Index: share/man/man9/zone.9
===================================================================
--- share/man/man9/zone.9
+++ share/man/man9/zone.9
@@ -340,6 +340,10 @@
 See
 .Xr numa 4
 for more details.
+.It Dv UMA_ZONE_CONTIG
+Items in this zone must be contiguous in physical address space.  Items will
+follow normal alignment constraints and may span page boundaries, but only
+between pages with contiguous physical addresses.
 .El
 .Pp
 Zones can be destroyed using
@@ -466,11 +470,11 @@
 functions allow a zone's default slab allocation and free functions to be
 overridden.
 This is useful if the zone's items have special memory allocation constraints.
-For example, if multi-page objects are required to be physically contiguous,
-an
+For example, if memory with a memory attribute other than
+.Dv VM_MEMATTR_DEFAULT
+must be used, then an
 .Fa allocf
-function which requests contiguous memory from the kernel's page allocator
-may be used.
+function which yields such memory should be set.
 .Pp
 The
 .Fn uma_zone_set_max
Index: sys/vm/uma.h
===================================================================
--- sys/vm/uma.h
+++ sys/vm/uma.h
@@ -235,6 +235,7 @@
  * overlap when adding new features.
  */
 #define UMA_ZONE_ZINIT		0x0002	/* Initialize with zeros */
+#define UMA_ZONE_CONTIG		0x0004	/* Objects are physically contiguous */
 #define UMA_ZONE_NOTOUCH	0x0008	/* UMA may not access the memory */
 #define UMA_ZONE_MALLOC		0x0010	/* For use by malloc(9) only! */
 #define UMA_ZONE_NOFREE		0x0020	/* Do not free slabs of this type! */
@@ -606,8 +607,7 @@
 #define UMA_SLAB_BOOT	0x01		/* Slab alloced from boot pages */
 #define UMA_SLAB_KERNEL	0x04		/* Slab alloced from kmem */
 #define UMA_SLAB_PRIV	0x08		/* Slab alloced from priv allocator */
-#define UMA_SLAB_OFFP	0x10		/* Slab is managed separately  */
-/* 0x02, 0x40, and 0x80 are available */
+/* 0x02, 0x10, 0x40, and 0x80 are available */
 
 /*
  * Used to pre-fill a zone with some number of items
Index: sys/vm/uma_core.c
===================================================================
--- sys/vm/uma_core.c
+++ sys/vm/uma_core.c
@@ -263,6 +263,7 @@
 static void *page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
 static void *pcpu_page_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
 static void *startup_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
+static void *contig_alloc(uma_zone_t, vm_size_t, int, uint8_t *, int);
 static void page_free(void *, vm_size_t, uint8_t);
 static void pcpu_page_free(void *, vm_size_t, uint8_t);
 static uma_slab_t keg_alloc_slab(uma_keg_t, uma_zone_t, int, int, int);
@@ -1607,6 +1608,19 @@
 	return ((void *)retkva);
 }
 
+/*
+ * Allocate physically contiguous pages.
+ */
+static void *
+contig_alloc(uma_zone_t zone, vm_size_t bytes, int domain, uint8_t *pflag,
+    int wait)
+{
+
+	*pflag = UMA_SLAB_KERNEL;
+	return ((void *)kmem_alloc_contig_domainset(DOMAINSET_FIXED(domain),
+	    bytes, wait, 0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT));
+}
+
 /*
  * Frees a number of pages to the system
  *
@@ -1627,8 +1641,8 @@
 		return;
 	}
 
-	if ((flags & UMA_SLAB_KERNEL) == 0)
-		panic("UMA: page_free used with invalid flags %x", flags);
+	KASSERT((flags & UMA_SLAB_KERNEL) != 0,
+	    ("UMA: page_free used with invalid flags %x", flags));
 
 	kmem_free((vm_offset_t)mem, size);
 }
@@ -1952,6 +1966,9 @@
 	if (arg->flags & UMA_ZONE_MALLOC)
 		keg->uk_flags |= UMA_ZFLAG_VTOSLAB;
 
+	KASSERT((keg->uk_flags & UMA_ZONE_PCPU) == 0 || booted >= BOOT_KVA,
+	    ("Early boot PCPU zones not implemented, keg %s flags 0x%#b",
+	     keg->uk_name, keg->uk_flags, PRINT_UMA_ZFLAGS));
 #ifndef SMP
 	keg->uk_flags &= ~UMA_ZONE_PCPU;
 #endif
@@ -1986,6 +2003,8 @@
 		keg->uk_allocf = startup_alloc;
 	else if (keg->uk_flags & UMA_ZONE_PCPU)
 		keg->uk_allocf = pcpu_page_alloc;
+	else if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 && keg->uk_ppera > 1)
+		keg->uk_allocf = contig_alloc;
 	else
 		keg->uk_allocf = page_alloc;
 #ifdef UMA_MD_SMALL_ALLOC
@@ -2047,8 +2066,13 @@
 	if ((zone->uz_flags & UMA_ZFLAG_CACHE) != 0)
 		return;
 	KEG_GET(zone, keg);
-	if (keg->uk_allocf == startup_alloc)
-		keg->uk_allocf = page_alloc;
+	if (keg->uk_allocf == startup_alloc) {
+		if ((keg->uk_flags & UMA_ZONE_CONTIG) != 0 &&
+		    keg->uk_ppera > 1)
+			keg->uk_allocf = contig_alloc;
+		else
+			keg->uk_allocf = page_alloc;
+	}
 }
 
 static void
Index: sys/vm/uma_int.h
===================================================================
--- sys/vm/uma_int.h
+++ sys/vm/uma_int.h
@@ -199,6 +199,7 @@
     "\6NOFREE"				\
     "\5MALLOC"				\
     "\4NOTOUCH"				\
+    "\3CONTIG"				\
     "\2ZINIT"
 
 /*