Break out the MI part of the /dev/[k]mem and /dev/io drivers into

their own directory and module, leaving the MD parts in the MD
area (the MD parts _are_ part of the modules). /dev/mem and /dev/io
are now loadable modules, thus taking us one step further towards
a kernel created entirely out of modules. Of course, there is nothing
preventing the kernel from having these statically compiled.

37 files changed, 833 insertions, 692 deletions

diff --git a/sys/alpha/alpha/mem.c b/sys/alpha/alpha/mem.c
index a64ea2a..fdc59ca 100644
--- a/sys/alpha/alpha/mem.c
+++ b/sys/alpha/alpha/mem.c
@@ -59,84 +59,18 @@ __FBSDID("$FreeBSD$");
 #include <sys/uio.h>
 
 #include <machine/md_var.h>
-#ifdef PERFMON
-#include <machine/perfmon.h>
-#endif
 
 #include <vm/vm.h>
 #include <vm/pmap.h>
 #include <vm/vm_extern.h>
 
-static struct cdev *memdev, *kmemdev;
-#ifdef PERFMON
-static struct cdev *perfdev;
-#endif /* PERFMON */
-
-static	d_open_t	mmopen;
-static	d_close_t	mmclose;
-static	d_read_t	mmrw;
-static	d_ioctl_t	mmioctl;
-static	d_mmap_t	memmmap;
-
-#define CDEV_MAJOR 2
-static struct cdevsw mem_cdevsw = {
-	.d_version =	D_VERSION,
-	.d_open =	mmopen,
-	.d_close =	mmclose,
-	.d_read =	mmrw,
-	.d_write =	mmrw,
-	.d_ioctl =	mmioctl,
-	.d_mmap =	memmmap,
-	.d_name =	"mem",
-	.d_maj =	CDEV_MAJOR,
-	.d_flags =	D_MEM | D_NEEDGIANT,
-};
+#include <machine/memdev.h>
 
 struct mem_range_softc mem_range_softc;
 
-static int
-mmclose(struct cdev *dev, int flags, int fmt, struct thread *td)
-{
-	switch (minor(dev)) {
-#ifdef PERFMON
-	case 32:
-		return perfmon_close(dev, flags, fmt, td);
-#endif
-	default:
-		break;
-	}
-	return (0);
-}
-
-static int
-mmopen(struct cdev *dev, int flags, int fmt, struct thread *td)
-{
-	int error;
-
-	switch (minor(dev)) {
-	case 0:
-	case 1:
-		if (flags & FWRITE) {
-			error = securelevel_gt(td->td_ucred, 0);
-			if (error)
-				return (error);
-		}
-		break;
-	case 32:
-#ifdef PERFMON
-		return perfmon_open(dev, flags, fmt, td);
-#else
-		return ENODEV;
-#endif
-	default:
-		break;
-	}
-	return (0);
-}
-
-/*ARGSUSED*/
-static int
-mmrw(struct cdev *dev, struct uio *uio, int flags)
+/* ARGSUSED */
+int
+memrw(struct cdev *dev, struct uio *uio, int flags)
 {
 	vm_offset_t o, v;
 	int c = 0;
@@ -152,13 +86,10 @@ mmrw(struct cdev *dev, struct uio *uio, int flags)
 			uio->uio_iov++;
 			uio->uio_iovcnt--;
 			if (uio->uio_iovcnt < 0)
-				panic("mmrw");
+				panic("memrw");
 			continue;
 		}
-		switch (minor(dev)) {
-
-/* minor device 0 is physical memory */
-		case 0:
+		if (minor(dev) == CDEV_MINOR_MEM) {
 			v = uio->uio_offset;
 kmemphys:
 			/* Allow reads only in RAM. */
@@ -174,9 +105,8 @@ kmemphys:
 			error =
 			    uiomove((caddr_t)ALPHA_PHYS_TO_K0SEG(v), c, uio);
 			continue;
-
-/* minor device 1 is kernel memory */
-		case 1:
+		}
+		else if (minor(dev) == CDEV_MINOR_KMEM) {
 			v = uio->uio_offset;
 
 			if (v >= ALPHA_K0SEG_BASE && v <= ALPHA_K0SEG_END) {
@@ -186,8 +116,9 @@ kmemphys:
 
 			c = min(iov->iov_len, MAXPHYS);
 			/*
-			 * Make sure that all of the pages are currently resident so
-			 * that we don't create any zero-fill pages.
+			 * Make sure that all of the pages are currently
+			 * resident so that we don't create any zero-fill
+			 * pages.
 			 */
 			addr = trunc_page(v);
 			eaddr = round_page(v + c);
@@ -203,22 +134,16 @@ kmemphys:
 			error = uiomove((caddr_t)v, c, uio);
 			continue;
 		}
-
-		if (error)
-			break;
-		iov->iov_base = (char *)iov->iov_base + c;
-		iov->iov_len -= c;
-		uio->uio_offset += c;
-		uio->uio_resid -= c;
+		/* else panic! */
 	}
 	return (error);
 }
 
-/*******************************************************\
-* allow user processes to MMAP some memory sections	*
-* instead of going through read/write			*
-\*******************************************************/
-static int
+/*
+ * allow user processes to MMAP some memory sections
+ * instead of going through read/write
+ */
+int
 memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
 {
 	/*
@@ -227,7 +152,7 @@ memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
 	 * could be transient and hence incorrect or invalid at
 	 * a later time.
 	 */
-	if (minor(dev) != 0)
+	if (minor(dev) != CDEV_MINOR_MEM)
 		return (-1);
 
 	/*
@@ -239,59 +164,7 @@ memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
 	return (0);
 }
 
-static int
-mmioctl(struct cdev *dev, u_long cmd, caddr_t cmdarg, int flags, struct thread *td)
-{
-	switch(minor(dev)) {
-#ifdef PERFMON
-	case 32:
-		return perfmon_ioctl(dev, cmd, cmdarg, flags, td);
-#endif
-	default:
-		return ENODEV;
-	}
-
-	return (0);
-}
-
-static int
-mem_modevent(module_t mod, int type, void *data)
+void
+dev_mem_md_init(void)
 {
-	switch(type) {
-	case MOD_LOAD:
-		if (bootverbose)
-			printf("mem: <memory & I/O>\n");
-/* XXX - ??? */
-#if 0
-		/* Initialise memory range handling */
-		if (mem_range_softc.mr_op != NULL)
-			mem_range_softc.mr_op->init(&mem_range_softc);
-#endif
-
-		memdev = make_dev(&mem_cdevsw, 0, UID_ROOT, GID_KMEM,
-			0640, "mem");
-		kmemdev = make_dev(&mem_cdevsw, 1, UID_ROOT, GID_KMEM,
-			0640, "kmem");
-#ifdef PERFMON
-		perfdev = make_dev(&mem_cdevsw, 32, UID_ROOT, GID_KMEM,
-			0640, "perfmon");
-#endif /* PERFMON */
-		return 0;
-
-	case MOD_UNLOAD:
-		destroy_dev(memdev);
-		destroy_dev(kmemdev);
-#ifdef PERFMON
-		destroy_dev(perfdev);
-#endif /* PERFMON */
-		return 0;
-
-	case MOD_SHUTDOWN:
-		return 0;
-
-	default:
-		return EOPNOTSUPP;
-	}
 }
-
-DEV_MODULE(mem, mem_modevent, NULL);
diff --git a/sys/alpha/conf/GENERIC b/sys/alpha/conf/GENERIC
index b472cf5..08edc0f 100644
--- a/sys/alpha/conf/GENERIC
+++ b/sys/alpha/conf/GENERIC
@@ -171,8 +171,10 @@ device		wb		# Winbond W89C840F
 device		xl		# 3Com 3c90x (``Boomerang'', ``Cyclone'')
 
 # Pseudo devices.
-device		random		# Entropy device
 device		loop		# Network loopback
+device		mem		# Memory and kernel memory devices
+device		null		# Null and zero devices
+device		random		# Entropy device
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
 device		ppp		# Kernel PPP
diff --git a/sys/alpha/include/memdev.h b/sys/alpha/include/memdev.h
new file mode 100644
index 0000000..e2ec491
--- /dev/null
+++ b/sys/alpha/include/memdev.h
@@ -0,0 +1,38 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#define CDEV_MAJOR	2
+#define	CDEV_MINOR_MEM	0
+#define	CDEV_MINOR_KMEM	1
+
+d_open_t	memopen;
+d_read_t	memrw;
+#define		memioctl	(d_ioctl_t *)NULL;
+d_mmap_t	memmmap;
+
+void		dev_mem_md_init(void);
diff --git a/sys/amd64/amd64/io.c b/sys/amd64/amd64/io.c
new file mode 100644
index 0000000..1aaf2ef
--- /dev/null
+++ b/sys/amd64/amd64/io.c
@@ -0,0 +1,77 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/conf.h>
+#include <sys/fcntl.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/signalvar.h>
+#include <sys/systm.h>
+
+#include <machine/db_machdep.h>
+#include <machine/frame.h>
+#include <machine/psl.h>
+#include <machine/specialreg.h>
+
+#include <vm/vm.h>
+#include <vm/pmap.h>
+
+#include <machine/iodev.h>
+
+/* ARGSUSED */
+int
+ioopen(struct cdev *dev __unused, int flags __unused, int fmt __unused,
+    struct thread *td)
+{
+	int error;
+
+	error = suser(td);
+	if (error != 0)
+		return (error);
+	error = securelevel_gt(td->td_ucred, 0);
+	if (error != 0)
+		return (error);
+
+	td->td_frame->tf_rflags |= PSL_IOPL;
+
+	return (0);
+}
+
+/* ARGSUSED */
+int
+ioclose(struct cdev *dev __unused, int flags __unused, int fmt __unused,
+    struct thread *td)
+{
+	td->td_frame->tf_rflags &= ~PSL_IOPL;
+
+	return (0);
+}
diff --git a/sys/amd64/amd64/mem.c b/sys/amd64/amd64/mem.c
index 739ae6d..2d0506e 100644
--- a/sys/amd64/amd64/mem.c
+++ b/sys/amd64/amd64/mem.c
@@ -47,7 +47,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/conf.h>
 #include <sys/fcntl.h>
 #include <sys/ioccom.h>
-#include <sys/kernel.h>
 #include <sys/lock.h>
 #include <sys/malloc.h>
 #include <sys/memrange.h>
@@ -58,82 +57,19 @@ __FBSDID("$FreeBSD$");
 #include <sys/systm.h>
 #include <sys/uio.h>
 
-#include <machine/db_machdep.h>
-#include <machine/frame.h>
-#include <machine/psl.h>
 #include <machine/specialreg.h>
-#include <machine/vmparam.h>
 
 #include <vm/vm.h>
 #include <vm/pmap.h>
 #include <vm/vm_extern.h>
 
-static struct cdev *memdev, *kmemdev, *iodev;
-
-static	d_open_t	mmopen;
-static	d_close_t	mmclose;
-static	d_read_t	mmrw;
-static	d_ioctl_t	mmioctl;
-static	d_mmap_t	memmmap;
-
-#define CDEV_MAJOR 2
-static struct cdevsw mem_cdevsw = {
-	.d_version =	D_VERSION,
-	.d_open =	mmopen,
-	.d_close =	mmclose,
-	.d_read =	mmrw,
-	.d_write =	mmrw,
-	.d_ioctl =	mmioctl,
-	.d_mmap =	memmmap,
-	.d_name =	"mem",
-	.d_maj =	CDEV_MAJOR,
-	.d_flags =	D_MEM | D_NEEDGIANT,
-};
-
-MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
+#include <machine/memdev.h>
 
 struct mem_range_softc mem_range_softc;
 
-static int
-mmclose(struct cdev *dev, int flags, int fmt, struct thread *td)
-{
-	switch (minor(dev)) {
-	case 14:
-		td->td_frame->tf_rflags &= ~PSL_IOPL;
-	}
-	return (0);
-}
-
-static int
-mmopen(struct cdev *dev, int flags, int fmt, struct thread *td)
-{
-	int error;
-
-	switch (minor(dev)) {
-	case 0:
-	case 1:
-		if (flags & FWRITE) {
-			error = securelevel_gt(td->td_ucred, 0);
-			if (error != 0)
-				return (error);
-		}
-		break;
-	case 14:
-		error = suser(td);
-		if (error != 0)
-			return (error);
-		error = securelevel_gt(td->td_ucred, 0);
-		if (error != 0)
-			return (error);
-		td->td_frame->tf_rflags |= PSL_IOPL;
-		break;
-	}
-	return (0);
-}
-
-/*ARGSUSED*/
-static int
-mmrw(struct cdev *dev, struct uio *uio, int flags)
+/* ARGSUSED */
+int
+memrw(struct cdev *dev, struct uio *uio, int flags)
 {
 	int o;
 	u_long c = 0, v;
@@ -149,22 +85,18 @@ mmrw(struct cdev *dev, struct uio *uio, int flags)
 			uio->uio_iov++;
 			uio->uio_iovcnt--;
 			if (uio->uio_iovcnt < 0)
-				panic("mmrw");
+				panic("memrw");
 			continue;
 		}
-		switch (minor(dev)) {
-
-/* minor device 0 is physical memory */
-		case 0:
+		if (minor(dev) == CDEV_MINOR_MEM) {
 			v = uio->uio_offset;
 kmemphys:
 			o = v & PAGE_MASK;
 			c = min(uio->uio_resid, (u_int)(PAGE_SIZE - o));
 			error = uiomove((void *)PHYS_TO_DMAP(v), (int)c, uio);
 			continue;
-
-/* minor device 1 is kernel memory */
-		case 1:
+		}
+		else if (minor(dev) == CDEV_MINOR_KMEM) {
 			v = uio->uio_offset;
 
 			if (v >= DMAP_MIN_ADDRESS && v < DMAP_MAX_ADDRESS) {
@@ -175,8 +107,9 @@ kmemphys:
 			c = iov->iov_len;
 
 			/*
-			 * Make sure that all of the pages are currently resident so
-			 * that we don't create any zero-fill pages.
+			 * Make sure that all of the pages are currently
+			 * resident so that we don't create any zero-fill
+			 * pages.
 			 */
 			addr = trunc_page(v);
 			eaddr = round_page(v + c);
@@ -194,44 +127,24 @@ kmemphys:
 
 			error = uiomove((caddr_t)(long)v, (int)c, uio);
 			continue;
-
-		default:
-			return (ENODEV);
 		}
-
-		if (error)
-			break;
-		iov->iov_base = (char *)iov->iov_base + c;
-		iov->iov_len -= c;
-		uio->uio_offset += c;
-		uio->uio_resid -= c;
+		/* else panic! */
 	}
 	return (error);
 }
 
-/*******************************************************\
-* allow user processes to MMAP some memory sections	*
-* instead of going through read/write			*
-\*******************************************************/
-static int
+/*
+ * allow user processes to MMAP some memory sections
+ * instead of going through read/write
+ */
+int
 memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
 {
-	switch (minor(dev))
-	{
-
-	/* minor device 0 is physical memory */
-	case 0:
+	if (minor(dev) == CDEV_MINOR_MEM)
 		*paddr = offset;
-		break;
-
-	/* minor device 1 is kernel memory */
-	case 1:
+	else if (minor(dev) == CDEV_MINOR_KMEM)
         	*paddr = vtophys(offset);
-		break;
-
-	default:
-		return (-1);
-	}
+	/* else panic! */
 	return (0);
 }
 
@@ -241,8 +154,9 @@ memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
  * This is basically just an ioctl shim for mem_range_attr_get
  * and mem_range_attr_set.
  */
-static int 
-mmioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td)
+int 
+memioctl(struct cdev *dev, 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;
@@ -331,37 +245,9 @@ mem_range_AP_init(void)
 }
 #endif
 
-static int
-mem_modevent(module_t mod, int type, void *data)
+void
+dev_mem_md_init(void)
 {
-	switch(type) {
-	case MOD_LOAD:
-		if (bootverbose)
-			printf("mem: <memory & I/O>\n");
-		/* Initialise memory range handling */
-		if (mem_range_softc.mr_op != NULL)
-			mem_range_softc.mr_op->init(&mem_range_softc);
-
-		memdev = make_dev(&mem_cdevsw, 0, UID_ROOT, GID_KMEM,
-			0640, "mem");
-		kmemdev = make_dev(&mem_cdevsw, 1, UID_ROOT, GID_KMEM,
-			0640, "kmem");
-		iodev = make_dev(&mem_cdevsw, 14, UID_ROOT, GID_WHEEL,
-			0600, "io");
-		return (0);
-
-	case MOD_UNLOAD:
-		destroy_dev(memdev);
-		destroy_dev(kmemdev);
-		destroy_dev(iodev);
-		return (0);
-
-	case MOD_SHUTDOWN:
-		return (0);
-
-	default:
-		return (EOPNOTSUPP);
-	}
+	if (mem_range_softc.mr_op != NULL)
+		mem_range_softc.mr_op->init(&mem_range_softc);
 }
-
-DEV_MODULE(mem, mem_modevent, NULL);
diff --git a/sys/amd64/conf/GENERIC b/sys/amd64/conf/GENERIC
index aa9848d..a6368d3 100644
--- a/sys/amd64/conf/GENERIC
+++ b/sys/amd64/conf/GENERIC
@@ -217,8 +217,10 @@ device		awi		# BayStack 660 and others
 device		wi		# WaveLAN/Intersil/Symbol 802.11 wireless NICs.
 
 # Pseudo devices.
-device		random		# Entropy device
 device		loop		# Network loopback
+device		mem		# Memory and kernel memory devices
+device		null		# Null and zero devices
+device		random		# Entropy device
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
 device		ppp		# Kernel PPP
diff --git a/sys/amd64/conf/NOTES b/sys/amd64/conf/NOTES
index d3610a6..b21160c 100644
--- a/sys/amd64/conf/NOTES
+++ b/sys/amd64/conf/NOTES
@@ -517,3 +517,7 @@ options 	TIMER_FREQ=((14318182+6)/12)
 options 	VM_KMEM_SIZE
 options 	VM_KMEM_SIZE_MAX
 options 	VM_KMEM_SIZE_SCALE
+
+
+# The I/O device
+device		io
diff --git a/sys/amd64/include/iodev.h b/sys/amd64/include/iodev.h
new file mode 100644
index 0000000..2273620
--- /dev/null
+++ b/sys/amd64/include/iodev.h
@@ -0,0 +1,33 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#define CDEV_MAJOR	2
+#define CDEV_MINOR_IO	14
+
+d_open_t	ioopen;
+d_close_t	ioclose;
diff --git a/sys/amd64/include/memdev.h b/sys/amd64/include/memdev.h
new file mode 100644
index 0000000..b6d3122
--- /dev/null
+++ b/sys/amd64/include/memdev.h
@@ -0,0 +1,38 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#define CDEV_MAJOR	2
+#define	CDEV_MINOR_MEM	0
+#define	CDEV_MINOR_KMEM	1
+
+d_open_t	memopen;
+d_read_t	memrw;
+d_ioctl_t	memioctl;
+d_mmap_t	memmmap;
+
+void		dev_mem_md_init(void);
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index 40d23b4..c919e31 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -836,9 +836,15 @@ options 	EXT2FS
 # unsuitable for inclusion on machines with untrusted local users.
 options 	VFS_AIO
 
-# Cryptographically secure random number generator; /dev/[u]random
+# Cryptographically secure random number generator; /dev/random
 device		random
 
+# The bit-bucket; /dev/null
+device		null
+
+# The system memory devices; /dev/mem, /dev/kmem
+device		mem
+
 # Optional character code conversion support with LIBICONV.
 # Each option requires their base file system and LIBICONV.
 options 	CD9660_ICONV
diff --git a/sys/conf/files b/sys/conf/files
index ab5ff56..b84fdaf 100644
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -545,6 +545,7 @@ dev/mca/mca_bus.c	optional mca
 dev/mcd/mcd.c		optional mcd isa nowerror
 dev/mcd/mcd_isa.c	optional mcd isa nowerror
 dev/md/md.c		optional md
+dev/mem/memdev.c	optional mem
 dev/mii/amphy.c		optional miibus
 dev/mii/bmtphy.c	optional miibus
 dev/mii/brgphy.c	optional miibus
@@ -583,8 +584,8 @@ dev/mpt/mpt_pci.c	optional mpt pci
 dev/my/if_my.c		optional my
 dev/musycc/musycc.c	optional musycc
 dev/nge/if_nge.c	optional nge
-dev/null/null.c		standard
 dev/nmdm/nmdm.c		optional nmdm
+dev/null/null.c		optional null
 dev/patm/if_patm.c	optional patm pci
 dev/patm/if_patm_intr.c	optional patm pci
 dev/patm/if_patm_ioctl.c	optional patm pci
diff --git a/sys/conf/files.alpha b/sys/conf/files.alpha
index 73f166d..6b3553b 100644
--- a/sys/conf/files.alpha
+++ b/sys/conf/files.alpha
@@ -71,7 +71,7 @@ alpha/alpha/in_cksum.c		optional	inet
 alpha/alpha/interrupt.c		standard
 alpha/alpha/locore.s		standard	no-obj
 alpha/alpha/machdep.c		standard
-alpha/alpha/mem.c		standard
+alpha/alpha/mem.c		optional	mem
 alpha/alpha/pmap.c		standard
 alpha/alpha/mp_machdep.c	optional	smp
 alpha/alpha/prom.c		standard
diff --git a/sys/conf/files.amd64 b/sys/conf/files.amd64
index 2147cce..74a254a 100644
--- a/sys/conf/files.amd64
+++ b/sys/conf/files.amd64
@@ -59,12 +59,13 @@ amd64/amd64/identcpu.c		standard
 amd64/amd64/in_cksum.c		optional	inet
 amd64/amd64/initcpu.c		standard
 amd64/amd64/intr_machdep.c	standard
+amd64/amd64/io.c		optional	io
 amd64/amd64/io_apic.c		standard
 amd64/amd64/legacy.c		standard
 amd64/amd64/local_apic.c	standard
 amd64/amd64/locore.S		standard	no-obj
 amd64/amd64/machdep.c		standard
-amd64/amd64/mem.c		standard
+amd64/amd64/mem.c		optional	mem
 amd64/amd64/mp_machdep.c	optional	smp
 amd64/amd64/mpboot.S		optional	smp
 amd64/amd64/mptable.c		optional	mptable
@@ -100,6 +101,7 @@ dev/fb/fb.c			optional	fb
 dev/fb/fb.c			optional	vga
 dev/fb/splash.c			optional	splash
 dev/fb/vga.c			optional	vga
+dev/io/iodev.c			optional	io
 dev/fdc/fdc.c			optional	fdc
 dev/fdc/fdc_acpi.c		optional	fdc
 dev/fdc/fdc_isa.c		optional	fdc isa
diff --git a/sys/conf/files.i386 b/sys/conf/files.i386
index d569b44..b5aa266 100644
--- a/sys/conf/files.i386
+++ b/sys/conf/files.i386
@@ -152,6 +152,7 @@ dev/kbd/kbd.c			optional	sc
 dev/kbd/kbd.c			optional	ukbd
 dev/kbd/kbd.c			optional	vt
 dev/lnc/if_lnc_isa.c		optional	lnc isa
+dev/io/iodev.c			optional	io
 dev/ppc/ppc.c			optional	ppc
 dev/ppc/ppc_puc.c		optional	ppc puc pci
 dev/random/nehemiah.c		optional	random
@@ -216,19 +217,20 @@ i386/i386/elf_machdep.c		standard
 i386/i386/exception.s		standard
 i386/i386/gdb_machdep.c		optional	gdb
 i386/i386/geode.c		optional	cpu_geode
-i386/i386/i686_mem.c		standard
+i386/i386/i686_mem.c		optional	mem
 i386/i386/identcpu.c		standard
 i386/i386/in_cksum.c		optional	inet
 i386/i386/initcpu.c		standard
 i386/i386/intr_machdep.c	standard
 i386/i386/io_apic.c		optional	apic
-i386/i386/k6_mem.c		standard
+i386/i386/io.c			optional	io
+i386/i386/k6_mem.c		optional	mem
 i386/i386/legacy.c		standard
 i386/i386/local_apic.c		optional	apic
 i386/i386/locore.s		standard	no-obj
 i386/i386/longrun.c		optional	cpu_enable_longrun
 i386/i386/machdep.c		standard
-i386/i386/mem.c			standard
+i386/i386/mem.c			optional	mem
 i386/i386/mp_clock.c		optional	smp
 i386/i386/mp_machdep.c		optional	smp
 i386/i386/mpboot.s		optional	smp
diff --git a/sys/conf/files.ia64 b/sys/conf/files.ia64
index b4d2e94..8d1ccab 100644
--- a/sys/conf/files.ia64
+++ b/sys/conf/files.ia64
@@ -104,7 +104,7 @@ ia64/ia64/interrupt.c		standard
 ia64/ia64/locore.S		standard	no-obj
 ia64/ia64/machdep.c		standard
 ia64/ia64/mca.c			standard
-ia64/ia64/mem.c			standard
+ia64/ia64/mem.c			optional	mem
 ia64/ia64/mp_machdep.c		optional	smp
 ia64/ia64/nexus.c		standard
 ia64/ia64/pal.S			standard
diff --git a/sys/conf/files.pc98 b/sys/conf/files.pc98
index 3a377b7..bfb08a7 100644
--- a/sys/conf/files.pc98
+++ b/sys/conf/files.pc98
@@ -157,7 +157,7 @@ i386/i386/k6_mem.c		standard
 i386/i386/legacy.c		standard
 i386/i386/local_apic.c		optional	apic
 i386/i386/locore.s		standard	no-obj
-i386/i386/mem.c			standard
+i386/i386/mem.c			optional	mem
 i386/i386/mp_clock.c		optional	smp
 i386/i386/mp_machdep.c		optional	smp
 i386/i386/mpboot.s		optional	smp
diff --git a/sys/conf/files.sparc64 b/sys/conf/files.sparc64
index 878930e..148483e 100644
--- a/sys/conf/files.sparc64
+++ b/sys/conf/files.sparc64
@@ -88,7 +88,7 @@ sparc64/sparc64/intr_machdep.c	standard
 sparc64/sparc64/iommu.c		standard
 sparc64/sparc64/locore.S	standard	no-obj
 sparc64/sparc64/machdep.c	standard
-sparc64/sparc64/mem.c		standard
+sparc64/sparc64/mem.c		optional	mem
 sparc64/sparc64/mp_exception.S	optional	smp
 sparc64/sparc64/mp_locore.S	optional	smp
 sparc64/sparc64/mp_machdep.c	optional	smp
diff --git a/sys/dev/io/iodev.c b/sys/dev/io/iodev.c
new file mode 100644
index 0000000..d1b3170
--- /dev/null
+++ b/sys/dev/io/iodev.c
@@ -0,0 +1,89 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/conf.h>
+#include <sys/fcntl.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/signalvar.h>
+#include <sys/systm.h>
+#include <sys/uio.h>
+
+#include <machine/specialreg.h>
+
+#include <vm/vm.h>
+#include <vm/pmap.h>
+
+#include <machine/iodev.h>
+
+static struct cdev *iodev;
+
+static struct cdevsw io_cdevsw = {
+	.d_version =	D_VERSION,
+	.d_flags =	D_NEEDGIANT,
+	.d_open =	ioopen,
+	.d_close =	ioclose,
+	.d_name =	"io",
+};
+
+/* ARGSUSED */
+static int
+io_modevent(module_t mod __unused, int type, void *data __unused)
+{
+	switch(type) {
+	case MOD_LOAD:
+		if (bootverbose)
+			printf("io: <I/O>\n");
+		iodev = make_dev(&io_cdevsw, CDEV_MINOR_IO,
+			UID_ROOT, GID_WHEEL, 0600, "io");
+		break;
+
+	case MOD_UNLOAD:
+		destroy_dev(iodev);
+		break;
+
+	case MOD_SHUTDOWN:
+		break;
+
+	default:
+		return(EOPNOTSUPP);
+		break;
+
+	}
+
+	return (0);
+}
+
+DEV_MODULE(io, io_modevent, NULL);
diff --git a/sys/dev/mem/memdev.c b/sys/dev/mem/memdev.c
new file mode 100644
index 0000000..290259a
--- /dev/null
+++ b/sys/dev/mem/memdev.c
@@ -0,0 +1,108 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/conf.h>
+#include <sys/fcntl.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/memrange.h>
+#include <sys/module.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/signalvar.h>
+#include <sys/systm.h>
+#include <sys/uio.h>
+
+#include <vm/vm.h>
+#include <vm/pmap.h>
+
+#include <machine/memdev.h>
+
+static struct cdev *memdev, *kmemdev;
+
+static struct cdevsw mem_cdevsw = {
+	.d_version =	D_VERSION,
+	.d_flags =	D_MEM|D_NEEDGIANT,
+	.d_open =	memopen,
+	.d_read =	memrw,
+	.d_write =	memrw,
+	.d_ioctl =	memioctl,
+	.d_mmap =	memmmap,
+	.d_name =	"mem",
+};
+
+/* ARGSUSED */
+int
+memopen(struct cdev *dev __unused, int flags, int fmt __unused,
+    struct thread *td)
+{
+	int error = 0;
+
+	if (flags & FWRITE)
+		error = securelevel_gt(td->td_ucred, 0);
+
+	return (error);
+}
+
+/* ARGSUSED */
+static int
+mem_modevent(module_t mod __unused, int type, void *data __unused)
+{
+	switch(type) {
+	case MOD_LOAD:
+		if (bootverbose)
+			printf("mem: <memory>\n");
+		dev_mem_md_init(); /* Machine dependant bit */
+		memdev = make_dev(&mem_cdevsw, CDEV_MINOR_MEM,
+			UID_ROOT, GID_KMEM, 0640, "mem");
+		kmemdev = make_dev(&mem_cdevsw, CDEV_MINOR_KMEM,
+			UID_ROOT, GID_KMEM, 0640, "kmem");
+		break;
+
+	case MOD_UNLOAD:
+		destroy_dev(memdev);
+		destroy_dev(kmemdev);
+		break;
+
+	case MOD_SHUTDOWN:
+		break;
+
+	default:
+		return(EOPNOTSUPP);
+		break;
+
+	}
+
+	return (0);
+}
+
+DEV_MODULE(mem, mem_modevent, NULL);
diff --git a/sys/dev/null/null.c b/sys/dev/null/null.c
index 4f7bd9c..653d732 100644
--- a/sys/dev/null/null.c
+++ b/sys/dev/null/null.c
@@ -43,14 +43,17 @@ __FBSDID("$FreeBSD$");
 /* For use with destroy_dev(9). */
 static struct cdev *null_dev;
 static struct cdev *zero_dev;
+static struct cdev *full_dev;
 
 static d_write_t null_write;
 static d_ioctl_t null_ioctl;
 static d_read_t zero_read;
+static d_write_t full_write;
 
 #define CDEV_MAJOR	2
-#define NULL_MINOR	2
-#define ZERO_MINOR	12
+#define NULL_MINOR	0
+#define ZERO_MINOR	1
+#define FULL_MINOR	2
 
 static struct cdevsw null_cdevsw = {
 	.d_version =	D_VERSION,
@@ -70,6 +73,14 @@ static struct cdevsw zero_cdevsw = {
 	.d_flags =	D_MMAP_ANON,
 };
 
+static struct cdevsw full_cdevsw = {
+	.d_version =	D_VERSION,
+	.d_read =	(d_read_t *)nullop,
+	.d_write =	full_write,
+	.d_name =	"full",
+	.d_maj =	CDEV_MAJOR,
+};
+
 static void *zbuf;
 
 /* ARGSUSED */
@@ -100,19 +111,23 @@ null_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t data __unused,
 static int
 zero_read(struct cdev *dev __unused, struct uio *uio, int flags __unused)
 {
-	int c;
 	int error = 0;
 
-	while (uio->uio_resid > 0 && error == 0) {
-		c = uio->uio_resid < PAGE_SIZE ? uio->uio_resid : PAGE_SIZE;
-		error = uiomove(zbuf, c, uio);
-	}
+	while (uio->uio_resid > 0 && error == 0)
+		error = uiomove(zbuf, MIN(uio->uio_resid, PAGE_SIZE), uio);
 
 	return (error);
 }
 
 /* ARGSUSED */
 static int
+full_write(struct cdev *dev __unused, struct uio *uio, int flags __unused)
+{
+	return (ENOSPC);
+}
+
+/* ARGSUSED */
+static int
 null_modevent(module_t mod __unused, int type, void *data __unused)
 {
 	switch(type) {
@@ -120,15 +135,18 @@ null_modevent(module_t mod __unused, int type, void *data __unused)
 		if (bootverbose)
 			printf("null: <null device, zero device>\n");
 		zbuf = (void *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK | M_ZERO);
-		zero_dev = make_dev(&zero_cdevsw, ZERO_MINOR, UID_ROOT,
-			GID_WHEEL, 0666, "zero");
 		null_dev = make_dev(&null_cdevsw, NULL_MINOR, UID_ROOT,
 			GID_WHEEL, 0666, "null");
+		zero_dev = make_dev(&zero_cdevsw, ZERO_MINOR, UID_ROOT,
+			GID_WHEEL, 0666, "zero");
+		full_dev = make_dev(&full_cdevsw, FULL_MINOR, UID_ROOT,
+			GID_WHEEL, 0666, "full");
 		break;
 
 	case MOD_UNLOAD:
 		destroy_dev(null_dev);
 		destroy_dev(zero_dev);
+		destroy_dev(full_dev);
 		free(zbuf, M_TEMP);
 		break;
 
diff --git a/sys/i386/conf/GENERIC b/sys/i386/conf/GENERIC
index 3fce0da..f8ae817 100644
--- a/sys/i386/conf/GENERIC
+++ b/sys/i386/conf/GENERIC
@@ -29,7 +29,7 @@ ident		GENERIC
 
 makeoptions	DEBUG=-g		# Build kernel with gdb(1) debug symbols
 
-options 	SCHED_ULE		# ULE scheduler
+options 	SCHED_4BSD
 options 	INET			# InterNETworking
 options 	INET6			# IPv6 communications protocols
 options 	FFS			# Berkeley Fast Filesystem
@@ -239,8 +239,10 @@ device		wi		# WaveLAN/Intersil/Symbol 802.11 wireless NICs.
 #device		wl		# Older non 802.11 Wavelan wireless NIC.
 
 # Pseudo devices.
-device		random		# Entropy device
 device		loop		# Network loopback
+device		mem		# Memory and kernel memory devices
+device		null		# Null and zero devices
+device		random		# Entropy device
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
 device		ppp		# Kernel PPP
diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES
index c1d05f5..6a6b4e6 100644
--- a/sys/i386/conf/NOTES
+++ b/sys/i386/conf/NOTES
@@ -1053,3 +1053,7 @@ options 	TIMER_FREQ=((14318182+6)/12)
 options 	VM_KMEM_SIZE
 options 	VM_KMEM_SIZE_MAX
 options 	VM_KMEM_SIZE_SCALE
+
+
+# The I/O device
+device		io
diff --git a/sys/i386/i386/io.c b/sys/i386/i386/io.c
new file mode 100644
index 0000000..1c0866d
--- /dev/null
+++ b/sys/i386/i386/io.c
@@ -0,0 +1,77 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/conf.h>
+#include <sys/fcntl.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/mutex.h>
+#include <sys/proc.h>
+#include <sys/signalvar.h>
+#include <sys/systm.h>
+
+#include <machine/db_machdep.h>
+#include <machine/frame.h>
+#include <machine/psl.h>
+#include <machine/specialreg.h>
+
+#include <vm/vm.h>
+#include <vm/pmap.h>
+
+#include <machine/iodev.h>
+
+/* ARGSUSED */
+int
+ioopen(struct cdev *dev __unused, int flags __unused, int fmt __unused,
+    struct thread *td)
+{
+	int error;
+
+	error = suser(td);
+	if (error != 0)
+		return (error);
+	error = securelevel_gt(td->td_ucred, 0);
+	if (error != 0)
+		return (error);
+
+	td->td_frame->tf_eflags |= PSL_IOPL;
+
+	return (0);
+}
+
+/* ARGSUSED */
+int
+ioclose(struct cdev *dev __unused, int flags __unused, int fmt __unused,
+    struct thread *td)
+{
+	td->td_frame->tf_eflags &= ~PSL_IOPL;
+
+	return (0);
+}
diff --git a/sys/i386/i386/mem.c b/sys/i386/i386/mem.c
index 379b59c..444499c 100644
--- a/sys/i386/i386/mem.c
+++ b/sys/i386/i386/mem.c
@@ -58,81 +58,31 @@ __FBSDID("$FreeBSD$");
 #include <sys/systm.h>
 #include <sys/uio.h>
 
-#include <machine/db_machdep.h>
-#include <machine/frame.h>
-#include <machine/psl.h>
 #include <machine/specialreg.h>
 
 #include <vm/vm.h>
 #include <vm/pmap.h>
 #include <vm/vm_extern.h>
 
-static struct cdev *memdev, *kmemdev, *iodev;
-
-static	d_open_t	mmopen;
-static	d_close_t	mmclose;
-static	d_read_t	mmrw;
-static	d_ioctl_t	mmioctl;
-static	d_mmap_t	memmmap;
-
-#define CDEV_MAJOR 2
-static struct cdevsw mem_cdevsw = {
-	.d_version =	D_VERSION,
-	.d_open =	mmopen,
-	.d_close =	mmclose,
-	.d_read =	mmrw,
-	.d_write =	mmrw,
-	.d_ioctl =	mmioctl,
-	.d_mmap =	memmmap,
-	.d_name =	"mem",
-	.d_maj =	CDEV_MAJOR,
-	.d_flags =	D_MEM | D_NEEDGIANT,
-};
+#include <machine/memdev.h>
 
+/*
+ * Used in /dev/mem drivers and elsewhere
+ */
 MALLOC_DEFINE(M_MEMDESC, "memdesc", "memory range descriptors");
-
 struct mem_range_softc mem_range_softc;
 
-static int
-mmclose(struct cdev *dev, int flags, int fmt, struct thread *td)
+void
+mem_range_AP_init(void)
 {
-	switch (minor(dev)) {
-	case 14:
-		td->td_frame->tf_eflags &= ~PSL_IOPL;
-	}
-	return (0);
+	if (mem_range_softc.mr_op && mem_range_softc.mr_op->initAP)
+		mem_range_softc.mr_op->initAP(&mem_range_softc);
 }
 
-static int
-mmopen(struct cdev *dev, int flags, int fmt, struct thread *td)
-{
-	int error;
 
-	switch (minor(dev)) {
-	case 0:
-	case 1:
-		if (flags & FWRITE) {
-			error = securelevel_gt(td->td_ucred, 0);
-			if (error != 0)
-				return (error);
-		}
-		break;
-	case 14:
-		error = suser(td);
-		if (error != 0)
-			return (error);
-		error = securelevel_gt(td->td_ucred, 0);
-		if (error != 0)
-			return (error);
-		td->td_frame->tf_eflags |= PSL_IOPL;
-		break;
-	}
-	return (0);
-}
-
-/*ARGSUSED*/
-static int
-mmrw(struct cdev *dev, struct uio *uio, int flags)
+/* ARGSUSED */
+int
+memrw(struct cdev *dev, struct uio *uio, int flags)
 {
 	int o;
 	u_int c = 0, v;
@@ -148,13 +98,10 @@ mmrw(struct cdev *dev, struct uio *uio, int flags)
 			uio->uio_iov++;
 			uio->uio_iovcnt--;
 			if (uio->uio_iovcnt < 0)
-				panic("mmrw");
+				panic("memrw");
 			continue;
 		}
-		switch (minor(dev)) {
-
-/* minor device 0 is physical memory */
-		case 0:
+		if (minor(dev) == CDEV_MINOR_MEM) {
 			v = uio->uio_offset;
 			v &= ~PAGE_MASK;
 			pmap_kenter((vm_offset_t)ptvmmap, v);
@@ -165,14 +112,14 @@ mmrw(struct cdev *dev, struct uio *uio, int flags)
 			error = uiomove((caddr_t)&ptvmmap[o], (int)c, uio);
 			pmap_qremove((vm_offset_t)ptvmmap, 1);
 			continue;
-
-/* minor device 1 is kernel memory */
-		case 1:
+		}
+		else if (minor(dev) == CDEV_MINOR_KMEM) {
 			c = iov->iov_len;
 
 			/*
-			 * Make sure that all of the pages are currently resident so
-			 * that we don't create any zero-fill pages.
+			 * Make sure that all of the pages are currently
+			 * resident so that we don't create any zero-fill
+			 * pages.
 			 */
 			addr = trunc_page(uio->uio_offset);
 			eaddr = round_page(uio->uio_offset + c);
@@ -189,44 +136,26 @@ mmrw(struct cdev *dev, struct uio *uio, int flags)
 				return (EFAULT);
 			error = uiomove((caddr_t)(int)uio->uio_offset, (int)c, uio);
 			continue;
-
-		default:
-			return (ENODEV);
 		}
-
-		if (error)
-			break;
-		iov->iov_base = (char *)iov->iov_base + c;
-		iov->iov_len -= c;
-		uio->uio_offset += c;
-		uio->uio_resid -= c;
+		/* else panic! */
 	}
 	return (error);
 }
 
-/*******************************************************\
-* allow user processes to MMAP some memory sections	*
-* instead of going through read/write			*
-\*******************************************************/
-static int
-memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
+/*
+ * allow user processes to MMAP some memory sections
+ * instead of going through read/write
+ */
+/* ARGSUSED */
+int
+memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr,
+    int prot __unused)
 {
-	switch (minor(dev))
-	{
-
-	/* minor device 0 is physical memory */
-	case 0:
+	if (minor(dev) == CDEV_MINOR_MEM)
 		*paddr = offset;
-		break;
-
-	/* minor device 1 is kernel memory */
-	case 1:
+	else if (minor(dev) == CDEV_MINOR_KMEM)
         	*paddr = vtophys(offset);
-		break;
-
-	default:
-		return (-1);
-	}
+	/* else panic! */
 	return (0);
 }
 
@@ -236,8 +165,10 @@ memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
  * This is basically just an ioctl shim for mem_range_attr_get
  * and mem_range_attr_set.
  */
-static int 
-mmioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td)
+/* 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;
@@ -317,46 +248,9 @@ mem_range_attr_set(struct mem_range_desc *mrd, int *arg)
 	return (mem_range_softc.mr_op->set(&mem_range_softc, mrd, arg));
 }
 
-#ifdef SMP
 void
-mem_range_AP_init(void)
+dev_mem_md_init(void)
 {
-	if (mem_range_softc.mr_op && mem_range_softc.mr_op->initAP)
-		(mem_range_softc.mr_op->initAP(&mem_range_softc));
+	if (mem_range_softc.mr_op != NULL)
+		mem_range_softc.mr_op->init(&mem_range_softc);
 }
-#endif
-
-static int
-mem_modevent(module_t mod, int type, void *data)
-{
-	switch(type) {
-	case MOD_LOAD:
-		if (bootverbose)
-			printf("mem: <memory & I/O>\n");
-		/* Initialise memory range handling */
-		if (mem_range_softc.mr_op != NULL)
-			mem_range_softc.mr_op->init(&mem_range_softc);
-
-		memdev = make_dev(&mem_cdevsw, 0, UID_ROOT, GID_KMEM,
-			0640, "mem");
-		kmemdev = make_dev(&mem_cdevsw, 1, UID_ROOT, GID_KMEM,
-			0640, "kmem");
-		iodev = make_dev(&mem_cdevsw, 14, UID_ROOT, GID_WHEEL,
-			0600, "io");
-		return (0);
-
-	case MOD_UNLOAD:
-		destroy_dev(memdev);
-		destroy_dev(kmemdev);
-		destroy_dev(iodev);
-		return (0);
-
-	case MOD_SHUTDOWN:
-		return (0);
-
-	default:
-		return (EOPNOTSUPP);
-	}
-}
-
-DEV_MODULE(mem, mem_modevent, NULL);
diff --git a/sys/i386/include/iodev.h b/sys/i386/include/iodev.h
new file mode 100644
index 0000000..2273620
--- /dev/null
+++ b/sys/i386/include/iodev.h
@@ -0,0 +1,33 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#define CDEV_MAJOR	2
+#define CDEV_MINOR_IO	14
+
+d_open_t	ioopen;
+d_close_t	ioclose;
diff --git a/sys/i386/include/memdev.h b/sys/i386/include/memdev.h
new file mode 100644
index 0000000..4443e36
--- /dev/null
+++ b/sys/i386/include/memdev.h
@@ -0,0 +1,40 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#define CDEV_MAJOR	2
+#define	CDEV_MINOR_MEM	0
+#define	CDEV_MINOR_KMEM	1
+
+d_open_t	memopen;
+d_read_t	memrw;
+d_ioctl_t	memioctl;
+d_mmap_t	memmmap;
+
+void		dev_mem_md_init(void);
+
+MALLOC_DECLARE(M_MEMDEV);
diff --git a/sys/ia64/conf/GENERIC b/sys/ia64/conf/GENERIC
index 859cd9d..f19dfc3 100644
--- a/sys/ia64/conf/GENERIC
+++ b/sys/ia64/conf/GENERIC
@@ -140,6 +140,8 @@ device		loop		# Network loopback
 device		md		# Memory "disks"
 device		pty		# Pseudo-ttys (telnet etc)
 device		puc		# Multi I/O cards and multi-channel UARTs
+device		null		# Null and zero devices
+device		mem		# Memory and kernel memory devices
 device		random		# Entropy device
 device		tun		# Packet tunnel.
 device		uart		# Serial port (UART)
diff --git a/sys/ia64/ia64/mem.c b/sys/ia64/ia64/mem.c
index d03051f..79c97ee 100644
--- a/sys/ia64/ia64/mem.c
+++ b/sys/ia64/ia64/mem.c
@@ -34,9 +34,11 @@
  *
  *	from: Utah $Hdr: mem.c 1.13 89/10/08$
  *	from: @(#)mem.c	7.2 (Berkeley) 5/9/91
- * $FreeBSD$
  */
 
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
 /*
  * Memory special file
  */
@@ -58,38 +60,12 @@
 
 #include <machine/cpu.h>
 #include <machine/frame.h>
-#ifdef PERFMON
-#include <machine/perfmon.h>
-#endif
 
 #include <vm/vm.h>
 #include <vm/pmap.h>
 #include <vm/vm_extern.h>
 
-static struct cdev *memdev, *kmemdev;
-#ifdef PERFMON
-static struct cdev *perfdev;
-#endif /* PERFMON */
-
-static	d_open_t	mmopen;
-static	d_close_t	mmclose;
-static	d_read_t	mmrw;
-static	d_ioctl_t	mmioctl;
-static	d_mmap_t	memmmap;
-
-#define CDEV_MAJOR 2
-static struct cdevsw mem_cdevsw = {
-	.d_version =	D_VERSION,
-	.d_open =	mmopen,
-	.d_close =	mmclose,
-	.d_read =	mmrw,
-	.d_write =	mmrw,
-	.d_ioctl =	mmioctl,
-	.d_mmap =	memmmap,
-	.d_name =	"mem",
-	.d_maj =	CDEV_MAJOR,
-	.d_flags =	D_MEM | D_NEEDGIANT,
-};
+#include <machine/memdev.h>
 
 struct mem_range_softc mem_range_softc;
 
@@ -99,49 +75,9 @@ ia64_pa_access(vm_offset_t pa)
 	return (VM_PROT_READ|VM_PROT_WRITE);
 }
 
-static int
-mmclose(struct cdev *dev, int flags, int fmt, struct thread *td)
-{
-	switch (minor(dev)) {
-#ifdef PERFMON
-	case 32:
-		return perfmon_close(dev, flags, fmt, td);
-#endif
-	default:
-		break;
-	}
-	return (0);
-}
-
-static int
-mmopen(struct cdev *dev, int flags, int fmt, struct thread *td)
-{
-	int error;
-
-	switch (minor(dev)) {
-	case 0:
-	case 1:
-		if (flags & FWRITE) {
-			error = securelevel_gt(td->td_ucred, 0);
-			if (error)
-				return error;
-		}
-		break;
-	case 32:
-#ifdef PERFMON
-		return perfmon_open(dev, flags, fmt, td);
-#else
-		return ENODEV;
-#endif
-	default:
-		break;
-	}
-	return (0);
-}
-
-/*ARGSUSED*/
-static int
-mmrw(struct cdev *dev, struct uio *uio, int flags)
+/* ARGSUSED */
+int
+memrw(strct cdev *dev, struct uio *uio, int flags)
 {
 	struct iovec *iov;
 	vm_offset_t addr, eaddr, o, v;
@@ -154,14 +90,11 @@ mmrw(struct cdev *dev, struct uio *uio, int flags)
 			uio->uio_iov++;
 			uio->uio_iovcnt--;
 			if (uio->uio_iovcnt < 0)
-				panic("mmrw");
+				panic("memrw");
 			continue;
 		}
 
-		switch (minor(dev)) {
-
-/* minor device 0 is physical memory */
-		case 0:
+		if (minor(dev) == CDEV_MINOR_MEM) {
 			v = uio->uio_offset;
 kmemphys:
 			/* Allow reads only in RAM. */
@@ -177,9 +110,8 @@ kmemphys:
 			c = min(uio->uio_resid, (int)(PAGE_SIZE - o));
 			error = uiomove((caddr_t)IA64_PHYS_TO_RR7(v), c, uio);
 			continue;
-
-/* minor device 1 is kernel memory */
-		case 1:
+		}
+		else if (minor(dev) == CDEV_MINOR_KMEM) {
 			v = uio->uio_offset;
 
 			if (v >= IA64_RR_BASE(6)) {
@@ -205,27 +137,18 @@ kmemphys:
 				return (EFAULT);
 			error = uiomove((caddr_t)v, c, uio);
 			continue;
-
-		default:
-			return (ENODEV);
 		}
-
-		if (error)
-			break;
-		iov->iov_base = (char *)iov->iov_base + c;
-		iov->iov_len -= c;
-		uio->uio_offset += c;
-		uio->uio_resid -= c;
+		/* else panic! */
 	}
 	return (error);
 }
 
-/*******************************************************\
-* allow user processes to MMAP some memory sections	*
-* instead of going through read/write			*
-\*******************************************************/
-static int
-memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
+/*
+ * allow user processes to MMAP some memory sections
+ * instead of going through read/write
+ */
+int
+memmmap(strct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
 {
 	/*
 	 * /dev/mem is the only one that makes sense through this
@@ -233,7 +156,7 @@ memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
 	 * could be transient and hence incorrect or invalid at
 	 * a later time.
 	 */
-	if (minor(dev) != 0)
+	if (minor(dev) != CDEV_MINOR_MEM)
 		return (-1);
 
 	/*
@@ -245,59 +168,7 @@ memmmap(struct cdev *dev, vm_offset_t offset, vm_paddr_t *paddr, int prot)
 	return (0);
 }
 
-static int
-mmioctl(struct cdev *dev, u_long cmd, caddr_t cmdarg, int flags, struct thread *td)
+void
+dev_mem_md_init(void)
 {
-	switch(minor(dev)) {
-#ifdef PERFMON
-	case 32:
-		return perfmon_ioctl(dev, cmd, cmdarg, flags, td);
-#endif
-	default:
-		return ENODEV;
-	}
-
-	return (0);
 }
-
-static int
-mem_modevent(module_t mod, int type, void *data)
-{
-	switch(type) {
-	case MOD_LOAD:
-		if (bootverbose)
-			printf("mem: <memory & I/O>\n");
-/* XXX - ??? */
-#if 0
-		/* Initialise memory range handling */
-		if (mem_range_softc.mr_op != NULL)
-			mem_range_softc.mr_op->init(&mem_range_softc);
-#endif
-
-		memdev = make_dev(&mem_cdevsw, 0, UID_ROOT, GID_KMEM,
-			0640, "mem");
-		kmemdev = make_dev(&mem_cdevsw, 1, UID_ROOT, GID_KMEM,
-			0640, "kmem");
-#ifdef PERFMON
-		perfdev = make_dev(&mem_cdevsw, 32, UID_ROOT, GID_KMEM,
-			0640, "perfmon");
-#endif /* PERFMON */
-		return 0;
-
-	case MOD_UNLOAD:
-		destroy_dev(memdev);
-		destroy_dev(kmemdev);
-#ifdef PERFMON
-		destroy_dev(perfdev);
-#endif /* PERFMON */
-		return 0;
-
-	case MOD_SHUTDOWN:
-		return 0;
-
-	default:
-		return EOPNOTSUPP;
-	}
-}
-
-DEV_MODULE(mem, mem_modevent, NULL);
diff --git a/sys/ia64/include/memdev.h b/sys/ia64/include/memdev.h
new file mode 100644
index 0000000..e2ec491
--- /dev/null
+++ b/sys/ia64/include/memdev.h
@@ -0,0 +1,38 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#define CDEV_MAJOR	2
+#define	CDEV_MINOR_MEM	0
+#define	CDEV_MINOR_KMEM	1
+
+d_open_t	memopen;
+d_read_t	memrw;
+#define		memioctl	(d_ioctl_t *)NULL;
+d_mmap_t	memmmap;
+
+void		dev_mem_md_init(void);
diff --git a/sys/modules/Makefile b/sys/modules/Makefile
index 98052a7..938c4c8 100644
--- a/sys/modules/Makefile
+++ b/sys/modules/Makefile
@@ -101,6 +101,7 @@ SUBDIR=	${_3dfx} \
 	if_tun \
 	if_vlan \
 	${_iir} \
+	${_io} \
 	ip6fw \
 	${_ipfilter} \
 	ipfw \
@@ -131,6 +132,7 @@ SUBDIR=	${_3dfx} \
 	mac_test \
 	mcd \
 	md \
+	mem \
 	mii \
 	mlx \
 	${_mly} \
@@ -149,7 +151,7 @@ SUBDIR=	${_3dfx} \
 	${_nsp} \
 	ntfs \
 	ntfs_iconv \
-	${_null} \
+	null \
 	nullfs \
 	${_nwfs} \
 	${_oltr} \
@@ -252,7 +254,6 @@ _syscons=	syscons
 .endif
 
 .if defined(ALL_MODULES)
-_null=		null
 _ufs=		ufs
 .endif
 
@@ -301,6 +302,7 @@ _hfa=		hfa
 _i2c=		i2c
 _ibcs2=		ibcs2
 _ie=		ie
+_io=		io
 _linprocfs=	linprocfs
 _linux=		linux
 _lnc=		lnc
@@ -374,6 +376,7 @@ _sppp=		sppp
 .endif
 
 .if ${MACHINE_ARCH} == "amd64"
+_io=		io
 #_ndis=		ndis
 .endif
 
diff --git a/sys/modules/io/Makefile b/sys/modules/io/Makefile
new file mode 100644
index 0000000..ffb3442
--- /dev/null
+++ b/sys/modules/io/Makefile
@@ -0,0 +1,10 @@
+# $FreeBSD$
+
+.PATH: ${.CURDIR}/../../dev/io
+.PATH: ${.CURDIR}/../../${MACHINE_ARCH}/${MACHINE_ARCH}
+
+KMOD=	io
+SRCS=	iodev.c io.c
+SRCS+=	bus_if.h device_if.h vnode_if.h
+
+.include <bsd.kmod.mk>
diff --git a/sys/modules/mem/Makefile b/sys/modules/mem/Makefile
new file mode 100644
index 0000000..d1529a5
--- /dev/null
+++ b/sys/modules/mem/Makefile
@@ -0,0 +1,10 @@
+# $FreeBSD$
+
+.PATH: ${.CURDIR}/../../dev/mem
+.PATH: ${.CURDIR}/../../${MACHINE_ARCH}/${MACHINE_ARCH}
+
+KMOD=	mem
+SRCS=	memdev.c mem.c
+SRCS+=	bus_if.h device_if.h vnode_if.h
+
+.include <bsd.kmod.mk>
diff --git a/sys/pc98/conf/GENERIC b/sys/pc98/conf/GENERIC
index 6498139..23db02c 100644
--- a/sys/pc98/conf/GENERIC
+++ b/sys/pc98/conf/GENERIC
@@ -216,8 +216,10 @@ device		wi		# WaveLAN/Intersil/Symbol 802.11 wireless NICs.
 #device		wl		# Older non 802.11 Wavelan wireless NIC.
 
 # Pseudo devices.
-device		random		# Entropy device
 device		loop		# Network loopback
+device		mem		# Memory and kernel memory devices
+device		null		# Null and zero devices
+device		random		# Entropy device
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
 device		ppp		# Kernel PPP
diff --git a/sys/powerpc/conf/GENERIC b/sys/powerpc/conf/GENERIC
index 0da074d..c0cebc3 100644
--- a/sys/powerpc/conf/GENERIC
+++ b/sys/powerpc/conf/GENERIC
@@ -102,8 +102,10 @@ device 		dc		# DEC/Intel 21143 and various workalikes
 device 		fxp		# Intel EtherExpress PRO/100B (82557, 82558)
 
 # Pseudo devices.
-device		random		# Entropy device
 device		loop		# Network loopback
+device		mem		# Memory and kernel memory devices
+device		null		# Null and zero devices
+device		random		# Entropy device
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
 device		ppp		# Kernel PPP
diff --git a/sys/sparc64/conf/GENERIC b/sys/sparc64/conf/GENERIC
index d5fe010..dab8d2e 100644
--- a/sys/sparc64/conf/GENERIC
+++ b/sys/sparc64/conf/GENERIC
@@ -165,8 +165,10 @@ device		rl		# RealTek 8129/8139
 device		xl		# 3Com 3c90x (``Boomerang'', ``Cyclone'')
 
 # Pseudo devices.
-device		random		# Entropy device
 device		loop		# Network loopback
+device		mem		# Memory and kernel memory devices
+device		null		# Null and zero devices
+device		random		# Entropy device
 device		ether		# Ethernet support
 device		sl		# Kernel SLIP
 device		ppp		# Kernel PPP
diff --git a/sys/sparc64/include/memdev.h b/sys/sparc64/include/memdev.h
new file mode 100644
index 0000000..671a6b4
--- /dev/null
+++ b/sys/sparc64/include/memdev.h
@@ -0,0 +1,38 @@
+/*-
+ * Copyright (c) 2004 Mark R V Murray
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer
+ *    in this position and unchanged.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#define CDEV_MAJOR	2
+#define	CDEV_MINOR_MEM	0
+#define	CDEV_MINOR_KMEM	1
+
+d_open_t	memopen;
+d_read_t	memrw;
+#define		memioctl	(d_ioctl_t *)NULL
+#define		memmmap		(d_mmap_t *)NULL
+
+void		dev_mem_md_init(void);
diff --git a/sys/sparc64/sparc64/mem.c b/sys/sparc64/sparc64/mem.c
index d7a1818..66bbea9 100644
--- a/sys/sparc64/sparc64/mem.c
+++ b/sys/sparc64/sparc64/mem.c
@@ -35,10 +35,11 @@
  *	from: Utah $Hdr: mem.c 1.13 89/10/08$
  *	from: @(#)mem.c	7.2 (Berkeley) 5/9/91
  *	from: FreeBSD: src/sys/i386/i386/mem.c,v 1.94 2001/09/26
- *
- * $FreeBSD$
  */
 
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
 /*
  * Memory special file
  *
@@ -52,9 +53,10 @@
 #include <sys/fcntl.h>
 #include <sys/kernel.h>
 #include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/memrange.h>
 #include <sys/module.h>
 #include <sys/mutex.h>
-#include <sys/module.h>
 #include <sys/proc.h>
 #include <sys/signalvar.h>
 #include <sys/systm.h>
@@ -73,54 +75,13 @@
 #include <machine/tlb.h>
 #include <machine/upa.h>
 
-static struct cdev *memdev, *kmemdev;
-
-static	d_open_t	mmopen;
-static	d_close_t	mmclose;
-static	d_read_t	mmrw;
-
-#define CDEV_MAJOR 2
-static struct cdevsw mem_cdevsw = {
-	.d_version =	D_VERSION,
-	.d_open =	mmopen,
-	.d_close =	mmclose,
-	.d_read =	mmrw,
-	.d_write =	mmrw,
-	.d_name =	"mem",
-	.d_maj =	CDEV_MAJOR,
-	.d_flags =	D_MEM | D_NEEDGIANT,
-};
-
-static int
-mmclose(struct cdev *dev, int flags, int fmt, struct thread *td)
-{
+#include <machine/memdev.h>
 
-	return (0);
-}
+struct mem_range_softc mem_range_softc;
 
-static int
-mmopen(struct cdev *dev, int flags, int fmt, struct thread *td)
-{
-	int error;
-
-	switch (minor(dev)) {
-	case 0:
-	case 1:
-		if (flags & FWRITE) {
-			error = securelevel_gt(td->td_ucred, 0);
-			if (error != 0)
-				return (error);
-		}
-		break;
-	default:
-		return (ENXIO);
-	}
-	return (0);
-}
-
-/*ARGSUSED*/
-static int
-mmrw(struct cdev *dev, struct uio *uio, int flags)
+/* ARGSUSED */
+int
+memrw(struct cdev *dev, struct uio *uio, int flags)
 {
 	struct iovec *iov;
 	vm_offset_t eva;
@@ -147,12 +108,10 @@ mmrw(struct cdev *dev, struct uio *uio, int flags)
 			uio->uio_iov++;
 			uio->uio_iovcnt--;
 			if (uio->uio_iovcnt < 0)
-				panic("mmrw");
+				panic("memrw");
 			continue;
 		}
-		switch (minor(dev)) {
-		case 0:
-			/* mem (physical memory) */
+		if (minor(dev) == CDEV_MINOR_MEM) {
 			pa = uio->uio_offset & ~PAGE_MASK;
 			if (!is_physical_memory(pa)) {
 				error = EFAULT;
@@ -193,8 +152,8 @@ mmrw(struct cdev *dev, struct uio *uio, int flags)
 				    uio);
 			}
 			break;
-		case 1:
-			/* kmem (kernel memory) */
+		}
+		else if (minor(dev) == CDEV_MINOR_KMEM) {
 			va = trunc_page(uio->uio_offset);
 			eva = round_page(uio->uio_offset + iov->iov_len);
 
@@ -215,40 +174,15 @@ mmrw(struct cdev *dev, struct uio *uio, int flags)
 
 			error = uiomove((void *)va, iov->iov_len, uio);
 			break;
-		default:
-			return (ENODEV);
 		}
+		/* else panic! */
 	}
 	if (ova != 0)
 		kmem_free_wakeup(kernel_map, ova, PAGE_SIZE * DCACHE_COLORS);
 	return (error);
 }
 
-static int
-mem_modevent(module_t mod, int type, void *data)
+void
+dev_mem_md_init(void)
 {
-	switch(type) {
-	case MOD_LOAD:
-		if (bootverbose)
-			printf("mem: <memory & I/O>\n");
-
-		memdev = make_dev(&mem_cdevsw, 0, UID_ROOT, GID_KMEM,
-			0640, "mem");
-		kmemdev = make_dev(&mem_cdevsw, 1, UID_ROOT, GID_KMEM,
-			0640, "kmem");
-		return 0;
-
-	case MOD_UNLOAD:
-		destroy_dev(memdev);
-		destroy_dev(kmemdev);
-		return 0;
-
-	case MOD_SHUTDOWN:
-		return 0;
-
-	default:
-		return EOPNOTSUPP;
-	}
 }
-
-DEV_MODULE(mem, mem_modevent, NULL);