diff --git a/arch/um/os-Linux/Makefile b/arch/um/os-Linux/Makefile
new file mode 100644
index 0000000..4ddf540
--- /dev/null
+++ b/arch/um/os-Linux/Makefile
@@ -0,0 +1,13 @@
+# 
+# Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
+# Licensed under the GPL
+#
+
+obj-y = elf_aux.o file.o process.o signal.o time.o tty.o user_syms.o drivers/ \
+	sys-$(SUBARCH)/
+
+USER_OBJS := elf_aux.o file.o process.o signal.o time.o tty.o
+
+CFLAGS_user_syms.o += -DSUBARCH_$(SUBARCH)
+
+include arch/um/scripts/Makefile.rules
diff --git a/arch/um/os-Linux/drivers/Makefile b/arch/um/os-Linux/drivers/Makefile
new file mode 100644
index 0000000..6c546dc
--- /dev/null
+++ b/arch/um/os-Linux/drivers/Makefile
@@ -0,0 +1,13 @@
+# 
+# Copyright (C) 2000, 2002 Jeff Dike (jdike@karaya.com)
+# Licensed under the GPL
+#
+
+ethertap-objs := ethertap_kern.o ethertap_user.o
+tuntap-objs := tuntap_kern.o tuntap_user.o
+
+obj-y = 
+obj-$(CONFIG_UML_NET_ETHERTAP) += ethertap.o
+obj-$(CONFIG_UML_NET_TUNTAP) += tuntap.o
+
+include arch/um/scripts/Makefile.rules
diff --git a/arch/um/os-Linux/drivers/etap.h b/arch/um/os-Linux/drivers/etap.h
new file mode 100644
index 0000000..b84f6c4
--- /dev/null
+++ b/arch/um/os-Linux/drivers/etap.h
@@ -0,0 +1,27 @@
+/* 
+ * Copyright (C) 2001 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include "net_user.h"
+
+struct ethertap_data {
+	char *dev_name;
+	char *gate_addr;
+	int data_fd;
+	int control_fd;
+	void *dev;
+};
+
+extern struct net_user_info ethertap_user_info;
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/drivers/ethertap_kern.c b/arch/um/os-Linux/drivers/ethertap_kern.c
new file mode 100644
index 0000000..6ae4b19
--- /dev/null
+++ b/arch/um/os-Linux/drivers/ethertap_kern.c
@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and 
+ * James Leu (jleu@mindspring.net).
+ * Copyright (C) 2001 by various other people who didn't put their name here.
+ * Licensed under the GPL.
+ */
+
+#include "linux/init.h"
+#include "linux/netdevice.h"
+#include "linux/etherdevice.h"
+#include "net_kern.h"
+#include "net_user.h"
+#include "etap.h"
+
+struct ethertap_init {
+	char *dev_name;
+	char *gate_addr;
+};
+
+static void etap_init(struct net_device *dev, void *data)
+{
+	struct uml_net_private *pri;
+	struct ethertap_data *epri;
+	struct ethertap_init *init = data;
+
+	pri = dev->priv;
+	epri = (struct ethertap_data *) pri->user;
+	epri->dev_name = init->dev_name;
+	epri->gate_addr = init->gate_addr;
+	epri->data_fd = -1;
+	epri->control_fd = -1;
+	epri->dev = dev;
+
+	printk("ethertap backend - %s", epri->dev_name);
+	if (epri->gate_addr != NULL)
+		printk(", IP = %s", epri->gate_addr);
+	printk("\n");
+}
+
+static int etap_read(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+{
+	int len;
+
+	*skb = ether_adjust_skb(*skb, ETH_HEADER_ETHERTAP);
+	if(*skb == NULL) return(-ENOMEM);
+	len = net_recvfrom(fd, (*skb)->mac.raw, 
+			   (*skb)->dev->mtu + 2 * ETH_HEADER_ETHERTAP);
+	if(len <= 0) return(len);
+	skb_pull(*skb, 2);
+	len -= 2;
+	return(len);
+}
+
+static int etap_write(int fd, struct sk_buff **skb, struct uml_net_private *lp)
+{
+	if(skb_headroom(*skb) < 2){
+	  	struct sk_buff *skb2;
+
+		skb2 = skb_realloc_headroom(*skb, 2);
+		dev_kfree_skb(*skb);
+		if (skb2 == NULL) return(-ENOMEM);
+		*skb = skb2;
+	}
+	skb_push(*skb, 2);
+	return(net_send(fd, (*skb)->data, (*skb)->len));
+}
+
+struct net_kern_info ethertap_kern_info = {
+	.init			= etap_init,
+	.protocol		= eth_protocol,
+	.read			= etap_read,
+	.write 			= etap_write,
+};
+
+int ethertap_setup(char *str, char **mac_out, void *data)
+{
+	struct ethertap_init *init = data;
+
+	*init = ((struct ethertap_init)
+		{ .dev_name 	= NULL,
+		  .gate_addr 	= NULL });
+	if(tap_setup_common(str, "ethertap", &init->dev_name, mac_out,
+			    &init->gate_addr))
+		return(0);
+	if(init->dev_name == NULL){
+		printk("ethertap_setup : Missing tap device name\n");
+		return(0);
+	}
+
+	return(1);
+}
+
+static struct transport ethertap_transport = {
+	.list 		= LIST_HEAD_INIT(ethertap_transport.list),
+	.name 		= "ethertap",
+	.setup  	= ethertap_setup,
+	.user 		= &ethertap_user_info,
+	.kern 		= &ethertap_kern_info,
+	.private_size 	= sizeof(struct ethertap_data),
+};
+
+static int register_ethertap(void)
+{
+	register_transport(&ethertap_transport);
+	return(1);
+}
+
+__initcall(register_ethertap);
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/drivers/ethertap_user.c b/arch/um/os-Linux/drivers/ethertap_user.c
new file mode 100644
index 0000000..cd4d654
--- /dev/null
+++ b/arch/um/os-Linux/drivers/ethertap_user.c
@@ -0,0 +1,240 @@
+/*
+ * Copyright (C) 2001 Lennert Buytenhek (buytenh@gnu.org) and 
+ * James Leu (jleu@mindspring.net).
+ * Copyright (C) 2001 by various other people who didn't put their name here.
+ * Licensed under the GPL.
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <sys/errno.h>
+#include <sys/socket.h>
+#include <sys/wait.h>
+#include <sys/un.h>
+#include <net/if.h>
+#include "user.h"
+#include "kern_util.h"
+#include "user_util.h"
+#include "net_user.h"
+#include "etap.h"
+#include "helper.h"
+#include "os.h"
+
+#define MAX_PACKET ETH_MAX_PACKET
+
+void etap_user_init(void *data, void *dev)
+{
+	struct ethertap_data *pri = data;
+
+	pri->dev = dev;
+}
+
+struct addr_change {
+	enum { ADD_ADDR, DEL_ADDR } what;
+	unsigned char addr[4];
+	unsigned char netmask[4];
+};
+
+static void etap_change(int op, unsigned char *addr, unsigned char *netmask,
+			int fd)
+{
+	struct addr_change change;
+	void *output;
+	int n;
+
+	change.what = op;
+	memcpy(change.addr, addr, sizeof(change.addr));
+	memcpy(change.netmask, netmask, sizeof(change.netmask));
+	n = os_write_file(fd, &change, sizeof(change));
+	if(n != sizeof(change))
+		printk("etap_change - request failed, err = %d\n", -n);
+	output = um_kmalloc(page_size());
+	if(output == NULL)
+		printk("etap_change : Failed to allocate output buffer\n");
+	read_output(fd, output, page_size());
+	if(output != NULL){
+		printk("%s", output);
+		kfree(output);
+	}
+}
+
+static void etap_open_addr(unsigned char *addr, unsigned char *netmask,
+			   void *arg)
+{
+	etap_change(ADD_ADDR, addr, netmask, *((int *) arg));
+}
+
+static void etap_close_addr(unsigned char *addr, unsigned char *netmask,
+			    void *arg)
+{
+	etap_change(DEL_ADDR, addr, netmask, *((int *) arg));
+}
+
+struct etap_pre_exec_data {
+	int control_remote;
+	int control_me;
+	int data_me;
+};
+
+static void etap_pre_exec(void *arg)
+{
+	struct etap_pre_exec_data *data = arg;
+
+	dup2(data->control_remote, 1);
+	os_close_file(data->data_me);
+	os_close_file(data->control_me);
+}
+
+static int etap_tramp(char *dev, char *gate, int control_me, 
+		      int control_remote, int data_me, int data_remote)
+{
+	struct etap_pre_exec_data pe_data;
+	int pid, status, err, n;
+	char version_buf[sizeof("nnnnn\0")];
+	char data_fd_buf[sizeof("nnnnnn\0")];
+	char gate_buf[sizeof("nnn.nnn.nnn.nnn\0")];
+	char *setup_args[] = { "uml_net", version_buf, "ethertap", dev,
+			       data_fd_buf, gate_buf, NULL };
+	char *nosetup_args[] = { "uml_net", version_buf, "ethertap", 
+				 dev, data_fd_buf, NULL };
+	char **args, c;
+
+	sprintf(data_fd_buf, "%d", data_remote);
+	sprintf(version_buf, "%d", UML_NET_VERSION);
+	if(gate != NULL){
+		strcpy(gate_buf, gate);
+		args = setup_args;
+	}
+	else args = nosetup_args;
+
+	err = 0;
+	pe_data.control_remote = control_remote;
+	pe_data.control_me = control_me;
+	pe_data.data_me = data_me;
+	pid = run_helper(etap_pre_exec, &pe_data, args, NULL);
+
+	if(pid < 0) err = pid;
+	os_close_file(data_remote);
+	os_close_file(control_remote);
+	n = os_read_file(control_me, &c, sizeof(c));
+	if(n != sizeof(c)){
+		printk("etap_tramp : read of status failed, err = %d\n", -n);
+		return(-EINVAL);
+	}
+	if(c != 1){
+		printk("etap_tramp : uml_net failed\n");
+		err = -EINVAL;
+		CATCH_EINTR(n = waitpid(pid, &status, 0));
+		if(n < 0)
+			err = -errno;
+		else if(!WIFEXITED(status) || (WEXITSTATUS(status) != 1))
+			printk("uml_net didn't exit with status 1\n");
+	}
+	return(err);
+}
+
+static int etap_open(void *data)
+{
+	struct ethertap_data *pri = data;
+	char *output;
+	int data_fds[2], control_fds[2], err, output_len;
+
+	err = tap_open_common(pri->dev, pri->gate_addr);
+	if(err) return(err);
+
+	err = os_pipe(data_fds, 0, 0);
+	if(err < 0){
+		printk("data os_pipe failed - err = %d\n", -err);
+		return(err);
+	}
+
+	err = os_pipe(control_fds, 1, 0);
+	if(err < 0){
+		printk("control os_pipe failed - err = %d\n", -err);
+		return(err);
+	}
+	
+	err = etap_tramp(pri->dev_name, pri->gate_addr, control_fds[0], 
+			 control_fds[1], data_fds[0], data_fds[1]);
+	output_len = page_size();
+	output = um_kmalloc(output_len);
+	read_output(control_fds[0], output, output_len);
+
+	if(output == NULL)
+		printk("etap_open : failed to allocate output buffer\n");
+	else {
+		printk("%s", output);
+		kfree(output);
+	}
+
+	if(err < 0){
+		printk("etap_tramp failed - err = %d\n", -err);
+		return(err);
+	}
+
+	pri->data_fd = data_fds[0];
+	pri->control_fd = control_fds[0];
+	iter_addresses(pri->dev, etap_open_addr, &pri->control_fd);
+	return(data_fds[0]);
+}
+
+static void etap_close(int fd, void *data)
+{
+	struct ethertap_data *pri = data;
+
+	iter_addresses(pri->dev, etap_close_addr, &pri->control_fd);
+	os_close_file(fd);
+	os_shutdown_socket(pri->data_fd, 1, 1);
+	os_close_file(pri->data_fd);
+	pri->data_fd = -1;
+	os_close_file(pri->control_fd);
+	pri->control_fd = -1;
+}
+
+static int etap_set_mtu(int mtu, void *data)
+{
+	return(mtu);
+}
+
+static void etap_add_addr(unsigned char *addr, unsigned char *netmask,
+			  void *data)
+{
+	struct ethertap_data *pri = data;
+
+	tap_check_ips(pri->gate_addr, addr);
+	if(pri->control_fd == -1) return;
+	etap_open_addr(addr, netmask, &pri->control_fd);
+}
+
+static void etap_del_addr(unsigned char *addr, unsigned char *netmask, 
+			  void *data)
+{
+	struct ethertap_data *pri = data;
+
+	if(pri->control_fd == -1) return;
+	etap_close_addr(addr, netmask, &pri->control_fd);
+}
+
+struct net_user_info ethertap_user_info = {
+	.init		= etap_user_init,
+	.open		= etap_open,
+	.close	 	= etap_close,
+	.remove	 	= NULL,
+	.set_mtu	= etap_set_mtu,
+	.add_address	= etap_add_addr,
+	.delete_address = etap_del_addr,
+	.max_packet	= MAX_PACKET - ETH_HEADER_ETHERTAP
+};
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/drivers/tuntap.h b/arch/um/os-Linux/drivers/tuntap.h
new file mode 100644
index 0000000..25d4a28
--- /dev/null
+++ b/arch/um/os-Linux/drivers/tuntap.h
@@ -0,0 +1,32 @@
+/* 
+ * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __UM_TUNTAP_H
+#define __UM_TUNTAP_H
+
+#include "net_user.h"
+
+struct tuntap_data {
+	char *dev_name;
+	int fixed_config;
+	char *gate_addr;
+	int fd;
+	void *dev;
+};
+
+extern struct net_user_info tuntap_user_info;
+
+#endif
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/drivers/tuntap_kern.c b/arch/um/os-Linux/drivers/tuntap_kern.c
new file mode 100644
index 0000000..4202b9e
--- /dev/null
+++ b/arch/um/os-Linux/drivers/tuntap_kern.c
@@ -0,0 +1,104 @@
+/* 
+ * Copyright (C) 2001 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/stddef.h"
+#include "linux/netdevice.h"
+#include "linux/etherdevice.h"
+#include "linux/skbuff.h"
+#include "linux/init.h"
+#include "asm/errno.h"
+#include "net_kern.h"
+#include "net_user.h"
+#include "tuntap.h"
+
+struct tuntap_init {
+	char *dev_name;
+	char *gate_addr;
+};
+
+static void tuntap_init(struct net_device *dev, void *data)
+{
+	struct uml_net_private *pri;
+	struct tuntap_data *tpri;
+	struct tuntap_init *init = data;
+
+	pri = dev->priv;
+	tpri = (struct tuntap_data *) pri->user;
+	tpri->dev_name = init->dev_name;
+	tpri->fixed_config = (init->dev_name != NULL);
+	tpri->gate_addr = init->gate_addr;
+	tpri->fd = -1;
+	tpri->dev = dev;
+
+	printk("TUN/TAP backend - ");
+	if (tpri->gate_addr != NULL)
+		printk("IP = %s", tpri->gate_addr);
+	printk("\n");
+}
+
+static int tuntap_read(int fd, struct sk_buff **skb, 
+		       struct uml_net_private *lp)
+{
+	*skb = ether_adjust_skb(*skb, ETH_HEADER_OTHER);
+	if(*skb == NULL) return(-ENOMEM);
+	return(net_read(fd, (*skb)->mac.raw, 
+			(*skb)->dev->mtu + ETH_HEADER_OTHER));
+}
+
+static int tuntap_write(int fd, struct sk_buff **skb, 
+			struct uml_net_private *lp)
+{
+	return(net_write(fd, (*skb)->data, (*skb)->len));
+}
+
+struct net_kern_info tuntap_kern_info = {
+	.init			= tuntap_init,
+	.protocol		= eth_protocol,
+	.read			= tuntap_read,
+	.write 			= tuntap_write,
+};
+
+int tuntap_setup(char *str, char **mac_out, void *data)
+{
+	struct tuntap_init *init = data;
+
+	*init = ((struct tuntap_init)
+		{ .dev_name 	= NULL,
+		  .gate_addr 	= NULL });
+	if(tap_setup_common(str, "tuntap", &init->dev_name, mac_out,
+			    &init->gate_addr))
+		return(0);
+
+	return(1);
+}
+
+static struct transport tuntap_transport = {
+	.list 		= LIST_HEAD_INIT(tuntap_transport.list),
+	.name 		= "tuntap",
+	.setup  	= tuntap_setup,
+	.user 		= &tuntap_user_info,
+	.kern 		= &tuntap_kern_info,
+	.private_size 	= sizeof(struct tuntap_data),
+	.setup_size 	= sizeof(struct tuntap_init),
+};
+
+static int register_tuntap(void)
+{
+	register_transport(&tuntap_transport);
+	return(1);
+}
+
+__initcall(register_tuntap);
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/drivers/tuntap_user.c b/arch/um/os-Linux/drivers/tuntap_user.c
new file mode 100644
index 0000000..4b83c6c
--- /dev/null
+++ b/arch/um/os-Linux/drivers/tuntap_user.c
@@ -0,0 +1,225 @@
+/* 
+ * Copyright (C) 2001, 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/wait.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/uio.h>
+#include <sys/ioctl.h>
+#include <net/if.h>
+#include <linux/if_tun.h>
+#include "net_user.h"
+#include "tuntap.h"
+#include "kern_util.h"
+#include "user_util.h"
+#include "user.h"
+#include "helper.h"
+#include "os.h"
+
+#define MAX_PACKET ETH_MAX_PACKET
+
+void tuntap_user_init(void *data, void *dev)
+{
+	struct tuntap_data *pri = data;
+
+	pri->dev = dev;
+}
+
+static void tuntap_add_addr(unsigned char *addr, unsigned char *netmask,
+			    void *data)
+{
+	struct tuntap_data *pri = data;
+
+	tap_check_ips(pri->gate_addr, addr);
+	if((pri->fd == -1) || pri->fixed_config) return;
+	open_addr(addr, netmask, pri->dev_name);
+}
+
+static void tuntap_del_addr(unsigned char *addr, unsigned char *netmask,
+			    void *data)
+{
+	struct tuntap_data *pri = data;
+
+	if((pri->fd == -1) || pri->fixed_config) return;
+	close_addr(addr, netmask, pri->dev_name);
+}
+
+struct tuntap_pre_exec_data {
+	int stdout;
+	int close_me;
+};
+
+static void tuntap_pre_exec(void *arg)
+{
+	struct tuntap_pre_exec_data *data = arg;
+	
+	dup2(data->stdout, 1);
+	os_close_file(data->close_me);
+}
+
+static int tuntap_open_tramp(char *gate, int *fd_out, int me, int remote,
+			     char *buffer, int buffer_len, int *used_out)
+{
+	struct tuntap_pre_exec_data data;
+	char version_buf[sizeof("nnnnn\0")];
+	char *argv[] = { "uml_net", version_buf, "tuntap", "up", gate,
+			 NULL };
+	char buf[CMSG_SPACE(sizeof(*fd_out))];
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	struct iovec iov;
+	int pid, n;
+
+	sprintf(version_buf, "%d", UML_NET_VERSION);
+
+	data.stdout = remote;
+	data.close_me = me;
+
+	pid = run_helper(tuntap_pre_exec, &data, argv, NULL);
+
+	if(pid < 0) return(-pid);
+
+	os_close_file(remote);
+
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	if(buffer != NULL){
+		iov = ((struct iovec) { buffer, buffer_len });
+		msg.msg_iov = &iov;
+		msg.msg_iovlen = 1;
+	}
+	else {
+		msg.msg_iov = NULL;
+		msg.msg_iovlen = 0;
+	}
+	msg.msg_control = buf;
+	msg.msg_controllen = sizeof(buf);
+	msg.msg_flags = 0;
+	n = recvmsg(me, &msg, 0);
+	*used_out = n;
+	if(n < 0){
+		printk("tuntap_open_tramp : recvmsg failed - errno = %d\n", 
+		       errno);
+		return(-errno);
+	}
+	CATCH_EINTR(waitpid(pid, NULL, 0));
+
+	cmsg = CMSG_FIRSTHDR(&msg);
+	if(cmsg == NULL){
+		printk("tuntap_open_tramp : didn't receive a message\n");
+		return(-EINVAL);
+	}
+	if((cmsg->cmsg_level != SOL_SOCKET) || 
+	   (cmsg->cmsg_type != SCM_RIGHTS)){
+		printk("tuntap_open_tramp : didn't receive a descriptor\n");
+		return(-EINVAL);
+	}
+	*fd_out = ((int *) CMSG_DATA(cmsg))[0];
+	return(0);
+}
+
+static int tuntap_open(void *data)
+{
+	struct ifreq ifr;
+	struct tuntap_data *pri = data;
+	char *output, *buffer;
+	int err, fds[2], len, used;
+
+	err = tap_open_common(pri->dev, pri->gate_addr);
+	if(err < 0)
+		return(err);
+
+	if(pri->fixed_config){
+		pri->fd = os_open_file("/dev/net/tun", of_rdwr(OPENFLAGS()), 0);
+		if(pri->fd < 0){
+			printk("Failed to open /dev/net/tun, err = %d\n",
+			       -pri->fd);
+			return(pri->fd);
+		}
+		memset(&ifr, 0, sizeof(ifr));
+		ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+		strlcpy(ifr.ifr_name, pri->dev_name, sizeof(ifr.ifr_name));
+		if(ioctl(pri->fd, TUNSETIFF, (void *) &ifr) < 0){
+			printk("TUNSETIFF failed, errno = %d\n", errno);
+			os_close_file(pri->fd);
+			return(-errno);
+		}
+	}
+	else {
+		err = os_pipe(fds, 0, 0);
+		if(err < 0){
+			printk("tuntap_open : os_pipe failed - err = %d\n",
+			       -err);
+			return(err);
+		}
+
+		buffer = get_output_buffer(&len);
+		if(buffer != NULL) len--;
+		used = 0;
+
+		err = tuntap_open_tramp(pri->gate_addr, &pri->fd, fds[0],
+					fds[1], buffer, len, &used);
+
+		output = buffer;
+		if(err < 0) {
+			printk("%s", output);
+			free_output_buffer(buffer);
+			printk("tuntap_open_tramp failed - err = %d\n", -err);
+			return(err);
+		}
+
+		pri->dev_name = uml_strdup(buffer);
+		output += IFNAMSIZ;
+		printk("%s", output);
+		free_output_buffer(buffer);
+
+		os_close_file(fds[0]);
+		iter_addresses(pri->dev, open_addr, pri->dev_name);
+	}
+
+	return(pri->fd);
+}
+
+static void tuntap_close(int fd, void *data)
+{
+	struct tuntap_data *pri = data;
+
+	if(!pri->fixed_config) 
+		iter_addresses(pri->dev, close_addr, pri->dev_name);
+	os_close_file(fd);
+	pri->fd = -1;
+}
+
+static int tuntap_set_mtu(int mtu, void *data)
+{
+	return(mtu);
+}
+
+struct net_user_info tuntap_user_info = {
+	.init		= tuntap_user_init,
+	.open		= tuntap_open,
+	.close	 	= tuntap_close,
+	.remove	 	= NULL,
+	.set_mtu	= tuntap_set_mtu,
+	.add_address	= tuntap_add_addr,
+	.delete_address = tuntap_del_addr,
+	.max_packet	= MAX_PACKET
+};
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/elf_aux.c b/arch/um/os-Linux/elf_aux.c
new file mode 100644
index 0000000..9aee0b6
--- /dev/null
+++ b/arch/um/os-Linux/elf_aux.c
@@ -0,0 +1,66 @@
+/*
+ *  arch/um/kernel/elf_aux.c
+ *
+ *  Scan the Elf auxiliary vector provided by the host to extract
+ *  information about vsyscall-page, etc.
+ *
+ *  Copyright (C) 2004 Fujitsu Siemens Computers GmbH
+ *  Author: Bodo Stroesser (bodo.stroesser@fujitsu-siemens.com)
+ */
+#include <elf.h>
+#include <stddef.h>
+#include "init.h"
+#include "elf_user.h"
+
+#if ELF_CLASS == ELFCLASS32
+typedef Elf32_auxv_t elf_auxv_t;
+#else
+typedef Elf64_auxv_t elf_auxv_t;
+#endif
+
+char * elf_aux_platform;
+long elf_aux_hwcap;
+
+unsigned long vsyscall_ehdr;
+unsigned long vsyscall_end;
+
+unsigned long __kernel_vsyscall;
+
+__init void scan_elf_aux( char **envp)
+{
+	long page_size = 0;
+	elf_auxv_t * auxv;
+
+	while ( *envp++ != NULL) ;
+
+	for ( auxv = (elf_auxv_t *)envp; auxv->a_type != AT_NULL; auxv++) {
+		switch ( auxv->a_type ) {
+			case AT_SYSINFO:
+				__kernel_vsyscall = auxv->a_un.a_val;
+				break;
+			case AT_SYSINFO_EHDR:
+				vsyscall_ehdr = auxv->a_un.a_val;
+				break;
+			case AT_HWCAP:
+				elf_aux_hwcap = auxv->a_un.a_val;
+				break;
+			case AT_PLATFORM:
+				elf_aux_platform = auxv->a_un.a_ptr;
+				break;
+			case AT_PAGESZ:
+				page_size = auxv->a_un.a_val;
+				break;
+		}
+	}
+	if ( ! __kernel_vsyscall || ! vsyscall_ehdr ||
+	     ! elf_aux_hwcap || ! elf_aux_platform ||
+	     ! page_size || (vsyscall_ehdr % page_size) ) {
+		__kernel_vsyscall = 0;
+		vsyscall_ehdr = 0;
+		elf_aux_hwcap = 0;
+		elf_aux_platform = "i586";
+	}
+	else {
+		vsyscall_end = vsyscall_ehdr + page_size;
+	}
+}
diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c
new file mode 100644
index 0000000..77d4066
--- /dev/null
+++ b/arch/um/os-Linux/file.c
@@ -0,0 +1,680 @@
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <sys/ioctl.h>
+#include <sys/mount.h>
+#include <sys/uio.h>
+#include "os.h"
+#include "user.h"
+#include "kern_util.h"
+
+static void copy_stat(struct uml_stat *dst, struct stat64 *src)
+{
+	*dst = ((struct uml_stat) {
+		.ust_dev     = src->st_dev,     /* device */
+		.ust_ino     = src->st_ino,     /* inode */
+		.ust_mode    = src->st_mode,    /* protection */
+		.ust_nlink   = src->st_nlink,   /* number of hard links */
+		.ust_uid     = src->st_uid,     /* user ID of owner */
+		.ust_gid     = src->st_gid,     /* group ID of owner */
+		.ust_size    = src->st_size,    /* total size, in bytes */
+		.ust_blksize = src->st_blksize, /* blocksize for filesys I/O */
+		.ust_blocks  = src->st_blocks,  /* number of blocks allocated */
+		.ust_atime   = src->st_atime,   /* time of last access */
+		.ust_mtime   = src->st_mtime,   /* time of last modification */
+		.ust_ctime   = src->st_ctime,   /* time of last change */
+	});
+}
+
+int os_stat_fd(const int fd, struct uml_stat *ubuf)
+{
+	struct stat64 sbuf;
+	int err;
+
+	do {
+		err = fstat64(fd, &sbuf);
+	} while((err < 0) && (errno == EINTR)) ;
+
+	if(err < 0)
+		return(-errno);
+
+	if(ubuf != NULL)
+		copy_stat(ubuf, &sbuf);
+	return(err);
+}
+
+int os_stat_file(const char *file_name, struct uml_stat *ubuf)
+{
+	struct stat64 sbuf;
+	int err;
+
+	do {
+		err = stat64(file_name, &sbuf);
+	} while((err < 0) && (errno == EINTR)) ;
+
+	if(err < 0)
+		return(-errno);
+
+	if(ubuf != NULL)
+		copy_stat(ubuf, &sbuf);
+	return(err);
+}
+
+int os_access(const char* file, int mode)
+{
+	int amode, err;
+
+	amode=(mode&OS_ACC_R_OK ? R_OK : 0) | (mode&OS_ACC_W_OK ? W_OK : 0) |
+	      (mode&OS_ACC_X_OK ? X_OK : 0) | (mode&OS_ACC_F_OK ? F_OK : 0) ;
+
+	err = access(file, amode);
+	if(err < 0)
+		return(-errno);
+
+	return(0);
+}
+
+void os_print_error(int error, const char* str)
+{
+	errno = error < 0 ? -error : error;
+
+	perror(str);
+}
+
+/* FIXME? required only by hostaudio (because it passes ioctls verbatim) */
+int os_ioctl_generic(int fd, unsigned int cmd, unsigned long arg)
+{
+	int err;
+
+	err = ioctl(fd, cmd, arg);
+	if(err < 0)
+		return(-errno);
+
+	return(err);
+}
+
+int os_window_size(int fd, int *rows, int *cols)
+{
+	struct winsize size;
+
+	if(ioctl(fd, TIOCGWINSZ, &size) < 0)
+		return(-errno);
+
+	*rows = size.ws_row;
+	*cols = size.ws_col;
+
+	return(0);
+}
+
+int os_new_tty_pgrp(int fd, int pid)
+{
+	if(ioctl(fd, TIOCSCTTY, 0) < 0){
+		printk("TIOCSCTTY failed, errno = %d\n", errno);
+		return(-errno);
+	}
+
+	if(tcsetpgrp(fd, pid) < 0){
+		printk("tcsetpgrp failed, errno = %d\n", errno);
+		return(-errno);
+	}
+
+	return(0);
+}
+
+/* FIXME: ensure namebuf in os_get_if_name is big enough */
+int os_get_ifname(int fd, char* namebuf)
+{
+	if(ioctl(fd, SIOCGIFNAME, namebuf) < 0)
+		return(-errno);
+
+	return(0);
+}
+
+int os_set_slip(int fd)
+{
+	int disc, sencap;
+
+	disc = N_SLIP;
+	if(ioctl(fd, TIOCSETD, &disc) < 0){
+		printk("Failed to set slip line discipline - "
+		       "errno = %d\n", errno);
+		return(-errno);
+	}
+
+	sencap = 0;
+	if(ioctl(fd, SIOCSIFENCAP, &sencap) < 0){
+		printk("Failed to set slip encapsulation - "
+		       "errno = %d\n", errno);
+		return(-errno);
+	}
+
+	return(0);
+}
+
+int os_set_owner(int fd, int pid)
+{
+	if(fcntl(fd, F_SETOWN, pid) < 0){
+		int save_errno = errno;
+
+		if(fcntl(fd, F_GETOWN, 0) != pid)
+			return(-save_errno);
+	}
+
+	return(0);
+}
+
+/* FIXME? moved wholesale from sigio_user.c to get fcntls out of that file */
+int os_sigio_async(int master, int slave)
+{
+	int flags;
+
+	flags = fcntl(master, F_GETFL);
+	if(flags < 0) {
+		printk("fcntl F_GETFL failed, errno = %d\n", errno);
+		return(-errno);
+	}
+
+	if((fcntl(master, F_SETFL, flags | O_NONBLOCK | O_ASYNC) < 0) ||
+	   (fcntl(master, F_SETOWN, os_getpid()) < 0)){
+		printk("fcntl F_SETFL or F_SETOWN failed, errno = %d\n",
+		       errno);
+		return(-errno);
+	}
+
+	if((fcntl(slave, F_SETFL, flags | O_NONBLOCK) < 0)){
+		printk("fcntl F_SETFL failed, errno = %d\n", errno);
+		return(-errno);
+	}
+
+	return(0);
+}
+
+int os_mode_fd(int fd, int mode)
+{
+	int err;
+
+	do {
+		err = fchmod(fd, mode);
+	} while((err < 0) && (errno==EINTR)) ;
+
+	if(err < 0)
+		return(-errno);
+
+	return(0);
+}
+
+int os_file_type(char *file)
+{
+	struct uml_stat buf;
+	int err;
+
+	err = os_stat_file(file, &buf);
+	if(err < 0)
+		return(err);
+
+	if(S_ISDIR(buf.ust_mode)) return(OS_TYPE_DIR);
+	else if(S_ISLNK(buf.ust_mode)) return(OS_TYPE_SYMLINK);
+	else if(S_ISCHR(buf.ust_mode)) return(OS_TYPE_CHARDEV);
+	else if(S_ISBLK(buf.ust_mode)) return(OS_TYPE_BLOCKDEV);
+	else if(S_ISFIFO(buf.ust_mode)) return(OS_TYPE_FIFO);
+	else if(S_ISSOCK(buf.ust_mode)) return(OS_TYPE_SOCK);
+	else return(OS_TYPE_FILE);
+}
+
+int os_file_mode(char *file, struct openflags *mode_out)
+{
+	int err;
+
+	*mode_out = OPENFLAGS();
+
+	err = os_access(file, OS_ACC_W_OK);
+	if((err < 0) && (err != -EACCES))
+		return(err);
+
+	*mode_out = of_write(*mode_out);
+
+	err = os_access(file, OS_ACC_R_OK);
+	if((err < 0) && (err != -EACCES))
+		return(err);
+
+	*mode_out = of_read(*mode_out);
+
+	return(0);
+}
+
+int os_open_file(char *file, struct openflags flags, int mode)
+{
+	int fd, f = 0;
+
+	if(flags.r && flags.w) f = O_RDWR;
+	else if(flags.r) f = O_RDONLY;
+	else if(flags.w) f = O_WRONLY;
+	else f = 0;
+
+	if(flags.s) f |= O_SYNC;
+	if(flags.c) f |= O_CREAT;
+	if(flags.t) f |= O_TRUNC;
+	if(flags.e) f |= O_EXCL;
+
+	fd = open64(file, f, mode);
+	if(fd < 0)
+		return(-errno);
+
+	if(flags.cl && fcntl(fd, F_SETFD, 1)){
+		os_close_file(fd);
+		return(-errno);
+	}
+
+	return(fd);
+}
+
+int os_connect_socket(char *name)
+{
+	struct sockaddr_un sock;
+	int fd, err;
+
+	sock.sun_family = AF_UNIX;
+	snprintf(sock.sun_path, sizeof(sock.sun_path), "%s", name);
+
+	fd = socket(AF_UNIX, SOCK_STREAM, 0);
+	if(fd < 0)
+		return(fd);
+
+	err = connect(fd, (struct sockaddr *) &sock, sizeof(sock));
+	if(err)
+		return(-errno);
+
+	return(fd);
+}
+
+void os_close_file(int fd)
+{
+	close(fd);
+}
+
+int os_seek_file(int fd, __u64 offset)
+{
+	__u64 actual;
+
+	actual = lseek64(fd, offset, SEEK_SET);
+	if(actual != offset)
+		return(-errno);
+	return(0);
+}
+
+static int fault_buffer(void *start, int len,
+			int (*copy_proc)(void *addr, void *buf, int len))
+{
+	int page = getpagesize(), i;
+	char c;
+
+	for(i = 0; i < len; i += page){
+		if((*copy_proc)(start + i, &c, sizeof(c)))
+			return(-EFAULT);
+	}
+	if((len % page) != 0){
+		if((*copy_proc)(start + len - 1, &c, sizeof(c)))
+			return(-EFAULT);
+	}
+	return(0);
+}
+
+static int file_io(int fd, void *buf, int len,
+		   int (*io_proc)(int fd, void *buf, int len),
+		   int (*copy_user_proc)(void *addr, void *buf, int len))
+{
+	int n, err;
+
+	do {
+		n = (*io_proc)(fd, buf, len);
+		if((n < 0) && (errno == EFAULT)){
+			err = fault_buffer(buf, len, copy_user_proc);
+			if(err)
+				return(err);
+			n = (*io_proc)(fd, buf, len);
+		}
+	} while((n < 0) && (errno == EINTR));
+
+	if(n < 0)
+		return(-errno);
+	return(n);
+}
+
+int os_read_file(int fd, void *buf, int len)
+{
+	return(file_io(fd, buf, len, (int (*)(int, void *, int)) read,
+		       copy_from_user_proc));
+}
+
+int os_write_file(int fd, const void *buf, int len)
+{
+	return(file_io(fd, (void *) buf, len,
+		       (int (*)(int, void *, int)) write, copy_to_user_proc));
+}
+
+int os_file_size(char *file, long long *size_out)
+{
+	struct uml_stat buf;
+	int err;
+
+	err = os_stat_file(file, &buf);
+	if(err < 0){
+		printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
+		return(err);
+	}
+
+	if(S_ISBLK(buf.ust_mode)){
+		int fd, blocks;
+
+		fd = os_open_file(file, of_read(OPENFLAGS()), 0);
+		if(fd < 0){
+			printk("Couldn't open \"%s\", errno = %d\n", file, -fd);
+			return(fd);
+		}
+		if(ioctl(fd, BLKGETSIZE, &blocks) < 0){
+			printk("Couldn't get the block size of \"%s\", "
+			       "errno = %d\n", file, errno);
+			err = -errno;
+			os_close_file(fd);
+			return(err);
+		}
+		*size_out = ((long long) blocks) * 512;
+		os_close_file(fd);
+		return(0);
+	}
+	*size_out = buf.ust_size;
+	return(0);
+}
+
+int os_file_modtime(char *file, unsigned long *modtime)
+{
+	struct uml_stat buf;
+	int err;
+
+	err = os_stat_file(file, &buf);
+	if(err < 0){
+		printk("Couldn't stat \"%s\" : err = %d\n", file, -err);
+		return(err);
+	}
+
+	*modtime = buf.ust_mtime;
+	return(0);
+}
+
+int os_get_exec_close(int fd, int* close_on_exec)
+{
+	int ret;
+
+	do {
+		ret = fcntl(fd, F_GETFD);
+	} while((ret < 0) && (errno == EINTR)) ;
+
+	if(ret < 0)
+		return(-errno);
+
+	*close_on_exec = (ret&FD_CLOEXEC) ? 1 : 0;
+	return(ret);
+}
+
+int os_set_exec_close(int fd, int close_on_exec)
+{
+	int flag, err;
+
+	if(close_on_exec) flag = FD_CLOEXEC;
+	else flag = 0;
+
+	do {
+		err = fcntl(fd, F_SETFD, flag);
+	} while((err < 0) && (errno == EINTR)) ;
+
+	if(err < 0)
+		return(-errno);
+	return(err);
+}
+
+int os_pipe(int *fds, int stream, int close_on_exec)
+{
+	int err, type = stream ? SOCK_STREAM : SOCK_DGRAM;
+
+	err = socketpair(AF_UNIX, type, 0, fds);
+	if(err < 0)
+		return(-errno);
+
+	if(!close_on_exec)
+		return(0);
+
+	err = os_set_exec_close(fds[0], 1);
+	if(err < 0)
+		goto error;
+
+	err = os_set_exec_close(fds[1], 1);
+	if(err < 0)
+		goto error;
+
+	return(0);
+
+ error:
+	printk("os_pipe : Setting FD_CLOEXEC failed, err = %d\n", -err);
+	os_close_file(fds[1]);
+	os_close_file(fds[0]);
+	return(err);
+}
+
+int os_set_fd_async(int fd, int owner)
+{
+	/* XXX This should do F_GETFL first */
+	if(fcntl(fd, F_SETFL, O_ASYNC | O_NONBLOCK) < 0){
+		printk("os_set_fd_async : failed to set O_ASYNC and "
+		       "O_NONBLOCK on fd # %d, errno = %d\n", fd, errno);
+		return(-errno);
+	}
+#ifdef notdef
+	if(fcntl(fd, F_SETFD, 1) < 0){
+		printk("os_set_fd_async : Setting FD_CLOEXEC failed, "
+		       "errno = %d\n", errno);
+	}
+#endif
+
+	if((fcntl(fd, F_SETSIG, SIGIO) < 0) ||
+	   (fcntl(fd, F_SETOWN, owner) < 0)){
+		printk("os_set_fd_async : Failed to fcntl F_SETOWN "
+		       "(or F_SETSIG) fd %d to pid %d, errno = %d\n", fd, 
+		       owner, errno);
+		return(-errno);
+	}
+
+	return(0);
+}
+
+int os_clear_fd_async(int fd)
+{
+	int flags = fcntl(fd, F_GETFL);
+
+	flags &= ~(O_ASYNC | O_NONBLOCK);
+	if(fcntl(fd, F_SETFL, flags) < 0)
+		return(-errno);
+	return(0);
+}
+
+int os_set_fd_block(int fd, int blocking)
+{
+	int flags;
+
+	flags = fcntl(fd, F_GETFL);
+
+	if(blocking) flags &= ~O_NONBLOCK;
+	else flags |= O_NONBLOCK;
+
+	if(fcntl(fd, F_SETFL, flags) < 0){
+		printk("Failed to change blocking on fd # %d, errno = %d\n",
+		       fd, errno);
+		return(-errno);
+	}
+	return(0);
+}
+
+int os_accept_connection(int fd)
+{
+	int new;
+
+	new = accept(fd, NULL, 0);
+	if(new < 0) 
+		return(-errno);
+	return(new);
+}
+
+#ifndef SHUT_RD
+#define SHUT_RD 0
+#endif
+
+#ifndef SHUT_WR
+#define SHUT_WR 1
+#endif
+
+#ifndef SHUT_RDWR
+#define SHUT_RDWR 2
+#endif
+
+int os_shutdown_socket(int fd, int r, int w)
+{
+	int what, err;
+
+	if(r && w) what = SHUT_RDWR;
+	else if(r) what = SHUT_RD;
+	else if(w) what = SHUT_WR;
+	else {
+		printk("os_shutdown_socket : neither r or w was set\n");
+		return(-EINVAL);
+	}
+	err = shutdown(fd, what);
+	if(err < 0)
+		return(-errno);
+	return(0);
+}
+
+int os_rcv_fd(int fd, int *helper_pid_out)
+{
+	int new, n;
+	char buf[CMSG_SPACE(sizeof(new))];
+	struct msghdr msg;
+	struct cmsghdr *cmsg;
+	struct iovec iov;
+
+	msg.msg_name = NULL;
+	msg.msg_namelen = 0;
+	iov = ((struct iovec) { .iov_base  = helper_pid_out,
+				.iov_len   = sizeof(*helper_pid_out) });
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_control = buf;
+	msg.msg_controllen = sizeof(buf);
+	msg.msg_flags = 0;
+
+	n = recvmsg(fd, &msg, 0);
+	if(n < 0)
+		return(-errno);
+
+	else if(n != sizeof(iov.iov_len))
+		*helper_pid_out = -1;
+
+	cmsg = CMSG_FIRSTHDR(&msg);
+	if(cmsg == NULL){
+		printk("rcv_fd didn't receive anything, error = %d\n", errno);
+		return(-1);
+	}
+	if((cmsg->cmsg_level != SOL_SOCKET) || 
+	   (cmsg->cmsg_type != SCM_RIGHTS)){
+		printk("rcv_fd didn't receive a descriptor\n");
+		return(-1);
+	}
+
+	new = ((int *) CMSG_DATA(cmsg))[0];
+	return(new);
+}
+
+int os_create_unix_socket(char *file, int len, int close_on_exec)
+{
+	struct sockaddr_un addr;
+	int sock, err;
+
+	sock = socket(PF_UNIX, SOCK_DGRAM, 0);
+	if (sock < 0){
+		printk("create_unix_socket - socket failed, errno = %d\n",
+		       errno);
+		return(-errno);
+	}
+
+	if(close_on_exec) {
+		err = os_set_exec_close(sock, 1);
+		if(err < 0)
+			printk("create_unix_socket : close_on_exec failed, "
+		       "err = %d", -err);
+	}
+
+	addr.sun_family = AF_UNIX;
+
+	/* XXX Be more careful about overflow */
+	snprintf(addr.sun_path, len, "%s", file);
+
+	err = bind(sock, (struct sockaddr *) &addr, sizeof(addr));
+	if (err < 0){
+		printk("create_listening_socket at '%s' - bind failed, "
+		       "errno = %d\n", file, errno);
+		return(-errno);
+	}
+
+	return(sock);
+}
+
+void os_flush_stdout(void)
+{
+	fflush(stdout);
+}
+
+int os_lock_file(int fd, int excl)
+{
+	int type = excl ? F_WRLCK : F_RDLCK;
+	struct flock lock = ((struct flock) { .l_type	= type,
+					      .l_whence	= SEEK_SET,
+					      .l_start	= 0,
+					      .l_len	= 0 } );
+	int err, save;
+
+	err = fcntl(fd, F_SETLK, &lock);
+	if(!err)
+		goto out;
+
+	save = -errno;
+	err = fcntl(fd, F_GETLK, &lock);
+	if(err){
+		err = -errno;
+		goto out;
+	}
+
+	printk("F_SETLK failed, file already locked by pid %d\n", lock.l_pid);
+	err = save;
+ out:
+	return(err);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/include/file.h b/arch/um/os-Linux/include/file.h
new file mode 100644
index 0000000..d82711e
--- /dev/null
+++ b/arch/um/os-Linux/include/file.h
@@ -0,0 +1,22 @@
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#ifndef __OS_FILE_H__
+#define __OS_FILE_H__
+
+#define DEV_NULL "/dev/null"
+
+#endif
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c
new file mode 100644
index 0000000..ba9ca1c
--- /dev/null
+++ b/arch/um/os-Linux/process.c
@@ -0,0 +1,171 @@
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <signal.h>
+#include <linux/unistd.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include "ptrace_user.h"
+#include "os.h"
+#include "user.h"
+#include "user_util.h"
+
+#define ARBITRARY_ADDR -1
+#define FAILURE_PID    -1
+
+#define STAT_PATH_LEN sizeof("/proc/#######/stat\0")
+#define COMM_SCANF "%*[^)])"
+
+unsigned long os_process_pc(int pid)
+{
+	char proc_stat[STAT_PATH_LEN], buf[256];
+	unsigned long pc;
+	int fd, err;
+
+	sprintf(proc_stat, "/proc/%d/stat", pid);
+	fd = os_open_file(proc_stat, of_read(OPENFLAGS()), 0);
+	if(fd < 0){
+		printk("os_process_pc - couldn't open '%s', err = %d\n",
+		       proc_stat, -fd);
+		return(ARBITRARY_ADDR);
+	}
+	err = os_read_file(fd, buf, sizeof(buf));
+	if(err < 0){
+		printk("os_process_pc - couldn't read '%s', err = %d\n",
+		       proc_stat, -err);
+		os_close_file(fd);
+		return(ARBITRARY_ADDR);
+	}
+	os_close_file(fd);
+	pc = ARBITRARY_ADDR;
+	if(sscanf(buf, "%*d " COMM_SCANF " %*c %*d %*d %*d %*d %*d %*d %*d "
+		  "%*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d "
+		  "%*d %*d %*d %*d %*d %lu", &pc) != 1){
+		printk("os_process_pc - couldn't find pc in '%s'\n", buf);
+	}
+	return(pc);
+}
+
+int os_process_parent(int pid)
+{
+	char stat[STAT_PATH_LEN];
+	char data[256];
+	int parent, n, fd;
+
+	if(pid == -1) return(-1);
+
+	snprintf(stat, sizeof(stat), "/proc/%d/stat", pid);
+	fd = os_open_file(stat, of_read(OPENFLAGS()), 0);
+	if(fd < 0){
+		printk("Couldn't open '%s', err = %d\n", stat, -fd);
+		return(FAILURE_PID);
+	}
+
+	n = os_read_file(fd, data, sizeof(data));
+	os_close_file(fd);
+
+	if(n < 0){
+		printk("Couldn't read '%s', err = %d\n", stat, -n);
+		return(FAILURE_PID);
+	}
+
+	parent = FAILURE_PID;
+	n = sscanf(data, "%*d " COMM_SCANF " %*c %d", &parent);
+	if(n != 1)
+		printk("Failed to scan '%s'\n", data);
+
+	return(parent);
+}
+
+void os_stop_process(int pid)
+{
+	kill(pid, SIGSTOP);
+}
+
+void os_kill_process(int pid, int reap_child)
+{
+	kill(pid, SIGKILL);
+	if(reap_child)
+		CATCH_EINTR(waitpid(pid, NULL, 0));
+		
+}
+
+/* Kill off a ptraced child by all means available.  kill it normally first,
+ * then PTRACE_KILL it, then PTRACE_CONT it in case it's in a run state from
+ * which it can't exit directly.
+ */
+
+void os_kill_ptraced_process(int pid, int reap_child)
+{
+	kill(pid, SIGKILL);
+	ptrace(PTRACE_KILL, pid);
+	ptrace(PTRACE_CONT, pid);
+	if(reap_child)
+		CATCH_EINTR(waitpid(pid, NULL, 0));
+}
+
+void os_usr1_process(int pid)
+{
+	kill(pid, SIGUSR1);
+}
+
+/*Don't use the glibc version, which caches the result in TLS. It misses some
+ * syscalls, and also breaks with clone(), which does not unshare the TLS.*/
+inline _syscall0(pid_t, getpid)
+
+int os_getpid(void)
+{
+	return(getpid());
+}
+
+int os_map_memory(void *virt, int fd, unsigned long long off, unsigned long len,
+		  int r, int w, int x)
+{
+	void *loc;
+	int prot;
+
+	prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 
+		(x ? PROT_EXEC : 0);
+
+	loc = mmap64((void *) virt, len, prot, MAP_SHARED | MAP_FIXED,
+		     fd, off);
+	if(loc == MAP_FAILED)
+		return(-errno);
+	return(0);
+}
+
+int os_protect_memory(void *addr, unsigned long len, int r, int w, int x)
+{
+        int prot = ((r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 
+		    (x ? PROT_EXEC : 0));
+
+        if(mprotect(addr, len, prot) < 0)
+		return(-errno);
+        return(0);
+}
+
+int os_unmap_memory(void *addr, int len)
+{
+        int err;
+
+        err = munmap(addr, len);
+	if(err < 0)
+		return(-errno);
+        return(0);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/signal.c b/arch/um/os-Linux/signal.c
new file mode 100644
index 0000000..7eac1ba
--- /dev/null
+++ b/arch/um/os-Linux/signal.c
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2004 PathScale, Inc
+ * Licensed under the GPL
+ */
+
+#include <signal.h>
+#include "time_user.h"
+#include "mode.h"
+#include "sysdep/signal.h"
+
+void sig_handler(int sig)
+{
+	struct sigcontext *sc;
+
+	ARCH_GET_SIGCONTEXT(sc, sig);
+	CHOOSE_MODE_PROC(sig_handler_common_tt, sig_handler_common_skas,
+			 sig, sc);
+}
+
+extern int timer_irq_inited;
+
+void alarm_handler(int sig)
+{
+	struct sigcontext *sc;
+
+	ARCH_GET_SIGCONTEXT(sc, sig);
+	if(!timer_irq_inited) return;
+
+	if(sig == SIGALRM)
+		switch_timers(0);
+
+	CHOOSE_MODE_PROC(sig_handler_common_tt, sig_handler_common_skas,
+			 sig, sc);
+
+	if(sig == SIGALRM)
+		switch_timers(1);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/sys-i386/Makefile b/arch/um/os-Linux/sys-i386/Makefile
new file mode 100644
index 0000000..340ef26
--- /dev/null
+++ b/arch/um/os-Linux/sys-i386/Makefile
@@ -0,0 +1,10 @@
+#
+# Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
+# Licensed under the GPL
+#
+
+obj-$(CONFIG_MODE_SKAS) = registers.o
+
+USER_OBJS := $(obj-y)
+
+include arch/um/scripts/Makefile.rules
diff --git a/arch/um/os-Linux/sys-i386/registers.c b/arch/um/os-Linux/sys-i386/registers.c
new file mode 100644
index 0000000..148645b
--- /dev/null
+++ b/arch/um/os-Linux/sys-i386/registers.c
@@ -0,0 +1,132 @@
+/*
+ * Copyright (C) 2004 PathScale, Inc
+ * Licensed under the GPL
+ */
+
+#include <errno.h>
+#include <string.h>
+#include "sysdep/ptrace_user.h"
+#include "sysdep/ptrace.h"
+#include "uml-config.h"
+#include "skas_ptregs.h"
+#include "registers.h"
+#include "user.h"
+
+/* These are set once at boot time and not changed thereafter */
+
+static unsigned long exec_regs[HOST_FRAME_SIZE];
+static unsigned long exec_fp_regs[HOST_FP_SIZE];
+static unsigned long exec_fpx_regs[HOST_XFP_SIZE];
+static int have_fpx_regs = 1;
+
+void init_thread_registers(union uml_pt_regs *to)
+{
+	memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs));
+	memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp));
+	if(have_fpx_regs)
+		memcpy(to->skas.xfp, exec_fpx_regs, sizeof(to->skas.xfp));
+}
+
+/* XXX These need to use [GS]ETFPXREGS and copy_sc_{to,from}_user_skas needs
+ * to pass in a sufficiently large buffer
+ */
+int save_fp_registers(int pid, unsigned long *fp_regs)
+{
+	if(ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0)
+		return(-errno);
+	return(0);
+}
+
+int restore_fp_registers(int pid, unsigned long *fp_regs)
+{
+	if(ptrace(PTRACE_SETFPREGS, pid, 0, fp_regs) < 0)
+		return(-errno);
+	return(0);
+}
+
+static int move_registers(int pid, int int_op, union uml_pt_regs *regs,
+			  int fp_op, unsigned long *fp_regs)
+{
+	if(ptrace(int_op, pid, 0, regs->skas.regs) < 0)
+		return(-errno);
+
+	if(ptrace(fp_op, pid, 0, fp_regs) < 0)
+		return(-errno);
+
+	return(0);
+}
+
+void save_registers(int pid, union uml_pt_regs *regs)
+{
+	unsigned long *fp_regs;
+	int err, fp_op;
+
+	if(have_fpx_regs){
+		fp_op = PTRACE_GETFPXREGS;
+		fp_regs = regs->skas.xfp;
+	}
+	else {
+		fp_op = PTRACE_GETFPREGS;
+		fp_regs = regs->skas.fp;
+	}
+
+	err = move_registers(pid, PTRACE_GETREGS, regs, fp_op, fp_regs);
+	if(err)
+		panic("save_registers - saving registers failed, errno = %d\n",
+		      -err);
+}
+
+void restore_registers(int pid, union uml_pt_regs *regs)
+{
+	unsigned long *fp_regs;
+	int err, fp_op;
+
+	if(have_fpx_regs){
+		fp_op = PTRACE_SETFPXREGS;
+		fp_regs = regs->skas.xfp;
+	}
+	else {
+		fp_op = PTRACE_SETFPREGS;
+		fp_regs = regs->skas.fp;
+	}
+
+	err = move_registers(pid, PTRACE_SETREGS, regs, fp_op, fp_regs);
+	if(err)
+		panic("restore_registers - saving registers failed, "
+		      "errno = %d\n", -err);
+}
+
+void init_registers(int pid)
+{
+	int err;
+
+	err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
+	if(err)
+		panic("check_ptrace : PTRACE_GETREGS failed, errno = %d",
+		      err);
+
+	err = ptrace(PTRACE_GETFPXREGS, pid, 0, exec_fpx_regs);
+	if(!err)
+		return;
+
+	have_fpx_regs = 0;
+	if(err != EIO)
+		panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d",
+		      err);
+
+	err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs);
+	if(err)
+		panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d",
+		      err);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/sys-x86_64/Makefile b/arch/um/os-Linux/sys-x86_64/Makefile
new file mode 100644
index 0000000..340ef26
--- /dev/null
+++ b/arch/um/os-Linux/sys-x86_64/Makefile
@@ -0,0 +1,10 @@
+#
+# Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
+# Licensed under the GPL
+#
+
+obj-$(CONFIG_MODE_SKAS) = registers.o
+
+USER_OBJS := $(obj-y)
+
+include arch/um/scripts/Makefile.rules
diff --git a/arch/um/os-Linux/sys-x86_64/registers.c b/arch/um/os-Linux/sys-x86_64/registers.c
new file mode 100644
index 0000000..6286c97
--- /dev/null
+++ b/arch/um/os-Linux/sys-x86_64/registers.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright (C) 2004 PathScale, Inc
+ * Licensed under the GPL
+ */
+
+#include <errno.h>
+#include <string.h>
+#include "ptrace_user.h"
+#include "uml-config.h"
+#include "skas_ptregs.h"
+#include "registers.h"
+#include "user.h"
+
+/* These are set once at boot time and not changed thereafter */
+
+static unsigned long exec_regs[HOST_FRAME_SIZE];
+static unsigned long exec_fp_regs[HOST_FP_SIZE];
+
+void init_thread_registers(union uml_pt_regs *to)
+{
+	memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs));
+	memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp));
+}
+
+static int move_registers(int pid, int int_op, int fp_op,
+			  union uml_pt_regs *regs)
+{
+	if(ptrace(int_op, pid, 0, regs->skas.regs) < 0)
+		return(-errno);
+
+	if(ptrace(fp_op, pid, 0, regs->skas.fp) < 0)
+		return(-errno);
+
+	return(0);
+}
+
+void save_registers(int pid, union uml_pt_regs *regs)
+{
+	int err;
+
+	err = move_registers(pid, PTRACE_GETREGS, PTRACE_GETFPREGS, regs);
+	if(err)
+		panic("save_registers - saving registers failed, errno = %d\n",
+		      -err);
+}
+
+void restore_registers(int pid, union uml_pt_regs *regs)
+{
+	int err;
+
+	err = move_registers(pid, PTRACE_SETREGS, PTRACE_SETFPREGS, regs);
+	if(err)
+		panic("restore_registers - saving registers failed, "
+		      "errno = %d\n", -err);
+}
+
+void init_registers(int pid)
+{
+	int err;
+
+	err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
+	if(err)
+		panic("check_ptrace : PTRACE_GETREGS failed, errno = %d",
+		      err);
+
+	err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs);
+	if(err)
+		panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d",
+		      err);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c
new file mode 100644
index 0000000..cf30a39
--- /dev/null
+++ b/arch/um/os-Linux/time.c
@@ -0,0 +1,21 @@
+#include <stdlib.h>
+#include <sys/time.h>
+
+unsigned long long os_usecs(void)
+{
+	struct timeval tv;
+
+	gettimeofday(&tv, NULL);
+	return((unsigned long long) tv.tv_sec * 1000000 + tv.tv_usec);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/tty.c b/arch/um/os-Linux/tty.c
new file mode 100644
index 0000000..4cfdd18
--- /dev/null
+++ b/arch/um/os-Linux/tty.c
@@ -0,0 +1,61 @@
+/* 
+ * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
+ * Licensed under the GPL
+ */
+
+#include <stdlib.h>
+#include <errno.h>
+#include "os.h"
+#include "user.h"
+#include "kern_util.h"
+
+struct grantpt_info {
+	int fd;
+	int res;
+	int err;
+};
+
+static void grantpt_cb(void *arg)
+{
+	struct grantpt_info *info = arg;
+
+	info->res = grantpt(info->fd);
+	info->err = errno;
+}
+
+int get_pty(void)
+{
+	struct grantpt_info info;
+	int fd;
+
+	fd = os_open_file("/dev/ptmx", of_rdwr(OPENFLAGS()), 0);
+	if(fd < 0){
+		printk("get_pty : Couldn't open /dev/ptmx - err = %d\n", -fd);
+		return(fd);
+	}
+
+	info.fd = fd;
+	initial_thread_cb(grantpt_cb, &info);
+
+	if(info.res < 0){
+		printk("get_pty : Couldn't grant pty - errno = %d\n", 
+		       -info.err);
+		return(-1);
+	}
+	if(unlockpt(fd) < 0){
+		printk("get_pty : Couldn't unlock pty - errno = %d\n", errno);
+		return(-1);
+	}
+	return(fd);
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/user_syms.c b/arch/um/os-Linux/user_syms.c
new file mode 100644
index 0000000..75d7af9
--- /dev/null
+++ b/arch/um/os-Linux/user_syms.c
@@ -0,0 +1,95 @@
+#include "linux/types.h"
+#include "linux/module.h"
+
+/* Some of this are builtin function (some are not but could in the future),
+ * so I *must* declare good prototypes for them and then EXPORT them.
+ * The kernel code uses the macro defined by include/linux/string.h,
+ * so I undef macros; the userspace code does not include that and I
+ * add an EXPORT for the glibc one.*/
+
+#undef strlen
+#undef strstr
+#undef memcpy
+#undef memset
+
+extern size_t strlen(const char *);
+extern void *memcpy(void *, const void *, size_t);
+extern void *memmove(void *, const void *, size_t);
+extern void *memset(void *, int, size_t);
+extern int printf(const char *, ...);
+
+EXPORT_SYMBOL(strlen);
+EXPORT_SYMBOL(memcpy);
+EXPORT_SYMBOL(memmove);
+EXPORT_SYMBOL(memset);
+EXPORT_SYMBOL(printf);
+
+EXPORT_SYMBOL(strstr);
+
+/* Here, instead, I can provide a fake prototype. Yes, someone cares: genksyms.
+ * However, the modules will use the CRC defined *here*, no matter if it is
+ * good; so the versions of these symbols will always match
+ */
+#define EXPORT_SYMBOL_PROTO(sym)       \
+       int sym(void);                  \
+       EXPORT_SYMBOL(sym);
+
+#ifdef SUBARCH_i386
+EXPORT_SYMBOL(vsyscall_ehdr);
+EXPORT_SYMBOL(vsyscall_end);
+#endif
+
+EXPORT_SYMBOL_PROTO(__errno_location);
+
+EXPORT_SYMBOL_PROTO(access);
+EXPORT_SYMBOL_PROTO(open);
+EXPORT_SYMBOL_PROTO(open64);
+EXPORT_SYMBOL_PROTO(close);
+EXPORT_SYMBOL_PROTO(read);
+EXPORT_SYMBOL_PROTO(write);
+EXPORT_SYMBOL_PROTO(dup2);
+EXPORT_SYMBOL_PROTO(__xstat);
+EXPORT_SYMBOL_PROTO(__lxstat);
+EXPORT_SYMBOL_PROTO(__lxstat64);
+EXPORT_SYMBOL_PROTO(lseek);
+EXPORT_SYMBOL_PROTO(lseek64);
+EXPORT_SYMBOL_PROTO(chown);
+EXPORT_SYMBOL_PROTO(truncate);
+EXPORT_SYMBOL_PROTO(utime);
+EXPORT_SYMBOL_PROTO(chmod);
+EXPORT_SYMBOL_PROTO(rename);
+EXPORT_SYMBOL_PROTO(__xmknod);
+
+EXPORT_SYMBOL_PROTO(symlink);
+EXPORT_SYMBOL_PROTO(link);
+EXPORT_SYMBOL_PROTO(unlink);
+EXPORT_SYMBOL_PROTO(readlink);
+
+EXPORT_SYMBOL_PROTO(mkdir);
+EXPORT_SYMBOL_PROTO(rmdir);
+EXPORT_SYMBOL_PROTO(opendir);
+EXPORT_SYMBOL_PROTO(readdir);
+EXPORT_SYMBOL_PROTO(closedir);
+EXPORT_SYMBOL_PROTO(seekdir);
+EXPORT_SYMBOL_PROTO(telldir);
+
+EXPORT_SYMBOL_PROTO(ioctl);
+
+EXPORT_SYMBOL_PROTO(pread64);
+EXPORT_SYMBOL_PROTO(pwrite64);
+
+EXPORT_SYMBOL_PROTO(statfs);
+EXPORT_SYMBOL_PROTO(statfs64);
+
+EXPORT_SYMBOL_PROTO(getuid);
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */
diff --git a/arch/um/os-Linux/util/Makefile b/arch/um/os-Linux/util/Makefile
new file mode 100644
index 0000000..fb00ddf
--- /dev/null
+++ b/arch/um/os-Linux/util/Makefile
@@ -0,0 +1,4 @@
+hostprogs-y		:= mk_user_constants
+always			:= $(hostprogs-y)
+
+mk_user_constants-objs	:= mk_user_constants.o
diff --git a/arch/um/os-Linux/util/mk_user_constants.c b/arch/um/os-Linux/util/mk_user_constants.c
new file mode 100644
index 0000000..0933518
--- /dev/null
+++ b/arch/um/os-Linux/util/mk_user_constants.c
@@ -0,0 +1,29 @@
+#include <stdio.h>
+#include <asm/types.h>
+/* For some reason, x86_64 nowhere defines u64 and u32, even though they're
+ * used throughout the headers.
+ */
+typedef __u64 u64;
+typedef __u32 u32;
+#include <asm/user.h>
+
+int main(int argc, char **argv)
+{
+  printf("/*\n");
+  printf(" * Generated by mk_user_constants\n");
+  printf(" */\n");
+  printf("\n");
+  printf("#ifndef __UM_USER_CONSTANTS_H\n");
+  printf("#define __UM_USER_CONSTANTS_H\n");
+  printf("\n");
+  /* I'd like to use FRAME_SIZE from ptrace.h here, but that's wrong on
+   * x86_64 (216 vs 168 bytes).  user_regs_struct is the correct size on
+   * both x86_64 and i386.
+   */
+  printf("#define UM_FRAME_SIZE %d\n", (int) sizeof(struct user_regs_struct));
+
+  printf("\n");
+  printf("#endif\n");
+
+  return(0);
+}