xref: /freebsd/sys/dev/nvme/nvme_qpair.c (revision 3e5645b78f476816ca3b5acc28b29bbafbb9c444)
1 /*-
2  * Copyright (C) 2012-2014 Intel Corporation
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <sys/param.h>
31 #include <sys/bus.h>
32 
33 #include <dev/pci/pcivar.h>
34 
35 #include "nvme_private.h"
36 
37 static void	_nvme_qpair_submit_request(struct nvme_qpair *qpair,
38 					   struct nvme_request *req);
39 
40 struct nvme_opcode_string {
41 
42 	uint16_t	opc;
43 	const char *	str;
44 };
45 
46 static struct nvme_opcode_string admin_opcode[] = {
47 	{ NVME_OPC_DELETE_IO_SQ, "DELETE IO SQ" },
48 	{ NVME_OPC_CREATE_IO_SQ, "CREATE IO SQ" },
49 	{ NVME_OPC_GET_LOG_PAGE, "GET LOG PAGE" },
50 	{ NVME_OPC_DELETE_IO_CQ, "DELETE IO CQ" },
51 	{ NVME_OPC_CREATE_IO_CQ, "CREATE IO CQ" },
52 	{ NVME_OPC_IDENTIFY, "IDENTIFY" },
53 	{ NVME_OPC_ABORT, "ABORT" },
54 	{ NVME_OPC_SET_FEATURES, "SET FEATURES" },
55 	{ NVME_OPC_GET_FEATURES, "GET FEATURES" },
56 	{ NVME_OPC_ASYNC_EVENT_REQUEST, "ASYNC EVENT REQUEST" },
57 	{ NVME_OPC_FIRMWARE_ACTIVATE, "FIRMWARE ACTIVATE" },
58 	{ NVME_OPC_FIRMWARE_IMAGE_DOWNLOAD, "FIRMWARE IMAGE DOWNLOAD" },
59 	{ NVME_OPC_FORMAT_NVM, "FORMAT NVM" },
60 	{ NVME_OPC_SECURITY_SEND, "SECURITY SEND" },
61 	{ NVME_OPC_SECURITY_RECEIVE, "SECURITY RECEIVE" },
62 	{ 0xFFFF, "ADMIN COMMAND" }
63 };
64 
65 static struct nvme_opcode_string io_opcode[] = {
66 	{ NVME_OPC_FLUSH, "FLUSH" },
67 	{ NVME_OPC_WRITE, "WRITE" },
68 	{ NVME_OPC_READ, "READ" },
69 	{ NVME_OPC_WRITE_UNCORRECTABLE, "WRITE UNCORRECTABLE" },
70 	{ NVME_OPC_COMPARE, "COMPARE" },
71 	{ NVME_OPC_DATASET_MANAGEMENT, "DATASET MANAGEMENT" },
72 	{ 0xFFFF, "IO COMMAND" }
73 };
74 
75 static const char *
76 get_admin_opcode_string(uint16_t opc)
77 {
78 	struct nvme_opcode_string *entry;
79 
80 	entry = admin_opcode;
81 
82 	while (entry->opc != 0xFFFF) {
83 		if (entry->opc == opc)
84 			return (entry->str);
85 		entry++;
86 	}
87 	return (entry->str);
88 }
89 
90 static const char *
91 get_io_opcode_string(uint16_t opc)
92 {
93 	struct nvme_opcode_string *entry;
94 
95 	entry = io_opcode;
96 
97 	while (entry->opc != 0xFFFF) {
98 		if (entry->opc == opc)
99 			return (entry->str);
100 		entry++;
101 	}
102 	return (entry->str);
103 }
104 
105 
106 static void
107 nvme_admin_qpair_print_command(struct nvme_qpair *qpair,
108     struct nvme_command *cmd)
109 {
110 
111 	nvme_printf(qpair->ctrlr, "%s (%02x) sqid:%d cid:%d nsid:%x "
112 	    "cdw10:%08x cdw11:%08x\n",
113 	    get_admin_opcode_string(cmd->opc), cmd->opc, qpair->id, cmd->cid,
114 	    cmd->nsid, cmd->cdw10, cmd->cdw11);
115 }
116 
117 static void
118 nvme_io_qpair_print_command(struct nvme_qpair *qpair,
119     struct nvme_command *cmd)
120 {
121 
122 	switch (cmd->opc) {
123 	case NVME_OPC_WRITE:
124 	case NVME_OPC_READ:
125 	case NVME_OPC_WRITE_UNCORRECTABLE:
126 	case NVME_OPC_COMPARE:
127 		nvme_printf(qpair->ctrlr, "%s sqid:%d cid:%d nsid:%d "
128 		    "lba:%llu len:%d\n",
129 		    get_io_opcode_string(cmd->opc), qpair->id, cmd->cid,
130 		    cmd->nsid,
131 		    ((unsigned long long)cmd->cdw11 << 32) + cmd->cdw10,
132 		    (cmd->cdw12 & 0xFFFF) + 1);
133 		break;
134 	case NVME_OPC_FLUSH:
135 	case NVME_OPC_DATASET_MANAGEMENT:
136 		nvme_printf(qpair->ctrlr, "%s sqid:%d cid:%d nsid:%d\n",
137 		    get_io_opcode_string(cmd->opc), qpair->id, cmd->cid,
138 		    cmd->nsid);
139 		break;
140 	default:
141 		nvme_printf(qpair->ctrlr, "%s (%02x) sqid:%d cid:%d nsid:%d\n",
142 		    get_io_opcode_string(cmd->opc), cmd->opc, qpair->id,
143 		    cmd->cid, cmd->nsid);
144 		break;
145 	}
146 }
147 
148 static void
149 nvme_qpair_print_command(struct nvme_qpair *qpair, struct nvme_command *cmd)
150 {
151 	if (qpair->id == 0)
152 		nvme_admin_qpair_print_command(qpair, cmd);
153 	else
154 		nvme_io_qpair_print_command(qpair, cmd);
155 }
156 
157 struct nvme_status_string {
158 
159 	uint16_t	sc;
160 	const char *	str;
161 };
162 
163 static struct nvme_status_string generic_status[] = {
164 	{ NVME_SC_SUCCESS, "SUCCESS" },
165 	{ NVME_SC_INVALID_OPCODE, "INVALID OPCODE" },
166 	{ NVME_SC_INVALID_FIELD, "INVALID_FIELD" },
167 	{ NVME_SC_COMMAND_ID_CONFLICT, "COMMAND ID CONFLICT" },
168 	{ NVME_SC_DATA_TRANSFER_ERROR, "DATA TRANSFER ERROR" },
169 	{ NVME_SC_ABORTED_POWER_LOSS, "ABORTED - POWER LOSS" },
170 	{ NVME_SC_INTERNAL_DEVICE_ERROR, "INTERNAL DEVICE ERROR" },
171 	{ NVME_SC_ABORTED_BY_REQUEST, "ABORTED - BY REQUEST" },
172 	{ NVME_SC_ABORTED_SQ_DELETION, "ABORTED - SQ DELETION" },
173 	{ NVME_SC_ABORTED_FAILED_FUSED, "ABORTED - FAILED FUSED" },
174 	{ NVME_SC_ABORTED_MISSING_FUSED, "ABORTED - MISSING FUSED" },
175 	{ NVME_SC_INVALID_NAMESPACE_OR_FORMAT, "INVALID NAMESPACE OR FORMAT" },
176 	{ NVME_SC_COMMAND_SEQUENCE_ERROR, "COMMAND SEQUENCE ERROR" },
177 	{ NVME_SC_LBA_OUT_OF_RANGE, "LBA OUT OF RANGE" },
178 	{ NVME_SC_CAPACITY_EXCEEDED, "CAPACITY EXCEEDED" },
179 	{ NVME_SC_NAMESPACE_NOT_READY, "NAMESPACE NOT READY" },
180 	{ 0xFFFF, "GENERIC" }
181 };
182 
183 static struct nvme_status_string command_specific_status[] = {
184 	{ NVME_SC_COMPLETION_QUEUE_INVALID, "INVALID COMPLETION QUEUE" },
185 	{ NVME_SC_INVALID_QUEUE_IDENTIFIER, "INVALID QUEUE IDENTIFIER" },
186 	{ NVME_SC_MAXIMUM_QUEUE_SIZE_EXCEEDED, "MAX QUEUE SIZE EXCEEDED" },
187 	{ NVME_SC_ABORT_COMMAND_LIMIT_EXCEEDED, "ABORT CMD LIMIT EXCEEDED" },
188 	{ NVME_SC_ASYNC_EVENT_REQUEST_LIMIT_EXCEEDED, "ASYNC LIMIT EXCEEDED" },
189 	{ NVME_SC_INVALID_FIRMWARE_SLOT, "INVALID FIRMWARE SLOT" },
190 	{ NVME_SC_INVALID_FIRMWARE_IMAGE, "INVALID FIRMWARE IMAGE" },
191 	{ NVME_SC_INVALID_INTERRUPT_VECTOR, "INVALID INTERRUPT VECTOR" },
192 	{ NVME_SC_INVALID_LOG_PAGE, "INVALID LOG PAGE" },
193 	{ NVME_SC_INVALID_FORMAT, "INVALID FORMAT" },
194 	{ NVME_SC_FIRMWARE_REQUIRES_RESET, "FIRMWARE REQUIRES RESET" },
195 	{ NVME_SC_CONFLICTING_ATTRIBUTES, "CONFLICTING ATTRIBUTES" },
196 	{ NVME_SC_INVALID_PROTECTION_INFO, "INVALID PROTECTION INFO" },
197 	{ NVME_SC_ATTEMPTED_WRITE_TO_RO_PAGE, "WRITE TO RO PAGE" },
198 	{ 0xFFFF, "COMMAND SPECIFIC" }
199 };
200 
201 static struct nvme_status_string media_error_status[] = {
202 	{ NVME_SC_WRITE_FAULTS, "WRITE FAULTS" },
203 	{ NVME_SC_UNRECOVERED_READ_ERROR, "UNRECOVERED READ ERROR" },
204 	{ NVME_SC_GUARD_CHECK_ERROR, "GUARD CHECK ERROR" },
205 	{ NVME_SC_APPLICATION_TAG_CHECK_ERROR, "APPLICATION TAG CHECK ERROR" },
206 	{ NVME_SC_REFERENCE_TAG_CHECK_ERROR, "REFERENCE TAG CHECK ERROR" },
207 	{ NVME_SC_COMPARE_FAILURE, "COMPARE FAILURE" },
208 	{ NVME_SC_ACCESS_DENIED, "ACCESS DENIED" },
209 	{ 0xFFFF, "MEDIA ERROR" }
210 };
211 
212 static const char *
213 get_status_string(uint16_t sct, uint16_t sc)
214 {
215 	struct nvme_status_string *entry;
216 
217 	switch (sct) {
218 	case NVME_SCT_GENERIC:
219 		entry = generic_status;
220 		break;
221 	case NVME_SCT_COMMAND_SPECIFIC:
222 		entry = command_specific_status;
223 		break;
224 	case NVME_SCT_MEDIA_ERROR:
225 		entry = media_error_status;
226 		break;
227 	case NVME_SCT_VENDOR_SPECIFIC:
228 		return ("VENDOR SPECIFIC");
229 	default:
230 		return ("RESERVED");
231 	}
232 
233 	while (entry->sc != 0xFFFF) {
234 		if (entry->sc == sc)
235 			return (entry->str);
236 		entry++;
237 	}
238 	return (entry->str);
239 }
240 
241 static void
242 nvme_qpair_print_completion(struct nvme_qpair *qpair,
243     struct nvme_completion *cpl)
244 {
245 	nvme_printf(qpair->ctrlr, "%s (%02x/%02x) sqid:%d cid:%d cdw0:%x\n",
246 	    get_status_string(cpl->status.sct, cpl->status.sc),
247 	    cpl->status.sct, cpl->status.sc, cpl->sqid, cpl->cid, cpl->cdw0);
248 }
249 
250 static boolean_t
251 nvme_completion_is_retry(const struct nvme_completion *cpl)
252 {
253 	/*
254 	 * TODO: spec is not clear how commands that are aborted due
255 	 *  to TLER will be marked.  So for now, it seems
256 	 *  NAMESPACE_NOT_READY is the only case where we should
257 	 *  look at the DNR bit.
258 	 */
259 	switch (cpl->status.sct) {
260 	case NVME_SCT_GENERIC:
261 		switch (cpl->status.sc) {
262 		case NVME_SC_ABORTED_BY_REQUEST:
263 		case NVME_SC_NAMESPACE_NOT_READY:
264 			if (cpl->status.dnr)
265 				return (0);
266 			else
267 				return (1);
268 		case NVME_SC_INVALID_OPCODE:
269 		case NVME_SC_INVALID_FIELD:
270 		case NVME_SC_COMMAND_ID_CONFLICT:
271 		case NVME_SC_DATA_TRANSFER_ERROR:
272 		case NVME_SC_ABORTED_POWER_LOSS:
273 		case NVME_SC_INTERNAL_DEVICE_ERROR:
274 		case NVME_SC_ABORTED_SQ_DELETION:
275 		case NVME_SC_ABORTED_FAILED_FUSED:
276 		case NVME_SC_ABORTED_MISSING_FUSED:
277 		case NVME_SC_INVALID_NAMESPACE_OR_FORMAT:
278 		case NVME_SC_COMMAND_SEQUENCE_ERROR:
279 		case NVME_SC_LBA_OUT_OF_RANGE:
280 		case NVME_SC_CAPACITY_EXCEEDED:
281 		default:
282 			return (0);
283 		}
284 	case NVME_SCT_COMMAND_SPECIFIC:
285 	case NVME_SCT_MEDIA_ERROR:
286 	case NVME_SCT_VENDOR_SPECIFIC:
287 	default:
288 		return (0);
289 	}
290 }
291 
292 static void
293 nvme_qpair_construct_tracker(struct nvme_qpair *qpair, struct nvme_tracker *tr,
294     uint16_t cid)
295 {
296 
297 	bus_dmamap_create(qpair->dma_tag_payload, 0, &tr->payload_dma_map);
298 	bus_dmamap_create(qpair->dma_tag, 0, &tr->prp_dma_map);
299 
300 	bus_dmamap_load(qpair->dma_tag, tr->prp_dma_map, tr->prp,
301 	    sizeof(tr->prp), nvme_single_map, &tr->prp_bus_addr, 0);
302 
303 	callout_init(&tr->timer, 1);
304 	tr->cid = cid;
305 	tr->qpair = qpair;
306 }
307 
308 static void
309 nvme_qpair_complete_tracker(struct nvme_qpair *qpair, struct nvme_tracker *tr,
310     struct nvme_completion *cpl, boolean_t print_on_error)
311 {
312 	struct nvme_request	*req;
313 	boolean_t		retry, error;
314 
315 	req = tr->req;
316 	error = nvme_completion_is_error(cpl);
317 	retry = error && nvme_completion_is_retry(cpl) &&
318 	   req->retries < nvme_retry_count;
319 
320 	if (error && print_on_error) {
321 		nvme_qpair_print_command(qpair, &req->cmd);
322 		nvme_qpair_print_completion(qpair, cpl);
323 	}
324 
325 	qpair->act_tr[cpl->cid] = NULL;
326 
327 	KASSERT(cpl->cid == req->cmd.cid, ("cpl cid does not match cmd cid\n"));
328 
329 	if (req->cb_fn && !retry)
330 		req->cb_fn(req->cb_arg, cpl);
331 
332 	mtx_lock(&qpair->lock);
333 	callout_stop(&tr->timer);
334 
335 	if (retry) {
336 		req->retries++;
337 		nvme_qpair_submit_tracker(qpair, tr);
338 	} else {
339 		if (req->type != NVME_REQUEST_NULL)
340 			bus_dmamap_unload(qpair->dma_tag_payload,
341 			    tr->payload_dma_map);
342 
343 		nvme_free_request(req);
344 		tr->req = NULL;
345 
346 		TAILQ_REMOVE(&qpair->outstanding_tr, tr, tailq);
347 		TAILQ_INSERT_HEAD(&qpair->free_tr, tr, tailq);
348 
349 		/*
350 		 * If the controller is in the middle of resetting, don't
351 		 *  try to submit queued requests here - let the reset logic
352 		 *  handle that instead.
353 		 */
354 		if (!STAILQ_EMPTY(&qpair->queued_req) &&
355 		    !qpair->ctrlr->is_resetting) {
356 			req = STAILQ_FIRST(&qpair->queued_req);
357 			STAILQ_REMOVE_HEAD(&qpair->queued_req, stailq);
358 			_nvme_qpair_submit_request(qpair, req);
359 		}
360 	}
361 
362 	mtx_unlock(&qpair->lock);
363 }
364 
365 static void
366 nvme_qpair_manual_complete_tracker(struct nvme_qpair *qpair,
367     struct nvme_tracker *tr, uint32_t sct, uint32_t sc, uint32_t dnr,
368     boolean_t print_on_error)
369 {
370 	struct nvme_completion	cpl;
371 
372 	memset(&cpl, 0, sizeof(cpl));
373 	cpl.sqid = qpair->id;
374 	cpl.cid = tr->cid;
375 	cpl.status.sct = sct;
376 	cpl.status.sc = sc;
377 	cpl.status.dnr = dnr;
378 	nvme_qpair_complete_tracker(qpair, tr, &cpl, print_on_error);
379 }
380 
381 void
382 nvme_qpair_manual_complete_request(struct nvme_qpair *qpair,
383     struct nvme_request *req, uint32_t sct, uint32_t sc,
384     boolean_t print_on_error)
385 {
386 	struct nvme_completion	cpl;
387 	boolean_t		error;
388 
389 	memset(&cpl, 0, sizeof(cpl));
390 	cpl.sqid = qpair->id;
391 	cpl.status.sct = sct;
392 	cpl.status.sc = sc;
393 
394 	error = nvme_completion_is_error(&cpl);
395 
396 	if (error && print_on_error) {
397 		nvme_qpair_print_command(qpair, &req->cmd);
398 		nvme_qpair_print_completion(qpair, &cpl);
399 	}
400 
401 	if (req->cb_fn)
402 		req->cb_fn(req->cb_arg, &cpl);
403 
404 	nvme_free_request(req);
405 }
406 
407 void
408 nvme_qpair_process_completions(struct nvme_qpair *qpair)
409 {
410 	struct nvme_tracker	*tr;
411 	struct nvme_completion	*cpl;
412 
413 	qpair->num_intr_handler_calls++;
414 
415 	if (!qpair->is_enabled)
416 		/*
417 		 * qpair is not enabled, likely because a controller reset is
418 		 *  is in progress.  Ignore the interrupt - any I/O that was
419 		 *  associated with this interrupt will get retried when the
420 		 *  reset is complete.
421 		 */
422 		return;
423 
424 	while (1) {
425 		cpl = &qpair->cpl[qpair->cq_head];
426 
427 		if (cpl->status.p != qpair->phase)
428 			break;
429 
430 		tr = qpair->act_tr[cpl->cid];
431 
432 		if (tr != NULL) {
433 			nvme_qpair_complete_tracker(qpair, tr, cpl, TRUE);
434 			qpair->sq_head = cpl->sqhd;
435 		} else {
436 			nvme_printf(qpair->ctrlr,
437 			    "cpl does not map to outstanding cmd\n");
438 			nvme_dump_completion(cpl);
439 			KASSERT(0, ("received completion for unknown cmd\n"));
440 		}
441 
442 		if (++qpair->cq_head == qpair->num_entries) {
443 			qpair->cq_head = 0;
444 			qpair->phase = !qpair->phase;
445 		}
446 
447 		nvme_mmio_write_4(qpair->ctrlr, doorbell[qpair->id].cq_hdbl,
448 		    qpair->cq_head);
449 	}
450 }
451 
452 static void
453 nvme_qpair_msix_handler(void *arg)
454 {
455 	struct nvme_qpair *qpair = arg;
456 
457 	nvme_qpair_process_completions(qpair);
458 }
459 
460 void
461 nvme_qpair_construct(struct nvme_qpair *qpair, uint32_t id,
462     uint16_t vector, uint32_t num_entries, uint32_t num_trackers,
463     struct nvme_controller *ctrlr)
464 {
465 	struct nvme_tracker	*tr;
466 	uint32_t		i;
467 	int			err;
468 
469 	qpair->id = id;
470 	qpair->vector = vector;
471 	qpair->num_entries = num_entries;
472 	qpair->num_trackers = num_trackers;
473 	qpair->ctrlr = ctrlr;
474 
475 	if (ctrlr->msix_enabled) {
476 
477 		/*
478 		 * MSI-X vector resource IDs start at 1, so we add one to
479 		 *  the queue's vector to get the corresponding rid to use.
480 		 */
481 		qpair->rid = vector + 1;
482 		qpair->res = ctrlr->msi_res[vector];
483 
484 		bus_setup_intr(ctrlr->dev, qpair->res,
485 		    INTR_TYPE_MISC | INTR_MPSAFE, NULL,
486 		    nvme_qpair_msix_handler, qpair, &qpair->tag);
487 	}
488 
489 	mtx_init(&qpair->lock, "nvme qpair lock", NULL, MTX_DEF);
490 
491 	/* Note: NVMe PRP format is restricted to 4-byte alignment. */
492 	err = bus_dma_tag_create(bus_get_dma_tag(ctrlr->dev),
493 	    4, PAGE_SIZE, BUS_SPACE_MAXADDR,
494 	    BUS_SPACE_MAXADDR, NULL, NULL, NVME_MAX_XFER_SIZE,
495 	    (NVME_MAX_XFER_SIZE/PAGE_SIZE)+1, PAGE_SIZE, 0,
496 	    NULL, NULL, &qpair->dma_tag_payload);
497 	if (err != 0)
498 		nvme_printf(ctrlr, "payload tag create failed %d\n", err);
499 
500 	err = bus_dma_tag_create(bus_get_dma_tag(ctrlr->dev),
501 	    4, 0, BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
502 	    BUS_SPACE_MAXSIZE, 1, BUS_SPACE_MAXSIZE, 0,
503 	    NULL, NULL, &qpair->dma_tag);
504 	if (err != 0)
505 		nvme_printf(ctrlr, "tag create failed %d\n", err);
506 
507 	qpair->num_cmds = 0;
508 	qpair->num_intr_handler_calls = 0;
509 
510 	qpair->cmd = contigmalloc(qpair->num_entries *
511 	    sizeof(struct nvme_command), M_NVME, M_ZERO,
512 	    0, BUS_SPACE_MAXADDR, PAGE_SIZE, 0);
513 	qpair->cpl = contigmalloc(qpair->num_entries *
514 	    sizeof(struct nvme_completion), M_NVME, M_ZERO,
515 	    0, BUS_SPACE_MAXADDR, PAGE_SIZE, 0);
516 
517 	err = bus_dmamap_create(qpair->dma_tag, 0, &qpair->cmd_dma_map);
518 	if (err != 0)
519 		nvme_printf(ctrlr, "cmd_dma_map create failed %d\n", err);
520 
521 	err = bus_dmamap_create(qpair->dma_tag, 0, &qpair->cpl_dma_map);
522 	if (err != 0)
523 		nvme_printf(ctrlr, "cpl_dma_map create failed %d\n", err);
524 
525 	bus_dmamap_load(qpair->dma_tag, qpair->cmd_dma_map,
526 	    qpair->cmd, qpair->num_entries * sizeof(struct nvme_command),
527 	    nvme_single_map, &qpair->cmd_bus_addr, 0);
528 	bus_dmamap_load(qpair->dma_tag, qpair->cpl_dma_map,
529 	    qpair->cpl, qpair->num_entries * sizeof(struct nvme_completion),
530 	    nvme_single_map, &qpair->cpl_bus_addr, 0);
531 
532 	qpair->sq_tdbl_off = nvme_mmio_offsetof(doorbell[id].sq_tdbl);
533 	qpair->cq_hdbl_off = nvme_mmio_offsetof(doorbell[id].cq_hdbl);
534 
535 	TAILQ_INIT(&qpair->free_tr);
536 	TAILQ_INIT(&qpair->outstanding_tr);
537 	STAILQ_INIT(&qpair->queued_req);
538 
539 	for (i = 0; i < qpair->num_trackers; i++) {
540 		tr = malloc(sizeof(*tr), M_NVME, M_ZERO | M_WAITOK);
541 		nvme_qpair_construct_tracker(qpair, tr, i);
542 		TAILQ_INSERT_HEAD(&qpair->free_tr, tr, tailq);
543 	}
544 
545 	qpair->act_tr = malloc(sizeof(struct nvme_tracker *) * qpair->num_entries,
546 	    M_NVME, M_ZERO | M_WAITOK);
547 }
548 
549 static void
550 nvme_qpair_destroy(struct nvme_qpair *qpair)
551 {
552 	struct nvme_tracker	*tr;
553 
554 	if (qpair->tag)
555 		bus_teardown_intr(qpair->ctrlr->dev, qpair->res, qpair->tag);
556 
557 	if (qpair->res)
558 		bus_release_resource(qpair->ctrlr->dev, SYS_RES_IRQ,
559 		    rman_get_rid(qpair->res), qpair->res);
560 
561 	if (qpair->cmd) {
562 		bus_dmamap_unload(qpair->dma_tag, qpair->cmd_dma_map);
563 		bus_dmamap_destroy(qpair->dma_tag, qpair->cmd_dma_map);
564 		contigfree(qpair->cmd,
565 		    qpair->num_entries * sizeof(struct nvme_command), M_NVME);
566 	}
567 
568 	if (qpair->cpl) {
569 		bus_dmamap_unload(qpair->dma_tag, qpair->cpl_dma_map);
570 		bus_dmamap_destroy(qpair->dma_tag, qpair->cpl_dma_map);
571 		contigfree(qpair->cpl,
572 		    qpair->num_entries * sizeof(struct nvme_completion),
573 		    M_NVME);
574 	}
575 
576 	if (qpair->dma_tag)
577 		bus_dma_tag_destroy(qpair->dma_tag);
578 
579 	if (qpair->dma_tag_payload)
580 		bus_dma_tag_destroy(qpair->dma_tag_payload);
581 
582 	if (qpair->act_tr)
583 		free(qpair->act_tr, M_NVME);
584 
585 	while (!TAILQ_EMPTY(&qpair->free_tr)) {
586 		tr = TAILQ_FIRST(&qpair->free_tr);
587 		TAILQ_REMOVE(&qpair->free_tr, tr, tailq);
588 		bus_dmamap_destroy(qpair->dma_tag, tr->payload_dma_map);
589 		bus_dmamap_destroy(qpair->dma_tag, tr->prp_dma_map);
590 		free(tr, M_NVME);
591 	}
592 }
593 
594 static void
595 nvme_admin_qpair_abort_aers(struct nvme_qpair *qpair)
596 {
597 	struct nvme_tracker	*tr;
598 
599 	tr = TAILQ_FIRST(&qpair->outstanding_tr);
600 	while (tr != NULL) {
601 		if (tr->req->cmd.opc == NVME_OPC_ASYNC_EVENT_REQUEST) {
602 			nvme_qpair_manual_complete_tracker(qpair, tr,
603 			    NVME_SCT_GENERIC, NVME_SC_ABORTED_SQ_DELETION, 0,
604 			    FALSE);
605 			tr = TAILQ_FIRST(&qpair->outstanding_tr);
606 		} else {
607 			tr = TAILQ_NEXT(tr, tailq);
608 		}
609 	}
610 }
611 
612 void
613 nvme_admin_qpair_destroy(struct nvme_qpair *qpair)
614 {
615 
616 	nvme_admin_qpair_abort_aers(qpair);
617 	nvme_qpair_destroy(qpair);
618 }
619 
620 void
621 nvme_io_qpair_destroy(struct nvme_qpair *qpair)
622 {
623 
624 	nvme_qpair_destroy(qpair);
625 }
626 
627 static void
628 nvme_abort_complete(void *arg, const struct nvme_completion *status)
629 {
630 	struct nvme_tracker	*tr = arg;
631 
632 	/*
633 	 * If cdw0 == 1, the controller was not able to abort the command
634 	 *  we requested.  We still need to check the active tracker array,
635 	 *  to cover race where I/O timed out at same time controller was
636 	 *  completing the I/O.
637 	 */
638 	if (status->cdw0 == 1 && tr->qpair->act_tr[tr->cid] != NULL) {
639 		/*
640 		 * An I/O has timed out, and the controller was unable to
641 		 *  abort it for some reason.  Construct a fake completion
642 		 *  status, and then complete the I/O's tracker manually.
643 		 */
644 		nvme_printf(tr->qpair->ctrlr,
645 		    "abort command failed, aborting command manually\n");
646 		nvme_qpair_manual_complete_tracker(tr->qpair, tr,
647 		    NVME_SCT_GENERIC, NVME_SC_ABORTED_BY_REQUEST, 0, TRUE);
648 	}
649 }
650 
651 static void
652 nvme_timeout(void *arg)
653 {
654 	struct nvme_tracker	*tr = arg;
655 	struct nvme_qpair	*qpair = tr->qpair;
656 	struct nvme_controller	*ctrlr = qpair->ctrlr;
657 	union csts_register	csts;
658 
659 	/* Read csts to get value of cfs - controller fatal status. */
660 	csts.raw = nvme_mmio_read_4(ctrlr, csts);
661 
662 	if (ctrlr->enable_aborts && csts.bits.cfs == 0) {
663 		/*
664 		 * If aborts are enabled, only use them if the controller is
665 		 *  not reporting fatal status.
666 		 */
667 		nvme_ctrlr_cmd_abort(ctrlr, tr->cid, qpair->id,
668 		    nvme_abort_complete, tr);
669 	} else
670 		nvme_ctrlr_reset(ctrlr);
671 }
672 
673 void
674 nvme_qpair_submit_tracker(struct nvme_qpair *qpair, struct nvme_tracker *tr)
675 {
676 	struct nvme_request	*req;
677 	struct nvme_controller	*ctrlr;
678 
679 	mtx_assert(&qpair->lock, MA_OWNED);
680 
681 	req = tr->req;
682 	req->cmd.cid = tr->cid;
683 	qpair->act_tr[tr->cid] = tr;
684 	ctrlr = qpair->ctrlr;
685 
686 	if (req->timeout)
687 #if __FreeBSD_version >= 800030
688 		callout_reset_curcpu(&tr->timer, ctrlr->timeout_period * hz,
689 		    nvme_timeout, tr);
690 #else
691 		callout_reset(&tr->timer, ctrlr->timeout_period * hz,
692 		    nvme_timeout, tr);
693 #endif
694 
695 	/* Copy the command from the tracker to the submission queue. */
696 	memcpy(&qpair->cmd[qpair->sq_tail], &req->cmd, sizeof(req->cmd));
697 
698 	if (++qpair->sq_tail == qpair->num_entries)
699 		qpair->sq_tail = 0;
700 
701 	wmb();
702 	nvme_mmio_write_4(qpair->ctrlr, doorbell[qpair->id].sq_tdbl,
703 	    qpair->sq_tail);
704 
705 	qpair->num_cmds++;
706 }
707 
708 static void
709 nvme_payload_map(void *arg, bus_dma_segment_t *seg, int nseg, int error)
710 {
711 	struct nvme_tracker 	*tr = arg;
712 	uint32_t		cur_nseg;
713 
714 	/*
715 	 * If the mapping operation failed, return immediately.  The caller
716 	 *  is responsible for detecting the error status and failing the
717 	 *  tracker manually.
718 	 */
719 	if (error != 0) {
720 		nvme_printf(tr->qpair->ctrlr,
721 		    "nvme_payload_map err %d\n", error);
722 		return;
723 	}
724 
725 	/*
726 	 * Note that we specified PAGE_SIZE for alignment and max
727 	 *  segment size when creating the bus dma tags.  So here
728 	 *  we can safely just transfer each segment to its
729 	 *  associated PRP entry.
730 	 */
731 	tr->req->cmd.prp1 = seg[0].ds_addr;
732 
733 	if (nseg == 2) {
734 		tr->req->cmd.prp2 = seg[1].ds_addr;
735 	} else if (nseg > 2) {
736 		cur_nseg = 1;
737 		tr->req->cmd.prp2 = (uint64_t)tr->prp_bus_addr;
738 		while (cur_nseg < nseg) {
739 			tr->prp[cur_nseg-1] =
740 			    (uint64_t)seg[cur_nseg].ds_addr;
741 			cur_nseg++;
742 		}
743 	} else {
744 		/*
745 		 * prp2 should not be used by the controller
746 		 *  since there is only one segment, but set
747 		 *  to 0 just to be safe.
748 		 */
749 		tr->req->cmd.prp2 = 0;
750 	}
751 
752 	nvme_qpair_submit_tracker(tr->qpair, tr);
753 }
754 
755 static void
756 _nvme_qpair_submit_request(struct nvme_qpair *qpair, struct nvme_request *req)
757 {
758 	struct nvme_tracker	*tr;
759 	int			err = 0;
760 
761 	mtx_assert(&qpair->lock, MA_OWNED);
762 
763 	tr = TAILQ_FIRST(&qpair->free_tr);
764 	req->qpair = qpair;
765 
766 	if (tr == NULL || !qpair->is_enabled) {
767 		/*
768 		 * No tracker is available, or the qpair is disabled due to
769 		 *  an in-progress controller-level reset or controller
770 		 *  failure.
771 		 */
772 
773 		if (qpair->ctrlr->is_failed) {
774 			/*
775 			 * The controller has failed.  Post the request to a
776 			 *  task where it will be aborted, so that we do not
777 			 *  invoke the request's callback in the context
778 			 *  of the submission.
779 			 */
780 			nvme_ctrlr_post_failed_request(qpair->ctrlr, req);
781 		} else {
782 			/*
783 			 * Put the request on the qpair's request queue to be
784 			 *  processed when a tracker frees up via a command
785 			 *  completion or when the controller reset is
786 			 *  completed.
787 			 */
788 			STAILQ_INSERT_TAIL(&qpair->queued_req, req, stailq);
789 		}
790 		return;
791 	}
792 
793 	TAILQ_REMOVE(&qpair->free_tr, tr, tailq);
794 	TAILQ_INSERT_TAIL(&qpair->outstanding_tr, tr, tailq);
795 	tr->req = req;
796 
797 	switch (req->type) {
798 	case NVME_REQUEST_VADDR:
799 		KASSERT(req->payload_size <= qpair->ctrlr->max_xfer_size,
800 		    ("payload_size (%d) exceeds max_xfer_size (%d)\n",
801 		    req->payload_size, qpair->ctrlr->max_xfer_size));
802 		err = bus_dmamap_load(tr->qpair->dma_tag_payload,
803 		    tr->payload_dma_map, req->u.payload, req->payload_size,
804 		    nvme_payload_map, tr, 0);
805 		if (err != 0)
806 			nvme_printf(qpair->ctrlr,
807 			    "bus_dmamap_load returned 0x%x!\n", err);
808 		break;
809 	case NVME_REQUEST_NULL:
810 		nvme_qpair_submit_tracker(tr->qpair, tr);
811 		break;
812 #ifdef NVME_UNMAPPED_BIO_SUPPORT
813 	case NVME_REQUEST_BIO:
814 		KASSERT(req->u.bio->bio_bcount <= qpair->ctrlr->max_xfer_size,
815 		    ("bio->bio_bcount (%jd) exceeds max_xfer_size (%d)\n",
816 		    (intmax_t)req->u.bio->bio_bcount,
817 		    qpair->ctrlr->max_xfer_size));
818 		err = bus_dmamap_load_bio(tr->qpair->dma_tag_payload,
819 		    tr->payload_dma_map, req->u.bio, nvme_payload_map, tr, 0);
820 		if (err != 0)
821 			nvme_printf(qpair->ctrlr,
822 			    "bus_dmamap_load_bio returned 0x%x!\n", err);
823 		break;
824 #endif
825 	default:
826 		panic("unknown nvme request type 0x%x\n", req->type);
827 		break;
828 	}
829 
830 	if (err != 0) {
831 		/*
832 		 * The dmamap operation failed, so we manually fail the
833 		 *  tracker here with DATA_TRANSFER_ERROR status.
834 		 *
835 		 * nvme_qpair_manual_complete_tracker must not be called
836 		 *  with the qpair lock held.
837 		 */
838 		mtx_unlock(&qpair->lock);
839 		nvme_qpair_manual_complete_tracker(qpair, tr, NVME_SCT_GENERIC,
840 		    NVME_SC_DATA_TRANSFER_ERROR, 1 /* do not retry */, TRUE);
841 		mtx_lock(&qpair->lock);
842 	}
843 }
844 
845 void
846 nvme_qpair_submit_request(struct nvme_qpair *qpair, struct nvme_request *req)
847 {
848 
849 	mtx_lock(&qpair->lock);
850 	_nvme_qpair_submit_request(qpair, req);
851 	mtx_unlock(&qpair->lock);
852 }
853 
854 static void
855 nvme_qpair_enable(struct nvme_qpair *qpair)
856 {
857 
858 	qpair->is_enabled = TRUE;
859 }
860 
861 void
862 nvme_qpair_reset(struct nvme_qpair *qpair)
863 {
864 
865 	qpair->sq_head = qpair->sq_tail = qpair->cq_head = 0;
866 
867 	/*
868 	 * First time through the completion queue, HW will set phase
869 	 *  bit on completions to 1.  So set this to 1 here, indicating
870 	 *  we're looking for a 1 to know which entries have completed.
871 	 *  we'll toggle the bit each time when the completion queue
872 	 *  rolls over.
873 	 */
874 	qpair->phase = 1;
875 
876 	memset(qpair->cmd, 0,
877 	    qpair->num_entries * sizeof(struct nvme_command));
878 	memset(qpair->cpl, 0,
879 	    qpair->num_entries * sizeof(struct nvme_completion));
880 }
881 
882 void
883 nvme_admin_qpair_enable(struct nvme_qpair *qpair)
884 {
885 	struct nvme_tracker		*tr;
886 	struct nvme_tracker		*tr_temp;
887 
888 	/*
889 	 * Manually abort each outstanding admin command.  Do not retry
890 	 *  admin commands found here, since they will be left over from
891 	 *  a controller reset and its likely the context in which the
892 	 *  command was issued no longer applies.
893 	 */
894 	TAILQ_FOREACH_SAFE(tr, &qpair->outstanding_tr, tailq, tr_temp) {
895 		nvme_printf(qpair->ctrlr,
896 		    "aborting outstanding admin command\n");
897 		nvme_qpair_manual_complete_tracker(qpair, tr, NVME_SCT_GENERIC,
898 		    NVME_SC_ABORTED_BY_REQUEST, 1 /* do not retry */, TRUE);
899 	}
900 
901 	nvme_qpair_enable(qpair);
902 }
903 
904 void
905 nvme_io_qpair_enable(struct nvme_qpair *qpair)
906 {
907 	STAILQ_HEAD(, nvme_request)	temp;
908 	struct nvme_tracker		*tr;
909 	struct nvme_tracker		*tr_temp;
910 	struct nvme_request		*req;
911 
912 	/*
913 	 * Manually abort each outstanding I/O.  This normally results in a
914 	 *  retry, unless the retry count on the associated request has
915 	 *  reached its limit.
916 	 */
917 	TAILQ_FOREACH_SAFE(tr, &qpair->outstanding_tr, tailq, tr_temp) {
918 		nvme_printf(qpair->ctrlr, "aborting outstanding i/o\n");
919 		nvme_qpair_manual_complete_tracker(qpair, tr, NVME_SCT_GENERIC,
920 		    NVME_SC_ABORTED_BY_REQUEST, 0, TRUE);
921 	}
922 
923 	mtx_lock(&qpair->lock);
924 
925 	nvme_qpair_enable(qpair);
926 
927 	STAILQ_INIT(&temp);
928 	STAILQ_SWAP(&qpair->queued_req, &temp, nvme_request);
929 
930 	while (!STAILQ_EMPTY(&temp)) {
931 		req = STAILQ_FIRST(&temp);
932 		STAILQ_REMOVE_HEAD(&temp, stailq);
933 		nvme_printf(qpair->ctrlr, "resubmitting queued i/o\n");
934 		nvme_qpair_print_command(qpair, &req->cmd);
935 		_nvme_qpair_submit_request(qpair, req);
936 	}
937 
938 	mtx_unlock(&qpair->lock);
939 }
940 
941 static void
942 nvme_qpair_disable(struct nvme_qpair *qpair)
943 {
944 	struct nvme_tracker *tr;
945 
946 	qpair->is_enabled = FALSE;
947 	mtx_lock(&qpair->lock);
948 	TAILQ_FOREACH(tr, &qpair->outstanding_tr, tailq)
949 		callout_stop(&tr->timer);
950 	mtx_unlock(&qpair->lock);
951 }
952 
953 void
954 nvme_admin_qpair_disable(struct nvme_qpair *qpair)
955 {
956 
957 	nvme_qpair_disable(qpair);
958 	nvme_admin_qpair_abort_aers(qpair);
959 }
960 
961 void
962 nvme_io_qpair_disable(struct nvme_qpair *qpair)
963 {
964 
965 	nvme_qpair_disable(qpair);
966 }
967 
968 void
969 nvme_qpair_fail(struct nvme_qpair *qpair)
970 {
971 	struct nvme_tracker		*tr;
972 	struct nvme_request		*req;
973 
974 	mtx_lock(&qpair->lock);
975 
976 	while (!STAILQ_EMPTY(&qpair->queued_req)) {
977 		req = STAILQ_FIRST(&qpair->queued_req);
978 		STAILQ_REMOVE_HEAD(&qpair->queued_req, stailq);
979 		nvme_printf(qpair->ctrlr, "failing queued i/o\n");
980 		mtx_unlock(&qpair->lock);
981 		nvme_qpair_manual_complete_request(qpair, req, NVME_SCT_GENERIC,
982 		    NVME_SC_ABORTED_BY_REQUEST, TRUE);
983 		mtx_lock(&qpair->lock);
984 	}
985 
986 	/* Manually abort each outstanding I/O. */
987 	while (!TAILQ_EMPTY(&qpair->outstanding_tr)) {
988 		tr = TAILQ_FIRST(&qpair->outstanding_tr);
989 		/*
990 		 * Do not remove the tracker.  The abort_tracker path will
991 		 *  do that for us.
992 		 */
993 		nvme_printf(qpair->ctrlr, "failing outstanding i/o\n");
994 		mtx_unlock(&qpair->lock);
995 		nvme_qpair_manual_complete_tracker(qpair, tr, NVME_SCT_GENERIC,
996 		    NVME_SC_ABORTED_BY_REQUEST, 1 /* do not retry */, TRUE);
997 		mtx_lock(&qpair->lock);
998 	}
999 
1000 	mtx_unlock(&qpair->lock);
1001 }
1002 
1003