptr(mp->pool, cpu); |
830 | spin_lock_bh(lock: &pool->lock); |
831 | |
832 | /* peek cache of free slot */ |
833 | if (pool->left != FC_XID_UNKNOWN) { |
834 | if (!WARN_ON(fc_exch_ptr_get(pool, pool->left))) { |
835 | index = pool->left; |
836 | pool->left = FC_XID_UNKNOWN; |
837 | goto hit; |
838 | } |
839 | } |
840 | if (pool->right != FC_XID_UNKNOWN) { |
841 | if (!WARN_ON(fc_exch_ptr_get(pool, pool->right))) { |
842 | index = pool->right; |
843 | pool->right = FC_XID_UNKNOWN; |
844 | goto hit; |
845 | } |
846 | } |
847 | |
848 | index = pool->next_index; |
849 | /* allocate new exch from pool */ |
850 | while (fc_exch_ptr_get(pool, index)) { |
851 | index = index == mp->pool_max_index ? 0 : index + 1; |
852 | if (index == pool->next_index) |
853 | goto err; |
854 | } |
855 | pool->next_index = index == mp->pool_max_index ? 0 : index + 1; |
856 | hit: |
857 | fc_exch_hold(ep); /* hold for exch in mp */ |
858 | spin_lock_init(&ep->ex_lock); |
859 | /* |
860 | * Hold exch lock for caller to prevent fc_exch_reset() |
861 | * from releasing exch while fc_exch_alloc() caller is |
862 | * still working on exch. |
863 | */ |
864 | spin_lock_bh(lock: &ep->ex_lock); |
865 | |
866 | fc_exch_ptr_set(pool, index, ep); |
867 | list_add_tail(new: &ep->ex_list, head: &pool->ex_list); |
868 | fc_seq_alloc(ep, seq_id: ep->seq_id++); |
869 | pool->total_exches++; |
870 | spin_unlock_bh(lock: &pool->lock); |
871 | |
872 | /* |
873 | * update exchange |
874 | */ |
875 | ep->oxid = ep->xid = (index << fc_cpu_order | cpu) + mp->min_xid; |
876 | ep->em = mp; |
877 | ep->pool = pool; |
878 | ep->lp = lport; |
879 | ep->f_ctl = FC_FC_FIRST_SEQ; /* next seq is first seq */ |
880 | ep->rxid = FC_XID_UNKNOWN; |
881 | ep->class = mp->class; |
882 | ep->resp_active = 0; |
883 | init_waitqueue_head(&ep->resp_wq); |
884 | INIT_DELAYED_WORK(&ep->timeout_work, fc_exch_timeout); |
885 | out: |
886 | return ep; |
887 | err: |
888 | spin_unlock_bh(lock: &pool->lock); |
889 | atomic_inc(v: &mp->stats.no_free_exch_xid); |
890 | mempool_free(element: ep, pool: mp->ep_pool); |
891 | return NULL; |
892 | } |
893 | |
894 | /** |
895 | * fc_exch_alloc() - Allocate an exchange from an EM on a |
896 | * local port's list of EMs. |
897 | * @lport: The local port that will own the exchange |
898 | * @fp: The FC frame that the exchange will be for |
899 | * |
900 | * This function walks the list of exchange manager(EM) |
901 | * anchors to select an EM for a new exchange allocation. The |
902 | * EM is selected when a NULL match function pointer is encountered |
903 | * or when a call to a match function returns true. |
904 | */ |
905 | static struct fc_exch *fc_exch_alloc(struct fc_lport *lport, |
906 | struct fc_frame *fp) |
907 | { |
908 | struct fc_exch_mgr_anchor *ema; |
909 | struct fc_exch *ep; |
910 | |
911 | list_for_each_entry(ema, &lport->ema_list, ema_list) { |
912 | if (!ema->match || ema->match(fp)) { |
913 | ep = fc_exch_em_alloc(lport, mp: ema->mp); |
914 | if (ep) |
915 | return ep; |
916 | } |
917 | } |
918 | return NULL; |
919 | } |
920 | |
921 | /** |
922 | * fc_exch_find() - Lookup and hold an exchange |
923 | * @mp: The exchange manager to lookup the exchange from |
924 | * @xid: The XID of the exchange to look up |
925 | */ |
926 | static struct fc_exch *fc_exch_find(struct fc_exch_mgr *mp, u16 xid) |
927 | { |
928 | struct fc_lport *lport = mp->lport; |
929 | struct fc_exch_pool *pool; |
930 | struct fc_exch *ep = NULL; |
931 | u16 cpu = xid & fc_cpu_mask; |
932 | |
933 | if (xid == FC_XID_UNKNOWN) |
934 | return NULL; |
935 | |
936 | if (cpu >= nr_cpu_ids || !cpu_possible(cpu)) { |
937 | pr_err("host%u: lport %6.6x: xid %d invalid CPU %d\n:" , |
938 | lport->host->host_no, lport->port_id, xid, cpu); |
939 | return NULL; |
940 | } |
941 | |
942 | if ((xid >= mp->min_xid) && (xid <= mp->max_xid)) { |
943 | pool = per_cpu_ptr(mp->pool, cpu); |
944 | spin_lock_bh(lock: &pool->lock); |
945 | ep = fc_exch_ptr_get(pool, index: (xid - mp->min_xid) >> fc_cpu_order); |
946 | if (ep == &fc_quarantine_exch) { |
947 | FC_LPORT_DBG(lport, "xid %x quarantined\n" , xid); |
948 | ep = NULL; |
949 | } |
950 | if (ep) { |
951 | WARN_ON(ep->xid != xid); |
952 | fc_exch_hold(ep); |
953 | } |
954 | spin_unlock_bh(lock: &pool->lock); |
955 | } |
956 | return ep; |
957 | } |
958 | |
959 | |
960 | /** |
961 | * fc_exch_done() - Indicate that an exchange/sequence tuple is complete and |
962 | * the memory allocated for the related objects may be freed. |
963 | * @sp: The sequence that has completed |
964 | * |
965 | * Note: May sleep if invoked from outside a response handler. |
966 | */ |
967 | void fc_exch_done(struct fc_seq *sp) |
968 | { |
969 | struct fc_exch *ep = fc_seq_exch(sp); |
970 | int rc; |
971 | |
972 | spin_lock_bh(lock: &ep->ex_lock); |
973 | rc = fc_exch_done_locked(ep); |
974 | spin_unlock_bh(lock: &ep->ex_lock); |
975 | |
976 | fc_seq_set_resp(sp, NULL, ep->arg); |
977 | if (!rc) |
978 | fc_exch_delete(ep); |
979 | } |
980 | EXPORT_SYMBOL(fc_exch_done); |
981 | |
982 | /** |
983 | * fc_exch_resp() - Allocate a new exchange for a response frame |
984 | * @lport: The local port that the exchange was for |
985 | * @mp: The exchange manager to allocate the exchange from |
986 | * @fp: The response frame |
987 | * |
988 | * Sets the responder ID in the frame header. |
989 | */ |
990 | static struct fc_exch *fc_exch_resp(struct fc_lport *lport, |
991 | struct fc_exch_mgr *mp, |
992 | struct fc_frame *fp) |
993 | { |
994 | struct fc_exch *ep; |
995 | struct fc_frame_header *fh; |
996 | |
997 | ep = fc_exch_alloc(lport, fp); |
998 | if (ep) { |
999 | ep->class = fc_frame_class(fp); |
1000 | |
1001 | /* |
1002 | * Set EX_CTX indicating we're responding on this exchange. |
1003 | */ |
1004 | ep->f_ctl |= FC_FC_EX_CTX; /* we're responding */ |
1005 | ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not new */ |
1006 | fh = fc_frame_header_get(fp); |
1007 | ep->sid = ntoh24(p: fh->fh_d_id); |
1008 | ep->did = ntoh24(p: fh->fh_s_id); |
1009 | ep->oid = ep->did; |
1010 | |
1011 | /* |
1012 | * Allocated exchange has placed the XID in the |
1013 | * originator field. Move it to the responder field, |
1014 | * and set the originator XID from the frame. |
1015 | */ |
1016 | ep->rxid = ep->xid; |
1017 | ep->oxid = ntohs(fh->fh_ox_id); |
1018 | ep->esb_stat |= ESB_ST_RESP | ESB_ST_SEQ_INIT; |
1019 | if ((ntoh24(p: fh->fh_f_ctl) & FC_FC_SEQ_INIT) == 0) |
1020 | ep->esb_stat &= ~ESB_ST_SEQ_INIT; |
1021 | |
1022 | fc_exch_hold(ep); /* hold for caller */ |
1023 | spin_unlock_bh(lock: &ep->ex_lock); /* lock from fc_exch_alloc */ |
1024 | } |
1025 | return ep; |
1026 | } |
1027 | |
1028 | /** |
1029 | * fc_seq_lookup_recip() - Find a sequence where the other end |
1030 | * originated the sequence |
1031 | * @lport: The local port that the frame was sent to |
1032 | * @mp: The Exchange Manager to lookup the exchange from |
1033 | * @fp: The frame associated with the sequence we're looking for |
1034 | * |
1035 | * If fc_pf_rjt_reason is FC_RJT_NONE then this function will have a hold |
1036 | * on the ep that should be released by the caller. |
1037 | */ |
1038 | static enum fc_pf_rjt_reason fc_seq_lookup_recip(struct fc_lport *lport, |
1039 | struct fc_exch_mgr *mp, |
1040 | struct fc_frame *fp) |
1041 | { |
1042 | struct fc_frame_header *fh = fc_frame_header_get(fp); |
1043 | struct fc_exch *ep = NULL; |
1044 | struct fc_seq *sp = NULL; |
1045 | enum fc_pf_rjt_reason reject = FC_RJT_NONE; |
1046 | u32 f_ctl; |
1047 | u16 xid; |
1048 | |
1049 | f_ctl = ntoh24(p: fh->fh_f_ctl); |
1050 | WARN_ON((f_ctl & FC_FC_SEQ_CTX) != 0); |
1051 | |
1052 | /* |
1053 | * Lookup or create the exchange if we will be creating the sequence. |
1054 | */ |
1055 | if (f_ctl & FC_FC_EX_CTX) { |
1056 | xid = ntohs(fh->fh_ox_id); /* we originated exch */ |
1057 | ep = fc_exch_find(mp, xid); |
1058 | if (!ep) { |
1059 | atomic_inc(v: &mp->stats.xid_not_found); |
1060 | reject = FC_RJT_OX_ID; |
1061 | goto out; |
1062 | } |
1063 | if (ep->rxid == FC_XID_UNKNOWN) |
1064 | ep->rxid = ntohs(fh->fh_rx_id); |
1065 | else if (ep->rxid != ntohs(fh->fh_rx_id)) { |
1066 | reject = FC_RJT_OX_ID; |
1067 | goto rel; |
1068 | } |
1069 | } else { |
1070 | xid = ntohs(fh->fh_rx_id); /* we are the responder */ |
1071 | |
1072 | /* |
1073 | * Special case for MDS issuing an ELS TEST with a |
1074 | * bad rxid of 0. |
1075 | * XXX take this out once we do the proper reject. |
1076 | */ |
1077 | if (xid == 0 && fh->fh_r_ctl == FC_RCTL_ELS_REQ && |
1078 | fc_frame_payload_op(fp) == ELS_TEST) { |
1079 | fh->fh_rx_id = htons(FC_XID_UNKNOWN); |
1080 | xid = FC_XID_UNKNOWN; |
1081 | } |
1082 | |
1083 | /* |
1084 | * new sequence - find the exchange |
1085 | */ |
1086 | ep = fc_exch_find(mp, xid); |
1087 | if ((f_ctl & FC_FC_FIRST_SEQ) && fc_sof_is_init(fr_sof(fp))) { |
1088 | if (ep) { |
1089 | atomic_inc(v: &mp->stats.xid_busy); |
1090 | reject = FC_RJT_RX_ID; |
1091 | goto rel; |
1092 | } |
1093 | ep = fc_exch_resp(lport, mp, fp); |
1094 | if (!ep) { |
1095 | reject = FC_RJT_EXCH_EST; /* XXX */ |
1096 | goto out; |
1097 | } |
1098 | xid = ep->xid; /* get our XID */ |
1099 | } else if (!ep) { |
1100 | atomic_inc(v: &mp->stats.xid_not_found); |
1101 | reject = FC_RJT_RX_ID; /* XID not found */ |
1102 | goto out; |
1103 | } |
1104 | } |
1105 | |
1106 | spin_lock_bh(lock: &ep->ex_lock); |
1107 | /* |
1108 | * At this point, we have the exchange held. |
1109 | * Find or create the sequence. |
1110 | */ |
1111 | if (fc_sof_is_init(fr_sof(fp))) { |
1112 | sp = &ep->seq; |
1113 | sp->ssb_stat |= SSB_ST_RESP; |
1114 | sp->id = fh->fh_seq_id; |
1115 | } else { |
1116 | sp = &ep->seq; |
1117 | if (sp->id != fh->fh_seq_id) { |
1118 | atomic_inc(v: &mp->stats.seq_not_found); |
1119 | if (f_ctl & FC_FC_END_SEQ) { |
1120 | /* |
1121 | * Update sequence_id based on incoming last |
1122 | * frame of sequence exchange. This is needed |
1123 | * for FC target where DDP has been used |
1124 | * on target where, stack is indicated only |
1125 | * about last frame's (payload _header) header. |
1126 | * Whereas "seq_id" which is part of |
1127 | * frame_header is allocated by initiator |
1128 | * which is totally different from "seq_id" |
1129 | * allocated when XFER_RDY was sent by target. |
1130 | * To avoid false -ve which results into not |
1131 | * sending RSP, hence write request on other |
1132 | * end never finishes. |
1133 | */ |
1134 | sp->ssb_stat |= SSB_ST_RESP; |
1135 | sp->id = fh->fh_seq_id; |
1136 | } else { |
1137 | spin_unlock_bh(lock: &ep->ex_lock); |
1138 | |
1139 | /* sequence/exch should exist */ |
1140 | reject = FC_RJT_SEQ_ID; |
1141 | goto rel; |
1142 | } |
1143 | } |
1144 | } |
1145 | WARN_ON(ep != fc_seq_exch(sp)); |
1146 | |
1147 | if (f_ctl & FC_FC_SEQ_INIT) |
1148 | ep->esb_stat |= ESB_ST_SEQ_INIT; |
1149 | spin_unlock_bh(lock: &ep->ex_lock); |
1150 | |
1151 | fr_seq(fp) = sp; |
1152 | out: |
1153 | return reject; |
1154 | rel: |
1155 | fc_exch_done(&ep->seq); |
1156 | fc_exch_release(ep); /* hold from fc_exch_find/fc_exch_resp */ |
1157 | return reject; |
1158 | } |
1159 | |
1160 | /** |
1161 | * fc_seq_lookup_orig() - Find a sequence where this end |
1162 | * originated the sequence |
1163 | * @mp: The Exchange Manager to lookup the exchange from |
1164 | * @fp: The frame associated with the sequence we're looking for |
1165 | * |
1166 | * Does not hold the sequence for the caller. |
1167 | */ |
1168 | static struct fc_seq *fc_seq_lookup_orig(struct fc_exch_mgr *mp, |
1169 | struct fc_frame *fp) |
1170 | { |
1171 | struct fc_frame_header *fh = fc_frame_header_get(fp); |
1172 | struct fc_exch *ep; |
1173 | struct fc_seq *sp = NULL; |
1174 | u32 f_ctl; |
1175 | u16 xid; |
1176 | |
1177 | f_ctl = ntoh24(p: fh->fh_f_ctl); |
1178 | WARN_ON((f_ctl & FC_FC_SEQ_CTX) != FC_FC_SEQ_CTX); |
1179 | xid = ntohs((f_ctl & FC_FC_EX_CTX) ? fh->fh_ox_id : fh->fh_rx_id); |
1180 | ep = fc_exch_find(mp, xid); |
1181 | if (!ep) |
1182 | return NULL; |
1183 | if (ep->seq.id == fh->fh_seq_id) { |
1184 | /* |
1185 | * Save the RX_ID if we didn't previously know it. |
1186 | */ |
1187 | sp = &ep->seq; |
1188 | if ((f_ctl & FC_FC_EX_CTX) != 0 && |
1189 | ep->rxid == FC_XID_UNKNOWN) { |
1190 | ep->rxid = ntohs(fh->fh_rx_id); |
1191 | } |
1192 | } |
1193 | fc_exch_release(ep); |
1194 | return sp; |
1195 | } |
1196 | |
1197 | /** |
1198 | * fc_exch_set_addr() - Set the source and destination IDs for an exchange |
1199 | * @ep: The exchange to set the addresses for |
1200 | * @orig_id: The originator's ID |
1201 | * @resp_id: The responder's ID |
1202 | * |
1203 | * Note this must be done before the first sequence of the exchange is sent. |
1204 | */ |
1205 | static void fc_exch_set_addr(struct fc_exch *ep, |
1206 | u32 orig_id, u32 resp_id) |
1207 | { |
1208 | ep->oid = orig_id; |
1209 | if (ep->esb_stat & ESB_ST_RESP) { |
1210 | ep->sid = resp_id; |
1211 | ep->did = orig_id; |
1212 | } else { |
1213 | ep->sid = orig_id; |
1214 | ep->did = resp_id; |
1215 | } |
1216 | } |
1217 | |
1218 | /** |
1219 | * fc_seq_els_rsp_send() - Send an ELS response using information from |
1220 | * the existing sequence/exchange. |
1221 | * @fp: The received frame |
1222 | * @els_cmd: The ELS command to be sent |
1223 | * @els_data: The ELS data to be sent |
1224 | * |
1225 | * The received frame is not freed. |
1226 | */ |
1227 | void fc_seq_els_rsp_send(struct fc_frame *fp, enum fc_els_cmd els_cmd, |
1228 | struct fc_seq_els_data *els_data) |
1229 | { |
1230 | switch (els_cmd) { |
1231 | case ELS_LS_RJT: |
1232 | fc_seq_ls_rjt(fp, els_data->reason, els_data->explan); |
1233 | break; |
1234 | case ELS_LS_ACC: |
1235 | fc_seq_ls_acc(fp); |
1236 | break; |
1237 | case ELS_RRQ: |
1238 | fc_exch_els_rrq(fp); |
1239 | break; |
1240 | case ELS_REC: |
1241 | fc_exch_els_rec(fp); |
1242 | break; |
1243 | default: |
1244 | FC_LPORT_DBG(fr_dev(fp), "Invalid ELS CMD:%x\n" , els_cmd); |
1245 | } |
1246 | } |
1247 | EXPORT_SYMBOL_GPL(fc_seq_els_rsp_send); |
1248 | |
1249 | /** |
1250 | * fc_seq_send_last() - Send a sequence that is the last in the exchange |
1251 | * @sp: The sequence that is to be sent |
1252 | * @fp: The frame that will be sent on the sequence |
1253 | * @rctl: The R_CTL information to be sent |
1254 | * @fh_type: The frame header type |
1255 | */ |
1256 | static void fc_seq_send_last(struct fc_seq *sp, struct fc_frame *fp, |
1257 | enum fc_rctl rctl, enum fc_fh_type fh_type) |
1258 | { |
1259 | u32 f_ctl; |
1260 | struct fc_exch *ep = fc_seq_exch(sp); |
1261 | |
1262 | f_ctl = FC_FC_LAST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT; |
1263 | f_ctl |= ep->f_ctl; |
1264 | fc_fill_fc_hdr(fp, r_ctl: rctl, did: ep->did, sid: ep->sid, type: fh_type, f_ctl, parm_offset: 0); |
1265 | fc_seq_send_locked(lport: ep->lp, sp, fp); |
1266 | } |
1267 | |
1268 | /** |
1269 | * fc_seq_send_ack() - Send an acknowledgement that we've received a frame |
1270 | * @sp: The sequence to send the ACK on |
1271 | * @rx_fp: The received frame that is being acknoledged |
1272 | * |
1273 | * Send ACK_1 (or equiv.) indicating we received something. |
1274 | */ |
1275 | static void fc_seq_send_ack(struct fc_seq *sp, const struct fc_frame *rx_fp) |
1276 | { |
1277 | struct fc_frame *fp; |
1278 | struct fc_frame_header *rx_fh; |
1279 | struct fc_frame_header *fh; |
1280 | struct fc_exch *ep = fc_seq_exch(sp); |
1281 | struct fc_lport *lport = ep->lp; |
1282 | unsigned int f_ctl; |
1283 | |
1284 | /* |
1285 | * Don't send ACKs for class 3. |
1286 | */ |
1287 | if (fc_sof_needs_ack(fr_sof(rx_fp))) { |
1288 | fp = fc_frame_alloc(dev: lport, len: 0); |
1289 | if (!fp) { |
1290 | FC_EXCH_DBG(ep, "Drop ACK request, out of memory\n" ); |
1291 | return; |
1292 | } |
1293 | |
1294 | fh = fc_frame_header_get(fp); |
1295 | fh->fh_r_ctl = FC_RCTL_ACK_1; |
1296 | fh->fh_type = FC_TYPE_BLS; |
1297 | |
1298 | /* |
1299 | * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22). |
1300 | * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT. |
1301 | * Bits 9-8 are meaningful (retransmitted or unidirectional). |
1302 | * Last ACK uses bits 7-6 (continue sequence), |
1303 | * bits 5-4 are meaningful (what kind of ACK to use). |
1304 | */ |
1305 | rx_fh = fc_frame_header_get(fp: rx_fp); |
1306 | f_ctl = ntoh24(p: rx_fh->fh_f_ctl); |
1307 | f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX | |
1308 | FC_FC_FIRST_SEQ | FC_FC_LAST_SEQ | |
1309 | FC_FC_END_SEQ | FC_FC_END_CONN | FC_FC_SEQ_INIT | |
1310 | FC_FC_RETX_SEQ | FC_FC_UNI_TX; |
1311 | f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX; |
1312 | hton24(p: fh->fh_f_ctl, v: f_ctl); |
1313 | |
1314 | fc_exch_setup_hdr(ep, fp, f_ctl); |
1315 | fh->fh_seq_id = rx_fh->fh_seq_id; |
1316 | fh->fh_seq_cnt = rx_fh->fh_seq_cnt; |
1317 | fh->fh_parm_offset = htonl(1); /* ack single frame */ |
1318 | |
1319 | fr_sof(fp) = fr_sof(rx_fp); |
1320 | if (f_ctl & FC_FC_END_SEQ) |
1321 | fr_eof(fp) = FC_EOF_T; |
1322 | else |
1323 | fr_eof(fp) = FC_EOF_N; |
1324 | |
1325 | lport->tt.frame_send(lport, fp); |
1326 | } |
1327 | } |
1328 | |
1329 | /** |
1330 | * fc_exch_send_ba_rjt() - Send BLS Reject |
1331 | * @rx_fp: The frame being rejected |
1332 | * @reason: The reason the frame is being rejected |
1333 | * @explan: The explanation for the rejection |
1334 | * |
1335 | * This is for rejecting BA_ABTS only. |
1336 | */ |
1337 | static void fc_exch_send_ba_rjt(struct fc_frame *rx_fp, |
1338 | enum fc_ba_rjt_reason reason, |
1339 | enum fc_ba_rjt_explan explan) |
1340 | { |
1341 | struct fc_frame *fp; |
1342 | struct fc_frame_header *rx_fh; |
1343 | struct fc_frame_header *fh; |
1344 | struct fc_ba_rjt *rp; |
1345 | struct fc_seq *sp; |
1346 | struct fc_lport *lport; |
1347 | unsigned int f_ctl; |
1348 | |
1349 | lport = fr_dev(rx_fp); |
1350 | sp = fr_seq(rx_fp); |
1351 | fp = fc_frame_alloc(dev: lport, len: sizeof(*rp)); |
1352 | if (!fp) { |
1353 | FC_EXCH_DBG(fc_seq_exch(sp), |
1354 | "Drop BA_RJT request, out of memory\n" ); |
1355 | return; |
1356 | } |
1357 | fh = fc_frame_header_get(fp); |
1358 | rx_fh = fc_frame_header_get(fp: rx_fp); |
1359 | |
1360 | memset(fh, 0, sizeof(*fh) + sizeof(*rp)); |
1361 | |
1362 | rp = fc_frame_payload_get(fp, len: sizeof(*rp)); |
1363 | rp->br_reason = reason; |
1364 | rp->br_explan = explan; |
1365 | |
1366 | /* |
1367 | * seq_id, cs_ctl, df_ctl and param/offset are zero. |
1368 | */ |
1369 | memcpy(fh->fh_s_id, rx_fh->fh_d_id, 3); |
1370 | memcpy(fh->fh_d_id, rx_fh->fh_s_id, 3); |
1371 | fh->fh_ox_id = rx_fh->fh_ox_id; |
1372 | fh->fh_rx_id = rx_fh->fh_rx_id; |
1373 | fh->fh_seq_cnt = rx_fh->fh_seq_cnt; |
1374 | fh->fh_r_ctl = FC_RCTL_BA_RJT; |
1375 | fh->fh_type = FC_TYPE_BLS; |
1376 | |
1377 | /* |
1378 | * Form f_ctl by inverting EX_CTX and SEQ_CTX (bits 23, 22). |
1379 | * Echo FIRST_SEQ, LAST_SEQ, END_SEQ, END_CONN, SEQ_INIT. |
1380 | * Bits 9-8 are meaningful (retransmitted or unidirectional). |
1381 | * Last ACK uses bits 7-6 (continue sequence), |
1382 | * bits 5-4 are meaningful (what kind of ACK to use). |
1383 | * Always set LAST_SEQ, END_SEQ. |
1384 | */ |
1385 | f_ctl = ntoh24(p: rx_fh->fh_f_ctl); |
1386 | f_ctl &= FC_FC_EX_CTX | FC_FC_SEQ_CTX | |
1387 | FC_FC_END_CONN | FC_FC_SEQ_INIT | |
1388 | FC_FC_RETX_SEQ | FC_FC_UNI_TX; |
1389 | f_ctl ^= FC_FC_EX_CTX | FC_FC_SEQ_CTX; |
1390 | f_ctl |= FC_FC_LAST_SEQ | FC_FC_END_SEQ; |
1391 | f_ctl &= ~FC_FC_FIRST_SEQ; |
1392 | hton24(p: fh->fh_f_ctl, v: f_ctl); |
1393 | |
1394 | fr_sof(fp) = fc_sof_class(fr_sof(rx_fp)); |
1395 | fr_eof(fp) = FC_EOF_T; |
1396 | if (fc_sof_needs_ack(fr_sof(fp))) |
1397 | fr_eof(fp) = FC_EOF_N; |
1398 | |
1399 | lport->tt.frame_send(lport, fp); |
1400 | } |
1401 | |
1402 | /** |
1403 | * fc_exch_recv_abts() - Handle an incoming ABTS |
1404 | * @ep: The exchange the abort was on |
1405 | * @rx_fp: The ABTS frame |
1406 | * |
1407 | * This would be for target mode usually, but could be due to lost |
1408 | * FCP transfer ready, confirm or RRQ. We always handle this as an |
1409 | * exchange abort, ignoring the parameter. |
1410 | */ |
1411 | static void fc_exch_recv_abts(struct fc_exch *ep, struct fc_frame *rx_fp) |
1412 | { |
1413 | struct fc_frame *fp; |
1414 | struct fc_ba_acc *ap; |
1415 | struct fc_frame_header *fh; |
1416 | struct fc_seq *sp; |
1417 | |
1418 | if (!ep) |
1419 | goto reject; |
1420 | |
1421 | FC_EXCH_DBG(ep, "exch: ABTS received\n" ); |
1422 | fp = fc_frame_alloc(dev: ep->lp, len: sizeof(*ap)); |
1423 | if (!fp) { |
1424 | FC_EXCH_DBG(ep, "Drop ABTS request, out of memory\n" ); |
1425 | goto free; |
1426 | } |
1427 | |
1428 | spin_lock_bh(lock: &ep->ex_lock); |
1429 | if (ep->esb_stat & ESB_ST_COMPLETE) { |
1430 | spin_unlock_bh(lock: &ep->ex_lock); |
1431 | FC_EXCH_DBG(ep, "exch: ABTS rejected, exchange complete\n" ); |
1432 | fc_frame_free(fp); |
1433 | goto reject; |
1434 | } |
1435 | if (!(ep->esb_stat & ESB_ST_REC_QUAL)) { |
1436 | ep->esb_stat |= ESB_ST_REC_QUAL; |
1437 | fc_exch_hold(ep); /* hold for REC_QUAL */ |
1438 | } |
1439 | fc_exch_timer_set_locked(ep, timer_msec: ep->r_a_tov); |
1440 | fh = fc_frame_header_get(fp); |
1441 | ap = fc_frame_payload_get(fp, len: sizeof(*ap)); |
1442 | memset(ap, 0, sizeof(*ap)); |
1443 | sp = &ep->seq; |
1444 | ap->ba_high_seq_cnt = htons(0xffff); |
1445 | if (sp->ssb_stat & SSB_ST_RESP) { |
1446 | ap->ba_seq_id = sp->id; |
1447 | ap->ba_seq_id_val = FC_BA_SEQ_ID_VAL; |
1448 | ap->ba_high_seq_cnt = fh->fh_seq_cnt; |
1449 | ap->ba_low_seq_cnt = htons(sp->cnt); |
1450 | } |
1451 | sp = fc_seq_start_next_locked(sp); |
1452 | fc_seq_send_last(sp, fp, rctl: FC_RCTL_BA_ACC, fh_type: FC_TYPE_BLS); |
1453 | ep->esb_stat |= ESB_ST_ABNORMAL; |
1454 | spin_unlock_bh(lock: &ep->ex_lock); |
1455 | |
1456 | free: |
1457 | fc_frame_free(fp: rx_fp); |
1458 | return; |
1459 | |
1460 | reject: |
1461 | fc_exch_send_ba_rjt(rx_fp, reason: FC_BA_RJT_UNABLE, explan: FC_BA_RJT_INV_XID); |
1462 | goto free; |
1463 | } |
1464 | |
1465 | /** |
1466 | * fc_seq_assign() - Assign exchange and sequence for incoming request |
1467 | * @lport: The local port that received the request |
1468 | * @fp: The request frame |
1469 | * |
1470 | * On success, the sequence pointer will be returned and also in fr_seq(@fp). |
1471 | * A reference will be held on the exchange/sequence for the caller, which |
1472 | * must call fc_seq_release(). |
1473 | */ |
1474 | struct fc_seq *fc_seq_assign(struct fc_lport *lport, struct fc_frame *fp) |
1475 | { |
1476 | struct fc_exch_mgr_anchor *ema; |
1477 | |
1478 | WARN_ON(lport != fr_dev(fp)); |
1479 | WARN_ON(fr_seq(fp)); |
1480 | fr_seq(fp) = NULL; |
1481 | |
1482 | list_for_each_entry(ema, &lport->ema_list, ema_list) |
1483 | if ((!ema->match || ema->match(fp)) && |
1484 | fc_seq_lookup_recip(lport, mp: ema->mp, fp) == FC_RJT_NONE) |
1485 | break; |
1486 | return fr_seq(fp); |
1487 | } |
1488 | EXPORT_SYMBOL(fc_seq_assign); |
1489 | |
1490 | /** |
1491 | * fc_seq_release() - Release the hold |
1492 | * @sp: The sequence. |
1493 | */ |
1494 | void fc_seq_release(struct fc_seq *sp) |
1495 | { |
1496 | fc_exch_release(fc_seq_exch(sp)); |
1497 | } |
1498 | EXPORT_SYMBOL(fc_seq_release); |
1499 | |
1500 | /** |
1501 | * fc_exch_recv_req() - Handler for an incoming request |
1502 | * @lport: The local port that received the request |
1503 | * @mp: The EM that the exchange is on |
1504 | * @fp: The request frame |
1505 | * |
1506 | * This is used when the other end is originating the exchange |
1507 | * and the sequence. |
1508 | */ |
1509 | static void fc_exch_recv_req(struct fc_lport *lport, struct fc_exch_mgr *mp, |
1510 | struct fc_frame *fp) |
1511 | { |
1512 | struct fc_frame_header *fh = fc_frame_header_get(fp); |
1513 | struct fc_seq *sp = NULL; |
1514 | struct fc_exch *ep = NULL; |
1515 | enum fc_pf_rjt_reason reject; |
1516 | |
1517 | /* We can have the wrong fc_lport at this point with NPIV, which is a |
1518 | * problem now that we know a new exchange needs to be allocated |
1519 | */ |
1520 | lport = fc_vport_id_lookup(lport, port_id: ntoh24(p: fh->fh_d_id)); |
1521 | if (!lport) { |
1522 | fc_frame_free(fp); |
1523 | return; |
1524 | } |
1525 | fr_dev(fp) = lport; |
1526 | |
1527 | BUG_ON(fr_seq(fp)); /* XXX remove later */ |
1528 | |
1529 | /* |
1530 | * If the RX_ID is 0xffff, don't allocate an exchange. |
1531 | * The upper-level protocol may request one later, if needed. |
1532 | */ |
1533 | if (fh->fh_rx_id == htons(FC_XID_UNKNOWN)) |
1534 | return fc_lport_recv(lport, fp); |
1535 | |
1536 | reject = fc_seq_lookup_recip(lport, mp, fp); |
1537 | if (reject == FC_RJT_NONE) { |
1538 | sp = fr_seq(fp); /* sequence will be held */ |
1539 | ep = fc_seq_exch(sp); |
1540 | fc_seq_send_ack(sp, rx_fp: fp); |
1541 | ep->encaps = fr_encaps(fp); |
1542 | |
1543 | /* |
1544 | * Call the receive function. |
1545 | * |
1546 | * The receive function may allocate a new sequence |
1547 | * over the old one, so we shouldn't change the |
1548 | * sequence after this. |
1549 | * |
1550 | * The frame will be freed by the receive function. |
1551 | * If new exch resp handler is valid then call that |
1552 | * first. |
1553 | */ |
1554 | if (!fc_invoke_resp(ep, sp, fp)) |
1555 | fc_lport_recv(lport, fp); |
1556 | fc_exch_release(ep); /* release from lookup */ |
1557 | } else { |
1558 | FC_LPORT_DBG(lport, "exch/seq lookup failed: reject %x\n" , |
1559 | reject); |
1560 | fc_frame_free(fp); |
1561 | } |
1562 | } |
1563 | |
1564 | /** |
1565 | * fc_exch_recv_seq_resp() - Handler for an incoming response where the other |
1566 | * end is the originator of the sequence that is a |
1567 | * response to our initial exchange |
1568 | * @mp: The EM that the exchange is on |
1569 | * @fp: The response frame |
1570 | */ |
1571 | static void fc_exch_recv_seq_resp(struct fc_exch_mgr *mp, struct fc_frame *fp) |
1572 | { |
1573 | struct fc_frame_header *fh = fc_frame_header_get(fp); |
1574 | struct fc_seq *sp; |
1575 | struct fc_exch *ep; |
1576 | enum fc_sof sof; |
1577 | u32 f_ctl; |
1578 | int rc; |
1579 | |
1580 | ep = fc_exch_find(mp, ntohs(fh->fh_ox_id)); |
1581 | if (!ep) { |
1582 | atomic_inc(v: &mp->stats.xid_not_found); |
1583 | goto out; |
1584 | } |
1585 | if (ep->esb_stat & ESB_ST_COMPLETE) { |
1586 | atomic_inc(v: &mp->stats.xid_not_found); |
1587 | goto rel; |
1588 | } |
1589 | if (ep->rxid == FC_XID_UNKNOWN) |
1590 | ep->rxid = ntohs(fh->fh_rx_id); |
1591 | if (ep->sid != 0 && ep->sid != ntoh24(p: fh->fh_d_id)) { |
1592 | atomic_inc(v: &mp->stats.xid_not_found); |
1593 | goto rel; |
1594 | } |
1595 | if (ep->did != ntoh24(p: fh->fh_s_id) && |
1596 | ep->did != FC_FID_FLOGI) { |
1597 | atomic_inc(v: &mp->stats.xid_not_found); |
1598 | goto rel; |
1599 | } |
1600 | sof = fr_sof(fp); |
1601 | sp = &ep->seq; |
1602 | if (fc_sof_is_init(sof)) { |
1603 | sp->ssb_stat |= SSB_ST_RESP; |
1604 | sp->id = fh->fh_seq_id; |
1605 | } |
1606 | |
1607 | f_ctl = ntoh24(p: fh->fh_f_ctl); |
1608 | fr_seq(fp) = sp; |
1609 | |
1610 | spin_lock_bh(lock: &ep->ex_lock); |
1611 | if (f_ctl & FC_FC_SEQ_INIT) |
1612 | ep->esb_stat |= ESB_ST_SEQ_INIT; |
1613 | spin_unlock_bh(lock: &ep->ex_lock); |
1614 | |
1615 | if (fc_sof_needs_ack(sof)) |
1616 | fc_seq_send_ack(sp, rx_fp: fp); |
1617 | |
1618 | if (fh->fh_type != FC_TYPE_FCP && fr_eof(fp) == FC_EOF_T && |
1619 | (f_ctl & (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) == |
1620 | (FC_FC_LAST_SEQ | FC_FC_END_SEQ)) { |
1621 | spin_lock_bh(lock: &ep->ex_lock); |
1622 | rc = fc_exch_done_locked(ep); |
1623 | WARN_ON(fc_seq_exch(sp) != ep); |
1624 | spin_unlock_bh(lock: &ep->ex_lock); |
1625 | if (!rc) { |
1626 | fc_exch_delete(ep); |
1627 | } else { |
1628 | FC_EXCH_DBG(ep, "ep is completed already," |
1629 | "hence skip calling the resp\n" ); |
1630 | goto skip_resp; |
1631 | } |
1632 | } |
1633 | |
1634 | /* |
1635 | * Call the receive function. |
1636 | * The sequence is held (has a refcnt) for us, |
1637 | * but not for the receive function. |
1638 | * |
1639 | * The receive function may allocate a new sequence |
1640 | * over the old one, so we shouldn't change the |
1641 | * sequence after this. |
1642 | * |
1643 | * The frame will be freed by the receive function. |
1644 | * If new exch resp handler is valid then call that |
1645 | * first. |
1646 | */ |
1647 | if (!fc_invoke_resp(ep, sp, fp)) |
1648 | fc_frame_free(fp); |
1649 | |
1650 | skip_resp: |
1651 | fc_exch_release(ep); |
1652 | return; |
1653 | rel: |
1654 | fc_exch_release(ep); |
1655 | out: |
1656 | fc_frame_free(fp); |
1657 | } |
1658 | |
1659 | /** |
1660 | * fc_exch_recv_resp() - Handler for a sequence where other end is |
1661 | * responding to our sequence |
1662 | * @mp: The EM that the exchange is on |
1663 | * @fp: The response frame |
1664 | */ |
1665 | static void fc_exch_recv_resp(struct fc_exch_mgr *mp, struct fc_frame *fp) |
1666 | { |
1667 | struct fc_seq *sp; |
1668 | |
1669 | sp = fc_seq_lookup_orig(mp, fp); /* doesn't hold sequence */ |
1670 | |
1671 | if (!sp) |
1672 | atomic_inc(v: &mp->stats.xid_not_found); |
1673 | else |
1674 | atomic_inc(v: &mp->stats.non_bls_resp); |
1675 | |
1676 | fc_frame_free(fp); |
1677 | } |
1678 | |
1679 | /** |
1680 | * fc_exch_abts_resp() - Handler for a response to an ABT |
1681 | * @ep: The exchange that the frame is on |
1682 | * @fp: The response frame |
1683 | * |
1684 | * This response would be to an ABTS cancelling an exchange or sequence. |
1685 | * The response can be either BA_ACC or BA_RJT |
1686 | */ |
1687 | static void fc_exch_abts_resp(struct fc_exch *ep, struct fc_frame *fp) |
1688 | { |
1689 | struct fc_frame_header *fh; |
1690 | struct fc_ba_acc *ap; |
1691 | struct fc_seq *sp; |
1692 | u16 low; |
1693 | u16 high; |
1694 | int rc = 1, has_rec = 0; |
1695 | |
1696 | fh = fc_frame_header_get(fp); |
1697 | FC_EXCH_DBG(ep, "exch: BLS rctl %x - %s\n" , fh->fh_r_ctl, |
1698 | fc_exch_rctl_name(fh->fh_r_ctl)); |
1699 | |
1700 | if (cancel_delayed_work_sync(dwork: &ep->timeout_work)) { |
1701 | FC_EXCH_DBG(ep, "Exchange timer canceled due to ABTS response\n" ); |
1702 | fc_exch_release(ep); /* release from pending timer hold */ |
1703 | return; |
1704 | } |
1705 | |
1706 | spin_lock_bh(lock: &ep->ex_lock); |
1707 | switch (fh->fh_r_ctl) { |
1708 | case FC_RCTL_BA_ACC: |
1709 | ap = fc_frame_payload_get(fp, len: sizeof(*ap)); |
1710 | if (!ap) |
1711 | break; |
1712 | |
1713 | /* |
1714 | * Decide whether to establish a Recovery Qualifier. |
1715 | * We do this if there is a non-empty SEQ_CNT range and |
1716 | * SEQ_ID is the same as the one we aborted. |
1717 | */ |
1718 | low = ntohs(ap->ba_low_seq_cnt); |
1719 | high = ntohs(ap->ba_high_seq_cnt); |
1720 | if ((ep->esb_stat & ESB_ST_REC_QUAL) == 0 && |
1721 | (ap->ba_seq_id_val != FC_BA_SEQ_ID_VAL || |
1722 | ap->ba_seq_id == ep->seq_id) && low != high) { |
1723 | ep->esb_stat |= ESB_ST_REC_QUAL; |
1724 | fc_exch_hold(ep); /* hold for recovery qualifier */ |
1725 | has_rec = 1; |
1726 | } |
1727 | break; |
1728 | case FC_RCTL_BA_RJT: |
1729 | break; |
1730 | default: |
1731 | break; |
1732 | } |
1733 | |
1734 | /* do we need to do some other checks here. Can we reuse more of |
1735 | * fc_exch_recv_seq_resp |
1736 | */ |
1737 | sp = &ep->seq; |
1738 | /* |
1739 | * do we want to check END_SEQ as well as LAST_SEQ here? |
1740 | */ |
1741 | if (ep->fh_type != FC_TYPE_FCP && |
1742 | ntoh24(p: fh->fh_f_ctl) & FC_FC_LAST_SEQ) |
1743 | rc = fc_exch_done_locked(ep); |
1744 | spin_unlock_bh(lock: &ep->ex_lock); |
1745 | |
1746 | fc_exch_hold(ep); |
1747 | if (!rc) |
1748 | fc_exch_delete(ep); |
1749 | if (!fc_invoke_resp(ep, sp, fp)) |
1750 | fc_frame_free(fp); |
1751 | if (has_rec) |
1752 | fc_exch_timer_set(ep, timer_msec: ep->r_a_tov); |
1753 | fc_exch_release(ep); |
1754 | } |
1755 | |
1756 | /** |
1757 | * fc_exch_recv_bls() - Handler for a BLS sequence |
1758 | * @mp: The EM that the exchange is on |
1759 | * @fp: The request frame |
1760 | * |
1761 | * The BLS frame is always a sequence initiated by the remote side. |
1762 | * We may be either the originator or recipient of the exchange. |
1763 | */ |
1764 | static void fc_exch_recv_bls(struct fc_exch_mgr *mp, struct fc_frame *fp) |
1765 | { |
1766 | struct fc_frame_header *fh; |
1767 | struct fc_exch *ep; |
1768 | u32 f_ctl; |
1769 | |
1770 | fh = fc_frame_header_get(fp); |
1771 | f_ctl = ntoh24(p: fh->fh_f_ctl); |
1772 | fr_seq(fp) = NULL; |
1773 | |
1774 | ep = fc_exch_find(mp, xid: (f_ctl & FC_FC_EX_CTX) ? |
1775 | ntohs(fh->fh_ox_id) : ntohs(fh->fh_rx_id)); |
1776 | if (ep && (f_ctl & FC_FC_SEQ_INIT)) { |
1777 | spin_lock_bh(lock: &ep->ex_lock); |
1778 | ep->esb_stat |= ESB_ST_SEQ_INIT; |
1779 | spin_unlock_bh(lock: &ep->ex_lock); |
1780 | } |
1781 | if (f_ctl & FC_FC_SEQ_CTX) { |
1782 | /* |
1783 | * A response to a sequence we initiated. |
1784 | * This should only be ACKs for class 2 or F. |
1785 | */ |
1786 | switch (fh->fh_r_ctl) { |
1787 | case FC_RCTL_ACK_1: |
1788 | case FC_RCTL_ACK_0: |
1789 | break; |
1790 | default: |
1791 | if (ep) |
1792 | FC_EXCH_DBG(ep, "BLS rctl %x - %s received\n" , |
1793 | fh->fh_r_ctl, |
1794 | fc_exch_rctl_name(fh->fh_r_ctl)); |
1795 | break; |
1796 | } |
1797 | fc_frame_free(fp); |
1798 | } else { |
1799 | switch (fh->fh_r_ctl) { |
1800 | case FC_RCTL_BA_RJT: |
1801 | case FC_RCTL_BA_ACC: |
1802 | if (ep) |
1803 | fc_exch_abts_resp(ep, fp); |
1804 | else |
1805 | fc_frame_free(fp); |
1806 | break; |
1807 | case FC_RCTL_BA_ABTS: |
1808 | if (ep) |
1809 | fc_exch_recv_abts(ep, rx_fp: fp); |
1810 | else |
1811 | fc_frame_free(fp); |
1812 | break; |
1813 | default: /* ignore junk */ |
1814 | fc_frame_free(fp); |
1815 | break; |
1816 | } |
1817 | } |
1818 | if (ep) |
1819 | fc_exch_release(ep); /* release hold taken by fc_exch_find */ |
1820 | } |
1821 | |
1822 | /** |
1823 | * fc_seq_ls_acc() - Accept sequence with LS_ACC |
1824 | * @rx_fp: The received frame, not freed here. |
1825 | * |
1826 | * If this fails due to allocation or transmit congestion, assume the |
1827 | * originator will repeat the sequence. |
1828 | */ |
1829 | static void fc_seq_ls_acc(struct fc_frame *rx_fp) |
1830 | { |
1831 | struct fc_lport *lport; |
1832 | struct fc_els_ls_acc *acc; |
1833 | struct fc_frame *fp; |
1834 | struct fc_seq *sp; |
1835 | |
1836 | lport = fr_dev(rx_fp); |
1837 | sp = fr_seq(rx_fp); |
1838 | fp = fc_frame_alloc(dev: lport, len: sizeof(*acc)); |
1839 | if (!fp) { |
1840 | FC_EXCH_DBG(fc_seq_exch(sp), |
1841 | "exch: drop LS_ACC, out of memory\n" ); |
1842 | return; |
1843 | } |
1844 | acc = fc_frame_payload_get(fp, len: sizeof(*acc)); |
1845 | memset(acc, 0, sizeof(*acc)); |
1846 | acc->la_cmd = ELS_LS_ACC; |
1847 | fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, parm_offset: 0); |
1848 | lport->tt.frame_send(lport, fp); |
1849 | } |
1850 | |
1851 | /** |
1852 | * fc_seq_ls_rjt() - Reject a sequence with ELS LS_RJT |
1853 | * @rx_fp: The received frame, not freed here. |
1854 | * @reason: The reason the sequence is being rejected |
1855 | * @explan: The explanation for the rejection |
1856 | * |
1857 | * If this fails due to allocation or transmit congestion, assume the |
1858 | * originator will repeat the sequence. |
1859 | */ |
1860 | static void fc_seq_ls_rjt(struct fc_frame *rx_fp, enum fc_els_rjt_reason reason, |
1861 | enum fc_els_rjt_explan explan) |
1862 | { |
1863 | struct fc_lport *lport; |
1864 | struct fc_els_ls_rjt *rjt; |
1865 | struct fc_frame *fp; |
1866 | struct fc_seq *sp; |
1867 | |
1868 | lport = fr_dev(rx_fp); |
1869 | sp = fr_seq(rx_fp); |
1870 | fp = fc_frame_alloc(dev: lport, len: sizeof(*rjt)); |
1871 | if (!fp) { |
1872 | FC_EXCH_DBG(fc_seq_exch(sp), |
1873 | "exch: drop LS_ACC, out of memory\n" ); |
1874 | return; |
1875 | } |
1876 | rjt = fc_frame_payload_get(fp, len: sizeof(*rjt)); |
1877 | memset(rjt, 0, sizeof(*rjt)); |
1878 | rjt->er_cmd = ELS_LS_RJT; |
1879 | rjt->er_reason = reason; |
1880 | rjt->er_explan = explan; |
1881 | fc_fill_reply_hdr(fp, rx_fp, FC_RCTL_ELS_REP, parm_offset: 0); |
1882 | lport->tt.frame_send(lport, fp); |
1883 | } |
1884 | |
1885 | /** |
1886 | * fc_exch_reset() - Reset an exchange |
1887 | * @ep: The exchange to be reset |
1888 | * |
1889 | * Note: May sleep if invoked from outside a response handler. |
1890 | */ |
1891 | static void fc_exch_reset(struct fc_exch *ep) |
1892 | { |
1893 | struct fc_seq *sp; |
1894 | int rc = 1; |
1895 | |
1896 | spin_lock_bh(lock: &ep->ex_lock); |
1897 | ep->state |= FC_EX_RST_CLEANUP; |
1898 | fc_exch_timer_cancel(ep); |
1899 | if (ep->esb_stat & ESB_ST_REC_QUAL) |
1900 | atomic_dec(v: &ep->ex_refcnt); /* drop hold for rec_qual */ |
1901 | ep->esb_stat &= ~ESB_ST_REC_QUAL; |
1902 | sp = &ep->seq; |
1903 | rc = fc_exch_done_locked(ep); |
1904 | spin_unlock_bh(lock: &ep->ex_lock); |
1905 | |
1906 | fc_exch_hold(ep); |
1907 | |
1908 | if (!rc) { |
1909 | fc_exch_delete(ep); |
1910 | } else { |
1911 | FC_EXCH_DBG(ep, "ep is completed already," |
1912 | "hence skip calling the resp\n" ); |
1913 | goto skip_resp; |
1914 | } |
1915 | |
1916 | fc_invoke_resp(ep, sp, fp: ERR_PTR(error: -FC_EX_CLOSED)); |
1917 | skip_resp: |
1918 | fc_seq_set_resp(sp, NULL, ep->arg); |
1919 | fc_exch_release(ep); |
1920 | } |
1921 | |
1922 | /** |
1923 | * fc_exch_pool_reset() - Reset a per cpu exchange pool |
1924 | * @lport: The local port that the exchange pool is on |
1925 | * @pool: The exchange pool to be reset |
1926 | * @sid: The source ID |
1927 | * @did: The destination ID |
1928 | * |
1929 | * Resets a per cpu exches pool, releasing all of its sequences |
1930 | * and exchanges. If sid is non-zero then reset only exchanges |
1931 | * we sourced from the local port's FID. If did is non-zero then |
1932 | * only reset exchanges destined for the local port's FID. |
1933 | */ |
1934 | static void fc_exch_pool_reset(struct fc_lport *lport, |
1935 | struct fc_exch_pool *pool, |
1936 | u32 sid, u32 did) |
1937 | { |
1938 | struct fc_exch *ep; |
1939 | struct fc_exch *next; |
1940 | |
1941 | spin_lock_bh(lock: &pool->lock); |
1942 | restart: |
1943 | list_for_each_entry_safe(ep, next, &pool->ex_list, ex_list) { |
1944 | if ((lport == ep->lp) && |
1945 | (sid == 0 || sid == ep->sid) && |
1946 | (did == 0 || did == ep->did)) { |
1947 | fc_exch_hold(ep); |
1948 | spin_unlock_bh(lock: &pool->lock); |
1949 | |
1950 | fc_exch_reset(ep); |
1951 | |
1952 | fc_exch_release(ep); |
1953 | spin_lock_bh(lock: &pool->lock); |
1954 | |
1955 | /* |
1956 | * must restart loop incase while lock |
1957 | * was down multiple eps were released. |
1958 | */ |
1959 | goto restart; |
1960 | } |
1961 | } |
1962 | pool->next_index = 0; |
1963 | pool->left = FC_XID_UNKNOWN; |
1964 | pool->right = FC_XID_UNKNOWN; |
1965 | spin_unlock_bh(lock: &pool->lock); |
1966 | } |
1967 | |
1968 | /** |
1969 | * fc_exch_mgr_reset() - Reset all EMs of a local port |
1970 | * @lport: The local port whose EMs are to be reset |
1971 | * @sid: The source ID |
1972 | * @did: The destination ID |
1973 | * |
1974 | * Reset all EMs associated with a given local port. Release all |
1975 | * sequences and exchanges. If sid is non-zero then reset only the |
1976 | * exchanges sent from the local port's FID. If did is non-zero then |
1977 | * reset only exchanges destined for the local port's FID. |
1978 | */ |
1979 | void fc_exch_mgr_reset(struct fc_lport *lport, u32 sid, u32 did) |
1980 | { |
1981 | struct fc_exch_mgr_anchor *ema; |
1982 | unsigned int cpu; |
1983 | |
1984 | list_for_each_entry(ema, &lport->ema_list, ema_list) { |
1985 | for_each_possible_cpu(cpu) |
1986 | fc_exch_pool_reset(lport, |
1987 | per_cpu_ptr(ema->mp->pool, cpu), |
1988 | sid, did); |
1989 | } |
1990 | } |
1991 | EXPORT_SYMBOL(fc_exch_mgr_reset); |
1992 | |
1993 | /** |
1994 | * fc_exch_lookup() - find an exchange |
1995 | * @lport: The local port |
1996 | * @xid: The exchange ID |
1997 | * |
1998 | * Returns exchange pointer with hold for caller, or NULL if not found. |
1999 | */ |
2000 | static struct fc_exch *fc_exch_lookup(struct fc_lport *lport, u32 xid) |
2001 | { |
2002 | struct fc_exch_mgr_anchor *ema; |
2003 | |
2004 | list_for_each_entry(ema, &lport->ema_list, ema_list) |
2005 | if (ema->mp->min_xid <= xid && xid <= ema->mp->max_xid) |
2006 | return fc_exch_find(mp: ema->mp, xid); |
2007 | return NULL; |
2008 | } |
2009 | |
2010 | /** |
2011 | * fc_exch_els_rec() - Handler for ELS REC (Read Exchange Concise) requests |
2012 | * @rfp: The REC frame, not freed here. |
2013 | * |
2014 | * Note that the requesting port may be different than the S_ID in the request. |
2015 | */ |
2016 | static void fc_exch_els_rec(struct fc_frame *rfp) |
2017 | { |
2018 | struct fc_lport *lport; |
2019 | struct fc_frame *fp; |
2020 | struct fc_exch *ep; |
2021 | struct fc_els_rec *rp; |
2022 | struct fc_els_rec_acc *acc; |
2023 | enum fc_els_rjt_reason reason = ELS_RJT_LOGIC; |
2024 | enum fc_els_rjt_explan explan; |
2025 | u32 sid; |
2026 | u16 xid, rxid, oxid; |
2027 | |
2028 | lport = fr_dev(rfp); |
2029 | rp = fc_frame_payload_get(fp: rfp, len: sizeof(*rp)); |
2030 | explan = ELS_EXPL_INV_LEN; |
2031 | if (!rp) |
2032 | goto reject; |
2033 | sid = ntoh24(p: rp->rec_s_id); |
2034 | rxid = ntohs(rp->rec_rx_id); |
2035 | oxid = ntohs(rp->rec_ox_id); |
2036 | |
2037 | explan = ELS_EXPL_OXID_RXID; |
2038 | if (sid == fc_host_port_id(lport->host)) |
2039 | xid = oxid; |
2040 | else |
2041 | xid = rxid; |
2042 | if (xid == FC_XID_UNKNOWN) { |
2043 | FC_LPORT_DBG(lport, |
2044 | "REC request from %x: invalid rxid %x oxid %x\n" , |
2045 | sid, rxid, oxid); |
2046 | goto reject; |
2047 | } |
2048 | ep = fc_exch_lookup(lport, xid); |
2049 | if (!ep) { |
2050 | FC_LPORT_DBG(lport, |
2051 | "REC request from %x: rxid %x oxid %x not found\n" , |
2052 | sid, rxid, oxid); |
2053 | goto reject; |
2054 | } |
2055 | FC_EXCH_DBG(ep, "REC request from %x: rxid %x oxid %x\n" , |
2056 | sid, rxid, oxid); |
2057 | if (ep->oid != sid || oxid != ep->oxid) |
2058 | goto rel; |
2059 | if (rxid != FC_XID_UNKNOWN && rxid != ep->rxid) |
2060 | goto rel; |
2061 | fp = fc_frame_alloc(dev: lport, len: sizeof(*acc)); |
2062 | if (!fp) { |
2063 | FC_EXCH_DBG(ep, "Drop REC request, out of memory\n" ); |
2064 | goto out; |
2065 | } |
2066 | |
2067 | acc = fc_frame_payload_get(fp, len: sizeof(*acc)); |
2068 | memset(acc, 0, sizeof(*acc)); |
2069 | acc->reca_cmd = ELS_LS_ACC; |
2070 | acc->reca_ox_id = rp->rec_ox_id; |
2071 | memcpy(acc->reca_ofid, rp->rec_s_id, 3); |
2072 | acc->reca_rx_id = htons(ep->rxid); |
2073 | if (ep->sid == ep->oid) |
2074 | hton24(p: acc->reca_rfid, v: ep->did); |
2075 | else |
2076 | hton24(p: acc->reca_rfid, v: ep->sid); |
2077 | acc->reca_fc4value = htonl(ep->seq.rec_data); |
2078 | acc->reca_e_stat = htonl(ep->esb_stat & (ESB_ST_RESP | |
2079 | ESB_ST_SEQ_INIT | |
2080 | ESB_ST_COMPLETE)); |
2081 | fc_fill_reply_hdr(fp, rfp, FC_RCTL_ELS_REP, parm_offset: 0); |
2082 | lport->tt.frame_send(lport, fp); |
2083 | out: |
2084 | fc_exch_release(ep); |
2085 | return; |
2086 | |
2087 | rel: |
2088 | fc_exch_release(ep); |
2089 | reject: |
2090 | fc_seq_ls_rjt(rx_fp: rfp, reason, explan); |
2091 | } |
2092 | |
2093 | /** |
2094 | * fc_exch_rrq_resp() - Handler for RRQ responses |
2095 | * @sp: The sequence that the RRQ is on |
2096 | * @fp: The RRQ frame |
2097 | * @arg: The exchange that the RRQ is on |
2098 | * |
2099 | * TODO: fix error handler. |
2100 | */ |
2101 | static void fc_exch_rrq_resp(struct fc_seq *sp, struct fc_frame *fp, void *arg) |
2102 | { |
2103 | struct fc_exch *aborted_ep = arg; |
2104 | unsigned int op; |
2105 | |
2106 | if (IS_ERR(ptr: fp)) { |
2107 | int err = PTR_ERR(ptr: fp); |
2108 | |
2109 | if (err == -FC_EX_CLOSED || err == -FC_EX_TIMEOUT) |
2110 | goto cleanup; |
2111 | FC_EXCH_DBG(aborted_ep, "Cannot process RRQ, " |
2112 | "frame error %d\n" , err); |
2113 | return; |
2114 | } |
2115 | |
2116 | op = fc_frame_payload_op(fp); |
2117 | fc_frame_free(fp); |
2118 | |
2119 | switch (op) { |
2120 | case ELS_LS_RJT: |
2121 | FC_EXCH_DBG(aborted_ep, "LS_RJT for RRQ\n" ); |
2122 | fallthrough; |
2123 | case ELS_LS_ACC: |
2124 | goto cleanup; |
2125 | default: |
2126 | FC_EXCH_DBG(aborted_ep, "unexpected response op %x for RRQ\n" , |
2127 | op); |
2128 | return; |
2129 | } |
2130 | |
2131 | cleanup: |
2132 | fc_exch_done(&aborted_ep->seq); |
2133 | /* drop hold for rec qual */ |
2134 | fc_exch_release(ep: aborted_ep); |
2135 | } |
2136 | |
2137 | |
2138 | /** |
2139 | * fc_exch_seq_send() - Send a frame using a new exchange and sequence |
2140 | * @lport: The local port to send the frame on |
2141 | * @fp: The frame to be sent |
2142 | * @resp: The response handler for this request |
2143 | * @destructor: The destructor for the exchange |
2144 | * @arg: The argument to be passed to the response handler |
2145 | * @timer_msec: The timeout period for the exchange |
2146 | * |
2147 | * The exchange response handler is set in this routine to resp() |
2148 | * function pointer. It can be called in two scenarios: if a timeout |
2149 | * occurs or if a response frame is received for the exchange. The |
2150 | * fc_frame pointer in response handler will also indicate timeout |
2151 | * as error using IS_ERR related macros. |
2152 | * |
2153 | * The exchange destructor handler is also set in this routine. |
2154 | * The destructor handler is invoked by EM layer when exchange |
2155 | * is about to free, this can be used by caller to free its |
2156 | * resources along with exchange free. |
2157 | * |
2158 | * The arg is passed back to resp and destructor handler. |
2159 | * |
2160 | * The timeout value (in msec) for an exchange is set if non zero |
2161 | * timer_msec argument is specified. The timer is canceled when |
2162 | * it fires or when the exchange is done. The exchange timeout handler |
2163 | * is registered by EM layer. |
2164 | * |
2165 | * The frame pointer with some of the header's fields must be |
2166 | * filled before calling this routine, those fields are: |
2167 | * |
2168 | * - routing control |
2169 | * - FC port did |
2170 | * - FC port sid |
2171 | * - FC header type |
2172 | * - frame control |
2173 | * - parameter or relative offset |
2174 | */ |
2175 | struct fc_seq *fc_exch_seq_send(struct fc_lport *lport, |
2176 | struct fc_frame *fp, |
2177 | void (*resp)(struct fc_seq *, |
2178 | struct fc_frame *fp, |
2179 | void *arg), |
2180 | void (*destructor)(struct fc_seq *, void *), |
2181 | void *arg, u32 timer_msec) |
2182 | { |
2183 | struct fc_exch *ep; |
2184 | struct fc_seq *sp = NULL; |
2185 | struct fc_frame_header *fh; |
2186 | struct fc_fcp_pkt *fsp = NULL; |
2187 | int rc = 1; |
2188 | |
2189 | ep = fc_exch_alloc(lport, fp); |
2190 | if (!ep) { |
2191 | fc_frame_free(fp); |
2192 | return NULL; |
2193 | } |
2194 | ep->esb_stat |= ESB_ST_SEQ_INIT; |
2195 | fh = fc_frame_header_get(fp); |
2196 | fc_exch_set_addr(ep, orig_id: ntoh24(p: fh->fh_s_id), resp_id: ntoh24(p: fh->fh_d_id)); |
2197 | ep->resp = resp; |
2198 | ep->destructor = destructor; |
2199 | ep->arg = arg; |
2200 | ep->r_a_tov = lport->r_a_tov; |
2201 | ep->lp = lport; |
2202 | sp = &ep->seq; |
2203 | |
2204 | ep->fh_type = fh->fh_type; /* save for possbile timeout handling */ |
2205 | ep->f_ctl = ntoh24(p: fh->fh_f_ctl); |
2206 | fc_exch_setup_hdr(ep, fp, f_ctl: ep->f_ctl); |
2207 | sp->cnt++; |
2208 | |
2209 | if (ep->xid <= lport->lro_xid && fh->fh_r_ctl == FC_RCTL_DD_UNSOL_CMD) { |
2210 | fsp = fr_fsp(fp); |
2211 | fc_fcp_ddp_setup(fr_fsp(fp), xid: ep->xid); |
2212 | } |
2213 | |
2214 | if (unlikely(lport->tt.frame_send(lport, fp))) |
2215 | goto err; |
2216 | |
2217 | if (timer_msec) |
2218 | fc_exch_timer_set_locked(ep, timer_msec); |
2219 | ep->f_ctl &= ~FC_FC_FIRST_SEQ; /* not first seq */ |
2220 | |
2221 | if (ep->f_ctl & FC_FC_SEQ_INIT) |
2222 | ep->esb_stat &= ~ESB_ST_SEQ_INIT; |
2223 | spin_unlock_bh(lock: &ep->ex_lock); |
2224 | return sp; |
2225 | err: |
2226 | if (fsp) |
2227 | fc_fcp_ddp_done(fsp); |
2228 | rc = fc_exch_done_locked(ep); |
2229 | spin_unlock_bh(lock: &ep->ex_lock); |
2230 | if (!rc) |
2231 | fc_exch_delete(ep); |
2232 | return NULL; |
2233 | } |
2234 | EXPORT_SYMBOL(fc_exch_seq_send); |
2235 | |
2236 | /** |
2237 | * fc_exch_rrq() - Send an ELS RRQ (Reinstate Recovery Qualifier) command |
2238 | * @ep: The exchange to send the RRQ on |
2239 | * |
2240 | * This tells the remote port to stop blocking the use of |
2241 | * the exchange and the seq_cnt range. |
2242 | */ |
2243 | static void fc_exch_rrq(struct fc_exch *ep) |
2244 | { |
2245 | struct fc_lport *lport; |
2246 | struct fc_els_rrq *rrq; |
2247 | struct fc_frame *fp; |
2248 | u32 did; |
2249 | |
2250 | lport = ep->lp; |
2251 | |
2252 | fp = fc_frame_alloc(dev: lport, len: sizeof(*rrq)); |
2253 | if (!fp) |
2254 | goto retry; |
2255 | |
2256 | rrq = fc_frame_payload_get(fp, len: sizeof(*rrq)); |
2257 | memset(rrq, 0, sizeof(*rrq)); |
2258 | rrq->rrq_cmd = ELS_RRQ; |
2259 | hton24(p: rrq->rrq_s_id, v: ep->sid); |
2260 | rrq->rrq_ox_id = htons(ep->oxid); |
2261 | rrq->rrq_rx_id = htons(ep->rxid); |
2262 | |
2263 | did = ep->did; |
2264 | if (ep->esb_stat & ESB_ST_RESP) |
2265 | did = ep->sid; |
2266 | |
2267 | fc_fill_fc_hdr(fp, r_ctl: FC_RCTL_ELS_REQ, did, |
2268 | sid: lport->port_id, type: FC_TYPE_ELS, |
2269 | FC_FC_FIRST_SEQ | FC_FC_END_SEQ | FC_FC_SEQ_INIT, parm_offset: 0); |
2270 | |
2271 | if (fc_exch_seq_send(lport, fp, fc_exch_rrq_resp, NULL, ep, |
2272 | lport->e_d_tov)) |
2273 | return; |
2274 | |
2275 | retry: |
2276 | FC_EXCH_DBG(ep, "exch: RRQ send failed\n" ); |
2277 | spin_lock_bh(lock: &ep->ex_lock); |
2278 | if (ep->state & (FC_EX_RST_CLEANUP | FC_EX_DONE)) { |
2279 | spin_unlock_bh(lock: &ep->ex_lock); |
2280 | /* drop hold for rec qual */ |
2281 | fc_exch_release(ep); |
2282 | return; |
2283 | } |
2284 | ep->esb_stat |= ESB_ST_REC_QUAL; |
2285 | fc_exch_timer_set_locked(ep, timer_msec: ep->r_a_tov); |
2286 | spin_unlock_bh(lock: &ep->ex_lock); |
2287 | } |
2288 | |
2289 | /** |
2290 | * fc_exch_els_rrq() - Handler for ELS RRQ (Reset Recovery Qualifier) requests |
2291 | * @fp: The RRQ frame, not freed here. |
2292 | */ |
2293 | static void fc_exch_els_rrq(struct fc_frame *fp) |
2294 | { |
2295 | struct fc_lport *lport; |
2296 | struct fc_exch *ep = NULL; /* request or subject exchange */ |
2297 | struct fc_els_rrq *rp; |
2298 | u32 sid; |
2299 | u16 xid; |
2300 | enum fc_els_rjt_explan explan; |
2301 | |
2302 | lport = fr_dev(fp); |
2303 | rp = fc_frame_payload_get(fp, len: sizeof(*rp)); |
2304 | explan = ELS_EXPL_INV_LEN; |
2305 | if (!rp) |
2306 | goto reject; |
2307 | |
2308 | /* |
2309 | * lookup subject exchange. |
2310 | */ |
2311 | sid = ntoh24(p: rp->rrq_s_id); /* subject source */ |
2312 | xid = fc_host_port_id(lport->host) == sid ? |
2313 | ntohs(rp->rrq_ox_id) : ntohs(rp->rrq_rx_id); |
2314 | ep = fc_exch_lookup(lport, xid); |
2315 | explan = ELS_EXPL_OXID_RXID; |
2316 | if (!ep) |
2317 | goto reject; |
2318 | spin_lock_bh(lock: &ep->ex_lock); |
2319 | FC_EXCH_DBG(ep, "RRQ request from %x: xid %x rxid %x oxid %x\n" , |
2320 | sid, xid, ntohs(rp->rrq_rx_id), ntohs(rp->rrq_ox_id)); |
2321 | if (ep->oxid != ntohs(rp->rrq_ox_id)) |
2322 | goto unlock_reject; |
2323 | if (ep->rxid != ntohs(rp->rrq_rx_id) && |
2324 | ep->rxid != FC_XID_UNKNOWN) |
2325 | goto unlock_reject; |
2326 | explan = ELS_EXPL_SID; |
2327 | if (ep->sid != sid) |
2328 | goto unlock_reject; |
2329 | |
2330 | /* |
2331 | * Clear Recovery Qualifier state, and cancel timer if complete. |
2332 | */ |
2333 | if (ep->esb_stat & ESB_ST_REC_QUAL) { |
2334 | ep->esb_stat &= ~ESB_ST_REC_QUAL; |
2335 | atomic_dec(v: &ep->ex_refcnt); /* drop hold for rec qual */ |
2336 | } |
2337 | if (ep->esb_stat & ESB_ST_COMPLETE) |
2338 | fc_exch_timer_cancel(ep); |
2339 | |
2340 | spin_unlock_bh(lock: &ep->ex_lock); |
2341 | |
2342 | /* |
2343 | * Send LS_ACC. |
2344 | */ |
2345 | fc_seq_ls_acc(rx_fp: fp); |
2346 | goto out; |
2347 | |
2348 | unlock_reject: |
2349 | spin_unlock_bh(lock: &ep->ex_lock); |
2350 | reject: |
2351 | fc_seq_ls_rjt(rx_fp: fp, reason: ELS_RJT_LOGIC, explan); |
2352 | out: |
2353 | if (ep) |
2354 | fc_exch_release(ep); /* drop hold from fc_exch_find */ |
2355 | } |
2356 | |
2357 | /** |
2358 | * fc_exch_update_stats() - update exches stats to lport |
2359 | * @lport: The local port to update exchange manager stats |
2360 | */ |
2361 | void fc_exch_update_stats(struct fc_lport *lport) |
2362 | { |
2363 | struct fc_host_statistics *st; |
2364 | struct fc_exch_mgr_anchor *ema; |
2365 | struct fc_exch_mgr *mp; |
2366 | |
2367 | st = &lport->host_stats; |
2368 | |
2369 | list_for_each_entry(ema, &lport->ema_list, ema_list) { |
2370 | mp = ema->mp; |
2371 | st->fc_no_free_exch += atomic_read(v: &mp->stats.no_free_exch); |
2372 | st->fc_no_free_exch_xid += |
2373 | atomic_read(v: &mp->stats.no_free_exch_xid); |
2374 | st->fc_xid_not_found += atomic_read(v: &mp->stats.xid_not_found); |
2375 | st->fc_xid_busy += atomic_read(v: &mp->stats.xid_busy); |
2376 | st->fc_seq_not_found += atomic_read(v: &mp->stats.seq_not_found); |
2377 | st->fc_non_bls_resp += atomic_read(v: &mp->stats.non_bls_resp); |
2378 | } |
2379 | } |
2380 | EXPORT_SYMBOL(fc_exch_update_stats); |
2381 | |
2382 | /** |
2383 | * fc_exch_mgr_add() - Add an exchange manager to a local port's list of EMs |
2384 | * @lport: The local port to add the exchange manager to |
2385 | * @mp: The exchange manager to be added to the local port |
2386 | * @match: The match routine that indicates when this EM should be used |
2387 | */ |
2388 | struct fc_exch_mgr_anchor *fc_exch_mgr_add(struct fc_lport *lport, |
2389 | struct fc_exch_mgr *mp, |
2390 | bool (*match)(struct fc_frame *)) |
2391 | { |
2392 | struct fc_exch_mgr_anchor *ema; |
2393 | |
2394 | ema = kmalloc(size: sizeof(*ema), GFP_ATOMIC); |
2395 | if (!ema) |
2396 | return ema; |
2397 | |
2398 | ema->mp = mp; |
2399 | ema->match = match; |
2400 | /* add EM anchor to EM anchors list */ |
2401 | list_add_tail(new: &ema->ema_list, head: &lport->ema_list); |
2402 | kref_get(kref: &mp->kref); |
2403 | return ema; |
2404 | } |
2405 | EXPORT_SYMBOL(fc_exch_mgr_add); |
2406 | |
2407 | /** |
2408 | * fc_exch_mgr_destroy() - Destroy an exchange manager |
2409 | * @kref: The reference to the EM to be destroyed |
2410 | */ |
2411 | static void fc_exch_mgr_destroy(struct kref *kref) |
2412 | { |
2413 | struct fc_exch_mgr *mp = container_of(kref, struct fc_exch_mgr, kref); |
2414 | |
2415 | mempool_destroy(pool: mp->ep_pool); |
2416 | free_percpu(pdata: mp->pool); |
2417 | kfree(objp: mp); |
2418 | } |
2419 | |
2420 | /** |
2421 | * fc_exch_mgr_del() - Delete an EM from a local port's list |
2422 | * @ema: The exchange manager anchor identifying the EM to be deleted |
2423 | */ |
2424 | void fc_exch_mgr_del(struct fc_exch_mgr_anchor *ema) |
2425 | { |
2426 | /* remove EM anchor from EM anchors list */ |
2427 | list_del(entry: &ema->ema_list); |
2428 | kref_put(kref: &ema->mp->kref, release: fc_exch_mgr_destroy); |
2429 | kfree(objp: ema); |
2430 | } |
2431 | EXPORT_SYMBOL(fc_exch_mgr_del); |
2432 | |
2433 | /** |
2434 | * fc_exch_mgr_list_clone() - Share all exchange manager objects |
2435 | * @src: Source lport to clone exchange managers from |
2436 | * @dst: New lport that takes references to all the exchange managers |
2437 | */ |
2438 | int fc_exch_mgr_list_clone(struct fc_lport *src, struct fc_lport *dst) |
2439 | { |
2440 | struct fc_exch_mgr_anchor *ema, *tmp; |
2441 | |
2442 | list_for_each_entry(ema, &src->ema_list, ema_list) { |
2443 | if (!fc_exch_mgr_add(dst, ema->mp, ema->match)) |
2444 | goto err; |
2445 | } |
2446 | return 0; |
2447 | err: |
2448 | list_for_each_entry_safe(ema, tmp, &dst->ema_list, ema_list) |
2449 | fc_exch_mgr_del(ema); |
2450 | return -ENOMEM; |
2451 | } |
2452 | EXPORT_SYMBOL(fc_exch_mgr_list_clone); |
2453 | |
2454 | /** |
2455 | * fc_exch_mgr_alloc() - Allocate an exchange manager |
2456 | * @lport: The local port that the new EM will be associated with |
2457 | * @class: The default FC class for new exchanges |
2458 | * @min_xid: The minimum XID for exchanges from the new EM |
2459 | * @max_xid: The maximum XID for exchanges from the new EM |
2460 | * @match: The match routine for the new EM |
2461 | */ |
2462 | struct fc_exch_mgr *fc_exch_mgr_alloc(struct fc_lport *lport, |
2463 | enum fc_class class, |
2464 | u16 min_xid, u16 max_xid, |
2465 | bool (*match)(struct fc_frame *)) |
2466 | { |
2467 | struct fc_exch_mgr *mp; |
2468 | u16 pool_exch_range; |
2469 | size_t pool_size; |
2470 | unsigned int cpu; |
2471 | struct fc_exch_pool *pool; |
2472 | |
2473 | if (max_xid <= min_xid || max_xid == FC_XID_UNKNOWN || |
2474 | (min_xid & fc_cpu_mask) != 0) { |
2475 | FC_LPORT_DBG(lport, "Invalid min_xid 0x:%x and max_xid 0x:%x\n" , |
2476 | min_xid, max_xid); |
2477 | return NULL; |
2478 | } |
2479 | |
2480 | /* |
2481 | * allocate memory for EM |
2482 | */ |
2483 | mp = kzalloc(size: sizeof(struct fc_exch_mgr), GFP_ATOMIC); |
2484 | if (!mp) |
2485 | return NULL; |
2486 | |
2487 | mp->class = class; |
2488 | mp->lport = lport; |
2489 | /* adjust em exch xid range for offload */ |
2490 | mp->min_xid = min_xid; |
2491 | |
2492 | /* reduce range so per cpu pool fits into PCPU_MIN_UNIT_SIZE pool */ |
2493 | pool_exch_range = (PCPU_MIN_UNIT_SIZE - sizeof(*pool)) / |
2494 | sizeof(struct fc_exch *); |
2495 | if ((max_xid - min_xid + 1) / (fc_cpu_mask + 1) > pool_exch_range) { |
2496 | mp->max_xid = pool_exch_range * (fc_cpu_mask + 1) + |
2497 | min_xid - 1; |
2498 | } else { |
2499 | mp->max_xid = max_xid; |
2500 | pool_exch_range = (mp->max_xid - mp->min_xid + 1) / |
2501 | (fc_cpu_mask + 1); |
2502 | } |
2503 | |
2504 | mp->ep_pool = mempool_create_slab_pool(min_nr: 2, kc: fc_em_cachep); |
2505 | if (!mp->ep_pool) |
2506 | goto free_mp; |
2507 | |
2508 | /* |
2509 | * Setup per cpu exch pool with entire exchange id range equally |
2510 | * divided across all cpus. The exch pointers array memory is |
2511 | * allocated for exch range per pool. |
2512 | */ |
2513 | mp->pool_max_index = pool_exch_range - 1; |
2514 | |
2515 | /* |
2516 | * Allocate and initialize per cpu exch pool |
2517 | */ |
2518 | pool_size = sizeof(*pool) + pool_exch_range * sizeof(struct fc_exch *); |
2519 | mp->pool = __alloc_percpu(size: pool_size, align: __alignof__(struct fc_exch_pool)); |
2520 | if (!mp->pool) |
2521 | goto free_mempool; |
2522 | for_each_possible_cpu(cpu) { |
2523 | pool = per_cpu_ptr(mp->pool, cpu); |
2524 | pool->next_index = 0; |
2525 | pool->left = FC_XID_UNKNOWN; |
2526 | pool->right = FC_XID_UNKNOWN; |
2527 | spin_lock_init(&pool->lock); |
2528 | INIT_LIST_HEAD(list: &pool->ex_list); |
2529 | } |
2530 | |
2531 | kref_init(kref: &mp->kref); |
2532 | if (!fc_exch_mgr_add(lport, mp, match)) { |
2533 | free_percpu(pdata: mp->pool); |
2534 | goto free_mempool; |
2535 | } |
2536 | |
2537 | /* |
2538 | * Above kref_init() sets mp->kref to 1 and then |
2539 | * call to fc_exch_mgr_add incremented mp->kref again, |
2540 | * so adjust that extra increment. |
2541 | */ |
2542 | kref_put(kref: &mp->kref, release: fc_exch_mgr_destroy); |
2543 | return mp; |
2544 | |
2545 | free_mempool: |
2546 | mempool_destroy(pool: mp->ep_pool); |
2547 | free_mp: |
2548 | kfree(objp: mp); |
2549 | return NULL; |
2550 | } |
2551 | EXPORT_SYMBOL(fc_exch_mgr_alloc); |
2552 | |
2553 | /** |
2554 | * fc_exch_mgr_free() - Free all exchange managers on a local port |
2555 | * @lport: The local port whose EMs are to be freed |
2556 | */ |
2557 | void fc_exch_mgr_free(struct fc_lport *lport) |
2558 | { |
2559 | struct fc_exch_mgr_anchor *ema, *next; |
2560 | |
2561 | flush_workqueue(fc_exch_workqueue); |
2562 | list_for_each_entry_safe(ema, next, &lport->ema_list, ema_list) |
2563 | fc_exch_mgr_del(ema); |
2564 | } |
2565 | EXPORT_SYMBOL(fc_exch_mgr_free); |
2566 | |
2567 | /** |
2568 | * fc_find_ema() - Lookup and return appropriate Exchange Manager Anchor depending |
2569 | * upon 'xid'. |
2570 | * @f_ctl: f_ctl |
2571 | * @lport: The local port the frame was received on |
2572 | * @fh: The received frame header |
2573 | */ |
2574 | static struct fc_exch_mgr_anchor *fc_find_ema(u32 f_ctl, |
2575 | struct fc_lport *lport, |
2576 | struct fc_frame_header *fh) |
2577 | { |
2578 | struct fc_exch_mgr_anchor *ema; |
2579 | u16 xid; |
2580 | |
2581 | if (f_ctl & FC_FC_EX_CTX) |
2582 | xid = ntohs(fh->fh_ox_id); |
2583 | else { |
2584 | xid = ntohs(fh->fh_rx_id); |
2585 | if (xid == FC_XID_UNKNOWN) |
2586 | return list_entry(lport->ema_list.prev, |
2587 | typeof(*ema), ema_list); |
2588 | } |
2589 | |
2590 | list_for_each_entry(ema, &lport->ema_list, ema_list) { |
2591 | if ((xid >= ema->mp->min_xid) && |
2592 | (xid <= ema->mp->max_xid)) |
2593 | return ema; |
2594 | } |
2595 | return NULL; |
2596 | } |
2597 | /** |
2598 | * fc_exch_recv() - Handler for received frames |
2599 | * @lport: The local port the frame was received on |
2600 | * @fp: The received frame |
2601 | */ |
2602 | void fc_exch_recv(struct fc_lport *lport, struct fc_frame *fp) |
2603 | { |
2604 | struct fc_frame_header *fh = fc_frame_header_get(fp); |
2605 | struct fc_exch_mgr_anchor *ema; |
2606 | u32 f_ctl; |
2607 | |
2608 | /* lport lock ? */ |
2609 | if (!lport || lport->state == LPORT_ST_DISABLED) { |
2610 | FC_LIBFC_DBG("Receiving frames for an lport that " |
2611 | "has not been initialized correctly\n" ); |
2612 | fc_frame_free(fp); |
2613 | return; |
2614 | } |
2615 | |
2616 | f_ctl = ntoh24(p: fh->fh_f_ctl); |
2617 | ema = fc_find_ema(f_ctl, lport, fh); |
2618 | if (!ema) { |
2619 | FC_LPORT_DBG(lport, "Unable to find Exchange Manager Anchor," |
2620 | "fc_ctl <0x%x>, xid <0x%x>\n" , |
2621 | f_ctl, |
2622 | (f_ctl & FC_FC_EX_CTX) ? |
2623 | ntohs(fh->fh_ox_id) : |
2624 | ntohs(fh->fh_rx_id)); |
2625 | fc_frame_free(fp); |
2626 | return; |
2627 | } |
2628 | |
2629 | /* |
2630 | * If frame is marked invalid, just drop it. |
2631 | */ |
2632 | switch (fr_eof(fp)) { |
2633 | case FC_EOF_T: |
2634 | if (f_ctl & FC_FC_END_SEQ) |
2635 | skb_trim(fp_skb(fp), fr_len(fp) - FC_FC_FILL(f_ctl)); |
2636 | fallthrough; |
2637 | case FC_EOF_N: |
2638 | if (fh->fh_type == FC_TYPE_BLS) |
2639 | fc_exch_recv_bls(mp: ema->mp, fp); |
2640 | else if ((f_ctl & (FC_FC_EX_CTX | FC_FC_SEQ_CTX)) == |
2641 | FC_FC_EX_CTX) |
2642 | fc_exch_recv_seq_resp(mp: ema->mp, fp); |
2643 | else if (f_ctl & FC_FC_SEQ_CTX) |
2644 | fc_exch_recv_resp(mp: ema->mp, fp); |
2645 | else /* no EX_CTX and no SEQ_CTX */ |
2646 | fc_exch_recv_req(lport, mp: ema->mp, fp); |
2647 | break; |
2648 | default: |
2649 | FC_LPORT_DBG(lport, "dropping invalid frame (eof %x)" , |
2650 | fr_eof(fp)); |
2651 | fc_frame_free(fp); |
2652 | } |
2653 | } |
2654 | EXPORT_SYMBOL(fc_exch_recv); |
2655 | |
2656 | /** |
2657 | * fc_exch_init() - Initialize the exchange layer for a local port |
2658 | * @lport: The local port to initialize the exchange layer for |
2659 | */ |
2660 | int fc_exch_init(struct fc_lport *lport) |
2661 | { |
2662 | if (!lport->tt.exch_mgr_reset) |
2663 | lport->tt.exch_mgr_reset = fc_exch_mgr_reset; |
2664 | |
2665 | return 0; |
2666 | } |
2667 | EXPORT_SYMBOL(fc_exch_init); |
2668 | |
2669 | /** |
2670 | * fc_setup_exch_mgr() - Setup an exchange manager |
2671 | */ |
2672 | int fc_setup_exch_mgr(void) |
2673 | { |
2674 | fc_em_cachep = kmem_cache_create(name: "libfc_em" , size: sizeof(struct fc_exch), |
2675 | align: 0, SLAB_HWCACHE_ALIGN, NULL); |
2676 | if (!fc_em_cachep) |
2677 | return -ENOMEM; |
2678 | |
2679 | /* |
2680 | * Initialize fc_cpu_mask and fc_cpu_order. The |
2681 | * fc_cpu_mask is set for nr_cpu_ids rounded up |
2682 | * to order of 2's * power and order is stored |
2683 | * in fc_cpu_order as this is later required in |
2684 | * mapping between an exch id and exch array index |
2685 | * in per cpu exch pool. |
2686 | * |
2687 | * This round up is required to align fc_cpu_mask |
2688 | * to exchange id's lower bits such that all incoming |
2689 | * frames of an exchange gets delivered to the same |
2690 | * cpu on which exchange originated by simple bitwise |
2691 | * AND operation between fc_cpu_mask and exchange id. |
2692 | */ |
2693 | fc_cpu_order = ilog2(roundup_pow_of_two(nr_cpu_ids)); |
2694 | fc_cpu_mask = (1 << fc_cpu_order) - 1; |
2695 | |
2696 | fc_exch_workqueue = create_singlethread_workqueue("fc_exch_workqueue" ); |
2697 | if (!fc_exch_workqueue) |
2698 | goto err; |
2699 | return 0; |
2700 | err: |
2701 | kmem_cache_destroy(s: fc_em_cachep); |
2702 | return -ENOMEM; |
2703 | } |
2704 | |
2705 | /** |
2706 | * fc_destroy_exch_mgr() - Destroy an exchange manager |
2707 | */ |
2708 | void fc_destroy_exch_mgr(void) |
2709 | { |
2710 | destroy_workqueue(wq: fc_exch_workqueue); |
2711 | kmem_cache_destroy(s: fc_em_cachep); |
2712 | } |
2713 | |