Index: sys/arm64/iommu/iommu.c
===================================================================
--- sys/arm64/iommu/iommu.c
+++ sys/arm64/iommu/iommu.c
@@ -410,16 +410,10 @@
 static void
 iommu_domain_free_entry(struct iommu_map_entry *entry, bool free)
 {
-	struct iommu_domain *iodom;
-
-	iodom = entry->domain;
-
-	IOMMU_DOMAIN_LOCK(iodom);
-	iommu_gas_free_space(iodom, entry);
-	IOMMU_DOMAIN_UNLOCK(iodom);
+	iommu_gas_free_space(entry);
 
 	if (free)
-		iommu_gas_free_entry(iodom, entry);
+		iommu_gas_free_entry(entry);
 	else
 		entry->flags = 0;
 }
Index: sys/dev/iommu/busdma_iommu.c
===================================================================
--- sys/dev/iommu/busdma_iommu.c
+++ sys/dev/iommu/busdma_iommu.c
@@ -1040,7 +1040,7 @@
 	ma = malloc(sizeof(vm_page_t) * atop(length), M_TEMP, waitok ?
 	    M_WAITOK : M_NOWAIT);
 	if (ma == NULL) {
-		iommu_gas_free_entry(domain, entry);
+		iommu_gas_free_entry(entry);
 		return (ENOMEM);
 	}
 	for (i = 0; i < atop(length); i++) {
@@ -1055,7 +1055,7 @@
 		TAILQ_INSERT_TAIL(&map->map_entries, entry, dmamap_link);
 		IOMMU_DMAMAP_UNLOCK(map);
 	} else {
-		iommu_gas_free_entry(domain, entry);
+		iommu_gas_free_entry(entry);
 	}
 	for (i = 0; i < atop(length); i++)
 		vm_page_putfake(ma[i]);
Index: sys/dev/iommu/iommu.h
===================================================================
--- sys/dev/iommu/iommu.h
+++ sys/dev/iommu/iommu.h
@@ -169,15 +169,12 @@
 void iommu_gas_fini_domain(struct iommu_domain *domain);
 struct iommu_map_entry *iommu_gas_alloc_entry(struct iommu_domain *domain,
     u_int flags);
-void iommu_gas_free_entry(struct iommu_domain *domain,
-    struct iommu_map_entry *entry);
-void iommu_gas_free_space(struct iommu_domain *domain,
-    struct iommu_map_entry *entry);
+void iommu_gas_free_entry(struct iommu_map_entry *entry);
+void iommu_gas_free_space(struct iommu_map_entry *entry);
 int iommu_gas_map(struct iommu_domain *domain,
     const struct bus_dma_tag_common *common, iommu_gaddr_t size, int offset,
     u_int eflags, u_int flags, vm_page_t *ma, struct iommu_map_entry **res);
-void iommu_gas_free_region(struct iommu_domain *domain,
-    struct iommu_map_entry *entry);
+void iommu_gas_free_region(struct iommu_map_entry *entry);
 int iommu_gas_map_region(struct iommu_domain *domain,
     struct iommu_map_entry *entry, u_int eflags, u_int flags, vm_page_t *ma);
 int iommu_gas_reserve_region(struct iommu_domain *domain, iommu_gaddr_t start,
Index: sys/dev/iommu/iommu_gas.c
===================================================================
--- sys/dev/iommu/iommu_gas.c
+++ sys/dev/iommu/iommu_gas.c
@@ -107,12 +107,11 @@
 }
 
 void
-iommu_gas_free_entry(struct iommu_domain *domain, struct iommu_map_entry *entry)
+iommu_gas_free_entry(struct iommu_map_entry *entry)
 {
+	struct iommu_domain *domain;
 
-	KASSERT(domain == entry->domain,
-	    ("mismatched free domain %p entry %p entry->domain %p", domain,
-	    entry, entry->domain));
+	domain = entry->domain;
 	if (domain != NULL)
 		atomic_subtract_int(&domain->entries_cnt, 1);
 	uma_zfree(iommu_map_entry_zone, entry);
@@ -261,7 +260,7 @@
 	    (IOMMU_MAP_ENTRY_PLACE | IOMMU_MAP_ENTRY_UNMAPPED),
 	    ("start entry flags %p", domain));
 	RB_REMOVE(iommu_gas_entries_tree, &domain->rb_root, entry);
-	iommu_gas_free_entry(domain, entry);
+	iommu_gas_free_entry(entry);
 
 	entry = RB_MAX(iommu_gas_entries_tree, &domain->rb_root);
 	KASSERT(entry->start == domain->end, ("end entry start %p", domain));
@@ -270,7 +269,7 @@
 	    (IOMMU_MAP_ENTRY_PLACE | IOMMU_MAP_ENTRY_UNMAPPED),
 	    ("end entry flags %p", domain));
 	RB_REMOVE(iommu_gas_entries_tree, &domain->rb_root, entry);
-	iommu_gas_free_entry(domain, entry);
+	iommu_gas_free_entry(entry);
 
 	RB_FOREACH_SAFE(entry, iommu_gas_entries_tree, &domain->rb_root,
 	    entry1) {
@@ -278,7 +277,7 @@
 		    ("non-RMRR entry left %p", domain));
 		RB_REMOVE(iommu_gas_entries_tree, &domain->rb_root,
 		    entry);
-		iommu_gas_free_entry(domain, entry);
+		iommu_gas_free_entry(entry);
 	}
 }
 
@@ -558,32 +557,37 @@
 }
 
 void
-iommu_gas_free_space(struct iommu_domain *domain, struct iommu_map_entry *entry)
+iommu_gas_free_space(struct iommu_map_entry *entry)
 {
+	struct iommu_domain *domain;
 
-	IOMMU_DOMAIN_ASSERT_LOCKED(domain);
+	domain = entry->domain;
 	KASSERT((entry->flags & (IOMMU_MAP_ENTRY_PLACE | IOMMU_MAP_ENTRY_RMRR |
 	    IOMMU_MAP_ENTRY_MAP)) == IOMMU_MAP_ENTRY_MAP,
 	    ("permanent entry %p %p", domain, entry));
 
+	IOMMU_DOMAIN_LOCK(domain);
 	iommu_gas_rb_remove(domain, entry);
 	entry->flags &= ~IOMMU_MAP_ENTRY_MAP;
 #ifdef INVARIANTS
 	if (iommu_check_free)
 		iommu_gas_check_free(domain);
 #endif
+	IOMMU_DOMAIN_UNLOCK(domain);
 }
 
 void
-iommu_gas_free_region(struct iommu_domain *domain, struct iommu_map_entry *entry)
+iommu_gas_free_region(struct iommu_map_entry *entry)
 {
+	struct iommu_domain *domain;
 	struct iommu_map_entry *next, *prev;
 
-	IOMMU_DOMAIN_ASSERT_LOCKED(domain);
+	domain = entry->domain;
 	KASSERT((entry->flags & (IOMMU_MAP_ENTRY_PLACE | IOMMU_MAP_ENTRY_RMRR |
 	    IOMMU_MAP_ENTRY_MAP)) == IOMMU_MAP_ENTRY_RMRR,
 	    ("non-RMRR entry %p %p", domain, entry));
 
+	IOMMU_DOMAIN_LOCK(domain);
 	prev = RB_PREV(iommu_gas_entries_tree, &domain->rb_root, entry);
 	next = RB_NEXT(iommu_gas_entries_tree, &domain->rb_root, entry);
 	iommu_gas_rb_remove(domain, entry);
@@ -593,6 +597,7 @@
 		iommu_gas_rb_insert(domain, domain->first_place);
 	if (next == NULL)
 		iommu_gas_rb_insert(domain, domain->last_place);
+	IOMMU_DOMAIN_UNLOCK(domain);
 }
 
 int
@@ -621,7 +626,7 @@
 	error = iommu_gas_find_space(&a);
 	if (error == ENOMEM) {
 		IOMMU_DOMAIN_UNLOCK(domain);
-		iommu_gas_free_entry(domain, entry);
+		iommu_gas_free_entry(entry);
 		return (error);
 	}
 #ifdef INVARIANTS
@@ -716,7 +721,7 @@
 	error = iommu_gas_reserve_region_locked(domain, start, end, entry);
 	IOMMU_DOMAIN_UNLOCK(domain);
 	if (error != 0)
-		iommu_gas_free_entry(domain, entry);
+		iommu_gas_free_entry(entry);
 	else if (entry0 != NULL)
 		*entry0 = entry;
 	return (error);
@@ -770,7 +775,7 @@
 	}
 	/* Release a preallocated entry if it was not used. */
 	if (entry != NULL)
-		iommu_gas_free_entry(domain, entry);
+		iommu_gas_free_entry(entry);
 	return (error);
 }
 
@@ -788,11 +793,9 @@
 	domain->ops->unmap(domain, entry->start, entry->end -
 	    entry->start, IOMMU_PGF_WAITOK);
 
-	IOMMU_DOMAIN_LOCK(domain);
-	iommu_gas_free_space(domain, entry);
-	IOMMU_DOMAIN_UNLOCK(domain);
+	iommu_gas_free_space(entry);
 
-	iommu_gas_free_entry(domain, entry);
+	iommu_gas_free_entry(entry);
 
 	domain->msi_entry = NULL;
 	domain->msi_base = 0;
@@ -832,7 +835,7 @@
 				 * We lost the race and already have an
 				 * MSI page allocated. Free the unneeded entry.
 				 */
-				iommu_gas_free_entry(domain, entry);
+				iommu_gas_free_entry(entry);
 			}
 		} else if (domain->msi_entry != NULL) {
 			/*
Index: sys/x86/iommu/intel_ctx.c
===================================================================
--- sys/x86/iommu/intel_ctx.c
+++ sys/x86/iommu/intel_ctx.c
@@ -307,7 +307,7 @@
 				error = error1;
 			}
 			TAILQ_REMOVE(&rmrr_entries, entry, dmamap_link);
-			iommu_gas_free_entry(DOM2IODOM(domain), entry);
+			iommu_gas_free_entry(entry);
 		}
 		for (i = 0; i < size; i++)
 			vm_page_putfake(ma[i]);
@@ -852,17 +852,12 @@
 void
 dmar_domain_free_entry(struct iommu_map_entry *entry, bool free)
 {
-	struct iommu_domain *domain;
-
-	domain = entry->domain;
-	IOMMU_DOMAIN_LOCK(domain);
 	if ((entry->flags & IOMMU_MAP_ENTRY_RMRR) != 0)
-		iommu_gas_free_region(domain, entry);
+		iommu_gas_free_region(entry);
 	else
-		iommu_gas_free_space(domain, entry);
-	IOMMU_DOMAIN_UNLOCK(domain);
+		iommu_gas_free_space(entry);
 	if (free)
-		iommu_gas_free_entry(domain, entry);
+		iommu_gas_free_entry(entry);
 	else
 		entry->flags = 0;
 }
Index: sys/x86/iommu/intel_qi.c
===================================================================
--- sys/x86/iommu/intel_qi.c
+++ sys/x86/iommu/intel_qi.c
@@ -415,7 +415,6 @@
 dmar_qi_task(void *arg, int pending __unused)
 {
 	struct dmar_unit *unit;
-	struct iommu_domain *domain;
 	struct iommu_map_entry *entry, *head;
 	uint32_t ics;
 
@@ -440,14 +439,11 @@
 		if (!dmar_qi_seq_processed(unit, &entry->gseq))
 			break;
 		unit->tlb_flush_head = entry;
-		iommu_gas_free_entry(head->domain, head);
-		domain = entry->domain;
-		IOMMU_DOMAIN_LOCK(domain);
+		iommu_gas_free_entry(head);
 		if ((entry->flags & IOMMU_MAP_ENTRY_RMRR) != 0)
-			iommu_gas_free_region(domain, entry);
+			iommu_gas_free_region(entry);
 		else
-			iommu_gas_free_space(domain, entry);
-		IOMMU_DOMAIN_UNLOCK(domain);
+			iommu_gas_free_space(entry);
 	}
 	if (unit->inv_seq_waiters > 0) {
 		/*