xref: /netbsd/sys/dev/ic/nvme.c (revision a3822310)
1 /*	$NetBSD: nvme.c,v 1.54 2020/12/27 16:52:01 jmcneill Exp $	*/
2 /*	$OpenBSD: nvme.c,v 1.49 2016/04/18 05:59:50 dlg Exp $ */
3 
4 /*
5  * Copyright (c) 2014 David Gwynne <dlg@openbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/cdefs.h>
21 __KERNEL_RCSID(0, "$NetBSD: nvme.c,v 1.54 2020/12/27 16:52:01 jmcneill Exp $");
22 
23 #include <sys/param.h>
24 #include <sys/systm.h>
25 #include <sys/kernel.h>
26 #include <sys/atomic.h>
27 #include <sys/bus.h>
28 #include <sys/buf.h>
29 #include <sys/conf.h>
30 #include <sys/device.h>
31 #include <sys/kmem.h>
32 #include <sys/once.h>
33 #include <sys/proc.h>
34 #include <sys/queue.h>
35 #include <sys/mutex.h>
36 
37 #include <uvm/uvm_extern.h>
38 
39 #include <dev/ic/nvmereg.h>
40 #include <dev/ic/nvmevar.h>
41 #include <dev/ic/nvmeio.h>
42 
43 #include "ioconf.h"
44 
45 #define	B4_CHK_RDY_DELAY_MS	2300	/* workaround controller bug */
46 
47 int nvme_adminq_size = 32;
48 int nvme_ioq_size = 1024;
49 
50 static int	nvme_print(void *, const char *);
51 
52 static int	nvme_ready(struct nvme_softc *, uint32_t);
53 static int	nvme_enable(struct nvme_softc *, u_int);
54 static int	nvme_disable(struct nvme_softc *);
55 static int	nvme_shutdown(struct nvme_softc *);
56 
57 #ifdef NVME_DEBUG
58 static void	nvme_dumpregs(struct nvme_softc *);
59 #endif
60 static int	nvme_identify(struct nvme_softc *, u_int);
61 static void	nvme_fill_identify(struct nvme_queue *, struct nvme_ccb *,
62 		    void *);
63 
64 static int	nvme_ccbs_alloc(struct nvme_queue *, uint16_t);
65 static void	nvme_ccbs_free(struct nvme_queue *);
66 
67 static struct nvme_ccb *
68 		nvme_ccb_get(struct nvme_queue *, bool);
69 static void	nvme_ccb_put(struct nvme_queue *, struct nvme_ccb *);
70 
71 static int	nvme_poll(struct nvme_softc *, struct nvme_queue *,
72 		    struct nvme_ccb *, void (*)(struct nvme_queue *,
73 		    struct nvme_ccb *, void *), int);
74 static void	nvme_poll_fill(struct nvme_queue *, struct nvme_ccb *, void *);
75 static void	nvme_poll_done(struct nvme_queue *, struct nvme_ccb *,
76 		    struct nvme_cqe *);
77 static void	nvme_sqe_fill(struct nvme_queue *, struct nvme_ccb *, void *);
78 static void	nvme_empty_done(struct nvme_queue *, struct nvme_ccb *,
79 		    struct nvme_cqe *);
80 
81 static struct nvme_queue *
82 		nvme_q_alloc(struct nvme_softc *, uint16_t, u_int, u_int);
83 static int	nvme_q_create(struct nvme_softc *, struct nvme_queue *);
84 static int	nvme_q_delete(struct nvme_softc *, struct nvme_queue *);
85 static void	nvme_q_submit(struct nvme_softc *, struct nvme_queue *,
86 		    struct nvme_ccb *, void (*)(struct nvme_queue *,
87 		    struct nvme_ccb *, void *));
88 static int	nvme_q_complete(struct nvme_softc *, struct nvme_queue *q);
89 static void	nvme_q_free(struct nvme_softc *, struct nvme_queue *);
90 static void	nvme_q_wait_complete(struct nvme_softc *, struct nvme_queue *,
91 		    bool (*)(void *), void *);
92 
93 static struct nvme_dmamem *
94 		nvme_dmamem_alloc(struct nvme_softc *, size_t);
95 static void	nvme_dmamem_free(struct nvme_softc *, struct nvme_dmamem *);
96 static void	nvme_dmamem_sync(struct nvme_softc *, struct nvme_dmamem *,
97 		    int);
98 
99 static void	nvme_ns_io_fill(struct nvme_queue *, struct nvme_ccb *,
100 		    void *);
101 static void	nvme_ns_io_done(struct nvme_queue *, struct nvme_ccb *,
102 		    struct nvme_cqe *);
103 static void	nvme_ns_sync_fill(struct nvme_queue *, struct nvme_ccb *,
104 		    void *);
105 static void	nvme_ns_sync_done(struct nvme_queue *, struct nvme_ccb *,
106 		    struct nvme_cqe *);
107 static void	nvme_getcache_fill(struct nvme_queue *, struct nvme_ccb *,
108 		    void *);
109 static void	nvme_getcache_done(struct nvme_queue *, struct nvme_ccb *,
110 		    struct nvme_cqe *);
111 
112 static void	nvme_pt_fill(struct nvme_queue *, struct nvme_ccb *,
113 		    void *);
114 static void	nvme_pt_done(struct nvme_queue *, struct nvme_ccb *,
115 		    struct nvme_cqe *);
116 static int	nvme_command_passthrough(struct nvme_softc *,
117 		    struct nvme_pt_command *, uint16_t, struct lwp *, bool);
118 
119 static int	nvme_set_number_of_queues(struct nvme_softc *, u_int, u_int *,
120 		    u_int *);
121 
122 #define NVME_TIMO_QOP		5	/* queue create and delete timeout */
123 #define NVME_TIMO_IDENT		10	/* probe identify timeout */
124 #define NVME_TIMO_PT		-1	/* passthrough cmd timeout */
125 #define NVME_TIMO_SY		60	/* sync cache timeout */
126 
127 #define nvme_read4(_s, _r) \
128 	bus_space_read_4((_s)->sc_iot, (_s)->sc_ioh, (_r))
129 #define nvme_write4(_s, _r, _v) \
130 	bus_space_write_4((_s)->sc_iot, (_s)->sc_ioh, (_r), (_v))
131 /*
132  * Some controllers, at least Apple NVMe, always require split
133  * transfers, so don't use bus_space_{read,write}_8() on LP64.
134  */
135 static inline uint64_t
136 nvme_read8(struct nvme_softc *sc, bus_size_t r)
137 {
138 	uint64_t v;
139 	uint32_t *a = (uint32_t *)&v;
140 
141 #if _BYTE_ORDER == _LITTLE_ENDIAN
142 	a[0] = nvme_read4(sc, r);
143 	a[1] = nvme_read4(sc, r + 4);
144 #else /* _BYTE_ORDER == _LITTLE_ENDIAN */
145 	a[1] = nvme_read4(sc, r);
146 	a[0] = nvme_read4(sc, r + 4);
147 #endif
148 
149 	return v;
150 }
151 
152 static inline void
153 nvme_write8(struct nvme_softc *sc, bus_size_t r, uint64_t v)
154 {
155 	uint32_t *a = (uint32_t *)&v;
156 
157 #if _BYTE_ORDER == _LITTLE_ENDIAN
158 	nvme_write4(sc, r, a[0]);
159 	nvme_write4(sc, r + 4, a[1]);
160 #else /* _BYTE_ORDER == _LITTLE_ENDIAN */
161 	nvme_write4(sc, r, a[1]);
162 	nvme_write4(sc, r + 4, a[0]);
163 #endif
164 }
165 #define nvme_barrier(_s, _r, _l, _f) \
166 	bus_space_barrier((_s)->sc_iot, (_s)->sc_ioh, (_r), (_l), (_f))
167 
168 #ifdef NVME_DEBUG
169 static __used void
170 nvme_dumpregs(struct nvme_softc *sc)
171 {
172 	uint64_t r8;
173 	uint32_t r4;
174 
175 #define	DEVNAME(_sc) device_xname((_sc)->sc_dev)
176 	r8 = nvme_read8(sc, NVME_CAP);
177 	printf("%s: cap  0x%016"PRIx64"\n", DEVNAME(sc), nvme_read8(sc, NVME_CAP));
178 	printf("%s:  mpsmax %u (%u)\n", DEVNAME(sc),
179 	    (u_int)NVME_CAP_MPSMAX(r8), (1 << NVME_CAP_MPSMAX(r8)));
180 	printf("%s:  mpsmin %u (%u)\n", DEVNAME(sc),
181 	    (u_int)NVME_CAP_MPSMIN(r8), (1 << NVME_CAP_MPSMIN(r8)));
182 	printf("%s:  css %"PRIu64"\n", DEVNAME(sc), NVME_CAP_CSS(r8));
183 	printf("%s:  nssrs %"PRIu64"\n", DEVNAME(sc), NVME_CAP_NSSRS(r8));
184 	printf("%s:  dstrd %"PRIu64"\n", DEVNAME(sc), NVME_CAP_DSTRD(r8));
185 	printf("%s:  to %"PRIu64" msec\n", DEVNAME(sc), NVME_CAP_TO(r8));
186 	printf("%s:  ams %"PRIu64"\n", DEVNAME(sc), NVME_CAP_AMS(r8));
187 	printf("%s:  cqr %"PRIu64"\n", DEVNAME(sc), NVME_CAP_CQR(r8));
188 	printf("%s:  mqes %"PRIu64"\n", DEVNAME(sc), NVME_CAP_MQES(r8));
189 
190 	printf("%s: vs   0x%04x\n", DEVNAME(sc), nvme_read4(sc, NVME_VS));
191 
192 	r4 = nvme_read4(sc, NVME_CC);
193 	printf("%s: cc   0x%04x\n", DEVNAME(sc), r4);
194 	printf("%s:  iocqes %u (%u)\n", DEVNAME(sc), NVME_CC_IOCQES_R(r4),
195 	    (1 << NVME_CC_IOCQES_R(r4)));
196 	printf("%s:  iosqes %u (%u)\n", DEVNAME(sc), NVME_CC_IOSQES_R(r4),
197 	    (1 << NVME_CC_IOSQES_R(r4)));
198 	printf("%s:  shn %u\n", DEVNAME(sc), NVME_CC_SHN_R(r4));
199 	printf("%s:  ams %u\n", DEVNAME(sc), NVME_CC_AMS_R(r4));
200 	printf("%s:  mps %u (%u)\n", DEVNAME(sc), NVME_CC_MPS_R(r4),
201 	    (1 << NVME_CC_MPS_R(r4)));
202 	printf("%s:  css %u\n", DEVNAME(sc), NVME_CC_CSS_R(r4));
203 	printf("%s:  en %u\n", DEVNAME(sc), ISSET(r4, NVME_CC_EN) ? 1 : 0);
204 
205 	r4 = nvme_read4(sc, NVME_CSTS);
206 	printf("%s: csts 0x%08x\n", DEVNAME(sc), r4);
207 	printf("%s:  rdy %u\n", DEVNAME(sc), r4 & NVME_CSTS_RDY);
208 	printf("%s:  cfs %u\n", DEVNAME(sc), r4 & NVME_CSTS_CFS);
209 	printf("%s:  shst %x\n", DEVNAME(sc), r4 & NVME_CSTS_SHST_MASK);
210 
211 	r4 = nvme_read4(sc, NVME_AQA);
212 	printf("%s: aqa  0x%08x\n", DEVNAME(sc), r4);
213 	printf("%s:  acqs %u\n", DEVNAME(sc), NVME_AQA_ACQS_R(r4));
214 	printf("%s:  asqs %u\n", DEVNAME(sc), NVME_AQA_ASQS_R(r4));
215 
216 	printf("%s: asq  0x%016"PRIx64"\n", DEVNAME(sc), nvme_read8(sc, NVME_ASQ));
217 	printf("%s: acq  0x%016"PRIx64"\n", DEVNAME(sc), nvme_read8(sc, NVME_ACQ));
218 #undef	DEVNAME
219 }
220 #endif	/* NVME_DEBUG */
221 
222 static int
223 nvme_ready(struct nvme_softc *sc, uint32_t rdy)
224 {
225 	u_int i = 0;
226 
227 	while ((nvme_read4(sc, NVME_CSTS) & NVME_CSTS_RDY) != rdy) {
228 		if (i++ > sc->sc_rdy_to)
229 			return ENXIO;
230 
231 		delay(1000);
232 		nvme_barrier(sc, NVME_CSTS, 4, BUS_SPACE_BARRIER_READ);
233 	}
234 
235 	return 0;
236 }
237 
238 static int
239 nvme_enable(struct nvme_softc *sc, u_int mps)
240 {
241 	uint32_t cc, csts;
242 	int error;
243 
244 	cc = nvme_read4(sc, NVME_CC);
245 	csts = nvme_read4(sc, NVME_CSTS);
246 
247 	/*
248 	 * See note in nvme_disable. Short circuit if we're already enabled.
249 	 */
250 	if (ISSET(cc, NVME_CC_EN)) {
251 		if (ISSET(csts, NVME_CSTS_RDY))
252 			return 0;
253 
254 		goto waitready;
255 	} else {
256 		/* EN == 0 already wait for RDY == 0 or fail */
257 		error = nvme_ready(sc, 0);
258 		if (error)
259 			return error;
260 	}
261 
262 	nvme_write8(sc, NVME_ASQ, NVME_DMA_DVA(sc->sc_admin_q->q_sq_dmamem));
263 	nvme_barrier(sc, 0, sc->sc_ios, BUS_SPACE_BARRIER_WRITE);
264 	delay(5000);
265 	nvme_write8(sc, NVME_ACQ, NVME_DMA_DVA(sc->sc_admin_q->q_cq_dmamem));
266 	nvme_barrier(sc, 0, sc->sc_ios, BUS_SPACE_BARRIER_WRITE);
267 	delay(5000);
268 
269 	nvme_write4(sc, NVME_AQA, NVME_AQA_ACQS(sc->sc_admin_q->q_entries) |
270 	    NVME_AQA_ASQS(sc->sc_admin_q->q_entries));
271 	nvme_barrier(sc, 0, sc->sc_ios, BUS_SPACE_BARRIER_WRITE);
272 	delay(5000);
273 
274 	CLR(cc, NVME_CC_IOCQES_MASK | NVME_CC_IOSQES_MASK | NVME_CC_SHN_MASK |
275 	    NVME_CC_AMS_MASK | NVME_CC_MPS_MASK | NVME_CC_CSS_MASK);
276 	SET(cc, NVME_CC_IOSQES(ffs(64) - 1) | NVME_CC_IOCQES(ffs(16) - 1));
277 	SET(cc, NVME_CC_SHN(NVME_CC_SHN_NONE));
278 	SET(cc, NVME_CC_CSS(NVME_CC_CSS_NVM));
279 	SET(cc, NVME_CC_AMS(NVME_CC_AMS_RR));
280 	SET(cc, NVME_CC_MPS(mps));
281 	SET(cc, NVME_CC_EN);
282 
283 	nvme_write4(sc, NVME_CC, cc);
284 	nvme_barrier(sc, 0, sc->sc_ios,
285 	    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
286 
287     waitready:
288 	return nvme_ready(sc, NVME_CSTS_RDY);
289 }
290 
291 static int
292 nvme_disable(struct nvme_softc *sc)
293 {
294 	uint32_t cc, csts;
295 	int error;
296 
297 	cc = nvme_read4(sc, NVME_CC);
298 	csts = nvme_read4(sc, NVME_CSTS);
299 
300 	/*
301 	 * Per 3.1.5 in NVME 1.3 spec, transitioning CC.EN from 0 to 1
302 	 * when CSTS.RDY is 1 or transitioning CC.EN from 1 to 0 when
303 	 * CSTS.RDY is 0 "has undefined results" So make sure that CSTS.RDY
304 	 * isn't the desired value. Short circuit if we're already disabled.
305 	 */
306 	if (ISSET(cc, NVME_CC_EN)) {
307 		if (!ISSET(csts, NVME_CSTS_RDY)) {
308 			/* EN == 1, wait for RDY == 1 or fail */
309 			error = nvme_ready(sc, NVME_CSTS_RDY);
310 			if (error)
311 				return error;
312 		}
313 	} else {
314 		/* EN == 0 already wait for RDY == 0 */
315 		if (!ISSET(csts, NVME_CSTS_RDY))
316 			return 0;
317 
318 		goto waitready;
319 	}
320 
321 	CLR(cc, NVME_CC_EN);
322 	nvme_write4(sc, NVME_CC, cc);
323 	nvme_barrier(sc, 0, sc->sc_ios, BUS_SPACE_BARRIER_READ);
324 
325 	/*
326 	 * Some drives have issues with accessing the mmio after we disable,
327 	 * so delay for a bit after we write the bit to cope with these issues.
328 	 */
329 	if (ISSET(sc->sc_quirks, NVME_QUIRK_DELAY_B4_CHK_RDY))
330 		delay(B4_CHK_RDY_DELAY_MS);
331 
332     waitready:
333 	return nvme_ready(sc, 0);
334 }
335 
336 int
337 nvme_attach(struct nvme_softc *sc)
338 {
339 	uint64_t cap;
340 	uint32_t reg;
341 	u_int dstrd;
342 	u_int mps = PAGE_SHIFT;
343 	u_int ncq, nsq;
344 	uint16_t adminq_entries = nvme_adminq_size;
345 	uint16_t ioq_entries = nvme_ioq_size;
346 	int i;
347 
348 	reg = nvme_read4(sc, NVME_VS);
349 	if (reg == 0xffffffff) {
350 		aprint_error_dev(sc->sc_dev, "invalid mapping\n");
351 		return 1;
352 	}
353 
354 	if (NVME_VS_TER(reg) == 0)
355 		aprint_normal_dev(sc->sc_dev, "NVMe %d.%d\n", NVME_VS_MJR(reg),
356 		    NVME_VS_MNR(reg));
357 	else
358 		aprint_normal_dev(sc->sc_dev, "NVMe %d.%d.%d\n", NVME_VS_MJR(reg),
359 		    NVME_VS_MNR(reg), NVME_VS_TER(reg));
360 
361 	cap = nvme_read8(sc, NVME_CAP);
362 	dstrd = NVME_CAP_DSTRD(cap);
363 	if (NVME_CAP_MPSMIN(cap) > PAGE_SHIFT) {
364 		aprint_error_dev(sc->sc_dev, "NVMe minimum page size %u "
365 		    "is greater than CPU page size %u\n",
366 		    1 << NVME_CAP_MPSMIN(cap), 1 << PAGE_SHIFT);
367 		return 1;
368 	}
369 	if (NVME_CAP_MPSMAX(cap) < mps)
370 		mps = NVME_CAP_MPSMAX(cap);
371 	if (ioq_entries > NVME_CAP_MQES(cap))
372 		ioq_entries = NVME_CAP_MQES(cap);
373 
374 	/* set initial values to be used for admin queue during probe */
375 	sc->sc_rdy_to = NVME_CAP_TO(cap);
376 	sc->sc_mps = 1 << mps;
377 	sc->sc_mdts = MAXPHYS;
378 	sc->sc_max_sgl = btoc(round_page(sc->sc_mdts));
379 
380 	if (nvme_disable(sc) != 0) {
381 		aprint_error_dev(sc->sc_dev, "unable to disable controller\n");
382 		return 1;
383 	}
384 
385 	sc->sc_admin_q = nvme_q_alloc(sc, NVME_ADMIN_Q, adminq_entries, dstrd);
386 	if (sc->sc_admin_q == NULL) {
387 		aprint_error_dev(sc->sc_dev,
388 		    "unable to allocate admin queue\n");
389 		return 1;
390 	}
391 	if (sc->sc_intr_establish(sc, NVME_ADMIN_Q, sc->sc_admin_q))
392 		goto free_admin_q;
393 
394 	if (nvme_enable(sc, mps) != 0) {
395 		aprint_error_dev(sc->sc_dev, "unable to enable controller\n");
396 		goto disestablish_admin_q;
397 	}
398 
399 	if (nvme_identify(sc, NVME_CAP_MPSMIN(cap)) != 0) {
400 		aprint_error_dev(sc->sc_dev, "unable to identify controller\n");
401 		goto disable;
402 	}
403 	if (sc->sc_nn == 0) {
404 		aprint_error_dev(sc->sc_dev, "namespace not found\n");
405 		goto disable;
406 	}
407 
408 	/* we know how big things are now */
409 	sc->sc_max_sgl = sc->sc_mdts / sc->sc_mps;
410 
411 	/* reallocate ccbs of admin queue with new max sgl. */
412 	nvme_ccbs_free(sc->sc_admin_q);
413 	nvme_ccbs_alloc(sc->sc_admin_q, sc->sc_admin_q->q_entries);
414 
415 	if (sc->sc_use_mq) {
416 		/* Limit the number of queues to the number allocated in HW */
417 		if (nvme_set_number_of_queues(sc, sc->sc_nq, &ncq, &nsq) != 0) {
418 			aprint_error_dev(sc->sc_dev,
419 			    "unable to get number of queues\n");
420 			goto disable;
421 		}
422 		if (sc->sc_nq > ncq)
423 			sc->sc_nq = ncq;
424 		if (sc->sc_nq > nsq)
425 			sc->sc_nq = nsq;
426 	}
427 
428 	sc->sc_q = kmem_zalloc(sizeof(*sc->sc_q) * sc->sc_nq, KM_SLEEP);
429 	for (i = 0; i < sc->sc_nq; i++) {
430 		sc->sc_q[i] = nvme_q_alloc(sc, i + 1, ioq_entries, dstrd);
431 		if (sc->sc_q[i] == NULL) {
432 			aprint_error_dev(sc->sc_dev,
433 			    "unable to allocate io queue\n");
434 			goto free_q;
435 		}
436 		if (nvme_q_create(sc, sc->sc_q[i]) != 0) {
437 			aprint_error_dev(sc->sc_dev,
438 			    "unable to create io queue\n");
439 			nvme_q_free(sc, sc->sc_q[i]);
440 			goto free_q;
441 		}
442 	}
443 
444 	if (!sc->sc_use_mq)
445 		nvme_write4(sc, NVME_INTMC, 1);
446 
447 	/* probe subdevices */
448 	sc->sc_namespaces = kmem_zalloc(sizeof(*sc->sc_namespaces) * sc->sc_nn,
449 	    KM_SLEEP);
450 	nvme_rescan(sc->sc_dev, "nvme", &i);
451 
452 	return 0;
453 
454 free_q:
455 	while (--i >= 0) {
456 		nvme_q_delete(sc, sc->sc_q[i]);
457 		nvme_q_free(sc, sc->sc_q[i]);
458 	}
459 disable:
460 	nvme_disable(sc);
461 disestablish_admin_q:
462 	sc->sc_intr_disestablish(sc, NVME_ADMIN_Q);
463 free_admin_q:
464 	nvme_q_free(sc, sc->sc_admin_q);
465 
466 	return 1;
467 }
468 
469 int
470 nvme_rescan(device_t self, const char *attr, const int *flags)
471 {
472 	struct nvme_softc *sc = device_private(self);
473 	struct nvme_attach_args naa;
474 	struct nvm_namespace_format *f;
475 	struct nvme_namespace *ns;
476 	uint64_t cap;
477 	int ioq_entries = nvme_ioq_size;
478 	int i;
479 	int error;
480 
481 	cap = nvme_read8(sc, NVME_CAP);
482 	if (ioq_entries > NVME_CAP_MQES(cap))
483 		ioq_entries = NVME_CAP_MQES(cap);
484 
485 	for (i = 1; i <= sc->sc_nn; i++) {
486 		if (sc->sc_namespaces[i - 1].dev)
487 			continue;
488 
489 		/* identify to check for availability */
490 		error = nvme_ns_identify(sc, i);
491 		if (error) {
492 			aprint_error_dev(self, "couldn't identify namespace #%d\n", i);
493 			continue;
494 		}
495 
496 		ns = nvme_ns_get(sc, i);
497 		KASSERT(ns);
498 
499 		f = &ns->ident->lbaf[NVME_ID_NS_FLBAS(ns->ident->flbas)];
500 
501 		/*
502 		 * NVME1.0e 6.11 Identify command
503 		 *
504 		 * LBADS values smaller than 9 are not supported, a value
505 		 * of zero means that the format is not used.
506 		 */
507 		if (f->lbads < 9) {
508 			if (f->lbads > 0)
509 				aprint_error_dev(self,
510 						 "unsupported logical data size %u\n", f->lbads);
511 			continue;
512 		}
513 
514 		memset(&naa, 0, sizeof(naa));
515 		naa.naa_nsid = i;
516 		naa.naa_qentries = (ioq_entries - 1) * sc->sc_nq;
517 		naa.naa_maxphys = sc->sc_mdts;
518 		naa.naa_typename = sc->sc_modelname;
519 		sc->sc_namespaces[i - 1].dev = config_found(sc->sc_dev, &naa,
520 		    nvme_print);
521 	}
522 	return 0;
523 }
524 
525 static int
526 nvme_print(void *aux, const char *pnp)
527 {
528 	struct nvme_attach_args *naa = aux;
529 
530 	if (pnp)
531 		aprint_normal("ld at %s", pnp);
532 
533 	if (naa->naa_nsid > 0)
534 		aprint_normal(" nsid %d", naa->naa_nsid);
535 
536 	return UNCONF;
537 }
538 
539 int
540 nvme_detach(struct nvme_softc *sc, int flags)
541 {
542 	int i, error;
543 
544 	error = config_detach_children(sc->sc_dev, flags);
545 	if (error)
546 		return error;
547 
548 	error = nvme_shutdown(sc);
549 	if (error)
550 		return error;
551 
552 	/* from now on we are committed to detach, following will never fail */
553 	for (i = 0; i < sc->sc_nq; i++)
554 		nvme_q_free(sc, sc->sc_q[i]);
555 	kmem_free(sc->sc_q, sizeof(*sc->sc_q) * sc->sc_nq);
556 	nvme_q_free(sc, sc->sc_admin_q);
557 
558 	return 0;
559 }
560 
561 static int
562 nvme_shutdown(struct nvme_softc *sc)
563 {
564 	uint32_t cc, csts;
565 	bool disabled = false;
566 	int i;
567 
568 	if (!sc->sc_use_mq)
569 		nvme_write4(sc, NVME_INTMS, 1);
570 
571 	for (i = 0; i < sc->sc_nq; i++) {
572 		if (nvme_q_delete(sc, sc->sc_q[i]) != 0) {
573 			aprint_error_dev(sc->sc_dev,
574 			    "unable to delete io queue %d, disabling\n", i + 1);
575 			disabled = true;
576 		}
577 	}
578 	sc->sc_intr_disestablish(sc, NVME_ADMIN_Q);
579 	if (disabled)
580 		goto disable;
581 
582 	cc = nvme_read4(sc, NVME_CC);
583 	CLR(cc, NVME_CC_SHN_MASK);
584 	SET(cc, NVME_CC_SHN(NVME_CC_SHN_NORMAL));
585 	nvme_write4(sc, NVME_CC, cc);
586 
587 	for (i = 0; i < 4000; i++) {
588 		nvme_barrier(sc, 0, sc->sc_ios,
589 		    BUS_SPACE_BARRIER_READ | BUS_SPACE_BARRIER_WRITE);
590 		csts = nvme_read4(sc, NVME_CSTS);
591 		if ((csts & NVME_CSTS_SHST_MASK) == NVME_CSTS_SHST_DONE)
592 			return 0;
593 
594 		delay(1000);
595 	}
596 
597 	aprint_error_dev(sc->sc_dev, "unable to shudown, disabling\n");
598 
599 disable:
600 	nvme_disable(sc);
601 	return 0;
602 }
603 
604 void
605 nvme_childdet(device_t self, device_t child)
606 {
607 	struct nvme_softc *sc = device_private(self);
608 	int i;
609 
610 	for (i = 0; i < sc->sc_nn; i++) {
611 		if (sc->sc_namespaces[i].dev == child) {
612 			/* Already freed ns->ident. */
613 			sc->sc_namespaces[i].dev = NULL;
614 			break;
615 		}
616 	}
617 }
618 
619 int
620 nvme_ns_identify(struct nvme_softc *sc, uint16_t nsid)
621 {
622 	struct nvme_sqe sqe;
623 	struct nvm_identify_namespace *identify;
624 	struct nvme_dmamem *mem;
625 	struct nvme_ccb *ccb;
626 	struct nvme_namespace *ns;
627 	int rv;
628 
629 	KASSERT(nsid > 0);
630 
631 	ns = nvme_ns_get(sc, nsid);
632 	KASSERT(ns);
633 
634 	if (ns->ident != NULL)
635 		return 0;
636 
637 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
638 	KASSERT(ccb != NULL); /* it's a bug if we don't have spare ccb here */
639 
640 	mem = nvme_dmamem_alloc(sc, sizeof(*identify));
641 	if (mem == NULL) {
642 		nvme_ccb_put(sc->sc_admin_q, ccb);
643 		return ENOMEM;
644 	}
645 
646 	memset(&sqe, 0, sizeof(sqe));
647 	sqe.opcode = NVM_ADMIN_IDENTIFY;
648 	htolem32(&sqe.nsid, nsid);
649 	htolem64(&sqe.entry.prp[0], NVME_DMA_DVA(mem));
650 	htolem32(&sqe.cdw10, 0);
651 
652 	ccb->ccb_done = nvme_empty_done;
653 	ccb->ccb_cookie = &sqe;
654 
655 	nvme_dmamem_sync(sc, mem, BUS_DMASYNC_PREREAD);
656 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_IDENT);
657 	nvme_dmamem_sync(sc, mem, BUS_DMASYNC_POSTREAD);
658 
659 	nvme_ccb_put(sc->sc_admin_q, ccb);
660 
661 	if (rv != 0) {
662 		rv = EIO;
663 		goto done;
664 	}
665 
666 	/* commit */
667 
668 	identify = kmem_zalloc(sizeof(*identify), KM_SLEEP);
669 	*identify = *((volatile struct nvm_identify_namespace *)NVME_DMA_KVA(mem));
670 
671 	/* Convert data to host endian */
672 	nvme_identify_namespace_swapbytes(identify);
673 
674 	ns->ident = identify;
675 
676 done:
677 	nvme_dmamem_free(sc, mem);
678 
679 	return rv;
680 }
681 
682 int
683 nvme_ns_dobio(struct nvme_softc *sc, uint16_t nsid, void *cookie,
684     struct buf *bp, void *data, size_t datasize,
685     int secsize, daddr_t blkno, int flags, nvme_nnc_done nnc_done)
686 {
687 	struct nvme_queue *q = nvme_get_q(sc, bp, false);
688 	struct nvme_ccb *ccb;
689 	bus_dmamap_t dmap;
690 	int i, error;
691 
692 	ccb = nvme_ccb_get(q, false);
693 	if (ccb == NULL)
694 		return EAGAIN;
695 
696 	ccb->ccb_done = nvme_ns_io_done;
697 	ccb->ccb_cookie = cookie;
698 
699 	/* namespace context */
700 	ccb->nnc_nsid = nsid;
701 	ccb->nnc_flags = flags;
702 	ccb->nnc_buf = bp;
703 	ccb->nnc_datasize = datasize;
704 	ccb->nnc_secsize = secsize;
705 	ccb->nnc_blkno = blkno;
706 	ccb->nnc_done = nnc_done;
707 
708 	dmap = ccb->ccb_dmamap;
709 	error = bus_dmamap_load(sc->sc_dmat, dmap, data,
710 	    datasize, NULL,
711 	    (ISSET(flags, NVME_NS_CTX_F_POLL) ?
712 	      BUS_DMA_NOWAIT : BUS_DMA_WAITOK) |
713 	    (ISSET(flags, NVME_NS_CTX_F_READ) ?
714 	      BUS_DMA_READ : BUS_DMA_WRITE));
715 	if (error) {
716 		nvme_ccb_put(q, ccb);
717 		return error;
718 	}
719 
720 	bus_dmamap_sync(sc->sc_dmat, dmap, 0, dmap->dm_mapsize,
721 	    ISSET(flags, NVME_NS_CTX_F_READ) ?
722 	    BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
723 
724 	if (dmap->dm_nsegs > 2) {
725 		for (i = 1; i < dmap->dm_nsegs; i++) {
726 			htolem64(&ccb->ccb_prpl[i - 1],
727 			    dmap->dm_segs[i].ds_addr);
728 		}
729 		bus_dmamap_sync(sc->sc_dmat,
730 		    NVME_DMA_MAP(q->q_ccb_prpls),
731 		    ccb->ccb_prpl_off,
732 		    sizeof(*ccb->ccb_prpl) * (dmap->dm_nsegs - 1),
733 		    BUS_DMASYNC_PREWRITE);
734 	}
735 
736 	if (ISSET(flags, NVME_NS_CTX_F_POLL)) {
737 		if (nvme_poll(sc, q, ccb, nvme_ns_io_fill, NVME_TIMO_PT) != 0)
738 			return EIO;
739 		return 0;
740 	}
741 
742 	nvme_q_submit(sc, q, ccb, nvme_ns_io_fill);
743 	return 0;
744 }
745 
746 static void
747 nvme_ns_io_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
748 {
749 	struct nvme_sqe_io *sqe = slot;
750 	bus_dmamap_t dmap = ccb->ccb_dmamap;
751 
752 	sqe->opcode = ISSET(ccb->nnc_flags, NVME_NS_CTX_F_READ) ?
753 	    NVM_CMD_READ : NVM_CMD_WRITE;
754 	htolem32(&sqe->nsid, ccb->nnc_nsid);
755 
756 	htolem64(&sqe->entry.prp[0], dmap->dm_segs[0].ds_addr);
757 	switch (dmap->dm_nsegs) {
758 	case 1:
759 		break;
760 	case 2:
761 		htolem64(&sqe->entry.prp[1], dmap->dm_segs[1].ds_addr);
762 		break;
763 	default:
764 		/* the prp list is already set up and synced */
765 		htolem64(&sqe->entry.prp[1], ccb->ccb_prpl_dva);
766 		break;
767 	}
768 
769 	htolem64(&sqe->slba, ccb->nnc_blkno);
770 
771 	if (ISSET(ccb->nnc_flags, NVME_NS_CTX_F_FUA))
772 		htolem16(&sqe->ioflags, NVM_SQE_IO_FUA);
773 
774 	/* guaranteed by upper layers, but check just in case */
775 	KASSERT((ccb->nnc_datasize % ccb->nnc_secsize) == 0);
776 	htolem16(&sqe->nlb, (ccb->nnc_datasize / ccb->nnc_secsize) - 1);
777 }
778 
779 static void
780 nvme_ns_io_done(struct nvme_queue *q, struct nvme_ccb *ccb,
781     struct nvme_cqe *cqe)
782 {
783 	struct nvme_softc *sc = q->q_sc;
784 	bus_dmamap_t dmap = ccb->ccb_dmamap;
785 	void *nnc_cookie = ccb->ccb_cookie;
786 	nvme_nnc_done nnc_done = ccb->nnc_done;
787 	struct buf *bp = ccb->nnc_buf;
788 
789 	if (dmap->dm_nsegs > 2) {
790 		bus_dmamap_sync(sc->sc_dmat,
791 		    NVME_DMA_MAP(q->q_ccb_prpls),
792 		    ccb->ccb_prpl_off,
793 		    sizeof(*ccb->ccb_prpl) * (dmap->dm_nsegs - 1),
794 		    BUS_DMASYNC_POSTWRITE);
795 	}
796 
797 	bus_dmamap_sync(sc->sc_dmat, dmap, 0, dmap->dm_mapsize,
798 	    ISSET(ccb->nnc_flags, NVME_NS_CTX_F_READ) ?
799 	    BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
800 
801 	bus_dmamap_unload(sc->sc_dmat, dmap);
802 	nvme_ccb_put(q, ccb);
803 
804 	nnc_done(nnc_cookie, bp, lemtoh16(&cqe->flags), lemtoh32(&cqe->cdw0));
805 }
806 
807 /*
808  * If there is no volatile write cache, it makes no sense to issue
809  * flush commands or query for the status.
810  */
811 static bool
812 nvme_has_volatile_write_cache(struct nvme_softc *sc)
813 {
814 	/* sc_identify is filled during attachment */
815 	return  ((sc->sc_identify.vwc & NVME_ID_CTRLR_VWC_PRESENT) != 0);
816 }
817 
818 static bool
819 nvme_ns_sync_finished(void *cookie)
820 {
821 	int *result = cookie;
822 
823 	return (*result != 0);
824 }
825 
826 int
827 nvme_ns_sync(struct nvme_softc *sc, uint16_t nsid, int flags)
828 {
829 	struct nvme_queue *q = nvme_get_q(sc, NULL, true);
830 	struct nvme_ccb *ccb;
831 	int result = 0;
832 
833 	if (!nvme_has_volatile_write_cache(sc)) {
834 		/* cache not present, no value in trying to flush it */
835 		return 0;
836 	}
837 
838 	ccb = nvme_ccb_get(q, true);
839 	KASSERT(ccb != NULL);
840 
841 	ccb->ccb_done = nvme_ns_sync_done;
842 	ccb->ccb_cookie = &result;
843 
844 	/* namespace context */
845 	ccb->nnc_nsid = nsid;
846 	ccb->nnc_flags = flags;
847 	ccb->nnc_done = NULL;
848 
849 	if (ISSET(flags, NVME_NS_CTX_F_POLL)) {
850 		if (nvme_poll(sc, q, ccb, nvme_ns_sync_fill, NVME_TIMO_SY) != 0)
851 			return EIO;
852 		return 0;
853 	}
854 
855 	nvme_q_submit(sc, q, ccb, nvme_ns_sync_fill);
856 
857 	/* wait for completion */
858 	nvme_q_wait_complete(sc, q, nvme_ns_sync_finished, &result);
859 	KASSERT(result != 0);
860 
861 	return (result > 0) ? 0 : EIO;
862 }
863 
864 static void
865 nvme_ns_sync_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
866 {
867 	struct nvme_sqe *sqe = slot;
868 
869 	sqe->opcode = NVM_CMD_FLUSH;
870 	htolem32(&sqe->nsid, ccb->nnc_nsid);
871 }
872 
873 static void
874 nvme_ns_sync_done(struct nvme_queue *q, struct nvme_ccb *ccb,
875     struct nvme_cqe *cqe)
876 {
877 	int *result = ccb->ccb_cookie;
878 	uint16_t status = NVME_CQE_SC(lemtoh16(&cqe->flags));
879 
880 	if (status == NVME_CQE_SC_SUCCESS)
881 		*result = 1;
882 	else
883 		*result = -1;
884 
885 	nvme_ccb_put(q, ccb);
886 }
887 
888 static bool
889 nvme_getcache_finished(void *xc)
890 {
891 	int *addr = xc;
892 
893 	return (*addr != 0);
894 }
895 
896 /*
897  * Get status of volatile write cache. Always asynchronous.
898  */
899 int
900 nvme_admin_getcache(struct nvme_softc *sc, int *addr)
901 {
902 	struct nvme_ccb *ccb;
903 	struct nvme_queue *q = sc->sc_admin_q;
904 	int result = 0, error;
905 
906 	if (!nvme_has_volatile_write_cache(sc)) {
907 		/* cache simply not present */
908 		*addr = 0;
909 		return 0;
910 	}
911 
912 	ccb = nvme_ccb_get(q, true);
913 	KASSERT(ccb != NULL);
914 
915 	ccb->ccb_done = nvme_getcache_done;
916 	ccb->ccb_cookie = &result;
917 
918 	/* namespace context */
919 	ccb->nnc_flags = 0;
920 	ccb->nnc_done = NULL;
921 
922 	nvme_q_submit(sc, q, ccb, nvme_getcache_fill);
923 
924 	/* wait for completion */
925 	nvme_q_wait_complete(sc, q, nvme_getcache_finished, &result);
926 	KASSERT(result != 0);
927 
928 	if (result > 0) {
929 		*addr = result;
930 		error = 0;
931 	} else
932 		error = EINVAL;
933 
934 	return error;
935 }
936 
937 static void
938 nvme_getcache_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
939 {
940 	struct nvme_sqe *sqe = slot;
941 
942 	sqe->opcode = NVM_ADMIN_GET_FEATURES;
943 	htolem32(&sqe->cdw10, NVM_FEATURE_VOLATILE_WRITE_CACHE);
944 	htolem32(&sqe->cdw11, NVM_VOLATILE_WRITE_CACHE_WCE);
945 }
946 
947 static void
948 nvme_getcache_done(struct nvme_queue *q, struct nvme_ccb *ccb,
949     struct nvme_cqe *cqe)
950 {
951 	int *addr = ccb->ccb_cookie;
952 	uint16_t status = NVME_CQE_SC(lemtoh16(&cqe->flags));
953 	uint32_t cdw0 = lemtoh32(&cqe->cdw0);
954 	int result;
955 
956 	if (status == NVME_CQE_SC_SUCCESS) {
957 		result = 0;
958 
959 		/*
960 		 * DPO not supported, Dataset Management (DSM) field doesn't
961 		 * specify the same semantics. FUA is always supported.
962 		 */
963 		result = DKCACHE_FUA;
964 
965 		if (cdw0 & NVM_VOLATILE_WRITE_CACHE_WCE)
966 			result |= DKCACHE_WRITE;
967 
968 		/*
969 		 * If volatile write cache is present, the flag shall also be
970 		 * settable.
971 		 */
972 		result |= DKCACHE_WCHANGE;
973 
974 		/*
975 		 * ONCS field indicates whether the optional SAVE is also
976 		 * supported for Set Features. According to spec v1.3,
977 		 * Volatile Write Cache however doesn't support persistency
978 		 * across power cycle/reset.
979 		 */
980 
981 	} else {
982 		result = -1;
983 	}
984 
985 	*addr = result;
986 
987 	nvme_ccb_put(q, ccb);
988 }
989 
990 struct nvme_setcache_state {
991 	int dkcache;
992 	int result;
993 };
994 
995 static bool
996 nvme_setcache_finished(void *xc)
997 {
998 	struct nvme_setcache_state *st = xc;
999 
1000 	return (st->result != 0);
1001 }
1002 
1003 static void
1004 nvme_setcache_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
1005 {
1006 	struct nvme_sqe *sqe = slot;
1007 	struct nvme_setcache_state *st = ccb->ccb_cookie;
1008 
1009 	sqe->opcode = NVM_ADMIN_SET_FEATURES;
1010 	htolem32(&sqe->cdw10, NVM_FEATURE_VOLATILE_WRITE_CACHE);
1011 	if (st->dkcache & DKCACHE_WRITE)
1012 		htolem32(&sqe->cdw11, NVM_VOLATILE_WRITE_CACHE_WCE);
1013 }
1014 
1015 static void
1016 nvme_setcache_done(struct nvme_queue *q, struct nvme_ccb *ccb,
1017     struct nvme_cqe *cqe)
1018 {
1019 	struct nvme_setcache_state *st = ccb->ccb_cookie;
1020 	uint16_t status = NVME_CQE_SC(lemtoh16(&cqe->flags));
1021 
1022 	if (status == NVME_CQE_SC_SUCCESS) {
1023 		st->result = 1;
1024 	} else {
1025 		st->result = -1;
1026 	}
1027 
1028 	nvme_ccb_put(q, ccb);
1029 }
1030 
1031 /*
1032  * Set status of volatile write cache. Always asynchronous.
1033  */
1034 int
1035 nvme_admin_setcache(struct nvme_softc *sc, int dkcache)
1036 {
1037 	struct nvme_ccb *ccb;
1038 	struct nvme_queue *q = sc->sc_admin_q;
1039 	int error;
1040 	struct nvme_setcache_state st;
1041 
1042 	if (!nvme_has_volatile_write_cache(sc)) {
1043 		/* cache simply not present */
1044 		return EOPNOTSUPP;
1045 	}
1046 
1047 	if (dkcache & ~(DKCACHE_WRITE)) {
1048 		/* unsupported parameters */
1049 		return EOPNOTSUPP;
1050 	}
1051 
1052 	ccb = nvme_ccb_get(q, true);
1053 	KASSERT(ccb != NULL);
1054 
1055 	memset(&st, 0, sizeof(st));
1056 	st.dkcache = dkcache;
1057 
1058 	ccb->ccb_done = nvme_setcache_done;
1059 	ccb->ccb_cookie = &st;
1060 
1061 	/* namespace context */
1062 	ccb->nnc_flags = 0;
1063 	ccb->nnc_done = NULL;
1064 
1065 	nvme_q_submit(sc, q, ccb, nvme_setcache_fill);
1066 
1067 	/* wait for completion */
1068 	nvme_q_wait_complete(sc, q, nvme_setcache_finished, &st);
1069 	KASSERT(st.result != 0);
1070 
1071 	if (st.result > 0)
1072 		error = 0;
1073 	else
1074 		error = EINVAL;
1075 
1076 	return error;
1077 }
1078 
1079 void
1080 nvme_ns_free(struct nvme_softc *sc, uint16_t nsid)
1081 {
1082 	struct nvme_namespace *ns;
1083 	struct nvm_identify_namespace *identify;
1084 
1085 	ns = nvme_ns_get(sc, nsid);
1086 	KASSERT(ns);
1087 
1088 	identify = ns->ident;
1089 	ns->ident = NULL;
1090 	if (identify != NULL)
1091 		kmem_free(identify, sizeof(*identify));
1092 }
1093 
1094 struct nvme_pt_state {
1095 	struct nvme_pt_command *pt;
1096 	bool finished;
1097 };
1098 
1099 static void
1100 nvme_pt_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
1101 {
1102 	struct nvme_softc *sc = q->q_sc;
1103 	struct nvme_sqe *sqe = slot;
1104 	struct nvme_pt_state *state = ccb->ccb_cookie;
1105 	struct nvme_pt_command *pt = state->pt;
1106 	bus_dmamap_t dmap = ccb->ccb_dmamap;
1107 	int i;
1108 
1109 	sqe->opcode = pt->cmd.opcode;
1110 	htolem32(&sqe->nsid, pt->cmd.nsid);
1111 
1112 	if (pt->buf != NULL && pt->len > 0) {
1113 		htolem64(&sqe->entry.prp[0], dmap->dm_segs[0].ds_addr);
1114 		switch (dmap->dm_nsegs) {
1115 		case 1:
1116 			break;
1117 		case 2:
1118 			htolem64(&sqe->entry.prp[1], dmap->dm_segs[1].ds_addr);
1119 			break;
1120 		default:
1121 			for (i = 1; i < dmap->dm_nsegs; i++) {
1122 				htolem64(&ccb->ccb_prpl[i - 1],
1123 				    dmap->dm_segs[i].ds_addr);
1124 			}
1125 			bus_dmamap_sync(sc->sc_dmat,
1126 			    NVME_DMA_MAP(q->q_ccb_prpls),
1127 			    ccb->ccb_prpl_off,
1128 			    sizeof(*ccb->ccb_prpl) * (dmap->dm_nsegs - 1),
1129 			    BUS_DMASYNC_PREWRITE);
1130 			htolem64(&sqe->entry.prp[1], ccb->ccb_prpl_dva);
1131 			break;
1132 		}
1133 	}
1134 
1135 	htolem32(&sqe->cdw10, pt->cmd.cdw10);
1136 	htolem32(&sqe->cdw11, pt->cmd.cdw11);
1137 	htolem32(&sqe->cdw12, pt->cmd.cdw12);
1138 	htolem32(&sqe->cdw13, pt->cmd.cdw13);
1139 	htolem32(&sqe->cdw14, pt->cmd.cdw14);
1140 	htolem32(&sqe->cdw15, pt->cmd.cdw15);
1141 }
1142 
1143 static void
1144 nvme_pt_done(struct nvme_queue *q, struct nvme_ccb *ccb, struct nvme_cqe *cqe)
1145 {
1146 	struct nvme_softc *sc = q->q_sc;
1147 	struct nvme_pt_state *state = ccb->ccb_cookie;
1148 	struct nvme_pt_command *pt = state->pt;
1149 	bus_dmamap_t dmap = ccb->ccb_dmamap;
1150 
1151 	if (pt->buf != NULL && pt->len > 0) {
1152 		if (dmap->dm_nsegs > 2) {
1153 			bus_dmamap_sync(sc->sc_dmat,
1154 			    NVME_DMA_MAP(q->q_ccb_prpls),
1155 			    ccb->ccb_prpl_off,
1156 			    sizeof(*ccb->ccb_prpl) * (dmap->dm_nsegs - 1),
1157 			    BUS_DMASYNC_POSTWRITE);
1158 		}
1159 
1160 		bus_dmamap_sync(sc->sc_dmat, dmap, 0, dmap->dm_mapsize,
1161 		    pt->is_read ? BUS_DMASYNC_POSTREAD : BUS_DMASYNC_POSTWRITE);
1162 		bus_dmamap_unload(sc->sc_dmat, dmap);
1163 	}
1164 
1165 	pt->cpl.cdw0 = lemtoh32(&cqe->cdw0);
1166 	pt->cpl.flags = lemtoh16(&cqe->flags) & ~NVME_CQE_PHASE;
1167 
1168 	state->finished = true;
1169 
1170 	nvme_ccb_put(q, ccb);
1171 }
1172 
1173 static bool
1174 nvme_pt_finished(void *cookie)
1175 {
1176 	struct nvme_pt_state *state = cookie;
1177 
1178 	return state->finished;
1179 }
1180 
1181 static int
1182 nvme_command_passthrough(struct nvme_softc *sc, struct nvme_pt_command *pt,
1183     uint16_t nsid, struct lwp *l, bool is_adminq)
1184 {
1185 	struct nvme_queue *q;
1186 	struct nvme_ccb *ccb;
1187 	void *buf = NULL;
1188 	struct nvme_pt_state state;
1189 	int error;
1190 
1191 	/* limit command size to maximum data transfer size */
1192 	if ((pt->buf == NULL && pt->len > 0) ||
1193 	    (pt->buf != NULL && (pt->len == 0 || pt->len > sc->sc_mdts)))
1194 		return EINVAL;
1195 
1196 	q = is_adminq ? sc->sc_admin_q : nvme_get_q(sc, NULL, true);
1197 	ccb = nvme_ccb_get(q, true);
1198 	KASSERT(ccb != NULL);
1199 
1200 	if (pt->buf != NULL) {
1201 		KASSERT(pt->len > 0);
1202 		buf = kmem_alloc(pt->len, KM_SLEEP);
1203 		if (!pt->is_read) {
1204 			error = copyin(pt->buf, buf, pt->len);
1205 			if (error)
1206 				goto kmem_free;
1207 		}
1208 		error = bus_dmamap_load(sc->sc_dmat, ccb->ccb_dmamap, buf,
1209 		    pt->len, NULL,
1210 		    BUS_DMA_WAITOK |
1211 		      (pt->is_read ? BUS_DMA_READ : BUS_DMA_WRITE));
1212 		if (error)
1213 			goto kmem_free;
1214 		bus_dmamap_sync(sc->sc_dmat, ccb->ccb_dmamap,
1215 		    0, ccb->ccb_dmamap->dm_mapsize,
1216 		    pt->is_read ? BUS_DMASYNC_PREREAD : BUS_DMASYNC_PREWRITE);
1217 	}
1218 
1219 	memset(&state, 0, sizeof(state));
1220 	state.pt = pt;
1221 	state.finished = false;
1222 
1223 	ccb->ccb_done = nvme_pt_done;
1224 	ccb->ccb_cookie = &state;
1225 
1226 	pt->cmd.nsid = nsid;
1227 
1228 	nvme_q_submit(sc, q, ccb, nvme_pt_fill);
1229 
1230 	/* wait for completion */
1231 	nvme_q_wait_complete(sc, q, nvme_pt_finished, &state);
1232 	KASSERT(state.finished);
1233 
1234 	error = 0;
1235 
1236 	if (buf != NULL) {
1237 		if (error == 0 && pt->is_read)
1238 			error = copyout(buf, pt->buf, pt->len);
1239 kmem_free:
1240 		kmem_free(buf, pt->len);
1241 	}
1242 
1243 	return error;
1244 }
1245 
1246 static void
1247 nvme_q_submit(struct nvme_softc *sc, struct nvme_queue *q, struct nvme_ccb *ccb,
1248     void (*fill)(struct nvme_queue *, struct nvme_ccb *, void *))
1249 {
1250 	struct nvme_sqe *sqe = NVME_DMA_KVA(q->q_sq_dmamem);
1251 	uint32_t tail;
1252 
1253 	mutex_enter(&q->q_sq_mtx);
1254 	tail = q->q_sq_tail;
1255 	if (++q->q_sq_tail >= q->q_entries)
1256 		q->q_sq_tail = 0;
1257 
1258 	sqe += tail;
1259 
1260 	bus_dmamap_sync(sc->sc_dmat, NVME_DMA_MAP(q->q_sq_dmamem),
1261 	    sizeof(*sqe) * tail, sizeof(*sqe), BUS_DMASYNC_POSTWRITE);
1262 	memset(sqe, 0, sizeof(*sqe));
1263 	(*fill)(q, ccb, sqe);
1264 	htolem16(&sqe->cid, ccb->ccb_id);
1265 	bus_dmamap_sync(sc->sc_dmat, NVME_DMA_MAP(q->q_sq_dmamem),
1266 	    sizeof(*sqe) * tail, sizeof(*sqe), BUS_DMASYNC_PREWRITE);
1267 
1268 	nvme_write4(sc, q->q_sqtdbl, q->q_sq_tail);
1269 	mutex_exit(&q->q_sq_mtx);
1270 }
1271 
1272 struct nvme_poll_state {
1273 	struct nvme_sqe s;
1274 	struct nvme_cqe c;
1275 	void *cookie;
1276 	void (*done)(struct nvme_queue *, struct nvme_ccb *, struct nvme_cqe *);
1277 };
1278 
1279 static int
1280 nvme_poll(struct nvme_softc *sc, struct nvme_queue *q, struct nvme_ccb *ccb,
1281     void (*fill)(struct nvme_queue *, struct nvme_ccb *, void *), int timo_sec)
1282 {
1283 	struct nvme_poll_state state;
1284 	uint16_t flags;
1285 	int step = 10;
1286 	int maxloop = timo_sec * 1000000 / step;
1287 	int error = 0;
1288 
1289 	memset(&state, 0, sizeof(state));
1290 	(*fill)(q, ccb, &state.s);
1291 
1292 	state.done = ccb->ccb_done;
1293 	state.cookie = ccb->ccb_cookie;
1294 
1295 	ccb->ccb_done = nvme_poll_done;
1296 	ccb->ccb_cookie = &state;
1297 
1298 	nvme_q_submit(sc, q, ccb, nvme_poll_fill);
1299 	while (!ISSET(state.c.flags, htole16(NVME_CQE_PHASE))) {
1300 		if (nvme_q_complete(sc, q) == 0)
1301 			delay(step);
1302 
1303 		if (timo_sec >= 0 && --maxloop <= 0) {
1304 			error = ETIMEDOUT;
1305 			break;
1306 		}
1307 	}
1308 
1309 	if (error == 0) {
1310 		flags = lemtoh16(&state.c.flags);
1311 		return flags & ~NVME_CQE_PHASE;
1312 	} else {
1313 		/*
1314 		 * If it succeds later, it would hit ccb which will have been
1315 		 * already reused for something else. Not good. Cross
1316 		 * fingers and hope for best. XXX do controller reset?
1317 		 */
1318 		aprint_error_dev(sc->sc_dev, "polled command timed out\n");
1319 
1320 		/* Invoke the callback to clean state anyway */
1321 		struct nvme_cqe cqe;
1322 		memset(&cqe, 0, sizeof(cqe));
1323 		ccb->ccb_done(q, ccb, &cqe);
1324 
1325 		return 1;
1326 	}
1327 }
1328 
1329 static void
1330 nvme_poll_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
1331 {
1332 	struct nvme_sqe *sqe = slot;
1333 	struct nvme_poll_state *state = ccb->ccb_cookie;
1334 
1335 	*sqe = state->s;
1336 }
1337 
1338 static void
1339 nvme_poll_done(struct nvme_queue *q, struct nvme_ccb *ccb,
1340     struct nvme_cqe *cqe)
1341 {
1342 	struct nvme_poll_state *state = ccb->ccb_cookie;
1343 
1344 	state->c = *cqe;
1345 	SET(state->c.flags, htole16(NVME_CQE_PHASE));
1346 
1347 	ccb->ccb_cookie = state->cookie;
1348 	state->done(q, ccb, &state->c);
1349 }
1350 
1351 static void
1352 nvme_sqe_fill(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
1353 {
1354 	struct nvme_sqe *src = ccb->ccb_cookie;
1355 	struct nvme_sqe *dst = slot;
1356 
1357 	*dst = *src;
1358 }
1359 
1360 static void
1361 nvme_empty_done(struct nvme_queue *q, struct nvme_ccb *ccb,
1362     struct nvme_cqe *cqe)
1363 {
1364 }
1365 
1366 static int
1367 nvme_q_complete(struct nvme_softc *sc, struct nvme_queue *q)
1368 {
1369 	struct nvme_ccb *ccb;
1370 	struct nvme_cqe *ring = NVME_DMA_KVA(q->q_cq_dmamem), *cqe;
1371 	uint16_t flags;
1372 	int rv = 0;
1373 
1374 	mutex_enter(&q->q_cq_mtx);
1375 
1376 	nvme_dmamem_sync(sc, q->q_cq_dmamem, BUS_DMASYNC_POSTREAD);
1377 	for (;;) {
1378 		cqe = &ring[q->q_cq_head];
1379 		flags = lemtoh16(&cqe->flags);
1380 		if ((flags & NVME_CQE_PHASE) != q->q_cq_phase)
1381 			break;
1382 
1383 		ccb = &q->q_ccbs[lemtoh16(&cqe->cid)];
1384 
1385 		if (++q->q_cq_head >= q->q_entries) {
1386 			q->q_cq_head = 0;
1387 			q->q_cq_phase ^= NVME_CQE_PHASE;
1388 		}
1389 
1390 #ifdef DEBUG
1391 		/*
1392 		 * If we get spurious completion notification, something
1393 		 * is seriously hosed up. Very likely DMA to some random
1394 		 * memory place happened, so just bail out.
1395 		 */
1396 		if ((intptr_t)ccb->ccb_cookie == NVME_CCB_FREE) {
1397 			panic("%s: invalid ccb detected",
1398 			    device_xname(sc->sc_dev));
1399 			/* NOTREACHED */
1400 		}
1401 #endif
1402 
1403 		rv++;
1404 
1405 		/*
1406 		 * Unlock the mutex before calling the ccb_done callback
1407 		 * and re-lock afterwards. The callback triggers lddone()
1408 		 * which schedules another i/o, and also calls nvme_ccb_put().
1409 		 * Unlock/relock avoids possibility of deadlock.
1410 		 */
1411 		mutex_exit(&q->q_cq_mtx);
1412 		ccb->ccb_done(q, ccb, cqe);
1413 		mutex_enter(&q->q_cq_mtx);
1414 	}
1415 	nvme_dmamem_sync(sc, q->q_cq_dmamem, BUS_DMASYNC_PREREAD);
1416 
1417 	if (rv)
1418 		nvme_write4(sc, q->q_cqhdbl, q->q_cq_head);
1419 
1420 	mutex_exit(&q->q_cq_mtx);
1421 
1422 	return rv;
1423 }
1424 
1425 static void
1426 nvme_q_wait_complete(struct nvme_softc *sc,
1427     struct nvme_queue *q, bool (*finished)(void *), void *cookie)
1428 {
1429 	mutex_enter(&q->q_ccb_mtx);
1430 	if (finished(cookie))
1431 		goto out;
1432 
1433 	for(;;) {
1434 		q->q_ccb_waiting = true;
1435 		cv_wait(&q->q_ccb_wait, &q->q_ccb_mtx);
1436 
1437 		if (finished(cookie))
1438 			break;
1439 	}
1440 
1441 out:
1442 	mutex_exit(&q->q_ccb_mtx);
1443 }
1444 
1445 static int
1446 nvme_identify(struct nvme_softc *sc, u_int mps)
1447 {
1448 	char sn[41], mn[81], fr[17];
1449 	struct nvm_identify_controller *identify;
1450 	struct nvme_dmamem *mem;
1451 	struct nvme_ccb *ccb;
1452 	u_int mdts;
1453 	int rv = 1;
1454 
1455 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
1456 	KASSERT(ccb != NULL); /* it's a bug if we don't have spare ccb here */
1457 
1458 	mem = nvme_dmamem_alloc(sc, sizeof(*identify));
1459 	if (mem == NULL)
1460 		return 1;
1461 
1462 	ccb->ccb_done = nvme_empty_done;
1463 	ccb->ccb_cookie = mem;
1464 
1465 	nvme_dmamem_sync(sc, mem, BUS_DMASYNC_PREREAD);
1466 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_fill_identify,
1467 	    NVME_TIMO_IDENT);
1468 	nvme_dmamem_sync(sc, mem, BUS_DMASYNC_POSTREAD);
1469 
1470 	nvme_ccb_put(sc->sc_admin_q, ccb);
1471 
1472 	if (rv != 0)
1473 		goto done;
1474 
1475 	identify = NVME_DMA_KVA(mem);
1476 	sc->sc_identify = *identify;
1477 	identify = NULL;
1478 
1479 	/* Convert data to host endian */
1480 	nvme_identify_controller_swapbytes(&sc->sc_identify);
1481 
1482 	strnvisx(sn, sizeof(sn), (const char *)sc->sc_identify.sn,
1483 	    sizeof(sc->sc_identify.sn), VIS_TRIM|VIS_SAFE|VIS_OCTAL);
1484 	strnvisx(mn, sizeof(mn), (const char *)sc->sc_identify.mn,
1485 	    sizeof(sc->sc_identify.mn), VIS_TRIM|VIS_SAFE|VIS_OCTAL);
1486 	strnvisx(fr, sizeof(fr), (const char *)sc->sc_identify.fr,
1487 	    sizeof(sc->sc_identify.fr), VIS_TRIM|VIS_SAFE|VIS_OCTAL);
1488 	aprint_normal_dev(sc->sc_dev, "%s, firmware %s, serial %s\n", mn, fr,
1489 	    sn);
1490 
1491 	strlcpy(sc->sc_modelname, mn, sizeof(sc->sc_modelname));
1492 
1493 	if (sc->sc_identify.mdts > 0) {
1494 		mdts = (1 << sc->sc_identify.mdts) * (1 << mps);
1495 		if (mdts < sc->sc_mdts)
1496 			sc->sc_mdts = mdts;
1497 	}
1498 
1499 	sc->sc_nn = sc->sc_identify.nn;
1500 
1501 done:
1502 	nvme_dmamem_free(sc, mem);
1503 
1504 	return rv;
1505 }
1506 
1507 static int
1508 nvme_q_create(struct nvme_softc *sc, struct nvme_queue *q)
1509 {
1510 	struct nvme_sqe_q sqe;
1511 	struct nvme_ccb *ccb;
1512 	int rv;
1513 
1514 	if (sc->sc_use_mq && sc->sc_intr_establish(sc, q->q_id, q) != 0)
1515 		return 1;
1516 
1517 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
1518 	KASSERT(ccb != NULL);
1519 
1520 	ccb->ccb_done = nvme_empty_done;
1521 	ccb->ccb_cookie = &sqe;
1522 
1523 	memset(&sqe, 0, sizeof(sqe));
1524 	sqe.opcode = NVM_ADMIN_ADD_IOCQ;
1525 	htolem64(&sqe.prp1, NVME_DMA_DVA(q->q_cq_dmamem));
1526 	htolem16(&sqe.qsize, q->q_entries - 1);
1527 	htolem16(&sqe.qid, q->q_id);
1528 	sqe.qflags = NVM_SQE_CQ_IEN | NVM_SQE_Q_PC;
1529 	if (sc->sc_use_mq)
1530 		htolem16(&sqe.cqid, q->q_id);	/* qid == vector */
1531 
1532 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_QOP);
1533 	if (rv != 0)
1534 		goto fail;
1535 
1536 	ccb->ccb_done = nvme_empty_done;
1537 	ccb->ccb_cookie = &sqe;
1538 
1539 	memset(&sqe, 0, sizeof(sqe));
1540 	sqe.opcode = NVM_ADMIN_ADD_IOSQ;
1541 	htolem64(&sqe.prp1, NVME_DMA_DVA(q->q_sq_dmamem));
1542 	htolem16(&sqe.qsize, q->q_entries - 1);
1543 	htolem16(&sqe.qid, q->q_id);
1544 	htolem16(&sqe.cqid, q->q_id);
1545 	sqe.qflags = NVM_SQE_Q_PC;
1546 
1547 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_QOP);
1548 	if (rv != 0)
1549 		goto fail;
1550 
1551 	nvme_ccb_put(sc->sc_admin_q, ccb);
1552 	return 0;
1553 
1554 fail:
1555 	if (sc->sc_use_mq)
1556 		sc->sc_intr_disestablish(sc, q->q_id);
1557 
1558 	nvme_ccb_put(sc->sc_admin_q, ccb);
1559 	return rv;
1560 }
1561 
1562 static int
1563 nvme_q_delete(struct nvme_softc *sc, struct nvme_queue *q)
1564 {
1565 	struct nvme_sqe_q sqe;
1566 	struct nvme_ccb *ccb;
1567 	int rv;
1568 
1569 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
1570 	KASSERT(ccb != NULL);
1571 
1572 	ccb->ccb_done = nvme_empty_done;
1573 	ccb->ccb_cookie = &sqe;
1574 
1575 	memset(&sqe, 0, sizeof(sqe));
1576 	sqe.opcode = NVM_ADMIN_DEL_IOSQ;
1577 	htolem16(&sqe.qid, q->q_id);
1578 
1579 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_QOP);
1580 	if (rv != 0)
1581 		goto fail;
1582 
1583 	ccb->ccb_done = nvme_empty_done;
1584 	ccb->ccb_cookie = &sqe;
1585 
1586 	memset(&sqe, 0, sizeof(sqe));
1587 	sqe.opcode = NVM_ADMIN_DEL_IOCQ;
1588 	htolem16(&sqe.qid, q->q_id);
1589 
1590 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_sqe_fill, NVME_TIMO_QOP);
1591 	if (rv != 0)
1592 		goto fail;
1593 
1594 fail:
1595 	nvme_ccb_put(sc->sc_admin_q, ccb);
1596 
1597 	if (rv == 0 && sc->sc_use_mq) {
1598 		if (sc->sc_intr_disestablish(sc, q->q_id))
1599 			rv = 1;
1600 	}
1601 
1602 	return rv;
1603 }
1604 
1605 static void
1606 nvme_fill_identify(struct nvme_queue *q, struct nvme_ccb *ccb, void *slot)
1607 {
1608 	struct nvme_sqe *sqe = slot;
1609 	struct nvme_dmamem *mem = ccb->ccb_cookie;
1610 
1611 	sqe->opcode = NVM_ADMIN_IDENTIFY;
1612 	htolem64(&sqe->entry.prp[0], NVME_DMA_DVA(mem));
1613 	htolem32(&sqe->cdw10, 1);
1614 }
1615 
1616 static int
1617 nvme_set_number_of_queues(struct nvme_softc *sc, u_int nq, u_int *ncqa,
1618     u_int *nsqa)
1619 {
1620 	struct nvme_pt_state state;
1621 	struct nvme_pt_command pt;
1622 	struct nvme_ccb *ccb;
1623 	int rv;
1624 
1625 	ccb = nvme_ccb_get(sc->sc_admin_q, false);
1626 	KASSERT(ccb != NULL); /* it's a bug if we don't have spare ccb here */
1627 
1628 	memset(&pt, 0, sizeof(pt));
1629 	pt.cmd.opcode = NVM_ADMIN_SET_FEATURES;
1630 	pt.cmd.cdw10 = NVM_FEATURE_NUMBER_OF_QUEUES;
1631 	pt.cmd.cdw11 = ((nq - 1) << 16) | (nq - 1);
1632 
1633 	memset(&state, 0, sizeof(state));
1634 	state.pt = &pt;
1635 	state.finished = false;
1636 
1637 	ccb->ccb_done = nvme_pt_done;
1638 	ccb->ccb_cookie = &state;
1639 
1640 	rv = nvme_poll(sc, sc->sc_admin_q, ccb, nvme_pt_fill, NVME_TIMO_QOP);
1641 
1642 	if (rv != 0) {
1643 		*ncqa = *nsqa = 0;
1644 		return EIO;
1645 	}
1646 
1647 	*ncqa = (pt.cpl.cdw0 >> 16) + 1;
1648 	*nsqa = (pt.cpl.cdw0 & 0xffff) + 1;
1649 
1650 	return 0;
1651 }
1652 
1653 static int
1654 nvme_ccbs_alloc(struct nvme_queue *q, uint16_t nccbs)
1655 {
1656 	struct nvme_softc *sc = q->q_sc;
1657 	struct nvme_ccb *ccb;
1658 	bus_addr_t off;
1659 	uint64_t *prpl;
1660 	u_int i;
1661 
1662 	mutex_init(&q->q_ccb_mtx, MUTEX_DEFAULT, IPL_BIO);
1663 	cv_init(&q->q_ccb_wait, "nvmeqw");
1664 	q->q_ccb_waiting = false;
1665 	SIMPLEQ_INIT(&q->q_ccb_list);
1666 
1667 	q->q_ccbs = kmem_alloc(sizeof(*ccb) * nccbs, KM_SLEEP);
1668 
1669 	q->q_nccbs = nccbs;
1670 	q->q_ccb_prpls = nvme_dmamem_alloc(sc,
1671 	    sizeof(*prpl) * sc->sc_max_sgl * nccbs);
1672 
1673 	prpl = NVME_DMA_KVA(q->q_ccb_prpls);
1674 	off = 0;
1675 
1676 	for (i = 0; i < nccbs; i++) {
1677 		ccb = &q->q_ccbs[i];
1678 
1679 		if (bus_dmamap_create(sc->sc_dmat, sc->sc_mdts,
1680 		    sc->sc_max_sgl + 1 /* we get a free prp in the sqe */,
1681 		    sc->sc_mps, sc->sc_mps, BUS_DMA_WAITOK | BUS_DMA_ALLOCNOW,
1682 		    &ccb->ccb_dmamap) != 0)
1683 			goto free_maps;
1684 
1685 		ccb->ccb_id = i;
1686 		ccb->ccb_prpl = prpl;
1687 		ccb->ccb_prpl_off = off;
1688 		ccb->ccb_prpl_dva = NVME_DMA_DVA(q->q_ccb_prpls) + off;
1689 
1690 		SIMPLEQ_INSERT_TAIL(&q->q_ccb_list, ccb, ccb_entry);
1691 
1692 		prpl += sc->sc_max_sgl;
1693 		off += sizeof(*prpl) * sc->sc_max_sgl;
1694 	}
1695 
1696 	return 0;
1697 
1698 free_maps:
1699 	nvme_ccbs_free(q);
1700 	return 1;
1701 }
1702 
1703 static struct nvme_ccb *
1704 nvme_ccb_get(struct nvme_queue *q, bool wait)
1705 {
1706 	struct nvme_ccb *ccb = NULL;
1707 
1708 	mutex_enter(&q->q_ccb_mtx);
1709 again:
1710 	ccb = SIMPLEQ_FIRST(&q->q_ccb_list);
1711 	if (ccb != NULL) {
1712 		SIMPLEQ_REMOVE_HEAD(&q->q_ccb_list, ccb_entry);
1713 #ifdef DEBUG
1714 		ccb->ccb_cookie = NULL;
1715 #endif
1716 	} else {
1717 		if (__predict_false(wait)) {
1718 			q->q_ccb_waiting = true;
1719 			cv_wait(&q->q_ccb_wait, &q->q_ccb_mtx);
1720 			goto again;
1721 		}
1722 	}
1723 	mutex_exit(&q->q_ccb_mtx);
1724 
1725 	return ccb;
1726 }
1727 
1728 static void
1729 nvme_ccb_put(struct nvme_queue *q, struct nvme_ccb *ccb)
1730 {
1731 
1732 	mutex_enter(&q->q_ccb_mtx);
1733 #ifdef DEBUG
1734 	ccb->ccb_cookie = (void *)NVME_CCB_FREE;
1735 #endif
1736 	SIMPLEQ_INSERT_HEAD(&q->q_ccb_list, ccb, ccb_entry);
1737 
1738 	/* It's unlikely there are any waiters, it's not used for regular I/O */
1739 	if (__predict_false(q->q_ccb_waiting)) {
1740 		q->q_ccb_waiting = false;
1741 		cv_broadcast(&q->q_ccb_wait);
1742 	}
1743 
1744 	mutex_exit(&q->q_ccb_mtx);
1745 }
1746 
1747 static void
1748 nvme_ccbs_free(struct nvme_queue *q)
1749 {
1750 	struct nvme_softc *sc = q->q_sc;
1751 	struct nvme_ccb *ccb;
1752 
1753 	mutex_enter(&q->q_ccb_mtx);
1754 	while ((ccb = SIMPLEQ_FIRST(&q->q_ccb_list)) != NULL) {
1755 		SIMPLEQ_REMOVE_HEAD(&q->q_ccb_list, ccb_entry);
1756 		/*
1757 		 * bus_dmamap_destroy() may call vm_map_lock() and rw_enter()
1758 		 * internally. don't hold spin mutex
1759 		 */
1760 		mutex_exit(&q->q_ccb_mtx);
1761 		bus_dmamap_destroy(sc->sc_dmat, ccb->ccb_dmamap);
1762 		mutex_enter(&q->q_ccb_mtx);
1763 	}
1764 	mutex_exit(&q->q_ccb_mtx);
1765 
1766 	nvme_dmamem_free(sc, q->q_ccb_prpls);
1767 	kmem_free(q->q_ccbs, sizeof(*ccb) * q->q_nccbs);
1768 	q->q_ccbs = NULL;
1769 	cv_destroy(&q->q_ccb_wait);
1770 	mutex_destroy(&q->q_ccb_mtx);
1771 }
1772 
1773 static struct nvme_queue *
1774 nvme_q_alloc(struct nvme_softc *sc, uint16_t id, u_int entries, u_int dstrd)
1775 {
1776 	struct nvme_queue *q;
1777 
1778 	q = kmem_alloc(sizeof(*q), KM_SLEEP);
1779 	q->q_sc = sc;
1780 	q->q_sq_dmamem = nvme_dmamem_alloc(sc,
1781 	    sizeof(struct nvme_sqe) * entries);
1782 	if (q->q_sq_dmamem == NULL)
1783 		goto free;
1784 
1785 	q->q_cq_dmamem = nvme_dmamem_alloc(sc,
1786 	    sizeof(struct nvme_cqe) * entries);
1787 	if (q->q_cq_dmamem == NULL)
1788 		goto free_sq;
1789 
1790 	memset(NVME_DMA_KVA(q->q_sq_dmamem), 0, NVME_DMA_LEN(q->q_sq_dmamem));
1791 	memset(NVME_DMA_KVA(q->q_cq_dmamem), 0, NVME_DMA_LEN(q->q_cq_dmamem));
1792 
1793 	mutex_init(&q->q_sq_mtx, MUTEX_DEFAULT, IPL_BIO);
1794 	mutex_init(&q->q_cq_mtx, MUTEX_DEFAULT, IPL_BIO);
1795 	q->q_sqtdbl = NVME_SQTDBL(id, dstrd);
1796 	q->q_cqhdbl = NVME_CQHDBL(id, dstrd);
1797 	q->q_id = id;
1798 	q->q_entries = entries;
1799 	q->q_sq_tail = 0;
1800 	q->q_cq_head = 0;
1801 	q->q_cq_phase = NVME_CQE_PHASE;
1802 
1803 	nvme_dmamem_sync(sc, q->q_sq_dmamem, BUS_DMASYNC_PREWRITE);
1804 	nvme_dmamem_sync(sc, q->q_cq_dmamem, BUS_DMASYNC_PREREAD);
1805 
1806 	/*
1807 	 * Due to definition of full and empty queue (queue is empty
1808 	 * when head == tail, full when tail is one less then head),
1809 	 * we can actually only have (entries - 1) in-flight commands.
1810 	 */
1811 	if (nvme_ccbs_alloc(q, entries - 1) != 0) {
1812 		aprint_error_dev(sc->sc_dev, "unable to allocate ccbs\n");
1813 		goto free_cq;
1814 	}
1815 
1816 	return q;
1817 
1818 free_cq:
1819 	nvme_dmamem_free(sc, q->q_cq_dmamem);
1820 free_sq:
1821 	nvme_dmamem_free(sc, q->q_sq_dmamem);
1822 free:
1823 	kmem_free(q, sizeof(*q));
1824 
1825 	return NULL;
1826 }
1827 
1828 static void
1829 nvme_q_free(struct nvme_softc *sc, struct nvme_queue *q)
1830 {
1831 	nvme_ccbs_free(q);
1832 	mutex_destroy(&q->q_sq_mtx);
1833 	mutex_destroy(&q->q_cq_mtx);
1834 	nvme_dmamem_sync(sc, q->q_cq_dmamem, BUS_DMASYNC_POSTREAD);
1835 	nvme_dmamem_sync(sc, q->q_sq_dmamem, BUS_DMASYNC_POSTWRITE);
1836 	nvme_dmamem_free(sc, q->q_cq_dmamem);
1837 	nvme_dmamem_free(sc, q->q_sq_dmamem);
1838 	kmem_free(q, sizeof(*q));
1839 }
1840 
1841 int
1842 nvme_intr(void *xsc)
1843 {
1844 	struct nvme_softc *sc = xsc;
1845 
1846 	/*
1847 	 * INTx is level triggered, controller deasserts the interrupt only
1848 	 * when we advance command queue head via write to the doorbell.
1849 	 * Tell the controller to block the interrupts while we process
1850 	 * the queue(s).
1851 	 */
1852 	nvme_write4(sc, NVME_INTMS, 1);
1853 
1854 	softint_schedule(sc->sc_softih[0]);
1855 
1856 	/* don't know, might not have been for us */
1857 	return 1;
1858 }
1859 
1860 void
1861 nvme_softintr_intx(void *xq)
1862 {
1863 	struct nvme_queue *q = xq;
1864 	struct nvme_softc *sc = q->q_sc;
1865 
1866 	nvme_q_complete(sc, sc->sc_admin_q);
1867 	if (sc->sc_q != NULL)
1868 	        nvme_q_complete(sc, sc->sc_q[0]);
1869 
1870 	/*
1871 	 * Processing done, tell controller to issue interrupts again. There
1872 	 * is no race, as NVMe spec requires the controller to maintain state,
1873 	 * and assert the interrupt whenever there are unacknowledged
1874 	 * completion queue entries.
1875 	 */
1876 	nvme_write4(sc, NVME_INTMC, 1);
1877 }
1878 
1879 int
1880 nvme_intr_msi(void *xq)
1881 {
1882 	struct nvme_queue *q = xq;
1883 
1884 	KASSERT(q && q->q_sc && q->q_sc->sc_softih
1885 	    && q->q_sc->sc_softih[q->q_id]);
1886 
1887 	/*
1888 	 * MSI/MSI-X are edge triggered, so can handover processing to softint
1889 	 * without masking the interrupt.
1890 	 */
1891 	softint_schedule(q->q_sc->sc_softih[q->q_id]);
1892 
1893 	return 1;
1894 }
1895 
1896 void
1897 nvme_softintr_msi(void *xq)
1898 {
1899 	struct nvme_queue *q = xq;
1900 	struct nvme_softc *sc = q->q_sc;
1901 
1902 	nvme_q_complete(sc, q);
1903 }
1904 
1905 static struct nvme_dmamem *
1906 nvme_dmamem_alloc(struct nvme_softc *sc, size_t size)
1907 {
1908 	struct nvme_dmamem *ndm;
1909 	int nsegs;
1910 
1911 	ndm = kmem_zalloc(sizeof(*ndm), KM_SLEEP);
1912 	if (ndm == NULL)
1913 		return NULL;
1914 
1915 	ndm->ndm_size = size;
1916 
1917 	if (bus_dmamap_create(sc->sc_dmat, size, btoc(round_page(size)), size, 0,
1918 	    BUS_DMA_WAITOK | BUS_DMA_ALLOCNOW, &ndm->ndm_map) != 0)
1919 		goto ndmfree;
1920 
1921 	if (bus_dmamem_alloc(sc->sc_dmat, size, sc->sc_mps, 0, &ndm->ndm_seg,
1922 	    1, &nsegs, BUS_DMA_WAITOK) != 0)
1923 		goto destroy;
1924 
1925 	if (bus_dmamem_map(sc->sc_dmat, &ndm->ndm_seg, nsegs, size,
1926 	    &ndm->ndm_kva, BUS_DMA_WAITOK) != 0)
1927 		goto free;
1928 
1929 	if (bus_dmamap_load(sc->sc_dmat, ndm->ndm_map, ndm->ndm_kva, size,
1930 	    NULL, BUS_DMA_WAITOK) != 0)
1931 		goto unmap;
1932 
1933 	memset(ndm->ndm_kva, 0, size);
1934 	bus_dmamap_sync(sc->sc_dmat, ndm->ndm_map, 0, size, BUS_DMASYNC_PREREAD);
1935 
1936 	return ndm;
1937 
1938 unmap:
1939 	bus_dmamem_unmap(sc->sc_dmat, ndm->ndm_kva, size);
1940 free:
1941 	bus_dmamem_free(sc->sc_dmat, &ndm->ndm_seg, 1);
1942 destroy:
1943 	bus_dmamap_destroy(sc->sc_dmat, ndm->ndm_map);
1944 ndmfree:
1945 	kmem_free(ndm, sizeof(*ndm));
1946 	return NULL;
1947 }
1948 
1949 static void
1950 nvme_dmamem_sync(struct nvme_softc *sc, struct nvme_dmamem *mem, int ops)
1951 {
1952 	bus_dmamap_sync(sc->sc_dmat, NVME_DMA_MAP(mem),
1953 	    0, NVME_DMA_LEN(mem), ops);
1954 }
1955 
1956 void
1957 nvme_dmamem_free(struct nvme_softc *sc, struct nvme_dmamem *ndm)
1958 {
1959 	bus_dmamap_unload(sc->sc_dmat, ndm->ndm_map);
1960 	bus_dmamem_unmap(sc->sc_dmat, ndm->ndm_kva, ndm->ndm_size);
1961 	bus_dmamem_free(sc->sc_dmat, &ndm->ndm_seg, 1);
1962 	bus_dmamap_destroy(sc->sc_dmat, ndm->ndm_map);
1963 	kmem_free(ndm, sizeof(*ndm));
1964 }
1965 
1966 /*
1967  * ioctl
1968  */
1969 
1970 dev_type_open(nvmeopen);
1971 dev_type_close(nvmeclose);
1972 dev_type_ioctl(nvmeioctl);
1973 
1974 const struct cdevsw nvme_cdevsw = {
1975 	.d_open = nvmeopen,
1976 	.d_close = nvmeclose,
1977 	.d_read = noread,
1978 	.d_write = nowrite,
1979 	.d_ioctl = nvmeioctl,
1980 	.d_stop = nostop,
1981 	.d_tty = notty,
1982 	.d_poll = nopoll,
1983 	.d_mmap = nommap,
1984 	.d_kqfilter = nokqfilter,
1985 	.d_discard = nodiscard,
1986 	.d_flag = D_OTHER,
1987 };
1988 
1989 /*
1990  * Accept an open operation on the control device.
1991  */
1992 int
1993 nvmeopen(dev_t dev, int flag, int mode, struct lwp *l)
1994 {
1995 	struct nvme_softc *sc;
1996 	int unit = minor(dev) / 0x10000;
1997 	int nsid = minor(dev) & 0xffff;
1998 	int nsidx;
1999 
2000 	if ((sc = device_lookup_private(&nvme_cd, unit)) == NULL)
2001 		return ENXIO;
2002 	if ((sc->sc_flags & NVME_F_ATTACHED) == 0)
2003 		return ENXIO;
2004 
2005 	if (nsid == 0) {
2006 		/* controller */
2007 		if (ISSET(sc->sc_flags, NVME_F_OPEN))
2008 			return EBUSY;
2009 		SET(sc->sc_flags, NVME_F_OPEN);
2010 	} else {
2011 		/* namespace */
2012 		nsidx = nsid - 1;
2013 		if (nsidx >= sc->sc_nn || sc->sc_namespaces[nsidx].dev == NULL)
2014 			return ENXIO;
2015 		if (ISSET(sc->sc_namespaces[nsidx].flags, NVME_NS_F_OPEN))
2016 			return EBUSY;
2017 		SET(sc->sc_namespaces[nsidx].flags, NVME_NS_F_OPEN);
2018 	}
2019 	return 0;
2020 }
2021 
2022 /*
2023  * Accept the last close on the control device.
2024  */
2025 int
2026 nvmeclose(dev_t dev, int flag, int mode, struct lwp *l)
2027 {
2028 	struct nvme_softc *sc;
2029 	int unit = minor(dev) / 0x10000;
2030 	int nsid = minor(dev) & 0xffff;
2031 	int nsidx;
2032 
2033 	sc = device_lookup_private(&nvme_cd, unit);
2034 	if (sc == NULL)
2035 		return ENXIO;
2036 
2037 	if (nsid == 0) {
2038 		/* controller */
2039 		CLR(sc->sc_flags, NVME_F_OPEN);
2040 	} else {
2041 		/* namespace */
2042 		nsidx = nsid - 1;
2043 		if (nsidx >= sc->sc_nn)
2044 			return ENXIO;
2045 		CLR(sc->sc_namespaces[nsidx].flags, NVME_NS_F_OPEN);
2046 	}
2047 
2048 	return 0;
2049 }
2050 
2051 /*
2052  * Handle control operations.
2053  */
2054 int
2055 nvmeioctl(dev_t dev, u_long cmd, void *data, int flag, struct lwp *l)
2056 {
2057 	struct nvme_softc *sc;
2058 	int unit = minor(dev) / 0x10000;
2059 	int nsid = minor(dev) & 0xffff;
2060 	struct nvme_pt_command *pt;
2061 
2062 	sc = device_lookup_private(&nvme_cd, unit);
2063 	if (sc == NULL)
2064 		return ENXIO;
2065 
2066 	switch (cmd) {
2067 	case NVME_PASSTHROUGH_CMD:
2068 		pt = data;
2069 		return nvme_command_passthrough(sc, data,
2070 		    nsid == 0 ? pt->cmd.nsid : nsid, l, nsid == 0);
2071 	}
2072 
2073 	return ENOTTY;
2074 }
2075