Index: sys/arm/arm/mem.c
===================================================================
--- sys/arm/arm/mem.c	(revision 269763)
+++ sys/arm/arm/mem.c	(working copy)
@@ -68,9 +68,21 @@
 /*
  * Used in /dev/mem drivers and elsewhere
  */
+static void arm_mrinit(struct mem_range_softc *);
+static int arm_mrset(struct mem_range_softc *, struct mem_range_desc *, int *);
+
 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
 
-struct mem_range_softc mem_range_softc;
+static struct mem_range_ops arm_mem_range_ops = {
+	arm_mrinit,
+	arm_mrset,
+	NULL,
+	NULL
+};
+struct mem_range_softc mem_range_softc = {
+	&arm_mem_range_ops,
+	0, 0, NULL
+}; 
 
 /* ARGSUSED */
 int
@@ -152,12 +164,132 @@
 
 int
 memmmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
-    int prot __unused, vm_memattr_t *memattr __unused)
+    int prot __unused, vm_memattr_t *memattr)
 {
-	if (dev2unit(dev) == CDEV_MINOR_MEM)
+	int i;
+
+	if (dev2unit(dev) == CDEV_MINOR_KMEM)
+        	*paddr = vtophys(offset);
+	else if (dev2unit(dev) == CDEV_MINOR_MEM) {
 		*paddr = offset;
-	else if (dev2unit(dev) == CDEV_MINOR_KMEM)
-        	*paddr = vtophys(offset);
+
+		for (i = 0; i < mem_range_softc.mr_ndesc; i++) {
+			if ((mem_range_softc.mr_desc[i].mr_flags &
+			     MDF_ACTIVE) != 0 &&
+			    offset >= mem_range_softc.mr_desc[i].mr_base &&
+			    offset < mem_range_softc.mr_desc[i].mr_base +
+			    mem_range_softc.mr_desc[i].mr_len &&
+			    (mem_range_softc.mr_desc[i].mr_flags &
+			     MDF_ATTRMASK) == MDF_UNCACHEABLE) {
+				*memattr = VM_MEMATTR_UNCACHEABLE;
+				break;
+			}
+		}
+	}
 	/* else panic! */
 	return (0);
 }
+
+static void
+arm_mrinit(struct mem_range_softc *sc)
+{
+	sc->mr_cap = 0;
+	sc->mr_ndesc = 8; /* XXX: Should be dynamically expandable */
+	sc->mr_desc = malloc(sc->mr_ndesc * sizeof(struct mem_range_desc),
+	    M_MEMDESC, M_NOWAIT | M_ZERO);
+	if (sc->mr_desc == NULL)
+		panic("%s: malloc returns NULL", __func__);
+}
+
+static int
+arm_mrset(struct mem_range_softc *sc, struct mem_range_desc *desc, int *arg)
+{
+	int i;
+
+	switch(*arg) {
+	case MEMRANGE_SET_UPDATE:
+		for (i = 0; i < sc->mr_ndesc; i++) {
+			if (!sc->mr_desc[i].mr_len) {
+				sc->mr_desc[i] = *desc;
+				sc->mr_desc[i].mr_flags |= MDF_ACTIVE;
+				return (0);
+			}
+			if (sc->mr_desc[i].mr_base == desc->mr_base &&
+			    sc->mr_desc[i].mr_len == desc->mr_len)
+				return (EEXIST);
+		}
+		return (ENOSPC);
+	case MEMRANGE_SET_REMOVE:
+		for (i = 0; i < sc->mr_ndesc; i++)
+			if (sc->mr_desc[i].mr_base == desc->mr_base &&
+			    sc->mr_desc[i].mr_len == desc->mr_len) {
+				bzero(&sc->mr_desc[i], sizeof(sc->mr_desc[i]));
+				return (0);
+			}
+		return (ENOENT);
+	default:
+		return (EOPNOTSUPP);
+	}
+
+	return (0);
+}
+
+/*
+ * Operations for changing memory attributes.
+ *
+ * This is basically just an ioctl shim for mem_range_attr_get
+ * and mem_range_attr_set.
+ */
+/* ARGSUSED */
+int 
+memioctl(struct cdev *dev __unused, u_long cmd, caddr_t data, int flags,
+	 struct thread *td)
+{
+	int nd, error = 0;
+	struct mem_range_op *mo = (struct mem_range_op *)data;
+	struct mem_range_desc *md;
+	
+	/* is this for us? */
+	if ((cmd != MEMRANGE_GET) &&
+	    (cmd != MEMRANGE_SET))
+		return (ENOTTY);
+
+	/* any chance we can handle this? */
+	if (mem_range_softc.mr_op == NULL)
+		return (EOPNOTSUPP);
+
+	/* do we have any descriptors? */
+	if (mem_range_softc.mr_ndesc == 0)
+		return (ENXIO);
+
+	switch (cmd) {
+	case MEMRANGE_GET:
+		nd = imin(mo->mo_arg[0], mem_range_softc.mr_ndesc);
+		if (nd > 0) {
+			md = (struct mem_range_desc *)
+				malloc(nd * sizeof(struct mem_range_desc),
+				       M_MEMDESC, M_WAITOK);
+			error = mem_range_attr_get(md, &nd);
+			if (!error)
+				error = copyout(md, mo->mo_desc, 
+					nd * sizeof(struct mem_range_desc));
+			free(md, M_MEMDESC);
+		}
+		else
+			nd = mem_range_softc.mr_ndesc;
+		mo->mo_arg[0] = nd;
+		break;
+		
+	case MEMRANGE_SET:
+		md = (struct mem_range_desc *)malloc(sizeof(struct mem_range_desc),
+						    M_MEMDESC, M_WAITOK);
+		error = copyin(mo->mo_desc, md, sizeof(struct mem_range_desc));
+		/* clamp description string */
+		md->mr_owner[sizeof(md->mr_owner) - 1] = 0;
+		if (error == 0)
+			error = mem_range_attr_set(md, &mo->mo_arg[0]);
+		free(md, M_MEMDESC);
+		break;
+	}
+	return (error);
+}
Index: sys/arm/include/memdev.h
===================================================================
--- sys/arm/include/memdev.h	(revision 269763)
+++ sys/arm/include/memdev.h	(working copy)
@@ -34,7 +34,7 @@
 
 d_open_t	memopen;
 d_read_t	memrw;
+d_ioctl_t	memioctl;
 d_mmap_t	memmmap;
-#define		memioctl	(d_ioctl_t *)NULL
 
 #endif /* _MACHINE_MEMDEV_H_ */