From f85b90abd2073c769ea4f9e49ab618428c60ddfc Mon Sep 17 00:00:00 2001
From: okuji <okuji@localhost>
Date: Sat, 27 May 2000 07:40:53 +0000
Subject: [PATCH] add diskless support.

---
 AUTHORS            |   2 +
 ChangeLog          |  51 ++++++++
 NEWS               |   4 +
 THANKS             |   1 +
 configure          | 182 ++++++++++++++++-------------
 configure.in       |  11 ++
 stage2/Makefile.am |  56 ++++++++-
 stage2/Makefile.in | 281 ++++++++++++++++++++++++++++++++++++++++++---
 stage2/asm.S       |   8 +-
 stage2/common.c    |  41 +++++--
 stage2/nbi.h       |  27 +++++
 stage2/nbloader.S  |  49 ++++++++
 stage2/pxeloader.S |  36 ++++++
 13 files changed, 643 insertions(+), 106 deletions(-)
 create mode 100644 stage2/nbi.h
 create mode 100644 stage2/nbloader.S
 create mode 100644 stage2/pxeloader.S

diff --git a/AUTHORS b/AUTHORS
index 31d663a15..300832d0c 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -28,3 +28,5 @@ Per Lundberg added graphics support to the Multiboot Specification.
 
 Jochen Hoenicke rewrote stage2/fsys_fat.c and wrote
 stage2/fsys_reiserfs.c.
+
+Christoph Plattner added support for Net Boot Image Proposal.
diff --git a/ChangeLog b/ChangeLog
index e2f8be269..5d5b96c79 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,54 @@
+2000-05-27  OKUJI Yoshinori  <okuji@gnu.org>
+
+	Add diskless support, mostly based on patches by Christoph
+	Plattner <Christoph.Plattner@dot.at>, but also based on a patch
+	by Chip Salzenberg <chip@valinux.com> for PXE. Of course, I've
+	modified both the patches thoroughly to adapt them to my
+	preference.
+
+	* configure.in (--enable-diskless): New option. Set a
+	conditional DISKLESS_SUPPORT.
+	* stage2/Makefile.am (noinst_HEADERS): Added nbi.h.
+	(EXTRA_PROGRAMS): New variable.
+	(pkgdata_DATA) [DISKLESS_SUPPORT]: Added
+	nbgrub and pxegrub.
+	(noinst_DATA) [DISKLESS_SUPPORT]: Added nbloader, pxeloader and
+	diskless.
+	(noinst_PROGRAMS) [DISKLESS_SUPPORT]: Added nbloader.exec,
+	pxeloader.exec and diskless.exec.
+	(PXELOADER_LINK): New variable.
+	(BUILT_SOURCES) [DISKLESS_SUPPORT]: Added diskless_size.h.
+	(diskless_exec_SOURCES): New variable.
+	(diskless_exec_CFLAGS): Likewise.
+	(diskless_exec_LDFLAGS): Likewise.
+	(diskless_exec_LDADD): Likewise.
+	(diskless_size.h): New target.
+	(nbloader_exec_SOURCES): New variable.
+	(nbloader_exec_CFLAGS): Likewise.
+	(nbloader_exec_LDFLAGS): Likewise.
+	(nbloader_exec-nbloader.o): New dependency.
+	(nbgrub): New target.
+	(pxeloader_exec_SOURCES): new variable.
+	(pxeloader_exec_CFLAGS): Likewise.
+	(pxeloader_exec_LDFLAGS): Likewise.
+	(pxegrub): New target.
+	* stage2/asm.S (install_partition): Set to 0xFFFFFF instead of
+	0x020000. What was the benefit from the previous setting?
+	(codestart) [SUPPORT_DISKLESS]: Don't move %dl to BOOT_DRIVE.
+	(boot_drive) [SUPPORT_DISKLESS]: Set to NETWORK_DRIVE instead of
+	zero.
+	* stage2/common.c: Include <shared.h> instead of "shared.h",
+	just for a cosmetic reason.
+	[SUPPORT_DISKLESS]: Include etherboot.h.
+	[SUPPORT_DISKLESS] (setup_diskless_environment): New internal
+	function.
+	(init_bios_info) [SUPPORT_DISKLESS]: Call
+	setup_diskless_environment after the memory initialization is
+	finished. Return if fails.
+	* stage2/nbloader.S: New file.
+	* stage2/pxeloader.S: Likewise.
+	* stage2/nbi.h: Likewise.
+	
 2000-05-25  OKUJI Yoshinori  <okuji@gnu.org>
 
 	* netboot/fsys_tftp.c (buf_fill): Warn when amazing things
diff --git a/NEWS b/NEWS
index 561b0d0c9..14165a938 100644
--- a/NEWS
+++ b/NEWS
@@ -31,6 +31,10 @@ New in 0.5.95 - XXXX-XX-XX:
   enters a correct password.
 * Recognize the Linux extended partition type.
 * Pass a correct memory size to Linux and *BSD.
+* Diskless support is added. Now configure accepts --enable-diskless,
+  and "make" will produce two additional images, ``nbgrub'' for Net Boot
+  Image Proposal and ``pxegrub'' for Preboot Execution Environment. See
+  the documentation, for more details.
 
 New in 0.5.94 - 2000-03-06:
 * Stage 1 supports both the LBA mode and the CHS mode.
diff --git a/THANKS b/THANKS
index c7cd75535..bc165335e 100644
--- a/THANKS
+++ b/THANKS
@@ -12,6 +12,7 @@ Bradford Hovinen <hovinen@redrose.net>
 Brian Brunswick <brian@skarpsey.demon.co.uk>
 Bryan Ford <baford@cs.utah.edu>
 Chip Salzenberg <chip@valinux.com>
+Christoph Plattner <Christoph.Plattner@dot.at>
 Dan J. Walters <djw@cs.utexas.edu>
 Edmund GRIMLEY EVANS <edmundo@rano.demon.co.uk>
 Edward Killips <ekillips@triton.net>
diff --git a/configure b/configure
index fb7034a83..e100f65fd 100644
--- a/configure
+++ b/configure
@@ -109,6 +109,8 @@ ac_help="$ac_help
                           set the default memory location for WD/SMC"
 ac_help="$ac_help
   --enable-cs-scan=LIST   probe for CS89x0 base address using LIST"
+ac_help="$ac_help
+  --enable-diskless       enable diskless support"
 
 # Initialize some variables set by options.
 # The variables have the same names as the options, with
@@ -650,7 +652,7 @@ ac_configure=$ac_aux_dir/configure # This should be Cygnus configure.
 # SVR4 /usr/ucb/install, which tries to use the nonexistent group "staff"
 # ./install, which can be erroneously created by make from ./install.sh.
 echo $ac_n "checking for a BSD compatible install""... $ac_c" 1>&6
-echo "configure:654: checking for a BSD compatible install" >&5
+echo "configure:656: checking for a BSD compatible install" >&5
 if test -z "$INSTALL"; then
 if eval "test \"`echo '$''{'ac_cv_path_install'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -703,7 +705,7 @@ test -z "$INSTALL_SCRIPT" && INSTALL_SCRIPT='${INSTALL_PROGRAM}'
 test -z "$INSTALL_DATA" && INSTALL_DATA='${INSTALL} -m 644'
 
 echo $ac_n "checking whether build environment is sane""... $ac_c" 1>&6
-echo "configure:707: checking whether build environment is sane" >&5
+echo "configure:709: checking whether build environment is sane" >&5
 # Just in case
 sleep 1
 echo timestamp > conftestfile
@@ -775,7 +777,7 @@ do
 # Extract the first word of "$ac_prog", so it can be a program name with args.
 set dummy $ac_prog; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:779: checking for $ac_word" >&5
+echo "configure:781: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_AWK'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -805,7 +807,7 @@ test -n "$AWK" && break
 done
 
 echo $ac_n "checking whether ${MAKE-make} sets \${MAKE}""... $ac_c" 1>&6
-echo "configure:809: checking whether ${MAKE-make} sets \${MAKE}" >&5
+echo "configure:811: checking whether ${MAKE-make} sets \${MAKE}" >&5
 set dummy ${MAKE-make}; ac_make=`echo "$2" | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_prog_make_${ac_make}_set'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -931,7 +933,7 @@ else { echo "configure: error: can not run $ac_config_sub" 1>&2; exit 1; }
 fi
 
 echo $ac_n "checking host system type""... $ac_c" 1>&6
-echo "configure:935: checking host system type" >&5
+echo "configure:937: checking host system type" >&5
 
 host_alias=$host
 case "$host_alias" in
@@ -965,7 +967,7 @@ esac
 #
 
 echo $ac_n "checking whether to enable maintainer-specific portions of Makefiles""... $ac_c" 1>&6
-echo "configure:969: checking whether to enable maintainer-specific portions of Makefiles" >&5
+echo "configure:971: checking whether to enable maintainer-specific portions of Makefiles" >&5
     # Check whether --enable-maintainer-mode or --disable-maintainer-mode was given.
 if test "${enable_maintainer_mode+set}" = set; then
   enableval="$enable_maintainer_mode"
@@ -991,7 +993,7 @@ if test "x$enable_maintainer_mode" = xyes; then
   # Extract the first word of "perl", so it can be a program name with args.
 set dummy perl; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:995: checking for $ac_word" >&5
+echo "configure:997: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_PERL'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1038,7 +1040,7 @@ fi
 #
 
 echo $ac_n "checking build system type""... $ac_c" 1>&6
-echo "configure:1042: checking build system type" >&5
+echo "configure:1044: checking build system type" >&5
 
 build_alias=$build
 case "$build_alias" in
@@ -1064,7 +1066,7 @@ fi
 # Extract the first word of "${ac_tool_prefix}gcc", so it can be a program name with args.
 set dummy ${ac_tool_prefix}gcc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1068: checking for $ac_word" >&5
+echo "configure:1070: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1096,7 +1098,7 @@ fi
 # Extract the first word of "gcc", so it can be a program name with args.
 set dummy gcc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1100: checking for $ac_word" >&5
+echo "configure:1102: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1126,7 +1128,7 @@ if test -z "$CC"; then
   # Extract the first word of "cc", so it can be a program name with args.
 set dummy cc; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1130: checking for $ac_word" >&5
+echo "configure:1132: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1177,7 +1179,7 @@ fi
       # Extract the first word of "cl", so it can be a program name with args.
 set dummy cl; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1181: checking for $ac_word" >&5
+echo "configure:1183: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_CC'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1209,7 +1211,7 @@ fi
 fi
 
 echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works""... $ac_c" 1>&6
-echo "configure:1213: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
+echo "configure:1215: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) works" >&5
 
 ac_ext=c
 # CFLAGS is not in ac_cpp because -g, -O, etc. are not valid cpp options.
@@ -1220,12 +1222,12 @@ cross_compiling=$ac_cv_prog_cc_cross
 
 cat > conftest.$ac_ext << EOF
 
-#line 1224 "configure"
+#line 1226 "configure"
 #include "confdefs.h"
 
 main(){return(0);}
 EOF
-if { (eval echo configure:1229: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1231: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   ac_cv_prog_cc_works=yes
   # If we can't run a trivial program, we are probably using a cross compiler.
   if (./conftest; exit) 2>/dev/null; then
@@ -1251,12 +1253,12 @@ if test $ac_cv_prog_cc_works = no; then
   { echo "configure: error: installation or configuration problem: C compiler cannot create executables." 1>&2; exit 1; }
 fi
 echo $ac_n "checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler""... $ac_c" 1>&6
-echo "configure:1255: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
+echo "configure:1257: checking whether the C compiler ($CC $CFLAGS $LDFLAGS) is a cross-compiler" >&5
 echo "$ac_t""$ac_cv_prog_cc_cross" 1>&6
 cross_compiling=$ac_cv_prog_cc_cross
 
 echo $ac_n "checking whether we are using GNU C""... $ac_c" 1>&6
-echo "configure:1260: checking whether we are using GNU C" >&5
+echo "configure:1262: checking whether we are using GNU C" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_gcc'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1265,7 +1267,7 @@ else
   yes;
 #endif
 EOF
-if { ac_try='${CC-cc} -E conftest.c'; { (eval echo configure:1269: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } | egrep yes >/dev/null 2>&1; then
+if { ac_try='${CC-cc} -E conftest.c'; { (eval echo configure:1271: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } | egrep yes >/dev/null 2>&1; then
   ac_cv_prog_gcc=yes
 else
   ac_cv_prog_gcc=no
@@ -1284,7 +1286,7 @@ ac_test_CFLAGS="${CFLAGS+set}"
 ac_save_CFLAGS="$CFLAGS"
 CFLAGS=
 echo $ac_n "checking whether ${CC-cc} accepts -g""... $ac_c" 1>&6
-echo "configure:1288: checking whether ${CC-cc} accepts -g" >&5
+echo "configure:1290: checking whether ${CC-cc} accepts -g" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_cc_g'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1317,7 +1319,7 @@ fi
 
 
 echo $ac_n "checking how to run the C preprocessor""... $ac_c" 1>&6
-echo "configure:1321: checking how to run the C preprocessor" >&5
+echo "configure:1323: checking how to run the C preprocessor" >&5
 # On Suns, sometimes $CPP names a directory.
 if test -n "$CPP" && test -d "$CPP"; then
   CPP=
@@ -1332,13 +1334,13 @@ else
   # On the NeXT, cc -E runs the code through the compiler's parser,
   # not just through cpp.
   cat > conftest.$ac_ext <<EOF
-#line 1336 "configure"
+#line 1338 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1342: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1344: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1349,13 +1351,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -E -traditional-cpp"
   cat > conftest.$ac_ext <<EOF
-#line 1353 "configure"
+#line 1355 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1359: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1361: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1366,13 +1368,13 @@ else
   rm -rf conftest*
   CPP="${CC-cc} -nologo -E"
   cat > conftest.$ac_ext <<EOF
-#line 1370 "configure"
+#line 1372 "configure"
 #include "confdefs.h"
 #include <assert.h>
 Syntax Error
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:1376: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:1378: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   :
@@ -1405,7 +1407,7 @@ echo "$ac_t""$CPP" 1>&6
 depcc="$CC"
 depcpp="$CPP"
 echo $ac_n "checking dependency style of $depcc""... $ac_c" 1>&6
-echo "configure:1409: checking dependency style of $depcc" >&5
+echo "configure:1411: checking dependency style of $depcc" >&5
 if eval "test \"`echo '$''{'am_cv_CC_dependencies_compiler_type'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1461,7 +1463,7 @@ if test "x$with_binutils" != x; then
   # Extract the first word of "ranlib", so it can be a program name with args.
 set dummy ranlib; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1465: checking for $ac_word" >&5
+echo "configure:1467: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_RANLIB'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1498,7 +1500,7 @@ else
   # Extract the first word of "ranlib", so it can be a program name with args.
 set dummy ranlib; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1502: checking for $ac_word" >&5
+echo "configure:1504: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_RANLIB'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1538,7 +1540,7 @@ if test "x$ac_cv_prog_gcc" = xyes; then
     STAGE1_CFLAGS="-O2"
     GRUB_CFLAGS="-O2"
     echo $ac_n "checking whether optimization for size works""... $ac_c" 1>&6
-echo "configure:1542: checking whether optimization for size works" >&5
+echo "configure:1544: checking whether optimization for size works" >&5
 if eval "test \"`echo '$''{'size_flag'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1546,14 +1548,14 @@ else
       saved_CFLAGS=$CFLAGS
       CFLAGS="-Os -g"
       cat > conftest.$ac_ext <<EOF
-#line 1550 "configure"
+#line 1552 "configure"
 #include "confdefs.h"
 
 int main() {
 
 ; return 0; }
 EOF
-if { (eval echo configure:1557: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
+if { (eval echo configure:1559: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; }; then
   rm -rf conftest*
   size_flag=yes
 else
@@ -1587,7 +1589,7 @@ if test "x$with_binutils" != x; then
   # Extract the first word of "objcopy", so it can be a program name with args.
 set dummy objcopy; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1591: checking for $ac_word" >&5
+echo "configure:1593: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_path_OBJCOPY'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1623,7 +1625,7 @@ else
   # Extract the first word of "${ac_tool_prefix}objcopy", so it can be a program name with args.
 set dummy ${ac_tool_prefix}objcopy; ac_word=$2
 echo $ac_n "checking for $ac_word""... $ac_c" 1>&6
-echo "configure:1627: checking for $ac_word" >&5
+echo "configure:1629: checking for $ac_word" >&5
 if eval "test \"`echo '$''{'ac_cv_prog_OBJCOPY'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1657,7 +1659,7 @@ fi
 # Defined in acinclude.m4.
 
 echo $ac_n "checking if C symbols get an underscore after compilation""... $ac_c" 1>&6
-echo "configure:1661: checking if C symbols get an underscore after compilation" >&5
+echo "configure:1663: checking if C symbols get an underscore after compilation" >&5
 if eval "test \"`echo '$''{'grub_cv_asm_uscore'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1670,7 +1672,7 @@ func (int *list)
 }
 EOF
 
-if { ac_try='${CC-cc} ${CFLAGS} -S conftest.c'; { (eval echo configure:1674: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.s; then
+if { ac_try='${CC-cc} ${CFLAGS} -S conftest.c'; { (eval echo configure:1676: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.s; then
   true
 else
   { echo "configure: error: ${CC-cc} failed to produce assembly code" 1>&2; exit 1; }
@@ -1696,7 +1698,7 @@ fi
 echo "$ac_t""$grub_cv_asm_uscore" 1>&6
 
 echo $ac_n "checking whether ${OBJCOPY} works for absolute addresses""... $ac_c" 1>&6
-echo "configure:1700: checking whether ${OBJCOPY} works for absolute addresses" >&5
+echo "configure:1702: checking whether ${OBJCOPY} works for absolute addresses" >&5
 if eval "test \"`echo '$''{'grub_cv_prog_objcopy_absolute'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1708,21 +1710,21 @@ cmain (void)
 }
 EOF
 
-if { (eval echo configure:1712: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; } && test -s conftest.o; then :
+if { (eval echo configure:1714: \"$ac_compile\") 1>&5; (eval $ac_compile) 2>&5; } && test -s conftest.o; then :
 else
   { echo "configure: error: ${CC-cc} cannot compile C source code" 1>&2; exit 1; }
 fi
 grub_cv_prog_objcopy_absolute=yes
 for link_addr in 2000 8000 7C00; do
-  if { ac_try='${CC-cc} ${CFLAGS} -nostdlib -Wl,-N -Wl,-Ttext -Wl,$link_addr conftest.o -o conftest.exec'; { (eval echo configure:1718: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then :
+  if { ac_try='${CC-cc} ${CFLAGS} -nostdlib -Wl,-N -Wl,-Ttext -Wl,$link_addr conftest.o -o conftest.exec'; { (eval echo configure:1720: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then :
   else
     { echo "configure: error: ${CC-cc} cannot link at address $link_addr" 1>&2; exit 1; }
   fi
-  if { ac_try='${OBJCOPY-objcopy} -O binary conftest.exec conftest'; { (eval echo configure:1722: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then :
+  if { ac_try='${OBJCOPY-objcopy} -O binary conftest.exec conftest'; { (eval echo configure:1724: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then :
   else
     { echo "configure: error: ${OBJCOPY-objcopy} cannot create binary files" 1>&2; exit 1; }
   fi
-  if test ! -f conftest.old || { ac_try='cmp -s conftest.old conftest'; { (eval echo configure:1726: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then
+  if test ! -f conftest.old || { ac_try='cmp -s conftest.old conftest'; { (eval echo configure:1728: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; }; then
     mv -f conftest conftest.old
   else
     grub_cv_prog_objcopy_absolute=no
@@ -1739,7 +1741,7 @@ fi
 
 
 echo $ac_n "checking whether addr32 must be in the same line as the instruction""... $ac_c" 1>&6
-echo "configure:1743: checking whether addr32 must be in the same line as the instruction" >&5
+echo "configure:1745: checking whether addr32 must be in the same line as the instruction" >&5
 if eval "test \"`echo '$''{'grub_cv_asm_prefix_requirement'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1748,7 +1750,7 @@ else
 l1:	addr32	movb	%al, l1
 EOF
 
-if { ac_try='${CC-cc} ${CFLAGS} -c conftest.s'; { (eval echo configure:1752: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.o; then
+if { ac_try='${CC-cc} ${CFLAGS} -c conftest.s'; { (eval echo configure:1754: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.o; then
   grub_cv_asm_prefix_requirement=yes
 else
   grub_cv_asm_prefix_requirement=no
@@ -1780,7 +1782,7 @@ echo "$ac_t""$grub_cv_asm_prefix_requirement" 1>&6
 
 
 echo $ac_n "checking for .code16 addr32 assembler support""... $ac_c" 1>&6
-echo "configure:1784: checking for .code16 addr32 assembler support" >&5
+echo "configure:1786: checking for .code16 addr32 assembler support" >&5
 if eval "test \"`echo '$''{'grub_cv_asm_addr32'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
@@ -1795,7 +1797,7 @@ else
   sed -e s/@ADDR32@/addr32\;/ < conftest.s.in > conftest.s
 fi
 
-if { ac_try='${CC-cc} ${CFLAGS} -c conftest.s'; { (eval echo configure:1799: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.o; then
+if { ac_try='${CC-cc} ${CFLAGS} -c conftest.s'; { (eval echo configure:1801: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }; } && test -s conftest.o; then
   grub_cv_asm_addr32=yes
 else
   grub_cv_asm_addr32=no
@@ -1812,19 +1814,19 @@ fi
 
 
 echo $ac_n "checking if start is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1816: checking if start is defined by the compiler" >&5
+echo "configure:1818: checking if start is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_start_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1821 "configure"
+#line 1823 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl start")
 ; return 0; }
 EOF
-if { (eval echo configure:1828: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1830: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_start_symbol=yes
 else
@@ -1848,19 +1850,19 @@ echo "$ac_t""$grub_cv_check_start_symbol" 1>&6
 
 
 echo $ac_n "checking if _start is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1852: checking if _start is defined by the compiler" >&5
+echo "configure:1854: checking if _start is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_uscore_start_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1857 "configure"
+#line 1859 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl _start")
 ; return 0; }
 EOF
-if { (eval echo configure:1864: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1866: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_uscore_start_symbol=yes
 else
@@ -1889,19 +1891,19 @@ fi
 
 
 echo $ac_n "checking if __bss_start is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1893: checking if __bss_start is defined by the compiler" >&5
+echo "configure:1895: checking if __bss_start is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_uscore_uscore_bss_start_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1898 "configure"
+#line 1900 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl __bss_start")
 ; return 0; }
 EOF
-if { (eval echo configure:1905: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1907: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_uscore_uscore_bss_start_symbol=yes
 else
@@ -1925,19 +1927,19 @@ echo "$ac_t""$grub_cv_check_uscore_uscore_bss_start_symbol" 1>&6
 
 
 echo $ac_n "checking if _edata is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1929: checking if _edata is defined by the compiler" >&5
+echo "configure:1931: checking if _edata is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_uscore_edata_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1934 "configure"
+#line 1936 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl _edata")
 ; return 0; }
 EOF
-if { (eval echo configure:1941: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1943: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_uscore_edata_symbol=yes
 else
@@ -1961,19 +1963,19 @@ echo "$ac_t""$grub_cv_check_uscore_edata_symbol" 1>&6
 
 
 echo $ac_n "checking if edata is defined by the compiler""... $ac_c" 1>&6
-echo "configure:1965: checking if edata is defined by the compiler" >&5
+echo "configure:1967: checking if edata is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_edata_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 1970 "configure"
+#line 1972 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl edata")
 ; return 0; }
 EOF
-if { (eval echo configure:1977: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:1979: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_edata_symbol=yes
 else
@@ -2003,19 +2005,19 @@ fi
 
 
 echo $ac_n "checking if end is defined by the compiler""... $ac_c" 1>&6
-echo "configure:2007: checking if end is defined by the compiler" >&5
+echo "configure:2009: checking if end is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_end_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2012 "configure"
+#line 2014 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl end")
 ; return 0; }
 EOF
-if { (eval echo configure:2019: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2021: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_end_symbol=yes
 else
@@ -2039,19 +2041,19 @@ echo "$ac_t""$grub_cv_check_end_symbol" 1>&6
 
 
 echo $ac_n "checking if _end is defined by the compiler""... $ac_c" 1>&6
-echo "configure:2043: checking if _end is defined by the compiler" >&5
+echo "configure:2045: checking if _end is defined by the compiler" >&5
 if eval "test \"`echo '$''{'grub_cv_check_uscore_end_symbol'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2048 "configure"
+#line 2050 "configure"
 #include "confdefs.h"
 
 int main() {
 asm ("incl _end")
 ; return 0; }
 EOF
-if { (eval echo configure:2055: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2057: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   grub_cv_check_uscore_end_symbol=yes
 else
@@ -2089,7 +2091,7 @@ fi
 # Get the filename or the whole disk and open it.
 # Known to work on NetBSD.
 echo $ac_n "checking for opendisk in -lutil""... $ac_c" 1>&6
-echo "configure:2093: checking for opendisk in -lutil" >&5
+echo "configure:2095: checking for opendisk in -lutil" >&5
 ac_lib_var=`echo util'_'opendisk | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2097,7 +2099,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lutil  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2101 "configure"
+#line 2103 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2108,7 +2110,7 @@ int main() {
 opendisk()
 ; return 0; }
 EOF
-if { (eval echo configure:2112: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2114: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2136,7 +2138,7 @@ fi
 # Unless the user specify --without-curses, check for curses.
 if test "x$with_curses" != "xno"; then
   echo $ac_n "checking for wgetch in -lncurses""... $ac_c" 1>&6
-echo "configure:2140: checking for wgetch in -lncurses" >&5
+echo "configure:2142: checking for wgetch in -lncurses" >&5
 ac_lib_var=`echo ncurses'_'wgetch | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2144,7 +2146,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lncurses  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2148 "configure"
+#line 2150 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2155,7 +2157,7 @@ int main() {
 wgetch()
 ; return 0; }
 EOF
-if { (eval echo configure:2159: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2161: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2178,7 +2180,7 @@ EOF
 else
   echo "$ac_t""no" 1>&6
 echo $ac_n "checking for wgetch in -lcurses""... $ac_c" 1>&6
-echo "configure:2182: checking for wgetch in -lcurses" >&5
+echo "configure:2184: checking for wgetch in -lcurses" >&5
 ac_lib_var=`echo curses'_'wgetch | sed 'y%./+-%__p_%'`
 if eval "test \"`echo '$''{'ac_cv_lib_$ac_lib_var'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
@@ -2186,7 +2188,7 @@ else
   ac_save_LIBS="$LIBS"
 LIBS="-lcurses  $LIBS"
 cat > conftest.$ac_ext <<EOF
-#line 2190 "configure"
+#line 2192 "configure"
 #include "confdefs.h"
 /* Override any gcc2 internal prototype to avoid an error.  */
 /* We use char because int might match the return type of a gcc2
@@ -2197,7 +2199,7 @@ int main() {
 wgetch()
 ; return 0; }
 EOF
-if { (eval echo configure:2201: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
+if { (eval echo configure:2203: \"$ac_link\") 1>&5; (eval $ac_link) 2>&5; } && test -s conftest${ac_exeext}; then
   rm -rf conftest*
   eval "ac_cv_lib_$ac_lib_var=yes"
 else
@@ -2232,17 +2234,17 @@ for ac_hdr in string.h strings.h ncurses/curses.h ncurses.h curses.h
 do
 ac_safe=`echo "$ac_hdr" | sed 'y%./+-%__p_%'`
 echo $ac_n "checking for $ac_hdr""... $ac_c" 1>&6
-echo "configure:2236: checking for $ac_hdr" >&5
+echo "configure:2238: checking for $ac_hdr" >&5
 if eval "test \"`echo '$''{'ac_cv_header_$ac_safe'+set}'`\" = set"; then
   echo $ac_n "(cached) $ac_c" 1>&6
 else
   cat > conftest.$ac_ext <<EOF
-#line 2241 "configure"
+#line 2243 "configure"
 #include "confdefs.h"
 #include <$ac_hdr>
 EOF
 ac_try="$ac_cpp conftest.$ac_ext >/dev/null 2>conftest.out"
-{ (eval echo configure:2246: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
+{ (eval echo configure:2248: \"$ac_try\") 1>&5; (eval $ac_try) 2>&5; }
 ac_err=`grep -v '^ *+' conftest.out | grep -v "^conftest.${ac_ext}\$"`
 if test -z "$ac_err"; then
   rm -rf conftest*
@@ -2731,6 +2733,28 @@ if test "${enable_cs_scan+set}" = set; then
 fi
 
 
+# Check whether --enable-diskless or --disable-diskless was given.
+if test "${enable_diskless+set}" = set; then
+  enableval="$enable_diskless"
+  :
+fi
+
+
+
+if test "x$enable_diskless" = xyes; then
+  DISKLESS_SUPPORT_TRUE=
+  DISKLESS_SUPPORT_FALSE='#'
+else
+  DISKLESS_SUPPORT_TRUE='#'
+  DISKLESS_SUPPORT_FALSE=
+fi
+
+# Sanity check.
+if test "x$enable_diskless" = xyes; then
+  if test "x$NET_CFLAGS" = x; then
+    { echo "configure: error: You must enable at least one network driver" 1>&2; exit 1; }
+  fi
+fi
 
 
 
@@ -2915,6 +2939,8 @@ s%@OBJCOPY@%$OBJCOPY%g
 s%@GRUB_LIBS@%$GRUB_LIBS%g
 s%@NETBOOT_SUPPORT_TRUE@%$NETBOOT_SUPPORT_TRUE%g
 s%@NETBOOT_SUPPORT_FALSE@%$NETBOOT_SUPPORT_FALSE%g
+s%@DISKLESS_SUPPORT_TRUE@%$DISKLESS_SUPPORT_TRUE%g
+s%@DISKLESS_SUPPORT_FALSE@%$DISKLESS_SUPPORT_FALSE%g
 s%@FSYS_CFLAGS@%$FSYS_CFLAGS%g
 s%@NET_CFLAGS@%$NET_CFLAGS%g
 s%@NET_EXTRAFLAGS@%$NET_EXTRAFLAGS%g
diff --git a/configure.in b/configure.in
index 93091191a..fe09bbae1 100644
--- a/configure.in
+++ b/configure.in
@@ -464,6 +464,17 @@ AC_ARG_ENABLE(cs-scan,
   [  --enable-cs-scan=LIST   probe for CS89x0 base address using LIST],
   [NET_EXTRAFLAGS="$NET_EXTRAFLAGS -DCS_SCAN=$enable_cs_scan"])
 
+dnl Diskless
+AC_ARG_ENABLE(diskless,
+  [  --enable-diskless       enable diskless support])
+AM_CONDITIONAL(DISKLESS_SUPPORT, test "x$enable_diskless" = xyes)
+
+# Sanity check.
+if test "x$enable_diskless" = xyes; then
+  if test "x$NET_CFLAGS" = x; then
+    AC_MSG_ERROR([You must enable at least one network driver])
+  fi
+fi
 
 dnl Now substitute the variables.
 AC_SUBST(FSYS_CFLAGS)
diff --git a/stage2/Makefile.am b/stage2/Makefile.am
index 09dc403f3..cfa69a75e 100644
--- a/stage2/Makefile.am
+++ b/stage2/Makefile.am
@@ -5,7 +5,7 @@ noinst_SCRIPTS = $(TESTS)
 # For dist target.
 noinst_HEADERS = apic.h defs.h dir.h disk_inode.h disk_inode_ffs.h \
         fat.h filesys.h freebsd.h fs.h i386-elf.h imgact_aout.h \
-        mb_header.h mb_info.h pc_slice.h shared.h smp-imps.h
+        mb_header.h mb_info.h pc_slice.h shared.h smp-imps.h nbi.h
 EXTRA_DIST = $(noinst_SCRIPTS)
 
 # For <stage1.h>.
@@ -22,16 +22,30 @@ libgrub_a_CFLAGS = $(GRUB_CFLAGS) -DGRUB_UTIL=1 -DFSYS_EXT2FS=1 \
 
 # Stage 2 and Stage 1.5's.
 pkgdatadir = $(datadir)/$(PACKAGE)/$(host_cpu)-$(host_vendor)
+
+EXTRA_PROGRAMS = nbloader.exec pxeloader.exec diskless.exec
+
+if DISKLESS_SUPPORT
+pkgdata_DATA = stage2 e2fs_stage1_5 fat_stage1_5 ffs_stage1_5 \
+	minix_stage1_5 reiserfs_stage1_5 nbgrub pxegrub
+noinst_DATA = pre_stage2 start nbloader pxeloader diskless
+noinst_PROGRAMS = pre_stage2.exec start.exec e2fs_stage1_5.exec \
+	fat_stage1_5.exec ffs_stage1_5.exec minix_stage1_5.exec \
+	reiserfs_stage1_5.exec nbloader.exec pxeloader.exec \
+	diskless.exec
+else
 pkgdata_DATA = stage2 e2fs_stage1_5 fat_stage1_5 ffs_stage1_5 \
 	minix_stage1_5 reiserfs_stage1_5
 noinst_DATA = pre_stage2 start
 noinst_PROGRAMS = pre_stage2.exec start.exec e2fs_stage1_5.exec \
 	fat_stage1_5.exec ffs_stage1_5.exec minix_stage1_5.exec \
 	reiserfs_stage1_5.exec
+endif
 MOSTLYCLEANFILES = $(noinst_PROGRAMS)
 
 PRE_STAGE2_LINK = -nostdlib -Wl,-N -Wl,-Ttext -Wl,8200
 START_LINK = -nostdlib -Wl,-N -Wl,-Ttext -Wl,8000
+PXELOADER_LINK = -nostdlib -Wl,-N -Wl,-Ttext -Wl,7C00
 if NETBOOT_SUPPORT
 STAGE2_COMPILE = $(STAGE2_CFLAGS) -fno-builtin -nostdinc \
 	-I$(top_srcdir)/netboot -DSUPPORT_NETBOOT=1
@@ -54,7 +68,12 @@ if NETBOOT_SUPPORT
 pre_stage2_exec_LDADD = ../netboot/libdrivers.a
 endif
 
+if DISKLESS_SUPPORT
+BUILT_SOURCES = stage2_size.h diskless_size.h
+else
 BUILT_SOURCES = stage2_size.h
+endif
+
 CLEANFILES = $(pkgdata_DATA) $(noinst_DATA) $(BUILT_SOURCES)
 
 stage2_size.h: pre_stage2
@@ -112,6 +131,41 @@ reiserfs_stage1_5_exec_CFLAGS = $(STAGE1_5_COMPILE) -DFSYS_REISERFS=1 \
 	-DNO_BLOCK_FILES=1
 reiserfs_stage1_5_exec_LDFLAGS = $(STAGE1_5_LINK)
 
+# For diskless target.
+diskless_exec_SOURCES = $(pre_stage2_exec_SOURCES)
+diskless_exec_CFLAGS = $(STAGE2_COMPILE) $(FSYS_CFLAGS) \
+	-DSUPPORT_DISKLESS=1
+diskless_exec_LDFLAGS = $(PRE_STAGE2_LINK)
+diskless_exec_LDADD = ../netboot/libdrivers.a
+
+diskless_size.h: diskless
+	-rm -f $@
+	set dummy `ls -l $^`; \
+	echo "#define DISKLESS_SIZE $$6" > $@
+
+# For nbloader target.
+nbloader_exec_SOURCES = nbloader.S
+nbloader_exec_CFLAGS = $(STAGE2_COMPILE)
+nbloader_exec_LDFLAGS = $(START_LINK)
+
+# XXX: See the comment for start_exec-start.o.
+nbloader_exec-nbloader.o: diskless_size.h
+
+# For nbgrub target.
+nbgrub: nbloader diskless
+	-rm -f $@
+	cat $^ > $@
+
+# For pxeloader target.
+pxeloader_exec_SOURCES = pxeloader.S
+pxeloader_exec_CFLAGS = $(STAGE2_COMPILE)
+pxeloader_exec_LDFLAGS = $(PXELOADER_LINK)
+
+# For pxegrub target.
+pxegrub: pxeloader diskless
+	-rm -f $@
+	cat $^ > $@
+
 # General rule for making a raw binary.
 %: %.exec
 	$(OBJCOPY) -O binary $< $@
diff --git a/stage2/Makefile.in b/stage2/Makefile.in
index e2c3e843b..39f5dcdd7 100644
--- a/stage2/Makefile.in
+++ b/stage2/Makefile.in
@@ -93,7 +93,7 @@ noinst_SCRIPTS = $(TESTS)
 # For dist target.
 noinst_HEADERS = apic.h defs.h dir.h disk_inode.h disk_inode_ffs.h \
         fat.h filesys.h freebsd.h fs.h i386-elf.h imgact_aout.h \
-        mb_header.h mb_info.h pc_slice.h shared.h smp-imps.h
+        mb_header.h mb_info.h pc_slice.h shared.h smp-imps.h nbi.h
 
 EXTRA_DIST = $(noinst_SCRIPTS)
 
@@ -113,18 +113,26 @@ libgrub_a_CFLAGS = $(GRUB_CFLAGS) -DGRUB_UTIL=1 -DFSYS_EXT2FS=1 \
 
 # Stage 2 and Stage 1.5's.
 pkgdatadir = $(datadir)/$(PACKAGE)/$(host_cpu)-$(host_vendor)
-pkgdata_DATA = stage2 e2fs_stage1_5 fat_stage1_5 ffs_stage1_5 \
-	minix_stage1_5 reiserfs_stage1_5
-
-noinst_DATA = pre_stage2 start
-noinst_PROGRAMS = pre_stage2.exec start.exec e2fs_stage1_5.exec \
-	fat_stage1_5.exec ffs_stage1_5.exec minix_stage1_5.exec \
-	reiserfs_stage1_5.exec
 
+EXTRA_PROGRAMS = nbloader.exec pxeloader.exec diskless.exec
+@DISKLESS_SUPPORT_TRUE@pkgdata_DATA = @DISKLESS_SUPPORT_TRUE@stage2 e2fs_stage1_5 fat_stage1_5 ffs_stage1_5 \
+@DISKLESS_SUPPORT_TRUE@	minix_stage1_5 reiserfs_stage1_5 nbgrub pxegrub
+@DISKLESS_SUPPORT_FALSE@pkgdata_DATA = @DISKLESS_SUPPORT_FALSE@stage2 e2fs_stage1_5 fat_stage1_5 ffs_stage1_5 \
+@DISKLESS_SUPPORT_FALSE@	minix_stage1_5 reiserfs_stage1_5
+@DISKLESS_SUPPORT_TRUE@noinst_DATA = @DISKLESS_SUPPORT_TRUE@pre_stage2 start nbloader pxeloader diskless
+@DISKLESS_SUPPORT_FALSE@noinst_DATA = @DISKLESS_SUPPORT_FALSE@pre_stage2 start
+@DISKLESS_SUPPORT_TRUE@noinst_PROGRAMS = @DISKLESS_SUPPORT_TRUE@pre_stage2.exec start.exec e2fs_stage1_5.exec \
+@DISKLESS_SUPPORT_TRUE@	fat_stage1_5.exec ffs_stage1_5.exec minix_stage1_5.exec \
+@DISKLESS_SUPPORT_TRUE@	reiserfs_stage1_5.exec nbloader.exec pxeloader.exec \
+@DISKLESS_SUPPORT_TRUE@	diskless.exec
+@DISKLESS_SUPPORT_FALSE@noinst_PROGRAMS = @DISKLESS_SUPPORT_FALSE@pre_stage2.exec start.exec e2fs_stage1_5.exec \
+@DISKLESS_SUPPORT_FALSE@	fat_stage1_5.exec ffs_stage1_5.exec minix_stage1_5.exec \
+@DISKLESS_SUPPORT_FALSE@	reiserfs_stage1_5.exec
 MOSTLYCLEANFILES = $(noinst_PROGRAMS)
 
 PRE_STAGE2_LINK = -nostdlib -Wl,-N -Wl,-Ttext -Wl,8200
 START_LINK = -nostdlib -Wl,-N -Wl,-Ttext -Wl,8000
+PXELOADER_LINK = -nostdlib -Wl,-N -Wl,-Ttext -Wl,7C00
 @NETBOOT_SUPPORT_TRUE@STAGE2_COMPILE = @NETBOOT_SUPPORT_TRUE@$(STAGE2_CFLAGS) -fno-builtin -nostdinc \
 @NETBOOT_SUPPORT_TRUE@	-I$(top_srcdir)/netboot -DSUPPORT_NETBOOT=1
 @NETBOOT_SUPPORT_FALSE@STAGE2_COMPILE = @NETBOOT_SUPPORT_FALSE@$(STAGE2_CFLAGS) -fno-builtin -nostdinc
@@ -142,8 +150,9 @@ pre_stage2_exec_CFLAGS = $(STAGE2_COMPILE) $(FSYS_CFLAGS)
 pre_stage2_exec_LDFLAGS = $(PRE_STAGE2_LINK)
 
 @NETBOOT_SUPPORT_TRUE@pre_stage2_exec_LDADD = @NETBOOT_SUPPORT_TRUE@../netboot/libdrivers.a
+@DISKLESS_SUPPORT_TRUE@BUILT_SOURCES = @DISKLESS_SUPPORT_TRUE@stage2_size.h diskless_size.h
+@DISKLESS_SUPPORT_FALSE@BUILT_SOURCES = @DISKLESS_SUPPORT_FALSE@stage2_size.h
 
-BUILT_SOURCES = stage2_size.h
 CLEANFILES = $(pkgdata_DATA) $(noinst_DATA) $(BUILT_SOURCES)
 
 start_exec_SOURCES = start.S
@@ -195,6 +204,24 @@ reiserfs_stage1_5_exec_CFLAGS = $(STAGE1_5_COMPILE) -DFSYS_REISERFS=1 \
 	-DNO_BLOCK_FILES=1
 
 reiserfs_stage1_5_exec_LDFLAGS = $(STAGE1_5_LINK)
+
+# For diskless target.
+diskless_exec_SOURCES = $(pre_stage2_exec_SOURCES)
+diskless_exec_CFLAGS = $(STAGE2_COMPILE) $(FSYS_CFLAGS) \
+	-DSUPPORT_DISKLESS=1
+
+diskless_exec_LDFLAGS = $(PRE_STAGE2_LINK)
+diskless_exec_LDADD = ../netboot/libdrivers.a
+
+# For nbloader target.
+nbloader_exec_SOURCES = nbloader.S
+nbloader_exec_CFLAGS = $(STAGE2_COMPILE)
+nbloader_exec_LDFLAGS = $(START_LINK)
+
+# For pxeloader target.
+pxeloader_exec_SOURCES = pxeloader.S
+pxeloader_exec_CFLAGS = $(STAGE2_COMPILE)
+pxeloader_exec_LDFLAGS = $(PXELOADER_LINK)
 subdir = stage2
 mkinstalldirs = $(SHELL) $(top_srcdir)/mkinstalldirs
 CONFIG_HEADER = ../config.h
@@ -217,6 +244,15 @@ libgrub_a_OBJECTS =  $(am_libgrub_a_OBJECTS)
 AR = ar
 PROGRAMS =  $(noinst_PROGRAMS)
 
+am_diskless_exec_OBJECTS =  diskless_exec-asm.o diskless_exec-bios.o \
+diskless_exec-boot.o diskless_exec-builtins.o diskless_exec-common.o \
+diskless_exec-char_io.o diskless_exec-cmdline.o diskless_exec-disk_io.o \
+diskless_exec-gunzip.o diskless_exec-fsys_ext2fs.o \
+diskless_exec-fsys_fat.o diskless_exec-fsys_ffs.o \
+diskless_exec-fsys_minix.o diskless_exec-fsys_reiserfs.o \
+diskless_exec-smp-imps.o diskless_exec-stage2.o
+diskless_exec_OBJECTS =  $(am_diskless_exec_OBJECTS)
+diskless_exec_DEPENDENCIES =  ../netboot/libdrivers.a
 am_e2fs_stage1_5_exec_OBJECTS =  e2fs_stage1_5_exec-start.o \
 e2fs_stage1_5_exec-asm.o e2fs_stage1_5_exec-common.o \
 e2fs_stage1_5_exec-char_io.o e2fs_stage1_5_exec-disk_io.o \
@@ -249,6 +285,10 @@ minix_stage1_5_exec-bios.o
 minix_stage1_5_exec_OBJECTS =  $(am_minix_stage1_5_exec_OBJECTS)
 minix_stage1_5_exec_LDADD = $(LDADD)
 minix_stage1_5_exec_DEPENDENCIES = 
+am_nbloader_exec_OBJECTS =  nbloader_exec-nbloader.o
+nbloader_exec_OBJECTS =  $(am_nbloader_exec_OBJECTS)
+nbloader_exec_LDADD = $(LDADD)
+nbloader_exec_DEPENDENCIES = 
 am_pre_stage2_exec_OBJECTS =  pre_stage2_exec-asm.o \
 pre_stage2_exec-bios.o pre_stage2_exec-boot.o \
 pre_stage2_exec-builtins.o pre_stage2_exec-common.o \
@@ -261,6 +301,10 @@ pre_stage2_exec-stage2.o
 pre_stage2_exec_OBJECTS =  $(am_pre_stage2_exec_OBJECTS)
 @NETBOOT_SUPPORT_TRUE@pre_stage2_exec_DEPENDENCIES =  \
 @NETBOOT_SUPPORT_TRUE@../netboot/libdrivers.a
+am_pxeloader_exec_OBJECTS =  pxeloader_exec-pxeloader.o
+pxeloader_exec_OBJECTS =  $(am_pxeloader_exec_OBJECTS)
+pxeloader_exec_LDADD = $(LDADD)
+pxeloader_exec_DEPENDENCIES = 
 am_reiserfs_stage1_5_exec_OBJECTS =  reiserfs_stage1_5_exec-start.o \
 reiserfs_stage1_5_exec-asm.o reiserfs_stage1_5_exec-common.o \
 reiserfs_stage1_5_exec-char_io.o reiserfs_stage1_5_exec-disk_io.o \
@@ -279,16 +323,28 @@ COMPILE = $(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CFLAGS) $(CF
 CFLAGS = @CFLAGS@
 CCLD = $(CC)
 LINK = $(CCLD) $(AM_CFLAGS) $(CFLAGS) $(AM_LDFLAGS) $(LDFLAGS) -o $@
-DIST_SOURCES =  $(libgrub_a_SOURCES) $(e2fs_stage1_5_exec_SOURCES) \
-$(fat_stage1_5_exec_SOURCES) $(ffs_stage1_5_exec_SOURCES) \
-$(minix_stage1_5_exec_SOURCES) $(pre_stage2_exec_SOURCES) \
-$(reiserfs_stage1_5_exec_SOURCES) $(start_exec_SOURCES)
+DIST_SOURCES =  $(libgrub_a_SOURCES) $(diskless_exec_SOURCES) \
+$(e2fs_stage1_5_exec_SOURCES) $(fat_stage1_5_exec_SOURCES) \
+$(ffs_stage1_5_exec_SOURCES) $(minix_stage1_5_exec_SOURCES) \
+$(nbloader_exec_SOURCES) $(pre_stage2_exec_SOURCES) \
+$(pxeloader_exec_SOURCES) $(reiserfs_stage1_5_exec_SOURCES) \
+$(start_exec_SOURCES)
 DATA =  $(noinst_DATA) $(pkgdata_DATA)
 
 HEADERS =  $(noinst_HEADERS)
 
 depcomp = $(SHELL) $(top_srcdir)/depcomp
-DEP_FILES =  @AMDEP@ $(DEPDIR)/e2fs_stage1_5_exec-asm.Po \
+DEP_FILES =  @AMDEP@ $(DEPDIR)/diskless_exec-asm.Po \
+$(DEPDIR)/diskless_exec-bios.Po $(DEPDIR)/diskless_exec-boot.Po \
+$(DEPDIR)/diskless_exec-builtins.Po $(DEPDIR)/diskless_exec-char_io.Po \
+$(DEPDIR)/diskless_exec-cmdline.Po $(DEPDIR)/diskless_exec-common.Po \
+$(DEPDIR)/diskless_exec-disk_io.Po \
+$(DEPDIR)/diskless_exec-fsys_ext2fs.Po \
+$(DEPDIR)/diskless_exec-fsys_fat.Po $(DEPDIR)/diskless_exec-fsys_ffs.Po \
+$(DEPDIR)/diskless_exec-fsys_minix.Po \
+$(DEPDIR)/diskless_exec-fsys_reiserfs.Po \
+$(DEPDIR)/diskless_exec-gunzip.Po $(DEPDIR)/diskless_exec-smp-imps.Po \
+$(DEPDIR)/diskless_exec-stage2.Po $(DEPDIR)/e2fs_stage1_5_exec-asm.Po \
 $(DEPDIR)/e2fs_stage1_5_exec-bios.Po \
 $(DEPDIR)/e2fs_stage1_5_exec-char_io.Po \
 $(DEPDIR)/e2fs_stage1_5_exec-common.Po \
@@ -323,7 +379,8 @@ $(DEPDIR)/minix_stage1_5_exec-common.Po \
 $(DEPDIR)/minix_stage1_5_exec-disk_io.Po \
 $(DEPDIR)/minix_stage1_5_exec-fsys_minix.Po \
 $(DEPDIR)/minix_stage1_5_exec-stage1_5.Po \
-$(DEPDIR)/minix_stage1_5_exec-start.Po $(DEPDIR)/pre_stage2_exec-asm.Po \
+$(DEPDIR)/minix_stage1_5_exec-start.Po \
+$(DEPDIR)/nbloader_exec-nbloader.Po $(DEPDIR)/pre_stage2_exec-asm.Po \
 $(DEPDIR)/pre_stage2_exec-bios.Po $(DEPDIR)/pre_stage2_exec-boot.Po \
 $(DEPDIR)/pre_stage2_exec-builtins.Po \
 $(DEPDIR)/pre_stage2_exec-char_io.Po \
@@ -338,6 +395,7 @@ $(DEPDIR)/pre_stage2_exec-fsys_reiserfs.Po \
 $(DEPDIR)/pre_stage2_exec-gunzip.Po \
 $(DEPDIR)/pre_stage2_exec-smp-imps.Po \
 $(DEPDIR)/pre_stage2_exec-stage2.Po \
+$(DEPDIR)/pxeloader_exec-pxeloader.Po \
 $(DEPDIR)/reiserfs_stage1_5_exec-asm.Po \
 $(DEPDIR)/reiserfs_stage1_5_exec-bios.Po \
 $(DEPDIR)/reiserfs_stage1_5_exec-char_io.Po \
@@ -352,8 +410,8 @@ DIST_COMMON =  $(noinst_HEADERS) Makefile.am Makefile.in compile
 DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST)
 
 GZIP_ENV = --best
-SOURCES = $(libgrub_a_SOURCES) $(e2fs_stage1_5_exec_SOURCES) $(fat_stage1_5_exec_SOURCES) $(ffs_stage1_5_exec_SOURCES) $(minix_stage1_5_exec_SOURCES) $(pre_stage2_exec_SOURCES) $(reiserfs_stage1_5_exec_SOURCES) $(start_exec_SOURCES)
-OBJECTS = $(am_libgrub_a_OBJECTS) $(am_e2fs_stage1_5_exec_OBJECTS) $(am_fat_stage1_5_exec_OBJECTS) $(am_ffs_stage1_5_exec_OBJECTS) $(am_minix_stage1_5_exec_OBJECTS) $(am_pre_stage2_exec_OBJECTS) $(am_reiserfs_stage1_5_exec_OBJECTS) $(am_start_exec_OBJECTS)
+SOURCES = $(libgrub_a_SOURCES) $(diskless_exec_SOURCES) $(e2fs_stage1_5_exec_SOURCES) $(fat_stage1_5_exec_SOURCES) $(ffs_stage1_5_exec_SOURCES) $(minix_stage1_5_exec_SOURCES) $(nbloader_exec_SOURCES) $(pre_stage2_exec_SOURCES) $(pxeloader_exec_SOURCES) $(reiserfs_stage1_5_exec_SOURCES) $(start_exec_SOURCES)
+OBJECTS = $(am_libgrub_a_OBJECTS) $(am_diskless_exec_OBJECTS) $(am_e2fs_stage1_5_exec_OBJECTS) $(am_fat_stage1_5_exec_OBJECTS) $(am_ffs_stage1_5_exec_OBJECTS) $(am_minix_stage1_5_exec_OBJECTS) $(am_nbloader_exec_OBJECTS) $(am_pre_stage2_exec_OBJECTS) $(am_pxeloader_exec_OBJECTS) $(am_reiserfs_stage1_5_exec_OBJECTS) $(am_start_exec_OBJECTS)
 
 all: all-redirect
 .SUFFIXES:
@@ -411,6 +469,27 @@ clean-noinstPROGRAMS:
 distclean-noinstPROGRAMS:
 
 maintainer-clean-noinstPROGRAMS:
+diskless_exec-asm.o: asm.S
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-asm.o `test -f asm.S || echo '$(srcdir)/'`asm.S
+diskless_exec-bios.o: bios.c
+diskless_exec-boot.o: boot.c
+diskless_exec-builtins.o: builtins.c
+diskless_exec-common.o: common.c
+diskless_exec-char_io.o: char_io.c
+diskless_exec-cmdline.o: cmdline.c
+diskless_exec-disk_io.o: disk_io.c
+diskless_exec-gunzip.o: gunzip.c
+diskless_exec-fsys_ext2fs.o: fsys_ext2fs.c
+diskless_exec-fsys_fat.o: fsys_fat.c
+diskless_exec-fsys_ffs.o: fsys_ffs.c
+diskless_exec-fsys_minix.o: fsys_minix.c
+diskless_exec-fsys_reiserfs.o: fsys_reiserfs.c
+diskless_exec-smp-imps.o: smp-imps.c
+diskless_exec-stage2.o: stage2.c
+
+diskless.exec: $(diskless_exec_OBJECTS) $(diskless_exec_DEPENDENCIES)
+	@rm -f diskless.exec
+	$(LINK) $(diskless_exec_LDFLAGS) $(diskless_exec_OBJECTS) $(diskless_exec_LDADD) $(LIBS)
 e2fs_stage1_5_exec-start.o: start.S
 	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(e2fs_stage1_5_exec_CFLAGS) $(CFLAGS) -c -o e2fs_stage1_5_exec-start.o `test -f start.S || echo '$(srcdir)/'`start.S
 e2fs_stage1_5_exec-asm.o: asm.S
@@ -467,6 +546,12 @@ minix_stage1_5_exec-bios.o: bios.c
 minix_stage1_5.exec: $(minix_stage1_5_exec_OBJECTS) $(minix_stage1_5_exec_DEPENDENCIES)
 	@rm -f minix_stage1_5.exec
 	$(LINK) $(minix_stage1_5_exec_LDFLAGS) $(minix_stage1_5_exec_OBJECTS) $(minix_stage1_5_exec_LDADD) $(LIBS)
+nbloader_exec-nbloader.o: nbloader.S
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(nbloader_exec_CFLAGS) $(CFLAGS) -c -o nbloader_exec-nbloader.o `test -f nbloader.S || echo '$(srcdir)/'`nbloader.S
+
+nbloader.exec: $(nbloader_exec_OBJECTS) $(nbloader_exec_DEPENDENCIES)
+	@rm -f nbloader.exec
+	$(LINK) $(nbloader_exec_LDFLAGS) $(nbloader_exec_OBJECTS) $(nbloader_exec_LDADD) $(LIBS)
 pre_stage2_exec-asm.o: asm.S
 	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(pre_stage2_exec_CFLAGS) $(CFLAGS) -c -o pre_stage2_exec-asm.o `test -f asm.S || echo '$(srcdir)/'`asm.S
 pre_stage2_exec-bios.o: bios.c
@@ -488,6 +573,12 @@ pre_stage2_exec-stage2.o: stage2.c
 pre_stage2.exec: $(pre_stage2_exec_OBJECTS) $(pre_stage2_exec_DEPENDENCIES)
 	@rm -f pre_stage2.exec
 	$(LINK) $(pre_stage2_exec_LDFLAGS) $(pre_stage2_exec_OBJECTS) $(pre_stage2_exec_LDADD) $(LIBS)
+pxeloader_exec-pxeloader.o: pxeloader.S
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(pxeloader_exec_CFLAGS) $(CFLAGS) -c -o pxeloader_exec-pxeloader.o `test -f pxeloader.S || echo '$(srcdir)/'`pxeloader.S
+
+pxeloader.exec: $(pxeloader_exec_OBJECTS) $(pxeloader_exec_DEPENDENCIES)
+	@rm -f pxeloader.exec
+	$(LINK) $(pxeloader_exec_LDFLAGS) $(pxeloader_exec_OBJECTS) $(pxeloader_exec_LDADD) $(LIBS)
 reiserfs_stage1_5_exec-start.o: start.S
 	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(reiserfs_stage1_5_exec_CFLAGS) $(CFLAGS) -c -o reiserfs_stage1_5_exec-start.o `test -f start.S || echo '$(srcdir)/'`start.S
 reiserfs_stage1_5_exec-asm.o: asm.S
@@ -562,6 +653,22 @@ distclean-tags:
 
 maintainer-clean-tags:
 
+@AMDEP@include $(DEPDIR)/diskless_exec-asm.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-bios.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-boot.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-builtins.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-char_io.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-cmdline.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-common.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-disk_io.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-fsys_ext2fs.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-fsys_fat.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-fsys_ffs.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-fsys_minix.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-fsys_reiserfs.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-gunzip.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-smp-imps.Po
+@AMDEP@include $(DEPDIR)/diskless_exec-stage2.Po
 @AMDEP@include $(DEPDIR)/e2fs_stage1_5_exec-asm.Po
 @AMDEP@include $(DEPDIR)/e2fs_stage1_5_exec-bios.Po
 @AMDEP@include $(DEPDIR)/e2fs_stage1_5_exec-char_io.Po
@@ -607,6 +714,7 @@ maintainer-clean-tags:
 @AMDEP@include $(DEPDIR)/minix_stage1_5_exec-fsys_minix.Po
 @AMDEP@include $(DEPDIR)/minix_stage1_5_exec-stage1_5.Po
 @AMDEP@include $(DEPDIR)/minix_stage1_5_exec-start.Po
+@AMDEP@include $(DEPDIR)/nbloader_exec-nbloader.Po
 @AMDEP@include $(DEPDIR)/pre_stage2_exec-asm.Po
 @AMDEP@include $(DEPDIR)/pre_stage2_exec-bios.Po
 @AMDEP@include $(DEPDIR)/pre_stage2_exec-boot.Po
@@ -623,6 +731,7 @@ maintainer-clean-tags:
 @AMDEP@include $(DEPDIR)/pre_stage2_exec-gunzip.Po
 @AMDEP@include $(DEPDIR)/pre_stage2_exec-smp-imps.Po
 @AMDEP@include $(DEPDIR)/pre_stage2_exec-stage2.Po
+@AMDEP@include $(DEPDIR)/pxeloader_exec-pxeloader.Po
 @AMDEP@include $(DEPDIR)/reiserfs_stage1_5_exec-asm.Po
 @AMDEP@include $(DEPDIR)/reiserfs_stage1_5_exec-bios.Po
 @AMDEP@include $(DEPDIR)/reiserfs_stage1_5_exec-char_io.Po
@@ -757,6 +866,126 @@ libgrub_a-stage2.o: stage2.c
 
 @AMDEP@CCDEPMODE = @CCDEPMODE@
 
+diskless_exec-bios.o: bios.c
+@AMDEP@	source='bios.c' object='diskless_exec-bios.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-bios.Po' tmpdepfile='$(DEPDIR)/diskless_exec-bios.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-bios.o `test -f bios.c || echo '$(srcdir)/'`bios.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-boot.o: boot.c
+@AMDEP@	source='boot.c' object='diskless_exec-boot.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-boot.Po' tmpdepfile='$(DEPDIR)/diskless_exec-boot.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-boot.o `test -f boot.c || echo '$(srcdir)/'`boot.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-builtins.o: builtins.c
+@AMDEP@	source='builtins.c' object='diskless_exec-builtins.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-builtins.Po' tmpdepfile='$(DEPDIR)/diskless_exec-builtins.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-builtins.o `test -f builtins.c || echo '$(srcdir)/'`builtins.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-common.o: common.c
+@AMDEP@	source='common.c' object='diskless_exec-common.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-common.Po' tmpdepfile='$(DEPDIR)/diskless_exec-common.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-common.o `test -f common.c || echo '$(srcdir)/'`common.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-char_io.o: char_io.c
+@AMDEP@	source='char_io.c' object='diskless_exec-char_io.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-char_io.Po' tmpdepfile='$(DEPDIR)/diskless_exec-char_io.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-char_io.o `test -f char_io.c || echo '$(srcdir)/'`char_io.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-cmdline.o: cmdline.c
+@AMDEP@	source='cmdline.c' object='diskless_exec-cmdline.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-cmdline.Po' tmpdepfile='$(DEPDIR)/diskless_exec-cmdline.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-cmdline.o `test -f cmdline.c || echo '$(srcdir)/'`cmdline.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-disk_io.o: disk_io.c
+@AMDEP@	source='disk_io.c' object='diskless_exec-disk_io.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-disk_io.Po' tmpdepfile='$(DEPDIR)/diskless_exec-disk_io.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-disk_io.o `test -f disk_io.c || echo '$(srcdir)/'`disk_io.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-gunzip.o: gunzip.c
+@AMDEP@	source='gunzip.c' object='diskless_exec-gunzip.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-gunzip.Po' tmpdepfile='$(DEPDIR)/diskless_exec-gunzip.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-gunzip.o `test -f gunzip.c || echo '$(srcdir)/'`gunzip.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-fsys_ext2fs.o: fsys_ext2fs.c
+@AMDEP@	source='fsys_ext2fs.c' object='diskless_exec-fsys_ext2fs.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-fsys_ext2fs.Po' tmpdepfile='$(DEPDIR)/diskless_exec-fsys_ext2fs.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-fsys_ext2fs.o `test -f fsys_ext2fs.c || echo '$(srcdir)/'`fsys_ext2fs.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-fsys_fat.o: fsys_fat.c
+@AMDEP@	source='fsys_fat.c' object='diskless_exec-fsys_fat.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-fsys_fat.Po' tmpdepfile='$(DEPDIR)/diskless_exec-fsys_fat.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-fsys_fat.o `test -f fsys_fat.c || echo '$(srcdir)/'`fsys_fat.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-fsys_ffs.o: fsys_ffs.c
+@AMDEP@	source='fsys_ffs.c' object='diskless_exec-fsys_ffs.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-fsys_ffs.Po' tmpdepfile='$(DEPDIR)/diskless_exec-fsys_ffs.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-fsys_ffs.o `test -f fsys_ffs.c || echo '$(srcdir)/'`fsys_ffs.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-fsys_minix.o: fsys_minix.c
+@AMDEP@	source='fsys_minix.c' object='diskless_exec-fsys_minix.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-fsys_minix.Po' tmpdepfile='$(DEPDIR)/diskless_exec-fsys_minix.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-fsys_minix.o `test -f fsys_minix.c || echo '$(srcdir)/'`fsys_minix.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-fsys_reiserfs.o: fsys_reiserfs.c
+@AMDEP@	source='fsys_reiserfs.c' object='diskless_exec-fsys_reiserfs.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-fsys_reiserfs.Po' tmpdepfile='$(DEPDIR)/diskless_exec-fsys_reiserfs.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-fsys_reiserfs.o `test -f fsys_reiserfs.c || echo '$(srcdir)/'`fsys_reiserfs.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-smp-imps.o: smp-imps.c
+@AMDEP@	source='smp-imps.c' object='diskless_exec-smp-imps.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-smp-imps.Po' tmpdepfile='$(DEPDIR)/diskless_exec-smp-imps.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-smp-imps.o `test -f smp-imps.c || echo '$(srcdir)/'`smp-imps.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
+diskless_exec-stage2.o: stage2.c
+@AMDEP@	source='stage2.c' object='diskless_exec-stage2.o' libtool=no @AMDEPBACKSLASH@
+@AMDEP@	depfile='$(DEPDIR)/diskless_exec-stage2.Po' tmpdepfile='$(DEPDIR)/diskless_exec-stage2.TPo' @AMDEPBACKSLASH@
+@AMDEP@	$(CCDEPMODE) $(depcomp) @AMDEPBACKSLASH@
+	$(CC) $(DEFS) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(diskless_exec_CFLAGS) $(CFLAGS) -c -o diskless_exec-stage2.o `test -f stage2.c || echo '$(srcdir)/'`stage2.c
+
+@AMDEP@CCDEPMODE = @CCDEPMODE@
+
 e2fs_stage1_5_exec-common.o: common.c
 @AMDEP@	source='common.c' object='e2fs_stage1_5_exec-common.o' libtool=no @AMDEPBACKSLASH@
 @AMDEP@	depfile='$(DEPDIR)/e2fs_stage1_5_exec-common.Po' tmpdepfile='$(DEPDIR)/e2fs_stage1_5_exec-common.TPo' @AMDEPBACKSLASH@
@@ -1279,6 +1508,24 @@ stage2: pre_stage2 start
 	-rm -f stage2
 	cat start pre_stage2 > stage2
 
+diskless_size.h: diskless
+	-rm -f $@
+	set dummy `ls -l $^`; \
+	echo "#define DISKLESS_SIZE $$6" > $@
+
+# XXX: See the comment for start_exec-start.o.
+nbloader_exec-nbloader.o: diskless_size.h
+
+# For nbgrub target.
+nbgrub: nbloader diskless
+	-rm -f $@
+	cat $^ > $@
+
+# For pxegrub target.
+pxegrub: pxeloader diskless
+	-rm -f $@
+	cat $^ > $@
+
 # General rule for making a raw binary.
 %: %.exec
 	$(OBJCOPY) -O binary $< $@
diff --git a/stage2/asm.S b/stage2/asm.S
index 9d1e942e6..31f352f94 100644
--- a/stage2/asm.S
+++ b/stage2/asm.S
@@ -70,7 +70,7 @@ ENTRY(main)
 	. = EXT_C(main) + 0x8
 
 VARIABLE(install_partition)
-	.long	0x020000
+	.long	0xFFFFFF
 VARIABLE(stage2_id)
 	.byte	STAGE2_ID
 VARIABLE(force_lba)
@@ -107,8 +107,10 @@ codestart:
 
 	sti		/* we're safe again */
 
+#ifndef DISKLESS_SUPPORT
 	/* save boot drive reference */
 	ADDR32	movb	%dl, EXT_C(boot_drive)
+#endif
 
 	/* reset disk system (%ah = 0) */
 	int	$0x13
@@ -2071,7 +2073,11 @@ protstack:
 	.long	PROTSTACKINIT
 
 VARIABLE(boot_drive)
+#ifdef SUPPORT_DISKLESS
+	.long	NETWORK_DRIVE
+#else
 	.long	0
+#endif
 
 	/* an address can only be long-jumped to if it is in memory, this
 	   is used by multiple routines */
diff --git a/stage2/common.c b/stage2/common.c
index 1a39c4ad1..007d1989c 100644
--- a/stage2/common.c
+++ b/stage2/common.c
@@ -19,7 +19,11 @@
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#include "shared.h"
+#include <shared.h>
+
+#ifdef SUPPORT_DISKLESS
+# include <etherboot.h>
+#endif
 
 /*
  *  Shared BIOS/boot data.
@@ -125,6 +129,25 @@ mmap_avail_at (unsigned long bottom)
 }
 #endif /* ! STAGE1_5 */
 
+#ifdef SUPPORT_DISKLESS
+/* Set up the diskless environment so that GRUB can get a configuration
+   file from a network.  */
+static int
+setup_diskless_environment (void)
+{
+  /* For now, there is no difference between BOOTP and DHCP in GRUB.  */
+  if (! bootp ())
+    {
+      grub_printf ("BOOTP/DHCP fails.\n");
+      return 0;
+    }
+
+  /* This will be erased soon, though...  */
+  print_network_configuration ();
+  return 1;
+}
+#endif /* SUPPORT_DISKLESS */
+
 /* This queries for BIOS information.  */
 void
 init_bios_info (void)
@@ -240,16 +263,16 @@ init_bios_info (void)
 
 #endif /* STAGE1_5 */
 
-  /*
-   *  Set boot drive and partition.
-   */
-
+#ifdef SUPPORT_DISKLESS
+  /* If SUPPORT_DISKLESS is defined, initialize the network here.  */
+  if (! setup_diskless_environment ())
+    return;
+#endif
+  
+  /* Set boot drive and partition.  */
   saved_drive = boot_drive;
   saved_partition = install_partition;
 
-  /*
-   *  Start main routine here.
-   */
-
+  /* Start main routine here.  */
   cmain ();
 }
diff --git a/stage2/nbi.h b/stage2/nbi.h
new file mode 100644
index 000000000..eabe907bb
--- /dev/null
+++ b/stage2/nbi.h
@@ -0,0 +1,27 @@
+/* nbi.h - definitions for Net Boot Image */
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2000  Free Software Foundation, Inc.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef GRUB_NBI_HEADER
+#define GRUB_NBI_HEADER
+
+#define NBI_MAGIC	0x1B031336
+#define NBI_DEST_ADDR	0x8000
+
+#endif /* ! GRUB_NBI_HEADER */
diff --git a/stage2/nbloader.S b/stage2/nbloader.S
new file mode 100644
index 000000000..1095b926b
--- /dev/null
+++ b/stage2/nbloader.S
@@ -0,0 +1,49 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2000   Free Software Foundation, Inc.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <nbi.h>
+#include <diskless_size.h>
+			
+	.file	"nbloader.S"
+	.text
+
+	/* Just a dummy entry */
+.globl _start; _start:
+
+	/*
+	 * netboot image header
+	 */
+
+	.long	NBI_MAGIC
+	.long	0x00000004
+	/* load address of the first block  */
+	.word	NBI_DEST_ADDR
+	.word	0x0000
+	/* start addr of the code (stage 2) */
+	.word	NBI_DEST_ADDR + 0x0200
+	.word	0x0000
+
+	.long	0x04000004
+	.long	NBI_DEST_ADDR + 0x0200
+	.long	DISKLESS_SIZE + 0x200
+	.long	DISKLESS_SIZE + 0x200
+
+	/* This ensures that the length of this image will be 1 sector */
+	. = _start + 0x200 - 1
+	.byte	0
diff --git a/stage2/pxeloader.S b/stage2/pxeloader.S
new file mode 100644
index 000000000..80e95fe7e
--- /dev/null
+++ b/stage2/pxeloader.S
@@ -0,0 +1,36 @@
+/*
+ *  GRUB  --  GRand Unified Bootloader
+ *  Copyright (C) 2000   Free Software Foundation, Inc.
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+	.file	"pxeloader.S"
+	.text
+
+	/* Start with the prehistoric environment... */
+	.code16
+	
+	/* Let's go */
+.globl _start; _start:
+
+	/* Jump to the real world */
+	ljmp	$0, $0x8200
+
+	/* This region is a junk. Do you say that this is wasteful?
+	   But I like that the memory layout of the body is consistent
+	   among different stage2s rather than scamping just for 1.5KB. */
+	. = _start + 0x8200 - 0x7C00 - 1
+	.byte	0