xref: /freebsd/sys/x86/iommu/amd_ctx.c (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a) 
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2024 The FreeBSD Foundation
5  *
6  * This software was developed by Konstantin Belousov <kib@FreeBSD.org>
7  * under sponsorship from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/param.h>
32 #include <sys/systm.h>
33 #include <sys/malloc.h>
34 #include <sys/bus.h>
35 #include <sys/interrupt.h>
36 #include <sys/kernel.h>
37 #include <sys/ktr.h>
38 #include <sys/limits.h>
39 #include <sys/lock.h>
40 #include <sys/memdesc.h>
41 #include <sys/mutex.h>
42 #include <sys/proc.h>
43 #include <sys/rwlock.h>
44 #include <sys/rman.h>
45 #include <sys/sysctl.h>
46 #include <sys/taskqueue.h>
47 #include <sys/tree.h>
48 #include <sys/uio.h>
49 #include <sys/vmem.h>
50 #include <vm/vm.h>
51 #include <vm/vm_extern.h>
52 #include <vm/vm_kern.h>
53 #include <vm/vm_object.h>
54 #include <vm/vm_page.h>
55 #include <vm/vm_pager.h>
56 #include <vm/vm_map.h>
57 #include <contrib/dev/acpica/include/acpi.h>
58 #include <contrib/dev/acpica/include/accommon.h>
59 #include <dev/pci/pcireg.h>
60 #include <dev/pci/pcivar.h>
61 #include <machine/atomic.h>
62 #include <machine/bus.h>
63 #include <machine/md_var.h>
64 #include <machine/specialreg.h>
65 #include <x86/include/busdma_impl.h>
66 #include <dev/iommu/busdma_iommu.h>
67 #include <x86/iommu/amd_reg.h>
68 #include <x86/iommu/x86_iommu.h>
69 #include <x86/iommu/amd_iommu.h>
70 
71 static MALLOC_DEFINE(M_AMDIOMMU_CTX, "amdiommu_ctx", "AMD IOMMU Context");
72 static MALLOC_DEFINE(M_AMDIOMMU_DOMAIN, "amdiommu_dom", "AMD IOMMU Domain");
73 
74 static void amdiommu_unref_domain_locked(struct amdiommu_unit *unit,
75     struct amdiommu_domain *domain);
76 
77 static struct amdiommu_dte *
78 amdiommu_get_dtep(struct amdiommu_ctx *ctx)
79 {
80 	return (&CTX2AMD(ctx)->dev_tbl[ctx->context.rid]);
81 }
82 
83 void
84 amdiommu_domain_unload_entry(struct iommu_map_entry *entry, bool free,
85     bool cansleep)
86 {
87 	struct amdiommu_domain *domain;
88 	struct amdiommu_unit *unit;
89 
90 	domain = IODOM2DOM(entry->domain);
91 	unit = DOM2AMD(domain);
92 
93 	/*
94 	 * If "free" is false, then the IOTLB invalidation must be performed
95 	 * synchronously.  Otherwise, the caller might free the entry before
96 	 * dmar_qi_task() is finished processing it.
97 	 */
98 	if (free) {
99 		AMDIOMMU_LOCK(unit);
100 		iommu_qi_invalidate_locked(&domain->iodom, entry, true);
101 		AMDIOMMU_UNLOCK(unit);
102 	} else {
103 		iommu_qi_invalidate_sync(&domain->iodom, entry->start,
104 		    entry->end - entry->start, cansleep);
105 		iommu_domain_free_entry(entry, false);
106 	}
107 }
108 
109 static bool
110 amdiommu_domain_unload_emit_wait(struct amdiommu_domain *domain,
111     struct iommu_map_entry *entry)
112 {
113 	return (true); /* XXXKIB */
114 }
115 
116 void
117 amdiommu_domain_unload(struct iommu_domain *iodom,
118     struct iommu_map_entries_tailq *entries, bool cansleep)
119 {
120 	struct amdiommu_domain *domain;
121 	struct amdiommu_unit *unit;
122 	struct iommu_map_entry *entry, *entry1;
123 	int error __diagused;
124 
125 	domain = IODOM2DOM(iodom);
126 	unit = DOM2AMD(domain);
127 
128 	TAILQ_FOREACH_SAFE(entry, entries, dmamap_link, entry1) {
129 		KASSERT((entry->flags & IOMMU_MAP_ENTRY_MAP) != 0,
130 		    ("not mapped entry %p %p", domain, entry));
131 		error = iodom->ops->unmap(iodom, entry,
132 		    cansleep ? IOMMU_PGF_WAITOK : 0);
133 		KASSERT(error == 0, ("unmap %p error %d", domain, error));
134 	}
135 	if (TAILQ_EMPTY(entries))
136 		return;
137 
138 	AMDIOMMU_LOCK(unit);
139 	while ((entry = TAILQ_FIRST(entries)) != NULL) {
140 		TAILQ_REMOVE(entries, entry, dmamap_link);
141 		iommu_qi_invalidate_locked(&domain->iodom, entry,
142 		    amdiommu_domain_unload_emit_wait(domain, entry));
143 	}
144 	AMDIOMMU_UNLOCK(unit);
145 }
146 
147 static void
148 amdiommu_domain_destroy(struct amdiommu_domain *domain)
149 {
150 	struct iommu_domain *iodom;
151 	struct amdiommu_unit *unit;
152 
153 	iodom = DOM2IODOM(domain);
154 
155 	KASSERT(TAILQ_EMPTY(&domain->iodom.unload_entries),
156 	    ("unfinished unloads %p", domain));
157 	KASSERT(LIST_EMPTY(&iodom->contexts),
158 	    ("destroying dom %p with contexts", domain));
159 	KASSERT(domain->ctx_cnt == 0,
160 	    ("destroying dom %p with ctx_cnt %d", domain, domain->ctx_cnt));
161 	KASSERT(domain->refs == 0,
162 	    ("destroying dom %p with refs %d", domain, domain->refs));
163 
164 	if ((domain->iodom.flags & IOMMU_DOMAIN_GAS_INITED) != 0) {
165 		AMDIOMMU_DOMAIN_LOCK(domain);
166 		iommu_gas_fini_domain(iodom);
167 		AMDIOMMU_DOMAIN_UNLOCK(domain);
168 	}
169 	if ((domain->iodom.flags & IOMMU_DOMAIN_PGTBL_INITED) != 0) {
170 		if (domain->pgtbl_obj != NULL)
171 			AMDIOMMU_DOMAIN_PGLOCK(domain);
172 		amdiommu_domain_free_pgtbl(domain);
173 	}
174 	iommu_domain_fini(iodom);
175 	unit = DOM2AMD(domain);
176 	free_unr(unit->domids, domain->domain);
177 	free(domain, M_AMDIOMMU_DOMAIN);
178 }
179 
180 static iommu_gaddr_t
181 lvl2addr(int lvl)
182 {
183 	int x;
184 
185 	x = IOMMU_PAGE_SHIFT + IOMMU_NPTEPGSHIFT * lvl;
186 	/* Level 6 has only 8 bits for page table index */
187 	if (x >= NBBY * sizeof(uint64_t))
188 		return (-1ull);
189 	return (1ull < (1ull << x));
190 }
191 
192 static void
193 amdiommu_domain_init_pglvl(struct amdiommu_unit *unit,
194     struct amdiommu_domain *domain)
195 {
196 	iommu_gaddr_t end;
197 	int hats, i;
198 	uint64_t efr_hats;
199 
200 	end = DOM2IODOM(domain)->end;
201 	for (i = AMDIOMMU_PGTBL_MAXLVL; i > 1; i--) {
202 		if (lvl2addr(i) >= end && lvl2addr(i - 1) < end)
203 			break;
204 	}
205 	domain->pglvl = i;
206 
207 	efr_hats = unit->efr & AMDIOMMU_EFR_HATS_MASK;
208 	switch (efr_hats) {
209 	case AMDIOMMU_EFR_HATS_6LVL:
210 		hats = 6;
211 		break;
212 	case AMDIOMMU_EFR_HATS_5LVL:
213 		hats = 5;
214 		break;
215 	case AMDIOMMU_EFR_HATS_4LVL:
216 		hats = 4;
217 		break;
218 	default:
219 		printf("amdiommu%d: HATS %#jx (reserved) ignoring\n",
220 		    unit->iommu.unit, (uintmax_t)efr_hats);
221 		return;
222 	}
223 	if (hats >= domain->pglvl)
224 		return;
225 
226 	printf("amdiommu%d: domain %d HATS %d pglvl %d reducing to HATS\n",
227 	    unit->iommu.unit, domain->domain, hats, domain->pglvl);
228 	domain->pglvl = hats;
229 	domain->iodom.end = lvl2addr(hats);
230 }
231 
232 static struct amdiommu_domain *
233 amdiommu_domain_alloc(struct amdiommu_unit *unit, bool id_mapped)
234 {
235 	struct amdiommu_domain *domain;
236 	struct iommu_domain *iodom;
237 	int error, id;
238 
239 	id = alloc_unr(unit->domids);
240 	if (id == -1)
241 		return (NULL);
242 	domain = malloc(sizeof(*domain), M_AMDIOMMU_DOMAIN, M_WAITOK | M_ZERO);
243 	iodom = DOM2IODOM(domain);
244 	domain->domain = id;
245 	LIST_INIT(&iodom->contexts);
246 	iommu_domain_init(AMD2IOMMU(unit), iodom, &amdiommu_domain_map_ops);
247 
248 	domain->unit = unit;
249 
250 	domain->iodom.end = id_mapped ? ptoa(Maxmem) : BUS_SPACE_MAXADDR;
251 	amdiommu_domain_init_pglvl(unit, domain);
252 	iommu_gas_init_domain(DOM2IODOM(domain));
253 
254 	if (id_mapped) {
255 		domain->iodom.flags |= IOMMU_DOMAIN_IDMAP;
256 	} else {
257 		error = amdiommu_domain_alloc_pgtbl(domain);
258 		if (error != 0)
259 			goto fail;
260 		/* Disable local apic region access */
261 		error = iommu_gas_reserve_region(iodom, 0xfee00000,
262 		    0xfeefffff + 1, &iodom->msi_entry);
263 		if (error != 0)
264 			goto fail;
265 	}
266 
267 	return (domain);
268 
269 fail:
270 	amdiommu_domain_destroy(domain);
271 	return (NULL);
272 }
273 
274 static struct amdiommu_ctx *
275 amdiommu_ctx_alloc(struct amdiommu_domain *domain, uint16_t rid)
276 {
277 	struct amdiommu_ctx *ctx;
278 
279 	ctx = malloc(sizeof(*ctx), M_AMDIOMMU_CTX, M_WAITOK | M_ZERO);
280 	ctx->context.domain = DOM2IODOM(domain);
281 	ctx->context.tag = malloc(sizeof(struct bus_dma_tag_iommu),
282 	    M_AMDIOMMU_CTX, M_WAITOK | M_ZERO);
283 	ctx->context.rid = rid;
284 	ctx->context.refs = 1;
285 	return (ctx);
286 }
287 
288 static void
289 amdiommu_ctx_link(struct amdiommu_ctx *ctx)
290 {
291 	struct amdiommu_domain *domain;
292 
293 	domain = CTX2DOM(ctx);
294 	IOMMU_ASSERT_LOCKED(domain->iodom.iommu);
295 	KASSERT(domain->refs >= domain->ctx_cnt,
296 	    ("dom %p ref underflow %d %d", domain, domain->refs,
297 	    domain->ctx_cnt));
298 	domain->refs++;
299 	domain->ctx_cnt++;
300 	LIST_INSERT_HEAD(&domain->iodom.contexts, &ctx->context, link);
301 }
302 
303 static void
304 amdiommu_ctx_unlink(struct amdiommu_ctx *ctx)
305 {
306 	struct amdiommu_domain *domain;
307 
308 	domain = CTX2DOM(ctx);
309 	IOMMU_ASSERT_LOCKED(domain->iodom.iommu);
310 	KASSERT(domain->refs > 0,
311 	    ("domain %p ctx dtr refs %d", domain, domain->refs));
312 	KASSERT(domain->ctx_cnt >= domain->refs,
313 	    ("domain %p ctx dtr refs %d ctx_cnt %d", domain,
314 	    domain->refs, domain->ctx_cnt));
315 	domain->refs--;
316 	domain->ctx_cnt--;
317 	LIST_REMOVE(&ctx->context, link);
318 }
319 
320 struct amdiommu_ctx *
321 amdiommu_find_ctx_locked(struct amdiommu_unit *unit, uint16_t rid)
322 {
323 	struct amdiommu_domain *domain;
324 	struct iommu_ctx *ctx;
325 
326 	AMDIOMMU_ASSERT_LOCKED(unit);
327 
328 	LIST_FOREACH(domain, &unit->domains, link) {
329 		LIST_FOREACH(ctx, &domain->iodom.contexts, link) {
330 			if (ctx->rid == rid)
331 				return (IOCTX2CTX(ctx));
332 		}
333 	}
334 	return (NULL);
335 }
336 
337 struct amdiommu_domain *
338 amdiommu_find_domain(struct amdiommu_unit *unit, uint16_t rid)
339 {
340 	struct amdiommu_domain *domain;
341 	struct iommu_ctx *ctx;
342 
343 	AMDIOMMU_LOCK(unit);
344 	LIST_FOREACH(domain, &unit->domains, link) {
345 		LIST_FOREACH(ctx, &domain->iodom.contexts, link) {
346 			if (ctx->rid == rid)
347 				break;
348 		}
349 	}
350 	AMDIOMMU_UNLOCK(unit);
351 	return (domain);
352 }
353 
354 static void
355 amdiommu_free_ctx_locked(struct amdiommu_unit *unit, struct amdiommu_ctx *ctx)
356 {
357 	struct amdiommu_dte *dtep;
358 	struct amdiommu_domain *domain;
359 
360 	AMDIOMMU_ASSERT_LOCKED(unit);
361 	KASSERT(ctx->context.refs >= 1,
362 	    ("amdiommu %p ctx %p refs %u", unit, ctx, ctx->context.refs));
363 
364 	/*
365 	 * If our reference is not last, only the dereference should
366 	 * be performed.
367 	 */
368 	if (ctx->context.refs > 1) {
369 		ctx->context.refs--;
370 		AMDIOMMU_UNLOCK(unit);
371 		return;
372 	}
373 
374 	KASSERT((ctx->context.flags & IOMMU_CTX_DISABLED) == 0,
375 	    ("lost ref on disabled ctx %p", ctx));
376 
377 	/*
378 	 * Otherwise, the device table entry must be cleared before
379 	 * the page table is destroyed.
380 	 */
381 	dtep = amdiommu_get_dtep(ctx);
382 	dtep->v = 0;
383 	atomic_thread_fence_rel();
384 	memset(dtep, 0, sizeof(*dtep));
385 
386 	domain = CTX2DOM(ctx);
387 	amdiommu_qi_invalidate_ctx_locked_nowait(ctx);
388 	amdiommu_qi_invalidate_ir_locked_nowait(unit, ctx->context.rid);
389 	amdiommu_qi_invalidate_all_pages_locked_nowait(domain);
390 	amdiommu_qi_invalidate_wait_sync(AMD2IOMMU(CTX2AMD(ctx)));
391 
392 	if (unit->irte_enabled)
393 		amdiommu_ctx_fini_irte(ctx);
394 
395 	amdiommu_ctx_unlink(ctx);
396 	free(ctx->context.tag, M_AMDIOMMU_CTX);
397 	free(ctx, M_AMDIOMMU_CTX);
398 	amdiommu_unref_domain_locked(unit, domain);
399 }
400 
401 static void
402 amdiommu_unref_domain_locked(struct amdiommu_unit *unit,
403     struct amdiommu_domain *domain)
404 {
405 	AMDIOMMU_ASSERT_LOCKED(unit);
406 	KASSERT(domain->refs >= 1,
407 	    ("amdiommu%d domain %p refs %u", unit->iommu.unit, domain,
408 	    domain->refs));
409 	KASSERT(domain->refs > domain->ctx_cnt,
410 	    ("amdiommu%d domain %p refs %d ctx_cnt %d", unit->iommu.unit,
411 	    domain, domain->refs, domain->ctx_cnt));
412 
413 	if (domain->refs > 1) {
414 		domain->refs--;
415 		AMDIOMMU_UNLOCK(unit);
416 		return;
417 	}
418 
419 	LIST_REMOVE(domain, link);
420 	AMDIOMMU_UNLOCK(unit);
421 
422 	taskqueue_drain(unit->iommu.delayed_taskqueue,
423 	    &domain->iodom.unload_task);
424 	amdiommu_domain_destroy(domain);
425 }
426 
427 static void
428 dte_entry_init_one(struct amdiommu_dte *dtep, struct amdiommu_ctx *ctx,
429     vm_page_t pgtblr, uint8_t dte, uint32_t edte)
430 {
431 	struct amdiommu_domain *domain;
432 	struct amdiommu_unit *unit;
433 
434 	domain = CTX2DOM(ctx);
435 	unit = DOM2AMD(domain);
436 
437 	dtep->tv = 1;
438 	/* dtep->had not used for now */
439 	dtep->ir = 1;
440 	dtep->iw = 1;
441 	dtep->domainid = domain->domain;
442 	dtep->pioctl = AMDIOMMU_DTE_PIOCTL_DIS;
443 
444 	/* fill device interrupt passing hints from IVHD. */
445 	dtep->initpass = (dte & ACPI_IVHD_INIT_PASS) != 0;
446 	dtep->eintpass = (dte & ACPI_IVHD_EINT_PASS) != 0;
447 	dtep->nmipass = (dte & ACPI_IVHD_NMI_PASS) != 0;
448 	dtep->sysmgt = (dte & ACPI_IVHD_SYSTEM_MGMT) >> 4;
449 	dtep->lint0pass = (dte & ACPI_IVHD_LINT0_PASS) != 0;
450 	dtep->lint1pass = (dte & ACPI_IVHD_LINT1_PASS) != 0;
451 
452 	if (unit->irte_enabled) {
453 		dtep->iv = 1;
454 		dtep->i = 0;
455 		dtep->inttablen = ilog2(unit->irte_nentries);
456 		dtep->intrroot = pmap_kextract(unit->irte_x2apic ?
457 		    (vm_offset_t)ctx->irtx2 :
458 		    (vm_offset_t)ctx->irtb) >> 6;
459 
460 		dtep->intctl = AMDIOMMU_DTE_INTCTL_MAP;
461 	}
462 
463 	if ((DOM2IODOM(domain)->flags & IOMMU_DOMAIN_IDMAP) != 0) {
464 		dtep->pgmode = AMDIOMMU_DTE_PGMODE_1T1;
465 	} else {
466 		MPASS(domain->pglvl > 0 && domain->pglvl <=
467 		    AMDIOMMU_PGTBL_MAXLVL);
468 		dtep->pgmode = domain->pglvl;
469 		dtep->ptroot = VM_PAGE_TO_PHYS(pgtblr) >> 12;
470 	}
471 
472 	atomic_thread_fence_rel();
473 	dtep->v = 1;
474 }
475 
476 static void
477 dte_entry_init(struct amdiommu_ctx *ctx, bool move, uint8_t dte, uint32_t edte)
478 {
479 	struct amdiommu_dte *dtep;
480 	struct amdiommu_unit *unit;
481 	struct amdiommu_domain *domain;
482 	int i;
483 
484 	domain = CTX2DOM(ctx);
485 	unit = DOM2AMD(domain);
486 
487 	dtep = amdiommu_get_dtep(ctx);
488 	KASSERT(dtep->v == 0,
489 	    ("amdiommu%d initializing valid dte @%p %#jx",
490 	    CTX2AMD(ctx)->iommu.unit, dtep, (uintmax_t)(*(uint64_t *)dtep)));
491 
492 	if (iommu_is_buswide_ctx(AMD2IOMMU(unit),
493 	    PCI_RID2BUS(ctx->context.rid))) {
494 		MPASS(!move);
495 		for (i = 0; i <= PCI_BUSMAX; i++) {
496 			dte_entry_init_one(&dtep[i], ctx, domain->pgtblr,
497 			    dte, edte);
498 		}
499 	} else {
500 		dte_entry_init_one(dtep, ctx, domain->pgtblr, dte, edte);
501 	}
502 }
503 
504 struct amdiommu_ctx *
505 amdiommu_get_ctx_for_dev(struct amdiommu_unit *unit, device_t dev, uint16_t rid,
506     int dev_domain, bool id_mapped, bool rmrr_init, uint8_t dte, uint32_t edte)
507 {
508 	struct amdiommu_domain *domain, *domain1;
509 	struct amdiommu_ctx *ctx, *ctx1;
510 	int bus, slot, func;
511 
512 	if (dev != NULL) {
513 		bus = pci_get_bus(dev);
514 		slot = pci_get_slot(dev);
515 		func = pci_get_function(dev);
516 	} else {
517 		bus = PCI_RID2BUS(rid);
518 		slot = PCI_RID2SLOT(rid);
519 		func = PCI_RID2FUNC(rid);
520 	}
521 	AMDIOMMU_LOCK(unit);
522 	KASSERT(!iommu_is_buswide_ctx(AMD2IOMMU(unit), bus) ||
523 	    (slot == 0 && func == 0),
524 	    ("iommu%d pci%d:%d:%d get_ctx for buswide", AMD2IOMMU(unit)->unit,
525 	    bus, slot, func));
526 	ctx = amdiommu_find_ctx_locked(unit, rid);
527 	if (ctx == NULL) {
528 		/*
529 		 * Perform the allocations which require sleep or have
530 		 * higher chance to succeed if the sleep is allowed.
531 		 */
532 		AMDIOMMU_UNLOCK(unit);
533 		domain1 = amdiommu_domain_alloc(unit, id_mapped);
534 		if (domain1 == NULL)
535 			return (NULL);
536 		if (!id_mapped) {
537 			/*
538 			 * XXXKIB IVMD seems to be less significant
539 			 * and less used on AMD than RMRR on Intel.
540 			 * Not implemented for now.
541 			 */
542 		}
543 		ctx1 = amdiommu_ctx_alloc(domain1, rid);
544 		amdiommu_ctx_init_irte(ctx1);
545 		AMDIOMMU_LOCK(unit);
546 
547 		/*
548 		 * Recheck the contexts, other thread might have
549 		 * already allocated needed one.
550 		 */
551 		ctx = amdiommu_find_ctx_locked(unit, rid);
552 		if (ctx == NULL) {
553 			domain = domain1;
554 			ctx = ctx1;
555 			amdiommu_ctx_link(ctx);
556 			ctx->context.tag->owner = dev;
557 			iommu_device_tag_init(CTX2IOCTX(ctx), dev);
558 
559 			LIST_INSERT_HEAD(&unit->domains, domain, link);
560 			dte_entry_init(ctx, false, dte, edte);
561 			amdiommu_qi_invalidate_ctx_locked(ctx);
562 			if (dev != NULL) {
563 				device_printf(dev,
564 			    "amdiommu%d pci%d:%d:%d:%d rid %x domain %d "
565 				    "%s-mapped\n",
566 				    AMD2IOMMU(unit)->unit, unit->unit_dom,
567 				    bus, slot, func, rid, domain->domain,
568 				    id_mapped ? "id" : "re");
569 			}
570 		} else {
571 			amdiommu_domain_destroy(domain1);
572 			/* Nothing needs to be done to destroy ctx1. */
573 			free(ctx1, M_AMDIOMMU_CTX);
574 			domain = CTX2DOM(ctx);
575 			ctx->context.refs++; /* tag referenced us */
576 		}
577 	} else {
578 		domain = CTX2DOM(ctx);
579 		if (ctx->context.tag->owner == NULL)
580 			ctx->context.tag->owner = dev;
581 		ctx->context.refs++; /* tag referenced us */
582 	}
583 	AMDIOMMU_UNLOCK(unit);
584 
585 	return (ctx);
586 }
587 
588 struct iommu_ctx *
589 amdiommu_get_ctx(struct iommu_unit *iommu, device_t dev, uint16_t rid,
590     bool id_mapped, bool rmrr_init)
591 {
592 	struct amdiommu_unit *unit;
593 	struct amdiommu_ctx *ret;
594 	int error;
595 	uint32_t edte;
596 	uint16_t rid1;
597 	uint8_t dte;
598 
599 	error = amdiommu_find_unit(dev, &unit,  &rid1,  &dte, &edte,
600 	    bootverbose);
601 	if (error != 0)
602 		return (NULL);
603 	if (AMD2IOMMU(unit) != iommu)	/* XXX complain loudly */
604 		return (NULL);
605 	ret = amdiommu_get_ctx_for_dev(unit, dev, rid1, pci_get_domain(dev),
606 	    id_mapped, rmrr_init, dte, edte);
607 	return (CTX2IOCTX(ret));
608 }
609 
610 void
611 amdiommu_free_ctx_locked_method(struct iommu_unit *iommu,
612     struct iommu_ctx *context)
613 {
614 	struct amdiommu_unit *unit;
615 	struct amdiommu_ctx *ctx;
616 
617 	unit = IOMMU2AMD(iommu);
618 	ctx = IOCTX2CTX(context);
619 	amdiommu_free_ctx_locked(unit, ctx);
620 }
621