xref: /freebsd/sys/dev/nvme/nvme_ctrlr.c (revision 2f9966ff63d65bd474478888c9088eeae3f9c669)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (C) 2012-2016 Intel Corporation
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include "opt_nvme.h"
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/buf.h>
34 #include <sys/bus.h>
35 #include <sys/conf.h>
36 #include <sys/ioccom.h>
37 #include <sys/proc.h>
38 #include <sys/smp.h>
39 #include <sys/uio.h>
40 #include <sys/sbuf.h>
41 #include <sys/endian.h>
42 #include <machine/stdarg.h>
43 #include <vm/vm.h>
44 
45 #include "nvme_private.h"
46 
47 #define B4_CHK_RDY_DELAY_MS	2300		/* work around controller bug */
48 
49 static void nvme_ctrlr_construct_and_submit_aer(struct nvme_controller *ctrlr,
50 						struct nvme_async_event_request *aer);
51 
52 static void
53 nvme_ctrlr_barrier(struct nvme_controller *ctrlr, int flags)
54 {
55 	bus_barrier(ctrlr->resource, 0, rman_get_size(ctrlr->resource), flags);
56 }
57 
58 static void
59 nvme_ctrlr_devctl_va(struct nvme_controller *ctrlr, const char *type,
60     const char *msg, va_list ap)
61 {
62 	struct sbuf sb;
63 	int error;
64 
65 	if (sbuf_new(&sb, NULL, 0, SBUF_AUTOEXTEND | SBUF_NOWAIT) == NULL)
66 		return;
67 	sbuf_printf(&sb, "name=\"%s\" ", device_get_nameunit(ctrlr->dev));
68 	sbuf_vprintf(&sb, msg, ap);
69 	error = sbuf_finish(&sb);
70 	if (error == 0)
71 		devctl_notify("nvme", "controller", type, sbuf_data(&sb));
72 	sbuf_delete(&sb);
73 }
74 
75 static void
76 nvme_ctrlr_devctl(struct nvme_controller *ctrlr, const char *type, const char *msg, ...)
77 {
78 	va_list ap;
79 
80 	va_start(ap, msg);
81 	nvme_ctrlr_devctl_va(ctrlr, type, msg, ap);
82 	va_end(ap);
83 }
84 
85 static void
86 nvme_ctrlr_devctl_log(struct nvme_controller *ctrlr, const char *type, const char *msg, ...)
87 {
88 	struct sbuf sb;
89 	va_list ap;
90 	int error;
91 
92 	if (sbuf_new(&sb, NULL, 0, SBUF_AUTOEXTEND | SBUF_NOWAIT) == NULL)
93 		return;
94 	sbuf_printf(&sb, "%s: ", device_get_nameunit(ctrlr->dev));
95 	va_start(ap, msg);
96 	sbuf_vprintf(&sb, msg, ap);
97 	va_end(ap);
98 	error = sbuf_finish(&sb);
99 	if (error == 0)
100 		printf("%s\n", sbuf_data(&sb));
101 	sbuf_delete(&sb);
102 	va_start(ap, msg);
103 	nvme_ctrlr_devctl_va(ctrlr, type, msg, ap);
104 	va_end(ap);
105 }
106 
107 static int
108 nvme_ctrlr_construct_admin_qpair(struct nvme_controller *ctrlr)
109 {
110 	struct nvme_qpair	*qpair;
111 	uint32_t		num_entries;
112 	int			error;
113 
114 	qpair = &ctrlr->adminq;
115 	qpair->id = 0;
116 	qpair->cpu = CPU_FFS(&cpuset_domain[ctrlr->domain]) - 1;
117 	qpair->domain = ctrlr->domain;
118 
119 	num_entries = NVME_ADMIN_ENTRIES;
120 	TUNABLE_INT_FETCH("hw.nvme.admin_entries", &num_entries);
121 	/*
122 	 * If admin_entries was overridden to an invalid value, revert it
123 	 *  back to our default value.
124 	 */
125 	if (num_entries < NVME_MIN_ADMIN_ENTRIES ||
126 	    num_entries > NVME_MAX_ADMIN_ENTRIES) {
127 		nvme_printf(ctrlr, "invalid hw.nvme.admin_entries=%d "
128 		    "specified\n", num_entries);
129 		num_entries = NVME_ADMIN_ENTRIES;
130 	}
131 
132 	/*
133 	 * The admin queue's max xfer size is treated differently than the
134 	 *  max I/O xfer size.  16KB is sufficient here - maybe even less?
135 	 */
136 	error = nvme_qpair_construct(qpair, num_entries, NVME_ADMIN_TRACKERS,
137 	     ctrlr);
138 	return (error);
139 }
140 
141 #define QP(ctrlr, c)	((c) * (ctrlr)->num_io_queues / mp_ncpus)
142 
143 static int
144 nvme_ctrlr_construct_io_qpairs(struct nvme_controller *ctrlr)
145 {
146 	struct nvme_qpair	*qpair;
147 	uint32_t		cap_lo;
148 	uint16_t		mqes;
149 	int			c, error, i, n;
150 	int			num_entries, num_trackers, max_entries;
151 
152 	/*
153 	 * NVMe spec sets a hard limit of 64K max entries, but devices may
154 	 * specify a smaller limit, so we need to check the MQES field in the
155 	 * capabilities register. We have to cap the number of entries to the
156 	 * current stride allows for in BAR 0/1, otherwise the remainder entries
157 	 * are inaccessible. MQES should reflect this, and this is just a
158 	 * fail-safe.
159 	 */
160 	max_entries =
161 	    (rman_get_size(ctrlr->resource) - nvme_mmio_offsetof(doorbell[0])) /
162 	    (1 << (ctrlr->dstrd + 1));
163 	num_entries = NVME_IO_ENTRIES;
164 	TUNABLE_INT_FETCH("hw.nvme.io_entries", &num_entries);
165 	cap_lo = nvme_mmio_read_4(ctrlr, cap_lo);
166 	mqes = NVME_CAP_LO_MQES(cap_lo);
167 	num_entries = min(num_entries, mqes + 1);
168 	num_entries = min(num_entries, max_entries);
169 
170 	num_trackers = NVME_IO_TRACKERS;
171 	TUNABLE_INT_FETCH("hw.nvme.io_trackers", &num_trackers);
172 
173 	num_trackers = max(num_trackers, NVME_MIN_IO_TRACKERS);
174 	num_trackers = min(num_trackers, NVME_MAX_IO_TRACKERS);
175 	/*
176 	 * No need to have more trackers than entries in the submit queue.  Note
177 	 * also that for a queue size of N, we can only have (N-1) commands
178 	 * outstanding, hence the "-1" here.
179 	 */
180 	num_trackers = min(num_trackers, (num_entries-1));
181 
182 	/*
183 	 * Our best estimate for the maximum number of I/Os that we should
184 	 * normally have in flight at one time. This should be viewed as a hint,
185 	 * not a hard limit and will need to be revisited when the upper layers
186 	 * of the storage system grows multi-queue support.
187 	 */
188 	ctrlr->max_hw_pend_io = num_trackers * ctrlr->num_io_queues * 3 / 4;
189 
190 	ctrlr->ioq = malloc(ctrlr->num_io_queues * sizeof(struct nvme_qpair),
191 	    M_NVME, M_ZERO | M_WAITOK);
192 
193 	for (i = c = n = 0; i < ctrlr->num_io_queues; i++, c += n) {
194 		qpair = &ctrlr->ioq[i];
195 
196 		/*
197 		 * Admin queue has ID=0. IO queues start at ID=1 -
198 		 *  hence the 'i+1' here.
199 		 */
200 		qpair->id = i + 1;
201 		if (ctrlr->num_io_queues > 1) {
202 			/* Find number of CPUs served by this queue. */
203 			for (n = 1; QP(ctrlr, c + n) == i; n++)
204 				;
205 			/* Shuffle multiple NVMe devices between CPUs. */
206 			qpair->cpu = c + (device_get_unit(ctrlr->dev)+n/2) % n;
207 			qpair->domain = pcpu_find(qpair->cpu)->pc_domain;
208 		} else {
209 			qpair->cpu = CPU_FFS(&cpuset_domain[ctrlr->domain]) - 1;
210 			qpair->domain = ctrlr->domain;
211 		}
212 
213 		/*
214 		 * For I/O queues, use the controller-wide max_xfer_size
215 		 *  calculated in nvme_attach().
216 		 */
217 		error = nvme_qpair_construct(qpair, num_entries, num_trackers,
218 		    ctrlr);
219 		if (error)
220 			return (error);
221 
222 		/*
223 		 * Do not bother binding interrupts if we only have one I/O
224 		 *  interrupt thread for this controller.
225 		 */
226 		if (ctrlr->num_io_queues > 1)
227 			bus_bind_intr(ctrlr->dev, qpair->res, qpair->cpu);
228 	}
229 
230 	return (0);
231 }
232 
233 static void
234 nvme_ctrlr_fail(struct nvme_controller *ctrlr)
235 {
236 	int i;
237 
238 	/*
239 	 * No need to disable queues before failing them. Failing is a superet
240 	 * of disabling (though pedantically we'd abort the AERs silently with
241 	 * a different error, though when we fail, that hardly matters).
242 	 */
243 	ctrlr->is_failed = true;
244 	nvme_qpair_fail(&ctrlr->adminq);
245 	if (ctrlr->ioq != NULL) {
246 		for (i = 0; i < ctrlr->num_io_queues; i++) {
247 			nvme_qpair_fail(&ctrlr->ioq[i]);
248 		}
249 	}
250 	nvme_notify_fail_consumers(ctrlr);
251 }
252 
253 /*
254  * Wait for RDY to change.
255  *
256  * Starts sleeping for 1us and geometrically increases it the longer we wait,
257  * capped at 1ms.
258  */
259 static int
260 nvme_ctrlr_wait_for_ready(struct nvme_controller *ctrlr, int desired_val)
261 {
262 	int timeout = ticks + MSEC_2_TICKS(ctrlr->ready_timeout_in_ms);
263 	sbintime_t delta_t = SBT_1US;
264 	uint32_t csts;
265 
266 	while (1) {
267 		csts = nvme_mmio_read_4(ctrlr, csts);
268 		if (csts == NVME_GONE)		/* Hot unplug. */
269 			return (ENXIO);
270 		if (NVMEV(NVME_CSTS_REG_RDY, csts) == desired_val)
271 			break;
272 		if (timeout - ticks < 0) {
273 			nvme_printf(ctrlr, "controller ready did not become %d "
274 			    "within %d ms\n", desired_val, ctrlr->ready_timeout_in_ms);
275 			return (ENXIO);
276 		}
277 
278 		pause_sbt("nvmerdy", delta_t, 0, C_PREL(1));
279 		delta_t = min(SBT_1MS, delta_t * 3 / 2);
280 	}
281 
282 	return (0);
283 }
284 
285 static int
286 nvme_ctrlr_disable(struct nvme_controller *ctrlr)
287 {
288 	uint32_t cc;
289 	uint32_t csts;
290 	uint8_t  en, rdy;
291 	int err;
292 
293 	cc = nvme_mmio_read_4(ctrlr, cc);
294 	csts = nvme_mmio_read_4(ctrlr, csts);
295 
296 	en = NVMEV(NVME_CC_REG_EN, cc);
297 	rdy = NVMEV(NVME_CSTS_REG_RDY, csts);
298 
299 	/*
300 	 * Per 3.1.5 in NVME 1.3 spec, transitioning CC.EN from 0 to 1
301 	 * when CSTS.RDY is 1 or transitioning CC.EN from 1 to 0 when
302 	 * CSTS.RDY is 0 "has undefined results" So make sure that CSTS.RDY
303 	 * isn't the desired value. Short circuit if we're already disabled.
304 	 */
305 	if (en == 0) {
306 		/* Wait for RDY == 0 or timeout & fail */
307 		if (rdy == 0)
308 			return (0);
309 		return (nvme_ctrlr_wait_for_ready(ctrlr, 0));
310 	}
311 	if (rdy == 0) {
312 		/* EN == 1, wait for  RDY == 1 or timeout & fail */
313 		err = nvme_ctrlr_wait_for_ready(ctrlr, 1);
314 		if (err != 0)
315 			return (err);
316 	}
317 
318 	cc &= ~NVMEM(NVME_CC_REG_EN);
319 	nvme_mmio_write_4(ctrlr, cc, cc);
320 
321 	/*
322 	 * A few drives have firmware bugs that freeze the drive if we access
323 	 * the mmio too soon after we disable.
324 	 */
325 	if (ctrlr->quirks & QUIRK_DELAY_B4_CHK_RDY)
326 		pause("nvmeR", MSEC_2_TICKS(B4_CHK_RDY_DELAY_MS));
327 	return (nvme_ctrlr_wait_for_ready(ctrlr, 0));
328 }
329 
330 static int
331 nvme_ctrlr_enable(struct nvme_controller *ctrlr)
332 {
333 	uint32_t	cc;
334 	uint32_t	csts;
335 	uint32_t	aqa;
336 	uint32_t	qsize;
337 	uint8_t		en, rdy;
338 	int		err;
339 
340 	cc = nvme_mmio_read_4(ctrlr, cc);
341 	csts = nvme_mmio_read_4(ctrlr, csts);
342 
343 	en = NVMEV(NVME_CC_REG_EN, cc);
344 	rdy = NVMEV(NVME_CSTS_REG_RDY, csts);
345 
346 	/*
347 	 * See note in nvme_ctrlr_disable. Short circuit if we're already enabled.
348 	 */
349 	if (en == 1) {
350 		if (rdy == 1)
351 			return (0);
352 		return (nvme_ctrlr_wait_for_ready(ctrlr, 1));
353 	}
354 
355 	/* EN == 0 already wait for RDY == 0 or timeout & fail */
356 	err = nvme_ctrlr_wait_for_ready(ctrlr, 0);
357 	if (err != 0)
358 		return (err);
359 
360 	nvme_mmio_write_8(ctrlr, asq, ctrlr->adminq.cmd_bus_addr);
361 	nvme_mmio_write_8(ctrlr, acq, ctrlr->adminq.cpl_bus_addr);
362 
363 	/* acqs and asqs are 0-based. */
364 	qsize = ctrlr->adminq.num_entries - 1;
365 
366 	aqa = 0;
367 	aqa |= NVMEF(NVME_AQA_REG_ACQS, qsize);
368 	aqa |= NVMEF(NVME_AQA_REG_ASQS, qsize);
369 	nvme_mmio_write_4(ctrlr, aqa, aqa);
370 
371 	/* Initialization values for CC */
372 	cc = 0;
373 	cc |= NVMEF(NVME_CC_REG_EN, 1);
374 	cc |= NVMEF(NVME_CC_REG_CSS, 0);
375 	cc |= NVMEF(NVME_CC_REG_AMS, 0);
376 	cc |= NVMEF(NVME_CC_REG_SHN, 0);
377 	cc |= NVMEF(NVME_CC_REG_IOSQES, 6); /* SQ entry size == 64 == 2^6 */
378 	cc |= NVMEF(NVME_CC_REG_IOCQES, 4); /* CQ entry size == 16 == 2^4 */
379 
380 	/*
381 	 * Use the Memory Page Size selected during device initialization.  Note
382 	 * that value stored in mps is suitable to use here without adjusting by
383 	 * NVME_MPS_SHIFT.
384 	 */
385 	cc |= NVMEF(NVME_CC_REG_MPS, ctrlr->mps);
386 
387 	nvme_ctrlr_barrier(ctrlr, BUS_SPACE_BARRIER_WRITE);
388 	nvme_mmio_write_4(ctrlr, cc, cc);
389 
390 	return (nvme_ctrlr_wait_for_ready(ctrlr, 1));
391 }
392 
393 static void
394 nvme_ctrlr_disable_qpairs(struct nvme_controller *ctrlr)
395 {
396 	int i;
397 
398 	nvme_admin_qpair_disable(&ctrlr->adminq);
399 	/*
400 	 * I/O queues are not allocated before the initial HW
401 	 *  reset, so do not try to disable them.  Use is_initialized
402 	 *  to determine if this is the initial HW reset.
403 	 */
404 	if (ctrlr->is_initialized) {
405 		for (i = 0; i < ctrlr->num_io_queues; i++)
406 			nvme_io_qpair_disable(&ctrlr->ioq[i]);
407 	}
408 }
409 
410 static int
411 nvme_ctrlr_hw_reset(struct nvme_controller *ctrlr)
412 {
413 	int err;
414 
415 	TSENTER();
416 
417 	nvme_ctrlr_disable_qpairs(ctrlr);
418 
419 	err = nvme_ctrlr_disable(ctrlr);
420 	if (err != 0)
421 		goto out;
422 
423 	err = nvme_ctrlr_enable(ctrlr);
424 out:
425 
426 	TSEXIT();
427 	return (err);
428 }
429 
430 void
431 nvme_ctrlr_reset(struct nvme_controller *ctrlr)
432 {
433 	int cmpset;
434 
435 	cmpset = atomic_cmpset_32(&ctrlr->is_resetting, 0, 1);
436 
437 	if (cmpset == 0 || ctrlr->is_failed)
438 		/*
439 		 * Controller is already resetting or has failed.  Return
440 		 *  immediately since there is no need to kick off another
441 		 *  reset in these cases.
442 		 */
443 		return;
444 
445 	if (!ctrlr->is_dying)
446 		taskqueue_enqueue(ctrlr->taskqueue, &ctrlr->reset_task);
447 }
448 
449 static int
450 nvme_ctrlr_identify(struct nvme_controller *ctrlr)
451 {
452 	struct nvme_completion_poll_status	status;
453 
454 	status.done = 0;
455 	nvme_ctrlr_cmd_identify_controller(ctrlr, &ctrlr->cdata,
456 	    nvme_completion_poll_cb, &status);
457 	nvme_completion_poll(&status);
458 	if (nvme_completion_is_error(&status.cpl)) {
459 		nvme_printf(ctrlr, "nvme_identify_controller failed!\n");
460 		return (ENXIO);
461 	}
462 
463 	/* Convert data to host endian */
464 	nvme_controller_data_swapbytes(&ctrlr->cdata);
465 
466 	/*
467 	 * Use MDTS to ensure our default max_xfer_size doesn't exceed what the
468 	 *  controller supports.
469 	 */
470 	if (ctrlr->cdata.mdts > 0)
471 		ctrlr->max_xfer_size = min(ctrlr->max_xfer_size,
472 		    1 << (ctrlr->cdata.mdts + NVME_MPS_SHIFT +
473 			NVME_CAP_HI_MPSMIN(ctrlr->cap_hi)));
474 
475 	return (0);
476 }
477 
478 static int
479 nvme_ctrlr_set_num_qpairs(struct nvme_controller *ctrlr)
480 {
481 	struct nvme_completion_poll_status	status;
482 	int					cq_allocated, sq_allocated;
483 
484 	status.done = 0;
485 	nvme_ctrlr_cmd_set_num_queues(ctrlr, ctrlr->num_io_queues,
486 	    nvme_completion_poll_cb, &status);
487 	nvme_completion_poll(&status);
488 	if (nvme_completion_is_error(&status.cpl)) {
489 		nvme_printf(ctrlr, "nvme_ctrlr_set_num_qpairs failed!\n");
490 		return (ENXIO);
491 	}
492 
493 	/*
494 	 * Data in cdw0 is 0-based.
495 	 * Lower 16-bits indicate number of submission queues allocated.
496 	 * Upper 16-bits indicate number of completion queues allocated.
497 	 */
498 	sq_allocated = (status.cpl.cdw0 & 0xFFFF) + 1;
499 	cq_allocated = (status.cpl.cdw0 >> 16) + 1;
500 
501 	/*
502 	 * Controller may allocate more queues than we requested,
503 	 *  so use the minimum of the number requested and what was
504 	 *  actually allocated.
505 	 */
506 	ctrlr->num_io_queues = min(ctrlr->num_io_queues, sq_allocated);
507 	ctrlr->num_io_queues = min(ctrlr->num_io_queues, cq_allocated);
508 	if (ctrlr->num_io_queues > vm_ndomains)
509 		ctrlr->num_io_queues -= ctrlr->num_io_queues % vm_ndomains;
510 
511 	return (0);
512 }
513 
514 static int
515 nvme_ctrlr_create_qpairs(struct nvme_controller *ctrlr)
516 {
517 	struct nvme_completion_poll_status	status;
518 	struct nvme_qpair			*qpair;
519 	int					i;
520 
521 	for (i = 0; i < ctrlr->num_io_queues; i++) {
522 		qpair = &ctrlr->ioq[i];
523 
524 		status.done = 0;
525 		nvme_ctrlr_cmd_create_io_cq(ctrlr, qpair,
526 		    nvme_completion_poll_cb, &status);
527 		nvme_completion_poll(&status);
528 		if (nvme_completion_is_error(&status.cpl)) {
529 			nvme_printf(ctrlr, "nvme_create_io_cq failed!\n");
530 			return (ENXIO);
531 		}
532 
533 		status.done = 0;
534 		nvme_ctrlr_cmd_create_io_sq(ctrlr, qpair,
535 		    nvme_completion_poll_cb, &status);
536 		nvme_completion_poll(&status);
537 		if (nvme_completion_is_error(&status.cpl)) {
538 			nvme_printf(ctrlr, "nvme_create_io_sq failed!\n");
539 			return (ENXIO);
540 		}
541 	}
542 
543 	return (0);
544 }
545 
546 static int
547 nvme_ctrlr_delete_qpairs(struct nvme_controller *ctrlr)
548 {
549 	struct nvme_completion_poll_status	status;
550 	struct nvme_qpair			*qpair;
551 
552 	for (int i = 0; i < ctrlr->num_io_queues; i++) {
553 		qpair = &ctrlr->ioq[i];
554 
555 		status.done = 0;
556 		nvme_ctrlr_cmd_delete_io_sq(ctrlr, qpair,
557 		    nvme_completion_poll_cb, &status);
558 		nvme_completion_poll(&status);
559 		if (nvme_completion_is_error(&status.cpl)) {
560 			nvme_printf(ctrlr, "nvme_destroy_io_sq failed!\n");
561 			return (ENXIO);
562 		}
563 
564 		status.done = 0;
565 		nvme_ctrlr_cmd_delete_io_cq(ctrlr, qpair,
566 		    nvme_completion_poll_cb, &status);
567 		nvme_completion_poll(&status);
568 		if (nvme_completion_is_error(&status.cpl)) {
569 			nvme_printf(ctrlr, "nvme_destroy_io_cq failed!\n");
570 			return (ENXIO);
571 		}
572 	}
573 
574 	return (0);
575 }
576 
577 static int
578 nvme_ctrlr_construct_namespaces(struct nvme_controller *ctrlr)
579 {
580 	struct nvme_namespace	*ns;
581 	uint32_t 		i;
582 
583 	for (i = 0; i < min(ctrlr->cdata.nn, NVME_MAX_NAMESPACES); i++) {
584 		ns = &ctrlr->ns[i];
585 		nvme_ns_construct(ns, i+1, ctrlr);
586 	}
587 
588 	return (0);
589 }
590 
591 static bool
592 is_log_page_id_valid(uint8_t page_id)
593 {
594 
595 	switch (page_id) {
596 	case NVME_LOG_ERROR:
597 	case NVME_LOG_HEALTH_INFORMATION:
598 	case NVME_LOG_FIRMWARE_SLOT:
599 	case NVME_LOG_CHANGED_NAMESPACE:
600 	case NVME_LOG_COMMAND_EFFECT:
601 	case NVME_LOG_RES_NOTIFICATION:
602 	case NVME_LOG_SANITIZE_STATUS:
603 		return (true);
604 	}
605 
606 	return (false);
607 }
608 
609 static uint32_t
610 nvme_ctrlr_get_log_page_size(struct nvme_controller *ctrlr, uint8_t page_id)
611 {
612 	uint32_t	log_page_size;
613 
614 	switch (page_id) {
615 	case NVME_LOG_ERROR:
616 		log_page_size = min(
617 		    sizeof(struct nvme_error_information_entry) *
618 		    (ctrlr->cdata.elpe + 1), NVME_MAX_AER_LOG_SIZE);
619 		break;
620 	case NVME_LOG_HEALTH_INFORMATION:
621 		log_page_size = sizeof(struct nvme_health_information_page);
622 		break;
623 	case NVME_LOG_FIRMWARE_SLOT:
624 		log_page_size = sizeof(struct nvme_firmware_page);
625 		break;
626 	case NVME_LOG_CHANGED_NAMESPACE:
627 		log_page_size = sizeof(struct nvme_ns_list);
628 		break;
629 	case NVME_LOG_COMMAND_EFFECT:
630 		log_page_size = sizeof(struct nvme_command_effects_page);
631 		break;
632 	case NVME_LOG_RES_NOTIFICATION:
633 		log_page_size = sizeof(struct nvme_res_notification_page);
634 		break;
635 	case NVME_LOG_SANITIZE_STATUS:
636 		log_page_size = sizeof(struct nvme_sanitize_status_page);
637 		break;
638 	default:
639 		log_page_size = 0;
640 		break;
641 	}
642 
643 	return (log_page_size);
644 }
645 
646 static void
647 nvme_ctrlr_log_critical_warnings(struct nvme_controller *ctrlr,
648     uint8_t state)
649 {
650 
651 	if (state & NVME_CRIT_WARN_ST_AVAILABLE_SPARE)
652 		nvme_printf(ctrlr, "SMART WARNING: available spare space below threshold\n");
653 
654 	if (state & NVME_CRIT_WARN_ST_TEMPERATURE)
655 		nvme_printf(ctrlr, "SMART WARNING: temperature above threshold\n");
656 
657 	if (state & NVME_CRIT_WARN_ST_DEVICE_RELIABILITY)
658 		nvme_printf(ctrlr, "SMART WARNING: device reliability degraded\n");
659 
660 	if (state & NVME_CRIT_WARN_ST_READ_ONLY)
661 		nvme_printf(ctrlr, "SMART WARNING: media placed in read only mode\n");
662 
663 	if (state & NVME_CRIT_WARN_ST_VOLATILE_MEMORY_BACKUP)
664 		nvme_printf(ctrlr, "SMART WARNING: volatile memory backup device failed\n");
665 
666 	if (state & NVME_CRIT_WARN_ST_PERSISTENT_MEMORY_REGION)
667 		nvme_printf(ctrlr, "SMART WARNING: persistent memory read only or unreliable\n");
668 
669 	if (state & NVME_CRIT_WARN_ST_RESERVED_MASK)
670 		nvme_printf(ctrlr, "SMART WARNING: unknown critical warning(s): state = 0x%02x\n",
671 		    state & NVME_CRIT_WARN_ST_RESERVED_MASK);
672 
673 	nvme_ctrlr_devctl(ctrlr, "critical", "SMART_ERROR", "state=0x%02x", state);
674 }
675 
676 static void
677 nvme_ctrlr_async_event_log_page_cb(void *arg, const struct nvme_completion *cpl)
678 {
679 	struct nvme_async_event_request		*aer = arg;
680 	struct nvme_health_information_page	*health_info;
681 	struct nvme_ns_list			*nsl;
682 	struct nvme_error_information_entry	*err;
683 	int i;
684 
685 	/*
686 	 * If the log page fetch for some reason completed with an error,
687 	 *  don't pass log page data to the consumers.  In practice, this case
688 	 *  should never happen.
689 	 */
690 	if (nvme_completion_is_error(cpl))
691 		nvme_notify_async_consumers(aer->ctrlr, &aer->cpl,
692 		    aer->log_page_id, NULL, 0);
693 	else {
694 		/* Convert data to host endian */
695 		switch (aer->log_page_id) {
696 		case NVME_LOG_ERROR:
697 			err = (struct nvme_error_information_entry *)aer->log_page_buffer;
698 			for (i = 0; i < (aer->ctrlr->cdata.elpe + 1); i++)
699 				nvme_error_information_entry_swapbytes(err++);
700 			break;
701 		case NVME_LOG_HEALTH_INFORMATION:
702 			nvme_health_information_page_swapbytes(
703 			    (struct nvme_health_information_page *)aer->log_page_buffer);
704 			break;
705 		case NVME_LOG_CHANGED_NAMESPACE:
706 			nvme_ns_list_swapbytes(
707 			    (struct nvme_ns_list *)aer->log_page_buffer);
708 			break;
709 		case NVME_LOG_COMMAND_EFFECT:
710 			nvme_command_effects_page_swapbytes(
711 			    (struct nvme_command_effects_page *)aer->log_page_buffer);
712 			break;
713 		case NVME_LOG_RES_NOTIFICATION:
714 			nvme_res_notification_page_swapbytes(
715 			    (struct nvme_res_notification_page *)aer->log_page_buffer);
716 			break;
717 		case NVME_LOG_SANITIZE_STATUS:
718 			nvme_sanitize_status_page_swapbytes(
719 			    (struct nvme_sanitize_status_page *)aer->log_page_buffer);
720 			break;
721 		default:
722 			break;
723 		}
724 
725 		if (aer->log_page_id == NVME_LOG_HEALTH_INFORMATION) {
726 			health_info = (struct nvme_health_information_page *)
727 			    aer->log_page_buffer;
728 			nvme_ctrlr_log_critical_warnings(aer->ctrlr,
729 			    health_info->critical_warning);
730 			/*
731 			 * Critical warnings reported through the
732 			 *  SMART/health log page are persistent, so
733 			 *  clear the associated bits in the async event
734 			 *  config so that we do not receive repeated
735 			 *  notifications for the same event.
736 			 */
737 			aer->ctrlr->async_event_config &=
738 			    ~health_info->critical_warning;
739 			nvme_ctrlr_cmd_set_async_event_config(aer->ctrlr,
740 			    aer->ctrlr->async_event_config, NULL, NULL);
741 		} else if (aer->log_page_id == NVME_LOG_CHANGED_NAMESPACE &&
742 		    !nvme_use_nvd) {
743 			nsl = (struct nvme_ns_list *)aer->log_page_buffer;
744 			for (i = 0; i < nitems(nsl->ns) && nsl->ns[i] != 0; i++) {
745 				if (nsl->ns[i] > NVME_MAX_NAMESPACES)
746 					break;
747 				nvme_notify_ns(aer->ctrlr, nsl->ns[i]);
748 			}
749 		}
750 
751 		/*
752 		 * Pass the cpl data from the original async event completion,
753 		 *  not the log page fetch.
754 		 */
755 		nvme_notify_async_consumers(aer->ctrlr, &aer->cpl,
756 		    aer->log_page_id, aer->log_page_buffer, aer->log_page_size);
757 	}
758 
759 	/*
760 	 * Repost another asynchronous event request to replace the one
761 	 *  that just completed.
762 	 */
763 	nvme_ctrlr_construct_and_submit_aer(aer->ctrlr, aer);
764 }
765 
766 static void
767 nvme_ctrlr_async_event_cb(void *arg, const struct nvme_completion *cpl)
768 {
769 	struct nvme_async_event_request	*aer = arg;
770 
771 	if (nvme_completion_is_error(cpl)) {
772 		/*
773 		 *  Do not retry failed async event requests.  This avoids
774 		 *  infinite loops where a new async event request is submitted
775 		 *  to replace the one just failed, only to fail again and
776 		 *  perpetuate the loop.
777 		 */
778 		return;
779 	}
780 
781 	/* Associated log page is in bits 23:16 of completion entry dw0. */
782 	aer->log_page_id = NVMEV(NVME_ASYNC_EVENT_LOG_PAGE_ID, cpl->cdw0);
783 
784 	nvme_printf(aer->ctrlr, "async event occurred (type 0x%x, info 0x%02x,"
785 	    " page 0x%02x)\n", NVMEV(NVME_ASYNC_EVENT_TYPE, cpl->cdw0),
786 	    NVMEV(NVME_ASYNC_EVENT_INFO, cpl->cdw0),
787 	    aer->log_page_id);
788 
789 	if (is_log_page_id_valid(aer->log_page_id)) {
790 		aer->log_page_size = nvme_ctrlr_get_log_page_size(aer->ctrlr,
791 		    aer->log_page_id);
792 		memcpy(&aer->cpl, cpl, sizeof(*cpl));
793 		nvme_ctrlr_cmd_get_log_page(aer->ctrlr, aer->log_page_id,
794 		    NVME_GLOBAL_NAMESPACE_TAG, aer->log_page_buffer,
795 		    aer->log_page_size, nvme_ctrlr_async_event_log_page_cb,
796 		    aer);
797 		/* Wait to notify consumers until after log page is fetched. */
798 	} else {
799 		nvme_notify_async_consumers(aer->ctrlr, cpl, aer->log_page_id,
800 		    NULL, 0);
801 
802 		/*
803 		 * Repost another asynchronous event request to replace the one
804 		 *  that just completed.
805 		 */
806 		nvme_ctrlr_construct_and_submit_aer(aer->ctrlr, aer);
807 	}
808 }
809 
810 static void
811 nvme_ctrlr_construct_and_submit_aer(struct nvme_controller *ctrlr,
812     struct nvme_async_event_request *aer)
813 {
814 	struct nvme_request *req;
815 
816 	aer->ctrlr = ctrlr;
817 	req = nvme_allocate_request_null(nvme_ctrlr_async_event_cb, aer);
818 	aer->req = req;
819 
820 	/*
821 	 * Disable timeout here, since asynchronous event requests should by
822 	 *  nature never be timed out.
823 	 */
824 	req->timeout = false;
825 	req->cmd.opc = NVME_OPC_ASYNC_EVENT_REQUEST;
826 	nvme_ctrlr_submit_admin_request(ctrlr, req);
827 }
828 
829 static void
830 nvme_ctrlr_configure_aer(struct nvme_controller *ctrlr)
831 {
832 	struct nvme_completion_poll_status	status;
833 	struct nvme_async_event_request		*aer;
834 	uint32_t				i;
835 
836 	ctrlr->async_event_config = NVME_CRIT_WARN_ST_AVAILABLE_SPARE |
837 	    NVME_CRIT_WARN_ST_DEVICE_RELIABILITY |
838 	    NVME_CRIT_WARN_ST_READ_ONLY |
839 	    NVME_CRIT_WARN_ST_VOLATILE_MEMORY_BACKUP;
840 	if (ctrlr->cdata.ver >= NVME_REV(1, 2))
841 		ctrlr->async_event_config |=
842 		    ctrlr->cdata.oaes & (NVME_ASYNC_EVENT_NS_ATTRIBUTE |
843 			NVME_ASYNC_EVENT_FW_ACTIVATE);
844 
845 	status.done = 0;
846 	nvme_ctrlr_cmd_get_feature(ctrlr, NVME_FEAT_TEMPERATURE_THRESHOLD,
847 	    0, NULL, 0, nvme_completion_poll_cb, &status);
848 	nvme_completion_poll(&status);
849 	if (nvme_completion_is_error(&status.cpl) ||
850 	    (status.cpl.cdw0 & 0xFFFF) == 0xFFFF ||
851 	    (status.cpl.cdw0 & 0xFFFF) == 0x0000) {
852 		nvme_printf(ctrlr, "temperature threshold not supported\n");
853 	} else
854 		ctrlr->async_event_config |= NVME_CRIT_WARN_ST_TEMPERATURE;
855 
856 	nvme_ctrlr_cmd_set_async_event_config(ctrlr,
857 	    ctrlr->async_event_config, NULL, NULL);
858 
859 	/* aerl is a zero-based value, so we need to add 1 here. */
860 	ctrlr->num_aers = min(NVME_MAX_ASYNC_EVENTS, (ctrlr->cdata.aerl+1));
861 
862 	for (i = 0; i < ctrlr->num_aers; i++) {
863 		aer = &ctrlr->aer[i];
864 		nvme_ctrlr_construct_and_submit_aer(ctrlr, aer);
865 	}
866 }
867 
868 static void
869 nvme_ctrlr_configure_int_coalescing(struct nvme_controller *ctrlr)
870 {
871 
872 	ctrlr->int_coal_time = 0;
873 	TUNABLE_INT_FETCH("hw.nvme.int_coal_time",
874 	    &ctrlr->int_coal_time);
875 
876 	ctrlr->int_coal_threshold = 0;
877 	TUNABLE_INT_FETCH("hw.nvme.int_coal_threshold",
878 	    &ctrlr->int_coal_threshold);
879 
880 	nvme_ctrlr_cmd_set_interrupt_coalescing(ctrlr, ctrlr->int_coal_time,
881 	    ctrlr->int_coal_threshold, NULL, NULL);
882 }
883 
884 static void
885 nvme_ctrlr_hmb_free(struct nvme_controller *ctrlr)
886 {
887 	struct nvme_hmb_chunk *hmbc;
888 	int i;
889 
890 	if (ctrlr->hmb_desc_paddr) {
891 		bus_dmamap_unload(ctrlr->hmb_desc_tag, ctrlr->hmb_desc_map);
892 		bus_dmamem_free(ctrlr->hmb_desc_tag, ctrlr->hmb_desc_vaddr,
893 		    ctrlr->hmb_desc_map);
894 		ctrlr->hmb_desc_paddr = 0;
895 	}
896 	if (ctrlr->hmb_desc_tag) {
897 		bus_dma_tag_destroy(ctrlr->hmb_desc_tag);
898 		ctrlr->hmb_desc_tag = NULL;
899 	}
900 	for (i = 0; i < ctrlr->hmb_nchunks; i++) {
901 		hmbc = &ctrlr->hmb_chunks[i];
902 		bus_dmamap_unload(ctrlr->hmb_tag, hmbc->hmbc_map);
903 		bus_dmamem_free(ctrlr->hmb_tag, hmbc->hmbc_vaddr,
904 		    hmbc->hmbc_map);
905 	}
906 	ctrlr->hmb_nchunks = 0;
907 	if (ctrlr->hmb_tag) {
908 		bus_dma_tag_destroy(ctrlr->hmb_tag);
909 		ctrlr->hmb_tag = NULL;
910 	}
911 	if (ctrlr->hmb_chunks) {
912 		free(ctrlr->hmb_chunks, M_NVME);
913 		ctrlr->hmb_chunks = NULL;
914 	}
915 }
916 
917 static void
918 nvme_ctrlr_hmb_alloc(struct nvme_controller *ctrlr)
919 {
920 	struct nvme_hmb_chunk *hmbc;
921 	size_t pref, min, minc, size;
922 	int err, i;
923 	uint64_t max;
924 
925 	/* Limit HMB to 5% of RAM size per device by default. */
926 	max = (uint64_t)physmem * PAGE_SIZE / 20;
927 	TUNABLE_UINT64_FETCH("hw.nvme.hmb_max", &max);
928 
929 	/*
930 	 * Units of Host Memory Buffer in the Identify info are always in terms
931 	 * of 4k units.
932 	 */
933 	min = (long long unsigned)ctrlr->cdata.hmmin * NVME_HMB_UNITS;
934 	if (max == 0 || max < min)
935 		return;
936 	pref = MIN((long long unsigned)ctrlr->cdata.hmpre * NVME_HMB_UNITS, max);
937 	minc = MAX(ctrlr->cdata.hmminds * NVME_HMB_UNITS, ctrlr->page_size);
938 	if (min > 0 && ctrlr->cdata.hmmaxd > 0)
939 		minc = MAX(minc, min / ctrlr->cdata.hmmaxd);
940 	ctrlr->hmb_chunk = pref;
941 
942 again:
943 	/*
944 	 * However, the chunk sizes, number of chunks, and alignment of chunks
945 	 * are all based on the current MPS (ctrlr->page_size).
946 	 */
947 	ctrlr->hmb_chunk = roundup2(ctrlr->hmb_chunk, ctrlr->page_size);
948 	ctrlr->hmb_nchunks = howmany(pref, ctrlr->hmb_chunk);
949 	if (ctrlr->cdata.hmmaxd > 0 && ctrlr->hmb_nchunks > ctrlr->cdata.hmmaxd)
950 		ctrlr->hmb_nchunks = ctrlr->cdata.hmmaxd;
951 	ctrlr->hmb_chunks = malloc(sizeof(struct nvme_hmb_chunk) *
952 	    ctrlr->hmb_nchunks, M_NVME, M_WAITOK);
953 	err = bus_dma_tag_create(bus_get_dma_tag(ctrlr->dev),
954 	    ctrlr->page_size, 0, BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
955 	    ctrlr->hmb_chunk, 1, ctrlr->hmb_chunk, 0, NULL, NULL, &ctrlr->hmb_tag);
956 	if (err != 0) {
957 		nvme_printf(ctrlr, "HMB tag create failed %d\n", err);
958 		nvme_ctrlr_hmb_free(ctrlr);
959 		return;
960 	}
961 
962 	for (i = 0; i < ctrlr->hmb_nchunks; i++) {
963 		hmbc = &ctrlr->hmb_chunks[i];
964 		if (bus_dmamem_alloc(ctrlr->hmb_tag,
965 		    (void **)&hmbc->hmbc_vaddr, BUS_DMA_NOWAIT,
966 		    &hmbc->hmbc_map)) {
967 			nvme_printf(ctrlr, "failed to alloc HMB\n");
968 			break;
969 		}
970 		if (bus_dmamap_load(ctrlr->hmb_tag, hmbc->hmbc_map,
971 		    hmbc->hmbc_vaddr, ctrlr->hmb_chunk, nvme_single_map,
972 		    &hmbc->hmbc_paddr, BUS_DMA_NOWAIT) != 0) {
973 			bus_dmamem_free(ctrlr->hmb_tag, hmbc->hmbc_vaddr,
974 			    hmbc->hmbc_map);
975 			nvme_printf(ctrlr, "failed to load HMB\n");
976 			break;
977 		}
978 		bus_dmamap_sync(ctrlr->hmb_tag, hmbc->hmbc_map,
979 		    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
980 	}
981 
982 	if (i < ctrlr->hmb_nchunks && i * ctrlr->hmb_chunk < min &&
983 	    ctrlr->hmb_chunk / 2 >= minc) {
984 		ctrlr->hmb_nchunks = i;
985 		nvme_ctrlr_hmb_free(ctrlr);
986 		ctrlr->hmb_chunk /= 2;
987 		goto again;
988 	}
989 	ctrlr->hmb_nchunks = i;
990 	if (ctrlr->hmb_nchunks * ctrlr->hmb_chunk < min) {
991 		nvme_ctrlr_hmb_free(ctrlr);
992 		return;
993 	}
994 
995 	size = sizeof(struct nvme_hmb_desc) * ctrlr->hmb_nchunks;
996 	err = bus_dma_tag_create(bus_get_dma_tag(ctrlr->dev),
997 	    16, 0, BUS_SPACE_MAXADDR, BUS_SPACE_MAXADDR, NULL, NULL,
998 	    size, 1, size, 0, NULL, NULL, &ctrlr->hmb_desc_tag);
999 	if (err != 0) {
1000 		nvme_printf(ctrlr, "HMB desc tag create failed %d\n", err);
1001 		nvme_ctrlr_hmb_free(ctrlr);
1002 		return;
1003 	}
1004 	if (bus_dmamem_alloc(ctrlr->hmb_desc_tag,
1005 	    (void **)&ctrlr->hmb_desc_vaddr, BUS_DMA_WAITOK,
1006 	    &ctrlr->hmb_desc_map)) {
1007 		nvme_printf(ctrlr, "failed to alloc HMB desc\n");
1008 		nvme_ctrlr_hmb_free(ctrlr);
1009 		return;
1010 	}
1011 	if (bus_dmamap_load(ctrlr->hmb_desc_tag, ctrlr->hmb_desc_map,
1012 	    ctrlr->hmb_desc_vaddr, size, nvme_single_map,
1013 	    &ctrlr->hmb_desc_paddr, BUS_DMA_NOWAIT) != 0) {
1014 		bus_dmamem_free(ctrlr->hmb_desc_tag, ctrlr->hmb_desc_vaddr,
1015 		    ctrlr->hmb_desc_map);
1016 		nvme_printf(ctrlr, "failed to load HMB desc\n");
1017 		nvme_ctrlr_hmb_free(ctrlr);
1018 		return;
1019 	}
1020 
1021 	for (i = 0; i < ctrlr->hmb_nchunks; i++) {
1022 		memset(&ctrlr->hmb_desc_vaddr[i], 0,
1023 		    sizeof(struct nvme_hmb_desc));
1024 		ctrlr->hmb_desc_vaddr[i].addr =
1025 		    htole64(ctrlr->hmb_chunks[i].hmbc_paddr);
1026 		ctrlr->hmb_desc_vaddr[i].size = htole32(ctrlr->hmb_chunk / ctrlr->page_size);
1027 	}
1028 	bus_dmamap_sync(ctrlr->hmb_desc_tag, ctrlr->hmb_desc_map,
1029 	    BUS_DMASYNC_PREWRITE);
1030 
1031 	nvme_printf(ctrlr, "Allocated %lluMB host memory buffer\n",
1032 	    (long long unsigned)ctrlr->hmb_nchunks * ctrlr->hmb_chunk
1033 	    / 1024 / 1024);
1034 }
1035 
1036 static void
1037 nvme_ctrlr_hmb_enable(struct nvme_controller *ctrlr, bool enable, bool memret)
1038 {
1039 	struct nvme_completion_poll_status	status;
1040 	uint32_t cdw11;
1041 
1042 	cdw11 = 0;
1043 	if (enable)
1044 		cdw11 |= 1;
1045 	if (memret)
1046 		cdw11 |= 2;
1047 	status.done = 0;
1048 	nvme_ctrlr_cmd_set_feature(ctrlr, NVME_FEAT_HOST_MEMORY_BUFFER, cdw11,
1049 	    ctrlr->hmb_nchunks * ctrlr->hmb_chunk / ctrlr->page_size,
1050 	    ctrlr->hmb_desc_paddr, ctrlr->hmb_desc_paddr >> 32,
1051 	    ctrlr->hmb_nchunks, NULL, 0,
1052 	    nvme_completion_poll_cb, &status);
1053 	nvme_completion_poll(&status);
1054 	if (nvme_completion_is_error(&status.cpl))
1055 		nvme_printf(ctrlr, "nvme_ctrlr_hmb_enable failed!\n");
1056 }
1057 
1058 static void
1059 nvme_ctrlr_start(void *ctrlr_arg, bool resetting)
1060 {
1061 	struct nvme_controller *ctrlr = ctrlr_arg;
1062 	uint32_t old_num_io_queues;
1063 	int i;
1064 
1065 	TSENTER();
1066 
1067 	/*
1068 	 * Only reset adminq here when we are restarting the
1069 	 *  controller after a reset.  During initialization,
1070 	 *  we have already submitted admin commands to get
1071 	 *  the number of I/O queues supported, so cannot reset
1072 	 *  the adminq again here.
1073 	 */
1074 	if (resetting) {
1075 		nvme_qpair_reset(&ctrlr->adminq);
1076 		nvme_admin_qpair_enable(&ctrlr->adminq);
1077 	}
1078 
1079 	if (ctrlr->ioq != NULL) {
1080 		for (i = 0; i < ctrlr->num_io_queues; i++)
1081 			nvme_qpair_reset(&ctrlr->ioq[i]);
1082 	}
1083 
1084 	/*
1085 	 * If it was a reset on initialization command timeout, just
1086 	 * return here, letting initialization code fail gracefully.
1087 	 */
1088 	if (resetting && !ctrlr->is_initialized)
1089 		return;
1090 
1091 	if (resetting && nvme_ctrlr_identify(ctrlr) != 0) {
1092 		nvme_ctrlr_fail(ctrlr);
1093 		return;
1094 	}
1095 
1096 	/*
1097 	 * The number of qpairs are determined during controller initialization,
1098 	 *  including using NVMe SET_FEATURES/NUMBER_OF_QUEUES to determine the
1099 	 *  HW limit.  We call SET_FEATURES again here so that it gets called
1100 	 *  after any reset for controllers that depend on the driver to
1101 	 *  explicit specify how many queues it will use.  This value should
1102 	 *  never change between resets, so panic if somehow that does happen.
1103 	 */
1104 	if (resetting) {
1105 		old_num_io_queues = ctrlr->num_io_queues;
1106 		if (nvme_ctrlr_set_num_qpairs(ctrlr) != 0) {
1107 			nvme_ctrlr_fail(ctrlr);
1108 			return;
1109 		}
1110 
1111 		if (old_num_io_queues != ctrlr->num_io_queues) {
1112 			panic("num_io_queues changed from %u to %u",
1113 			      old_num_io_queues, ctrlr->num_io_queues);
1114 		}
1115 	}
1116 
1117 	if (ctrlr->cdata.hmpre > 0 && ctrlr->hmb_nchunks == 0) {
1118 		nvme_ctrlr_hmb_alloc(ctrlr);
1119 		if (ctrlr->hmb_nchunks > 0)
1120 			nvme_ctrlr_hmb_enable(ctrlr, true, false);
1121 	} else if (ctrlr->hmb_nchunks > 0)
1122 		nvme_ctrlr_hmb_enable(ctrlr, true, true);
1123 
1124 	if (nvme_ctrlr_create_qpairs(ctrlr) != 0) {
1125 		nvme_ctrlr_fail(ctrlr);
1126 		return;
1127 	}
1128 
1129 	if (nvme_ctrlr_construct_namespaces(ctrlr) != 0) {
1130 		nvme_ctrlr_fail(ctrlr);
1131 		return;
1132 	}
1133 
1134 	nvme_ctrlr_configure_aer(ctrlr);
1135 	nvme_ctrlr_configure_int_coalescing(ctrlr);
1136 
1137 	for (i = 0; i < ctrlr->num_io_queues; i++)
1138 		nvme_io_qpair_enable(&ctrlr->ioq[i]);
1139 	TSEXIT();
1140 }
1141 
1142 void
1143 nvme_ctrlr_start_config_hook(void *arg)
1144 {
1145 	struct nvme_controller *ctrlr = arg;
1146 
1147 	TSENTER();
1148 
1149 	if (nvme_ctrlr_hw_reset(ctrlr) != 0) {
1150 fail:
1151 		nvme_ctrlr_fail(ctrlr);
1152 		config_intrhook_disestablish(&ctrlr->config_hook);
1153 		return;
1154 	}
1155 
1156 	nvme_qpair_reset(&ctrlr->adminq);
1157 	nvme_admin_qpair_enable(&ctrlr->adminq);
1158 
1159 	if (nvme_ctrlr_identify(ctrlr) == 0 &&
1160 	    nvme_ctrlr_set_num_qpairs(ctrlr) == 0 &&
1161 	    nvme_ctrlr_construct_io_qpairs(ctrlr) == 0)
1162 		nvme_ctrlr_start(ctrlr, false);
1163 	else
1164 		goto fail;
1165 
1166 	nvme_sysctl_initialize_ctrlr(ctrlr);
1167 	config_intrhook_disestablish(&ctrlr->config_hook);
1168 
1169 	ctrlr->is_initialized = 1;
1170 	nvme_notify_new_controller(ctrlr);
1171 	TSEXIT();
1172 }
1173 
1174 static void
1175 nvme_ctrlr_reset_task(void *arg, int pending)
1176 {
1177 	struct nvme_controller	*ctrlr = arg;
1178 	int			status;
1179 
1180 	nvme_ctrlr_devctl_log(ctrlr, "RESET", "event=\"start\"");
1181 	status = nvme_ctrlr_hw_reset(ctrlr);
1182 	if (status == 0) {
1183 		nvme_ctrlr_devctl_log(ctrlr, "RESET", "event=\"success\"");
1184 		nvme_ctrlr_start(ctrlr, true);
1185 	} else {
1186 		nvme_ctrlr_devctl_log(ctrlr, "RESET", "event=\"timed_out\"");
1187 		nvme_ctrlr_fail(ctrlr);
1188 	}
1189 
1190 	atomic_cmpset_32(&ctrlr->is_resetting, 1, 0);
1191 }
1192 
1193 /*
1194  * Poll all the queues enabled on the device for completion.
1195  */
1196 void
1197 nvme_ctrlr_poll(struct nvme_controller *ctrlr)
1198 {
1199 	int i;
1200 
1201 	nvme_qpair_process_completions(&ctrlr->adminq);
1202 
1203 	for (i = 0; i < ctrlr->num_io_queues; i++)
1204 		if (ctrlr->ioq && ctrlr->ioq[i].cpl)
1205 			nvme_qpair_process_completions(&ctrlr->ioq[i]);
1206 }
1207 
1208 /*
1209  * Poll the single-vector interrupt case: num_io_queues will be 1 and
1210  * there's only a single vector. While we're polling, we mask further
1211  * interrupts in the controller.
1212  */
1213 void
1214 nvme_ctrlr_shared_handler(void *arg)
1215 {
1216 	struct nvme_controller *ctrlr = arg;
1217 
1218 	nvme_mmio_write_4(ctrlr, intms, 1);
1219 	nvme_ctrlr_poll(ctrlr);
1220 	nvme_mmio_write_4(ctrlr, intmc, 1);
1221 }
1222 
1223 static void
1224 nvme_pt_done(void *arg, const struct nvme_completion *cpl)
1225 {
1226 	struct nvme_pt_command *pt = arg;
1227 	struct mtx *mtx = pt->driver_lock;
1228 	uint16_t status;
1229 
1230 	bzero(&pt->cpl, sizeof(pt->cpl));
1231 	pt->cpl.cdw0 = cpl->cdw0;
1232 
1233 	status = cpl->status;
1234 	status &= ~NVMEM(NVME_STATUS_P);
1235 	pt->cpl.status = status;
1236 
1237 	mtx_lock(mtx);
1238 	pt->driver_lock = NULL;
1239 	wakeup(pt);
1240 	mtx_unlock(mtx);
1241 }
1242 
1243 int
1244 nvme_ctrlr_passthrough_cmd(struct nvme_controller *ctrlr,
1245     struct nvme_pt_command *pt, uint32_t nsid, int is_user_buffer,
1246     int is_admin_cmd)
1247 {
1248 	struct nvme_request	*req;
1249 	struct mtx		*mtx;
1250 	struct buf		*buf = NULL;
1251 	int			ret = 0;
1252 
1253 	if (pt->len > 0) {
1254 		if (pt->len > ctrlr->max_xfer_size) {
1255 			nvme_printf(ctrlr, "pt->len (%d) "
1256 			    "exceeds max_xfer_size (%d)\n", pt->len,
1257 			    ctrlr->max_xfer_size);
1258 			return EIO;
1259 		}
1260 		if (is_user_buffer) {
1261 			/*
1262 			 * Ensure the user buffer is wired for the duration of
1263 			 *  this pass-through command.
1264 			 */
1265 			PHOLD(curproc);
1266 			buf = uma_zalloc(pbuf_zone, M_WAITOK);
1267 			buf->b_iocmd = pt->is_read ? BIO_READ : BIO_WRITE;
1268 			if (vmapbuf(buf, pt->buf, pt->len, 1) < 0) {
1269 				ret = EFAULT;
1270 				goto err;
1271 			}
1272 			req = nvme_allocate_request_vaddr(buf->b_data, pt->len,
1273 			    nvme_pt_done, pt);
1274 		} else
1275 			req = nvme_allocate_request_vaddr(pt->buf, pt->len,
1276 			    nvme_pt_done, pt);
1277 	} else
1278 		req = nvme_allocate_request_null(nvme_pt_done, pt);
1279 
1280 	/* Assume user space already converted to little-endian */
1281 	req->cmd.opc = pt->cmd.opc;
1282 	req->cmd.fuse = pt->cmd.fuse;
1283 	req->cmd.rsvd2 = pt->cmd.rsvd2;
1284 	req->cmd.rsvd3 = pt->cmd.rsvd3;
1285 	req->cmd.cdw10 = pt->cmd.cdw10;
1286 	req->cmd.cdw11 = pt->cmd.cdw11;
1287 	req->cmd.cdw12 = pt->cmd.cdw12;
1288 	req->cmd.cdw13 = pt->cmd.cdw13;
1289 	req->cmd.cdw14 = pt->cmd.cdw14;
1290 	req->cmd.cdw15 = pt->cmd.cdw15;
1291 
1292 	req->cmd.nsid = htole32(nsid);
1293 
1294 	mtx = mtx_pool_find(mtxpool_sleep, pt);
1295 	pt->driver_lock = mtx;
1296 
1297 	if (is_admin_cmd)
1298 		nvme_ctrlr_submit_admin_request(ctrlr, req);
1299 	else
1300 		nvme_ctrlr_submit_io_request(ctrlr, req);
1301 
1302 	mtx_lock(mtx);
1303 	while (pt->driver_lock != NULL)
1304 		mtx_sleep(pt, mtx, PRIBIO, "nvme_pt", 0);
1305 	mtx_unlock(mtx);
1306 
1307 	if (buf != NULL) {
1308 		vunmapbuf(buf);
1309 err:
1310 		uma_zfree(pbuf_zone, buf);
1311 		PRELE(curproc);
1312 	}
1313 
1314 	return (ret);
1315 }
1316 
1317 static int
1318 nvme_ctrlr_ioctl(struct cdev *cdev, u_long cmd, caddr_t arg, int flag,
1319     struct thread *td)
1320 {
1321 	struct nvme_controller			*ctrlr;
1322 	struct nvme_pt_command			*pt;
1323 
1324 	ctrlr = cdev->si_drv1;
1325 
1326 	switch (cmd) {
1327 	case NVME_RESET_CONTROLLER:
1328 		nvme_ctrlr_reset(ctrlr);
1329 		break;
1330 	case NVME_PASSTHROUGH_CMD:
1331 		pt = (struct nvme_pt_command *)arg;
1332 		return (nvme_ctrlr_passthrough_cmd(ctrlr, pt, le32toh(pt->cmd.nsid),
1333 		    1 /* is_user_buffer */, 1 /* is_admin_cmd */));
1334 	case NVME_GET_NSID:
1335 	{
1336 		struct nvme_get_nsid *gnsid = (struct nvme_get_nsid *)arg;
1337 		strncpy(gnsid->cdev, device_get_nameunit(ctrlr->dev),
1338 		    sizeof(gnsid->cdev));
1339 		gnsid->cdev[sizeof(gnsid->cdev) - 1] = '\0';
1340 		gnsid->nsid = 0;
1341 		break;
1342 	}
1343 	case NVME_GET_MAX_XFER_SIZE:
1344 		*(uint64_t *)arg = ctrlr->max_xfer_size;
1345 		break;
1346 	default:
1347 		return (ENOTTY);
1348 	}
1349 
1350 	return (0);
1351 }
1352 
1353 static struct cdevsw nvme_ctrlr_cdevsw = {
1354 	.d_version =	D_VERSION,
1355 	.d_flags =	0,
1356 	.d_ioctl =	nvme_ctrlr_ioctl
1357 };
1358 
1359 int
1360 nvme_ctrlr_construct(struct nvme_controller *ctrlr, device_t dev)
1361 {
1362 	struct make_dev_args	md_args;
1363 	uint32_t	cap_lo;
1364 	uint32_t	cap_hi;
1365 	uint32_t	to, vs, pmrcap;
1366 	int		status, timeout_period;
1367 
1368 	ctrlr->dev = dev;
1369 
1370 	mtx_init(&ctrlr->lock, "nvme ctrlr lock", NULL, MTX_DEF);
1371 	if (bus_get_domain(dev, &ctrlr->domain) != 0)
1372 		ctrlr->domain = 0;
1373 
1374 	ctrlr->cap_lo = cap_lo = nvme_mmio_read_4(ctrlr, cap_lo);
1375 	if (bootverbose) {
1376 		device_printf(dev, "CapLo: 0x%08x: MQES %u%s%s%s%s, TO %u\n",
1377 		    cap_lo, NVME_CAP_LO_MQES(cap_lo),
1378 		    NVME_CAP_LO_CQR(cap_lo) ? ", CQR" : "",
1379 		    NVME_CAP_LO_AMS(cap_lo) ? ", AMS" : "",
1380 		    (NVME_CAP_LO_AMS(cap_lo) & 0x1) ? " WRRwUPC" : "",
1381 		    (NVME_CAP_LO_AMS(cap_lo) & 0x2) ? " VS" : "",
1382 		    NVME_CAP_LO_TO(cap_lo));
1383 	}
1384 	ctrlr->cap_hi = cap_hi = nvme_mmio_read_4(ctrlr, cap_hi);
1385 	if (bootverbose) {
1386 		device_printf(dev, "CapHi: 0x%08x: DSTRD %u%s, CSS %x%s, "
1387 		    "CPS %x, MPSMIN %u, MPSMAX %u%s%s%s%s%s\n", cap_hi,
1388 		    NVME_CAP_HI_DSTRD(cap_hi),
1389 		    NVME_CAP_HI_NSSRS(cap_hi) ? ", NSSRS" : "",
1390 		    NVME_CAP_HI_CSS(cap_hi),
1391 		    NVME_CAP_HI_BPS(cap_hi) ? ", BPS" : "",
1392 		    NVME_CAP_HI_CPS(cap_hi),
1393 		    NVME_CAP_HI_MPSMIN(cap_hi),
1394 		    NVME_CAP_HI_MPSMAX(cap_hi),
1395 		    NVME_CAP_HI_PMRS(cap_hi) ? ", PMRS" : "",
1396 		    NVME_CAP_HI_CMBS(cap_hi) ? ", CMBS" : "",
1397 		    NVME_CAP_HI_NSSS(cap_hi) ? ", NSSS" : "",
1398 		    NVME_CAP_HI_CRWMS(cap_hi) ? ", CRWMS" : "",
1399 		    NVME_CAP_HI_CRIMS(cap_hi) ? ", CRIMS" : "");
1400 	}
1401 	if (bootverbose) {
1402 		vs = nvme_mmio_read_4(ctrlr, vs);
1403 		device_printf(dev, "Version: 0x%08x: %d.%d\n", vs,
1404 		    NVME_MAJOR(vs), NVME_MINOR(vs));
1405 	}
1406 	if (bootverbose && NVME_CAP_HI_PMRS(cap_hi)) {
1407 		pmrcap = nvme_mmio_read_4(ctrlr, pmrcap);
1408 		device_printf(dev, "PMRCap: 0x%08x: BIR %u%s%s, PMRTU %u, "
1409 		    "PMRWBM %x, PMRTO %u%s\n", pmrcap,
1410 		    NVME_PMRCAP_BIR(pmrcap),
1411 		    NVME_PMRCAP_RDS(pmrcap) ? ", RDS" : "",
1412 		    NVME_PMRCAP_WDS(pmrcap) ? ", WDS" : "",
1413 		    NVME_PMRCAP_PMRTU(pmrcap),
1414 		    NVME_PMRCAP_PMRWBM(pmrcap),
1415 		    NVME_PMRCAP_PMRTO(pmrcap),
1416 		    NVME_PMRCAP_CMSS(pmrcap) ? ", CMSS" : "");
1417 	}
1418 
1419 	ctrlr->dstrd = NVME_CAP_HI_DSTRD(cap_hi) + 2;
1420 
1421 	ctrlr->mps = NVME_CAP_HI_MPSMIN(cap_hi);
1422 	ctrlr->page_size = 1 << (NVME_MPS_SHIFT + ctrlr->mps);
1423 
1424 	/* Get ready timeout value from controller, in units of 500ms. */
1425 	to = NVME_CAP_LO_TO(cap_lo) + 1;
1426 	ctrlr->ready_timeout_in_ms = to * 500;
1427 
1428 	timeout_period = NVME_ADMIN_TIMEOUT_PERIOD;
1429 	TUNABLE_INT_FETCH("hw.nvme.admin_timeout_period", &timeout_period);
1430 	timeout_period = min(timeout_period, NVME_MAX_TIMEOUT_PERIOD);
1431 	timeout_period = max(timeout_period, NVME_MIN_TIMEOUT_PERIOD);
1432 	ctrlr->admin_timeout_period = timeout_period;
1433 
1434 	timeout_period = NVME_DEFAULT_TIMEOUT_PERIOD;
1435 	TUNABLE_INT_FETCH("hw.nvme.timeout_period", &timeout_period);
1436 	timeout_period = min(timeout_period, NVME_MAX_TIMEOUT_PERIOD);
1437 	timeout_period = max(timeout_period, NVME_MIN_TIMEOUT_PERIOD);
1438 	ctrlr->timeout_period = timeout_period;
1439 
1440 	nvme_retry_count = NVME_DEFAULT_RETRY_COUNT;
1441 	TUNABLE_INT_FETCH("hw.nvme.retry_count", &nvme_retry_count);
1442 
1443 	ctrlr->enable_aborts = 0;
1444 	TUNABLE_INT_FETCH("hw.nvme.enable_aborts", &ctrlr->enable_aborts);
1445 
1446 	/* Cap transfers by the maximum addressable by page-sized PRP (4KB pages -> 2MB). */
1447 	ctrlr->max_xfer_size = MIN(maxphys, (ctrlr->page_size / 8 * ctrlr->page_size));
1448 	if (nvme_ctrlr_construct_admin_qpair(ctrlr) != 0)
1449 		return (ENXIO);
1450 
1451 	/*
1452 	 * Create 2 threads for the taskqueue. The reset thread will block when
1453 	 * it detects that the controller has failed until all I/O has been
1454 	 * failed up the stack. The fail_req task needs to be able to run in
1455 	 * this case to finish the request failure for some cases.
1456 	 *
1457 	 * We could partially solve this race by draining the failed requeust
1458 	 * queue before proceding to free the sim, though nothing would stop
1459 	 * new I/O from coming in after we do that drain, but before we reach
1460 	 * cam_sim_free, so this big hammer is used instead.
1461 	 */
1462 	ctrlr->taskqueue = taskqueue_create("nvme_taskq", M_WAITOK,
1463 	    taskqueue_thread_enqueue, &ctrlr->taskqueue);
1464 	taskqueue_start_threads(&ctrlr->taskqueue, 2, PI_DISK, "nvme taskq");
1465 
1466 	ctrlr->is_resetting = 0;
1467 	ctrlr->is_initialized = 0;
1468 	ctrlr->notification_sent = 0;
1469 	TASK_INIT(&ctrlr->reset_task, 0, nvme_ctrlr_reset_task, ctrlr);
1470 	STAILQ_INIT(&ctrlr->fail_req);
1471 	ctrlr->is_failed = false;
1472 
1473 	make_dev_args_init(&md_args);
1474 	md_args.mda_devsw = &nvme_ctrlr_cdevsw;
1475 	md_args.mda_uid = UID_ROOT;
1476 	md_args.mda_gid = GID_WHEEL;
1477 	md_args.mda_mode = 0600;
1478 	md_args.mda_unit = device_get_unit(dev);
1479 	md_args.mda_si_drv1 = (void *)ctrlr;
1480 	status = make_dev_s(&md_args, &ctrlr->cdev, "nvme%d",
1481 	    device_get_unit(dev));
1482 	if (status != 0)
1483 		return (ENXIO);
1484 
1485 	return (0);
1486 }
1487 
1488 void
1489 nvme_ctrlr_destruct(struct nvme_controller *ctrlr, device_t dev)
1490 {
1491 	int	gone, i;
1492 
1493 	ctrlr->is_dying = true;
1494 
1495 	if (ctrlr->resource == NULL)
1496 		goto nores;
1497 	if (!mtx_initialized(&ctrlr->adminq.lock))
1498 		goto noadminq;
1499 
1500 	/*
1501 	 * Check whether it is a hot unplug or a clean driver detach.
1502 	 * If device is not there any more, skip any shutdown commands.
1503 	 */
1504 	gone = (nvme_mmio_read_4(ctrlr, csts) == NVME_GONE);
1505 	if (gone)
1506 		nvme_ctrlr_fail(ctrlr);
1507 	else
1508 		nvme_notify_fail_consumers(ctrlr);
1509 
1510 	for (i = 0; i < NVME_MAX_NAMESPACES; i++)
1511 		nvme_ns_destruct(&ctrlr->ns[i]);
1512 
1513 	if (ctrlr->cdev)
1514 		destroy_dev(ctrlr->cdev);
1515 
1516 	if (ctrlr->is_initialized) {
1517 		if (!gone) {
1518 			if (ctrlr->hmb_nchunks > 0)
1519 				nvme_ctrlr_hmb_enable(ctrlr, false, false);
1520 			nvme_ctrlr_delete_qpairs(ctrlr);
1521 		}
1522 		nvme_ctrlr_hmb_free(ctrlr);
1523 	}
1524 	if (ctrlr->ioq != NULL) {
1525 		for (i = 0; i < ctrlr->num_io_queues; i++)
1526 			nvme_io_qpair_destroy(&ctrlr->ioq[i]);
1527 		free(ctrlr->ioq, M_NVME);
1528 	}
1529 	nvme_admin_qpair_destroy(&ctrlr->adminq);
1530 
1531 	/*
1532 	 *  Notify the controller of a shutdown, even though this is due to
1533 	 *   a driver unload, not a system shutdown (this path is not invoked
1534 	 *   during shutdown).  This ensures the controller receives a
1535 	 *   shutdown notification in case the system is shutdown before
1536 	 *   reloading the driver.
1537 	 */
1538 	if (!gone)
1539 		nvme_ctrlr_shutdown(ctrlr);
1540 
1541 	if (!gone)
1542 		nvme_ctrlr_disable(ctrlr);
1543 
1544 noadminq:
1545 	if (ctrlr->taskqueue)
1546 		taskqueue_free(ctrlr->taskqueue);
1547 
1548 	if (ctrlr->tag)
1549 		bus_teardown_intr(ctrlr->dev, ctrlr->res, ctrlr->tag);
1550 
1551 	if (ctrlr->res)
1552 		bus_release_resource(ctrlr->dev, SYS_RES_IRQ,
1553 		    rman_get_rid(ctrlr->res), ctrlr->res);
1554 
1555 	if (ctrlr->bar4_resource != NULL) {
1556 		bus_release_resource(dev, SYS_RES_MEMORY,
1557 		    ctrlr->bar4_resource_id, ctrlr->bar4_resource);
1558 	}
1559 
1560 	bus_release_resource(dev, SYS_RES_MEMORY,
1561 	    ctrlr->resource_id, ctrlr->resource);
1562 
1563 nores:
1564 	mtx_destroy(&ctrlr->lock);
1565 }
1566 
1567 void
1568 nvme_ctrlr_shutdown(struct nvme_controller *ctrlr)
1569 {
1570 	uint32_t	cc;
1571 	uint32_t	csts;
1572 	int		timeout;
1573 
1574 	cc = nvme_mmio_read_4(ctrlr, cc);
1575 	cc &= ~NVMEM(NVME_CC_REG_SHN);
1576 	cc |= NVMEF(NVME_CC_REG_SHN, NVME_SHN_NORMAL);
1577 	nvme_mmio_write_4(ctrlr, cc, cc);
1578 
1579 	timeout = ticks + (ctrlr->cdata.rtd3e == 0 ? 5 * hz :
1580 	    ((uint64_t)ctrlr->cdata.rtd3e * hz + 999999) / 1000000);
1581 	while (1) {
1582 		csts = nvme_mmio_read_4(ctrlr, csts);
1583 		if (csts == NVME_GONE)		/* Hot unplug. */
1584 			break;
1585 		if (NVME_CSTS_GET_SHST(csts) == NVME_SHST_COMPLETE)
1586 			break;
1587 		if (timeout - ticks < 0) {
1588 			nvme_printf(ctrlr, "shutdown timeout\n");
1589 			break;
1590 		}
1591 		pause("nvmeshut", 1);
1592 	}
1593 }
1594 
1595 void
1596 nvme_ctrlr_submit_admin_request(struct nvme_controller *ctrlr,
1597     struct nvme_request *req)
1598 {
1599 
1600 	nvme_qpair_submit_request(&ctrlr->adminq, req);
1601 }
1602 
1603 void
1604 nvme_ctrlr_submit_io_request(struct nvme_controller *ctrlr,
1605     struct nvme_request *req)
1606 {
1607 	struct nvme_qpair       *qpair;
1608 
1609 	qpair = &ctrlr->ioq[QP(ctrlr, curcpu)];
1610 	nvme_qpair_submit_request(qpair, req);
1611 }
1612 
1613 device_t
1614 nvme_ctrlr_get_device(struct nvme_controller *ctrlr)
1615 {
1616 
1617 	return (ctrlr->dev);
1618 }
1619 
1620 const struct nvme_controller_data *
1621 nvme_ctrlr_get_data(struct nvme_controller *ctrlr)
1622 {
1623 
1624 	return (&ctrlr->cdata);
1625 }
1626 
1627 int
1628 nvme_ctrlr_suspend(struct nvme_controller *ctrlr)
1629 {
1630 	int to = hz;
1631 
1632 	/*
1633 	 * Can't touch failed controllers, so it's already suspended.
1634 	 */
1635 	if (ctrlr->is_failed)
1636 		return (0);
1637 
1638 	/*
1639 	 * We don't want the reset taskqueue running, since it does similar
1640 	 * things, so prevent it from running after we start. Wait for any reset
1641 	 * that may have been started to complete. The reset process we follow
1642 	 * will ensure that any new I/O will queue and be given to the hardware
1643 	 * after we resume (though there should be none).
1644 	 */
1645 	while (atomic_cmpset_32(&ctrlr->is_resetting, 0, 1) == 0 && to-- > 0)
1646 		pause("nvmesusp", 1);
1647 	if (to <= 0) {
1648 		nvme_printf(ctrlr,
1649 		    "Competing reset task didn't finish. Try again later.\n");
1650 		return (EWOULDBLOCK);
1651 	}
1652 
1653 	if (ctrlr->hmb_nchunks > 0)
1654 		nvme_ctrlr_hmb_enable(ctrlr, false, false);
1655 
1656 	/*
1657 	 * Per Section 7.6.2 of NVMe spec 1.4, to properly suspend, we need to
1658 	 * delete the hardware I/O queues, and then shutdown. This properly
1659 	 * flushes any metadata the drive may have stored so it can survive
1660 	 * having its power removed and prevents the unsafe shutdown count from
1661 	 * incriminating. Once we delete the qpairs, we have to disable them
1662 	 * before shutting down.
1663 	 */
1664 	nvme_ctrlr_delete_qpairs(ctrlr);
1665 	nvme_ctrlr_disable_qpairs(ctrlr);
1666 	nvme_ctrlr_shutdown(ctrlr);
1667 
1668 	return (0);
1669 }
1670 
1671 int
1672 nvme_ctrlr_resume(struct nvme_controller *ctrlr)
1673 {
1674 
1675 	/*
1676 	 * Can't touch failed controllers, so nothing to do to resume.
1677 	 */
1678 	if (ctrlr->is_failed)
1679 		return (0);
1680 
1681 	if (nvme_ctrlr_hw_reset(ctrlr) != 0)
1682 		goto fail;
1683 
1684 	/*
1685 	 * Now that we've reset the hardware, we can restart the controller. Any
1686 	 * I/O that was pending is requeued. Any admin commands are aborted with
1687 	 * an error. Once we've restarted, take the controller out of reset.
1688 	 */
1689 	nvme_ctrlr_start(ctrlr, true);
1690 	(void)atomic_cmpset_32(&ctrlr->is_resetting, 1, 0);
1691 
1692 	return (0);
1693 fail:
1694 	/*
1695 	 * Since we can't bring the controller out of reset, announce and fail
1696 	 * the controller. However, we have to return success for the resume
1697 	 * itself, due to questionable APIs.
1698 	 */
1699 	nvme_printf(ctrlr, "Failed to reset on resume, failing.\n");
1700 	nvme_ctrlr_fail(ctrlr);
1701 	(void)atomic_cmpset_32(&ctrlr->is_resetting, 1, 0);
1702 	return (0);
1703 }
1704