xref: /linux/drivers/scsi/qedf/qedf_els.c (revision 8a79db5e83a5d52c74e6f3c40d6f312cf899213e)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  QLogic FCoE Offload Driver
4  *  Copyright (c) 2016-2018 Cavium Inc.
5  */
6 #include "qedf.h"
7 
8 /* It's assumed that the lock is held when calling this function. */
9 static int qedf_initiate_els(struct qedf_rport *fcport, unsigned int op,
10 	void *data, uint32_t data_len,
11 	void (*cb_func)(struct qedf_els_cb_arg *cb_arg),
12 	struct qedf_els_cb_arg *cb_arg, uint32_t timer_msec)
13 {
14 	struct qedf_ctx *qedf;
15 	struct fc_lport *lport;
16 	struct qedf_ioreq *els_req;
17 	struct qedf_mp_req *mp_req;
18 	struct fc_frame_header *fc_hdr;
19 	struct e4_fcoe_task_context *task;
20 	int rc = 0;
21 	uint32_t did, sid;
22 	uint16_t xid;
23 	struct fcoe_wqe *sqe;
24 	unsigned long flags;
25 	u16 sqe_idx;
26 
27 	if (!fcport) {
28 		QEDF_ERR(NULL, "fcport is NULL");
29 		rc = -EINVAL;
30 		goto els_err;
31 	}
32 
33 	qedf = fcport->qedf;
34 	lport = qedf->lport;
35 
36 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Sending ELS\n");
37 
38 	rc = fc_remote_port_chkready(fcport->rport);
39 	if (rc) {
40 		QEDF_ERR(&(qedf->dbg_ctx), "els 0x%x: rport not ready\n", op);
41 		rc = -EAGAIN;
42 		goto els_err;
43 	}
44 	if (lport->state != LPORT_ST_READY || !(lport->link_up)) {
45 		QEDF_ERR(&(qedf->dbg_ctx), "els 0x%x: link is not ready\n",
46 			  op);
47 		rc = -EAGAIN;
48 		goto els_err;
49 	}
50 
51 	if (!test_bit(QEDF_RPORT_SESSION_READY, &fcport->flags)) {
52 		QEDF_ERR(&(qedf->dbg_ctx), "els 0x%x: fcport not ready\n", op);
53 		rc = -EINVAL;
54 		goto els_err;
55 	}
56 
57 	els_req = qedf_alloc_cmd(fcport, QEDF_ELS);
58 	if (!els_req) {
59 		QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_ELS,
60 			  "Failed to alloc ELS request 0x%x\n", op);
61 		rc = -ENOMEM;
62 		goto els_err;
63 	}
64 
65 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "initiate_els els_req = "
66 		   "0x%p cb_arg = %p xid = %x\n", els_req, cb_arg,
67 		   els_req->xid);
68 	els_req->sc_cmd = NULL;
69 	els_req->cmd_type = QEDF_ELS;
70 	els_req->fcport = fcport;
71 	els_req->cb_func = cb_func;
72 	cb_arg->io_req = els_req;
73 	cb_arg->op = op;
74 	els_req->cb_arg = cb_arg;
75 	els_req->data_xfer_len = data_len;
76 
77 	/* Record which cpu this request is associated with */
78 	els_req->cpu = smp_processor_id();
79 
80 	mp_req = (struct qedf_mp_req *)&(els_req->mp_req);
81 	rc = qedf_init_mp_req(els_req);
82 	if (rc) {
83 		QEDF_ERR(&(qedf->dbg_ctx), "ELS MP request init failed\n");
84 		kref_put(&els_req->refcount, qedf_release_cmd);
85 		goto els_err;
86 	} else {
87 		rc = 0;
88 	}
89 
90 	/* Fill ELS Payload */
91 	if ((op >= ELS_LS_RJT) && (op <= ELS_AUTH_ELS)) {
92 		memcpy(mp_req->req_buf, data, data_len);
93 	} else {
94 		QEDF_ERR(&(qedf->dbg_ctx), "Invalid ELS op 0x%x\n", op);
95 		els_req->cb_func = NULL;
96 		els_req->cb_arg = NULL;
97 		kref_put(&els_req->refcount, qedf_release_cmd);
98 		rc = -EINVAL;
99 	}
100 
101 	if (rc)
102 		goto els_err;
103 
104 	/* Fill FC header */
105 	fc_hdr = &(mp_req->req_fc_hdr);
106 
107 	did = fcport->rdata->ids.port_id;
108 	sid = fcport->sid;
109 
110 	__fc_fill_fc_hdr(fc_hdr, FC_RCTL_ELS_REQ, did, sid,
111 			   FC_TYPE_ELS, FC_FC_FIRST_SEQ | FC_FC_END_SEQ |
112 			   FC_FC_SEQ_INIT, 0);
113 
114 	/* Obtain exchange id */
115 	xid = els_req->xid;
116 
117 	spin_lock_irqsave(&fcport->rport_lock, flags);
118 
119 	sqe_idx = qedf_get_sqe_idx(fcport);
120 	sqe = &fcport->sq[sqe_idx];
121 	memset(sqe, 0, sizeof(struct fcoe_wqe));
122 
123 	/* Initialize task context for this IO request */
124 	task = qedf_get_task_mem(&qedf->tasks, xid);
125 	qedf_init_mp_task(els_req, task, sqe);
126 
127 	/* Put timer on original I/O request */
128 	if (timer_msec)
129 		qedf_cmd_timer_set(qedf, els_req, timer_msec);
130 
131 	/* Ring doorbell */
132 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Ringing doorbell for ELS "
133 		   "req\n");
134 	qedf_ring_doorbell(fcport);
135 	set_bit(QEDF_CMD_OUTSTANDING, &els_req->flags);
136 
137 	spin_unlock_irqrestore(&fcport->rport_lock, flags);
138 els_err:
139 	return rc;
140 }
141 
142 void qedf_process_els_compl(struct qedf_ctx *qedf, struct fcoe_cqe *cqe,
143 	struct qedf_ioreq *els_req)
144 {
145 	struct fcoe_cqe_midpath_info *mp_info;
146 
147 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Entered with xid = 0x%x"
148 		   " cmd_type = %d.\n", els_req->xid, els_req->cmd_type);
149 
150 	clear_bit(QEDF_CMD_OUTSTANDING, &els_req->flags);
151 
152 	/* Kill the ELS timer */
153 	cancel_delayed_work(&els_req->timeout_work);
154 
155 	/* Get ELS response length from CQE */
156 	mp_info = &cqe->cqe_info.midpath_info;
157 	els_req->mp_req.resp_len = mp_info->data_placement_size;
158 
159 	/* Parse ELS response */
160 	if ((els_req->cb_func) && (els_req->cb_arg)) {
161 		els_req->cb_func(els_req->cb_arg);
162 		els_req->cb_arg = NULL;
163 	}
164 
165 	kref_put(&els_req->refcount, qedf_release_cmd);
166 }
167 
168 static void qedf_rrq_compl(struct qedf_els_cb_arg *cb_arg)
169 {
170 	struct qedf_ioreq *orig_io_req;
171 	struct qedf_ioreq *rrq_req;
172 	struct qedf_ctx *qedf;
173 	int refcount;
174 
175 	rrq_req = cb_arg->io_req;
176 	qedf = rrq_req->fcport->qedf;
177 
178 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Entered.\n");
179 
180 	orig_io_req = cb_arg->aborted_io_req;
181 
182 	if (!orig_io_req) {
183 		QEDF_ERR(&qedf->dbg_ctx,
184 			 "Original io_req is NULL, rrq_req = %p.\n", rrq_req);
185 		goto out_free;
186 	}
187 
188 	if (rrq_req->event != QEDF_IOREQ_EV_ELS_TMO &&
189 	    rrq_req->event != QEDF_IOREQ_EV_ELS_ERR_DETECT)
190 		cancel_delayed_work_sync(&orig_io_req->timeout_work);
191 
192 	refcount = kref_read(&orig_io_req->refcount);
193 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "rrq_compl: orig io = %p,"
194 		   " orig xid = 0x%x, rrq_xid = 0x%x, refcount=%d\n",
195 		   orig_io_req, orig_io_req->xid, rrq_req->xid, refcount);
196 
197 	/*
198 	 * This should return the aborted io_req to the command pool. Note that
199 	 * we need to check the refcound in case the original request was
200 	 * flushed but we get a completion on this xid.
201 	 */
202 	if (orig_io_req && refcount > 0)
203 		kref_put(&orig_io_req->refcount, qedf_release_cmd);
204 
205 out_free:
206 	/*
207 	 * Release a reference to the rrq request if we timed out as the
208 	 * rrq completion handler is called directly from the timeout handler
209 	 * and not from els_compl where the reference would have normally been
210 	 * released.
211 	 */
212 	if (rrq_req->event == QEDF_IOREQ_EV_ELS_TMO)
213 		kref_put(&rrq_req->refcount, qedf_release_cmd);
214 	kfree(cb_arg);
215 }
216 
217 /* Assumes kref is already held by caller */
218 int qedf_send_rrq(struct qedf_ioreq *aborted_io_req)
219 {
220 
221 	struct fc_els_rrq rrq;
222 	struct qedf_rport *fcport;
223 	struct fc_lport *lport;
224 	struct qedf_els_cb_arg *cb_arg = NULL;
225 	struct qedf_ctx *qedf;
226 	uint32_t sid;
227 	uint32_t r_a_tov;
228 	int rc;
229 	int refcount;
230 
231 	if (!aborted_io_req) {
232 		QEDF_ERR(NULL, "abort_io_req is NULL.\n");
233 		return -EINVAL;
234 	}
235 
236 	fcport = aborted_io_req->fcport;
237 
238 	if (!fcport) {
239 		refcount = kref_read(&aborted_io_req->refcount);
240 		QEDF_ERR(NULL,
241 			 "RRQ work was queued prior to a flush xid=0x%x, refcount=%d.\n",
242 			 aborted_io_req->xid, refcount);
243 		kref_put(&aborted_io_req->refcount, qedf_release_cmd);
244 		return -EINVAL;
245 	}
246 
247 	/* Check that fcport is still offloaded */
248 	if (!test_bit(QEDF_RPORT_SESSION_READY, &fcport->flags)) {
249 		QEDF_ERR(NULL, "fcport is no longer offloaded.\n");
250 		return -EINVAL;
251 	}
252 
253 	if (!fcport->qedf) {
254 		QEDF_ERR(NULL, "fcport->qedf is NULL.\n");
255 		return -EINVAL;
256 	}
257 
258 	qedf = fcport->qedf;
259 
260 	/*
261 	 * Sanity check that we can send a RRQ to make sure that refcount isn't
262 	 * 0
263 	 */
264 	refcount = kref_read(&aborted_io_req->refcount);
265 	if (refcount != 1) {
266 		QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_ELS,
267 			  "refcount for xid=%x io_req=%p refcount=%d is not 1.\n",
268 			  aborted_io_req->xid, aborted_io_req, refcount);
269 		return -EINVAL;
270 	}
271 
272 	lport = qedf->lport;
273 	sid = fcport->sid;
274 	r_a_tov = lport->r_a_tov;
275 
276 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Sending RRQ orig "
277 		   "io = %p, orig_xid = 0x%x\n", aborted_io_req,
278 		   aborted_io_req->xid);
279 	memset(&rrq, 0, sizeof(rrq));
280 
281 	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
282 	if (!cb_arg) {
283 		QEDF_ERR(&(qedf->dbg_ctx), "Unable to allocate cb_arg for "
284 			  "RRQ\n");
285 		rc = -ENOMEM;
286 		goto rrq_err;
287 	}
288 
289 	cb_arg->aborted_io_req = aborted_io_req;
290 
291 	rrq.rrq_cmd = ELS_RRQ;
292 	hton24(rrq.rrq_s_id, sid);
293 	rrq.rrq_ox_id = htons(aborted_io_req->xid);
294 	rrq.rrq_rx_id =
295 	    htons(aborted_io_req->task->tstorm_st_context.read_write.rx_id);
296 
297 	rc = qedf_initiate_els(fcport, ELS_RRQ, &rrq, sizeof(rrq),
298 	    qedf_rrq_compl, cb_arg, r_a_tov);
299 
300 rrq_err:
301 	if (rc) {
302 		QEDF_ERR(&(qedf->dbg_ctx), "RRQ failed - release orig io "
303 			  "req 0x%x\n", aborted_io_req->xid);
304 		kfree(cb_arg);
305 		kref_put(&aborted_io_req->refcount, qedf_release_cmd);
306 	}
307 	return rc;
308 }
309 
310 static void qedf_process_l2_frame_compl(struct qedf_rport *fcport,
311 					struct fc_frame *fp,
312 					u16 l2_oxid)
313 {
314 	struct fc_lport *lport = fcport->qedf->lport;
315 	struct fc_frame_header *fh;
316 	u32 crc;
317 
318 	fh = (struct fc_frame_header *)fc_frame_header_get(fp);
319 
320 	/* Set the OXID we return to what libfc used */
321 	if (l2_oxid != FC_XID_UNKNOWN)
322 		fh->fh_ox_id = htons(l2_oxid);
323 
324 	/* Setup header fields */
325 	fh->fh_r_ctl = FC_RCTL_ELS_REP;
326 	fh->fh_type = FC_TYPE_ELS;
327 	/* Last sequence, end sequence */
328 	fh->fh_f_ctl[0] = 0x98;
329 	hton24(fh->fh_d_id, lport->port_id);
330 	hton24(fh->fh_s_id, fcport->rdata->ids.port_id);
331 	fh->fh_rx_id = 0xffff;
332 
333 	/* Set frame attributes */
334 	crc = fcoe_fc_crc(fp);
335 	fc_frame_init(fp);
336 	fr_dev(fp) = lport;
337 	fr_sof(fp) = FC_SOF_I3;
338 	fr_eof(fp) = FC_EOF_T;
339 	fr_crc(fp) = cpu_to_le32(~crc);
340 
341 	/* Send completed request to libfc */
342 	fc_exch_recv(lport, fp);
343 }
344 
345 /*
346  * In instances where an ELS command times out we may need to restart the
347  * rport by logging out and then logging back in.
348  */
349 void qedf_restart_rport(struct qedf_rport *fcport)
350 {
351 	struct fc_lport *lport;
352 	struct fc_rport_priv *rdata;
353 	u32 port_id;
354 	unsigned long flags;
355 
356 	if (!fcport) {
357 		QEDF_ERR(NULL, "fcport is NULL.\n");
358 		return;
359 	}
360 
361 	spin_lock_irqsave(&fcport->rport_lock, flags);
362 	if (test_bit(QEDF_RPORT_IN_RESET, &fcport->flags) ||
363 	    !test_bit(QEDF_RPORT_SESSION_READY, &fcport->flags) ||
364 	    test_bit(QEDF_RPORT_UPLOADING_CONNECTION, &fcport->flags)) {
365 		QEDF_ERR(&(fcport->qedf->dbg_ctx), "fcport %p already in reset or not offloaded.\n",
366 		    fcport);
367 		spin_unlock_irqrestore(&fcport->rport_lock, flags);
368 		return;
369 	}
370 
371 	/* Set that we are now in reset */
372 	set_bit(QEDF_RPORT_IN_RESET, &fcport->flags);
373 	spin_unlock_irqrestore(&fcport->rport_lock, flags);
374 
375 	rdata = fcport->rdata;
376 	if (rdata && !kref_get_unless_zero(&rdata->kref)) {
377 		fcport->rdata = NULL;
378 		rdata = NULL;
379 	}
380 
381 	if (rdata && rdata->rp_state == RPORT_ST_READY) {
382 		lport = fcport->qedf->lport;
383 		port_id = rdata->ids.port_id;
384 		QEDF_ERR(&(fcport->qedf->dbg_ctx),
385 		    "LOGO port_id=%x.\n", port_id);
386 		fc_rport_logoff(rdata);
387 		kref_put(&rdata->kref, fc_rport_destroy);
388 		mutex_lock(&lport->disc.disc_mutex);
389 		/* Recreate the rport and log back in */
390 		rdata = fc_rport_create(lport, port_id);
391 		if (rdata) {
392 			mutex_unlock(&lport->disc.disc_mutex);
393 			fc_rport_login(rdata);
394 			fcport->rdata = rdata;
395 		} else {
396 			mutex_unlock(&lport->disc.disc_mutex);
397 			fcport->rdata = NULL;
398 		}
399 	}
400 	clear_bit(QEDF_RPORT_IN_RESET, &fcport->flags);
401 }
402 
403 static void qedf_l2_els_compl(struct qedf_els_cb_arg *cb_arg)
404 {
405 	struct qedf_ioreq *els_req;
406 	struct qedf_rport *fcport;
407 	struct qedf_mp_req *mp_req;
408 	struct fc_frame *fp;
409 	struct fc_frame_header *fh, *mp_fc_hdr;
410 	void *resp_buf, *fc_payload;
411 	u32 resp_len;
412 	u16 l2_oxid;
413 
414 	l2_oxid = cb_arg->l2_oxid;
415 	els_req = cb_arg->io_req;
416 
417 	if (!els_req) {
418 		QEDF_ERR(NULL, "els_req is NULL.\n");
419 		goto free_arg;
420 	}
421 
422 	/*
423 	 * If we are flushing the command just free the cb_arg as none of the
424 	 * response data will be valid.
425 	 */
426 	if (els_req->event == QEDF_IOREQ_EV_ELS_FLUSH) {
427 		QEDF_ERR(NULL, "els_req xid=0x%x event is flush.\n",
428 			 els_req->xid);
429 		goto free_arg;
430 	}
431 
432 	fcport = els_req->fcport;
433 	mp_req = &(els_req->mp_req);
434 	mp_fc_hdr = &(mp_req->resp_fc_hdr);
435 	resp_len = mp_req->resp_len;
436 	resp_buf = mp_req->resp_buf;
437 
438 	/*
439 	 * If a middle path ELS command times out, don't try to return
440 	 * the command but rather do any internal cleanup and then libfc
441 	 * timeout the command and clean up its internal resources.
442 	 */
443 	if (els_req->event == QEDF_IOREQ_EV_ELS_TMO) {
444 		/*
445 		 * If ADISC times out, libfc will timeout the exchange and then
446 		 * try to send a PLOGI which will timeout since the session is
447 		 * still offloaded.  Force libfc to logout the session which
448 		 * will offload the connection and allow the PLOGI response to
449 		 * flow over the LL2 path.
450 		 */
451 		if (cb_arg->op == ELS_ADISC)
452 			qedf_restart_rport(fcport);
453 		return;
454 	}
455 
456 	if (sizeof(struct fc_frame_header) + resp_len > QEDF_PAGE_SIZE) {
457 		QEDF_ERR(&(fcport->qedf->dbg_ctx), "resp_len is "
458 		   "beyond page size.\n");
459 		goto free_arg;
460 	}
461 
462 	fp = fc_frame_alloc(fcport->qedf->lport, resp_len);
463 	if (!fp) {
464 		QEDF_ERR(&(fcport->qedf->dbg_ctx),
465 		    "fc_frame_alloc failure.\n");
466 		return;
467 	}
468 
469 	/* Copy frame header from firmware into fp */
470 	fh = (struct fc_frame_header *)fc_frame_header_get(fp);
471 	memcpy(fh, mp_fc_hdr, sizeof(struct fc_frame_header));
472 
473 	/* Copy payload from firmware into fp */
474 	fc_payload = fc_frame_payload_get(fp, resp_len);
475 	memcpy(fc_payload, resp_buf, resp_len);
476 
477 	QEDF_INFO(&(fcport->qedf->dbg_ctx), QEDF_LOG_ELS,
478 	    "Completing OX_ID 0x%x back to libfc.\n", l2_oxid);
479 	qedf_process_l2_frame_compl(fcport, fp, l2_oxid);
480 
481 free_arg:
482 	kfree(cb_arg);
483 }
484 
485 int qedf_send_adisc(struct qedf_rport *fcport, struct fc_frame *fp)
486 {
487 	struct fc_els_adisc *adisc;
488 	struct fc_frame_header *fh;
489 	struct fc_lport *lport = fcport->qedf->lport;
490 	struct qedf_els_cb_arg *cb_arg = NULL;
491 	struct qedf_ctx *qedf;
492 	uint32_t r_a_tov = lport->r_a_tov;
493 	int rc;
494 
495 	qedf = fcport->qedf;
496 	fh = fc_frame_header_get(fp);
497 
498 	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
499 	if (!cb_arg) {
500 		QEDF_ERR(&(qedf->dbg_ctx), "Unable to allocate cb_arg for "
501 			  "ADISC\n");
502 		rc = -ENOMEM;
503 		goto adisc_err;
504 	}
505 	cb_arg->l2_oxid = ntohs(fh->fh_ox_id);
506 
507 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
508 	    "Sending ADISC ox_id=0x%x.\n", cb_arg->l2_oxid);
509 
510 	adisc = fc_frame_payload_get(fp, sizeof(*adisc));
511 
512 	rc = qedf_initiate_els(fcport, ELS_ADISC, adisc, sizeof(*adisc),
513 	    qedf_l2_els_compl, cb_arg, r_a_tov);
514 
515 adisc_err:
516 	if (rc) {
517 		QEDF_ERR(&(qedf->dbg_ctx), "ADISC failed.\n");
518 		kfree(cb_arg);
519 	}
520 	return rc;
521 }
522 
523 static void qedf_srr_compl(struct qedf_els_cb_arg *cb_arg)
524 {
525 	struct qedf_ioreq *orig_io_req;
526 	struct qedf_ioreq *srr_req;
527 	struct qedf_mp_req *mp_req;
528 	struct fc_frame_header *mp_fc_hdr, *fh;
529 	struct fc_frame *fp;
530 	void *resp_buf, *fc_payload;
531 	u32 resp_len;
532 	struct fc_lport *lport;
533 	struct qedf_ctx *qedf;
534 	int refcount;
535 	u8 opcode;
536 
537 	srr_req = cb_arg->io_req;
538 	qedf = srr_req->fcport->qedf;
539 	lport = qedf->lport;
540 
541 	orig_io_req = cb_arg->aborted_io_req;
542 
543 	if (!orig_io_req) {
544 		QEDF_ERR(NULL, "orig_io_req is NULL.\n");
545 		goto out_free;
546 	}
547 
548 	clear_bit(QEDF_CMD_SRR_SENT, &orig_io_req->flags);
549 
550 	if (srr_req->event != QEDF_IOREQ_EV_ELS_TMO &&
551 	    srr_req->event != QEDF_IOREQ_EV_ELS_ERR_DETECT)
552 		cancel_delayed_work_sync(&orig_io_req->timeout_work);
553 
554 	refcount = kref_read(&orig_io_req->refcount);
555 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Entered: orig_io=%p,"
556 		   " orig_io_xid=0x%x, rec_xid=0x%x, refcount=%d\n",
557 		   orig_io_req, orig_io_req->xid, srr_req->xid, refcount);
558 
559 	/* If a SRR times out, simply free resources */
560 	if (srr_req->event == QEDF_IOREQ_EV_ELS_TMO) {
561 		QEDF_ERR(&qedf->dbg_ctx,
562 			 "ELS timeout rec_xid=0x%x.\n", srr_req->xid);
563 		goto out_put;
564 	}
565 
566 	/* Normalize response data into struct fc_frame */
567 	mp_req = &(srr_req->mp_req);
568 	mp_fc_hdr = &(mp_req->resp_fc_hdr);
569 	resp_len = mp_req->resp_len;
570 	resp_buf = mp_req->resp_buf;
571 
572 	fp = fc_frame_alloc(lport, resp_len);
573 	if (!fp) {
574 		QEDF_ERR(&(qedf->dbg_ctx),
575 		    "fc_frame_alloc failure.\n");
576 		goto out_put;
577 	}
578 
579 	/* Copy frame header from firmware into fp */
580 	fh = (struct fc_frame_header *)fc_frame_header_get(fp);
581 	memcpy(fh, mp_fc_hdr, sizeof(struct fc_frame_header));
582 
583 	/* Copy payload from firmware into fp */
584 	fc_payload = fc_frame_payload_get(fp, resp_len);
585 	memcpy(fc_payload, resp_buf, resp_len);
586 
587 	opcode = fc_frame_payload_op(fp);
588 	switch (opcode) {
589 	case ELS_LS_ACC:
590 		QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
591 		    "SRR success.\n");
592 		break;
593 	case ELS_LS_RJT:
594 		QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_ELS,
595 		    "SRR rejected.\n");
596 		qedf_initiate_abts(orig_io_req, true);
597 		break;
598 	}
599 
600 	fc_frame_free(fp);
601 out_put:
602 	/* Put reference for original command since SRR completed */
603 	kref_put(&orig_io_req->refcount, qedf_release_cmd);
604 out_free:
605 	kfree(cb_arg);
606 }
607 
608 static int qedf_send_srr(struct qedf_ioreq *orig_io_req, u32 offset, u8 r_ctl)
609 {
610 	struct fcp_srr srr;
611 	struct qedf_ctx *qedf;
612 	struct qedf_rport *fcport;
613 	struct fc_lport *lport;
614 	struct qedf_els_cb_arg *cb_arg = NULL;
615 	u32 r_a_tov;
616 	int rc;
617 
618 	if (!orig_io_req) {
619 		QEDF_ERR(NULL, "orig_io_req is NULL.\n");
620 		return -EINVAL;
621 	}
622 
623 	fcport = orig_io_req->fcport;
624 
625 	/* Check that fcport is still offloaded */
626 	if (!test_bit(QEDF_RPORT_SESSION_READY, &fcport->flags)) {
627 		QEDF_ERR(NULL, "fcport is no longer offloaded.\n");
628 		return -EINVAL;
629 	}
630 
631 	if (!fcport->qedf) {
632 		QEDF_ERR(NULL, "fcport->qedf is NULL.\n");
633 		return -EINVAL;
634 	}
635 
636 	/* Take reference until SRR command completion */
637 	kref_get(&orig_io_req->refcount);
638 
639 	qedf = fcport->qedf;
640 	lport = qedf->lport;
641 	r_a_tov = lport->r_a_tov;
642 
643 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Sending SRR orig_io=%p, "
644 		   "orig_xid=0x%x\n", orig_io_req, orig_io_req->xid);
645 	memset(&srr, 0, sizeof(srr));
646 
647 	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
648 	if (!cb_arg) {
649 		QEDF_ERR(&(qedf->dbg_ctx), "Unable to allocate cb_arg for "
650 			  "SRR\n");
651 		rc = -ENOMEM;
652 		goto srr_err;
653 	}
654 
655 	cb_arg->aborted_io_req = orig_io_req;
656 
657 	srr.srr_op = ELS_SRR;
658 	srr.srr_ox_id = htons(orig_io_req->xid);
659 	srr.srr_rx_id = htons(orig_io_req->rx_id);
660 	srr.srr_rel_off = htonl(offset);
661 	srr.srr_r_ctl = r_ctl;
662 
663 	rc = qedf_initiate_els(fcport, ELS_SRR, &srr, sizeof(srr),
664 	    qedf_srr_compl, cb_arg, r_a_tov);
665 
666 srr_err:
667 	if (rc) {
668 		QEDF_ERR(&(qedf->dbg_ctx), "SRR failed - release orig_io_req"
669 			  "=0x%x\n", orig_io_req->xid);
670 		kfree(cb_arg);
671 		/* If we fail to queue SRR, send ABTS to orig_io */
672 		qedf_initiate_abts(orig_io_req, true);
673 		kref_put(&orig_io_req->refcount, qedf_release_cmd);
674 	} else
675 		/* Tell other threads that SRR is in progress */
676 		set_bit(QEDF_CMD_SRR_SENT, &orig_io_req->flags);
677 
678 	return rc;
679 }
680 
681 static void qedf_initiate_seq_cleanup(struct qedf_ioreq *orig_io_req,
682 	u32 offset, u8 r_ctl)
683 {
684 	struct qedf_rport *fcport;
685 	unsigned long flags;
686 	struct qedf_els_cb_arg *cb_arg;
687 	struct fcoe_wqe *sqe;
688 	u16 sqe_idx;
689 
690 	fcport = orig_io_req->fcport;
691 
692 	QEDF_INFO(&(fcport->qedf->dbg_ctx), QEDF_LOG_ELS,
693 	    "Doing sequence cleanup for xid=0x%x offset=%u.\n",
694 	    orig_io_req->xid, offset);
695 
696 	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
697 	if (!cb_arg) {
698 		QEDF_ERR(&(fcport->qedf->dbg_ctx), "Unable to allocate cb_arg "
699 			  "for sequence cleanup\n");
700 		return;
701 	}
702 
703 	/* Get reference for cleanup request */
704 	kref_get(&orig_io_req->refcount);
705 
706 	orig_io_req->cmd_type = QEDF_SEQ_CLEANUP;
707 	cb_arg->offset = offset;
708 	cb_arg->r_ctl = r_ctl;
709 	orig_io_req->cb_arg = cb_arg;
710 
711 	qedf_cmd_timer_set(fcport->qedf, orig_io_req,
712 	    QEDF_CLEANUP_TIMEOUT * HZ);
713 
714 	spin_lock_irqsave(&fcport->rport_lock, flags);
715 
716 	sqe_idx = qedf_get_sqe_idx(fcport);
717 	sqe = &fcport->sq[sqe_idx];
718 	memset(sqe, 0, sizeof(struct fcoe_wqe));
719 	orig_io_req->task_params->sqe = sqe;
720 
721 	init_initiator_sequence_recovery_fcoe_task(orig_io_req->task_params,
722 						   offset);
723 	qedf_ring_doorbell(fcport);
724 
725 	spin_unlock_irqrestore(&fcport->rport_lock, flags);
726 }
727 
728 void qedf_process_seq_cleanup_compl(struct qedf_ctx *qedf,
729 	struct fcoe_cqe *cqe, struct qedf_ioreq *io_req)
730 {
731 	int rc;
732 	struct qedf_els_cb_arg *cb_arg;
733 
734 	cb_arg = io_req->cb_arg;
735 
736 	/* If we timed out just free resources */
737 	if (io_req->event == QEDF_IOREQ_EV_ELS_TMO || !cqe) {
738 		QEDF_ERR(&qedf->dbg_ctx,
739 			 "cqe is NULL or timeout event (0x%x)", io_req->event);
740 		goto free;
741 	}
742 
743 	/* Kill the timer we put on the request */
744 	cancel_delayed_work_sync(&io_req->timeout_work);
745 
746 	rc = qedf_send_srr(io_req, cb_arg->offset, cb_arg->r_ctl);
747 	if (rc)
748 		QEDF_ERR(&(qedf->dbg_ctx), "Unable to send SRR, I/O will "
749 		    "abort, xid=0x%x.\n", io_req->xid);
750 free:
751 	kfree(cb_arg);
752 	kref_put(&io_req->refcount, qedf_release_cmd);
753 }
754 
755 static bool qedf_requeue_io_req(struct qedf_ioreq *orig_io_req)
756 {
757 	struct qedf_rport *fcport;
758 	struct qedf_ioreq *new_io_req;
759 	unsigned long flags;
760 	bool rc = false;
761 
762 	fcport = orig_io_req->fcport;
763 	if (!fcport) {
764 		QEDF_ERR(NULL, "fcport is NULL.\n");
765 		goto out;
766 	}
767 
768 	if (!orig_io_req->sc_cmd) {
769 		QEDF_ERR(&(fcport->qedf->dbg_ctx), "sc_cmd is NULL for "
770 		    "xid=0x%x.\n", orig_io_req->xid);
771 		goto out;
772 	}
773 
774 	new_io_req = qedf_alloc_cmd(fcport, QEDF_SCSI_CMD);
775 	if (!new_io_req) {
776 		QEDF_ERR(&(fcport->qedf->dbg_ctx), "Could not allocate new "
777 		    "io_req.\n");
778 		goto out;
779 	}
780 
781 	new_io_req->sc_cmd = orig_io_req->sc_cmd;
782 
783 	/*
784 	 * This keeps the sc_cmd struct from being returned to the tape
785 	 * driver and being requeued twice. We do need to put a reference
786 	 * for the original I/O request since we will not do a SCSI completion
787 	 * for it.
788 	 */
789 	orig_io_req->sc_cmd = NULL;
790 	kref_put(&orig_io_req->refcount, qedf_release_cmd);
791 
792 	spin_lock_irqsave(&fcport->rport_lock, flags);
793 
794 	/* kref for new command released in qedf_post_io_req on error */
795 	if (qedf_post_io_req(fcport, new_io_req)) {
796 		QEDF_ERR(&(fcport->qedf->dbg_ctx), "Unable to post io_req\n");
797 		/* Return SQE to pool */
798 		atomic_inc(&fcport->free_sqes);
799 	} else {
800 		QEDF_INFO(&(fcport->qedf->dbg_ctx), QEDF_LOG_ELS,
801 		    "Reissued SCSI command from  orig_xid=0x%x on "
802 		    "new_xid=0x%x.\n", orig_io_req->xid, new_io_req->xid);
803 		/*
804 		 * Abort the original I/O but do not return SCSI command as
805 		 * it has been reissued on another OX_ID.
806 		 */
807 		spin_unlock_irqrestore(&fcport->rport_lock, flags);
808 		qedf_initiate_abts(orig_io_req, false);
809 		goto out;
810 	}
811 
812 	spin_unlock_irqrestore(&fcport->rport_lock, flags);
813 out:
814 	return rc;
815 }
816 
817 
818 static void qedf_rec_compl(struct qedf_els_cb_arg *cb_arg)
819 {
820 	struct qedf_ioreq *orig_io_req;
821 	struct qedf_ioreq *rec_req;
822 	struct qedf_mp_req *mp_req;
823 	struct fc_frame_header *mp_fc_hdr, *fh;
824 	struct fc_frame *fp;
825 	void *resp_buf, *fc_payload;
826 	u32 resp_len;
827 	struct fc_lport *lport;
828 	struct qedf_ctx *qedf;
829 	int refcount;
830 	enum fc_rctl r_ctl;
831 	struct fc_els_ls_rjt *rjt;
832 	struct fc_els_rec_acc *acc;
833 	u8 opcode;
834 	u32 offset, e_stat;
835 	struct scsi_cmnd *sc_cmd;
836 	bool srr_needed = false;
837 
838 	rec_req = cb_arg->io_req;
839 	qedf = rec_req->fcport->qedf;
840 	lport = qedf->lport;
841 
842 	orig_io_req = cb_arg->aborted_io_req;
843 
844 	if (!orig_io_req) {
845 		QEDF_ERR(NULL, "orig_io_req is NULL.\n");
846 		goto out_free;
847 	}
848 
849 	if (rec_req->event != QEDF_IOREQ_EV_ELS_TMO &&
850 	    rec_req->event != QEDF_IOREQ_EV_ELS_ERR_DETECT)
851 		cancel_delayed_work_sync(&orig_io_req->timeout_work);
852 
853 	refcount = kref_read(&orig_io_req->refcount);
854 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Entered: orig_io=%p,"
855 		   " orig_io_xid=0x%x, rec_xid=0x%x, refcount=%d\n",
856 		   orig_io_req, orig_io_req->xid, rec_req->xid, refcount);
857 
858 	/* If a REC times out, free resources */
859 	if (rec_req->event == QEDF_IOREQ_EV_ELS_TMO) {
860 		QEDF_ERR(&qedf->dbg_ctx,
861 			 "Got TMO event, orig_io_req %p orig_io_xid=0x%x.\n",
862 			 orig_io_req, orig_io_req->xid);
863 		goto out_put;
864 	}
865 
866 	/* Normalize response data into struct fc_frame */
867 	mp_req = &(rec_req->mp_req);
868 	mp_fc_hdr = &(mp_req->resp_fc_hdr);
869 	resp_len = mp_req->resp_len;
870 	acc = resp_buf = mp_req->resp_buf;
871 
872 	fp = fc_frame_alloc(lport, resp_len);
873 	if (!fp) {
874 		QEDF_ERR(&(qedf->dbg_ctx),
875 		    "fc_frame_alloc failure.\n");
876 		goto out_put;
877 	}
878 
879 	/* Copy frame header from firmware into fp */
880 	fh = (struct fc_frame_header *)fc_frame_header_get(fp);
881 	memcpy(fh, mp_fc_hdr, sizeof(struct fc_frame_header));
882 
883 	/* Copy payload from firmware into fp */
884 	fc_payload = fc_frame_payload_get(fp, resp_len);
885 	memcpy(fc_payload, resp_buf, resp_len);
886 
887 	opcode = fc_frame_payload_op(fp);
888 	if (opcode == ELS_LS_RJT) {
889 		rjt = fc_frame_payload_get(fp, sizeof(*rjt));
890 		QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
891 		    "Received LS_RJT for REC: er_reason=0x%x, "
892 		    "er_explan=0x%x.\n", rjt->er_reason, rjt->er_explan);
893 		/*
894 		 * The following response(s) mean that we need to reissue the
895 		 * request on another exchange.  We need to do this without
896 		 * informing the upper layers lest it cause an application
897 		 * error.
898 		 */
899 		if ((rjt->er_reason == ELS_RJT_LOGIC ||
900 		    rjt->er_reason == ELS_RJT_UNAB) &&
901 		    rjt->er_explan == ELS_EXPL_OXID_RXID) {
902 			QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
903 			    "Handle CMD LOST case.\n");
904 			qedf_requeue_io_req(orig_io_req);
905 		}
906 	} else if (opcode == ELS_LS_ACC) {
907 		offset = ntohl(acc->reca_fc4value);
908 		e_stat = ntohl(acc->reca_e_stat);
909 		QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
910 		    "Received LS_ACC for REC: offset=0x%x, e_stat=0x%x.\n",
911 		    offset, e_stat);
912 		if (e_stat & ESB_ST_SEQ_INIT)  {
913 			QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
914 			    "Target has the seq init\n");
915 			goto out_free_frame;
916 		}
917 		sc_cmd = orig_io_req->sc_cmd;
918 		if (!sc_cmd) {
919 			QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
920 			    "sc_cmd is NULL for xid=0x%x.\n",
921 			    orig_io_req->xid);
922 			goto out_free_frame;
923 		}
924 		/* SCSI write case */
925 		if (sc_cmd->sc_data_direction == DMA_TO_DEVICE) {
926 			if (offset == orig_io_req->data_xfer_len) {
927 				QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
928 				    "WRITE - response lost.\n");
929 				r_ctl = FC_RCTL_DD_CMD_STATUS;
930 				srr_needed = true;
931 				offset = 0;
932 			} else {
933 				QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
934 				    "WRITE - XFER_RDY/DATA lost.\n");
935 				r_ctl = FC_RCTL_DD_DATA_DESC;
936 				/* Use data from warning CQE instead of REC */
937 				offset = orig_io_req->tx_buf_off;
938 			}
939 		/* SCSI read case */
940 		} else {
941 			if (orig_io_req->rx_buf_off ==
942 			    orig_io_req->data_xfer_len) {
943 				QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
944 				    "READ - response lost.\n");
945 				srr_needed = true;
946 				r_ctl = FC_RCTL_DD_CMD_STATUS;
947 				offset = 0;
948 			} else {
949 				QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS,
950 				    "READ - DATA lost.\n");
951 				/*
952 				 * For read case we always set the offset to 0
953 				 * for sequence recovery task.
954 				 */
955 				offset = 0;
956 				r_ctl = FC_RCTL_DD_SOL_DATA;
957 			}
958 		}
959 
960 		if (srr_needed)
961 			qedf_send_srr(orig_io_req, offset, r_ctl);
962 		else
963 			qedf_initiate_seq_cleanup(orig_io_req, offset, r_ctl);
964 	}
965 
966 out_free_frame:
967 	fc_frame_free(fp);
968 out_put:
969 	/* Put reference for original command since REC completed */
970 	kref_put(&orig_io_req->refcount, qedf_release_cmd);
971 out_free:
972 	kfree(cb_arg);
973 }
974 
975 /* Assumes kref is already held by caller */
976 int qedf_send_rec(struct qedf_ioreq *orig_io_req)
977 {
978 
979 	struct fc_els_rec rec;
980 	struct qedf_rport *fcport;
981 	struct fc_lport *lport;
982 	struct qedf_els_cb_arg *cb_arg = NULL;
983 	struct qedf_ctx *qedf;
984 	uint32_t sid;
985 	uint32_t r_a_tov;
986 	int rc;
987 
988 	if (!orig_io_req) {
989 		QEDF_ERR(NULL, "orig_io_req is NULL.\n");
990 		return -EINVAL;
991 	}
992 
993 	fcport = orig_io_req->fcport;
994 
995 	/* Check that fcport is still offloaded */
996 	if (!test_bit(QEDF_RPORT_SESSION_READY, &fcport->flags)) {
997 		QEDF_ERR(NULL, "fcport is no longer offloaded.\n");
998 		return -EINVAL;
999 	}
1000 
1001 	if (!fcport->qedf) {
1002 		QEDF_ERR(NULL, "fcport->qedf is NULL.\n");
1003 		return -EINVAL;
1004 	}
1005 
1006 	/* Take reference until REC command completion */
1007 	kref_get(&orig_io_req->refcount);
1008 
1009 	qedf = fcport->qedf;
1010 	lport = qedf->lport;
1011 	sid = fcport->sid;
1012 	r_a_tov = lport->r_a_tov;
1013 
1014 	memset(&rec, 0, sizeof(rec));
1015 
1016 	cb_arg = kzalloc(sizeof(struct qedf_els_cb_arg), GFP_NOIO);
1017 	if (!cb_arg) {
1018 		QEDF_ERR(&(qedf->dbg_ctx), "Unable to allocate cb_arg for "
1019 			  "REC\n");
1020 		rc = -ENOMEM;
1021 		goto rec_err;
1022 	}
1023 
1024 	cb_arg->aborted_io_req = orig_io_req;
1025 
1026 	rec.rec_cmd = ELS_REC;
1027 	hton24(rec.rec_s_id, sid);
1028 	rec.rec_ox_id = htons(orig_io_req->xid);
1029 	rec.rec_rx_id =
1030 	    htons(orig_io_req->task->tstorm_st_context.read_write.rx_id);
1031 
1032 	QEDF_INFO(&(qedf->dbg_ctx), QEDF_LOG_ELS, "Sending REC orig_io=%p, "
1033 	   "orig_xid=0x%x rx_id=0x%x\n", orig_io_req,
1034 	   orig_io_req->xid, rec.rec_rx_id);
1035 	rc = qedf_initiate_els(fcport, ELS_REC, &rec, sizeof(rec),
1036 	    qedf_rec_compl, cb_arg, r_a_tov);
1037 
1038 rec_err:
1039 	if (rc) {
1040 		QEDF_ERR(&(qedf->dbg_ctx), "REC failed - release orig_io_req"
1041 			  "=0x%x\n", orig_io_req->xid);
1042 		kfree(cb_arg);
1043 		kref_put(&orig_io_req->refcount, qedf_release_cmd);
1044 	}
1045 	return rc;
1046 }
1047