From b513c26294324c9c81aa94c85d2e8dc2d3ffd009 Mon Sep 17 00:00:00 2001
From: David Greenman <dg@FreeBSD.org>
Date: Mon, 22 Nov 1993 09:46:45 +0000
Subject: [PATCH] patches from Julian Elischer - Added support for mmapping
 /dev/mem

---
 sys/amd64/amd64/mem.c | 28 +++++++++++++++++++++++++++-
 sys/i386/i386/conf.c  |  6 +++---
 sys/i386/i386/mem.c   | 28 +++++++++++++++++++++++++++-
 3 files changed, 57 insertions(+), 5 deletions(-)

diff --git a/sys/amd64/amd64/mem.c b/sys/amd64/amd64/mem.c
index 51c62cacf1e2..0caf00c07f5c 100644
--- a/sys/amd64/amd64/mem.c
+++ b/sys/amd64/amd64/mem.c
@@ -38,7 +38,7 @@
  *
  *	from: Utah $Hdr: mem.c 1.13 89/10/08$
  *	from: @(#)mem.c	7.2 (Berkeley) 5/9/91
- *	$Id$
+ *	$Id: mem.c,v 1.3 1993/10/16 14:15:06 rgrimes Exp $
  */
 
 /*
@@ -228,3 +228,29 @@ mmrw(dev, uio, flags)
 		free(zbuf, M_TEMP);
 	return (error);
 }
+
+
+
+
+/*******************************************************\
+* allow user processes to MMAP some memory sections	*
+* instead of going through read/write			*
+\*******************************************************/
+int memmmap(dev_t dev, int offset, int nprot)
+{
+	switch (minor(dev))
+	{
+
+/* minor device 0 is physical memory */
+	case 0:
+        	return i386_btop(offset);
+
+/* minor device 1 is kernel memory */
+	case 1:
+        	return i386_btop(vtophys(offset));
+
+	default:
+		return -1;
+	}
+}
+
diff --git a/sys/i386/i386/conf.c b/sys/i386/i386/conf.c
index ae333fd5869f..41e9aeb66bdd 100644
--- a/sys/i386/i386/conf.c
+++ b/sys/i386/i386/conf.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	from: @(#)conf.c	5.8 (Berkeley) 5/12/91
- *	$Id: conf.c,v 1.14 1993/11/03 18:07:32 nate Exp $
+ *	$Id: conf.c,v 1.15 1993/11/18 05:01:51 rgrimes Exp $
  */
 
 #include "param.h"
@@ -188,7 +188,7 @@ extern	struct tty pccons;
 
 int	cttyopen(), cttyread(), cttywrite(), cttyioctl(), cttyselect();
 
-int 	mmopen(), mmclose(), mmrw();
+int 	mmopen(), mmclose(), mmrw(), memmmap();
 #define	mmselect	seltrue
 
 #include "pty.h"
@@ -393,7 +393,7 @@ struct cdevsw	cdevsw[] =
 	  cttyselect,	enodev,		NULL },
 	{ mmopen,	mmclose,	mmrw,		mmrw,		/*2*/
 	  enodev,	nullop,		nullop,		NULL,	/* memory */
-	  mmselect,	enodev,		NULL },
+	  mmselect,	memmmap,	NULL },
 	{ wdopen,	wdclose,	rawread,	rawwrite,	/*3*/
 	  wdioctl,	enodev,		nullop,		NULL,	/* wd */
 	  seltrue,	enodev,		wdstrategy },
diff --git a/sys/i386/i386/mem.c b/sys/i386/i386/mem.c
index 51c62cacf1e2..0caf00c07f5c 100644
--- a/sys/i386/i386/mem.c
+++ b/sys/i386/i386/mem.c
@@ -38,7 +38,7 @@
  *
  *	from: Utah $Hdr: mem.c 1.13 89/10/08$
  *	from: @(#)mem.c	7.2 (Berkeley) 5/9/91
- *	$Id$
+ *	$Id: mem.c,v 1.3 1993/10/16 14:15:06 rgrimes Exp $
  */
 
 /*
@@ -228,3 +228,29 @@ mmrw(dev, uio, flags)
 		free(zbuf, M_TEMP);
 	return (error);
 }
+
+
+
+
+/*******************************************************\
+* allow user processes to MMAP some memory sections	*
+* instead of going through read/write			*
+\*******************************************************/
+int memmmap(dev_t dev, int offset, int nprot)
+{
+	switch (minor(dev))
+	{
+
+/* minor device 0 is physical memory */
+	case 0:
+        	return i386_btop(offset);
+
+/* minor device 1 is kernel memory */
+	case 1:
+        	return i386_btop(vtophys(offset));
+
+	default:
+		return -1;
+	}
+}
+